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Diffstat (limited to 'src/resolve/resolved-dns-dnssec.c')
-rw-r--r--src/resolve/resolved-dns-dnssec.c940
1 files changed, 754 insertions, 186 deletions
diff --git a/src/resolve/resolved-dns-dnssec.c b/src/resolve/resolved-dns-dnssec.c
index 1182201b7d..1f48f588ce 100644
--- a/src/resolve/resolved-dns-dnssec.c
+++ b/src/resolve/resolved-dns-dnssec.c
@@ -35,15 +35,12 @@
*
* TODO:
*
- * - 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
- *
+ * - bus calls to override DNSEC setting per interface
+ * - log all DNSSEC downgrades
+ * - log all RRs that failed validation
+ * - enable by default
+ * - Allow clients to request DNSSEC even if DNSSEC is off
+ * - make sure when getting an NXDOMAIN response through CNAME, we still process the first CNAMEs in the packet
* */
#define VERIFY_RRS_MAX 256
@@ -52,8 +49,8 @@
/* Permit a maximum clock skew of 1h 10min. This should be enough to deal with DST confusion */
#define SKEW_MAX (1*USEC_PER_HOUR + 10*USEC_PER_MINUTE)
-/* Maximum number of NSEC3 iterations we'll do. */
-#define NSEC3_ITERATIONS_MAX 2048
+/* Maximum number of NSEC3 iterations we'll do. RFC5155 says 2500 shall be the maximum useful value */
+#define NSEC3_ITERATIONS_MAX 2500
/*
* The DNSSEC Chain of trust:
@@ -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;
@@ -424,6 +425,57 @@ static void md_add_uint32(gcry_md_hd_t md, uint32_t v) {
gcry_md_write(md, &v, sizeof(v));
}
+static int dnssec_rrsig_prepare(DnsResourceRecord *rrsig) {
+ int n_key_labels, n_signer_labels;
+ const char *name;
+ int r;
+
+ /* Checks whether the specified RRSIG RR is somewhat valid, and initializes the .n_skip_labels_source and
+ * .n_skip_labels_signer fields so that we can use them later on. */
+
+ assert(rrsig);
+ assert(rrsig->key->type == DNS_TYPE_RRSIG);
+
+ /* Check if this RRSIG RR is already prepared */
+ if (rrsig->n_skip_labels_source != (unsigned) -1)
+ return 0;
+
+ if (rrsig->rrsig.inception > rrsig->rrsig.expiration)
+ return -EINVAL;
+
+ name = DNS_RESOURCE_KEY_NAME(rrsig->key);
+
+ n_key_labels = dns_name_count_labels(name);
+ if (n_key_labels < 0)
+ return n_key_labels;
+ if (rrsig->rrsig.labels > n_key_labels)
+ return -EINVAL;
+
+ n_signer_labels = dns_name_count_labels(rrsig->rrsig.signer);
+ if (n_signer_labels < 0)
+ return n_signer_labels;
+ if (n_signer_labels > rrsig->rrsig.labels)
+ return -EINVAL;
+
+ r = dns_name_skip(name, n_key_labels - n_signer_labels, &name);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ return -EINVAL;
+
+ /* Check if the signer is really a suffix of us */
+ r = dns_name_equal(name, rrsig->rrsig.signer);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ return -EINVAL;
+
+ rrsig->n_skip_labels_source = n_key_labels - rrsig->rrsig.labels;
+ rrsig->n_skip_labels_signer = n_key_labels - n_signer_labels;
+
+ return 0;
+}
+
static int dnssec_rrsig_expired(DnsResourceRecord *rrsig, usec_t realtime) {
usec_t expiration, inception, skew;
@@ -436,8 +488,9 @@ static int dnssec_rrsig_expired(DnsResourceRecord *rrsig, usec_t realtime) {
expiration = rrsig->rrsig.expiration * USEC_PER_SEC;
inception = rrsig->rrsig.inception * USEC_PER_SEC;
+ /* Consider inverted validity intervals as expired */
if (inception > expiration)
- return -EKEYREJECTED;
+ return true;
/* Permit a certain amount of clock skew of 10% of the valid
* time range. This takes inspiration from unbound's
@@ -492,21 +545,52 @@ static int algorithm_to_gcrypt_md(uint8_t algorithm) {
}
}
+static void dnssec_fix_rrset_ttl(
+ DnsResourceRecord *list[],
+ unsigned n,
+ DnsResourceRecord *rrsig,
+ usec_t realtime) {
+
+ unsigned k;
+
+ assert(list);
+ assert(n > 0);
+ assert(rrsig);
+
+ for (k = 0; k < n; k++) {
+ DnsResourceRecord *rr = list[k];
+
+ /* Pick the TTL as the minimum of the RR's TTL, the
+ * RR's original TTL according to the RRSIG and the
+ * RRSIG's own TTL, see RFC 4035, Section 5.3.3 */
+ rr->ttl = MIN3(rr->ttl, rrsig->rrsig.original_ttl, rrsig->ttl);
+ rr->expiry = rrsig->rrsig.expiration * USEC_PER_SEC;
+
+ /* Copy over information about the signer and wildcard source of synthesis */
+ rr->n_skip_labels_source = rrsig->n_skip_labels_source;
+ rr->n_skip_labels_signer = rrsig->n_skip_labels_signer;
+ }
+
