return md5.getDigestLength();
    }

    protected void engineReset() {
        md5.reset();
        md5.update(ipad);
    }

    protected void engineUpdate(byte b) {
        md5.update(b);
    }

    protected void engineUpdate(byte[] input, int offset, int len) {
        md5.update(input, offset, len);
    }

    protected void engineReset () {
        this.md5.reset();
        this.md5.update(this.ipad);
    }


    @Override
    protected void engineUpdate ( byte b ) {
        this.md5.update(b);
    }


    @Override
    protected void engineUpdate ( byte[] input, int offset, int len ) {
        this.md5.update(input, offset, len);
    }

        count = 0L;
        for (int i = 0; i < BLOCK_LENGTH; i++)
            buffer[i] = 0;
    }

    /**
     * Continues an MD4 message digest using the input byte.
     */
    public void engineUpdate (byte b) {
        // compute number of bytes still unhashed; ie. present in buffer
        int i = (int)(count % BLOCK_LENGTH);
        count++;                                        // update number of bytes