Esempio n. 1
0
isc_result_t
dst_key_todns(const dst_key_t *key, isc_buffer_t *target) {
	REQUIRE(dst_initialized == ISC_TRUE);
	REQUIRE(VALID_KEY(key));
	REQUIRE(target != NULL);

	CHECKALG(key->key_alg);

	if (key->func->todns == NULL)
		return (DST_R_UNSUPPORTEDALG);

	if (isc_buffer_availablelength(target) < 4)
		return (ISC_R_NOSPACE);
	isc_buffer_putuint16(target, (isc_uint16_t)(key->key_flags & 0xffff));
	isc_buffer_putuint8(target, (isc_uint8_t)key->key_proto);
	isc_buffer_putuint8(target, (isc_uint8_t)key->key_alg);

	if (key->key_flags & DNS_KEYFLAG_EXTENDED) {
		if (isc_buffer_availablelength(target) < 2)
			return (ISC_R_NOSPACE);
		isc_buffer_putuint16(target,
				     (isc_uint16_t)((key->key_flags >> 16)
						    & 0xffff));
	}

	if (key->keydata.generic == NULL) /*%< NULL KEY */
		return (ISC_R_SUCCESS);

	return (key->func->todns(key, target));
}
Esempio n. 2
0
static inline isc_result_t
copy_rdataset(dns_rdataset_t *rdataset, isc_buffer_t *buffer) {
	isc_result_t result;
	unsigned int count;
	isc_region_t ar, r;
	dns_rdata_t rdata = DNS_RDATA_INIT;

	/*
	 * Copy the rdataset count to the buffer.
	 */
	isc_buffer_availableregion(buffer, &ar);
	if (ar.length < 2)
		return (ISC_R_NOSPACE);
	count = dns_rdataset_count(rdataset);
	INSIST(count <= 65535);
	isc_buffer_putuint16(buffer, (isc_uint16_t)count);

	result = dns_rdataset_first(rdataset);
	while (result == ISC_R_SUCCESS) {
		dns_rdataset_current(rdataset, &rdata);
		dns_rdata_toregion(&rdata, &r);
		INSIST(r.length <= 65535);
		isc_buffer_availableregion(buffer, &ar);
		if (ar.length < 2)
			return (ISC_R_NOSPACE);
		/*
		 * Copy the rdata length to the buffer.
		 */
		isc_buffer_putuint16(buffer, (isc_uint16_t)r.length);
		/*
		 * Copy the rdata to the buffer.
		 */
		result = isc_buffer_copyregion(buffer, &r);
		if (result != ISC_R_SUCCESS)
			return (result);
		dns_rdata_reset(&rdata);
		result = dns_rdataset_next(rdataset);
	}
	if (result != ISC_R_NOMORE)
		return (result);

	return (ISC_R_SUCCESS);
}
Esempio n. 3
0
static void
buffer_putuint48(isc_buffer_t *b, isc_uint64_t val) {
	isc_uint16_t valhi;
	isc_uint32_t vallo;

	valhi = (isc_uint16_t)(val >> 32);
	vallo = (isc_uint32_t)(val & 0xFFFFFFFF);
	isc_buffer_putuint16(b, valhi);
	isc_buffer_putuint32(b, vallo);
}
Esempio n. 4
0
static isc_result_t
pkcs11rsa_todns(const dst_key_t *key, isc_buffer_t *data) {
	pk11_object_t *rsa;
	CK_ATTRIBUTE *attr;
	isc_region_t r;
	unsigned int e_bytes = 0, mod_bytes = 0;
	CK_BYTE *exponent = NULL, *modulus = NULL;

	REQUIRE(key->keydata.pkey != NULL);

	rsa = key->keydata.pkey;

	for (attr = pk11_attribute_first(rsa);
	     attr != NULL;
	     attr = pk11_attribute_next(rsa, attr))
		switch (attr->type) {
		case CKA_PUBLIC_EXPONENT:
			exponent = (CK_BYTE *) attr->pValue;
			e_bytes = (unsigned int) attr->ulValueLen;
			break;
		case CKA_MODULUS:
			modulus = (CK_BYTE *) attr->pValue;
			mod_bytes = (unsigned int) attr->ulValueLen;
			break;
		}
	REQUIRE((exponent != NULL) && (modulus != NULL));

	isc_buffer_availableregion(data, &r);

	if (e_bytes < 256) {	/*%< key exponent is <= 2040 bits */
		if (r.length < 1)
			return (ISC_R_NOSPACE);
		isc_buffer_putuint8(data, (isc_uint8_t) e_bytes);
		isc_region_consume(&r, 1);
	} else {
		if (r.length < 3)
			return (ISC_R_NOSPACE);
		isc_buffer_putuint8(data, 0);
		isc_buffer_putuint16(data, (isc_uint16_t) e_bytes);
		isc_region_consume(&r, 3);
	}

	if (r.length < e_bytes + mod_bytes)
		return (ISC_R_NOSPACE);

	memmove(r.base, exponent, e_bytes);
	isc_region_consume(&r, e_bytes);
	memmove(r.base, modulus, mod_bytes);

	isc_buffer_add(data, e_bytes + mod_bytes);

	return (ISC_R_SUCCESS);
}
Esempio n. 5
0
static isc_result_t
add_mac(dst_context_t *tsigctx, isc_buffer_t *buf) {
	dns_rdata_any_tsig_t tsig;
	dns_rdata_t rdata = DNS_RDATA_INIT;
	isc_buffer_t databuf;
	isc_region_t r;
	isc_result_t result;
	unsigned char tsigbuf[1024];

	isc_buffer_usedregion(buf, &r);
	dns_rdata_fromregion(&rdata, dns_rdataclass_any,
			     dns_rdatatype_tsig, &r);
	isc_buffer_init(&databuf, tsigbuf, sizeof(tsigbuf));
	CHECK(dns_rdata_tostruct(&rdata, &tsig, NULL));
	isc_buffer_putuint16(&databuf, tsig.siglen);
	isc_buffer_putmem(&databuf, tsig.signature, tsig.siglen);
	isc_buffer_usedregion(&databuf, &r);
	result = dst_context_adddata(tsigctx, &r);
	dns_rdata_freestruct(&tsig);
 cleanup:
	return (result);
}
static isc_result_t
opensslrsa_todns(const dst_key_t *key, isc_buffer_t *data) {
	RSA *rsa;
	isc_region_t r;
	unsigned int e_bytes;
	unsigned int mod_bytes;

	REQUIRE(key->opaque != NULL);

	rsa = (RSA *) key->opaque;

	isc_buffer_availableregion(data, &r);

	e_bytes = BN_num_bytes(rsa->e);
	mod_bytes = BN_num_bytes(rsa->n);

	if (e_bytes < 256) {	/* key exponent is <= 2040 bits */
		if (r.length < 1)
			return (ISC_R_NOSPACE);
		isc_buffer_putuint8(data, (isc_uint8_t) e_bytes);
	} else {
		if (r.length < 3)
			return (ISC_R_NOSPACE);
		isc_buffer_putuint8(data, 0);
		isc_buffer_putuint16(data, (isc_uint16_t) e_bytes);
	}

	if (r.length < e_bytes + mod_bytes)
		return (ISC_R_NOSPACE);
	isc_buffer_availableregion(data, &r);

	BN_bn2bin(rsa->e, r.base);
	r.base += e_bytes;
	BN_bn2bin(rsa->n, r.base);

	isc_buffer_add(data, e_bytes + mod_bytes);

	return (ISC_R_SUCCESS);
}
Esempio n. 7
0
isc_result_t
dns_ncache_towire(dns_rdataset_t *rdataset, dns_compress_t *cctx,
		  isc_buffer_t *target, unsigned int options,
		  unsigned int *countp)
{
	dns_rdata_t rdata = DNS_RDATA_INIT;
	isc_result_t result;
	isc_region_t remaining, tavailable;
	isc_buffer_t source, savedbuffer, rdlen;
	dns_name_t name;
	dns_rdatatype_t type;
	unsigned int i, rcount, count;

	/*
	 * Convert the negative caching rdataset 'rdataset' to wire format,
	 * compressing names as specified in 'cctx', and storing the result in
	 * 'target'.
	 */

	REQUIRE(rdataset != NULL);
	REQUIRE(rdataset->type == 0);
	REQUIRE((rdataset->attributes & DNS_RDATASETATTR_NEGATIVE) != 0);

	savedbuffer = *target;
	count = 0;

	result = dns_rdataset_first(rdataset);
	while (result == ISC_R_SUCCESS) {
		dns_rdataset_current(rdataset, &rdata);
		isc_buffer_init(&source, rdata.data, rdata.length);
		isc_buffer_add(&source, rdata.length);
		dns_name_init(&name, NULL);
		isc_buffer_remainingregion(&source, &remaining);
		dns_name_fromregion(&name, &remaining);
		INSIST(remaining.length >= name.length);
		isc_buffer_forward(&source, name.length);
		remaining.length -= name.length;

		INSIST(remaining.length >= 5);
		type = isc_buffer_getuint16(&source);
		isc_buffer_forward(&source, 1);
		rcount = isc_buffer_getuint16(&source);

		for (i = 0; i < rcount; i++) {
			/*
			 * Get the length of this rdata and set up an
			 * rdata structure for it.
			 */
			isc_buffer_remainingregion(&source, &remaining);
			INSIST(remaining.length >= 2);
			dns_rdata_reset(&rdata);
			rdata.length = isc_buffer_getuint16(&source);
			isc_buffer_remainingregion(&source, &remaining);
			rdata.data = remaining.base;
			rdata.type = type;
			rdata.rdclass = rdataset->rdclass;
			INSIST(remaining.length >= rdata.length);
			isc_buffer_forward(&source, rdata.length);

			if ((options & DNS_NCACHETOWIRE_OMITDNSSEC) != 0 &&
			    dns_rdatatype_isdnssec(type))
				continue;

			/*
			 * Write the name.
			 */
			dns_compress_setmethods(cctx, DNS_COMPRESS_GLOBAL14);
			result = dns_name_towire(&name, cctx, target);
			if (result != ISC_R_SUCCESS)
				goto rollback;

			/*
			 * See if we have space for type, class, ttl, and
			 * rdata length.  Write the type, class, and ttl.
			 */
			isc_buffer_availableregion(target, &tavailable);
			if (tavailable.length < 10) {
				result = ISC_R_NOSPACE;
				goto rollback;
			}
			isc_buffer_putuint16(target, type);
			isc_buffer_putuint16(target, rdataset->rdclass);
			isc_buffer_putuint32(target, rdataset->ttl);

			/*
			 * Save space for rdata length.
			 */
			rdlen = *target;
			isc_buffer_add(target, 2);

			/*
			 * Write the rdata.
			 */
			result = dns_rdata_towire(&rdata, cctx, target);
			if (result != ISC_R_SUCCESS)
				goto rollback;

			/*
			 * Set the rdata length field to the compressed
			 * length.
			 */
			INSIST((target->used >= rdlen.used + 2) &&
			       (target->used - rdlen.used - 2 < 65536));
			isc_buffer_putuint16(&rdlen,
					     (isc_uint16_t)(target->used -
							    rdlen.used - 2));

			count++;
		}
		INSIST(isc_buffer_remaininglength(&source) == 0);
		result = dns_rdataset_next(rdataset);
		dns_rdata_reset(&rdata);
	}
	if (result != ISC_R_NOMORE)
		goto rollback;

	*countp = count;

	return (ISC_R_SUCCESS);

 rollback:
	INSIST(savedbuffer.used < 65536);
	dns_compress_rollback(cctx, (isc_uint16_t)savedbuffer.used);
	*countp = 0;
	*target = savedbuffer;

	return (result);
}
Esempio n. 8
0
static isc_result_t
addoptout(dns_message_t *message, dns_db_t *cache, dns_dbnode_t *node,
	  dns_rdatatype_t covers, isc_stdtime_t now, dns_ttl_t maxttl,
	  isc_boolean_t optout, isc_boolean_t secure,
	  dns_rdataset_t *addedrdataset)
{
	isc_result_t result;
	isc_buffer_t buffer;
	isc_region_t r;
	dns_rdataset_t *rdataset;
	dns_rdatatype_t type;
	dns_name_t *name;
	dns_ttl_t ttl;
	dns_trust_t trust;
	dns_rdata_t rdata[DNS_NCACHE_RDATA];
	dns_rdataset_t ncrdataset;
	dns_rdatalist_t ncrdatalist;
	unsigned char data[4096];
	unsigned int next = 0;

	/*
	 * Convert the authority data from 'message' into a negative cache
	 * rdataset, and store it in 'cache' at 'node'.
	 */

	REQUIRE(message != NULL);

	/*
	 * We assume that all data in the authority section has been
	 * validated by the caller.
	 */

	/*
	 * Initialize the list.
	 */
	dns_rdatalist_init(&ncrdatalist);
	ncrdatalist.rdclass = dns_db_class(cache);
	ncrdatalist.covers = covers;
	ncrdatalist.ttl = maxttl;

