Шифрование по ключу

<?php
$phrase = 'secret message';
$key = 'KEY';
 
$encrypt = encrypt($key, $phrase);
$phrase = decrypt($key, $encrypt);
echo $encrypt, ' = ', $phrase;
 
function encrypt($key, $text) {
    $cipher = mcrypt_module_open(MCRYPT_BLOWFISH,'','cbc','');
    mcrypt_generic_init($cipher, $key, '12345678');
    $encrypted = mcrypt_generic($cipher,$text);
    mcrypt_generic_deinit($cipher);
    $encrypted = bin2hex($encrypted);
    return $encrypted;
}
 
function decrypt($key, $encrypted) {
    $encrypted = hex2bin($encrypted);
    $cipher = mcrypt_module_open(MCRYPT_BLOWFISH,'','cbc','');
    mcrypt_generic_init($cipher, $key, '12345678');
    $decrypted = mdecrypt_generic($cipher,$encrypted);
    mcrypt_generic_deinit($cipher);
    return $decrypted;
}