add grpc tunnel

pkg/chain/transport.go

@@ -36,7 +36,9 @@ func (tr *Transport) Dial(ctx context.Context, addr string) (net.Conn, error) {
 }
 
 func (tr *Transport) dialOptions() []dialer.DialOption {
-	var opts []dialer.DialOption
+	opts := []dialer.DialOption{
+		dialer.HostDialOption(tr.addr),
+	}
 	if !tr.route.IsEmpty() {
 		opts = append(opts,
 			dialer.DialFuncDialOption(

pkg/common/util/grpc/proto/gost.pb.go

@@ -0,0 +1,148 @@
+// Code generated by protoc-gen-go. DO NOT EDIT.
+// versions:
+// 	protoc-gen-go v1.26.0
+// 	protoc        v3.12.4
+// source: gost.proto
+
+package proto
+
+import (
+	protoreflect "google.golang.org/protobuf/reflect/protoreflect"
+	protoimpl "google.golang.org/protobuf/runtime/protoimpl"
+	reflect "reflect"
+	sync "sync"
+)
+
+const (
+	// Verify that this generated code is sufficiently up-to-date.
+	_ = protoimpl.EnforceVersion(20 - protoimpl.MinVersion)
+	// Verify that runtime/protoimpl is sufficiently up-to-date.
+	_ = protoimpl.EnforceVersion(protoimpl.MaxVersion - 20)
+)
+
+type Chunk struct {
+	state         protoimpl.MessageState
+	sizeCache     protoimpl.SizeCache
+	unknownFields protoimpl.UnknownFields
+
+	Data []byte `protobuf:"bytes,1,opt,name=data,proto3" json:"data,omitempty"`
+}
+
+func (x *Chunk) Reset() {
+	*x = Chunk{}
+	if protoimpl.UnsafeEnabled {
+		mi := &file_gost_proto_msgTypes[0]
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		ms.StoreMessageInfo(mi)
+	}
+}
+
+func (x *Chunk) String() string {
+	return protoimpl.X.MessageStringOf(x)
+}
+
+func (*Chunk) ProtoMessage() {}
+
+func (x *Chunk) ProtoReflect() protoreflect.Message {
+	mi := &file_gost_proto_msgTypes[0]
+	if protoimpl.UnsafeEnabled && x != nil {
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		if ms.LoadMessageInfo() == nil {
+			ms.StoreMessageInfo(mi)
+		}
+		return ms
+	}
+	return mi.MessageOf(x)
+}
+
+// Deprecated: Use Chunk.ProtoReflect.Descriptor instead.
+func (*Chunk) Descriptor() ([]byte, []int) {
+	return file_gost_proto_rawDescGZIP(), []int{0}
+}
+
+func (x *Chunk) GetData() []byte {
+	if x != nil {
+		return x.Data
+	}
+	return nil
+}
+
+var File_gost_proto protoreflect.FileDescriptor
+
+var file_gost_proto_rawDesc = []byte{
+	0x0a, 0x0a, 0x67, 0x6f, 0x73, 0x74, 0x2e, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x22, 0x1b, 0x0a, 0x05,
+	0x43, 0x68, 0x75, 0x6e, 0x6b, 0x12, 0x12, 0x0a, 0x04, 0x64, 0x61, 0x74, 0x61, 0x18, 0x01, 0x20,
+	0x01, 0x28, 0x0c, 0x52, 0x04, 0x64, 0x61, 0x74, 0x61, 0x32, 0x29, 0x0a, 0x09, 0x47, 0x6f, 0x73,
