[Sommaire] [Imprimer]

   1  <?php
   2  /**
   3   * The Horde_Cipher:: class provides a common abstracted interface to
   4   * various Ciphers for encryption of arbitrary length pieces of data.
   5   *
   6   * Copyright 2002-2006 Mike Cochrane <mike@graftonhall.co.nz>
   7   *
   8   * See the enclosed file COPYING for license information (LGPL). If you
   9   * did not receive this file, see http://www.fsf.org/copyleft/lgpl.html.
  10   *
  11   * $Horde: framework/Cipher/Cipher.php,v 1.16.12.8 2006/01/01 21:28:10 jan Exp $
  12   *
  13   * @author  Mike Cochrane <mike@graftonhall.co.nz>
  14   * @since   Horde 2.2
  15   * @package Horde_Cipher
  16   */
  17  class Horde_Cipher {
  18  
  19      /**
  20       * The block mode for the cipher chaining
  21       *
  22       * @var string
  23       */
  24      var $_blockMode = 'CBC';
  25  
  26      /**
  27       * The initialization vector
  28       *
  29       * @var string
  30       */
  31      var $_iv = null;
  32  
  33      /**
  34       * Set the block mode for cipher chaining.
  35       *
  36       * @param string $blockMode  The new blockmode.
  37       */
  38      function setBlockMode($blockMode)
  39      {
  40          $this->_blockMode = $blockMode;
  41      }
  42  
  43      /**
  44       * Set the IV.
  45       *
  46       * @param string $iv  The new IV.
  47       */
  48      function setIV($iv)
  49      {
  50          $this->_iv = $iv;
  51      }
  52  
  53      /**
  54       * Encrypt a string.
  55       *
  56       * @param string $plaintext  The data to encrypt.
  57       *
  58       * @return string  The encrypted data.
  59       */
  60      function encrypt($plaintext)
  61      {
  62          require_once dirname(__FILE__) . '/Cipher/BlockMode.php';
  63          $blockMode = &Horde_Cipher_BlockMode::factory($this->_blockMode);
  64          if (!is_null($this->_iv)) {
  65              $blockMode->setIV($this->_iv);
  66          }
  67  
  68          return $blockMode->encrypt($this, $plaintext);
  69      }
  70  
  71      /**
  72       * Decrypt a string.
  73       *
  74       * @param string $ciphertext  The data to decrypt.
  75       *
  76       * @return string  The decrypted data.
  77       */
  78      function decrypt($ciphertext)
  79      {
  80          require_once dirname(__FILE__) . '/Cipher/BlockMode.php';
  81          $blockMode = &Horde_Cipher_BlockMode::factory($this->_blockMode);
  82          if (!is_null($this->_iv)) {
  83              $blockMode->setIV($this->_iv);
  84          }
  85  
  86          return $blockMode->decrypt($this, $ciphertext);
  87      }
  88  
  89      /**
  90       * Attempts to return a concrete Horde_Cipher instance.
  91       *
  92       * @param string $cipher  The type of concrete Horde_Cipher subclass to
  93       *                        return.
  94       * @param array $params   A hash containing any additional parameters a
  95       *                        subclass might need.
  96       *
  97       * @return Horde_Cipher  The newly created concrete Horde_Cipher instance,
  98       *                       or PEAR_Error on error.
  99       */
 100      function &factory($cipher, $params = null)
 101      {
 102          $driver = basename($cipher);
 103  
 104          if (@file_exists(dirname(__FILE__) . '/Cipher/' . $cipher . '.php')) {
 105              require_once dirname(__FILE__) . '/Cipher/' . $cipher . '.php';
 106          }
 107  
 108          $class = 'Horde_Cipher_' . $cipher;
 109          if (class_exists($class)) {
 110              $cipher = &new $class($params);
 111          } else {
 112              $cipher = PEAR::raiseError('Class definition of ' . $class . ' not found.');
 113          }
 114  
 115          return $cipher;
 116      }
 117  
 118  }