+ rrsig->expiry = rrsig->rrsig.expiration * USEC_PER_SEC;
+}
+
int dnssec_verify_rrset(
DnsAnswer *a,
- DnsResourceKey *key,
+ const DnsResourceKey *key,
DnsResourceRecord *rrsig,
DnsResourceRecord *dnskey,
usec_t realtime,
DnssecResult *result) {
uint8_t wire_format_name[DNS_WIRE_FOMAT_HOSTNAME_MAX];
- size_t hash_size;
- void *hash;
DnsResourceRecord **list, *rr;
+ const char *source, *name;
gcry_md_hd_t md = NULL;
int r, md_algorithm;
size_t k, n = 0;
+ size_t hash_size;
+ void *hash;
+ bool wildcard;
assert(key);
assert(rrsig);
@@ -527,6 +611,14 @@ int dnssec_verify_rrset(
if (md_algorithm < 0)
return md_algorithm;
+ r = dnssec_rrsig_prepare(rrsig);
+ if (r == -EINVAL) {
+ *result = DNSSEC_INVALID;
+ return r;
+ }
+ if (r < 0)
+ return r;
+
r = dnssec_rrsig_expired(rrsig, realtime);
if (r < 0)
return r;
@@ -535,8 +627,54 @@ int dnssec_verify_rrset(
return 0;
}
+ name = DNS_RESOURCE_KEY_NAME(key);
+
+ /* Some keys may only appear signed in the zone apex, and are invalid anywhere else. (SOA, NS...) */
+ if (dns_type_apex_only(rrsig->rrsig.type_covered)) {
+ r = dns_name_equal(rrsig->rrsig.signer, name);
+ if (r < 0)
+ return r;
+ if (r == 0) {
+ *result = DNSSEC_INVALID;
+ return 0;
+ }
+ }
+
+ /* OTOH DS RRs may not appear in the zone apex, but are valid everywhere else. */
+ if (rrsig->rrsig.type_covered == DNS_TYPE_DS) {
+ r = dns_name_equal(rrsig->rrsig.signer, name);
+ if (r < 0)
+ return r;
+ if (r > 0) {
+ *result = DNSSEC_INVALID;
+ return 0;
+ }
+ }
+
+ /* Determine the "Source of Synthesis" and whether this is a wildcard RRSIG */
+ r = dns_name_suffix(name, rrsig->rrsig.labels, &source);
+ if (r < 0)
+ return r;
+ if (r > 0 && !dns_type_may_wildcard(rrsig->rrsig.type_covered)) {
+ /* We refuse to validate NSEC3 or SOA RRs that are synthesized from wildcards */
+ *result = DNSSEC_INVALID;
+ return 0;
+ }
+ if (r == 1) {
+ /* If we stripped a single label, then let's see if that maybe was "*". If so, we are not really
+ * synthesized from a wildcard, we are the wildcard itself. Treat that like a normal name. */
+ r = dns_name_startswith(name, "*");
+ if (r < 0)
+ return r;
+ if (r > 0)
+ source = name;
+
+ wildcard = r == 0;
+ } else
+ wildcard = r > 0;
+
/* Collect all relevant RRs in a single array, so that we can look at the RRset */
- list = newa(DnsResourceRecord *, a->n_rrs);
+ list = newa(DnsResourceRecord *, dns_answer_size(a));
DNS_ANSWER_FOREACH(rr, a) {
r = dns_resource_key_equal(key, rr->key);
@@ -585,32 +723,30 @@ int dnssec_verify_rrset(
goto finish;
gcry_md_write(md, wire_format_name, r);
+ /* Convert the source of synthesis into wire format */
+ r = dns_name_to_wire_format(source, wire_format_name, sizeof(wire_format_name), true);
+ if (r < 0)
+ goto finish;
+
for (k = 0; k < n; k++) {
- const char *suffix;
size_t l;
+
rr = list[k];
- r = dns_name_suffix(DNS_RESOURCE_KEY_NAME(rr->key), rrsig->rrsig.labels, &suffix);
- if (r < 0)
- goto finish;
- if (r > 0) /* This is a wildcard! */
+ /* Hash the source of synthesis. If this is a wildcard, then prefix it with the *. label */
+ if (wildcard)
gcry_md_write(md, (uint8_t[]) { 1, '*'}, 2);
-
- r = dns_name_to_wire_format(suffix, wire_format_name, sizeof(wire_format_name), true);
- if (r < 0)
- goto finish;
gcry_md_write(md, wire_format_name, r);
md_add_uint16(md, rr->key->type);
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);
@@ -646,7 +782,17 @@ int dnssec_verify_rrset(
if (r < 0)
goto finish;
- *result = r ? DNSSEC_VALIDATED : DNSSEC_INVALID;
+ /* Now, fix the ttl, expiry, and remember the synthesizing source and the signer */
+ if (r > 0)
+ dnssec_fix_rrset_ttl(list, n, rrsig, realtime);
+
+ if (r == 0)
+ *result = DNSSEC_INVALID;
+ else if (wildcard)
+ *result = DNSSEC_VALIDATED_WILDCARD;
+ else
+ *result = DNSSEC_VALIDATED;
+
r = 0;
finish:
@@ -654,7 +800,7 @@ 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);
@@ -671,20 +817,20 @@ 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);
}
int dnssec_key_match_rrsig(const DnsResourceKey *key, DnsResourceRecord *rrsig) {
- int r;
-
assert(key);
assert(rrsig);
@@ -697,51 +843,16 @@ int dnssec_key_match_rrsig(const DnsResourceKey *key, DnsResourceRecord *rrsig)
if (rrsig->rrsig.type_covered != key->type)
return 0;
- /* Make sure signer is a parent of the RRset */
