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/*
* Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License").
* You may not use this file except in compliance with the License.
* A copy of the License is located at
*
* http://aws.amazon.com/apache2.0
*
* or in the "license" file accompanying this file. This file is distributed
* on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
* express or implied. See the License for the specific language governing
* permissions and limitations under the License.
*/
#include "api/s2n.h"
#include "s2n_test.h"
#include "testlib/s2n_testlib.h"
#include "tls/s2n_tls.h"
static S2N_RESULT s2n_write_test_supported_versions_extension(struct s2n_blob *supported_versions_blob, uint8_t version,
uint8_t extension_length)
{
RESULT_ENSURE_REF(supported_versions_blob);
struct s2n_stuffer supported_versions_stuffer = { 0 };
RESULT_GUARD_POSIX(s2n_stuffer_init(&supported_versions_stuffer, supported_versions_blob));
/* Write the length byte. */
RESULT_GUARD_POSIX(s2n_stuffer_write_uint8(&supported_versions_stuffer, extension_length));
/* Write the supported version. */
RESULT_GUARD_POSIX(s2n_stuffer_write_uint8(&supported_versions_stuffer, version / 10));
RESULT_GUARD_POSIX(s2n_stuffer_write_uint8(&supported_versions_stuffer, version % 10));
return S2N_RESULT_OK;
}
struct s2n_overwrite_client_hello_ctx {
uint8_t client_hello_version;
uint8_t client_supported_version;
uint8_t extension_length;
uint8_t supported_versions_data[3];
int invoked_count;
};
static int s2n_overwrite_client_hello_cb(struct s2n_connection *conn, void *ctx)
{
EXPECT_NOT_NULL(conn);
EXPECT_NOT_NULL(ctx);
struct s2n_overwrite_client_hello_ctx *context = (struct s2n_overwrite_client_hello_ctx *) ctx;
context->invoked_count += 1;
if (context->extension_length) {
struct s2n_blob supported_versions_blob = { 0 };
EXPECT_SUCCESS(s2n_blob_init(&supported_versions_blob, context->supported_versions_data,
sizeof(context->supported_versions_data)));
struct s2n_client_hello *client_hello = s2n_connection_get_client_hello(conn);
EXPECT_NOT_NULL(client_hello);
s2n_extension_type_id supported_versions_id = 0;
EXPECT_SUCCESS(s2n_extension_supported_iana_value_to_id(S2N_EXTENSION_SUPPORTED_VERSIONS, &supported_versions_id));
s2n_parsed_extension *extension = &client_hello->extensions.parsed_extensions[supported_versions_id];
EXPECT_OK(s2n_write_test_supported_versions_extension(&supported_versions_blob,
context->client_supported_version, context->extension_length));
extension->extension_type = S2N_EXTENSION_SUPPORTED_VERSIONS;
extension->extension = supported_versions_blob;
}
/* The client version fields are set when parsing the client hello before the client hello
* callback is invoked. The version fields are overridden to emulate receiving a client hello
* with a different version.
