/**
* Setup the \phpseclib\Crypt\Base::ENGINE_MCRYPT $engine
*
* @see \phpseclib\Crypt\Base::_setupMcrypt()
* @access private
*/
function _setupMcrypt()
{
if (!isset($this->key)) {
$this->setKey('');
}
parent::_setupMcrypt();
}
/**
* Sets the key length.
*
* Valid key lengths are 128, 192 or 256 bits
*
* @access public
* @param int $length
*/
function setKeyLength($length)
{
switch (true) {
case $length <= 128:
$this->key_length = 16;
break;
case $length <= 192:
$this->key_length = 24;
break;
default:
$this->key_length = 32;
}
parent::setKeyLength($length);
}
/**
* Decrypts a message.
*
* $this->decrypt($this->encrypt($plaintext)) == $this->encrypt($this->encrypt($plaintext)).
* At least if the continuous buffer is disabled.
*
* @see \phpseclib\Crypt\Base::encrypt()
* @see self::_crypt()
* @access public
* @param string $ciphertext
* @return string $plaintext
*/
function decrypt($ciphertext)
{
if ($this->engine != Base::ENGINE_INTERNAL) {
return parent::decrypt($ciphertext);
}
return $this->_crypt($ciphertext, self::DECRYPT);
}
/**
* Test for engine validity
*
* This is mainly just a wrapper to set things up for \phpseclib\Crypt\Base::isValidEngine()
*
* @see \phpseclib\Crypt\Base::isValidEngine()
* @param int $engine
* @access public
* @return bool
*/
function isValidEngine($engine)
{
if ($engine == self::ENGINE_OPENSSL) {
if ($this->key_length != 16) {
return false;
}
$this->cipher_name_openssl_ecb = 'bf-ecb';
$this->cipher_name_openssl = 'bf-' . $this->_openssl_translate_mode();
}
return parent::isValidEngine($engine);
}
/**
* Test for engine validity
*
* This is mainly just a wrapper to set things up for \phpseclib\Crypt\Base::isValidEngine()
*
* @see \phpseclib\Crypt\Base::__construct()
* @param int $engine
* @access public
* @return bool
*/
function isValidEngine($engine)
{
switch ($engine) {
case self::ENGINE_OPENSSL:
if ($this->block_size != 16) {
return false;
}
$this->cipher_name_openssl_ecb = 'aes-' . ($this->key_length << 3) . '-ecb';
$this->cipher_name_openssl = 'aes-' . ($this->key_length << 3) . '-' . $this->_openssl_translate_mode();
break;
case self::ENGINE_MCRYPT:
$this->cipher_name_mcrypt = 'rijndael-' . ($this->block_size << 3);
if ($this->key_length % 8) {
// is it a 160/224-bit key?
// mcrypt is not usable for them, only for 128/192/256-bit keys
return false;
}
}
return parent::isValidEngine($engine);
}