- r = dns_name_endswith(DNS_RESOURCE_KEY_NAME(rrsig->key), rrsig->rrsig.signer);
- if (r <= 0)
- return r;
-
- /* Make sure the owner name has at least as many labels as the "label" fields indicates. */
- r = dns_name_count_labels(DNS_RESOURCE_KEY_NAME(rrsig->key));
- if (r < 0)
- return r;
- if (r < rrsig->rrsig.labels)
- return 0;
-
return dns_name_equal(DNS_RESOURCE_KEY_NAME(rrsig->key), DNS_RESOURCE_KEY_NAME(key));
}
-static int dnssec_fix_rrset_ttl(DnsAnswer *a, const DnsResourceKey *key, DnsResourceRecord *rrsig, usec_t realtime) {
- DnsResourceRecord *rr;
- int r;
-
- assert(key);
- assert(rrsig);
-
- DNS_ANSWER_FOREACH(rr, a) {
- r = dns_resource_key_equal(key, rr->key);
- if (r < 0)
- return r;
- if (r == 0)
- continue;
-
- /* Pick the TTL as the minimum of the RR's TTL, the
- * RR's original TTL according to the RRSIG and the
- * RRSIG's own TTL, see RFC 4035, Section 5.3.3 */
- rr->ttl = MIN3(rr->ttl, rrsig->rrsig.original_ttl, rrsig->ttl);
- rr->expiry = rrsig->rrsig.expiration * USEC_PER_SEC;
- }
-
- return 0;
-}
-
int dnssec_verify_rrset_search(
DnsAnswer *a,
- DnsResourceKey *key,
+ const DnsResourceKey *key,
DnsAnswer *validated_dnskeys,
usec_t realtime,
- DnssecResult *result) {
+ DnssecResult *result,
+ DnsResourceRecord **ret_rrsig) {
bool found_rrsig = false, found_invalid = false, found_expired_rrsig = false, found_unsupported_algorithm = false;
DnsResourceRecord *rrsig;
@@ -777,7 +888,7 @@ 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)
@@ -801,13 +912,13 @@ int dnssec_verify_rrset_search(
switch (one_result) {
case DNSSEC_VALIDATED:
+ case DNSSEC_VALIDATED_WILDCARD:
/* Yay, the RR has been validated,
* return immediately, but fix up the expiry */
- r = dnssec_fix_rrset_ttl(a, key, rrsig, realtime);
- if (r < 0)
- return r;
+ if (ret_rrsig)
+ *ret_rrsig = rrsig;
- *result = DNSSEC_VALIDATED;
+ *result = one_result;
return 0;
case DNSSEC_INVALID:
@@ -852,6 +963,9 @@ int dnssec_verify_rrset_search(
else
*result = DNSSEC_NO_SIGNATURE;
+ if (ret_rrsig)
+ *ret_rrsig = NULL;
+
return 0;
}
@@ -883,23 +997,11 @@ int dnssec_canonicalize(const char *n, char *buffer, size_t buffer_max) {
return -ENOBUFS;
for (;;) {
- size_t i;
-
r = dns_label_unescape(&n, buffer, buffer_max);
if (r < 0)
return r;
if (r == 0)
break;
- if (r > 0) {
- int k;
-
- /* DNSSEC validation is always done on the ASCII version of the label */
- k = dns_label_apply_idna(buffer, r, buffer, buffer_max);
- if (k < 0)
- return k;
- if (k > 0)
- r = k;
- }
if (buffer_max < (size_t) r + 2)
return -ENOBUFS;
@@ -911,11 +1013,7 @@ int dnssec_canonicalize(const char *n, char *buffer, size_t buffer_max) {
if (memchr(buffer, '.', r))
return -EINVAL;
- for (i = 0; i < (size_t) r; i ++) {
- if (buffer[i] >= 'A' && buffer[i] <= 'Z')
- buffer[i] = buffer[i] - 'A' + 'a';
- }
-
+ ascii_strlower_n(buffer, (size_t) r);
buffer[r] = '.';
buffer += r + 1;
@@ -957,7 +1055,7 @@ static int digest_to_gcrypt_md(uint8_t algorithm) {
}
}
-int dnssec_verify_dnskey(DnsResourceRecord *dnskey, DnsResourceRecord *ds) {
+int dnssec_verify_dnskey_by_ds(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 +1073,14 @@ 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 +1104,10 @@ 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);
@@ -1022,7 +1125,7 @@ finish:
return r;
}
-int dnssec_verify_dnskey_search(DnsResourceRecord *dnskey, DnsAnswer *validated_ds) {
+int dnssec_verify_dnskey_by_ds_search(DnsResourceRecord *dnskey, DnsAnswer *validated_ds) {
DnsResourceRecord *ds;
DnsAnswerFlags flags;
int r;
@@ -1039,7 +1142,6 @@ int dnssec_verify_dnskey_search(DnsResourceRecord *dnskey, DnsAnswer *validated_
if (ds->key->type != DNS_TYPE_DS)
continue;
-
if (ds->key->class != dnskey->key->class)
continue;
@@ -1049,7 +1151,9 @@ int dnssec_verify_dnskey_search(DnsResourceRecord *dnskey, DnsAnswer *validated_
if (r == 0)
continue;
- r = dnssec_verify_dnskey(dnskey, ds);
+ r = dnssec_verify_dnskey_by_ds(dnskey, ds, false);
+ if (IN_SET(r, -EKEYREJECTED, -EOPNOTSUPP))
+ return 0; /* The DNSKEY is revoked or otherwise invalid, or we don't support the digest algorithm */
if (r < 0)
return r;
if (r > 0)
@@ -1073,7 +1177,7 @@ 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 +1193,10 @@ 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)
