From 59d3e370270e16f80bdad39d2739df1973a1ad82 Mon Sep 17 00:00:00 2001
From: Dimitri Papadopoulos
 <3350651-DimitriPapadopoulos@users.noreply.gitlab.com>
Date: Wed, 8 Dec 2021 09:21:06 +0100
Subject: [PATCH] Load wintun.dll from the application directory only

Do not attempt to load it from the System32 directory.

Different versions of `wintun.dll` or `wintun.sys` float around in system
directories. In my case, a `C:\Windows\System32\wintun.sys` had been left
behind for some reason, and was being loaded at startup, taking precedence
over the `wintun.dll` bundled with OpenConnect. Unfortunately, different
versions are not compatible, at least not entirely, while OpenConnect is
being tested with the bundled `wintun.dll` only.

To avoid this DLL hell, we shall load exclusively the bundled version of
`wintun.dll` from the application directory, and disregard any `wintun.dll`
or `wintun.sys` installed in system directories by other software.

Signed-off-by: Dimitri Papadopoulos <3350651-DimitriPapadopoulos@users.noreply.gitlab.com>
---
 wintun.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/wintun.c b/wintun.c
index 84111e76..7667cab9 100644
--- a/wintun.c
+++ b/wintun.c
@@ -69,8 +69,7 @@ static int init_wintun(struct openconnect_info *vpninfo)
 {
 	if (!vpninfo->wintun) {
 		vpninfo->wintun = LoadLibraryExW(L"wintun.dll", NULL,
-						 LOAD_LIBRARY_SEARCH_APPLICATION_DIR |
-						 LOAD_LIBRARY_SEARCH_SYSTEM32);
+						 LOAD_LIBRARY_SEARCH_APPLICATION_DIR);
 		if (!vpninfo->wintun) {
 			vpn_progress(vpninfo, PRG_DEBUG, _("Could not load wintun.dll\n"));
 			return -ENOENT;
-- 
2.50.1