+	0x74, 0x54, 0x75, 0x6e, 0x65, 0x6c, 0x12, 0x1c, 0x0a, 0x06, 0x54, 0x75, 0x6e, 0x6e, 0x65, 0x6c,
+	0x12, 0x06, 0x2e, 0x43, 0x68, 0x75, 0x6e, 0x6b, 0x1a, 0x06, 0x2e, 0x43, 0x68, 0x75, 0x6e, 0x6b,
+	0x28, 0x01, 0x30, 0x01, 0x42, 0x34, 0x5a, 0x32, 0x67, 0x69, 0x74, 0x68, 0x75, 0x62, 0x2e, 0x63,
+	0x6f, 0x6d, 0x2f, 0x67, 0x6f, 0x2d, 0x67, 0x6f, 0x73, 0x74, 0x2f, 0x67, 0x6f, 0x73, 0x74, 0x2f,
+	0x70, 0x6b, 0x67, 0x2f, 0x63, 0x6f, 0x6d, 0x6d, 0x6f, 0x6e, 0x2f, 0x75, 0x74, 0x69, 0x6c, 0x2f,
+	0x67, 0x72, 0x70, 0x63, 0x2f, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x62, 0x06, 0x70, 0x72, 0x6f, 0x74,
+	0x6f, 0x33,
+}
+
+var (
+	file_gost_proto_rawDescOnce sync.Once
+	file_gost_proto_rawDescData = file_gost_proto_rawDesc
+)
+
+func file_gost_proto_rawDescGZIP() []byte {
+	file_gost_proto_rawDescOnce.Do(func() {
+		file_gost_proto_rawDescData = protoimpl.X.CompressGZIP(file_gost_proto_rawDescData)
+	})
+	return file_gost_proto_rawDescData
+}
+
+var file_gost_proto_msgTypes = make([]protoimpl.MessageInfo, 1)
+var file_gost_proto_goTypes = []interface{}{
+	(*Chunk)(nil), // 0: Chunk
+}
+var file_gost_proto_depIdxs = []int32{
+	0, // 0: GostTunel.Tunnel:input_type -> Chunk
+	0, // 1: GostTunel.Tunnel:output_type -> Chunk
+	1, // [1:2] is the sub-list for method output_type
+	0, // [0:1] is the sub-list for method input_type
+	0, // [0:0] is the sub-list for extension type_name
+	0, // [0:0] is the sub-list for extension extendee
+	0, // [0:0] is the sub-list for field type_name
+}
+
+func init() { file_gost_proto_init() }
+func file_gost_proto_init() {
+	if File_gost_proto != nil {
+		return
+	}
+	if !protoimpl.UnsafeEnabled {
+		file_gost_proto_msgTypes[0].Exporter = func(v interface{}, i int) interface{} {
+			switch v := v.(*Chunk); i {
+			case 0:
+				return &v.state
+			case 1:
+				return &v.sizeCache
+			case 2:
+				return &v.unknownFields
+			default:
+				return nil
+			}
+		}
+	}
+	type x struct{}
+	out := protoimpl.TypeBuilder{
+		File: protoimpl.DescBuilder{
+			GoPackagePath: reflect.TypeOf(x{}).PkgPath(),
+			RawDescriptor: file_gost_proto_rawDesc,
+			NumEnums:      0,
+			NumMessages:   1,
+			NumExtensions: 0,
+			NumServices:   1,
+		},
+		GoTypes:           file_gost_proto_goTypes,
+		DependencyIndexes: file_gost_proto_depIdxs,
+		MessageInfos:      file_gost_proto_msgTypes,
+	}.Build()
+	File_gost_proto = out.File
+	file_gost_proto_rawDesc = nil
+	file_gost_proto_goTypes = nil
+	file_gost_proto_depIdxs = nil
+}

