* reset.
     *
     * @return the array of bytes for the resulting hash value.
     */
    @Override
    public byte[] engineDigest() {
        // pad output to 56 mod 64; as RFC1320 puts it: congruent to 448 mod 512
        final int bufferNdx = (int) (count % BLOCK_LENGTH);
        final int padLen = bufferNdx < 56 ? 56 - bufferNdx : 120 - bufferNdx;

        // padding is alwas binary 1 followed by binary 0s