zebra: check router_flag change for neigh update

Neigh update can have router_flag change, from unset to set and
viceversa. This is the case where MAC, IP and VLAN are same but
entry's flag moved from R to not R bit and reverse case.

Router flag change needs to trigger bgpd to inform all evpn peers
to remove from the evpn route.

Testing Done:
Send GARP with and without R bit from host and validate neigh entry
and evpn neigh and  mac-ip route entry in zebra and bgpd.

Check Peer VTEP evpn route entry where router flag is (un)set.
With R-bit

Route [2]:[0]:[0]:[48]:[00:1f:2f:db:45:a6]:[128]:[2006:33:33:2::10]
VNI 1001
Imported from
27.0.0.16:5:[2]:[0]:[0]:[48]:[00:1f:2f:db:45:a6]:[128]:[2006:33:33:2::10]
   4435 5551
27.0.0.16 from MSP1(uplink-1) (27.0.0.9)
   Origin IGP, valid, external, bestpath-from-AS 4435, best
   Extended Community: RT:5551:1001 ET:8 ND:Router
   Flag
   AddPath ID: RX 0, TX 1261
   Last update: Wed Aug 15 20:52:14 2018

Without R-bit

Route [2]:[0]:[0]:[48]:[00:1f:2f:db:45:a6]:[128]:[2006:33:33:2::10]
VNI 1001
Imported from
27.0.0.16:5:[2]:[0]:[0]:[48]:[00:1f:2f:db:45:a6]:[128]:[2006:33:33:2::10]
   4435 5551
27.0.0.16 from MSP2(uplink-2) (27.0.0.10)
   Origin IGP, valid, external, bestpath-from-AS 4435, best
   Extended Community: RT:5551:1001 ET:8
   AddPath ID: RX 0, TX 1263
   Last update: Wed Aug 15 20:53:10 2018

Signed-off-by: Chirag Shah <chirag@cumulusnetworks.com>

diff --git a/zebra/zebra_vxlan.c b/zebra/zebra_vxlan.c
index a4f5f7b954af24927b068787334f5a9fd072d47e..0b034fd3b5e85d68f72cca133d49fd6668d93b3a 100644 (file)
--- a/zebra/zebra_vxlan.c
+++ b/zebra/zebra_vxlan.c
@@ -1961,6 +1961,7 @@ static int zvni_local_neigh_update(zebra_vni_t *zvni,
        char buf2[INET6_ADDRSTRLEN];
        zebra_neigh_t *n = NULL;
        zebra_mac_t *zmac = NULL, *old_zmac = NULL;
+       bool check_rbit = false;
 
        /* create a dummy MAC if the MAC is not already present */
        zmac = zvni_mac_lookup(zvni, macaddr);
@@ -1990,34 +1991,40 @@ static int zvni_local_neigh_update(zebra_vni_t *zvni,
        n = zvni_neigh_lookup(zvni, ip);
        if (n) {
                if (CHECK_FLAG(n->flags, ZEBRA_NEIGH_LOCAL)) {
+
+                       if (router_flag !=
+                           (CHECK_FLAG(n->flags, ZEBRA_NEIGH_ROUTER_FLAG)
+                                       ? 1 : 0))
+                               check_rbit = true;
+
                        if (memcmp(n->emac.octet, macaddr->octet,
                                   ETH_ALEN) == 0) {
                                /* Update any params and return - client doesn't
                                 * care about a purely local change.
                                 */
                                n->ifindex = ifp->ifindex;
-                               return 0;
-                       }
+                       } else {
 
-                       /* If the MAC has changed,
-                        * need to issue a delete first
-                        * as this means a different MACIP route.
-                        * Also, need to do some unlinking/relinking.
-                        */
-                       zvni_neigh_send_del_to_client(zvni->vni, &n->ip,
+                               /* If the MAC has changed,
+                                * need to issue a delete first
+                                * as this means a different MACIP route.
+                                * Also, need to do some unlinking/relinking.
+                                */
+                               zvni_neigh_send_del_to_client(zvni->vni, &n->ip,
                                                      &n->emac, 0);
-                       old_zmac = zvni_mac_lookup(zvni, &n->emac);
-                       if (old_zmac) {
-                               listnode_delete(old_zmac->neigh_list, n);
-                               zvni_deref_ip2mac(zvni, old_zmac, 0);
-                       }
+                               old_zmac = zvni_mac_lookup(zvni, &n->emac);
+                               if (old_zmac) {
+                                       listnode_delete(old_zmac->neigh_list, n);
+                                       zvni_deref_ip2mac(zvni, old_zmac, 0);
+                               }
 
-                       /* Update the forwarding info. */
-                       n->ifindex = ifp->ifindex;
-                       memcpy(&n->emac, macaddr, ETH_ALEN);
+                               /* Update the forwarding info. */
+                               n->ifindex = ifp->ifindex;
+                               memcpy(&n->emac, macaddr, ETH_ALEN);
 
-                       /* Link to new MAC */
-                       listnode_add_sort(zmac->neigh_list, n);
+                               /* Link to new MAC */
+                               listnode_add_sort(zmac->neigh_list, n);
+                       }
 
                } else
                /* Neighbor has moved from remote to local. */
@@ -2042,6 +2049,7 @@ static int zvni_local_neigh_update(zebra_vni_t *zvni,
                        n->r_vtep_ip.s_addr = 0;
                        SET_FLAG(n->flags, ZEBRA_NEIGH_LOCAL);
                        n->ifindex = ifp->ifindex;
+                       check_rbit = true;
                }
        } else {
                /* New neighbor - create */
@@ -2058,6 +2066,7 @@ static int zvni_local_neigh_update(zebra_vni_t *zvni,
                /* Set "local" forwarding info. */
                SET_FLAG(n->flags, ZEBRA_NEIGH_LOCAL);
                n->ifindex = ifp->ifindex;
+               check_rbit = true;
        }
 
        /*Mark Router flag (R-bit) */
@@ -2072,11 +2081,21 @@ static int zvni_local_neigh_update(zebra_vni_t *zvni,
        if (!CHECK_FLAG(zmac->flags, ZEBRA_MAC_LOCAL)) {
                if (IS_ZEBRA_DEBUG_VXLAN)
                        zlog_debug(
-                               "Skipping neigh %s add to client as MAC %s is not local on VNI %u",
+                               "Skipping neigh %s add to client as MAC %s is not local on VNI %u with flags 0x%x",
                                ipaddr2str(ip, buf2, sizeof(buf2)),
                                prefix_mac2str(macaddr, buf, sizeof(buf)),
-                               zvni->vni);
+                               zvni->vni, n->flags);
+
+               return 0;
+       }
 
+       if (!check_rbit) {
+               if (IS_ZEBRA_DEBUG_VXLAN)
+                       zlog_debug(
+                               "Skipping neigh %s with MAC %s on VNI %u add to client as router flag is not set.",
+                               ipaddr2str(ip, buf2, sizeof(buf2)),
+                               prefix_mac2str(macaddr, buf, sizeof(buf)),
+                               zvni->vni);
                return 0;
        }