ospf6d: ospf6 route installation when changed from nssa to regular area.

Problem:
Delay in ospfv3 route installation when area gets converted to regular
from NSSA.

RCA:
when area gets converted from NSSA to normal the type-7(NSSA_LSAs)
gets flushed from the area, as a result the external routes
learnt from these type-7s gets removed. Once the area is moved
to nomral the type 5 lsas needs to flooded through the area
so that routes are re-learnt. however there is a delay in
flooding of these routes until these routes are refreshed.
Due to this there is delay installation of these routes.

Fix:
The Fix involves refreshing of the type 5 lsas once the area
is changed from nssa to regular area.

Signed-off-by: Manoj Naragund <mnaragund@vmware.com>

1 files changed, 48 insertions, 0 deletions

diff --git a/ospf6d/ospf6_nssa.c b/ospf6d/ospf6_nssa.c
index b1bff69f06..569e536e36 100644
--- a/ospf6d/ospf6_nssa.c
+++ b/ospf6d/ospf6_nssa.c
@@ -1092,7 +1092,25 @@ static void ospf6_check_and_originate_type7_lsa(struct ospf6_area *area)
 			ospf6_nssa_lsa_originate(aggr->route, area, true);
 		}
 	}
+}
+
+static void ospf6_ase_lsa_refresh(struct ospf6 *o)
+{
+	struct ospf6_lsa *old;
 
+	for (struct ospf6_route *route = ospf6_route_head(o->external_table);
+	     route; route = ospf6_route_next(route)) {
+		old = ospf6_lsdb_lookup(htons(OSPF6_LSTYPE_AS_EXTERNAL),
+					route->path.origin.id, o->router_id,
+					o->lsdb);
+		if (old) {
+			THREAD_OFF(old->refresh);
+			thread_add_event(master, ospf6_lsa_refresh, old, 0,
+					 &old->refresh);
+		} else {
+			ospf6_as_external_lsa_originate(route, o);
+		}
+	}
 }
 
 void ospf6_area_nssa_update(struct ospf6_area *area)
@@ -1136,6 +1154,36 @@ void ospf6_area_nssa_update(struct ospf6_area *area)
 		if (IS_OSPF6_DEBUG_NSSA)
 			zlog_debug("Normal area %s", area->name);
 		ospf6_nssa_flush_area(area);
+
+		/* Check if router is ABR */
+		if (ospf6_check_and_set_router_abr(area->ospf6)) {
+			if (IS_OSPF6_DEBUG_NSSA)
+				zlog_debug("Router is ABR area %s", area->name);
+			ospf6_schedule_abr_task(area->ospf6);
+			ospf6_ase_lsa_refresh(area->ospf6);
+		} else {
+			uint16_t type;
+			struct ospf6_lsa *lsa = NULL;
+
+			/*
+			 * Refresh all type-5 LSAs so they get installed
+			 * in the converted ares
+			 */
+			if (IS_OSPF6_DEBUG_NSSA)
+				zlog_debug("Refresh type-5 LSAs, area %s",
+					   area->name);
+
+			type = htons(OSPF6_LSTYPE_AS_EXTERNAL);
+			for (ALL_LSDB_TYPED_ADVRTR(area->ospf6->lsdb, type,
+						   area->ospf6->router_id,
+						   lsa)) {
+				if (IS_OSPF6_DEBUG_NSSA)
+					ospf6_lsa_header_print(lsa);
+				THREAD_OFF(lsa->refresh);
+				thread_add_event(master, ospf6_lsa_refresh, lsa,
+						 0, &lsa->refresh);
+			}
+		}
 	}
 }