Do not allow joining a call without E2EE key

Signed-off-by: Šimon Brandner <simon.bra.ag@gmail.com>

src/e2ee/sharedKeyManagement.ts

@@ -14,13 +14,12 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
-import { useEffect, useMemo } from "react";
-import { randomString } from "matrix-js-sdk/src/randomstring";
+import { useMemo } from "react";
 
 import { useEnableE2EE } from "../settings/useSetting";
 import { useLocalStorage } from "../useLocalStorage";
 
-const getRoomSharedKeyLocalStorageKey = (roomId: string): string =>
+export const getRoomSharedKeyLocalStorageKey = (roomId: string): string =>
   `room-shared-key-${roomId}`;
 
 export const useRoomSharedKey = (
@@ -30,11 +29,5 @@ export const useRoomSharedKey = (
   const [e2eeEnabled] = useEnableE2EE();
   const [roomSharedKey, setRoomSharedKey] = useLocalStorage(key);
 
-  useEffect(() => {
-    if ((roomSharedKey && roomSharedKey !== "") || !e2eeEnabled) return;
-
-    setRoomSharedKey(randomString(32));
-  }, [roomSharedKey, e2eeEnabled, setRoomSharedKey]);
-
   return e2eeEnabled ? [roomSharedKey, setRoomSharedKey] : [null, null];
 };

src/home/RegisteredView.tsx

@@ -17,6 +17,7 @@ limitations under the License.
 import { useState, useCallback, FormEvent, FormEventHandler } from "react";
 import { useHistory } from "react-router-dom";
 import { MatrixClient } from "matrix-js-sdk/src/client";
+import { randomString } from "matrix-js-sdk/src/randomstring";
 import { useTranslation } from "react-i18next";
 
 import {
@@ -40,6 +41,8 @@ import { CallType, CallTypeDropdown } from "./CallTypeDropdown";
 import { useOptInAnalytics } from "../settings/useSetting";
 import { AnalyticsNotice } from "../analytics/AnalyticsNotice";
 import { E2EEBanner } from "../E2EEBanner";
+import { setLocalStorageItem } from "../useLocalStorage";
+import { getRoomSharedKeyLocalStorageKey } from "../e2ee/sharedKeyManagement";
 
 interface Props {
   client: MatrixClient;
@@ -70,12 +73,15 @@ export function RegisteredView({ client, isPasswordlessUser }: Props) {
         setError(undefined);
         setLoading(true);
 
-        const [roomAlias] = await createRoom(client, roomName, ptt);
+        const [roomAlias, roomId] = await createRoom(client, roomName, ptt);
+
+        setLocalStorageItem(
+          getRoomSharedKeyLocalStorageKey(roomId),
+          randomString(32)
+        );
 
-        if (roomAlias) {
         history.push(`/${roomAlias.substring(1).split(":")[0]}`);
       }
-      }
 
       submit().catch((error) => {
         if (error.errcode === "M_ROOM_IN_USE") {

src/room/GroupCallView.tsx

@@ -40,6 +40,7 @@ import { MuteStates, useMuteStates } from "./MuteStates";
 import { useMediaDevices, MediaDevices } from "../livekit/MediaDevicesContext";
 import { useRoomSharedKey } from "../e2ee/sharedKeyManagement";
 import { PASSWORD_STRING, useUrlParams } from "../UrlParams";
+import { useEnableE2EE } from "../settings/useSetting";
 
 declare global {
   interface Window {
@@ -244,6 +245,7 @@ export function GroupCallView({
     }
   }, [groupCall, state, leave]);
 
+  const [e2eeEnabled] = useEnableE2EE();
   const [e2eeSharedKey, setE2EESharedKey] = useRoomSharedKey(
     groupCall.room.roomId
   );
@@ -275,6 +277,18 @@ export function GroupCallView({
     groupCall.enter();
   }, [groupCall]);
 
+  if (!password && !e2eeSharedKey && e2eeEnabled) {
+    return (
+      <ErrorView
+        error={
+          new Error(
+            "No E2EE key provided: please make sure the URL you're using to join this call has been retrieved using the in-app button."
+          )
+        }
+      />
+    );
+  }
+
   const livekitServiceURL =
     groupCall.livekitServiceURL ?? Config.get().livekit?.livekit_service_url;
   if (!livekitServiceURL) {