add socks

pkg/handler/socks/v5/handler.go

@@ -0,0 +1,125 @@
+package v5
+
+import (
+	"context"
+	"net"
+	"time"
+
+	"github.com/go-gost/gosocks5"
+	"github.com/go-gost/gost/pkg/bypass"
+	"github.com/go-gost/gost/pkg/chain"
+	"github.com/go-gost/gost/pkg/handler"
+	"github.com/go-gost/gost/pkg/logger"
+	md "github.com/go-gost/gost/pkg/metadata"
+	"github.com/go-gost/gost/pkg/registry"
+)
+
+const (
+	// MethodTLS is an extended SOCKS5 method with tls encryption support.
+	MethodTLS uint8 = 0x80
+	// MethodTLSAuth is an extended SOCKS5 method with tls encryption and authentication support.
+	MethodTLSAuth uint8 = 0x82
+	// MethodMux is an extended SOCKS5 method for stream multiplexing.
+	MethodMux = 0x88
+)
+
+const (
+	// CmdMuxBind is an extended SOCKS5 request CMD for
+	// multiplexing transport with the binding server.
+	CmdMuxBind uint8 = 0xF2
+	// CmdUDPTun is an extended SOCKS5 request CMD for UDP over TCP.
+	CmdUDPTun uint8 = 0xF3
+)
+
+func init() {
+	registry.RegisterHandler("socks5", NewHandler)
+	registry.RegisterHandler("socks", NewHandler)
+}
+
+type socks5Handler struct {
+	selector gosocks5.Selector
+	chain    *chain.Chain
+	bypass   bypass.Bypass
+	logger   logger.Logger
+	md       metadata
+}
+
+func NewHandler(opts ...handler.Option) handler.Handler {
+	options := &handler.Options{}
+	for _, opt := range opts {
+		opt(options)
+	}
+
+	return &socks5Handler{
+		chain:  options.Chain,
+		bypass: options.Bypass,
+		logger: options.Logger,
+	}
+}
+
+func (h *socks5Handler) Init(md md.Metadata) (err error) {
+	if err := h.parseMetadata(md); err != nil {
+		return err
+	}
+
+	h.selector = &serverSelector{
+		Authenticator: h.md.authenticator,
+		TLSConfig:     h.md.tlsConfig,
+		logger:        h.logger,
+		noTLS:         h.md.noTLS,
+	}
+
+	return
+}
+
+func (h *socks5Handler) Handle(ctx context.Context, conn net.Conn) {
+	defer conn.Close()
+
+	start := time.Now()
+
+	h.logger = h.logger.WithFields(map[string]interface{}{
+		"remote": conn.RemoteAddr().String(),
+		"local":  conn.LocalAddr().String(),
+	})
+
+	h.logger.Infof("%s <> %s", conn.RemoteAddr(), conn.LocalAddr())
+	defer func() {
+		h.logger.WithFields(map[string]interface{}{
+			"duration": time.Since(start),
+		}).Infof("%s >< %s", conn.RemoteAddr(), conn.LocalAddr())
+	}()
+
+	if h.md.readTimeout > 0 {
+		conn.SetReadDeadline(time.Now().Add(h.md.readTimeout))
+	}
+
+	conn = gosocks5.ServerConn(conn, h.selector)
+	req, err := gosocks5.ReadRequest(conn)
+	if err != nil {
+		h.logger.Error(err)
+		return
+	}
+	conn.SetReadDeadline(time.Time{})
+
+	if h.logger.IsLevelEnabled(logger.DebugLevel) {
+		h.logger.Debug(req)
+	}
+
+	switch req.Cmd {
+	case gosocks5.CmdConnect:
+		h.handleConnect(ctx, conn, req.Addr.String())
+	case gosocks5.CmdBind:
+		h.handleBind(ctx, conn, req)
+	case CmdMuxBind:
+	case gosocks5.CmdUdp:
+	case CmdUDPTun:
+	default:
+		h.logger.Errorf("unknown cmd: %d", req.Cmd)
+		resp := gosocks5.NewReply(gosocks5.CmdUnsupported, nil)
+		resp.Write(conn)
+		if h.logger.IsLevelEnabled(logger.DebugLevel) {
+			h.logger.Debug(resp)
+		}
+		return
+	}
+}