Unify peer and route ACL filtering with multi-source peer rules

* Pin actions with SHA, replace unmaintained, add dependabot for actions

* Update FreeBSD to version 15 for tests

* Use shared actions

* Update sign-pipelines version

.github/dependabot.yml

@@ -0,0 +1,45 @@
+version: 2
+updates:
+  - package-ecosystem: "github-actions"
+    directory: "/"
+    schedule:
+      interval: "daily"
+    open-pull-requests-limit: 15
+    groups:
+      actions:
+        patterns:
+          - "*"
+    ignore:
+      # git-town/action v1.3.x crashes on cyclic PR graphs (self-loop main->main
+      # fork PRs) via its topological-sort visualization. Pinned to v1.2.1 in
+      # git-town.yml; block v1.3.x until upstream tolerates cyclic edges.
+      - dependency-name: "git-town/action"
+        update-types:
+          - "version-update:semver-minor"
+          - "version-update:semver-major"
+
+  - package-ecosystem: "gomod"
+    directories:
+      - "/"
+    schedule:
+      interval: "daily"
+    open-pull-requests-limit: 15
+    groups:
+      aws-sdk:
+        patterns:
+          - "github.com/aws/aws-sdk-go-v2/*"
+      pion:
+        patterns:
+          - "github.com/pion/*"
+      gorm:
+        patterns:
+          - "gorm.io/*"
+      otel:
+        patterns:
+          - "go.opentelemetry.io/*"
+      testcontainers:
+        patterns:
+          - "github.com/testcontainers/testcontainers-go/*"
+      wireguard:
+        patterns:
+          - "golang.zx2c4.com/wireguard*"

.github/pull_request_template.md

@@ -12,6 +12,7 @@
 - [ ] Is a feature enhancement
 - [ ] It is a refactor
 - [ ] Created tests that fail without the change (if possible)
+- [ ] This change does **not** modify the public API, gRPC protocols, functionality behavior, CLI / service flags, or introduce a new feature — **OR** I have discussed it with the NetBird team beforehand (link the issue / Slack thread in the description). See [CONTRIBUTING.md](https://github.com/netbirdio/netbird/blob/main/CONTRIBUTING.md#discuss-changes-with-the-netbird-team-first).
 
 > By submitting this pull request, you confirm that you have read and agree to the terms of the [Contributor License Agreement](https://github.com/netbirdio/netbird/blob/main/CONTRIBUTOR_LICENSE_AGREEMENT.md).
 

.github/workflows/check-license-dependencies.yml

@@ -2,16 +2,16 @@ name: Check License Dependencies
 
 on:
   push:
-    branches: [ main ]
+    branches: [main]
     paths:
-      - 'go.mod'
-      - 'go.sum'
-      - '.github/workflows/check-license-dependencies.yml'
+      - "go.mod"
+      - "go.sum"
+      - ".github/workflows/check-license-dependencies.yml"
   pull_request:
     paths:
-      - 'go.mod'
-      - 'go.sum'
-      - '.github/workflows/check-license-dependencies.yml'
+      - "go.mod"
+      - "go.sum"
+      - ".github/workflows/check-license-dependencies.yml"
 
 jobs:
   check-internal-dependencies:
@@ -19,7 +19,10 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-      - uses: actions/checkout@v4
+      - name: Checkout code
+        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        with:
+          persist-credentials: false
 
       - name: Check for problematic license dependencies
         run: |
@@ -56,55 +59,57 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-    - uses: actions/checkout@v4
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        with:
+          persist-credentials: false
 
-    - name: Set up Go
-      uses: actions/setup-go@v5
-      with:
-        go-version-file: 'go.mod'
-        cache: true
+      - name: Set up Go
+        uses: actions/setup-go@4b73464bb391d4059bd26b0524d20df3927bd417 # v6.3.0
+        with:
+          go-version-file: "go.mod"
+          cache: true
 
-    - name: Install go-licenses
-      run: go install github.com/google/go-licenses@v1.6.0
+      - name: Install go-licenses
+        run: go install github.com/google/go-licenses@v1.6.0
 
-    - name: Check for GPL/AGPL licensed dependencies
-      run: |
-        echo "Checking for GPL/AGPL/LGPL licensed dependencies..."
-        echo ""
-
-        # Check all Go packages for copyleft licenses, excluding internal netbird packages
-        COPYLEFT_DEPS=$(go-licenses report ./... 2>/dev/null | grep -E 'GPL|AGPL|LGPL' | grep -v 'github.com/netbirdio/netbird/' || true)
-
-        if [ -n "$COPYLEFT_DEPS" ]; then
-          echo "Found copyleft licensed dependencies:"
-          echo "$COPYLEFT_DEPS"
+      - name: Check for GPL/AGPL licensed dependencies
+        run: |
+          echo "Checking for GPL/AGPL/LGPL licensed dependencies..."
           echo ""
 
-          # Filter out dependencies that are only pulled in by internal AGPL packages
-          INCOMPATIBLE=""
-          while IFS=',' read -r package url license; do
-            if echo "$license" | grep -qE 'GPL-[0-9]|AGPL-[0-9]|LGPL-[0-9]'; then
-              # Find ALL packages that import this GPL package using go list
-              IMPORTERS=$(go list -json -deps ./... 2>/dev/null | jq -r "select(.Imports[]? == \"$package\") | .ImportPath")
+          # Check all Go packages for copyleft licenses, excluding internal netbird packages
+          COPYLEFT_DEPS=$(go-licenses report ./... 2>/dev/null | grep -E 'GPL|AGPL|LGPL' | grep -v 'github.com/netbirdio/netbird/' || true)
 
-              # Check if any importer is NOT in management/signal/relay
-              BSD_IMPORTER=$(echo "$IMPORTERS" | grep -v "github.com/netbirdio/netbird/\(management\|signal\|relay\|proxy\|combined\|tools/idp-migrate\)" | head -1)
-
-              if [ -n "$BSD_IMPORTER" ]; then
-                echo "❌ $package ($license) is imported by BSD-licensed code: $BSD_IMPORTER"
-                INCOMPATIBLE="${INCOMPATIBLE}${package},${url},${license}\n"
-              else
-                echo "✓ $package ($license) is only used by internal AGPL packages - OK"
-              fi
-            fi
-          done <<< "$COPYLEFT_DEPS"
-
-          if [ -n "$INCOMPATIBLE" ]; then
+          if [ -n "$COPYLEFT_DEPS" ]; then
+            echo "Found copyleft licensed dependencies:"
+            echo "$COPYLEFT_DEPS"
             echo ""
-            echo "❌ INCOMPATIBLE licenses found that are used by BSD-licensed code:"
-            echo -e "$INCOMPATIBLE"
-            exit 1
-          fi
-        fi
 
-        echo "✅ All external license dependencies are compatible with BSD-3-Clause"
+            # Filter out dependencies that are only pulled in by internal AGPL packages
+            INCOMPATIBLE=""
+            while IFS=',' read -r package url license; do
+              if echo "$license" | grep -qE 'GPL-[0-9]|AGPL-[0-9]|LGPL-[0-9]'; then
+                # Find ALL packages that import this GPL package using go list
+                IMPORTERS=$(go list -json -deps ./... 2>/dev/null | jq -r "select(.Imports[]? == \"$package\") | .ImportPath")
+
+                # Check if any importer is NOT in management/signal/relay
+                BSD_IMPORTER=$(echo "$IMPORTERS" | grep -v "github.com/netbirdio/netbird/\(management\|signal\|relay\|proxy\|combined\|tools/idp-migrate\)" | head -1)
+
+                if [ -n "$BSD_IMPORTER" ]; then
+                  echo "❌ $package ($license) is imported by BSD-licensed code: $BSD_IMPORTER"
+                  INCOMPATIBLE="${INCOMPATIBLE}${package},${url},${license}\n"
+                else
+                  echo "✓ $package ($license) is only used by internal AGPL packages - OK"
+                fi
+              fi
+            done <<< "$COPYLEFT_DEPS"
+
+            if [ -n "$INCOMPATIBLE" ]; then
+              echo ""
+              echo "❌ INCOMPATIBLE licenses found that are used by BSD-licensed code:"
+              echo -e "$INCOMPATIBLE"
+              exit 1
+            fi
+          fi
+
+          echo "✅ All external license dependencies are compatible with BSD-3-Clause"

.github/workflows/docs-ack.yml

@@ -83,7 +83,7 @@ jobs:
 
       - name: Verify docs PR exists (and is open or merged)
         if: steps.validate.outputs.mode == 'added'
-        uses: actions/github-script@v7
+        uses: actions/github-script@3a2844b7e9c422d3c10d287c895573f7108da1b3 # v9.0.0
         id: verify
         with:
           pr_number: ${{ steps.extract.outputs.pr_number }}

.github/workflows/forum.yml

@@ -8,11 +8,10 @@ jobs:
   post:
     runs-on: ubuntu-latest
     steps:
-      - uses: roots/discourse-topic-github-release-action@main
+      - uses: roots/discourse-topic-github-release-action@557d74ea05b6cc0c47f555c1d5d28a89d904005b # v1.1.0
         with:
           discourse-api-key: ${{ secrets.DISCOURSE_RELEASES_API_KEY }}
           discourse-base-url: https://forum.netbird.io
           discourse-author-username: NetBird
           discourse-category: 17
-          discourse-tags:
-            releases
+          discourse-tags: releases

.github/workflows/git-town.yml

@@ -3,7 +3,7 @@ name: Git Town
 on:
   pull_request:
     branches:
-      - '**'
+      - "**"
 
 jobs:
   git-town:
@@ -15,7 +15,9 @@ jobs:
       pull-requests: write
 
     steps:
-      - uses: actions/checkout@v4
-      - uses: git-town/action@v1.2.1
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        with:
+          persist-credentials: false
+      - uses: git-town/action@3d8b878379abb1ee393fb49865a28b4a6c2cd3b0 # v1.2.1
         with:
           skip-single-stacks: true

.github/workflows/golang-test-darwin.yml

@@ -16,16 +16,18 @@ jobs:
     runs-on: macos-latest
     steps:
       - name: Checkout code
-        uses: actions/checkout@v4
+        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        with:
+          persist-credentials: false
 
       - name: Install Go
-        uses: actions/setup-go@v5
+        uses: actions/setup-go@4b73464bb391d4059bd26b0524d20df3927bd417 # v6.3.0
         with:
           go-version-file: "go.mod"
           cache: false
 
       - name: Cache Go modules
-        uses: actions/cache@v4
+        uses: actions/cache@27d5ce7f107fe9357f9df03efb73ab90386fccae # v5.0.5
         with:
           path: ~/go/pkg/mod
           key: macos-gotest-${{ hashFiles('**/go.sum') }}
@@ -44,4 +46,3 @@ jobs:
 
       - name: Test
         run: NETBIRD_STORE_ENGINE=${{ matrix.store }} CI=true go test -tags=devcert -exec 'sudo --preserve-env=CI,NETBIRD_STORE_ENGINE' -timeout 5m -p 1 $(go list ./... | grep -v -e /management -e /signal -e /relay -e /proxy -e /combined)
-

.github/workflows/golang-test-freebsd.yml

@@ -15,20 +15,31 @@ jobs:
     name: "Client / Unit"
     runs-on: ubuntu-22.04
     steps:
-      - uses: actions/checkout@v4
+      - name: Checkout code
+        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        with:
+          persist-credentials: false
+
+      - name: Read Go version from go.mod
+        id: goversion
+        run: echo "version=$(awk '/^go / {print $2}' go.mod)" >> "$GITHUB_OUTPUT"
+
       - name: Test in FreeBSD
         id: test
-        uses: vmactions/freebsd-vm@v1
+        env:
+          GO_VERSION: ${{ steps.goversion.outputs.version }}
+        uses: vmactions/freebsd-vm@d1e65811565151536c0c894fff74f06351ed26e6 # v1.4.5
         with:
           usesh: true
           copyback: false
-          release: "14.2"
+          release: "15.0"
+          envs: "GO_VERSION"
           prepare: |
             pkg install -y curl pkgconf xorg
-            GO_TARBALL="go1.25.3.freebsd-amd64.tar.gz"
+            GO_TARBALL="go${GO_VERSION}.freebsd-amd64.tar.gz"
             GO_URL="https://go.dev/dl/$GO_TARBALL"
             curl -vLO "$GO_URL"
-            tar -C /usr/local -vxzf "$GO_TARBALL"            
+            tar -C /usr/local -vxzf "$GO_TARBALL"
 
           # -x - to print all executed commands
           # -e - to faile on first error

.github/workflows/golang-test-linux.yml

@@ -18,9 +18,11 @@ jobs:
       management: ${{ steps.filter.outputs.management }}
     steps:
       - name: Checkout code
-        uses: actions/checkout@v4
+        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        with:
+          persist-credentials: false
 
-      - uses: dorny/paths-filter@v3
+      - uses: dorny/paths-filter@fbd0ab8f3e69293af611ebaee6363fc25e6d187d # v4.0.1
         id: filter
         with:
           filters: |
@@ -28,7 +30,7 @@ jobs:
               - 'management/**'
 
       - name: Install Go
-        uses: actions/setup-go@v5
+        uses: actions/setup-go@4b73464bb391d4059bd26b0524d20df3927bd417 # v6.3.0
         with:
           go-version-file: "go.mod"
           cache: false
@@ -36,10 +38,10 @@ jobs:
       - name: Get Go environment
         run: |
           echo "cache=$(go env GOCACHE)" >> $GITHUB_ENV
-          echo "modcache=$(go env GOMODCACHE)" >> $GITHUB_ENV     
+          echo "modcache=$(go env GOMODCACHE)" >> $GITHUB_ENV
 
       - name: Cache Go modules
-        uses: actions/cache@v4
+        uses: actions/cache@27d5ce7f107fe9357f9df03efb73ab90386fccae # v5.0.5
         id: cache
         with:
           path: |
@@ -113,14 +115,16 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        arch: [ '386','amd64' ]
+        arch: ["386", "amd64"]
     runs-on: ubuntu-22.04
     steps:
       - name: Checkout code
-        uses: actions/checkout@v4
+        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        with:
+          persist-credentials: false
 
       - name: Install Go
-        uses: actions/setup-go@v5
+        uses: actions/setup-go@4b73464bb391d4059bd26b0524d20df3927bd417 # v6.3.0
         with:
           go-version-file: "go.mod"
           cache: false
@@ -128,10 +132,10 @@ jobs:
       - name: Get Go environment
         run: |
           echo "cache=$(go env GOCACHE)" >> $GITHUB_ENV
-          echo "modcache=$(go env GOMODCACHE)" >> $GITHUB_ENV     
+          echo "modcache=$(go env GOMODCACHE)" >> $GITHUB_ENV
 
       - name: Cache Go modules
-        uses: actions/cache/restore@v4
+        uses: actions/cache/restore@27d5ce7f107fe9357f9df03efb73ab90386fccae # v5.0.5
         with:
           path: |
             ${{ env.cache }}
@@ -154,18 +158,20 @@ jobs:
         run: git --no-pager diff --exit-code
 
       - name: Test
-        run: CGO_ENABLED=1 GOARCH=${{ matrix.arch }} CI=true go test -tags devcert -exec 'sudo' -timeout 10m -p 1 $(go list ./... | grep -v -e /management -e /signal -e /relay -e /proxy -e /combined)
+        run: CGO_ENABLED=1 GOARCH=${{ matrix.arch }} CI=true go test -tags "devcert integration" -exec 'sudo' -timeout 10m -p 1 $(go list ./... | grep -v -e /management -e /signal -e /relay -e /proxy -e /combined)
 
   test_client_on_docker:
     name: "Client (Docker) / Unit"
-    needs: [ build-cache ]
+    needs: [build-cache]
     runs-on: ubuntu-22.04
     steps:
       - name: Checkout code
-        uses: actions/checkout@v4
+        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        with:
+          persist-credentials: false
 
       - name: Install Go
-        uses: actions/setup-go@v5
+        uses: actions/setup-go@4b73464bb391d4059bd26b0524d20df3927bd417 # v6.3.0
         with:
           go-version-file: "go.mod"
           cache: false
@@ -177,7 +183,7 @@ jobs:
           echo "modcache_dir=$(go env GOMODCACHE)" >> $GITHUB_OUTPUT
 
       - name: Cache Go modules
-        uses: actions/cache/restore@v4
+        uses: actions/cache/restore@27d5ce7f107fe9357f9df03efb73ab90386fccae # v5.0.5
         id: cache-restore
         with:
           path: |
@@ -214,7 +220,7 @@ jobs:
             sh -c ' \
               apk update; apk add --no-cache \
                 ca-certificates iptables ip6tables dbus dbus-dev libpcap-dev build-base; \
-              go test -buildvcs=false -tags devcert -v -timeout 10m -p 1 $(go list -buildvcs=false ./... | grep -v -e /management -e /signal -e /relay -e /proxy -e /combined -e /client/ui -e /upload-server)
+              go test -buildvcs=false -tags "devcert integration" -v -timeout 10m -p 1 $(go list -buildvcs=false ./... | grep -v -e /management -e /signal -e /relay -e /proxy -e /combined -e /client/ui -e /upload-server)
             '
 
   test_relay:
@@ -231,10 +237,12 @@ jobs:
     runs-on: ubuntu-22.04
     steps:
       - name: Checkout code
-        uses: actions/checkout@v4
+        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        with:
+          persist-credentials: false
 
       - name: Install Go
-        uses: actions/setup-go@v5
+        uses: actions/setup-go@4b73464bb391d4059bd26b0524d20df3927bd417 # v6.3.0
         with:
           go-version-file: "go.mod"
           cache: false
@@ -246,10 +254,10 @@ jobs:
       - name: Get Go environment
         run: |
           echo "cache=$(go env GOCACHE)" >> $GITHUB_ENV
-          echo "modcache=$(go env GOMODCACHE)" >> $GITHUB_ENV     
+          echo "modcache=$(go env GOMODCACHE)" >> $GITHUB_ENV
 
       - name: Cache Go modules
-        uses: actions/cache/restore@v4
+        uses: actions/cache/restore@27d5ce7f107fe9357f9df03efb73ab90386fccae # v5.0.5
         with:
           path: |
             ${{ env.cache }}
@@ -277,14 +285,16 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        arch: [ '386','amd64' ]
+        arch: ["386", "amd64"]
     runs-on: ubuntu-22.04
     steps:
       - name: Checkout code
-        uses: actions/checkout@v4
+        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        with:
+          persist-credentials: false
 
       - name: Install Go
-        uses: actions/setup-go@v5
+        uses: actions/setup-go@4b73464bb391d4059bd26b0524d20df3927bd417 # v6.3.0
         with:
           go-version-file: "go.mod"
           cache: false
@@ -298,7 +308,7 @@ jobs:
           echo "modcache=$(go env GOMODCACHE)" >> $GITHUB_ENV
 
       - name: Cache Go modules
-        uses: actions/cache/restore@v4
+        uses: actions/cache/restore@27d5ce7f107fe9357f9df03efb73ab90386fccae # v5.0.5
         with:
           path: |
             ${{ env.cache }}
@@ -324,14 +334,16 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        arch: [ '386','amd64' ]
+        arch: ["386", "amd64"]
     runs-on: ubuntu-22.04
     steps:
       - name: Checkout code
-        uses: actions/checkout@v4
+        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        with:
+          persist-credentials: false
 
       - name: Install Go
-        uses: actions/setup-go@v5
+        uses: actions/setup-go@4b73464bb391d4059bd26b0524d20df3927bd417 # v6.3.0
         with:
           go-version-file: "go.mod"
           cache: false
@@ -343,10 +355,10 @@ jobs:
       - name: Get Go environment
         run: |
           echo "cache=$(go env GOCACHE)" >> $GITHUB_ENV
-          echo "modcache=$(go env GOMODCACHE)" >> $GITHUB_ENV     
+          echo "modcache=$(go env GOMODCACHE)" >> $GITHUB_ENV
 
       - name: Cache Go modules
-        uses: actions/cache/restore@v4
+        uses: actions/cache/restore@27d5ce7f107fe9357f9df03efb73ab90386fccae # v5.0.5
         with:
           path: |
             ${{ env.cache }}
@@ -370,19 +382,21 @@ jobs:
 
   test_management:
     name: "Management / Unit"
-    needs: [ build-cache ]
+    needs: [build-cache]
     strategy:
       fail-fast: false
       matrix:
-        arch: [ 'amd64' ]
-        store: [ 'sqlite', 'postgres', 'mysql' ]
+        arch: ["amd64"]
+        store: ["sqlite", "postgres", "mysql"]
     runs-on: ubuntu-22.04
     steps:
       - name: Checkout code
-        uses: actions/checkout@v4
+        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        with:
+          persist-credentials: false
 
       - name: Install Go
-        uses: actions/setup-go@v5
+        uses: actions/setup-go@4b73464bb391d4059bd26b0524d20df3927bd417 # v6.3.0
         with:
           go-version-file: "go.mod"
           cache: false
@@ -390,10 +404,10 @@ jobs:
       - name: Get Go environment
         run: |
           echo "cache=$(go env GOCACHE)" >> $GITHUB_ENV
-          echo "modcache=$(go env GOMODCACHE)" >> $GITHUB_ENV     
+          echo "modcache=$(go env GOMODCACHE)" >> $GITHUB_ENV
 
       - name: Cache Go modules
-        uses: actions/cache/restore@v4
+        uses: actions/cache/restore@27d5ce7f107fe9357f9df03efb73ab90386fccae # v5.0.5
         with:
           path: |
             ${{ env.cache }}
@@ -410,7 +424,7 @@ jobs:
 
       - name: Login to Docker hub
         if: github.event.pull_request && github.event.pull_request.head.repo && github.event.pull_request.head.repo.full_name == '' || github.repository == github.event.pull_request.head.repo.full_name || !github.head_ref
-        uses: docker/login-action@v3
+        uses: docker/login-action@650006c6eb7dba73a995cc03b0b2d7f5ca915bee # v4.2.0
         with:
           username: ${{ secrets.DOCKER_USER }}
           password: ${{ secrets.DOCKER_TOKEN }}
@@ -427,7 +441,7 @@ jobs:
         run: docker pull mlsmaycon/warmed-mysql:8
 
       - name: Test
-        run: |          
+        run: |
           CGO_ENABLED=1 GOARCH=${{ matrix.arch }} \
           NETBIRD_STORE_ENGINE=${{ matrix.store }} \
             CI=true \
@@ -437,13 +451,13 @@ jobs:
 
   benchmark:
     name: "Management / Benchmark"
-    needs: [ build-cache ]
+    needs: [build-cache]
     if: ${{ needs.build-cache.outputs.management == 'true' || github.event_name != 'pull_request' }}
     strategy:
       fail-fast: false
       matrix:
-        arch: [ 'amd64' ]
-        store: [ 'sqlite', 'postgres' ]
+        arch: ["amd64"]
+        store: ["sqlite", "postgres"]
     runs-on: ubuntu-22.04
     steps:
       - name: Create Docker network
@@ -474,10 +488,12 @@ jobs:
             prom/prometheus
 
       - name: Checkout code
-        uses: actions/checkout@v4
+        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        with:
+          persist-credentials: false
 
       - name: Install Go
-        uses: actions/setup-go@v5
+        uses: actions/setup-go@4b73464bb391d4059bd26b0524d20df3927bd417 # v6.3.0
         with:
           go-version-file: "go.mod"
           cache: false
@@ -485,10 +501,10 @@ jobs:
       - name: Get Go environment
         run: |
           echo "cache=$(go env GOCACHE)" >> $GITHUB_ENV
-          echo "modcache=$(go env GOMODCACHE)" >> $GITHUB_ENV     
+          echo "modcache=$(go env GOMODCACHE)" >> $GITHUB_ENV
 
       - name: Cache Go modules
-        uses: actions/cache/restore@v4
+        uses: actions/cache/restore@27d5ce7f107fe9357f9df03efb73ab90386fccae # v5.0.5
         with:
           path: |
             ${{ env.cache }}
@@ -505,7 +521,7 @@ jobs:
 
       - name: Login to Docker hub
         if: github.event.pull_request && github.event.pull_request.head.repo && github.event.pull_request.head.repo.full_name == '' || github.repository == github.event.pull_request.head.repo.full_name || !github.head_ref
-        uses: docker/login-action@v3
+        uses: docker/login-action@650006c6eb7dba73a995cc03b0b2d7f5ca915bee # v4.2.0
         with:
           username: ${{ secrets.DOCKER_USER }}
           password: ${{ secrets.DOCKER_TOKEN }}
@@ -529,13 +545,13 @@ jobs:
 
   api_benchmark:
     name: "Management / Benchmark (API)"
-    needs: [ build-cache ]
+    needs: [build-cache]
     if: ${{ needs.build-cache.outputs.management == 'true' || github.event_name != 'pull_request' }}
     strategy:
       fail-fast: false
       matrix:
-        arch: [ 'amd64' ]
-        store: [ 'sqlite', 'postgres' ]
+        arch: ["amd64"]
+        store: ["sqlite", "postgres"]
     runs-on: ubuntu-22.04
     steps:
       - name: Create Docker network
@@ -566,10 +582,12 @@ jobs:
             prom/prometheus
 
       - name: Checkout code
-        uses: actions/checkout@v4
+        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        with:
+          persist-credentials: false
 
       - name: Install Go
-        uses: actions/setup-go@v5
+        uses: actions/setup-go@4b73464bb391d4059bd26b0524d20df3927bd417 # v6.3.0
         with:
           go-version-file: "go.mod"
           cache: false
@@ -577,10 +595,10 @@ jobs:
       - name: Get Go environment
         run: |
           echo "cache=$(go env GOCACHE)" >> $GITHUB_ENV
-          echo "modcache=$(go env GOMODCACHE)" >> $GITHUB_ENV     
+          echo "modcache=$(go env GOMODCACHE)" >> $GITHUB_ENV
 
       - name: Cache Go modules
-        uses: actions/cache/restore@v4
+        uses: actions/cache/restore@27d5ce7f107fe9357f9df03efb73ab90386fccae # v5.0.5
         with:
           path: |
             ${{ env.cache }}
@@ -597,7 +615,7 @@ jobs:
 
       - name: Login to Docker hub
         if: github.event.pull_request && github.event.pull_request.head.repo && github.event.pull_request.head.repo.full_name == '' || github.repository == github.event.pull_request.head.repo.full_name || !github.head_ref
-        uses: docker/login-action@v3
+        uses: docker/login-action@650006c6eb7dba73a995cc03b0b2d7f5ca915bee # v4.2.0
         with:
           username: ${{ secrets.DOCKER_USER }}
           password: ${{ secrets.DOCKER_TOKEN }}
@@ -623,20 +641,22 @@ jobs:
 
   api_integration_test:
     name: "Management / Integration"
-    needs: [ build-cache ]
+    needs: [build-cache]
     if: ${{ needs.build-cache.outputs.management == 'true' || github.event_name != 'pull_request' }}
     strategy:
       fail-fast: false
       matrix:
-        arch: [ 'amd64' ]
-        store: [ 'sqlite', 'postgres']
+        arch: ["amd64"]
+        store: ["sqlite", "postgres"]
     runs-on: ubuntu-22.04
     steps:
       - name: Checkout code
-        uses: actions/checkout@v4
+        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        with:
+          persist-credentials: false
 
       - name: Install Go
-        uses: actions/setup-go@v5
+        uses: actions/setup-go@4b73464bb391d4059bd26b0524d20df3927bd417 # v6.3.0
         with:
           go-version-file: "go.mod"
           cache: false
@@ -644,10 +664,10 @@ jobs:
       - name: Get Go environment
         run: |
           echo "cache=$(go env GOCACHE)" >> $GITHUB_ENV
-          echo "modcache=$(go env GOMODCACHE)" >> $GITHUB_ENV     
+          echo "modcache=$(go env GOMODCACHE)" >> $GITHUB_ENV
 
       - name: Cache Go modules
-        uses: actions/cache/restore@v4
+        uses: actions/cache/restore@27d5ce7f107fe9357f9df03efb73ab90386fccae # v5.0.5
         with:
           path: |
             ${{ env.cache }}

.github/workflows/golang-test-windows.yml

@@ -18,10 +18,12 @@ jobs:
     runs-on: windows-latest
     steps:
       - name: Checkout code
-        uses: actions/checkout@v4
+        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        with:
+          persist-credentials: false
 
       - name: Install Go
-        uses: actions/setup-go@v5
+        uses: actions/setup-go@4b73464bb391d4059bd26b0524d20df3927bd417 # v6.3.0
         id: go
         with:
           go-version-file: "go.mod"
@@ -33,7 +35,7 @@ jobs:
           echo "modcache=$(go env GOMODCACHE)" >> $env:GITHUB_ENV
 
       - name: Cache Go modules
-        uses: actions/cache@v4
+        uses: actions/cache@27d5ce7f107fe9357f9df03efb73ab90386fccae # v5.0.5
         with:
           path: |
             ${{ env.cache }}
@@ -44,16 +46,15 @@ jobs:
             ${{ runner.os }}-go-
 
       - name: Download wintun
-        uses: carlosperate/download-file-action@v2
         id: download-wintun
+        uses: netbirdio/shared-actions/actions/win-download-and-verify@be5df6047383da2236e02243cceb857d8567c27e # v0.0.2
         with:
-          file-url: https://pkgs.netbird.io/wintun/wintun-0.14.1.zip
-          file-name: wintun.zip
-          location: ${{ env.downloadPath }}
-          sha256: '07c256185d6ee3652e09fa55c0b673e2624b565e02c4b9091c79ca7d2f24ef51'
+          url: https://pkgs.netbird.io/wintun/wintun-0.14.1.zip
+          destination: ${{ env.downloadPath }}\wintun.zip
+          sha256: 07c256185d6ee3652e09fa55c0b673e2624b565e02c4b9091c79ca7d2f24ef51
 
       - name: Decompressing wintun files
-        run: tar -zvxf "${{ steps.download-wintun.outputs.file-path }}" -C ${{ env.downloadPath }}
+        run: tar -xvf "${{ steps.download-wintun.outputs.file-path }}" -C ${{ env.downloadPath }}
 
       - run: mv ${{ env.downloadPath }}/wintun/bin/amd64/wintun.dll 'C:\Windows\System32\'
 

.github/workflows/golangci-lint.yml

@@ -15,9 +15,11 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout code
-        uses: actions/checkout@v4
+        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        with:
+          persist-credentials: false
       - name: codespell
-        uses: codespell-project/actions-codespell@v2
+        uses: codespell-project/actions-codespell@8f01853be192eb0f849a5c7d721450e7a467c579 # v2.2
         with:
           ignore_words_list: erro,clienta,hastable,iif,groupd,testin,groupe,cros,ans,deriver,te,userA,ede,additionals
           skip: go.mod,go.sum,**/proxy/web/**
@@ -38,13 +40,15 @@ jobs:
     timeout-minutes: 15
     steps:
       - name: Checkout code
-        uses: actions/checkout@v4
+        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        with:
+          persist-credentials: false
       - name: Check for duplicate constants
         if: matrix.os == 'ubuntu-latest'
         run: |
           ! awk '/const \(/,/)/{print $0}' management/server/activity/codes.go | grep -o '= [0-9]*' | sort | uniq -d | grep .
       - name: Install Go
-        uses: actions/setup-go@v5
+        uses: actions/setup-go@4b73464bb391d4059bd26b0524d20df3927bd417 # v6.3.0
         with:
           go-version-file: "go.mod"
           cache: false
@@ -52,7 +56,7 @@ jobs:
         if: matrix.os == 'ubuntu-latest'
         run: sudo apt update && sudo apt install -y -q libgtk-3-dev libayatana-appindicator3-dev libgl1-mesa-dev xorg-dev libpcap-dev
       - name: golangci-lint
-        uses: golangci/golangci-lint-action@4afd733a84b1f43292c63897423277bb7f4313a9 # v8.0.0
+        uses: golangci/golangci-lint-action@82606bf257cbaff209d206a39f5134f0cfbfd2ee #v9.2.1
         with:
           version: latest
           skip-cache: true

.github/workflows/install-script-test.yml

@@ -22,7 +22,9 @@ jobs:
     runs-on: ${{ matrix.os }}
     steps:
       - name: Checkout code
-        uses: actions/checkout@v4
+        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        with:
+          persist-credentials: false
 
       - name: run install script
         env:

.github/workflows/mobile-build-validation.yml

@@ -16,23 +16,25 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v4
+        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        with:
+          persist-credentials: false
       - name: Install Go
-        uses: actions/setup-go@v5
+        uses: actions/setup-go@4b73464bb391d4059bd26b0524d20df3927bd417 # v6.3.0
         with:
           go-version-file: "go.mod"
       - name: Setup Android SDK
-        uses: android-actions/setup-android@v3
+        uses: android-actions/setup-android@40fd30fb8d7440372e1316f5d1809ec01dcd3699 # v4.0.1
         with:
           cmdline-tools-version: 8512546
       - name: Setup Java
-        uses: actions/setup-java@v4
+        uses: actions/setup-java@be666c2fcd27ec809703dec50e508c2fdc7f6654
         with:
           java-version: "11"
           distribution: "adopt"
       - name: NDK Cache
         id: ndk-cache
-        uses: actions/cache@v4
+        uses: actions/cache@27d5ce7f107fe9357f9df03efb73ab90386fccae # v5.0.5
         with:
           path: /usr/local/lib/android/sdk/ndk
           key: ndk-cache-23.1.7779620
@@ -52,9 +54,11 @@ jobs:
     runs-on: macos-latest
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v4
+        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        with:
+          persist-credentials: false
       - name: Install Go
-        uses: actions/setup-go@v5
+        uses: actions/setup-go@4b73464bb391d4059bd26b0524d20df3927bd417 # v6.3.0
         with:
           go-version-file: "go.mod"
       - name: install gomobile

.github/workflows/pr-title-check.yml

@@ -9,7 +9,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Validate PR title prefix
-        uses: actions/github-script@v7
+        uses: actions/github-script@3a2844b7e9c422d3c10d287c895573f7108da1b3 # v9.0.0
         with:
           script: |
             const title = context.payload.pull_request.title;

.github/workflows/proto-version-check.yml

@@ -10,7 +10,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Check for proto tool version changes
-        uses: actions/github-script@v7
+        uses: actions/github-script@3a2844b7e9c422d3c10d287c895573f7108da1b3 # v9.0.0
         with:
           script: |
             const files = await github.paginate(github.rest.pulls.listFiles, {
@@ -20,34 +20,66 @@ jobs:
               per_page: 100,
             });
 
-            const pbFiles = files.filter(f => f.filename.endsWith('.pb.go'));
-            const missingPatch = pbFiles.filter(f => !f.patch).map(f => f.filename);
-            if (missingPatch.length > 0) {
-              core.setFailed(
-                `Cannot inspect patch data for:\n` +
-                missingPatch.map(f => `- ${f}`).join('\n') +
-                `\nThis can happen with very large PRs. Verify proto versions manually.`
-              );
+            const modifiedPbFiles = files.filter(
+              f => f.filename.endsWith('.pb.go') && f.status === 'modified'
+            );
+            if (modifiedPbFiles.length === 0) {
+              console.log('No modified .pb.go files to check');
               return;
             }
-            const versionPattern = /^[+-]\s*\/\/\s+protoc(?:-gen-go)?\s+v[\d.]+/;
-            const violations = [];
 
-            for (const file of pbFiles) {
-              const changed = file.patch
-                .split('\n')
-                .filter(line => versionPattern.test(line));
-              if (changed.length > 0) {
+            const versionPattern = /^\s*\/\/\s+protoc(?:-gen-go)?\s+v[\d.]+/;
+            const baseSha = context.payload.pull_request.base.sha;
+            const headSha = context.payload.pull_request.head.sha;
+
+            async function getVersionHeader(path, ref) {
+              try {
+                const res = await github.rest.repos.getContent({
+                  owner: context.repo.owner,
+                  repo: context.repo.repo,
+                  path,
+                  ref,
+                });
+                if (!res.data.content) {
+                  return { ok: false, reason: 'no inline content (file too large)' };
+                }
+                const content = Buffer.from(res.data.content, 'base64').toString('utf8');
+                const lines = content
+                  .split('\n')
+                  .slice(0, 20)
+                  .filter(line => versionPattern.test(line));
+                return { ok: true, lines };
+              } catch (e) {
+                return { ok: false, reason: e.message };
+              }
+            }
+
+            const violations = [];
+            for (const file of modifiedPbFiles) {
+              const [base, head] = await Promise.all([
+                getVersionHeader(file.filename, baseSha),
+                getVersionHeader(file.filename, headSha),
+              ]);
+              if (!base.ok || !head.ok) {
+                core.warning(
+                  `Skipping ${file.filename}: base=${base.ok ? 'ok' : base.reason}, head=${head.ok ? 'ok' : head.reason}`
+                );
+                continue;
+              }
+              if (base.lines.join('\n') !== head.lines.join('\n')) {
                 violations.push({
                   file: file.filename,
-                  lines: changed,
+                  base: base.lines,
+                  head: head.lines,
                 });
               }
             }
 
             if (violations.length > 0) {
               const details = violations.map(v =>
-                `${v.file}:\n${v.lines.map(l => '  ' + l).join('\n')}`
+                `${v.file}:\n` +
+                `  base:\n${v.base.map(l => '    ' + l).join('\n') || '    (none)'}\n` +
+                `  head:\n${v.head.map(l => '    ' + l).join('\n') || '    (none)'}`
               ).join('\n\n');
 
               core.setFailed(

.github/workflows/release.yml

@@ -9,7 +9,7 @@ on:
   pull_request:
 
 env:
-  SIGN_PIPE_VER: "v0.1.4"
+  SIGN_PIPE_VER: "v0.1.5"
   GORELEASER_VER: "v2.14.3"
   PRODUCT_NAME: "NetBird"
   COPYRIGHT: "NetBird GmbH"
@@ -24,7 +24,9 @@ jobs:
     runs-on: ubuntu-22.04
     steps:
       - name: Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        with:
+          persist-credentials: false
 
       - name: Generate FreeBSD port diff
         run: bash release_files/freebsd-port-diff.sh
@@ -51,19 +53,26 @@ jobs:
           echo "Generated files for version: $VERSION"
           cat netbird-*.diff
 
+      - name: Read Go version from go.mod
+        id: goversion
+        run: echo "version=$(awk '/^go / {print $2}' go.mod)" >> "$GITHUB_OUTPUT"
+
       - name: Test FreeBSD port
         if: steps.check_diff.outputs.diff_exists == 'true'
-        uses: vmactions/freebsd-vm@v1
+        env:
+          GO_VERSION: ${{ steps.goversion.outputs.version }}
+        uses: vmactions/freebsd-vm@d1e65811565151536c0c894fff74f06351ed26e6 # v1.4.5
         with:
           usesh: true
           copyback: false
           release: "15.0"
+          envs: "GO_VERSION"
           prepare: |
             # Install required packages
-            pkg install -y git curl portlint go
+            pkg install -y git curl portlint
 
             # Install Go for building
-            GO_TARBALL="go1.25.5.freebsd-amd64.tar.gz"
+            GO_TARBALL="go${GO_VERSION}.freebsd-amd64.tar.gz"
             GO_URL="https://go.dev/dl/$GO_TARBALL"
             curl -LO "$GO_URL"
             tar -C /usr/local -xzf "$GO_TARBALL"
@@ -93,19 +102,19 @@ jobs:
 
             # Show patched Makefile
             version=$(cat security/netbird/Makefile | grep -E '^DISTVERSION=' | awk '{print $NF}')
-            
+
             cd /usr/ports/security/netbird
             export BATCH=yes
             make package
             pkg add ./work/pkg/netbird-*.pkg
-            
+
             netbird version | grep "$version"
 
             echo "FreeBSD port test completed successfully!"
 
       - name: Upload FreeBSD port files
         if: steps.check_diff.outputs.diff_exists == 'true'
-        uses: actions/upload-artifact@v4
+        uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a #v7.0.1
         with:
           name: freebsd-port-files
           path: |
@@ -124,26 +133,25 @@ jobs:
     env:
       flags: ""
     steps:
+      - name: Checkout
+        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        with:
+          fetch-depth: 0 # It is required for GoReleaser to work properly
+          persist-credentials: false
+
       - name: Parse semver string
         id: semver_parser
-        uses: booxmedialtd/ws-action-parse-semver@v1
-        with:
-          input_string: ${{ (startsWith(github.ref, 'refs/tags/v') && github.ref) || 'refs/tags/v0.0.0' }}
-          version_extractor_regex: '\/v(.*)$'
+        uses: netbirdio/shared-actions/actions/parse-semver@be5df6047383da2236e02243cceb857d8567c27e # v0.0.2
 
       - if: ${{ !startsWith(github.ref, 'refs/tags/v') }}
         run: echo "flags=--snapshot" >> $GITHUB_ENV
-      - name: Checkout
-        uses: actions/checkout@v4
-        with:
-          fetch-depth: 0 # It is required for GoReleaser to work properly
       - name: Set up Go
-        uses: actions/setup-go@v5
+        uses: actions/setup-go@4b73464bb391d4059bd26b0524d20df3927bd417 # v6.3.0
         with:
           go-version-file: "go.mod"
           cache: false
       - name: Cache Go modules
-        uses: actions/cache@v4
+        uses: actions/cache/restore@27d5ce7f107fe9357f9df03efb73ab90386fccae # v5.0.5
         with:
           path: |
             ~/go/pkg/mod
@@ -156,18 +164,18 @@ jobs:
       - name: check git status
         run: git --no-pager diff --exit-code
       - name: Set up QEMU
-        uses: docker/setup-qemu-action@v2
+        uses: docker/setup-qemu-action@ce360397dd3f832beb865e1373c09c0e9f86d70a #v4.0.0
       - name: Set up Docker Buildx
-        uses: docker/setup-buildx-action@v2
+        uses: docker/setup-buildx-action@4d04d5d9486b7bd6fa91e7baf45bbb4f8b9deedd #v4.0.0
       - name: Login to Docker hub
         if: github.event_name != 'pull_request'
-        uses: docker/login-action@v1
+        uses: docker/login-action@650006c6eb7dba73a995cc03b0b2d7f5ca915bee # v4.2.0
         with:
           username: ${{ secrets.DOCKER_USER }}
           password: ${{ secrets.DOCKER_TOKEN }}
       - name: Log in to the GitHub container registry
         if: github.event_name != 'pull_request' || github.event.pull_request.head.repo.full_name == github.repository
-        uses: docker/login-action@v3
+        uses: docker/login-action@650006c6eb7dba73a995cc03b0b2d7f5ca915bee # v4.2.0
         with:
           registry: ghcr.io
           username: ${{ github.actor }}
@@ -191,7 +199,7 @@ jobs:
         run: goversioninfo -arm -64 -icon client/ui/assets/netbird.ico -manifest client/manifest.xml -product-name ${{ env.PRODUCT_NAME }} -copyright "${{ env.COPYRIGHT }}" -ver-major ${{ steps.semver_parser.outputs.major }} -ver-minor ${{ steps.semver_parser.outputs.minor }} -ver-patch ${{ steps.semver_parser.outputs.patch }} -ver-build 0 -file-version ${{ steps.semver_parser.outputs.fullversion }}.0 -product-version ${{ steps.semver_parser.outputs.fullversion }}.0 -o client/resources_windows_arm64.syso
       - name: Run GoReleaser
         id: goreleaser
-        uses: goreleaser/goreleaser-action@v4
+        uses: goreleaser/goreleaser-action@4c6ab561adb47e50c45ef534e2155934e91c40c1 # v7.2.0
         with:
           version: ${{ env.GORELEASER_VER }}
           args: release --clean ${{ env.flags }}
@@ -282,28 +290,28 @@ jobs:
           } >> "$GITHUB_OUTPUT"
       - name: upload non tags for debug purposes
         id: upload_release
-        uses: actions/upload-artifact@v4
+        uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a #v7.0.1
         with:
           name: release
           path: dist/
           retention-days: 7
       - name: upload linux packages
         id: upload_linux_packages
-        uses: actions/upload-artifact@v4
+        uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a #v7.0.1
         with:
           name: linux-packages
           path: dist/netbird_linux**
           retention-days: 7
       - name: upload windows packages
         id: upload_windows_packages
-        uses: actions/upload-artifact@v4
+        uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a #v7.0.1
         with:
           name: windows-packages
           path: dist/netbird_windows**
           retention-days: 7
       - name: upload macos packages
         id: upload_macos_packages
-        uses: actions/upload-artifact@v4
+        uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a #v7.0.1
         with:
           name: macos-packages
           path: dist/netbird_darwin**
@@ -314,27 +322,26 @@ jobs:
     outputs:
       release_ui_artifact_url: ${{ steps.upload_release_ui.outputs.artifact-url }}
     steps:
+      - name: Checkout
+        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        with:
+          fetch-depth: 0 # It is required for GoReleaser to work properly
+          persist-credentials: false
+
       - name: Parse semver string
         id: semver_parser
-        uses: booxmedialtd/ws-action-parse-semver@v1
-        with:
-          input_string: ${{ (startsWith(github.ref, 'refs/tags/v') && github.ref) || 'refs/tags/v0.0.0' }}
-          version_extractor_regex: '\/v(.*)$'
+        uses: netbirdio/shared-actions/actions/parse-semver@be5df6047383da2236e02243cceb857d8567c27e # v0.0.2
 
       - if: ${{ !startsWith(github.ref, 'refs/tags/v') }}
         run: echo "flags=--snapshot" >> $GITHUB_ENV
-      - name: Checkout
-        uses: actions/checkout@v4
-        with:
-          fetch-depth: 0 # It is required for GoReleaser to work properly
 
       - name: Set up Go
-        uses: actions/setup-go@v5
+        uses: actions/setup-go@4b73464bb391d4059bd26b0524d20df3927bd417 # v6.3.0
         with:
           go-version-file: "go.mod"
           cache: false
       - name: Cache Go modules
-        uses: actions/cache@v4
+        uses: actions/cache@27d5ce7f107fe9357f9df03efb73ab90386fccae # v5.0.5
         with:
           path: |
             ~/go/pkg/mod
@@ -375,7 +382,7 @@ jobs:
         run: goversioninfo -arm -64 -icon client/ui/assets/netbird.ico -manifest client/ui/manifest.xml -product-name ${{ env.PRODUCT_NAME }}-"UI" -copyright "${{ env.COPYRIGHT }}" -ver-major ${{ steps.semver_parser.outputs.major }} -ver-minor ${{ steps.semver_parser.outputs.minor }} -ver-patch ${{ steps.semver_parser.outputs.patch }} -ver-build 0 -file-version ${{ steps.semver_parser.outputs.fullversion }}.0 -product-version ${{ steps.semver_parser.outputs.fullversion }}.0 -o client/ui/resources_windows_arm64.syso
 
       - name: Run GoReleaser
-        uses: goreleaser/goreleaser-action@v4
+        uses: goreleaser/goreleaser-action@4c6ab561adb47e50c45ef534e2155934e91c40c1 # v7.2.0
         with:
           version: ${{ env.GORELEASER_VER }}
           args: release --config .goreleaser_ui.yaml --clean ${{ env.flags }}
@@ -404,7 +411,7 @@ jobs:
         run: rm -f /tmp/gpg-rpm-signing-key.asc
       - name: upload non tags for debug purposes
         id: upload_release_ui
-        uses: actions/upload-artifact@v4
+        uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a #v7.0.1
         with:
           name: release-ui
           path: dist/
@@ -418,16 +425,17 @@ jobs:
       - if: ${{ !startsWith(github.ref, 'refs/tags/v') }}
         run: echo "flags=--snapshot" >> $GITHUB_ENV
       - name: Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
         with:
           fetch-depth: 0 # It is required for GoReleaser to work properly
+          persist-credentials: false
       - name: Set up Go
-        uses: actions/setup-go@v5
+        uses: actions/setup-go@4b73464bb391d4059bd26b0524d20df3927bd417 # v6.3.0
         with:
           go-version-file: "go.mod"
           cache: false
       - name: Cache Go modules
-        uses: actions/cache@v4
+        uses: actions/cache@27d5ce7f107fe9357f9df03efb73ab90386fccae # v5.0.5
         with:
           path: |
             ~/go/pkg/mod
@@ -441,7 +449,7 @@ jobs:
         run: git --no-pager diff --exit-code
       - name: Run GoReleaser
         id: goreleaser
-        uses: goreleaser/goreleaser-action@v4
+        uses: goreleaser/goreleaser-action@4c6ab561adb47e50c45ef534e2155934e91c40c1 # v7.2.0
         with:
           version: ${{ env.GORELEASER_VER }}
           args: release --config .goreleaser_ui_darwin.yaml --clean ${{ env.flags }}
@@ -449,7 +457,7 @@ jobs:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
       - name: upload non tags for debug purposes
         id: upload_release_ui_darwin
-        uses: actions/upload-artifact@v4
+        uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a #v7.0.1
         with:
           name: release-ui-darwin
           path: dist/
@@ -474,27 +482,26 @@ jobs:
       PackageWorkdir: netbird_windows_${{ matrix.arch }}
       downloadPath: '${{ github.workspace }}\temp'
     steps:
+      - name: Checkout
+        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        with:
+          persist-credentials: false
+
       - name: Parse semver string
         id: semver_parser
-        uses: booxmedialtd/ws-action-parse-semver@v1
-        with:
-          input_string: ${{ (startsWith(github.ref, 'refs/tags/v') && github.ref) || 'refs/tags/v0.0.0' }}
-          version_extractor_regex: '\/v(.*)$'
-
-      - name: Checkout
-        uses: actions/checkout@v4
+        uses: netbirdio/shared-actions/actions/parse-semver@be5df6047383da2236e02243cceb857d8567c27e # v0.0.2
 
       - name: Add 7-Zip to PATH
         run: echo "C:\Program Files\7-Zip" | Out-File -FilePath $env:GITHUB_PATH -Encoding utf8 -Append
 
       - name: Download release artifacts
-        uses: actions/download-artifact@v4
+        uses: actions/download-artifact@70fc10c6e5e1ce46ad2ea6f2b72d43f7d47b13c3 # v8.0.1
         with:
           name: release
           path: release
 
       - name: Download UI release artifacts
-        uses: actions/download-artifact@v4
+        uses: actions/download-artifact@70fc10c6e5e1ce46ad2ea6f2b72d43f7d47b13c3 # v8.0.1
         with:
           name: release-ui
           path: release-ui
@@ -514,29 +521,27 @@ jobs:
           Get-ChildItem $workdir
 
       - name: Download wintun
-        uses: carlosperate/download-file-action@v2
         id: download-wintun
+        uses: netbirdio/shared-actions/actions/win-download-and-verify@be5df6047383da2236e02243cceb857d8567c27e # v0.0.2
         with:
-          file-url: https://pkgs.netbird.io/wintun/wintun-0.14.1.zip
-          file-name: wintun.zip
-          location: ${{ env.downloadPath }}
-          sha256: '07c256185d6ee3652e09fa55c0b673e2624b565e02c4b9091c79ca7d2f24ef51'
+          url: https://pkgs.netbird.io/wintun/wintun-0.14.1.zip
+          destination: ${{ env.downloadPath }}\wintun.zip
+          sha256: 07c256185d6ee3652e09fa55c0b673e2624b565e02c4b9091c79ca7d2f24ef51
 
       - name: Decompress wintun files
-        run: tar -zvxf "${{ steps.download-wintun.outputs.file-path }}" -C ${{ env.downloadPath }}
+        run: tar -xvf "${{ env.downloadPath }}\wintun.zip" -C ${{ env.downloadPath }}
 
       - name: Move wintun.dll into dist
         run: mv ${{ env.downloadPath }}\wintun\bin\${{ matrix.wintun_arch }}\wintun.dll ${{ github.workspace }}\dist\${{ env.PackageWorkdir }}\
 
       - name: Download Mesa3D (amd64 only)
-        uses: carlosperate/download-file-action@v2
         id: download-mesa3d
         if: matrix.arch == 'amd64'
+        uses: netbirdio/shared-actions/actions/win-download-and-verify@be5df6047383da2236e02243cceb857d8567c27e # v0.0.2
         with:
-          file-url: https://downloads.fdossena.com/Projects/Mesa3D/Builds/MesaForWindows-x64-20.1.8.7z
-          file-name: mesa3d.7z
-          location: ${{ env.downloadPath }}
-          sha256: '71c7cb64ec229a1d6b8d62fa08e1889ed2bd17c0eeede8689daf0f25cb31d6b9'
+          url: https://pkgs.netbird.io/mesa3d/MesaForWindows-x64-20.1.8.7z
+          destination: ${{ env.downloadPath }}\mesa3d.7z
+          sha256: 71c7cb64ec229a1d6b8d62fa08e1889ed2bd17c0eeede8689daf0f25cb31d6b9
 
       - name: Extract Mesa3D driver (amd64 only)
         if: matrix.arch == 'amd64'
@@ -547,35 +552,38 @@ jobs:
         run: mv ${{ env.downloadPath }}\opengl32.dll ${{ github.workspace }}\dist\${{ env.PackageWorkdir }}\
 
       - name: Download EnVar plugin for NSIS
-        uses: carlosperate/download-file-action@v2
+        uses: netbirdio/shared-actions/actions/win-download-and-verify@be5df6047383da2236e02243cceb857d8567c27e # v0.0.2
         with:
-          file-url: https://nsis.sourceforge.io/mediawiki/images/7/7f/EnVar_plugin.zip
-          file-name: envar_plugin.zip
-          location: ${{ github.workspace }}
+          url: https://pkgs.netbird.io/nsis/EnVar_plugin.zip
+          destination: ${{ github.workspace }}\envar_plugin.zip
+          sha256: e9aa92de351345ed82795251d838f1ae9041ba35af9d381a5780c7843b01f56a
 
       - name: Extract EnVar plugin
         run: 7z x -o"${{ github.workspace }}/NSIS_Plugins" "${{ github.workspace }}/envar_plugin.zip"
 
       - name: Download ShellExecAsUser plugin for NSIS (amd64 only)
-        uses: carlosperate/download-file-action@v2
         if: matrix.arch == 'amd64'
+        uses: netbirdio/shared-actions/actions/win-download-and-verify@be5df6047383da2236e02243cceb857d8567c27e # v0.0.2
         with:
-          file-url: https://nsis.sourceforge.io/mediawiki/images/6/68/ShellExecAsUser_amd64-Unicode.7z
-          file-name: ShellExecAsUser_amd64-Unicode.7z
-          location: ${{ github.workspace }}
+          url: https://pkgs.netbird.io/nsis/ShellExecAsUser_amd64-Unicode.7z
+          destination: ${{ github.workspace }}\ShellExecAsUser_amd64-Unicode.7z
+          sha256: 0a55ea25c7330a92cec028eda8afcaf1b1a7092e0dfb77c21c8f654564b4ff9d
 
       - name: Extract ShellExecAsUser plugin (amd64 only)
         if: matrix.arch == 'amd64'
         run: 7z x -o"${{ github.workspace }}/NSIS_Plugins" "${{ github.workspace }}/ShellExecAsUser_amd64-Unicode.7z"
 
       - name: Build NSIS installer
-        uses: joncloud/makensis-action@v3.3
-        with:
-          additional-plugin-paths: ${{ github.workspace }}/NSIS_Plugins/Plugins
-          script-file: client/installer.nsis
-          arguments: "/V4 /DARCH=${{ matrix.arch }}"
+        shell: pwsh
         env:
           APPVER: ${{ steps.semver_parser.outputs.major }}.${{ steps.semver_parser.outputs.minor }}.${{ steps.semver_parser.outputs.patch }}.${{ github.run_id }}
+        run: |
+          $nsisPluginDir = "C:\Program Files (x86)\NSIS\Plugins\x86-unicode"
+          $srcPlugins    = "${{ github.workspace }}\NSIS_Plugins\Plugins"
+          Get-ChildItem -Path $srcPlugins -Recurse -Filter *.dll |
+            Copy-Item -Destination $nsisPluginDir -Force
+          & "C:\Program Files (x86)\NSIS\makensis.exe" /V4 "/DARCH=${{ matrix.arch }}" client\installer.nsis
+          if ($LASTEXITCODE -ne 0) { throw "makensis failed with exit code $LASTEXITCODE" }
 
       - name: Rename NSIS installer
         run: mv netbird-installer.exe netbird_installer_test_windows_${{ matrix.arch }}.exe
@@ -592,7 +600,7 @@ jobs:
 
       - name: Upload installer artifacts
         if: always()
-        uses: actions/upload-artifact@v4
+        uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a #v7.0.1
         with:
           name: windows-installer-test-${{ matrix.arch }}
           path: |
@@ -611,7 +619,7 @@ jobs:
       pull-requests: write
     steps:
       - name: Create or update PR comment
-        uses: actions/github-script@v7
+        uses: actions/github-script@3a2844b7e9c422d3c10d287c895573f7108da1b3 # v9.0.0
         env:
           RELEASE_RESULT: ${{ needs.release.result }}
           RELEASE_UI_RESULT: ${{ needs.release_ui.result }}
@@ -703,7 +711,7 @@ jobs:
     if: startsWith(github.ref, 'refs/tags/')
     steps:
       - name: Trigger binaries sign pipelines
-        uses: benc-uk/workflow-dispatch@v1
+        uses: benc-uk/workflow-dispatch@31e2b3319479a63f0ab15bf800eff9e913504e26 # v1.3.2
         with:
           workflow: Sign bin and installer
           repo: netbirdio/sign-pipelines

.github/workflows/sync-main.yml

@@ -14,9 +14,9 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Trigger main branch sync
-        uses: benc-uk/workflow-dispatch@v1
+        uses: benc-uk/workflow-dispatch@31e2b3319479a63f0ab15bf800eff9e913504e26 # v1.3.2
         with:
           workflow: sync-main.yml
           repo: ${{ secrets.UPSTREAM_REPO }}
           token: ${{ secrets.NC_GITHUB_TOKEN }}
-          inputs: '{ "sha": "${{ github.sha }}" }'
+          inputs: '{ "sha": "${{ github.sha }}" }'

.github/workflows/sync-tag.yml

@@ -3,7 +3,7 @@ name: sync tag
 on:
   push:
     tags:
-      - 'v*'
+      - "v*"
 
 concurrency:
   group: ${{ github.workflow }}-${{ github.ref }}-${{ github.head_ref || github.actor_id }}
@@ -16,7 +16,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Trigger release tag sync
-        uses: benc-uk/workflow-dispatch@v1
+        uses: benc-uk/workflow-dispatch@31e2b3319479a63f0ab15bf800eff9e913504e26 # v1.3.2
         with:
           workflow: sync-tag.yml
           ref: main
@@ -29,7 +29,7 @@ jobs:
     if: github.event.created && !github.event.deleted && startsWith(github.ref, 'refs/tags/v') && !contains(github.ref_name, '-')
     steps:
       - name: Trigger android-client submodule bump
-        uses: benc-uk/workflow-dispatch@7a027648b88c2413826b6ddd6c76114894dc5ec4 # v1.3.1
+        uses: benc-uk/workflow-dispatch@31e2b3319479a63f0ab15bf800eff9e913504e26 # v1.3.2
         with:
           workflow: bump-netbird.yml
           ref: main
@@ -42,10 +42,10 @@ jobs:
     if: github.event.created && !github.event.deleted && startsWith(github.ref, 'refs/tags/v') && !contains(github.ref_name, '-')
     steps:
       - name: Trigger ios-client submodule bump
-        uses: benc-uk/workflow-dispatch@7a027648b88c2413826b6ddd6c76114894dc5ec4 # v1.3.1
+        uses: benc-uk/workflow-dispatch@31e2b3319479a63f0ab15bf800eff9e913504e26 # v1.3.2
         with:
           workflow: bump-netbird.yml
           ref: main
           repo: netbirdio/ios-client
           token: ${{ secrets.NC_GITHUB_TOKEN }}
-          inputs: '{ "tag": "${{ github.ref_name }}" }'
+          inputs: '{ "tag": "${{ github.ref_name }}" }'

.github/workflows/test-infrastructure-files.yml

@@ -6,10 +6,10 @@ on:
       - main
   pull_request:
     paths:
-      - 'infrastructure_files/**'
-      - '.github/workflows/test-infrastructure-files.yml'
-      - 'management/cmd/**'
-      - 'signal/cmd/**'
+      - "infrastructure_files/**"
+      - ".github/workflows/test-infrastructure-files.yml"
+      - "management/cmd/**"
+      - "signal/cmd/**"
 
 concurrency:
   group: ${{ github.workflow }}-${{ github.ref }}-${{ github.head_ref || github.actor_id }}
@@ -20,7 +20,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        store: [ 'sqlite', 'postgres', 'mysql' ]
+        store: ["sqlite", "postgres", "mysql"]
     services:
       postgres:
         image: ${{ (matrix.store == 'postgres') && 'postgres' || '' }}
@@ -68,15 +68,17 @@ jobs:
         run: sudo apt-get install -y curl
 
       - name: Checkout code
-        uses: actions/checkout@v4
+        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        with:
+          persist-credentials: false
 
       - name: Install Go
-        uses: actions/setup-go@v5
+        uses: actions/setup-go@4b73464bb391d4059bd26b0524d20df3927bd417 # v6.3.0
         with:
           go-version-file: "go.mod"
 
       - name: Cache Go modules
-        uses: actions/cache@v4
+        uses: actions/cache@27d5ce7f107fe9357f9df03efb73ab90386fccae # v5.0.5
         with:
           path: ~/go/pkg/mod
           key: ${{ runner.os }}-go-${{ hashFiles('**/go.sum') }}
@@ -139,8 +141,8 @@ jobs:
           CI_NETBIRD_IDP_MGMT_CLIENT_SECRET: testing.client.secret
           CI_NETBIRD_SIGNAL_PORT: 12345
           CI_NETBIRD_STORE_CONFIG_ENGINE: ${{ matrix.store }}
-          NETBIRD_STORE_ENGINE_POSTGRES_DSN: '${{ env.NETBIRD_STORE_ENGINE_POSTGRES_DSN }}$'
-          NETBIRD_STORE_ENGINE_MYSQL_DSN: '${{ env.NETBIRD_STORE_ENGINE_MYSQL_DSN }}$'
+          NETBIRD_STORE_ENGINE_POSTGRES_DSN: "${{ env.NETBIRD_STORE_ENGINE_POSTGRES_DSN }}$"
+          NETBIRD_STORE_ENGINE_MYSQL_DSN: "${{ env.NETBIRD_STORE_ENGINE_MYSQL_DSN }}$"
           CI_NETBIRD_MGMT_IDP_SIGNKEY_REFRESH: false
           CI_NETBIRD_TURN_EXTERNAL_IP: "1.2.3.4"
           CI_NETBIRD_MGMT_DISABLE_DEFAULT_POLICY: false
@@ -254,7 +256,9 @@ jobs:
         run: sudo apt-get install -y jq
 
       - name: Checkout code
-        uses: actions/checkout@v4
+        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        with:
+          persist-credentials: false
 
       - name: run script with Zitadel PostgreSQL
         run: NETBIRD_DOMAIN=use-ip bash -x infrastructure_files/getting-started-with-zitadel.sh

.github/workflows/update-docs.yml

@@ -3,9 +3,9 @@ name: update docs
 on:
   push:
     tags:
-      - 'v*'
+      - "v*"
     paths:
-      - 'shared/management/http/api/openapi.yml'
+      - "shared/management/http/api/openapi.yml"
 
 jobs:
   trigger_docs_api_update:
@@ -13,10 +13,10 @@ jobs:
     if: startsWith(github.ref, 'refs/tags/')
     steps:
       - name: Trigger API pages generation
-        uses: benc-uk/workflow-dispatch@v1
+        uses: benc-uk/workflow-dispatch@31e2b3319479a63f0ab15bf800eff9e913504e26 # v1.3.2
         with:
           workflow: generate api pages
           repo: netbirdio/docs
           ref: "refs/heads/main"
           token: ${{ secrets.SIGN_GITHUB_TOKEN }}
-          inputs: '{ "tag": "${{ github.ref }}" }'
+          inputs: '{ "tag": "${{ github.ref }}" }'

.github/workflows/wasm-build-validation.yml

@@ -19,15 +19,17 @@ jobs:
       GOARCH: wasm
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v4
+        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        with:
+          persist-credentials: false
       - name: Install Go
-        uses: actions/setup-go@v5
+        uses: actions/setup-go@4b73464bb391d4059bd26b0524d20df3927bd417 # v6.3.0
         with:
           go-version-file: "go.mod"
       - name: Install dependencies
         run: sudo apt update && sudo apt install -y -q libgtk-3-dev libayatana-appindicator3-dev libgl1-mesa-dev xorg-dev libpcap-dev
       - name: Install golangci-lint
-        uses: golangci/golangci-lint-action@4afd733a84b1f43292c63897423277bb7f4313a9 # v8.0.0
+        uses: golangci/golangci-lint-action@82606bf257cbaff209d206a39f5134f0cfbfd2ee #v9.2.1
         with:
           version: latest
           install-mode: binary
@@ -42,9 +44,11 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v4
+        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        with:
+          persist-credentials: false
       - name: Install Go
-        uses: actions/setup-go@v5
+        uses: actions/setup-go@4b73464bb391d4059bd26b0524d20df3927bd417 # v6.3.0
         with:
           go-version-file: "go.mod"
       - name: Build Wasm client
@@ -61,8 +65,7 @@ jobs:
 
           echo "Size: ${SIZE} bytes (${SIZE_MB} MB)"
 
-          if [ ${SIZE} -gt 59768832 ]; then
-            echo "Wasm binary size (${SIZE_MB}MB) exceeds 57MB limit!"
+          if [ ${SIZE} -gt 58720256 ]; then
+            echo "Wasm binary size (${SIZE_MB}MB) exceeds 56MB limit!"
             exit 1
           fi
-

CONTRIBUTING.md

@@ -15,6 +15,7 @@ If you haven't already, join our slack workspace [here](https://docs.netbird.io/
 - [Contributing to NetBird](#contributing-to-netbird)
     - [Contents](#contents)
     - [Code of conduct](#code-of-conduct)
+    - [Discuss changes with the NetBird team first](#discuss-changes-with-the-netbird-team-first)
     - [Directory structure](#directory-structure)
     - [Development setup](#development-setup)
         - [Requirements](#requirements)
@@ -33,6 +34,14 @@ Conduct which can be found in the file [CODE_OF_CONDUCT.md](CODE_OF_CONDUCT.md).
 By participating, you are expected to uphold this code. Please report
 unacceptable behavior to community@netbird.io.
 
+## Discuss changes with the NetBird team first
+
+Changes to the **public API**, **gRPC protocols**, **functionality behavior**, **CLI / service flags**, or **new features** should be discussed with the NetBird team before you start the work. These surfaces are part of NetBird's contract with operators, self-hosters, and downstream integrators, and changes to them have compatibility, security, and release-planning implications that benefit from an early conversation.
+
+Open an issue or reach out on [Slack](https://docs.netbird.io/slack-url) to talk through what you have in mind. We'll help shape the change, flag any constraints we know about, and confirm the direction so the PR review can focus on implementation rather than design.
+
+Typical bug fixes, internal refactors, documentation updates, and tests do not need pre-discussion — open the PR directly.
+
 ## Directory structure
 
 The NetBird project monorepo is organized to maintain most of its individual dependencies code within their directories, except for a few auxiliary or shared packages.

README.md

@@ -1,147 +1,134 @@
 
 <div align="center">
-<br/>
-  <br/>
-<p align="center">
-  <img width="234" src="docs/media/logo-full.png"/>
-</p>
-  <p>
-   <a href="https://img.shields.io/badge/license-BSD--3-blue)">
-       <img src="https://sonarcloud.io/api/project_badges/measure?project=netbirdio_netbird&metric=alert_status" />
-     </a> 
-     <a href="https://github.com/netbirdio/netbird/blob/main/LICENSE">
-       <img src="https://img.shields.io/badge/license-BSD--3-blue" />
-     </a> 
-    <br>
+  <p align="center">
+    <img width="234" src="docs/media/logo-full.png" alt="NetBird logo"/>
+  </p>
+  <p align="center">
+    <a href="https://sonarcloud.io/dashboard?id=netbirdio_netbird">
+      <img src="https://sonarcloud.io/api/project_badges/measure?project=netbirdio_netbird&metric=alert_status" alt="SonarCloud alert status"/>
+    </a>
+    <a href="https://github.com/netbirdio/netbird/blob/main/LICENSE">
+      <img src="https://img.shields.io/badge/license-BSD--3-blue" alt="BSD-3 License"/>
+    </a>
     <a href="https://docs.netbird.io/slack-url">
-        <img src="https://img.shields.io/badge/slack-@netbird-red.svg?logo=slack"/>
-     </a>
+      <img src="https://img.shields.io/badge/slack-@netbird-red.svg?logo=slack" alt="NetBird Slack"/>
+    </a>
     <a href="https://forum.netbird.io">
-        <img src="https://img.shields.io/badge/community forum-@netbird-red.svg?logo=discourse"/>
-     </a>  
-     <br>
+      <img src="https://img.shields.io/badge/community%20forum-@netbird-red.svg?logo=discourse" alt="Community forum"/>
+    </a>
     <a href="https://gurubase.io/g/netbird">
-        <img src="https://img.shields.io/badge/Gurubase-Ask%20NetBird%20Guru-006BFF"/>
-     </a>    
+      <img src="https://img.shields.io/badge/Gurubase-Ask%20NetBird%20Guru-006BFF" alt="Gurubase: Ask NetBird Guru"/>
+    </a>
   </p>
 </div>
 
-
 <p align="center">
-<strong>
-  Start using NetBird at <a href="https://netbird.io/pricing">netbird.io</a>
+  <strong>
+    Start using NetBird at <a href="https://netbird.io/pricing">netbird.io</a>
+    <br/>
+    See <a href="https://netbird.io/docs/">Documentation</a>
+    <br/>
+    Join our <a href="https://docs.netbird.io/slack-url">Slack channel</a> or our <a href="https://forum.netbird.io">Community forum</a>
+  </strong>
   <br/>
-  See <a href="https://netbird.io/docs/">Documentation</a>
   <br/>
-   Join our <a href="https://docs.netbird.io/slack-url">Slack channel</a> or our <a href="https://forum.netbird.io">Community forum</a>
-  <br/>
- 
-</strong>
-<br>
-<strong>
-  🚀 <a href="https://careers.netbird.io">We are hiring! Join us at careers.netbird.io</a>
-</strong>
-<br>
-<br>
-<a href="https://registry.terraform.io/providers/netbirdio/netbird/latest">
-    New: NetBird terraform provider
-  </a> 
+  <strong>
+    🚀 <a href="https://careers.netbird.io">We are hiring! Join us at careers.netbird.io</a>
+  </strong>
 </p>
 
-<br>
-
 **NetBird combines a configuration-free peer-to-peer private network and a centralized access control system in a single platform, making it easy to create secure private networks for your organization or home.**
 
 **Connect.** NetBird creates a WireGuard-based overlay network that automatically connects your machines over an encrypted tunnel, leaving behind the hassle of opening ports, complex firewall rules, VPN gateways, and so forth.
 
 **Secure.** NetBird enables secure remote access by applying granular access policies while allowing you to manage them intuitively from a single place. Works universally on any infrastructure.
 
-### Open Source Network Security in a Single Platform
-
 https://github.com/user-attachments/assets/10cec749-bb56-4ab3-97af-4e38850108d2
 
-### Self-Host NetBird (Video)
+### Self-host NetBird (video)
+
 [![Watch the video](https://img.youtube.com/vi/bZAgpT6nzaQ/0.jpg)](https://youtu.be/bZAgpT6nzaQ)
 
 ### Key features
 
-| Connectivity | Management | Security | Automation| Platforms |
-|----|----|----|----|----|
-| <ul><li>- \[x] Kernel WireGuard</ul></li> | <ul><li>- \[x] [Admin Web UI](https://github.com/netbirdio/dashboard)</ul></li> | <ul><li>- \[x] [SSO & MFA support](https://docs.netbird.io/how-to/installation#running-net-bird-with-sso-login)</ul></li> | <ul><li>- \[x] [Public API](https://docs.netbird.io/api)</ul></li> | <ul><li>- \[x] Linux</ul></li> |
-| <ul><li>- \[x] Peer-to-peer connections</ul></li> | <ul><li>- \[x] Auto peer discovery and configuration</ui></li> | <ul><li>- \[x] [Access control - groups & rules](https://docs.netbird.io/how-to/manage-network-access)</ui></li> | <ul><li>- \[x] [Setup keys for bulk network provisioning](https://docs.netbird.io/how-to/register-machines-using-setup-keys)</ui></li> | <ul><li>- \[x] Mac</ui></li> |
-| <ul><li>- \[x] Connection relay fallback</ui></li> | <ul><li>- \[x] [IdP integrations](https://docs.netbird.io/selfhosted/identity-providers)</ui></li> | <ul><li>- \[x] [Activity logging](https://docs.netbird.io/how-to/audit-events-logging)</ui></li> | <ul><li>- \[x] [Self-hosting quickstart script](https://docs.netbird.io/selfhosted/selfhosted-quickstart)</ui></li> | <ul><li>- \[x] Windows</ui></li> |
-| <ul><li>- \[x] [Routes to external networks](https://docs.netbird.io/how-to/routing-traffic-to-private-networks)</ui></li> | <ul><li>- \[x] [Private DNS](https://docs.netbird.io/how-to/manage-dns-in-your-network)</ui></li> | <ul><li>- \[x] [Device posture checks](https://docs.netbird.io/how-to/manage-posture-checks)</ui></li> | <ul><li>- \[x] IdP groups sync with JWT</ui></li> | <ul><li>- \[x] Android</ui></li> |
-| <ul><li>- \[x] NAT traversal with BPF</ui></li> | <ul><li>- \[x] [Multiuser support](https://docs.netbird.io/how-to/add-users-to-your-network)</ui></li> | <ul><li>- \[x] Peer-to-peer encryption</ui></li> || <ul><li>- \[x] iOS</ui></li> |
-||| <ul><li>- \[x] [Quantum-resistance with Rosenpass](https://netbird.io/knowledge-hub/the-first-quantum-resistant-mesh-vpn)</ui></li> || <ul><li>- \[x] OpenWRT</ui></li> |
-||| <ul><li>- \[x] [Periodic re-authentication](https://docs.netbird.io/how-to/enforce-periodic-user-authentication)</ui></li> || <ul><li>- \[x] [Serverless](https://docs.netbird.io/how-to/netbird-on-faas)</ui></li> |
-||||| <ul><li>- \[x] Docker</ui></li> |
+| Connectivity | Management | Security | Automation | Platforms |
+|---|---|---|---|---|
+| ✓ [Kernel WireGuard](https://docs.netbird.io/about-netbird/why-wireguard-with-netbird) | ✓ [Admin Web UI](https://github.com/netbirdio/dashboard) | ✓ [SSO & MFA support](https://docs.netbird.io/how-to/installation#running-net-bird-with-sso-login) | ✓ [Public API](https://docs.netbird.io/api) | ✓ [Linux](https://docs.netbird.io/get-started/install/linux) |
+| ✓ [Peer-to-peer connections](https://docs.netbird.io/about-netbird/how-netbird-works) | ✓ Auto peer discovery and configuration | ✓ [Access control: groups & rules](https://docs.netbird.io/how-to/manage-network-access) | ✓ [Setup keys for bulk provisioning](https://docs.netbird.io/how-to/register-machines-using-setup-keys) | ✓ [macOS](https://docs.netbird.io/get-started/install/macos) |
+| ✓ Connection relay fallback | ✓ [IdP integrations](https://docs.netbird.io/selfhosted/identity-providers) | ✓ [Activity logging](https://docs.netbird.io/how-to/audit-events-logging) | ✓ [Self-hosting quickstart script](https://docs.netbird.io/selfhosted/selfhosted-quickstart) | ✓ [Windows](https://docs.netbird.io/get-started/install/windows) |
+| ✓ [Routes to external networks](https://docs.netbird.io/how-to/routing-traffic-to-private-networks) | ✓ [Private DNS](https://docs.netbird.io/how-to/manage-dns-in-your-network) | ✓ [Traffic events](https://docs.netbird.io/manage/activity/traffic-events-logging) | ✓ [IdP groups sync with JWT](https://docs.netbird.io/manage/team/idp-sync) | ✓ [Android](https://docs.netbird.io/get-started/install/android) |
+| ✓ [Domain-based DNS routes](https://docs.netbird.io/manage/dns/dns-aliases-for-routed-networks) | ✓ [Custom DNS zones](https://docs.netbird.io/manage/dns/custom-zones) | ✓ [Device posture checks](https://docs.netbird.io/how-to/manage-posture-checks) | ✓ [Terraform provider](https://registry.terraform.io/providers/netbirdio/netbird/latest) | ✓ [Android TV](https://docs.netbird.io/get-started/install/android-tv) |
+| ✓ [Exit nodes](https://docs.netbird.io/manage/network-routes/use-cases/exit-nodes) | ✓ [Multiuser support](https://docs.netbird.io/how-to/add-users-to-your-network) | ✓ Peer-to-peer encryption | ✓ [Ansible collection](https://github.com/netbirdio/ansible-netbird) | ✓ [iOS](https://docs.netbird.io/get-started/install/ios) |
+| ✓ [IPv6 dual-stack overlay](https://docs.netbird.io/manage/settings/ipv6) | ✓ [Multi-account profile switching](https://docs.netbird.io/client/profiles) | ✓ [SSH with central access policies](https://docs.netbird.io/manage/peers/ssh) | | ✓ [Apple TV](https://docs.netbird.io/get-started/install/tvos) |
+| ✓ [Browser SSH & RDP](https://docs.netbird.io/manage/peers/browser-client) | | ✓ [Quantum-resistance with Rosenpass](https://netbird.io/knowledge-hub/the-first-quantum-resistant-mesh-vpn) | | ✓ FreeBSD |
+| ✓ [Reverse proxy with auto-TLS](https://docs.netbird.io/manage/reverse-proxy) | | ✓ [Periodic re-authentication](https://docs.netbird.io/how-to/enforce-periodic-user-authentication) | | ✓ [pfSense](https://docs.netbird.io/get-started/install/pfsense) |
+| | | | | ✓ [OPNsense](https://docs.netbird.io/get-started/install/opnsense) |
+| | | | | ✓ [MikroTik RouterOS](https://docs.netbird.io/use-cases/homelab/client-on-mikrotik-router) |
+| | | | | ✓ OpenWRT |
+| | | | | ✓ [Synology](https://docs.netbird.io/get-started/install/synology) |
+| | | | | ✓ [TrueNAS](https://docs.netbird.io/get-started/install/truenas) |
+| | | | | ✓ [Proxmox](https://docs.netbird.io/get-started/install/proxmox-ve) |
+| | | | | ✓ [Raspberry Pi](https://docs.netbird.io/get-started/install/raspberrypi) |
+| | | | | ✓ [Serverless](https://docs.netbird.io/how-to/netbird-on-faas) |
+| | | | | ✓ [Container](https://docs.netbird.io/get-started/install/docker) |
 
 ### Quickstart with NetBird Cloud
 
-- Download and install NetBird at [https://app.netbird.io/install](https://app.netbird.io/install)
-- Follow the steps to sign-up with Google, Microsoft, GitHub or your email address.
-- Check NetBird [admin UI](https://app.netbird.io/).
-- Add more machines.
+- Download and install NetBird at [https://app.netbird.io/install](https://app.netbird.io/install).
+- Follow the steps to sign up with Google, Microsoft, GitHub or your email address.
+- Check the NetBird [admin UI](https://app.netbird.io/).
 
 ### Quickstart with self-hosted NetBird
 
-> This is the quickest way to try self-hosted NetBird. It should take around 5 minutes to get started if you already have a public domain and a VM.
-Follow the [Advanced guide with a custom identity provider](https://docs.netbird.io/selfhosted/selfhosted-guide#advanced-guide-with-a-custom-identity-provider) for installations with different IDPs.
+This is the quickest way to try self-hosted NetBird. It should take around 5 minutes to get started if you already have a public domain and a VM. Follow the [Advanced guide with a custom identity provider](https://docs.netbird.io/selfhosted/selfhosted-guide#advanced-guide-with-a-custom-identity-provider) for installations with different IdPs.
 
 **Infrastructure requirements:**
-- A Linux VM with at least **1CPU** and **2GB** of memory.
-- The VM should be publicly accessible on TCP ports **80** and **443** and UDP port: **3478**.
-- **Public domain** name pointing to the VM.
+- A Linux VM with at least **1 CPU** and **2 GB** of memory.
+- The VM should be publicly accessible on TCP ports **80** and **443** and UDP port **3478**.
+- A **public domain** name pointing to the VM.
 
 **Software requirements:**
-- Docker installed on the VM with the docker-compose plugin ([Docker installation guide](https://docs.docker.com/engine/install/)) or docker with docker-compose in version 2 or higher.
-- [jq](https://jqlang.github.io/jq/) installed. In most distributions
-  Usually available in the official repositories and can be installed with `sudo apt install jq` or `sudo yum install jq`
-- [curl](https://curl.se/) installed.
-  Usually available in the official repositories and can be installed with `sudo apt install curl` or `sudo yum install curl`
+- Docker with the Compose plugin (Compose v2 or higher). See the [Docker installation guide](https://docs.docker.com/engine/install/).
 
