/**
* Opens the module of the algorithm and the mode to be used
*
* This function opens the module of the algorithm and the mode to be used. The name of the algorithm
* is specified in algorithm, e.g. "twofish" or is one of the MCRYPT_ciphername constants. The module
* is closed by calling mcrypt_module_close().
*
* @param string $algorithm
* @param string $algorithm_directory
* @param string $mode
* @param string $mode_directory
* @return object
* @access public
*/
function phpseclib_mcrypt_module_open($algorithm, $algorithm_directory, $mode, $mode_directory)
{
$modeMap = array('ctr' => Base::MODE_CTR, 'ecb' => Base::MODE_ECB, 'cbc' => Base::MODE_CBC, 'ncfb' => Base::MODE_CFB, 'nofb' => Base::MODE_OFB, 'stream' => Base::MODE_STREAM);
switch (true) {
case !isset($modeMap[$mode]):
case $mode == 'stream' && $algorithm != 'arcfour':
case $algorithm == 'arcfour' && $mode != 'stream':
trigger_error('mcrypt_module_open(): Could not open encryption module', E_USER_WARNING);
return false;
}
switch ($algorithm) {
case 'rijndael-128':
$cipher = new phpseclib_mcrypt_rijndael($modeMap[$mode]);
$cipher->setBlockLength(128);
break;
case 'twofish':
$cipher = new Twofish($modeMap[$mode]);
break;
case 'rijndael-192':
$cipher = new phpseclib_mcrypt_rijndael($modeMap[$mode]);
$cipher->setBlockLength(192);
break;
case 'des':
$cipher = new DES($modeMap[$mode]);
break;
case 'rijndael-256':
$cipher = new phpseclib_mcrypt_rijndael($modeMap[$mode]);
$cipher->setBlockLength(256);
break;
case 'blowfish':
$cipher = new Blowfish($modeMap[$mode]);
break;
case 'rc2':
$cipher = new RC2($modeMap[$mode]);
break;
case 'tripledes':
$cipher = new TripleDES($modeMap[$mode]);
break;
case 'arcfour':
$cipher = new RC4();
break;
default:
trigger_error('mcrypt_module_open(): Could not open encryption module', E_USER_WARNING);
return false;
}
$cipher->disablePadding();
return $cipher;
}
