From d389e0191bd1f89b5bb131d7bc3da0996f8d0e4b Mon Sep 17 00:00:00 2001 From: Simon Kelley Date: Mon, 27 Jul 2015 18:56:43 +0100 Subject: [PATCH] DNSSEC fix: correct logic for signed records in unsigned DNS space. --- src/dnssec.c | 12 ++++++---- src/forward.c | 62 +++++++++++++++++++++++++++++++++++++++++++-------- 2 files changed, 61 insertions(+), 13 deletions(-) diff --git a/src/dnssec.c b/src/dnssec.c index 39b6b51..55cf90b 100644 --- a/src/dnssec.c +++ b/src/dnssec.c @@ -1226,16 +1226,20 @@ int dnssec_validate_ds(time_t now, struct dns_header *header, size_t plen, char if (val == STAT_INSECURE) val = STAT_BOGUS; - if (val == STAT_NO_SIG) - return val; - p = (unsigned char *)(header+1); extract_name(header, plen, &p, name, 1, 4); p += 4; /* qtype, qclass */ if (!(p = skip_section(p, ntohs(header->ancount), header, plen))) val = STAT_BOGUS; - + + /* If we return STAT_NO_SIG, name contains the name of the DS query */ + if (val == STAT_NO_SIG) + { + *keyname = 0; + return val; + } + /* If the key needed to validate the DS is on the same domain as the DS, we'll loop getting nowhere. Stop that now. This can happen of the DS answer comes from the DS's zone, and not the parent zone. */ diff --git a/src/forward.c b/src/forward.c index de00ca0..2731b90 100644 --- a/src/forward.c +++ b/src/forward.c @@ -850,8 +850,19 @@ void reply_query(int fd, int family, time_t now) /* We only cache sigs when we've validated a reply. Avoid caching a reply with sigs if there's a vaildated break in the DS chain, so we don't return replies from cache missing sigs. */ - status = STAT_INSECURE_DS; - else if (status == STAT_NO_NS || status == STAT_NO_SIG) + status = STAT_INSECURE_DS; + else if (status == STAT_NO_SIG) + { + if (option_bool(OPT_DNSSEC_NO_SIGN)) + { + status = send_check_sign(forward, now, header, n, daemon->namebuff, daemon->keyname); + if (status == STAT_INSECURE) + status = STAT_INSECURE_DS; + } + else + status = STAT_INSECURE_DS; + } + else if (status == STAT_NO_NS) status = STAT_BOGUS; } else if (forward->flags & FREC_CHECK_NOSIGN) @@ -997,8 +1008,19 @@ void reply_query(int fd, int family, time_t now) Avoid caching a reply with sigs if there's a vaildated break in the DS chain, so we don't return replies from cache missing sigs. */ status = STAT_INSECURE_DS; - else if (status == STAT_NO_NS || status == STAT_NO_SIG) - status = STAT_BOGUS; + else if (status == STAT_NO_SIG) + { + if (option_bool(OPT_DNSSEC_NO_SIGN)) + { + status = send_check_sign(forward, now, header, n, daemon->namebuff, daemon->keyname); + if (status == STAT_INSECURE) + status = STAT_INSECURE_DS; + } + else + status = STAT_INSECURE_DS; + } + else if (status == STAT_NO_NS) + status = STAT_BOGUS; } else if (forward->flags & FREC_CHECK_NOSIGN) { @@ -1418,7 +1440,7 @@ static int send_check_sign(struct frec *forward, time_t now, struct dns_header * static int do_check_sign(struct frec *forward, int status, time_t now, char *name, char *keyname) { /* get domain we're checking back from blockdata store, it's stored on the original query. */ - while (forward->dependent) + while (forward->dependent && !forward->orig_domain) forward = forward->dependent; blockdata_retrieve(forward->orig_domain, forward->name_len, name); @@ -1451,7 +1473,7 @@ static int do_check_sign(struct frec *forward, int status, time_t now, char *nam /* Have entered non-signed part of DNS tree. */ if (status == STAT_NO_DS) - return STAT_INSECURE; + return forward->dependent ? STAT_INSECURE_DS : STAT_INSECURE; if (status == STAT_BOGUS) return STAT_BOGUS; @@ -1657,7 +1679,18 @@ static int tcp_key_recurse(time_t now, int status, struct dns_header *header, si { if (new_status == STAT_NO_DS) new_status = STAT_INSECURE_DS; - else if (new_status == STAT_NO_NS || new_status == STAT_NO_SIG) + if (new_status == STAT_NO_SIG) + { + if (option_bool(OPT_DNSSEC_NO_SIGN)) + { + new_status = tcp_check_for_unsigned_zone(now, header, n, class, name, keyname, server, keycount); + if (new_status == STAT_INSECURE) + new_status = STAT_INSECURE_DS; + } + else + new_status = STAT_INSECURE_DS; + } + else if (new_status == STAT_NO_NS) new_status = STAT_BOGUS; } } @@ -1722,8 +1755,19 @@ static int tcp_key_recurse(time_t now, int status, struct dns_header *header, si { if (new_status == STAT_NO_DS) new_status = STAT_INSECURE_DS; - else if (new_status == STAT_NO_NS || new_status == STAT_NO_SIG) - new_status = STAT_BOGUS; /* Validated no DS */ + else if (new_status == STAT_NO_SIG) + { + if (option_bool(OPT_DNSSEC_NO_SIGN)) + { + new_status = tcp_check_for_unsigned_zone(now, header, n, class, name, keyname, server, keycount); + if (new_status == STAT_INSECURE) + new_status = STAT_INSECURE_DS; + } + else + new_status = STAT_INSECURE_DS; + } + else if (new_status == STAT_NO_NS) + new_status = STAT_BOGUS; } } else if (status == STAT_CHASE_CNAME) -- 2.47.3