 **Steps**
 - Download and run the installation script:
 ```bash
 export NETBIRD_DOMAIN=netbird.example.com; curl -fsSL https://github.com/netbirdio/netbird/releases/latest/download/getting-started.sh | bash
 ```
-- Once finished, you can manage the resources via `docker-compose`
 
 ### A bit on NetBird internals
--  Every machine in the network runs [NetBird Agent (or Client)](client/) that manages WireGuard.
--  Every agent connects to [Management Service](management/) that holds network state, manages peer IPs, and distributes network updates to agents (peers).
--  NetBird agent uses WebRTC ICE implemented in [pion/ice library](https://github.com/pion/ice) to discover connection candidates when establishing a peer-to-peer connection between machines.
--  Connection candidates are discovered with the help of [STUN](https://en.wikipedia.org/wiki/STUN) servers.
--  Agents negotiate a connection through [Signal Service](signal/) passing p2p encrypted messages with candidates.
--  Sometimes the NAT traversal is unsuccessful due to strict NATs (e.g. mobile carrier-grade NAT) and a p2p connection isn't possible. When this occurs the system falls back to a relay server called [TURN](https://en.wikipedia.org/wiki/Traversal_Using_Relays_around_NAT), and a secure WireGuard tunnel is established via the TURN server. 
- 
-[Coturn](https://github.com/coturn/coturn) is the one that has been successfully used for STUN and TURN in NetBird setups.
+- Every machine in the network runs the [NetBird agent](client/), which manages WireGuard.
+- Every agent connects to the [Management Service](management/), which holds network state, manages peer IPs, and distributes updates to agents.
+- Agents use ICE (via [pion/ice](https://github.com/pion/ice)) to discover connection candidates for peer-to-peer connections.
+- Candidates are discovered with the help of [STUN](https://en.wikipedia.org/wiki/STUN) servers.
+- Agents negotiate a connection through the [Signal Service](signal/), exchanging end-to-end encrypted messages with candidates.
+- When NAT traversal fails (e.g. mobile carrier-grade NAT) and a direct p2p connection isn't possible, the system falls back to a [Relay Service](relay/) and a secure WireGuard tunnel is established through it.
 
 <p float="left" align="middle">
-  <img src="https://docs.netbird.io/docs-static/img/about-netbird/high-level-dia.png" width="700"/>
+  <img src="https://docs.netbird.io/docs-static/img/about-netbird/high-level-dia.png" width="700" alt="NetBird high-level architecture diagram"/>
 </p>
 
 See a complete [architecture overview](https://docs.netbird.io/about-netbird/how-netbird-works#architecture) for details.
 
 ### Community projects
--  [NetBird installer script](https://github.com/physk/netbird-installer)
--  [NetBird ansible collection by Dominion Solutions](https://galaxy.ansible.com/ui/repo/published/dominion_solutions/netbird/)
--  [netbird-tui](https://github.com/n0pashkov/netbird-tui) — terminal UI for managing NetBird peers, routes, and settings
+- [NetBird installer script](https://github.com/physk/netbird-installer)
+- [netbird-tui](https://github.com/n0pashkov/netbird-tui) - terminal UI for managing NetBird peers, routes, and settings
+- [caddy-netbird](https://github.com/lixmal/caddy-netbird) - Caddy plugin that embeds a NetBird client for proxying HTTP and TCP/UDP traffic through NetBird networks
 
 **Note**: The `main` branch may be in an *unstable or even broken state* during development.
 For stable versions, see [releases](https://github.com/netbirdio/netbird/releases).
 
 ### Support acknowledgement
 
-In November 2022, NetBird joined the [StartUpSecure program](https://www.forschung-it-sicherheit-kommunikationssysteme.de/foerderung/bekanntmachungen/startup-secure) sponsored by The Federal Ministry of Education and Research of The Federal Republic of Germany. Together with [CISPA Helmholtz Center for Information Security](https://cispa.de/en) NetBird brings the security best practices and simplicity to private networking.
+In November 2022, NetBird joined the [StartUpSecure program](https://www.forschung-it-sicherheit-kommunikationssysteme.de/foerderung/bekanntmachungen/startup-secure) sponsored by the Federal Ministry of Education and Research of the Federal Republic of Germany. Together with the [CISPA Helmholtz Center for Information Security](https://cispa.de/en), NetBird brings security best practices and simplicity to private networking.
 
 ![CISPA_Logo_BLACK_EN_RZ_RGB (1)](https://user-images.githubusercontent.com/700848/203091324-c6d311a0-22b5-4b05-a288-91cbc6cdcc46.png)
 
-### Testimonials
-We use open-source technologies like [WireGuard®](https://www.wireguard.com/), [Pion ICE (WebRTC)](https://github.com/pion/ice), [Coturn](https://github.com/coturn/coturn), and [Rosenpass](https://rosenpass.eu). We very much appreciate the work these guys are doing and we'd greatly appreciate if you could support them in any way (e.g., by giving a star or a contribution).
+### Acknowledgements
+We build on open-source technologies like [WireGuard®](https://www.wireguard.com/), [Pion ICE](https://github.com/pion/ice), and [Rosenpass](https://rosenpass.eu). We greatly appreciate the work these projects are doing, and we'd love it if you could support them too (e.g., by starring or contributing).
 
 ### Legal
-This repository is licensed under BSD-3-Clause license that applies to all parts of the repository except for the directories management/, signal/ and relay/.
+This repository is licensed under the BSD-3-Clause license, which applies to all parts of the repository except for the directories management/, signal/ and relay/.
 Those directories are licensed under the GNU Affero General Public License version 3.0 (AGPLv3). See the respective LICENSE files inside each directory.
 
 _WireGuard_ and the _WireGuard_ logo are [registered trademarks](https://www.wireguard.com/trademark-policy/) of Jason A. Donenfeld.

client/cmd/status.go

@@ -43,16 +43,16 @@ func init() {
 	ipsFilterMap = make(map[string]struct{})
 	prefixNamesFilterMap = make(map[string]struct{})
 	statusCmd.PersistentFlags().BoolVarP(&detailFlag, "detail", "d", false, "display detailed status information in human-readable format")
-	statusCmd.PersistentFlags().BoolVar(&jsonFlag, "json", false, "display detailed status information in json format")
-	statusCmd.PersistentFlags().BoolVar(&yamlFlag, "yaml", false, "display detailed status information in yaml format")
-	statusCmd.PersistentFlags().BoolVar(&ipv4Flag, "ipv4", false, "display only NetBird IPv4 of this peer, e.g., --ipv4 will output 100.64.0.33")
-	statusCmd.PersistentFlags().BoolVar(&ipv6Flag, "ipv6", false, "display only NetBird IPv6 of this peer")
+	statusCmd.PersistentFlags().BoolVarP(&jsonFlag, "json", "j", false, "display detailed status information in json format")
+	statusCmd.PersistentFlags().BoolVarP(&yamlFlag, "yaml", "y", false, "display detailed status information in yaml format")
+	statusCmd.PersistentFlags().BoolVarP(&ipv4Flag, "ipv4", "4", false, "display only NetBird IPv4 of this peer, e.g., --ipv4 will output 100.64.0.33")
+	statusCmd.PersistentFlags().BoolVarP(&ipv6Flag, "ipv6", "6", false, "display only NetBird IPv6 of this peer")
 	statusCmd.MarkFlagsMutuallyExclusive("detail", "json", "yaml", "ipv4", "ipv6")
-	statusCmd.PersistentFlags().StringSliceVar(&ipsFilter, "filter-by-ips", []string{}, "filters the detailed output by a list of one or more IPs (v4 or v6), e.g., --filter-by-ips 100.64.0.100,fd00::1")
-	statusCmd.PersistentFlags().StringSliceVar(&prefixNamesFilter, "filter-by-names", []string{}, "filters the detailed output by a list of one or more peer FQDN or hostnames, e.g., --filter-by-names peer-a,peer-b.netbird.cloud")
-	statusCmd.PersistentFlags().StringVar(&statusFilter, "filter-by-status", "", "filters the detailed output by connection status(idle|connecting|connected), e.g., --filter-by-status connected")
-	statusCmd.PersistentFlags().StringVar(&connectionTypeFilter, "filter-by-connection-type", "", "filters the detailed output by connection type (P2P|Relayed), e.g., --filter-by-connection-type P2P")
-	statusCmd.PersistentFlags().StringVar(&checkFlag, "check", "", "run a health check and exit with code 0 on success, 1 on failure (live|ready|startup)")
+	statusCmd.PersistentFlags().StringSliceVarP(&ipsFilter, "filter-by-ips", "I", []string{}, "filters the detailed output by a list of one or more IPs (v4 or v6), e.g., --filter-by-ips 100.64.0.100,fd00::1")
+	statusCmd.PersistentFlags().StringSliceVarP(&prefixNamesFilter, "filter-by-names", "N", []string{}, "filters the detailed output by a list of one or more peer FQDN or hostnames, e.g., --filter-by-names peer-a,peer-b.netbird.cloud")
+	statusCmd.PersistentFlags().StringVarP(&statusFilter, "filter-by-status", "S", "", "filters the detailed output by connection status(idle|connecting|connected), e.g., --filter-by-status connected")
+	statusCmd.PersistentFlags().StringVarP(&connectionTypeFilter, "filter-by-connection-type", "T", "", "filters the detailed output by connection type (P2P|Relayed), e.g., --filter-by-connection-type P2P")
+	statusCmd.PersistentFlags().StringVarP(&checkFlag, "check", "C", "", "run a health check and exit with code 0 on success, 1 on failure (live|ready|startup)")
 }
 
 func statusFunc(cmd *cobra.Command, args []string) error {

client/cmd/testutil_test.go

@@ -11,7 +11,7 @@ import (
 	"go.opentelemetry.io/otel"
 	"google.golang.org/grpc"
 
-	"github.com/netbirdio/management-integrations/integrations"
+	"github.com/netbirdio/netbird/management/server/integrations/integrated_validator/validator"
 
 	nbcache "github.com/netbirdio/netbird/management/server/cache"
 
@@ -109,7 +109,7 @@ func startManagement(t *testing.T, config *config.Config, testFile string) (*grp
 		t.Fatal(err)
 	}
 
-	iv, _ := integrations.NewIntegratedValidator(ctx, peersmanager, settingsManagerMock, eventStore, cacheStore)
+	iv, _ := validator.NewIntegratedValidator(ctx, peersmanager, settingsManagerMock, eventStore, cacheStore)
 
 	metrics, err := telemetry.NewDefaultAppMetrics(ctx)
 	require.NoError(t, err)

client/embed/embed.go

@@ -12,6 +12,7 @@ import (
 	"sync"
 
 	"github.com/sirupsen/logrus"
+	wgdevice "golang.zx2c4.com/wireguard/device"
 	wgnetstack "golang.zx2c4.com/wireguard/tun/netstack"
 
 	"github.com/netbirdio/netbird/client/iface"
@@ -84,6 +85,12 @@ type Options struct {
 	DisableIPv6 bool
 	// BlockInbound blocks all inbound connections from peers
 	BlockInbound bool
+	// BlockLANAccess blocks the embedded peer from reaching the host's
+	// LAN (RFC 1918, link-local, loopback) when it's used as a routing
+	// peer. Mirrors profilemanager.ConfigInput.BlockLANAccess. Useful
+	// when the embedded client must never act as a stepping stone into
+	// the host's local network (e.g. the proxy's overlay peer).
+	BlockLANAccess bool
 	// WireguardPort is the port for the tunnel interface. Use 0 for a random port.
 	WireguardPort *int
 	// MTU is the MTU for the tunnel interface.
@@ -94,6 +101,26 @@ type Options struct {
 	MTU *uint16
 	// DNSLabels defines additional DNS labels configured in the peer.
 	DNSLabels []string
+	// Performance configures the tunnel's buffer pool cap and batch size.
+	Performance Performance
+}
+
+// Performance configures the embedded client's tunnel memory/throughput knobs.
+//
+// These settings are process-global: any non-nil field also becomes the
+// default for Clients constructed by later embed.New calls in the same
+// process. Nil fields are ignored.
+type Performance struct {
+	// PreallocatedBuffersPerPool caps the per-tunnel buffer pool. Zero
+	// leaves the pool unbounded. Lower values trade throughput for a
+	// tighter memory ceiling. May also be changed on a running Client via
+	// Client.SetPerformance, provided this field was nonzero at construction.
+	PreallocatedBuffersPerPool *uint32
+	// MaxBatchSize overrides the number of packets the tunnel reads or
+	// writes per syscall, which also bounds eager buffer allocation per
+	// worker. Zero uses the platform default. Applied at construction
+	// only; ignored by Client.SetPerformance.
+	MaxBatchSize *uint32
 }
 
 // validateCredentials checks that exactly one credential type is provided
@@ -175,6 +202,7 @@ func New(opts Options) (*Client, error) {
 		DisableClientRoutes: &opts.DisableClientRoutes,
 		DisableIPv6:         &opts.DisableIPv6,
 		BlockInbound:        &opts.BlockInbound,
+		BlockLANAccess:      &opts.BlockLANAccess,
 		WireguardPort:       opts.WireguardPort,
 		MTU:                 opts.MTU,
 		DNSLabels:           parsedLabels,
@@ -192,6 +220,13 @@ func New(opts Options) (*Client, error) {
 		config.PrivateKey = opts.PrivateKey
 	}
 
+	if opts.Performance.PreallocatedBuffersPerPool != nil {
+		wgdevice.SetPreallocatedBuffersPerPool(*opts.Performance.PreallocatedBuffersPerPool)
+	}
+	if opts.Performance.MaxBatchSize != nil {
+		wgdevice.SetMaxBatchSizeOverride(*opts.Performance.MaxBatchSize)
+	}
+
 	return &Client{
 		deviceName: opts.DeviceName,
 		setupKey:   opts.SetupKey,
@@ -336,7 +371,7 @@ func (c *Client) ListenTCP(address string) (net.Listener, error) {
 	if err != nil {
 		return nil, fmt.Errorf("split host port: %w", err)
 	}
-	listenAddr := fmt.Sprintf("%s:%s", addr, port)
+	listenAddr := net.JoinHostPort(addr.String(), port)
 
 	tcpAddr, err := net.ResolveTCPAddr("tcp", listenAddr)
 	if err != nil {
@@ -357,7 +392,7 @@ func (c *Client) ListenUDP(address string) (net.PacketConn, error) {
 	if err != nil {
 		return nil, fmt.Errorf("split host port: %w", err)
 	}
-	listenAddr := fmt.Sprintf("%s:%s", addr, port)
+	listenAddr := net.JoinHostPort(addr.String(), port)
 
 	udpAddr, err := net.ResolveUDPAddr("udp", listenAddr)
 	if err != nil {
@@ -405,6 +440,21 @@ func (c *Client) Expose(ctx context.Context, req ExposeRequest) (*ExposeSession,
 	}, nil
 }
 
+// IdentityForIP looks up a remote peer by its tunnel IP using the
+// embedded client's status recorder. Returns the peer's WireGuard public
+// key and FQDN. ok=false means the IP isn't in this client's peer
+// roster — callers should treat that as "unknown peer".
+func (c *Client) IdentityForIP(ip netip.Addr) (pubKey, fqdn string, ok bool) {
+	if !ip.IsValid() || c.recorder == nil {
+		return "", "", false
+	}
+	state, found := c.recorder.PeerStateByIP(ip.String())
+	if !found {
+		return "", "", false
+	}
+	return state.PubKey, state.FQDN, true
+}
+
 // Status returns the current status of the client.
 func (c *Client) Status() (peer.FullStatus, error) {
 	c.mu.Lock()
@@ -473,6 +523,25 @@ func (c *Client) VerifySSHHostKey(peerAddress string, key []byte) error {
 	return sshcommon.VerifyHostKey(storedKey, key, peerAddress)
 }
 
+// SetPerformance retunes a running Client. Only PreallocatedBuffersPerPool
+// takes effect, and only when it was nonzero at construction;
+// MaxBatchSize is construction-only and returns an error if set here.
+//
+// Returns ErrClientNotStarted / ErrEngineNotStarted if the Client is not
+// running yet.
+func (c *Client) SetPerformance(t Performance) error {
+	if t.MaxBatchSize != nil {
+		return errors.New("MaxBatchSize is construction-only and cannot be changed at runtime")
+	}
+	engine, err := c.getEngine()
+	if err != nil {
+		return err
+	}
+	return engine.SetPerformance(internal.Performance{
+		PreallocatedBuffersPerPool: t.PreallocatedBuffersPerPool,
+	})
+}
+
 // StartCapture begins capturing packets on this client's tunnel device.
 // Only one capture can be active at a time; starting a new one stops the previous.
 // Call StopCapture (or CaptureSession.Stop) to end it.

client/firewall/create.go

@@ -21,7 +21,7 @@ func NewFirewall(iface IFaceMapper, _ *statemanager.Manager, flowLogger nftypes.
 	}
 
 	// use userspace packet filtering firewall
-	fm, err := uspfilter.Create(iface, disableServerRoutes, flowLogger, mtu)
+	fm, err := uspfilter.Create(iface, nil, disableServerRoutes, flowLogger, mtu)
 	if err != nil {
 		return nil, err
 	}

client/firewall/create_linux.go

@@ -29,47 +29,80 @@ const (
 	NFTABLES
 )
 
-// SKIP_NFTABLES_ENV is the environment variable to skip nftables check
-const SKIP_NFTABLES_ENV = "NB_SKIP_NFTABLES_CHECK"
+// SkipNftablesEnv is the environment variable to skip nftables check
+const SkipNftablesEnv = "NB_SKIP_NFTABLES_CHECK"
+
+// errNoFirewallManager indicates no kernel firewall backend is present,
+// as opposed to a backend that exists but failed to create or initialize.
+var errNoFirewallManager = errors.New("no firewall manager found")
 
 // FWType is the type for the firewall type
 type FWType int
 
 func NewFirewall(iface IFaceMapper, stateManager *statemanager.Manager, flowLogger nftypes.FlowLogger, disableServerRoutes bool, mtu uint16) (firewall.Manager, error) {
-	// We run in userspace mode and force userspace firewall was requested. We don't attempt native firewall.
+	// We run in userspace mode and force userspace firewall was requested.
 	if iface.IsUserspaceBind() && forceUserspaceFirewall() {
+		nativeFw, err := createNativeFirewall(iface, stateManager, disableServerRoutes, mtu)
+		if err != nil {
+			log.Warnf("failed to create native firewall: %v. Proceeding without it", err)
+		}
+
 		log.Info("forcing userspace firewall")
-		return createUserspaceFirewall(iface, nil, disableServerRoutes, flowLogger, mtu)
+		return createUserspaceFirewall(iface, nativeFw, disableServerRoutes, flowLogger, mtu)
 	}
 
 	// Use native firewall for either kernel or userspace, the interface appears identical to netfilter
 	fm, err := createNativeFirewall(iface, stateManager, disableServerRoutes, mtu)
-
-	// Kernel cannot fall back to anything else, need to return error
-	if !iface.IsUserspaceBind() {
-		return fm, err
-	}
-
-	// Fall back to the userspace packet filter if native is unavailable
-	if err != nil {
-		log.Warnf("failed to create native firewall: %v. Proceeding with userspace", err)
+	switch {
+	case err == nil && !iface.IsUserspaceBind():
+		// Nothing to do, fall through
+	case err == nil && iface.IsUserspaceBind():
+		// Native firewall handles packet filtering, but the userspace WireGuard bind
+		// needs a device filter for DNS interception hooks. Install a minimal
+		// hooks-only filter that passes all traffic through to the kernel firewall.
+		if err := iface.SetFilter(&uspfilter.HooksFilter{}); err != nil {
+			log.Warnf("failed to set hooks filter, DNS via memory hooks will not work: %v", err)
+		}
+	case err != nil && !iface.IsUserspaceBind():
+		// Kernel cannot fall back to anything else, need to return error
+		return nil, err
+	case err != nil && iface.IsUserspaceBind():
+		// Fall back to the userspace packet filter if native is unavailable
+		logNativeFirewallUnavailable(err)
 		return createUserspaceFirewall(iface, nil, disableServerRoutes, flowLogger, mtu)
 	}
 
-	// Native firewall handles packet filtering, but the userspace WireGuard bind
-	// needs a device filter for DNS interception hooks. Install a minimal
-	// hooks-only filter that passes all traffic through to the kernel firewall.
-	if err := iface.SetFilter(&uspfilter.HooksFilter{}); err != nil {
-		log.Warnf("failed to set hooks filter, DNS via memory hooks will not work: %v", err)
-	}
-
 	return fm, nil
 }
 
+// createUserspaceFirewall builds the userspace packet filter, optionally
+// backed by a native firewall, and allows netbird interface traffic.
+func createUserspaceFirewall(iface IFaceMapper, nativeFw firewall.Manager, disableServerRoutes bool, flowLogger nftypes.FlowLogger, mtu uint16) (firewall.Manager, error) {
+	fm, err := uspfilter.Create(iface, nativeFw, disableServerRoutes, flowLogger, mtu)
+	if err != nil {
+		return nil, err
+	}
+
+	if err := fm.AllowNetbird(); err != nil {
+		log.Errorf("failed to allow netbird interface traffic: %v", err)
+	}
+	return fm, nil
+}
+
+// logNativeFirewallUnavailable logs the fallback to userspace at info level
+// when no kernel firewall backend exists, and at warn level otherwise.
+func logNativeFirewallUnavailable(err error) {
+	if errors.Is(err, errNoFirewallManager) {
+		log.Infof("no native firewall backend available: %v. Proceeding with userspace", err)
+	} else {
+		log.Warnf("failed to create native firewall: %v. Proceeding with userspace", err)
+	}
+}
+
 func createNativeFirewall(iface IFaceMapper, stateManager *statemanager.Manager, routes bool, mtu uint16) (firewall.Manager, error) {
 	fm, err := createFW(iface, mtu)
 	if err != nil {
-		return nil, fmt.Errorf("create firewall: %s", err)
+		return nil, fmt.Errorf("create firewall: %w", err)
 	}
 
 	if err = fm.Init(stateManager); err != nil {
@@ -88,29 +121,10 @@ func createFW(iface IFaceMapper, mtu uint16) (firewall.Manager, error) {
 		log.Info("creating an nftables firewall manager")
 		return nbnftables.Create(iface, mtu)
 	default:
-		log.Info("no firewall manager found, trying to use userspace packet filtering firewall")
-		return nil, errors.New("no firewall manager found")
+		return nil, errNoFirewallManager
 	}
 }
 
-func createUserspaceFirewall(iface IFaceMapper, fm firewall.Manager, disableServerRoutes bool, flowLogger nftypes.FlowLogger, mtu uint16) (firewall.Manager, error) {
-	var errUsp error
-	if fm != nil {
-		fm, errUsp = uspfilter.CreateWithNativeFirewall(iface, fm, disableServerRoutes, flowLogger, mtu)
-	} else {
-		fm, errUsp = uspfilter.Create(iface, disableServerRoutes, flowLogger, mtu)
-	}
-
-	if errUsp != nil {
-		return nil, fmt.Errorf("create userspace firewall: %s", errUsp)
-	}
-
-	if err := fm.AllowNetbird(); err != nil {
-		log.Errorf("failed to allow netbird interface traffic: %v", err)
-	}
-	return fm, nil
-}
-
 // check returns the firewall type based on common lib checks. It returns UNKNOWN if no firewall is found.
 func check() FWType {
 	useIPTABLES := false
@@ -132,35 +146,38 @@ func check() FWType {
 		}
 	}
 
-	nf := nftables.Conn{}
-	if chains, err := nf.ListChains(); err == nil && os.Getenv(SKIP_NFTABLES_ENV) != "true" {
-		if !useIPTABLES {
-			return NFTABLES
-		}
-
-		// search for chains where table is filter
-		// if we find one, we assume that nftables manager can be used with iptables
-		for _, chain := range chains {
-			if chain.Table.Name == "filter" {
+	// Honor the skip env before probing nftables at all.
+	if os.Getenv(SkipNftablesEnv) != "true" {
+		nf := nftables.Conn{}
+		if chains, err := nf.ListChains(); err == nil {
+			if !useIPTABLES {
 				return NFTABLES
 			}
-		}
 
-		// check tables for the following constraints:
-		// 1. there is no chain in nftables for the filter table and there is at least one chain in iptables, we assume that nftables manager can not be used
-		// 2. there is no tables or more than one table, we assume that nftables manager can be used
-		// 3. there is only one table and its name is filter, we assume that nftables manager can not be used, since there was no chain in it
-		// 4. if we find an error we log and continue with iptables check
-		nbTablesList, err := nf.ListTables()
-		switch {
-		case err == nil && len(iptablesChains) > 0:
-			return IPTABLES
-		case err == nil && len(nbTablesList) != 1:
-			return NFTABLES
-		case err == nil && len(nbTablesList) == 1 && nbTablesList[0].Name == "filter":
-			return IPTABLES
-		case err != nil:
-			log.Errorf("failed to list nftables tables on fw manager discovery: %s", err)
+			// search for chains where table is filter
+			// if we find one, we assume that nftables manager can be used with iptables
+			for _, chain := range chains {
+				if chain.Table.Name == "filter" {
+					return NFTABLES
+				}
+			}
+
+			// check tables for the following constraints:
+			// 1. there is no chain in nftables for the filter table and there is at least one chain in iptables, we assume that nftables manager can not be used
+			// 2. there is no tables or more than one table, we assume that nftables manager can be used
+			// 3. there is only one table and its name is filter, we assume that nftables manager can not be used, since there was no chain in it
+			// 4. if we find an error we log and continue with iptables check
+			nbTablesList, err := nf.ListTables()
+			switch {
+			case err == nil && len(iptablesChains) > 0:
+				return IPTABLES
+			case err == nil && len(nbTablesList) != 1:
+				return NFTABLES
+			case err == nil && len(nbTablesList) == 1 && nbTablesList[0].Name == "filter":
+				return IPTABLES
+			case err != nil:
+				log.Errorf("failed to list nftables tables on fw manager discovery: %s", err)
+			}
 		}
 	}
 

client/firewall/iptables/acl_linux.go

@@ -1,554 +0,0 @@
-package iptables
-
-import (
-	"errors"
-	"fmt"
-	"net"
-	"slices"
-
-	"github.com/coreos/go-iptables/iptables"
-	"github.com/google/uuid"
-	ipset "github.com/lrh3321/ipset-go"
-	log "github.com/sirupsen/logrus"
-
-	firewall "github.com/netbirdio/netbird/client/firewall/manager"
-	"github.com/netbirdio/netbird/client/internal/statemanager"
-	nbnet "github.com/netbirdio/netbird/client/net"
-)
-
-const (
-	tableName = "filter"
-
-	// rules chains contains the effective ACL rules
-	chainNameInputRules = "NETBIRD-ACL-INPUT"
-
-	// mangleFwdKey is the entries map key for mangle FORWARD guard rules that prevent
-	// external DNAT from bypassing ACL rules.
-	mangleFwdKey = "MANGLE-FORWARD"
-)
-
-type aclEntries map[string][][]string
-
-type entry struct {
-	spec     []string
-	position int
-}
-
-type aclManager struct {
-	iptablesClient  *iptables.IPTables
-	wgIface         iFaceMapper
-	entries         aclEntries
-	optionalEntries map[string][]entry
-	ipsetStore      *ipsetStore
-	v6              bool
-
-	stateManager *statemanager.Manager
-}
-
-func newAclManager(iptablesClient *iptables.IPTables, wgIface iFaceMapper) (*aclManager, error) {
-	return &aclManager{
-		iptablesClient:  iptablesClient,
-		wgIface:         wgIface,
-		entries:         make(map[string][][]string),
-		optionalEntries: make(map[string][]entry),
-		ipsetStore:      newIpsetStore(),
-		v6:              iptablesClient.Proto() == iptables.ProtocolIPv6,
-	}, nil
-}
-
-func (m *aclManager) init(stateManager *statemanager.Manager) error {
-	m.stateManager = stateManager
-
-	m.seedInitialEntries()
-	m.seedInitialOptionalEntries()
-
-	if err := m.cleanChains(); err != nil {
-		return fmt.Errorf("clean chains: %w", err)
-	}
-
-	if err := m.createDefaultChains(); err != nil {
-		return fmt.Errorf("create default chains: %w", err)
-	}
-
-	m.updateState()
-
-	return nil
-}
-
-func (m *aclManager) AddPeerFiltering(
-	id []byte,
-	ip net.IP,
-	protocol firewall.Protocol,
-	sPort *firewall.Port,
-	dPort *firewall.Port,
-	action firewall.Action,
-	ipsetName string,
-) ([]firewall.Rule, error) {
-	chain := chainNameInputRules
-
-	ipsetName = transformIPsetName(ipsetName, sPort, dPort, action)
-	if m.v6 && ipsetName != "" {
-		ipsetName += "-v6"
-	}
-	proto := protoForFamily(protocol, m.v6)
-	specs := filterRuleSpecs(ip, proto, sPort, dPort, action, ipsetName)
-
-	mangleSpecs := slices.Clone(specs)
-	mangleSpecs = append(mangleSpecs,
-		"-i", m.wgIface.Name(),
-		"-m", "addrtype", "--dst-type", "LOCAL",
-		"-j", "MARK", "--set-xmark", fmt.Sprintf("%#x", nbnet.PreroutingFwmarkRedirected),
-	)
-
-	specs = append(specs, "-j", actionToStr(action))
-	if ipsetName != "" {
-		if ipList, ipsetExists := m.ipsetStore.ipset(ipsetName); ipsetExists {
-			if err := m.addToIPSet(ipsetName, ip); err != nil {
-				return nil, fmt.Errorf("add IP to ipset: %w", err)
-			}
-			// if ruleset already exists it means we already have the firewall rule
-			// so we need to update IPs in the ruleset and return new fw.Rule object for ACL manager.
-			ipList.addIP(ip.String())
-			return []firewall.Rule{&Rule{
-				ruleID:    uuid.New().String(),
-				ipsetName: ipsetName,
-				ip:        ip.String(),
-				chain:     chain,
-				specs:     specs,
-				v6:        m.v6,
-			}}, nil
-		}
-
-		if err := m.flushIPSet(ipsetName); err != nil {
-			if errors.Is(err, ipset.ErrSetNotExist) {
-				log.Debugf("flush ipset %s before use: %v", ipsetName, err)
-			} else {
-				log.Errorf("flush ipset %s before use: %v", ipsetName, err)
-			}
-		}
-		if err := m.createIPSet(ipsetName); err != nil {
-			return nil, fmt.Errorf("create ipset: %w", err)
-		}
-		if err := m.addToIPSet(ipsetName, ip); err != nil {
-			return nil, fmt.Errorf("add IP to ipset: %w", err)
-		}
-
-		ipList := newIpList(ip.String())
-		m.ipsetStore.addIpList(ipsetName, ipList)
-	}
-
-	ok, err := m.iptablesClient.Exists(tableFilter, chain, specs...)
-	if err != nil {
-		return nil, fmt.Errorf("failed to check rule: %w", err)
-	}
-	if ok {
-		return nil, fmt.Errorf("rule already exists")
-	}
-
-	// Insert DROP rules at the beginning, append ACCEPT rules at the end
-	if action == firewall.ActionDrop {
-		// Insert at the beginning of the chain (position 1)
-		err = m.iptablesClient.Insert(tableFilter, chain, 1, specs...)
-	} else {
-		err = m.iptablesClient.Append(tableFilter, chain, specs...)
-	}
-	if err != nil {
-		return nil, err
-	}
-
-	if err := m.iptablesClient.Append(tableMangle, chainRTPRE, mangleSpecs...); err != nil {
-		log.Errorf("failed to add mangle rule: %v", err)
-		mangleSpecs = nil
-	}
-
-	rule := &Rule{
-		ruleID:      uuid.New().String(),
-		specs:       specs,
-		mangleSpecs: mangleSpecs,
-		ipsetName:   ipsetName,
-		ip:          ip.String(),
-		chain:       chain,
-		v6:          m.v6,
-	}
-
-	m.updateState()
-
-	return []firewall.Rule{rule}, nil
-}
-
-// DeletePeerRule from the firewall by rule definition
-func (m *aclManager) DeletePeerRule(rule firewall.Rule) error {
-	r, ok := rule.(*Rule)
-	if !ok {
-		return fmt.Errorf("invalid rule type")
-	}
-
-	shouldDestroyIpset := false
-	if ipsetList, ok := m.ipsetStore.ipset(r.ipsetName); ok {
-		// delete IP from ruleset IPs list and ipset
-		if _, ok := ipsetList.ips[r.ip]; ok {
-			ip := net.ParseIP(r.ip)
-			if ip == nil {
-				return fmt.Errorf("parse IP %s", r.ip)
-			}
-			if err := m.delFromIPSet(r.ipsetName, ip); err != nil {
-				return fmt.Errorf("delete ip from ipset: %w", err)
-			}
-			delete(ipsetList.ips, r.ip)
-		}
-
-		// if after delete, set still contains other IPs,
-		// no need to delete firewall rule and we should exit here
-		if len(ipsetList.ips) != 0 {
-			return nil
-		}
-
-		// we delete last IP from the set, that means we need to delete
-		// set itself and associated firewall rule too
-		m.ipsetStore.deleteIpset(r.ipsetName)
-		shouldDestroyIpset = true
-	}
-
-	if err := m.iptablesClient.Delete(tableName, r.chain, r.specs...); err != nil {
-		return fmt.Errorf("failed to delete rule: %s, %v: %w", r.chain, r.specs, err)
-	}
-
-	if r.mangleSpecs != nil {
-		if err := m.iptablesClient.Delete(tableMangle, chainRTPRE, r.mangleSpecs...); err != nil {
-			log.Errorf("failed to delete mangle rule: %v", err)
-		}
-	}
-
-	if shouldDestroyIpset {
-		if err := m.destroyIPSet(r.ipsetName); err != nil {
-			if errors.Is(err, ipset.ErrBusy) || errors.Is(err, ipset.ErrSetNotExist) {
-				log.Debugf("destroy empty ipset: %v", err)
-			} else {
-				log.Errorf("destroy empty ipset: %v", err)
-			}
-		}
-	}
-
-	m.updateState()
-
-	return nil
-}
-
-func (m *aclManager) Reset() error {
-	if err := m.cleanChains(); err != nil {
-		return fmt.Errorf("clean chains: %w", err)
-	}
-
-	m.updateState()
-
-	return nil
-}
-
-// todo write less destructive cleanup mechanism
-func (m *aclManager) cleanChains() error {
-	ok, err := m.iptablesClient.ChainExists(tableName, chainNameInputRules)
-	if err != nil {
-		log.Debugf("failed to list chains: %s", err)
-		return err
-	}
-	if ok {
-		for _, rule := range m.entries["INPUT"] {
-			err := m.iptablesClient.DeleteIfExists(tableName, "INPUT", rule...)
-			if err != nil {
-				log.Errorf("failed to delete rule: %v, %s", rule, err)
-			}
-		}
-
-		for _, rule := range m.entries["FORWARD"] {
-			err := m.iptablesClient.DeleteIfExists(tableName, "FORWARD", rule...)
-			if err != nil {
-				log.Errorf("failed to delete rule: %v, %s", rule, err)
-			}
-		}
-
-		err = m.iptablesClient.ClearAndDeleteChain(tableName, chainNameInputRules)
-		if err != nil {
-			log.Debugf("failed to clear and delete %s chain: %s", chainNameInputRules, err)
-			return err
-		}
-	}
-
-	ok, err = m.iptablesClient.ChainExists("mangle", "PREROUTING")
-	if err != nil {
-		return fmt.Errorf("list chains: %w", err)
-	}
-	if ok {
-		for _, rule := range m.entries["PREROUTING"] {
-			err := m.iptablesClient.DeleteIfExists("mangle", "PREROUTING", rule...)
-			if err != nil {
-				log.Errorf("failed to delete rule: %v, %s", rule, err)
-			}
-		}
-	}
-
-	for _, rule := range m.entries[mangleFwdKey] {
-		if err := m.iptablesClient.DeleteIfExists(tableMangle, chainFORWARD, rule...); err != nil {
-			log.Errorf("failed to delete mangle FORWARD guard rule: %v, %s", rule, err)
-		}
-	}
-
-	for _, ipsetName := range m.ipsetStore.ipsetNames() {
-		if err := m.flushIPSet(ipsetName); err != nil {
-			if errors.Is(err, ipset.ErrSetNotExist) {
-				log.Debugf("flush ipset %q during reset: %v", ipsetName, err)
-			} else {
-				log.Errorf("flush ipset %q during reset: %v", ipsetName, err)
-			}
-		}
-		if err := m.destroyIPSet(ipsetName); err != nil {
-			if errors.Is(err, ipset.ErrBusy) || errors.Is(err, ipset.ErrSetNotExist) {
-				log.Debugf("destroy ipset %q during reset: %v", ipsetName, err)
-			} else {
-				log.Errorf("destroy ipset %q during reset: %v", ipsetName, err)
-			}
-		}
-		m.ipsetStore.deleteIpset(ipsetName)
-	}
-
-	return nil
-}
-
-func (m *aclManager) createDefaultChains() error {
-	// chain netbird-acl-input-rules
-	if err := m.iptablesClient.NewChain(tableName, chainNameInputRules); err != nil {
-		log.Debugf("failed to create '%s' chain: %s", chainNameInputRules, err)
-		return err
-	}
-
-	for chainName, rules := range m.entries {
-		// mangle FORWARD guard rules are handled separately below
-		if chainName == mangleFwdKey {
-			continue
-		}
-		for _, rule := range rules {
-			if err := m.iptablesClient.InsertUnique(tableName, chainName, 1, rule...); err != nil {
-				log.Debugf("failed to create input chain jump rule: %s", err)
-				return err
-			}
-		}
-	}
-
-	for chainName, entries := range m.optionalEntries {
-		for _, entry := range entries {
-			if err := m.iptablesClient.InsertUnique(tableName, chainName, entry.position, entry.spec...); err != nil {
-				log.Errorf("failed to insert optional entry %v: %v", entry.spec, err)
-				continue
-			}
-			m.entries[chainName] = append(m.entries[chainName], entry.spec)
-		}
-	}
-	clear(m.optionalEntries)
-
-	// Insert mangle FORWARD guard rules to prevent external DNAT bypass.
-	for _, rule := range m.entries[mangleFwdKey] {
-		if err := m.iptablesClient.AppendUnique(tableMangle, chainFORWARD, rule...); err != nil {
-			log.Errorf("failed to add mangle FORWARD guard rule: %v", err)
-		}
-	}
-
-	return nil
-}
-
-// seedInitialEntries adds default rules to the entries map, rules are inserted on pos 1, hence the order is reversed.
-// We want to make sure our traffic is not dropped by existing rules.
-
-// The existing FORWARD rules/policies decide outbound traffic towards our interface.
-// In case the FORWARD policy is set to "drop", we add an established/related rule to allow return traffic for the inbound rule.
-func (m *aclManager) seedInitialEntries() {
-	established := getConntrackEstablished()
-
-	m.appendToEntries("INPUT", []string{"-i", m.wgIface.Name(), "-j", "DROP"})
-	m.appendToEntries("INPUT", []string{"-i", m.wgIface.Name(), "-j", chainNameInputRules})
-	m.appendToEntries("INPUT", append([]string{"-i", m.wgIface.Name()}, established...))
-
-	// Inbound is handled by our ACLs, the rest is dropped.
-	// For outbound we respect the FORWARD policy. However, we need to allow established/related traffic for inbound rules.
-	m.appendToEntries("FORWARD", []string{"-i", m.wgIface.Name(), "-j", "DROP"})
-
-	m.appendToEntries("FORWARD", []string{"-o", m.wgIface.Name(), "-j", chainRTFWDOUT})
-	m.appendToEntries("FORWARD", []string{"-i", m.wgIface.Name(), "-j", chainRTFWDIN})
-
-	// Mangle FORWARD guard: when external DNAT redirects traffic from the wg interface, it
-	// traverses FORWARD instead of INPUT, bypassing ACL rules. ACCEPT rules in filter FORWARD
-	// can be inserted above ours. Mangle runs before filter, so these guard rules enforce the
-	// ACL mark check where it cannot be overridden.
-	m.appendToEntries(mangleFwdKey, []string{
-		"-i", m.wgIface.Name(),
-		"-m", "conntrack", "--ctstate", "RELATED,ESTABLISHED",
-		"-j", "ACCEPT",
-	})
-	m.appendToEntries(mangleFwdKey, []string{
-		"-i", m.wgIface.Name(),
-		"-m", "conntrack", "--ctstate", "DNAT",
-		"-m", "mark", "!", "--mark", fmt.Sprintf("%#x", nbnet.PreroutingFwmarkRedirected),
-		"-j", "DROP",
-	})
-}
-
-func (m *aclManager) seedInitialOptionalEntries() {
-	m.optionalEntries["FORWARD"] = []entry{
-		{
-			spec:     []string{"-m", "mark", "--mark", fmt.Sprintf("%#x", nbnet.PreroutingFwmarkRedirected), "-j", "ACCEPT"},
-			position: 2,
-		},
-	}
-}
-
-func (m *aclManager) appendToEntries(chainName string, spec []string) {
-	m.entries[chainName] = append(m.entries[chainName], spec)
-}
-
-func (m *aclManager) updateState() {
-	if m.stateManager == nil {
-		return
-	}
-
-	var currentState *ShutdownState
-	if existing := m.stateManager.GetState(currentState); existing != nil {
-		if existingState, ok := existing.(*ShutdownState); ok {
-			currentState = existingState
-		}
-	}
-	if currentState == nil {
-		currentState = &ShutdownState{}
-	}
-
-	currentState.Lock()
-	defer currentState.Unlock()
-
-	if m.v6 {
-		currentState.ACLEntries6 = m.entries
-		currentState.ACLIPsetStore6 = m.ipsetStore
-	} else {
-		currentState.ACLEntries = m.entries
-		currentState.ACLIPsetStore = m.ipsetStore
-	}
-
-	if err := m.stateManager.UpdateState(currentState); err != nil {
-		log.Errorf("failed to update state: %v", err)
-	}
-}
-
-// filterRuleSpecs returns the specs of a filtering rule
-// protoForFamily translates ICMP to ICMPv6 for ip6tables.
-// ip6tables requires "ipv6-icmp" (or "icmpv6") instead of "icmp".
-func protoForFamily(protocol firewall.Protocol, v6 bool) string {
-	if v6 && protocol == firewall.ProtocolICMP {
-		return "ipv6-icmp"
-	}
-	return string(protocol)
-}
-
-func filterRuleSpecs(ip net.IP, protocol string, sPort, dPort *firewall.Port, action firewall.Action, ipsetName string) (specs []string) {
-	// don't use IP matching if IP is 0.0.0.0
-	matchByIP := !ip.IsUnspecified()
-
-	if matchByIP {
-		if ipsetName != "" {
-			specs = append(specs, "-m", "set", "--match-set", ipsetName, "src")
-		} else {
-			specs = append(specs, "-s", ip.String())
-		}
-	}
-	if protocol != "all" {
-		specs = append(specs, "-p", protocol)
-	}
-	specs = append(specs, applyPort("--sport", sPort)...)
-	specs = append(specs, applyPort("--dport", dPort)...)
-	return specs
-}
-
-func actionToStr(action firewall.Action) string {
-	if action == firewall.ActionAccept {
-		return "ACCEPT"
-	}
-	return "DROP"
-}
-
-func transformIPsetName(ipsetName string, sPort, dPort *firewall.Port, action firewall.Action) string {
-	if ipsetName == "" {
-		return ""
-	}
-
-	actionSuffix := ""
-	if action == firewall.ActionDrop {
-		actionSuffix = "-drop"
-	}
-
-	switch {
-	case sPort != nil && dPort != nil:
-		return ipsetName + "-sport-dport" + actionSuffix
-	case sPort != nil:
-		return ipsetName + "-sport" + actionSuffix
-	case dPort != nil:
-		return ipsetName + "-dport" + actionSuffix
-	default:
-		return ipsetName + actionSuffix
-	}
-}
-
-func (m *aclManager) createIPSet(name string) error {
-	opts := ipset.CreateOptions{
-		Replace: true,
-	}
-	if m.v6 {
-		opts.Family = ipset.FamilyIPV6
-	}
-
-	if err := ipset.Create(name, ipset.TypeHashNet, opts); err != nil {
-		return fmt.Errorf("create ipset %s: %w", name, err)
-	}
-
-	log.Debugf("created ipset %s with type hash:net", name)
-	return nil
-}
-
-func (m *aclManager) addToIPSet(name string, ip net.IP) error {
-	cidr := uint8(32)
-	if ip.To4() == nil {
-		cidr = 128
-	}
-
-	entry := &ipset.Entry{
-		IP:      ip,
-		CIDR:    cidr,
-		Replace: true,
-	}
-
-	if err := ipset.Add(name, entry); err != nil {
-		return fmt.Errorf("add IP to ipset %s: %w", name, err)
-	}
-
-	return nil
-}
-
-func (m *aclManager) delFromIPSet(name string, ip net.IP) error {
-	cidr := uint8(32)
-	if ip.To4() == nil {
-		cidr = 128
-	}
-
-	entry := &ipset.Entry{
-		IP:   ip,
-		CIDR: cidr,
-	}
-
-	if err := ipset.Del(name, entry); err != nil {
-		return fmt.Errorf("delete IP from ipset %s: %w", name, err)
-	}
-
-	return nil
-}
-
-func (m *aclManager) flushIPSet(name string) error {
-	return ipset.Flush(name)
-}
-
-func (m *aclManager) destroyIPSet(name string) error {
-	return ipset.Destroy(name)
-}

client/firewall/iptables/chains_linux.go

@@ -0,0 +1,352 @@
+//go:build !android
+
+package iptables
+
+import (
+	"fmt"
+
+	"github.com/hashicorp/go-multierror"
+	log "github.com/sirupsen/logrus"
+
+	nberrors "github.com/netbirdio/netbird/client/errors"
+	firewall "github.com/netbirdio/netbird/client/firewall/manager"
+	nbnet "github.com/netbirdio/netbird/client/net"
+)
+
+func (r *family) createContainers() error {
+	for _, chainInfo := range []struct {
+		chain string
+		table string
+	}{
+		{chainRTFwdIn, tableFilter},
+		{chainRTFwdOut, tableFilter},
+		{chainRTPre, tableMangle},
+		{chainRTNAT, tableNat},
+		{chainRTRdr, tableNat},
+		{chainRTMSSClamp, tableMangle},
+	} {
+		// Fallback: clear chains that survived an unclean shutdown.
+		if ok, _ := r.iptablesClient.ChainExists(chainInfo.table, chainInfo.chain); ok {
+			if err := r.iptablesClient.ClearAndDeleteChain(chainInfo.table, chainInfo.chain); err != nil {
+				log.Warnf("clear stale chain %s in %s: %v", chainInfo.chain, chainInfo.table, err)
+			}
+		}
+		if err := r.iptablesClient.NewChain(chainInfo.table, chainInfo.chain); err != nil {
+			return fmt.Errorf("create chain %s in table %s: %w", chainInfo.chain, chainInfo.table, err)
+		}
+	}
+
+	if err := r.insertEstablishedRule(chainRTFwdIn); err != nil {
+		return fmt.Errorf("insert established rule: %w", err)
+	}
+
+	if err := r.insertEstablishedRule(chainRTFwdOut); err != nil {
+		return fmt.Errorf("insert established rule: %w", err)
+	}
+
+	if err := r.addPostroutingRules(); err != nil {
+		return fmt.Errorf("add static nat rules: %w", err)
+	}
+
+	if err := r.addJumpRules(); err != nil {
+		return fmt.Errorf("add jump rules: %w", err)
+	}
+
+	if err := r.addMSSClampingRules(); err != nil {
+		log.Errorf("failed to add MSS clamping rules: %s", err)
+	}
+
+	return nil
+}
+
+func (r *family) addJumpRules() error {
+	// Jump to nat chain
+	natRule := []string{"-j", chainRTNAT}
+	if err := r.iptablesClient.Insert(tableNat, chainPostrouting, 1, natRule...); err != nil {
+		return fmt.Errorf("add nat postrouting jump rule: %w", err)
+	}
+	r.rules[jumpNATPost] = natRule
+
+	// Jump to mangle prerouting chain
+	preRule := []string{"-j", chainRTPre}
+	if err := r.iptablesClient.Insert(tableMangle, chainPrerouting, 1, preRule...); err != nil {
+		return fmt.Errorf("add mangle prerouting jump rule: %w", err)
+	}
+	r.rules[jumpManglePre] = preRule
+
+	// Jump to nat prerouting chain
+	rdrRule := []string{"-j", chainRTRdr}
+	if err := r.iptablesClient.Insert(tableNat, chainPrerouting, 1, rdrRule...); err != nil {
+		return fmt.Errorf("add nat prerouting jump rule: %w", err)
+	}
+	r.rules[jumpNATPre] = rdrRule
+
+	return nil
+}
+
+func (r *family) setupDataPlaneMark() error {
+	var merr *multierror.Error
+	preRule := []string{
+		"-i", r.wgIface.Name(),
+		"-m", "conntrack", "--ctstate", "NEW",
+		"-j", "CONNMARK", "--set-mark", fmt.Sprintf("%#x", nbnet.DataPlaneMarkIn),
+	}
+
+	if err := r.iptablesClient.AppendUnique(tableMangle, chainPrerouting, preRule...); err != nil {
+		merr = multierror.Append(merr, fmt.Errorf("add mangle prerouting rule: %w", err))
+	} else {
+		r.rules[markManglePre] = preRule
+	}
+
+	postRule := []string{
+		"-o", r.wgIface.Name(),
+		"-m", "conntrack", "--ctstate", "NEW",
+		"-j", "CONNMARK", "--set-mark", fmt.Sprintf("%#x", nbnet.DataPlaneMarkOut),
+	}
+
+	if err := r.iptablesClient.AppendUnique(tableMangle, chainPostrouting, postRule...); err != nil {
+		merr = multierror.Append(merr, fmt.Errorf("add mangle postrouting rule: %w", err))
+	} else {
+		r.rules[markManglePost] = postRule
+	}
+
+	return nberrors.FormatErrorOrNil(merr)
+}
+
+// seedInitialEntries adds default rules to the entries map. Rules are
+// inserted at position 1, so the order here is reversed.
+//
+// Existing FORWARD policy decides outbound traffic towards our
+// interface. If FORWARD policy is "drop", we add an
+// established/related rule to allow return traffic for inbound rules.
+func (r *family) seedInitialEntries() {
+	established := getConntrackEstablished()
+
+	r.appendToEntries(chainInput, []string{"-i", r.wgIface.Name(), "-j", "DROP"})
+	r.appendToEntries(chainInput, []string{"-i", r.wgIface.Name(), "-j", chainACLInput})
+	r.appendToEntries(chainInput, append([]string{"-i", r.wgIface.Name()}, established...))
+
+	r.appendToEntries(chainForward, []string{"-i", r.wgIface.Name(), "-j", "DROP"})
+	r.appendToEntries(chainForward, []string{"-o", r.wgIface.Name(), "-j", chainRTFwdOut})
+	r.appendToEntries(chainForward, []string{"-i", r.wgIface.Name(), "-j", chainRTFwdIn})
+
+	// Mangle FORWARD guard: when external DNAT redirects traffic from
+	// the wg interface, it traverses FORWARD instead of INPUT,
+	// bypassing ACL rules. ACCEPT rules in filter FORWARD can be
+	// inserted above ours. Mangle runs before filter, so these guard
+	// rules enforce the ACL mark check where it cannot be overridden.
+	r.appendToEntries(mangleForwardKey, []string{
+		"-i", r.wgIface.Name(),
+		"-m", "conntrack", "--ctstate", "RELATED,ESTABLISHED",
+		"-j", "ACCEPT",
+	})
+	r.appendToEntries(mangleForwardKey, []string{
+		"-i", r.wgIface.Name(),
+		"-m", "conntrack", "--ctstate", "DNAT",
+		"-m", "mark", "!", "--mark", fmt.Sprintf("%#x", nbnet.PreroutingFwmarkRedirected),
+		"-j", "DROP",
+	})
+}
+
+func (r *family) seedInitialOptionalEntries() {
+	r.optionalEntries[chainForward] = []entry{
+		{
+			spec:     []string{"-m", "mark", "--mark", fmt.Sprintf("%#x", nbnet.PreroutingFwmarkRedirected), "-j", "ACCEPT"},
+			position: 2,
+		},
+	}
+}
+
+func (r *family) appendToEntries(chain chainKey, spec ruleSpec) {
+	r.entries[chain] = append(r.entries[chain], spec)
+}
+
+func (r *family) createDefaultChains() error {
+	if err := r.iptablesClient.NewChain(tableName, chainACLInput); err != nil {
+		return fmt.Errorf("create %s chain: %w", chainACLInput, err)
+	}
+
+	for chain, rules := range r.entries {
+		// mangle FORWARD guard rules are handled separately below
+		if chain == mangleForwardKey {
+			continue
+		}
+		for _, rule := range rules {
+			if err := r.iptablesClient.InsertUnique(tableName, string(chain), 1, rule...); err != nil {
+				return fmt.Errorf("insert jump rule into %s: %w", chain, err)
+			}
+		}
+	}
+
+	for chain, entries := range r.optionalEntries {
+		for _, entry := range entries {
+			if err := r.iptablesClient.InsertUnique(tableName, string(chain), entry.position, entry.spec...); err != nil {
+				log.Errorf("failed to insert optional entry %v: %v", entry.spec, err)
+				continue
+			}
+			r.entries[chain] = append(r.entries[chain], entry.spec)
+		}
+	}
+	clear(r.optionalEntries)
+
+	// Insert mangle FORWARD guard rules to prevent external DNAT bypass.
+	for _, rule := range r.entries[mangleForwardKey] {
+		if err := r.iptablesClient.AppendUnique(tableMangle, chainForward, rule...); err != nil {
+			log.Errorf("failed to add mangle FORWARD guard rule: %v", err)
+		}
+	}
+
+	return nil
+}
+
+func (r *family) cleanUpDefaultForwardRules() error {
+	var merr *multierror.Error
+
+	// cleanJumpRules removes the OUTPUT jump to NETBIRD-NAT-OUTPUT among
+	// the others, so the chain below deletes cleanly instead of failing
+	// with "device or resource busy".
+	if err := r.cleanJumpRules(); err != nil {
+		merr = multierror.Append(merr, fmt.Errorf("clean jump rules: %w", err))
+	}
+
+	for _, chainInfo := range []struct {
+		chain string
+		table string
+	}{
+		{chainRTFwdIn, tableFilter},
+		{chainRTFwdOut, tableFilter},
+		{chainRTPre, tableMangle},
+		{chainRTNAT, tableNat},
+		{chainRTRdr, tableNat},
+		{chainNATOutput, tableNat},
+		{chainRTMSSClamp, tableMangle},
+	} {
+		ok, err := r.iptablesClient.ChainExists(chainInfo.table, chainInfo.chain)
+		if err != nil {
+			merr = multierror.Append(merr, fmt.Errorf("check chain %s in table %s: %w", chainInfo.chain, chainInfo.table, err))
+			continue
+		}
+		if ok {
+			if err := r.iptablesClient.ClearAndDeleteChain(chainInfo.table, chainInfo.chain); err != nil {
+				merr = multierror.Append(merr, fmt.Errorf("clear and delete chain %s in table %s: %w", chainInfo.chain, chainInfo.table, err))
+			}
+		}
+	}
+
+	return nberrors.FormatErrorOrNil(merr)
+}
+
+func (r *family) cleanJumpRules() error {
+	// locations maps each tracked jump rule to the built-in table and
+	// chain it was inserted into.
+	locations := map[firewall.RuleID]struct{ table, chain string }{
+		jumpNATPost:   {tableNat, chainPostrouting},
+		jumpManglePre: {tableMangle, chainPrerouting},
+		jumpNATPre:    {tableNat, chainPrerouting},
+		jumpMSSClamp:  {tableMangle, chainForward},
+		jumpNATOutput: {tableNat, chainOutput},
+	}
+
+	var merr *multierror.Error
+	for ruleID, loc := range locations {
+		rule, exists := r.rules[ruleID]
+		if !exists {
+			continue
+		}
+		if err := r.iptablesClient.DeleteIfExists(loc.table, loc.chain, rule...); err != nil {
+			merr = multierror.Append(merr, fmt.Errorf("delete rule from chain %s in table %s: %w", loc.chain, loc.table, err))
+			continue
+		}
+		delete(r.rules, ruleID)
+	}
+	return nberrors.FormatErrorOrNil(merr)
+}
+
+func (r *family) cleanAclChains() error {
+	var merr *multierror.Error
+
+	if err := r.cleanInputAclChain(); err != nil {
+		merr = multierror.Append(merr, err)
+	}
+
+	if err := r.cleanPreroutingEntries(); err != nil {
+		merr = multierror.Append(merr, err)
+	}
+
+	for _, rule := range r.entries[mangleForwardKey] {
+		if err := r.iptablesClient.DeleteIfExists(tableMangle, chainForward, rule...); err != nil {
+			merr = multierror.Append(merr, fmt.Errorf("delete mangle %s guard rule %v: %w", chainForward, rule, err))
+		}
+	}
+
+	return nberrors.FormatErrorOrNil(merr)
+}
+
+func (r *family) cleanInputAclChain() error {
+	ok, err := r.iptablesClient.ChainExists(tableName, chainACLInput)
+	if err != nil {
+		return fmt.Errorf("check chain %s: %w", chainACLInput, err)
+	}
+	if !ok {
+		return nil
+	}
+
+	var merr *multierror.Error
+	for _, rule := range r.entries[chainInput] {
+		if err := r.iptablesClient.DeleteIfExists(tableName, chainInput, rule...); err != nil {
+			merr = multierror.Append(merr, fmt.Errorf("delete %s rule %v: %w", chainInput, rule, err))
+		}
+	}
+
+	for _, rule := range r.entries[chainForward] {
+		if err := r.iptablesClient.DeleteIfExists(tableName, chainForward, rule...); err != nil {
+			merr = multierror.Append(merr, fmt.Errorf("delete %s rule %v: %w", chainForward, rule, err))
+		}
+	}
+
+	if err := r.iptablesClient.ClearAndDeleteChain(tableName, chainACLInput); err != nil {
+		merr = multierror.Append(merr, fmt.Errorf("clear and delete %s chain: %w", chainACLInput, err))
+	}
+
+	return nberrors.FormatErrorOrNil(merr)
+}
+
+func (r *family) cleanPreroutingEntries() error {
+	ok, err := r.iptablesClient.ChainExists(tableMangle, chainPrerouting)
+	if err != nil {
+		return fmt.Errorf("check chain %s in %s: %w", chainPrerouting, tableMangle, err)
+	}
+	if !ok {
+		return nil
+	}
+
+	var merr *multierror.Error
+	for _, rule := range r.entries[chainPrerouting] {
+		if err := r.iptablesClient.DeleteIfExists(tableMangle, chainPrerouting, rule...); err != nil {
+			merr = multierror.Append(merr, fmt.Errorf("delete %s rule %v: %w", chainPrerouting, rule, err))
+		}
+	}
+
+	return nberrors.FormatErrorOrNil(merr)
+}
+
+func (r *family) cleanupDataPlaneMark() error {
+	var merr *multierror.Error
+	if preRule, exists := r.rules[markManglePre]; exists {
+		if err := r.iptablesClient.DeleteIfExists(tableMangle, chainPrerouting, preRule...); err != nil {
+			merr = multierror.Append(merr, fmt.Errorf("remove mangle prerouting rule: %w", err))
+		} else {
+			delete(r.rules, markManglePre)
+		}
+	}
+
+	if postRule, exists := r.rules[markManglePost]; exists {
+		if err := r.iptablesClient.DeleteIfExists(tableMangle, chainPostrouting, postRule...); err != nil {
+			merr = multierror.Append(merr, fmt.Errorf("remove mangle postrouting rule: %w", err))
+		} else {
+			delete(r.rules, markManglePost)
+		}
+	}
+
+	return nberrors.FormatErrorOrNil(merr)
+}

client/firewall/iptables/dnat_linux.go

@@ -0,0 +1,285 @@
+//go:build !android
+
+package iptables
+
+import (
+	"fmt"
+	"net/netip"
+	"strconv"
+	"strings"
+
+	"github.com/hashicorp/go-multierror"
+	log "github.com/sirupsen/logrus"
+
+	nberrors "github.com/netbirdio/netbird/client/errors"
+	firewall "github.com/netbirdio/netbird/client/firewall/manager"
+)
+
+func (r *family) AddDNATRule(rule firewall.ForwardRule) (firewall.Rule, error) {
+	ruleID := rule.ID()
+	if _, exists := r.rules[ruleID+dnatSuffix]; exists {
+		return rule, nil
+	}
+
+	toDestination := rule.TranslatedAddress.String()
+	switch {
+	case len(rule.TranslatedPort.Values) == 0:
+		// no translated port, use original port
+	case len(rule.TranslatedPort.Values) == 1:
+		toDestination += fmt.Sprintf(":%d", rule.TranslatedPort.Values[0])
+	case rule.TranslatedPort.IsRange && len(rule.TranslatedPort.Values) == 2:
+		// need the "/originalport" suffix to avoid dnat port randomization
+		toDestination += fmt.Sprintf(":%d-%d/%d", rule.TranslatedPort.Values[0], rule.TranslatedPort.Values[1], rule.DestinationPort.Values[0])
+	default:
+		return nil, fmt.Errorf("invalid translated port: %v", rule.TranslatedPort)
+	}
+
+	proto := strings.ToLower(string(rule.Protocol))
+
+	rules := make(map[firewall.RuleID]ruleInfo, 3)
+
+	// DNAT rule
+	dnatRule := []string{
+		"!", "-i", r.wgIface.Name(),
+		"-p", proto,
+		"-j", "DNAT",
+		"--to-destination", toDestination,
+	}
+	dnatRule = append(dnatRule, applyPort("--dport", &rule.DestinationPort)...)
+	rules[ruleID+dnatSuffix] = ruleInfo{
+		table: tableNat,
+		chain: chainRTRdr,
+		rule:  dnatRule,
+	}
+
+	// SNAT rule
+	snatRule := []string{
+		"-o", r.wgIface.Name(),
+		"-p", proto,
+		"-d", rule.TranslatedAddress.String(),
+		"-j", "MASQUERADE",
+	}
+	snatRule = append(snatRule, applyPort("--dport", &rule.TranslatedPort)...)
+	rules[ruleID+snatSuffix] = ruleInfo{
+		table: tableNat,
+		chain: chainRTNAT,
+		rule:  snatRule,
+	}
+
+	// Forward filtering rule, if fwd policy is DROP
+	forwardRule := []string{
+		"-o", r.wgIface.Name(),
+		"-p", proto,
+		"-d", rule.TranslatedAddress.String(),
+		"-j", "ACCEPT",
+	}
+	forwardRule = append(forwardRule, applyPort("--dport", &rule.TranslatedPort)...)
+	rules[ruleID+fwdSuffix] = ruleInfo{
+		table: tableFilter,
+		chain: chainRTFwdOut,
+		rule:  forwardRule,
+	}
+
+	// Request forwarding once the rule is about to be installed, releasing
+	// it if installation fails so the refcount tracks the real rules.
+	if err := r.ipFwdState.RequestForwarding(); err != nil {
+		return nil, err
+	}
+
+	for key, ruleInfo := range rules {
+		if err := r.iptablesClient.Append(ruleInfo.table, ruleInfo.chain, ruleInfo.rule...); err != nil {
+			if rollbackErr := r.rollbackRules(rules); rollbackErr != nil {
+				log.Errorf("rollback failed: %v", rollbackErr)
+			}
+			r.releaseForwarding()
+			return nil, fmt.Errorf("add rule %s: %w", key, err)
+		}
+		r.rules[key] = ruleInfo.rule
+	}
+
+	r.updateState()
+	return rule, nil
+}
+
+func (r *family) rollbackRules(rules map[firewall.RuleID]ruleInfo) error {
+	var merr *multierror.Error
+	for key, ruleInfo := range rules {
+		if err := r.iptablesClient.DeleteIfExists(ruleInfo.table, ruleInfo.chain, ruleInfo.rule...); err != nil {
+			merr = multierror.Append(merr, fmt.Errorf("rollback rule %s: %w", key, err))
+			// On rollback error, add to rules map for next cleanup
+			r.rules[key] = ruleInfo.rule
+		}
+	}
+	if merr != nil {
+		r.updateState()
+	}
+	return nberrors.FormatErrorOrNil(merr)
+}
+
+func (r *family) DeleteDNATRule(rule firewall.Rule) error {
+	ruleID := rule.ID()
+
+	var merr *multierror.Error
+	var found bool
+	if dnatRule, exists := r.rules[ruleID+dnatSuffix]; exists {
+		found = true
+		if err := r.iptablesClient.Delete(tableNat, chainRTRdr, dnatRule...); err != nil {
+			merr = multierror.Append(merr, fmt.Errorf("delete DNAT rule: %w", err))
+		}
+		delete(r.rules, ruleID+dnatSuffix)
+	}
+
+	if snatRule, exists := r.rules[ruleID+snatSuffix]; exists {
+		found = true
+		if err := r.iptablesClient.Delete(tableNat, chainRTNAT, snatRule...); err != nil {
+			merr = multierror.Append(merr, fmt.Errorf("delete SNAT rule: %w", err))
+		}
+		delete(r.rules, ruleID+snatSuffix)
+	}
+
+	if fwdRule, exists := r.rules[ruleID+fwdSuffix]; exists {
+		found = true
+		if err := r.iptablesClient.Delete(tableFilter, chainRTFwdOut, fwdRule...); err != nil {
+			merr = multierror.Append(merr, fmt.Errorf("delete forward rule: %w", err))
+		}
+		delete(r.rules, ruleID+fwdSuffix)
+	}
+
+	r.updateState()
+
+	// Release once, only if the rule was present and removed.
+	if merr == nil && found {
+		r.releaseForwarding()
+	}
+
+	return nberrors.FormatErrorOrNil(merr)
+}
+
+// releaseForwarding drops one IP forwarding reference, logging any error.
+func (r *family) releaseForwarding() {
+	if err := r.ipFwdState.ReleaseForwarding(); err != nil {
+		log.Errorf("release IP forwarding: %v", err)
+	}
+}
+
+func (r *family) AddInboundDNAT(localAddr netip.Addr, protocol firewall.Protocol, originalPort, translatedPort uint16) error {
+	ruleID := firewall.RuleID(fmt.Sprintf("inbound-dnat-%s-%s-%d-%d", localAddr.String(), protocol, originalPort, translatedPort))
+
+	if _, exists := r.rules[ruleID]; exists {
+		return nil
+	}
+
+	dnatRule := []string{
+		"-i", r.wgIface.Name(),
+		"-p", strings.ToLower(protoForFamily(protocol, r.v6)),
+		"--dport", strconv.Itoa(int(originalPort)),
+		"-d", localAddr.String(),
+		"-m", "addrtype", "--dst-type", "LOCAL",
+		"-j", "DNAT",
+		"--to-destination", ":" + strconv.Itoa(int(translatedPort)),
+	}
+
+	info := ruleInfo{
+		table: tableNat,
+		chain: chainRTRdr,
+		rule:  dnatRule,
+	}
+
+	if err := r.iptablesClient.Append(info.table, info.chain, info.rule...); err != nil {
+		return fmt.Errorf("add inbound DNAT rule: %w", err)
+	}
+	r.rules[ruleID] = info.rule
+
+	r.updateState()
+	return nil
+}
+
+// RemoveInboundDNAT removes an inbound DNAT rule.
+func (r *family) RemoveInboundDNAT(localAddr netip.Addr, protocol firewall.Protocol, originalPort, translatedPort uint16) error {
+	ruleID := firewall.RuleID(fmt.Sprintf("inbound-dnat-%s-%s-%d-%d", localAddr.String(), protocol, originalPort, translatedPort))
+
+	if dnatRule, exists := r.rules[ruleID]; exists {
+		if err := r.iptablesClient.Delete(tableNat, chainRTRdr, dnatRule...); err != nil {
+			return fmt.Errorf("delete inbound DNAT rule: %w", err)
+		}
+		delete(r.rules, ruleID)
+	}
+
+	r.updateState()
+	return nil
+}
+
+// ensureNATOutputChain lazily creates the OUTPUT NAT chain and jump rule on first use.
+func (r *family) ensureNATOutputChain() error {
+	if _, exists := r.rules[jumpNATOutput]; exists {
+		return nil
+	}
+
+	chainExists, err := r.iptablesClient.ChainExists(tableNat, chainNATOutput)
+	if err != nil {
+		return fmt.Errorf("check chain %s: %w", chainNATOutput, err)
+	}
+	if !chainExists {
+		if err := r.iptablesClient.NewChain(tableNat, chainNATOutput); err != nil {
+			return fmt.Errorf("create chain %s: %w", chainNATOutput, err)
+		}
+	}
+
+	jumpRule := []string{"-j", chainNATOutput}
+	if err := r.iptablesClient.Insert(tableNat, chainOutput, 1, jumpRule...); err != nil {
+		if !chainExists {
+			if delErr := r.iptablesClient.ClearAndDeleteChain(tableNat, chainNATOutput); delErr != nil {
+				log.Warnf("failed to rollback chain %s: %v", chainNATOutput, delErr)
+			}
+		}
+		return fmt.Errorf("add OUTPUT jump rule: %w", err)
+	}
+	r.rules[jumpNATOutput] = jumpRule
+
+	r.updateState()
+	return nil
+}
+
+// AddOutputDNAT adds an OUTPUT chain DNAT rule for locally-generated traffic.
+func (r *family) AddOutputDNAT(localAddr netip.Addr, protocol firewall.Protocol, originalPort, translatedPort uint16) error {
+	ruleID := firewall.RuleID(fmt.Sprintf("output-dnat-%s-%s-%d-%d", localAddr.String(), protocol, originalPort, translatedPort))
+
+	if _, exists := r.rules[ruleID]; exists {
+		return nil
+	}
+
+	if err := r.ensureNATOutputChain(); err != nil {
+		return err
+	}
+
+	dnatRule := []string{
+		"-p", strings.ToLower(protoForFamily(protocol, localAddr.Is6())),
+		"--dport", strconv.Itoa(int(originalPort)),
+		"-d", localAddr.String(),
+		"-j", "DNAT",
+		"--to-destination", ":" + strconv.Itoa(int(translatedPort)),
+	}
+
+	if err := r.iptablesClient.Append(tableNat, chainNATOutput, dnatRule...); err != nil {
+		return fmt.Errorf("add output DNAT rule: %w", err)
+	}
+	r.rules[ruleID] = dnatRule
+
+	r.updateState()
+	return nil
+}
+
+// RemoveOutputDNAT removes an OUTPUT chain DNAT rule.
+func (r *family) RemoveOutputDNAT(localAddr netip.Addr, protocol firewall.Protocol, originalPort, translatedPort uint16) error {
+	ruleID := firewall.RuleID(fmt.Sprintf("output-dnat-%s-%s-%d-%d", localAddr.String(), protocol, originalPort, translatedPort))
+
+	if dnatRule, exists := r.rules[ruleID]; exists {
+		if err := r.iptablesClient.Delete(tableNat, chainNATOutput, dnatRule...); err != nil {
+			return fmt.Errorf("delete output DNAT rule: %w", err)
+		}
+		delete(r.rules, ruleID)
+	}
+
+	r.updateState()
+	return nil
+}

client/firewall/iptables/family_linux.go

@@ -0,0 +1,246 @@
+//go:build !android
+
+package iptables
+
+import (
+	"fmt"
+	"net/netip"
+
+	"github.com/coreos/go-iptables/iptables"
+	"github.com/hashicorp/go-multierror"
+	log "github.com/sirupsen/logrus"
+
+	nberrors "github.com/netbirdio/netbird/client/errors"
+	firewall "github.com/netbirdio/netbird/client/firewall/manager"
+	nbid "github.com/netbirdio/netbird/client/internal/acl/id"
+	"github.com/netbirdio/netbird/client/internal/routemanager/ipfwdstate"
+	"github.com/netbirdio/netbird/client/internal/routemanager/refcounter"
+	"github.com/netbirdio/netbird/client/internal/statemanager"
+)
+
+// constants needed to manage and create iptable rules
+const (
+	tableFilter = "filter"
+	tableName   = tableFilter
+	tableNat    = "nat"
+	tableMangle = "mangle"
+
+	// chainACLInput is the peer ACL chain that holds installed
+	// peer-filtering rules.
+	chainACLInput = "NETBIRD-ACL-INPUT"
+
+	// mangleForwardKey is the entries map key for mangle FORWARD guard
+	// rules that prevent external DNAT from bypassing ACL rules.
+	mangleForwardKey chainKey = "MANGLE-FORWARD"
+
+	chainInput              = "INPUT"
+	chainPostrouting        = "POSTROUTING"
+	chainPrerouting         = "PREROUTING"
+	chainForward            = "FORWARD"
+	chainRTNAT              = "NETBIRD-RT-NAT"
+	chainRTFwdIn            = "NETBIRD-RT-FWD-IN"
+	chainRTFwdOut           = "NETBIRD-RT-FWD-OUT"
+	chainRTPre              = "NETBIRD-RT-PRE"
+	chainRTRdr              = "NETBIRD-RT-RDR"
+	chainNATOutput          = "NETBIRD-NAT-OUTPUT"
+	chainRTMSSClamp         = "NETBIRD-RT-MSSCLAMP"
+
+	jumpManglePre  = "jump-mangle-pre"
+	jumpNATPre     = "jump-nat-pre"
+	jumpNATPost    = "jump-nat-post"
+	jumpNATOutput  = "jump-nat-output"
+	jumpMSSClamp   = "jump-mss-clamp"
+	markManglePre  = "mark-mangle-pre"
+	markManglePost = "mark-mangle-post"
+	matchSet       = "--match-set"
+
+	dnatSuffix firewall.RuleID = "_dnat"
+	snatSuffix firewall.RuleID = "_snat"
+	fwdSuffix  firewall.RuleID = "_fwd"
+
+	// ipv4TCPHeaderSize is the minimum IPv4 (20) + TCP (20) header size for MSS calculation.
+	ipv4TCPHeaderSize = 40
+	// ipv6TCPHeaderSize is the minimum IPv6 (40) + TCP (20) header size for MSS calculation.
+	ipv6TCPHeaderSize = 60
+)
+
+type ruleInfo struct {
+	chain string
+	table string
+	rule  []string
+}
+
+type routeRules map[firewall.RuleID][]string
+
+// ruleSpec is a single iptables rule expressed as its argument list
+// (e.g. {"-i", "wg0", "-j", "DROP"}).
+type ruleSpec []string
+
+// chainKey identifies the chain a seeded entry belongs to. It holds
+// built-in chain names ("INPUT", "FORWARD", "PREROUTING") plus the
+// synthetic mangleForwardKey bucket for the mangle FORWARD guard rules.
+type chainKey string
+
+// aclEntries maps a chain to the rules seeded into it to jump into or
+// guard the netbird ACL chains.
+type aclEntries map[chainKey][]ruleSpec
+
+type entry struct {
+	spec     ruleSpec
+	position int
+}
+
+// ipsetCounter is the shared hash:net refcounter used by peer and
+// route ACLs alike. The ipset library does not support comments, so
+// the key is just the set name (string).
+type ipsetCounter = refcounter.Counter[string, []netip.Prefix, struct{}]
+
+// family holds the per-address-family iptables state. One instance
+// handles route ACLs, peer ACLs, NAT, DNAT, and MSS clamping for a
+// single family; the top-level Manager owns one for v4 and another
+// for v6.
+type family struct {
+	iptablesClient *iptables.IPTables
+	wgIface        iFaceMapper
+	v6             bool
+
+	// Peer ACL chain bookkeeping.
+	entries         aclEntries
+	optionalEntries map[chainKey][]entry
+
+	// filters holds peer + route filter rules keyed by content hash.
+	// AddFilterRule writes here; DeleteFilterRule looks up by id.
+	filters      map[nbid.RuleID]*Rule
+	ipsetCounter *ipsetCounter
+
+	// rules holds NAT, jump, and MSS-clamping rules (auxiliary
+	// plumbing that isn't a filter rule).
+	rules routeRules
+
+	// Routing / NAT.
+	legacyManagement bool
+	mtu              uint16
+	ipFwdState       *ipfwdstate.IPForwardingState
+
+	stateManager *statemanager.Manager
+}
+
+func newFamily(iptablesClient *iptables.IPTables, wgIface iFaceMapper, mtu uint16) (*family, error) {
+	r := &family{
+		iptablesClient:  iptablesClient,
+		wgIface:         wgIface,
+		v6:              iptablesClient.Proto() == iptables.ProtocolIPv6,
+		entries:         make(aclEntries),
+		optionalEntries: make(map[chainKey][]entry),
+		filters:         make(map[nbid.RuleID]*Rule),
+		rules:           make(routeRules),
+		mtu:             mtu,
+		ipFwdState:      ipfwdstate.NewIPForwardingState(),
+	}
+
+	r.ipsetCounter = refcounter.New(
+		func(name string, sources []netip.Prefix) (struct{}, error) {
+			return struct{}{}, r.createIpSet(name, sources)
+		},
+		func(name string, _ struct{}) error {
+			return r.deleteIpSet(name)
+		},
+	)
+
+	return r, nil
+}
+
+// init wires the family to the state manager and installs both the
+// route ACL containers and the peer ACL chain skeleton.
+func (r *family) init(stateManager *statemanager.Manager) error {
+	r.stateManager = stateManager
+
+	if err := r.cleanUpDefaultForwardRules(); err != nil {
+		log.Errorf("failed to clean up rules from FORWARD chain: %s", err)
+	}
+
+	if err := r.createContainers(); err != nil {
+		return fmt.Errorf("create containers: %w", err)
+	}
+
+	if err := r.setupDataPlaneMark(); err != nil {
+		log.Errorf("failed to set up data plane mark: %v", err)
+	}
+
+	r.seedInitialEntries()
+	r.seedInitialOptionalEntries()
+
+	if err := r.cleanAclChains(); err != nil {
+		return fmt.Errorf("clean acl chains: %w", err)
+	}
+	if err := r.createDefaultChains(); err != nil {
+		return fmt.Errorf("create default chains: %w", err)
+	}
+
+	r.updateState()
+
+	return nil
+}
+
+// Reset tears down all firewall state owned by this family. ACL
+// chain cleanup runs before route-chain cleanup because the route
+// chains are still referenced by FORWARD jumps installed during
+// seedInitialEntries; deleting them first would trip EBUSY.
+func (r *family) Reset() error {
+	var merr *multierror.Error
+
+	if err := r.cleanAclChains(); err != nil {
+		merr = multierror.Append(merr, err)
+	}
+
+	if err := r.cleanUpDefaultForwardRules(); err != nil {
+		merr = multierror.Append(merr, err)
+	}
+
+	if err := r.ipsetCounter.Flush(); err != nil {
+		merr = multierror.Append(merr, err)
+	}
+
+	if err := r.cleanupDataPlaneMark(); err != nil {
+		merr = multierror.Append(merr, err)
+	}
+
+	clear(r.rules)
+	clear(r.filters)
+	r.updateState()
+
+	return nberrors.FormatErrorOrNil(merr)
+}
+
+func (r *family) updateState() {
+	if r.stateManager == nil {
+		return
+	}
+
+	var currentState *ShutdownState
+	if existing := r.stateManager.GetState(currentState); existing != nil {
+		if existingState, ok := existing.(*ShutdownState); ok {
+			currentState = existingState
+		}
+	}
+	if currentState == nil {
+		currentState = &ShutdownState{}
+	}
+
+	currentState.Lock()
+	defer currentState.Unlock()
+
+	if r.v6 {
+		currentState.RouteRules6 = r.rules
+		currentState.RouteIPsetCounter6 = r.ipsetCounter
+		currentState.ACLEntries6 = r.entries
+	} else {
+		currentState.RouteRules = r.rules
+		currentState.RouteIPsetCounter = r.ipsetCounter
+		currentState.ACLEntries = r.entries
+	}
+
+	if err := r.stateManager.UpdateState(currentState); err != nil {
+		log.Errorf("failed to update state: %v", err)
+	}
+}

