# Directory Leasing Feature - Detailed Design Document

## 1. Overview

Directory leasing extends the SMB3 lease concept to directories, enabling client-side caching of directory metadata and change notifications. This significantly improves performance for applications that frequently enumerate directories or monitor directory changes.

## 2. Protocol Specification Reference

- **MS-SMB2 Section 2.2.13.2.12**: SMB2_CREATE_REQUEST_LEASE_V2 for directories

   * specific length.
   *
   * <p>For example, if you need 1024-bit hash codes, you could join two {@link Hashing#sha512} hash
   * functions together: {@code Hashing.concatenating(Hashing.sha512(), Hashing.sha512())}.
   *
   * @since 19.0
   */
  public static HashFunction concatenating(
      HashFunction first, HashFunction second, HashFunction... rest) {

const (
	xMinIOHealing = ReservedMetadataPrefix + "healing"
	xMinIODataMov = ReservedMetadataPrefix + "data-mov"
)

// SetHealing marks object (version) as being healed.
// Note: this is to be used only from healObject
func (fi *FileInfo) SetHealing() {
	if fi.Metadata == nil {
		fi.Metadata = make(map[string]string)
	}
	fi.Metadata[xMinIOHealing] = "true"
}

            assertEquals(0x1, Smb2Constants.SMB2_GLOBAL_CAP_DFS, "DFS capability must be 0x1");
        }

        @Test
        @DisplayName("Leasing capability should be 0x2")
        void testGlobalCapLeasing() {
            assertEquals(0x2, Smb2Constants.SMB2_GLOBAL_CAP_LEASING, "Leasing capability must be 0x2");
        }

        @Test
        @DisplayName("Large MTU capability should be 0x4")

     * @return lease key
     */
    public Smb2LeaseKey requestDirectoryLease(String directoryPath, int requestedState, DirectoryCacheScope scope) {
        // Directory leasing requires SMB 3.0 or higher
        // MS-SMB2: Level 2 leasing (which includes directory leasing) is only supported in SMB 3.0+
        // We'll validate this when we actually need to use the session

        // Request base lease

- Update `SmbSession` for multi-channel awareness
- Enhance `SmbTransport` for channel management

---

### Phase 4: Directory Leasing
**Priority: MEDIUM** | **Estimated Effort: 2-3 weeks**

Directory leasing extends the lease concept to directories for improved metadata caching.

#### 4.1 Core Directory Lease Infrastructure
```
Package: jcifs.internal.smb2.lease

Klaus Post <******@****.***> 1756435188 +0200

// inspection to understand the root cause. E.g, this could be due to
// backend filesystem corruption.

// listOnlineDisks - returns
// - a slice of disks where disk having 'older' xl.meta (or nothing)
// are set to nil.
// - latest (in time) of the maximally occurring modTime(s), which has at least quorum occurrences.

- Delete one/some master keys. From a security standpoint, this is equal to erasing all SSE-S3 encrypted objects protected by these master keys. All these objects are lost forever as they cannot be decrypted. Especially deleting all master keys at the KMS is equivalent to secure erasing all SSE-S3 encrypted objects.

## Acronyms

- **AEAD**: Authenticated Encryption with Associated Data

                }
            } catch (NumberFormatException e) {
                // Invalid values ignored
            }
        }

        // Directory leasing configuration
        value = props.getProperty("jcifs.smb.client.useDirectoryLeasing");
        if (value != null) {
            this.useDirectoryLeasing = Boolean.parseBoolean(value);
        }