Windows: do_ifconfig() after open_tun()

When you had multiple TAP adapters and IPv6 configured you got an error
message about "you must also specify --dev-node" and openvpn exited.
Very inconvenient especially since this is only due to the fact that
Windows tries to set the adapter address before it is opened; for no
good reason.

This patch changes the order to IFCONFIG_AFTER_TUN_OPEN, moves some
initialization code to init_tun, where it belongs, and removes duplicate
code that is now no longer needed.

v2: do not use "%lu" in argv_printf(), crashes non-iservice usage

Signed-off-by: Heiko Hund <heiko.hund@sophos.com>
Signed-off-by: Gert Doering <gert@greenie.muc.de>
Acked-by: Gert Doering <gert@greenie.muc.de>
Acked-by: Heiko Hund <heiko.hund@sophos.com>
Message-Id: <20161009152550.GQ78279@greenie.muc.de>
URL: https://www.mail-archive.com/openvpn-devel@lists.sourceforge.net/msg12631.html
Signed-off-by: Gert Doering <gert@greenie.muc.de>

diff --git a/src/openvpn/tun.c b/src/openvpn/tun.c
index 103112f86e4213fd2cb26279dee1459f7ccc672e..af685de37ebf61c0fae2ed3a52e34a320d3f16f0 100644 (file)
--- a/src/openvpn/tun.c
+++ b/src/openvpn/tun.c
@@ -611,6 +611,21 @@ init_tun (const char *dev,       /* --dev option */
          tt->broadcast = generate_ifconfig_broadcast_addr (tt->local, tt->remote_netmask);
        }
 
+#ifdef WIN32
+      /*
+       * Make sure that both ifconfig addresses are part of the
+       * same .252 subnet.
+       */
+      if (tun)
+        {
+          verify_255_255_255_252 (tt->local, tt->remote_netmask);
+          tt->adapter_netmask = ~3;
+        }
+      else
+        {
+          tt->adapter_netmask = tt->remote_netmask;
+        }
+#endif
 
       tt->did_ifconfig_setup = true;
     }
@@ -1315,19 +1330,7 @@ do_ifconfig (struct tuntap *tt,
       }
 #elif defined (WIN32)
       {
-       /*
-        * Make sure that both ifconfig addresses are part of the
-        * same .252 subnet.
-        */
-       if (tun)
-         {
-           verify_255_255_255_252 (tt->local, tt->remote_netmask);
-           tt->adapter_netmask = ~3;
-         }
-       else
-         {
-           tt->adapter_netmask = tt->remote_netmask;
-         }
+        ASSERT (actual != NULL);
 
        switch (tt->options.ip_win32_type)
          {
@@ -1338,9 +1341,6 @@ do_ifconfig (struct tuntap *tt,
                 print_in_addr_t (tt->adapter_netmask, 0, &gc));
            break;
          case IPW32_SET_NETSH:
-           if (!strcmp (actual, "NULL"))
-             msg (M_FATAL, "Error: When using --ip-win32 netsh, if you have more than one TAP-Windows adapter, you must also specify --dev-node");
-
            netsh_ifconfig (&tt->options,
                            actual,
                            tt->local,
@@ -1354,25 +1354,6 @@ do_ifconfig (struct tuntap *tt,
 
     if ( do_ipv6 )
       {
-       char * saved_actual;
-       char iface[64];
-       DWORD idx;
-
-       if (!strcmp (actual, "NULL"))
-         msg (M_FATAL, "Error: When using --tun-ipv6, if you have more than one TAP-Windows adapter, you must also specify --dev-node");
-
-       idx = get_adapter_index_flexible(actual);
-       openvpn_snprintf(iface, sizeof(iface), "interface=%lu", idx);
-
-       /* on windows, OpenVPN does ifconfig first, open_tun later, so
-        * tt->actual_name might not yet be initialized, but routing code
-        * needs to know interface name - point to "actual", restore later
-        */
-       saved_actual = tt->actual_name;
-       tt->actual_name = (char*) actual;
-       /* we use adapter_index in add_route_ipv6 */
-       tt->adapter_index = idx;
-
        if (tt->options.msg_channel)
          {
            do_address_service (true, AF_INET6, tt);
@@ -1380,6 +1361,8 @@ do_ifconfig (struct tuntap *tt,
        else
          {
            /* example: netsh interface ipv6 set address interface=42 2001:608:8003::d store=active */
+           char iface[64];
+           openvpn_snprintf(iface, sizeof(iface), "interface=%lu", tt->adapter_index );
            argv_printf (&argv,
                         "%s%sc interface ipv6 set address %s %s store=active",
                         get_win_sys_path(),
@@ -1391,7 +1374,6 @@ do_ifconfig (struct tuntap *tt,
 
        /* explicit route needed */
        add_route_connected_v6_net(tt, es);
-       tt->actual_name = saved_actual;
       }
 #else
       msg (M_FATAL, "Sorry, but I don't know how to do 'ifconfig' commands on this operating system.  You should ifconfig your TUN/TAP device manually or use an --up script.");

diff --git a/src/openvpn/tun.h b/src/openvpn/tun.h
index 88431fbe0a4cf8ce4a9cc05d07759e31a9e8e8e8..6e3086c722861321e46b49624405e1d9f7762941 100644 (file)
--- a/src/openvpn/tun.h
+++ b/src/openvpn/tun.h
@@ -299,7 +299,7 @@ ifconfig_order(void)
 #elif defined(TARGET_NETBSD)
   return IFCONFIG_AFTER_TUN_OPEN;
 #elif defined(WIN32)
-  return IFCONFIG_BEFORE_TUN_OPEN;
+  return IFCONFIG_AFTER_TUN_OPEN;
 #elif defined(TARGET_ANDROID)
   return IFCONFIG_BEFORE_TUN_OPEN;
 #else