Initial revision

1 files changed, 726 insertions, 0 deletions

diff --git a/ospfd/ospf_ia.c b/ospfd/ospf_ia.c
new file mode 100644
index 00000000..32c8d86b
--- /dev/null
+++ b/ospfd/ospf_ia.c
@@ -0,0 +1,726 @@
+/*
+ * OSPF inter-area routing.
+ * Copyright (C) 1999, 2000 Alex Zinin, Toshiaki Takada
+ *
+ * This file is part of GNU Zebra.
+ *
+ * GNU Zebra is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2, or (at your option) any
+ * later version.
+ *
+ * GNU Zebra is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with GNU Zebra; see the file COPYING.  If not, write to the Free
+ * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+ * 02111-1307, USA.
+ */
+
+
+#include <zebra.h>
+
+#include "thread.h"
+#include "memory.h"
+#include "hash.h"
+#include "linklist.h"
+#include "prefix.h"
+#include "table.h"
+#include "log.h"
+
+#include "ospfd/ospfd.h"
+#include "ospfd/ospf_interface.h"
+#include "ospfd/ospf_ism.h"
+#include "ospfd/ospf_asbr.h"
+#include "ospfd/ospf_lsa.h"
+#include "ospfd/ospf_lsdb.h"
+#include "ospfd/ospf_neighbor.h"
+#include "ospfd/ospf_nsm.h"
+#include "ospfd/ospf_spf.h"
+#include "ospfd/ospf_route.h"
+#include "ospfd/ospf_ase.h"
+#include "ospfd/ospf_abr.h"
+#include "ospfd/ospf_ia.h"
+#include "ospfd/ospf_dump.h"
+
+#define DEBUG
+
+struct ospf_route *
+ospf_find_abr_route (struct route_table *rtrs, 
+                     struct prefix_ipv4 *abr,
+                     struct ospf_area *area)
+{
+  struct route_node *rn;
+  struct ospf_route *or;
+  listnode node;
+
+  if ((rn = route_node_lookup (rtrs, (struct prefix *) abr)) == NULL)
+    return NULL;
+
+  route_unlock_node (rn);
+
+  for (node = listhead ((list) rn->info); node; nextnode (node))
+    if ((or = getdata (node)) != NULL)
+      if (IPV4_ADDR_SAME (&or->u.std.area_id, &area->area_id) && (or->u.std.flags & ROUTER_LSA_BORDER))
+	return or;
+
+  return NULL;
+}
+
+void
+ospf_ia_network_route (struct route_table *rt, struct prefix_ipv4 *p,
+                       struct ospf_route *new_or, struct ospf_route *abr_or)
+{
+  struct route_node *rn1;
+  struct ospf_route *or;
+
+  if (IS_DEBUG_OSPF_EVENT)
+    zlog_info ("ospf_ia_network_route(): processing summary route to %s/%d", 
+	       inet_ntoa (p->prefix), p->prefixlen);
+
+  /* Find a route to the same dest */
+  if ((rn1 = route_node_lookup (rt, (struct prefix *) p)))
+    {
+      int res;
+
+      route_unlock_node (rn1);
+
+      if ((or = rn1->info))
+	{
+	  if (IS_DEBUG_OSPF_EVENT)
+	    zlog_info ("ospf_ia_network_route(): "
+		       "Found a route to the same network");
+	  /* Check the existing route. */
+	  if ((res = ospf_route_cmp (new_or, or)) < 0)
+	    {
+	      /* New route is better, so replace old one. */
+	      ospf_route_subst (rn1, new_or, abr_or);
+	    }
+	  else if (res == 0)
+	    {
+	      /* New and old route are equal, so next hops can be added. */
+	      route_lock_node (rn1);
+	      ospf_route_copy_nexthops (or, abr_or->path);
+	      route_unlock_node (rn1);
+
+	      /* new route can be deleted, because existing route has been updated. */
+	      ospf_route_free (new_or);
+	    }
+	  else
+	    {
+	      /* New route is worse, so free it. */
+	      ospf_route_free (new_or);
+	      return;
+	    }
+	} /* if (or)*/
+    } /*if (rn1)*/
+  else
+    { /* no route */
+      if (IS_DEBUG_OSPF_EVENT)
+	zlog_info ("ospf_ia_network_route(): add new route to %s/%d",
