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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 <stdint.h>
#include "s2n_test.h"
#include "stuffer/s2n_stuffer.h"
#include "testlib/s2n_testlib.h"
#include "tls/extensions/s2n_client_key_share.h"
#include "tls/extensions/s2n_key_share.h"
#include "tls/s2n_alerts.h"
#include "tls/s2n_config.h"
#include "tls/s2n_connection.h"
#include "tls/s2n_security_policies.h"
#include "tls/s2n_tls.h"
#include "tls/s2n_tls13.h"
#include "utils/s2n_safety.h"
#define HELLO_RETRY_MSG_NO 1
#define S2N_SIZE_OF_CLIENT_SHARE_SIZE 2
#define S2N_PREPARE_DATA_LENGTH(stuffer) \
EXPECT_SUCCESS(s2n_stuffer_skip_write(stuffer, S2N_SIZE_OF_CLIENT_SHARE_SIZE))
#define S2N_WRITE_DATA_LENGTH(stuffer) \
EXPECT_SUCCESS(s2n_test_rewrite_length(stuffer))
static int s2n_test_rewrite_length(struct s2n_stuffer *stuffer);
static int s2n_write_named_curve(struct s2n_stuffer *out, const struct s2n_ecc_named_curve *existing_curve);
static int s2n_write_key_share(struct s2n_stuffer *out, uint16_t iana_value, uint16_t share_size,
const struct s2n_ecc_named_curve *existing_curve);
S2N_RESULT s2n_extensions_client_key_share_size(struct s2n_connection *conn, uint32_t *size)
{
RESULT_ENSURE_REF(conn);
const struct s2n_ecc_preferences *ecc_pref = NULL;
RESULT_GUARD_POSIX(s2n_connection_get_ecc_preferences(conn, &ecc_pref));
RESULT_ENSURE_REF(ecc_pref);
uint32_t s2n_client_key_share_extension_size = S2N_SIZE_OF_EXTENSION_TYPE
+ S2N_SIZE_OF_EXTENSION_DATA_SIZE
+ S2N_SIZE_OF_CLIENT_SHARES_SIZE;
s2n_client_key_share_extension_size += S2N_SIZE_OF_KEY_SHARE_SIZE + S2N_SIZE_OF_NAMED_GROUP;
s2n_client_key_share_extension_size += ecc_pref->ecc_curves[0]->share_size;
*size = s2n_client_key_share_extension_size;
return S2N_RESULT_OK;
}
int main(int argc, char **argv)
{
BEGIN_TEST();
EXPECT_SUCCESS(s2n_enable_tls13_in_test());
/* Test that s2n_extensions_key_share_size produces the expected constant result */
{
struct s2n_stuffer key_share_extension = { 0 };
struct s2n_connection *conn;
EXPECT_NOT_NULL(conn = s2n_connection_new(S2N_CLIENT));
uint32_t key_share_size = 0;
EXPECT_OK(s2n_extensions_client_key_share_size(conn, &key_share_size));
/* should produce the same result if called twice */
uint32_t key_share_size_again = 0;
EXPECT_OK(s2n_extensions_client_key_share_size(conn, &key_share_size_again));
EXPECT_EQUAL(key_share_size, key_share_size_again);
/* should equal the size of the data written on send */
EXPECT_SUCCESS(s2n_stuffer_alloc(&key_share_extension, key_share_size));
EXPECT_SUCCESS(s2n_client_key_share_extension.send(conn, &key_share_extension));
EXPECT_EQUAL(key_share_size - S2N_EXTENSION_TYPE_FIELD_LENGTH - S2N_EXTENSION_LENGTH_FIELD_LENGTH,
s2n_stuffer_data_available(&key_share_extension));
EXPECT_SUCCESS(s2n_stuffer_free(&key_share_extension));
EXPECT_SUCCESS(s2n_connection_free(conn));
};
/* Test s2n_client_key_share_extension.send */
{
/* Test that s2n_client_key_share_extension.send initializes the client key share list */
{
struct s2n_stuffer key_share_extension = { 0 };
struct s2n_connection *conn;
EXPECT_NOT_NULL(conn = s2n_connection_new(S2N_CLIENT));
EXPECT_SUCCESS(s2n_stuffer_growable_alloc(&key_share_extension, 0));
EXPECT_SUCCESS(s2n_client_key_share_extension.send(conn, &key_share_extension));
const struct s2n_ecc_preferences *ecc_preferences = NULL;
EXPECT_SUCCESS(s2n_connection_get_ecc_preferences(conn, &ecc_preferences));
EXPECT_NOT_NULL(ecc_preferences);
struct s2n_ecc_evp_params *ecc_evp_params = &conn->kex_params.client_ecc_evp_params;
EXPECT_EQUAL(ecc_evp_params->negotiated_curve, ecc_preferences->ecc_curves[0]);
EXPECT_NOT_NULL(ecc_evp_params->evp_pkey);
EXPECT_SUCCESS(s2n_stuffer_free(&key_share_extension));
EXPECT_SUCCESS(s2n_connection_free(conn));
};
/* Test that s2n_client_key_share_extension.send writes a well-formed list of key shares */
{
struct s2n_stuffer key_share_extension = { 0 };
struct s2n_connection *conn;
EXPECT_NOT_NULL(conn = s2n_connection_new(S2N_CLIENT));
EXPECT_SUCCESS(s2n_stuffer_growable_alloc(&key_share_extension, 0));
EXPECT_SUCCESS(s2n_client_key_share_extension.send(conn, &key_share_extension));
/* should have correct shares size */
uint16_t key_shares_size;
EXPECT_SUCCESS(s2n_stuffer_read_uint16(&key_share_extension, &key_shares_size));
uint16_t actual_key_shares_size = s2n_stuffer_data_available(&key_share_extension);
EXPECT_EQUAL(key_shares_size, actual_key_shares_size);
EXPECT_EQUAL(key_shares_size, s2n_stuffer_data_available(&key_share_extension));
const struct s2n_ecc_preferences *ecc_preferences = NULL;
EXPECT_SUCCESS(s2n_connection_get_ecc_preferences(conn, &ecc_preferences));
EXPECT_NOT_NULL(ecc_preferences);
/* should contain only the default supported curve */
uint16_t iana_value, share_size;
EXPECT_SUCCESS(s2n_stuffer_read_uint16(&key_share_extension, &iana_value));
EXPECT_EQUAL(iana_value, ecc_preferences->ecc_curves[0]->iana_id);
EXPECT_SUCCESS(s2n_stuffer_read_uint16(&key_share_extension, &share_size));
EXPECT_EQUAL(share_size, ecc_preferences->ecc_curves[0]->share_size);
EXPECT_SUCCESS(s2n_stuffer_skip_read(&key_share_extension, share_size));
EXPECT_SUCCESS(s2n_stuffer_free(&key_share_extension));
EXPECT_SUCCESS(s2n_connection_free(conn));
};
/* Test s2n_client_key_share_extension.send for a supported curve present in s2n_all_supported_curves_list,
* but not present in the ecc_preferences list selected */
if (s2n_is_evp_apis_supported()) {
struct s2n_stuffer key_share_extension = { 0 };
struct s2n_connection *conn;
struct s2n_config *config;
EXPECT_NOT_NULL(config = s2n_config_new());
EXPECT_NOT_NULL(conn = s2n_connection_new(S2N_CLIENT));
/* Explicitly set the ecc_preferences list to contain the curves p-256 and p-384 */
EXPECT_SUCCESS(s2n_config_set_cipher_preferences(config, "20140601"));
EXPECT_SUCCESS(s2n_connection_set_config(conn, config));
const struct s2n_ecc_preferences *ecc_preferences = NULL;
EXPECT_SUCCESS(s2n_connection_get_ecc_preferences(conn, &ecc_preferences));
EXPECT_NOT_NULL(ecc_preferences);
/* x25519 is present in s2n_all_supported_curves_list but not in the "default" list */
const struct s2n_ecc_named_curve *test_curve = &s2n_ecc_curve_x25519;
EXPECT_SUCCESS(s2n_stuffer_growable_alloc(&key_share_extension, 0));
EXPECT_SUCCESS(s2n_client_key_share_extension.send(conn, &key_share_extension));
struct s2n_ecc_evp_params *ecc_evp_params = &conn->kex_params.client_ecc_evp_params;
EXPECT_NOT_EQUAL(ecc_evp_params->negotiated_curve, test_curve);
EXPECT_SUCCESS(s2n_stuffer_free(&key_share_extension));
EXPECT_SUCCESS(s2n_connection_free(conn));
EXPECT_SUCCESS(s2n_config_free(config));
}
};
/* Test s2n_client_key_share_extension.send with HelloRetryRequest */
{
/**
* For HelloRetryRequests when a keyshare does not match, test that s2n_client_key_share_extension.send replaces
* the list of keyshares with a list containing a single KeyShareEntry for the server selected group.
