- Allow TTL refresh of expired error responses.

diff --git a/iterator/iterator.c b/iterator/iterator.c
index 751179496dbb4308d1c75db4a12af223600e1362..a6e0b26ce778db1dd51c4f3b138f26105adf2f7f 100644 (file)
--- a/iterator/iterator.c
+++ b/iterator/iterator.c
@@ -320,20 +320,35 @@ error_response_cache(struct module_qstate* qstate, int id, int rcode)
                        if((msg=msg_cache_lookup(qstate->env,
                                qstate->qinfo.qname, qstate->qinfo.qname_len,
                                qstate->qinfo.qtype, qstate->qinfo.qclass,
-                               qstate->query_flags, 0,
-                               qstate->env->cfg->serve_expired_ttl_reset))
-                               != NULL) {
+                               qstate->query_flags, 0, 1)) != NULL) {
+                               struct reply_info* rep =
+                                       (struct reply_info*)msg->entry.data;
                                if(qstate->env->cfg->serve_expired_ttl_reset) {
-                                       struct reply_info* rep =
-                                               (struct reply_info*)msg->entry.data;
                                        if(rep && *qstate->env->now +
                                                qstate->env->cfg->serve_expired_ttl  >
                                                rep->serve_expired_ttl) {
+                                               verbose(VERB_ALGO, "reset "
+                                                       "serve-expired-ttl for "
+                                                       "error response in "
+                                                       "cache");
                                                rep->serve_expired_ttl =
                                                        *qstate->env->now +
                                                        qstate->env->cfg->serve_expired_ttl;
                                        }
                                }
+                               /* if the expired record is an error response
+                                * refresh for another NORR_TTL */
+                               if(rep && *qstate->env->now > rep->ttl &&
+                                       (FLAGS_GET_RCODE(rep->flags) !=
+                                       LDNS_RCODE_NOERROR &&
+                                       FLAGS_GET_RCODE(rep->flags) !=
+                                       LDNS_RCODE_NXDOMAIN &&
+                                       FLAGS_GET_RCODE(rep->flags) !=
+                                       LDNS_RCODE_YXDOMAIN)) {
+                                       verbose(VERB_ALGO, "refresh TTL for "
+                                               "error response in cache");
+                                       rep->ttl = *qstate->env->now + NORR_TTL;
+                               }
                                lock_rw_unlock(&msg->entry.lock);
                                return error_response(qstate, id, rcode);
                        }