Internet Engineering Task Force (IETF)                    D. Noveck, Ed.
Request for Comments: 8881                                        NetApp
Obsoletes: 5661                                                 C. Lever
Category: Standards Track                                         ORACLE
ISSN: 2070-1721                                              August 2020

Network File System (NFS) Version 4 Minor Version 1 Protocol




This document describes the Network File System (NFS) version 4 minor version 1, including features retained from the base protocol (NFS version 4 minor version 0, which is specified in RFC 7530) and protocol extensions made subsequently. The later minor version has no dependencies on NFS version 4 minor version 0, and is considered a separate protocol.

このドキュメントでは、基本プロトコル(RFC 7530で指定されているNFSバージョン4マイナーバージョン0)から保持されている機能を含む、ネットワークファイルシステム(NFS)バージョン4マイナーバージョン1と、その後に作成されたプロトコル拡張機能について説明します。後のマイナーバージョンは、NFSバージョン4マイナーバージョン0に依存しません。また、別のプロトコルと見なされます。

This document obsoletes RFC 5661. It substantially revises the treatment of features relating to multi-server namespace, superseding the description of those features appearing in RFC 5661.

この文書はRFC 5661を廃止します.RFC 5661に表示される機能の説明に置き換えられているマルチサーバーネームスペースに関連する機能の扱いを実質的に修正します。

Status of This Memo


This is an Internet Standards Track document.


This document is a product of the Internet Engineering Task Force (IETF). It represents the consensus of the IETF community. It has received public review and has been approved for publication by the Internet Engineering Steering Group (IESG). Further information on Internet Standards is available in Section 2 of RFC 7841.

この文書は、インターネットエンジニアリングタスクフォース(IETF)の製品です。IETFコミュニティのコンセンサスを表します。それは公開レビューを受け、インターネットエンジニアリングステアリンググループ(IESG)による出版の承認を受けました。インターネット規格に関する詳細情報は、RFC 7841のセクション2で利用できます。

Information about the current status of this document, any errata, and how to provide feedback on it may be obtained at


Copyright Notice


Copyright (c) 2020 IETF Trust and the persons identified as the document authors. All rights reserved.

Copyright(C)2020 IETFの信頼と文書著者として識別された人。全著作権所有。

This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents ( in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License.

この文書は、この文書の公開日に有効なIETF文書(に関するBCP 78とIETF信頼の法的規定を受けています。この文書に関してあなたの権利と制限を説明するので、これらの文書を慎重に見直してください。この文書から抽出されたコードコンポーネントには、信頼法の法的規定のセクション4。

This document may contain material from IETF Documents or IETF Contributions published or made publicly available before November 10, 2008. The person(s) controlling the copyright in some of this material may not have granted the IETF Trust the right to allow modifications of such material outside the IETF Standards Process. Without obtaining an adequate license from the person(s) controlling the copyright in such materials, this document may not be modified outside the IETF Standards Process, and derivative works of it may not be created outside the IETF Standards Process, except to format it for publication as an RFC or to translate it into languages other than English.


Table of Contents


   1.  Introduction
     1.1.  Introduction to This Update
     1.2.  The NFS Version 4 Minor Version 1 Protocol
     1.3.  Requirements Language
     1.4.  Scope of This Document
     1.5.  NFSv4 Goals
     1.6.  NFSv4.1 Goals
     1.7.  General Definitions
     1.8.  Overview of NFSv4.1 Features
     1.9.  Differences from NFSv4.0
   2.  Core Infrastructure
     2.1.  Introduction
     2.2.  RPC and XDR
     2.4.  Client Identifiers and Client Owners
     2.5.  Server Owners
     2.6.  Security Service Negotiation
     2.7.  Minor Versioning
     2.8.  Non-RPC-Based Security Services
     2.9.  Transport Layers
     2.10. Session
   3.  Protocol Constants and Data Types
     3.1.  Basic Constants
     3.2.  Basic Data Types
     3.3.  Structured Data Types
   4.  Filehandles
     4.1.  Obtaining the First Filehandle
     4.2.  Filehandle Types
     4.3.  One Method of Constructing a Volatile Filehandle
     4.4.  Client Recovery from Filehandle Expiration
   5.  File Attributes
     5.1.  REQUIRED Attributes
     5.2.  RECOMMENDED Attributes
     5.3.  Named Attributes
     5.4.  Classification of Attributes
     5.5.  Set-Only and Get-Only Attributes
     5.6.  REQUIRED Attributes - List and Definition References
     5.7.  RECOMMENDED Attributes - List and Definition References
     5.8.  Attribute Definitions
     5.9.  Interpreting owner and owner_group
     5.10. Character Case Attributes
     5.11. Directory Notification Attributes
     5.12. pNFS Attribute Definitions
     5.13. Retention Attributes
   6.  Access Control Attributes
     6.1.  Goals
     6.2.  File Attributes Discussion
     6.3.  Common Methods
     6.4.  Requirements
   7.  Single-Server Namespace
     7.1.  Server Exports
     7.2.  Browsing Exports
     7.3.  Server Pseudo File System
     7.4.  Multiple Roots
     7.5.  Filehandle Volatility
     7.6.  Exported Root
     7.7.  Mount Point Crossing
     7.8.  Security Policy and Namespace Presentation
   8.  State Management
     8.1.  Client and Session ID
     8.2.  Stateid Definition
     8.3.  Lease Renewal
     8.4.  Crash Recovery
     8.5.  Server Revocation of Locks
     8.6.  Short and Long Leases
     8.7.  Clocks, Propagation Delay, and Calculating Lease Expiration
     8.8.  Obsolete Locking Infrastructure from NFSv4.0
   9.  File Locking and Share Reservations
     9.1.  Opens and Byte-Range Locks
     9.2.  Lock Ranges
     9.3.  Upgrading and Downgrading Locks
     9.4.  Stateid Seqid Values and Byte-Range Locks
     9.5.  Issues with Multiple Open-Owners
     9.6.  Blocking Locks
     9.7.  Share Reservations
     9.8.  OPEN/CLOSE Operations
     9.9.  Open Upgrade and Downgrade
     9.10. Parallel OPENs
     9.11. Reclaim of Open and Byte-Range Locks
   10. Client-Side Caching
     10.1.  Performance Challenges for Client-Side Caching
     10.2.  Delegation and Callbacks
     10.3.  Data Caching
     10.4.  Open Delegation
     10.5.  Data Caching and Revocation
     10.6.  Attribute Caching
     10.7.  Data and Metadata Caching and Memory Mapped Files
     10.8.  Name and Directory Caching without Directory Delegations
     10.9.  Directory Delegations
   11. Multi-Server Namespace
     11.1.  Terminology
     11.2.  File System Location Attributes
     11.3.  File System Presence or Absence
     11.4.  Getting Attributes for an Absent File System
     11.5.  Uses of File System Location Information
     11.6.  Trunking without File System Location Information
     11.7.  Users and Groups in a Multi-Server Namespace
     11.8.  Additional Client-Side Considerations
     11.9.  Overview of File Access Transitions
     11.10. Effecting Network Endpoint Transitions
     11.11. Effecting File System Transitions
     11.12. Transferring State upon Migration
     11.13. Client Responsibilities When Access Is Transitioned
     11.14. Server Responsibilities Upon Migration
     11.15. Effecting File System Referrals
     11.16. The Attribute fs_locations
     11.17. The Attribute fs_locations_info
     11.18. The Attribute fs_status
   12. Parallel NFS (pNFS)
     12.1.  Introduction
     12.2.  pNFS Definitions
     12.3.  pNFS Operations
     12.4.  pNFS Attributes
     12.5.  Layout Semantics
     12.6.  pNFS Mechanics
     12.7.  Recovery
     12.8.  Metadata and Storage Device Roles
     12.9.  Security Considerations for pNFS
   13. NFSv4.1 as a Storage Protocol in pNFS: the File Layout Type
     13.1.  Client ID and Session Considerations
     13.2.  File Layout Definitions
     13.3.  File Layout Data Types
     13.4.  Interpreting the File Layout
     13.5.  Data Server Multipathing
     13.6.  Operations Sent to NFSv4.1 Data Servers
     13.7.  COMMIT through Metadata Server
     13.8.  The Layout Iomode
     13.9.  Metadata and Data Server State Coordination
     13.10. Data Server Component File Size
     13.11. Layout Revocation and Fencing
     13.12. Security Considerations for the File Layout Type
   14. Internationalization
     14.1.  Stringprep Profile for the utf8str_cs Type
     14.2.  Stringprep Profile for the utf8str_cis Type
     14.3.  Stringprep Profile for the utf8str_mixed Type
     14.4.  UTF-8 Capabilities
     14.5.  UTF-8 Related Errors
   15. Error Values
     15.1.  Error Definitions
     15.2.  Operations and Their Valid Errors
     15.3.  Callback Operations and Their Valid Errors
     15.4.  Errors and the Operations That Use Them
   16. NFSv4.1 Procedures
     16.1.  Procedure 0: NULL - No Operation
     16.2.  Procedure 1: COMPOUND - Compound Operations
   18. NFSv4.1 Operations
     18.1.  Operation 3: ACCESS - Check Access Rights
     18.2.  Operation 4: CLOSE - Close File
     18.3.  Operation 5: COMMIT - Commit Cached Data
     18.4.  Operation 6: CREATE - Create a Non-Regular File Object
     18.5.  Operation 7: DELEGPURGE - Purge Delegations Awaiting
     18.6.  Operation 8: DELEGRETURN - Return Delegation
     18.7.  Operation 9: GETATTR - Get Attributes
     18.8.  Operation 10: GETFH - Get Current Filehandle
     18.9.  Operation 11: LINK - Create Link to a File
     18.10. Operation 12: LOCK - Create Lock
     18.11. Operation 13: LOCKT - Test for Lock
     18.12. Operation 14: LOCKU - Unlock File
     18.13. Operation 15: LOOKUP - Lookup Filename
     18.14. Operation 16: LOOKUPP - Lookup Parent Directory
     18.15. Operation 17: NVERIFY - Verify Difference in Attributes
     18.16. Operation 18: OPEN - Open a Regular File
     18.17. Operation 19: OPENATTR - Open Named Attribute Directory
     18.18. Operation 21: OPEN_DOWNGRADE - Reduce Open File Access
     18.19. Operation 22: PUTFH - Set Current Filehandle
     18.20. Operation 23: PUTPUBFH - Set Public Filehandle
     18.21. Operation 24: PUTROOTFH - Set Root Filehandle
     18.22. Operation 25: READ - Read from File
     18.23. Operation 26: READDIR - Read Directory
     18.24. Operation 27: READLINK - Read Symbolic Link
     18.25. Operation 28: REMOVE - Remove File System Object
     18.26. Operation 29: RENAME - Rename Directory Entry
     18.27. Operation 31: RESTOREFH - Restore Saved Filehandle
     18.28. Operation 32: SAVEFH - Save Current Filehandle
     18.29. Operation 33: SECINFO - Obtain Available Security
     18.30. Operation 34: SETATTR - Set Attributes
     18.31. Operation 37: VERIFY - Verify Same Attributes
     18.32. Operation 38: WRITE - Write to File
     18.33. Operation 40: BACKCHANNEL_CTL - Backchannel Control
     18.34. Operation 41: BIND_CONN_TO_SESSION - Associate Connection
             with Session
     18.35. Operation 42: EXCHANGE_ID - Instantiate Client ID
     18.36. Operation 43: CREATE_SESSION - Create New Session and
             Confirm Client ID
     18.37. Operation 44: DESTROY_SESSION - Destroy a Session
     18.38. Operation 45: FREE_STATEID - Free Stateid with No Locks
     18.39. Operation 46: GET_DIR_DELEGATION - Get a Directory
     18.40. Operation 47: GETDEVICEINFO - Get Device Information
     18.41. Operation 48: GETDEVICELIST - Get All Device Mappings for
             a File System
     18.42. Operation 49: LAYOUTCOMMIT - Commit Writes Made Using a
     18.43. Operation 50: LAYOUTGET - Get Layout Information
     18.44. Operation 51: LAYOUTRETURN - Release Layout Information
     18.45. Operation 52: SECINFO_NO_NAME - Get Security on Unnamed
     18.46. Operation 53: SEQUENCE - Supply Per-Procedure Sequencing
             and Control
     18.47. Operation 54: SET_SSV - Update SSV for a Client ID
     18.48. Operation 55: TEST_STATEID - Test Stateids for Validity
     18.49. Operation 56: WANT_DELEGATION - Request Delegation
     18.50. Operation 57: DESTROY_CLIENTID - Destroy a Client ID
     18.51. Operation 58: RECLAIM_COMPLETE - Indicates Reclaims
     18.52. Operation 10044: ILLEGAL - Illegal Operation
   19. NFSv4.1 Callback Procedures
     19.1.  Procedure 0: CB_NULL - No Operation
     19.2.  Procedure 1: CB_COMPOUND - Compound Operations
   20. NFSv4.1 Callback Operations
     20.1.  Operation 3: CB_GETATTR - Get Attributes
     20.2.  Operation 4: CB_RECALL - Recall a Delegation
     20.3.  Operation 5: CB_LAYOUTRECALL - Recall Layout from Client
     20.4.  Operation 6: CB_NOTIFY - Notify Client of Directory
     20.5.  Operation 7: CB_PUSH_DELEG - Offer Previously Requested
             Delegation to Client
     20.6.  Operation 8: CB_RECALL_ANY - Keep Any N Recallable Objects
     20.7.  Operation 9: CB_RECALLABLE_OBJ_AVAIL - Signal Resources
             for Recallable Objects
     20.8.  Operation 10: CB_RECALL_SLOT - Change Flow Control Limits
     20.9.  Operation 11: CB_SEQUENCE - Supply Backchannel Sequencing
             and Control
     20.10. Operation 12: CB_WANTS_CANCELLED - Cancel Pending
             Delegation Wants
     20.11. Operation 13: CB_NOTIFY_LOCK - Notify Client of Possible
             Lock Availability
     20.12. Operation 14: CB_NOTIFY_DEVICEID - Notify Client of Device
             ID Changes
     20.13. Operation 10044: CB_ILLEGAL - Illegal Callback Operation
   21. Security Considerations
   22. IANA Considerations
     22.1.  IANA Actions
     22.2.  Named Attribute Definitions
     22.3.  Device ID Notifications
     22.4.  Object Recall Types
     22.5.  Layout Types
     22.6.  Path Variable Definitions
   23. References
     23.1.  Normative References
     23.2.  Informative References
   Appendix A.  The Need for This Update
   Appendix B.  Changes in This Update
     B.1.  Revisions Made to Section 11 of RFC 5661
     B.2.  Revisions Made to Operations in RFC 5661
     B.3.  Revisions Made to Error Definitions in RFC 5661
     B.4.  Other Revisions Made to RFC 5661
   Appendix C.  Security Issues That Need to Be Addressed
   Authors' Addresses
1. Introduction
1. はじめに
1.1. Introduction to This Update
1.1. このアップデートの紹介

Two important features previously defined in minor version 0 but never fully addressed in minor version 1 are trunking, which is the simultaneous use of multiple connections between a client and server, potentially to different network addresses, and Transparent State Migration, which allows a file system to be transferred between servers in a way that provides to the client the ability to maintain its existing locking state across the transfer.


The revised description of the NFS version 4 minor version 1 (NFSv4.1) protocol presented in this update is necessary to enable full use of these features together with other multi-server namespace features. This document is in the form of an updated description of the NFSv4.1 protocol previously defined in RFC 5661 [66]. RFC 5661 is obsoleted by this document. However, the update has a limited scope and is focused on enabling full use of trunking and Transparent State Migration. The need for these changes is discussed in Appendix A. Appendix B describes the specific changes made to arrive at the current text.

このアップデートで提示されているNFSバージョン4マイナーバージョン1(NFSV4.1)プロトコルの改訂された説明は、これらの機能を他のマルチサーバーネームスペース機能と一緒に完全に使用できるようにする必要があります。このドキュメントは、RFC 5661 [66]で以前に定義されているNFSV4.1プロトコルの更新された説明の形式です。RFC 5661はこの文書によって廃止されています。ただし、このアップデートには限られた範囲があり、トランキングと透過状態の移行を最大限に活用することができます。これらの変更の必要性は付録Aで説明されています。付録Bは、現在のテキストに到着するように行われた特定の変更を示しています。

This limited-scope update replaces the current NFSv4.1 RFC with the intention of providing an authoritative and complete specification, the motivation for which is discussed in [36], addressing the issues within the scope of the update. However, it will not address issues that are known but outside of this limited scope as could be expected by a full update of the protocol. Below are some areas that are known to need addressing in a future update of the protocol:

この限られたスコープの更新は、現在のNFSV4.1 RFCを、正式で完全な仕様を提供することを意図して、[36]で説明されているモチベーションを更新の範囲内の問題に対処することを目的としています。ただし、プロトコルの完全な更新によって予想されるように、既知の問題に対処することはありません。以下は、将来のプロトコルの更新でアドレス指定が必要ないくつかの分野です。

* Work needs to be done with regard to RFC 8178 [67], which establishes NFSv4-wide versioning rules. As RFC 5661 is currently inconsistent with that document, changes are needed in order to arrive at a situation in which there would be no need for RFC 8178 to update the NFSv4.1 specification.

* NFSV4全体のバージョン管理規則を確立するRFC 8178 [67]に関して作業を行う必要があります。RFC 5661が現在その文書と矛盾しているので、RFC 8178がNFSV4.1の仕様を更新する必要がない状況に到着するために変更が必要です。

* Work needs to be done with regard to RFC 8434 [70], which establishes the requirements for parallel NFS (pNFS) layout types, which are not clearly defined in RFC 5661. When that work is done and the resulting documents approved, the new NFSv4.1 specification document will provide a clear set of requirements for layout types and a description of the file layout type that conforms to those requirements. Other layout types will have their own specification documents that conform to those requirements as well.

* RFC 8434 [70]に関しては、RFC 5661では明確に定義されていない並列NFS(PNFS)レイアウトタイプの要件が確立されるRFC 8434 [70]に関して行う必要があります。その作業が行われ、結果として得られる文書が新しいNFSV4.1仕様書は、レイアウトタイプのための明確な要件とそれらの要件に準拠したファイルレイアウト型の説明を提供します。他のレイアウトタイプには、それらの要件にも適合する独自の仕様書があります。

* Work needs to be done to address many errata reports relevant to RFC 5661, other than errata report 2006 [64], which is addressed in this document. Addressing that report was not deferrable because of the interaction of the changes suggested there and the newly described handling of state and session migration.

* このドキュメントで対処されているErrata Report 2006 [64]以外のRFC 5661に関連する多くのエラータレポートに対処するために、作業を行う必要があります。その変更の相互作用が推奨されていないことに対処し、そこに示唆された変更と、新しく説明された状態の移行とセッションの移行の取り扱いが延期されました。

The errata reports that have been deferred and that will need to be addressed in a later document include reports currently assigned a range of statuses in the errata reporting system, including reports marked Accepted and those marked Hold For Document Update because the change was too minor to address immediately.


In addition, there is a set of other reports, including at least one in state Rejected, that will need to be addressed in a later document. This will involve making changes to consensus decisions reflected in RFC 5661, in situations in which the working group has decided that the treatment in RFC 5661 is incorrect and needs to be revised to reflect the working group's new consensus and to ensure compatibility with existing implementations that do not follow the handling described in RFC 5661.

さらに、少なくとも1つの状態を含む他のレポートのセットがあります。これにより、後の文書でアドレス指定する必要があります。これは、RFC 5661に反映されているコンセンサス決定を変更することを含み、ワーキンググループがRFC 5661の治療が正しくないと判断し、ワーキンググループの新しいコンセンサスを反映し、既存の実装との互換性を確保する必要がある状況では、RFC 5661に変更を加えることが含まれます。RFC 5661に記載されている取り扱いに従わないでください。

Note that it is expected that all such errata reports will remain relevant to implementors and the authors of an eventual rfc5661bis, despite the fact that this document obsoletes RFC 5661 [66].

この文書がRFC 5661を廃止されているという事実にもかかわらず、そのようなエラータレポートはすべて実装者および最終的なRFC5661BISの著者に関連したままになると予想されることに注意してください。

* There is a need for a new approach to the description of internationalization since the current internationalization section (Section 14) has never been implemented and does not meet the needs of the NFSv4 protocol. Possible solutions are to create a new internationalization section modeled on that in [68] or to create a new document describing internationalization for all NFSv4 minor versions and reference that document in the RFCs defining both NFSv4.0 and NFSv4.1.

* 現在の国際化セクション(セクション14)が実装されたことがなく、NFSV4プロトコルのニーズを満たしていないため、国際化の説明への新しいアプローチが必要とされています。考えられる解決策は、[68]でモデル化された新しい国際化セクションを作成したり、すべてのNFSV4マイナーバージョンの国際化を説明し、NFSV4.0とNFSV4.1の両方を定義するRFCSの文書を参照してください。

* There is a need for a revised treatment of security in NFSv4.1. The issues with the existing treatment are discussed in Appendix C.

* NFSV4.1のセキュリティの修正治療が必要です。既存の治療の問題は付録Cで議論されています。

Until the above work is done, there will not be a consistent set of documents that provides a description of the NFSv4.1 protocol, and any full description would involve documents updating other documents within the specification. The updates applied by RFC 8434 [70] and RFC 8178 [67] to RFC 5661 also apply to this specification, and will apply to any subsequent v4.1 specification until that work is done.

上記の作業が行われるまで、NFSV4.1プロトコルの説明を提供する一貫した文書のセットはありません。また、詳細な説明は、仕様内の他の文書を更新する文書を含みます。RFC 8434 [70]とRFC 8178 [67]からRFC 5661に適用された更新プログラムは、この仕様にも適用され、その作業が行われるまでの任意の後続のV4.1仕様に適用されます。

1.2. The NFS Version 4 Minor Version 1 Protocol
1.2. NFSバージョン4マイナーバージョン1プロトコル

The NFS version 4 minor version 1 (NFSv4.1) protocol is the second minor version of the NFS version 4 (NFSv4) protocol. The first minor version, NFSv4.0, is now described in RFC 7530 [68]. It generally follows the guidelines for minor versioning that are listed in Section 10 of RFC 3530 [37]. However, it diverges from guidelines 11 ("a client and server that support minor version X must support minor versions 0 through X-1") and 12 ("no new features may be introduced as mandatory in a minor version"). These divergences are due to the introduction of the sessions model for managing non-idempotent operations and the RECLAIM_COMPLETE operation. These two new features are infrastructural in nature and simplify implementation of existing and other new features. Making them anything but REQUIRED would add undue complexity to protocol definition and implementation. NFSv4.1 accordingly updates the minor versioning guidelines (Section 2.7).

NFSバージョン4マイナーバージョン1(NFSV4.1)プロトコルは、NFSバージョン4(NFSV4)プロトコルの2番目のマイナーバージョンです。最初のマイナーバージョンNFSV4.0は、RFC 7530 [68]で説明されています。それは一般的にRFC 3530のセクション10にリストされているマイナーバージョン管理のガイドラインに従います。ただし、ガイドライン11(「マイナーバージョンXをサポートするクライアントとサーバーは、マイナーバージョン0からX-1」をサポートしている必要があります)と12(マイナーバージョンでは必須の新しい機能は導入されない可能性があります)から分岐します。これらの分岐は、非イデボータ操作操作およびRECLAIM_COMPLETE操作を管理するためのセッションモデルの導入によるものです。これら2つの新機能は、本質的にインフラストラクチャーであり、既存およびその他の新機能の実装を簡素化しています。必要があるが必要とされるが、プロトコルの定義および実装に過度の複雑さを追加するであろう。NFSV4.1により、マイナーバージョン管理ガイドラインを更新します(セクション2.7)。

As a minor version, NFSv4.1 is consistent with the overall goals for NFSv4, but extends the protocol so as to better meet those goals, based on experiences with NFSv4.0. In addition, NFSv4.1 has adopted some additional goals, which motivate some of the major extensions in NFSv4.1.


1.3. Requirements Language
1.3. 要件言語

The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in RFC 2119 [1].

「必須」、「必須」、「必要ではない」、「しない」、「推奨する」、「推奨する」、「5月」、および「オプション」、「オプション」、「オプション」、「オプション」、「オプション」、「オプション」、RFC 2119 [1]に記載されているように解釈されること。

1.4. Scope of This Document
1.4. この文書の範囲

This document describes the NFSv4.1 protocol. With respect to NFSv4.0, this document does not:


* describe the NFSv4.0 protocol, except where needed to contrast with NFSv4.1.

* NFSV4.1とは対照的に必要な場合を除き、NFSV4.0プロトコルを説明します。

* modify the specification of the NFSv4.0 protocol.

* NFSv4.0プロトコルの指定を変更します。

* clarify the NFSv4.0 protocol.

* NFSV4.0プロトコルを明確にします。

1.5. NFSv4 Goals
1.5. NFSV4目標

The NFSv4 protocol is a further revision of the NFS protocol defined already by NFSv3 [38]. It retains the essential characteristics of previous versions: easy recovery; independence of transport protocols, operating systems, and file systems; simplicity; and good performance. NFSv4 has the following goals:

NFSV4プロトコルは、NFSV3 [38]で既に定義されているNFSプロトコルのさらなるリビジョンです。それは以前のバージョンの本質的な特徴を保持します:簡単な回復。トランスポートプロトコル、オペレーティングシステム、およびファイルシステムの独立性。シンプルさ。そして良いパフォーマンス。NFSV4には次の目標があります。

* Improved access and good performance on the Internet

* インターネット上のアクセスと良好なパフォーマンスが向上しました

The protocol is designed to transit firewalls easily, perform well where latency is high and bandwidth is low, and scale to very large numbers of clients per server.


* Strong security with negotiation built into the protocol

* 議定書に組み込まれた交渉による強力なセキュリティ

The protocol builds on the work of the ONCRPC working group in supporting the RPCSEC_GSS protocol. Additionally, the NFSv4.1 protocol provides a mechanism to allow clients and servers the ability to negotiate security and require clients and servers to support a minimal set of security schemes.


* Good cross-platform interoperability

* 良いクロスプラットフォームの相互運用性

The protocol features a file system model that provides a useful, common set of features that does not unduly favor one file system or operating system over another.


* Designed for protocol extensions

* プロトコル拡張用に設計されています

The protocol is designed to accept standard extensions within a framework that enables and encourages backward compatibility.


1.6. NFSv4.1 Goals
1.6. NFSV4.1目標

NFSv4.1 has the following goals, within the framework established by the overall NFSv4 goals.


* To correct significant structural weaknesses and oversights discovered in the base protocol.

* 基本プロトコルで発見されたかなりの構造的弱点と監視を修正するため。

* To add clarity and specificity to areas left unaddressed or not addressed in sufficient detail in the base protocol. However, as stated in Section 1.4, it is not a goal to clarify the NFSv4.0 protocol in the NFSv4.1 specification.

* ベースプロトコルでは十分な詳細で埋め込まれていないか、または対処されていない領域に明確さと特異性を追加する。ただし、セクション1.4に記載されているように、NFSV4.1仕様でNFSV4.0プロトコルを明確にすることは目標ではありません。

* To add specific features based on experience with the existing protocol and recent industry developments.

* 既存のプロトコルと最近の業界の開発の経験に基づいて特定の機能を追加する。

* To provide protocol support to take advantage of clustered server deployments including the ability to provide scalable parallel access to files distributed among multiple servers.

* プロトコルサポートを提供するには、複数のサーバー間で分散されたファイルへのスケーラブルな並列アクセスを提供する機能を含む、クラスタ化されたサーバーの展開を提供すること。

1.7. General Definitions
1.7. 一般的な定義

The following definitions provide an appropriate context for the reader.


Byte: In this document, a byte is an octet, i.e., a datum exactly 8 bits in length.


Client: The client is the entity that accesses the NFS server's resources. The client may be an application that contains the logic to access the NFS server directly. The client may also be the traditional operating system client that provides remote file system services for a set of applications.


A client is uniquely identified by a client owner.


With reference to byte-range locking, the client is also the entity that maintains a set of locks on behalf of one or more applications. This client is responsible for crash or failure recovery for those locks it manages.


Note that multiple clients may share the same transport and connection and multiple clients may exist on the same network node.


Client ID: The client ID is a 64-bit quantity used as a unique, short-hand reference to a client-supplied verifier and client owner. The server is responsible for supplying the client ID.


Client Owner: The client owner is a unique string, opaque to the server, that identifies a client. Multiple network connections and source network addresses originating from those connections may share a client owner. The server is expected to treat requests from connections with the same client owner as coming from the same client.


File System: The file system is the collection of objects on a server (as identified by the major identifier of a server owner, which is defined later in this section) that share the same fsid attribute (see Section


Lease: A lease is an interval of time defined by the server for which the client is irrevocably granted locks. At the end of a lease period, locks may be revoked if the lease has not been extended. A lock must be revoked if a conflicting lock has been granted after the lease interval.


A server grants a client a single lease for all state.


Lock: The term "lock" is used to refer to byte-range (in UNIX environments, also known as record) locks, share reservations, delegations, or layouts unless specifically stated otherwise.


Secret State Verifier (SSV): The SSV is a unique secret key shared between a client and server. The SSV serves as the secret key for an internal (that is, internal to NFSv4.1) Generic Security Services (GSS) mechanism (the SSV GSS mechanism; see Section 2.10.9). The SSV GSS mechanism uses the SSV to compute message integrity code (MIC) and Wrap tokens. See Section for more details on how NFSv4.1 uses the SSV and the SSV GSS mechanism.

Secret State Verifier(SSV):SSVはクライアントとサーバー間で共有されている一意の秘密鍵です。SSVは、内部(つまり、NFSV4.1の内部にある)Generic Security Services(GSS)メカニズム(SSV GSSメカニズム)の秘密鍵として機能します(SSV GSSメカニズム; 2.10.9を参照)。SSV GSSメカニズムはSSVを使用してメッセージ整合性コード(MIC)とラップトークンを計算します。NFSv4.1のSSVとSSV GSSメカニズムの使用方法の詳細については、項を参照してください。

Server: The Server is the entity responsible for coordinating client access to a set of file systems and is identified by a server owner. A server can span multiple network addresses.


Server Owner: The server owner identifies the server to the client. The server owner consists of a major identifier and a minor identifier. When the client has two connections each to a peer with the same major identifier, the client assumes that both peers are the same server (the server namespace is the same via each connection) and that lock state is shareable across both connections. When each peer has both the same major and minor identifiers, the client assumes that each connection might be associable with the same session.


Stable Storage: Stable storage is storage from which data stored by an NFSv4.1 server can be recovered without data loss from multiple power failures (including cascading power failures, that is, several power failures in quick succession), operating system failures, and/or hardware failure of components other than the storage medium itself (such as disk, nonvolatile RAM, flash memory, etc.).

安定したストレージ:安定したストレージは、複数の電源障害(カスケード能力の障害、すなわち迅速な累進のいくつかの電力障害を含む)、オペレーティングシステムの障害、および/ /記憶媒体自体(ディスク、不揮発性RAM、フラッシュメモリなど)以外のコンポーネントのハードウェア障害。

Some examples of stable storage that are allowable for an NFS server include:


1. Media commit of data; that is, the modified data has been successfully written to the disk media, for example, the disk platter.

1. データのメディアコミット。すなわち、修正されたデータは、ディスク媒体、例えばディスクプラッタに正常に書き込まれてきた。

2. An immediate reply disk drive with battery-backed, on-drive intermediate storage or uninterruptible power system (UPS).

2. バッテリバックドドライブ中間ストレージまたは無停電電力システム(UPS)を備えた即時返信ディスクドライブ。

3. Server commit of data with battery-backed intermediate storage and recovery software.

3. バッテリバックアップ中間記憶域および回復ソフトウェアを持つデータのサーバー。

4. Cache commit with uninterruptible power system (UPS) and recovery software.

4. 無停電電源システム(UPS)および回復ソフトウェアを使用してキャッシュをコミットします。

Stateid: A stateid is a 128-bit quantity returned by a server that uniquely defines the open and locking states provided by the server for a specific open-owner or lock-owner/open-owner pair for a specific file and type of lock.


Verifier: A verifier is a 64-bit quantity generated by the client that the server can use to determine if the client has restarted and lost all previous lock state.


1.8. Overview of NFSv4.1 Features
1.8. NFSV4.1機能の概要

The major features of the NFSv4.1 protocol will be reviewed in brief. This will be done to provide an appropriate context for both the reader who is familiar with the previous versions of the NFS protocol and the reader who is new to the NFS protocols. For the reader new to the NFS protocols, there is still a set of fundamental knowledge that is expected. The reader should be familiar with the External Data Representation (XDR) and Remote Procedure Call (RPC) protocols as described in [2] and [3]. A basic knowledge of file systems and distributed file systems is expected as well.


In general, this specification of NFSv4.1 will not distinguish those features added in minor version 1 from those present in the base protocol but will treat NFSv4.1 as a unified whole. See Section 1.9 for a summary of the differences between NFSv4.0 and NFSv4.1.


1.8.1. RPC and Security
1.8.1. RPCとセキュリティ

As with previous versions of NFS, the External Data Representation (XDR) and Remote Procedure Call (RPC) mechanisms used for the NFSv4.1 protocol are those defined in [2] and [3]. To meet end-to-end security requirements, the RPCSEC_GSS framework [4] is used to extend the basic RPC security. With the use of RPCSEC_GSS, various mechanisms can be provided to offer authentication, integrity, and privacy to the NFSv4 protocol. Kerberos V5 is used as described in [5] to provide one security framework. With the use of RPCSEC_GSS, other mechanisms may also be specified and used for NFSv4.1 security.

以前のバージョンのNFSと同様に、NFSv4.1プロトコルに使用される外部データ表現(XDR)およびリモートプロシージャコール(RPC)メカニズムは、[2]と[3]で定義されているものです。エンドツーエンドのセキュリティ要件を満たすために、RPCSEC_GSSフレームワーク[4]は基本的なRPCセキュリティを拡張するために使用されます。RPCSEC_GSSを使用すると、NFSV4プロトコルに対する認証、整合性、およびプライバシーを提供するためにさまざまなメカニズムを提供できます。Kerberos V5は[5]で説明されているように使用して、1つのセキュリティフレームワークを提供します。RPCSEC_GSSを使用すると、他のメカニズムも指定し、NFSV4.1セキュリティに使用することができます。

To enable in-band security negotiation, the NFSv4.1 protocol has operations that provide the client a method of querying the server about its policies regarding which security mechanisms must be used for access to the server's file system resources. With this, the client can securely match the security mechanism that meets the policies specified at both the client and server.


NFSv4.1 introduces parallel access (see Section, which is called pNFS. The security framework described in this section is significantly modified by the introduction of pNFS (see Section 12.9), because data access is sometimes not over RPC. The level of significance varies with the storage protocol (see Section 12.2.5) and can be as low as zero impact (see Section 13.12).


1.8.2. Protocol Structure
1.8.2. プロトコル構造 Core Protocol コアプロトコル

Unlike NFSv3, which used a series of ancillary protocols (e.g., NLM, NSM (Network Status Monitor), MOUNT), within all minor versions of NFSv4 a single RPC protocol is used to make requests to the server. Facilities that had been separate protocols, such as locking, are now integrated within a single unified protocol.

NFSv3の一連の補助プロトコル(例えば、NLM、NSM(ネットワークステータスモニタ)、マウント)を使用したNFSV3とは異なり、NFSV4のすべてのマイナーバージョン内で、サーバーへの要求を行うために使用されます。ロックなどの別々のプロトコルであった機能は、単一の統合プロトコル内に統合されています。 Parallel Access 並行アクセス

Minor version 1 supports high-performance data access to a clustered server implementation by enabling a separation of metadata access and data access, with the latter done to multiple servers in parallel.


Such parallel data access is controlled by recallable objects known as "layouts", which are integrated into the protocol locking model. Clients direct requests for data access to a set of data servers specified by the layout via a data storage protocol which may be NFSv4.1 or may be another protocol.


Because the protocols used for parallel data access are not necessarily RPC-based, the RPC-based security model (Section 1.8.1) is obviously impacted (see Section 12.9). The degree of impact varies with the storage protocol (see Section 12.2.5) used for data access, and can be as low as zero (see Section 13.12).


1.8.3. File System Model
1.8.3. ファイルシステムモデル

The general file system model used for the NFSv4.1 protocol is the same as previous versions. The server file system is hierarchical with the regular files contained within being treated as opaque byte streams. In a slight departure, file and directory names are encoded with UTF-8 to deal with the basics of internationalization.


The NFSv4.1 protocol does not require a separate protocol to provide for the initial mapping between path name and filehandle. All file systems exported by a server are presented as a tree so that all file systems are reachable from a special per-server global root filehandle. This allows LOOKUP operations to be used to perform functions previously provided by the MOUNT protocol. The server provides any necessary pseudo file systems to bridge any gaps that arise due to unexported gaps between exported file systems.

NFSV4.1プロトコルは、パス名とFileHandleの間の初期マッピングを提供するための別のプロトコルを必要としません。サーバーによってエクスポートされたすべてのファイルシステムはすべてのファイルシステムが特別なサーバーごとのグローバルルートファイルハンドルから到達可能になるようにツリーとして表示されます。これにより、ルックアップ操作を使用して、マウントプロトコルによって以前に提供された機能を実行できます。サーバーは、エクスポートされたファイルシステム間のエクスポートされていないギャップが原因で発生するギャップを埋めるために必要な疑似ファイルシステムを提供します。 Filehandles ファイルハンドル

As in previous versions of the NFS protocol, opaque filehandles are used to identify individual files and directories. Lookup-type and create operations translate file and directory names to filehandles, which are then used to identify objects in subsequent operations.


The NFSv4.1 protocol provides support for persistent filehandles, guaranteed to be valid for the lifetime of the file system object designated. In addition, it provides support to servers to provide filehandles with more limited validity guarantees, called volatile filehandles.

NFSV4.1プロトコルは、永続的なファイルハンドルをサポートし、指定されたファイルシステムオブジェクトの有効期間に有効であることが保証されています。さらに、揮発性のファイルハンドルと呼ばれる、より限定された有効性保証付きのファイルハンドルを提供するためのサーバーへのサポートを提供します。 File Attributes ファイル属性

The NFSv4.1 protocol has a rich and extensible file object attribute structure, which is divided into REQUIRED, RECOMMENDED, and named attributes (see Section 5).


Several (but not all) of the REQUIRED attributes are derived from the attributes of NFSv3 (see the definition of the fattr3 data type in [38]). An example of a REQUIRED attribute is the file object's type (Section so that regular files can be distinguished from directories (also known as folders in some operating environments) and other types of objects. REQUIRED attributes are discussed in Section 5.1.

必要な属性のいくつか(まだ全体ではない)は、NFSV3の属性から派生しています([38]のFATTR 3データ型の定義を参照)。必要な属性の例は、ファイルオブジェクトのタイプ(セクション5.8.1.2)で、通常のファイルはディレクトリ(一部のオペレーティング環境でもフォルダとも呼ばれる)やその他の種類のオブジェクトとは区別できます。必須属性についてはセクション5.1で説明します。

An example of three RECOMMENDED attributes are acl, sacl, and dacl. These attributes define an Access Control List (ACL) on a file object (Section 6). An ACL provides directory and file access control beyond the model used in NFSv3. The ACL definition allows for specification of specific sets of permissions for individual users and groups. In addition, ACL inheritance allows propagation of access permissions and restrictions down a directory tree as file system objects are created. RECOMMENDED attributes are discussed in Section 5.2.


A named attribute is an opaque byte stream that is associated with a directory or file and referred to by a string name. Named attributes are meant to be used by client applications as a method to associate application-specific data with a regular file or directory. NFSv4.1 modifies named attributes relative to NFSv4.0 by tightening the allowed operations in order to prevent the development of non-interoperable implementations. Named attributes are discussed in Section 5.3.

名前付き属性は、ディレクトリまたはファイルに関連付けられ、文字列名によって参照される不透明バイトストリームです。名前付き属性は、アプリケーション固有のデータを通常のファイルまたはディレクトリと関連付ける方法として、クライアントアプリケーションによって使用されることを目的としています。NFSV4.1は、非相互運用可能な実装の開発を防ぐために、許可された操作を締め付けることによって、NFSV4.0に対する名前付き属性を変更します。名前付き属性はセクション5.3で説明されています。 Multi-Server Namespace マルチサーバーネームスペース

NFSv4.1 contains a number of features to allow implementation of namespaces that cross server boundaries and that allow and facilitate a nondisruptive transfer of support for individual file systems between servers. They are all based upon attributes that allow one file system to specify alternate, additional, and new location information that specifies how the client may access that file system.


These attributes can be used to provide for individual active file systems:


* Alternate network addresses to access the current file system instance.

* 現在のファイルシステムインスタンスにアクセスするための代替ネットワークアドレス。

* The locations of alternate file system instances or replicas to be used in the event that the current file system instance becomes unavailable.

* 現在のファイルシステムインスタンスが利用できなくなった場合に使用される代替ファイルシステムインスタンスまたはレプリカの場所。

These file system location attributes may be used together with the concept of absent file systems, in which a position in the server namespace is associated with locations on other servers without there being any corresponding file system instance on the current server. For example,


* These attributes may be used with absent file systems to implement referrals whereby one server may direct the client to a file system provided by another server. This allows extensive multi-server namespaces to be constructed.

* これらの属性は、1つのサーバが他のサーバによって提供されたファイルシステムに指示することができる参照を実装するために、存在しないファイルシステムと共に使用され得る。これにより、広範なマルチサーバーネームスペースを構築できます。

* These attributes may be provided when a previously present file system becomes absent. This allows nondisruptive migration of file systems to alternate servers.

* これらの属性は、以前に現在のファイルシステムが存在しない場合に提供されてもよい。これにより、ファイルシステムの交互のサーバーへの中断の中断が可能になります。

1.8.4. Locking Facilities
1.8.4. ロック設備

As mentioned previously, NFSv4.1 is a single protocol that includes locking facilities. These locking facilities include support for many types of locks including a number of sorts of recallable locks. Recallable locks such as delegations allow the client to be assured that certain events will not occur so long as that lock is held. When circumstances change, the lock is recalled via a callback request. The assurances provided by delegations allow more extensive caching to be done safely when circumstances allow it.


The types of locks are:


* Share reservations as established by OPEN operations.

* オープン操作によって確立されたように予約を共有する。

* Byte-range locks.

* バイトレンジロック

* File delegations, which are recallable locks that assure the holder that inconsistent opens and file changes cannot occur so long as the delegation is held.

* 委任が保持されている限り、矛盾するホルダーを保証するリコール可能なロックであるリソタリングロックです。

* Directory delegations, which are recallable locks that assure the holder that inconsistent directory modifications cannot occur so long as the delegation is held.

* ディレクトリの委任は、委任が保持されている限り、矛盾するディレクトリ変更が発生することができないホルダーを保証するリソタリングロックです。

* Layouts, which are recallable objects that assure the holder that direct access to the file data may be performed directly by the client and that no change to the data's location that is inconsistent with that access may be made so long as the layout is held.

* ファイルデータへのアクセスを確実にするホルダを保証するレイアウトは、クライアントによって直接実行され、そのアクセスと矛盾しないデータの位置に変更されないことが、レイアウトが保持されている限り、データの位置に変更されない可能性がある。

All locks for a given client are tied together under a single client-wide lease. All requests made on sessions associated with the client renew that lease. When the client's lease is not promptly renewed, the client's locks are subject to revocation. In the event of server restart, clients have the opportunity to safely reclaim their locks within a special grace period.


1.9. Differences from NFSv4.0
1.9. NFSv4.0との違い

The following summarizes the major differences between minor version 1 and the base protocol:


* Implementation of the sessions model (Section 2.10).

* セッションモデルの実装(セクション2.10)

* Parallel access to data (Section 12).

* データへの並列アクセス(セクション12)。

* Addition of the RECLAIM_COMPLETE operation to better structure the lock reclamation process (Section 18.51).

* ロック再生プロセスをよりよく構成するためのRECLAIM_COMPLETE操作の追加(セクション18.51)。

* Enhanced delegation support as follows.

* 以下のような強化された委任サポート。

- Delegations on directories and other file types in addition to regular files (Section 18.39, Section 18.49).

- 通常のファイルに加えて、ディレクトリやその他のファイルタイプに関する代理人(18.39項18.49節)。

- Operations to optimize acquisition of recalled or denied delegations (Section 18.49, Section 20.5, Section 20.7).

- リコールまたは拒否された委任の取得を最適化するための操作(第18.49節、セクション20.5、セクション20.7)。

- Notifications of changes to files and directories (Section 18.39, Section 20.4).

- ファイルとディレクトリへの変更の通知(セクション18.39,20.4)。

- A method to allow a server to indicate that it is recalling one or more delegations for resource management reasons, and thus a method to allow the client to pick which delegations to return (Section 20.6).

- サーバーが、リソース管理上の理由から1つ以上の委任を呼び出すことを示す方法、したがって、クライアントがどの委任を返すかをユーザーに返す方法を許可する方法です(セクション20.6)。

* Attributes can be set atomically during exclusive file create via the OPEN operation (see the new EXCLUSIVE4_1 creation method in Section 18.16).

* 属性は、オープン操作を介して排他ファイル作成中にアトミックに設定できます(セクション18.16の新しいexclusive4_1の作成方法を参照)。

* Open files can be preserved if removed and the hard link count ("hard link" is defined in an Open Group [Section 3.191 of Chapter 3 of Base Definitions of The Open Group Base Specifications Issue 6 IEEE Std 1003.1, 2004 Edition, HTML Version"">6] standard) goes to zero, thus obviating the need for clients to rename deleted files to partially hidden names -- colloquially called "silly rename" (see the new OPEN4_RESULT_PRESERVE_UNLINKED reply flag in Section 18.16).

* 削除された場合はオープンファイルを保存でき、ハードリンク数(「ハードリンク」をオープングループのセクション3のセクション3のセクション3.191号のセクション3.191号:IEEE STD 1003.1,2004版、HTML版)"6]標準)はゼロになり、削除されたファイルの名前を部分的に隠された名前に名前を変更する必要がなくなります。

* Improved compatibility with Microsoft Windows for Access Control Lists (Section 6.2.3, Section 6.2.2, Section

* アクセス制御リストのMicrosoft Windowsとの互換性の向上(6.2.3項6.2.2項6.4.3.2項)。

* Data retention (Section 5.13).

