[management, client, proxy] Follow-up fixes for private reverse-proxy services (#6268)

* fix(proxy): gate tunnel-peer fast-path on inbound listener marker

forwardWithTunnelPeer previously accepted any RFC1918 / ULA / CGNAT
source IP, so a public client whose address happened to fall in those
ranges could bypass the configured operator auth scheme by colliding
with a known tunnel IP. The fast-path is now gated on
TunnelLookupFromContext(r.Context()) being present — that context value
is attached only by the per-account inbound (overlay) listener, so the
host-facing listener never enters this branch.

Tests updated to reflect the new requirement: requests that don't
carry the inbound marker now fall through to the regular auth flow.

* fix(proxy): harden inbound listener resource + startup-ctx handling

Three correctness fixes on the per-account inbound path, with tests:

- Close the logrus ErrorLog PipeWriter on tearDown. WriterLevel hands
  back an *io.PipeWriter backed by a pipe + scanner goroutine that the
  caller owns; the two writers per account (https + plain) were never
  closed, leaking the pipe and goroutine on every teardown.
- Run the post-Start hooks on context.Background(). runClientStartup
  is launched in a goroutine from AddPeer and was inheriting the
  caller's request-scoped ctx, so a cancelled request could abort the
  inbound bring-up or fail the management status notification. The
  tail is split into notifyClientReady so the contract is testable.

Tests cover the PipeWriter close behaviour and assert the readyHandler
+ NotifyStatus calls receive a non-cancelled background context.

* feat(proxy): short-circuit peer-own-target loops with 421

When a peer that hosts the target of a private service dials its own
service URL the request was being looped through the proxy and back
over WireGuard to the same peer — twice the WG round-trip for no
benefit, with no signal to the caller that something was wrong.

Add isSelfTargetLoop to ReverseProxy.ServeHTTP: when the request
arrived on the per-account overlay listener (IsOverlayOrigin) and the
source tunnel IP matches the target host, refuse the request with 421
Misdirected Request and a body pointing the operator at the backend
directly.

The gate is scoped to overlay origin so requests on the public
listener that happen to share a source IP with the target host are
forwarded normally.

* fix(management): private-service validation + tunnel-IP lookup semantics

- Require an explicit port for L4 cluster targets. validateL4Target
  exempted TargetTypeCluster from the port check, but buildPathMappings
  serializes every L4 target via net.JoinHostPort(host, port) — port=0
  shipped a ":0" upstream. Cluster targets use the same Host/Port
  fields, so the same requirement applies.
- GetPeerByIP returns NotFound on a tunnel-IP miss instead of mapping
  every error to Internal. The proxy's ValidateTunnelPeer probes IPs
  that legitimately aren't in the roster; the miss is expected and now
  distinguishable from a real store failure.
- Thread ctx into getClusterCapability's gorm query so a cancelled
  request doesn't keep the store busy.

Tests updated for the L4-cluster port requirement and the GetPeerByIP
NotFound path.

* fix(client): include offlinePeers in PeerStateByIP lookup

ReplaceOfflinePeers moves peers into d.offlinePeers but PeerStateByIP
only scanned d.peers. Callers (the local DNS filter via
localPeerConnectivity, embed.Client.IdentityForIP used by the
proxy's tunnel-peer validator) were treating known-but-offline peers
as unknown, which:

- causes the DNS filter to keep returning records pointing at peers
  that have no live tunnel, AND
- makes the proxy's local-roster check deny a request from such a
  peer rather than letting the cached management RPC carry the
  authorisation decision.

Search both slices in PeerStateByIP. Adds a unit test for the IPv4
and IPv6 offline-match paths.

* fix(rest): reject empty Delete path params in reverse-proxy clients

ReverseProxyClustersAPI.Delete and ReverseProxyTokensAPI.Delete passed
the path parameter into url.PathEscape without an empty check.
PathEscape("") returns "" which collapses the request onto the
collection endpoint ("/api/reverse-proxies/clusters/" /
"/api/reverse-proxies/proxy-tokens/"), so a caller bug delete with no
id reached a routable URL with surprising semantics (typically 405).

