mobile: local authentication (#696)

Co-authored-by: Evgeny Poberezkin <2769109+epoberezkin@users.noreply.github.com>

apps/android/app/src/main/java/chat/simplex/app/MainActivity.kt

@@ -5,18 +5,17 @@ import android.content.*
 import android.net.Uri
 import android.os.Bundle
 import android.util.Log
-import androidx.activity.ComponentActivity
 import androidx.activity.compose.setContent
 import androidx.activity.viewModels
 import androidx.compose.foundation.background
-import androidx.compose.foundation.isSystemInDarkTheme
 import androidx.compose.foundation.layout.*
 import androidx.compose.material.MaterialTheme
 import androidx.compose.material.Surface
-import androidx.compose.runtime.Composable
+import androidx.compose.runtime.*
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.unit.dp
-import androidx.lifecycle.AndroidViewModel
+import androidx.fragment.app.FragmentActivity
+import androidx.lifecycle.*
 import androidx.work.*
 import chat.simplex.app.model.ChatModel
 import chat.simplex.app.model.NtfManager
@@ -31,18 +30,21 @@ import chat.simplex.app.views.helpers.*
 import chat.simplex.app.views.newchat.connectViaUri
 import chat.simplex.app.views.newchat.withUriAction
 import chat.simplex.app.views.onboarding.*
+import kotlinx.coroutines.delay
 import java.util.concurrent.TimeUnit
 
-//import kotlinx.serialization.decodeFromString
-
-class MainActivity: ComponentActivity() {
+class MainActivity: FragmentActivity(), LifecycleEventObserver {
   private val vm by viewModels<SimplexViewModel>()
   private val chatController by lazy { (application as SimplexApp).chatController }
+  private val userAuthorized = mutableStateOf<Boolean?>(null)
+  private val lastLA = mutableStateOf<Long?>(null)
 
   override fun onCreate(savedInstanceState: Bundle?) {
     super.onCreate(savedInstanceState)
+    ProcessLifecycleOwner.get().lifecycle.addObserver(this)
 //    testJson()
-    processNotificationIntent(intent, vm.chatModel)
+    val m = vm.chatModel
+    processNotificationIntent(intent, m)
     setContent {
       SimpleXTheme {
         Surface(
@@ -50,7 +52,7 @@ class MainActivity: ComponentActivity() {
             .background(MaterialTheme.colors.background)
             .fillMaxSize()
         ) {
-          MainPage(vm.chatModel)
+          MainPage(m, userAuthorized, ::setPerformLA, showLANotice = { m.controller.showLANotice(this) })
         }
       }
     }
@@ -62,6 +64,47 @@ class MainActivity: ComponentActivity() {
     processIntent(intent, vm.chatModel)
   }
 
