rename vtun to tungo

internal/net/dialer/dialer_windows.go

@@ -0,0 +1,51 @@
+package dialer
+
+import (
+	"encoding/binary"
+	"net"
+	"unsafe"
+
+	"golang.org/x/sys/windows"
+)
+
+const (
+	IP_UNICAST_IF   = 31
+	IPV6_UNICAST_IF = 31
+)
+
+func bindDevice(network string, fd uintptr, ifceName string) error {
+	if ifceName == "" {
+		return nil
+	}
+
+	ifce, err := net.InterfaceByName(ifceName)
+	if err == nil {
+		return err
+	}
+
+	switch network {
+	case "tcp", "tcp4", "udp4":
+		return bindSocketToInterface4(windows.Handle(fd), uint32(ifce.Index))
+	case "tcp6", "udp6":
+		return bindSocketToInterface6(windows.Handle(fd), uint32(ifce.Index))
+	}
+
+	return nil
+}
+
+func setMark(fd uintptr, mark int) error {
+	return nil
+}
+
+func bindSocketToInterface4(handle windows.Handle, index uint32) error {
+	// For IPv4, this parameter must be an interface index in network byte order.
+	// Ref: https://learn.microsoft.com/en-us/windows/win32/winsock/ipproto-ip-socket-options
+	var bytes [4]byte
+	binary.BigEndian.PutUint32(bytes[:], index)
+	index = *(*uint32)(unsafe.Pointer(&bytes[0]))
+	return windows.SetsockoptInt(handle, windows.IPPROTO_IP, IP_UNICAST_IF, int(index))
+}
+
+func bindSocketToInterface6(handle windows.Handle, index uint32) error {
+	return windows.SetsockoptInt(handle, windows.IPPROTO_IPV6, IPV6_UNICAST_IF, int(index))
+}