ext/record_size_limit: distinguish sending and receiving limitstmp-record-sizes

The previous behavior was that both sending and receiving limits are
negotiated to be the same value.  It was problematic when:

- client sends a record_size_limit with a large value in CH
- server sends a record_size_limit with a smaller value in EE
- client updates the limit for both sending and receiving, upon
  receiving EE
- server sends a Certificate message larger than the limit

With this patch, each peer maintains the sending / receiving limits
separately so not to confuse with the contradicting settings.

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

2 files changed, 279 insertions, 1 deletions

diff --git a/tests/Makefile.am b/tests/Makefile.am
index 940e1ba605..eb65e94858 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -208,7 +208,8 @@ ctests += mini-record-2 simple gnutls_hmac_fast set_pkcs12_cred cert certuniquei
 	 dss-sig-val sign-pk-api tls-session-ext-override record-pad \
 	 tls13-server-kx-neg gnutls_ext_raw_parse_dtls key-export-pkcs8 \
 	 null_retrieve_function tls-record-size-limit tls-crt_type-neg \
-	 resume-with-stek-expiration resume-with-previous-stek rawpk-api
+	 resume-with-stek-expiration resume-with-previous-stek rawpk-api \
+	 tls-record-size-limit-asym
 
 if HAVE_SECCOMP_TESTS
 ctests += dtls-with-seccomp tls-with-seccomp dtls-client-with-seccomp tls-client-with-seccomp
diff --git a/tests/tls-record-size-limit-asym.c b/tests/tls-record-size-limit-asym.c
new file mode 100644
index 0000000000..1fd8289883
--- /dev/null
+++ b/tests/tls-record-size-limit-asym.c
@@ -0,0 +1,277 @@
+/*
+ * Copyright (C) 2015, 2019 Red Hat, Inc.
+ *
+ * Author: Nikos Mavrogiannopoulos, 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 General Public License
+ * along with GnuTLS; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
+ */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <assert.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+#include <gnutls/gnutls.h>
+#include "utils.h"
+
+#include "eagain-common.h"
+
+#include "cert-common.h"
+
+/* This tests whether the max-record extension is respected on TLS.
+ */
+
+const char *side;
+
+static void tls_log_func(int level, const char *str)
+{
+	fprintf(stderr, "%s|<%d>| %s", side, level, str);
+}
+
+#define MAX_BUF 16384
+static char buffer[MAX_BUF];
+
+struct test_exp_st {
+	int error;
+	size_t size;
+};
+
+struct test_st {
+	const char *prio;
+	size_t server_max_size;
+	size_t client_max_size;
+
+	struct test_exp_st server_exp;
+	struct test_exp_st client_exp;
+};
+
+static void start(const struct test_st *test)
+{
+	int ret;
+	/* Server stuff. */
+	gnutls_certificate_credentials_t serverx509cred;
+	gnutls_session_t server;
+	int sret = GNUTLS_E_AGAIN;
+	/* Client stuff. */
+	gnutls_certificate_credentials_t clientx509cred;
+	gnutls_session_t client;
+	int cret = GNUTLS_E_AGAIN;
+
+	printf("testing server limit %d and client limit %d in %s\n",
+	       (int)test->server_max_size, (int)test->client_max_size,
+	       test->prio);
+
+	global_init();
+
+	/* General init. */
+	gnutls_global_set_log_function(tls_log_func);
+	if (debug)
+		gnutls_global_set_log_level(6);
+
+	/* Init server */
+	assert(gnutls_certificate_allocate_credentials(&serverx509cred) >= 0);
+	assert(gnutls_certificate_set_x509_key_mem(serverx509cred,
+						   &server2_cert, &server2_key,
+						   GNUTLS_X509_FMT_PEM) >= 0);
+
+	assert(gnutls_init(&server, GNUTLS_SERVER) >= 0);
+	assert(gnutls_credentials_set(server, GNUTLS_CRD_CERTIFICATE,
+				      serverx509cred) >= 0);
+
+	assert(gnutls_priority_set_direct(server, test->prio, NULL) >= 0);
+
+	ret = gnutls_record_set_max_recv_size(server, test->server_max_size);
+	if (ret != test->server_exp.error)
+		fail("server: unexpected error from gnutls_record_set_max_recv_size()");
+
+	gnutls_transport_set_push_function(server, server_push);
+	gnutls_transport_set_pull_function(server, server_pull);