*
*= https://tools.ietf.org/rfc/rfc8446#4.1.2
*= type=test
*# - If a "key_share" extension was supplied in the HelloRetryRequest,
*# replacing the list of shares with a list containing a single
*# KeyShareEntry from the indicated group.
*
*= https://tools.ietf.org/rfc/rfc8446#4.2.8
*= type=test
*# Otherwise, when sending the new ClientHello, the client MUST
*# replace the original "key_share" extension with one containing only a
*# new KeyShareEntry for the group indicated in the selected_group field
*# of the triggering HelloRetryRequest.
**/
if (s2n_is_evp_apis_supported()) {
struct s2n_connection *conn;
struct s2n_config *config;
struct s2n_stuffer key_share_extension = { 0 };
EXPECT_NOT_NULL(config = s2n_config_new());
EXPECT_NOT_NULL(conn = s2n_connection_new(S2N_CLIENT));
/* Security policy "20190801" contains x25519 */
EXPECT_SUCCESS(s2n_config_set_cipher_preferences(config, "20190801"));
EXPECT_SUCCESS(s2n_connection_set_config(conn, config));
EXPECT_SUCCESS(s2n_stuffer_growable_alloc(&key_share_extension, 0));
/* Force the client to send an unsupported curve in keyshare list */
conn->security_policy_override = &security_policy_test_tls13_retry;
const struct s2n_ecc_preferences *ecc_preferences = NULL;
EXPECT_SUCCESS(s2n_connection_get_ecc_preferences(conn, &ecc_preferences));
EXPECT_NOT_NULL(ecc_preferences);
EXPECT_SUCCESS(s2n_client_key_share_extension.send(conn, &key_share_extension));
/* Setup the client to have received a HelloRetryRequest with server negotiated curve as x25519 */
EXPECT_MEMCPY_SUCCESS(conn->handshake_params.server_random, hello_retry_req_random, S2N_TLS_RANDOM_DATA_LEN);
EXPECT_SUCCESS(s2n_connection_set_all_protocol_versions(conn, S2N_TLS13));
EXPECT_SUCCESS(s2n_set_connection_hello_retry_flags(conn));
conn->kex_params.server_ecc_evp_params.negotiated_curve = &s2n_ecc_curve_x25519;
EXPECT_SUCCESS(s2n_stuffer_free(&key_share_extension));
EXPECT_SUCCESS(s2n_stuffer_growable_alloc(&key_share_extension, 0));
EXPECT_SUCCESS(s2n_client_key_share_extension.send(conn, &key_share_extension));
uint16_t key_shares_size;
EXPECT_SUCCESS(s2n_stuffer_read_uint16(&key_share_extension, &key_shares_size));
EXPECT_EQUAL(s2n_stuffer_data_available(&key_share_extension), key_shares_size);
/* should contain keyshare for only server negotiated curve */
uint32_t bytes_processed = 0;
EXPECT_EQUAL(key_shares_size, conn->kex_params.server_ecc_evp_params.negotiated_curve->share_size + S2N_SIZE_OF_NAMED_GROUP + S2N_SIZE_OF_KEY_SHARE_SIZE);
uint16_t iana_value, share_size;
EXPECT_SUCCESS(s2n_stuffer_read_uint16(&key_share_extension, &iana_value));
EXPECT_SUCCESS(s2n_stuffer_read_uint16(&key_share_extension, &share_size));
bytes_processed += conn->kex_params.server_ecc_evp_params.negotiated_curve->share_size + S2N_SIZE_OF_NAMED_GROUP
+ S2N_SIZE_OF_KEY_SHARE_SIZE;
EXPECT_EQUAL(iana_value, conn->kex_params.server_ecc_evp_params.negotiated_curve->iana_id);
EXPECT_EQUAL(share_size, conn->kex_params.server_ecc_evp_params.negotiated_curve->share_size);
EXPECT_SUCCESS(s2n_stuffer_skip_read(&key_share_extension, share_size));
EXPECT_EQUAL(bytes_processed, key_shares_size);
EXPECT_SUCCESS(s2n_stuffer_free(&key_share_extension));
EXPECT_SUCCESS(s2n_config_free(config));
EXPECT_SUCCESS(s2n_connection_free(conn));
}
/* For HelloRetryRequests, test that s2n_client_key_share_extension.recv can read and parse
* the result of s2n_client_key_share_extension.send */
{
struct s2n_connection *client_conn;
struct s2n_connection *server_conn;
struct s2n_stuffer key_share_extension = { 0 };
EXPECT_NOT_NULL(client_conn = s2n_connection_new(S2N_CLIENT));
EXPECT_NOT_NULL(server_conn = s2n_connection_new(S2N_SERVER));
EXPECT_OK(s2n_set_all_mutually_supported_groups(server_conn));
EXPECT_SUCCESS(s2n_stuffer_growable_alloc(&key_share_extension, 0));
const struct s2n_ecc_preferences *ecc_preferences = NULL;
EXPECT_SUCCESS(s2n_connection_get_ecc_preferences(server_conn, &ecc_preferences));
EXPECT_NOT_NULL(ecc_preferences);
/* Setup the client to have received a HelloRetryRequest */
POSIX_CHECKED_MEMCPY(client_conn->handshake_params.server_random, hello_retry_req_random, S2N_TLS_RANDOM_DATA_LEN);
EXPECT_SUCCESS(s2n_connection_set_all_protocol_versions(client_conn, S2N_TLS13));
EXPECT_SUCCESS(s2n_set_connection_hello_retry_flags(client_conn));
client_conn->kex_params.server_ecc_evp_params.negotiated_curve = ecc_preferences->ecc_curves[0];
/* During HRR, A key_share list with a single key_share entry,
* corresponding to the server negotiated curve is sent by the client */
EXPECT_SUCCESS(s2n_client_key_share_extension.send(client_conn, &key_share_extension));
/* should contain keyshare for only server negotiated curve */
struct s2n_ecc_evp_params *client_ecc_evp_params = &client_conn->kex_params.client_ecc_evp_params;
EXPECT_EQUAL(client_ecc_evp_params->negotiated_curve, client_conn->kex_params.server_ecc_evp_params.negotiated_curve);
EXPECT_NOT_NULL(client_ecc_evp_params->negotiated_curve);
EXPECT_NOT_NULL(client_ecc_evp_params->evp_pkey);
server_conn->kex_params.server_ecc_evp_params.negotiated_curve = ecc_preferences->ecc_curves[0];
EXPECT_SUCCESS(s2n_connection_set_all_protocol_versions(server_conn, S2N_TLS13));
EXPECT_SUCCESS(s2n_client_key_share_extension.recv(server_conn, &key_share_extension));
/* should read all data */
EXPECT_EQUAL(s2n_stuffer_data_available(&key_share_extension), 0);
/* Verify that a keyshare list with a single keyshare corresponding to the server negotiated curve is received */
struct s2n_ecc_evp_params *server_ecc_evp_params = &server_conn->kex_params.client_ecc_evp_params;
EXPECT_EQUAL(server_ecc_evp_params->negotiated_curve, server_conn->kex_params.server_ecc_evp_params.negotiated_curve);
EXPECT_NOT_NULL(server_ecc_evp_params->negotiated_curve);
EXPECT_NOT_NULL(server_ecc_evp_params->evp_pkey);
EXPECT_SUCCESS(s2n_stuffer_free(&key_share_extension));
EXPECT_SUCCESS(s2n_connection_free(client_conn));
EXPECT_SUCCESS(s2n_connection_free(server_conn));
};
/* For HelloRetryRequests, test that s2n_client_key_share_extension.send fails,
* if the server negotiated_curve is not set and is NULL. */
{
struct s2n_connection *conn;
struct s2n_stuffer key_share_extension = { 0 };
EXPECT_NOT_NULL(conn = s2n_connection_new(S2N_CLIENT));
