package socks import ( "context" "io" "time" "github.com/xtls/xray-core/common" "github.com/xtls/xray-core/common/buf" "github.com/xtls/xray-core/common/log" "github.com/xtls/xray-core/common/net" "github.com/xtls/xray-core/common/protocol" udp_proto "github.com/xtls/xray-core/common/protocol/udp" "github.com/xtls/xray-core/common/session" "github.com/xtls/xray-core/common/signal" "github.com/xtls/xray-core/common/task" "github.com/xtls/xray-core/core" "github.com/xtls/xray-core/features" "github.com/xtls/xray-core/features/policy" "github.com/xtls/xray-core/features/routing" "github.com/xtls/xray-core/transport/internet" "github.com/xtls/xray-core/transport/internet/udp" ) // Server is a SOCKS 5 proxy server type Server struct { config *ServerConfig policyManager policy.Manager } // NewServer creates a new Server object. func NewServer(ctx context.Context, config *ServerConfig) (*Server, error) { v := core.MustFromContext(ctx) s := &Server{ config: config, policyManager: v.GetFeature(policy.ManagerType()).(policy.Manager), } return s, nil } func (s *Server) policy() policy.Session { config := s.config p := s.policyManager.ForLevel(config.UserLevel) if config.Timeout > 0 { features.PrintDeprecatedFeatureWarning("Socks timeout") } if config.Timeout > 0 && config.UserLevel == 0 { p.Timeouts.ConnectionIdle = time.Duration(config.Timeout) * time.Second } return p } // Network implements proxy.Inbound. func (s *Server) Network() []net.Network { list := []net.Network{net.Network_TCP} if s.config.UdpEnabled { list = append(list, net.Network_UDP) } return list } // Process implements proxy.Inbound. func (s *Server) Process(ctx context.Context, network net.Network, conn internet.Connection, dispatcher routing.Dispatcher) error { if inbound := session.InboundFromContext(ctx); inbound != nil { inbound.User = &protocol.MemoryUser{ Level: s.config.UserLevel, } } 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 routing.Dispatcher) error { plcy := s.policy() if err := conn.SetReadDeadline(time.Now().Add(plcy.Timeouts.Handshake)); err != nil { newError("failed to set deadline").Base(err).WriteToLog(session.ExportIDToError(ctx)) } inbound := session.InboundFromContext(ctx) if inbound == nil || !inbound.Gateway.IsValid() { return newError("inbound gateway not specified") } svrSession := &ServerSession{ config: s.config, address: inbound.Gateway.Address, port: inbound.Gateway.Port, clientAddress: inbound.Source.Address, } reader := &buf.BufferedReader{Reader: buf.NewReader(conn)} request, err := svrSession.Handshake(reader, conn) if err != nil { if inbound != nil && inbound.Source.IsValid() { log.Record(&log.AccessMessage{ From: inbound.Source, To: "", Status: log.AccessRejected, Reason: err, }) } return newError("failed to read request").Base(err) } if request.User != nil { inbound.User.Email = request.User.Email } if err := conn.SetReadDeadline(time.Time{}); err != nil { newError("failed to clear deadline").Base(err).WriteToLog(session.ExportIDToError(ctx)) } if request.Command == protocol.RequestCommandTCP { dest := request.Destination() newError("TCP Connect request to ", dest).WriteToLog(session.ExportIDToError(ctx)) if inbound != nil && inbound.Source.IsValid() { ctx = log.ContextWithAccessMessage(ctx, &log.AccessMessage{ From: inbound.Source, To: dest, Status: log.AccessAccepted, Reason: "", }) } return s.transport(ctx, reader, conn, dest, dispatcher, inbound) } if request.Command == protocol.RequestCommandUDP { return s.handleUDP(conn) } return nil } func (*Server) handleUDP(c io.Reader) error { // The TCP connection closes after this method returns. We need to wait until // the client closes it. return