Ejemplo n.º 1
0
func (r *relayHandler) ServeSocks(conn *gosocks.SocksConn) {
	conn.SetReadDeadline(time.Now().Add(conn.Timeout))
	req, err := gosocks.ReadSocksRequest(conn)
	if err != nil {
		log.Printf("error in ReadSocksRequest: %s", err)
		return
	}

	switch req.Cmd {
	case gosocks.SocksCmdConnect:
		chain := r.lookup(req.DstHost, conn)
		if chain != nil {
			chain.TCP(req, conn)
		} else {
			r.basic.HandleCmdConnect(req, conn)
		}
		return
	case gosocks.SocksCmdUDPAssociate:
		r.handleUDPAssociate(req, conn)
		return
	case gosocks.SocksCmdBind:
		conn.Close()
		return
	default:
		return
	}
}
Ejemplo n.º 2
0
func (srv *server) transactBegin(s *session, w http.ResponseWriter, req *http.Request) error {
	body := http.MaxBytesReader(w, req.Body, maxPayloadLength+1)
	dialer := &gosocks.SocksDialer{
		Timeout: socksTimeout,
		Auth:    &gosocks.AnonymousClientAuthenticator{},
	}
	conn, err := dialer.Dial(srv.socksAddr)
	if err != nil {
		meekResponse(w, "Internal server error", []byte(""))
		return err
	}
	// I am sure that this is a TCPConn
	conn.Conn.(*net.TCPConn).SetReadBuffer(socksReadBufSize)
	s.tc = conn

	socksReq, err := gosocks.ReadSocksRequest(body)
	if socksReq.Cmd == gosocks.SocksCmdUDPAssociate {
		// if cmd is UDP_ASSOCIATE, no restriction on sending address
		socksReq.HostType = gosocks.SocksIPv4Host
		socksReq.DstHost = "0.0.0.0"
		socksReq.DstPort = 0
	}

	if err != nil {
		meekResponse(w, "Bad request", []byte(""))
		return fmt.Errorf("invalid socks request: %s", err)
	}
	socksReply, err := gosocks.ClientRequest(s.tc, socksReq)
	if err != nil || socksReply.Rep != gosocks.SocksSucceeded {
		meekResponse(w, "Internal server error", []byte(""))
		return err
	}

	log.Printf("[%s] cmd 0x%02x with DstAddr: %s:%d", s.remoteAddr, socksReq.Cmd, socksReq.DstHost, socksReq.DstPort)
	if socksReq.Cmd == gosocks.SocksCmdUDPAssociate {
		uc, err := net.Dial("udp", gosocks.SockAddrString(socksReply.BndHost, socksReply.BndPort))
		if err != nil {
			meekResponse(w, "Internal server error", []byte(""))
			return err
		}
		s.uc = uc.(*net.UDPConn)
		s.uc.SetReadBuffer(socksReadBufSize)
	}

	gosocks.WriteSocksReply(w, socksReply)
	return nil
}