* データ保持(セクション5.13)。

* Identification of the implementation of the NFS client and server (Section 18.35).

* NFSクライアントとサーバーの実装の識別(セクション18.35)。

* Support for notification of the availability of byte-range locks (see the new OPEN4_RESULT_MAY_NOTIFY_LOCK reply flag in Section 18.16 and see Section 20.11).

* バイトレンジロックの可用性の通知をサポートします(セクション18.16の新しいOpen4_Result_May_Notify_lockの返信フラグを参照)。

* In NFSv4.1, LIPKEY and SPKM-3 are not required security mechanisms [39].

* NFSV4.1では、リッキーとSPKM-3は必須のセキュリティメカニズムではありません[39]。

2. Core Infrastructure
2. コアインフラストラクチャー
2.1. Introduction
2.1. はじめに

NFSv4.1 relies on core infrastructure common to nearly every operation. This core infrastructure is described in the remainder of this section.


2.2. RPC and XDR
2.2. RPCとXDR

The NFSv4.1 protocol is a Remote Procedure Call (RPC) application that uses RPC version 2 and the corresponding eXternal Data Representation (XDR) as defined in [3] and [2].


2.2.1. RPC-Based Security
2.2.1. RPCベースのセキュリティ

Previous NFS versions have been thought of as having a host-based authentication model, where the NFS server authenticates the NFS client, and trusts the client to authenticate all users. Actually, NFS has always depended on RPC for authentication. One of the first forms of RPC authentication, AUTH_SYS, had no strong authentication and required a host-based authentication approach. NFSv4.1 also depends on RPC for basic security services and mandates RPC support for a user-based authentication model. The user-based authentication model has user principals authenticated by a server, and in turn the server authenticated by user principals. RPC provides some basic security services that are used by NFSv4.1.

以前のNFSバージョンは、NFSサーバーがNFSクライアントを認証し、すべてのユーザーを認証するようにクライアントに信頼するというホストベースの認証モデルを持つと考えられています。実際には、NFSは常に認証のためにRPCに依存しています。RPC認証auth_sysの最初の形式の1つは、強力な認証を有し、ホストベースの認証アプローチを必要としました。NFSV4.1は、基本的なセキュリティサービスのためのRPCにも依存し、ユーザーベースの認証モデルのRPCサポートを義務付けます。ユーザーベースの認証モデルには、サーバーによって認証されているユーザープリンシパルがあり、ユーザーのプリンシパルによって認証されたサーバーがあります。RPCは、NFSv4.1によって使用される基本的なセキュリティサービスをいくつか提供します。 RPC Security Flavors RPCセキュリティフレーバー

As described in "Authentication", Section 7 of [3], RPC security is encapsulated in the RPC header, via a security or authentication flavor, and information specific to the specified security flavor. Every RPC header conveys information used to identify and authenticate a client and server. As discussed in Section, some security flavors provide additional security services.


NFSv4.1 clients and servers MUST implement RPCSEC_GSS. (This requirement to implement is not a requirement to use.) Other flavors, such as AUTH_NONE and AUTH_SYS, MAY be implemented as well.

NFSV4.1クライアントとサーバーはRPCSEC_GSSを実装する必要があります。(実装するこの要件は使用の要件ではありません。)auth_noneやauth_sysなどの他のフレーバーも同様に実装されてもよい。 RPCSEC_GSS and Security Services RPCSEC_GSSおよびセキュリティサービス

RPCSEC_GSS [4] uses the functionality of GSS-API [7]. This allows for the use of various security mechanisms by the RPC layer without the additional implementation overhead of adding RPC security flavors.

RPCSEC_GSS [4]はGSS-API [7]の機能を使用します。これにより、RPCセキュリティフレーバーを追加するための追加の実装のオーバーヘッドなしに、RPCレイヤによって様々なセキュリティメカニズムを使用することができます。 Identification, Authentication, Integrity, Privacy 識別、認証、整合性、プライバシー

Via the GSS-API, RPCSEC_GSS can be used to identify and authenticate users on clients to servers, and servers to users. It can also perform integrity checking on the entire RPC message, including the RPC header, and on the arguments or results. Finally, privacy, usually via encryption, is a service available with RPCSEC_GSS. Privacy is performed on the arguments and results. Note that if privacy is selected, integrity, authentication, and identification are enabled. If privacy is not selected, but integrity is selected, authentication and identification are enabled. If integrity and privacy are not selected, but authentication is enabled, identification is enabled. RPCSEC_GSS does not provide identification as a separate service.


Although GSS-API has an authentication service distinct from its privacy and integrity services, GSS-API's authentication service is not used for RPCSEC_GSS's authentication service. Instead, each RPC request and response header is integrity protected with the GSS-API integrity service, and this allows RPCSEC_GSS to offer per-RPC authentication and identity. See [4] for more information.

GSS-APIにはプライバシーサービスとIntegrity Servicesとは異なる認証サービスがありますが、GSS-APIの認証サービスはRPCSEC_GSSの認証サービスには使用されません。代わりに、各RPC要求および応答ヘッダーはGSS-API Integrityサービスで保護されている整合性であり、これによりRPCSEC_GSSはRPCごとの認証とIDを提供できます。詳細については[4]を参照してください。

NFSv4.1 client and servers MUST support RPCSEC_GSS's integrity and authentication service. NFSv4.1 servers MUST support RPCSEC_GSS's privacy service. NFSv4.1 clients SHOULD support RPCSEC_GSS's privacy service.

NFSV4.1クライアントとサーバーは、RPCSEC_GSSの整合性と認証サービスをサポートしている必要があります。NFSV4.1サーバーはRPCSEC_GSSのプライバシーサービスをサポートしている必要があります。NFSV4.1クライアントはRPCSEC_GSSのプライバシーサービスをサポートする必要があります。 Security Mechanisms for NFSv4.1 NFSV4.1のセキュリティメカニズム

RPCSEC_GSS, via GSS-API, normalizes access to mechanisms that provide security services. Therefore, NFSv4.1 clients and servers MUST support the Kerberos V5 security mechanism.

RPCSEC_GSSは、GSS-APIを介して、セキュリティサービスを提供するメカニズムへのアクセスを正規化します。したがって、NFSV4.1クライアントとサーバーはKerberos V5セキュリティメカニズムをサポートしている必要があります。

The use of RPCSEC_GSS requires selection of mechanism, quality of protection (QOP), and service (authentication, integrity, privacy). For the mandated security mechanisms, NFSv4.1 specifies that a QOP of zero is used, leaving it up to the mechanism or the mechanism's configuration to map QOP zero to an appropriate level of protection. Each mandated mechanism specifies a minimum set of cryptographic algorithms for implementing integrity and privacy. NFSv4.1 clients and servers MUST be implemented on operating environments that comply with the REQUIRED cryptographic algorithms of each REQUIRED mechanism.

RPCSEC_GSSの使用には、メカニズム、保護品質(QOP)、およびサービス(認証、整合性、プライバシー)の選択が必要です。必須のセキュリティメカニズムの場合、NFSV4.1は、ゼロのQoPが使用され、メカニズムまたはメカニズムの構成に、QOPゼロを適切なレベルの保護にマッピングすることを指定します。各命令メカニズムは、整合性とプライバシーを実装するための最小の暗号化アルゴリズムのセットを指定します。NFSV4.1クライアントとサーバーは、必要な各メカニズムの必要な暗号化アルゴリズムに準拠したオペレーティング環境で実装する必要があります。 Kerberos V5 Kerberos V5

The Kerberos V5 GSS-API mechanism as described in [5] MUST be implemented with the RPCSEC_GSS services as specified in the following table:

[5]に記載されているKerberos V5 GSS-APIメカニズムは、次の表にあるRPCSEC_GSSサービスを使用して実装する必要があります。

      column descriptions:
      1 == number of pseudo flavor
      2 == name of pseudo flavor
      3 == mechanism's OID
      4 == RPCSEC_GSS service
      5 == NFSv4.1 clients MUST support
      6 == NFSv4.1 servers MUST support
      1      2        3                    4                     5   6
      390003 krb5     1.2.840.113554.1.2.2 rpc_gss_svc_none      yes yes
      390004 krb5i    1.2.840.113554.1.2.2 rpc_gss_svc_integrity yes yes
      390005 krb5p    1.2.840.113554.1.2.2 rpc_gss_svc_privacy    no yes

Note that the number and name of the pseudo flavor are presented here as a mapping aid to the implementor. Because the NFSv4.1 protocol includes a method to negotiate security and it understands the GSS-API mechanism, the pseudo flavor is not needed. The pseudo flavor is needed for the NFSv3 since the security negotiation is done via the MOUNT protocol as described in [40].


At the time NFSv4.1 was specified, the Advanced Encryption Standard (AES) with HMAC-SHA1 was a REQUIRED algorithm set for Kerberos V5. In contrast, when NFSv4.0 was specified, weaker algorithm sets were REQUIRED for Kerberos V5, and were REQUIRED in the NFSv4.0 specification, because the Kerberos V5 specification at the time did not specify stronger algorithms. The NFSv4.1 specification does not specify REQUIRED algorithms for Kerberos V5, and instead, the implementor is expected to track the evolution of the Kerberos V5 standard if and when stronger algorithms are specified.

NFSV4.1が指定された時点で、HMAC-SHA1を持つ高度な暗号化規格(AES)はKerberos V5に設定された要求アルゴリズムでした。対照的に、NFSV4.0が指定されている場合、Kerberos V5に弱いアルゴリズムセットが必要であり、NFSV4.0仕様では必要とされていました。なぜなら、Kerberos V5仕様はより強いアルゴリズムを指定しなかったためです。NFSV4.1仕様はKerberos V5に必要なアルゴリズムを指定しておらず、代わりに、実装者は、より強いアルゴリズムが指定されている場合、Kerberos V5規格の進化を追跡することが予想されます。 Security Considerations for Cryptographic Algorithms in Kerberos V5 Kerberos v5における暗号化アルゴリズムに関するセキュリティ上の考慮事項

When deploying NFSv4.1, the strength of the security achieved depends on the existing Kerberos V5 infrastructure. The algorithms of Kerberos V5 are not directly exposed to or selectable by the client or server, so there is some due diligence required by the user of NFSv4.1 to ensure that security is acceptable where needed.

NFSV4.1を展開するとき、達成されたセキュリティの強さは既存のKerberos v5インフラストラクチャによって異なります。Kerberos v5のアルゴリズムは、クライアントまたはサーバーによって直接公開されていないため、必要に応じてセキュリティが許容できるようにするためにNFSV4.1のユーザーが必要とするデューデリジェンスがいくつかあります。 GSS Server Principal GSSサーバープリンシパル

Regardless of what security mechanism under RPCSEC_GSS is being used, the NFS server MUST identify itself in GSS-API via a GSS_C_NT_HOSTBASED_SERVICE name type. GSS_C_NT_HOSTBASED_SERVICE names are of the form:

RPCSEC_GSSの下のセキュリティメカニズムが使用されているのかにかかわらず、NFSサーバーはGSS_C_NT_HOSTBASED_SERVICE NAMEタイプを介してGSS-APIで自分自身を識別する必要があります。GSS_C_NT_HOSTBASED_SERVICE名は次の形式です。



For NFS, the "service" element is




Implementations of security mechanisms will convert nfs@hostname to various different forms. For Kerberos V5, the following form is RECOMMENDED:

セキュリティメカニズムの実装は、NFS @ hostnameをさまざまな形式に変換します。Kerberos V5の場合、次のフォームをお勧めします。


NFS /ホスト名

2.3. 化合物とcb_compound.

A significant departure from the versions of the NFS protocol before NFSv4 is the introduction of the COMPOUND procedure. For the NFSv4 protocol, in all minor versions, there are exactly two RPC procedures, NULL and COMPOUND. The COMPOUND procedure is defined as a series of individual operations and these operations perform the sorts of functions performed by traditional NFS procedures.


The operations combined within a COMPOUND request are evaluated in order by the server, without any atomicity guarantees. A limited set of facilities exist to pass results from one operation to another. Once an operation returns a failing result, the evaluation ends and the results of all evaluated operations are returned to the client.


With the use of the COMPOUND procedure, the client is able to build simple or complex requests. These COMPOUND requests allow for a reduction in the number of RPCs needed for logical file system operations. For example, multi-component look up requests can be constructed by combining multiple LOOKUP operations. Those can be further combined with operations such as GETATTR, READDIR, or OPEN plus READ to do more complicated sets of operation without incurring additional latency.

複合手順を使用すると、クライアントは単純または複雑な要求を作成することができます。これらの複合要求により、論理ファイルシステムの操作に必要なRPCの数を減らすことができます。たとえば、複数のルックアップ操作を組み合わせることで、マルチコンポーネントルックアップ要求を構築できます。追加の待ち時間を招くことなく、getAttr、ReadDir、またはOpen Plusの読み取りなどの操作とさらに組み合わせることができます。

NFSv4.1 also contains a considerable set of callback operations in which the server makes an RPC directed at the client. Callback RPCs have a similar structure to that of the normal server requests. In all minor versions of the NFSv4 protocol, there are two callback RPC procedures: CB_NULL and CB_COMPOUND. The CB_COMPOUND procedure is defined in an analogous fashion to that of COMPOUND with its own set of callback operations.

NFSV4.1には、サーバーがクライアントにRPCを向けたかのかなりのコールバック操作のセットも含まれています。コールバックRPCは、通常のサーバ要求と同様の構造を持ちます。NFSV4プロトコルのすべてのマイナーバージョンでは、CB_NULLとCB_COMPOUND 2つのコールバックRPCプロシージャがあります。CB_COMPOUND手順は、独自のコールバック操作を持つ化合物のそれと同様の方法で定義されています。

The addition of new server and callback operations within the COMPOUND and CB_COMPOUND request framework provides a means of extending the protocol in subsequent minor versions.

複合およびCB_Compound Request Framework内の新しいサーバーおよびコールバック操作の追加は、その後のマイナーバージョンでプロトコルを拡張する手段を提供します。

Except for a small number of operations needed for session creation, server requests and callback requests are performed within the context of a session. Sessions provide a client context for every request and support robust replay protection for non-idempotent requests.


2.4. Client Identifiers and Client Owners
2.4. クライアント識別子とクライアントの所有者

For each operation that obtains or depends on locking state, the specific client needs to be identifiable by the server.


Each distinct client instance is represented by a client ID. A client ID is a 64-bit identifier representing a specific client at a given time. The client ID is changed whenever the client re-initializes, and may change when the server re-initializes. Client IDs are used to support lock identification and crash recovery.


During steady state operation, the client ID associated with each operation is derived from the session (see Section 2.10) on which the operation is sent. A session is associated with a client ID when the session is created.


Unlike NFSv4.0, the only NFSv4.1 operations possible before a client ID is established are those needed to establish the client ID.


A sequence of an EXCHANGE_ID operation followed by a CREATE_SESSION operation using that client ID (eir_clientid as returned from EXCHANGE_ID) is required to establish and confirm the client ID on the server. Establishment of identification by a new incarnation of the client also has the effect of immediately releasing any locking state that a previous incarnation of that same client might have had on the server. Such released state would include all byte-range lock, share reservation, layout state, and -- where the server supports neither the CLAIM_DELEGATE_PREV nor CLAIM_DELEG_CUR_FH claim types -- all delegation state associated with the same client with the same identity. For discussion of delegation state recovery, see Section 10.2.1. For discussion of layout state recovery, see Section 12.7.1.

Exchange_ID操作のシーケンスとそれに続くそのクライアントIDを使用したCREATE_SESSION操作(Exchange_IDから返されたEIR_ClientID)を使用して、サーバー上のクライアントIDを確立して確認するために必要です。クライアントの新しい化身による識別の確立も、以前のクライアントの以前の化身がサーバー上であった可能性があるようなロック状態を直ちに解放するという効果もあります。このようなリリース状態には、すべてのバイトレンジロック、共有予約、レイアウト状態、および - サーバがクレームのいずれかをサポートしていない場合、サーバがクレームのいずれかをサポートしていません。委任状況回復については、10.2.1項を参照してください。レイアウト状態の回復については、12.7.1項を参照してください。

Releasing such state requires that the server be able to determine that one client instance is the successor of another. Where this cannot be done, for any of a number of reasons, the locking state will remain for a time subject to lease expiration (see Section 8.3) and the new client will need to wait for such state to be removed, if it makes conflicting lock requests.


Client identification is encapsulated in the following client owner data type:


   struct client_owner4 {
           verifier4       co_verifier;
           opaque          co_ownerid<NFS4_OPAQUE_LIMIT>;

The first field, co_verifier, is a client incarnation verifier, allowing the server to distinguish successive incarnations (e.g., reboots) of the same client. The server will start the process of canceling the client's leased state if co_verifier is different than what the server has previously recorded for the identified client (as specified in the co_ownerid field).


The second field, co_ownerid, is a variable length string that uniquely defines the client so that subsequent instances of the same client bear the same co_ownerid with a different verifier.


There are several considerations for how the client generates the co_ownerid string:


* The string should be unique so that multiple clients do not present the same string. The consequences of two clients presenting the same string range from one client getting an error to one client having its leased state abruptly and unexpectedly cancelled.

* 複数のクライアントが同じ文字列を存在しないように、文字列は一意であるべきです。1つのクライアントから同じ文字列範囲を表示する2つのクライアントの結果は、そのリース状態を突然、予期せずにキャンセルされた1つのクライアントにエラーを取得します。

* The string should be selected so that subsequent incarnations (e.g., restarts) of the same client cause the client to present the same string. The implementor is cautioned from an approach that requires the string to be recorded in a local file because this precludes the use of the implementation in an environment where there is no local disk and all file access is from an NFSv4.1 server.

* 同じクライアントのその後のinnarations(たとえば、再起動)がクライアントに同じ文字列を表示させるように文字列を選択する必要があります。この実装者は、ローカルファイルに記録されるように文字列を記録するためのアプローチから、ローカルディスクがない環境での実装の使用を排除し、すべてのファイルアクセスがNFSV4.1サーバーからのものであるためです。

* The string should be the same for each server network address that the client accesses. This way, if a server has multiple interfaces, the client can trunk traffic over multiple network paths as described in Section 2.10.5. (Note: the precise opposite was advised in the NFSv4.0 specification [37].)

* クライアントがアクセスするサーバーネットワークアドレスごとに文字列は同じである必要があります。このようにして、サーバに複数のインタフェースがある場合、クライアントはセクション2.10.5で説明されているように複数のネットワークパスを介したトラフィックをトランス化できます。(注:NFSV4.0仕様では、正確な反対は推奨されています[37])

* The algorithm for generating the string should not assume that the client's network address will not change, unless the client implementation knows it is using statically assigned network addresses. This includes changes between client incarnations and even changes while the client is still running in its current incarnation. Thus, with dynamic address assignment, if the client includes just the client's network address in the co_ownerid string, there is a real risk that after the client gives up the network address, another client, using a similar algorithm for generating the co_ownerid string, would generate a conflicting co_ownerid string.

* クライアントの実装が静的に割り当てられたネットワークアドレスを使用していることを知っていない限り、文字列を生成するためのアルゴリズムは、クライアントのネットワークアドレスが変更されないと仮定しないでください。これには、クライアントのインカネルと変更さえ、クライアントが現在のインカレーションで実行されている間に変更されています。したがって、動的アドレス割り当てを使用して、クライアントがCO_OWNERID文字列内のクライアントのネットワークアドレスだけを含む場合、クライアントがCo_OwnerID文字列を生成するための同様のアルゴリズムを使用して、クライアントがネットワークアドレスをあきらめた後に実際のリスクがあります。競合するCO_OWNERID文字列を生成します。

Given the above considerations, an example of a well-generated co_ownerid string is one that includes:


* If applicable, the client's statically assigned network address.

* 該当する場合、クライアントの静的に割り当てられたネットワークアドレス。

* Additional information that tends to be unique, such as one or more of:

* 1つ以上のものなど、ユニークになる傾向がある追加情報

- The client machine's serial number (for privacy reasons, it is best to perform some one-way function on the serial number).

- クライアントマシンのシリアル番号(プライバシー上の理由から、シリアル番号に一方向機能を実行するのが最善です)。

- A Media Access Control (MAC) address (again, a one-way function should be performed).

- メディアアクセス制御(MAC)アドレス(やはり、一方向機能を実行する必要があります)。

- The timestamp of when the NFSv4.1 software was first installed on the client (though this is subject to the previously mentioned caution about using information that is stored in a file, because the file might only be accessible over NFSv4.1).

- NFSV4.1ソフトウェアが最初にクライアントにインストールされたときのタイムスタンプのタイムスタンプは(これはファイルに格納されている情報の使用について前述した注意の対象となりますが、ファイルはNFSV4.1よりもアクセスできない可能性があります)。

- A true random number. However, since this number ought to be the same between client incarnations, this shares the same problem as that of using the timestamp of the software installation.

- 真の乱数。ただし、この数はクライアントのインカネル間で同じであるべきであるため、ソフトウェアのインストールのタイムスタンプの使用方法と同じ問題を共有しています。

* For a user-level NFSv4.1 client, it should contain additional information to distinguish the client from other user-level clients running on the same host, such as a process identifier or other unique sequence.

* ユーザーレベルのNFSV4.1クライアントの場合、プロセス識別子やその他の固有のシーケンスなど、同じホスト上で実行されている他のユーザーレベルクライアントからクライアントを区別するための追加情報を含める必要があります。

The client ID is assigned by the server (the eir_clientid result from EXCHANGE_ID) and should be chosen so that it will not conflict with a client ID previously assigned by the server. This applies across server restarts.


In the event of a server restart, a client may find out that its current client ID is no longer valid when it receives an NFS4ERR_STALE_CLIENTID error. The precise circumstances depend on the characteristics of the sessions involved, specifically whether the session is persistent (see Section, but in each case the client will receive this error when it attempts to establish a new session with the existing client ID and receives the error NFS4ERR_STALE_CLIENTID, indicating that a new client ID needs to be obtained via EXCHANGE_ID and the new session established with that client ID.


When a session is not persistent, the client will find out that it needs to create a new session as a result of getting an NFS4ERR_BADSESSION, since the session in question was lost as part of a server restart. When the existing client ID is presented to a server as part of creating a session and that client ID is not recognized, as would happen after a server restart, the server will reject the request with the error NFS4ERR_STALE_CLIENTID.


In the case of the session being persistent, the client will re-establish communication using the existing session after the restart. This session will be associated with the existing client ID but may only be used to retransmit operations that the client previously transmitted and did not see replies to. Replies to operations that the server previously performed will come from the reply cache; otherwise, NFS4ERR_DEADSESSION will be returned. Hence, such a session is referred to as "dead". In this situation, in order to perform new operations, the client needs to establish a new session. If an attempt is made to establish this new session with the existing client ID, the server will reject the request with NFS4ERR_STALE_CLIENTID.


When NFS4ERR_STALE_CLIENTID is received in either of these situations, the client needs to obtain a new client ID by use of the EXCHANGE_ID operation, then use that client ID as the basis of a new session, and then proceed to any other necessary recovery for the server restart case (see Section 8.4.2).


See the descriptions of EXCHANGE_ID (Section 18.35) and CREATE_SESSION (Section 18.36) for a complete specification of these operations.


2.4.1. Upgrade from NFSv4.0 to NFSv4.1
2.4.1. NFSV4.0からNFSV4.1へのアップグレード

To facilitate upgrade from NFSv4.0 to NFSv4.1, a server may compare a value of data type client_owner4 in an EXCHANGE_ID with a value of data type nfs_client_id4 that was established using the SETCLIENTID operation of NFSv4.0. A server that does so will allow an upgraded client to avoid waiting until the lease (i.e., the lease established by the NFSv4.0 instance client) expires. This requires that the value of data type client_owner4 be constructed the same way as the value of data type nfs_client_id4. If the latter's contents included the server's network address (per the recommendations of the NFSv4.0 specification [37]), and the NFSv4.1 client does not wish to use a client ID that prevents trunking, it should send two EXCHANGE_ID operations. The first EXCHANGE_ID will have a client_owner4 equal to the nfs_client_id4. This will clear the state created by the NFSv4.0 client. The second EXCHANGE_ID will not have the server's network address. The state created for the second EXCHANGE_ID will not have to wait for lease expiration, because there will be no state to expire.

NFSV4.0からNFSV4.1へのアップグレードを容易にするために、サーバは、NFSV4.0のSetClientID操作を使用して確立されたデータ型NFS_CLIENT_ID4の値を有する、Exchange_ID内のデータ型CLIENT_OWNER4の値を比較することができる。そのため、アップグレードされたクライアントがリースまで待機しないようにする(すなわち、NFSV4.0インスタンスクライアントによって確立されたリース)が期限切れになることを可能にする。これには、データ型CLIENT_OWNER4の値がデータ型NFS_CLIENT_ID4の値と同じ方法で構成されている必要があります。後者の内容にサーバーのネットワークアドレスが含まれていた場合(NFSV4.0仕様[37]の推奨事項ごとに)、およびNFSV4.1クライアントがトランキングを防ぐクライアントIDを使用したくない場合は、2つのExchange_ID操作を送信する必要があります。最初のExchange_idは、nfs_client_id4に等しいclient_owner4を持ちます。これにより、NFSV4.0クライアントによって作成された状態がクリアされます。 2番目のExchange_IDにはサーバーのネットワークアドレスがありません。 2番目のExchange_IDのために作成された状態は、期限切れにされない状態がないため、リースの有効期限を待つ必要はありません。

2.4.2. Server Release of Client ID
2.4.2. クライアントIDのサーバーリリース

NFSv4.1 introduces a new operation called DESTROY_CLIENTID (Section 18.50), which the client SHOULD use to destroy a client ID it no longer needs. This permits graceful, bilateral release of a client ID. The operation cannot be used if there are sessions associated with the client ID, or state with an unexpired lease.


If the server determines that the client holds no associated state for its client ID (associated state includes unrevoked sessions, opens, locks, delegations, layouts, and wants), the server MAY choose to unilaterally release the client ID in order to conserve resources. If the client contacts the server after this release, the server MUST ensure that the client receives the appropriate error so that it will use the EXCHANGE_ID/CREATE_SESSION sequence to establish a new client ID. The server ought to be very hesitant to release a client ID since the resulting work on the client to recover from such an event will be the same burden as if the server had failed and restarted. Typically, a server would not release a client ID unless there had been no activity from that client for many minutes. As long as there are sessions, opens, locks, delegations, layouts, or wants, the server MUST NOT release the client ID. See Section for discussion on releasing inactive sessions.

クライアントがクライアントIDの関連状態を保持していないとサーバーが決定された場合(関連状態には取り消されていないセッション、オープン、ロック、委任、レイアウト、および欲しい)、サーバーはリソースを節約するためにクライアントIDを一方的に解放することを選択できます。このリリースの後にクライアントがサーバーに連絡している場合、サーバーはクライアントがExchange_ID / Create_Sessionシーケンスを使用して新しいクライアントIDを確立するようにする必要があることを確認する必要があります。このようなイベントから回復するクライアント上の結果として生じる作業は、サーバーが失敗して再起動した場合と同じ負担になるため、サーバーはクライアントIDを解放することが非常に躊躇します。通常、サーバーは、そのクライアントから何分間のアクティビティもない限りクライアントIDを解放しません。セッションがある限り、オープン、ロック、代表団、レイアウト、または希望は、サーバーはクライアントIDを解放してはいけません。非アクティブセッションの解放に関する議論については、セクション2.を参照してください。

2.4.3. Resolving Client Owner Conflicts
2.4.3. クライアント所有者の競合の解決

When the server gets an EXCHANGE_ID for a client owner that currently has no state, or that has state but the lease has expired, the server MUST allow the EXCHANGE_ID and confirm the new client ID if followed by the appropriate CREATE_SESSION.


When the server gets an EXCHANGE_ID for a new incarnation of a client owner that currently has an old incarnation with state and an unexpired lease, the server is allowed to dispose of the state of the previous incarnation of the client owner if one of the following is true:


* The principal that created the client ID for the client owner is the same as the principal that is sending the EXCHANGE_ID operation. Note that if the client ID was created with SP4_MACH_CRED state protection (Section 18.35), the principal MUST be based on RPCSEC_GSS authentication, the RPCSEC_GSS service used MUST be integrity or privacy, and the same GSS mechanism and principal MUST be used as that used when the client ID was created.

* クライアント所有者のクライアントIDを作成した主体は、Exchange_ID操作を送信しているプリンシパルと同じです。クライアントIDがSP4_MACH_CRED状態保護(セクション18.35)で作成された場合、プリンシパルはRPCSEC_GSS認証に基づいている必要がありますが、使用されるRPCSEC_GSSサービスは整合性またはプライバシーでなければならず、同じGSSメカニズムとプリンシパルを使用する必要があります。クライアントIDが作成されました。

* The client ID was established with SP4_SSV protection (Section 18.35, Section and the client sends the EXCHANGE_ID with the security flavor set to RPCSEC_GSS using the GSS SSV mechanism (Section 2.10.9).

* クライアントIDはSP4_SSV保護(セクション2.35,で確立され、クライアントはGSS SSVメカニズムを使用してRPCSEC_GSSにセキュリティフレーバーセットにEXCHANGE_IDを送信します(セクション2.10.9)。

* The client ID was established with SP4_SSV protection, and under the conditions described herein, the EXCHANGE_ID was sent with SP4_MACH_CRED state protection. Because the SSV might not persist across client and server restart, and because the first time a client sends EXCHANGE_ID to a server it does not have an SSV, the client MAY send the subsequent EXCHANGE_ID without an SSV RPCSEC_GSS handle. Instead, as with SP4_MACH_CRED protection, the principal MUST be based on RPCSEC_GSS authentication, the RPCSEC_GSS service used MUST be integrity or privacy, and the same GSS mechanism and principal MUST be used as that used when the client ID was created.

* クライアントIDはSP4_SSV保護を使用して確立され、本明細書に記載されている条件下で、Exchange_IDはSP4_MACH_CRED状態保護を使用して送信されました。SSVはクライアントとサーバーの再起動を継続しない可能性があるため、クライアントが初めてExchange_IDをサーバーに送信しているため、SSVがありません。クライアントはSSV RPCSEC_GSSハンドルなしで後続のExchange_idを送信できます。代わりに、SP4_MACH_CRED保護と同様に、プリンシパルはRPCSEC_GSS認証に基づいている必要があります。使用されているRPCSEC_GSSサービスは、整合性またはプライバシーでなければならず、クライアントIDが作成されたときに同じGSSメカニズムとプリンシパルを使用する必要があります。

If none of the above situations apply, the server MUST return NFS4ERR_CLID_INUSE.


If the server accepts the principal and co_ownerid as matching that which created the client ID, and the co_verifier in the EXCHANGE_ID differs from the co_verifier used when the client ID was created, then after the server receives a CREATE_SESSION that confirms the client ID, the server deletes state. If the co_verifier values are the same (e.g., the client either is updating properties of the client ID (Section 18.35) or is attempting trunking (Section 2.10.5), the server MUST NOT delete state.


2.5. Server Owners
2.5. サーバーの所有者

The server owner is similar to a client owner (Section 2.4), but unlike the client owner, there is no shorthand server ID. The server owner is defined in the following data type:


   struct server_owner4 {
    uint64_t       so_minor_id;
    opaque         so_major_id<NFS4_OPAQUE_LIMIT>;

The server owner is returned from EXCHANGE_ID. When the so_major_id fields are the same in two EXCHANGE_ID results, the connections that each EXCHANGE_ID were sent over can be assumed to address the same server (as defined in Section 1.7). If the so_minor_id fields are also the same, then not only do both connections connect to the same server, but the session can be shared across both connections. The reader is cautioned that multiple servers may deliberately or accidentally claim to have the same so_major_id or so_major_id/ so_minor_id; the reader should examine Sections 2.10.5 and 18.35 in order to avoid acting on falsely matching server owner values.

サーバーの所有者はExchange_IDから返されます。SO_MAJOR_IDフィールドが2つのExchange_IDの結果で同じである場合、各Exchange_IDが送信した接続は同じサーバーに対処すると仮定することができます(セクション1.7で定義されているように)。SO_MINOR_IDフィールドも同じである場合は、同じサーバーに接続するだけでなく、両方の接続でセッションを共有できます。リーダーには、複数のサーバーが意図的にまたは誤って同じSO_MAJOR_IDまたはSO_MAJOR_ID / SO_MINOR_IDを持つことを主張することができることに注意してください。リーダーは、誤ってサーバーの所有者の値を誤ってマッチングすることを回避するために、セクション2.10.5および18.35を調べる必要があります。

The considerations for generating an so_major_id are similar to that for generating a co_ownerid string (see Section 2.4). The consequences of two servers generating conflicting so_major_id values are less dire than they are for co_ownerid conflicts because the client can use RPCSEC_GSS to compare the authenticity of each server (see Section 2.10.5).


2.6. Security Service Negotiation
2.6. セキュリティサービスの交渉

With the NFSv4.1 server potentially offering multiple security mechanisms, the client needs a method to determine or negotiate which mechanism is to be used for its communication with the server. The NFS server may have multiple points within its file system namespace that are available for use by NFS clients. These points can be considered security policy boundaries, and, in some NFS implementations, are tied to NFS export points. In turn, the NFS server may be configured such that each of these security policy boundaries may have different or multiple security mechanisms in use.


The security negotiation between client and server SHOULD be done with a secure channel to eliminate the possibility of a third party intercepting the negotiation sequence and forcing the client and server to choose a lower level of security than required or desired. See Section 21 for further discussion.


2.6.1. NFSv4.1 Security Tuples
2.6.1. NFSV4.1セキュリティタプル

An NFS server can assign one or more "security tuples" to each security policy boundary in its namespace. Each security tuple consists of a security flavor (see Section and, if the flavor is RPCSEC_GSS, a GSS-API mechanism Object Identifier (OID), a GSS-API quality of protection, and an RPCSEC_GSS service.


2.6.2. secinfoとsecinfo_no_name.

The SECINFO and SECINFO_NO_NAME operations allow the client to determine, on a per-filehandle basis, what security tuple is to be used for server access. In general, the client will not have to use either operation except during initial communication with the server or when the client crosses security policy boundaries at the server. However, the server's policies may also change at any time and force the client to negotiate a new security tuple.


Where the use of different security tuples would affect the type of access that would be allowed if a request was sent over the same connection used for the SECINFO or SECINFO_NO_NAME operation (e.g., read-only vs. read-write) access, security tuples that allow greater access should be presented first. Where the general level of access is the same and different security flavors limit the range of principals whose privileges are recognized (e.g., allowing or disallowing root access), flavors supporting the greatest range of principals should be listed first.

さまざまなセキュリティタプルの使用が、SECINFOまたはSECINFO_NO_NAME操作(例えば、読み取り専用VS / Read-Write)アクセス、セキュリティタプルに使用されるのと同じ接続で要求が送信された場合に許可されるアクセスの種類に影響を与えるでしょう。最初に大きなアクセスを許可する必要があります。一般的なアクセスが同じであり、異なるセキュリティフレーバーが、特権が認識されているプリンシパルの範囲を制限します(例えば、rootアクセスを許可または禁止)、最大の範囲のプリンシパルをサポートするフレーバーを最初にリストする必要があります。

2.6.3. Security Error
2.6.3. セキュリティエラー

Based on the assumption that each NFSv4.1 client and server MUST support a minimum set of security (i.e., Kerberos V5 under RPCSEC_GSS), the NFS client will initiate file access to the server with one of the minimal security tuples. During communication with the server, the client may receive an NFS error of NFS4ERR_WRONGSEC. This error allows the server to notify the client that the security tuple currently being used contravenes the server's security policy. The client is then responsible for determining (see Section what security tuples are available at the server and choosing one that is appropriate for the client.

各NFSV4.1クライアントとサーバーが最小セキュリティセット(すなわちRPCSEC_GSSの下のKerberos V5)をサポートしなければならないという仮定に基づいて、NFSクライアントは最小限のセキュリティタプルのうちの1つを持つサーバーへのファイルアクセスを開始します。サーバーとの通信中、クライアントはNFS4ERR_WRONGSECのNFSエラーを受信することがあります。このエラーにより、サーバーは、現在使用されているセキュリティタプルがサーバーのセキュリティポリシーを照らしていることをクライアントに通知できます。その場合、クライアントは決定を担当します(項を参照)サーバーで利用可能なセキュリティタプルが利用可能であり、クライアントに適したものを選択するのかを選択します。 Using NFS4ERR_WRONGSEC, SECINFO, and SECINFO_NO_NAME NFS4ERR_WRONGSEC、SECINFO、およびSECINFO_NO_NAMEを使用する

This section explains the mechanics of NFSv4.1 security negotiation.

このセクションでは、NFSV4.1セキュリティ交渉の力学について説明します。 Put Filehandle Operations FileHandle Operationsを入れる

The term "put filehandle operation" refers to PUTROOTFH, PUTPUBFH, PUTFH, and RESTOREFH. Each of the subsections herein describes how the server handles a subseries of operations that starts with a put filehandle operation.

「FileHandle操作を入れる」という用語は、Putrootfh、Putpubfh、Putfh、およびRestoreFHを指します。本明細書の各サブセクションは、プットファイルハンドル操作で始まる操作のサマリーを処理する方法を説明する。 Put Filehandle Operation + SAVEFH FileHandleオペレーションSavefhを入れる

The client is saving a filehandle for a future RESTOREFH, LINK, or RENAME. SAVEFH MUST NOT return NFS4ERR_WRONGSEC. To determine whether or not the put filehandle operation returns NFS4ERR_WRONGSEC, the server implementation pretends SAVEFH is not in the series of operations and examines which of the situations described in the other subsections of Section apply.

クライアントは、将来のRestoreFH、Link、またはRenameのためにファイルハンドルを保存しています。SavefhはNFS4ERR_WRONGSECを返さないでください。PUTファイルハンドル操作がNFS4ERR_WRONGSECを返すかどうかを判断するために、サーバー実装はSAVEFHが一連の操作ではなく、セクション2.の他のサブセクションで説明されている状況のどれが適用されているかを調べます。 Two or More Put Filehandle Operations 2つ以上のファイルハンドル操作

For a series of N put filehandle operations, the server MUST NOT return NFS4ERR_WRONGSEC to the first N-1 put filehandle operations. The Nth put filehandle operation is handled as if it is the first in a subseries of operations. For example, if the server received a COMPOUND request with this series of operations -- PUTFH, PUTROOTFH, LOOKUP -- then the PUTFH operation is ignored for NFS4ERR_WRONGSEC purposes, and the PUTROOTFH, LOOKUP subseries is processed as according to Section

一連のn個のファイルハンドル操作の場合、サーバはNFS4ERR_WRONGSECを最初のN-1に返却してはいけませんFileHandle操作に必要です。NTH PUT FILEHANDLE操作は、あたかもその操作のサマリーの最初のものであるかのように処理されます。たとえば、サーバーがこの一連の操作で複合要求を受信した場合は、PUTFH、PUTROOTFH、LOOKUP - その後、PUTFH操作はNFS4ERR_WRONGSECの目的で無視され、PUTROOTFH、ルックアップサブシリーズはセクション2.6.3.1に従って処理されます。1.3。 Put Filehandle Operation + LOOKUP (or OPEN of an Existing Name) FileHandleの操作検索(または既存の名前の開き)を入れる

This situation also applies to a put filehandle operation followed by a LOOKUP or an OPEN operation that specifies an existing component name.

このような状況は、PUT FileHandleの操作に続くルックアップまたは既存のコンポーネント名を指定するオープン操作にも適用されます。

In this situation, the client is potentially crossing a security policy boundary, and the set of security tuples the parent directory supports may differ from those of the child. The server implementation may decide whether to impose any restrictions on security policy administration. There are at least three approaches (sec_policy_child is the tuple set of the child export, sec_policy_parent is that of the parent).


(a) sec_policy_child <= sec_policy_parent (<= for subset). This means that the set of security tuples specified on the security policy of a child directory is always a subset of its parent directory.

(a)sec_policy_child <= sec_policy_parent(<=サブセットの場合)。つまり、子ディレクトリのセキュリティポリシーで指定されたセキュリティタプルのセットは、常にその親ディレクトリのサブセットです。

   (b)  sec_policy_child ^ sec_policy_parent != {} (^ for intersection,
        {} for the empty set).  This means that the set of security
        tuples specified on the security policy of a child directory
        always has a non-empty intersection with that of the parent.
   (c)  sec_policy_child ^ sec_policy_parent == {}.  This means that the
        set of security tuples specified on the security policy of a
        child directory may not intersect with that of the parent.  In
        other words, there are no restrictions on how the system
        administrator may set up these tuples.

In order for a server to support approaches (b) (for the case when a client chooses a flavor that is not a member of sec_policy_parent) and (c), the put filehandle operation cannot return NFS4ERR_WRONGSEC when there is a security tuple mismatch. Instead, it should be returned from the LOOKUP (or OPEN by existing component name) that follows.


Since the above guideline does not contradict approach (a), it should be followed in general. Even if approach (a) is implemented, it is possible for the security tuple used to be acceptable for the target of LOOKUP but not for the filehandles used in the put filehandle operation. The put filehandle operation could be a PUTROOTFH or PUTPUBFH, where the client cannot know the security tuples for the root or public filehandle. Or the security policy for the filehandle used by the put filehandle operation could have changed since the time the filehandle was obtained.

上記のガイドラインはアプローチ(A)と矛盾しないので、それは一般的に従うべきです。アプローチ(a)が実装されていても、セキュリティタプルがルックアップのターゲットに対して許容されるが、PUTファイルハンドル操作で使用されるファイルハンドルに対しては受け入れられないことが可能である。PUT FileHandle操作はPUTROOTFHまたはPUTPUBFHで、クライアントはルートまたはパブリックファイルハンドルのセキュリティタプルを知ることができません。またはPUT FileHandle操作で使用されているFileHandleのセキュリティポリシーは、ファイルハンドルが取得された時刻から変更された可能性があります。

Therefore, an NFSv4.1 server MUST NOT return NFS4ERR_WRONGSEC in response to the put filehandle operation if the operation is immediately followed by a LOOKUP or an OPEN by component name.

したがって、操作に直ちにルックアップまたはコンポーネント名が開くと、PUTファイルハンドル操作に応答してNFSV4.1サーバーを返さないでください。 Put Filehandle Operation + LOOKUPP FileHandle操作ルックアップを入れる

Since SECINFO only works its way down, there is no way LOOKUPP can return NFS4ERR_WRONGSEC without SECINFO_NO_NAME. SECINFO_NO_NAME solves this issue via style SECINFO_STYLE4_PARENT, which works in the opposite direction as SECINFO. As with Section, a put filehandle operation that is followed by a LOOKUPP MUST NOT return NFS4ERR_WRONGSEC. If the server does not support SECINFO_NO_NAME, the client's only recourse is to send the put filehandle operation, LOOKUPP, GETFH sequence of operations with every security tuple it supports.

SecInfoはその途中でのみ機能するため、Lookuppがsecinfo_no_nameなしでNFS4ERR_WRONGSECを返す方法はありません。secInfo_no_nameはスタイルSecInfo_Style4_Parentを介してこの問題を解決します。これはSecInfoとして反対方向に機能します。セクション2.と同様に、Lookuppが続くPUTファイルハンドル操作はNFS4ERR_WRONGSECを返してはいけません。サーバーがSECINFO_NO_NAMEをサポートしていない場合、クライアントの専用契約は、PUT FileHandle操作、Lookupp、GetFHのgetfhの順序をサポートするすべてのセキュリティタプルを使用して送信します。

Regardless of whether SECINFO_NO_NAME is supported, an NFSv4.1 server MUST NOT return NFS4ERR_WRONGSEC in response to a put filehandle operation if the operation is immediately followed by a LOOKUPP.

SECINFO_NO_NAMEがサポートされているかどうかにかかわらず、操作が直ちにLookUppが続く場合に、PUTファイルハンドル操作に応答してNFSV4.1サーバーを返さないでください。 Put Filehandle Operation + SECINFO/SECINFO_NO_NAME fileHandleオペレーションSecInfo / secInfo_no_nameを入れる

A security-sensitive client is allowed to choose a strong security tuple when querying a server to determine a file object's permitted security tuples. The security tuple chosen by the client does not have to be included in the tuple list of the security policy of either the parent directory indicated in the put filehandle operation or the child file object indicated in SECINFO (or any parent directory indicated in SECINFO_NO_NAME). Of course, the server has to be configured for whatever security tuple the client selects; otherwise, the request will fail at the RPC layer with an appropriate authentication error.


In theory, there is no connection between the security flavor used by SECINFO or SECINFO_NO_NAME and those supported by the security policy. But in practice, the client may start looking for strong flavors from those supported by the security policy, followed by those in the REQUIRED set.


The NFSv4.1 server MUST NOT return NFS4ERR_WRONGSEC to a put filehandle operation that is immediately followed by SECINFO or SECINFO_NO_NAME. The NFSv4.1 server MUST NOT return NFS4ERR_WRONGSEC from SECINFO or SECINFO_NO_NAME.

NFSV4.1サーバーは、SecInfoまたはSecInfo_no_nameが続くPUT FileHandle操作にNFS4ERR_WRONGSECを返さないでください。NFSV4.1サーバーはSECINFOまたはSECINFO_NO_NAMEからNFS4ERR_WRONGSECを返さないでください。 Put Filehandle Operation + Nothing FileHandle操作を入れて

The NFSv4.1 server MUST NOT return NFS4ERR_WRONGSEC.

NFSV4.1サーバーはNFS4ERR_WRONGSECを返さないでください。 Put Filehandle Operation + Anything Else FileHandle操作を他のものにしてください

"Anything Else" includes OPEN by filehandle.


The security policy enforcement applies to the filehandle specified in the put filehandle operation. Therefore, the put filehandle operation MUST return NFS4ERR_WRONGSEC when there is a security tuple mismatch. This avoids the complexity of adding NFS4ERR_WRONGSEC as an allowable error to every other operation.

セキュリティポリシーの強制は、PUT FileHandle操作で指定されたファイルハンドルに適用されます。そのため、セキュリティタプルの不一致がある場合は、PUTファイルハンドル操作がNFS4ERR_WRONGSECを返す必要があります。これにより、NFS4ERR_WRONGSECを他のすべての操作に許容エラーとして追加することが複雑になります。

A COMPOUND containing the series put filehandle operation + SECINFO_NO_NAME (style SECINFO_STYLE4_CURRENT_FH) is an efficient way for the client to recover from NFS4ERR_WRONGSEC.

