vendor/paragonie/random_compat/lib/random_bytes_com_dotnet.php

   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      * Windows with PHP < 5.3.0 will not have the function
  32      * openssl_random_pseudo_bytes() available, so let's use
  33      * CAPICOM to work around this deficiency.
  34      *
  35      * @param int $bytes
  36      *
  37      * @throws Exception
  38      *
  39      * @return string
  40      */
  41     function random_bytes($bytes)
  42     {
  43         try {
  44             $bytes = RandomCompat_intval($bytes);
  45         } catch (TypeError $ex) {
  46             throw new TypeError(
  47                 'random_bytes(): $bytes must be an integer'
  48             );
  49         }
  50
  51         if ($bytes < 1) {
  52             throw new Error(
  53                 'Length must be greater than 0'
  54             );
  55         }
  56
  57         $buf = '';
  58         if (!class_exists('COM')) {
  59             throw new Error(
  60                 'COM does not exist'
  61             );
  62         }
  63         $util = new COM('CAPICOM.Utilities.1');
  64         $execCount = 0;
  65
  66         /**
  67          * Let's not let it loop forever. If we run N times and fail to
  68          * get N bytes of random data, then CAPICOM has failed us.
  69          */
  70         do {
  71             $buf .= base64_decode($util->GetRandom($bytes, 0));
  72             if (RandomCompat_strlen($buf) >= $bytes) {
  73                 /**
  74                  * Return our random entropy buffer here:
  75                  */
  76                 return RandomCompat_substr($buf, 0, $bytes);
  77             }
  78             ++$execCount;
  79         } while ($execCount < $bytes);
  80
  81         /**
  82          * If we reach here, PHP has failed us.
  83          */
  84         throw new Exception(
  85             'Could not gather sufficient random data'
  86         );
  87     }
  88 }