zebra: netlink: get blackhole routes from kernel

support processing of RTN_BLACKHOLE et al. from kernel and dump them
into appropriate blackhole rib entries.

Signed-off-by: David Lamparter <equinox@opensourcerouting.org>

diff --git a/zebra/rt_netlink.c b/zebra/rt_netlink.c
index fa38c21abfa928b8c9dbd60b228bd490d1022963..0076e915690b77578e5f5d87ab28cb86cfc8fcf1 100644 (file)
--- a/zebra/rt_netlink.c
+++ b/zebra/rt_netlink.c
@@ -240,13 +240,27 @@ static int netlink_route_change_read_unicast(struct sockaddr_nl *snl,
        void *gate = NULL;
        void *prefsrc = NULL; /* IPv4 preferred source host address */
        void *src = NULL;     /* IPv6 srcdest   source prefix */
+       enum blackhole_type bh_type = BLACKHOLE_UNSPEC;
 
        rtm = NLMSG_DATA(h);
 
        if (startup && h->nlmsg_type != RTM_NEWROUTE)
                return 0;
-       if (startup && rtm->rtm_type != RTN_UNICAST)
+       switch (rtm->rtm_type) {
+       case RTN_UNICAST:
+               break;
+       case RTN_BLACKHOLE:
+               bh_type = BLACKHOLE_NULL;
+               break;
+       case RTN_UNREACHABLE:
+               bh_type = BLACKHOLE_REJECT;
+               break;
+       case RTN_PROHIBIT:
+               bh_type = BLACKHOLE_ADMINPROHIB;
+               break;
+       default:
                return 0;
+       }
 
        len = h->nlmsg_len - NLMSG_LENGTH(sizeof(struct rtmsg));
        if (len < 0)
@@ -380,8 +394,10 @@ static int netlink_route_change_read_unicast(struct sockaddr_nl *snl,
                                nh.type = (afi == AFI_IP)
                                        ? NEXTHOP_TYPE_IPV4
                                        : NEXTHOP_TYPE_IPV6;
-                       else
+                       else {
                                nh.type = NEXTHOP_TYPE_BLACKHOLE;
+                               nh.bh_type = bh_type;
+                       }
                        nh.ifindex = index;
                        if (prefsrc)
                                memcpy(&nh.src, prefsrc, sz);
@@ -623,18 +639,10 @@ int netlink_route_change(struct sockaddr_nl *snl, struct nlmsghdr *h,
        if (len < 0)
                return -1;
 
-       switch (rtm->rtm_type) {
-       case RTN_UNICAST:
-               netlink_route_change_read_unicast(snl, h, ns_id, startup);
-               break;
-       case RTN_MULTICAST:
+       if (rtm->rtm_type == RTN_MULTICAST)
                netlink_route_change_read_multicast(snl, h, ns_id, startup);
-               break;
-       default:
-               return 0;
-               break;
-       }
-
+       else
+               netlink_route_change_read_unicast(snl, h, ns_id, startup);
        return 0;
 }