*/
if (context->client_hello_version) {
conn->client_hello_version = context->client_hello_version;
conn->client_protocol_version = context->client_hello_version;
}
return S2N_SUCCESS;
}
int main(int argc, char **argv)
{
BEGIN_TEST();
DEFER_CLEANUP(struct s2n_cert_chain_and_key *chain_and_key = NULL, s2n_cert_chain_and_key_ptr_free);
EXPECT_SUCCESS(s2n_test_cert_chain_and_key_new(&chain_and_key,
S2N_DEFAULT_TEST_CERT_CHAIN, S2N_DEFAULT_TEST_PRIVATE_KEY));
/* Safety */
{
EXPECT_FAILURE_WITH_ERRNO(s2n_connection_get_client_protocol_version(NULL), S2N_ERR_NULL);
EXPECT_FAILURE_WITH_ERRNO(s2n_connection_get_client_hello_version(NULL), S2N_ERR_NULL);
EXPECT_FAILURE_WITH_ERRNO(s2n_connection_get_server_protocol_version(NULL), S2N_ERR_NULL);
EXPECT_FAILURE_WITH_ERRNO(s2n_connection_get_actual_protocol_version(NULL), S2N_ERR_NULL);
}
/* Test protocol version getters on the server when a supported versions extension is received */
for (uint8_t server_version = S2N_TLS12; server_version <= S2N_TLS13; server_version++) {
for (uint8_t client_hello_version = S2N_SSLv3; client_hello_version <= S2N_TLS12; client_hello_version++) {
for (uint8_t client_supported_version = S2N_SSLv3; client_supported_version <= S2N_TLS13; client_supported_version++) {
DEFER_CLEANUP(struct s2n_config *config = s2n_config_new(), s2n_config_ptr_free);
EXPECT_SUCCESS(s2n_config_add_cert_chain_and_key_to_store(config, chain_and_key));
if (server_version == S2N_TLS12) {
EXPECT_SUCCESS(s2n_config_set_cipher_preferences(config, "test_all_tls12"));
} else if (s2n_is_tls13_fully_supported()) {
EXPECT_SUCCESS(s2n_config_set_cipher_preferences(config, "test_all"));
} else {
continue;
}
struct s2n_overwrite_client_hello_ctx context = {
.client_hello_version = client_hello_version,
.client_supported_version = client_supported_version,
.extension_length = 2,
};
EXPECT_SUCCESS(s2n_config_set_client_hello_cb(config, s2n_overwrite_client_hello_cb, &context));
DEFER_CLEANUP(struct s2n_connection *client = s2n_connection_new(S2N_CLIENT),
s2n_connection_ptr_free);
EXPECT_NOT_NULL(client);
EXPECT_SUCCESS(s2n_connection_set_config(client, config));
DEFER_CLEANUP(struct s2n_connection *server = s2n_connection_new(S2N_SERVER),
s2n_connection_ptr_free);
EXPECT_NOT_NULL(server);
EXPECT_SUCCESS(s2n_connection_set_config(server, config));
DEFER_CLEANUP(struct s2n_test_io_pair io_pair = { 0 }, s2n_io_pair_close);
EXPECT_SUCCESS(s2n_io_pair_init_non_blocking(&io_pair));
EXPECT_SUCCESS(s2n_connections_set_io_pair(client, server, &io_pair));
EXPECT_OK(s2n_negotiate_test_server_and_client_until_message(server, client, SERVER_HELLO));
EXPECT_EQUAL(context.invoked_count, 1);
/* Ensure that a supported versions extension was received. */
bool supported_versions_received = false;
EXPECT_SUCCESS(s2n_client_hello_has_extension(&server->client_hello, S2N_EXTENSION_SUPPORTED_VERSIONS,
&supported_versions_received));
EXPECT_TRUE(supported_versions_received);
EXPECT_EQUAL(s2n_connection_get_server_protocol_version(server), server_version);
EXPECT_EQUAL(s2n_connection_get_client_hello_version(server), client_hello_version);
/* The reported client protocol version should always match the version specified
* in the supported versions extension, even for TLS 1.2 servers which don't
* process the extension for version selection.
*/
EXPECT_EQUAL(s2n_connection_get_client_protocol_version(server), client_supported_version);
uint8_t actual_protocol_version = s2n_connection_get_actual_protocol_version(server);
if (server_version == S2N_TLS12) {
/* For backwards compatibility, TLS 1.2 servers always use the client hello
* version to determine the client's maximum version, even if a supported
* versions extension was received.
*/
EXPECT_EQUAL(actual_protocol_version, MIN(server_version, client_hello_version));
} else {
/* TLS 1.3 servers always use the version in the supported versions extension,
* regardless of the client hello version.
*/
EXPECT_EQUAL(actual_protocol_version, MIN(server_version, client_supported_version));
}
}
}
}
/* Test protocol version getters on the server when a supported versions extension isn't received */
for (uint8_t server_version = S2N_TLS12; server_version <= S2N_TLS13; server_version++) {
for (uint8_t client_hello_version = S2N_SSLv3; client_hello_version <= S2N_TLS12; client_hello_version++) {
DEFER_CLEANUP(struct s2n_config *client_config = s2n_config_new(), s2n_config_ptr_free);
/* A TLS 1.2 security policy is set to prevent the client from sending a supported
* versions extension.
