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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_cipher_suites.h"
#include "tls/s2n_quic_support.h"
#include "tls/s2n_security_policies.h"
#include "tls/s2n_tls.h"
#include "tls/s2n_tls13.h"
#include "utils/s2n_safety.h"
const uint8_t SESSION_ID_SIZE = 1;
const uint8_t COMPRESSION_METHOD_SIZE = 1;
/* from RFC: https://tools.ietf.org/html/rfc8446#section-4.1.3*/
const char hello_retry_random_hex[] =
"CF21AD74E59A6111BE1D8C021E65B891"
"C2A211167ABB8C5E079E09E2C8A8339C";
const uint8_t tls12_downgrade_protection_check_bytes[] = {
0x44, 0x4F, 0x57, 0x4E, 0x47, 0x52, 0x44, 0x01
};
const uint8_t tls11_downgrade_protection_check_bytes[] = {
0x44, 0x4F, 0x57, 0x4E, 0x47, 0x52, 0x44, 0x00
};
static S2N_RESULT s2n_test_client_hello(struct s2n_connection *client_conn, struct s2n_connection *server_conn)
{
/* We have to "write" the handshake header for the PSK binder calculation, which expects a complete
* ClientHello message. We'll skip these bytes later.
*/
RESULT_GUARD_POSIX(s2n_stuffer_skip_write(&client_conn->handshake.io, TLS_HANDSHAKE_HEADER_LENGTH));
RESULT_GUARD_POSIX(s2n_client_hello_send(client_conn));
RESULT_GUARD_POSIX(s2n_stuffer_copy(&client_conn->handshake.io,
&server_conn->handshake.io, s2n_stuffer_data_available(&client_conn->handshake.io)));
/* Skip the handshake header bytes */
RESULT_GUARD_POSIX(s2n_stuffer_skip_read(&server_conn->handshake.io, TLS_HANDSHAKE_HEADER_LENGTH));
RESULT_GUARD_POSIX(s2n_client_hello_recv(server_conn));
RESULT_GUARD_POSIX(s2n_stuffer_wipe(&client_conn->handshake.io));
RESULT_GUARD_POSIX(s2n_stuffer_wipe(&server_conn->handshake.io));
return S2N_RESULT_OK;
}
int main(int argc, char **argv)
{
BEGIN_TEST();
EXPECT_SUCCESS(s2n_disable_tls13_in_test());
struct s2n_cert_chain_and_key *chain_and_key;
EXPECT_SUCCESS(s2n_test_cert_chain_and_key_new(&chain_and_key,
S2N_DEFAULT_ECDSA_TEST_CERT_CHAIN, S2N_DEFAULT_ECDSA_TEST_PRIVATE_KEY));
/* Test basic Server Hello Send */
{
struct s2n_config *config;
EXPECT_NOT_NULL(config = s2n_config_new());
struct s2n_connection *conn;
EXPECT_NOT_NULL(conn = s2n_connection_new(S2N_SERVER));
EXPECT_SUCCESS(s2n_connection_set_config(conn, config));
struct s2n_stuffer *hello_stuffer = &conn->handshake.io;
/* Test s2n_server_hello_send */
const uint32_t total = S2N_TLS_PROTOCOL_VERSION_LEN
+ S2N_TLS_RANDOM_DATA_LEN
+ SESSION_ID_SIZE
+ conn->session_id_len
+ S2N_TLS_CIPHER_SUITE_LEN
+ COMPRESSION_METHOD_SIZE;
conn->actual_protocol_version = S2N_TLS12;
EXPECT_SUCCESS(s2n_server_hello_send(conn));
EXPECT_EQUAL(hello_stuffer->blob.data[0], 0x03);
EXPECT_EQUAL(hello_stuffer->blob.data[1], 0x03);
S2N_STUFFER_LENGTH_WRITTEN_EXPECT_EQUAL(hello_stuffer, total);
EXPECT_SUCCESS(s2n_config_free(config));
EXPECT_SUCCESS(s2n_connection_free(conn));
};
/* Test that legacy_version_field is set correct for TLS 1.3 Server Hello Send */
{
EXPECT_SUCCESS(s2n_enable_tls13_in_test());
struct s2n_config *config = NULL;
const struct s2n_ecc_preferences *ecc_preferences = NULL;
EXPECT_NOT_NULL(config = s2n_config_new());
struct s2n_connection *conn = NULL;
EXPECT_NOT_NULL(conn = s2n_connection_new(S2N_SERVER));
EXPECT_SUCCESS(s2n_connection_set_config(conn, config));
EXPECT_NOT_NULL(conn->config);
EXPECT_SUCCESS(s2n_connection_get_ecc_preferences(conn, &ecc_preferences));
EXPECT_NOT_NULL(ecc_preferences);
/* configure these parameters so server hello can be sent */
conn->actual_protocol_version = S2N_TLS13;
conn->kex_params.server_ecc_evp_params.negotiated_curve = ecc_preferences->ecc_curves[0];
conn->kex_params.client_ecc_evp_params.negotiated_curve = ecc_preferences->ecc_curves[0];
EXPECT_SUCCESS(s2n_ecc_evp_generate_ephemeral_key(&conn->kex_params.client_ecc_evp_params));
struct s2n_stuffer *hello_stuffer = &conn->handshake.io;
EXPECT_SUCCESS(s2n_server_hello_send(conn));
/* verify that legacy protocol version is 0x0303 (TLS12) */
EXPECT_EQUAL(hello_stuffer->blob.data[0], 0x03);
EXPECT_EQUAL(hello_stuffer->blob.data[1], 0x03);
EXPECT_SUCCESS(s2n_config_free(config));
EXPECT_SUCCESS(s2n_connection_free(conn));
EXPECT_SUCCESS(s2n_disable_tls13_in_test());
};
/* Test basic Server Hello Recv */
{
struct s2n_config *server_config;
struct s2n_config *client_config;
struct s2n_connection *server_conn;
struct s2n_connection *client_conn;
EXPECT_NOT_NULL(server_config = s2n_config_new());
EXPECT_NOT_NULL(server_conn = s2n_connection_new(S2N_SERVER));
EXPECT_SUCCESS(s2n_connection_set_config(server_conn, server_config));
EXPECT_NOT_NULL(client_config = s2n_config_new());
EXPECT_NOT_NULL(client_conn = s2n_connection_new(S2N_CLIENT));
EXPECT_SUCCESS(s2n_connection_set_config(client_conn, client_config));
server_conn->actual_protocol_version = S2N_TLS12;
server_conn->secure->cipher_suite = &s2n_ecdhe_rsa_with_aes_256_gcm_sha384;
EXPECT_SUCCESS(s2n_server_hello_send(server_conn));
/* Copy server stuffer to client stuffer */
const uint32_t total = s2n_stuffer_data_available(&server_conn->handshake.io);
EXPECT_SUCCESS(s2n_stuffer_copy(&server_conn->handshake.io, &client_conn->handshake.io, total));
/* Test s2n_server_hello_recv() */
struct s2n_stuffer *client_stuffer = &client_conn->handshake.io;
EXPECT_SUCCESS(s2n_server_hello_recv(client_conn));
EXPECT_EQUAL(s2n_stuffer_data_available(client_stuffer), 0);
EXPECT_SUCCESS(s2n_config_free(client_config));
EXPECT_SUCCESS(s2n_config_free(server_config));
EXPECT_SUCCESS(s2n_connection_free(client_conn));
EXPECT_SUCCESS(s2n_connection_free(server_conn));
};
/* Test Server Hello Recv with invalid cipher */
{
struct s2n_connection *server_conn;
struct s2n_connection *client_conn;
EXPECT_NOT_NULL(server_conn = s2n_connection_new(S2N_SERVER));
EXPECT_NOT_NULL(client_conn = s2n_connection_new(S2N_CLIENT));
server_conn->actual_protocol_version = S2N_TLS12;
/* This cipher is not in the client's default selection */
server_conn->secure->cipher_suite = &s2n_tls13_chacha20_poly1305_sha256;
EXPECT_SUCCESS(s2n_server_hello_send(server_conn));
/* Copy server stuffer to client stuffer */
const uint32_t total = s2n_stuffer_data_available(&server_conn->handshake.io);
EXPECT_SUCCESS(s2n_stuffer_copy(&server_conn->handshake.io, &client_conn->handshake.io, total));
/* The client should fail the handshake because an invalid cipher was offered */
EXPECT_FAILURE_WITH_ERRNO(s2n_server_hello_recv(client_conn), S2N_ERR_CIPHER_NOT_SUPPORTED);
EXPECT_SUCCESS(s2n_connection_free(client_conn));
EXPECT_SUCCESS(s2n_connection_free(server_conn));
};
/* Non-matching session IDs turn off EMS for the connection */
{
struct s2n_connection *server_conn;
