Merge remote-tracking branch 'origin/main' into merge-ssh-settings-elevation

* Fix staticcheck findings reported by the updated golangci-lint

* Skip the receive error log when the local context is done

.goreleaser_ui.yaml

@@ -92,6 +92,11 @@ nfpms:
         dst: /usr/share/applications/org.wails.netbird.desktop
       - src: client/ui/build/appicon.png
         dst: /usr/share/pixmaps/netbird.png
+      # Names the polkit action for the elevation prompt the app raises when an
+      # unprivileged user changes a privileged setting; without it the dialog
+      # shows a raw command line.
+      - src: client/ui/build/linux/polkit/io.netbird.settings.policy
+        dst: /usr/share/polkit-1/actions/io.netbird.settings.policy
     dependencies:
       - netbird (>= 0.75.0)
       - libgtk-4-1 (>= 4.14)
@@ -116,6 +121,11 @@ nfpms:
         dst: /usr/share/applications/org.wails.netbird.desktop
       - src: client/ui/build/appicon.png
         dst: /usr/share/pixmaps/netbird.png
+      # Names the polkit action for the elevation prompt the app raises when an
+      # unprivileged user changes a privileged setting; without it the dialog
+      # shows a raw command line.
+      - src: client/ui/build/linux/polkit/io.netbird.settings.policy
+        dst: /usr/share/polkit-1/actions/io.netbird.settings.policy
     dependencies:
       - netbird >= 0.75.0
       - (gtk4 >= 4.14 or libgtk-4-1 >= 4.14)

AGENTS.md

@@ -1,6 +1,6 @@
 # NetBird Agent Guidelines
 
-**NetBird** is an open-source connectivity platform: a WireGuard®-based overlay
+**NetBird** is an open source connectivity platform: a WireGuard®-based overlay
 network with a control plane. The **agent** (`client/`) runs on user machines as
 a privileged daemon and manages the WireGuard interface, routing, firewall, and
 DNS. **Management** (`management/`) is the control plane and REST/gRPC API,

CONTRIBUTING.md

@@ -479,7 +479,7 @@ go test -race ./client/internal/dns/...
 
 ## Checklist before submitting a PR
 
-As a critical network service and open-source project, we must enforce a few
+As a critical network service and open source project, we must enforce a few
 things before submitting a pull request. The
 [pull request template](/.github/pull_request_template.md) mirrors this list —
 fill it in rather than deleting it.

README.md

@@ -130,7 +130,7 @@ In November 2022, NetBird joined the [StartUpSecure program](https://www.forschu
 ![CISPA_Logo_BLACK_EN_RZ_RGB (1)](https://user-images.githubusercontent.com/700848/203091324-c6d311a0-22b5-4b05-a288-91cbc6cdcc46.png)
 
 ### 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).
+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 the BSD-3-Clause license, which applies to all parts of the repository except for the directories management/, signal/ and relay/.

SECURITY.md

@@ -14,7 +14,7 @@ Report security issues one of these two ways:
   on this repository. This is the preferred route: it keeps the discussion, the draft advisory, and the credit in one place.
 - **Email** — `security@netbird.io`.
 
-If the finding affects NetBird Cloud or our hosted infrastructure rather than the open-source code, email us rather than
+If the finding affects NetBird Cloud or our hosted infrastructure rather than the open source code, email us rather than
 filing a repository report.
 
 ### What to include

agent-network/README.md

@@ -40,35 +40,6 @@ You can then use this private endpoint to configure your AI agents, whether that
 Full step-by-step setup:
 **https://docs.netbird.io/agent-network/quickstart**
 
-## Client settings that don't follow the endpoint
-
-Most of an agent's traffic follows the base URL you hand it, but a few
-client-side checks call their vendor directly and never reach the proxy. On a
-network that blocks direct egress they fail even though inference works, so
-they are worth setting once when you roll the endpoint out.
-
-For Claude Code:
-
-- **Fast mode** checks availability against `api.anthropic.com` rather than the
-  configured base URL. Set `CLAUDE_CODE_SKIP_FAST_MODE_ORG_CHECK=1` when the
-  agent authenticates with `ANTHROPIC_AUTH_TOKEN` alone (the usual shape when
-  the proxy injects the real provider key) or when a TLS-inspecting proxy
-  answers the check itself. Set
-  `CLAUDE_CODE_SKIP_FAST_MODE_NETWORK_ERRORS=1` when the network refuses the
-  connection outright. Fast mode is an Anthropic-API feature, so it is
-  unavailable on a Bedrock- or Vertex-backed endpoint whatever you set.
-- **Model discovery** is off by default. Set
-  `CLAUDE_CODE_ENABLE_GATEWAY_MODEL_DISCOVERY=1` for the picker to list the
-  models your policies authorise; the proxy filters the response to that set.
-  The client gives discovery a three-second budget and treats any redirect as
-  a failure, so the endpoint must serve `/v1/models` directly.
-- **The WebFetch domain safety check** also calls `api.anthropic.com` directly
-  and is unaffected by the variables above.
-
-Allowing direct egress to `api.anthropic.com` covers the network cases but not
-the credential one, where the check reaches Anthropic and is rejected because
-the agent presents a proxy-issued key.
-
 ## Architecture 
 
 Agent Network is built on two existing NetBird capabilities:

client/android/client.go

@@ -26,6 +26,8 @@ import (
 	"github.com/netbirdio/netbird/client/internal/routemanager"
 	"github.com/netbirdio/netbird/client/internal/stdnet"
 	"github.com/netbirdio/netbird/client/net"
+	"github.com/netbirdio/netbird/client/netstate"
+	"github.com/netbirdio/netbird/client/netsweep"
 	"github.com/netbirdio/netbird/client/system"
 	"github.com/netbirdio/netbird/formatter"
 	"github.com/netbirdio/netbird/route"
@@ -40,11 +42,6 @@ const (
 	AnonymizeLevelStrict  = nbAnonymize.LevelStrictString
 )
 
-// ConnectionListener export internal Listener for mobile
-type ConnectionListener interface {
-	peer.Listener
-}
-
 // TunAdapter export internal TunAdapter for mobile
 type TunAdapter interface {
 	device.TunAdapter
@@ -85,6 +82,13 @@ type Client struct {
 	deviceName            string
 	uiVersion             string
 	networkChangeListener listener.NetworkChangeListener
+	// netState outlives engine restarts: it mirrors the OS connectivity, not
+	// the engine lifecycle. Run and RunWithoutLogin inject it into each new
+	// ConnectClient, which distributes it to every reconnection loop.
+	netState *netstate.State
+
+	// sweeper also outlives engine restarts; NotifyNetworkChange sweeps it.
+	sweeper *netsweep.Sweeper
 
 	stateMu       sync.RWMutex
 	connectClient *internal.ConnectClient
@@ -148,6 +152,7 @@ func NewClient(androidSDKVersion int, deviceName string, uiVersion string, tunAd
 	execWorkaround(androidSDKVersion)
 
 	net.SetAndroidProtectSocketFn(tunAdapter.ProtectSocket)
+	system.SetIFaceDiscover(iFaceDiscover)
 	return &Client{
 		deviceName:            deviceName,
 		uiVersion:             uiVersion,
@@ -156,6 +161,8 @@ func NewClient(androidSDKVersion int, deviceName string, uiVersion string, tunAd
 		recorder:              peer.NewRecorder(""),
 		ctxCancelLock:         &sync.Mutex{},
 		networkChangeListener: networkChangeListener,
+		netState:              netstate.New(),
+		sweeper:               netsweep.New(),
 	}
 }
 
@@ -196,7 +203,8 @@ func (c *Client) Run(platformFiles PlatformFiles, urlOpener URLOpener, isAndroid
 	}
 	// todo do not throw error in case of cancelled context
 	ctx = internal.CtxInitState(ctx)
-	connectClient := internal.NewConnectClient(ctx, cfg, c.recorder)
+	connectClient := internal.NewConnectClient(ctx, cfg, c.recorder,
+		internal.WithNetworkState(c.netState), internal.WithSweeper(c.sweeper))
 	c.setState(cfg, cacheDir, cfgFile, connectClient)
 	// This path runs the interactive SSO flow, so reaching here means the peer
 	// is authenticated again — release the latch Status() reports from. Clear
@@ -237,7 +245,8 @@ func (c *Client) RunWithoutLogin(platformFiles PlatformFiles, dns *DNSList, dnsR
 
 	// todo do not throw error in case of cancelled context
 	ctx = internal.CtxInitState(ctx)
-	connectClient := internal.NewConnectClient(ctx, cfg, c.recorder)
+	connectClient := internal.NewConnectClient(ctx, cfg, c.recorder,
+		internal.WithNetworkState(c.netState), internal.WithSweeper(c.sweeper))
 	c.setState(cfg, cacheDir, cfgFile, connectClient)
 	return connectClient.RunOnAndroid(c.tunAdapter, c.iFaceDiscover, c.networkChangeListener, slices.Clone(dns.items), dnsReadyListener, stateFile, cacheDir)
 }
@@ -285,6 +294,24 @@ func (c *Client) GetTunSettings() (*TunSettings, error) {
 	}, nil
 }
 
+// SetNetworkAvailable feeds OS-reported network availability into the client.
+// While unavailable, the internal reconnect loops suspend their attempts and
+// the connection listener reports NoNetwork instead of Connecting; when
+// availability returns, the loops resume immediately with a fresh backoff.
+func (c *Client) SetNetworkAvailable(available bool) {
+	c.netState.Set(available)
+	c.recorder.SetNetworkAvailable(available)
+}
+
+// NotifyNetworkChange marks the management, signal and relay connections
+// stale after the OS switched networks and schedules a sweep that cuts
+// whatever has not redialed on the new network by then. The engine and the
+// TUN device stay untouched.
+func (c *Client) NotifyNetworkChange() {
+	c.sweeper.MarkNetworkChange()
+	log.Infof("network change: connections marked stale")
+}
+
 // DebugBundle generates a debug bundle, uploads it, and returns the upload key.
 // It works both with and without a running engine. anonymizeLevel is "default"
 // or "strict"; strict also anonymizes internal IP ranges, peer names, and
@@ -525,7 +552,11 @@ func (c *Client) OnUpdatedHostDNS(list *DNSList) error {
 
 // SetConnectionListener set the network connection listener
 func (c *Client) SetConnectionListener(listener ConnectionListener) {
-	c.recorder.SetConnectionListener(listener)
+	if listener == nil {
+		c.recorder.RemoveConnectionListener()
+		return
+	}
+	c.recorder.SetConnectionListener(connectionListenerAdapter{listener})
 }
 
 // RemoveConnectionListener remove connection listener

client/android/connection_listener.go

@@ -0,0 +1,41 @@
+//go:build android
+
+package android
+
+import (
+	"github.com/netbirdio/netbird/client/internal/peer"
+)
+
+// Client state values delivered via ConnectionListener.OnStateChanged,
+// re-exported as basic constants so gomobile emits them into the generated
+// Java bindings. They mirror peer.ClientState*: append-only, never reorder.
+const (
+	ClientStateDisconnected  = int(peer.ClientStateDisconnected)
+	ClientStateConnected     = int(peer.ClientStateConnected)
+	ClientStateConnecting    = int(peer.ClientStateConnecting)
+	ClientStateDisconnecting = int(peer.ClientStateDisconnecting)
+	ClientStateNoNetwork     = int(peer.ClientStateNoNetwork)
+)
+
+// ConnectionListener export internal Listener for mobile. It mirrors
+// peer.Listener with OnStateChanged taking a plain int (one of the
+// ClientState* constants), because gomobile cannot bind named types.
+type ConnectionListener interface {
+	OnStateChanged(state int)
+	OnConnected()
+	OnDisconnected()
+	OnConnecting()
+	OnDisconnecting()
+	OnAddressChanged(string, string)
+	OnPeersListChanged(int)
+}
+
+// connectionListenerAdapter adapts the gomobile-facing ConnectionListener to
+// peer.Listener, converting the typed state to the int the binding carries.
+type connectionListenerAdapter struct {
+	ConnectionListener
+}
+
+func (a connectionListenerAdapter) OnStateChanged(state peer.ClientState) {
+	a.ConnectionListener.OnStateChanged(int(state))
+}

client/android/login.go

@@ -191,40 +191,49 @@ func (a *Auth) login(urlOpener URLOpener, isAndroidTV bool) error {
 	return nil
 }
 
-// loginHintSetter is implemented by both concrete flows (PKCE and device code)
-// but absent from the OAuthFlow interface, hence the assertion below — the same
-// way internal/auth wires it in authenticateWithPKCEFlow.
-type loginHintSetter interface {
-	SetLoginHint(hint string)
-}
-
 func (a *Auth) foregroundGetTokenInfo(authClient *auth.Auth, urlOpener URLOpener, isAndroidTV bool) (*auth.TokenInfo, error) {
-	oAuthFlow, err := authClient.GetOAuthFlow(a.ctx, isAndroidTV)
+	oAuthFlow, err := authClient.GetOAuthFlow(a.ctx, isAndroidTV, profileLoginHint(a.cfgPath))
 	if err != nil {
 		return nil, fmt.Errorf("failed to get OAuth flow: %v", err)
 	}
 
-	// An empty hint is deliberate, not a fallback: a fresh profile leaves the
-	// choice to the IdP. Switching accounts is done by switching or removing
-	// profiles, not by logging out — logout keeps the email.
-	if a.cfgPath != "" {
-		if hint := readProfileEmail(a.cfgPath); hint != "" {
-			if setter, ok := oAuthFlow.(loginHintSetter); ok {
-				setter.SetLoginHint(hint)
-			}
-		}
+	return runOAuthFlow(a.ctx, oAuthFlow, urlOpener, nil)
+}
+
+// profileLoginHint returns the stored account email for the profile at cfgPath.
+// An empty hint is deliberate, not a fallback: a fresh profile leaves the
+// choice to the IdP. Switching accounts is done by switching or removing
+// profiles, not by logging out — logout keeps the email.
+func profileLoginHint(cfgPath string) string {
+	if cfgPath == "" {
+		return ""
+	}
+	return readProfileEmail(cfgPath)
+}
+
+// runOAuthFlow drives an already acquired OAuth flow to a token: requests the
+// flow info, presents the verification URL through the opener and waits for
+// the browser round-trip. Open is called synchronously — it is what marks the
+// surface as opened on the client side, and a fast token's OnLoginSuccess is
+// a no-op until it has, so the dismissal would be dropped rather than
+// delayed. Openers must therefore not block: they post their UI work and
+// return. onWaiting, when set, runs after the URL is shown, right before the
+// blocking wait.
+func runOAuthFlow(ctx context.Context, flow auth.OAuthFlow, urlOpener URLOpener, onWaiting func()) (*auth.TokenInfo, error) {
+	flowInfo, err := flow.RequestAuthInfo(ctx)
+	if err != nil {
+		return nil, fmt.Errorf("request auth info: %w", err)
 	}
 
-	flowInfo, err := oAuthFlow.RequestAuthInfo(context.TODO())
-	if err != nil {
-		return nil, fmt.Errorf("getting a request OAuth flow info failed: %v", err)
+	urlOpener.Open(flowInfo.VerificationURIComplete, flowInfo.UserCode)
+
+	if onWaiting != nil {
+		onWaiting()
 	}
 
-	go urlOpener.Open(flowInfo.VerificationURIComplete, flowInfo.UserCode)
-
-	tokenInfo, err := oAuthFlow.WaitToken(a.ctx, flowInfo)
+	tokenInfo, err := flow.WaitToken(ctx, flowInfo)
 	if err != nil {
-		return nil, fmt.Errorf("waiting for browser login failed: %v", err)
+		return nil, fmt.Errorf("wait for token: %w", err)
 	}
 
 	return &tokenInfo, nil

client/android/profile_prefs.go

@@ -0,0 +1,38 @@
+//go:build android
+
+package android
+
+import (
+	"fmt"
+
+	"github.com/netbirdio/netbird/client/internal/profilemanager"
+)
+
+type prefsStore interface {
+	Get(namespace string, v any) (bool, error)
+	Put(namespace string, v any) error
+}
+
+type profilePrefs struct {
+	prefs *profilemanager.Prefs
+}
+
+func newProfilePrefs(configDir, profileID string) (*profilePrefs, error) {
+	if configDir == "" || profileID == "" {
+		return nil, fmt.Errorf("profile prefs require a config dir and profile ID")
+	}
+	pm := NewProfileManager(configDir)
+	prefs, err := pm.serviceMgr.ProfilePrefs(profilemanager.ID(profileID), androidUsername)
+	if err != nil {
+		return nil, fmt.Errorf("resolve profile prefs: %w", err)
+	}
+	return &profilePrefs{prefs: prefs}, nil
+}
+
+func (p *profilePrefs) Get(namespace string, v any) (bool, error) {
+	return p.prefs.Get(namespace, v)
+}
+
+func (p *profilePrefs) Put(namespace string, v any) error {
+	return p.prefs.Put(namespace, v)
+}

client/android/ssh_client.go

@@ -0,0 +1,649 @@
+//go:build android
+
+package android
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"io"
+	"net"
+	"strconv"
+	"strings"
+	"sync"
+	"time"
+
+	log "github.com/sirupsen/logrus"
+	gossh "golang.org/x/crypto/ssh"
+
+	"github.com/netbirdio/netbird/client/internal"
+	"github.com/netbirdio/netbird/client/internal/auth"
+	"github.com/netbirdio/netbird/client/internal/profilemanager"
+	nbssh "github.com/netbirdio/netbird/client/ssh"
+	"github.com/netbirdio/netbird/client/ssh/detection"
+)
+
+const (
+	sshDialTimeout      = 30 * time.Second
+	sshDetectionTimeout = 5 * time.Second
+)
+
+// PasswordRequiredMarker tells Java to prompt for a password and retry. It is
+// a string because gomobile flattens errors to their message, so a sentinel
+// value would not survive the binding.
+const PasswordRequiredMarker = "netbird-ssh-password-required"
+
+// HostKeyUnknownMarker tells Java to show the fingerprint and, on confirmation,
+// retry with TrustHostKey set. The presented fingerprint is appended after the
+// marker so the prompt can display it and the retry can guard against a key
+// that changed between the two connects. Only regular (non-NetBird) servers
+// reach this: NetBird peers verify against the registry.
+const HostKeyUnknownMarker = "netbird-ssh-hostkey-unknown"
+
+var (
+	errPasswordRequired = errors.New(PasswordRequiredMarker)
+	errClientClosed     = errors.New("ssh client closed")
+)
+
+// errHostKeyUnknown carries the presented fingerprint so Connect can build the
+// marker message the Java side parses.
+type errHostKeyUnknown struct {
+	fingerprint string
+}
+
+func (e *errHostKeyUnknown) Error() string {
+	return HostKeyUnknownMarker + ":" + e.fingerprint
+}
+
+// SSHTerminalListener receives SSH session events. It is implemented in Java.
+//
+// All callbacks are invoked from goroutines and may run concurrently with each
+// other; the implementation must be safe to call from any thread.
+type SSHTerminalListener interface {
+	OnConnected()
+	OnData(data []byte)
+	OnClose(reason string)
+	OnError(message string)
+}
+
+// SSHClient is a NetBird-aware SSH client exposed to Java via gomobile.
+//
+// It dials through the running NetBird tunnel and runs a standard SSH session
+// on top with PTY enabled. Host-key verification uses the NetBird-provided
+// peer SSH host keys, identical to the desktop client.
+type SSHClient struct {
+	nb        *Client
+	mu        sync.Mutex
+	listener  SSHTerminalListener
+	urlOpener URLOpener
+
+	sshClient *gossh.Client
+	session   *gossh.Session
+	stdin     io.WriteCloser
+	closed    bool
+
+	// gen identifies the current connection attempt. Connect and Close bump it,
+	// so an in-flight dial or a reader left over from a previous connection
+	// finds itself stale and stays silent instead of publishing OnConnected or
+	// OnClose for a connection the caller already abandoned.
+	gen        uint64
+	dialCancel context.CancelFunc
+
+	// knownHostsConfigDir and knownHostsProfile locate the TOFU store for
+	// regular SSH servers in the profile's preferences. Java supplies them,
+	// since an overlay IP is a different host under a different profile. Empty
+	// until set: without them a regular server cannot be verified and Connect
+	// refuses one.
+	knownHostsConfigDir string
+	knownHostsProfile   string
+	// trustHostKey carries the fingerprint the user confirmed on a previous
+	// attempt, so the retry accepts exactly that key and persists it.
+	trustHostKey string
+}
+
+// NewSSHClient creates a new SSH client bound to the running NetBird Client.
+func NewSSHClient(c *Client) *SSHClient {
+	return &SSHClient{nb: c}
+}
+
+// SetListener registers the Java listener. Must be called before Connect to
+// receive any events.
+func (s *SSHClient) SetListener(l SSHTerminalListener) {
+	s.mu.Lock()
+	s.listener = l
+	s.mu.Unlock()
+}
+
+// SetURLOpener registers the Java URL opener used to display the device-code
+// authorization page in a Custom Tabs window when the target peer requires
+// JWT authentication. Must be set before Connect to be effective.
+func (s *SSHClient) SetURLOpener(opener URLOpener) {
+	s.mu.Lock()
+	s.urlOpener = opener
+	s.mu.Unlock()
+}
+
+// SetKnownHostsStore points the TOFU host-key store at a profile's preferences.
+// Must be set before connecting to a regular SSH server; without it such a
+// server cannot be verified and Connect refuses one.
+func (s *SSHClient) SetKnownHostsStore(configDir, profileID string) {
+	s.mu.Lock()
+	s.knownHostsConfigDir = configDir
+	s.knownHostsProfile = profileID
+	s.mu.Unlock()
+}
+
+// TrustHostKey records the fingerprint the user confirmed for a regular server,
+// so the next Connect accepts that exact key and adds it to the known-hosts
+// store. Passing a fingerprint that no longer matches makes the connect fail
+// rather than trust a key that changed since the prompt.
+func (s *SSHClient) TrustHostKey(fingerprint string) {
+	s.mu.Lock()
+	s.trustHostKey = fingerprint
+	s.mu.Unlock()
+}
+
+// Connect dials the SSH server through the NetBird tunnel and performs the
+// SSH handshake. It auto-detects the server type via SSH banner inspection
+// and selects the appropriate authentication path:
+//
+//   - NetBird-SSH server requiring JWT: launches the OAuth 2.0 device-code
+//     flow, opens the verification URL through the registered URLOpener, and
+//     uses the resulting token as the SSH password. Host-key verification
+//     uses the NetBird peer registry.
+//   - NetBird-SSH server without JWT: authenticates with the NetBird SSH
+//     private key. Host-key verification uses the NetBird peer registry.
+//   - Regular SSH server (e.g. OpenSSH): authenticates with the NetBird key
+//     first (so a user-installed NetBird public key works), then falls back
+//     to the supplied password if non-empty. Host-key verification is
+//     trust-on-first-use against the per-profile known-hosts store.
+//
+// The password parameter is only consulted for regular SSH servers.
+func (s *SSHClient) Connect(host string, port int, user, password string) error {
+	if port < 1 || port > 65535 {
+		return fmt.Errorf("invalid port: %d", port)
+	}
+
+	cfg, cfgPath, cc := s.nb.authSnapshot()
+	if cc == nil {
+		return errors.New("netbird client not running")
+	}
+	if cfg == nil {
+		return errors.New("netbird config not loaded")
+	}
+	engine := cc.Engine()
+	if engine == nil {
+		return errors.New("netbird engine not available")
+	}
+
+	s.mu.Lock()
+	s.gen++
+	gen := s.gen
+	s.mu.Unlock()
+
+	serverType := detectServerType(host, port)
+	log.Debugf("SSH server type: %s", serverType)
+
+	authMethods, hostKeyCallback, err := s.buildAuth(cfg, cfgPath, engine, serverType, password)
+	if err != nil {
+		return err
+	}
+
+	clientConfig := &gossh.ClientConfig{
+		User:            user,
+		Auth:            authMethods,
+		HostKeyCallback: hostKeyCallback,
+		Timeout:         sshDialTimeout,
+	}
+	err = s.dialAndHandshake(gen, host, port, clientConfig)
+
+	// An unknown host key is a prompt, not a failure: return the marker intact
+	// (rootCause would unwrap it) so Java can show the fingerprint and retry.
+	var unknownHost *errHostKeyUnknown
+	if errors.As(err, &unknownHost) {
+		return errors.New(unknownHost.Error())
+	}
+
+	// A regular server may still accept a password, so let the caller ask for
+	// one instead of failing. NetBird servers never use a password, so a
+	// failure there is genuine.
+	if err != nil && serverType != detection.ServerTypeNetBirdJWT &&
+		serverType != detection.ServerTypeNetBirdNoJWT && isAuthFailure(err) &&
+		passwordCouldHelp(err, password != "") {
+		return errPasswordRequired
+	}
+	if err != nil {
+		return rootCause(err)
+	}
+	return nil
+}
+
+// StartSession requests a PTY and starts an interactive shell. Output from
+// the session is forwarded to the listener via OnData.
+func (s *SSHClient) StartSession(cols, rows int) error {
+	err := s.startSession(cols, rows)
+	if err != nil {
+		log.Infof("SSH: start session failed: %v", err)
+		return rootCause(err)
+	}
+	return nil
+}
+
+// Write sends data to the SSH session stdin.
+func (s *SSHClient) Write(data []byte) error {
+	s.mu.Lock()
+	stdin := s.stdin
+	s.mu.Unlock()
+	if stdin == nil {
+		return errors.New("ssh session not started")
+	}
+	if _, err := stdin.Write(data); err != nil {
+		return fmt.Errorf("write stdin: %w", err)
+	}
+	return nil
+}
+
+// Resize updates the PTY window size.
+func (s *SSHClient) Resize(cols, rows int) error {
+	s.mu.Lock()
+	session := s.session
+	s.mu.Unlock()
+	if session == nil {
+		return errors.New("ssh session not started")
+	}
+	return session.WindowChange(rows, cols)
+}
+
+// Reset makes a closed client usable for another Connect: Close leaves the
+// one-shot guard set, and clearing it lets the same client back a reconnect.
+func (s *SSHClient) Reset() {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	s.closed = false
+}
+
+// Close terminates the SSH session and underlying connection. Safe to call
+// multiple times.
+func (s *SSHClient) Close() error {
+	s.mu.Lock()
+	s.gen++
+	if s.dialCancel != nil {
+		s.dialCancel()
+		s.dialCancel = nil
+	}
+	sshClient := s.sshClient
+	session := s.session
+	stdin := s.stdin
+	s.sshClient = nil
+	s.session = nil
+	s.stdin = nil
+	notify := !s.closed
+	s.closed = true
+	listener := s.listener
+	s.mu.Unlock()
+
+	if stdin != nil {
+		if err := stdin.Close(); err != nil {
+			log.Debugf("ssh: stdin close: %v", err)
+		}
+	}
+	if session != nil {
+		if err := session.Close(); err != nil && !errors.Is(err, io.EOF) {
+			log.Debugf("ssh: session close: %v", err)
+		}
+	}
+	var firstErr error
+	if sshClient != nil {
+		if err := sshClient.Close(); err != nil {
+			firstErr = err
+		}
+	}
+	if notify && listener != nil {
+		listener.OnClose("closed by client")
+	}
+	return firstErr
+}
+
+func (s *SSHClient) startSession(cols, rows int) error {
+	log.Debugf("SSH: starting session %dx%d", cols, rows)
+	s.mu.Lock()
+	sshClient := s.sshClient
+	gen := s.gen
+	s.mu.Unlock()
+
+	if sshClient == nil {
+		return errors.New("ssh client not connected")
+	}
+
+	pty, err := nbssh.StartPTYSession(sshClient, cols, rows)
+	if err != nil {
+		return err
+	}
+
+	s.mu.Lock()
+	if gen != s.gen {
+		s.mu.Unlock()
+		closeQuiet(pty.Session, "stale session")
+		return errClientClosed
+	}
+	s.session = pty.Session
+	s.stdin = pty.Stdin
+	s.mu.Unlock()
+
+	readerDone := make(chan string, 2)
+	go func() { readerDone <- s.readLoop(pty.Stdout, "stdout") }()
+	go func() { readerDone <- s.readLoop(pty.Stderr, "stderr") }()
+	go func() {
+		reason := <-readerDone
+		if second := <-readerDone; reason == "" {
+			reason = second
+		}
+		s.notifyClose(gen, reason)
+	}()
+	log.Debug("SSH: session started, shell running")
+	return nil
+}
+
+func (s *SSHClient) buildAuth(cfg *profilemanager.Config, cfgPath string, engine *internal.Engine,
+	serverType detection.ServerType, password string) ([]gossh.AuthMethod, gossh.HostKeyCallback, error) {
+
+	switch serverType {
+	case detection.ServerTypeNetBirdJWT:
+		token, err := s.requestJWTToken(cfg, cfgPath)
+		if err != nil {
+			return nil, nil, fmt.Errorf("jwt: %w", err)
+		}
+		auths := []gossh.AuthMethod{gossh.Password(token)}
+		return auths, nbssh.CreateHostKeyCallback(nbssh.PeerKeyLookup(engine.GetPeerSSHKey)), nil
+
+	case detection.ServerTypeNetBirdNoJWT:
+		if cfg.SSHKey == "" {
+			return nil, nil, errors.New("no NetBird SSH key available")
+		}
+		signer, err := gossh.ParsePrivateKey([]byte(cfg.SSHKey))
+		if err != nil {
+			return nil, nil, fmt.Errorf("parse netbird ssh key: %w", err)
+		}
+		auths := []gossh.AuthMethod{gossh.PublicKeys(signer)}
+		return auths, nbssh.CreateHostKeyCallback(nbssh.PeerKeyLookup(engine.GetPeerSSHKey)), nil
+
+	case detection.ServerTypeRegular:
+		var auths []gossh.AuthMethod
+		if cfg.SSHKey != "" {
+			if signer, err := gossh.ParsePrivateKey([]byte(cfg.SSHKey)); err == nil {
+				auths = append(auths, gossh.PublicKeys(signer))
+			} else {
+				log.Debugf("ssh: parse netbird key for regular auth: %v", err)
+			}
+		}
+		if password != "" {
+			pw := password
+			auths = append(auths, gossh.Password(pw))
+			auths = append(auths, gossh.KeyboardInteractive(func(_, _ string, questions []string, _ []bool) ([]string, error) {
+				answers := make([]string, len(questions))
+				for i := range questions {
+					answers[i] = pw
+				}
+				return answers, nil
+			}))
+		}
+		if len(auths) == 0 {
+			// Nothing to offer at all: ask for a password rather than failing,
+			// so the caller can retry once the user supplies one.
+			return nil, nil, errPasswordRequired
+		}
+		callback, err := s.tofuHostKeyCallback()
+		if err != nil {
+			return nil, nil, err
+		}
+		return auths, callback, nil
+
+	default:
+		return nil, nil, fmt.Errorf("unsupported SSH server type: %v", serverType)
+	}
+}
+
+// tofuHostKeyCallback verifies a regular server's host key against the
+// per-profile known-hosts store. An unknown host returns errHostKeyUnknown so
+// Java can show the fingerprint and, once confirmed, retry with the key
+// trusted; a changed key is rejected outright, as OpenSSH does. When the user
+// has confirmed a fingerprint, the callback accepts exactly that key and
+// appends it to the store.
+func (s *SSHClient) tofuHostKeyCallback() (gossh.HostKeyCallback, error) {
+	s.mu.Lock()
+	configDir := s.knownHostsConfigDir
+	profileID := s.knownHostsProfile
+	trusted := s.trustHostKey
+	s.mu.Unlock()
+
+	if configDir == "" || profileID == "" {
+		return nil, errors.New("no known-hosts store configured for regular SSH")
+	}
+
+	store, err := openKnownHostsStore(configDir, profileID)
+	if err != nil {
+		return nil, fmt.Errorf("load known-hosts store: %w", err)
+	}
+
+	return func(hostname string, remote net.Addr, key gossh.PublicKey) error {
+		verdict, err := store.verify(hostname, remote, key)
+		if err != nil {
+			return err
+		}
+		if verdict == hostKeyMatched {
+			return nil
+		}
+		if verdict == hostKeyChanged {
+			return fmt.Errorf("SSH host key changed for %s (possible attack)", hostname)
+		}
+
+		fingerprint := gossh.FingerprintSHA256(key)
+		if trusted == "" {
+			return &errHostKeyUnknown{fingerprint: fingerprint}
+		}
+		if trusted != fingerprint {
+			return fmt.Errorf("SSH host key changed since it was confirmed for %s", hostname)
+		}
+		if err := store.append(hostname, remote, key); err != nil {
+			return fmt.Errorf("persist trusted host key: %w", err)
+		}
+		// The confirmation is spent: now that the key is stored, a later
+		// reconnect must verify against the file, not re-accept this fingerprint.
+		s.mu.Lock()
+		s.trustHostKey = ""
+		s.mu.Unlock()
+		return nil
+	}, nil
+}
+
+func (s *SSHClient) requestJWTToken(cfg *profilemanager.Config, cfgPath string) (string, error) {
+	s.mu.Lock()
+	urlOpener := s.urlOpener
+	s.mu.Unlock()
+	if urlOpener == nil {
+		return "", errors.New("URL opener not configured for JWT auth")
+	}
+
+	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Minute)
+	defer cancel()
+
+	flow, err := auth.NewOAuthFlow(ctx, cfg, false, true, profileLoginHint(cfgPath))
+	if err != nil {
+		return "", fmt.Errorf("create oauth flow: %w", err)
+	}
+
+	// The status callback covers the browser round-trip, which would
+	// otherwise leave the terminal blank.
+	tokenInfo, err := runOAuthFlow(ctx, flow, urlOpener, func() {
+		s.notifyStatus("Waiting for browser authentication...")
+	})
+	if err != nil {
+		return "", err
+	}
+
+	token := tokenInfo.GetTokenToUse()
+	if token == "" {
+		return "", errors.New("empty token returned by IdP")
+	}
+
+	// Tells the client the browser round-trip is over so it can dismiss the
+	// surface it opened, the same way the login and session-extend flows do.
+	// Without it the Custom Tab stays in front of the terminal even though the
+	// token has already been collected.
+	urlOpener.OnLoginSuccess()
+
+	return token, nil
+}
+
+func (s *SSHClient) dialAndHandshake(gen uint64, host string, port int, clientConfig *gossh.ClientConfig) error {
+	addr := net.JoinHostPort(host, strconv.Itoa(port))
+	ctx, cancel := context.WithTimeout(context.Background(), sshDialTimeout)
+	defer cancel()
+
+	s.mu.Lock()
+	if gen != s.gen {
+		s.mu.Unlock()
+		return errClientClosed
+	}
+	s.dialCancel = cancel
+	s.mu.Unlock()
+
+	var dialer net.Dialer
+	conn, err := dialer.DialContext(ctx, "tcp", addr)
+	if err != nil {
+		return fmt.Errorf("dial %s: %w", addr, err)
+	}
+
+	client, err := nbssh.Handshake(ctx, conn, addr, clientConfig)
+	if err != nil {
+		return err
+	}
+
+	s.mu.Lock()
+	if gen != s.gen {
+		s.mu.Unlock()
+		closeQuiet(client, "stale ssh client")
+		return errClientClosed
+	}
+	s.sshClient = client
+	listener := s.listener
+	s.mu.Unlock()
+
+	if listener != nil {
+		listener.OnConnected()
+	}
+	return nil
+}
+
+func (s *SSHClient) readLoop(r io.Reader, name string) string {
+	buf := make([]byte, 4096)
+	for {
+		n, err := r.Read(buf)
+		if n > 0 {
+			s.mu.Lock()
+			listener := s.listener
+			s.mu.Unlock()
+			if listener != nil {
+				chunk := make([]byte, n)
+				copy(chunk, buf[:n])
+				listener.OnData(chunk)
+			}
+		}
+		if err != nil {
+			// EOF is a normal shell exit, so report it without a reason.
+			if errors.Is(err, io.EOF) {
+				return ""
+			}
+			log.Debugf("ssh %s read: %v", name, err)
+			return rootCause(err).Error()
+		}
+	}
+}
+
+// notifyStatus writes a progress line to the terminal through the normal
+// output path, so long steps are visible while nothing else is arriving.
+func (s *SSHClient) notifyStatus(text string) {
+	s.mu.Lock()
+	listener := s.listener
+	s.mu.Unlock()
+	if listener != nil {
+		listener.OnData([]byte("\r\n\x1b[33m" + text + "\x1b[0m\r\n"))
+	}
+}
+
+func (s *SSHClient) notifyClose(gen uint64, reason string) {
+	s.mu.Lock()
+	if gen != s.gen || s.closed {
+		s.mu.Unlock()
+		return
+	}
+	s.closed = true
+	listener := s.listener
+	s.mu.Unlock()
+	if listener != nil {
+		listener.OnClose(reason)
+	}
+}
+
+func closeQuiet(c io.Closer, label string) {
+	if c == nil {
+		return
+	}
+	if err := c.Close(); err != nil && !errors.Is(err, io.EOF) {
+		log.Debugf("ssh: close %s: %v", label, err)
+	}
+}
+
+func detectServerType(host string, port int) detection.ServerType {
+	ctx, cancel := context.WithTimeout(context.Background(), sshDetectionTimeout)
+	defer cancel()
+
+	dialer := &net.Dialer{}
+	serverType, err := detection.DetectSSHServerType(ctx, dialer, host, port)
+	if err != nil {
+		log.Debugf("ssh: server detection failed: %v (assuming regular SSH)", err)
+		return detection.ServerTypeRegular
+	}
+	return serverType
+}
+
+// rootCause returns the innermost error of a %w chain, so the terminal shows
+// "i/o timeout" rather than every layer that added context on the way up.
+func rootCause(err error) error {
+	for {
+		// A joined error has no single root, so keep it as-is.
+		if _, ok := err.(interface{ Unwrap() []error }); ok {
+			return err
+		}
+		next := errors.Unwrap(err)
+		if next == nil {
+			return err
+		}
+		err = next
+	}
+}
+
+// isAuthFailure distinguishes credential rejection from dial, timeout and
+// host-key errors, which retrying with a password would not fix.
+func isAuthFailure(err error) bool {
+	if errors.Is(err, errPasswordRequired) {
+		return true
+	}
+	var partial *gossh.PartialSuccessError
+	if errors.As(err, &partial) {
+		return true
+	}
+	return strings.Contains(err.Error(), "unable to authenticate")
+}
+
+// passwordCouldHelp reports whether prompting for a password again can change
+// the outcome. gossh lists a method under "attempted methods" only when the
+// server offered it, so a supplied password that was never attempted means the
+// server does not accept passwords and the real error should surface instead.
+func passwordCouldHelp(err error, passwordOffered bool) bool {
+	if !passwordOffered {
+		return true
+	}
+	msg := err.Error()
+	return strings.Contains(msg, "password") || strings.Contains(msg, "keyboard-interactive")
+}

