android: replace broadcast intent with service intent

We were previously calling startService(intent), which is a direct call consumed by IPNService, but restartVPN was not working as intended because the broadcast receiver was never triggered.
Rather than use a broadcast receiver, directly start the service in restartVPN as we do in stopVPN. Also, batch changes to excluded apps so that we don't restart the VPN each time the user toggles an app.

Fixes tailscale/corp#28668

Signed-off-by: kari-ts <[email protected]>

Author: kari-ts

android/src/main/java/com/tailscale/ipn/App.kt

@@ -7,7 +7,6 @@ import android.app.Application
 import android.app.Notification
 import android.app.NotificationChannel
 import android.app.PendingIntent
-import android.content.BroadcastReceiver
 import android.content.Context
 import android.content.Intent
 import android.content.IntentFilter
@@ -37,11 +36,6 @@ import com.tailscale.ipn.ui.viewModel.VpnViewModel
 import com.tailscale.ipn.ui.viewModel.VpnViewModelFactory
 import com.tailscale.ipn.util.FeatureFlags
 import com.tailscale.ipn.util.TSLog
-import java.io.File
-import java.io.IOException
-import java.net.NetworkInterface
-import java.security.GeneralSecurityException
-import java.util.Locale
 import kotlinx.coroutines.CoroutineScope
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.SupervisorJob
@@ -53,6 +47,11 @@ import kotlinx.coroutines.launch
 import kotlinx.serialization.encodeToString
 import kotlinx.serialization.json.Json
 import libtailscale.Libtailscale
+import java.io.File
+import java.io.IOException
+import java.net.NetworkInterface
+import java.security.GeneralSecurityException
+import java.util.Locale
 
 class App : UninitializedApp(), libtailscale.AppContext, ViewModelStoreOwner {
   val applicationScope = CoroutineScope(SupervisorJob() + Dispatchers.Default)
@@ -470,25 +469,15 @@ open class UninitializedApp : Application() {
   }
 
   fun restartVPN() {
-    // Register a receiver to listen for the completion of stopVPN
-    val stopReceiver =
-        object : BroadcastReceiver() {
-          override fun onReceive(context: Context?, intent: Intent?) {
-            // Ensure stop intent is complete
-            if (intent?.action == IPNService.ACTION_STOP_VPN) {
-              // Unregister receiver after receiving the broadcast
-              context?.unregisterReceiver(this)
-              // Now start the VPN
-              startVPN()
-            }
-          }
-        }
-
-    // Register the receiver before stopping VPN
-    val intentFilter = IntentFilter(IPNService.ACTION_STOP_VPN)
-    this.registerReceiver(stopReceiver, intentFilter, Context.RECEIVER_NOT_EXPORTED)
-
-    stopVPN()
+    val intent =
+        Intent(this, IPNService::class.java).apply { action = IPNService.ACTION_RESTART_VPN }
+    try {
+      startService(intent)
+    } catch (illegalStateException: IllegalStateException) {
+      TSLog.e(TAG, "restartVPN hit IllegalStateException in startService(): $illegalStateException")
+    } catch (e: Exception) {
+      TSLog.e(TAG, "restartVPN hit exception in startService(): $e")
+    }
   }
 
   fun createNotificationChannel(id: String, name: String, description: String, importance: Int) {
@@ -569,33 +558,13 @@ open class UninitializedApp : Application() {
     return builder.build()
   }
 
-  fun addUserDisallowedPackageName(packageName: String) {
-    if (packageName.isEmpty()) {
-      TSLog.e(TAG, "addUserDisallowedPackageName called with empty packageName")
-      return
-    }
-
-    getUnencryptedPrefs()
-        .edit()
-        .putStringSet(
-            DISALLOWED_APPS_KEY, disallowedPackageNames().toMutableSet().union(setOf(packageName)))
-        .apply()
-
-    this.restartVPN()
-  }
-
-  fun removeUserDisallowedPackageName(packageName: String) {
-    if (packageName.isEmpty()) {
-      TSLog.e(TAG, "removeUserDisallowedPackageName called with empty packageName")
+  fun updateUserDisallowedPackageNames(packageNames: List<String>) {
+    if (packageNames.any { it.isEmpty() }) {
+      TSLog.e(TAG, "updateUserDisallowedPackageNames called with empty packageName(s)")
       return
     }
 
