throw new CIFSException("No preauth integrity context found for session: " + sessionId);
            }
            log.warn("No preauth integrity context for session {}, skipping update", sessionId);
            return;
        }

        if (!context.isValid()) {
            throw new CIFSException("Preauth integrity context is invalid for session: " + sessionId);
        }

        try {

        init.setContextFlag(NegTokenInit.INTEGRITY, true);
        assertTrue(init.getContextFlag(NegTokenInit.INTEGRITY));
        assertEquals(NegTokenInit.CONFIDENTIALITY | NegTokenInit.INTEGRITY, init.getContextFlags());

        init.setContextFlag(NegTokenInit.CONFIDENTIALITY, false);
        assertFalse(init.getContextFlag(NegTokenInit.CONFIDENTIALITY));
        assertEquals(NegTokenInit.INTEGRITY, init.getContextFlags());
    }

        private ASN1ObjectIdentifier[] supportedMechs;
        private int flags;
        private boolean integrity;
        private boolean disposed;

        DummySSPContext(byte[] signingKey, boolean established, String nbName, ASN1ObjectIdentifier[] supportedMechs, int flags,
                boolean integrity) {
            this.signingKey = signingKey;
            this.established = established;
            this.nbName = nbName;

import jcifs.Configuration;
import jcifs.internal.SMBProtocolDecodingException;
import jcifs.internal.util.SMBUtil;

/**
 * SMB2 Pre-authentication Integrity Negotiate Context.
 *
 * This negotiate context is used in SMB 3.1.1 to establish
 * pre-authentication integrity protection against downgrade attacks.
 *
 * @author mbechler
 */

        transport = new SmbTransportImpl(context, address, 445, null, 0, false);
    }

    /**
     * Test that pre-auth integrity hash is properly synchronized
     */
    @Test
    @DisplayName("Pre-auth integrity hash should be thread-safe")
    void testPreauthHashThreadSafety() throws Exception {
        // Setup SMB3.1.1 negotiation

     */
    ASN1ObjectIdentifier[] getSupportedMechs();

    /**
     * Checks whether this mechanism supports message integrity.
     * @return whether this mechanisms supports integrity
     */
    boolean supportsIntegrity();

    /**
     * Calculates a Message Integrity Code (MIC) for the given data.
     * @param data the data to calculate MIC for
     * @return MIC

    }

    /**
     * Gets the mechanism list MIC (Message Integrity Code) for integrity protection
     * @return the mechanism list MIC bytes
     */
    public byte[] getMechanismListMIC() {
        return this.mechanismListMIC;
    }

    /**
     * Sets the mechanism list MIC (Message Integrity Code) for integrity protection
     * @param mechanismListMIC the mechanism list MIC bytes
     */

     *
     * @param dialect the SMB dialect version
     * @param sessionKey the base session key
     * @param preauthIntegrity the pre-authentication integrity hash (for SMB 3.1.1) or null
     * @return derived signing key
     */
    public static byte[] deriveSigningKey(final int dialect, final byte[] sessionKey, final byte[] preauthIntegrity) {

- **SMB 3.0**: Windows 8/Server 2012 (0x0300) - AES-128-CCM encryption
- **SMB 3.0.2**: Windows 8.1/Server 2012R2 (0x0302) - Enhanced encryption
- **SMB 3.1.1**: Windows 10/Server 2016+ (0x0311) - AES-128-GCM + Pre-Auth Integrity

**Protocol Selection:**
- Default Range: SMB1 to SMB 3.1.1
- Automatic Negotiation: Client offers all supported dialects, server selects highest common version

    /**
     * Context flag for confidentiality (encryption) capability
     */
    public static final int CONFIDENTIALITY = 0x04;
    /**
     * Context flag for integrity (signing) capability
     */
    public static final int INTEGRITY = 0x02;

    private static final ASN1ObjectIdentifier SPNEGO_OID = new ASN1ObjectIdentifier(SpnegoConstants.SPNEGO_MECHANISM);

    private ASN1ObjectIdentifier[] mechanisms;