cache: fix CNAME on DS query

diff --git a/lib/cache.c b/lib/cache.c
index b65dc694d41eeb5b8f888b01e3a3d42049a97668..603e93bbd0569776e04360de63ea80494602eb39 100644 (file)
--- a/lib/cache.c
+++ b/lib/cache.c
@@ -363,12 +363,6 @@ static int cache_peek_real(kr_layer_t *ctx, knot_pkt_t *pkt)
 
        /** 1b. otherwise, find the longest prefix NS/xNAME (with OK time+rank). [...] */
        k->zname = qry->sname;
-       if (qry->stype == KNOT_RRTYPE_DS) { /* DS is parent-side. */
-               k->zname = knot_wire_next_label(k->zname, NULL);
-               if (!k->zname) {
-                       return ctx->state; /* can't go above root */
-               }
-       }
        kr_dname_lf(k->buf, k->zname, false); /* LATER(optim.): probably remove */
        const knot_db_val_t val_cut = closest_NS(ctx, k);
        if (!val_cut.data) {
@@ -966,9 +960,6 @@ static knot_db_val_t closest_NS(kr_layer_t *ctx, struct key *k)
 
        int zlf_len = k->buf[0];
 
-       /* FIXME re-review:
-        *      - exact_match for DS; probably start with false already
-        */
        uint8_t rank_min = KR_RANK_INSECURE | KR_RANK_AUTH;
        // LATER(optim): if stype is NS, we check the same value again
        bool exact_match = true;
@@ -999,20 +990,25 @@ static knot_db_val_t closest_NS(kr_layer_t *ctx, struct key *k)
                        switch (type) {
                        case 0:
                                type = KNOT_RRTYPE_NS;
-                               if (!eh_orig->has_ns) continue;
+                               if (!eh_orig->has_ns
+                                   /* On a zone cut we want DS from the parent zone. */
+                                   || (exact_match && qry->stype == KNOT_RRTYPE_DS)) {
+                                       continue;
+                               }
                                break;
                        case KNOT_RRTYPE_NS:
                                type = KNOT_RRTYPE_CNAME;
                                /* CNAME is interesting only if we
-                                * directly hit the name that was asked */
-                               if (!exact_match || !eh_orig->has_cname)
+                                * directly hit the name that was asked.
+                                * Note that we want it even in the DS case. */
+                               if (!eh_orig->has_cname || !exact_match)
                                        continue;
                                break;
                        case KNOT_RRTYPE_CNAME:
                                type = KNOT_RRTYPE_DNAME;
                                /* DNAME is interesting only if we did NOT
-                                * directly hit the name that was asked */
-                               if (exact_match || !eh_orig->has_dname)
+                                * directly hit the name that was asked. */
+                               if (!eh_orig->has_dname || exact_match)
                                        continue;
                                break;
                        default: