Improve: use interface index for macos

common/singledo/singledo.go

@@ -1,66 +0,0 @@
-package singledo
-
-// Ref: github.com/Dreamacro/clash/common/singledo
-
-import (
-	"sync"
-	"time"
-)
-
-type call struct {
-	wg  sync.WaitGroup
-	val any
-	err error
-}
-
-type Single struct {
-	mux    sync.Mutex
-	last   time.Time
-	wait   time.Duration
-	call   *call
-	result *Result
-}
-
-type Result struct {
-	Val any
-	Err error
-}
-
-// Do single.Do likes sync.singleFlight
-//lint:ignore ST1008 it likes sync.singleFlight
-func (s *Single) Do(fn func() (any, error)) (v any, err error, shared bool) {
-	s.mux.Lock()
-	now := time.Now()
-	if now.Before(s.last.Add(s.wait)) {
-		s.mux.Unlock()
-		return s.result.Val, s.result.Err, true
-	}
-
-	if call := s.call; call != nil {
-		s.mux.Unlock()
-		call.wg.Wait()
-		return call.val, call.err, true
-	}
-
-	call := &call{}
-	call.wg.Add(1)
-	s.call = call
-	s.mux.Unlock()
-	call.val, call.err = fn()
-	call.wg.Done()
-
-	s.mux.Lock()
-	s.call = nil
-	s.result = &Result{call.val, call.err}
-	s.last = now
-	s.mux.Unlock()
-	return call.val, call.err, false
-}
-
-func (s *Single) Reset() {
-	s.last = time.Time{}
-}
-
-func NewSingle(wait time.Duration) *Single {
-	return &Single{wait: wait}
-}

common/singledo/singledo_test.go

@@ -1,69 +0,0 @@
-package singledo
-
-import (
-	"sync"
-	"testing"
-	"time"
-
-	"github.com/stretchr/testify/assert"
-	"go.uber.org/atomic"
-)
-
-func TestBasic(t *testing.T) {
-	single := NewSingle(time.Millisecond * 30)
-	foo := 0
-	shardCount := atomic.NewInt32(0)
-	call := func() (any, error) {
-		foo++
-		time.Sleep(time.Millisecond * 5)
-		return nil, nil
-	}
-
-	var wg sync.WaitGroup
-	const n = 5
-	wg.Add(n)
-	for i := 0; i < n; i++ {
-		go func() {
-			_, _, shard := single.Do(call)
-			if shard {
-				shardCount.Inc()
-			}
-			wg.Done()
-		}()
-	}
-
-	wg.Wait()
-	assert.Equal(t, 1, foo)
-	assert.Equal(t, int32(4), shardCount.Load())
-}
-
-func TestTimer(t *testing.T) {
-	single := NewSingle(time.Millisecond * 30)
-	foo := 0
-	call := func() (any, error) {
-		foo++
-		return nil, nil
-	}
-
-	single.Do(call)
-	time.Sleep(10 * time.Millisecond)
-	_, _, shard := single.Do(call)
-
-	assert.Equal(t, 1, foo)
-	assert.True(t, shard)
-}
-
-func TestReset(t *testing.T) {
-	single := NewSingle(time.Millisecond * 30)
-	foo := 0
-	call := func() (any, error) {
-		foo++
-		return nil, nil
-	}
-
-	single.Do(call)
-	single.Reset()
-	single.Do(call)
-
-	assert.Equal(t, 2, foo)
-}

component/dialer/dialer.go

@@ -9,8 +9,9 @@ import (
 )
 
 var (
-	DefaultInterfaceName = atomic.NewString("")
+	DefaultInterfaceName  = atomic.NewString("")
-	DefaultRoutingMark   = atomic.NewInt32(0)
+	DefaultInterfaceIndex = atomic.NewInt32(0)
+	DefaultRoutingMark    = atomic.NewInt32(0)
 )
 
 type Options struct {
@@ -19,6 +20,11 @@ type Options struct {
 	// from that particular interface are processed by the socket.
 	InterfaceName string
 
+	// InterfaceIndex is the index of interface/device to bind.
+	// It is almost the same as InterfaceName except it uses the
+	// index of the interface instead of the name.
+	InterfaceIndex int
+
 	// RoutingMark is the mark for each packet sent through this
 	// socket. Changing the mark can be used for mark-based routing
 	// without netfilter or for packet filtering.
@@ -27,8 +33,9 @@ type Options struct {
 
 func DialContext(ctx context.Context, network, address string) (net.Conn, error) {
 	return DialContextWithOptions(ctx, network, address, &Options{
-		InterfaceName: DefaultInterfaceName.Load(),
+		InterfaceName:  DefaultInterfaceName.Load(),
-		RoutingMark:   int(DefaultRoutingMark.Load()),
+		InterfaceIndex: int(DefaultInterfaceIndex.Load()),
+		RoutingMark:    int(DefaultRoutingMark.Load()),
 	})
 }
 