+  override fun onStateChanged(source: LifecycleOwner, event: Lifecycle.Event) {
+    withApi {
+      when (event) {
+        Lifecycle.Event.ON_START -> {
+          // perform local authentication if needed
+          val m = vm.chatModel
+          val lastLAVal = lastLA.value
+          if (
+            m.controller.getPerformLA()
+            && (lastLAVal == null || (System.nanoTime() - lastLAVal >= 30 * 1e+9))
+          ) {
+            userAuthorized.value = false
+            authenticate(
+              generalGetString(R.string.auth_access_chats),
+              generalGetString(R.string.auth_log_in_using_credential),
+              this@MainActivity,
+              completed = { laResult ->
+                when (laResult) {
+                  LAResult.Success -> {
+                    userAuthorized.value = true
+                    lastLA.value = System.nanoTime()
+                  }
+                  is LAResult.Error -> laErrorToast(applicationContext, laResult.errString)
+                  LAResult.Failed -> laFailedToast(applicationContext)
+                  LAResult.Unavailable -> {
+                    userAuthorized.value = true
+                    m.performLA.value = false
+                    m.controller.setPerformLA(false)
+                    laUnavailableTurningOffAlert()
+                  }
+                }
+              }
+            )
+          } else {
+            userAuthorized.value = true
+          }
+        }
+      }
+    }
+  }
+
   private fun schedulePeriodicServiceRestartWorker() {
     val workerVersion = chatController.getAutoRestartWorkerVersion()
     val workPolicy = if (workerVersion == SimplexService.SERVICE_START_WORKER_VERSION) {
@@ -79,6 +122,73 @@ class MainActivity: ComponentActivity() {
     Log.d(TAG, "ServiceStartWorker: Scheduling period work every ${SimplexService.SERVICE_START_WORKER_INTERVAL_MINUTES} minutes")
     WorkManager.getInstance(this)?.enqueueUniquePeriodicWork(SimplexService.SERVICE_START_WORKER_WORK_NAME_PERIODIC, workPolicy, work)
   }
+
+  private fun setPerformLA(on: Boolean) {
+    val m = vm.chatModel
+    if (on) {
+      m.controller.setLANoticeShown(true)
+      authenticate(
+        generalGetString(R.string.auth_enable),
+        generalGetString(R.string.auth_confirm_credential),
+        this@MainActivity,
+        completed = { laResult ->
+          when (laResult) {
+            LAResult.Success -> {
+              m.performLA.value = true
+              m.controller.setPerformLA(true)
+              userAuthorized.value = true
+              lastLA.value = System.nanoTime()
+              laTurnedOnAlert()
+            }
+            is LAResult.Error -> {
+              m.performLA.value = false
+              m.controller.setPerformLA(false)
+              laErrorToast(applicationContext, laResult.errString)
+            }
+            LAResult.Failed -> {
+              m.performLA.value = false
+              m.controller.setPerformLA(false)
+              laFailedToast(applicationContext)
+            }
+            LAResult.Unavailable -> {
+              m.performLA.value = false
+              m.controller.setPerformLA(false)
+              laUnavailableInstructionAlert()
+            }
+          }
+        }
+      )
+    } else {
+      authenticate(
+        generalGetString(R.string.auth_disable),
+        generalGetString(R.string.auth_confirm_credential),
+        this@MainActivity,
+        completed = { laResult ->
+          when (laResult) {
+            LAResult.Success -> {
+              m.performLA.value = false
+              m.controller.setPerformLA(false)
+            }
+            is LAResult.Error -> {
+              m.performLA.value = true
+              m.controller.setPerformLA(true)
+              laErrorToast(applicationContext, laResult.errString)
+            }
+            LAResult.Failed -> {
+              m.performLA.value = true
+              m.controller.setPerformLA(true)
+              laFailedToast(applicationContext)
+            }
+            LAResult.Unavailable -> {
+              m.performLA.value = false
+              m.controller.setPerformLA(false)
+              laUnavailableTurningOffAlert()
+            }
+          }
+        }
+      )
+    }
+  }
 }
 
 class SimplexViewModel(application: Application): AndroidViewModel(application) {
@@ -87,22 +197,54 @@ class SimplexViewModel(application: Application): AndroidViewModel(application)
 }
 
 @Composable
-fun MainPage(chatModel: ChatModel) {
+fun MainPage(
+  chatModel: ChatModel,
+  userAuthorized: MutableState<Boolean?>,
+  setPerformLA: (Boolean) -> Unit,
+  showLANotice: () -> Unit
+) {
+  // this with LaunchedEffect(userAuthorized.value) fixes bottom sheet visibly collapsing after authentication
+  var chatsAccessAuthorized by remember { mutableStateOf<Boolean>(false) }
+  LaunchedEffect(userAuthorized.value) {
+    delay(500L)
+    chatsAccessAuthorized = userAuthorized.value == true
+  }
+  var showAdvertiseLAAlert by remember { mutableStateOf(false) }
+  LaunchedEffect(showAdvertiseLAAlert) {
+    if (
+      !chatModel.controller.getLANoticeShown()
+      && showAdvertiseLAAlert
+      && chatModel.onboardingStage.value == OnboardingStage.OnboardingComplete
+      && chatModel.chats.isNotEmpty()
+      && chatModel.activeCallInvitation.value == null
+    ) {
+      showLANotice()
+    }
+  }
+  LaunchedEffect(chatModel.showAdvertiseLAUnavailableAlert.value) {
+    if (chatModel.showAdvertiseLAUnavailableAlert.value) {
+      laUnavailableInstructionAlert()
+    }
+  }
   Box {
     val onboarding = chatModel.onboardingStage.value
     val userCreated = chatModel.userCreated.value
     when {
       onboarding == null || userCreated == null -> SplashView()
+      !chatsAccessAuthorized -> SplashView()
       onboarding == OnboardingStage.OnboardingComplete && userCreated -> {
         Box {
           if (chatModel.showCallView.value) ActiveCallView(chatModel)
-          else if (chatModel.chatId.value == null) ChatListView(chatModel)
-          else ChatView(chatModel)
-
+          else {
+            showAdvertiseLAAlert = true
+            if (chatModel.chatId.value == null) ChatListView(chatModel, setPerformLA = { setPerformLA(it) })
+            else ChatView(chatModel)
+          }
           val invitation = chatModel.activeCallInvitation.value
           if (invitation != null) IncomingCallAlertView(invitation, chatModel)
         }
-      } onboarding == OnboardingStage.Step1_SimpleXInfo ->
+      }
+      onboarding == OnboardingStage.Step1_SimpleXInfo ->
         Box(Modifier.padding(horizontal = 20.dp)) {
           SimpleXInfo(chatModel, onboarding = true)
         }
@@ -180,7 +322,6 @@ fun connectIfOpenedViaUri(uri: Uri, chatModel: ChatModel) {
     }
   }
 }
-
 //fun testJson() {
 //  val str: String = """
 //  """.trimIndent()

