text: /*
   * 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 <cbmc_proof/nondet.h>
  #include <cbmc_proof/proof_allocators.h>
  
  #include "api/s2n.h"
  #include "crypto/s2n_dhe.h"
  #include "stuffer/s2n_stuffer.h"
  
  /*
   * Since this function largely serves as a way to call specific OpenSSL
   * functions (which we do not fully emulate in CBMC), all we can assert
   * is memory safety. As such, several OpenSSL functions have been stubbed,
   * and a few functions have been left omitted since they do not affect
   * the proof.
   */
  void s2n_pkcs3_to_dh_params_openssl_1_1_0_harness()
  {
      /* Non-deterministic inputs. */
      struct s2n_dh_params *dh_params = cbmc_allocate_dh_params();
      struct s2n_blob *     pkcs3     = cbmc_allocate_s2n_blob();
  
      /* Assumptions. */
      __CPROVER_assume(s2n_blob_is_valid(pkcs3));
      __CPROVER_assume(s2n_blob_is_bounded(pkcs3, MAX_BLOB_SIZE));
      nondet_s2n_mem_init();
  
      /* Save previous state. */
      uint8_t *                     old_data = pkcs3->data;
      struct store_byte_from_buffer old_byte;
      save_byte_from_blob(pkcs3, &old_byte);
  
      /* Operation under verification. */
      if (s2n_pkcs3_to_dh_params(dh_params, pkcs3) == S2N_SUCCESS) {
          /* Postconditions. */
          assert(pkcs3->data == old_data);
          assert_byte_from_blob_matches(pkcs3, &old_byte);
      }
  }
  