# 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

/**
 * 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

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;

 * </ul>
 *
 * <p>The main purpose of {@link #addListener addListener} is to support this chaining. You will
 * rarely use it directly, in part because it does not provide direct access to the {@code Future}
 * result. (If you want such access, you may prefer {@link Futures#addCallback
 * Futures.addCallback}.) Still, direct {@code addListener} calls are occasionally useful:
 *
 * {@snippet :
 * final String name = ...;
 * inFlight.add(name);

      .assertLogMatch(Regex("""proxySelectEnd: \[DIRECT]"""))
      .assertLogMatch(Regex("""dnsStart: ${url.host}"""))
      .assertLogMatch(Regex("""dnsEnd: \[.+]"""))
      .assertLogMatch(Regex("""connectStart: ${url.host}/.+ DIRECT"""))
      .assertLogMatch(Regex("""connectEnd: http/1.1"""))
      .assertLogMatch(
        Regex(

 * 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

    }

    public void test_idFieldAccess() {
        // Test direct field access through inheritance
        TestDictionaryItem item = new TestDictionaryItem();

        // Direct field assignment
        item.id = 999L;

        // Verify through getter
        assertEquals(999L, item.getId());

        // Verify direct field access
        assertEquals(999L, item.id);
    }

/**
 * 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,

    /**

      other entities that control, are controlled by, or are under common
      control with that entity. For the purposes of this definition,
      "control" means (i) the power, direct or indirect, to cause the
      direction or management of such entity, whether by contract or
      otherwise, or (ii) ownership of fifty percent (50%) or more of the
      outstanding shares, or (iii) beneficial ownership of such entity.

   * use the {@code HashSet} constructor directly, taking advantage of <a
   * href="https://docs.oracle.com/javase/tutorial/java/generics/genTypeInference.html#type-inference-instantiation">"diamond"
   * syntax</a>.
   */
  @SuppressWarnings("NonApiType") // acts as a direct substitute for a constructor call
  public static <E extends @Nullable Object> HashSet<E> newHashSet() {