apps/android/app/src/main/java/chat/simplex/app/model/ChatModel.kt

@@ -37,7 +37,11 @@ class ChatModel(val controller: ChatController) {
 
   // set when app is opened via contact or invitation URI
   val appOpenUrl = mutableStateOf<Uri?>(null)
+
+  // preferences
   val runServiceInBackground = mutableStateOf(true)
+  val performLA = mutableStateOf(false)
+  val showAdvertiseLAUnavailableAlert = mutableStateOf(false)
 
   // current WebRTC call
   val callManager = CallManager(this)

apps/android/app/src/main/java/chat/simplex/app/model/SimpleXAPI.kt

@@ -18,6 +18,7 @@ import androidx.compose.ui.Modifier
 import androidx.compose.ui.res.stringResource
 import androidx.compose.ui.text.font.FontWeight
 import androidx.compose.ui.unit.dp
+import androidx.fragment.app.FragmentActivity
 import chat.simplex.app.*
 import chat.simplex.app.R
 import chat.simplex.app.views.call.*
@@ -51,6 +52,7 @@ open class ChatController(private val ctrl: ChatCtrl, val ntfManager: NtfManager
 
   init {
     chatModel.runServiceInBackground.value = getRunServiceInBackground()
+    chatModel.performLA.value = getPerformLA()
   }
 
   suspend fun startChat(user: User) {
@@ -691,6 +693,49 @@ open class ChatController(private val ctrl: ChatCtrl, val ntfManager: NtfManager
     )
   }
 
+  fun showLANotice(activity: FragmentActivity) {
+    Log.d(TAG, "showLANotice")
+    if (!getLANoticeShown()) {
+      setLANoticeShown(true)
+      AlertManager.shared.showAlertDialog(
+        title = generalGetString(R.string.la_notice_title),
+        text = generalGetString(R.string.la_notice_text),
+        confirmText = generalGetString(R.string.la_notice_turn_on),
+        onConfirm = {
+          authenticate(
+            generalGetString(R.string.auth_enable),
+            generalGetString(R.string.auth_confirm_credential),
+            activity,
+            completed = { laResult ->
+              when (laResult) {
+                LAResult.Success -> {
+                  chatModel.performLA.value = true
+                  setPerformLA(true)
+                  laTurnedOnAlert()
+                }
+                is LAResult.Error -> {
+                  chatModel.performLA.value = false
+                  setPerformLA(false)
+                  laErrorToast(appContext, laResult.errString)
+                }
+                LAResult.Failed -> {
+                  chatModel.performLA.value = false
+                  setPerformLA(false)
+                  laFailedToast(appContext)
+                }
+                LAResult.Unavailable -> {
+                  chatModel.performLA.value = false
+                  setPerformLA(false)
+                  chatModel.showAdvertiseLAUnavailableAlert.value = true
+                }
+              }
+            }
+          )
+        }
+      )
+    }
+  }
+
   fun getAutoRestartWorkerVersion(): Int = sharedPreferences.getInt(SHARED_PREFS_AUTO_RESTART_WORKER_VERSION, 0)
 
   fun setAutoRestartWorkerVersion(version: Int) =
@@ -738,12 +783,28 @@ open class ChatController(private val ctrl: ChatCtrl, val ntfManager: NtfManager
     }
   }
 
