feat(android): Add support for per-app VPN configurable through MDM (#3657)

Refs #3613

kotlin/android/app/src/main/java/dev/firezone/android/core/data/RepositoryImpl.kt

@@ -3,7 +3,6 @@ package dev.firezone.android.core.data
 
 import android.content.Context
 import android.content.SharedPreferences
-import android.os.Bundle
 import dev.firezone.android.BuildConfig
 import dev.firezone.android.core.data.model.Config
 import kotlinx.coroutines.CoroutineDispatcher
@@ -19,7 +18,6 @@ internal class RepositoryImpl
         private val context: Context,
         private val coroutineDispatcher: CoroutineDispatcher,
         private val sharedPreferences: SharedPreferences,
-        private val appRestrictions: Bundle,
     ) : Repository {
         override fun getConfigSync(): Config {
             return Config(
@@ -69,15 +67,10 @@ internal class RepositoryImpl
 
         override fun getToken(): Flow<String?> =
             flow {
-                emit(
-                    appRestrictions.getString(TOKEN_KEY, null)
-                        ?: sharedPreferences.getString(TOKEN_KEY, null),
-                )
+                emit(sharedPreferences.getString(TOKEN_KEY, null))
             }.flowOn(coroutineDispatcher)
 
-        override fun getTokenSync(): String? =
-            appRestrictions.getString(TOKEN_KEY, null)
-                ?: sharedPreferences.getString(TOKEN_KEY, null)
+        override fun getTokenSync(): String? = sharedPreferences.getString(TOKEN_KEY, null)
 
         override fun getStateSync(): String? = sharedPreferences.getString(STATE_KEY, null)
 

kotlin/android/app/src/main/java/dev/firezone/android/core/di/DataModule.kt

@@ -3,6 +3,7 @@ package dev.firezone.android.core.di
 
 import android.content.Context
 import android.content.SharedPreferences
+import android.os.Bundle
 import androidx.core.content.getSystemService
 import dagger.Module
 import dagger.Provides
@@ -16,6 +17,11 @@ import kotlinx.coroutines.CoroutineDispatcher
 @Module
 @InstallIn(SingletonComponent::class)
 class DataModule {
+    @Provides
+    internal fun provideApplicationRestrictions(
+        @ApplicationContext context: Context,
+    ): Bundle = (context.getSystemService(Context.RESTRICTIONS_SERVICE) as android.content.RestrictionsManager).applicationRestrictions
+
     @Provides
     internal fun provideRepository(
         @ApplicationContext context: Context,
@@ -26,9 +32,5 @@ class DataModule {
             context,
             coroutineDispatcher,
             sharedPreferences,
-            (
-                context.getSystemService(Context.RESTRICTIONS_SERVICE)
-                    as android.content.RestrictionsManager
-            ).applicationRestrictions,
         )
 }

kotlin/android/app/src/main/java/dev/firezone/android/features/splash/ui/SplashViewModel.kt

@@ -2,6 +2,7 @@
 package dev.firezone.android.features.splash.ui
 
 import android.content.Context
+import android.os.Bundle
 import androidx.lifecycle.LiveData
 import androidx.lifecycle.MutableLiveData
 import androidx.lifecycle.ViewModel
@@ -10,7 +11,6 @@ import dagger.hilt.android.lifecycle.HiltViewModel
 import dev.firezone.android.core.data.Repository
 import dev.firezone.android.tunnel.TunnelService
 import kotlinx.coroutines.delay
-import kotlinx.coroutines.flow.collect
 import kotlinx.coroutines.launch
 import javax.inject.Inject
 
@@ -21,6 +21,7 @@ internal class SplashViewModel
     @Inject
     constructor(
         private val repo: Repository,
+        private val applicationRestrictions: Bundle,
     ) : ViewModel() {
         private val actionMutableLiveData = MutableLiveData<ViewAction>()
         val actionLiveData: LiveData<ViewAction> = actionMutableLiveData
@@ -32,15 +33,14 @@ internal class SplashViewModel
                 if (!hasVpnPermissions(context)) {
                     actionMutableLiveData.postValue(ViewAction.NavigateToVpnPermission)
                 } else {
-                    repo.getToken().collect {
-                        if (it.isNullOrBlank()) {
-                            actionMutableLiveData.postValue(ViewAction.NavigateToSignIn)
-                        } else {
-                            // token will be re-read by the TunnelService
-                            if (!TunnelService.isRunning(context)) TunnelService.start(context)
+                    val token = applicationRestrictions.getString("token") ?: repo.getTokenSync()
+                    if (token.isNullOrBlank()) {
+                        actionMutableLiveData.postValue(ViewAction.NavigateToSignIn)
+                    } else {
+                        // token will be re-read by the TunnelService
+                        if (!TunnelService.isRunning(context)) TunnelService.start(context)
 