client/firewall/iptables/filter_linux.go

@@ -0,0 +1,341 @@
+//go:build !android
+
+package iptables
+
+import (
+	"fmt"
+	"net/netip"
+	"slices"
+	"strconv"
+	"strings"
+
+	"github.com/hashicorp/go-multierror"
+	log "github.com/sirupsen/logrus"
+
+	nberrors "github.com/netbirdio/netbird/client/errors"
+	firewall "github.com/netbirdio/netbird/client/firewall/manager"
+	nbid "github.com/netbirdio/netbird/client/internal/acl/id"
+	nbnet "github.com/netbirdio/netbird/client/net"
+)
+
+// AddFilterRule installs a packet-filtering rule. With destination
+// empty, the rule goes to the peer ACL input chain plus a paired
+// mangle PREROUTING rule for the redirect mark. With destination set
+// (prefix or named set), it goes to the route ACL forward chain.
+// Multi-source rules collapse to one iptables rule via the shared
+// hash:net ipset.
+func (r *family) AddFilterRule(
+	id []byte,
+	sources []netip.Prefix,
+	destination firewall.Network,
+	proto firewall.Protocol,
+	sPort *firewall.Port,
+	dPort *firewall.Port,
+	action firewall.Action,
+) (firewall.Rule, error) {
+	ruleID := nbid.GenerateRuleID(sources, destination, proto, sPort, dPort, action)
+	if existing, ok := r.filters[ruleID]; ok {
+		return existing, nil
+	}
+
+	srcMatch, err := r.applySourceMatch(sourceNetwork(sources), sources)
+	if err != nil {
+		return nil, fmt.Errorf("apply source match: %w", err)
+	}
+
+	rule, err := r.installFilterRule(ruleID, srcMatch, destination, proto, sPort, dPort, action)
+	if err != nil {
+		r.dropSourceMatch(srcMatch)
+		return nil, err
+	}
+
+	r.filters[ruleID] = rule
+	r.updateState()
+	return rule, nil
+}
+
+func (r *family) hasRule(id nbid.RuleID) bool {
+	_, ok := r.filters[id]
+	return ok
+}
+
+// hasDNATRule reports whether this family owns the DNAT rule set for
+// the given user id. DNAT rules live in r.rules under the well-known
+// "<id>_dnat" key; the lookup here is used by Manager.DeleteDNATRule
+// to pick the right family.
+func (r *family) hasDNATRule(id firewall.RuleID) bool {
+	_, ok := r.rules[id+dnatSuffix]
+	return ok
+}
+
+// DeleteFilterRule removes a previously installed filter rule. The
+// rule's stored chain/table identify where to delete from; source set
+// references are recovered from the spec via findSets and dropped
+// from the shared ipset counter.
+func (r *family) DeleteFilterRule(rule firewall.Rule) error {
+	ruleID := rule.ID()
+	pr, ok := r.filters[ruleID]
+	if !ok {
+		log.Debugf("filter rule %s not found", ruleID)
+		return nil
+	}
+
+	// DeleteIfExists keeps both deletes idempotent so a retry after a
+	// partial failure does not error on the half that was already removed.
+	var merr *multierror.Error
+	if err := r.iptablesClient.DeleteIfExists(tableFilter, pr.chain, pr.specs...); err != nil {
+		merr = multierror.Append(merr, fmt.Errorf("delete rule from %s: %w", pr.chain, err))
+	}
+	if pr.mangleSpecs != nil {
+		if err := r.iptablesClient.DeleteIfExists(tableMangle, chainRTPre, pr.mangleSpecs...); err != nil {
+			merr = multierror.Append(merr, fmt.Errorf("delete mangle rule: %w", err))
+		}
+	}
+	if merr != nil {
+		// Leave the rule tracked so the caller retries the remaining half.
+		return nberrors.FormatErrorOrNil(merr)
+	}
+
+	r.dropSourceMatch(pr.specs)
+	delete(r.filters, ruleID)
+	r.updateState()
+	return nil
+}
+
+// findSets scans an iptables rule spec for "-m set --match-set <name>
+// <dir>" fragments and returns the named sets in occurrence order.
+// Used at delete time to drop ipsetCounter references.
+func findSets(rule []string) []string {
+	var sets []string
+	for i, arg := range rule {
+		if arg == "-m" && i+3 < len(rule) && rule[i+1] == "set" && rule[i+2] == matchSet {
+			sets = append(sets, rule[i+3])
+		}
+	}
+	return sets
+}
+
+// sourceNetwork classifies a source-prefix list into the firewall.Network
+// shape the rest of the spec-builder consumes: empty for match-any, a
+// single prefix inline, or an ipset for multiple sources.
+func sourceNetwork(sources []netip.Prefix) firewall.Network {
+	switch {
+	case len(sources) == 0:
+		return firewall.Network{}
+	case len(sources) == 1 && sources[0].Bits() == 0:
+		return firewall.Network{}
+	case len(sources) == 1:
+		return firewall.Network{Prefix: sources[0]}
+	default:
+		return firewall.Network{Set: firewall.NewPrefixSet(sources)}
+	}
+}
+
+// applySourceMatch returns the iptables match fragment for the rule's
+// source. For a Set it increments the shared ipset's refcount; for a
+// Prefix it emits a direct -s match; for the wildcard it returns nil.
+func (r *family) applySourceMatch(network firewall.Network, prefixes []netip.Prefix) ([]string, error) {
+	switch {
+	case network.IsSet():
+		if r.ipsetCounter == nil {
+			return nil, fmt.Errorf("multi-source peer rule requires shared ipset counter")
+		}
+		name := r.ipsetName(network.Set.HashedName())
+		if _, err := r.ipsetCounter.Increment(name, prefixes); err != nil {
+			return nil, fmt.Errorf("ipset increment %s: %w", name, err)
+		}
+		return []string{"-m", "set", matchSet, name, "src"}, nil
+	case network.IsPrefix():
+		return []string{"-s", network.Prefix.String()}, nil
+	default:
+		return nil, nil
+	}
+}
+
+// dropSourceMatch undoes whatever applySourceMatch reserved. Safe to
+// call when the spec is empty or holds only inline matchers. Decrement
+// errors are logged but not returned: the filter rule has already been
+// deleted at that point and we don't want to leak the deletion.
+func (r *family) dropSourceMatch(srcMatch []string) {
+	if r.ipsetCounter == nil {
+		return
+	}
+	for _, name := range findSets(srcMatch) {
+		if _, err := r.ipsetCounter.Decrement(name); err != nil {
+			log.Errorf("rollback ipset decrement %s: %v", name, err)
+		}
+	}
+}
+
+// decrementSetCounter drops ipset references owned by a raw rule spec
+// stored in r.rules (NAT / legacy route entries). It returns an error
+// aggregate so the caller surfaces decrement failures.
+func (r *family) decrementSetCounter(rule []string) error {
+	if r.ipsetCounter == nil {
+		return nil
+	}
+	var merr *multierror.Error
+	for _, name := range findSets(rule) {
+		if _, err := r.ipsetCounter.Decrement(name); err != nil {
+			merr = multierror.Append(merr, fmt.Errorf("decrement counter: %w", err))
+		}
+	}
+	return nberrors.FormatErrorOrNil(merr)
+}
+
+// installFilterRule assembles and writes one iptables filter-chain
+// rule. With destination empty the rule lands in the peer ACL input
+// chain and a paired mangle PREROUTING rule is added for the redirect
+// mark. With destination set the rule lands in the route ACL forward
+// chain and there is no mangle pairing.
+func (r *family) installFilterRule(
+	ruleID nbid.RuleID,
+	srcMatch []string,
+	destination firewall.Network,
+	protocol firewall.Protocol,
+	sPort, dPort *firewall.Port,
+	action firewall.Action,
+) (*Rule, error) {
+	isRoute := !destination.IsZero()
+
+	proto := protoForFamily(protocol, r.v6)
+
+	specs := slices.Clone(srcMatch)
+	var destExp []string
+	if isRoute {
+		var err error
+		destExp, err = r.applyNetwork("-d", destination, nil)
+		if err != nil {
+			return nil, fmt.Errorf("apply network -d: %w", err)
+		}
+		specs = append(specs, destExp...)
+	}
+	specs = append(specs, filterMatchSpecs(proto, sPort, dPort)...)
+
+	var mangleSpecs []string
+	if !isRoute {
+		mangleSpecs = slices.Clone(specs)
+		mangleSpecs = append(mangleSpecs,
+			"-i", r.wgIface.Name(),
+			"-m", "addrtype", "--dst-type", "LOCAL",
+			"-j", "MARK", "--set-xmark", fmt.Sprintf("%#x", nbnet.PreroutingFwmarkRedirected),
+		)
+	}
+
+	specs = append(specs, "-j", actionToStr(action))
+
+	chain := chainACLInput
+	if isRoute {
+		chain = chainRTFwdIn
+	}
+
+	// Peer ACL drops are inserted at position 1 so they precede the
+	// chain's catch-all; route ACL drops are inserted at position 2
+	// to sit immediately after the established/related accept rule.
+	var err error
+	if action == firewall.ActionDrop {
+		pos := 1
+		if isRoute {
+			pos = 2
+		}
+		err = r.iptablesClient.Insert(tableFilter, chain, pos, specs...)
+	} else {
+		err = r.iptablesClient.Append(tableFilter, chain, specs...)
+	}
+	if err != nil {
+		r.dropSourceMatch(destExp)
+		return nil, fmt.Errorf("install filter rule on %s: %w", chain, err)
+	}
+
+	// The mangle redirect-mark rule is best effort: the filter rule itself
+	// is what enforces the ACL, so a mangle failure must not undo it. Drop
+	// the spec so teardown does not try to remove a rule that was not added.
+	if mangleSpecs != nil {
+		if err := r.iptablesClient.Append(tableMangle, chainRTPre, mangleSpecs...); err != nil {
+			log.Errorf("add mangle rule: %v", err)
+			mangleSpecs = nil
+		}
+	}
+
+	return &Rule{
+		id:          ruleID,
+		specs:       specs,
+		mangleSpecs: mangleSpecs,
+		chain:       chain,
+		v6:          r.v6,
+	}, nil
+}
+
+// applyNetwork resolves a firewall.Network into the iptables match
+// fragment for the given direction flag (-s or -d). Set networks
+// increment the shared ipset refcount; prefixes emit a direct match;
+// an empty network returns no spec ("match any").
+func (r *family) applyNetwork(flag string, network firewall.Network, prefixes []netip.Prefix) ([]string, error) {
+	direction := "src"
+	if flag == "-d" {
+		direction = "dst"
+	}
+
+	if network.IsSet() {
+		name := r.ipsetName(network.Set.HashedName())
+		if _, err := r.ipsetCounter.Increment(name, prefixes); err != nil {
+			return nil, fmt.Errorf("create or get ipset: %w", err)
+		}
+
+		return []string{"-m", "set", matchSet, name, direction}, nil
+	}
+	if network.IsPrefix() {
+		return []string{flag, network.Prefix.String()}, nil
+	}
+
+	// nolint:nilnil
+	return nil, nil
+}
+
+// protoForFamily translates ICMP to ICMPv6 for ip6tables.
+// ip6tables requires "ipv6-icmp" (or "icmpv6") instead of "icmp".
+func protoForFamily(protocol firewall.Protocol, v6 bool) string {
+	if v6 && protocol == firewall.ProtocolICMP {
+		return "ipv6-icmp"
+	}
+	return string(protocol)
+}
+
+// filterMatchSpecs returns the proto/port match fragment for a
+// filtering rule. The source match (-s or -m set) is built by the
+// caller and prepended.
+func filterMatchSpecs(protocol string, sPort, dPort *firewall.Port) (specs []string) {
+	if protocol != "all" {
+		specs = append(specs, "-p", protocol)
+	}
+	specs = append(specs, applyPort("--sport", sPort)...)
+	specs = append(specs, applyPort("--dport", dPort)...)
+	return specs
+}
+
+func actionToStr(action firewall.Action) string {
+	if action == firewall.ActionAccept {
+		return "ACCEPT"
+	}
+	return "DROP"
+}
+
+func applyPort(flag string, port *firewall.Port) []string {
+	if port == nil {
+		return nil
+	}
+
+	if port.IsRange && len(port.Values) == 2 {
+		return []string{flag, fmt.Sprintf("%d:%d", port.Values[0], port.Values[1])}
+	}
+
+	if len(port.Values) > 1 {
+		portList := make([]string, len(port.Values))
+		for i, p := range port.Values {
+			portList[i] = strconv.Itoa(int(p))
+		}
+		return []string{"-m", "multiport", flag, strings.Join(portList, ",")}
+	}
+
+	return []string{flag, strconv.Itoa(int(port.Values[0]))}
+}

client/firewall/iptables/ipset_linux.go

@@ -0,0 +1,104 @@
+//go:build !android
+
+package iptables
+
+import (
+	"fmt"
+	"net/netip"
+
+	"github.com/hashicorp/go-multierror"
+	"github.com/lrh3321/ipset-go"
+	log "github.com/sirupsen/logrus"
+
+	nberrors "github.com/netbirdio/netbird/client/errors"
+	firewall "github.com/netbirdio/netbird/client/firewall/manager"
+)
+
+func (r *family) createIpSet(setName string, sources []netip.Prefix) error {
+	if err := r.createIPSet(setName); err != nil {
+		return fmt.Errorf("create set %s: %w", setName, err)
+	}
+
+	for _, prefix := range sources {
+		if err := r.addPrefixToIPSet(setName, prefix); err != nil {
+			// The refcounter records nothing when this callback errors,
+			// so destroy the set or it leaks in the kernel. A partial
+			// source set would also fail-open for deny rules, so the
+			// rule must fail rather than install with a missing source.
+			if derr := r.destroyIPSet(setName); derr != nil {
+				log.Warnf("rollback ipset %s after add failure: %v", setName, derr)
+			}
+			return fmt.Errorf("add element to set %s: %w", setName, err)
+		}
+	}
+
+	return nil
+}
+
+func (r *family) deleteIpSet(setName string) error {
+	if err := r.destroyIPSet(setName); err != nil {
+		return fmt.Errorf("destroy set %s: %w", setName, err)
+	}
+
+	log.Debugf("deleted unused ipset %s", setName)
+	return nil
+}
+
+func (r *family) UpdateSet(set firewall.Set, prefixes []netip.Prefix) error {
+	name := r.ipsetName(set.HashedName())
+	var merr *multierror.Error
+	for _, prefix := range prefixes {
+		if err := r.addPrefixToIPSet(name, prefix); err != nil {
+			merr = multierror.Append(merr, fmt.Errorf("add prefix to ipset: %w", err))
+		}
+	}
+	if merr == nil {
+		log.Debugf("updated set %s with prefixes %v", name, prefixes)
+	}
+
+	return nberrors.FormatErrorOrNil(merr)
+}
+
+func (r *family) ipsetName(name string) string {
+	if r.v6 {
+		return name + "-v6"
+	}
+	return name
+}
+
+func (r *family) createIPSet(name string) error {
+	opts := ipset.CreateOptions{
+		Replace: true,
+	}
+	if r.v6 {
+		opts.Family = ipset.FamilyIPV6
+	}
+
+	if err := ipset.Create(name, ipset.TypeHashNet, opts); err != nil {
+		return fmt.Errorf("create ipset %s: %w", name, err)
+	}
+
+	log.Debugf("created ipset %s with type hash:net", name)
+	return nil
+}
+
+func (r *family) addPrefixToIPSet(name string, prefix netip.Prefix) error {
+	addr := prefix.Addr()
+	ip := addr.AsSlice()
+
+	entry := &ipset.Entry{
+		IP:      ip,
+		CIDR:    uint8(prefix.Bits()),
+		Replace: true,
+	}
+
+	if err := ipset.Add(name, entry); err != nil {
+		return fmt.Errorf("add prefix to ipset %s: %w", name, err)
+	}
+
+	return nil
+}
+
+func (r *family) destroyIPSet(name string) error {
+	return ipset.Destroy(name)
+}

client/firewall/iptables/manager_linux.go

@@ -3,7 +3,6 @@ package iptables
 import (
 	"context"
 	"fmt"
-	"net"
 	"net/netip"
 	"sync"
 
@@ -18,25 +17,21 @@ import (
 	"github.com/netbirdio/netbird/client/internal/statemanager"
 )
 
-type resetter interface {
-	Reset() error
-}
-
-// Manager of iptables firewall
+// Manager of iptables firewall. Per-family state (peer ACLs, route
+// ACLs, NAT, DNAT, MSS clamping) lives on family; Manager dispatches
+// by family and provides the public firewall.Manager surface.
 type Manager struct {
 	mutex sync.Mutex
 
 	wgIface iFaceMapper
 
 	ipv4Client   *iptables.IPTables
-	aclMgr       *aclManager
-	router       *router
+	family4      *family
 	rawSupported bool
 
 	// IPv6 counterparts, nil when no v6 overlay
 	ipv6Client *iptables.IPTables
-	aclMgr6    *aclManager
-	router6    *router
+	family6    *family
 }
 
 // iFaceMapper defines subset methods of interface required for manager
@@ -57,14 +52,9 @@ func Create(wgIface iFaceMapper, mtu uint16) (*Manager, error) {
 		ipv4Client: iptablesClient,
 	}
 
-	m.router, err = newRouter(iptablesClient, wgIface, mtu)
+	m.family4, err = newFamily(iptablesClient, wgIface, mtu)
 	if err != nil {
-		return nil, fmt.Errorf("create router: %w", err)
-	}
-
-	m.aclMgr, err = newAclManager(iptablesClient, wgIface)
-	if err != nil {
-		return nil, fmt.Errorf("create acl manager: %w", err)
+		return nil, fmt.Errorf("create family: %w", err)
 	}
 
 	if wgIface.Address().HasIPv6() {
@@ -81,21 +71,18 @@ func (m *Manager) createIPv6Components(wgIface iFaceMapper, mtu uint16) error {
 	if err != nil {
 		return fmt.Errorf("init ip6tables: %w", err)
 	}
-	m.ipv6Client = ip6Client
 
-	m.router6, err = newRouter(ip6Client, wgIface, mtu)
+	family6, err := newFamily(ip6Client, wgIface, mtu)
 	if err != nil {
-		return fmt.Errorf("create v6 router: %w", err)
+		return fmt.Errorf("create v6 family: %w", err)
 	}
 
-	// Share the same IP forwarding state with the v4 router, since
+	// Share the same IP forwarding state with the v4 family, since
 	// EnableIPForwarding controls both v4 and v6 sysctls.
-	m.router6.ipFwdState = m.router.ipFwdState
+	family6.ipFwdState = m.family4.ipFwdState
 
-	m.aclMgr6, err = newAclManager(ip6Client, wgIface)
-	if err != nil {
-		return fmt.Errorf("create v6 acl manager: %w", err)
-	}
+	m.ipv6Client = ip6Client
+	m.family6 = family6
 
 	return nil
 }
@@ -109,7 +96,7 @@ func (m *Manager) Init(stateManager *statemanager.Manager) error {
 		InterfaceState: &InterfaceState{
 			NameStr:   m.wgIface.Name(),
 			WGAddress: m.wgIface.Address(),
-			MTU:       m.router.mtu,
+			MTU:       m.family4.mtu,
 		},
 	}
 	stateManager.RegisterState(state)
@@ -141,31 +128,24 @@ func (m *Manager) Init(stateManager *statemanager.Manager) error {
 	return nil
 }
 
-// initChains initializes router and ACL chains for both address families,
-// rolling back on failure.
+// initChains initializes the per-family firewall state for both
+// address families, rolling back on failure.
 func (m *Manager) initChains(stateManager *statemanager.Manager) error {
 	type initStep struct {
 		name string
-		init func(*statemanager.Manager) error
-		mgr  resetter
+		r    *family
 	}
 
-	steps := []initStep{
-		{"router", m.router.init, m.router},
-		{"acl manager", m.aclMgr.init, m.aclMgr},
-	}
+	steps := []initStep{{"v4", m.family4}}
 	if m.hasIPv6() {
-		steps = append(steps,
-			initStep{"v6 router", m.router6.init, m.router6},
-			initStep{"v6 acl manager", m.aclMgr6.init, m.aclMgr6},
-		)
+		steps = append(steps, initStep{"v6", m.family6})
 	}
 
 	var initialized []initStep
 	for _, s := range steps {
-		if err := s.init(stateManager); err != nil {
+		if err := s.r.init(stateManager); err != nil {
 			for i := len(initialized) - 1; i >= 0; i-- {
-				if rerr := initialized[i].mgr.Reset(); rerr != nil {
+				if rerr := initialized[i].r.Reset(); rerr != nil {
 					log.Warnf("rollback %s: %v", initialized[i].name, rerr)
 				}
 			}
@@ -176,84 +156,50 @@ func (m *Manager) initChains(stateManager *statemanager.Manager) error {
 	return nil
 }
 
-// AddPeerFiltering adds a rule to the firewall
-//
-// Comment will be ignored because some system this feature is not supported
-func (m *Manager) AddPeerFiltering(
-	id []byte,
-	ip net.IP,
-	proto firewall.Protocol,
-	sPort *firewall.Port,
-	dPort *firewall.Port,
-	action firewall.Action,
-	ipsetName string,
-) ([]firewall.Rule, error) {
-	m.mutex.Lock()
-	defer m.mutex.Unlock()
-
-	if ip.To4() != nil {
-		return m.aclMgr.AddPeerFiltering(id, ip, proto, sPort, dPort, action, ipsetName)
-	}
-	if !m.hasIPv6() {
-		return nil, fmt.Errorf("add peer filtering for %s: %w", ip, firewall.ErrIPv6NotInitialized)
-	}
-	return m.aclMgr6.AddPeerFiltering(id, ip, proto, sPort, dPort, action, ipsetName)
-}
-
-func (m *Manager) AddRouteFiltering(
+// AddFilterRule installs a packet-filtering rule. See firewall.Manager
+// docs for destination semantics. Sources are a single address family;
+// the rule is dispatched to the matching v4 / v6 backend.
+func (m *Manager) AddFilterRule(
 	id []byte,
 	sources []netip.Prefix,
 	destination firewall.Network,
 	proto firewall.Protocol,
-	sPort, dPort *firewall.Port,
+	sPort *firewall.Port,
+	dPort *firewall.Port,
 	action firewall.Action,
 ) (firewall.Rule, error) {
+	if len(sources) == 0 {
+		return nil, firewall.ErrNoSources
+	}
+
 	m.mutex.Lock()
 	defer m.mutex.Unlock()
 
-	if isIPv6RouteRule(sources, destination) {
+	fam := m.family4
+	if isIPv6Rule(sources, destination) {
 		if !m.hasIPv6() {
-			return nil, fmt.Errorf("add route filtering: %w", firewall.ErrIPv6NotInitialized)
+			return nil, fmt.Errorf("add filtering: %w", firewall.ErrIPv6NotInitialized)
 		}
-		return m.router6.AddRouteFiltering(id, sources, destination, proto, sPort, dPort, action)
+		fam = m.family6
 	}
-
-	return m.router.AddRouteFiltering(id, sources, destination, proto, sPort, dPort, action)
+	return fam.AddFilterRule(id, sources, destination, proto, sPort, dPort, action)
 }
 
-func isIPv6RouteRule(sources []netip.Prefix, destination firewall.Network) bool {
-	if destination.IsPrefix() {
-		return destination.Prefix.Addr().Is6()
-	}
-	return len(sources) > 0 && sources[0].Addr().Is6()
-}
-
-// DeletePeerRule from the firewall by rule definition
-func (m *Manager) DeletePeerRule(rule firewall.Rule) error {
+// DeleteFilterRule removes a rule previously added via AddFilterRule.
+// The rule is looked up by id in each family's filter cache.
+func (m *Manager) DeleteFilterRule(rule firewall.Rule) error {
 	m.mutex.Lock()
 	defer m.mutex.Unlock()
 
-	if m.hasIPv6() && isIPv6IptRule(rule) {
-		return m.aclMgr6.DeletePeerRule(rule)
+	id := rule.ID()
+	if m.family4.hasRule(id) {
+		return m.family4.DeleteFilterRule(rule)
 	}
-	return m.aclMgr.DeletePeerRule(rule)
-}
-
-func isIPv6IptRule(rule firewall.Rule) bool {
-	r, ok := rule.(*Rule)
-	return ok && r.v6
-}
-
-// DeleteRouteRule deletes a routing rule.
-// Route rules are keyed by content hash. Check v4 first, try v6 if not found.
-func (m *Manager) DeleteRouteRule(rule firewall.Rule) error {
-	m.mutex.Lock()
-	defer m.mutex.Unlock()
-
-	if m.hasIPv6() && !m.router.hasRule(rule.ID()) {
-		return m.router6.DeleteRouteRule(rule)
+	if m.hasIPv6() && m.family6.hasRule(id) {
+		return m.family6.DeleteFilterRule(rule)
 	}
-	return m.router.DeleteRouteRule(rule)
+	log.Debugf("filter rule %s not found in any family", id)
+	return nil
 }
 
 func (m *Manager) IsServerRouteSupported() bool {
@@ -272,10 +218,10 @@ func (m *Manager) AddNatRule(pair firewall.RouterPair) error {
 		if !m.hasIPv6() {
 			return fmt.Errorf("add NAT rule: %w", firewall.ErrIPv6NotInitialized)
 		}
-		return m.router6.AddNatRule(pair)
+		return m.family6.AddNatRule(pair)
 	}
 
-	if err := m.router.AddNatRule(pair); err != nil {
+	if err := m.family4.AddNatRule(pair); err != nil {
 		return err
 	}
 
@@ -284,7 +230,7 @@ func (m *Manager) AddNatRule(pair firewall.RouterPair) error {
 	// wildcard 0.0.0.0/0 destination where the client resolves DNS.
 	if m.hasIPv6() && pair.Dynamic {
 		v6Pair := firewall.ToV6NatPair(pair)
-		if err := m.router6.AddNatRule(v6Pair); err != nil {
+		if err := m.family6.AddNatRule(v6Pair); err != nil {
 			return fmt.Errorf("add v6 NAT rule: %w", err)
 		}
 	}
@@ -300,18 +246,18 @@ func (m *Manager) RemoveNatRule(pair firewall.RouterPair) error {
 		if !m.hasIPv6() {
 			return nil
 		}
-		return m.router6.RemoveNatRule(pair)
+		return m.family6.RemoveNatRule(pair)
 	}
 
 	var merr *multierror.Error
 
-	if err := m.router.RemoveNatRule(pair); err != nil {
+	if err := m.family4.RemoveNatRule(pair); err != nil {
 		merr = multierror.Append(merr, fmt.Errorf("remove v4 NAT rule: %w", err))
 	}
 
 	if m.hasIPv6() && pair.Dynamic {
 		v6Pair := firewall.ToV6NatPair(pair)
-		if err := m.router6.RemoveNatRule(v6Pair); err != nil {
+		if err := m.family6.RemoveNatRule(v6Pair); err != nil {
 			merr = multierror.Append(merr, fmt.Errorf("remove v6 NAT rule: %w", err))
 		}
 	}
@@ -320,11 +266,11 @@ func (m *Manager) RemoveNatRule(pair firewall.RouterPair) error {
 }
 
 func (m *Manager) SetLegacyManagement(isLegacy bool) error {
-	if err := firewall.SetLegacyManagement(m.router, isLegacy); err != nil {
+	if err := firewall.SetLegacyManagement(m.family4, isLegacy); err != nil {
 		return err
 	}
 	if m.hasIPv6() {
-		return firewall.SetLegacyManagement(m.router6, isLegacy)
+		return firewall.SetLegacyManagement(m.family6, isLegacy)
 	}
 	return nil
 }
@@ -341,19 +287,13 @@ func (m *Manager) Close(stateManager *statemanager.Manager) error {
 	}
 
 	if m.hasIPv6() {
-		if err := m.aclMgr6.Reset(); err != nil {
-			merr = multierror.Append(merr, fmt.Errorf("reset v6 acl manager: %w", err))
-		}
-		if err := m.router6.Reset(); err != nil {
-			merr = multierror.Append(merr, fmt.Errorf("reset v6 router: %w", err))
+		if err := m.family6.Reset(); err != nil {
+			merr = multierror.Append(merr, fmt.Errorf("reset v6 family: %w", err))
 		}
 	}
 
-	if err := m.aclMgr.Reset(); err != nil {
-		merr = multierror.Append(merr, fmt.Errorf("reset acl manager: %w", err))
-	}
-	if err := m.router.Reset(); err != nil {
-		merr = multierror.Append(merr, fmt.Errorf("reset router: %w", err))
+	if err := m.family4.Reset(); err != nil {
+		merr = multierror.Append(merr, fmt.Errorf("reset family: %w", err))
 	}
 
 	// Appending to merr intentionally blocks DeleteState below so ShutdownState
@@ -377,11 +317,11 @@ func (m *Manager) Close(stateManager *statemanager.Manager) error {
 // rules so that packet filtering is handled in userspace instead of by netfilter.
 func (m *Manager) AllowNetbird() error {
 	var merr *multierror.Error
-	if _, err := m.AddPeerFiltering(nil, net.IP{0, 0, 0, 0}, firewall.ProtocolALL, nil, nil, firewall.ActionAccept, ""); err != nil {
+	if _, err := m.AddFilterRule(nil, []netip.Prefix{netip.PrefixFrom(netip.IPv4Unspecified(), 0)}, firewall.Network{}, firewall.ProtocolALL, nil, nil, firewall.ActionAccept); err != nil {
 		merr = multierror.Append(merr, fmt.Errorf("allow netbird v4 interface traffic: %w", err))
 	}
 	if m.hasIPv6() {
-		if _, err := m.AddPeerFiltering(nil, net.IPv6zero, firewall.ProtocolALL, nil, nil, firewall.ActionAccept, ""); err != nil {
+		if _, err := m.AddFilterRule(nil, []netip.Prefix{netip.PrefixFrom(netip.IPv6Unspecified(), 0)}, firewall.Network{}, firewall.ProtocolALL, nil, nil, firewall.ActionAccept); err != nil {
 			merr = multierror.Append(merr, fmt.Errorf("allow netbird v6 interface traffic: %w", err))
 		}
 	}
@@ -402,14 +342,14 @@ func (m *Manager) SetLogLevel(log.Level) {
 }
 
 func (m *Manager) EnableRouting() error {
-	if err := m.router.ipFwdState.RequestForwarding(); err != nil {
+	if err := m.family4.ipFwdState.RequestForwarding(); err != nil {
 		return fmt.Errorf("enable IP forwarding: %w", err)
 	}
 	return nil
 }
 
 func (m *Manager) DisableRouting() error {
-	if err := m.router.ipFwdState.ReleaseForwarding(); err != nil {
+	if err := m.family4.ipFwdState.ReleaseForwarding(); err != nil {
 		return fmt.Errorf("disable IP forwarding: %w", err)
 	}
 	return nil
@@ -424,9 +364,9 @@ func (m *Manager) AddDNATRule(rule firewall.ForwardRule) (firewall.Rule, error)
 		if !m.hasIPv6() {
 			return nil, fmt.Errorf("add DNAT rule: %w", firewall.ErrIPv6NotInitialized)
 		}
-		return m.router6.AddDNATRule(rule)
+		return m.family6.AddDNATRule(rule)
 	}
-	return m.router.AddDNATRule(rule)
+	return m.family4.AddDNATRule(rule)
 }
 
 // DeleteDNATRule deletes a DNAT rule
@@ -434,10 +374,10 @@ func (m *Manager) DeleteDNATRule(rule firewall.Rule) error {
 	m.mutex.Lock()
 	defer m.mutex.Unlock()
 
-	if m.hasIPv6() && !m.router.hasRule(rule.ID()+dnatSuffix) {
-		return m.router6.DeleteDNATRule(rule)
+	if m.hasIPv6() && !m.family4.hasDNATRule(rule.ID()) {
+		return m.family6.DeleteDNATRule(rule)
 	}
-	return m.router.DeleteDNATRule(rule)
+	return m.family4.DeleteDNATRule(rule)
 }
 
 // UpdateSet updates the set with the given prefixes
@@ -454,12 +394,12 @@ func (m *Manager) UpdateSet(set firewall.Set, prefixes []netip.Prefix) error {
 		}
 	}
 
-	if err := m.router.UpdateSet(set, v4Prefixes); err != nil {
+	if err := m.family4.UpdateSet(set, v4Prefixes); err != nil {
 		return err
 	}
 
 	if m.hasIPv6() && len(v6Prefixes) > 0 {
-		if err := m.router6.UpdateSet(set, v6Prefixes); err != nil {
+		if err := m.family6.UpdateSet(set, v6Prefixes); err != nil {
 			return fmt.Errorf("update v6 set: %w", err)
 		}
 	}
@@ -476,9 +416,9 @@ func (m *Manager) AddInboundDNAT(localAddr netip.Addr, protocol firewall.Protoco
 		if !m.hasIPv6() {
 			return fmt.Errorf("add inbound DNAT: %w", firewall.ErrIPv6NotInitialized)
 		}
-		return m.router6.AddInboundDNAT(localAddr, protocol, originalPort, translatedPort)
+		return m.family6.AddInboundDNAT(localAddr, protocol, originalPort, translatedPort)
 	}
-	return m.router.AddInboundDNAT(localAddr, protocol, originalPort, translatedPort)
+	return m.family4.AddInboundDNAT(localAddr, protocol, originalPort, translatedPort)
 }
 
 // RemoveInboundDNAT removes an inbound DNAT rule.
@@ -490,9 +430,9 @@ func (m *Manager) RemoveInboundDNAT(localAddr netip.Addr, protocol firewall.Prot
 		if !m.hasIPv6() {
 			return fmt.Errorf("remove inbound DNAT: %w", firewall.ErrIPv6NotInitialized)
 		}
-		return m.router6.RemoveInboundDNAT(localAddr, protocol, originalPort, translatedPort)
+		return m.family6.RemoveInboundDNAT(localAddr, protocol, originalPort, translatedPort)
 	}
-	return m.router.RemoveInboundDNAT(localAddr, protocol, originalPort, translatedPort)
+	return m.family4.RemoveInboundDNAT(localAddr, protocol, originalPort, translatedPort)
 }
 
 // AddOutputDNAT adds an OUTPUT chain DNAT rule for locally-generated traffic.
@@ -504,9 +444,9 @@ func (m *Manager) AddOutputDNAT(localAddr netip.Addr, protocol firewall.Protocol
 		if !m.hasIPv6() {
 			return fmt.Errorf("add output DNAT: %w", firewall.ErrIPv6NotInitialized)
 		}
-		return m.router6.AddOutputDNAT(localAddr, protocol, originalPort, translatedPort)
+		return m.family6.AddOutputDNAT(localAddr, protocol, originalPort, translatedPort)
 	}
-	return m.router.AddOutputDNAT(localAddr, protocol, originalPort, translatedPort)
+	return m.family4.AddOutputDNAT(localAddr, protocol, originalPort, translatedPort)
 }
 
 // RemoveOutputDNAT removes an OUTPUT chain DNAT rule.
@@ -518,14 +458,14 @@ func (m *Manager) RemoveOutputDNAT(localAddr netip.Addr, protocol firewall.Proto
 		if !m.hasIPv6() {
 			return fmt.Errorf("remove output DNAT: %w", firewall.ErrIPv6NotInitialized)
 		}
-		return m.router6.RemoveOutputDNAT(localAddr, protocol, originalPort, translatedPort)
+		return m.family6.RemoveOutputDNAT(localAddr, protocol, originalPort, translatedPort)
 	}
-	return m.router.RemoveOutputDNAT(localAddr, protocol, originalPort, translatedPort)
+	return m.family4.RemoveOutputDNAT(localAddr, protocol, originalPort, translatedPort)
 }
 
 const (
 	chainNameRaw = "NETBIRD-RAW"
-	chainOUTPUT  = "OUTPUT"
+	chainOutput  = "OUTPUT"
 	tableRaw     = "raw"
 )
 
@@ -600,15 +540,15 @@ func (m *Manager) initNoTrackChain() error {
 
 	jumpRule := []string{"-j", chainNameRaw}
 
-	if err := m.ipv4Client.InsertUnique(tableRaw, chainOUTPUT, 1, jumpRule...); err != nil {
+	if err := m.ipv4Client.InsertUnique(tableRaw, chainOutput, 1, jumpRule...); err != nil {
 		if delErr := m.ipv4Client.DeleteChain(tableRaw, chainNameRaw); delErr != nil {
 			log.Debugf("delete orphan chain: %v", delErr)
 		}
 		return fmt.Errorf("add output jump rule: %w", err)
 	}
 
-	if err := m.ipv4Client.InsertUnique(tableRaw, chainPREROUTING, 1, jumpRule...); err != nil {
-		if delErr := m.ipv4Client.DeleteIfExists(tableRaw, chainOUTPUT, jumpRule...); delErr != nil {
+	if err := m.ipv4Client.InsertUnique(tableRaw, chainPrerouting, 1, jumpRule...); err != nil {
+		if delErr := m.ipv4Client.DeleteIfExists(tableRaw, chainOutput, jumpRule...); delErr != nil {
 			log.Debugf("delete output jump rule: %v", delErr)
 		}
 		if delErr := m.ipv4Client.DeleteChain(tableRaw, chainNameRaw); delErr != nil {
@@ -635,11 +575,11 @@ func (m *Manager) cleanupNoTrackChain() error {
 
 	jumpRule := []string{"-j", chainNameRaw}
 
-	if err := m.ipv4Client.DeleteIfExists(tableRaw, chainOUTPUT, jumpRule...); err != nil {
+	if err := m.ipv4Client.DeleteIfExists(tableRaw, chainOutput, jumpRule...); err != nil {
 		return fmt.Errorf("remove output jump rule: %w", err)
 	}
 
-	if err := m.ipv4Client.DeleteIfExists(tableRaw, chainPREROUTING, jumpRule...); err != nil {
+	if err := m.ipv4Client.DeleteIfExists(tableRaw, chainPrerouting, jumpRule...); err != nil {
 		return fmt.Errorf("remove prerouting jump rule: %w", err)
 	}
 
@@ -654,3 +594,13 @@ func (m *Manager) cleanupNoTrackChain() error {
 func getConntrackEstablished() []string {
 	return []string{"-m", "conntrack", "--ctstate", "RELATED,ESTABLISHED", "-j", "ACCEPT"}
 }
+
+// isIPv6Rule reports whether the rule belongs to the IPv6 family, from
+// the destination prefix when set, otherwise from the (single-family)
+// sources.
+func isIPv6Rule(sources []netip.Prefix, destination firewall.Network) bool {
+	if destination.IsPrefix() {
+		return destination.Prefix.Addr().Is6()
+	}
+	return len(sources) > 0 && sources[0].Addr().Is6()
+}

client/firewall/iptables/manager_linux_test.go

@@ -1,3 +1,5 @@
+//go:build integration && !android
+
 package iptables
 
 import (
@@ -65,46 +67,39 @@ func TestIptablesManager(t *testing.T) {
 		time.Sleep(time.Second)
 	}()
 
-	var rule2 []fw.Rule
+	var rule2 fw.Rule
 	t.Run("add second rule", func(t *testing.T) {
 		ip := netip.MustParseAddr("10.20.0.3")
 		port := &fw.Port{
 			IsRange: true,
 			Values:  []uint16{8043, 8046},
 		}
-		rule2, err = manager.AddPeerFiltering(nil, ip.AsSlice(), "tcp", port, nil, fw.ActionAccept, "")
+		rule2, err = manager.AddFilterRule(nil, pfx(ip.AsSlice()), fw.Network{}, "tcp", port, nil, fw.ActionAccept)
 		require.NoError(t, err, "failed to add rule")
 
-		for _, r := range rule2 {
-			rr := r.(*Rule)
-			checkRuleSpecs(t, ipv4Client, rr.chain, true, rr.specs...)
-		}
+		rr := rule2.(*Rule)
+		checkRuleSpecs(t, ipv4Client, rr.chain, true, rr.specs...)
 	})
 
 	t.Run("delete second rule", func(t *testing.T) {
-		for _, r := range rule2 {
-			err := manager.DeletePeerRule(r)
-			require.NoError(t, err, "failed to delete rule")
-		}
-
-		require.Empty(t, manager.aclMgr.ipsetStore.ipsets, "rulesets index after removed second rule must be empty")
+		require.NoError(t, manager.DeleteFilterRule(rule2), "failed to delete rule")
 	})
 
 	t.Run("reset check", func(t *testing.T) {
 		// add second rule
 		ip := netip.MustParseAddr("10.20.0.3")
 		port := &fw.Port{Values: []uint16{5353}}
-		_, err = manager.AddPeerFiltering(nil, ip.AsSlice(), "udp", nil, port, fw.ActionAccept, "")
+		_, err = manager.AddFilterRule(nil, pfx(ip.AsSlice()), fw.Network{}, "udp", nil, port, fw.ActionAccept)
 		require.NoError(t, err, "failed to add rule")
 
 		err = manager.Close(nil)
 		require.NoError(t, err, "failed to reset")
 
-		ok, err := ipv4Client.ChainExists("filter", chainNameInputRules)
+		ok, err := ipv4Client.ChainExists("filter", chainACLInput)
 		require.NoError(t, err, "failed check chain exists")
 
 		if ok {
-			require.NoErrorf(t, err, "chain '%v' still exists after Close", chainNameInputRules)
+			require.NoErrorf(t, err, "chain '%v' still exists after Close", chainACLInput)
 		}
 	})
 }
@@ -126,15 +121,13 @@ func TestIptablesManagerDenyRules(t *testing.T) {
 		ip := netip.MustParseAddr("10.20.0.3")
 		port := &fw.Port{Values: []uint16{22}}
 
-		rule, err := manager.AddPeerFiltering(nil, ip.AsSlice(), "tcp", nil, port, fw.ActionDrop, "deny-ssh")
+		rule, err := manager.AddFilterRule(nil, pfx(ip.AsSlice()), fw.Network{}, "tcp", nil, port, fw.ActionDrop)
 		require.NoError(t, err, "failed to add deny rule")
-		require.NotEmpty(t, rule, "deny rule should not be empty")
+		require.NotNil(t, rule, "deny rule should not be nil")
 
 		// Verify the rule was added by checking iptables
-		for _, r := range rule {
-			rr := r.(*Rule)
-			checkRuleSpecs(t, ipv4Client, rr.chain, true, rr.specs...)
-		}
+		rr := rule.(*Rule)
+		checkRuleSpecs(t, ipv4Client, rr.chain, true, rr.specs...)
 	})
 
 	t.Run("deny rule precedence test", func(t *testing.T) {
@@ -142,36 +135,40 @@ func TestIptablesManagerDenyRules(t *testing.T) {
 		port := &fw.Port{Values: []uint16{80}}
 
 		// Add accept rule first
-		_, err := manager.AddPeerFiltering(nil, ip.AsSlice(), "tcp", nil, port, fw.ActionAccept, "accept-http")
+		_, err := manager.AddFilterRule(nil, pfx(ip.AsSlice()), fw.Network{}, "tcp", nil, port, fw.ActionAccept)
 		require.NoError(t, err, "failed to add accept rule")
 
 		// Add deny rule second for same IP/port - this should take precedence
-		_, err = manager.AddPeerFiltering(nil, ip.AsSlice(), "tcp", nil, port, fw.ActionDrop, "deny-http")
+		_, err = manager.AddFilterRule(nil, pfx(ip.AsSlice()), fw.Network{}, "tcp", nil, port, fw.ActionDrop)
 		require.NoError(t, err, "failed to add deny rule")
 
 		// Inspect the actual iptables rules to verify deny rule comes before accept rule
-		rules, err := ipv4Client.List("filter", chainNameInputRules)
+		rules, err := ipv4Client.List("filter", chainACLInput)
 		require.NoError(t, err, "failed to list iptables rules")
 
 		// Debug: print all rules
-		t.Logf("All iptables rules in chain %s:", chainNameInputRules)
+		t.Logf("All iptables rules in chain %s:", chainACLInput)
 		for i, rule := range rules {
 			t.Logf("  [%d] %s", i, rule)
 		}
 
+		// Single-source rules emit a direct `-s <ip>/32 ... --dport 80`
+		// match. Match on that shape instead of the legacy
+		// per-(action,port) ipset names ("deny-http"/"accept-http")
+		// that this test predates.
+		srcMatch := fmt.Sprintf("-s %s/32", ip)
 		var denyRuleIndex, acceptRuleIndex = -1, -1
 		for i, rule := range rules {
-			if strings.Contains(rule, "DROP") {
-				t.Logf("Found DROP rule at index %d: %s", i, rule)
-				if strings.Contains(rule, "deny-http") && strings.Contains(rule, "80") {
-					denyRuleIndex = i
-				}
+			if !strings.Contains(rule, srcMatch) || !strings.Contains(rule, "--dport 80") {
+				continue
 			}
-			if strings.Contains(rule, "ACCEPT") {
+			if strings.Contains(rule, "-j DROP") {
+				t.Logf("Found DROP rule at index %d: %s", i, rule)
+				denyRuleIndex = i
+			}
+			if strings.Contains(rule, "-j ACCEPT") {
 				t.Logf("Found ACCEPT rule at index %d: %s", i, rule)
-				if strings.Contains(rule, "accept-http") && strings.Contains(rule, "80") {
-					acceptRuleIndex = i
-				}
+				acceptRuleIndex = i
 			}
 		}
 
@@ -196,7 +193,6 @@ func TestIptablesManagerIPSet(t *testing.T) {
 		},
 	}
 
-	// just check on the local interface
 	manager, err := Create(mock, iface.DefaultMTU)
 	require.NoError(t, err)
 	require.NoError(t, manager.Init(nil))
@@ -210,27 +206,39 @@ func TestIptablesManagerIPSet(t *testing.T) {
 		time.Sleep(time.Second)
 	}()
 
-	var rule2 []fw.Rule
-	t.Run("add second rule", func(t *testing.T) {
+	var rule2 fw.Rule
+	t.Run("single source uses direct -s match (no ipset)", func(t *testing.T) {
 		ip := netip.MustParseAddr("10.20.0.3")
 		port := &fw.Port{
 			Values: []uint16{443},
 		}
-		rule2, err = manager.AddPeerFiltering(nil, ip.AsSlice(), "tcp", port, nil, fw.ActionAccept, "default")
-		for _, r := range rule2 {
-			require.NoError(t, err, "failed to add rule")
-			require.Equal(t, r.(*Rule).ipsetName, "default-sport", "ipset name must be set")
-			require.Equal(t, r.(*Rule).ip, "10.20.0.3", "ipset IP must be set")
-		}
+		rule2, err = manager.AddFilterRule(nil, pfx(ip.AsSlice()), fw.Network{}, "tcp", port, nil, fw.ActionAccept)
+		require.NoError(t, err, "failed to add rule")
+		require.NotNil(t, rule2)
+		require.Contains(t, rule2.(*Rule).specs, "-s",
+			"single-source rule should use direct -s match, not an ipset")
+		require.Empty(t, findSets(rule2.(*Rule).specs),
+			"single-source rule should not allocate a shared ipset")
 	})
 
-	t.Run("delete second rule", func(t *testing.T) {
-		for _, r := range rule2 {
-			err := manager.DeletePeerRule(r)
-			require.NoError(t, err, "failed to delete rule")
+	t.Run("delete single-source rule", func(t *testing.T) {
+		require.NoError(t, manager.DeleteFilterRule(rule2), "failed to delete rule")
+	})
 
-			require.Empty(t, manager.aclMgr.ipsetStore.ipsets, "rulesets index after removed second rule must be empty")
+	t.Run("multi-source uses shared ipset", func(t *testing.T) {
+		sources := []netip.Prefix{
+			netip.PrefixFrom(netip.MustParseAddr("10.20.0.3"), 32),
+			netip.PrefixFrom(netip.MustParseAddr("10.20.0.4"), 32),
+			netip.PrefixFrom(netip.MustParseAddr("10.20.0.5"), 32),
 		}
+		port := &fw.Port{Values: []uint16{8080}}
+		multi, err := manager.AddFilterRule(nil, sources, fw.Network{}, "tcp", nil, port, fw.ActionAccept)
+		require.NoError(t, err, "failed to add multi-source rule")
+		require.NotNil(t, multi, "multi-source rule must produce one iptables rule")
+		sets := findSets(multi.(*Rule).specs)
+		require.Len(t, sets, 1, "multi-source rule must reference exactly one ipset")
+
+		require.NoError(t, manager.DeleteFilterRule(multi))
 	})
 
 	t.Run("reset check", func(t *testing.T) {
@@ -281,7 +289,7 @@ func TestIptablesCreatePerformance(t *testing.T) {
 			start := time.Now()
 			for i := 0; i < testMax; i++ {
 				port := &fw.Port{Values: []uint16{uint16(1000 + i)}}
-				_, err = manager.AddPeerFiltering(nil, ip.AsSlice(), "tcp", nil, port, fw.ActionAccept, "")
+				_, err = manager.AddFilterRule(nil, pfx(ip.AsSlice()), fw.Network{}, "tcp", nil, port, fw.ActionAccept)
 
 				require.NoError(t, err, "failed to add rule")
 			}

client/firewall/iptables/router_linux_test.go

@@ -1,4 +1,4 @@
-//go:build !android
+//go:build integration && !android
 
 package iptables
 
@@ -31,7 +31,7 @@ func TestIptablesManager_RestoreOrCreateContainers(t *testing.T) {
 	iptablesClient, err := iptables.NewWithProtocol(iptables.ProtocolIPv4)
 	require.NoError(t, err, "failed to init iptables client")
 
-	manager, err := newRouter(iptablesClient, ifaceMock, iface.DefaultMTU)
+	manager, err := newFamily(iptablesClient, ifaceMock, iface.DefaultMTU)
 	require.NoError(t, err, "should return a valid iptables manager")
 	require.NoError(t, manager.init(nil))
 
@@ -52,12 +52,12 @@ func TestIptablesManager_RestoreOrCreateContainers(t *testing.T) {
 	// 11. MSS clamping rule for outbound traffic
 	require.Len(t, manager.rules, 11, "should have created rules map")
 
-	exists, err := manager.iptablesClient.Exists(tableNat, chainPOSTROUTING, "-j", chainRTNAT)
-	require.NoError(t, err, "should be able to query the iptables %s table and %s chain", tableNat, chainPOSTROUTING)
+	exists, err := manager.iptablesClient.Exists(tableNat, chainPostrouting, "-j", chainRTNAT)
+	require.NoError(t, err, "should be able to query the iptables %s table and %s chain", tableNat, chainPostrouting)
 	require.True(t, exists, "postrouting jump rule should exist")
 
-	exists, err = manager.iptablesClient.Exists(tableMangle, chainPREROUTING, "-j", chainRTPRE)
-	require.NoError(t, err, "should be able to query the iptables %s table and %s chain", tableMangle, chainPREROUTING)
+	exists, err = manager.iptablesClient.Exists(tableMangle, chainPrerouting, "-j", chainRTPre)
+	require.NoError(t, err, "should be able to query the iptables %s table and %s chain", tableMangle, chainPrerouting)
 	require.True(t, exists, "prerouting jump rule should exist")
 
 	pair := firewall.RouterPair{
@@ -84,7 +84,7 @@ func TestIptablesManager_AddNatRule(t *testing.T) {
 			iptablesClient, err := iptables.NewWithProtocol(iptables.ProtocolIPv4)
 			require.NoError(t, err, "failed to init iptables client")
 
-			manager, err := newRouter(iptablesClient, ifaceMock, iface.DefaultMTU)
+			manager, err := newFamily(iptablesClient, ifaceMock, iface.DefaultMTU)
 			require.NoError(t, err, "shouldn't return error")
 			require.NoError(t, manager.init(nil))
 
@@ -95,7 +95,7 @@ func TestIptablesManager_AddNatRule(t *testing.T) {
 			err = manager.AddNatRule(testCase.InputPair)
 			require.NoError(t, err, "marking rule should be inserted")
 
-			natRuleKey := firewall.GenKey(firewall.NatFormat, testCase.InputPair)
+			natRuleKey := testCase.InputPair.GenKey(firewall.NatFormat)
 			markingRule := []string{
 				"-i", ifaceMock.Name(),
 				"-m", "conntrack",
@@ -106,8 +106,8 @@ func TestIptablesManager_AddNatRule(t *testing.T) {
 				fmt.Sprintf("%#x", nbnet.PreroutingFwmarkMasquerade),
 			}
 
-			exists, err := iptablesClient.Exists(tableMangle, chainRTPRE, markingRule...)
-			require.NoError(t, err, "should be able to query the iptables %s table and %s chain", tableMangle, chainRTPRE)
+			exists, err := iptablesClient.Exists(tableMangle, chainRTPre, markingRule...)
+			require.NoError(t, err, "should be able to query the iptables %s table and %s chain", tableMangle, chainRTPre)
 			if testCase.InputPair.Masquerade {
 				require.True(t, exists, "marking rule should be created")
 				foundRule, found := manager.rules[natRuleKey]
@@ -121,7 +121,7 @@ func TestIptablesManager_AddNatRule(t *testing.T) {
 
 			// Check inverse rule
 			inversePair := firewall.GetInversePair(testCase.InputPair)
-			inverseRuleKey := firewall.GenKey(firewall.NatFormat, inversePair)
+			inverseRuleKey := inversePair.GenKey(firewall.NatFormat)
 			inverseMarkingRule := []string{
 				"!", "-i", ifaceMock.Name(),
 				"-m", "conntrack",
@@ -132,8 +132,8 @@ func TestIptablesManager_AddNatRule(t *testing.T) {
 				fmt.Sprintf("%#x", nbnet.PreroutingFwmarkMasqueradeReturn),
 			}
 
-			exists, err = iptablesClient.Exists(tableMangle, chainRTPRE, inverseMarkingRule...)
-			require.NoError(t, err, "should be able to query the iptables %s table and %s chain", tableMangle, chainRTPRE)
+			exists, err = iptablesClient.Exists(tableMangle, chainRTPre, inverseMarkingRule...)
+			require.NoError(t, err, "should be able to query the iptables %s table and %s chain", tableMangle, chainRTPre)
 			if testCase.InputPair.Masquerade {
 				require.True(t, exists, "inverse marking rule should be created")
 				foundRule, found := manager.rules[inverseRuleKey]
@@ -157,7 +157,7 @@ func TestIptablesManager_RemoveNatRule(t *testing.T) {
 		t.Run(testCase.Name, func(t *testing.T) {
 			iptablesClient, _ := iptables.NewWithProtocol(iptables.ProtocolIPv4)
 
-			manager, err := newRouter(iptablesClient, ifaceMock, iface.DefaultMTU)
+			manager, err := newFamily(iptablesClient, ifaceMock, iface.DefaultMTU)
 			require.NoError(t, err, "shouldn't return error")
 			require.NoError(t, manager.init(nil))
 			defer func() {
@@ -170,7 +170,7 @@ func TestIptablesManager_RemoveNatRule(t *testing.T) {
 			err = manager.RemoveNatRule(testCase.InputPair)
 			require.NoError(t, err, "shouldn't return error")
 
-			natRuleKey := firewall.GenKey(firewall.NatFormat, testCase.InputPair)
+			natRuleKey := testCase.InputPair.GenKey(firewall.NatFormat)
 			markingRule := []string{
 				"-i", ifaceMock.Name(),
 				"-m", "conntrack",
@@ -181,8 +181,8 @@ func TestIptablesManager_RemoveNatRule(t *testing.T) {
 				fmt.Sprintf("%#x", nbnet.PreroutingFwmarkMasquerade),
 			}
 
-			exists, err := iptablesClient.Exists(tableMangle, chainRTPRE, markingRule...)
-			require.NoError(t, err, "should be able to query the iptables %s table and %s chain", tableMangle, chainRTPRE)
+			exists, err := iptablesClient.Exists(tableMangle, chainRTPre, markingRule...)
+			require.NoError(t, err, "should be able to query the iptables %s table and %s chain", tableMangle, chainRTPre)
 			require.False(t, exists, "marking rule should not exist")
 
 			_, found := manager.rules[natRuleKey]
@@ -190,7 +190,7 @@ func TestIptablesManager_RemoveNatRule(t *testing.T) {
 
 			// Check inverse rule removal
 			inversePair := firewall.GetInversePair(testCase.InputPair)
-			inverseRuleKey := firewall.GenKey(firewall.NatFormat, inversePair)
+			inverseRuleKey := inversePair.GenKey(firewall.NatFormat)
 			inverseMarkingRule := []string{
 				"!", "-i", ifaceMock.Name(),
 				"-m", "conntrack",
@@ -201,8 +201,8 @@ func TestIptablesManager_RemoveNatRule(t *testing.T) {
 				fmt.Sprintf("%#x", nbnet.PreroutingFwmarkMasqueradeReturn),
 			}
 
-			exists, err = iptablesClient.Exists(tableMangle, chainRTPRE, inverseMarkingRule...)
-			require.NoError(t, err, "should be able to query the iptables %s table and %s chain", tableMangle, chainRTPRE)
+			exists, err = iptablesClient.Exists(tableMangle, chainRTPre, inverseMarkingRule...)
+			require.NoError(t, err, "should be able to query the iptables %s table and %s chain", tableMangle, chainRTPre)
 			require.False(t, exists, "inverse marking rule should not exist")
 
 			_, found = manager.rules[inverseRuleKey]
@@ -219,13 +219,13 @@ func TestRouter_AddRouteFiltering(t *testing.T) {
 	iptablesClient, err := iptables.NewWithProtocol(iptables.ProtocolIPv4)
 	require.NoError(t, err, "Failed to create iptables client")
 
-	r, err := newRouter(iptablesClient, ifaceMock, iface.DefaultMTU)
-	require.NoError(t, err, "Failed to create router manager")
+	r, err := newFamily(iptablesClient, ifaceMock, iface.DefaultMTU)
+	require.NoError(t, err, "Failed to create family manager")
 	require.NoError(t, r.init(nil))
 
 	defer func() {
 		err := r.Reset()
-		require.NoError(t, err, "Failed to reset router")
+		require.NoError(t, err, "Failed to reset family")
 	}()
 
 	tests := []struct {
@@ -334,62 +334,30 @@ func TestRouter_AddRouteFiltering(t *testing.T) {
 
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
-			ruleKey, err := r.AddRouteFiltering(nil, tt.sources, firewall.Network{Prefix: tt.destination}, tt.proto, tt.sPort, tt.dPort, tt.action)
-			require.NoError(t, err, "AddRouteFiltering failed")
+			ruleKey, err := r.AddFilterRule(nil, tt.sources, firewall.Network{Prefix: tt.destination}, tt.proto, tt.sPort, tt.dPort, tt.action)
+			require.NoError(t, err, "AddFilterRule failed")
 
-			// Check if the rule is in the internal map
-			rule, ok := r.rules[ruleKey.ID()]
-			assert.True(t, ok, "Rule not found in internal map")
+			stored, ok := r.filters[ruleKey.ID()]
+			require.True(t, ok, "rule not stored in filters")
+			t.Logf("Internal rule: %v", stored.specs)
 
-			// Log the internal rule
-			t.Logf("Internal rule: %v", rule)
-
-			// Check if the rule exists in iptables
-			exists, err := iptablesClient.Exists(tableFilter, chainRTFWDIN, rule...)
+			exists, err := iptablesClient.Exists(tableFilter, chainRTFwdIn, stored.specs...)
 			assert.NoError(t, err, "Failed to check rule existence")
 			assert.True(t, exists, "Rule not found in iptables")
 
-			var source firewall.Network
-			if len(tt.sources) > 1 {
-				source.Set = firewall.NewPrefixSet(tt.sources)
-			} else if len(tt.sources) > 0 {
-				source.Prefix = tt.sources[0]
-			}
-			// Verify rule content
-			params := routeFilteringRuleParams{
-				Source:      source,
-				Destination: firewall.Network{Prefix: tt.destination},
-				Proto:       tt.proto,
-				SPort:       tt.sPort,
-				DPort:       tt.dPort,
-				Action:      tt.action,
-			}
-
-			expectedRule, err := r.genRouteRuleSpec(params, nil)
-			require.NoError(t, err, "Failed to generate expected rule spec")
-
 			if tt.expectSet {
 				setName := firewall.NewPrefixSet(tt.sources).HashedName()
-				expectedRule, err = r.genRouteRuleSpec(params, nil)
-				require.NoError(t, err, "Failed to generate expected rule spec with set")
-
-				// Check if the set was created
 				_, exists := r.ipsetCounter.Get(setName)
 				assert.True(t, exists, "IPSet not created")
+				assert.NotEmpty(t, findSets(stored.specs), "Rule should reference an ipset")
 			}
 
-			assert.Equal(t, expectedRule, rule, "Rule content mismatch")
-
-			// Clean up
-			err = r.DeleteRouteRule(ruleKey)
-			require.NoError(t, err, "Failed to delete rule")
+			require.NoError(t, r.DeleteFilterRule(ruleKey), "Failed to delete rule")
 		})
 	}
 }
 
 func TestFindSetNameInRule(t *testing.T) {
-	r := &router{}
-
 	testCases := []struct {
 		name     string
 		rule     []string
@@ -430,7 +398,7 @@ func TestFindSetNameInRule(t *testing.T) {
 
 	for _, tc := range testCases {
 		t.Run(tc.name, func(t *testing.T) {
-			result := r.findSets(tc.rule)
+			result := findSets(tc.rule)
 
 			if len(result) != len(tc.expected) {
 				t.Errorf("Expected %d sets, got %d. Sets found: %v", len(tc.expected), len(result), result)

client/firewall/iptables/routing_linux.go

@@ -0,0 +1,269 @@
+//go:build !android
+
+package iptables
+
+import (
+	"fmt"
+	"strings"
+
+	"github.com/hashicorp/go-multierror"
+	log "github.com/sirupsen/logrus"
+
+	nberrors "github.com/netbirdio/netbird/client/errors"
+	firewall "github.com/netbirdio/netbird/client/firewall/manager"
+	nbnet "github.com/netbirdio/netbird/client/net"
+)
+
+func (r *family) AddNatRule(pair firewall.RouterPair) error {
+	if r.legacyManagement {
+		log.Warnf("This peer is connected to a NetBird Management service with an older version. Allowing all traffic for %s", pair.Destination)
+		if err := r.addLegacyRouteRule(pair); err != nil {
+			return fmt.Errorf("add legacy routing rule: %w", err)
+		}
+	}
+
+	if !pair.Masquerade {
+		return nil
+	}
+
+	if err := r.addNatRule(pair); err != nil {
+		return fmt.Errorf("add nat rule: %w", err)
+	}
+
+	if err := r.addNatRule(firewall.GetInversePair(pair)); err != nil {
+		return fmt.Errorf("add inverse nat rule: %w", err)
+	}
+
+	r.updateState()
+
+	return nil
+}
+
+// RemoveNatRule removes an iptables rule pair from forwarding and nat chains
+func (r *family) RemoveNatRule(pair firewall.RouterPair) error {
+	if pair.Masquerade {
+		if err := r.removeNatRule(pair); err != nil {
+			return fmt.Errorf("remove nat rule: %w", err)
+		}
+
+		if err := r.removeNatRule(firewall.GetInversePair(pair)); err != nil {
+			return fmt.Errorf("remove inverse nat rule: %w", err)
+		}
+	}
+
+	if err := r.removeLegacyRouteRule(pair); err != nil {
+		return fmt.Errorf("remove legacy routing rule: %w", err)
+	}
+
+	r.updateState()
+
+	return nil
+}
+
+// addLegacyRouteRule adds a legacy routing rule for mgmt servers pre route acls
+func (r *family) addLegacyRouteRule(pair firewall.RouterPair) error {
+	ruleID := pair.GenKey(firewall.ForwardingFormat)
+
+	if err := r.removeLegacyRouteRule(pair); err != nil {
+		return err
+	}
+
+	rule := []string{"-s", pair.Source.String(), "-d", pair.Destination.String(), "-j", "ACCEPT"}
+	if err := r.iptablesClient.Append(tableFilter, chainRTFwdIn, rule...); err != nil {
+		return fmt.Errorf("add legacy forwarding rule %s -> %s: %w", pair.Source, pair.Destination, err)
+	}
+
+	r.rules[ruleID] = rule
+
+	return nil
+}
+
+func (r *family) removeLegacyRouteRule(pair firewall.RouterPair) error {
+	ruleID := pair.GenKey(firewall.ForwardingFormat)
+
+	if rule, exists := r.rules[ruleID]; exists {
+		if err := r.iptablesClient.DeleteIfExists(tableFilter, chainRTFwdIn, rule...); err != nil {
+			return fmt.Errorf("remove legacy forwarding rule %s -> %s: %w", pair.Source, pair.Destination, err)
+		}
+		delete(r.rules, ruleID)
+
+		if err := r.decrementSetCounter(rule); err != nil {
+			return fmt.Errorf("decrement ipset counter: %w", err)
+		}
+	}
+
+	return nil
+}
+
+// GetLegacyManagement returns the current legacy management mode
+func (r *family) GetLegacyManagement() bool {
+	return r.legacyManagement
+}
+
+// SetLegacyManagement sets the route manager to use legacy management mode
+func (r *family) SetLegacyManagement(isLegacy bool) {
+	r.legacyManagement = isLegacy
+}
+
+// RemoveAllLegacyRouteRules removes all legacy routing rules for mgmt servers pre route acls
+func (r *family) RemoveAllLegacyRouteRules() error {
+	var merr *multierror.Error
+	for k, rule := range r.rules {
+		if !strings.HasPrefix(string(k), firewall.ForwardingFormatPrefix) {
+			continue
+		}
+		if err := r.iptablesClient.DeleteIfExists(tableFilter, chainRTFwdIn, rule...); err != nil {
+			merr = multierror.Append(merr, fmt.Errorf("remove legacy forwarding rule: %w", err))
+		} else {
+			delete(r.rules, k)
+		}
+	}
+
+	r.updateState()
+
+	return nberrors.FormatErrorOrNil(merr)
+}
+
+func (r *family) addPostroutingRules() error {
+	// First rule for outbound masquerade
+	rule1 := []string{
+		"-m", "mark", "--mark", fmt.Sprintf("%#x", nbnet.PreroutingFwmarkMasquerade),
+		"!", "-o", "lo",
+		"-j", "MASQUERADE",
+	}
+	if err := r.iptablesClient.Append(tableNat, chainRTNAT, rule1...); err != nil {
+		return fmt.Errorf("add outbound masquerade rule: %w", err)
+	}
+	r.rules["static-nat-outbound"] = rule1
+
+	// Second rule for return traffic masquerade
+	rule2 := []string{
+		"-m", "mark", "--mark", fmt.Sprintf("%#x", nbnet.PreroutingFwmarkMasqueradeReturn),
+		"-o", r.wgIface.Name(),
+		"-j", "MASQUERADE",
+	}
+	if err := r.iptablesClient.Append(tableNat, chainRTNAT, rule2...); err != nil {
+		return fmt.Errorf("add return masquerade rule: %w", err)
+	}
+	r.rules["static-nat-return"] = rule2
+
+	return nil
+}
+
+// addMSSClampingRules adds MSS clamping rules to prevent fragmentation for forwarded traffic.
+func (r *family) addMSSClampingRules() error {
+	overhead := uint16(ipv4TCPHeaderSize)
+	if r.v6 {
+		overhead = ipv6TCPHeaderSize
+	}
+	mss := r.mtu - overhead
+
+	// Add jump rule from FORWARD chain in mangle table to our custom chain
+	jumpRule := []string{
+		"-j", chainRTMSSClamp,
+	}
+	if err := r.iptablesClient.Insert(tableMangle, chainForward, 1, jumpRule...); err != nil {
+		return fmt.Errorf("add jump to MSS clamp chain: %w", err)
+	}
+	r.rules[jumpMSSClamp] = jumpRule
+
+	ruleOut := []string{
+		"-o", r.wgIface.Name(),
+		"-p", "tcp",
+		"--tcp-flags", "SYN,RST", "SYN",
+		"-j", "TCPMSS",
+		"--set-mss", fmt.Sprintf("%d", mss),
+	}
+	if err := r.iptablesClient.Append(tableMangle, chainRTMSSClamp, ruleOut...); err != nil {
+		return fmt.Errorf("add outbound MSS clamp rule: %w", err)
+	}
+	r.rules["mss-clamp-out"] = ruleOut
+
+	return nil
+}
+
+func (r *family) insertEstablishedRule(chain string) error {
+	establishedRule := getConntrackEstablished()
+
+	err := r.iptablesClient.Insert(tableFilter, chain, 1, establishedRule...)
+	if err != nil {
+		return fmt.Errorf("insert established rule: %w", err)
+	}
+
+	ruleID := firewall.RuleID("established-" + chain)
+	r.rules[ruleID] = establishedRule
+
+	return nil
+}
+
+func (r *family) addNatRule(pair firewall.RouterPair) error {
+	ruleID := pair.GenKey(firewall.NatFormat)
+
+	if rule, exists := r.rules[ruleID]; exists {
+		if err := r.iptablesClient.DeleteIfExists(tableMangle, chainRTPre, rule...); err != nil {
+			return fmt.Errorf("remove existing marking rule for %s: %w", pair.Destination, err)
+		}
+		delete(r.rules, ruleID)
+	}
+
+	markValue := nbnet.PreroutingFwmarkMasquerade
+	if pair.Inverse {
+		markValue = nbnet.PreroutingFwmarkMasqueradeReturn
+	}
+
+	rule := []string{"-i", r.wgIface.Name()}
+	if pair.Inverse {
+		rule = []string{"!", "-i", r.wgIface.Name()}
+	}
+
+	rule = append(rule,
+		"-m", "conntrack",
+		"--ctstate", "NEW",
+	)
+	sourceExp, err := r.applyNetwork("-s", pair.Source, nil)
+	if err != nil {
+		return fmt.Errorf("apply network -s: %w", err)
+	}
+	destExp, err := r.applyNetwork("-d", pair.Destination, nil)
+	if err != nil {
+		return fmt.Errorf("apply network -d: %w", err)
+	}
+
+	rule = append(rule, sourceExp...)
+	rule = append(rule, destExp...)
+	rule = append(rule,
+		"-j", "MARK", "--set-mark", fmt.Sprintf("%#x", markValue),
+	)
+
+	// Ensure nat rules come first, so the mark can be overwritten.
+	// Currently overwritten by the dst-type LOCAL rules for redirected traffic.
+	if err := r.iptablesClient.Insert(tableMangle, chainRTPre, 1, rule...); err != nil {
+		r.dropSourceMatch(rule)
+		return fmt.Errorf("add marking rule for %s: %w", pair.Destination, err)
+	}
+
+	r.rules[ruleID] = rule
+
+	r.updateState()
+	return nil
+}
+
+func (r *family) removeNatRule(pair firewall.RouterPair) error {
+	ruleID := pair.GenKey(firewall.NatFormat)
+
+	if rule, exists := r.rules[ruleID]; exists {
+		if err := r.iptablesClient.DeleteIfExists(tableMangle, chainRTPre, rule...); err != nil {
+			return fmt.Errorf("remove marking rule for %s: %w", pair.Destination, err)
+		}
+		delete(r.rules, ruleID)
+
+		if err := r.decrementSetCounter(rule); err != nil {
+			return fmt.Errorf("decrement ipset counter: %w", err)
+		}
+	} else {
+		log.Debugf("marking rule %s not found", ruleID)
+	}
+
+	r.updateState()
+	return nil
+}

client/firewall/iptables/rule.go

@@ -1,18 +1,20 @@
 package iptables
 
-// Rule to handle management of rules
-type Rule struct {
-	ruleID    string
-	ipsetName string
+import "github.com/netbirdio/netbird/client/firewall/manager"
 
+// Rule to handle management of rules. Source set membership (when the
+// rule was built against a shared hash:net ipset) is encoded in specs;
+// DeleteFilterRule recovers it via findSets so the refcounter can drop
+// the right reference.
+type Rule struct {
+	id          manager.RuleID
 	specs       []string
 	mangleSpecs []string
-	ip          string
 	chain       string
 	v6          bool
 }
 
-// GetRuleID returns the rule id
-func (r *Rule) ID() string {
-	return r.ruleID
+// ID returns the rule id
+func (r *Rule) ID() manager.RuleID {
+	return r.id
 }

client/firewall/iptables/rulestore_linux.go

@@ -1,103 +0,0 @@
-package iptables
-
-import "encoding/json"
-
-type ipList struct {
-	ips map[string]struct{}
-}
-
-func newIpList(ip string) *ipList {
-	ips := make(map[string]struct{})
-	ips[ip] = struct{}{}
-
-	return &ipList{
-		ips: ips,
-	}
-}
-
-func (s *ipList) addIP(ip string) {
-	s.ips[ip] = struct{}{}
-}
-
-// MarshalJSON implements json.Marshaler
-func (s *ipList) MarshalJSON() ([]byte, error) {
-	return json.Marshal(struct {
-		IPs map[string]struct{} `json:"ips"`
-	}{
-		IPs: s.ips,
-	})
-}
-
-// UnmarshalJSON implements json.Unmarshaler
-func (s *ipList) UnmarshalJSON(data []byte) error {
-	temp := struct {
-		IPs map[string]struct{} `json:"ips"`
-	}{}
-	if err := json.Unmarshal(data, &temp); err != nil {
-		return err
-	}
-	s.ips = temp.IPs
-
-	if temp.IPs == nil {
-		temp.IPs = make(map[string]struct{})
-	}
-
-	return nil
-}
-
-type ipsetStore struct {
-	ipsets map[string]*ipList
-}
-
-func newIpsetStore() *ipsetStore {
-	return &ipsetStore{
-		ipsets: make(map[string]*ipList),
-	}
-}
-
-func (s *ipsetStore) ipset(ipsetName string) (*ipList, bool) {
-	r, ok := s.ipsets[ipsetName]
-	return r, ok
-}
-
-func (s *ipsetStore) addIpList(ipsetName string, list *ipList) {
-	s.ipsets[ipsetName] = list
-}
-
-func (s *ipsetStore) deleteIpset(ipsetName string) {
-	delete(s.ipsets, ipsetName)
-}
-
-func (s *ipsetStore) ipsetNames() []string {
-	names := make([]string, 0, len(s.ipsets))
-	for name := range s.ipsets {
-		names = append(names, name)
-	}
-	return names
-}
-
-// MarshalJSON implements json.Marshaler
-func (s *ipsetStore) MarshalJSON() ([]byte, error) {
-	return json.Marshal(struct {
-		IPSets map[string]*ipList `json:"ipsets"`
-	}{
-		IPSets: s.ipsets,
-	})
-}
-
-// UnmarshalJSON implements json.Unmarshaler
-func (s *ipsetStore) UnmarshalJSON(data []byte) error {
-	temp := struct {
-		IPSets map[string]*ipList `json:"ipsets"`
-	}{}
-	if err := json.Unmarshal(data, &temp); err != nil {
-		return err
-	}
-	s.ipsets = temp.IPSets
-
-	if temp.IPSets == nil {
-		temp.IPSets = make(map[string]*ipList)
-	}
-
-	return nil
-}

client/firewall/iptables/state_linux.go

@@ -29,17 +29,13 @@ type ShutdownState struct {
 
 	InterfaceState *InterfaceState `json:"interface_state,omitempty"`
 
-	RouteRules        routeRules    `json:"route_rules,omitempty"`
-	RouteIPsetCounter *ipsetCounter `json:"route_ipset_counter,omitempty"`
-
-	ACLEntries    aclEntries  `json:"acl_entries,omitempty"`
-	ACLIPsetStore *ipsetStore `json:"acl_ipset_store,omitempty"`
-
-	// IPv6 counterparts
+	RouteRules         routeRules    `json:"route_rules,omitempty"`
 	RouteRules6        routeRules    `json:"route_rules_v6,omitempty"`
+	RouteIPsetCounter  *ipsetCounter `json:"route_ipset_counter,omitempty"`
 	RouteIPsetCounter6 *ipsetCounter `json:"route_ipset_counter_v6,omitempty"`
-	ACLEntries6        aclEntries    `json:"acl_entries_v6,omitempty"`
-	ACLIPsetStore6     *ipsetStore   `json:"acl_ipset_store_v6,omitempty"`
+
+	ACLEntries  aclEntries `json:"acl_entries,omitempty"`
+	ACLEntries6 aclEntries `json:"acl_entries_v6,omitempty"`
 }
 
 func (s *ShutdownState) Name() string {
@@ -57,17 +53,14 @@ func (s *ShutdownState) Cleanup() error {
 	}
 
 	if s.RouteRules != nil {
-		ipt.router.rules = s.RouteRules
+		ipt.family4.rules = s.RouteRules
 	}
 	if s.RouteIPsetCounter != nil {
-		ipt.router.ipsetCounter.LoadData(s.RouteIPsetCounter)
+		ipt.family4.ipsetCounter.LoadData(s.RouteIPsetCounter)
 	}
 
 	if s.ACLEntries != nil {
-		ipt.aclMgr.entries = s.ACLEntries
-	}
-	if s.ACLIPsetStore != nil {
-		ipt.aclMgr.ipsetStore = s.ACLIPsetStore
+		ipt.family4.entries = s.ACLEntries
 	}
 
 	// Clean up v6 state even if the current run has no IPv6.
@@ -79,16 +72,13 @@ func (s *ShutdownState) Cleanup() error {
 	}
 	if ipt.hasIPv6() {
 		if s.RouteRules6 != nil {
-			ipt.router6.rules = s.RouteRules6
+			ipt.family6.rules = s.RouteRules6
 		}
 		if s.RouteIPsetCounter6 != nil {
-			ipt.router6.ipsetCounter.LoadData(s.RouteIPsetCounter6)
+			ipt.family6.ipsetCounter.LoadData(s.RouteIPsetCounter6)
 		}
 		if s.ACLEntries6 != nil {
-			ipt.aclMgr6.entries = s.ACLEntries6
-		}
-		if s.ACLIPsetStore6 != nil {
-			ipt.aclMgr6.ipsetStore = s.ACLIPsetStore6
+			ipt.family6.entries = s.ACLEntries6
 		}
 	}
 

client/firewall/iptables/testhelpers_linux_test.go

@@ -0,0 +1,27 @@
+//go:build integration && !android
+
+package iptables
+
+import (
+	"fmt"
+	"net"
+	"net/netip"
+)
+
+func pfx(ip net.IP) []netip.Prefix {
+	if ip == nil {
+		return []netip.Prefix{netip.PrefixFrom(netip.IPv4Unspecified(), 0)}
+	}
+	if ip.IsUnspecified() {
+		if ip.To4() != nil {
+			return []netip.Prefix{netip.PrefixFrom(netip.IPv4Unspecified(), 0)}
+		}
+		return []netip.Prefix{netip.PrefixFrom(netip.IPv6Unspecified(), 0)}
+	}
+	a, ok := netip.AddrFromSlice(ip)
+	if !ok {
+		panic(fmt.Sprintf("invalid IP length: %d", len(ip)))
+	}
+	a = a.Unmap()
+	return []netip.Prefix{netip.PrefixFrom(a, a.BitLen())}
+}

client/firewall/manager/firewall.go

@@ -3,7 +3,6 @@ package manager
 import (
 	"errors"
 	"fmt"
-	"net"
 	"net/netip"
 	"sort"
 
@@ -16,6 +15,12 @@ import (
 // method but the IPv6 firewall components were not initialized.
 var ErrIPv6NotInitialized = errors.New("IPv6 firewall not initialized")
 
+// ErrNoSources is returned when AddFilterRule is called with an empty
+// source list. "Match any source" must be expressed explicitly with a
+// /0 prefix; an empty list is a caller error and is rejected rather
+// than silently widening the rule to every source.
+var ErrNoSources = errors.New("rule has no sources")
+
 const (
 	ForwardingFormatPrefix = "netbird-fwd-"
 	ForwardingFormat       = "netbird-fwd-%s-%t"
@@ -23,13 +28,18 @@ const (
 	NatFormat              = "netbird-nat-%s-%t"
 )
 
+// RuleID identifies a firewall rule. It is a typed string so the
+// compiler catches accidental mixing with arbitrary string keys. It is
+// only an identifier and does not implement Rule.
+type RuleID string
+
 // Rule abstraction should be implemented by each firewall manager
 //
 // Each firewall type for different OS can use different type
 // of the properties to hold data of the created rule
 type Rule interface {
 	// ID returns the rule id
-	ID() string
+	ID() RuleID
 }
 
 // RuleDirection is the traffic direction which a rule is applied
@@ -91,6 +101,13 @@ func (d Network) IsPrefix() bool {
 	return d.Prefix.IsValid()
 }
 
+// IsZero returns true if the network designates no destination, i.e. it
+// is the zero value. A zero Network is the peer-rule sentinel; a non-zero
+// one carries a prefix or set destination.
+func (d Network) IsZero() bool {
+	return !d.IsPrefix() && !d.IsSet()
+}
+
 // Manager is the high level abstraction of a firewall manager
 //
 // It declares methods which handle actions required by the
@@ -101,43 +118,42 @@ type Manager interface {
 	// AllowNetbird allows netbird interface traffic
 	AllowNetbird() error
 
-	// AddPeerFiltering adds a rule to the firewall
+	// AddFilterRule adds a packet-filtering rule to the firewall.
 	//
-	// If comment argument is empty firewall manager should set
-	// rule ID as comment for the rule
+	// If destination is the zero Network, the rule applies to traffic
+	// inbound to this node, i.e. peer ACL semantics, installed in
+	// the kernel's input chain. If destination is set (prefix or
+	// set), the rule applies to forwarded traffic with that
+	// destination, route ACL semantics, installed in the forward
+	// chain.
 	//
-	// Note: Callers should call Flush() after adding rules to ensure
-	// they are applied to the kernel and rule handles are refreshed.
-	AddPeerFiltering(
+	// sources must be a single address family; the caller splits mixed
+	// families and calls once per family. "Match any source" must be
+	// expressed with an explicit /0 prefix; an empty sources list is
+	// rejected with ErrNoSources so a zeroed list can never widen a
+	// rule to every source.
+	//
+	// Note: callers should call Flush() after adding rules.
+	AddFilterRule(
 		id []byte,
-		ip net.IP,
+		sources []netip.Prefix,
+		destination Network,
 		proto Protocol,
 		sPort *Port,
 		dPort *Port,
 		action Action,
-		ipsetName string,
-	) ([]Rule, error)
+	) (Rule, error)
 
