Add new default siphash24 cookie algorithm, but keep AES as legacy

This commit changes the BIND cookie algorithms to match
draft-sury-toorop-dnsop-server-cookies-00.  Namely, it changes the Client Cookie
algorithm to use SipHash 2-4, adds the new Server Cookie algorithm using SipHash
2-4, and changes the default for the Server Cookie algorithm to be siphash24.

Add siphash24 cookie algorithm, and make it keep legacy aes as

bin/named/config.c

@@ -50,7 +50,7 @@ options {\n\
 	automatic-interface-scan yes;\n\
 	bindkeys-file \"" NAMED_SYSCONFDIR "/bind.keys\";\n\
 #	blackhole {none;};\n"
-"	cookie-algorithm aes;\n"
+"	cookie-algorithm siphash24;\n"
 #ifndef WIN32
 "	coresize default;\n\
 	datasize default;\n"

bin/named/named.conf.docbook

@@ -222,7 +222,7 @@ options {
 	check-srv-cname ( fail | warn | ignore );
 	check-wildcard <replaceable>boolean</replaceable>;
 	clients-per-query <replaceable>integer</replaceable>;
-	cookie-algorithm ( aes );
+	cookie-algorithm ( aes | siphash24 );
 	cookie-secret <replaceable>string</replaceable>;
 	coresize ( default | unlimited | <replaceable>sizeval</replaceable> );
 	datasize ( default | unlimited | <replaceable>sizeval</replaceable> );

bin/named/server.c

@@ -39,6 +39,7 @@
 #include <isc/print.h>
 #include <isc/refcount.h>
 #include <isc/resource.h>
+#include <isc/siphash.h>
 #include <isc/socket.h>
 #include <isc/stat.h>
 #include <isc/stats.h>
@@ -9129,7 +9130,9 @@ load_configuration(const char *filename, named_server_t *server,
 	obj = NULL;
 	result = named_config_get(maps, "cookie-algorithm", &obj);
 	INSIST(result == ISC_R_SUCCESS);
-	if (strcasecmp(cfg_obj_asstring(obj), "aes") == 0) {
+	if (strcasecmp(cfg_obj_asstring(obj), "siphash24") == 0) {
+		server->sctx->cookiealg = ns_cookiealg_siphash24;
+	} else if (strcasecmp(cfg_obj_asstring(obj), "aes") == 0) {
 		server->sctx->cookiealg = ns_cookiealg_aes;
 	} else {
 		INSIST(0);
@@ -9188,12 +9191,18 @@ load_configuration(const char *filename, named_server_t *server,
 
 			usedlength = isc_buffer_usedlength(&b);
 			switch (server->sctx->cookiealg) {
+			case ns_cookiealg_siphash24:
+				expectedlength = ISC_SIPHASH24_KEY_LENGTH;
+				if (usedlength != expectedlength) {
+					CHECKM(ISC_R_RANGE,
+					       "SipHash-2-4 cookie-secret must be 128 bits");
+				}
+				break;
 			case ns_cookiealg_aes:
 				expectedlength = ISC_AES128_KEYLENGTH;
 				if (usedlength != expectedlength) {
 					CHECKM(ISC_R_RANGE,
-					       "AES cookie-secret must be "
+					       "AES cookie-secret must be 128 bits");
-					       "128 bits");
 				}
 				break;
 			}

bin/tests/system/cookie/bad-cookie-badaes.conf

@@ -10,6 +10,6 @@
  */
 
 options {
-	cookie-algorithm sha1;
+	cookie-algorithm aes;
-	cookie-secret "ebc7701beabb4a40c57d140eeb6733fafba4272f";  // 160 bits
+	cookie-secret "ebc7701beabb4a40c57d140eeb6733faaa";  // 136 bits
 };

