use Crypt::CBC;
use warnings;
use strict;
use MIME::Base64;

my $cipher = Crypt::CBC->new( {
  'literal_key' => 1,
  'key' => "a" x 32,
   'keysize'=>32,
                                    'cipher'=> 'Rijndael',
                                    'iv' => "\x00" x 16,
                                    'padding' => 'null',
                                    'prepend_iv' => 0
                                    });
my $cc = 'hello world';
my $encrypted = $cipher->encrypt($cc);
my $decrypted = $cipher->decrypt($encrypted);

print "encrypted : ".encode_base64($encrypted); # its: xY1F1cVS5p9/GNujSwXK2Q==
print "decrypted : ".$decrypted;

# trying to decrypt with php:
<?
$encrypted = base64_decode('xY1F1cVS5p9/GNujSwXK2Q==');
$key = 'aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa';
$iv = "";
for($i = 0; $i < 16; $i++)
  $iv .= chr(0);

$cipher = mcrypt_module_open(MCRYPT_RIJNDAEL_256,'','cbc','');

mcrypt_generic_init($cipher, $key, $iv);


$decrypted = mdecrypt_generic($cipher,$encrypted);
mcrypt_generic_deinit($cipher);

echo "decrypted : ".$decrypted; # should echo hello world... it doesnt.
?>