EXPECT_SUCCESS(s2n_stuffer_growable_alloc(&key_share_extension, 0));
/* Setup the client to have received a HelloRetryRequest */
EXPECT_MEMCPY_SUCCESS(conn->handshake_params.server_random, hello_retry_req_random, S2N_TLS_RANDOM_DATA_LEN);
EXPECT_SUCCESS(s2n_connection_set_all_protocol_versions(conn, S2N_TLS13));
EXPECT_SUCCESS(s2n_set_connection_hello_retry_flags(conn));
conn->kex_params.server_ecc_evp_params.negotiated_curve = NULL;
conn->kex_params.server_kem_group_params.kem_group = NULL;
EXPECT_FAILURE_WITH_ERRNO(s2n_client_key_share_extension.send(conn, &key_share_extension),
S2N_ERR_BAD_KEY_SHARE);
const struct s2n_ecc_preferences *ecc_preferences = NULL;
EXPECT_SUCCESS(s2n_connection_get_ecc_preferences(conn, &ecc_preferences));
EXPECT_NOT_NULL(ecc_preferences);
struct s2n_ecc_evp_params *ecc_evp_params = &conn->kex_params.client_ecc_evp_params;
EXPECT_NULL(ecc_evp_params->negotiated_curve);
EXPECT_NULL(ecc_evp_params->evp_pkey);
EXPECT_SUCCESS(s2n_stuffer_free(&key_share_extension));
EXPECT_SUCCESS(s2n_connection_free(conn));
};
/* For HelloRetryRequests, verify that we cannot resend an existing share. */
{
struct s2n_connection *conn = s2n_connection_new(S2N_CLIENT);
EXPECT_NOT_NULL(conn);
const struct s2n_ecc_preferences *ecc_preferences = NULL;
EXPECT_SUCCESS(s2n_connection_get_ecc_preferences(conn, &ecc_preferences));
EXPECT_NOT_NULL(ecc_preferences);
const struct s2n_ecc_named_curve *curve = ecc_preferences->ecc_curves[0];
struct s2n_stuffer first_extension = { 0 }, second_extension = { 0 };
EXPECT_SUCCESS(s2n_stuffer_growable_alloc(&first_extension, 0));
EXPECT_SUCCESS(s2n_stuffer_growable_alloc(&second_extension, 0));
EXPECT_SUCCESS(s2n_client_key_share_extension.send(conn, &first_extension));
EXPECT_EQUAL(conn->kex_params.client_ecc_evp_params.negotiated_curve, curve);
EXPECT_NOT_NULL(conn->kex_params.client_ecc_evp_params.evp_pkey);
/* Setup the client to have received a HelloRetryRequest */
EXPECT_MEMCPY_SUCCESS(conn->handshake_params.server_random, hello_retry_req_random, S2N_TLS_RANDOM_DATA_LEN);
EXPECT_SUCCESS(s2n_connection_set_all_protocol_versions(conn, S2N_TLS13));
EXPECT_SUCCESS(s2n_set_connection_hello_retry_flags(conn));
conn->early_data_state = S2N_EARLY_DATA_REJECTED;
conn->kex_params.server_ecc_evp_params.negotiated_curve = curve;
EXPECT_FAILURE_WITH_ERRNO(s2n_client_key_share_extension.send(conn, &second_extension),
S2N_ERR_BAD_KEY_SHARE);
EXPECT_SUCCESS(s2n_stuffer_free(&first_extension));
EXPECT_SUCCESS(s2n_stuffer_free(&second_extension));
EXPECT_SUCCESS(s2n_connection_free(conn));
};
};
/* Test s2n_client_key_share_extension.recv */
{
/* Test that s2n_client_key_share_extension.recv is a no-op
* if not using TLS1.3 */
{
struct s2n_connection *client_conn, *server_conn;
EXPECT_NOT_NULL(client_conn = s2n_connection_new(S2N_CLIENT));
EXPECT_NOT_NULL(server_conn = s2n_connection_new(S2N_SERVER));
EXPECT_OK(s2n_set_all_mutually_supported_groups(server_conn));
DEFER_CLEANUP(struct s2n_stuffer key_share_extension, s2n_stuffer_free);
EXPECT_SUCCESS(s2n_stuffer_growable_alloc(&key_share_extension, 0));
EXPECT_SUCCESS(s2n_client_key_share_extension.send(client_conn, &key_share_extension));
uint16_t key_share_extension_size = s2n_stuffer_data_available(&key_share_extension);
EXPECT_SUCCESS(s2n_enable_tls13_in_test());
server_conn->actual_protocol_version = S2N_TLS12;
EXPECT_SUCCESS(s2n_extension_recv(&s2n_client_key_share_extension, server_conn, &key_share_extension));
EXPECT_EQUAL(s2n_stuffer_data_available(&key_share_extension), key_share_extension_size);
EXPECT_SUCCESS(s2n_enable_tls13_in_test());
server_conn->actual_protocol_version = S2N_TLS13;
EXPECT_SUCCESS(s2n_client_key_share_extension.recv(server_conn, &key_share_extension));
EXPECT_EQUAL(s2n_stuffer_data_available(&key_share_extension), 0);
EXPECT_SUCCESS(s2n_connection_free(client_conn));
EXPECT_SUCCESS(s2n_connection_free(server_conn));
};
/* Test that s2n_client_key_share_extension.recv can read and parse
* the result of s2n_client_key_share_extension.send */
{
struct s2n_connection *client_conn, *server_conn;
struct s2n_stuffer key_share_extension = { 0 };
EXPECT_NOT_NULL(client_conn = s2n_connection_new(S2N_CLIENT));
EXPECT_NOT_NULL(server_conn = s2n_connection_new(S2N_SERVER));
server_conn->actual_protocol_version = S2N_TLS13;
EXPECT_SUCCESS(s2n_stuffer_growable_alloc(&key_share_extension, 0));
EXPECT_OK(s2n_set_all_mutually_supported_groups(server_conn));
EXPECT_SUCCESS(s2n_client_key_share_extension.send(client_conn, &key_share_extension));
EXPECT_SUCCESS(s2n_client_key_share_extension.recv(server_conn, &key_share_extension));
const struct s2n_ecc_preferences *ecc_pref = NULL;
EXPECT_SUCCESS(s2n_connection_get_ecc_preferences(server_conn, &ecc_pref));
EXPECT_NOT_NULL(ecc_pref);
/* should read all data */
EXPECT_EQUAL(s2n_stuffer_data_available(&key_share_extension), 0);
/* should set internal state the same as the client */
struct s2n_ecc_evp_params *server_ecc_evp_params = &server_conn->kex_params.client_ecc_evp_params;
struct s2n_ecc_evp_params *client_ecc_evp_params = &client_conn->kex_params.client_ecc_evp_params;
EXPECT_NOT_NULL(server_ecc_evp_params->negotiated_curve);
EXPECT_NOT_NULL(server_ecc_evp_params->evp_pkey);
EXPECT_TRUE(s2n_public_ecc_keys_are_equal(server_ecc_evp_params, client_ecc_evp_params));
EXPECT_SUCCESS(s2n_stuffer_free(&key_share_extension));
EXPECT_SUCCESS(s2n_connection_free(client_conn));
EXPECT_SUCCESS(s2n_connection_free(server_conn));
};
/* Test that s2n_client_key_share_extension.recv can handle an empty keyshare list */
{
/* Just the uint16_t length as "0" */
uint8_t empty_keyshare_extension[] = { 0x00, 0x00 };
struct s2n_connection *server_conn = s2n_connection_new(S2N_SERVER);
EXPECT_NOT_NULL(server_conn);
server_conn->actual_protocol_version = S2N_TLS13;
EXPECT_OK(s2n_set_all_mutually_supported_groups(server_conn));
struct s2n_stuffer key_share_extension = { 0 };
EXPECT_SUCCESS(s2n_stuffer_alloc(&key_share_extension, sizeof(empty_keyshare_extension)));
EXPECT_SUCCESS(s2n_stuffer_write_bytes(&key_share_extension, empty_keyshare_extension, sizeof(empty_keyshare_extension)));
EXPECT_SUCCESS(s2n_client_key_share_extension.recv(server_conn, &key_share_extension));
EXPECT_EQUAL(s2n_stuffer_data_available(&key_share_extension), 0);
/* Triggers retry */
