replaced add/remove ds6-nbr with an nbr-module controlled update of lladdress to avoid loss of other state information

core/net/ipv6/uip-nd6.c

@@ -136,7 +136,7 @@ static uip_ds6_prefix_t *prefix; /**  Pointer to a prefix list entry */
 /*------------------------------------------------------------------*/
 /* Copy link-layer address from LLAO option to a word-aligned uip_lladdr_t */
 static void
-extract_lladdr_aligned(uip_lladdr_t *dest) {
+extract_lladdr_from_llao_aligned(uip_lladdr_t *dest) {
   if(dest != NULL && nd6_opt_llao != NULL) {
     memcpy(dest, &nd6_opt_llao[UIP_ND6_OPT_DATA_OFFSET], UIP_LLADDR_LEN);
   }
@@ -199,17 +199,29 @@ ns_input(void)
         goto discard;
       } else {
 #endif /*UIP_CONF_IPV6_CHECKS */
+        uip_lladdr_t lladdr_aligned;
+        extract_lladdr_from_llao_aligned(&lladdr_aligned);
         nbr = uip_ds6_nbr_lookup(&UIP_IP_BUF->srcipaddr);
         if(nbr == NULL) {
+<<<<<<< 2e852f758b3fbc18ad30ec75d8c62b5d5238e70a
           uip_lladdr_t lladdr_aligned;
           extract_lladdr_aligned(&lladdr_aligned);
           uip_ds6_nbr_add(&UIP_IP_BUF->srcipaddr, &lladdr_aligned,
 			  0, NBR_STALE, NBR_TABLE_REASON_IPV6_ND, NULL);
+=======
+          uip_ds6_nbr_add(&UIP_IP_BUF->srcipaddr, &lladdr_aligned, 0, NBR_STALE);
+>>>>>>> replaced add/remove ds6-nbr with an nbr-module controlled update of lladdress to avoid loss of other state information
         } else {
-          uip_lladdr_t *lladdr = (uip_lladdr_t *)uip_ds6_nbr_get_ll(nbr);
+          const uip_lladdr_t *lladdr = uip_ds6_nbr_get_ll(nbr);
+          if(lladdr == NULL) {
+            goto discard;
+          }
           if(memcmp(&nd6_opt_llao[UIP_ND6_OPT_DATA_OFFSET],
               lladdr, UIP_LLADDR_LEN) != 0) {
-            memcpy(lladdr, &nd6_opt_llao[UIP_ND6_OPT_DATA_OFFSET], UIP_LLADDR_LEN);
+            if(nbr_table_update_lladdr((const linkaddr_t *)lladdr, (const linkaddr_t *)&lladdr_aligned, 1) == 0) {
+              /* failed to update the lladdr */
+              goto discard;
+            }
             nbr->state = NBR_STALE;
           } else {
             if(nbr->state == NBR_INCOMPLETE) {
@@ -495,10 +507,12 @@ na_input(void)
     if(nbr == NULL) {
       goto discard;
     }
-
     lladdr = uip_ds6_nbr_get_ll(nbr);
+    if(lladdr == NULL) {
+      goto discard;
+    }
     if(nd6_opt_llao != NULL) {
-      is_llchange = lladdr == NULL ||
+      is_llchange =
         memcmp(&nd6_opt_llao[UIP_ND6_OPT_DATA_OFFSET], lladdr,
                UIP_LLADDR_LEN);
     }
@@ -507,17 +521,13 @@ na_input(void)
       if(nd6_opt_llao == NULL) {
         goto discard;
       }
-      extract_lladdr_aligned(&lladdr_aligned);
 
