/**
* Encrypt data.
*
* @param string $text Plaintext.
*
* @return array Array of MPI values (c1, c2).
*/
public function encrypt($text)
{
$p_len = strlen($this->_key->key['p']);
$length = $p_len - 11;
if ($length <= 0) {
return false;
}
$g = new Math_BigInteger($this->_key->key['g'], 256);
$p = new Math_BigInteger($this->_key->key['p'], 256);
$y = new Math_BigInteger($this->_key->key['y'], 256);
$out = array();
foreach (str_split($text, $length) as $m) {
// EME-PKCS1-v1_5 encoding
$psLen = $p_len - strlen($m) - 3;
$ps = '';
while (($psLen2 = strlen($ps)) != $psLen) {
$tmp = crypt_random_string($psLen - $psLen2);
$ps .= str_replace("", '', $tmp);
}
$em = new Math_BigInteger(chr(0) . chr(2) . $ps . chr(0) . $m, 256);
// End EME-PKCS1-v1_5 encoding
$k = Horde_Pgp_Crypt_DSA::randomNumber($p);
$c1 = $g->modPow($k, $p);
$c2_base = $y->modPow($k, $p)->multiply($em)->divide($p);
$c2 = $c2_base[1];
$out[] = str_pad($c1->toBytes(), $p_len, chr(0), STR_PAD_LEFT);
$out[] = str_pad($c2->toBytes(), $p_len, chr(0), STR_PAD_LEFT);
}
return $out;
}
/**
*/
public function verify($msg, $key)
{
$verify = new OpenPGP_Crypt_RSA($key->message);
$pkey = $verify->key();
switch ($pkey->algorithm) {
case 1:
case 2:
case 3:
// RSA
return $verify->verify($msg->message);
case 17:
// DSA
$dsa = new Horde_Pgp_Crypt_DSA($pkey);
$verifier = function ($m, $s) use($dsa) {
return $dsa->verify($m, Horde_String::lower($s->hash_algorithm_name()), new Math_BigInteger($s->data[0], 256), new Math_BigInteger($s->data[1], 256));
};
return $msg->message->verified_signatures(array('DSA' => array('MD5' => $verifier, 'SHA1' => $verifier, 'SHA224' => $verifier, 'SHA256' => $verifier, 'SHA384' => $verifier, 'SHA512' => $verifier)));
}
throw new RuntimeException();
}