pkg/common/util/grpc/proto/gost.proto

@@ -0,0 +1,10 @@
+syntax = "proto3";
+option go_package = "github.com/go-gost/gost/pkg/common/util/grpc/proto";
+
+message Chunk {
+  bytes data = 1;
+}
+
+service GostTunel {
+  rpc Tunnel (stream Chunk) returns (stream Chunk);
+}

pkg/common/util/grpc/proto/gost_grpc.pb.go

@@ -0,0 +1,133 @@
+// Code generated by protoc-gen-go-grpc. DO NOT EDIT.
+
+package proto
+
+import (
+	context "context"
+	grpc "google.golang.org/grpc"
+	codes "google.golang.org/grpc/codes"
+	status "google.golang.org/grpc/status"
+)
+
+// This is a compile-time assertion to ensure that this generated file
+// is compatible with the grpc package it is being compiled against.
+// Requires gRPC-Go v1.32.0 or later.
+const _ = grpc.SupportPackageIsVersion7
+
+// GostTunelClient is the client API for GostTunel service.
+//
+// For semantics around ctx use and closing/ending streaming RPCs, please refer to https://pkg.go.dev/google.golang.org/grpc/?tab=doc#ClientConn.NewStream.
+type GostTunelClient interface {
+	Tunnel(ctx context.Context, opts ...grpc.CallOption) (GostTunel_TunnelClient, error)
+}
+
+type gostTunelClient struct {
+	cc grpc.ClientConnInterface
+}
+
+func NewGostTunelClient(cc grpc.ClientConnInterface) GostTunelClient {
+	return &gostTunelClient{cc}
+}
+
+func (c *gostTunelClient) Tunnel(ctx context.Context, opts ...grpc.CallOption) (GostTunel_TunnelClient, error) {
+	stream, err := c.cc.NewStream(ctx, &GostTunel_ServiceDesc.Streams[0], "/GostTunel/Tunnel", opts...)
+	if err != nil {
+		return nil, err
+	}
+	x := &gostTunelTunnelClient{stream}
+	return x, nil
+}
+
+type GostTunel_TunnelClient interface {
+	Send(*Chunk) error
+	Recv() (*Chunk, error)
+	grpc.ClientStream
+}
+
+type gostTunelTunnelClient struct {
+	grpc.ClientStream
+}
+
+func (x *gostTunelTunnelClient) Send(m *Chunk) error {
+	return x.ClientStream.SendMsg(m)
+}
+
+func (x *gostTunelTunnelClient) Recv() (*Chunk, error) {
+	m := new(Chunk)
+	if err := x.ClientStream.RecvMsg(m); err != nil {
+		return nil, err
+	}
+	return m, nil
+}
+
+// GostTunelServer is the server API for GostTunel service.
+// All implementations must embed UnimplementedGostTunelServer
+// for forward compatibility
+type GostTunelServer interface {
+	Tunnel(GostTunel_TunnelServer) error
+	mustEmbedUnimplementedGostTunelServer()
+}
+
+// UnimplementedGostTunelServer must be embedded to have forward compatible implementations.
+type UnimplementedGostTunelServer struct {
+}
+
+func (UnimplementedGostTunelServer) Tunnel(GostTunel_TunnelServer) error {
+	return status.Errorf(codes.Unimplemented, "method Tunnel not implemented")
+}
+func (UnimplementedGostTunelServer) mustEmbedUnimplementedGostTunelServer() {}
+
+// UnsafeGostTunelServer may be embedded to opt out of forward compatibility for this service.
+// Use of this interface is not recommended, as added methods to GostTunelServer will
+// result in compilation errors.
+type UnsafeGostTunelServer interface {
+	mustEmbedUnimplementedGostTunelServer()
+}
+
+func RegisterGostTunelServer(s grpc.ServiceRegistrar, srv GostTunelServer) {
+	s.RegisterService(&GostTunel_ServiceDesc, srv)
+}
+
+func _GostTunel_Tunnel_Handler(srv interface{}, stream grpc.ServerStream) error {
+	return srv.(GostTunelServer).Tunnel(&gostTunelTunnelServer{stream})
+}
+
+type GostTunel_TunnelServer interface {
+	Send(*Chunk) error
+	Recv() (*Chunk, error)
+	grpc.ServerStream
+}
+
+type gostTunelTunnelServer struct {
+	grpc.ServerStream
+}
+
+func (x *gostTunelTunnelServer) Send(m *Chunk) error {
+	return x.ServerStream.SendMsg(m)
+}
+
+func (x *gostTunelTunnelServer) Recv() (*Chunk, error) {
+	m := new(Chunk)
+	if err := x.ServerStream.RecvMsg(m); err != nil {
+		return nil, err
+	}
+	return m, nil
+}
+
+// GostTunel_ServiceDesc is the grpc.ServiceDesc for GostTunel service.
+// It's only intended for direct use with grpc.RegisterService,
+// and not to be introspected or modified (even as a copy)
+var GostTunel_ServiceDesc = grpc.ServiceDesc{
+	ServiceName: "GostTunel",
+	HandlerType: (*GostTunelServer)(nil),
+	Methods:     []grpc.MethodDesc{},
+	Streams: []grpc.StreamDesc{
+		{
+			StreamName:    "Tunnel",
+			Handler:       _GostTunel_Tunnel_Handler,
+			ServerStreams: true,
+			ClientStreams: true,
+		},
+	},
+	Metadata: "gost.proto",
+}

pkg/common/util/grpc/proto/protoc.sh

@@ -0,0 +1,3 @@
+protoc --go_out=. --go_opt=paths=source_relative \
+	--go-grpc_out=. --go-grpc_opt=paths=source_relative \
+	gost.proto

