From 0c9a87b8a2fe977ea0082da05e5d0ef02196320a Mon Sep 17 00:00:00 2001
From: "Jason A. Donenfeld" <Jason@zx2c4.com>
Date: Wed, 5 May 2021 11:25:30 +0200
Subject: [PATCH] api: skip requested GUID if !win10

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
---
 api/adapter.c | 17 ++++++++++++-----
 1 file changed, 12 insertions(+), 5 deletions(-)

diff --git a/api/adapter.c b/api/adapter.c
index a85d17b..ba4467c 100644
--- a/api/adapter.c
+++ b/api/adapter.c
@@ -898,15 +898,19 @@ _Return_type_success_(return != INVALID_HANDLE_VALUE) HANDLE WINAPI
     return OpenDeviceObject(Adapter->DevInstanceID);
 }
 
+static BOOL
+IsWindows10(void)
+{
+    DWORD MajorVersion;
+    RtlGetNtVersionNumbers(&MajorVersion, NULL, NULL);
+    return MajorVersion >= 10;
+}
+
 static BOOL
 HaveWHQL(void)
 {
     if (HAVE_WHQL)
-    {
-        DWORD MajorVersion;
-        RtlGetNtVersionNumbers(&MajorVersion, NULL, NULL);
-        return MajorVersion >= 10;
-    }
+        return IsWindows10();
     return FALSE;
 }
 
@@ -1418,6 +1422,9 @@ static _Return_type_success_(return != NULL) WINTUN_ADAPTER *CreateAdapter(
 {
     LOG(WINTUN_LOG_INFO, L"Creating adapter");
 
+    if (!IsWindows10())
+        RequestedGUID = NULL;
+
     if (RequestedGUID)
     {
         WCHAR RegPath[MAX_REG_PATH];