- Implement RPZ CNAME target wildcard synthesis

diff --git a/services/localzone.c b/services/localzone.c
index bf10438254b9ed1e576fcc9a1260aec5bcf3f56b..4c094cc9dd1b6668fbf28f62d1c575dd07577462 100644 (file)
--- a/services/localzone.c
+++ b/services/localzone.c
@@ -1407,17 +1407,70 @@ local_data_answer(struct local_zone* z, struct module_env* env,
                lz_type == local_zone_inform_redirect) &&
                qinfo->qtype != LDNS_RR_TYPE_CNAME &&
                lr->rrset->rk.type == htons(LDNS_RR_TYPE_CNAME)) {
+               uint8_t* ctarget;
+               size_t ctargetlen = 0;
+
                qinfo->local_alias =
                        regional_alloc_zero(temp, sizeof(struct local_rrset));
                if(!qinfo->local_alias)
                        return 0; /* out of memory */
-               qinfo->local_alias->rrset =
-                       regional_alloc_init(temp, lr->rrset, sizeof(*lr->rrset));
+               qinfo->local_alias->rrset = regional_alloc_init(
+                       temp, lr->rrset, sizeof(*lr->rrset));
                if(!qinfo->local_alias->rrset)
                        return 0; /* out of memory */
-               /* TODO local_alias->rrset change cnam etarget */
                qinfo->local_alias->rrset->rk.dname = qinfo->qname;
                qinfo->local_alias->rrset->rk.dname_len = qinfo->qname_len;
+               get_cname_target(lr->rrset, &ctarget, &ctargetlen);
+               if(!ctargetlen)
+                       return 0; /* invalid cname */
+               if(dname_is_wild(ctarget)) {
+                       /* synthesize cname target */
+                       struct packed_rrset_data* d;
+                       uint8_t newtarget[LDNS_MAX_DOMAINLEN];
+                       /* -3 for wildcard label and root label from qname */
+                       size_t newtargetlen = qinfo->qname_len + ctargetlen - 3;
+
+                       log_assert(ctargetlen >= 3);
+                       log_assert(qinfo->qname_len >= 1);
+
+                       if(newtargetlen > LDNS_MAX_DOMAINLEN) {
+                               qinfo->local_alias = NULL;
+                               local_error_encode(qinfo, env, edns, repinfo,
+                                       buf, temp, LDNS_RCODE_YXDOMAIN,
+                                       (LDNS_RCODE_YXDOMAIN|BIT_AA));
+                               return 1;
+                       }
+                       memset(&qinfo->local_alias->rrset->entry, 0,
+                               sizeof(qinfo->local_alias->rrset->entry));
+                       qinfo->local_alias->rrset->entry.key =
+                               qinfo->local_alias->rrset;
+                       qinfo->local_alias->rrset->entry.hash =
+                               rrset_key_hash(&qinfo->local_alias->rrset->rk);
+                       d = (struct packed_rrset_data*)regional_alloc_zero(temp,
+                               sizeof(struct packed_rrset_data) + sizeof(size_t) +
+                               sizeof(uint8_t*) + sizeof(time_t) + sizeof(uint16_t)
+                               + newtargetlen);
+                       if(!d)
+                               return 0; /* out of memory */
+                       qinfo->local_alias->rrset->entry.data = d;
+                       d->ttl = 0; /* 0 for synthesized CNAME TTL */
+                       d->count = 1;
+                       d->rrsig_count = 0;
+                       d->trust = rrset_trust_ans_noAA;
+                       d->rr_len = (size_t*)((uint8_t*)d +
+                               sizeof(struct packed_rrset_data));
+                       d->rr_len[0] = newtargetlen + sizeof(uint16_t);
+                       packed_rrset_ptr_fixup(d);
+                       d->rr_ttl[0] = d->ttl;
+                       sldns_write_uint16(d->rr_data[0], newtargetlen);
+                       /* write qname */
+                       memmove(d->rr_data[0] + sizeof(uint16_t), qinfo->qname,
+                               qinfo->qname_len - 1);
+                       /* write cname target wilcard wildcard label */
+                       memmove(d->rr_data[0] + sizeof(uint16_t) +
+                               qinfo->qname_len - 1, ctarget + 2,
+                               ctargetlen - 2);
+               }
                return 1;
        }
        if(lz_type == local_zone_redirect ||