client/android/ssh_known_hosts.go

@@ -0,0 +1,168 @@
+//go:build android
+
+package android
+
+import (
+	"bytes"
+	"net"
+	"strconv"
+	"strings"
+	"sync"
+
+	gossh "golang.org/x/crypto/ssh"
+	"golang.org/x/crypto/ssh/knownhosts"
+)
+
+const knownHostsNamespace = "ssh"
+
+const (
+	hostKeyUnknown hostKeyVerdict = iota
+	hostKeyMatched
+	hostKeyChanged
+)
+
+var knownHostsMu sync.Mutex
+
+type hostKeyVerdict uint8
+
+type knownHostsSection struct {
+	KnownHosts []string `json:"knownHosts"`
+}
+
+type knownHostsStore struct {
+	prefs prefsStore
+}
+
+// RemoveKnownHost deletes every known-hosts entry for host:port from the
+// profile's store, so a host trusted for a session that is being deleted does
+// not linger. Java calls this only once no session targets that host, so a
+// shared host stays trusted. A missing entry is not an error: the goal state
+// is "absent".
+func RemoveKnownHost(configDir, profileID, host string, port int) error {
+	store, err := openKnownHostsStore(configDir, profileID)
+	if err != nil {
+		return err
+	}
+	return store.removeHost(host, port)
+}
+
+func openKnownHostsStore(configDir, profileID string) (*knownHostsStore, error) {
+	prefs, err := newProfilePrefs(configDir, profileID)
+	if err != nil {
+		return nil, err
+	}
+	return &knownHostsStore{prefs: prefs}, nil
+}
+
+func (st *knownHostsStore) verify(hostname string, remote net.Addr, key gossh.PublicKey) (hostKeyVerdict, error) {
+	lines, err := st.lines()
+	if err != nil {
+		return hostKeyUnknown, err
+	}
+	targets := knownHostsTargets(hostname, remote)
+
+	verdict := hostKeyUnknown
+	for _, line := range lines {
+		pubKey, ok := knownHostsLineKey(line, targets)
+		if !ok {
+			continue
+		}
+		if pubKey.Type() == key.Type() && bytes.Equal(pubKey.Marshal(), key.Marshal()) {
+			return hostKeyMatched, nil
+		}
+		verdict = hostKeyChanged
+	}
+	return verdict, nil
+}
+
+func (st *knownHostsStore) append(hostname string, remote net.Addr, key gossh.PublicKey) error {
+	line := knownhosts.Line(knownHostsTargets(hostname, remote), key)
+
+	knownHostsMu.Lock()
+	defer knownHostsMu.Unlock()
+
+	lines, err := st.lines()
+	if err != nil {
+		return err
+	}
+	return st.prefs.Put(knownHostsNamespace, knownHostsSection{KnownHosts: append(lines, line)})
+}
+
+func (st *knownHostsStore) removeHost(host string, port int) error {
+	target := knownhosts.Normalize(net.JoinHostPort(host, strconv.Itoa(port)))
+
+	knownHostsMu.Lock()
+	defer knownHostsMu.Unlock()
+
+	lines, err := st.lines()
+	if err != nil {
+		return err
+	}
+	kept := make([]string, 0, len(lines))
+	for _, line := range lines {
+		if knownHostsLineMatches(line, target) {
+			continue
+		}
+		kept = append(kept, line)
+	}
+	if len(kept) == len(lines) {
+		return nil
+	}
+	return st.prefs.Put(knownHostsNamespace, knownHostsSection{KnownHosts: kept})
+}
+
+func (st *knownHostsStore) lines() ([]string, error) {
+	var section knownHostsSection
+	if _, err := st.prefs.Get(knownHostsNamespace, &section); err != nil {
+		return nil, err
+	}
+	return section.KnownHosts, nil
+}
+
+func knownHostsTargets(hostname string, remote net.Addr) []string {
+	targets := []string{knownhosts.Normalize(hostname)}
+	if remote != nil {
+		if normalized := knownhosts.Normalize(remote.String()); normalized != targets[0] {
+			targets = append(targets, normalized)
+		}
+	}
+	return targets
+}
+
+func knownHostsLineKey(line string, targets []string) (gossh.PublicKey, bool) {
+	trimmed := strings.TrimSpace(line)
+	if trimmed == "" || strings.HasPrefix(trimmed, "#") {
+		return nil, false
+	}
+	_, hosts, pubKey, _, _, err := gossh.ParseKnownHosts([]byte(trimmed))
+	if err != nil {
+		return nil, false
+	}
+	for _, host := range hosts {
+		for _, target := range targets {
+			if host == target {
+				return pubKey, true
+			}
+		}
+	}
+	return nil, false
+}
+
+// knownHostsLineMatches reports whether a known-hosts line's address list
+// contains the normalized target. Comment and blank lines never match.
+func knownHostsLineMatches(line, target string) bool {
+	trimmed := strings.TrimSpace(line)
+	if trimmed == "" || strings.HasPrefix(trimmed, "#") {
+		return false
+	}
+	fields := strings.Fields(trimmed)
+	if len(fields) == 0 {
+		return false
+	}
+	for _, addr := range strings.Split(fields[0], ",") {
+		if addr == target {
+			return true
+		}
+	}
+	return false
+}

client/android/ssh_sessions.go

@@ -0,0 +1,104 @@
+//go:build android
+
+package android
+
+const (
+	sshSessionsNamespace = "ssh-sessions"
+	maxStoredSSHSessions = 50
+)
+
+type sshSessionRecord struct {
+	ID   string `json:"id"`
+	Host string `json:"host"`
+	Port int    `json:"port"`
+	User string `json:"user"`
+}
+
+type sshSessionsSection struct {
+	Sessions []sshSessionRecord `json:"sessions"`
+}
+
+// SSHSessionEntry is one stored SSH session, without any credential.
+type SSHSessionEntry struct {
+	ID   string
+	Host string
+	Port int
+	User string
+}
+
+// SSHSessionArray wraps stored SSH sessions for gomobile compatibility.
+type SSHSessionArray struct {
+	items []*SSHSessionEntry
+}
+
+// NewSSHSessionArray creates an empty session array to fill via Add.
+func NewSSHSessionArray() *SSHSessionArray {
+	return &SSHSessionArray{}
+}
+
+// Add appends a session entry, oldest first.
+func (a *SSHSessionArray) Add(id, host string, port int, user string) {
+	a.items = append(a.items, &SSHSessionEntry{ID: id, Host: host, Port: port, User: user})
+}
+
+// Length returns the number of entries.
+func (a *SSHSessionArray) Length() int {
+	return len(a.items)
+}
+
+// Get returns the entry at index i, or nil when out of range.
+func (a *SSHSessionArray) Get(i int) *SSHSessionEntry {
+	if i < 0 || i >= len(a.items) {
+		return nil
+	}
+	return a.items[i]
+}
+
+// SSHSessionStore reads and writes a profile's stored SSH sessions.
+type SSHSessionStore struct {
+	prefs prefsStore
+}
+
+// NewSSHSessionStore opens the session store of the given profile.
+func NewSSHSessionStore(configDir, profileID string) (*SSHSessionStore, error) {
+	prefs, err := newProfilePrefs(configDir, profileID)
+	if err != nil {
+		return nil, err
+	}
+	return &SSHSessionStore{prefs: prefs}, nil
+}
+
+// Load returns the stored sessions, oldest first.
+func (s *SSHSessionStore) Load() (*SSHSessionArray, error) {
+	var section sshSessionsSection
+	if _, err := s.prefs.Get(sshSessionsNamespace, &section); err != nil {
+		return nil, err
+	}
+
+	out := NewSSHSessionArray()
+	for _, record := range section.Sessions {
+		if record.ID == "" || record.Host == "" {
+			continue
+		}
+		out.Add(record.ID, record.Host, record.Port, record.User)
+	}
+	return out, nil
+}
+
+// Save replaces the stored sessions, keeping only the newest entries when the
+// list exceeds the storage cap.
+func (s *SSHSessionStore) Save(sessions *SSHSessionArray) error {
+	var items []*SSHSessionEntry
+	if sessions != nil {
+		items = sessions.items
+	}
+	if len(items) > maxStoredSSHSessions {
+		items = items[len(items)-maxStoredSSHSessions:]
+	}
+
+	records := make([]sshSessionRecord, 0, len(items))
+	for _, item := range items {
+		records = append(records, sshSessionRecord{ID: item.ID, Host: item.Host, Port: item.Port, User: item.User})
+	}
+	return s.prefs.Put(sshSessionsNamespace, sshSessionsSection{Sessions: records})
+}

client/cmd/service_controller.go

@@ -45,8 +45,8 @@ func daemonServerOptions(network string) []grpc.ServerOption {
 		return nil
 	}
 
-	creds := ipcauth.NewTransportCredentials()
-	if creds == nil {
+	creds := ipcauth.NewTransportCredentials() //nolint:staticcheck
+	if creds == nil {                          //nolint:staticcheck // nil only on platforms without a peer-identity primitive
 		log.Warnf("daemon IPC has no peer-identity primitive on %s: privileged operations will be denied", runtime.GOOS)
 		return nil
 	}

client/cmd/service_socket.go

@@ -27,8 +27,8 @@ func listenOnAddress(addr string) (*socketListener, error) {
 	}
 
 	if network == "npipe" {
-		listener, path, err := listenNamedPipe(address)
-		if err != nil {
+		listener, path, err := listenNamedPipe(address) //nolint:staticcheck
+		if err != nil {                                 //nolint:staticcheck // always errors on non-Windows builds
 			return nil, err
 		}
 		return &socketListener{Listener: listener, network: network, address: path}, nil

client/cmd/testutil_test.go

@@ -6,7 +6,7 @@ import (
 	"testing"
 	"time"
 
-	"github.com/golang/mock/gomock"
+	"go.uber.org/mock/gomock"
 	"github.com/stretchr/testify/require"
 	"go.opentelemetry.io/otel"
 	"google.golang.org/grpc"

client/embed/embed.go

@@ -21,7 +21,7 @@ import (
 	"github.com/netbirdio/netbird/client/internal/auth"
 	"github.com/netbirdio/netbird/client/internal/peer"
 	"github.com/netbirdio/netbird/client/internal/profilemanager"
-	sshcommon "github.com/netbirdio/netbird/client/ssh"
+	nbssh "github.com/netbirdio/netbird/client/ssh"
 	"github.com/netbirdio/netbird/client/system"
 	"github.com/netbirdio/netbird/shared/management/domain"
 	mgmProto "github.com/netbirdio/netbird/shared/management/proto"
@@ -521,12 +521,7 @@ func (c *Client) VerifySSHHostKey(peerAddress string, key []byte) error {
 		return err
 	}
 
-	storedKey, found := engine.GetPeerSSHKey(peerAddress)
-	if !found {
-		return sshcommon.ErrPeerNotFound
-	}
-
-	return sshcommon.VerifyHostKey(storedKey, key, peerAddress)
+	return nbssh.PeerKeyLookup(engine.GetPeerSSHKey).VerifySSHHostKey(peerAddress, key)
 }
 
 // SetPerformance retunes a running Client. Only PreallocatedBuffersPerPool

client/embed/embed_test.go

@@ -6,7 +6,7 @@ import (
 	"testing"
 	"time"
 
-	"github.com/golang/mock/gomock"
+	"go.uber.org/mock/gomock"
 	"github.com/stretchr/testify/require"
 	"google.golang.org/grpc"
 

client/firewall/uspfilter/filter_filter_test.go

@@ -5,7 +5,7 @@ import (
 	"net/netip"
 	"testing"
 
-	"github.com/golang/mock/gomock"
+	"go.uber.org/mock/gomock"
 	"github.com/google/gopacket"
 	"github.com/google/gopacket/layers"
 	"github.com/stretchr/testify/require"

client/firewall/uspfilter/filter_routeacl_test.go

@@ -4,7 +4,7 @@ import (
 	"net/netip"
 	"testing"
 
-	"github.com/golang/mock/gomock"
+	"go.uber.org/mock/gomock"
 	"github.com/google/gopacket/layers"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"

client/grpc/dialer_generic.go

@@ -16,28 +16,47 @@ import (
 	"google.golang.org/grpc"
 
 	nbnet "github.com/netbirdio/netbird/client/net"
+	"github.com/netbirdio/netbird/client/netsweep"
 )
 
 func WithCustomDialer(_ bool, _ string) grpc.DialOption {
+	return grpc.WithContextDialer(dialContext)
+}
+
+// WithSweeper dials like WithCustomDialer but registers connections and
+// dials with the sweeper. Append it after WithCustomDialer: gRPC applies
+// dial options in order, so the later context dialer wins.
+func WithSweeper(sweeper *netsweep.Sweeper) grpc.DialOption {
 	return grpc.WithContextDialer(func(ctx context.Context, addr string) (net.Conn, error) {
-		if runtime.GOOS == "linux" {
-			currentUser, err := user.Current()
-			if err != nil {
-				return nil, status.Errorf(codes.FailedPrecondition, "failed to get current user: %v", err)
-			}
+		dial := sweeper.StartDial(ctx)
+		defer dial.Release()
 
-			// the custom dialer requires root permissions which are not required for use cases run as non-root
-			if currentUser.Uid != "0" {
-				log.Debug("Not running as root, using standard dialer")
-				dialer := &net.Dialer{}
-				return dialer.DialContext(ctx, "tcp", addr)
-			}
-		}
-
-		conn, err := nbnet.NewDialer().DialContext(ctx, "tcp", addr)
+		conn, err := dialContext(dial.Ctx(), addr)
 		if err != nil {
-			return nil, fmt.Errorf("nbnet.NewDialer().DialContext: %w", err)
+			return nil, err
 		}
-		return conn, nil
+		return dial.WrapConn(conn)
 	})
 }
+
+func dialContext(ctx context.Context, addr string) (net.Conn, error) {
+	if runtime.GOOS == "linux" {
+		currentUser, err := user.Current()
+		if err != nil {
+			return nil, status.Errorf(codes.FailedPrecondition, "failed to get current user: %v", err)
+		}
+
+		// the custom dialer requires root permissions which are not required for use cases run as non-root
+		if currentUser.Uid != "0" {
+			log.Debug("Not running as root, using standard dialer")
+			dialer := &net.Dialer{}
+			return dialer.DialContext(ctx, "tcp", addr)
+		}
+	}
+
+	conn, err := nbnet.NewDialer().DialContext(ctx, "tcp", addr)
+	if err != nil {
+		return nil, fmt.Errorf("nbnet.NewDialer().DialContext: %w", err)
+	}
+	return conn, nil
+}

client/grpc/dialer_js.go

@@ -3,6 +3,7 @@ package grpc
 import (
 	"google.golang.org/grpc"
 
+	"github.com/netbirdio/netbird/client/netsweep"
 	"github.com/netbirdio/netbird/util/wsproxy/client"
 )
 
@@ -11,3 +12,8 @@ import (
 func WithCustomDialer(tlsEnabled bool, component string) grpc.DialOption {
 	return client.WithWebSocketDialer(tlsEnabled, component)
 }
+
+// WithSweeper is a no-op on WASM/JS: there is no network change signal.
+func WithSweeper(_ *netsweep.Sweeper) grpc.DialOption {
+	return grpc.EmptyDialOption{}
+}

client/grpc/retry.go

@@ -0,0 +1,49 @@
+package grpc
+
+import (
+	"context"
+	"errors"
+	"time"
+
+	"github.com/cenkalti/backoff/v4"
+
+	"github.com/netbirdio/netbird/client/netstate"
+)
+
+// Retry mirrors backoff.Retry, but the sleep between attempts also wakes on
+// OS network availability transitions: an operation cut down by a network
+// change retries the moment the network settles instead of sleeping through
+// the recovery. A nil netState never fires, leaving plain backoff.Retry
+// behavior.
+func Retry(ctx context.Context, operation backoff.Operation, bo backoff.BackOff, netState *netstate.State) error {
+	bo.Reset()
+	for {
+		err := operation()
+		if err == nil {
+			return nil
+		}
+
+		var permanent *backoff.PermanentError
+		if errors.As(err, &permanent) {
+			return permanent.Err
+		}
+
+		next := bo.NextBackOff()
+		if next == backoff.Stop {
+			if cerr := ctx.Err(); cerr != nil {
+				return cerr
+			}
+			return err
+		}
+
+		timer := time.NewTimer(next)
+		select {
+		case <-timer.C:
+		case <-netState.Changed():
+			timer.Stop()
+		case <-ctx.Done():
+			timer.Stop()
+			return ctx.Err()
+		}
+	}
+}

client/grpc/retry_test.go

@@ -0,0 +1,91 @@
+package grpc
+
+import (
+	"context"
+	"errors"
+	"testing"
+	"time"
+
+	"github.com/cenkalti/backoff/v4"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+
+	"github.com/netbirdio/netbird/client/netstate"
+)
+
+func TestRetryWakesOnNetworkChange(t *testing.T) {
+	ns := netstate.New()
+	attempts := 0
+	operation := func() error {
+		attempts++
+		if attempts == 1 {
+			return errors.New("cut by network change")
+		}
+		return nil
+	}
+
+	go func() {
+		time.Sleep(20 * time.Millisecond)
+		ns.Set(false)
+	}()
+
+	start := time.Now()
+	err := Retry(context.Background(), operation, backoff.NewConstantBackOff(time.Minute), ns)
+
+	require.NoError(t, err)
+	assert.Equal(t, 2, attempts, "network change must cause one immediate retry")
+	assert.Less(t, time.Since(start), time.Second, "the transition must cut the minute-long sleep short")
+}
+
+func TestRetryPermanentError(t *testing.T) {
+	sentinel := errors.New("permission denied")
+	operation := func() error {
+		return backoff.Permanent(sentinel)
+	}
+
+	err := Retry(context.Background(), operation, backoff.NewConstantBackOff(time.Millisecond), nil)
+	assert.ErrorIs(t, err, sentinel, "permanent errors must stop retries")
+}
+
+func TestRetryNilNetState(t *testing.T) {
+	attempts := 0
+	operation := func() error {
+		attempts++
+		if attempts < 3 {
+			return errors.New("transient")
+		}
+		return nil
+	}
+
+	err := Retry(context.Background(), operation, backoff.NewConstantBackOff(time.Millisecond), nil)
+	require.NoError(t, err)
+	assert.Equal(t, 3, attempts, "nil network state must preserve timed retries")
+}
+
+func TestRetryStops(t *testing.T) {
+	failure := errors.New("still failing")
+	operation := func() error {
+		return failure
+	}
+
+	err := Retry(context.Background(), operation, &backoff.StopBackOff{}, nil)
+	assert.ErrorIs(t, err, failure, "stop backoff must return the operation error")
+}
+
+func TestRetryCtxCancelDuringSleep(t *testing.T) {
+	ctx, cancel := context.WithCancel(context.Background())
+	operation := func() error {
+		return errors.New("failing")
+	}
+
+	go func() {
+		time.Sleep(20 * time.Millisecond)
+		cancel()
+	}()
+
+	start := time.Now()
+	err := Retry(ctx, operation, backoff.NewConstantBackOff(time.Minute), netstate.New())
+
+	assert.ErrorIs(t, err, context.Canceled, "context cancellation must stop the retry loop")
+	assert.Less(t, time.Since(start), time.Second, "context cancellation must interrupt backoff sleep")
+}

client/iface/device/device_filter_test.go

@@ -4,7 +4,7 @@ import (
 	"net"
 	"testing"
 
-	"github.com/golang/mock/gomock"
+	"go.uber.org/mock/gomock"
 	"github.com/google/gopacket"
 	"github.com/google/gopacket/layers"
 

client/iface/mocks/filter.go

@@ -8,7 +8,7 @@ import (
 	"net/netip"
 	reflect "reflect"
 
-	gomock "github.com/golang/mock/gomock"
+	gomock "go.uber.org/mock/gomock"
 )
 
 // MockPacketFilter is a mock of PacketFilter interface.

client/iface/mocks/tun.go

@@ -8,7 +8,7 @@ import (
 	os "os"
 	reflect "reflect"
 
-	gomock "github.com/golang/mock/gomock"
+	gomock "go.uber.org/mock/gomock"
 	tun "golang.zx2c4.com/wireguard/tun"
 )
 

client/iface/wgproxy/bind/proxy.go

@@ -53,15 +53,15 @@ func NewProxyBind(bind Bind, mtu uint16) *ProxyBind {
 	return p
 }
 
-// AddTurnConn adds a new connection to the bind.
+// AddRelayedConn adds a new connection to the bind.
 // endpoint is the NetBird address of the remote peer. The SetEndpoint return with the address what will be used in the
 // WireGuard configuration.
 //
 // Parameters:
 //   - ctx: Context is used for proxyToLocal to avoid unnecessary error messages
 //   - nbAddr: The NetBird UDP address of the remote peer, it required to generate fake address
-//   - remoteConn: The established TURN connection to the remote peer
-func (p *ProxyBind) AddTurnConn(ctx context.Context, nbAddr *net.UDPAddr, remoteConn net.Conn) error {
+//   - remoteConn: The established relayed connection to the remote peer
+func (p *ProxyBind) AddRelayedConn(ctx context.Context, nbAddr *net.UDPAddr, remoteConn net.Conn) error {
 	fakeNetIP, err := fakeAddress(nbAddr)
 	if err != nil {
 		return err

client/iface/wgproxy/ebpf/proxy.go

@@ -30,9 +30,9 @@ type WGEBPFProxy struct {
 	proxyPort         int
 	mtu               uint16
 
-	ebpfManager   ebpfMgr.Manager
-	turnConnStore map[uint16]net.Conn
-	turnConnMutex sync.Mutex
+	ebpfManager      ebpfMgr.Manager
+	relayedConnStore map[uint16]net.Conn
+	relayedConnMutex sync.Mutex
 
 	lastUsedPort uint16
 	rawConnIPv4  net.PacketConn
@@ -50,7 +50,7 @@ func NewWGEBPFProxy(wgPort int, mtu uint16) *WGEBPFProxy {
 		localWGListenPort: wgPort,
 		mtu:               mtu,
 		ebpfManager:       ebpf.GetEbpfManagerInstance(),
-		turnConnStore:     make(map[uint16]net.Conn),
+		relayedConnStore:  make(map[uint16]net.Conn),
 	}
 	return wgProxy
 }
@@ -110,14 +110,14 @@ func (p *WGEBPFProxy) Listen() error {
 	return nil
 }
 
-// AddTurnConn add new turn connection for the proxy
-func (p *WGEBPFProxy) AddTurnConn(turnConn net.Conn) (*net.UDPAddr, error) {
-	wgEndpointPort, err := p.storeTurnConn(turnConn)
+// AddRelayedConn add new relayed connection for the proxy
+func (p *WGEBPFProxy) AddRelayedConn(relayedConn net.Conn) (*net.UDPAddr, error) {
+	wgEndpointPort, err := p.storeRelayedConn(relayedConn)
 	if err != nil {
 		return nil, err
 	}
 
-	log.Infof("turn conn added to wg proxy store: %s, endpoint port: :%d", turnConn.RemoteAddr(), wgEndpointPort)
+	log.Infof("relayed conn added to wg proxy store: %s, endpoint port: :%d", relayedConn.RemoteAddr(), wgEndpointPort)
 
 	wgEndpoint := &net.UDPAddr{
 		IP:   net.ParseIP(loopbackAddr),
@@ -186,48 +186,48 @@ func (p *WGEBPFProxy) readAndForwardPacket(buf []byte) error {
 		return fmt.Errorf("failed to read UDP packet from WG: %w", err)
 	}
 
-	p.turnConnMutex.Lock()
-	conn, ok := p.turnConnStore[uint16(addr.Port)]
-	p.turnConnMutex.Unlock()
+	p.relayedConnMutex.Lock()
+	conn, ok := p.relayedConnStore[uint16(addr.Port)]
+	p.relayedConnMutex.Unlock()
 	if !ok {
 		if p.ctx.Err() == nil {
-			log.Debugf("turn conn not found by port because conn already has been closed: %d", addr.Port)
+			log.Debugf("relayed conn not found by port because conn already has been closed: %d", addr.Port)
 		}
 		return nil
 	}
 
 	if _, err := conn.Write(buf[:n]); err != nil {
-		return fmt.Errorf("failed to forward local WG packet (%d) to remote turn conn: %w", addr.Port, err)
+		return fmt.Errorf("forward local WG packet (%d) to remote relayed conn: %w", addr.Port, err)
 	}
 	return nil
 }
 
-func (p *WGEBPFProxy) storeTurnConn(turnConn net.Conn) (uint16, error) {
-	p.turnConnMutex.Lock()
-	defer p.turnConnMutex.Unlock()
+func (p *WGEBPFProxy) storeRelayedConn(relayedConn net.Conn) (uint16, error) {
+	p.relayedConnMutex.Lock()
+	defer p.relayedConnMutex.Unlock()
 
 	np, err := p.nextFreePort()
 	if err != nil {
 		return np, err
 	}
-	p.turnConnStore[np] = turnConn
+	p.relayedConnStore[np] = relayedConn
 	return np, nil
 }
 
-func (p *WGEBPFProxy) removeTurnConn(turnConnID uint16) {
-	p.turnConnMutex.Lock()
-	defer p.turnConnMutex.Unlock()
+func (p *WGEBPFProxy) removeRelayedConn(relayedConnID uint16) {
+	p.relayedConnMutex.Lock()
+	defer p.relayedConnMutex.Unlock()
 
-	_, ok := p.turnConnStore[turnConnID]
+	_, ok := p.relayedConnStore[relayedConnID]
 	if ok {
-		log.Debugf("remove turn conn from store by port: %d", turnConnID)
+		log.Debugf("remove relayed conn from store by port: %d", relayedConnID)
 	}
-	delete(p.turnConnStore, turnConnID)
+	delete(p.relayedConnStore, relayedConnID)
 }
 
 func (p *WGEBPFProxy) nextFreePort() (uint16, error) {
-	if len(p.turnConnStore) == 65535 {
-		return 0, fmt.Errorf("reached maximum turn connection numbers")
+	if len(p.relayedConnStore) == 65535 {
+		return 0, fmt.Errorf("reached maximum relayed connection numbers")
 	}
 generatePort:
 	if p.lastUsedPort == 65535 {
@@ -236,7 +236,7 @@ generatePort:
 		p.lastUsedPort++
 	}
 
-	if _, ok := p.turnConnStore[p.lastUsedPort]; ok {
+	if _, ok := p.relayedConnStore[p.lastUsedPort]; ok {
 		goto generatePort
 	}
 	return p.lastUsedPort, nil

client/iface/wgproxy/ebpf/proxy_test.go

@@ -9,32 +9,32 @@ import (
 func TestWGEBPFProxy_connStore(t *testing.T) {
 	wgProxy := NewWGEBPFProxy(1, 1280)
 
-	p, _ := wgProxy.storeTurnConn(nil)
+	p, _ := wgProxy.storeRelayedConn(nil)
 	if p != 1 {
 		t.Errorf("invalid initial port: %d", wgProxy.lastUsedPort)
 	}
 
 	numOfConns := 10
 	for i := 0; i < numOfConns; i++ {
-		p, _ = wgProxy.storeTurnConn(nil)
+		p, _ = wgProxy.storeRelayedConn(nil)
 	}
 	if p != uint16(numOfConns)+1 {
 		t.Errorf("invalid last used port: %d, expected: %d", p, numOfConns+1)
 	}
-	if len(wgProxy.turnConnStore) != numOfConns+1 {
-		t.Errorf("invalid store size: %d, expected: %d", len(wgProxy.turnConnStore), numOfConns+1)
+	if len(wgProxy.relayedConnStore) != numOfConns+1 {
+		t.Errorf("invalid store size: %d, expected: %d", len(wgProxy.relayedConnStore), numOfConns+1)
 	}
 }
 
 func TestWGEBPFProxy_portCalculation_overflow(t *testing.T) {
 	wgProxy := NewWGEBPFProxy(1, 1280)
 
-	_, _ = wgProxy.storeTurnConn(nil)
+	_, _ = wgProxy.storeRelayedConn(nil)
 	wgProxy.lastUsedPort = 65535
-	p, _ := wgProxy.storeTurnConn(nil)
+	p, _ := wgProxy.storeRelayedConn(nil)
 
-	if len(wgProxy.turnConnStore) != 2 {
-		t.Errorf("invalid store size: %d, expected: %d", len(wgProxy.turnConnStore), 2)
+	if len(wgProxy.relayedConnStore) != 2 {
+		t.Errorf("invalid store size: %d, expected: %d", len(wgProxy.relayedConnStore), 2)
 	}
 
 	if p != 2 {
@@ -46,11 +46,11 @@ func TestWGEBPFProxy_portCalculation_maxConn(t *testing.T) {
 	wgProxy := NewWGEBPFProxy(1, 1280)
 
 	for i := 0; i < 65535; i++ {
-		_, _ = wgProxy.storeTurnConn(nil)
+		_, _ = wgProxy.storeRelayedConn(nil)
 	}
 
-	_, err := wgProxy.storeTurnConn(nil)
+	_, err := wgProxy.storeRelayedConn(nil)
 	if err == nil {
-		t.Errorf("invalid turn conn store calculation")
+		t.Errorf("invalid relayed conn store calculation")
 	}
 }

client/iface/wgproxy/ebpf/wrapper.go

@@ -121,10 +121,10 @@ func NewProxyWrapper(proxy *WGEBPFProxy) *ProxyWrapper {
 	}
 }
 
-func (p *ProxyWrapper) AddTurnConn(ctx context.Context, _ *net.UDPAddr, remoteConn net.Conn) error {
-	addr, err := p.wgeBPFProxy.AddTurnConn(remoteConn)
+func (p *ProxyWrapper) AddRelayedConn(ctx context.Context, _ *net.UDPAddr, remoteConn net.Conn) error {
+	addr, err := p.wgeBPFProxy.AddRelayedConn(remoteConn)
 	if err != nil {
-		return fmt.Errorf("add turn conn: %w", err)
+		return fmt.Errorf("add relayed conn: %w", err)
 	}
 
 	headers, err := NewPacketHeaders(p.wgeBPFProxy.localWGListenPort, addr)
@@ -252,7 +252,7 @@ func (p *ProxyWrapper) CloseConn() error {
 }
 
 func (p *ProxyWrapper) proxyToLocal(ctx context.Context) {
-	defer p.wgeBPFProxy.removeTurnConn(uint16(p.wgRelayedEndpointAddr.Port))
+	defer p.wgeBPFProxy.removeRelayedConn(uint16(p.wgRelayedEndpointAddr.Port))
 
 	buf := make([]byte, p.wgeBPFProxy.mtu+bufsize.WGBufferOverhead)
 	for {
@@ -273,7 +273,7 @@ func (p *ProxyWrapper) proxyToLocal(ctx context.Context) {
 			if ctx.Err() != nil {
 				return
 			}
-			log.Errorf("failed to write out turn pkg to local conn: %v", err)
+			log.Errorf("failed to write out relayed pkg to local conn: %v", err)
 		}
 	}
 }
@@ -286,7 +286,7 @@ func (p *ProxyWrapper) readFromRemote(ctx context.Context, buf []byte) (int, err
 		}
 		p.closeListener.Notify()
 		if !errors.Is(err, io.EOF) {
-			log.Errorf("failed to read from turn conn (endpoint: :%d): %s", p.wgRelayedEndpointAddr.Port, err)
+			log.Errorf("failed to read from relayed conn (endpoint: :%d): %s", p.wgRelayedEndpointAddr.Port, err)
 		}
 		return 0, err
 	}

client/iface/wgproxy/proxy.go

@@ -7,7 +7,7 @@ import (
 
 // Proxy is a transfer layer between the relayed connection and the WireGuard
 type Proxy interface {
-	AddTurnConn(ctx context.Context, endpoint *net.UDPAddr, remoteConn net.Conn) error
+	AddRelayedConn(ctx context.Context, endpoint *net.UDPAddr, remoteConn net.Conn) error
 	EndpointAddr() *net.UDPAddr // EndpointAddr returns the address of the WireGuard peer endpoint
 	Work()                      // Work start or resume the proxy
 	Pause()                     // Pause to forward the packages from remote connection to WireGuard. The opposite way still works.

