note 89419 rejected from function.mcrypt-decrypt by danbrown
| From: | danbrown@php.net | Date: | Sat, 07 Mar 2009 00:07:20 +0000 |
| Subject: | note 89419 rejected from function.mcrypt-decrypt by danbrown | ||
| References: | 1 | Groups: | php.notes |
| Request: | Send a blank email to php-notes+get-151576@lists.php.net to get a copy of this message | ||
Note Submitter: bbroerman at bbroerman dot net
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I am trying to use PHP decode to decrypt a message that was encrypted using the BSD implementation
of Rijndael in CBC mode with a zero filled IV, with the data encoded in base64. I implemented the
program using the BSD source for the crypt/rijndael library. The key was in hex, so I converted it
to binary with a call to pack('H*', $key) in the call to mcrypt_encrypt.
the php code is:
$decoded = base64_decode($cryptext);
$iv_size = mcrypt_get_iv_size(MCRYPT_RIJNDAEL_256, MCRYPT_MODE_CBC);
// split the input into the iv and the message.
$iv = substr($decoded,0,$iv_size);
$string = substr($decoded,$iv_size);
// decrypt it.
$decrypted = mcrypt_decrypt(MCRYPT_RIJNDAEL_256, pack('H*', $key), $string,
MCRYPT_MODE_CBC, $iv);
$plaintext = utf8_decode($decrypted);
When I decrypt a message/key produced by PHP it works fine. When I decrypt a message/key produced by
the C program, I get garbage back. I also tried doing different things with the iv block, as I
noticed that PHP needs 32 characters, and the C methods need 16.
Thanks in advance...