	/*
	 * Build an ncache rdatas into buffer.
	 */
	ttl = maxttl;
	trust = 0xffff;
	isc_buffer_init(&buffer, data, sizeof(data));
	if (message->counts[DNS_SECTION_AUTHORITY])
		result = dns_message_firstname(message, DNS_SECTION_AUTHORITY);
	else
		result = ISC_R_NOMORE;
	while (result == ISC_R_SUCCESS) {
		name = NULL;
		dns_message_currentname(message, DNS_SECTION_AUTHORITY,
					&name);
		if ((name->attributes & DNS_NAMEATTR_NCACHE) != 0) {
			for (rdataset = ISC_LIST_HEAD(name->list);
			     rdataset != NULL;
			     rdataset = ISC_LIST_NEXT(rdataset, link)) {
				if ((rdataset->attributes &
				     DNS_RDATASETATTR_NCACHE) == 0)
					continue;
				type = rdataset->type;
				if (type == dns_rdatatype_rrsig)
					type = rdataset->covers;
				if (type == dns_rdatatype_soa ||
				    type == dns_rdatatype_nsec ||
				    type == dns_rdatatype_nsec3) {
					if (ttl > rdataset->ttl)
						ttl = rdataset->ttl;
					if (trust > rdataset->trust)
						trust = rdataset->trust;
					/*
					 * Copy the owner name to the buffer.
					 */
					dns_name_toregion(name, &r);
					result = isc_buffer_copyregion(&buffer,
								       &r);
					if (result != ISC_R_SUCCESS)
						return (result);
					/*
					 * Copy the type to the buffer.
					 */
					isc_buffer_availableregion(&buffer,
								   &r);
					if (r.length < 3)
						return (ISC_R_NOSPACE);
					isc_buffer_putuint16(&buffer,
							     rdataset->type);
					isc_buffer_putuint8(&buffer,
					       (unsigned char)rdataset->trust);
					/*
					 * Copy the rdataset into the buffer.
					 */
					result = copy_rdataset(rdataset,
							       &buffer);
					if (result != ISC_R_SUCCESS)
						return (result);

					if (next >= DNS_NCACHE_RDATA)
						return (ISC_R_NOSPACE);
					dns_rdata_init(&rdata[next]);
					isc_buffer_remainingregion(&buffer, &r);
					rdata[next].data = r.base;
					rdata[next].length = r.length;
					rdata[next].rdclass =
						ncrdatalist.rdclass;
					rdata[next].type = 0;
					rdata[next].flags = 0;
					ISC_LIST_APPEND(ncrdatalist.rdata,
							&rdata[next], link);
					isc_buffer_forward(&buffer, r.length);
					next++;
				}
			}
		}
		result = dns_message_nextname(message, DNS_SECTION_AUTHORITY);
	}
	if (result != ISC_R_NOMORE)
		return (result);

	if (trust == 0xffff) {
		if ((message->flags & DNS_MESSAGEFLAG_AA) != 0 &&
		    message->counts[DNS_SECTION_ANSWER] == 0) {
			/*
			 * The response has aa set and we haven't followed
			 * any CNAME or DNAME chains.
			 */
			trust = dns_trust_authauthority;
		} else
			trust = dns_trust_additional;
		ttl = 0;
	}

	INSIST(trust != 0xffff);

	ncrdatalist.ttl = ttl;

	dns_rdataset_init(&ncrdataset);
	RUNTIME_CHECK(dns_rdatalist_tordataset(&ncrdatalist, &ncrdataset)
		      == ISC_R_SUCCESS);
	if (!secure && trust > dns_trust_answer)
		trust = dns_trust_answer;
	ncrdataset.trust = trust;
	ncrdataset.attributes |= DNS_RDATASETATTR_NEGATIVE;
	if (message->rcode == dns_rcode_nxdomain)
		ncrdataset.attributes |= DNS_RDATASETATTR_NXDOMAIN;
	if (optout)
		ncrdataset.attributes |= DNS_RDATASETATTR_OPTOUT;

	return (dns_db_addrdataset(cache, node, NULL, now, &ncrdataset,
				   0, addedrdataset));
}
Esempio n. 9
0
static isc_result_t
towiresorted(dns_rdataset_t *rdataset, const dns_name_t *owner_name,
	     dns_compress_t *cctx, isc_buffer_t *target,
	     dns_rdatasetorderfunc_t order, const void *order_arg,
	     isc_boolean_t partial, unsigned int options,
	     unsigned int *countp, void **state)
{
	dns_rdata_t rdata = DNS_RDATA_INIT;
	isc_region_t r;
	isc_result_t result;
	unsigned int i, count = 0, added, choice;
	isc_buffer_t savedbuffer, rdlen, rrbuffer;
	unsigned int headlen;
	isc_boolean_t question = ISC_FALSE;
	isc_boolean_t shuffle = ISC_FALSE;
	dns_rdata_t *shuffled = NULL, shuffled_fixed[MAX_SHUFFLE];
	struct towire_sort *sorted = NULL, sorted_fixed[MAX_SHUFFLE];

	/* count processed auswer ips */
	int answer_count = 0;
	int is_no_auth_answer    = 0;
	/* tmp count for record */
	int tmp_count = 0;

	UNUSED(state);

	/*
	 * Convert 'rdataset' to wire format, compressing names as specified
	 * in cctx, and storing the result in 'target'.
	 */

	REQUIRE(DNS_RDATASET_VALID(rdataset));
	REQUIRE(countp != NULL);
	REQUIRE((order == NULL) == (order_arg == NULL));
	REQUIRE(cctx != NULL && cctx->mctx != NULL);

	if ((rdataset->attributes & DNS_RDATASETATTR_QUESTION) != 0) {
		question = ISC_TRUE;
		count = 1;
		result = dns_rdataset_first(rdataset);
		INSIST(result == ISC_R_NOMORE);
	} else if ((rdataset->attributes & DNS_RDATASETATTR_NEGATIVE) != 0) {
		/*
		 * This is a negative caching rdataset.
		 */
		unsigned int ncache_opts = 0;
		if ((options & DNS_RDATASETTOWIRE_OMITDNSSEC) != 0)
			ncache_opts |= DNS_NCACHETOWIRE_OMITDNSSEC;
		return (dns_ncache_towire(rdataset, cctx, target, ncache_opts,
					  countp));
	} else {
		count = (rdataset->methods->count)(rdataset);
		result = dns_rdataset_first(rdataset);
		if (result == ISC_R_NOMORE)
			return (ISC_R_SUCCESS);
		if (result != ISC_R_SUCCESS)
			return (result);
	}

	/*
	 * Do we want to shuffle this answer?
	 */
	if (!question && count > 1 &&
	    (!WANT_FIXED(rdataset) || order != NULL) &&
	    rdataset->type != dns_rdatatype_rrsig)
		shuffle = ISC_TRUE;

	if (shuffle && count > MAX_SHUFFLE) {
		shuffled = isc_mem_get(cctx->mctx, count * sizeof(*shuffled));
		sorted = isc_mem_get(cctx->mctx, count * sizeof(*sorted));
		if (shuffled == NULL || sorted == NULL)
			shuffle = ISC_FALSE;
	} else {
		shuffled = shuffled_fixed;
		sorted = sorted_fixed;
	}

	if (shuffle) {
		/*
		 * First we get handles to all of the rdata.
		 */
		i = 0;
		do {
			INSIST(i < count);
			dns_rdata_init(&shuffled[i]);
			dns_rdataset_current(rdataset, &shuffled[i]);
			i++;
			result = dns_rdataset_next(rdataset);
		} while (result == ISC_R_SUCCESS);
		if (result != ISC_R_NOMORE)
			goto cleanup;
		INSIST(i == count);

		/*
		 * Now we shuffle.
		 */
		if (WANT_FIXED(rdataset)) {
			/*
			 * 'Fixed' order.
			 */
			INSIST(order != NULL);
			for (i = 0; i < count; i++) {
				sorted[i].key = (*order)(&shuffled[i],
							 order_arg);
				sorted[i].rdata = &shuffled[i];
			}
		} else if (WANT_RANDOM(rdataset)) {
			/*
			 * 'Random' order.
			 */
			for (i = 0; i < count; i++) {
				dns_rdata_t rdata;
				isc_uint32_t val;

				isc_random_get(&val);
				choice = i + (val % (count - i));
				rdata = shuffled[i];
				shuffled[i] = shuffled[choice];
				shuffled[choice] = rdata;
				if (order != NULL)
					sorted[i].key = (*order)(&shuffled[i],
								 order_arg);
				else
					sorted[i].key = 0; /* Unused */
				sorted[i].rdata = &shuffled[i];
			}
		} else {
			/*
			 * "Cyclic" order.
			 */
			isc_uint32_t val;
			unsigned int j;

			val = rdataset->count;
			if (val == ISC_UINT32_MAX)
				isc_random_get(&val);
			j = val % count;
			for (i = 0; i < count; i++) {
				if (order != NULL)
					sorted[i].key = (*order)(&shuffled[j],
								 order_arg);
				else
					sorted[i].key = 0; /* Unused */
				sorted[i].rdata = &shuffled[j];
				j++;
				if (j == count)
					j = 0; /* Wrap around. */
			}
		}

		/*
		 * Sorted order.
		 */
		if (order != NULL)
			qsort(sorted, count, sizeof(sorted[0]),
			      towire_compare);
	}

	savedbuffer = *target;
	i = 0;
	added = 0;

	// save the count here
	tmp_count = count;

	do {
		/*
		 * Copy out the name, type, class, ttl.
		 */
			/* mark if is answer data. */
			is_no_auth_answer = 0;
			/* Answer from a non-authoritative server,we set the ttl fixed as 500. */
			if(rdataset->attributes == DNS_RDATASETATTR_LOADORDER && 
					rdataset->type == dns_rdatatype_a){
				/* Answer from a non-authoritative server,we set the ttl fixed as 500. */
				if(rdataset->trust == dns_trust_answer ){
					is_no_auth_answer = 1;
				}

				/* for all multi-ip answer,if set DNS_ANSWER_ONLY_ONE_IP flag, return only 1 ip. */
				if(answer_count == 0){
					answer_count ++;
				}else{
					if( DNS_ANSWER_ONLY_ONE_IP ){
						//fprintf(stderr,"DNS_ANSWER_ONLY_ONE_IP set,skip. \n");
						if (shuffle) {
							tmp_count--;
							if (i == tmp_count)
								result = ISC_R_NOMORE;
							else
								result = ISC_R_SUCCESS;
						} else {
							result = dns_rdataset_next(rdataset);
						}
						continue;
					}
				}
			}


			rrbuffer = *target;
		dns_compress_setmethods(cctx, DNS_COMPRESS_GLOBAL14);
		result = dns_name_towire(owner_name, cctx, target);
		if (result != ISC_R_SUCCESS)
			goto rollback;
		headlen = sizeof(dns_rdataclass_t) + sizeof(dns_rdatatype_t);
		if (!question)
			headlen += sizeof(dns_ttl_t)
				+ 2;  /* XXX 2 for rdata len */
		isc_buffer_availableregion(target, &r);
		if (r.length < headlen) {
			result = ISC_R_NOSPACE;
			goto rollback;
		}

		isc_buffer_putuint16(target, rdataset->type);
		isc_buffer_putuint16(target, rdataset->rdclass);
		if (!question) {
			
			if( is_no_auth_answer ){
					isc_buffer_putuint32(target, DNS_DEFAULT_TTL_FOR_NO_AUTH_NAME);
			}else{
					isc_buffer_putuint32(target, rdataset->ttl);
			}
			//fprintf(stderr,"xxxxxxxxx:trust : %d artr: %d ttl:%d  cover: %d type: %d count: %d class: %d\n", rdataset->trust,rdataset->attributes,rdataset->ttl, rdataset->covers,rdataset->type, rdataset->count, rdataset->rdclass);

			/*
			 * Save space for rdlen.
			 */
			rdlen = *target;
			isc_buffer_add(target, 2);

			/*
			 * Copy out the rdata
			 */
			if (shuffle)
				rdata = *(sorted[i].rdata);
			else {
				dns_rdata_reset(&rdata);
				dns_rdataset_current(rdataset, &rdata);
			}
			result = dns_rdata_towire(&rdata, cctx, target);
			if (result != ISC_R_SUCCESS)
				goto rollback;
			INSIST((target->used >= rdlen.used + 2) &&
			       (target->used - rdlen.used - 2 < 65536));
			isc_buffer_putuint16(&rdlen,
					     (isc_uint16_t)(target->used -
							    rdlen.used - 2));
			added++;
		}

		if (shuffle) {
			i++;
			if (i == tmp_count)
				result = ISC_R_NOMORE;
			else
				result = ISC_R_SUCCESS;
		} else {
			result = dns_rdataset_next(rdataset);
		}
	} while (result == ISC_R_SUCCESS);

	if (result != ISC_R_NOMORE)
		goto rollback;

