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Diffstat (limited to 'src/resolve/resolved-dns-dnssec.c')
-rw-r--r--src/resolve/resolved-dns-dnssec.c99
1 files changed, 62 insertions, 37 deletions
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;
generated by cgit v1.2.3-54-g00ecf (git 2.45.2) at 2024-09-14 23:09:01 +0000