WordPress/wp-includes/random_compat/random_bytes_openssl.php

75 lines
2.4 KiB
PHP

<?php
/**
* Random_* Compatibility Library
* for using the new PHP 7 random_* API in PHP 5 projects
*
* The MIT License (MIT)
*
* Copyright (c) 2015 Paragon Initiative Enterprises
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
/**
* Since openssl_random_pseudo_bytes() uses openssl's
* RAND_pseudo_bytes() API, which has been marked as deprecated by the
* OpenSSL team, this is our last resort before failure.
*
* @ref https://www.openssl.org/docs/crypto/RAND_bytes.html
*
* @param int $bytes
*
* @throws Exception
*
* @return string
*/
function random_bytes($bytes)
{
if (!is_int($bytes)) {
throw new TypeError(
'Length must be an integer'
);
}
if ($bytes < 1) {
throw new Error(
'Length must be greater than 0'
);
}
$secure = true;
/**
* $secure is passed by reference. If it's set to false, fail. Note
* that this will only return false if this function fails to return
* any data.
*
* @ref https://github.com/paragonie/random_compat/issues/6#issuecomment-119564973
*/
$buf = openssl_random_pseudo_bytes($bytes, $secure);
if ($buf !== false && $secure) {
if (RandomCompat_strlen($buf) === $bytes) {
return $buf;
}
}
/**
* If we reach here, PHP has failed us.
*/
throw new Exception(
'PHP failed to generate random data.'
);
}