+		   inet_ntoa (p->prefix), p->prefixlen);
+      ospf_route_add (rt, p, new_or, abr_or);
+    }
+}
+
+void
+ospf_ia_router_route (struct route_table *rt, struct prefix_ipv4 *p,
+                      struct ospf_route *new_or, struct ospf_route *abr_or)
+{
+  struct route_node *rn;
+  struct ospf_route *or = NULL;
+  int ret;
+
+  if (IS_DEBUG_OSPF_EVENT)
+    zlog_info ("ospf_ia_router_route(): considering %s/%d", 
+	       inet_ntoa (p->prefix), p->prefixlen);
+  /* Find a route to the same dest */
+  rn = route_node_get (rt,(struct prefix *) p);
+   
+  if (rn->info == NULL)
+    /* This is a new route */
+    rn->info = list_new ();
+  else
+    {
+      struct ospf_area *or_area;
+      or_area = ospf_area_lookup_by_area_id (new_or->u.std.area_id);
+      assert (or_area);
+      /* This is an additional route */
+      route_unlock_node (rn);
+      or = ospf_find_asbr_route_through_area (rt, p, or_area);
+    }
+
+  if (or)
+    {
+      if (IS_DEBUG_OSPF_EVENT)
+	zlog_info ("ospf_ia_router_route(): "
+		   "a route to the same ABR through the same area exists");
+      /* New route is better */
+      if ((ret = ospf_route_cmp (new_or, or)) < 0)
+	{
+	  listnode_delete (rn->info, or);
+	  ospf_route_free (or);
+	  /* proceed down */
+	}
+      /* Routes are the same */
+      else if (ret == 0)
+	{
+	  if (IS_DEBUG_OSPF_EVENT)
+	    zlog_info ("ospf_ia_router_route(): merging the new route");
+
+	  ospf_route_copy_nexthops (or, abr_or->path);
+	  ospf_route_free (new_or);
+	  return;
+	}
+      /* New route is worse */
+      else
+	{
+	  if (IS_DEBUG_OSPF_EVENT)
+	    zlog_info ("ospf_ia_router_route(): skipping the new route");
+	  ospf_route_free (new_or);
+	  return;
+	}
+    }
+
+  ospf_route_copy_nexthops (new_or, abr_or->path);
+
+  if (IS_DEBUG_OSPF_EVENT)
+    zlog_info ("ospf_ia_router_route(): adding the new route"); 
+
+  listnode_add (rn->info, new_or);
+}
+
+
+struct ia_args
+{
+  struct route_table *rt;
+  struct route_table *rtrs;
+  struct ospf_area *area;
+};
+
+int
+process_summary_lsa (struct ospf_lsa *l, void *v, int i)
+{
+  struct ospf_area_range *range;
+  struct ospf_route *abr_or, *new_or;
+  struct summary_lsa *sl;
+  struct prefix_ipv4 p, abr;
+  u_int32_t metric;
+  struct ia_args *args;
+
+  if (l == NULL)
+    return 0;
+
+  args = (struct ia_args *) v;
+  sl = (struct summary_lsa *) l->data;
+
+  if (IS_DEBUG_OSPF_EVENT)
+    zlog_info ("process_summary_lsa(): LS ID: %s", inet_ntoa (sl->header.id));
+
+  metric = GET_METRIC (sl->metric);
+   
+  if (metric == OSPF_LS_INFINITY)
+    return 0;
+
+  if (IS_LSA_MAXAGE (l))
+    return 0;
+
+  if (ospf_lsa_is_self_originated (l))
+    return 0;
+
+  p.family = AF_INET;
+  p.prefix = sl->header.id;
+   
+  if (sl->header.type == OSPF_SUMMARY_LSA)
+    p.prefixlen = ip_masklen (sl->mask);
+  else
+    p.prefixlen = IPV4_MAX_BITLEN;
+      
+  apply_mask_ipv4 (&p);
+
+  if (sl->header.type == OSPF_SUMMARY_LSA &&
+      (range = ospf_area_range_match_any (ospf_top, &p)) &&
+      ospf_area_range_active (range))
+    return 0;
+
+  if (ospf_top->abr_type != OSPF_ABR_STAND &&
+      args->area->external_routing != OSPF_AREA_DEFAULT &&
+      p.prefix.s_addr == OSPF_DEFAULT_DESTINATION &&
+      p.prefixlen == 0)
+    return 0; /* Ignore summary default from a stub area */
+
+  abr.family = AF_INET;
+  abr.prefix = sl->header.adv_router;
+  abr.prefixlen = IPV4_MAX_BITLEN;
+  apply_mask_ipv4 (&abr);
+