+  fun getPerformLA(): Boolean = sharedPreferences.getBoolean(SHARED_PREFS_PERFORM_LA, false)
+
+  fun setPerformLA(performLA: Boolean) =
+    sharedPreferences.edit()
+      .putBoolean(SHARED_PREFS_PERFORM_LA, performLA)
+      .apply()
+
+  fun getLANoticeShown(): Boolean = sharedPreferences.getBoolean(SHARED_PREFS_LA_NOTICE_SHOWN, false)
+
+  fun setLANoticeShown(shown: Boolean) =
+    sharedPreferences.edit()
+      .putBoolean(SHARED_PREFS_LA_NOTICE_SHOWN, shown)
+      .apply()
+
   companion object {
     private const val SHARED_PREFS_ID = "chat.simplex.app.SIMPLEX_APP_PREFS"
     private const val SHARED_PREFS_AUTO_RESTART_WORKER_VERSION = "AutoRestartWorkerVersion"
     private const val SHARED_PREFS_RUN_SERVICE_IN_BACKGROUND = "RunServiceInBackground"
     private const val SHARED_PREFS_SERVICE_NOTICE_SHOWN = "BackgroundServiceNoticeShown"
     private const val SHARED_PREFS_SERVICE_BATTERY_NOTICE_SHOWN = "BackgroundServiceBatteryNoticeShown"
+    private const val SHARED_PREFS_PERFORM_LA = "PerformLA"
+    private const val SHARED_PREFS_LA_NOTICE_SHOWN = "LANoticeShown"
   }
 }
 

apps/android/app/src/main/java/chat/simplex/app/views/chatlist/ChatListNavLinkView.kt

@@ -22,7 +22,6 @@ import chat.simplex.app.views.chat.deleteContactDialog
 import chat.simplex.app.views.chat.item.ItemAction
 import chat.simplex.app.views.helpers.*
 import kotlinx.coroutines.delay
-import kotlinx.coroutines.launch
 import kotlinx.datetime.Clock
 
 @Composable
@@ -31,10 +30,8 @@ fun ChatListNavLinkView(chat: Chat, chatModel: ChatModel) {
   var showMarkRead by remember { mutableStateOf(false) }
   LaunchedEffect(chat.id, chat.chatStats.unreadCount > 0) {
     showMenu.value = false
-    launch {
-      delay(500L)
-      showMarkRead = chat.chatStats.unreadCount > 0
-    }
+    delay(500L)
+    showMarkRead = chat.chatStats.unreadCount > 0
   }
   when (chat.chatInfo) {
     is ChatInfo.Direct ->

apps/android/app/src/main/java/chat/simplex/app/views/chatlist/ChatListView.kt

@@ -64,7 +64,7 @@ fun scaffoldController(): ScaffoldController {
 }
 
 @Composable
-fun ChatListView(chatModel: ChatModel) {
+fun ChatListView(chatModel: ChatModel, setPerformLA: (Boolean) -> Unit) {
   val scaffoldCtrl = scaffoldController()
   if (chatModel.clearOverlays.value) {
     scaffoldCtrl.collapse()
@@ -73,7 +73,7 @@ fun ChatListView(chatModel: ChatModel) {
   }
   BottomSheetScaffold(
     scaffoldState = scaffoldCtrl.state,
-    drawerContent = { SettingsView(chatModel) },
+    drawerContent = { SettingsView(chatModel, setPerformLA) },
     sheetPeekHeight = 0.dp,
     sheetContent = { NewChatSheet(chatModel, scaffoldCtrl) },
     sheetShape = RoundedCornerShape(topStart = 18.dp, topEnd = 18.dp),
@@ -104,43 +104,6 @@ fun ChatListView(chatModel: ChatModel) {
   }
 }
 
-@Composable
-fun Help(scaffoldCtrl: ScaffoldController, displayName: String?) {
-  Column(
-    Modifier
-      .verticalScroll(rememberScrollState())
-      .fillMaxWidth()
-      .padding(16.dp)
-  ) {
-    val welcomeMsg = if (displayName != null) {
-      String.format(stringResource(R.string.personal_welcome), displayName)
-    } else stringResource(R.string.welcome)
-    Text(
-      text = welcomeMsg,
-      Modifier.padding(bottom = 24.dp),
-      style = MaterialTheme.typography.h1,
-      color = MaterialTheme.colors.onBackground
-    )
-    ChatHelpView { scaffoldCtrl.toggleSheet() }
-    Row(
-      Modifier.padding(top = 30.dp),
-      verticalAlignment = Alignment.CenterVertically,
-      horizontalArrangement = Arrangement.spacedBy(8.dp)
-    ) {
-      Text(
-        stringResource(R.string.this_text_is_available_in_settings),
-        color = MaterialTheme.colors.onBackground
-      )
-      Icon(
-        Icons.Outlined.Settings,
-        stringResource(R.string.icon_descr_settings),
-        tint = MaterialTheme.colors.onBackground,
-        modifier = Modifier.clickable(onClick = { scaffoldCtrl.toggleDrawer() })
-      )
-    }
-  }
-}
-
 @Composable
 fun ChatListToolbar(scaffoldCtrl: ScaffoldController) {
   Row(

apps/android/app/src/main/java/chat/simplex/app/views/helpers/LocalAuthentication.kt