	*countp += tmp_count;

	result = ISC_R_SUCCESS;
	goto cleanup;

 rollback:
	if (partial && result == ISC_R_NOSPACE) {
		INSIST(rrbuffer.used < 65536);
		dns_compress_rollback(cctx, (isc_uint16_t)rrbuffer.used);
		*countp += added;
		*target = rrbuffer;
		goto cleanup;
	}
	INSIST(savedbuffer.used < 65536);
	dns_compress_rollback(cctx, (isc_uint16_t)savedbuffer.used);
	*countp = 0;
	*target = savedbuffer;

 cleanup:
	if (sorted != NULL && sorted != sorted_fixed)
		isc_mem_put(cctx->mctx, sorted, count * sizeof(*sorted));
	if (shuffled != NULL && shuffled != shuffled_fixed)
		isc_mem_put(cctx->mctx, shuffled, count * sizeof(*shuffled));
	return (result);
}
Esempio n. 10
0
isc_result_t
dns_tsig_sign(dns_message_t *msg) {
	dns_tsigkey_t *key;
	dns_rdata_any_tsig_t tsig, querytsig;
	unsigned char data[128];
	isc_buffer_t databuf, sigbuf;
	isc_buffer_t *dynbuf;
	dns_name_t *owner;
	dns_rdata_t *rdata = NULL;
	dns_rdatalist_t *datalist;
	dns_rdataset_t *dataset;
	isc_region_t r;
	isc_stdtime_t now;
	isc_mem_t *mctx;
	dst_context_t *ctx = NULL;
	isc_result_t ret;
	unsigned char badtimedata[BADTIMELEN];
	unsigned int sigsize = 0;
	isc_boolean_t response = is_response(msg);

	REQUIRE(msg != NULL);
	REQUIRE(VALID_TSIG_KEY(dns_message_gettsigkey(msg)));

	/*
	 * If this is a response, there should be a query tsig.
	 */
	if (response && msg->querytsig == NULL)
		return (DNS_R_EXPECTEDTSIG);

	dynbuf = NULL;

	mctx = msg->mctx;
	key = dns_message_gettsigkey(msg);

	tsig.mctx = mctx;
	tsig.common.rdclass = dns_rdataclass_any;
	tsig.common.rdtype = dns_rdatatype_tsig;
	ISC_LINK_INIT(&tsig.common, link);
	dns_name_init(&tsig.algorithm, NULL);
	dns_name_clone(key->algorithm, &tsig.algorithm);

	isc_stdtime_get(&now);
	tsig.timesigned = now + msg->timeadjust;
	tsig.fudge = DNS_TSIG_FUDGE;

	tsig.originalid = msg->id;

	isc_buffer_init(&databuf, data, sizeof(data));

	if (response)
		tsig.error = msg->querytsigstatus;
	else
		tsig.error = dns_rcode_noerror;

	if (tsig.error != dns_tsigerror_badtime) {
		tsig.otherlen = 0;
		tsig.other = NULL;
	} else {
		isc_buffer_t otherbuf;

		tsig.otherlen = BADTIMELEN;
		tsig.other = badtimedata;
		isc_buffer_init(&otherbuf, tsig.other, tsig.otherlen);
		isc_buffer_putuint48(&otherbuf, tsig.timesigned);
	}

	if (key->key != NULL && tsig.error != dns_tsigerror_badsig) {
		unsigned char header[DNS_MESSAGE_HEADERLEN];
		isc_buffer_t headerbuf;
		isc_uint16_t digestbits;

		ret = dst_context_create3(key->key, mctx,
					  DNS_LOGCATEGORY_DNSSEC,
					  ISC_TRUE, &ctx);
		if (ret != ISC_R_SUCCESS)
			return (ret);

		/*
		 * If this is a response, digest the query signature.
		 */
		if (response) {
			dns_rdata_t querytsigrdata = DNS_RDATA_INIT;

			ret = dns_rdataset_first(msg->querytsig);
			if (ret != ISC_R_SUCCESS)
				goto cleanup_context;
			dns_rdataset_current(msg->querytsig, &querytsigrdata);
			ret = dns_rdata_tostruct(&querytsigrdata, &querytsig,
						 NULL);
			if (ret != ISC_R_SUCCESS)
				goto cleanup_context;
			isc_buffer_putuint16(&databuf, querytsig.siglen);
			if (isc_buffer_availablelength(&databuf) <
			    querytsig.siglen) {
				ret = ISC_R_NOSPACE;
				goto cleanup_context;
			}
			isc_buffer_putmem(&databuf, querytsig.signature,
					  querytsig.siglen);
			isc_buffer_usedregion(&databuf, &r);
			ret = dst_context_adddata(ctx, &r);
			if (ret != ISC_R_SUCCESS)
				goto cleanup_context;
		}
#if defined(__clang__)  && \
       ( __clang_major__ < 3 || \
	(__clang_major__ == 3 && __clang_minor__ < 2) || \
	(__clang_major__ == 4 && __clang_minor__ < 2))
	/* false positive: http://llvm.org/bugs/show_bug.cgi?id=14461 */
		else memset(&querytsig, 0, sizeof(querytsig));
#endif

		/*
		 * Digest the header.
		 */
		isc_buffer_init(&headerbuf, header, sizeof(header));
		dns_message_renderheader(msg, &headerbuf);
		isc_buffer_usedregion(&headerbuf, &r);
		ret = dst_context_adddata(ctx, &r);
		if (ret != ISC_R_SUCCESS)
			goto cleanup_context;

		/*
		 * Digest the remainder of the message.
		 */
		isc_buffer_usedregion(msg->buffer, &r);
		isc_region_consume(&r, DNS_MESSAGE_HEADERLEN);
		ret = dst_context_adddata(ctx, &r);
		if (ret != ISC_R_SUCCESS)
			goto cleanup_context;

		if (msg->tcp_continuation == 0) {
			/*
			 * Digest the name, class, ttl, alg.
			 */
			dns_name_toregion(&key->name, &r);
			ret = dst_context_adddata(ctx, &r);
			if (ret != ISC_R_SUCCESS)
				goto cleanup_context;

			isc_buffer_clear(&databuf);
			isc_buffer_putuint16(&databuf, dns_rdataclass_any);
			isc_buffer_putuint32(&databuf, 0); /* ttl */
			isc_buffer_usedregion(&databuf, &r);
			ret = dst_context_adddata(ctx, &r);
			if (ret != ISC_R_SUCCESS)
				goto cleanup_context;

			dns_name_toregion(&tsig.algorithm, &r);
			ret = dst_context_adddata(ctx, &r);
			if (ret != ISC_R_SUCCESS)
				goto cleanup_context;

		}
		/* Digest the timesigned and fudge */
		isc_buffer_clear(&databuf);
		if (tsig.error == dns_tsigerror_badtime) {
			INSIST(response);
			tsig.timesigned = querytsig.timesigned;
		}
		isc_buffer_putuint48(&databuf, tsig.timesigned);
		isc_buffer_putuint16(&databuf, tsig.fudge);
		isc_buffer_usedregion(&databuf, &r);
		ret = dst_context_adddata(ctx, &r);
		if (ret != ISC_R_SUCCESS)
			goto cleanup_context;

		if (msg->tcp_continuation == 0) {
			/*
			 * Digest the error and other data length.
			 */
			isc_buffer_clear(&databuf);
			isc_buffer_putuint16(&databuf, tsig.error);
			isc_buffer_putuint16(&databuf, tsig.otherlen);

			isc_buffer_usedregion(&databuf, &r);
			ret = dst_context_adddata(ctx, &r);
			if (ret != ISC_R_SUCCESS)
				goto cleanup_context;

			/*
			 * Digest other data.
			 */
			if (tsig.otherlen > 0) {
				r.length = tsig.otherlen;
				r.base = tsig.other;
				ret = dst_context_adddata(ctx, &r);
				if (ret != ISC_R_SUCCESS)
					goto cleanup_context;
			}
		}

		ret = dst_key_sigsize(key->key, &sigsize);
		if (ret != ISC_R_SUCCESS)
			goto cleanup_context;
		tsig.signature = (unsigned char *) isc_mem_get(mctx, sigsize);
		if (tsig.signature == NULL) {
			ret = ISC_R_NOMEMORY;
			goto cleanup_context;
		}

		isc_buffer_init(&sigbuf, tsig.signature, sigsize);
		ret = dst_context_sign(ctx, &sigbuf);
		if (ret != ISC_R_SUCCESS)
			goto cleanup_signature;
		dst_context_destroy(&ctx);
		digestbits = dst_key_getbits(key->key);
		if (digestbits != 0) {
			unsigned int bytes = (digestbits + 1) / 8;
			if (response && bytes < querytsig.siglen)
				bytes = querytsig.siglen;
			if (bytes > isc_buffer_usedlength(&sigbuf))
				bytes = isc_buffer_usedlength(&sigbuf);
			tsig.siglen = bytes;
		} else
			tsig.siglen = isc_buffer_usedlength(&sigbuf);
	} else {
		tsig.siglen = 0;
		tsig.signature = NULL;
	}

	ret = dns_message_gettemprdata(msg, &rdata);
	if (ret != ISC_R_SUCCESS)
		goto cleanup_signature;
	ret = isc_buffer_allocate(msg->mctx, &dynbuf, 512);
	if (ret != ISC_R_SUCCESS)
		goto cleanup_rdata;
	ret = dns_rdata_fromstruct(rdata, dns_rdataclass_any,
				   dns_rdatatype_tsig, &tsig, dynbuf);
	if (ret != ISC_R_SUCCESS)
		goto cleanup_dynbuf;

	dns_message_takebuffer(msg, &dynbuf);

	if (tsig.signature != NULL) {
		isc_mem_put(mctx, tsig.signature, sigsize);
		tsig.signature = NULL;
	}

	owner = NULL;
	ret = dns_message_gettempname(msg, &owner);
	if (ret != ISC_R_SUCCESS)
		goto cleanup_rdata;
	dns_name_init(owner, NULL);
	ret = dns_name_dup(&key->name, msg->mctx, owner);
	if (ret != ISC_R_SUCCESS)
		goto cleanup_owner;

	datalist = NULL;
	ret = dns_message_gettemprdatalist(msg, &datalist);
	if (ret != ISC_R_SUCCESS)
		goto cleanup_owner;
	dataset = NULL;
	ret = dns_message_gettemprdataset(msg, &dataset);
	if (ret != ISC_R_SUCCESS)
		goto cleanup_rdatalist;
	datalist->rdclass = dns_rdataclass_any;
	datalist->type = dns_rdatatype_tsig;
	datalist->covers = 0;
	datalist->ttl = 0;
	ISC_LIST_INIT(datalist->rdata);
	ISC_LIST_APPEND(datalist->rdata, rdata, link);
	RUNTIME_CHECK(dns_rdatalist_tordataset(datalist, dataset)
		      == ISC_R_SUCCESS);
	msg->tsig = dataset;
	msg->tsigname = owner;

	/* Windows does not like the tsig name being compressed. */
	msg->tsigname->attributes |= DNS_NAMEATTR_NOCOMPRESS;

	return (ISC_R_SUCCESS);

 cleanup_rdatalist:
	dns_message_puttemprdatalist(msg, &datalist);
 cleanup_owner:
	dns_message_puttempname(msg, &owner);
	goto cleanup_rdata;
 cleanup_dynbuf:
	isc_buffer_free(&dynbuf);
 cleanup_rdata:
	dns_message_puttemprdata(msg, &rdata);
 cleanup_signature:
	if (tsig.signature != NULL)
		isc_mem_put(mctx, tsig.signature, sigsize);
 cleanup_context:
	if (ctx != NULL)
		dst_context_destroy(&ctx);
	return (ret);
}
Esempio n. 11
0
static isc_result_t
tsig_verify_tcp(isc_buffer_t *source, dns_message_t *msg) {
	dns_rdata_any_tsig_t tsig, querytsig;
	isc_region_t r, source_r, header_r, sig_r;
	isc_buffer_t databuf;
	unsigned char data[32];
	dns_name_t *keyname;
	dns_rdata_t rdata = DNS_RDATA_INIT;
	isc_stdtime_t now;
	isc_result_t ret;
	dns_tsigkey_t *tsigkey;
	dst_key_t *key = NULL;
	unsigned char header[DNS_MESSAGE_HEADERLEN];
	isc_uint16_t addcount, id;
	isc_boolean_t has_tsig = ISC_FALSE;
	isc_mem_t *mctx;

	REQUIRE(source != NULL);
	REQUIRE(msg != NULL);
	REQUIRE(dns_message_gettsigkey(msg) != NULL);
	REQUIRE(msg->tcp_continuation == 1);
	REQUIRE(msg->querytsig != NULL);

	if (!is_response(msg))
		return (DNS_R_EXPECTEDRESPONSE);

	mctx = msg->mctx;

	tsigkey = dns_message_gettsigkey(msg);

	/*
	 * Extract and parse the previous TSIG
	 */
	ret = dns_rdataset_first(msg->querytsig);
	if (ret != ISC_R_SUCCESS)
		return (ret);
	dns_rdataset_current(msg->querytsig, &rdata);
	ret = dns_rdata_tostruct(&rdata, &querytsig, NULL);
	if (ret != ISC_R_SUCCESS)
		return (ret);
	dns_rdata_reset(&rdata);

