Fix (rust crypto): Adjust login procedures to account for rust crypto behaviour. (#2603)

* Fix for missing client store (caused by: #2587)

* Fix interactive login with authenticated guest user.
Fix clearing storage before logging in a new account.

src/ClientContext.tsx

@@ -379,19 +379,15 @@ async function loadClient(): Promise<InitResult | null> {
       } catch (err) {
         if (err instanceof MatrixError && err.errcode === "M_UNKNOWN_TOKEN") {
           // We can't use this session anymore, so let's log it out
-          try {
-            const client = await initClient(initClientParams, false); // Don't need the crypto store just to log out)
-            await client.logout(true);
-          } catch (err) {
-            logger.warn(
-              "The previous session was unable to login, and we couldn't log it out: " +
-                err,
+          logger.log(
+            "The session from local store is invalid; continuing without a client",
           );
-          }
+          clearSession();
+          // returning null = "no client` pls register" (undefined = "loading" which is the current value when reaching this line)
+          return null;
         }
         throw err;
       }
-      /* eslint-enable camelcase */
     } catch (err) {
       clearSession();
       throw err;

src/auth/LoginPage.tsx

@@ -32,8 +32,8 @@ export const LoginPage: FC = () => {
   const { t } = useTranslation();
   usePageTitle(t("login_title"));
 
-  const { setClient } = useClient();
-  const login = useInteractiveLogin();
+  const { client, setClient } = useClient();
+  const login = useInteractiveLogin(client);
   const homeserver = Config.defaultHomeserverUrl(); // TODO: Make this configurable
   const usernameRef = useRef<HTMLInputElement>(null);
   const passwordRef = useRef<HTMLInputElement>(null);

src/auth/useInteractiveLogin.ts

@@ -24,8 +24,15 @@ import {
 
 import { initClient } from "../utils/matrix";
 import { Session } from "../ClientContext";
-
-export function useInteractiveLogin(): (
+/**
+ * This provides the login method to login using user credentials.
+ * @param oldClient If there is an already authenticated client it should be passed to this hook
+ * this allows the interactive login to sign out the client before logging in.
+ * @returns A async method that can be called/awaited to log in with the provided credentials.
+ */
+export function useInteractiveLogin(
+  oldClient?: MatrixClient,
+): (
   homeserver: string,
   username: string,
   password: string,
@@ -36,7 +43,8 @@ export function useInteractiveLogin(): (
       username: string,
       password: string,
     ) => Promise<[MatrixClient, Session]>
-  >(async (homeserver: string, username: string, password: string) => {
+  >(
+    async (homeserver: string, username: string, password: string) => {
       const authClient = createClient({ baseUrl: homeserver });
 
       const interactiveAuth = new InteractiveAuth({
@@ -67,6 +75,8 @@ export function useInteractiveLogin(): (
         passwordlessUser: false,
       };
 
+      // To not confuse the rust crypto sessions we need to logout the old client before initializing the new one.
+      await oldClient?.logout(true);
       const client = await initClient(
         {
           baseUrl: homeserver,
@@ -78,5 +88,7 @@ export function useInteractiveLogin(): (
       );
       /* eslint-enable camelcase */
       return [client, session];
-  }, []);
+    },
+    [oldClient],
+  );
 }

src/utils/matrix.ts

@@ -71,10 +71,12 @@ async function waitForSync(client: MatrixClient): Promise<void> {
 
 /**
  * Initialises and returns a new standalone Matrix Client.
- * If false is passed for the 'restore' parameter, corresponding crypto
- * data is cleared before the client initialization.
+ * This can only be called safely if no other client is running
+ * otherwise rust crypto will throw since it is not ready to initialize a new session.
+ * If another client is running make sure `.logout()` is called before executing this function.
  * @param clientOptions Object of options passed through to the client
- * @param restore Whether the session is being restored from storage
+ * @param restore If the rust crypto should be reset before the cient initialization or
+ * if the initialization should try to restore the crypto state from the indexDB.
  * @returns The MatrixClient instance
  */
 export async function initClient(
@@ -130,20 +132,17 @@ export async function initClient(
     fallbackICEServerAllowed: fallbackICEServerAllowed,
   });
 
-  // In case of registering a new matrix account caused by broken store state. This is particularly needed for:
+  // In case of logging in a new matrix account but there is still crypto local store. This is needed for:
   // - We lost the auth tokens and cannot restore the client resulting in registering a new user.
-  // - Need to make sure any possible leftover crypto store gets cleared.
+  // - We start the sign in flow but are registered with a guest user. (It should additionally log out the guest before)
   // - A new account is created because of missing LocalStorage: "matrix-auth-store", but the crypto IndexDB is still available.
-  //   This would result in conflicting crypto store userId vs matrixClient userId. Caused by EC 0.6.1
   if (!restore) {
-    client.clearStores();
+    await client.clearStores();
   }
 
   // Start client store.
   // Note: The `client.store` is used to store things like sync results. It's independent of
   // the cryptostore, and uses a separate indexeddb database.
-
-  // start the client store (totally independent to the crypto store)
   try {
     await client.store.startup();
   } catch (error) {
@@ -156,7 +155,14 @@ export async function initClient(
   }
 
   // Also creates and starts any crypto related stores.
+  try {
     await client.initRustCrypto();
+  } catch (err) {
+    logger.warn(
+      err,
+      "Make sure to clear client stores before initializing the rust crypto.",
+    );
+  }
 
   client.setGlobalErrorOnUnknownDevices(false);
   // Once startClient is called, syncs are run asynchronously.