Skip DNS address validation

When adding IPv4 DNS servers without interactive service use
"validate=no", on Windows 7 and higher, to skip time consuming automatic
address validation, that is on by default.

Fix uses adapted code from commit 786e06a

Signed-off-by: Domagoj Pensa <domagoj@pensa.hr>
Acked-by: Lev Stipakov <lstipakov@gmail.com>
Acked-by: Selva Nair <selva.nair@gmail.com>
Message-Id: <20200205124615.15758-2-domagoj@pensa.hr>
URL: https://www.mail-archive.com/openvpn-devel@lists.sourceforge.net/msg19355.html
Signed-off-by: Gert Doering <gert@greenie.muc.de>

diff --git a/src/openvpn/tun.c b/src/openvpn/tun.c
index 1f848d24419d9c0a2e7d60293451f5b2e34e6344..a81842fb72b22790a100add95cb37feef1d446e3 100644 (file)
--- a/src/openvpn/tun.c
+++ b/src/openvpn/tun.c
@@ -5224,6 +5224,7 @@ netsh_ifconfig_options(const char *type,
     struct gc_arena gc = gc_new();
     struct argv argv = argv_new();
     bool delete_first = false;
+    bool is_dns = !strcmp(type, "dns");
 
     /* first check if we should delete existing DNS/WINS settings from TAP interface */
     if (test_first)
@@ -5267,6 +5268,14 @@ netsh_ifconfig_options(const char *type,
                             type,
                             flex_name,
                             print_in_addr_t(addr_list[i], 0, &gc));
+
+                /* disable slow address validation on Windows 7 and higher */
+                /* only for DNS */
+                if (is_dns && win32_version_info() >= WIN_7)
+                {
+                    argv_printf_cat(&argv, "%s", "validate=no");
+                }
+
                 netsh_command(&argv, 2, M_FATAL);
 
                 ++count;