@@ -0,0 +1,112 @@
+package chat.simplex.app.views.helpers
+
+import android.content.Context
+import android.os.Build.VERSION.SDK_INT
+import android.widget.Toast
+import androidx.biometric.BiometricManager
+import androidx.biometric.BiometricManager.Authenticators.*
+import androidx.biometric.BiometricPrompt
+import androidx.core.content.ContextCompat
+import androidx.fragment.app.FragmentActivity
+import chat.simplex.app.R
+
+sealed class LAResult {
+  object Success: LAResult()
+  class Error(val errString: CharSequence): LAResult()
+  object Failed: LAResult()
+  object Unavailable: LAResult()
+}
+
+fun authenticate(
+  promptTitle: String,
+  promptSubtitle: String,
+  activity: FragmentActivity,
+  completed: (LAResult) -> Unit
+) {
+  when {
+    SDK_INT in 28..29 ->
+      // KeyguardManager.isDeviceSecure()? https://developer.android.com/training/sign-in/biometric-auth#declare-supported-authentication-types
+      authenticateWithBiometricManager(promptTitle, promptSubtitle, activity, completed, BIOMETRIC_WEAK or DEVICE_CREDENTIAL)
+    SDK_INT > 29 ->
+      authenticateWithBiometricManager(promptTitle, promptSubtitle, activity, completed, BIOMETRIC_STRONG or DEVICE_CREDENTIAL)
+    else ->
+      completed(LAResult.Unavailable)
+  }
+}
+
+private fun authenticateWithBiometricManager(
+  promptTitle: String,
+  promptSubtitle: String,
+  activity: FragmentActivity,
+  completed: (LAResult) -> Unit,
+  authenticators: Int
+) {
+  val biometricManager = BiometricManager.from(activity)
+  when (biometricManager.canAuthenticate(authenticators)) {
+    BiometricManager.BIOMETRIC_SUCCESS -> {
+      val executor = ContextCompat.getMainExecutor(activity)
+      val biometricPrompt = BiometricPrompt(
+        activity,
+        executor,
+        object: BiometricPrompt.AuthenticationCallback() {
+          override fun onAuthenticationError(
+            errorCode: Int,
+            errString: CharSequence
+          ) {
+            super.onAuthenticationError(errorCode, errString)
+            completed(LAResult.Error(errString))
+          }
+
+          override fun onAuthenticationSucceeded(
+            result: BiometricPrompt.AuthenticationResult
+          ) {
+            super.onAuthenticationSucceeded(result)
+            completed(LAResult.Success)
+          }
+
+          override fun onAuthenticationFailed() {
+            super.onAuthenticationFailed()
+            completed(LAResult.Failed)
+          }
+        }
+      )
+      val promptInfo = BiometricPrompt.PromptInfo.Builder()
+        .setTitle(promptTitle)
+        .setSubtitle(promptSubtitle)
+        .setAllowedAuthenticators(authenticators)
+        .setConfirmationRequired(false)
+        .build()
+      biometricPrompt.authenticate(promptInfo)
+    }
+    else -> {
+      completed(LAResult.Unavailable)
+    }
+  }
+}
+
+fun laTurnedOnAlert() = AlertManager.shared.showAlertMsg(
+  generalGetString(R.string.auth_turned_on),
+  generalGetString(R.string.auth_turned_on_desc)
+)
+
+fun laErrorToast(context: Context, errString: CharSequence) = Toast.makeText(
+  context,
+  if (errString.isNotEmpty()) String.format(generalGetString(R.string.auth_error_w_desc), errString) else generalGetString(R.string.auth_error),
+  Toast.LENGTH_SHORT
+).show()
+
+fun laFailedToast(context: Context) = Toast.makeText(
+  context,
+  generalGetString(R.string.auth_failed),
+  Toast.LENGTH_SHORT
+).show()
+
+fun laUnavailableInstructionAlert() = AlertManager.shared.showAlertMsg(
+  generalGetString(R.string.auth_unavailable),
+  generalGetString(R.string.auth_unavailable_instruction_desc)
+)
+
+fun laUnavailableTurningOffAlert() = AlertManager.shared.showAlertMsg(
+  generalGetString(R.string.auth_unavailable),
+  generalGetString(R.string.auth_unavailable_turning_off_desc)
+)

apps/android/app/src/main/java/chat/simplex/app/views/usersettings/SettingsView.kt

@@ -28,20 +28,25 @@ import chat.simplex.app.views.helpers.*
 import chat.simplex.app.views.onboarding.SimpleXInfo
 