@@ -1144,7 +1250,7 @@ finish:
return r;
}
-static int nsec3_is_good(DnsResourceRecord *rr, DnsAnswerFlags flags, DnsResourceRecord *nsec3) {
+static int nsec3_is_good(DnsResourceRecord *rr, DnsResourceRecord *nsec3) {
const char *a, *b;
int r;
@@ -1164,6 +1270,13 @@ static int nsec3_is_good(DnsResourceRecord *rr, DnsAnswerFlags flags, DnsResourc
if (rr->nsec3.iterations > NSEC3_ITERATIONS_MAX)
return 0;
+ /* Ignore NSEC3 RRs generated from wildcards */
+ if (rr->n_skip_labels_source != 0)
+ return 0;
+ /* Ignore NSEC3 RRs that are located anywhere else than one label below the zone */
+ if (rr->n_skip_labels_signer != 1)
+ return 0;
+
if (!nsec3)
return 1;
@@ -1197,11 +1310,32 @@ static int nsec3_is_good(DnsResourceRecord *rr, DnsAnswerFlags flags, DnsResourc
if (r == 0)
return 0;
+ /* Make sure both have the same parent */
return dns_name_equal(a, b);
}
-static int nsec3_hashed_domain(const DnsResourceRecord *nsec3, const char *domain, const char *zone, char **ret) {
- _cleanup_free_ char *l = NULL, *hashed_domain = NULL;
+static int nsec3_hashed_domain_format(const uint8_t *hashed, size_t hashed_size, const char *zone, char **ret) {
+ _cleanup_free_ char *l = NULL;
+ char *j;
+
+ assert(hashed);
+ assert(hashed_size > 0);
+ assert(zone);
+ assert(ret);
+
+ l = base32hexmem(hashed, hashed_size, false);
+ if (!l)
+ return -ENOMEM;
+
+ j = strjoin(l, ".", zone, NULL);
+ if (!j)
+ return -ENOMEM;
+
+ *ret = j;
+ return (int) hashed_size;
+}
+
+static int nsec3_hashed_domain_make(DnsResourceRecord *nsec3, const char *domain, const char *zone, char **ret) {
uint8_t hashed[DNSSEC_HASH_SIZE_MAX];
int hashed_size;
@@ -1214,18 +1348,7 @@ static int nsec3_hashed_domain(const DnsResourceRecord *nsec3, const char *domai
if (hashed_size < 0)
return hashed_size;
- l = base32hexmem(hashed, hashed_size, false);
- if (!l)
- return -ENOMEM;
-
- hashed_domain = strjoin(l, ".", zone, NULL);
- if (!hashed_domain)
- return -ENOMEM;
-
- *ret = hashed_domain;
- hashed_domain = NULL;
-
- return hashed_size;
+ return nsec3_hashed_domain_format(hashed, (size_t) hashed_size, zone, ret);
}
/* See RFC 5155, Section 8
@@ -1238,17 +1361,16 @@ 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) {
- _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;
+static int dnssec_test_nsec3(DnsAnswer *answer, DnsResourceKey *key, DnssecNsecResult *result, bool *authenticated, uint32_t *ttl) {
+ _cleanup_free_ char *next_closer_domain = NULL, *wildcard_domain = NULL;
+ const char *zone, *p, *pp = NULL, *wildcard;
+ DnsResourceRecord *rr, *enclosure_rr, *zone_rr, *wildcard_rr = NULL;
DnsAnswerFlags flags;
int hashed_size, r;
bool a, no_closer = false, no_wildcard = false, optout = false;
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
@@ -1257,14 +1379,14 @@ static int dnssec_test_nsec3(DnsAnswer *answer, DnsResourceKey *key, DnssecNsecR
* parameters. */
zone = DNS_RESOURCE_KEY_NAME(key);
for (;;) {
- DNS_ANSWER_FOREACH_FLAGS(suffix_rr, flags, answer) {
- r = nsec3_is_good(suffix_rr, flags, NULL);
+ DNS_ANSWER_FOREACH_FLAGS(zone_rr, flags, answer) {
+ r = nsec3_is_good(zone_rr, NULL);
if (r < 0)
return r;
if (r == 0)
continue;
- r = dns_name_equal_skip(DNS_RESOURCE_KEY_NAME(suffix_rr->key), 1, zone);
+ r = dns_name_equal_skip(DNS_RESOURCE_KEY_NAME(zone_rr->key), 1, zone);
if (r < 0)
return r;
if (r > 0)
@@ -1288,7 +1410,7 @@ found_zone:
for (;;) {
_cleanup_free_ char *hashed_domain = NULL;
- hashed_size = nsec3_hashed_domain(suffix_rr, p, zone, &hashed_domain);
+ hashed_size = nsec3_hashed_domain_make(zone_rr, p, zone, &hashed_domain);
if (hashed_size == -EOPNOTSUPP) {
*result = DNSSEC_NSEC_UNSUPPORTED_ALGORITHM;
return 0;
@@ -1298,7 +1420,7 @@ found_zone:
DNS_ANSWER_FOREACH_FLAGS(enclosure_rr, flags, answer) {
- r = nsec3_is_good(enclosure_rr, flags, suffix_rr);
+ r = nsec3_is_good(enclosure_rr, zone_rr);
if (r < 0)
return r;
if (r == 0)
@@ -1357,45 +1479,41 @@ found_closest_encloser:
else
*result = DNSSEC_NSEC_NODATA;
- *authenticated = a;
+ if (authenticated)
+ *authenticated = a;
+ if (ttl)
+ *ttl = enclosure_rr->ttl;
return 0;
}
/* Prove that there is no next closer and whether or not there is a wildcard domain. */
- wildcard = strappend("*.", p);
- if (!wildcard)
- return -ENOMEM;
-
