interface/modules/zend_modules/library/Zend/Crypt/Hash.php

   1 <?php
   2 /**
   3  * Zend Framework (http://framework.zend.com/)
   4  *
   5  * @link      http://github.com/zendframework/zf2 for the canonical source repository
   6  * @copyright Copyright (c) 2005-2013 Zend Technologies USA Inc. (http://www.zend.com)
   7  * @license   http://framework.zend.com/license/new-bsd New BSD License
   8  */
   9
  10 namespace Zend\Crypt;
  11
  12 class Hash
  13 {
  14     const OUTPUT_STRING = false;
  15     const OUTPUT_BINARY = true;
  16
  17     /**
  18      * Last algorithm supported
  19      *
  20      * @var string|null
  21      */
  22     protected static $lastAlgorithmSupported;
  23
  24     /**
  25      * @param  string  $hash
  26      * @param  string  $data
  27      * @param  bool $output
  28      * @throws Exception\InvalidArgumentException
  29      * @return string
  30      */
  31     public static function compute($hash, $data, $output = self::OUTPUT_STRING)
  32     {
  33         if (!$hash || ($hash !== static::$lastAlgorithmSupported && !static::isSupported($hash))) {
  34             throw new Exception\InvalidArgumentException(
  35                 'Hash algorithm provided is not supported on this PHP installation'
  36             );
  37         }
  38
  39         return hash($hash, $data, $output);
  40     }
  41
  42     /**
  43      * Get the output size according to the hash algorithm and the output format
  44      *
  45      * @param  string  $hash
  46      * @param  bool $output
  47      * @return int
  48      */
  49     public static function getOutputSize($hash, $output = self::OUTPUT_STRING)
  50     {
  51         return strlen(static::compute($hash, 'data', $output));
  52     }
  53
  54     /**
  55      * Get the supported algorithm
  56      *
  57      * @return array
  58      */
  59     public static function getSupportedAlgorithms()
  60     {
  61         return hash_algos();
  62     }
  63
  64     /**
  65      * Is the hash algorithm supported?
  66      *
  67      * @param  string $algorithm
  68      * @return bool
  69      */
  70     public static function isSupported($algorithm)
  71     {
  72         if ($algorithm === static::$lastAlgorithmSupported) {
  73             return true;
  74         }
  75
  76         if (in_array(strtolower($algorithm), hash_algos(), true)) {
  77             static::$lastAlgorithmSupported = $algorithm;
  78             return true;
  79         }
  80
  81         return false;
  82     }
  83
  84     /**
  85      * Clear the cache of last algorithm supported
  86      */
  87     public static function clearLastAlgorithmCache()
  88     {
  89         static::$lastAlgorithmSupported = null;
  90     }
  91 }