struct s2n_connection *client_conn;
EXPECT_NOT_NULL(server_conn = s2n_connection_new(S2N_SERVER));
EXPECT_NOT_NULL(client_conn = s2n_connection_new(S2N_CLIENT));
server_conn->actual_protocol_version = S2N_TLS12;
server_conn->secure->cipher_suite = &s2n_ecdhe_rsa_with_aes_256_gcm_sha384;
/* Create session ID for server */
for (int i = 0; i < 32; i++) {
server_conn->session_id[i] = i;
}
EXPECT_SUCCESS(s2n_server_hello_send(server_conn));
/* Copy server stuffer to client stuffer */
const uint32_t total = s2n_stuffer_data_available(&server_conn->handshake.io);
EXPECT_SUCCESS(s2n_stuffer_copy(&server_conn->handshake.io, &client_conn->handshake.io, total));
/* Create client session ID does not match server session ID */
for (int i = 0; i < 32; i++) {
client_conn->session_id[i] = 0;
}
/* Client is negotiating an EMS connection but is able to fallback to non-EMS connection
* if session IDs don't match */
client_conn->ems_negotiated = true;
EXPECT_SUCCESS(s2n_server_hello_recv(client_conn));
EXPECT_FALSE(client_conn->ems_negotiated);
EXPECT_SUCCESS(s2n_connection_free(client_conn));
EXPECT_SUCCESS(s2n_connection_free(server_conn));
};
/* Test TLS 1.3 session id matching */
{
EXPECT_SUCCESS(s2n_enable_tls13_in_test());
struct s2n_config *client_config;
struct s2n_connection *client_conn;
EXPECT_NOT_NULL(client_config = s2n_config_new());
EXPECT_NOT_NULL(client_conn = s2n_connection_new(S2N_CLIENT));
EXPECT_SUCCESS(s2n_connection_set_config(client_conn, client_config));
struct s2n_stuffer *io = &client_conn->handshake.io;
/* protocol version */
EXPECT_SUCCESS(s2n_stuffer_write_uint8(io, S2N_TLS12 / 10));
EXPECT_SUCCESS(s2n_stuffer_write_uint8(io, S2N_TLS12 % 10));
/* random payload */
uint8_t random[S2N_TLS_RANDOM_DATA_LEN] = { 0 };
EXPECT_SUCCESS(s2n_stuffer_write_bytes(io, random, S2N_TLS_RANDOM_DATA_LEN));
uint8_t session_id[S2N_TLS_SESSION_ID_MAX_LEN] = { 0 };
/* generate matching session id for payload and client connection */
for (int i = 0; i < 32; i++) {
session_id[i] = i;
client_conn->session_id[i] = i;
}
/* session id */
EXPECT_SUCCESS(s2n_stuffer_write_uint8(io, S2N_TLS_SESSION_ID_MAX_LEN));
EXPECT_SUCCESS(s2n_stuffer_write_bytes(io, session_id, S2N_TLS_SESSION_ID_MAX_LEN));
EXPECT_SUCCESS(s2n_stuffer_write_uint16(io, (0x13 << 8) + 0x01)); /* cipher suites */
EXPECT_SUCCESS(s2n_stuffer_write_uint8(io, 0)); /* no compression */
client_conn->server_protocol_version = S2N_TLS13;
client_conn->session_id_len = 32;
/* Test s2n_server_hello_recv() */
EXPECT_SUCCESS(s2n_server_hello_recv(client_conn));
EXPECT_EQUAL(s2n_stuffer_data_available(io), 0);
/* Check that corrupt session id fails server hello */
for (int i = 0; i < 32; i++) {
client_conn->session_id[i] ^= 1;
EXPECT_SUCCESS(s2n_stuffer_reread(io));
EXPECT_FAILURE(s2n_server_hello_recv(client_conn));
client_conn->session_id[i] ^= 1;
}
/* Check that server hello is successful again */
EXPECT_SUCCESS(s2n_stuffer_reread(io));
EXPECT_SUCCESS(s2n_server_hello_recv(client_conn));
/* Check that unmatched session length should also fail */
for (int i = 0; i < 32; i++) {
client_conn->session_id_len = i;
EXPECT_SUCCESS(s2n_stuffer_reread(io));
EXPECT_FAILURE(s2n_server_hello_recv(client_conn));
}
EXPECT_SUCCESS(s2n_config_free(client_config));
EXPECT_SUCCESS(s2n_connection_free(client_conn));