bin/tests/system/cookie/bad-cookie-badsiphash24.conf

@@ -10,6 +10,6 @@
  */
 
 options {
-	cookie-algorithm sha256;
+	cookie-algorithm siphash24;
-	cookie-secret "ebc7701beabb4a40c57d140eeb6733fafba4272f";  // 160 bits
+	cookie-secret "ebc7701beabb4a40c57d140eeb6733faaabbccdd";  // 160 bits
 };

bin/tests/system/cookie/good-cookie-aes.conf

@@ -10,6 +10,6 @@
  */
 
 options {
-	cookie-algorithm sha1;
+	cookie-algorithm aes;
-	cookie-secret "ebc7701beabb4a40c57d140eeb6733fafba4272fff";  // 168 bits
+	cookie-secret "ebc7701beabb4a40c57d140eeb6733fa";  // 128 bits
 };

bin/tests/system/cookie/good-cookie-siphash24.conf

@@ -10,6 +10,6 @@
  */
 
 options {
-	cookie-algorithm sha256;
+	cookie-algorithm siphash24;
-	cookie-secret "b174e3800b6734f73268f15831c957860a8ee1229cfb9039c1514836f53efbed";
+	cookie-secret "ebc7701beabb4a40c57d140eeb6733fa";  // 128 bits
 };

bin/tests/system/cookie/ns4/named.conf.in

@@ -28,8 +28,8 @@ options {
 	listen-on-v6 { none; };
 	recursion yes;
 	dnssec-validation yes;
-	cookie-algorithm sha1;
+	cookie-algorithm siphash24;
-	cookie-secret "569d36a6cc27d6bf55502183302ba352745255a2";
+	cookie-secret "569d36a6cc27d6bf55502183302ba352";
 	require-server-cookie yes;
 };
 

bin/tests/system/cookie/ns5/named.conf.in

@@ -28,9 +28,9 @@ options {
 	listen-on-v6 { none; };
 	recursion yes;
 	dnssec-validation yes;
-	cookie-algorithm sha1;
+	cookie-algorithm siphash24;
-	cookie-secret "569d36a6cc27d6bf55502183302ba352745255a2";
+	cookie-secret "569d36a6cc27d6bf55502183302ba352";
-	cookie-secret "6b300e27a0db46d4b046e4189790fa7db3c1ffb3";
+	cookie-secret "6b300e27a0db46d4b046e4189790fa7d";
 	require-server-cookie yes;
 };
 

bin/tests/system/cookie/ns6/named.conf.in

@@ -28,8 +28,8 @@ options {
 	listen-on-v6 { none; };
 	recursion yes;
 	dnssec-validation yes;
-	cookie-algorithm sha1;
+	cookie-algorithm siphash24;
-	cookie-secret "6b300e27a0db46d4b046e4189790fa7db3c1ffb3";
+	cookie-secret "6b300e27a0db46d4b046e4189790fa7d";
 	require-server-cookie yes;
 };
 

bin/tests/system/cookie/tests.sh

@@ -211,12 +211,12 @@ status=`expr $status + $ret`
 #
 # Test shared cookie-secret support.
 #
-# NS4 has cookie-secret "569d36a6cc27d6bf55502183302ba352745255a2";
+# NS4 has cookie-secret "569d36a6cc27d6bf55502183302ba352";
 #
-# NS5 has cookie-secret "569d36a6cc27d6bf55502183302ba352745255a2";
+# NS5 has cookie-secret "569d36a6cc27d6bf55502183302ba352";
-# NS5 has cookie-secret "6b300e27a0db46d4b046e4189790fa7db3c1ffb3"; (alternate)
+# NS5 has cookie-secret "6b300e27a0db46d4b046e4189790fa7d"; (alternate)
 #
-# NS6 has cookie-secret "6b300e27a0db46d4b046e4189790fa7db3c1ffb3";
+# NS6 has cookie-secret "6b300e27a0db46d4b046e4189790fa7d";
 #
 # Server cookies from NS4 are accepted by NS5 and not NS6
 # Server cookies from NS5 are accepted by NS4 and not NS6