- r = nsec3_hashed_domain(enclosure_rr, wildcard, zone, &wildcard_domain);
+ wildcard = strjoina("*.", p);
+ r = nsec3_hashed_domain_make(enclosure_rr, wildcard, zone, &wildcard_domain);
if (r < 0)
return r;
if (r != hashed_size)
return -EBADMSG;
- r = nsec3_hashed_domain(enclosure_rr, pp, zone, &next_closer_domain);
+ r = nsec3_hashed_domain_make(enclosure_rr, pp, zone, &next_closer_domain);
if (r < 0)
return r;
if (r != hashed_size)
return -EBADMSG;
DNS_ANSWER_FOREACH_FLAGS(rr, flags, answer) {
- _cleanup_free_ char *label = NULL, *next_hashed_domain = NULL;
+ _cleanup_free_ char *next_hashed_domain = NULL;
- r = nsec3_is_good(rr, flags, suffix_rr);
+ r = nsec3_is_good(rr, zone_rr);
if (r < 0)
return r;
if (r == 0)
continue;
- label = base32hexmem(rr->nsec3.next_hashed_name, rr->nsec3.next_hashed_name_size, false);
- if (!label)
- return -ENOMEM;
-
- next_hashed_domain = strjoin(label, ".", zone, NULL);
- if (!next_hashed_domain)
- return -ENOMEM;
+ r = nsec3_hashed_domain_format(rr->nsec3.next_hashed_name, rr->nsec3.next_hashed_name_size, zone, &next_hashed_domain);
+ if (r < 0)
+ return r;
r = dns_name_between(DNS_RESOURCE_KEY_NAME(rr->key), next_closer_domain, next_hashed_domain);
if (r < 0)
@@ -1440,7 +1558,6 @@ found_closest_encloser:
if (!no_closer) {
*result = DNSSEC_NSEC_NO_RR;
-
return 0;
}
@@ -1476,80 +1593,531 @@ 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) {
- DnsResourceRecord *rr;
- bool have_nsec3 = false;
+static int dnssec_nsec_wildcard_equal(DnsResourceRecord *rr, const char *name) {
+ char label[DNS_LABEL_MAX];
+ const char *n;
+ int r;
+
+ assert(rr);
+ assert(rr->key->type == DNS_TYPE_NSEC);
+
+ /* Checks whether the specified RR has a name beginning in "*.", and if the rest is a suffix of our name */
+
+ if (rr->n_skip_labels_source != 1)
+ return 0;
+
+ n = DNS_RESOURCE_KEY_NAME(rr->key);
+ r = dns_label_unescape(&n, label, sizeof(label));
+ if (r <= 0)
+ return r;
+ if (r != 1 || label[0] != '*')
+ return 0;
+
+ return dns_name_endswith(name, n);
+}
+
+static int dnssec_nsec_in_path(DnsResourceRecord *rr, const char *name) {
+ const char *nn, *common_suffix;
+ int r;
+
+ assert(rr);
+ assert(rr->key->type == DNS_TYPE_NSEC);
+
+ /* Checks whether the specified nsec RR indicates that name is an empty non-terminal (ENT)
+ *
+ * A couple of examples:
+ *
+ * NSEC bar → waldo.foo.bar: indicates that foo.bar exists and is an ENT
+ * NSEC waldo.foo.bar → yyy.zzz.xoo.bar: indicates that xoo.bar and zzz.xoo.bar exist and are ENTs
+ * NSEC yyy.zzz.xoo.bar → bar: indicates pretty much nothing about ENTs
+ */
+
+ /* First, determine parent of next domain. */
+ nn = rr->nsec.next_domain_name;
+ r = dns_name_parent(&nn);
+ if (r <= 0)
+ return r;
+
+ /* If the name we just determined is not equal or child of the name we are interested in, then we can't say
+ * anything at all. */
+ r = dns_name_endswith(nn, name);
+ if (r <= 0)
+ return r;
+
+ /* If the name we we are interested in is not a prefix of the common suffix of the NSEC RR's owner and next domain names, then we can't say anything either. */
+ r = dns_name_common_suffix(DNS_RESOURCE_KEY_NAME(rr->key), rr->nsec.next_domain_name, &common_suffix);
+ if (r < 0)
+ return r;
+
+ return dns_name_endswith(name, common_suffix);
+}
+
+static int dnssec_nsec_from_parent_zone(DnsResourceRecord *rr, const char *name) {
+ int r;
+
+ assert(rr);
+ assert(rr->key->type == DNS_TYPE_NSEC);
+
+ /* Checks whether this NSEC originates to the parent zone or the child zone. */
+
+ r = dns_name_parent(&name);
+ if (r <= 0)
+ return r;
+
+ r = dns_name_equal(name, DNS_RESOURCE_KEY_NAME(rr->key));
+ if (r <= 0)
+ return r;
+
+ /* DNAME, and NS without SOA is an indication for a delegation. */
+ if (bitmap_isset(rr->nsec.types, DNS_TYPE_DNAME))
+ return 1;
+
+ if (bitmap_isset(rr->nsec.types, DNS_TYPE_NS) && !bitmap_isset(rr->nsec.types, DNS_TYPE_SOA))
+ return 1;
+
+ return 0;
+}
+
+static int dnssec_nsec_covers(DnsResourceRecord *rr, const char *name) {
+ const char *common_suffix, *p;
+ int r;
+
+ assert(rr);
+ assert(rr->key->type == DNS_TYPE_NSEC);
+
+ /* Checks whether the "Next Closer" is witin the space covered by the specified RR. */
+
+ r = dns_name_common_suffix(DNS_RESOURCE_KEY_NAME(rr->key), rr->nsec.next_domain_name, &common_suffix);
+ if (r < 0)