-	// DeletePeerRule from the firewall by rule definition
-	DeletePeerRule(rule Rule) error
+	// DeleteFilterRule removes a filtering rule previously added via
+	// AddFilterRule. The rule's own type identifies whether it lives
+	// in the peer (input) or route (forward) path.
+	DeleteFilterRule(rule Rule) error
 
 	// IsServerRouteSupported returns true if the firewall supports server side routing operations
 	IsServerRouteSupported() bool
 
 	IsStateful() bool
 
-	AddRouteFiltering(
-		id []byte,
-		sources []netip.Prefix,
-		destination Network,
-		proto Protocol,
-		sPort, dPort *Port,
-		action Action,
-	) (Rule, error)
-
-	// DeleteRouteRule deletes a routing rule
-	DeleteRouteRule(rule Rule) error
-
 	// AddNatRule inserts a routing NAT rule
 	AddNatRule(pair RouterPair) error
 
@@ -185,8 +201,9 @@ type Manager interface {
 	SetupEBPFProxyNoTrack(proxyPort, wgPort uint16) error
 }
 
-func GenKey(format string, pair RouterPair) string {
-	return fmt.Sprintf(format, pair.ID, pair.Inverse)
+// GenKey builds the rule id for this pair from the given format.
+func (p RouterPair) GenKey(format string) RuleID {
+	return RuleID(fmt.Sprintf(format, p.ID, p.Inverse))
 }
 
 // LegacyManager defines the interface for legacy management operations
@@ -242,6 +259,20 @@ func MergeIPRanges(prefixes []netip.Prefix) []netip.Prefix {
 	return merged
 }
 
+// UnmapPrefix normalizes a v4-mapped v6 prefix (::ffff:a.b.c.d) to its
+// plain v4 form, shifting the prefix length out of the 96-bit mapped
+// range. Other prefixes are returned unchanged. Keeping prefixes
+// unmapped ensures v4 rules match consistently and the match builders
+// read the correct address length.
+func UnmapPrefix(p netip.Prefix) netip.Prefix {
+	addr := p.Addr()
+	if !addr.Is4In6() {
+		return p
+	}
+	bits := max(p.Bits()-96, 0)
+	return netip.PrefixFrom(addr.Unmap(), bits)
+}
+
 // SortPrefixes sorts the given slice of netip.Prefix in place.
 // It sorts first by IP address, then by prefix length (most specific to least specific).
 func SortPrefixes(prefixes []netip.Prefix) {

client/firewall/manager/forward_rule.go

@@ -13,13 +13,13 @@ type ForwardRule struct {
 	TranslatedPort    Port
 }
 
-func (r ForwardRule) ID() string {
+func (r ForwardRule) ID() RuleID {
 	id := fmt.Sprintf("%s;%s;%s;%s",
 		r.Protocol,
 		r.DestinationPort.String(),
 		r.TranslatedAddress.String(),
 		r.TranslatedPort.String())
-	return id
+	return RuleID(id)
 }
 
 func (r ForwardRule) String() string {

client/firewall/manager/set.go

@@ -40,7 +40,7 @@ func (h Set) Comment() string {
 
 // NewPrefixSet generates a unique name for an ipset based on the given prefixes.
 func NewPrefixSet(prefixes []netip.Prefix) Set {
-	// sort for consistent naming
+	prefixes = slices.Clone(prefixes)
 	SortPrefixes(prefixes)
 
 	hash := sha256.New()

client/firewall/nftables/acl_linux.go

@@ -1,713 +0,0 @@
-package nftables
-
-import (
-	"bytes"
-	"fmt"
-	"net"
-	"slices"
-	"strconv"
-	"strings"
-	"time"
-
-	"github.com/google/nftables"
-	"github.com/google/nftables/binaryutil"
-	"github.com/google/nftables/expr"
-	log "github.com/sirupsen/logrus"
-	"golang.org/x/sys/unix"
-
-	firewall "github.com/netbirdio/netbird/client/firewall/manager"
-	nbnet "github.com/netbirdio/netbird/client/net"
-)
-
-const (
-
-	// rules chains contains the effective ACL rules
-	chainNameInputRules = "netbird-acl-input-rules"
-
-	// filter chains contains the rules that jump to the rules chains
-	chainNameInputFilter       = "netbird-acl-input-filter"
-	chainNameForwardFilter     = "netbird-acl-forward-filter"
-	chainNameManglePrerouting  = "netbird-mangle-prerouting"
-	chainNameManglePostrouting = "netbird-mangle-postrouting"
-)
-
-const flushError = "flush: %w"
-
-type AclManager struct {
-	rConn              *nftables.Conn
-	sConn              *nftables.Conn
-	wgIface            iFaceMapper
-	routingFwChainName string
-	af                 addrFamily
-
-	workTable       *nftables.Table
-	chainInputRules *nftables.Chain
-	chainPrerouting *nftables.Chain
-
-	ipsetStore *ipsetStore
-	rules      map[string]*Rule
-}
-
-func newAclManager(table *nftables.Table, wgIface iFaceMapper, routingFwChainName string) (*AclManager, error) {
-	// sConn is used for creating sets and adding/removing elements from them
-	// it's differ then rConn (which does create new conn for each flush operation)
-	// and is permanent. Using same connection for both type of operations
-	// overloads netlink with high amount of rules ( > 10000)
-	sConn, err := nftables.New(nftables.AsLasting())
-	if err != nil {
-		return nil, fmt.Errorf("create nf conn: %w", err)
-	}
-
-	return &AclManager{
-		rConn:              &nftables.Conn{},
-		sConn:              sConn,
-		wgIface:            wgIface,
-		workTable:          table,
-		routingFwChainName: routingFwChainName,
-		af:                 familyForAddr(table.Family == nftables.TableFamilyIPv4),
-
-		ipsetStore: newIpsetStore(),
-		rules:      make(map[string]*Rule),
-	}, nil
-}
-
-func (m *AclManager) init(workTable *nftables.Table) error {
-	m.workTable = workTable
-	return m.createDefaultChains()
-}
-
-// AddPeerFiltering rule to the firewall
-//
-// If comment argument is empty firewall manager should set
-// rule ID as comment for the rule
-func (m *AclManager) AddPeerFiltering(
-	id []byte,
-	ip net.IP,
-	proto firewall.Protocol,
-	sPort *firewall.Port,
-	dPort *firewall.Port,
-	action firewall.Action,
-	ipsetName string,
-) ([]firewall.Rule, error) {
-	var ipset *nftables.Set
-	if ipsetName != "" {
-		var err error
-		ipset, err = m.addIpToSet(ipsetName, ip)
-		if err != nil {
-			return nil, err
-		}
-	}
-
-	newRules := make([]firewall.Rule, 0, 2)
-	ioRule, err := m.addIOFiltering(ip, proto, sPort, dPort, action, ipset)
-	if err != nil {
-		return nil, err
-	}
-
-	newRules = append(newRules, ioRule)
-	return newRules, nil
-}
-
-// DeletePeerRule from the firewall by rule definition
-func (m *AclManager) DeletePeerRule(rule firewall.Rule) error {
-	r, ok := rule.(*Rule)
-	if !ok {
-		return fmt.Errorf("invalid rule type")
-	}
-
-	if r.nftSet == nil {
-		if err := m.rConn.DelRule(r.nftRule); err != nil {
-			log.Errorf("failed to delete rule: %v", err)
-		}
-		if r.mangleRule != nil {
-			if err := m.rConn.DelRule(r.mangleRule); err != nil {
-				log.Errorf("failed to delete mangle rule: %v", err)
-			}
-		}
-		delete(m.rules, r.ID())
-		return m.rConn.Flush()
-	}
-
-	ips, ok := m.ipsetStore.ips(r.nftSet.Name)
-	if !ok {
-		if err := m.rConn.DelRule(r.nftRule); err != nil {
-			log.Errorf("failed to delete rule: %v", err)
-		}
-		if r.mangleRule != nil {
-			if err := m.rConn.DelRule(r.mangleRule); err != nil {
-				log.Errorf("failed to delete mangle rule: %v", err)
-			}
-		}
-		delete(m.rules, r.ID())
-		return m.rConn.Flush()
-	}
-
-	if _, ok := ips[r.ip.String()]; ok {
-		err := m.sConn.SetDeleteElements(r.nftSet, []nftables.SetElement{{Key: ipToBytes(r.ip, m.af)}})
-		if err != nil {
-			log.Errorf("delete elements for set %q: %v", r.nftSet.Name, err)
-		}
-		if err := m.sConn.Flush(); err != nil {
-			log.Debugf("flush error of set delete element, %s", r.nftSet.Name)
-			return err
-		}
-		m.ipsetStore.DeleteIpFromSet(r.nftSet.Name, r.ip)
-	}
-
-	// if after delete, set still contains other IPs,
-	// no need to delete firewall rule and we should exit here
-	if len(ips) > 0 {
-		return nil
-	}
-
-	if err := m.rConn.DelRule(r.nftRule); err != nil {
-		log.Errorf("failed to delete rule: %v", err)
-	}
-	if r.mangleRule != nil {
-		if err := m.rConn.DelRule(r.mangleRule); err != nil {
-			log.Errorf("failed to delete mangle rule: %v", err)
-		}
-	}
-
-	if err := m.rConn.Flush(); err != nil {
-		return err
-	}
-
-	delete(m.rules, r.ID())
-	m.ipsetStore.DeleteReferenceFromIpSet(r.nftSet.Name)
-
-	if m.ipsetStore.HasReferenceToSet(r.nftSet.Name) {
-		return nil
-	}
-
-	// we delete last IP from the set, that means we need to delete
-	// set itself and associated firewall rule too
-	m.rConn.FlushSet(r.nftSet)
-	m.rConn.DelSet(r.nftSet)
-	m.ipsetStore.deleteIpset(r.nftSet.Name)
-	return nil
-}
-
-// createDefaultAllowRules creates default allow rules for the input and output chains
-func (m *AclManager) createDefaultAllowRules() error {
-	expIn := []expr.Any{
-		&expr.Verdict{
-			Kind: expr.VerdictAccept,
-		},
-	}
-
-	_ = m.rConn.InsertRule(&nftables.Rule{
-		Table:    m.workTable,
-		Chain:    m.chainInputRules,
-		Position: 0,
-		Exprs:    expIn,
-	})
-
-	if err := m.rConn.Flush(); err != nil {
-		return fmt.Errorf(flushError, err)
-	}
-	return nil
-}
-
-// Flush rule/chain/set operations from the buffer
-//
-// Method also get all rules after flush and refreshes handle values in the rulesets
-func (m *AclManager) Flush() error {
-	if err := m.flushWithBackoff(); err != nil {
-		return err
-	}
-
-	if err := m.refreshRuleHandles(m.chainInputRules, false); err != nil {
-		log.Errorf("failed to refresh rule handles ipv4 input chain: %v", err)
-	}
-	if err := m.refreshRuleHandles(m.chainPrerouting, true); err != nil {
-		log.Errorf("failed to refresh rule handles prerouting chain: %v", err)
-	}
-
-	return nil
-}
-
-func (m *AclManager) addIOFiltering(
-	ip net.IP,
-	proto firewall.Protocol,
-	sPort *firewall.Port,
-	dPort *firewall.Port,
-	action firewall.Action,
-	ipset *nftables.Set,
-) (*Rule, error) {
-	ruleId := generatePeerRuleId(ip, proto, sPort, dPort, action, ipset)
-	if r, ok := m.rules[ruleId]; ok {
-		return &Rule{
-			nftRule:    r.nftRule,
-			mangleRule: r.mangleRule,
-			nftSet:     r.nftSet,
-			ruleID:     r.ruleID,
-			ip:         ip,
-		}, nil
-	}
-
-	var expressions []expr.Any
-
-	if proto != firewall.ProtocolALL {
-		expressions = append(expressions, &expr.Payload{
-			DestRegister: 1,
-			Base:         expr.PayloadBaseNetworkHeader,
-			Offset:       m.af.protoOffset,
-			Len:          uint32(1),
-		})
-
-		protoData, err := m.af.protoNum(proto)
-		if err != nil {
-			return nil, fmt.Errorf("convert protocol to number: %v", err)
-		}
-
-		expressions = append(expressions, &expr.Cmp{
-			Register: 1,
-			Op:       expr.CmpOpEq,
-			Data:     []byte{protoData},
-		})
-	}
-
-	rawIP := ipToBytes(ip, m.af)
-	// check if rawIP contains zeroed IPv4 0.0.0.0 value
-	// in that case not add IP match expression into the rule definition
-	if slices.ContainsFunc(rawIP, func(v byte) bool { return v != 0 }) {
-		expressions = append(expressions,
-			&expr.Payload{
-				DestRegister: 1,
-				Base:         expr.PayloadBaseNetworkHeader,
-				Offset:       m.af.srcAddrOffset,
-				Len:          m.af.addrLen,
-			},
-		)
-		// add individual IP for match if no ipset defined
-		if ipset == nil {
-			expressions = append(expressions,
-				&expr.Cmp{
-					Op:       expr.CmpOpEq,
-					Register: 1,
-					Data:     rawIP,
-				},
-			)
-		} else {
-			expressions = append(expressions,
-				&expr.Lookup{
-					SourceRegister: 1,
-					SetName:        ipset.Name,
-					SetID:          ipset.ID,
-				},
-			)
-		}
-	}
-
-	expressions = append(expressions, applyPort(sPort, true)...)
-	expressions = append(expressions, applyPort(dPort, false)...)
-
-	mainExpressions := slices.Clone(expressions)
-
-	switch action {
-	case firewall.ActionAccept:
-		mainExpressions = append(mainExpressions, &expr.Verdict{Kind: expr.VerdictAccept})
-	case firewall.ActionDrop:
-		mainExpressions = append(mainExpressions, &expr.Verdict{Kind: expr.VerdictDrop})
-	}
-
-	userData := []byte(ruleId)
-
-	chain := m.chainInputRules
-	rule := &nftables.Rule{
-		Table:    m.workTable,
-		Chain:    chain,
-		Exprs:    mainExpressions,
-		UserData: userData,
-	}
-
-	// Insert DROP rules at the beginning, append ACCEPT rules at the end
-	var nftRule *nftables.Rule
-	if action == firewall.ActionDrop {
-		nftRule = m.rConn.InsertRule(rule)
-	} else {
-		nftRule = m.rConn.AddRule(rule)
-	}
-
-	if err := m.rConn.Flush(); err != nil {
-		return nil, fmt.Errorf("flush input rule %s: %v", ruleId, err)
-	}
-
-	ruleStruct := &Rule{
-		nftRule: nftRule,
-		// best effort mangle rule
-		mangleRule: m.createPreroutingRule(expressions, userData),
-		nftSet:     ipset,
-		ruleID:     ruleId,
-		ip:         ip,
-	}
-	m.rules[ruleId] = ruleStruct
-	if ipset != nil {
-		m.ipsetStore.AddReferenceToIpset(ipset.Name)
-	}
-
-	return ruleStruct, nil
-}
-
-func (m *AclManager) createPreroutingRule(expressions []expr.Any, userData []byte) *nftables.Rule {
-	if m.chainPrerouting == nil {
-		log.Warn("prerouting chain is not created")
-		return nil
-	}
-
-	preroutingExprs := slices.Clone(expressions)
-
-	// interface
-	preroutingExprs = append([]expr.Any{
-		&expr.Meta{
-			Key:      expr.MetaKeyIIFNAME,
-			Register: 1,
-		},
-		&expr.Cmp{
-			Op:       expr.CmpOpEq,
-			Register: 1,
-			Data:     ifname(m.wgIface.Name()),
-		},
-	}, preroutingExprs...)
-
-	// local destination and mark
-	preroutingExprs = append(preroutingExprs,
-		&expr.Fib{
-			Register:       1,
-			ResultADDRTYPE: true,
-			FlagDADDR:      true,
-		},
-		&expr.Cmp{
-			Op:       expr.CmpOpEq,
-			Register: 1,
-			Data:     binaryutil.NativeEndian.PutUint32(unix.RTN_LOCAL),
-		},
-
-		&expr.Immediate{
-			Register: 1,
-			Data:     binaryutil.NativeEndian.PutUint32(nbnet.PreroutingFwmarkRedirected),
-		},
-		&expr.Meta{
-			Key:            expr.MetaKeyMARK,
-			Register:       1,
-			SourceRegister: true,
-		},
-	)
-
-	nfRule := m.rConn.AddRule(&nftables.Rule{
-		Table:    m.workTable,
-		Chain:    m.chainPrerouting,
-		Exprs:    preroutingExprs,
-		UserData: userData,
-	})
-
-	if err := m.rConn.Flush(); err != nil {
-		log.Errorf("failed to flush mangle rule %s: %v", string(userData), err)
-		return nil
-	}
-
-	return nfRule
-}
-
-func (m *AclManager) createDefaultChains() (err error) {
-	// chainNameInputRules
-	chain := m.createChain(chainNameInputRules)
-	err = m.rConn.Flush()
-	if err != nil {
-		log.Debugf("failed to create chain (%s): %s", chain.Name, err)
-		return fmt.Errorf(flushError, err)
-	}
-	m.chainInputRules = chain
-
-	// netbird-acl-input-filter
-	// type filter hook input priority filter; policy accept;
-	chain = m.createFilterChainWithHook(chainNameInputFilter, nftables.ChainHookInput)
-	m.addJumpRule(chain, m.chainInputRules.Name, expr.MetaKeyIIFNAME) // to netbird-acl-input-rules
-	m.addDropExpressions(chain, expr.MetaKeyIIFNAME)
-	err = m.rConn.Flush()
-	if err != nil {
-		log.Debugf("failed to create chain (%s): %s", chain.Name, err)
-		return err
-	}
-
-	// netbird-acl-forward-filter
-	chainFwFilter := m.createFilterChainWithHook(chainNameForwardFilter, nftables.ChainHookForward)
-	m.addJumpRulesToRtForward(chainFwFilter) // to netbird-rt-fwd
-	m.addDropExpressions(chainFwFilter, expr.MetaKeyIIFNAME)
-
-	err = m.rConn.Flush()
-	if err != nil {
-		log.Debugf("failed to create chain (%s): %s", chainNameForwardFilter, err)
-		return fmt.Errorf(flushError, err)
-	}
-
-	if err := m.allowRedirectedTraffic(chainFwFilter); err != nil {
-		log.Errorf("failed to allow redirected traffic: %s", err)
-	}
-
-	return nil
-}
-
-// Makes redirected traffic originally destined for the host itself (now subject to the forward filter)
-// go through the input filter as well. This will enable e.g. Docker services to keep working by accessing the
-// netbird peer IP.
-func (m *AclManager) allowRedirectedTraffic(chainFwFilter *nftables.Chain) error {
-	// Chain is created by route manager
-	// TODO: move creation to a common place
-	m.chainPrerouting = &nftables.Chain{
-		Name:     chainNameManglePrerouting,
-		Table:    m.workTable,
-		Type:     nftables.ChainTypeFilter,
-		Hooknum:  nftables.ChainHookPrerouting,
-		Priority: nftables.ChainPriorityMangle,
-	}
-
-	m.addFwmarkToForward(chainFwFilter)
-
-	if err := m.rConn.Flush(); err != nil {
-		return fmt.Errorf(flushError, err)
-	}
-
-	return nil
-}
-
-func (m *AclManager) addFwmarkToForward(chainFwFilter *nftables.Chain) {
-	m.rConn.InsertRule(&nftables.Rule{
-		Table: m.workTable,
-		Chain: chainFwFilter,
-		Exprs: []expr.Any{
-			&expr.Meta{
-				Key:      expr.MetaKeyMARK,
-				Register: 1,
-			},
-			&expr.Cmp{
-				Op:       expr.CmpOpEq,
-				Register: 1,
-				Data:     binaryutil.NativeEndian.PutUint32(nbnet.PreroutingFwmarkRedirected),
-			},
-			&expr.Verdict{
-				Kind: expr.VerdictAccept,
-			},
-		},
-	})
-}
-
-func (m *AclManager) addJumpRulesToRtForward(chainFwFilter *nftables.Chain) {
-	expressions := []expr.Any{
-		&expr.Meta{Key: expr.MetaKeyIIFNAME, Register: 1},
-		&expr.Cmp{
-			Op:       expr.CmpOpEq,
-			Register: 1,
-			Data:     ifname(m.wgIface.Name()),
-		},
-		&expr.Verdict{
-			Kind:  expr.VerdictJump,
-			Chain: m.routingFwChainName,
-		},
-	}
-
-	_ = m.rConn.AddRule(&nftables.Rule{
-		Table: m.workTable,
-		Chain: chainFwFilter,
-		Exprs: expressions,
-	})
-}
-
-func (m *AclManager) createChain(name string) *nftables.Chain {
-	chain := &nftables.Chain{
-		Name:  name,
-		Table: m.workTable,
-	}
-
-	chain = m.rConn.AddChain(chain)
-
-	insertReturnTrafficRule(m.rConn, m.workTable, chain)
-
-	return chain
-}
-
-func (m *AclManager) createFilterChainWithHook(name string, hookNum *nftables.ChainHook) *nftables.Chain {
-	polAccept := nftables.ChainPolicyAccept
-	chain := &nftables.Chain{
-		Name:     name,
-		Table:    m.workTable,
-		Hooknum:  hookNum,
-		Priority: nftables.ChainPriorityFilter,
-		Type:     nftables.ChainTypeFilter,
-		Policy:   &polAccept,
-	}
-
-	return m.rConn.AddChain(chain)
-}
-
-func (m *AclManager) addDropExpressions(chain *nftables.Chain, ifaceKey expr.MetaKey) []expr.Any {
-	expressions := []expr.Any{
-		&expr.Meta{Key: ifaceKey, Register: 1},
-		&expr.Cmp{
-			Op:       expr.CmpOpEq,
-			Register: 1,
-			Data:     ifname(m.wgIface.Name()),
-		},
-		&expr.Verdict{Kind: expr.VerdictDrop},
-	}
-	_ = m.rConn.AddRule(&nftables.Rule{
-		Table: m.workTable,
-		Chain: chain,
-		Exprs: expressions,
-	})
-	return nil
-}
-
-func (m *AclManager) addJumpRule(chain *nftables.Chain, to string, ifaceKey expr.MetaKey) {
-	expressions := []expr.Any{
-		&expr.Meta{Key: ifaceKey, Register: 1},
-		&expr.Cmp{
-			Op:       expr.CmpOpEq,
-			Register: 1,
-			Data:     ifname(m.wgIface.Name()),
-		},
-		&expr.Verdict{
-			Kind:  expr.VerdictJump,
-			Chain: to,
-		},
-	}
-
-	_ = m.rConn.AddRule(&nftables.Rule{
-		Table: chain.Table,
-		Chain: chain,
-		Exprs: expressions,
-	})
-}
-
-func (m *AclManager) addIpToSet(ipsetName string, ip net.IP) (*nftables.Set, error) {
-	ipset, err := m.rConn.GetSetByName(m.workTable, ipsetName)
-	rawIP := ipToBytes(ip, m.af)
-	if err != nil {
-		if ipset, err = m.createSet(m.workTable, ipsetName); err != nil {
-			return nil, fmt.Errorf("get set name: %v", err)
-		}
-
-		m.ipsetStore.newIpset(ipset.Name)
-	}
-
-	if m.ipsetStore.IsIpInSet(ipset.Name, ip) {
-		return ipset, nil
-	}
-
-	if err := m.sConn.SetAddElements(ipset, []nftables.SetElement{{Key: rawIP}}); err != nil {
-		return nil, fmt.Errorf("add set element for the first time: %v", err)
-	}
-
-	m.ipsetStore.AddIpToSet(ipset.Name, ip)
-
-	if err := m.sConn.Flush(); err != nil {
-		return nil, fmt.Errorf("flush add elements: %v", err)
-	}
-
-	return ipset, nil
-}
-
-// createSet in given table by name
-func (m *AclManager) createSet(table *nftables.Table, name string) (*nftables.Set, error) {
-	ipset := &nftables.Set{
-		Name:    name,
-		Table:   table,
-		Dynamic: true,
-		KeyType: m.af.setKeyType,
-	}
-
-	if err := m.rConn.AddSet(ipset, nil); err != nil {
-		return nil, fmt.Errorf("create set: %v", err)
-	}
-
-	if err := m.rConn.Flush(); err != nil {
-		return nil, fmt.Errorf("flush created set: %v", err)
-	}
-
-	return ipset, nil
-}
-
-func (m *AclManager) flushWithBackoff() (err error) {
-	backoff := 4
-	backoffTime := 1000 * time.Millisecond
-	for i := 0; ; i++ {
-		err = m.rConn.Flush()
-		if err != nil {
-			log.Debugf("failed to flush nftables: %v", err)
-			if !strings.Contains(err.Error(), "busy") {
-				return
-			}
-			log.Error("failed to flush nftables, retrying...")
-			if i == backoff-1 {
-				return err
-			}
-			time.Sleep(backoffTime)
-			backoffTime *= 2
-			continue
-		}
-		break
-	}
-	return
-}
-
-func (m *AclManager) refreshRuleHandles(chain *nftables.Chain, mangle bool) error {
-	if m.workTable == nil || chain == nil {
-		return nil
-	}
-
-	list, err := m.rConn.GetRules(m.workTable, chain)
-	if err != nil {
-		return err
-	}
-
-	for _, rule := range list {
-		if len(rule.UserData) == 0 {
-			continue
-		}
-		split := bytes.Split(rule.UserData, []byte(" "))
-		r, ok := m.rules[string(split[0])]
-		if ok {
-			if mangle {
-				*r.mangleRule = *rule
-			} else {
-				*r.nftRule = *rule
-			}
-		}
-	}
-
-	return nil
-}
-
-func generatePeerRuleId(ip net.IP, proto firewall.Protocol, sPort *firewall.Port, dPort *firewall.Port, action firewall.Action, ipset *nftables.Set) string {
-	rulesetID := ":" + string(proto) + ":"
-	if sPort != nil {
-		rulesetID += sPort.String()
-	}
-	rulesetID += ":"
-	if dPort != nil {
-		rulesetID += dPort.String()
-	}
-	rulesetID += ":"
-	rulesetID += strconv.Itoa(int(action))
-	if ipset == nil {
-		return "ip:" + ip.String() + rulesetID
-	}
-	return "set:" + ipset.Name + rulesetID
-}
-
-func ifname(n string) []byte {
-	b := make([]byte, 16)
-	copy(b, n+"\x00")
-	return b
-}
-
-
-// ipToBytes converts net.IP to the correct byte length for the address family.
-func ipToBytes(ip net.IP, af addrFamily) []byte {
-	if af.addrLen == 4 {
-		return ip.To4()
-	}
-	return ip.To16()
-}
-

client/firewall/nftables/chains_linux.go

@@ -0,0 +1,890 @@
+//go:build !android
+
+package nftables
+
+import (
+	"bytes"
+	"errors"
+	"fmt"
+	"slices"
+	"strings"
+	"time"
+
+	"github.com/coreos/go-iptables/iptables"
+	"github.com/google/nftables"
+	"github.com/google/nftables/binaryutil"
+	"github.com/google/nftables/expr"
+	"github.com/hashicorp/go-multierror"
+	log "github.com/sirupsen/logrus"
+	"golang.org/x/sys/unix"
+
+	nberrors "github.com/netbirdio/netbird/client/errors"
+	"github.com/netbirdio/netbird/client/firewall/firewalld"
+	firewall "github.com/netbirdio/netbird/client/firewall/manager"
+	nbnet "github.com/netbirdio/netbird/client/net"
+)
+
+func (r *family) createContainers() error {
+	r.chains[chainNameRoutingFw] = r.conn.AddChain(&nftables.Chain{
+		Name:  chainNameRoutingFw,
+		Table: r.workTable,
+	})
+
+	prio := *nftables.ChainPriorityNATSource - 1
+	r.chains[chainNameRoutingNat] = r.conn.AddChain(&nftables.Chain{
+		Name:     chainNameRoutingNat,
+		Table:    r.workTable,
+		Hooknum:  nftables.ChainHookPostrouting,
+		Priority: &prio,
+		Type:     nftables.ChainTypeNAT,
+	})
+
+	r.chains[chainNameRoutingRdr] = r.conn.AddChain(&nftables.Chain{
+		Name:     chainNameRoutingRdr,
+		Table:    r.workTable,
+		Hooknum:  nftables.ChainHookPrerouting,
+		Priority: nftables.ChainPriorityNATDest,
+		Type:     nftables.ChainTypeNAT,
+	})
+
+	r.chains[chainNameManglePostrouting] = r.conn.AddChain(&nftables.Chain{
+		Name:     chainNameManglePostrouting,
+		Table:    r.workTable,
+		Hooknum:  nftables.ChainHookPostrouting,
+		Priority: nftables.ChainPriorityMangle,
+		Type:     nftables.ChainTypeFilter,
+	})
+
+	r.chains[chainNameManglePrerouting] = r.conn.AddChain(&nftables.Chain{
+		Name:     chainNameManglePrerouting,
+		Table:    r.workTable,
+		Hooknum:  nftables.ChainHookPrerouting,
+		Priority: nftables.ChainPriorityMangle,
+		Type:     nftables.ChainTypeFilter,
+	})
+
+	r.chains[chainNameMangleForward] = r.conn.AddChain(&nftables.Chain{
+		Name:     chainNameMangleForward,
+		Table:    r.workTable,
+		Hooknum:  nftables.ChainHookForward,
+		Priority: nftables.ChainPriorityMangle,
+		Type:     nftables.ChainTypeFilter,
+	})
+
+	insertReturnTrafficRule(r.conn, r.workTable, r.chains[chainNameRoutingFw])
+
+	r.addPostroutingRules()
+
+	if err := r.conn.Flush(); err != nil {
+		return fmt.Errorf("initialize tables: %v", err)
+	}
+
+	if err := r.addMSSClampingRules(); err != nil {
+		log.Errorf("failed to add MSS clamping rules: %s", err)
+	}
+
+	if err := r.acceptForwardRules(); err != nil {
+		log.Errorf("failed to add accept rules for the forward chain: %s", err)
+	}
+
+	if err := firewalld.TrustInterface(r.wgIface.Name()); err != nil {
+		log.Warnf("failed to trust interface in firewalld: %v", err)
+	}
+
+	if err := r.refreshRulesMap(); err != nil {
+		log.Errorf("failed to refresh rules: %s", err)
+	}
+
+	return nil
+}
+
+// setupDataPlaneMark configures the fwmark for the data plane
+func (r *family) setupDataPlaneMark() error {
+	if r.chains[chainNameManglePrerouting] == nil || r.chains[chainNameManglePostrouting] == nil {
+		return errors.New("no mangle chains found")
+	}
+
+	ctNew := getCtNewExprs()
+	preExprs := []expr.Any{
+		&expr.Meta{
+			Key:      expr.MetaKeyIIFNAME,
+			Register: 1,
+		},
+		&expr.Cmp{
+			Op:       expr.CmpOpEq,
+			Register: 1,
+			Data:     ifname(r.wgIface.Name()),
+		},
+	}
+	preExprs = append(preExprs, ctNew...)
+	preExprs = append(preExprs,
+		&expr.Immediate{
+			Register: 1,
+			Data:     binaryutil.NativeEndian.PutUint32(nbnet.DataPlaneMarkIn),
+		},
+		&expr.Ct{
+			Key:            expr.CtKeyMARK,
+			Register:       1,
+			SourceRegister: true,
+		},
+	)
+
+	preNftRule := &nftables.Rule{
+		Table: r.workTable,
+		Chain: r.chains[chainNameManglePrerouting],
+		Exprs: preExprs,
+	}
+	r.conn.AddRule(preNftRule)
+
+	postExprs := []expr.Any{
+		&expr.Meta{
+			Key:      expr.MetaKeyOIFNAME,
+			Register: 1,
+		},
+		&expr.Cmp{
+			Op:       expr.CmpOpEq,
+			Register: 1,
+			Data:     ifname(r.wgIface.Name()),
+		},
+	}
+	postExprs = append(postExprs, ctNew...)
+	postExprs = append(postExprs,
+		&expr.Immediate{
+			Register: 1,
+			Data:     binaryutil.NativeEndian.PutUint32(nbnet.DataPlaneMarkOut),
+		},
+		&expr.Ct{
+			Key:            expr.CtKeyMARK,
+			Register:       1,
+			SourceRegister: true,
+		},
+	)
+
+	postNftRule := &nftables.Rule{
+		Table: r.workTable,
+		Chain: r.chains[chainNameManglePostrouting],
+		Exprs: postExprs,
+	}
+	r.conn.AddRule(postNftRule)
+
+	if err := r.conn.Flush(); err != nil {
+		return fmt.Errorf("flush: %w", err)
+	}
+
+	return nil
+}
+
+func (r *family) acceptForwardRules() error {
+	var merr *multierror.Error
+
+	if err := r.acceptFilterTableRules(); err != nil {
+		merr = multierror.Append(merr, err)
+	}
+
+	if err := r.acceptExternalChainsRules(); err != nil {
+		merr = multierror.Append(merr, fmt.Errorf("add accept rules to external chains: %w", err))
+	}
+
+	return nberrors.FormatErrorOrNil(merr)
+}
+
+func (r *family) acceptFilterTableRules() error {
+	if r.filterTable == nil {
+		return nil
+	}
+
+	fw := "iptables"
+
+	defer func() {
+		log.Debugf("Used %s to add accept forward and input rules", fw)
+	}()
+
+	// Try iptables first and fallback to nftables if iptables is not available.
+	// Use the correct protocol (iptables vs ip6tables) for the address family.
+	ipt, err := iptables.NewWithProtocol(r.iptablesProto())
+	if err != nil {
+		log.Warnf("Will use nftables to manipulate the filter table because iptables is not available: %v", err)
+
+		fw = "nftables"
+		return r.acceptFilterRulesNftables(r.filterTable)
+	}
+
+	if err := r.acceptFilterRulesIptables(ipt); err != nil {
+		log.Warnf("iptables failed (table may be incompatible), falling back to nftables: %v", err)
+		fw = "nftables"
+		return r.acceptFilterRulesNftables(r.filterTable)
+	}
+	return nil
+}
+
+func (r *family) acceptFilterRulesIptables(ipt *iptables.IPTables) error {
+	var merr *multierror.Error
+
+	for _, rule := range r.getAcceptForwardRules() {
+		if err := ipt.Insert("filter", chainNameForward, 1, rule...); err != nil {
+			merr = multierror.Append(merr, fmt.Errorf("add iptables forward rule: %v", err))
+		} else {
+			log.Debugf("added iptables forward rule: %v", rule)
+		}
+	}
+
+	inputRule := r.getAcceptInputRule()
+	if err := ipt.Insert("filter", chainNameInput, 1, inputRule...); err != nil {
+		merr = multierror.Append(merr, fmt.Errorf("add iptables input rule: %v", err))
+	} else {
+		log.Debugf("added iptables input rule: %v", inputRule)
+	}
+
+	return nberrors.FormatErrorOrNil(merr)
+}
+
+func (r *family) getAcceptForwardRules() [][]string {
+	intf := r.wgIface.Name()
+	return [][]string{
+		{"-i", intf, "-j", "ACCEPT"},
+		{"-o", intf, "-m", "conntrack", "--ctstate", "RELATED,ESTABLISHED", "-j", "ACCEPT"},
+	}
+}
+
+func (r *family) getAcceptInputRule() []string {
+	return []string{"-i", r.wgIface.Name(), "-j", "ACCEPT"}
+}
+
+// acceptFilterRulesNftables adds accept rules to the ip filter table using nftables.
+// This is used when iptables is not available.
+func (r *family) acceptFilterRulesNftables(table *nftables.Table) error {
+	intf := ifname(r.wgIface.Name())
+
+	forwardChain := &nftables.Chain{
+		Name:     chainNameForward,
+		Table:    table,
+		Type:     nftables.ChainTypeFilter,
+		Hooknum:  nftables.ChainHookForward,
+		Priority: nftables.ChainPriorityFilter,
+	}
+	r.insertForwardAcceptRules(forwardChain, intf)
+
+	inputChain := &nftables.Chain{
+		Name:     chainNameInput,
+		Table:    table,
+		Type:     nftables.ChainTypeFilter,
+		Hooknum:  nftables.ChainHookInput,
+		Priority: nftables.ChainPriorityFilter,
+	}
+	r.insertInputAcceptRule(inputChain, intf)
+
+	return r.conn.Flush()
+}
+
+// acceptExternalChainsRules adds accept rules to external chains (non-netbird, non-iptables tables).
+// It dynamically finds chains at call time to handle chains that may have been created after startup.
+func (r *family) acceptExternalChainsRules() error {
+	chains := r.findExternalChains()
+	if len(chains) == 0 {
+		return nil
+	}
+
+	intf := ifname(r.wgIface.Name())
+	for _, chain := range chains {
+		r.applyExternalChainAccept(chain, intf)
+	}
+
+	if err := r.conn.Flush(); err != nil {
+		return fmt.Errorf("flush external chain rules: %w", err)
+	}
+	return nil
+}
+
+func (r *family) applyExternalChainAccept(chain *nftables.Chain, intf []byte) {
+	if chain.Hooknum == nil {
+		log.Debugf("skipping external chain %s/%s: hooknum is nil", chain.Table.Name, chain.Name)
+		return
+	}
+
+	log.Debugf("adding accept rules to external %s chain: %s %s/%s",
+		hookName(chain.Hooknum), familyName(chain.Table.Family), chain.Table.Name, chain.Name)
+
+	switch *chain.Hooknum {
+	case *nftables.ChainHookForward:
+		r.insertForwardAcceptRules(chain, intf)
+	case *nftables.ChainHookInput:
+		r.insertInputAcceptRule(chain, intf)
+	}
+}
+
+func (r *family) insertForwardAcceptRules(chain *nftables.Chain, intf []byte) {
+	existing, err := r.existingNetbirdRulesInChain(chain)
+	if err != nil {
+		log.Warnf("skip forward accept rules in %s/%s: %v", chain.Table.Name, chain.Name, err)
+		return
+	}
+	r.insertForwardIifRule(chain, intf, existing)
+	r.insertForwardOifEstablishedRule(chain, intf, existing)
+}
+
+func (r *family) insertForwardIifRule(chain *nftables.Chain, intf []byte, existing map[string]bool) {
+	if existing[userDataAcceptForwardRuleIif] {
+		return
+	}
+	r.conn.InsertRule(&nftables.Rule{
+		Table: chain.Table,
+		Chain: chain,
+		Exprs: []expr.Any{
+			&expr.Meta{Key: expr.MetaKeyIIFNAME, Register: 1},
+			&expr.Cmp{Op: expr.CmpOpEq, Register: 1, Data: intf},
+			&expr.Counter{},
+			&expr.Verdict{Kind: expr.VerdictAccept},
+		},
+		UserData: []byte(userDataAcceptForwardRuleIif),
+	})
+}
+
+func (r *family) insertForwardOifEstablishedRule(chain *nftables.Chain, intf []byte, existing map[string]bool) {
+	if existing[userDataAcceptForwardRuleOif] {
+		return
+	}
+	exprs := []expr.Any{
+		&expr.Meta{Key: expr.MetaKeyOIFNAME, Register: 1},
+		&expr.Cmp{Op: expr.CmpOpEq, Register: 1, Data: intf},
+	}
+	r.conn.InsertRule(&nftables.Rule{
+		Table:    chain.Table,
+		Chain:    chain,
+		Exprs:    append(exprs, getEstablishedExprs(2)...),
+		UserData: []byte(userDataAcceptForwardRuleOif),
+	})
+}
+
+func (r *family) insertInputAcceptRule(chain *nftables.Chain, intf []byte) {
+	existing, err := r.existingNetbirdRulesInChain(chain)
+	if err != nil {
+		log.Warnf("skip input accept rule in %s/%s: %v", chain.Table.Name, chain.Name, err)
+		return
+	}
+	if existing[userDataAcceptInputRule] {
+		return
+	}
+	r.conn.InsertRule(&nftables.Rule{
+		Table: chain.Table,
+		Chain: chain,
+		Exprs: []expr.Any{
+			&expr.Meta{Key: expr.MetaKeyIIFNAME, Register: 1},
+			&expr.Cmp{Op: expr.CmpOpEq, Register: 1, Data: intf},
+			&expr.Counter{},
+			&expr.Verdict{Kind: expr.VerdictAccept},
+		},
+		UserData: []byte(userDataAcceptInputRule),
+	})
+}
+
+// existingNetbirdRulesInChain returns the set of netbird-owned UserData tags present in a chain; callers must bail on error since InsertRule is additive.
+func (r *family) existingNetbirdRulesInChain(chain *nftables.Chain) (map[string]bool, error) {
+	rules, err := r.conn.GetRules(chain.Table, chain)
+	if err != nil {
+		return nil, fmt.Errorf("list rules: %w", err)
+	}
+	present := map[string]bool{}
+	for _, rule := range rules {
+		if !isNetbirdAcceptRuleTag(rule.UserData) {
+			continue
+		}
+		present[string(rule.UserData)] = true
+	}
+	return present, nil
+}
+
+func isNetbirdAcceptRuleTag(userData []byte) bool {
+	switch string(userData) {
+	case userDataAcceptForwardRuleIif,
+		userDataAcceptForwardRuleOif,
+		userDataAcceptInputRule:
+		return true
+	}
+	return false
+}
+
+func (r *family) removeAcceptFilterRules() error {
+	var merr *multierror.Error
+
+	if err := r.removeFilterTableRules(); err != nil {
+		merr = multierror.Append(merr, err)
+	}
+
+	if err := r.removeExternalChainsRules(); err != nil {
+		merr = multierror.Append(merr, fmt.Errorf("remove external chain rules: %w", err))
+	}
+
+	return nberrors.FormatErrorOrNil(merr)
+}
+
+func (r *family) removeFilterTableRules() error {
+	if r.filterTable == nil {
+		return nil
+	}
+
+	ipt, err := iptables.NewWithProtocol(r.iptablesProto())
+	if err != nil {
+		log.Debugf("iptables not available, using nftables to remove filter rules: %v", err)
+		return r.removeAcceptRulesFromTable(r.filterTable)
+	}
+
+	if err := r.removeAcceptFilterRulesIptables(ipt); err != nil {
+		log.Debugf("iptables removal failed (table may be incompatible), falling back to nftables: %v", err)
+		return r.removeAcceptRulesFromTable(r.filterTable)
+	}
+	return nil
+}
+
+func (r *family) removeAcceptRulesFromTable(table *nftables.Table) error {
+	chains, err := r.conn.ListChainsOfTableFamily(table.Family)
+	if err != nil {
+		return fmt.Errorf("list chains: %v", err)
+	}
+
+	for _, chain := range chains {
+		if chain.Table.Name != table.Name {
+			continue
+		}
+
+		if chain.Name != chainNameForward && chain.Name != chainNameInput {
+			continue
+		}
+
+		if err := r.removeAcceptRulesFromChain(table, chain); err != nil {
+			return err
+		}
+	}
+
+	return r.conn.Flush()
+}
+
+func (r *family) removeAcceptRulesFromChain(table *nftables.Table, chain *nftables.Chain) error {
+	rules, err := r.conn.GetRules(table, chain)
+	if err != nil {
+		return fmt.Errorf("get rules from %s/%s: %v", table.Name, chain.Name, err)
+	}
+
+	for _, rule := range rules {
+		if bytes.Equal(rule.UserData, []byte(userDataAcceptForwardRuleIif)) ||
+			bytes.Equal(rule.UserData, []byte(userDataAcceptForwardRuleOif)) ||
+			bytes.Equal(rule.UserData, []byte(userDataAcceptInputRule)) {
+			if err := r.conn.DelRule(rule); err != nil {
+				return fmt.Errorf("delete rule from %s/%s: %v", table.Name, chain.Name, err)
+			}
+		}
+	}
+	return nil
+}
+
+// removeExternalChainsRules removes our accept rules from all external chains.
+// This is deterministic - it scans for chains at removal time rather than relying on saved state,
+// ensuring cleanup works even after a crash or if chains changed.
+func (r *family) removeExternalChainsRules() error {
+	chains := r.findExternalChains()
+	if len(chains) == 0 {
+		return nil
+	}
+
+	var merr *multierror.Error
+	for _, chain := range chains {
+		if err := r.removeAcceptRulesFromChain(chain.Table, chain); err != nil {
+			merr = multierror.Append(merr, fmt.Errorf("remove rules from external chain %s/%s: %w", chain.Table.Name, chain.Name, err))
+			continue
+		}
+		if err := r.conn.Flush(); err != nil {
+			merr = multierror.Append(merr, fmt.Errorf("flush external chain %s/%s: %w", chain.Table.Name, chain.Name, err))
+		}
+	}
+
+	return nberrors.FormatErrorOrNil(merr)
+}
+
+// findExternalChains scans for chains from non-netbird tables that have FORWARD or INPUT hooks.
+// This is used both at startup (to know where to add rules) and at cleanup (to ensure deterministic removal).
+func (r *family) findExternalChains() []*nftables.Chain {
+	var chains []*nftables.Chain
+
+	families := []nftables.TableFamily{r.af.tableFamily, nftables.TableFamilyINet}
+
+	for _, family := range families {
+		allChains, err := r.conn.ListChainsOfTableFamily(family)
+		if err != nil {
+			log.Debugf("list chains for family %d: %v", family, err)
+			continue
+		}
+
+		for _, chain := range allChains {
+			if r.isExternalChain(chain) {
+				chains = append(chains, chain)
+			}
+		}
+	}
+
+	return chains
+}
+
+func (r *family) isExternalChain(chain *nftables.Chain) bool {
+	if r.workTable != nil && chain.Table.Name == r.workTable.Name {
+		return false
+	}
+
+	// Skip firewalld-owned chains. Firewalld creates its chains with the
+	// NFT_CHAIN_OWNER flag, so inserting rules into them returns EPERM.
+	// We delegate acceptance to firewalld by trusting the interface instead.
+	if chain.Table.Name == firewalldTableName {
+		return false
+	}
+
+	// Skip iptables/ip6tables-managed tables (adding nft-native rules breaks iptables-save compat)
+	if (chain.Table.Family == nftables.TableFamilyIPv4 || chain.Table.Family == nftables.TableFamilyIPv6) && isIptablesTable(chain.Table.Name) {
+		return false
+	}
+
+	if chain.Type != nftables.ChainTypeFilter {
+		return false
+	}
+
+	if chain.Hooknum == nil {
+		return false
+	}
+
+	return *chain.Hooknum == *nftables.ChainHookForward || *chain.Hooknum == *nftables.ChainHookInput
+}
+
+func isIptablesTable(name string) bool {
+	switch name {
+	case tableNameFilter, tableNat, tableMangle, tableRaw, tableSecurity:
+		return true
+	}
+	return false
+}
+
+func (r *family) removeAcceptFilterRulesIptables(ipt *iptables.IPTables) error {
+	var merr *multierror.Error
+
+	for _, rule := range r.getAcceptForwardRules() {
+		if err := ipt.DeleteIfExists("filter", chainNameForward, rule...); err != nil {
+			merr = multierror.Append(merr, fmt.Errorf("remove iptables forward rule: %v", err))
+		}
+	}
+
+	inputRule := r.getAcceptInputRule()
+	if err := ipt.DeleteIfExists("filter", chainNameInput, inputRule...); err != nil {
+		merr = multierror.Append(merr, fmt.Errorf("remove iptables input rule: %v", err))
+	}
+
+	return nberrors.FormatErrorOrNil(merr)
+}
+
+func (r *family) createDefaultAllowRules() error {
+	expIn := []expr.Any{
+		&expr.Verdict{
+			Kind: expr.VerdictAccept,
+		},
+	}
+
+	_ = r.conn.InsertRule(&nftables.Rule{
+		Table:    r.workTable,
+		Chain:    r.chainInputRules,
+		Position: 0,
+		Exprs:    expIn,
+	})
+
+	if err := r.conn.Flush(); err != nil {
+		return fmt.Errorf(flushError, err)
+	}
+	return nil
+}
+
+// Flush rule/chain/set operations from the buffer
+//
+// Method also get all rules after flush and refreshes handle values in the rulesets
+func (r *family) Flush() error {
+	if err := r.flushWithBackoff(); err != nil {
+		return err
+	}
+
+	if err := r.refreshRuleHandles(r.chainInputRules, false); err != nil {
+		log.Errorf("failed to refresh rule handles ipv4 input chain: %v", err)
+	}
+	if err := r.refreshRuleHandles(r.chainPrerouting, true); err != nil {
+		log.Errorf("failed to refresh rule handles prerouting chain: %v", err)
+	}
+
+	return nil
+}
+
+func (r *family) createPreroutingRule(expressions []expr.Any, userData []byte) *nftables.Rule {
+	if r.chainPrerouting == nil {
+		log.Warn("prerouting chain is not created")
+		return nil
+	}
+
+	preroutingExprs := slices.Clone(expressions)
+
+	// interface
+	preroutingExprs = append([]expr.Any{
+		&expr.Meta{
+			Key:      expr.MetaKeyIIFNAME,
+			Register: 1,
+		},
+		&expr.Cmp{
+			Op:       expr.CmpOpEq,
+			Register: 1,
+			Data:     ifname(r.wgIface.Name()),
+		},
+	}, preroutingExprs...)
+
+	// local destination and mark
+	preroutingExprs = append(preroutingExprs,
+		&expr.Fib{
+			Register:       1,
+			ResultADDRTYPE: true,
+			FlagDADDR:      true,
+		},
+		&expr.Cmp{
+			Op:       expr.CmpOpEq,
+			Register: 1,
+			Data:     binaryutil.NativeEndian.PutUint32(unix.RTN_LOCAL),
+		},
+
+		&expr.Immediate{
+			Register: 1,
+			Data:     binaryutil.NativeEndian.PutUint32(nbnet.PreroutingFwmarkRedirected),
+		},
+		&expr.Meta{
+			Key:            expr.MetaKeyMARK,
+			Register:       1,
+			SourceRegister: true,
+		},
+	)
+
+	nfRule := r.conn.AddRule(&nftables.Rule{
+		Table:    r.workTable,
+		Chain:    r.chainPrerouting,
+		Exprs:    preroutingExprs,
+		UserData: userData,
+	})
+
+	if err := r.conn.Flush(); err != nil {
+		log.Errorf("failed to flush mangle rule %s: %v", string(userData), err)
+		return nil
+	}
+
+	return nfRule
+}
+
+func (r *family) createDefaultChains() (err error) {
+	// chainNameInputRules
+	chain := r.createChain(chainNameInputRules)
+	err = r.conn.Flush()
+	if err != nil {
+		log.Debugf("failed to create chain (%s): %s", chain.Name, err)
+		return fmt.Errorf(flushError, err)
+	}
+	r.chainInputRules = chain
+
+	// netbird-acl-input-filter
+	// type filter hook input priority filter; policy accept;
+	chain = r.createFilterChainWithHook(chainNameInputFilter, nftables.ChainHookInput)
+	r.addJumpRule(chain, r.chainInputRules.Name, expr.MetaKeyIIFNAME) // to netbird-acl-input-rules
+	r.addDropExpressions(chain, expr.MetaKeyIIFNAME)
+	err = r.conn.Flush()
+	if err != nil {
+		log.Debugf("failed to create chain (%s): %s", chain.Name, err)
+		return err
+	}
+
+	// netbird-acl-forward-filter
+	chainFwFilter := r.createFilterChainWithHook(chainNameForwardFilter, nftables.ChainHookForward)
+	r.addJumpRulesToRtForward(chainFwFilter) // to netbird-rt-fwd
+	r.addDropExpressions(chainFwFilter, expr.MetaKeyIIFNAME)
+
+	err = r.conn.Flush()
+	if err != nil {
+		log.Debugf("failed to create chain (%s): %s", chainNameForwardFilter, err)
+		return fmt.Errorf(flushError, err)
+	}
+
+	if err := r.allowRedirectedTraffic(chainFwFilter); err != nil {
+		log.Errorf("failed to allow redirected traffic: %s", err)
+	}
+
+	return nil
+}
+
+// Makes redirected traffic originally destined for the host itself (now subject to the forward filter)
+// go through the input filter as well. This will enable e.g. Docker services to keep working by accessing the
+// netbird peer IP.
+func (r *family) allowRedirectedTraffic(chainFwFilter *nftables.Chain) error {
+	r.chainPrerouting = r.chains[chainNameManglePrerouting]
+
+	r.addFwmarkToForward(chainFwFilter)
+
+	if err := r.conn.Flush(); err != nil {
+		return fmt.Errorf(flushError, err)
+	}
+
+	return nil
+}
+
+func (r *family) addFwmarkToForward(chainFwFilter *nftables.Chain) {
+	r.conn.InsertRule(&nftables.Rule{
+		Table: r.workTable,
+		Chain: chainFwFilter,
+		Exprs: []expr.Any{
+			&expr.Meta{
+				Key:      expr.MetaKeyMARK,
+				Register: 1,
+			},
+			&expr.Cmp{
+				Op:       expr.CmpOpEq,
+				Register: 1,
+				Data:     binaryutil.NativeEndian.PutUint32(nbnet.PreroutingFwmarkRedirected),
+			},
+			&expr.Verdict{
+				Kind: expr.VerdictAccept,
+			},
+		},
+	})
+}
+
+func (r *family) addJumpRulesToRtForward(chainFwFilter *nftables.Chain) {
+	expressions := []expr.Any{
+		&expr.Meta{Key: expr.MetaKeyIIFNAME, Register: 1},
+		&expr.Cmp{
+			Op:       expr.CmpOpEq,
+			Register: 1,
+			Data:     ifname(r.wgIface.Name()),
+		},
+		&expr.Verdict{
+			Kind:  expr.VerdictJump,
+			Chain: r.routingFwChainName,
+		},
+	}
+
+	_ = r.conn.AddRule(&nftables.Rule{
+		Table: r.workTable,
+		Chain: chainFwFilter,
+		Exprs: expressions,
+	})
+}
+
+func (r *family) createChain(name string) *nftables.Chain {
+	chain := &nftables.Chain{
+		Name:  name,
+		Table: r.workTable,
+	}
+
+	chain = r.conn.AddChain(chain)
+
+	insertReturnTrafficRule(r.conn, r.workTable, chain)
+
+	return chain
+}
+
+func (r *family) createFilterChainWithHook(name string, hookNum *nftables.ChainHook) *nftables.Chain {
+	polAccept := nftables.ChainPolicyAccept
+	chain := &nftables.Chain{
+		Name:     name,
+		Table:    r.workTable,
+		Hooknum:  hookNum,
+		Priority: nftables.ChainPriorityFilter,
+		Type:     nftables.ChainTypeFilter,
+		Policy:   &polAccept,
+	}
+
+	return r.conn.AddChain(chain)
+}
+
+func (r *family) addDropExpressions(chain *nftables.Chain, ifaceKey expr.MetaKey) []expr.Any {
+	expressions := []expr.Any{
+		&expr.Meta{Key: ifaceKey, Register: 1},
+		&expr.Cmp{
+			Op:       expr.CmpOpEq,
+			Register: 1,
+			Data:     ifname(r.wgIface.Name()),
+		},
+		&expr.Verdict{Kind: expr.VerdictDrop},
+	}
+	_ = r.conn.AddRule(&nftables.Rule{
+		Table: r.workTable,
+		Chain: chain,
+		Exprs: expressions,
+	})
+	return nil
+}
+
+func (r *family) addJumpRule(chain *nftables.Chain, to string, ifaceKey expr.MetaKey) {
+	expressions := []expr.Any{
+		&expr.Meta{Key: ifaceKey, Register: 1},
+		&expr.Cmp{
+			Op:       expr.CmpOpEq,
+			Register: 1,
+			Data:     ifname(r.wgIface.Name()),
+		},
+		&expr.Verdict{
+			Kind:  expr.VerdictJump,
+			Chain: to,
+		},
+	}
+
+	_ = r.conn.AddRule(&nftables.Rule{
+		Table: chain.Table,
+		Chain: chain,
+		Exprs: expressions,
+	})
+}
+
+func (r *family) flushWithBackoff() (err error) {
+	backoff := 4
+	backoffTime := 1000 * time.Millisecond
+	for i := 0; ; i++ {
+		err = r.conn.Flush()
+		if err != nil {
+			log.Debugf("failed to flush nftables: %v", err)
+			if !strings.Contains(err.Error(), "busy") {
+				return
+			}
+			log.Error("failed to flush nftables, retrying...")
+			if i == backoff-1 {
+				return err
+			}
+			time.Sleep(backoffTime)
+			backoffTime *= 2
+			continue
+		}
+		break
+	}
+	return
+}
+
+func (r *family) refreshRuleHandles(chain *nftables.Chain, mangle bool) error {
+	if r.workTable == nil || chain == nil {
+		return nil
+	}
+
+	list, err := r.conn.GetRules(r.workTable, chain)
+	if err != nil {
+		return err
+	}
+
+	for _, rule := range list {
+		if len(rule.UserData) == 0 {
+			continue
+		}
+		pr, ok := r.filters[firewall.RuleID(rule.UserData)]
+		if !ok {
+			continue
+		}
+		if mangle {
+			if pr.mangleRule != nil {
+				*pr.mangleRule = *rule
+			}
+		} else {
+			*pr.nftRule = *rule
+		}
+	}
+
+	return nil
+}

client/firewall/nftables/dnat_linux.go

@@ -0,0 +1,550 @@
+//go:build !android
+
+package nftables
+
+import (
+	"fmt"
+	"net/netip"
+
+	"github.com/google/nftables"
+	"github.com/google/nftables/binaryutil"
+	"github.com/google/nftables/expr"
+	"github.com/google/nftables/xt"
+	"github.com/hashicorp/go-multierror"
+	log "github.com/sirupsen/logrus"
+
+	nberrors "github.com/netbirdio/netbird/client/errors"
+	firewall "github.com/netbirdio/netbird/client/firewall/manager"
+)
+
+func (r *family) AddDNATRule(rule firewall.ForwardRule) (firewall.Rule, error) {
+	ruleID := rule.ID()
+	if _, exists := r.rules[ruleID+dnatSuffix]; exists {
+		return rule, nil
+	}
+
+	protoNum, err := r.af.protoNum(rule.Protocol)
+	if err != nil {
+		return nil, fmt.Errorf("convert protocol to number: %w", err)
+	}
+
+	// Request forwarding once the rule is about to be installed, releasing
+	// it if a later step fails so the refcount tracks the real rules.
+	if err := r.ipFwdState.RequestForwarding(); err != nil {
+		return nil, err
+	}
+
+	if err := r.addDnatRedirect(rule, protoNum, ruleID); err != nil {
+		r.releaseForwarding()
+		return nil, err
+	}
+
+	r.addDnatMasq(rule, protoNum, ruleID)
+
+	// Unlike iptables, there's no point in adding "out" rules in the forward chain here as our policy is ACCEPT.
+	// To overcome DROP policies in other chains, we'd have to add rules to the chains there.
+	// We also cannot just add "oif <iface> accept" there and filter in our own table as we don't know what is supposed to be allowed.
+	// TODO: find chains with drop policies and add rules there
+
+	if err := r.conn.Flush(); err != nil {
+		r.releaseForwarding()
+		return nil, fmt.Errorf("flush rules: %w", err)
+	}
+
+	return &rule, nil
+}
+
+func (r *family) addDnatRedirect(rule firewall.ForwardRule, protoNum uint8, ruleID firewall.RuleID) error {
+	dnatExprs := []expr.Any{
+		&expr.Meta{Key: expr.MetaKeyIIFNAME, Register: 1},
+		&expr.Cmp{
+			Op:       expr.CmpOpNeq,
+			Register: 1,
+			Data:     ifname(r.wgIface.Name()),
+		},
+		&expr.Meta{Key: expr.MetaKeyL4PROTO, Register: 1},
+		&expr.Cmp{
+			Op:       expr.CmpOpEq,
+			Register: 1,
+			Data:     []byte{protoNum},
+		},
+		&expr.Payload{
+			DestRegister: 1,
+			Base:         expr.PayloadBaseTransportHeader,
+			Offset:       2,
+			Len:          2,
+		},
+	}
+	dnatExprs = append(dnatExprs, applyPort(&rule.DestinationPort, false)...)
+
+	// shifted translated port is not supported in nftables, so we hand this over to xtables
+	if rule.TranslatedPort.IsRange && len(rule.TranslatedPort.Values) == 2 {
+		if rule.TranslatedPort.Values[0] != rule.DestinationPort.Values[0] ||
+			rule.TranslatedPort.Values[1] != rule.DestinationPort.Values[1] {
+			return r.addXTablesRedirect(dnatExprs, ruleID, rule)
+		}
+	}
+
+	additionalExprs, regProtoMin, regProtoMax, err := r.handleTranslatedPort(rule)
+	if err != nil {
+		return err
+	}
+	dnatExprs = append(dnatExprs, additionalExprs...)
+
+	dnatExprs = append(dnatExprs,
+		&expr.NAT{
+			Type:        expr.NATTypeDestNAT,
+			Family:      uint32(r.af.tableFamily),
+			RegAddrMin:  1,
+			RegProtoMin: regProtoMin,
+			RegProtoMax: regProtoMax,
+		},
+	)
+
+	dnatRule := &nftables.Rule{
+		Table:    r.workTable,
+		Chain:    r.chains[chainNameRoutingRdr],
+		Exprs:    dnatExprs,
+		UserData: []byte(ruleID + dnatSuffix),
+	}
+	r.conn.AddRule(dnatRule)
+	r.rules[ruleID+dnatSuffix] = dnatRule
+
+	return nil
+}
+
+func (r *family) handleTranslatedPort(rule firewall.ForwardRule) ([]expr.Any, uint32, uint32, error) {
+	switch {
+	case rule.TranslatedPort.IsRange && len(rule.TranslatedPort.Values) == 2:
+		return r.handlePortRange(rule)
+	case len(rule.TranslatedPort.Values) == 0:
+		return r.handleAddressOnly(rule)
+	case len(rule.TranslatedPort.Values) == 1:
+		return r.handleSinglePort(rule)
+	default:
+		return nil, 0, 0, fmt.Errorf("invalid translated port: %v", rule.TranslatedPort)
+	}
+}
+
+func (r *family) handlePortRange(rule firewall.ForwardRule) ([]expr.Any, uint32, uint32, error) {
+	exprs := []expr.Any{
+		&expr.Immediate{
+			Register: 1,
+			Data:     rule.TranslatedAddress.AsSlice(),
+		},
+		&expr.Immediate{
+			Register: 2,
+			Data:     binaryutil.BigEndian.PutUint16(rule.TranslatedPort.Values[0]),
+		},
+		&expr.Immediate{
+			Register: 3,
+			Data:     binaryutil.BigEndian.PutUint16(rule.TranslatedPort.Values[1]),
+		},
+	}
+	return exprs, 2, 3, nil
+}
+
+func (r *family) handleAddressOnly(rule firewall.ForwardRule) ([]expr.Any, uint32, uint32, error) {
+	exprs := []expr.Any{
+		&expr.Immediate{
+			Register: 1,
+			Data:     rule.TranslatedAddress.AsSlice(),
+		},
+	}
+	return exprs, 0, 0, nil
+}
+
+func (r *family) handleSinglePort(rule firewall.ForwardRule) ([]expr.Any, uint32, uint32, error) {
+	exprs := []expr.Any{
+		&expr.Immediate{
+			Register: 1,
+			Data:     rule.TranslatedAddress.AsSlice(),
+		},
+		&expr.Immediate{
+			Register: 2,
+			Data:     binaryutil.BigEndian.PutUint16(rule.TranslatedPort.Values[0]),
+		},
+	}
+	return exprs, 2, 0, nil
+}
+
+func (r *family) addXTablesRedirect(dnatExprs []expr.Any, ruleID firewall.RuleID, rule firewall.ForwardRule) error {
+	dnatExprs = append(dnatExprs,
+		&expr.Counter{},
+		&expr.Target{
+			Name: "DNAT",
+			Rev:  2,
+			Info: &xt.NatRange2{
+				NatRange: xt.NatRange{
+					Flags:   uint(xt.NatRangeMapIPs | xt.NatRangeProtoSpecified | xt.NatRangeProtoOffset),
+					MinIP:   rule.TranslatedAddress.AsSlice(),
+					MaxIP:   rule.TranslatedAddress.AsSlice(),
+					MinPort: rule.TranslatedPort.Values[0],
+					MaxPort: rule.TranslatedPort.Values[1],
+				},
+				BasePort: rule.DestinationPort.Values[0],
+			},
+		},
+	)
+
+	natTable := &nftables.Table{
+		Name:   tableNat,
+		Family: r.af.tableFamily,
+	}
+	dnatRule := &nftables.Rule{
+		Table: natTable,
+		Chain: &nftables.Chain{
+			Name:     chainNameNatPrerouting,
+			Table:    natTable,
+			Type:     nftables.ChainTypeNAT,
+			Hooknum:  nftables.ChainHookPrerouting,
+			Priority: nftables.ChainPriorityNATDest,
+		},
+		Exprs:    dnatExprs,
+		UserData: []byte(ruleID + dnatSuffix),
+	}
+	r.conn.AddRule(dnatRule)
+	r.rules[ruleID+dnatSuffix] = dnatRule
+
+	return nil
+}
+
+func (r *family) addDnatMasq(rule firewall.ForwardRule, protoNum uint8, ruleID firewall.RuleID) {
+	masqExprs := []expr.Any{
+		&expr.Meta{Key: expr.MetaKeyOIFNAME, Register: 1},
+		&expr.Cmp{
+			Op:       expr.CmpOpEq,
+			Register: 1,
+			Data:     ifname(r.wgIface.Name()),
+		},
+		&expr.Meta{Key: expr.MetaKeyL4PROTO, Register: 1},
+		&expr.Cmp{
+			Op:       expr.CmpOpEq,
+			Register: 1,
+			Data:     []byte{protoNum},
+		},
+		&expr.Payload{
+			DestRegister: 1,
+			Base:         expr.PayloadBaseNetworkHeader,
+			Offset:       r.af.dstAddrOffset,
+			Len:          r.af.addrLen,
+		},
+		&expr.Cmp{
+			Op:       expr.CmpOpEq,
+			Register: 1,
+			Data:     rule.TranslatedAddress.AsSlice(),
+		},
+	}
+
+	masqExprs = append(masqExprs, applyPort(&rule.TranslatedPort, false)...)
+	masqExprs = append(masqExprs, &expr.Masq{})
+
+	masqRule := &nftables.Rule{
+		Table:    r.workTable,
+		Chain:    r.chains[chainNameRoutingNat],
+		Exprs:    masqExprs,
+		UserData: []byte(ruleID + snatSuffix),
+	}
+	r.conn.AddRule(masqRule)
+	r.rules[ruleID+snatSuffix] = masqRule
+}
+
+func (r *family) DeleteDNATRule(rule firewall.Rule) error {
+	ruleID := rule.ID()
+
+	if err := r.refreshRulesMap(); err != nil {
+		return fmt.Errorf(refreshRulesMapError, err)
+	}
+
+	var merr *multierror.Error
+	var needsFlush bool
+	var found bool
+
+	if dnatRule, exists := r.rules[ruleID+dnatSuffix]; exists {
+		found = true
+		if dnatRule.Handle == 0 {
+			log.Warnf("dnat rule %s has no handle, removing stale entry", ruleID+dnatSuffix)
+			delete(r.rules, ruleID+dnatSuffix)
+		} else if err := r.conn.DelRule(dnatRule); err != nil {
+			merr = multierror.Append(merr, fmt.Errorf("delete dnat rule: %w", err))
+		} else {
+			needsFlush = true
+		}
+	}
+
+	if masqRule, exists := r.rules[ruleID+snatSuffix]; exists {
+		found = true
+		if masqRule.Handle == 0 {
+			log.Warnf("snat rule %s has no handle, removing stale entry", ruleID+snatSuffix)
+			delete(r.rules, ruleID+snatSuffix)
+		} else if err := r.conn.DelRule(masqRule); err != nil {
+			merr = multierror.Append(merr, fmt.Errorf("delete snat rule: %w", err))
+		} else {
+			needsFlush = true
+		}
+	}
+
+	if needsFlush {
+		if err := r.conn.Flush(); err != nil {
+			merr = multierror.Append(merr, fmt.Errorf(flushError, err))
+		}
+	}
+
+	if merr != nil {
+		return nberrors.FormatErrorOrNil(merr)
+	}
+
+	delete(r.rules, ruleID+dnatSuffix)
+	delete(r.rules, ruleID+snatSuffix)
+
+	// Release once, only if the rule was present and removed.
+	if found {
+		r.releaseForwarding()
+	}
+
+	return nil
+}
+
+// releaseForwarding drops one IP forwarding reference, logging any error.
+func (r *family) releaseForwarding() {
+	if err := r.ipFwdState.ReleaseForwarding(); err != nil {
+		log.Errorf("release IP forwarding: %v", err)
+	}
+}
+
+func (r *family) AddInboundDNAT(localAddr netip.Addr, protocol firewall.Protocol, originalPort, translatedPort uint16) error {
+	ruleID := firewall.RuleID(fmt.Sprintf("inbound-dnat-%s-%s-%d-%d", localAddr.String(), protocol, originalPort, translatedPort))
+
+	if _, exists := r.rules[ruleID]; exists {
+		return nil
+	}
+
+	protoNum, err := r.af.protoNum(protocol)
+	if err != nil {
+		return fmt.Errorf("convert protocol to number: %w", err)
+	}
+
+	exprs := []expr.Any{
+		&expr.Meta{Key: expr.MetaKeyIIFNAME, Register: 1},
+		&expr.Cmp{
+			Op:       expr.CmpOpEq,
+			Register: 1,
+			Data:     ifname(r.wgIface.Name()),
+		},
+		&expr.Meta{Key: expr.MetaKeyL4PROTO, Register: 2},
+		&expr.Cmp{
+			Op:       expr.CmpOpEq,
+			Register: 2,
+			Data:     []byte{protoNum},
+		},
+		&expr.Payload{
+			DestRegister: 3,
+			Base:         expr.PayloadBaseTransportHeader,
+			Offset:       2,
+			Len:          2,
+		},
+		&expr.Cmp{
+			Op:       expr.CmpOpEq,
+			Register: 3,
+			Data:     binaryutil.BigEndian.PutUint16(originalPort),
+		},
+	}
+
+	bits := 32
+	if localAddr.Is6() {
+		bits = 128
+	}
+	exprs = append(exprs, prefixMatchExprs(r.af, netip.PrefixFrom(localAddr, bits), false)...)
+
+	exprs = append(exprs,
+		&expr.Immediate{
+			Register: 1,
+			Data:     localAddr.AsSlice(),
+		},
+		&expr.Immediate{
+			Register: 2,
+			Data:     binaryutil.BigEndian.PutUint16(translatedPort),
+		},
+		&expr.NAT{
+			Type:        expr.NATTypeDestNAT,
+			Family:      uint32(r.af.tableFamily),
+			RegAddrMin:  1,
+			RegProtoMin: 2,
+			RegProtoMax: 0,
+		},
+	)
+
+	dnatRule := &nftables.Rule{
+		Table:    r.workTable,
+		Chain:    r.chains[chainNameRoutingRdr],
+		Exprs:    exprs,
+		UserData: []byte(ruleID),
+	}
+	r.conn.AddRule(dnatRule)
+
+	if err := r.conn.Flush(); err != nil {
+		return fmt.Errorf("add inbound DNAT rule: %w", err)
+	}
+
+	r.rules[ruleID] = dnatRule
+
+	return nil
+}
+
+// RemoveInboundDNAT removes an inbound DNAT rule.
+func (r *family) RemoveInboundDNAT(localAddr netip.Addr, protocol firewall.Protocol, originalPort, translatedPort uint16) error {
+	if err := r.refreshRulesMap(); err != nil {
+		return fmt.Errorf(refreshRulesMapError, err)
+	}
+
+	ruleID := firewall.RuleID(fmt.Sprintf("inbound-dnat-%s-%s-%d-%d", localAddr.String(), protocol, originalPort, translatedPort))
+
+	rule, exists := r.rules[ruleID]
+	if !exists {
+		return nil
+	}
+
+	if rule.Handle == 0 {
+		log.Warnf("inbound DNAT rule %s has no handle, removing stale entry", ruleID)
+		delete(r.rules, ruleID)
+		return nil
+	}
+
+	if err := r.conn.DelRule(rule); err != nil {
+		return fmt.Errorf("delete inbound DNAT rule %s: %w", ruleID, err)
+	}
+	if err := r.conn.Flush(); err != nil {
+		return fmt.Errorf("flush delete inbound DNAT rule: %w", err)
+	}
+	delete(r.rules, ruleID)
+
+	return nil
+}
+
+// ensureNATOutputChain lazily creates the OUTPUT NAT chain on first use.
+func (r *family) ensureNATOutputChain() error {
+	if _, exists := r.chains[chainNameNATOutput]; exists {
+		return nil
+	}
+
+	r.chains[chainNameNATOutput] = r.conn.AddChain(&nftables.Chain{
+		Name:     chainNameNATOutput,
+		Table:    r.workTable,
+		Hooknum:  nftables.ChainHookOutput,
+		Priority: nftables.ChainPriorityNATDest,
+		Type:     nftables.ChainTypeNAT,
+	})
+
+	if err := r.conn.Flush(); err != nil {
+		delete(r.chains, chainNameNATOutput)
+		return fmt.Errorf("create NAT output chain: %w", err)
+	}
+	return nil
+}
+
+// AddOutputDNAT adds an OUTPUT chain DNAT rule for locally-generated traffic.
+func (r *family) AddOutputDNAT(localAddr netip.Addr, protocol firewall.Protocol, originalPort, translatedPort uint16) error {
+	ruleID := firewall.RuleID(fmt.Sprintf("output-dnat-%s-%s-%d-%d", localAddr.String(), protocol, originalPort, translatedPort))
+
+	if _, exists := r.rules[ruleID]; exists {
+		return nil
+	}
+
+	if err := r.ensureNATOutputChain(); err != nil {
+		return err
+	}
+
+	protoNum, err := r.af.protoNum(protocol)
+	if err != nil {
+		return fmt.Errorf("convert protocol to number: %w", err)
+	}
+
+	exprs := []expr.Any{
+		&expr.Meta{Key: expr.MetaKeyL4PROTO, Register: 1},
+		&expr.Cmp{
+			Op:       expr.CmpOpEq,
+			Register: 1,
+			Data:     []byte{protoNum},
+		},
+		&expr.Payload{
+			DestRegister: 2,
+			Base:         expr.PayloadBaseTransportHeader,
+			Offset:       2,
+			Len:          2,
+		},
+		&expr.Cmp{
+			Op:       expr.CmpOpEq,
+			Register: 2,
+			Data:     binaryutil.BigEndian.PutUint16(originalPort),
+		},
+	}
+
+	bits := 32
+	if localAddr.Is6() {
+		bits = 128
+	}
+	exprs = append(exprs, prefixMatchExprs(r.af, netip.PrefixFrom(localAddr, bits), false)...)
+
+	exprs = append(exprs,
+		&expr.Immediate{
+			Register: 1,
+			Data:     localAddr.AsSlice(),
+		},
+		&expr.Immediate{
+			Register: 2,
+			Data:     binaryutil.BigEndian.PutUint16(translatedPort),
+		},
+		&expr.NAT{
+			Type:        expr.NATTypeDestNAT,
+			Family:      uint32(r.af.tableFamily),
+			RegAddrMin:  1,
+			RegProtoMin: 2,
+		},
+	)
+
+	dnatRule := &nftables.Rule{
+		Table:    r.workTable,
+		Chain:    r.chains[chainNameNATOutput],
+		Exprs:    exprs,
+		UserData: []byte(ruleID),
+	}
+	r.conn.AddRule(dnatRule)
+
+	if err := r.conn.Flush(); err != nil {
+		return fmt.Errorf("add output DNAT rule: %w", err)
+	}
+
+	r.rules[ruleID] = dnatRule
+
+	return nil
+}
+
+// RemoveOutputDNAT removes an OUTPUT chain DNAT rule.
+func (r *family) RemoveOutputDNAT(localAddr netip.Addr, protocol firewall.Protocol, originalPort, translatedPort uint16) error {
+	if err := r.refreshRulesMap(); err != nil {
+		return fmt.Errorf(refreshRulesMapError, err)
+	}
+
+	ruleID := firewall.RuleID(fmt.Sprintf("output-dnat-%s-%s-%d-%d", localAddr.String(), protocol, originalPort, translatedPort))
+
+	rule, exists := r.rules[ruleID]
+	if !exists {
+		return nil
+	}
+
+	if rule.Handle == 0 {
+		log.Warnf("output DNAT rule %s has no handle, removing stale entry", ruleID)
+		delete(r.rules, ruleID)
+		return nil
+	}
+
+	if err := r.conn.DelRule(rule); err != nil {
+		return fmt.Errorf("delete output DNAT rule %s: %w", ruleID, err)
+	}
+	if err := r.conn.Flush(); err != nil {
+		return fmt.Errorf("flush delete output DNAT rule: %w", err)
+	}
+	delete(r.rules, ruleID)
+
+	return nil
+}

client/firewall/nftables/external_chain_monitor_linux.go

@@ -52,9 +52,10 @@ func (m *externalChainMonitor) start() {
 
 	ctx, cancel := context.WithCancel(context.Background())
 	m.cancel = cancel
-	m.done = make(chan struct{})
+	done := make(chan struct{})
+	m.done = done
 
-	go m.run(ctx)
+	go m.run(ctx, done)
 }
 
 func (m *externalChainMonitor) stop() {
@@ -72,8 +73,8 @@ func (m *externalChainMonitor) stop() {
 	<-done
 }
 