configure

@@ -850,7 +850,6 @@ infodir
 docdir
 oldincludedir
 includedir
-runstatedir
 localstatedir
 sharedstatedir
 sysconfdir
@@ -1019,7 +1018,6 @@ datadir='${datarootdir}'
 sysconfdir='${prefix}/etc'
 sharedstatedir='${prefix}/com'
 localstatedir='${prefix}/var'
-runstatedir='${localstatedir}/run'
 includedir='${prefix}/include'
 oldincludedir='/usr/include'
 docdir='${datarootdir}/doc/${PACKAGE_TARNAME}'
@@ -1272,15 +1270,6 @@ do
   | -silent | --silent | --silen | --sile | --sil)
     silent=yes ;;
 
-  -runstatedir | --runstatedir | --runstatedi | --runstated \
-  | --runstate | --runstat | --runsta | --runst | --runs \
-  | --run | --ru | --r)
-    ac_prev=runstatedir ;;
-  -runstatedir=* | --runstatedir=* | --runstatedi=* | --runstated=* \
-  | --runstate=* | --runstat=* | --runsta=* | --runst=* | --runs=* \
-  | --run=* | --ru=* | --r=*)
-    runstatedir=$ac_optarg ;;
-
   -sbindir | --sbindir | --sbindi | --sbind | --sbin | --sbi | --sb)
     ac_prev=sbindir ;;
   -sbindir=* | --sbindir=* | --sbindi=* | --sbind=* | --sbin=* \
@@ -1418,7 +1407,7 @@ fi
 for ac_var in	exec_prefix prefix bindir sbindir libexecdir datarootdir \
 		datadir sysconfdir sharedstatedir localstatedir includedir \
 		oldincludedir docdir infodir htmldir dvidir pdfdir psdir \
-		libdir localedir mandir runstatedir
+		libdir localedir mandir
 do
   eval ac_val=\$$ac_var
   # Remove trailing slashes.
@@ -1571,7 +1560,6 @@ Fine tuning of the installation directories:
   --sysconfdir=DIR        read-only single-machine data [PREFIX/etc]
   --sharedstatedir=DIR    modifiable architecture-independent data [PREFIX/com]
   --localstatedir=DIR     modifiable single-machine data [PREFIX/var]
-  --runstatedir=DIR       modifiable per-process data [LOCALSTATEDIR/run]
   --libdir=DIR            object code libraries [EPREFIX/lib]
   --includedir=DIR        C header files [PREFIX/include]
   --oldincludedir=DIR     C header files for non-gcc [/usr/include]
@@ -4010,7 +3998,7 @@ else
     We can't simply define LARGE_OFF_T to be 9223372036854775807,
     since some C++ compilers masquerading as C compilers
     incorrectly reject 9223372036854775807.  */
-#define LARGE_OFF_T ((((off_t) 1 << 31) << 31) - 1 + (((off_t) 1 << 31) << 31))
+#define LARGE_OFF_T (((off_t) 1 << 62) - 1 + ((off_t) 1 << 62))
   int off_t_is_large[(LARGE_OFF_T % 2147483629 == 721
 		       && LARGE_OFF_T % 2147483647 == 1)
 		      ? 1 : -1];
@@ -4056,7 +4044,7 @@ else
     We can't simply define LARGE_OFF_T to be 9223372036854775807,
     since some C++ compilers masquerading as C compilers
     incorrectly reject 9223372036854775807.  */
-#define LARGE_OFF_T ((((off_t) 1 << 31) << 31) - 1 + (((off_t) 1 << 31) << 31))
+#define LARGE_OFF_T (((off_t) 1 << 62) - 1 + ((off_t) 1 << 62))
   int off_t_is_large[(LARGE_OFF_T % 2147483629 == 721
 		       && LARGE_OFF_T % 2147483647 == 1)
 		      ? 1 : -1];
@@ -4080,7 +4068,7 @@ rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
     We can't simply define LARGE_OFF_T to be 9223372036854775807,
     since some C++ compilers masquerading as C compilers
     incorrectly reject 9223372036854775807.  */
-#define LARGE_OFF_T ((((off_t) 1 << 31) << 31) - 1 + (((off_t) 1 << 31) << 31))
+#define LARGE_OFF_T (((off_t) 1 << 62) - 1 + ((off_t) 1 << 62))
   int off_t_is_large[(LARGE_OFF_T % 2147483629 == 721
 		       && LARGE_OFF_T % 2147483647 == 1)
 		      ? 1 : -1];
@@ -4125,7 +4113,7 @@ else
     We can't simply define LARGE_OFF_T to be 9223372036854775807,
     since some C++ compilers masquerading as C compilers
     incorrectly reject 9223372036854775807.  */
-#define LARGE_OFF_T ((((off_t) 1 << 31) << 31) - 1 + (((off_t) 1 << 31) << 31))
+#define LARGE_OFF_T (((off_t) 1 << 62) - 1 + ((off_t) 1 << 62))
   int off_t_is_large[(LARGE_OFF_T % 2147483629 == 721
 		       && LARGE_OFF_T % 2147483647 == 1)
 		      ? 1 : -1];
@@ -4149,7 +4137,7 @@ rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
     We can't simply define LARGE_OFF_T to be 9223372036854775807,
     since some C++ compilers masquerading as C compilers
     incorrectly reject 9223372036854775807.  */
-#define LARGE_OFF_T ((((off_t) 1 << 31) << 31) - 1 + (((off_t) 1 << 31) << 31))
+#define LARGE_OFF_T (((off_t) 1 << 62) - 1 + ((off_t) 1 << 62))
   int off_t_is_large[(LARGE_OFF_T % 2147483629 == 721
 		       && LARGE_OFF_T % 2147483647 == 1)
 		      ? 1 : -1];

