refactor: move auth token from cookies to Sec-WebSocket-Protocol header

This change improves security by:
1. Moving auth token from cookies to Sec-WebSocket-Protocol header
2. Using standard WebSocket protocol features for auth
3. Removing token exposure in URLs
4. Only transmitting token during initial handshake

frontend/src/context/socket.tsx

@@ -50,7 +50,8 @@ function SocketProvider({ children }: SocketProviderProps) {
     const baseUrl = import.meta.env.VITE_BACKEND_BASE_URL || fallback;
     const protocol = window.location.protocol === "https:" ? "wss:" : "ws:";
     const ws = new WebSocket(
-      `${protocol}//${baseUrl}/ws${options?.token ? `?token=${options.token}` : ""}`,
+      `${protocol}//${baseUrl}/ws`,
+      ["openhands", options?.token || ""] // First protocol is our real protocol, second is the auth token
     );
 
     ws.addEventListener("open", (event) => {

openhands/server/listen.py

@@ -302,34 +302,36 @@ async def websocket_endpoint(websocket: WebSocket):
         {"action": "finish", "args": {}}
         ```
     """
-    cookies = dict(
-        cookie.split('=')
-        for cookie in websocket.headers.get('cookie', '').split('; ')
-        if cookie
-    )
-    auth_cookie = cookies.get('openhands_auth')
-
-    if not await authenticate_github_user(auth_cookie):
+    # Get protocols from Sec-WebSocket-Protocol header
+    protocols = websocket.headers.get('sec-websocket-protocol', '').split(', ')
+
+    # The first protocol should be our real protocol (e.g. 'openhands')
+    # The second protocol should contain our auth token
+    if len(protocols) < 2:
         await websocket.close(code=status.WS_1008_POLICY_VIOLATION)
         return
 
-    await asyncio.wait_for(websocket.accept(), 10)
+    real_protocol = protocols[0]
+    auth_token = protocols[1]
+
+    # Verify GitHub authentication
+    if not await authenticate_github_user(auth_token):
+        await websocket.close(code=status.WS_1008_POLICY_VIOLATION)
+        return
 
-    if websocket.query_params.get('token'):
-        token = websocket.query_params.get('token')
-        sid = get_sid_from_token(token, config.jwt_secret)
+    # Accept the connection with the real protocol
+    await asyncio.wait_for(websocket.accept(subprotocol=real_protocol), 10)
 
-        if sid == '':
-            await websocket.send_json({'error': 'Invalid token', 'error_code': 401})
-            await websocket.close()
-            return
-    else:
-        sid = str(uuid.uuid4())
-        token = sign_token({'sid': sid}, config.jwt_secret)
+    # Extract session ID from token
+    sid = get_sid_from_token(auth_token, config.jwt_secret)
+    if sid == '':
+        await websocket.send_json({'error': 'Invalid token', 'error_code': 401})
+        await websocket.close()
+        return
 
     logger.info(f'New session: {sid}')
     session = session_manager.add_or_restart_session(sid, websocket)
-    await websocket.send_json({'token': token, 'status': 'ok'})
+    await websocket.send_json({'token': auth_token, 'status': 'ok'})
 
     latest_event_id = -1
     if websocket.query_params.get('latest_event_id'):