Use the TcpListenter and UdpConn from the remote

go/chisel/share/tunnel/tunnel_in_proxy.go

@@ -50,16 +50,21 @@ func (p *Proxy) listen() error {
 	if p.remote.Stdio {
 		//TODO check if pipes active?
 	} else if p.remote.LocalProto == "tcp" {
-		addr, err := net.ResolveTCPAddr("tcp", p.remote.LocalHost+":"+p.remote.LocalPort)
-		if err != nil {
-			return p.Errorf("resolve: %s", err)
-		}
-		l, err := net.ListenTCP("tcp", addr)
-		if err != nil {
-			return p.Errorf("tcp: %s", err)
+		if p.remote.ReusedTcpListener != nil {
+			p.tcp = p.remote.ReusedTcpListener
+			p.remote.ReusedTcpListener = nil
+		} else {
+			addr, err := net.ResolveTCPAddr("tcp", p.remote.LocalHost+":"+p.remote.LocalPort)
+			if err != nil {
+				return p.Errorf("resolve: %s", err)
+			}
+			l, err := net.ListenTCP("tcp", addr)
+			if err != nil {
+				return p.Errorf("tcp: %s", err)
+			}
+			p.Infof("Listening")
+			p.tcp = l
 		}
-		p.Infof("Listening")
-		p.tcp = l
 	} else if p.remote.LocalProto == "udp" {
 		l, err := listenUDP(p.Logger, p.sshTun, p.remote)
 		if err != nil {

go/chisel/share/tunnel/tunnel_in_proxy_udp.go

@@ -32,13 +32,19 @@ import (
 // of time, so that when the exit node receives a response on 6345, it
 // knows to return it to 1111.
 func listenUDP(l *cio.Logger, sshTun sshTunnel, remote *settings.Remote) (*udpListener, error) {
-	a, err := net.ResolveUDPAddr("udp", remote.Local())
-	if err != nil {
-		return nil, l.Errorf("resolve: %s", err)
-	}
-	conn, err := net.ListenUDP("udp", a)
-	if err != nil {
-		return nil, l.Errorf("listen: %s", err)
+	var conn *net.UDPConn
+	if remote.ReusedUdpConn != nil {
+		conn = remote.ReusedUdpConn
+		remote.ReusedUdpConn = nil
+	} else {
+		a, err := net.ResolveUDPAddr("udp", remote.Local())
+		if err != nil {
+			return nil, l.Errorf("resolve: %s", err)
+		}
+		conn, err = net.ListenUDP("udp", a)
+		if err != nil {
+			return nil, l.Errorf("listen: %s", err)
+		}
 	}
 	//ready
 	u := &udpListener{