Fix route notificaiton

client/internal/routemanager/manager.go

@@ -8,6 +8,7 @@ import (
 	"net/netip"
 	"net/url"
 	"runtime"
+	"slices"
 	"sync"
 	"time"
 
@@ -142,6 +143,7 @@ func NewManager(config ManagerConfig) *DefaultManager {
 func (m *DefaultManager) setupAndroidRoutes(config ManagerConfig) {
 	cr := m.initialClientRoutes(config.InitialRoutes)
 
+	routesForComparison := slices.Clone(cr)
 	if config.DNSFeatureFlag {
 		m.fakeIPManager = fakeip.NewManager()
 
@@ -156,7 +158,7 @@ func (m *DefaultManager) setupAndroidRoutes(config ManagerConfig) {
 		cr = append(cr, fakeIPRoute)
 	}
 
-	m.notifier.SetInitialClientRoutes(cr, config.DNSFeatureFlag)
+	m.notifier.SetInitialClientRoutes(cr, routesForComparison, config.DNSFeatureFlag)
 }
 
 func (m *DefaultManager) setupRefCounters(useNoop bool) {

client/internal/routemanager/notifier/notifier.go

@@ -3,6 +3,7 @@ package notifier
 import (
 	"net/netip"
 	"runtime"
+	"slices"
 	"sort"
 	"strings"
 	"sync"
@@ -12,8 +13,9 @@ import (
 )
 
 type Notifier struct {
-	initialRouteRanges []string
-	routeRanges        []string
+	initialRoutes       []*route.Route
+	routesForComparison []*route.Route
+	dnsFeatureFlag      bool
 
 	listener    listener.NetworkChangeListener
 	listenerMux sync.Mutex
@@ -29,17 +31,10 @@ func (n *Notifier) SetListener(listener listener.NetworkChangeListener) {
 	n.listener = listener
 }
 
-func (n *Notifier) SetInitialClientRoutes(clientRoutes []*route.Route, dnsFeatureFlag bool) {
-	nets := make([]string, 0)
-	for _, r := range clientRoutes {
-		if r.IsDynamic() && !dnsFeatureFlag {
-			// this kind of dynamic route is not supported on android
-			continue
-		}
-		nets = append(nets, r.Network.String())
-	}
-	sort.Strings(nets)
-	n.initialRouteRanges = nets
+func (n *Notifier) SetInitialClientRoutes(allRoutes []*route.Route, routesForComparison []*route.Route, dnsFeatureFlag bool) {
+	n.dnsFeatureFlag = dnsFeatureFlag
+	n.initialRoutes = allRoutes
+	n.routesForComparison = routesForComparison
 }
 
 func (n *Notifier) OnNewRoutes(idMap route.HAMap) {
@@ -47,22 +42,16 @@ func (n *Notifier) OnNewRoutes(idMap route.HAMap) {
 		return
 	}
 
-	var newNets []string
+	var newRoutes []*route.Route
 	for _, routes := range idMap {
-		for _, r := range routes {
-			if r.IsDynamic() {
-				continue
-			}
-			newNets = append(newNets, r.Network.String())
-		}
+		newRoutes = append(newRoutes, routes...)
 	}
 
-	sort.Strings(newNets)
-	if !n.hasDiff(n.initialRouteRanges, newNets) {
+	if !n.hasRouteDiff(n.routesForComparison, newRoutes) {
 		return
 	}
 
-	n.routeRanges = newNets
+	n.routesForComparison = newRoutes
 	n.notify()
 }
 
@@ -74,11 +63,12 @@ func (n *Notifier) OnNewPrefixes(prefixes []netip.Prefix) {
 	}
 
 	sort.Strings(newNets)
-	if !n.hasDiff(n.routeRanges, newNets) {
+
+	currentNets := n.routesToStrings(n.routesForComparison)
+	if slices.Equal(currentNets, newNets) {
 		return
 	}
 
-	n.routeRanges = newNets
 	n.notify()
 }
 
@@ -89,37 +79,67 @@ func (n *Notifier) notify() {
 		return
 	}
 
+	routeStrings := n.routesToStrings(n.routesForComparison)
+	sort.Strings(routeStrings)
 	go func(l listener.NetworkChangeListener) {
-		l.OnNetworkChanged(strings.Join(addIPv6RangeIfNeeded(n.routeRanges), ","))
+		l.OnNetworkChanged(strings.Join(n.addIPv6RangeIfNeeded(routeStrings, n.routesForComparison), ","))
 	}(n.listener)
 }
 
-func (n *Notifier) hasDiff(a []string, b []string) bool {
-	if len(a) != len(b) {
-		return true
-	}
-	for i, v := range a {
-		if v != b[i] {
-			return true
+// hasRouteDiff compares two route slices for differences
+func (n *Notifier) hasRouteDiff(a []*route.Route, b []*route.Route) bool {
+	aFiltered := n.filterRoutes(a)
+	bFiltered := n.filterRoutes(b)
+
+	slices.SortFunc(aFiltered, func(x, y *route.Route) int {
+		return strings.Compare(x.NetString(), y.NetString())
+	})
+	slices.SortFunc(bFiltered, func(x, y *route.Route) int {
+		return strings.Compare(x.NetString(), y.NetString())
+	})
+
+	return !slices.EqualFunc(aFiltered, bFiltered, func(x, y *route.Route) bool {
+		return x.NetString() == y.NetString()
+	})
+}
+
+// filterRoutes filters routes based on DNS feature flag
+func (n *Notifier) filterRoutes(routes []*route.Route) []*route.Route {
+	filtered := make([]*route.Route, 0, len(routes))
+	for _, r := range routes {
+		if r.IsDynamic() && !n.dnsFeatureFlag {
+			// this kind of dynamic route is not supported on android
+			continue
 		}
+		filtered = append(filtered, r)
 	}
-	return false
+	return filtered
+}
+
+// routesToStrings converts routes to string slice (caller should sort if needed)
+func (n *Notifier) routesToStrings(routes []*route.Route) []string {
+	filtered := n.filterRoutes(routes)
+	nets := make([]string, 0, len(filtered))
+	for _, r := range filtered {
+		nets = append(nets, r.NetString())
+	}
+	return nets
 }
 
 func (n *Notifier) GetInitialRouteRanges() []string {
-	return addIPv6RangeIfNeeded(n.initialRouteRanges)
+	initialStrings := n.routesToStrings(n.initialRoutes)
+	sort.Strings(initialStrings)
+	return n.addIPv6RangeIfNeeded(initialStrings, n.initialRoutes)
 }
 
 // addIPv6RangeIfNeeded returns the input ranges with the default IPv6 range when there is an IPv4 default route.
-func addIPv6RangeIfNeeded(inputRanges []string) []string {
-	ranges := inputRanges
-	for _, r := range inputRanges {
+func (n *Notifier) addIPv6RangeIfNeeded(inputRanges []string, routes []*route.Route) []string {
+	for _, r := range routes {
 		// we are intentionally adding the ipv6 default range in case of ipv4 default range
 		// to ensure that all traffic is managed by the tunnel interface on android
-		if r == "0.0.0.0/0" {
-			ranges = append(ranges, "::/0")
-			break
+		if r.Network.Addr().Is4() && r.Network.Bits() == 0 {
+			return append(slices.Clone(inputRanges), "::/0")
 		}
 	}
-	return ranges
+	return inputRanges
 }