layer/iterate: change the order of records in the answer when CNAME refers to the...

diff --git a/lib/layer/iterate.c b/lib/layer/iterate.c
index c7ebb2c9b8fd23addd79e9635d248c35d6592b90..30c71ae3c42b9e0554d0d542a36563e87dbc2c33 100644 (file)
--- a/lib/layer/iterate.c
+++ b/lib/layer/iterate.c
@@ -469,6 +469,44 @@ static int process_referral_answer(knot_pkt_t *pkt, struct kr_request *req)
        return state == kr_ok() ? KR_STATE_DONE : KR_STATE_FAIL;
 }
 
+static int process_final(knot_pkt_t *pkt, struct kr_request *req,
+                        const knot_dname_t *cname)
+{
+       const int pkt_class = kr_response_classify(pkt);
+       struct kr_query *query = req->current_query;
+       ranked_rr_array_t *array = &req->answ_selected;
+       for (size_t i = 0; i < array->len; ++i) {
+               const knot_rrset_t *rr = array->at[i]->rr;
+               if (!knot_dname_is_equal(rr->owner, cname)) {
+                       continue;
+               }
+               if ((rr->rclass != query->sclass) ||
+                   (rr->type != query->stype)) {
+                       continue;
+               }
+               const bool to_wire = ((pkt_class & (PKT_NXDOMAIN|PKT_NODATA)) != 0);
+               const int state = pick_authority(pkt, req, to_wire);
+               if (state != kr_ok()) {
+                       return KR_STATE_FAIL;
+               }
+               if (!array->at[i]->to_wire) {
+                       const size_t last_idx = array->len - 1;
+                       size_t j = i;
+                       ranked_rr_array_entry_t *entry = array->at[i];
+                       /* Relocate record to the end, after current cname */
+                       while (j < last_idx) {
+                               array->at[j] = array->at[j + 1];
+                               ++j;
+                       }
+                       array->at[last_idx] = entry;
+                       entry->to_wire = true;
+               }
+               finalize_answer(pkt, query, req);
+               return KR_STATE_DONE;
+       }
+       return kr_ok();
+}
+
 static int process_answer(knot_pkt_t *pkt, struct kr_request *req)
 {
        struct kr_query *query = req->current_query;
@@ -509,26 +547,9 @@ static int process_answer(knot_pkt_t *pkt, struct kr_request *req)
                /* Check if target record has been already copied */
                query->flags |= QUERY_CNAME;
                if (is_final) {
-                       for (size_t i = 0; i < req->answ_selected.len; ++i) {
-                               const knot_rrset_t *rr = req->answ_selected.at[i]->rr;
-                               if (!knot_dname_is_equal(rr->owner, cname)) {
-                                       continue;
-                               }
-                               if ((rr->rclass != query->sclass) ||
-                                   (rr->type != query->stype)) {
-                                       continue;
-                               }
-                               bool to_wire = ((pkt_class & (PKT_NXDOMAIN|PKT_NODATA)) != 0);
-                               state = pick_authority(pkt, req, to_wire);
-                               if (state != kr_ok()) {
-                                       return KR_STATE_FAIL;
-                               }
-                               if (!req->answ_selected.at[i]->to_wire) {
-                                       /* TODO relocate this record at the end */
-                                       req->answ_selected.at[i]->to_wire = true;
-                               }
-                               finalize_answer(pkt, query, req);
-                               return KR_STATE_DONE;
+                       state = process_final(pkt, req, cname);
+                       if (state != kr_ok()) {
+                               return state;
                        }
                }
                VERBOSE_MSG("<= cname chain, following\n");