gnu-social/plugins/OStatus/extlib/Crypt/RSA/MathLoader.php

136 lines
4.9 KiB
PHP
Raw Normal View History

2010-02-22 23:05:32 +09:00
<?php
/**
* Crypt_RSA allows to do following operations:
* - key pair generation
* - encryption and decryption
* - signing and sign validation
*
* PHP versions 4 and 5
*
* LICENSE: This source file is subject to version 3.0 of the PHP license
* that is available through the world-wide-web at the following URI:
* http://www.php.net/license/3_0.txt. If you did not receive a copy of
* the PHP License and are unable to obtain it through the web, please
* send a note to license@php.net so we can mail you a copy immediately.
*
* @category Encryption
* @package Crypt_RSA
* @author Alexander Valyalkin <valyala@gmail.com>
* @copyright Alexander Valyalkin 2005
* @license http://www.php.net/license/3_0.txt PHP License 3.0
* @version CVS: $Id: MathLoader.php,v 1.5 2009/01/05 08:30:29 clockwerx Exp $
* @link http://pear.php.net/package/Crypt_RSA
*/
/**
* RSA error handling facilities
*/
require_once 'Crypt/RSA/ErrorHandler.php';
/**
* Crypt_RSA_MathLoader class.
*
* Provides static function:
* - loadWrapper($wrapper_name) - loads RSA math wrapper with name $wrapper_name
* or most suitable wrapper if $wrapper_name == 'default'
*
* Example usage:
* // load BigInt wrapper
* $big_int_wrapper = Crypt_RSA_MathLoader::loadWrapper('BigInt');
*
* // load BCMath wrapper
* $bcmath_wrapper = Crypt_RSA_MathLoader::loadWrapper('BCMath');
*
* // load the most suitable wrapper
* $bcmath_wrapper = Crypt_RSA_MathLoader::loadWrapper();
*
* @category Encryption
* @package Crypt_RSA
* @author Alexander Valyalkin <valyala@gmail.com>
* @copyright Alexander Valyalkin 2005
* @license http://www.php.net/license/3_0.txt PHP License 3.0
* @version Release: @package_version@
* @link http://pear.php.net/package/Crypt_RSA
* @access public
*/
class Crypt_RSA_MathLoader
{
/**
* Loads RSA math wrapper with name $wrapper_name.
* Implemented wrappers can be found at Crypt/RSA/Math folder.
* Read docs/Crypt_RSA/docs/math_wrappers.txt for details
*
* This is a static function:
* // load BigInt wrapper
* $big_int_wrapper = &Crypt_RSA_MathLoader::loadWrapper('BigInt');
*
* // load BCMath wrapper
* $bcmath_wrapper = &Crypt_RSA_MathLoader::loadWrapper('BCMath');
*
* @param string $wrapper_name Name of wrapper
*
* @return object
* Reference to object of wrapper with name $wrapper_name on success
* or PEAR_Error object on error
*
* @access public
*/
function loadWrapper($wrapper_name = 'default')
{
static $math_objects = array();
// ordered by performance. GMP is the fastest math library, BCMath - the slowest.
static $math_wrappers = array('GMP', 'BigInt', 'BCMath',);
if (isset($math_objects[$wrapper_name])) {
/*
wrapper with name $wrapper_name is already loaded and created.
Return reference to existing copy of wrapper
*/
return $math_objects[$wrapper_name];
}
$err_handler = new Crypt_RSA_ErrorHandler();
if ($wrapper_name === 'default') {
// try to load the most suitable wrapper
$n = sizeof($math_wrappers);
for ($i = 0; $i < $n; $i++) {
$obj = Crypt_RSA_MathLoader::loadWrapper($math_wrappers[$i]);
if (!$err_handler->isError($obj)) {
// wrapper for $math_wrappers[$i] successfully loaded
// register it as default wrapper and return reference to it
return $math_objects['default'] = $obj;
}
}
// can't load any wrapper
$err_handler->pushError("can't load any wrapper for existing math libraries", CRYPT_RSA_ERROR_NO_WRAPPERS);
return $err_handler->getLastError();
}
$class_name = 'Crypt_RSA_Math_' . $wrapper_name;
$class_filename = dirname(__FILE__) . '/Math/' . $wrapper_name . '.php';
if (!is_file($class_filename)) {
$err_handler->pushError("can't find file [{$class_filename}] for RSA math wrapper [{$wrapper_name}]", CRYPT_RSA_ERROR_NO_FILE);
return $err_handler->getLastError();
}
include_once $class_filename;
if (!class_exists($class_name)) {
$err_handler->pushError("can't find class [{$class_name}] in file [{$class_filename}]", CRYPT_RSA_ERROR_NO_CLASS);
return $err_handler->getLastError();
}
// create and return wrapper object on success or PEAR_Error object on error
$obj = new $class_name;
if ($obj->errstr) {
// cannot load required extension for math wrapper
$err_handler->pushError($obj->errstr, CRYPT_RSA_ERROR_NO_EXT);
return $err_handler->getLastError();
}
return $math_objects[$wrapper_name] = $obj;
}
}
?>