diff options
Diffstat (limited to 'src/resolve')
-rw-r--r-- | src/resolve/RFCs | 10 | ||||
-rw-r--r-- | src/resolve/resolved-bus.c | 5 | ||||
-rw-r--r-- | src/resolve/resolved-dns-answer.c | 86 | ||||
-rw-r--r-- | src/resolve/resolved-dns-answer.h | 2 | ||||
-rw-r--r-- | src/resolve/resolved-dns-cache.c | 17 | ||||
-rw-r--r-- | src/resolve/resolved-dns-cache.h | 2 | ||||
-rw-r--r-- | src/resolve/resolved-dns-dnssec.c | 99 | ||||
-rw-r--r-- | src/resolve/resolved-dns-dnssec.h | 14 | ||||
-rw-r--r-- | src/resolve/resolved-dns-rr.h | 26 | ||||
-rw-r--r-- | src/resolve/resolved-dns-transaction.c | 125 | ||||
-rw-r--r-- | src/resolve/resolved-dns-transaction.h | 4 | ||||
-rw-r--r-- | src/resolve/resolved-dns-trust-anchor.c | 183 | ||||
-rw-r--r-- | src/resolve/resolved-dns-trust-anchor.h | 2 | ||||
-rw-r--r-- | src/resolve/resolved-mdns.c | 2 | ||||
-rw-r--r-- | src/resolve/test-dnssec.c | 14 |
15 files changed, 509 insertions, 82 deletions
diff --git a/src/resolve/RFCs b/src/resolve/RFCs index ccc7f0d640..33f4dd9cb6 100644 --- a/src/resolve/RFCs +++ b/src/resolve/RFCs @@ -9,7 +9,7 @@ Y https://tools.ietf.org/html/rfc1034 → DOMAIN NAMES - CONCEPTS AND FACILITIES Y https://tools.ietf.org/html/rfc1035 → DOMAIN NAMES - IMPLEMENTATION AND SPECIFICATION ? https://tools.ietf.org/html/rfc1101 → DNS Encoding of Network Names and Other Types Y https://tools.ietf.org/html/rfc1123 → Requirements for Internet Hosts -- Application and Support - https://tools.ietf.org/html/rfc1464 → Using the Domain Name System To Store Arbitrary String Attributes +~ https://tools.ietf.org/html/rfc1464 → Using the Domain Name System To Store Arbitrary String Attributes Y https://tools.ietf.org/html/rfc1536 → Common DNS Implementation Errors and Suggested Fixes Y https://tools.ietf.org/html/rfc1876 → A Means for Expressing Location Information in the Domain Name System Y https://tools.ietf.org/html/rfc2181 → Clarifications to the DNS Specification @@ -30,9 +30,9 @@ Y https://tools.ietf.org/html/rfc4509 → Use of SHA-256 in DNSSEC Delegation Si ~ https://tools.ietf.org/html/rfc4592 → The Role of Wildcards in the Domain Name System ~ https://tools.ietf.org/html/rfc4697 → Observed DNS Resolution Misbehavior Y https://tools.ietf.org/html/rfc4795 → Link-Local Multicast Name Resolution (LLMNR) -! https://tools.ietf.org/html/rfc5011 → Automated Updates of DNS Security (DNSSEC) Trust Anchors +Y https://tools.ietf.org/html/rfc5011 → Automated Updates of DNS Security (DNSSEC) Trust Anchors https://tools.ietf.org/html/rfc5155 → DNS Security (DNSSEC) Hashed Authenticated Denial of Existence - https://tools.ietf.org/html/rfc5452 → Measures for Making DNS More Resilient against Forged Answers +Y https://tools.ietf.org/html/rfc5452 → Measures for Making DNS More Resilient against Forged Answers Y https://tools.ietf.org/html/rfc5702 → Use of SHA-2 Algorithms with RSA in DNSKEY and RRSIG Resource Records for DNSSEC Y https://tools.ietf.org/html/rfc5890 → Internationalized Domain Names for Applications (IDNA): Definitions and Document Framework Y https://tools.ietf.org/html/rfc5891 → Internationalized Domain Names in Applications (IDNA): Protocol @@ -41,7 +41,7 @@ Y https://tools.ietf.org/html/rfc6303 → Locally Served DNS Zones https://tools.ietf.org/html/rfc6604 → xNAME RCODE and Status Bits Clarification Y https://tools.ietf.org/html/rfc6605 → Elliptic Curve Digital Signature Algorithm (DSA) for DNSSEC https://tools.ietf.org/html/rfc6672 → DNAME Redirection in the DNS - https://tools.ietf.org/html/rfc6731 → Improved Recursive DNS Server Selection for Multi-Interfaced Nodes +! https://tools.ietf.org/html/rfc6731 → Improved Recursive DNS Server Selection for Multi-Interfaced Nodes Y https://tools.ietf.org/html/rfc6761 → Special-Use Domain Names https://tools.ietf.org/html/rfc6762 → Multicast DNS https://tools.ietf.org/html/rfc6763 → DNS-Based Service Discovery @@ -51,7 +51,7 @@ Y https://tools.ietf.org/html/rfc6891 → Extension Mechanisms for DNS (EDNS(0)) Y https://tools.ietf.org/html/rfc6944 → Applicability Statement: DNS Security (DNSSEC) DNSKEY Algorithm Implementation Status Y https://tools.ietf.org/html/rfc6975 → Signaling Cryptographic Algorithm Understanding in DNS Security Extensions (DNSSEC) https://tools.ietf.org/html/rfc7129 → Authenticated Denial of Existence in the DNS -! https://tools.ietf.org/html/rfc7646 → Definition and Use of DNSSEC Negative Trust Anchors +Y https://tools.ietf.org/html/rfc7646 → Definition and Use of DNSSEC Negative Trust Anchors ~ https://tools.ietf.org/html/rfc7719 → DNS Terminology Also relevant: diff --git a/src/resolve/resolved-bus.c b/src/resolve/resolved-bus.c index 4d4c1ca014..db180a51a3 100644 --- a/src/resolve/resolved-bus.c +++ b/src/resolve/resolved-bus.c @@ -64,9 +64,12 @@ static int reply_query_state(DnsQuery *q) { return sd_bus_reply_method_errorf(q->request, BUS_ERROR_ABORTED, "Query aborted"); case DNS_TRANSACTION_DNSSEC_FAILED: - return sd_bus_reply_method_errorf(q->request, BUS_ERROR_ABORTED, "DNSSEC validation failed: %s", + return sd_bus_reply_method_errorf(q->request, BUS_ERROR_DNSSEC_FAILED, "DNSSEC validation failed: %s", dnssec_result_to_string(q->answer_dnssec_result)); + case DNS_TRANSACTION_NO_TRUST_ANCHOR: + return sd_bus_reply_method_errorf(q->request, BUS_ERROR_NO_TRUST_ANCHOR, "No suitable trust anchor known"); + case DNS_TRANSACTION_RCODE_FAILURE: { _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL; diff --git a/src/resolve/resolved-dns-answer.c b/src/resolve/resolved-dns-answer.c index 445999f545..b50558e280 100644 --- a/src/resolve/resolved-dns-answer.c +++ b/src/resolve/resolved-dns-answer.c @@ -524,6 +524,92 @@ int dns_answer_remove_by_key(DnsAnswer **a, const DnsResourceKey *key) { return 1; } +int dns_answer_remove_by_rr(DnsAnswer **a, DnsResourceRecord *rm) { + bool found = false, other = false; + DnsResourceRecord *rr; + unsigned i; + int r; + + assert(a); + assert(rm); + + /* Remove all entries matching the specified RR from *a */ + + DNS_ANSWER_FOREACH(rr, *a) { + r = dns_resource_record_equal(rr, rm); + if (r < 0) + return r; + if (r > 0) + found = true; + else + other = true; + + if (found && other) + break; + } + + if (!found) + return 0; + + if (!other) { + *a = dns_answer_unref(*a); /* Return NULL for the empty answer */ + return 1; + } + + if ((*a)->n_ref > 1) { + _cleanup_(dns_answer_unrefp) DnsAnswer *copy = NULL; + DnsAnswerFlags flags; + int ifindex; + + copy = dns_answer_new((*a)->n_rrs); + if (!copy) + return -ENOMEM; + + DNS_ANSWER_FOREACH_FULL(rr, ifindex, flags, *a) { + r = dns_resource_record_equal(rr, rm); + if (r < 0) + return r; + if (r > 0) + continue; + + r = dns_answer_add_raw(copy, rr, ifindex, flags); + if (r < 0) + return r; + } + + dns_answer_unref(*a); + *a = copy; + copy = NULL; + + return 1; + } + + /* Only a single reference, edit in-place */ + + i = 0; + for (;;) { + if (i >= (*a)->n_rrs) + break; + + r = dns_resource_record_equal((*a)->items[i].rr, rm); + if (r < 0) + return r; + if (r > 0) { + /* Kill this entry */ + + dns_resource_record_unref((*a)->items[i].rr); + memmove((*a)->items + i, (*a)->items + i + 1, sizeof(DnsAnswerItem) * ((*a)->n_rrs - i - 1)); + (*a)->n_rrs --; + continue; + + } else + /* Keep this entry */ + i++; + } + + return 1; +} + int dns_answer_copy_by_key(DnsAnswer **a, DnsAnswer *source, const DnsResourceKey *key, DnsAnswerFlags or_flags) { DnsResourceRecord *rr_source; int ifindex_source, r; diff --git a/src/resolve/resolved-dns-answer.h b/src/resolve/resolved-dns-answer.h index 28ded3b252..715e487d94 100644 --- a/src/resolve/resolved-dns-answer.h +++ b/src/resolve/resolved-dns-answer.h @@ -77,6 +77,8 @@ int dns_answer_reserve(DnsAnswer **a, unsigned n_free); int dns_answer_reserve_or_clone(DnsAnswer **a, unsigned n_free); int dns_answer_remove_by_key(DnsAnswer **a, const DnsResourceKey *key); +int dns_answer_remove_by_rr(DnsAnswer **a, DnsResourceRecord *rr); + int dns_answer_copy_by_key(DnsAnswer **a, DnsAnswer *source, const DnsResourceKey *key, DnsAnswerFlags or_flags); int dns_answer_move_by_key(DnsAnswer **to, DnsAnswer **from, const DnsResourceKey *key, DnsAnswerFlags or_flags); diff --git a/src/resolve/resolved-dns-cache.c b/src/resolve/resolved-dns-cache.c index 1c7dd56b3b..301f383809 100644 --- a/src/resolve/resolved-dns-cache.c +++ b/src/resolve/resolved-dns-cache.c @@ -273,13 +273,13 @@ static DnsCacheItem* dns_cache_get(DnsCache *c, DnsResourceRecord *rr) { return NULL; } -static usec_t calculate_until(DnsResourceRecord *rr, usec_t timestamp, bool use_soa_minimum) { +static usec_t calculate_until(DnsResourceRecord *rr, uint32_t nsec_ttl, usec_t timestamp, bool use_soa_minimum) { uint32_t ttl; usec_t u; assert(rr); - ttl = rr->ttl; + ttl = MIN(rr->ttl, nsec_ttl); if (rr->key->type == DNS_TYPE_SOA && use_soa_minimum) { /* If this is a SOA RR, and it is requested, clamp to * the SOA's minimum field. This is used when we do @@ -339,7 +339,7 @@ static void dns_cache_item_update_positive( dns_resource_key_unref(i->key); i->key = dns_resource_key_ref(rr->key); - i->until = calculate_until(rr, timestamp, false); + i->until = calculate_until(rr, (uint32_t) -1, timestamp, false); i->authenticated = authenticated; i->shared_owner = shared_owner; @@ -420,7 +420,7 @@ static int dns_cache_put_positive( i->type = DNS_CACHE_POSITIVE; i->key = dns_resource_key_ref(rr->key); i->rr = dns_resource_record_ref(rr); - i->until = calculate_until(rr, timestamp, false); + i->until = calculate_until(rr, (uint32_t) -1, timestamp, false); i->authenticated = authenticated; i->shared_owner = shared_owner; i->owner_family = owner_family; @@ -448,6 +448,7 @@ static int dns_cache_put_negative( DnsResourceKey *key, int rcode, bool authenticated, + uint32_t nsec_ttl, usec_t timestamp, DnsResourceRecord *soa, int owner_family, @@ -470,13 +471,13 @@ static int dns_cache_put_negative( if (dns_type_is_pseudo(key->type)) return 0; - if (soa->soa.minimum <= 0 || soa->ttl <= 0) { + if (nsec_ttl <= 0 || soa->soa.minimum <= 0 || soa->ttl <= 0) { if (log_get_max_level() >= LOG_DEBUG) { r = dns_resource_key_to_string(key, &key_str); if (r < 0) return r; - log_debug("Not caching negative entry with zero SOA TTL: %s", key_str); + log_debug("Not caching negative entry with zero SOA/NSEC/NSEC3 TTL: %s", key_str); } return 0; @@ -496,7 +497,7 @@ static int dns_cache_put_negative( return -ENOMEM; i->type = rcode == DNS_RCODE_SUCCESS ? DNS_CACHE_NODATA : DNS_CACHE_NXDOMAIN; - i->until = calculate_until(soa, timestamp, true); + i->until = calculate_until(soa, nsec_ttl, timestamp, true); i->authenticated = authenticated; i->owner_family = owner_family; i->owner_address = *owner_address; @@ -571,6 +572,7 @@ int dns_cache_put( int rcode, DnsAnswer *answer, bool authenticated, + uint32_t nsec_ttl, usec_t timestamp, int owner_family, const union in_addr_union *owner_address) { @@ -669,6 +671,7 @@ int dns_cache_put( key, rcode, authenticated, + nsec_ttl, timestamp, soa, owner_family, owner_address); diff --git a/src/resolve/resolved-dns-cache.h b/src/resolve/resolved-dns-cache.h index 9c85ca4c58..e61b285df4 100644 --- a/src/resolve/resolved-dns-cache.h +++ b/src/resolve/resolved-dns-cache.h @@ -41,7 +41,7 @@ typedef struct DnsCache { void dns_cache_flush(DnsCache *c); void dns_cache_prune(DnsCache *c); -int dns_cache_put(DnsCache *c, DnsResourceKey *key, int rcode, DnsAnswer *answer, bool authenticated, usec_t timestamp, int owner_family, const union