gost/pkg/handler/socks/v5/udp.go
2022-03-14 17:43:37 +08:00

86 lines
1.9 KiB
Go

package v5
import (
"context"
"errors"
"fmt"
"io"
"io/ioutil"
"net"
"time"
"github.com/go-gost/gosocks5"
"github.com/go-gost/gost/v3/pkg/common/net/relay"
"github.com/go-gost/gost/v3/pkg/internal/util/socks"
"github.com/go-gost/gost/v3/pkg/logger"
)
func (h *socks5Handler) handleUDP(ctx context.Context, conn net.Conn, log logger.Logger) error {
log = log.WithFields(map[string]any{
"cmd": "udp",
})
if !h.md.enableUDP {
reply := gosocks5.NewReply(gosocks5.NotAllowed, nil)
log.Debug(reply)
log.Error("socks5: UDP relay is disabled")
return reply.Write(conn)
}
cc, err := net.ListenUDP("udp", nil)
if err != nil {
log.Error(err)
reply := gosocks5.NewReply(gosocks5.Failure, nil)
reply.Write(conn)
log.Debug(reply)
return err
}
defer cc.Close()
saddr := gosocks5.Addr{}
saddr.ParseFrom(cc.LocalAddr().String())
saddr.Type = 0
saddr.Host, _, _ = net.SplitHostPort(conn.LocalAddr().String()) // replace the IP to the out-going interface's
reply := gosocks5.NewReply(gosocks5.Succeeded, &saddr)
if err := reply.Write(conn); err != nil {
log.Error(err)
return err
}
log.Debug(reply)
log = log.WithFields(map[string]any{
"bind": fmt.Sprintf("%s/%s", cc.LocalAddr(), cc.LocalAddr().Network()),
})
log.Debugf("bind on %s OK", cc.LocalAddr())
// obtain a udp connection
c, err := h.router.Dial(ctx, "udp", "") // UDP association
if err != nil {
log.Error(err)
return err
}
defer c.Close()
pc, ok := c.(net.PacketConn)
if !ok {
err := errors.New("socks5: wrong connection type")
log.Error(err)
return err
}
r := relay.NewUDPRelay(socks.UDPConn(cc, h.md.udpBufferSize), pc).
WithBypass(h.options.Bypass).
WithLogger(log)
r.SetBufferSize(h.md.udpBufferSize)
go r.Run()
t := time.Now()
log.Infof("%s <-> %s", conn.RemoteAddr(), cc.LocalAddr())
io.Copy(ioutil.Discard, conn)
log.WithFields(map[string]any{"duration": time.Since(t)}).
Infof("%s >-< %s", conn.RemoteAddr(), cc.LocalAddr())
return nil
}