ospf6d: Disable and delete OSPFv3 areas that no longer have interfaces or configuration. (backport #18393)

ospf6d/ospf6_area.c

@@ -360,12 +360,25 @@ void ospf6_area_delete(struct ospf6_area *oa)
 	ospf6_route_table_delete(oa->summary_router);
 
 	listnode_delete(oa->ospf6->area_list, oa);
+
+	if (oa->ospf6->backbone == oa)
+		oa->ospf6->backbone = NULL;
 	oa->ospf6 = NULL;
 
 	/* free area */
 	XFREE(MTYPE_OSPF6_AREA, oa);
 }
 
+void ospf6_area_no_config_delete(struct ospf6_area *oa)
+{
+	if ((oa->if_list->count == 0) && (oa->range_table->count == 0) &&
+	    (oa->nssa_range_table->count == 0) && !IS_AREA_STUB(oa) && !IS_AREA_NSSA(oa) &&
+	    !PREFIX_NAME_IN(oa) && !PREFIX_NAME_OUT(oa) && !IMPORT_NAME(oa) && !EXPORT_NAME(oa)) {
+		ospf6_area_disable(oa);
+		ospf6_area_delete(oa);
+	}
+}
+
 struct ospf6_area *ospf6_area_lookup_by_area_id(uint32_t area_id)
 {
 	struct ospf6_area *oa;
@@ -409,6 +422,7 @@ void ospf6_area_disable(struct ospf6_area *oa)
 	struct listnode *node, *nnode;
 	struct ospf6_interface *oi;
 
+	UNSET_FLAG(oa->flag, OSPF6_AREA_ACTIVE);
 	UNSET_FLAG(oa->flag, OSPF6_AREA_ENABLE);
 
 	for (ALL_LIST_ELEMENTS(oa->if_list, node, nnode, oi))
@@ -646,6 +660,9 @@ DEFUN (no_area_range,
 	}
 	ospf6_route_remove(range, oa->range_table);
 
+	/* Delete area if no interfaces or configuration. */
+	ospf6_area_no_config_delete(oa);
+
 	return CMD_SUCCESS;
 }
 
@@ -814,6 +831,9 @@ DEFUN (no_area_filter_list,
 	if (ospf6_check_and_set_router_abr(area->ospf6))
 		ospf6_schedule_abr_task(ospf6);
 
+	/* Delete area if no interfaces or configuration. */
+	ospf6_area_no_config_delete(area);
+
 	return CMD_SUCCESS;
 }
 
@@ -939,6 +959,9 @@ DEFUN (no_area_import_list,
 	if (ospf6_check_and_set_router_abr(area->ospf6))
 		ospf6_schedule_abr_task(ospf6);
 
+	/* Delete area if no interfaces or configuration. */
+	ospf6_area_no_config_delete(area);
+
 	return CMD_SUCCESS;
 }
 
@@ -1002,6 +1025,9 @@ DEFUN (no_area_export_list,
 	if (ospf6_check_and_set_router_abr(area->ospf6))
 		ospf6_schedule_abr_task(ospf6);
 
+	/* Delete area if no interfaces or configuration. */
+	ospf6_area_no_config_delete(area);
+
 	return CMD_SUCCESS;
 }
 
@@ -1338,6 +1364,9 @@ DEFUN (no_ospf6_area_stub_no_summary,
 	ospf6_area_stub_unset(ospf6, area);
 	ospf6_area_no_summary_unset(ospf6, area);
 
+	/* Delete area if no interfaces or configuration. */
+	ospf6_area_no_config_delete(area);
+
 	return CMD_SUCCESS;
 }
 
@@ -1418,6 +1447,9 @@ DEFPY(no_ospf6_area_nssa, no_ospf6_area_nssa_cmd,
 	ospf6_area_no_summary_unset(ospf6, area);
 	ospf6_nssa_default_originate_unset(ospf6, area);
 
+	/* Delete area if no interfaces or configuration. */
+	ospf6_area_no_config_delete(area);
+
 	return CMD_SUCCESS;
 }
 

ospf6d/ospf6_area.h

@@ -144,6 +144,7 @@ extern int ospf6_area_cmp(void *va, void *vb);
 extern struct ospf6_area *ospf6_area_create(uint32_t area_id,
 					    struct ospf6 *ospf6, int df);
 extern void ospf6_area_delete(struct ospf6_area *oa);
+extern void ospf6_area_no_config_delete(struct ospf6_area *oa);
 extern struct ospf6_area *ospf6_area_lookup(uint32_t area_id,
 					    struct ospf6 *ospf6);
 extern struct ospf6_area *ospf6_area_lookup_by_area_id(uint32_t area_id);

ospf6d/ospf6_interface.c

@@ -1822,6 +1822,9 @@ void ospf6_interface_stop(struct ospf6_interface *oi)
 	if (oa->if_list->count == 0) {
 		UNSET_FLAG(oa->flag, OSPF6_AREA_ENABLE);
 		ospf6_abr_disable_area(oa);
+
+		/* Delete area if no interfaces or configuration. */
+		ospf6_area_no_config_delete(oa);
 	}
 }