diff options
Diffstat (limited to 'engine')
| -rw-r--r-- | engine/classes/ElggCrypto.php | 134 | ||||
| -rw-r--r-- | engine/lib/actions.php | 27 | ||||
| -rw-r--r-- | engine/lib/admin.php | 2 | ||||
| -rw-r--r-- | engine/lib/upgrades/2013060900-1.8.15-site_secret-404fc165cf9e0ac9.php | 13 |
4 files changed, 174 insertions, 2 deletions
diff --git a/engine/classes/ElggCrypto.php b/engine/classes/ElggCrypto.php new file mode 100644 index 000000000..364af4542 --- /dev/null +++ b/engine/classes/ElggCrypto.php @@ -0,0 +1,134 @@ +<?php +/** + * ElggCrypto + * + * @package Elgg.Core + * @subpackage Crypto + * + * @access private + */ +class ElggCrypto { + + /** + * Character set for temp passwords (no risk of embedded profanity/glyphs that look similar) + */ + const CHARS_PASSWORD = 'bcdfghjklmnpqrstvwxyz2346789'; + + /** + * Returns a string of highly randomized bytes (over the full 8-bit range). + * + * This function is better than simply calling mt_rand() or any other built-in + * PHP function because it can return a long string of bytes (compared to < 4 + * bytes normally from mt_rand()) and uses the best available pseudo-random + * source. + * + * @param int $count The number of characters (bytes) to return in the string. + * @return string + * + * @copyright Copyright 2001 - 2012 by the original authors + * https://github.com/drupal/drupal/blob/7.x/COPYRIGHT.txt + * @license https://github.com/drupal/drupal/blob/7.x/LICENSE.txt GPL 2 + * + * @see https://github.com/drupal/drupal/blob/7.x/includes/bootstrap.inc#L1942 + */ + public static function getRandomBytes($count) { + // $random_state does not use drupal_static as it stores random bytes. + static $random_state, $bytes, $php_compatible; + // Initialize on the first call. The contents of $_SERVER includes a mix of + // user-specific and system information that varies a little with each page. + if (!isset($random_state)) { + $random_state = print_r($_SERVER, true); + if (function_exists('getmypid')) { + // Further initialize with the somewhat random PHP process ID. + $random_state .= getmypid(); + } + $bytes = ''; + } + if (strlen($bytes) < $count) { + // PHP versions prior 5.3.4 experienced openssl_random_pseudo_bytes() + // locking on Windows and rendered it unusable. + if (!isset($php_compatible)) { + $php_compatible = version_compare(PHP_VERSION, '5.3.4', '>='); + } + // /dev/urandom is available on many *nix systems and is considered the + // best commonly available pseudo-random source. + if ($fh = @fopen('/dev/urandom', 'rb')) { + // PHP only performs buffered reads, so in reality it will always read + // at least 4096 bytes. Thus, it costs nothing extra to read and store + // that much so as to speed any additional invocations. + $bytes .= fread($fh, max(4096, $count)); + fclose($fh); + } elseif ($php_compatible && function_exists('openssl_random_pseudo_bytes')) { + // openssl_random_pseudo_bytes() will find entropy in a system-dependent + // way. + $bytes .= openssl_random_pseudo_bytes($count - strlen($bytes)); + } + // If /dev/urandom is not available or returns no bytes, this loop will + // generate a good set of pseudo-random bytes on any system. + // Note that it may be important that our $random_state is passed + // through hash() prior to being rolled into $output, that the two hash() + // invocations are different, and that the extra input into the first one - + // the microtime() - is prepended rather than appended. This is to avoid + // directly leaking $random_state via the $output stream, which could + // allow for trivial prediction of further "random" numbers. + while (strlen($bytes) < $count) { + $random_state = hash('sha256', microtime() . mt_rand() . $random_state); + $bytes .