1// +build !confonly
2
3package shadowsocks
4
5import (
6	"context"
7	"time"
8
9	core "github.com/v2fly/v2ray-core/v4"
10	"github.com/v2fly/v2ray-core/v4/common"
11	"github.com/v2fly/v2ray-core/v4/common/buf"
12	"github.com/v2fly/v2ray-core/v4/common/log"
13	"github.com/v2fly/v2ray-core/v4/common/net"
14	"github.com/v2fly/v2ray-core/v4/common/protocol"
15	udp_proto "github.com/v2fly/v2ray-core/v4/common/protocol/udp"
16	"github.com/v2fly/v2ray-core/v4/common/session"
17	"github.com/v2fly/v2ray-core/v4/common/signal"
18	"github.com/v2fly/v2ray-core/v4/common/task"
19	"github.com/v2fly/v2ray-core/v4/features/policy"
20	"github.com/v2fly/v2ray-core/v4/features/routing"
21	"github.com/v2fly/v2ray-core/v4/transport/internet"
22	"github.com/v2fly/v2ray-core/v4/transport/internet/udp"
23)
24
25type Server struct {
26	config        *ServerConfig
27	user          *protocol.MemoryUser
28	policyManager policy.Manager
29}
30
31// NewServer create a new Shadowsocks server.
32func NewServer(ctx context.Context, config *ServerConfig) (*Server, error) {
33	if config.GetUser() == nil {
34		return nil, newError("user is not specified")
35	}
36
37	mUser, err := config.User.ToMemoryUser()
38	if err != nil {
39		return nil, newError("failed to parse user account").Base(err)
40	}
41
42	v := core.MustFromContext(ctx)
43	s := &Server{
44		config:        config,
45		user:          mUser,
46		policyManager: v.GetFeature(policy.ManagerType()).(policy.Manager),
47	}
48
49	return s, nil
50}
51
52func (s *Server) Network() []net.Network {
53	list := s.config.Network
54	if len(list) == 0 {
55		list = append(list, net.Network_TCP)
56	}
57	if s.config.UdpEnabled {
58		list = append(list, net.Network_UDP)
59	}
60	return list
61}
62
63func (s *Server) Process(ctx context.Context, network net.Network, conn internet.Connection, dispatcher routing.Dispatcher) error {
64	switch network {
65	case net.Network_TCP:
66		return s.handleConnection(ctx, conn, dispatcher)
67	case net.Network_UDP:
68		return s.handlerUDPPayload(ctx, conn, dispatcher)
69	default:
70		return newError("unknown network: ", network)
71	}
72}
73
74func (s *Server) handlerUDPPayload(ctx context.Context, conn internet.Connection, dispatcher routing.Dispatcher) error {
75	udpServer := udp.NewDispatcher(dispatcher, func(ctx context.Context, packet *udp_proto.Packet) {
76		request := protocol.RequestHeaderFromContext(ctx)
77		if request == nil {
78			return
79		}
80
81		payload := packet.Payload
82		data, err := EncodeUDPPacket(request, payload.Bytes())
83		payload.Release()
84		if err != nil {
85			newError("failed to encode UDP packet").Base(err).AtWarning().WriteToLog(session.ExportIDToError(ctx))
86			return
87		}
88		defer data.Release()
89
90		conn.Write(data.Bytes())
91	})
92
93	inbound := session.InboundFromContext(ctx)
94	if inbound == nil {
95		panic("no inbound metadata")
96	}
97	inbound.User = s.user
98
99	reader := buf.NewPacketReader(conn)
100	for {
101		mpayload, err := reader.ReadMultiBuffer()
102		if err != nil {
103			break
104		}
105
106		for _, payload := range mpayload {
107			request, data, err := DecodeUDPPacket(s.user, payload)
108			if err != nil {
109				if inbound := session.InboundFromContext(ctx); inbound != nil && inbound.Source.IsValid() {
110					newError("dropping invalid UDP packet from: ", inbound.Source).Base(err).WriteToLog(session.ExportIDToError(ctx))
111					log.Record(&log.AccessMessage{
112						From:   inbound.Source,
113						To:     "",
114						Status: log.AccessRejected,
115						Reason: err,
116					})
117				}
118				payload.Release()
119				continue
120			}
121
122			currentPacketCtx := ctx
123			dest := request.Destination()
124			if inbound.Source.IsValid() {
