gnetworkmonitornetlink: handle default route via device

If the default route is via a device rather than a particular IP
address, then neither RTA_DST nor RTA_GATEWAY will be present in the
RTM_NEWROUTE message, and so GNetworkMonitorNetlink would ignore it,
and then think there was no default route. (This could happen with
certain kinds of VPNs, if they were set to route all traffic through
the VPN.)

Fix this by recognizing routes that specify RTA_OIF ("output
interface") instead of RTA_GATEWAY.

https://bugzilla.gnome.org/show_bug.cgi?id=701609

diff --git a/gio/gnetworkmonitornetlink.c b/gio/gnetworkmonitornetlink.c
index 8983691..4f7d089 100644 (file)
--- a/gio/gnetworkmonitornetlink.c
+++ b/gio/gnetworkmonitornetlink.c
@@ -218,8 +218,7 @@ static void
 add_network (GNetworkMonitorNetlink *nl,
              GSocketFamily           family,
              gint                    dest_len,
-             guint8                 *dest,
-             guint8                 *gateway)
+             guint8                 *dest)
 {
   GInetAddress *dest_addr;
   GInetAddressMask *network;
@@ -245,8 +244,7 @@ static void
 remove_network (GNetworkMonitorNetlink *nl,
                 GSocketFamily           family,
                 gint                    dest_len,
-                guint8                 *dest,
-                guint8                 *gateway)
+                guint8                 *dest)
 {
   GInetAddress *dest_addr;
   GInetAddressMask *network;
@@ -305,7 +303,7 @@ read_netlink_messages (GSocket      *socket,
   struct rtmsg *rtmsg;
   struct rtattr *attr;
   gsize attrlen;
-  guint8 *dest, *gateway;
+  guint8 *dest, *gateway, *oif;
   gboolean retval = TRUE;
 
   iv.buffer = NULL;
@@ -367,22 +365,24 @@ read_netlink_messages (GSocket      *socket,
 
           attrlen = NLMSG_PAYLOAD (msg, sizeof (struct rtmsg));
           attr = RTM_RTA (rtmsg);
-          dest = gateway = NULL;
+          dest = gateway = oif = NULL;
           while (RTA_OK (attr, attrlen))
             {
               if (attr->rta_type == RTA_DST)
                 dest = RTA_DATA (attr);
               else if (attr->rta_type == RTA_GATEWAY)
                 gateway = RTA_DATA (attr);
+              else if (attr->rta_type == RTA_OIF)
+                oif = RTA_DATA (attr);
               attr = RTA_NEXT (attr, attrlen);
             }
 
-          if (dest || gateway)
+          if (dest || gateway || oif)
             {
               if (msg->nlmsg_type == RTM_NEWROUTE)
-                add_network (nl, rtmsg->rtm_family, rtmsg->rtm_dst_len, dest, gateway);
+                add_network (nl, rtmsg->rtm_family, rtmsg->rtm_dst_len, dest);
               else
-                remove_network (nl, rtmsg->rtm_family, rtmsg->rtm_dst_len, dest, gateway);
+                remove_network (nl, rtmsg->rtm_family, rtmsg->rtm_dst_len, dest);
               queue_request_dump (nl);
             }
           break;