+ return r;
+
+ for (;;) {
+ p = name;
+ r = dns_name_parent(&name);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ return 0;
+
+ r = dns_name_equal(name, common_suffix);
+ if (r < 0)
+ return r;
+ if (r > 0)
+ break;
+ }
+
+ /* p is now the "Next Closer". */
+
+ return dns_name_between(DNS_RESOURCE_KEY_NAME(rr->key), p, rr->nsec.next_domain_name);
+}
+
+static int dnssec_nsec_covers_wildcard(DnsResourceRecord *rr, const char *name) {
+ const char *common_suffix, *wc;
+ int r;
+
+ assert(rr);
+ assert(rr->key->type == DNS_TYPE_NSEC);
+
+ /* Checks whether the "Wildcard at the Closest Encloser" is within the space covered by the specified
+ * RR. Specifically, checks whether 'name' has the common suffix of the NSEC RR's owner and next names as
+ * suffix, and whether the NSEC covers the name generated by that suffix prepended with an asterisk label.
+ *
+ * NSEC bar → waldo.foo.bar: indicates that *.bar and *.foo.bar do not exist
+ * NSEC waldo.foo.bar → yyy.zzz.xoo.bar: indicates that *.xoo.bar and *.zzz.xoo.bar do not exist (and more ...)
+ * NSEC yyy.zzz.xoo.bar → bar: indicates that a number of wildcards don#t exist either...
+ */
+
+ r = dns_name_common_suffix(DNS_RESOURCE_KEY_NAME(rr->key), rr->nsec.next_domain_name, &common_suffix);
+ if (r < 0)
+ return r;
+
+ /* If the common suffix is not shared by the name we are interested in, it has nothing to say for us. */
+ r = dns_name_endswith(name, common_suffix);
+ if (r <= 0)
+ return r;
+
+ wc = strjoina("*.", common_suffix, NULL);
+ return dns_name_between(DNS_RESOURCE_KEY_NAME(rr->key), wc, rr->nsec.next_domain_name);
+}
+
+int dnssec_nsec_test(DnsAnswer *answer, DnsResourceKey *key, DnssecNsecResult *result, bool *authenticated, uint32_t *ttl) {
+ bool have_nsec3 = false, covering_rr_authenticated = false, wildcard_rr_authenticated = false;
+ DnsResourceRecord *rr, *covering_rr = NULL, *wildcard_rr = NULL;
DnsAnswerFlags flags;
+ const char *name;
int r;
assert(key);
assert(result);
- assert(authenticated);
/* Look for any NSEC/NSEC3 RRs that say something about the specified key. */
+ name = DNS_RESOURCE_KEY_NAME(key);
+
DNS_ANSWER_FOREACH_FLAGS(rr, flags, answer) {
if (rr->key->class != key->class)
continue;
- switch (rr->key->type) {
+ have_nsec3 = have_nsec3 || (rr->key->type == DNS_TYPE_NSEC3);
- case DNS_TYPE_NSEC:
+ if (rr->key->type != DNS_TYPE_NSEC)
+ continue;
+
+ /* The following checks only make sense for NSEC RRs that are not expanded from a wildcard */
+ r = dns_resource_record_is_synthetic(rr);
+ if (r < 0)
+ return r;
+ if (r > 0)
+ continue;
- r = dns_name_equal(DNS_RESOURCE_KEY_NAME(rr->key), DNS_RESOURCE_KEY_NAME(key));
+ /* Check if this is a direct match. If so, we have encountered a NODATA case */
+ r = dns_name_equal(DNS_RESOURCE_KEY_NAME(rr->key), name);
+ if (r < 0)
+ return r;
+ if (r == 0) {
+ /* If it's not a direct match, maybe it's a wild card match? */
+ r = dnssec_nsec_wildcard_equal(rr, name);
if (r < 0)
return r;
- if (r > 0) {
- if (bitmap_isset(rr->nsec.types, key->type))
- *result = DNSSEC_NSEC_FOUND;
- else if (bitmap_isset(rr->nsec.types, DNS_TYPE_CNAME))
- *result = DNSSEC_NSEC_CNAME;
- else
- *result = DNSSEC_NSEC_NODATA;
- *authenticated = flags & DNS_ANSWER_AUTHENTICATED;
- return 0;
+ }
+ if (r > 0) {
+ if (key->type == DNS_TYPE_DS) {
+ /* If we look for a DS RR and the server sent us the NSEC RR of the child zone
+ * we have a problem. For DS RRs we want the NSEC RR from the parent */
+ if (bitmap_isset(rr->nsec.types, DNS_TYPE_SOA))
+ continue;
+ } else {
+ /* For all RR types, ensure that if NS is set SOA is set too, so that we know
+ * we got the child's NSEC. */
+ if (bitmap_isset(rr->nsec.types, DNS_TYPE_NS) &&
+ !bitmap_isset(rr->nsec.types, DNS_TYPE_SOA))
+ continue;
}
- r = dns_name_between(DNS_RESOURCE_KEY_NAME(rr->key), DNS_RESOURCE_KEY_NAME(key), rr->nsec.next_domain_name);
- if (r < 0)
- return r;
- if (r > 0) {
- *result = DNSSEC_NSEC_NXDOMAIN;
+ if (bitmap_isset(rr->nsec.types, key->type))
+ *result = DNSSEC_NSEC_FOUND;
+ else if (bitmap_isset(rr->nsec.types, DNS_TYPE_CNAME))
+ *result = DNSSEC_NSEC_CNAME;
+ else
+ *result = DNSSEC_NSEC_NODATA;
+
+ if (authenticated)
*authenticated = flags & DNS_ANSWER_AUTHENTICATED;
- return 0;
- }
- break;
+ if (ttl)
+ *ttl = rr->ttl;
