--- /dev/null
+<?php
+
+/**
+ * Random Number Generator
+ *
+ * The idea behind this function is that it can be easily replaced with your own crypt_random_string()
+ * function. eg. maybe you have a better source of entropy for creating the initial states or whatever.
+ *
+ * PHP versions 4 and 5
+ *
+ * Here's a short example of how to use this library:
+ * <code>
+ * <?php
+ * include 'Crypt/Random.php';
+ *
+ * echo bin2hex(crypt_random_string(8));
+ * ?>
+ * </code>
+ *
+ * LICENSE: 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.
+ *
+ * @category Crypt
+ * @package Crypt_Random
+ * @author Jim Wigginton <terrafrost@php.net>
+ * @copyright 2007 Jim Wigginton
+ * @license http://www.opensource.org/licenses/mit-license.html MIT License
+ * @link http://phpseclib.sourceforge.net
+ */
+
+// laravel is a PHP framework that utilizes phpseclib. laravel workbenches may, independently,
+// have phpseclib as a requirement as well. if you're developing such a program you may encounter
+// a "Cannot redeclare crypt_random_string()" error.
+if (!function_exists('crypt_random_string')) {
+ /**
+ * "Is Windows" test
+ *
+ * @access private
+ */
+ define('CRYPT_RANDOM_IS_WINDOWS', strtoupper(substr(PHP_OS, 0, 3)) === 'WIN');
+
+ /**
+ * Generate a random string.
+ *
+ * Although microoptimizations are generally discouraged as they impair readability this function is ripe with
+ * microoptimizations because this function has the potential of being called a huge number of times.
+ * eg. for RSA key generation.
+ *
+ * @param Integer $length
+ * @return String
+ * @access public
+ */
+ function crypt_random_string($length)
+ {
+ if (CRYPT_RANDOM_IS_WINDOWS) {
+ // method 1. prior to PHP 5.3 this would call rand() on windows hence the function_exists('class_alias') call.
+ // ie. class_alias is a function that was introduced in PHP 5.3
+ if (function_exists('mcrypt_create_iv') && function_exists('class_alias')) {
+ return mcrypt_create_iv($length);
+ }
+ // method 2. openssl_random_pseudo_bytes was introduced in PHP 5.3.0 but prior to PHP 5.3.4 there was,
+ // to quote <http://php.net/ChangeLog-5.php#5.3.4>, "possible blocking behavior". as of 5.3.4
+ // openssl_random_pseudo_bytes and mcrypt_create_iv do the exact same thing on Windows. ie. they both
+ // call php_win32_get_random_bytes():
+ //
+ // https://github.com/php/php-src/blob/7014a0eb6d1611151a286c0ff4f2238f92c120d6/ext/openssl/openssl.c#L5008
+ // https://github.com/php/php-src/blob/7014a0eb6d1611151a286c0ff4f2238f92c120d6/ext/mcrypt/mcrypt.c#L1392
+ //
+ // php_win32_get_random_bytes() is defined thusly:
+ //
+ // https://github.com/php/php-src/blob/7014a0eb6d1611151a286c0ff4f2238f92c120d6/win32/winutil.c#L80
+ //
+ // we're calling it, all the same, in the off chance that the mcrypt extension is not available
+ if (function_exists('openssl_random_pseudo_bytes') && version_compare(PHP_VERSION, '5.3.4', '>=')) {
+ return openssl_random_pseudo_bytes($length);
+ }
+ } else {
+ // method 1. the fastest
+ if (function_exists('openssl_random_pseudo_bytes')) {
+ return openssl_random_pseudo_bytes($length);
+ }
+ // method 2
+ static $fp = true;
+ if ($fp === true) {
+ // warning's will be output unles the error suppression operator is used. errors such as
+ // "open_basedir restriction in effect", "Permission denied", "No such file or directory", etc.
