130 lines
No EOL
4.6 KiB
PHP
Executable file
130 lines
No EOL
4.6 KiB
PHP
Executable file
<?php
|
|
/* vim: set expandtab tabstop=4 shiftwidth=4 softtabstop=4: */
|
|
|
|
/**
|
|
* Random Number Generator
|
|
*
|
|
* PHP versions 4 and 5
|
|
*
|
|
* Here's a short example of how to use this library:
|
|
* <code>
|
|
* <?php
|
|
* include('Crypt/Random.php');
|
|
*
|
|
* echo crypt_random();
|
|
* ?>
|
|
* </code>
|
|
*
|
|
* LICENSE: This library is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU Lesser General Public
|
|
* License as published by the Free Software Foundation; either
|
|
* version 2.1 of the License, or (at your option) any later version.
|
|
*
|
|
* This library 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
|
|
* Lesser General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU Lesser General Public
|
|
* License along with this library; if not, write to the Free Software
|
|
* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
|
|
* MA 02111-1307 USA
|
|
*
|
|
* @category Crypt
|
|
* @package Crypt_Random
|
|
* @author Jim Wigginton <terrafrost@php.net>
|
|
* @copyright MMVII Jim Wigginton
|
|
* @license http://www.gnu.org/licenses/lgpl.txt
|
|
* @version $Id: Random.php,v 1.9 2010/04/24 06:40:48 terrafrost Exp $
|
|
* @link http://phpseclib.sourceforge.net
|
|
*/
|
|
|
|
/**
|
|
* Generate a random value.
|
|
*
|
|
* On 32-bit machines, the largest distance that can exist between $min and $max is 2**31.
|
|
* If $min and $max are farther apart than that then the last ($max - range) numbers.
|
|
*
|
|
* Depending on how this is being used, it may be worth while to write a replacement. For example,
|
|
* a PHP-based web app that stores its data in an SQL database can collect more entropy than this function
|
|
* can.
|
|
*
|
|
* @param optional Integer $min
|
|
* @param optional Integer $max
|
|
* @return Integer
|
|
* @access public
|
|
*/
|
|
function crypt_random($min = 0, $max = 0x7FFFFFFF)
|
|
{
|
|
if ($min == $max) {
|
|
return $min;
|
|
}
|
|
|
|
// see http://en.wikipedia.org/wiki//dev/random
|
|
// if open_basedir is enabled file_exists() will ouput an "open_basedir restriction in effect" warning,
|
|
// so we suppress it.
|
|
if (@file_exists('/dev/urandom')) {
|
|
static $fp;
|
|
if (!$fp) {
|
|
$fp = fopen('/dev/urandom', 'rb');
|
|
}
|
|
extract(unpack('Nrandom', fread($fp, 4)));
|
|
|
|
// say $min = 0 and $max = 3. if we didn't do abs() then we could have stuff like this:
|
|
// -4 % 3 + 0 = -1, even though -1 < $min
|
|
return abs($random) % ($max - $min) + $min;
|
|
}
|
|
|
|
/* Prior to PHP 4.2.0, mt_srand() had to be called before mt_rand() could be called.
|
|
Prior to PHP 5.2.6, mt_rand()'s automatic seeding was subpar, as elaborated here:
|
|
|
|
http://www.suspekt.org/2008/08/17/mt_srand-and-not-so-random-numbers/
|
|
|
|
The seeding routine is pretty much ripped from PHP's own internal GENERATE_SEED() macro:
|
|
|
|
http://svn.php.net/viewvc/php/php-src/branches/PHP_5_3_2/ext/standard/php_rand.h?view=markup */
|
|
if (version_compare(PHP_VERSION, '5.2.5', '<=')) {
|
|
static $seeded;
|
|
if (!isset($seeded)) {
|
|
$seeded = true;
|
|
mt_srand(fmod(time() * getmypid(), 0x7FFFFFFF) ^ fmod(1000000 * lcg_value(), 0x7FFFFFFF));
|
|
}
|
|
}
|
|
|
|
static $crypto;
|
|
|
|
// The CSPRNG's Yarrow and Fortuna periodically reseed. This function can be reseeded by hitting F5
|
|
// in the browser and reloading the page.
|
|
|
|
if (!isset($crypto)) {
|
|
$key = $iv = '';
|
|
for ($i = 0; $i < 8; $i++) {
|
|
$key.= pack('n', mt_rand(0, 0xFFFF));
|
|
$iv .= pack('n', mt_rand(0, 0xFFFF));
|
|
}
|
|
switch (true) {
|
|
case class_exists('Crypt_AES'):
|
|
$crypto = new Crypt_AES(CRYPT_AES_MODE_CTR);
|
|
break;
|
|
case class_exists('Crypt_TripleDES'):
|
|
$crypto = new Crypt_TripleDES(CRYPT_DES_MODE_CTR);
|
|
break;
|
|
case class_exists('Crypt_DES'):
|
|
$crypto = new Crypt_DES(CRYPT_DES_MODE_CTR);
|
|
break;
|
|
case class_exists('Crypt_RC4'):
|
|
$crypto = new Crypt_RC4();
|
|
break;
|
|
default:
|
|
extract(unpack('Nrandom', pack('H*', sha1(mt_rand(0, 0x7FFFFFFF)))));
|
|
return abs($random) % ($max - $min) + $min;
|
|
}
|
|
$crypto->setKey($key);
|
|
$crypto->setIV($iv);
|
|
$crypto->enableContinuousBuffer();
|
|
}
|
|
|
|
extract(unpack('Nrandom', $crypto->encrypt("\0\0\0\0")));
|
|
return abs($random) % ($max - $min) + $min;
|
|
}
|
|
?>
|