From 1f146a5e7ad9081c79026339c2ad82f357743d66 Mon Sep 17 00:00:00 2001
From: "Jason A. Donenfeld" <Jason@zx2c4.com>
Date: Tue, 8 Oct 2019 09:58:58 +0200
Subject: [PATCH] wintun: expose version

---
 tun/tun_windows.go           |  5 +++++
 tun/wintun/wintun_windows.go | 30 +++++++++++++++++++++++++++++-
 2 files changed, 34 insertions(+), 1 deletion(-)

diff --git a/tun/tun_windows.go b/tun/tun_windows.go
index 6a603a3..4b5da02 100644
--- a/tun/tun_windows.go
+++ b/tun/tun_windows.go
@@ -244,6 +244,11 @@ func (tun *NativeTun) LUID() uint64 {
 	return tun.wt.LUID()
 }
 
+// Version returns the version of the Wintun driver and NDIS system currently loaded.
+func (tun *NativeTun) Version() (driverVersion string, ndisVersion string, err error) {
+	return tun.wt.Version()
+}
+
 func (rate *rateJuggler) update(packetLen uint64) {
 	now := nanotime()
 	total := atomic.AddUint64(&rate.nextByteCount, packetLen)
diff --git a/tun/wintun/wintun_windows.go b/tun/wintun/wintun_windows.go
index e2348c0..e6dc141 100644
--- a/tun/wintun/wintun_windows.go
+++ b/tun/wintun/wintun_windows.go
@@ -671,11 +671,39 @@ func (wintun *Interface) tcpipAdapterRegKeyName() string {
 	return fmt.Sprintf("SYSTEM\\CurrentControlSet\\Services\\Tcpip\\Parameters\\Adapters\\%v", wintun.cfgInstanceID)
 }
 
-// deviceRegKeyName returns the device-level registry key name
+// deviceRegKeyName returns the device-level registry key name.
 func (wintun *Interface) deviceRegKeyName() string {
 	return fmt.Sprintf("SYSTEM\\CurrentControlSet\\Enum\\%v", wintun.devInstanceID)
 }
 
+// Version returns the version of the Wintun driver and NDIS system currently loaded.
+func (wintun *Interface) Version() (driverVersion string, ndisVersion string, err error) {
+	key, err := registry.OpenKey(registry.LOCAL_MACHINE, "SYSTEM\\CurrentControlSet\\Services\\Wintun", registry.QUERY_VALUE)
+	if err != nil {
+		return
+	}
+	defer key.Close()
+	driverMajor, _, err := key.GetIntegerValue("DriverMajorVersion")
+	if err != nil {
+		return
+	}
+	driverMinor, _, err := key.GetIntegerValue("DriverMinorVersion")
+	if err != nil {
+		return
+	}
+	ndisMajor, _, err := key.GetIntegerValue("NdisMajorVersion")
+	if err != nil {
+		return
+	}
+	ndisMinor, _, err := key.GetIntegerValue("NdisMinorVersion")
+	if err != nil {
+		return
+	}
+	driverVersion = fmt.Sprintf("%d.%d", driverMajor, driverMinor)
+	ndisVersion = fmt.Sprintf("%d.%d", ndisMajor, ndisMinor)
+	return
+}
+
 // tcpipInterfaceRegKeyName returns the interface-specific TCP/IP network registry key name.
 func (wintun *Interface) tcpipInterfaceRegKeyName() (path string, err error) {
 	key, err := registry.OpenKey(registry.LOCAL_MACHINE, wintun.tcpipAdapterRegKeyName(), registry.QUERY_VALUE)