Do not restart dns client service as a part of --register-dns processing

As reported and discussed on Trac #775, restarting dns service has
unwanted side effects when there are dependent services. And it
appears unnecessary to restart this service to get DNS registered
on Windows.

Resolve by removing two actions from --register-dns:
'net stop dnscache' and 'net start dnscache' run through the service
or directly.

Trac: #775

Signed-off-by: Selva Nair <selva.nair@gmail.com>
Acked-by: Gert Doering <gert@greenie.muc.de>
Message-Id: <1480542696-7123-1-git-send-email-selva.nair@gmail.com>
URL: https://www.mail-archive.com/openvpn-devel@lists.sourceforge.net/msg13331.html
Signed-off-by: Gert Doering <gert@greenie.muc.de>

3 files changed, 5 insertions, 25 deletions

diff --git a/src/openvpn/options.c b/src/openvpn/options.c
index 038fcd3..47acd97 100644
--- a/src/openvpn/options.c
+++ b/src/openvpn/options.c
@@ -717,8 +717,8 @@ static const char usage_message[] =
   "--dhcp-pre-release : Ask Windows to release the previous TAP adapter lease on\n"
 "                       startup.\n"
   "--dhcp-release     : Ask Windows to release the TAP adapter lease on shutdown.\n"
-  "--register-dns  : Run net stop dnscache, net start dnscache, ipconfig /flushdns\n"
-  "                  and ipconfig /registerdns on connection initiation.\n"
+  "--register-dns  : Run ipconfig /flushdns and ipconfig /registerdns\n"
+  "                  on connection initiation.\n"
   "--tap-sleep n   : Sleep for n seconds after TAP adapter open before\n"
   "                  attempting to set adapter properties.\n"
   "--pause-exit         : When run from a console window, pause before exiting.\n"
diff --git a/src/openvpn/tun.c b/src/openvpn/tun.c
index 560b1a8..572e168 100644
--- a/src/openvpn/tun.c
+++ b/src/openvpn/tun.c
@@ -4597,23 +4597,9 @@ ipconfig_register_dns (const struct env_set *es)
   bool status;
   const char err[] = "ERROR: Windows ipconfig command failed";
 
-  msg (D_TUNTAP_INFO, "Start net commands...");
+  msg (D_TUNTAP_INFO, "Start ipconfig commands for register-dns...");
   netcmd_semaphore_lock ();
 
-  argv_printf (&argv, "%s%sc stop dnscache",
-	       get_win_sys_path(),
-	       WIN_NET_PATH_SUFFIX);
-  argv_msg (D_TUNTAP_INFO, &argv);
-  status = openvpn_execve_check (&argv, es, 0, err);
-  argv_reset(&argv);
-
-  argv_printf (&argv, "%s%sc start dnscache",
-	       get_win_sys_path(),
-	       WIN_NET_PATH_SUFFIX);
-  argv_msg (D_TUNTAP_INFO, &argv);
-  status = openvpn_execve_check (&argv, es, 0, err);
-  argv_reset(&argv);
-
   argv_printf (&argv, "%s%sc /flushdns",
 	       get_win_sys_path(),
 	       WIN_IPCONFIG_PATH_SUFFIX);
@@ -4629,7 +4615,7 @@ ipconfig_register_dns (const struct env_set *es)
   argv_reset(&argv);
 
   netcmd_semaphore_release ();
-  msg (D_TUNTAP_INFO, "End net commands...");
+  msg (D_TUNTAP_INFO, "End ipconfig commands for register-dns...");
 }
 
 void
diff --git a/src/openvpnserv/interactive.c b/src/openvpnserv/interactive.c
index 608bb0c..ec54216 100644
--- a/src/openvpnserv/interactive.c
+++ b/src/openvpnserv/interactive.c
@@ -899,8 +899,7 @@ RegisterDNS (LPVOID unused)
   WCHAR sys_path[MAX_PATH];
   DWORD timeout = RDNS_TIMEOUT * 1000; /* in milliseconds */
 
-  /* default paths of net and ipconfig commands */
-  WCHAR net[MAX_PATH]   = L"C:\\Windows\\system32\\net.exe";
+  /* default path of ipconfig command */
   WCHAR ipcfg[MAX_PATH] = L"C:\\Windows\\system32\\ipconfig.exe";
 
   struct
@@ -909,8 +908,6 @@ RegisterDNS (LPVOID unused)
       WCHAR *cmdline;
       DWORD timeout;
     } cmds [] = {
-                  { net,   L"net stop dnscache",     timeout },
-                  { net,   L"net start dnscache",    timeout },
                   { ipcfg, L"ipconfig /flushdns",    timeout },
                   { ipcfg, L"ipconfig /registerdns", timeout },
                 };
@@ -920,9 +917,6 @@ RegisterDNS (LPVOID unused)
 
   if(GetSystemDirectory(sys_path, MAX_PATH))
     {
-      _snwprintf (net, MAX_PATH, L"%s\\%s", sys_path, L"net.exe");
-      net[MAX_PATH-1] = L'\0';
-
       _snwprintf (ipcfg, MAX_PATH, L"%s\\%s", sys_path, L"ipconfig.exe");
       ipcfg[MAX_PATH-1] = L'\0';
     }