EXPECT_SUCCESS(s2n_disable_tls13_in_test());
};
/* Test TLS 1.3 => 1.1 protocol downgrade detection with a TLS1.3 client */
{
EXPECT_SUCCESS(s2n_enable_tls13_in_test());
struct s2n_config *client_config;
struct s2n_connection *client_conn;
struct s2n_config *server_config;
struct s2n_connection *server_conn;
EXPECT_NOT_NULL(server_config = s2n_config_new());
EXPECT_NOT_NULL(server_conn = s2n_connection_new(S2N_SERVER));
EXPECT_SUCCESS(s2n_connection_set_config(server_conn, server_config));
EXPECT_NOT_NULL(client_config = s2n_config_new());
EXPECT_NOT_NULL(client_conn = s2n_connection_new(S2N_CLIENT));
EXPECT_SUCCESS(s2n_connection_set_config(client_conn, client_config));
/* The client will request TLS1.3 */
client_conn->client_protocol_version = S2N_TLS13;
/* Set the negotiated curve, otherwise the server might try to respond with a retry */
server_conn->kex_params.server_ecc_evp_params.negotiated_curve = s2n_all_supported_curves_list[0];
/* The server will respond with TLS1.1 even though it supports TLS1.3 */
server_conn->actual_protocol_version = S2N_TLS11;
EXPECT_SUCCESS(s2n_server_hello_send(server_conn));
/* Copy server stuffer to client stuffer */
const uint32_t total = s2n_stuffer_data_available(&server_conn->handshake.io);
EXPECT_SUCCESS(s2n_stuffer_copy(&server_conn->handshake.io, &client_conn->handshake.io, total));
/* Verify that the downgrade is detected */
struct s2n_stuffer *client_stuffer = &client_conn->handshake.io;
EXPECT_BYTEARRAY_EQUAL(&client_stuffer->blob.data[S2N_TLS_PROTOCOL_VERSION_LEN + 24], tls11_downgrade_protection_check_bytes, 8);
EXPECT_FAILURE_WITH_ERRNO(s2n_server_hello_recv(client_conn), S2N_ERR_PROTOCOL_DOWNGRADE_DETECTED);
EXPECT_EQUAL(s2n_stuffer_data_available(client_stuffer), 0);
EXPECT_SUCCESS(s2n_config_free(client_config));
EXPECT_SUCCESS(s2n_config_free(server_config));
EXPECT_SUCCESS(s2n_connection_free(client_conn));
EXPECT_SUCCESS(s2n_connection_free(server_conn));
EXPECT_SUCCESS(s2n_disable_tls13_in_test());
};
/* Test TLS 1.3 => 1.2 protocol downgrade detection with a TLS1.3 client */
{
EXPECT_SUCCESS(s2n_enable_tls13_in_test());
struct s2n_config *client_config;
struct s2n_connection *client_conn;
struct s2n_config *server_config;
struct s2n_connection *server_conn;
EXPECT_NOT_NULL(server_config = s2n_config_new());
EXPECT_NOT_NULL(server_conn = s2n_connection_new(S2N_SERVER));
EXPECT_SUCCESS(s2n_connection_set_config(server_conn, server_config));
EXPECT_NOT_NULL(client_config = s2n_config_new());
EXPECT_NOT_NULL(client_conn = s2n_connection_new(S2N_CLIENT));
EXPECT_SUCCESS(s2n_connection_set_config(client_conn, client_config));
/* The client will request TLS1.3 */
client_conn->client_protocol_version = S2N_TLS13;
/* Set the negotiated curve, otherwise the server might try to respond with a retry */
server_conn->kex_params.server_ecc_evp_params.negotiated_curve = s2n_all_supported_curves_list[0];
/* The server will respond with TLS1.2 even though it supports TLS1.3 */
server_conn->actual_protocol_version = S2N_TLS12;
EXPECT_SUCCESS(s2n_server_hello_send(server_conn));
/* Copy server stuffer to client stuffer */
const uint32_t total = s2n_stuffer_data_available(&server_conn->handshake.io);
EXPECT_SUCCESS(s2n_stuffer_copy(&server_conn->handshake.io, &client_conn->handshake.io, total));
