add bind for relay

pkg/handler/socks/v5/udp.go

@@ -2,7 +2,6 @@ package v5
 
 import (
 	"context"
-	"errors"
 	"fmt"
 	"io"
 	"io/ioutil"
@@ -10,7 +9,6 @@ import (
 	"time"
 
 	"github.com/go-gost/gosocks5"
-	"github.com/go-gost/gost/pkg/chain"
 	"github.com/go-gost/gost/pkg/common/bufpool"
 	"github.com/go-gost/gost/pkg/common/util/socks"
 )
@@ -54,153 +52,24 @@ func (h *socks5Handler) handleUDP(ctx context.Context, conn net.Conn) {
 	})
 	h.logger.Debugf("bind on %s OK", relay.LocalAddr())
 
-	if h.chain.IsEmpty() {
-		// serve as standard socks5 udp relay.
-		peer, err := net.ListenUDP("udp", nil)
-		if err != nil {
-			h.logger.Error(err)
-			return
-		}
-		defer peer.Close()
-
-		go h.relayUDP(
-			socks.UDPConn(relay, h.md.udpBufferSize),
-			peer,
-		)
-	} else {
-		tun, err := h.getUDPTun(ctx)
-		if err != nil {
-			h.logger.Error(err)
-			return
-		}
-		defer tun.Close()
-
-		go h.tunnelClientUDP(
-			socks.UDPConn(relay, h.md.udpBufferSize),
-			socks.UDPTunClientPacketConn(tun),
-		)
+	peer, err := net.ListenUDP("udp", nil)
+	if err != nil {
+		h.logger.Error(err)
+		return
 	}
+	defer peer.Close()
+
+	go h.relayUDP(
+		socks.UDPConn(relay, h.md.udpBufferSize),
+		peer,
+	)
 
 	t := time.Now()
-	h.logger.Infof("%s <-> %s", conn.RemoteAddr(), &saddr)
+	h.logger.Infof("%s <-> %s", conn.RemoteAddr(), relay.LocalAddr())
 	io.Copy(ioutil.Discard, conn)
 	h.logger.
 		WithFields(map[string]interface{}{"duration": time.Since(t)}).
-		Infof("%s >-< %s", conn.RemoteAddr(), &saddr)
-}
-
-func (h *socks5Handler) getUDPTun(ctx context.Context) (conn net.Conn, err error) {
-	r := (&chain.Router{}).
-		WithChain(h.chain).
-		WithRetry(h.md.retryCount).
-		WithLogger(h.logger)
-	conn, err = r.Connect(ctx)
-	if err != nil {
-		return nil, err
-	}
-
-	defer func() {
-		if err != nil {
-			conn.Close()
-			conn = nil
-		}
-	}()
-
-	if h.md.timeout > 0 {
-		conn.SetDeadline(time.Now().Add(h.md.timeout))
-		defer conn.SetDeadline(time.Time{})
-	}
-
-	req := gosocks5.NewRequest(socks.CmdUDPTun, nil)
-	if err = req.Write(conn); err != nil {
-		return
-	}
-	h.logger.Debug(req)
-
-	reply, err := gosocks5.ReadReply(conn)
-	if err != nil {
-		return
-	}
-	h.logger.Debug(reply)
-
-	if reply.Rep != gosocks5.Succeeded {
-		err = errors.New("UDP associate failed")
-		return
-	}
-
-	return
-}
-
-func (h *socks5Handler) tunnelClientUDP(c, tun net.PacketConn) (err error) {
-	bufSize := h.md.udpBufferSize
-	errc := make(chan error, 2)
-
-	go func() {
-		for {
-			err := func() error {
-				b := bufpool.Get(bufSize)
-				defer bufpool.Put(b)
-
-				n, raddr, err := c.ReadFrom(b)
-				if err != nil {
-					return err
-				}
-
-				if h.bypass != nil && h.bypass.Contains(raddr.String()) {
-					h.logger.Warn("bypass: ", raddr)
-					return nil
-				}
-
-				if _, err := tun.WriteTo(b[:n], raddr); err != nil {
-					return err
-				}
-
-				h.logger.Debugf("%s >>> %s data: %d",
-					tun.LocalAddr(), raddr, n)
-
-				return nil
-			}()
-
-			if err != nil {
-				errc <- err
-				return
-			}
-		}
-	}()
-
-	go func() {
-		for {
-			err := func() error {
-				b := bufpool.Get(bufSize)
-				defer bufpool.Put(b)
-
-				n, raddr, err := tun.ReadFrom(b)
-				if err != nil {
-					return err
-				}
-				if h.bypass != nil && h.bypass.Contains(raddr.String()) {
-					h.logger.Warn("bypass: ", raddr)
-					return nil
-				}
-
-				if _, err := c.WriteTo(b[:n], raddr); err != nil {
-					return err
-				}
-
-				h.logger.Debugf("%s <<< %s data: %d",
-					tun.LocalAddr(), raddr, n)
-
-				return nil
-			}()
-
-			if err != nil {
-				errc <- err
-				return
-			}
-		}
-	}()
-
-	return <-errc
+		Infof("%s >-< %s", conn.RemoteAddr(), relay.LocalAddr())
 }
 
 func (h *socks5Handler) relayUDP(c, peer net.PacketConn) (err error) {