-    getUnencryptedPrefs()
-        .edit()
-        .putStringSet(
-            DISALLOWED_APPS_KEY,
-            disallowedPackageNames().toMutableSet().subtract(setOf(packageName)))
-        .apply()
+    getUnencryptedPrefs().edit().putStringSet(DISALLOWED_APPS_KEY, packageNames.toSet()).apply()
 
     this.restartVPN()
   }

android/src/main/java/com/tailscale/ipn/IPNService.kt

@@ -12,12 +12,12 @@ import com.tailscale.ipn.mdm.MDMSettings
 import com.tailscale.ipn.ui.model.Ipn
 import com.tailscale.ipn.ui.notifier.Notifier
 import com.tailscale.ipn.util.TSLog
-import java.util.UUID
 import kotlinx.coroutines.CoroutineScope
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.flow.first
 import kotlinx.coroutines.launch
 import libtailscale.Libtailscale
+import java.util.UUID
 
 open class IPNService : VpnService(), libtailscale.IPNService {
   private val TAG = "IPNService"
@@ -46,6 +46,13 @@ open class IPNService : VpnService(), libtailscale.IPNService {
           close()
           START_NOT_STICKY
         }
+        ACTION_RESTART_VPN -> {
+          app.setWantRunning(false){
+            close()
+            app.startVPN()
+          }
+          START_NOT_STICKY
+        }
         ACTION_START_VPN -> {
           scope.launch { showForegroundNotification() }
           app.setWantRunning(true)
@@ -82,7 +89,6 @@ open class IPNService : VpnService(), libtailscale.IPNService {
       }
 
   override fun close() {
-    app.setWantRunning(false) {}
     Notifier.setState(Ipn.State.Stopping)
     disconnectVPN()
     Libtailscale.serviceDisconnect(this)
@@ -180,5 +186,6 @@ open class IPNService : VpnService(), libtailscale.IPNService {
   companion object {
     const val ACTION_START_VPN = "com.tailscale.ipn.START_VPN"
     const val ACTION_STOP_VPN = "com.tailscale.ipn.STOP_VPN"
+    const val ACTION_RESTART_VPN = "com.tailscale.ipn.RESTART_VPN"
   }
 }

android/src/main/java/com/tailscale/ipn/ui/viewModel/SplitTunnelAppPickerViewModel.kt

@@ -4,14 +4,18 @@
 package com.tailscale.ipn.ui.viewModel
 
 import androidx.lifecycle.ViewModel
+import androidx.lifecycle.viewModelScope
 import com.tailscale.ipn.App
 import com.tailscale.ipn.mdm.MDMSettings
 import com.tailscale.ipn.mdm.SettingState
 import com.tailscale.ipn.ui.util.InstalledApp
 import com.tailscale.ipn.ui.util.InstalledAppsManager
 import com.tailscale.ipn.ui.util.set
+import kotlinx.coroutines.Job
+import kotlinx.coroutines.delay
 import kotlinx.coroutines.flow.MutableStateFlow
 import kotlinx.coroutines.flow.StateFlow
+import kotlinx.coroutines.launch
 
 class SplitTunnelAppPickerViewModel : ViewModel() {
   val installedAppsManager = InstalledAppsManager(packageManager = App.get().packageManager)
@@ -20,6 +24,8 @@ class SplitTunnelAppPickerViewModel : ViewModel() {
   val mdmExcludedPackages: StateFlow<SettingState<String?>> = MDMSettings.excludedPackages.flow
   val mdmIncludedPackages: StateFlow<SettingState<String?>> = MDMSettings.includedPackages.flow
 
+  private var saveJob: Job? = null
+
   init {
     installedApps.set(installedAppsManager.fetchInstalledApps())
     excludedPackageNames.set(
@@ -30,15 +36,22 @@ class SplitTunnelAppPickerViewModel : ViewModel() {
   }
 
   fun exclude(packageName: String) {
-    if (excludedPackageNames.value.contains(packageName)) {
-      return
-    }
+    if (excludedPackageNames.value.contains(packageName)) return
     excludedPackageNames.set(excludedPackageNames.value + packageName)
-    App.get().addUserDisallowedPackageName(packageName)
+    debounceSave()
   }
 
   fun unexclude(packageName: String) {
     excludedPackageNames.set(excludedPackageNames.value - packageName)
-    App.get().removeUserDisallowedPackageName(packageName)
+    debounceSave()
+  }
+
+  private fun debounceSave() {
+    saveJob?.cancel()
+    saveJob =
+        viewModelScope.launch {
+          delay(500) // Wait to batch multiple rapid updates
+          App.get().updateUserDisallowedPackageNames(excludedPackageNames.value)
+        }
   }
 }