client/iface/wgproxy/proxy_test.go

@@ -95,7 +95,7 @@ func TestProxyCloseByRemoteConn(t *testing.T) {
 		t.Run(tt.name, func(t *testing.T) {
 			addr, _ := net.ResolveUDPAddr("udp", "100.108.135.221:51892")
 			relayedConn := newMockConn()
-			err := tt.proxy.AddTurnConn(ctx, addr, relayedConn)
+			err := tt.proxy.AddRelayedConn(ctx, addr, relayedConn)
 			if err != nil {
 				t.Errorf("error: %v", err)
 			}
@@ -157,7 +157,7 @@ func redirectTraffic(t *testing.T, proxy Proxy, wgPort int, endPointAddr *net.UD
 		_ = relayedServer.Close()
 	}()
 
-	if err := proxy.AddTurnConn(context.Background(), endPointAddr, relayedConn); err != nil {
+	if err := proxy.AddRelayedConn(context.Background(), endPointAddr, relayedConn); err != nil {
 		t.Errorf("error: %v", err)
 	}
 	defer func() {

client/iface/wgproxy/redirect_test.go

@@ -119,9 +119,9 @@ func testRedirectAs(t *testing.T, proxy Proxy, wgPort int, nbAddr, p2pEndpoint *
 	}
 	defer relayConn.Close()
 
-	// Add TURN connection to proxy
-	if err := proxy.AddTurnConn(ctx, nbAddr, relayConn); err != nil {
-		t.Fatalf("failed to add TURN connection: %v", err)
+	// Add relayed connection to proxy
+	if err := proxy.AddRelayedConn(ctx, nbAddr, relayConn); err != nil {
+		t.Fatalf("failed to add relayed connection: %v", err)
 	}
 	defer func() {
 		if err := proxy.CloseConn(); err != nil {
@@ -304,8 +304,8 @@ func TestRedirectAs_Multiple_Switches(t *testing.T) {
 		Port: 38746,
 	}
 
-	if err := proxy.AddTurnConn(ctx, nbAddr, relayConn); err != nil {
-		t.Fatalf("failed to add TURN connection: %v", err)
+	if err := proxy.AddRelayedConn(ctx, nbAddr, relayConn); err != nil {
+		t.Fatalf("failed to add relayed connection: %v", err)
 	}
 	defer func() {
 		if err := proxy.CloseConn(); err != nil {

client/iface/wgproxy/udp/proxy.go

@@ -51,12 +51,12 @@ func NewWGUDPProxy(wgPort int, mtu uint16) *WGUDPProxy {
 	return p
 }
 
-// AddTurnConn
+// AddRelayedConn dials the local WireGuard port and stores the relayed connection.
 // The provided Context must be non-nil. If the context expires before
 // the connection is complete, an error is returned. Once successfully
 // connected, any expiration of the context will not affect the
 // connection.
-func (p *WGUDPProxy) AddTurnConn(ctx context.Context, _ *net.UDPAddr, remoteConn net.Conn) error {
+func (p *WGUDPProxy) AddRelayedConn(ctx context.Context, _ *net.UDPAddr, remoteConn net.Conn) error {
 	dialer := net.Dialer{}
 	localConn, err := dialer.DialContext(ctx, "udp", fmt.Sprintf(":%d", p.localWGListenPort))
 	if err != nil {

client/internal/acl/manager.go

@@ -116,11 +116,11 @@ func (d *DefaultManager) ApplyFiltering(networkMap *mgmProto.NetworkMap, dnsRout
 // firewall state, so an identical hash means an identical resulting ruleset.
 func (d *DefaultManager) firewallConfigHash(networkMap *mgmProto.NetworkMap, dnsRouteFeatureFlag bool) (uint64, error) {
 	return hashstructure.Hash(struct {
-		PeerRules            []*mgmProto.FirewallRule
-		PeerRulesIsEmpty     bool
-		RouteRules           []*mgmProto.RouteFirewallRule
-		RouteRulesIsEmpty    bool
-		DNSRouteFeatureFlag  bool
+		PeerRules           []*mgmProto.FirewallRule
+		PeerRulesIsEmpty    bool
+		RouteRules          []*mgmProto.RouteFirewallRule
+		RouteRulesIsEmpty   bool
+		DNSRouteFeatureFlag bool
 	}{
 		PeerRules:           networkMap.GetFirewallRules(),
 		PeerRulesIsEmpty:    networkMap.GetFirewallRulesIsEmpty(),
@@ -144,13 +144,13 @@ func (d *DefaultManager) applyPeerACLs(networkMap *mgmProto.NetworkMap) {
 		log.Warn("this peer is connected to a NetBird Management service with an older version. Allowing all traffic from connected peers")
 		rules = append(rules,
 			&mgmProto.FirewallRule{
-				PeerIP:    "0.0.0.0",
+				PeerIP:    "0.0.0.0", //nolint:staticcheck
 				Direction: mgmProto.RuleDirection_IN,
 				Action:    mgmProto.RuleAction_ACCEPT,
 				Protocol:  mgmProto.RuleProtocol_ALL,
 			},
 			&mgmProto.FirewallRule{
-				PeerIP:    "0.0.0.0",
+				PeerIP:    "0.0.0.0", //nolint:staticcheck
 				Direction: mgmProto.RuleDirection_OUT,
 				Action:    mgmProto.RuleAction_ACCEPT,
 				Protocol:  mgmProto.RuleProtocol_ALL,
@@ -407,7 +407,6 @@ func (d *DefaultManager) getRuleGroupingSelector(rule *mgmProto.FirewallRule) st
 	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).

client/internal/acl/manager_test.go

@@ -5,9 +5,9 @@ import (
 	"net/netip"
 	"testing"
 
-	"github.com/golang/mock/gomock"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
+	"go.uber.org/mock/gomock"
 
 	"github.com/netbirdio/netbird/client/firewall"
 	"github.com/netbirdio/netbird/client/iface"
@@ -87,7 +87,7 @@ func TestDefaultManager(t *testing.T) {
 		networkMap.FirewallRules = append(
 			networkMap.FirewallRules,
 			&mgmProto.FirewallRule{
-				PeerIP:    "10.93.0.3",
+				PeerIP:    "10.93.0.3", //nolint:staticcheck
 				Direction: mgmProto.RuleDirection_IN,
 				Action:    mgmProto.RuleAction_DROP,
 				Protocol:  mgmProto.RuleProtocol_ICMP,
@@ -556,12 +556,12 @@ func TestApplyFilteringSkipsUnchangedConfig(t *testing.T) {
 
 func buildNetworkMap(peerRules, routeRules int) *mgmProto.NetworkMap {
 	nm := &mgmProto.NetworkMap{
-		FirewallRulesIsEmpty:      peerRules == 0,
+		FirewallRulesIsEmpty:       peerRules == 0,
 		RoutesFirewallRulesIsEmpty: routeRules == 0,
 	}
 	for i := range peerRules {
 		nm.FirewallRules = append(nm.FirewallRules, &mgmProto.FirewallRule{
-			PeerIP:    fmt.Sprintf("10.%d.%d.%d", i>>16&0xff, i>>8&0xff, i&0xff),
+			PeerIP:    fmt.Sprintf("10.%d.%d.%d", i>>16&0xff, i>>8&0xff, i&0xff), //nolint:staticcheck
 			Direction: mgmProto.RuleDirection_IN,
 			Action:    mgmProto.RuleAction_ACCEPT,
 			Protocol:  mgmProto.RuleProtocol_TCP,

client/internal/acl/mocks/iface_mapper.go

@@ -7,7 +7,7 @@ package mocks
 import (
 	reflect "reflect"
 
-	gomock "github.com/golang/mock/gomock"
+	gomock "go.uber.org/mock/gomock"
 	wgdevice "golang.zx2c4.com/wireguard/device"
 
 	"github.com/netbirdio/netbird/client/iface/device"

client/internal/auth/auth.go

@@ -138,26 +138,37 @@ func (a *Auth) IsSSOSupported(ctx context.Context) (bool, error) {
 
 // GetOAuthFlow returns an OAuth flow (PKCE or Device) using the existing management connection
 // This avoids creating a new connection to the management server
-func (a *Auth) GetOAuthFlow(ctx context.Context, forceDeviceAuth bool) (OAuthFlow, error) {
+func (a *Auth) GetOAuthFlow(ctx context.Context, forceDeviceAuth bool, hint string) (OAuthFlow, error) {
 	var flow OAuthFlow
-	var err error
 
-	err = a.withRetry(ctx, func(client *mgm.GrpcClient) error {
+	err := a.withRetry(ctx, func(client *mgm.GrpcClient) error {
 		if forceDeviceAuth {
-			flow, err = a.getDeviceFlow(client)
-			return err
+			deviceFlow, err := a.getDeviceFlow(client)
+			if err != nil {
+				return err
+			}
+			deviceFlow.SetLoginHint(hint)
+			flow = deviceFlow
+			return nil
 		}
 
 		// Try PKCE flow first
-		flow, err = a.getPKCEFlow(client)
+		pkceFlow, err := a.getPKCEFlow(client)
 		if err != nil {
 			// If PKCE not supported, try Device flow
 			if s, ok := status.FromError(err); ok && (s.Code() == codes.NotFound || s.Code() == codes.Unimplemented) {
-				flow, err = a.getDeviceFlow(client)
-				return err
+				deviceFlow, err := a.getDeviceFlow(client)
+				if err != nil {
+					return err
+				}
+				deviceFlow.SetLoginHint(hint)
+				flow = deviceFlow
+				return nil
 			}
 			return err
 		}
+		pkceFlow.SetLoginHint(hint)
+		flow = pkceFlow
 		return nil
 	})
 

client/internal/auth/oauth.go

@@ -97,9 +97,7 @@ func authenticateWithPKCEFlow(ctx context.Context, config *profilemanager.Config
 		return nil, fmt.Errorf("getting pkce authorization flow info failed with error: %v", err)
 	}
 
-	if hint != "" {
-		pkceFlowInfo.SetLoginHint(hint)
-	}
+	pkceFlowInfo.SetLoginHint(hint)
 
 	return pkceFlowInfo, nil
 }
@@ -127,9 +125,7 @@ func authenticateWithDeviceCodeFlow(ctx context.Context, config *profilemanager.
 		}
 	}
 
-	if hint != "" {
-		deviceFlowInfo.SetLoginHint(hint)
-	}
+	deviceFlowInfo.SetLoginHint(hint)
 
 	return deviceFlowInfo, nil
 }

client/internal/connect.go

@@ -38,6 +38,8 @@ import (
 	"github.com/netbirdio/netbird/client/internal/updater"
 	"github.com/netbirdio/netbird/client/internal/updater/installer"
 	nbnet "github.com/netbirdio/netbird/client/net"
+	"github.com/netbirdio/netbird/client/netstate"
+	"github.com/netbirdio/netbird/client/netsweep"
 	cProto "github.com/netbirdio/netbird/client/proto"
 	"github.com/netbirdio/netbird/client/ssh"
 	sshconfig "github.com/netbirdio/netbird/client/ssh/config"
@@ -70,18 +72,42 @@ type ConnectClient struct {
 	updateManager *updater.Manager
 
 	persistSyncResponse bool
+
+	// netState gates every reconnection loop on OS-reported network
+	// availability. Nil (the default) disables gating; mobile platforms
+	// inject it via WithNetworkState.
+	netState *netstate.State
+
+	// sweeper cuts the management, signal and relay connections on network
+	// change; nil disables it.
+	sweeper *netsweep.Sweeper
+}
+
+// ConnectClientOption configures optional ConnectClient behavior.
+type ConnectClientOption func(*ConnectClient)
+
+// WithNetworkState injects the OS network availability state that gates every
+// reconnection loop; without it gating is disabled.
+func WithNetworkState(netState *netstate.State) ConnectClientOption {
+	return func(c *ConnectClient) { c.netState = netState }
+}
+
+// WithSweeper injects the network change sweeper.
+func WithSweeper(sweeper *netsweep.Sweeper) ConnectClientOption {
+	return func(c *ConnectClient) { c.sweeper = sweeper }
 }
 
 func NewConnectClient(
 	ctx context.Context,
 	config *profilemanager.Config,
 	statusRecorder *peer.Status,
+	opts ...ConnectClientOption,
 ) *ConnectClient {
 	// Derive the run context here so Stop owns the cancel that unblocks the run
 	// loop. runCancel is set once at construction, so Stop can call it without
 	// racing the run loop's startup. Callers therefore need not cancel before Stop.
 	runCtx, runCancel := context.WithCancel(ctx)
-	return &ConnectClient{
+	c := &ConnectClient{
 		ctx:            runCtx,
 		runCancel:      runCancel,
 		runExited:      make(chan struct{}),
@@ -89,6 +115,10 @@ func NewConnectClient(
 		statusRecorder: statusRecorder,
 		engineMutex:    sync.Mutex{},
 	}
+	for _, opt := range opts {
+		opt(c)
+	}
+	return c
 }
 
 func (c *ConnectClient) SetUpdateManager(um *updater.Manager) {
@@ -274,6 +304,13 @@ func (c *ConnectClient) run(mobileDependency MobileDependency, runningChan chan
 			return nil
 		}
 
+		// suspend connection attempts while the OS reports no usable network
+		if waited, err := c.netState.Wait(c.ctx); err != nil {
+			return nil
+		} else if waited {
+			backOff.Reset()
+		}
+
 		state.Set(StatusConnecting)
 
 		engineCtx, cancel := context.WithCancel(c.ctx)
@@ -285,7 +322,8 @@ func (c *ConnectClient) run(mobileDependency MobileDependency, runningChan chan
 		}()
 
 		log.Debugf("connecting to the Management service %s", c.config.ManagementURL.Host)
-		mgmClient, err := mgm.NewClient(engineCtx, c.config.ManagementURL.Host, myPrivateKey, mgmTlsEnabled)
+		mgmClient, err := mgm.NewClient(engineCtx, c.config.ManagementURL.Host, myPrivateKey, mgmTlsEnabled,
+			mgm.WithNetworkState(c.netState), mgm.WithSweeper(c.sweeper))
 		if err != nil {
 			// On daemon shutdown / Down() the parent context is cancelled
 			// and the dial fails with "context canceled". Wrapping that
@@ -360,7 +398,7 @@ func (c *ConnectClient) run(mobileDependency MobileDependency, runningChan chan
 		}()
 
 		// with the global Netbird config in hand connect (just a connection, no stream yet) Signal
-		signalClient, err := connectToSignal(engineCtx, loginResp.GetNetbirdConfig(), myPrivateKey)
+		signalClient, err := connectToSignal(engineCtx, loginResp.GetNetbirdConfig(), myPrivateKey, c.netState, c.sweeper)
 		if err != nil {
 			log.Error(err)
 			return wrapErr(err)
@@ -396,7 +434,8 @@ func (c *ConnectClient) run(mobileDependency MobileDependency, runningChan chan
 			engineConfig.StateDir = filepath.Dir(path)
 		}
 
-		relayManager := relayClient.NewManager(engineCtx, relayURLs, myPrivateKey.PublicKey().String(), engineConfig.MTU)
+		relayManager := relayClient.NewManager(engineCtx, relayURLs, myPrivateKey.PublicKey().String(), engineConfig.MTU,
+			relayClient.WithNetworkState(c.netState), relayClient.WithSweeper(c.sweeper))
 		c.statusRecorder.SetRelayMgr(relayManager)
 		if len(relayURLs) > 0 {
 			if token != nil {
@@ -424,6 +463,7 @@ func (c *ConnectClient) run(mobileDependency MobileDependency, runningChan chan
 			UpdateManager:  c.updateManager,
 			ClientMetrics:  c.clientMetrics,
 			MetricsCtx:     c.ctx,
+			NetState:       c.netState,
 		}, mobileDependency)
 		engine.SetSyncResponsePersistence(c.persistSyncResponse)
 		c.engine = engine
@@ -480,6 +520,16 @@ func (c *ConnectClient) run(mobileDependency MobileDependency, runningChan chan
 	// status stream stuck at Connecting.
 	err = backoff.Retry(operation, backoff.WithContext(backOff, c.ctx))
 	if err != nil {
+		// Once the client context is cancelled backoff.WithContext surfaces the
+		// bare context error, and any attempt torn down mid-flight reports the
+		// same. That cancellation is the caller asking us to stop (Stop, Down or
+		// an engine restart), so exit cleanly instead of handing back a failure
+		// the caller would have to distinguish from a real one.
+		if c.ctx.Err() != nil && errors.Is(err, context.Canceled) {
+			log.Info("exiting client retry loop, context cancelled")
+			return nil
+		}
+
 		log.Debugf("exiting client retry loop due to unrecoverable error: %s", err)
 		if s, ok := gstatus.FromError(err); ok && (s.Code() == codes.PermissionDenied) {
 			state.Set(StatusNeedsLogin)
@@ -673,7 +723,7 @@ func selectMTU(localMTU uint16, peerMTU int32) uint16 {
 }
 
 // connectToSignal creates Signal Service client and established a connection
-func connectToSignal(ctx context.Context, wtConfig *mgmProto.NetbirdConfig, ourPrivateKey wgtypes.Key) (*signal.GrpcClient, error) {
+func connectToSignal(ctx context.Context, wtConfig *mgmProto.NetbirdConfig, ourPrivateKey wgtypes.Key, netState *netstate.State, sweeper *netsweep.Sweeper) (*signal.GrpcClient, error) {
 	var sigTLSEnabled bool
 	if wtConfig.Signal.Protocol == mgmProto.HostConfig_HTTPS {
 		sigTLSEnabled = true
@@ -681,7 +731,8 @@ func connectToSignal(ctx context.Context, wtConfig *mgmProto.NetbirdConfig, ourP
 		sigTLSEnabled = false
 	}
 
-	signalClient, err := signal.NewClient(ctx, wtConfig.Signal.Uri, ourPrivateKey, sigTLSEnabled)
+	signalClient, err := signal.NewClient(ctx, wtConfig.Signal.Uri, ourPrivateKey, sigTLSEnabled,
+		signal.WithNetworkState(netState), signal.WithSweeper(sweeper))
 	if err != nil {
 		log.Errorf("error while connecting to the Signal Exchange Service %s: %s", wtConfig.Signal.Uri, err)
 		return nil, gstatus.Errorf(codes.FailedPrecondition, "failed connecting to Signal Service : %s", err)

client/internal/daemonaddr/identity.go

@@ -0,0 +1,17 @@
+package daemonaddr
+
+import "strings"
+
+// CarriesIdentity reports whether the control channel at addr conveys the
+// connecting process's identity to the daemon. A Unix socket carries peer
+// credentials and a named pipe carries the client's token. Nothing else does, TCP
+// included, and there the daemon can authorize a privileged operation for nobody
+// at all: see ResolveDaemonAddr, which says as much to anyone still reaching the
+// Windows daemon on the address it served before it had a pipe.
+//
+// A client uses this to tell whether becoming privileged would get it anywhere.
+// It answers from the scheme and nothing else, so an address it does not
+// recognise counts as carrying no identity.
+func CarriesIdentity(addr string) bool {
+	return strings.HasPrefix(addr, "unix://") || strings.HasPrefix(addr, pipeScheme)
+}

client/internal/daemonaddr/identity_test.go

@@ -0,0 +1,29 @@
+package daemonaddr
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestCarriesIdentity(t *testing.T) {
+	tests := []struct {
+		addr string
+		want bool
+	}{
+		{"unix:///var/run/netbird.sock", true},
+		{"unix:///var/run/netbird/default.sock", true},
+		{"npipe://netbird", true},
+		{`npipe://\\.\pipe\ProtectedPrefix\Administrators\netbird`, true},
+		{"tcp://127.0.0.1:41731", false},
+		{"tcp://localhost:41731", false},
+		{"", false},
+		{"/var/run/netbird.sock", false},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.addr, func(t *testing.T) {
+			assert.Equal(t, tt.want, CarriesIdentity(tt.addr), "address %q", tt.addr)
+		})
+	}
+}

client/internal/dns/host_windows.go

@@ -35,6 +35,8 @@ var (
 // exported so a diagnostic reader reports the same locations that are written.
 const (
 	// NRPTKeyPrefix starts the name of every NRPT rule key this client creates.
+	// Older versions used different layouts under the same prefix: a single
+	// unsuffixed key, then one key per domain, now one key per batch of domains.
 	NRPTKeyPrefix = "NetBird-Match"
 
 	// DNSPolicyConfigRoot holds the NRPT rules of the local policy store.
@@ -89,7 +91,6 @@ type registryConfigurator struct {
 	guid            string
 	routingAll      bool
 	gpo             bool
-	nrptEntryCount  int
 	origNameservers []netip.Addr
 }
 
@@ -322,14 +323,9 @@ func (r *registryConfigurator) applyDNSConfig(config HostDNSConfig, stateManager
 	}
 
 	if len(matchDomains) != 0 {
-		count, err := r.addDNSMatchPolicy(matchDomains, config.ServerIP)
-		// Update count even on error to ensure cleanup covers partially created rules
-		r.nrptEntryCount = count
-		if err != nil {
+		if err := r.addDNSMatchPolicy(matchDomains, config.ServerIP); err != nil {
 			return fmt.Errorf("add dns match policy: %w", err)
 		}
-	} else {
-		r.nrptEntryCount = 0
 	}
 
 	r.updateState(stateManager)
@@ -345,9 +341,8 @@ func (r *registryConfigurator) applyDNSConfig(config HostDNSConfig, stateManager
 
 func (r *registryConfigurator) updateState(stateManager *statemanager.Manager) {
 	if err := stateManager.UpdateState(&ShutdownState{
-		Guid:           r.guid,
-		GPO:            r.gpo,
-		NRPTEntryCount: r.nrptEntryCount,
+		Guid: r.guid,
+		GPO:  r.gpo,
 	}); err != nil {
 		log.Errorf("failed to update shutdown state: %s", err)
 	}
@@ -362,7 +357,7 @@ func (r *registryConfigurator) addDNSSetupForAll(ip netip.Addr) error {
 	return nil
 }
 
-func (r *registryConfigurator) addDNSMatchPolicy(domains []string, ip netip.Addr) (int, error) {
+func (r *registryConfigurator) addDNSMatchPolicy(domains []string, ip netip.Addr) error {
 	// if the gpo key is present, we need to put our DNS settings there, otherwise our config might be ignored
 	// see https://learn.microsoft.com/en-us/openspecs/windows_protocols/ms-gpnrpt/8cc31cb9-20cb-4140-9e85-3e08703b4745
 
@@ -379,19 +374,17 @@ func (r *registryConfigurator) addDNSMatchPolicy(domains []string, ip netip.Addr
 		gpoPath := fmt.Sprintf("%s-%d", gpoDnsPolicyConfigMatchPath, ruleIndex)
 
 		if err := r.configureDNSPolicy(localPath, batchDomains, ip); err != nil {
-			return ruleIndex, fmt.Errorf("configure DNS Local policy for rule %d: %w", ruleIndex, err)
+			return fmt.Errorf("configure DNS Local policy for rule %d: %w", ruleIndex, err)
 		}
 
-		// Increment immediately so the caller's cleanup path knows about this rule
-		ruleIndex++
-
 		if r.gpo {
 			if err := r.configureDNSPolicy(gpoPath, batchDomains, ip); err != nil {
-				return ruleIndex, fmt.Errorf("configure gpo DNS policy for rule %d: %w", ruleIndex-1, err)
+				return fmt.Errorf("configure gpo DNS policy for rule %d: %w", ruleIndex, err)
 			}
 		}
 
-		log.Debugf("added NRPT rule %d with %d domains", ruleIndex-1, len(batchDomains))
+		log.Debugf("added NRPT rule %d with %d domains", ruleIndex, len(batchDomains))
+		ruleIndex++
 	}
 
 	if r.gpo {
@@ -401,7 +394,7 @@ func (r *registryConfigurator) addDNSMatchPolicy(domains []string, ip netip.Addr
 	}
 
 	log.Infof("added %d NRPT rules for %d domains", ruleIndex, len(domains))
-	return ruleIndex, nil
+	return nil
 }
 
 func (r *registryConfigurator) configureDNSPolicy(policyPath string, domains []string, ip netip.Addr) error {
@@ -466,7 +459,7 @@ func (r *registryConfigurator) flushDNSCache() {
 
 	ret, _, err := dnsFlushResolverCacheFn.Call()
 	if ret == 0 {
-		if err != nil && !errors.Is(err, syscall.Errno(0)) {
+		if !errors.Is(err, syscall.Errno(0)) {
 			log.Errorf("DnsFlushResolverCache failed: %v", err)
 			return
 		}
@@ -534,28 +527,28 @@ func (r *registryConfigurator) restoreHostDNS() error {
 	return nil
 }
 
+// removeDNSMatchPolicies deletes every NRPT rule this client may have created,
+// from the local and the GPO policy store. The rules are found by enumerating
+// the registry, the only authoritative record of what was written. Cleanup must
+// not depend on a rule count: the in-memory one is scoped to a single
+// registryConfigurator and the persisted one is deleted on every clean
+// disconnect, and a rule left behind keeps resolving names over an interface
+// that is gone, until reboot discards the volatile key.
 func (r *registryConfigurator) removeDNSMatchPolicies() error {
 	var merr *multierror.Error
 
-	// Try to remove the base entries (for backward compatibility)
-	if err := removeRegistryKeyFromDNSPolicyConfig(dnsPolicyConfigMatchPath); err != nil {
-		merr = multierror.Append(merr, fmt.Errorf("remove local base entry: %w", err))
-	}
-
-	if err := removeRegistryKeyFromDNSPolicyConfig(gpoDnsPolicyConfigMatchPath); err != nil {
-		merr = multierror.Append(merr, fmt.Errorf("remove GPO base entry: %w", err))
-	}
-
-	for i := 0; i < r.nrptEntryCount; i++ {
-		localPath := fmt.Sprintf("%s-%d", dnsPolicyConfigMatchPath, i)
-		gpoPath := fmt.Sprintf("%s-%d", gpoDnsPolicyConfigMatchPath, i)
-
-		if err := removeRegistryKeyFromDNSPolicyConfig(localPath); err != nil {
-			merr = multierror.Append(merr, fmt.Errorf("remove local entry %d: %w", i, err))
+	for _, root := range []string{DNSPolicyConfigRoot, GPODNSPolicyConfigRoot} {
+		names, err := listNRPTRuleKeys(root)
+		if err != nil {
+			merr = multierror.Append(merr, fmt.Errorf("list rule keys under %s: %w", root, err))
+			continue
 		}
 
-		if err := removeRegistryKeyFromDNSPolicyConfig(gpoPath); err != nil {
-			merr = multierror.Append(merr, fmt.Errorf("remove GPO entry %d: %w", i, err))
+		for _, name := range names {
+			path := root + `\` + name
+			if err := removeRegistryKeyFromDNSPolicyConfig(path); err != nil {
+				merr = multierror.Append(merr, fmt.Errorf("remove entry %s: %w", path, err))
+			}
 		}
 	}
 
@@ -570,6 +563,39 @@ func (r *registryConfigurator) restoreUncleanShutdownDNS() error {
 	return r.restoreHostDNS()
 }
 
+// listNRPTRuleKeys returns the names of our NRPT rule keys under a policy store
+// root. An absent root holds nothing to clean up, which is the normal state of
+// the GPO store on a machine without DNS Client policy.
+func listNRPTRuleKeys(root string) ([]string, error) {
+	k, err := registry.OpenKey(registry.LOCAL_MACHINE, root, registry.ENUMERATE_SUB_KEYS)
+	switch {
+	case errors.Is(err, registry.ErrNotExist), errors.Is(err, syscall.ERROR_PATH_NOT_FOUND):
+		// the GPO store is absent on a machine without DNS client policy
+		log.Debugf("HKEY_LOCAL_MACHINE\\%s does not exist", root)
+		return nil, nil
+	case err != nil:
+		// any other failure has to reach the caller: reporting no rules would
+		// report a successful cleanup while leaving the rules in place
+		return nil, fmt.Errorf("open HKEY_LOCAL_MACHINE\\%s: %w", root, err)
+	}
+	defer closer(k)
+
+	names, err := k.ReadSubKeyNames(-1)
+	if err != nil {
+		return nil, fmt.Errorf("read subkey names: %w", err)
+	}
+
+	var ruleKeys []string
+	for _, name := range names {
+		// registry key names are case insensitive
+		if strings.HasPrefix(strings.ToLower(name), strings.ToLower(NRPTKeyPrefix)) {
+			ruleKeys = append(ruleKeys, name)
+		}
+	}
+
+	return ruleKeys, nil
+}
+
 func removeRegistryKeyFromDNSPolicyConfig(regKeyPath string) error {
 	k, err := registry.OpenKey(registry.LOCAL_MACHINE, regKeyPath, registry.QUERY_VALUE)
 	if err != nil {
@@ -601,7 +627,7 @@ func refreshGroupPolicy() error {
 	)
 
 	if ret == 0 {
-		if err != nil && !errors.Is(err, syscall.Errno(0)) {
+		if !errors.Is(err, syscall.Errno(0)) {
 			return fmt.Errorf("RefreshPolicyEx failed: %w", err)
 		}
 		return fmt.Errorf("RefreshPolicyEx failed")

client/internal/dns/host_windows_test.go

@@ -25,7 +25,7 @@ func TestNRPTEntriesCleanupOnConfigChange(t *testing.T) {
 
 	// Create a test interface registry key so updateSearchDomains doesn't fail
 	testGUID := "{12345678-1234-1234-1234-123456789ABC}"
-	interfacePath := `SYSTEM\CurrentControlSet\Services\Tcpip\Parameters\Interfaces\` + testGUID
+	interfacePath := InterfaceConfigPath + `\` + testGUID
 	testKey, _, err := registry.CreateKey(registry.LOCAL_MACHINE, interfacePath, registry.SET_VALUE)
 	require.NoError(t, err, "Should create test interface registry key")
 	testKey.Close()
@@ -56,7 +56,7 @@ func TestNRPTEntriesCleanupOnConfigChange(t *testing.T) {
 	require.NoError(t, err)
 
 	// Verify 3 NRPT rules exist
-	assert.Equal(t, 3, cfg.nrptEntryCount, "Should create 3 NRPT rules for 125 domains")
+	assert.Equal(t, 3, countNRPTRuleKeys(t), "Should create 3 NRPT rules for 125 domains")
 	for i := 0; i < 3; i++ {
 		exists, err := registryKeyExists(fmt.Sprintf("%s-%d", dnsPolicyConfigMatchPath, i))
 		require.NoError(t, err)
@@ -81,7 +81,7 @@ func TestNRPTEntriesCleanupOnConfigChange(t *testing.T) {
 	require.NoError(t, err)
 
 	// Verify first 2 NRPT rules exist
-	assert.Equal(t, 2, cfg.nrptEntryCount, "Should create 2 NRPT rules for 75 domains")
+	assert.Equal(t, 2, countNRPTRuleKeys(t), "Should create 2 NRPT rules for 75 domains")
 	for i := 0; i < 2; i++ {
 		exists, err := registryKeyExists(fmt.Sprintf("%s-%d", dnsPolicyConfigMatchPath, i))
 		require.NoError(t, err)
@@ -106,9 +106,65 @@ func registryKeyExists(path string) (bool, error) {
 	return true, nil
 }
 
+// TestNRPTCleanupWithoutRuleCount verifies that rules written by a previous run
+// are removed by a configurator that has no record of how many there are: an
+// unclean exit loses the in-memory count and a clean disconnect deletes the
+// persisted one, so cleanup cannot depend on either.
+func TestNRPTCleanupWithoutRuleCount(t *testing.T) {
+	if testing.Short() {
+		t.Skip("skipping registry integration test in short mode")
+	}
+
+	defer cleanupRegistryKeys(t)
+	cleanupRegistryKeys(t)
+
+	testIP := netip.MustParseAddr("100.64.0.1")
+
+	// 75 domains produce two indexed rules, as the current layout does
+	domains := make([]string, 75)
+	for i := range domains {
+		domains[i] = fmt.Sprintf(".domain%d.com", i+1)
+	}
+
+	previousRun := &registryConfigurator{}
+	require.NoError(t, previousRun.addDNSMatchPolicy(domains, testIP))
+
+	// the unsuffixed key an older version would have written
+	require.NoError(t, previousRun.configureDNSPolicy(dnsPolicyConfigMatchPath, []string{".legacy.example.com"}, testIP))
+
+	// a policy owned by someone else, which cleanup must not touch
+	foreignPath := DNSPolicyConfigRoot + `\DnsPolicyConfigTestForeign`
+	foreignKey, _, err := registry.CreateKey(registry.LOCAL_MACHINE, foreignPath, registry.SET_VALUE)
+	require.NoError(t, err, "Should create foreign policy key")
+	foreignKey.Close()
+	defer func() {
+		_ = registry.DeleteKey(registry.LOCAL_MACHINE, foreignPath)
+	}()
+
+	require.Equal(t, 3, countNRPTRuleKeys(t), "Should have two indexed rules and the legacy one")
+
+	// a configurator that never applied a DNS config, as one built after a
+	// restart or from a shutdown state without a count is
+	freshRun := &registryConfigurator{}
+	require.NoError(t, freshRun.removeDNSMatchPolicies())
+
+	assert.Equal(t, 0, countNRPTRuleKeys(t), "Should remove every rule left by the previous run")
+
+	exists, err := registryKeyExists(foreignPath)
+	require.NoError(t, err)
+	assert.True(t, exists, "Should not remove a policy that is not ours")
+}
+
+func countNRPTRuleKeys(t *testing.T) int {
+	t.Helper()
+
+	names, err := listNRPTRuleKeys(DNSPolicyConfigRoot)
+	require.NoError(t, err, "Should list NRPT rule keys")
+	return len(names)
+}
+
 func cleanupRegistryKeys(*testing.T) {
-	// Clean up more entries to account for batching tests with many domains
-	cfg := &registryConfigurator{nrptEntryCount: 20}
+	cfg := &registryConfigurator{}
 	_ = cfg.removeDNSMatchPolicies()
 }
 