Short-circuit with a typed error before the request is built. Tests
mount a handler on the collection path that fails the test if hit, so
the regression is impossible to reintroduce silently.

* chore(api,ci,docs,test): private-service schema, proto-check, fixups

Non-functional cleanups and contract/CI hardening around the
private-service work:

API schema (openapi.yml):
- Require a non-empty access_groups and mode=http when private=true,
  on both Service and ServiceRequest, mirroring
  validatePrivateRequirements. mode stays optional-but-constrained
  (empty defaults to http server-side), matching runtime.

CI (proto-version-check.yml):
- Cover renamed .pb.go files (read base via previous_filename).
- Match protoc-gen-go-grpc version headers (optional "- " prefix and
  -gen-go-grpc suffix) so grpc-generated files are in scope.

Docs / comments:
- Reword Config field docs to say defaults are applied at Server.Start
  (initDefaults), not New.
- Rename the obsolete --private-inbound flag to --private across
  comments and the proto doc.

Pre-existing test fixups surfaced by review:
- Repair the integration-tagged validate_session_test.go (SignToken
  signature growth + new Manager interface methods).
- Fix the CI-skip boolean precedence so Windows isn't skipped
  unconditionally.
- Guard the router.HTTPListener type assertion with comma-ok.

* fix(proxy): background ctx for already-started AddPeer notification

The earlier ctx fix covered the async runClientStartup path but missed
the synchronous branch: when a service is added to an already-started
client, AddPeer called NotifyStatus with the caller's request-scoped
ctx. A cancelled request/stream could drop the connected notification
to management. Use context.Background() here too, matching
notifyClientReady.

Extends TestNetBird_AddPeer_ExistingStartedClient_NotifiesStatus to
pass a pre-cancelled caller ctx and assert the notification still ran
on a non-cancelled context.

* use the cmd context for roundtripper

shared/management/client/rest/reverse_proxy_clusters.go

@@ -2,6 +2,7 @@ package rest
 
 import (
 	"context"
+	"errors"
 	"net/url"
 
 	"github.com/netbirdio/netbird/shared/management/http/api"
@@ -33,6 +34,12 @@ func (a *ReverseProxyClustersAPI) List(ctx context.Context) ([]api.ProxyCluster,
 // NetBird cannot be deleted via this endpoint; the server returns 404 / 400
 // for cluster addresses the account does not own.
 func (a *ReverseProxyClustersAPI) Delete(ctx context.Context, clusterAddress string) error {
+	// Guard against the empty input: url.PathEscape("") returns "" which
+	// would collapse the request URL onto the collection endpoint and
+	// silently delete nothing (or 405 depending on routing).
+	if clusterAddress == "" {
+		return errors.New("clusterAddress is required")
+	}
 	resp, err := a.c.NewRequest(ctx, "DELETE", "/api/reverse-proxies/clusters/"+url.PathEscape(clusterAddress), nil, nil)
 	if err != nil {
 		return err

shared/management/client/rest/reverse_proxy_clusters_test.go

@@ -88,3 +88,17 @@ func TestReverseProxyClusters_Delete_Err(t *testing.T) {
 		assert.Error(t, err)
 	})
 }
+
+// TestReverseProxyClusters_Delete_EmptyAddress guards against an empty
+// clusterAddress reaching the wire — that would collapse the URL onto
+// the collection endpoint instead of a specific cluster. The client
+// must short-circuit with a typed error before any request is issued.
+func TestReverseProxyClusters_Delete_EmptyAddress(t *testing.T) {
+	withMockClient(func(c *rest.Client, mux *http.ServeMux) {
+		mux.HandleFunc("/api/reverse-proxies/clusters/", func(http.ResponseWriter, *http.Request) {
+			t.Fatal("empty clusterAddress must be rejected client-side; no request should reach the server")
+		})
+		err := c.ReverseProxyClusters.Delete(context.Background(), "")
+		assert.Error(t, err, "empty clusterAddress must surface as an error")
+	})
+}

shared/management/client/rest/reverse_proxy_tokens.go

@@ -4,6 +4,7 @@ import (
 	"bytes"
 	"context"
 	"encoding/json"
+	"errors"
 	"net/url"
 
