From 6023c69c616d866e19ab1c0bb87931e5143c79d3 Mon Sep 17 00:00:00 2001

From: Daiki Ueno <dueno@redhat.com>

Date: Wed, 5 Jun 2019 16:48:39 +0200

Subject: [PATCH] tls13/key_update: ignore multiple key updates instead of

 error

This fixes the multiple KeyUpdate messages handling in commit

65e2aa80d114d4bef095d129c2eda475e473244a, where illegal_parameter is

sent even if the limit doesn't exceed.

Signed-off-by: Daiki Ueno <dueno@redhat.com>

---

 .gitignore                        |   1 +

 lib/tls13/key_update.c            |   2 -

 tests/Makefile.am                 |   2 +

 tests/tls13/key_update_multiple.c | 232 ++++++++++++++++++++++++++++++

 4 files changed, 235 insertions(+), 2 deletions(-)

 create mode 100644 tests/tls13/key_update_multiple.c

diff --git a/lib/tls13/key_update.c b/lib/tls13/key_update.c

index d542a214b..c6f6e0aa1 100644

--- a/lib/tls13/key_update.c

+++ b/lib/tls13/key_update.c

@@ -117,8 +117,6 @@ int _gnutls13_recv_key_update(gnutls_session_t session, gnutls_buffer_st *buf)

 			session->internals.rsend_state = RECORD_SEND_KEY_UPDATE_1;

 		else if (session->internals.rsend_state == RECORD_SEND_CORKED)

 			session->internals.rsend_state = RECORD_SEND_CORKED_TO_KU;

-		else

-			return gnutls_assert_val(GNUTLS_E_RECEIVED_ILLEGAL_PARAMETER);

 		break;

 	default:

diff --git a/tests/Makefile.am b/tests/Makefile.am

index ca0481879..4ffa69825 100644

--- a/tests/Makefile.am

+++ b/tests/Makefile.am

@@ -119,6 +119,8 @@ ctests += tls13/psk-ext

 ctests += tls13/key_update

+ctests += tls13/key_update_multiple

+

 ctests += tls13/key_limits

 ctests += tls13/multi-ocsp

diff --git a/tests/tls13/key_update_multiple.c b/tests/tls13/key_update_multiple.c

new file mode 100644

index 000000000..8b2c2db4b

--- /dev/null

+++ b/tests/tls13/key_update_multiple.c

@@ -0,0 +1,232 @@

+/*

+ * Copyright (C) 2017-2019 Red Hat, Inc.

+ *

+ * Author: Daiki Ueno

+ *

+ * This file is part of GnuTLS.

+ *

+ * GnuTLS is free software; you can redistribute it and/or modify it

+ * under the terms of the GNU General Public License as published by

+ * the Free Software Foundation; either version 3 of the License, or

+ * (at your option) any later version.

+ *

+ * GnuTLS is distributed in the hope that it will be useful, but

+ * WITHOUT ANY WARRANTY; without even the implied warranty of

+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

+ * General Public License for more details.

+ *

+ * You should have received a copy of the GNU Lesser General Public License

+ * along with this program.  If not, see <https://www.gnu.org/licenses/>

+ */

+

+#ifdef HAVE_CONFIG_H

+#include <config.h>

+#endif

+

+#include <stdbool.h>

+#include <stdio.h>

+#include <stdlib.h>

+#include <string.h>

+#include <errno.h>

+#include <gnutls/gnutls.h>

+#include <gnutls/crypto.h>

+#include <assert.h>

+#include "cert-common.h"

+

+#include "utils.h"

+#include "virt-time.h"

+#define RANDOMIZE

+#include "eagain-common.h"

+

+const char *side = "";

+

+/* This program tests whether multiple key update messages are handled

+ * properly with rate-limit. */

+

+static void tls_log_func(int level, const char *str)

+{

+	fprintf(stderr, "%s|<%d>| %s", side, level, str);

+}

+

+#define MAX_BUF 1024

+#define MSG "Hello TLS, and hi and how are you and more data here... and more... and even more and even more more data..."

+

+/* These must match the definitions in lib/tls13/key_update.c. */

+#define KEY_UPDATES_WINDOW 1000

+#define KEY_UPDATES_PER_WINDOW 8

+

+static unsigned key_update_msg_inc = 0;

+static unsigned key_update_msg_out = 0;

+

+static int hsk_callback(gnutls_session_t session, unsigned int htype,

+			unsigned post, unsigned int incoming, const gnutls_datum_t *msg)

+{

+	assert(post == GNUTLS_HOOK_PRE);

+

+	assert(msg->size == 1);

+

+	if (htype == GNUTLS_HANDSHAKE_KEY_UPDATE) {

+		if (incoming)

+			key_update_msg_inc++;

+		else

+			key_update_msg_out++;

+	}

+

+	return 0;

+}

+

+static void run(const char *name, bool exceed_limit)

+{

+	/* Server stuff. */

+	gnutls_certificate_credentials_t ccred;

+	gnutls_certificate_credentials_t scred;

+	gnutls_session_t server;

+	int sret, cret;

+	/* Client stuff. */

+	gnutls_session_t client;

+	/* Need to enable anonymous KX specifically. */

+	char buffer[MAX_BUF + 1];

+	int ret, transferred = 0;

+	size_t i;

+

+	success("%s\n", name);

+

+	/* General init. */

+	global_init();