@@ -43,8 +50,9 @@ func DialContextWithOptions(ctx context.Context, network, address string, opts *
 
 func ListenPacket(network, address string) (net.PacketConn, error) {
 	return ListenPacketWithOptions(network, address, &Options{
-		InterfaceName: DefaultInterfaceName.Load(),
+		InterfaceName:  DefaultInterfaceName.Load(),
-		RoutingMark:   int(DefaultRoutingMark.Load()),
+		InterfaceIndex: int(DefaultInterfaceIndex.Load()),
+		RoutingMark:    int(DefaultRoutingMark.Load()),
 	})
 }
 

component/dialer/sockopt_darwin.go

@@ -3,25 +3,10 @@ package dialer
 import (
 	"net"
 	"syscall"
-	"time"
-
-	"github.com/xjasonlyu/tun2socks/v2/common/singledo"
 
 	"golang.org/x/sys/unix"
 )
 
-var interfaces = singledo.NewSingle(30 * time.Second)
-
-func resolveInterfaceByName(name string) (*net.Interface, error) {
-	value, err, _ := interfaces.Do(func() (any, error) {
-		return net.InterfaceByName(name)
-	})
-	if err != nil {
-		return nil, err
-	}
-	return value.(*net.Interface), nil
-}
-
 func setSocketOptions(network, address string, c syscall.RawConn, opts *Options) (err error) {
 	if opts == nil || !isTCPSocket(network) && !isUDPSocket(network) {
 		return
@@ -29,24 +14,23 @@ func setSocketOptions(network, address string, c syscall.RawConn, opts *Options)
 
 	var innerErr error
 	err = c.Control(func(fd uintptr) {
-		// must be GlobalUnicast.
 		host, _, _ := net.SplitHostPort(address)
 		if ip := net.ParseIP(host); ip != nil && !ip.IsGlobalUnicast() {
 			return
 		}
 
-		if opts.InterfaceName != "" {
+		if opts.InterfaceIndex == 0 && opts.InterfaceName != "" {
-			var iface *net.Interface
+			if iface, err := net.InterfaceByName(opts.InterfaceName); err == nil {
-			iface, innerErr = resolveInterfaceByName(opts.InterfaceName)
+				opts.InterfaceIndex = iface.Index
-			if innerErr != nil {
-				return
 			}
+		}
 
+		if opts.InterfaceIndex != 0 {
 			switch network {
 			case "tcp4", "udp4":
-				innerErr = unix.SetsockoptInt(int(fd), syscall.IPPROTO_IP, syscall.IP_BOUND_IF, iface.Index)
+				innerErr = unix.SetsockoptInt(int(fd), syscall.IPPROTO_IP, syscall.IP_BOUND_IF, opts.InterfaceIndex)
 			case "tcp6", "udp6":
-				innerErr = unix.SetsockoptInt(int(fd), syscall.IPPROTO_IPV6, syscall.IPV6_BOUND_IF, iface.Index)
+				innerErr = unix.SetsockoptInt(int(fd), syscall.IPPROTO_IPV6, syscall.IPV6_BOUND_IF, opts.InterfaceIndex)
 			}
 			if innerErr != nil {
 				return

component/dialer/sockopt_linux.go

@@ -14,12 +14,17 @@ func setSocketOptions(network, address string, c syscall.RawConn, opts *Options)
 
 	var innerErr error
 	err = c.Control(func(fd uintptr) {
-		// must be GlobalUnicast.
 		host, _, _ := net.SplitHostPort(address)
 		if ip := net.ParseIP(host); ip != nil && !ip.IsGlobalUnicast() {
 			return
 		}
 
+		if opts.InterfaceName == "" && opts.InterfaceIndex != 0 {
+			if iface, err := net.InterfaceByIndex(opts.InterfaceIndex); err == nil {
+				opts.InterfaceName = iface.Name
+			}
+		}
+
 		if opts.InterfaceName != "" {
 			if innerErr = unix.BindToDevice(int(fd), opts.InterfaceName); innerErr != nil {
 				return

engine/engine.go

@@ -3,6 +3,7 @@ package engine
 import (
 	"errors"
 	"fmt"
+	"net"
 	"sync"
 
 	"github.com/xjasonlyu/tun2socks/v2/component/dialer"
@@ -97,7 +98,12 @@ func general(k *Key) error {
 	log.SetLevel(level)
 
 	if k.Interface != "" {
-		dialer.DefaultInterfaceName.Store(k.Interface)
+		iface, err := net.InterfaceByName(k.Interface)
+		if err != nil {
+			return err
+		}
+		dialer.DefaultInterfaceName.Store(iface.Name)
+		dialer.DefaultInterfaceIndex.Store(int32(iface.Index))
 		log.Infof("[DIALER] bind to interface: %s", k.Interface)
 	}