WordPress/wp-includes/random_compat/byte_safe_strings.php
Dion Hulse 4852cbf14b Use PHP7's random_int() CSPRNG functionality in wp_rand() with a fallback to the random_compat library for PHP 5.x.
`random_compat` offers a set of compatible functions for older versions of PHP, filling in the gap by using other PHP extensions when available.
We still include our existing `wp_rand()` functionality as a fallback for when no proper CSPRNG exists on the system.

Take Two, this was previously committed in [34922] but had an issue on PHP 5.2 which sarciszewski has now resolved.

Props sarciszewski
See #28633

Built from https://develop.svn.wordpress.org/trunk@34981


git-svn-id: http://core.svn.wordpress.org/trunk@34946 1a063a9b-81f0-0310-95a4-ce76da25c4cd
2015-10-09 04:28:24 +00:00

155 lines
5.5 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.
*/
if (!function_exists('RandomCompat_strlen')) {
if (defined('MB_OVERLOAD_STRING') && ini_get('mbstring.func_overload') & MB_OVERLOAD_STRING) {
/**
* strlen() implementation that isn't brittle to mbstring.func_overload
*
* This version uses mb_strlen() in '8bit' mode to treat strings as raw
* binary rather than UTF-8, ISO-8859-1, etc
*
* @param string $binary_string
*
* @throws TypeError
*
* @return int
*/
function RandomCompat_strlen($binary_string)
{
if (!is_string($binary_string)) {
throw new TypeError(
'RandomCompat_strlen() expects a string'
);
}
return mb_strlen($binary_string, '8bit');
}
} else {
/**
* strlen() implementation that isn't brittle to mbstring.func_overload
*
* This version just used the default strlen()
*
* @param string $binary_string
*
* @throws TypeError
*
* @return int
*/
function RandomCompat_strlen($binary_string)
{
if (!is_string($binary_string)) {
throw new TypeError(
'RandomCompat_strlen() expects a string'
);
}
return strlen($binary_string);
}
}
}
if (!function_exists('RandomCompat_substr')) {
if (defined('MB_OVERLOAD_STRING') && ini_get('mbstring.func_overload') & MB_OVERLOAD_STRING) {
/**
* substr() implementation that isn't brittle to mbstring.func_overload
*
* This version uses mb_substr() in '8bit' mode to treat strings as raw
* binary rather than UTF-8, ISO-8859-1, etc
*
* @param string $binary_string
* @param int $start
* @param int $length (optional)
*
* @throws TypeError
*
* @return string
*/
function RandomCompat_substr($binary_string, $start, $length = null)
{
if (!is_string($binary_string)) {
throw new TypeError(
'RandomCompat_substr(): First argument should be a string'
);
}
if (!is_int($start)) {
throw new TypeError(
'RandomCompat_substr(): Second argument should be an integer'
);
}
if ($length === null) {
/**
* mb_substr($str, 0, NULL, '8bit') returns an empty string on
* PHP 5.3, so we have to find the length ourselves.
*/
$length = RandomCompat_strlen($length) - $start;
} elseif (!is_int($length)) {
throw new TypeError(
'RandomCompat_substr(): Third argument should be an integer, or omitted'
);
}
return mb_substr($binary_string, $start, $length, '8bit');
}
} else {
/**
* substr() implementation that isn't brittle to mbstring.func_overload
*
* This version just uses the default substr()
*
* @param string $binary_string
* @param int $start
* @param int $length (optional)
*
* @throws TypeError
*
* @return string
*/
function RandomCompat_substr($binary_string, $start, $length = null)
{
if (!is_string($binary_string)) {
throw new TypeError(
'RandomCompat_substr(): First argument should be a string'
);
}
if (!is_int($start)) {
throw new TypeError(
'RandomCompat_substr(): Second argument should be an integer'
);
}
if ($length !== null) {
if (!is_int($length)) {
throw new TypeError(
'RandomCompat_substr(): Third argument should be an integer, or omitted'
);
}
return substr($binary_string, $start, $length);
}
return substr($binary_string, $start);
}
}
}