シリーズPUT FILE Handle Operation SECINFO_NO_NAME(STYLE SECINFO_STYLE4_CURRENT_FH)を含むコンパウンドは、クライアントがNFS4ERR_WRONGSECから回復するための効率的な方法です。

The NFSv4.1 server MUST NOT return NFS4ERR_WRONGSEC to any operation other than a put filehandle operation, LOOKUP, LOOKUPP, and OPEN (by component name).

NFSV4.1サーバーは、PUT FILEHANDLE操作、ルックアップ、LookUpp、Open(コンポーネント名)以外の操作にNFS4ERR_WRONGSECを返さないでください。 Operations after SECINFO and SECINFO_NO_NAME secinfoとsecinfo_no_nameの後の操作

Suppose a client sends a COMPOUND procedure containing the series SEQUENCE, PUTFH, SECINFO_NONAME, READ, and suppose the security tuple used does not match that required for the target file. By rule (see Section, neither PUTFH nor SECINFO_NO_NAME can return NFS4ERR_WRONGSEC. By rule (see Section, READ cannot return NFS4ERR_WRONGSEC. The issue is resolved by the fact that SECINFO and SECINFO_NO_NAME consume the current filehandle (note that this is a change from NFSv4.0). This leaves no current filehandle for READ to use, and READ returns NFS4ERR_NOFILEHANDLE.

クライアントがシリーズシーケンス、putfh、secinfo_noname、読み取り、使用されているセキュリティタプルがターゲットファイルに必要なものと一致しないとします。ルール(項参照)では、putfhもsecinfo_no_nameもNFS4ERR_WRONGSECを返すことはできません。規則別(項を参照)、読み取りはNFS4ERR_WRONGSECを返すことができません。この問題は、secinfoとsecinfo_no_nameが現在のファイルハンドルを消費するという事実によって解決されます(これはNFSv4.0からの変更です)。これにより、読み取りやすく読み取りのための現在のファイルハンドルは残りません。 LINK and RENAME リンクと名前の変更

The LINK and RENAME operations use both the current and saved filehandles. Technically, the server MAY return NFS4ERR_WRONGSEC from LINK or RENAME if the security policy of the saved filehandle rejects the security flavor used in the COMPOUND request's credentials. If the server does so, then if there is no intersection between the security policies of saved and current filehandles, this means that it will be impossible for the client to perform the intended LINK or RENAME operation.


For example, suppose the client sends this COMPOUND request: SEQUENCE, PUTFH bFH, SAVEFH, PUTFH aFH, RENAME "c" "d", where filehandles bFH and aFH refer to different directories. Suppose no common security tuple exists between the security policies of aFH and bFH. If the client sends the request using credentials acceptable to bFH's security policy but not aFH's policy, then the PUTFH aFH operation will fail with NFS4ERR_WRONGSEC. After a SECINFO_NO_NAME request, the client sends SEQUENCE, PUTFH bFH, SAVEFH, PUTFH aFH, RENAME "c" "d", using credentials acceptable to aFH's security policy but not bFH's policy. The server returns NFS4ERR_WRONGSEC on the RENAME operation.

たとえば、クライアントがこの複合要求を送信します。シーケンス、PUTFH BFH、SAVEFH、PUTFH AFH、ファイルハンドルBFHとAFHの名前を変更します。ここで、FileHandles BFHとAFHは別のディレクトリを参照します。AFHとBFHのセキュリティポリシーの間に共通のセキュリティタプルが存在しないとします。クライアントがBFHのセキュリティポリシーに受け入れられるがAFHのポリシーを使用して要求を送信した場合、PUTFHAFH操作はNFS4ERR_WRONGSECで失敗します。secInfo_no_name要求の後、クライアントは、AFHのセキュリティポリシーに受け入れられるがBFHのポリシーに受け入れられる認証情報を使用して、クライアントはシーケンス、PUTFH BFH、SAVEFH、PUTFH AFHを送信します。サーバーは名前変更操作でNFS4ERR_WRONGSECを返します。

To prevent a client from an endless sequence of a request containing LINK or RENAME, followed by a request containing SECINFO_NO_NAME or SECINFO, the server MUST detect when the security policies of the current and saved filehandles have no mutually acceptable security tuple, and MUST NOT return NFS4ERR_WRONGSEC from LINK or RENAME in that situation. Instead the server MUST do one of two things:


* The server can return NFS4ERR_XDEV.

* サーバーはNFS4ERR_XDEVを返すことができます。

* The server can allow the security policy of the current filehandle to override that of the saved filehandle, and so return NFS4_OK.

* サーバーは、現在のファイルハンドルのセキュリティポリシーを保存したファイルハンドルのそれをオーバーライドすることを許可することができますので、NFS4_OKを返します。

2.7. Minor Versioning
2.7. マイナーバージョン管理

To address the requirement of an NFS protocol that can evolve as the need arises, the NFSv4.1 protocol contains the rules and framework to allow for future minor changes or versioning.


The base assumption with respect to minor versioning is that any future accepted minor version will be documented in one or more Standards Track RFCs. Minor version 0 of the NFSv4 protocol is represented by [37], and minor version 1 is represented by this RFC. The COMPOUND and CB_COMPOUND procedures support the encoding of the minor version being requested by the client.


The following items represent the basic rules for the development of minor versions. Note that a future minor version may modify or add to the following rules as part of the minor version definition.


1. Procedures are not added or deleted.

1. 手順は追加または削除されません。

To maintain the general RPC model, NFSv4 minor versions will not add to or delete procedures from the NFS program.


2. Minor versions may add operations to the COMPOUND and CB_COMPOUND procedures.

2. マイナーバージョンは、複合およびCB_COMPOUND手順に操作を追加することができます。

The addition of operations to the COMPOUND and CB_COMPOUND procedures does not affect the RPC model.


* Minor versions may append attributes to the bitmap4 that represents sets of attributes and to the fattr4 that represents sets of attribute values.

* マイナーバージョンは、属性のセットと属性値のセットを表すFATTR4に属性を追加することがあります。

This allows for the expansion of the attribute model to allow for future growth or adaptation.


* Minor version X must append any new attributes after the last documented attribute.

* マイナーバージョンXは、最後の文書化された属性の後に新しい属性を追加する必要があります。

Since attribute results are specified as an opaque array of per-attribute, XDR-encoded results, the complexity of adding new attributes in the midst of the current definitions would be too burdensome.


3. Minor versions must not modify the structure of an existing operation's arguments or results.

3. マイナーバージョンは、既存の操作の引数または結果の構造を変更してはなりません。

Again, the complexity of handling multiple structure definitions for a single operation is too burdensome. New operations should be added instead of modifying existing structures for a minor version.


This rule does not preclude the following adaptations in a minor version:


* adding bits to flag fields, such as new attributes to GETATTR's bitmap4 data type, and providing corresponding variants of opaque arrays, such as a notify4 used together with such bitmaps

* GetAttrのBitmap4データ型への新しい属性などのFlagフィールドにビットを追加し、そのようなビットマップと一緒に使用されるNotify4のような不透明配列の亜種を提供します。

* adding bits to existing attributes like ACLs that have flag words

* フラグ単語を持つACLのような既存の属性にビットを追加する

* extending enumerated types (including NFS4ERR_*) with new values

* 新しい値で列挙型(NFS4ERR_ *を含む)の拡張

* adding cases to a switched union

* 交換ユニオンにケースを追加する

4. Minor versions must not modify the structure of existing attributes.

4. マイナーバージョンは、既存の属性の構造を変更してはいけません。

5. Minor versions must not delete operations.

5. マイナーバージョンは操作を削除しないでください。

This prevents the potential reuse of a particular operation "slot" in a future minor version.


6. Minor versions must not delete attributes.

6. マイナーバージョンは属性を削除しないでください。

7. Minor versions must not delete flag bits or enumeration values.

7. マイナーバージョンは、フラグビットまたは列挙値を削除しないでください。

8. Minor versions may declare an operation MUST NOT be implemented.

8. マイナーバージョンは、操作を宣言してはいけません。

Specifying that an operation MUST NOT be implemented is equivalent to obsoleting an operation. For the client, it means that the operation MUST NOT be sent to the server. For the server, an NFS error can be returned as opposed to "dropping" the request as an XDR decode error. This approach allows for the obsolescence of an operation while maintaining its structure so that a future minor version can reintroduce the operation.


1. Minor versions may declare that an attribute MUST NOT be implemented.

1. マイナーバージョンは、属性が実装されてはならないことを宣言することができます。

2. Minor versions may declare that a flag bit or enumeration value MUST NOT be implemented.

2. マイナーバージョンは、フラグビットまたは列挙値を実装してはならないことを宣言することができます。

9. Minor versions may downgrade features from REQUIRED to RECOMMENDED, or RECOMMENDED to OPTIONAL.

9. マイナーバージョンは、必須から推奨されているのをダウングレードすること、またはオプションに推奨されることがあります。

10. Minor versions may upgrade features from OPTIONAL to RECOMMENDED, or RECOMMENDED to REQUIRED.

10. マイナーバージョンは、推奨されている、または必要とされることをお勧めします。

11. A client and server that support minor version X SHOULD support minor versions zero through X-1 as well.

11. マイナーバージョンXをサポートするクライアントとサーバーは、マイナーバージョンゼロからX-1をサポートする必要があります。

12. Except for infrastructural changes, a minor version must not introduce REQUIRED new features.

12. インフラストラクチャの変更を除いて、マイナーバージョンは必要な新機能を導入してはいけません。

This rule allows for the introduction of new functionality and forces the use of implementation experience before designating a feature as REQUIRED. On the other hand, some classes of features are infrastructural and have broad effects. Allowing infrastructural features to be RECOMMENDED or OPTIONAL complicates implementation of the minor version.


13. A client MUST NOT attempt to use a stateid, filehandle, or similar returned object from the COMPOUND procedure with minor version X for another COMPOUND procedure with minor version Y, where X != Y.

13. マイナーバージョンyを持つ別の複合手順で、マイナーバージョンXを使用して、マイナーバージョンXを使用して、StateID、FileHandle、または類似の返品オブジェクトを、マイナーバージョンXで使用してはいけません。

2.8. Non-RPC-Based Security Services
2.8. 非RPCベースのセキュリティサービス

As described in Section, NFSv4.1 relies on RPC for identification, authentication, integrity, and privacy. NFSv4.1 itself provides or enables additional security services as described in the next several subsections.


2.8.1. Authorization
2.8.1. 承認

Authorization to access a file object via an NFSv4.1 operation is ultimately determined by the NFSv4.1 server. A client can predetermine its access to a file object via the OPEN (Section 18.16) and the ACCESS (Section 18.1) operations.


Principals with appropriate access rights can modify the authorization on a file object via the SETATTR (Section 18.30) operation. Attributes that affect access rights include mode, owner, owner_group, acl, dacl, and sacl. See Section 5.


2.8.2. Auditing
2.8.2. 監査

NFSv4.1 provides auditing on a per-file object basis, via the acl and sacl attributes as described in Section 6. It is outside the scope of this specification to specify audit log formats or management policies.


2.8.3. Intrusion Detection
2.8.3. 侵入検知

NFSv4.1 provides alarm control on a per-file object basis, via the acl and sacl attributes as described in Section 6. Alarms may serve as the basis for intrusion detection. It is outside the scope of this specification to specify heuristics for detecting intrusion via alarms.


2.9. Transport Layers
2.9. 輸送層
2.9.1. REQUIRED and RECOMMENDED Properties of Transports
2.9.1. トランスポートの必須で推奨されるプロパティ

NFSv4.1 works over Remote Direct Memory Access (RDMA) and non-RDMA-based transports with the following attributes:


* The transport supports reliable delivery of data, which NFSv4.1 requires but neither NFSv4.1 nor RPC has facilities for ensuring [41].

* トランスポートは信頼できるデータの配信をサポートしています。これらのNFSV4.1は必要ですが、NFSV4.1もRPCも確実にするための機能を持っていません。

* The transport delivers data in the order it was sent. Ordered delivery simplifies detection of transmit errors, and simplifies the sending of arbitrary sized requests and responses via the record marking protocol [3].

* トランスポートは送信された順序でデータを配信します。順序付けられた配信は送信エラーの検出を簡素化し、レコードマーキングプロトコルを介して任意のサイズの要求と応答の送信を簡素化します[3]。

Where an NFSv4.1 implementation supports operation over the IP network protocol, any transport used between NFS and IP MUST be among the IETF-approved congestion control transport protocols. At the time this document was written, the only two transports that had the above attributes were TCP and the Stream Control Transmission Protocol (SCTP). To enhance the possibilities for interoperability, an NFSv4.1 implementation MUST support operation over the TCP transport protocol.


Even if NFSv4.1 is used over a non-IP network protocol, it is RECOMMENDED that the transport support congestion control.


It is permissible for a connectionless transport to be used under NFSv4.1; however, reliable and in-order delivery of data combined with congestion control by the connectionless transport is REQUIRED. As a consequence, UDP by itself MUST NOT be used as an NFSv4.1 transport. NFSv4.1 assumes that a client transport address and server transport address used to send data over a transport together constitute a connection, even if the underlying transport eschews the concept of a connection.


2.9.2. Client and Server Transport Behavior
2.9.2. クライアントとサーバーのトランスポート動作

If a connection-oriented transport (e.g., TCP) is used, the client and server SHOULD use long-lived connections for at least three reasons:


1. This will prevent the weakening of the transport's congestion control mechanisms via short-lived connections.

1. これにより、短命の接続による輸送の輻輳制御メカニズムの弱化が防止されます。

2. This will improve performance for the WAN environment by eliminating the need for connection setup handshakes.

2. これにより、接続設定ハンドシェイクの必要性を排除することで、WAN環境のパフォーマンスが向上します。

3. The NFSv4.1 callback model differs from NFSv4.0, and requires the client and server to maintain a client-created backchannel (see Section for the server to use.

3. NFSV4.1コールバックモデルはNFSV4.0とは異なり、サーバーが使用するためのクライアント作成のバックチャネル(セクション2.10.3.1を参照)を維持するようにクライアントとサーバーが必要です。

In order to reduce congestion, if a connection-oriented transport is used, and the request is not the NULL procedure:


* A requester MUST NOT retry a request unless the connection the request was sent over was lost before the reply was received.

* 返信が受信される前に、要求が送信された接続が拒否されていない限り、リクエスタはリクエストを再試行してはいけません。

* A replier MUST NOT silently drop a request, even if the request is a retry. (The silent drop behavior of RPCSEC_GSS [4] does not apply because this behavior happens at the RPCSEC_GSS layer, a lower layer in the request processing.) Instead, the replier SHOULD return an appropriate error (see Section, or it MAY disconnect the connection.

* リクエストが再試行しても、リプライアはリクエストを黙ってはいけません。(RPCSEC_GSSのサイレントドロップ動作は、RPCSEC_GSSレイヤであるRPCSEC_GSSレイヤ、リクエスト処理内の下位レイヤーで発生するため、適用されません。)代わりに、レプリタは適切なエラーを返す(セクション2.10.6.1を参照)、またはそれを参照)接続を切断する可能性があります。

When sending a reply, the replier MUST send the reply to the same full network address (e.g., if using an IP-based transport, the source port of the requester is part of the full network address) from which the requester sent the request. If using a connection-oriented transport, replies MUST be sent on the same connection from which the request was received.


If a connection is dropped after the replier receives the request but before the replier sends the reply, the replier might have a pending reply. If a connection is established with the same source and destination full network address as the dropped connection, then the replier MUST NOT send the reply until the requester retries the request. The reason for this prohibition is that the requester MAY retry a request over a different connection (provided that connection is associated with the original request's session).


When using RDMA transports, there are other reasons for not tolerating retries over the same connection:


* RDMA transports use "credits" to enforce flow control, where a credit is a right to a peer to transmit a message. If one peer were to retransmit a request (or reply), it would consume an additional credit. If the replier retransmitted a reply, it would certainly result in an RDMA connection loss, since the requester would typically only post a single receive buffer for each request. If the requester retransmitted a request, the additional credit consumed on the server might lead to RDMA connection failure unless the client accounted for it and decreased its available credit, leading to wasted resources.

* RDMAトランスポートは、クレジットがメッセージを送信するピアの権利であるフロー制御を強制するために「クレジット」を使用します。1つのピアがリクエスト(または返信)を再送信することになった場合は、追加のクレジットを消費します。リクエスタが各要求に対して単一の受信バッファを投稿するだけなので、レプリタが応答を再送信した場合、それは確かにRDMA接続損失を引き起こすでしょう。リクエスタが要求を再送信した場合、クライアントがITを説明し、利用可能なクレジットが低下しない限り、サーバー上で消費された追加のクレジットがRDMA接続の失敗につながる可能性があります。

* RDMA credits present a new issue to the reply cache in NFSv4.1. The reply cache may be used when a connection within a session is lost, such as after the client reconnects. Credit information is a dynamic property of the RDMA connection, and stale values must not be replayed from the cache. This implies that the reply cache contents must not be blindly used when replies are sent from it, and credit information appropriate to the channel must be refreshed by the RPC layer.

* RDMAクレジットは、NFSV4.1の返信キャッシュに新しい問題を提示します。クライアントが再接続した後など、セッション内の接続が失われたときに返信キャッシュを使用できます。クレジット情報はRDMA接続の動的プロパティであり、古い値をキャッシュから再生しないでください。これは、返信が送信されたときに返信キャッシュの内容を盲目的に使用されてはならず、チャネルに適したクレジット情報はRPCレイヤによってリフレッシュされなければならないことを意味します。

In addition, as described in Section, while a session is active, the NFSv4.1 requester MUST NOT stop waiting for a reply.


2.9.3. Ports
2.9.3. 港

Historically, NFSv3 servers have listened over TCP port 2049. The registered port 2049 [42] for the NFS protocol should be the default configuration. NFSv4.1 clients SHOULD NOT use the RPC binding protocols as described in [43].

歴史的に、NFSV3サーバーはTCPポート2049を介してリッスンされています.NFSプロトコルの登録ポート2049 [42]は、デフォルトの構成になります。NFSV4.1クライアントは[43]に記載されているようにRPCバインディングプロトコルを使用しないでください。

2.10. Session
2.10. セッション

NFSv4.1 clients and servers MUST support and MUST use the session feature as described in this section.


2.10.1. Motivation and Overview
2.10.1. 動機と概要

Previous versions and minor versions of NFS have suffered from the following:


* Lack of support for Exactly Once Semantics (EOS). This includes lack of support for EOS through server failure and recovery.

* 正確に一度だけサポートされていない(EOS)。これには、サーバーの障害と回復によるEOSのサポートの欠如が含まれています。

* Limited callback support, including no support for sending callbacks through firewalls, and races between replies to normal requests and callbacks.

* ファイアウォールを介してコールバックを送信するためのサポートを含まず、正規の要求とコールバックに対するレーセレスを含む、リマンスコールバックサポート。

* Limited trunking over multiple network paths.

* 複数のネットワーク経路上の限られたトランキング。

* Requiring machine credentials for fully secure operation.

* 完全に安全な操作のための機械認証情報を必要とします。

Through the introduction of a session, NFSv4.1 addresses the above shortfalls with practical solutions:


* EOS is enabled by a reply cache with a bounded size, making it feasible to keep the cache in persistent storage and enable EOS through server failure and recovery. One reason that previous revisions of NFS did not support EOS was because some EOS approaches often limited parallelism. As will be explained in Section 2.10.6, NFSv4.1 supports both EOS and unlimited parallelism.

* EOSは有効なサイズの応答キャッシュによって有効になり、キャッシュを永続的なストレージに保持し、サーバーの障害と回復を通じてEOSを有効にします。NFSの以前の改訂がEOSをサポートしていなかった1つの理由は、EOSアプローチが頻繁に限られた並列処理によってあったためです。セクション2.10.6で説明されるように、NFSV4.1はEOSと無制限の並列処理の両方をサポートしています。

* The NFSv4.1 client (defined in Section 1.7) creates transport connections and provides them to the server to use for sending callback requests, thus solving the firewall issue (Section 18.34). Races between responses from client requests and callbacks caused by the requests are detected via the session's sequencing properties that are a consequence of EOS (Section

* NFSV4.1クライアント(セクション1.7で定義)はトランスポート接続を作成し、それらをコールバック要求の送信に使用するサーバーに提供し、ファイアウォールの問題を解決します(セクション18.34)。クライアント要求からの応答とリクエストによって引き起こされるコールバックの間のレースは、EOSの結果であるセッションのシーケンスプロパティによって検出されます(項)。

* The NFSv4.1 client can associate an arbitrary number of connections with the session, and thus provide trunking (Section 2.10.5).

* NFSV4.1クライアントは、任意の数の接続をセッションと関連付けることができ、したがってトランキングを提供する(2.10.5項)。

* The NFSv4.1 client and server produce a session key independent of client and server machine credentials which can be used to compute a digest for protecting critical session management operations (Section

* NFSV4.1クライアントとサーバーは、重要なセッション管理操作を保護するためのダイジェストを計算するために使用できるクライアントとサーバーのマシンの認証情報とは無関係にセッションキーを作成します(セクション2.10.8.3)。

* The NFSv4.1 client can also create secure RPCSEC_GSS contexts for use by the session's backchannel that do not require the server to authenticate to a client machine principal (Section

* NFSV4.1クライアントは、サーバーがクライアントマシンプリンシパルの認証を要求しないセッションのBackChannelが使用するための安全なRPCSEC_GSSコンテキストを作成することもできます(セクション2.10.8.2)。

A session is a dynamically created, long-lived server object created by a client and used over time from one or more transport connections. Its function is to maintain the server's state relative to the connection(s) belonging to a client instance. This state is entirely independent of the connection itself, and indeed the state exists whether or not the connection exists. A client may have one or more sessions associated with it so that client-associated state may be accessed using any of the sessions associated with that client's client ID, when connections are associated with those sessions. When no connections are associated with any of a client ID's sessions for an extended time, such objects as locks, opens, delegations, layouts, etc. are subject to expiration. The session serves as an object representing a means of access by a client to the associated client state on the server, independent of the physical means of access to that state.


A single client may create multiple sessions. A single session MUST NOT serve multiple clients.


2.10.2. NFSv4 Integration
2.10.2. NFSV4統合

Sessions are part of NFSv4.1 and not NFSv4.0. Normally, a major infrastructure change such as sessions would require a new major version number to an Open Network Computing (ONC) RPC program like NFS. However, because NFSv4 encapsulates its functionality in a single procedure, COMPOUND, and because COMPOUND can support an arbitrary number of operations, sessions have been added to NFSv4.1 with little difficulty. COMPOUND includes a minor version number field, and for NFSv4.1 this minor version is set to 1. When the NFSv4 server processes a COMPOUND with the minor version set to 1, it expects a different set of operations than it does for NFSv4.0. NFSv4.1 defines the SEQUENCE operation, which is required for every COMPOUND that operates over an established session, with the exception of some session administration operations, such as DESTROY_SESSION (Section 18.37).

セッションはNFSv4.1ではなくNFSv4.0の一部です。通常、セッションなどの主要なインフラストラクチャの変更は、NFSのようなオープンネットワークコンピューティング(ONC)RPCプログラムへの新しいメジャーバージョン番号を必要とするでしょう。しかしながら、NFSV4は単一の手順でその機能をカプセル化するので、化合物は任意の数の演算をサポートできるため、セッションがほとんど困難でNFSV4.1に追加されました。化合物には、マイナーバージョン番号フィールドが含まれており、NFSV4.1の場合はこのマイナーバージョンは1に設定されています.NFSV4サーバーがマイナーバージョンを1に設定してコンパウンドを処理すると、NFSv4.0の場合は異なる操作セットが表示されます。。NFSV4.1は、Destroy_Sessionなどのセッション管理操作を除いて、確立されたセッションを介して動作するすべての化合物に必要なシーケンス操作を定義します(セクション18.37)。 SEQUENCE and CB_SEQUENCE シーケンスとCB_Sequence

In NFSv4.1, when the SEQUENCE operation is present, it MUST be the first operation in the COMPOUND procedure. The primary purpose of SEQUENCE is to carry the session identifier. The session identifier associates all other operations in the COMPOUND procedure with a particular session. SEQUENCE also contains required information for maintaining EOS (see Section 2.10.6). Session-enabled NFSv4.1 COMPOUND requests thus have the form:


       | tag | minorversion | numops    |SEQUENCE op | op + args | ...
       |     |   (== 1)     | (limited) |  + args    |           |

and the replies have the form:


       |last status | tag | numres |status + SEQUENCE op + results |  //
               // status + op + results | ...

A CB_COMPOUND procedure request and reply has a similar form to COMPOUND, but instead of a SEQUENCE operation, there is a CB_SEQUENCE operation. CB_COMPOUND also has an additional field called "callback_ident", which is superfluous in NFSv4.1 and MUST be ignored by the client. CB_SEQUENCE has the same information as SEQUENCE, and also includes other information needed to resolve callback races (Section

CB_COMPOUND手続き要求と応答は、複合と同様の形式を持ちますが、シーケンス操作の代わりにCB_SEQUENCE動作があります。CB_COMPOUNDには、NFSV4.1では不要であり、クライアントによって無視される必要があります。CB_Sequenceはシーケンスと同じ情報を持ち、コールバックレースを解決するために必要な他の情報も含まれています(セクション2.10.6.3)。 Client ID and Session Association クライアントIDとセッションの関連付け

Each client ID (Section 2.4) can have zero or more active sessions. A client ID and associated session are required to perform file access in NFSv4.1. Each time a session is used (whether by a client sending a request to the server or the client replying to a callback request from the server), the state leased to its associated client ID is automatically renewed.


State (which can consist of share reservations, locks, delegations, and layouts (Section 1.8.4)) is tied to the client ID. Client state is not tied to any individual session. Successive state changing operations from a given state owner MAY go over different sessions, provided the session is associated with the same client ID. A callback MAY arrive over a different session than that of the request that originally acquired the state pertaining to the callback. For example, if session A is used to acquire a delegation, a request to recall the delegation MAY arrive over session B if both sessions are associated with the same client ID. Sections and discuss the security considerations around callbacks.


2.10.3. Channels
2.10.3. チャンネル

A channel is not a connection. A channel represents the direction ONC RPC requests are sent.

チャネルは接続ではありません。チャネルはONC RPC要求を送信する方向を表します。

Each session has one or two channels: the fore channel and the backchannel. Because there are at most two channels per session, and because each channel has a distinct purpose, channels are not assigned identifiers.


The fore channel is used for ordinary requests from the client to the server, and carries COMPOUND requests and responses. A session always has a fore channel.


The backchannel is used for callback requests from server to client, and carries CB_COMPOUND requests and responses. Whether or not there is a backchannel is decided by the client; however, many features of NFSv4.1 require a backchannel. NFSv4.1 servers MUST support backchannels.


Each session has resources for each channel, including separate reply caches (see Section Note that even the backchannel requires a reply cache (or, at least, a slot table in order to detect retries) because some callback operations are non-idempotent.

各セッションには、個別の返信キャッシュを含む、各チャネルのリソースがあります(セクション2.10.6.1を参照)。バックチャネルでさえ、いくつかのコールバック操作はIDEmpotentであるため、返信キャッシュ(または少なくとも再試行を検出するためにスロットテーブル)を必要とすることに注意してください。 Association of Connections, Channels, and Sessions 接続、チャンネル、セッションの関連付け

Each channel is associated with zero or more transport connections (whether of the same transport protocol or different transport protocols). A connection can be associated with one channel or both channels of a session; the client and server negotiate whether a connection will carry traffic for one channel or both channels via the CREATE_SESSION (Section 18.36) and the BIND_CONN_TO_SESSION (Section 18.34) operations. When a session is created via CREATE_SESSION, the connection that transported the CREATE_SESSION request is automatically associated with the fore channel, and optionally the backchannel. If the client specifies no state protection (Section 18.35) when the session is created, then when SEQUENCE is transmitted on a different connection, the connection is automatically associated with the fore channel of the session specified in the SEQUENCE operation.

各チャネルは、0個以上のトランスポート接続と関連付けられています(同じトランスポートプロトコルまたは異なるトランスポートプロトコルであろう)。接続は、セッションの1つのチャネルまたは両方のチャネルに関連付けることができます。クライアントとサーバーは、CREATE_SESSION(セクション18.36)とBIND_CONN_TO_SESSION(セクション18.34)の操作を介して、接続が1つのチャネルまたは両方のチャンネルのトラフィックを搬送するかどうかをネゴシエートします。CREATE_SESSIONを介してセッションが作成されると、CREATE_SESSION要求を転送した接続は自動的に前のチャネル、およびオプションでバックチャネルに関連付けられます。クライアントがState Protectionを指定していない場合(セクション18.35)セッションが作成されたときに、シーケンスが異なる接続で送信されると、接続はシーケンス操作で指定されたセッションの前のチャネルに自動的に関連付けられます。

A connection's association with a session is not exclusive. A connection associated with the channel(s) of one session may be simultaneously associated with the channel(s) of other sessions including sessions associated with other client IDs.


It is permissible for connections of multiple transport types to be associated with the same channel. For example, both TCP and RDMA connections can be associated with the fore channel. In the event an RDMA and non-RDMA connection are associated with the same channel, the maximum number of slots SHOULD be at least one more than the total number of RDMA credits (Section This way, if all RDMA credits are used, the non-RDMA connection can have at least one outstanding request. If a server supports multiple transport types, it MUST allow a client to associate connections from each transport to a channel.


It is permissible for a connection of one type of transport to be associated with the fore channel, and a connection of a different type to be associated with the backchannel.


2.10.4. Server Scope
2.10.4. サーバースコープ

Servers each specify a server scope value in the form of an opaque string eir_server_scope returned as part of the results of an EXCHANGE_ID operation. The purpose of the server scope is to allow a group of servers to indicate to clients that a set of servers sharing the same server scope value has arranged to use distinct values of opaque identifiers so that the two servers never assign the same value to two distinct objects. Thus, the identifiers generated by two servers within that set can be assumed compatible so that, in certain important cases, identifiers generated by one server in that set may be presented to another server of the same scope.


The use of such compatible values does not imply that a value generated by one server will always be accepted by another. In most cases, it will not. However, a server will not inadvertently accept a value generated by another server. When it does accept it, it will be because it is recognized as valid and carrying the same meaning as on another server of the same scope.


When servers are of the same server scope, this compatibility of values applies to the following identifiers:


* Filehandle values. A filehandle value accepted by two servers of the same server scope denotes the same object. A WRITE operation sent to one server is reflected immediately in a READ sent to the other.

* ファイルハンドル値同じサーバースコープの2つのサーバーによって受け入れられたファイルハンドル値は同じオブジェクトを表します。1つのサーバに送信された書き込み操作は、もう一方のサーバに送信された読み取りに反映されます。

* Server owner values. When the server scope values are the same, server owner value may be validly compared. In cases where the server scope values are different, server owner values are treated as different even if they contain identical strings of bytes.

* サーバーの所有者の値。サーバースコープ値が同じ場合は、サーバーの所有者の値が有効に比較される可能性があります。サーバースコープ値が異なる場合、サーバーの所有者の値は、同一のバイト文字列を含む場合でも、異なるものとして扱われます。

The coordination among servers required to provide such compatibility can be quite minimal, and limited to a simple partition of the ID space. The recognition of common values requires additional implementation, but this can be tailored to the specific situations in which that recognition is desired.


Clients will have occasion to compare the server scope values of multiple servers under a number of circumstances, each of which will be discussed under the appropriate functional section:


* When server owner values received in response to EXCHANGE_ID operations sent to multiple network addresses are compared for the purpose of determining the validity of various forms of trunking, as described in Section 11.5.2.

* 複数のネットワークアドレスに送信されたExchange_ID操作に応答して受信されたサーバ所有者の値が、セクション11.5.2で説明されているように、さまざまな形式のトランキングの妥当性を判断する目的で比較される。

* When network or server reconfiguration causes the same network address to possibly be directed to different servers, with the necessity for the client to determine when lock reclaim should be attempted, as described in Section

* ネットワークまたはサーバーの再構成が異なるサーバーに同じネットワークアドレスを引き起こす場合、クライアントがロック再生がいつ試行されるかをクライアントに決定する必要がある場合は、セクション8.4.2.1で説明されています。

When two replies from EXCHANGE_ID, each from two different server network addresses, have the same server scope, there are a number of ways a client can validate that the common server scope is due to two servers cooperating in a group.

Exchange_IDからの2つの応答が、2つの異なるサーバーネットワークアドレスから同じサーバースコープを持ち、クライアントがCommon Serverスコープがグループ内に協力している2つのサーバーがあることを検証できる方法がいくつかあります。

* If both EXCHANGE_ID requests were sent with RPCSEC_GSS ([4], [9], [27]) authentication and the server principal is the same for both targets, the equality of server scope is validated. It is RECOMMENDED that two servers intending to share the same server scope and server_owner major_id also share the same principal name. In some cases, this simplifies the client's task of validating server scope.

* 両方のExchange_id要求がRPCSEC_GSS([4]、[9]、[27])で送信され、サーバープリンシパルが両方のターゲットで同じである場合、サーバースコープの平等は検証されます。同じサーバースコープとserver_owner mapear_idを共有するつもりの2つのサーバーも同じプリンシパル名を共有することをお勧めします。場合によっては、これにより、クライアントのサーバースコープを検証するタスクが簡単になります。

* The client may accept the appearance of the second server in the fs_locations or fs_locations_info attribute for a relevant file system. For example, if there is a migration event for a particular file system or there are locks to be reclaimed on a particular file system, the attributes for that particular file system may be used. The client sends the GETATTR request to the first server for the fs_locations or fs_locations_info attribute with RPCSEC_GSS authentication. It may need to do this in advance of the need to verify the common server scope. If the client successfully authenticates the reply to GETATTR, and the GETATTR request and reply containing the fs_locations or fs_locations_info attribute refers to the second server, then the equality of server scope is supported. A client may choose to limit the use of this form of support to information relevant to the specific file system involved (e.g. a file system being migrated).

* クライアントは、関連するファイルシステムのFS_LOCATIONATIONATIONSまたはFS_LOCATIONS_INFO属性内の2番目のサーバーの外観を受け入れることができます。たとえば、特定のファイルシステムのマイグレーションイベントがあるか、特定のファイルシステムで再生されるロックがある場合、その特定のファイルシステムの属性を使用できます。クライアントは、RPCSEC_GSS認証を使用してFS_LOCATIONSまたはFS_LOCATIONS_INFO属性の最初のサーバーにGetAttr要求を送信します。一般的なサーバーの範囲を確認する必要がないようにする必要があるかもしれません。クライアントがGetAttrへの返信を正常に認証し、fs_locationsまたはfs_locations_info属性を含むgetAttr要求と応答が2番目のサーバーを参照してから、サーバースコープの平等がサポートされています。クライアントは、この形式のサポートの使用を関連する特定のファイルシステムに関連する情報(例えば、移行されているファイルシステム)に制限することを選択することができる。

2.10.5. Trunking
2.10.5. 切り捨て

Trunking is the use of multiple connections between a client and server in order to increase the speed of data transfer. NFSv4.1 supports two types of trunking: session trunking and client ID trunking.


In the context of a single server network address, it can be assumed that all connections are accessing the same server, and NFSv4.1 servers MUST support both forms of trunking. When multiple connections use a set of network addresses to access the same server, the server MUST support both forms of trunking. NFSv4.1 servers in a clustered configuration MAY allow network addresses for different servers to use client ID trunking.


Clients may use either form of trunking as long as they do not, when trunking between different server network addresses, violate the servers' mandates as to the kinds of trunking to be allowed (see below). With regard to callback channels, the client MUST allow the server to choose among all callback channels valid for a given client ID and MUST support trunking when the connections supporting the backchannel allow session or client ID trunking to be used for callbacks.


Session trunking is essentially the association of multiple connections, each with potentially different target and/or source network addresses, to the same session. When the target network addresses (server addresses) of the two connections are the same, the server MUST support such session trunking. When the target network addresses are different, the server MAY indicate such support using the data returned by the EXCHANGE_ID operation (see below).


Client ID trunking is the association of multiple sessions to the same client ID. Servers MUST support client ID trunking for two target network addresses whenever they allow session trunking for those same two network addresses. In addition, a server MAY, by presenting the same major server owner ID (Section 2.5) and server scope (Section 2.10.4), allow an additional case of client ID trunking. When two servers return the same major server owner and server scope, it means that the two servers are cooperating on locking state management, which is a prerequisite for client ID trunking.


Distinguishing when the client is allowed to use session and client ID trunking requires understanding how the results of the EXCHANGE_ID (Section 18.35) operation identify a server. Suppose a client sends EXCHANGE_IDs over two different connections, each with a possibly different target network address, but each EXCHANGE_ID operation has the same value in the eia_clientowner field. If the same NFSv4.1 server is listening over each connection, then each EXCHANGE_ID result MUST return the same values of eir_clientid, eir_server_owner.so_major_id, and eir_server_scope. The client can then treat each connection as referring to the same server (subject to verification; see Section below), and it can use each connection to trunk requests and replies. The client's choice is whether session trunking or client ID trunking applies.


Session Trunking. If the eia_clientowner argument is the same in two different EXCHANGE_ID requests, and the eir_clientid, eir_server_owner.so_major_id, eir_server_owner.so_minor_id, and eir_server_scope results match in both EXCHANGE_ID results, then the client is permitted to perform session trunking. If the client has no session mapping to the tuple of eir_clientid, eir_server_owner.so_major_id, eir_server_scope, and eir_server_owner.so_minor_id, then it creates the session via a CREATE_SESSION operation over one of the connections, which associates the connection to the session. If there is a session for the tuple, the client can send BIND_CONN_TO_SESSION to associate the connection to the session.


Of course, if the client does not desire to use session trunking, it is not required to do so. It can invoke CREATE_SESSION on the connection. This will result in client ID trunking as described below. It can also decide to drop the connection if it does not choose to use trunking.


Client ID Trunking. If the eia_clientowner argument is the same in two different EXCHANGE_ID requests, and the eir_clientid, eir_server_owner.so_major_id, and eir_server_scope results match in both EXCHANGE_ID results, then the client is permitted to perform client ID trunking (regardless of whether the eir_server_owner.so_minor_id results match). The client can associate each connection with different sessions, where each session is associated with the same server.


The client completes the act of client ID trunking by invoking CREATE_SESSION on each connection, using the same client ID that was returned in eir_clientid. These invocations create two sessions and also associate each connection with its respective session. The client is free to decline to use client ID trunking by simply dropping the connection at this point.


When doing client ID trunking, locking state is shared across sessions associated with that same client ID. This requires the server to coordinate state across sessions and the client to be able to associate the same locking state with multiple sessions.


It is always possible that, as a result of various sorts of reconfiguration events, eir_server_scope and eir_server_owner values may be different on subsequent EXCHANGE_ID requests made to the same network address.


In most cases, such reconfiguration events will be disruptive and indicate that an IP address formerly connected to one server is now connected to an entirely different one.


Some guidelines on client handling of such situations follow:


* When eir_server_scope changes, the client has no assurance that any IDs that it obtained previously (e.g., filehandles) can be validly used on the new server, and, even if the new server accepts them, there is no assurance that this is not due to accident. Thus, it is best to treat all such state as lost or stale, although a client may assume that the probability of inadvertent acceptance is low and treat this situation as within the next case.

* EIR_SERVER_SCOPEが変更された場合、クライアントには、以前に取得したID(ファイルハンドルなど)が新しいサーバーで有効に使用できること、および新しいサーバーがそれらを受け入れても、これが原因ではないという保証はありません。事故。したがって、クライアントは、不注意による受理の確率が低いと仮定され、次の場合と同じようにこの状況を扱うことができるが、紛失または古い状態のまったく扱うことが最善である。

* When eir_server_scope remains the same and eir_server_owner.so_major_id changes, the client can use the filehandles it has, consider its locking state lost, and attempt to reclaim or otherwise re-obtain its locks. It might find that its filehandle is now stale. However, if NFS4ERR_STALE is not returned, it can proceed to reclaim or otherwise re-obtain its open locking state.

* EIR_SERVER_SCOPEが同じでEIR_SERVER_OWNER.SO_MAJOR_IDのままである場合、クライアントはそれが持つファイルハンドルを使用し、そのロック状態が失われたとみなし、そのロックを再利用するか、またはその他の方法で再取得しようとします。そのファイルハンドルが現在古くなっていることがわかります。ただし、NFS4ERR_STALEが返されない場合は、そのオープンロック状態の再利用またはその他の方法で再取得できます。

* When eir_server_scope and eir_server_owner.so_major_id remain the same, the client has to use the now-current values of eir_server_owner.so_minor_id in deciding on appropriate forms of trunking. This may result in connections being dropped or new sessions being created.

* EIR_SERVER_SCOPEおよびEIR_SERVER_OWNER.SO_MAJOR_IDが同じままである場合、クライアントは適切な形式のトランキングを決定する際にEIR_SERVER_OWNER.SO_MINOR_IDの現在の電流値を使用する必要があります。これにより、接続が削除されたり、新しいセッションが作成されたりする可能性があります。 Verifying Claims of Matching Server Identity マッチングサーバーIDのクレームを確認します

When the server responds using two different connections that claim matching or partially matching eir_server_owner, eir_server_scope, and eir_clientid values, the client does not have to trust the servers' claims. The client may verify these claims before trunking traffic in the following ways:


* For session trunking, clients SHOULD reliably verify if connections between different network paths are in fact associated with the same NFSv4.1 server and usable on the same session, and servers MUST allow clients to perform reliable verification. When a client ID is created, the client SHOULD specify that BIND_CONN_TO_SESSION is to be verified according to the SP4_SSV or SP4_MACH_CRED (Section 18.35) state protection options. For SP4_SSV, reliable verification depends on a shared secret (the SSV) that is established via the SET_SSV (see Section 18.47) operation.

* セッショントランキングの場合、クライアントは、異なるネットワークパス間の接続が同じNFSV4.1サーバーに関連付けられ、同じセッションで使用可能であるかどうかを確実に検証する必要があり、サーバーはクライアントが信頼できる検証を実行できるようにします。クライアントIDが作成されると、クライアントはSP4_SSVまたはSP4_MACH_CRED(セクション18.35)の状態保護オプションに従ってBIND_CONN_TO_SESSIONを検証するように指定する必要があります。SP4_SSVの場合、信頼性の高い検証はSET_SSVを介して確立された共有秘密(SSV)によって異なります(セクション18.47)。

When a new connection is associated with the session (via the BIND_CONN_TO_SESSION operation, see Section 18.34), if the client specified SP4_SSV state protection for the BIND_CONN_TO_SESSION operation, the client MUST send the BIND_CONN_TO_SESSION with RPCSEC_GSS protection, using integrity or privacy, and an RPCSEC_GSS handle created with the GSS SSV mechanism (see Section 2.10.9).

新しい接続がセッションに関連付けられている場合(BIND_CONN_TO_SESSION操作を介して、18.34項を参照)、クライアントがbind_conn_to_session操作のSP4_SSV状態保護を指定した場合、クライアントは、整合性またはプライバシーを使用して、rpcsec_gss保護を使用してbind_conn_to_sessionを送信する必要があります。GSS SSVメカニズムで作成されたハンドル(2.10.9項を参照)。

If the client mistakenly tries to associate a connection to a session of a wrong server, the server will either reject the attempt because it is not aware of the session identifier of the BIND_CONN_TO_SESSION arguments, or it will reject the attempt because the RPCSEC_GSS authentication fails. Even if the server mistakenly or maliciously accepts the connection association attempt, the RPCSEC_GSS verifier it computes in the response will not be verified by the client, so the client will know it cannot use the connection for trunking the specified session.

誤って誤ったサーバーのセッションへの接続を関連付けると、クライアントがBIND_CONN_TO_SESSION引数のセッションIDを認識していないため、サーバーはその試行を拒否します。サーバーが誤ってまたは悪意がある場合でも接続アソシエーションの試行を受け付けても、応答を計算するRPCSEC_GSS Verifierはクライアントによって検証されません。そのため、クライアントは指定されたセッションのトランキングに接続を使用できないことがわかります。

If the client specified SP4_MACH_CRED state protection, the BIND_CONN_TO_SESSION operation will use RPCSEC_GSS integrity or privacy, using the same credential that was used when the client ID was created. Mutual authentication via RPCSEC_GSS assures the client that the connection is associated with the correct session of the correct server.


* For client ID trunking, the client has at least two options for verifying that the same client ID obtained from two different EXCHANGE_ID operations came from the same server. The first option is to use RPCSEC_GSS authentication when sending each EXCHANGE_ID operation. Each time an EXCHANGE_ID is sent with RPCSEC_GSS authentication, the client notes the principal name of the GSS target. If the EXCHANGE_ID results indicate that client ID trunking is possible, and the GSS targets' principal names are the same, the servers are the same and client ID trunking is allowed.

* クライアントIDのトランキングの場合、クライアントには、2つの異なるExchange_ID操作から取得した同じクライアントIDが同じサーバーから取得されたことを確認するための少なくとも2つのオプションがあります。最初のオプションは、各Exchange_ID操作を送信するときにRPCSEC_GSS認証を使用することです。Exchange_IDがRPCSEC_GSS認証で送信されるたびに、クライアントはGSSターゲットのプリンシパル名を注います。Exchange_IDの結果がクライアントIDのトランキングが可能で、GSSターゲットの「プリンシパル名は同じである場合は、サーバーは同じでクライアントIDのトランキングが許可されています。

The second option for verification is to use SP4_SSV protection. When the client sends EXCHANGE_ID, it specifies SP4_SSV protection. The first EXCHANGE_ID the client sends always has to be confirmed by a CREATE_SESSION call. The client then sends SET_SSV. Later, the client sends EXCHANGE_ID to a second destination network address different from the one the first EXCHANGE_ID was sent to. The client checks that each EXCHANGE_ID reply has the same eir_clientid, eir_server_owner.so_major_id, and eir_server_scope. If so, the client verifies the claim by sending a CREATE_SESSION operation to the second destination address, protected with RPCSEC_GSS integrity using an RPCSEC_GSS handle returned by the second EXCHANGE_ID. If the server accepts the CREATE_SESSION request, and if the client verifies the RPCSEC_GSS verifier and integrity codes, then the client has proof the second server knows the SSV, and thus the two servers are cooperating for the purposes of specifying server scope and client ID trunking.

