Merge pull request #20835 from xnumad/nib-route-hide-on-link-prefixes

gnrc/ipv6: `nib route`: hide off-link PLEs

sys/include/net/gnrc/ipv6/nib/ft.h

@@ -112,7 +112,8 @@ void gnrc_ipv6_nib_ft_del(const ipv6_addr_t *dst, unsigned dst_len);
  *
  * The iteration over all forwarding table entries in the NIB includes all
  * entries added via @p gnrc_ipv6_nib_ft_add() and entries that are currently
- * in the Destination Cache, in the Prefix List, and in the Default Router List.
+ * in the Destination Cache, in the Prefix List (only if they're on-link),
+ * and in the Default Router List.
  *
  * Usage example:
  *

sys/net/gnrc/network_layer/ipv6/nib/nib_ft.c

@@ -132,14 +132,26 @@ bool gnrc_ipv6_nib_ft_iter(const ipv6_addr_t *next_hop, unsigned iface,
 
         while ((offl = _nib_offl_iter(offl))) {
             assert(offl->mode != 0);
-            if ((offl->next_hop != NULL) &&
-                ((iface == 0) || (iface == _nib_onl_get_if(offl->next_hop))) &&
-                ((next_hop == NULL) || ipv6_addr_equal(&offl->next_hop->ipv6,
-                                                       next_hop))) {
-                _nib_ft_get(offl, fte);
-                *state = offl;
-                return true;
+            if (offl->next_hop == NULL) {
+                /* 'holey' NIB / dangling reference.
+                 * there is no next hop (not even an interface) */
+                continue;
             }
+            if (offl->mode == _PL && !(offl->flags & _PFX_ON_LINK)) {
+                /* prefix list entry is off-link */
+                continue;
+            }
+            if (iface && iface != _nib_onl_get_if(offl->next_hop)) {
+                /* interface does not match */
+                continue;
+            }
+            if (next_hop && !ipv6_addr_equal(&offl->next_hop->ipv6, next_hop)) {
+                /* next hop does not match */
+                continue;
+            }
+            _nib_ft_get(offl, fte);
+            *state = offl;
+            return true;
         }
         *state = NULL;
     }