125				currentPacketCtx = log.ContextWithAccessMessage(ctx, &log.AccessMessage{
126					From:   inbound.Source,
127					To:     dest,
128					Status: log.AccessAccepted,
129					Reason: "",
130					Email:  request.User.Email,
131				})
132			}
133			newError("tunnelling request to ", dest).WriteToLog(session.ExportIDToError(currentPacketCtx))
134
135			currentPacketCtx = protocol.ContextWithRequestHeader(currentPacketCtx, request)
136			udpServer.Dispatch(currentPacketCtx, dest, data)
137		}
138	}
139
140	return nil
141}
142
143func (s *Server) handleConnection(ctx context.Context, conn internet.Connection, dispatcher routing.Dispatcher) error {
144	sessionPolicy := s.policyManager.ForLevel(s.user.Level)
145	conn.SetReadDeadline(time.Now().Add(sessionPolicy.Timeouts.Handshake))
146
147	bufferedReader := buf.BufferedReader{Reader: buf.NewReader(conn)}
148	request, bodyReader, err := ReadTCPSession(s.user, &bufferedReader)
149	if err != nil {
150		log.Record(&log.AccessMessage{
151			From:   conn.RemoteAddr(),
152			To:     "",
153			Status: log.AccessRejected,
154			Reason: err,
155		})
156		return newError("failed to create request from: ", conn.RemoteAddr()).Base(err)
157	}
158	conn.SetReadDeadline(time.Time{})
159
160	inbound := session.InboundFromContext(ctx)
161	if inbound == nil {
162		panic("no inbound metadata")
163	}
164	inbound.User = s.user
165
166	dest := request.Destination()
167	ctx = log.ContextWithAccessMessage(ctx, &log.AccessMessage{
168		From:   conn.RemoteAddr(),
169		To:     dest,
170		Status: log.AccessAccepted,
171		Reason: "",
172		Email:  request.User.Email,
173	})
174	newError("tunnelling request to ", dest).WriteToLog(session.ExportIDToError(ctx))
175
176	ctx, cancel := context.WithCancel(ctx)
177	timer := signal.CancelAfterInactivity(ctx, cancel, sessionPolicy.Timeouts.ConnectionIdle)
178
179	ctx = policy.ContextWithBufferPolicy(ctx, sessionPolicy.Buffer)
180	link, err := dispatcher.Dispatch(ctx, dest)
181	if err != nil {
182		return err
183	}
184
185	responseDone := func() error {
186		defer timer.SetTimeout(sessionPolicy.Timeouts.UplinkOnly)
187
188		bufferedWriter := buf.NewBufferedWriter(buf.NewWriter(conn))
189		responseWriter, err := WriteTCPResponse(request, bufferedWriter)
190		if err != nil {
191			return newError("failed to write response").Base(err)
192		}
193
194		{
195			payload, err := link.Reader.ReadMultiBuffer()
196			if err != nil {
197				return err
198			}
199			if err := responseWriter.WriteMultiBuffer(payload); err != nil {
200				return err
201			}
202		}
203
204		if err := bufferedWriter.SetBuffered(false); err != nil {
205			return err
206		}
207
208		if err := buf.Copy(link.Reader, responseWriter, buf.UpdateActivity(timer)); err != nil {
209			return newError("failed to transport all TCP response").Base(err)
210		}
211
212		return nil
213	}
214
215	requestDone := func() error {
216		defer timer.SetTimeout(sessionPolicy.Timeouts.DownlinkOnly)
217
218		if err := buf.Copy(bodyReader, link.Writer, buf.UpdateActivity(timer)); err != nil {
219			return newError("failed to transport all TCP request").Base(err)
220		}
221
222		return nil
223	}
224
225	var requestDoneAndCloseWriter = task.OnSuccess(requestDone, task.Close(link.Writer))
226	if err := task.Run(ctx, requestDoneAndCloseWriter, responseDone); err != nil {
227		common.Interrupt(link.Reader)
228		common.Interrupt(link.Writer)
229		return newError("connection ends").Base(err)
230	}
231
232	return nil
233}
234
235func init() {
236	common.Must(common.RegisterConfig((*ServerConfig)(nil), func(ctx context.Context, config interface{}) (interface{}, error) {
237		return NewServer(ctx, config.(*ServerConfig))
238	}))
239}
240