random_bytes_libsodium_legacy.php (2894B)
1 <?php 2 /** 3 * Random_* Compatibility Library 4 * for using the new PHP 7 random_* API in PHP 5 projects 5 * 6 * The MIT License (MIT) 7 * 8 * Copyright (c) 2015 - 2017 Paragon Initiative Enterprises 9 * 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: 16 * 17 * The above copyright notice and this permission notice shall be included in 18 * all copies or substantial portions of the Software. 19 * 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 26 * SOFTWARE. 27 */ 28 29 if (!is_callable('random_bytes')) { 30 /** 31 * If the libsodium PHP extension is loaded, we'll use it above any other 32 * solution. 33 * 34 * libsodium-php project: 35 * @ref https://github.com/jedisct1/libsodium-php 36 * 37 * @param int $bytes 38 * 39 * @throws Exception 40 * 41 * @return string 42 */ 43 function random_bytes($bytes) 44 { 45 try { 46 $bytes = RandomCompat_intval($bytes); 47 } catch (TypeError $ex) { 48 throw new TypeError( 49 'random_bytes(): $bytes must be an integer' 50 ); 51 } 52 53 if ($bytes < 1) { 54 throw new Error( 55 'Length must be greater than 0' 56 ); 57 } 58 59 /** 60 * @var string 61 */ 62 $buf = ''; 63 64 /** 65 * \Sodium\randombytes_buf() doesn't allow more than 2147483647 bytes to be 66 * generated in one invocation. 67 */ 68 if ($bytes > 2147483647) { 69 for ($i = 0; $i < $bytes; $i += 1073741824) { 70 $n = ($bytes - $i) > 1073741824 71 ? 1073741824 72 : $bytes - $i; 73 $buf .= Sodium::randombytes_buf((int) $n); 74 } 75 } else { 76 $buf .= Sodium::randombytes_buf((int) $bytes); 77 } 78 79 if (is_string($buf)) { 80 if (RandomCompat_strlen($buf) === $bytes) { 81 return $buf; 82 } 83 } 84 85 /** 86 * If we reach here, PHP has failed us. 87 */ 88 throw new Exception( 89 'Could not gather sufficient random data' 90 ); 91 } 92 }