doc/misc/options

@@ -113,7 +113,7 @@ options {
         check-wildcard <boolean>;
         cleaning-interval <integer>; // obsolete
         clients-per-query <integer>;
-        cookie-algorithm ( aes );
+        cookie-algorithm ( aes | siphash24 );
         cookie-secret <string>; // may occur multiple times
         coresize ( default | unlimited | <sizeval> );
         datasize ( default | unlimited | <sizeval> );

lib/bind9/check.c

@@ -29,6 +29,7 @@
 #include <isc/print.h>
 #include <isc/region.h>
 #include <isc/result.h>
+#include <isc/siphash.h>
 #include <isc/sockaddr.h>
 #include <isc/string.h>
 #include <isc/symtab.h>
@@ -857,7 +858,7 @@ check_options(const cfg_obj_t *options, isc_log_t *logctx, isc_mem_t *mctx,
 	dns_name_t *name;
 	isc_buffer_t b;
 	uint32_t lifetime = 3600;
-	const char *ccalg = "aes";
+	const char *ccalg = "siphash24";
 
 	/*
 	 * { "name", scale, value }
@@ -1350,8 +1351,14 @@ check_options(const cfg_obj_t *options, isc_log_t *logctx, isc_mem_t *mctx,
 			if (strcasecmp(ccalg, "aes") == 0 &&
 			    usedlength != ISC_AES128_KEYLENGTH) {
 				cfg_obj_log(obj, logctx, ISC_LOG_ERROR,
-					    "AES cookie-secret must be "
+					    "AES cookie-secret must be 128 bits");
-					    "128 bits");
+				if (result == ISC_R_SUCCESS)
+					result = ISC_R_RANGE;
+			}
+			if (strcasecmp(ccalg, "siphash24") == 0 &&
+			    usedlength != ISC_SIPHASH24_KEY_LENGTH) {
+				cfg_obj_log(obj, logctx, ISC_LOG_ERROR,
+					    "SipHash-2-4 cookie-secret must be 128 bits");
 				if (result == ISC_R_SUCCESS)
 					result = ISC_R_RANGE;
 			}

lib/dns/resolver.c

@@ -21,14 +21,13 @@
 #include <isc/print.h>
 #include <isc/string.h>
 #include <isc/random.h>
+#include <isc/siphash.h>
 #include <isc/socket.h>
 #include <isc/stats.h>
 #include <isc/task.h>
 #include <isc/timer.h>
 #include <isc/util.h>
 