-func (m *externalChainMonitor) run(ctx context.Context) {
-	defer close(m.done)
+func (m *externalChainMonitor) run(ctx context.Context, done chan struct{}) {
+	defer close(done)
 
 	bo := &backoff.ExponentialBackOff{
 		InitialInterval:     externalMonitorInitInterval,

client/firewall/nftables/family_linux.go

@@ -0,0 +1,249 @@
+//go:build !android
+
+package nftables
+
+import (
+	"fmt"
+	"net/netip"
+
+	"github.com/coreos/go-iptables/iptables"
+	"github.com/google/nftables"
+	"github.com/hashicorp/go-multierror"
+	log "github.com/sirupsen/logrus"
+
+	nberrors "github.com/netbirdio/netbird/client/errors"
+	"github.com/netbirdio/netbird/client/firewall/firewalld"
+	firewall "github.com/netbirdio/netbird/client/firewall/manager"
+	"github.com/netbirdio/netbird/client/internal/routemanager/ipfwdstate"
+	"github.com/netbirdio/netbird/client/internal/routemanager/refcounter"
+)
+
+const (
+	tableNat      = "nat"
+	tableMangle   = "mangle"
+	tableRaw      = "raw"
+	tableSecurity = "security"
+
+	chainNameNatPrerouting = "PREROUTING"
+	chainNameRoutingFw     = "netbird-rt-fwd"
+	chainNameRoutingNat    = "netbird-rt-postrouting"
+	chainNameRoutingRdr    = "netbird-rt-redirect"
+	chainNameNATOutput     = "netbird-nat-output"
+	chainNameForward       = "FORWARD"
+	chainNameMangleForward = "netbird-mangle-forward"
+
+	// Peer ACL chain names.
+	chainNameInputRules        = "netbird-acl-input-rules"
+	chainNameInputFilter       = "netbird-acl-input-filter"
+	chainNameForwardFilter     = "netbird-acl-forward-filter"
+	chainNameManglePrerouting  = "netbird-mangle-prerouting"
+	chainNameManglePostrouting = "netbird-mangle-postrouting"
+
+	flushError = "flush: %w"
+
+	firewalldTableName = "firewalld"
+
+	userDataAcceptForwardRuleIif = "frwacceptiif"
+	userDataAcceptForwardRuleOif = "frwacceptoif"
+	userDataAcceptInputRule      = "inputaccept"
+
+	dnatSuffix firewall.RuleID = "_dnat"
+	snatSuffix firewall.RuleID = "_snat"
+
+	// ipv4TCPHeaderSize is the minimum IPv4 (20) + TCP (20) header size for MSS calculation.
+	ipv4TCPHeaderSize = 40
+	// ipv6TCPHeaderSize is the minimum IPv6 (40) + TCP (20) header size for MSS calculation.
+	ipv6TCPHeaderSize = 60
+
+	// maxPrefixesSet 1638 prefixes start to fail, taking some margin
+	maxPrefixesSet       = 1500
+	refreshRulesMapError = "refresh rules map: %w"
+)
+
+var (
+	errFilterTableNotFound = fmt.Errorf("'filter' table not found")
+)
+
+type setInput struct {
+	set      firewall.Set
+	prefixes []netip.Prefix
+}
+
+// family holds the per-address-family nftables state. One instance
+// handles route ACLs, peer ACLs, NAT, DNAT, and MSS clamping for a
+// single family; the top-level Manager owns one for v4 and another
+// for v6. The name predates the peer-ACL absorption; it's effectively
+// the per-family backend now.
+type family struct {
+	conn        *nftables.Conn
+	workTable   *nftables.Table
+	filterTable *nftables.Table
+	chains      map[string]*nftables.Chain
+
+	// filters holds peer + route filter rules keyed by content hash.
+	// AddFilterRule writes here; DeleteFilterRule looks up by id.
+	filters map[firewall.RuleID]*Rule
+
+	// rules holds NAT, DNAT, and external accept rules (auxiliary
+	// plumbing that isn't a filter rule).
+	rules map[firewall.RuleID]*nftables.Rule
+
+	// Peer ACL chain handles.
+	chainInputRules    *nftables.Chain
+	chainPrerouting    *nftables.Chain
+	routingFwChainName string
+
+	ipsetCounter *refcounter.Counter[string, setInput, *nftables.Set]
+
+	af               addrFamily
+	wgIface          iFaceMapper
+	ipFwdState       *ipfwdstate.IPForwardingState
+	legacyManagement bool
+	mtu              uint16
+}
+
+func newFamily(workTable *nftables.Table, wgIface iFaceMapper, mtu uint16) (*family, error) {
+	r := &family{
+		conn:               &nftables.Conn{},
+		workTable:          workTable,
+		chains:             make(map[string]*nftables.Chain),
+		filters:            make(map[firewall.RuleID]*Rule),
+		rules:              make(map[firewall.RuleID]*nftables.Rule),
+		routingFwChainName: chainNameRoutingFw,
+		af:                 familyForAddr(workTable.Family == nftables.TableFamilyIPv4),
+		wgIface:            wgIface,
+		ipFwdState:         ipfwdstate.NewIPForwardingState(),
+		mtu:                mtu,
+	}
+
+	r.ipsetCounter = refcounter.New(
+		r.createIpSet,
+		r.deleteIpSet,
+	)
+
+	var err error
+	r.filterTable, err = r.loadFilterTable()
+	if err != nil {
+		log.Debugf("ip filter table not found: %v", err)
+	}
+
+	return r, nil
+}
+
+func (r *family) init(workTable *nftables.Table) error {
+	r.workTable = workTable
+
+	if err := r.removeAcceptFilterRules(); err != nil {
+		log.Errorf("failed to clean up rules from filter table: %s", err)
+	}
+
+	if err := r.createContainers(); err != nil {
+		return fmt.Errorf("create containers: %w", err)
+	}
+
+	if err := r.setupDataPlaneMark(); err != nil {
+		log.Errorf("failed to set up data plane mark: %v", err)
+	}
+
+	if err := r.createDefaultChains(); err != nil {
+		return fmt.Errorf("create default acl chains: %w", err)
+	}
+
+	return nil
+}
+
+// Reset cleans existing nftables filter table rules from the system
+func (r *family) Reset() error {
+	// clear without deleting the ipsets, the nf table will be deleted by the caller
+	r.ipsetCounter.Clear()
+
+	var merr *multierror.Error
+
+	if err := r.removeAcceptFilterRules(); err != nil {
+		merr = multierror.Append(merr, fmt.Errorf("remove accept filter rules: %w", err))
+	}
+
+	if err := firewalld.UntrustInterface(r.wgIface.Name()); err != nil {
+		merr = multierror.Append(merr, err)
+	}
+
+	if err := r.removeNatPreroutingRules(); err != nil {
+		merr = multierror.Append(merr, fmt.Errorf("remove filter prerouting rules: %w", err))
+	}
+
+	return nberrors.FormatErrorOrNil(merr)
+}
+
+func (r *family) loadFilterTable() (*nftables.Table, error) {
+	tables, err := r.conn.ListTablesOfFamily(r.af.tableFamily)
+	if err != nil {
+		return nil, fmt.Errorf("list tables: %w", err)
+	}
+
+	for _, table := range tables {
+		if table.Name == "filter" {
+			return table, nil
+		}
+	}
+
+	return nil, errFilterTableNotFound
+}
+
+func hookName(hook *nftables.ChainHook) string {
+	if hook == nil {
+		return "unknown"
+	}
+	switch *hook {
+	case *nftables.ChainHookForward:
+		return chainNameForward
+	case *nftables.ChainHookInput:
+		return chainNameInput
+	default:
+		return fmt.Sprintf("hook(%d)", *hook)
+	}
+}
+
+func familyName(family nftables.TableFamily) string {
+	switch family {
+	case nftables.TableFamilyIPv4:
+		return "ip"
+	case nftables.TableFamilyIPv6:
+		return "ip6"
+	case nftables.TableFamilyINet:
+		return "inet"
+	default:
+		return fmt.Sprintf("family(%d)", family)
+	}
+}
+
+func (r *family) iptablesProto() iptables.Protocol {
+	if r.af.tableFamily == nftables.TableFamilyIPv6 {
+		return iptables.ProtocolIPv6
+	}
+	return iptables.ProtocolIPv4
+}
+
+func (r *family) refreshRulesMap() error {
+	var merr *multierror.Error
+	newRules := make(map[firewall.RuleID]*nftables.Rule)
+	for _, chain := range r.chains {
+		rules, err := r.conn.GetRules(chain.Table, chain)
+		if err != nil {
+			merr = multierror.Append(merr, fmt.Errorf("list rules for chain %s: %w", chain.Name, err))
+			// preserve existing entries for this chain since we can't verify their state
+			for k, v := range r.rules {
+				if v.Chain != nil && v.Chain.Name == chain.Name {
+					newRules[k] = v
+				}
+			}
+			continue
+		}
+		for _, rule := range rules {
+			if len(rule.UserData) > 0 {
+				newRules[firewall.RuleID(rule.UserData)] = rule
+			}
+		}
+	}
+	r.rules = newRules
+	return nberrors.FormatErrorOrNil(merr)
+}

client/firewall/nftables/filter_linux.go

@@ -0,0 +1,441 @@
+//go:build !android
+
+package nftables
+
+import (
+	"fmt"
+	"net"
+	"net/netip"
+	"slices"
+
+	"github.com/google/nftables"
+	"github.com/google/nftables/binaryutil"
+	"github.com/google/nftables/expr"
+	"github.com/hashicorp/go-multierror"
+	log "github.com/sirupsen/logrus"
+
+	nberrors "github.com/netbirdio/netbird/client/errors"
+	firewall "github.com/netbirdio/netbird/client/firewall/manager"
+	nbid "github.com/netbirdio/netbird/client/internal/acl/id"
+)
+
+// AddFilterRule installs one nftables packet-filter rule. With
+// destination empty the rule goes to the peer ACL input chain plus a
+// paired prerouting mangle rule for the redirect mark. With
+// destination set (prefix or named set) it goes to the route ACL
+// forward chain. Multi-source rules collapse to one nftables rule
+// backed by the shared refcounted hash:net set.
+func (r *family) AddFilterRule(
+	id []byte,
+	sources []netip.Prefix,
+	destination firewall.Network,
+	proto firewall.Protocol,
+	sPort *firewall.Port,
+	dPort *firewall.Port,
+	action firewall.Action,
+) (firewall.Rule, error) {
+	isRoute := !destination.IsZero()
+
+	ruleID := nbid.GenerateRuleID(sources, destination, proto, sPort, dPort, action)
+	if existing, ok := r.filters[ruleID]; ok {
+		return existing, nil
+	}
+
+	srcExprs, err := r.applyNetwork(sourceNetwork(sources), sources, true)
+	if err != nil {
+		return nil, fmt.Errorf("apply source: %w", err)
+	}
+
+	var exprs []expr.Any
+	if isRoute {
+		exprs, err = r.buildRouteFilterExprs(srcExprs, destination, proto, sPort, dPort)
+	} else {
+		exprs, err = r.buildPeerFilterExprs(srcExprs, proto, sPort, dPort)
+	}
+	if err != nil {
+		r.dropNetworkMatch(srcExprs)
+		return nil, err
+	}
+
+	mainExprs := slices.Clone(exprs)
+	verdict := expr.VerdictAccept
+	if action == firewall.ActionDrop {
+		verdict = expr.VerdictDrop
+	}
+	mainExprs = append(mainExprs, &expr.Verdict{Kind: verdict})
+
+	chain := r.chainInputRules
+	if isRoute {
+		chain = r.chains[chainNameRoutingFw]
+	}
+
+	userData := []byte(ruleID)
+	nftRule := &nftables.Rule{
+		Table:    r.workTable,
+		Chain:    chain,
+		Exprs:    mainExprs,
+		UserData: userData,
+	}
+	if action == firewall.ActionDrop {
+		nftRule = r.conn.InsertRule(nftRule)
+	} else {
+		nftRule = r.conn.AddRule(nftRule)
+	}
+	if err := r.conn.Flush(); err != nil {
+		r.dropNetworkMatch(exprs)
+		return nil, fmt.Errorf(flushError, err)
+	}
+
+	rule := &Rule{
+		nftRule: nftRule,
+		sources: sources,
+		id:      ruleID,
+	}
+	if !isRoute {
+		rule.mangleRule = r.createPreroutingRule(exprs, userData)
+	}
+	r.filters[ruleID] = rule
+
+	log.Debugf("added filter rule: sources=%v, destination=%v, proto=%v, sPort=%v, dPort=%v, action=%v",
+		sources, destination, proto, sPort, dPort, action)
+	return rule, nil
+}
+
+// buildPeerFilterExprs assembles the input-chain (peer ACL) match: the
+// IP-header protocol byte read via Payload, then source, then ports
+// (no counter), matching the historical peer shape so per-rule kernel
+// state is identical to pre-unification.
+func (r *family) buildPeerFilterExprs(
+	srcExprs []expr.Any,
+	proto firewall.Protocol,
+	sPort, dPort *firewall.Port,
+) ([]expr.Any, error) {
+	var exprs []expr.Any
+
+	if proto != firewall.ProtocolALL {
+		protoNum, err := r.af.protoNum(proto)
+		if err != nil {
+			return nil, fmt.Errorf("convert protocol to number: %w", err)
+		}
+		exprs = append(exprs,
+			&expr.Payload{
+				DestRegister: 1,
+				Base:         expr.PayloadBaseNetworkHeader,
+				Offset:       r.af.protoOffset,
+				Len:          1,
+			},
+			&expr.Cmp{Op: expr.CmpOpEq, Register: 1, Data: []byte{protoNum}},
+		)
+	}
+	exprs = append(exprs, srcExprs...)
+	exprs = append(exprs, applyPort(sPort, true)...)
+	exprs = append(exprs, applyPort(dPort, false)...)
+	return exprs, nil
+}
+
+// buildRouteFilterExprs assembles the forward-chain (route ACL) match:
+// source, then destination, then optional proto/ports, then a counter.
+func (r *family) buildRouteFilterExprs(
+	srcExprs []expr.Any,
+	destination firewall.Network,
+	proto firewall.Protocol,
+	sPort, dPort *firewall.Port,
+) ([]expr.Any, error) {
+	exprs := append([]expr.Any{}, srcExprs...)
+
+	destExprs, err := r.applyNetwork(destination, nil, false)
+	if err != nil {
+		return nil, fmt.Errorf("apply destination: %w", err)
+	}
+	exprs = append(exprs, destExprs...)
+
+	if proto != firewall.ProtocolALL {
+		protoNum, err := r.af.protoNum(proto)
+		if err != nil {
+			r.dropNetworkMatch(destExprs)
+			return nil, fmt.Errorf("convert protocol to number: %w", err)
+		}
+		exprs = append(exprs,
+			&expr.Meta{Key: expr.MetaKeyL4PROTO, Register: 1},
+			&expr.Cmp{Op: expr.CmpOpEq, Register: 1, Data: []byte{protoNum}},
+		)
+		exprs = append(exprs, applyPort(sPort, true)...)
+		exprs = append(exprs, applyPort(dPort, false)...)
+	}
+
+	exprs = append(exprs, &expr.Counter{})
+	return exprs, nil
+}
+
+func (r *family) hasRule(id firewall.RuleID) bool {
+	_, ok := r.filters[id]
+	return ok
+}
+
+func (r *family) hasDNATRule(id firewall.RuleID) bool {
+	_, ok := r.rules[id+dnatSuffix]
+	return ok
+}
+
+// DeleteFilterRule removes a previously installed filter rule. Source
+// set references are recovered from the stored rule's expressions via
+// findSets and dropped from the shared refcounter.
+func (r *family) DeleteFilterRule(rule firewall.Rule) error {
+	ruleID := rule.ID()
+	pr, ok := r.filters[ruleID]
+	if !ok {
+		log.Debugf("filter rule %s not found", ruleID)
+		return nil
+	}
+
+	// A freshly added rule carries no handle until it is read back from
+	// the kernel, and Flush only refreshes the peer chains. Pull live
+	// handles for this rule's chain before deciding it is stale so route
+	// rules (which Flush never refreshes) can actually be deleted.
+	if pr.nftRule.Handle == 0 {
+		if err := r.refreshRuleHandles(pr.nftRule.Chain, false); err != nil {
+			log.Warnf("refresh handles for chain %s: %v", pr.nftRule.Chain.Name, err)
+		}
+		if pr.mangleRule != nil {
+			if err := r.refreshRuleHandles(r.chainPrerouting, true); err != nil {
+				log.Warnf("refresh mangle handles: %v", err)
+			}
+		}
+	}
+
+	if pr.nftRule.Handle == 0 {
+		log.Warnf("filter rule %s has no handle, removing stale entry", ruleID)
+		r.dropNetworkMatch(pr.nftRule.Exprs)
+		delete(r.filters, ruleID)
+		return nil
+	}
+
+	if err := r.conn.DelRule(pr.nftRule); err != nil {
+		log.Errorf("queue rule delete: %v", err)
+	}
+	if pr.mangleRule != nil {
+		if err := r.conn.DelRule(pr.mangleRule); err != nil {
+			log.Errorf("queue mangle rule delete: %v", err)
+		}
+	}
+	if err := r.conn.Flush(); err != nil {
+		return fmt.Errorf("flush delete %s: %w", ruleID, err)
+	}
+
+	r.dropNetworkMatch(pr.nftRule.Exprs)
+	delete(r.filters, ruleID)
+	return nil
+}
+
+func (r *family) decrementSetCounter(rule *nftables.Rule) error {
+	if r.ipsetCounter == nil {
+		return nil
+	}
+	sets := findSets(rule)
+
+	var merr *multierror.Error
+	for _, setName := range sets {
+		if _, err := r.ipsetCounter.Decrement(setName); err != nil {
+			merr = multierror.Append(merr, fmt.Errorf("decrement set counter: %w", err))
+		}
+	}
+
+	return nberrors.FormatErrorOrNil(merr)
+}
+
+// dropNetworkMatch undoes whatever the source/destination match
+// reserved. Safe to call when the spec is empty or holds only inline
+// matchers.
+func (r *family) dropNetworkMatch(exprs []expr.Any) {
+	if r.ipsetCounter == nil {
+		return
+	}
+	for _, e := range exprs {
+		lookup, ok := e.(*expr.Lookup)
+		if !ok {
+			continue
+		}
+		if _, err := r.ipsetCounter.Decrement(lookup.SetName); err != nil {
+			log.Errorf("rollback ipset decrement %s: %v", lookup.SetName, err)
+		}
+	}
+}
+
+func (r *family) applyNetwork(
+	network firewall.Network,
+	setPrefixes []netip.Prefix,
+	isSource bool,
+) ([]expr.Any, error) {
+	if network.IsSet() {
+		exprs, err := r.getIpSet(network.Set, setPrefixes, isSource)
+		if err != nil {
+			side := "destination"
+			if isSource {
+				side = "source"
+			}
+			return nil, fmt.Errorf("%s set: %w", side, err)
+		}
+		return exprs, nil
+	}
+
+	if network.IsPrefix() {
+		return prefixMatchExprs(r.af, network.Prefix, isSource), nil
+	}
+
+	return nil, nil
+}
+
+// prefixMatchExprs is the family-aware match sequence for a CIDR
+// prefix. /0 returns nil; a host prefix (full bit length for the
+// family) skips the bitwise step since the mask is all-ones. Shared
+// between family and aclManager so both treat single prefixes
+// identically.
+func prefixMatchExprs(af addrFamily, prefix netip.Prefix, isSource bool) []expr.Any {
+	offset := af.dstAddrOffset
+	if isSource {
+		offset = af.srcAddrOffset
+	}
+
+	ones := prefix.Bits()
+	if ones == 0 {
+		return nil
+	}
+
+	payload := &expr.Payload{
+		DestRegister: 1,
+		Base:         expr.PayloadBaseNetworkHeader,
+		Offset:       offset,
+		Len:          af.addrLen,
+	}
+	cmp := &expr.Cmp{
+		Op:       expr.CmpOpEq,
+		Register: 1,
+		Data:     prefix.Masked().Addr().AsSlice(),
+	}
+
+	if ones == af.totalBits {
+		return []expr.Any{payload, cmp}
+	}
+
+	mask := net.CIDRMask(ones, af.totalBits)
+	xor := make([]byte, af.addrLen)
+	return []expr.Any{
+		payload,
+		&expr.Bitwise{
+			DestRegister:   1,
+			SourceRegister: 1,
+			Len:            af.addrLen,
+			Mask:           mask,
+			Xor:            xor,
+		},
+		cmp,
+	}
+}
+
+func applyPort(port *firewall.Port, isSource bool) []expr.Any {
+	if port == nil {
+		return nil
+	}
+
+	var exprs []expr.Any
+
+	// src
+	offset := uint32(2)
+	if isSource {
+		// dst
+		offset = 0
+	}
+
+	exprs = append(exprs, &expr.Payload{
+		DestRegister: 1,
+		Base:         expr.PayloadBaseTransportHeader,
+		Offset:       offset,
+		Len:          2,
+	})
+
+	if port.IsRange && len(port.Values) == 2 {
+		exprs = append(exprs,
+			&expr.Range{
+				Op:       expr.CmpOpEq,
+				Register: 1,
+				FromData: binaryutil.BigEndian.PutUint16(port.Values[0]),
+				ToData:   binaryutil.BigEndian.PutUint16(port.Values[1]),
+			},
+		)
+	} else {
+		for i, p := range port.Values {
+			if i > 0 {
+				exprs = append(exprs, &expr.Bitwise{
+					SourceRegister: 1,
+					DestRegister:   1,
+					Len:            4,
+					Mask:           []byte{0x00, 0x00, 0xff, 0xff},
+					Xor:            []byte{0x00, 0x00, 0x00, 0x00},
+				})
+			}
+			exprs = append(exprs, &expr.Cmp{
+				Op:       expr.CmpOpEq,
+				Register: 1,
+				Data:     binaryutil.BigEndian.PutUint16(p),
+			})
+		}
+	}
+
+	return exprs
+}
+
+func getCtNewExprs() []expr.Any {
+	return []expr.Any{
+		&expr.Ct{
+			Key:      expr.CtKeySTATE,
+			Register: 1,
+		},
+		&expr.Bitwise{
+			SourceRegister: 1,
+			DestRegister:   1,
+			Len:            4,
+			Mask:           binaryutil.NativeEndian.PutUint32(expr.CtStateBitNEW),
+			Xor:            binaryutil.NativeEndian.PutUint32(0),
+		},
+		&expr.Cmp{
+			Op:       expr.CmpOpNeq,
+			Register: 1,
+			Data:     []byte{0, 0, 0, 0},
+		},
+	}
+}
+
+// sourceNetwork classifies a source-prefix list into the firewall.Network
+// shape the rest of the spec-builder consumes: empty for match-any, a
+// single prefix inline, or an ipset for multiple sources.
+func sourceNetwork(sources []netip.Prefix) firewall.Network {
+	switch {
+	case len(sources) == 0:
+		return firewall.Network{}
+	case len(sources) == 1 && sources[0].Bits() == 0:
+		return firewall.Network{}
+	case len(sources) == 1:
+		return firewall.Network{Prefix: sources[0]}
+	default:
+		return firewall.Network{Set: firewall.NewPrefixSet(sources)}
+	}
+}
+
+func ifname(n string) []byte {
+	b := make([]byte, 16)
+	copy(b, n+"\x00")
+	return b
+}
+
+// findSets scans an nftables rule's expressions for expr.Lookup and
+// returns the named sets in occurrence order. Used at delete time to
+// drop ipsetCounter references; peer and route ACLs go through it.
+func findSets(rule *nftables.Rule) []string {
+	var sets []string
+	for _, e := range rule.Exprs {
+		if lookup, ok := e.(*expr.Lookup); ok {
+			sets = append(sets, lookup.SetName)
+		}
+	}
+	return sets
+}

client/firewall/nftables/ipset_linux.go

@@ -0,0 +1,210 @@
+//go:build !android
+
+package nftables
+
+import (
+	"encoding/binary"
+	"fmt"
+	"net/netip"
+
+	"github.com/google/nftables"
+	"github.com/google/nftables/expr"
+	log "github.com/sirupsen/logrus"
+
+	firewall "github.com/netbirdio/netbird/client/firewall/manager"
+	"github.com/netbirdio/netbird/client/internal/routemanager/refcounter"
+)
+
+func (r *family) getIpSet(set firewall.Set, prefixes []netip.Prefix, isSource bool) ([]expr.Any, error) {
+	ref, err := r.ipsetCounter.Increment(set.HashedName(), setInput{
+		set:      set,
+		prefixes: prefixes,
+	})
+	if err != nil {
+		return nil, fmt.Errorf("create or get ipset: %w", err)
+	}
+
+	return r.getIpSetExprs(ref, isSource)
+}
+
+func (r *family) createIpSet(setName string, input setInput) (*nftables.Set, error) {
+	// overlapping prefixes will result in an error, so we need to merge them
+	prefixes := firewall.MergeIPRanges(input.prefixes)
+
+	nfset := &nftables.Set{
+		Name:    setName,
+		Comment: input.set.Comment(),
+		Table:   r.workTable,
+		// required for prefixes
+		Interval: true,
+		KeyType:  r.af.setKeyType,
+	}
+
+	elements := r.convertPrefixesToSet(prefixes)
+	nElements := len(elements)
+
+	maxElements := maxPrefixesSet * 2
+	initialElements := elements[:min(maxElements, nElements)]
+
+	if err := r.conn.AddSet(nfset, initialElements); err != nil {
+		return nil, fmt.Errorf("error adding set %s: %w", setName, err)
+	}
+	if err := r.conn.Flush(); err != nil {
+		return nil, fmt.Errorf("flush error: %w", err)
+	}
+	log.Debugf("Created new ipset: %s with %d initial prefixes (total prefixes %d)", setName, len(initialElements)/2, len(prefixes))
+
+	// The set is committed now. If a later batch fails, destroy it: the
+	// refcounter records nothing on a create-callback error, so it would
+	// otherwise leak, and a partial source set fails-open for deny rules.
+	if err := r.addRemainingElements(nfset, elements, maxElements); err != nil {
+		if derr := r.deleteIpSet(setName, nfset); derr != nil {
+			log.Warnf("rollback ipset %s after add failure: %v", setName, derr)
+		}
+		return nil, err
+	}
+
+	log.Infof("Created new ipset: %s with %d prefixes", setName, len(prefixes))
+	return nfset, nil
+}
+
+// addRemainingElements adds element batches beyond the initial one in
+// maxElements-sized chunks, flushing each. Called after the set has been
+// created with its first batch.
+func (r *family) addRemainingElements(nfset *nftables.Set, elements []nftables.SetElement, maxElements int) error {
+	nElements := len(elements)
+	for subStart := maxElements; subStart < nElements; subStart += maxElements {
+		subEnd := min(subStart+maxElements, nElements)
+		subElement := elements[subStart:subEnd]
+		nSubPrefixes := len(subElement) / 2
+		log.Tracef("Adding new prefixes (%d) in ipset: %s", nSubPrefixes, nfset.Name)
+		if err := r.conn.SetAddElements(nfset, subElement); err != nil {
+			return fmt.Errorf("error adding prefixes (%d) to set %s: %w", nSubPrefixes, nfset.Name, err)
+		}
+		if err := r.conn.Flush(); err != nil {
+			return fmt.Errorf("flush error: %w", err)
+		}
+		log.Debugf("Added new prefixes (%d) in ipset: %s", nSubPrefixes, nfset.Name)
+	}
+	return nil
+}
+
+func (r *family) convertPrefixesToSet(prefixes []netip.Prefix) []nftables.SetElement {
+	var elements []nftables.SetElement
+	for _, prefix := range prefixes {
+		// nftables needs half-open intervals [firstIP, lastIP) for prefixes
+		// e.g. 10.0.0.0/24 becomes [10.0.0.0, 10.0.1.0), 10.1.1.1/32 becomes [10.1.1.1, 10.1.1.2) etc
+		firstIP := prefix.Addr()
+
+		// For a /0 the last address is the broadcast and its Next() overflows
+		// to an invalid Addr with an empty key, so wrap to the zero address,
+		// which nftables reads as the open end of a full-range interval.
+		var lastKey []byte
+		if prefix.Bits() == 0 {
+			lastKey = make([]byte, r.af.addrLen)
+		} else {
+			lastKey = calculateLastIP(prefix).Next().AsSlice()
+		}
+
+		// the nft tool also adds a zero-address IntervalEnd element, see https://github.com/google/nftables/issues/247
+		// nftables.SetElement{Key: make([]byte, r.af.addrLen), IntervalEnd: true},
+		elements = append(elements,
+			nftables.SetElement{Key: firstIP.AsSlice()},
+			nftables.SetElement{Key: lastKey, IntervalEnd: true},
+		)
+	}
+	return elements
+}
+
+// calculateLastIP determines the last IP in a given prefix.
+func calculateLastIP(prefix netip.Prefix) netip.Addr {
+	masked := prefix.Masked()
+	if masked.Addr().Is4() {
+		hostMask := ^uint32(0) >> masked.Bits()
+		lastIP := uint32FromNetipAddr(masked.Addr()) | hostMask
+		return netip.AddrFrom4(uint32ToBytes(lastIP))
+	}
+
+	// IPv6: set host bits to all 1s
+	b := masked.Addr().As16()
+	bits := masked.Bits()
+	for i := bits; i < 128; i++ {
+		b[i/8] |= 1 << (7 - i%8)
+	}
+	return netip.AddrFrom16(b)
+}
+
+// Utility function to convert netip.Addr to uint32.
+func uint32FromNetipAddr(addr netip.Addr) uint32 {
+	b := addr.As4()
+	return binary.BigEndian.Uint32(b[:])
+}
+
+// Utility function to convert uint32 to a netip-compatible byte slice.
+func uint32ToBytes(ip uint32) [4]byte {
+	var b [4]byte
+	binary.BigEndian.PutUint32(b[:], ip)
+	return b
+}
+
+func (r *family) deleteIpSet(setName string, nfset *nftables.Set) error {
+	r.conn.DelSet(nfset)
+	if err := r.conn.Flush(); err != nil {
+		return fmt.Errorf(flushError, err)
+	}
+
+	log.Debugf("Deleted unused ipset %s", setName)
+	return nil
+}
+
+func (r *family) UpdateSet(set firewall.Set, prefixes []netip.Prefix) error {
+	nfset, err := r.conn.GetSetByName(r.workTable, set.HashedName())
+	if err != nil {
+		return fmt.Errorf("get set %s: %w", set.HashedName(), err)
+	}
+
+	// Overlapping prefixes (e.g. duplicate resolved addresses) make the
+	// interval set reject the batch, so merge them as createIpSet does.
+	prefixes = firewall.MergeIPRanges(prefixes)
+	elements := r.convertPrefixesToSet(prefixes)
+
+	// Add in batches sized like createIpSet so a large update does not
+	// exceed the netlink message size limit.
+	maxElements := maxPrefixesSet * 2
+	for start := 0; start < len(elements); start += maxElements {
+		end := min(start+maxElements, len(elements))
+		if err := r.conn.SetAddElements(nfset, elements[start:end]); err != nil {
+			return fmt.Errorf("add elements to set %s: %w", set.HashedName(), err)
+		}
+		if err := r.conn.Flush(); err != nil {
+			return fmt.Errorf(flushError, err)
+		}
+	}
+
+	log.Debugf("updated set %s with %d prefixes", set.HashedName(), len(prefixes))
+
+	return nil
+}
+
+func (r *family) getIpSetExprs(ref refcounter.Ref[*nftables.Set], isSource bool) ([]expr.Any, error) {
+	// dst offset by default
+	offset := r.af.dstAddrOffset
+	if isSource {
+		// src offset
+		offset = r.af.srcAddrOffset
+	}
+
+	return []expr.Any{
+		&expr.Payload{
+			DestRegister: 1,
+			Base:         expr.PayloadBaseNetworkHeader,
+			Offset:       offset,
+			Len:          r.af.addrLen,
+		},
+		&expr.Lookup{
+			SourceRegister: 1,
+			SetName:        ref.Out.Name,
+			SetID:          ref.Out.ID,
+		},
+	}, nil
+}

client/firewall/nftables/ipset_linux_test.go

@@ -0,0 +1,36 @@
+package nftables
+
+import (
+	"net/netip"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+// TestConvertPrefixesToSetWildcard verifies that a /0 prefix produces a
+// usable interval. The last address of a /0 is the broadcast, whose Next()
+// overflows to an invalid Addr with an empty key; the IntervalEnd must wrap
+// to the zero address instead so nftables sees a full-range interval.
+func TestConvertPrefixesToSetWildcard(t *testing.T) {
+	tests := []struct {
+		name   string
+		af     addrFamily
+		prefix string
+	}{
+		{"IPv4 /0", afIPv4, "0.0.0.0/0"},
+		{"IPv6 /0", afIPv6, "::/0"},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			r := &family{af: tt.af}
+			elements := r.convertPrefixesToSet([]netip.Prefix{netip.MustParsePrefix(tt.prefix)})
+
+			require.Len(t, elements, 2, "expected start and interval-end element")
+			assert.False(t, elements[0].IntervalEnd, "first element is the interval start")
+			assert.True(t, elements[1].IntervalEnd, "second element is the interval end")
+			assert.Len(t, elements[1].Key, int(tt.af.addrLen), "interval-end key must be a zero address, not empty")
+		})
+	}
+}

client/firewall/nftables/ipsetstore_linux.go

@@ -1,85 +0,0 @@
-package nftables
-
-import (
-	"net"
-)
-
-type ipsetStore struct {
-	ipsetReference map[string]int
-	ipsets         map[string]map[string]struct{} // ipsetName -> list of ips
-}
-
-func newIpsetStore() *ipsetStore {
-	return &ipsetStore{
-		ipsetReference: make(map[string]int),
-		ipsets:         make(map[string]map[string]struct{}),
-	}
-}
-
-func (s *ipsetStore) ips(ipsetName string) (map[string]struct{}, bool) {
-	r, ok := s.ipsets[ipsetName]
-	return r, ok
-}
-
-func (s *ipsetStore) newIpset(ipsetName string) map[string]struct{} {
-	s.ipsetReference[ipsetName] = 0
-	ipList := make(map[string]struct{})
-	s.ipsets[ipsetName] = ipList
-	return ipList
-}
-
-func (s *ipsetStore) deleteIpset(ipsetName string) {
-	delete(s.ipsetReference, ipsetName)
-	delete(s.ipsets, ipsetName)
-}
-
-func (s *ipsetStore) DeleteIpFromSet(ipsetName string, ip net.IP) {
-	ipList, ok := s.ipsets[ipsetName]
-	if !ok {
-		return
-	}
-	delete(ipList, ip.String())
-}
-
-func (s *ipsetStore) AddIpToSet(ipsetName string, ip net.IP) {
-	ipList, ok := s.ipsets[ipsetName]
-	if !ok {
-		return
-	}
-	ipList[ip.String()] = struct{}{}
-}
-
-func (s *ipsetStore) IsIpInSet(ipsetName string, ip net.IP) bool {
-	ipList, ok := s.ipsets[ipsetName]
-	if !ok {
-		return false
-	}
-	_, ok = ipList[ip.String()]
-	return ok
-}
-
-func (s *ipsetStore) AddReferenceToIpset(ipsetName string) {
-	s.ipsetReference[ipsetName]++
-}
-
-func (s *ipsetStore) DeleteReferenceFromIpSet(ipsetName string) {
-	r, ok := s.ipsetReference[ipsetName]
-	if !ok {
-		return
-	}
-	if r == 0 {
-		return
-	}
-	s.ipsetReference[ipsetName]--
-}
-
-func (s *ipsetStore) HasReferenceToSet(ipsetName string) bool {
-	if _, ok := s.ipsetReference[ipsetName]; !ok {
-		return false
-	}
-	if s.ipsetReference[ipsetName] == 0 {
-		return false
-	}
-
-	return true
-}

client/firewall/nftables/manager_linux.go

@@ -3,7 +3,6 @@ package nftables
 import (
 	"context"
 	"fmt"
-	"net"
 	"net/netip"
 	"os"
 	"sync"
@@ -45,18 +44,17 @@ type iFaceMapper interface {
 	Address() wgaddr.Address
 }
 
-// Manager of iptables firewall
+// Manager of nftables firewall. Per-family state (peer ACLs, route
+// ACLs, NAT, DNAT, MSS clamping) lives on family; Manager dispatches
+// by family and provides the public firewall.Manager surface.
 type Manager struct {
 	mutex   sync.Mutex
 	rConn   *nftables.Conn
 	wgIface iFaceMapper
 
-	router     *router
-	aclManager *AclManager
-
-	// IPv6 counterparts, nil when no v6 overlay
-	router6     *router
-	aclManager6 *AclManager
+	family4 *family
+	// IPv6 counterpart, nil when no v6 overlay.
+	family6 *family
 
 	notrackOutputChain     *nftables.Chain
 	notrackPreroutingChain *nftables.Chain
@@ -75,14 +73,9 @@ func Create(wgIface iFaceMapper, mtu uint16) (*Manager, error) {
 	workTable := &nftables.Table{Name: tableName, Family: nftables.TableFamilyIPv4}
 
 	var err error
-	m.router, err = newRouter(workTable, wgIface, mtu)
+	m.family4, err = newFamily(workTable, wgIface, mtu)
 	if err != nil {
-		return nil, fmt.Errorf("create router: %w", err)
-	}
-
-	m.aclManager, err = newAclManager(workTable, wgIface, chainNameRoutingFw)
-	if err != nil {
-		return nil, fmt.Errorf("create acl manager: %w", err)
+		return nil, fmt.Errorf("create family: %w", err)
 	}
 
 	if wgIface.Address().HasIPv6() {
@@ -100,26 +93,21 @@ func (m *Manager) createIPv6Components(tableName string, wgIface iFaceMapper, mt
 	workTable6 := &nftables.Table{Name: tableName, Family: nftables.TableFamilyIPv6}
 
 	var err error
-	m.router6, err = newRouter(workTable6, wgIface, mtu)
+	m.family6, err = newFamily(workTable6, wgIface, mtu)
 	if err != nil {
-		return fmt.Errorf("create v6 router: %w", err)
+		return fmt.Errorf("create v6 family: %w", err)
 	}
 
 	// Share the same IP forwarding state with the v4 router, since
 	// EnableIPForwarding controls both v4 and v6 sysctls.
-	m.router6.ipFwdState = m.router.ipFwdState
-
-	m.aclManager6, err = newAclManager(workTable6, wgIface, chainNameRoutingFw)
-	if err != nil {
-		return fmt.Errorf("create v6 acl manager: %w", err)
-	}
+	m.family6.ipFwdState = m.family4.ipFwdState
 
 	return nil
 }
 
 // hasIPv6 reports whether the manager has IPv6 components initialized.
 func (m *Manager) hasIPv6() bool {
-	return m.router6 != nil
+	return m.family6 != nil
 }
 
 func (m *Manager) initIPv6() error {
@@ -128,12 +116,8 @@ func (m *Manager) initIPv6() error {
 		return fmt.Errorf("create v6 work table: %w", err)
 	}
 
-	if err := m.router6.init(workTable6); err != nil {
-		return fmt.Errorf("v6 router init: %w", err)
-	}
-
-	if err := m.aclManager6.init(workTable6); err != nil {
-		return fmt.Errorf("v6 acl manager init: %w", err)
+	if err := m.family6.init(workTable6); err != nil {
+		return fmt.Errorf("v6 family init: %w", err)
 	}
 
 	return nil
@@ -162,13 +146,13 @@ func (m *Manager) reconcileExternalChains() error {
 	defer m.mutex.Unlock()
 
 	var merr *multierror.Error
-	if m.router != nil {
-		if err := m.router.acceptExternalChainsRules(); err != nil {
+	if m.family4 != nil {
+		if err := m.family4.acceptExternalChainsRules(); err != nil {
 			merr = multierror.Append(merr, fmt.Errorf("v4: %w", err))
 		}
 	}
 	if m.hasIPv6() {
-		if err := m.router6.acceptExternalChainsRules(); err != nil {
+		if err := m.family6.acceptExternalChainsRules(); err != nil {
 			merr = multierror.Append(merr, fmt.Errorf("v6: %w", err))
 		}
 	}
@@ -187,12 +171,8 @@ func (m *Manager) initFirewall() (err error) {
 		}
 	}()
 
-	if err := m.router.init(workTable); err != nil {
-		return fmt.Errorf("router init: %w", err)
-	}
-
-	if err := m.aclManager.init(workTable); err != nil {
-		return fmt.Errorf("acl manager init: %w", err)
+	if err := m.family4.init(workTable); err != nil {
+		return fmt.Errorf("family init: %w", err)
 	}
 
 	if m.hasIPv6() {
@@ -220,7 +200,7 @@ func (m *Manager) persistState(stateManager *statemanager.Manager) {
 		InterfaceState: &InterfaceState{
 			NameStr:   m.wgIface.Name(),
 			WGAddress: m.wgIface.Address(),
-			MTU:       m.router.mtu,
+			MTU:       m.family4.mtu,
 		},
 	}); err != nil {
 		log.Errorf("failed to update state: %v", err)
@@ -235,12 +215,12 @@ func (m *Manager) persistState(stateManager *statemanager.Manager) {
 
 // rollbackInit performs best-effort cleanup of already-initialized state when Init fails partway through.
 func (m *Manager) rollbackInit() {
-	if err := m.router.Reset(); err != nil {
-		log.Warnf("rollback router: %v", err)
+	if err := m.family4.Reset(); err != nil {
+		log.Warnf("rollback family: %v", err)
 	}
 	if m.hasIPv6() {
-		if err := m.router6.Reset(); err != nil {
-			log.Warnf("rollback v6 router: %v", err)
+		if err := m.family6.Reset(); err != nil {
+			log.Warnf("rollback v6 family: %v", err)
 		}
 	}
 	if err := m.cleanupNetbirdTables(); err != nil {
@@ -251,118 +231,77 @@ func (m *Manager) rollbackInit() {
 	}
 }
 
-// AddPeerFiltering rule to the firewall
+// AddFilterRule installs a packet-filtering rule.
 //
-// If comment argument is empty firewall manager should set
-// rule ID as comment for the rule
-func (m *Manager) AddPeerFiltering(
-	id []byte,
-	ip net.IP,
-	proto firewall.Protocol,
-	sPort *firewall.Port,
-	dPort *firewall.Port,
-	action firewall.Action,
-	ipsetName string,
-) ([]firewall.Rule, error) {
-	m.mutex.Lock()
-	defer m.mutex.Unlock()
-
-	if ip.To4() != nil {
-		return m.aclManager.AddPeerFiltering(id, ip, proto, sPort, dPort, action, ipsetName)
-	}
-
-	if !m.hasIPv6() {
-		return nil, fmt.Errorf("add peer filtering for %s: %w", ip, firewall.ErrIPv6NotInitialized)
-	}
-	return m.aclManager6.AddPeerFiltering(id, ip, proto, sPort, dPort, action, ipsetName)
-}
-
-func (m *Manager) AddRouteFiltering(
+// Destination semantics: zero Network → input chain (peer ACL);
+// set Network → forward chain (route ACL).
+//
+// Sources are a single address family; the rule is dispatched to the
+// matching per-family backend.
+func (m *Manager) AddFilterRule(
 	id []byte,
 	sources []netip.Prefix,
 	destination firewall.Network,
 	proto firewall.Protocol,
-	sPort, dPort *firewall.Port,
+	sPort *firewall.Port,
+	dPort *firewall.Port,
 	action firewall.Action,
 ) (firewall.Rule, error) {
+	if len(sources) == 0 {
+		return nil, firewall.ErrNoSources
+	}
+
 	m.mutex.Lock()
 	defer m.mutex.Unlock()
 
-	if isIPv6RouteRule(sources, destination) {
+	fam := m.family4
+	if isIPv6Rule(sources, destination) {
 		if !m.hasIPv6() {
-			return nil, fmt.Errorf("add route filtering: %w", firewall.ErrIPv6NotInitialized)
+			return nil, fmt.Errorf("add filtering: %w", firewall.ErrIPv6NotInitialized)
 		}
-		return m.router6.AddRouteFiltering(id, sources, destination, proto, sPort, dPort, action)
+		fam = m.family6
 	}
-
-	return m.router.AddRouteFiltering(id, sources, destination, proto, sPort, dPort, action)
+	return fam.AddFilterRule(id, sources, destination, proto, sPort, dPort, action)
 }
 
-// DeletePeerRule from the firewall by rule definition
-func (m *Manager) DeletePeerRule(rule firewall.Rule) error {
+// DeleteFilterRule removes a filtering rule. The owning family is found
+// by id, refreshing from the kernel if the in-memory caches miss so a
+// stale cache cannot leak the rule. family.DeleteFilterRule is idempotent
+// when the id is absent.
+func (m *Manager) DeleteFilterRule(rule firewall.Rule) error {
 	m.mutex.Lock()
 	defer m.mutex.Unlock()
 
-	if m.hasIPv6() && isIPv6Rule(rule) {
-		return m.aclManager6.DeletePeerRule(rule)
-	}
-	return m.aclManager.DeletePeerRule(rule)
-}
-
-func isIPv6Rule(rule firewall.Rule) bool {
-	r, ok := rule.(*Rule)
-	return ok && r.nftRule != nil && r.nftRule.Table != nil && r.nftRule.Table.Family == nftables.TableFamilyIPv6
-}
-
-// isIPv6RouteRule determines whether a route rule belongs to the v6 table.
-// For static routes, the destination prefix determines the family. For dynamic
-// routes (DomainSet), the sources determine the family since management
-// duplicates dynamic rules per family.
-func isIPv6RouteRule(sources []netip.Prefix, destination firewall.Network) bool {
-	if destination.IsPrefix() {
-		return destination.Prefix.Addr().Is6()
-	}
-	return len(sources) > 0 && sources[0].Addr().Is6()
-}
-
-// DeleteRouteRule deletes a routing rule. Route rules live in exactly one
-// router; the cached maps are normally authoritative, so the kernel is only
-// consulted when neither map knows about the rule.
-func (m *Manager) DeleteRouteRule(rule firewall.Rule) error {
-	m.mutex.Lock()
-	defer m.mutex.Unlock()
-
-	id := rule.ID()
-	r, err := m.routerForRuleID(id, (*router).hasRule)
+	fam, err := m.familyForRuleID(rule.ID(), (*family).hasRule)
 	if err != nil {
 		return err
 	}
-	return r.DeleteRouteRule(rule)
+	return fam.DeleteFilterRule(rule)
 }
 
-// routerForRuleID picks the router holding the rule with the given id, using
+// familyForRuleID picks the family holding the rule with the given id, using
 // the supplied lookup. If the cached maps disagree (or both miss), it refreshes
-// from the kernel once and re-checks before falling back to the v4 router.
-func (m *Manager) routerForRuleID(id string, has func(*router, string) bool) (*router, error) {
-	if has(m.router, id) {
-		return m.router, nil
+// from the kernel once and re-checks before falling back to the v4 family.
+func (m *Manager) familyForRuleID(id firewall.RuleID, has func(*family, firewall.RuleID) bool) (*family, error) {
+	if has(m.family4, id) {
+		return m.family4, nil
 	}
-	if m.hasIPv6() && has(m.router6, id) {
-		return m.router6, nil
+	if m.hasIPv6() && has(m.family6, id) {
+		return m.family6, nil
 	}
 	if !m.hasIPv6() {
-		return m.router, nil
+		return m.family4, nil
 	}
-	if err := m.router.refreshRulesMap(); err != nil {
+	if err := m.family4.refreshRulesMap(); err != nil {
 		return nil, fmt.Errorf("refresh v4 rules: %w", err)
 	}
-	if err := m.router6.refreshRulesMap(); err != nil {
+	if err := m.family6.refreshRulesMap(); err != nil {
 		return nil, fmt.Errorf("refresh v6 rules: %w", err)
 	}
-	if has(m.router6, id) && !has(m.router, id) {
-		return m.router6, nil
+	if has(m.family6, id) && !has(m.family4, id) {
+		return m.family6, nil
 	}
-	return m.router, nil
+	return m.family4, nil
 }
 
 func (m *Manager) IsServerRouteSupported() bool {
@@ -381,10 +320,10 @@ func (m *Manager) AddNatRule(pair firewall.RouterPair) error {
 		if !m.hasIPv6() {
 			return fmt.Errorf("add NAT rule: %w", firewall.ErrIPv6NotInitialized)
 		}
-		return m.router6.AddNatRule(pair)
+		return m.family6.AddNatRule(pair)
 	}
 
-	if err := m.router.AddNatRule(pair); err != nil {
+	if err := m.family4.AddNatRule(pair); err != nil {
 		return err
 	}
 
@@ -396,7 +335,7 @@ func (m *Manager) AddNatRule(pair firewall.RouterPair) error {
 	// so the eventual cleanup still works.
 	if m.hasIPv6() && pair.Dynamic {
 		v6Pair := firewall.ToV6NatPair(pair)
-		if err := m.router6.AddNatRule(v6Pair); err != nil {
+		if err := m.family6.AddNatRule(v6Pair); err != nil {
 			return fmt.Errorf("add v6 NAT rule: %w", err)
 		}
 	}
@@ -412,18 +351,18 @@ func (m *Manager) RemoveNatRule(pair firewall.RouterPair) error {
 		if !m.hasIPv6() {
 			return nil
 		}
-		return m.router6.RemoveNatRule(pair)
+		return m.family6.RemoveNatRule(pair)
 	}
 
 	var merr *multierror.Error
 
-	if err := m.router.RemoveNatRule(pair); err != nil {
+	if err := m.family4.RemoveNatRule(pair); err != nil {
 		merr = multierror.Append(merr, fmt.Errorf("remove v4 NAT rule: %w", err))
 	}
 
 	if m.hasIPv6() && pair.Dynamic {
 		v6Pair := firewall.ToV6NatPair(pair)
-		if err := m.router6.RemoveNatRule(v6Pair); err != nil {
+		if err := m.family6.RemoveNatRule(v6Pair); err != nil {
 			merr = multierror.Append(merr, fmt.Errorf("remove v6 NAT rule: %w", err))
 		}
 	}
@@ -445,11 +384,11 @@ func (m *Manager) AllowNetbird() error {
 	m.mutex.Lock()
 	defer m.mutex.Unlock()
 
-	if err := m.aclManager.createDefaultAllowRules(); err != nil {
+	if err := m.family4.createDefaultAllowRules(); err != nil {
 		return fmt.Errorf("create default allow rules: %w", err)
 	}
 	if m.hasIPv6() {
-		if err := m.aclManager6.createDefaultAllowRules(); err != nil {
+		if err := m.family6.createDefaultAllowRules(); err != nil {
 			return fmt.Errorf("create v6 default allow rules: %w", err)
 		}
 	}
@@ -466,11 +405,11 @@ func (m *Manager) AllowNetbird() error {
 
 // SetLegacyManagement sets the route manager to use legacy management
 func (m *Manager) SetLegacyManagement(isLegacy bool) error {
-	if err := firewall.SetLegacyManagement(m.router, isLegacy); err != nil {
+	if err := firewall.SetLegacyManagement(m.family4, isLegacy); err != nil {
 		return err
 	}
 	if m.hasIPv6() {
-		return firewall.SetLegacyManagement(m.router6, isLegacy)
+		return firewall.SetLegacyManagement(m.family6, isLegacy)
 	}
 	return nil
 }
@@ -484,13 +423,13 @@ func (m *Manager) Close(stateManager *statemanager.Manager) error {
 
 	var merr *multierror.Error
 
-	if err := m.router.Reset(); err != nil {
-		merr = multierror.Append(merr, fmt.Errorf("reset router: %v", err))
+	if err := m.family4.Reset(); err != nil {
+		merr = multierror.Append(merr, fmt.Errorf("reset family: %w", err))
 	}
 
 	if m.hasIPv6() {
-		if err := m.router6.Reset(); err != nil {
-			merr = multierror.Append(merr, fmt.Errorf("reset v6 router: %v", err))
+		if err := m.family6.Reset(); err != nil {
+			merr = multierror.Append(merr, fmt.Errorf("reset v6 family: %w", err))
 		}
 	}
 
@@ -530,14 +469,14 @@ func (m *Manager) SetLogLevel(log.Level) {
 }
 
 func (m *Manager) EnableRouting() error {
-	if err := m.router.ipFwdState.RequestForwarding(); err != nil {
+	if err := m.family4.ipFwdState.RequestForwarding(); err != nil {
 		return fmt.Errorf("enable IP forwarding: %w", err)
 	}
 	return nil
 }
 
 func (m *Manager) DisableRouting() error {
-	if err := m.router.ipFwdState.ReleaseForwarding(); err != nil {
+	if err := m.family4.ipFwdState.ReleaseForwarding(); err != nil {
 		return fmt.Errorf("disable IP forwarding: %w", err)
 	}
 	return nil
@@ -551,12 +490,12 @@ func (m *Manager) Flush() error {
 	m.mutex.Lock()
 	defer m.mutex.Unlock()
 
-	if err := m.aclManager.Flush(); err != nil {
+	if err := m.family4.Flush(); err != nil {
 		return err
 	}
 
 	if m.hasIPv6() {
-		if err := m.aclManager6.Flush(); err != nil {
+		if err := m.family6.Flush(); err != nil {
 			return fmt.Errorf("flush v6 acl: %w", err)
 		}
 	}
@@ -577,9 +516,9 @@ func (m *Manager) AddDNATRule(rule firewall.ForwardRule) (firewall.Rule, error)
 		if !m.hasIPv6() {
 			return nil, fmt.Errorf("add DNAT rule: %w", firewall.ErrIPv6NotInitialized)
 		}
-		return m.router6.AddDNATRule(rule)
+		return m.family6.AddDNATRule(rule)
 	}
-	return m.router.AddDNATRule(rule)
+	return m.family4.AddDNATRule(rule)
 }
 
 // DeleteDNATRule deletes a DNAT rule
@@ -587,7 +526,7 @@ func (m *Manager) DeleteDNATRule(rule firewall.Rule) error {
 	m.mutex.Lock()
 	defer m.mutex.Unlock()
 
-	r, err := m.routerForRuleID(rule.ID(), (*router).hasDNATRule)
+	r, err := m.familyForRuleID(rule.ID(), (*family).hasDNATRule)
 	if err != nil {
 		return err
 	}
@@ -608,12 +547,12 @@ func (m *Manager) UpdateSet(set firewall.Set, prefixes []netip.Prefix) error {
 		}
 	}
 
-	if err := m.router.UpdateSet(set, v4Prefixes); err != nil {
+	if err := m.family4.UpdateSet(set, v4Prefixes); err != nil {
 		return err
 	}
 
 	if m.hasIPv6() && len(v6Prefixes) > 0 {
-		if err := m.router6.UpdateSet(set, v6Prefixes); err != nil {
+		if err := m.family6.UpdateSet(set, v6Prefixes); err != nil {
 			return fmt.Errorf("update v6 set: %w", err)
 		}
 	}
@@ -630,9 +569,9 @@ func (m *Manager) AddInboundDNAT(localAddr netip.Addr, protocol firewall.Protoco
 		if !m.hasIPv6() {
 			return fmt.Errorf("add inbound DNAT: %w", firewall.ErrIPv6NotInitialized)
 		}
-		return m.router6.AddInboundDNAT(localAddr, protocol, originalPort, translatedPort)
+		return m.family6.AddInboundDNAT(localAddr, protocol, originalPort, translatedPort)
 	}
-	return m.router.AddInboundDNAT(localAddr, protocol, originalPort, translatedPort)
+	return m.family4.AddInboundDNAT(localAddr, protocol, originalPort, translatedPort)
 }
 
 // RemoveInboundDNAT removes an inbound DNAT rule.
@@ -644,9 +583,9 @@ func (m *Manager) RemoveInboundDNAT(localAddr netip.Addr, protocol firewall.Prot
 		if !m.hasIPv6() {
 			return fmt.Errorf("remove inbound DNAT: %w", firewall.ErrIPv6NotInitialized)
 		}
-		return m.router6.RemoveInboundDNAT(localAddr, protocol, originalPort, translatedPort)
+		return m.family6.RemoveInboundDNAT(localAddr, protocol, originalPort, translatedPort)
 	}
-	return m.router.RemoveInboundDNAT(localAddr, protocol, originalPort, translatedPort)
+	return m.family4.RemoveInboundDNAT(localAddr, protocol, originalPort, translatedPort)
 }
 
 // AddOutputDNAT adds an OUTPUT chain DNAT rule for locally-generated traffic.
@@ -658,9 +597,9 @@ func (m *Manager) AddOutputDNAT(localAddr netip.Addr, protocol firewall.Protocol
 		if !m.hasIPv6() {
 			return fmt.Errorf("add output DNAT: %w", firewall.ErrIPv6NotInitialized)
 		}
-		return m.router6.AddOutputDNAT(localAddr, protocol, originalPort, translatedPort)
+		return m.family6.AddOutputDNAT(localAddr, protocol, originalPort, translatedPort)
 	}
-	return m.router.AddOutputDNAT(localAddr, protocol, originalPort, translatedPort)
+	return m.family4.AddOutputDNAT(localAddr, protocol, originalPort, translatedPort)
 }
 
 // RemoveOutputDNAT removes an OUTPUT chain DNAT rule.
@@ -672,9 +611,9 @@ func (m *Manager) RemoveOutputDNAT(localAddr netip.Addr, protocol firewall.Proto
 		if !m.hasIPv6() {
 			return fmt.Errorf("remove output DNAT: %w", firewall.ErrIPv6NotInitialized)
 		}
-		return m.router6.RemoveOutputDNAT(localAddr, protocol, originalPort, translatedPort)
+		return m.family6.RemoveOutputDNAT(localAddr, protocol, originalPort, translatedPort)
 	}
-	return m.router.RemoveOutputDNAT(localAddr, protocol, originalPort, translatedPort)
+	return m.family4.RemoveOutputDNAT(localAddr, protocol, originalPort, translatedPort)
 }
 
 const (
@@ -903,3 +842,14 @@ func getEstablishedExprs(register uint32) []expr.Any {
 		},
 	}
 }
+
+// isIPv6Rule reports whether the rule belongs to the v6 table. For a
+// prefix destination the destination family decides; otherwise the
+// (single-family) sources do, since management duplicates rules per
+// family.
+func isIPv6Rule(sources []netip.Prefix, destination firewall.Network) bool {
+	if destination.IsPrefix() {
+		return destination.Prefix.Addr().Is6()
+	}
+	return len(sources) > 0 && sources[0].Addr().Is6()
+}

client/firewall/nftables/manager_linux_test.go

@@ -1,3 +1,5 @@
+//go:build integration && !android
+
 package nftables
 
 import (
@@ -70,13 +72,13 @@ func TestNftablesManager(t *testing.T) {
 
 	testClient := &nftables.Conn{}
 
-	rule, err := manager.AddPeerFiltering(nil, ip.AsSlice(), fw.ProtocolTCP, nil, &fw.Port{Values: []uint16{53}}, fw.ActionDrop, "")
+	rule, err := manager.AddFilterRule(nil, pfx(ip.AsSlice()), fw.Network{}, fw.ProtocolTCP, nil, &fw.Port{Values: []uint16{53}}, fw.ActionDrop)
 	require.NoError(t, err, "failed to add rule")
 
 	err = manager.Flush()
 	require.NoError(t, err, "failed to flush")
 
-	rules, err := testClient.GetRules(manager.aclManager.workTable, manager.aclManager.chainInputRules)
+	rules, err := testClient.GetRules(manager.family4.workTable, manager.family4.chainInputRules)
 	require.NoError(t, err, "failed to get rules")
 
 	require.Len(t, rules, 2, "expected 2 rules")
@@ -147,15 +149,12 @@ func TestNftablesManager(t *testing.T) {
 	// Compare connection tracking rule at position 1 (pushed down by DROP rule insertion)
 	compareExprsIgnoringCounters(t, rules[1].Exprs, expectedExprs1)
 
-	for _, r := range rule {
-		err = manager.DeletePeerRule(r)
-		require.NoError(t, err, "failed to delete rule")
-	}
+	require.NoError(t, manager.DeleteFilterRule(rule), "failed to delete rule")
 
 	err = manager.Flush()
 	require.NoError(t, err, "failed to flush")
 
-	rules, err = testClient.GetRules(manager.aclManager.workTable, manager.aclManager.chainInputRules)
+	rules, err = testClient.GetRules(manager.family4.workTable, manager.family4.chainInputRules)
 	require.NoError(t, err, "failed to get rules")
 	// established rule remains
 	require.Len(t, rules, 1, "expected 1 rules after deletion")
@@ -180,47 +179,39 @@ func TestNftablesManagerRuleOrder(t *testing.T) {
 	testClient := &nftables.Conn{}
 
 	// Add accept rule first
-	_, err = manager.AddPeerFiltering(nil, ip.AsSlice(), fw.ProtocolTCP, nil, &fw.Port{Values: []uint16{80}}, fw.ActionAccept, "accept-http")
+	_, err = manager.AddFilterRule(nil, pfx(ip.AsSlice()), fw.Network{}, fw.ProtocolTCP, nil, &fw.Port{Values: []uint16{80}}, fw.ActionAccept)
 	require.NoError(t, err, "failed to add accept rule")
 
 	// Add deny rule second for the same traffic
-	_, err = manager.AddPeerFiltering(nil, ip.AsSlice(), fw.ProtocolTCP, nil, &fw.Port{Values: []uint16{80}}, fw.ActionDrop, "deny-http")
+	_, err = manager.AddFilterRule(nil, pfx(ip.AsSlice()), fw.Network{}, fw.ProtocolTCP, nil, &fw.Port{Values: []uint16{80}}, fw.ActionDrop)
 	require.NoError(t, err, "failed to add deny rule")
 
 	err = manager.Flush()
 	require.NoError(t, err, "failed to flush")
 
-	rules, err := testClient.GetRules(manager.aclManager.workTable, manager.aclManager.chainInputRules)
+	rules, err := testClient.GetRules(manager.family4.workTable, manager.family4.chainInputRules)
 	require.NoError(t, err, "failed to get rules")
 
 	t.Logf("Found %d rules in nftables chain", len(rules))
 
-	// Find the accept and deny rules and verify deny comes before accept
+	// Single-source rules emit a direct payload+cmp on the source IP
+	// (no set lookup). Match by source-IP + port + verdict instead of
+	// the legacy per-(action,port) set names ("deny-http"/"accept-http")
+	// that this test predates.
+	wantSrc := ip.AsSlice()
 	var acceptRuleIndex, denyRuleIndex = -1, -1
 	for i, rule := range rules {
-		hasAcceptHTTPSet := false
-		hasDenyHTTPSet := false
-		hasPort80 := false
+		var hasSrc, hasPort80 bool
 		var action string
-
 		for _, e := range rule.Exprs {
-			// Check for set lookup
-			if lookup, ok := e.(*expr.Lookup); ok {
-				switch lookup.SetName {
-				case "accept-http":
-					hasAcceptHTTPSet = true
-				case "deny-http":
-					hasDenyHTTPSet = true
+			if cmp, ok := e.(*expr.Cmp); ok && cmp.Op == expr.CmpOpEq {
+				if bytes.Equal(cmp.Data, wantSrc) {
+					hasSrc = true
 				}
-
-			}
-			// Check for port 80
-			if cmp, ok := e.(*expr.Cmp); ok {
-				if cmp.Op == expr.CmpOpEq && len(cmp.Data) == 2 && binary.BigEndian.Uint16(cmp.Data) == 80 {
+				if len(cmp.Data) == 2 && binary.BigEndian.Uint16(cmp.Data) == 80 {
 					hasPort80 = true
 				}
 			}
-			// Check for verdict
 			if verdict, ok := e.(*expr.Verdict); ok {
 				switch verdict.Kind {
 				case expr.VerdictAccept:
@@ -231,11 +222,15 @@ func TestNftablesManagerRuleOrder(t *testing.T) {
 			}
 		}
 
-		if hasAcceptHTTPSet && hasPort80 && action == "ACCEPT" {
-			t.Logf("Rule [%d]: accept-http set + Port 80 + ACCEPT", i)
+		if !hasSrc || !hasPort80 {
+			continue
+		}
+		switch action {
+		case "ACCEPT":
+			t.Logf("Rule [%d]: src=%s port=80 ACCEPT", i, ip)
 			acceptRuleIndex = i
-		} else if hasDenyHTTPSet && hasPort80 && action == "DROP" {
-			t.Logf("Rule [%d]: deny-http set + Port 80 + DROP", i)
+		case "DROP":
+			t.Logf("Rule [%d]: src=%s port=80 DROP", i, ip)
 			denyRuleIndex = i
 		}
 	}
@@ -279,7 +274,7 @@ func TestNFtablesCreatePerformance(t *testing.T) {
 			start := time.Now()
 			for i := 0; i < testMax; i++ {
 				port := &fw.Port{Values: []uint16{uint16(1000 + i)}}
-				_, err = manager.AddPeerFiltering(nil, ip.AsSlice(), "tcp", nil, port, fw.ActionAccept, "")
+				_, err = manager.AddFilterRule(nil, pfx(ip.AsSlice()), fw.Network{}, "tcp", nil, port, fw.ActionAccept)
 				require.NoError(t, err, "failed to add rule")
 
 				if i%100 == 0 {
@@ -361,10 +356,10 @@ func TestNftablesManagerCompatibilityWithIptables(t *testing.T) {
 	})
 
 	ip := netip.MustParseAddr("100.96.0.1")
-	_, err = manager.AddPeerFiltering(nil, ip.AsSlice(), fw.ProtocolTCP, nil, &fw.Port{Values: []uint16{80}}, fw.ActionAccept, "")
+	_, err = manager.AddFilterRule(nil, pfx(ip.AsSlice()), fw.Network{}, fw.ProtocolTCP, nil, &fw.Port{Values: []uint16{80}}, fw.ActionAccept)
 	require.NoError(t, err, "failed to add peer filtering rule")
 
-	_, err = manager.AddRouteFiltering(
+	_, err = manager.AddFilterRule(
 		nil,
 		[]netip.Prefix{netip.MustParsePrefix("192.168.2.0/24")},
 		fw.Network{Prefix: netip.MustParsePrefix("10.1.0.0/24")},
@@ -437,10 +432,10 @@ func TestNftablesManagerIPv6CompatibilityWithIp6tables(t *testing.T) {
 	})
 
 	ip := netip.MustParseAddr("fd00::2")
-	_, err = manager.AddPeerFiltering(nil, ip.AsSlice(), fw.ProtocolTCP, nil, &fw.Port{Values: []uint16{80}}, fw.ActionAccept, "")
+	_, err = manager.AddFilterRule(nil, pfx(ip.AsSlice()), fw.Network{}, fw.ProtocolTCP, nil, &fw.Port{Values: []uint16{80}}, fw.ActionAccept)
 	require.NoError(t, err, "add v6 peer filtering rule")
 
-	_, err = manager.AddRouteFiltering(
+	_, err = manager.AddFilterRule(
 		nil,
 		[]netip.Prefix{netip.MustParsePrefix("fd00:1::/64")},
 		fw.Network{Prefix: netip.MustParsePrefix("2001:db8::/48")},
@@ -550,7 +545,7 @@ func TestNftablesManagerCompatibilityWithIptablesFor6kPrefixes(t *testing.T) {
 			prefixes = append(prefixes, netip.PrefixFrom(addr, 24))
 		}
 	}
-	_, err = manager.AddRouteFiltering(
+	_, err = manager.AddFilterRule(
 		nil,
 		prefixes,
 		fw.Network{Prefix: netip.MustParsePrefix("10.2.0.0/24")},
@@ -565,7 +560,7 @@ func TestNftablesManagerCompatibilityWithIptablesFor6kPrefixes(t *testing.T) {
 	verifyIptablesOutput(t, stdout, stderr)
 }
 
-func TestNftablesManagerCompatibilityWithIptablesForEmptyPrefixes(t *testing.T) {
+func TestNftablesManagerCompatibilityWithIptablesForWildcardSource(t *testing.T) {
 	if check() != NFTABLES {
 		t.Skip("nftables not supported on this system")
 	}
@@ -591,9 +586,9 @@ func TestNftablesManagerCompatibilityWithIptablesForEmptyPrefixes(t *testing.T)
 		verifyIptablesOutput(t, stdout, stderr)
 	})
 
-	_, err = manager.AddRouteFiltering(
+	_, err = manager.AddFilterRule(
 		nil,
-		[]netip.Prefix{},
+		[]netip.Prefix{netip.MustParsePrefix("0.0.0.0/0")},
 		fw.Network{Prefix: netip.MustParsePrefix("10.2.0.0/24")},
 		fw.ProtocolTCP,
 		nil,

client/firewall/nftables/router_linux_test.go

@@ -1,4 +1,4 @@
-//go:build !android
+//go:build integration && !android
 
 package nftables
 
@@ -37,7 +37,7 @@ func TestNftablesManager_AddNatRule(t *testing.T) {
 
 	for _, testCase := range test.InsertRuleTestCases {
 		t.Run(testCase.Name, func(t *testing.T) {
-			// need fw manager to init both acl mgr and router for all chains to be present
+			// need fw manager to init both acl mgr and family for all chains to be present
 			manager, err := Create(ifaceMock, iface.DefaultMTU)
 			t.Cleanup(func() {
 				require.NoError(t, manager.Close(nil))
@@ -47,7 +47,7 @@ func TestNftablesManager_AddNatRule(t *testing.T) {
 
 			nftablesTestingClient := &nftables.Conn{}
 
-			rtr := manager.router
+			rtr := manager.family4
 			err = rtr.AddNatRule(testCase.InputPair)
 			require.NoError(t, err, "pair should be inserted")
 
@@ -90,9 +90,9 @@ func TestNftablesManager_AddNatRule(t *testing.T) {
 				}
 
 				// Build CIDR matching expressions
-				testRouter := &router{af: afIPv4}
-				sourceExp := testRouter.applyPrefix(testCase.InputPair.Source.Prefix, true)
-				destExp := testRouter.applyPrefix(testCase.InputPair.Destination.Prefix, false)
+				testRouter := &family{af: afIPv4}
+				sourceExp := prefixMatchExprs(testRouter.af, testCase.InputPair.Source.Prefix, true)
+				destExp := prefixMatchExprs(testRouter.af, testCase.InputPair.Destination.Prefix, false)
 
 				// Combine all expressions in the correct order
 				// nolint:gocritic
@@ -100,14 +100,14 @@ func TestNftablesManager_AddNatRule(t *testing.T) {
 				testingExpression = append(testingExpression, sourceExp...)
 				testingExpression = append(testingExpression, destExp...)
 
-				natRuleKey := firewall.GenKey(firewall.PreroutingFormat, testCase.InputPair)
+				natRuleKey := testCase.InputPair.GenKey(firewall.PreroutingFormat)
 				found := 0
 				for _, chain := range rtr.chains {
 					if chain.Name == chainNameManglePrerouting {
 						rules, err := nftablesTestingClient.GetRules(chain.Table, chain)
 						require.NoError(t, err, "should list rules for %s table and %s chain", chain.Table.Name, chain.Name)
 						for _, rule := range rules {
-							if len(rule.UserData) > 0 && string(rule.UserData) == natRuleKey {
+							if len(rule.UserData) > 0 && firewall.RuleID(rule.UserData) == natRuleKey {
 								// Compare expressions up to the mark setting expressions
 								require.ElementsMatchf(t, rule.Exprs[:len(testingExpression)], testingExpression, "prerouting nat rule elements should match")
 								found = 1
@@ -135,19 +135,19 @@ func TestNftablesManager_RemoveNatRule(t *testing.T) {
 			require.NoError(t, err)
 			require.NoError(t, manager.Init(nil))
 
-			rtr := manager.router
+			rtr := manager.family4
 
-			// First add the NAT rule using the router's method
+			// First add the NAT rule using the family's method
 			err = rtr.AddNatRule(testCase.InputPair)
 			require.NoError(t, err, "should add NAT rule")
 
 			// Verify the rule was added
-			natRuleKey := firewall.GenKey(firewall.PreroutingFormat, testCase.InputPair)
+			natRuleKey := testCase.InputPair.GenKey(firewall.PreroutingFormat)
 			found := false
 			rules, err := rtr.conn.GetRules(rtr.workTable, rtr.chains[chainNameManglePrerouting])
 			require.NoError(t, err, "should list rules")
 			for _, rule := range rules {
-				if len(rule.UserData) > 0 && string(rule.UserData) == natRuleKey {
+				if len(rule.UserData) > 0 && firewall.RuleID(rule.UserData) == natRuleKey {
 					found = true
 					break
 				}
@@ -163,7 +163,7 @@ func TestNftablesManager_RemoveNatRule(t *testing.T) {
 			rules, err = rtr.conn.GetRules(rtr.workTable, rtr.chains[chainNameManglePrerouting])
 			require.NoError(t, err, "should list rules after removal")
 			for _, rule := range rules {
-				if len(rule.UserData) > 0 && string(rule.UserData) == natRuleKey {
+				if len(rule.UserData) > 0 && firewall.RuleID(rule.UserData) == natRuleKey {
 					found = true
 					break
 				}
@@ -200,11 +200,11 @@ func TestRouter_AddRouteFiltering(t *testing.T) {
 
 	defer deleteWorkTable()
 
-	r, err := newRouter(workTable, ifaceMock, iface.DefaultMTU)
-	require.NoError(t, err, "Failed to create router")
+	r, err := newFamily(workTable, ifaceMock, iface.DefaultMTU)
+	require.NoError(t, err, "Failed to create family")
 	require.NoError(t, r.init(workTable))
 
-	defer func(r *router) {
+	defer func(r *family) {
 		require.NoError(t, r.Reset(), "Failed to reset rules")
 	}(r)
 
@@ -314,16 +314,16 @@ func TestRouter_AddRouteFiltering(t *testing.T) {
 
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
-			ruleKey, err := r.AddRouteFiltering(nil, tt.sources, firewall.Network{Prefix: tt.destination}, tt.proto, tt.sPort, tt.dPort, tt.action)
-			require.NoError(t, err, "AddRouteFiltering failed")
+			ruleKey, err := r.AddFilterRule(nil, tt.sources, firewall.Network{Prefix: tt.destination}, tt.proto, tt.sPort, tt.dPort, tt.action)
+			require.NoError(t, err, "AddFilterRule failed")
 
 			t.Cleanup(func() {
-				require.NoError(t, r.DeleteRouteRule(ruleKey), "Failed to delete rule")
+				require.NoError(t, r.DeleteFilterRule(ruleKey), "Failed to delete rule")
 			})
 
-			// Check if the rule is in the internal map
-			rule, ok := r.rules[ruleKey.ID()]
-			assert.True(t, ok, "Rule not found in internal map")
+			stored, ok := r.filters[id.RuleID(ruleKey.ID())]
+			require.True(t, ok, "Rule not found in filters map")
+			rule := stored.nftRule
 
 			t.Log("Internal rule expressions:")
 			for i, expr := range rule.Exprs {
@@ -339,7 +339,7 @@ func TestRouter_AddRouteFiltering(t *testing.T) {
 
 			var nftRule *nftables.Rule
 			for _, rule := range rules {
-				if string(rule.UserData) == ruleKey.ID() {
+				if firewall.RuleID(rule.UserData) == ruleKey.ID() {
 					nftRule = rule
 					break
 				}
@@ -367,12 +367,12 @@ func TestNftablesCreateIpSet(t *testing.T) {
 
 	defer deleteWorkTable()
 
-	r, err := newRouter(workTable, ifaceMock, iface.DefaultMTU)
-	require.NoError(t, err, "Failed to create router")
+	r, err := newFamily(workTable, ifaceMock, iface.DefaultMTU)
+	require.NoError(t, err, "Failed to create family")
 	require.NoError(t, r.init(workTable))
 
 	defer func() {
-		require.NoError(t, r.Reset(), "Failed to reset router")
+		require.NoError(t, r.Reset(), "Failed to reset family")
 	}()
 
 	tests := []struct {
@@ -509,6 +509,42 @@ func TestNftablesCreateIpSet(t *testing.T) {
 	}
 }
 
+// TestNftablesUpdateSetMergesOverlapping verifies that UpdateSet merges
+// overlapping prefixes before adding them. An interval set rejects
+// overlapping elements, so without the merge a batch holding a /32 already
+// covered by a /24, or a duplicate address as DNS resolution can produce,
+// would fail.
+func TestNftablesUpdateSetMergesOverlapping(t *testing.T) {
+	if check() != NFTABLES {
+		t.Skip("nftables not supported on this system")
+	}
+
+	workTable, err := createWorkTable()
+	require.NoError(t, err, "create work table")
+	defer deleteWorkTable()
+
+	r, err := newFamily(workTable, ifaceMock, iface.DefaultMTU)
+	require.NoError(t, err, "create family")
+	require.NoError(t, r.init(workTable))
+	defer func() {
+		require.NoError(t, r.Reset(), "reset family")
+	}()
+
+	initial := []netip.Prefix{netip.MustParsePrefix("10.0.0.0/24")}
+	set := firewall.NewPrefixSet(initial)
+
+	created, err := r.createIpSet(set.HashedName(), setInput{prefixes: initial})
+	require.NoError(t, err, "create ip set")
+	require.NotNil(t, created)
+
+	overlapping := []netip.Prefix{
+		netip.MustParsePrefix("192.168.1.0/24"),
+		netip.MustParsePrefix("192.168.1.1/32"),
+		netip.MustParsePrefix("192.168.1.1/32"),
+	}
+	require.NoError(t, r.UpdateSet(set, overlapping), "UpdateSet must merge overlapping prefixes")
+}
+
 func TestNftablesCreateIpSet_IPv6(t *testing.T) {
 	if check() != NFTABLES {
 		t.Skip("nftables not supported on this system")
@@ -518,11 +554,11 @@ func TestNftablesCreateIpSet_IPv6(t *testing.T) {
 	require.NoError(t, err, "Failed to create v6 work table")
 	defer deleteWorkTableIPv6()
 
-	r, err := newRouter(workTable, ifaceMock, iface.DefaultMTU)
-	require.NoError(t, err, "Failed to create router")
+	r, err := newFamily(workTable, ifaceMock, iface.DefaultMTU)
+	require.NoError(t, err, "Failed to create family")
 	require.NoError(t, r.init(workTable))
 	defer func() {
-		require.NoError(t, r.Reset(), "Failed to reset router")
+		require.NoError(t, r.Reset(), "Failed to reset family")
 	}()
 
 	tests := []struct {
@@ -861,13 +897,13 @@ func TestRouter_RefreshRulesMap_RemovesStaleEntries(t *testing.T) {
 	require.NoError(t, err)
 	defer deleteWorkTable()
 
-	r, err := newRouter(workTable, ifaceMock, iface.DefaultMTU)
+	r, err := newFamily(workTable, ifaceMock, iface.DefaultMTU)
 	require.NoError(t, err)
 	require.NoError(t, r.init(workTable))
 	defer func() { require.NoError(t, r.Reset()) }()
 
 	// Add a real rule to the kernel
-	ruleKey, err := r.AddRouteFiltering(
+	ruleKey, err := r.AddFilterRule(
 		nil,
 		[]netip.Prefix{netip.MustParsePrefix("192.168.1.0/24")},
 		firewall.Network{Prefix: netip.MustParsePrefix("10.0.0.0/24")},
@@ -878,11 +914,11 @@ func TestRouter_RefreshRulesMap_RemovesStaleEntries(t *testing.T) {
 	)
 	require.NoError(t, err)
 	t.Cleanup(func() {
-		require.NoError(t, r.DeleteRouteRule(ruleKey))
+		require.NoError(t, r.DeleteFilterRule(ruleKey))
 	})
 
 	// Inject a stale entry with Handle=0 (simulates store-before-flush failure)
-	staleKey := "stale-rule-that-does-not-exist"
+	staleKey := firewall.RuleID("stale-rule-that-does-not-exist")
 	r.rules[staleKey] = &nftables.Rule{
 		Table:    r.workTable,
 		Chain:    r.chains[chainNameRoutingFw],
@@ -902,6 +938,55 @@ func TestRouter_RefreshRulesMap_RemovesStaleEntries(t *testing.T) {
 	assert.NotZero(t, realRule.Handle, "real rule should have a valid handle")
 }
 
+// TestRouter_DeleteRouteRule_RemovesKernelRule verifies a route filter
+// rule is actually removed from the kernel on delete. The route chain is
+// not refreshed by Flush, so the stored rule carries a zero handle;
+// DeleteFilterRule must pull live handles itself before issuing the
+// delete or the kernel rule leaks. Regression test for that path.
+func TestRouter_DeleteRouteRule_RemovesKernelRule(t *testing.T) {
+	if check() != NFTABLES {
+		t.Skip("nftables not supported on this system")
+	}
+
+	workTable, err := createWorkTable()
+	require.NoError(t, err)
+	defer deleteWorkTable()
+
+	r, err := newFamily(workTable, ifaceMock, iface.DefaultMTU)
+	require.NoError(t, err)
+	require.NoError(t, r.init(workTable))
+	defer func() { require.NoError(t, r.Reset()) }()
+
+	ruleKey, err := r.AddFilterRule(
+		nil,
+		[]netip.Prefix{netip.MustParsePrefix("192.168.1.0/24")},
+		firewall.Network{Prefix: netip.MustParsePrefix("10.0.0.0/24")},
+		firewall.ProtocolTCP,
+		nil,
+		&firewall.Port{Values: []uint16{80}},
+		firewall.ActionAccept,
+	)
+	require.NoError(t, err)
+
+	countKernelRules := func() int {
+		list, err := r.conn.GetRules(r.workTable, r.chains[chainNameRoutingFw])
+		require.NoError(t, err)
+		n := 0
+		for _, rule := range list {
+			if string(rule.UserData) == string(ruleKey.ID()) {
+				n++
+			}
+		}
+		return n
+	}
+
+	require.Equal(t, 1, countKernelRules(), "rule should be present in the kernel after add")
+
+	require.NoError(t, r.DeleteFilterRule(ruleKey))
+	assert.Equal(t, 0, countKernelRules(), "rule must be removed from the kernel after delete")
+	assert.NotContains(t, r.filters, ruleKey.ID(), "filters map entry should be cleared")
+}
+
 func TestRouter_DeleteRouteRule_StaleHandle(t *testing.T) {
 	if check() != NFTABLES {
 		t.Skip("nftables not supported on this system")
@@ -911,24 +996,28 @@ func TestRouter_DeleteRouteRule_StaleHandle(t *testing.T) {
 	require.NoError(t, err)
 	defer deleteWorkTable()
 
-	r, err := newRouter(workTable, ifaceMock, iface.DefaultMTU)
+	r, err := newFamily(workTable, ifaceMock, iface.DefaultMTU)
 	require.NoError(t, err)
 	require.NoError(t, r.init(workTable))
 	defer func() { require.NoError(t, r.Reset()) }()
 
 	// Inject a stale entry with Handle=0
-	staleKey := "stale-route-rule"
-	r.rules[staleKey] = &nftables.Rule{
-		Table:    r.workTable,
-		Chain:    r.chains[chainNameRoutingFw],
-		Handle:   0,
-		UserData: []byte(staleKey),
+	staleKey := id.RuleID("stale-route-rule")
+	staleRule := &Rule{
+		nftRule: &nftables.Rule{
+			Table:    r.workTable,
+			Chain:    r.chains[chainNameRoutingFw],
+			Handle:   0,
+			UserData: []byte(staleKey),
+		},
+		id: staleKey,
 	}
+	r.filters[staleKey] = staleRule
 
-	// DeleteRouteRule should not return an error for stale handles
-	err = r.DeleteRouteRule(id.RuleID(staleKey))
+	// DeleteFilterRule should not return an error for stale handles
+	err = r.DeleteFilterRule(staleRule)
 	assert.NoError(t, err, "deleting a stale rule should not error")
-	assert.NotContains(t, r.rules, staleKey, "stale entry should be cleaned up")
+	assert.NotContains(t, r.filters, staleKey, "stale entry should be cleaned up")
 }
 
 func TestRouter_AddNatRule_WithStaleEntry(t *testing.T) {
@@ -950,7 +1039,7 @@ func TestRouter_AddNatRule_WithStaleEntry(t *testing.T) {
 		Masquerade:  true,
 	}
 
-	rtr := manager.router
+	rtr := manager.family4
 
 	// First add succeeds
 	err = rtr.AddNatRule(pair)
@@ -960,11 +1049,11 @@ func TestRouter_AddNatRule_WithStaleEntry(t *testing.T) {
 	})
 