+	gnutls_global_set_log_function(tls_log_func);

+	if (debug)

+		gnutls_global_set_log_level(9);

+

+	/* Init server */

+	assert(gnutls_certificate_allocate_credentials(&scred) >= 0);

+	assert(gnutls_certificate_set_x509_key_mem(scred,

+						   &server_ca3_localhost_cert,

+						   &server_ca3_key,

+						   GNUTLS_X509_FMT_PEM) >= 0);

+

+	assert(gnutls_init(&server, GNUTLS_SERVER) >= 0);

+	ret =

+	    gnutls_priority_set_direct(server,

+				       "NORMAL:-VERS-TLS-ALL:+VERS-TLS1.3",

+				       NULL);

+	if (ret < 0)

+		exit(1);

+

+	gnutls_credentials_set(server, GNUTLS_CRD_CERTIFICATE, scred);

+	gnutls_transport_set_push_function(server, server_push);

+	gnutls_transport_set_pull_function(server, server_pull);

+	gnutls_transport_set_ptr(server, server);

+

+	/* Init client */

+	assert(gnutls_certificate_allocate_credentials(&ccred) >= 0);

+	assert(gnutls_certificate_set_x509_trust_mem

+	       (ccred, &ca3_cert, GNUTLS_X509_FMT_PEM) >= 0);

+

+	gnutls_init(&client, GNUTLS_CLIENT);

+	ret =

+	    gnutls_priority_set_direct(client,

+				       "NORMAL:-VERS-TLS-ALL:+VERS-TLS1.3",

+				       NULL);

+	assert(ret >= 0);

+

+	ret = gnutls_credentials_set(client, GNUTLS_CRD_CERTIFICATE, ccred);

+	if (ret < 0)

+		exit(1);

+

+	gnutls_transport_set_push_function(client, client_push);

+	gnutls_transport_set_pull_function(client, client_pull);

+	gnutls_transport_set_ptr(client, client);

+

+

+	HANDSHAKE(client, server);

+	if (debug)

+		success("Handshake established\n");

+

+	key_update_msg_inc = 0;

+	key_update_msg_out = 0;

+

+	gnutls_handshake_set_hook_function(client, -1, GNUTLS_HOOK_PRE, hsk_callback);

+

+	/* schedule multiple key updates */

+	for (i = 0; i < KEY_UPDATES_PER_WINDOW; i++) {

+		do {

+			ret = gnutls_session_key_update(client, 1);

+		} while (ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED);

+		if (ret < 0)

+			fail("error in key update: %s\n", gnutls_strerror(ret));

+	}

+

+	/* server receives the client key update and sends data */

+	TRANSFER(client, server, MSG, strlen(MSG), buffer, MAX_BUF);

+	TRANSFER(server, client, MSG, strlen(MSG), buffer, MAX_BUF);

+	EMPTY_BUF(server, client, buffer, MAX_BUF);

+

+	if (key_update_msg_out != KEY_UPDATES_PER_WINDOW)

+		fail("unexpected number of key updates are sent: %d\n",

+			key_update_msg_out);

+	else {

+		if (debug)

+			success("successfully sent %d key updates\n",

+				KEY_UPDATES_PER_WINDOW);

+	}

+	if (key_update_msg_inc != 1)

+		fail("unexpected number of key updates received: %d\n",

+			key_update_msg_inc);

+	else {

+		if (debug)

+			success("successfully received 1 key update\n");

+	}

+

+	if (exceed_limit) {

+		/* excessive key update in the same time window should

+		 * be rejected by the peer */

+		do {

+			ret = gnutls_session_key_update(client, 1);

+		} while (ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED);

+

+		/* server receives the client key update and sends data */

+		ret = record_send_loop(client, MSG, strlen(MSG), 0);

+		assert(ret == strlen(MSG));

+		ret = gnutls_record_recv(server, buffer, MAX_BUF);

+		if (ret != GNUTLS_E_TOO_MANY_HANDSHAKE_PACKETS)

+			fail("server didn't reject excessive number of key updates\n");

+		else {

+			if (debug)

+				success("server rejected excessive number of key updates\n");

+		}

+	} else {

+		virt_sec_sleep(KEY_UPDATES_WINDOW / 1000 + 1);

+

+		/* the time window should be rolled over now */

+		do {

+			ret = gnutls_session_key_update(client, 1);

+		} while (ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED);

+		if (ret < 0)

+			fail("error in key update: %s\n", gnutls_strerror(ret));

+

+		/* server receives the client key update and sends data */

+		TRANSFER(client, server, MSG, strlen(MSG), buffer, MAX_BUF);

+		TRANSFER(server, client, MSG, strlen(MSG), buffer, MAX_BUF);

+		EMPTY_BUF(server, client, buffer, MAX_BUF);

+	}

+

+	gnutls_bye(client, GNUTLS_SHUT_WR);

+	gnutls_bye(server, GNUTLS_SHUT_WR);

+

+	gnutls_deinit(client);

+	gnutls_deinit(server);

+

+	gnutls_certificate_free_credentials(scred);

+	gnutls_certificate_free_credentials(ccred);

+

+	gnutls_global_deinit();

+	reset_buffers();

+}

+

+void doit(void)

+{

+	virt_time_init();

+

+	run("not exceeding limit", 0);

+	run("exceeding limit", 1);

+}

-- 

2.20.1