assertThrows(SmbUnsupportedOperationException.class, () -> transport.createEncryptionContext(new byte[] { 1 }, null));
        }

        @Test
        @DisplayName("createEncryptionContext rejects pre-SMB3 dialect")
        void createEncryptionContext_rejects_oldDialect() throws Exception {
            setField(transport, "smb2", true);
            Smb2NegotiateResponse nego = new Smb2NegotiateResponse(cfg);

            negotiate(altPort, resp);
            port = altPort;
        }

        if (resp.dialectIndex > 10) {
            throw new SmbException("This client does not support the negotiated dialect.");
        }
        if ((server.capabilities & CAP_EXTENDED_SECURITY) != CAP_EXTENDED_SECURITY && server.encryptionKeyLength != 8
                && LM_COMPATIBILITY == 0) {

    /**
     * SMB command to disconnect from a tree share.
     */
    public static final byte SMB_COM_TREE_DISCONNECT = (byte) 0x71;

    /**
     * SMB command to negotiate protocol dialect.
     */
    public static final byte SMB_COM_NEGOTIATE = (byte) 0x72;

    /**
     * SMB command to setup a session with extended attributes.
     */

# RDMA (SMB Direct) Feature - Detailed Design Document

## 1. Overview

SMB Direct enables high-performance data transfer using Remote Direct Memory Access (RDMA) technology. This provides ultra-low latency and high bandwidth data transfer by bypassing the traditional TCP/IP stack and allowing direct memory-to-memory transfers between client and server.

## 2. Protocol Specification Reference

- **MS-SMBD**: SMB2 Remote Direct Memory Access (RDMA) Transport Protocol

    @Override
    int writeBytesWireFormat(final byte[] dst, final int dstIndex) {
        byte[] dialects;
        try {
            dialects = DIALECTS.getBytes("ASCII");
        } catch (final UnsupportedEncodingException uee) {
            return 0;
        }
        System.arraycopy(dialects, 0, dst, dstIndex, dialects.length);
        return dialects.length;
    }

    @Override

package jcifs.internal.smb2.rdma;

import jcifs.internal.util.SMBUtil;

/**
 * SMB Direct Negotiate Response message.
 *
 * As per MS-SMBD 2.2.2 - SMB_DIRECT_NEGOTIATE_RESPONSE
 * This message is sent in response to negotiate SMB Direct protocol parameters.
 */
public class SmbDirectNegotiateResponse {

    // Protocol constants
    /** SMB Direct negotiate response message type */
    public static final int NEGOTIATE_RESPONSE = 0x02;

/**
 * SMB Direct Negotiate Request message.
 *
 * As per MS-SMBD 2.2.1 - SMB_DIRECT_NEGOTIATE_REQUEST
 * This message is sent to negotiate SMB Direct protocol parameters.
 */
public class SmbDirectNegotiateRequest {

    // Protocol constants
    /** Minimum supported SMB Direct protocol version (1.0) */
    public static final int MIN_VERSION = 0x0100; // SMB Direct 1.0

/**
 * RDMA capability flags indicating what operations are supported
 * by an RDMA provider implementation.
 */
public enum RdmaCapability {
    /**
     * Remote direct read operations
     */
    RDMA_READ,

    /**
     * Remote direct write operations
     */
    RDMA_WRITE,

    /**
     * Traditional send/receive with RDMA
     */
    RDMA_SEND_RECEIVE,

    /**

 * FILE_WRITE_DATA</code>) and the target file has the following security
 * descriptor ACEs:
 *
 * <pre>
 * Allow WNET\alice     0x001200A9  Direct
 * Allow Administrators 0x001F01FF  Inherited
 * Allow SYSTEM         0x001F01FF  Inherited
 * </pre>
 *
 * the access check would fail because the direct ACE has an access mask
 * of <code>0x001200A9</code> which doesn't have the

 * FILE_WRITE_DATA</code>) and the target file has the following security
 * descriptor ACEs:
 *
 * <pre>
 * Allow WNET\alice     0x001200A9  Direct
 * Allow Administrators 0x001F01FF  Inherited
 * Allow SYSTEM         0x001F01FF  Inherited
 * </pre>
 *
 * the access check would fail because the direct ACE has an access mask
 * of <code>0x001200A9</code> which doesn't have the