feat: socket options

app/tun/config.pb.go

@@ -9,6 +9,7 @@ package tun
 import (
 	routercommon "github.com/v2fly/v2ray-core/v5/app/router/routercommon"
 	_ "github.com/v2fly/v2ray-core/v5/common/protoext"
+	internet "github.com/v2fly/v2ray-core/v5/transport/internet"
 	protoreflect "google.golang.org/protobuf/reflect/protoreflect"
 	protoimpl "google.golang.org/protobuf/runtime/protoimpl"
 	reflect "reflect"
@@ -27,14 +28,15 @@ type Config struct {
 	sizeCache     protoimpl.SizeCache
 	unknownFields protoimpl.UnknownFields
 
-	Name                  string               `protobuf:"bytes,1,opt,name=name,proto3" json:"name,omitempty"`
-	Mtu                   uint32               `protobuf:"varint,2,opt,name=mtu,proto3" json:"mtu,omitempty"`
-	UserLevel             uint32               `protobuf:"varint,3,opt,name=user_level,json=userLevel,proto3" json:"user_level,omitempty"`
-	Tag                   string               `protobuf:"bytes,5,opt,name=tag,proto3" json:"tag,omitempty"`
-	Ips                   []*routercommon.CIDR `protobuf:"bytes,6,rep,name=ips,proto3" json:"ips,omitempty"`
-	Routes                []*routercommon.CIDR `protobuf:"bytes,7,rep,name=routes,proto3" json:"routes,omitempty"`
-	EnablePromiscuousMode bool                 `protobuf:"varint,8,opt,name=enable_promiscuous_mode,json=enablePromiscuousMode,proto3" json:"enable_promiscuous_mode,omitempty"`
-	EnableSpoofing        bool                 `protobuf:"varint,9,opt,name=enable_spoofing,json=enableSpoofing,proto3" json:"enable_spoofing,omitempty"`
+	Name                  string                 `protobuf:"bytes,1,opt,name=name,proto3" json:"name,omitempty"`
+	Mtu                   uint32                 `protobuf:"varint,2,opt,name=mtu,proto3" json:"mtu,omitempty"`
+	UserLevel             uint32                 `protobuf:"varint,3,opt,name=user_level,json=userLevel,proto3" json:"user_level,omitempty"`
+	Tag                   string                 `protobuf:"bytes,5,opt,name=tag,proto3" json:"tag,omitempty"`
+	Ips                   []*routercommon.CIDR   `protobuf:"bytes,6,rep,name=ips,proto3" json:"ips,omitempty"`
+	Routes                []*routercommon.CIDR   `protobuf:"bytes,7,rep,name=routes,proto3" json:"routes,omitempty"`
+	EnablePromiscuousMode bool                   `protobuf:"varint,8,opt,name=enable_promiscuous_mode,json=enablePromiscuousMode,proto3" json:"enable_promiscuous_mode,omitempty"`
+	EnableSpoofing        bool                   `protobuf:"varint,9,opt,name=enable_spoofing,json=enableSpoofing,proto3" json:"enable_spoofing,omitempty"`
+	SocketSettings        *internet.SocketConfig `protobuf:"bytes,10,opt,name=socket_settings,json=socketSettings,proto3" json:"socket_settings,omitempty"`
 }
 
 func (x *Config) Reset() {
@@ -125,6 +127,13 @@ func (x *Config) GetEnableSpoofing() bool {
 	return false
 }
 
+func (x *Config) GetSocketSettings() *internet.SocketConfig {
+	if x != nil {
+		return x.SocketSettings
+	}
+	return nil
+}
+
 var File_app_tun_config_proto protoreflect.FileDescriptor
 
 var file_app_tun_config_proto_rawDesc = []byte{
@@ -135,34 +144,42 @@ var file_app_tun_config_proto_rawDesc = []byte{
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+	0x72, 0x6f, 0x74, 0x6f, 0x33,
 }
 
 var (
@@ -179,17 +196,19 @@ func file_app_tun_config_proto_rawDescGZIP() []byte {
 
