iterate: simplified qname m12n

diff --git a/lib/layer/iterate.c b/lib/layer/iterate.c
index e653443ea17501020aa3720f729896048fe9cbe5..4b2abe149f171b1c1f08b7444f6e617ea5d244e2 100644 (file)
--- a/lib/layer/iterate.c
+++ b/lib/layer/iterate.c
@@ -154,10 +154,15 @@ static int resolve_auth(knot_pkt_t *pkt, struct kr_layer_param *param)
                return KNOT_NS_PROC_FAIL;
        }
 
-       /* Authoritative response for min QNAME => disable and retry */
-       bool is_minimized = (knot_pkt_qtype(pkt) != cur->stype &&
-                            !knot_dname_is_equal(knot_pkt_qname(pkt), cur->sname));
-       if (is_minimized && knot_wire_get_rcode(pkt->wire) == KNOT_RCODE_NOERROR) {
+       /* Authoritative response for minimized QNAME.
+        * NODATA   => may be empty non-terminal, retry (found zone cut)
+        * NOERROR  => found zone cut, retry
+        * NXDOMAIN => parent is zone cut, terminate
+        */
+       const knot_pktsection_t *an = knot_pkt_section(pkt, KNOT_ANSWER);
+       bool is_minimized = (!knot_dname_is_equal(knot_pkt_qname(pkt), cur->sname));
+       bool is_noerror = (knot_wire_get_rcode(pkt->wire) == KNOT_RCODE_NOERROR);
+       if (is_minimized && is_noerror && an->count == 0) {
                cur->flags |= QUERY_NO_MINIMIZE;
                return KNOT_NS_PROC_DONE;
        }
@@ -208,11 +213,16 @@ static int resolve_error(knot_pkt_t *pkt, struct kr_layer_param *param, int errc
        return KNOT_NS_PROC_FAIL;
 }
 
-/*! \brief Return minimized QNAME for current zone cut. */
-static const knot_dname_t *minimized_qname(struct kr_query *query, struct kr_zonecut *cut)
+/*! \brief Return minimized QNAME/QTYPE for current zone cut. */
+static const knot_dname_t *minimized_qname(struct kr_query *query, struct kr_zonecut *cut, uint16_t *qtype)
 {
-       /* Minimize name to contain current zone cut + 1 label. */
+       /* Minimization disabled. */
        const knot_dname_t *qname = query->sname;
+       if (query->flags & QUERY_NO_MINIMIZE) {
+               return qname;
+       }
+
+       /* Minimize name to contain current zone cut + 1 label. */
        int cut_labels = knot_dname_labels(cut->name, NULL);
        int qname_labels = knot_dname_labels(qname, NULL);
        while(qname_labels > cut_labels + 1) {
@@ -220,6 +230,11 @@ static const knot_dname_t *minimized_qname(struct kr_query *query, struct kr_zon
                qname_labels -= 1;
        }
 
+       /* Hide QTYPE if minimized. */
+       if (qname != query->sname) {
+               *qtype = KNOT_RRTYPE_NS;
+       }
+
        return qname;
 }
 
@@ -231,19 +246,13 @@ static bool is_answer_to_query(const knot_pkt_t *answer, struct kr_rplan *rplan)
                return -1;
        }
 
-       uint16_t expect_qtype = expect->stype;
-       const knot_dname_t *expect_qname = expect->sname;
-       if (!expect->flags & QUERY_NO_MINIMIZE) {
-               expect_qname = minimized_qname(expect, &rplan->zone_cut);
-               if (expect_qname != expect->sname) {
-                       expect_qtype = KNOT_RRTYPE_NS;
-               }
-       }
+       uint16_t qtype = expect->stype;
+       const knot_dname_t *qname = minimized_qname(expect, &rplan->zone_cut, &qtype);
 
        return expect->id      == knot_wire_get_id(answer->wire) &&
               expect->sclass  == knot_pkt_qclass(answer) &&
-              expect_qtype    == knot_pkt_qtype(answer) &&
-              knot_dname_is_equal(expect_qname, knot_pkt_qname(answer));
+              qtype           == knot_pkt_qtype(answer) &&
+              knot_dname_is_equal(qname, knot_pkt_qname(answer));
 }
 
 /* State-less single resolution iteration step, not needed. */
@@ -268,14 +277,8 @@ static int prepare_query(knot_layer_t *ctx, knot_pkt_t *pkt)
 
        /* Minimize QNAME (if possible). */
        struct kr_zonecut *zone_cut = &param->rplan->zone_cut;
-       const knot_dname_t *qname = cur->sname;
        uint16_t qtype = cur->stype;
-       if (!(cur->flags & QUERY_NO_MINIMIZE)) {
-               qname = minimized_qname(cur, zone_cut);
-               if (qname != cur->sname) {
-                       qtype = KNOT_RRTYPE_NS;
-               }
-       }
+       const knot_dname_t *qname = minimized_qname(cur, zone_cut, &qtype);
 
        /* Form a query for the authoritative. */
        knot_pkt_clear(pkt);