- case DNS_TYPE_NSEC3:
- have_nsec3 = true;
- break;
+ return 0;
+ }
+
+ /* Check if the name we are looking for is an empty non-terminal within the owner or next name
+ * of the NSEC RR. */
+ r = dnssec_nsec_in_path(rr, name);
+ if (r < 0)
+ return r;
+ if (r > 0) {
+ *result = DNSSEC_NSEC_NODATA;
+
+ if (authenticated)
+ *authenticated = flags & DNS_ANSWER_AUTHENTICATED;
+ if (ttl)
+ *ttl = rr->ttl;
+
+ return 0;
}
+
+ /* The following two "covering" checks, are not useful if the NSEC is from the parent */
+ r = dnssec_nsec_from_parent_zone(rr, name);
+ if (r < 0)
+ return r;
+ if (r > 0)
+ continue;
+
+ /* Check if this NSEC RR proves the absence of an explicit RR under this name */
+ r = dnssec_nsec_covers(rr, name);
+ if (r < 0)
+ return r;
+ if (r > 0 && (!covering_rr || !covering_rr_authenticated)) {
+ covering_rr = rr;
+ covering_rr_authenticated = flags & DNS_ANSWER_AUTHENTICATED;
+ }
+
+ /* Check if this NSEC RR proves the absence of a wildcard RR under this name */
+ r = dnssec_nsec_covers_wildcard(rr, name);
+ if (r < 0)
+ return r;
+ if (r > 0 && (!wildcard_rr || !wildcard_rr_authenticated)) {
+ wildcard_rr = rr;
+ wildcard_rr_authenticated = flags & DNS_ANSWER_AUTHENTICATED;
+ }
+ }
+
+ if (covering_rr && wildcard_rr) {
+ /* If we could prove that neither the name itself, nor the wildcard at the closest encloser exists, we
+ * proved the NXDOMAIN case. */
+ *result = DNSSEC_NSEC_NXDOMAIN;
+
+ if (authenticated)
+ *authenticated = covering_rr_authenticated && wildcard_rr_authenticated;
+ if (ttl)
+ *ttl = MIN(covering_rr->ttl, wildcard_rr->ttl);
+
+ return 0;
}
/* 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;
return 0;
}
-static const char* const dnssec_mode_table[_DNSSEC_MODE_MAX] = {
- [DNSSEC_NO] = "no",
- [DNSSEC_DOWNGRADE_OK] = "downgrade-ok",
- [DNSSEC_YES] = "yes",
-};
-DEFINE_STRING_TABLE_LOOKUP(dnssec_mode, DnssecMode);
+int dnssec_nsec_test_enclosed(DnsAnswer *answer, uint16_t type, const char *name, const char *zone, bool *authenticated) {
+ DnsResourceRecord *rr;
+ DnsAnswerFlags flags;
+ int r;
+
+ assert(name);
+ assert(zone);
+
+ /* Checks whether there's an NSEC/NSEC3 that proves that the specified 'name' is non-existing in the specified
+ * 'zone'. The 'zone' must be a suffix of the 'name'. */
+
+ DNS_ANSWER_FOREACH_FLAGS(rr, flags, answer) {
+ bool found = false;
+
+ if (rr->key->type != type && type != DNS_TYPE_ANY)
+ continue;
+
+ switch (rr->key->type) {
+
+ case DNS_TYPE_NSEC:
+
+ /* We only care for NSEC RRs from the indicated zone */
+ r = dns_resource_record_is_signer(rr, zone);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ continue;
+
+ r = dns_name_between(DNS_RESOURCE_KEY_NAME(rr->key), name, rr->nsec.next_domain_name);
+ if (r < 0)
+ return r;
+
+ found = r > 0;
+ break;
+
+ case DNS_TYPE_NSEC3: {
+ _cleanup_free_ char *hashed_domain = NULL, *next_hashed_domain = NULL;
+
+ /* We only care for NSEC3 RRs from the indicated zone */
+ r = dns_resource_record_is_signer(rr, zone);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ continue;
+
+ r = nsec3_is_good(rr, NULL);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ break;
+
+ /* Format the domain we are testing with the NSEC3 RR's hash function */
+ r = nsec3_hashed_domain_make(
+ rr,
+ name,
+ zone,
+ &hashed_domain);
+ if (r < 0)
+ return r;
+ if ((size_t) r != rr->nsec3.next_hashed_name_size)
+ break;
+
+ /* Format the NSEC3's next hashed name as proper domain name */
+ r = nsec3_hashed_domain_format(
+ rr->nsec3.next_hashed_name,
+ rr->nsec3.next_hashed_name_size,
+ zone,
+ &next_hashed_domain);
+ if (r < 0)
+ return r;
+
+ r = dns_name_between(DNS_RESOURCE_KEY_NAME(rr->key), hashed_domain, next_hashed_domain);
+ if (r < 0)
+ return r;
+
+ found = r > 0;
+ break;
+ }
+
+ default:
+ continue;
+ }
+
+ if (found) {
+ if (authenticated)
+ *authenticated = flags & DNS_ANSWER_AUTHENTICATED;
+ return 1;
+ }
+ }
+
+ return 0;
+}
+
+static int dnssec_test_positive_wildcard_nsec3(
+ DnsAnswer *answer,
+ const char *name,
+ const char *source,
+ const char *zone,
+ bool *authenticated) {
+
+ const char *next_closer = NULL;
+ int r;
+
+ /* Run a positive NSEC3 wildcard proof. Specifically:
+ *
+ * A proof that the the "next closer" of the generating wildcard does not exist.