検証のための2番目のオプションはSP4_SSV保護を使用することです。クライアントがExchange_IDを送信すると、SP4_SSV保護を指定します。最初のExchange_idクライアントの送信は常にCreate_Session呼び出しによって確認されなければなりません。その後、クライアントはset_ssvを送信します。後で、クライアントは、最初のExchange_IDが送信されたものとは異なる2番目の宛先ネットワークアドレスにExchange_idを送信します。クライアントは、各Exchange_ID応答に同じEIR_CLIENTID、EIR_SERVER_OWNER.SO_MAJOR_ID、EIR_SERVER_SCOPEがあることを確認します。もしそうであれば、クライアントは、2番目のExchange_IDによって返されるRPCSEC_GSSハンドルを使用して、RPCSEC_GSSの整合性を使用して保護された、CREATE_SESSION操作を2番目の宛先アドレスに送信することによってクレームを検証します。サーバーがcreate_session要求を受け入れ、クライアントがRPCSEC_GSS VerifierとIntegrityコードを検証した場合、クライアントは2番目のサーバーがSSVを認識しているため、サーバースコープとクライアントIDのトランキングを指定する目的で2つのサーバーが協力しています。 。

2.10.6. Exactly Once Semantics
2.10.6. 一度だけ意味:

Via the session, NFSv4.1 offers exactly once semantics (EOS) for requests sent over a channel. EOS is supported on both the fore channel and backchannel.


Each COMPOUND or CB_COMPOUND request that is sent with a leading SEQUENCE or CB_SEQUENCE operation MUST be executed by the receiver exactly once. This requirement holds regardless of whether the request is sent with reply caching specified (see Section The requirement holds even if the requester is sending the request over a session created between a pNFS data client and pNFS data server. To understand the rationale for this requirement, divide the requests into three classifications:


* Non-idempotent requests.


* Idempotent modifying requests.

* IDEmpotentの変更要求

* Idempotent non-modifying requests.

* IDEmpotent非修正要求

An example of a non-idempotent request is RENAME. Obviously, if a replier executes the same RENAME request twice, and the first execution succeeds, the re-execution will fail. If the replier returns the result from the re-execution, this result is incorrect. Therefore, EOS is required for non-idempotent requests.


An example of an idempotent modifying request is a COMPOUND request containing a WRITE operation. Repeated execution of the same WRITE has the same effect as execution of that WRITE a single time. Nevertheless, enforcing EOS for WRITEs and other idempotent modifying requests is necessary to avoid data corruption.


Suppose a client sends WRITE A to a noncompliant server that does not enforce EOS, and receives no response, perhaps due to a network partition. The client reconnects to the server and re-sends WRITE A. Now, the server has outstanding two instances of A. The server can be in a situation in which it executes and replies to the retry of A, while the first A is still waiting in the server's internal I/O system for some resource. Upon receiving the reply to the second attempt of WRITE A, the client believes its WRITE is done so it is free to send WRITE B, which overlaps the byte-range of A. When the original A is dispatched from the server's I/O system and executed (thus the second time A will have been written), then what has been written by B can be overwritten and thus corrupted.

クライアントがEOSを強制しない非コンポーネントのサーバーにWRITE Aを送信し、おそらくネットワークパーティションのために応答を受信しないとします。クライアントはサーバーに再接続し、Write Aを再送信します。これでサーバーの2つのインスタンスがあります。サーバーは、最初のAがまだ待っていますが、サーバーはAの再試行に応答して返信することができます。リソースのサーバーの内部I / Oシステムで。WRITE Aの2回目の試行への返信を受信すると、クライアントはその書き込みが行われるため、Aのバイト範囲を重複するのは自由に送信することができます。元のAがサーバーのI / Oシステムから送出されるときそして実行された(したがって、2番目の時間Aは書き込まれた)、Bによって書き込まれたものは上書きされ、したがって破損することができる。

An example of an idempotent non-modifying request is a COMPOUND containing SEQUENCE, PUTFH, READLINK, and nothing else. The re-execution of such a request will not cause data corruption or produce an incorrect result. Nonetheless, to keep the implementation simple, the replier MUST enforce EOS for all requests, whether or not idempotent and non-modifying.


Note that true and complete EOS is not possible unless the server persists the reply cache in stable storage, and unless the server is somehow implemented to never require a restart (indeed, if such a server exists, the distinction between a reply cache kept in stable storage versus one that is not is one without meaning). See Section for a discussion of persistence in the reply cache. Regardless, even if the server does not persist the reply cache, EOS improves robustness and correctness over previous versions of NFS because the legacy duplicate request/reply caches were based on the ONC RPC transaction identifier (XID). Section explains the shortcomings of the XID as a basis for a reply cache and describes how NFSv4.1 sessions improve upon the XID.

サーバーが安定したストレージ内の応答キャッシュを持続しない限り、TRUEと完全なEOSは不可能で、サーバーが再起動を必要としないように実行されていない限り(実際にはそのようなサーバーが存在する場合は、返信キャッシュの間の区別が安定して保持します。保存対1つは意味なしのものではありません)。返信キャッシュの永続性についての議論については、項を参照してください。とにかく、サーバが返信キャッシュを永続化しなくても、EOSは以前のバージョンのNFSに対する堅牢性と正確性を改善し、従来の重複リクエスト/返信キャッシュはONC RPCトランザクション識別子(XID)に基づいていました。セクション2.10.6.1は、返信キャッシュの基礎としてのXIDの欠点を説明し、NFSV4.1セッションがXIDを改善する方法を説明しています。 Slot Identifiers and Reply Cache スロット識別子と返信キャッシュ

The RPC layer provides a transaction ID (XID), which, while required to be unique, is not convenient for tracking requests for two reasons. First, the XID is only meaningful to the requester; it cannot be interpreted by the replier except to test for equality with previously sent requests. When consulting an RPC-based duplicate request cache, the opaqueness of the XID requires a computationally expensive look up (often via a hash that includes XID and source address). NFSv4.1 requests use a non-opaque slot ID, which is an index into a slot table, which is far more efficient. Second, because RPC requests can be executed by the replier in any order, there is no bound on the number of requests that may be outstanding at any time. To achieve perfect EOS, using ONC RPC would require storing all replies in the reply cache. XIDs are 32 bits; storing over four billion (2^(32)) replies in the reply cache is not practical. In practice, previous versions of NFS have chosen to store a fixed number of replies in the cache, and to use a least recently used (LRU) approach to replacing cache entries with new entries when the cache is full. In NFSv4.1, the number of outstanding requests is bounded by the size of the slot table, and a sequence ID per slot is used to tell the replier when it is safe to delete a cached reply.

RPCレイヤーはトランザクションID(XID)を提供します。これは、一意であることが要求されている間に、2つの理由で要求を追跡するのに便利ではありません。まず、XIDは要求者にとってのみ意味があります。以前に送信された要求との平等のテストを除いて、絞り目によって解釈されることはできません。 RPCベースの重複リクエストキャッシュをコンサルティングするとき、XIDの不透明度は計算上高価なルックアップを必要とします(多くの場合、XIDと送信元アドレスを含むハッシュを介して)。 NFSV4.1要求は、スロットテーブルへのインデックスである非不透明スロットIDを使用します。これははるかに効率的です。第二に、RPC要求は任意の順序でレプリアによって実行されることができるので、いつでも未解決の要求の数にバインドされていない。完璧なEOSを達成するには、ONC RPCを使用すると、返信キャッシュ内のすべての応答を格納する必要があります。 XIDは32ビットです。返信キャッシュ内で4億を超える記憶(2 ^(32))応答は実用的ではありません。実際には、以前のバージョンのNFSは、キャッシュ内に固定数の応答を保存し、キャッシュがいっぱいのときにキャッシュエントリを新しいエントリと置き換えるために最近使用されている(LRU)アプローチを使用することを選択しました。 NFSV4.1では、未処理の要求の数はスロットテーブルのサイズによって制限され、スロットごとのシーケンスIDを使用してキャッシュされた応答を削除しても安全な場合はレプリアを伝えます。

In the NFSv4.1 reply cache, when the requester sends a new request, it selects a slot ID in the range 0..N, where N is the replier's current maximum slot ID granted to the requester on the session over which the request is to be sent. The value of N starts out as equal to ca_maxrequests - 1 (Section 18.36), but can be adjusted by the response to SEQUENCE or CB_SEQUENCE as described later in this section. The slot ID must be unused by any of the requests that the requester has already active on the session. "Unused" here means the requester has no outstanding request for that slot ID.

NFSV4.1応答キャッシュでは、リクエスタが新しい要求を送信すると、0.nの範囲内のスロットIDを選択します。ここで、Nは、リクエストが要求されているセッションのリクエスタの現在の最大スロットIDです。送られる。nの値はCA_MAXRequests - 1と等しく始まります(セクション18.36)は、このセクションの後述のシーケンスまたはCB_Sequenceへの応答によって調整できます。スロットIDは、リクエスタがセッションですでにアクティブになっている要求のいずれかによって未使用でなければなりません。ここで「未使用」とは、要求者にそのスロットIDに対する未処理の要求がないことを意味します。

A slot contains a sequence ID and the cached reply corresponding to the request sent with that sequence ID. The sequence ID is a 32-bit unsigned value, and is therefore in the range 0..0xFFFFFFFF (2^(32) - 1). The first time a slot is used, the requester MUST specify a sequence ID of one (Section 18.36). Each time a slot is reused, the request MUST specify a sequence ID that is one greater than that of the previous request on the slot. If the previous sequence ID was 0xFFFFFFFF, then the next request for the slot MUST have the sequence ID set to zero (i.e., (2^(32) - 1) + 1 mod 2^(32)).

スロットはシーケンスIDとそのシーケンスIDで送信された要求に対応するキャッシュされた応答を含みます。シーケンスIDは32ビットの符号なし値であり、したがって0.0xFFFFFFFF(2 ^(32) - 1)の範囲内である。スロットが初めて使用されるとき、要求者は1のシーケンスIDを指定する必要があります(セクション18.36)。スロットが再利用されるたびに、リクエストはスロット上の前の要求の1つ以上のシーケンスIDを指定する必要があります。前のシーケンスIDが0xFFFFFFFFの場合、スロットに対する次の要求はゼロに設定されている(すなわち、(2 ^(32))1 MOD 2 ^(32))に設定されなければならない。

The sequence ID accompanies the slot ID in each request. It is for the critical check at the replier: it used to efficiently determine whether a request using a certain slot ID is a retransmit or a new, never-before-seen request. It is not feasible for the requester to assert that it is retransmitting to implement this, because for any given request the requester cannot know whether the replier has seen it unless the replier actually replies. Of course, if the requester has seen the reply, the requester would not retransmit.


The replier compares each received request's sequence ID with the last one previously received for that slot ID, to see if the new request is:


* A new request, in which the sequence ID is one greater than that previously seen in the slot (accounting for sequence wraparound). The replier proceeds to execute the new request, and the replier MUST increase the slot's sequence ID by one.

* シーケンスIDがスロットで前回見たものより1つ多い新しい要求(シーケンスラップアラウンドの会計)。REPLIERは新しい要求の実行に進み、レプリアはスロットのシーケンスIDを1つずつ増やす必要があります。

* A retransmitted request, in which the sequence ID is equal to that currently recorded in the slot. If the original request has executed to completion, the replier returns the cached reply. See Section for direction on how the replier deals with retries of requests that are still in progress.

* シーケンスIDが現在スロットに記録されているものと等しい再送信要求。元の要求が完了した場合、Replierはキャッシュされた応答を返します。セクションを参照してください。レプリアがまだ進行中の要求の再試行を扱う方法についての方向については、「」を参照してください。

* A misordered retry, in which the sequence ID is less than (accounting for sequence wraparound) that previously seen in the slot. The replier MUST return NFS4ERR_SEQ_MISORDERED (as the result from SEQUENCE or CB_SEQUENCE).

* シーケンスIDが以前にスロット内で前に見られた(シーケンスラップアラウンドの会計処理)より小さい誤った再試行。REPLIERはNFS4ERR_SEQ_MISORDERED(結果として(シーケンスまたはCB_SEQUENCE)を返す必要があります。

* A misordered new request, in which the sequence ID is two or more than (accounting for sequence wraparound) that previously seen in the slot. Note that because the sequence ID MUST wrap around to zero once it reaches 0xFFFFFFFF, a misordered new request and a misordered retry cannot be distinguished. Thus, the replier MUST return NFS4ERR_SEQ_MISORDERED (as the result from SEQUENCE or CB_SEQUENCE).

* シーケンスIDが、スロット内で以前に見られた(シーケンスラップアラウンドの会計処理)2以上の誤った新しい要求。シーケンスIDは、0xFFFFFFFFに達すると、誤って命令された新しい要求と誤ったリトライを区別することはできません。したがって、レプリタはNFS4ERR_SEQ_MISORDERED(結果として(シーケンスまたはCB_SEQUENCE)を返す必要があります。

Unlike the XID, the slot ID is always within a specific range; this has two implications. The first implication is that for a given session, the replier need only cache the results of a limited number of COMPOUND requests. The second implication derives from the first, which is that unlike XID-indexed reply caches (also known as duplicate request caches - DRCs), the slot ID-based reply cache cannot be overflowed. Through use of the sequence ID to identify retransmitted requests, the replier does not need to actually cache the request itself, reducing the storage requirements of the reply cache further. These facilities make it practical to maintain all the required entries for an effective reply cache.

XIDとは異なり、スロットIDは常に特定の範囲内です。これには2つの意味があります。第1の意味は、特定のセッションの場合、レプリアは限られた数の複合要求の結果をキャッシュするだけであることである。2番目の含意は最初から派生します。これは、XIDインデックス付きの返信キャッシュとは異なり(重複する要求キャッシュ - DRCとも呼ばれます)、スロットIDベースの応答キャッシュをオーバーフローすることはできません。再送信要求を識別するためにシーケンスIDを使用することで、レプリタは要求自体を実際にキャッシュする必要はなく、返信キャッシュのストレージ要件をさらに短縮する必要はありません。これらの施設は、効果的な返信キャッシュのすべての必要なエントリを維持することを実用的にします。

The slot ID, sequence ID, and session ID therefore take over the traditional role of the XID and source network address in the replier's reply cache implementation. This approach is considerably more portable and completely robust -- it is not subject to the reassignment of ports as clients reconnect over IP networks. In addition, the RPC XID is not used in the reply cache, enhancing robustness of the cache in the face of any rapid reuse of XIDs by the requester. While the replier does not care about the XID for the purposes of reply cache management (but the replier MUST return the same XID that was in the request), nonetheless there are considerations for the XID in NFSv4.1 that are the same as all other previous versions of NFS. The RPC XID remains in each message and needs to be formulated in NFSv4.1 requests as in any other ONC RPC request. The reasons include:

したがって、スロットID、シーケンスID、およびセッションIDは、レプリタの応答キャッシュ実装内のXIDおよびソースネットワークアドレスの従来の役割を引き継ぎます。このアプローチはかなりポータブルで完全に堅牢です。クライアントがIPネットワークを介して再接続されているため、ポートの再割り当てが受けられません。さらに、RPC XIDは応答キャッシュでは使用されず、リクエスターによるXIDの迅速な再利用の範囲内のキャッシュの堅牢性を高めます。Replier Cache Managementの目的のためにXIDを気にしない間(ただし、リクエストが要求されていた同じXIDを返す必要があります)。それにもかかわらず、他のすべてと同じであるNFSv4.1のXIDに関する考慮事項があります。以前のバージョンのNFS。RPC XIDは各メッセージに残り、他のONC RPC要求のようにNFSv4.1要求に定式化する必要があります。その理由は次のとおりです。

* The RPC layer retains its existing semantics and implementation.

* RPC層は既存の意味と実装を保持しています。

* The requester and replier must be able to interoperate at the RPC layer, prior to the NFSv4.1 decoding of the SEQUENCE or CB_SEQUENCE operation.

* リクエスターとレプリタは、シーケンスまたはCB_SEQUENCE動作のNFSV4.1の復号化の前に、RPCレイヤーで相互運用できる必要があります。

* If an operation is being used that does not start with SEQUENCE or CB_SEQUENCE (e.g., BIND_CONN_TO_SESSION), then the RPC XID is needed for correct operation to match the reply to the request.

* シーケンスまたはCB_SEQUENCE(例えば、bind_conn_to_session)で始まらない操作が使用されている場合、RPC XIDは要求への応答と一致するように正しい操作のために必要です。

* The SEQUENCE or CB_SEQUENCE operation may generate an error. If so, the embedded slot ID, sequence ID, and session ID (if present) in the request will not be in the reply, and the requester has only the XID to match the reply to the request.

* シーケンスまたはCB_Sequenceの動作はエラーを生成する可能性があります。もしそうであれば、リクエスト内の埋め込みスロットID、シーケンスID、およびセッションID(存在する場合)は返信に含まれず、要求に応答に合わせるためのXIDのみがあります。

Given that well-formulated XIDs continue to be required, this raises the question: why do SEQUENCE and CB_SEQUENCE replies have a session ID, slot ID, and sequence ID? Having the session ID in the reply means that the requester does not have to use the XID to look up the session ID, which would be necessary if the connection were associated with multiple sessions. Having the slot ID and sequence ID in the reply means that the requester does not have to use the XID to look up the slot ID and sequence ID. Furthermore, since the XID is only 32 bits, it is too small to guarantee the re-association of a reply with its request [44]; having session ID, slot ID, and sequence ID in the reply allows the client to validate that the reply in fact belongs to the matched request.


The SEQUENCE (and CB_SEQUENCE) operation also carries a "highest_slotid" value, which carries additional requester slot usage information. The requester MUST always indicate the slot ID representing the outstanding request with the highest-numbered slot value. The requester should in all cases provide the most conservative value possible, although it can be increased somewhat above the actual instantaneous usage to maintain some minimum or optimal level. This provides a way for the requester to yield unused request slots back to the replier, which in turn can use the information to reallocate resources.


The replier responds with both a new target highest_slotid and an enforced highest_slotid, described as follows:

replierは、次のように説明されている新しいターゲットのimpslotidとentoced hisspslotidの両方で応答します。

* The target highest_slotid is an indication to the requester of the highest_slotid the replier wishes the requester to be using. This permits the replier to withdraw (or add) resources from a requester that has been found to not be using them, in order to more fairly share resources among a varying level of demand from other requesters. The requester must always comply with the replier's value updates, since they indicate newly established hard limits on the requester's access to session resources. However, because of request pipelining, the requester may have active requests in flight reflecting prior values; therefore, the replier must not immediately require the requester to comply.

* ターゲットhiste_slotidは、replicierが要求者に使用する希望者が求められているrequest_lotidの要求者への指示です。これにより、他のリクエスタからさまざまなレベルの需要の間でリソースをより公正に共有するために、それらを使用していないことが判明したリクエスターからリソースを撤回する(または追加)リソースを引き出す(または追加)リソースを引き出すことができます。リクエスタのセッションリソースへのアクセス権に対して新しく確立されたハードリミットを示すので、リクエスターは常にレプリアの値の更新に準拠している必要があります。しかしながら、リクエストパイプライン化のために、要求者は事前の値を反映して有効な要求を有することができる。したがって、レプリタはすぐに要求者に準拠する必要がありません。

* The enforced highest_slotid indicates the highest slot ID the requester is permitted to use on a subsequent SEQUENCE or CB_SEQUENCE operation. The replier's enforced highest_slotid SHOULD be no less than the highest_slotid the requester indicated in the SEQUENCE or CB_SEQUENCE arguments.

* 施行されたhist_slotidは、最上位のスロットIDを示しています。要求者は、後続のシーケンスまたはCB_Sequence操作で使用できます。replierの強制されたhiss_slotidは、sequenceまたはcb_sequence引数に示されている要求者がhists_slotidを下回る必要があります。

A requester can be intransigent with respect to lowering its highest_slotid argument to a Sequence operation, i.e. the requester continues to ignore the target highest_slotid in the response to a Sequence operation, and continues to set its highest_slotid argument to be higher than the target highest_slotid. This can be considered particularly egregious behavior when the replier knows there are no outstanding requests with slot IDs higher than its target highest_slotid. When faced with such intransigence, the replier is free to take more forceful action, and MAY reply with a new enforced highest_slotid that is less than its previous enforced highest_slotid. Thereafter, if the requester continues to send requests with a highest_slotid that is greater than the replier's new enforced highest_slotid, the server MAY return NFS4ERR_BAD_HIGH_SLOT, unless the slot ID in the request is greater than the new enforced highest_slotid and the request is a retry.


The replier SHOULD retain the slots it wants to retire until the requester sends a request with a highest_slotid less than or equal to the replier's new enforced highest_slotid.


The requester can also be intransigent with respect to sending non-retry requests that have a slot ID that exceeds the replier's highest_slotid. Once the replier has forcibly lowered the enforced highest_slotid, the requester is only allowed to send retries on slots that exceed the replier's highest_slotid. If a request is received with a slot ID that is higher than the new enforced highest_slotid, and the sequence ID is one higher than what is in the slot's reply cache, then the server can both retire the slot and return NFS4ERR_BADSLOT (however, the server MUST NOT do one and not the other). The reason it is safe to retire the slot is because by using the next sequence ID, the requester is indicating it has received the previous reply for the slot.


* The requester SHOULD use the lowest available slot when sending a new request. This way, the replier may be able to retire slot entries faster. However, where the replier is actively adjusting its granted highest_slotid, it will not be able to use only the receipt of the slot ID and highest_slotid in the request. Neither the slot ID nor the highest_slotid used in a request may reflect the replier's current idea of the requester's session limit, because the request may have been sent from the requester before the update was received. Therefore, in the downward adjustment case, the replier may have to retain a number of reply cache entries at least as large as the old value of maximum requests outstanding, until it can infer that the requester has seen a reply containing the new granted highest_slotid. The replier can infer that the requester has seen such a reply when it receives a new request with the same slot ID as the request replied to and the next higher sequence ID.

* リクエスタは、新しい要求を送信するときに最も低いスロットを使用する必要があります。このようにして、レプリアはスロットエントリをより速く遅らせることができるかもしれません。ただし、レプリアが積極的に付与されているISTIS_SLOTIDを積極的に調整している場合は、リクエスト内のスロットIDとSLOTIDの受信のみを使用できません。リクエストで使用されているスロットIDもSLOT_SLOTIDも、更新が受信される前にリクエスタから送信された可能性があるため、リクエスタのセッション制限のリクエストの現在のアイデアを反映しています。したがって、下向き調整ケースでは、リクエスタが未処理の最大要求の古い値と同じくらい大きなリクエストの古い値と同じくらい大きな応答キャッシュエントリを、依存していると推測されるまで、要求者が新しいArgited_SLOTIDを含む返信を見たことができる。リプライアは、リクエストがリクエストと同じスロットIDを持つ新しい要求を受信したとき、および次の高いシーケンスIDを持つ新しい要求を受信したときに、要求者がそのような応答を見たことを推測できます。 Caching of SEQUENCE and CB_SEQUENCE Replies シーケンスとCB_Sequenceのキャッシング

When a SEQUENCE or CB_SEQUENCE operation is successfully executed, its reply MUST always be cached. Specifically, session ID, sequence ID, and slot ID MUST be cached in the reply cache. The reply from SEQUENCE also includes the highest slot ID, target highest slot ID, and status flags. Instead of caching these values, the server MAY re-compute the values from the current state of the fore channel, session, and/or client ID as appropriate. Similarly, the reply from CB_SEQUENCE includes a highest slot ID and target highest slot ID. The client MAY re-compute the values from the current state of the session as appropriate.


Regardless of whether or not a replier is re-computing highest slot ID, target slot ID, and status on replies to retries, the requester MUST NOT assume that the values are being re-computed whenever it receives a reply after a retry is sent, since it has no way of knowing whether the reply it has received was sent by the replier in response to the retry or is a delayed response to the original request. Therefore, it may be the case that highest slot ID, target slot ID, or status bits may reflect the state of affairs when the request was first executed. Although acting based on such delayed information is valid, it may cause the receiver of the reply to do unneeded work. Requesters MAY choose to send additional requests to get the current state of affairs or use the state of affairs reported by subsequent requests, in preference to acting immediately on data that might be out of date.

Replierが最も高いスロットID、ターゲットスロットID、およびレプリブのステータスを再計算しているかどうかにかかわらず、リクエスタは再試行が送信された後に返信を受け取るたびに値が再計算されていると想定してはなりません。再試行に応答して受信した返信が再試行者によって送信されたかどうかを知らないので、元の要求に対する遅延応答である。したがって、要求が最初に実行されたときに、最も高いスロットID、対象スロットID、またはステータスビットが事態を反映している場合がある。そのような遅延情報に基づく作用は有効であるが、返信の受信者が不要な作業をする可能性がある。リクエスタは、現在の状況を取得するため、または後続の要求によって報告された状況を使用して、最新の要求によって報告されている状況を使用することを選択します。 Errors from SEQUENCE and CB_SEQUENCE シーケンスとCB_Sequenceからのエラー

Any time SEQUENCE or CB_SEQUENCE returns an error, the sequence ID of the slot MUST NOT change. The replier MUST NOT modify the reply cache entry for the slot whenever an error is returned from SEQUENCE or CB_SEQUENCE.

任意の時系列またはCB_Sequenceはエラーを返し、スロットのシーケンスIDは変更してはなりません。replierは、エラーがシーケンスまたはCB_Sequenceから返されるたびに、スロットの応答キャッシュエントリを変更してはいけません。 Optional Reply Caching オプションの返信キャッシング

On a per-request basis, the requester can choose to direct the replier to cache the reply to all operations after the first operation (SEQUENCE or CB_SEQUENCE) via the sa_cachethis or csa_cachethis fields of the arguments to SEQUENCE or CB_SEQUENCE. The reason it would not direct the replier to cache the entire reply is that the request is composed of all idempotent operations [41]. Caching the reply may offer little benefit. If the reply is too large (see Section, it may not be cacheable anyway. Even if the reply to idempotent request is small enough to cache, unnecessarily caching the reply slows down the server and increases RPC latency.


Whether or not the requester requests the reply to be cached has no effect on the slot processing. If the result of SEQUENCE or CB_SEQUENCE is NFS4_OK, then the slot's sequence ID MUST be incremented by one. If a requester does not direct the replier to cache the reply, the replier MUST do one of following:


* The replier can cache the entire original reply. Even though sa_cachethis or csa_cachethis is FALSE, the replier is always free to cache. It may choose this approach in order to simplify implementation.

* replierは元の返信全体をキャッシュできます。SA_CACHETHISまたはCSA_CACHETHISがfalseであっても、replierは常にキャッシュを自由にしています。実装を簡単にするためにこのアプローチを選択することができます。

* The replier enters into its reply cache a reply consisting of the original results to the SEQUENCE or CB_SEQUENCE operation, and with the next operation in COMPOUND or CB_COMPOUND having the error NFS4ERR_RETRY_UNCACHED_REP. Thus, if the requester later retries the request, it will get NFS4ERR_RETRY_UNCACHED_REP. If a replier receives a retried Sequence operation where the reply to the COMPOUND or CB_COMPOUND was not cached, then the replier,

* レプリアは、その応答キャッシュに、元の結果からシーケンスまたはCB_Sequence操作、およびエラーNFS4ERR_RETRY_UNCACHED_REPを有する化合物またはCB_COMPOUNDでの次の操作で返信キャッシュをキャッシュに入ります。したがって、要求者が後で要求を再試行すると、NFS4ERR_RETRY_UNCACHED_REPが得られます。リプライアが複製シーケンス操作を受信した場合、複合またはcb_compoundへの応答がキャッシュされていない場合は、

- MAY return NFS4ERR_RETRY_UNCACHED_REP in reply to a Sequence operation if the Sequence operation is not the first operation (granted, a requester that does so is in violation of the NFSv4.1 protocol).

- シーケンス操作が最初の操作ではない場合は、シーケンス操作に応答してNFS4ERR_RETRY_UNCACHED_REPを返します(許可されている要求者は、NFSV4.1プロトコルに違反しているリクエスター)。

- MUST NOT return NFS4ERR_RETRY_UNCACHED_REP in reply to a Sequence operation if the Sequence operation is the first operation.

- シーケンス操作が最初の操作である場合、シーケンス操作に応答してNFS4ERR_RETRY_UNCACHED_REPを返してはなりません。

* If the second operation is an illegal operation, or an operation that was legal in a previous minor version of NFSv4 and MUST NOT be supported in the current minor version (e.g., SETCLIENTID), the replier MUST NOT ever return NFS4ERR_RETRY_UNCACHED_REP. Instead the replier MUST return NFS4ERR_OP_ILLEGAL or NFS4ERR_BADXDR or NFS4ERR_NOTSUPP as appropriate.

* 2番目の操作が不正な操作である場合、または以前のマイナーバージョンのNFSV4で正当な操作で、現在のマイナーバージョン(例えばSetClientID)でサポートされていなければならない場合は、ReplierがNFS4ERR_RETRY_UNCACHED_REPを返さないようにしてください。代わりに、必要に応じて、replierはNFS4ERR_OP_ILLEGALまたはNFS4ERR_BADXDRまたはNFS4ERR_NOTSUPPを返す必要があります。

* If the second operation can result in another error status, the replier MAY return a status other than NFS4ERR_RETRY_UNCACHED_REP, provided the operation is not executed in such a way that the state of the replier is changed. Examples of such an error status include: NFS4ERR_NOTSUPP returned for an operation that is legal but not REQUIRED in the current minor versions, and thus not supported by the replier; NFS4ERR_SEQUENCE_POS; and NFS4ERR_REQ_TOO_BIG.

* 第2の操作が別のエラー状態になる可能性がある場合、レプリアの状態が変更されるように操作が実行されない場合には、ReplierがNFS4ERR_RETRY_UNCACHED_REPを返すことができる。このようなエラーステータスの例は次のとおりです.nfs4err_notsuppは、正当な操作に対して返され、現在のマイナーバージョンでは必須ではなく、したがってレプリアによってサポートされていません。NFS4ERR_SEQUENCE_POS;NFS4ERR_REQ_TOO_BIG。

The discussion above assumes that the retried request matches the original one. Section discusses what the replier might do, and MUST do when original and retried requests do not match. Since the replier may only cache a small amount of the information that would be required to determine whether this is a case of a false retry, the replier may send to the client any of the following responses:


* The cached reply to the original request (if the replier has cached it in its entirety and the users of the original request and retry match).

* 元のリクエストへのキャッシュされた返信(レプリアが全体としてキャッシュした場合、元の要求と再試行のユーザにキャッシュした場合)。

* A reply that consists only of the Sequence operation with the error NFS4ERR_SEQ_FALSE_RETRY.

* エラーNFS4ERR_SEQ_FALSE_RETRYを使用してシーケンス操作のみで構成されている応答。

* A reply consisting of the response to Sequence with the status NFS4_OK, together with the second operation as it appeared in the retried request with an error of NFS4ERR_RETRY_UNCACHED_REP or other error as described above.

* NFS4ERR_RETRY_UNCACHED_REPまたはその他のエラーのエラーを誤りに登録されているときに、ステータスNFS4_OKとの応答からの応答と、上述のようにして実行された応答からなる。

* A reply that consists of the response to Sequence with the status NFS4_OK, together with the second operation as it appeared in the original request with an error of NFS4ERR_RETRY_UNCACHED_REP or other error as described above.

* NFS4ERR_RETRY_UNCACHED_REPまたはその他のエラーのエラーを持つ、NFS4ERR_RETRY_UNCACHED_REPまたはその他のエラーのエラーを持つ最初の要求に登場したときの、ステータスNFS4_OKとの応答からの応答で構成されています。 False Retry 誤った再試行

If a requester sent a Sequence operation with a slot ID and sequence ID that are in the reply cache but the replier detected that the retried request is not the same as the original request, including a retry that has different operations or different arguments in the operations from the original and a retry that uses a different principal in the RPC request's credential field that translates to a different user, then this is a false retry. When the replier detects a false retry, it is permitted (but not always obligated) to return NFS4ERR_SEQ_FALSE_RETRY in response to the Sequence operation when it detects a false retry.


Translations of particularly privileged user values to other users due to the lack of appropriately secure credentials, as configured on the replier, should be applied before determining whether the users are the same or different. If the replier determines the users are different between the original request and a retry, then the replier MUST return NFS4ERR_SEQ_FALSE_RETRY.


If an operation of the retry is an illegal operation, or an operation that was legal in a previous minor version of NFSv4 and MUST NOT be supported in the current minor version (e.g., SETCLIENTID), the replier MAY return NFS4ERR_SEQ_FALSE_RETRY (and MUST do so if the users of the original request and retry differ). Otherwise, the replier MAY return NFS4ERR_OP_ILLEGAL or NFS4ERR_BADXDR or NFS4ERR_NOTSUPP as appropriate. Note that the handling is in contrast for how the replier deals with retries requests with no cached reply. The difference is due to NFS4ERR_SEQ_FALSE_RETRY being a valid error for only Sequence operations, whereas NFS4ERR_RETRY_UNCACHED_REP is a valid error for all operations except illegal operations and operations that MUST NOT be supported in the current minor version of NFSv4.

再試行の操作が不正な操作、または以前のマイナーバージョンのNFSV4で正当な操作で、現在のマイナーバージョン(SetClientID)ではサポートされてはならない操作であれば、ReplierはNFS4ERR_SEQ_FALSE_RETRYを返すことができます(そしてそうしなければならない元の要求のユーザーが異なる場合)それ以外の場合、レプリタは必要に応じてNFS4ERR_OP_ILLEGALまたはNFS4ERR_BADXDRまたはNFS4ERR_NOTSUPPを返すことがあります。リプライアがリトライを取得する方法は、キャッシュされた返信のない要求にどのように取引されるかについては、処理が対照的です。この違いは、NFS4ERR_SEQ_FALSE_RETRYのみがシーケンス操作のみの有効なエラーであるため、NFS4ERR_RETRY_UNCACHED_REPは、NFSV4の現在のマイナーバージョンでサポートされていなければならない違法な操作と操作を除くすべての操作の有効なエラーです。 Retry and Replay of Reply 返信を再試行して再生します

A requester MUST NOT retry a request, unless the connection it used to send the request disconnects. The requester can then reconnect and re-send the request, or it can re-send the request over a different connection that is associated with the same session.


If the requester is a server wanting to re-send a callback operation over the backchannel of a session, the requester of course cannot reconnect because only the client can associate connections with the backchannel. The server can re-send the request over another connection that is bound to the same session's backchannel. If there is no such connection, the server MUST indicate that the session has no backchannel by setting the SEQ4_STATUS_CB_PATH_DOWN_SESSION flag bit in the response to the next SEQUENCE operation from the client. The client MUST then associate a connection with the session (or destroy the session).


Note that it is not fatal for a requester to retry without a disconnect between the request and retry. However, the retry does consume resources, especially with RDMA, where each request, retry or not, consumes a credit. Retries for no reason, especially retries sent shortly after the previous attempt, are a poor use of network bandwidth and defeat the purpose of a transport's inherent congestion control system.


A requester MUST wait for a reply to a request before using the slot for another request. If it does not wait for a reply, then the requester does not know what sequence ID to use for the slot on its next request. For example, suppose a requester sends a request with sequence ID 1, and does not wait for the response. The next time it uses the slot, it sends the new request with sequence ID 2. If the replier has not seen the request with sequence ID 1, then the replier is not expecting sequence ID 2, and rejects the requester's new request with NFS4ERR_SEQ_MISORDERED (as the result from SEQUENCE or CB_SEQUENCE).

要求者は、スロットを別の要求に使用する前に要求への返信を待つ必要があります。返信を待っていない場合、リクエスターは次の要求のスロットに使用するシーケンスIDを知りません。たとえば、リクエスターがシーケンスID 1で要求を送信し、応答を待っていないとします。次回スロットを使用するときは、シーケンスID 2で新しい要求を送信します。レプリアがシーケンスID 1の要求を見ていない場合は、レプリアはシーケンスID 2を期待していないため、NFS4ER_SEQ_MISORDERDED(シーケンスまたはCB_Sequenceの結果として。

RDMA fabrics do not guarantee that the memory handles (Steering Tags) within each RPC/RDMA "chunk" [32] are valid on a scope outside that of a single connection. Therefore, handles used by the direct operations become invalid after connection loss. The server must ensure that any RDMA operations that must be replayed from the reply cache use the newly provided handle(s) from the most recent request.

RDMAファブリックは、各RPC / RDMA "チャンク" [32]内のメモリハンドル(ステアリングタグ)が単一の接続の外側の範囲で有効であることを保証しません。したがって、接続損失後に直接操作で使用されるハンドルが無効になります。サーバーは、返信キャッシュから再生する必要があるRDMA操作が、最新の要求から新しく提供されたハンドルを使用していることを確認する必要があります。

A retry might be sent while the original request is still in progress on the replier. The replier SHOULD deal with the issue by returning NFS4ERR_DELAY as the reply to SEQUENCE or CB_SEQUENCE operation, but implementations MAY return NFS4ERR_MISORDERED. Since errors from SEQUENCE and CB_SEQUENCE are never recorded in the reply cache, this approach allows the results of the execution of the original request to be properly recorded in the reply cache (assuming that the requester specified the reply to be cached).

元の要求が依然として再スポードで進行中の間に再試行が送信されることがあります。replierは、SequenceまたはCB_Sequence操作への返信としてNFS4ERR_DELAYを返すことによって問題に対処する必要がありますが、実装はNFS4ERR_MISORDEREDを返すことがあります。シーケンスとCB_Sequenceからのエラーが返信キャッシュに記録されないため、元の要求の実行結果を返信キャッシュに適切に記録することができます(リクエスタがキャッシュされる応答を指定したと仮定する)。 Resolving Server Callback Races サーバーコールバックレースの解決

It is possible for server callbacks to arrive at the client before the reply from related fore channel operations. For example, a client may have been granted a delegation to a file it has opened, but the reply to the OPEN (informing the client of the granting of the delegation) may be delayed in the network. If a conflicting operation arrives at the server, it will recall the delegation using the backchannel, which may be on a different transport connection, perhaps even a different network, or even a different session associated with the same client ID.


The presence of a session between the client and server alleviates this issue. When a session is in place, each client request is uniquely identified by its { session ID, slot ID, sequence ID } triple. By the rules under which slot entries (reply cache entries) are retired, the server has knowledge whether the client has "seen" each of the server's replies. The server can therefore provide sufficient information to the client to allow it to disambiguate between an erroneous or conflicting callback race condition.


For each client operation that might result in some sort of server callback, the server SHOULD "remember" the { session ID, slot ID, sequence ID } triple of the client request until the slot ID retirement rules allow the server to determine that the client has, in fact, seen the server's reply. Until the time the { session ID, slot ID, sequence ID } request triple can be retired, any recalls of the associated object MUST carry an array of these referring identifiers (in the CB_SEQUENCE operation's arguments), for the benefit of the client. After this time, it is not necessary for the server to provide this information in related callbacks, since it is certain that a race condition can no longer occur.

ある種のサーバーコールバックをもたらす可能性がある各クライアント操作に対して、Slot IDの退除規則がサーバーがクライアントが決定できるようになるまで、クライアント要求の{セッションID、スロットID、シーケンスID}トリプルを「覚えておく」必要があります。実際には、サーバーの返信を見ました。{セッションID、スロットID、シーケンスID}リクエストトリプルを引退することができるまでに、関連付けられているオブジェクトのリコールは、クライアントの利点について、これらの参照識別子の配列を(CB_Sequence操作の引数)の配列を持たなければなりません。この時間の後、サーバーはレースの状態が発生しなくなることが確実であることが確実であるため、この情報を関連するコールバックに提供する必要はありません。

The CB_SEQUENCE operation that begins each server callback carries a list of "referring" { session ID, slot ID, sequence ID } triples. If the client finds the request corresponding to the referring session ID, slot ID, and sequence ID to be currently outstanding (i.e., the server's reply has not been seen by the client), it can determine that the callback has raced the reply, and act accordingly. If the client does not find the request corresponding to the referring triple to be outstanding (including the case of a session ID referring to a destroyed session), then there is no race with respect to this triple. The server SHOULD limit the referring triples to requests that refer to just those that apply to the objects referred to in the CB_COMPOUND procedure.


The client must not simply wait forever for the expected server reply to arrive before responding to the CB_COMPOUND that won the race, because it is possible that it will be delayed indefinitely. The client should assume the likely case that the reply will arrive within the average round-trip time for COMPOUND requests to the server, and wait that period of time. If that period of time expires, it can respond to the CB_COMPOUND with NFS4ERR_DELAY. There are other scenarios under which callbacks may race replies. Among them are pNFS layout recalls as described in Section

クライアントは、レースを獲得したCB_COMPOUNDに応答する前に、予想されるサーバーの応答が永遠に到着してはいけません。クライアントは、応答がサーバーへの複合要求の平均往復時間内に到着し、その期間を待つという可能性が高いと仮定する必要があります。その期間が期限切れになると、NFS4ERR_DELAYを使用してCB_COMPOUNDに応答できます。コールバックが答えを競技することがある他のシナリオもあります。その中には、PNFSレイアウトがセクション12.5.5.2で説明されているようにリコールされています。 COMPOUND and CB_COMPOUND Construction Issues 化合物とCB_COMPOUND構造の問題

Very large requests and replies may pose both buffer management issues (especially with RDMA) and reply cache issues. When the session is created (Section 18.36), for each channel (fore and back), the client and server negotiate the maximum-sized request they will send or process (ca_maxrequestsize), the maximum-sized reply they will return or process (ca_maxresponsesize), and the maximum-sized reply they will store in the reply cache (ca_maxresponsesize_cached).


If a request exceeds ca_maxrequestsize, the reply will have the status NFS4ERR_REQ_TOO_BIG. A replier MAY return NFS4ERR_REQ_TOO_BIG as the status for the first operation (SEQUENCE or CB_SEQUENCE) in the request (which means that no operations in the request executed and that the state of the slot in the reply cache is unchanged), or it MAY opt to return it on a subsequent operation in the same COMPOUND or CB_COMPOUND request (which means that at least one operation did execute and that the state of the slot in the reply cache does change). The replier SHOULD set NFS4ERR_REQ_TOO_BIG on the operation that exceeds ca_maxrequestsize.


If a reply exceeds ca_maxresponsesize, the reply will have the status NFS4ERR_REP_TOO_BIG. A replier MAY return NFS4ERR_REP_TOO_BIG as the status for the first operation (SEQUENCE or CB_SEQUENCE) in the request, or it MAY opt to return it on a subsequent operation (in the same COMPOUND or CB_COMPOUND reply). A replier MAY return NFS4ERR_REP_TOO_BIG in the reply to SEQUENCE or CB_SEQUENCE, even if the response would still exceed ca_maxresponsesize.

返信がCA_MAXResponseSizeを超えると、応答はステータスNFS4ERR_REP_TOO_BIGを持ちます。Replierは、要求内の最初の操作(シーケンスまたはCB_Sequence)のステータスとしてNFS4ERR_REP_TOO_BIGを返すか、またはそれを後続の操作(同じ化合物またはCB_COMPOUND REPLANDで)返すことを選択できます。応答が依然としてCA_MAXResponseSizeを超えていても、Replierが応答内のnfs4err_rep_too_bigをsequenceまたはcb_sequenceに返すことができます。

If sa_cachethis or csa_cachethis is TRUE, then the replier MUST cache a reply except if an error is returned by the SEQUENCE or CB_SEQUENCE operation (see Section If the reply exceeds ca_maxresponsesize_cached (and sa_cachethis or csa_cachethis is TRUE), then the server MUST return NFS4ERR_REP_TOO_BIG_TO_CACHE. Even if NFS4ERR_REP_TOO_BIG_TO_CACHE (or any other error for that matter) is returned on an operation other than the first operation (SEQUENCE or CB_SEQUENCE), then the reply MUST be cached if sa_cachethis or csa_cachethis is TRUE. For example, if a COMPOUND has eleven operations, including SEQUENCE, the fifth operation is a RENAME, and the tenth operation is a READ for one million bytes, the server may return NFS4ERR_REP_TOO_BIG_TO_CACHE on the tenth operation. Since the server executed several operations, especially the non-idempotent RENAME, the client's request to cache the reply needs to be honored in order for the correct operation of exactly once semantics. If the client retries the request, the server will have cached a reply that contains results for ten of the eleven requested operations, with the tenth operation having a status of NFS4ERR_REP_TOO_BIG_TO_CACHE.

SA_CACHETHISまたはCSA_CACHETHISがtrueの場合、レプリアはシーケンスまたはCB_Sequence操作によってエラーが返される場合を除き、応答をキャッシュする必要があります(セクション2.を参照)。返信がCA_MAXResponseSize_cached(およびSA_CachethisまたはCSA_Cachethisがtrue)を超えると、サーバーはNFS4ERR_REP_TOO_BIG_TO_TO_CACHEを返す必要があります。 NFS4ERR_REP_TOO_BIG_TO_CACHE(またはその重要なエラー)が最初の操作(シーケンスまたはCB_Sequence)以外の操作で返された場合でも、SA_CACHETHISまたはCSA_CACHETHISがTRUEの場合、返信をキャッシュする必要があります。たとえば、シーケンスを含めて、化合物が11の操作を持つ場合、5番目の操作は名前の変更であり、10回目の操作は100万バイトの読み取りです。サーバーは、サーバーは10回目の動作でNFS4R_REP_TOO_BIG_TO_CACHEを返すことがあります。サーバーはいくつかの操作、特にIDEMPOTENT NONAMEを実行したため、クライアントの返信をキャッシュする要求は、一度正確に正確に操作するために称わられる必要があります。クライアントが要求を再試行した場合、サーバーは11の要求された操作のうちの10の結果を含む応答をキャッシュしており、10番目の操作はNFS4ERR_REP_TOO_BIG_TO_TO_CACHEのステータスを持ちます。

A client needs to take care that, when sending operations that change the current filehandle (except for PUTFH, PUTPUBFH, PUTROOTFH, and RESTOREFH), it does not exceed the maximum reply buffer before the GETFH operation. Otherwise, the client will have to retry the operation that changed the current filehandle, in order to obtain the desired filehandle. For the OPEN operation (see Section 18.16), retry is not always available as an option. The following guidelines for the handling of filehandle-changing operations are advised:


* Within the same COMPOUND procedure, a client SHOULD send GETFH immediately after a current filehandle-changing operation. A client MUST send GETFH after a current filehandle-changing operation that is also non-idempotent (e.g., the OPEN operation), unless the operation is RESTOREFH. RESTOREFH is an exception, because even though it is non-idempotent, the filehandle RESTOREFH produced originated from an operation that is either idempotent (e.g., PUTFH, LOOKUP), or non-idempotent (e.g., OPEN, CREATE). If the origin is non-idempotent, then because the client MUST send GETFH after the origin operation, the client can recover if RESTOREFH returns an error.