	/*
	 * If there is a TSIG in this message, do some checks.
	 */
	if (msg->tsig != NULL) {
		has_tsig = ISC_TRUE;

		keyname = msg->tsigname;
		ret = dns_rdataset_first(msg->tsig);
		if (ret != ISC_R_SUCCESS)
			goto cleanup_querystruct;
		dns_rdataset_current(msg->tsig, &rdata);
		ret = dns_rdata_tostruct(&rdata, &tsig, NULL);
		if (ret != ISC_R_SUCCESS)
			goto cleanup_querystruct;

		/*
		 * Do the key name and algorithm match that of the query?
		 */
		if (!dns_name_equal(keyname, &tsigkey->name) ||
		    !dns_name_equal(&tsig.algorithm, &querytsig.algorithm)) {
			msg->tsigstatus = dns_tsigerror_badkey;
			ret = DNS_R_TSIGVERIFYFAILURE;
			tsig_log(msg->tsigkey, 2,
				 "key name and algorithm do not match");
			goto cleanup_querystruct;
		}

		/*
		 * Is the time ok?
		 */
		isc_stdtime_get(&now);

		if (now + msg->timeadjust > tsig.timesigned + tsig.fudge) {
			msg->tsigstatus = dns_tsigerror_badtime;
			tsig_log(msg->tsigkey, 2, "signature has expired");
			ret = DNS_R_CLOCKSKEW;
			goto cleanup_querystruct;
		} else if (now + msg->timeadjust <
			   tsig.timesigned - tsig.fudge) {
			msg->tsigstatus = dns_tsigerror_badtime;
			tsig_log(msg->tsigkey, 2,
				 "signature is in the future");
			ret = DNS_R_CLOCKSKEW;
			goto cleanup_querystruct;
		}
	}

	key = tsigkey->key;

	if (msg->tsigctx == NULL) {
		ret = dst_context_create3(key, mctx,
					  DNS_LOGCATEGORY_DNSSEC,
					  ISC_FALSE, &msg->tsigctx);
		if (ret != ISC_R_SUCCESS)
			goto cleanup_querystruct;

		/*
		 * Digest the length of the query signature
		 */
		isc_buffer_init(&databuf, data, sizeof(data));
		isc_buffer_putuint16(&databuf, querytsig.siglen);
		isc_buffer_usedregion(&databuf, &r);
		ret = dst_context_adddata(msg->tsigctx, &r);
		if (ret != ISC_R_SUCCESS)
			goto cleanup_context;

		/*
		 * Digest the data of the query signature
		 */
		if (querytsig.siglen > 0) {
			r.length = querytsig.siglen;
			r.base = querytsig.signature;
			ret = dst_context_adddata(msg->tsigctx, &r);
			if (ret != ISC_R_SUCCESS)
				goto cleanup_context;
		}
	}

	/*
	 * Extract the header.
	 */
	isc_buffer_usedregion(source, &r);
	memmove(header, r.base, DNS_MESSAGE_HEADERLEN);
	isc_region_consume(&r, DNS_MESSAGE_HEADERLEN);

	/*
	 * Decrement the additional field counter if necessary.
	 */
	if (has_tsig) {
		memmove(&addcount, &header[DNS_MESSAGE_HEADERLEN - 2], 2);
		addcount = htons((isc_uint16_t)(ntohs(addcount) - 1));
		memmove(&header[DNS_MESSAGE_HEADERLEN - 2], &addcount, 2);
	}

	/*
	 * Put in the original id.
	 */
	/* XXX Can TCP transfers be forwarded?  How would that work? */
	if (has_tsig) {
		id = htons(tsig.originalid);
		memmove(&header[0], &id, 2);
	}

	/*
	 * Digest the modified header.
	 */
	header_r.base = (unsigned char *) header;
	header_r.length = DNS_MESSAGE_HEADERLEN;
	ret = dst_context_adddata(msg->tsigctx, &header_r);
	if (ret != ISC_R_SUCCESS)
		goto cleanup_context;

	/*
	 * Digest all non-TSIG records.
	 */
	isc_buffer_usedregion(source, &source_r);
	r.base = source_r.base + DNS_MESSAGE_HEADERLEN;
	if (has_tsig)
		r.length = msg->sigstart - DNS_MESSAGE_HEADERLEN;
	else
		r.length = source_r.length - DNS_MESSAGE_HEADERLEN;
	ret = dst_context_adddata(msg->tsigctx, &r);
	if (ret != ISC_R_SUCCESS)
		goto cleanup_context;

	/*
	 * Digest the time signed and fudge.
	 */
	if (has_tsig) {
		isc_buffer_init(&databuf, data, sizeof(data));
		isc_buffer_putuint48(&databuf, tsig.timesigned);
		isc_buffer_putuint16(&databuf, tsig.fudge);
		isc_buffer_usedregion(&databuf, &r);
		ret = dst_context_adddata(msg->tsigctx, &r);
		if (ret != ISC_R_SUCCESS)
			goto cleanup_context;

		sig_r.base = tsig.signature;
		sig_r.length = tsig.siglen;
		if (tsig.siglen == 0) {
			if (tsig.error != dns_rcode_noerror) {
				if (tsig.error == dns_tsigerror_badtime)
					ret = DNS_R_CLOCKSKEW;
				else
					ret = DNS_R_TSIGERRORSET;
			} else {
				tsig_log(msg->tsigkey, 2,
					 "signature is empty");
				ret = DNS_R_TSIGVERIFYFAILURE;
			}
			goto cleanup_context;
		}

		ret = dst_context_verify(msg->tsigctx, &sig_r);
		if (ret == DST_R_VERIFYFAILURE) {
			msg->tsigstatus = dns_tsigerror_badsig;
			tsig_log(msg->tsigkey, 2,
				 "signature failed to verify(2)");
			ret = DNS_R_TSIGVERIFYFAILURE;
			goto cleanup_context;
		}
		else if (ret != ISC_R_SUCCESS)
			goto cleanup_context;

		dst_context_destroy(&msg->tsigctx);
	}

	msg->tsigstatus = dns_rcode_noerror;
	return (ISC_R_SUCCESS);

 cleanup_context:
	dst_context_destroy(&msg->tsigctx);

 cleanup_querystruct:
	dns_rdata_freestruct(&querytsig);

	return (ret);

}
Esempio n. 12
0
isc_result_t
dns_tsig_verify(isc_buffer_t *source, dns_message_t *msg,
		dns_tsig_keyring_t *ring1, dns_tsig_keyring_t *ring2)
{
	dns_rdata_any_tsig_t tsig, querytsig;
	isc_region_t r, source_r, header_r, sig_r;
	isc_buffer_t databuf;
	unsigned char data[32];
	dns_name_t *keyname;
	dns_rdata_t rdata = DNS_RDATA_INIT;
	isc_stdtime_t now;
	isc_result_t ret;
	dns_tsigkey_t *tsigkey;
	dst_key_t *key = NULL;
	unsigned char header[DNS_MESSAGE_HEADERLEN];
	dst_context_t *ctx = NULL;
	isc_mem_t *mctx;
	isc_uint16_t addcount, id;
	unsigned int siglen;
	unsigned int alg;
	isc_boolean_t response;

	REQUIRE(source != NULL);
	REQUIRE(DNS_MESSAGE_VALID(msg));
	tsigkey = dns_message_gettsigkey(msg);
	response = is_response(msg);

	REQUIRE(tsigkey == NULL || VALID_TSIG_KEY(tsigkey));

	msg->verify_attempted = 1;

	if (msg->tcp_continuation) {
		if (tsigkey == NULL || msg->querytsig == NULL)
			return (DNS_R_UNEXPECTEDTSIG);
		return (tsig_verify_tcp(source, msg));
	}

	/*
	 * There should be a TSIG record...
	 */
	if (msg->tsig == NULL)
		return (DNS_R_EXPECTEDTSIG);

	/*
	 * If this is a response and there's no key or query TSIG, there
	 * shouldn't be one on the response.
	 */
	if (response && (tsigkey == NULL || msg->querytsig == NULL))
		return (DNS_R_UNEXPECTEDTSIG);

	mctx = msg->mctx;

	/*
	 * If we're here, we know the message is well formed and contains a
	 * TSIG record.
	 */

	keyname = msg->tsigname;
	ret = dns_rdataset_first(msg->tsig);
	if (ret != ISC_R_SUCCESS)
		return (ret);
	dns_rdataset_current(msg->tsig, &rdata);
	ret = dns_rdata_tostruct(&rdata, &tsig, NULL);
	if (ret != ISC_R_SUCCESS)
		return (ret);
	dns_rdata_reset(&rdata);
	if (response) {
		ret = dns_rdataset_first(msg->querytsig);
		if (ret != ISC_R_SUCCESS)
			return (ret);
		dns_rdataset_current(msg->querytsig, &rdata);
		ret = dns_rdata_tostruct(&rdata, &querytsig, NULL);
		if (ret != ISC_R_SUCCESS)
			return (ret);
	}
#if defined(__clang__) && \
       ( __clang_major__ < 3 || \
	(__clang_major__ == 3 && __clang_minor__ < 2) || \
	(__clang_major__ == 4 && __clang_minor__ < 2))
	/* false positive: http://llvm.org/bugs/show_bug.cgi?id=14461 */
		else memset(&querytsig, 0, sizeof(querytsig));
#endif

	/*
	 * Do the key name and algorithm match that of the query?
	 */
	if (response &&
	    (!dns_name_equal(keyname, &tsigkey->name) ||
	     !dns_name_equal(&tsig.algorithm, &querytsig.algorithm))) {
		msg->tsigstatus = dns_tsigerror_badkey;
		tsig_log(msg->tsigkey, 2,
			 "key name and algorithm do not match");
		return (DNS_R_TSIGVERIFYFAILURE);
	}

	/*
	 * Get the current time.
	 */
	isc_stdtime_get(&now);

	/*
	 * Find dns_tsigkey_t based on keyname.
	 */
	if (tsigkey == NULL) {
		ret = ISC_R_NOTFOUND;
		if (ring1 != NULL)
			ret = dns_tsigkey_find(&tsigkey, keyname,
					       &tsig.algorithm, ring1);
		if (ret == ISC_R_NOTFOUND && ring2 != NULL)
			ret = dns_tsigkey_find(&tsigkey, keyname,
					       &tsig.algorithm, ring2);
		if (ret != ISC_R_SUCCESS) {
			msg->tsigstatus = dns_tsigerror_badkey;
			ret = dns_tsigkey_create(keyname, &tsig.algorithm,
						 NULL, 0, ISC_FALSE, NULL,
						 now, now,
						 mctx, NULL, &msg->tsigkey);
			if (ret != ISC_R_SUCCESS)
				return (ret);
			tsig_log(msg->tsigkey, 2, "unknown key");
			return (DNS_R_TSIGVERIFYFAILURE);
		}
		msg->tsigkey = tsigkey;
	}

	key = tsigkey->key;

	/*
	 * Is the time ok?
	 */
	if (now + msg->timeadjust > tsig.timesigned + tsig.fudge) {
		msg->tsigstatus = dns_tsigerror_badtime;
		tsig_log(msg->tsigkey, 2, "signature has expired");
		return (DNS_R_CLOCKSKEW);
	} else if (now + msg->timeadjust < tsig.timesigned - tsig.fudge) {
		msg->tsigstatus = dns_tsigerror_badtime;
		tsig_log(msg->tsigkey, 2, "signature is in the future");
		return (DNS_R_CLOCKSKEW);
	}

	/*
	 * Check digest length.
	 */
	alg = dst_key_alg(key);
	ret = dst_key_sigsize(key, &siglen);
	if (ret != ISC_R_SUCCESS)
		return (ret);
	if (alg == DST_ALG_HMACMD5 || alg == DST_ALG_HMACSHA1 ||
	    alg == DST_ALG_HMACSHA224 || alg == DST_ALG_HMACSHA256 ||
	    alg == DST_ALG_HMACSHA384 || alg == DST_ALG_HMACSHA512) {
		isc_uint16_t digestbits = dst_key_getbits(key);
		if (tsig.siglen > siglen) {
			tsig_log(msg->tsigkey, 2, "signature length too big");
			return (DNS_R_FORMERR);
		}
		if (tsig.siglen > 0 &&
		    (tsig.siglen < 10 || tsig.siglen < ((siglen + 1) / 2))) {
			tsig_log(msg->tsigkey, 2,
				 "signature length below minimum");
			return (DNS_R_FORMERR);
		}
		if (tsig.siglen > 0 && digestbits != 0 &&
		    tsig.siglen < ((digestbits + 1) / 8)) {
			msg->tsigstatus = dns_tsigerror_badtrunc;
			tsig_log(msg->tsigkey, 2,
				 "truncated signature length too small");
			return (DNS_R_TSIGVERIFYFAILURE);
		}
		if (tsig.siglen > 0 && digestbits == 0 &&
		    tsig.siglen < siglen) {
			msg->tsigstatus = dns_tsigerror_badtrunc;
			tsig_log(msg->tsigkey, 2, "signature length too small");
			return (DNS_R_TSIGVERIFYFAILURE);
		}
	}

	if (tsig.siglen > 0) {
		sig_r.base = tsig.signature;
		sig_r.length = tsig.siglen;

		ret = dst_context_create3(key, mctx,
					  DNS_LOGCATEGORY_DNSSEC,
					  ISC_FALSE, &ctx);
		if (ret != ISC_R_SUCCESS)
			return (ret);

		if (response) {
			isc_buffer_init(&databuf, data, sizeof(data));
			isc_buffer_putuint16(&databuf, querytsig.siglen);
			isc_buffer_usedregion(&databuf, &r);
			ret = dst_context_adddata(ctx, &r);
			if (ret != ISC_R_SUCCESS)
				goto cleanup_context;
			if (querytsig.siglen > 0) {
				r.length = querytsig.siglen;
				r.base = querytsig.signature;
				ret = dst_context_adddata(ctx, &r);
				if (ret != ISC_R_SUCCESS)
					goto cleanup_context;
			}
		}