-#include <isc/aes.h>
-
 #include <dns/acl.h>
 #include <dns/adb.h>
 #include <dns/badcache.h>
@@ -201,7 +200,7 @@ typedef struct query {
 	isc_mem_t *			mctx;
 	dns_dispatchmgr_t *		dispatchmgr;
 	dns_dispatch_t *		dispatch;
-	bool			exclusivesocket;
+	bool				exclusivesocket;
 	dns_adbaddrinfo_t *		addrinfo;
 	isc_socket_t *			tcpsocket;
 	isc_time_t			start;
@@ -213,7 +212,7 @@ typedef struct query {
 	dns_tsigkey_t			*tsigkey;
 	isc_socketevent_t		sendevent;
 	isc_dscp_t			dscp;
-	int 				ednsversion;
+	int				ednsversion;
 	unsigned int			options;
 	isc_sockeventattr_t		attributes;
 	unsigned int			sends;
@@ -2271,29 +2270,56 @@ add_triededns512(fetchctx_t *fctx, isc_sockaddr_t *address) {
 	ISC_LIST_INITANDAPPEND(fctx->edns512, tried, link);
 }
 
-static void
+static inline size_t
-compute_cc(resquery_t *query, unsigned char *cookie, size_t len) {
+addr2buf(void *buf, const size_t bufsize, const isc_sockaddr_t *sockaddr) {
-	unsigned char digest[ISC_AES_BLOCK_LENGTH];
-	unsigned char input[16];
 	isc_netaddr_t netaddr;
-	unsigned int i;
+	isc_netaddr_fromsockaddr(&netaddr, sockaddr);
-
-	INSIST(len >= 8U);
-
-	isc_netaddr_fromsockaddr(&netaddr, &query->addrinfo->sockaddr);
 	switch (netaddr.family) {
 	case AF_INET:
-		memmove(input, (unsigned char *)&netaddr.type.in, 4);
+		INSIST(bufsize >= 4);
-		memset(input + 4, 0, 12);
+		memmove(buf, &netaddr.type.in, 4);
-		break;
+		return (4);
 	case AF_INET6:
-		memmove(input, (unsigned char *)&netaddr.type.in6, 16);
+		INSIST(bufsize >= 16);
-		break;
+		memmove(buf, &netaddr.type.in6, 16);
+		return (16);
+	default:
+		INSIST(0);
+		ISC_UNREACHABLE();
 	}
-	isc_aes128_crypt(query->fctx->res->view->secret, input, digest);
+	return (0);
-	for (i = 0; i < 8; i++)
+}
-		digest[i] ^= digest[i + 8];
+
-	memmove(cookie, digest, 8);
+static inline isc_socket_t *
+query2sock(const resquery_t *query) {
+	if (query->exclusivesocket) {
+		return (dns_dispatch_getentrysocket(query->dispentry));
+	} else {
+		return (dns_dispatch_getsocket(query->dispatch));
+	}
+}
+
+static inline size_t
+add_serveraddr(uint8_t *buf, const size_t bufsize, const resquery_t *query)
+{
+	return (addr2buf(buf, bufsize, &query->addrinfo->sockaddr));
+}
+
+#define CLIENT_COOKIE_SIZE 8U
+
+static void
+compute_cc(const resquery_t *query, uint8_t *cookie, const size_t len) {
+	INSIST(len >= CLIENT_COOKIE_SIZE);
+	STATIC_ASSERT(sizeof(query->fctx->res->view->secret)
+		      >= ISC_SIPHASH24_KEY_LENGTH,
+		      "The view->secret size can't fit SipHash 2-4 key length");
+
+	uint8_t buf[16] ISC_NONSTRING = { 0 };
+	size_t buflen = add_serveraddr(buf, sizeof(buf), query);
+
+	uint8_t digest[ISC_SIPHASH24_TAG_LENGTH] ISC_NONSTRING = { 0 };
+	isc_siphash24(query->fctx->res->view->secret, buf, buflen, digest);
+	memmove(cookie, digest, CLIENT_COOKIE_SIZE);
 }
 