-      /* Remove this neighbor - since it has a NULL MAC address */
+      extract_lladdr_from_llao_aligned(&lladdr_aligned);
-      uip_ds6_nbr_rm(nbr);
+      if(nbr_table_update_lladdr((const linkaddr_t *)lladdr, (const linkaddr_t *)&lladdr_aligned, 1) == 0) {
-      /* Re-add this neighbor - now with a correct MAC address */
+        /* failed to update the lladdr */
-      nbr = uip_ds6_nbr_add(&UIP_ND6_NA_BUF->tgtipaddr,
-                            &lladdr_aligned,
-                            is_router, NBR_STALE);
-      if(nbr == NULL) {
         goto discard;
       }
+
       if(is_solicited) {
         nbr->state = NBR_REACHABLE;
         nbr->nscount = 0;
@@ -529,7 +539,7 @@ na_input(void)
         nbr->state = NBR_STALE;
       }
       nbr->isrouter = is_router;
-    } else {
+    } else { /* NBR is not INCOMPLETE */
       if(!is_override && is_llchange) {
         if(nbr->state == NBR_REACHABLE) {
           nbr->state = NBR_STALE;
@@ -543,15 +553,9 @@ na_input(void)
         if(is_override || !is_llchange || nd6_opt_llao == NULL) {
           if(nd6_opt_llao != NULL && is_llchange) {
             uip_lladdr_t lladdr_aligned;
-            extract_lladdr_aligned(&lladdr_aligned);
+            extract_lladdr_from_llao_aligned(&lladdr_aligned);
-
+            if(nbr_table_update_lladdr((const linkaddr_t *) lladdr, (const linkaddr_t *) &lladdr_aligned, 1) == 0) {
-            /* Remove this neighbor - since it has updated its MAC address */
+              /* failed to update the lladdr */
-            uip_ds6_nbr_rm(nbr);
-            /* Re-add this neighbor - now with a correct (new) MAC address */
-            nbr = uip_ds6_nbr_add(&UIP_ND6_NA_BUF->tgtipaddr,
-                                  &lladdr_aligned,
-                                  is_router, NBR_STALE);
-            if(nbr == NULL) {
               goto discard;
             }
           }
@@ -652,15 +656,19 @@ rs_input(void)
     } else {
 #endif /*UIP_CONF_IPV6_CHECKS */
       uip_lladdr_t lladdr_aligned;
-      extract_lladdr_aligned(&lladdr_aligned);
+      extract_lladdr_from_llao_aligned(&lladdr_aligned);
       if((nbr = uip_ds6_nbr_lookup(&UIP_IP_BUF->srcipaddr)) == NULL) {
         /* we need to add the neighbor */
         uip_ds6_nbr_add(&UIP_IP_BUF->srcipaddr, &lladdr_aligned,
                         0, NBR_STALE, NBR_TABLE_REASON_IPV6_ND, NULL);
       } else {
         /* If LL address changed, set neighbor state to stale */
+        const uip_lladdr_t *lladdr = uip_ds6_nbr_get_ll(nbr);
+        if(lladdr == NULL) {
+          goto discard;
+        }
         if(memcmp(&nd6_opt_llao[UIP_ND6_OPT_DATA_OFFSET],
-                  uip_ds6_nbr_get_ll(nbr), UIP_LLADDR_LEN) != 0) {
+            lladdr, UIP_LLADDR_LEN) != 0) {
           uip_ds6_nbr_t nbr_data = *nbr;
           uip_ds6_nbr_rm(nbr);
           nbr = uip_ds6_nbr_add(&UIP_IP_BUF->srcipaddr, &lladdr_aligned,
@@ -892,18 +900,31 @@ ra_input(void)
       nbr = uip_ds6_nbr_lookup(&UIP_IP_BUF->srcipaddr);
       if(nbr == NULL) {
         uip_lladdr_t lladdr_aligned;
+<<<<<<< 2e852f758b3fbc18ad30ec75d8c62b5d5238e70a
         extract_lladdr_aligned(&lladdr_aligned);
         nbr = uip_ds6_nbr_add(&UIP_IP_BUF->srcipaddr, &lladdr_aligned,
                               1, NBR_STALE, NBR_TABLE_REASON_IPV6_ND, NULL);
+=======
+        extract_lladdr_from_llao_aligned(&lladdr_aligned);
+        nbr = uip_ds6_nbr_add(&UIP_IP_BUF->srcipaddr, &lladdr_aligned, 1, NBR_STALE);
+>>>>>>> replaced add/remove ds6-nbr with an nbr-module controlled update of lladdress to avoid loss of other state information
       } else {
-        uip_lladdr_t *lladdr = (uip_lladdr_t *)uip_ds6_nbr_get_ll(nbr);
+        uip_lladdr_t lladdr_aligned;
+        extract_lladdr_from_llao_aligned(&lladdr_aligned);
+        const uip_lladdr_t *lladdr = uip_ds6_nbr_get_ll(nbr);
+        if(lladdr == NULL) {
+          goto discard;
+        }
         if(nbr->state == NBR_INCOMPLETE) {
           nbr->state = NBR_STALE;
         }
         if(memcmp(&nd6_opt_llao[UIP_ND6_OPT_DATA_OFFSET],
                   lladdr, UIP_LLADDR_LEN) != 0) {
-          memcpy(lladdr, &nd6_opt_llao[UIP_ND6_OPT_DATA_OFFSET],
+          /* change of link layer address */
-                 UIP_LLADDR_LEN);
+          if(nbr_table_update_lladdr((const linkaddr_t *)lladdr, (const linkaddr_t *)&lladdr_aligned, 1) == 0) {
+            /* failed to update the lladdr */
+            goto discard;
+          }
           nbr->state = NBR_STALE;
         }
         nbr->isrouter = 1;

