[client] Android - Pull fresh TUN settings on Android rebuild

client/android/client.go

@@ -57,6 +57,12 @@ type DnsReadyListener interface {
 	dns.ReadyListener
 }
 
+// TunSettings is a snapshot of the settings the TUN device is rebuilt with
+type TunSettings struct {
+	Routes        string
+	SearchDomains string
+}
+
 func init() {
 	formatter.SetLogcatFormatter(log.StandardLogger())
 }
@@ -240,6 +246,24 @@ func (c *Client) RenewTun(fd int) error {
 	return e.RenewTun(fd)
 }
 
+func (c *Client) GetTunSettings() (*TunSettings, error) {
+	cc := c.getConnectClient()
+	if cc == nil {
+		return nil, fmt.Errorf("engine not running")
+	}
+
+	e := cc.Engine()
+	if e == nil {
+		return nil, fmt.Errorf("engine not initialized")
+	}
+
+	routes, searchDomains := e.TunSettings()
+	return &TunSettings{
+		Routes:        strings.Join(routes, ";"),
+		SearchDomains: strings.Join(searchDomains, ";"),
+	}, nil
+}
+
 // DebugBundle generates a debug bundle, uploads it, and returns the upload key.
 // It works both with and without a running engine.
 func (c *Client) DebugBundle(platformFiles PlatformFiles, anonymize bool) (string, error) {

client/internal/dns/server.go

@@ -252,7 +252,7 @@ func NewDefaultServerPermanentUpstream(
 	ds.hostsDNSHolder.set(hostsDnsList)
 	ds.permanent = true
 	ds.currentConfig = dnsConfigToHostDNSConfig(config, ds.service.RuntimeIP(), ds.service.RuntimePort())
-	ds.searchDomainNotifier = newNotifier(ds.SearchDomains())
+	ds.searchDomainNotifier = newNotifier(ds.searchDomains())
 	ds.searchDomainNotifier.setListener(listener)
 	setServerDns(ds)
 	return ds
@@ -602,6 +602,12 @@ func (s *DefaultServer) UpdateDNSServer(serial uint64, update nbdns.Config) erro
 }
 
 func (s *DefaultServer) SearchDomains() []string {
+	s.mux.Lock()
+	defer s.mux.Unlock()
+	return s.searchDomains()
+}
+
+func (s *DefaultServer) searchDomains() []string {
 	var searchDomains []string
 
 	for _, dConf := range s.currentConfig.Domains {
@@ -686,7 +692,7 @@ func (s *DefaultServer) applyConfiguration(update nbdns.Config) error {
 	}()
 
 	if s.searchDomainNotifier != nil {
-		s.searchDomainNotifier.onNewSearchDomains(s.SearchDomains())
+		s.searchDomainNotifier.onNewSearchDomains(s.searchDomains())
 	}
 
 	s.updateNSGroupStates(update.NameServerGroups)

client/internal/engine_tunsettings.go

@@ -0,0 +1,20 @@
+package internal
+
+func (e *Engine) TunSettings() ([]string, []string) {
+	e.syncMsgMux.Lock()
+	routeManager := e.routeManager
+	dnsServer := e.dnsServer
+	e.syncMsgMux.Unlock()
+
+	var routes []string
+	if routeManager != nil {
+		routes = routeManager.CurrentRouteRange()
+	}
+
+	var searchDomains []string
+	if dnsServer != nil {
+		searchDomains = dnsServer.SearchDomains()
+	}
+
+	return routes, searchDomains
+}

client/internal/routemanager/manager.go

@@ -9,6 +9,7 @@ import (
 	"net/url"
 	"runtime"
 	"slices"
+	"sort"
 	"strings"
 	"sync"
 	"sync/atomic"
@@ -63,6 +64,7 @@ type Manager interface {
 	GetClientRoutesWithNetID() map[route.NetID][]*route.Route
 	SetRouteChangeListener(listener listener.NetworkChangeListener)
 	InitialRouteRange() []string
+	CurrentRouteRange() []string
 	SetFirewall(firewall.Manager) error
 	SetDNSForwarderPort(port uint16)
 	ReconcilePeerAllowedIPs(peerKey string) error
@@ -191,7 +193,7 @@ func (m *DefaultManager) enableFakeIPRoutes() []*route.Route {
 		NetworkType: route.IPv6Network,
 	}
 	fakeRoutes := []*route.Route{fakeIPRoute, fakeIPv6Route}
-	m.notifier.SetFakeIPRoutes(fakeRoutes)
+	m.notifier.NotifyRouteChange()
 	return fakeRoutes
 }
 