EXPECT_TRUE(IS_HELLO_RETRY_HANDSHAKE(server_conn));
EXPECT_SUCCESS(s2n_stuffer_free(&key_share_extension));
EXPECT_SUCCESS(s2n_connection_free(server_conn));
};
/* Test that s2n_client_key_share_extension.recv can handle a keyshare for
* a supported curve that isn't its first choice curve. */
{
struct s2n_connection *server_conn = s2n_connection_new(S2N_SERVER);
EXPECT_NOT_NULL(server_conn);
server_conn->actual_protocol_version = S2N_TLS13;
EXPECT_OK(s2n_set_all_mutually_supported_groups(server_conn));
const struct s2n_ecc_preferences *ecc_pref = NULL;
EXPECT_SUCCESS(s2n_connection_get_ecc_preferences(server_conn, &ecc_pref));
EXPECT_NOT_NULL(ecc_pref);
EXPECT_TRUE(ecc_pref->count >= 2);
struct s2n_ecc_evp_params client_ecc_evp_params = { .negotiated_curve = ecc_pref->ecc_curves[1] };
struct s2n_stuffer key_share_extension = { 0 };
EXPECT_SUCCESS(s2n_stuffer_growable_alloc(&key_share_extension, 0));
struct s2n_stuffer_reservation keyshare_list_size = { 0 };
EXPECT_SUCCESS(s2n_stuffer_reserve_uint16(&key_share_extension, &keyshare_list_size));
EXPECT_SUCCESS(s2n_ecdhe_parameters_send(&client_ecc_evp_params, &key_share_extension));
EXPECT_SUCCESS(s2n_stuffer_write_vector_size(&keyshare_list_size));
EXPECT_SUCCESS(s2n_client_key_share_extension.recv(server_conn, &key_share_extension));
EXPECT_EQUAL(s2n_stuffer_data_available(&key_share_extension), 0);
/* Does not trigger retries */
EXPECT_FALSE(IS_HELLO_RETRY_HANDSHAKE(server_conn));
/* Expected share present */
struct s2n_ecc_evp_params *server_ecc_evp_params = &server_conn->kex_params.client_ecc_evp_params;
EXPECT_NOT_NULL(server_ecc_evp_params->negotiated_curve);
EXPECT_NOT_NULL(server_ecc_evp_params->evp_pkey);
EXPECT_TRUE(s2n_public_ecc_keys_are_equal(server_ecc_evp_params, &client_ecc_evp_params));
EXPECT_SUCCESS(s2n_ecc_evp_params_free(&client_ecc_evp_params));
EXPECT_SUCCESS(s2n_stuffer_free(&key_share_extension));
EXPECT_SUCCESS(s2n_connection_free(server_conn));
};
/* Test that s2n_client_key_share_extension.recv can handle multiple keyshares */
{
struct s2n_connection *server_conn = s2n_connection_new(S2N_SERVER);
EXPECT_NOT_NULL(server_conn);
server_conn->actual_protocol_version = S2N_TLS13;
EXPECT_OK(s2n_set_all_mutually_supported_groups(server_conn));
const struct s2n_ecc_preferences *ecc_pref = NULL;
EXPECT_SUCCESS(s2n_connection_get_ecc_preferences(server_conn, &ecc_pref));
EXPECT_NOT_NULL(ecc_pref);
EXPECT_TRUE(ecc_pref->count >= 2);
struct s2n_ecc_evp_params client_ecc_evp_params[] = {
{ .negotiated_curve = ecc_pref->ecc_curves[0] },
{ .negotiated_curve = ecc_pref->ecc_curves[1] }
};
struct s2n_stuffer key_share_extension = { 0 };
EXPECT_SUCCESS(s2n_stuffer_growable_alloc(&key_share_extension, 0));
struct s2n_stuffer_reservation keyshare_list_size = { 0 };
EXPECT_SUCCESS(s2n_stuffer_reserve_uint16(&key_share_extension, &keyshare_list_size));
EXPECT_SUCCESS(s2n_ecdhe_parameters_send(&client_ecc_evp_params[0], &key_share_extension));
EXPECT_SUCCESS(s2n_ecdhe_parameters_send(&client_ecc_evp_params[1], &key_share_extension));
EXPECT_SUCCESS(s2n_stuffer_write_vector_size(&keyshare_list_size));
EXPECT_SUCCESS(s2n_client_key_share_extension.recv(server_conn, &key_share_extension));
EXPECT_EQUAL(s2n_stuffer_data_available(&key_share_extension), 0);
/* Does not trigger retries */
EXPECT_FALSE(IS_HELLO_RETRY_HANDSHAKE(server_conn));
/* Highest priority share (0) present */
struct s2n_ecc_evp_params *server_ecc_evp_params = &server_conn->kex_params.client_ecc_evp_params;
EXPECT_NOT_NULL(server_ecc_evp_params->negotiated_curve);
EXPECT_NOT_NULL(server_ecc_evp_params->evp_pkey);
EXPECT_TRUE(s2n_public_ecc_keys_are_equal(server_ecc_evp_params, &client_ecc_evp_params[0]));
for (size_t i = 0; i < s2n_array_len(client_ecc_evp_params); i++) {
EXPECT_SUCCESS(s2n_ecc_evp_params_free(&client_ecc_evp_params[i]));
}
EXPECT_SUCCESS(s2n_stuffer_free(&key_share_extension));
EXPECT_SUCCESS(s2n_connection_free(server_conn));
};
/* Test that s2n_client_key_share_extension.recv selects the highest priority share,
* even if it appears last in the client's list of shares. */
{
struct s2n_connection *server_conn = s2n_connection_new(S2N_SERVER);
EXPECT_NOT_NULL(server_conn);
server_conn->actual_protocol_version = S2N_TLS13;
EXPECT_OK(s2n_set_all_mutually_supported_groups(server_conn));
const struct s2n_ecc_preferences *ecc_pref = NULL;
EXPECT_SUCCESS(s2n_connection_get_ecc_preferences(server_conn, &ecc_pref));
EXPECT_NOT_NULL(ecc_pref);
EXPECT_TRUE(ecc_pref->count >= 2);
struct s2n_ecc_evp_params client_ecc_evp_params[] = {
{ .negotiated_curve = ecc_pref->ecc_curves[0] },
{ .negotiated_curve = ecc_pref->ecc_curves[1] }
};
struct s2n_stuffer key_share_extension = { 0 };
EXPECT_SUCCESS(s2n_stuffer_growable_alloc(&key_share_extension, 0));
struct s2n_stuffer_reservation keyshare_list_size = { 0 };
EXPECT_SUCCESS(s2n_stuffer_reserve_uint16(&key_share_extension, &keyshare_list_size));
EXPECT_SUCCESS(s2n_ecdhe_parameters_send(&client_ecc_evp_params[1], &key_share_extension));
EXPECT_SUCCESS(s2n_ecdhe_parameters_send(&client_ecc_evp_params[1], &key_share_extension));
EXPECT_SUCCESS(s2n_ecdhe_parameters_send(&client_ecc_evp_params[0], &key_share_extension));
EXPECT_SUCCESS(s2n_stuffer_write_vector_size(&keyshare_list_size));
EXPECT_SUCCESS(s2n_client_key_share_extension.recv(server_conn, &key_share_extension));
EXPECT_EQUAL(s2n_stuffer_data_available(&key_share_extension), 0);
/* Does not trigger retries */
EXPECT_FALSE(IS_HELLO_RETRY_HANDSHAKE(server_conn));
/* Highest priority curve (0) share present */
struct s2n_ecc_evp_params *server_ecc_evp_params = &server_conn->kex_params.client_ecc_evp_params;
EXPECT_EQUAL(server_ecc_evp_params->negotiated_curve, ecc_pref->ecc_curves[0]);
EXPECT_NOT_NULL(server_ecc_evp_params->evp_pkey);
EXPECT_TRUE(s2n_public_ecc_keys_are_equal(server_ecc_evp_params, &client_ecc_evp_params[0]));
for (size_t i = 0; i < s2n_array_len(client_ecc_evp_params); i++) {
EXPECT_SUCCESS(s2n_ecc_evp_params_free(&client_ecc_evp_params[i]));
}
EXPECT_SUCCESS(s2n_stuffer_free(&key_share_extension));
EXPECT_SUCCESS(s2n_connection_free(server_conn));
};
/* Test that s2n_client_key_share_extension.recv ignores shares for curves not offered
* by the client / "mutually supported", and triggers a retry instead.
