Change ARO routes to be direct route instead of on-link

This will make the routing logic to consider other routes if the
direct ARO route is not working.

If the link recovers it should start using it.

Author: Mika Tervonen

source/6LoWPAN/ND/nd_router_object.c

@@ -839,13 +839,20 @@ buffer_t *nd_dar_parse(buffer_t *buf, protocol_interface_info_entry_t *cur_inter
 #ifdef HAVE_6LOWPAN_ROUTER
 static void nd_update_registration(protocol_interface_info_entry_t *cur_interface, ipv6_neighbour_t *neigh, const aro_t *aro)
 {
+    uint8_t ll64[16];
+
+    memcpy(ll64, ADDR_LINK_LOCAL_PREFIX, 8);
+    memcpy(&ll64[8], aro->eui64, 8);
+    ll64[8] ^= 2;
+
+
     /* We are about to send an ARO response - update our Neighbour Cache accordingly */
     if (aro->status == ARO_SUCCESS && aro->lifetime != 0) {
         neigh->type = IP_NEIGHBOUR_REGISTERED;
         neigh->lifetime = aro->lifetime * UINT32_C(60);
         ipv6_neighbour_set_state(&cur_interface->ipv6_neighbour_cache, neigh, IP_NEIGHBOUR_STALE);
         /* Register with 2 seconds off the lifetime - don't want the NCE to expire before the route */
-        ipv6_route_add(neigh->ip_address, 128, cur_interface->id, NULL, ROUTE_ARO, neigh->lifetime - 2, 0);
+        ipv6_route_add(neigh->ip_address, 128, cur_interface->id, ll64, ROUTE_ARO, neigh->lifetime - 2, 0);
 
         /* We need to know peer is a host before publishing - this needs MLE. Not yet established
          * what to do without MLE - might need special external/non-external prioritisation at root.
@@ -864,19 +871,24 @@ static void nd_update_registration(protocol_interface_info_entry_t *cur_interfac
         neigh->type = IP_NEIGHBOUR_TENTATIVE;
         neigh->lifetime = 2;
         ipv6_neighbour_set_state(&cur_interface->ipv6_neighbour_cache, neigh, IP_NEIGHBOUR_STALE);
-        ipv6_route_add(neigh->ip_address, 128, cur_interface->id, NULL, ROUTE_ARO, 4, 0);
+        ipv6_route_add(neigh->ip_address, 128, cur_interface->id, ll64, ROUTE_ARO, 4, 0);
         rpl_control_unpublish_address(protocol_6lowpan_rpl_domain, neigh->ip_address);
     }
 }
 
 void nd_remove_registration(protocol_interface_info_entry_t *cur_interface, addrtype_t ll_type, const uint8_t *ll_address)
 {
+    uint8_t ll64[16];
+
+    memcpy(ll64, ADDR_LINK_LOCAL_PREFIX, 8);
 
     ns_list_foreach_safe(ipv6_neighbour_t, cur, &cur_interface->ipv6_neighbour_cache.list) {
         if ((cur->type == IP_NEIGHBOUR_REGISTERED
                 || cur->type == IP_NEIGHBOUR_TENTATIVE)
                 && ipv6_neighbour_ll_addr_match(cur, ll_type, ll_address)) {
-            ipv6_route_delete(cur->ip_address, 128, cur_interface->id, NULL,
+            memcpy(&ll64[8], ipv6_neighbour_eui64(&cur_interface->ipv6_neighbour_cache, cur), 8);
+            ll64[8] ^= 2;
+            ipv6_route_delete(cur->ip_address, 128, cur_interface->id,ll64,
                               ROUTE_ARO);
             ipv6_neighbour_entry_remove(&cur_interface->ipv6_neighbour_cache,
                                         cur);