Method handleAssociate

pkg/socks5/server.go:295–341

(req *request)

}

func (s *Server) handleAssociate(req *request) error {
	destinationAddr := req.DestinationAddr.String()
	udpConn, err := s.ProxyListenPacket(s.Context, "udp", destinationAddr)
	if err != nil {
		if err := sendReply(req.Conn, errToReply(err), nil); err != nil {
			return fmt.Errorf("failed to send reply: %v", err)
		}
		return fmt.Errorf("connect to %v failed: %w", req.DestinationAddr, err)
	}

	ip, port, err := s.PacketForwardAddress(s.Context, destinationAddr, udpConn, req.Conn)
	if err != nil {
		return err
	}
	bind := address{IP: ip, Port: port}
	if err := sendReply(req.Conn, successReply, &bind); err != nil {
		return fmt.Errorf("failed to send reply: %v", err)
	}

	if s.UserAssociateHandle == nil {
		return s.embedHandleAssociate(req, udpConn)
	}

	cConn := &udpCustomConn{
		PacketConn:   udpConn,
		assocTCPConn: req.Conn,
		frc:          make(chan bool),
		packetQueue:  make(chan *readStruct),
	}

	cConn.asyncReadPackets()

	// wait for first packet so that target sender and receiver get known
	<-cConn.frc

	proxyReq := &statute.ProxyRequest{
		Conn:        cConn,
		Reader:      cConn,
		Writer:      cConn,
		Network:     "udp",
		Destination: cConn.targetAddr.String(),
		DestHost:    cConn.targetAddr.(*net.UDPAddr).IP.String(),
		DestPort:    int32(cConn.targetAddr.(*net.UDPAddr).Port),
	}

	return s.UserAssociateHandle(proxyReq)
}

func (s *Server) embedHandleAssociate(req *request, udpConn net.PacketConn) error {
	defer func() {