= hash('sha256', mt_rand() . $random_state, true); + } + } + $output = substr($bytes, 0, $count); + $bytes = substr($bytes, $count); + return $output; + } + + /** + * Generate a random string of specified length. + * + * Uses supplied character list for generating the new string. + * If no character list provided - uses Base64 URL character set. + * + * @param int $length Desired length of the string + * @param string|null $chars Characters to be chosen from randomly. If not given, the Base64 URL + * charset will be used. + * + * @return string The random string + * + * @throws InvalidArgumentException + * + * @copyright Copyright (c) 2005-2013 Zend Technologies USA Inc. (http://www.zend.com) + * @license http://framework.zend.com/license/new-bsd New BSD License + * + * @see https://github.com/zendframework/zf2/blob/master/library/Zend/Math/Rand.php#L179 + */ + public static function getRandomString($length, $chars = null) + { + if ($length < 1) { + throw new InvalidArgumentException('Length should be >= 1'); + } + + if (empty($chars)) { + $numBytes = ceil($length * 0.75); + $bytes = self::getRandomBytes($numBytes); + $string = substr(rtrim(base64_encode($bytes), '='), 0, $length); + + // Base64 URL + return strtr($string, '+/', '-_'); + } + + $listLen = strlen($chars); + + if ($listLen == 1) { + return str_repeat($chars, $length); + } + + $bytes = self::getRandomBytes($length); + $pos = 0; + $result = ''; + for ($i = 0; $i < $length; $i++) { + $pos = ($pos + ord($bytes[$i])) % $listLen; + $result .= $chars[$pos]; + } + + return $result; + } +} diff --git a/engine/lib/actions.php b/engine/lib/actions.php index 56936f582..8047914ac 100644 --- a/engine/lib/actions.php +++ b/engine/lib/actions.php @@ -364,16 +364,19 @@ function generate_action_token($timestamp) { } /** - * Initialise the site secret hash. + * Initialise the site secret (32 bytes: "z" to indicate format + 186-bit key in Base64 URL). * * Used during installation and saves as a datalist. * + * Note: Old secrets were hex encoded. + * * @return mixed The site secret hash or false * @access private * @todo Move to better file. */ function init_site_secret() { - $secret = md5(rand() . microtime()); + $secret = 'z' . ElggCrypto::getRandomString(31); + if (datalist_set('__site_secret__', $secret)) { return $secret; } @@ -400,6 +403,26 @@ function get_site_secret() { } /** + * Get the strength of the site secret + * + * @return string "strong", "moderate", or "weak" + * @access private + */ +function _elgg_get_site_secret_strength() { + $secret = get_site_secret(); + if ($secret[0] !== 'z') { + $rand_max = getrandmax(); + if ($rand_max < pow(2, 16)) { + return 'weak'; + } + if ($rand_max < pow(2, 32)) { + return 'moderate'; + } + } + return 'strong'; +} + +/** * Check if an action is registered and its script exists. * * @param string $action Action name diff --git a/engine/lib/admin.php b/engine/lib/admin.php index 7f82108c0..f36f29668 100644 --- a/engine/lib/admin.php +++ b/engine/lib/admin.php @@ -236,6 +236,7 @@ function admin_init() { elgg_register_action('admin/site/update_advanced', '', 'admin'); elgg_register_action('admin/site/flush_cache', '', 'admin'); elgg_register_action('admin/site/unlock_upgrade', '', 'admin'); + elgg_register_action('admin/site/regenerate_secret', '', 'admin'); elgg_register_action('admin/menu/save', '', 'admin'); @@ -291,6 +292,7 @@ function admin_init() { elgg_register_admin_menu_item('configure', 'settings', null, 100); elgg_register_admin_menu_item('configure', 'basic', 'settings', 10); elgg_register_admin_menu_item('configure', 'advanced', 'settings', 20); + elgg_register_admin_menu_item('configure', 'advanced/site_secret', 'settings', 25); elgg_register_admin_menu_item('configure', 'menu_items', 'appearance', 30); elgg_register_admin_menu_item('configure', 'profile_fields', 'appearance', 40); // default widgets is added via an event handler elgg_default_widgets_init() in widgets.php diff --git a/engine/lib/upgrades/2013060900-1.8.15-site_secret-404fc165cf9e0ac9.php b/engine/lib/upgrades/2013060900-1.8.15-site_secret-404fc165cf9e0ac9.php new file mode 100644 index 000000000..b5b614762 --- /dev/null +++ b/engine/lib/upgrades/2013060900-1.8.15-site_secret-404fc165cf9e0ac9.php @@ -0,0 +1,13 @@ +<?php +/** + * Elgg 1.8.15 upgrade 2013060900 + * site_secret + * + * Description + */ + +$strength = _elgg_get_site_secret_strength(); + +if ($strength !== 'strong') { + elgg_add_admin_notice('weak_site_key', elgg_echo("upgrade:site_secret_warning:$strength")); +} |