 var file_app_tun_config_proto_msgTypes = make([]protoimpl.MessageInfo, 1)
 var file_app_tun_config_proto_goTypes = []interface{}{
-	(*Config)(nil),            // 0: v2ray.core.app.tun.Config
-	(*routercommon.CIDR)(nil), // 1: v2ray.core.app.router.routercommon.CIDR
+	(*Config)(nil),                // 0: v2ray.core.app.tun.Config
+	(*routercommon.CIDR)(nil),     // 1: v2ray.core.app.router.routercommon.CIDR
+	(*internet.SocketConfig)(nil), // 2: v2ray.core.transport.internet.SocketConfig
 }
 var file_app_tun_config_proto_depIdxs = []int32{
 	1, // 0: v2ray.core.app.tun.Config.ips:type_name -> v2ray.core.app.router.routercommon.CIDR
 	1, // 1: v2ray.core.app.tun.Config.routes:type_name -> v2ray.core.app.router.routercommon.CIDR
-	2, // [2:2] is the sub-list for method output_type
-	2, // [2:2] is the sub-list for method input_type
-	2, // [2:2] is the sub-list for extension type_name
-	2, // [2:2] is the sub-list for extension extendee
-	0, // [0:2] is the sub-list for field type_name
+	2, // 2: v2ray.core.app.tun.Config.socket_settings:type_name -> v2ray.core.transport.internet.SocketConfig
+	3, // [3:3] is the sub-list for method output_type
+	3, // [3:3] is the sub-list for method input_type
+	3, // [3:3] is the sub-list for extension type_name
+	3, // [3:3] is the sub-list for extension extendee
+	0, // [0:3] is the sub-list for field type_name
 }
 
 func init() { file_app_tun_config_proto_init() }

app/tun/config.proto

@@ -9,6 +9,7 @@ option java_multiple_files = true;
 
 import "app/router/routercommon/common.proto";
 import "common/protoext/extensions.proto";
+import "transport/internet/config.proto";
 
 message Config {
     option (v2ray.core.common.protoext.message_opt).type = "service";
@@ -18,10 +19,11 @@ message Config {
     string name = 1;
     uint32 mtu = 2;
     uint32 user_level = 3;
-    reserved 4;
+    reserved 4; // Reserved for PacketEncode
     string tag = 5;
     repeated v2ray.core.app.router.routercommon.CIDR ips = 6;
     repeated v2ray.core.app.router.routercommon.CIDR routes = 7;
     bool enable_promiscuous_mode = 8;
     bool enable_spoofing = 9;
+    v2ray.core.transport.internet.SocketConfig socket_settings = 10;
 }

app/tun/handler_tcp.go

@@ -2,6 +2,7 @@ package tun
 
 import (
 	"context"
+	"time"
 
 	tun_net "github.com/v2fly/v2ray-core/v5/app/tun/net"
 	"github.com/v2fly/v2ray-core/v5/common"
@@ -13,7 +14,10 @@ import (
 	"github.com/v2fly/v2ray-core/v5/common/task"
 	"github.com/v2fly/v2ray-core/v5/features/policy"
 	"github.com/v2fly/v2ray-core/v5/features/routing"
+	internet "github.com/v2fly/v2ray-core/v5/transport/internet"
+	"gvisor.dev/gvisor/pkg/tcpip"
 	"gvisor.dev/gvisor/pkg/tcpip/adapters/gonet"
+	"gvisor.dev/gvisor/pkg/tcpip/header"
 	"gvisor.dev/gvisor/pkg/tcpip/stack"
 	"gvisor.dev/gvisor/pkg/tcpip/transport/tcp"
 	"gvisor.dev/gvisor/pkg/waiter"
@@ -51,7 +55,9 @@ func SetTCPHandler(ctx context.Context, dispatcher routing.Dispatcher, policyMan
 			}
 			defer r.Complete(false)
 
