feat(auth): add phone MFA

melos.yaml

@@ -186,8 +186,9 @@ scripts:
 
   generate:pigeon:
     run: |
-      melos exec -- "flutter pub run pigeon --input ./pigeons/messages.dart"
-      melos run generate:pigeon:macos
+      melos exec -- "flutter pub run pigeon --input ./pigeons/messages.dart" && \
+      melos run generate:pigeon:macos --no-select && \
+      melos run format --no-select
     select-package:
       file-exists: 'pigeons/messages.dart'
     description: Generate the pigeon messages for all the supported packages.

packages/firebase_auth/analysis_options.yaml

@@ -0,0 +1,11 @@
+# Copyright 2021 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# in the LICENSE file.
+
+include: ../../analysis_options.yaml
+
+analyzer:
+  # TODO(Lyokone): not working if added on the root analysis file
+  exclude:
+    - firebase_auth_platform_interface/lib/src/pigeon/messages.pigeon.dart
+    - firebase_auth_platform_interface/test/pigeon/test_api.dart

packages/firebase_auth/firebase_auth/android/src/main/java/io/flutter/plugins/firebase/auth/Constants.java

@@ -83,4 +83,10 @@ public class Constants {
   public static final String APP_VERIFICATION_DISABLED_FOR_TESTING =
       "appVerificationDisabledForTesting";
   public static final String FORCE_RECAPTCHA_FLOW = "forceRecaptchaFlow";
+
+  // MultiFactor
+  public static final String MULTI_FACTOR_HINTS = "multiFactorHints";
+  public static final String MULTI_FACTOR_SESSION_ID = "multiFactorSessionId";
+  public static final String MULTI_FACTOR_RESOLVER_ID = "multiFactorResolverId";
+  public static final String MULTI_FACTOR_INFO = "multiFactorInfo";
 }

packages/firebase_auth/firebase_auth/android/src/main/java/io/flutter/plugins/firebase/auth/FlutterFirebaseAuthPlugin.java

@@ -28,19 +28,28 @@
 import com.google.firebase.auth.FacebookAuthProvider;
 import com.google.firebase.auth.FirebaseAuth;
 import com.google.firebase.auth.FirebaseAuthException;
+import com.google.firebase.auth.FirebaseAuthMultiFactorException;
 import com.google.firebase.auth.FirebaseAuthProvider;
 import com.google.firebase.auth.FirebaseUser;
 import com.google.firebase.auth.FirebaseUserMetadata;
 import com.google.firebase.auth.GetTokenResult;
 import com.google.firebase.auth.GithubAuthProvider;
 import com.google.firebase.auth.GoogleAuthProvider;
+import com.google.firebase.auth.MultiFactor;
+import com.google.firebase.auth.MultiFactorAssertion;
+import com.google.firebase.auth.MultiFactorInfo;
+import com.google.firebase.auth.MultiFactorResolver;
+import com.google.firebase.auth.MultiFactorSession;
 import com.google.firebase.auth.OAuthProvider;
 import com.google.firebase.auth.PhoneAuthCredential;
 import com.google.firebase.auth.PhoneAuthProvider;
+import com.google.firebase.auth.PhoneMultiFactorGenerator;
+import com.google.firebase.auth.PhoneMultiFactorInfo;
 import com.google.firebase.auth.SignInMethodQueryResult;
 import com.google.firebase.auth.TwitterAuthProvider;
 import com.google.firebase.auth.UserInfo;
 import com.google.firebase.auth.UserProfileChangeRequest;
+import com.google.firebase.internal.api.FirebaseNoSignedInUserException;
 import io.flutter.embedding.engine.plugins.FlutterPlugin;
 import io.flutter.embedding.engine.plugins.activity.ActivityAware;
 import io.flutter.embedding.engine.plugins.activity.ActivityPluginBinding;
@@ -63,7 +72,12 @@
 
 /** Flutter plugin for Firebase Auth. */
 public class FlutterFirebaseAuthPlugin
-    implements FlutterFirebasePlugin, MethodCallHandler, FlutterPlugin, ActivityAware {
+    implements FlutterFirebasePlugin,
+        MethodCallHandler,
+        FlutterPlugin,
+        ActivityAware,
+        GeneratedAndroidFirebaseAuth.MultiFactorUserHostApi,
+        GeneratedAndroidFirebaseAuth.MultiFactoResolverHostApi {
 
   private static final String METHOD_CHANNEL_NAME = "plugins.flutter.io/firebase_auth";
 