/* Verify that the downgrade is detected */
struct s2n_stuffer *client_stuffer = &client_conn->handshake.io;
EXPECT_BYTEARRAY_EQUAL(&client_stuffer->blob.data[S2N_TLS_PROTOCOL_VERSION_LEN + 24], tls12_downgrade_protection_check_bytes, 8);
EXPECT_FAILURE_WITH_ERRNO(s2n_server_hello_recv(client_conn), S2N_ERR_PROTOCOL_DOWNGRADE_DETECTED);
EXPECT_EQUAL(s2n_stuffer_data_available(client_stuffer), 0);
EXPECT_SUCCESS(s2n_config_free(client_config));
EXPECT_SUCCESS(s2n_config_free(server_config));
EXPECT_SUCCESS(s2n_connection_free(client_conn));
EXPECT_SUCCESS(s2n_connection_free(server_conn));
EXPECT_SUCCESS(s2n_disable_tls13_in_test());
};
/* Verify a TLS1.2 client can negotiate with a TLS1.3 server */
{
struct s2n_config *client_config;
struct s2n_connection *client_conn;
struct s2n_config *server_config;
struct s2n_connection *server_conn;
EXPECT_NOT_NULL(server_config = s2n_config_new());
EXPECT_NOT_NULL(server_conn = s2n_connection_new(S2N_SERVER));
EXPECT_SUCCESS(s2n_connection_set_config(server_conn, server_config));
EXPECT_NOT_NULL(client_config = s2n_config_new());
EXPECT_NOT_NULL(client_conn = s2n_connection_new(S2N_CLIENT));
EXPECT_SUCCESS(s2n_connection_set_config(client_conn, client_config));
/* The client will request TLS1.2 */
client_conn->client_protocol_version = S2N_TLS12;
/* The server will respond with TLS1.2 even though it support TLS1.3. This is expected because */
/* the client only support TLS1.2 */
EXPECT_SUCCESS(s2n_enable_tls13_in_test());
server_conn->actual_protocol_version = S2N_TLS12;
server_conn->secure->cipher_suite = &s2n_ecdhe_rsa_with_aes_256_gcm_sha384;
EXPECT_SUCCESS(s2n_server_hello_send(server_conn));
EXPECT_SUCCESS(s2n_disable_tls13_in_test());
/* Copy server stuffer to client stuffer */
const uint32_t total = s2n_stuffer_data_available(&server_conn->handshake.io);
EXPECT_SUCCESS(s2n_stuffer_copy(&server_conn->handshake.io, &client_conn->handshake.io, total));
/* Verify that a TLS12 client does not error due to the downgrade */
struct s2n_stuffer *client_stuffer = &client_conn->handshake.io;
EXPECT_SUCCESS(s2n_server_hello_recv(client_conn));
EXPECT_EQUAL(s2n_stuffer_data_available(client_stuffer), 0);
EXPECT_SUCCESS(s2n_config_free(client_config));
EXPECT_SUCCESS(s2n_config_free(server_config));
EXPECT_SUCCESS(s2n_connection_free(client_conn));
EXPECT_SUCCESS(s2n_connection_free(server_conn));
};
/* Verify a TLS1.3 client can negotiate with a TLS1.2 server */
{
struct s2n_config *client_config;
struct s2n_connection *client_conn;
struct s2n_config *server_config;
struct s2n_connection *server_conn;
EXPECT_NOT_NULL(server_config = s2n_config_new());
EXPECT_NOT_NULL(server_conn = s2n_connection_new(S2N_SERVER));
EXPECT_SUCCESS(s2n_connection_set_config(server_conn, server_config));
EXPECT_NOT_NULL(client_config = s2n_config_new());
EXPECT_NOT_NULL(client_conn = s2n_connection_new(S2N_CLIENT));
EXPECT_SUCCESS(s2n_connection_set_config(client_conn, client_config));
/* The client will request TLS1.3 */
client_conn->client_protocol_version = S2N_TLS13;
/* The server will respond with TLS1.2 */
server_conn->server_protocol_version = S2N_TLS12;
server_conn->actual_protocol_version = S2N_TLS12;
server_conn->secure->cipher_suite = &s2n_ecdhe_rsa_with_aes_256_gcm_sha384;