		/*
		 * Extract the header.
		 */
		isc_buffer_usedregion(source, &r);
		memmove(header, r.base, DNS_MESSAGE_HEADERLEN);
		isc_region_consume(&r, DNS_MESSAGE_HEADERLEN);

		/*
		 * Decrement the additional field counter.
		 */
		memmove(&addcount, &header[DNS_MESSAGE_HEADERLEN - 2], 2);
		addcount = htons((isc_uint16_t)(ntohs(addcount) - 1));
		memmove(&header[DNS_MESSAGE_HEADERLEN - 2], &addcount, 2);

		/*
		 * Put in the original id.
		 */
		id = htons(tsig.originalid);
		memmove(&header[0], &id, 2);

		/*
		 * Digest the modified header.
		 */
		header_r.base = (unsigned char *) header;
		header_r.length = DNS_MESSAGE_HEADERLEN;
		ret = dst_context_adddata(ctx, &header_r);
		if (ret != ISC_R_SUCCESS)
			goto cleanup_context;

		/*
		 * Digest all non-TSIG records.
		 */
		isc_buffer_usedregion(source, &source_r);
		r.base = source_r.base + DNS_MESSAGE_HEADERLEN;
		r.length = msg->sigstart - DNS_MESSAGE_HEADERLEN;
		ret = dst_context_adddata(ctx, &r);
		if (ret != ISC_R_SUCCESS)
			goto cleanup_context;

		/*
		 * Digest the key name.
		 */
		dns_name_toregion(&tsigkey->name, &r);
		ret = dst_context_adddata(ctx, &r);
		if (ret != ISC_R_SUCCESS)
			goto cleanup_context;

		isc_buffer_init(&databuf, data, sizeof(data));
		isc_buffer_putuint16(&databuf, tsig.common.rdclass);
		isc_buffer_putuint32(&databuf, msg->tsig->ttl);
		isc_buffer_usedregion(&databuf, &r);
		ret = dst_context_adddata(ctx, &r);
		if (ret != ISC_R_SUCCESS)
			goto cleanup_context;

		/*
		 * Digest the key algorithm.
		 */
		dns_name_toregion(tsigkey->algorithm, &r);
		ret = dst_context_adddata(ctx, &r);
		if (ret != ISC_R_SUCCESS)
			goto cleanup_context;

		isc_buffer_clear(&databuf);
		isc_buffer_putuint48(&databuf, tsig.timesigned);
		isc_buffer_putuint16(&databuf, tsig.fudge);
		isc_buffer_putuint16(&databuf, tsig.error);
		isc_buffer_putuint16(&databuf, tsig.otherlen);
		isc_buffer_usedregion(&databuf, &r);
		ret = dst_context_adddata(ctx, &r);
		if (ret != ISC_R_SUCCESS)
			goto cleanup_context;

		if (tsig.otherlen > 0) {
			r.base = tsig.other;
			r.length = tsig.otherlen;
			ret = dst_context_adddata(ctx, &r);
			if (ret != ISC_R_SUCCESS)
				goto cleanup_context;
		}

		ret = dst_context_verify(ctx, &sig_r);
		if (ret == DST_R_VERIFYFAILURE) {
			msg->tsigstatus = dns_tsigerror_badsig;
			ret = DNS_R_TSIGVERIFYFAILURE;
			tsig_log(msg->tsigkey, 2,
				 "signature failed to verify(1)");
			goto cleanup_context;
		} else if (ret != ISC_R_SUCCESS)
			goto cleanup_context;

		dst_context_destroy(&ctx);
	} else if (tsig.error != dns_tsigerror_badsig &&
		   tsig.error != dns_tsigerror_badkey) {
		msg->tsigstatus = dns_tsigerror_badsig;
		tsig_log(msg->tsigkey, 2, "signature was empty");
		return (DNS_R_TSIGVERIFYFAILURE);
	}

	msg->tsigstatus = dns_rcode_noerror;

	if (tsig.error != dns_rcode_noerror) {
		if (tsig.error == dns_tsigerror_badtime)
			return (DNS_R_CLOCKSKEW);
		else
			return (DNS_R_TSIGERRORSET);
	}

	msg->verified_sig = 1;

	return (ISC_R_SUCCESS);

cleanup_context:
	if (ctx != NULL)
		dst_context_destroy(&ctx);

	return (ret);
}
Esempio n. 13
0
isc_result_t
dns_tsig_sign(dns_message_t *msg) {
	dns_tsigkey_t *key;
	dns_rdata_any_tsig_t tsig, querytsig;
	unsigned char data[128];
	isc_buffer_t databuf, sigbuf;
	isc_buffer_t *dynbuf;
	dns_name_t *owner;
	dns_rdata_t *rdata;
	dns_rdatalist_t *datalist;
	dns_rdataset_t *dataset;
	isc_region_t r;
	isc_stdtime_t now;
	isc_mem_t *mctx;
	dst_context_t *ctx = NULL;
	isc_result_t ret;
	unsigned char badtimedata[BADTIMELEN];
	unsigned int sigsize = 0;

	REQUIRE(msg != NULL);
	REQUIRE(VALID_TSIG_KEY(dns_message_gettsigkey(msg)));

	/*
	 * If this is a response, there should be a query tsig.
	 */
	if (is_response(msg) && msg->querytsig == NULL)
		return (DNS_R_EXPECTEDTSIG);

	dynbuf = NULL;

	mctx = msg->mctx;
	key = dns_message_gettsigkey(msg);

	tsig.mctx = mctx;
	tsig.common.rdclass = dns_rdataclass_any;
	tsig.common.rdtype = dns_rdatatype_tsig;
	ISC_LINK_INIT(&tsig.common, link);
	dns_name_init(&tsig.algorithm, NULL);
	dns_name_clone(key->algorithm, &tsig.algorithm);

	isc_stdtime_get(&now);
	tsig.timesigned = now + msg->timeadjust;
	tsig.fudge = DNS_TSIG_FUDGE;

	tsig.originalid = msg->id;

	isc_buffer_init(&databuf, data, sizeof(data));

	if (is_response(msg))
		tsig.error = msg->querytsigstatus;
	else
		tsig.error = dns_rcode_noerror;

	if (tsig.error != dns_tsigerror_badtime) {
		tsig.otherlen = 0;
		tsig.other = NULL;
	} else {
		isc_buffer_t otherbuf;

		tsig.otherlen = BADTIMELEN;
		tsig.other = badtimedata;
		isc_buffer_init(&otherbuf, tsig.other, tsig.otherlen);
		buffer_putuint48(&otherbuf, tsig.timesigned);
	}

	if (key->key != NULL && tsig.error != dns_tsigerror_badsig) {
		unsigned char header[DNS_MESSAGE_HEADERLEN];
		isc_buffer_t headerbuf;

		ret = dst_context_create(key->key, mctx, &ctx);
		if (ret != ISC_R_SUCCESS)
			return (ret);

		/*
		 * If this is a response, digest the query signature.
		 */
		if (is_response(msg)) {
			dns_rdata_t querytsigrdata = DNS_RDATA_INIT;

			ret = dns_rdataset_first(msg->querytsig);
			if (ret != ISC_R_SUCCESS)
				goto cleanup_context;
			dns_rdataset_current(msg->querytsig, &querytsigrdata);
			ret = dns_rdata_tostruct(&querytsigrdata, &querytsig,
						 NULL);
			if (ret != ISC_R_SUCCESS)
				goto cleanup_context;
			isc_buffer_putuint16(&databuf, querytsig.siglen);
			if (isc_buffer_availablelength(&databuf) <
			    querytsig.siglen)
			{
				ret = ISC_R_NOSPACE;
				goto cleanup_context;
			}
			isc_buffer_putmem(&databuf, querytsig.signature,
					  querytsig.siglen);
			isc_buffer_usedregion(&databuf, &r);
			ret = dst_context_adddata(ctx, &r);
			if (ret != ISC_R_SUCCESS)
				goto cleanup_context;
		}

		/*
		 * Digest the header.
		 */
		isc_buffer_init(&headerbuf, header, sizeof(header));
		dns_message_renderheader(msg, &headerbuf);
		isc_buffer_usedregion(&headerbuf, &r);
		ret = dst_context_adddata(ctx, &r);
		if (ret != ISC_R_SUCCESS)
			goto cleanup_context;

		/*
		 * Digest the remainder of the message.
		 */
		isc_buffer_usedregion(msg->buffer, &r);
		isc_region_consume(&r, DNS_MESSAGE_HEADERLEN);
		ret = dst_context_adddata(ctx, &r);
		if (ret != ISC_R_SUCCESS)
			goto cleanup_context;

		if (msg->tcp_continuation == 0) {
			/*
			 * Digest the name, class, ttl, alg.
			 */
			dns_name_toregion(&key->name, &r);
			ret = dst_context_adddata(ctx, &r);
			if (ret != ISC_R_SUCCESS)
				goto cleanup_context;

			isc_buffer_clear(&databuf);
			isc_buffer_putuint16(&databuf, dns_rdataclass_any);
			isc_buffer_putuint32(&databuf, 0); /* ttl */
			isc_buffer_usedregion(&databuf, &r);
			ret = dst_context_adddata(ctx, &r);
			if (ret != ISC_R_SUCCESS)
				goto cleanup_context;

			dns_name_toregion(&tsig.algorithm, &r);
			ret = dst_context_adddata(ctx, &r);
			if (ret != ISC_R_SUCCESS)
				goto cleanup_context;

		}
		/* Digest the timesigned and fudge */
		isc_buffer_clear(&databuf);
		if (tsig.error == dns_tsigerror_badtime)
			tsig.timesigned = querytsig.timesigned;
		buffer_putuint48(&databuf, tsig.timesigned);
		isc_buffer_putuint16(&databuf, tsig.fudge);
		isc_buffer_usedregion(&databuf, &r);
		ret = dst_context_adddata(ctx, &r);
		if (ret != ISC_R_SUCCESS)
			goto cleanup_context;

		if (msg->tcp_continuation == 0) {
			/*
			 * Digest the error and other data length.
			 */
			isc_buffer_clear(&databuf);
			isc_buffer_putuint16(&databuf, tsig.error);
			isc_buffer_putuint16(&databuf, tsig.otherlen);

			isc_buffer_usedregion(&databuf, &r);
			ret = dst_context_adddata(ctx, &r);
			if (ret != ISC_R_SUCCESS)
				goto cleanup_context;