*/
EXPECT_SUCCESS(s2n_config_set_cipher_preferences(client_config, "test_all_tls12"));
DEFER_CLEANUP(struct s2n_config *server_config = s2n_config_new(), s2n_config_ptr_free);
EXPECT_SUCCESS(s2n_config_add_cert_chain_and_key_to_store(server_config, chain_and_key));
if (server_version == S2N_TLS12) {
EXPECT_SUCCESS(s2n_config_set_cipher_preferences(server_config, "test_all_tls12"));
} else if (s2n_is_tls13_fully_supported()) {
EXPECT_SUCCESS(s2n_config_set_cipher_preferences(server_config, "test_all"));
} else {
continue;
}
struct s2n_overwrite_client_hello_ctx context = {
.client_hello_version = client_hello_version,
};
EXPECT_SUCCESS(s2n_config_set_client_hello_cb(server_config, s2n_overwrite_client_hello_cb, &context));
DEFER_CLEANUP(struct s2n_connection *client = s2n_connection_new(S2N_CLIENT),
s2n_connection_ptr_free);
EXPECT_NOT_NULL(client);
EXPECT_SUCCESS(s2n_connection_set_config(client, client_config));
DEFER_CLEANUP(struct s2n_connection *server = s2n_connection_new(S2N_SERVER),
s2n_connection_ptr_free);
EXPECT_NOT_NULL(server);
EXPECT_SUCCESS(s2n_connection_set_config(server, server_config));
DEFER_CLEANUP(struct s2n_test_io_pair io_pair = { 0 }, s2n_io_pair_close);
EXPECT_SUCCESS(s2n_io_pair_init_non_blocking(&io_pair));
EXPECT_SUCCESS(s2n_connections_set_io_pair(client, server, &io_pair));
EXPECT_OK(s2n_negotiate_test_server_and_client_until_message(server, client, SERVER_HELLO));
EXPECT_EQUAL(context.invoked_count, 1);
/* Ensure that a supported versions extension wasn't received. */
bool supported_versions_received = false;
EXPECT_SUCCESS(s2n_client_hello_has_extension(&server->client_hello, S2N_EXTENSION_SUPPORTED_VERSIONS,
&supported_versions_received));
EXPECT_FALSE(supported_versions_received);
EXPECT_EQUAL(s2n_connection_get_server_protocol_version(server), server_version);
EXPECT_EQUAL(s2n_connection_get_client_protocol_version(server), client_hello_version);
EXPECT_EQUAL(s2n_connection_get_client_hello_version(server), client_hello_version);
EXPECT_EQUAL(s2n_connection_get_actual_protocol_version(server), client_hello_version);
}
}
/* Test protocol version getters on the client */
for (uint8_t server_version = S2N_SSLv3; server_version <= S2N_TLS13; server_version++) {
if (server_version == S2N_TLS13 && !s2n_is_tls13_fully_supported()) {
continue;
}
DEFER_CLEANUP(struct s2n_config *config = s2n_config_new(), s2n_config_ptr_free);
EXPECT_SUCCESS(s2n_config_add_cert_chain_and_key_to_store(config, chain_and_key));
EXPECT_SUCCESS(s2n_config_set_cipher_preferences(config, "test_all"));
DEFER_CLEANUP(struct s2n_connection *client = s2n_connection_new(S2N_CLIENT), s2n_connection_ptr_free);
EXPECT_NOT_NULL(client);
EXPECT_SUCCESS(s2n_connection_set_config(client, config));
DEFER_CLEANUP(struct s2n_connection *server = s2n_connection_new(S2N_SERVER), s2n_connection_ptr_free);
EXPECT_NOT_NULL(server);
EXPECT_SUCCESS(s2n_connection_set_config(server, config));
server->server_protocol_version = server_version;
DEFER_CLEANUP(struct s2n_test_io_pair io_pair = { 0 }, s2n_io_pair_close);
EXPECT_SUCCESS(s2n_io_pair_init_non_blocking(&io_pair));
EXPECT_SUCCESS(s2n_connections_set_io_pair(client, server, &io_pair));
