protected function _paramsASN1()
{
$elements = array();
$elements[] = new OctetString($this->_specifiedSalt);
$elements[] = new Integer($this->_iterationCount);
if (isset($this->_keyLength)) {
$elements[] = new Integer($this->_keyLength);
}
if ($this->_prfAlgo->oid() !== AlgorithmIdentifier::OID_HMAC_WITH_SHA1) {
$elements[] = $this->_prfAlgo->toASN1();
}
return new Sequence(...$elements);
}
