/**
* Convert a private key to the appropriate format.
*
* @access public
* @param \phpseclib\Math\BigInteger $n
* @param \phpseclib\Math\BigInteger $e
* @param \phpseclib\Math\BigInteger $d
* @param array $primes
* @param array $exponents
* @param array $coefficients
* @param string $password optional
* @return string
*/
static function savePrivateKey(BigInteger $n, BigInteger $e, BigInteger $d, $primes, $exponents, $coefficients, $password = '')
{
if (count($primes) != 2) {
return false;
}
$raw = array('modulus' => $n->toBytes(true), 'publicExponent' => $e->toBytes(true), 'privateExponent' => $d->toBytes(true), 'prime1' => $primes[1]->toBytes(true), 'prime2' => $primes[2]->toBytes(true), 'exponent1' => $exponents[1]->toBytes(true), 'exponent2' => $exponents[2]->toBytes(true), 'coefficient' => $coefficients[2]->toBytes(true));
$key = "PuTTY-User-Key-File-2: ssh-rsa\r\nEncryption: ";
$encryption = !empty($password) || is_string($password) ? 'aes256-cbc' : 'none';
$key .= $encryption;
$key .= "\r\nComment: " . self::$comment . "\r\n";
$public = pack('Na*Na*Na*', strlen('ssh-rsa'), 'ssh-rsa', strlen($raw['publicExponent']), $raw['publicExponent'], strlen($raw['modulus']), $raw['modulus']);
$source = pack('Na*Na*Na*Na*', strlen('ssh-rsa'), 'ssh-rsa', strlen($encryption), $encryption, strlen(self::$comment), self::$comment, strlen($public), $public);
$public = Base64::encode($public);
$key .= "Public-Lines: " . (strlen($public) + 63 >> 6) . "\r\n";
$key .= chunk_split($public, 64);
$private = pack('Na*Na*Na*Na*', strlen($raw['privateExponent']), $raw['privateExponent'], strlen($raw['prime1']), $raw['prime1'], strlen($raw['prime2']), $raw['prime2'], strlen($raw['coefficient']), $raw['coefficient']);
if (empty($password) && !is_string($password)) {
$source .= pack('Na*', strlen($private), $private);
$hashkey = 'putty-private-key-file-mac-key';
} else {
$private .= Random::string(16 - (strlen($private) & 15));
$source .= pack('Na*', strlen($private), $private);
$crypto = new AES();
$crypto->setKey(static::generateSymmetricKey($password, 32));
$crypto->setIV(str_repeat("", $crypto->getBlockLength() >> 3));
$crypto->disablePadding();
$private = $crypto->encrypt($private);
$hashkey = 'putty-private-key-file-mac-key' . $password;
}
$private = Base64::encode($private);
$key .= 'Private-Lines: ' . (strlen($private) + 63 >> 6) . "\r\n";
$key .= chunk_split($private, 64);
$hash = new Hash('sha1');
$hash->setKey(sha1($hashkey, true));
$key .= 'Private-MAC: ' . Hex::encode($hash->hash($source)) . "\r\n";
return $key;
}