common.Error2(io.Copy(buf.DiscardBytes, c)) } func (s *Server) transport(ctx context.Context, reader io.Reader, writer io.Writer, dest net.Destination, dispatcher routing.Dispatcher, inbound *session.Inbound) error { ctx, cancel := context.WithCancel(ctx) timer := signal.CancelAfterInactivity(ctx, cancel, s.policy().Timeouts.ConnectionIdle) if inbound != nil { inbound.Timer = timer } plcy := s.policy() ctx = policy.ContextWithBufferPolicy(ctx, plcy.Buffer) link, err := dispatcher.Dispatch(ctx, dest) if err != nil { return err } requestDone := func() error { defer timer.SetTimeout(plcy.Timeouts.DownlinkOnly) if err := buf.Copy(buf.NewReader(reader), link.Writer, buf.UpdateActivity(timer)); err != nil { return newError("failed to transport all TCP request").Base(err) } return nil } responseDone := func() error { defer timer.SetTimeout(plcy.Timeouts.UplinkOnly) v2writer := buf.NewWriter(writer) if err := buf.Copy(link.Reader, v2writer, buf.UpdateActivity(timer)); err != nil { return newError("failed to transport all TCP response").Base(err) } return nil } var requestDonePost = task.OnSuccess(requestDone, task.Close(link.Writer)) if err := task.Run(ctx, requestDonePost, responseDone); err != nil { common.Interrupt(link.Reader) common.Interrupt(link.Writer) return newError("connection ends").Base(err) } return nil } func (s *Server) handleUDPPayload(ctx context.Context, conn internet.Connection, dispatcher routing.Dispatcher) error { udpServer := udp.NewDispatcher(dispatcher, func(ctx context.Context, packet *udp_proto.Packet) { payload := packet.Payload newError("writing back UDP response with ", payload.Len(), " bytes").AtDebug().WriteToLog(session.ExportIDToError(ctx)) request := protocol.RequestHeaderFromContext(ctx) if request == nil { return } if payload.UDP != nil { request = &protocol.RequestHeader{ User: request.User, Address: net.IPAddress(payload.UDP.IP), Port: net.Port(payload.UDP.Port), } } udpMessage, err := EncodeUDPPacket(request, payload.Bytes()) payload.Release() defer udpMessage.Release() if err != nil { newError("failed to write UDP response").AtWarning().Base(err).WriteToLog(session.ExportIDToError(ctx)) } conn.Write(udpMessage.Bytes()) }) if inbound := session.InboundFromContext(ctx); inbound != nil && inbound.Source.IsValid() { newError("client UDP connection from ", inbound.Source).WriteToLog(session.ExportIDToError(ctx)) } var dest net.Destination reader := buf.NewPacketReader(conn) for { mpayload, err := reader.ReadMultiBuffer() if err != nil { return err } for _, payload := range mpayload { request, err := DecodeUDPPacket(payload) if err != nil { newError("failed to parse UDP request").Base(err).WriteToLog(session.ExportIDToError(ctx)) payload.Release() continue } if payload.IsEmpty() { payload.Release() continue } currentPacketCtx := ctx newError("send packet to ", request.Destination(), " with ", payload.Len(), " bytes").AtDebug().WriteToLog(session.ExportIDToError(ctx)) if inbound := session.InboundFromContext(ctx); inbound != nil && inbound.Source.IsValid() { currentPacketCtx = log.ContextWithAccessMessage(ctx, &log.AccessMessage{ From: inbound.Source, To: request.Destination(), Status: log.AccessAccepted, Reason: "", }) } payload.UDP = &net.UDPAddr{ IP: request.Address.IP(), Port: int(request.Port), } if dest.Network == 0 { dest = request.Destination() // JUST FOLLOW THE FIREST PACKET } currentPacketCtx = protocol.ContextWithRequestHeader(currentPacketCtx, request) udpServer.Dispatch(currentPacketCtx, dest, payload) } } } func init() { common.Must(common.RegisterConfig((*ServerConfig)(nil), func(ctx context.Context, config interface{}) (interface{}, error) { return NewServer(ctx, config.(*ServerConfig)) })) }