+  abr_or = ospf_find_abr_route (args->rtrs, &abr, args->area);
+
+  if (abr_or == NULL)
+    return 0;
+
+  new_or = ospf_route_new ();
+  new_or->type = OSPF_DESTINATION_NETWORK;
+  new_or->id = sl->header.id;
+  new_or->mask = sl->mask;
+  new_or->u.std.options = sl->header.options;
+  new_or->u.std.origin = (struct lsa_header *) sl;
+  new_or->cost = abr_or->cost + metric;
+  new_or->u.std.area_id = args->area->area_id;
+#ifdef HAVE_NSSA
+  new_or->u.std.external_routing = args->area->external_routing;
+#endif /* HAVE_NSSA */
+  new_or->path_type = OSPF_PATH_INTER_AREA;
+
+  if (sl->header.type == OSPF_SUMMARY_LSA)
+    ospf_ia_network_route (args->rt, &p, new_or, abr_or);
+  else 
+    {
+      new_or->type = OSPF_DESTINATION_ROUTER;
+      new_or->u.std.flags = ROUTER_LSA_EXTERNAL;
+      ospf_ia_router_route (args->rtrs, &p, new_or, abr_or);
+    }
+
+  return 0;
+}
+
+void
+ospf_examine_summaries (struct ospf_area * area,
+			struct route_table *lsdb_rt,
+                        struct route_table *rt,
+                        struct route_table *rtrs)
+{
+  struct ia_args args = {rt, rtrs, area};
+  foreach_lsa (lsdb_rt, &args, 0, process_summary_lsa);
+}
+
+int
+ospf_area_is_transit (struct ospf_area *area)
+{
+  return (area->transit == OSPF_TRANSIT_TRUE) ||
+    ospf_full_virtual_nbrs(area); /* Cisco forgets to set the V-bit :( */
+}
+
+void
+ospf_update_network_route (struct route_table *rt, 
+                           struct route_table *rtrs,
+                           struct summary_lsa *lsa,
+                           struct prefix_ipv4 *p,
+                           struct ospf_area *area)
+{
+  struct route_node *rn;
+  struct ospf_route *or, *abr_or, *new_or;
+  struct prefix_ipv4 abr;
+  u_int32_t cost;
+
+  abr.family = AF_INET;
+  abr.prefix =lsa->header.adv_router;
+  abr.prefixlen = IPV4_MAX_BITLEN;
+  apply_mask_ipv4 (&abr);
+
+  abr_or = ospf_find_abr_route (rtrs, &abr, area);
+
+  if (abr_or == NULL)
+    {
+      if (IS_DEBUG_OSPF_EVENT)
+	zlog_info ("ospf_update_network_route(): can't find a route to the ABR");
+      return;
+    }
+
+  cost = abr_or->cost + GET_METRIC (lsa->metric);
+
+  rn = route_node_lookup (rt, (struct prefix *) p);
+
+  if (! rn)
+    {
+      if (ospf_top->abr_type != OSPF_ABR_SHORTCUT)
+        return; /* Standard ABR can update only already installed
+                   backbone paths                                       */
+      if (IS_DEBUG_OSPF_EVENT)
+	zlog_info ("ospf_update_network_route(): "
+		   "Allowing Shortcut ABR to add new route");
+      new_or = ospf_route_new ();
+      new_or->type = OSPF_DESTINATION_NETWORK;
+      new_or->id = lsa->header.id;
+      new_or->mask = lsa->mask;
+      new_or->u.std.options = lsa->header.options;
+      new_or->u.std.origin = (struct lsa_header *) lsa;
+      new_or->cost = cost;
+      new_or->u.std.area_id = area->area_id;
+#ifdef HAVE_NSSA
+      new_or->u.std.external_routing = area->external_routing;
+#endif /* HAVE_NSSA */
+      new_or->path_type = OSPF_PATH_INTER_AREA;
+      ospf_route_add (rt, p, new_or, abr_or);
+
+      return;
+    }
+  else
+    {
+      route_unlock_node (rn);
+      if (rn->info == NULL)
+        return;
+    }
+
+  or = rn->info;
+
+  if (or->path_type != OSPF_PATH_INTRA_AREA &&
+      or->path_type != OSPF_PATH_INTER_AREA)
+    {
+      if (IS_DEBUG_OSPF_EVENT)
+	zlog_info ("ospf_update_network_route(): ERR: path type is wrong");