@@ -98,6 +112,8 @@ private void initInstance(BinaryMessenger messenger) {
     registerPlugin(METHOD_CHANNEL_NAME, this);
     channel = new MethodChannel(messenger, METHOD_CHANNEL_NAME);
     channel.setMethodCallHandler(this);
+    GeneratedAndroidFirebaseAuth.MultiFactorUserHostApi.setup(messenger, this);
+    GeneratedAndroidFirebaseAuth.MultiFactoResolverHostApi.setup(messenger, this);
 
     this.messenger = messenger;
   }
@@ -112,6 +128,8 @@ public void onDetachedFromEngine(@NonNull FlutterPluginBinding binding) {
     channel.setMethodCallHandler(null);
     channel = null;
     messenger = null;
+    GeneratedAndroidFirebaseAuth.MultiFactorUserHostApi.setup(null, this);
+    GeneratedAndroidFirebaseAuth.MultiFactoResolverHostApi.setup(null, this);
 
     removeEventListeners();
   }
@@ -159,6 +177,11 @@ private FirebaseUser getCurrentUser(Map<String, Object> arguments) {
     return FirebaseAuth.getInstance(app).getCurrentUser();
   }
 
+  private FirebaseUser getCurrentUser(String appName) {
+    FirebaseApp app = FirebaseApp.getInstance(appName);
+    return FirebaseAuth.getInstance(app).getCurrentUser();
+  }
+
   private AuthCredential getCredential(Map<String, Object> arguments)
       throws FlutterFirebaseAuthPluginException {
     @SuppressWarnings("unchecked")
@@ -790,13 +813,79 @@ private Task<Map<String, Object>> signInWithEmailAndPassword(Map<String, Object>
 
             taskCompletionSource.setResult(parseAuthResult(authResult));
           } catch (Exception e) {
-            taskCompletionSource.setException(e);
+            if (e.getCause() instanceof FirebaseAuthMultiFactorException) {
+              final FirebaseAuthMultiFactorException multiFactorException =
+                  (FirebaseAuthMultiFactorException) e.getCause();
+              Map<String, Object> output = new HashMap<>();
+
+              MultiFactorResolver multiFactorResolver = multiFactorException.getResolver();
+              final List<MultiFactorInfo> hints = multiFactorResolver.getHints();
+
+              final MultiFactorSession session = multiFactorResolver.getSession();
+              final String sessionId = UUID.randomUUID().toString();
+              multiFactorSessionMap.put(sessionId, session);
+
+              final String resolverId = UUID.randomUUID().toString();
+              multiFactorResolverMap.put(resolverId, multiFactorResolver);
+
+              final List<Map<String, Object>> pigeonHints = multiFactorInfoToMap(hints);
+
+              output.put(Constants.APP_NAME, getAuth(arguments).getApp().getName());
+
+              output.put(Constants.MULTI_FACTOR_HINTS, pigeonHints);
+
+              output.put(Constants.MULTI_FACTOR_SESSION_ID, sessionId);
+              output.put(Constants.MULTI_FACTOR_RESOLVER_ID, resolverId);
+
+              taskCompletionSource.setException(
+                  new FlutterFirebaseAuthPluginException(
+                      multiFactorException.getErrorCode(),
+                      multiFactorException.getLocalizedMessage(),
+                      output));
+            } else {
+              taskCompletionSource.setException(e);
+            }
           }
         });
 
