lib/iterate: do not follow CNAME when queried for it

diff --git a/lib/layer/iterate.c b/lib/layer/iterate.c
index 3e08b49338c566095ffea02f385e313204b5fea9..464a2a0eae794ce8ad7ef5dc45c548c4eca2eaa7 100644 (file)
--- a/lib/layer/iterate.c
+++ b/lib/layer/iterate.c
@@ -113,8 +113,8 @@ static void follow_cname_chain(const knot_dname_t **cname, const knot_rrset_t *r
 {
        if (rr->type == KNOT_RRTYPE_CNAME) {
                *cname = knot_cname_name(&rr->rrs);
-       } else {
-               /* Terminate CNAME chain. */
+       } else if (rr->type != KNOT_RRTYPE_RRSIG) {
+               /* Terminate CNAME chain (if not RRSIG). */
                *cname = cur->sname;
        }
 }
@@ -352,10 +352,13 @@ static int process_answer(knot_pkt_t *pkt, struct kr_request *req)
 
        /* Process answer type */
        const knot_pktsection_t *an = knot_pkt_section(pkt, KNOT_ANSWER);
+       bool follow_chain = (query->stype != KNOT_RRTYPE_CNAME);
        const knot_dname_t *cname = query->sname;
        for (unsigned i = 0; i < an->count; ++i) {
+               /* @todo construct a CNAME chain closure and accept all names from that set */ 
                const knot_rrset_t *rr = knot_pkt_rr(an, i);
-               if (!knot_dname_is_equal(rr->owner, cname)) {
+               if (!knot_dname_is_equal(rr->owner, query->sname) &&
+                       !(follow_chain && knot_dname_is_equal(rr->owner, cname))) {
                        continue;
                }
                unsigned hint = 0;
@@ -366,10 +369,12 @@ static int process_answer(knot_pkt_t *pkt, struct kr_request *req)
                if (state == KNOT_STATE_FAIL) {
                        return state;
                }
-               follow_cname_chain(&cname, rr, query);
-               /* Trust only CNAME targets in current cut. */
-               if (!knot_dname_in(query->zone_cut.name, cname)) {
-                       break;
+               /* Follow chain only within current cut. */
+               if (follow_chain) {
+                       follow_cname_chain(&cname, rr, query);
+                       if (!knot_dname_in(query->zone_cut.name, cname)) {
+                               follow_chain = false; 
+                       }
                }
        }
 

diff --git a/lib/layer/rrcache.c b/lib/layer/rrcache.c
index ea474f5fdf317f1b79aeccf3521ae26526e4f234..dde29829e0ee322034acedaaea7a38b038d448fb 100644 (file)
--- a/lib/layer/rrcache.c
+++ b/lib/layer/rrcache.c
@@ -253,11 +253,11 @@ static int stash_answer(struct kr_query *qry, knot_pkt_t *pkt, map_t *stash, mm_
                kr_rrmap_add(stash, rr, pool);
                /* Follow CNAME chain in current cut. */
                if (rr->type == KNOT_RRTYPE_CNAME) {
-                       cname = knot_cname_name(&rr->rrs);
-                       if (!knot_dname_in(qry->zone_cut.name, cname)) {
-                               break;
+                       const knot_dname_t *next_cname = knot_cname_name(&rr->rrs);
+                       if (knot_dname_in(qry->zone_cut.name, next_cname)) {
+                               cname = next_cname;
                        }
-               } else {
+               } else if (rr->type != KNOT_RRTYPE_RRSIG) {
                        cname = qry->sname;
                }
        }