@@ -513,6 +515,34 @@ func (m *DefaultManager) InitialRouteRange() []string {
 	return m.notifier.GetInitialRouteRanges()
 }
 
+// CurrentRouteRange returns the current TUN route list. It is used by mobile systems
+func (m *DefaultManager) CurrentRouteRange() []string {
+	m.mux.Lock()
+	defer m.mux.Unlock()
+
+	if m.disableClientRoutes {
+		return nil
+	}
+
+	filtered := m.routeSelector.FilterSelectedExitNodes(m.clientRoutes)
+	var nets []string
+	for _, routes := range filtered {
+		for _, r := range routes {
+			if r.IsDynamic() {
+				continue
+			}
+			nets = append(nets, r.NetString())
+		}
+	}
+
+	if m.fakeIPManager != nil {
+		nets = append(nets, m.fakeIPManager.GetFakeIPBlock().String(), m.fakeIPManager.GetFakeIPv6Block().String())
+	}
+
+	sort.Strings(nets)
+	return nets
+}
+
 // GetRouteSelector returns the route selector
 func (m *DefaultManager) GetRouteSelector() *routeselector.RouteSelector {
 	return m.routeSelector

client/internal/routemanager/mock.go

@@ -35,6 +35,11 @@ func (m *MockManager) InitialRouteRange() []string {
 	return nil
 }
 
+// CurrentRouteRange mock implementation of CurrentRouteRange from Manager interface
+func (m *MockManager) CurrentRouteRange() []string {
+	return nil
+}
+
 // UpdateRoutes mock implementation of UpdateRoutes from Manager interface
 func (m *MockManager) UpdateRoutes(updateSerial uint64, newRoutes map[route.ID]*route.Route, clientRoutes route.HAMap, useNewDNSRoute bool) error {
 	if m.UpdateRoutesFunc != nil {

client/internal/routemanager/notifier/notifier_android.go

@@ -6,42 +6,47 @@ import (
 	"net/netip"
 	"slices"
 	"sort"
-	"strings"
 	"sync"
 
 	"github.com/netbirdio/netbird/client/internal/listener"
 	"github.com/netbirdio/netbird/route"
 )
 
 type Notifier struct {
+	mu sync.Mutex
+
 	initialRoutes []*route.Route
+	// currentRoutes is the last announced route set. It exists only to
+	// suppress noise: without it every network map sync would trigger the
+	// Java side, even when the routes did not change. The actual TUN route
+	// state is owned by the route manager and pulled from there.
 	currentRoutes []*route.Route
-	fakeIPRoutes  []*route.Route
 
-	listener    listener.NetworkChangeListener
-	listenerMux sync.Mutex
+	listener listener.NetworkChangeListener
 }
 
 func NewNotifier() *Notifier {
 	return &Notifier{}
 }
 
 func (n *Notifier) SetListener(listener listener.NetworkChangeListener) {
-	n.listenerMux.Lock()
-	defer n.listenerMux.Unlock()
+	n.mu.Lock()
+	defer n.mu.Unlock()
 	n.listener = listener
 }
 
 // SetInitialClientRoutes stores the initial route sets for TUN configuration.
 func (n *Notifier) SetInitialClientRoutes(initialRoutes []*route.Route, routesForComparison []*route.Route) {
+	n.mu.Lock()
+	defer n.mu.Unlock()
 	n.initialRoutes = filterStatic(initialRoutes)
 	n.currentRoutes = filterStatic(routesForComparison)
 }
 
