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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 <assert.h>
#include <cbmc_proof/cbmc_utils.h>
#include <cbmc_proof/make_common_datastructures.h>
#include "api/s2n.h"
#include "utils/s2n_blob.h"
void s2n_free_harness()
{
/* Non-deterministic inputs. */
struct s2n_blob *blob = cbmc_allocate_s2n_blob();
/* Assumptions. */
nondet_s2n_mem_init();
__CPROVER_assume(s2n_result_is_ok(s2n_blob_validate(blob)));
const struct s2n_blob old_blob = *blob;
/* Operation under verification. */
int result = s2n_free(blob);
if (result == S2N_SUCCESS) {
/* Postconditions. */
assert(S2N_IMPLIES(old_blob.allocated, blob->data == NULL));
assert_all_zeroes((const uint8_t *)blob, sizeof(*blob));
if (old_blob.size != 0 && s2n_blob_is_growable(&old_blob)) {
assert(!S2N_MEM_IS_READABLE(blob->data, old_blob.size));
}
}
/* Cleanup after expected error cases, for memory leak check. */
bool failed_before_free = (s2n_errno == S2N_ERR_NOT_INITIALIZED) || (s2n_errno == S2N_ERR_FREE_STATIC_BLOB);
if ((result != S2N_SUCCESS && failed_before_free) || !s2n_blob_is_growable(blob)) {
/* 1. `s2n_free` failed _before_ calling `free`, either because:
(a) s2n was not initialized, or (b) the blob was a static blob.
2. `blob` is not growable, then `s2n_free` is not supposed to `free` even if successful.
*/
free(blob->data);
}
/* 3. free our heap-allocated `blob` since `s2n_free` only `free`s the contents. */
free(blob);
}
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