package shadowsocks import ( "context" "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/policy" "github.com/xtls/xray-core/features/routing" "github.com/xtls/xray-core/transport/internet" "github.com/xtls/xray-core/transport/internet/udp" ) type Server struct { config *ServerConfig user *protocol.MemoryUser policyManager policy.Manager } // NewServer create a new Shadowsocks server. func NewServer(ctx context.Context, config *ServerConfig) (*Server, error) { if config.GetUser() == nil { return nil, newError("user is not specified") } mUser, err := config.User.ToMemoryUser() if err != nil { return nil, newError("failed to parse user account").Base(err) } v := core.MustFromContext(ctx) s := &Server{ config: config, user: mUser, policyManager: v.GetFeature(policy.ManagerType()).(policy.Manager), } return s, nil } func (s *Server) Network() []net.Network { list := s.config.Network if len(list) == 0 { list = append(list, net.Network_TCP) } if s.config.UdpEnabled { list = append(list, net.Network_UDP) } return list } func (s *Server) Process(ctx context.Context, network net.Network, conn internet.Connection, dispatcher routing.Dispatcher) error { switch network { case net.Network_TCP: return s.handleConnection(ctx, conn, dispatcher) case net.Network_UDP: return s.handlerUDPPayload(ctx, conn, dispatcher) default: return newError("unknown network: ", network) } } func (s *Server) handlerUDPPayload(ctx context.Context, conn internet.Connection, dispatcher routing.Dispatcher) error { udpServer := udp.NewDispatcher(dispatcher, func(ctx context.Context, packet *udp_proto.Packet) { request := protocol.RequestHeaderFromContext(ctx) if request == nil { return } payload := packet.Payload if payload.UDP != nil { request = &protocol.RequestHeader{ User: request.User, Address: payload.UDP.Address, Port: payload.UDP.Port, } } data, err := EncodeUDPPacket(request, payload.Bytes()) payload.Release() if err != nil { newError("failed to encode UDP packet").Base(err).AtWarning().WriteToLog(session.ExportIDToError(ctx)) return } defer data.Release() conn.Write(data.Bytes()) }) inbound := session.InboundFromContext(ctx) if inbound == nil { panic("no inbound metadata") } inbound.User = s.user var dest net.Destination reader := buf.NewPacketReader(conn) for { mpayload, err := reader.ReadMultiBuffer() if err != nil { break } for _, payload := range mpayload { request, data, err := DecodeUDPPacket(s.user, payload) if err != nil { if inbound := session.InboundFromContext(ctx); inbound != nil && inbound.Source.IsValid() { newError("dropping invalid UDP packet from: ", inbound.Source).Base(err).WriteToLog(session.ExportIDToError(ctx)) log.Record(&log.AccessMessage{ From: inbound.Source, To: "", Status: log.AccessRejected, Reason: err, }) } payload.Release() continue } destination := request.Destination() currentPacketCtx := ctx if inbound.Source.IsValid() { currentPacketCtx = log.ContextWithAccessMessage(ctx, &log.AccessMessage{ From: inbound.Source, To: destination, Status: log.AccessAccepted, Reason: "", Email: request.User.Email, }) } newError("tunnelling request to ", destination).WriteToLog(session.ExportIDToError(currentPacketCtx)) data.UDP = &destination if dest.Network == 0 { dest = request.Destination() // JUST FOLLOW THE FIRST PACKET } currentPacketCtx = protocol.ContextWithRequestHeader(currentPacketCtx, request) udpServer.Dispatch(currentPacketCtx, dest, data) } } return nil } func (s *Server) handleConnection(ctx context.Context, conn internet.Connection, dispatcher routing.Dispatcher) error { sessionPolicy := s.policyManager.ForLevel(s.user.Level) conn.SetReadDeadline(time.Now().Add(sessionPolicy.Timeouts.Handshake)) bufferedReader := buf.BufferedReader{Reader: buf.NewReader(conn)} request, bodyReader, err := ReadTCPSession(s.user, &bufferedReader) if err != nil { log.Record(&log.AccessMessage{ From: conn.RemoteAddr(), To: "", Status: log.AccessRejected, Reason: err, }) return newError("failed to create request from: ", conn.RemoteAddr()).Base(err) } conn.SetReadDeadline(time.Time{}) inbound := session.InboundFromContext(ctx) if inbound == nil { panic("no inbound metadata") } inbound.User = s.user dest := request.Destination() ctx = log.ContextWithAccessMessage(ctx, &log.AccessMessage{ From: conn.RemoteAddr(), To: dest, Status: log.AccessAccepted, Reason: "", Email: request.User.Email, }) newError("tunnelling request to ", dest).WriteToLog(session.ExportIDToError(ctx)) ctx, cancel := context.WithCancel(ctx) timer := signal.CancelAfterInactivity(ctx, cancel, sessionPolicy.Timeouts.ConnectionIdle) ctx = policy.ContextWithBufferPolicy(ctx, sessionPolicy.Buffer) link, err := dispatcher.Dispatch(ctx, dest) if err != nil { return err } responseDone := func() error { defer timer.SetTimeout(sessionPolicy.Timeouts.UplinkOnly) bufferedWriter := buf.NewBufferedWriter(buf.NewWriter(conn)) responseWriter, err := WriteTCPResponse(request, bufferedWriter) if err != nil { return newError("failed to write response").Base(err) } { payload, err := link.Reader.ReadMultiBuffer() if err != nil { return err } if err := responseWriter.WriteMultiBuffer(payload); err != nil { return err } } if err := bufferedWriter.SetBuffered(false); err != nil { return err } if err := buf.Copy(link.Reader, responseWriter, buf.UpdateActivity(timer)); err != nil { return newError("failed to transport all TCP response").Base(err) } return nil } requestDone := func() error { defer timer.SetTimeout(sessionPolicy.Timeouts.DownlinkOnly) if err := buf.Copy(bodyReader, link.Writer, buf.UpdateActivity(timer)); err != nil { return newError("failed to transport all TCP request").Base(err) } return nil } var requestDoneAndCloseWriter = task.OnSuccess(requestDone, task.Close(link.Writer)) if err := task.Run(ctx, requestDoneAndCloseWriter, responseDone); err != nil { common.Interrupt(link.Reader) common.Interrupt(link.Writer) return newError("connection ends").Base(err) } return nil } func init() { common.Must(common.RegisterConfig((*ServerConfig)(nil), func(ctx context.Context, config interface{}) (interface{}, error) { return NewServer(ctx, config.(*ServerConfig)) })) }