@@ -125,7 +181,7 @@ func TestNRPTDomainBatching(t *testing.T) {
 
 	// Create a test interface registry key so updateSearchDomains doesn't fail
 	testGUID := "{12345678-1234-1234-1234-123456789ABC}"
-	interfacePath := `SYSTEM\CurrentControlSet\Services\Tcpip\Parameters\Interfaces\` + testGUID
+	interfacePath := InterfaceConfigPath + `\` + testGUID
 	testKey, _, err := registry.CreateKey(registry.LOCAL_MACHINE, interfacePath, registry.SET_VALUE)
 	require.NoError(t, err, "Should create test interface registry key")
 	testKey.Close()
@@ -193,7 +249,7 @@ func TestNRPTDomainBatching(t *testing.T) {
 			require.NoError(t, err)
 
 			// Verify that exactly expectedRuleCount rules were created
-			assert.Equal(t, tc.expectedRuleCount, cfg.nrptEntryCount,
+			assert.Equal(t, tc.expectedRuleCount, countNRPTRuleKeys(t),
 				"Should create %d NRPT rules for %d domains", tc.expectedRuleCount, tc.domainCount)
 
 			// Verify all expected rules exist

client/internal/dns/response_writer_test.go

@@ -4,7 +4,7 @@ import (
 	"net"
 	"testing"
 
-	"github.com/golang/mock/gomock"
+	"go.uber.org/mock/gomock"
 	"github.com/google/gopacket"
 	"github.com/google/gopacket/layers"
 	"github.com/miekg/dns"

client/internal/dns/server_privileged_test.go

@@ -9,7 +9,7 @@ import (
 	"os"
 	"testing"
 
-	"github.com/golang/mock/gomock"
+	"go.uber.org/mock/gomock"
 	"github.com/miekg/dns"
 	"github.com/stretchr/testify/assert"
 	"golang.zx2c4.com/wireguard/wgctrl/wgtypes"

client/internal/dns/unclean_shutdown_windows.go

@@ -5,9 +5,8 @@ import (
 )
 
 type ShutdownState struct {
-	Guid           string
-	GPO            bool
-	NRPTEntryCount int
+	Guid string
+	GPO  bool
 }
 
 func (s *ShutdownState) Name() string {
@@ -16,9 +15,8 @@ func (s *ShutdownState) Name() string {
 
 func (s *ShutdownState) Cleanup() error {
 	manager := &registryConfigurator{
-		guid:           s.Guid,
-		gpo:            s.GPO,
-		nrptEntryCount: s.NRPTEntryCount,
+		guid: s.Guid,
+		gpo:  s.GPO,
 	}
 
 	if err := manager.restoreUncleanShutdownDNS(); err != nil {

client/internal/dnsfwd/manager.go

@@ -101,7 +101,7 @@ func (m *Manager) Start(fwdEntries []*ForwarderEntry) error {
 	m.dnsForwarder = NewDNSForwarder(listenAddress, dnsTTL, m.firewall, m.statusRecorder, m.wgIface)
 
 	go func() {
-		if err := m.dnsForwarder.Listen(fwdEntries); err != nil {
+		if err := m.dnsForwarder.Listen(fwdEntries); err != nil { //nolint:staticcheck
 			// todo handle close error if it is exists
 			log.Errorf("failed to start DNS forwarder, err: %v", err)
 		}

client/internal/ebpf/ebpf/manager_linux.go

@@ -2,17 +2,21 @@ package ebpf
 
 import (
 	_ "embed"
+	"fmt"
 	"net"
 	"sync"
 
 	"github.com/cilium/ebpf/link"
 	"github.com/cilium/ebpf/rlimit"
 	log "github.com/sirupsen/logrus"
+	"golang.org/x/sys/unix"
 
 	"github.com/netbirdio/netbird/client/internal/ebpf/manager"
 )
 
 const (
+	xdpProgName = "nb_xdp_prog"
+
 	mapKeyFeatures uint32 = 0
 
 	featureFlagWGProxy      = 0b00000001
@@ -68,21 +72,50 @@ func (tf *GeneralManager) loadXdp() error {
 		return err
 	}
 
-	// load pre-compiled programs into the kernel.
-	err = loadBpfObjects(&tf.bpfObjs, nil)
+	// lo has no native XDP, so the program runs in generic mode. Unless it
+	// declares multi-buffer support the kernel must linearize every non-linear
+	// skb before running it. Loopback packets are up to 64 KB, so that is a
+	// contiguous GFP_ATOMIC allocation per packet, and when it fails the packet
+	// is dropped before the program runs, stalling local TCP connections.
+	// Multi-buffer XDP in generic mode requires kernel 6.3, so fall back to a
+	// plain attach when the kernel rejects it.
+	err = tf.attachXdp(iFace.Index, true)
+	if err == nil {
+		return nil
+	}
+	log.Debugf("failed to attach multi-buffer xdp program, retrying without it: %s", err)
+
+	return tf.attachXdp(iFace.Index, false)
+}
+
+func (tf *GeneralManager) attachXdp(iFaceIndex int, multiBuffer bool) error {
+	spec, err := loadBpf()
 	if err != nil {
-		return err
+		return fmt.Errorf("load bpf spec: %w", err)
+	}
+
+	if multiBuffer {
+		prog, ok := spec.Programs[xdpProgName]
+		if !ok {
+			return fmt.Errorf("program %s not found in bpf spec", xdpProgName)
+		}
+		prog.Flags |= unix.BPF_F_XDP_HAS_FRAGS
+	}
+
+	if err := spec.LoadAndAssign(&tf.bpfObjs, nil); err != nil {
+		return fmt.Errorf("load bpf objects: %w", err)
 	}
 
 	tf.link, err = link.AttachXDP(link.XDPOptions{
 		Program:   tf.bpfObjs.NbXdpProg,
-		Interface: iFace.Index,
+		Interface: iFaceIndex,
 	})
-
 	if err != nil {
-		_ = tf.bpfObjs.Close()
+		if closeErr := tf.bpfObjs.Close(); closeErr != nil {
+			log.Debugf("failed to close bpf objects after xdp attach error: %s", closeErr)
+		}
 		tf.link = nil
-		return err
+		return fmt.Errorf("attach xdp: %w", err)
 	}
 	return nil
 }

client/internal/elevate/elevate.go

@@ -0,0 +1,74 @@
+// Package elevate re-runs this very executable under the operating system's own
+// privilege-elevation mechanism and waits for it to finish.
+//
+// It exists so that a change the daemon restricts to root/administrator can be
+// authorized from the GUI, by the user, at the moment they ask for it: Windows
+// shows the UAC consent dialog, macOS the system authentication dialog, and
+// Linux/FreeBSD the session's polkit agent. The credentials, where any are
+// asked for, are collected by the operating system and never pass through
+// NetBird.
+//
+// What the elevated process then does is the caller's business: it is the same
+// binary, in a one-shot mode, and it is authorized by the daemon exactly like
+// any other privileged caller, from the identity the kernel reports on the
+// control channel. Nothing here grants privilege, and the daemon gains no new
+// way to be talked into something: elevation only changes who is calling it.
+package elevate
+
+import (
+	"context"
+	"errors"
+
+	log "github.com/sirupsen/logrus"
+)
+
+// AppliedMarker is what the elevated process prints on standard output once it has
+// done what it was run for.
+//
+// macOS's AuthorizationExecuteWithPrivileges reports no exit status and does not
+// say which process it started, so there this line is the only evidence that the
+// change was applied. The other platforms have an exit code and ignore it.
+const AppliedMarker = "netbird-elevated: applied"
+
+var (
+	// ErrDeclined reports that the user dismissed the prompt or did not
+	// authenticate. Nothing happened and nothing is wrong: a caller undoes its
+	// optimistic update and stays quiet.
+	ErrDeclined = errors.New("authorization declined")
+
+	// ErrUnavailable reports that this host has no elevation mechanism we can
+	// drive: no polkit on a Unix desktop, or an executable we decline to run as
+	// root. A caller falls back to telling the user which command to run.
+	ErrUnavailable = errors.New("no privilege elevation mechanism available")
+)
+
+// Run runs this executable with args under the platform's elevation mechanism
+// and waits for it to exit. A non-zero exit is returned as an error, so the
+// caller can treat a completed Run as the operation having succeeded.
+//
+// The args are the caller's own command line, so they cross no privilege
+// boundary: only a user who has just authenticated as an administrator can get
+// them run at all.
+func Run(ctx context.Context, args ...string) error {
+	self, err := trustedSelf()
+	if err != nil {
+		return err
+	}
+	return run(ctx, self, args)
+}
+
+// Available reports whether Run has a mechanism to use on this host, so a caller
+// can offer the prompt only when there is one and otherwise fall back to
+// guidance the user can act on. It answers from what is installed, not from what
+// the user is allowed to do: an administrator's password may still be required
+// and may still not be given, which is ErrDeclined from Run.
+func Available() bool {
+	if _, err := trustedSelf(); err != nil {
+		// Worth a line: this is also what a build run from a group-writable
+		// directory hits, and there is nothing in the UI to say why the offer is
+		// missing.
+		log.Debugf("not offering privilege elevation: %v", err)
+		return false
+	}
+	return mechanismAvailable()
+}

client/internal/elevate/output.go

@@ -0,0 +1,18 @@
+package elevate
+
+import "strings"
+
+// noOutput stands in for a process that said nothing, so that a report of what it
+// said still reads as a sentence.
+const noOutput = "no output"
+
+func firstLine(s string) string {
+	s = strings.TrimSpace(s)
+	if s == "" {
+		return noOutput
+	}
+	if i := strings.IndexByte(s, '\n'); i >= 0 {
+		return s[:i]
+	}
+	return s
+}

client/internal/elevate/output_test.go

@@ -0,0 +1,21 @@
+package elevate
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestFirstLine(t *testing.T) {
+	tests := []struct{ in, want string }{
+		{in: "", want: noOutput},
+		{in: "  \n ", want: noOutput},
+		{in: "one line", want: "one line"},
+		{in: "first\nsecond", want: "first"},
+		{in: "\nsecond\n", want: "second"},
+	}
+
+	for _, tt := range tests {
+		assert.Equal(t, tt.want, firstLine(tt.in), "input %q", tt.in)
+	}
+}

client/internal/elevate/run_darwin.go

@@ -0,0 +1,359 @@
+package elevate
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"os"
+	"runtime"
+	"strings"
+	"sync"
+	"syscall"
+	"unsafe"
+
+	"github.com/ebitengine/purego"
+	log "github.com/sirupsen/logrus"
+)
+
+// Authorization Services, reached through purego rather than cgo so the released
+// binaries keep building with CGO_ENABLED=0.
+//
+// The prompt belongs to this process, which is what makes it carry the
+// application's name and our own explanation. Going through osascript instead puts
+// the very same trampoline behind a dialog attributed to osascript, and means
+// handing a shell a command line to re-parse.
+//
+// # On AuthorizationExecuteWithPrivileges
+//
+// It is deprecated, and Apple's guidance (Quinn, "BSD Privilege Escalation on
+// macOS", developer.apple.com/forums/thread/708765) is "while it still works, it's
+// been deprecated for many years. Do not use it in a widely distributed product."
+// It is used here anyway, knowingly, because the alternatives Apple offers are for
+// *obtaining* ongoing privileges — an installer package, SMAppService, SMJobBless —
+// and NetBird already has what they would install: a launchd daemon running as
+// root. What is missing is only a way for an unprivileged client to ask it to act.
+//
+// The way to that without a deprecated call is to authorize the client instead of
+// elevating one: the app takes the right with AuthorizationCreate, passes the
+// AuthorizationExternalForm to the daemon, and the daemon checks it with
+// AuthorizationCopyRights before acting — none of which is deprecated. It is the
+// better design and it is where this should end up. It also means the daemon
+// accepting an authorization over its control socket, which is a new way to be
+// asked for privileged work and wants reviewing as such, so it is deliberately not
+// bundled in with the rest of this.
+//
+// Until then, three things keep the deprecation from being a trap. Every symbol is
+// resolved with an error rather than a panic, so a macOS that has dropped this
+// function leaves the app offering the user a command instead of crashing on the
+// way to a prompt. A failure to run the tool is reported as ErrUnavailable, so the
+// fallback is the same one an agent-less Linux session gets. And the whole path
+// runs under guard, which turns a panic out of the FFI layer into that same
+// fallback.
+//
+// The trampoline passes on the environment it was given, so what it starts as root
+// must be an executable this user's peers cannot influence: that is what
+// trustedSelf refuses, and what signing the binary settles for the loader.
+
+const (
+	securityFramework = "/System/Library/Frameworks/Security.framework/Security"
+	libSystem         = "/usr/lib/libSystem.B.dylib"
+
+	// trampoline is what the framework hands the tool to. Present on every macOS,
+	// and worth confirming before offering a prompt rather than mid-prompt.
+	trampoline = "/usr/libexec/security_authtrampoline"
+)
+
+// rightExecute is the right an administrator holds, and what
+// AuthorizationExecuteWithPrivileges requires of us.
+const rightExecute = "system.privilege.admin"
+
+// promptKey is kAuthorizationEnvironmentPrompt, which puts a sentence of ours above
+// the system's in the dialog. It is about the change rather than the mechanism.
+const (
+	promptKey  = "prompt"
+	promptText = "NetBird needs to change a setting that grants SSH access to this computer."
+)
+
+// OSStatus values from SecBase.h that mean something to us; anything else is
+// reported as it comes.
+const (
+	errAuthorizationSuccess               = 0
+	errAuthorizationDenied                = -60005
+	errAuthorizationCanceled              = -60006
+	errAuthorizationInteractionNotAllowed = -60007
+	errAuthorizationToolExecuteFailure    = -60031
+	errAuthorizationToolEnvironmentError  = -60032
+)
+
+// AuthorizationFlags from Authorization.h.
+const (
+	flagDefaults           = 0
+	flagInteractionAllowed = 1 << 0
+	flagExtendRights       = 1 << 1
+	flagDestroyRights      = 1 << 3
+	flagPreAuthorize       = 1 << 4
+)
+
+// authorizationItem mirrors AuthorizationItem: a name, and a value the name gives
+// meaning to. 32 bytes on both amd64 and arm64.
+type authorizationItem struct {
+	name        *byte
+	valueLength uintptr
+	value       unsafe.Pointer
+	// flags is reserved by the API and always zero. Declared because the layout
+	// is the contract: without it the struct is 24 bytes where C reads 32.
+	flags uint32 //nolint:unused // part of the C layout
+}
+
+// authorizationItemSet mirrors AuthorizationItemSet, which serves as both an
+// AuthorizationRights and an AuthorizationEnvironment.
+type authorizationItemSet struct {
+	count uint32
+	items *authorizationItem
+}
+
+var (
+	authorizationCreate                func(rights, environment *authorizationItemSet, flags uint32, authorization *uintptr) int32
+	authorizationExecuteWithPrivileges func(authorization uintptr, pathToTool string, options uint32, arguments *uintptr, communicationsPipe *uintptr) int32
+	authorizationFree                  func(authorization uintptr, flags uint32) int32
+	fileno                             func(stream uintptr) int32
+	fclose                             func(stream uintptr) int32
+
+	loadOnce sync.Once
+	loadErr  error
+)
+
+// load resolves the functions once. A framework that cannot be opened, or a symbol
+// that is no longer there, leaves the host without a mechanism rather than taking
+// the process down with it: see the note on deprecation above.
+func load() error {
+	loadOnce.Do(func() { loadErr = guard("loading Security.framework", resolve) })
+	return loadErr
+}
+
+// guard turns a panic out of the FFI layer into an error, so an API that has
+// changed under us costs the user a prompt rather than the window they were
+// clicking in. purego panics on a signature it cannot map, and this is the one
+// place in the client that calls a deprecated system function.
+//
+// It catches Go panics, which is what purego raises. A fault inside the framework
+// itself is not a panic and not recoverable; the layout the tests pin down is what
+// stands between us and that.
+func guard(what string, fn func() error) (err error) {
+	defer func() {
+		r := recover()
+		if r == nil {
+			return
+		}
+		log.Errorf("%s panicked: %v", what, r)
+		err = fmt.Errorf("%w: %s: %v", ErrUnavailable, what, r)
+	}()
+	return fn()
+}
+
+func resolve() error {
+	security, err := purego.Dlopen(securityFramework, purego.RTLD_LAZY|purego.RTLD_GLOBAL)
+	if err != nil {
+		return fmt.Errorf("open %s: %w", securityFramework, err)
+	}
+	system, err := purego.Dlopen(libSystem, purego.RTLD_LAZY|purego.RTLD_GLOBAL)
+	if err != nil {
+		return fmt.Errorf("open %s: %w", libSystem, err)
+	}
+
+	// purego.RegisterLibFunc panics on a symbol it cannot find, which is not how a
+	// deprecated function's disappearance should reach the user.
+	for _, fn := range []struct {
+		ptr    any
+		handle uintptr
+		name   string
+	}{
+		{&authorizationCreate, security, "AuthorizationCreate"},
+		{&authorizationExecuteWithPrivileges, security, "AuthorizationExecuteWithPrivileges"},
+		{&authorizationFree, security, "AuthorizationFree"},
+		{&fileno, system, "fileno"},
+		{&fclose, system, "fclose"},
+	} {
+		symbol, err := purego.Dlsym(fn.handle, fn.name)
+		if err != nil {
+			return fmt.Errorf("resolve %s: %w", fn.name, err)
+		}
+		if symbol == 0 {
+			return fmt.Errorf("resolve %s: not present on this system", fn.name)
+		}
+		purego.RegisterFunc(fn.ptr, symbol)
+	}
+	return nil
+}
+
+// run asks the system to run self as root: first for the right, which is what puts
+// up the authentication dialog and collects the password or takes the Touch ID,
+// then for the tool. The credentials go to the system's authorization trampoline
+// and never to us.
+//
+// The context bounds only our own waiting; the dialog belongs to the system and
+// closes when the user answers it.
+func run(ctx context.Context, self string, args []string) error {
+	if err := load(); err != nil {
+		return fmt.Errorf("%w: %v", ErrUnavailable, err)
+	}
+
+	return guard("asking for privileges", func() error {
+		authorization, err := authorize()
+		if err != nil {
+			return err
+		}
+		defer authorizationFree(authorization, flagDestroyRights)
+
+		return execute(ctx, authorization, self, args)
+	})
+}
+
+func mechanismAvailable() bool {
+	if err := load(); err != nil {
+		return false
+	}
+	info, err := os.Stat(trampoline)
+	return err == nil && !info.IsDir()
+}
+
+// authorize obtains the right, prompting for it. A dismissed dialog comes back as
+// errAuthorizationCanceled and a password given up on as errAuthorizationDenied;
+// both are the user's answer rather than a failure.
+func authorize() (uintptr, error) {
+	var pinner runtime.Pinner
+	defer pinner.Unpin()
+
+	rights := itemSet(&pinner, authorizationItem{name: cString(&pinner, rightExecute)})
+	environment := itemSet(&pinner, promptItem(&pinner))
+
+	var authorization uintptr
+	status := authorizationCreate(rights, environment,
+		flagDefaults|flagInteractionAllowed|flagPreAuthorize|flagExtendRights, &authorization)
+
+	switch status {
+	case errAuthorizationSuccess:
+		return authorization, nil
+	case errAuthorizationCanceled, errAuthorizationDenied:
+		return 0, ErrDeclined
+	case errAuthorizationInteractionNotAllowed:
+		// Nowhere to put a dialog, so there is nobody to ask: a launch daemon, or
+		// a session with no window server.
+		return 0, fmt.Errorf("%w: this session cannot show an authorization prompt", ErrUnavailable)
+	default:
+		return 0, fmt.Errorf("request %s: OSStatus %d", rightExecute, status)
+	}
+}
+
+// execute runs the tool with the right in hand and waits for it by reading the pipe
+// it is given until the tool closes it.
+//
+// AuthorizationExecuteWithPrivileges reports no exit status and does not say what
+// process it started, which is why the one-shot says so itself: what it prints is
+// the only evidence that the change was applied.
+func execute(ctx context.Context, authorization uintptr, self string, args []string) error {
+	var pinner runtime.Pinner
+	defer pinner.Unpin()
+
+	argv := make([]uintptr, 0, len(args)+1)
+	for _, arg := range args {
+		argv = append(argv, uintptr(unsafe.Pointer(cString(&pinner, arg))))
+	}
+	argv = append(argv, 0)
+	pinner.Pin(&argv[0])
+
+	var pipe uintptr
+	status := authorizationExecuteWithPrivileges(authorization, self, flagDefaults, &argv[0], &pipe)
+	switch status {
+	case errAuthorizationSuccess:
+	case errAuthorizationCanceled:
+		return ErrDeclined
+	case errAuthorizationToolExecuteFailure, errAuthorizationToolEnvironmentError:
+		// The right was granted and the tool still did not start. Nothing the user
+		// can do about it from here, so point them at the command instead.
+		return fmt.Errorf("%w: the system would not run %s elevated (OSStatus %d)", ErrUnavailable, self, status)
+	default:
+		return fmt.Errorf("run %s elevated: OSStatus %d", self, status)
+	}
+
+	out, err := readPipe(ctx, pipe)
+	if err != nil {
+		return err
+	}
+	return checkApplied(out)
+}
+
+// checkApplied reads the one-shot's report, which stands in for the exit status
+// there is no way to ask for here. A run that said nothing did not apply the
+// change, whatever else went on.
+func checkApplied(out string) error {
+	if !strings.Contains(out, AppliedMarker) {
+		return fmt.Errorf("elevated netbird did not report the change as applied: %s", firstLine(out))
+	}
+	return nil
+}
+
+// readPipe drains the tool's output, which ends when the tool exits and is
+// therefore also how we wait for it.
+func readPipe(ctx context.Context, pipe uintptr) (string, error) {
+	if pipe == 0 {
+		return "", nil
+	}
+	defer fclose(pipe)
+
+	fd := int(fileno(pipe))
+	if fd < 0 {
+		return "", nil
+	}
+
+	var out strings.Builder
+	buf := make([]byte, 4096)
+	for {
+		if err := ctx.Err(); err != nil {
+			return out.String(), err
+		}
+		n, err := syscall.Read(fd, buf)
+		if n > 0 {
+			out.Write(buf[:n])
+		}
+		switch {
+		case errors.Is(err, syscall.EINTR):
+			// A signal landed mid-read, which says nothing about the tool.
+			continue
+		case err != nil:
+			log.Debugf("read the elevated process's output: %v", err)
+			return out.String(), nil
+		case n <= 0:
+			// End of file: the tool closed the pipe, which is how it exiting
+			// reaches us.
+			return out.String(), nil
+		}
+	}
+}
+
+// itemSet builds an AuthorizationItemSet over items, pinned for the call.
+func itemSet(pinner *runtime.Pinner, items ...authorizationItem) *authorizationItemSet {
+	pinner.Pin(&items[0])
+	set := &authorizationItemSet{count: uint32(len(items)), items: &items[0]}
+	pinner.Pin(set)
+	return set
+}
+
+// promptItem is the environment entry carrying our sentence for the dialog.
+func promptItem(pinner *runtime.Pinner) authorizationItem {
+	value := []byte(promptText)
+	pinner.Pin(&value[0])
+	return authorizationItem{
+		name:        cString(pinner, promptKey),
+		valueLength: uintptr(len(value)),
+		value:       unsafe.Pointer(&value[0]),
+	}
+}
+
+// cString returns a NUL-terminated copy of s, pinned so the C side may hold it for
+// the duration of the call.
+func cString(pinner *runtime.Pinner, s string) *byte {
+	b := append([]byte(s), 0)
+	pinner.Pin(&b[0])
+	return &b[0]
+}

client/internal/elevate/run_darwin_test.go

@@ -0,0 +1,111 @@
+package elevate
+
+import (
+	"errors"
+	"runtime"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+// The framework has to load and the symbols have to resolve, or nothing else here
+// means anything.
+func TestSecurityFrameworkLoads(t *testing.T) {
+	require.NoError(t, load(), "Security.framework must open")
+
+	for name, fn := range map[string]any{
+		"AuthorizationCreate":                authorizationCreate,
+		"AuthorizationExecuteWithPrivileges": authorizationExecuteWithPrivileges,
+		"AuthorizationFree":                  authorizationFree,
+		"fileno":                             fileno,
+		"fclose":                             fclose,
+	} {
+		assert.NotNil(t, fn, "%s must resolve", name)
+	}
+}
+
+// A request with no interaction allowed exercises the whole call — the rights and
+// environment structs, and the OSStatus that comes back — without a dialog anybody
+// has to answer. What the system decides is its business; that it decides at all is
+// what this asserts.
+func TestAuthorizationCreateWithoutInteraction(t *testing.T) {
+	if err := load(); err != nil {
+		t.Skipf("Security.framework did not open: %v", err)
+	}
+
+	var pinner runtime.Pinner
+	defer pinner.Unpin()
+
+	rights := itemSet(&pinner, authorizationItem{name: cString(&pinner, rightExecute)})
+	environment := itemSet(&pinner, promptItem(&pinner))
+	require.EqualValues(t, 1, rights.count, "the rights struct layout must match the C one")
+
+	var authorization uintptr
+	status := authorizationCreate(rights, environment, flagDefaults|flagExtendRights, &authorization)
+
+	switch status {
+	case errAuthorizationSuccess:
+		// Credentials were already cached for this session.
+		authorizationFree(authorization, flagDestroyRights)
+	case errAuthorizationDenied, errAuthorizationInteractionNotAllowed:
+		// The expected answers when nobody may be asked.
+	default:
+		require.Failf(t, "unknown OSStatus", "AuthorizationCreate returned %d, want a status we recognise", status)
+	}
+}
+
+// Asking with a right nobody has must not be mistaken for a declined prompt: the
+// caller would report nothing at all.
+func TestAuthorizeUnknownRightIsNotDeclined(t *testing.T) {
+	if err := load(); err != nil {
+		t.Skipf("Security.framework did not open: %v", err)
+	}
+
+	var pinner runtime.Pinner
+	defer pinner.Unpin()
+
+	rights := itemSet(&pinner, authorizationItem{name: cString(&pinner, "io.netbird.right.that.does.not.exist")})
+
+	var authorization uintptr
+	status := authorizationCreate(rights, nil, flagDefaults|flagExtendRights, &authorization)
+	if status == errAuthorizationSuccess {
+		authorizationFree(authorization, flagDestroyRights)
+	}
+	assert.NotEqual(t, int32(errAuthorizationSuccess), status, "a right that does not exist must not be granted")
+}
+
+func TestMechanismAvailable(t *testing.T) {
+	assert.True(t, mechanismAvailable(), "the trampoline exists on every macOS")
+}
+
+// The one-shot's report is what stands in for an exit status here, so a run that
+// says nothing must not read as success.
+func TestCheckApplied(t *testing.T) {
+	require.NoError(t, checkApplied(AppliedMarker+"\n"), "the report the one-shot prints")
+	require.NoError(t, checkApplied("some warning\n"+AppliedMarker+"\n"), "the report after other output")
+
+	assert.Error(t, checkApplied(""), "a run that printed nothing did not apply the change")
+	assert.Error(t, checkApplied("dyld: library not loaded\n"), "output that is not the report")
+}
+
+// A panic out of the FFI layer has to reach the caller as "no mechanism", which is
+// the outcome that offers the user the command instead of taking the window down.
+func TestGuardTurnsAPanicIntoUnavailable(t *testing.T) {
+	err := guard("pretending to call something", func() error {
+		panic("purego: signature it cannot map")
+	})
+
+	require.ErrorIs(t, err, ErrUnavailable, "a panic must read as a missing mechanism")
+	assert.Contains(t, err.Error(), "pretending to call something", "what panicked")
+}
+
+// guard wraps every darwin path, so what a caller switches on has to survive it.
+func TestGuardPassesErrorsThrough(t *testing.T) {
+	sentinel := errors.New("the call itself failed")
+	assert.ErrorIs(t, guard("calling", func() error { return sentinel }), sentinel,
+		"the error it was given")
+	assert.ErrorIs(t, guard("calling", func() error { return ErrDeclined }), ErrDeclined,
+		"a declined prompt stays declined")
+	assert.NoError(t, guard("calling", func() error { return nil }), "a call that worked")
+}

client/internal/elevate/run_unix.go

@@ -0,0 +1,117 @@
+//go:build linux
+
+package elevate
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"io"
+	"os"
+	"os/exec"
+	"strings"
+)
+
+// pkexec exit codes that are about the authorization rather than about the program
+// we asked it to run. The manual page reserves both.
+const (
+	// exitDismissed is returned when the user dismissed the authentication
+	// dialog.
+	exitDismissed = 126
+	// exitNotAuthorized is returned when the authorization was not obtained. That
+	// covers the user saying no as well as pkexec having had nobody to ask: see
+	// noAgentMarkers.
+	exitNotAuthorized = 127
+)
+
+// exitNotAuthorized covers three different endings that only pkexec's own words
+// tell apart, so they are matched here. Read with LC_ALL=C so the words are the
+// ones written below.
+//
+// refusedMarker is a refusal: the user said no, gave up on the password, or holds
+// an account that may not elevate at all.
+const refusedMarker = "Not authorized"
+
+// noAgentMarkers say pkexec had no way to ask: no agent registered for the
+// session, and no controlling terminal for the textual agent it falls back to.
+var noAgentMarkers = []string{"authentication agent", "controlling terminal"}
+
+// run asks polkit to run self as root. pkexec hands the request to the session's
+// polkit agent, which is what prompts and what collects any password; we see only
+// its verdict.
+//
+// The environment is otherwise deliberately not passed through: pkexec clears it
+// bar a small allowlist, and the one-shot needs nothing from it.
+func run(ctx context.Context, self string, args []string) error {
+	pkexec, err := exec.LookPath("pkexec")
+	if err != nil {
+		return fmt.Errorf("%w: pkexec is not installed", ErrUnavailable)
+	}
+
+	cmd := exec.CommandContext(ctx, pkexec, append([]string{self}, args...)...)
+	// C locale so pkexec's own diagnostics are the ones noAgentMarkers knows.
+	cmd.Env = append(os.Environ(), "LC_ALL=C")
+	var stderr strings.Builder
+	cmd.Stderr = &stderr
+	// The one-shot reports itself on stdout for macOS's sake, where there is no
+	// exit status to read. Here there is one, so that line is noise.
+	cmd.Stdout = io.Discard
+
+	err = cmd.Run()
+	if err == nil {
+		return nil
+	}
+
+	var exitErr *exec.ExitError
+	if !errors.As(err, &exitErr) {
+		return fmt.Errorf("run pkexec: %w", err)
+	}
+
+	// Matched against everything pkexec said, reported as one line: a complaint
+	// that is not the first thing printed still has to be recognised, and reading
+	// it as a refusal would swallow it.
+	full := stderr.String()
+	out := firstLine(full)
+
+	switch exitErr.ExitCode() {
+	case exitDismissed:
+		return ErrDeclined
+	case exitNotAuthorized:
+		return notAuthorized(full, out)
+	default:
+		return fmt.Errorf("elevated netbird exited with %d: %s", exitErr.ExitCode(), out)
+	}
+}
+
+// notAuthorized sorts out the three endings pkexec reports as exitNotAuthorized.
+//
+// It also returns that code when the authorization succeeded and it then could
+// not run the program, so a refusal has to be recognised rather than assumed:
+// reading every one of these as "the user said no" would revert the control in
+// silence on a host where elevation is broken.
+func notAuthorized(full, out string) error {
+	switch {
+	case hasAny(full, noAgentMarkers):
+		return fmt.Errorf("%w: polkit had no way to ask: %s", ErrUnavailable, out)
+	case out == noOutput, strings.Contains(full, refusedMarker):
+		// The user said no, which needs no message; that an account barred from
+		// elevating altogether lands here too is why the reason is kept.
+		return fmt.Errorf("%w: %s", ErrDeclined, out)
+	default:
+		return fmt.Errorf("pkexec could not run elevated netbird: %s", out)
+	}
+}
+
+func hasAny(s string, markers []string) bool {
+	for _, marker := range markers {
+		if strings.Contains(s, marker) {
+			return true
+		}
+	}
+	return false
+}
+
+func mechanismAvailable() bool {
+	_, err := exec.LookPath("pkexec")
+	return err == nil
+}

client/internal/elevate/run_unix_test.go

@@ -0,0 +1,110 @@
+//go:build linux
+
+package elevate
+
+import (
+	"context"
+	"fmt"
+	"os"
+	"path/filepath"
+	"strings"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+// fakePkexec puts a pkexec on PATH that exits with the given code, so the
+// mapping from polkit's exit codes onto our errors can be exercised without a
+// polkit agent.
+func fakePkexec(t *testing.T, exitCode int, stderr string) {
+	t.Helper()
+
+	dir := t.TempDir()
+	script := fmt.Sprintf("#!/bin/sh\necho %s >&2\nexit %d\n", shellQuote(stderr), exitCode)
+	require.NoError(t, os.WriteFile(filepath.Join(dir, "pkexec"), []byte(script), 0o700), "write the fake pkexec")
+	t.Setenv("PATH", dir)
+}
+
+func shellQuote(s string) string {
+	return "'" + strings.ReplaceAll(s, "'", `'\''`) + "'"
+}
+
+func TestRunMapsPkexecExitCodes(t *testing.T) {
+	tests := []struct {
+		name     string
+		exitCode int
+		stderr   string
+		wantErr  error
+	}{
+		{name: "applied", exitCode: 0},
+		{
+			name:     "dialog dismissed",
+			exitCode: exitDismissed,
+			stderr:   "Error executing command as another user: Request dismissed",
+			wantErr:  ErrDeclined,
+		},
+		{
+			// What a graphical agent reports for a cancelled prompt. Not a
+			// failure: the user was asked and answered.
+			name:     "prompt cancelled",
+			exitCode: exitNotAuthorized,
+			stderr:   "Error executing command as another user: Not authorized",
+			wantErr:  ErrDeclined,
+		},
+		{
+			// The same status, but pkexec never got to ask anybody.
+			name:     "no agent and no terminal to fall back on",
+			exitCode: exitNotAuthorized,
+			stderr:   "Error creating textual authentication agent: Error opening current controlling terminal for the process (`/dev/tty'): No such device or address",
+			wantErr:  ErrUnavailable,
+		},
+		{
+			// And the same status again once the authorization succeeded and
+			// pkexec could not run what it had been authorized to run. Reading
+			// that as a refusal would revert the control in silence on a host
+			// where elevation is broken.
+			name:     "authorized but not runnable",
+			exitCode: exitNotAuthorized,
+			stderr:   "Error executing command as another user: No such file or directory",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			fakePkexec(t, tt.exitCode, tt.stderr)
+
+			err := run(context.Background(), "/nonexistent/netbird-ui", []string{"--flag"})
+			switch {
+			case tt.wantErr != nil:
+				require.ErrorIs(t, err, tt.wantErr, "exit %d said %q", tt.exitCode, tt.stderr)
+			case tt.exitCode == 0:
+				require.NoError(t, err, "a pkexec that exited cleanly applied the change")
+			default:
+				require.Error(t, err, "exit %d said %q", tt.exitCode, tt.stderr)
+				assert.NotErrorIs(t, err, ErrDeclined, "not the user's answer")
+				assert.NotErrorIs(t, err, ErrUnavailable, "not a missing mechanism")
+			}
+		})
+	}
+}
+
+// An exit code that is not polkit's is the one-shot's own failure, and has to
+// stay distinguishable from a declined prompt: the caller reports it.
+func TestRunReportsOneShotFailure(t *testing.T) {
+	fakePkexec(t, 3, "the one-shot said no")
+
+	err := run(context.Background(), "/nonexistent/netbird-ui", nil)
+
+	require.Error(t, err, "a one-shot that failed is not a prompt that was answered")
+	assert.NotErrorIs(t, err, ErrDeclined, "not the user's answer")
+	assert.NotErrorIs(t, err, ErrUnavailable, "not a missing mechanism")
+}
+
+func TestRunWithoutPkexecIsUnavailable(t *testing.T) {
+	t.Setenv("PATH", t.TempDir())
+
+	err := run(context.Background(), "/nonexistent/netbird-ui", nil)
+	require.ErrorIs(t, err, ErrUnavailable, "no pkexec means no mechanism")
+	assert.False(t, mechanismAvailable(), "mechanismAvailable without pkexec on PATH")
+}