EXPECT_SUCCESS(s2n_server_hello_send(server_conn));
/* Copy server stuffer to client stuffer */
const uint32_t total = s2n_stuffer_data_available(&server_conn->handshake.io);
EXPECT_SUCCESS(s2n_stuffer_copy(&server_conn->handshake.io, &client_conn->handshake.io, total));
/* Verify that a TLS13 client does not error due to the downgrade */
struct s2n_stuffer *client_stuffer = &client_conn->handshake.io;
POSIX_GUARD(s2n_enable_tls13_in_test());
EXPECT_SUCCESS(s2n_server_hello_recv(client_conn));
POSIX_GUARD(s2n_disable_tls13_in_test());
EXPECT_EQUAL(s2n_stuffer_data_available(client_stuffer), 0);
EXPECT_SUCCESS(s2n_config_free(client_config));
EXPECT_SUCCESS(s2n_config_free(server_config));
EXPECT_SUCCESS(s2n_connection_free(client_conn));
EXPECT_SUCCESS(s2n_connection_free(server_conn));
};
/* Verify a TLS1.2 client can negotiate with a TLS1.3 server */
{
struct s2n_config *client_config;
struct s2n_connection *client_conn;
struct s2n_config *server_config;
struct s2n_connection *server_conn;
EXPECT_NOT_NULL(server_config = s2n_config_new());
EXPECT_NOT_NULL(server_conn = s2n_connection_new(S2N_SERVER));
EXPECT_SUCCESS(s2n_connection_set_config(server_conn, server_config));
EXPECT_NOT_NULL(client_config = s2n_config_new());
EXPECT_NOT_NULL(client_conn = s2n_connection_new(S2N_CLIENT));
EXPECT_SUCCESS(s2n_connection_set_config(client_conn, client_config));
/* The client will request TLS1.2 */
client_conn->client_protocol_version = S2N_TLS12;
/* The server will respond with TLS1.2 even though it support TLS1.3. This is expected because */
/* the client only support TLS1.2 */
EXPECT_SUCCESS(s2n_enable_tls13_in_test());
server_conn->actual_protocol_version = S2N_TLS12;
server_conn->secure->cipher_suite = &s2n_ecdhe_rsa_with_aes_256_gcm_sha384;
EXPECT_SUCCESS(s2n_server_hello_send(server_conn));
EXPECT_SUCCESS(s2n_disable_tls13_in_test());
/* Copy server stuffer to client stuffer */
const uint32_t total = s2n_stuffer_data_available(&server_conn->handshake.io);
EXPECT_SUCCESS(s2n_stuffer_copy(&server_conn->handshake.io, &client_conn->handshake.io, total));
/* Verify that a TLS12 client does not error due to the downgrade */
struct s2n_stuffer *client_stuffer = &client_conn->handshake.io;
EXPECT_SUCCESS(s2n_server_hello_recv(client_conn));
EXPECT_EQUAL(s2n_stuffer_data_available(client_stuffer), 0);
EXPECT_SUCCESS(s2n_config_free(client_config));
EXPECT_SUCCESS(s2n_config_free(server_config));
EXPECT_SUCCESS(s2n_connection_free(client_conn));
EXPECT_SUCCESS(s2n_connection_free(server_conn));
};
/* TLS13 hello retry message received results into S2N_ERR_UNIMPLEMENTED error*/
{
struct s2n_connection *client_conn;
EXPECT_NOT_NULL(client_conn = s2n_connection_new(S2N_CLIENT));
struct s2n_stuffer *io = &client_conn->handshake.io;
client_conn->server_protocol_version = S2N_TLS13;
/* protocol version */
EXPECT_SUCCESS(s2n_stuffer_write_uint8(io, S2N_TLS12 / 10));
EXPECT_SUCCESS(s2n_stuffer_write_uint8(io, S2N_TLS12 % 10));
uint8_t session_id[S2N_TLS_SESSION_ID_MAX_LEN] = { 0 };
S2N_BLOB_FROM_HEX(random_blob, hello_retry_random_hex);
/* random payload */
EXPECT_SUCCESS(s2n_stuffer_write_bytes(io, random_blob.data, S2N_TLS_RANDOM_DATA_LEN));
/* session id */
EXPECT_SUCCESS(s2n_stuffer_write_uint8(io, S2N_TLS_SESSION_ID_MAX_LEN));
