Add ping client

ping/socket_windows.go

@@ -0,0 +1,38 @@
+package ping
+
+import (
+	"net"
+	"net/netip"
+	"syscall"
+
+	"github.com/sagernet/sing/common/control"
+
+	"golang.org/x/sys/windows"
+)
+
+func connect(privileged bool, controlFunc control.Func, destination netip.Addr) (net.Conn, error) {
+	var dialer net.Dialer
+	dialer.Control = controlFunc
+	if destination.Is6() {
+		dialer.Control = control.Append(dialer.Control, func(network, address string, conn syscall.RawConn) error {
+			return control.Raw(conn, func(fd uintptr) error {
+				err := windows.SetsockoptInt(windows.Handle(fd), windows.IPPROTO_IPV6, IPV6_HOPLIMIT, 1)
+				if err != nil {
+					return err
+				}
+				err = windows.SetsockoptInt(windows.Handle(fd), windows.IPPROTO_IPV6, IPV6_RECVTCLASS, 1)
+				if err != nil {
+					return err
+				}
+				return nil
+			})
+		})
+	}
+	var network string
+	if destination.Is4() {
+		network = "ip4:icmp"
+	} else {
+		network = "ip6:ipv6-icmp"
+	}
+	return dialer.Dial(network, destination.String())
+}