Don't crash when attempting to read path->oi->ifp if oi doesn't exist any
more. I'm not sure if this read should be attempted at all, but I'm trying
to keep code safe AND stable.
diff --git a/ospfd/ChangeLog b/ospfd/ChangeLog
index 9dafb96..b2a5ad2 100644
--- a/ospfd/ChangeLog
+++ b/ospfd/ChangeLog
@@ -1,3 +1,7 @@
+2004-02-11 Hasso Tepper <hasso@estpak.ee>
+	* ospf_interface.c, ospf_zebra.c: Don't attempt to read path->oi->ifp
+	  if oi doesn't exist any more.
+
 2004-02-11 Vadim Suraev <vadim.suraev@terayon.com>
 	* ospf_packet.c (ospf_ls_upd): Router should flush received network
 	  LSA if it was originated with older router-id ([zebra 14710] #6).
diff --git a/ospfd/ospf_interface.c b/ospfd/ospf_interface.c
index 2afe19e..2f94b43 100644
--- a/ospfd/ospf_interface.c
+++ b/ospfd/ospf_interface.c
@@ -371,6 +371,23 @@
 }
 
 struct ospf_interface *
+ospf_if_exists (struct ospf_interface *oic)
+{ 
+  listnode node;
+  struct ospf *ospf;
+  struct ospf_interface *oi;
+
+  ospf = ospf_lookup ();
+
+  for (node = listhead (ospf->oiflist); node; nextnode (node))
+  {
+    if (((oi = getdata (node)) != NULL) && (oi == oic))
+      return oi;
+  }
+  return NULL;
+}
+
+struct ospf_interface *
 ospf_if_lookup_by_local_addr (struct ospf *ospf,
 			      struct interface *ifp, struct in_addr address)
 {
diff --git a/ospfd/ospf_interface.h b/ospfd/ospf_interface.h
index 6dc01ae..6f54618 100644
--- a/ospfd/ospf_interface.h
+++ b/ospfd/ospf_interface.h
@@ -190,26 +190,32 @@
   u_int32_t discarded;		/* discarded input count by error. */
   u_int32_t state_change;	/* Number of status change. */
 
-  u_int full_nbrs;
+  u_int32_t full_nbrs;
 };
 
 /* Prototypes. */
 char *ospf_if_name (struct ospf_interface *);
-struct ospf_interface *ospf_if_new ();
+struct ospf_interface *ospf_if_new (struct ospf *, struct interface *,
+				    struct prefix *);
 void ospf_if_cleanup (struct ospf_interface *);
 void ospf_if_free (struct ospf_interface *);
 int ospf_if_up (struct ospf_interface *);
 int ospf_if_down (struct ospf_interface *);
 
 int ospf_if_is_up (struct ospf_interface *);
+struct ospf_interface *ospf_if_exists (struct ospf_interface *);
 struct ospf_interface *ospf_if_lookup_by_name (char *);
-struct ospf_interface *ospf_if_lookup_by_local_addr (struct interface *, struct in_addr);
-struct ospf_interface *ospf_if_lookup_by_prefix (struct prefix_ipv4 *);
-struct ospf_interface *ospf_if_addr_local (struct in_addr src);
-struct ospf_interface *ospf_if_lookup_recv_interface (struct in_addr src);
-struct ospf_interface *ospf_if_is_configured (struct in_addr *);
+struct ospf_interface *ospf_if_lookup_by_local_addr (struct ospf *,
+						     struct interface *,
+						     struct in_addr);
+struct ospf_interface *ospf_if_lookup_by_prefix (struct ospf *,
+						 struct prefix_ipv4 *);
+struct ospf_interface *ospf_if_addr_local (struct in_addr);
+struct ospf_interface *ospf_if_lookup_recv_if (struct ospf *, struct in_addr);
+struct ospf_interface *ospf_if_is_configured (struct ospf *, struct in_addr *);
 
-struct ospf_if_params *ospf_lookup_if_params (struct interface *, struct in_addr);
+struct ospf_if_params *ospf_lookup_if_params (struct interface *,
+					      struct in_addr);
 struct ospf_if_params *ospf_get_if_params (struct interface *, struct in_addr);
 void ospf_del_if_params (struct ospf_if_params *);
 void ospf_free_if_params (struct interface *, struct in_addr);
@@ -224,22 +230,21 @@
 int ospf_if_get_output_cost (struct ospf_interface *);
 void ospf_if_recalculate_output_cost (struct interface *);
 
-struct ospf_interface *ospf_vl_new (struct ospf_vl_data *);
+struct ospf_interface *ospf_vl_new (struct ospf *, struct ospf_vl_data *);
 struct ospf_vl_data *ospf_vl_data_new (struct ospf_area *, struct in_addr);
 struct ospf_vl_data *ospf_vl_lookup (struct ospf_area *, struct in_addr);
 void ospf_vl_data_free (struct ospf_vl_data *);
-void ospf_vl_add (struct ospf_vl_data *);
-void ospf_vl_delete (struct ospf_vl_data *);
+void ospf_vl_add (struct ospf *, struct ospf_vl_data *);
+void ospf_vl_delete (struct ospf *, struct ospf_vl_data *);
 void ospf_vl_up_check (struct ospf_area *, struct in_addr, struct vertex *);
-void ospf_vl_unapprove ();
-void ospf_vl_shut_unapproved ();
+void ospf_vl_unapprove (struct ospf *);
+void ospf_vl_shut_unapproved (struct ospf *);
 int ospf_full_virtual_nbrs (struct ospf_area *);
 int ospf_vls_in_area (struct ospf_area *);
 
 struct crypt_key *ospf_crypt_key_lookup (list, u_char);
 struct crypt_key *ospf_crypt_key_new ();
 void ospf_crypt_key_add (list, struct crypt_key *);
-int ospf_crypt_key_delete (list, u_char key_id);
-
+int ospf_crypt_key_delete (list, u_char);
 
 #endif /* _ZEBRA_OSPF_INTERFACE_H */
diff --git a/ospfd/ospf_zebra.c b/ospfd/ospf_zebra.c
index ea90c84..06916ae 100644
--- a/ospfd/ospf_zebra.c
+++ b/ospfd/ospf_zebra.c
@@ -429,7 +429,7 @@
               nexthop = &path->nexthop;
               api.nexthop = &nexthop;
             }
-          else if (path->oi->ifp)
+          else if (ospf_if_exists(path->oi) && (path->oi->ifp))
             {
               SET_FLAG (api.message, ZAPI_MESSAGE_NEXTHOP);
               api.ifindex_num = 1;