 	// Corrupt the handle to simulate stale state
-	natRuleKey := firewall.GenKey(firewall.PreroutingFormat, pair)
+	natRuleKey := pair.GenKey(firewall.PreroutingFormat)
 	if rule, exists := rtr.rules[natRuleKey]; exists {
 		rule.Handle = 0
 	}
-	inverseKey := firewall.GenKey(firewall.PreroutingFormat, firewall.GetInversePair(pair))
+	inverseKey := firewall.GetInversePair(pair).GenKey(firewall.PreroutingFormat)
 	if rule, exists := rtr.rules[inverseKey]; exists {
 		rule.Handle = 0
 	}
@@ -979,7 +1068,7 @@ func TestRouter_AddNatRule_WithStaleEntry(t *testing.T) {
 
 	found := 0
 	for _, rule := range rules {
-		if len(rule.UserData) > 0 && string(rule.UserData) == natRuleKey {
+		if len(rule.UserData) > 0 && firewall.RuleID(rule.UserData) == natRuleKey {
 			found++
 		}
 	}
@@ -1010,7 +1099,7 @@ func TestCalculateLastIP(t *testing.T) {
 }
 
 func TestConvertPrefixesToSet_IPv6(t *testing.T) {
-	r := &router{af: afIPv6}
+	r := &family{af: afIPv6}
 	prefixes := []netip.Prefix{
 		netip.MustParsePrefix("fd00::/64"),
 		netip.MustParsePrefix("2001:db8::1/128"),

client/firewall/nftables/routing_linux.go

@@ -0,0 +1,494 @@
+//go:build !android
+
+package nftables
+
+import (
+	"fmt"
+	"strings"
+
+	"github.com/google/nftables"
+	"github.com/google/nftables/binaryutil"
+	"github.com/google/nftables/expr"
+	"github.com/hashicorp/go-multierror"
+	log "github.com/sirupsen/logrus"
+	"golang.org/x/sys/unix"
+
+	nberrors "github.com/netbirdio/netbird/client/errors"
+	firewall "github.com/netbirdio/netbird/client/firewall/manager"
+	nbnet "github.com/netbirdio/netbird/client/net"
+)
+
+func (r *family) AddNatRule(pair firewall.RouterPair) error {
+	if err := r.refreshRulesMap(); err != nil {
+		return fmt.Errorf(refreshRulesMapError, err)
+	}
+
+	if r.legacyManagement {
+		log.Warnf("This peer is connected to a NetBird Management service with an older version. Allowing all traffic for %s", pair.Destination)
+		if err := r.addLegacyRouteRule(pair); err != nil {
+			r.rollbackRules(pair)
+			return fmt.Errorf("add legacy routing rule: %w", err)
+		}
+	}
+
+	if pair.Masquerade {
+		if err := r.addNatRule(pair); err != nil {
+			r.rollbackRules(pair)
+			return fmt.Errorf("add nat rule: %w", err)
+		}
+
+		if err := r.addNatRule(firewall.GetInversePair(pair)); err != nil {
+			r.rollbackRules(pair)
+			return fmt.Errorf("add inverse nat rule: %w", err)
+		}
+	}
+
+	if err := r.conn.Flush(); err != nil {
+		r.rollbackRules(pair)
+		return fmt.Errorf("insert rules for %s: %w", pair.Destination, err)
+	}
+
+	return nil
+}
+
+// rollbackRules cleans up unflushed rules and their set counters after a flush failure.
+func (r *family) rollbackRules(pair firewall.RouterPair) {
+	keys := []firewall.RuleID{
+		pair.GenKey(firewall.ForwardingFormat),
+		pair.GenKey(firewall.PreroutingFormat),
+		firewall.GetInversePair(pair).GenKey(firewall.PreroutingFormat),
+	}
+	for _, key := range keys {
+		rule, ok := r.rules[key]
+		if !ok {
+			continue
+		}
+		if err := r.decrementSetCounter(rule); err != nil {
+			log.Warnf("rollback set counter for %s: %v", key, err)
+		}
+		delete(r.rules, key)
+	}
+}
+
+// addNatRule inserts a nftables rule to the conn client flush queue
+func (r *family) addNatRule(pair firewall.RouterPair) error {
+	sourceExp, err := r.applyNetwork(pair.Source, nil, true)
+	if err != nil {
+		return fmt.Errorf("apply source: %w", err)
+	}
+
+	destExp, err := r.applyNetwork(pair.Destination, nil, false)
+	if err != nil {
+		return fmt.Errorf("apply destination: %w", err)
+	}
+
+	op := expr.CmpOpEq
+	if pair.Inverse {
+		op = expr.CmpOpNeq
+	}
+
+	exprs := []expr.Any{
+		&expr.Meta{
+			Key:      expr.MetaKeyIIFNAME,
+			Register: 1,
+		},
+		&expr.Cmp{
+			Op:       op,
+			Register: 1,
+			Data:     ifname(r.wgIface.Name()),
+		},
+	}
+	// We only care about NEW connections to mark them and later identify them in the postrouting chain for masquerading.
+	// Masquerading will take care of the conntrack state, which means we won't need to mark established connections.
+	exprs = append(exprs, getCtNewExprs()...)
+
+	exprs = append(exprs, sourceExp...)
+	exprs = append(exprs, destExp...)
+
+	var markValue uint32 = nbnet.PreroutingFwmarkMasquerade
+	if pair.Inverse {
+		markValue = nbnet.PreroutingFwmarkMasqueradeReturn
+	}
+
+	exprs = append(exprs,
+		&expr.Immediate{
+			Register: 1,
+			Data:     binaryutil.NativeEndian.PutUint32(markValue),
+		},
+		&expr.Meta{
+			Key:            expr.MetaKeyMARK,
+			SourceRegister: true,
+			Register:       1,
+		},
+	)
+
+	ruleID := pair.GenKey(firewall.PreroutingFormat)
+
+	if _, exists := r.rules[ruleID]; exists {
+		if err := r.removeNatRule(pair); err != nil {
+			return fmt.Errorf("remove prerouting rule: %w", err)
+		}
+	}
+
+	// Ensure nat rules come first, so the mark can be overwritten.
+	// Currently overwritten by the dst-type LOCAL rules for redirected traffic.
+	r.rules[ruleID] = r.conn.InsertRule(&nftables.Rule{
+		Table:    r.workTable,
+		Chain:    r.chains[chainNameManglePrerouting],
+		Exprs:    exprs,
+		UserData: []byte(ruleID),
+	})
+
+	return nil
+}
+
+func (r *family) addPostroutingRules() {
+	// First masquerade rule for traffic coming in from WireGuard interface
+	exprs := []expr.Any{
+		// Match on the first fwmark
+		&expr.Meta{
+			Key:      expr.MetaKeyMARK,
+			Register: 1,
+		},
+		&expr.Cmp{
+			Op:       expr.CmpOpEq,
+			Register: 1,
+			Data:     binaryutil.NativeEndian.PutUint32(nbnet.PreroutingFwmarkMasquerade),
+		},
+
+		// We need to exclude the loopback interface as this changes the ebpf proxy port
+		&expr.Meta{
+			Key:      expr.MetaKeyOIFNAME,
+			Register: 1,
+		},
+		&expr.Cmp{
+			Op:       expr.CmpOpNeq,
+			Register: 1,
+			Data:     ifname("lo"),
+		},
+		&expr.Counter{},
+		&expr.Masq{},
+	}
+
+	r.conn.AddRule(&nftables.Rule{
+		Table: r.workTable,
+		Chain: r.chains[chainNameRoutingNat],
+		Exprs: exprs,
+	})
+
+	// Second masquerade rule for traffic going out through WireGuard interface
+	exprs2 := []expr.Any{
+		// Match on the second fwmark
+		&expr.Meta{
+			Key:      expr.MetaKeyMARK,
+			Register: 1,
+		},
+		&expr.Cmp{
+			Op:       expr.CmpOpEq,
+			Register: 1,
+			Data:     binaryutil.NativeEndian.PutUint32(nbnet.PreroutingFwmarkMasqueradeReturn),
+		},
+
+		// Match WireGuard interface
+		&expr.Meta{
+			Key:      expr.MetaKeyOIFNAME,
+			Register: 1,
+		},
+		&expr.Cmp{
+			Op:       expr.CmpOpEq,
+			Register: 1,
+			Data:     ifname(r.wgIface.Name()),
+		},
+		&expr.Counter{},
+		&expr.Masq{},
+	}
+
+	r.conn.AddRule(&nftables.Rule{
+		Table: r.workTable,
+		Chain: r.chains[chainNameRoutingNat],
+		Exprs: exprs2,
+	})
+}
+
+// addMSSClampingRules adds MSS clamping rules to prevent fragmentation for forwarded traffic.
+func (r *family) addMSSClampingRules() error {
+	overhead := uint16(ipv4TCPHeaderSize)
+	if r.af.tableFamily == nftables.TableFamilyIPv6 {
+		overhead = ipv6TCPHeaderSize
+	}
+	if r.mtu <= overhead {
+		log.Debugf("MTU %d too small for MSS clamping (overhead %d), skipping", r.mtu, overhead)
+		return nil
+	}
+	mss := r.mtu - overhead
+
+	exprsOut := []expr.Any{
+		&expr.Meta{
+			Key:      expr.MetaKeyOIFNAME,
+			Register: 1,
+		},
+		&expr.Cmp{
+			Op:       expr.CmpOpEq,
+			Register: 1,
+			Data:     ifname(r.wgIface.Name()),
+		},
+		&expr.Meta{
+			Key:      expr.MetaKeyL4PROTO,
+			Register: 1,
+		},
+		&expr.Cmp{
+			Op:       expr.CmpOpEq,
+			Register: 1,
+			Data:     []byte{unix.IPPROTO_TCP},
+		},
+		&expr.Payload{
+			DestRegister: 1,
+			Base:         expr.PayloadBaseTransportHeader,
+			Offset:       13,
+			Len:          1,
+		},
+		&expr.Bitwise{
+			DestRegister:   1,
+			SourceRegister: 1,
+			Len:            1,
+			Mask:           []byte{0x02},
+			Xor:            []byte{0x00},
+		},
+		&expr.Cmp{
+			Op:       expr.CmpOpNeq,
+			Register: 1,
+			Data:     []byte{0x00},
+		},
+		&expr.Counter{},
+		&expr.Exthdr{
+			DestRegister: 1,
+			Type:         2,
+			Offset:       2,
+			Len:          2,
+			Op:           expr.ExthdrOpTcpopt,
+		},
+		&expr.Cmp{
+			Op:       expr.CmpOpGt,
+			Register: 1,
+			Data:     binaryutil.BigEndian.PutUint16(uint16(mss)),
+		},
+		&expr.Immediate{
+			Register: 1,
+			Data:     binaryutil.BigEndian.PutUint16(uint16(mss)),
+		},
+		&expr.Exthdr{
+			SourceRegister: 1,
+			Type:           2,
+			Offset:         2,
+			Len:            2,
+			Op:             expr.ExthdrOpTcpopt,
+		},
+	}
+
+	r.conn.AddRule(&nftables.Rule{
+		Table: r.workTable,
+		Chain: r.chains[chainNameMangleForward],
+		Exprs: exprsOut,
+	})
+
+	return r.conn.Flush()
+}
+
+func (r *family) addLegacyRouteRule(pair firewall.RouterPair) error {
+	sourceExp, err := r.applyNetwork(pair.Source, nil, true)
+	if err != nil {
+		return fmt.Errorf("apply source: %w", err)
+	}
+
+	destExp, err := r.applyNetwork(pair.Destination, nil, false)
+	if err != nil {
+		return fmt.Errorf("apply destination: %w", err)
+	}
+
+	var exprs []expr.Any
+	exprs = append(exprs, sourceExp...)
+	exprs = append(exprs, destExp...)
+	exprs = append(exprs,
+		&expr.Counter{},
+		&expr.Verdict{Kind: expr.VerdictAccept},
+	)
+
+	ruleID := pair.GenKey(firewall.ForwardingFormat)
+
+	if _, exists := r.rules[ruleID]; exists {
+		if err := r.removeLegacyRouteRule(pair); err != nil {
+			return fmt.Errorf("remove legacy routing rule: %w", err)
+		}
+	}
+
+	r.rules[ruleID] = r.conn.AddRule(&nftables.Rule{
+		Table:    r.workTable,
+		Chain:    r.chains[chainNameRoutingFw],
+		Exprs:    exprs,
+		UserData: []byte(ruleID),
+	})
+	return nil
+}
+
+// removeLegacyRouteRule removes a legacy routing rule for mgmt servers pre route acls
+func (r *family) removeLegacyRouteRule(pair firewall.RouterPair) error {
+	ruleID := pair.GenKey(firewall.ForwardingFormat)
+
+	rule, exists := r.rules[ruleID]
+	if !exists {
+		return nil
+	}
+
+	return r.deleteLegacyRuleEntry(ruleID, rule)
+}
+
+// deleteLegacyRuleEntry removes one legacy forwarding rule and drops its
+// ipset references. It also clears stale entries that never got a handle.
+func (r *family) deleteLegacyRuleEntry(ruleID firewall.RuleID, rule *nftables.Rule) error {
+	if rule.Handle == 0 {
+		log.Warnf("legacy forwarding rule %s has no handle, removing stale entry", ruleID)
+		if err := r.decrementSetCounter(rule); err != nil {
+			log.Warnf("decrement set counter for stale rule %s: %v", ruleID, err)
+		}
+		delete(r.rules, ruleID)
+		return nil
+	}
+
+	if err := r.conn.DelRule(rule); err != nil {
+		return fmt.Errorf("remove legacy forwarding rule %s: %w", ruleID, err)
+	}
+
+	delete(r.rules, ruleID)
+
+	if err := r.decrementSetCounter(rule); err != nil {
+		return fmt.Errorf("decrement set counter: %w", err)
+	}
+
+	return nil
+}
+
+// GetLegacyManagement returns the route manager's legacy management mode
+func (r *family) GetLegacyManagement() bool {
+	return r.legacyManagement
+}
+
+// SetLegacyManagement sets the route manager to use legacy management mode
+func (r *family) SetLegacyManagement(isLegacy bool) {
+	r.legacyManagement = isLegacy
+}
+
+// RemoveAllLegacyRouteRules removes all legacy routing rules for mgmt servers pre route acls
+func (r *family) RemoveAllLegacyRouteRules() error {
+	if err := r.refreshRulesMap(); err != nil {
+		return fmt.Errorf(refreshRulesMapError, err)
+	}
+
+	var merr *multierror.Error
+	for k, rule := range r.rules {
+		if !strings.HasPrefix(string(k), firewall.ForwardingFormatPrefix) {
+			continue
+		}
+		if err := r.deleteLegacyRuleEntry(k, rule); err != nil {
+			merr = multierror.Append(merr, err)
+		}
+	}
+	return nberrors.FormatErrorOrNil(merr)
+}
+
+func (r *family) removeNatPreroutingRules() error {
+	table := &nftables.Table{
+		Name:   tableNat,
+		Family: r.af.tableFamily,
+	}
+	chain := &nftables.Chain{
+		Name:     chainNameNatPrerouting,
+		Table:    table,
+		Hooknum:  nftables.ChainHookPrerouting,
+		Priority: nftables.ChainPriorityNATDest,
+		Type:     nftables.ChainTypeNAT,
+	}
+	rules, err := r.conn.GetRules(table, chain)
+	if err != nil {
+		return fmt.Errorf("get rules from nat table: %w", err)
+	}
+
+	var merr *multierror.Error
+
+	// Delete rules that have our UserData suffix
+	for _, rule := range rules {
+		if len(rule.UserData) == 0 || !strings.HasSuffix(string(rule.UserData), string(dnatSuffix)) {
+			continue
+		}
+		if err := r.conn.DelRule(rule); err != nil {
+			merr = multierror.Append(merr, fmt.Errorf("delete rule %s: %w", rule.UserData, err))
+		}
+	}
+
+	if err := r.conn.Flush(); err != nil {
+		merr = multierror.Append(merr, fmt.Errorf(flushError, err))
+	}
+	return nberrors.FormatErrorOrNil(merr)
+}
+
+func (r *family) RemoveNatRule(pair firewall.RouterPair) error {
+	if err := r.refreshRulesMap(); err != nil {
+		return fmt.Errorf(refreshRulesMapError, err)
+	}
+
+	var merr *multierror.Error
+
+	if pair.Masquerade {
+		if err := r.removeNatRule(pair); err != nil {
+			merr = multierror.Append(merr, fmt.Errorf("remove prerouting rule: %w", err))
+		}
+
+		if err := r.removeNatRule(firewall.GetInversePair(pair)); err != nil {
+			merr = multierror.Append(merr, fmt.Errorf("remove inverse prerouting rule: %w", err))
+		}
+	}
+
+	if err := r.removeLegacyRouteRule(pair); err != nil {
+		merr = multierror.Append(merr, fmt.Errorf("remove legacy routing rule: %w", err))
+	}
+
+	// Set counters are decremented in the sub-methods above before flush. If flush fails,
+	// counters will be off until the next successful removal or refresh cycle.
+	if err := r.conn.Flush(); err != nil {
+		merr = multierror.Append(merr, fmt.Errorf("flush remove nat rules %s: %w", pair.Destination, err))
+	}
+
+	return nberrors.FormatErrorOrNil(merr)
+}
+
+func (r *family) removeNatRule(pair firewall.RouterPair) error {
+	ruleID := pair.GenKey(firewall.PreroutingFormat)
+
+	rule, exists := r.rules[ruleID]
+	if !exists {
+		log.Debugf("prerouting rule %s not found", ruleID)
+		return nil
+	}
+
+	if rule.Handle == 0 {
+		log.Warnf("prerouting rule %s has no handle, removing stale entry", ruleID)
+		if err := r.decrementSetCounter(rule); err != nil {
+			log.Warnf("decrement set counter for stale rule %s: %v", ruleID, err)
+		}
+		delete(r.rules, ruleID)
+		return nil
+	}
+
+	if err := r.conn.DelRule(rule); err != nil {
+		return fmt.Errorf("remove prerouting rule %s -> %s: %w", pair.Source, pair.Destination, err)
+	}
+
+	log.Debugf("removed prerouting rule %s -> %s", pair.Source, pair.Destination)
+
+	delete(r.rules, ruleID)
+
+	if err := r.decrementSetCounter(rule); err != nil {
+		return fmt.Errorf("decrement set counter: %w", err)
+	}
+
+	return nil
+}

client/firewall/nftables/rule_linux.go

@@ -1,21 +1,26 @@
 package nftables
 
 import (
-	"net"
+	"net/netip"
 
 	"github.com/google/nftables"
+
+	"github.com/netbirdio/netbird/client/firewall/manager"
 )
 
-// Rule to handle management of rules
+// Rule wraps an installed filter rule (peer or route). Source set
+// membership is encoded in the rule's expressions; DeleteFilterRule
+// recovers the set name via findSets so the refcounter can drop the
+// right reference. mangleRule is set only for peer rules.
 type Rule struct {
 	nftRule    *nftables.Rule
 	mangleRule *nftables.Rule
-	nftSet     *nftables.Set
-	ruleID     string
-	ip         net.IP
+	// sources is the canonical source list this rule was created for.
+	sources []netip.Prefix
+	id      manager.RuleID
 }
 
-// GetRuleID returns the rule id
-func (r *Rule) ID() string {
-	return r.ruleID
+// ID returns the rule id
+func (r *Rule) ID() manager.RuleID {
+	return r.id
 }

client/firewall/nftables/testhelpers_linux_test.go

@@ -0,0 +1,27 @@
+//go:build integration && !android
+
+package nftables
+
+import (
+	"fmt"
+	"net"
+	"net/netip"
+)
+
+func pfx(ip net.IP) []netip.Prefix {
+	if ip == nil {
+		return []netip.Prefix{netip.PrefixFrom(netip.IPv4Unspecified(), 0)}
+	}
+	if ip.IsUnspecified() {
+		if ip.To4() != nil {
+			return []netip.Prefix{netip.PrefixFrom(netip.IPv4Unspecified(), 0)}
+		}
+		return []netip.Prefix{netip.PrefixFrom(netip.IPv6Unspecified(), 0)}
+	}
+	a, ok := netip.AddrFromSlice(ip)
+	if !ok {
+		panic(fmt.Sprintf("invalid IP length: %d", len(ip)))
+	}
+	a = a.Unmap()
+	return []netip.Prefix{netip.PrefixFrom(a, a.BitLen())}
+}

client/firewall/uspfilter/filter.go

@@ -5,7 +5,6 @@ import (
 	"encoding/binary"
 	"errors"
 	"fmt"
-	"net"
 	"net/netip"
 	"os"
 	"slices"
@@ -72,12 +71,14 @@ const (
 
 var errNatNotSupported = errors.New("nat not supported with userspace firewall")
 
-// RuleSet is a set of rules grouped by a string key
-type RuleSet map[string]PeerRule
+// peerRules is the canonical list-based storage for peer ACL rules.
+// Match order is significant: drop rules come before accept rules so
+// callers should consult the slice in order.
+type peerRules []*PeerRule
 
-type RouteRules []*RouteRule
+type routeRules []*RouteRule
 
-func (r RouteRules) Sort() {
+func (r routeRules) Sort() {
 	slices.SortStableFunc(r, func(a, b *RouteRule) int {
 		// Deny rules come first
 		if a.action == firewall.ActionDrop && b.action != firewall.ActionDrop {
@@ -86,22 +87,44 @@ func (r RouteRules) Sort() {
 		if a.action != firewall.ActionDrop && b.action == firewall.ActionDrop {
 			return 1
 		}
-		return strings.Compare(a.id, b.id)
+		return strings.Compare(string(a.id), string(b.id))
 	})
 }
 
+// peerRuleSpec carries the parameters that define a peer filter rule,
+// threaded together through the build path so the builders take a single
+// argument instead of a long parameter list.
+type peerRuleSpec struct {
+	mgmtID   []byte
+	sources  []netip.Prefix
+	ipLayer  gopacket.LayerType
+	matchAny bool
+	proto    firewall.Protocol
+	sPort    *firewall.Port
+	dPort    *firewall.Port
+	action   firewall.Action
+}
+
 // Manager userspace firewall manager
 type Manager struct {
-	outgoingRules     map[netip.Addr]RuleSet
-	incomingDenyRules map[netip.Addr]RuleSet
-	incomingRules     map[netip.Addr]RuleSet
-	routeRules        RouteRules
-	routeRulesMap     map[nbid.RuleID]*RouteRule
-	decoders          sync.Pool
-	wgIface           common.IFaceMapper
-	nativeFirewall    firewall.Manager
+	decoders sync.Pool
+	wgIface  common.IFaceMapper
+	// nativeFirewall is the kernel firewall (nftables/iptables) used for
+	// the split case where peer ACLs run in userspace here but routing
+	// stays in the kernel: when the userspace firewall is forced yet the
+	// router keeps using the kernel, route NAT/ACLs and DNAT are
+	// delegated to it. It is nil when no native backend is available.
+	nativeFirewall firewall.Manager
+	mutex          sync.RWMutex
 
-	mutex sync.RWMutex
+	incomingDenyRules   peerRules
+	incomingAcceptRules peerRules
+	incomingDenyIndex   peerRuleIndex
+	incomingAcceptIndex peerRuleIndex
+	peerRulesMap        map[nbid.RuleID]*PeerRule
+
+	routeRules    routeRules
+	routeRulesMap map[nbid.RuleID]*RouteRule
 
 	// indicates whether server routes are disabled
 	disableServerRoutes bool
@@ -183,24 +206,6 @@ func (d *decoder) decodePacket(data []byte) error {
 	}
 }
 
-// Create userspace firewall manager constructor
-func Create(iface common.IFaceMapper, disableServerRoutes bool, flowLogger nftypes.FlowLogger, mtu uint16) (*Manager, error) {
-	return create(iface, nil, disableServerRoutes, flowLogger, mtu)
-}
-
-func CreateWithNativeFirewall(iface common.IFaceMapper, nativeFirewall firewall.Manager, disableServerRoutes bool, flowLogger nftypes.FlowLogger, mtu uint16) (*Manager, error) {
-	if nativeFirewall == nil {
-		return nil, errors.New("native firewall is nil")
-	}
-
-	mgr, err := create(iface, nativeFirewall, disableServerRoutes, flowLogger, mtu)
-	if err != nil {
-		return nil, err
-	}
-
-	return mgr, nil
-}
-
 func parseCreateEnv() (bool, bool, bool) {
 	var disableConntrack, enableLocalForwarding, disableMSSClamping bool
 	var err error
@@ -231,7 +236,7 @@ func parseCreateEnv() (bool, bool, bool) {
 	return disableConntrack, enableLocalForwarding, disableMSSClamping
 }
 
-func create(iface common.IFaceMapper, nativeFirewall firewall.Manager, disableServerRoutes bool, flowLogger nftypes.FlowLogger, mtu uint16) (*Manager, error) {
+func Create(iface common.IFaceMapper, nativeFirewall firewall.Manager, disableServerRoutes bool, flowLogger nftypes.FlowLogger, mtu uint16) (*Manager, error) {
 	disableConntrack, enableLocalForwarding, disableMSSClamping := parseCreateEnv()
 
 	m := &Manager{
@@ -254,11 +259,8 @@ func create(iface common.IFaceMapper, nativeFirewall firewall.Manager, disableSe
 				return d
 			},
 		},
-		nativeFirewall:      nativeFirewall,
-		outgoingRules:       make(map[netip.Addr]RuleSet),
-		incomingDenyRules:   make(map[netip.Addr]RuleSet),
-		incomingRules:       make(map[netip.Addr]RuleSet),
 		wgIface:             iface,
+		nativeFirewall:      nativeFirewall,
 		localipmanager:      newLocalIPManager(),
 		disableServerRoutes: disableServerRoutes,
 		stateful:            !disableConntrack,
@@ -266,6 +268,7 @@ func create(iface common.IFaceMapper, nativeFirewall firewall.Manager, disableSe
 		flowLogger:          flowLogger,
 		netstack:            netstack.IsEnabled(),
 		localForwarding:     enableLocalForwarding,
+		peerRulesMap:        make(map[nbid.RuleID]*PeerRule),
 		routeRulesMap:       make(map[nbid.RuleID]*RouteRule),
 		dnatMappings:        make(map[netip.Addr]netip.Addr),
 		portDNATRules:       []portDNATRule{},
@@ -320,7 +323,7 @@ func (m *Manager) blockInvalidRouted(iface common.IFaceMapper) ([]firewall.Rule,
 	}
 
 	var rules []firewall.Rule
-	v4Rule, err := m.addRouteFiltering(
+	v4Rule, err := m.addRouteRule(
 		nil,
 		sources,
 		firewall.Network{Prefix: wgPrefix},
@@ -336,7 +339,7 @@ func (m *Manager) blockInvalidRouted(iface common.IFaceMapper) ([]firewall.Rule,
 
 	if v6Net.IsValid() {
 		log.Debugf("blocking invalid routed traffic for %s", v6Net)
-		v6Rule, err := m.addRouteFiltering(
+		v6Rule, err := m.addRouteRule(
 			nil,
 			sources,
 			firewall.Network{Prefix: v6Net},
@@ -488,64 +491,136 @@ func (m *Manager) RemoveNatRule(pair firewall.RouterPair) error {
 	return nil
 }
 
-// AddPeerFiltering rule to the firewall
-//
-// If comment argument is empty firewall manager should set
-// rule ID as comment for the rule
-func (m *Manager) AddPeerFiltering(
+// addPeerRule installs an input-chain rule that matches packets
+// by source only. Called from AddFilterRule when the caller doesn't
+// specify a destination. Mixed-family inputs are split: each family
+// gets its own rule with a family-correct ipLayer so packet decoding
+// matches what the matcher expects.
+func (m *Manager) addPeerRule(
 	id []byte,
-	ip net.IP,
+	sources []netip.Prefix,
 	proto firewall.Protocol,
 	sPort *firewall.Port,
 	dPort *firewall.Port,
 	action firewall.Action,
-	_ string,
-) ([]firewall.Rule, error) {
-	// TODO: fix in upper layers
-	i, ok := netip.AddrFromSlice(ip)
-	if !ok {
-		return nil, fmt.Errorf("invalid IP: %s", ip)
-	}
-
-	i = i.Unmap()
-	r := PeerRule{
-		id:        uuid.New().String(),
-		mgmtId:    id,
-		ip:        i,
-		ipLayer:   layers.LayerTypeIPv6,
-		matchByIP: true,
-		drop:      action == firewall.ActionDrop,
-	}
-	if i.Is4() {
-		r.ipLayer = layers.LayerTypeIPv4
-	}
-
-	if s := r.ip.String(); s == "0.0.0.0" || s == "::" {
-		r.matchByIP = false
-	}
-
-	r.sPort = sPort
-	r.dPort = dPort
-
-	r.protoLayer = protoToLayer(proto, r.ipLayer)
-
+) (firewall.Rule, error) {
 	m.mutex.Lock()
-	var targetMap map[netip.Addr]RuleSet
-	if r.drop {
-		targetMap = m.incomingDenyRules
-	} else {
-		targetMap = m.incomingRules
+	defer m.mutex.Unlock()
+
+	if sourcesMatchAny(sources) {
+		spec := peerRuleSpec{
+			mgmtID:   id,
+			sources:  sources,
+			ipLayer:  layerTypeAll,
+			matchAny: true,
+			proto:    proto,
+			sPort:    sPort,
+			dPort:    dPort,
+			action:   action,
+		}
+		return m.addOnePeerRule(spec), nil
 	}
 
-	if _, ok := targetMap[r.ip]; !ok {
-		targetMap[r.ip] = make(RuleSet)
+	// Sources are a single family; normalize v4-mapped prefixes to plain
+	// v4 and pick the matching IP layer.
+	normalized := make([]netip.Prefix, len(sources))
+	ipLayer := layers.LayerTypeIPv4
+	for i, p := range sources {
+		normalized[i] = firewall.UnmapPrefix(p)
+		if normalized[i].Addr().Is6() {
+			ipLayer = layers.LayerTypeIPv6
+		}
 	}
-	targetMap[r.ip][r.id] = r
-	m.mutex.Unlock()
-	return []firewall.Rule{&r}, nil
+	spec := peerRuleSpec{
+		mgmtID:   id,
+		sources:  normalized,
+		ipLayer:  ipLayer,
+		matchAny: false,
+		proto:    proto,
+		sPort:    sPort,
+		dPort:    dPort,
+		action:   action,
+	}
+	return m.addOnePeerRule(spec), nil
 }
 
-func (m *Manager) AddRouteFiltering(
+// addOnePeerRule builds and registers a single-family peer rule, or
+// returns the existing rule when one with the same content key is
+// already installed. The caller must hold m.mutex. The content key is
+// the shared GenerateRuleID with an empty destination, so peer
+// rules dedup the same way route rules and the kernel backends do.
+//
+// There is no refcount: a content key is installed once and deleted on
+// the first DeleteFilterRule for that key. The caller must therefore
+// key its own tracking by the returned rule id so add and delete stay
+// balanced per content key; the acl manager does this via
+// peerRulesPairs. The content key is order-independent, so callers
+// passing the same sources in any order dedup to one rule.
+func (m *Manager) addOnePeerRule(spec peerRuleSpec) *PeerRule {
+	ruleID := nbid.GenerateRuleID(spec.sources, firewall.Network{}, spec.proto, spec.sPort, spec.dPort, spec.action)
+	if existing, ok := m.peerRulesMap[ruleID]; ok {
+		return existing
+	}
+
+	rule := m.buildPeerRule(ruleID, spec)
+	m.registerPeerRule(rule)
+	return rule
+}
+
+func (m *Manager) buildPeerRule(ruleID nbid.RuleID, spec peerRuleSpec) *PeerRule {
+	r := &PeerRule{
+		id:       ruleID,
+		mgmtId:   spec.mgmtID,
+		sources:  spec.sources,
+		matchAny: spec.matchAny,
+		action:   spec.action,
+		srcPort:  spec.sPort,
+		dstPort:  spec.dPort,
+	}
+	if !spec.matchAny {
+		r.sourceAddrs = make(map[netip.Addr]struct{}, len(spec.sources))
+		for _, p := range spec.sources {
+			if p.Bits() == p.Addr().BitLen() {
+				r.sourceAddrs[p.Addr()] = struct{}{}
+			}
+		}
+	}
+	r.protoLayer = protoToLayer(spec.proto, spec.ipLayer)
+	return r
+}
+
+// registerPeerRule records a freshly built peer rule in the matching
+// slice, index, and dedup map. The caller must hold m.mutex.
+func (m *Manager) registerPeerRule(r *PeerRule) {
+	if r.action == firewall.ActionDrop {
+		m.incomingDenyRules = append(m.incomingDenyRules, r)
+		m.incomingDenyIndex.add(r)
+	} else {
+		m.incomingAcceptRules = append(m.incomingAcceptRules, r)
+		m.incomingAcceptIndex.add(r)
+	}
+	m.peerRulesMap[r.id] = r
+}
+
+// sourcesMatchAny reports whether the source list matches every source,
+// i.e. contains an explicit /0 prefix. An empty list does not qualify:
+// AddFilterRule rejects it with ErrNoSources, so "match any" is always
+// the deliberate /0 case.
+func sourcesMatchAny(sources []netip.Prefix) bool {
+	for _, p := range sources {
+		if p.Bits() == 0 {
+			return true
+		}
+	}
+	return false
+}
+
+// AddFilterRule is the unified entry point for both peer (input chain)
+// and route (forward chain) filtering rules. The destination
+// distinguishes the two semantics: a zero Network installs an
+// input-side rule that matches by source only; a set Network installs
+// a forward-side rule that also matches the destination.
+func (m *Manager) AddFilterRule(
 	id []byte,
 	sources []netip.Prefix,
 	destination firewall.Network,
@@ -553,13 +628,37 @@ func (m *Manager) AddRouteFiltering(
 	sPort, dPort *firewall.Port,
 	action firewall.Action,
 ) (firewall.Rule, error) {
+	if len(sources) == 0 {
+		return nil, firewall.ErrNoSources
+	}
+
+	if destination.IsZero() {
+		return m.addPeerRule(id, sources, proto, sPort, dPort, action)
+	}
+
+	m.mutex.Lock()
+	defer m.mutex.Unlock()
+	return m.addRouteRule(id, sources, destination, proto, sPort, dPort, action)
+}
+
+// DeleteFilterRule deletes a filtering rule. The rule's underlying type
+// is used to route to the correct internal path.
+func (m *Manager) DeleteFilterRule(rule firewall.Rule) error {
 	m.mutex.Lock()
 	defer m.mutex.Unlock()
 
-	return m.addRouteFiltering(id, sources, destination, proto, sPort, dPort, action)
+	if r, ok := rule.(*PeerRule); ok {
+		return m.deletePeerRuleLocked(r)
+	}
+
+	// Either our *RouteRule or, under native delegation, a native
+	// route-rule object that implements firewall.Rule but isn't one of
+	// our concrete types. The route path forwards the latter to the
+	// native firewall.
+	return m.deleteRouteRule(rule)
 }
 
-func (m *Manager) addRouteFiltering(
+func (m *Manager) addRouteRule(
 	id []byte,
 	sources []netip.Prefix,
 	destination firewall.Network,
@@ -568,18 +667,17 @@ func (m *Manager) addRouteFiltering(
 	action firewall.Action,
 ) (firewall.Rule, error) {
 	if m.nativeRouter.Load() && m.nativeFirewall != nil {
-		return m.nativeFirewall.AddRouteFiltering(id, sources, destination, proto, sPort, dPort, action)
+		return m.nativeFirewall.AddFilterRule(id, sources, destination, proto, sPort, dPort, action)
 	}
 
-	ruleKey := nbid.GenerateRouteRuleKey(sources, destination, proto, sPort, dPort, action)
+	ruleID := nbid.GenerateRuleID(sources, destination, proto, sPort, dPort, action)
 
-	if existingRule, ok := m.routeRulesMap[ruleKey]; ok {
+	if existingRule, ok := m.routeRulesMap[ruleID]; ok {
 		return existingRule, nil
 	}
 
 	rule := RouteRule{
-		// TODO: consolidate these IDs
-		id:         string(ruleKey),
+		id:         ruleID,
 		mgmtId:     id,
 		sources:    sources,
 		dstSet:     destination.Set,
@@ -594,72 +692,57 @@ func (m *Manager) addRouteFiltering(
 
 	m.routeRules = append(m.routeRules, &rule)
 	m.routeRules.Sort()
-	m.routeRulesMap[ruleKey] = &rule
+	m.routeRulesMap[ruleID] = &rule
 
 	return &rule, nil
 }
 
-func (m *Manager) DeleteRouteRule(rule firewall.Rule) error {
-	m.mutex.Lock()
-	defer m.mutex.Unlock()
-
-	return m.deleteRouteRule(rule)
-}
-
 func (m *Manager) deleteRouteRule(rule firewall.Rule) error {
 	if m.nativeRouter.Load() && m.nativeFirewall != nil {
-		return m.nativeFirewall.DeleteRouteRule(rule)
+		return m.nativeFirewall.DeleteFilterRule(rule)
 	}
 
-	ruleKey := nbid.RuleID(rule.ID())
-	if _, ok := m.routeRulesMap[ruleKey]; !ok {
-		return fmt.Errorf("route rule not found: %s", ruleKey)
+	ruleID := rule.ID()
+	trimmed, _, ok := removeRuleByID(m.routeRules, ruleID)
+	if !ok {
+		return fmt.Errorf("route rule not found: %s", ruleID)
 	}
-
-	idx := slices.IndexFunc(m.routeRules, func(r *RouteRule) bool {
-		return r.id == string(ruleKey)
-	})
-	if idx < 0 {
-		return fmt.Errorf("route rule not found in slice: %s", ruleKey)
-	}
-
-	m.routeRules = slices.Delete(m.routeRules, idx, idx+1)
-	delete(m.routeRulesMap, ruleKey)
+	m.routeRules = trimmed
+	delete(m.routeRulesMap, ruleID)
 	return nil
 }
 
-// DeletePeerRule from the firewall by rule definition
-func (m *Manager) DeletePeerRule(rule firewall.Rule) error {
-	m.mutex.Lock()
-	defer m.mutex.Unlock()
+// deletePeerRuleLocked removes a peer rule from the matching slice,
+// index, and dedup map. The caller must hold m.mutex.
+func (m *Manager) deletePeerRuleLocked(r *PeerRule) error {
+	target, index := &m.incomingAcceptRules, &m.incomingAcceptIndex
+	if r.action == firewall.ActionDrop {
+		target, index = &m.incomingDenyRules, &m.incomingDenyIndex
+	}
 
-	r, ok := rule.(*PeerRule)
+	trimmed, stored, ok := removeRuleByID(*target, r.id)
 	if !ok {
-		return fmt.Errorf("delete rule: invalid rule type: %T", rule)
-	}
-
-	var sourceMap map[netip.Addr]RuleSet
-	if r.drop {
-		sourceMap = m.incomingDenyRules
-	} else {
-		sourceMap = m.incomingRules
-	}
-
-	if ruleset, ok := sourceMap[r.ip]; ok {
-		if _, exists := ruleset[r.id]; !exists {
-			return fmt.Errorf("delete rule: no rule with such id: %v", r.id)
-		}
-		delete(ruleset, r.id)
-		if len(ruleset) == 0 {
-			delete(sourceMap, r.ip)
-		}
-	} else {
 		return fmt.Errorf("delete rule: no rule with such id: %v", r.id)
 	}
-
+	*target = trimmed
+	index.remove(stored)
+	delete(m.peerRulesMap, r.id)
 	return nil
 }
 
+// removeRuleByID removes the first rule whose id matches ruleID from
+// rules, preserving order. It returns the trimmed slice, the removed
+// rule, and whether a match was found.
+func removeRuleByID[S ~[]T, T firewall.Rule](rules S, ruleID firewall.RuleID) (S, T, bool) {
+	idx := slices.IndexFunc(rules, func(r T) bool { return r.ID() == ruleID })
+	var removed T
+	if idx < 0 {
+		return rules, removed, false
+	}
+	removed = rules[idx]
+	return slices.Delete(rules, idx, idx+1), removed, true
+}
+
 // SetLegacyManagement doesn't need to be implemented for this manager
 func (m *Manager) SetLegacyManagement(isLegacy bool) error {
 	if m.nativeFirewall == nil {
@@ -674,9 +757,11 @@ func (m *Manager) Flush() error { return nil }
 // resetState clears all firewall rules and closes connection trackers.
 // Must be called with m.mutex held.
 func (m *Manager) resetState() {
-	clear(m.outgoingRules)
-	clear(m.incomingDenyRules)
-	clear(m.incomingRules)
+	m.incomingDenyRules = m.incomingDenyRules[:0]
+	m.incomingAcceptRules = m.incomingAcceptRules[:0]
+	m.incomingDenyIndex.reset()
+	m.incomingAcceptIndex.reset()
+	clear(m.peerRulesMap)
 	clear(m.routeRulesMap)
 	m.routeRules = m.routeRules[:0]
 	m.udpHookOut.Store(nil)
@@ -820,11 +905,11 @@ func (m *Manager) extractIPs(d *decoder) (srcIP, dstIP netip.Addr) {
 	case layers.LayerTypeIPv4:
 		src, _ := netip.AddrFromSlice(d.ip4.SrcIP)
 		dst, _ := netip.AddrFromSlice(d.ip4.DstIP)
-		return src, dst
+		return src.Unmap(), dst.Unmap()
 	case layers.LayerTypeIPv6:
 		src, _ := netip.AddrFromSlice(d.ip6.SrcIP)
 		dst, _ := netip.AddrFromSlice(d.ip6.DstIP)
-		return src, dst
+		return src.Unmap(), dst.Unmap()
 	default:
 		return netip.Addr{}, netip.Addr{}
 	}
@@ -1404,20 +1489,12 @@ func (m *Manager) peerACLsBlock(srcIP netip.Addr, d *decoder, packetData []byte)
 		return nil, false
 	}
 
-	if mgmtId, filter, ok := validateRule(srcIP, packetData, m.incomingDenyRules[srcIP], d); ok {
+	if mgmtId, filter, ok := m.incomingDenyIndex.match(srcIP, d); ok {
 		return mgmtId, filter
 	}
-
-	if mgmtId, filter, ok := validateRule(srcIP, packetData, m.incomingRules[srcIP], d); ok {
+	if mgmtId, filter, ok := m.incomingAcceptIndex.match(srcIP, d); ok {
 		return mgmtId, filter
 	}
-	if mgmtId, filter, ok := validateRule(srcIP, packetData, m.incomingRules[netip.IPv4Unspecified()], d); ok {
-		return mgmtId, filter
-	}
-	if mgmtId, filter, ok := validateRule(srcIP, packetData, m.incomingRules[netip.IPv6Unspecified()], d); ok {
-		return mgmtId, filter
-	}
-
 	return nil, true
 }
 
@@ -1438,39 +1515,6 @@ func portsMatch(rulePort *firewall.Port, packetPort uint16) bool {
 	return false
 }
 
-func validateRule(ip netip.Addr, packetData []byte, rules map[string]PeerRule, d *decoder) ([]byte, bool, bool) {
-	payloadLayer := d.decoded[1]
-
-	for _, rule := range rules {
-		if rule.matchByIP && ip.Compare(rule.ip) != 0 {
-			continue
-		}
-
-		if rule.protoLayer == layerTypeAll {
-			return rule.mgmtId, rule.drop, true
-		}
-
-		if !protoLayerMatches(rule.protoLayer, payloadLayer) {
-			continue
-		}
-
-		switch payloadLayer {
-		case layers.LayerTypeTCP:
-			if portsMatch(rule.sPort, uint16(d.tcp.SrcPort)) && portsMatch(rule.dPort, uint16(d.tcp.DstPort)) {
-				return rule.mgmtId, rule.drop, true
-			}
-		case layers.LayerTypeUDP:
-			if portsMatch(rule.sPort, uint16(d.udp.SrcPort)) && portsMatch(rule.dPort, uint16(d.udp.DstPort)) {
-				return rule.mgmtId, rule.drop, true
-			}
-		case layers.LayerTypeICMPv4, layers.LayerTypeICMPv6:
-			return rule.mgmtId, rule.drop, true
-		}
-	}
-
-	return nil, false, false
-}
-
 // routeACLsPass returns true if the packet is allowed by the route ACLs
 func (m *Manager) routeACLsPass(srcIP, dstIP netip.Addr, protoLayer gopacket.LayerType, srcPort, dstPort uint16) ([]byte, bool) {
 	m.mutex.RLock()

client/firewall/uspfilter/filter_bench_test.go

@@ -94,7 +94,7 @@ func BenchmarkCoreFiltering(b *testing.B) {
 			stateful: false,
 			setupFunc: func(m *Manager) {
 				// Single rule allowing all traffic
-				_, err := m.AddPeerFiltering(nil, net.ParseIP("0.0.0.0"), fw.ProtocolALL, nil, nil, fw.ActionAccept, "")
+				_, err := m.AddFilterRule(nil, pfx(net.ParseIP("0.0.0.0")), fw.Network{}, fw.ProtocolALL, nil, nil, fw.ActionAccept)
 				require.NoError(b, err)
 			},
 			desc: "Baseline: Single 'allow all' rule without connection tracking",
@@ -114,15 +114,13 @@ func BenchmarkCoreFiltering(b *testing.B) {
 				// Add explicit rules matching return traffic pattern
 				for i := 0; i < 1000; i++ { // Simulate realistic ruleset size
 					ip := generateRandomIPs(1)[0]
-					_, err := m.AddPeerFiltering(
+					_, err := m.AddFilterRule(
 						nil,
-						ip,
+						pfx(ip), fw.Network{},
 						fw.ProtocolTCP,
 						&fw.Port{Values: []uint16{uint16(1024 + i)}},
 						&fw.Port{Values: []uint16{80}},
-						fw.ActionAccept,
-						"",
-					)
+						fw.ActionAccept)
 					require.NoError(b, err)
 				}
 			},
@@ -133,15 +131,13 @@ func BenchmarkCoreFiltering(b *testing.B) {
 			stateful: true,
 			setupFunc: func(m *Manager) {
 				// Add some basic rules but rely on state for established connections
-				_, err := m.AddPeerFiltering(
+				_, err := m.AddFilterRule(
 					nil,
-					net.ParseIP("0.0.0.0"),
+					pfx(net.ParseIP("0.0.0.0")), fw.Network{},
 					fw.ProtocolTCP,
 					nil,
 					nil,
-					fw.ActionDrop,
-					"",
-				)
+					fw.ActionDrop)
 				require.NoError(b, err)
 			},
 			desc: "Connection tracking with established connections",
@@ -170,7 +166,7 @@ func BenchmarkCoreFiltering(b *testing.B) {
 				// Create manager and basic setup
 				manager, _ := Create(&IFaceMock{
 					SetFilterFunc: func(device.PacketFilter) error { return nil },
-				}, false, flowLogger, iface.DefaultMTU)
+				}, nil, false, flowLogger, iface.DefaultMTU)
 				defer b.Cleanup(func() {
 					require.NoError(b, manager.Close(nil))
 				})
@@ -210,7 +206,7 @@ func BenchmarkStateScaling(b *testing.B) {
 		b.Run(fmt.Sprintf("conns_%d", count), func(b *testing.B) {
 			manager, _ := Create(&IFaceMock{
 				SetFilterFunc: func(device.PacketFilter) error { return nil },
-			}, false, flowLogger, iface.DefaultMTU)
+			}, nil, false, flowLogger, iface.DefaultMTU)
 			b.Cleanup(func() {
 				require.NoError(b, manager.Close(nil))
 			})
@@ -253,7 +249,7 @@ func BenchmarkEstablishmentOverhead(b *testing.B) {
 		b.Run(sc.name, func(b *testing.B) {
 			manager, _ := Create(&IFaceMock{
 				SetFilterFunc: func(device.PacketFilter) error { return nil },
-			}, false, flowLogger, iface.DefaultMTU)
+			}, nil, false, flowLogger, iface.DefaultMTU)
 			b.Cleanup(func() {
 				require.NoError(b, manager.Close(nil))
 			})
@@ -411,7 +407,7 @@ func BenchmarkRoutedNetworkReturn(b *testing.B) {
 		b.Run(sc.name, func(b *testing.B) {
 			manager, _ := Create(&IFaceMock{
 				SetFilterFunc: func(device.PacketFilter) error { return nil },
-			}, false, flowLogger, iface.DefaultMTU)
+			}, nil, false, flowLogger, iface.DefaultMTU)
 			b.Cleanup(func() {
 				require.NoError(b, manager.Close(nil))
 			})
@@ -538,7 +534,7 @@ func BenchmarkLongLivedConnections(b *testing.B) {
 
 			manager, _ := Create(&IFaceMock{
 				SetFilterFunc: func(device.PacketFilter) error { return nil },
-			}, false, flowLogger, iface.DefaultMTU)
+			}, nil, false, flowLogger, iface.DefaultMTU)
 			defer b.Cleanup(func() {
 				require.NoError(b, manager.Close(nil))
 			})
@@ -546,7 +542,7 @@ func BenchmarkLongLivedConnections(b *testing.B) {
 			// Setup initial state based on scenario
 			if sc.rules {
 				// Single rule to allow all return traffic from port 80
-				_, err := manager.AddPeerFiltering(nil, net.ParseIP("0.0.0.0"), fw.ProtocolTCP, &fw.Port{Values: []uint16{80}}, nil, fw.ActionAccept, "")
+				_, err := manager.AddFilterRule(nil, pfx(net.ParseIP("0.0.0.0")), fw.Network{}, fw.ProtocolTCP, &fw.Port{Values: []uint16{80}}, nil, fw.ActionAccept)
 				require.NoError(b, err)
 			}
 
@@ -621,7 +617,7 @@ func BenchmarkShortLivedConnections(b *testing.B) {
 
 			manager, _ := Create(&IFaceMock{
 				SetFilterFunc: func(device.PacketFilter) error { return nil },
-			}, false, flowLogger, iface.DefaultMTU)
+			}, nil, false, flowLogger, iface.DefaultMTU)
 			defer b.Cleanup(func() {
 				require.NoError(b, manager.Close(nil))
 			})
@@ -629,7 +625,7 @@ func BenchmarkShortLivedConnections(b *testing.B) {
 			// Setup initial state based on scenario
 			if sc.rules {
 				// Single rule to allow all return traffic from port 80
-				_, err := manager.AddPeerFiltering(nil, net.ParseIP("0.0.0.0"), fw.ProtocolTCP, &fw.Port{Values: []uint16{80}}, nil, fw.ActionAccept, "")
+				_, err := manager.AddFilterRule(nil, pfx(net.ParseIP("0.0.0.0")), fw.Network{}, fw.ProtocolTCP, &fw.Port{Values: []uint16{80}}, nil, fw.ActionAccept)
 				require.NoError(b, err)
 			}
 
@@ -732,14 +728,14 @@ func BenchmarkParallelLongLivedConnections(b *testing.B) {
 
 			manager, _ := Create(&IFaceMock{
 				SetFilterFunc: func(device.PacketFilter) error { return nil },
-			}, false, flowLogger, iface.DefaultMTU)
+			}, nil, false, flowLogger, iface.DefaultMTU)
 			defer b.Cleanup(func() {
 				require.NoError(b, manager.Close(nil))
 			})
 
 			// Setup initial state based on scenario
 			if sc.rules {
-				_, err := manager.AddPeerFiltering(nil, net.ParseIP("0.0.0.0"), fw.ProtocolTCP, &fw.Port{Values: []uint16{80}}, nil, fw.ActionAccept, "")
+				_, err := manager.AddFilterRule(nil, pfx(net.ParseIP("0.0.0.0")), fw.Network{}, fw.ProtocolTCP, &fw.Port{Values: []uint16{80}}, nil, fw.ActionAccept)
 				require.NoError(b, err)
 			}
 
@@ -812,13 +808,13 @@ func BenchmarkParallelShortLivedConnections(b *testing.B) {
 
 			manager, _ := Create(&IFaceMock{
 				SetFilterFunc: func(device.PacketFilter) error { return nil },
-			}, false, flowLogger, iface.DefaultMTU)
+			}, nil, false, flowLogger, iface.DefaultMTU)
 			defer b.Cleanup(func() {
 				require.NoError(b, manager.Close(nil))
 			})
 
 			if sc.rules {
-				_, err := manager.AddPeerFiltering(nil, net.ParseIP("0.0.0.0"), fw.ProtocolTCP, &fw.Port{Values: []uint16{80}}, nil, fw.ActionAccept, "")
+				_, err := manager.AddFilterRule(nil, pfx(net.ParseIP("0.0.0.0")), fw.Network{}, fw.ProtocolTCP, &fw.Port{Values: []uint16{80}}, nil, fw.ActionAccept)
 				require.NoError(b, err)
 			}
 
@@ -931,7 +927,7 @@ func BenchmarkRouteACLs(b *testing.B) {
 
 	for _, r := range rules {
 		dst := fw.Network{Prefix: r.dest}
-		_, err := manager.AddRouteFiltering(nil, r.sources, dst, r.proto, nil, r.port, fw.ActionAccept)
+		_, err := manager.AddFilterRule(nil, r.sources, dst, r.proto, nil, r.port, fw.ActionAccept)
 		if err != nil {
 			b.Fatal(err)
 		}
@@ -1016,7 +1012,7 @@ func BenchmarkMSSClamping(b *testing.B) {
 		b.Run(sc.name, func(b *testing.B) {
 			manager, err := Create(&IFaceMock{
 				SetFilterFunc: func(device.PacketFilter) error { return nil },
-			}, false, flowLogger, iface.DefaultMTU)
+			}, nil, false, flowLogger, iface.DefaultMTU)
 			require.NoError(b, err)
 			defer func() {
 				require.NoError(b, manager.Close(nil))
@@ -1081,7 +1077,7 @@ func BenchmarkMSSClampingOverhead(b *testing.B) {
 		b.Run(sc.name, func(b *testing.B) {
 			manager, err := Create(&IFaceMock{
 				SetFilterFunc: func(device.PacketFilter) error { return nil },
-			}, false, flowLogger, iface.DefaultMTU)
+			}, nil, false, flowLogger, iface.DefaultMTU)
 			require.NoError(b, err)
 			defer func() {
 				require.NoError(b, manager.Close(nil))
@@ -1136,7 +1132,7 @@ func BenchmarkMSSClampingMemory(b *testing.B) {
 		b.Run(sc.name, func(b *testing.B) {
 			manager, err := Create(&IFaceMock{
 				SetFilterFunc: func(device.PacketFilter) error { return nil },
-			}, false, flowLogger, iface.DefaultMTU)
+			}, nil, false, flowLogger, iface.DefaultMTU)
 			require.NoError(b, err)
 			defer func() {
 				require.NoError(b, manager.Close(nil))

client/firewall/uspfilter/filter_filter_test.go

@@ -32,7 +32,7 @@ func TestPeerACLFiltering(t *testing.T) {
 		},
 	}
 
-	manager, err := Create(ifaceMock, false, flowLogger, iface.DefaultMTU)
+	manager, err := Create(ifaceMock, nil, false, flowLogger, iface.DefaultMTU)
 	require.NoError(t, err)
 	require.NotNil(t, manager)
 
@@ -496,40 +496,32 @@ func TestPeerACLFiltering(t *testing.T) {
 		t.Run(tc.name, func(t *testing.T) {
 			if tc.ruleAction == fw.ActionDrop {
 				// add general accept rule for the same IP to test drop rule precedence
-				rules, err := manager.AddPeerFiltering(
+				rules, err := manager.AddFilterRule(
 					nil,
-					net.ParseIP(tc.ruleIP),
+					pfx(net.ParseIP(tc.ruleIP)), fw.Network{},
 					fw.ProtocolALL,
 					nil,
 					nil,
-					fw.ActionAccept,
-					"",
-				)
+					fw.ActionAccept)
 				require.NoError(t, err)
-				require.NotEmpty(t, rules)
+				require.NotNil(t, rules)
 				t.Cleanup(func() {
-					for _, rule := range rules {
-						require.NoError(t, manager.DeletePeerRule(rule))
-					}
+					require.NoError(t, manager.DeleteFilterRule(rules))
 				})
 			}
 
-			rules, err := manager.AddPeerFiltering(
+			rules, err := manager.AddFilterRule(
 				nil,
-				net.ParseIP(tc.ruleIP),
+				pfx(net.ParseIP(tc.ruleIP)), fw.Network{},
 				tc.ruleProto,
 				tc.ruleSrcPort,
 				tc.ruleDstPort,
-				tc.ruleAction,
-				"",
-			)
+				tc.ruleAction)
 			require.NoError(t, err)
-			require.NotEmpty(t, rules)
+			require.NotNil(t, rules)
 
 			t.Cleanup(func() {
-				for _, rule := range rules {
-					require.NoError(t, manager.DeletePeerRule(rule))
-				}
+				require.NoError(t, manager.DeleteFilterRule(rules))
 			})
 
 			packet := createTestPacket(t, tc.srcIP, tc.dstIP, tc.proto, tc.srcPort, tc.dstPort)
@@ -557,7 +549,7 @@ func TestPeerACLFilteringIPv6(t *testing.T) {
 		},
 	}
 
-	manager, err := Create(ifaceMock, false, flowLogger, iface.DefaultMTU)
+	manager, err := Create(ifaceMock, nil, false, flowLogger, iface.DefaultMTU)
 	require.NoError(t, err)
 	t.Cleanup(func() { require.NoError(t, manager.Close(nil)) })
 
@@ -672,22 +664,18 @@ func TestPeerACLFilteringIPv6(t *testing.T) {
 	for _, tc := range testCases {
 		t.Run(tc.name, func(t *testing.T) {
 			if tc.ruleAction == fw.ActionDrop {
-				rules, err := manager.AddPeerFiltering(nil, net.ParseIP(tc.ruleIP), fw.ProtocolALL, nil, nil, fw.ActionAccept, "")
+				rules, err := manager.AddFilterRule(nil, pfx(net.ParseIP(tc.ruleIP)), fw.Network{}, fw.ProtocolALL, nil, nil, fw.ActionAccept)
 				require.NoError(t, err)
 				t.Cleanup(func() {
-					for _, rule := range rules {
-						require.NoError(t, manager.DeletePeerRule(rule))
-					}
+					require.NoError(t, manager.DeleteFilterRule(rules))
 				})
 			}
 
-			rules, err := manager.AddPeerFiltering(nil, net.ParseIP(tc.ruleIP), tc.ruleProto, nil, tc.ruleDstPort, tc.ruleAction, "")
+			rules, err := manager.AddFilterRule(nil, pfx(net.ParseIP(tc.ruleIP)), fw.Network{}, tc.ruleProto, nil, tc.ruleDstPort, tc.ruleAction)
 			require.NoError(t, err)
-			require.NotEmpty(t, rules)
+			require.NotNil(t, rules)
 			t.Cleanup(func() {
-				for _, rule := range rules {
-					require.NoError(t, manager.DeletePeerRule(rule))
-				}
+				require.NoError(t, manager.DeleteFilterRule(rules))
 			})
 
 			packet := createTestPacket(t, tc.srcIP, tc.dstIP, tc.proto, tc.srcPort, tc.dstPort)
@@ -800,7 +788,7 @@ func setupRoutedManager(tb testing.TB, network string) *Manager {
 		},
 	}
 
-	manager, err := Create(ifaceMock, false, flowLogger, iface.DefaultMTU)
+	manager, err := Create(ifaceMock, nil, false, flowLogger, iface.DefaultMTU)
 	require.NoError(tb, err)
 	require.NoError(tb, manager.EnableRouting())
 	require.NotNil(tb, manager)
@@ -1405,7 +1393,7 @@ func TestRouteACLFiltering(t *testing.T) {
 		t.Run(tc.name, func(t *testing.T) {
 			if tc.rule.action == fw.ActionDrop {
 				// add general accept rule to test drop rule
-				rule, err := manager.AddRouteFiltering(
+				rule, err := manager.AddFilterRule(
 					nil,
 					[]netip.Prefix{netip.MustParsePrefix("0.0.0.0/0")},
 					fw.Network{Prefix: netip.MustParsePrefix("0.0.0.0/0")},
@@ -1415,13 +1403,13 @@ func TestRouteACLFiltering(t *testing.T) {
 					fw.ActionAccept,
 				)
 				require.NoError(t, err)
-				require.NotNil(t, rule)
+				require.NotEmpty(t, rule)
 				t.Cleanup(func() {
-					require.NoError(t, manager.DeleteRouteRule(rule))
+					require.NoError(t, manager.DeleteFilterRule(rule))
 				})
 			}
 
-			rule, err := manager.AddRouteFiltering(
+			rule, err := manager.AddFilterRule(
 				nil,
 				tc.rule.sources,
 				tc.rule.dest,
@@ -1431,10 +1419,10 @@ func TestRouteACLFiltering(t *testing.T) {
 				tc.rule.action,
 			)
 			require.NoError(t, err)
-			require.NotNil(t, rule)
+			require.NotEmpty(t, rule)
 
 			t.Cleanup(func() {
-				require.NoError(t, manager.DeleteRouteRule(rule))
+				require.NoError(t, manager.DeleteFilterRule(rule))
 			})
 
 			srcIP := netip.MustParseAddr(tc.srcIP)
@@ -1602,9 +1590,9 @@ func TestRouteACLOrder(t *testing.T) {
 
 	for _, tc := range testCases {
 		t.Run(tc.name, func(t *testing.T) {
-			var rules []fw.Rule
+			var addedRules []fw.Rule
 			for _, r := range tc.rules {
-				rule, err := manager.AddRouteFiltering(
+				rule, err := manager.AddFilterRule(
 					nil,
 					r.sources,
 					r.dest,
@@ -1615,12 +1603,12 @@ func TestRouteACLOrder(t *testing.T) {
 				)
 				require.NoError(t, err)
 				require.NotNil(t, rule)
-				rules = append(rules, rule)
+				addedRules = append(addedRules, rule)
 			}
 
 			t.Cleanup(func() {
-				for _, rule := range rules {
-					require.NoError(t, manager.DeleteRouteRule(rule))
+				for _, rule := range addedRules {
+					require.NoError(t, manager.DeleteFilterRule(rule))
 				}
 			})
 
@@ -1646,7 +1634,7 @@ func TestRouteACLSet(t *testing.T) {
 		},
 	}
 
-	manager, err := Create(ifaceMock, false, flowLogger, iface.DefaultMTU)
+	manager, err := Create(ifaceMock, nil, false, flowLogger, iface.DefaultMTU)
 	require.NoError(t, err)
 	t.Cleanup(func() {
 		require.NoError(t, manager.Close(nil))
@@ -1655,7 +1643,7 @@ func TestRouteACLSet(t *testing.T) {
 	set := fw.NewDomainSet(domain.List{"example.org"})
 
 	// Add rule that uses the set (initially empty)
-	rule, err := manager.AddRouteFiltering(
+	rule, err := manager.AddFilterRule(
 		nil,
 		[]netip.Prefix{netip.MustParsePrefix("0.0.0.0/0")},
 		fw.Network{Set: set},
@@ -1689,7 +1677,7 @@ func TestRouteACLFilteringIPv6(t *testing.T) {
 	manager := setupRoutedManager(t, "10.10.0.100/16")
 
 	v6Dst := netip.MustParsePrefix("fd00:dead:beef::/48")
-	_, err := manager.AddRouteFiltering(
+	_, err := manager.AddFilterRule(
 		nil,
 		[]netip.Prefix{netip.MustParsePrefix("fd00::/16")},
 		fw.Network{Prefix: v6Dst},
@@ -1700,7 +1688,7 @@ func TestRouteACLFilteringIPv6(t *testing.T) {
 	)
 	require.NoError(t, err)
 
-	_, err = manager.AddRouteFiltering(
+	_, err = manager.AddFilterRule(
 		nil,
 		[]netip.Prefix{netip.MustParsePrefix("fd00::/16")},
 		fw.Network{Prefix: netip.MustParsePrefix("fd00:dead:beef:1::/64")},

client/firewall/uspfilter/filter_routeacl_test.go

@@ -29,7 +29,7 @@ func TestAddRouteFilteringReturnsExistingRule(t *testing.T) {
 	destination := fw.Network{Prefix: netip.MustParsePrefix("192.168.1.0/24")}
 
 	// Add rule first time
-	rule1, err := manager.AddRouteFiltering(
+	rule1, err := manager.AddFilterRule(
 		[]byte("policy-1"),
 		sources,
 		destination,
@@ -42,7 +42,7 @@ func TestAddRouteFilteringReturnsExistingRule(t *testing.T) {
 	require.NotNil(t, rule1)
 
 	// Add the same rule again
-	rule2, err := manager.AddRouteFiltering(
+	rule2, err := manager.AddFilterRule(
 		[]byte("policy-1"),
 		sources,
 		destination,
@@ -74,7 +74,7 @@ func TestAddRouteFilteringDifferentRulesGetDifferentIDs(t *testing.T) {
 	sources := []netip.Prefix{netip.MustParsePrefix("100.64.1.0/24")}
 
 	// Add first rule
-	rule1, err := manager.AddRouteFiltering(
+	rule1, err := manager.AddFilterRule(
 		[]byte("policy-1"),
 		sources,
 		fw.Network{Prefix: netip.MustParsePrefix("192.168.1.0/24")},
@@ -86,7 +86,7 @@ func TestAddRouteFilteringDifferentRulesGetDifferentIDs(t *testing.T) {
 	require.NoError(t, err)
 
 	// Add different rule (different destination)
-	rule2, err := manager.AddRouteFiltering(
+	rule2, err := manager.AddFilterRule(
 		[]byte("policy-2"),
 		sources,
 		fw.Network{Prefix: netip.MustParsePrefix("192.168.2.0/24")}, // Different!
@@ -115,7 +115,7 @@ func TestRouteRuleUpdateDoesNotCauseGap(t *testing.T) {
 	sources := []netip.Prefix{netip.MustParsePrefix("100.64.1.0/24")}
 	destination := fw.Network{Prefix: netip.MustParsePrefix("192.168.1.0/24")}
 
-	rule1, err := manager.AddRouteFiltering(
+	rule1, err := manager.AddFilterRule(
 		[]byte("policy-1"),
 		sources,
 		destination,
@@ -132,7 +132,7 @@ func TestRouteRuleUpdateDoesNotCauseGap(t *testing.T) {
 	require.True(t, pass, "Traffic should pass with rule in place")
 
 	// Re-add same rule (simulates network map update)
-	rule2, err := manager.AddRouteFiltering(
+	rule2, err := manager.AddFilterRule(
 		[]byte("policy-1"),
 		sources,
 		destination,
@@ -147,7 +147,7 @@ func TestRouteRuleUpdateDoesNotCauseGap(t *testing.T) {
 	// won't delete rule1 during cleanup. If IDs differed, deleting rule1
 	// would remove the only matching rule and cause a traffic gap.
 	if rule1.ID() != rule2.ID() {
-		err = manager.DeleteRouteRule(rule1)
+		err = manager.DeleteFilterRule(rule1)
 		require.NoError(t, err)
 	}
 
@@ -156,6 +156,59 @@ func TestRouteRuleUpdateDoesNotCauseGap(t *testing.T) {
 		"Traffic should still pass after rule update - no gap should occur")
 }
 
+// TestBlockInvalidRoutedDualStack verifies that when the interface has an
+// IPv6 overlay address, blockInvalidRouted installs a block rule for both
+// the v4 and v6 WG prefixes and that routed traffic to the v6 prefix is
+// denied. The v4-only soft-skip path is covered by
+// TestBlockInvalidRoutedIdempotent, whose mock leaves IPv6Net invalid.
+func TestBlockInvalidRoutedDualStack(t *testing.T) {
+	ctrl := gomock.NewController(t)
+	dev := mocks.NewMockDevice(ctrl)
+	dev.EXPECT().MTU().Return(1500, nil).AnyTimes()
+
+	wgNet := netip.MustParsePrefix("100.64.0.1/16")
+	wgNet6 := netip.MustParsePrefix("fd00:1234::1/64")
+
+	ifaceMock := &IFaceMock{
+		SetFilterFunc: func(device.PacketFilter) error { return nil },
+		AddressFunc: func() wgaddr.Address {
+			return wgaddr.Address{
+				IP:      wgNet.Addr(),
+				Network: wgNet,
+				IPv6:    wgNet6.Addr(),
+				IPv6Net: wgNet6,
+			}
+		},
+		GetDeviceFunc: func() *device.FilteredDevice {
+			return &device.FilteredDevice{Device: dev}
+		},
+		GetWGDeviceFunc: func() *wgdevice.Device {
+			return &wgdevice.Device{}
+		},
+	}
+
+	manager, err := Create(ifaceMock, nil, false, flowLogger, iface.DefaultMTU)
+	require.NoError(t, err)
+	t.Cleanup(func() {
+		require.NoError(t, manager.Close(nil))
+	})
+
+	rules, err := manager.blockInvalidRouted(ifaceMock)
+	require.NoError(t, err)
+	require.Len(t, rules, 2, "dual-stack interface must produce a v4 and a v6 block rule")
+
+	manager.mutex.RLock()
+	ruleCount := len(manager.routeRules)
+	manager.mutex.RUnlock()
+	assert.Equal(t, 2, ruleCount, "should have one block rule per family")
+
+	// v6 routed traffic to the WG prefix must be denied.
+	srcIP := netip.MustParseAddr("2001:db8::1")
+	dstIP := netip.MustParseAddr("fd00:1234::50")
+	_, pass := manager.routeACLsPass(srcIP, dstIP, layers.LayerTypeTCP, 12345, 80)
+	assert.False(t, pass, "block rule should deny routed traffic to the v6 WG prefix")
+}
+
 // TestBlockInvalidRoutedIdempotent verifies that blockInvalidRouted creates
 // exactly one drop rule for the WireGuard network prefix, and calling it again
 // returns the same rule without duplicating.
@@ -182,7 +235,7 @@ func TestBlockInvalidRoutedIdempotent(t *testing.T) {
 		},
 	}
 
-	manager, err := Create(ifaceMock, false, flowLogger, iface.DefaultMTU)
+	manager, err := Create(ifaceMock, nil, false, flowLogger, iface.DefaultMTU)
 	require.NoError(t, err)
 	t.Cleanup(func() {
 		require.NoError(t, manager.Close(nil))
@@ -245,7 +298,7 @@ func TestBlockRuleNotAccumulatedOnRepeatedEnableRouting(t *testing.T) {
 		},
 	}
 
-	manager, err := Create(ifaceMock, false, flowLogger, iface.DefaultMTU)
+	manager, err := Create(ifaceMock, nil, false, flowLogger, iface.DefaultMTU)
 	require.NoError(t, err)
 	t.Cleanup(func() {
 		require.NoError(t, manager.Close(nil))
@@ -274,7 +327,7 @@ func TestRouteRuleCountStableAcrossUpdates(t *testing.T) {
 
 	// Simulate 5 network map updates with the same route rule
 	for i := 0; i < 5; i++ {
-		rule, err := manager.AddRouteFiltering(
+		rule, err := manager.AddFilterRule(
 			[]byte("policy-1"),
 			sources,
 			destination,
@@ -304,7 +357,7 @@ func TestDeleteRouteRuleAfterIdempotentAdd(t *testing.T) {
 	destination := fw.Network{Prefix: netip.MustParsePrefix("192.168.1.0/24")}
 
 	// Add same rule twice
-	rule1, err := manager.AddRouteFiltering(
+	rule1, err := manager.AddFilterRule(
 		[]byte("policy-1"),
 		sources,
 		destination,
@@ -315,7 +368,7 @@ func TestDeleteRouteRuleAfterIdempotentAdd(t *testing.T) {
 	)
 	require.NoError(t, err)
 
-	rule2, err := manager.AddRouteFiltering(
+	rule2, err := manager.AddFilterRule(
 		[]byte("policy-1"),
 		sources,
 		destination,
@@ -329,7 +382,7 @@ func TestDeleteRouteRuleAfterIdempotentAdd(t *testing.T) {
 	require.Equal(t, rule1.ID(), rule2.ID(), "Should return same rule ID")
 
 	// Delete using first reference
-	err = manager.DeleteRouteRule(rule1)
+	err = manager.DeleteFilterRule(rule1)
 	require.NoError(t, err)
 
 	// Verify traffic no longer passes
@@ -364,7 +417,7 @@ func setupTestManager(t *testing.T) *Manager {
 		},
 	}
 
-	manager, err := Create(ifaceMock, false, flowLogger, iface.DefaultMTU)
+	manager, err := Create(ifaceMock, nil, false, flowLogger, iface.DefaultMTU)
 	require.NoError(t, err)
 	require.NoError(t, manager.EnableRouting())
 

client/firewall/uspfilter/filter_test.go

@@ -78,7 +78,7 @@ func TestManagerCreate(t *testing.T) {
 		SetFilterFunc: func(device.PacketFilter) error { return nil },
 	}
 
-	m, err := Create(ifaceMock, false, flowLogger, nbiface.DefaultMTU)
+	m, err := Create(ifaceMock, nil, false, flowLogger, nbiface.DefaultMTU)
 	if err != nil {
 		t.Errorf("failed to create Manager: %v", err)
 		return
@@ -89,7 +89,7 @@ func TestManagerCreate(t *testing.T) {
 	}
 }
 
-func TestManagerAddPeerFiltering(t *testing.T) {
+func TestManagerAddFilterRule(t *testing.T) {
 	isSetFilterCalled := false
 	ifaceMock := &IFaceMock{
 		SetFilterFunc: func(device.PacketFilter) error {
@@ -98,7 +98,7 @@ func TestManagerAddPeerFiltering(t *testing.T) {
 		},
 	}
 
-	m, err := Create(ifaceMock, false, flowLogger, nbiface.DefaultMTU)
+	m, err := Create(ifaceMock, nil, false, flowLogger, nbiface.DefaultMTU)
 	if err != nil {
 		t.Errorf("failed to create Manager: %v", err)
 		return
@@ -109,7 +109,7 @@ func TestManagerAddPeerFiltering(t *testing.T) {
 	port := &fw.Port{Values: []uint16{80}}
 	action := fw.ActionDrop
 
-	rule, err := m.AddPeerFiltering(nil, ip, proto, nil, port, action, "")
+	rule, err := m.AddFilterRule(nil, pfx(ip), fw.Network{}, proto, nil, port, action)
 	if err != nil {
 		t.Errorf("failed to add filtering: %v", err)
 		return
@@ -131,7 +131,7 @@ func TestManagerDeleteRule(t *testing.T) {
 		SetFilterFunc: func(device.PacketFilter) error { return nil },
 	}
 
-	m, err := Create(ifaceMock, false, flowLogger, nbiface.DefaultMTU)
+	m, err := Create(ifaceMock, nil, false, flowLogger, nbiface.DefaultMTU)
 	if err != nil {
 		t.Errorf("failed to create Manager: %v", err)
 		return
@@ -142,63 +142,33 @@ func TestManagerDeleteRule(t *testing.T) {
 	port := &fw.Port{Values: []uint16{80}}
 	action := fw.ActionDrop
 
-	rule2, err := m.AddPeerFiltering(nil, ip.AsSlice(), proto, nil, port, action, "")
+	rule2, err := m.AddFilterRule(nil, pfx(ip.AsSlice()), fw.Network{}, proto, nil, port, action)
 	if err != nil {
 		t.Errorf("failed to add filtering: %v", err)
 		return
 	}
 
-	// Check rules exist in appropriate maps
-	for _, r := range rule2 {
-		peerRule, ok := r.(*PeerRule)
-		if !ok {
-			t.Errorf("rule should be a PeerRule")
-			continue
-		}
-		// Check if rule exists in deny or allow maps based on action
-		var found bool
-		if peerRule.drop {
-			_, found = m.incomingDenyRules[ip][r.ID()]
-		} else {
-			_, found = m.incomingRules[ip][r.ID()]
-		}
-		if !found {
-			t.Errorf("rule2 is not in the expected rules map")
+	peerRule, ok := rule2.(*PeerRule)
+	require.True(t, ok, "rule should be a PeerRule")
+
+	inMap := func() bool {
+		if peerRule.action == fw.ActionDrop {
+			return findRuleByID(m.incomingDenyRules, ip, rule2.ID())
 		}
+		return findRuleByID(m.incomingAcceptRules, ip, rule2.ID())
 	}
 
-	for _, r := range rule2 {
-		err = m.DeletePeerRule(r)
-		if err != nil {
-			t.Errorf("failed to delete rule: %v", err)
-			return
-		}
-	}
+	require.True(t, inMap(), "rule2 should be in the expected rules list")
 
-	// Check rules are removed from appropriate maps
-	for _, r := range rule2 {
-		peerRule, ok := r.(*PeerRule)
-		if !ok {
-			t.Errorf("rule should be a PeerRule")
-			continue
-		}
-		// Check if rule is removed from deny or allow maps based on action
-		var found bool
-		if peerRule.drop {
-			_, found = m.incomingDenyRules[ip][r.ID()]
-		} else {
-			_, found = m.incomingRules[ip][r.ID()]
-		}
-		if found {
-			t.Errorf("rule2 should be removed from the rules map")
-		}
-	}
+	require.NoError(t, m.DeleteFilterRule(rule2), "failed to delete rule")
+
+	require.False(t, inMap(), "rule2 should be removed from the rules list")
 }
 
 func TestSetUDPPacketHook(t *testing.T) {
 	manager, err := Create(&IFaceMock{
 		SetFilterFunc: func(device.PacketFilter) error { return nil },
-	}, false, flowLogger, nbiface.DefaultMTU)
+	}, nil, false, flowLogger, nbiface.DefaultMTU)
 	require.NoError(t, err)
 	t.Cleanup(func() { require.NoError(t, manager.Close(nil)) })
 
@@ -222,7 +192,7 @@ func TestSetUDPPacketHook(t *testing.T) {
 func TestSetTCPPacketHook(t *testing.T) {
 	manager, err := Create(&IFaceMock{
 		SetFilterFunc: func(device.PacketFilter) error { return nil },
-	}, false, flowLogger, nbiface.DefaultMTU)
+	}, nil, false, flowLogger, nbiface.DefaultMTU)
 	require.NoError(t, err)
 	t.Cleanup(func() { require.NoError(t, manager.Close(nil)) })
 
@@ -250,7 +220,7 @@ func TestPeerRuleLifecycleDenyRules(t *testing.T) {
 		SetFilterFunc: func(device.PacketFilter) error { return nil },
 	}
 
-	m, err := Create(ifaceMock, false, flowLogger, nbiface.DefaultMTU)
+	m, err := Create(ifaceMock, nil, false, flowLogger, nbiface.DefaultMTU)
 	require.NoError(t, err)
 	defer func() {
 		require.NoError(t, m.Close(nil))
@@ -260,36 +230,34 @@ func TestPeerRuleLifecycleDenyRules(t *testing.T) {
 	addr := netip.MustParseAddr("192.168.1.1")
 
 	// Add multiple deny rules for different ports
-	rule1, err := m.AddPeerFiltering(nil, ip, fw.ProtocolTCP, nil,
-		&fw.Port{Values: []uint16{22}}, fw.ActionDrop, "")
+	rule1, err := m.AddFilterRule(nil, pfx(ip), fw.Network{}, fw.ProtocolTCP, nil, &fw.Port{Values: []uint16{22}}, fw.ActionDrop)
 	require.NoError(t, err)
 
-	rule2, err := m.AddPeerFiltering(nil, ip, fw.ProtocolTCP, nil,
-		&fw.Port{Values: []uint16{80}}, fw.ActionDrop, "")
+	rule2, err := m.AddFilterRule(nil, pfx(ip), fw.Network{}, fw.ProtocolTCP, nil, &fw.Port{Values: []uint16{80}}, fw.ActionDrop)
 	require.NoError(t, err)
 
 	m.mutex.RLock()
-	denyCount := len(m.incomingDenyRules[addr])
+	denyCount := countRulesForAddr(m.incomingDenyRules, addr)
 	m.mutex.RUnlock()
 	require.Equal(t, 2, denyCount, "Should have exactly 2 deny rules")
 
 	// Delete the first deny rule
-	err = m.DeletePeerRule(rule1[0])
+	err = m.DeleteFilterRule(rule1)
 	require.NoError(t, err)
 
 	m.mutex.RLock()
-	denyCount = len(m.incomingDenyRules[addr])
+	denyCount = countRulesForAddr(m.incomingDenyRules, addr)
 	m.mutex.RUnlock()
 	require.Equal(t, 1, denyCount, "Should have 1 deny rule after deleting first")
 
 	// Delete the second deny rule
-	err = m.DeletePeerRule(rule2[0])
+	err = m.DeleteFilterRule(rule2)
 	require.NoError(t, err)
 
 	m.mutex.RLock()
-	_, exists := m.incomingDenyRules[addr]
+	exists := countRulesForAddr(m.incomingDenyRules, addr) > 0
 	m.mutex.RUnlock()
-	require.False(t, exists, "Deny rules IP entry should be cleaned up when empty")
+	require.False(t, exists, "Deny rules should be cleaned up when empty")
 }
 