client/internal/elevate/run_unsupported.go

@@ -0,0 +1,19 @@
+//go:build !windows && !darwin && !linux
+
+package elevate
+
+import "context"
+
+// run reports that this platform has no elevation prompt to drive.
+//
+// The desktop app is the only caller and is not built for any of these: mobile
+// and WASM have no local user to ask, and the FreeBSD client ships without a UI.
+// pkexec would be the mechanism there, and run_unix.go is what to widen if that
+// changes.
+func run(context.Context, string, []string) error {
+	return ErrUnavailable
+}
+
+func mechanismAvailable() bool {
+	return false
+}

client/internal/elevate/run_windows.go

@@ -0,0 +1,187 @@
+package elevate
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"runtime"
+	"unsafe"
+
+	log "github.com/sirupsen/logrus"
+	"golang.org/x/sys/windows"
+)
+
+const (
+	// seeMaskNoCloseProcess keeps the started process's handle open in
+	// hProcess so we can wait for it.
+	seeMaskNoCloseProcess = 0x00000040
+	// seeMaskNoAsync makes ShellExecuteExW finish its work before returning,
+	// which it must when the calling thread does not pump messages.
+	seeMaskNoAsync = 0x00000100
+	// seeMaskFlagNoUI suppresses the shell's own error dialogs; the UAC consent
+	// dialog is not one of them and still appears.
+	seeMaskFlagNoUI = 0x00000400
+
+	// swHide: the one-shot has no window to show.
+	swHide = 0
+)
+
+// shellExecuteInfoW mirrors SHELLEXECUTEINFOW. The field order and Go's own
+// padding match the C layout on both 386 and amd64.
+type shellExecuteInfoW struct {
+	cbSize         uint32
+	fMask          uint32
+	hwnd           windows.HWND
+	lpVerb         *uint16
+	lpFile         *uint16
+	lpParameters   *uint16
+	lpDirectory    *uint16
+	nShow          int32
+	hInstApp       windows.Handle
+	lpIDList       uintptr
+	lpClass        *uint16
+	hkeyClass      windows.Handle
+	dwHotKey       uint32
+	hIconOrMonitor windows.Handle
+	hProcess       windows.Handle
+}
+
+var (
+	shell32            = windows.NewLazySystemDLL("shell32.dll")
+	procShellExecuteEx = shell32.NewProc("ShellExecuteExW")
+)
+
+// run starts self elevated with the "runas" verb, which is what raises the UAC
+// consent dialog, and waits for it to finish. Windows decides whether consent is
+// enough or an administrator's credentials are needed, and collects them itself.
+func run(ctx context.Context, self string, args []string) error {
+	verb, err := windows.UTF16PtrFromString("runas")
+	if err != nil {
+		return fmt.Errorf("encode verb: %w", err)
+	}
+	file, err := windows.UTF16PtrFromString(self)
+	if err != nil {
+		return fmt.Errorf("encode %s: %w", self, err)
+	}
+	params, err := windows.UTF16PtrFromString(windows.ComposeCommandLine(args))
+	if err != nil {
+		return fmt.Errorf("encode arguments: %w", err)
+	}
+
+	info := shellExecuteInfoW{
+		fMask:        seeMaskNoCloseProcess | seeMaskNoAsync | seeMaskFlagNoUI,
+		hwnd:         ownerWindow(),
+		lpVerb:       verb,
+		lpFile:       file,
+		lpParameters: params,
+		nShow:        swHide,
+	}
+	info.cbSize = uint32(unsafe.Sizeof(info))
+
+	process, err := shellExecute(&info)
+	if err != nil {
+		return err
+	}
+	defer func() {
+		if err := windows.CloseHandle(process); err != nil {
+			log.Debugf("close elevated process handle: %v", err)
+		}
+	}()
+
+	return waitForProcess(ctx, process)
+}
+
+// shellExecute performs the call itself. ShellExecuteExW wants COM initialised on
+// the calling thread, so the goroutine is pinned to one for the duration and COM
+// is set up on it; an "already initialised, different mode" answer is fine,
+// because then somebody else has done it for us.
+func shellExecute(info *shellExecuteInfoW) (windows.Handle, error) {
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
+	switch err := windows.CoInitializeEx(0, windows.COINIT_APARTMENTTHREADED); {
+	case err == nil, isHResult(err, windows.S_FALSE):
+		// Ours, or already initialised in the same mode: either way this call
+		// counts and has to be balanced.
+		defer windows.CoUninitialize()
+	case isHResult(err, windows.RPC_E_CHANGED_MODE):
+		// The thread is already in the other apartment model. ShellExecuteExW
+		// works there too, and there is nothing of ours to balance.
+	default:
+		return 0, fmt.Errorf("initialise COM: %w", err)
+	}
+
+	ret, _, lastErr := procShellExecuteEx.Call(uintptr(unsafe.Pointer(info)))
+	if ret != 0 {
+		return info.hProcess, nil
+	}
+
+	if errors.Is(lastErr, windows.ERROR_CANCELLED) {
+		return 0, ErrDeclined
+	}
+	return 0, fmt.Errorf("run elevated: %w", lastErr)
+}
+
+// ownerWindow returns this process's foreground window, and 0 when the window in
+// front belongs to somebody else or cannot be attributed. ShellExecuteExW takes it
+// as the parent for the UI it raises, which is what keeps the consent dialog in
+// front of the window the user was just clicking in instead of behind it. It is
+// also what a remote-desktop session needs to place the dialog at all when the
+// secure desktop is switched off.
+func ownerWindow() windows.HWND {
+	hwnd := windows.GetForegroundWindow()
+	if hwnd == 0 {
+		return 0
+	}
+
+	var pid uint32
+	if _, err := windows.GetWindowThreadProcessId(hwnd, &pid); err != nil {
+		log.Debugf("cannot attribute the foreground window, raising the prompt without an owner: %v", err)
+		return 0
+	}
+	if pid != windows.GetCurrentProcessId() {
+		return 0
+	}
+	return hwnd
+}
+
+// isHResult reports whether err carries the given HRESULT. CoInitializeEx
+// returns its HRESULT as an Errno, so the comparison is on the raw value.
+func isHResult(err error, hresult windows.Handle) bool {
+	var errno windows.Errno
+	return errors.As(err, &errno) && uintptr(errno) == uintptr(hresult)
+}
+
+func waitForProcess(ctx context.Context, process windows.Handle) error {
+	// The wait is interruptible so a cancelled context stops us waiting on a
+	// consent dialog nobody is going to answer. The elevated process is not
+	// ours to kill, and it either applies the change or does not.
+	for {
+		event, err := windows.WaitForSingleObject(process, 250)
+		if err != nil {
+			return fmt.Errorf("wait for the elevated process: %w", err)
+		}
+		if event == uint32(windows.WAIT_OBJECT_0) {
+			break
+		}
+		if err := ctx.Err(); err != nil {
+			return err
+		}
+	}
+
+	var code uint32
+	if err := windows.GetExitCodeProcess(process, &code); err != nil {
+		return fmt.Errorf("read the elevated process's exit code: %w", err)
+	}
+	if code != 0 {
+		return fmt.Errorf("elevated netbird exited with %d", code)
+	}
+	return nil
+}
+
+// mechanismAvailable is true on Windows: UAC prompts for consent when the user
+// is an administrator and for an administrator's credentials when they are not,
+// so there is always something to ask.
+func mechanismAvailable() bool {
+	return true
+}

client/internal/elevate/trusted.go

@@ -0,0 +1,40 @@
+package elevate
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+)
+
+// trustedSelf returns the path of this executable, provided it is one we are
+// willing to have run as root.
+//
+// The check is what keeps elevation from becoming a way to launder someone
+// else's code into a root process: the user consents to NetBird being elevated,
+// having been shown NetBird's name, so what runs must be the file NetBird was
+// installed as and not something a third party could have swapped for it. An
+// executable only its owner can write is that; anything wider is refused, and
+// the caller falls back to showing the command instead.
+//
+// The owner writing to their own executable is not part of that threat: code
+// running as the user can already prompt them for anything, and could just as
+// well ask them to run the command by hand. What matters is that no *other*
+// unprivileged account can reach it.
+func trustedSelf() (string, error) {
+	exe, err := os.Executable()
+	if err != nil {
+		return "", fmt.Errorf("locate this executable: %w", err)
+	}
+
+	// Resolve symlinks so the checks below apply to the file that would actually
+	// be executed, not to a link somebody else may control.
+	resolved, err := filepath.EvalSymlinks(exe)
+	if err != nil {
+		return "", fmt.Errorf("resolve %s: %w", exe, err)
+	}
+
+	if err := checkOnlyOwnerWritable(resolved); err != nil {
+		return "", fmt.Errorf("%w: %s cannot be trusted to run as root: %w", ErrUnavailable, resolved, err)
+	}
+	return resolved, nil
+}

client/internal/elevate/trusted_group_darwin.go

@@ -0,0 +1,10 @@
+package elevate
+
+// adminWriteGIDs are the groups whose write access to an executable does not
+// widen who could authorize elevating it.
+//
+// macOS installs applications as root:admin, mode 0775, /Applications included,
+// so requiring owner-only write would reject every normal install. Group admin
+// (gid 80) is exactly the set of accounts that can answer the authentication
+// dialog, so its write access grants nothing the prompt would not.
+var adminWriteGIDs = []uint32{0, 80}

client/internal/elevate/trusted_group_unix.go

@@ -0,0 +1,9 @@
+//go:build !windows && !darwin
+
+package elevate
+
+// adminWriteGIDs are the groups whose write access to an executable does not
+// widen who could authorize elevating it. Only root's own group qualifies here:
+// a distribution installs into root-owned directories, and there is no
+// system-wide administrators group that both writes them and answers polkit.
+var adminWriteGIDs = []uint32{0}

client/internal/elevate/trusted_unix.go

@@ -0,0 +1,119 @@
+//go:build !windows
+
+package elevate
+
+import (
+	"errors"
+	"fmt"
+	"os"
+	"path/filepath"
+	"slices"
+	"strconv"
+	"syscall"
+
+	log "github.com/sirupsen/logrus"
+
+	"github.com/netbirdio/netbird/client/internal/getent"
+)
+
+// checkOnlyOwnerWritable reports an error unless path, and every directory leading
+// to it, is owned by either root or this user and writable by nobody who could not
+// already act as its owner. A writable directory is as good as a writable file,
+// since anything in it can be replaced, so the whole chain is checked.
+func checkOnlyOwnerWritable(path string) error {
+	self := uint32(os.Getuid())
+
+	for dir := path; ; dir = filepath.Dir(dir) {
+		info, err := os.Lstat(dir)
+		if err != nil {
+			return fmt.Errorf("stat %s: %w", dir, err)
+		}
+
+		stat, ok := info.Sys().(*syscall.Stat_t)
+		if !ok {
+			return errors.New("file ownership is unavailable on this platform")
+		}
+		if stat.Uid != 0 && stat.Uid != self {
+			return fmt.Errorf("%s is owned by uid %d, neither root nor this user", dir, stat.Uid)
+		}
+
+		if err := checkWriteBits(dir, info, stat.Uid, stat.Gid); err != nil {
+			return err
+		}
+
+		if parent := filepath.Dir(dir); parent == dir {
+			return nil
+		}
+	}
+}
+
+func checkWriteBits(path string, info os.FileInfo, uid, gid uint32) error {
+	// On a directory the sticky bit stands in for the write bits: whoever may
+	// write there still cannot replace an entry they do not own, which is the
+	// only thing that would matter to us. /tmp is the usual example.
+	sticky := info.IsDir() && info.Mode()&os.ModeSticky != 0
+
+	return writeBitsAllow(path, info.Mode().Perm(), sticky, groupWriteAllowed(uid, gid))
+}
+
+// writeBitsAllow decides on the permission bits alone, given whether the group's
+// write access has been vouched for.
+func writeBitsAllow(path string, perm os.FileMode, sticky, groupAllowed bool) error {
+	if sticky {
+		return nil
+	}
+	if perm&0o020 != 0 && !groupAllowed {
+		return fmt.Errorf("%s is writable by a group with members other than its owner (%v)", path, perm)
+	}
+	if perm&0o002 != 0 {
+		return fmt.Errorf("%s is world-writable (%v)", path, perm)
+	}
+	return nil
+}
+
+// groupWriteAllowed reports whether a group's write access to a file owned by uid
+// puts it in reach of anyone who could not already act as that owner.
+//
+// Two ways it does not. A group in adminWriteGIDs holds the accounts that can
+// answer the elevation prompt anyway. And a user private group is how Debian,
+// Ubuntu and Fedora ship: their umask of 002 makes a home directory and
+// everything built in it group-writable, so refusing that would refuse every
+// build not installed from a package.
+func groupWriteAllowed(uid, gid uint32) bool {
+	if slices.Contains(adminWriteGIDs, gid) {
+		return true
+	}
+
+	group, err := getent.LookupGroupID(strconv.FormatUint(uint64(gid), 10))
+	if err != nil {
+		log.Debugf("cannot look up group %d, treating it as shared: %v", gid, err)
+		return false
+	}
+	owner, err := getent.LookupUserID(strconv.FormatUint(uint64(uid), 10))
+	if err != nil {
+		log.Debugf("cannot look up uid %d, treating its group as shared: %v", uid, err)
+		return false
+	}
+
+	if group.Name != owner.Username {
+		return false
+	}
+	return !groupHasOtherMembers(group.Name, owner.Username)
+}
+
+// groupHasOtherMembers reports whether the group lists a member besides owner.
+//
+// Sharing the owner's name is what a user private group is recognised by, and it
+// says nothing about who is in it: a group that has since gained a member is
+// still named that way, and that member can write whatever the group can. So the
+// membership is read rather than assumed. A group whose members cannot be
+// listed, because no source on this host describes it, is treated as shared:
+// the name alone cannot vouch for who writes through it.
+func groupHasOtherMembers(name, owner string) bool {
+	members, err := getent.GroupMembers(name)
+	if err != nil {
+		log.Debugf("cannot list the members of group %q, treating it as shared: %v", name, err)
+		return true
+	}
+	return slices.ContainsFunc(members, func(member string) bool { return member != owner })
+}

client/internal/elevate/trusted_unix_test.go

@@ -0,0 +1,148 @@
+//go:build !windows
+
+package elevate
+
+import (
+	"os"
+	"os/user"
+	"path/filepath"
+	"strconv"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+// ownerOnlyDir is t.TempDir() with the write bits tightened. testing creates its
+// numbered directory with 0777 minus the umask, so under the common 002 umask it
+// is group-writable and would fail the check under test on its own.
+func ownerOnlyDir(t *testing.T) string {
+	t.Helper()
+	dir := t.TempDir()
+	require.NoError(t, os.Chmod(dir, 0o755), "tighten the temporary directory")
+	return dir
+}
+
+// writeExecutable creates a plain executable file, the shape trustedSelf checks.
+func writeExecutable(t *testing.T, dir string) string {
+	t.Helper()
+	path := filepath.Join(dir, "netbird-ui")
+	require.NoError(t, os.WriteFile(path, []byte("#!/bin/sh\n"), 0o755), "write the executable")
+	require.NoError(t, os.Chmod(path, 0o755), "set the executable's mode")
+	return path
+}
+
+func TestCheckOnlyOwnerWritableAcceptsOwnerOnly(t *testing.T) {
+	err := checkOnlyOwnerWritable(writeExecutable(t, ownerOnlyDir(t)))
+	assert.NoError(t, err, "an owner-only writable executable is trustworthy")
+}
+
+func TestCheckOnlyOwnerWritableRejectsWorldWritableFile(t *testing.T) {
+	path := writeExecutable(t, ownerOnlyDir(t))
+	require.NoError(t, os.Chmod(path, 0o777), "make the executable world-writable")
+
+	assert.Error(t, checkOnlyOwnerWritable(path), "a world-writable executable must be refused")
+}
+
+// The permission policy on its own, without a filesystem to arrange: whether the
+// group has been vouched for is the only thing that makes group write acceptable.
+func TestWriteBitsAllow(t *testing.T) {
+	tests := []struct {
+		name         string
+		perm         os.FileMode
+		sticky       bool
+		groupAllowed bool
+		wantErr      bool
+	}{
+		{name: "owner only", perm: 0o755},
+		{name: "group write in a private group", perm: 0o775, groupAllowed: true},
+		{name: "group write in a shared group", perm: 0o775, wantErr: true},
+		{name: "world write", perm: 0o777, groupAllowed: true, wantErr: true},
+		{name: "world write on a sticky directory", perm: 0o777, sticky: true},
+		{name: "group write on a sticky directory", perm: 0o775, sticky: true},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			err := writeBitsAllow("/path", tt.perm, tt.sticky, tt.groupAllowed)
+			if tt.wantErr {
+				assert.Error(t, err, "perm %v, sticky %v, group allowed %v", tt.perm, tt.sticky, tt.groupAllowed)
+				return
+			}
+			assert.NoError(t, err, "perm %v, sticky %v, group allowed %v", tt.perm, tt.sticky, tt.groupAllowed)
+		})
+	}
+}
+
+// A build under a home directory on a distribution with a 002 umask, which is what
+// a locally built or tarball-installed binary looks like. Its group has no members
+// but its owner, so it is as good as owner-only.
+//
+// Whether this host is such a distribution is read from the environment rather than
+// from groupWriteAllowed: asking the function under test whether to run would let
+// it skip its own coverage away if it regressed to refusing everything.
+func TestCheckOnlyOwnerWritableAcceptsOwnPrivateGroup(t *testing.T) {
+	requirePrivatePrimaryGroup(t)
+
+	dir := ownerOnlyDir(t)
+	path := writeExecutable(t, dir)
+	require.NoError(t, os.Chmod(dir, 0o775), "make the directory group-writable")
+	require.NoError(t, os.Chmod(path, 0o775), "make the executable group-writable")
+
+	err := checkOnlyOwnerWritable(path)
+	assert.NoError(t, err, "group write in the owner's own private group reaches nobody else")
+}
+
+// A group whose membership no source can answer for is treated as shared: the
+// private-group allowance must not stand on a name nobody can vouch for. The
+// membership listing itself lives in the getent package and is tested there.
+func TestGroupHasOtherMembersRejectsAnUnknownGroup(t *testing.T) {
+	assert.True(t, groupHasOtherMembers("nonexistent_group_xyzzy_12345", "vma"),
+		"a group no source describes")
+}
+
+// A writable directory is as good as a writable file: whoever can write the
+// directory can put a different binary at the same path.
+func TestCheckOnlyOwnerWritableRejectsWritableDirectory(t *testing.T) {
+	dir := filepath.Join(ownerOnlyDir(t), "bin")
+	require.NoError(t, os.Mkdir(dir, 0o755), "create the directory")
+	path := writeExecutable(t, dir)
+	require.NoError(t, os.Chmod(dir, 0o777), "make the directory world-writable")
+
+	assert.Error(t, checkOnlyOwnerWritable(path), "an executable in a world-writable directory must be refused")
+}
+
+// A sticky world-writable directory is exempt: the sticky bit is what stops one
+// user replacing another's entries. /tmp is why this matters.
+func TestCheckOnlyOwnerWritableAcceptsStickyDirectory(t *testing.T) {
+	dir := filepath.Join(ownerOnlyDir(t), "sticky")
+	require.NoError(t, os.Mkdir(dir, 0o755), "create the directory")
+	path := writeExecutable(t, dir)
+	require.NoError(t, os.Chmod(dir, 0o777|os.ModeSticky), "make the directory sticky and world-writable")
+
+	err := checkOnlyOwnerWritable(path)
+	assert.NoError(t, err, "the sticky bit stops another user replacing the executable")
+}
+
+func TestCheckOnlyOwnerWritableRejectsMissingFile(t *testing.T) {
+	err := checkOnlyOwnerWritable(filepath.Join(ownerOnlyDir(t), "absent"))
+	assert.Error(t, err, "an executable that is not there must be refused")
+}
+
+// requirePrivatePrimaryGroup skips unless this user's primary group is their own,
+// which is what the user-private-group allowance is about.
+func requirePrivatePrimaryGroup(t *testing.T) {
+	t.Helper()
+
+	self, err := user.Current()
+	require.NoError(t, err, "look up the test user")
+	group, err := user.LookupGroupId(strconv.Itoa(os.Getgid()))
+	require.NoError(t, err, "look up the test user's primary group")
+
+	if group.Name != self.Username {
+		t.Skipf("the test user's primary group is %q, not their own, so there is nothing to assert here", group.Name)
+	}
+	if groupHasOtherMembers(group.Name, self.Username) {
+		t.Skipf("group %q has other members, so it is not a private group", group.Name)
+	}
+}

client/internal/elevate/trusted_windows.go

@@ -0,0 +1,215 @@
+package elevate
+
+import (
+	"errors"
+	"fmt"
+	"path/filepath"
+	"slices"
+	"unsafe"
+
+	"golang.org/x/sys/windows"
+)
+
+const (
+	// fileDeleteChild is FILE_DELETE_CHILD, which x/sys does not define: the
+	// right to delete an entry of a directory without holding DELETE on it.
+	fileDeleteChild = 0x00000040
+
+	// accessAllowedCallbackACEType is an allow ACE with a condition appended to
+	// the ACCESS_ALLOWED_ACE layout, so its trustee is still at SidStart.
+	accessAllowedCallbackACEType = 0x9
+
+	// The allow ACE types that carry object GUIDs ahead of the trustee, so the
+	// SID is not at SidStart. They occur on directory-service objects rather
+	// than files, and are refused rather than skipped: see aceTrustee.
+	accessAllowedObjectACEType         = 0x5
+	accessAllowedCallbackObjectACEType = 0xB
+)
+
+// fileWriteAccess are the rights that let a trustee rewrite or replace a file,
+// or take it over and then do so.
+const fileWriteAccess = windows.FILE_WRITE_DATA | windows.FILE_APPEND_DATA |
+	windows.DELETE | windows.WRITE_DAC | windows.WRITE_OWNER |
+	windows.GENERIC_WRITE | windows.GENERIC_ALL
+
+// dirWriteAccess are the rights over a directory that let a trustee replace an
+// entry somebody else owns. Creating a new entry is not one of them, which is
+// what the Unix sticky bit says in one bit: the root of every volume grants
+// BUILTIN\Users the right to add directories under it, and that reaches nothing
+// already there.
+const dirWriteAccess = fileDeleteChild | windows.DELETE |
+	windows.WRITE_DAC | windows.WRITE_OWNER | windows.GENERIC_ALL
+
+// trustedInstallerSID owns much of what Windows itself installs. x/sys has no
+// well-known constant for it.
+const trustedInstallerSID = "S-1-5-80-956008885-3418522649-1831038044-1853292631-2271478464"
+
+// checkOnlyOwnerWritable reports an error unless path, and every directory
+// leading to it, is owned by an account that can elevate (or by this user) and
+// grants write access to nobody else. A writable directory is as good as a
+// writable file, since an entry in it can be replaced, so the whole chain is
+// checked.
+func checkOnlyOwnerWritable(path string) error {
+	owners, err := trustedOwners()
+	if err != nil {
+		return err
+	}
+	writers, err := trustedWriters(owners)
+	if err != nil {
+		return err
+	}
+
+	writeAccess := windows.ACCESS_MASK(fileWriteAccess)
+	for target := path; ; target = filepath.Dir(target) {
+		if err := checkSecurity(target, writeAccess, owners, writers); err != nil {
+			return err
+		}
+		if parent := filepath.Dir(target); parent == target {
+			return nil
+		}
+		writeAccess = dirWriteAccess
+	}
+}
+
+// trustedOwners are the accounts we accept as the owner of the executable and of
+// the directories above it: the ones that can already answer the UAC prompt,
+// plus this user, whose own executable is theirs to write. Code running as the
+// user could prompt them for anything anyway; what matters is that no *other*
+// unprivileged account can reach it.
+func trustedOwners() ([]*windows.SID, error) {
+	self, err := currentUserSID()
+	if err != nil {
+		return nil, err
+	}
+
+	owners := []*windows.SID{self}
+	for _, wellKnown := range []windows.WELL_KNOWN_SID_TYPE{
+		windows.WinLocalSystemSid,
+		windows.WinBuiltinAdministratorsSid,
+	} {
+		sid, err := windows.CreateWellKnownSid(wellKnown)
+		if err != nil {
+			return nil, fmt.Errorf("build well-known SID %d: %w", wellKnown, err)
+		}
+		owners = append(owners, sid)
+	}
+
+	installer, err := windows.StringToSid(trustedInstallerSID)
+	if err != nil {
+		return nil, fmt.Errorf("parse TrustedInstaller SID: %w", err)
+	}
+	return append(owners, installer), nil
+}
+
+// trustedWriters are the trustees whose write access does not widen who could
+// decide what runs behind the prompt. The owners, and CREATOR OWNER, which
+// resolves to the object's owner and is therefore already vetted.
+func trustedWriters(owners []*windows.SID) ([]*windows.SID, error) {
+	creatorOwner, err := windows.CreateWellKnownSid(windows.WinCreatorOwnerSid)
+	if err != nil {
+		return nil, fmt.Errorf("build the CREATOR OWNER SID: %w", err)
+	}
+	return append(slices.Clone(owners), creatorOwner), nil
+}
+
+func checkSecurity(path string, writeAccess windows.ACCESS_MASK, owners, writers []*windows.SID) error {
+	sd, err := windows.GetNamedSecurityInfo(path, windows.SE_FILE_OBJECT,
+		windows.OWNER_SECURITY_INFORMATION|windows.DACL_SECURITY_INFORMATION)
+	if err != nil {
+		return fmt.Errorf("read security descriptor of %s: %w", path, err)
+	}
+
+	owner, _, err := sd.Owner()
+	if err != nil {
+		return fmt.Errorf("read owner of %s: %w", path, err)
+	}
+	if !containsSID(owners, owner) {
+		return fmt.Errorf("%s is owned by %s, which is neither this user nor an account that can elevate", path, owner)
+	}
+
+	dacl, _, err := sd.DACL()
+	if err != nil {
+		return fmt.Errorf("read DACL of %s: %w", path, err)
+	}
+	// A NULL DACL grants everyone everything; only an absent security
+	// descriptor would have got us here without one, and neither is trustworthy.
+	if dacl == nil {
+		return fmt.Errorf("%s has no DACL, so it grants write access to everyone", path)
+	}
+
+	return checkDACL(path, dacl, writeAccess, writers)
+}
+
+// checkDACL refuses an ACL that grants write access to a trustee outside
+// writers.
+//
+// An allowlist, because the trustees that must not have it cannot be listed: an
+// ACE naming an ordinary user account hands that account the same power as one
+// naming Everyone, and only the accounts that may hold it are knowable.
+func checkDACL(path string, dacl *windows.ACL, writeAccess windows.ACCESS_MASK, writers []*windows.SID) error {
+	for i := uint32(0); i < uint32(dacl.AceCount); i++ {
+		var ace *windows.ACCESS_ALLOWED_ACE
+		if err := windows.GetAce(dacl, i, &ace); err != nil {
+			return fmt.Errorf("read ACE %d of %s: %w", i, path, err)
+		}
+		// An inherit-only ACE says what children of this object get, not what
+		// this object grants.
+		if ace.Header.AceFlags&windows.INHERIT_ONLY_ACE != 0 {
+			continue
+		}
+		if ace.Mask&writeAccess == 0 {
+			continue
+		}
+		// Only an allow ACE grants anything; a deny ACE narrows what one gave.
+		if !isAllowACE(ace.Header.AceType) {
+			continue
+		}
+
+		trustee, err := aceTrustee(ace)
+		if err != nil {
+			return fmt.Errorf("read the trustee of ACE %d of %s: %w", i, path, err)
+		}
+		if !containsSID(writers, trustee) {
+			return fmt.Errorf("%s grants write access to %s", path, trustee)
+		}
+	}
+	return nil
+}
+
+// isAllowACE reports whether an ACE type grants rights, rather than denying,
+// auditing or labelling them.
+func isAllowACE(aceType uint8) bool {
+	switch aceType {
+	case windows.ACCESS_ALLOWED_ACE_TYPE, accessAllowedCallbackACEType,
+		accessAllowedObjectACEType, accessAllowedCallbackObjectACEType:
+		return true
+	default:
+		return false
+	}
+}
+
+// aceTrustee returns who an allow ACE grants its rights to. An ACE whose trustee
+// cannot be located is an error rather than something to skip past: being unable
+// to read who is being given write access is a refusal.
+func aceTrustee(ace *windows.ACCESS_ALLOWED_ACE) (*windows.SID, error) {
+	switch ace.Header.AceType {
+	case windows.ACCESS_ALLOWED_ACE_TYPE, accessAllowedCallbackACEType:
+		//nolint:gosec // SidStart is the first uint32 of the variable-length SID that follows the ACE header.
+		return (*windows.SID)(unsafe.Pointer(&ace.SidStart)), nil
+	default:
+		return nil, errors.New("an object-type allow ACE does not carry its trustee where we can read it")
+	}
+}
+
+func containsSID(sids []*windows.SID, sid *windows.SID) bool {
+	return slices.ContainsFunc(sids, sid.Equals)
+}
+
+func currentUserSID() (*windows.SID, error) {
+	token := windows.GetCurrentProcessToken()
+	user, err := token.GetTokenUser()
+	if err != nil {
+		return nil, fmt.Errorf("read this process's user: %w", err)
+	}
+	return user.User.Sid, nil
+}

client/internal/elevate/trusted_windows_test.go

@@ -0,0 +1,126 @@
+package elevate
+
+import (
+	"os"
+	"path/filepath"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+	"golang.org/x/sys/windows"
+)
+
+// A file the test user created under their own profile, which is what a per-user
+// install looks like. The whole chain up to the volume root is walked, so this is
+// also what says the walk does not refuse an ordinary Windows installation: the
+// root of every volume grants BUILTIN\Users rights that are not ours to worry
+// about.
+func TestCheckOnlyOwnerWritableAcceptsOwnFile(t *testing.T) {
+	err := checkOnlyOwnerWritable(writeExecutable(t))
+	assert.NoError(t, err, "a file the test user owns, under directories only administrators can write")
+}
+
+// Write access held by an account that cannot answer the UAC prompt means that
+// account decides what runs behind it, whoever the ACE names. The trustees that
+// must not have it cannot be listed, so the check names the ones that may.
+func TestCheckOnlyOwnerWritableRejectsUntrustedWriters(t *testing.T) {
+	tests := []struct {
+		name      string
+		wellKnown windows.WELL_KNOWN_SID_TYPE
+	}{
+		{name: "everyone", wellKnown: windows.WinWorldSid},
+		{name: "authenticated users", wellKnown: windows.WinAuthenticatedUserSid},
+		{name: "builtin users", wellKnown: windows.WinBuiltinUsersSid},
+		// A service account, which no denylist of the obvious groups would name
+		// and which cannot elevate any more than Everyone can.
+		{name: "local service", wellKnown: windows.WinLocalServiceSid},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			path := writeExecutable(t)
+			grantWrite(t, path, tt.wellKnown)
+
+			assert.Error(t, checkOnlyOwnerWritable(path),
+				"write access for %s must be refused", tt.name)
+		})
+	}
+}
+
+// The masks are the policy: on a file any write reaches its contents, while on a
+// directory only deleting or taking over an entry reaches something already
+// there. Adding an entry does not, which is why the walk survives a volume root.
+func TestWriteAccessMasks(t *testing.T) {
+	assert.NotZero(t, fileWriteAccess&windows.FILE_WRITE_DATA, "writing a file's data reaches its contents")
+	assert.NotZero(t, fileWriteAccess&windows.FILE_APPEND_DATA, "appending to a file reaches its contents")
+
+	assert.Zero(t, dirWriteAccess&windows.FILE_WRITE_DATA, "adding a file to a directory replaces nothing")
+	assert.Zero(t, dirWriteAccess&windows.FILE_APPEND_DATA, "adding a subdirectory replaces nothing")
+	assert.NotZero(t, dirWriteAccess&fileDeleteChild, "deleting an entry replaces it")
+	assert.NotZero(t, dirWriteAccess&windows.DELETE, "deleting the directory takes its entries with it")
+}
+
+func TestIsAllowACE(t *testing.T) {
+	tests := []struct {
+		name    string
+		aceType uint8
+		want    bool
+	}{
+		{name: "allowed", aceType: windows.ACCESS_ALLOWED_ACE_TYPE, want: true},
+		{name: "allowed callback", aceType: accessAllowedCallbackACEType, want: true},
+		{name: "allowed object", aceType: accessAllowedObjectACEType, want: true},
+		{name: "allowed callback object", aceType: accessAllowedCallbackObjectACEType, want: true},
+		{name: "denied", aceType: windows.ACCESS_DENIED_ACE_TYPE},
+		// SYSTEM_AUDIT_ACE_TYPE, which x/sys does not define: an ACE that records
+		// access rather than granting it.
+		{name: "audit", aceType: 0x2},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			assert.Equal(t, tt.want, isAllowACE(tt.aceType), "ACE type %#x", tt.aceType)
+		})
+	}
+}
+
+// writeExecutable creates a plain file under the test's own directory, the shape
+// trustedSelf checks.
+func writeExecutable(t *testing.T) string {
+	t.Helper()
+	path := filepath.Join(t.TempDir(), "netbird-ui.exe")
+	require.NoError(t, os.WriteFile(path, []byte("MZ"), 0o755), "write the executable")
+	return path
+}
+
+// grantWrite replaces the file's DACL with one that grants a well-known trustee
+// everything, keeping the test user's own access so the file stays deletable.
+func grantWrite(t *testing.T, path string, wellKnown windows.WELL_KNOWN_SID_TYPE) {
+	t.Helper()
+
+	trustee, err := windows.CreateWellKnownSid(wellKnown)
+	require.NoError(t, err, "build the trustee SID")
+	self, err := currentUserSID()
+	require.NoError(t, err, "read the test user's SID")
+
+	acl, err := windows.ACLFromEntries([]windows.EXPLICIT_ACCESS{
+		fullControl(self, windows.TRUSTEE_IS_USER),
+		fullControl(trustee, windows.TRUSTEE_IS_WELL_KNOWN_GROUP),
+	}, nil)
+	require.NoError(t, err, "build the ACL")
+
+	require.NoError(t, windows.SetNamedSecurityInfo(path, windows.SE_FILE_OBJECT,
+		windows.DACL_SECURITY_INFORMATION|windows.PROTECTED_DACL_SECURITY_INFORMATION,
+		nil, nil, acl, nil), "set the DACL")
+}
+
+func fullControl(sid *windows.SID, trusteeType uint32) windows.EXPLICIT_ACCESS {
+	return windows.EXPLICIT_ACCESS{
+		AccessPermissions: windows.GENERIC_ALL,
+		AccessMode:        windows.GRANT_ACCESS,
+		Trustee: windows.TRUSTEE{
+			TrusteeForm:  windows.TRUSTEE_IS_SID,
+			TrusteeType:  windows.TRUSTEE_TYPE(trusteeType),
+			TrusteeValue: windows.TrusteeValueFromSID(sid),
+		},
+	}
+}

client/internal/engine.go

@@ -59,6 +59,7 @@ import (
 	"github.com/netbirdio/netbird/client/internal/syncstore"
 	"github.com/netbirdio/netbird/client/internal/updater"
 	"github.com/netbirdio/netbird/client/jobexec"
+	"github.com/netbirdio/netbird/client/netstate"
 	cProto "github.com/netbirdio/netbird/client/proto"
 	"github.com/netbirdio/netbird/client/system"
 	nbdns "github.com/netbirdio/netbird/dns"
@@ -181,6 +182,9 @@ type EngineServices struct {
 	UpdateManager  *updater.Manager
 	ClientMetrics  *metrics.ClientMetrics
 	MetricsCtx     context.Context
+	// NetState gates the reconnection loops on OS-reported network
+	// availability; nil disables gating.
+	NetState *netstate.State
 }
 