pkg/dialer/grpc/conn.go

@@ -0,0 +1,92 @@
+package grpc
+
+import (
+	"errors"
+	"io"
+	"net"
+	"time"
+
+	pb "github.com/go-gost/gost/pkg/common/util/grpc/proto"
+)
+
+type conn struct {
+	c          pb.GostTunel_TunnelClient
+	rb         []byte
+	localAddr  net.Addr
+	remoteAddr net.Addr
+	closed     chan struct{}
+}
+
+func (c *conn) Read(b []byte) (n int, err error) {
+	select {
+	case <-c.c.Context().Done():
+		err = c.c.Context().Err()
+		return
+	case <-c.closed:
+		err = io.ErrClosedPipe
+		return
+	default:
+	}
+
+	if len(c.rb) == 0 {
+		chunk, err := c.c.Recv()
+		if err != nil {
+			return 0, err
+		}
+		c.rb = chunk.Data
+	}
+
+	n = copy(b, c.rb)
+	c.rb = c.rb[n:]
+	return
+}
+
+func (c *conn) Write(b []byte) (n int, err error) {
+	select {
+	case <-c.c.Context().Done():
+		err = c.c.Context().Err()
+		return
+	case <-c.closed:
+		err = io.ErrClosedPipe
+		return
+	default:
+	}
+
+	if err = c.c.Send(&pb.Chunk{
+		Data: b,
+	}); err != nil {
+		return
+	}
+	n = len(b)
+	return
+}
+
+func (c *conn) Close() error {
+	select {
+	case <-c.closed:
+	default:
+		close(c.closed)
+	}
+
+	return nil
+}
+
+func (c *conn) LocalAddr() net.Addr {
+	return c.localAddr
+}
+
+func (c *conn) RemoteAddr() net.Addr {
+	return c.remoteAddr
+}
+
+func (c *conn) SetDeadline(t time.Time) error {
+	return &net.OpError{Op: "set", Net: "grpc", Source: nil, Addr: nil, Err: errors.New("deadline not supported")}
+}
+
+func (c *conn) SetReadDeadline(t time.Time) error {
+	return &net.OpError{Op: "set", Net: "grpc", Source: nil, Addr: nil, Err: errors.New("deadline not supported")}
+}
+
+func (c *conn) SetWriteDeadline(t time.Time) error {
+	return &net.OpError{Op: "set", Net: "grpc", Source: nil, Addr: nil, Err: errors.New("deadline not supported")}
+}

