diff options
author | Evan Prodromou <evan@prodromou.name> | 2008-08-22 09:17:14 -0400 |
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committer | Evan Prodromou <evan@prodromou.name> | 2008-08-22 09:17:14 -0400 |
commit | 14c9366aac697e87499c5748b36fa7bf5e6cd320 (patch) | |
tree | 75cfb4355bb5200e3c505f49532b0d934261a8e9 /extlib/Auth/OpenID/CryptUtil.php | |
parent | dfdc8b777345875fb1d367ce3b9c91b372cd4dc3 (diff) |
include external libs in a subdir to make install easier
darcs-hash:20080822131714-84dde-6978424ded2ed1041a65142a25560654ac717fcd.gz
Diffstat (limited to 'extlib/Auth/OpenID/CryptUtil.php')
-rw-r--r-- | extlib/Auth/OpenID/CryptUtil.php | 109 |
1 files changed, 109 insertions, 0 deletions
diff --git a/extlib/Auth/OpenID/CryptUtil.php b/extlib/Auth/OpenID/CryptUtil.php new file mode 100644 index 000000000..aacc3cd39 --- /dev/null +++ b/extlib/Auth/OpenID/CryptUtil.php @@ -0,0 +1,109 @@ +<?php + +/** + * CryptUtil: A suite of wrapper utility functions for the OpenID + * library. + * + * PHP versions 4 and 5 + * + * LICENSE: See the COPYING file included in this distribution. + * + * @access private + * @package OpenID + * @author JanRain, Inc. <openid@janrain.com> + * @copyright 2005-2008 Janrain, Inc. + * @license http://www.apache.org/licenses/LICENSE-2.0 Apache + */ + +if (!defined('Auth_OpenID_RAND_SOURCE')) { + /** + * The filename for a source of random bytes. Define this yourself + * if you have a different source of randomness. + */ + define('Auth_OpenID_RAND_SOURCE', '/dev/urandom'); +} + +class Auth_OpenID_CryptUtil { + /** + * Get the specified number of random bytes. + * + * Attempts to use a cryptographically secure (not predictable) + * source of randomness if available. If there is no high-entropy + * randomness source available, it will fail. As a last resort, + * for non-critical systems, define + * <code>Auth_OpenID_RAND_SOURCE</code> as <code>null</code>, and + * the code will fall back on a pseudo-random number generator. + * + * @param int $num_bytes The length of the return value + * @return string $bytes random bytes + */ + function getBytes($num_bytes) + { + static $f = null; + $bytes = ''; + if ($f === null) { + if (Auth_OpenID_RAND_SOURCE === null) { + $f = false; + } else { + $f = @fopen(Auth_OpenID_RAND_SOURCE, "r"); + if ($f === false) { + $msg = 'Define Auth_OpenID_RAND_SOURCE as null to ' . + ' continue with an insecure random number generator.'; + trigger_error($msg, E_USER_ERROR); + } + } + } + if ($f === false) { + // pseudorandom used + $bytes = ''; + for ($i = 0; $i < $num_bytes; $i += 4) { + $bytes .= pack('L', mt_rand()); + } + $bytes = substr($bytes, 0, $num_bytes); + } else { + $bytes = fread($f, $num_bytes); + } + return $bytes; + } + + /** + * Produce a string of length random bytes, chosen from chrs. If + * $chrs is null, the resulting string may contain any characters. + * + * @param integer $length The length of the resulting + * randomly-generated string + * @param string $chrs A string of characters from which to choose + * to build the new string + * @return string $result A string of randomly-chosen characters + * from $chrs + */ + function randomString($length, $population = null) + { + if ($population === null) { + return Auth_OpenID_CryptUtil::getBytes($length); + } + + $popsize = strlen($population); + + if ($popsize > 256) { + $msg = 'More than 256 characters supplied to ' . __FUNCTION__; + trigger_error($msg, E_USER_ERROR); + } + + $duplicate = 256 % $popsize; + + $str = ""; + for ($i = 0; $i < $length; $i++) { + do { + $n = ord(Auth_OpenID_CryptUtil::getBytes(1)); + } while ($n < $duplicate); + + $n %= $popsize; + $str .= $population[$n]; + } + + return $str; + } +} + +?>
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