/**
* Sets the key.
*
* Rijndael supports five different key lengths
*
* @see setKeyLength()
* @access public
* @param string $key
* @throws \LengthException if the key length isn't supported
*/
function setKey($key)
{
switch (strlen($key)) {
case 16:
case 24:
case 32:
break;
default:
throw new \LengthException('Key of size ' . strlen($key) . ' not supported by this algorithm. Only keys of sizes 16, 24 or 32 supported');
}
parent::setKey($key);
}
/**
* Sets the key.
*
* Keys can be of any length. RC2, itself, uses 8 to 1024 bit keys (eg.
* strlen($key) <= 128), however, we only use the first 128 bytes if $key
* has more then 128 bytes in it, and set $key to a single null byte if
* it is empty.
*
* If the key is not explicitly set, it'll be assumed to be a single
* null byte.
*
* @see \phpseclib\Crypt\Common\SymmetricKey::setKey()
* @access public
* @param string $key
* @param int $t1 optional Effective key length in bits.
* @throws \LengthException if the key length isn't supported
*/
function setKey($key, $t1 = false)
{
$this->orig_key = $key;
if ($t1 === false) {
$t1 = $this->default_key_length;
}
if ($t1 < 1 || $t1 > 1024) {
throw new \LengthException('Key size of ' . $length . ' bits is not supported by this algorithm. Only keys between 1 and 1024 bits, inclusive, are supported');
}
$this->current_key_length = $t1;
// Key byte count should be 1..128.
$key = strlen($key) ? substr($key, 0, 128) : "";
$t = strlen($key);
// The mcrypt RC2 implementation only supports effective key length
// of 1024 bits. It is however possible to handle effective key
// lengths in range 1..1024 by expanding the key and applying
// inverse pitable mapping to the first byte before submitting it
// to mcrypt.
// Key expansion.
$l = array_values(unpack('C*', $key));
$t8 = $t1 + 7 >> 3;
$tm = 0xff >> 8 * $t8 - $t1;
// Expand key.
$pitable = $this->pitable;
for ($i = $t; $i < 128; $i++) {
$l[$i] = $pitable[$l[$i - 1] + $l[$i - $t]];
}
$i = 128 - $t8;
$l[$i] = $pitable[$l[$i] & $tm];
while ($i--) {
$l[$i] = $pitable[$l[$i + 1] ^ $l[$i + $t8]];
}
// Prepare the key for mcrypt.
$l[0] = $this->invpitable[$l[0]];
array_unshift($l, 'C*');
parent::setKey(call_user_func_array('pack', $l));
}