*/
{
struct s2n_connection *server_conn = s2n_connection_new(S2N_SERVER);
EXPECT_NOT_NULL(server_conn);
server_conn->actual_protocol_version = S2N_TLS13;
/* Do NOT mark curve 0 as mutually supported */
EXPECT_OK(s2n_set_all_mutually_supported_groups(server_conn));
server_conn->kex_params.mutually_supported_curves[0] = NULL;
const struct s2n_ecc_preferences *ecc_pref = NULL;
EXPECT_SUCCESS(s2n_connection_get_ecc_preferences(server_conn, &ecc_pref));
EXPECT_NOT_NULL(ecc_pref);
EXPECT_TRUE(ecc_pref->count >= 2);
struct s2n_ecc_evp_params client_ecc_evp_params = { .negotiated_curve = ecc_pref->ecc_curves[0] };
struct s2n_stuffer key_share_extension = { 0 };
EXPECT_SUCCESS(s2n_stuffer_growable_alloc(&key_share_extension, 0));
struct s2n_stuffer_reservation keyshare_list_size = { 0 };
EXPECT_SUCCESS(s2n_stuffer_reserve_uint16(&key_share_extension, &keyshare_list_size));
EXPECT_SUCCESS(s2n_ecdhe_parameters_send(&client_ecc_evp_params, &key_share_extension));
EXPECT_SUCCESS(s2n_stuffer_write_vector_size(&keyshare_list_size));
EXPECT_SUCCESS(s2n_client_key_share_extension.recv(server_conn, &key_share_extension));
EXPECT_EQUAL(s2n_stuffer_data_available(&key_share_extension), 0);
/* Client key share ignored, so retry triggered */
EXPECT_TRUE(IS_HELLO_RETRY_HANDSHAKE(server_conn));
/* No valid client key share present */
struct s2n_ecc_evp_params *server_ecc_evp_params = &server_conn->kex_params.client_ecc_evp_params;
EXPECT_NULL(server_ecc_evp_params->negotiated_curve);
EXPECT_NULL(server_ecc_evp_params->evp_pkey);
EXPECT_SUCCESS(s2n_ecc_evp_params_free(&client_ecc_evp_params));
EXPECT_SUCCESS(s2n_stuffer_free(&key_share_extension));
EXPECT_SUCCESS(s2n_connection_free(server_conn));
};
/* Test that s2n_client_key_share_extension.recv ignores shares for curves not offered
* by the client / "mutually supported", and chooses a lower priority curve instead.
*/
{
struct s2n_connection *server_conn = s2n_connection_new(S2N_SERVER);
EXPECT_NOT_NULL(server_conn);
server_conn->actual_protocol_version = S2N_TLS13;
/* Do NOT mark curve 0 as mutually supported */
EXPECT_OK(s2n_set_all_mutually_supported_groups(server_conn));
server_conn->kex_params.mutually_supported_curves[0] = NULL;
const struct s2n_ecc_preferences *ecc_pref = NULL;
EXPECT_SUCCESS(s2n_connection_get_ecc_preferences(server_conn, &ecc_pref));
EXPECT_NOT_NULL(ecc_pref);
EXPECT_TRUE(ecc_pref->count >= 2);
struct s2n_ecc_evp_params client_ecc_evp_params[] = {
{ .negotiated_curve = ecc_pref->ecc_curves[0] },
{ .negotiated_curve = ecc_pref->ecc_curves[1] }
};
struct s2n_stuffer key_share_extension = { 0 };
EXPECT_SUCCESS(s2n_stuffer_growable_alloc(&key_share_extension, 0));
struct s2n_stuffer_reservation keyshare_list_size = { 0 };
EXPECT_SUCCESS(s2n_stuffer_reserve_uint16(&key_share_extension, &keyshare_list_size));
EXPECT_SUCCESS(s2n_ecdhe_parameters_send(&client_ecc_evp_params[0], &key_share_extension));
EXPECT_SUCCESS(s2n_ecdhe_parameters_send(&client_ecc_evp_params[1], &key_share_extension));
EXPECT_SUCCESS(s2n_stuffer_write_vector_size(&keyshare_list_size));
EXPECT_SUCCESS(s2n_client_key_share_extension.recv(server_conn, &key_share_extension));
EXPECT_EQUAL(s2n_stuffer_data_available(&key_share_extension), 0);
/* Does not trigger a retry */
EXPECT_FALSE(IS_HELLO_RETRY_HANDSHAKE(server_conn));
/* Second highest priority curve (1) share present, because highest priority not "mutually supported" */
struct s2n_ecc_evp_params *server_ecc_evp_params = &server_conn->kex_params.client_ecc_evp_params;
EXPECT_EQUAL(server_ecc_evp_params->negotiated_curve, ecc_pref->ecc_curves[1]);
EXPECT_NOT_NULL(server_ecc_evp_params->evp_pkey);
EXPECT_TRUE(s2n_public_ecc_keys_are_equal(server_ecc_evp_params, &client_ecc_evp_params[1]));
for (size_t i = 0; i < s2n_array_len(client_ecc_evp_params); i++) {
EXPECT_SUCCESS(s2n_ecc_evp_params_free(&client_ecc_evp_params[i]));
}
EXPECT_SUCCESS(s2n_stuffer_free(&key_share_extension));
EXPECT_SUCCESS(s2n_connection_free(server_conn));
};
/* Test that s2n_client_key_share_extension.recv errors on client shares size larger
* than available data */
{
struct s2n_connection *conn;
struct s2n_stuffer key_share_extension = { 0 };
EXPECT_NOT_NULL(conn = s2n_connection_new(S2N_SERVER));
conn->actual_protocol_version = S2N_TLS13;
EXPECT_OK(s2n_set_all_mutually_supported_groups(conn));
EXPECT_SUCCESS(s2n_stuffer_growable_alloc(&key_share_extension, 0));
const struct s2n_ecc_preferences *ecc_pref = NULL;
EXPECT_SUCCESS(s2n_connection_get_ecc_preferences(conn, &ecc_pref));
EXPECT_NOT_NULL(ecc_pref);
EXPECT_SUCCESS(s2n_stuffer_write_uint16(&key_share_extension, ecc_pref->ecc_curves[0]->share_size * 10));
EXPECT_SUCCESS(s2n_write_named_curve(&key_share_extension, ecc_pref->ecc_curves[0]));
EXPECT_FAILURE(s2n_client_key_share_extension.recv(conn, &key_share_extension));
EXPECT_SUCCESS(s2n_stuffer_free(&key_share_extension));
EXPECT_SUCCESS(s2n_connection_free(conn));
};
/* Test that s2n_client_key_share_extension.recv errors on key share size longer than data */
{
struct s2n_connection *conn;
struct s2n_stuffer key_share_extension = { 0 };
EXPECT_NOT_NULL(conn = s2n_connection_new(S2N_SERVER));
conn->actual_protocol_version = S2N_TLS13;
EXPECT_OK(s2n_set_all_mutually_supported_groups(conn));
EXPECT_SUCCESS(s2n_stuffer_growable_alloc(&key_share_extension, 0));
const struct s2n_ecc_preferences *ecc_pref = NULL;
EXPECT_SUCCESS(s2n_connection_get_ecc_preferences(conn, &ecc_pref));
EXPECT_NOT_NULL(ecc_pref);
/* Write curve with huge length */
S2N_PREPARE_DATA_LENGTH(&key_share_extension);
EXPECT_SUCCESS(s2n_write_key_share(&key_share_extension,
ecc_pref->ecc_curves[0]->iana_id, ecc_pref->ecc_curves[0]->share_size * 10, ecc_pref->ecc_curves[0]));
S2N_WRITE_DATA_LENGTH(&key_share_extension);
EXPECT_FAILURE(s2n_client_key_share_extension.recv(conn, &key_share_extension));
