Файл: framework/security/RandomGenerator.php
Строк: 139
<?php
/**
* Generates entropy values based on strongest available methods
* (mcrypt_create_iv(), openssl_random_pseudo_bytes(), /dev/urandom, COM.CAPICOM.Utilities.1, mt_rand()).
* Chosen method depends on operating system and PHP version.
*
* @package framework
* @subpackage security
* @author Ingo Schommer
*/
class RandomGenerator {
/**
* Note: Returned values are not guaranteed to be crypto-safe,
* depending on the used retrieval method.
*
* @return string Returns a random series of bytes
*/
public function generateEntropy() {
$isWin = preg_match('/WIN/', PHP_OS);
// TODO Fails with "Could not gather sufficient random data" on IIS, temporarily disabled on windows
if(!$isWin) {
if(function_exists('mcrypt_create_iv')) {
$e = mcrypt_create_iv(64, MCRYPT_DEV_URANDOM);
if($e !== false) return $e;
}
}
// Fall back to SSL methods - may slow down execution by a few ms
if (function_exists('openssl_random_pseudo_bytes')) {
$e = openssl_random_pseudo_bytes(64, $strong);
// Only return if strong algorithm was used
if($strong) return $e;
}
// Read from the unix random number generator
if(!$isWin && !ini_get('open_basedir') && is_readable('/dev/urandom') && ($h = fopen('/dev/urandom', 'rb'))) {
$e = fread($h, 64);
fclose($h);
return $e;
}
// Warning: Both methods below are considered weak
// try to read from the windows RNG
if($isWin && class_exists('COM')) {
try {
$comObj = new COM('CAPICOM.Utilities.1');
if(is_callable(array($comObj,'GetRandom'))) {
return base64_decode($comObj->GetRandom(64, 0));
}
} catch (Exception $ex) {
}
}
// Fallback to good old mt_rand()
return uniqid(mt_rand(), true);
}
/**
* Generates a random token that can be used for session IDs, CSRF tokens etc., based on
* hash algorithms.
*
* If you are using it as a password equivalent (e.g. autologin token) do NOT store it
* in the database as a plain text but encrypt it with Member::encryptWithUserSettings.
*
* @param String $algorithm Any identifier listed in hash_algos() (Default: whirlpool)
*
* @return String Returned length will depend on the used $algorithm
*/
public function randomToken($algorithm = 'whirlpool') {
return hash($algorithm, $this->generateEntropy());
}
/**
* @deprecated
*/
public function generateHash($algorithm = 'whirlpool') {
Deprecation::notice('4.0',
'RandomGenerator::generateHash is deprecated because of a confusing name that hints the output is secure, '.
'while in fact it is just a random string. Use RandomGenerator::randomToken instead.',
Deprecation::SCOPE_METHOD
);
return $this->randomToken($algorithm);
}
}