2495. [bug] Tighten RRSIG checks. [RT #18795]

CHANGES

@@ -1,3 +1,5 @@
+2495.	[bug]		Tighten RRSIG checks. [RT #18795]
+
 2494.	[bug]		isc/radix.h, dns/sdlz.h and dns/dlz.h were not being
 			installed. [RT #18826]
 

bin/dnssec/dnssec-signzone.c

@@ -29,7 +29,7 @@
  * IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  */
 
-/* $Id: dnssec-signzone.c,v 1.208 2008/09/26 01:27:08 marka Exp $ */
+/* $Id: dnssec-signzone.c,v 1.209 2008/11/14 22:53:46 marka Exp $ */
 
 /*! \file */
 
@@ -2784,6 +2784,9 @@ main(int argc, char *argv[]) {
 				fatal("cannot load dnskey %s: %s", argv[i],
 				      isc_result_totext(result));
 
+			if (!dns_name_equal(gorigin, dst_key_name(newkey)))
+				fatal("key %s not at origin\n", argv[i]);
+
 			key = ISC_LIST_HEAD(keylist);
 			while (key != NULL) {
 				dst_key_t *dkey = key->key;
@@ -2821,6 +2824,9 @@ main(int argc, char *argv[]) {
 			fatal("cannot load dnskey %s: %s", dskeyfile[i],
 			      isc_result_totext(result));
 
+		if (!dns_name_equal(gorigin, dst_key_name(newkey)))
+			fatal("key %s not at origin\n", dskeyfile[i]);
+
 		key = ISC_LIST_HEAD(keylist);
 		while (key != NULL) {
 			dst_key_t *dkey = key->key;

lib/dns/dnssec.c

@@ -16,7 +16,7 @@
  */
 
 /*
- * $Id: dnssec.c,v 1.91 2007/09/14 04:32:50 marka Exp $
+ * $Id: dnssec.c,v 1.92 2008/11/14 22:53:46 marka Exp $
  */
 
 /*! \file */
@@ -366,6 +366,9 @@ dns_dnssec_verify2(dns_name_t *name, dns_rdataset_t *set, dst_key_t *key,
 	if (ret != ISC_R_SUCCESS)
 		return (ret);
 
+	if (set->type != sig.covered)
+		return (DNS_R_SIGINVALID);
+
 	if (isc_serial_lt(sig.timeexpire, sig.timesigned))
 		return (DNS_R_SIGINVALID);
 
@@ -381,6 +384,27 @@ dns_dnssec_verify2(dns_name_t *name, dns_rdataset_t *set, dst_key_t *key,
 			return (DNS_R_SIGEXPIRED);
 	}
 
+	/*
+	 * NS, SOA and DNSSKEY records are signed by their owner.
+	 * DS records are signed by the parent.
+	 */
+	switch (set->type) {
+	case dns_rdatatype_ns:
+	case dns_rdatatype_soa:
+	case dns_rdatatype_dnskey:
+		if (!dns_name_equal(name, &sig.signer))
+			return (DNS_R_SIGINVALID);
+		break;
+	case dns_rdatatype_ds:
+		if (dns_name_equal(name, &sig.signer))
+			return (DNS_R_SIGINVALID);
+		/* FALLTHROUGH */
+	default:
+		if (!dns_name_issubdomain(name, &sig.signer))
+			return (DNS_R_SIGINVALID);
+		break;
+	}
+
 	/*
 	 * Is the key allowed to sign data?
 	 */
@@ -541,6 +565,9 @@ dns_dnssec_findzonekeys2(dns_db_t *db, dns_dbversion_t *ver,
 		if (!is_zone_key(pubkey) ||
 		    (dst_key_flags(pubkey) & DNS_KEYTYPE_NOAUTH) != 0)
 			goto next;
+		/* Corrupted .key file? */
+		if (!dns_name_equal(name, dst_key_name(pubkey)))
+			goto next;
 		keys[count] = NULL;
 		result = dst_key_fromfile(dst_key_name(pubkey),
 					  dst_key_id(pubkey),

lib/dns/dst_api.c

@@ -31,7 +31,7 @@
 
 /*
  * Principal Author: Brian Wellington
- * $Id: dst_api.c,v 1.15 2008/09/24 02:46:22 marka Exp $
+ * $Id: dst_api.c,v 1.16 2008/11/14 22:53:46 marka Exp $
  */
 
 /*! \file */
@@ -997,6 +997,13 @@ dst_key_read_public(const char *filename, int type,
 	NEXTTOKEN(lex, opt, &token);
 	if (token.type != isc_tokentype_string)
 		BADTOKEN();
+
+	/*
+	 * We don't support "@" in .key files.
+	 */
+	if (!strcmp(DST_AS_STR(token), "@"))
+		BADTOKEN();
+
 	dns_fixedname_init(&name);
 	isc_buffer_init(&b, DST_AS_STR(token), strlen(DST_AS_STR(token)));
 	isc_buffer_add(&b, strlen(DST_AS_STR(token)));

lib/dns/validator.c

@@ -15,7 +15,7 @@
  * PERFORMANCE OF THIS SOFTWARE.
  */
 
-/* $Id: validator.c,v 1.162 2008/09/24 02:46:22 marka Exp $ */
+/* $Id: validator.c,v 1.163 2008/11/14 22:53:46 marka Exp $ */
 
 #include <config.h>
 
@@ -1544,6 +1544,23 @@ get_key(dns_validator_t *val, dns_rdata_rrsig_t *siginfo) {
 		 */
 		if (dns_rdatatype_atparent(val->event->rdataset->type))
 			return (DNS_R_CONTINUE);
+	} else {
+		/*
+		 * SOA and NS RRsets can only be signed by a key with	
+		 * the same name.
+		 */
+		if (val->event->rdataset->type == dns_rdatatype_soa ||
+		    val->event->rdataset->type == dns_rdatatype_ns) {
+			const char *typename;
+
+			if (val->event->rdataset->type == dns_rdatatype_soa)
+				typename = "SOA";
+			else
+				typename = "NS";
+			validator_log(val, ISC_LOG_DEBUG(3),
+				      "%s signer mismatch", typename);
+			return (DNS_R_CONTINUE);
+		}
 	}
 
 	/*
@@ -2115,6 +2132,10 @@ validatezonekey(dns_validator_t *val) {
 					     &sigrdata);
 			result = dns_rdata_tostruct(&sigrdata, &sig, NULL);
 			RUNTIME_CHECK(result == ISC_R_SUCCESS);
+
+			if (!dns_name_equal(val->event->name, &sig.signer))
+				continue;
+
 			result = dns_keytable_findkeynode(val->keytable,
 							  val->event->name,
 							  sig.algorithm,
@@ -2355,7 +2376,11 @@ validatezonekey(dns_validator_t *val) {
 			if (ds.key_tag != sig.keyid ||
 			    ds.algorithm != sig.algorithm)
 				continue;
-
+			if (!dns_name_equal(val->event->name, &sig.signer)) {
+				validator_log(val, ISC_LOG_DEBUG(3),
+					      "DNSKEY signer mismatch");
+				continue;
+			}
 			dstkey = NULL;
 			result = dns_dnssec_keyfromrdata(val->event->name,
 							 &keyrdata,