1 files changed, 26 insertions, 0 deletions
diff --git a/tunnel/winipcfg/utils.go b/tunnel/winipcfg/utils.go
new file mode 100644
index 00000000..c841c40c
--- /dev/null
+++ b/tunnel/winipcfg/utils.go
@@ -0,0 +1,26 @@
+/* SPDX-License-Identifier: MIT
+ *
+ * Copyright (C) 2019 WireGuard LLC. All Rights Reserved.
+ */
+
+package winipcfg
+
+import (
+	"net"
+	"unsafe"
+
+	"golang.org/x/sys/windows"
+)
+
+// SocketAddressToIP function returns IPv4 or IPv6 address from windows.SocketAddress.
+// If the address is neither IPv4 not IPv6 nil is returned.
+//TODO: Remove once https://go-review.googlesource.com/c/sys/+/178577 is merged.
+func SocketAddressToIP(addr *windows.SocketAddress) net.IP {
+	if uintptr(addr.SockaddrLength) >= unsafe.Sizeof(windows.RawSockaddrInet4{}) && addr.Sockaddr.Addr.Family == windows.AF_INET {
+		return (*windows.RawSockaddrInet4)(unsafe.Pointer(addr.Sockaddr)).Addr[:]
+	} else if uintptr(addr.SockaddrLength) >= unsafe.Sizeof(windows.RawSockaddrInet6{}) && addr.Sockaddr.Addr.Family == windows.AF_INET6 {
+		return (*windows.RawSockaddrInet6)(unsafe.Pointer(addr.Sockaddr)).Addr[:]
+	} else {
+		return nil
+	}
+}