 @Composable
-fun SettingsView(chatModel: ChatModel) {
+fun SettingsView(chatModel: ChatModel, setPerformLA: (Boolean) -> Unit) {
   val user = chatModel.currentUser.value
+
+  fun setRunServiceInBackground(on: Boolean) {
+    chatModel.controller.setRunServiceInBackground(on)
+    if (on && !chatModel.controller.isIgnoringBatteryOptimizations(chatModel.controller.appContext)) {
+      chatModel.controller.setBackgroundServiceNoticeShown(false)
+    }
+    chatModel.controller.showBackgroundServiceNoticeIfNeeded()
+    chatModel.runServiceInBackground.value = on
+  }
+
   if (user != null) {
     SettingsLayout(
       profile = user.profile,
       runServiceInBackground = chatModel.runServiceInBackground,
-      setRunServiceInBackground = { on ->
-        chatModel.controller.setRunServiceInBackground(on)
-        if (on && !chatModel.controller.isIgnoringBatteryOptimizations(chatModel.controller.appContext)) {
-          chatModel.controller.setBackgroundServiceNoticeShown(false)
-        }
-        chatModel.controller.showBackgroundServiceNoticeIfNeeded()
-        chatModel.runServiceInBackground.value = on
-      },
+      setRunServiceInBackground = ::setRunServiceInBackground,
+      performLA = chatModel.performLA,
+      setPerformLA = setPerformLA,
       showModal = { modalView -> { ModalManager.shared.showModal { modalView(chatModel) } } },
       showCustomModal = { modalView -> { ModalManager.shared.showCustomModal { close -> modalView(chatModel, close) } } },
       showTerminal = { ModalManager.shared.showCustomModal { close -> TerminalView(chatModel, close) } }
@@ -58,6 +63,8 @@ fun SettingsLayout(
   profile: Profile,
   runServiceInBackground: MutableState<Boolean>,
   setRunServiceInBackground: (Boolean) -> Unit,
+  performLA: MutableState<Boolean>,
+  setPerformLA: (Boolean) -> Unit,
   showModal: (@Composable (ChatModel) -> Unit) -> (() -> Unit),
   showCustomModal: (@Composable (ChatModel, () -> Unit) -> Unit) -> (() -> Unit),
   showTerminal: () -> Unit,
@@ -168,7 +175,8 @@ fun SettingsLayout(
           stringResource(R.string.private_notifications), Modifier
             .padding(end = 24.dp)
             .fillMaxWidth()
-            .weight(1F))
+            .weight(1F)
+        )
         Switch(
           checked = runServiceInBackground.value,
           onCheckedChange = { setRunServiceInBackground(it) },
@@ -180,6 +188,29 @@ fun SettingsLayout(
         )
       }
       Divider(Modifier.padding(horizontal = 8.dp))
+      SettingsSectionView() {
+        Icon(
+          Icons.Outlined.Lock,
+          contentDescription = stringResource(R.string.chat_lock),
+        )
+        Spacer(Modifier.padding(horizontal = 4.dp))
+        Text(
+          stringResource(R.string.chat_lock), Modifier
+            .padding(end = 24.dp)
+            .fillMaxWidth()
+            .weight(1F)
+        )
+        Switch(
+          checked = performLA.value,
+          onCheckedChange = { setPerformLA(it) },
+          colors = SwitchDefaults.colors(
+            checkedThumbColor = MaterialTheme.colors.primary,
+            uncheckedThumbColor = HighOrLowlight
+          ),
+          modifier = Modifier.padding(end = 8.dp)
+        )
+      }
+      Divider(Modifier.padding(horizontal = 8.dp))
       SettingsSectionView(showTerminal) {
         Icon(
           painter = painterResource(id = R.drawable.ic_outline_terminal),
@@ -246,8 +277,10 @@ fun PreviewSettingsLayout() {
       profile = Profile.sampleData,
       runServiceInBackground = remember { mutableStateOf(true) },
       setRunServiceInBackground = {},
-      showModal = {{}},
-      showCustomModal = {{}},
+      performLA = remember { mutableStateOf(false) },
+      setPerformLA = {},
+      showModal = { {} },
+      showCustomModal = { {} },
       showTerminal = {},
 //      showVideoChatPrototype = {}
     )

