ospfd: install Type-7 when NSSA enabled after redistribution

If NSSA is enabled before redistribution is configured, Type-7 LSA's
are installed. But if NSSA is enabled after redistribution is
configured, Type-7 LSAs are missing.

With this change, when NSSA is enabled, scan for external LSA's and
if they exist, install Type-7.

Signed-off-by: Alexander Chernavin <achernavin@netgate.com>

ospfd/ospf_abr.c

@@ -1802,6 +1802,7 @@ static int ospf_abr_task_timer(struct thread *thread)
 
 	ospf_abr_task(ospf);
 	ospf_abr_nssa_task(ospf); /* if nssa-abr, then scan Type-7 LSDB */
+	ospf_asbr_nssa_redist_task(ospf);
 
 	return 0;
 }

ospfd/ospf_asbr.c

@@ -275,6 +275,30 @@ void ospf_asbr_status_update(struct ospf *ospf, uint8_t status)
 	ospf_router_lsa_update(ospf);
 }
 
+/* If there's redistribution configured, we need to refresh external
+ * LSAs in order to install Type-7 and flood to all NSSA Areas
+ */
+void ospf_asbr_nssa_redist_task(struct ospf *ospf)
+{
+	int type;
+
+	for (type = 0; type < ZEBRA_ROUTE_MAX; type++) {
+		struct list *red_list;
+		struct listnode *node;
+		struct ospf_redist *red;
+
+		red_list = ospf->redist[type];
+		if (!red_list)
+			continue;
+
+		for (ALL_LIST_ELEMENTS_RO(red_list, node, red))
+			ospf_external_lsa_refresh_type(
+				ospf, type, red->instance, LSA_REFRESH_FORCE);
+	}
+
+	ospf_external_lsa_refresh_default(ospf);
+}
+
 void ospf_redistribute_withdraw(struct ospf *ospf, uint8_t type,
 				unsigned short instance)
 {

ospfd/ospf_asbr.h

@@ -72,6 +72,7 @@ extern struct external_info *ospf_external_info_lookup(struct ospf *, uint8_t,
 						       unsigned short,
 						       struct prefix_ipv4 *);
 extern void ospf_asbr_status_update(struct ospf *, uint8_t);
+extern void ospf_asbr_nssa_redist_task(struct ospf *ospf);
 
 extern void ospf_redistribute_withdraw(struct ospf *, uint8_t, unsigned short);
 extern void ospf_asbr_check(void);