     return taskCompletionSource.getTask();
   }
 
+  private List<GeneratedAndroidFirebaseAuth.PigeonMultiFactorInfo> multiFactorInfoToPigeon(
+      List<MultiFactorInfo> hints) {
+    List<GeneratedAndroidFirebaseAuth.PigeonMultiFactorInfo> pigeonHints = new ArrayList<>();
+    for (MultiFactorInfo info : hints) {
+      if (info instanceof PhoneMultiFactorInfo) {
+        pigeonHints.add(
+            new GeneratedAndroidFirebaseAuth.PigeonMultiFactorInfo.Builder()
+                .setPhoneNumber(((PhoneMultiFactorInfo) info).getPhoneNumber())
+                .setDisplayName(info.getDisplayName())
+                .setEnrollmentTimestamp((double) info.getEnrollmentTimestamp())
+                .setUid(info.getUid())
+                .setFactorId(info.getFactorId())
+                .build());
+
+      } else {
+        pigeonHints.add(
+            new GeneratedAndroidFirebaseAuth.PigeonMultiFactorInfo.Builder()
+                .setDisplayName(info.getDisplayName())
+                .setEnrollmentTimestamp((double) info.getEnrollmentTimestamp())
+                .setUid(info.getUid())
+                .setFactorId(info.getFactorId())
+                .build());
+      }
+    }
+    return pigeonHints;
+  }
+
+  private List<Map<String, Object>> multiFactorInfoToMap(List<MultiFactorInfo> hints) {
+    List<Map<String, Object>> pigeonHints = new ArrayList<>();
+    for (GeneratedAndroidFirebaseAuth.PigeonMultiFactorInfo info : multiFactorInfoToPigeon(hints)) {
+      pigeonHints.add(info.toMap());
+    }
+    return pigeonHints;
+  }
+
   private Task<Map<String, Object>> signInWithEmailLink(Map<String, Object> arguments) {
     TaskCompletionSource<Map<String, Object>> taskCompletionSource = new TaskCompletionSource<>();
 