-                            actionMutableLiveData.postValue(ViewAction.NavigateToSession)
-                        }
+                        actionMutableLiveData.postValue(ViewAction.NavigateToSession)
                     }
                 }
             }

kotlin/android/app/src/main/java/dev/firezone/android/tunnel/TunnelService.kt

@@ -11,6 +11,7 @@ import android.content.Intent
 import android.net.VpnService
 import android.os.Binder
 import android.os.Build
+import android.os.Bundle
 import android.os.IBinder
 import android.util.Log
 import androidx.core.app.NotificationCompat
@@ -38,6 +39,9 @@ class TunnelService : VpnService() {
     @Inject
     internal lateinit var repo: Repository
 
+    @Inject
+    internal lateinit var appRestrictions: Bundle
+
     @Inject
     internal lateinit var moshi: Moshi
 
@@ -168,7 +172,7 @@ class TunnelService : VpnService() {
                 Log.d(TAG, "onDisconnect: $error")
                 Firebase.crashlytics.log("onDisconnect: $error")
 
-                // This is a no-op if the token is being read from MDM
+                // Clear any user tokens and actorNames
                 repo.clearToken()
                 repo.clearActorName()
 
@@ -214,7 +218,7 @@ class TunnelService : VpnService() {
     }
 
     private fun connect() {
-        val token = repo.getTokenSync()
+        val token = appRestrictions.getString("token") ?: repo.getTokenSync()
         val config = repo.getConfigSync()
 
         if (!token.isNullOrBlank()) {
@@ -321,6 +325,20 @@ class TunnelService : VpnService() {
             Firebase.crashlytics.log("IPv6 Address: $tunnelIpv6Address")
             addAddress(tunnelIpv6Address!!, 128)
 
+            appRestrictions.getString("allowedApplications")?.let {
+                Firebase.crashlytics.log("Allowed applications: $it")
+                it.split(",").forEach { p ->
+                    addAllowedApplication(p.trim())
+                }
+            }
+
+            appRestrictions.getString("disallowedApplications")?.let {
+                Firebase.crashlytics.log("Disallowed applications: $it")
+                it.split(",").forEach { p ->
+                    addDisallowedApplication(p.trim())
+                }
+            }
+
             setSession(SESSION_NAME)
             setMtu(MTU)
         }.establish()!!.let {

kotlin/android/app/src/main/res/values/strings.xml

@@ -39,5 +39,9 @@
 
 	<!-- Managed Configuration -->
 	<string name="config_token_title">Token</string>
-	<string name="config_token_description">The token used for authentication. Set this to a service account token to achieve headless operation.</string>
+	<string name="config_token_description">The token used for authentication. Set this to a service account token to enable headless operation.</string>
+	<string name="config_allowed_applications_title">Allowed Applications</string>
+	<string name="config_allowed_applications_description">A comma-separated list of application package IDs that are allowed to use the Firezone tunnel. If this list is empty, all applications are allowed.</string>
+	<string name="config_disallowed_applications_title">Disallowed Applications</string>
+	<string name="config_disallowed_applications_description">A comma-separated list of application package IDs that are disallowed to use the Firezone tunnel and will be routed outside of it. If this list is empty, no applications are disallowed.</string>
 </resources>

kotlin/android/app/src/main/res/xml/app_restrictions.xml

@@ -7,4 +7,15 @@
         android:restrictionType="string"
         android:title="@string/config_token_title" />
 
+    <restriction
+        android:description="@string/config_allowed_applications_description"
+        android:key="allowedApplications"
+        android:restrictionType="string"
+        android:title="@string/config_allowed_applications_title" />
+
+    <restriction
+        android:description="@string/config_disallowed_applications_description"
+        android:key="disallowedApplications"
+        android:restrictionType="string"
+        android:title="@string/config_disallowed_applications_title" />
 </restrictions>