pkg/dialer/grpc/dialer.go

@@ -0,0 +1,140 @@
+package grpc
+
+import (
+	"context"
+	"net"
+	"sync"
+	"time"
+
+	pb "github.com/go-gost/gost/pkg/common/util/grpc/proto"
+	"github.com/go-gost/gost/pkg/dialer"
+	"github.com/go-gost/gost/pkg/logger"
+	md "github.com/go-gost/gost/pkg/metadata"
+	"github.com/go-gost/gost/pkg/registry"
+	"google.golang.org/grpc"
+	"google.golang.org/grpc/backoff"
+	"google.golang.org/grpc/credentials"
+	"google.golang.org/grpc/credentials/insecure"
+)
+
+func init() {
+	registry.RegisterDialer("grpc", NewDialer)
+}
+
+type grpcDialer struct {
+	clients     map[string]pb.GostTunelClient
+	clientMutex sync.Mutex
+	logger      logger.Logger
+	md          metadata
+	options     dialer.Options
+}
+
+func NewDialer(opts ...dialer.Option) dialer.Dialer {
+	options := dialer.Options{}
+	for _, opt := range opts {
+		opt(&options)
+	}
+
+	return &grpcDialer{
+		clients: make(map[string]pb.GostTunelClient),
+		logger:  options.Logger,
+		options: options,
+	}
+}
+
+func (d *grpcDialer) Init(md md.Metadata) (err error) {
+	return d.parseMetadata(md)
+}
+
+// Multiplex implements dialer.Multiplexer interface.
+func (d *grpcDialer) Multiplex() bool {
+	return true
+}
+
+func (d *grpcDialer) Dial(ctx context.Context, addr string, opts ...dialer.DialOption) (net.Conn, error) {
+	remoteAddr, err := net.ResolveTCPAddr("tcp", addr)
+	if err != nil {
+		return nil, err
+	}
+
+	d.clientMutex.Lock()
+	defer d.clientMutex.Unlock()
+
+	client, ok := d.clients[addr]
+	if !ok {
+		var options dialer.DialOptions
+		for _, opt := range opts {
+			opt(&options)
+		}
+
+		host := d.md.host
+		if host == "" {
+			host = options.Host
+		}
+
+		grpcOpts := []grpc.DialOption{
+			grpc.WithBlock(),
+			grpc.WithContextDialer(func(c context.Context, s string) (net.Conn, error) {
+				return d.dial(ctx, "tcp", s, &options)
+			}),
+			grpc.WithAuthority(host),
+			grpc.WithConnectParams(grpc.ConnectParams{
+				Backoff:           backoff.DefaultConfig,
+				MinConnectTimeout: 10 * time.Second,
+			}),
+		}
+		if !d.md.insecure {
+			grpcOpts = append(grpcOpts, grpc.WithTransportCredentials(credentials.NewTLS(d.options.TLSConfig)))
+		} else {
+			grpcOpts = append(grpcOpts, grpc.WithTransportCredentials(insecure.NewCredentials()))
+		}
+
+		cc, err := grpc.DialContext(ctx, addr, grpcOpts...)
+		if err != nil {
+			d.logger.Error(err)
+			return nil, err
+		}
+		client = pb.NewGostTunelClient(cc)
+		d.clients[addr] = client
+	}
+
+	cli, err := client.Tunnel(ctx)
+	if err != nil {
+		return nil, err
+	}
+
+	return &conn{
+		c:          cli,
+		localAddr:  &net.TCPAddr{},
+		remoteAddr: remoteAddr,
+		closed:     make(chan struct{}),
+	}, nil
+}
+
+func (d *grpcDialer) dial(ctx context.Context, network, addr string, opts *dialer.DialOptions) (net.Conn, error) {
+	dial := opts.DialFunc
+	if dial != nil {
+		conn, err := dial(ctx, addr)
+		if err != nil {
+			d.logger.Error(err)
+		} else {
+			d.logger.WithFields(map[string]interface{}{
+				"src": conn.LocalAddr().String(),
+				"dst": addr,
+			}).Debug("dial with dial func")
+		}
+		return conn, err
+	}
+
+	var netd net.Dialer
+	conn, err := netd.DialContext(ctx, network, addr)
+	if err != nil {
+		d.logger.Error(err)
+	} else {
+		d.logger.WithFields(map[string]interface{}{
+			"src": conn.LocalAddr().String(),
+			"dst": addr,
+		}).Debugf("dial direct %s/%s", addr, network)
+	}
+	return conn, err
+}

pkg/dialer/grpc/metadata.go

@@ -0,0 +1,22 @@
+package grpc
+
+import (
+	mdata "github.com/go-gost/gost/pkg/metadata"
+)
+
+type metadata struct {
+	insecure bool
+	host     string
+}
+
+func (d *grpcDialer) parseMetadata(md mdata.Metadata) (err error) {
+	const (
+		insecure = "grpcInsecure"
+		host     = "host"
+	)
+
+	d.md.insecure = mdata.GetBool(md, insecure)
+	d.md.host = mdata.GetString(md, host)
+
+	return
+}

pkg/dialer/http2/dialer.go

@@ -53,11 +53,6 @@ func (d *http2Dialer) Multiplex() bool {
 }
 
 func (d *http2Dialer) Dial(ctx context.Context, address string, opts ...dialer.DialOption) (net.Conn, error) {
-	options := &dialer.DialOptions{}
-	for _, opt := range opts {
-		opt(options)
-	}
-
 	raddr, err := net.ResolveTCPAddr("tcp", address)
 	if err != nil {
 		d.logger.Error(err)
@@ -69,11 +64,16 @@ func (d *http2Dialer) Dial(ctx context.Context, address string, opts ...dialer.D
 
 	client, ok := d.clients[address]
 	if !ok {
+		options := dialer.DialOptions{}
+		for _, opt := range opts {
+			opt(&options)
+		}
+
 		client = &http.Client{
 			Transport: &http.Transport{
 				TLSClientConfig: d.options.TLSConfig,
 				DialContext: func(ctx context.Context, network, addr string) (net.Conn, error) {
-					return d.dial(ctx, network, addr, options)
+					return d.dial(ctx, network, addr, &options)
 				},
 				ForceAttemptHTTP2:     true,
 				MaxIdleConns:          100,

pkg/dialer/option.go

@@ -36,11 +36,18 @@ func LoggerOption(logger logger.Logger) Option {
 }
 
 type DialOptions struct {
+	Host     string
 	DialFunc func(ctx context.Context, addr string) (net.Conn, error)
 }
 
 type DialOption func(opts *DialOptions)
 
