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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.
*/
/* Target Functions: s2n_client_cert_recv s2n_x509_validator_validate_cert_chain */
#include <errno.h>
#include <fcntl.h>
#include <stddef.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <openssl/crypto.h>
#include <openssl/err.h>
#include "api/s2n.h"
#include "stuffer/s2n_stuffer.h"
#include "tls/s2n_cipher_suites.h"
#include "tls/s2n_config.h"
#include "tls/s2n_connection.h"
#include "tls/s2n_crypto.h"
#include "tls/s2n_tls.h"
#include "tls/s2n_tls_parameters.h"
#include "utils/s2n_random.h"
#include "utils/s2n_safety.h"
#include "s2n_test.h"
#include "testlib/s2n_testlib.h"
struct host_verify_data {
const char *name;
uint8_t found_name;
uint8_t callback_invoked;
};
static uint8_t verify_host_accept_everything(const char *host_name, size_t host_name_len, void *data)
{
struct host_verify_data *verify_data = (struct host_verify_data *) data;
verify_data->callback_invoked = 1;
return 1;
}
static const uint8_t TLS_VERSIONS[] = {S2N_TLS10, S2N_TLS11, S2N_TLS12, S2N_TLS13};
int s2n_fuzz_test(const uint8_t *buf, size_t len)
{
/* We need at least one byte of input to set parameters */
S2N_FUZZ_ENSURE_MIN_LEN(len, 1);
/* Setup */
struct host_verify_data verify_data = { .callback_invoked = 0, .found_name = 0, .name = NULL };
struct s2n_x509_trust_store trust_store;
struct s2n_connection *server_conn = s2n_connection_new(S2N_SERVER);
POSIX_ENSURE_REF(server_conn);
POSIX_GUARD(s2n_stuffer_write_bytes(&server_conn->handshake.io, buf, len));
/* Returns void, so can't be guarded */
s2n_x509_trust_store_init_empty(&trust_store);
/* Pull a byte off the libfuzzer input and use it to set parameters */
uint8_t randval = 0;
POSIX_GUARD(s2n_stuffer_read_uint8(&server_conn->handshake.io, &randval));
if(randval % 2) {
POSIX_GUARD(s2n_x509_trust_store_from_ca_file(&trust_store, S2N_DEFAULT_TEST_CERT_CHAIN, NULL));
POSIX_GUARD(s2n_connection_set_verify_host_callback(server_conn, verify_host_accept_everything, &verify_data));
}
/* Returns void, so can't be guarded */
s2n_x509_validator_wipe(&server_conn->x509_validator);
POSIX_GUARD(s2n_x509_validator_init(&server_conn->x509_validator, &trust_store, 1));
server_conn->x509_validator.skip_cert_validation = (randval >> 1) % 2;
server_conn->actual_protocol_version = TLS_VERSIONS[((randval >> 4) & 0x0f) % s2n_array_len(TLS_VERSIONS)];
/* Run Test
* Do not use GUARD macro here since the connection memory hasn't been freed.
*/
s2n_client_cert_recv(server_conn);
/* Cleanup */
/* Returns void, so can't be guarded */
s2n_x509_trust_store_wipe(&trust_store);
s2n_x509_validator_wipe(&server_conn->x509_validator);
POSIX_GUARD(s2n_connection_free(server_conn));
return S2N_SUCCESS;
}
S2N_FUZZ_TARGET(NULL, s2n_fuzz_test, NULL)
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