EXPECT_SUCCESS(s2n_stuffer_write_bytes(io, session_id, S2N_TLS_SESSION_ID_MAX_LEN));
/* cipher suites */
EXPECT_SUCCESS(s2n_stuffer_write_uint16(io, (0x13 << 8) + 0x01));
/* no compression */
EXPECT_SUCCESS(s2n_stuffer_write_uint8(io, 0));
EXPECT_EQUAL(S2N_TLS_RANDOM_DATA_LEN, random_blob.size);
EXPECT_SUCCESS(s2n_connection_free(client_conn));
};
/* Test that negotiating TLS1.2 with QUIC-enabled client fails */
if (s2n_is_tls13_fully_supported()) {
EXPECT_SUCCESS(s2n_reset_tls13_in_test());
struct s2n_config *quic_config = s2n_config_new();
EXPECT_SUCCESS(s2n_config_set_cipher_preferences(quic_config, "test_all"));
EXPECT_SUCCESS(s2n_config_add_cert_chain_and_key_to_store(quic_config, chain_and_key));
EXPECT_SUCCESS(s2n_config_enable_quic(quic_config));
struct s2n_config *non_quic_config = s2n_config_new();
EXPECT_SUCCESS(s2n_config_set_cipher_preferences(non_quic_config, "test_all"));
EXPECT_SUCCESS(s2n_config_add_cert_chain_and_key_to_store(non_quic_config, chain_and_key));
/* Succeeds when negotiating TLS1.3 */
if (s2n_is_tls13_fully_supported()) {
struct s2n_connection *client_conn = s2n_connection_new(S2N_CLIENT);
EXPECT_SUCCESS(s2n_connection_set_config(client_conn, non_quic_config));
struct s2n_connection *server_conn = s2n_connection_new(S2N_SERVER);
EXPECT_SUCCESS(s2n_connection_set_config(server_conn, non_quic_config));
EXPECT_OK(s2n_test_client_hello(client_conn, server_conn));
EXPECT_SUCCESS(s2n_connection_set_config(client_conn, quic_config));
EXPECT_SUCCESS(s2n_server_hello_send(server_conn));
EXPECT_SUCCESS(s2n_stuffer_copy(&server_conn->handshake.io,
&client_conn->handshake.io, s2n_stuffer_data_available(&server_conn->handshake.io)));
EXPECT_SUCCESS(s2n_server_hello_recv(client_conn));
EXPECT_EQUAL(client_conn->actual_protocol_version, S2N_TLS13);
EXPECT_EQUAL(server_conn->actual_protocol_version, S2N_TLS13);
EXPECT_SUCCESS(s2n_connection_free(client_conn));
EXPECT_SUCCESS(s2n_connection_free(server_conn));
}
/* Fails when negotiating TLS1.2 */
{
struct s2n_connection *server_conn = s2n_connection_new(S2N_SERVER);
EXPECT_SUCCESS(s2n_connection_set_config(server_conn, non_quic_config));
EXPECT_SUCCESS(s2n_connection_set_cipher_preferences(server_conn, "test_all_tls12"));
struct s2n_connection *client_conn = s2n_connection_new(S2N_CLIENT);
EXPECT_SUCCESS(s2n_connection_set_config(client_conn, non_quic_config));
EXPECT_OK(s2n_test_client_hello(client_conn, server_conn));
EXPECT_SUCCESS(s2n_connection_set_config(client_conn, quic_config));
EXPECT_SUCCESS(s2n_server_hello_send(server_conn));
EXPECT_SUCCESS(s2n_stuffer_copy(&server_conn->handshake.io,
&client_conn->handshake.io, s2n_stuffer_data_available(&server_conn->handshake.io)));
EXPECT_FAILURE_WITH_ERRNO(s2n_server_hello_recv(client_conn), S2N_ERR_PROTOCOL_VERSION_UNSUPPORTED);
EXPECT_EQUAL(server_conn->actual_protocol_version, S2N_TLS12);
EXPECT_SUCCESS(s2n_connection_free(client_conn));
EXPECT_SUCCESS(s2n_connection_free(server_conn));
};
EXPECT_SUCCESS(s2n_config_free(quic_config));
EXPECT_SUCCESS(s2n_config_free(non_quic_config));
}
/* Test that negotiating TLS1.2 with an early data enabled client fails.
*
*= https://tools.ietf.org/rfc/rfc8446#appendix-D.3
*= type=test
*# A client that attempts to send 0-RTT data MUST fail a connection if
*# it receives a ServerHello with TLS 1.2 or older.
