From 4d52c9f5d2af0f008cc626daeaef7ecbda41e4f8 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Rados=C5=82aw=20Gierwia=C5=82o?= <github@radziel.com>
Date: Sat, 15 Nov 2025 19:00:24 +0100
Subject: [PATCH] feat: add TURN servers for symmetric NAT traversal

- Add openrelay.metered.ca TURN servers for testing
- Support connections through symmetric NAT (mobile networks)
- Add TCP transport fallback for strict firewalls
- Enables P2P file transfer across different networks
---
 frontend/src/hooks/useWebRTC.js | 20 +++++++++++++++++++-
 1 file changed, 19 insertions(+), 1 deletion(-)

diff --git a/frontend/src/hooks/useWebRTC.js b/frontend/src/hooks/useWebRTC.js
index 618679b..5c25a75 100644
--- a/frontend/src/hooks/useWebRTC.js
+++ b/frontend/src/hooks/useWebRTC.js
@@ -1,12 +1,30 @@
 import { useState, useEffect, useRef, useCallback } from 'react';
 import { getSocket } from '../services/socket';
 
-// WebRTC configuration with STUN servers for NAT traversal
+// WebRTC configuration with STUN and TURN servers for NAT traversal
 const rtcConfig = {
   iceServers: [
+    // STUN servers for basic NAT traversal
     { urls: 'stun:stun.l.google.com:19302' },
     { urls: 'stun:stun1.l.google.com:19302' },
     { urls: 'stun:stun2.l.google.com:19302' },
+
+    // TURN servers for symmetric NAT and strict firewalls (public relay for testing)
+    {
+      urls: 'turn:openrelay.metered.ca:80',
+      username: 'openrelayproject',
+      credential: 'openrelayproject',
+    },
+    {
+      urls: 'turn:openrelay.metered.ca:443',
+      username: 'openrelayproject',
+      credential: 'openrelayproject',
+    },
+    {
+      urls: 'turn:openrelay.metered.ca:443?transport=tcp',
+      username: 'openrelayproject',
+      credential: 'openrelayproject',
+    },
   ],
 };