calling: add setTurnServerOverride to SignalDebug to allow choosing ice server

Co-authored-by: Adel Lahlou <adel@signal.com>

ts/services/calling.ts

@@ -156,6 +156,8 @@ const RINGRTC_HTTP_METHOD_TO_OUR_HTTP_METHOD: Map<
 
 const CLEAN_EXPIRED_GROUP_CALL_RINGS_INTERVAL = 10 * durations.MINUTE;
 
+const ICE_SERVER_IS_IP_LIKE = /(turn|turns|stun):[.\d]+/;
+
 // We send group call update messages to tell other clients to peek, which triggers
 //   notifications, timeline messages, big green "Join" buttons, and so on. This enum
 //   represents the three possible states we can be in. This helps ensure that we don't
@@ -315,6 +317,8 @@ export class CallingClass {
 
   public _sfuUrl?: string;
 
+  public _iceServerOverride?: string;
+
   private lastMediaDeviceSettings?: MediaDeviceSettings;
 
   private deviceReselectionTimer?: NodeJS.Timeout;
@@ -2598,23 +2602,36 @@ export class CallingClass {
     // If the peer is not in the user's system contacts, force IP hiding.
     const isContactUntrusted = !isInSystemContacts(conversation.attributes);
 
+    // only include hostname with urlsWithIps
+    const iceServers = this._iceServerOverride
+      ? [
+          {
+            hostname: ICE_SERVER_IS_IP_LIKE.test(this._iceServerOverride)
+              ? iceServer.hostname
+              : '',
+            username: iceServer.username,
+            password: iceServer.password,
+            urls: [this._iceServerOverride.toString()],
+          },
+        ]
+      : // proritize ice servers with IPs to avoid DNS
+        [
+          {
+            hostname: iceServer.hostname,
+            username: iceServer.username,
+            password: iceServer.password,
+            urls: (iceServer.urlsWithIps ?? []).slice(),
+          },
+          {
+            hostname: '',
+            username: iceServer.username,
+            password: iceServer.password,
+            urls: (iceServer.urls ?? []).slice(),
+          },
+        ];
+
     const callSettings = {
-      // only include hostname with urlsWithIps
-      // proritize ice servers with IPs to avoid DNS
-      iceServers: [
-        {
-          hostname: iceServer.hostname,
-          username: iceServer.username,
-          password: iceServer.password,
-          urls: (iceServer.urlsWithIps ?? []).slice(),
-        },
-        {
-          hostname: '',
-          username: iceServer.username,
-          password: iceServer.password,
-          urls: (iceServer.urls ?? []).slice(),
-        },
-      ],
+      iceServers,
       hideIp: shouldRelayCalls || isContactUntrusted,
       dataMode: DataMode.Normal,
       // TODO: DESKTOP-3101

ts/window.d.ts

@@ -195,6 +195,7 @@ declare global {
     getServerPublicParams: () => string;
     getGenericServerPublicParams: () => string;
     getSfuUrl: () => string;
+    getIceServerOverride: () => string;
     getSocketStatus: () => SocketStatus;
     getSyncRequest: (timeoutMillis?: number) => SyncRequest;
     getTitle: () => string;

ts/windows/main/start.ts

@@ -55,6 +55,8 @@ if (!isProduction(window.SignalContext.getVersion())) {
       window.MessageCache.__DEPRECATED$getById(id),
     getReduxState: () => window.reduxStore.getState(),
     getSfuUrl: () => window.Signal.Services.calling._sfuUrl,
+    getIceServerOverride: () =>
+      window.Signal.Services.calling._iceServerOverride,
     getStorageItem: (name: keyof StorageAccessType) => window.storage.get(name),
     putStorageItem: <K extends keyof StorageAccessType>(
       name: K,
@@ -69,6 +71,14 @@ if (!isProduction(window.SignalContext.getVersion())) {
     setSfuUrl: (url: string) => {
       window.Signal.Services.calling._sfuUrl = url;
     },
+    setIceServerOverride: (url: string) => {
+      if (!/(turn|turns|stun):.*]/.test(url)) {
+        log.warn(
+          'Override url should be prefixed with `turn:`, `turns:`, or `stun:` else override may not work'
+        );
+      }
+      window.Signal.Services.calling._iceServerOverride = url;
+    },
     sqlCall: (name: string, ...args: ReadonlyArray<unknown>) =>
       ipcInvoke(name, args),
     ...(window.SignalContext.config.ciMode === 'benchmark'