EXPECT_SUCCESS(s2n_stuffer_free(&key_share_extension));
EXPECT_SUCCESS(s2n_connection_free(conn));
};
/* Test that s2n_client_key_share_extension.recv accepts a subset of supported curves */
{
struct s2n_connection *conn;
struct s2n_stuffer key_share_extension = { 0 };
EXPECT_NOT_NULL(conn = s2n_connection_new(S2N_SERVER));
conn->actual_protocol_version = S2N_TLS13;
EXPECT_OK(s2n_set_all_mutually_supported_groups(conn));
EXPECT_SUCCESS(s2n_stuffer_growable_alloc(&key_share_extension, 0));
const struct s2n_ecc_preferences *ecc_pref = NULL;
EXPECT_SUCCESS(s2n_connection_get_ecc_preferences(conn, &ecc_pref));
EXPECT_NOT_NULL(ecc_pref);
/* Write only first curve */
S2N_PREPARE_DATA_LENGTH(&key_share_extension);
EXPECT_SUCCESS(s2n_write_named_curve(&key_share_extension, ecc_pref->ecc_curves[0]));
S2N_WRITE_DATA_LENGTH(&key_share_extension);
EXPECT_SUCCESS(s2n_client_key_share_extension.recv(conn, &key_share_extension));
/* should read all data */
EXPECT_EQUAL(s2n_stuffer_data_available(&key_share_extension), 0);
/* should have initialized first curve */
struct s2n_ecc_evp_params *ecc_evp_params = &conn->kex_params.client_ecc_evp_params;
EXPECT_NOT_NULL(ecc_evp_params->negotiated_curve);
EXPECT_NOT_NULL(ecc_evp_params->evp_pkey);
EXPECT_EQUAL(ecc_evp_params->negotiated_curve, ecc_pref->ecc_curves[0]);
EXPECT_SUCCESS(s2n_stuffer_free(&key_share_extension));
EXPECT_SUCCESS(s2n_connection_free(conn));
};
/* Test that s2n_client_key_share_extension.recv handles empty client share list */
{
struct s2n_connection *server_conn;
struct s2n_stuffer key_share_extension = { 0 };
EXPECT_NOT_NULL(server_conn = s2n_connection_new(S2N_SERVER));
EXPECT_SUCCESS(s2n_connection_set_all_protocol_versions(server_conn, S2N_TLS13));
EXPECT_OK(s2n_set_all_mutually_supported_groups(server_conn));
EXPECT_SUCCESS(s2n_stuffer_growable_alloc(&key_share_extension, 0));
const struct s2n_ecc_preferences *ecc_pref = NULL;
EXPECT_SUCCESS(s2n_connection_get_ecc_preferences(server_conn, &ecc_pref));
EXPECT_NOT_NULL(ecc_pref);
EXPECT_SUCCESS(s2n_stuffer_write_uint16(&key_share_extension, 0));
EXPECT_SUCCESS(s2n_client_key_share_extension.recv(server_conn, &key_share_extension));
/* should not have initialized any curves */
struct s2n_ecc_evp_params *ecc_evp_params = &server_conn->kex_params.client_ecc_evp_params;
EXPECT_NULL(ecc_evp_params->negotiated_curve);
EXPECT_NULL(ecc_evp_params->evp_pkey);
EXPECT_SUCCESS(s2n_stuffer_free(&key_share_extension));
EXPECT_SUCCESS(s2n_connection_free(server_conn));
};
/* Test that s2n_client_key_share_extension.recv ignores unsupported curves */
{
struct s2n_connection *conn;
struct s2n_stuffer key_share_extension = { 0 };
EXPECT_NOT_NULL(conn = s2n_connection_new(S2N_SERVER));
EXPECT_SUCCESS(s2n_connection_set_all_protocol_versions(conn, S2N_TLS13));
EXPECT_OK(s2n_set_all_mutually_supported_groups(conn));
EXPECT_SUCCESS(s2n_stuffer_growable_alloc(&key_share_extension, 0));
const struct s2n_ecc_preferences *ecc_pref = NULL;
EXPECT_SUCCESS(s2n_connection_get_ecc_preferences(conn, &ecc_pref));
EXPECT_NOT_NULL(ecc_pref);
S2N_PREPARE_DATA_LENGTH(&key_share_extension);
/* Write unsupported curves */
/* 0 -> unallocated_RESERVED */
EXPECT_SUCCESS(s2n_write_key_share(&key_share_extension,
0, ecc_pref->ecc_curves[0]->share_size, ecc_pref->ecc_curves[0]));
/* 0xFF01 -> obsolete_RESERVED */
EXPECT_SUCCESS(s2n_write_key_share(&key_share_extension,
65281, ecc_pref->ecc_curves[0]->share_size, ecc_pref->ecc_curves[0]));
S2N_WRITE_DATA_LENGTH(&key_share_extension);
EXPECT_SUCCESS(s2n_client_key_share_extension.recv(conn, &key_share_extension));
/* should read all data */
EXPECT_EQUAL(s2n_stuffer_data_available(&key_share_extension), 0);
/* should not have initialized any curves */
struct s2n_ecc_evp_params *ecc_evp_params = &conn->kex_params.client_ecc_evp_params;
EXPECT_NULL(ecc_evp_params->negotiated_curve);
EXPECT_NULL(ecc_evp_params->evp_pkey);
EXPECT_SUCCESS(s2n_stuffer_free(&key_share_extension));
EXPECT_SUCCESS(s2n_connection_free(conn));
};
/* Test that s2n_client_key_share_extension.recv ignores curves with incorrect key size */
{
struct s2n_connection *conn;
struct s2n_stuffer key_share_extension = { 0 };
EXPECT_NOT_NULL(conn = s2n_connection_new(S2N_SERVER));
EXPECT_SUCCESS(s2n_connection_set_all_protocol_versions(conn, S2N_TLS13));
EXPECT_OK(s2n_set_all_mutually_supported_groups(conn));
EXPECT_SUCCESS(s2n_stuffer_growable_alloc(&key_share_extension, 0));
const struct s2n_ecc_preferences *ecc_pref = NULL;
EXPECT_SUCCESS(s2n_connection_get_ecc_preferences(conn, &ecc_pref));
EXPECT_NOT_NULL(ecc_pref);
/* Write supported curve, but with a different curve's size */
S2N_PREPARE_DATA_LENGTH(&key_share_extension);
EXPECT_SUCCESS(s2n_write_key_share(&key_share_extension,
ecc_pref->ecc_curves[0]->iana_id, ecc_pref->ecc_curves[1]->share_size, ecc_pref->ecc_curves[1]));
S2N_WRITE_DATA_LENGTH(&key_share_extension);
EXPECT_SUCCESS(s2n_client_key_share_extension.recv(conn, &key_share_extension));
/* should read all data */
EXPECT_EQUAL(s2n_stuffer_data_available(&key_share_extension), 0);
/* should not have initialized any curves */
struct s2n_ecc_evp_params *ecc_evp_params = &conn->kex_params.client_ecc_evp_params;
EXPECT_NULL(ecc_evp_params->negotiated_curve);
EXPECT_NULL(ecc_evp_params->evp_pkey);
EXPECT_SUCCESS(s2n_stuffer_free(&key_share_extension));
EXPECT_SUCCESS(s2n_connection_free(conn));
};
/* Test that s2n_client_key_share_extension.recv uses first instance of duplicate curves */
{
struct s2n_connection *server_conn;
struct s2n_stuffer key_share_extension = { 0 };
struct s2n_ecc_evp_params first_params, second_params;
int supported_curve_index = 0;
EXPECT_NOT_NULL(server_conn = s2n_connection_new(S2N_SERVER));
EXPECT_SUCCESS(s2n_connection_set_all_protocol_versions(server_conn, S2N_TLS13));