* 同じ複合手順で、クライアントは現在のファイルハンドル変更操作の直後にGETFHを送信する必要があります。操作が復元されない限り、現在のファイルハンドル変更操作の後に、クライアントはGETFHを送信する必要があります(例えば、オープン操作)。RestoreFhは例外です。原点がIDEMPOTENTである場合、クライアントはOrigin操作の後にGETFHを送信する必要があるため、RESTOREFHがエラーを返す場合、クライアントは回復できます。

* A server MAY return NFS4ERR_REP_TOO_BIG or NFS4ERR_REP_TOO_BIG_TO_CACHE (if sa_cachethis is TRUE) on a filehandle-changing operation if the reply would be too large on the next operation.


* A server SHOULD return NFS4ERR_REP_TOO_BIG or NFS4ERR_REP_TOO_BIG_TO_CACHE (if sa_cachethis is TRUE) on a filehandle-changing, non-idempotent operation if the reply would be too large on the next operation, especially if the operation is OPEN.

* サーバーは、FileHandle-Changitedの場合、特に操作が開いている場合は、次の操作でリ応答が大きすぎる場合は、ファイルハンドル変更では、IDEMPOTENTのない操作で、サーバーがNFS4ERR_REP_TOO_BIGまたはNFS4ERR_REP_TOO_BIG_TO_CACHE(SA_CACHETHISがTRUE)を返す必要があります。

* A server MAY return NFS4ERR_UNSAFE_COMPOUND to a non-idempotent current filehandle-changing operation, if it looks at the next operation (in the same COMPOUND procedure) and finds it is not GETFH. The server SHOULD do this if it is unable to determine in advance whether the total response size would exceed ca_maxresponsesize_cached or ca_maxresponsesize.

* サーバーは、次の操作(同じ複合手順で)調べてGETFHではないと検索されている場合、NFS4ERR_UNSAFE_COMPOUNDを非IDEmPOTENT現在のファイルハンドル変更操作に戻すことができます。合計応答サイズがCA_MAXResponseSize_CachedまたはCA_MAXResponseSizeを超えるかどうかを事前に決定できない場合、サーバーはこれを行うべきです。 Persistence 永続的な

Since the reply cache is bounded, it is practical for the reply cache to persist across server restarts. The replier MUST persist the following information if it agreed to persist the session (when the session was created; see Section 18.36):

応答キャッシュは境界が付けられているので、応答キャッシュがサーバーの再起動を継続して持続するのが実用的です。セッションを永続化することに合意した場合(セッションが作成されたときに; 18.36を参照)。

* The session ID.

* セッションID。

* The slot table including the sequence ID and cached reply for each slot.

* 各スロットのシーケンスIDとキャッシュされた応答を含むスロットテーブル。

The above are sufficient for a replier to provide EOS semantics for any requests that were sent and executed before the server restarted. If the replier is a client, then there is no need for it to persist any more information, unless the client will be persisting all other state across client restart, in which case, the server will never see any NFSv4.1-level protocol manifestation of a client restart. If the replier is a server, with just the slot table and session ID persisting, any requests the client retries after the server restart will return the results that are cached in the reply cache, and any new requests (i.e., the sequence ID is one greater than the slot's sequence ID) MUST be rejected with NFS4ERR_DEADSESSION (returned by SEQUENCE). Such a session is considered dead. A server MAY re-animate a session after a server restart so that the session will accept new requests as well as retries. To re-animate a session, the server needs to persist additional information through server restart:


* The client ID. This is a prerequisite to let the client create more sessions associated with the same client ID as the re-animated session.

* クライアントID。これは、クライアントに再アニメーションセッションと同じクライアントIDに関連付けられているより多くのセッションを作成させるための前提条件です。

* The client ID's sequence ID that is used for creating sessions (see Sections 18.35 and 18.36). This is a prerequisite to let the client create more sessions.

* セッションの作成に使用されるクライアントIDのシーケンスID(セクション18.35および18.36を参照)。これは、クライアントにより多くのセッションを作成させるための前提条件です。

* The principal that created the client ID. This allows the server to authenticate the client when it sends EXCHANGE_ID.

* クライアントIDを作成した主体。これにより、Exchange_IDを送信するとサーバーはクライアントを認証できます。

* The SSV, if SP4_SSV state protection was specified when the client ID was created (see Section 18.35). This lets the client create new sessions, and associate connections with the new and existing sessions.

* SP4_SSV状態保護がクライアントIDが作成されたときに指定されている場合は、SSV(セクション18.35を参照)。これにより、クライアントは新しいセッションを作成し、新しいセッションと既存のセッションとの接続を関連付けます。

* The properties of the client ID as defined in Section 18.35.

* セクション18.35で定義されているクライアントIDのプロパティ。

A persistent reply cache places certain demands on the server. The execution of the sequence of operations (starting with SEQUENCE) and placement of its results in the persistent cache MUST be atomic. If a client retries a sequence of operations that was previously executed on the server, the only acceptable outcomes are either the original cached reply or an indication that the client ID or session has been lost (indicating a catastrophic loss of the reply cache or a session that has been deleted because the client failed to use the session for an extended period of time).


A server could fail and restart in the middle of a COMPOUND procedure that contains one or more non-idempotent or idempotent-but-modifying operations. This creates an even higher challenge for atomic execution and placement of results in the reply cache. One way to view the problem is as a single transaction consisting of each operation in the COMPOUND followed by storing the result in persistent storage, then finally a transaction commit. If there is a failure before the transaction is committed, then the server rolls back the transaction. If the server itself fails, then when it restarts, its recovery logic could roll back the transaction before starting the NFSv4.1 server.


While the description of the implementation for atomic execution of the request and caching of the reply is beyond the scope of this document, an example implementation for NFSv2 [45] is described in [46].

要求の原子的実行のための実装と応答のキャッシングの実装の説明はこの文書の範囲を超えていますが、NFSV2 [45]の実装例を[46]に説明します。

2.10.7. RDMA Considerations
2.10.7. RDMAの考慮事項

A complete discussion of the operation of RPC-based protocols over RDMA transports is in [32]. A discussion of the operation of NFSv4, including NFSv4.1, over RDMA is in [33]. Where RDMA is considered, this specification assumes the use of such a layering; it addresses only the upper-layer issues relevant to making best use of RPC/RDMA.

RDMAトランスポートを介したRPCベースのプロトコルの動作についての完全な説明は[32]にあります。NFSV4.1を含むNFSV4の操作についての議論は[33]にあります。RDMAが考慮される場合、この仕様はそのような階層化の使用を想定しています。RPC / RDMAを最大限に活用するには関連する上位層の問題だけです。 RDMA Connection Resources RDMA接続リソース

RDMA requires its consumers to register memory and post buffers of a specific size and number for receive operations.


Registration of memory can be a relatively high-overhead operation, since it requires pinning of buffers, assignment of attributes (e.g., readable/writable), and initialization of hardware translation. Preregistration is desirable to reduce overhead. These registrations are specific to hardware interfaces and even to RDMA connection endpoints; therefore, negotiation of their limits is desirable to manage resources effectively.


Following basic registration, these buffers must be posted by the RPC layer to handle receives. These buffers remain in use by the RPC/ NFSv4.1 implementation; the size and number of them must be known to the remote peer in order to avoid RDMA errors that would cause a fatal error on the RDMA connection.

基本登録後、これらのバッファは受信を処理するためにRPCレイヤによって転記されなければなりません。これらのバッファは、RPC / NFSV4.1実装によって使用されています。RDMA接続で致命的なエラーを引き起こす可能性があるRDMAエラーを回避するために、それらのサイズと数はリモートピアに知られている必要があります。

NFSv4.1 manages slots as resources on a per-session basis (see Section 2.10), while RDMA connections manage credits on a per-connection basis. This means that in order for a peer to send data over RDMA to a remote buffer, it has to have both an NFSv4.1 slot and an RDMA credit. If multiple RDMA connections are associated with a session, then if the total number of credits across all RDMA connections associated with the session is X, and the number of slots in the session is Y, then the maximum number of outstanding requests is the lesser of X and Y.

NFSV4.1は、セッションごとにリソースとしてスロットを管理します(セクション2.10を参照)、RDMA接続は接続ごとにクレジットを管理します。つまり、ピアがRDMAを介してリモートバッファにデータを送信するためには、NFSV4.1スロットとRDMAクレジットの両方を持つ必要があります。複数のRDMA接続がセッションに関連付けられている場合、セッションに関連付けられているすべてのRDMA接続にわたるクレジットの総数がXの場合、セッション内のスロット数がYの場合は、最低限の要求の数が少なくなります。xとy。 Flow Control フロー制御

Previous versions of NFS do not provide flow control; instead, they rely on the windowing provided by transports like TCP to throttle requests. This does not work with RDMA, which provides no operation flow control and will terminate a connection in error when limits are exceeded. Limits such as maximum number of requests outstanding are therefore negotiated when a session is created (see the ca_maxrequests field in Section 18.36). These limits then provide the maxima within which each connection associated with the session's channel(s) must remain. RDMA connections are managed within these limits as described in Section 3.3 of [32]; if there are multiple RDMA connections, then the maximum number of requests for a channel will be divided among the RDMA connections. Put a different way, the onus is on the replier to ensure that the total number of RDMA credits across all connections associated with the replier's channel does exceed the channel's maximum number of outstanding requests.


The limits may also be modified dynamically at the replier's choosing by manipulating certain parameters present in each NFSv4.1 reply. In addition, the CB_RECALL_SLOT callback operation (see Section 20.8) can be sent by a server to a client to return RDMA credits to the server, thereby lowering the maximum number of requests a client can have outstanding to the server.

各NFSV4.1応答に存在する特定のパラメータを操作することによって、リプライアの選択では、限界を動的に変更することもできます。さらに、CB_RECALL_SLOTコールバック操作(セクション20.8を参照)をサーバーに送信して、RDMAクレジットをサーバーに戻すためにクライアントに送信でき、それによってクライアントがサーバーに優れている要求の最大要求数を下げることができます。 Padding パディング

Header padding is requested by each peer at session initiation (see the ca_headerpadsize argument to CREATE_SESSION in Section 18.36), and subsequently used by the RPC RDMA layer, as described in [32]. Zero padding is permitted.

ヘッダーパディングは、セッション開始時に各ピアによって要求されます(セクション18.36のCATE_SESSERT_SESSIONの引数を参照)、[32]の説明に従って、RPC RDMAレイヤによって使用されます。ゼロパディングが許可されています。

Padding leverages the useful property that RDMA preserve alignment of data, even when they are placed into anonymous (untagged) buffers. If requested, client inline writes will insert appropriate pad bytes within the request header to align the data payload on the specified boundary. The client is encouraged to add sufficient padding (up to the negotiated size) so that the "data" field of the WRITE operation is aligned. Most servers can make good use of such padding, which allows them to chain receive buffers in such a way that any data carried by client requests will be placed into appropriate buffers at the server, ready for file system processing. The receiver's RPC layer encounters no overhead from skipping over pad bytes, and the RDMA layer's high performance makes the insertion and transmission of padding on the sender a significant optimization. In this way, the need for servers to perform RDMA Read to satisfy all but the largest client writes is obviated. An added benefit is the reduction of message round trips on the network -- a potentially good trade, where latency is present.

パディングは、RDMAがデータのアライメントを保存する有用なプロパティを活用します。要求された場合、クライアントのインライン書き込みは要求ヘッダー内に適切なパッドバイトを挿入して、指定された境界上のデータペイロードを揃えます。クライアントは、書き込み操作の「データ」フィールドが整列されるように十分なパディング(ネゴシエートされたサイズまで)を追加することが奨励されます。ほとんどのサーバーはそのようなパディングをよく使用できます。受信機のRPCレイヤーはパッドバイトをスキップすることからオーバーヘッドを遭遇しないため、RDMAレイヤーの高性能は、送信者にとってパディングの挿入と伝送を大切に最適化します。このようにして、サーバが最大のクライアント書き込みを満たすためにRDMAを読み取る必要性が排除される。追加された利点は、ネットワーク上のメッセージ往復の削減です - 待ち時間が存在する潜在的に良い貿易。

The value to choose for padding is subject to a number of criteria. A primary source of variable-length data in the RPC header is the authentication information, the form of which is client-determined, possibly in response to server specification. The contents of COMPOUNDs, sizes of strings such as those passed to RENAME, etc. all go into the determination of a maximal NFSv4.1 request size and therefore minimal buffer size. The client must select its offered value carefully, so as to avoid overburdening the server, and vice versa. The benefit of an appropriate padding value is higher performance.


                    Sender gather:
        |RPC Request|Pad  bytes|Length| -> |User data...|
        \------+----------------------/      \
                \                             \
                 \    Receiver scatter:        \-----------+- ...
            /-----+----------------\            \           \
            |RPC Request|Pad|Length|   ->  |FS buffer|->|FS buffer|->...

In the above case, the server may recycle unused buffers to the next posted receive if unused by the actual received request, or may pass the now-complete buffers by reference for normal write processing. For a server that can make use of it, this removes any need for data copies of incoming data, without resorting to complicated end-to-end buffer advertisement and management. This includes most kernel-based and integrated server designs, among many others. The client may perform similar optimizations, if desired.

上記の場合、サーバは、実際の受信要求によって未使用で未使用のバッファを次の投稿受信にリサイクルすることも、通常の書き込み処理のために参照により現在完全なバッファを渡すことができる。それを利用できるサーバーの場合、複雑なエンドツーエンドバッファー広告と管理に頼ることなく、着信データのデータコピーの必要性を削除します。これには、ほとんどのカーネルベースの設計と統合されたサーバーの設計が含まれています。必要に応じて、クライアントは同様の最適化を実行することができる。 Dual RDMA and Non-RDMA Transports デュアルRDMAと非RDMAトランスポート

Some RDMA transports (e.g., RFC 5040 [8]) permit a "streaming" (non-RDMA) phase, where ordinary traffic might flow before "stepping up" to RDMA mode, commencing RDMA traffic. Some RDMA transports start connections always in RDMA mode. NFSv4.1 allows, but does not assume, a streaming phase before RDMA mode. When a connection is associated with a session, the client and server negotiate whether the connection is used in RDMA or non-RDMA mode (see Sections 18.36 and 18.34).

いくつかのRDMAトランスポート(例えば、RFC 5040 [8])は、RDMAトラフィックを開始する「ストリーミング」(RDMA)フェーズを「ストリーミング」(非RDMA)フェーズを許可します。一部のRDMAは常にRDMAモードで接続を開始します。NFSV4.1はRDMAモードの前のストリーミングフェーズを使用することを許可します。接続がセッションに関連付けられている場合、クライアントとサーバーは、接続がRDMAまたは非RDMAモードで使用されているかどうかをネゴシエートします(セクション18.36と18.34を参照)。

2.10.8. Session Security
2.10.8. セッションセキュリティ Session Callback Security セッションコールバックセキュリティ

Via session/connection association, NFSv4.1 improves security over that provided by NFSv4.0 for the backchannel. The connection is client-initiated (see Section 18.34) and subject to the same firewall and routing checks as the fore channel. At the client's option (see Section 18.35), connection association is fully authenticated before being activated (see Section 18.34). Traffic from the server over the backchannel is authenticated exactly as the client specifies (see Section

Session / Connection Associationを介して、NFSV4.1はBackChannelに対してNFSv4.0が提供するセキュリティを向上させます。接続はクライアントが開始され(セクション18.34を参照)、前のチャネルとして同じファイアウォールとルーティングチェックを受けます。クライアントのオプション(セクション18.35を参照)で、接続アソシエーションはアクティブになる前に完全に認証されています(18.34節を参照)。BackChannelを介したサーバーからのトラフィックは、クライアントが指定されているとおりに認証されます(セクション2.10.8.2を参照)。 Backchannel RPC Security BackChannel RPCセキュリティ

When the NFSv4.1 client establishes the backchannel, it informs the server of the security flavors and principals to use when sending requests. If the security flavor is RPCSEC_GSS, the client expresses the principal in the form of an established RPCSEC_GSS context. The server is free to use any of the flavor/principal combinations the client offers, but it MUST NOT use unoffered combinations. This way, the client need not provide a target GSS principal for the backchannel as it did with NFSv4.0, nor does the server have to implement an RPCSEC_GSS initiator as it did with NFSv4.0 [37].

NFSV4.1クライアントがBackChannelを確立すると、リクエストの送信時に使用するセキュリティフレーバーとプリンシパルのサーバーに通知します。セキュリティフレーバーがRPCSEC_GSSの場合、クライアントは確立されたRPCSEC_GSSコンテキストの形式でプリンシパルを表します。サーバーはクライアントのオファーのいずれかのフレーバー/プリンシパルの組み合わせを自由に使用できますが、未払いの組み合わせを使用しないでください。このようにして、クライアントはNFSv4.0と同じようにBackChannelのターゲットGSSプリンシパルを提供する必要もなく、NFSv4.0 [37]と同じようにサーバはRPCSEC_GSSイニシエータを実装する必要もありません[37]。

The CREATE_SESSION (Section 18.36) and BACKCHANNEL_CTL (Section 18.33) operations allow the client to specify flavor/ principal combinations.


Also note that the SP4_SSV state protection mode (see Sections 18.35 and has the side benefit of providing SSV-derived RPCSEC_GSS contexts (Section 2.10.9).

また、SP4_SSV状態保護モード(セクション18.35および2.10.8.3を参照)は、SSV派生RPCSEC_GSSコンテキストを提供することのサイドの利点を有する(2.10.9項)。 Protection from Unauthorized State Changes 不正状態の変更からの保護

As described to this point in the specification, the state model of NFSv4.1 is vulnerable to an attacker that sends a SEQUENCE operation with a forged session ID and with a slot ID that it expects the legitimate client to use next. When the legitimate client uses the slot ID with the same sequence number, the server returns the attacker's result from the reply cache, which disrupts the legitimate client and thus denies service to it. Similarly, an attacker could send a CREATE_SESSION with a forged client ID to create a new session associated with the client ID. The attacker could send requests using the new session that change locking state, such as LOCKU operations to release locks the legitimate client has acquired. Setting a security policy on the file that requires RPCSEC_GSS credentials when manipulating the file's state is one potential work around, but has the disadvantage of preventing a legitimate client from releasing state when RPCSEC_GSS is required to do so, but a GSS context cannot be obtained (possibly because the user has logged off the client).

本明細書のこの点について説明したように、NFSV4.1の状態モデルは、鍛造セッションIDと、Regitimeimeクライアントが次に使用することを期待するスロットIDを持つシーケンス操作を送信する攻撃者に対して脆弱です。合法的なクライアントが同じシーケンス番号を持つスロットIDを使用すると、サーバーは応答キャッシュからの攻撃者の結果を返します。これにより正当なクライアントが混乱し、したがってサービスを拒否します。同様に、攻撃者は、クライアントIDに関連付けられている新しいセッションを作成するために、攻撃者が偽造クライアントIDを登録することができます。攻撃者は、Resku Operations Locks Locks Locks Resking Locksを取得した場合の新しいセッションを使用してリクエストを送信できます。ファイルの状態を操作するときにRPCSEC_GSS認証情報を必要とするファイルのセキュリティポリシーを設定することは、RPCSEC_GSSが必要なときに正当なクライアントの解放を防ぐという欠点がありますが、GSSコンテキストは取得できません(ユーザーがクライアントからログオフしたからです。

NFSv4.1 provides three options to a client for state protection, which are specified when a client creates a client ID via EXCHANGE_ID (Section 18.35).


The first (SP4_NONE) is to simply waive state protection.


The other two options (SP4_MACH_CRED and SP4_SSV) share several traits:


* An RPCSEC_GSS-based credential is used to authenticate client ID and session maintenance operations, including creating and destroying a session, associating a connection with the session, and destroying the client ID.

* rpcsec_gssベースの信任状は、セッションの作成と破棄、セッションとの接続を関連付け、クライアントIDを破棄するなど、クライアントIDとセッションのメンテナンス操作を認証するために使用されます。

* Because RPCSEC_GSS is used to authenticate client ID and session maintenance, the attacker cannot associate a rogue connection with a legitimate session, or associate a rogue session with a legitimate client ID in order to maliciously alter the client ID's lock state via CLOSE, LOCKU, DELEGRETURN, LAYOUTRETURN, etc.

* RPCSEC_GSSはクライアントIDとセッションのメンテナンスを認証するために使用されているため、攻撃者は正当なセッションとの不正なセッションを関連付けることも、クライアントIDのロック状態を閉鎖、Locku、DelegReturnで故意に変更するために正当なクライアントIDとの不正なセッションを関連付けることもできません。、LayoutReturnなど

* In cases where the server's security policies on a portion of its namespace require RPCSEC_GSS authentication, a client may have to use an RPCSEC_GSS credential to remove per-file state (e.g., LOCKU, CLOSE, etc.). The server may require that the principal that removes the state match certain criteria (e.g., the principal might have to be the same as the one that acquired the state). However, the client might not have an RPCSEC_GSS context for such a principal, and might not be able to create such a context (perhaps because the user has logged off). When the client establishes SP4_MACH_CRED or SP4_SSV protection, it can specify a list of operations that the server MUST allow using the machine credential (if SP4_MACH_CRED is used) or the SSV credential (if SP4_SSV is used).

* ネームスペースの一部でサーバーのセキュリティポリシーがRPCSEC_GSS認証を必要とする場合、クライアントはファイルごとの状態(例えば、ロック、クローズなど)を削除するためにRPCSEC_GSSクレデンシャルを使用する必要があります。サーバは、状態を削除する主体が特定の基準と一致する(例えば、主体を取得したものと同じでなければならないかもしれない)。ただし、クライアントはそのようなプリンシパルのためのRPCSEC_GSSコンテキストを持っていない可能性があり、そのようなコンテキストを作成できない可能性があります(ユーザーがログオフしたためにおそらく)。クライアントがSP4_MACH_CREDまたはSP4_SSV保護を確立すると、サーバーがマシンの信任状(SP4_MACH_CREDが使用されている場合)またはSSV認証情報(SP4_SSVが使用されている場合)を使用する必要がある操作のリストを指定できます。

The SP4_MACH_CRED state protection option uses a machine credential where the principal that creates the client ID MUST also be the principal that performs client ID and session maintenance operations. The security of the machine credential state protection approach depends entirely on safeguarding the per-machine credential. Assuming a proper safeguard using the per-machine credential for operations like CREATE_SESSION, BIND_CONN_TO_SESSION, DESTROY_SESSION, and DESTROY_CLIENTID will prevent an attacker from associating a rogue connection with a session, or associating a rogue session with a client ID.


There are at least three scenarios for the SP4_MACH_CRED option:


1. The system administrator configures a unique, permanent per-machine credential for one of the mandated GSS mechanisms (e.g., if Kerberos V5 is used, a "keytab" containing a principal derived from a client host name could be used).

1. システム管理者は、必須のGSSメカニズムの1つに対して一意の永続的なマシンの信任状を設定します(例えば、Kerberos V5が使用されている場合は、クライアントホスト名から派生したプリンシパルを含む「KeyTab」を使用できる)。

2. The client is used by a single user, and so the client ID and its sessions are used by just that user. If the user's credential expires, then session and client ID maintenance cannot occur, but since the client has a single user, only that user is inconvenienced.

2. クライアントは単一のユーザーによって使用されているので、クライアントIDとそのセッションはそのユーザーだけで使用されます。ユーザーの資格情報が期限切れになると、セッションとクライアントIDのメンテナンスが発生することはできませんが、クライアントには単一のユーザーがあるため、そのユーザーのみが不便です。

3. The physical client has multiple users, but the client implementation has a unique client ID for each user. This is effectively the same as the second scenario, but a disadvantage is that each user needs to be allocated at least one session each, so the approach suffers from lack of economy.

3. 物理クライアントに複数のユーザーがありますが、クライアント実装には各ユーザーに固有のクライアントIDがあります。これは2番目のシナリオと同じですが、それぞれのユーザーをそれぞれ少なくとも1つのセッションを割り当てる必要があることがあります。

The SP4_SSV protection option uses the SSV (Section 1.7), via RPCSEC_GSS and the SSV GSS mechanism (Section 2.10.9), to protect state from attack. The SP4_SSV protection option is intended for the situation comprised of a client that has multiple active users and a system administrator who wants to avoid the burden of installing a permanent machine credential on each client. The SSV is established and updated on the server via SET_SSV (see Section 18.47). To prevent eavesdropping, a client SHOULD send SET_SSV via RPCSEC_GSS with the privacy service. Several aspects of the SSV make it intractable for an attacker to guess the SSV, and thus associate rogue connections with a session, and rogue sessions with a client ID:

SP4_SSV保護オプションは、攻撃から状態を保護するために、RPCSEC_GSSおよびSSV GSSメカニズム(セクション2.10.9)を介してSSV(1.7)を使用します。SP4_SSV保護オプションは、複数のアクティブなユーザーを持つクライアントと、各クライアントに永続的なマシンの資格情報をインストールするという負担を避けたいシステム管理者とからなる状況を目的としています。SSVはset_ssvを介してサーバー上で確立され更新されます(18.47節を参照)。盗聴を防ぐために、クライアントはPrivacy Serviceを使用してRPCSEC_GSSを介してset_ssvを送信する必要があります。SSVのいくつかの側面は、攻撃者がSSVを推測するために扱いやすく、したがって不正な接続をセッションと関連付け、クライアントIDとの不正なセッションを関連付けます。

* The arguments to and results of SET_SSV include digests of the old and new SSV, respectively.

* set_ssvの引数と結果には、それぞれ古いSSVと新しいSSVのダイジェストが含まれます。

* Because the initial value of the SSV is zero, therefore known, the client that opts for SP4_SSV protection and opts to apply SP4_SSV protection to BIND_CONN_TO_SESSION and CREATE_SESSION MUST send at least one SET_SSV operation before the first BIND_CONN_TO_SESSION operation or before the second CREATE_SESSION operation on a client ID. If it does not, the SSV mechanism will not generate tokens (Section 2.10.9). A client SHOULD send SET_SSV as soon as a session is created.

* したがって、SSVの初期値はゼロであるため、既知であるため、SP4_SSV保護をオプションし、SP4_SSV保護をBIND_CONN_TO_SESSIONに適用し、CREATE_SESSESTをOPTにする必要があります。クライアントID。そうでない場合、SSVメカニズムはトークンを生成しません(セクション2.10.9)。セッションが作成されるとすぐにクライアントがset_ssvを送信する必要があります。

* A SET_SSV request does not replace the SSV with the argument to SET_SSV. Instead, the current SSV on the server is logically exclusive ORed (XORed) with the argument to SET_SSV. Each time a new principal uses a client ID for the first time, the client SHOULD send a SET_SSV with that principal's RPCSEC_GSS credentials, with RPCSEC_GSS service set to RPC_GSS_SVC_PRIVACY.

* set_ssv要求は、SSVを引数に置き換えない。代わりに、サーバー上の現在のSSVは論理的に排他的または引数を指定してset_ssvへの引数です。新しいプリンシパルが初めてクライアントIDを使用するたびに、クライアントはそのプリンシパルのRPCSEC_GSSクレデンシャルを使用してset_ssvを送信し、RPCSEC_GSSサービスはRPC_GSS_SVC_PRIVACYに設定されています。

Here are the types of attacks that can be attempted by an attacker named Eve on a victim named Bob, and how SP4_SSV protection foils each attack:


* Suppose Eve is the first user to log into a legitimate client. Eve's use of an NFSv4.1 file system will cause the legitimate client to create a client ID with SP4_SSV protection, specifying that the BIND_CONN_TO_SESSION operation MUST use the SSV credential. Eve's use of the file system also causes an SSV to be created. The SET_SSV operation that creates the SSV will be protected by the RPCSEC_GSS context created by the legitimate client, which uses Eve's GSS principal and credentials. Eve can eavesdrop on the network while her RPCSEC_GSS context is created and the SET_SSV using her context is sent. Even if the legitimate client sends the SET_SSV with RPC_GSS_SVC_PRIVACY, because Eve knows her own credentials, she can decrypt the SSV. Eve can compute an RPCSEC_GSS credential that BIND_CONN_TO_SESSION will accept, and so associate a new connection with the legitimate session. Eve can change the slot ID and sequence state of a legitimate session, and/or the SSV state, in such a way that when Bob accesses the server via the same legitimate client, the legitimate client will be unable to use the session.

* EVEが正当なクライアントにログインする最初のユーザーであるとします。 EveのNFSV4.1ファイルシステムの使用により、RegitimeクライアントがSP4_SSV保護を使用してクライアントIDを作成し、BIND_CONN_TO_SESSION操作がSSV認証情報を使用する必要があることを指定します。ファイルシステムのEVEの使用により、SSVが作成されます。 SSVを作成するSET_SSV操作は、Regitimate Clientによって作成されたRPCSEC_GSSコンテキストによって保護され、これはEveのGSSプリンシパルと資格情報を使用します。彼女のrpcsec_gssコンテキストが作成され、彼女のコンテキストを使用してset_ssvが送信されている間、Eveはネットワーク上で盗聴することができます。正当なクライアントがRPC_GSS_SVC_PRIVACYを使用してSET_SSVを送信しても、EVEは自分の資格情報を知っているため、SSVを復号化できます。 EVEは、bind_conn_to_sessionが受け入れるRPCSEC_GSSクレデンシャルを計算でき、新しい接続を正当なセッションに関連付けます。 EVEは、BOBが同じRegitimateクライアントを介してサーバーにアクセスすると、正当なクライアントがセッションを使用できなくなるように、EVEは正当なセッションとSEQUENT状態のスロットIDとシーケンス状態を変更できます。

The client's only recourse is to create a new client ID for Bob to use, and establish a new SSV for the client ID. The client will be unable to delete the old client ID, and will let the lease on the old client ID expire.


Once the legitimate client establishes an SSV over the new session using Bob's RPCSEC_GSS context, Eve can use the new session via the legitimate client, but she cannot disrupt Bob. Moreover, because the client SHOULD have modified the SSV due to Eve using the new session, Bob cannot get revenge on Eve by associating a rogue connection with the session.


The question is how did the legitimate client detect that Eve has hijacked the old session? When the client detects that a new principal, Bob, wants to use the session, it SHOULD have sent a SET_SSV, which leads to the following sub-scenarios:


- Let us suppose that from the rogue connection, Eve sent a SET_SSV with the same slot ID and sequence ID that the legitimate client later uses. The server will assume the SET_SSV sent with Bob's credentials is a retry, and return to the legitimate client the reply it sent Eve. However, unless Eve can correctly guess the SSV the legitimate client will use, the digest verification checks in the SET_SSV response will fail. That is an indication to the client that the session has apparently been hijacked.

- Rogue接続からEVEがSET_SSVをSET_SSVに送信させて、正当なクライアントが後で使用するのと同じスロットIDとシーケンスIDを送信しました。サーバーは、BOBの認証情報が再試行で送信されたSET_SSSVが想定され、Reptimate Clientに戻ってEveを送信します。ただし、EVEが正当なクライアントが使用するSSVを正しく推測できる限り、SET_SSV応答のダイジェスト検証チェックは失敗します。これは、セッションが明らかにハイジャックされたことをクライアントに指示しています。

- Alternatively, Eve sent a SET_SSV with a different slot ID than the legitimate client uses for its SET_SSV. Then the digest verification of the SET_SSV sent with Bob's credentials fails on the server, and the error returned to the client makes it apparent that the session has been hijacked.

- あるいは、EVEはそのset_ssvのために正当なクライアントが使用するのとは異なるスロットIDを持つset_ssvを送信しました。その後、BOBの資格情報を送信したSET_SSVのダイジェスト検証はサーバー上で失敗し、クライアントに返されたエラーは、セッションがハイジャックされたことを明らかにします。

- Alternatively, Eve sent an operation other than SET_SSV, but with the same slot ID and sequence that the legitimate client uses for its SET_SSV. The server returns to the legitimate client the response it sent Eve. The client sees that the response is not at all what it expects. The client assumes either session hijacking or a server bug, and either way destroys the old session.

- あるいは、EVEはset_ssv以外の操作を送信しましたが、正当なクライアントがそのset_ssvに使用するのと同じスロットIDとシーケンスを使用します。サーバーは、Eveを送信した応答を正当なクライアントに戻ります。クライアントは、対応がそれが期待するものだけではないことを見ています。クライアントはセッションハイジャックまたはサーバーのバグのいずれかを想定しており、どちらの方法で古いセッションを破棄します。

* Eve associates a rogue connection with the session as above, and then destroys the session. Again, Bob goes to use the server from the legitimate client, which sends a SET_SSV using Bob's credentials. The client receives an error that indicates that the session does not exist. When the client tries to create a new session, this will fail because the SSV it has does not match that which the server has, and now the client knows the session was hijacked. The legitimate client establishes a new client ID.

* EVEは上記のように不正な接続をセッションに関連付けてからセッションを破棄します。繰り返しますが、Bobは正当なクライアントからサーバーを使用します。これは、BOBの資格情報を使用してset_ssvを送信します。クライアントは、セッションが存在しないことを示すエラーを受け取ります。クライアントが新しいセッションを作成しようとすると、SSVがサーバーが持っているものと一致しないため、これは失敗し、クライアントはセッションをハイジャックされたことを認識しました。合法的なクライアントは新しいクライアントIDを確立します。

* If Eve creates a connection before the legitimate client establishes an SSV, because the initial value of the SSV is zero and therefore known, Eve can send a SET_SSV that will pass the digest verification check. However, because the new connection has not been associated with the session, the SET_SSV is rejected for that reason.

* RegitimateクライアントがSSVを確立する前にEVEが接続を作成する場合、SSVの初期値はゼロ、したがって既知であるため、EVEはダイジェスト検証チェックを渡すSET_SSVを送信できます。ただし、新しい接続がセッションに関連付けられていないため、set_ssvはその理由で拒否されます。

In summary, an attacker's disruption of state when SP4_SSV protection is in use is limited to the formative period of a client ID, its first session, and the establishment of the SSV. Once a non-malicious user uses the client ID, the client quickly detects any hijack and rectifies the situation. Once a non-malicious user successfully modifies the SSV, the attacker cannot use NFSv4.1 operations to disrupt the non-malicious user.


Note that neither the SP4_MACH_CRED nor SP4_SSV protection approaches prevent hijacking of a transport connection that has previously been associated with a session. If the goal of a counter-threat strategy is to prevent connection hijacking, the use of IPsec is RECOMMENDED.


If a connection hijack occurs, the hijacker could in theory change locking state and negatively impact the service to legitimate clients. However, if the server is configured to require the use of RPCSEC_GSS with integrity or privacy on the affected file objects, and if EXCHGID4_FLAG_BIND_PRINC_STATEID capability (Section 18.35) is in force, this will thwart unauthorized attempts to change locking state.


2.10.9. The Secret State Verifier (SSV) GSS Mechanism
2.10.9. 秘密状態検証者(SSV)GSS機構

The SSV provides the secret key for a GSS mechanism internal to NFSv4.1 that NFSv4.1 uses for state protection. Contexts for this mechanism are not established via the RPCSEC_GSS protocol. Instead, the contexts are automatically created when EXCHANGE_ID specifies SP4_SSV protection. The only tokens defined are the PerMsgToken (emitted by GSS_GetMIC) and the SealedMessage token (emitted by GSS_Wrap).


The mechanism OID for the SSV mechanism is Eisler.nfs.ssv_mech ( While the SSV mechanism does not define any initial context tokens, the OID can be used to let servers indicate that the SSV mechanism is acceptable whenever the client sends a SECINFO or SECINFO_NO_NAME operation (see Section 2.6).

SSVメカニズムのためのメカニズムOIDは Eisler.nfs.sv_mech(です。SSVメカニズムは初期コンテキストトークンを定義していない間、OIDを使用して、サーバーを使用して、クライアントがSECINFOまたはSECINFO_NO_NAME操作を送信するたびにSSVメカニズムが許容できることを示します(セクション2.6を参照)。

The SSV mechanism defines four subkeys derived from the SSV value. Each time SET_SSV is invoked, the subkeys are recalculated by the client and server. The calculation of each of the four subkeys depends on each of the four respective ssv_subkey4 enumerated values. The calculation uses the HMAC [52] algorithm, using the current SSV as the key, the one-way hash algorithm as negotiated by EXCHANGE_ID, and the input text as represented by the XDR encoded enumeration value for that subkey of data type ssv_subkey4. If the length of the output of the HMAC algorithm exceeds the length of key of the encryption algorithm (which is also negotiated by EXCHANGE_ID), then the subkey MUST be truncated from the HMAC output, i.e., if the subkey is of N bytes long, then the first N bytes of the HMAC output MUST be used for the subkey. The specification of EXCHANGE_ID states that the length of the output of the HMAC algorithm MUST NOT be less than the length of subkey needed for the encryption algorithm (see Section 18.35).

SSVメカニズムは、SSV値から派生した4つのサブキーを定義します。 set_ssvが呼び出されるたびに、サブキーはクライアントとサーバーによって再計算されます。 4つのサブキーのそれぞれの計算は、それぞれのそれぞれのSSV_SUBKEY4列挙値のそれぞれによって異なります。この計算は、現在のSSVをキーとしてのHMAC [52]アルゴリズム、Exchange_IDによってネゴシエートされた一方向ハッシュアルゴリズム、およびデータ型SSV_SUBKEY4のそのサブキーのXDRエンコードされた列挙値によって表される入力テキストを使用します。 HMACアルゴリズムの出力の長さが暗号化アルゴリズムのキーの長さを超えている場合(これはExchange_IDによってもネゴシエートされます)、サブキーはHMAC出力から切り捨てられなければならず、すなわちサブキーがnバイトの長さである場合、その後、HMAC出力の最初のNバイトをサブキーに使用する必要があります。 Exchange_idの指定は、HMACアルゴリズムの出力の長さが暗号化アルゴリズムに必要なサブキーの長さよりも小さくなければならないことを示しています(セクション18.35を参照)。

   /* Input for computing subkeys */
   enum ssv_subkey4 {
           SSV4_SUBKEY_MIC_I2T     = 1,
           SSV4_SUBKEY_MIC_T2I     = 2,
           SSV4_SUBKEY_SEAL_I2T    = 3,
           SSV4_SUBKEY_SEAL_T2I    = 4

The subkey derived from SSV4_SUBKEY_MIC_I2T is used for calculating message integrity codes (MICs) that originate from the NFSv4.1 client, whether as part of a request over the fore channel or a response over the backchannel. The subkey derived from SSV4_SUBKEY_MIC_T2I is used for MICs originating from the NFSv4.1 server. The subkey derived from SSV4_SUBKEY_SEAL_I2T is used for encryption text originating from the NFSv4.1 client, and the subkey derived from SSV4_SUBKEY_SEAL_T2I is used for encryption text originating from the NFSv4.1 server.


The PerMsgToken description is based on an XDR definition:


   /* Input for computing smt_hmac */
   struct ssv_mic_plain_tkn4 {
     uint32_t        smpt_ssv_seq;
     opaque          smpt_orig_plain<>;
   /* SSV GSS PerMsgToken token */
   struct ssv_mic_tkn4 {
     uint32_t        smt_ssv_seq;
     opaque          smt_hmac<>;

The field smt_hmac is an HMAC calculated by using the subkey derived from SSV4_SUBKEY_MIC_I2T or SSV4_SUBKEY_MIC_T2I as the key, the one-way hash algorithm as negotiated by EXCHANGE_ID, and the input text as represented by data of type ssv_mic_plain_tkn4. The field smpt_ssv_seq is the same as smt_ssv_seq. The field smpt_orig_plain is the "message" input passed to GSS_GetMIC() (see Section 2.3.1 of [7]). The caller of GSS_GetMIC() provides a pointer to a buffer containing the plain text. The SSV mechanism's entry point for GSS_GetMIC() encodes this into an opaque array, and the encoding will include an initial four-byte length, plus any necessary padding. Prepended to this will be the XDR encoded value of smpt_ssv_seq, thus making up an XDR encoding of a value of data type ssv_mic_plain_tkn4, which in turn is the input into the HMAC.


The token emitted by GSS_GetMIC() is XDR encoded and of XDR data type ssv_mic_tkn4. The field smt_ssv_seq comes from the SSV sequence number, which is equal to one after SET_SSV (Section 18.47) is called the first time on a client ID. Thereafter, the SSV sequence number is incremented on each SET_SSV. Thus, smt_ssv_seq represents the version of the SSV at the time GSS_GetMIC() was called. As noted in Section 18.35, the client and server can maintain multiple concurrent versions of the SSV. This allows the SSV to be changed without serializing all RPC calls that use the SSV mechanism with SET_SSV operations. Once the HMAC is calculated, it is XDR encoded into smt_hmac, which will include an initial four-byte length, and any necessary padding. Prepended to this will be the XDR encoded value of smt_ssv_seq.


The SealedMessage description is based on an XDR definition:


   /* Input for computing ssct_encr_data and ssct_hmac */
   struct ssv_seal_plain_tkn4 {
     opaque          sspt_confounder<>;
     uint32_t        sspt_ssv_seq;
     opaque          sspt_orig_plain<>;
     opaque          sspt_pad<>;
   /* SSV GSS SealedMessage token */
   struct ssv_seal_cipher_tkn4 {
     uint32_t      ssct_ssv_seq;
     opaque        ssct_iv<>;
     opaque        ssct_encr_data<>;
     opaque        ssct_hmac<>;

The token emitted by GSS_Wrap() is XDR encoded and of XDR data type ssv_seal_cipher_tkn4.


The ssct_ssv_seq field has the same meaning as smt_ssv_seq.


The ssct_encr_data field is the result of encrypting a value of the XDR encoded data type ssv_seal_plain_tkn4. The encryption key is the subkey derived from SSV4_SUBKEY_SEAL_I2T or SSV4_SUBKEY_SEAL_T2I, and the encryption algorithm is that negotiated by EXCHANGE_ID.


The ssct_iv field is the initialization vector (IV) for the encryption algorithm (if applicable) and is sent in clear text. The content and size of the IV MUST comply with the specification of the encryption algorithm. For example, the id-aes256-CBC algorithm MUST use a 16-byte initialization vector (IV), which MUST be unpredictable for each instance of a value of data type ssv_seal_plain_tkn4 that is encrypted with a particular SSV key.


The ssct_hmac field is the result of computing an HMAC using the value of the XDR encoded data type ssv_seal_plain_tkn4 as the input text. The key is the subkey derived from SSV4_SUBKEY_MIC_I2T or SSV4_SUBKEY_MIC_T2I, and the one-way hash algorithm is that negotiated by EXCHANGE_ID.


The sspt_confounder field is a random value.


The sspt_ssv_seq field is the same as ssvt_ssv_seq.


The field sspt_orig_plain field is the original plaintext and is the "input_message" input passed to GSS_Wrap() (see Section 2.3.3 of [7]). As with the handling of the plaintext by the SSV mechanism's GSS_GetMIC() entry point, the entry point for GSS_Wrap() expects a pointer to the plaintext, and will XDR encode an opaque array into sspt_orig_plain representing the plain text, along with the other fields of an instance of data type ssv_seal_plain_tkn4.

フィールドSSPT_ORIG_PLAINフィールドは元の平文で、GSS_WRAP()に渡された "input_message"入力です([7]のセクション2.3.3を参照)。SSVメカニズムのGSS_GETMIC()エントリポイントによる平文の処理と同様に、GSS_WRAP()のエントリポイントは平文へのポインタを想定し、XDRはプレーンテキストを表すSSPT_ORIG_PLAINにXDRをエンコードします。データ型SSV_SEAL_PLAIN_TKN4の例。

The sspt_pad field is present to support encryption algorithms that require inputs to be in fixed-sized blocks. The content of sspt_pad is zero filled except for the length. Beware that the XDR encoding of ssv_seal_plain_tkn4 contains three variable-length arrays, and so each array consumes four bytes for an array length, and each array that follows the length is always padded to a multiple of four bytes per the XDR standard.


For example, suppose the encryption algorithm uses 16-byte blocks, and the sspt_confounder is three bytes long, and the sspt_orig_plain field is 15 bytes long. The XDR encoding of sspt_confounder uses eight bytes (4 + 3 + 1-byte pad), the XDR encoding of sspt_ssv_seq uses four bytes, the XDR encoding of sspt_orig_plain uses 20 bytes (4 + 15 + 1-byte pad), and the smallest XDR encoding of the sspt_pad field is four bytes. This totals 36 bytes. The next multiple of 16 is 48; thus, the length field of sspt_pad needs to be set to 12 bytes, or a total encoding of 16 bytes. The total number of XDR encoded bytes is thus 8 + 4 + 20 + 16 = 48.

たとえば、暗号化アルゴリズムが16バイトのブロックを使用し、SSPT_CONOFOUNDERは3バイトの長さで、SSPT_ORIG_PLAINフィールドは15バイト長です。SSPT_CONFOUNDORのXDRエンコーディングは8バイト(4 3 1バイトPAD)を使用しているため、SSPT_SSV_SEQのXDRエンコーディングは4バイトを使用しています.SSPT_ORIG_PLAINのXDRエンコーディングは、20バイト(4 15 1バイトPAD)を使用し、最小のXDRエンコーディングを使用します。SSPT_PADフィールドは4バイトです。この合計36バイト16の次の倍数は48です。したがって、SSPT_PADの長さフィールドは12バイト、または16バイトの総エンコードを設定する必要があります。したがって、XDR符号化バイトの総数は8 4 20 16 = 48である。

GSS_Wrap() emits a token that is an XDR encoding of a value of data type ssv_seal_cipher_tkn4. Note that regardless of whether or not the caller of GSS_Wrap() requests confidentiality, the token always has confidentiality. This is because the SSV mechanism is for RPCSEC_GSS, and RPCSEC_GSS never produces GSS_wrap() tokens without confidentiality.