EXPECT_OK(s2n_negotiate_test_server_and_client_until_message(server, client, SERVER_CERT));
EXPECT_EQUAL(s2n_connection_get_server_protocol_version(client), server_version);
EXPECT_EQUAL(s2n_connection_get_client_protocol_version(client), s2n_get_highest_fully_supported_tls_version());
EXPECT_EQUAL(s2n_connection_get_client_hello_version(client), S2N_TLS12);
EXPECT_EQUAL(s2n_connection_get_actual_protocol_version(client), server_version);
}
/* Ensure that TLS 1.2 servers report the client hello version as the client protocol version
* if a malformed supported versions extension was received
*/
for (uint8_t client_hello_version = S2N_SSLv3; client_hello_version <= S2N_TLS12; client_hello_version++) {
DEFER_CLEANUP(struct s2n_config *config = s2n_config_new(), s2n_config_ptr_free);
EXPECT_SUCCESS(s2n_config_add_cert_chain_and_key_to_store(config, chain_and_key));
EXPECT_SUCCESS(s2n_config_set_cipher_preferences(config, "test_all_tls12"));
struct s2n_overwrite_client_hello_ctx context = {
.client_hello_version = client_hello_version,
.client_supported_version = S2N_TLS13,
/* Write an invalid length */
.extension_length = 11,
};
EXPECT_SUCCESS(s2n_config_set_client_hello_cb(config, s2n_overwrite_client_hello_cb, &context));
DEFER_CLEANUP(struct s2n_connection *client = s2n_connection_new(S2N_CLIENT),
s2n_connection_ptr_free);
EXPECT_NOT_NULL(client);
EXPECT_SUCCESS(s2n_connection_set_config(client, config));
DEFER_CLEANUP(struct s2n_connection *server = s2n_connection_new(S2N_SERVER),
s2n_connection_ptr_free);
EXPECT_NOT_NULL(server);
EXPECT_SUCCESS(s2n_connection_set_config(server, config));
DEFER_CLEANUP(struct s2n_test_io_pair io_pair = { 0 }, s2n_io_pair_close);
EXPECT_SUCCESS(s2n_io_pair_init_non_blocking(&io_pair));
EXPECT_SUCCESS(s2n_connections_set_io_pair(client, server, &io_pair));
EXPECT_OK(s2n_negotiate_test_server_and_client_until_message(server, client, SERVER_HELLO));
EXPECT_EQUAL(context.invoked_count, 1);
/* Ensure that a supported versions extension was received. */
bool supported_versions_received = false;
EXPECT_SUCCESS(s2n_client_hello_has_extension(&server->client_hello, S2N_EXTENSION_SUPPORTED_VERSIONS,
&supported_versions_received));
EXPECT_TRUE(supported_versions_received);
EXPECT_EQUAL(s2n_connection_get_client_protocol_version(server), client_hello_version);
}
/* Ensure that TLS 1.2 servers report the client hello version as the client protocol version
* if an invalid supported version is received
*/
for (uint8_t client_hello_version = S2N_SSLv3; client_hello_version <= S2N_TLS12; client_hello_version++) {
DEFER_CLEANUP(struct s2n_config *config = s2n_config_new(), s2n_config_ptr_free);
EXPECT_SUCCESS(s2n_config_add_cert_chain_and_key_to_store(config, chain_and_key));
EXPECT_SUCCESS(s2n_config_set_cipher_preferences(config, "test_all_tls12"));
struct s2n_overwrite_client_hello_ctx context = {
.client_hello_version = client_hello_version,
/* Write an invalid version */
.client_supported_version = S2N_TLS13 + 10,
.extension_length = 2,
};
EXPECT_SUCCESS(s2n_config_set_client_hello_cb(config, s2n_overwrite_client_hello_cb, &context));
