/*

# Copyright 2016 Google Inc.

# Copyright 2017 Red Hat, Inc.

#

# Licensed under the Apache License, Version 2.0 (the "License");

# you may not use this file except in compliance with the License.

# You may obtain a copy of the License at

#

#      https://www.apache.org/licenses/LICENSE-2.0

#

# Unless required by applicable law or agreed to in writing, software

# distributed under the License 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 <fcntl.h>

#include <stdint.h>

#include <sys/types.h>

#include <unistd.h>

#include <string.h>

#include <stdlib.h>

#include <stdbool.h>

#include <gnutls/crypto.h>

#include <gnutls/gnutls.h>

#include "handshake.h"

#include "fuzzer.h"

int __attribute__((visibility("protected")))

gnutls_rnd(gnutls_rnd_level_t level, void *data, size_t len)

{

  memset(data, 0xff, len);

  /* Flip the first byte to avoid infinite loop in the RSA

   * blinding code of Nettle */

  if (len > 0)

    memset(data, 0x0, 1);

  return 0;

}

int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size)

{

  int res;

  gnutls_session_t session;

  gnutls_certificate_credentials_t xcred;

  struct mem_st memdata;

  unsigned int retry;

  res = gnutls_init(&session, GNUTLS_CLIENT);

  assert(res >= 0);

  res = gnutls_certificate_allocate_credentials(&xcred);

  assert(res >= 0);

  res = gnutls_credentials_set(session, GNUTLS_CRD_CERTIFICATE, xcred);

  assert(res >= 0);

  /*res = gnutls_set_default_priority(session); */

  res = gnutls_priority_set_direct(

    session, "NORMAL:-VERS-TLS-ALL:+VERS-TLS1.3", NULL);

  assert(res >= 0);

  memdata.data = data;

  memdata.size = size;

  gnutls_transport_set_push_function(session, error_push);

  gnutls_transport_set_pull_function(session, error_pull);

  gnutls_handshake_set_read_function(session, handshake_discard);

  retry = 0;

  do {

    res = gnutls_handshake(session);

    if (res == GNUTLS_E_AGAIN) {

      if (handshake_pull(session, &memdata) < 0) {

        res = GNUTLS_E_INTERNAL_ERROR;

        break;

      }

      if (retry > HANDSHAKE_MAX_RETRY_COUNT) {

        break;

      }

      retry++;

    } else {

      retry = 0;

    }

  } while (res < 0 && gnutls_error_is_fatal(res) == 0);

  gnutls_deinit(session);

  gnutls_certificate_free_credentials(xcred);

  return 0;

}