throw new SmbUnsupportedOperationException();
        }

        MessageDigest dgst;
        switch ( resp.getSelectedPreauthHash() ) {
        case 1:
            dgst = Crypto.getSHA512();
            break;
        default:
            throw new SmbUnsupportedOperationException();
        }

        if ( oldHash != null ) {
            dgst.update(oldHash);
        }