x/handler/socks/v5/bind.go
2024-06-24 21:18:04 +08:00

154 lines
3.3 KiB
Go

package v5
import (
"context"
"fmt"
"net"
"time"
"github.com/go-gost/core/logger"
"github.com/go-gost/gosocks5"
netpkg "github.com/go-gost/x/internal/net"
xnet "github.com/go-gost/x/internal/net"
)
func (h *socks5Handler) handleBind(ctx context.Context, conn net.Conn, network, address string, log logger.Logger) error {
log = log.WithFields(map[string]any{
"dst": fmt.Sprintf("%s/%s", address, network),
"cmd": "bind",
})
log.Debugf("%s >> %s", conn.RemoteAddr(), address)
if !h.md.enableBind {
reply := gosocks5.NewReply(gosocks5.NotAllowed, nil)
log.Trace(reply)
log.Error("socks5: BIND is disabled")
return reply.Write(conn)
}
// BIND does not support chain.
return h.bindLocal(ctx, conn, network, address, log)
}
func (h *socks5Handler) bindLocal(ctx context.Context, conn net.Conn, network, address string, log logger.Logger) error {
lc := xnet.ListenConfig{
Netns: h.options.Netns,
}
ln, err := lc.Listen(ctx, network, address) // strict mode: if the port already in use, it will return error
if err != nil {
log.Error(err)
reply := gosocks5.NewReply(gosocks5.Failure, nil)
if err := reply.Write(conn); err != nil {
log.Error(err)
}
log.Debug(reply)
return err
}
socksAddr := gosocks5.Addr{}
if err := socksAddr.ParseFrom(ln.Addr().String()); err != nil {
log.Warn(err)
}
// Issue: may not reachable when host has multi-interface
socksAddr.Host, _, _ = net.SplitHostPort(conn.LocalAddr().String())
socksAddr.Type = 0
reply := gosocks5.NewReply(gosocks5.Succeeded, &socksAddr)
log.Trace(reply)
if err := reply.Write(conn); err != nil {
log.Error(err)
ln.Close()
return err
}
log = log.WithFields(map[string]any{
"bind": fmt.Sprintf("%s/%s", ln.Addr(), ln.Addr().Network()),
})
log.Debugf("bind on %s OK", ln.Addr())
h.serveBind(ctx, conn, ln, log)
return nil
}
func (h *socks5Handler) serveBind(ctx context.Context, conn net.Conn, ln net.Listener, log logger.Logger) {
var rc net.Conn
accept := func() <-chan error {
errc := make(chan error, 1)
go func() {
defer close(errc)
defer ln.Close()
c, err := ln.Accept()
if err != nil {
errc <- err
}
rc = c
}()
return errc
}
pc1, pc2 := net.Pipe()
pipe := func() <-chan error {
errc := make(chan error, 1)
go func() {
defer close(errc)
defer pc1.Close()
errc <- xnet.Transport(conn, pc1)
}()
return errc
}
defer pc2.Close()
select {
case err := <-accept():
if err != nil {
log.Error(err)
reply := gosocks5.NewReply(gosocks5.Failure, nil)
log.Trace(reply)
if err := reply.Write(pc2); err != nil {
log.Error(err)
}
return
}
defer rc.Close()
log.Debugf("peer %s accepted", rc.RemoteAddr())
log = log.WithFields(map[string]any{
"local": rc.LocalAddr().String(),
"remote": rc.RemoteAddr().String(),
})
raddr := gosocks5.Addr{}
raddr.ParseFrom(rc.RemoteAddr().String())
reply := gosocks5.NewReply(gosocks5.Succeeded, &raddr)
log.Trace(reply)
if err := reply.Write(pc2); err != nil {
log.Error(err)
}
start := time.Now()
log.Debugf("%s <-> %s", rc.LocalAddr(), rc.RemoteAddr())
netpkg.Transport(pc2, rc)
log.WithFields(map[string]any{"duration": time.Since(start)}).
Debugf("%s >-< %s", rc.LocalAddr(), rc.RemoteAddr())
case err := <-pipe():
if err != nil {
log.Error(err)
}
ln.Close()
return
}
}