<?php /** * PrivateBin * * a zero-knowledge paste bin * * @link https://github.com/PrivateBin/PrivateBin * @copyright 2012 Sébastien SAUVAGE (sebsauvage.net) * @license https://www.opensource.org/licenses/zlib-license.php The zlib/libpng License * @version 1.3.1 */ namespace PrivateBin; use Exception; /** * Filter * * Provides data filtering functions. */ class Filter { /** * format a given time string into a human readable label (localized) * * accepts times in the format "[integer][time unit]" * * @access public * @static * @param string $time * @throws Exception * @return string */ public static function formatHumanReadableTime($time) { if (preg_match('/^(\d+) *(\w+)$/', $time, $matches) !== 1) { throw new Exception("Error parsing time format '$time'", 30); } switch ($matches[2]) { case 'sec': $unit = 'second'; break; case 'min': $unit = 'minute'; break; default: $unit = rtrim($matches[2], 's'); } return I18n::_(array('%d ' . $unit, '%d ' . $unit . 's'), (int) $matches[1]); } /** * format a given number of bytes in IEC 80000-13:2008 notation (localized) * * @access public * @static * @param int $size * @return string */ public static function formatHumanReadableSize($size) { $iec = array('B', 'KiB', 'MiB', 'GiB', 'TiB', 'PiB', 'EiB', 'ZiB', 'YiB'); $i = 0; while (($size / 1024) >= 1) { $size = $size / 1024; ++$i; } return number_format($size, ($i ? 2 : 0), '.', ' ') . ' ' . I18n::_($iec[$i]); } /** * fixed time string comparison operation to prevent timing attacks * https://crackstation.net/hashing-security.htm?=rd#slowequals * * @access public * @static * @param string $a * @param string $b * @return bool */ public static function slowEquals($a, $b) { $diff = strlen($a) ^ strlen($b); for ($i = 0; $i < strlen($a) && $i < strlen($b); ++$i) { $diff |= ord($a[$i]) ^ ord($b[$i]); } return $diff === 0; } }