diff --git a/monitor.go b/monitor.go
index 9b903f6..a3b4ef6 100644
--- a/monitor.go
+++ b/monitor.go
@@ -10,14 +10,10 @@ var ErrNoRoute = E.New("no route to internet")
 
 type (
 	NetworkUpdateCallback          = func()
-	DefaultInterfaceUpdateCallback = func(event int)
+	DefaultInterfaceUpdateCallback = func(defaultInterface *control.Interface, flags int)
 )
 
-const (
-	EventInterfaceUpdate  = 1
-	EventAndroidVPNUpdate = 2
-	EventNoRoute          = 4
-)
+const FlagAndroidVPNUpdate = 1 << iota
 
 type NetworkUpdateMonitor interface {
 	Start() error
diff --git a/monitor_android.go b/monitor_android.go
index d058169..2734c85 100644
--- a/monitor_android.go
+++ b/monitor_android.go
@@ -57,16 +57,13 @@ func (m *defaultInterfaceMonitor) checkUpdate() error {
 		return E.Cause(err, "find updated interface: ", link.Attrs().Name)
 	}
 	m.defaultInterface.Store(newInterface)
-	var event int
-	if oldInterface == nil || !oldInterface.Equals(*newInterface) {
-		event |= EventInterfaceUpdate
+	if oldInterface != nil && oldInterface.Equals(*newInterface) && oldVPNEnabled == m.androidVPNEnabled {
+		return nil
 	}
+	var flags int
 	if oldVPNEnabled != m.androidVPNEnabled {
-		event |= EventAndroidVPNUpdate
+		flags = FlagAndroidVPNUpdate
 	}
-	if event != 0 {
-		m.emit(event)
-	}
-
+	m.emit(newInterface, flags)
 	return nil
 }
diff --git a/monitor_darwin.go b/monitor_darwin.go
index 7529820..88ea90c 100644
--- a/monitor_darwin.go
+++ b/monitor_darwin.go
@@ -174,7 +174,7 @@ func (m *defaultInterfaceMonitor) checkUpdate() error {
 	if oldInterface != nil && oldInterface.Equals(*newInterface) {
 		return nil
 	}
-	m.emit(EventInterfaceUpdate)
+	m.emit(newInterface, 0)
 	return nil
 }
 
diff --git a/monitor_linux_default.go b/monitor_linux_default.go
index 0cb6b19..e9cce1d 100644
--- a/monitor_linux_default.go
+++ b/monitor_linux_default.go
@@ -34,7 +34,7 @@ func (m *defaultInterfaceMonitor) checkUpdate() error {
 		if oldInterface != nil && oldInterface.Equals(*newInterface) {
 			return nil
 		}
-		m.emit(EventInterfaceUpdate)
+		m.emit(newInterface, 0)
 		return nil
 	}
 	return ErrNoRoute
diff --git a/monitor_shared.go b/monitor_shared.go
index d742906..a5ee4e3 100644
--- a/monitor_shared.go
+++ b/monitor_shared.go
@@ -84,7 +84,7 @@ func (m *defaultInterfaceMonitor) postCheckUpdate() {
 		if !m.noRoute {
 			m.noRoute = true
 			m.defaultInterface.Store(nil)
-			m.emit(EventNoRoute)
+			m.emit(nil, 0)
 		}
 	} else if err != nil {
 		m.logger.Error("check interface: ", err)
@@ -124,11 +124,11 @@ func (m *defaultInterfaceMonitor) UnregisterCallback(element *list.Element[Defau
 	m.callbacks.Remove(element)
 }
 
-func (m *defaultInterfaceMonitor) emit(event int) {
+func (m *defaultInterfaceMonitor) emit(defaultInterface *control.Interface, flags int) {
 	m.access.Lock()
 	callbacks := m.callbacks.Array()
 	m.access.Unlock()
 	for _, callback := range callbacks {
-		callback(event)
+		callback(defaultInterface, flags)
 	}
 }
diff --git a/monitor_windows.go b/monitor_windows.go
index 38de4ab..d58e701 100644
--- a/monitor_windows.go
+++ b/monitor_windows.go
@@ -111,6 +111,6 @@ func (m *defaultInterfaceMonitor) checkUpdate() error {
 	if oldInterface != nil && !oldInterface.Equals(*newInterface) {
 		return nil
 	}
-	m.emit(EventInterfaceUpdate)
+	m.emit(newInterface, 0)
 	return nil
 }
diff --git a/tun_linux.go b/tun_linux.go
index a799b8d..15b6a29 100644
--- a/tun_linux.go
+++ b/tun_linux.go
@@ -16,6 +16,7 @@ import (
 	"github.com/sagernet/sing/common"
 	"github.com/sagernet/sing/common/buf"
 	"github.com/sagernet/sing/common/bufio"
+	"github.com/sagernet/sing/common/control"
 	E "github.com/sagernet/sing/common/exceptions"
 	N "github.com/sagernet/sing/common/network"
 	"github.com/sagernet/sing/common/rw"
@@ -881,8 +882,8 @@ func (t *NativeTun) resetRules() error {
 	return t.setRules()
 }
 
-func (t *NativeTun) routeUpdate(event int) {
-	if event&EventAndroidVPNUpdate == 0 {
+func (t *NativeTun) routeUpdate(_ *control.Interface, flags int) {
+	if flags&FlagAndroidVPNUpdate == 0 {
 		return
 	}
 	err := t.resetRules()