+func HostDialOption(host string) DialOption {
+	return func(opts *DialOptions) {
+		opts.Host = host
+	}
+}
+
 func DialFuncDialOption(dialf func(ctx context.Context, addr string) (net.Conn, error)) DialOption {
 	return func(opts *DialOptions) {
 		opts.DialFunc = dialf

pkg/listener/grpc/listener.go

@@ -0,0 +1,101 @@
+package grpc
+
+import (
+	"net"
+
+	pb "github.com/go-gost/gost/pkg/common/util/grpc/proto"
+	"github.com/go-gost/gost/pkg/listener"
+	"github.com/go-gost/gost/pkg/logger"
+	md "github.com/go-gost/gost/pkg/metadata"
+	"github.com/go-gost/gost/pkg/registry"
+	"google.golang.org/grpc"
+	"google.golang.org/grpc/credentials"
+)
+
+func init() {
+	registry.RegisterListener("grpc", NewListener)
+}
+
+type grpcListener struct {
+	addr    net.Addr
+	server  *grpc.Server
+	cqueue  chan net.Conn
+	errChan chan error
+	md      metadata
+	logger  logger.Logger
+	options listener.Options
+}
+
+func NewListener(opts ...listener.Option) listener.Listener {
+	options := listener.Options{}
+	for _, opt := range opts {
+		opt(&options)
+	}
+	return &grpcListener{
+		logger:  options.Logger,
+		options: options,
+	}
+}
+
+func (l *grpcListener) Init(md md.Metadata) (err error) {
+	if err = l.parseMetadata(md); err != nil {
+		return
+	}
+
+	laddr, err := net.ResolveTCPAddr("tcp", l.options.Addr)
+	if err != nil {
+		return
+	}
+
+	ln, err := net.ListenTCP("tcp", laddr)
+	if err != nil {
+		return
+	}
+
+	var opts []grpc.ServerOption
+	if !l.md.insecure {
+		opts = append(opts, grpc.Creds(credentials.NewTLS(l.options.TLSConfig)))
+	}
+
+	l.server = grpc.NewServer(opts...)
+	l.addr = ln.Addr()
+	l.cqueue = make(chan net.Conn, l.md.backlog)
+	l.errChan = make(chan error, 1)
+
+	pb.RegisterGostTunelServer(l.server, &server{
+		cqueue:    l.cqueue,
+		localAddr: l.addr,
+		logger:    l.options.Logger,
+	})
+
+	go func() {
+		err := l.server.Serve(ln)
+		if err != nil {
+			l.errChan <- err
+		}
+		close(l.errChan)
+	}()
+
+	return
+}
+
+func (l *grpcListener) Accept() (conn net.Conn, err error) {
+	var ok bool
+	select {
+	case conn = <-l.cqueue:
+	case err, ok = <-l.errChan:
+		if !ok {
+			err = listener.ErrClosed
+		}
+	}
+	return
+}
+
+func (l *grpcListener) Close() error {
+	l.server.Stop()
+	return nil
+}
+
+func (l *grpcListener) Addr() net.Addr {
+	return l.addr
+}

pkg/listener/grpc/metadata.go

@@ -0,0 +1,29 @@
+package grpc
+
+import (
+	mdata "github.com/go-gost/gost/pkg/metadata"
+)
+
+const (
+	defaultBacklog = 128
+)
+
+type metadata struct {
+	backlog  int
+	insecure bool
+}
+
+func (l *grpcListener) parseMetadata(md mdata.Metadata) (err error) {
+	const (
+		backlog  = "backlog"
+		insecure = "grpcInsecure"
+	)
+
+	l.md.backlog = mdata.GetInt(md, backlog)
+	if l.md.backlog <= 0 {
+		l.md.backlog = defaultBacklog
+	}
+
+	l.md.insecure = mdata.GetBool(md, insecure)
+	return
+}