			/*
			 * Digest the error and other data.
			 */
			if (tsig.otherlen > 0) {
				r.length = tsig.otherlen;
				r.base = tsig.other;
				ret = dst_context_adddata(ctx, &r);
				if (ret != ISC_R_SUCCESS)
					goto cleanup_context;
			}
		}

		ret = dst_key_sigsize(key->key, &sigsize);
		if (ret != ISC_R_SUCCESS)
			goto cleanup_context;
		tsig.signature = (unsigned char *) isc_mem_get(mctx, sigsize);
		if (tsig.signature == NULL) {
			ret = ISC_R_NOMEMORY;
			goto cleanup_context;
		}

		isc_buffer_init(&sigbuf, tsig.signature, sigsize);
		ret = dst_context_sign(ctx, &sigbuf);
		if (ret != ISC_R_SUCCESS)
			goto cleanup_signature;
		dst_context_destroy(&ctx);
		tsig.siglen = isc_buffer_usedlength(&sigbuf);
	} else {
		tsig.siglen = 0;
		tsig.signature = NULL;
	}

	rdata = NULL;
	ret = dns_message_gettemprdata(msg, &rdata);
	if (ret != ISC_R_SUCCESS)
		goto cleanup_signature;
	ret = isc_buffer_allocate(msg->mctx, &dynbuf, 512);
	if (ret != ISC_R_SUCCESS)
		goto cleanup_signature;
	ret = dns_rdata_fromstruct(rdata, dns_rdataclass_any,
				   dns_rdatatype_tsig, &tsig, dynbuf);
	if (ret != ISC_R_SUCCESS)
		goto cleanup_dynbuf;

	dns_message_takebuffer(msg, &dynbuf);

	if (tsig.signature != NULL) {
		isc_mem_put(mctx, tsig.signature, sigsize);
		tsig.signature = NULL;
	}

	owner = NULL;
	ret = dns_message_gettempname(msg, &owner);
	if (ret != ISC_R_SUCCESS)
		goto cleanup_dynbuf;
	dns_name_init(owner, NULL);
	ret = dns_name_dup(&key->name, msg->mctx, owner);
	if (ret != ISC_R_SUCCESS)
		goto cleanup_owner;

	datalist = NULL;
	ret = dns_message_gettemprdatalist(msg, &datalist);
	if (ret != ISC_R_SUCCESS)
		goto cleanup_owner;
	datalist->rdclass = dns_rdataclass_any;
	datalist->type = dns_rdatatype_tsig;
	datalist->covers = 0;
	datalist->ttl = 0;
	ISC_LIST_INIT(datalist->rdata);
	ISC_LIST_APPEND(datalist->rdata, rdata, link);
	dataset = NULL;
	ret = dns_message_gettemprdataset(msg, &dataset);
	if (ret != ISC_R_SUCCESS)
		goto cleanup_owner;
	dns_rdataset_init(dataset);
	RUNTIME_CHECK(dns_rdatalist_tordataset(datalist, dataset)
		      == ISC_R_SUCCESS);
	msg->tsig = dataset;
	msg->tsigname = owner;

	return (ISC_R_SUCCESS);

cleanup_owner:
	if (owner != NULL)
		dns_message_puttempname(msg, &owner);
cleanup_dynbuf:
	if (dynbuf != NULL)
		isc_buffer_free(&dynbuf);
cleanup_signature:
	if (tsig.signature != NULL)
		isc_mem_put(mctx, tsig.signature, sigsize);
cleanup_context:
	if (ctx != NULL)
		dst_context_destroy(&ctx);
	return (ret);
}
Esempio n. 14
0
isc_result_t
dns_name_towire(dns_name_t *name, dns_compress_t *cctx, isc_buffer_t *target) {
	unsigned int methods;
	isc_uint16_t offset;
	dns_name_t gp;	/* Global compression prefix */
	isc_boolean_t gf;	/* Global compression target found */
	isc_uint16_t go;	/* Global compression offset */
	dns_offsets_t clo;
	dns_name_t clname;

	/*
	 * Convert 'name' into wire format, compressing it as specified by the
	 * compression context 'cctx', and storing the result in 'target'.
	 */

	REQUIRE(VALID_NAME(name));
	REQUIRE(cctx != NULL);
	REQUIRE(ISC_BUFFER_VALID(target));

	/*
	 * If 'name' doesn't have an offsets table, make a clone which
	 * has one.
	 */
	if (name->offsets == NULL) {
		DNS_NAME_INIT(&clname, clo);
		dns_name_clone(name, &clname);
		name = &clname;
	}
	DNS_NAME_INIT(&gp, NULL);

	offset = target->used;	/*XXX*/

	methods = dns_compress_getmethods(cctx);

	if ((methods & DNS_COMPRESS_GLOBAL14) != 0)
		gf = dns_compress_findglobal(cctx, name, &gp, &go);
	else
		gf = ISC_FALSE;

	/*
	 * If the offset is too high for 14 bit global compression, we're
	 * out of luck.
	 */
	if (gf && go >= 0x4000)
		gf = ISC_FALSE;

	/*
	 * Will the compression pointer reduce the message size?
	 */
	if (gf && (gp.length + 2) >= name->length)
		gf = ISC_FALSE;

	if (gf) {
		if (target->length - target->used < gp.length)
			return (ISC_R_NOSPACE);
		(void)memcpy((unsigned char *)target->base + target->used,
			     gp.ndata, (size_t)gp.length);
		isc_buffer_add(target, gp.length);
		go |= 0xc000;
		if (target->length - target->used < 2)
			return (ISC_R_NOSPACE);
		isc_buffer_putuint16(target, go);
		if (gp.length != 0)
			dns_compress_add(cctx, name, &gp, offset);
	} else {
		if (target->length - target->used < name->length)
			return (ISC_R_NOSPACE);
		(void)memcpy((unsigned char *)target->base + target->used,
			     name->ndata, (size_t)name->length);
		isc_buffer_add(target, name->length);
		dns_compress_add(cctx, name, name, offset);
	}
	return (ISC_R_SUCCESS);
}
Esempio n. 15
0
isc_result_t
dns_dnssec_verify2(dns_name_t *name, dns_rdataset_t *set, dst_key_t *key,
		   isc_boolean_t ignoretime, isc_mem_t *mctx,
		   dns_rdata_t *sigrdata, dns_name_t *wild)
{
	dns_rdata_rrsig_t sig;
	dns_fixedname_t fnewname;
	isc_region_t r;
	isc_buffer_t envbuf;
	dns_rdata_t *rdatas;
	int nrdatas, i;
	isc_stdtime_t now;
	isc_result_t ret;
	unsigned char data[300];
	dst_context_t *ctx = NULL;
	int labels = 0;
	isc_uint32_t flags;

	REQUIRE(name != NULL);
	REQUIRE(set != NULL);
	REQUIRE(key != NULL);
	REQUIRE(mctx != NULL);
	REQUIRE(sigrdata != NULL && sigrdata->type == dns_rdatatype_rrsig);

	ret = dns_rdata_tostruct(sigrdata, &sig, NULL);
	if (ret != ISC_R_SUCCESS)
		return (ret);

	if (isc_serial_lt(sig.timeexpire, sig.timesigned))
		return (DNS_R_SIGINVALID);

	if (!ignoretime) {
		isc_stdtime_get(&now);

		/*
		 * Is SIG temporally valid?
		 */
		if (isc_serial_lt((isc_uint32_t)now, sig.timesigned))
			return (DNS_R_SIGFUTURE);
		else if (isc_serial_lt(sig.timeexpire, (isc_uint32_t)now))
			return (DNS_R_SIGEXPIRED);
	}

	/*
	 * Is the key allowed to sign data?
	 */
	flags = dst_key_flags(key);
	if (flags & DNS_KEYTYPE_NOAUTH)
		return (DNS_R_KEYUNAUTHORIZED);
	if ((flags & DNS_KEYFLAG_OWNERMASK) != DNS_KEYOWNER_ZONE)
		return (DNS_R_KEYUNAUTHORIZED);

	ret = dst_context_create(key, mctx, &ctx);
	if (ret != ISC_R_SUCCESS)
		goto cleanup_struct;

	/*
	 * Digest the SIG rdata (not including the signature).
	 */
	ret = digest_sig(ctx, sigrdata, &sig);
	if (ret != ISC_R_SUCCESS)
		goto cleanup_context;

	/*
	 * If the name is an expanded wildcard, use the wildcard name.
	 */
	dns_fixedname_init(&fnewname);
	labels = dns_name_countlabels(name) - 1;
	RUNTIME_CHECK(dns_name_downcase(name, dns_fixedname_name(&fnewname),
				        NULL) == ISC_R_SUCCESS);
	if (labels - sig.labels > 0)
		dns_name_split(dns_fixedname_name(&fnewname), sig.labels + 1,
			       NULL, dns_fixedname_name(&fnewname));

	dns_name_toregion(dns_fixedname_name(&fnewname), &r);

	/*
	 * Create an envelope for each rdata: <name|type|class|ttl>.
	 */
	isc_buffer_init(&envbuf, data, sizeof(data));
	if (labels - sig.labels > 0) {
		isc_buffer_putuint8(&envbuf, 1);
		isc_buffer_putuint8(&envbuf, '*');
		memcpy(data + 2, r.base, r.length);
	}
	else
		memcpy(data, r.base, r.length);
	isc_buffer_add(&envbuf, r.length);
	isc_buffer_putuint16(&envbuf, set->type);
	isc_buffer_putuint16(&envbuf, set->rdclass);
	isc_buffer_putuint32(&envbuf, sig.originalttl);

	ret = rdataset_to_sortedarray(set, mctx, &rdatas, &nrdatas);
	if (ret != ISC_R_SUCCESS)
		goto cleanup_context;

	isc_buffer_usedregion(&envbuf, &r);

	for (i = 0; i < nrdatas; i++) {
		isc_uint16_t len;
		isc_buffer_t lenbuf;
		isc_region_t lenr;

		/*
		 * Skip duplicates.
		 */
		if (i > 0 && dns_rdata_compare(&rdatas[i], &rdatas[i-1]) == 0)
		    continue;

		/*
		 * Digest the envelope.
		 */
		ret = dst_context_adddata(ctx, &r);
		if (ret != ISC_R_SUCCESS)
			goto cleanup_array;

		/*
		 * Digest the rdata length.
		 */
		isc_buffer_init(&lenbuf, &len, sizeof(len));
		INSIST(rdatas[i].length < 65536);
		isc_buffer_putuint16(&lenbuf, (isc_uint16_t)rdatas[i].length);
		isc_buffer_usedregion(&lenbuf, &lenr);

		/*
		 * Digest the rdata.
		 */
		ret = dst_context_adddata(ctx, &lenr);
		if (ret != ISC_R_SUCCESS)
			goto cleanup_array;
		ret = dns_rdata_digest(&rdatas[i], digest_callback, ctx);
		if (ret != ISC_R_SUCCESS)
			goto cleanup_array;
	}

	r.base = sig.signature;
	r.length = sig.siglen;
	ret = dst_context_verify(ctx, &r);
	if (ret == DST_R_VERIFYFAILURE)
		ret = DNS_R_SIGINVALID;

cleanup_array:
	isc_mem_put(mctx, rdatas, nrdatas * sizeof(dns_rdata_t));
cleanup_context:
	dst_context_destroy(&ctx);
cleanup_struct:
	dns_rdata_freestruct(&sig);

	if (ret == ISC_R_SUCCESS && labels - sig.labels > 0) {
		if (wild != NULL) 
			RUNTIME_CHECK(dns_name_concatenate(dns_wildcardname,
					         dns_fixedname_name(&fnewname),
						 wild, NULL) == ISC_R_SUCCESS);
		ret = DNS_R_FROMWILDCARD;
	}
	return (ret);
}
Esempio n. 16
0
isc_result_t
dns_dnssec_sign(dns_name_t *name, dns_rdataset_t *set, dst_key_t *key,
		isc_stdtime_t *inception, isc_stdtime_t *expire,
		isc_mem_t *mctx, isc_buffer_t *buffer, dns_rdata_t *sigrdata)
{
	dns_rdata_rrsig_t sig;
	dns_rdata_t tmpsigrdata;
	dns_rdata_t *rdatas;
	int nrdatas, i;
	isc_buffer_t sigbuf, envbuf;
	isc_region_t r;
	dst_context_t *ctx = NULL;
	isc_result_t ret;
	isc_buffer_t *databuf = NULL;
	char data[256 + 8];
	isc_uint32_t flags;
	unsigned int sigsize;
	dns_fixedname_t fnewname;

	REQUIRE(name != NULL);
	REQUIRE(dns_name_countlabels(name) <= 255);
	REQUIRE(set != NULL);
	REQUIRE(key != NULL);
	REQUIRE(inception != NULL);
	REQUIRE(expire != NULL);
	REQUIRE(mctx != NULL);
	REQUIRE(sigrdata != NULL);

	if (*inception >= *expire)
		return (DNS_R_INVALIDTIME);

	/*
	 * Is the key allowed to sign data?
	 */
	flags = dst_key_flags(key);
	if (flags & DNS_KEYTYPE_NOAUTH)
		return (DNS_R_KEYUNAUTHORIZED);
	if ((flags & DNS_KEYFLAG_OWNERMASK) != DNS_KEYOWNER_ZONE)
		return (DNS_R_KEYUNAUTHORIZED);

	sig.mctx = mctx;
	sig.common.rdclass = set->rdclass;
	sig.common.rdtype = dns_rdatatype_rrsig;
	ISC_LINK_INIT(&sig.common, link);

	dns_name_init(&sig.signer, NULL);
	dns_name_clone(dst_key_name(key), &sig.signer);

	sig.covered = set->type;
	sig.algorithm = dst_key_alg(key);
	sig.labels = dns_name_countlabels(name) - 1;
	if (dns_name_iswildcard(name))
		sig.labels--;
	sig.originalttl = set->ttl;
	sig.timesigned = *inception;
	sig.timeexpire = *expire;
	sig.keyid = dst_key_id(key);
	ret = dst_key_sigsize(key, &sigsize);
	if (ret != ISC_R_SUCCESS)
		return (ret);
	sig.siglen = sigsize;
	/*
	 * The actual contents of sig.signature are not important yet, since
	 * they're not used in digest_sig().
	 */
	sig.signature = isc_mem_get(mctx, sig.siglen);
	if (sig.signature == NULL)
		return (ISC_R_NOMEMORY);

	ret = isc_buffer_allocate(mctx, &databuf, sigsize + 256 + 18);
	if (ret != ISC_R_SUCCESS)
		goto cleanup_signature;

	dns_rdata_init(&tmpsigrdata);
	ret = dns_rdata_fromstruct(&tmpsigrdata, sig.common.rdclass,
				   sig.common.rdtype, &sig, databuf);
	if (ret != ISC_R_SUCCESS)
		goto cleanup_databuf;

	ret = dst_context_create(key, mctx, &ctx);
	if (ret != ISC_R_SUCCESS)
		goto cleanup_databuf;