+	gnutls_transport_set_pull_timeout_function(server,
+						   server_pull_timeout_func);
+	gnutls_transport_set_ptr(server, server);
+
+
+	/* Init client */
+	assert(gnutls_certificate_allocate_credentials(&clientx509cred) >= 0);
+
+	assert(gnutls_certificate_set_x509_trust_mem(clientx509cred, &ca2_cert, GNUTLS_X509_FMT_PEM) >= 0);
+
+	assert(gnutls_init(&client, GNUTLS_CLIENT) >= 0);
+
+	assert(gnutls_credentials_set(client, GNUTLS_CRD_CERTIFICATE,
+				      clientx509cred) >= 0);
+
+	assert(gnutls_priority_set_direct(client, test->prio, NULL) >= 0);
+
+	ret = gnutls_record_set_max_recv_size(client, test->client_max_size);
+	if (ret != test->client_exp.error)
+		fail("client: unexpected error from gnutls_record_set_max_recv_size()");
+
+	gnutls_transport_set_push_function(client, client_push);
+	gnutls_transport_set_pull_function(client, client_pull);
+	gnutls_transport_set_pull_timeout_function(client,
+						   client_pull_timeout_func);
+	gnutls_transport_set_ptr(client, client);
+
+	HANDSHAKE(client, server);
+
+	memset(buffer, 1, sizeof(buffer));
+	ret = gnutls_record_send(server, buffer, test->client_max_size + 1);
+	if (ret < 0) {
+		gnutls_perror(ret);
+		exit(1);
+	}
+	if (ret != (int)test->server_exp.size)
+		fail("server: unexpected record size sent: %d (%d)\n",
+		     ret, (int)test->server_exp.size);
+	success("server: did not send a %d-byte packet\n",
+		(int)test->server_exp.size);
+
+	ret = gnutls_record_send(server, buffer, test->client_max_size);
+	if (ret < 0) {
+		gnutls_perror(ret);
+		exit(1);
+	}
+	success("server: did send a %d-byte packet\n",
+		(int)test->client_max_size);
+
+	ret = gnutls_record_send(client, buffer, test->server_max_size + 1);
+	if (ret < 0) {
+		gnutls_perror(ret);
+		exit(1);
+	}
+	if (ret != (int)test->client_exp.size)
+		fail("client: unexpected record size sent: %d (%d)\n",
+		     ret, (int)test->client_exp.size);
+	success("client: did not send a %d-byte packet\n",
+		(int)test->server_max_size + 1);
+
+	ret = gnutls_record_send(client, buffer, test->server_max_size);
+	if (ret < 0) {
+		gnutls_perror(ret);
+		exit(1);
+	}
+	success("client: did send a %d-byte packet\n",
+		(int)test->server_max_size);
+
+	gnutls_bye(client, GNUTLS_SHUT_RDWR);
+	gnutls_bye(server, GNUTLS_SHUT_RDWR);
+
+	gnutls_deinit(client);
+	gnutls_deinit(server);
+
+	gnutls_certificate_free_credentials(serverx509cred);
+	gnutls_certificate_free_credentials(clientx509cred);
+
+	gnutls_global_deinit();
+
+	reset_buffers();
+}
+
+static const struct test_st tests[] = {
+	{
+		.prio = "NORMAL:-VERS-ALL:+VERS-TLS1.2",
+		.server_max_size = 512,
+		.client_max_size = 16384,
+		.server_exp = {
+			.error = 0,
+			.size = 16384,
+		},
+		.client_exp = {
+			.error = 0,
+			.size = 512,
+		}
+	},
+	{
+		.prio = "NORMAL:-VERS-ALL:+VERS-TLS1.2",
+		.server_max_size = 16384,
+		.client_max_size = 512,
+		.server_exp = {
+			.error = 0,
+			.size = 512,
+		},
+		.client_exp = {
+			.error = 0,
+			.size = 16384,
+		}
+	},
+	{
+		.prio = "NORMAL:-VERS-ALL:+VERS-TLS1.3",
+		.server_max_size = 512,
+		.client_max_size = 16384,
+		.server_exp = {
+			.error = 0,
+			.size = 16384,
+		},
+		.client_exp = {
+			.error = 0,
+			.size = 512,
+		}
+	},
+	{
+		.prio = "NORMAL:-VERS-ALL:+VERS-TLS1.3",
+		.server_max_size = 16384,
+		.client_max_size = 512,
+		.server_exp = {
+			.error = 0,
+			.size = 512,
+		},
+		.client_exp = {
+			.error = 0,
+			.size = 16384,
+		}
+	},
+	{
+		.prio = "NORMAL",
+		.server_max_size = 512,
+		.client_max_size = 16384,
+		.server_exp = {
+			.error = 0,
+			.size = 16384,
+		},
+		.client_exp = {
+			.error = 0,
+			.size = 512,
+		}
+	},
+	{
+		.prio = "NORMAL",
+		.server_max_size = 16384,
+		.client_max_size = 512,
+		.server_exp = {
+			.error = 0,
+			.size = 512,
+		},
+		.client_exp = {
+			.error = 0,
+			.size = 16384,
+		}
+	}
+};
+
+void doit(void)
+{
+	size_t i;
+	for (i = 0; i < sizeof(tests)/sizeof(tests[0]); i++)
+		start(&tests[i]);
+}