-			// TODO: set sockopt
+			if err := applySocketOptions(s, linkedEndpoint, config.SocketSettings); err != nil {
+				newError("failed to apply socket options: ", err).WriteToLog(session.ExportIDToError(ctx))
+			}
 
 			conn := &tcpConn{
 				TCPConn: gonet.NewTCPConn(wg, linkedEndpoint),
@@ -124,3 +130,37 @@ func (h *TCPHandler) Handle(conn tun_net.TCPConn) error {
 
 	return nil
 }
+
+func applySocketOptions(s *stack.Stack, endpoint tcpip.Endpoint, config *internet.SocketConfig) tcpip.Error {
+	if config.TcpKeepAliveInterval > 0 {
+		interval := tcpip.KeepaliveIntervalOption(time.Duration(config.TcpKeepAliveInterval) * time.Second)
+		if err := endpoint.SetSockOpt(&interval); err != nil {
+			return err
+		}
+	}
+
+	if config.TcpKeepAliveIdle > 0 {
+		idle := tcpip.KeepaliveIdleOption(time.Duration(config.TcpKeepAliveIdle) * time.Second)
+		if err := endpoint.SetSockOpt(&idle); err != nil {
+			return err
+		}
+	}
+
+	if config.TcpKeepAliveInterval > 0 || config.TcpKeepAliveIdle > 0 {
+		endpoint.SocketOptions().SetKeepAlive(true)
+
+	}
+	{
+		var sendBufferSizeRangeOption tcpip.TCPSendBufferSizeRangeOption
+		if err := s.TransportProtocolOption(header.TCPProtocolNumber, &sendBufferSizeRangeOption); err == nil {
+			endpoint.SocketOptions().SetReceiveBufferSize(int64(sendBufferSizeRangeOption.Default), false)
+		}
+
+		var receiveBufferSizeRangeOption tcpip.TCPReceiveBufferSizeRangeOption
+		if err := s.TransportProtocolOption(header.TCPProtocolNumber, &receiveBufferSizeRangeOption); err == nil {
+			endpoint.SocketOptions().SetSendBufferSize(int64(receiveBufferSizeRangeOption.Default), false)
+		}
+	}
+
+	return nil
+}

app/tun/nic.go → app/tun/option.go

@@ -6,6 +6,7 @@ import (
 	"gvisor.dev/gvisor/pkg/tcpip/network/ipv4"
 	"gvisor.dev/gvisor/pkg/tcpip/network/ipv6"
 	"gvisor.dev/gvisor/pkg/tcpip/stack"
+	"gvisor.dev/gvisor/pkg/tcpip/transport/tcp"
 )
 
 func CreateNIC(id tcpip.NICID, linkEndpoint stack.LinkEndpoint) StackOption {
@@ -88,3 +89,23 @@ func SetRouteTable(id tcpip.NICID, routes []*routercommon.CIDR) StackOption {
 		return nil
 	}
 }
+
+func SetTCPSendBufferSize(size int) StackOption {
+	return func(s *stack.Stack) error {
+		sendBufferSizeRangeOption := tcpip.TCPSendBufferSizeRangeOption{Min: tcp.MinBufferSize, Default: size, Max: tcp.MaxBufferSize}
+		if err := s.SetTransportProtocolOption(tcp.ProtocolNumber, &sendBufferSizeRangeOption); err != nil {
+			return newError("failed to set tcp send buffer size:", err)
+		}
+		return nil
+	}
+}
+
+func SetTCPReceiveBufferSize(size int) StackOption {
+	return func(s *stack.Stack) error {
+		receiveBufferSizeRangeOption := tcpip.TCPReceiveBufferSizeRangeOption{Min: tcp.MinBufferSize, Default: size, Max: tcp.MaxBufferSize}
+		if err := s.SetTransportProtocolOption(tcp.ProtocolNumber, &receiveBufferSizeRangeOption); err != nil {
+			return newError("failed to set tcp receive buffer size:", err)
+		}
+		return nil
+	}
+}

app/tun/stack.go

@@ -39,6 +39,14 @@ func (t *TUN) CreateStack(linkedEndpoint stack.LinkEndpoint) (*stack.Stack, erro
 		SetSpoofing(nicID, t.config.EnableSpoofing),
 	}
 
+	if size := t.config.SocketSettings.TxBufSize; size != 0 {
+		opts = append(opts, SetTCPSendBufferSize(int(size)))
+	}
+
+	if size := t.config.SocketSettings.RxBufSize; size != 0 {
+		opts = append(opts, SetTCPReceiveBufferSize(int(size)))
+	}
+
 	for _, opt := range opts {
 		if err := opt(s); err != nil {
 			return nil, err