+ *
+ * Note a key difference between the NSEC3 and NSEC versions of the proof. NSEC RRs don't have to exist for
+ * empty non-transients. NSEC3 RRs however have to. This means it's sufficient to check if the next closer name
+ * exists for the NSEC3 RR and we are done.
+ *
+ * To prove that a.b.c.d.e.f is rightfully synthesized from a wildcard *.d.e.f all we have to check is that
+ * c.d.e.f does not exist. */
+
+ for (;;) {
+ next_closer = name;
+ r = dns_name_parent(&name);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ return 0;
+
+ r = dns_name_equal(name, source);
+ if (r < 0)
+ return r;
+ if (r > 0)
+ break;
+ }
+
+ return dnssec_nsec_test_enclosed(answer, DNS_TYPE_NSEC3, next_closer, zone, authenticated);
+}
+
+static int dnssec_test_positive_wildcard_nsec(
+ DnsAnswer *answer,
+ const char *name,
+ const char *source,
+ const char *zone,
+ bool *_authenticated) {
+
+ bool authenticated = true;
+ int r;
+
+ /* Run a positive NSEC wildcard proof. Specifically:
+ *
+ * A proof that there's neither a wildcard name nor a non-wildcard name that is a suffix of the name "name" and
+ * a prefix of the synthesizing source "source" in the zone "zone".
+ *
+ * See RFC 5155, Section 8.8 and RFC 4035, Section 5.3.4
+ *
+ * Note that if we want to prove that a.b.c.d.e.f is rightfully synthesized from a wildcard *.d.e.f, then we
+ * have to prove that none of the following exist:
+ *
+ * 1) a.b.c.d.e.f
+ * 2) *.b.c.d.e.f
+ * 3) b.c.d.e.f
+ * 4) *.c.d.e.f
+ * 5) c.d.e.f
+ *
+ */
+
+ for (;;) {
+ _cleanup_free_ char *wc = NULL;
+ bool a = false;
+
+ /* Check if there's an NSEC or NSEC3 RR that proves that the mame we determined is really non-existing,
+ * i.e between the owner name and the next name of an NSEC RR. */
+ r = dnssec_nsec_test_enclosed(answer, DNS_TYPE_NSEC, name, zone, &a);
+ if (r <= 0)
+ return r;
+
+ authenticated = authenticated && a;
+
+ /* Strip one label off */
+ r = dns_name_parent(&name);
+ if (r <= 0)
+ return r;
+
+ /* Did we reach the source of synthesis? */
+ r = dns_name_equal(name, source);
+ if (r < 0)
+ return r;
+ if (r > 0) {
+ /* Successful exit */
+ *_authenticated = authenticated;
+ return 1;
+ }
+
+ /* Safety check, that the source of synthesis is still our suffix */
+ r = dns_name_endswith(name, source);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ return -EBADMSG;
+
+ /* Replace the label we stripped off with an asterisk */
+ wc = strappend("*.", name);
+ if (!wc)
+ return -ENOMEM;
+
+ /* And check if the proof holds for the asterisk name, too */
+ r = dnssec_nsec_test_enclosed(answer, DNS_TYPE_NSEC, wc, zone, &a);
+ if (r <= 0)
+ return r;
+
+ authenticated = authenticated && a;
+ /* In the next iteration we'll check the non-asterisk-prefixed version */
+ }
+}
+
+int dnssec_test_positive_wildcard(
+ DnsAnswer *answer,
+ const char *name,
+ const char *source,
+ const char *zone,
+ bool *authenticated) {
+
+ int r;
+
+ assert(name);
+ assert(source);
+ assert(zone);
+ assert(authenticated);
+
+ r = dns_answer_contains_zone_nsec3(answer, zone);
+ if (r < 0)
+ return r;
+ if (r > 0)
+ return dnssec_test_positive_wildcard_nsec3(answer, name, source, zone, authenticated);
+ else
+ return dnssec_test_positive_wildcard_nsec(answer, name, source, zone, authenticated);
+}
static const char* const dnssec_result_table[_DNSSEC_RESULT_MAX] = {
[DNSSEC_VALIDATED] = "validated",
+ [DNSSEC_VALIDATED_WILDCARD] = "validated-wildcard",
[DNSSEC_INVALID] = "invalid",
[DNSSEC_SIGNATURE_EXPIRED] = "signature-expired",
[DNSSEC_UNSUPPORTED_ALGORITHM] = "unsupported-algorithm",
generated by cgit v1.2.3-54-g00ecf (git 2.45.2) at 2025-04-24 18:23:36 +0000