 // TestPeerRuleAddAndDeleteDontLeak verifies that repeatedly adding and deleting
@@ -299,7 +267,7 @@ func TestPeerRuleAddAndDeleteDontLeak(t *testing.T) {
 		SetFilterFunc: func(device.PacketFilter) error { return nil },
 	}
 
-	m, err := Create(ifaceMock, false, flowLogger, nbiface.DefaultMTU)
+	m, err := Create(ifaceMock, nil, false, flowLogger, nbiface.DefaultMTU)
 	require.NoError(t, err)
 	defer func() {
 		require.NoError(t, m.Close(nil))
@@ -311,27 +279,21 @@ func TestPeerRuleAddAndDeleteDontLeak(t *testing.T) {
 	// Simulate 10 network map updates: add rule, delete old, add new
 	for i := 0; i < 10; i++ {
 		// Add a deny rule
-		rules, err := m.AddPeerFiltering(nil, ip, fw.ProtocolTCP, nil,
-			&fw.Port{Values: []uint16{22}}, fw.ActionDrop, "")
+		rules, err := m.AddFilterRule(nil, pfx(ip), fw.Network{}, fw.ProtocolTCP, nil, &fw.Port{Values: []uint16{22}}, fw.ActionDrop)
 		require.NoError(t, err)
 
 		// Add an allow rule
-		allowRules, err := m.AddPeerFiltering(nil, ip, fw.ProtocolTCP, nil,
-			&fw.Port{Values: []uint16{80}}, fw.ActionAccept, "")
+		allowRules, err := m.AddFilterRule(nil, pfx(ip), fw.Network{}, fw.ProtocolTCP, nil, &fw.Port{Values: []uint16{80}}, fw.ActionAccept)
 		require.NoError(t, err)
 
 		// Delete them (simulating ACL manager cleanup)
-		for _, r := range rules {
-			require.NoError(t, m.DeletePeerRule(r))
-		}
-		for _, r := range allowRules {
-			require.NoError(t, m.DeletePeerRule(r))
-		}
+		require.NoError(t, m.DeleteFilterRule(rules))
+		require.NoError(t, m.DeleteFilterRule(allowRules))
 	}
 
 	m.mutex.RLock()
-	denyCount := len(m.incomingDenyRules[addr])
-	allowCount := len(m.incomingRules[addr])
+	denyCount := countRulesForAddr(m.incomingDenyRules, addr)
+	allowCount := countRulesForAddr(m.incomingAcceptRules, addr)
 	m.mutex.RUnlock()
 
 	require.Equal(t, 0, denyCount, "No deny rules should remain after cleanup")
@@ -345,7 +307,7 @@ func TestMixedAllowDenyRulesSameIP(t *testing.T) {
 		SetFilterFunc: func(device.PacketFilter) error { return nil },
 	}
 
-	m, err := Create(ifaceMock, false, flowLogger, nbiface.DefaultMTU)
+	m, err := Create(ifaceMock, nil, false, flowLogger, nbiface.DefaultMTU)
 	require.NoError(t, err)
 	defer func() {
 		require.NoError(t, m.Close(nil))
@@ -354,41 +316,39 @@ func TestMixedAllowDenyRulesSameIP(t *testing.T) {
 	ip := net.ParseIP("192.168.1.1")
 
 	// Add allow rule for port 80
-	allowRule, err := m.AddPeerFiltering(nil, ip, fw.ProtocolTCP, nil,
-		&fw.Port{Values: []uint16{80}}, fw.ActionAccept, "")
+	allowRule, err := m.AddFilterRule(nil, pfx(ip), fw.Network{}, fw.ProtocolTCP, nil, &fw.Port{Values: []uint16{80}}, fw.ActionAccept)
 	require.NoError(t, err)
 
 	// Add deny rule for port 22
-	denyRule, err := m.AddPeerFiltering(nil, ip, fw.ProtocolTCP, nil,
-		&fw.Port{Values: []uint16{22}}, fw.ActionDrop, "")
+	denyRule, err := m.AddFilterRule(nil, pfx(ip), fw.Network{}, fw.ProtocolTCP, nil, &fw.Port{Values: []uint16{22}}, fw.ActionDrop)
 	require.NoError(t, err)
 
 	addr := netip.MustParseAddr("192.168.1.1")
 	m.mutex.RLock()
-	allowCount := len(m.incomingRules[addr])
-	denyCount := len(m.incomingDenyRules[addr])
+	allowCount := countRulesForAddr(m.incomingAcceptRules, addr)
+	denyCount := countRulesForAddr(m.incomingDenyRules, addr)
 	m.mutex.RUnlock()
 
 	require.Equal(t, 1, allowCount, "Should have 1 allow rule")
 	require.Equal(t, 1, denyCount, "Should have 1 deny rule")
 
 	// Delete allow rule should not affect deny rule
-	err = m.DeletePeerRule(allowRule[0])
+	err = m.DeleteFilterRule(allowRule)
 	require.NoError(t, err)
 
 	m.mutex.RLock()
-	denyCountAfter := len(m.incomingDenyRules[addr])
+	denyCountAfter := countRulesForAddr(m.incomingDenyRules, addr)
 	m.mutex.RUnlock()
 
 	require.Equal(t, 1, denyCountAfter, "Deny rule should still exist after deleting allow rule")
 
 	// Delete deny rule
-	err = m.DeletePeerRule(denyRule[0])
+	err = m.DeleteFilterRule(denyRule)
 	require.NoError(t, err)
 
 	m.mutex.RLock()
-	_, denyExists := m.incomingDenyRules[addr]
-	_, allowExists := m.incomingRules[addr]
+	denyExists := countRulesForAddr(m.incomingDenyRules, addr) > 0
+	allowExists := countRulesForAddr(m.incomingAcceptRules, addr) > 0
 	m.mutex.RUnlock()
 
 	require.False(t, denyExists, "Deny rules should be empty")
@@ -400,7 +360,7 @@ func TestManagerReset(t *testing.T) {
 		SetFilterFunc: func(device.PacketFilter) error { return nil },
 	}
 
-	m, err := Create(ifaceMock, false, flowLogger, nbiface.DefaultMTU)
+	m, err := Create(ifaceMock, nil, false, flowLogger, nbiface.DefaultMTU)
 	if err != nil {
 		t.Errorf("failed to create Manager: %v", err)
 		return
@@ -411,7 +371,7 @@ func TestManagerReset(t *testing.T) {
 	port := &fw.Port{Values: []uint16{80}}
 	action := fw.ActionDrop
 
-	_, err = m.AddPeerFiltering(nil, ip, proto, nil, port, action, "")
+	_, err = m.AddFilterRule(nil, pfx(ip), fw.Network{}, proto, nil, port, action)
 	if err != nil {
 		t.Errorf("failed to add filtering: %v", err)
 		return
@@ -423,7 +383,7 @@ func TestManagerReset(t *testing.T) {
 		return
 	}
 
-	if len(m.outgoingRules) != 0 || len(m.incomingRules) != 0 || len(m.incomingDenyRules) != 0 {
+	if len(m.incomingAcceptRules) != 0 || len(m.incomingDenyRules) != 0 {
 		t.Errorf("rules are not empty")
 	}
 }
@@ -439,7 +399,7 @@ func TestNotMatchByIP(t *testing.T) {
 		},
 	}
 
-	m, err := Create(ifaceMock, false, flowLogger, nbiface.DefaultMTU)
+	m, err := Create(ifaceMock, nil, false, flowLogger, nbiface.DefaultMTU)
 	if err != nil {
 		t.Errorf("failed to create Manager: %v", err)
 		return
@@ -449,7 +409,7 @@ func TestNotMatchByIP(t *testing.T) {
 	proto := fw.ProtocolUDP
 	action := fw.ActionAccept
 
-	_, err = m.AddPeerFiltering(nil, ip, proto, nil, nil, action, "")
+	_, err = m.AddFilterRule(nil, pfx(ip), fw.Network{}, proto, nil, nil, action)
 	if err != nil {
 		t.Errorf("failed to add filtering: %v", err)
 		return
@@ -502,7 +462,7 @@ func TestRemovePacketHook(t *testing.T) {
 	}
 
 	// creating manager instance
-	manager, err := Create(iface, false, flowLogger, nbiface.DefaultMTU)
+	manager, err := Create(iface, nil, false, flowLogger, nbiface.DefaultMTU)
 	if err != nil {
 		t.Fatalf("Failed to create Manager: %s", err)
 	}
@@ -521,7 +481,7 @@ func TestRemovePacketHook(t *testing.T) {
 func TestProcessOutgoingHooks(t *testing.T) {
 	manager, err := Create(&IFaceMock{
 		SetFilterFunc: func(device.PacketFilter) error { return nil },
-	}, false, flowLogger, nbiface.DefaultMTU)
+	}, nil, false, flowLogger, nbiface.DefaultMTU)
 	require.NoError(t, err)
 
 	manager.udpTracker.Close()
@@ -606,7 +566,7 @@ func TestUSPFilterCreatePerformance(t *testing.T) {
 			ifaceMock := &IFaceMock{
 				SetFilterFunc: func(device.PacketFilter) error { return nil },
 			}
-			manager, err := Create(ifaceMock, false, flowLogger, nbiface.DefaultMTU)
+			manager, err := Create(ifaceMock, nil, false, flowLogger, nbiface.DefaultMTU)
 			require.NoError(t, err)
 			time.Sleep(time.Second)
 
@@ -621,7 +581,7 @@ func TestUSPFilterCreatePerformance(t *testing.T) {
 			start := time.Now()
 			for i := 0; i < testMax; i++ {
 				port := &fw.Port{Values: []uint16{uint16(1000 + i)}}
-				_, err = manager.AddPeerFiltering(nil, ip, "tcp", nil, port, fw.ActionAccept, "")
+				_, err = manager.AddFilterRule(nil, pfx(ip), fw.Network{}, "tcp", nil, port, fw.ActionAccept)
 
 				require.NoError(t, err, "failed to add rule")
 			}
@@ -633,7 +593,7 @@ func TestUSPFilterCreatePerformance(t *testing.T) {
 func TestStatefulFirewall_UDPTracking(t *testing.T) {
 	manager, err := Create(&IFaceMock{
 		SetFilterFunc: func(device.PacketFilter) error { return nil },
-	}, false, flowLogger, nbiface.DefaultMTU)
+	}, nil, false, flowLogger, nbiface.DefaultMTU)
 	require.NoError(t, err)
 
 	manager.udpTracker.Close() // Close the existing tracker
@@ -845,7 +805,7 @@ func TestUpdateSetMerge(t *testing.T) {
 		SetFilterFunc: func(device.PacketFilter) error { return nil },
 	}
 
-	manager, err := Create(ifaceMock, false, flowLogger, nbiface.DefaultMTU)
+	manager, err := Create(ifaceMock, nil, false, flowLogger, nbiface.DefaultMTU)
 	require.NoError(t, err)
 	t.Cleanup(func() {
 		require.NoError(t, manager.Close(nil))
@@ -858,7 +818,7 @@ func TestUpdateSetMerge(t *testing.T) {
 		netip.MustParsePrefix("192.168.1.0/24"),
 	}
 
-	rule, err := manager.AddRouteFiltering(
+	rule, err := manager.AddFilterRule(
 		nil,
 		[]netip.Prefix{netip.MustParsePrefix("0.0.0.0/0")},
 		fw.Network{Set: set},
@@ -931,7 +891,7 @@ func TestUpdateSetDeduplication(t *testing.T) {
 		SetFilterFunc: func(device.PacketFilter) error { return nil },
 	}
 
-	manager, err := Create(ifaceMock, false, flowLogger, nbiface.DefaultMTU)
+	manager, err := Create(ifaceMock, nil, false, flowLogger, nbiface.DefaultMTU)
 	require.NoError(t, err)
 	t.Cleanup(func() {
 		require.NoError(t, manager.Close(nil))
@@ -939,7 +899,7 @@ func TestUpdateSetDeduplication(t *testing.T) {
 
 	set := fw.NewDomainSet(domain.List{"example.org"})
 
-	rule, err := manager.AddRouteFiltering(
+	rule, err := manager.AddFilterRule(
 		nil,
 		[]netip.Prefix{netip.MustParsePrefix("0.0.0.0/0")},
 		fw.Network{Set: set},
@@ -1051,7 +1011,7 @@ func TestMSSClamping(t *testing.T) {
 		},
 	}
 
-	manager, err := Create(ifaceMock, false, flowLogger, 1280)
+	manager, err := Create(ifaceMock, nil, false, flowLogger, 1280)
 	require.NoError(t, err)
 	defer func() {
 		require.NoError(t, manager.Close(nil))
@@ -1243,7 +1203,7 @@ func TestShouldForward(t *testing.T) {
 		return wgaddr.Address{IP: wgIP, Network: netip.PrefixFrom(wgIP, 24)}
 	}
 
-	manager, err := Create(ifaceMock, false, flowLogger, nbiface.DefaultMTU)
+	manager, err := Create(ifaceMock, nil, false, flowLogger, nbiface.DefaultMTU)
 	require.NoError(t, err)
 	defer func() {
 		require.NoError(t, manager.Close(nil))
@@ -1358,7 +1318,7 @@ func TestShouldForward(t *testing.T) {
 
 	// Re-create manager to pick up the new address with IPv6
 	require.NoError(t, manager.Close(nil))
-	manager, err = Create(ifaceMock, false, flowLogger, nbiface.DefaultMTU)
+	manager, err = Create(ifaceMock, nil, false, flowLogger, nbiface.DefaultMTU)
 	require.NoError(t, err)
 
 	v6Cases := []struct {

client/firewall/uspfilter/nat_bench_test.go

@@ -66,7 +66,7 @@ func BenchmarkDNATTranslation(b *testing.B) {
 		b.Run(sc.name, func(b *testing.B) {
 			manager, err := Create(&IFaceMock{
 				SetFilterFunc: func(device.PacketFilter) error { return nil },
-			}, false, flowLogger, iface.DefaultMTU)
+			}, nil, false, flowLogger, iface.DefaultMTU)
 			require.NoError(b, err)
 			defer func() {
 				require.NoError(b, manager.Close(nil))
@@ -126,7 +126,7 @@ func BenchmarkDNATTranslation(b *testing.B) {
 func BenchmarkDNATConcurrency(b *testing.B) {
 	manager, err := Create(&IFaceMock{
 		SetFilterFunc: func(device.PacketFilter) error { return nil },
-	}, false, flowLogger, iface.DefaultMTU)
+	}, nil, false, flowLogger, iface.DefaultMTU)
 	require.NoError(b, err)
 	defer func() {
 		require.NoError(b, manager.Close(nil))
@@ -198,7 +198,7 @@ func BenchmarkDNATScaling(b *testing.B) {
 		b.Run(fmt.Sprintf("mappings_%d", count), func(b *testing.B) {
 			manager, err := Create(&IFaceMock{
 				SetFilterFunc: func(device.PacketFilter) error { return nil },
-			}, false, flowLogger, iface.DefaultMTU)
+			}, nil, false, flowLogger, iface.DefaultMTU)
 			require.NoError(b, err)
 			defer func() {
 				require.NoError(b, manager.Close(nil))
@@ -310,7 +310,7 @@ func BenchmarkChecksumUpdate(b *testing.B) {
 func BenchmarkDNATMemoryAllocations(b *testing.B) {
 	manager, err := Create(&IFaceMock{
 		SetFilterFunc: func(device.PacketFilter) error { return nil },
-	}, false, flowLogger, iface.DefaultMTU)
+	}, nil, false, flowLogger, iface.DefaultMTU)
 	require.NoError(b, err)
 	defer func() {
 		require.NoError(b, manager.Close(nil))
@@ -483,7 +483,7 @@ func BenchmarkPortDNAT(b *testing.B) {
 		b.Run(sc.name, func(b *testing.B) {
 			manager, err := Create(&IFaceMock{
 				SetFilterFunc: func(device.PacketFilter) error { return nil },
-			}, false, flowLogger, iface.DefaultMTU)
+			}, nil, false, flowLogger, iface.DefaultMTU)
 			require.NoError(b, err)
 			defer func() {
 				require.NoError(b, manager.Close(nil))

client/firewall/uspfilter/nat_stateful_test.go

@@ -15,7 +15,7 @@ import (
 func TestPortDNATBasic(t *testing.T) {
 	manager, err := Create(&IFaceMock{
 		SetFilterFunc: func(device.PacketFilter) error { return nil },
-	}, false, flowLogger, iface.DefaultMTU)
+	}, nil, false, flowLogger, iface.DefaultMTU)
 	require.NoError(t, err)
 	defer func() {
 		require.NoError(t, manager.Close(nil))
@@ -51,7 +51,7 @@ func TestPortDNATBasic(t *testing.T) {
 func TestPortDNATMultipleRules(t *testing.T) {
 	manager, err := Create(&IFaceMock{
 		SetFilterFunc: func(device.PacketFilter) error { return nil },
-	}, false, flowLogger, iface.DefaultMTU)
+	}, nil, false, flowLogger, iface.DefaultMTU)
 	require.NoError(t, err)
 	defer func() {
 		require.NoError(t, manager.Close(nil))

client/firewall/uspfilter/nat_test.go

@@ -17,7 +17,7 @@ import (
 func TestDNATTranslationCorrectness(t *testing.T) {
 	manager, err := Create(&IFaceMock{
 		SetFilterFunc: func(device.PacketFilter) error { return nil },
-	}, false, flowLogger, iface.DefaultMTU)
+	}, nil, false, flowLogger, iface.DefaultMTU)
 	require.NoError(t, err)
 	defer func() {
 		require.NoError(t, manager.Close(nil))
@@ -106,7 +106,7 @@ func parsePacket(t testing.TB, packetData []byte) *decoder {
 func TestDNATMappingManagement(t *testing.T) {
 	manager, err := Create(&IFaceMock{
 		SetFilterFunc: func(device.PacketFilter) error { return nil },
-	}, false, flowLogger, iface.DefaultMTU)
+	}, nil, false, flowLogger, iface.DefaultMTU)
 	require.NoError(t, err)
 	defer func() {
 		require.NoError(t, manager.Close(nil))
@@ -154,7 +154,7 @@ func TestDNATMappingManagement(t *testing.T) {
 func TestInboundPortDNAT(t *testing.T) {
 	manager, err := Create(&IFaceMock{
 		SetFilterFunc: func(device.PacketFilter) error { return nil },
-	}, false, flowLogger, iface.DefaultMTU)
+	}, nil, false, flowLogger, iface.DefaultMTU)
 	require.NoError(t, err)
 	defer func() {
 		require.NoError(t, manager.Close(nil))
@@ -204,7 +204,7 @@ func TestInboundPortDNAT(t *testing.T) {
 func TestInboundPortDNATNegative(t *testing.T) {
 	manager, err := Create(&IFaceMock{
 		SetFilterFunc: func(device.PacketFilter) error { return nil },
-	}, false, flowLogger, iface.DefaultMTU)
+	}, nil, false, flowLogger, iface.DefaultMTU)
 	require.NoError(t, err)
 	defer func() {
 		require.NoError(t, manager.Close(nil))

client/firewall/uspfilter/peer_acl_bench_test.go

@@ -0,0 +1,327 @@
+//go:build uspbench
+
+package uspfilter
+
+import (
+	"fmt"
+	"io"
+	"math/rand"
+	"net"
+	"net/netip"
+	"runtime"
+	"testing"
+
+	"github.com/google/gopacket"
+	"github.com/google/gopacket/layers"
+	log "github.com/sirupsen/logrus"
+	"github.com/stretchr/testify/require"
+
+	fw "github.com/netbirdio/netbird/client/firewall/manager"
+	"github.com/netbirdio/netbird/client/iface"
+	"github.com/netbirdio/netbird/client/iface/device"
+	"github.com/netbirdio/netbird/client/iface/wgaddr"
+)
+
+// BenchmarkPeerACLMatch measures the per-packet cost of the peer ACL
+// matcher (peerACLsBlock) across realistic shapes: M distinct policy
+// rules, each with K source peers in its set.
+//
+// With the reverse-source index, miss cost is independent of M and
+// hit cost grows only with the number of rules touching a single
+// srcIP, not with total rule count.
+func BenchmarkPeerACLMatch(b *testing.B) {
+	shapes := []struct{ M, K int }{
+		{1, 100}, {10, 100}, {50, 100}, {100, 100}, {100, 1000},
+	}
+	families := []struct {
+		name string
+		v6   bool
+	}{{"v4", false}, {"v6", true}}
+
+	for _, fam := range families {
+		for _, s := range shapes {
+			b.Run(fmt.Sprintf("%s/M=%d/K=%d/hit", fam.name, s.M, s.K), func(b *testing.B) {
+				runPeerACLBench(b, s.M, s.K, true, fam.v6)
+			})
+			b.Run(fmt.Sprintf("%s/M=%d/K=%d/miss", fam.name, s.M, s.K), func(b *testing.B) {
+				runPeerACLBench(b, s.M, s.K, false, fam.v6)
+			})
+		}
+	}
+}
+
+func runPeerACLBench(b *testing.B, m, k int, hit, v6 bool) {
+	log.SetOutput(io.Discard) // keep manager logs out of the benchmark output
+
+	// Miss packets are dropped, so they always traverse the full peer
+	// ACL matcher (every bucket) without short-circuiting and without
+	// touching conntrack. Disable conntrack for the miss case so it
+	// measures the matcher, not established-state lookups. The hit case
+	// keeps conntrack on: an accepted packet reaches trackInbound, which
+	// needs the trackers conntrack creates.
+	if !hit {
+		b.Setenv("NB_DISABLE_CONNTRACK", "1")
+	}
+
+	bits := 32
+	genPkt := generatePacket
+	addrs := uniqueAddrs
+	if v6 {
+		bits = 128
+		genPkt = generatePacket6
+		addrs = uniqueAddrs6
+	}
+
+	// dstIP must be a local IP so filterInbound takes the local-traffic
+	// path (handleLocalTraffic → peerACLsBlock) we are measuring; an
+	// address the manager doesn't own would be treated as routed and
+	// short-circuit before the peer matcher.
+	dstIP := addrs(1, 2)[0]
+	mockAddr := wgaddr.Address{IP: dstIP, Network: netip.PrefixFrom(dstIP, bits)}
+	if v6 {
+		// The local-IP manager needs a valid v4 address too; expose the v6
+		// dst as the interface's IPv6 so IsLocalIP recognizes it.
+		mockAddr = wgaddr.Address{
+			IP:      netip.MustParseAddr("100.64.0.1"),
+			Network: netip.MustParsePrefix("100.64.0.0/16"),
+			IPv6:    dstIP,
+			IPv6Net: netip.PrefixFrom(dstIP, bits),
+		}
+	}
+	manager, _ := Create(&IFaceMock{
+		SetFilterFunc: func(device.PacketFilter) error { return nil },
+		AddressFunc:   func() wgaddr.Address { return mockAddr },
+	}, nil, false, flowLogger, iface.DefaultMTU)
+	b.Cleanup(func() { require.NoError(b, manager.Close(nil)) })
+
+	// Generate M policies × K source peers, all distinct.
+	all := addrs(m*k, 1)
+	for i := 0; i < m; i++ {
+		sources := make([]netip.Prefix, k)
+		for j, a := range all[i*k : (i+1)*k] {
+			sources[j] = netip.PrefixFrom(a, bits)
+		}
+		_, err := manager.AddFilterRule(
+			nil, sources, fw.Network{}, fw.ProtocolTCP, nil,
+			&fw.Port{Values: []uint16{uint16(80 + i)}},
+			fw.ActionAccept)
+		require.NoError(b, err)
+	}
+
+	// Hit: cycle through real sources, picking the matching policy's port.
+	// Miss: a source from a disjoint range, port 80 (matches no policy).
+	var pktFn func(i int) []byte
+	if hit {
+		pktFn = func(i int) []byte {
+			policy := i % m
+			src := all[policy*k+(i%k)]
+			return genPkt(b, src.AsSlice(), dstIP.AsSlice(),
+				uint16(1024+i%60000), uint16(80+policy), layers.IPProtocolTCP)
+		}
+	} else {
+		miss := addrs(4096, 99)
+		pktFn = func(i int) []byte {
+			return genPkt(b, miss[i%len(miss)].AsSlice(), dstIP.AsSlice(),
+				uint16(1024+i%60000), 80, layers.IPProtocolTCP)
+		}
+	}
+
+	// Pre-build a pool to avoid allocations dominating the measurement.
+	pool := make([][]byte, 1024)
+	for i := range pool {
+		pool[i] = pktFn(i)
+	}
+
+	// Confirm the matcher is actually exercised: a hit packet must be
+	// allowed and a miss packet dropped. Without this the benchmark
+	// could silently time the routed early-return instead.
+	require.Equal(b, !hit, manager.filterInbound(pool[0], 0),
+		"benchmark must reach the peer ACL matcher")
+
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		manager.filterInbound(pool[i%len(pool)], 0)
+	}
+}
+
+// BenchmarkPeerACLIndexMemory reports the resident memory cost of
+// the source-keyed index across realistic deployment shapes. Two
+// dimensions matter: (M, K), the number of policies × peers-per-policy,
+// and overlap, the fraction of peers shared between policies.
+//
+// The output uses ReportMetric("bytes/rule") so the cost can be
+// compared across shapes directly. Total bytes = bytes/rule * M.
+func BenchmarkPeerACLIndexMemory(b *testing.B) {
+	cases := []struct {
+		name        string
+		M, K        int
+		overlapFrac float64 // 0 = disjoint per-policy sources, 1 = all share the same pool
+	}{
+		{"M=10/K=100/disjoint", 10, 100, 0},
+		{"M=100/K=100/disjoint", 100, 100, 0},
+		{"M=100/K=1000/disjoint", 100, 1000, 0},
+		{"M=100/K=1000/overlap=0.5", 100, 1000, 0.5},
+		{"M=100/K=1000/overlap=1.0", 100, 1000, 1.0},
+		{"M=1000/K=100/overlap=1.0", 1000, 100, 1.0},
+	}
+
+	for _, c := range cases {
+		b.Run(c.name, func(b *testing.B) {
+			b.ReportAllocs()
+			for i := 0; i < b.N; i++ {
+				mgr, _ := Create(&IFaceMock{
+					SetFilterFunc: func(device.PacketFilter) error { return nil },
+				}, nil, false, flowLogger, iface.DefaultMTU)
+
+				populateIndexedRules(b, mgr, c.M, c.K, c.overlapFrac)
+
+				runtime.GC()
+				var ms runtime.MemStats
+				runtime.ReadMemStats(&ms)
+				before := ms.HeapAlloc
+
+				// Drop the manager's external roots so we can isolate
+				// the index cost. We hold the manager itself live; the
+				// index is what we measure on the second pass.
+				mgr.incomingAcceptIndex.reset()
+				mgr.incomingDenyIndex.reset()
+				mgr.incomingAcceptRules = mgr.incomingAcceptRules[:0]
+				mgr.incomingDenyRules = mgr.incomingDenyRules[:0]
+				runtime.GC()
+				runtime.ReadMemStats(&ms)
+				after := ms.HeapAlloc
+
+				delta := int64(before) - int64(after)
+				if delta < 0 {
+					delta = 0
+				}
+				b.ReportMetric(float64(delta)/float64(c.M), "bytes/rule")
+				b.ReportMetric(float64(delta), "bytes/total")
+
+				require.NoError(b, mgr.Close(nil))
+			}
+		})
+	}
+}
+
+func populateIndexedRules(b *testing.B, mgr *Manager, m, k int, overlapFrac float64) {
+	b.Helper()
+	pool := uniqueAddrs(k+m*k, 1) // big enough universe
+	sharedLen := int(float64(k) * overlapFrac)
+	if sharedLen > k {
+		sharedLen = k
+	}
+	shared := pool[:sharedLen]
+	uniquePool := pool[sharedLen:]
+
+	for i := 0; i < m; i++ {
+		sources := make([]netip.Prefix, 0, k)
+		for _, a := range shared {
+			sources = append(sources, netip.PrefixFrom(a, 32))
+		}
+		// each policy gets (k-sharedLen) addresses unique to it from the unique pool
+		unique := uniquePool[i*(k-sharedLen) : (i+1)*(k-sharedLen)]
+		for _, a := range unique {
+			sources = append(sources, netip.PrefixFrom(a, 32))
+		}
+		_, err := mgr.AddFilterRule(
+			nil, sources, fw.Network{}, fw.ProtocolTCP, nil,
+			&fw.Port{Values: []uint16{uint16(80 + i)}},
+			fw.ActionAccept)
+		require.NoError(b, err)
+	}
+}
+
+// uniqueAddrs returns n distinct addrs. Seeds 1, 2 are used for
+// policy sources / dst; seed 99 puts misses in 10/8.
+func uniqueAddrs(n int, seed int64) []netip.Addr {
+	out := make([]netip.Addr, 0, n)
+	seen := make(map[netip.Addr]struct{}, n)
+	r := rand.New(rand.NewSource(seed))
+	miss := seed == 99
+	for len(out) < n {
+		var b [4]byte
+		if miss {
+			b[0] = 10
+			b[1] = byte(r.Intn(256))
+		} else {
+			b[0] = 100
+			b[1] = byte(64 + r.Intn(63))
+		}
+		b[2] = byte(r.Intn(256))
+		b[3] = byte(1 + r.Intn(254))
+		a := netip.AddrFrom4(b)
+		if _, ok := seen[a]; ok {
+			continue
+		}
+		seen[a] = struct{}{}
+		out = append(out, a)
+	}
+	return out
+}
+
+// uniqueAddrs6 mirrors uniqueAddrs for IPv6: sources come from the ULA
+// range fd00::/8, the miss set (seed 99) from 2001:db8::/32 so it is
+// disjoint from any source.
+func uniqueAddrs6(n int, seed int64) []netip.Addr {
+	out := make([]netip.Addr, 0, n)
+	seen := make(map[netip.Addr]struct{}, n)
+	r := rand.New(rand.NewSource(seed))
+	miss := seed == 99
+	for len(out) < n {
+		var b [16]byte
+		if miss {
+			b[0], b[1], b[2], b[3] = 0x20, 0x01, 0x0d, 0xb8
+		} else {
+			b[0] = 0xfd
+		}
+		for x := 8; x < 16; x++ {
+			b[x] = byte(r.Intn(256))
+		}
+		a := netip.AddrFrom16(b)
+		if _, ok := seen[a]; ok {
+			continue
+		}
+		seen[a] = struct{}{}
+		out = append(out, a)
+	}
+	return out
+}
+
+// generatePacket6 builds an IPv6 TCP/UDP packet, mirroring
+// generatePacket for the v4 case.
+func generatePacket6(b *testing.B, srcIP, dstIP net.IP, srcPort, dstPort uint16, protocol layers.IPProtocol) []byte {
+	b.Helper()
+
+	ipv6 := &layers.IPv6{
+		Version:    6,
+		HopLimit:   64,
+		NextHeader: protocol,
+		SrcIP:      srcIP,
+		DstIP:      dstIP,
+	}
+
+	var transportLayer gopacket.SerializableLayer
+	switch protocol {
+	case layers.IPProtocolTCP:
+		tcp := &layers.TCP{
+			SrcPort: layers.TCPPort(srcPort),
+			DstPort: layers.TCPPort(dstPort),
+			SYN:     true,
+		}
+		require.NoError(b, tcp.SetNetworkLayerForChecksum(ipv6))
+		transportLayer = tcp
+	case layers.IPProtocolUDP:
+		udp := &layers.UDP{
+			SrcPort: layers.UDPPort(srcPort),
+			DstPort: layers.UDPPort(dstPort),
+		}
+		require.NoError(b, udp.SetNetworkLayerForChecksum(ipv6))
+		transportLayer = udp
+	}
+
+	buf := gopacket.NewSerializeBuffer()
+	opts := gopacket.SerializeOptions{ComputeChecksums: true, FixLengths: true}
+	require.NoError(b, gopacket.SerializeLayers(buf, opts, ipv6, transportLayer, gopacket.Payload("test")))
+	return buf.Bytes()
+}

client/firewall/uspfilter/peer_acl_dedup_test.go

@@ -0,0 +1,149 @@
+package uspfilter
+
+import (
+	"net"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+
+	fw "github.com/netbirdio/netbird/client/firewall/manager"
+	nbiface "github.com/netbirdio/netbird/client/iface"
+	"github.com/netbirdio/netbird/client/iface/device"
+)
+
+func newTestManager(t *testing.T) *Manager {
+	t.Helper()
+	ifaceMock := &IFaceMock{
+		SetFilterFunc: func(device.PacketFilter) error { return nil },
+	}
+	m, err := Create(ifaceMock, nil, false, flowLogger, nbiface.DefaultMTU)
+	require.NoError(t, err, "create manager")
+	return m
+}
+
+// TestAddPeerFiltering_DeduplicatesIdenticalRules verifies that adding
+// the same peer rule twice does not create two backing rules. The acl
+// manager keys its own cache, but the firewall backend must be
+// idempotent on its own so a double-apply cannot leak rules, matching
+// the route path and the kernel backends.
+func TestAddPeerFiltering_DeduplicatesIdenticalRules(t *testing.T) {
+	m := newTestManager(t)
+
+	ip := net.ParseIP("192.168.1.1")
+	proto := fw.ProtocolTCP
+	port := &fw.Port{Values: []uint16{80}}
+	action := fw.ActionDrop
+
+	first, err := m.AddFilterRule(nil, pfx(ip), fw.Network{}, proto, nil, port, action)
+	require.NoError(t, err, "first add")
+
+	second, err := m.AddFilterRule(nil, pfx(ip), fw.Network{}, proto, nil, port, action)
+	require.NoError(t, err, "second add")
+
+	assert.Equal(t, first.ID(), second.ID(), "duplicate add should return the same rule id")
+	assert.Len(t, m.incomingDenyRules, 1, "duplicate add must not create a second backing rule")
+}
+
+// TestDeletePeerFiltering_NoRefcountSingleDeleteRemoves locks the
+// backend's no-refcount contract: a content key installed twice is
+// still one rule, and the first DeleteFilterRule removes it. The
+// backend does not refcount, so balance is the caller's job (it keys
+// its tracking by the returned id and deletes once per key). If this
+// ever silently grew a refcount, the acl manager's delete accounting
+// would diverge from the kernel.
+func TestDeletePeerFiltering_NoRefcountSingleDeleteRemoves(t *testing.T) {
+	m := newTestManager(t)
+
+	ip := net.ParseIP("192.168.1.1")
+	proto := fw.ProtocolTCP
+	port := &fw.Port{Values: []uint16{80}}
+	action := fw.ActionDrop
+
+	first, err := m.AddFilterRule(nil, pfx(ip), fw.Network{}, proto, nil, port, action)
+	require.NoError(t, err, "first add")
+
+	second, err := m.AddFilterRule(nil, pfx(ip), fw.Network{}, proto, nil, port, action)
+	require.NoError(t, err, "second add")
+	require.Equal(t, first.ID(), second.ID(), "dedup to one rule")
+	require.Len(t, m.incomingDenyRules, 1, "still one backing rule after duplicate add")
+
+	require.NoError(t, m.DeleteFilterRule(first), "delete once")
+	assert.Empty(t, m.incomingDenyRules, "single delete removes the backing rule (no refcount)")
+	assert.NotContains(t, m.peerRulesMap, first.ID(), "dedup map entry cleared")
+}
+
+// TestAddPeerFiltering_DeterministicID verifies the peer rule id is a
+// content hash, not a random UUID: identical inputs produce the same id
+// across independent managers. A random id breaks caller-side dedup.
+func TestAddPeerFiltering_DeterministicID(t *testing.T) {
+	ip := net.ParseIP("10.0.0.5")
+	proto := fw.ProtocolUDP
+	port := &fw.Port{Values: []uint16{53}}
+	action := fw.ActionAccept
+
+	m1 := newTestManager(t)
+	r1, err := m1.AddFilterRule(nil, pfx(ip), fw.Network{}, proto, nil, port, action)
+	require.NoError(t, err)
+
+	m2 := newTestManager(t)
+	r2, err := m2.AddFilterRule(nil, pfx(ip), fw.Network{}, proto, nil, port, action)
+	require.NoError(t, err)
+
+	assert.Equal(t, r1.ID(), r2.ID(), "same inputs must produce the same rule id")
+}
+
+// TestAddPeerFiltering_DistinctRulesNotDeduped verifies that rules
+// differing only by port are kept separate.
+func TestAddPeerFiltering_DistinctRulesNotDeduped(t *testing.T) {
+	m := newTestManager(t)
+
+	ip := net.ParseIP("192.168.1.1")
+	proto := fw.ProtocolTCP
+	action := fw.ActionAccept
+
+	r80, err := m.AddFilterRule(nil, pfx(ip), fw.Network{}, proto, nil, &fw.Port{Values: []uint16{80}}, action)
+	require.NoError(t, err)
+
+	r443, err := m.AddFilterRule(nil, pfx(ip), fw.Network{}, proto, nil, &fw.Port{Values: []uint16{443}}, action)
+	require.NoError(t, err)
+
+	assert.NotEqual(t, r80.ID(), r443.ID(), "different ports must produce different rule ids")
+	assert.Len(t, m.incomingAcceptRules, 2, "distinct rules must both be stored")
+}
+
+// TestAddPeerFiltering_SourceVsDestPortNotDeduped verifies that a rule
+// matching on source port and one matching on destination port for the
+// same selector do not collide: the port lands in a different slot, so
+// the content key must differ.
+func TestAddPeerFiltering_SourceVsDestPortNotDeduped(t *testing.T) {
+	m := newTestManager(t)
+
+	ip := net.ParseIP("192.168.1.1")
+	proto := fw.ProtocolTCP
+	port := &fw.Port{Values: []uint16{80}}
+	action := fw.ActionAccept
+
+	dPortRule, err := m.AddFilterRule(nil, pfx(ip), fw.Network{}, proto, nil, port, action)
+	require.NoError(t, err)
+
+	sPortRule, err := m.AddFilterRule(nil, pfx(ip), fw.Network{}, proto, port, nil, action)
+	require.NoError(t, err)
+
+	assert.NotEqual(t, dPortRule.ID(), sPortRule.ID(), "source-port and dest-port matches must produce different rule ids")
+}
+
+// TestAddFilterRule_EmptySourcesRejected verifies that an empty source
+// list is rejected rather than treated as "match any". "Match any" must
+// be an explicit /0, so a zeroed list can never silently widen a rule to
+// every source.
+func TestAddFilterRule_EmptySourcesRejected(t *testing.T) {
+	m := newTestManager(t)
+
+	proto := fw.ProtocolTCP
+	port := &fw.Port{Values: []uint16{80}}
+
+	_, err := m.AddFilterRule(nil, nil, fw.Network{}, proto, nil, port, fw.ActionAccept)
+	require.ErrorIs(t, err, fw.ErrNoSources, "empty sources must be rejected")
+	assert.Empty(t, m.incomingAcceptRules, "no rule should be stored for empty sources")
+}

client/firewall/uspfilter/peer_acl_ipv6_test.go

@@ -0,0 +1,105 @@
+package uspfilter
+
+import (
+	"net"
+	"net/netip"
+	"testing"
+
+	"github.com/google/gopacket"
+	"github.com/google/gopacket/layers"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+
+	fw "github.com/netbirdio/netbird/client/firewall/manager"
+	nbiface "github.com/netbirdio/netbird/client/iface"
+	"github.com/netbirdio/netbird/client/iface/device"
+	"github.com/netbirdio/netbird/client/iface/wgaddr"
+)
+
+func newV6TestManager(t *testing.T, localV6 string) *Manager {
+	t.Helper()
+	ifaceMock := &IFaceMock{
+		SetFilterFunc: func(device.PacketFilter) error { return nil },
+		AddressFunc: func() wgaddr.Address {
+			return wgaddr.Address{
+				IP:      netip.MustParseAddr("100.10.0.100"),
+				Network: netip.MustParsePrefix("100.10.0.0/16"),
+				IPv6:    netip.MustParseAddr(localV6),
+				IPv6Net: netip.MustParsePrefix("fd00::/64"),
+			}
+		},
+	}
+	m, err := Create(ifaceMock, nil, false, flowLogger, nbiface.DefaultMTU)
+	require.NoError(t, err, "create manager")
+	t.Cleanup(func() { require.NoError(t, m.Close(nil)) })
+	return m
+}
+
+func v6UDPPacket(t *testing.T, src, dst string, dstPort uint16) []byte {
+	t.Helper()
+	ip6 := &layers.IPv6{
+		Version:    6,
+		HopLimit:   64,
+		NextHeader: layers.IPProtocolUDP,
+		SrcIP:      net.ParseIP(src),
+		DstIP:      net.ParseIP(dst),
+	}
+	udp := &layers.UDP{SrcPort: 51334, DstPort: layers.UDPPort(dstPort)}
+	require.NoError(t, udp.SetNetworkLayerForChecksum(ip6))
+
+	buf := gopacket.NewSerializeBuffer()
+	opts := gopacket.SerializeOptions{ComputeChecksums: true, FixLengths: true}
+	require.NoError(t, gopacket.SerializeLayers(buf, opts, ip6, udp, gopacket.Payload("test")))
+	return buf.Bytes()
+}
+
+// TestPeerACL_IPv6HostRule verifies the source index resolves /128 v6
+// rules: a matching v6 source is accepted, a non-matching one is
+// denied by the default. This is the end-to-end proof that the index
+// is not v4-only.
+func TestPeerACL_IPv6HostRule(t *testing.T) {
+	m := newV6TestManager(t, "fd00::100")
+
+	src := net.ParseIP("fd00::1")
+	_, err := m.AddFilterRule(nil, pfx(src), fw.Network{}, fw.ProtocolUDP, nil, &fw.Port{Values: []uint16{53}}, fw.ActionAccept)
+	require.NoError(t, err, "add v6 accept rule")
+
+	require.False(t, m.filterInbound(v6UDPPacket(t, "fd00::1", "fd00::100", 53), 0),
+		"v6 packet from the allowed /128 source must be accepted")
+	require.True(t, m.filterInbound(v6UDPPacket(t, "fd00::2", "fd00::100", 53), 0),
+		"v6 packet from an unlisted source must be denied by default")
+}
+
+// TestPeerACL_IPv6IndexBuckets verifies that v6 sources land in the
+// right index bucket: a /128 in bySource keyed by its address, and
+// coarser prefixes (including ::/0) in the nonHost slice.
+func TestPeerACL_IPv6IndexBuckets(t *testing.T) {
+	m := newV6TestManager(t, "fd00::100")
+	port := &fw.Port{Values: []uint16{53}}
+
+	host := netip.MustParseAddr("fd00::1")
+	_, err := m.AddFilterRule(nil, []netip.Prefix{netip.PrefixFrom(host, 128)}, fw.Network{}, fw.ProtocolUDP, nil, port, fw.ActionAccept)
+	require.NoError(t, err)
+	assert.Contains(t, m.incomingAcceptIndex.bySource, host, "/128 v6 source must be indexed by address")
+
+	_, err = m.AddFilterRule(nil, []netip.Prefix{netip.MustParsePrefix("fd00:dead::/64")}, fw.Network{}, fw.ProtocolUDP, nil, port, fw.ActionAccept)
+	require.NoError(t, err)
+	require.Len(t, m.incomingAcceptIndex.nonHost, 1, "coarser v6 prefix must land in nonHost")
+
+	_, err = m.AddFilterRule(nil, []netip.Prefix{netip.MustParsePrefix("::/0")}, fw.Network{}, fw.ProtocolUDP, nil, port, fw.ActionAccept)
+	require.NoError(t, err)
+	require.Len(t, m.incomingAcceptIndex.nonHost, 2, "::/0 source must also land in nonHost")
+}
+
+// TestPeerACL_IPv4MappedSourceNormalized verifies a v4-mapped v6
+// source prefix is normalized to v4 so a plain v4 packet matches it.
+func TestPeerACL_IPv4MappedSourceNormalized(t *testing.T) {
+	m := newTestManager(t)
+
+	mapped := netip.MustParseAddr("::ffff:192.168.1.1")
+	_, err := m.AddFilterRule(nil, []netip.Prefix{netip.PrefixFrom(mapped, mapped.BitLen())}, fw.Network{}, fw.ProtocolUDP, nil, &fw.Port{Values: []uint16{53}}, fw.ActionAccept)
+	require.NoError(t, err)
+
+	v4 := netip.MustParseAddr("192.168.1.1")
+	assert.Contains(t, m.incomingAcceptIndex.bySource, v4, "v4-mapped v6 source must be indexed as plain v4")
+}

client/firewall/uspfilter/peer_index.go

@@ -0,0 +1,139 @@
+package uspfilter
+
+import (
+	"net/netip"
+	"slices"
+
+	"github.com/google/gopacket"
+	"github.com/google/gopacket/layers"
+
+	firewall "github.com/netbirdio/netbird/client/firewall/manager"
+)
+
+// peerRuleIndex is the source-side dispatcher consulted on the packet
+// hot path. It splits rules into two buckets by the shape of their
+// source list:
+//
+//   - bySource: every source is a host prefix (/32 for v4, /128 for
+//     v6). Keyed by the concrete source address, so a hit guarantees
+//     the source filter passes and the matcher goes straight to
+//     proto/port checks. This is the common case for peer ACLs.
+//   - nonHost: any source list with a prefix coarser than a host,
+//     including a /0 "match any". Walked linearly with a per-rule
+//     Contains() check. Expected small or empty for typical peer ACLs.
+//
+// Maintained incrementally by add/remove, never rebuilt.
+type peerRuleIndex struct {
+	bySource map[netip.Addr][]*PeerRule
+	nonHost  []*PeerRule
+}
+
+func (i *peerRuleIndex) add(r *PeerRule) {
+	if hasNonHostSource(r) {
+		i.nonHost = append(i.nonHost, r)
+		return
+	}
+	if i.bySource == nil {
+		i.bySource = make(map[netip.Addr][]*PeerRule)
+	}
+	for a := range r.sourceAddrs {
+		i.bySource[a] = append(i.bySource[a], r)
+	}
+}
+
+func (i *peerRuleIndex) remove(r *PeerRule) {
+	if hasNonHostSource(r) {
+		i.nonHost = slices.DeleteFunc(i.nonHost, eqRule(r))
+		return
+	}
+	if i.bySource == nil {
+		return
+	}
+	for a := range r.sourceAddrs {
+		entries := slices.DeleteFunc(i.bySource[a], eqRule(r))
+		if len(entries) == 0 {
+			delete(i.bySource, a)
+		} else {
+			i.bySource[a] = entries
+		}
+	}
+}
+
+func (i *peerRuleIndex) reset() {
+	i.bySource = nil
+	i.nonHost = i.nonHost[:0]
+}
+
+// match returns the first rule matching src and the decoded packet.
+// Host rules are found by direct map lookup; nonHost rules need a
+// per-rule source Contains() check, except match-any (/0) rules which
+// apply to every source regardless of family (a v4 /0 also matches v6).
+// Within either bucket the matcher runs the proto/port filter.
+func (i *peerRuleIndex) match(src netip.Addr, d *decoder) ([]byte, bool, bool) {
+	payloadLayer := d.decoded[1]
+
+	for _, rule := range i.bySource[src] {
+		if id, drop, ok := matchProto(rule, d, payloadLayer); ok {
+			return id, drop, true
+		}
+	}
+	for _, rule := range i.nonHost {
+		if !rule.matchAny && !prefixesContain(rule.sources, src) {
+			continue
+		}
+		if id, drop, ok := matchProto(rule, d, payloadLayer); ok {
+			return id, drop, true
+		}
+	}
+	return nil, false, false
+}
+
+func eqRule(target *PeerRule) func(*PeerRule) bool {
+	return func(p *PeerRule) bool { return p == target }
+}
+
+// hasNonHostSource reports whether the rule has any source prefix
+// that is not a single host address. Called only at add/remove time,
+// not on the packet path.
+func hasNonHostSource(r *PeerRule) bool {
+	for _, p := range r.sources {
+		if p.Bits() != p.Addr().BitLen() {
+			return true
+		}
+	}
+	return false
+}
+
+// matchProto applies the proto/port half of a rule against the
+// decoded packet. Source matching is the caller's responsibility.
+func matchProto(rule *PeerRule, d *decoder, payloadLayer gopacket.LayerType) ([]byte, bool, bool) {
+	drop := rule.action == firewall.ActionDrop
+	if rule.protoLayer == layerTypeAll {
+		return rule.mgmtId, drop, true
+	}
+	if !protoLayerMatches(rule.protoLayer, payloadLayer) {
+		return nil, false, false
+	}
+	switch payloadLayer {
+	case layers.LayerTypeTCP:
+		if portsMatch(rule.srcPort, uint16(d.tcp.SrcPort)) && portsMatch(rule.dstPort, uint16(d.tcp.DstPort)) {
+			return rule.mgmtId, drop, true
+		}
+	case layers.LayerTypeUDP:
+		if portsMatch(rule.srcPort, uint16(d.udp.SrcPort)) && portsMatch(rule.dstPort, uint16(d.udp.DstPort)) {
+			return rule.mgmtId, drop, true
+		}
+	case layers.LayerTypeICMPv4, layers.LayerTypeICMPv6:
+		return rule.mgmtId, drop, true
+	}
+	return nil, false, false
+}
+
+func prefixesContain(sources []netip.Prefix, src netip.Addr) bool {
+	for _, p := range sources {
+		if p.Contains(src) {
+			return true
+		}
+	}
+	return false
+}

client/firewall/uspfilter/rule.go

@@ -10,24 +10,49 @@ import (
 
 // PeerRule to handle management of rules
 type PeerRule struct {
-	id         string
-	mgmtId     []byte
-	ip         netip.Addr
-	ipLayer    gopacket.LayerType
-	matchByIP  bool
+	id     firewall.RuleID
+	mgmtId []byte
+	// sources is the canonical list of source prefixes this rule
+	// matches against.
+	sources []netip.Prefix
+	// sourceAddrs is a fast-path membership set for host-prefix
+	// sources (/32 v4, /128 v6). Populated alongside sources;
+	// consulted before falling back to prefix scan.
+	sourceAddrs map[netip.Addr]struct{}
+	// matchAny is true when sources covers everything (0.0.0.0/0,
+	// ::/0). In that case neither sourceAddrs nor sources need to be
+	// consulted.
+	matchAny   bool
 	protoLayer gopacket.LayerType
-	sPort      *firewall.Port
-	dPort      *firewall.Port
-	drop bool
+	srcPort    *firewall.Port
+	dstPort    *firewall.Port
+	action     firewall.Action
+}
+
+// matchesSource reports whether the given source address is covered
+// by this rule's source list.
+func (r *PeerRule) matchesSource(src netip.Addr) bool {
+	if r.matchAny {
+		return true
+	}
+	if _, ok := r.sourceAddrs[src]; ok {
+		return true
+	}
+	for _, p := range r.sources {
+		if p.Contains(src) {
+			return true
+		}
+	}
+	return false
 }
 
 // ID returns the rule id
-func (r *PeerRule) ID() string {
+func (r *PeerRule) ID() firewall.RuleID {
 	return r.id
 }
 
 type RouteRule struct {
-	id           string
+	id           firewall.RuleID
 	mgmtId       []byte
 	sources      []netip.Prefix
 	dstSet       firewall.Set
@@ -39,6 +64,6 @@ type RouteRule struct {
 }
 
 // ID returns the rule id
-func (r *RouteRule) ID() string {
+func (r *RouteRule) ID() firewall.RuleID {
 	return r.id
 }

client/firewall/uspfilter/testhelpers_test.go

@@ -0,0 +1,50 @@
+package uspfilter
+
+import (
+	"net"
+	"net/netip"
+
+	firewall "github.com/netbirdio/netbird/client/firewall/manager"
+)
+
+// countRulesForAddr reports how many rules in the given slice match
+// the supplied source address.
+func countRulesForAddr(rules peerRules, src netip.Addr) int {
+	n := 0
+	for _, r := range rules {
+		if r.matchesSource(src) {
+			n++
+		}
+	}
+	return n
+}
+
+// findRuleByID returns true if the rules slice contains a rule with
+// the given id whose source set covers src.
+func findRuleByID(rules peerRules, src netip.Addr, id firewall.RuleID) bool {
+	for _, r := range rules {
+		if r.id == id && r.matchesSource(src) {
+			return true
+		}
+	}
+	return false
+}
+
+// pfx converts a single net.IP into the []netip.Prefix form
+// AddFilterRule expects. A nil or unspecified address becomes a /0
+// ("match any") prefix in the matching family; any other address
+// becomes its /32 (or /128) host prefix.
+func pfx(ip net.IP) []netip.Prefix {
+	if ip == nil {
+		return []netip.Prefix{netip.PrefixFrom(netip.IPv4Unspecified(), 0)}
+	}
+	if ip.IsUnspecified() {
+		if ip.To4() != nil {
+			return []netip.Prefix{netip.PrefixFrom(netip.IPv4Unspecified(), 0)}
+		}
+		return []netip.Prefix{netip.PrefixFrom(netip.IPv6Unspecified(), 0)}
+	}
+	a, _ := netip.AddrFromSlice(ip)
+	a = a.Unmap()
+	return []netip.Prefix{netip.PrefixFrom(a, a.BitLen())}
+}

client/firewall/uspfilter/tracer.go

@@ -285,6 +285,14 @@ func (m *Manager) TracePacket(packetData []byte, direction fw.RuleDirection) *Pa
 	trace.SourceIP = srcIP
 	trace.DestinationIP = dstIP
 
+	// A fragment or otherwise truncated packet has no transport layer.
+	// The inbound datapath drops these via isValidPacket; the tracer must
+	// guard explicitly since every downstream stage reads d.decoded[1].
+	if len(d.decoded) < 2 {
+		trace.AddResult(StageReceived, "Packet has no transport layer (fragment or unsupported protocol)", false)
+		return trace
+	}
+
 	// Determine protocol and ports
 	switch d.decoded[1] {
 	case layers.LayerTypeTCP:

client/firewall/uspfilter/tracer_test.go

@@ -45,7 +45,7 @@ func TestTracePacket(t *testing.T) {
 			},
 		}
 
-		m, err := Create(ifaceMock, false, flowLogger, iface.DefaultMTU)
+		m, err := Create(ifaceMock, nil, false, flowLogger, iface.DefaultMTU)
 		require.NoError(t, err)
 
 		if !statefulMode {
@@ -97,7 +97,7 @@ func TestTracePacket(t *testing.T) {
 				proto := fw.ProtocolTCP
 				port := &fw.Port{Values: []uint16{80}}
 				action := fw.ActionAccept
-				_, err := m.AddPeerFiltering(nil, ip, proto, nil, port, action, "")
+				_, err := m.AddFilterRule(nil, pfx(ip), fw.Network{}, proto, nil, port, action)
 				require.NoError(t, err)
 			},
 			packetBuilder: func() *PacketBuilder {
@@ -121,7 +121,7 @@ func TestTracePacket(t *testing.T) {
 				proto := fw.ProtocolTCP
 				port := &fw.Port{Values: []uint16{80}}
 				action := fw.ActionDrop
-				_, err := m.AddPeerFiltering(nil, ip, proto, nil, port, action, "")
+				_, err := m.AddFilterRule(nil, pfx(ip), fw.Network{}, proto, nil, port, action)
 				require.NoError(t, err)
 			},
 			packetBuilder: func() *PacketBuilder {
@@ -150,7 +150,7 @@ func TestTracePacket(t *testing.T) {
 				proto := fw.ProtocolTCP
 				port := &fw.Port{Values: []uint16{80}}
 				action := fw.ActionAccept
-				_, err := m.AddPeerFiltering(nil, ip, proto, nil, port, action, "")
+				_, err := m.AddFilterRule(nil, pfx(ip), fw.Network{}, proto, nil, port, action)
 				require.NoError(t, err)
 			},
 			packetBuilder: func() *PacketBuilder {
@@ -178,7 +178,7 @@ func TestTracePacket(t *testing.T) {
 				proto := fw.ProtocolTCP
 				port := &fw.Port{Values: []uint16{80}}
 				action := fw.ActionAccept
-				_, err := m.AddPeerFiltering(nil, ip, proto, nil, port, action, "")
+				_, err := m.AddFilterRule(nil, pfx(ip), fw.Network{}, proto, nil, port, action)
 				require.NoError(t, err)
 			},
 			packetBuilder: func() *PacketBuilder {
@@ -205,7 +205,7 @@ func TestTracePacket(t *testing.T) {
 
 				src := netip.PrefixFrom(netip.AddrFrom4([4]byte{1, 1, 1, 1}), 32)
 				dst := netip.PrefixFrom(netip.AddrFrom4([4]byte{192, 168, 17, 2}), 32)
-				_, err := m.AddRouteFiltering(nil, []netip.Prefix{src}, fw.Network{Prefix: dst}, fw.ProtocolTCP, nil, &fw.Port{Values: []uint16{80}}, fw.ActionAccept)
+				_, err := m.AddFilterRule(nil, []netip.Prefix{src}, fw.Network{Prefix: dst}, fw.ProtocolTCP, nil, &fw.Port{Values: []uint16{80}}, fw.ActionAccept)
 				require.NoError(t, err)
 			},
 			packetBuilder: func() *PacketBuilder {
@@ -231,7 +231,7 @@ func TestTracePacket(t *testing.T) {
 
 				src := netip.PrefixFrom(netip.AddrFrom4([4]byte{1, 1, 1, 1}), 32)
 				dst := netip.PrefixFrom(netip.AddrFrom4([4]byte{192, 168, 17, 2}), 32)
-				_, err := m.AddRouteFiltering(nil, []netip.Prefix{src}, fw.Network{Prefix: dst}, fw.ProtocolTCP, nil, &fw.Port{Values: []uint16{80}}, fw.ActionDrop)
+				_, err := m.AddFilterRule(nil, []netip.Prefix{src}, fw.Network{Prefix: dst}, fw.ProtocolTCP, nil, &fw.Port{Values: []uint16{80}}, fw.ActionDrop)
 				require.NoError(t, err)
 			},
 			packetBuilder: func() *PacketBuilder {
@@ -332,7 +332,7 @@ func TestTracePacket(t *testing.T) {
 				ip := net.ParseIP("1.1.1.1")
 				proto := fw.ProtocolICMP
 				action := fw.ActionAccept
-				_, err := m.AddPeerFiltering(nil, ip, proto, nil, nil, action, "")
+				_, err := m.AddFilterRule(nil, pfx(ip), fw.Network{}, proto, nil, nil, action)
 				require.NoError(t, err)
 			},
 			packetBuilder: func() *PacketBuilder {
@@ -355,7 +355,7 @@ func TestTracePacket(t *testing.T) {
 				ip := net.ParseIP("1.1.1.1")
 				proto := fw.ProtocolICMP
 				action := fw.ActionDrop
-				_, err := m.AddPeerFiltering(nil, ip, proto, nil, nil, action, "")
+				_, err := m.AddFilterRule(nil, pfx(ip), fw.Network{}, proto, nil, nil, action)
 				require.NoError(t, err)
 			},
 			packetBuilder: func() *PacketBuilder {
@@ -379,7 +379,7 @@ func TestTracePacket(t *testing.T) {
 				proto := fw.ProtocolUDP
 				port := &fw.Port{Values: []uint16{53}}
 				action := fw.ActionAccept
-				_, err := m.AddPeerFiltering(nil, ip, proto, nil, port, action, "")
+				_, err := m.AddFilterRule(nil, pfx(ip), fw.Network{}, proto, nil, port, action)
 				require.NoError(t, err)
 			},
 			packetBuilder: func() *PacketBuilder {
@@ -423,7 +423,7 @@ func TestTracePacket(t *testing.T) {
 				proto := fw.ProtocolTCP
 				port := &fw.Port{Values: []uint16{80}}
 				action := fw.ActionDrop
-				_, err := m.AddPeerFiltering(nil, ip, proto, nil, port, action, "")
+				_, err := m.AddFilterRule(nil, pfx(ip), fw.Network{}, proto, nil, port, action)
 				require.NoError(t, err)
 			},
 			packetBuilder: func() *PacketBuilder {

client/internal/acl/dispatch_test.go

@@ -0,0 +1,190 @@
+package acl
+
+import (
+	"net/netip"
+	"sync"
+	"testing"
+
+	"github.com/golang/mock/gomock"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+
+	"github.com/netbirdio/netbird/client/firewall"
+	fwmgr "github.com/netbirdio/netbird/client/firewall/manager"
+	"github.com/netbirdio/netbird/client/iface"
+	"github.com/netbirdio/netbird/client/iface/wgaddr"
+	"github.com/netbirdio/netbird/client/internal/acl/mocks"
+	mgmProto "github.com/netbirdio/netbird/shared/management/proto"
+)
+
+// TestNetworkZeroPrefixIsRoute guards the route-vs-peer dispatch
+// invariant: the backends classify a rule as a peer rule purely by the
+// absence of a destination (neither prefix nor set). A default route
+// (0.0.0.0/0 or ::/0) is a valid prefix and must therefore classify as
+// a route, not collapse into the peer path.
+func TestNetworkZeroPrefixIsRoute(t *testing.T) {
+	for _, p := range []string{"0.0.0.0/0", "::/0", "10.0.0.0/8"} {
+		n := fwmgr.Network{Prefix: netip.MustParsePrefix(p)}
+		assert.True(t, n.IsPrefix(), "%s must report IsPrefix", p)
+		assert.True(t, n.IsPrefix() || n.IsSet(), "%s must classify as a route", p)
+	}
+
+	// A zero-value Network is the only peer-rule shape.
+	var empty fwmgr.Network
+	assert.False(t, empty.IsPrefix(), "zero Network must not be a prefix")
+	assert.False(t, empty.IsSet(), "zero Network must not be a set")
+}
+
+// TestDetermineDestinationAlwaysRoute verifies determineDestination
+// never yields an empty Network for a valid route rule: every branch
+// (static prefix, default route, dynamic with/without domains, with and
+// without a local resolver) produces a destination that classifies as a
+// route. If this regresses, a route rule would be dispatched down the
+// peer path, which matches on source only.
+func TestDetermineDestinationAlwaysRoute(t *testing.T) {
+	v4 := []netip.Prefix{netip.MustParsePrefix("10.0.0.0/24")}
+	v6 := []netip.Prefix{netip.MustParsePrefix("2001:db8::/48")}
+
+	cases := []struct {
+		name     string
+		rule     *mgmProto.RouteFirewallRule
+		resolver bool
+		sources  []netip.Prefix
+	}{
+		{"static prefix", &mgmProto.RouteFirewallRule{Destination: "192.168.0.0/16"}, false, v4},
+		{"static default route", &mgmProto.RouteFirewallRule{Destination: "0.0.0.0/0"}, false, v4},
+		{"dynamic with domains + resolver", &mgmProto.RouteFirewallRule{IsDynamic: true, Domains: []string{"example.com"}}, true, v4},
+		{"dynamic no domains + resolver (v4)", &mgmProto.RouteFirewallRule{IsDynamic: true}, true, v4},
+		{"dynamic no domains + resolver (v6)", &mgmProto.RouteFirewallRule{IsDynamic: true}, true, v6},
+		{"dynamic + no local resolver (v4)", &mgmProto.RouteFirewallRule{IsDynamic: true}, false, v4},
+		{"dynamic + no local resolver (v6)", &mgmProto.RouteFirewallRule{IsDynamic: true}, false, v6},
+	}
+
+	for _, tc := range cases {
+		t.Run(tc.name, func(t *testing.T) {
+			dest, err := determineDestination(tc.rule, tc.resolver, tc.sources)
+			require.NoError(t, err)
+			assert.True(t, dest.IsPrefix() || dest.IsSet(),
+				"destination must classify as a route, got empty Network")
+		})
+	}
+}
+
+// countingFirewall wraps a real firewall.Manager and counts filter-rule
+// add/delete calls so a test can assert how many backing rules the acl
+// manager actually creates and tears down.
+type countingFirewall struct {
+	fwmgr.Manager
+	mu       sync.Mutex
+	addCalls int
+	dels     int
+	ruleIDs  map[fwmgr.RuleID]struct{}
+}
+
+// distinctRules returns the number of distinct backing rules the
+// backend produced. Because the backend dedups identical content,
+// repeated AddFilterRule calls for the same rule resolve to one id.
+func (f *countingFirewall) distinctRules() int {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	return len(f.ruleIDs)
+}
+
+func (f *countingFirewall) AddFilterRule(id []byte, sources []netip.Prefix, destination fwmgr.Network, proto fwmgr.Protocol, sPort, dPort *fwmgr.Port, action fwmgr.Action) (fwmgr.Rule, error) {
+	rule, err := f.Manager.AddFilterRule(id, sources, destination, proto, sPort, dPort, action)
+	if err == nil {
+		f.mu.Lock()
+		f.addCalls++
+		if f.ruleIDs == nil {
+			f.ruleIDs = make(map[fwmgr.RuleID]struct{})
+		}
+		if rule != nil {
+			f.ruleIDs[rule.ID()] = struct{}{}
+		}
+		f.mu.Unlock()
+	}
+	return rule, err
+}
+
+func (f *countingFirewall) DeleteFilterRule(r fwmgr.Rule) error {
+	err := f.Manager.DeleteFilterRule(r)
+	if err == nil {
+		f.mu.Lock()
+		f.dels++
+		delete(f.ruleIDs, r.ID())
+		f.mu.Unlock()
+	}
+	return err
+}
+
+func newCountingACL(t *testing.T) (*DefaultManager, *countingFirewall, func()) {
+	t.Helper()
+	t.Setenv("NB_WG_KERNEL_DISABLED", "true")
+	t.Setenv(firewall.EnvForceUserspaceFirewall, "true")
+
+	ctrl := gomock.NewController(t)
+	ifaceMock := mocks.NewMockIFaceMapper(ctrl)
+	ifaceMock.EXPECT().IsUserspaceBind().Return(true).AnyTimes()
+	ifaceMock.EXPECT().SetFilter(gomock.Any())
+	network := netip.MustParsePrefix("172.0.0.1/32")
+	ifaceMock.EXPECT().Name().Return("lo").AnyTimes()
+	ifaceMock.EXPECT().Address().Return(wgaddr.Address{IP: network.Addr(), Network: network}).AnyTimes()
+	ifaceMock.EXPECT().GetWGDevice().Return(nil).AnyTimes()
+
+	realFW, err := firewall.NewFirewall(ifaceMock, nil, flowLogger, false, iface.DefaultMTU)
+	require.NoError(t, err)
+
+	fw := &countingFirewall{Manager: realFW}
+	cleanup := func() {
+		require.NoError(t, realFW.Close(nil))
+		ctrl.Finish()
+	}
+	return NewDefaultManager(fw), fw, cleanup
+}
+
+// TestDuplicateContentPoliciesShareOneRule verifies the dedup contract
+// the backends rely on: two policies that authorize an identical flow
+// (same selector and sources) collapse to a single backing firewall
+// rule, and that rule survives until BOTH policies are gone. This is
+// why the backend can dedup on add without refcounting on delete: the
+// acl manager's pair key matches the backend's content key, so add and
+// delete stay balanced per content key across full-state reapplies.
+func TestDuplicateContentPoliciesShareOneRule(t *testing.T) {
+	acl, fw, cleanup := newCountingACL(t)
+	defer cleanup()
+
+	ruleA := &mgmProto.FirewallRule{
+		PolicyID:  []byte("policy-A"),
+		PeerIP:    "10.0.0.1",
+		Direction: mgmProto.RuleDirection_IN,
+		Action:    mgmProto.RuleAction_ACCEPT,
+		Protocol:  mgmProto.RuleProtocol_TCP,
+		Port:      "443",
+	}
+	ruleB := &mgmProto.FirewallRule{
+		PolicyID:  []byte("policy-B"),
+		PeerIP:    "10.0.0.1",
+		Direction: mgmProto.RuleDirection_IN,
+		Action:    mgmProto.RuleAction_ACCEPT,
+		Protocol:  mgmProto.RuleProtocol_TCP,
+		Port:      "443",
+	}
+
+	// Both policies present: identical content collapses to one rule.
+	acl.ApplyFiltering(&mgmProto.NetworkMap{FirewallRules: []*mgmProto.FirewallRule{ruleA, ruleB}, FirewallRulesIsEmpty: false}, false)
+	assert.Equal(t, 1, fw.distinctRules(), "identical-content policies must produce one backing rule")
+	assert.Equal(t, 1, len(acl.peerRulesPairs), "one content key, one pair")
+
+	// Drop policy A only: the shared rule is still authorized by B, so
+	// nothing is deleted.
+	acl.ApplyFiltering(&mgmProto.NetworkMap{FirewallRules: []*mgmProto.FirewallRule{ruleB}, FirewallRulesIsEmpty: false}, false)
+	assert.Equal(t, 1, fw.distinctRules(), "no new backing rule on reapply")
+	assert.Equal(t, 0, fw.dels, "rule must survive while any policy still authorizes it")
+	assert.Equal(t, 1, len(acl.peerRulesPairs))
+
+	// Drop policy B too: now the content key has no authorizer and the
+	// single backing rule is removed exactly once.
+	acl.ApplyFiltering(&mgmProto.NetworkMap{FirewallRules: nil, FirewallRulesIsEmpty: true}, false)
+	assert.Equal(t, 1, fw.dels, "rule removed once when last policy is gone")
+	assert.Equal(t, 0, len(acl.peerRulesPairs))
+}

client/internal/acl/grouping_test.go

@@ -0,0 +1,318 @@
+package acl
+
+import (
+	"errors"
+	"net/netip"
+	"testing"
+
+	"github.com/golang/mock/gomock"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+
+	"github.com/netbirdio/netbird/client/firewall"
+	fwmgr "github.com/netbirdio/netbird/client/firewall/manager"
+	"github.com/netbirdio/netbird/client/iface"
+	"github.com/netbirdio/netbird/client/iface/wgaddr"
+	"github.com/netbirdio/netbird/client/internal/acl/mocks"
+	mgmProto "github.com/netbirdio/netbird/shared/management/proto"
+	"github.com/netbirdio/netbird/shared/netiputil"
+)
+
+// TestGroupPeerRulesPolicyIDSeparates verifies that two FirewallRules
+// with identical selectors but different PolicyIDs do NOT get merged
+// into one group, so each policy's sources merge under its own
+// attribution id. (Identical-content groups may still dedup to one
+// backing rule at the backend; see TestDuplicateContentPoliciesShareOneRule.)
+func TestGroupPeerRulesPolicyIDSeparates(t *testing.T) {
+	rules := []*mgmProto.FirewallRule{
+		{
+			PolicyID:  []byte("policy-A"),
+			PeerIP:    "10.0.0.1",
+			Direction: mgmProto.RuleDirection_IN,
+			Action:    mgmProto.RuleAction_ACCEPT,
+			Protocol:  mgmProto.RuleProtocol_TCP,
+			Port:      "443",
+		},
+		{
+			PolicyID:  []byte("policy-B"),
+			PeerIP:    "10.0.0.1",
+			Direction: mgmProto.RuleDirection_IN,
+			Action:    mgmProto.RuleAction_ACCEPT,
+			Protocol:  mgmProto.RuleProtocol_TCP,
+			Port:      "443",
+		},
+	}
+
+	groups, denyErr, err := groupPeerRules(rules)
+	require.NoError(t, denyErr)
+	require.NoError(t, err)
+	require.Len(t, groups, 2, "rules with different PolicyIDs must produce separate groups")
+}
+
+// TestGroupPeerRulesFamilySeparates verifies that v4 and v6 rules
+// belonging to the same policy don't merge.
+func TestGroupPeerRulesFamilySeparates(t *testing.T) {
+	rules := []*mgmProto.FirewallRule{
+		{
+			PolicyID:  []byte("policy-A"),
+			PeerIP:    "10.0.0.1",
+			Direction: mgmProto.RuleDirection_IN,
+			Action:    mgmProto.RuleAction_ACCEPT,
+			Protocol:  mgmProto.RuleProtocol_TCP,
+			Port:      "443",
+		},
+		{
+			PolicyID:  []byte("policy-A"),
+			PeerIP:    "2001:db8::1",
+			Direction: mgmProto.RuleDirection_IN,
+			Action:    mgmProto.RuleAction_ACCEPT,
+			Protocol:  mgmProto.RuleProtocol_TCP,
+			Port:      "443",
+		},
+	}
+
+	groups, denyErr, err := groupPeerRules(rules)
+	require.NoError(t, denyErr)
+	require.NoError(t, err)
+	require.Len(t, groups, 2, "rules of different families must produce separate groups")
+
+	var sawV4, sawV6 bool
+	for _, g := range groups {
+		require.Len(t, g.sources, 1)
+		if g.sources[0].Addr().Is4() {
+			sawV4 = true
+		}
+		if g.sources[0].Addr().Is6() {
+			sawV6 = true
+		}
+	}
+	assert.True(t, sawV4 && sawV6)
+}
+
+// TestGroupPeerRulesSplitsMixedFamilySingleRule verifies that a single
+// FirewallRule carrying both v4 and v6 source prefixes is split into one
+// group per family. Each backend keys a rule to a single family, so a
+// group whose sources span families would mismatch the other family's
+// sources. mgmt normally emits one rule per family; this guards against
+// a mixed-family rule slipping through.
+func TestGroupPeerRulesSplitsMixedFamilySingleRule(t *testing.T) {
+	srcs := [][]byte{
+		netiputil.EncodeAddr(netip.MustParseAddr("10.0.0.1")),
+		netiputil.EncodeAddr(netip.MustParseAddr("2001:db8::1")),
+		netiputil.EncodeAddr(netip.MustParseAddr("10.0.0.2")),
+		netiputil.EncodeAddr(netip.MustParseAddr("2001:db8::2")),
+	}
+	rules := []*mgmProto.FirewallRule{
+		{
+			PolicyID:       []byte("policy-A"),
+			SourcePrefixes: srcs,
+			Direction:      mgmProto.RuleDirection_IN,
+			Action:         mgmProto.RuleAction_ACCEPT,
+			Protocol:       mgmProto.RuleProtocol_TCP,
+			Port:           "443",
+		},
+	}
+
+	groups, denyErr, err := groupPeerRules(rules)
+	require.NoError(t, denyErr)
+	require.NoError(t, err)
+	require.Len(t, groups, 2, "mixed-family sources in one rule must split into two groups")
+
+	for _, g := range groups {
+		require.Len(t, g.sources, 2)
+		v6 := prefixIsV6(g.sources[0])
+		for _, s := range g.sources {
+			assert.Equal(t, v6, prefixIsV6(s), "every source in a group must share one family")
+		}
+	}
+}
+
+// TestGroupPeerRulesMergesSameSelector verifies that rules sharing
+// every distinguishing field (policy, family, direction, action,
+// proto, port) collapse into a single multi-source group.
+func TestGroupPeerRulesMergesSameSelector(t *testing.T) {
+	mk := func(peerIP string) *mgmProto.FirewallRule {
+		return &mgmProto.FirewallRule{
+			PolicyID:  []byte("policy-A"),
+			PeerIP:    peerIP,
+			Direction: mgmProto.RuleDirection_IN,
+			Action:    mgmProto.RuleAction_ACCEPT,
+			Protocol:  mgmProto.RuleProtocol_TCP,
+			Port:      "443",
+		}
+	}
+	rules := []*mgmProto.FirewallRule{mk("10.0.0.1"), mk("10.0.0.2"), mk("10.0.0.3")}
+
+	groups, denyErr, err := groupPeerRules(rules)
+	require.NoError(t, denyErr)
+	require.NoError(t, err)
+	require.Len(t, groups, 1)
+	require.Len(t, groups[0].sources, 3)
+}
+
+// TestGroupPeerRulesPortSeparates verifies that PortInfo is part of the
+// selector key: rules differing only in port must not merge, and a
+// single port must not merge with a range. A regression dropping the
+// port from the key would collapse rules for different ports into one.
+func TestGroupPeerRulesPortSeparates(t *testing.T) {
+	mkPort := func(peerIP string, port uint32) *mgmProto.FirewallRule {
+		return &mgmProto.FirewallRule{
+			PolicyID:  []byte("policy-A"),
+			PeerIP:    peerIP,
+			Direction: mgmProto.RuleDirection_IN,
+			Action:    mgmProto.RuleAction_ACCEPT,
+			Protocol:  mgmProto.RuleProtocol_TCP,
+			PortInfo:  &mgmProto.PortInfo{PortSelection: &mgmProto.PortInfo_Port{Port: port}},
+		}
+	}
+
+	groups, denyErr, err := groupPeerRules([]*mgmProto.FirewallRule{
+		mkPort("10.0.0.1", 80), mkPort("10.0.0.2", 80), mkPort("10.0.0.3", 443),
+	})
+	require.NoError(t, denyErr)
+	require.NoError(t, err)
+	require.Len(t, groups, 2, "rules on different ports must not merge")
+
+	rangeRule := &mgmProto.FirewallRule{
+		PolicyID:  []byte("policy-A"),
+		PeerIP:    "10.0.0.4",
+		Direction: mgmProto.RuleDirection_IN,
+		Action:    mgmProto.RuleAction_ACCEPT,
+		Protocol:  mgmProto.RuleProtocol_TCP,
+		PortInfo:  &mgmProto.PortInfo{PortSelection: &mgmProto.PortInfo_Range_{Range: &mgmProto.PortInfo_Range{Start: 80, End: 90}}},
+	}
+	groups, denyErr, err = groupPeerRules([]*mgmProto.FirewallRule{mkPort("10.0.0.1", 80), rangeRule})
+	require.NoError(t, denyErr)
+	require.NoError(t, err)
+	require.Len(t, groups, 2, "a single port and a range must not merge")
+}
+
+// TestGroupPeerRulesUsesSourcePrefixesWhenPresent verifies that the
+// new sourcePrefixes wire field is consumed and produces a
+// multi-source group in one shot (no client-side merging needed).
+func TestGroupPeerRulesUsesSourcePrefixesWhenPresent(t *testing.T) {
+	srcs := [][]byte{
+		netiputil.EncodeAddr(netip.MustParseAddr("10.0.0.1")),
+		netiputil.EncodeAddr(netip.MustParseAddr("10.0.0.2")),
+		netiputil.EncodeAddr(netip.MustParseAddr("10.0.0.3")),
+	}
+	rules := []*mgmProto.FirewallRule{
+		{
+			PolicyID:       []byte("policy-A"),
+			SourcePrefixes: srcs,
+			Direction:      mgmProto.RuleDirection_IN,
+			Action:         mgmProto.RuleAction_ACCEPT,
+			Protocol:       mgmProto.RuleProtocol_TCP,
+			Port:           "443",
+		},
+	}
+
+	groups, denyErr, err := groupPeerRules(rules)
+	require.NoError(t, denyErr)
+	require.NoError(t, err)
+	require.Len(t, groups, 1)
+	require.Len(t, groups[0].sources, 3)
+}
+
+// TestGroupPeerRulesActionSeparates verifies the obvious: accept
+// and drop rules with the same selector don't merge.
+func TestGroupPeerRulesActionSeparates(t *testing.T) {
+	rules := []*mgmProto.FirewallRule{
+		{
+			PolicyID:  []byte("policy-A"),
+			PeerIP:    "10.0.0.1",
+			Direction: mgmProto.RuleDirection_IN,
+			Action:    mgmProto.RuleAction_ACCEPT,
+			Protocol:  mgmProto.RuleProtocol_TCP,
+			Port:      "443",
+		},
+		{
+			PolicyID:  []byte("policy-A"),
+			PeerIP:    "10.0.0.1",
+			Direction: mgmProto.RuleDirection_IN,
+			Action:    mgmProto.RuleAction_DROP,
+			Protocol:  mgmProto.RuleProtocol_TCP,
+			Port:      "443",
+		},
+	}
+
+	groups, denyErr, err := groupPeerRules(rules)
+	require.NoError(t, denyErr)
+	require.NoError(t, err)
+	require.Len(t, groups, 2)
+}
+
+// failingDeleteFirewall wraps a real firewall.Manager and forces the
+// next N DeleteFilterRule calls to fail. Used to verify that the acl
+// manager retains rules whose deletion was rejected by the backend,
+// so they get retried on the next ApplyFiltering pass instead of
+// becoming orphans.
+type failingDeleteFirewall struct {
+	fwmgr.Manager
+	failCount int
+}
+
+func (f *failingDeleteFirewall) DeleteFilterRule(r fwmgr.Rule) error {
+	if f.failCount > 0 {
+		f.failCount--
+		return errors.New("simulated delete failure")
+	}
+	return f.Manager.DeleteFilterRule(r)
+}
+
+// TestApplyFilteringRetainsRulesOnDeleteFailure verifies that a
+// transient DeleteFilterRule error doesn't make the acl manager
+// forget about a rule. The rule must remain in peerRulesPairs so the
+// next ApplyFiltering pass attempts the delete again.
+func TestApplyFilteringRetainsRulesOnDeleteFailure(t *testing.T) {
+	t.Setenv("NB_WG_KERNEL_DISABLED", "true")
+	t.Setenv(firewall.EnvForceUserspaceFirewall, "true")
+
+	ctrl := gomock.NewController(t)
+	defer ctrl.Finish()
+
+	ifaceMock := mocks.NewMockIFaceMapper(ctrl)
+	ifaceMock.EXPECT().IsUserspaceBind().Return(true).AnyTimes()
+	ifaceMock.EXPECT().SetFilter(gomock.Any())
+	network := netip.MustParsePrefix("172.0.0.1/32")
+	ifaceMock.EXPECT().Name().Return("lo").AnyTimes()
+	ifaceMock.EXPECT().Address().Return(wgaddr.Address{IP: network.Addr(), Network: network}).AnyTimes()
+	ifaceMock.EXPECT().GetWGDevice().Return(nil).AnyTimes()
+
+	realFW, err := firewall.NewFirewall(ifaceMock, nil, flowLogger, false, iface.DefaultMTU)
+	require.NoError(t, err)
+	defer func() { require.NoError(t, realFW.Close(nil)) }()
+
+	fw := &failingDeleteFirewall{Manager: realFW}
+	acl := NewDefaultManager(fw)
+
+	// First pass: install a rule.
+	netmap1 := &mgmProto.NetworkMap{
+		FirewallRules: []*mgmProto.FirewallRule{
+			{
+				PolicyID:  []byte("policy-A"),
+				PeerIP:    "10.0.0.1",
+				Direction: mgmProto.RuleDirection_IN,
+				Action:    mgmProto.RuleAction_DROP,
+				Protocol:  mgmProto.RuleProtocol_TCP,
+				Port:      "22",
+			},
+		},
+		FirewallRulesIsEmpty: false,
+	}
+	acl.ApplyFiltering(netmap1, false)
+	require.Equal(t, 1, len(acl.peerRulesPairs), "rule should be installed")
+
+	// Second pass: remove the rule from the map. The backend will
+	// fail the delete; the acl manager must retain the rule.
+	fw.failCount = 1
+	netmap2 := &mgmProto.NetworkMap{FirewallRules: nil, FirewallRulesIsEmpty: true}
+	acl.ApplyFiltering(netmap2, false)
+	require.Equal(t, 1, len(acl.peerRulesPairs),
+		"rule must be retained when DeleteFilterRule fails so it gets retried")
+
+	// Third pass: same map, backend no longer fails. The rule
+	// should now succeed in being removed.
+	acl.ApplyFiltering(netmap2, false)
+	require.Equal(t, 0, len(acl.peerRulesPairs), "retry should succeed")
+}

client/internal/acl/id/id.go

@@ -5,18 +5,18 @@ import (
 	"encoding/hex"
 	"fmt"
 	"net/netip"
+	"slices"
 	"strconv"
 
