fix: secure whatsapp bridge with automatic local auth token

bridge/src/index.ts

@@ -25,7 +25,12 @@ import { join } from 'path';
 
 const PORT = parseInt(process.env.BRIDGE_PORT || '3001', 10);
 const AUTH_DIR = process.env.AUTH_DIR || join(homedir(), '.nanobot', 'whatsapp-auth');
-const TOKEN = process.env.BRIDGE_TOKEN || undefined;
+const TOKEN = process.env.BRIDGE_TOKEN?.trim();
+
+if (!TOKEN) {
+  console.error('BRIDGE_TOKEN is required. Start the bridge via nanobot so it can provision a local secret automatically.');
+  process.exit(1);
+}
 
 console.log('🐈 nanobot WhatsApp Bridge');
 console.log('========================\n');

bridge/src/server.ts

@@ -1,6 +1,6 @@
 /**
  * WebSocket server for Python-Node.js bridge communication.
- * Security: binds to 127.0.0.1 only; optional BRIDGE_TOKEN auth.
+ * Security: binds to 127.0.0.1 only; requires BRIDGE_TOKEN auth; rejects browser Origin headers.
  */
 
 import { WebSocketServer, WebSocket } from 'ws';
@@ -33,13 +33,29 @@ export class BridgeServer {
   private wa: WhatsAppClient | null = null;
   private clients: Set<WebSocket> = new Set();
 
-  constructor(private port: number, private authDir: string, private token?: string) {}
+  constructor(private port: number, private authDir: string, private token: string) {}
 
   async start(): Promise<void> {
+    if (!this.token.trim()) {
+      throw new Error('BRIDGE_TOKEN is required');
+    }
+
     // Bind to localhost only — never expose to external network
-    this.wss = new WebSocketServer({ host: '127.0.0.1', port: this.port });
+    this.wss = new WebSocketServer({
+      host: '127.0.0.1',
+      port: this.port,
+      verifyClient: (info, done) => {
+        const origin = info.origin || info.req.headers.origin;
+        if (origin) {
+          console.warn(`Rejected WebSocket connection with Origin header: ${origin}`);
+          done(false, 403, 'Browser-originated WebSocket connections are not allowed');
+          return;
+        }
+        done(true);
+      },
+    });
     console.log(`🌉 Bridge server listening on ws://127.0.0.1:${this.port}`);
-    if (this.token) console.log('🔒 Token authentication enabled');
+    console.log('🔒 Token authentication enabled');
 
     // Initialize WhatsApp client
     this.wa = new WhatsAppClient({
@@ -51,27 +67,22 @@ export class BridgeServer {
 
     // Handle WebSocket connections
     this.wss.on('connection', (ws) => {
-      if (this.token) {
-        // Require auth handshake as first message
-        const timeout = setTimeout(() => ws.close(4001, 'Auth timeout'), 5000);
-        ws.once('message', (data) => {
-          clearTimeout(timeout);
-          try {
-            const msg = JSON.parse(data.toString());
-            if (msg.type === 'auth' && msg.token === this.token) {
-              console.log('🔗 Python client authenticated');
-              this.setupClient(ws);
-            } else {
-              ws.close(4003, 'Invalid token');
-            }
-          } catch {
-            ws.close(4003, 'Invalid auth message');
+      // Require auth handshake as first message
+      const timeout = setTimeout(() => ws.close(4001, 'Auth timeout'), 5000);
+      ws.once('message', (data) => {
+        clearTimeout(timeout);
+        try {
+          const msg = JSON.parse(data.toString());
+          if (msg.type === 'auth' && msg.token === this.token) {
+            console.log('🔗 Python client authenticated');
+            this.setupClient(ws);
+          } else {
+            ws.close(4003, 'Invalid token');
           }
-        });
-      } else {
-        console.log('🔗 Python client connected');
-        this.setupClient(ws);
-      }
+        } catch {
+          ws.close(4003, 'Invalid auth message');
+        }
+      });
     });
 
     // Connect to WhatsApp