 // Engine is a mechanism responsible for reacting on Signal and Management stream events and managing connections to the remote peers.
@@ -204,6 +208,10 @@ type Engine struct {
 	config    *EngineConfig
 	mobileDep MobileDependency
 
+	// netState gates the peer reconnection guards on OS-reported network
+	// availability; nil disables gating.
+	netState *netstate.State
+
 	// STUNs is a list of STUN servers used by ICE
 	STUNs []*stun.URI
 	// TURNs is a list of STUN servers used by ICE
@@ -337,6 +345,7 @@ func NewEngine(
 		syncMsgMux:         &sync.Mutex{},
 		config:             config,
 		mobileDep:          mobileDep,
+		netState:           services.NetState,
 		STUNs:              []*stun.URI{},
 		TURNs:              []*stun.URI{},
 		networkSerial:      0,
@@ -1893,7 +1902,8 @@ func (e *Engine) createPeerConn(pubKey string, allowedIPs []netip.Prefix, agentV
 			Addr:           e.getRosenpassAddr(),
 			PermissiveMode: e.config.RosenpassPermissive,
 		},
-		ICEConfig: e.createICEConfig(),
+		ICEConfig:    e.createICEConfig(),
+		NetworkState: e.netState,
 	}
 
 	serviceDependencies := peer.ServiceDependencies{
@@ -2562,7 +2572,7 @@ func (e *Engine) SetCapture(pc device.PacketCapture) error {
 	}
 
 	afc := capture.NewAFPacketCapture(intf.Name(), sess)
-	if err := afc.Start(); err != nil {
+	if err := afc.Start(); err != nil { //nolint:staticcheck // always errors on non-Linux builds
 		return fmt.Errorf("start AF_PACKET capture on %s: %w", intf.Name(), err)
 	}
 	e.afpacketCapture = afc

client/internal/engine_privileged_test.go

@@ -12,7 +12,7 @@ import (
 	"testing"
 	"time"
 
-	"github.com/golang/mock/gomock"
+	"go.uber.org/mock/gomock"
 	"github.com/google/uuid"
 	log "github.com/sirupsen/logrus"
 	"github.com/stretchr/testify/assert"

client/internal/getent/cgo_unix.go

@@ -0,0 +1,36 @@
+//go:build cgo && !osusergo && !windows
+
+package getent
+
+import "os/user"
+
+// Built with cgo, os/user resolves through libc (getpwnam_r and friends),
+// which goes through the host's NSS stack natively. Whatever it fails to
+// find, the getent command would not find either, so there is nothing to
+// fall back to.
+
+// LookupUser looks up a user by name.
+func LookupUser(username string) (*user.User, error) {
+	return user.Lookup(username)
+}
+
+// LookupUserID looks up a user by UID.
+func LookupUserID(uid string) (*user.User, error) {
+	return user.LookupId(uid)
+}
+
+// CurrentUser returns the user this process runs as.
+func CurrentUser() (*user.User, error) {
+	return user.Current()
+}
+
+// LookupGroupID looks up a group by GID.
+func LookupGroupID(gid string) (*user.Group, error) {
+	return user.LookupGroupId(gid)
+}
+
+// GroupIDs returns the IDs of the groups the user is a member of; libc's
+// getgrouplist handles NSS groups natively.
+func GroupIDs(u *user.User) ([]string, error) {
+	return u.GroupIds()
+}

client/internal/getent/getent.go

@@ -0,0 +1,6 @@
+// Package getent resolves users and groups through the host's NSS stack.
+// Built without cgo, os/user reads /etc/passwd and /etc/group alone and misses
+// anything LDAP, SSSD or winbind provide; the getent and id commands resolve
+// through NSS whatever the build. The lookups here try the standard library
+// first, which needs no subprocess, and fall back to those commands.
+package getent

client/internal/getent/getent_test.go

@@ -1,4 +1,4 @@
-package server
+package getent
 
 import (
 	"os/user"
@@ -10,38 +10,48 @@ import (
 	"github.com/stretchr/testify/require"
 )
 
-func TestLookupWithGetent_CurrentUser(t *testing.T) {
+func TestLookupUser_CurrentUser(t *testing.T) {
 	// The current user should always be resolvable on any platform
 	current, err := user.Current()
 	require.NoError(t, err)
 
-	u, err := lookupWithGetent(current.Username)
+	u, err := LookupUser(current.Username)
 	require.NoError(t, err)
 	assert.Equal(t, current.Username, u.Username)
 	assert.Equal(t, current.Uid, u.Uid)
 	assert.Equal(t, current.Gid, u.Gid)
 }
 
-func TestLookupWithGetent_NonexistentUser(t *testing.T) {
-	_, err := lookupWithGetent("nonexistent_user_xyzzy_12345")
+func TestLookupUser_NonexistentUser(t *testing.T) {
+	_, err := LookupUser("nonexistent_user_xyzzy_12345")
 	require.Error(t, err, "should fail for nonexistent user")
 }
 
-func TestCurrentUserWithGetent(t *testing.T) {
+func TestLookupUserID_CurrentUser(t *testing.T) {
+	current, err := user.Current()
+	require.NoError(t, err)
+
+	u, err := LookupUserID(current.Uid)
+	require.NoError(t, err)
+	assert.Equal(t, current.Username, u.Username)
+	assert.Equal(t, current.Uid, u.Uid)
+}
+
+func TestCurrentUser(t *testing.T) {
 	stdUser, err := user.Current()
 	require.NoError(t, err)
 
-	u, err := currentUserWithGetent()
+	u, err := CurrentUser()
 	require.NoError(t, err)
 	assert.Equal(t, stdUser.Uid, u.Uid)
 	assert.Equal(t, stdUser.Username, u.Username)
 }
 
-func TestGroupIdsWithFallback_CurrentUser(t *testing.T) {
+func TestGroupIDs_CurrentUser(t *testing.T) {
 	current, err := user.Current()
 	require.NoError(t, err)
 
-	groups, err := groupIdsWithFallback(current)
+	groups, err := GroupIDs(current)
 	require.NoError(t, err)
 	require.NotEmpty(t, groups, "current user should have at least one group")
 
@@ -53,32 +63,30 @@ func TestGroupIdsWithFallback_CurrentUser(t *testing.T) {
 	}
 }
 
-func TestGetShellFromGetent_CurrentUser(t *testing.T) {
-	if runtime.GOOS == "windows" {
-		// Windows stub always returns empty, which is correct
-		shell := getShellFromGetent("1000")
-		assert.Empty(t, shell, "Windows stub should return empty")
-		return
-	}
-
+func TestUserShell_CurrentUser(t *testing.T) {
 	current, err := user.Current()
 	require.NoError(t, err)
 
-	// getent may not be available on all systems (e.g., macOS without Homebrew getent)
-	shell := getShellFromGetent(current.Uid)
+	// getent may not be available on all systems (e.g., macOS without
+	// Homebrew getent), and Windows has no login shells at all.
+	shell, err := UserShell(current.Uid)
+	if err != nil {
+		t.Logf("UserShell failed, getent may not be available: %v", err)
+		return
+	}
 	if shell == "" {
-		t.Log("getShellFromGetent returned empty, getent may not be available")
+		t.Log("UserShell returned empty, the user has no shell set")
 		return
 	}
 	assert.True(t, shell[0] == '/', "shell should be an absolute path, got %q", shell)
 }
 
-func TestLookupWithGetent_RootUser(t *testing.T) {
+func TestLookupUser_RootUser(t *testing.T) {
 	if runtime.GOOS == "windows" {
 		t.Skip("no root user on Windows")
 	}
 
-	u, err := lookupWithGetent("root")
+	u, err := LookupUser("root")
 	if err != nil {
 		t.Skip("root user not available on this system")
 	}
@@ -86,25 +94,25 @@ func TestLookupWithGetent_RootUser(t *testing.T) {
 }
 
 // TestIntegration_FullLookupChain exercises the complete user lookup chain
-// against the real system, testing that all wrappers (lookupWithGetent,
-// currentUserWithGetent, groupIdsWithFallback, getShellFromGetent) produce
-// consistent and correct results when composed together.
+// against the real system, testing that all wrappers (LookupUser,
+// CurrentUser, GroupIDs, UserShell) produce consistent and correct results
+// when composed together.
 func TestIntegration_FullLookupChain(t *testing.T) {
-	// Step 1: currentUserWithGetent must resolve the running user.
-	current, err := currentUserWithGetent()
-	require.NoError(t, err, "currentUserWithGetent must resolve the running user")
+	// Step 1: CurrentUser must resolve the running user.
+	current, err := CurrentUser()
+	require.NoError(t, err, "CurrentUser must resolve the running user")
 	require.NotEmpty(t, current.Uid)
 	require.NotEmpty(t, current.Username)
 
-	// Step 2: lookupWithGetent by the same username must return matching identity.
-	byName, err := lookupWithGetent(current.Username)
+	// Step 2: LookupUser by the same username must return matching identity.
+	byName, err := LookupUser(current.Username)
 	require.NoError(t, err)
 	assert.Equal(t, current.Uid, byName.Uid, "lookup by name should return same UID")
 	assert.Equal(t, current.Gid, byName.Gid, "lookup by name should return same GID")
 	assert.Equal(t, current.HomeDir, byName.HomeDir, "lookup by name should return same home")
 
-	// Step 3: groupIdsWithFallback must return at least the primary GID.
-	groups, err := groupIdsWithFallback(current)
+	// Step 3: GroupIDs must return at least the primary GID.
+	groups, err := GroupIDs(current)
 	require.NoError(t, err)
 	require.NotEmpty(t, groups, "user must have at least one group")
 
@@ -119,29 +127,20 @@ func TestIntegration_FullLookupChain(t *testing.T) {
 		}
 	}
 	assert.True(t, foundPrimary, "primary GID %s should appear in supplementary groups", current.Gid)
-
-	// Step 4: getShellFromGetent should either return a valid shell path or empty
-	// (empty is OK when getent is not available, e.g. macOS without Homebrew getent).
-	if runtime.GOOS != "windows" {
-		shell := getShellFromGetent(current.Uid)
-		if shell != "" {
-			assert.True(t, shell[0] == '/', "shell should be an absolute path, got %q", shell)
-		}
-	}
 }
 
 // TestIntegration_LookupAndGroupsConsistency verifies that a user resolved via
-// lookupWithGetent can have their groups resolved via groupIdsWithFallback,
-// testing the handoff between the two functions as used by the SSH server.
+// LookupUser can have their groups resolved via GroupIDs, testing the handoff
+// between the two functions as used by the SSH server.
 func TestIntegration_LookupAndGroupsConsistency(t *testing.T) {
 	current, err := user.Current()
 	require.NoError(t, err)
 
 	// Simulate the SSH server flow: lookup user, then get their groups.
-	resolved, err := lookupWithGetent(current.Username)
+	resolved, err := LookupUser(current.Username)
 	require.NoError(t, err)
 
-	groups, err := groupIdsWithFallback(resolved)
+	groups, err := GroupIDs(resolved)
 	require.NoError(t, err)
 	require.NotEmpty(t, groups, "resolved user must have groups")
 
@@ -154,19 +153,3 @@ func TestIntegration_LookupAndGroupsConsistency(t *testing.T) {
 		}
 	}
 }
-
-// TestIntegration_ShellLookupChain tests the full shell resolution chain
-// (getShellFromPasswd -> getShellFromGetent -> $SHELL -> default) on Unix.
-func TestIntegration_ShellLookupChain(t *testing.T) {
-	if runtime.GOOS == "windows" {
-		t.Skip("Unix shell lookup not applicable on Windows")
-	}
-
-	current, err := user.Current()
-	require.NoError(t, err)
-
-	// getUserShell is the top-level function used by the SSH server.
-	shell := getUserShell(current.Uid)
-	require.NotEmpty(t, shell, "getUserShell must always return a shell")
-	assert.True(t, shell[0] == '/', "shell should be an absolute path, got %q", shell)
-}

client/internal/getent/nocgo_unix.go

@@ -0,0 +1,110 @@
+//go:build (!cgo || osusergo) && !windows
+
+package getent
+
+import (
+	"os"
+	"os/user"
+	"strconv"
+
+	log "github.com/sirupsen/logrus"
+)
+
+// Without cgo, os/user only reads /etc/passwd and /etc/group and misses
+// NSS-provided users and groups; the getent and id commands go through the
+// host's NSS stack.
+
+// LookupUser looks up a user by name, falling back to getent if os/user fails.
+func LookupUser(username string) (*user.User, error) {
+	u, err := user.Lookup(username)
+	if err == nil {
+		return u, nil
+	}
+
+	stdErr := err
+	log.Debugf("os/user.Lookup(%q) failed, trying getent: %v", username, err)
+
+	u, _, getentErr := passwdLookup(username)
+	if getentErr != nil {
+		log.Debugf("getent fallback for %q also failed: %v", username, getentErr)
+		return nil, stdErr
+	}
+	return u, nil
+}
+
+// LookupUserID looks up a user by UID, falling back to getent if os/user fails.
+func LookupUserID(uid string) (*user.User, error) {
+	u, err := user.LookupId(uid)
+	if err == nil {
+		return u, nil
+	}
+
+	stdErr := err
+	log.Debugf("os/user.LookupId(%q) failed, trying getent: %v", uid, err)
+
+	u, _, getentErr := passwdLookup(uid)
+	if getentErr != nil {
+		log.Debugf("getent fallback for uid %s also failed: %v", uid, getentErr)
+		return nil, stdErr
+	}
+	return u, nil
+}
+
+// CurrentUser returns the user this process runs as, falling back to getent
+// if os/user fails.
+func CurrentUser() (*user.User, error) {
+	u, err := user.Current()
+	if err == nil {
+		return u, nil
+	}
+
+	stdErr := err
+	uid := strconv.Itoa(os.Getuid())
+	log.Debugf("os/user.Current() failed, trying getent with UID %s: %v", uid, err)
+
+	u, _, getentErr := passwdLookup(uid)
+	if getentErr != nil {
+		return nil, stdErr
+	}
+	return u, nil
+}
+
+// LookupGroupID looks up a group by GID, falling back to getent if os/user
+// fails.
+func LookupGroupID(gid string) (*user.Group, error) {
+	g, err := user.LookupGroupId(gid)
+	if err == nil {
+		return g, nil
+	}
+
+	stdErr := err
+	log.Debugf("os/user.LookupGroupId(%q) failed, trying getent: %v", gid, err)
+
+	g, _, getentErr := groupLookup(gid)
+	if getentErr != nil {
+		log.Debugf("getent fallback for gid %s also failed: %v", gid, getentErr)
+		return nil, stdErr
+	}
+	return g, nil
+}
+
+// GroupIDs returns the IDs of the groups the user is a member of.
+// NOTE: unlike the lookups above, which try the standard library first, this
+// intentionally tries `id -G` first because without cgo, user.GroupIds only
+// reads /etc/group and silently returns incomplete results for NSS users
+// (no error, just missing groups). The id command goes through NSS and
+// returns the full set.
+func GroupIDs(u *user.User) ([]string, error) {
+	ids, err := idGroups(u.Username)
+	if err == nil {
+		return ids, nil
+	}
+
+	log.Debugf("id -G %q failed, falling back to user.GroupIds(): %v", u.Username, err)
+
+	ids, stdErr := u.GroupIds()
+	if stdErr != nil {
+		return nil, stdErr
+	}
+	return ids, nil
+}

client/internal/getent/unix.go

@@ -0,0 +1,224 @@
+//go:build !windows
+
+package getent
+
+import (
+	"bufio"
+	"context"
+	"fmt"
+	"os"
+	"os/exec"
+	"os/user"
+	"runtime"
+	"strings"
+	"time"
+
+	log "github.com/sirupsen/logrus"
+)
+
+const commandTimeout = 5 * time.Second
+
+// groupFile lists which accounts are in which group, for hosts where the
+// getent command is not available (macOS ships without it).
+const groupFile = "/etc/group"
+
+// UserShell returns the login shell getent reports for the user with this UID.
+// It reaches shells that /etc/passwd does not list, because getent resolves
+// through the host's NSS stack.
+func UserShell(uid string) (string, error) {
+	_, shell, err := passwdLookup(uid)
+	if err != nil {
+		return "", err
+	}
+	return shell, nil
+}
+
+// GroupMembers returns the names of the group's members: from getent, which
+// resolves through NSS, or from /etc/group where getent is not available. A
+// group neither source describes is an error; an empty member list is not,
+// since accounts with the group as their primary one are not listed in it.
+func GroupMembers(name string) ([]string, error) {
+	_, members, err := groupLookup(name)
+	if err == nil {
+		return members, nil
+	}
+	log.Debugf("getent cannot list group %q, reading %s: %v", name, groupFile, err)
+	return groupMembersFromFile(groupFile, name)
+}
+
+// passwdLookup executes `getent passwd <query>`, where query is a username or
+// UID, and returns the user and login shell.
+func passwdLookup(query string) (*user.User, string, error) {
+	out, err := run("passwd", query)
+	if err != nil {
+		return nil, "", err
+	}
+	return parsePasswd(string(out))
+}
+
+// groupLookup executes `getent group <query>`, where query is a group name or
+// GID, and returns the group and its member names.
+func groupLookup(query string) (*user.Group, []string, error) {
+	out, err := run("group", query)
+	if err != nil {
+		return nil, nil, err
+	}
+	return parseGroup(string(out))
+}
+
+// run executes `getent <database> <key>` with a timeout.
+func run(database, key string) ([]byte, error) {
+	if !validateInput(key) {
+		return nil, fmt.Errorf("invalid getent input: %q", key)
+	}
+
+	ctx, cancel := context.WithTimeout(context.Background(), commandTimeout)
+	defer cancel()
+
+	out, err := exec.CommandContext(ctx, "getent", database, key).Output()
+	if err != nil {
+		return nil, fmt.Errorf("getent %s %s: %w", database, key, err)
+	}
+	return out, nil
+}
+
+// parsePasswd parses getent passwd output: "name:x:uid:gid:gecos:home:shell"
+func parsePasswd(output string) (*user.User, string, error) {
+	fields := strings.SplitN(strings.TrimSpace(output), ":", 8)
+	if len(fields) < 6 {
+		return nil, "", fmt.Errorf("unexpected getent output (need 6+ fields): %q", output)
+	}
+
+	if fields[0] == "" || fields[2] == "" || fields[3] == "" {
+		return nil, "", fmt.Errorf("missing required fields in getent output: %q", output)
+	}
+
+	var shell string
+	if len(fields) >= 7 {
+		shell = fields[6]
+	}
+
+	return &user.User{
+		Username: fields[0],
+		Uid:      fields[2],
+		Gid:      fields[3],
+		Name:     fields[4],
+		HomeDir:  fields[5],
+	}, shell, nil
+}
+
+// parseGroup parses getent group output: "name:x:gid:member,member"
+func parseGroup(output string) (*user.Group, []string, error) {
+	fields := strings.SplitN(strings.TrimSpace(output), ":", 4)
+	if len(fields) < 3 {
+		return nil, nil, fmt.Errorf("unexpected getent output (need 3+ fields): %q", output)
+	}
+
+	if fields[0] == "" || fields[2] == "" {
+		return nil, nil, fmt.Errorf("missing required fields in getent output: %q", output)
+	}
+
+	var members []string
+	if len(fields) >= 4 {
+		members = splitMembers(fields[3])
+	}
+	return &user.Group{Name: fields[0], Gid: fields[2]}, members, nil
+}
+
+func splitMembers(list string) []string {
+	var members []string
+	for member := range strings.SplitSeq(list, ",") {
+		if member != "" {
+			members = append(members, member)
+		}
+	}
+	return members
+}
+
+// groupMembersFromFile finds the group's member list in a file of /etc/group's
+// format. A group the file does not describe, because it comes from LDAP or
+// another NSS source, is an error rather than an empty list.
+func groupMembersFromFile(path, name string) ([]string, error) {
+	file, err := os.Open(path)
+	if err != nil {
+		return nil, fmt.Errorf("open %s: %w", path, err)
+	}
+	defer func() {
+		if err := file.Close(); err != nil {
+			log.Debugf("close %s: %v", path, err)
+		}
+	}()
+
+	scanner := bufio.NewScanner(file)
+	for scanner.Scan() {
+		// name:password:gid:member,member
+		fields := strings.Split(scanner.Text(), ":")
+		if len(fields) < 4 || fields[0] != name {
+			continue
+		}
+		return splitMembers(fields[3]), nil
+	}
+	if err := scanner.Err(); err != nil {
+		return nil, fmt.Errorf("read %s: %w", path, err)
+	}
+	return nil, fmt.Errorf("%s does not describe group %q", path, name)
+}
+
+// validateInput checks that the input is safe to pass to getent or id.
+// Allows POSIX usernames, numeric IDs, and common NSS extensions
+// (@ for Kerberos, $ for Samba, + for NIS compat). A leading hyphen is
+// rejected so the input can never be parsed as a command-line flag.
+func validateInput(input string) bool {
+	maxLen := 32
+	if runtime.GOOS == "linux" {
+		maxLen = 256
+	}
+
+	if len(input) == 0 || len(input) > maxLen {
+		return false
+	}
+
+	if input[0] == '-' {
+		return false
+	}
+
+	for _, r := range input {
+		if isAllowedChar(r) {
+			continue
+		}
+		return false
+	}
+	return true
+}
+
+func isAllowedChar(r rune) bool {
+	if r >= 'a' && r <= 'z' || r >= 'A' && r <= 'Z' || r >= '0' && r <= '9' {
+		return true
+	}
+	switch r {
+	case '.', '_', '-', '@', '+', '$':
+		return true
+	}
+	return false
+}
+
+// idGroups runs `id -G <username>` and returns the space-separated group IDs.
+func idGroups(username string) ([]string, error) {
+	if !validateInput(username) {
+		return nil, fmt.Errorf("invalid username for id command: %q", username)
+	}
+
+	ctx, cancel := context.WithTimeout(context.Background(), commandTimeout)
+	defer cancel()
+
+	out, err := exec.CommandContext(ctx, "id", "-G", username).Output()
+	if err != nil {
+		return nil, fmt.Errorf("id -G %s: %w", username, err)
+	}
+
+	trimmed := strings.TrimSpace(string(out))
+	if trimmed == "" {
+		return nil, fmt.Errorf("id -G %s: empty output", username)
+	}
+	return strings.Fields(trimmed), nil
+}

client/internal/getent/unix_test.go

@@ -1,10 +1,12 @@
 //go:build !windows
 
-package server
+package getent
 
 import (
+	"os"
 	"os/exec"
 	"os/user"
+	"path/filepath"
 	"runtime"
 	"strconv"
 	"testing"
@@ -13,7 +15,7 @@ import (
 	"github.com/stretchr/testify/require"
 )
 
-func TestParseGetentPasswd(t *testing.T) {
+func TestParsePasswd(t *testing.T) {
 	tests := []struct {
 		name        string
 		input       string
@@ -128,7 +130,7 @@ func TestParseGetentPasswd(t *testing.T) {
 
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
-			u, shell, err := parseGetentPasswd(tt.input)
+			u, shell, err := parsePasswd(tt.input)
 			if tt.wantErr {
 				require.Error(t, err)
 				if tt.errContains != "" {
@@ -147,7 +149,120 @@ func TestParseGetentPasswd(t *testing.T) {
 	}
 }
 
-func TestValidateGetentInput(t *testing.T) {
+func TestParseGroup(t *testing.T) {
+	tests := []struct {
+		name        string
+		input       string
+		wantGroup   *user.Group
+		wantMembers []string
+		wantErr     bool
+	}{
+		{
+			name:      "no members",
+			input:     "vma:x:1000:\n",
+			wantGroup: &user.Group{Name: "vma", Gid: "1000"},
+		},
+		{
+			name:        "one member",
+			input:       "sudo:x:27:alice",
+			wantGroup:   &user.Group{Name: "sudo", Gid: "27"},
+			wantMembers: []string{"alice"},
+		},
+		{
+			name:        "several members",
+			input:       "docker:x:998:alice,bob\n",
+			wantGroup:   &user.Group{Name: "docker", Gid: "998"},
+			wantMembers: []string{"alice", "bob"},
+		},
+		{
+			name:    "too few fields",
+			input:   "bad:x",
+			wantErr: true,
+		},
+		{
+			name:    "empty group name",
+			input:   ":x:1000:alice",
+			wantErr: true,
+		},
+		{
+			name:    "empty GID",
+			input:   "vma:x::alice",
+			wantErr: true,
+		},
+		{
+			name:    "empty input",
+			input:   "",
+			wantErr: true,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			g, members, err := parseGroup(tt.input)
+			if tt.wantErr {
+				require.Error(t, err)
+				return
+			}
+			require.NoError(t, err)
+			assert.Equal(t, tt.wantGroup.Name, g.Name, "group name")
+			assert.Equal(t, tt.wantGroup.Gid, g.Gid, "GID")
+			assert.Equal(t, tt.wantMembers, members, "members")
+		})
+	}
+}
+
+func TestGroupMembersFromFile(t *testing.T) {
+	tests := []struct {
+		name  string
+		entry string
+		want  []string
+	}{
+		{name: "no members", entry: "vma:x:1000:"},
+		{name: "only the owner", entry: "vma:x:1000:vma", want: []string{"vma"}},
+		{name: "two members", entry: "vma:x:1000:vma,bob", want: []string{"vma", "bob"}},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			path := filepath.Join(t.TempDir(), "group")
+			body := "root:x:0:\n" + tt.entry + "\nsudo:x:27:vma\n"
+			require.NoError(t, os.WriteFile(path, []byte(body), 0o644), "write the group file")
+
+			members, err := groupMembersFromFile(path, "vma")
+			require.NoError(t, err, "entry %q", tt.entry)
+			assert.Equal(t, tt.want, members, "entry %q", tt.entry)
+		})
+	}
+}
+
+// A group the file does not describe, because it comes from LDAP or another
+// NSS source, is an error rather than an empty member list: the caller must
+// be able to tell "no members" from "no answer".
+func TestGroupMembersFromFileUnknownGroup(t *testing.T) {
+	path := filepath.Join(t.TempDir(), "group")
+	require.NoError(t, os.WriteFile(path, []byte("root:x:0:\n"), 0o644), "write the group file")
+
+	_, err := groupMembersFromFile(path, "vma")
+	assert.Error(t, err, "a group the file does not describe")
+
+	_, err = groupMembersFromFile(filepath.Join(t.TempDir(), "absent"), "vma")
+	assert.Error(t, err, "no group file at all")
+}
+
+// GroupMembers on the root group, which every Unix has, whichever source
+// answers for it.
+func TestGroupMembers_RootGroup(t *testing.T) {
+	rootGroup := "root"
+	switch runtime.GOOS {
+	case "darwin", "dragonfly", "freebsd", "netbsd", "openbsd":
+		rootGroup = "wheel"
+	}
+
+	_, err := GroupMembers(rootGroup)
+	assert.NoError(t, err, "the %s group must be describable", rootGroup)
+}
+
+func TestValidateInput(t *testing.T) {
 	tests := []struct {
 		name  string
 		input string
@@ -180,7 +295,7 @@ func TestValidateGetentInput(t *testing.T) {
 
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
-			assert.Equal(t, tt.want, validateGetentInput(tt.input))
+			assert.Equal(t, tt.want, validateInput(tt.input))
 		})
 	}
 }
@@ -193,12 +308,12 @@ func makeLongString(n int) string {
 	return string(b)
 }
 
-func TestRunGetent_RootUser(t *testing.T) {
+func TestPasswdLookup_RootUser(t *testing.T) {
 	if _, err := exec.LookPath("getent"); err != nil {
 		t.Skip("getent not available on this system")
 	}
 
-	u, shell, err := runGetent("root")
+	u, shell, err := passwdLookup("root")
 	require.NoError(t, err)
 	assert.Equal(t, "root", u.Username)
 	assert.Equal(t, "0", u.Uid)
@@ -206,44 +321,55 @@ func TestRunGetent_RootUser(t *testing.T) {
 	assert.NotEmpty(t, shell, "root should have a shell")
 }
 
-func TestRunGetent_ByUID(t *testing.T) {
+func TestPasswdLookup_ByUID(t *testing.T) {
 	if _, err := exec.LookPath("getent"); err != nil {
 		t.Skip("getent not available on this system")
 	}
 
-	u, _, err := runGetent("0")
+	u, _, err := passwdLookup("0")
 	require.NoError(t, err)
 	assert.Equal(t, "root", u.Username)
 	assert.Equal(t, "0", u.Uid)
 }
 
-func TestRunGetent_NonexistentUser(t *testing.T) {
+func TestPasswdLookup_NonexistentUser(t *testing.T) {
 	if _, err := exec.LookPath("getent"); err != nil {
 		t.Skip("getent not available on this system")
 	}
 
-	_, _, err := runGetent("nonexistent_user_xyzzy_12345")
+	_, _, err := passwdLookup("nonexistent_user_xyzzy_12345")
 	assert.Error(t, err)
 }
 
-func TestRunGetent_InvalidInput(t *testing.T) {
-	_, _, err := runGetent("")
+func TestPasswdLookup_InvalidInput(t *testing.T) {
+	_, _, err := passwdLookup("")
 	assert.Error(t, err)
 
-	_, _, err = runGetent("user\x00name")
+	_, _, err = passwdLookup("user\x00name")
 	assert.Error(t, err)
 }
 
-func TestRunGetent_NotAvailable(t *testing.T) {
+func TestPasswdLookup_NotAvailable(t *testing.T) {
 	if _, err := exec.LookPath("getent"); err == nil {
 		t.Skip("getent is available, can't test missing case")
 	}
 
-	_, _, err := runGetent("root")
+	_, _, err := passwdLookup("root")
 	assert.Error(t, err, "should fail when getent is not installed")
 }
 
-func TestRunIdGroups_CurrentUser(t *testing.T) {
+func TestGroupLookup_RootGroup(t *testing.T) {
+	if _, err := exec.LookPath("getent"); err != nil {
+		t.Skip("getent not available on this system")
+	}
+
+	g, _, err := groupLookup("0")
+	require.NoError(t, err)
+	assert.Equal(t, "0", g.Gid, "GID 0 resolves to the root group")
+	assert.NotEmpty(t, g.Name, "the root group has a name")
+}
+
+func TestIdGroups_CurrentUser(t *testing.T) {
 	if _, err := exec.LookPath("id"); err != nil {
 		t.Skip("id not available on this system")
 	}
@@ -251,7 +377,7 @@ func TestRunIdGroups_CurrentUser(t *testing.T) {
 	current, err := user.Current()
 	require.NoError(t, err)
 
-	groups, err := runIdGroups(current.Username)
+	groups, err := idGroups(current.Username)
 	require.NoError(t, err)
 	require.NotEmpty(t, groups, "current user should have at least one group")
 
@@ -261,20 +387,20 @@ func TestRunIdGroups_CurrentUser(t *testing.T) {
 	}
 }
 
-func TestRunIdGroups_NonexistentUser(t *testing.T) {
+func TestIdGroups_NonexistentUser(t *testing.T) {
 	if _, err := exec.LookPath("id"); err != nil {
 		t.Skip("id not available on this system")
 	}
 
-	_, err := runIdGroups("nonexistent_user_xyzzy_12345")
+	_, err := idGroups("nonexistent_user_xyzzy_12345")
 	assert.Error(t, err)
 }
 
-func TestRunIdGroups_InvalidInput(t *testing.T) {
-	_, err := runIdGroups("")
+func TestIdGroups_InvalidInput(t *testing.T) {
+	_, err := idGroups("")
 	assert.Error(t, err)
 
-	_, err = runIdGroups("user\x00name")
+	_, err = idGroups("user\x00name")
 	assert.Error(t, err)
 }
 
@@ -286,7 +412,7 @@ func TestGetentResultsMatchStdlib(t *testing.T) {
 	current, err := user.Current()
 	require.NoError(t, err)
 
-	getentUser, _, err := runGetent(current.Username)
+	getentUser, _, err := passwdLookup(current.Username)
 	require.NoError(t, err)
 
 	assert.Equal(t, current.Username, getentUser.Username, "username should match")
@@ -303,7 +429,7 @@ func TestGetentResultsMatchStdlib_ByUID(t *testing.T) {
 	current, err := user.Current()
 	require.NoError(t, err)
 
