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()) {
            log.debug("Digest " + Hexdump.toHexString(dgst));
            log.debug("Truncated " + Hexdump.toHexString(trunc));
        }

    /**
     * Get an MD4 message digest instance.
     * @return MD4 digest instance
     */
    public static MessageDigest getMD4() {
        try {
            return MessageDigest.getInstance("MD4", getProvider());
        } catch (final NoSuchAlgorithmException e) {
            throw new CIFSUnsupportedCryptoException(e);
        }
    }

    /**
     * Get an MD5 message digest instance.
     * @return MD5 digest instance

                        }

                        uid = response.uid;

                        if (request.digest != null) {
                            /* success - install the signing digest */
                            transport.digest = request.digest;
                        }

                        connectionState = 2;

                        state = 0;

    private static final int SIGNATURE_LENGTH = 16;
    private final Mac digest;
    private final ReentrantLock signingLock = new ReentrantLock();
    private byte[] signingKey;
    private final String algorithmName;
    private final java.security.Provider provider;
    private volatile boolean closed = false;

    /**
     * Constructs a SMB2 signing digest with the specified session key and dialect
     *
     * @param sessionKey

    }

    /**
     * @param digest
     *            the digest to set
     * @throws SmbException
     */
    private void setDigest(SMBSigningDigest digest) throws SmbException {
        if (this.transport.isSMB2()) {
            this.digest = digest;
        } else {
            this.transport.setDigest(digest);
        }
    }

    /**
     * @return the digest

    }

    /**
     * @return the digest
     */
    @Override
    public final SMB1SigningDigest getDigest() {
        return this.digest;
    }

    /**
     * @param digest
     *            the digest to set
     */
    @Override
    public final void setDigest(final SMBSigningDigest digest) {
        this.digest = (SMB1SigningDigest) digest;
    }

    /**

        /** The desired access rights to the SAM server */
        public int access_mask;
        /** The returned handle to the SAM server */
        public rpc.policy_handle handle;

        /**
         * Constructs a SamrConnect2 request.
         *
         * @param system_name The NetBIOS name of the server
         * @param access_mask The desired access rights

        /** The desired access rights to the SAM server */
        public int access_mask;
        /** The returned handle to the SAM server */
        public rpc.policy_handle handle;

        /**
         * Constructs a SamrConnect2 request.
         *
         * @param system_name The NetBIOS name of the server
         * @param access_mask The desired access rights

    }

    @Test
    @DisplayName("isSignatureSetupRequired depends on digest and negotiate flags")
    void testIsSignatureSetupRequired() throws Exception {
        SmbSessionImpl session = newSession();

        // Case 1: digest already set -> false
        SMBSigningDigest dg = mock(SMBSigningDigest.class);
        setField(session, "digest", dg);
        assertFalse(session.isSignatureSetupRequired());

    }

    @Test
    @DisplayName("encode without andx succeeds and signs when digest present")
    void testEncodeNoAndxWithSigning() throws Exception {
        DummyAndXBlock block = new DummyAndXBlock();
        TestSigningDigest digest = new TestSigningDigest();
        block.digest = digest;

        byte[] buf = new byte[256];
        int len = block.encode(buf, 0);