There is one SSV per client ID. There is a single GSS context for a client ID / SSV pair. All SSV mechanism RPCSEC_GSS handles of a client ID / SSV pair share the same GSS context. SSV GSS contexts do not expire except when the SSV is destroyed (causes would include the client ID being destroyed or a server restart). Since one purpose of context expiration is to replace keys that have been in use for "too long", hence vulnerable to compromise by brute force or accident, the client can replace the SSV key by sending periodic SET_SSV operations, which is done by cycling through different users' RPCSEC_GSS credentials. This way, the SSV is replaced without destroying the SSV's GSS contexts.

クライアントIDごとにSSVが1つあります。クライアントID / SSVペアのための単一のGSSコンテキストがあります。すべてのSSVメカニズムRPCSEC_GSSクライアントID / SSVペアのハンドルは、同じGSSコンテキストを共有します。SSVがSSVが破棄されたときを除いて、SSV GSSコンテキストは期限切れになりません(原因には破棄されているクライアントIDまたはサーバーの再起動が含まれます)。コンテキストの有効期限の目的は、「長すぎる」に使用されているキーを置き換えることです。さまざまなユーザーのRPCSEC_GSS認証情報。このようにして、SSVのGSSコンテキストを破棄することなくSSVが置き換えられます。

SSV RPCSEC_GSS handles can be expired or deleted by the server at any time, and the EXCHANGE_ID operation can be used to create more SSV RPCSEC_GSS handles. Expiration of SSV RPCSEC_GSS handles does not imply that the SSV or its GSS context has expired.

SSV RPCSEC_GSSハンドルはいつでもサーバーによって期限切れまたは削除することができ、Exchange_ID操作を使用してより多くのSSV RPCSEC_GSSハンドルを作成できます。SSV RPCSEC_GSSハンドルの有効期限は、SSVまたはそのGSSコンテキストが期限切れになったことを意味しません。

The client MUST establish an SSV via SET_SSV before the SSV GSS context can be used to emit tokens from GSS_Wrap() and GSS_GetMIC(). If SET_SSV has not been successfully called, attempts to emit tokens MUST fail.

クライアントは、SSV GSSコンテキストを使用してGSS_WRAP()およびGSS_GETMIC()からトークンをエミッでエミッタリングできる前にSET_SSVを介してSSVを確立する必要があります。set_ssvが正常に呼び出されていない場合、トークンをエミッタエミッタを発行しようとする必要があります。

The SSV mechanism does not support replay detection and sequencing in its tokens because RPCSEC_GSS does not use those features (see "Context Creation Requests", Section 5.2.2 of [4]). However, Section 2.10.10 discusses special considerations for the SSV mechanism when used with RPCSEC_GSS.


2.10.10. Security Considerations for RPCSEC_GSS When Using the SSV Mechanism

2.10.10. SSVメカニズムを使用するときのRPCSEC_GSSのセキュリティ上の考慮事項

When a client ID is created with SP4_SSV state protection (see Section 18.35), the client is permitted to associate multiple RPCSEC_GSS handles with the single SSV GSS context (see Section 2.10.9). Because of the way RPCSEC_GSS (both version 1 and version 2, see [4] and [9]) calculate the verifier of the reply, special care must be taken by the implementation of the NFSv4.1 client to prevent attacks by a man-in-the-middle. The verifier of an RPCSEC_GSS reply is the output of GSS_GetMIC() applied to the input value of the seq_num field of the RPCSEC_GSS credential (data type rpc_gss_cred_ver_1_t) (see Section of [4]). If multiple RPCSEC_GSS handles share the same GSS context, then if one handle is used to send a request with the same seq_num value as another handle, an attacker could block the reply, and replace it with the verifier used for the other handle.

クライアントIDがSP4_SSV状態保護(セクション18.35を参照)で作成されると、クライアントは複数のRPCSEC_GSSハンドルを単一のSSV GSSコンテキストに関連付けることができます(セクション2.10.9を参照)。rpcsec_gss(バージョン1とバージョン2の両方、[4]、[9])の計算は、返信の検証を計算する必要があります。マンによる攻撃を防ぐためのNFSV4.1クライアントの実装によって考慮する必要があります。途中で。RPCSEC_GSS応答の検証者は、RPCSEC_GSSクレデンシャル(データ型RPC_GSS_CRED_VER__1_T)のSEQ_NUMフィールドの入力値に適用されるGSS_GETMIC()の出力です([4]のセクション5.3.3.2を参照)。複数のRPCSEC_GSSが同じGSSコンテキストを共有する場合、1つのハンドルを使用して同じSEQNUM値を別のハンドルとして要求を送信する場合、攻撃者は返信をブロックし、もう一方のハンドルに使用される検証者に置き換えることができます。

There are multiple ways to prevent the attack on the SSV RPCSEC_GSS verifier in the reply. The simplest is believed to be as follows.

返信でSSV RPCSEC_GSS検証者に対する攻撃を防ぐ方法は複数あります。最も単純なものは以下の通りであると考えられています。

* Each time one or more new SSV RPCSEC_GSS handles are created via EXCHANGE_ID, the client SHOULD send a SET_SSV operation to modify the SSV. By changing the SSV, the new handles will not result in the re-use of an SSV RPCSEC_GSS verifier in a reply.

* 1つ以上の新しいSSV RPCSEC_GSSハンドルがExchange_IDを介して作成されるたびに、クライアントはSSVを変更するためのset_ssv操作を送信する必要があります。SSVを変更することで、新しいハンドルは応答のSSV RPCSEC_GSS検証者の再利用をもたらされません。

* When a requester decides to use N SSV RPCSEC_GSS handles, it SHOULD assign a unique and non-overlapping range of seq_nums to each SSV RPCSEC_GSS handle. The size of each range SHOULD be equal to MAXSEQ / N (see Section 5 of [4] for the definition of MAXSEQ). When an SSV RPCSEC_GSS handle reaches its maximum, it SHOULD force the replier to destroy the handle by sending a NULL RPC request with seq_num set to MAXSEQ + 1 (see Section of [4]).

* リクエスターがNSV RPCSEC_GSSハンドルを使用することを決定すると、各SSV RPCSEC_GSSハンドルにSEQNUMSの一意の範囲と重複しない範囲を割り当てる必要があります。各範囲のサイズはmaxseq / nに等しくなければなりません(MaxSeqの定義については[4]のセクション5を参照)。SSV RPCSEC_GSSハンドルが最大に達すると、SEQNUMをMAXSQ 1に設定してNULL RPC要求を送信することで、リプライアにハンドルを破棄するように強制する必要があります([4]のセクション5.3.3.3を参照)。

* When the requester wants to increase or decrease N, it SHOULD force the replier to destroy all N handles by sending a NULL RPC request on each handle with seq_num set to MAXSEQ + 1. If the requester is the client, it SHOULD send a SET_SSV operation before using new handles. If the requester is the server, then the client SHOULD send a SET_SSV operation when it detects that the server has forced it to destroy a backchannel's SSV RPCSEC_GSS handle. By sending a SET_SSV operation, the SSV will change, and so the attacker will be unavailable to successfully replay a previous verifier in a reply to the requester.

* リクエスタがNを増減したい場合はNを増減したい場合は、SEQ_NUMをMAXSEQに設定して各ハンドルでNULL RPC要求を送信することで、すべてのNハンドルを破壊する必要があります.1がクライアントである場合は、前にset_ssv操作を送信する必要があります。新しいハンドルを使うリクエスタがサーバーの場合、サーバーがBackChannelのSSV RPCSEC_GSSハンドルを破棄するように強制したことを検出すると、クライアントはset_ssv操作を送信する必要があります。set_ssv操作を送信することによって、SSVは変更され、攻撃者は要求者への返信で前の検証者を正常に再生することができません。

Note that if the replier carefully creates the SSV RPCSEC_GSS handles, the related risk of a man-in-the-middle splicing a forged SSV RPCSEC_GSS credential with a verifier for another handle does not exist. This is because the verifier in an RPCSEC_GSS request is computed from input that includes both the RPCSEC_GSS handle and seq_num (see Section 5.3.1 of [4]). Provided the replier takes care to avoid re-using the value of an RPCSEC_GSS handle that it creates, such as by including a generation number in the handle, the man-in-the-middle will not be able to successfully replay a previous verifier in the request to a replier.

ReplierがSSV RPCSEC_GSSハンドルを慎重に作成した場合、中間のSSV RPCSEC_GSSクレデンシャルが別のハンドルの検証者に登録されているMAN-IN-MIDDE SSV RPCSEC_GSSクレデンシャルの関連リスクが存在しません。これは、RPCSEC_GSS要求の検証者がRPCSEC_GSSハンドルとSEQ_NUMの両方を含む入力から計算されるためです([4]のセクション5.3.1を参照)。Replierが、ハンドル内の世代番号を含めるなど、作成したRPCSEC_GSSハンドルの値を再利用しないように注意してください。中央のMAN-IN-THE-THE-THE-THE-THE-THE-THE-THE-THE-THE-THE-THE-THE-THE-THE-THE-THE-THE-THE-MODINDが、以前の検証者を再生できなくなります。専用の要求

2.10.11. Session Mechanics - Steady State
2.10.11. セッションメカニズム - 定常状態 Obligations of the Server サーバーの義務

The server has the primary obligation to monitor the state of backchannel resources that the client has created for the server (RPCSEC_GSS contexts and backchannel connections). If these resources vanish, the server takes action as specified in Section

サーバーには、クライアントがサーバー用に作成したバックチャネルリソースの状態を監視する主な義務があります(RPCSEC_GSSコンテキストとバックチャネル接続)。これらのリソースが消えた場合、サーバーはセクション2.10.13.2で指定されているようにアクションを実行します。 Obligations of the Client クライアントの義務

The client SHOULD honor the following obligations in order to utilize the session:


* Keep a necessary session from going idle on the server. A client that requires a session but nonetheless is not sending operations risks having the session be destroyed by the server. This is because sessions consume resources, and resource limitations may force the server to cull an inactive session. A server MAY consider a session to be inactive if the client has not used the session before the session inactivity timer (Section 2.10.12) has expired.

* サーバー上のアイドル状態から必要なセッションを保持してください。セッションを必要とするが、それにもかかわらず、セッションを送信するリスクを送信していないクライアントは、サーバによって破棄されない。これは、セッションがリソースを消費するため、リソースの制限により、サーバーが非アクティブセッションを強制的に解凍する可能性があります。クライアントがセッション非アクティブタイマー(セクション2.10.12)が期限切れになった前に、クライアントがセッションを使用していない場合、サーバーが非アクティブになることを検討することがあります。

* Destroy the session when not needed. If a client has multiple sessions, one of which has no requests waiting for replies, and has been idle for some period of time, it SHOULD destroy the session.

* 必要ないときにセッションを破壊する。クライアントに複数のセッションがある場合、そのうちの1つは返信を待っていて、何らかの期間アイドル状態になっているため、セッションを破棄する必要があります。

* Maintain GSS contexts and RPCSEC_GSS handles for the backchannel. If the client requires the server to use the RPCSEC_GSS security flavor for callbacks, then it needs to be sure the RPCSEC_GSS handles and/or their GSS contexts that are handed to the server via BACKCHANNEL_CTL or CREATE_SESSION are unexpired.

* BackChannelのGSSコンテキストとRPCSEC_GSSハンドルを維持します。クライアントにコールバックのRPCSEC_GSSセキュリティフレーバーを使用するようにする必要がある場合は、rpcsec_gssがbackchannel_ctlまたはcreate_sessionを経過してサーバーに渡されるRPCSEC_GSSがハンドルおよび/またはそれらのGSSコンテキストがないことを確認する必要があります。

* Preserve a connection for a backchannel. The server requires a backchannel in order to gracefully recall recallable state or notify the client of certain events. Note that if the connection is not being used for the fore channel, there is no way for the client to tell if the connection is still alive (e.g., the server restarted without sending a disconnect). The onus is on the server, not the client, to determine if the backchannel's connection is alive, and to indicate in the response to a SEQUENCE operation when the last connection associated with a session's backchannel has disconnected.

* バックチャネルの接続を保持します。サーバーには、リコール可能な状態を正しくリコールしたり、特定のイベントのクライアントに通知するためにバックチャネルが必要です。接続が前のチャネルに使用されていない場合、クライアントが接続がまだ生存しているかどうか(例えば、切断を送信せずにサーバーが再起動された場合)に指示する方法はありません。ONUSは、バックチャネルの接続が生きているかどうかを判断し、セッションのBackChannelに関連付けられている最後の接続が切断されたときに、シーケンス操作への応答を示すために、クライアントではなくサーバー上にあります。 Steps the Client Takes to Establish a Session ステップクライアントがセッションを確立するのにかかるステップ

If the client does not have a client ID, the client sends EXCHANGE_ID to establish a client ID. If it opts for SP4_MACH_CRED or SP4_SSV protection, in the spo_must_enforce list of operations, it SHOULD at minimum specify CREATE_SESSION, DESTROY_SESSION, BIND_CONN_TO_SESSION, BACKCHANNEL_CTL, and DESTROY_CLIENTID. If it opts for SP4_SSV protection, the client needs to ask for SSV-based RPCSEC_GSS handles.


The client uses the client ID to send a CREATE_SESSION on a connection to the server. The results of CREATE_SESSION indicate whether or not the server will persist the session reply cache through a server that has restarted, and the client notes this for future reference.


If the client specified SP4_SSV state protection when the client ID was created, then it SHOULD send SET_SSV in the first COMPOUND after the session is created. Each time a new principal goes to use the client ID, it SHOULD send a SET_SSV again.


If the client wants to use delegations, layouts, directory notifications, or any other state that requires a backchannel, then it needs to add a connection to the backchannel if CREATE_SESSION did not already do so. The client creates a connection, and calls BIND_CONN_TO_SESSION to associate the connection with the session and the session's backchannel. If CREATE_SESSION did not already do so, the client MUST tell the server what security is required in order for the client to accept callbacks. The client does this via BACKCHANNEL_CTL. If the client selected SP4_MACH_CRED or SP4_SSV protection when it called EXCHANGE_ID, then the client SHOULD specify that the backchannel use RPCSEC_GSS contexts for security.


If the client wants to use additional connections for the backchannel, then it needs to call BIND_CONN_TO_SESSION on each connection it wants to use with the session. If the client wants to use additional connections for the fore channel, then it needs to call BIND_CONN_TO_SESSION if it specified SP4_SSV or SP4_MACH_CRED state protection when the client ID was created.

クライアントがBackChannelに追加の接続を使用したい場合は、セッションで使用する必要がある接続ごとにBIND_CONN_TO_SESSIONを呼び出す必要があります。クライアントがFore Channelに追加の接続を使用したい場合は、クライアントIDが作成されたときにSP4_SSVまたはSP4_MACH_CRED状態保護を指定した場合、BIND_CONN_TO_SESSISTを呼び出す必要があります。

At this point, the session has reached steady state.


2.10.12. Session Inactivity Timer
2.10.12. セッション非アクティブタイマー

The server MAY maintain a session inactivity timer for each session. If the session inactivity timer expires, then the server MAY destroy the session. To avoid losing a session due to inactivity, the client MUST renew the session inactivity timer. The length of session inactivity timer MUST NOT be less than the lease_time attribute (Section As with lease renewal (Section 8.3), when the server receives a SEQUENCE operation, it resets the session inactivity timer, and MUST NOT allow the timer to expire while the rest of the operations in the COMPOUND procedure's request are still executing. Once the last operation has finished, the server MUST set the session inactivity timer to expire no sooner than the sum of the current time and the value of the lease_time attribute.


2.10.13. Session Mechanics - Recovery
2.10.13. セッションの力学 - 回復 Events Requiring Client Action クライアントアクションを必要とするイベント

The following events require client action to recover.

次のイベントには、クライアントアクションが回復する必要があります。 RPCSEC_GSS Context Loss by Callback Path コールバックパスによるRPCSEC_GSSコンテキスト損失

If all RPCSEC_GSS handles granted by the client to the server for callback use have expired, the client MUST establish a new handle via BACKCHANNEL_CTL. The sr_status_flags field of the SEQUENCE results indicates when callback handles are nearly expired, or fully expired (see Section 18.46.3).

コールバック使用のためにクライアントによって許可されたすべてのRPCSEC_GSSハンドルが期限切れになっている場合、クライアントはbackchannel_ctlを介して新しいハンドルを確立する必要があります。シーケンスの結果のsr_status_flagsフィールドは、コールバックハンドルがほぼ期限切れになっているか完全に期限切れになっているかを示します(セクション18.46.3を参照)。 Connection Loss 接続損失

If the client loses the last connection of the session and wants to retain the session, then it needs to create a new connection, and if, when the client ID was created, BIND_CONN_TO_SESSION was specified in the spo_must_enforce list, the client MUST use BIND_CONN_TO_SESSION to associate the connection with the session.


If there was a request outstanding at the time of connection loss, then if the client wants to continue to use the session, it MUST retry the request, as described in Section Note that it is not necessary to retry requests over a connection with the same source network address or the same destination network address as the lost connection. As long as the session ID, slot ID, and sequence ID in the retry match that of the original request, the server will recognize the request as a retry if it executed the request prior to disconnect.


If the connection that was lost was the last one associated with the backchannel, and the client wants to retain the backchannel and/or prevent revocation of recallable state, the client needs to reconnect, and if it does, it MUST associate the connection to the session and backchannel via BIND_CONN_TO_SESSION. The server SHOULD indicate when it has no callback connection via the sr_status_flags result from SEQUENCE.

失われた接続がBackChannelに関連付けられていて、クライアントがバックチャネルを保持し、リコール可能な状態の失効を防ぐことを望んでいる場合、クライアントは再接続する必要があります。そうすれば、その接続を関連付ける必要があります。bind_conn_to_sessionを介したセッションとバックチャネル。サーバーは、SR_STATUS_FLAGSを介したコールバック接続がシーケンスから発生しない場合に指定する必要があります。 Backchannel GSS Context Loss BackChannel GSSのコンテキストの損失

Via the sr_status_flags result of the SEQUENCE operation or other means, the client will learn if some or all of the RPCSEC_GSS contexts it assigned to the backchannel have been lost. If the client wants to retain the backchannel and/or not put recallable state subject to revocation, the client needs to use BACKCHANNEL_CTL to assign new contexts.

シーケンス操作または他の手段のSR_STATUS_FLAGSの結果を介して、クライアントはバックチャネルに割り当てられたRPCSEC_GSSコンテキストの一部または全部が失われた場合に学習されます。クライアントがバックチャネルを保持したり、リコール可能な状態を失効したりしない場合、クライアントはBackChannel_CTLを使用して新しいコンテキストを割り当てる必要があります。 Loss of Session セッションの損失

The replier might lose a record of the session. Causes include:


* Replier failure and restart.

* リプライアの障害と再起動

* A catastrophe that causes the reply cache to be corrupted or lost on the media on which it was stored. This applies even if the replier indicated in the CREATE_SESSION results that it would persist the cache.

* それが保存されたメディアで応答キャッシュを破損または失われるようにする大惨事。これは、CREATE_SESSIONに示されているレプリアがキャッシュを永続化した場合にも適用されます。

* The server purges the session of a client that has been inactive for a very extended period of time.

* サーバーは、非常に長い期間非アクティブであるクライアントのセッションを消去します。

* As a result of configuration changes among a set of clustered servers, a network address previously connected to one server becomes connected to a different server that has no knowledge of the session in question. Such a configuration change will generally only happen when the original server ceases to function for a time.

* 一組のクラスタサーバ間の構成変更の結果として、1つのサーバに以前に接続されているネットワークアドレスが、問題のセッションに関する知識を持たない異なるサーバに接続される。そのような構成変更は、一般に、元のサーバが一度に機能しなくなるとしか起こりません。

Loss of reply cache is equivalent to loss of session. The replier indicates loss of session to the requester by returning NFS4ERR_BADSESSION on the next operation that uses the session ID that refers to the lost session.


After an event like a server restart, the client may have lost its connections. The client assumes for the moment that the session has not been lost. It reconnects, and if it specified connection association enforcement when the session was created, it invokes BIND_CONN_TO_SESSION using the session ID. Otherwise, it invokes SEQUENCE. If BIND_CONN_TO_SESSION or SEQUENCE returns NFS4ERR_BADSESSION, the client knows the session is not available to it when communicating with that network address. If the connection survives session loss, then the next SEQUENCE operation the client sends over the connection will get back NFS4ERR_BADSESSION. The client again knows the session was lost.


Here is one suggested algorithm for the client when it gets NFS4ERR_BADSESSION. It is not obligatory in that, if a client does not want to take advantage of such features as trunking, it may omit parts of it. However, it is a useful example that draws attention to various possible recovery issues:


1. If the client has other connections to other server network addresses associated with the same session, attempt a COMPOUND with a single operation, SEQUENCE, on each of the other connections.

1. クライアントが同じセッションに関連付けられている他のサーバーネットワークアドレスへの他の接続を持っている場合は、他の各接続で単一の操作、シーケンスを持つ複合を試みます。

2. If the attempts succeed, the session is still alive, and this is a strong indicator that the server's network address has moved. The client might send an EXCHANGE_ID on the connection that returned NFS4ERR_BADSESSION to see if there are opportunities for client ID trunking (i.e., the same client ID and so_major_id value are returned). The client might use DNS to see if the moved network address was replaced with another, so that the performance and availability benefits of session trunking can continue.

2. 試行が成功した場合、セッションはまだ生きていますが、これはサーバーのネットワークアドレスが移動した強力なインジケータです。クライアントは、クライアントIDのトランキングの機会があるかどうかを確認するためにNFS4ERR_BADSessionを返す接続にExchange_idを送信することができます(すなわち、同じクライアントIDとSO_MAJOR_ID値が返される)。クライアントはDNSを使用して、移動したネットワークアドレスが別のネットワークアドレスに置き換えられたかどうかを確認することができ、セッションのトランキングのパフォーマンスと可用性の利点が続くことができます。

3. If the SEQUENCE requests fail with NFS4ERR_BADSESSION, then the session no longer exists on any of the server network addresses for which the client has connections associated with that session ID. It is possible the session is still alive and available on other network addresses. The client sends an EXCHANGE_ID on all the connections to see if the server owner is still listening on those network addresses. If the same server owner is returned but a new client ID is returned, this is a strong indicator of a server restart. If both the same server owner and same client ID are returned, then this is a strong indication that the server did delete the session, and the client will need to send a CREATE_SESSION if it has no other sessions for that client ID. If a different server owner is returned, the client can use DNS to find other network addresses. If it does not, or if DNS does not find any other addresses for the server, then the client will be unable to provide NFSv4.1 service, and fatal errors should be returned to processes that were using the server. If the client is using a "mount" paradigm, unmounting the server is advised.

3. シーケンス要求がNFS4ERR_BADSessionで失敗した場合、そのセッションIDに関連付けられている接続が関連付けられているサーバーネットワークアドレスのいずれかにセッションが存在しなくなりました。セッションがまだ生きていて他のネットワークアドレスで利用可能である可能性があります。クライアントは、サーバーの所有者がそれらのネットワークアドレスを依然として待機しているかどうかを確認するために、すべての接続でExchange_idを送信します。同じサーバーの所有者が返されたが新しいクライアントIDが返された場合、これはサーバーの再起動の強力なインジケータです。同じサーバーの所有者と同じクライアントIDの両方が返された場合、これはサーバーがセッションを削除したという強力な表示であり、クライアントはそのクライアントIDのセッションが他にある場合はcreate_sessionを送信する必要があります。別のサーバーの所有者が返された場合、クライアントはDNSを使用して他のネットワークアドレスを見つけることができます。そうでない場合、またはDNSがサーバーの他のアドレスが見つからない場合、クライアントはNFSV4.1サービスを提供できなくなり、致命的なエラーはサーバーを使用していたプロセスに返されるべきです。クライアントが「マウント」パラダイムを使用している場合は、サーバーをマウント解除します。

4. If the client knows of no other connections associated with the session ID and server network addresses that are, or have been, associated with the session ID, then the client can use DNS to find other network addresses. If it does not, or if DNS does not find any other addresses for the server, then the client will be unable to provide NFSv4.1 service, and fatal errors should be returned to processes that were using the server. If the client is using a "mount" paradigm, unmounting the server is advised.

4. クライアントがセッションIDとサーバーネットワークアドレスと関連付けられている、またはセッションIDに関連付けられている他の接続を知っていない場合、クライアントはDNSを使用して他のネットワークアドレスを見つけることができます。そうでない場合、またはDNSがサーバーの他のアドレスが見つからない場合、クライアントはNFSV4.1サービスを提供できなくなり、致命的なエラーはサーバーを使用していたプロセスに返されるべきです。クライアントが「マウント」パラダイムを使用している場合は、サーバーをマウント解除します。

If there is a reconfiguration event that results in the same network address being assigned to servers where the eir_server_scope value is different, it cannot be guaranteed that a session ID generated by the first will be recognized as invalid by the first. Therefore, in managing server reconfigurations among servers with different server scope values, it is necessary to make sure that all clients have disconnected from the first server before effecting the reconfiguration. Nonetheless, clients should not assume that servers will always adhere to this requirement; clients MUST be prepared to deal with unexpected effects of server reconfigurations. Even where a session ID is inappropriately recognized as valid, it is likely either that the connection will not be recognized as valid or that a sequence value for a slot will not be correct. Therefore, when a client receives results indicating such unexpected errors, the use of EXCHANGE_ID to determine the current server configuration is RECOMMENDED.


A variation on the above is that after a server's network address moves, there is no NFSv4.1 server listening, e.g., no listener on port 2049. In this example, one of the following occur: the NFSv4 server returns NFS4ERR_MINOR_VERS_MISMATCH, the NFS server returns a PROG_MISMATCH error, the RPC listener on 2049 returns PROG_UNVAIL, or attempts to reconnect to the network address timeout. These SHOULD be treated as equivalent to SEQUENCE returning NFS4ERR_BADSESSION for these purposes.


When the client detects session loss, it needs to call CREATE_SESSION to recover. Any non-idempotent operations that were in progress might have been performed on the server at the time of session loss. The client has no general way to recover from this.


Note that loss of session does not imply loss of byte-range lock, open, delegation, or layout state because locks, opens, delegations, and layouts are tied to the client ID and depend on the client ID, not the session. Nor does loss of byte-range lock, open, delegation, or layout state imply loss of session state, because the session depends on the client ID; loss of client ID however does imply loss of session, byte-range lock, open, delegation, and layout state. See Section 8.4.2. A session can survive a server restart, but lock recovery may still be needed.


It is possible that CREATE_SESSION will fail with NFS4ERR_STALE_CLIENTID (e.g., the server restarts and does not preserve client ID state). If so, the client needs to call EXCHANGE_ID, followed by CREATE_SESSION.

CREATE_SESSIONがNFS4ERR_STALE_CLIENTIDで失敗する可能性があります(たとえば、サーバーはクライアントID状態を再起動し、保存しません)。もしそうなら、クライアントはExchange_idを呼び出してcreate_sessionを呼び出します。 Events Requiring Server Action サーバーアクションを必要とするイベント

The following events require server action to recover.

次のイベントには、サーバーアクションが回復する必要があります。 Client Crash and Restart クライアントがクラッシュして再起動します

As described in Section 18.35, a restarted client sends EXCHANGE_ID in such a way that it causes the server to delete any sessions it had.

セクション18.35で説明されているように、再起動したクライアントは、サーバーに持っていたセッションを削除するようにExchange_IDを送信します。 Client Crash with No Restart 再起動なしのクライアントクラッシュ

If a client crashes and never comes back, it will never send EXCHANGE_ID with its old client owner. Thus, the server has session state that will never be used again. After an extended period of time, and if the server has resource constraints, it MAY destroy the old session as well as locking state.

クライアントがクラッシュして戻ってきたことがない場合、それは古いクライアント所有者とExchange_idを送信することはありません。したがって、サーバーはセッション状態になります。長期間にわたって、サーバーがリソース制約を持っている場合、ロック状態だけでなく古いセッションも破棄される可能性があります。 Extended Network Partition 拡張ネットワークパーティション

To the server, the extended network partition may be no different from a client crash with no restart (see Section Unless the server can discern that there is a network partition, it is free to treat the situation as if the client has crashed permanently.

サーバーに、拡張ネットワークパーティションは再起動なしでクライアントクラッシュと変わらない可能性があります(セクション2.を参照)。サーバーがネットワークパーティションがあることを見分けることができない限り、クライアントが永久にクラッシュしたかのように状況を自由に扱うことは自由です。 Backchannel Connection Loss バックチャンネル接続損失

If there were callback requests outstanding at the time of a connection loss, then the server MUST retry the requests, as described in Section Note that it is not necessary to retry requests over a connection with the same source network address or the same destination network address as the lost connection. As long as the session ID, slot ID, and sequence ID in the retry match that of the original request, the callback target will recognize the request as a retry even if it did see the request prior to disconnect.


If the connection lost is the last one associated with the backchannel, then the server MUST indicate that in the sr_status_flags field of every SEQUENCE reply until the backchannel is re-established. There are two situations, each of which uses different status flags: no connectivity for the session's backchannel and no connectivity for any session backchannel of the client. See Section 18.46 for a description of the appropriate flags in sr_status_flags.

接続がBackChannelに関連付けられている最後のものが失われた場合、サーバーはバックチャネルが再確立されるまですべてのシーケンス応答のSR_STATUS_FLAGSフィールドにそれを示す必要があります。それぞれが異なるステータスフラグを使用している2つの状況があります。セッションのBackChannelの接続はありません。クライアントのセッションバックチャンネルの接続はありません。SR_STATUS_FLAGSの適切なフラグの説明については、セクション18.46を参照してください。 GSS Context Loss GSSのコンテキスト損失

The server SHOULD monitor when the number of RPCSEC_GSS handles assigned to the backchannel reaches one, and when that one handle is near expiry (i.e., between one and two periods of lease time), and indicate so in the sr_status_flags field of all SEQUENCE replies. The server MUST indicate when all of the backchannel's assigned RPCSEC_GSS handles have expired via the sr_status_flags field of all SEQUENCE replies.


2.10.14. Parallel NFS and Sessions
2.10.14. 並列NFSとセッション

A client and server can potentially be a non-pNFS implementation, a metadata server implementation, a data server implementation, or two or three types of implementations. The EXCHGID4_FLAG_USE_NON_PNFS, EXCHGID4_FLAG_USE_PNFS_MDS, and EXCHGID4_FLAG_USE_PNFS_DS flags (not mutually exclusive) are passed in the EXCHANGE_ID arguments and results to allow the client to indicate how it wants to use sessions created under the client ID, and to allow the server to indicate how it will allow the sessions to be used. See Section 13.1 for pNFS sessions considerations.


3. Protocol Constants and Data Types
3. プロトコル定数とデータ型

The syntax and semantics to describe the data types of the NFSv4.1 protocol are defined in the XDR (RFC 4506 [2]) and RPC (RFC 5531 [3]) documents. The next sections build upon the XDR data types to define constants, types, and structures specific to this protocol. The full list of XDR data types is in [10].

NFSV4.1プロトコルのデータ型を記述するための構文とセマンティクスは、XDR(RFC 4506 [2])とRPC(RFC 5531 [3])の文書で定義されています。次のセクションは、このプロトコルに固有の定数、型、および構造を定義するためにXDRデータ型の上に構築されます。XDRデータ型の全リストは[10]にあります。

3.1. Basic Constants
3.1. 基本定数
   const NFS4_FHSIZE               = 128;
   const NFS4_VERIFIER_SIZE        = 8;
   const NFS4_OPAQUE_LIMIT         = 1024;
   const NFS4_SESSIONID_SIZE       = 16;
   const NFS4_INT64_MAX            = 0x7fffffffffffffff;
   const NFS4_UINT64_MAX           = 0xffffffffffffffff;
   const NFS4_INT32_MAX            = 0x7fffffff;
   const NFS4_UINT32_MAX           = 0xffffffff;
   const NFS4_MAXFILELEN           = 0xffffffffffffffff;
   const NFS4_MAXFILEOFF           = 0xfffffffffffffffe;

Except where noted, all these constants are defined in bytes.


* NFS4_FHSIZE is the maximum size of a filehandle.

* NFS4_FHSIZEはファイルハンドルの最大サイズです。

* NFS4_VERIFIER_SIZE is the fixed size of a verifier.

* NFS4_VERIFIER_SIZEは、検証者の固定サイズです。

* NFS4_OPAQUE_LIMIT is the maximum size of certain opaque information.

* NFS4_OPAQUE_LIMITは、特定の不透明情報の最大サイズです。

* NFS4_SESSIONID_SIZE is the fixed size of a session identifier.

* NFS4_SESSIONID_SIZEはセッション識別子の固定サイズです。

* NFS4_INT64_MAX is the maximum value of a signed 64-bit integer.

* NFS4_INT64_MAXは符号付き64ビット整数の最大値です。

* NFS4_UINT64_MAX is the maximum value of an unsigned 64-bit integer.

* NFS4_UINT64_MAXは、符号なし64ビット整数の最大値です。

* NFS4_INT32_MAX is the maximum value of a signed 32-bit integer.

* NFS4_INT32_MAXは符号付き32ビット整数の最大値です。

* NFS4_UINT32_MAX is the maximum value of an unsigned 32-bit integer.

* NFS4_UINT32_MAXは、符号なし32ビット整数の最大値です。

* NFS4_MAXFILELEN is the maximum length of a regular file.

* NFS4_MAXFILELENは、通常のファイルの最大長です。

* NFS4_MAXFILEOFF is the maximum offset into a regular file.

* NFS4_MAXFILEOFFは、通常のファイルへの最大オフセットです。

3.2. Basic Data Types
3.2. 基本データ型

These are the base NFSv4.1 data types.


     | Data Type     | Definition                                   |
     | int32_t       | typedef int int32_t;                         |
     | uint32_t      | typedef unsigned int uint32_t;               |
     | int64_t       | typedef hyper int64_t;                       |
     | uint64_t      | typedef unsigned hyper uint64_t;             |
     | attrlist4     | typedef opaque attrlist4<>;                  |
     |               |                                              |
     |               | Used for file/directory attributes.          |
     | bitmap4       | typedef uint32_t bitmap4<>;                  |
     |               |                                              |
     |               | Used in attribute array encoding.            |
     | changeid4     | typedef uint64_t changeid4;                  |
     |               |                                              |
     |               | Used in the definition of change_info4.      |
     | clientid4     | typedef uint64_t clientid4;                  |
     |               |                                              |
     |               | Shorthand reference to client                |
     |               | identification.                              |
     | count4        | typedef uint32_t count4;                     |
     |               |                                              |
     |               | Various count parameters (READ, WRITE,       |
     |               | COMMIT).                                     |
     | length4       | typedef uint64_t length4;                    |
     |               |                                              |
     |               | The length of a byte-range within a file.    |
     | mode4         | typedef uint32_t mode4;                      |
     |               |                                              |
     |               | Mode attribute data type.                    |
     | nfs_cookie4   | typedef uint64_t nfs_cookie4;                |
     |               |                                              |
     |               | Opaque cookie value for READDIR.             |
     | nfs_fh4       | typedef opaque nfs_fh4<NFS4_FHSIZE>;         |
     |               |                                              |
     |               | Filehandle definition.                       |
     | nfs_ftype4    | enum nfs_ftype4;                             |
     |               |                                              |
     |               | Various defined file types.                  |
     | nfsstat4      | enum nfsstat4;                               |
     |               |                                              |
     |               | Return value for operations.                 |
     | offset4       | typedef uint64_t offset4;                    |
     |               |                                              |
     |               | Various offset designations (READ, WRITE,    |
     |               | LOCK, COMMIT).                               |
     | qop4          | typedef uint32_t qop4;                       |
     |               |                                              |
     |               | Quality of protection designation in         |
     |               | SECINFO.                                     |
     | sec_oid4      | typedef opaque sec_oid4<>;                   |
     |               |                                              |
     |               | Security Object Identifier.  The sec_oid4    |
     |               | data type is not really opaque.  Instead, it |
     |               | contains an ASN.1 OBJECT IDENTIFIER as used  |
     |               | by GSS-API in the mech_type argument to      |
     |               | GSS_Init_sec_context.  See [7] for details.  |
     | sequenceid4   | typedef uint32_t sequenceid4;                |
     |               |                                              |
     |               | Sequence number used for various session     |
     |               | operations (EXCHANGE_ID, CREATE_SESSION,     |
     |               | SEQUENCE, CB_SEQUENCE).                      |
     | seqid4        | typedef uint32_t seqid4;                     |
     |               |                                              |
     |               | Sequence identifier used for locking.        |
     | sessionid4    | typedef opaque                               |
     |               | sessionid4[NFS4_SESSIONID_SIZE];             |
     |               |                                              |
     |               | Session identifier.                          |
     | slotid4       | typedef uint32_t slotid4;                    |
     |               |                                              |
     |               | Sequencing artifact for various session      |
     |               | operations (SEQUENCE, CB_SEQUENCE).          |
     | utf8string    | typedef opaque utf8string<>;                 |
     |               |                                              |
     |               | UTF-8 encoding for strings.                  |
     | utf8str_cis   | typedef utf8string utf8str_cis;              |
     |               |                                              |
     |               | Case-insensitive UTF-8 string.               |
     | utf8str_cs    | typedef utf8string utf8str_cs;               |
     |               |                                              |
     |               | Case-sensitive UTF-8 string.                 |
     | utf8str_mixed | typedef utf8string utf8str_mixed;            |
     |               |                                              |
     |               | UTF-8 strings with a case-sensitive prefix   |
     |               | and a case-insensitive suffix.               |
     | component4    | typedef utf8str_cs component4;               |
     |               |                                              |
     |               | Represents pathname components.              |
     | linktext4     | typedef utf8str_cs linktext4;                |
     |               |                                              |
     |               | Symbolic link contents ("symbolic link" is   |
     |               | defined in an Open Group [Section 3.372 of Chapter 3 of Base Definitions of The Open Group Base Specifications Issue 6 IEEE Std 1003.1, 2004 Edition, HTML Version"">11] standard).     |
     | pathname4     | typedef component4 pathname4<>;              |
     |               |                                              |
     |               | Represents pathname for fs_locations.        |
     | verifier4     | typedef opaque                               |
     |               | verifier4[NFS4_VERIFIER_SIZE];               |
     |               |                                              |
     |               | Verifier used for various operations         |
     |               | (COMMIT, CREATE, EXCHANGE_ID, OPEN, READDIR, |
     |               | WRITE) NFS4_VERIFIER_SIZE is defined as 8.   |

Table 1


End of Base Data Types


3.3. Structured Data Types
3.3. 構造化データ型
3.3.1. nfstime4
3.3.1. nfstime4
   struct nfstime4 {
           int64_t         seconds;
           uint32_t        nseconds;

The nfstime4 data type gives the number of seconds and nanoseconds since midnight or zero hour January 1, 1970 Coordinated Universal Time (UTC). Values greater than zero for the seconds field denote dates after the zero hour January 1, 1970. Values less than zero for the seconds field denote dates before the zero hour January 1, 1970. In both cases, the nseconds field is to be added to the seconds field for the final time representation. For example, if the time to be represented is one-half second before zero hour January 1, 1970, the seconds field would have a value of negative one (-1) and the nseconds field would have a value of one-half second (500000000). Values greater than 999,999,999 for nseconds are invalid.


This data type is used to pass time and date information. A server converts to and from its local representation of time when processing time values, preserving as much accuracy as possible. If the precision of timestamps stored for a file system object is less than defined, loss of precision can occur. An adjunct time maintenance protocol is RECOMMENDED to reduce client and server time skew.

このデータ型は、時間と日付情報を渡すために使用されます。サーバーは、時間の値を処理するときのそのローカル表現との間で、できるだけ多くの精度を保持します。ファイルシステムオブジェクトに格納されているタイムスタンプの精度が定義されていない場合は、精度の損失が発生する可能性があります。クライアントとサーバーの時間のスキューを減らすには、ADJUNCT TIMEメンテナンスプロトコルを推奨します。

3.3.2. time_how4
3.3.2. time_how4.
   enum time_how4 {
           SET_TO_SERVER_TIME4 = 0,
           SET_TO_CLIENT_TIME4 = 1
3.3.3. settime4
3.3.3. settime4
   union settime4 switch (time_how4 set_it) {
            nfstime4       time;

The time_how4 and settime4 data types are used for setting timestamps in file object attributes. If set_it is SET_TO_SERVER_TIME4, then the server uses its local representation of time for the time value.


3.3.4. specdata4
3.3.4. SpecData4
   struct specdata4 {
    uint32_t specdata1; /* major device number */
    uint32_t specdata2; /* minor device number */

This data type represents the device numbers for the device file types NF4CHR and NF4BLK.


3.3.5. fsid4
3.3.5. FSID4
   struct fsid4 {
           uint64_t        major;
           uint64_t        minor;
3.3.6. change_policy4
3.3.6. change_policy4
   struct change_policy4 {
           uint64_t        cp_major;
           uint64_t        cp_minor;

The change_policy4 data type is used for the change_policy RECOMMENDED attribute. It provides change sequencing indication analogous to the change attribute. To enable the server to present a value valid across server re-initialization without requiring persistent storage, two 64-bit quantities are used, allowing one to be a server instance ID and the second to be incremented non-persistently, within a given server instance.


3.3.7. fattr4
3.3.7. Fattr4
   struct fattr4 {
           bitmap4         attrmask;
           attrlist4       attr_vals;

The fattr4 data type is used to represent file and directory attributes.


The bitmap is a counted array of 32-bit integers used to contain bit values. The position of the integer in the array that contains bit n can be computed from the expression (n / 32), and its bit within that integer is (n mod 32).

ビットマップは、ビット値を含むために使用される32ビット整数のカウントされた配列です。ビットNを含むアレイ内の整数の位置は、式(N / 32)から計算することができ、その整数内のそのビットは(n mod 32)である。

                     0            1
   |  count    | 31  ..  0 | 63  .. 32 |
3.3.8. change_info4
3.3.8. change_info4.
   struct change_info4 {
           bool            atomic;
           changeid4       before;
           changeid4       after;

This data type is used with the CREATE, LINK, OPEN, REMOVE, and RENAME operations to let the client know the value of the change attribute for the directory in which the target file system object resides.

このデータ型は、クライアントにターゲットファイルシステムオブジェクトが存在するディレクトリの変更属性の値をクライアントに知らせるために、Create、Link、Open、Remove、およびRename Operationsと共に使用されます。

3.3.9. netaddr4
3.3.9. NetAddr4.
   struct netaddr4 {
           /* see struct rpcb in RFC 1833 */
           string na_r_netid<>; /* network id */
           string na_r_addr<>;  /* universal address */

The netaddr4 data type is used to identify network transport endpoints. The na_r_netid and na_r_addr fields respectively contain a netid and uaddr. The netid and uaddr concepts are defined in [12]. The netid and uaddr formats for TCP over IPv4 and TCP over IPv6 are defined in [12], specifically Tables 2 and 3 and in Sections and

NetAddr4データ型は、ネットワークトランスポートエンドポイントを識別するために使用されます。NA_R_NETIDおよびNA_R_ADDRフィールドはそれぞれNETIDとUADDRを含みます。NETIDおよびUADDRの概念は[12]で定義されています。IPv4 over over IPv6 over over ipv6 over over tcpのNETIDおよびUADDRフォーマットは、[12]、具体的な表2および3およびセクション5.2.3.3および5.2.3.4で定義されています。

3.3.10. state_owner4
3.3.10. State_Owner4
   struct state_owner4 {
           clientid4       clientid;
           opaque          owner<NFS4_OPAQUE_LIMIT>;
   typedef state_owner4 open_owner4;
   typedef state_owner4 lock_owner4;

The state_owner4 data type is the base type for the open_owner4 (Section and lock_owner4 (Section

STATE_OWNER4データ型は、OPEN_OWNER4(セクション3.3.10.1)およびLOCK_OWNER4(セクション3.3.10.2)の基本タイプです。 open_owner4 open_owner4.

This data type is used to identify the owner of OPEN state.

このデータ型は、オープン状態の所有者を識別するために使用されます。 lock_owner4 lock_owner4

This structure is used to identify the owner of byte-range locking state.


3.3.11. open_to_lock_owner4
3.3.11. Open_To_Lock_Owner4.
   struct open_to_lock_owner4 {
           seqid4          open_seqid;
           stateid4        open_stateid;
           seqid4          lock_seqid;
           lock_owner4     lock_owner;

This data type is used for the first LOCK operation done for an open_owner4. It provides both the open_stateid and lock_owner, such that the transition is made from a valid open_stateid sequence to that of the new lock_stateid sequence. Using this mechanism avoids the confirmation of the lock_owner/lock_seqid pair since it is tied to established state in the form of the open_stateid/open_seqid.

このデータ型は、Open_owner4に対して行われた最初のロック操作に使用されます。遷移が有効なopen_stateIDシーケンスから新しいlock_stateIDシーケンスの遷移を行うように、open_stateIdとlock_ownerの両方を提供します。このメカニズムを使用すると、OPEN_STATEID / OPEN_SEQIDの形式で確立された状態に接続されているため、lock_owner / lock_seqidペアの確認を回避します。

3.3.12. stateid4
3.3.12. StateID4
   struct stateid4 {
           uint32_t        seqid;
           opaque          other[12];

This data type is used for the various state sharing mechanisms between the client and server. The client never modifies a value of data type stateid. The starting value of the "seqid" field is undefined. The server is required to increment the "seqid" field by one at each transition of the stateid. This is important since the client will inspect the seqid in OPEN stateids to determine the order of OPEN processing done by the server.

このデータ型は、クライアントとサーバー間のさまざまな状態共有メカニズムに使用されます。クライアントはデータ型StateIDの値を変更しません。「seqid」フィールドの開始値は未定義です。サーバーは、StareIDの各遷移時に「SEQID」フィールドを1つずつ増やす必要があります。クライアントがOpen StateIDのSEQIDを検査してサーバーによって行われたオープン処理の順序を判断するため、これは重要です。

3.3.13. layouttype4
3.3.13. LayoutType4
   enum layouttype4 {
           LAYOUT4_NFSV4_1_FILES   = 0x1,
           LAYOUT4_OSD2_OBJECTS    = 0x2,
           LAYOUT4_BLOCK_VOLUME    = 0x3

This data type indicates what type of layout is being used. The file server advertises the layout types it supports through the fs_layout_type file system attribute (Section 5.12.1). A client asks for layouts of a particular type in LAYOUTGET, and processes those layouts in its layout-type-specific logic.