core/net/nbr-table.c

@@ -178,6 +178,26 @@ nbr_set_bit(uint8_t *bitmap, nbr_table_t *table, nbr_table_item_t *item, int val
   return 0;
 }
 /*---------------------------------------------------------------------------*/
+static void
+remove_key(nbr_table_key_t *least_used_key)
+{
+  int i;
+  for(i = 0; i < MAX_NUM_TABLES; i++) {
+    if(all_tables[i] != NULL && all_tables[i]->callback != NULL) {
+      /* Call table callback for each table that uses this item */
+      nbr_table_item_t *removed_item = item_from_key(all_tables[i], least_used_key);
+      if(nbr_get_bit(used_map, all_tables[i], removed_item) == 1) {
+        all_tables[i]->callback(removed_item);
+      }
+    }
+  }
+  /* Empty used map */
+  used_map[index_from_key(least_used_key)] = 0;
+  /* Remove neighbor from list */
+  list_remove(nbr_table_keys, least_used_key);
+  /* Return associated key */
+}
+
 static nbr_table_key_t *
 nbr_table_allocate(nbr_table_reason_t reason, void *data)
 {
@@ -253,21 +273,7 @@ nbr_table_allocate(nbr_table_reason_t reason, void *data)
       return NULL;
     } else {
       /* Reuse least used item */
-      int i;
+      remove_key(least_used_key);
-      for(i = 0; i<MAX_NUM_TABLES; i++) {
-        if(all_tables[i] != NULL && all_tables[i]->callback != NULL) {
-          /* Call table callback for each table that uses this item */
-          nbr_table_item_t *removed_item = item_from_key(all_tables[i], least_used_key);
-          if(nbr_get_bit(used_map, all_tables[i], removed_item) == 1) {
-            all_tables[i]->callback(removed_item);
-          }
-        }
-      }
-      /* Empty used map */
-      used_map[index_from_key(least_used_key)] = 0;
-      /* Remove neighbor from list */
-      list_remove(nbr_table_keys, least_used_key);
-      /* Return associated key */
       return least_used_key;
     }
   }
@@ -416,6 +422,39 @@ nbr_table_get_lladdr(nbr_table_t *table, const void *item)
   return key != NULL ? &key->lladdr : NULL;
 }
 /*---------------------------------------------------------------------------*/
+/* Update link-layer address of an item */
+int
+nbr_table_update_lladdr(const linkaddr_t *old_addr, const linkaddr_t *new_addr,
+                        int remove_if_duplicate)
+{
+  int index;
+  int new_index;
+  nbr_table_key_t *key;
+  index = index_from_lladdr(old_addr);
+  if(index == -1) {
+    /* Failure to change since there is nothing to change. */
+    return 0;
+  }
+  if((new_index = index_from_lladdr(new_addr)) != -1) {
+    /* check if it is a change or not - do not remove / fail if same */
+    if(new_index == index) {
+      return 1;
+    }
+    /* This new entry already exists - failure! - remove if requested. */
+    if(remove_if_duplicate) {
+      remove_key(key_from_index(index));
+    }
+    return 0;
+  }
+  key = key_from_index(index);
+  /**
+   * Copy the new lladdr into the key - since we know that there is no
+   * conflicting entry.
+   */
+  memcpy(&key->lladdr, new_addr, sizeof(linkaddr_t));
+  return 1;
+}
+/*---------------------------------------------------------------------------*/
 #if DEBUG
 static void
 print_table()

core/net/nbr-table.h

@@ -109,6 +109,7 @@ int nbr_table_unlock(nbr_table_t *table, nbr_table_item_t *item);
 /** \name Neighbor tables: address manipulation */
 /** @{ */
 linkaddr_t *nbr_table_get_lladdr(nbr_table_t *table, const nbr_table_item_t *item);
+int nbr_table_update_lladdr(const linkaddr_t *old_addr, const linkaddr_t *new_addr, int remove_if_duplicate);
 /** @} */
 
 #endif /* NBR_TABLE_H_ */