fix: SSO on web hopefully

lib/pages/homeserver_picker.dart

@@ -1,12 +1,21 @@
+import 'dart:async';
+
 import 'package:famedlysdk/famedlysdk.dart';
 import 'package:fluffychat/pages/views/homeserver_picker_view.dart';
 import 'package:fluffychat/widgets/matrix.dart';
 import 'package:fluffychat/config/app_config.dart';
 import 'package:fluffychat/config/setting_keys.dart';
+import 'package:flutter/foundation.dart';
 import 'package:flutter_gen/gen_l10n/l10n.dart';
 import 'package:flutter/material.dart';
 import '../utils/localized_exception_extension.dart';
 import 'package:vrouter/vrouter.dart';
+import 'package:fluffychat/utils/platform_infos.dart';
+import 'package:future_loading_dialog/future_loading_dialog.dart';
+import 'package:uni_links/uni_links.dart';
+import 'package:universal_html/html.dart' as html;
+
+import '../main.dart';
 
 class HomeserverPicker extends StatefulWidget {
   @override
@@ -18,6 +27,55 @@ class HomeserverPickerController extends State<HomeserverPicker> {
   String domain = AppConfig.defaultHomeserver;
   final TextEditingController homeserverController =
       TextEditingController(text: AppConfig.defaultHomeserver);
+  StreamSubscription _intentDataStreamSubscription;
+
+  void _loginWithToken(String token) {
+    if (token?.isEmpty ?? true) return;
+    showFutureLoadingDialog(
+      context: context,
+      future: () => Matrix.of(context).client.login(
+            type: AuthenticationTypes.token,
+            token: token,
+            initialDeviceDisplayName: PlatformInfos.clientName,
+          ),
+    );
+  }
+
+  void _processIncomingUris(String text) async {
+    if (text == null || !text.startsWith(AppConfig.appOpenUrlScheme)) return;
+    VRouter.of(context).push('/home');
+    final token = Uri.parse(text).queryParameters['loginToken'];
+    if (token != null) _loginWithToken(token);
+  }
+
+  void _initReceiveUri() {
+    if (!PlatformInfos.isMobile) return;
+    // For receiving shared Uris
+    _intentDataStreamSubscription = linkStream.listen(_processIncomingUris);
+    if (FluffyChatApp.gotInitialLink == false) {
+      FluffyChatApp.gotInitialLink = true;
+      getInitialLink().then(_processIncomingUris);
+    }
+  }
+
+  @override
+  void initState() {
+    super.initState();
+    _initReceiveUri();
+    if (kIsWeb) {
+      WidgetsBinding.instance.addPostFrameCallback((_) {
+        final token =
+            Uri.parse(html.window.location.href).queryParameters['loginToken'];
+        _loginWithToken(token);
+      });
+    }
+  }
+
+  @override
+  void dispose() {
+    super.dispose();
+    _intentDataStreamSubscription?.cancel();
+  }
 
   /// Starts an analysis of the given homeserver. It uses the current domain and
   /// makes sure that it is prefixed with https. Then it searches for the

lib/pages/sign_up.dart

@@ -3,19 +3,14 @@ import 'dart:async';
 import 'package:famedlysdk/famedlysdk.dart';
 import 'package:fluffychat/config/app_config.dart';
 import 'package:fluffychat/pages/views/sign_up_view.dart';
-import 'package:fluffychat/utils/platform_infos.dart';
+import 'package:fluffychat/utils/famedlysdk_store.dart';
 
 import 'package:fluffychat/widgets/matrix.dart';
 import 'package:flutter/cupertino.dart';
 import 'package:flutter/foundation.dart';
 import 'package:flutter/material.dart';
-import 'package:future_loading_dialog/future_loading_dialog.dart';
-import 'package:uni_links/uni_links.dart';
 import 'package:url_launcher/url_launcher.dart';
 import 'package:universal_html/html.dart' as html;
-import 'package:vrouter/vrouter.dart';
-
-import '../main.dart';
 
 class SignUp extends StatefulWidget {
   @override
@@ -25,7 +20,7 @@ class SignUp extends StatefulWidget {
 class SignUpController extends State<SignUp> {
   Map<String, dynamic> _rawLoginTypes;
   bool registrationSupported;
-  StreamSubscription _intentDataStreamSubscription;
+
   List<IdentityProvider> get identityProviders {
     if (!ssoLoginSupported) return [];
     final rawProviders = _rawLoginTypes.tryGetList('flows').singleWhere(
@@ -36,54 +31,6 @@ class SignUpController extends State<SignUp> {
         .toList();
   }
 
-  void _loginWithToken(String token) {
-    if (token?.isEmpty ?? true) return;
-    showFutureLoadingDialog(
-      context: context,
-      future: () => Matrix.of(context).client.login(
-            type: AuthenticationTypes.token,
-            token: token,
-            initialDeviceDisplayName: PlatformInfos.clientName,
-          ),
-    );
-  }
-
-  void _processIncomingUris(String text) async {
-    if (text == null || !text.startsWith(AppConfig.appOpenUrlScheme)) return;
-    VRouter.of(context).push('/home');
-    final token = Uri.parse(text).queryParameters['loginToken'];
-    if (token != null) _loginWithToken(token);
-  }
-
-  void _initReceiveUri() {
-    if (!PlatformInfos.isMobile) return;
-    // For receiving shared Uris
-    _intentDataStreamSubscription = linkStream.listen(_processIncomingUris);
-    if (FluffyChatApp.gotInitialLink == false) {
-      FluffyChatApp.gotInitialLink = true;
-      getInitialLink().then(_processIncomingUris);
-    }
-  }
-
-  @override
-  void initState() {
-    super.initState();
-    _initReceiveUri();
-    if (kIsWeb) {
-      WidgetsBinding.instance.addPostFrameCallback((_) {
-        final token =
-            Uri.parse(html.window.location.href).queryParameters['loginToken'];
-        _loginWithToken(token);
-      });
-    }
-  }
-
-  @override
-  void dispose() {
-    super.dispose();
-    _intentDataStreamSubscription?.cancel();
-  }
-
   bool get passwordLoginSupported =>
       Matrix.of(context)
           .client
@@ -118,7 +65,15 @@ class SignUpController extends State<SignUp> {
     return _rawLoginTypes;
   }
 
+  static const String _ssoHomeserverKey = 'sso-homeserver';
+
   void ssoLoginAction(String id) {
+    if (kIsWeb) {
+      // We store the homserver in the local storage instead of a redirect
+      // parameter because of possible CSRF attacks.
+      Store().setItem(
+          _ssoHomeserverKey, Matrix.of(context).client.homeserver.toString());
+    }
     final redirectUrl = kIsWeb
         ? html.window.location.href
         : AppConfig.appOpenUrlScheme.toLowerCase() + '://sso';