The layouttype4 data type is 32 bits in length. The range represented by the layout type is split into three parts. Type 0x0 is reserved. Types within the range 0x00000001-0x7FFFFFFF are globally unique and are assigned according to the description in Section 22.5; they are maintained by IANA. Types within the range 0x80000000-0xFFFFFFFF are site specific and for private use only.


The LAYOUT4_NFSV4_1_FILES enumeration specifies that the NFSv4.1 file layout type, as defined in Section 13, is to be used. The LAYOUT4_OSD2_OBJECTS enumeration specifies that the object layout, as defined in [47], is to be used. Similarly, the LAYOUT4_BLOCK_VOLUME enumeration specifies that the block/volume layout, as defined in [48], is to be used.


3.3.14. deviceid4
3.3.14. DeviceID4

const NFS4_DEVICEID4_SIZE = 16;

const nfs4_deviceId4_size = 16;

typedef opaque deviceid4[NFS4_DEVICEID4_SIZE];

typedef opaque deviceId4 [NFS4_DeviceID4_SIZE];

Layout information includes device IDs that specify a storage device through a compact handle. Addressing and type information is obtained with the GETDEVICEINFO operation. Device IDs are not guaranteed to be valid across metadata server restarts. A device ID is unique per client ID and layout type. See Section 12.2.10 for more details.


3.3.15. device_addr4
3.3.15. device_addr4
   struct device_addr4 {
           layouttype4             da_layout_type;
           opaque                  da_addr_body<>;

The device address is used to set up a communication channel with the storage device. Different layout types will require different data types to define how they communicate with storage devices. The opaque da_addr_body field is interpreted based on the specified da_layout_type field.

機器アドレスは、記憶装置と通信チャネルを設定するために使用される。さまざまなレイアウト型には、データ型がストレージデバイスとの通信方法を定義する必要があります。opaque da_addr_bodyフィールドは、指定されたda_layout_typeフィールドに基づいて解釈されます。

This document defines the device address for the NFSv4.1 file layout (see Section 13.3), which identifies a storage device by network IP address and port number. This is sufficient for the clients to communicate with the NFSv4.1 storage devices, and may be sufficient for other layout types as well. Device types for object-based storage devices and block storage devices (e.g., Small Computer System Interface (SCSI) volume labels) are defined by their respective layout specifications.


3.3.16. layout_content4
3.3.16. Layout_Content4
   struct layout_content4 {
           layouttype4 loc_type;
           opaque      loc_body<>;

The loc_body field is interpreted based on the layout type (loc_type). This document defines the loc_body for the NFSv4.1 file layout type; see Section 13.3 for its definition.


3.3.17. layout4
3.3.17. レイアウト4
   struct layout4 {
           offset4                 lo_offset;
           length4                 lo_length;
           layoutiomode4           lo_iomode;
           layout_content4         lo_content;

The layout4 data type defines a layout for a file. The layout type specific data is opaque within lo_content. Since layouts are sub-dividable, the offset and length together with the file's filehandle, the client ID, iomode, and layout type identify the layout.


3.3.18. layoutupdate4
3.3.18. LayoutUpdate4
   struct layoutupdate4 {
           layouttype4             lou_type;
           opaque                  lou_body<>;

The layoutupdate4 data type is used by the client to return updated layout information to the metadata server via the LAYOUTCOMMIT (Section 18.42) operation. This data type provides a channel to pass layout type specific information (in field lou_body) back to the metadata server. For example, for the block/volume layout type, this could include the list of reserved blocks that were written. The contents of the opaque lou_body argument are determined by the layout type. The NFSv4.1 file-based layout does not use this data type; if lou_type is LAYOUT4_NFSV4_1_FILES, the lou_body field MUST have a zero length.


3.3.19. layouthint4
3.3.19. layoushint4.
   struct layouthint4 {
           layouttype4             loh_type;
           opaque                  loh_body<>;

The layouthint4 data type is used by the client to pass in a hint about the type of layout it would like created for a particular file. It is the data type specified by the layout_hint attribute described in Section 5.12.4. The metadata server may ignore the hint or may selectively ignore fields within the hint. This hint should be provided at create time as part of the initial attributes within OPEN. The loh_body field is specific to the type of layout (loh_type). The NFSv4.1 file-based layout uses the nfsv4_1_file_layouthint4 data type as defined in Section 13.3.

LayouseInt4データ型は、特定のファイルに対して作成したいレイアウトの種類についてヒントを渡すためにクライアントによって使用されます。それは、5.12.4項で説明されているlayout_hint属性によって指定されたデータ型です。メタデータサーバーはヒントを無視することも、ヒント内のフィールドを選択的に無視することができます。このヒントは、Open内の初期属性の一部としてCREATE TIMEで提供されるべきです。LOH_BODYフィールドはレイアウトのタイプ(LOH_TYPE)に固有のものです。NFSV4.1ファイルベースのレイアウトは、セクション13.3で定義されているようにNFSV4_1_FILE_LAYOUTHINT4データ型を使用します。

3.3.20. layoutiomode4
3.3.20. LayoutiOmode4
   enum layoutiomode4 {
           LAYOUTIOMODE4_READ      = 1,
           LAYOUTIOMODE4_RW        = 2,
           LAYOUTIOMODE4_ANY       = 3

The iomode specifies whether the client intends to just read or both read and write the data represented by the layout. While the LAYOUTIOMODE4_ANY iomode MUST NOT be used in the arguments to the LAYOUTGET operation, it MAY be used in the arguments to the LAYOUTRETURN and CB_LAYOUTRECALL operations. The LAYOUTIOMODE4_ANY iomode specifies that layouts pertaining to both LAYOUTIOMODE4_READ and LAYOUTIOMODE4_RW iomodes are being returned or recalled, respectively. The metadata server's use of the iomode may depend on the layout type being used. The storage devices MAY validate I/O accesses against the iomode and reject invalid accesses.

IOMODEは、クライアントがレイアウトによって表されるデータを読み書きするだけで読み書きすることを意図しているかどうかを指定します。LayoutIomode4_any iomodeをLayoutget操作の引数で使用してはいけませんが、LayoutReturnおよびCB_LayoutRecall操作の引数で使用できます。LAYOUTIOMODE4_ANY IOMODEは、それぞれlayoutioMode4_readおよびlayoutioMode4_rw iomodeの両方に関連するレイアウトが返されるかリコールされていることを指定します。メタデータサーバのIOMODEの使用は、使用されているレイアウト型によって異なります。ストレージデバイスは、IOMODEに対してI / Oアクセスを検証し、無効なアクセスを拒否することができます。

3.3.21. nfs_impl_id4
3.3.21. NFS_IMPL_ID4
   struct nfs_impl_id4 {
           utf8str_cis   nii_domain;
           utf8str_cs    nii_name;
           nfstime4      nii_date;

This data type is used to identify client and server implementation details. The nii_domain field is the DNS domain name with which the implementor is associated. The nii_name field is the product name of the implementation and is completely free form. It is RECOMMENDED that the nii_name be used to distinguish machine architecture, machine platforms, revisions, versions, and patch levels. The nii_date field is the timestamp of when the software instance was published or built.


3.3.22. threshold_item4
3.3.22. threshold_item4.
   struct threshold_item4 {
           layouttype4     thi_layout_type;
           bitmap4         thi_hintset;
           opaque          thi_hintlist<>;

This data type contains a list of hints specific to a layout type for helping the client determine when it should send I/O directly through the metadata server versus the storage devices. The data type consists of the layout type (thi_layout_type), a bitmap (thi_hintset) describing the set of hints supported by the server (they may differ based on the layout type), and a list of hints (thi_hintlist) whose content is determined by the hintset bitmap. See the mdsthreshold attribute for more details.

このデータ型は、クライアントがメタデータサーバとストレージデバイスを介して直接I / Oを送信する必要があるときにクライアントが判別するためのレイアウト型に固有のヒントのリストを含みます。データ型は、サーバーでサポートされているヒントのセットを記述するレイアウトタイプ(THI_LAYOUT_TYPE)で構成されています(レイアウトタイプに基づいて異なる場合があります)、コンテンツが決定されたヒント(THI_HINTLIST)のリスト(THI_HINTLIST)のリストからなります。ヒントセットビットマップ。詳細については、mdsthreshold属性を参照してください。

The thi_hintset field is a bitmap of the following values:


   | name                    | # | Data    | Description               |
   |                         |   | Type    |                           |
   | threshold4_read_size    | 0 | length4 | If a file's length is     |
   |                         |   |         | less than the value of    |
   |                         |   |         | threshold4_read_size,     |
   |                         |   |         | then it is RECOMMENDED    |
   |                         |   |         | that the client read      |
   |                         |   |         | from the file via the     |
   |                         |   |         | MDS and not a storage     |
   |                         |   |         | device.                   |
   | threshold4_write_size   | 1 | length4 | If a file's length is     |
   |                         |   |         | less than the value of    |
   |                         |   |         | threshold4_write_size,    |
   |                         |   |         | then it is RECOMMENDED    |
   |                         |   |         | that the client write     |
   |                         |   |         | to the file via the       |
   |                         |   |         | MDS and not a storage     |
   |                         |   |         | device.                   |
   | threshold4_read_iosize  | 2 | length4 | For read I/O sizes        |
   |                         |   |         | below this threshold,     |
   |                         |   |         | it is RECOMMENDED to      |
   |                         |   |         | read data through the     |
   |                         |   |         | MDS.                      |
   | threshold4_write_iosize | 3 | length4 | For write I/O sizes       |
   |                         |   |         | below this threshold,     |
   |                         |   |         | it is RECOMMENDED to      |
   |                         |   |         | write data through the    |
   |                         |   |         | MDS.                      |

Table 2


3.3.23. mdsthreshold4
3.3.23. mdsthreshold4.
   struct mdsthreshold4 {
           threshold_item4 mth_hints<>;

This data type holds an array of elements of data type threshold_item4, each of which is valid for a particular layout type. An array is necessary because a server can support multiple layout types for a single file.


4. Filehandles
4. ファイルハンドル

The filehandle in the NFS protocol is a per-server unique identifier for a file system object. The contents of the filehandle are opaque to the client. Therefore, the server is responsible for translating the filehandle to an internal representation of the file system object.


4.1. Obtaining the First Filehandle
4.1. 最初のファイルハンドルを入手する

The operations of the NFS protocol are defined in terms of one or more filehandles. Therefore, the client needs a filehandle to initiate communication with the server. With the NFSv3 protocol (RFC 1813 [38]), there exists an ancillary protocol to obtain this first filehandle. The MOUNT protocol, RPC program number 100005, provides the mechanism of translating a string-based file system pathname to a filehandle, which can then be used by the NFS protocols.

NFSプロトコルの動作は、1つ以上のファイルハンドルに関して定義されています。したがって、クライアントはサーバーとの通信を開始するためのファイルハンドルが必要です。NFSV3プロトコル(RFC 1813 [38])では、この最初のファイルハンドルを取得するための補助プロトコルがあります。マウントプロトコルRPCプログラム番号100005は、文字列ベースのファイルシステムパス名をファイルハンドルに変換するメカニズムを提供します。これはNFSプロトコルによって使用できます。

The MOUNT protocol has deficiencies in the area of security and use via firewalls. This is one reason that the use of the public filehandle was introduced in RFC 2054 [49] and RFC 2055 [50]. With the use of the public filehandle in combination with the LOOKUP operation in the NFSv3 protocol, it has been demonstrated that the MOUNT protocol is unnecessary for viable interaction between NFS client and server.

マウントプロトコルには、セキュリティの分野内の欠陥があり、ファイアウォールを介して使用します。これは、Public FileHandleの使用がRFC 2054 [49]とRFC 2055で導入された理由の1つです[50]。NFSV3プロトコルのルックアップ操作と組み合わせてパブリックファイルハンドルを使用すると、NFSクライアントとサーバ間の実行可能な対話にはマウントプロトコルが不要であることが実証されている。

Therefore, the NFSv4.1 protocol will not use an ancillary protocol for translation from string-based pathnames to a filehandle. Two special filehandles will be used as starting points for the NFS client.


4.1.1. Root Filehandle
4.1.1. ルートファイルハンドル

The first of the special filehandles is the ROOT filehandle. The ROOT filehandle is the "conceptual" root of the file system namespace at the NFS server. The client uses or starts with the ROOT filehandle by employing the PUTROOTFH operation. The PUTROOTFH operation instructs the server to set the "current" filehandle to the ROOT of the server's file tree. Once this PUTROOTFH operation is used, the client can then traverse the entirety of the server's file tree with the LOOKUP operation. A complete discussion of the server namespace is in Section 7.

特別なファイルハンドルの最初のファイルハンドルはルートファイルハンドルです。ルートファイルハンドルは、NFSサーバーのファイルシステム名前空間の「概念的な」ルートです。クライアントは、PUTROOTFH操作を使用してルートファイルハンドルで使用または開始します。PUTROOTFH操作は、サーバーのファイルツリーのルートに "current"ファイルハンドルを設定するようにサーバーに指示します。このPUTROOTFH操作が使用されると、クライアントはルックアップ操作でサーバーのファイルツリーの全体を通過できます。サーバーネームスペースの完全な説明はセクション7にあります。

4.1.2. Public Filehandle
4.1.2. パブリックファイルハンドル

The second special filehandle is the PUBLIC filehandle. Unlike the ROOT filehandle, the PUBLIC filehandle may be bound or represent an arbitrary file system object at the server. The server is responsible for this binding. It may be that the PUBLIC filehandle and the ROOT filehandle refer to the same file system object. However, it is up to the administrative software at the server and the policies of the server administrator to define the binding of the PUBLIC filehandle and server file system object. The client may not make any assumptions about this binding. The client uses the PUBLIC filehandle via the PUTPUBFH operation.


4.2. Filehandle Types
4.2. ファイルハンドルの種類

In the NFSv3 protocol, there was one type of filehandle with a single set of semantics. This type of filehandle is termed "persistent" in NFSv4.1. The semantics of a persistent filehandle remain the same as before. A new type of filehandle introduced in NFSv4.1 is the "volatile" filehandle, which attempts to accommodate certain server environments.

NFSV3プロトコルでは、単一セットのセマンティクスを持つファイルハンドルのタイプのファイルハンドルがありました。このタイプのファイルハンドルは、NFSv4.1では "persistent"と呼ばれます。永続ファイルハンドルのセマンティクスは以前と同じままです。NFSV4.1で導入された新しいタイプのファイルハンドルは、特定のサーバー環境に対応しようとしている「揮発性」ファイルハンドルです。

The volatile filehandle type was introduced to address server functionality or implementation issues that make correct implementation of a persistent filehandle infeasible. Some server environments do not provide a file-system-level invariant that can be used to construct a persistent filehandle. The underlying server file system may not provide the invariant or the server's file system programming interfaces may not provide access to the needed invariant. Volatile filehandles may ease the implementation of server functionality such as hierarchical storage management or file system reorganization or migration. However, the volatile filehandle increases the implementation burden for the client.


Since the client will need to handle persistent and volatile filehandles differently, a file attribute is defined that may be used by the client to determine the filehandle types being returned by the server.


4.2.1. General Properties of a Filehandle
4.2.1. ファイルハンドルの一般的なプロパティ

The filehandle contains all the information the server needs to distinguish an individual file. To the client, the filehandle is opaque. The client stores filehandles for use in a later request and can compare two filehandles from the same server for equality by doing a byte-by-byte comparison. However, the client MUST NOT otherwise interpret the contents of filehandles. If two filehandles from the same server are equal, they MUST refer to the same file. Servers SHOULD try to maintain a one-to-one correspondence between filehandles and files, but this is not required. Clients MUST use filehandle comparisons only to improve performance, not for correct behavior. All clients need to be prepared for situations in which it cannot be determined whether two filehandles denote the same object and in such cases, avoid making invalid assumptions that might cause incorrect behavior. Further discussion of filehandle and attribute comparison in the context of data caching is presented in Section 10.3.4.

FileHandleには、サーバーが個々のファイルを区別する必要があるすべての情報が含まれています。クライアントに、ファイルハンドルは不透明です。クライアントは後の要求で使用するためのファイルハンドルを格納し、バイトごとの比較を行うことで同じサーバーから2つのファイルハンドルを比較できます。ただし、クライアントは特にファイルハンドルの内容を解釈してはいけません。同じサーバーから2つのファイルハンドルが等しい場合は、同じファイルを参照する必要があります。サーバーはファイルハンドルとファイル間の一対一の対応を維持しようとするはずですが、これは必須ではありません。クライアントは、正しい動作ではなく、パフォーマンスを向上させるためにのみFileHandle比較を使用する必要があります。 2つのファイルハンドルが同じオブジェクトを示すかどうか、そのような場合には誤った動作を引き起こす可能性があるという無効な仮定を避けることができない場合に、すべてのクライアントを準備する必要があります。データキャッシングのコンテキストにおけるFileHandleと属性比較の詳細については、10.3.4項に示されています。

As an example, in the case that two different pathnames when traversed at the server terminate at the same file system object, the server SHOULD return the same filehandle for each path. This can occur if a hard link (see [Section 3.191 of Chapter 3 of Base Definitions of The Open Group Base Specifications Issue 6 IEEE Std 1003.1, 2004 Edition, HTML Version"">6]) is used to create two file names that refer to the same underlying file object and associated data. For example, if paths /a/b/c and /a/d/c refer to the same file, the server SHOULD return the same filehandle for both pathnames' traversals.

例として、サーバーが同じファイルシステムオブジェクトで終了したときに2つの異なるパス名がある場合、サーバーは各パスに対して同じファイルハンドルを返す必要があります。これは、ハードリンクの場合に発生する可能性があります([オープングループベース仕様の開始6 IEEE STD 1003.1,2004エディション、HTMLバージョン ""> 6]の基本定義の第3章のセクション3.191)は、参照する2つのファイル名を作成するために使用されます。同じ基礎となるファイルオブジェクトと関連データに。たとえば、PATHS / A / B / Cおよび/ A / D / Cが同じファイルを参照している場合、サーバーは両方のパス名のトラバースに同じファイルハンドルを返す必要があります。

4.2.2. Persistent Filehandle
4.2.2. 永続的なファイルハンドル

A persistent filehandle is defined as having a fixed value for the lifetime of the file system object to which it refers. Once the server creates the filehandle for a file system object, the server MUST accept the same filehandle for the object for the lifetime of the object. If the server restarts, the NFS server MUST honor the same filehandle value as it did in the server's previous instantiation. Similarly, if the file system is migrated, the new NFS server MUST honor the same filehandle as the old NFS server.


The persistent filehandle will be become stale or invalid when the file system object is removed. When the server is presented with a persistent filehandle that refers to a deleted object, it MUST return an error of NFS4ERR_STALE. A filehandle may become stale when the file system containing the object is no longer available. The file system may become unavailable if it exists on removable media and the media is no longer available at the server or the file system in whole has been destroyed or the file system has simply been removed from the server's namespace (i.e., unmounted in a UNIX environment).


4.2.3. Volatile Filehandle
4.2.3. 揮発性のファイルハンドル

A volatile filehandle does not share the same longevity characteristics of a persistent filehandle. The server may determine that a volatile filehandle is no longer valid at many different points in time. If the server can definitively determine that a volatile filehandle refers to an object that has been removed, the server should return NFS4ERR_STALE to the client (as is the case for persistent filehandles). In all other cases where the server determines that a volatile filehandle can no longer be used, it should return an error of NFS4ERR_FHEXPIRED.


The REQUIRED attribute "fh_expire_type" is used by the client to determine what type of filehandle the server is providing for a particular file system. This attribute is a bitmask with the following values:

必要な属性 "fh_expire_type"は、サーバーが特定のファイルシステムを提供しているファイルハンドルの種類を決定するためにクライアントによって使用されます。この属性は、次の値を持つビットマスクです。

FH4_PERSISTENT The value of FH4_PERSISTENT is used to indicate a persistent filehandle, which is valid until the object is removed from the file system. The server will not return NFS4ERR_FHEXPIRED for this filehandle. FH4_PERSISTENT is defined as a value in which none of the bits specified below are set.

FH4_PERSINTENT FH4_PerSistentの値は、オブジェクトがファイルシステムから削除されるまで有効な永続的なファイルハンドルを示すために使用されます。このファイルハンドルのNFS4ERR_FHEXPIEDを返しません。FH4_Persistentは、以下に指定されたビットが設定されていない値として定義されています。

FH4_VOLATILE_ANY The filehandle may expire at any time, except as specifically excluded (i.e., FH4_NO_EXPIRE_WITH_OPEN).

FH4_VOLATILE_ANY FILEHANDLEは、特に除外された場合(すなわち、FH4_NO_EXPIRE_WITH_OPEN)を除いて、いつでも期限切れになる可能性があります。

FH4_NOEXPIRE_WITH_OPEN May only be set when FH4_VOLATILE_ANY is set. If this bit is set, then the meaning of FH4_VOLATILE_ANY is qualified to exclude any expiration of the filehandle when it is open.


FH4_VOL_MIGRATION The filehandle will expire as a result of a file system transition (migration or replication), in those cases in which the continuity of filehandle use is not specified by handle class information within the fs_locations_info attribute. When this bit is set, clients without access to fs_locations_info information should assume that filehandles will expire on file system transitions.

FH4_VOL_MIGRATION FILE Handleの継続性がFS_LOCATIONS_INFO属性内のハンドルクラス情報で指定されていない場合、ファイルハンドルはファイルシステムの遷移(移行または複製)の結果として期限切れになります。このビットが設定されている場合、FS_LOCATIONS_INFO情報へのアクセスなしのクライアントは、ファイルハンドルがファイルシステムの遷移時に期限切れになると想定する必要があります。

FH4_VOL_RENAME The filehandle will expire during rename. This includes a rename by the requesting client or a rename by any other client. If FH4_VOL_ANY is set, FH4_VOL_RENAME is redundant.


Servers that provide volatile filehandles that can expire while open require special care as regards handling of RENAMEs and REMOVEs. This situation can arise if FH4_VOL_MIGRATION or FH4_VOL_RENAME is set, if FH4_VOLATILE_ANY is set and FH4_NOEXPIRE_WITH_OPEN is not set, or if a non-read-only file system has a transition target in a different handle class. In these cases, the server should deny a RENAME or REMOVE that would affect an OPEN file of any of the components leading to the OPEN file. In addition, the server should deny all RENAME or REMOVE requests during the grace period, in order to make sure that reclaims of files where filehandles may have expired do not do a reclaim for the wrong file.


Volatile filehandles are especially suitable for implementation of the pseudo file systems used to bridge exports. See Section 7.5 for a discussion of this.


4.3. One Method of Constructing a Volatile Filehandle
4.3. 揮発性ファイルハンドルを構築する1つの方法

A volatile filehandle, while opaque to the client, could contain:


[volatile bit = 1 | server boot time | slot | generation number]

[揮発性ビット= 1

* slot is an index in the server volatile filehandle table

* スロットはサーバー揮発性ファイルハンドルテーブルのインデックスです。

* generation number is the generation number for the table entry/ slot

* 世代番号はテーブルエントリ/スロットの世代番号です

When the client presents a volatile filehandle, the server makes the following checks, which assume that the check for the volatile bit has passed. If the server boot time is less than the current server boot time, return NFS4ERR_FHEXPIRED. If slot is out of range, return NFS4ERR_BADHANDLE. If the generation number does not match, return NFS4ERR_FHEXPIRED.


When the server restarts, the table is gone (it is volatile).


If the volatile bit is 0, then it is a persistent filehandle with a different structure following it.


4.4. Client Recovery from Filehandle Expiration
4.4. FileHandleの有効期限からのクライアントの回復

If possible, the client SHOULD recover from the receipt of an NFS4ERR_FHEXPIRED error. The client must take on additional responsibility so that it may prepare itself to recover from the expiration of a volatile filehandle. If the server returns persistent filehandles, the client does not need these additional steps.


For volatile filehandles, most commonly the client will need to store the component names leading up to and including the file system object in question. With these names, the client should be able to recover by finding a filehandle in the namespace that is still available or by starting at the root of the server's file system namespace.


If the expired filehandle refers to an object that has been removed from the file system, obviously the client will not be able to recover from the expired filehandle.


It is also possible that the expired filehandle refers to a file that has been renamed. If the file was renamed by another client, again it is possible that the original client will not be able to recover. However, in the case that the client itself is renaming the file and the file is open, it is possible that the client may be able to recover. The client can determine the new pathname based on the processing of the rename request. The client can then regenerate the new filehandle based on the new pathname. The client could also use the COMPOUND procedure to construct a series of operations like:



ルックアップB GETFHを変更します

Note that the COMPOUND procedure does not provide atomicity. This example only reduces the overhead of recovering from an expired filehandle.


5. File Attributes
5. ファイル属性

To meet the requirements of extensibility and increased interoperability with non-UNIX platforms, attributes need to be handled in a flexible manner. The NFSv3 fattr3 structure contains a fixed list of attributes that not all clients and servers are able to support or care about. The fattr3 structure cannot be extended as new needs arise and it provides no way to indicate non-support. With the NFSv4.1 protocol, the client is able to query what attributes the server supports and construct requests with only those supported attributes (or a subset thereof).

非UNIXプラットフォームとの伸張性の要件を満たすために、属性は柔軟な方法で処理される必要があります。NFSV3 FATTR3構造には、すべてのクライアントとサーバーがサポートまたはケアが可能ではない属性の固定リストが含まれています。FATTR3構造は新しいニーズが発生するにつれて拡張することはできず、非サポートを示す方法はありません。NFSV4.1プロトコルを使用すると、クライアントはサーバーがサポートされている属性(またはそのサブセット)のみで要求をサポートおよび構築する属性を照会することができます。

To this end, attributes are divided into three groups: REQUIRED, RECOMMENDED, and named. Both REQUIRED and RECOMMENDED attributes are supported in the NFSv4.1 protocol by a specific and well-defined encoding and are identified by number. They are requested by setting a bit in the bit vector sent in the GETATTR request; the server response includes a bit vector to list what attributes were returned in the response. New REQUIRED or RECOMMENDED attributes may be added to the NFSv4 protocol as part of a new minor version by publishing a Standards Track RFC that allocates a new attribute number value and defines the encoding for the attribute. See Section 2.7 for further discussion.


Named attributes are accessed by the new OPENATTR operation, which accesses a hidden directory of attributes associated with a file system object. OPENATTR takes a filehandle for the object and returns the filehandle for the attribute hierarchy. The filehandle for the named attributes is a directory object accessible by LOOKUP or READDIR and contains files whose names represent the named attributes and whose data bytes are the value of the attribute. For example:


        | LOOKUP   | "foo"     | ; look up file                  |
        | GETATTR  | attrbits  |                                 |
        | OPENATTR |           | ; access foo's named attributes |
        | LOOKUP   | "x11icon" | ; look up specific attribute    |
        | READ     | 0,4096    | ; read stream of bytes          |

Table 3


Named attributes are intended for data needed by applications rather than by an NFS client implementation. NFS implementors are strongly encouraged to define their new attributes as RECOMMENDED attributes by bringing them to the IETF Standards Track process.


The set of attributes that are classified as REQUIRED is deliberately small since servers need to do whatever it takes to support them. A server should support as many of the RECOMMENDED attributes as possible but, by their definition, the server is not required to support all of them. Attributes are deemed REQUIRED if the data is both needed by a large number of clients and is not otherwise reasonably computable by the client when support is not provided on the server.


Note that the hidden directory returned by OPENATTR is a convenience for protocol processing. The client should not make any assumptions about the server's implementation of named attributes and whether or not the underlying file system at the server has a named attribute directory. Therefore, operations such as SETATTR and GETATTR on the named attribute directory are undefined.


5.1. REQUIRED Attributes
5.1. 必須属性

These MUST be supported by every NFSv4.1 client and server in order to ensure a minimum level of interoperability. The server MUST store and return these attributes, and the client MUST be able to function with an attribute set limited to these attributes. With just the REQUIRED attributes some client functionality may be impaired or limited in some ways. A client may ask for any of these attributes to be returned by setting a bit in the GETATTR request, and the server MUST return their value.


5.2. RECOMMENDED Attributes
5.2. 推奨される属性

These attributes are understood well enough to warrant support in the NFSv4.1 protocol. However, they may not be supported on all clients and servers. A client may ask for any of these attributes to be returned by setting a bit in the GETATTR request but must handle the case where the server does not return them. A client MAY ask for the set of attributes the server supports and SHOULD NOT request attributes the server does not support. A server should be tolerant of requests for unsupported attributes and simply not return them rather than considering the request an error. It is expected that servers will support all attributes they comfortably can and only fail to support attributes that are difficult to support in their operating environments. A server should provide attributes whenever they don't have to "tell lies" to the client. For example, a file modification time should be either an accurate time or should not be supported by the server. At times this will be difficult for clients, but a client is better positioned to decide whether and how to fabricate or construct an attribute or whether to do without the attribute.


5.3. Named Attributes
5.3. 名前付き属性

These attributes are not supported by direct encoding in the NFSv4 protocol but are accessed by string names rather than numbers and correspond to an uninterpreted stream of bytes that are stored with the file system object. The namespace for these attributes may be accessed by using the OPENATTR operation. The OPENATTR operation returns a filehandle for a virtual "named attribute directory", and further perusal and modification of the namespace may be done using operations that work on more typical directories. In particular, READDIR may be used to get a list of such named attributes, and LOOKUP and OPEN may select a particular attribute. Creation of a new named attribute may be the result of an OPEN specifying file creation.


Once an OPEN is done, named attributes may be examined and changed by normal READ and WRITE operations using the filehandles and stateids returned by OPEN.


Named attributes and the named attribute directory may have their own (non-named) attributes. Each of these objects MUST have all of the REQUIRED attributes and may have additional RECOMMENDED attributes. However, the set of attributes for named attributes and the named attribute directory need not be, and typically will not be, as large as that for other objects in that file system.


Named attributes and the named attribute directory might be the target of delegations (in the case of the named attribute directory, these will be directory delegations). However, since granting of delegations is at the server's discretion, a server need not support delegations on named attributes or the named attribute directory.


It is RECOMMENDED that servers support arbitrary named attributes. A client should not depend on the ability to store any named attributes in the server's file system. If a server does support named attributes, a client that is also able to handle them should be able to copy a file's data and metadata with complete transparency from one location to another; this would imply that names allowed for regular directory entries are valid for named attribute names as well.


In NFSv4.1, the structure of named attribute directories is restricted in a number of ways, in order to prevent the development of non-interoperable implementations in which some servers support a fully general hierarchical directory structure for named attributes while others support a limited but adequate structure for named attributes. In such an environment, clients or applications might come to depend on non-portable extensions. The restrictions are:


* CREATE is not allowed in a named attribute directory. Thus, such objects as symbolic links and special files are not allowed to be named attributes. Further, directories may not be created in a named attribute directory, so no hierarchical structure of named attributes for a single object is allowed.

* 名前付き属性ディレクトリには作成は許可されていません。したがって、シンボリックリンクと特殊ファイルとのようなオブジェクトは、属性の名前を付けられていません。さらに、ディレクトリは名前付き属性ディレクトリに作成されないため、単一のオブジェクトの名前付き属性の階層構造は許可されません。

* If OPENATTR is done on a named attribute directory or on a named attribute, the server MUST return NFS4ERR_WRONG_TYPE.

* openattrが名前付き属性ディレクトリまたは名前付き属性で行われている場合、サーバーはNFS4ERR_WRONG_TYPEを返す必要があります。

* Doing a RENAME of a named attribute to a different named attribute directory or to an ordinary (i.e., non-named-attribute) directory is not allowed.

* 名前付き属性の名前付き属性の名前付き属性ディレクトリまたは通常(すなわち、non-non-属性)ディレクトリに変更することはできません。

* Creating hard links between named attribute directories or between named attribute directories and ordinary directories is not allowed.

* 名前付き属性ディレクトリ間または名前付き属性ディレクトリと通常のディレクトリ間のハードリンクを作成することは許可されていません。

Names of attributes will not be controlled by this document or other IETF Standards Track documents. See Section 22.2 for further discussion.


5.4. Classification of Attributes
5.4. 属性の分類

Each of the REQUIRED and RECOMMENDED attributes can be classified in one of three categories: per server (i.e., the value of the attribute will be the same for all file objects that share the same server owner; see Section 2.5 for a definition of server owner), per file system (i.e., the value of the attribute will be the same for some or all file objects that share the same fsid attribute (Section and server owner), or per file system object. Note that it is possible that some per file system attributes may vary within the file system, depending on the value of the "homogeneous" (Section attribute. Note that the attributes time_access_set and time_modify_set are not listed in this section because they are write-only attributes corresponding to time_access and time_modify, and are used in a special instance of SETATTR.


* The per-server attribute is:

* サーバーごとの属性は次のとおりです。



* The per-file system attributes are:

* ファイルごとのシステム属性は次のとおりです。

supported_attrs, suppattr_exclcreat, fh_expire_type, link_support, symlink_support, unique_handles, aclsupport, cansettime, case_insensitive, case_preserving, chown_restricted, files_avail, files_free, files_total, fs_locations, homogeneous, maxfilesize, maxname, maxread, maxwrite, no_trunc, space_avail, space_free, space_total, time_delta, change_policy, fs_status, fs_layout_type, fs_locations_info, fs_charset_cap


* The per-file system object attributes are:

* ファイルごとのシステムオブジェクト属性は次のとおりです。

type, change, size, named_attr, fsid, rdattr_error, filehandle, acl, archive, fileid, hidden, maxlink, mimetype, mode, numlinks, owner, owner_group, rawdev, space_used, system, time_access, time_backup, time_create, time_metadata, time_modify, mounted_on_fileid, dir_notif_delay, dirent_notif_delay, dacl, sacl, layout_type, layout_hint, layout_blksize, layout_alignment, mdsthreshold, retention_get, retention_set, retentevt_get, retentevt_set, retention_hold, mode_set_masked


For quota_avail_hard, quota_avail_soft, and quota_used, see their definitions below for the appropriate classification.


5.5. Set-Only and Get-Only Attributes
5.5. セット専用およびGET専用の属性

Some REQUIRED and RECOMMENDED attributes are set-only; i.e., they can be set via SETATTR but not retrieved via GETATTR. Similarly, some REQUIRED and RECOMMENDED attributes are get-only; i.e., they can be retrieved via GETATTR but not set via SETATTR. If a client attempts to set a get-only attribute or get a set-only attributes, the server MUST return NFS4ERR_INVAL.


5.6. REQUIRED Attributes - List and Definition References
5.6. 必須属性 - リストと定義参照

The list of REQUIRED attributes appears in Table 4. The meaning of the columns of the table are:


Name: The name of the attribute.


Id: The number assigned to the attribute. In the event of conflicts between the assigned number and [10], the latter is likely authoritative, but should be resolved with Errata to this document and/or [10]. See [51] for the Errata process.


Data Type: The XDR data type of the attribute.


Acc: Access allowed to the attribute. R means read-only (GETATTR may retrieve, SETATTR may not set). W means write-only (SETATTR may set, GETATTR may not retrieve). R W means read/write (GETATTR may retrieve, SETATTR may set).

ACC:属性に許可されています。Rは読み取り専用を意味します(GetAttrが取得し、setAttrは設定されていない場合があります)。w書き込み専用(SetAttrが設定されている、getAttrが取得できない場合があります)。R wは読み取り/書き込みを意味します(GetAttrが取得して、SetAttrは設定されています)。

Defined in: The section of this specification that describes the attribute.


     | Name               | Id | Data Type  | Acc | Defined in:      |
     | supported_attrs    | 0  | bitmap4    | R   | Section  |
     | type               | 1  | nfs_ftype4 | R   | Section  |
     | fh_expire_type     | 2  | uint32_t   | R   | Section  |
     | change             | 3  | uint64_t   | R   | Section  |
     | size               | 4  | uint64_t   | R W | Section  |
     | link_support       | 5  | bool       | R   | Section  |
     | symlink_support    | 6  | bool       | R   | Section  |
     | named_attr         | 7  | bool       | R   | Section  |
     | fsid               | 8  | fsid4      | R   | Section  |
     | unique_handles     | 9  | bool       | R   | Section |
     | lease_time         | 10 | nfs_lease4 | R   | Section |
     | rdattr_error       | 11 | enum       | R   | Section |
     | filehandle         | 19 | nfs_fh4    | R   | Section |
     | suppattr_exclcreat | 75 | bitmap4    | R   | Section |

Table 4


5.7. RECOMMENDED Attributes - List and Definition References
5.7. 推奨される属性 - リストと定義の参照

The RECOMMENDED attributes are defined in Table 5. The meanings of the column headers are the same as Table 4; see Section 5.6 for the meanings.


   | Name               | Id | Data Type          | Acc | Defined in: |
   | acl                | 12 | nfsace4<>          | R W | Section     |
   |                    |    |                    |     | 6.2.1       |
   | aclsupport         | 13 | uint32_t           | R   | Section     |
   |                    |    |                    |     |     |
   | archive            | 14 | bool               | R W | Section     |
   |                    |    |                    |     |     |
   | cansettime         | 15 | bool               | R   | Section     |
   |                    |    |                    |     |     |
   | case_insensitive   | 16 | bool               | R   | Section     |
   |                    |    |                    |     |     |
   | case_preserving    | 17 | bool               | R   | Section     |
   |                    |    |                    |     |     |
   | change_policy      | 60 | chg_policy4        | R   | Section     |
   |                    |    |                    |     |     |
   | chown_restricted   | 18 | bool               | R   | Section     |
   |                    |    |                    |     |     |
   | dacl               | 58 | nfsacl41           | R W | Section     |
   |                    |    |                    |     | 6.2.2       |
   | dir_notif_delay    | 56 | nfstime4           | R   | Section     |
   |                    |    |                    |     | 5.11.1      |
   | dirent_notif_delay | 57 | nfstime4           | R   | Section     |
   |                    |    |                    |     | 5.11.2      |
   | fileid             | 20 | uint64_t           | R   | Section     |
   |                    |    |                    |     |     |
   | files_avail        | 21 | uint64_t           | R   | Section     |
   |                    |    |                    |     |     |
   | files_free         | 22 | uint64_t           | R   | Section     |
   |                    |    |                    |     |     |
   | files_total        | 23 | uint64_t           | R   | Section     |
   |                    |    |                    |     |    |
   | fs_charset_cap     | 76 | uint32_t           | R   | Section     |
   |                    |    |                    |     |    |
   | fs_layout_type     | 62 | layouttype4<>      | R   | Section     |
   |                    |    |                    |     | 5.12.1      |
   | fs_locations       | 24 | fs_locations       | R   | Section     |
   |                    |    |                    |     |    |
   | fs_locations_info  | 67 | fs_locations_info4 | R   | Section     |
   |                    |    |                    |     |    |
   | fs_status          | 61 | fs4_status         | R   | Section     |
   |                    |    |                    |     |    |
   | hidden             | 25 | bool               | R W | Section     |
   |                    |    |                    |     |    |
   | homogeneous        | 26 | bool               | R   | Section     |
   |                    |    |                    |     |    |
   | layout_alignment   | 66 | uint32_t           | R   | Section     |
   |                    |    |                    |     | 5.12.2      |
   | layout_blksize     | 65 | uint32_t           | R   | Section     |
   |                    |    |                    |     | 5.12.3      |
   | layout_hint        | 63 | layouthint4        |   W | Section     |
   |                    |    |                    |     | 5.12.4      |
   | layout_type        | 64 | layouttype4<>      | R   | Section     |
   |                    |    |                    |     | 5.12.5      |
   | maxfilesize        | 27 | uint64_t           | R   | Section     |
   |                    |    |                    |     |    |
   | maxlink            | 28 | uint32_t           | R   | Section     |
   |                    |    |                    |     |    |
   | maxname            | 29 | uint32_t           | R   | Section     |
   |                    |    |                    |     |    |
   | maxread            | 30 | uint64_t           | R   | Section     |
   |                    |    |                    |     |    |
   | maxwrite           | 31 | uint64_t           | R   | Section     |
   |                    |    |                    |     |    |
   | mdsthreshold       | 68 | mdsthreshold4      | R   | Section     |
   |                    |    |                    |     | 5.12.6      |
   | mimetype           | 32 | utf8str_cs         | R W | Section     |
   |                    |    |                    |     |    |
   | mode               | 33 | mode4              | R W | Section     |
   |                    |    |                    |     | 6.2.4       |
   | mode_set_masked    | 74 | mode_masked4       |   W | Section     |
   |                    |    |                    |     | 6.2.5       |
   | mounted_on_fileid  | 55 | uint64_t           | R   | Section     |
   |                    |    |                    |     |    |
   | no_trunc           | 34 | bool               | R   | Section     |
   |                    |    |                    |     |    |
   | numlinks           | 35 | uint32_t           | R   | Section     |
   |                    |    |                    |     |    |
   | owner              | 36 | utf8str_mixed      | R W | Section     |
   |                    |    |                    |     |    |
   | owner_group        | 37 | utf8str_mixed      | R W | Section     |
   |                    |    |                    |     |    |
   | quota_avail_hard   | 38 | uint64_t           | R   | Section     |
   |                    |    |                    |     |    |
   | quota_avail_soft   | 39 | uint64_t           | R   | Section     |
   |                    |    |                    |     |    |
   | quota_used         | 40 | uint64_t           | R   | Section     |
   |                    |    |                    |     |    |
   | rawdev             | 41 | specdata4          | R   | Section     |
   |                    |    |                    |     |    |
   | retentevt_get      | 71 | retention_get4     | R   | Section     |
   |                    |    |                    |     | 5.13.3      |
   | retentevt_set      | 72 | retention_set4     |   W | Section     |
   |                    |    |                    |     | 5.13.4      |
   | retention_get      | 69 | retention_get4     | R   | Section     |
   |                    |    |                    |     | 5.13.1      |
   | retention_hold     | 73 | uint64_t           | R W | Section     |
   |                    |    |                    |     | 5.13.5      |
   | retention_set      | 70 | retention_set4     |   W | Section     |
   |                    |    |                    |     | 5.13.2      |
   | sacl               | 59 | nfsacl41           | R W | Section     |
   |                    |    |                    |     | 6.2.3       |
   | space_avail        | 42 | uint64_t           | R   | Section     |
   |                    |    |                    |     |    |
   | space_free         | 43 | uint64_t           | R   | Section     |
   |                    |    |                    |     |    |
   | space_total        | 44 | uint64_t           | R   | Section     |
   |                    |    |                    |     |    |
   | space_used         | 45 | uint64_t           | R   | Section     |
   |                    |    |                    |     |    |
   | system             | 46 | bool               | R W | Section     |
   |                    |    |                    |     |    |
   | time_access        | 47 | nfstime4           | R   | Section     |
   |                    |    |                    |     |    |
   | time_access_set    | 48 | settime4           |   W | Section     |
   |                    |    |                    |     |    |
   | time_backup        | 49 | nfstime4           | R W | Section     |
   |                    |    |                    |     |    |
   | time_create        | 50 | nfstime4           | R W | Section     |
   |                    |    |                    |     |    |
   | time_delta         | 51 | nfstime4           | R   | Section     |
   |                    |    |                    |     |    |
   | time_metadata      | 52 | nfstime4           | R   | Section     |
   |                    |    |                    |     |    |
   | time_modify        | 53 | nfstime4           | R   | Section     |
   |                    |    |                    |     |    |
   | time_modify_set    | 54 | settime4           |   W | Section     |
   |                    |    |                    |     |    |

Table 5


5.8. Attribute Definitions
5.8. 属性定義
5.8.1. Definitions of REQUIRED Attributes
5.8.1. 必要な属性の定義 Attribute 0: supported_attrs 属性0:supported_attrs.

The bit vector that would retrieve all REQUIRED and RECOMMENDED attributes that are supported for this object. The scope of this attribute applies to all objects with a matching fsid.

このオブジェクトでサポートされているすべての必須属性と推奨される属性を取得するビットベクトル。この属性の範囲は、一致するFSIDを持つすべてのオブジェクトに適用されます。 Attribute 1: type 属性1:タイプ

Designates the type of an object in terms of one of a number of special constants:


* NF4REG designates a regular file.

* NF4REGは通常のファイルを指定します。

* NF4DIR designates a directory.

* NF4DIRはディレクトリを指定します。

* NF4BLK designates a block device special file.

* NF4BLKはブロックデバイス特殊ファイルを指定します。

* NF4CHR designates a character device special file.

* NF4CHRは文字装置特殊ファイルを指定します。

* NF4LNK designates a symbolic link.

* NF4LNKはシンボリックリンクを指定します。

* NF4SOCK designates a named socket special file.

* NF4SOCK名前付きソケット特殊ファイルを指定します。

* NF4FIFO designates a fifo special file.

* NF4FIFOはFIFO特殊ファイルを指定します。

* NF4ATTRDIR designates a named attribute directory.

* NF4AttrDir名前付き属性ディレクトリを指定します。

* NF4NAMEDATTR designates a named attribute.

* NF4NamedAttrは名前付き属性を指定します。

Within the explanatory text and operation descriptions, the following phrases will be used with the meanings given below:


* The phrase "is a directory" means that the object's type attribute is NF4DIR or NF4ATTRDIR.

* "directory"というフレーズは、オブジェクトのtype属性がNF4DIRまたはNF4ATTRDIRであることを意味します。

* The phrase "is a special file" means that the object's type attribute is NF4BLK, NF4CHR, NF4SOCK, or NF4FIFO.

* 「は特別なファイル」というフレーズは、オブジェクトのtype属性がNF4BLK、NF4CHR、NF4SOCK、またはNF4FIFOであることを意味します。

* The phrases "is an ordinary file" and "is a regular file" mean that the object's type attribute is NF4REG or NF4NAMEDATTR.

* 「通常のファイル」と「通常のファイル」は、オブジェクトのtype属性がNF4REGまたはNF4NADEDATTRであることを意味します。 Attribute 2: fh_expire_type 属性2:FH_EXPIRE_TYPE

Server uses this to specify filehandle expiration behavior to the client. See Section 4 for additional description.