+      return;
+    }
+
+  if (ospf_top->abr_type == OSPF_ABR_SHORTCUT)
+    {
+      if (or->path_type == OSPF_PATH_INTRA_AREA &&
+	  !OSPF_IS_AREA_ID_BACKBONE (or->u.std.area_id))
+	{
+	  if (IS_DEBUG_OSPF_EVENT)
+	    zlog_info ("ospf_update_network_route(): Shortcut: "
+		       "this intra-area path is not backbone");
+	  return;
+	}
+    }
+  else   /* Not Shortcut ABR */
+    {
+      if (!OSPF_IS_AREA_ID_BACKBONE (or->u.std.area_id))
+	{
+	  if (IS_DEBUG_OSPF_EVENT)
+	    zlog_info ("ospf_update_network_route(): "
+		       "route is not BB-associated");
+	  return; /* We can update only BB routes */
+	}
+    }
+
+  if (or->cost < cost)
+    {
+      if (IS_DEBUG_OSPF_EVENT)
+	zlog_info ("ospf_update_network_route(): new route is worse");
+      return;
+    }
+
+  if (or->cost == cost)
+    {
+      if (IS_DEBUG_OSPF_EVENT)
+	zlog_info ("ospf_update_network_route(): "
+		   "new route is same distance, adding nexthops");
+      ospf_route_copy_nexthops (or, abr_or->path);
+    }
+
+  if (or->cost > cost)
+    {
+      if (IS_DEBUG_OSPF_EVENT)
+	zlog_info ("ospf_update_network_route(): "
+		   "new route is better, overriding nexthops");
+      ospf_route_subst_nexthops (or, abr_or->path);
+      or->cost = cost;
+
+      if ((ospf_top->abr_type == OSPF_ABR_SHORTCUT) &&
+	  !OSPF_IS_AREA_ID_BACKBONE (or->u.std.area_id))
+	{
+	  or->path_type = OSPF_PATH_INTER_AREA;
+	  or->u.std.area_id = area->area_id;
+#ifdef HAVE_NSSA
+	  or->u.std.external_routing = area->external_routing;
+#endif /* HAVE_NSSA */
+          /* Note that we can do this only in Shortcut ABR mode,
+             because standard ABR must leave the route type and area
+             unchanged
+          */
+        }
+    }
+}
+
+void
+ospf_update_router_route (struct route_table *rtrs, 
+                          struct summary_lsa *lsa,
+                          struct prefix_ipv4 *p,
+                          struct ospf_area *area)
+{
+  struct ospf_route *or, *abr_or, *new_or;
+  struct prefix_ipv4 abr;
+  u_int32_t cost;
+
+  abr.family = AF_INET;
+  abr.prefix = lsa->header.adv_router;
+  abr.prefixlen = IPV4_MAX_BITLEN;
+  apply_mask_ipv4 (&abr);
+
+  abr_or = ospf_find_abr_route (rtrs, &abr, area);
+
+  if (abr_or == NULL)
+    {
+      if (IS_DEBUG_OSPF_EVENT)
+	zlog_info ("ospf_update_router_route(): can't find a route to the ABR");
+      return;
+    }
+
+  cost = abr_or->cost + GET_METRIC (lsa->metric);
+
+  /* First try to find a backbone path,
+     because standard ABR can update only BB-associated paths */
+
+  if ((ospf_top->backbone == NULL) &&
+      (ospf_top->abr_type != OSPF_ABR_SHORTCUT))
+
+     /* no BB area, not Shortcut ABR, exiting */
+     return;
+ 
+  or = ospf_find_asbr_route_through_area (rtrs, p, ospf_top->backbone);
+
+  if (or == NULL)
+    {
+      if (ospf_top->abr_type != OSPF_ABR_SHORTCUT)
+
+         /* route to ASBR through the BB not found
+            the router is not Shortcut ABR, exiting */
+
+          return;
+      else
+	/* We're a Shortcut ABR*/
+	{
+	  /* Let it either add a new router or update the route
+	     through the same (non-BB) area. */
+
+	  new_or = ospf_route_new ();
+	  new_or->type = OSPF_DESTINATION_ROUTER;
+	  new_or->id = lsa->header.id;
+	  new_or->mask = lsa->mask;
+	  new_or->u.std.options = lsa->header.options;
+	  new_or->u.std.origin = (struct lsa_header *)lsa;
+	  new_or->cost = cost;
