ÿØÿàJFIFÿþ ÿÛC       ÿÛC ÿÀÿÄÿÄ"#QrÿÄÿÄ&1!A"2qQaáÿÚ ?Øy,æ/3JæݹÈ߲؋5êXw²±ÉyˆR”¾I0ó2—PI¾IÌÚiMö¯–þrìN&"KgX:Šíµ•nTJnLK„…@!‰-ý ùúmë;ºgµŒ&ó±hw’¯Õ@”Ü— 9ñ-ë.²1<yà‚¹ïQÐU„ہ?.’¦èûbß±©Ö«Âw*VŒ) `$‰bØԟ’ëXÖ-ËTÜíGÚ3ð«g Ÿ§¯—Jx„–’U/ÂÅv_s(Hÿ@TñJÑãõçn­‚!ÈgfbÓc­:él[ðQe 9ÀPLbÃãCµm[5¿ç'ªjglå‡Ûí_§Úõl-;"PkÞÞÁQâ¼_Ñ^¢SŸx?"¸¦ùY騐ÒOÈ q’`~~ÚtËU¹CڒêV  I1Áß_ÿÙ * * For the full copyright and license information, please view the LICENSE * file that was distributed with this source code. */ namespace Symfony\Component\Security\Core\Util; /** * String utility functions. * * @author Fabien Potencier */ class StringUtils { /** * This class should not be instantiated */ private function __construct() {} /** * Compares two strings. * * This method implements a constant-time algorithm to compare strings. * * @param string $knownString The string of known length to compare against * @param string $userInput The string that the user can control * * @return Boolean true if the two strings are the same, false otherwise */ public static function equals($knownString, $userInput) { // Prevent issues if string length is 0 $knownString .= chr(0); $userInput .= chr(0); $knownLen = strlen($knownString); $userLen = strlen($userInput); // Set the result to the difference between the lengths $result = $knownLen - $userLen; // Note that we ALWAYS iterate over the user-supplied length // This is to prevent leaking length information for ($i = 0; $i < $userLen; $i++) { // Using % here is a trick to prevent notices // It's safe, since if the lengths are different // $result is already non-0 $result |= (ord($knownString[$i % $knownLen]) ^ ord($userInput[$i])); } // They are only identical strings if $result is exactly 0... return 0 === $result; } }