in_addr_union *owner_address); +int dns_cache_put(DnsCache *c, DnsResourceKey *key, int rcode, DnsAnswer *answer, bool authenticated, uint32_t nsec_ttl, usec_t timestamp, int owner_family, const union in_addr_union *owner_address); int dns_cache_lookup(DnsCache *c, DnsResourceKey *key, int *rcode, DnsAnswer **answer, bool *authenticated); int dns_cache_check_conflicts(DnsCache *cache, DnsResourceRecord *rr, int owner_family, const union in_addr_union *owner_address); diff --git a/src/resolve/resolved-dns-dnssec.c b/src/resolve/resolved-dns-dnssec.c index 1182201b7d..32d4834aa1 100644 --- a/src/resolve/resolved-dns-dnssec.c +++ b/src/resolve/resolved-dns-dnssec.c @@ -38,11 +38,8 @@ * - wildcard zones compatibility (NSEC/NSEC3 wildcard check is missing) * - multi-label zone compatibility * - cname/dname compatibility - * - per-interface DNSSEC setting * - nxdomain on qname - * - retry on failed validation? - * - DNSSEC key revocation support? https://tools.ietf.org/html/rfc5011 - * - when doing negative caching, use NSEC/NSEC3 RR instead of SOA for TTL + * - per-interface DNSSEC setting * * */ @@ -79,9 +76,9 @@ static void initialize_libgcrypt(void) { gcry_control(GCRYCTL_INITIALIZATION_FINISHED, 0); } -uint16_t dnssec_keytag(DnsResourceRecord *dnskey) { +uint16_t dnssec_keytag(DnsResourceRecord *dnskey, bool mask_revoke) { const uint8_t *p; - uint32_t sum; + uint32_t sum, f; size_t i; /* The algorithm from RFC 4034, Appendix B. */ @@ -89,8 +86,12 @@ uint16_t dnssec_keytag(DnsResourceRecord *dnskey) { assert(dnskey); assert(dnskey->key->type == DNS_TYPE_DNSKEY); - sum = (uint32_t) dnskey->dnskey.flags + - ((((uint32_t) dnskey->dnskey.protocol) << 8) + (uint32_t) dnskey->dnskey.algorithm); + f = (uint32_t) dnskey->dnskey.flags; + + if (mask_revoke) + f &= ~DNSKEY_FLAG_REVOKE; + + sum = f + ((((uint32_t) dnskey->dnskey.protocol) << 8) + (uint32_t) dnskey->dnskey.algorithm); p = dnskey->dnskey.key; @@ -116,15 +117,15 @@ static int rr_compare(const void *a, const void *b) { assert(*y); assert((*y)->wire_format); - m = MIN((*x)->wire_format_size, (*y)->wire_format_size); + m = MIN(DNS_RESOURCE_RECORD_RDATA_SIZE(*x), DNS_RESOURCE_RECORD_RDATA_SIZE(*y)); - r = memcmp((*x)->wire_format, (*y)->wire_format, m); + r = memcmp(DNS_RESOURCE_RECORD_RDATA(*x), DNS_RESOURCE_RECORD_RDATA(*y), m); if (r != 0) return r; - if ((*x)->wire_format_size < (*y)->wire_format_size) + if (DNS_RESOURCE_RECORD_RDATA_SIZE(*x) < DNS_RESOURCE_RECORD_RDATA_SIZE(*y)) return -1; - else if ((*x)->wire_format_size > (*y)->wire_format_size) + else if (DNS_RESOURCE_RECORD_RDATA_SIZE(*x) > DNS_RESOURCE_RECORD_RDATA_SIZE(*y)) return 1; return 0; @@ -494,7 +495,7 @@ static int algorithm_to_gcrypt_md(uint8_t algorithm) { int dnssec_verify_rrset( DnsAnswer *a, - DnsResourceKey *key, + const DnsResourceKey *key, DnsResourceRecord *rrsig, DnsResourceRecord *dnskey, usec_t realtime, @@ -605,12 +606,11 @@ int dnssec_verify_rrset( md_add_uint16(md, rr->key->class); md_add_uint32(md, rrsig->rrsig.original_ttl); - assert(rr->wire_format_rdata_offset <= rr->wire_format_size); - l = rr->wire_format_size - rr->wire_format_rdata_offset; + l = DNS_RESOURCE_RECORD_RDATA_SIZE(rr); assert(l <= 0xFFFF); md_add_uint16(md, (uint16_t) l); - gcry_md_write(md, (uint8_t*) rr->wire_format + rr->wire_format_rdata_offset, l); + gcry_md_write(md, DNS_RESOURCE_RECORD_RDATA(rr), l); } hash = gcry_md_read(md, 0); @@ -654,7 +654,7 @@ finish: return r; } -int dnssec_rrsig_match_dnskey(DnsResourceRecord *rrsig, DnsResourceRecord *dnskey) { +int dnssec_rrsig_match_dnskey(DnsResourceRecord *rrsig, DnsResourceRecord *dnskey, bool revoked_ok) { assert(rrsig); assert(dnskey); @@ -671,12 +671,14 @@ int dnssec_rrsig_match_dnskey(DnsResourceRecord *rrsig, DnsResourceRecord *dnske return 0; if ((dnskey->dnskey.flags & DNSKEY_FLAG_ZONE_KEY) == 0) return 0; + if (!revoked_ok && (dnskey->dnskey.flags & DNSKEY_FLAG_REVOKE)) + return 0; if (dnskey->dnskey.protocol != 3) return 0; if (dnskey->dnskey.algorithm != rrsig->rrsig.algorithm) return 0; - if (dnssec_keytag(dnskey) != rrsig->rrsig.key_tag) + if (dnssec_keytag(dnskey, false) != rrsig->rrsig.key_tag) return 0; return dns_name_equal(DNS_RESOURCE_KEY_NAME(dnskey->key), rrsig->rrsig.signer); @@ -738,7 +740,7 @@ static int dnssec_fix_rrset_ttl(DnsAnswer *a, const DnsResourceKey *key, DnsReso int dnssec_verify_rrset_search( DnsAnswer *a, - DnsResourceKey *key, + const DnsResourceKey *key, DnsAnswer *validated_dnskeys, usec_t realtime, DnssecResult *result) { @@ -777,7 +779,7 @@ int dnssec_verify_rrset_search( continue; /* Is this a DNSKEY RR that matches they key of our RRSIG? */ - r = dnssec_rrsig_match_dnskey(rrsig, dnskey); + r = dnssec_rrsig_match_dnskey(rrsig, dnskey, false); if (r < 0) return r; if (r == 0) @@ -957,7 +959,7 @@ static int digest_to_gcrypt_md(uint8_t algorithm) { } } -int dnssec_verify_dnskey(DnsResourceRecord *dnskey, DnsResourceRecord *ds) { +int dnssec_verify_dnskey(DnsResourceRecord *dnskey, DnsResourceRecord *ds, bool mask_revoke) { char owner_name[DNSSEC_CANONICAL_HOSTNAME_MAX]; gcry_md_hd_t md = NULL; size_t hash_size; @@ -975,12 +977,14 @@ int dnssec_verify_dnskey(DnsResourceRecord *dnskey, DnsResourceRecord *ds) { return -EINVAL; if ((dnskey->dnskey.flags & DNSKEY_FLAG_ZONE_KEY) == 0) return -EKEYREJECTED; + if (!mask_revoke && (dnskey->dnskey.flags & DNSKEY_FLAG_REVOKE)) + return -EKEYREJECTED; if (dnskey->dnskey.protocol != 3) return -EKEYREJECTED; if (dnskey->dnskey.algorithm != ds->ds.algorithm) return 0; - if (dnssec_keytag(dnskey) != ds->ds.key_tag) + if (dnssec_keytag(dnskey, mask_revoke) != ds->ds.key_tag) return 0; initialize_libgcrypt(); @@ -1004,7 +1008,10 @@ int dnssec_verify_dnskey(DnsResourceRecord *dnskey, DnsResourceRecord *ds) { return -EIO; gcry_md_write(md, owner_name, r); - md_add_uint16(md, dnskey->dnskey.flags); + if (mask_revoke) + md_add_uint16(md, dnskey->dnskey.flags & ~DNSKEY_FLAG_REVOKE); + else + md_add_uint16(md, dnskey->dnskey.flags); md_add_uint8(md, dnskey->dnskey.protocol); md_add_uint8(md, dnskey->dnskey.algorithm); gcry_md_write(md, dnskey->dnskey.key, dnskey->dnskey.key_size); @@ -1049,7 +1056,9 @@ int dnssec_verify_dnskey_search(DnsResourceRecord *dnskey, DnsAnswer *validated_ if (r == 0) continue; - r = dnssec_verify_dnskey(dnskey, ds); + r = dnssec_verify_dnskey(dnskey, ds, false); + if (r == -EKEYREJECTED) + return 0; /* The DNSKEY is revoked or otherwise invalid, we won't bless it */ if (r < 0) return r; if (r > 0) @@ -1073,7 +1082,7 @@ static int nsec3_hash_to_gcrypt_md(uint8_t algorithm) { } } -int dnssec_nsec3_hash(const DnsResourceRecord *nsec3, const char *name, void *ret) { +int dnssec_nsec3_hash(DnsResourceRecord *nsec3, const char *name, void *ret) { uint8_t wire_format[DNS_WIRE_FOMAT_HOSTNAME_MAX]; gcry_md_hd_t md = NULL; size_t hash_size; @@ -1089,8 +1098,10 @@ int dnssec_nsec3_hash(const DnsResourceRecord *nsec3, const char *name, void *re if (nsec3->key->type != DNS_TYPE_NSEC3) return -EINVAL; - if (nsec3->nsec3.iterations > NSEC3_ITERATIONS_MAX) + if (nsec3->nsec3.iterations > NSEC3_ITERATIONS_MAX) { + log_debug("Ignoring NSEC3 RR %s with excessive number of iterations.", dns_resource_record_to_string(nsec3)); return -EOPNOTSUPP; + } algorithm = nsec3_hash_to_gcrypt_md(nsec3->nsec3.algorithm); if (algorithm < 0) @@ -1200,7 +1211,7 @@ static int nsec3_is_good(DnsResourceRecord *rr, DnsAnswerFlags flags, DnsResourc return dns_name_equal(a, b); } -static int nsec3_hashed_domain(const DnsResourceRecord *nsec3, const char *domain, const char *zone, char **ret) { +static int nsec3_hashed_domain(DnsResourceRecord *nsec3, const char *domain, const char *zone, char **ret) { _cleanup_free_ char *l = NULL, *hashed_domain = NULL; uint8_t hashed[DNSSEC_HASH_SIZE_MAX]; int hashed_size; @@ -1238,7 +1249,7 @@ static int nsec3_hashed_domain(const DnsResourceRecord *nsec3, const char *domai * that there is no proof either way. The latter is the case if a the proof of non-existence of a given * name uses an NSEC3 record with the opt-out bit set. Lastly, if we are given insufficient NSEC3 records * to conclude anything we indicate this by returning NO_RR. */ -static int dnssec_test_nsec3(DnsAnswer *answer, DnsResourceKey *key, DnssecNsecResult *result, bool *authenticated) { +static int dnssec_test_nsec3(DnsAnswer *answer, DnsResourceKey *key, DnssecNsecResult *result, bool *authenticated, uint32_t *ttl) { _cleanup_free_ char *next_closer_domain = NULL, *wildcard = NULL, *wildcard_domain = NULL; const char *zone, *p, *pp = NULL; DnsResourceRecord *rr, *enclosure_rr, *suffix_rr, *wildcard_rr = NULL; @@ -1248,7 +1259,6 @@ static int dnssec_test_nsec3(DnsAnswer *answer, DnsResourceKey *key, DnssecNsecR assert(key); assert(result); - assert(authenticated); /* First step, find the zone name and the NSEC3 parameters of the zone. * it is sufficient to look for the longest common suffix we find with @@ -1357,7 +1367,10 @@ found_closest_encloser: else *result = DNSSEC_NSEC_NODATA; - *authenticated = a; + if (authenticated) + *authenticated = a; + if (ttl) + *ttl = enclosure_rr->ttl; return 0; } @@ -1440,7 +1453,6 @@ found_closest_encloser: if (!no_closer) { *result = DNSSEC_NSEC_NO_RR; - return 0; } @@ -1476,12 +1488,16 @@ found_closest_encloser: } } - *authenticated = a; + if (authenticated) + *authenticated = a; + + if (ttl) + *ttl = enclosure_rr->ttl; return 0; } -int dnssec_test_nsec(DnsAnswer *answer, DnsResourceKey *key, DnssecNsecResult *result, bool *authenticated) { +int dnssec_test_nsec(DnsAnswer *answer, DnsResourceKey *key, DnssecNsecResult *result, bool *authenticated, uint32_t *ttl) { DnsResourceRecord *rr; bool have_nsec3 = false; DnsAnswerFlags flags; @@ -1489,7 +1505,6 @@ int dnssec_test_nsec(DnsAnswer *answer, DnsResourceKey *key, DnssecNsecResult *r assert(key); assert(result); - assert(authenticated); /* Look for any NSEC/NSEC3 RRs that say something about the specified key. */ @@ -1512,7 +1527,12 @@ int dnssec_test_nsec(DnsAnswer *answer, DnsResourceKey *key, DnssecNsecResult *r *result = DNSSEC_NSEC_CNAME; else *result = DNSSEC_NSEC_NODATA; - *authenticated = flags & DNS_ANSWER_AUTHENTICATED; + + if (authenticated) + *authenticated = flags & DNS_ANSWER_AUTHENTICATED; + if (ttl) + *ttl = rr->ttl; + return 0; } @@ -1521,7 +1541,12 @@ int dnssec_test_nsec(DnsAnswer *answer, DnsResourceKey *key, DnssecNsecResult *r return r; if (r > 0) { *result = DNSSEC_NSEC_NXDOMAIN; - *authenticated = flags & DNS_ANSWER_AUTHENTICATED; + + if (authenticated) + *authenticated = flags & DNS_ANSWER_AUTHENTICATED; + if (ttl) + *ttl = rr->ttl; + return 0; } break; @@ -1534,7 +1559,7 @@ int dnssec_test_nsec(DnsAnswer *answer, DnsResourceKey *key, DnssecNsecResult *r /* OK, this was not sufficient. Let's see if NSEC3 can help. */ if (have_nsec3) - return dnssec_test_nsec3(answer, key, result, authenticated); + return dnssec_test_nsec3(answer, key, result, authenticated, ttl); /* No approproate NSEC RR found, report this. */ *result = DNSSEC_NSEC_NO_RR; diff --git a/src/resolve/resolved-dns-dnssec.h b/src/resolve/resolved-dns-dnssec.h index f106875027..94d0b23f80 100644 --- a/src/resolve/resolved-dns-dnssec.h +++ b/src/resolve/resolved-dns-dnssec.h @@ -72,22 +72,22 @@ enum DnssecResult { /* The longest digest we'll ever generate, of all digest algorithms we support */ #define DNSSEC_HASH_SIZE_MAX (MAX(20, 32)) -int dnssec_rrsig_match_dnskey(DnsResourceRecord *rrsig, DnsResourceRecord *dnskey); +int dnssec_rrsig_match_dnskey(DnsResourceRecord *rrsig, DnsResourceRecord *dnskey, bool revoked_ok); int dnssec_key_match_rrsig(const DnsResourceKey *key, DnsResourceRecord *rrsig); -int dnssec_verify_rrset(DnsAnswer *answer, DnsResourceKey *key, DnsResourceRecord *rrsig, DnsResourceRecord *dnskey, usec_t realtime, DnssecResult *result); -int dnssec_verify_rrset_search(DnsAnswer *answer, DnsResourceKey *key, DnsAnswer *validated_dnskeys, usec_t realtime, DnssecResult *result); +int dnssec_verify_rrset(DnsAnswer *answer, const DnsResourceKey *key, DnsResourceRecord *rrsig, DnsResourceRecord *dnskey, usec_t realtime, DnssecResult *result); +int dnssec_verify_rrset_search(DnsAnswer *answer, const DnsResourceKey *key, DnsAnswer *validated_dnskeys, usec_t realtime, DnssecResult *result); -int dnssec_verify_dnskey(DnsResourceRecord *dnskey, DnsResourceRecord *ds); +int dnssec_verify_dnskey(DnsResourceRecord *dnskey, DnsResourceRecord *ds, bool mask_revoke); int dnssec_verify_dnskey_search(DnsResourceRecord *dnskey, DnsAnswer *validated_ds); int dnssec_has_rrsig(DnsAnswer *a, const DnsResourceKey *key); -uint16_t dnssec_keytag(DnsResourceRecord *dnskey); +uint16_t dnssec_keytag(DnsResourceRecord *dnskey, bool mask_revoke); int dnssec_canonicalize(const char *n, char *buffer, size_t buffer_max); -int dnssec_nsec3_hash(const DnsResourceRecord *nsec3, const char *name, void *ret); +int dnssec_nsec3_hash(DnsResourceRecord *nsec3, const char *name, void *ret); typedef enum DnssecNsecResult { DNSSEC_NSEC_NO_RR, /* No suitable NSEC/NSEC3 RR found */ @@ -99,7 +99,7 @@ typedef enum DnssecNsecResult { DNSSEC_NSEC_OPTOUT, } DnssecNsecResult; -int dnssec_test_nsec(DnsAnswer *answer, DnsResourceKey *key, DnssecNsecResult *result, bool *authenticated); +int dnssec_test_nsec(DnsAnswer *answer, DnsResourceKey *key, DnssecNsecResult *result, bool *authenticated, uint32_t *ttl); const char* dnssec_mode_to_string(DnssecMode m) _const_; DnssecMode dnssec_mode_from_string(const char *s) _pure_; diff --git a/src/resolve/resolved-dns-rr.h b/src/resolve/resolved-dns-rr.h index 90c3629166..26ab36401c 100644 --- a/src/resolve/resolved-dns-rr.h +++ b/src/resolve/resolved-dns-rr.h @@ -34,8 +34,9 @@ typedef struct DnsResourceRecord DnsResourceRecord; typedef struct DnsTxtItem DnsTxtItem; /* DNSKEY RR flags */ -#define DNSKEY_FLAG_ZONE_KEY (UINT16_C(1) << 8) #define DNSKEY_FLAG_SEP (UINT16_C(1) << 0) +#define DNSKEY_FLAG_REVOKE (UINT16_C(1) << 7) +#define DNSKEY_FLAG_ZONE_KEY (UINT16_C(1) << 8) /* mDNS RR flags */ #define MDNS_RR_CACHE_FLUSH (UINT16_C(1) << 15) @@ -235,7 +236,7 @@ struct DnsResourceRecord { }; static inline const char* DNS_RESOURCE_KEY_NAME(const DnsResourceKey *key) { - if (_unlikely_(!key)) + if (!key) return NULL; if (key->_name) @@ -244,6 +245,27 @@ static inline const char* DNS_RESOURCE_KEY_NAME(const DnsResourceKey *key) { return (char*) key + sizeof(DnsResourceKey); } +static inline const void* DNS_RESOURCE_RECORD_RDATA(DnsResourceRecord *rr) { + if (!rr) + return NULL; + + if (!rr->wire_format) + return NULL; + + assert(rr->wire_format_rdata_offset <= rr->wire_format_size); + return (uint8_t*) rr->wire_format + rr->wire_format_rdata_offset; +} + +static inline size_t DNS_RESOURCE_RECORD_RDATA_SIZE(DnsResourceRecord *rr) { + if (!rr) + return 0; + if (!rr->wire_format) + return 0; + + assert(rr->wire_format_rdata_offset <= rr->wire_format_size); + return rr->wire_format_size - rr->wire_format_rdata_offset; +} + DnsResourceKey* dns_resource_key_new(uint16_t class, uint16_t type, const char *name); DnsResourceKey* dns_resource_key_new_redirect(const DnsResourceKey *key, const DnsResourceRecord *cname); int dns_resource_key_new_append_suffix(DnsResourceKey **ret, DnsResourceKey *key, char *name); diff --git a/src/resolve/resolved-dns-transaction.c b/src/resolve/resolved-dns-transaction.c index f7671e070f..870b7586fd 100644 --- a/src/resolve/resolved-dns-transaction.c +++ b/src/resolve/resolved-dns-transaction.c @@ -19,6 +19,8 @@ along with systemd; If not, see <http://www.gnu.org/licenses/>. ***/ +#include <sd-messages.h> + #include "af-list.h" #include "alloc-util.h" #include "dns-domain.h" @@ -38,6 +40,7 @@ static void dns_transaction_reset_answer(DnsTransaction *t) { t->answer_dnssec_result = _DNSSEC_RESULT_INVALID; t->answer_source = _DNS_TRANSACTION_SOURCE_INVALID; t->answer_authenticated = false; + t->answer_nsec_ttl = (uint32_t) -1; } static void dns_transaction_close_connection(DnsTransaction *t) { @@ -62,6 +65,8 @@ DnsTransaction* dns_transaction_free(DnsTransaction *t) { if (!t) return NULL; + log_debug("Freeing transaction %" PRIu16 ".", t->id); + dns_transaction_close_connection(t); dns_transaction_stop_timeout(t); @@ -106,16 +111,20 @@ DnsTransaction* dns_transaction_free(DnsTransaction *t) { DEFINE_TRIVIAL_CLEANUP_FUNC(DnsTransaction*, dns_transaction_free); -void dns_transaction_gc(DnsTransaction *t) { +bool dns_transaction_gc(DnsTransaction *t) { assert(t); if (t->block_gc > 0) - return; + return true; if (set_isempty(t->notify_query_candidates) && set_isempty(t->notify_zone_items) && - set_isempty(t->notify_transactions)) + set_isempty(t->notify_transactions)) { dns_transaction_free(t); + return false; + } + + return true; } int dns_transaction_new(DnsTransaction **ret, DnsScope *s, DnsResourceKey *key) { @@ -149,6 +158,7 @@ int dns_transaction_new(DnsTransaction **ret, DnsScope *s, DnsResourceKey *key) t->dns_udp_fd = -1; t->answer_source = _DNS_TRANSACTION_SOURCE_INVALID; t->answer_dnssec_result = _DNSSEC_RESULT_INVALID; + t->answer_nsec_ttl = (uint32_t) -1; t->key = dns_resource_key_ref(key); /* Find a fresh, unused transaction id */ @@ -237,6 +247,7 @@ void