EXPECT_OK(s2n_set_all_mutually_supported_groups(server_conn));
EXPECT_SUCCESS(s2n_stuffer_growable_alloc(&key_share_extension, 0));
const struct s2n_ecc_preferences *ecc_pref = NULL;
EXPECT_SUCCESS(s2n_connection_get_ecc_preferences(server_conn, &ecc_pref));
EXPECT_NOT_NULL(ecc_pref);
S2N_PREPARE_DATA_LENGTH(&key_share_extension);
/* Write first curve once */
first_params.negotiated_curve = ecc_pref->ecc_curves[supported_curve_index];
first_params.evp_pkey = NULL;
EXPECT_SUCCESS(s2n_ecdhe_parameters_send(&first_params, &key_share_extension));
/* Write first curve again */
second_params.negotiated_curve = ecc_pref->ecc_curves[supported_curve_index];
second_params.evp_pkey = NULL;
EXPECT_SUCCESS(s2n_ecdhe_parameters_send(&second_params, &key_share_extension));
S2N_WRITE_DATA_LENGTH(&key_share_extension);
EXPECT_SUCCESS(s2n_client_key_share_extension.recv(server_conn, &key_share_extension));
/* should read all data */
EXPECT_EQUAL(s2n_stuffer_data_available(&key_share_extension), 0);
/* should have only copied the first set of params */
EXPECT_TRUE(s2n_public_ecc_keys_are_equal(
&server_conn->kex_params.client_ecc_evp_params, &first_params));
EXPECT_SUCCESS(s2n_stuffer_free(&key_share_extension));
EXPECT_SUCCESS(s2n_connection_free(server_conn));
EXPECT_SUCCESS(s2n_ecc_evp_params_free(&first_params));
EXPECT_SUCCESS(s2n_ecc_evp_params_free(&second_params));
};
/* Test that s2n_client_key_share_extension.recv ignores ECDHE points that can't be parsed */
{
struct s2n_connection *conn;
struct s2n_stuffer key_share_extension = { 0 };
struct s2n_config *config;
EXPECT_NOT_NULL(config = s2n_config_new());
/* Explicitly set the ecc_preferences list to only contain the curves p-256 and p-384 */
EXPECT_SUCCESS(s2n_config_set_cipher_preferences(config, "20140601"));
EXPECT_NOT_NULL(conn = s2n_connection_new(S2N_SERVER));
EXPECT_SUCCESS(s2n_connection_set_all_protocol_versions(conn, S2N_TLS13));
EXPECT_OK(s2n_set_all_mutually_supported_groups(conn));
EXPECT_SUCCESS(s2n_stuffer_growable_alloc(&key_share_extension, 0));
EXPECT_SUCCESS(s2n_connection_set_config(conn, config));
const struct s2n_ecc_preferences *ecc_pref = NULL;
EXPECT_SUCCESS(s2n_connection_get_ecc_preferences(conn, &ecc_pref));
EXPECT_NOT_NULL(ecc_pref);
/* Write first curve */
S2N_PREPARE_DATA_LENGTH(&key_share_extension);
EXPECT_SUCCESS(s2n_write_named_curve(&key_share_extension, ecc_pref->ecc_curves[0]));
S2N_WRITE_DATA_LENGTH(&key_share_extension);
/* Mess up point by erasing most of it */
int data_size = s2n_stuffer_data_available(&key_share_extension);
EXPECT_SUCCESS(s2n_stuffer_wipe_n(&key_share_extension, data_size / 2));
EXPECT_SUCCESS(s2n_stuffer_skip_write(&key_share_extension, data_size / 2));
EXPECT_SUCCESS(s2n_client_key_share_extension.recv(conn, &key_share_extension));
/* should read all data */
EXPECT_EQUAL(s2n_stuffer_data_available(&key_share_extension), 0);
/* should not have initialized any curves */
struct s2n_ecc_evp_params *ecc_evp_params = &conn->kex_params.client_ecc_evp_params;
EXPECT_NULL(ecc_evp_params->negotiated_curve);
EXPECT_NULL(ecc_evp_params->evp_pkey);
EXPECT_SUCCESS(s2n_stuffer_free(&key_share_extension));
EXPECT_SUCCESS(s2n_connection_free(conn));
EXPECT_SUCCESS(s2n_config_free(config));
};
/* Test that s2n_client_key_share_extension.recv ignores ECDHE points that can't be parsed,
* and continues to parse valid key shares afterwards. */
{
struct s2n_config *config;
EXPECT_NOT_NULL(config = s2n_config_new());
/* Explicitly set the ecc_preferences list to only contain the curves p-256 and p-384 */
EXPECT_SUCCESS(s2n_config_set_cipher_preferences(config, "20140601"));
struct s2n_connection *server_conn = s2n_connection_new(S2N_SERVER);
EXPECT_NOT_NULL(server_conn);
EXPECT_SUCCESS(s2n_connection_set_all_protocol_versions(server_conn, S2N_TLS13));
EXPECT_OK(s2n_set_all_mutually_supported_groups(server_conn));
EXPECT_SUCCESS(s2n_connection_set_config(server_conn, config));
struct s2n_stuffer key_share_extension = { 0 };
EXPECT_SUCCESS(s2n_stuffer_growable_alloc(&key_share_extension, 0));
const struct s2n_ecc_preferences *ecc_pref = NULL;
EXPECT_SUCCESS(s2n_connection_get_ecc_preferences(server_conn, &ecc_pref));
EXPECT_NOT_NULL(ecc_pref);
EXPECT_TRUE(ecc_pref->count >= 2);
struct s2n_ecc_evp_params client_ecc_evp_params[] = {
{ .negotiated_curve = ecc_pref->ecc_curves[0] },
{ .negotiated_curve = ecc_pref->ecc_curves[1] }
};
/* Write share list length */
struct s2n_stuffer_reservation keyshare_list_size = { 0 };
EXPECT_SUCCESS(s2n_stuffer_reserve_uint16(&key_share_extension, &keyshare_list_size));
/* Write first share. Mess up point by erasing most of it */
EXPECT_SUCCESS(s2n_ecdhe_parameters_send(&client_ecc_evp_params[0], &key_share_extension));
int data_size = s2n_stuffer_data_available(&key_share_extension);
EXPECT_SUCCESS(s2n_stuffer_wipe_n(&key_share_extension, data_size / 2));
EXPECT_SUCCESS(s2n_stuffer_skip_write(&key_share_extension, data_size / 2));
/* Write second, valid share */
EXPECT_SUCCESS(s2n_ecdhe_parameters_send(&client_ecc_evp_params[1], &key_share_extension));
/* Finish share list length */
EXPECT_SUCCESS(s2n_stuffer_write_vector_size(&keyshare_list_size));
EXPECT_SUCCESS(s2n_client_key_share_extension.recv(server_conn, &key_share_extension));
EXPECT_EQUAL(s2n_stuffer_data_available(&key_share_extension), 0);
/* Should have chosen curve 1, because curve 0 was malformed */
struct s2n_ecc_evp_params *server_ecc_evp_params = &server_conn->kex_params.client_ecc_evp_params;
EXPECT_EQUAL(server_ecc_evp_params->negotiated_curve, ecc_pref->ecc_curves[1]);
EXPECT_NOT_NULL(server_ecc_evp_params->evp_pkey);
EXPECT_TRUE(s2n_public_ecc_keys_are_equal(server_ecc_evp_params, &client_ecc_evp_params[1]));
for (size_t i = 0; i < s2n_array_len(client_ecc_evp_params); i++) {
EXPECT_SUCCESS(s2n_ecc_evp_params_free(&client_ecc_evp_params[i]));
