From: zelnaga at gmail dot com Operating system: Windows XP PHP version: 5.3.1 PHP Bug Type: mcrypt related Bug description: mcrypt doesn't do OFB mode correctly
Description: ------------ Correct me if I'm wrong, but shouldn't an ECB decryption of an OFB encrypted string of null bytes produce a string whose first eight bytes (assuming that that's the block size) are equal to the IV? Certainly that's the impression I get from wikipedia.org's discussion of OFB. http://en.wikipedia.org/wiki/Block_cipher_modes_of_operation#Output_feedback_.28OFB.29 Reproduce code: --------------- <?php $td = mcrypt_module_open(MCRYPT_DES, '', MCRYPT_MODE_OFB, ''); mcrypt_generic_init($td, 'aaaaaaaa', 'bbbbbbbb'); $ciphertext = mcrypt_generic($td, "\0\0\0\0\0\0\0\0"); $td = mcrypt_module_open(MCRYPT_DES, '', MCRYPT_MODE_ECB, ''); mcrypt_generic_init($td, 'aaaaaaaa', "\0\0\0\0\0\0\0\0"); echo urlencode(mdecrypt_generic($td, $ciphertext)); ?> Expected result: ---------------- bbbbbbbb Actual result: -------------- 5%FBdq%C7Y7%13 -- Edit bug report at http://bugs.php.net/?id=51146&edit=1 -- Try a snapshot (PHP 5.2): http://bugs.php.net/fix.php?id=51146&r=trysnapshot52 Try a snapshot (PHP 5.3): http://bugs.php.net/fix.php?id=51146&r=trysnapshot53 Try a snapshot (PHP 6.0): http://bugs.php.net/fix.php?id=51146&r=trysnapshot60 Fixed in SVN: http://bugs.php.net/fix.php?id=51146&r=fixed Fixed in SVN and need be documented: http://bugs.php.net/fix.php?id=51146&r=needdocs Fixed in release: http://bugs.php.net/fix.php?id=51146&r=alreadyfixed Need backtrace: http://bugs.php.net/fix.php?id=51146&r=needtrace Need Reproduce Script: http://bugs.php.net/fix.php?id=51146&r=needscript Try newer version: http://bugs.php.net/fix.php?id=51146&r=oldversion Not developer issue: http://bugs.php.net/fix.php?id=51146&r=support Expected behavior: http://bugs.php.net/fix.php?id=51146&r=notwrong Not enough info: http://bugs.php.net/fix.php?id=51146&r=notenoughinfo Submitted twice: http://bugs.php.net/fix.php?id=51146&r=submittedtwice register_globals: http://bugs.php.net/fix.php?id=51146&r=globals PHP 4 support discontinued: http://bugs.php.net/fix.php?id=51146&r=php4 Daylight Savings: http://bugs.php.net/fix.php?id=51146&r=dst IIS Stability: http://bugs.php.net/fix.php?id=51146&r=isapi Install GNU Sed: http://bugs.php.net/fix.php?id=51146&r=gnused Floating point limitations: http://bugs.php.net/fix.php?id=51146&r=float No Zend Extensions: http://bugs.php.net/fix.php?id=51146&r=nozend MySQL Configuration Error: http://bugs.php.net/fix.php?id=51146&r=mysqlcfg