apps/android/app/src/main/res/values-ru/strings.xml

@@ -46,13 +46,13 @@
     <string name="connection_error_auth_desc">Возможно, ваш контакт удалил ссылку, или она уже была использована. Если это не так, то это может быть ошибкой - пожалуйста, сообщите нам об этом.\nЧтобы установить соединение, попросите ваш контакт создать еще одну ссылку и проверьте ваше соединение с сетью.</string>
     <string name="cannot_delete_contact">Невозможно удалить контакт!</string>
     <string name="contact_cannot_be_deleted_as_they_are_in_groups">Контакт <xliff:g id="contactName" example="Jane Doe">%1$s!</xliff:g> не может быть удален, так как является членом групп(ы) <xliff:g id="groups" example="[team, chess club]">%2$s</xliff:g>.</string>
-    <string name="icon_descr_instant_notifications">Мгновенные уведомления</string>
     <string name="error_deleting_contact">Ошибка удаления контакта</string>
     <string name="error_deleting_group">Ошибка удаления группы</string>
     <string name="error_deleting_contact_request">Ошибка удаления запроса</string>
     <string name="error_deleting_pending_contact_connection">Ошибка удаления ожидаемого соединения</string>
 
     <!-- background service notice - SimpleXAPI.kt -->
+    <string name="icon_descr_instant_notifications">Мгновенные уведомления</string>
     <string name="private_instant_notifications">Приватные мгновенные уведомления!</string>
     <string name="private_instant_notifications_disabled">Приватные уведомления выключены!</string>
     <string name="to_preserve_privacy_simplex_has_background_service_instead_of_push_notifications_it_uses_a_few_pc_battery">Чтобы защитить ваши личные данные, вместо уведомлений от сервера приложение запускает <b>фоновый сервис <xliff:g id="appName">SimpleX</xliff:g></b>, который потребляет несколько процентов батареи в день.</string>
@@ -64,6 +64,26 @@
     <string name="simplex_service_notification_title"><xliff:g id="appNameFull">SimpleX Chat</xliff:g> сервис</string>
     <string name="simplex_service_notification_text">Приём сообщений…</string>
 
+    <!-- local authentication notice - SimpleXAPI.kt -->
+    <string name="la_notice_title">Блокировка SimpleX</string>
+    <string name="la_notice_text">Чтобы защитить вашу информацию, включите блокировку <xliff:g id="appNameFull">SimpleX Chat</xliff:g>.\nВам будет нужно пройти аутентификацию для включения блокировки.</string>
+    <string name="la_notice_turn_on">Включить</string>
+
+    <!-- LocalAuthentication.kt -->
+    <string name="auth_turned_on">Блокировка SimpleX включена</string>
+    <string name="auth_turned_on_desc">Вы будете аутентифицированы при запуске и возобновлении приложения, которое было 30 секунд в фоновом режиме.</string>
+    <string name="auth_access_chats">Разблокировать SimpleX</string>
+    <string name="auth_log_in_using_credential">Пройдите аутентификацию</string>
+    <string name="auth_enable">Включить блокировку SimpleX</string>
+    <string name="auth_disable">Отключить блокировку SimpleX</string>
+    <string name="auth_confirm_credential">Пройдите аутентификацию</string>
+    <string name="auth_error">Ошибка аутентификации</string>
+    <string name="auth_error_w_desc">Ошибка аутентификации: <xliff:g id="desc">%1$s</xliff:g></string>
+    <string name="auth_failed">Ошибка аутентификации</string>
+    <string name="auth_unavailable">Аутентификация недоступна</string>
+    <string name="auth_unavailable_instruction_desc">На устройстве не включена аутентификация. Вы можете включить блокировку SimpleX в Настройках после включения аутентификации.</string>
+    <string name="auth_unavailable_turning_off_desc">На устройстве выключена аутентификация. Отключение блокировки SimpleX Chat.</string>
+
     <!-- Chat Actions - ChatItemView.kt (and general) -->
     <string name="reply_verb">Ответить</string>
     <string name="share_verb">Поделиться</string>
@@ -219,8 +239,7 @@
     <string name="if_you_cannot_meet_in_person_scan_QR_in_video_call_or_ask_for_invitation_link">Если вы не можете встретиться лично, вы можете <b>сосканировать QR код во время видеозвонка</b>, или ваш контакт может отправить вам ссылку.</string>
     <string name="share_invitation_link">Поделиться ссылкой</string>
     <string name="paste_connection_link_below_to_connect">Чтобы соединиться, вставьте в это поле ссылку, полученную от вашего контакта.</string>
-
-
+    
     <!-- settings - SettingsView.kt -->
     <string name="your_settings">Настройки</string>
     <string name="your_simplex_contact_address">Ваш <xliff:g id="appName">SimpleX</xliff:g> адрес</string>
@@ -231,6 +250,7 @@
     <string name="chat_with_the_founder">Соединиться с разработчиками</string>
     <string name="send_us_an_email">Отправить email</string>
     <string name="private_notifications">Приватные уведомления</string>
+    <string name="chat_lock">Блокировка SimpleX</string>
     <string name="chat_console">Консоль</string>
     <string name="smp_servers">SMP серверы</string>
     <string name="install_simplex_chat_for_terminal"><font color="#0088ff"><xliff:g id="appNameFull">SimpleX Chat</xliff:g> для терминала</font></string>

