Add tun inbound for windows

common/dialer/auto_other.go

@@ -1,4 +1,4 @@
-//go:build !linux
+//go:build !linux && !windows
 
 package dialer
 

common/dialer/auto_windows.go

@@ -0,0 +1,68 @@
+package dialer
+
+import (
+	"encoding/binary"
+	"net"
+	"net/netip"
+	"syscall"
+	"unsafe"
+
+	"github.com/sagernet/sing-box/adapter"
+	"github.com/sagernet/sing/common/control"
+	E "github.com/sagernet/sing/common/exceptions"
+
+	"golang.org/x/sys/windows"
+)
+
+const (
+	IP_UNICAST_IF   = 31
+	IPV6_UNICAST_IF = 31
+)
+
+func bind4(handle windows.Handle, ifaceIdx int) error {
+	var bytes [4]byte
+	binary.BigEndian.PutUint32(bytes[:], uint32(ifaceIdx))
+	idx := *(*uint32)(unsafe.Pointer(&bytes[0]))
+	return windows.SetsockoptInt(handle, windows.IPPROTO_IP, IP_UNICAST_IF, int(idx))
+}
+
+func bind6(handle windows.Handle, ifaceIdx int) error {
+	return windows.SetsockoptInt(handle, windows.IPPROTO_IPV6, IPV6_UNICAST_IF, int(ifaceIdx))
+}
+
+func BindToInterface(router adapter.Router) control.Func {
+	return func(network, address string, conn syscall.RawConn) error {
+		interfaceName := router.DefaultInterfaceName()
+		if interfaceName == "" {
+			return nil
+		}
+		ipStr, _, err := net.SplitHostPort(address)
+		if err == nil {
+			if ip, err := netip.ParseAddr(ipStr); err == nil && !ip.IsGlobalUnicast() {
+				return err
+			}
+		}
+		var innerErr error
+		err = conn.Control(func(fd uintptr) {
+			handle := windows.Handle(fd)
+			// handle ip empty, e.g. net.Listen("udp", ":0")
+			if ipStr == "" {
+				innerErr = bind4(handle, router.DefaultInterfaceIndex())
+				if innerErr != nil {
+					return
+				}
+				// try bind ipv6, if failed, ignore. it's a workaround for windows disable interface ipv6
+				bind6(handle, router.DefaultInterfaceIndex())
+				return
+			}
+
+			switch network {
+			case "tcp4", "udp4", "ip4":
+				innerErr = bind4(handle, router.DefaultInterfaceIndex())
+			case "tcp6", "udp6":
+				innerErr = bind6(handle, router.DefaultInterfaceIndex())
+			}
+		})
+		return E.Errors(innerErr, err)
+	}
+}

common/iffmonitor/monitor.go

@@ -1,9 +0,0 @@
-package iffmonitor
-
-import "github.com/sagernet/sing-box/adapter"
-
-type InterfaceMonitor interface {
-	adapter.Service
-	DefaultInterfaceName() string
-	DefaultInterfaceIndex() int
-}

common/iffmonitor/monitor_linux.go

@@ -1,108 +0,0 @@
-package iffmonitor
-
-import (
-	"os"
-
-	"github.com/sagernet/sing-box/log"
-	E "github.com/sagernet/sing/common/exceptions"
-
-	"github.com/vishvananda/netlink"
-)
-
-var _ InterfaceMonitor = (*monitor)(nil)
-
-type monitor struct {
-	logger                log.Logger
-	defaultInterfaceName  string
-	defaultInterfaceIndex int
-	update                chan netlink.RouteUpdate
-	close                 chan struct{}
-}
-
-func New(logger log.Logger) (InterfaceMonitor, error) {
-	return &monitor{
-		logger: logger,
-		update: make(chan netlink.RouteUpdate, 2),
-		close:  make(chan struct{}),
-	}, nil
-}
-
-func (m *monitor) Start() error {
-	err := netlink.RouteSubscribe(m.update, m.close)
-	if err != nil {
-		return err
-	}
-	err = m.checkUpdate()
-	if err != nil {
-		return err
-	}
-	go m.loopUpdate()
-	return nil
-}
-
-func (m *monitor) loopUpdate() {
-	for {
-		select {
-		case <-m.close:
-			return
-		case <-m.update:
-			err := m.checkUpdate()
-			if err != nil {
-				m.logger.Error(E.Cause(err, "check default interface"))
-			}
-		}
-	}
-}
-
-func (m *monitor) checkUpdate() error {
-	routes, err := netlink.RouteList(nil, netlink.FAMILY_V4)
-	if err != nil {
-		return err
-	}
-	for _, route := range routes {
-		if route.Dst != nil {
-			continue
-		}
-		var link netlink.Link
-		link, err = netlink.LinkByIndex(route.LinkIndex)
-		if err != nil {
-			return err
-		}
-
-		if link.Type() == "tuntap" {
-			continue
-		}
-
-		oldInterface := m.defaultInterfaceName
-		oldIndex := m.defaultInterfaceIndex
-
-		m.defaultInterfaceName = link.Attrs().Name
-		m.defaultInterfaceIndex = link.Attrs().Index
-
-		if oldInterface == m.defaultInterfaceName && oldIndex == m.defaultInterfaceIndex {
-			return nil
-		}
-
-		m.logger.Info("updated default interface ", m.defaultInterfaceName, ", index ", m.defaultInterfaceIndex)
-		return nil
-	}
-	return E.New("no route to internet")
-}
-
-func (m *monitor) Close() error {
-	select {
-	case <-m.close:
-		return os.ErrClosed
-	default:
-	}
-	close(m.close)
-	return nil
-}
-
-func (m *monitor) DefaultInterfaceName() string {
-	return m.defaultInterfaceName
-}
-
-func (m *monitor) DefaultInterfaceIndex() int {
-	return m.defaultInterfaceIndex
-}

common/iffmonitor/monitor_other.go

@@ -1,13 +0,0 @@
-//go:build !linux
-
-package iffmonitor
-
-import (
-	"os"
-
-	"github.com/sagernet/sing-box/log"
-)
-
-func New(logger log.Logger) (InterfaceMonitor, error) {
-	return nil, os.ErrInvalid
-}