Added previously removed auth check.

- node->prev can contain both delegation points and authoritive nodes, so the check has to be present.

src/knot/nameserver/nsec_proofs.c

@@ -285,6 +285,9 @@ static int ns_put_nsec_wildcard(const knot_zone_contents_t *zone,
 	if (previous == NULL) {
 		previous = knot_zone_contents_find_previous(zone, qname);
 		assert(previous != NULL);
+		while (previous->flags != NODE_FLAGS_AUTH) {
+			previous = previous->prev;
+		}
 	}
 
 	knot_rrset_t rrset = node_rrset(previous, KNOT_RRTYPE_NSEC);
@@ -468,9 +471,11 @@ static int ns_put_nsec_nxdomain(const knot_dname_t *qname,
 
 	// check if we have previous; if not, find one using the tree
 	if (previous == NULL) {
-		/*! \todo Check version. */
 		previous = knot_zone_contents_find_previous(zone, qname);
 		assert(previous != NULL);
+		while (previous->flags != NODE_FLAGS_AUTH) {
+			previous = previous->prev;
+		}
 	}
 
 dbg_ns_exec_verb(

src/knot/zone/zone-contents.c

@@ -213,6 +213,9 @@ static int adjust_pointers(zone_node_t **tnode, void *data)
 		node->flags |= NODE_FLAGS_NONAUTH;
 	} else if (node_rrtype_exists(node, KNOT_RRTYPE_NS) && node != args->zone->apex) {
 		node->flags |= NODE_FLAGS_DELEG;
+	} else {
+		// Default.
+		node->flags = NODE_FLAGS_AUTH;
 	}
 
 	// set pointer to previous node