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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_tls13_cert_verify_recv s2n_get_and_validate_negotiated_signature_scheme
s2n_tls13_cert_read_and_verify_signature */
#include <stdint.h>
#include <openssl/crypto.h>
#include <openssl/err.h>
#include "api/s2n.h"
#include "stuffer/s2n_stuffer.h"
#include "tls/s2n_connection.h"
#include "tls/s2n_tls.h"
#include "utils/s2n_safety.h"
#include "s2n_test.h"
#include "testlib/s2n_testlib.h"
uint8_t *cert_chain = NULL;
uint8_t *private_key = NULL;
uint32_t cert_chain_len = 0;
uint32_t private_key_len = 0;
struct s2n_cert_chain_and_key *default_cert;
struct s2n_config *conn_config;
int s2n_fuzz_init(int *argc, char **argv[])
{
/* Initialize test chain and key */
cert_chain = malloc(S2N_MAX_TEST_PEM_SIZE);
POSIX_ENSURE_REF(cert_chain);
private_key = malloc(S2N_MAX_TEST_PEM_SIZE);
POSIX_ENSURE_REF(private_key);
default_cert = s2n_cert_chain_and_key_new();
POSIX_ENSURE_REF(default_cert);
conn_config = s2n_config_new();
POSIX_ENSURE_REF(conn_config);
POSIX_GUARD(s2n_read_test_pem_and_len(S2N_DEFAULT_TEST_CERT_CHAIN, cert_chain, &cert_chain_len, S2N_MAX_TEST_PEM_SIZE));
POSIX_GUARD(s2n_read_test_pem_and_len(S2N_DEFAULT_TEST_PRIVATE_KEY, private_key, &private_key_len, S2N_MAX_TEST_PEM_SIZE));
POSIX_GUARD(s2n_cert_chain_and_key_load_pem_bytes(default_cert, cert_chain, cert_chain_len, private_key, private_key_len));
POSIX_GUARD(s2n_config_add_cert_chain_and_key_to_store(conn_config, default_cert));
return S2N_SUCCESS;
}
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 s2n_connection *conn = s2n_connection_new(S2N_SERVER);
POSIX_ENSURE_REF(conn);
POSIX_GUARD(s2n_connection_set_config(conn, conn_config));
POSIX_GUARD(s2n_stuffer_write_bytes(&conn->handshake.io, buf, len));
/* Pull a byte off the libfuzzer input and use it to set the connection mode */
uint8_t randval = 0;
POSIX_GUARD(s2n_stuffer_read_uint8(&conn->handshake.io, &randval));
if (randval % 2) {
conn->mode = S2N_CLIENT;
}
/* Run Test
* Do not use GUARD macro here since the connection memory hasn't been freed.
*/
s2n_tls13_cert_verify_recv(conn);
/* Cleanup */
POSIX_GUARD(s2n_connection_free(conn));
return S2N_SUCCESS;
}
static void s2n_fuzz_cleanup()
{
s2n_config_free(conn_config);
free(cert_chain);
free(private_key);
s2n_cert_chain_and_key_free(default_cert);
}
S2N_FUZZ_TARGET(s2n_fuzz_init, s2n_fuzz_test, s2n_fuzz_cleanup)
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