[Summary view] [Print] [Text view]

   1  <?php
   2  /**
   3   * Random_* Compatibility Library
   4   * for using the new PHP 7 random_* API in PHP 5 projects
   5   *
   6   * The MIT License (MIT)
   7   *
   8   * Copyright (c) 2015 - 2018 Paragon Initiative Enterprises
   9   *
  10   * Permission is hereby granted, free of charge, to any person obtaining a copy
  11   * of this software and associated documentation files (the "Software"), to deal
  12   * in the Software without restriction, including without limitation the rights
  13   * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  14   * copies of the Software, and to permit persons to whom the Software is
  15   * furnished to do so, subject to the following conditions:
  16   *
  17   * The above copyright notice and this permission notice shall be included in
  18   * all copies or substantial portions of the Software.
  19   *
  20   * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  21   * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  22   * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  23   * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  24   * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  25   * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  26   * SOFTWARE.
  27   */
  28  
  29  if (!is_callable('random_bytes')) {
  30      /**
  31       * Powered by ext/mcrypt (and thankfully NOT libmcrypt)
  32       *
  33       * @ref https://bugs.php.net/bug.php?id=55169
  34       * @ref https://github.com/php/php-src/blob/c568ffe5171d942161fc8dda066bce844bdef676/ext/mcrypt/mcrypt.c#L1321-L1386
  35       *
  36       * @param int $bytes
  37       *
  38       * @throws Exception
  39       *
  40       * @return string
  41       */
  42      function random_bytes($bytes)
  43      {
  44          try {
  45              /** @var int $bytes */
  46              $bytes = RandomCompat_intval($bytes);
  47          } catch (TypeError $ex) {
  48              throw new TypeError(
  49                  'random_bytes(): $bytes must be an integer'
  50              );
  51          }
  52  
  53          if ($bytes < 1) {
  54              throw new Error(
  55                  'Length must be greater than 0'
  56              );
  57          }
  58  
  59          /** @var string|bool $buf */
  60          $buf = @mcrypt_create_iv((int) $bytes, (int) MCRYPT_DEV_URANDOM);
  61          if (
  62              is_string($buf)
  63                  &&
  64              RandomCompat_strlen($buf) === $bytes
  65          ) {
  66              /**
  67               * Return our random entropy buffer here:
  68               */
  69              return $buf;
  70          }
  71  
  72          /**
  73           * If we reach here, PHP has failed us.
  74           */
  75          throw new Exception(
  76              'Could not gather sufficient random data'
  77          );
  78      }
  79  }