 static isc_result_t
@@ -2753,10 +2779,8 @@ resquery_send(resquery_t *query) {
 	 */
 	dns_message_reset(fctx->qmessage, DNS_MESSAGE_INTENTRENDER);
 
-	if (query->exclusivesocket)
+	sock = query2sock(query);
-		sock = dns_dispatch_getentrysocket(query->dispentry);
+
-	else
-		sock = dns_dispatch_getsocket(query->dispatch);
 	/*
 	 * Send the query!
 	 */
@@ -5334,9 +5358,9 @@ validated(isc_task_t *task, isc_event_t *event) {
 	REQUIRE(event->ev_type == DNS_EVENT_VALIDATORDONE);
 	valarg = event->ev_arg;
 	fctx = valarg->fctx;
+	REQUIRE(VALID_FCTX(fctx));
 	res = fctx->res;
 	addrinfo = valarg->addrinfo;
-	REQUIRE(VALID_FCTX(fctx));
 	REQUIRE(!ISC_LIST_EMPTY(fctx->validators));
 
 	vevent = (dns_validatorevent_t *)event;
@@ -9548,11 +9572,7 @@ rctx_logpacket(respctx_t *rctx) {
 		dtmsgtype = DNS_DTTYPE_RR;
 	}
 
-	if (rctx->query->exclusivesocket) {
+	sock = query2sock(rctx->query);
-		sock = dns_dispatch_getentrysocket(rctx->query->dispentry);
-	} else {
-		sock = dns_dispatch_getsocket(rctx->query->dispatch);
-	}
 
 	if (sock != NULL) {
 		result = isc_socket_getsockname(sock, &localaddr);

lib/isc/include/isc/util.h

@@ -42,6 +42,12 @@
  */
 #define UNUSED(x)      (void)(x)
 
+#if __GNUC__ >= 8 && !defined(__clang__)
+#define ISC_NONSTRING	__attribute__((nonstring))
+#else
+#define ISC_NONSTRING
+#endif /* __GNUC__ */
+
 /*%
  * The opposite: silent warnings about stored values which are never read.
  */

lib/isccfg/namedconf.c

@@ -899,7 +899,7 @@ static cfg_type_t cfg_type_bracketed_portlist = {
 	&cfg_rep_list, &cfg_type_portrange
 };
 
-static const char *cookiealg_enums[] = { "aes", NULL };
+static const char *cookiealg_enums[] = { "aes", "siphash24", NULL };
 static cfg_type_t cfg_type_cookiealg = {
 	"cookiealg", cfg_parse_enum, cfg_print_ustring, cfg_doc_enum,
 	&cfg_rep_string, &cookiealg_enums