-	getentUser, _, err := runGetent(current.Uid)
+	getentUser, _, err := passwdLookup(current.Uid)
 	require.NoError(t, err)
 
 	assert.Equal(t, current.Username, getentUser.Username, "username should match when looked up by UID")
@@ -323,12 +449,12 @@ func TestIdGroupsMatchStdlib(t *testing.T) {
 		t.Skip("os/user.GroupIds() not working, likely CGO_ENABLED=0")
 	}
 
-	idGroups, err := runIdGroups(current.Username)
+	idGroupIDs, err := idGroups(current.Username)
 	require.NoError(t, err)
 
 	// Deduplicate both lists: id -G can return duplicates (e.g., root in Docker)
 	// and ElementsMatch treats duplicates as distinct.
-	assert.ElementsMatch(t, uniqueStrings(stdGroups), uniqueStrings(idGroups), "id -G should return same groups as os/user")
+	assert.ElementsMatch(t, uniqueStrings(stdGroups), uniqueStrings(idGroupIDs), "id -G should return same groups as os/user")
 }
 
 func uniqueStrings(ss []string) []string {
@@ -343,71 +469,3 @@ func uniqueStrings(ss []string) []string {
 	}
 	return out
 }
-
-// TestGetShellFromPasswd_CurrentUser verifies that getShellFromPasswd correctly
-// reads the current user's shell from /etc/passwd by comparing it against what
-// getent reports (which goes through NSS).
-func TestGetShellFromPasswd_CurrentUser(t *testing.T) {
-	current, err := user.Current()
-	require.NoError(t, err)
-
-	shell := getShellFromPasswd(current.Uid)
-	if shell == "" {
-		t.Skip("current user not found in /etc/passwd (may be an NSS-only user)")
-	}
-
-	assert.True(t, shell[0] == '/', "shell should be an absolute path, got %q", shell)
-
-	if _, err := exec.LookPath("getent"); err == nil {
-		_, getentShell, getentErr := runGetent(current.Uid)
-		if getentErr == nil && getentShell != "" {
-			assert.Equal(t, getentShell, shell, "shell from /etc/passwd should match getent")
-		}
-	}
-}
-
-// TestGetShellFromPasswd_RootUser verifies that getShellFromPasswd can read
-// root's shell from /etc/passwd. Root is guaranteed to be in /etc/passwd on
-// any standard Unix system.
-func TestGetShellFromPasswd_RootUser(t *testing.T) {
-	shell := getShellFromPasswd("0")
-	require.NotEmpty(t, shell, "root (UID 0) must be in /etc/passwd")
-	assert.True(t, shell[0] == '/', "root shell should be an absolute path, got %q", shell)
-}
-
-// TestGetShellFromPasswd_NonexistentUID verifies that getShellFromPasswd
-// returns empty for a UID that doesn't exist in /etc/passwd.
-func TestGetShellFromPasswd_NonexistentUID(t *testing.T) {
-	shell := getShellFromPasswd("4294967294")
-	assert.Empty(t, shell, "nonexistent UID should return empty shell")
-}
-
-// TestGetShellFromPasswd_MatchesGetentForKnownUsers reads /etc/passwd directly
-// and cross-validates every entry against getent to ensure parseGetentPasswd
-// and getShellFromPasswd agree on shell values.
-func TestGetShellFromPasswd_MatchesGetentForKnownUsers(t *testing.T) {
-	if _, err := exec.LookPath("getent"); err != nil {
-		t.Skip("getent not available")
-	}
-
-	// Pick a few well-known system UIDs that are virtually always in /etc/passwd.
-	uids := []string{"0"} // root
-
-	current, err := user.Current()
-	require.NoError(t, err)
-	uids = append(uids, current.Uid)
-
-	for _, uid := range uids {
-		passwdShell := getShellFromPasswd(uid)
-		if passwdShell == "" {
-			continue
-		}
-
-		_, getentShell, err := runGetent(uid)
-		if err != nil {
-			continue
-		}
-
-		assert.Equal(t, getentShell, passwdShell, "shell mismatch for UID %s", uid)
-	}
-}

client/internal/getent/windows.go

@@ -0,0 +1,36 @@
+//go:build windows
+
+package getent
+
+import (
+	"errors"
+	"os/user"
+)
+
+// Windows does not use NSS or getent; os/user resolves accounts there
+// without cgo, so everything delegates to it.
+
+// LookupUser looks up a user by name.
+func LookupUser(username string) (*user.User, error) {
+	return user.Lookup(username)
+}
+
+// LookupUserID looks up a user by UID.
+func LookupUserID(uid string) (*user.User, error) {
+	return user.LookupId(uid)
+}
+
+// CurrentUser returns the user this process runs as.
+func CurrentUser() (*user.User, error) {
+	return user.Current()
+}
+
+// GroupIDs returns the IDs of the groups the user is a member of.
+func GroupIDs(u *user.User) ([]string, error) {
+	return u.GroupIds()
+}
+
+// UserShell is unanswerable on Windows, which has no login-shell database.
+func UserShell(string) (string, error) {
+	return "", errors.ErrUnsupported
+}

client/internal/ipcauth/privileged.go

@@ -91,6 +91,12 @@ func SelfDelegatesTo() (Identity, bool) {
 	return selfIdentity, true
 }
 
+// The values PrivilegedActorKey returns.
+const (
+	ActorKeyAdministrator = "administrator"
+	ActorKeyRoot          = "root"
+)
+
 // PrivilegedActor names the principal a privileged operation requires, for use
 // in messages shown to the user.
 func PrivilegedActor() string {
@@ -100,6 +106,16 @@ func PrivilegedActor() string {
 	return "root"
 }
 
+// PrivilegedActorKey identifies that principal without wording it, for a client
+// that writes its own message in the user's language. The words PrivilegedActor
+// returns are English, and a translated sentence cannot borrow them.
+func PrivilegedActorKey() string {
+	if runtime.GOOS == "windows" {
+		return ActorKeyAdministrator
+	}
+	return ActorKeyRoot
+}
+
 // ElevatedCommand renders a command so that running it grants the privileges the
 // operation needs. Windows has no in-line equivalent of sudo, so the command is
 // returned unchanged and the user is expected to run it from an elevated

client/internal/peer/conn.go

@@ -26,6 +26,7 @@ import (
 	"github.com/netbirdio/netbird/client/internal/portforward"
 	"github.com/netbirdio/netbird/client/internal/rosenpass"
 	"github.com/netbirdio/netbird/client/internal/stdnet"
+	"github.com/netbirdio/netbird/client/netstate"
 	"github.com/netbirdio/netbird/route"
 	relayClient "github.com/netbirdio/netbird/shared/relay/client"
 )
@@ -93,6 +94,10 @@ type ConnConfig struct {
 
 	// ICEConfig ICE protocol configuration
 	ICEConfig icemaker.Config
+
+	// NetworkState gates the reconnection guard on OS-reported network
+	// availability; nil disables gating.
+	NetworkState *netstate.State
 }
 
 type Conn struct {
@@ -254,7 +259,7 @@ func (conn *Conn) open(engineCtx context.Context, firstPacket []byte) error {
 		conn.handshaker.AddICEListener(conn.workerICE.OnNewOffer)
 	}
 
-	conn.guard = guard.NewGuard(conn.Log, conn.isConnectedOnAllWay, conn.config.Timeout, conn.srWatcher)
+	conn.guard = guard.NewGuard(conn.Log, conn.isConnectedOnAllWay, conn.config.Timeout, conn.srWatcher, conn.config.NetworkState)
 
 	conn.wg.Add(1)
 	go func() {
@@ -440,7 +445,7 @@ func (conn *Conn) onICEConnectionIsReady(priority conntype.ConnPriority, iceConn
 		conn.dumpState.NewLocalProxy()
 		wgProxy, err = conn.newProxy(iceConnInfo.RemoteConn)
 		if err != nil {
-			conn.Log.Errorf("failed to add turn net.Conn to local proxy: %v", err)
+			conn.Log.Errorf("failed to add relayed net.Conn to local proxy: %v", err)
 			return
 		}
 		ep = wgProxy.EndpointAddr()
@@ -878,9 +883,8 @@ func (conn *Conn) newProxy(remoteConn net.Conn) (wgproxy.Proxy, error) {
 	}
 
 	wgProxy := conn.config.WgConfig.WgInterface.GetProxy()
-	if err := wgProxy.AddTurnConn(conn.ctx, udpAddr, remoteConn); err != nil {
-		conn.Log.Errorf("failed to add turn net.Conn to local proxy: %v", err)
-		return nil, err
+	if err := wgProxy.AddRelayedConn(conn.ctx, udpAddr, remoteConn); err != nil {
+		return nil, fmt.Errorf("add relayed conn to proxy: %w", err)
 	}
 	return wgProxy, nil
 }

client/internal/peer/guard/guard.go

@@ -6,6 +6,8 @@ import (
 
 	"github.com/cenkalti/backoff/v4"
 	log "github.com/sirupsen/logrus"
+
+	"github.com/netbirdio/netbird/client/netstate"
 )
 
 // ConnStatus represents the connection state as seen by the guard.
@@ -31,20 +33,26 @@ type connStatusFunc func() ConnStatus
 // - Relayed connection disconnected
 // - ICE candidate changes
 type Guard struct {
-	log                     *log.Entry
-	isConnectedOnAllWay     connStatusFunc
-	timeout                 time.Duration
-	srWatcher               *SRWatcher
+	log                 *log.Entry
+	isConnectedOnAllWay connStatusFunc
+	timeout             time.Duration
+	srWatcher           *SRWatcher
+	// netState gates reconnect attempts on OS-reported network availability;
+	// nil disables gating.
+	netState                *netstate.State
 	relayedConnDisconnected chan struct{}
 	iCEConnDisconnected     chan struct{}
 }
 
-func NewGuard(log *log.Entry, isConnectedFn connStatusFunc, timeout time.Duration, srWatcher *SRWatcher) *Guard {
+// NewGuard creates a reconnection guard for a peer connection. A nil netState
+// disables network availability gating.
+func NewGuard(log *log.Entry, isConnectedFn connStatusFunc, timeout time.Duration, srWatcher *SRWatcher, netState *netstate.State) *Guard {
 	return &Guard{
 		log:                     log,
 		isConnectedOnAllWay:     isConnectedFn,
 		timeout:                 timeout,
 		srWatcher:               srWatcher,
+		netState:                netState,
 		relayedConnDisconnected: make(chan struct{}, 1),
 		iCEConnDisconnected:     make(chan struct{}, 1),
 	}
@@ -96,9 +104,16 @@ func (g *Guard) reconnectLoopWithRetry(ctx context.Context, callback func()) {
 	iceState := &iceRetryState{log: g.log}
 	defer iceState.reset()
 
+	netChanged := g.netState.Changed()
+
 	for {
 		select {
 		case <-tickerChannel:
+			// skip attempts while the OS reports no usable network; the
+			// netChanged case below resumes the loop once it returns
+			if !g.netState.IsOnline() {
+				continue
+			}
 			switch g.isConnectedOnAllWay() {
 			case ConnStatusConnected:
 				// all good, nothing to do
@@ -135,6 +150,23 @@ func (g *Guard) reconnectLoopWithRetry(ctx context.Context, callback func()) {
 			tickerChannel = ticker.C
 			iceState.reset()
 
+		case <-netChanged:
+			// Re-arm for the next transition before acting on this one.
+			netChanged = g.netState.Changed()
+			if !g.netState.IsOnline() {
+				continue
+			}
+			// Ticks skipped while offline drove the backoff towards its
+			// maximum without ever attempting, and left the ICE budget
+			// frozen — possibly in hourly mode. Recover on our own so the
+			// peer does not depend on a signal or relay event that never
+			// comes when both stayed up across the outage.
+			g.log.Debugf("network is back, reset reconnection ticker")
+			ticker.Stop()
+			ticker = g.newReconnectTicker(ctx)
+			tickerChannel = ticker.C
+			iceState.reset()
+
 		case <-ctx.Done():
 			g.log.Debugf("context is done, stop reconnect loop")
 			return

client/internal/peer/guard/guard_leak_test.go

@@ -15,7 +15,7 @@ import (
 
 func newTestGuard(status connStatusFunc) *Guard {
 	srw := NewSRWatcher(nil, nil, nil, ice.Config{})
-	return NewGuard(log.WithField("test", "guard"), status, 50*time.Millisecond, srw)
+	return NewGuard(log.WithField("test", "guard"), status, 50*time.Millisecond, srw, nil)
 }
 
 // countBackoffTickerGoroutines returns how many goroutines are currently sitting

client/internal/peer/guard/guard_netstate_test.go

@@ -0,0 +1,107 @@
+package guard
+
+import (
+	"context"
+	"sync/atomic"
+	"testing"
+	"time"
+
+	log "github.com/sirupsen/logrus"
+
+	"github.com/netbirdio/netbird/client/internal/peer/ice"
+	"github.com/netbirdio/netbird/client/netstate"
+)
+
+// newTestGuardWithNetState builds a guard with a realistic MaxInterval: the
+// backoff must be able to grow well past the outage, as it does in production
+// where the timeout is seconds to minutes.
+func newTestGuardWithNetState(status connStatusFunc, netState *netstate.State) *Guard {
+	srw := NewSRWatcher(nil, nil, nil, ice.Config{})
+	return NewGuard(log.WithField("test", "guard"), status, 30*time.Second, srw, netState)
+}
+
+// TestGuard_RecoversAfterOfflineToOnline covers a peer that stays disconnected
+// across a network outage while neither signal nor relay reports an event —
+// both stayed up, as on a short airplane mode toggle over Wi-Fi.
+//
+// Every tick taken while offline is skipped, but it still advances the
+// exponential backoff, so by the time the network returns the next tick can be
+// tens of seconds away. Without an explicit reaction to the transition the
+// peer waits out that interval for a recovery that could start immediately.
+func TestGuard_RecoversAfterOfflineToOnline(t *testing.T) {
+	netState := netstate.New()
+
+	var attempts atomic.Int32
+	g := newTestGuardWithNetState(func() ConnStatus { return ConnStatusDisconnected }, netState)
+
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+	// Start from the reconnect ticker (800ms initial interval), the state a
+	// peer is in after it loses its connection.
+	go g.Start(ctx, func() { attempts.Add(1) })
+	g.SetRelayedConnDisconnected()
+
+	// Let the backoff climb: 0.8s, 1.6s, 3.2s, 6.4s ... every tick is skipped
+	// while offline, but each one doubles the wait for the next.
+	netState.Set(false)
+	time.Sleep(8 * time.Second)
+
+	offlineAttempts := attempts.Load()
+	if offlineAttempts != 0 {
+		t.Fatalf("callback ran %d times while offline, want 0", offlineAttempts)
+	}
+
+	netState.Set(true)
+
+	// The next organic tick is now several seconds out, so anything within
+	// this window can only come from reacting to the transition itself.
+	pollCtx, stopPolling := context.WithTimeout(ctx, 2*time.Second)
+	defer stopPolling()
+
+	select {
+	case <-pollCtx.Done():
+		t.Fatal("peer was not retried within 2s of the network coming back, " +
+			"with neither a signal nor a relay event to fall back on")
+	case <-pollUntil(pollCtx, func() bool { return attempts.Load() > 0 }):
+	}
+}
+
+// TestGuard_OfflineTransitionDoesNotRetry checks the other direction: going
+// offline must not itself trigger an attempt.
+func TestGuard_OfflineTransitionDoesNotRetry(t *testing.T) {
+	netState := netstate.New()
+
+	var attempts atomic.Int32
+	g := newTestGuardWithNetState(func() ConnStatus { return ConnStatusDisconnected }, netState)
+
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+	go g.Start(ctx, func() { attempts.Add(1) })
+
+	netState.Set(false)
+	time.Sleep(5 * time.Second)
+
+	if got := attempts.Load(); got != 0 {
+		t.Fatalf("callback ran %d times after going offline, want 0", got)
+	}
+}
+
+// pollUntil closes the returned channel once cond holds. It gives up when ctx
+// is done, so the polling goroutine never outlives the test that started it.
+func pollUntil(ctx context.Context, cond func() bool) <-chan struct{} {
+	done := make(chan struct{})
+	go func() {
+		for {
+			if cond() {
+				close(done)
+				return
+			}
+			select {
+			case <-ctx.Done():
+				return
+			case <-time.After(10 * time.Millisecond):
+			}
+		}
+	}()
+	return done
+}

client/internal/peer/listener.go

@@ -1,11 +1,40 @@
 package peer
 
+// ClientState identifies the client connection state delivered via
+// Listener.OnStateChanged.
+type ClientState int
+
+// Client states. The numeric values cross the gomobile boundary (the mobile
+// bindings re-export them as integer constants), so they are a wire format:
+// append new states at the end, never reorder or insert.
+const (
+	ClientStateDisconnected ClientState = iota
+	ClientStateConnected
+	ClientStateConnecting
+	ClientStateDisconnecting
+	// ClientStateNoNetwork is an overlay state: it is never stored as the
+	// last notification, only derived from ClientStateConnecting while the
+	// OS reports no usable network (see notifier.effectiveState).
+	ClientStateNoNetwork
+)
+
 // Listener is a callback type about the NetBird network connection state
 type Listener interface {
+	// OnStateChanged reports every client state transition. New states are
+	// delivered only through this callback; the per-state callbacks below
+	// are kept for compatibility and will be removed once all consumers
+	// have migrated.
+	OnStateChanged(state ClientState)
+
+	// Deprecated: consume OnStateChanged instead.
 	OnConnected()
+	// Deprecated: consume OnStateChanged instead.
 	OnDisconnected()
+	// Deprecated: consume OnStateChanged instead.
 	OnConnecting()
+	// Deprecated: consume OnStateChanged instead.
 	OnDisconnecting()
+
 	OnAddressChanged(string, string)
 	OnPeersListChanged(int)
 }

client/internal/peer/notifier.go

@@ -4,31 +4,64 @@ import (
 	"sync"
 )
 
-const (
-	stateDisconnected = iota
-	stateConnected
-	stateConnecting
-	stateDisconnecting
-)
-
 type notifier struct {
+	// publishLock orders state publication: it is held across computing the
+	// effective state and handing it to the listener, so a transition cannot
+	// overtake a newer one and leave the listener on a stale state.
+	publishLock        sync.Mutex
 	serverStateLock    sync.Mutex
 	listenersLock      sync.Mutex
 	listener           Listener
 	currentClientState bool
-	lastNotification   int
+	lastNotification   ClientState
 	lastNumberOfPeers  int
 	lastFqdnAddress    string
 	lastIPAddress      string
+	networkAvailable   bool
 }
 
 func newNotifier() *notifier {
-	return &notifier{}
+	return &notifier{
+		networkAvailable: true,
+	}
+}
+
+// effectiveState maps the computed state to what listeners should see:
+// while the OS reports no usable network, "Connecting" would be a lie —
+// connection attempts are suspended — so it is reported as NoNetwork.
+// Caller must hold serverStateLock.
+func (n *notifier) effectiveState(state ClientState) ClientState {
+	if !n.networkAvailable && state == ClientStateConnecting {
+		return ClientStateNoNetwork
+	}
+	return state
+}
+
+// setNetworkAvailable records the OS network availability and re-notifies
+// the listener when the flag flips the effective state (Connecting <->
+// NoNetwork).
+func (n *notifier) setNetworkAvailable(available bool) {
+	n.publishLock.Lock()
+	defer n.publishLock.Unlock()
+
+	n.serverStateLock.Lock()
+	if n.networkAvailable == available {
+		n.serverStateLock.Unlock()
+		return
+	}
+	previous := n.effectiveState(n.lastNotification)
+	n.networkAvailable = available
+	current := n.effectiveState(n.lastNotification)
+	n.serverStateLock.Unlock()
+
+	if previous != current {
+		n.notify(current)
+	}
 }
 
 func (n *notifier) setListener(listener Listener) {
 	n.serverStateLock.Lock()
-	lastNotification := n.lastNotification
+	lastNotification := n.effectiveState(n.lastNotification)
 	numOfPeers := n.lastNumberOfPeers
 	fqdnAddress := n.lastFqdnAddress
 	address := n.lastIPAddress
@@ -52,6 +85,9 @@ func (n *notifier) removeListener() {
 }
 
 func (n *notifier) updateServerStates(mgmState bool, signalState bool) {
+	n.publishLock.Lock()
+	defer n.publishLock.Unlock()
+
 	n.serverStateLock.Lock()
 	calculatedState := n.calculateState(mgmState, signalState)
 
@@ -61,43 +97,54 @@ func (n *notifier) updateServerStates(mgmState bool, signalState bool) {
 	}
 
 	n.lastNotification = calculatedState
+	effective := n.effectiveState(calculatedState)
 	n.serverStateLock.Unlock()
 
-	n.notify(calculatedState)
+	n.notify(effective)
 }
 
 func (n *notifier) clientStart() {
+	n.publishLock.Lock()
+	defer n.publishLock.Unlock()
+
 	n.serverStateLock.Lock()
 	n.currentClientState = true
-	n.lastNotification = stateConnecting
+	n.lastNotification = ClientStateConnecting
+	effective := n.effectiveState(ClientStateConnecting)
 	n.serverStateLock.Unlock()
 
-	n.notify(stateConnecting)
+	n.notify(effective)
 }
 
 func (n *notifier) clientStop() {
+	n.publishLock.Lock()
+	defer n.publishLock.Unlock()
+
 	n.serverStateLock.Lock()
 	n.currentClientState = false
-	n.lastNotification = stateDisconnected
+	n.lastNotification = ClientStateDisconnected
 	n.serverStateLock.Unlock()
 
-	n.notify(stateDisconnected)
+	n.notify(ClientStateDisconnected)
 }
 
 func (n *notifier) clientTearDown() {
+	n.publishLock.Lock()
+	defer n.publishLock.Unlock()
+
 	n.serverStateLock.Lock()
 	n.currentClientState = false
-	n.lastNotification = stateDisconnecting
+	n.lastNotification = ClientStateDisconnecting
 	n.serverStateLock.Unlock()
 
-	n.notify(stateDisconnecting)
+	n.notify(ClientStateDisconnecting)
 }
 
-func (n *notifier) isServerStateChanged(newState int) bool {
+func (n *notifier) isServerStateChanged(newState ClientState) bool {
 	return n.lastNotification != newState
 }
 
-func (n *notifier) notify(state int) {
+func (n *notifier) notify(state ClientState) {
 	n.listenersLock.Lock()
 	listener := n.listener
 	n.listenersLock.Unlock()
@@ -109,20 +156,20 @@ func (n *notifier) notify(state int) {
 	notifyListener(listener, state)
 }
 
-func (n *notifier) calculateState(managementConn, signalConn bool) int {
+func (n *notifier) calculateState(managementConn, signalConn bool) ClientState {
 	if managementConn && signalConn {
-		return stateConnected
+		return ClientStateConnected
 	}
 
 	if !managementConn && !signalConn && !n.currentClientState {
-		return stateDisconnected
+		return ClientStateDisconnected
 	}
 
-	if n.lastNotification == stateDisconnecting {
-		return stateDisconnecting
+	if n.lastNotification == ClientStateDisconnecting {
+		return ClientStateDisconnecting
 	}
 
-	return stateConnecting
+	return ClientStateConnecting
 }
 
 func (n *notifier) peerListChanged(numOfPeers int) {
@@ -159,15 +206,19 @@ func (n *notifier) localAddressChanged(fqdn, address string) {
 	listener.OnAddressChanged(fqdn, address)
 }
 
-func notifyListener(l Listener, state int) {
+func notifyListener(l Listener, state ClientState) {
+	// legacy per-state callbacks; NoNetwork is delivered only via
+	// OnStateChanged below
 	switch state {
-	case stateDisconnected:
+	case ClientStateDisconnected:
 		l.OnDisconnected()
-	case stateConnected:
+	case ClientStateConnected:
 		l.OnConnected()
-	case stateConnecting:
+	case ClientStateConnecting:
 		l.OnConnecting()
-	case stateDisconnecting:
+	case ClientStateDisconnecting:
 		l.OnDisconnecting()
 	}
+
+	l.OnStateChanged(state)
 }

client/internal/peer/notifier_concurrent_test.go

@@ -0,0 +1,108 @@
+package peer
+
+import (
+	"sync"
+	"testing"
+	"time"
+)
+
+type recordingListener struct {
+	mu      sync.Mutex
+	states  []ClientState
+	onState func(ClientState)
+}
+
+func (l *recordingListener) OnStateChanged(state ClientState) {
+	l.mu.Lock()
+	l.states = append(l.states, state)
+	hook := l.onState
+	l.mu.Unlock()
+
+	if hook != nil {
+		hook(state)
+	}
+}
+
+func (l *recordingListener) last() (ClientState, bool) {
+	l.mu.Lock()
+	defer l.mu.Unlock()
+	if len(l.states) == 0 {
+		return 0, false
+	}
+	return l.states[len(l.states)-1], true
+}
+
+func (l *recordingListener) snapshot() []ClientState {
+	l.mu.Lock()
+	defer l.mu.Unlock()
+	return append([]ClientState(nil), l.states...)
+}
+
+func (l *recordingListener) OnConnected()                    {}
+func (l *recordingListener) OnDisconnected()                 {}
+func (l *recordingListener) OnConnecting()                   {}
+func (l *recordingListener) OnDisconnecting()                {}
+func (l *recordingListener) OnAddressChanged(string, string) {}
+func (l *recordingListener) OnPeersListChanged(int)          {}
+
+// TestNotifier_ConcurrentAvailabilityFlipOrdersPublication holds the first
+// transition inside the listener callback and flips availability again from
+// another goroutine while it is parked. The second flip must not publish
+// ahead of the one in flight, otherwise the listener ends up on a state the
+// notifier already superseded.
+func TestNotifier_ConcurrentAvailabilityFlipOrdersPublication(t *testing.T) {
+	n := newNotifier()
+	n.currentClientState = true
+	n.lastNotification = ClientStateConnecting
+
+	entered := make(chan struct{})
+	release := make(chan struct{})
+
+	l := &recordingListener{}
+	l.onState = func(state ClientState) {
+		if state != ClientStateNoNetwork {
+			return
+		}
+		l.mu.Lock()
+		l.onState = nil
+		l.mu.Unlock()
+		close(entered)
+		<-release
+	}
+	n.listener = l
+
+	var wg sync.WaitGroup
+	wg.Add(1)
+	go func() {
+		defer wg.Done()
+		n.setNetworkAvailable(false)
+	}()
+
+	<-entered
+
+	flipped := make(chan struct{})
+	go func() {
+		defer close(flipped)
+		n.setNetworkAvailable(true)
+	}()
+
+	select {
+	case <-flipped:
+		t.Fatal("the online transition published while the offline one was " +
+			"still in flight; publication is not serialized")
+	case <-time.After(200 * time.Millisecond):
+	}
+
+	close(release)
+	<-flipped
+	wg.Wait()
+
+	got, ok := l.last()
+	if !ok {
+		t.Fatal("listener never observed a state")
+	}
+	if got != ClientStateConnecting {
+		t.Fatalf("listener holds %v after the network came back, want Connecting; sequence: %v",
+			got, l.snapshot())
+	}
+}

client/internal/peer/notifier_test.go

@@ -6,29 +6,32 @@ import (
 )
 
 type mocListener struct {
-	lastState int
+	lastState ClientState
 	wg        sync.WaitGroup
 	peersWg   sync.WaitGroup
 	peers     int
 }
 
 func (l *mocListener) OnConnected() {
-	l.lastState = stateConnected
+	l.lastState = ClientStateConnected
 	l.wg.Done()
 }
 func (l *mocListener) OnDisconnected() {
-	l.lastState = stateDisconnected
+	l.lastState = ClientStateDisconnected
 	l.wg.Done()
 }
 func (l *mocListener) OnConnecting() {
-	l.lastState = stateConnecting
+	l.lastState = ClientStateConnecting
 	l.wg.Done()
 }
 func (l *mocListener) OnDisconnecting() {
-	l.lastState = stateDisconnecting
+	l.lastState = ClientStateDisconnecting
 	l.wg.Done()
 }
 
+func (l *mocListener) OnStateChanged(state ClientState) {
+
+}
 func (l *mocListener) OnAddressChanged(host, addr string) {
 
 }
@@ -57,15 +60,15 @@ func Test_notifier_serverState(t *testing.T) {
 
 	type scenario struct {
 		name        string
-		expected    int
+		expected    ClientState
 		mgmState    bool
 		signalState bool
 	}
 	scenarios := []scenario{
-		{"connected", stateConnected, true, true},
-		{"mgm down", stateConnecting, false, true},
-		{"signal down", stateConnecting, true, false},
-		{"disconnected", stateDisconnected, false, false},
+		{"connected", ClientStateConnected, true, true},
+		{"mgm down", ClientStateConnecting, false, true},
+		{"signal down", ClientStateConnecting, true, false},
+		{"disconnected", ClientStateDisconnected, false, false},
 	}
 
 	for _, tt := range scenarios {
@@ -85,7 +88,7 @@ func Test_notifier_SetListener(t *testing.T) {
 	listener.setPeersWaiter()
 
 	n := newNotifier()
-	n.lastNotification = stateConnecting
+	n.lastNotification = ClientStateConnecting
 	n.setListener(listener)
 	listener.wait()
 	listener.waitPeers()
@@ -99,7 +102,7 @@ func Test_notifier_RemoveListener(t *testing.T) {
 	listener.setWaiter()
 	listener.setPeersWaiter()
 	n := newNotifier()
-	n.lastNotification = stateConnecting
+	n.lastNotification = ClientStateConnecting
 	n.setListener(listener)
 	// setListener replays cached state on a goroutine; wait for both the state
 	// and peers callbacks to finish so we don't race on listener.peers.

client/internal/peer/status.go

@@ -1211,6 +1211,12 @@ func (d *Status) ClientTeardown() {
 	d.notifyStateChange()
 }
 
+// SetNetworkAvailable records the OS-reported network availability; while
+// unavailable, listeners see NoNetwork instead of Connecting.
+func (d *Status) SetNetworkAvailable(available bool) {
+	d.notifier.setNetworkAvailable(available)
+}
+
 // SetConnectionListener set a listener to the notifier
 func (d *Status) SetConnectionListener(listener Listener) {
 	d.notifier.setListener(listener)

client/internal/peer/worker_ice.go

@@ -255,8 +255,8 @@ func (w *WorkerICE) connect(ctx context.Context, agent *icemaker.ThreadSafeAgent
 		return
 	}
 
-	w.log.Debugf("turn agent dial")
-	remoteConn, err := w.turnAgentDial(ctx, agent, remoteOfferAnswer)
+	w.log.Debugf("agent dial")
+	remoteConn, err := w.agentDial(ctx, agent, remoteOfferAnswer)
 	if err != nil {
 		w.log.Debugf("failed to dial the remote peer: %s", err)
 		w.closeAgent(agent, w.agentDialerCancel)
@@ -517,8 +517,8 @@ func (w *WorkerICE) onConnectionStateChange(agent *icemaker.ThreadSafeAgent, dia
 			w.logSuccessfulPaths(agent)
 			return
 		case ice.ConnectionStateFailed, ice.ConnectionStateDisconnected, ice.ConnectionStateClosed:
-			// ice.ConnectionStateClosed happens when we recreate the agent. For the P2P to TURN switch important to
-			// notify the conn.onICEStateDisconnected changes to update the current used priority
+			// ice.ConnectionStateClosed happens when we recreate the agent. The P2P to relay switch requires
+			// notifying conn.onICEStateDisconnected so it can update the currently used priority.
 
 			sessionChanged := w.closeAgent(agent, dialerCancel)
 
@@ -532,7 +532,7 @@ func (w *WorkerICE) onConnectionStateChange(agent *icemaker.ThreadSafeAgent, dia
 	}
 }
 
