diff --git a/NEWS b/NEWS index 813e6c89beabb30b893323b1ee309fc04163cb6b..b296d9a71d6c0a63c8325ff9ae76539756ce0478 100644 --- a/NEWS +++ b/NEWS @@ -1,6 +1,11 @@ Knot Resolver 5.3.2 (2021-0m-dd) ================================ +Security +-------- +- validator: fix 5.3.1 regression on over-limit NSEC3 edge case (!1169) + Assertion might be triggered by query/answer, potentially DoS. + Improvements ------------ - cache: improve handling write errors from LMDB (!1159) diff --git a/lib/dnssec/nsec3.c b/lib/dnssec/nsec3.c index e9e536a3c85c3267a841b6dd66179cc5fc316b6d..f3a48c06049634dcff8efbbd5d8a2a14f750f7c9 100644 --- a/lib/dnssec/nsec3.c +++ b/lib/dnssec/nsec3.c @@ -596,6 +596,13 @@ int kr_nsec3_wildcard_answer_response_check(const knot_pkt_t *pkt, knot_section_ if (rrset->type != KNOT_RRTYPE_NSEC3) { continue; } + if (knot_nsec3_iters(rrset->rrs.rdata) > KR_NSEC3_MAX_ITERATIONS) { + /* Avoid hashing with too many iterations. + * If we get here, the `sname` wildcard probably ends up bogus, + * but it gets downgraded to KR_RANK_INSECURE when validator + * gets to verifying one of these over-limit NSEC3 RRs. */ + continue; + } int ret = covers_name(&flags, rrset, sname); if (ret != 0) { return ret; diff --git a/lib/dnssec/nsec3.h b/lib/dnssec/nsec3.h index 1e316f56922d2a98d424308df9e67699627e896e..0fdbfcef0541ae0a1745d75a2ec3d5c62a7b1433 100644 --- a/lib/dnssec/nsec3.h +++ b/lib/dnssec/nsec3.h @@ -39,6 +39,7 @@ int kr_nsec3_name_error_response_check(const knot_pkt_t *pkt, knot_section_t sec * KNOT_ERANGE - NSEC3 RR that covers a wildcard * has been found, but has opt-out flag set; * otherwise - error. + * Records over KR_NSEC3_MAX_ITERATIONS are skipped, so you probably get kr_error(ENOENT). */ int kr_nsec3_wildcard_answer_response_check(const knot_pkt_t *pkt, knot_section_t section_id, const knot_dname_t *sname, int trim_to_next); diff --git a/lib/layer/validate.c b/lib/layer/validate.c index cf5dda2de79946a491363bc85f19fa7f1221bebc..cf5c88a1e27264baebd208aa61de6d4b78cd2694 100644 --- a/lib/layer/validate.c +++ b/lib/layer/validate.c @@ -894,7 +894,8 @@ static void rank_records(struct kr_query *qry, bool any_rank, enum kr_rank rank_ bailiwick) < 0) { continue; } - if (kr_rank_test(entry->rank, KR_RANK_INITIAL) + if (any_rank + || kr_rank_test(entry->rank, KR_RANK_INITIAL) || kr_rank_test(entry->rank, KR_RANK_TRY) || kr_rank_test(entry->rank, KR_RANK_MISSING)) { kr_rank_set(&entry->rank, rank_to_set); diff --git a/tests/integration/deckard b/tests/integration/deckard index 01eabd23dc3315ef9d27ae7f5fe19c142dcbdfdb..c4628156e6cf499e8052c321b24793a176ded494 160000 --- a/tests/integration/deckard +++ b/tests/integration/deckard @@ -1 +1 @@ -Subproject commit 01eabd23dc3315ef9d27ae7f5fe19c142dcbdfdb +Subproject commit c4628156e6cf499e8052c321b24793a176ded494