x/connector/relay/bind.go
2022-03-14 20:27:14 +08:00

134 lines
3.2 KiB
Go

package relay
import (
"context"
"fmt"
"net"
"strconv"
"github.com/go-gost/gost/v3/pkg/common/util/udp"
"github.com/go-gost/gost/v3/pkg/connector"
"github.com/go-gost/gost/v3/pkg/logger"
"github.com/go-gost/relay"
"github.com/go-gost/x/internal/util/mux"
relay_util "github.com/go-gost/x/internal/util/relay"
)
// Bind implements connector.Binder.
func (c *relayConnector) Bind(ctx context.Context, conn net.Conn, network, address string, opts ...connector.BindOption) (net.Listener, error) {
log := c.options.Logger.WithFields(map[string]any{
"network": network,
"address": address,
})
log.Infof("bind on %s/%s", address, network)
options := connector.BindOptions{}
for _, opt := range opts {
opt(&options)
}
switch network {
case "tcp", "tcp4", "tcp6":
return c.bindTCP(ctx, conn, network, address, log)
case "udp", "udp4", "udp6":
return c.bindUDP(ctx, conn, network, address, &options, log)
default:
err := fmt.Errorf("network %s is unsupported", network)
log.Error(err)
return nil, err
}
}
func (c *relayConnector) bindTCP(ctx context.Context, conn net.Conn, network, address string, log logger.Logger) (net.Listener, error) {
laddr, err := c.bind(conn, relay.BIND, network, address)
if err != nil {
return nil, err
}
log.Debugf("bind on %s/%s OK", laddr, laddr.Network())
session, err := mux.ServerSession(conn)
if err != nil {
return nil, err
}
return &tcpListener{
addr: laddr,
session: session,
logger: log,
}, nil
}
func (c *relayConnector) bindUDP(ctx context.Context, conn net.Conn, network, address string, opts *connector.BindOptions, log logger.Logger) (net.Listener, error) {
laddr, err := c.bind(conn, relay.FUDP|relay.BIND, network, address)
if err != nil {
return nil, err
}
log.Debugf("bind on %s/%s OK", laddr, laddr.Network())
ln := udp.NewListener(
relay_util.UDPTunClientPacketConn(conn),
laddr,
opts.Backlog,
opts.UDPDataQueueSize, opts.UDPDataBufferSize,
opts.UDPConnTTL,
log)
return ln, nil
}
func (c *relayConnector) bind(conn net.Conn, cmd uint8, network, address string) (net.Addr, error) {
req := relay.Request{
Version: relay.Version1,
Flags: cmd,
}
if c.options.Auth != nil {
pwd, _ := c.options.Auth.Password()
req.Features = append(req.Features, &relay.UserAuthFeature{
Username: c.options.Auth.Username(),
Password: pwd,
})
}
fa := &relay.AddrFeature{}
fa.ParseFrom(address)
req.Features = append(req.Features, fa)
if _, err := req.WriteTo(conn); err != nil {
return nil, err
}
// first reply, bind status
resp := relay.Response{}
if _, err := resp.ReadFrom(conn); err != nil {
return nil, err
}
if resp.Status != relay.StatusOK {
return nil, fmt.Errorf("bind on %s/%s failed", address, network)
}
var addr string
for _, f := range resp.Features {
if f.Type() == relay.FeatureAddr {
if fa, ok := f.(*relay.AddrFeature); ok {
addr = net.JoinHostPort(fa.Host, strconv.Itoa(int(fa.Port)))
}
}
}
var baddr net.Addr
var err error
switch network {
case "tcp", "tcp4", "tcp6":
baddr, err = net.ResolveTCPAddr(network, addr)
case "udp", "udp4", "udp6":
baddr, err = net.ResolveUDPAddr(network, addr)
default:
err = fmt.Errorf("unknown network %s", network)
}
if err != nil {
return nil, err
}
return baddr, nil
}