diff --git a/ospf6d/ospf6_route.h b/ospf6d/ospf6_route.h
index 333b2ce..069502f 100644
--- a/ospf6d/ospf6_route.h
+++ b/ospf6d/ospf6_route.h
@@ -215,6 +215,11 @@
 #define ospf6_linkstate_prefix_id(x) \
   (*(u_int32_t *)(&(x)->u.prefix6.s6_addr[4]))
 
+#define ID_IN_PREFIX(x) \
+  (*(u_int32_t *)(&(x)->u.prefix6.s6_addr[0]))
+#define ADV_ROUTER_IN_PREFIX(x) \
+  (*(u_int32_t *)(&(x)->u.prefix6.s6_addr[4]))
+
 /* Function prototype */
 void ospf6_linkstate_prefix (u_int32_t adv_router, u_int32_t id,
                              struct prefix *prefix);