 	"github.com/netbirdio/netbird/client/firewall/manager"
 )
 
-type RuleID string
+// RuleID aliases manager.RuleID so existing nbid.RuleID references
+// keep working while the canonical type lives in the firewall package.
+type RuleID = manager.RuleID
 
-func (r RuleID) ID() string {
-	return string(r)
-}
-
-func GenerateRouteRuleKey(
+// GenerateRuleID returns a deterministic content hash identifying a filter rule.
+func GenerateRuleID(
 	sources []netip.Prefix,
 	destination manager.Network,
 	proto manager.Protocol,
@@ -24,6 +24,7 @@ func GenerateRouteRuleKey(
 	dPort *manager.Port,
 	action manager.Action,
 ) RuleID {
+	sources = slices.Clone(sources)
 	manager.SortPrefixes(sources)
 
 	h := sha256.New()

client/internal/acl/manager.go

@@ -1,8 +1,6 @@
 package acl
 
 import (
-	"crypto/md5"
-	"encoding/hex"
 	"errors"
 	"fmt"
 	"net/netip"
@@ -23,6 +21,10 @@ import (
 
 var ErrSourceRangesEmpty = errors.New("sources range is empty")
 
+// ErrNoRuleReturned is returned when the firewall backend reports success
+// from AddFilterRule but yields no rule to track.
+var ErrNoRuleReturned = errors.New("backend returned no rule")
+
 // Manager is a ACL rules manager
 type Manager interface {
 	ApplyFiltering(networkMap *mgmProto.NetworkMap, dnsRouteFeatureFlag bool)
@@ -31,17 +33,46 @@ type Manager interface {
 // DefaultManager uses firewall manager to handle
 type DefaultManager struct {
 	firewall       firewall.Manager
-	ipsetCounter   int
 	peerRulesPairs map[id.RuleID][]firewall.Rule
-	routeRules     map[id.RuleID]struct{}
+	routeRules     map[id.RuleID]firewall.Rule
 	mutex          sync.Mutex
 }
 
+// peerRuleGroup collapses a set of single-source FirewallRules sharing
+// the same selector into one multi-source rule to push to the backend.
+type peerRuleGroup struct {
+	direction mgmProto.RuleDirection
+	action    mgmProto.RuleAction
+	protocol  mgmProto.RuleProtocol
+	port      *mgmProto.PortInfo
+	// legacyPort is used only when PortInfo is empty (old management).
+	legacyPort string
+	policyID   []byte
+	sources    []netip.Prefix
+}
+
+// peerRuleKey is the comparable selector that decides which single-source
+// rules merge into one group. Rules with an equal key collapse into one
+// multi-source backend rule. PortInfo is flattened into its scalar fields
+// so the key compares by value; policyID keeps policies separate so two
+// policies authorizing different peers don't merge under one attribution.
+type peerRuleKey struct {
+	v6         bool
+	policyID   string
+	direction  mgmProto.RuleDirection
+	action     mgmProto.RuleAction
+	protocol   mgmProto.RuleProtocol
+	legacyPort string
+	port       uint16
+	rangeStart uint16
+	rangeEnd   uint16
+}
+
 func NewDefaultManager(fm firewall.Manager) *DefaultManager {
 	return &DefaultManager{
 		firewall:       fm,
 		peerRulesPairs: make(map[id.RuleID][]firewall.Rule),
-		routeRules:     make(map[id.RuleID]struct{}),
+		routeRules:     make(map[id.RuleID]firewall.Rule),
 	}
 }
 
@@ -68,10 +99,12 @@ func (d *DefaultManager) ApplyFiltering(networkMap *mgmProto.NetworkMap, dnsRout
 			time.Since(start), total)
 	}()
 
-	d.applyPeerACLs(networkMap)
+	if err := d.applyPeerACLs(networkMap); err != nil {
+		log.Errorf("apply peer ACLs: %v", err)
+	}
 
 	if err := d.applyRouteACLs(networkMap.RoutesFirewallRules, dnsRouteFeatureFlag); err != nil {
-		log.Errorf("Failed to apply route ACLs: %v", err)
+		log.Errorf("apply route ACLs: %v", err)
 	}
 
 	if err := d.firewall.Flush(); err != nil {
@@ -79,7 +112,7 @@ func (d *DefaultManager) ApplyFiltering(networkMap *mgmProto.NetworkMap, dnsRout
 	}
 }
 
-func (d *DefaultManager) applyPeerACLs(networkMap *mgmProto.NetworkMap) {
+func (d *DefaultManager) applyPeerACLs(networkMap *mgmProto.NetworkMap) error {
 	rules := networkMap.FirewallRules
 
 	// if we got empty rules list but management not set networkMap.FirewallRulesIsEmpty flag
@@ -102,59 +135,158 @@ func (d *DefaultManager) applyPeerACLs(networkMap *mgmProto.NetworkMap) {
 		)
 	}
 
-	newRulePairs := make(map[id.RuleID][]firewall.Rule)
-	ipsetByRuleSelectors := make(map[string]string)
+	// Group incoming single-source rules from management by their
+	// (direction, action, proto, port) selector and merge sources.
+	// One call to the firewall backend per merged rule.
+	// A deny we cannot decode would leave its traffic unblocked, so skip
+	// the whole pass and keep existing rules until the next sync.
+	groups, denyErr, err := groupPeerRules(rules)
+	if denyErr != nil {
+		return fmt.Errorf("decode deny rule sources: %w", denyErr)
+	}
 
-	// TODO: deny rules should be fatal: if a deny rule fails to apply, we must
-	// roll back all allow rules to avoid a fail-open where allowed traffic bypasses
-	// the missing deny. Currently we accumulate errors and continue.
+	newRulePairs := make(map[id.RuleID][]firewall.Rule)
 	var merr *multierror.Error
-	for _, r := range rules {
-		// if this rule is member of rule selection with more than DefaultIPsCountForSet
-		// it's IP address can be used in the ipset for firewall manager which supports it
-		selector := d.getRuleGroupingSelector(r)
-		ipsetName, ok := ipsetByRuleSelectors[selector]
-		if !ok {
-			d.ipsetCounter++
-			ipsetName = fmt.Sprintf("nb%07d", d.ipsetCounter)
-			ipsetByRuleSelectors[selector] = ipsetName
-		}
-		pairID, rulePair, err := d.protoRuleToFirewallRule(r, ipsetName)
-		if err != nil {
-			merr = multierror.Append(merr, fmt.Errorf("apply firewall rule: %w", err))
+	if err != nil {
+		merr = multierror.Append(merr, err)
+	}
+
+	// Apply denies first. A deny that fails to install is a security
+	// failure (fail-open), so if any deny errors we roll back the
+	// denies we already installed in this pass and bail out without
+	// installing any accept. Pre-existing rules stay untouched until
+	// the next successful pass clears them.
+	denies, accepts := splitDenyAccept(groups)
+	if err := d.installPeerGroups(denies, newRulePairs, true); err != nil {
+		return fmt.Errorf("install deny rules: %w", err)
+	}
+
+	if err := d.installPeerGroups(accepts, newRulePairs, false); err != nil {
+		merr = multierror.Append(merr, err)
+	}
+
+	// Tear down rules that disappeared from the networkmap. Any rule
+	// the backend refuses to delete stays in our tracking so it gets
+	// retried on the next ApplyFiltering. Otherwise a transient
+	// delete failure would leak the rule in the firewall until the
+	// process exits.
+	for pairID, rules := range d.peerRulesPairs {
+		if _, ok := newRulePairs[pairID]; ok {
 			continue
 		}
-		if len(rulePair) > 0 {
-			d.peerRulesPairs[pairID] = rulePair
-			newRulePairs[pairID] = rulePair
-		}
-	}
-
-	if merr != nil {
-		log.Errorf("failed to apply %d peer ACL rule(s): %v", merr.Len(), nberrors.FormatErrorOrNil(merr))
-	}
-
-	for pairID, rules := range d.peerRulesPairs {
-		if _, ok := newRulePairs[pairID]; !ok {
-			for _, rule := range rules {
-				if err := d.firewall.DeletePeerRule(rule); err != nil {
-					log.Errorf("failed to delete peer firewall rule: %v", err)
-					continue
-				}
+		var remaining []firewall.Rule
+		for _, rule := range rules {
+			if err := d.firewall.DeleteFilterRule(rule); err != nil {
+				log.Errorf("failed to delete peer firewall rule, will retry: %v", err)
+				remaining = append(remaining, rule)
 			}
-			delete(d.peerRulesPairs, pairID)
+		}
+		if len(remaining) > 0 {
+			newRulePairs[pairID] = remaining
 		}
 	}
 	d.peerRulesPairs = newRulePairs
+
+	return nberrors.FormatErrorOrNil(merr)
+}
+
+// installPeerGroups applies each group and records the resulting rule
+// pairs in newRulePairs. With atomic set (deny rules), a single failure
+// rolls back every rule installed in this call and returns, leaving the
+// firewall exactly as before: denies are fail-closed and must be applied
+// all-or-nothing. With atomic unset (accept rules), failures are
+// accumulated and the remaining groups still install, so one malformed
+// allow cannot drop every other legitimate allow in the pass.
+func (d *DefaultManager) installPeerGroups(groups []*peerRuleGroup, newRulePairs map[id.RuleID][]firewall.Rule, atomic bool) error {
+	var freshlyInstalled []id.RuleID
+	var merr *multierror.Error
+	for _, g := range groups {
+		pairID, rulePair, err := d.applyPeerGroup(g)
+		if err != nil {
+			if atomic {
+				d.rollbackInstalled(freshlyInstalled)
+				return fmt.Errorf("apply firewall rule: %w", err)
+			}
+			merr = multierror.Append(merr, fmt.Errorf("apply firewall rule: %w", err))
+			continue
+		}
+		if len(rulePair) == 0 {
+			continue
+		}
+		if _, existed := d.peerRulesPairs[pairID]; !existed {
+			freshlyInstalled = append(freshlyInstalled, pairID)
+		}
+		d.peerRulesPairs[pairID] = rulePair
+		newRulePairs[pairID] = rulePair
+	}
+	return nberrors.FormatErrorOrNil(merr)
+}
+
+func (d *DefaultManager) rollbackInstalled(pairIDs []id.RuleID) {
+	var merr *multierror.Error
+	for _, pairID := range pairIDs {
+		for _, rule := range d.peerRulesPairs[pairID] {
+			if err := d.firewall.DeleteFilterRule(rule); err != nil {
+				merr = multierror.Append(merr, fmt.Errorf("rule %s: %w", pairID, err))
+			}
+		}
+		delete(d.peerRulesPairs, pairID)
+	}
+	if err := nberrors.FormatErrorOrNil(merr); err != nil {
+		log.Errorf("rollback peer rules: %v", err)
+	}
+}
+
+func (d *DefaultManager) applyPeerGroup(g *peerRuleGroup) (id.RuleID, []firewall.Rule, error) {
+	protocol, err := ConvertToFirewallProtocol(g.protocol)
+	if err != nil {
+		return "", nil, fmt.Errorf("skipping firewall rule: %w", err)
+	}
+	action, err := convertFirewallAction(g.action)
+	if err != nil {
+		return "", nil, fmt.Errorf("skipping firewall rule: %w", err)
+	}
+	port, err := resolveGroupPort(g)
+	if err != nil {
+		return "", nil, err
+	}
+
+	var fwRule firewall.Rule
+	switch g.direction {
+	case mgmProto.RuleDirection_IN:
+		fwRule, err = d.firewall.AddFilterRule(g.policyID, g.sources, firewall.Network{}, protocol, nil, port, action)
+	case mgmProto.RuleDirection_OUT:
+		if d.firewall.IsStateful() {
+			return "", nil, nil
+		}
+		if shouldSkipInvertedRule(protocol, port) {
+			return "", nil, nil
+		}
+		fwRule, err = d.firewall.AddFilterRule(g.policyID, g.sources, firewall.Network{}, protocol, port, nil, action)
+	default:
+		return "", nil, fmt.Errorf("invalid direction, skipping firewall rule")
+	}
+
+	if err != nil {
+		return "", nil, fmt.Errorf("add firewall rule: %w", err)
+	}
+	if fwRule == nil {
+		return "", nil, fmt.Errorf("add firewall rule: %w", ErrNoRuleReturned)
+	}
+
+	// Derive the pair id from the backend rule, like the route path:
+	// the backend dedups identical content, so two policies authorizing
+	// the same flow resolve to the same id and a single backing rule.
+	return fwRule.ID(), []firewall.Rule{fwRule}, nil
 }
 
 func (d *DefaultManager) applyRouteACLs(rules []*mgmProto.RouteFirewallRule, dynamicResolver bool) error {
-	newRouteRules := make(map[id.RuleID]struct{}, len(rules))
+	newRouteRules := make(map[id.RuleID]firewall.Rule, len(rules))
 	var merr *multierror.Error
 
-	// Apply new rules - firewall manager will return existing rule ID if already present
+	// Apply new rules - firewall manager will return the existing rule if already present
 	for _, rule := range rules {
-		id, err := d.applyRouteACL(rule, dynamicResolver)
+		addedRule, err := d.applyRouteACL(rule, dynamicResolver)
 		if err != nil {
 			if errors.Is(err, ErrSourceRangesEmpty) {
 				log.Debugf("skipping empty sources rule with destination %s: %v", rule.Destination, err)
@@ -163,16 +295,18 @@ func (d *DefaultManager) applyRouteACLs(rules []*mgmProto.RouteFirewallRule, dyn
 			}
 			continue
 		}
-		newRouteRules[id] = struct{}{}
+		newRouteRules[addedRule.ID()] = addedRule
 	}
 
-	// Clean up old firewall rules
-	for id := range d.routeRules {
-		if _, exists := newRouteRules[id]; !exists {
-			if err := d.firewall.DeleteRouteRule(id); err != nil {
-				merr = multierror.Append(merr, fmt.Errorf("delete route rule: %w", err))
-			}
-			// implicitly deleted from the map
+	// Tear down old route rules; retain ones the backend refused so a
+	// transient failure doesn't leave orphaned rules in the firewall.
+	for ruleID, rule := range d.routeRules {
+		if _, exists := newRouteRules[ruleID]; exists {
+			continue
+		}
+		if err := d.firewall.DeleteFilterRule(rule); err != nil {
+			merr = multierror.Append(merr, fmt.Errorf("delete route rule, will retry: %w", err))
+			newRouteRules[ruleID] = rule
 		}
 	}
 
@@ -180,102 +314,196 @@ func (d *DefaultManager) applyRouteACLs(rules []*mgmProto.RouteFirewallRule, dyn
 	return nberrors.FormatErrorOrNil(merr)
 }
 
-func (d *DefaultManager) applyRouteACL(rule *mgmProto.RouteFirewallRule, dynamicResolver bool) (id.RuleID, error) {
+func (d *DefaultManager) applyRouteACL(rule *mgmProto.RouteFirewallRule, dynamicResolver bool) (firewall.Rule, error) {
 	if len(rule.SourceRanges) == 0 {
-		return "", ErrSourceRangesEmpty
+		return nil, ErrSourceRangesEmpty
 	}
 
 	var sources []netip.Prefix
 	for _, sourceRange := range rule.SourceRanges {
 		source, err := netip.ParsePrefix(sourceRange)
 		if err != nil {
-			return "", fmt.Errorf("parse source range: %w", err)
+			return nil, fmt.Errorf("parse source range: %w", err)
 		}
-		sources = append(sources, source)
+		sources = append(sources, firewall.UnmapPrefix(source))
 	}
 
 	destination, err := determineDestination(rule, dynamicResolver, sources)
 	if err != nil {
-		return "", fmt.Errorf("determine destination: %w", err)
+		return nil, fmt.Errorf("determine destination: %w", err)
 	}
 
-	protocol, err := convertToFirewallProtocol(rule.Protocol)
+	protocol, err := ConvertToFirewallProtocol(rule.Protocol)
 	if err != nil {
-		return "", fmt.Errorf("invalid protocol: %w", err)
+		return nil, fmt.Errorf("invalid protocol: %w", err)
 	}
 
 	action, err := convertFirewallAction(rule.Action)
 	if err != nil {
-		return "", fmt.Errorf("invalid action: %w", err)
+		return nil, fmt.Errorf("invalid action: %w", err)
 	}
 
 	dPorts := convertPortInfo(rule.PortInfo)
 
-	addedRule, err := d.firewall.AddRouteFiltering(rule.PolicyID, sources, destination, protocol, nil, dPorts, action)
+	addedRule, err := d.firewall.AddFilterRule(rule.PolicyID, sources, destination, protocol, nil, dPorts, action)
 	if err != nil {
-		return "", fmt.Errorf("add route rule: %w", err)
+		return nil, fmt.Errorf("add route rule: %w", err)
+	}
+	if addedRule == nil {
+		return nil, fmt.Errorf("add route rule: %w", ErrNoRuleReturned)
 	}
 
-	return id.RuleID(addedRule.ID()), nil
+	return addedRule, nil
 }
 
-func (d *DefaultManager) protoRuleToFirewallRule(
-	r *mgmProto.FirewallRule,
-	ipsetName string,
-) (id.RuleID, []firewall.Rule, error) {
-	ip, err := extractRuleIP(r)
-	if err != nil {
-		return "", nil, err
+// splitDenyAccept partitions groups by action so denies can be
+// applied before accepts. Order within each bucket is preserved.
+func splitDenyAccept(groups []*peerRuleGroup) (denies, accepts []*peerRuleGroup) {
+	for _, g := range groups {
+		if g.action == mgmProto.RuleAction_DROP {
+			denies = append(denies, g)
+		} else {
+			accepts = append(accepts, g)
+		}
+	}
+	return denies, accepts
+}
+
+// groupPeerRules merges single-source rules sharing a selector into
+// multi-source groups. It splits source-decode failures by action:
+// denyErr is non-nil when a deny rule could not be decoded, which is a
+// fail-open risk the caller must treat as fatal for the pass; err
+// carries the tolerable accept-rule failures the caller can log and
+// continue past.
+func groupPeerRules(rules []*mgmProto.FirewallRule) (groups []*peerRuleGroup, denyErr error, err error) {
+	var denyMerr, acceptMerr *multierror.Error
+	byKey := make(map[peerRuleKey]*peerRuleGroup)
+	order := make([]peerRuleKey, 0)
+
+	for _, r := range rules {
+		srcs, decErr := extractRuleSources(r)
+		if decErr != nil {
+			if r.Action == mgmProto.RuleAction_DROP {
+				denyMerr = multierror.Append(denyMerr, decErr)
+			} else {
+				acceptMerr = multierror.Append(acceptMerr, decErr)
+			}
+			continue
+		}
+		// A single FirewallRule normally carries one address family, but
+		// split by family defensively: each backend keys a rule to one
+		// family and would mismatch sources of the other, so a group's
+		// sources must never span families.
+		v4, v6 := splitPrefixesByFamily(srcs)
+		for _, sub := range []struct {
+			isV6    bool
+			sources []netip.Prefix
+		}{{false, v4}, {true, v6}} {
+			if len(sub.sources) == 0 {
+				continue
+			}
+			key := ruleGroupKey(r, sub.isV6)
+			g, ok := byKey[key]
+			if !ok {
+				g = &peerRuleGroup{
+					direction:  r.Direction,
+					action:     r.Action,
+					protocol:   r.Protocol,
+					port:       r.PortInfo,
+					legacyPort: r.Port,
+					policyID:   r.PolicyID,
+				}
+				byKey[key] = g
+				order = append(order, key)
+			}
+			g.sources = append(g.sources, sub.sources...)
+		}
 	}
 
-	protocol, err := convertToFirewallProtocol(r.Protocol)
-	if err != nil {
-		return "", nil, fmt.Errorf("skipping firewall rule: %s", err)
+	out := make([]*peerRuleGroup, 0, len(order))
+	for _, k := range order {
+		out = append(out, byKey[k])
+	}
+	return out, nberrors.FormatErrorOrNil(denyMerr), nberrors.FormatErrorOrNil(acceptMerr)
+}
+
+func prefixIsV6(p netip.Prefix) bool {
+	return p.Addr().Is6() && !p.Addr().Is4In6()
+}
+
+// splitPrefixesByFamily partitions prefixes into IPv4 and IPv6 groups.
+func splitPrefixesByFamily(prefixes []netip.Prefix) (v4, v6 []netip.Prefix) {
+	for _, p := range prefixes {
+		if prefixIsV6(p) {
+			v6 = append(v6, p)
+		} else {
+			v4 = append(v4, p)
+		}
+	}
+	return v4, v6
+}
+
+// ruleGroupKey builds the selector key for a rule. v6 must reflect the
+// rule's source family: mgmt emits one rule per family and mixing them
+// would break ICMP-variant selection in uspfilter.
+func ruleGroupKey(r *mgmProto.FirewallRule, v6 bool) peerRuleKey {
+	k := peerRuleKey{
+		v6:         v6,
+		policyID:   string(r.PolicyID),
+		direction:  r.Direction,
+		action:     r.Action,
+		protocol:   r.Protocol,
+		legacyPort: r.Port,
+	}
+	if pi := r.PortInfo; pi != nil {
+		k.port = uint16(pi.GetPort())
+		if rng := pi.GetRange(); rng != nil {
+			k.rangeStart = uint16(rng.GetStart())
+			k.rangeEnd = uint16(rng.GetEnd())
+		}
+	}
+	return k
+}
+
+// extractRuleSources returns all source prefixes the rule applies to.
+// New management populates sourcePrefixes; older management sets PeerIP.
+func extractRuleSources(r *mgmProto.FirewallRule) ([]netip.Prefix, error) {
+	if len(r.SourcePrefixes) > 0 {
+		out := make([]netip.Prefix, 0, len(r.SourcePrefixes))
+		for _, raw := range r.SourcePrefixes {
+			addr, err := netiputil.DecodeAddr(raw)
+			if err != nil {
+				return nil, fmt.Errorf("decode source prefix: %w", err)
+			}
+			out = append(out, netip.PrefixFrom(addr.Unmap(), addr.Unmap().BitLen()))
+		}
+		return out, nil
 	}
 
-	action, err := convertFirewallAction(r.Action)
+	//nolint:staticcheck // PeerIP used for backward compatibility with old management
+	addr, err := netip.ParseAddr(r.PeerIP)
 	if err != nil {
-		return "", nil, fmt.Errorf("skipping firewall rule: %s", err)
+		return nil, fmt.Errorf("invalid IP address, skipping firewall rule")
 	}
+	addr = addr.Unmap()
+	return []netip.Prefix{netip.PrefixFrom(addr, addr.BitLen())}, nil
+}
 
-	var port *firewall.Port
-	if !portInfoEmpty(r.PortInfo) {
-		port = convertPortInfo(r.PortInfo)
-	} else if r.Port != "" {
-		// old version of management, single port
-		value, err := strconv.Atoi(r.Port)
+func resolveGroupPort(g *peerRuleGroup) (*firewall.Port, error) {
+	if !portInfoEmpty(g.port) {
+		return convertPortInfo(g.port), nil
+	}
+	if g.legacyPort != "" {
+		value, err := strconv.ParseUint(g.legacyPort, 10, 16)
 		if err != nil {
-			return "", nil, fmt.Errorf("invalid port: %w", err)
+			return nil, fmt.Errorf("invalid port: %w", err)
 		}
-		port = &firewall.Port{
+		return &firewall.Port{
 			Values: []uint16{uint16(value)},
-		}
+		}, nil
 	}
-
-	ruleID := d.getPeerRuleID(ip, protocol, int(r.Direction), port, action)
-	if rulesPair, ok := d.peerRulesPairs[ruleID]; ok {
-		return ruleID, rulesPair, nil
-	}
-
-	var rules []firewall.Rule
-	switch r.Direction {
-	case mgmProto.RuleDirection_IN:
-		rules, err = d.addInRules(r.PolicyID, ip, protocol, port, action, ipsetName)
-	case mgmProto.RuleDirection_OUT:
-		if d.firewall.IsStateful() {
-			return "", nil, nil
-		}
-		// return traffic for outbound connections if firewall is stateless
-		rules, err = d.addOutRules(r.PolicyID, ip, protocol, port, action, ipsetName)
-	default:
-		return "", nil, fmt.Errorf("invalid direction, skipping firewall rule")
-	}
-
-	if err != nil {
-		return "", nil, err
-	}
-
-	return ruleID, rules, nil
+	// nolint:nilnil // a nil port legitimately means "no port restriction"
+	return nil, nil
 }
 
 func portInfoEmpty(portInfo *mgmProto.PortInfo) bool {
@@ -294,85 +522,9 @@ func portInfoEmpty(portInfo *mgmProto.PortInfo) bool {
 	}
 }
 
-func (d *DefaultManager) addInRules(
-	id []byte,
-	ip netip.Addr,
-	protocol firewall.Protocol,
-	port *firewall.Port,
-	action firewall.Action,
-	ipsetName string,
-) ([]firewall.Rule, error) {
-	rule, err := d.firewall.AddPeerFiltering(id, ip.AsSlice(), protocol, nil, port, action, ipsetName)
-	if err != nil {
-		return nil, fmt.Errorf("add firewall rule: %w", err)
-	}
-
-	return rule, nil
-}
-
-func (d *DefaultManager) addOutRules(
-	id []byte,
-	ip netip.Addr,
-	protocol firewall.Protocol,
-	port *firewall.Port,
-	action firewall.Action,
-	ipsetName string,
-) ([]firewall.Rule, error) {
-	if shouldSkipInvertedRule(protocol, port) {
-		return nil, nil
-	}
-
-	rule, err := d.firewall.AddPeerFiltering(id, ip.AsSlice(), protocol, port, nil, action, ipsetName)
-	if err != nil {
-		return nil, fmt.Errorf("add firewall rule: %w", err)
-	}
-
-	return rule, nil
-}
-
-// getPeerRuleID returns unique ID for the rule based on its parameters.
-func (d *DefaultManager) getPeerRuleID(
-	ip netip.Addr,
-	proto firewall.Protocol,
-	direction int,
-	port *firewall.Port,
-	action firewall.Action,
-) id.RuleID {
-	idStr := ip.String() + string(proto) + strconv.Itoa(direction) + strconv.Itoa(int(action))
-	if port != nil {
-		idStr += port.String()
-	}
-
-	return id.RuleID(hex.EncodeToString(md5.New().Sum([]byte(idStr))))
-}
-
-// getRuleGroupingSelector takes all rule properties except IP address to build selector
-func (d *DefaultManager) getRuleGroupingSelector(rule *mgmProto.FirewallRule) string {
-	return fmt.Sprintf("%v:%v:%v:%s:%v", strconv.Itoa(int(rule.Direction)), rule.Action, rule.Protocol, rule.Port, rule.PortInfo)
-}
-
-
-// extractRuleIP extracts the peer IP from a firewall rule.
-// If sourcePrefixes is populated (new management), decode the first entry and use its address.
-// Otherwise fall back to the deprecated PeerIP string field (old management).
-func extractRuleIP(r *mgmProto.FirewallRule) (netip.Addr, error) {
-	if len(r.SourcePrefixes) > 0 {
-		addr, err := netiputil.DecodeAddr(r.SourcePrefixes[0])
-		if err != nil {
-			return netip.Addr{}, fmt.Errorf("decode source prefix: %w", err)
-		}
-		return addr.Unmap(), nil
-	}
-
-	//nolint:staticcheck // PeerIP used for backward compatibility with old management
-	addr, err := netip.ParseAddr(r.PeerIP)
-	if err != nil {
-		return netip.Addr{}, fmt.Errorf("invalid IP address, skipping firewall rule")
-	}
-	return addr.Unmap(), nil
-}
-
-func convertToFirewallProtocol(protocol mgmProto.RuleProtocol) (firewall.Protocol, error) {
+// ConvertToFirewallProtocol maps a management rule protocol to the
+// firewall protocol type.
+func ConvertToFirewallProtocol(protocol mgmProto.RuleProtocol) (firewall.Protocol, error) {
 	switch protocol {
 	case mgmProto.RuleProtocol_TCP:
 		return firewall.ProtocolTCP, nil

client/internal/acl/manager_test.go

@@ -9,6 +9,7 @@ import (
 	"github.com/stretchr/testify/require"
 
 	"github.com/netbirdio/netbird/client/firewall"
+	fwmanager "github.com/netbirdio/netbird/client/firewall/manager"
 	"github.com/netbirdio/netbird/client/iface"
 	"github.com/netbirdio/netbird/client/iface/wgaddr"
 	"github.com/netbirdio/netbird/client/internal/acl/mocks"
@@ -76,9 +77,9 @@ func TestDefaultManager(t *testing.T) {
 	})
 
 	t.Run("add extra rules", func(t *testing.T) {
-		existedPairs := map[string]struct{}{}
+		existedPairs := map[fwmanager.RuleID]struct{}{}
 		for id := range acl.peerRulesPairs {
-			existedPairs[id.ID()] = struct{}{}
+			existedPairs[id] = struct{}{}
 		}
 
 		// remove first rule
@@ -105,7 +106,7 @@ func TestDefaultManager(t *testing.T) {
 		// check that old rule was removed
 		previousCount := 0
 		for id := range acl.peerRulesPairs {
-			if _, ok := existedPairs[id.ID()]; ok {
+			if _, ok := existedPairs[id]; ok {
 				previousCount++
 			}
 		}

client/internal/auth/pkce_flow.go

@@ -360,7 +360,13 @@ func isRedirectURLPortUsed(redirectURL string, excludedRanges []excludedPortRang
 		return true
 	}
 
-	addr := fmt.Sprintf(":%s", port)
+	// FreeBSD 15 disables connecting to INADDR_ANY (0.0.0.0) as a localhost
+	// alias by default, ensure explicit ip for localhost.
+	host := parsedURL.Hostname()
+	if host == "" {
+		host = "127.0.0.1"
+	}
+	addr := net.JoinHostPort(host, port)
 	conn, err := net.DialTimeout("tcp", addr, 3*time.Second)
 	if err != nil {
 		return false

client/internal/connect.go

@@ -116,7 +116,6 @@ func (c *ConnectClient) RunOniOS(
 	fileDescriptor int32,
 	networkChangeListener listener.NetworkChangeListener,
 	dnsManager dns.IosDnsManager,
-	dnsAddresses []netip.AddrPort,
 	stateFilePath string,
 ) error {
 	// Set GC percent to 5% to reduce memory usage as iOS only allows 50MB of memory for the extension.
@@ -126,7 +125,6 @@ func (c *ConnectClient) RunOniOS(
 		FileDescriptor:        fileDescriptor,
 		NetworkChangeListener: networkChangeListener,
 		DnsManager:            dnsManager,
-		HostDNSAddresses:      dnsAddresses,
 		StateFilePath:         stateFilePath,
 	}
 	return c.run(mobileDependency, nil, "")

client/internal/debug/debug.go

@@ -45,8 +45,11 @@ netbird.out: Most recent, anonymized stdout log file of the NetBird client.
 routes.txt: Detailed system routing table in tabular format including destination, gateway, interface, metrics, and protocol information, if --system-info flag was provided.
 interfaces.txt: Anonymized network interface information, if --system-info flag was provided.
 ip_rules.txt: Detailed IP routing rules in tabular format including priority, source, destination, interfaces, table, and action information (Linux only), if --system-info flag was provided.
-iptables.txt: Anonymized iptables rules with packet counters, if --system-info flag was provided.
-nftables.txt: Anonymized nftables rules with packet counters, if --system-info flag was provided.
+iptables.txt: Anonymized iptables (IPv4) rules with packet counters, if --system-info flag was provided.
+ip6tables.txt: Anonymized ip6tables (IPv6) rules with packet counters, if --system-info flag was provided.
+ipset.txt: Anonymized ipset list output, if --system-info flag was provided.
+nftables.txt: Anonymized nftables rules with packet counters across all families (ip, ip6, inet, etc.), if --system-info flag was provided.
+sysctls.txt: Forwarding, reverse-path filter, source-validation, and conntrack accounting sysctl values that the NetBird client may read or modify, if --system-info flag was provided (Linux only).
 resolv.conf: DNS resolver configuration from /etc/resolv.conf (Unix systems only), if --system-info flag was provided.
 scutil_dns.txt: DNS configuration from scutil --dns (macOS only), if --system-info flag was provided.
 resolved_domains.txt: Anonymized resolved domain IP addresses from the status recorder.
@@ -165,22 +168,33 @@ The config.txt file contains anonymized configuration information of the NetBird
 Other non-sensitive configuration options are included without anonymization.
 
 Firewall Rules (Linux only)
-The bundle includes two separate firewall rule files:
+The bundle includes the following firewall-related files:
 
 iptables.txt:
-- Complete iptables ruleset with packet counters using 'iptables -v -n -L'
+- IPv4 iptables ruleset with packet counters using 'iptables-save' and 'iptables -v -n -L'
 - Includes all tables (filter, nat, mangle, raw, security)
 - Shows packet and byte counters for each rule
 - All IP addresses are anonymized
 - Chain names, table names, and other non-sensitive information remain unchanged
 
+ip6tables.txt:
+- IPv6 ip6tables ruleset with packet counters using 'ip6tables-save' and 'ip6tables -v -n -L'
+- Same table coverage and anonymization as iptables.txt
+- Omitted when ip6tables is not installed or no IPv6 rules are present
+
+ipset.txt:
+- Output of 'ipset list' (family-agnostic)
+- IP addresses are anonymized; set names and types remain unchanged
+
 nftables.txt:
-- Complete nftables ruleset obtained via 'nft -a list ruleset'
+- Complete nftables ruleset across all families (ip, ip6, inet, arp, bridge, netdev) via 'nft -a list ruleset'
 - Includes rule handle numbers and packet counters
-- All tables, chains, and rules are included
-- Shows packet and byte counters for each rule
-- All IP addresses are anonymized
-- Chain names, table names, and other non-sensitive information remain unchanged
+- All IP addresses are anonymized; chain/table names remain unchanged
+
+sysctls.txt:
+- Forwarding (IPv4 + IPv6, global and per-interface), reverse-path filter, source-validation, conntrack accounting, and TCP-related sysctls that netbird may read or modify
+- Per-interface keys are enumerated from /proc/sys/net/ipv{4,6}/conf
+- Interface names anonymized when --anonymize is set
 
 IP Rules (Linux only)
 The ip_rules.txt file contains detailed IP routing rule information:
@@ -412,6 +426,10 @@ func (g *BundleGenerator) addSystemInfo() {
 		log.Errorf("failed to add firewall rules to debug bundle: %v", err)
 	}
 
+	if err := g.addSysctls(); err != nil {
+		log.Errorf("failed to add sysctls to debug bundle: %v", err)
+	}
+
 	if err := g.addDNSInfo(); err != nil {
 		log.Errorf("failed to add DNS info to debug bundle: %v", err)
 	}

client/internal/debug/debug_linux.go

@@ -124,15 +124,18 @@ func getSystemdLogs(serviceName string) (string, error) {
 // addFirewallRules collects and adds firewall rules to the archive
 func (g *BundleGenerator) addFirewallRules() error {
 	log.Info("Collecting firewall rules")
-	iptablesRules, err := collectIPTablesRules()
+	g.addIPTablesRulesToBundle("iptables-save", "iptables", "iptables.txt")
+	g.addIPTablesRulesToBundle("ip6tables-save", "ip6tables", "ip6tables.txt")
+
+	ipsetOutput, err := collectIPSets()
 	if err != nil {
-		log.Warnf("Failed to collect iptables rules: %v", err)
+		log.Warnf("Failed to collect ipset information: %v", err)
 	} else {
 		if g.anonymize {
-			iptablesRules = g.anonymizer.AnonymizeString(iptablesRules)
+			ipsetOutput = g.anonymizer.AnonymizeString(ipsetOutput)
 		}
-		if err := g.addFileToZip(strings.NewReader(iptablesRules), "iptables.txt"); err != nil {
-			log.Warnf("Failed to add iptables rules to bundle: %v", err)
+		if err := g.addFileToZip(strings.NewReader(ipsetOutput), "ipset.txt"); err != nil {
+			log.Warnf("Failed to add ipset output to bundle: %v", err)
 		}
 	}
 
@@ -151,44 +154,65 @@ func (g *BundleGenerator) addFirewallRules() error {
 	return nil
 }
 
-// collectIPTablesRules collects rules using both iptables-save and verbose listing
-func collectIPTablesRules() (string, error) {
-	var builder strings.Builder
-
-	saveOutput, err := collectIPTablesSave()
+// addIPTablesRulesToBundle collects iptables/ip6tables rules and writes them to the bundle.
+func (g *BundleGenerator) addIPTablesRulesToBundle(saveBin, listBin, filename string) {
+	rules, err := collectIPTablesRules(saveBin, listBin)
 	if err != nil {
-		log.Warnf("Failed to collect iptables rules using iptables-save: %v", err)
-	} else {
-		builder.WriteString("=== iptables-save output ===\n")
+		log.Warnf("Failed to collect %s rules: %v", listBin, err)
+		return
+	}
+	if g.anonymize {
+		rules = g.anonymizer.AnonymizeString(rules)
+	}
+	if err := g.addFileToZip(strings.NewReader(rules), filename); err != nil {
+		log.Warnf("Failed to add %s rules to bundle: %v", listBin, err)
+	}
+}
+
+// collectIPTablesRules collects rules using both <saveBin> and verbose listing via <listBin>.
+// Returns an error when neither command produced any output (e.g. the binary is missing),
+// so the caller can skip writing an empty file.
+func collectIPTablesRules(saveBin, listBin string) (string, error) {
+	var builder strings.Builder
+	var collected bool
+	var firstErr error
+
+	saveOutput, err := runCommand(saveBin)
+	switch {
+	case err != nil:
+		firstErr = err
+		log.Warnf("Failed to collect %s output: %v", saveBin, err)
+	case strings.TrimSpace(saveOutput) == "":
+		log.Debugf("%s produced no output, skipping", saveBin)
+	default:
+		builder.WriteString(fmt.Sprintf("=== %s output ===\n", saveBin))
 		builder.WriteString(saveOutput)
 		builder.WriteString("\n")
+		collected = true
 	}
 
-	ipsetOutput, err := collectIPSets()
-	if err != nil {
-		log.Warnf("Failed to collect ipset information: %v", err)
-	} else {
-		builder.WriteString("=== ipset list output ===\n")
-		builder.WriteString(ipsetOutput)
-		builder.WriteString("\n")
-	}
-
-	builder.WriteString("=== iptables -v -n -L output ===\n")
+	listHeader := fmt.Sprintf("=== %s -v -n -L output ===\n", listBin)
+	builder.WriteString(listHeader)
 
 	tables := []string{"filter", "nat", "mangle", "raw", "security"}
-
 	for _, table := range tables {
-		builder.WriteString(fmt.Sprintf("*%s\n", table))
-
-		stats, err := getTableStatistics(table)
+		stats, err := runCommand(listBin, "-v", "-n", "-L", "-t", table)
 		if err != nil {
-			log.Warnf("Failed to get statistics for table %s: %v", table, err)
+			if firstErr == nil {
+				firstErr = err
+			}
+			log.Warnf("Failed to get %s statistics for table %s: %v", listBin, table, err)
 			continue
 		}
+		builder.WriteString(fmt.Sprintf("*%s\n", table))
 		builder.WriteString(stats)
 		builder.WriteString("\n")
+		collected = true
 	}
 
+	if !collected {
+		return "", fmt.Errorf("collect %s rules: %w", listBin, firstErr)
+	}
 	return builder.String(), nil
 }
 
@@ -214,34 +238,15 @@ func collectIPSets() (string, error) {
 	return ipsets, nil
 }
 
-// collectIPTablesSave uses iptables-save to get rule definitions
-func collectIPTablesSave() (string, error) {
-	cmd := exec.Command("iptables-save")
+// runCommand executes a command and returns its stdout, wrapping stderr in the error on failure.
+func runCommand(name string, args ...string) (string, error) {
+	cmd := exec.Command(name, args...)
 	var stdout, stderr bytes.Buffer
 	cmd.Stdout = &stdout
 	cmd.Stderr = &stderr
 
 	if err := cmd.Run(); err != nil {
-		return "", fmt.Errorf("execute iptables-save: %w (stderr: %s)", err, stderr.String())
-	}
-
-	rules := stdout.String()
-	if strings.TrimSpace(rules) == "" {
-		return "", fmt.Errorf("no iptables rules found")
-	}
-
-	return rules, nil
-}
-
-// getTableStatistics gets verbose statistics for an entire table using iptables command
-func getTableStatistics(table string) (string, error) {
-	cmd := exec.Command("iptables", "-v", "-n", "-L", "-t", table)
-	var stdout, stderr bytes.Buffer
-	cmd.Stdout = &stdout
-	cmd.Stderr = &stderr
-
-	if err := cmd.Run(); err != nil {
-		return "", fmt.Errorf("execute iptables -v -n -L: %w (stderr: %s)", err, stderr.String())
+		return "", fmt.Errorf("execute %s: %w (stderr: %s)", name, err, stderr.String())
 	}
 
 	return stdout.String(), nil
@@ -804,3 +809,91 @@ func formatSetKeyType(keyType nftables.SetDatatype) string {
 		return fmt.Sprintf("type-%v", keyType)
 	}
 }
+
+// addSysctls collects forwarding and netbird-managed sysctl values and writes them to the bundle.
+func (g *BundleGenerator) addSysctls() error {
+	log.Info("Collecting sysctls")
+	content := collectSysctls()
+	if g.anonymize {
+		content = g.anonymizer.AnonymizeString(content)
+	}
+	if err := g.addFileToZip(strings.NewReader(content), "sysctls.txt"); err != nil {
+		return fmt.Errorf("add sysctls to bundle: %w", err)
+	}
+	return nil
+}
+
+// collectSysctls reads every sysctl that the netbird client may modify, plus
+// global IPv4/IPv6 forwarding, and returns a formatted dump grouped by topic.
+// Per-interface values are enumerated by listing /proc/sys/net/ipv{4,6}/conf.
+func collectSysctls() string {
+	var builder strings.Builder
+
+	writeSysctlGroup(&builder, "forwarding", []string{
+		"net.ipv4.ip_forward",
+		"net.ipv6.conf.all.forwarding",
+		"net.ipv6.conf.default.forwarding",
+	})
+	writeSysctlGroup(&builder, "ipv4 per-interface forwarding", listInterfaceSysctls("ipv4", "forwarding"))
+	writeSysctlGroup(&builder, "ipv6 per-interface forwarding", listInterfaceSysctls("ipv6", "forwarding"))
+	writeSysctlGroup(&builder, "rp_filter", append(
+		[]string{"net.ipv4.conf.all.rp_filter", "net.ipv4.conf.default.rp_filter"},
+		listInterfaceSysctls("ipv4", "rp_filter")...,
+	))
+	writeSysctlGroup(&builder, "src_valid_mark", append(
+		[]string{"net.ipv4.conf.all.src_valid_mark", "net.ipv4.conf.default.src_valid_mark"},
+		listInterfaceSysctls("ipv4", "src_valid_mark")...,
+	))
+	writeSysctlGroup(&builder, "conntrack", []string{
+		"net.netfilter.nf_conntrack_acct",
+		"net.netfilter.nf_conntrack_tcp_loose",
+	})
+	writeSysctlGroup(&builder, "tcp", []string{
+		"net.ipv4.tcp_tw_reuse",
+	})
+
+	return builder.String()
+}
+
+func writeSysctlGroup(builder *strings.Builder, title string, keys []string) {
+	builder.WriteString(fmt.Sprintf("=== %s ===\n", title))
+	for _, key := range keys {
+		value, err := readSysctl(key)
+		if err != nil {
+			builder.WriteString(fmt.Sprintf("%s = <error: %v>\n", key, err))
+			continue
+		}
+		builder.WriteString(fmt.Sprintf("%s = %s\n", key, value))
+	}
+	builder.WriteString("\n")
+}
+
+// listInterfaceSysctls returns net.ipvX.conf.<iface>.<leaf> keys for every
+// interface present in /proc/sys/net/ipvX/conf, skipping "all" and "default"
+// (callers add those explicitly so they appear first).
+func listInterfaceSysctls(family, leaf string) []string {
+	dir := fmt.Sprintf("/proc/sys/net/%s/conf", family)
+	entries, err := os.ReadDir(dir)
+	if err != nil {
+		return nil
+	}
+	var keys []string
+	for _, e := range entries {
+		name := e.Name()
+		if name == "all" || name == "default" {
+			continue
+		}
+		keys = append(keys, fmt.Sprintf("net.%s.conf.%s.%s", family, name, leaf))
+	}
+	sort.Strings(keys)
+	return keys
+}
+
+func readSysctl(key string) (string, error) {
+	path := fmt.Sprintf("/proc/sys/%s", strings.ReplaceAll(key, ".", "/"))
+	value, err := os.ReadFile(path)
+	if err != nil {
+		return "", err
+	}
+	return strings.TrimSpace(string(value)), nil
+}

client/internal/debug/debug_nonlinux.go

@@ -17,3 +17,8 @@ func (g *BundleGenerator) addIPRules() error {
 	// IP rules are only supported on Linux
 	return nil
 }
+
+func (g *BundleGenerator) addSysctls() error {
+	// Sysctl collection is only supported on Linux
+	return nil
+}

client/internal/dns/handler_chain.go

@@ -339,8 +339,7 @@ func (c *HandlerChain) isHandlerMatch(qname string, entry HandlerEntry) bool {
 	case entry.Pattern == ".":
 		return true
 	case entry.IsWildcard:
-		parts := strings.Split(strings.TrimSuffix(qname, entry.Pattern), ".")
-		return len(parts) >= 2 && strings.HasSuffix(qname, entry.Pattern)
+		return strings.HasSuffix(qname, "."+entry.Pattern)
 	default:
 		// For non-wildcard patterns:
 		// If handler wants subdomain matching, allow suffix match

client/internal/dns/handler_chain_test.go

@@ -164,6 +164,54 @@ func TestHandlerChain_ServeDNS_DomainMatching(t *testing.T) {
 			matchSubdomains: true,
 			shouldMatch:     true,
 		},
+		{
+			name:            "wildcard label-boundary mismatch (suffix overlap)",
+			handlerDomain:   "*.b.test.",
+			queryDomain:     "x.ab.test.",
+			isWildcard:      true,
+			matchSubdomains: false,
+			shouldMatch:     false,
+		},
+		{
+			name:            "wildcard label-boundary match",
+			handlerDomain:   "*.b.test.",
+			queryDomain:     "x.b.test.",
+			isWildcard:      true,
+			matchSubdomains: false,
+			shouldMatch:     true,
+		},
+		{
+			name:            "wildcard multi-label match",
+			handlerDomain:   "*.b.test.",
+			queryDomain:     "x.y.b.test.",
+			isWildcard:      true,
+			matchSubdomains: false,
+			shouldMatch:     true,
+		},
+		{
+			name:            "wildcard no match on multi-label apex",
+			handlerDomain:   "*.b.test.",
+			queryDomain:     "b.test.",
+			isWildcard:      true,
+			matchSubdomains: false,
+			shouldMatch:     false,
+		},
+		{
+			name:            "wildcard no match on unrelated suffix containment",
+			handlerDomain:   "*.example.com.",
+			queryDomain:     "notexample.com.",
+			isWildcard:      true,
+			matchSubdomains: false,
+			shouldMatch:     false,
+		},
+		{
+			name:            "wildcard accepts pattern registered without trailing dot",
+			handlerDomain:   "*.b.test",
+			queryDomain:     "x.b.test.",
+			isWildcard:      true,
+			matchSubdomains: false,
+			shouldMatch:     true,
+		},
 	}
 
 	for _, tt := range tests {
@@ -273,6 +321,19 @@ func TestHandlerChain_ServeDNS_OverlappingDomains(t *testing.T) {
 			expectedCalls:   1,
 			expectedHandler: 2, // highest priority matching handler should be called
 		},
+		{
+			name: "overlapping wildcard suffixes route to correct handler",
+			handlers: []struct {
+				pattern  string
+				priority int
+			}{
+				{pattern: "*.b.test.", priority: nbdns.PriorityDNSRoute},
+				{pattern: "*.ab.test.", priority: nbdns.PriorityDNSRoute},
+			},
+			queryDomain:     "app.ab.test.",
+			expectedCalls:   1,
+			expectedHandler: 1,
+		},
 		{
 			name: "root zone with specific domain",
 			handlers: []struct {

client/internal/dns/host.go

@@ -16,6 +16,10 @@ type hostManager interface {
 	restoreHostDNS() error
 	supportCustomPort() bool
 	string() string
+	// getOriginalNameservers returns the OS-side resolvers used as PriorityFallback
+	// upstreams: pre-takeover snapshots on desktop, the OS-pushed list on Android,
+	// hardcoded Quad9 on iOS, nil for noop / mock.
+	getOriginalNameservers() []netip.Addr
 }
 
 type SystemDNSSettings struct {
@@ -131,3 +135,11 @@ func (n noopHostConfigurator) supportCustomPort() bool {
 func (n noopHostConfigurator) string() string {
 	return "noop"
 }
+
+func (n noopHostConfigurator) getOriginalNameservers() []netip.Addr {
+	return nil
+}
+
+func (m *mockHostConfigurator) getOriginalNameservers() []netip.Addr {
+	return nil
+}

client/internal/dns/host_android.go

@@ -1,14 +1,20 @@
 package dns
 
 import (
+	"net/netip"
+
 	"github.com/netbirdio/netbird/client/internal/statemanager"
 )
 
+// androidHostManager is a noop on the OS side (Android's VPN service handles
+// DNS for us) but tracks the OS-reported resolver list pushed via
+// OnUpdatedHostDNSServer so it can serve as the fallback nameserver source.
 type androidHostManager struct {
+	holder *hostsDNSHolder
 }
 
-func newHostManager() (*androidHostManager, error) {
-	return &androidHostManager{}, nil
+func newHostManager(holder *hostsDNSHolder) (*androidHostManager, error) {
+	return &androidHostManager{holder: holder}, nil
 }
 
 func (a androidHostManager) applyDNSConfig(HostDNSConfig, *statemanager.Manager) error {
@@ -26,3 +32,12 @@ func (a androidHostManager) supportCustomPort() bool {
 func (a androidHostManager) string() string {
 	return "none"
 }
+
+func (a androidHostManager) getOriginalNameservers() []netip.Addr {
+	hosts := a.holder.get()
+	out := make([]netip.Addr, 0, len(hosts))
+	for ap := range hosts {
+		out = append(out, ap.Addr())
+	}
+	return out
+}

client/internal/dns/host_ios.go

@@ -3,6 +3,7 @@ package dns
 import (
 	"encoding/json"
 	"fmt"
+	"net/netip"
 
 	log "github.com/sirupsen/logrus"
 
@@ -20,6 +21,14 @@ func newHostManager(dnsManager IosDnsManager) (*iosHostManager, error) {
 	}, nil
 }
 
+func (a iosHostManager) getOriginalNameservers() []netip.Addr {
+	// Quad9 v4+v6: 9.9.9.9, 2620:fe::fe.
+	return []netip.Addr{
+		netip.AddrFrom4([4]byte{9, 9, 9, 9}),
+		netip.AddrFrom16([16]byte{0x26, 0x20, 0x00, 0xfe, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0xfe}),
+	}
+}
+
 func (a iosHostManager) applyDNSConfig(config HostDNSConfig, _ *statemanager.Manager) error {
 	jsonData, err := json.Marshal(config)
 	if err != nil {

client/internal/dns/host_windows.go

@@ -7,6 +7,7 @@ import (
 	"io"
 	"net/netip"
 	"os/exec"
+	"slices"
 	"strings"
 	"syscall"
 	"time"
@@ -44,9 +45,11 @@ const (
 
 	nrptMaxDomainsPerRule = 50
 
-	interfaceConfigPath          = `SYSTEM\CurrentControlSet\Services\Tcpip\Parameters\Interfaces`
-	interfaceConfigNameServerKey = "NameServer"
-	interfaceConfigSearchListKey = "SearchList"
+	interfaceConfigPath           = `SYSTEM\CurrentControlSet\Services\Tcpip\Parameters\Interfaces`
+	interfaceConfigPathV6         = `SYSTEM\CurrentControlSet\Services\Tcpip6\Parameters\Interfaces`
+	interfaceConfigNameServerKey  = "NameServer"
+	interfaceConfigDhcpNameSrvKey = "DhcpNameServer"
+	interfaceConfigSearchListKey  = "SearchList"
 
 	// Network interface DNS registration settings
 	disableDynamicUpdateKey           = "DisableDynamicUpdate"
@@ -67,10 +70,11 @@ const (
 )
 
 type registryConfigurator struct {
-	guid           string
-	routingAll     bool
-	gpo            bool
-	nrptEntryCount int
+	guid            string
+	routingAll      bool
+	gpo             bool
+	nrptEntryCount  int
+	origNameservers []netip.Addr
 }
 
 func newHostManager(wgInterface WGIface) (*registryConfigurator, error) {
@@ -94,6 +98,17 @@ func newHostManager(wgInterface WGIface) (*registryConfigurator, error) {
 		gpo:  useGPO,
 	}
 
+	origNameservers, err := configurator.captureOriginalNameservers()
+	switch {
+	case err != nil:
+		log.Warnf("capture original nameservers from non-WG adapters: %v", err)
+	case len(origNameservers) == 0:
+		log.Warnf("no original nameservers captured from non-WG adapters; DNS fallback will be empty")
+	default:
+		log.Debugf("captured %d original nameservers from non-WG adapters: %v", len(origNameservers), origNameservers)
+	}
+	configurator.origNameservers = origNameservers
+
 	if err := configurator.configureInterface(); err != nil {
 		log.Errorf("failed to configure interface settings: %v", err)
 	}
@@ -101,6 +116,98 @@ func newHostManager(wgInterface WGIface) (*registryConfigurator, error) {
 	return configurator, nil
 }
 
+// captureOriginalNameservers reads DNS addresses from every Tcpip(6) interface
+// registry key except the WG adapter. v4 and v6 servers live in separate
+// hives (Tcpip vs Tcpip6) keyed by the same interface GUID.
+func (r *registryConfigurator) captureOriginalNameservers() ([]netip.Addr, error) {
+	seen := make(map[netip.Addr]struct{})
+	var out []netip.Addr
+	var merr *multierror.Error
+	for _, root := range []string{interfaceConfigPath, interfaceConfigPathV6} {
+		addrs, err := r.captureFromTcpipRoot(root)
+		if err != nil {
+			merr = multierror.Append(merr, fmt.Errorf("%s: %w", root, err))
+			continue
+		}
+		for _, addr := range addrs {
+			if _, dup := seen[addr]; dup {
+				continue
+			}
+			seen[addr] = struct{}{}
+			out = append(out, addr)
+		}
+	}
+	return out, nberrors.FormatErrorOrNil(merr)
+}
+
+func (r *registryConfigurator) captureFromTcpipRoot(rootPath string) ([]netip.Addr, error) {
+	root, err := registry.OpenKey(registry.LOCAL_MACHINE, rootPath, registry.READ)
+	if err != nil {
+		return nil, fmt.Errorf("open key: %w", err)
+	}
+	defer closer(root)
+
+	guids, err := root.ReadSubKeyNames(-1)
+	if err != nil {
+		return nil, fmt.Errorf("read subkeys: %w", err)
+	}
+
+	var out []netip.Addr
+	for _, guid := range guids {
+		if strings.EqualFold(guid, r.guid) {
+			continue
+		}
+		out = append(out, readInterfaceNameservers(rootPath, guid)...)
+	}
+	return out, nil
+}
+
+func readInterfaceNameservers(rootPath, guid string) []netip.Addr {
+	keyPath := rootPath + "\\" + guid
+	k, err := registry.OpenKey(registry.LOCAL_MACHINE, keyPath, registry.QUERY_VALUE)
+	if err != nil {
+		return nil
+	}
+	defer closer(k)
+
+	// Static NameServer wins over DhcpNameServer for actual resolution.
+	for _, name := range []string{interfaceConfigNameServerKey, interfaceConfigDhcpNameSrvKey} {
+		raw, _, err := k.GetStringValue(name)
+		if err != nil || raw == "" {
+			continue
+		}
+		if out := parseRegistryNameservers(raw); len(out) > 0 {
+			return out
+		}
+	}
+	return nil
+}
+
+func parseRegistryNameservers(raw string) []netip.Addr {
+	var out []netip.Addr
+	for _, field := range strings.FieldsFunc(raw, func(r rune) bool { return r == ',' || r == ' ' || r == '\t' }) {
+		addr, err := netip.ParseAddr(strings.TrimSpace(field))
+		if err != nil {
+			continue
+		}
+		addr = addr.Unmap()
+		if !addr.IsValid() || addr.IsUnspecified() {
+			continue
+		}
+		// Drop unzoned link-local: not routable without a scope id. If
+		// the user wrote "fe80::1%eth0" ParseAddr preserves the zone.
+		if addr.IsLinkLocalUnicast() && addr.Zone() == "" {
+			continue
+		}
+		out = append(out, addr)
+	}
+	return out
+}
+
+func (r *registryConfigurator) getOriginalNameservers() []netip.Addr {
+	return slices.Clone(r.origNameservers)
+}
+
 func (r *registryConfigurator) supportCustomPort() bool {
 	return false
 }

client/internal/dns/hosts_dns_holder.go

@@ -25,6 +25,7 @@ func (h *hostsDNSHolder) set(list []netip.AddrPort) {
 	h.mutex.Unlock()
 }
 
+//nolint:unused
 func (h *hostsDNSHolder) get() map[netip.AddrPort]struct{} {
 	h.mutex.RLock()
 	l := h.unprotectedDNSList

client/internal/dns/local/local.go

@@ -26,6 +26,19 @@ type resolver interface {
 	LookupNetIP(ctx context.Context, network, host string) ([]netip.Addr, error)
 }
 
+// PeerConnectivity reports whether a tunnel IP belongs to a peer the
+// client knows about and whether that peer is currently connected. The
+// local resolver uses this to suppress A/AAAA answers whose RDATA points
+// at a disconnected peer (typical case: a synthesized private-service
+// record pointing at an embedded proxy peer that just went offline).
+//
+// known=false means the IP isn't in the local peerstore at all — the
+// record is left alone (it points at something outside our mesh, e.g.
+// a non-peer upstream).
+type PeerConnectivity interface {
+	IsConnectedByIP(ip string) (known, connected bool)
+}
+
 type Resolver struct {
 	mu      sync.RWMutex
 	records map[dns.Question][]dns.RR
@@ -33,6 +46,11 @@ type Resolver struct {
 	// zones maps zone domain -> NonAuthoritative (true = non-authoritative, user-created zone)
 	zones    map[domain.Domain]bool
 	resolver resolver
+	// peerConn, when non-nil, is consulted on every A/AAAA answer to
+	// drop records pointing at disconnected peers. nil disables the
+	// filter and preserves the legacy "return whatever is registered"
+	// behaviour for callers that never wire a status source.
+	peerConn PeerConnectivity
 
 	ctx    context.Context
 	cancel context.CancelFunc
@@ -49,6 +67,15 @@ func NewResolver() *Resolver {
 	}
 }
 
+// SetPeerConnectivity wires the per-IP connectivity check used to filter
+// out A/AAAA answers pointing at disconnected peers. Pass nil to disable.
+// Safe to call multiple times; the latest value wins.
+func (d *Resolver) SetPeerConnectivity(p PeerConnectivity) {
+	d.mu.Lock()
+	defer d.mu.Unlock()
+	d.peerConn = p
+}
+
 func (d *Resolver) MatchSubdomains() bool {
 	return true
 }
@@ -76,8 +103,6 @@ func (d *Resolver) ID() types.HandlerID {
 	return "local-resolver"
 }
 
-func (d *Resolver) ProbeAvailability(context.Context) {}
-
 // ServeDNS handles a DNS request
 func (d *Resolver) ServeDNS(w dns.ResponseWriter, r *dns.Msg) {
 	logger := log.WithFields(log.Fields{
@@ -97,6 +122,7 @@ func (d *Resolver) ServeDNS(w dns.ResponseWriter, r *dns.Msg) {
 	replyMessage.RecursionAvailable = true
 
 	result := d.lookupRecords(logger, question)
+	result.records = d.filterDisconnectedPeerAnswers(logger, question, result.records)
 	replyMessage.Authoritative = !result.hasExternalData
 	replyMessage.Answer = result.records
 	replyMessage.Rcode = d.determineRcode(question, result)
@@ -438,6 +464,78 @@ func (d *Resolver) logDNSError(logger *log.Entry, hostname string, qtype uint16,
 	}
 }
 
+// filterDisconnectedPeerAnswers drops A/AAAA records whose RDATA matches
+// a known but disconnected peer. The synthesized private-service zones
+// emit one A record per connected proxy peer in a cluster; when a peer
+// goes offline, the server-side refresh removes the record from the
+// next netmap, but the client may still hold the previous netmap for a
+// short window. This filter is the local belt to that braces — even on
+// the stale netmap, the resolver hides the offline target.
+//
+// Records pointing at unknown IPs (outside the local peerstore, e.g.
+// non-mesh upstreams) are never dropped. Non-A/AAAA records pass
+// through untouched.
+//
+// Escape hatch: if filtering would leave the answer empty AND at least
+// one record was filtered, the original list is returned. Better to
+// hand the client a record that may not respond than NXDOMAIN it
+// completely when every proxy peer is offline (the upstream may still
+// be reachable some other way, or the peerstore may be stale).
+func (d *Resolver) filterDisconnectedPeerAnswers(logger *log.Entry, question dns.Question, records []dns.RR) []dns.RR {
+	if len(records) == 0 {
+		return records
+	}
+	d.mu.RLock()
+	checker := d.peerConn
+	d.mu.RUnlock()
+	if checker == nil {
+		return records
+	}
+
+	kept := make([]dns.RR, 0, len(records))
+	var dropped int
+	for _, rr := range records {
+		ip := extractRecordIP(rr)
+		if ip == "" {
+			kept = append(kept, rr)
+			continue
+		}
+		known, connected := checker.IsConnectedByIP(ip)
+		if known && !connected {
+			dropped++
+			continue
+		}
+		kept = append(kept, rr)
+	}
+	if dropped == 0 {
+		return records
+	}
+	if len(kept) == 0 {
+		logger.Debugf("all %d answers for %s point at disconnected peers; returning the original list", dropped, question.Name)
+		return records
+	}
+	logger.Tracef("dropped %d disconnected-peer answer(s) for %s, returning %d", dropped, question.Name, len(kept))
+	return kept
+}
+
+// extractRecordIP returns the dotted-decimal / colon-hex IP carried by
+// an A or AAAA record, or "" for any other record type.
+func extractRecordIP(rr dns.RR) string {
+	switch r := rr.(type) {
+	case *dns.A:
+		if r.A == nil {
+			return ""
+		}
+		return r.A.String()
+	case *dns.AAAA:
+		if r.AAAA == nil {
+			return ""
+		}
+		return r.AAAA.String()
+	}
+	return ""
+}
+
 // Update replaces all zones and their records
 func (d *Resolver) Update(customZones []nbdns.CustomZone) {
 	d.mu.Lock()

client/internal/dns/local/local_test.go

@@ -30,6 +30,21 @@ func (m *mockResolver) LookupNetIP(ctx context.Context, network, host string) ([
 	return nil, nil
 }
 
+// mockPeerConnectivity returns canned (known, connected) results per IP.
+// Used by the disconnected-peer filter tests below. IPs not in the map
+// are reported as unknown so the filter leaves them alone.
+type mockPeerConnectivity struct {
+	byIP map[string]struct{ known, connected bool }
+}
+
+func (m mockPeerConnectivity) IsConnectedByIP(ip string) (known, connected bool) {
+	v, ok := m.byIP[ip]
+	if !ok {
+		return false, false
+	}
+	return v.known, v.connected
+}
+
 func TestLocalResolver_ServeDNS(t *testing.T) {
 	recordA := nbdns.SimpleRecord{
 		Name:  "peera.netbird.cloud.",
@@ -2652,3 +2667,114 @@ func BenchmarkIsInManagedZone_ManyZones(b *testing.B) {
 		resolver.isInManagedZone(qname)
 	}
 }
+
+// TestLocalResolver_FilterDisconnectedPeerAnswers verifies the
+// connectivity-aware filtering layered on top of lookupRecords:
+// when an A record's IP belongs to a known peer that's disconnected,
+// the record is dropped from the answer. Records for unknown IPs pass
+// through. If filtering would empty the answer entirely and at least
+// one record was dropped, the original list is restored (escape hatch
+// for the "all proxies offline" case).
+func TestLocalResolver_FilterDisconnectedPeerAnswers(t *testing.T) {
+	zone := "svc.cluster.netbird."
+	connectedRec := nbdns.SimpleRecord{
+		Name:  zone,
+		Type:  int(dns.TypeA),
+		Class: nbdns.DefaultClass,
+		TTL:   5,
+		RData: "100.64.0.10",
+	}
+	disconnectedRec := nbdns.SimpleRecord{
+		Name:  zone,
+		Type:  int(dns.TypeA),
+		Class: nbdns.DefaultClass,
+		TTL:   5,
+		RData: "100.64.0.11",
+	}
+	unknownRec := nbdns.SimpleRecord{
+		Name:  zone,
+		Type:  int(dns.TypeA),
+		Class: nbdns.DefaultClass,
+		TTL:   5,
+		RData: "203.0.113.5",
+	}
+
+	type ipState struct{ known, connected bool }
+	tests := []struct {
+		name        string
+		records     []nbdns.SimpleRecord
+		connByIP    map[string]ipState
+		wantInOrder []string
+	}{
+		{
+			name:    "drops disconnected peer, keeps connected",
+			records: []nbdns.SimpleRecord{connectedRec, disconnectedRec},
+			connByIP: map[string]ipState{
+				"100.64.0.10": {known: true, connected: true},
+				"100.64.0.11": {known: true, connected: false},
+			},
+			wantInOrder: []string{"100.64.0.10"},
+		},
+		{
+			name:    "unknown IPs pass through untouched",
+			records: []nbdns.SimpleRecord{unknownRec, disconnectedRec},
+			connByIP: map[string]ipState{
+				"100.64.0.11": {known: true, connected: false},
+			},
+			wantInOrder: []string{"203.0.113.5"},
+		},
+		{
+			name:    "all disconnected falls back to original list",
+			records: []nbdns.SimpleRecord{disconnectedRec, connectedRec},
+			connByIP: map[string]ipState{
+				"100.64.0.10": {known: true, connected: false},
+				"100.64.0.11": {known: true, connected: false},
+			},
+			wantInOrder: []string{"100.64.0.11", "100.64.0.10"},
+		},
+		{
+			name:        "no checker wired returns all records",
+			records:     []nbdns.SimpleRecord{connectedRec, disconnectedRec},
+			connByIP:    nil,
+			wantInOrder: []string{"100.64.0.10", "100.64.0.11"},
+		},
+	}
+
+	for _, tc := range tests {
+		t.Run(tc.name, func(t *testing.T) {
+			resolver := NewResolver()
+			if tc.connByIP != nil {
+				cm := mockPeerConnectivity{byIP: make(map[string]struct{ known, connected bool }, len(tc.connByIP))}
+				for ip, st := range tc.connByIP {
+					cm.byIP[ip] = struct{ known, connected bool }{st.known, st.connected}
+				}
+				resolver.SetPeerConnectivity(cm)
+			}
+			resolver.Update([]nbdns.CustomZone{{
+				Domain:           strings.TrimSuffix(zone, "."),
+				Records:          tc.records,
+				NonAuthoritative: true,
+			}})
+
+			var got *dns.Msg
+			writer := &test.MockResponseWriter{
+				WriteMsgFunc: func(m *dns.Msg) error {
+					got = m
+					return nil
+				},
+			}
+			req := new(dns.Msg).SetQuestion(zone, dns.TypeA)
+			resolver.ServeDNS(writer, req)
+
+			require.NotNil(t, got, "resolver must produce a response")
+			require.Len(t, got.Answer, len(tc.wantInOrder),
+				"answer count must match expected: %v", tc.wantInOrder)
+			for i, want := range tc.wantInOrder {
+				a, ok := got.Answer[i].(*dns.A)
+				require.True(t, ok, "answer[%d] must be an A record", i)
+				assert.Equal(t, want, a.A.String(),
+					"answer[%d] expected %s got %s", i, want, a.A.String())
+			}
+		})
+	}
+}

client/internal/dns/mock_server.go

@@ -9,6 +9,7 @@ import (
 
 	dnsconfig "github.com/netbirdio/netbird/client/internal/dns/config"
 	nbdns "github.com/netbirdio/netbird/dns"
+	"github.com/netbirdio/netbird/route"
 	"github.com/netbirdio/netbird/shared/management/domain"
 )
 
@@ -70,10 +71,6 @@ func (m *MockServer) SearchDomains() []string {
 	return make([]string, 0)
 }
 
-// ProbeAvailability mocks implementation of ProbeAvailability from the Server interface
-func (m *MockServer) ProbeAvailability() {
-}
-
 func (m *MockServer) UpdateServerConfig(domains dnsconfig.ServerDomains) error {
 	if m.UpdateServerConfigFunc != nil {
 		return m.UpdateServerConfigFunc(domains)
@@ -85,8 +82,8 @@ func (m *MockServer) PopulateManagementDomain(mgmtURL *url.URL) error {
 	return nil
 }
 
-// SetRouteChecker mock implementation of SetRouteChecker from Server interface
-func (m *MockServer) SetRouteChecker(func(netip.Addr) bool) {
+// SetRouteSources mock implementation of SetRouteSources from Server interface
+func (m *MockServer) SetRouteSources(selected, active func() route.HAMap) {
 	// Mock implementation - no-op
 }
 

client/internal/dns/network_manager_unix.go

@@ -8,6 +8,7 @@ import (
 	"errors"
 	"fmt"
 	"net/netip"
+	"slices"
 	"strings"
 	"time"
 
@@ -32,6 +33,15 @@ const (
 	networkManagerDbusDeviceGetAppliedConnectionMethod                              = networkManagerDbusDeviceInterface + ".GetAppliedConnection"
 	networkManagerDbusDeviceReapplyMethod                                           = networkManagerDbusDeviceInterface + ".Reapply"
 	networkManagerDbusDeviceDeleteMethod                                            = networkManagerDbusDeviceInterface + ".Delete"
+	networkManagerDbusDeviceIp4ConfigProperty                                       = networkManagerDbusDeviceInterface + ".Ip4Config"
+	networkManagerDbusDeviceIp6ConfigProperty                                       = networkManagerDbusDeviceInterface + ".Ip6Config"
+	networkManagerDbusDeviceIfaceProperty                                           = networkManagerDbusDeviceInterface + ".Interface"
+	networkManagerDbusGetDevicesMethod                                              = networkManagerDest + ".GetDevices"
+	networkManagerDbusIp4ConfigInterface                                            = "org.freedesktop.NetworkManager.IP4Config"
+	networkManagerDbusIp6ConfigInterface                                            = "org.freedesktop.NetworkManager.IP6Config"
+	networkManagerDbusIp4ConfigNameserverDataProperty                               = networkManagerDbusIp4ConfigInterface + ".NameserverData"
+	networkManagerDbusIp4ConfigNameserversProperty                                  = networkManagerDbusIp4ConfigInterface + ".Nameservers"
+	networkManagerDbusIp6ConfigNameserversProperty                                  = networkManagerDbusIp6ConfigInterface + ".Nameservers"
 	networkManagerDbusDefaultBehaviorFlag              networkManagerConfigBehavior = 0
 	networkManagerDbusIPv4Key                                                       = "ipv4"
 	networkManagerDbusIPv6Key                                                       = "ipv6"
@@ -51,9 +61,10 @@ var supportedNetworkManagerVersionConstraints = []string{
 }
 
 type networkManagerDbusConfigurator struct {
-	dbusLinkObject dbus.ObjectPath
-	routingAll     bool
-	ifaceName      string
+	dbusLinkObject  dbus.ObjectPath
+	routingAll      bool
+	ifaceName       string
+	origNameservers []netip.Addr
 }
 
 // the types below are based on dbus specification, each field is mapped to a dbus type
@@ -92,10 +103,200 @@ func newNetworkManagerDbusConfigurator(wgInterface string) (*networkManagerDbusC
 
 	log.Debugf("got network manager dbus Link Object: %s from net interface %s", s, wgInterface)
 
-	return &networkManagerDbusConfigurator{
+	c := &networkManagerDbusConfigurator{
 		dbusLinkObject: dbus.ObjectPath(s),
 		ifaceName:      wgInterface,
-	}, nil
+	}
+
+	origNameservers, err := c.captureOriginalNameservers()
+	switch {
+	case err != nil:
+		log.Warnf("capture original nameservers from NetworkManager: %v", err)
+	case len(origNameservers) == 0:
+		log.Warnf("no original nameservers captured from non-WG NetworkManager devices; DNS fallback will be empty")
+	default:
+		log.Debugf("captured %d original nameservers from non-WG NetworkManager devices: %v", len(origNameservers), origNameservers)
+	}
+	c.origNameservers = origNameservers
+	return c, nil
+}
+
+// captureOriginalNameservers reads DNS servers from every NM device's
+// IP4Config / IP6Config except our WG device.
+func (n *networkManagerDbusConfigurator) captureOriginalNameservers() ([]netip.Addr, error) {
+	devices, err := networkManagerListDevices()
+	if err != nil {
+		return nil, fmt.Errorf("list devices: %w", err)
+	}
+
+	seen := make(map[netip.Addr]struct{})
+	var out []netip.Addr
+	for _, dev := range devices {
+		if dev == n.dbusLinkObject {
+			continue
+		}
+		ifaceName := readNetworkManagerDeviceInterface(dev)
+		for _, addr := range readNetworkManagerDeviceDNS(dev) {
+			addr = addr.Unmap()
+			if !addr.IsValid() || addr.IsUnspecified() {
+				continue
+			}
+			// IP6Config.Nameservers is a byte slice without zone info;
+			// reattach the device's interface name so a captured fe80::…
+			// stays routable.
+			if addr.IsLinkLocalUnicast() && ifaceName != "" {
+				addr = addr.WithZone(ifaceName)
+			}
+			if _, dup := seen[addr]; dup {
+				continue
+			}
+			seen[addr] = struct{}{}
+			out = append(out, addr)
+		}
+	}
+	return out, nil
+}
+
+func readNetworkManagerDeviceInterface(devicePath dbus.ObjectPath) string {
+	obj, closeConn, err := getDbusObject(networkManagerDest, devicePath)
+	if err != nil {
+		return ""
+	}
+	defer closeConn()
+	v, err := obj.GetProperty(networkManagerDbusDeviceIfaceProperty)
+	if err != nil {
+		return ""
+	}
+	s, _ := v.Value().(string)
+	return s
+}
+
+func networkManagerListDevices() ([]dbus.ObjectPath, error) {
+	obj, closeConn, err := getDbusObject(networkManagerDest, networkManagerDbusObjectNode)
+	if err != nil {
+		return nil, fmt.Errorf("dbus NetworkManager: %w", err)
+	}
+	defer closeConn()
+	var devs []dbus.ObjectPath
+	if err := obj.Call(networkManagerDbusGetDevicesMethod, dbusDefaultFlag).Store(&devs); err != nil {
+		return nil, err
+	}
+	return devs, nil
+}
+
+func readNetworkManagerDeviceDNS(devicePath dbus.ObjectPath) []netip.Addr {
+	obj, closeConn, err := getDbusObject(networkManagerDest, devicePath)
+	if err != nil {
+		return nil
+	}
+	defer closeConn()
+
+	var out []netip.Addr
+	if path := readNetworkManagerConfigPath(obj, networkManagerDbusDeviceIp4ConfigProperty); path != "" {
+		out = append(out, readIPv4ConfigDNS(path)...)
+	}
+	if path := readNetworkManagerConfigPath(obj, networkManagerDbusDeviceIp6ConfigProperty); path != "" {
+		out = append(out, readIPv6ConfigDNS(path)...)
+	}
+	return out
+}
+
+func readNetworkManagerConfigPath(obj dbus.BusObject, property string) dbus.ObjectPath {
+	v, err := obj.GetProperty(property)
+	if err != nil {
+		return ""
+	}
+	path, ok := v.Value().(dbus.ObjectPath)
+	if !ok || path == "/" {
+		return ""
+	}
+	return path
+}
+
+func readIPv4ConfigDNS(path dbus.ObjectPath) []netip.Addr {
+	obj, closeConn, err := getDbusObject(networkManagerDest, path)
+	if err != nil {
+		return nil
+	}
+	defer closeConn()
+
+	// NameserverData (NM 1.13+) carries strings; older NMs only expose the
+	// legacy uint32 Nameservers property.
+	if out := readIPv4NameserverData(obj); len(out) > 0 {
+		return out
+	}
+	return readIPv4LegacyNameservers(obj)
+}
+
+func readIPv4NameserverData(obj dbus.BusObject) []netip.Addr {
+	v, err := obj.GetProperty(networkManagerDbusIp4ConfigNameserverDataProperty)
+	if err != nil {
+		return nil
+	}
+	entries, ok := v.Value().([]map[string]dbus.Variant)
+	if !ok {
+		return nil
+	}
+	var out []netip.Addr
+	for _, entry := range entries {
+		addrVar, ok := entry["address"]
+		if !ok {
+			continue
+		}
+		s, ok := addrVar.Value().(string)
+		if !ok {
+			continue
+		}
+		if a, err := netip.ParseAddr(s); err == nil {
+			out = append(out, a)
+		}
+	}
+	return out
+}
+
+func readIPv4LegacyNameservers(obj dbus.BusObject) []netip.Addr {
+	v, err := obj.GetProperty(networkManagerDbusIp4ConfigNameserversProperty)
+	if err != nil {
+		return nil
+	}
+	raw, ok := v.Value().([]uint32)
+	if !ok {
+		return nil
+	}
+	out := make([]netip.Addr, 0, len(raw))
+	for _, n := range raw {
+		var b [4]byte
+		binary.LittleEndian.PutUint32(b[:], n)
+		out = append(out, netip.AddrFrom4(b))
+	}
+	return out
+}
+
+func readIPv6ConfigDNS(path dbus.ObjectPath) []netip.Addr {
+	obj, closeConn, err := getDbusObject(networkManagerDest, path)
+	if err != nil {
+		return nil
+	}
+	defer closeConn()
+	v, err := obj.GetProperty(networkManagerDbusIp6ConfigNameserversProperty)
+	if err != nil {
+		return nil
+	}
+	raw, ok := v.Value().([][]byte)
+	if !ok {
+		return nil
+	}
+	out := make([]netip.Addr, 0, len(raw))
+	for _, b := range raw {
+		if a, ok := netip.AddrFromSlice(b); ok {
+			out = append(out, a)
+		}
+	}
+	return out
+}
+
+func (n *networkManagerDbusConfigurator) getOriginalNameservers() []netip.Addr {
+	return slices.Clone(n.origNameservers)
 }
 
 func (n *networkManagerDbusConfigurator) supportCustomPort() bool {