CryptLib/Random/Source/CAPICOM.php

   1 <?php
   2 /**
   3  * The Capicom Random Number Source
   4  *
   5  * This uses the Windows CapiCom Com object to generate random numbers
   6  *
   7  * PHP version 5.3
   8  *
   9  * @category   PHPCryptLib
  10  * @package    Random
  11  * @subpackage Source
  12  * @author     Anthony Ferrara <ircmaxell@ircmaxell.com>
  13  * @copyright  2011 The Authors
  14  * @license    http://www.opensource.org/licenses/mit-license.html  MIT License
  15  * @version    Build @@version@@
  16  */
  17
  18 namespace CryptLib\Random\Source;
  19
  20 use CryptLib\Core\Strength;
  21
  22 /**
  23  * The Capicom Random Number Source
  24  *
  25  * This uses the Windows CapiCom Com object to generate random numbers
  26  *
  27  * @category   PHPCryptLib
  28  * @package    Random
  29  * @subpackage Source
  30  * @author     Anthony Ferrara <ircmaxell@ircmaxell.com>
  31  * @codeCoverageIgnore
  32  */
  33 class CAPICOM implements \CryptLib\Random\Source {
  34
  35     /**
  36      * Return an instance of Strength indicating the strength of the source
  37      *
  38      * @return Strength An instance of one of the strength classes
  39      */
  40     public static function getStrength() {
  41         return new Strength(Strength::MEDIUM);
  42     }
  43
  44     /**
  45      * Generate a random string of the specified size
  46      *
  47      * @param int $size The size of the requested random string
  48      *
  49      * @return string A string of the requested size
  50      */
  51     public function generate($size) {
  52         if (!class_exists('\\COM', false)) {
  53             return str_repeat(chr(0), $size);
  54         }
  55         try {
  56             $util = new \COM('CAPICOM.Utilities.1');
  57             $data = base64_decode($util->GetRandom($size, 0));
  58             return str_pad($data, $size, chr(0));
  59         } catch (\Exception $e) {
  60             unset($e);
  61             return str_repeat(chr(0), $size);
  62         }
  63     }
  64
  65 }