feat(smart-proxy): add UDP transport support with QUIC/HTTP3 routing and datagram handler relay

ts/proxies/smart-proxy/smart-proxy.ts

@@ -5,6 +5,7 @@ import { logger } from '../../core/utils/logger.js';
 import { RustProxyBridge } from './rust-proxy-bridge.js';
 import { RoutePreprocessor } from './route-preprocessor.js';
 import { SocketHandlerServer } from './socket-handler-server.js';
+import { DatagramHandlerServer } from './datagram-handler-server.js';
 import { RustMetricsAdapter } from './rust-metrics-adapter.js';
 
 // Route management
@@ -36,6 +37,7 @@ export class SmartProxy extends plugins.EventEmitter {
   private bridge: RustProxyBridge;
   private preprocessor: RoutePreprocessor;
   private socketHandlerServer: SocketHandlerServer | null = null;
+  private datagramHandlerServer: DatagramHandlerServer | null = null;
   private metricsAdapter: RustMetricsAdapter;
   private routeUpdateLock: Mutex;
   private stopping = false;
@@ -145,6 +147,16 @@ export class SmartProxy extends plugins.EventEmitter {
       await this.socketHandlerServer.start();
     }
 
+    // Check if any routes need datagram handler relay (UDP socket-handler routes)
+    const hasDatagramHandlers = this.settings.routes.some(
+      (r) => r.action.type === 'socket-handler' && r.action.datagramHandler
+    );
+    if (hasDatagramHandlers) {
+      const dgPath = `/tmp/smartproxy-dgram-relay-${process.pid}.sock`;
+      this.datagramHandlerServer = new DatagramHandlerServer(dgPath, this.preprocessor);
+      await this.datagramHandlerServer.start();
+    }
+
     // Preprocess routes (strip JS functions, convert socket-handler routes)
     const rustRoutes = this.preprocessor.preprocessForRust(this.settings.routes);
 
@@ -167,6 +179,11 @@ export class SmartProxy extends plugins.EventEmitter {
       await this.bridge.setSocketHandlerRelay(this.socketHandlerServer.getSocketPath());
     }
 
+    // Configure datagram handler relay
+    if (this.datagramHandlerServer) {
+      await this.bridge.setDatagramHandlerRelay(this.datagramHandlerServer.getSocketPath());
+    }
+
     // Load default self-signed fallback certificate (domain: '*')
     if (!this.settings.disableDefaultCert) {
       try {
@@ -240,6 +257,12 @@ export class SmartProxy extends plugins.EventEmitter {
       this.socketHandlerServer = null;
     }
 
+    // Stop datagram handler relay
+    if (this.datagramHandlerServer) {
+      await this.datagramHandlerServer.stop();
+      this.datagramHandlerServer = null;
+    }
+
     logger.log('info', 'SmartProxy shutdown complete.', { component: 'smart-proxy' });
   }