+ $fp = @fopen('/dev/urandom', 'rb');
+ }
+ if ($fp !== true && $fp !== false) { // surprisingly faster than !is_bool() or is_resource()
+ return fread($fp, $length);
+ }
+ // method 3. pretty much does the same thing as method 2 per the following url:
+ // https://github.com/php/php-src/blob/7014a0eb6d1611151a286c0ff4f2238f92c120d6/ext/mcrypt/mcrypt.c#L1391
+ // surprisingly slower than method 2. maybe that's because mcrypt_create_iv does a bunch of error checking that we're
+ // not doing. regardless, this'll only be called if this PHP script couldn't open /dev/urandom due to open_basedir
+ // restrictions or some such
+ if (function_exists('mcrypt_create_iv')) {
+ return mcrypt_create_iv($length, MCRYPT_DEV_URANDOM);
+ }
+ }
+ // at this point we have no choice but to use a pure-PHP CSPRNG
+
+ // cascade entropy across multiple PHP instances by fixing the session and collecting all
+ // environmental variables, including the previous session data and the current session
+ // data.
+ //
+ // mt_rand seeds itself by looking at the PID and the time, both of which are (relatively)
+ // easy to guess at. linux uses mouse clicks, keyboard timings, etc, as entropy sources, but
+ // PHP isn't low level to be able to use those as sources and on a web server there's not likely
+ // going to be a ton of keyboard or mouse action. web servers do have one thing that we can use
+ // however, a ton of people visiting the website. obviously you don't want to base your seeding
+ // soley on parameters a potential attacker sends but (1) not everything in $_SERVER is controlled
+ // by the user and (2) this isn't just looking at the data sent by the current user - it's based
+ // on the data sent by all users. one user requests the page and a hash of their info is saved.
+ // another user visits the page and the serialization of their data is utilized along with the
+ // server envirnment stuff and a hash of the previous http request data (which itself utilizes
+ // a hash of the session data before that). certainly an attacker should be assumed to have
+ // full control over his own http requests. he, however, is not going to have control over
+ // everyone's http requests.
+ static $crypto = false, $v;
+ if ($crypto === false) {
+ // save old session data
+ $old_session_id = session_id();
+ $old_use_cookies = ini_get('session.use_cookies');
+ $old_session_cache_limiter = session_cache_limiter();
+ $_OLD_SESSION = isset($_SESSION) ? $_SESSION : false;
+ if ($old_session_id != '') {
+ session_write_close();
+ }
+
+ session_id(1);
+ ini_set('session.use_cookies', 0);
+ session_cache_limiter('');
+ session_start();
+
+ $v = $seed = $_SESSION['seed'] = pack('H*', sha1(
+ serialize($_SERVER) .
+ serialize($_POST) .
+ serialize($_GET) .
+ serialize($_COOKIE) .
+ serialize($GLOBALS) .
+ serialize($_SESSION) .
+ serialize($_OLD_SESSION)
+ ));
+ if (!isset($_SESSION['count'])) {
+ $_SESSION['count'] = 0;
+ }
+ $_SESSION['count']++;
+
+ session_write_close();
+
+ // restore old session data
+ if ($old_session_id != '') {
+ session_id($old_session_id);
+ session_start();
+ ini_set('session.use_cookies', $old_use_cookies);
+ session_cache_limiter($old_session_cache_limiter);
+ } else {
+ if ($_OLD_SESSION !== false) {
+ $_SESSION = $_OLD_SESSION;
+ unset($_OLD_SESSION);
+ } else {
+ unset($_SESSION);
+ }
+ }
+
+ // in SSH2 a shared secret and an exchange hash are generated through the key exchange process.
+ // the IV client to server is the hash of that "nonce" with the letter A and for the encryption key it's the letter C.
