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-rw-r--r--src/resolve/resolved-dns-dnssec.c158
-rw-r--r--src/resolve/resolved-dns-rr.c58
-rw-r--r--src/resolve/resolved-dns-rr.h14
-rw-r--r--src/resolve/resolved-dns-transaction.c4
4 files changed, 182 insertions, 52 deletions
diff --git a/src/resolve/resolved-dns-dnssec.c b/src/resolve/resolved-dns-dnssec.c
index b6fb362daa..37fc3150f0 100644
--- a/src/resolve/resolved-dns-dnssec.c
+++ b/src/resolve/resolved-dns-dnssec.c
@@ -430,6 +430,57 @@ 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;
@@ -499,6 +550,35 @@ 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,
const DnsResourceKey *key,
@@ -536,6 +616,14 @@ 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;
@@ -699,12 +787,17 @@ int dnssec_verify_rrset(
if (r < 0)
goto finish;
- if (!r)
+ /* 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:
@@ -743,8 +836,6 @@ int dnssec_rrsig_match_dnskey(DnsResourceRecord *rrsig, DnsResourceRecord *dnske
}
int dnssec_key_match_rrsig(const DnsResourceKey *key, DnsResourceRecord *rrsig) {
- int r;
-
assert(key);
assert(rrsig);
@@ -757,45 +848,9 @@ 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,
const DnsResourceKey *key,
@@ -865,10 +920,6 @@ int dnssec_verify_rrset_search(
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;
@@ -1658,15 +1709,17 @@ int dnssec_nsec_test_enclosed(DnsAnswer *answer, uint16_t type, const char *name
if (rr->key->type != type && type != DNS_TYPE_ANY)
continue;
- r = dns_name_endswith(DNS_RESOURCE_KEY_NAME(rr->key), zone);
- if (r < 0)
- return r;
- if (r == 0)
- 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;
@@ -1677,6 +1730,13 @@ int dnssec_nsec_test_enclosed(DnsAnswer *answer, uint16_t type, const char *name
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;
diff --git a/src/resolve/resolved-dns-rr.c b/src/resolve/resolved-dns-rr.c
index dbf840157f..53fd708365 100644
--- a/src/resolve/resolved-dns-rr.c
+++ b/src/resolve/resolved-dns-rr.c
@@ -344,6 +344,7 @@ DnsResourceRecord* dns_resource_record_new(DnsResourceKey *key) {
rr->n_ref = 1;
rr->key = dns_resource_key_ref(key);
rr->expiry = USEC_INFINITY;
+ rr->n_skip_labels_signer = rr->n_skip_labels_source = (unsigned) -1;
return rr;
}
@@ -1085,6 +1086,63 @@ int dns_resource_record_to_wire_format(DnsResourceRecord *rr, bool canonical) {
return 0;
}
+int dns_resource_record_signer(DnsResourceRecord *rr, const char **ret) {
+ const char *n;
+ int r;
+
+ assert(rr);
+ assert(ret);
+
+ /* Returns the RRset's signer, if it is known. */
+
+ if (rr->n_skip_labels_signer == (unsigned) -1)
+ return -ENODATA;
+
+ n = DNS_RESOURCE_KEY_NAME(rr->key);
+ r = dns_name_skip(n, rr->n_skip_labels_signer, &n);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ return -EINVAL;
+
+ *ret = n;
+ return 0;
+}
+
+int dns_resource_record_source(DnsResourceRecord *rr, const char **ret) {
+ const char *n;
+ int r;
+
+ assert(rr);
+ assert(ret);
+
+ /* Returns the RRset's synthesizing source, if it is known. */
+
+ if (rr->n_skip_labels_source == (unsigned) -1)
+ return -ENODATA;
+
+ n = DNS_RESOURCE_KEY_NAME(rr->key);
+ r = dns_name_skip(n, rr->n_skip_labels_source, &n);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ return -EINVAL;
+
+ *ret = n;
+ return 0;
+}
+
+int dns_resource_record_is_signer(DnsResourceRecord *rr, const char *zone) {
+ const char *signer;
+ int r;
+
+ r = dns_resource_record_signer(rr, &signer);
+ if (r < 0)
+ return r;
+
+ return dns_name_equal(zone, signer);
+}
+
static void dns_resource_record_hash_func(const void *i, struct siphash *state) {
const DnsResourceRecord *rr = i;
diff --git a/src/resolve/resolved-dns-rr.h b/src/resolve/resolved-dns-rr.h
index fe29a41566..8e7bfaa7c7 100644
--- a/src/resolve/resolved-dns-rr.h
+++ b/src/resolve/resolved-dns-rr.h
@@ -108,14 +108,24 @@ struct DnsTxtItem {
struct DnsResourceRecord {
unsigned n_ref;
DnsResourceKey *key;
+
char *to_string;
+
uint32_t ttl;
usec_t expiry; /* RRSIG signature expiry */
+
+ /* How many labels to strip to determine "signer" of the RRSIG (aka, the zone). -1 if not signed. */
+ unsigned n_skip_labels_signer;
+ /* How many labels to strip to determine "synthesizing source" of this RR, i.e. the wildcard's immediate parent. -1 if not signed. */
+ unsigned n_skip_labels_source;
+
bool unparseable:1;
+
bool wire_format_canonical:1;
void *wire_format;
size_t wire_format_size;
size_t wire_format_rdata_offset;
+
union {
struct {
void *data;
@@ -296,6 +306,10 @@ DEFINE_TRIVIAL_CLEANUP_FUNC(DnsResourceRecord*, dns_resource_record_unref);
int dns_resource_record_to_wire_format(DnsResourceRecord *rr, bool canonical);
+int dns_resource_record_signer(DnsResourceRecord *rr, const char **ret);
+int dns_resource_record_source(DnsResourceRecord *rr, const char **ret);
+int dns_resource_record_is_signer(DnsResourceRecord *rr, const char *zone);
+
DnsTxtItem *dns_txt_item_free_all(DnsTxtItem *i);
bool dns_txt_item_equal(DnsTxtItem *a, DnsTxtItem *b);
diff --git a/src/resolve/resolved-dns-transaction.c b/src/resolve/resolved-dns-transaction.c
index c7d2d82ecf..8fe581b33c 100644
--- a/src/resolve/resolved-dns-transaction.c
+++ b/src/resolve/resolved-dns-transaction.c
@@ -2537,11 +2537,9 @@ int dns_transaction_validate_dnssec(DnsTransaction *t) {
* that no matching non-wildcard RR exists.*/
/* First step, determine the source of synthesis */
- r = dns_name_suffix(DNS_RESOURCE_KEY_NAME(rr->key), rrsig->rrsig.labels, &source);
+ r = dns_resource_record_source(rrsig, &source);
if (r < 0)
return r;
- if (r == 0)
- return -EBADMSG;
r = dnssec_test_positive_wildcard(
validated,
generated by cgit v1.2.3-54-g00ecf (git 2.45.2) at 2024-11-04 14:27:52 +0000