	/*
	 * Digest the SIG rdata.
	 */
	ret = digest_sig(ctx, &tmpsigrdata, &sig);
	if (ret != ISC_R_SUCCESS)
		goto cleanup_context;

	dns_fixedname_init(&fnewname);
	RUNTIME_CHECK(dns_name_downcase(name, dns_fixedname_name(&fnewname),
					NULL) == ISC_R_SUCCESS);
	dns_name_toregion(dns_fixedname_name(&fnewname), &r);

	/*
	 * Create an envelope for each rdata: <name|type|class|ttl>.
	 */
	isc_buffer_init(&envbuf, data, sizeof(data));
	memcpy(data, r.base, r.length);
	isc_buffer_add(&envbuf, r.length);
	isc_buffer_putuint16(&envbuf, set->type);
	isc_buffer_putuint16(&envbuf, set->rdclass);
	isc_buffer_putuint32(&envbuf, set->ttl);

	ret = rdataset_to_sortedarray(set, mctx, &rdatas, &nrdatas);
	if (ret != ISC_R_SUCCESS)
		goto cleanup_context;
	isc_buffer_usedregion(&envbuf, &r);

	for (i = 0; i < nrdatas; i++) {
		isc_uint16_t len;
		isc_buffer_t lenbuf;
		isc_region_t lenr;

		/*
		 * Skip duplicates.
		 */
		if (i > 0 && dns_rdata_compare(&rdatas[i], &rdatas[i-1]) == 0)
		    continue;

		/*
		 * Digest the envelope.
		 */
		ret = dst_context_adddata(ctx, &r);
		if (ret != ISC_R_SUCCESS)
			goto cleanup_array;

		/*
		 * Digest the length of the rdata.
		 */
		isc_buffer_init(&lenbuf, &len, sizeof(len));
		INSIST(rdatas[i].length < 65536);
		isc_buffer_putuint16(&lenbuf, (isc_uint16_t)rdatas[i].length);
		isc_buffer_usedregion(&lenbuf, &lenr);
		ret = dst_context_adddata(ctx, &lenr);
		if (ret != ISC_R_SUCCESS)
			goto cleanup_array;

		/*
		 * Digest the rdata.
		 */
		ret = dns_rdata_digest(&rdatas[i], digest_callback, ctx);
		if (ret != ISC_R_SUCCESS)
			goto cleanup_array;
	}

	isc_buffer_init(&sigbuf, sig.signature, sig.siglen);
	ret = dst_context_sign(ctx, &sigbuf);
	if (ret != ISC_R_SUCCESS)
		goto cleanup_array;
	isc_buffer_usedregion(&sigbuf, &r);
	if (r.length != sig.siglen) {
		ret = ISC_R_NOSPACE;
		goto cleanup_array;
	}
	memcpy(sig.signature, r.base, sig.siglen);

	ret = dns_rdata_fromstruct(sigrdata, sig.common.rdclass,
				  sig.common.rdtype, &sig, buffer);

cleanup_array:
	isc_mem_put(mctx, rdatas, nrdatas * sizeof(dns_rdata_t));
cleanup_context:
	dst_context_destroy(&ctx);
cleanup_databuf:
	isc_buffer_free(&databuf);
cleanup_signature:
	isc_mem_put(mctx, sig.signature, sig.siglen);

	return (ret);
}
Esempio n. 17
0
static isc_result_t
opensslrsa_todns(const dst_key_t *key, isc_buffer_t *data) {
	isc_region_t r;
	unsigned int e_bytes;
	unsigned int mod_bytes;
	isc_result_t ret;
	RSA *rsa;
#if USE_EVP
	EVP_PKEY *pkey;
#endif

#if USE_EVP
	REQUIRE(key->keydata.pkey != NULL);
#else
	REQUIRE(key->keydata.rsa != NULL);
#endif

#if USE_EVP
	pkey = key->keydata.pkey;
	rsa = EVP_PKEY_get1_RSA(pkey);
	if (rsa == NULL)
		return (dst__openssl_toresult(DST_R_OPENSSLFAILURE));
#else
	rsa = key->keydata.rsa;
#endif

	isc_buffer_availableregion(data, &r);

	e_bytes = BN_num_bytes(rsa->e);
	mod_bytes = BN_num_bytes(rsa->n);

	if (e_bytes < 256) {	/*%< key exponent is <= 2040 bits */
		if (r.length < 1)
			DST_RET(ISC_R_NOSPACE);
		isc_buffer_putuint8(data, (isc_uint8_t) e_bytes);
		isc_region_consume(&r, 1);
	} else {
		if (r.length < 3)
			DST_RET(ISC_R_NOSPACE);
		isc_buffer_putuint8(data, 0);
		isc_buffer_putuint16(data, (isc_uint16_t) e_bytes);
		isc_region_consume(&r, 3);
	}

	if (r.length < e_bytes + mod_bytes)
		DST_RET(ISC_R_NOSPACE);

	BN_bn2bin(rsa->e, r.base);
	isc_region_consume(&r, e_bytes);
	BN_bn2bin(rsa->n, r.base);

	isc_buffer_add(data, e_bytes + mod_bytes);

	ret = ISC_R_SUCCESS;
 err:
#if USE_EVP
	if (rsa != NULL)
		RSA_free(rsa);
#endif
	return (ret);
}
Esempio n. 18
0
static isc_result_t
add_tsig(dst_context_t *tsigctx, dns_tsigkey_t *key, isc_buffer_t *target) {
	dns_compress_t cctx;
	dns_rdata_any_tsig_t tsig;
	dns_rdata_t rdata = DNS_RDATA_INIT;
	dns_rdatalist_t rdatalist;
	dns_rdataset_t rdataset;
	isc_buffer_t *dynbuf = NULL;
	isc_buffer_t databuf;
	isc_buffer_t sigbuf;
	isc_region_t r;
	isc_result_t result = ISC_R_SUCCESS;
	isc_stdtime_t now;
	unsigned char tsigbuf[1024];
	unsigned int count;
	unsigned int sigsize;
	isc_boolean_t invalidate_ctx = ISC_FALSE;

	CHECK(dns_compress_init(&cctx, -1, mctx));
	invalidate_ctx = ISC_TRUE;

	memset(&tsig, 0, sizeof(tsig));
	       tsig.common.rdclass = dns_rdataclass_any;
	tsig.common.rdtype = dns_rdatatype_tsig;
	ISC_LINK_INIT(&tsig.common, link);
	dns_name_init(&tsig.algorithm, NULL);
	dns_name_clone(key->algorithm, &tsig.algorithm);

	isc_stdtime_get(&now);
	tsig.timesigned = now;
	tsig.fudge = DNS_TSIG_FUDGE;
	tsig.originalid = 50;
	tsig.error = dns_rcode_noerror;
	tsig.otherlen = 0;
	tsig.other = NULL;

	isc_buffer_init(&databuf, tsigbuf, sizeof(tsigbuf));
	isc_buffer_putuint48(&databuf, tsig.timesigned);
	isc_buffer_putuint16(&databuf, tsig.fudge);
	isc_buffer_usedregion(&databuf, &r);
	CHECK(dst_context_adddata(tsigctx, &r));

	CHECK(dst_key_sigsize(key->key, &sigsize));
	tsig.signature = (unsigned char *) isc_mem_get(mctx, sigsize);
	if (tsig.signature == NULL)
		CHECK(ISC_R_NOMEMORY);
	isc_buffer_init(&sigbuf, tsig.signature, sigsize);
	CHECK(dst_context_sign(tsigctx, &sigbuf));
	tsig.siglen = isc_buffer_usedlength(&sigbuf);

	CHECK(isc_buffer_allocate(mctx, &dynbuf, 512));
	CHECK(dns_rdata_fromstruct(&rdata, dns_rdataclass_any,
				   dns_rdatatype_tsig, &tsig, dynbuf));
	dns_rdatalist_init(&rdatalist);
	rdatalist.rdclass = dns_rdataclass_any;
	rdatalist.type = dns_rdatatype_tsig;
	ISC_LIST_APPEND(rdatalist.rdata, &rdata, link);
	dns_rdataset_init(&rdataset);
	CHECK(dns_rdatalist_tordataset(&rdatalist, &rdataset));
	CHECK(dns_rdataset_towire(&rdataset, &key->name, &cctx,
				  target, 0, &count));

	/*
	 * Fixup additional record count.
	 */
	((unsigned char*)target->base)[11]++;
	if (((unsigned char*)target->base)[11] == 0)
		((unsigned char*)target->base)[10]++;
 cleanup:
	if (tsig.signature != NULL)
		isc_mem_put(mctx, tsig.signature, sigsize);
	if (dynbuf != NULL)
		isc_buffer_free(&dynbuf);
	if (invalidate_ctx)
		dns_compress_invalidate(&cctx);

	return (result);
}
Esempio n. 19
0
/*
 * Arrange to send as much as we can of "stream" without blocking.
 *
 * Requires:
 *	The stream iterator is initialized and points at an RR,
 *      or possibly at the end of the stream (that is, the
 *      _first method of the iterator has been called).
 */
static void
sendstream(xfrout_ctx_t *xfr) {
	dns_message_t *tcpmsg = NULL;
	dns_message_t *msg = NULL; /* Client message if UDP, tcpmsg if TCP */
	isc_result_t result;
	isc_region_t used;
	isc_region_t region;
	dns_rdataset_t *qrdataset;
	dns_name_t *msgname = NULL;
	dns_rdata_t *msgrdata = NULL;
	dns_rdatalist_t *msgrdl = NULL;
	dns_rdataset_t *msgrds = NULL;
	dns_compress_t cctx;
	isc_boolean_t cleanup_cctx = ISC_FALSE;
	isc_boolean_t is_tcp;

	int n_rrs;

	isc_buffer_clear(&xfr->buf);
	isc_buffer_clear(&xfr->txlenbuf);
	isc_buffer_clear(&xfr->txbuf);

	is_tcp = ISC_TF((xfr->client->attributes & NS_CLIENTATTR_TCP) != 0);
	if (!is_tcp) {
		/*
		 * In the UDP case, we put the response data directly into
		 * the client message.
		 */
		msg = xfr->client->message;
		CHECK(dns_message_reply(msg, ISC_TRUE));
	} else {
		/*
		 * TCP. Build a response dns_message_t, temporarily storing
		 * the raw, uncompressed owner names and RR data contiguously
		 * in xfr->buf.  We know that if the uncompressed data fits
		 * in xfr->buf, the compressed data will surely fit in a TCP
		 * message.
		 */

		CHECK(dns_message_create(xfr->mctx,
					 DNS_MESSAGE_INTENTRENDER, &tcpmsg));
		msg = tcpmsg;

		msg->id = xfr->id;
		msg->rcode = dns_rcode_noerror;
		msg->flags = DNS_MESSAGEFLAG_QR | DNS_MESSAGEFLAG_AA;
		if ((xfr->client->attributes & NS_CLIENTATTR_RA) != 0)
			msg->flags |= DNS_MESSAGEFLAG_RA;
		CHECK(dns_message_settsigkey(msg, xfr->tsigkey));
		CHECK(dns_message_setquerytsig(msg, xfr->lasttsig));
		if (xfr->lasttsig != NULL)
			isc_buffer_free(&xfr->lasttsig);

		/*
		 * Add a EDNS option to the message?
		 */
		if ((xfr->client->attributes & NS_CLIENTATTR_WANTOPT) != 0) {
			dns_rdataset_t *opt = NULL;

			CHECK(ns_client_addopt(xfr->client, msg, &opt));
			CHECK(dns_message_setopt(msg, opt));
			/*
			 * Add to first message only.
			 */
			xfr->client->attributes &= ~NS_CLIENTATTR_WANTNSID;
			xfr->client->attributes &= ~NS_CLIENTATTR_HAVEEXPIRE;
		}

		/*
		 * Account for reserved space.
		 */
		if (xfr->tsigkey != NULL)
			INSIST(msg->reserved != 0U);
		isc_buffer_add(&xfr->buf, msg->reserved);

		/*
		 * Include a question section in the first message only.
		 * BIND 8.2.1 will not recognize an IXFR if it does not
		 * have a question section.
		 */
		if (xfr->nmsg == 0) {
			dns_name_t *qname = NULL;
			isc_region_t r;

			/*
			 * Reserve space for the 12-byte message header
			 * and 4 bytes of question.
			 */
			isc_buffer_add(&xfr->buf, 12 + 4);

			qrdataset = NULL;
			result = dns_message_gettemprdataset(msg, &qrdataset);
			if (result != ISC_R_SUCCESS)
				goto failure;
			dns_rdataset_makequestion(qrdataset,
					xfr->client->message->rdclass,
					xfr->qtype);

			result = dns_message_gettempname(msg, &qname);
			if (result != ISC_R_SUCCESS)
				goto failure;
			dns_name_init(qname, NULL);
			isc_buffer_availableregion(&xfr->buf, &r);
			INSIST(r.length >= xfr->qname->length);
			r.length = xfr->qname->length;
			isc_buffer_putmem(&xfr->buf, xfr->qname->ndata,
					  xfr->qname->length);
			dns_name_fromregion(qname, &r);
			ISC_LIST_INIT(qname->list);
			ISC_LIST_APPEND(qname->list, qrdataset, link);

			dns_message_addname(msg, qname, DNS_SECTION_QUESTION);
		} else {
			/*
			 * Reserve space for the 12-byte message header
			 */
			isc_buffer_add(&xfr->buf, 12);
			msg->tcp_continuation = 1;
		}
	}

