joomla_test/libraries/joomla/crypt/cipher/mcrypt.php
2020-01-02 22:20:31 +07:00

176 lines
4.2 KiB
PHP

<?php
/**
* @package Joomla.Platform
* @subpackage Crypt
*
* @copyright Copyright (C) 2005 - 2011 Open Source Matters, Inc. All rights reserved.
* @license GNU General Public License version 2 or later; see LICENSE
*/
defined('JPATH_PLATFORM') or die;
/**
* JCrypt cipher for mcrypt algorithm encryption, decryption and key generation.
*
* @package Joomla.Platform
* @subpackage Crypt
* @since 12.1
*/
abstract class JCryptCipherMcrypt implements JCryptCipher
{
/**
* @var integer The mcrypt cipher constant.
* @see http://www.php.net/manual/en/mcrypt.ciphers.php
* @since 12.1
*/
protected $type;
/**
* @var integer The mcrypt block cipher mode.
* @see http://www.php.net/manual/en/mcrypt.constants.php
* @since 12.1
*/
protected $mode;
/**
* @var string The JCrypt key type for validation.
* @since 12.1
*/
protected $keyType;
/**
* Constructor.
*
* @since 12.1
* @throws RuntimeException
*/
public function __construct()
{
if (!is_callable('mcrypt_encrypt'))
{
throw new RuntimeException('The mcrypt extension is not available.');
}
}
/**
* Method to decrypt a data string.
*
* @param string $data The encrypted string to decrypt.
* @param JCryptKey $key The key object to use for decryption.
*
* @return string The decrypted data string.
*
* @since 12.1
*/
public function decrypt($data, JCryptKey $key)
{
// Validate key.
if ($key->type != $this->keyType)
{
throw new InvalidArgumentException('Invalid key of type: ' . $key->type . '. Expected ' . $this->keyType . '.');
}
// Decrypt the data.
$decrypted = trim(mcrypt_decrypt($this->type, $key->private, $data, $this->mode, $key->public));
return $decrypted;
}
/**
* Method to encrypt a data string.
*
* @param string $data The data string to encrypt.
* @param JCryptKey $key The key object to use for encryption.
*
* @return string The encrypted data string.
*
* @since 12.1
*/
public function encrypt($data, JCryptKey $key)
{
// Validate key.
if ($key->type != $this->keyType)
{
throw new InvalidArgumentException('Invalid key of type: ' . $key->type . '. Expected ' . $this->keyType . '.');
}
// Encrypt the data.
$encrypted = mcrypt_encrypt($this->type, $key->private, $data, $this->mode, $key->public);
return $encrypted;
}
/**
* Method to generate a new encryption key object.
*
* @param array $options Key generation options.
*
* @return JCryptKey
*
* @since 12.1
*/
public function generateKey(array $options = array())
{
// Create the new encryption key object.
$key = new JCryptKey($this->keyType);
// Generate an initialisation vector based on the algorithm.
$key->public = mcrypt_create_iv(mcrypt_get_iv_size($this->type, $this->mode));
// Get the salt and password setup.
$salt = (isset($options['salt'])) ? $options['salt'] : substr(pack("h*", md5(mt_rand())), 0, 16);
$password = (isset($options['password'])) ? $options['password'] : 'J00ml4R0ck$!';
// Generate the derived key.
$key->private = $this->pbkdf2($password, $salt, mcrypt_get_key_size($this->type, $this->mode));
return $key;
}
/**
* PBKDF2 Implementation for deriving keys.
*
* @param string $p Password
* @param string $s Salt
* @param integer $kl Key length
* @param integer $c Iteration count
* @param string $a Hash algorithm
*
* @return string The derived key.
*
* @see http://en.wikipedia.org/wiki/PBKDF2
* @see http://www.ietf.org/rfc/rfc2898.txt
* @since 12.1
*/
public function pbkdf2($p, $s, $kl, $c = 10000, $a = 'sha256')
{
// Hash length.
$hl = strlen(hash($a, null, true));
// Key blocks to compute.
$kb = ceil($kl / $hl);
// Derived key.
$dk = '';
// Create the key.
for ($block = 1; $block <= $kb; $block++)
{
// Initial hash for this block.
$ib = $b = hash_hmac($a, $s . pack('N', $block), $p, true);
// Perform block iterations.
for ($i = 1; $i < $c; $i++)
{
$ib ^= ($b = hash_hmac($a, $b, $p, true));
}
// Append the iterated block.
$dk .= $ib;
}
// Return derived key of correct length.
return substr($dk, 0, $kl);
}
}