+	  new_or->u.std.area_id = area->area_id;
+#ifdef HAVE_NSSA
+	  new_or->u.std.external_routing = area->external_routing;
+#endif /* HAVE_NSSA */
+	  new_or->path_type = OSPF_PATH_INTER_AREA;
+	  new_or->u.std.flags = ROUTER_LSA_EXTERNAL;
+	  ospf_ia_router_route (rtrs, p, new_or, abr_or);
+
+          return;
+        }
+    }
+
+  /* At this point the "or" is always bb-associated */
+
+  if (!(or->u.std.flags & ROUTER_LSA_EXTERNAL))
+    {
+      if (IS_DEBUG_OSPF_EVENT)
+	zlog_info ("ospf_upd_router_route(): the remote router is not an ASBR");
+      return;
+    }
+
+  if (or->path_type != OSPF_PATH_INTRA_AREA &&
+      or->path_type != OSPF_PATH_INTER_AREA)
+    return;
+
+  if (or->cost < cost)
+    return;
+
+  else if (or->cost == cost)
+    ospf_route_copy_nexthops (or, abr_or->path);
+
+  else if (or->cost > cost)
+    {
+      ospf_route_subst_nexthops (or, abr_or->path);
+      or->cost = cost;
+
+      /* Even if the ABR runs in Shortcut mode, we can't change
+         the path type and area, because the "or" is always bb-associated
+         at this point and even Shortcut ABR can't change these attributes */
+    }
+}
+
+int
+process_transit_summary_lsa (struct ospf_lsa *l, void *v, int i)
+{
+  struct summary_lsa *sl;
+  struct prefix_ipv4 p;
+  u_int32_t metric;
+  struct ia_args *args;
+
+  if (l == NULL)
+    return 0;
+
+  args = (struct ia_args *) v;
+  sl = (struct summary_lsa *) l->data;
+
+  if (IS_DEBUG_OSPF_EVENT)
+    zlog_info ("process_transit_summaries(): LS ID: %s",
+	       inet_ntoa (l->data->id));
+  metric = GET_METRIC (sl->metric);
+   
+  if (metric == OSPF_LS_INFINITY)
+    {
+      if (IS_DEBUG_OSPF_EVENT)
+	zlog_info ("process_transit_summaries(): metric is infinity, skip");
+      return 0;
+    }
+
+  if (IS_LSA_MAXAGE (l))
+    {
+      if (IS_DEBUG_OSPF_EVENT)
+	zlog_info ("process_transit_summaries(): This LSA is too old");
+      return 0;
+    }
+
+  if (ospf_lsa_is_self_originated (l))
+    { 
+      if (IS_DEBUG_OSPF_EVENT)
+	zlog_info ("process_transit_summaries(): This LSA is mine, skip");
+      return 0;
+    }
+
+  p.family = AF_INET;
+  p.prefix = sl->header.id;
+   
+  if (sl->header.type == OSPF_SUMMARY_LSA)
+    p.prefixlen = ip_masklen (sl->mask);
+  else
+    p.prefixlen = IPV4_MAX_BITLEN;
+      
+  apply_mask_ipv4 (&p);
+
+  if (sl->header.type == OSPF_SUMMARY_LSA)
+    ospf_update_network_route (args->rt, args->rtrs, sl, &p, args->area);
+  else
+    ospf_update_router_route (args->rtrs, sl, &p, args->area);
+ 
+  return 0;
+}
+
+void
+ospf_examine_transit_summaries (struct ospf_area *area,
+                                /* struct ospf_lsdb *lsdb, */
+				struct route_table *lsdb_rt,
+                                struct route_table *rt,
+                                struct route_table *rtrs)
+{
+  struct ia_args args = {rt, rtrs, area};
+
+  /* ospf_lsdb_iterator (lsdb, &args, 0, process_transit_summary_lsa); */
+  foreach_lsa (lsdb_rt, &args, 0, process_transit_summary_lsa);
+}
+
+void
+ospf_ia_routing (struct route_table *rt,
+                 struct route_table *rtrs)
+{
+  struct ospf_area * area;
+
+  if (IS_DEBUG_OSPF_EVENT)
+    zlog_info ("ospf_ia_routing():start");
+
+  if (OSPF_IS_ABR)
+    {
+      listnode node; 
+      struct ospf_area *area;
+
+      switch (ospf_top->abr_type)
+        {
+        case OSPF_ABR_STAND:
+	  if (IS_DEBUG_OSPF_EVENT)
+	    zlog_info ("ospf_ia_routing():Standard ABR");