-// SetFakeIPRoutes stores the fake IP routes to be included in every TUN rebuild.
-func (n *Notifier) SetFakeIPRoutes(routes []*route.Route) {
-	n.fakeIPRoutes = routes
-	n.notify()
+func (n *Notifier) NotifyRouteChange() {
+	n.mu.Lock()
+	defer n.mu.Unlock()
+	n.notifyLocked()
 }
 
 func (n *Notifier) OnNewRoutes(idMap route.HAMap) {
@@ -55,31 +60,37 @@ func (n *Notifier) OnNewRoutes(idMap route.HAMap) {
 		}
 	}
 
-	if !n.hasRouteDiff(n.currentRoutes, newRoutes) {
+	n.mu.Lock()
+	defer n.mu.Unlock()
+	if !hasRouteDiff(n.currentRoutes, newRoutes) {
 		return
 	}
 
 	n.currentRoutes = newRoutes
-	n.notify()
+	n.notifyLocked()
 }
 
 func (n *Notifier) OnNewPrefixes([]netip.Prefix) {
 	// Not used on Android
 }
 
-func (n *Notifier) notify() {
-	n.listenerMux.Lock()
-	defer n.listenerMux.Unlock()
+func (n *Notifier) notifyLocked() {
 	if n.listener == nil {
 		return
 	}
+	n.listener.OnNetworkChanged("")
+}
 
-	allRoutes := slices.Clone(n.currentRoutes)
-	allRoutes = append(allRoutes, n.fakeIPRoutes...)
+func (n *Notifier) GetInitialRouteRanges() []string {
+	n.mu.Lock()
+	defer n.mu.Unlock()
+	initialStrings := routesToStrings(n.initialRoutes)
+	sort.Strings(initialStrings)
+	return initialStrings
+}
 
-	routeStrings := n.routesToStrings(allRoutes)
-	sort.Strings(routeStrings)
-	n.listener.OnNetworkChanged(strings.Join(routeStrings, ","))
+func (n *Notifier) Close() {
+	// unused
 }
 
 func filterStatic(routes []*route.Route) []*route.Route {
@@ -92,28 +103,18 @@ func filterStatic(routes []*route.Route) []*route.Route {
 	return out
 }
 
-func (n *Notifier) routesToStrings(routes []*route.Route) []string {
+func routesToStrings(routes []*route.Route) []string {
 	nets := make([]string, 0, len(routes))
 	for _, r := range routes {
 		nets = append(nets, r.NetString())
 	}
 	return nets
 }
 
-func (n *Notifier) hasRouteDiff(a []*route.Route, b []*route.Route) bool {
-	as := n.routesToStrings(a)
-	bs := n.routesToStrings(b)
+func hasRouteDiff(a []*route.Route, b []*route.Route) bool {
+	as := routesToStrings(a)
+	bs := routesToStrings(b)
 	sort.Strings(as)
 	sort.Strings(bs)
 	return !slices.Equal(as, bs)
 }
-
-func (n *Notifier) GetInitialRouteRanges() []string {
-	initialStrings := n.routesToStrings(n.initialRoutes)
-	sort.Strings(initialStrings)
-	return initialStrings
-}
-
-func (n *Notifier) Close() {
-	// unused
-}

client/internal/routemanager/notifier/notifier_ios.go

@@ -33,7 +33,7 @@ func (n *Notifier) SetInitialClientRoutes([]*route.Route, []*route.Route) {
 	// iOS doesn't care about initial routes
 }
 
-func (n *Notifier) SetFakeIPRoutes([]*route.Route) {
+func (n *Notifier) NotifyRouteChange() {
 	// Not used on iOS
 }
 

client/internal/routemanager/notifier/notifier_other.go

@@ -23,7 +23,7 @@ func (n *Notifier) SetInitialClientRoutes([]*route.Route, []*route.Route) {
 	// Not used on non-mobile platforms
 }
 
-func (n *Notifier) SetFakeIPRoutes([]*route.Route) {
+func (n *Notifier) NotifyRouteChange() {
 	// Not used on non-mobile platforms
 }