bgpd: atomic-aggregate is lost when we aggregate another aggregate that has atomic-aggregate

This patch ensures that we don't accidently loose the atomic-aggregate
when we aggregate another aggregate that also has atomic-aggregates.

Signed-off-by: Daniel Walton <dwalton@cumulusnetworks.com>
diff --git a/bgpd/bgp_attr.c b/bgpd/bgp_attr.c
index ac67c62..3b96bb2 100644
--- a/bgpd/bgp_attr.c
+++ b/bgpd/bgp_attr.c
@@ -724,7 +724,8 @@
 struct attr *
 bgp_attr_aggregate_intern (struct bgp *bgp, u_char origin,
 			   struct aspath *aspath,
-			   struct community *community, int as_set)
+			   struct community *community, int as_set,
+			   u_char atomic_aggregate)
 {
   struct attr attr;
   struct attr *new;
@@ -757,7 +758,7 @@
   attre.weight = BGP_ATTR_DEFAULT_WEIGHT;
   attre.mp_nexthop_len = IPV6_MAX_BYTELEN;
 
-  if (! as_set)
+  if (! as_set || atomic_aggregate)
     attr.flag |= ATTR_FLAG_BIT (BGP_ATTR_ATOMIC_AGGREGATE);
   attr.flag |= ATTR_FLAG_BIT (BGP_ATTR_AGGREGATOR);
   if (CHECK_FLAG (bgp->config, BGP_CONFIG_CONFEDERATION))
diff --git a/bgpd/bgp_attr.h b/bgpd/bgp_attr.h
index 0cd0b77..8457f40 100644
--- a/bgpd/bgp_attr.h
+++ b/bgpd/bgp_attr.h
@@ -168,7 +168,7 @@
 extern struct attr *bgp_attr_default_intern (u_char);
 extern struct attr *bgp_attr_aggregate_intern (struct bgp *, u_char,
                                         struct aspath *, 
-                                        struct community *, int as_set);
+                                        struct community *, int as_set, u_char);
 extern bgp_size_t bgp_packet_attribute (struct bgp *bgp, struct peer *,
 					struct stream *, struct attr *,
 					struct prefix *, afi_t, safi_t,
diff --git a/bgpd/bgp_route.c b/bgpd/bgp_route.c
index 78cd53b..7f98f94 100644
--- a/bgpd/bgp_route.c
+++ b/bgpd/bgp_route.c
@@ -4753,6 +4753,7 @@
   struct bgp_info *new;
   int first = 1;
   unsigned long match = 0;
+  u_char atomic_aggregate = 0;
 
   /* ORIGIN attribute: If at least one route among routes that are
      aggregated has ORIGIN with the value INCOMPLETE, then the
@@ -4797,6 +4798,9 @@
 	      }
 #endif /* AGGREGATE_NEXTHOP_CHECK */
 
+            if (ri->attr->flag & ATTR_FLAG_BIT(BGP_ATTR_ATOMIC_AGGREGATE))
+              atomic_aggregate = 1;
+
 	    if (ri->sub_type != BGP_ROUTE_AGGREGATE)
 	      {
 		if (aggregate->summary_only)
@@ -4883,7 +4887,8 @@
       rn = bgp_node_get (table, p);
       new = info_make(ZEBRA_ROUTE_BGP, BGP_ROUTE_AGGREGATE, bgp->peer_self,
 		      bgp_attr_aggregate_intern(bgp, origin, aspath, community,
-						aggregate->as_set), rn);
+						aggregate->as_set,
+                                                atomic_aggregate), rn);
       SET_FLAG (new->flags, BGP_INFO_VALID);
 
       bgp_info_add (rn, new);
@@ -4989,6 +4994,7 @@
   struct aspath *asmerge = NULL;
   struct community *community = NULL;
   struct community *commerge = NULL;
+  u_char atomic_aggregate = 0;
 
   table = bgp->rib[afi][safi];
 
@@ -5010,6 +5016,9 @@
 	    if (BGP_INFO_HOLDDOWN (ri))
 	      continue;
 
+            if (ri->attr->flag & ATTR_FLAG_BIT(BGP_ATTR_ATOMIC_AGGREGATE))
+              atomic_aggregate = 1;
+
 	    if (ri->sub_type != BGP_ROUTE_AGGREGATE)
 	      {
 		/* summary-only aggregate route suppress aggregated
@@ -5073,7 +5082,8 @@
       rn = bgp_node_get (table, p);
       new = info_make(ZEBRA_ROUTE_BGP, BGP_ROUTE_AGGREGATE, bgp->peer_self,
 		      bgp_attr_aggregate_intern(bgp, origin, aspath, community,
-						aggregate->as_set), rn);
+						aggregate->as_set,
+                                                atomic_aggregate), rn);
       SET_FLAG (new->flags, BGP_INFO_VALID);
 
       bgp_info_add (rn, new);