	/*
	 * Try to fit in as many RRs as possible, unless "one-answer"
	 * format has been requested.
	 */
	for (n_rrs = 0; ; n_rrs++) {
		dns_name_t *name = NULL;
		isc_uint32_t ttl;
		dns_rdata_t *rdata = NULL;

		unsigned int size;
		isc_region_t r;

		msgname = NULL;
		msgrdata = NULL;
		msgrdl = NULL;
		msgrds = NULL;

		xfr->stream->methods->current(xfr->stream,
					      &name, &ttl, &rdata);
		size = name->length + 10 + rdata->length;
		isc_buffer_availableregion(&xfr->buf, &r);
		if (size >= r.length) {
			/*
			 * RR would not fit.  If there are other RRs in the
			 * buffer, send them now and leave this RR to the
			 * next message.  If this RR overflows the buffer
			 * all by itself, fail.
			 *
			 * In theory some RRs might fit in a TCP message
			 * when compressed even if they do not fit when
			 * uncompressed, but surely we don't want
			 * to send such monstrosities to an unsuspecting
			 * slave.
			 */
			if (n_rrs == 0) {
				xfrout_log(xfr, ISC_LOG_WARNING,
					   "RR too large for zone transfer "
					   "(%d bytes)", size);
				/* XXX DNS_R_RRTOOLARGE? */
				result = ISC_R_NOSPACE;
				goto failure;
			}
			break;
		}

		if (isc_log_wouldlog(ns_g_lctx, XFROUT_RR_LOGLEVEL))
			log_rr(name, rdata, ttl); /* XXX */

		result = dns_message_gettempname(msg, &msgname);
		if (result != ISC_R_SUCCESS)
			goto failure;
		dns_name_init(msgname, NULL);
		isc_buffer_availableregion(&xfr->buf, &r);
		INSIST(r.length >= name->length);
		r.length = name->length;
		isc_buffer_putmem(&xfr->buf, name->ndata, name->length);
		dns_name_fromregion(msgname, &r);

		/* Reserve space for RR header. */
		isc_buffer_add(&xfr->buf, 10);

		result = dns_message_gettemprdata(msg, &msgrdata);
		if (result != ISC_R_SUCCESS)
			goto failure;
		isc_buffer_availableregion(&xfr->buf, &r);
		r.length = rdata->length;
		isc_buffer_putmem(&xfr->buf, rdata->data, rdata->length);
		dns_rdata_init(msgrdata);
		dns_rdata_fromregion(msgrdata,
				     rdata->rdclass, rdata->type, &r);

		result = dns_message_gettemprdatalist(msg, &msgrdl);
		if (result != ISC_R_SUCCESS)
			goto failure;
		msgrdl->type = rdata->type;
		msgrdl->rdclass = rdata->rdclass;
		msgrdl->ttl = ttl;
		if (rdata->type == dns_rdatatype_sig ||
		    rdata->type == dns_rdatatype_rrsig)
			msgrdl->covers = dns_rdata_covers(rdata);
		else
			msgrdl->covers = dns_rdatatype_none;
		ISC_LIST_APPEND(msgrdl->rdata, msgrdata, link);

		result = dns_message_gettemprdataset(msg, &msgrds);
		if (result != ISC_R_SUCCESS)
			goto failure;
		result = dns_rdatalist_tordataset(msgrdl, msgrds);
		INSIST(result == ISC_R_SUCCESS);

		ISC_LIST_APPEND(msgname->list, msgrds, link);

		dns_message_addname(msg, msgname, DNS_SECTION_ANSWER);
		msgname = NULL;

		result = xfr->stream->methods->next(xfr->stream);
		if (result == ISC_R_NOMORE) {
			xfr->end_of_stream = ISC_TRUE;
			break;
		}
		CHECK(result);

		if (! xfr->many_answers)
			break;
		/*
		 * At this stage, at least 1 RR has been rendered into
		 * the message. Check if we want to clamp this message
		 * here (TCP only). 20480 was set as an upper limit to
		 * improve message compression.
		 */
		if ((isc_buffer_usedlength(&xfr->buf) >= 20480) && is_tcp)
			break;
	}

	if (is_tcp) {
		CHECK(dns_compress_init(&cctx, -1, xfr->mctx));
		dns_compress_setsensitive(&cctx, ISC_TRUE);
		cleanup_cctx = ISC_TRUE;
		CHECK(dns_message_renderbegin(msg, &cctx, &xfr->txbuf));
		CHECK(dns_message_rendersection(msg, DNS_SECTION_QUESTION, 0));
		CHECK(dns_message_rendersection(msg, DNS_SECTION_ANSWER, 0));
		CHECK(dns_message_renderend(msg));
		dns_compress_invalidate(&cctx);
		cleanup_cctx = ISC_FALSE;

		isc_buffer_usedregion(&xfr->txbuf, &used);
		isc_buffer_putuint16(&xfr->txlenbuf,
				     (isc_uint16_t)used.length);
		region.base = xfr->txlenbuf.base;
		region.length = 2 + used.length;
		xfrout_log(xfr, ISC_LOG_DEBUG(8),
			   "sending TCP message of %d bytes",
			   used.length);
		CHECK(isc_socket_send(xfr->client->tcpsocket, /* XXX */
				      &region, xfr->client->task,
				      xfrout_senddone,
				      xfr));
		xfr->sends++;
	} else {
		xfrout_log(xfr, ISC_LOG_DEBUG(8), "sending IXFR UDP response");
		ns_client_send(xfr->client);
		xfr->stream->methods->pause(xfr->stream);
		xfrout_ctx_destroy(&xfr);
		return;
	}

	/* Advance lasttsig to be the last TSIG generated */
	CHECK(dns_message_getquerytsig(msg, xfr->mctx, &xfr->lasttsig));

	xfr->nmsg++;

 failure:
	if (msgname != NULL) {
		if (msgrds != NULL) {
			if (dns_rdataset_isassociated(msgrds))
				dns_rdataset_disassociate(msgrds);
			dns_message_puttemprdataset(msg, &msgrds);
		}
		if (msgrdl != NULL) {
			ISC_LIST_UNLINK(msgrdl->rdata, msgrdata, link);
			dns_message_puttemprdatalist(msg, &msgrdl);
		}
		if (msgrdata != NULL)
			dns_message_puttemprdata(msg, &msgrdata);
		dns_message_puttempname(msg, &msgname);
	}

	if (tcpmsg != NULL)
		dns_message_destroy(&tcpmsg);

	if (cleanup_cctx)
		dns_compress_invalidate(&cctx);
	/*
	 * Make sure to release any locks held by database
	 * iterators before returning from the event handler.
	 */
	xfr->stream->methods->pause(xfr->stream);

	if (result == ISC_R_SUCCESS)
		return;

	xfrout_fail(xfr, result, "sending zone data");
}
Esempio n. 20
0
isc_result_t
dns_ncache_add(dns_message_t *message, dns_db_t *cache, dns_dbnode_t *node,
	       dns_rdatatype_t covers, isc_stdtime_t now, dns_ttl_t maxttl,
	       dns_rdataset_t *addedrdataset)
{
	isc_result_t result;
	isc_buffer_t buffer;
	isc_region_t r;
	dns_rdataset_t *rdataset;
	dns_rdatatype_t type;
	dns_name_t *name;
	dns_ttl_t ttl;
	dns_trust_t trust;
	dns_rdata_t rdata = DNS_RDATA_INIT;
	dns_rdataset_t ncrdataset;
	dns_rdatalist_t ncrdatalist;
	unsigned char data[4096];

	/*
	 * Convert the authority data from 'message' into a negative cache
	 * rdataset, and store it in 'cache' at 'node'.
	 */

	REQUIRE(message != NULL);

	/*
	 * We assume that all data in the authority section has been
	 * validated by the caller.
	 */

	/*
	 * First, build an ncache rdata in buffer.
	 */
	ttl = maxttl;
	trust = 0xffff;
	isc_buffer_init(&buffer, data, sizeof(data));
	if (message->counts[DNS_SECTION_AUTHORITY])
		result = dns_message_firstname(message, DNS_SECTION_AUTHORITY);
	else
		result = ISC_R_NOMORE;
	while (result == ISC_R_SUCCESS) {
		name = NULL;
		dns_message_currentname(message, DNS_SECTION_AUTHORITY,
					&name);
		if ((name->attributes & DNS_NAMEATTR_NCACHE) != 0) {
			for (rdataset = ISC_LIST_HEAD(name->list);
			     rdataset != NULL;
			     rdataset = ISC_LIST_NEXT(rdataset, link)) {
				if ((rdataset->attributes &
				     DNS_RDATASETATTR_NCACHE) == 0)
					continue;
				type = rdataset->type;
				if (type == dns_rdatatype_rrsig)
					type = rdataset->covers;
				if (type == dns_rdatatype_soa ||
				    type == dns_rdatatype_nsec) {
					if (ttl > rdataset->ttl)
						ttl = rdataset->ttl;
					if (trust > rdataset->trust)
						trust = rdataset->trust;
					/*
					 * Copy the owner name to the buffer.
					 */
					dns_name_toregion(name, &r);
					result = isc_buffer_copyregion(&buffer,
								       &r);
					if (result != ISC_R_SUCCESS)
						return (result);
					/*
					 * Copy the type to the buffer.
					 */
					isc_buffer_availableregion(&buffer,
								   &r);
					if (r.length < 2)
						return (ISC_R_NOSPACE);
					isc_buffer_putuint16(&buffer,
							     rdataset->type);
					/*
					 * Copy the rdataset into the buffer.
					 */
					result = copy_rdataset(rdataset,
							       &buffer);
					if (result != ISC_R_SUCCESS)
						return (result);
				}
			}
		}
		result = dns_message_nextname(message, DNS_SECTION_AUTHORITY);
	}
	if (result != ISC_R_NOMORE)
		return (result);

	if (trust == 0xffff) {
		/*
		 * We didn't find any authority data from which to create a
		 * negative cache rdataset.  In particular, we have no SOA.
		 *
		 * We trust that the caller wants negative caching, so this
		 * means we have a "type 3 nxdomain" or "type 3 nodata"
		 * response (see RFC 2308 for details).
		 *
		 * We will now build a suitable negative cache rdataset that
		 * will cause zero bytes to be emitted when converted to
		 * wire format.
		 */

		/*
		 * The ownername must exist, but it doesn't matter what value
		 * it has.  We use the root name.
		 */
		dns_name_toregion(dns_rootname, &r);
		result = isc_buffer_copyregion(&buffer, &r);
		if (result != ISC_R_SUCCESS)
			return (result);
		/*
		 * Copy the type and a zero rdata count to the buffer.
		 */
		isc_buffer_availableregion(&buffer, &r);
		if (r.length < 4)
			return (ISC_R_NOSPACE);
		isc_buffer_putuint16(&buffer, 0);
		isc_buffer_putuint16(&buffer, 0);
		/*
		 * RFC 2308, section 5, says that negative answers without
		 * SOAs should not be cached.
		 */
		ttl = 0;
		/*
		 * Set trust.
		 */
		if ((message->flags & DNS_MESSAGEFLAG_AA) != 0 &&
		    message->counts[DNS_SECTION_ANSWER] == 0) {
			/*
			 * The response has aa set and we haven't followed
			 * any CNAME or DNAME chains.
			 */
			trust = dns_trust_authauthority;
		} else
			trust = dns_trust_additional;
	}

	/*
	 * Now add it to the cache.
	 */
	INSIST(trust != 0xffff);
	isc_buffer_usedregion(&buffer, &r);
	rdata.data = r.base;
	rdata.length = r.length;
	rdata.rdclass = dns_db_class(cache);
	rdata.type = 0;
	rdata.flags = 0;

	ncrdatalist.rdclass = rdata.rdclass;
	ncrdatalist.type = 0;
	ncrdatalist.covers = covers;
	ncrdatalist.ttl = ttl;
	ISC_LIST_INIT(ncrdatalist.rdata);
	ISC_LINK_INIT(&ncrdatalist, link);

	ISC_LIST_APPEND(ncrdatalist.rdata, &rdata, link);

	dns_rdataset_init(&ncrdataset);
	RUNTIME_CHECK(dns_rdatalist_tordataset(&ncrdatalist, &ncrdataset)
		      == ISC_R_SUCCESS);
	ncrdataset.trust = trust;
	if (message->rcode == dns_rcode_nxdomain)
		ncrdataset.attributes |= DNS_RDATASETATTR_NXDOMAIN;

	return (dns_db_addrdataset(cache, node, NULL, now, &ncrdataset,
				   0, addedrdataset));
}