pkg/listener/grpc/server.go

@@ -0,0 +1,120 @@
+package grpc
+
+import (
+	"errors"
+	"io"
+	"net"
+	"time"
+
+	pb "github.com/go-gost/gost/pkg/common/util/grpc/proto"
+	"github.com/go-gost/gost/pkg/logger"
+)
+
+type server struct {
+	cqueue    chan net.Conn
+	localAddr net.Addr
+	pb.UnimplementedGostTunelServer
+	logger logger.Logger
+}
+
+func (s *server) Tunnel(srv pb.GostTunel_TunnelServer) error {
+	c := &conn{
+		s:          srv,
+		localAddr:  s.localAddr,
+		remoteAddr: &net.TCPAddr{},
+		closed:     make(chan struct{}),
+	}
+
+	select {
+	case s.cqueue <- c:
+	default:
+		c.Close()
+		s.logger.Warnf("connection queue is full, client discarded")
+	}
+
+	<-c.closed
+
+	return nil
+}
+
+type conn struct {
+	s          pb.GostTunel_TunnelServer
+	rb         []byte
+	localAddr  net.Addr
+	remoteAddr net.Addr
+	closed     chan struct{}
+}
+
+func (c *conn) Read(b []byte) (n int, err error) {
+	select {
+	case <-c.s.Context().Done():
+		err = c.s.Context().Err()
+		return
+	case <-c.closed:
+		err = io.ErrClosedPipe
+		return
+	default:
+	}
+
+	if len(c.rb) == 0 {
+		chunk, err := c.s.Recv()
+		if err != nil {
+			return 0, err
+		}
+		c.rb = chunk.Data
+	}
+
+	n = copy(b, c.rb)
+	c.rb = c.rb[n:]
+	return
+}
+
+func (c *conn) Write(b []byte) (n int, err error) {
+	select {
+	case <-c.s.Context().Done():
+		err = c.s.Context().Err()
+		return
+	case <-c.closed:
+		err = io.ErrClosedPipe
+		return
+	default:
+	}
+
+	if err = c.s.Send(&pb.Chunk{
+		Data: b,
+	}); err != nil {
+		return
+	}
+	n = len(b)
+	return
+}
+
+func (c *conn) Close() error {
+	select {
+	case <-c.closed:
+	default:
+		close(c.closed)
+	}
+
+	return nil
+}
+
+func (c *conn) LocalAddr() net.Addr {
+	return c.localAddr
+}
+
+func (c *conn) RemoteAddr() net.Addr {
+	return c.remoteAddr
+}
+
+func (c *conn) SetDeadline(t time.Time) error {
+	return &net.OpError{Op: "set", Net: "grpc", Source: nil, Addr: nil, Err: errors.New("deadline not supported")}
+}
+
+func (c *conn) SetReadDeadline(t time.Time) error {
+	return &net.OpError{Op: "set", Net: "grpc", Source: nil, Addr: nil, Err: errors.New("deadline not supported")}
+}
+
+func (c *conn) SetWriteDeadline(t time.Time) error {
+	return &net.OpError{Op: "set", Net: "grpc", Source: nil, Addr: nil, Err: errors.New("deadline not supported")}
+}

pkg/listener/tcp/listener.go

@@ -14,20 +14,20 @@ func init() {
 }
 
 type tcpListener struct {
-	addr string
-	md   metadata
 	net.Listener
-	logger logger.Logger
+	logger  logger.Logger
+	md      metadata
+	options listener.Options
 }
 
 func NewListener(opts ...listener.Option) listener.Listener {
-	options := &listener.Options{}
+	options := listener.Options{}
 	for _, opt := range opts {
-		opt(options)
+		opt(&options)
 	}
 	return &tcpListener{
-		addr:   options.Addr,
-		logger: options.Logger,
+		logger:  options.Logger,
+		options: options,
 	}
 }
 
@@ -36,7 +36,7 @@ func (l *tcpListener) Init(md md.Metadata) (err error) {
 		return
 	}
 
-	laddr, err := net.ResolveTCPAddr("tcp", l.addr)
+	laddr, err := net.ResolveTCPAddr("tcp", l.options.Addr)
 	if err != nil {
 		return
 	}