3 * Random_* Compatibility Library
4 * for using the new PHP 7 random_* API in PHP 5 projects
6 * The MIT License (MIT)
8 * Copyright (c) 2015 - 2017 Paragon Initiative Enterprises
10 * Permission is hereby granted, free of charge, to any person obtaining a copy
11 * of this software and associated documentation files (the "Software"), to deal
12 * in the Software without restriction, including without limitation the rights
13 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
14 * copies of the Software, and to permit persons to whom the Software is
15 * furnished to do so, subject to the following conditions:
17 * The above copyright notice and this permission notice shall be included in
18 * all copies or substantial portions of the Software.
20 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
21 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
22 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
23 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
24 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
25 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
29 if (!is_callable('random_bytes')) {
31 * Windows with PHP < 5.3.0 will not have the function
32 * openssl_random_pseudo_bytes() available, so let's use
33 * CAPICOM to work around this deficiency.
41 function random_bytes($bytes)
44 $bytes = RandomCompat_intval($bytes);
45 } catch (TypeError $ex) {
47 'random_bytes(): $bytes must be an integer'
53 'Length must be greater than 0'
58 if (!class_exists('COM')) {
63 $util = new COM('CAPICOM.Utilities.1');
67 * Let's not let it loop forever. If we run N times and fail to
68 * get N bytes of random data, then CAPICOM has failed us.
71 $buf .= base64_decode($util->GetRandom($bytes, 0));
72 if (RandomCompat_strlen($buf) >= $bytes) {
74 * Return our random entropy buffer here:
76 return RandomCompat_substr($buf, 0, $bytes);
79 } while ($execCount < $bytes);
82 * If we reach here, PHP has failed us.
85 'Could not gather sufficient random data'