package socks import ( "context" "io" "time" "v2ray.com/core" "v2ray.com/core/common" "v2ray.com/core/common/buf" "v2ray.com/core/common/log" "v2ray.com/core/common/net" "v2ray.com/core/common/protocol" "v2ray.com/core/common/signal" "v2ray.com/core/proxy" "v2ray.com/core/transport/internet" "v2ray.com/core/transport/internet/udp" ) // Server is a SOCKS 5 proxy server type Server struct { config *ServerConfig v *core.Instance } // NewServer creates a new Server object. func NewServer(ctx context.Context, config *ServerConfig) (*Server, error) { s := &Server{ config: config, v: core.FromContext(ctx), } if s.v == nil { return nil, newError("V is not in context.") } return s, nil } func (s *Server) policy() core.Policy { config := s.config p := s.v.PolicyManager().ForLevel(config.UserLevel) if config.Timeout > 0 && config.UserLevel == 0 { p.Timeouts.ConnectionIdle = time.Duration(config.Timeout) * time.Second } return p } func (s *Server) Network() net.NetworkList { list := net.NetworkList{ Network: []net.Network{net.Network_TCP}, } if s.config.UdpEnabled { list.Network = append(list.Network, net.Network_UDP) } return list } func (s *Server) Process(ctx context.Context, network net.Network, conn internet.Connection, dispatcher core.Dispatcher) error { switch network { case net.Network_TCP: return s.processTCP(ctx, conn, dispatcher) case net.Network_UDP: return s.handleUDPPayload(ctx, conn, dispatcher) default: return newError("unknown network: ", network) } } func (s *Server) processTCP(ctx context.Context, conn internet.Connection, dispatcher core.Dispatcher) error { conn.SetReadDeadline(time.Now().Add(s.policy().Timeouts.Handshake)) reader := buf.NewBufferedReader(buf.NewReader(conn)) inboundDest, ok := proxy.InboundEntryPointFromContext(ctx) if !ok { return newError("inbound entry point not specified") } session := &ServerSession{ config: s.config, port: inboundDest.Port, } request, err := session.Handshake(reader, conn) if err != nil { if source, ok := proxy.SourceFromContext(ctx); ok { log.Record(&log.AccessMessage{ From: source, To: "", Status: log.AccessRejected, Reason: err, }) } return newError("failed to read request").Base(err) } conn.SetReadDeadline(time.Time{}) if request.Command == protocol.RequestCommandTCP { dest := request.Destination() newError("TCP Connect request to ", dest).WriteToLog() if source, ok := proxy.SourceFromContext(ctx); ok { log.Record(&log.AccessMessage{ From: source, To: dest, Status: log.AccessAccepted, Reason: "", }) } return s.transport(ctx, reader, conn, dest, dispatcher) } if request.Command == protocol.RequestCommandUDP { return s.handleUDP(conn) } return nil } func (*Server) handleUDP(c net.Conn) error { // The TCP connection closes after this method returns. We need to wait until // the client closes it. _, err := io.Copy(buf.DiscardBytes, c) return err } func (v *Server) transport(ctx context.Context, reader io.Reader, writer io.Writer, dest net.Destination, dispatcher core.Dispatcher) error { ctx, cancel := context.WithCancel(ctx) timer := signal.CancelAfterInactivity(ctx, cancel, v.policy().Timeouts.ConnectionIdle) ray, err := dispatcher.Dispatch(ctx, dest) if err != nil { return err } input := ray.InboundInput() output := ray.InboundOutput() requestDone := signal.ExecuteAsync(func() error { defer input.Close() v2reader := buf.NewReader(reader) if err := buf.Copy(v2reader, input, buf.UpdateActivity(timer)); err != nil { return newError("failed to transport all TCP request").Base(err) } timer.SetTimeout(v.policy().Timeouts.DownlinkOnly) return nil }) responseDone := signal.ExecuteAsync(func() error { v2writer := buf.NewWriter(writer) if err := buf.Copy(output, v2writer, buf.UpdateActivity(timer)); err != nil { return newError("failed to transport all TCP response").Base(err) } timer.SetTimeout(v.policy().Timeouts.UplinkOnly) return nil }) if err := signal.ErrorOrFinish2(ctx, requestDone, responseDone); err != nil { input.CloseError() output.CloseError() return newError("connection ends").Base(err) } return nil } func (v *Server) handleUDPPayload(ctx context.Context, conn internet.Connection, dispatcher core.Dispatcher) error { udpServer := udp.NewDispatcher(dispatcher) if source, ok := proxy.SourceFromContext(ctx); ok { newError("client UDP connection from ", source).WriteToLog() } reader := buf.NewReader(conn) for { mpayload, err := reader.ReadMultiBuffer() if err != nil { return err } for _, payload := range mpayload { request, data, err := DecodeUDPPacket(payload.Bytes()) if err != nil { newError("failed to parse UDP request").Base(err).WriteToLog() continue } if len(data) == 0 { continue } newError("send packet to ", request.Destination(), " with ", len(data), " bytes").AtDebug().WriteToLog() if source, ok := proxy.SourceFromContext(ctx); ok { log.Record(&log.AccessMessage{ From: source, To: request.Destination, Status: log.AccessAccepted, Reason: "", }) } dataBuf := buf.New() dataBuf.Append(data) udpServer.Dispatch(ctx, request.Destination(), dataBuf, func(payload *buf.Buffer) { defer payload.Release() newError("writing back UDP response with ", payload.Len(), " bytes").AtDebug().WriteToLog() udpMessage, err := EncodeUDPPacket(request, payload.Bytes()) defer udpMessage.Release() if err != nil { newError("failed to write UDP response").AtWarning().Base(err).WriteToLog() } conn.Write(udpMessage.Bytes()) }) } } } func init() { common.Must(common.RegisterConfig((*ServerConfig)(nil), func(ctx context.Context, config interface{}) (interface{}, error) { return NewServer(ctx, config.(*ServerConfig)) })) }