DEFER_CLEANUP(struct s2n_connection *client = s2n_connection_new(S2N_CLIENT),
s2n_connection_ptr_free);
EXPECT_NOT_NULL(client);
EXPECT_SUCCESS(s2n_connection_set_config(client, config));
DEFER_CLEANUP(struct s2n_connection *server = s2n_connection_new(S2N_SERVER),
s2n_connection_ptr_free);
EXPECT_NOT_NULL(server);
EXPECT_SUCCESS(s2n_connection_set_config(server, config));
DEFER_CLEANUP(struct s2n_test_io_pair io_pair = { 0 }, s2n_io_pair_close);
EXPECT_SUCCESS(s2n_io_pair_init_non_blocking(&io_pair));
EXPECT_SUCCESS(s2n_connections_set_io_pair(client, server, &io_pair));
EXPECT_OK(s2n_negotiate_test_server_and_client_until_message(server, client, SERVER_HELLO));
EXPECT_EQUAL(context.invoked_count, 1);
/* Ensure that a supported versions extension was received. */
bool supported_versions_received = false;
EXPECT_SUCCESS(s2n_client_hello_has_extension(&server->client_hello, S2N_EXTENSION_SUPPORTED_VERSIONS,
&supported_versions_received));
EXPECT_TRUE(supported_versions_received);
EXPECT_EQUAL(s2n_connection_get_client_protocol_version(server), client_hello_version);
}
/* Ensure that TLS 1.3 servers report an unknown protocol version if a supported versions
* extension can't be processed
*/
if (s2n_is_tls13_fully_supported()) {
DEFER_CLEANUP(struct s2n_config *config = s2n_config_new(), s2n_config_ptr_free);
EXPECT_SUCCESS(s2n_config_add_cert_chain_and_key_to_store(config, chain_and_key));
EXPECT_SUCCESS(s2n_config_set_cipher_preferences(config, "test_all"));
struct s2n_overwrite_client_hello_ctx context = {
.client_supported_version = S2N_TLS13,
/* Write an invalid length */
.extension_length = 11,
};
EXPECT_SUCCESS(s2n_config_set_client_hello_cb(config, s2n_overwrite_client_hello_cb, &context));
DEFER_CLEANUP(struct s2n_connection *client = s2n_connection_new(S2N_CLIENT),
s2n_connection_ptr_free);
EXPECT_NOT_NULL(client);
EXPECT_SUCCESS(s2n_connection_set_config(client, config));
DEFER_CLEANUP(struct s2n_connection *server = s2n_connection_new(S2N_SERVER),
s2n_connection_ptr_free);
EXPECT_NOT_NULL(server);
EXPECT_SUCCESS(s2n_connection_set_config(server, config));
EXPECT_SUCCESS(s2n_connection_set_blinding(server, S2N_SELF_SERVICE_BLINDING));
DEFER_CLEANUP(struct s2n_test_io_pair io_pair = { 0 }, s2n_io_pair_close);
EXPECT_SUCCESS(s2n_io_pair_init_non_blocking(&io_pair));
EXPECT_SUCCESS(s2n_connections_set_io_pair(client, server, &io_pair));
EXPECT_ERROR_WITH_ERRNO(s2n_negotiate_test_server_and_client_until_message(server, client, SERVER_HELLO),
S2N_ERR_BAD_MESSAGE);
EXPECT_EQUAL(context.invoked_count, 1);
/* Ensure that a supported versions extension was received. */
bool supported_versions_received = false;
EXPECT_SUCCESS(s2n_client_hello_has_extension(&server->client_hello, S2N_EXTENSION_SUPPORTED_VERSIONS,
&supported_versions_received));
EXPECT_TRUE(supported_versions_received);
EXPECT_EQUAL(s2n_connection_get_server_protocol_version(server), S2N_TLS13);
EXPECT_EQUAL(s2n_connection_get_client_protocol_version(server), s2n_unknown_protocol_version);
EXPECT_EQUAL(s2n_connection_get_actual_protocol_version(server), s2n_unknown_protocol_version);
}
END_TEST();
}
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