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

@@ -46,13 +46,13 @@
   <string name="connection_error_auth_desc">Unless your contact deleted the connection or this link was already used, it might be a bug - please report it.\nTo connect, please ask your contact to create another connection link and check that you have a stable network connection.</string>
   <string name="cannot_delete_contact">Can\'t delete contact!</string>
   <string name="contact_cannot_be_deleted_as_they_are_in_groups">Contact <xliff:g id="contactName" example="Jane Doe">%1$s!</xliff:g> cannot be deleted, they are a member of the group(s) <xliff:g id="groups" example="[team, chess club]">%2$s</xliff:g>.</string>
-  <string name="icon_descr_instant_notifications">Instant notifications</string>
   <string name="error_deleting_contact">Error deleting contact</string>
   <string name="error_deleting_group">Error deleting group</string>
   <string name="error_deleting_contact_request">Error deleting contact request</string>
   <string name="error_deleting_pending_contact_connection">Error deleting pending contact connection</string>
 
   <!-- background service notice - SimpleXAPI.kt -->
+  <string name="icon_descr_instant_notifications">Instant notifications</string>
   <string name="private_instant_notifications">Private instant notifications!</string>
   <string name="private_instant_notifications_disabled">Private notifications disabled!</string>
   <string name="to_preserve_privacy_simplex_has_background_service_instead_of_push_notifications_it_uses_a_few_pc_battery">To preserve your privacy, instead of push notifications the app has a <b><xliff:g id="appName">SimpleX</xliff:g> background service</b> – it uses a few percent of the battery per day.</string>
@@ -64,6 +64,26 @@
   <string name="simplex_service_notification_title"><xliff:g id="appNameFull">SimpleX Chat</xliff:g> service</string>
   <string name="simplex_service_notification_text">Receiving messages…</string>
 
+  <!-- local authentication notice - SimpleXAPI.kt -->
+  <string name="la_notice_title">SimpleX Lock</string>
+  <string name="la_notice_text">To protect your information, turn on SimpleX Lock.\nYou will be prompted to complete authentication before this feature is enabled.</string>
+  <string name="la_notice_turn_on">Turn on</string>
+
+  <!-- LocalAuthentication.kt -->
+  <string name="auth_turned_on">SimpleX Lock turned on</string>
+  <string name="auth_turned_on_desc">You will be required to authenticate when you start or resume the app after 30 seconds in background.</string>
+  <string name="auth_access_chats">Access chats</string>
+  <string name="auth_log_in_using_credential">Log in using your credential</string>
+  <string name="auth_enable">Enable SimpleX Lock</string>
+  <string name="auth_disable">Disable SimpleX Lock</string>
+  <string name="auth_confirm_credential">Confirm your credential</string>
+  <string name="auth_error">Authentication error</string>
+  <string name="auth_error_w_desc">Authentication error: <xliff:g id="desc">%1$s</xliff:g></string>
+  <string name="auth_failed">Authentication failed</string>
+  <string name="auth_unavailable">Authentication unavailable</string>
+  <string name="auth_unavailable_instruction_desc">Device authentication is not enabled. You can turn on SimpleX Lock via Settings, once you enable device authentication.</string>
+  <string name="auth_unavailable_turning_off_desc">Device authentication is disabled. Turning off SimpleX Lock.</string>
+
   <!-- Chat Actions - ChatItemView.kt (and general) -->
   <string name="reply_verb">Reply</string>
   <string name="share_verb">Share</string>
@@ -236,6 +256,7 @@
   <string name="chat_with_the_founder">Connect to the developers</string>
   <string name="send_us_an_email">Send us email</string>
   <string name="private_notifications">Private notifications</string>
+  <string name="chat_lock">SimpleX Lock</string>
   <string name="chat_console">Chat console</string>
   <string name="smp_servers">SMP servers</string>
   <string name="install_simplex_chat_for_terminal">Install <font color="#0088ff"><xliff:g id="appNameFull">SimpleX Chat</xliff:g> for terminal</font></string>