int ms_usage = mapArcfourMD5KeyUsage(keyusage);
        Mac mac = Mac.getInstance("HmacMD5");
        MessageDigest md = MessageDigest.getInstance("MD5");
        mac.init(key);
        byte[] dk = mac.doFinal(MD5_CONSTANT);
        try {
            // little endian
            md.update((byte) (ms_usage & 0xFF));

	}
	var (
		sealingKey   [32]byte
		encryptedKey bytes.Buffer
	)
	mac := hmac.New(sha256.New, extKey)
	mac.Write(iv[:])
	mac.Write([]byte(domain))
	mac.Write([]byte(SealAlgorithm))
	mac.Write([]byte(path.Join(bucket, object))) // use path.Join for canonical 'bucket/object'
	mac.Sum(sealingKey[:0])

            // Create new Mac instance for thread safety without blocking other operations
            Mac mac;
            try {
                mac = createMacInstance();
            } catch (GeneralSecurityException e) {
                log.error("Failed to create Mac instance for signing", e);
                throw new RuntimeException("Failed to create Mac instance", e);
            }

# ==============================================================================
#
# macOS specific setup for all TF scripts.
#

# Mac version of Core utilities differ in usage. Since our scripts are written
# with the GNU style, we need to set GNU utilities to be default on Mac.
if [[ -n "$(which grealpath)" ]] &&  [[ -n "$(which gstat)" ]]; then
  alias realpath=grealpath
  alias stat=gstat

        System.arraycopy(name.getBytes("US-ASCII"), 0, src, srcIndex + 13, 16);
        src[srcIndex + 28] = 0x00; // hex code
        src[srcIndex + 29] = 0x04; // flags
        // MAC address (6 bytes)
        byte[] mac = new byte[6];
        System.arraycopy(mac, 0, src, srcIndex + 31, 6);
        // Stats (6 bytes)
        byte[] stats = new byte[6];
        System.arraycopy(stats, 0, src, srcIndex + 37, 6);

	if err != nil {
		return nil, ErrDecrypt
	}
	return plaintext, nil
}

// MAC generate hmac for the request
func (s secretKey) MAC(_ context.Context, req *MACRequest) ([]byte, error) {
	mac := hmac.New(sha256.New, s.key)
	mac.Write(req.Message)
	return mac.Sum(make([]byte, 0, mac.Size())), nil
}

// parseCiphertext parses and converts a ciphertext into
// the format expected by a secretKey.

    private int updates;
    private int signSequence;

    /**
     * Constructs a new signing digest with the specified MAC signing key.
     *
     * @param macSigningKey the MAC signing key for message authentication
     * @param bypass whether to bypass MAC signing
     * @throws SmbException if MD5 algorithm is not available
     */

        // Using a key with a known value for reproducibility
        SecretKeySpec key = new SecretKeySpec(new byte[16], "ARCFOUR");
        byte[] mac = PacMac.calculateMacArcfourHMACMD5(3, key, TEST_DATA);
        assertNotNull(mac);
        assertEquals(16, mac.length);

        // Test with a different key usage
        byte[] mac2 = PacMac.calculateMacArcfourHMACMD5(9, key, TEST_DATA);
        assertNotNull(mac2);

        final byte[] seqBytes = new byte[4];
        SMBUtil.writeInt4(seqNum, seqBytes, 0);

        final MessageDigest mac = Crypto.getHMACT64(sk);
        mac.update(seqBytes); // sequence
        mac.update(data); // data
        final byte[] dgst = mac.digest();
        byte[] trunc = new byte[8];
        System.arraycopy(dgst, 0, trunc, 0, 8);

        if (log.isDebugEnabled()) {

   * @throws IllegalArgumentException if the given key is inappropriate for initializing this MAC
   * @since 20.0
   */
  public static HashFunction hmacMd5(Key key) {
    return new MacHashFunction("HmacMD5", key, hmacToString("hmacMd5", key));
  }

  /**
   * Returns a hash function implementing the Message Authentication Code (MAC) algorithm, using the