@@ -883,10 +972,36 @@ private Task<String> verifyPhoneNumber(Map<String, Object> arguments) {
             String eventChannelName =
                 METHOD_CHANNEL_NAME + "/phone/" + UUID.randomUUID().toString();
             EventChannel channel = new EventChannel(messenger, eventChannelName);
+
+            final String multiFactorSessionId =
+                (String) arguments.get(Constants.MULTI_FACTOR_SESSION_ID);
+            MultiFactorSession multiFactorSession = null;
+
+            if (multiFactorSessionId != null) {
+              multiFactorSession = multiFactorSessionMap.get(multiFactorSessionId);
+            }
+
+            final String multiFactorInfoId = (String) arguments.get(Constants.MULTI_FACTOR_INFO);
+            PhoneMultiFactorInfo multiFactorInfo = null;
+
+            if (multiFactorInfoId != null) {
+              for (String resolverId : multiFactorResolverMap.keySet()) {
+                for (MultiFactorInfo info : multiFactorResolverMap.get(resolverId).getHints()) {
+                  if (info.getUid().equals(multiFactorInfoId)
+                      && info instanceof PhoneMultiFactorInfo) {
+                    multiFactorInfo = (PhoneMultiFactorInfo) info;
+                    break;
+                  }
+                }
+              }
+            }
+
             PhoneNumberVerificationStreamHandler handler =
                 new PhoneNumberVerificationStreamHandler(
                     getActivity(),
                     arguments,
+                    multiFactorSession,
+                    multiFactorInfo,
                     credential -> {
                       int hashCode = credential.hashCode();
                       authCredentials.put(hashCode, credential);
@@ -1573,4 +1688,145 @@ private void removeEventListeners() {
     }
     streamHandlers.clear();
   }
+
+  // Map an app id to a map of user id to a MultiFactorUser object.
+  private final Map<String, Map<String, MultiFactor>> multiFactorUserMap = new HashMap<>();
+
+  // Map an id to a MultiFactorSession object.
+  private final Map<String, MultiFactorSession> multiFactorSessionMap = new HashMap<>();
+
+  // Map an id to a MultiFactorSession object.
+  private final Map<String, MultiFactorResolver> multiFactorResolverMap = new HashMap<>();
+
+  private MultiFactor getAppMultiFactor(
+      @NonNull String appName, GeneratedAndroidFirebaseAuth.Result result) {
+    final FirebaseUser currentUser = getCurrentUser(appName);
+    if (currentUser == null) {
+      result.error(new FirebaseNoSignedInUserException("No user is signed in"));
+    }
+    if (multiFactorUserMap.get(appName) == null) {
+      multiFactorUserMap.put(appName, new HashMap<>());
+    }
+
+    final Map<String, MultiFactor> appMultiFactorUser = multiFactorUserMap.get(appName);
+    if (appMultiFactorUser.get(currentUser.getUid()) == null) {
+      appMultiFactorUser.put(currentUser.getUid(), currentUser.getMultiFactor());
+    }
+
+    final MultiFactor multiFactor = appMultiFactorUser.get(currentUser.getUid());
+    return multiFactor;
+  }
+
+  @Override
+  public void enrollPhone(
+      @NonNull String appName,
+      @NonNull GeneratedAndroidFirebaseAuth.PigeonPhoneMultiFactorAssertion assertion,
+      @Nullable String displayName,
+      GeneratedAndroidFirebaseAuth.Result<Void> result) {
+    final MultiFactor multiFactor = getAppMultiFactor(appName, result);
+
+    PhoneAuthCredential credential =
+        PhoneAuthProvider.getCredential(
+            assertion.getVerificationId(), assertion.getVerificationCode());
+
+    MultiFactorAssertion multiFactorAssertion = PhoneMultiFactorGenerator.getAssertion(credential);
+
+    multiFactor
+        .enroll(multiFactorAssertion, displayName)
+        .addOnCompleteListener(
+            task -> {
+              if (task.isSuccessful()) {
+                result.success(null);
+              } else {
+                result.error(task.getException());
+              }
+            });
+  }
+
+  @Override
+  public void getSession(
+      @NonNull String appName,
+      GeneratedAndroidFirebaseAuth.Result<GeneratedAndroidFirebaseAuth.PigeonMultiFactorSession>
+          result) {
+    final MultiFactor multiFactor = getAppMultiFactor(appName, result);
+
+    multiFactor
+        .getSession()
+        .addOnCompleteListener(
+            task -> {
+              if (task.isSuccessful()) {
+                final MultiFactorSession sessionResult = task.getResult();
+                final String id = UUID.randomUUID().toString();
+                multiFactorSessionMap.put(id, sessionResult);
+                result.success(
+                    new GeneratedAndroidFirebaseAuth.PigeonMultiFactorSession.Builder()
+                        .setId(id)
+                        .build());
+              } else {
+                Exception exception = task.getException();
+                result.error(exception);
+              }
+            });
+  }
+
+  @Override
+  public void unenroll(
+      @NonNull String appName,
+      @Nullable String factorUid,
+      GeneratedAndroidFirebaseAuth.Result<Void> result) {
+    final MultiFactor multiFactor = getAppMultiFactor(appName, result);
+
+    multiFactor
+        .unenroll(factorUid)
+        .addOnCompleteListener(
+            task -> {
+              if (task.isSuccessful()) {
+                result.success(null);
+              } else {
+                result.error(task.getException());
+              }
+            });
+  }
+
+  @Override
+  public void getEnrolledFactors(
+      @NonNull String appName,
+      GeneratedAndroidFirebaseAuth.Result<List<GeneratedAndroidFirebaseAuth.PigeonMultiFactorInfo>>
+          result) {
+    final MultiFactor multiFactor = getAppMultiFactor(appName, result);
+
+    final List<MultiFactorInfo> factors = multiFactor.getEnrolledFactors();
+
+    final List<GeneratedAndroidFirebaseAuth.PigeonMultiFactorInfo> resultFactors =
+        multiFactorInfoToPigeon(factors);
+
+    result.success(resultFactors);
+  }
+
+  @Override
+  public void resolveSignIn(
+      @NonNull String resolverId,
+      @NonNull GeneratedAndroidFirebaseAuth.PigeonPhoneMultiFactorAssertion assertion,
+      GeneratedAndroidFirebaseAuth.Result<Map<String, Object>> result) {
+    final MultiFactorResolver resolver = multiFactorResolverMap.get(resolverId);
+
+    PhoneAuthCredential credential =
+        PhoneAuthProvider.getCredential(
+            assertion.getVerificationId(), assertion.getVerificationCode());
+
+    MultiFactorAssertion multiFactorAssertion = PhoneMultiFactorGenerator.getAssertion(credential);
+
+    resolver
+        .resolveSignIn(multiFactorAssertion)
+        .addOnCompleteListener(
+            task -> {
+              if (task.isSuccessful()) {
+                final AuthResult authResult = task.getResult();
+                result.success(parseAuthResult(authResult));
+              } else {
+                Exception exception = task.getException();
+                result.error(exception);
+              }
+            });
+  }
 }

packages/firebase_auth/firebase_auth/android/src/main/java/io/flutter/plugins/firebase/auth/FlutterFirebaseAuthPluginException.java

@@ -24,6 +24,15 @@ public class FlutterFirebaseAuthPluginException extends Exception {
     this.message = message;
   }
 
+  FlutterFirebaseAuthPluginException(
+      @NonNull String code, @NonNull String message, @NonNull Map<String, Object> additionalData) {
+    super(message, null);
+
+    this.code = code;
+    this.message = message;
+    this.additionalData = additionalData;
+  }
+
   FlutterFirebaseAuthPluginException(@NonNull Exception nativeException, Throwable cause) {
     super(nativeException.getMessage(), cause);