lib/ns/client.c

@@ -25,6 +25,7 @@
 #include <isc/random.h>
 #include <isc/safe.h>
 #include <isc/serial.h>
+#include <isc/siphash.h>
 #include <isc/stats.h>
 #include <isc/stdio.h>
 #include <isc/string.h>
@@ -1919,23 +1920,63 @@ static void
 compute_cookie(ns_client_t *client, uint32_t when, uint32_t nonce,
 	       const unsigned char *secret, isc_buffer_t *buf)
 {
+	unsigned char digest[ISC_MAX_MD_SIZE] ISC_NONSTRING = { 0 };;
+	STATIC_ASSERT(ISC_MAX_MD_SIZE >= ISC_SIPHASH24_TAG_LENGTH,
+		      "You need to increase the digest buffer.");
+	STATIC_ASSERT(ISC_MAX_MD_SIZE >= ISC_AES_BLOCK_LENGTH,
+		      "You need to increase the digest buffer.");
+
 	switch (client->sctx->cookiealg) {
+	case ns_cookiealg_siphash24: {
+		unsigned char input[16 + 16] ISC_NONSTRING = { 0 };
+		size_t inputlen = 0;
+		isc_netaddr_t netaddr;
+		unsigned char *cp;
+
+		cp = isc_buffer_used(buf);
+		isc_buffer_putmem(buf, client->cookie, 8);
+		isc_buffer_putuint8(buf, NS_COOKIE_VERSION_1);
+		isc_buffer_putuint24(buf, 0); /* Reserved */
+		isc_buffer_putuint32(buf, when);
+
+		memmove(input, cp, 16);
+
+		isc_netaddr_fromsockaddr(&netaddr, &client->peeraddr);
+		switch (netaddr.family) {
+		case AF_INET:
+			cp = (unsigned char *)&netaddr.type.in;
+			memmove(input + 16, cp, 4);
+			inputlen = 20;
+			break;
+		case AF_INET6:
+			cp = (unsigned char *)&netaddr.type.in6;
+			memmove(input + 16, cp, 16);
+			inputlen = 32;
+			break;
+		default:
+			INSIST(0);
+			ISC_UNREACHABLE();
+		}
+
+		isc_siphash24(secret, input, inputlen, digest);
+		isc_buffer_putmem(buf, digest, 8);
+		break;
+	}
 	case ns_cookiealg_aes: {
-		unsigned char digest[ISC_AES_BLOCK_LENGTH];
+		unsigned char input[4 + 4 + 16] ISC_NONSTRING = { 0 };
-		unsigned char input[4 + 4 + 16];
 		isc_netaddr_t netaddr;
 		unsigned char *cp;
 		unsigned int i;
 
-		memset(input, 0, sizeof(input));
 		cp = isc_buffer_used(buf);
 		isc_buffer_putmem(buf, client->cookie, 8);
 		isc_buffer_putuint32(buf, nonce);
 		isc_buffer_putuint32(buf, when);
 		memmove(input, cp, 16);
 		isc_aes128_crypt(secret, input, digest);
-		for (i = 0; i < 8; i++)
+		for (i = 0; i < 8; i++) {
 			input[i] = digest[i] ^ digest[i + 8];
+		}
 		isc_netaddr_fromsockaddr(&netaddr, &client->peeraddr);
 		switch (netaddr.family) {
 		case AF_INET:
@@ -1948,14 +1989,19 @@ compute_cookie(ns_client_t *client, uint32_t when, uint32_t nonce,
 			cp = (unsigned char *)&netaddr.type.in6;
 			memmove(input + 8, cp, 16);
 			isc_aes128_crypt(secret, input, digest);
-			for (i = 0; i < 8; i++)
+			for (i = 0; i < 8; i++) {
 				input[i + 8] = digest[i] ^ digest[i + 8];
+			}
 			isc_aes128_crypt(client->sctx->secret, input + 8,
 					 digest);
 			break;
+		default:
+			INSIST(0);
+			ISC_UNREACHABLE();
 		}
-		for (i = 0; i < 8; i++)
+		for (i = 0; i < 8; i++) {
 			digest[i] ^= digest[i + 8];
+		}
 		isc_buffer_putmem(buf, digest, 8);
 		break;
 	}

lib/ns/include/ns/types.h

@@ -27,7 +27,10 @@ typedef struct ns_server		ns_server_t;
 typedef struct ns_stats			ns_stats_t;
 
 typedef enum {
-	ns_cookiealg_aes
+	ns_cookiealg_aes,
+	ns_cookiealg_siphash24
 } ns_cookiealg_t;
 
+#define NS_COOKIE_VERSION_1 1
+
 #endif /* NS_TYPES_H */