*/
if (s2n_is_tls13_fully_supported()) {
EXPECT_SUCCESS(s2n_reset_tls13_in_test());
struct s2n_config *config = s2n_config_new();
EXPECT_SUCCESS(s2n_config_add_cert_chain_and_key_to_store(config, chain_and_key));
/* Succeeds when negotiating TLS1.3 */
{
struct s2n_connection *client_conn = s2n_connection_new(S2N_CLIENT);
EXPECT_SUCCESS(s2n_connection_set_config(client_conn, config));
EXPECT_SUCCESS(s2n_connection_set_cipher_preferences(client_conn, "test_all"));
EXPECT_OK(s2n_append_test_psk_with_early_data(client_conn, 1, &s2n_tls13_aes_128_gcm_sha256));
EXPECT_SUCCESS(s2n_connection_set_early_data_expected(client_conn));
struct s2n_connection *server_conn = s2n_connection_new(S2N_SERVER);
EXPECT_SUCCESS(s2n_connection_set_config(server_conn, config));
EXPECT_SUCCESS(s2n_connection_set_cipher_preferences(server_conn, "test_all"));
EXPECT_OK(s2n_append_test_psk_with_early_data(server_conn, 1, &s2n_tls13_aes_128_gcm_sha256));
EXPECT_SUCCESS(s2n_connection_set_early_data_expected(server_conn));
EXPECT_OK(s2n_test_client_hello(client_conn, server_conn));
EXPECT_SUCCESS(s2n_server_hello_send(server_conn));
EXPECT_SUCCESS(s2n_stuffer_copy(&server_conn->handshake.io,
&client_conn->handshake.io, s2n_stuffer_data_available(&server_conn->handshake.io)));
EXPECT_SUCCESS(s2n_server_hello_recv(client_conn));
EXPECT_EQUAL(client_conn->early_data_state, S2N_EARLY_DATA_REQUESTED);
EXPECT_EQUAL(client_conn->server_protocol_version, S2N_TLS13);
EXPECT_EQUAL(server_conn->actual_protocol_version, S2N_TLS13);
EXPECT_SUCCESS(s2n_connection_free(client_conn));
EXPECT_SUCCESS(s2n_connection_free(server_conn));
};
/* TLS 1.3 Client Early Data is rejected when server only supports TLS1.2 */
{
struct s2n_connection *client_conn = s2n_connection_new(S2N_CLIENT);
EXPECT_SUCCESS(s2n_connection_set_config(client_conn, config));
EXPECT_SUCCESS(s2n_connection_set_cipher_preferences(client_conn, "test_all"));
EXPECT_OK(s2n_append_test_psk_with_early_data(client_conn, 1, &s2n_tls13_aes_128_gcm_sha256));
EXPECT_SUCCESS(s2n_connection_set_early_data_expected(client_conn));
struct s2n_connection *server_conn = s2n_connection_new(S2N_SERVER);
EXPECT_SUCCESS(s2n_connection_set_config(server_conn, config));
EXPECT_SUCCESS(s2n_connection_set_cipher_preferences(server_conn, "test_all_tls12"));
EXPECT_OK(s2n_append_test_psk_with_early_data(server_conn, 1, &s2n_tls13_aes_128_gcm_sha256));
EXPECT_SUCCESS(s2n_connection_set_early_data_expected(server_conn));
EXPECT_OK(s2n_test_client_hello(client_conn, server_conn));
EXPECT_SUCCESS(s2n_server_hello_send(server_conn));
EXPECT_SUCCESS(s2n_stuffer_copy(&server_conn->handshake.io,
&client_conn->handshake.io, s2n_stuffer_data_available(&server_conn->handshake.io)));
EXPECT_FAILURE_WITH_ERRNO(s2n_server_hello_recv(client_conn), S2N_ERR_PROTOCOL_VERSION_UNSUPPORTED);
EXPECT_EQUAL(client_conn->early_data_state, S2N_EARLY_DATA_REQUESTED);
EXPECT_EQUAL(client_conn->server_protocol_version, S2N_TLS12);
EXPECT_EQUAL(server_conn->actual_protocol_version, S2N_TLS12);
EXPECT_SUCCESS(s2n_connection_free(client_conn));
EXPECT_SUCCESS(s2n_connection_free(server_conn));
};
EXPECT_SUCCESS(s2n_config_free(config));
EXPECT_SUCCESS(s2n_disable_tls13_in_test());
}
EXPECT_SUCCESS(s2n_cert_chain_and_key_free(chain_and_key));
END_TEST();
}
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