+
+          if ((area = ospf_top->backbone))
+            {
+              listnode node;
+
+	      if (IS_DEBUG_OSPF_EVENT)
+		{
+		  zlog_info ("ospf_ia_routing():backbone area found");
+		  zlog_info ("ospf_ia_routing():examining summaries");
+		}
+
+              OSPF_EXAMINE_SUMMARIES_ALL (area, rt, rtrs);
+
+	      for (node = listhead (ospf_top->areas); node; nextnode (node))
+                if ((area = getdata (node)) != NULL)
+                  if (area != ospf_top->backbone)
+		    if (ospf_area_is_transit (area))
+		      OSPF_EXAMINE_TRANSIT_SUMMARIES_ALL (area, rt, rtrs);
+            }
+          else
+	    if (IS_DEBUG_OSPF_EVENT)
+	      zlog_info ("ospf_ia_routing():backbone area NOT found");
+          break;
+        case OSPF_ABR_IBM:
+        case OSPF_ABR_CISCO:
+	  if (IS_DEBUG_OSPF_EVENT)
+	    zlog_info ("ospf_ia_routing():Alternative Cisco/IBM ABR");
+          area = ospf_top->backbone; /* Find the BB */
+
+          /* If we have an active BB connection */
+          if (area && ospf_act_bb_connection ())
+            {
+	      if (IS_DEBUG_OSPF_EVENT)
+		{
+		  zlog_info ("ospf_ia_routing(): backbone area found");
+		  zlog_info ("ospf_ia_routing(): examining BB summaries");
+		}
+
+              OSPF_EXAMINE_SUMMARIES_ALL (area, rt, rtrs);
+
+	      for (node = listhead (ospf_top->areas); node; nextnode (node))
+                if ((area = getdata (node)) != NULL)
+                  if (area != ospf_top->backbone)
+		    if (ospf_area_is_transit (area))
+		      OSPF_EXAMINE_TRANSIT_SUMMARIES_ALL (area, rt, rtrs);
+            }
+          else
+            { /* No active BB connection--consider all areas */
+	      if (IS_DEBUG_OSPF_EVENT)
+		zlog_info ("ospf_ia_routing(): "
+			   "Active BB connection not found");
+	      for (node = listhead (ospf_top->areas); node; nextnode (node))
+                if ((area = getdata (node)) != NULL)
+                  OSPF_EXAMINE_SUMMARIES_ALL (area, rt, rtrs);
+            }
+          break;
+        case OSPF_ABR_SHORTCUT:
+	  if (IS_DEBUG_OSPF_EVENT)
+	    zlog_info ("ospf_ia_routing():Alternative Shortcut");
+          area = ospf_top->backbone; /* Find the BB */
+
+          /* If we have an active BB connection */
+          if (area && ospf_act_bb_connection ())
+            {
+	      if (IS_DEBUG_OSPF_EVENT)
+		{
+		  zlog_info ("ospf_ia_routing(): backbone area found");
+		  zlog_info ("ospf_ia_routing(): examining BB summaries");
+		}
+              OSPF_EXAMINE_SUMMARIES_ALL (area, rt, rtrs);
+            }
+
+	  for (node = listhead (ospf_top->areas); node; nextnode (node))
+            if ((area = getdata (node)) != NULL)
+              if (area != ospf_top->backbone)
+		if (ospf_area_is_transit (area) ||
+		    ((area->shortcut_configured != OSPF_SHORTCUT_DISABLE) &&
+		     ((ospf_top->backbone == NULL) ||
+                      ((area->shortcut_configured == OSPF_SHORTCUT_ENABLE) &&
+		       area->shortcut_capability))))
+		  OSPF_EXAMINE_TRANSIT_SUMMARIES_ALL (area, rt, rtrs);
+          break;
+        default:
+          break;
+        }
+    }
+  else 
+    {
+      listnode node;
+
+      if (IS_DEBUG_OSPF_EVENT)
+	zlog_info ("ospf_ia_routing():not ABR, considering all areas");
+
+      for (node = listhead (ospf_top->areas); node; nextnode (node))
+        if ((area = getdata (node)) != NULL)
+          OSPF_EXAMINE_SUMMARIES_ALL (area, rt, rtrs);
+    }
+}