Rev 83 | Go to most recent revision | Details | Compare with Previous | Last modification | View Log | RSS feed
| Rev | Author | Line No. | Line |
|---|---|---|---|
| 2 | daniel-mar | 1 | <?php |
| 2 | |||
| 3 | /* |
||
| 4 | * OIDplus 2.0 |
||
| 5 | * Copyright 2019 Daniel Marschall, ViaThinkSoft |
||
| 6 | * |
||
| 7 | * Licensed under the Apache License, Version 2.0 (the "License"); |
||
| 8 | * you may not use this file except in compliance with the License. |
||
| 9 | * You may obtain a copy of the License at |
||
| 10 | * |
||
| 11 | * http://www.apache.org/licenses/LICENSE-2.0 |
||
| 12 | * |
||
| 13 | * Unless required by applicable law or agreed to in writing, software |
||
| 14 | * distributed under the License is distributed on an "AS IS" BASIS, |
||
| 15 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
||
| 16 | * See the License for the specific language governing permissions and |
||
| 17 | * limitations under the License. |
||
| 18 | */ |
||
| 19 | |||
| 85 | daniel-mar | 20 | define('SESSION_LIFETIME', 10*60); // TODO: Configure |
| 21 | |||
| 2 | daniel-mar | 22 | class OIDplusSessionHandler { |
| 23 | |||
| 24 | protected $secret = ''; |
||
| 25 | |||
| 26 | function __construct($secret) { |
||
| 27 | // **PREVENTING SESSION HIJACKING** |
||
| 28 | // Prevents javascript XSS attacks aimed to steal the session ID |
||
| 29 | ini_set('session.cookie_httponly', 1); |
||
| 30 | |||
| 31 | // **PREVENTING SESSION FIXATION** |
||
| 32 | // Session ID cannot be passed through URLs |
||
| 33 | ini_set('session.use_only_cookies', 1); |
||
| 34 | |||
| 85 | daniel-mar | 35 | ini_set('session.use_trans_sid', 0); |
| 36 | |||
| 2 | daniel-mar | 37 | // Uses a secure connection (HTTPS) if possible |
| 42 | daniel-mar | 38 | ini_set('session.cookie_secure', OIDPLUS_SSL_AVAILABLE); |
| 2 | daniel-mar | 39 | |
| 83 | daniel-mar | 40 | $path = OIDplus::system_url(true); |
| 41 | if (!empty($path)) { |
||
| 42 | ini_set('session.cookie_path', $path); |
||
| 2 | daniel-mar | 43 | } |
| 44 | |||
| 45 | ini_set('session.cookie_samesite', 'Lax'); |
||
| 46 | |||
| 85 | daniel-mar | 47 | ini_set('session.use_strict_mode', 1); |
| 2 | daniel-mar | 48 | |
| 85 | daniel-mar | 49 | ini_set('session.gc_maxlifetime', SESSION_LIFETIME); |
| 50 | |||
| 2 | daniel-mar | 51 | $this->secret = $secret; |
| 85 | daniel-mar | 52 | |
| 53 | session_name('OIDPLUS_SESHDLR'); |
||
| 2 | daniel-mar | 54 | } |
| 55 | |||
| 56 | function __destruct() { |
||
| 57 | session_write_close(); |
||
| 58 | } |
||
| 59 | |||
| 60 | public function setValue($name, $value) { |
||
| 85 | daniel-mar | 61 | @session_start(); |
| 62 | setcookie(session_name(),session_id(),time()+SESSION_LIFETIME, ini_get('session.cookie_path')); |
||
| 63 | |||
| 2 | daniel-mar | 64 | $_SESSION[$name] = self::encrypt($value, $this->secret); |
| 65 | } |
||
| 66 | |||
| 67 | public function getValue($name) { |
||
| 85 | daniel-mar | 68 | if (!isset($_COOKIE[session_name()])) return null; // GDPR: Only start a session when we really need one |
| 69 | |||
| 70 | @session_start(); |
||
| 71 | setcookie(session_name(),session_id(),time()+SESSION_LIFETIME, ini_get('session.cookie_path')); |
||
| 72 | |||
| 2 | daniel-mar | 73 | if (!isset($_SESSION[$name])) return null; |
| 74 | return self::decrypt($_SESSION[$name], $this->secret); |
||
| 75 | } |
||
| 76 | |||
| 85 | daniel-mar | 77 | public function destroySession() { |
| 78 | if (!isset($_COOKIE[session_name()])) return; |
||
| 79 | |||
| 80 | @session_start(); |
||
| 81 | setcookie(session_name(),session_id(),time()+SESSION_LIFETIME, ini_get('session.cookie_path')); |
||
| 82 | |||
| 83 | $_SESSION = array(); |
||
| 84 | session_destroy(); |
||
| 85 | session_write_close(); |
||
| 86 | setcookie(session_name(), "", time()-3600, ini_get('session.cookie_path')); // remove cookie, so GDPR people are happy |
||
| 87 | } |
||
| 88 | |||
| 83 | daniel-mar | 89 | public function exists($name) { |
| 90 | return isset($_SESSION[$name]); |
||
| 91 | } |
||
| 92 | |||
| 2 | daniel-mar | 93 | protected static function encrypt($data, $key) { |
| 6 | daniel-mar | 94 | $iv = random_bytes(16); // AES block size in CBC mode |
| 95 | // Encryption |
||
| 96 | $ciphertext = openssl_encrypt( |
||
| 97 | $data, |
||
| 98 | 'AES-256-CBC', |
||
| 99 | mb_substr($key, 0, 32, '8bit'), |
||
| 100 | OPENSSL_RAW_DATA, |
||
| 101 | $iv |
||
| 102 | ); |
||
| 103 | // Authentication |
||
| 104 | $hmac = hash_hmac( |
||
| 105 | 'SHA256', |
||
| 106 | $iv . $ciphertext, |
||
| 107 | mb_substr($key, 32, null, '8bit'), |
||
| 108 | true |
||
| 109 | ); |
||
| 110 | return $hmac . $iv . $ciphertext; |
||
| 111 | } |
||
| 2 | daniel-mar | 112 | |
| 6 | daniel-mar | 113 | protected static function decrypt($data, $key) { |
| 114 | $hmac = mb_substr($data, 0, 32, '8bit'); |
||
| 115 | $iv = mb_substr($data, 32, 16, '8bit'); |
||
| 116 | $ciphertext = mb_substr($data, 48, null, '8bit'); |
||
| 117 | // Authentication |
||
| 118 | $hmacNew = hash_hmac( |
||
| 119 | 'SHA256', |
||
| 120 | $iv . $ciphertext, |
||
| 121 | mb_substr($key, 32, null, '8bit'), |
||
| 122 | true |
||
| 123 | ); |
||
| 124 | if (!hash_equals($hmac, $hmacNew)) { |
||
| 125 | throw new Exception('Authentication failed'); |
||
| 126 | } |
||
| 127 | // Decryption |
||
| 128 | return openssl_decrypt( |
||
| 129 | $ciphertext, |
||
| 130 | 'AES-256-CBC', |
||
| 131 | mb_substr($key, 0, 32, '8bit'), |
||
| 132 | OPENSSL_RAW_DATA, |
||
| 133 | $iv |
||
| 134 | ); |
||
| 135 | } |
||
| 2 | daniel-mar | 136 | } |