+ // if the hash doesn't produce enough a key or an IV that's long enough concat successive hashes of the
+ // original hash and the current hash. we'll be emulating that. for more info see the following URL:
+ //
+ // http://tools.ietf.org/html/rfc4253#section-7.2
+ //
+ // see the is_string($crypto) part for an example of how to expand the keys
+ $key = pack('H*', sha1($seed . 'A'));
+ $iv = pack('H*', sha1($seed . 'C'));
+
+ // ciphers are used as per the nist.gov link below. also, see this link:
+ //
+ // http://en.wikipedia.org/wiki/Cryptographically_secure_pseudorandom_number_generator#Designs_based_on_cryptographic_primitives
+ switch (true) {
+ case phpseclib_resolve_include_path('Crypt/AES.php'):
+ if (!class_exists('Crypt_AES')) {
+ include_once 'AES.php';
+ }
+ $crypto = new Crypt_AES(CRYPT_AES_MODE_CTR);
+ break;
+ case phpseclib_resolve_include_path('Crypt/Twofish.php'):
+ if (!class_exists('Crypt_Twofish')) {
+ include_once 'Twofish.php';
+ }
+ $crypto = new Crypt_Twofish(CRYPT_TWOFISH_MODE_CTR);
+ break;
+ case phpseclib_resolve_include_path('Crypt/Blowfish.php'):
+ if (!class_exists('Crypt_Blowfish')) {
+ include_once 'Blowfish.php';
+ }
+ $crypto = new Crypt_Blowfish(CRYPT_BLOWFISH_MODE_CTR);
+ break;
+ case phpseclib_resolve_include_path('Crypt/TripleDES.php'):
+ if (!class_exists('Crypt_TripleDES')) {
+ include_once 'TripleDES.php';
+ }
+ $crypto = new Crypt_TripleDES(CRYPT_DES_MODE_CTR);
+ break;
+ case phpseclib_resolve_include_path('Crypt/DES.php'):
+ if (!class_exists('Crypt_DES')) {
+ include_once 'DES.php';
+ }
+ $crypto = new Crypt_DES(CRYPT_DES_MODE_CTR);
+ break;
+ case phpseclib_resolve_include_path('Crypt/RC4.php'):
+ if (!class_exists('Crypt_RC4')) {
+ include_once 'RC4.php';
+ }
+ $crypto = new Crypt_RC4();
+ break;
+ default:
+ user_error('crypt_random_string requires at least one symmetric cipher be loaded');
+ return false;
+ }
+
+ $crypto->setKey($key);
+ $crypto->setIV($iv);
+ $crypto->enableContinuousBuffer();
+ }
+
+ //return $crypto->encrypt(str_repeat("\0", $length));
+
+ // the following is based off of ANSI X9.31:
+ //
+ // http://csrc.nist.gov/groups/STM/cavp/documents/rng/931rngext.pdf
+ //
+ // OpenSSL uses that same standard for it's random numbers:
+ //
+ // http://www.opensource.apple.com/source/OpenSSL/OpenSSL-38/openssl/fips-1.0/rand/fips_rand.c
+ // (do a search for "ANS X9.31 A.2.4")
+ $result = '';
+ while (strlen($result) < $length) {
+ $i = $crypto->encrypt(microtime()); // strlen(microtime()) == 21
+ $r = $crypto->encrypt($i ^ $v); // strlen($v) == 20
+ $v = $crypto->encrypt($r ^ $i); // strlen($r) == 20
+ $result.= $r;
+ }
+ return substr($result, 0, $length);
+ }
+}
+
+if (!function_exists('phpseclib_resolve_include_path')) {
+ /**
+ * Resolve filename against the include path.
+ *
+ * Wrapper around stream_resolve_include_path() (which was introduced in
+ * PHP 5.3.2) with fallback implementation for earlier PHP versions.
+ *
+ * @param string $filename
+ * @return mixed Filename (string) on success, false otherwise.
+ * @access public
+ */
+ function phpseclib_resolve_include_path($filename)
+ {
+ if (function_exists('stream_resolve_include_path')) {
+ return stream_resolve_include_path($filename);
+ }
+
+ // handle non-relative paths
+ if (file_exists($filename)) {
+ return realpath($filename);
+ }
+
+ $paths = PATH_SEPARATOR == ':' ?
+ preg_split('#(?<!phar):#', get_include_path()) :
+ explode(PATH_SEPARATOR, get_include_path());
+ foreach ($paths as $prefix) {
+ // path's specified in include_path don't always end in /
+ $ds = substr($prefix, -1) == DIRECTORY_SEPARATOR ? '' : DIRECTORY_SEPARATOR;
+ $file = $prefix . $ds . $filename;
+ if (file_exists($file)) {
+ return realpath($file);
+ }
+ }
+
+ return false;
+ }
+}
projects / friendica-addons.git / blobdiff