dns_transaction_complete(DnsTransaction *t, DnsTransactionState state) { if (state == DNS_TRANSACTION_DNSSEC_FAILED) log_struct(LOG_NOTICE, + LOG_MESSAGE_ID(SD_MESSAGE_DNSSEC_FAILURE), LOG_MESSAGE("DNSSEC validation failed for question %s: %s", dns_transaction_key_string(t), dnssec_result_to_string(t->answer_dnssec_result)), "DNS_TRANSACTION=%" PRIu16, t->id, "DNS_QUESTION=%s", dns_transaction_key_string(t), @@ -473,6 +484,7 @@ static void dns_transaction_cache_answer(DnsTransaction *t) { t->answer_rcode, t->answer, t->answer_authenticated, + t->answer_nsec_ttl, 0, t->received->family, &t->received->sender); @@ -718,7 +730,22 @@ void dns_transaction_process_reply(DnsTransaction *t, DnsPacket *p) { t->answer_dnssec_result = _DNSSEC_RESULT_INVALID; t->answer_authenticated = false; + /* Block GC while starting requests for additional DNSSEC RRs */ + t->block_gc++; r = dns_transaction_request_dnssec_keys(t); + t->block_gc--; + + /* Maybe the transaction is ready for GC'ing now? If so, free it and return. */ + if (!dns_transaction_gc(t)) + return; + + /* Requesting additional keys might have resulted in + * this transaction to fail, since the auxiliary + * request failed for some reason. If so, we are not + * in pending state anymore, and we should exit + * quickly. */ + if (t->state != DNS_TRANSACTION_PENDING) + return; if (r < 0) { dns_transaction_complete(t, DNS_TRANSACTION_RESOURCES); return; @@ -902,6 +929,41 @@ static int dns_transaction_prepare(DnsTransaction *t, usec_t ts) { dns_transaction_complete(t, DNS_TRANSACTION_SUCCESS); return 0; } + + if (dns_name_is_root(DNS_RESOURCE_KEY_NAME(t->key)) && + t->key->type == DNS_TYPE_DS) { + + /* Hmm, this is a request for the root DS? A + * DS RR doesn't exist in the root zone, and + * if our trust anchor didn't know it either, + * this means we cannot do any DNSSEC logic + * anymore. */ + + if (t->scope->dnssec_mode == DNSSEC_DOWNGRADE_OK) { + /* We are in downgrade mode. In this + * case, synthesize an unsigned empty + * response, so that the any lookup + * depending on this one can continue + * assuming there was no DS, and hence + * the root zone was unsigned. */ + + t->answer_rcode = DNS_RCODE_SUCCESS; + t->answer_source = DNS_TRANSACTION_TRUST_ANCHOR; + t->answer_authenticated = false; + dns_transaction_complete(t, DNS_TRANSACTION_SUCCESS); + } else + /* If we are not in downgrade mode, + * then fail the lookup, because we + * cannot reasonably answer it. There + * might be DS RRs, but we don't know + * them, and the DNS server won't tell + * them to us (and even if it would, + * we couldn't validate it and trust + * it). */ + dns_transaction_complete(t, DNS_TRANSACTION_NO_TRUST_ANCHOR); + + return 0; + } } /* Check the zone, but only if this transaction is not used @@ -1209,6 +1271,28 @@ int dns_transaction_go(DnsTransaction *t) { return 1; } +static int dns_transaction_find_cyclic(DnsTransaction *t, DnsTransaction *aux) { + DnsTransaction *n; + Iterator i; + int r; + + assert(t); + assert(aux); + + /* Try to find cyclic dependencies between transaction objects */ + + if (t == aux) + return 1; + + SET_FOREACH(n, aux->notify_transactions, i) { + r = dns_transaction_find_cyclic(t, n); + if (r != 0) + return r; + } + + return r; +} + static int dns_transaction_add_dnssec_transaction(DnsTransaction *t, DnsResourceKey *key, DnsTransaction **ret) { DnsTransaction *aux; int r; @@ -1227,6 +1311,18 @@ static int dns_transaction_add_dnssec_transaction(DnsTransaction *t, DnsResource *ret = aux; return 0; } + + r = dns_transaction_find_cyclic(t, aux); + if (r < 0) + return r; + if (r > 0) { + log_debug("Detected potential cyclic dependency, refusing to add transaction %" PRIu16 " (%s) as dependency for %" PRIu16 " (%s).", + aux->id, + strna(dns_transaction_key_string(aux)), + t->id, + strna(dns_transaction_key_string(t))); + return -ELOOP; + } } r = set_ensure_allocated(&t->dnssec_transactions, NULL); @@ -1263,12 +1359,6 @@ static int dns_transaction_request_dnssec_rr(DnsTransaction *t, DnsResourceKey * assert(t); assert(key); - r = dns_resource_key_equal(t->key, key); - if (r < 0) - return r; - if (r > 0) /* Don't go in circles */ - return 0; - /* Try to get the data from the trust anchor */ r = dns_trust_anchor_lookup_positive(&t->scope->manager->trust_anchor, key, &a); if (r < 0) @@ -1283,6 +1373,8 @@ static int dns_transaction_request_dnssec_rr(DnsTransaction *t, DnsResourceKey * /* This didn't work, ask for it via the network/cache then. */ r = dns_transaction_add_dnssec_transaction(t, key, &aux); + if (r == -ELOOP) /* This would result in a cyclic dependency */ + return 0; if (r < 0) return r; @@ -1292,7 +1384,7 @@ static int dns_transaction_request_dnssec_rr(DnsTransaction *t, DnsResourceKey * return r; } - return 0; + return 1; } static int dns_transaction_has_positive_answer(DnsTransaction *t, DnsAnswerFlags *flags) { @@ -1494,7 +1586,7 @@ int dns_transaction_request_dnssec_keys(DnsTransaction *t) { if (!ds) return -ENOMEM; - log_debug("Requesting DS to validate transaction %" PRIu16" (%s, DNSKEY with key tag: %" PRIu16 ").", t->id, DNS_RESOURCE_KEY_NAME(rr->key), dnssec_keytag(rr)); + log_debug("Requesting DS to validate transaction %" PRIu16" (%s, DNSKEY with key tag: %" PRIu16 ").", t->id, DNS_RESOURCE_KEY_NAME(rr->key), dnssec_keytag(rr, false)); r = dns_transaction_request_dnssec_rr(t, ds); if (r < 0) return r; @@ -2116,6 +2208,14 @@ int dns_transaction_validate_dnssec(DnsTransaction *t) { r = dns_answer_copy_by_key(&t->validated_keys, t->answer, rr->key, DNS_ANSWER_AUTHENTICATED); if (r < 0) return r; + + /* Maybe warn the user that we + * encountered a revoked + * DNSKEY for a key from our + * trust anchor */ + r = dns_trust_anchor_check_revoked(&t->scope->manager->trust_anchor, t->answer, rr->key); + if (r < 0) + return r; } /* Add the validated RRset to the new @@ -2288,7 +2388,7 @@ int dns_transaction_validate_dnssec(DnsTransaction *t) { bool authenticated = false; /* Bummer! Let's check NSEC/NSEC3 */ - r = dnssec_test_nsec(t->answer, t->key, &nr, &authenticated); + r = dnssec_test_nsec(t->answer, t->key, &nr, &authenticated, &t->answer_nsec_ttl); if (r < 0) return r; @@ -2376,6 +2476,7 @@ static const char* const dns_transaction_state_table[_DNS_TRANSACTION_STATE_MAX] [DNS_TRANSACTION_CONNECTION_FAILURE] = "connection-failure", [DNS_TRANSACTION_ABORTED] = "aborted", [DNS_TRANSACTION_DNSSEC_FAILED] = "dnssec-failed", + [DNS_TRANSACTION_NO_TRUST_ANCHOR] = "no-trust-anchor", }; DEFINE_STRING_TABLE_LOOKUP(dns_transaction_state, DnsTransactionState); diff --git a/src/resolve/resolved-dns-transaction.h b/src/resolve/resolved-dns-transaction.h index faf3ce6fb9..ede33f9547 100644 --- a/src/resolve/resolved-dns-transaction.h +++ b/src/resolve/resolved-dns-transaction.h @@ -39,6 +39,7 @@ enum DnsTransactionState { DNS_TRANSACTION_CONNECTION_FAILURE, DNS_TRANSACTION_ABORTED, DNS_TRANSACTION_DNSSEC_FAILED, + DNS_TRANSACTION_NO_TRUST_ANCHOR, _DNS_TRANSACTION_STATE_MAX, _DNS_TRANSACTION_STATE_INVALID = -1 }; @@ -80,6 +81,7 @@ struct DnsTransaction { int answer_rcode; DnssecResult answer_dnssec_result; DnsTransactionSource answer_source; + uint32_t answer_nsec_ttl; /* Indicates whether the primary answer is authenticated, * i.e. whether the RRs from answer which directly match the @@ -140,7 +142,7 @@ struct DnsTransaction { int dns_transaction_new(DnsTransaction **ret, DnsScope *s, DnsResourceKey *key); DnsTransaction* dns_transaction_free(DnsTransaction *t); -void dns_transaction_gc(DnsTransaction *t); +bool dns_transaction_gc(DnsTransaction *t); int dns_transaction_go(DnsTransaction *t); void dns_transaction_process_reply(DnsTransaction *t, DnsPacket *p); diff --git a/src/resolve/resolved-dns-trust-anchor.c b/src/resolve/resolved-dns-trust-anchor.c index 03c5b9406e..53b49b091a 100644 --- a/src/resolve/resolved-dns-trust-anchor.c +++ b/src/resolve/resolved-dns-trust-anchor.c @@ -19,6 +19,8 @@ along with systemd; If not, see <http://www.gnu.org/licenses/>. ***/ +#include <sd-messages.h> + #include "alloc-util.h" #include "conf-files.h" #include "def.h" @@ -28,11 +30,12 @@ #include "hexdecoct.h" #include "parse-util.h" #include "resolved-dns-trust-anchor.h" +#include "resolved-dns-dnssec.h" #include "set.h" #include "string-util.h" #include "strv.h" -static const char trust_anchor_dirs[] = CONF_PATHS_NULSTR("systemd/dnssec-trust-anchors.d"); +static const char trust_anchor_dirs[] = CONF_PATHS_NULSTR("dnssec-trust-anchors.d"); /* The DS RR from https://data.iana.org/root-anchors/root-anchors.xml, retrieved December 2015 */ static const uint8_t root_digest[] = @@ -53,6 +56,9 @@ static int dns_trust_anchor_add_builtin(DnsTrustAnchor *d) { if (hashmap_get(d->positive_by_key, &DNS_RESOURCE_KEY_CONST(DNS_CLASS_IN, DNS_TYPE_DS, "."))) return 0; + if (hashmap_get(d->positive_by_key, &DNS_RESOURCE_KEY_CONST(DNS_CLASS_IN, DNS_TYPE_DNSKEY, "."))) + return 0; + /* Add the RR from https://data.iana.org/root-anchors/root-anchors.xml */ rr = dns_resource_record_new_full(DNS_CLASS_IN, DNS_TYPE_DS, ""); if (!rr) @@ -188,6 +194,14 @@ static int dns_trust_anchor_load_positive(DnsTrustAnchor *d, const char *path, u r = safe_atou16(flags, &f); if (r < 0) return log_warning_errno(r, "Failed to parse DNSKEY flags field %s on line %s:%u", flags, path, line); + if ((f & DNSKEY_FLAG_ZONE_KEY) == 0) { + log_warning("DNSKEY lacks zone key bit set on line %s:%u", path, line); + return -EINVAL; + } + if ((f & DNSKEY_FLAG_REVOKE)) { + log_warning("DNSKEY is already revoked on line %s:%u", path, line); + return -EINVAL; + } a = dnssec_algorithm_from_string(algorithm); if (a < 0) { @@ -405,3 +419,170 @@ int dns_trust_anchor_lookup_negative(DnsTrustAnchor *d, const char *name) { return set_contains(d->negative_by_name, name); } + +static int dns_trust_anchor_remove_revoked(DnsTrustAnchor *d, DnsResourceRecord *rr) { + _cleanup_(dns_answer_unrefp) DnsAnswer *new_answer = NULL; + DnsAnswer *old_answer; + int r; + + old_answer = hashmap_get(d->positive_by_key, rr->key); + if (!old_answer) + return 0; + + new_answer = dns_answer_ref(old_answer); + + r = dns_answer_remove_by_rr(&new_answer, rr); + if (r <= 0) + return r; + + /* We found the key! Warn the user */ + log_struct(LOG_WARNING, + LOG_MESSAGE_ID(SD_MESSAGE_DNSSEC_TRUST_ANCHOR_REVOKED), + LOG_MESSAGE("DNSSEC Trust anchor %s has been revoked. Please update the trust anchor, or upgrade your operating system."), strna(dns_resource_record_to_string(rr)), + "TRUST_ANCHOR=%s", dns_resource_record_to_string(rr), + NULL); + + if (dns_answer_size(new_answer) <= 0) { + assert_se(hashmap_remove(d->positive_by_key, rr->key) == old_answer); + dns_answer_unref(old_answer); + return 1; + } + + r = hashmap_replace(d->positive_by_key, new_answer->items[0].rr->key, new_answer); + if (r < 0) + return r; + + new_answer = NULL; + dns_answer_unref(old_answer); + return 1; +} + +static int dns_trust_anchor_check_revoked_one(DnsTrustAnchor *d, DnsResourceRecord *revoked_dnskey) { + DnsAnswer *a; + int r; + + assert(d); + assert(revoked_dnskey); + assert(revoked_dnskey->key->type == DNS_TYPE_DNSKEY); + assert(revoked_dnskey->dnskey.flags & DNSKEY_FLAG_REVOKE); + + a = hashmap_get(d->positive_by_key, revoked_dnskey->key); + if (a) { + DnsResourceRecord *anchor; + + /* First, look for the precise DNSKEY in our trust anchor database */ + + DNS_ANSWER_FOREACH(anchor, a) { + + if (anchor->dnskey.protocol != revoked_dnskey->dnskey.protocol) + continue; + + if (anchor->dnskey.algorithm != revoked_dnskey->dnskey.algorithm) + continue; + + if (anchor->dnskey.key_size != revoked_dnskey->dnskey.key_size) + continue; + + if (((anchor->dnskey.flags ^ revoked_dnskey->dnskey.flags) | DNSKEY_FLAG_REVOKE) != DNSKEY_FLAG_REVOKE) + continue; + + if (memcmp(anchor->dnskey.key, revoked_dnskey->dnskey.key, anchor->dnskey.key_size) != 0) + continue; + + dns_trust_anchor_remove_revoked(d, anchor); + break; + } + } + + a = hashmap_get(d->positive_by_key, &DNS_RESOURCE_KEY_CONST(revoked_dnskey->key->class, DNS_TYPE_DS, DNS_RESOURCE_KEY_NAME(revoked_dnskey->key))); + if (a) { + DnsResourceRecord *anchor; + + /* Second, look for DS RRs matching this DNSKEY in our trust anchor database */ + + DNS_ANSWER_FOREACH(anchor, a) { + + r = dnssec_verify_dnskey(revoked_dnskey, anchor, true); + if (r < 0) + return r; + if (r == 0) + continue; + + dns_trust_anchor_remove_revoked(d, anchor); + break; + } + } + + return 0; +} + +static bool dns_trust_anchor_knows_domain(DnsTrustAnchor *d, const char *name) { + assert(d); + + /* Returns true if there's an entry for the specified domain + * name in our trust anchor */ + + return + hashmap_contains(d->positive_by_key, &DNS_RESOURCE_KEY_CONST(DNS_CLASS_IN, DNS_TYPE_DNSKEY, name)) || + hashmap_contains(d->positive_by_key, &DNS_RESOURCE_KEY_CONST(DNS_CLASS_IN, DNS_TYPE_DS, name)); +} + +int dns_trust_anchor_check_revoked(DnsTrustAnchor *d, DnsAnswer *rrs, const DnsResourceKey *key) { + DnsResourceRecord *dnskey; + int r; + + assert(d); + assert(key); + + /* Looks for self-signed DNSKEY RRs in "rrs" that have been revoked. */ + + if (key->type != DNS_TYPE_DNSKEY) + return 0; + + DNS_ANSWER_FOREACH(dnskey, rrs) { + DnsResourceRecord *rrsig; + DnssecResult result; + + r = dns_resource_key_equal(key, dnskey->key); + if (r < 0) + return r; + if (r == 0) + continue; + + /* Is this DNSKEY revoked? */ + if ((dnskey->dnskey.flags & DNSKEY_FLAG_REVOKE) == 0) + continue; + + /* Could this be interesting to us at all? If not, + * there's no point in looking for and verifying a + * self-signed RRSIG. */ + if (!dns_trust_anchor_knows_domain(d, DNS_RESOURCE_KEY_NAME(dnskey->key))) + continue; + + /* Look for a self-signed RRSIG */ + DNS_ANSWER_FOREACH(rrsig, rrs) { + + if (rrsig->key->type != DNS_TYPE_RRSIG) + continue; + + r = dnssec_rrsig_match_dnskey(rrsig, dnskey, true); + if (r < 0) + return r; + if (r == 0) + continue; + + r = dnssec_verify_rrset(rrs, key, rrsig, dnskey, USEC_INFINITY, &result); + if (r < 0) + return r; + if (result != DNSSEC_VALIDATED) + continue; + + /* Bingo! Now, act! */ + r = dns_trust_anchor_check_revoked_one(d, dnskey); + if (r < 0) + return r; + } + } + + return 0; +} diff --git a/src/resolve/resolved-dns-trust-anchor.h b/src/resolve/resolved-dns-trust-anchor.h index 1140cde041..303c4088d1 100644 --- a/src/resolve/resolved-dns-trust-anchor.h +++ b/src/resolve/resolved-dns-trust-anchor.h @@ -39,3 +39,5 @@ void dns_trust_anchor_flush(DnsTrustAnchor *d); int dns_trust_anchor_lookup_positive(DnsTrustAnchor *d, const DnsResourceKey* key, DnsAnswer **answer); int dns_trust_anchor_lookup_negative(DnsTrustAnchor *d, const char *name); + +int dns_trust_anchor_check_revoked(DnsTrustAnchor *d, DnsAnswer *rrs, const DnsResourceKey *key); diff --git a/src/resolve/resolved-mdns.c b/src/resolve/resolved-mdns.c index db23bc9d42..7c1012f4ea 100644 --- a/src/resolve/resolved-mdns.c +++ b/src/resolve/resolved-mdns.c @@ -122,7 +122,7 @@ static int on_mdns_packet(sd_event_source *s, int fd, uint32_t revents, void *us dns_transaction_process_reply(t, p); } - dns_cache_put(&scope->cache, NULL, DNS_PACKET_RCODE(p), p->answer, false, 0, p->family, &p->sender); + dns_cache_put(&scope->cache, NULL, DNS_PACKET_RCODE(p), p->answer, false, (uint32_t) -1, 0, p->family, &p->sender); } else if (dns_packet_validate_query(p) > 0) { log_debug("Got mDNS query packet for id %u", DNS_PACKET_ID(p)); diff --git a/src/resolve/test-dnssec.c b/src/resolve/test-dnssec.c index 6104d8b4c0..0c9efde1fe 100644 --- a/src/resolve/test-dnssec.c +++ b/src/resolve/test-dnssec.c @@ -107,10 +107,10 @@ static void test_dnssec_verify_rrset2(void) { assert_se(dnskey->dnskey.key); log_info("DNSKEY: %s", strna(dns_resource_record_to_string(dnskey))); - log_info("DNSKEY keytag: %u", dnssec_keytag(dnskey)); + log_info("DNSKEY keytag: %u", dnssec_keytag(dnskey, false)); assert_se(dnssec_key_match_rrsig(nsec->key, rrsig) > 0); - assert_se(dnssec_rrsig_match_dnskey(rrsig, dnskey) > 0); + assert_se(dnssec_rrsig_match_dnskey(rrsig, dnskey, false) > 0); answer = dns_answer_new(1); assert_se(answer); @@ -186,10 +186,10 @@ static void test_dnssec_verify_rrset(void) { assert_se(dnskey->dnskey.key); log_info("DNSKEY: %s", strna(dns_resource_record_to_string(dnskey))); - log_info("DNSKEY keytag: %u", dnssec_keytag(dnskey)); + log_info("DNSKEY keytag: %u", dnssec_keytag(dnskey, false)); assert_se(dnssec_key_match_rrsig(a->key, rrsig) > 0); - assert_se(dnssec_rrsig_match_dnskey(rrsig, dnskey) > 0); + assert_se(dnssec_rrsig_match_dnskey(rrsig, dnskey, false) > 0); answer = dns_answer_new(1); assert_se(answer); @@ -268,10 +268,10 @@ static void test_dnssec_verify_dns_key(void) { assert_se(dnskey->dnskey.key); log_info("DNSKEY: %s", strna(dns_resource_record_to_string(dnskey))); - log_info("DNSKEY keytag: %u", dnssec_keytag(dnskey)); + log_info("DNSKEY keytag: %u", dnssec_keytag(dnskey, false)); - assert_se(dnssec_verify_dnskey(dnskey, ds1) > 0); - assert_se(dnssec_verify_dnskey(dnskey, ds2) > 0); + assert_se(dnssec_verify_dnskey(dnskey, ds1, false) > 0); + assert_se(dnssec_verify_dnskey(dnskey, ds2, false) > 0); } static void test_dnssec_canonicalize_one(const char *original, const char *canonical, int r) { |