}
EXPECT_SUCCESS(s2n_stuffer_free(&key_share_extension));
EXPECT_SUCCESS(s2n_connection_free(server_conn));
EXPECT_SUCCESS(s2n_config_free(config));
};
/* Test that s2n_client_key_share_extension.recv ignores ECDHE points that can't be parsed,
* and doesn't ignore / forget / overwrite valid key shares already parsed. */
{
struct s2n_connection *server_conn = s2n_connection_new(S2N_SERVER);
EXPECT_NOT_NULL(server_conn);
EXPECT_SUCCESS(s2n_connection_set_all_protocol_versions(server_conn, S2N_TLS13));
EXPECT_OK(s2n_set_all_mutually_supported_groups(server_conn));
struct s2n_stuffer key_share_extension = { 0 };
EXPECT_SUCCESS(s2n_stuffer_growable_alloc(&key_share_extension, 0));
const struct s2n_ecc_preferences *ecc_pref = NULL;
EXPECT_SUCCESS(s2n_connection_get_ecc_preferences(server_conn, &ecc_pref));
EXPECT_NOT_NULL(ecc_pref);
EXPECT_TRUE(ecc_pref->count >= 2);
struct s2n_ecc_evp_params client_ecc_evp_params[] = {
{ .negotiated_curve = ecc_pref->ecc_curves[0] },
{ .negotiated_curve = ecc_pref->ecc_curves[1] }
};
/* Write share list length */
struct s2n_stuffer_reservation keyshare_list_size = { 0 };
EXPECT_SUCCESS(s2n_stuffer_reserve_uint16(&key_share_extension, &keyshare_list_size));
/* Write first, valid share */
EXPECT_SUCCESS(s2n_ecdhe_parameters_send(&client_ecc_evp_params[0], &key_share_extension));
/* Write second share. Mess up point by erasing most of it */
EXPECT_SUCCESS(s2n_ecdhe_parameters_send(&client_ecc_evp_params[1], &key_share_extension));
EXPECT_SUCCESS(s2n_stuffer_wipe_n(&key_share_extension, ecc_pref->ecc_curves[1]->share_size / 2));
EXPECT_SUCCESS(s2n_stuffer_skip_write(&key_share_extension, ecc_pref->ecc_curves[1]->share_size / 2));
/* Finish share list length */
EXPECT_SUCCESS(s2n_stuffer_write_vector_size(&keyshare_list_size));
EXPECT_SUCCESS(s2n_client_key_share_extension.recv(server_conn, &key_share_extension));
EXPECT_EQUAL(s2n_stuffer_data_available(&key_share_extension), 0);
/* Should have chosen highest priority key share (0) */
struct s2n_ecc_evp_params *server_ecc_evp_params = &server_conn->kex_params.client_ecc_evp_params;
EXPECT_EQUAL(server_ecc_evp_params->negotiated_curve, ecc_pref->ecc_curves[0]);
EXPECT_NOT_NULL(server_ecc_evp_params->evp_pkey);
EXPECT_TRUE(s2n_public_ecc_keys_are_equal(server_ecc_evp_params, &client_ecc_evp_params[0]));
for (size_t i = 0; i < s2n_array_len(client_ecc_evp_params); i++) {
EXPECT_SUCCESS(s2n_ecc_evp_params_free(&client_ecc_evp_params[i]));
}
EXPECT_SUCCESS(s2n_stuffer_free(&key_share_extension));
EXPECT_SUCCESS(s2n_connection_free(server_conn));
};
/* Test that s2n_client_key_share_extension.recv ignores a supported curve present in
* s2n_all_supported_curves_list but not in s2n_ecc_preferences list selected
*/
{
if (s2n_is_evp_apis_supported()) {
struct s2n_connection *conn;
struct s2n_stuffer key_share_extension = { 0 };
struct s2n_config *config;
EXPECT_NOT_NULL(config = s2n_config_new());
EXPECT_NOT_NULL(conn = s2n_connection_new(S2N_SERVER));
EXPECT_SUCCESS(s2n_connection_set_all_protocol_versions(conn, S2N_TLS13));
EXPECT_OK(s2n_set_all_mutually_supported_groups(conn));
EXPECT_SUCCESS(s2n_stuffer_growable_alloc(&key_share_extension, 0));
/* Explicitly set the ecc_preferences list to contain the curves p-256 and p-384 */
EXPECT_SUCCESS(s2n_config_set_cipher_preferences(config, "20140601"));
EXPECT_SUCCESS(s2n_connection_set_config(conn, config));
const struct s2n_ecc_preferences *ecc_pref = NULL;
EXPECT_SUCCESS(s2n_connection_get_ecc_preferences(conn, &ecc_pref));
EXPECT_NOT_NULL(ecc_pref);
/* x25519 is present in s2n_all_supported_curves_list but not in the "default" list */
const struct s2n_ecc_named_curve *test_curve = &s2n_ecc_curve_x25519;
S2N_PREPARE_DATA_LENGTH(&key_share_extension);
EXPECT_SUCCESS(s2n_write_key_share(&key_share_extension,
test_curve->iana_id, test_curve->share_size, test_curve));
S2N_WRITE_DATA_LENGTH(&key_share_extension);
EXPECT_SUCCESS(s2n_client_key_share_extension.recv(conn, &key_share_extension));
/* should read all data */
EXPECT_EQUAL(s2n_stuffer_data_available(&key_share_extension), 0);
/* should not have initialized any curves */
struct s2n_ecc_evp_params *ecc_evp_params = &conn->kex_params.client_ecc_evp_params;
EXPECT_NULL(ecc_evp_params->negotiated_curve);
EXPECT_NULL(ecc_evp_params->evp_pkey);
EXPECT_SUCCESS(s2n_stuffer_free(&key_share_extension));
EXPECT_SUCCESS(s2n_connection_free(conn));
EXPECT_SUCCESS(s2n_config_free(config));
}
};
};
END_TEST();
return 0;
}
static int s2n_test_rewrite_length(struct s2n_stuffer *stuffer)
{
POSIX_ENSURE_REF(stuffer);
int length = s2n_stuffer_data_available(stuffer) - S2N_SIZE_OF_CLIENT_SHARE_SIZE;
POSIX_GUARD(s2n_stuffer_rewrite(stuffer));
POSIX_GUARD(s2n_stuffer_write_uint16(stuffer, length));
POSIX_GUARD(s2n_stuffer_skip_write(stuffer, length));
return 0;
}
static int s2n_write_named_curve(struct s2n_stuffer *out,
const struct s2n_ecc_named_curve *existing_curve)
{
return s2n_write_key_share(out, existing_curve->iana_id, existing_curve->share_size, existing_curve);
}
static int s2n_write_key_share(struct s2n_stuffer *out,
uint16_t iana_value, uint16_t share_size,
const struct s2n_ecc_named_curve *existing_curve)
{
POSIX_ENSURE_REF(out);
POSIX_ENSURE_REF(existing_curve);
struct s2n_ecc_evp_params ecc_evp_params;
const struct s2n_ecc_named_curve test_curve = {
.iana_id = iana_value,
.libcrypto_nid = existing_curve->libcrypto_nid,
.name = existing_curve->name,
.share_size = share_size,
.generate_key = existing_curve->generate_key
};
ecc_evp_params.negotiated_curve = &test_curve;
ecc_evp_params.evp_pkey = NULL;
if (s2n_ecdhe_parameters_send(&ecc_evp_params, out) < 0) {
POSIX_GUARD(s2n_ecc_evp_params_free(&ecc_evp_params));
return 1;
}
POSIX_GUARD(s2n_ecc_evp_params_free(&ecc_evp_params));
return 0;
}
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