-func (w *WorkerICE) turnAgentDial(ctx context.Context, agent *icemaker.ThreadSafeAgent, remoteOfferAnswer *OfferAnswer) (*ice.Conn, error) {
+func (w *WorkerICE) agentDial(ctx context.Context, agent *icemaker.ThreadSafeAgent, remoteOfferAnswer *OfferAnswer) (*ice.Conn, error) {
 	if isController(w.config) {
 		return agent.Dial(ctx, remoteOfferAnswer.IceCredentials.UFrag, remoteOfferAnswer.IceCredentials.Pwd)
 	} else {

client/internal/profilemanager/prefs.go

@@ -0,0 +1,130 @@
+package profilemanager
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"os"
+	"path/filepath"
+	"sync"
+
+	"github.com/netbirdio/netbird/util"
+)
+
+const prefsFileSuffix = ".prefs.json"
+
+var prefsMu sync.Mutex
+
+// Prefs is a namespaced per-profile preference store backed by a single JSON
+// file next to the profile config; it is deleted together with the profile.
+type Prefs struct {
+	path string
+}
+
+// ProfilePrefs returns the preference store of the profile identified by id.
+func (s *ServiceManager) ProfilePrefs(id ID, username string) (*Prefs, error) {
+	if !IsValidProfileFilenameStem(id) {
+		return nil, fmt.Errorf("invalid profile ID: %q", id)
+	}
+	if id == defaultProfileName {
+		return &Prefs{path: filepath.Join(filepath.Dir(DefaultConfigPath), id.String()+prefsFileSuffix)}, nil
+	}
+	configDir, err := s.getConfigDir(username)
+	if err != nil {
+		return nil, fmt.Errorf("get config directory for user %s: %w", username, err)
+	}
+	return &Prefs{path: filepath.Join(configDir, id.String()+prefsFileSuffix)}, nil
+}
+
+// Get unmarshals the namespace section into v and reports whether it exists.
+func (p *Prefs) Get(namespace string, v any) (bool, error) {
+	if namespace == "" {
+		return false, fmt.Errorf("empty prefs namespace")
+	}
+
+	prefsMu.Lock()
+	defer prefsMu.Unlock()
+
+	sections, err := readPrefsFile(p.path)
+	if err != nil {
+		return false, err
+	}
+	raw, ok := sections[namespace]
+	if !ok {
+		return false, nil
+	}
+	if err := json.Unmarshal(raw, v); err != nil {
+		return false, fmt.Errorf("decode prefs namespace %q: %w", namespace, err)
+	}
+	return true, nil
+}
+
+// Put stores v as the namespace section, replacing any previous value.
+func (p *Prefs) Put(namespace string, v any) error {
+	if namespace == "" {
+		return fmt.Errorf("empty prefs namespace")
+	}
+	raw, err := json.Marshal(v)
+	if err != nil {
+		return fmt.Errorf("encode prefs namespace %q: %w", namespace, err)
+	}
+
+	prefsMu.Lock()
+	defer prefsMu.Unlock()
+
+	sections, err := readPrefsFile(p.path)
+	if err != nil {
+		return err
+	}
+	sections[namespace] = raw
+	return writePrefsFile(p.path, sections)
+}
+
+// Remove deletes the namespace section; a missing one is not an error.
+func (p *Prefs) Remove(namespace string) error {
+	if namespace == "" {
+		return fmt.Errorf("empty prefs namespace")
+	}
+
+	prefsMu.Lock()
+	defer prefsMu.Unlock()
+
+	sections, err := readPrefsFile(p.path)
+	if err != nil {
+		return err
+	}
+	if _, ok := sections[namespace]; !ok {
+		return nil
+	}
+	delete(sections, namespace)
+	return writePrefsFile(p.path, sections)
+}
+
+func removePrefsFile(path string) error {
+	prefsMu.Lock()
+	defer prefsMu.Unlock()
+	return os.Remove(path)
+}
+
+func readPrefsFile(path string) (map[string]json.RawMessage, error) {
+	data, err := os.ReadFile(path)
+	if os.IsNotExist(err) {
+		return map[string]json.RawMessage{}, nil
+	}
+	if err != nil {
+		return nil, fmt.Errorf("read prefs: %w", err)
+	}
+
+	sections := map[string]json.RawMessage{}
+	if err := json.Unmarshal(data, &sections); err != nil {
+		return nil, fmt.Errorf("decode prefs: %w", err)
+	}
+	return sections, nil
+}
+
+func writePrefsFile(path string, sections map[string]json.RawMessage) error {
+	if err := util.WriteJsonWithRestrictedPermission(context.Background(), path, sections); err != nil {
+		return fmt.Errorf("write prefs: %w", err)
+	}
+	return nil
+}

client/internal/profilemanager/prefs_test.go

@@ -0,0 +1,138 @@
+package profilemanager
+
+import (
+	"errors"
+	"os"
+	"path/filepath"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+type testPrefsSection struct {
+	Mode uint8  `json:"mode"`
+	Dest string `json:"dest"`
+}
+
+func TestProfilePrefs_RoundTrip(t *testing.T) {
+	withTestSM(t, func(sm *ServiceManager, username string) {
+		created, err := sm.AddProfile("work", username)
+		require.NoError(t, err)
+
+		prefs, err := sm.ProfilePrefs(created.ID, username)
+		require.NoError(t, err)
+
+		require.NoError(t, prefs.Put("filedrop", testPrefsSection{Mode: 2, Dest: "/tmp/x"}))
+		require.NoError(t, prefs.Put("other", map[string]int{"n": 1}))
+
+		var got testPrefsSection
+		found, err := prefs.Get("filedrop", &got)
+		require.NoError(t, err)
+		assert.True(t, found)
+		assert.Equal(t, testPrefsSection{Mode: 2, Dest: "/tmp/x"}, got)
+
+		var other map[string]int
+		found, err = prefs.Get("other", &other)
+		require.NoError(t, err)
+		assert.True(t, found)
+		assert.Equal(t, map[string]int{"n": 1}, other)
+	})
+}
+
+func TestProfilePrefs_GetMissingNamespace(t *testing.T) {
+	withTestSM(t, func(sm *ServiceManager, username string) {
+		created, err := sm.AddProfile("work", username)
+		require.NoError(t, err)
+
+		prefs, err := sm.ProfilePrefs(created.ID, username)
+		require.NoError(t, err)
+
+		var got testPrefsSection
+		found, err := prefs.Get("filedrop", &got)
+		require.NoError(t, err)
+		assert.False(t, found)
+	})
+}
+
+func TestProfilePrefs_RemoveNamespace(t *testing.T) {
+	withTestSM(t, func(sm *ServiceManager, username string) {
+		created, err := sm.AddProfile("work", username)
+		require.NoError(t, err)
+
+		prefs, err := sm.ProfilePrefs(created.ID, username)
+		require.NoError(t, err)
+
+		require.NoError(t, prefs.Put("filedrop", testPrefsSection{Mode: 1}))
+		require.NoError(t, prefs.Put("other", map[string]int{"n": 1}))
+		require.NoError(t, prefs.Remove("filedrop"))
+		require.NoError(t, prefs.Remove("missing"))
+
+		var got testPrefsSection
+		found, err := prefs.Get("filedrop", &got)
+		require.NoError(t, err)
+		assert.False(t, found)
+
+		var other map[string]int
+		found, err = prefs.Get("other", &other)
+		require.NoError(t, err)
+		assert.True(t, found)
+		assert.Equal(t, map[string]int{"n": 1}, other)
+	})
+}
+
+func TestProfilePrefs_RejectsInvalidID(t *testing.T) {
+	withTestSM(t, func(sm *ServiceManager, username string) {
+		_, err := sm.ProfilePrefs("../escape", username)
+		assert.Error(t, err)
+	})
+}
+
+func TestProfilePrefs_RejectsEmptyNamespace(t *testing.T) {
+	withTestSM(t, func(sm *ServiceManager, username string) {
+		created, err := sm.AddProfile("work", username)
+		require.NoError(t, err)
+
+		prefs, err := sm.ProfilePrefs(created.ID, username)
+		require.NoError(t, err)
+
+		_, err = prefs.Get("", &testPrefsSection{})
+		assert.Error(t, err)
+		assert.Error(t, prefs.Put("", testPrefsSection{}))
+		assert.Error(t, prefs.Remove(""))
+	})
+}
+
+func TestProfilePrefs_DefaultProfile(t *testing.T) {
+	withTestSM(t, func(sm *ServiceManager, username string) {
+		prefs, err := sm.ProfilePrefs(defaultProfileName, username)
+		require.NoError(t, err)
+
+		require.NoError(t, prefs.Put("filedrop", testPrefsSection{Mode: 1}))
+
+		expected := filepath.Join(filepath.Dir(DefaultConfigPath), "default"+prefsFileSuffix)
+		_, err = os.Stat(expected)
+		require.NoError(t, err)
+	})
+}
+
+func TestRemoveProfile_DeletesPrefsFile(t *testing.T) {
+	withTestSM(t, func(sm *ServiceManager, username string) {
+		created, err := sm.AddProfile("work", username)
+		require.NoError(t, err)
+
+		prefs, err := sm.ProfilePrefs(created.ID, username)
+		require.NoError(t, err)
+		require.NoError(t, prefs.Put("filedrop", testPrefsSection{Mode: 2}))
+
+		configDir, err := sm.getConfigDir(username)
+		require.NoError(t, err)
+		prefsPath := filepath.Join(configDir, created.ID.String()+prefsFileSuffix)
+		_, err = os.Stat(prefsPath)
+		require.NoError(t, err)
+
+		require.NoError(t, sm.RemoveProfile(created.ID, username))
+		_, err = os.Stat(prefsPath)
+		assert.True(t, errors.Is(err, os.ErrNotExist), "prefs file should be removed")
+	})
+}

client/internal/profilemanager/service.go

@@ -420,6 +420,11 @@ func (s *ServiceManager) RemoveProfile(id ID, username string) error {
 		log.Warnf("failed to remove profile state file %s: %v", stateFile, err)
 	}
 
+	prefsFile := filepath.Join(filepath.Dir(target.Path), id.String()+prefsFileSuffix)
+	if err := removePrefsFile(prefsFile); err != nil && !os.IsNotExist(err) {
+		log.Warnf("failed to remove profile prefs file %s: %v", prefsFile, err)
+	}
+
 	return nil
 }
 

client/internal/sleep/service.go

@@ -18,8 +18,8 @@ type Service struct {
 }
 
 func New() (*Service, error) {
-	d, err := NewDetector()
-	if err != nil {
+	d, err := NewDetector() //nolint:staticcheck
+	if err != nil {         //nolint:staticcheck // always errors on platforms without a sleep detector
 		return nil, err
 	}
 

client/internal/updater/installer/doc.go

@@ -37,23 +37,32 @@
 // Updater Process (Setup):
 //
 //  1. Receives parameters from service via command-line arguments
-//  2. Runs installer with appropriate silent/quiet flags:
+//  2. Terminates the UI so the installer does not have to replace a locked image
+//     file, which would otherwise leave the install needing a reboot
+//  3. Runs installer with appropriate silent/quiet flags:
 //     - Windows EXE: installer.exe /S
-//     - Windows MSI: msiexec.exe /i installer.msi /quiet /qn /l*v msi.log
+//     - Windows MSI: msiexec.exe /i installer.msi /qn /norestart REBOOT=ReallySuppress /l*v msi.log
 //     - macOS PKG: installer -pkg installer.pkg -target /
 //     - macOS Homebrew: brew upgrade netbirdio/tap/netbird
-//  3. Installer terminates daemon and UI processes
-//  4. Installer replaces binaries with new version
-//  5. Updater waits for installer to complete
-//  6. Updater restarts daemon:
+//  4. Installer terminates the daemon
+//  5. Installer replaces binaries with new version
+//  6. Updater waits for installer to complete. On Windows, MSI exit codes 3010
+//     (ERROR_SUCCESS_REBOOT_REQUIRED) and 1641 (ERROR_SUCCESS_REBOOT_INITIATED)
+//     are a pending-reboot outcome, not a failure: the install succeeded, but
+//     some files are only replaced on the next restart (the reboot itself is
+//     suppressed via /norestart and REBOOT=ReallySuppress), and the flow
+//     continues as on success
+//  7. Updater restarts daemon:
 //     - Windows: netbird.exe service start
 //     - macOS/Linux: netbird service start
-//  7. Updater restarts UI:
-//     - Windows: Launches netbird-ui.exe as active console user using CreateProcessAsUser
+//  8. Updater restarts UI:
+//     - Windows: Launches netbird-ui.exe using CreateProcessAsUser in every
+//     session it was terminated in, falling back to the active console session
 //     - macOS: Uses launchctl asuser to launch NetBird.app for console user
 //     - Linux: Not implemented (UI typically auto-starts)
-//  8. Updater writes result.json with success/error status
-//  9. Updater process exits
+//  9. Updater writes result.json with success/error status (a pending reboot is
+//     recorded as success)
+//  10. Updater process exits
 //
 // # Result Communication
 //

client/internal/updater/installer/installer_common.go

@@ -42,6 +42,9 @@ func NewWithDir(tempDir string) *Installer {
 // This will run by the original service process
 func (u *Installer) RunInstallation(ctx context.Context, targetVersion string) (err error) {
 	resultHandler := NewResultHandler(u.tempDir)
+	if err := resultHandler.ClearStaleResult(); err != nil {
+		log.Warnf("clear stale installer result: %v", err)
+	}
 
 	defer func() {
 		if err != nil {

client/internal/updater/installer/installer_run_windows.go

@@ -2,6 +2,7 @@ package installer
 
 import (
 	"context"
+	"errors"
 	"fmt"
 	"os"
 	"os/exec"
@@ -22,6 +23,12 @@ const (
 
 	msiLogFile = "msi.log"
 
+	// ERROR_SUCCESS_REBOOT_REQUIRED and ERROR_SUCCESS_REBOOT_INITIATED
+	msiRebootRequired  = 3010
+	msiRebootInitiated = 1641
+
+	processExitWait = 10 * time.Second
+
 	msiDownloadURL = "https://github.com/netbirdio/netbird/releases/download/v%version/netbird_installer_%version_windows_%arch.msi"
 	exeDownloadURL = "https://github.com/netbirdio/netbird/releases/download/v%version/netbird_installer_%version_windows_%arch.exe"
 )
@@ -38,6 +45,8 @@ var (
 func (u *Installer) Setup(ctx context.Context, dryRun bool, installerFile string, daemonFolder string) (resultErr error) {
 	resultHandler := NewResultHandler(u.tempDir)
 
+	var uiSessions []uint32
+
 	// Always ensure daemon and UI are restarted after setup
 	defer func() {
 		log.Infof("starting daemon back")
@@ -46,7 +55,7 @@ func (u *Installer) Setup(ctx context.Context, dryRun bool, installerFile string
 		}
 
 		log.Infof("starting UI back")
-		if err := u.startUIAsUser(daemonFolder); err != nil {
+		if err := u.startUI(daemonFolder, uiSessions); err != nil {
 			log.Errorf("failed to start UI: %v", err)
 		}
 
@@ -75,6 +84,14 @@ func (u *Installer) Setup(ctx context.Context, dryRun bool, installerFile string
 		return
 	}
 
+	// The UI holds an open handle on its own image. Left running, Restart Manager
+	// cannot shut it down (msiexec runs as LocalSystem here, the UI as the
+	// interactive user), so the MSI falls back to replacing the file on reboot and
+	// marks the install as restart-required. The deferred close-application action
+	// in the package runs too late to prevent that, it happens after
+	// InstallValidate has already registered the file as in use.
+	uiSessions = killUI()
+
 	var cmd *exec.Cmd
 	switch installerType {
 	case TypeExe:
@@ -84,7 +101,9 @@ func (u *Installer) Setup(ctx context.Context, dryRun bool, installerFile string
 		installerDir := filepath.Dir(installerFile)
 		logPath := filepath.Join(installerDir, msiLogFile)
 		log.Infof("run msi installer: %s", installerFile)
-		cmd = exec.CommandContext(ctx, "msiexec.exe", "/i", filepath.Base(installerFile), "/quiet", "/qn", "/l*v", logPath)
+		// REBOOT=ReallySuppress: a silent install has no way to ask, so without it
+		// msiexec reboots the machine on its own if it decides one is needed.
+		cmd = exec.CommandContext(ctx, "msiexec.exe", "/i", filepath.Base(installerFile), "/qn", "/norestart", "REBOOT=ReallySuppress", "/l*v", logPath)
 	}
 
 	cmd.Dir = filepath.Dir(installerFile)
@@ -95,9 +114,13 @@ func (u *Installer) Setup(ctx context.Context, dryRun bool, installerFile string
 	}
 
 	log.Infof("installer started with PID %d", cmd.Process.Pid)
-	if resultErr = cmd.Wait(); resultErr != nil {
-		log.Errorf("installer process finished with error: %v", resultErr)
-		return
+	if err := cmd.Wait(); err != nil {
+		if !isRebootPending(err) {
+			resultErr = err
+			log.Errorf("installer process finished with error: %v", err)
+			return
+		}
+		log.Warnf("installer completed but reported a pending reboot, some files will be replaced on the next restart")
 	}
 
 	return nil
@@ -117,16 +140,142 @@ func (u *Installer) startDaemon(daemonFolder string) error {
 	return nil
 }
 
-func (u *Installer) startUIAsUser(daemonFolder string) error {
+func (u *Installer) startUI(daemonFolder string, sessionIDs []uint32) error {
 	uiPath := filepath.Join(daemonFolder, uiName)
 	log.Infof("starting netbird-ui: %s", uiPath)
 
-	// Get the active console session ID
-	sessionID := windows.WTSGetActiveConsoleSessionId()
-	if sessionID == 0xFFFFFFFF {
-		return fmt.Errorf("no active user session found")
+	if len(sessionIDs) == 0 {
+		sessionID := windows.WTSGetActiveConsoleSessionId()
+		if sessionID == 0xFFFFFFFF {
+			return fmt.Errorf("no active user session found")
+		}
+		sessionIDs = []uint32{sessionID}
 	}
 
+	var errs []error
+	for _, sessionID := range sessionIDs {
+		if err := startUIInSession(uiPath, sessionID); err != nil {
+			errs = append(errs, fmt.Errorf("session %d: %w", sessionID, err))
+			continue
+		}
+		log.Infof("netbird-ui started successfully in session %d", sessionID)
+	}
+	return errors.Join(errs...)
+}
+
+// isRebootPending reports whether the installer exit code means it succeeded but
+// left work for the next restart. The reboot itself is suppressed, so this is not
+// a failure.
+func isRebootPending(err error) bool {
+	var exitErr *exec.ExitError
+	if !errors.As(err, &exitErr) {
+		return false
+	}
+
+	switch exitErr.ExitCode() {
+	case msiRebootRequired, msiRebootInitiated:
+		return true
+	default:
+		return false
+	}
+}
+
+// killUI terminates any running netbird-ui process and returns the IDs of the
+// interactive sessions the terminated processes belonged to. Setup starts the
+// UI again in those sessions once the installer is done.
+func killUI() []uint32 {
+	pids, err := processIDsByName(uiName)
+	if err != nil {
+		log.Warnf("failed to look up %s processes: %v", uiName, err)
+		return nil
+	}
+
+	sessions := make(map[uint32]struct{})
+	for _, pid := range pids {
+		var sessionID uint32
+		if err := windows.ProcessIdToSessionId(pid, &sessionID); err != nil {
+			log.Warnf("failed to look up session of %s (PID %d): %v", uiName, pid, err)
+		}
+
+		if err := terminateProcess(pid); err != nil {
+			log.Warnf("failed to terminate %s (PID %d): %v", uiName, pid, err)
+			continue
+		}
+		log.Infof("terminated %s (PID %d) in session %d", uiName, pid, sessionID)
+
+		if sessionID != 0 {
+			sessions[sessionID] = struct{}{}
+		}
+	}
+
+	sessionIDs := make([]uint32, 0, len(sessions))
+	for sessionID := range sessions {
+		sessionIDs = append(sessionIDs, sessionID)
+	}
+	return sessionIDs
+}
+
+func processIDsByName(name string) ([]uint32, error) {
+	snapshot, err := windows.CreateToolhelp32Snapshot(windows.TH32CS_SNAPPROCESS, 0)
+	if err != nil {
+		return nil, fmt.Errorf("create process snapshot: %w", err)
+	}
+	defer func() {
+		if err := windows.CloseHandle(snapshot); err != nil {
+			log.Warnf("failed to close process snapshot: %v", err)
+		}
+	}()
+
+	var entry windows.ProcessEntry32
+	entry.Size = uint32(unsafe.Sizeof(entry))
+
+	var pids []uint32
+	for err = windows.Process32First(snapshot, &entry); err == nil; err = windows.Process32Next(snapshot, &entry) {
+		if strings.EqualFold(windows.UTF16ToString(entry.ExeFile[:]), name) {
+			pids = append(pids, entry.ProcessID)
+		}
+	}
+	if !errors.Is(err, windows.ERROR_NO_MORE_FILES) {
+		return nil, fmt.Errorf("enumerate processes: %w", err)
+	}
+
+	return pids, nil
+}
+
+func terminateProcess(pid uint32) error {
+	handle, err := windows.OpenProcess(windows.PROCESS_TERMINATE|windows.SYNCHRONIZE, false, pid)
+	if err != nil {
+		// The process may have exited between enumeration and now.
+		if errors.Is(err, windows.ERROR_INVALID_PARAMETER) {
+			return nil
+		}
+		return fmt.Errorf("open process: %w", err)
+	}
+	defer func() {
+		if err := windows.CloseHandle(handle); err != nil {
+			log.Warnf("failed to close process handle: %v", err)
+		}
+	}()
+
+	if err := windows.TerminateProcess(handle, 0); err != nil {
+		return fmt.Errorf("terminate process: %w", err)
+	}
+
+	// Wait for the handle to signal so the image file is released before the
+	// installer tries to overwrite it. A timeout is reported through the returned
+	// event, not through err, which stays nil unless the wait itself failed.
+	event, err := windows.WaitForSingleObject(handle, uint32(processExitWait.Milliseconds()))
+	if err != nil {
+		return fmt.Errorf("wait for process exit: %w", err)
+	}
+	if event != windows.WAIT_OBJECT_0 {
+		return fmt.Errorf("wait for process exit: unexpected wait result %#x", event)
+	}
+
+	return nil
+}
+
+func startUIInSession(uiPath string, sessionID uint32) error {
 	// Get the user token for that session
 	var userToken windows.Token
 	err := windows.WTSQueryUserToken(sessionID, &userToken)
@@ -158,6 +307,16 @@ func (u *Installer) startUIAsUser(daemonFolder string) error {
 		}
 	}()
 
+	var env *uint16
+	if err := windows.CreateEnvironmentBlock(&env, primaryToken, false); err != nil {
+		return fmt.Errorf("create environment block: %w", err)
+	}
+	defer func() {
+		if err := windows.DestroyEnvironmentBlock(env); err != nil {
+			log.Warnf("failed to destroy environment block: %v", err)
+		}
+	}()
+
 	// Prepare startup info
 	var si windows.StartupInfo
 	si.Cb = uint32(unsafe.Sizeof(si))
@@ -180,7 +339,7 @@ func (u *Installer) startUIAsUser(daemonFolder string) error {
 		nil,
 		false,
 		creationFlags,
-		nil,
+		env,
 		nil,
 		&si,
 		&pi,
@@ -197,7 +356,6 @@ func (u *Installer) startUIAsUser(daemonFolder string) error {
 		log.Warnf("failed to close thread handle: %v", err)
 	}
 
-	log.Infof("netbird-ui started successfully in session %d", sessionID)
 	return nil
 }
 

client/internal/updater/installer/installer_run_windows_test.go

@@ -0,0 +1,108 @@
+package installer
+
+import (
+	"errors"
+	"os/exec"
+	"slices"
+	"strconv"
+	"testing"
+)
+
+// exitErrorWithCode returns a real *exec.ExitError carrying the given exit code.
+func exitErrorWithCode(t *testing.T, code int) error {
+	t.Helper()
+
+	err := exec.Command("cmd.exe", "/c", "exit "+strconv.Itoa(code)).Run()
+	if err == nil {
+		t.Fatalf("expected a non-zero exit for code %d", code)
+	}
+	return err
+}
+
+func TestIsRebootPending(t *testing.T) {
+	tests := []struct {
+		name string
+		code int
+		want bool
+	}{
+		{name: "reboot required", code: msiRebootRequired, want: true},
+		{name: "reboot initiated", code: msiRebootInitiated, want: true},
+		{name: "generic failure", code: 1603, want: false},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			if got := isRebootPending(exitErrorWithCode(t, tt.code)); got != tt.want {
+				t.Errorf("isRebootPending(exit %d) = %v, want %v", tt.code, got, tt.want)
+			}
+		})
+	}
+}
+
+// TestProcessIDsByNameAndTerminate spawns a long-running system process, finds it
+// by name and terminates it, covering the path the updater uses to release the UI
+// image file before the installer replaces it.
+func TestProcessIDsByNameAndTerminate(t *testing.T) {
+	cmd := exec.Command("ping.exe", "-n", "60", "127.0.0.1")
+	if err := cmd.Start(); err != nil {
+		t.Fatalf("start ping: %v", err)
+	}
+
+	pid := uint32(cmd.Process.Pid)
+	killed := false
+	t.Cleanup(func() {
+		if !killed {
+			_ = cmd.Process.Kill()
+		}
+		_ = cmd.Wait()
+	})
+
+	// Name matching must be case-insensitive: the snapshot reports PING.EXE.
+	pids, err := processIDsByName("ping.exe")
+	if err != nil {
+		t.Fatalf("processIDsByName: %v", err)
+	}
+
+	if !slices.Contains(pids, pid) {
+		t.Fatalf("PID %d not among the ping.exe processes found: %v", pid, pids)
+	}
+
+	if err := terminateProcess(pid); err != nil {
+		t.Fatalf("terminateProcess: %v", err)
+	}
+	killed = true
+
+	// terminateProcess only returns once the handle has signalled, so the process
+	// is already gone and Wait must not block. It exits with the code passed to
+	// TerminateProcess, which is 0, so Wait reports no error.
+	if err := cmd.Wait(); err != nil {
+		t.Fatalf("wait for terminated ping: %v", err)
+	}
+	if !cmd.ProcessState.Exited() {
+		t.Error("process did not exit after terminateProcess")
+	}
+
+	remaining, err := processIDsByName("ping.exe")
+	if err != nil {
+		t.Fatalf("processIDsByName after terminate: %v", err)
+	}
+	if slices.Contains(remaining, pid) {
+		t.Errorf("PID %d still listed after terminateProcess", pid)
+	}
+}
+
+func TestProcessIDsByNameNoMatch(t *testing.T) {
+	pids, err := processIDsByName("netbird-nonexistent-process.exe")
+	if err != nil {
+		t.Fatalf("processIDsByName: %v", err)
+	}
+	if len(pids) != 0 {
+		t.Errorf("expected no matches, got %v", pids)
+	}
+}
+
+func TestIsRebootPendingNonExitError(t *testing.T) {
+	if isRebootPending(errors.New("start installer: file not found")) {
+		t.Error("a non-exit error must not be treated as a pending reboot")
+	}
+}

client/internal/updater/installer/result.go

@@ -54,6 +54,12 @@ func (rh *ResultHandler) GetErrorResultReason() string {
 	return ""
 }
 
+// ClearStaleResult removes a result file left over from a previous installation
+// attempt so result watchers cannot read an outdated outcome for the current attempt.
+func (rh *ResultHandler) ClearStaleResult() error {
+	return rh.cleanup()
+}
+
 func (rh *ResultHandler) WriteSuccess() error {
 	result := Result{
 		Success:    true,

client/internal/updater/manager.go

@@ -435,7 +435,7 @@ func (m *Manager) install(ctx context.Context, pendingVersion *v.Version) error
 	}
 
 	inst := installer.New()
-	if err := inst.RunInstallation(ctx, pendingVersion.String()); err != nil {
+	if err := inst.RunInstallation(ctx, pendingVersion.String()); err != nil { //nolint:staticcheck // always errors on platforms without an installer
 		log.Errorf("error triggering update: %v", err)
 		m.statusRecorder.PublishEvent(
 			cProto.SystemEvent_ERROR,

client/ios/NetBirdSDK/client.go

@@ -22,6 +22,8 @@ import (
 	"github.com/netbirdio/netbird/client/internal/listener"
 	"github.com/netbirdio/netbird/client/internal/peer"
 	"github.com/netbirdio/netbird/client/internal/profilemanager"
+	"github.com/netbirdio/netbird/client/netstate"
+	"github.com/netbirdio/netbird/client/netsweep"
 	"github.com/netbirdio/netbird/client/system"
 	"github.com/netbirdio/netbird/formatter"
 	"github.com/netbirdio/netbird/route"
@@ -36,11 +38,6 @@ const (
 	AnonymizeLevelStrict  = nbAnonymize.LevelStrictString
 )
 
-// ConnectionListener export internal Listener for mobile
-type ConnectionListener interface {
-	peer.Listener
-}
-
 // RouteListener export internal RouteListener for mobile
 type NetworkChangeListener interface {
 	listener.NetworkChangeListener
@@ -87,6 +84,12 @@ type Client struct {
 	onHostDnsFn           func([]string)
 	dnsManager            dns.IosDnsManager
 	loginComplete         bool
+	// netState outlives engine restarts: it mirrors the OS connectivity, not
+	// the engine lifecycle. Run injects it into each new ConnectClient, which
+	// distributes it to every reconnection loop.
+	netState *netstate.State
+	// sweeper also outlives engine restarts; NotifyNetworkChange sweeps it.
+	sweeper *netsweep.Sweeper
 	// preloadedConfig holds config loaded from JSON (used on tvOS where file writes are blocked)
 	preloadedConfig *profilemanager.Config
 
@@ -109,6 +112,8 @@ func NewClient(cfgFile, stateFile, cacheDir, logFilePath, deviceName string, osV
 		ctxCancelLock:         &sync.Mutex{},
 		networkChangeListener: networkChangeListener,
 		dnsManager:            dnsManager,
+		netState:              netstate.New(),
+		sweeper:               netsweep.New(),
 	}
 }
 
@@ -184,7 +189,8 @@ func (c *Client) Run(fd int32, interfaceName string, envList *EnvList) error {
 	c.onHostDnsFn = func([]string) {}
 	cfg.WgIface = interfaceName
 
-	connectClient := internal.NewConnectClient(ctx, cfg, c.recorder)
+	connectClient := internal.NewConnectClient(ctx, cfg, c.recorder,
+		internal.WithNetworkState(c.netState), internal.WithSweeper(c.sweeper))
 	c.setState(cfg, connectClient)
 	// Persist the latest sync response so DebugBundle can include the network
 	// map. On iOS this is backed by disk to keep it out of the constrained
@@ -193,6 +199,25 @@ func (c *Client) Run(fd int32, interfaceName string, envList *EnvList) error {
 	return connectClient.RunOniOS(fd, c.networkChangeListener, c.dnsManager, c.stateFile, c.cacheDir, c.logFilePath)
 }
 
+// SetNetworkAvailable feeds OS-reported network availability into the client
+// (e.g. from NWPathMonitor). While unavailable, the internal reconnect loops
+// suspend their attempts and the connection listener reports NoNetwork
+// instead of Connecting; when availability returns, the loops resume
+// immediately with a fresh backoff.
+func (c *Client) SetNetworkAvailable(available bool) {
+	c.netState.Set(available)
+	c.recorder.SetNetworkAvailable(available)
+}
+
+// NotifyNetworkChange marks the management, signal and relay connections
+// stale after the OS switched networks and schedules a sweep that cuts
+// whatever has not redialed on the new network by then. The engine and the
+// TUN device stay untouched.
+func (c *Client) NotifyNetworkChange() {
+	c.sweeper.MarkNetworkChange()
+	log.Infof("network change: connections marked stale")
+}
+
 // Stop the internal client and free the resources
 func (c *Client) Stop() {
 	c.ctxCancelLock.Lock()
@@ -331,7 +356,11 @@ func (c *Client) GetStatusDetails() *StatusDetails {
 
 // SetConnectionListener set the network connection listener
 func (c *Client) SetConnectionListener(listener ConnectionListener) {
-	c.recorder.SetConnectionListener(listener)
+	if listener == nil {
+		c.recorder.RemoveConnectionListener()
+		return
+	}
+	c.recorder.SetConnectionListener(connectionListenerAdapter{listener})
 }
 
 // RemoveConnectionListener remove connection listener

client/ios/NetBirdSDK/connection_listener.go

@@ -0,0 +1,43 @@
+//go:build ios
+
+package NetBirdSDK
+
+import (
+	"github.com/netbirdio/netbird/client/internal/peer"
+)
+
+// Client state values, re-exported as basic constants so gomobile emits them
+// into the generated bindings. They mirror peer.ClientState*: append-only,
+// never reorder.
+const (
+	ClientStateDisconnected  = int(peer.ClientStateDisconnected)
+	ClientStateConnected     = int(peer.ClientStateConnected)
+	ClientStateConnecting    = int(peer.ClientStateConnecting)
+	ClientStateDisconnecting = int(peer.ClientStateDisconnecting)
+	ClientStateNoNetwork     = int(peer.ClientStateNoNetwork)
+)
+
+// ConnectionListener export internal Listener for mobile.
+//
+// It intentionally lacks OnStateChanged for now: adding a method to a gomobile
+// interface breaks every Swift implementation, so the iOS app keeps building
+// against the legacy per-state callbacks. A follow-up will extend it together
+// with the app.
+type ConnectionListener interface {
+	OnConnected()
+	OnDisconnected()
+	OnConnecting()
+	OnDisconnecting()
+	OnAddressChanged(string, string)
+	OnPeersListChanged(int)
+}
+
+// connectionListenerAdapter adapts the gomobile-facing ConnectionListener to
+// peer.Listener.
+type connectionListenerAdapter struct {
+	ConnectionListener
+}
+
+// OnStateChanged is dropped on iOS until the app adopts the state callback;
+// the legacy per-state callbacks continue to fire.
+func (a connectionListenerAdapter) OnStateChanged(peer.ClientState) {}

client/ios/NetBirdSDK/login.go

@@ -323,7 +323,7 @@ func (a *Auth) login(urlOpener URLOpener, forceDeviceAuth bool, deviceName strin
 const authInfoRequestTimeout = 30 * time.Second
 
 func (a *Auth) foregroundGetTokenInfo(authClient *auth.Auth, urlOpener URLOpener, forceDeviceAuth bool) (*auth.TokenInfo, error) {
-	oAuthFlow, err := authClient.GetOAuthFlow(a.ctx, forceDeviceAuth)
+	oAuthFlow, err := authClient.GetOAuthFlow(a.ctx, forceDeviceAuth, "")
 	if err != nil {
 		return nil, fmt.Errorf("failed to get OAuth flow: %v", err)
 	}

client/netstate/netstate.go

@@ -0,0 +1,110 @@
+// Package netstate tracks OS-reported network availability for the client.
+//
+// A State instance is owned by the platform integration (e.g. the Android or
+// iOS bindings, fed from ConnectivityManager callbacks or NWPathMonitor) and
+// is injected into the connection retry loops (management, signal, relay,
+// peer guards and the top-level connect loop), which consult it to avoid
+// burning CPU and battery on reconnect attempts while the device has no
+// network at all (e.g. airplane mode), and to reset their backoff as soon as
+// the network returns.
+//
+// Consumers hold a *State that may be nil — every non-mobile platform leaves
+// it unset. The read methods are safe on a nil receiver: they report online
+// and never block, so consumers behave as if this package did not exist.
+package netstate
+
+import (
+	"context"
+	"sync"
+
+	log "github.com/sirupsen/logrus"
+)
+
+// State holds the OS-reported network availability. The zero value is not
+// usable; create instances with New.
+type State struct {
+	mu      sync.Mutex
+	online  bool
+	changed chan struct{}
+}
+
+// New creates a State that starts online. Platforms without network tracking
+// pass a nil *State instead: the read methods treat nil as always online and
+// never block, so consumers need no nil guards.
+func New() *State {
+	return &State{
+		online:  true,
+		changed: make(chan struct{}),
+	}
+}
+
+// Set records whether the OS reports any usable network. Transitions wake up
+// all Wait callers immediately. Unlike the read methods, Set is not nil-safe:
+// it is only for the platform owner that created the State with New.
+func (s *State) Set(online bool) {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	if s.online == online {
+		return
+	}
+	s.online = online
+	close(s.changed)
+	s.changed = make(chan struct{})
+	log.Infof("OS network availability changed: online=%t", online)
+}
+
+// IsOnline reports whether the OS reports at least one usable network. On a
+// nil receiver — no State injected — it reports online.
+func (s *State) IsOnline() bool {
+	if s == nil {
+		return true
+	}
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	return s.online
+}
+
+// Changed returns a channel closed on the next availability transition, for
+// callers that already own a select loop and cannot block in Wait. Re-read it
+// after every fire: each transition installs a fresh channel. On a nil
+// receiver — no State injected — it returns nil, which blocks forever in a
+// select, so the caller simply never observes a transition.
+func (s *State) Changed() <-chan struct{} {
+	if s == nil {
+		return nil
+	}
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	return s.changed
+}
+
+// Wait blocks while the network is offline. It reports whether it had to
+// wait, so callers can reset their backoff after an outage. It returns early
+// with the context error when ctx is done. On a nil receiver — no State
+// injected — it returns immediately.
+func (s *State) Wait(ctx context.Context) (bool, error) {
+	if s == nil {
+		return false, nil
+	}
+	waited := false
+	for {
+		s.mu.Lock()
+		if s.online {
+			s.mu.Unlock()
+			return waited, nil
+		}
+		ch := s.changed
+		s.mu.Unlock()
+
+		if !waited {
+			waited = true
+			log.Debugf("network is offline, pausing connection attempts")
+		}
+
+		select {
+		case <-ctx.Done():
+			return waited, ctx.Err()
+		case <-ch:
+		}
+	}
+}