v1.0.0

proxy/shadowsocks/client.go

@@ -0,0 +1,182 @@
+// +build !confonly
+
+package shadowsocks
+
+import (
+	"context"
+
+	"github.com/xtls/xray-core/v1/common"
+	"github.com/xtls/xray-core/v1/common/buf"
+	"github.com/xtls/xray-core/v1/common/net"
+	"github.com/xtls/xray-core/v1/common/protocol"
+	"github.com/xtls/xray-core/v1/common/retry"
+	"github.com/xtls/xray-core/v1/common/session"
+	"github.com/xtls/xray-core/v1/common/signal"
+	"github.com/xtls/xray-core/v1/common/task"
+	"github.com/xtls/xray-core/v1/core"
+	"github.com/xtls/xray-core/v1/features/policy"
+	"github.com/xtls/xray-core/v1/transport"
+	"github.com/xtls/xray-core/v1/transport/internet"
+)
+
+// Client is a inbound handler for Shadowsocks protocol
+type Client struct {
+	serverPicker  protocol.ServerPicker
+	policyManager policy.Manager
+}
+
+// NewClient create a new Shadowsocks client.
+func NewClient(ctx context.Context, config *ClientConfig) (*Client, error) {
+	serverList := protocol.NewServerList()
+	for _, rec := range config.Server {
+		s, err := protocol.NewServerSpecFromPB(rec)
+		if err != nil {
+			return nil, newError("failed to parse server spec").Base(err)
+		}
+		serverList.AddServer(s)
+	}
+	if serverList.Size() == 0 {
+		return nil, newError("0 server")
+	}
+
+	v := core.MustFromContext(ctx)
+	client := &Client{
+		serverPicker:  protocol.NewRoundRobinServerPicker(serverList),
+		policyManager: v.GetFeature(policy.ManagerType()).(policy.Manager),
+	}
+	return client, nil
+}
+
+// Process implements OutboundHandler.Process().
+func (c *Client) Process(ctx context.Context, link *transport.Link, dialer internet.Dialer) error {
+	outbound := session.OutboundFromContext(ctx)
+	if outbound == nil || !outbound.Target.IsValid() {
+		return newError("target not specified")
+	}
+	destination := outbound.Target
+	network := destination.Network
+
+	var server *protocol.ServerSpec
+	var conn internet.Connection
+
+	err := retry.ExponentialBackoff(5, 100).On(func() error {
+		server = c.serverPicker.PickServer()
+		dest := server.Destination()
+		dest.Network = network
+		rawConn, err := dialer.Dial(ctx, dest)
+		if err != nil {
+			return err
+		}
+		conn = rawConn
+
+		return nil
+	})
+	if err != nil {
+		return newError("failed to find an available destination").AtWarning().Base(err)
+	}
+	newError("tunneling request to ", destination, " via ", server.Destination()).WriteToLog(session.ExportIDToError(ctx))
+
+	defer conn.Close()
+
+	request := &protocol.RequestHeader{
+		Version: Version,
+		Address: destination.Address,
+		Port:    destination.Port,
+	}
+	if destination.Network == net.Network_TCP {
+		request.Command = protocol.RequestCommandTCP
+	} else {
+		request.Command = protocol.RequestCommandUDP
+	}
+
+	user := server.PickUser()
+	_, ok := user.Account.(*MemoryAccount)
+	if !ok {
+		return newError("user account is not valid")
+	}
+	request.User = user
+
+	sessionPolicy := c.policyManager.ForLevel(user.Level)
+	ctx, cancel := context.WithCancel(ctx)
+	timer := signal.CancelAfterInactivity(ctx, cancel, sessionPolicy.Timeouts.ConnectionIdle)
+
+	if request.Command == protocol.RequestCommandTCP {
+		bufferedWriter := buf.NewBufferedWriter(buf.NewWriter(conn))
+		bodyWriter, err := WriteTCPRequest(request, bufferedWriter)
+		if err != nil {
+			return newError("failed to write request").Base(err)
+		}
+
+		if err := bufferedWriter.SetBuffered(false); err != nil {
+			return err
+		}
+
+		requestDone := func() error {
+			defer timer.SetTimeout(sessionPolicy.Timeouts.DownlinkOnly)
+			return buf.Copy(link.Reader, bodyWriter, buf.UpdateActivity(timer))
+		}
+
+		responseDone := func() error {
+			defer timer.SetTimeout(sessionPolicy.Timeouts.UplinkOnly)
+
+			responseReader, err := ReadTCPResponse(user, conn)
+			if err != nil {
+				return err
+			}
+
+			return buf.Copy(responseReader, link.Writer, buf.UpdateActivity(timer))
+		}
+
+		var responseDoneAndCloseWriter = task.OnSuccess(responseDone, task.Close(link.Writer))
+		if err := task.Run(ctx, requestDone, responseDoneAndCloseWriter); err != nil {
+			return newError("connection ends").Base(err)
+		}
+
+		return nil
+	}
+
+	if request.Command == protocol.RequestCommandUDP {
+		writer := &buf.SequentialWriter{Writer: &UDPWriter{
+			Writer:  conn,
+			Request: request,
+		}}
+
+		requestDone := func() error {
+			defer timer.SetTimeout(sessionPolicy.Timeouts.DownlinkOnly)
+
+			if err := buf.Copy(link.Reader, writer, buf.UpdateActivity(timer)); err != nil {
+				return newError("failed to transport all UDP request").Base(err)
+			}
+			return nil
+		}
+
+		responseDone := func() error {
+			defer timer.SetTimeout(sessionPolicy.Timeouts.UplinkOnly)
+
+			reader := &UDPReader{
+				Reader: conn,
+				User:   user,
+			}
+
+			if err := buf.Copy(reader, link.Writer, buf.UpdateActivity(timer)); err != nil {
+				return newError("failed to transport all UDP response").Base(err)
+			}
+			return nil
+		}
+
+		var responseDoneAndCloseWriter = task.OnSuccess(responseDone, task.Close(link.Writer))
+		if err := task.Run(ctx, requestDone, responseDoneAndCloseWriter); err != nil {
+			return newError("connection ends").Base(err)
+		}
+
+		return nil
+	}
+
+	return nil
+}
+
+func init() {
+	common.Must(common.RegisterConfig((*ClientConfig)(nil), func(ctx context.Context, config interface{}) (interface{}, error) {
+		return NewClient(ctx, config.(*ClientConfig))
+	}))
+}