kernel-netlink: Ignore routes with next hop during local subnet enumeration

These are not locally attached and we do the same already in kernel-pfroute.

Fixes #2554.

diff --git a/src/libcharon/plugins/kernel_netlink/kernel_netlink_net.c b/src/libcharon/plugins/kernel_netlink/kernel_netlink_net.c
index 6c31a481512b46966fbd79b340866c18e48b1f58..ce3b9e01f2290d8230a72926593ed9cd9a5a4257 100644 (file)
--- a/src/libcharon/plugins/kernel_netlink/kernel_netlink_net.c
+++ b/src/libcharon/plugins/kernel_netlink/kernel_netlink_net.c
@@ -2256,49 +2256,31 @@ METHOD(enumerator_t, enumerate_subnets, bool,
                                break;
                        case RTM_NEWROUTE:
                        {
-                               struct rtmsg *msg;
-                               struct rtattr *rta;
-                               size_t rtasize;
-                               chunk_t dst = chunk_empty;
-                               uint32_t oif = 0;
-
-                               msg = NLMSG_DATA(this->current);
+                               rt_entry_t route;
 
                                if (!route_usable(this->current))
                                {
                                        break;
                                }
-                               else if (msg->rtm_table && (
-                                                       msg->rtm_table == RT_TABLE_LOCAL ||
-                                                       msg->rtm_table == this->private->routing_table))
+                               parse_route(this->current, &route);
+
+                               if (route.table && (
+                                                       route.table == RT_TABLE_LOCAL ||
+                                                       route.table == this->private->routing_table))
                                {       /* ignore our own and the local routing tables */
                                        break;
                                }
-
-                               rta = RTM_RTA(msg);
-                               rtasize = RTM_PAYLOAD(this->current);
-                               while (RTA_OK(rta, rtasize))
-                               {
-                                       switch (rta->rta_type)
-                                       {
-                                               case RTA_DST:
-                                                       dst = chunk_create(RTA_DATA(rta), RTA_PAYLOAD(rta));
-                                                       break;
-                                               case RTA_OIF:
-                                                       if (RTA_PAYLOAD(rta) == sizeof(oif))
-                                                       {
-                                                               oif = *(uint32_t*)RTA_DATA(rta);
-                                                       }
-                                                       break;
-                                       }
-                                       rta = RTA_NEXT(rta, rtasize);
+                               else if (route.gtw.ptr)
+                               {       /* ignore routes via gateway/next hop */
+                                       break;
                                }
 
-                               if (dst.ptr && oif && if_indextoname(oif, this->ifname))
+                               if (route.dst.ptr && route.oif &&
+                                       if_indextoname(route.oif, this->ifname))
                                {
-                                       this->net = host_create_from_chunk(msg->rtm_family, dst, 0);
+                                       this->net = host_create_from_chunk(AF_UNSPEC, route.dst, 0);
                                        *net = this->net;
-                                       *mask = msg->rtm_dst_len;
+                                       *mask = route.dst_len;
                                        *ifname = this->ifname;
                                        return TRUE;
                                }