<?php
/*
* MODX Revolution
*
* Copyright 2006-2014 by MODX, LLC.
* All rights reserved.
*
* This program is free software; you can redistribute it and/or modify it under
* the terms of the GNU General Public License as published by the Free Software
* Foundation; either version 2 of the License, or (at your option) any later
* version.
*
* This program is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
* FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
* details.
*
* You should have received a copy of the GNU General Public License along with
* this program; if not, write to the Free Software Foundation, Inc., 59 Temple
* Place, Suite 330, Boston, MA 02111-1307 USA
*/
/**
* This file contains the modHashing service class definition and the modHash abstract implementation class.
* @package modx
* @subpackage hashing
*/
/**
* The modX hashing service class.
*
* @package modx
* @subpackage hashing
*/
class modHashing {
/**
* A reference to an xPDO instance communicating with this service instance.
*
* Though this is typically a modX instance, an xPDO instance must work for new installs.
* @var xPDO
*/
public $modx= null;
/**
* An array of options for the hashing service.
* @var array
*/
public $options= array();
/**
* An array of loaded modHash implementations.
* @var array
*/
protected $_hashes= array();
/**
* Constructs a new instance of the modHashing service class.
*
* @param xPDO &$modx A reference to an modX (or xPDO) instance.
* @param array|null $options An array of options for the hashing service.
*/
function __construct(xPDO &$modx, $options= array()) {
$this->modx= & $modx;
if (is_array($options)) {
$this->options = $options;
}
}
/**
* Get an option for the MODX hashing service.
*
* Searches for local options and then prefixes keys with encrypt_ to look for
* MODX System Settings.
*
* @param string $key The option key to get a value for.
* @param array|null $options An optional array of options to look in first.
* @param mixed $default An optional default value to return if no value is set.
* @return mixed The option value or the specified default if not found.
*/
public function getOption($key, $options = null, $default = null) {
if (is_array($options) && array_key_exists($key, $options)) {
$option = $options[$key];
} elseif (array_key_exists($key, $this->options)) {
$option = $this->options[$key];
} else {
$option = $this->modx->getOption('hashing_' . $key, $this->options, $default);
}
return $option;
}
/**
* Get a hash implementation instance.
*
* The implementation is made available as a member variable of the modHashing service.
*
* @param string $key A key string identifying the instance; must be a valid PHP variable name.
* @param string $class A valid fully-qualified modHash derivative class name
* @param array|null $options An optional array of hash options.
* @return modHash|null A reference to a modHash instance or null if could not be instantiated.
*/
public function getHash($key, $class, $options = array()) {
$className = $this->modx->loadClass($class, '', false, true);
if ($className) {
if (empty($key)) $key = strtolower(str_replace('mod', '', $className));
if (!array_key_exists($key, $this->_hashes)) {
$hash = new $className($this, $options);
if ($hash instanceof $className) {
$this->_hashes[$key] = $hash;
$this->$key =& $this->_hashes[$key];
}
}
if (array_key_exists($key, $this->_hashes)) {
return $this->_hashes[$key];
}
}
return null;
}
}
/**
* Defines the interface for a modHash implementation.
*
* @abstract Implement a derivative of this class to define an actual hash algorithm implementation.
* @package modx
* @subpackage hashing
*/
abstract class modHash {
/**
* A reference to the modHashing service hosting this modHash instance.
* @var modHashing
*/
public $host= null;
/**
* An array of options for the modHash implementation.
* @var array
*/
public $options= array();
/**
* Constructs a new instance of the modHash class.
*
* @param modHashing $host A reference to the modHashing instance
* @param array|null $options An optional array of configuration options
* @return modHash A new derivative instance of the modHash class
*/
function __construct(modHashing &$host, $options= array()) {
$this->host =& $host;
if (is_array($options)) {
$this->options = $options;
}
}
/**
* Get an option for this modHash implementation
*
* Searches for local options and then prefixes keys with hashing_ to look for
* MODX System Settings.
*
* @param string $key The option key to get a value for.
* @param array|null $options An optional array of options to look in first.
* @param mixed $default An optional default value to return if no value is set.
* @return mixed The option value or the specified default if not found.
*/
public function getOption($key, $options = null, $default = null) {
if (is_array($options) && array_key_exists($key, $options)) {
$option = $options[$key];
} else {
$option = $this->host->getOption($key, $this->options, $default);
}
return $option;
}
/**
* Generate a hash of the given string using the provided options.
*
* @abstract
* @param string $string A string to generate a secure hash from.
* @param array $options An array of options to be passed to the hash implementation.
* @return mixed The hash result or false on failure.
*/
public abstract function hash($string, array $options = array());
}