 	"github.com/netbirdio/netbird/shared/management/http/api"
@@ -61,6 +62,12 @@ func (a *ReverseProxyTokensAPI) Create(ctx context.Context, request api.ProxyTok
 // credentials existed; the plain secret can no longer authenticate any
 // new proxy registration.
 func (a *ReverseProxyTokensAPI) Delete(ctx context.Context, tokenID string) error {
+	// Guard against the empty input: url.PathEscape("") returns "" which
+	// would collapse the request URL onto the collection endpoint and
+	// silently delete nothing (or 405 depending on routing).
+	if tokenID == "" {
+		return errors.New("tokenID is required")
+	}
 	resp, err := a.c.NewRequest(ctx, "DELETE", "/api/reverse-proxies/proxy-tokens/"+url.PathEscape(tokenID), nil, nil)
 	if err != nil {
 		return err

shared/management/client/rest/reverse_proxy_tokens_test.go

@@ -129,3 +129,16 @@ func TestReverseProxyTokens_Delete_Err(t *testing.T) {
 		assert.Error(t, err)
 	})
 }
+
+// TestReverseProxyTokens_Delete_EmptyID guards against an empty tokenID
+// reaching the wire — url.PathEscape("") would collapse the URL onto
+// the collection endpoint.
+func TestReverseProxyTokens_Delete_EmptyID(t *testing.T) {
+	withMockClient(func(c *rest.Client, mux *http.ServeMux) {
+		mux.HandleFunc("/api/reverse-proxies/proxy-tokens/", func(http.ResponseWriter, *http.Request) {
+			t.Fatal("empty tokenID must be rejected client-side; no request should reach the server")
+		})
+		err := c.ReverseProxyTokens.Delete(context.Background(), "")
+		assert.Error(t, err, "empty tokenID must surface as an error")
+	})
+}

shared/management/http/api/openapi.yml

@@ -3086,6 +3086,24 @@ components:
         - enabled
         - auth
         - meta
+      allOf:
+        # When private=true, access_groups must be present and non-empty,
+        # and the service mode must be "http". The bearer-auth mutex is
+        # enforced at the service-validation layer
+        # (validatePrivateRequirements) because it sits in a nested
+        # ServiceAuthConfig and isn't cleanly expressible here.
+        - if:
+            required: [private]
+            properties:
+              private:
+                const: true
+          then:
+            required: [access_groups]
+            properties:
+              access_groups:
+                minItems: 1
+              mode:
+                const: http
     ServiceMeta:
       type: object
       properties:
@@ -3173,6 +3191,23 @@ components:
         - name
         - domain
         - enabled
+      allOf:
+        # Mirror of the Service conditional: when private=true the
+        # request must carry a non-empty access_groups list and the
+        # mode must be "http". The bearer-auth mutex is enforced at the
+        # service-validation layer (validatePrivateRequirements).
+        - if:
+            required: [private]
+            properties:
+              private:
+                const: true
+          then:
+            required: [access_groups]
+            properties:
+              access_groups:
+                minItems: 1
+              mode:
+                const: http
     ServiceTargetOptions:
       type: object
       properties:

shared/management/proto/proxy_service.proto

@@ -237,7 +237,7 @@ message SendStatusUpdateRequest {
   bool certificate_issued = 4;
   optional string error_message = 5;
   // Per-account inbound listener state for the account that owns
-  // service_id. Populated only when --private-inbound is enabled and the
+  // service_id. Populated only when --private is enabled and the
   // embedded client for the account is up. Field numbers >=50 reserved
   // for observability extensions.
   optional ProxyInboundListener inbound_listener = 50;