サーバーはこれを使用して、クライアントにFileHandleの有効期限の動作を指定します。追加の説明についてはセクション4を参照してください。 Attribute 3: change 属性3:変更

A value created by the server that the client can use to determine if file data, directory contents, or attributes of the object have been modified. The server may return the object's time_metadata attribute for this attribute's value, but only if the file system object cannot be updated more frequently than the resolution of time_metadata.

オブジェクトのファイルデータ、ディレクトリ内容、またはオブジェクトの属性が変更されたかどうかを判断するためにクライアントが使用できるサーバーによって作成された値。サーバーは、この属性の値のオブジェクトのtime_metadata属性を返すことができますが、ファイルシステムオブジェクトをtime_metadataの解像度よりも頻繁に更新できない場合に限ります。 Attribute 4: size 属性4:サイズ

The size of the object in bytes.

オブジェクトのサイズがバイト単位で。 Attribute 5: link_support 属性5:link_support.

TRUE, if the object's file system supports hard links.

オブジェクトのファイルシステムがハードリンクをサポートしている場合はtrueです。 Attribute 6: symlink_support 属性6:symlink_support.

TRUE, if the object's file system supports symbolic links.

オブジェクトのファイルシステムがシンボリックリンクをサポートしている場合はtrueです。 Attribute 7: named_attr 属性7:named_attr.

TRUE, if this object has named attributes. In other words, object has a non-empty named attribute directory.

このオブジェクトに名前が付けられた場合はtrueです。言い換えれば、オブジェクトは空でない名前付き属性ディレクトリを持ちます。 Attribute 8: fsid 属性8:FSID

Unique file system identifier for the file system holding this object. The fsid attribute has major and minor components, each of which are of data type uint64_t.

このオブジェクトを保持しているファイルシステムの固有ファイルシステム識別子。fsid属性にはメジャーコンポーネントとマイナーコンポーネントがあり、その各々はデータ型uint64_tです。 Attribute 9: unique_handles 属性9:Unique_Handles

TRUE, if two distinct filehandles are guaranteed to refer to two different file system objects.

2つの異なるファイルハンドルが2つの異なるファイルシステムオブジェクトを参照することが保証されている場合はtrue。 Attribute 10: lease_time 属性10:lease_time

Duration of the lease at server in seconds.

サーバーのリースの期間秒単位で。 Attribute 11: rdattr_error 属性11:RDATTR_ERROR

Error returned from an attempt to retrieve attributes during a READDIR operation.

READDIR操作中に属性を取得しようとしたときにエラーが返されました。 Attribute 19: filehandle 属性19:FileHandle.

The filehandle of this object (primarily for READDIR requests).

このオブジェクトのファイルハンドル(主にREADDIR要求の場合)。 Attribute 75: suppattr_exclcreat 属性75:suppattr_exclaceat

The bit vector that would set all REQUIRED and RECOMMENDED attributes that are supported by the EXCLUSIVE4_1 method of file creation via the OPEN operation. The scope of this attribute applies to all objects with a matching fsid.


5.8.2. Definitions of Uncategorized RECOMMENDED Attributes
5.8.2. 未分類推奨属性の定義

The definitions of most of the RECOMMENDED attributes follow. Collections that share a common category are defined in other sections.

推奨される属性の大部分の定義は次のとおりです。共通のカテゴリを共有するコレクションは、他のセクションで定義されています。 Attribute 14: archive 属性14:アーカイブ

TRUE, if this file has been archived since the time of last modification (deprecated in favor of time_backup).

このファイルが最後の変更時からアーカイブされている場合(time_backupを支持して廃止予定)。 Attribute 15: cansettime 属性15:CanSettime

TRUE, if the server is able to change the times for a file system object as specified in a SETATTR operation.

SETATTR操作で指定されているファイルシステムオブジェクトの時間をサーバーに変更できる場合は、TRUE。 Attribute 16: case_insensitive 属性16:case_insensitive.

TRUE, if file name comparisons on this file system are case insensitive.

このファイルシステムのファイル名の比較が大文字と小文字を区別しない場合はtrueです。 Attribute 17: case_preserving 属性17:CASE_PRESERVING

TRUE, if file name case on this file system is preserved.

このファイルシステムのファイル名の場合が保存されている場合は、trueです。 Attribute 60: change_policy 属性60:change_policy.

A value created by the server that the client can use to determine if some server policy related to the current file system has been subject to change. If the value remains the same, then the client can be sure that the values of the attributes related to fs location and the fss_type field of the fs_status attribute have not changed. On the other hand, a change in this value does necessarily imply a change in policy. It is up to the client to interrogate the server to determine if some policy relevant to it has changed. See Section 3.3.6 for details.


This attribute MUST change when the value returned by the fs_locations or fs_locations_info attribute changes, when a file system goes from read-only to writable or vice versa, or when the allowable set of security flavors for the file system or any part thereof is changed.

この属性は、ファイルシステムが読み取り専用から書き込み可能な、またはその逆の場合、またはファイルシステムまたはその一部のセキュリティフレーバーの許容範囲が変更されたときに、FS_LOCATIONATIONS_INFO属性によって返される値が変更されたときに変更する必要があります。 Attribute 18: chown_restricted 属性18:chown_restrictited

If TRUE, the server will reject any request to change either the owner or the group associated with a file if the caller is not a privileged user (for example, "root" in UNIX operating environments or, in Windows 2000, the "Take Ownership" privilege).

trueの場合、サーバーは、呼び出し元が特権ユーザーではない場合、またはファイルに関連付けられている所有者またはグループに関連付けられているグループ(UNIXオペレーティング環境の「ルート」など、またはWindows 2000では、「所有権を取得する」という要求を拒否します。"特権)。 Attribute 20: fileid 属性20:fileID

A number uniquely identifying the file within the file system.

ファイルシステム内のファイルを一意に識別する番号。 Attribute 21: files_avail 属性21:files_avail.

File slots available to this user on the file system containing this object -- this should be the smallest relevant limit.

このオブジェクトを含むファイルシステム上でこのユーザーが利用できるファイルスロット - これは関連する限界であるべきです。 Attribute 22: files_free 属性22:files_free.

Free file slots on the file system containing this object -- this should be the smallest relevant limit.

このオブジェクトを含むファイルシステム上の空きファイルスロット - これは最小の関連制限であるべきです。 Attribute 23: files_total 属性23:files_total

Total file slots on the file system containing this object.

このオブジェクトを含むファイルシステム上の合計ファイルスロット。 Attribute 76: fs_charset_cap 属性76:fs_charset_cap.

Character set capabilities for this file system. See Section 14.4.

このファイルシステムの文字セット機能。14.4節を参照してください。 Attribute 24: fs_locations 属性24:fs_locations.

Locations where this file system may be found. If the server returns NFS4ERR_MOVED as an error, this attribute MUST be supported. See Section 11.16 for more details.

このファイルシステムが見つかる可能性がある場所。サーバーがエラーとしてNFS4ERR_MOUDを返す場合、この属性はサポートされている必要があります。詳細については11.16項を参照してください。 Attribute 67: fs_locations_info 属性67:FS_LOCATIONS_INFO

Full function file system location. See Section 11.17.2 for more details.

フル機能ファイルの場所。詳細については11.17.2項を参照してください。 Attribute 61: fs_status 属性61:fs_status.

Generic file system type information. See Section 11.18 for more details.

一般ファイルシステムタイプ情報詳細については11.18項を参照してください。 Attribute 25: hidden 属性25:hidden.

TRUE, if the file is considered hidden with respect to the Windows API.

true、ファイルがWindows APIに関して非表示に見える場合。 Attribute 26: homogeneous 属性26:均質

TRUE, if this object's file system is homogeneous; i.e., all objects in the file system (all objects on the server with the same fsid) have common values for all per-file-system attributes.

このオブジェクトのファイルシステムが均質である場合はtrue。すなわち、ファイルシステム内のすべてのオブジェクト(同じFSIDを持つサーバー上のすべてのオブジェクト)には、ファイルごとの属性ごとに共通の値があります。 Attribute 27: maxfilesize 属性27:MaxFileSize

Maximum supported file size for the file system of this object.

このオブジェクトのファイルシステムのサポートされている最大ファイルサイズ。 Attribute 28: maxlink 属性28:MaxLink.

Maximum number of links for this object.

このオブジェクトの最大リンク数。 Attribute 29: maxname 属性29:MaxName.

Maximum file name size supported for this object.

このオブジェクトでサポートされている最大ファイル名サイズ。 Attribute 30: maxread 属性30:MaxRead.

Maximum amount of data the READ operation will return for this object.

最大データ読み取り操作はこのオブジェクトに戻ります。 Attribute 31: maxwrite 属性31:MaxWrite.

Maximum amount of data the WRITE operation will accept for this object. This attribute SHOULD be supported if the file is writable. Lack of this attribute can lead to the client either wasting bandwidth or not receiving the best performance.

最大データ書き込み操作はこのオブジェクトに対して受け入れます。この属性は、ファイルが書き込み可能な場合にサポートされます。この属性の欠如は、クライアントが帯域幅を無駄にするか、最良のパフォーマンスを受信していない可能性があります。 Attribute 32: mimetype 属性32:MimeType.

MIME body type/subtype of this object.

このオブジェクトのMIMEボディタイプ/サブタイプ。 Attribute 55: mounted_on_fileid 属性55:MACKIT_ON_FILEID

Like fileid, but if the target filehandle is the root of a file system, this attribute represents the fileid of the underlying directory.


UNIX-based operating environments connect a file system into the namespace by connecting (mounting) the file system onto the existing file object (the mount point, usually a directory) of an existing file system. When the mount point's parent directory is read via an API like readdir(), the return results are directory entries, each with a component name and a fileid. The fileid of the mount point's directory entry will be different from the fileid that the stat() system call returns. The stat() system call is returning the fileid of the root of the mounted file system, whereas readdir() is returning the fileid that stat() would have returned before any file systems were mounted on the mount point.


Unlike NFSv3, NFSv4.1 allows a client's LOOKUP request to cross other file systems. The client detects the file system crossing whenever the filehandle argument of LOOKUP has an fsid attribute different from that of the filehandle returned by LOOKUP. A UNIX-based client will consider this a "mount point crossing". UNIX has a legacy scheme for allowing a process to determine its current working directory. This relies on readdir() of a mount point's parent and stat() of the mount point returning fileids as previously described. The mounted_on_fileid attribute corresponds to the fileid that readdir() would have returned as described previously.


While the NFSv4.1 client could simply fabricate a fileid corresponding to what mounted_on_fileid provides (and if the server does not support mounted_on_fileid, the client has no choice), there is a risk that the client will generate a fileid that conflicts with one that is already assigned to another object in the file system. Instead, if the server can provide the mounted_on_fileid, the potential for client operational problems in this area is eliminated.


If the server detects that there is no mounted point at the target file object, then the value for mounted_on_fileid that it returns is the same as that of the fileid attribute.


The mounted_on_fileid attribute is RECOMMENDED, so the server SHOULD provide it if possible, and for a UNIX-based server, this is straightforward. Usually, mounted_on_fileid will be requested during a READDIR operation, in which case it is trivial (at least for UNIX-based servers) to return mounted_on_fileid since it is equal to the fileid of a directory entry returned by readdir(). If mounted_on_fileid is requested in a GETATTR operation, the server should obey an invariant that has it returning a value that is equal to the file object's entry in the object's parent directory, i.e., what readdir() would have returned. Some operating environments allow a series of two or more file systems to be mounted onto a single mount point. In this case, for the server to obey the aforementioned invariant, it will need to find the base mount point, and not the intermediate mount points.

mounted_on_fileid属性をお勧めしますので、サーバーは可能であれば、そしてUNIXベースのサーバーの場合、これは簡単です。通常、AllidDir操作中に搭載されています。これは、READDIR()によって返されるディレクトリエントリのfileIDと等しいため、(少なくともUNIXベースのサーバーの場合)では些細な(少なくともUNIXベースのサーバーの場合)。MACKIT_ON_FILEIDがGETATTRオペレーションで要求されている場合、サーバーは、オブジェクトの親ディレクトリ内のファイルオブジェクトのエントリ、すなわちREADDIR()が返された値に等しい値を返す不変権に従います。いくつかの動作環境では、一連の2つ以上のファイルシステムを単一のマウントポイントにマウントすることができます。この場合、サーバーが前述の不変に従うためには、中間マウントポイントではなく、ベースマウントポイントを見つける必要があります。 Attribute 34: no_trunc 属性34:NO_TRUNC

If this attribute is TRUE, then if the client uses a file name longer than name_max, an error will be returned instead of the name being truncated.

この属性がtrueの場合、クライアントがname_maxより長いファイル名を使用している場合は、切り捨てられている名前の代わりにエラーが返されます。 Attribute 35: numlinks 属性35:numlinks.

Number of hard links to this object.

このオブジェクトへのハードリンクの数。 Attribute 36: owner 属性36:所有者

The string name of the owner of this object.

このオブジェクトの所有者の文字列名。 Attribute 37: owner_group 属性37:owner_group.

The string name of the group ownership of this object.

このオブジェクトのグループ所有権の文字列名。 Attribute 38: quota_avail_hard 属性38:quota_avail_hard.

The value in bytes that represents the amount of additional disk space beyond the current allocation that can be allocated to this file or directory before further allocations will be refused. It is understood that this space may be consumed by allocations to other files or directories.

追加の割り当てを超えた追加のディスク容量を超える追加のディスク容量を表す値は、このファイルまたはディレクトリに割り当てることができます。その他の割り当てが拒否されます。このスペースは他のファイルまたはディレクトリへの割り当てによって消費される可能性があることが理解されます。 Attribute 39: quota_avail_soft 属性39:quota_avail_soft.

The value in bytes that represents the amount of additional disk space that can be allocated to this file or directory before the user may reasonably be warned. It is understood that this space may be consumed by allocations to other files or directories though there is a rule as to which other files or directories.

ユーザーが合理的に警告する前にこのファイルまたはディレクトリに割り当てることができる追加のディスク容量の量を表すバイト単位の値。このスペースは、他のファイルまたはディレクトリに関して規則があるが、他のファイルまたはディレクトリへの割り当てによって消費される可能性があることが理解される。 Attribute 40: quota_used 属性40:quota_used.

The value in bytes that represents the amount of disk space used by this file or directory and possibly a number of other similar files or directories, where the set of "similar" meets at least the criterion that allocating space to any file or directory in the set will reduce the "quota_avail_hard" of every other file or directory in the set.

このファイルまたはディレクトリによって使用されるディスク容量、およびおそらく他の類似のファイルやディレクトリの数を表す値の値は、少なくとも「類似」のセットが少なくとも任意のファイルまたはディレクトリに割り当てる基準を満たしています。セットは、セット内の他のすべてのファイルまたはディレクトリの "quota_avail_hard"を減らします。

Note that there may be a number of distinct but overlapping sets of files or directories for which a quota_used value is maintained, e.g., "all files with a given owner", "all files with a given group owner", etc. The server is at liberty to choose any of those sets when providing the content of the quota_used attribute, but should do so in a repeatable way. The rule may be configured per file system or may be "choose the set with the smallest quota".

Quota_USED値が維持されている、例えば「特定の所有者を持つすべてのファイル」、「特定のグループ所有者を持つすべてのファイル」などが維持されている、たくさんの異なるが重複するファイルまたはディレクトリが多数あることがあります。Quota_used属性の内容を提供するときは、これらのセットのいずれかを選択するためにLibertyで、繰り返し可能な方法でそうする必要があります。ルールはファイルシステムごとに設定されているか、「最小のクォータのセットを選択する」です。 Attribute 41: rawdev 属性41:RawDev.

Raw device number of file of type NF4BLK or NF4CHR. The device number is split into major and minor numbers. If the file's type attribute is not NF4BLK or NF4CHR, the value returned SHOULD NOT be considered useful.

RAWデバイスNF4BLKまたはNF4CHR型のファイル数。デバイス番号はメジャー番号とマイナー番号に分割されています。ファイルの種類属性がNF4BLKまたはNF4CHRではない場合、返される値は有用であると見なされるべきではありません。 Attribute 42: space_avail 属性42:space_avail.

Disk space in bytes available to this user on the file system containing this object -- this should be the smallest relevant limit.

このオブジェクトを含むファイルシステム上でこのユーザーが利用できるバイト単位のディスク容量 - これは最小の関連制限であるべきです。 Attribute 43: space_free 属性43:space_free.

Free disk space in bytes on the file system containing this object -- this should be the smallest relevant limit.

このオブジェクトを含むファイルシステム上のバイト単位の空きディスク容量 - これは最小の関連制限であるべきです。 Attribute 44: space_total 属性44:space_total

Total disk space in bytes on the file system containing this object.

このオブジェクトを含むファイルシステム上のバイト単位の全ディスク容量。 Attribute 45: space_used 属性45:space_used.

Number of file system bytes allocated to this object.

このオブジェクトに割り当てられているファイルシステムのバイト数。 Attribute 46: system 属性46:システム

This attribute is TRUE if this file is a "system" file with respect to the Windows operating environment.

この属性は、このファイルがWindowsオペレーティング環境に関する「システム」ファイルである場合にも当てはまります。 Attribute 47: time_access 属性47:time_access.

The time_access attribute represents the time of last access to the object by a READ operation sent to the server. The notion of what is an "access" depends on the server's operating environment and/or the server's file system semantics. For example, for servers obeying Portable Operating System Interface (POSIX) semantics, time_access would be updated only by the READ and READDIR operations and not any of the operations that modify the content of the object [13], [14], [15]. Of course, setting the corresponding time_access_set attribute is another way to modify the time_access attribute.


Whenever the file object resides on a writable file system, the server should make its best efforts to record time_access into stable storage. However, to mitigate the performance effects of doing so, and most especially whenever the server is satisfying the read of the object's content from its cache, the server MAY cache access time updates and lazily write them to stable storage. It is also acceptable to give administrators of the server the option to disable time_access updates.

ファイルオブジェクトが書き込み可能なファイルシステム上にあるときはいつでも、サーバーはTime_Accessを安定したストレージに記録するための最良の努力をしてください。ただし、SOのパフォーマンス効果を軽減するために、サーバーがそのキャッシュからオブジェクトのコンテンツの読み取りを満たしているときはいつでも、サーバーはアクセス時間の更新をキャッシュし、それらを安定したストレージに書き込むことができます。TIME_ACCESSの更新を無効にするオプションをサーバーの管理者に提供することもできます。 Attribute 48: time_access_set 属性48:time_access_set

Sets the time of last access to the object. SETATTR use only.

オブジェクトへの最後のアクセス時間を設定します。SetAttrのみ使用してください。 Attribute 49: time_backup 属性49:time_backup

The time of last backup of the object.

オブジェクトの最後のバックアップの時間。 Attribute 50: time_create 属性50:time_create

The time of creation of the object. This attribute does not have any relation to the traditional UNIX file attribute "ctime" or "change time".

オブジェクトの作成時。この属性には、従来のUNIXファイル属性「CTIME」または「変更時刻」との関係はありません。 Attribute 51: time_delta 属性51:time_delta

Smallest useful server time granularity.

最小の有用なサーバー時間の粒度。 Attribute 52: time_metadata 属性52:time_metadata

The time of last metadata modification of the object.

オブジェクトの最後のメタデータの変更の時間。 Attribute 53: time_modify 属性53:time_modify

The time of last modification to the object.

オブジェクトへの最後の変更の時間。 Attribute 54: time_modify_set 属性54:time_modify_set.

Sets the time of last modification to the object. SETATTR use only.


5.9. Interpreting owner and owner_group
5.9. 所有者とowner_groupの解釈

The RECOMMENDED attributes "owner" and "owner_group" (and also users and groups within the "acl" attribute) are represented in terms of a UTF-8 string. To avoid a representation that is tied to a particular underlying implementation at the client or server, the use of the UTF-8 string has been chosen. Note that Section 6.1 of RFC 2624 [53] provides additional rationale. It is expected that the client and server will have their own local representation of owner and owner_group that is used for local storage or presentation to the end user. Therefore, it is expected that when these attributes are transferred between the client and server, the local representation is translated to a syntax of the form "user@dns_domain". This will allow for a client and server that do not use the same local representation the ability to translate to a common syntax that can be interpreted by both.

推奨される属性 "owner"と "owner_group"(そして "acl"属性内のユーザーとグループ)は、UTF-8文字列の観点から表されます。クライアントまたはサーバーで特定の基礎となる実装に関連する表現を回避するために、UTF-8文字列の使用が選択されました。RFC 2624 [53]のセクション6.1は追加の根拠を提供することに留意されたい。クライアントとサーバーには、ローカルストレージやエンドユーザーへのプレゼンテーションに使用される所有者およびowner_groupの独自のローカル表現があります。したがって、これらの属性がクライアントとサーバー間で転送されると、ローカル表現は "user @ dns_domain"の形式の構文に変換されることが予想されます。これにより、同じローカル表現を使用しないクライアントとサーバーは、両方で解釈できる一般的な構文に変換する機能を使用することができます。

Similarly, security principals may be represented in different ways by different security mechanisms. Servers normally translate these representations into a common format, generally that used by local storage, to serve as a means of identifying the users corresponding to these security principals. When these local identifiers are translated to the form of the owner attribute, associated with files created by such principals, they identify, in a common format, the users associated with each corresponding set of security principals.


The translation used to interpret owner and group strings is not specified as part of the protocol. This allows various solutions to be employed. For example, a local translation table may be consulted that maps a numeric identifier to the user@dns_domain syntax. A name service may also be used to accomplish the translation. A server may provide a more general service, not limited by any particular translation (which would only translate a limited set of possible strings) by storing the owner and owner_group attributes in local storage without any translation or it may augment a translation method by storing the entire string for attributes for which no translation is available while using the local representation for those cases in which a translation is available.

所有者とグループ文字列を解釈するために使用される翻訳は、プロトコルの一部として指定されていません。これにより、様々な解決策を採用することができる。例えば、ローカル変換テーブルは、数値識別子をユーザ@ DNS_DOMAIN構文にマッピングするように調べることができる。翻訳を実行するためにネームサービスを使用することもできます。サーバは、翻訳なしで所有者および所有者および所有者の属性を格納することによって、所有者および所有者の属性を格納することによって、所有者および所有者の属性を格納することによって、限られた可能な文字列のセットを変換するだけであろう)によって制限されない一般的なサービスを提供することがある。翻訳が利用可能である場合のローカル表現の使用中に翻訳がない属性の文字列全体。

Servers that do not provide support for all possible values of the owner and owner_group attributes SHOULD return an error (NFS4ERR_BADOWNER) when a string is presented that has no translation, as the value to be set for a SETATTR of the owner, owner_group, or acl attributes. When a server does accept an owner or owner_group value as valid on a SETATTR (and similarly for the owner and group strings in an acl), it is promising to return that same string when a corresponding GETATTR is done. Configuration changes (including changes from the mapping of the string to the local representation) and ill-constructed name translations (those that contain aliasing) may make that promise impossible to honor. Servers should make appropriate efforts to avoid a situation in which these attributes have their values changed when no real change to ownership has occurred.


The "dns_domain" portion of the owner string is meant to be a DNS domain name, for example, Servers should accept as valid a set of users for at least one domain. A server may treat other domains as having no valid translations. A more general service is provided when a server is capable of accepting users for multiple domains, or for all domains, subject to security constraints.

OWNER文字列の "dns_domain"部分は、dnsドメイン名、たとえばuser@example.orgであることを意味します。サーバーは、少なくとも1つのドメインに対して有効なユーザーのセットとして受け入れる必要があります。サーバーは他のドメインを有効な翻訳なしのものとして扱うことがあります。サーバーが複数のドメインのユーザーを受け入れることができますが、セキュリティ制約の対象となるすべてのドメインの場合は、より一般的なサービスが提供されます。

In the case where there is no translation available to the client or server, the attribute value will be constructed without the "@". Therefore, the absence of the @ from the owner or owner_group attribute signifies that no translation was available at the sender and that the receiver of the attribute should not use that string as a basis for translation into its own internal format. Even though the attribute value cannot be translated, it may still be useful. In the case of a client, the attribute string may be used for local display of ownership.

クライアントまたはサーバーに翻訳が利用できない場合は、属性値が "@"なしで構築されます。したがって、所有者またはowner_group属性から@がないことは、送信者に翻訳が利用可能であり、属性の受信者がその文字列を翻訳の基礎として自らの内部形式に使用しないことを意味します。属性値を翻訳できないとしても、まだ役に立つ可能性があります。クライアントの場合、属性文字列は所有権のローカルディスプレイに使用できます。

To provide a greater degree of compatibility with NFSv3, which identified users and groups by 32-bit unsigned user identifiers and group identifiers, owner and group strings that consist of decimal numeric values with no leading zeros can be given a special interpretation by clients and servers that choose to provide such support. The receiver may treat such a user or group string as representing the same user as would be represented by an NFSv3 uid or gid having the corresponding numeric value. A server is not obligated to accept such a string, but may return an NFS4ERR_BADOWNER instead. To avoid this mechanism being used to subvert user and group translation, so that a client might pass all of the owners and groups in numeric form, a server SHOULD return an NFS4ERR_BADOWNER error when there is a valid translation for the user or owner designated in this way. In that case, the client must use the appropriate name@domain string and not the special form for compatibility.

32ビット符号なしユーザ識別子とグループ識別子とグループ識別子、主要な数値で構成されているユーザとグループとの互換性を高めるために、クライアントやサーバによる特別な解釈を与えることができるNFSV3との互換性を高くすることができる。それはそのようなサポートを提供することを選びます。受信機は、そのようなユーザまたはグループ文字列を、対応する数値を有するNFSv3 UIDまたはGIDによって表されるものと同じユーザを表すものとして扱うことができる。サーバーはそのような文字列を受け入れる義務はありませんが、代わりにNFS4ERR_BADOWNERを返すことがあります。このメカニズムを使用しないようにするために、ユーザーがすべての所有者とグループのすべての所有者とグループを数値形式で渡すことを避けるために、ユーザーまたはこれで指定された所有者の有効な翻訳がある場合は、サーバーがNFS4ERR_BADOWNERエラーを返す必要があります。仕方。その場合、クライアントは適切な名前の@ Domain文字列を使用する必要があります。互換性のための特別な形式ではありません。

The owner string "nobody" may be used to designate an anonymous user, which will be associated with a file created by a security principal that cannot be mapped through normal means to the owner attribute. Users and implementations of NFSv4.1 SHOULD NOT use "nobody" to designate a real user whose access is not anonymous.


5.10. Character Case Attributes
5.10. 文字ケース属性

With respect to the case_insensitive and case_preserving attributes, each UCS-4 character (which UTF-8 encodes) can be mapped according to Appendix B.2 of RFC 3454 [16]. For general character handling and internationalization issues, see Section 14.

Case_insensive属性とcase_preving属性に関して、各UCS-4文字(UTF-8エンコード)はRFC 3454 [16]の付録B.2に従ってマッピングできます。一般的な文字処理と国際化の問題については、14節を参照してください。

5.11. Directory Notification Attributes
5.11. ディレクトリ通知属性

As described in Section 18.39, the client can request a minimum delay for notifications of changes to attributes, but the server is free to ignore what the client requests. The client can determine in advance what notification delays the server will accept by sending a GETATTR operation for either or both of two directory notification attributes. When the client calls the GET_DIR_DELEGATION operation and asks for attribute change notifications, it should request notification delays that are no less than the values in the server-provided attributes.


5.11.1. Attribute 56: dir_notif_delay
5.11.1. 属性56:dir_notif_delay.

The dir_notif_delay attribute is the minimum number of seconds the server will delay before notifying the client of a change to the directory's attributes.


5.11.2. Attribute 57: dirent_notif_delay
5.11.2. 属性57:dirent_notif_delay

The dirent_notif_delay attribute is the minimum number of seconds the server will delay before notifying the client of a change to a file object that has an entry in the directory.


5.12. pNFS Attribute Definitions
5.12. PNFS属性定義
5.12.1. Attribute 62: fs_layout_type
5.12.1. 属性62:FS_LAYOUT_TYPE

The fs_layout_type attribute (see Section 3.3.13) applies to a file system and indicates what layout types are supported by the file system. When the client encounters a new fsid, the client SHOULD obtain the value for the fs_layout_type attribute associated with the new file system. This attribute is used by the client to determine if the layout types supported by the server match any of the client's supported layout types.


5.12.2. Attribute 66: layout_alignment
5.12.2. 属性66:layout_alignment.

When a client holds layouts on files of a file system, the layout_alignment attribute indicates the preferred alignment for I/O to files on that file system. Where possible, the client should send READ and WRITE operations with offsets that are whole multiples of the layout_alignment attribute.

クライアントがファイルシステムのファイルに対してレイアウトを保持すると、LAYOUT_ALIGNIGNT属性はそのファイルシステム上のI / Oのための優先アライメントを示します。可能であれば、クライアントは、Layout_alignment属性の倍数の倍数であるオフセットで読み書き操作を送信する必要があります。

5.12.3. Attribute 65: layout_blksize
5.12.3. 属性65:layout_blksize

When a client holds layouts on files of a file system, the layout_blksize attribute indicates the preferred block size for I/O to files on that file system. Where possible, the client should send READ operations with a count argument that is a whole multiple of layout_blksize, and WRITE operations with a data argument of size that is a whole multiple of layout_blksize.

クライアントがファイルシステムのファイルのレイアウトを保持すると、LAYOUT_BLKSIZE属性はそのファイルシステム上のファイルへのI / Oの優先ブロックサイズを示します。可能であれば、クライアントは、LAYOUT_BLKSIZEの倍数の倍数であるCount引数を使用して読み取り操作を送信し、Layout_BLKSIZEの倍数の倍数のデータ引数を使用して操作を書きます。

5.12.4. Attribute 63: layout_hint
5.12.4. 属性63:layout_hint

The layout_hint attribute (see Section 3.3.19) may be set on newly created files to influence the metadata server's choice for the file's layout. If possible, this attribute is one of those set in the initial attributes within the OPEN operation. The metadata server may choose to ignore this attribute. The layout_hint attribute is a subset of the layout structure returned by LAYOUTGET. For example, instead of specifying particular devices, this would be used to suggest the stripe width of a file. The server implementation determines which fields within the layout will be used.


5.12.5. Attribute 64: layout_type
5.12.5. 属性64:LAYOUT_TYPE

This attribute lists the layout type(s) available for a file. The value returned by the server is for informational purposes only. The client will use the LAYOUTGET operation to obtain the information needed in order to perform I/O, for example, the specific device information for the file and its layout.

この属性は、ファイルに使用可能なレイアウトタイプを一覧表示します。サーバーによって返される値は情報提供のみを目的としています。クライアントは、ファイルの特定のデバイス情報とそのレイアウトなど、I / Oを実行するために必要な情報を取得するためにレイアウト操作を使用します。

5.12.6. Attribute 68: mdsthreshold
5.12.6. 属性68:MDSTHRESHOLD

This attribute is a server-provided hint used to communicate to the client when it is more efficient to send READ and WRITE operations to the metadata server or the data server. The two types of thresholds described are file size thresholds and I/O size thresholds. If a file's size is smaller than the file size threshold, data accesses SHOULD be sent to the metadata server. If an I/O request has a length that is below the I/O size threshold, the I/O SHOULD be sent to the metadata server. Each threshold type is specified separately for read and write.

この属性は、メタデータサーバーまたはデータサーバーに読み書き操作を送信するのが効率的である場合に、クライアントと通信するために使用されるサーバー提供のヒントです。記載されている2種類のしきい値は、ファイルサイズのしきい値とI / Oサイズのしきい値です。ファイルのサイズがファイルサイズしきい値より小さい場合、データアクセスはメタデータサーバーに送信されます。I / O要求にI / Oサイズしきい値を下回る長さがある場合は、I / Oをメタデータサーバーに送信する必要があります。各しきい値タイプは、読み書きのために別々に指定されます。

The server MAY provide both types of thresholds for a file. If both file size and I/O size are provided, the client SHOULD reach or exceed both thresholds before sending its read or write requests to the data server. Alternatively, if only one of the specified thresholds is reached or exceeded, the I/O requests are sent to the metadata server.

サーバーは、ファイルの両方のタイプのしきい値を提供できます。ファイルサイズとI / Oサイズの両方が提供されている場合、クライアントは両方のしきい値に達するか、データサーバへの読み取りまたは書き込み要求を送信する必要があります。あるいは、指定されたしきい値のうちの1つだけを超えている場合は、I / O要求がメタデータサーバーに送信されます。

For each threshold type, a value of zero indicates no READ or WRITE should be sent to the metadata server, while a value of all ones indicates that all READs or WRITEs should be sent to the metadata server.


The attribute is available on a per-filehandle basis. If the current filehandle refers to a non-pNFS file or directory, the metadata server should return an attribute that is representative of the filehandle's file system. It is suggested that this attribute is queried as part of the OPEN operation. Due to dynamic system changes, the client should not assume that the attribute will remain constant for any specific time period; thus, it should be periodically refreshed.


5.13. Retention Attributes
5.13. 保持属性

Retention is a concept whereby a file object can be placed in an immutable, undeletable, unrenamable state for a fixed or infinite duration of time. Once in this "retained" state, the file cannot be moved out of the state until the duration of retention has been reached.


When retention is enabled, retention MUST extend to the data of the file, and the name of file. The server MAY extend retention to any other property of the file, including any subset of REQUIRED, RECOMMENDED, and named attributes, with the exceptions noted in this section.


Servers MAY support or not support retention on any file object type.


The five retention attributes are explained in the next subsections.


5.13.1. Attribute 69: retention_get
5.13.1. 属性69:retention_get.

If retention is enabled for the associated file, this attribute's value represents the retention begin time of the file object. This attribute's value is only readable with the GETATTR operation and MUST NOT be modified by the SETATTR operation (Section 5.5). The value of the attribute consists of:


   const RET4_DURATION_INFINITE    = 0xffffffffffffffff;
   struct retention_get4 {
           uint64_t        rg_duration;
           nfstime4        rg_begin_time<1>;

The field rg_duration is the duration in seconds indicating how long the file will be retained once retention is enabled. The field rg_begin_time is an array of up to one absolute time value. If the array is zero length, no beginning retention time has been established, and retention is not enabled. If rg_duration is equal to RET4_DURATION_INFINITE, the file, once retention is enabled, will be retained for an infinite duration.


If (as soon as) rg_duration is zero, then rg_begin_time will be of zero length, and again, retention is not (no longer) enabled.


5.13.2. Attribute 70: retention_set
5.13.2. 属性70:retention_set.

This attribute is used to set the retention duration and optionally enable retention for the associated file object. This attribute is only modifiable via the SETATTR operation and MUST NOT be retrieved by the GETATTR operation (Section 5.5). This attribute corresponds to retention_get. The value of the attribute consists of:


   struct retention_set4 {
           bool            rs_enable;
           uint64_t        rs_duration<1>;

If the client sets rs_enable to TRUE, then it is enabling retention on the file object with the begin time of retention starting from the server's current time and date. The duration of the retention can also be provided if the rs_duration array is of length one. The duration is the time in seconds from the begin time of retention, and if set to RET4_DURATION_INFINITE, the file is to be retained forever. If retention is enabled, with no duration specified in either this SETATTR or a previous SETATTR, the duration defaults to zero seconds. The server MAY restrict the enabling of retention or the duration of retention on the basis of the ACE4_WRITE_RETENTION ACL permission. The enabling of retention MUST NOT prevent the enabling of event-based retention or the modification of the retention_hold attribute.


The following rules apply to both the retention_set and retentevt_set attributes.


* As long as retention is not enabled, the client is permitted to decrease the duration.

* 保持が有効になっていない限り、クライアントは期間を短縮することができます。

* The duration can always be set to an equal or higher value, even if retention is enabled. Note that once retention is enabled, the actual duration (as returned by the retention_get or retentevt_get attributes; see Section 5.13.1 or Section 5.13.3) is constantly counting down to zero (one unit per second), unless the duration was set to RET4_DURATION_INFINITE. Thus, it will not be possible for the client to precisely extend the duration on a file that has retention enabled.

* 保持が有効になっていても、期間は常に等しい値に設定できます。一度保持が有効になっていると、実際の期間(retention_getまたはretentevt_get属性によって返されるように。セクション5.13.1またはセクション5.13.3を参照)が、期間が設定されていない限り、常にゼロにカウントダウンされています(1秒あたり1秒間)、ret4_duration_infinite。したがって、クライアントが保持が有効になっているファイル上の期間を正確に拡張することは不可能であろう。

* While retention is enabled, attempts to disable retention or decrease the retention's duration MUST fail with the error NFS4ERR_INVAL.

* 保存が有効になっている間は、保存期間を無効にしたり、保存期間を削減しようとしました。

* If the principal attempting to change retention_set or retentevt_set does not have ACE4_WRITE_RETENTION permissions, the attempt MUST fail with NFS4ERR_ACCESS.

* retention_setまたはretentevt_setを変更しようとしたプリンシパルがACE4_WRITE_RETENTION権限を持っていない場合、その試行はNFS4ERR_ACCESSで失敗する必要があります。

5.13.3. Attribute 71: retentevt_get
5.13.3. 属性71:retentevt_get

Gets the event-based retention duration, and if enabled, the event-based retention begin time of the file object. This attribute is like retention_get, but refers to event-based retention. The event that triggers event-based retention is not defined by the NFSv4.1 specification.


5.13.4. Attribute 72: retentevt_set
5.13.4. 属性72:retentevt_set.

Sets the event-based retention duration, and optionally enables event-based retention on the file object. This attribute corresponds to retentevt_get and is like retention_set, but refers to event-based retention. When event-based retention is set, the file MUST be retained even if non-event-based retention has been set, and the duration of non-event-based retention has been reached. Conversely, when non-event-based retention has been set, the file MUST be retained even if event-based retention has been set, and the duration of event-based retention has been reached. The server MAY restrict the enabling of event-based retention or the duration of event-based retention on the basis of the ACE4_WRITE_RETENTION ACL permission. The enabling of event-based retention MUST NOT prevent the enabling of non-event-based retention or the modification of the retention_hold attribute.


5.13.5. Attribute 73: retention_hold
5.13.5. 属性73:retention_hold.

Gets or sets administrative retention holds, one hold per bit position.


This attribute allows one to 64 administrative holds, one hold per bit on the attribute. If retention_hold is not zero, then the file MUST NOT be deleted, renamed, or modified, even if the duration on enabled event or non-event-based retention has been reached. The server MAY restrict the modification of retention_hold on the basis of the ACE4_WRITE_RETENTION_HOLD ACL permission. The enabling of administration retention holds does not prevent the enabling of event-based or non-event-based retention.

この属性により、1対64の管理者が属性に1つずつ保持されます。retension_holdがゼロではない場合、有効なイベントまたは非イベントベースの保存期間に到達した期間に達しても、ファイルは削除、名前変更、または変更されてはいけません。サーバは、ACE4_WRITE_RETENTION_HOLE ACL権限に基づいて、retention_holdの変更を制限することができる。管理保持の有効化は、イベントベースまたは非イベントベースの保持の有効化を妨げません。

If the principal attempting to change retention_hold does not have ACE4_WRITE_RETENTION_HOLD permissions, the attempt MUST fail with NFS4ERR_ACCESS.


6. Access Control Attributes
6. アクセス制御属性

Access Control Lists (ACLs) are file attributes that specify fine-grained access control. This section covers the "acl", "dacl", "sacl", "aclsupport", "mode", and "mode_set_masked" file attributes and their interactions. Note that file attributes may apply to any file system object.


6.1. Goals
6.1. 目標

ACLs and modes represent two well-established models for specifying permissions. This section specifies requirements that attempt to meet the following goals:


* If a server supports the mode attribute, it should provide reasonable semantics to clients that only set and retrieve the mode attribute.

* サーバーがMODE属性をサポートしている場合は、MODE属性を設定および取得するクライアントに合理的なセマンティクスを提供する必要があります。

* If a server supports ACL attributes, it should provide reasonable semantics to clients that only set and retrieve those attributes.

* サーバーがACL属性をサポートしている場合は、それらの属性を設定および取得するクライアントに合理的なセマンティクスを提供する必要があります。

* On servers that support the mode attribute, if ACL attributes have never been set on an object, via inheritance or explicitly, the behavior should be traditional UNIX-like behavior.

* MODE属性をサポートするサーバー上で、ACL属性は、継承または明示的にオブジェクトに設定されていない場合、動作は従来のUNIXのような動作になります。

* On servers that support the mode attribute, if the ACL attributes have been previously set on an object, either explicitly or via inheritance:

* MODE属性をサポートするサーバー上で、ACL属性が以前にオブジェクトに設定されている場合は、明示的にまたは継承を介して次のように設定されています。

- Setting only the mode attribute should effectively control the traditional UNIX-like permissions of read, write, and execute on owner, owner_group, and other.

- MODE属性のみを設定すると、OWNER、OWNER_GROUPなどのREAD、WRITE、EXECUTEの従来のUNIX様の権限を効果的に制御する必要があります。

- Setting only the mode attribute should provide reasonable security. For example, setting a mode of 000 should be enough to ensure that future OPEN operations for OPEN4_SHARE_ACCESS_READ or OPEN4_SHARE_ACCESS_WRITE by any principal fail, regardless of a previously existing or inherited ACL.

- モード属性のみを設定すると、合理的なセキュリティを提供する必要があります。たとえば、000モードを設定するには、以前に存在しているか継承されたACLに関係なく、任意のプリンシパルによるOpen4_Share_access_ReadまたはOpen4_Share_access_Writeの将来のオープン操作が確実に失敗するのに十分なはずです。

* NFSv4.1 may introduce different semantics relating to the mode and ACL attributes, but it does not render invalid any previously existing implementations. Additionally, this section provides clarifications based on previous implementations and discussions around them.

* NFSV4.1は、モードおよびACL属性に関する異なるセマンティクスを導入することができますが、以前に既存の実装を無効にしません。さらに、このセクションでは、以前の実装とそれらの周囲の議論に基づく明確化を説明します。

* On servers that support both the mode and the acl or dacl attributes, the server must keep the two consistent with each other. The value of the mode attribute (with the exception of the three high-order bits described in Section 6.2.4) must be determined entirely by the value of the ACL, so that use of the mode is never required for anything other than setting the three high-order bits. See Section 6.4.1 for exact requirements.

* モードとACLまたはDACL属性の両方をサポートするサーバー上で、サーバーは2つを互いに一貫して保持しなければなりません。MODE属性の値(セクション6.2.4で説明されている3つの上位ビットを除く)はACLの値によって完全に決定されなければならず、そのためモードの使用は設定以外のものには必要ありません。3つの高次ビット正確な要件については6.4.1項を参照してください。

* When a mode attribute is set on an object, the ACL attributes may need to be modified in order to not conflict with the new mode. In such cases, it is desirable that the ACL keep as much information as possible. This includes information about inheritance, AUDIT and ALARM ACEs, and permissions granted and denied that do not conflict with the new mode.

* モード属性がオブジェクトに設定されている場合は、新しいモードと競合しないようにACL属性を変更する必要があります。そのような場合、ACLができるだけ多くの情報を保持することが望ましい。これには、継承、監査、およびアラームACEの情報、および新しいモードと競合しない権限と拒否された権限に関する情報が含まれます。

6.2. File Attributes Discussion
6.2. ファイル属性ディスカッション
6.2.1. Attribute 12: acl
6.2.1. 属性12:ACL.

The NFSv4.1 ACL attribute contains an array of Access Control Entries (ACEs) that are associated with the file system object. Although the client can set and get the acl attribute, the server is responsible for using the ACL to perform access control. The client can use the OPEN or ACCESS operations to check access without modifying or reading data or metadata.

NFSV4.1 ACL属性には、ファイルシステムオブジェクトに関連付けられているアクセス制御エントリの配列(ACE)が含まれています。クライアントはACL属性を設定および取得することができますが、サーバーはACLを使用してアクセス制御を実行します。クライアントは、データやメタデータを変更または読み取ることなくアクセスを確認するためにオープンまたはアクセス操作を使用できます。

The NFS ACE structure is defined as follows:

NFS ACE構造体は次のように定義されています。

typedef uint32_t acetype4;

typedef uint32_t ateratype4。

typedef uint32_t aceflag4;

typedef uint32_t acflag4;

typedef uint32_t acemask4;

typedef uint32_t a atemask4;

   struct nfsace4 {
           acetype4        type;
           aceflag4        flag;
           acemask4        access_mask;
           utf8str_mixed   who;

To determine if a request succeeds, the server processes each nfsace4 entry in order. Only ACEs that have a "who" that matches the requester are considered. Each ACE is processed until all of the bits of the requester's access have been ALLOWED. Once a bit (see below) has been ALLOWED by an ACCESS_ALLOWED_ACE, it is no longer considered in the processing of later ACEs. If an ACCESS_DENIED_ACE is encountered where the requester's access still has unALLOWED bits in common with the "access_mask" of the ACE, the request is denied. When the ACL is fully processed, if there are bits in the requester's mask that have not been ALLOWED or DENIED, access is denied.


Unlike the ALLOW and DENY ACE types, the ALARM and AUDIT ACE types do not affect a requester's access, and instead are for triggering events as a result of a requester's access attempt. Therefore, AUDIT and ALARM ACEs are processed only after processing ALLOW and DENY ACEs.

ALLY ACEタイプとは異なり、アラームと監査ACEタイプはリクエスタのアクセスには影響しません。代わりに、リクエスタのアクセス試行の結果としてイベントをトリガするためのものです。したがって、監査およびアラームACEは、処理が許可され、ACEを拒否した後にのみ処理されます。

The NFSv4.1 ACL model is quite rich. Some server platforms may provide access-control functionality that goes beyond the UNIX-style mode attribute, but that is not as rich as the NFS ACL model. So that users can take advantage of this more limited functionality, the server may support the acl attributes by mapping between its ACL model and the NFSv4.1 ACL model. Servers must ensure that the ACL they actually store or enforce is at least as strict as the NFSv4 ACL that was set. It is tempting to accomplish this by rejecting any ACL that falls outside the small set that can be represented accurately. However, such an approach can render ACLs unusable without special client-side knowledge of the server's mapping, which defeats the purpose of having a common NFSv4 ACL protocol. Therefore, servers should accept every ACL that they can without compromising security. To help accomplish this, servers may make a special exception, in the case of unsupported permission bits, to the rule that bits not ALLOWED or DENIED by an ACL must be denied. For example, a UNIX-style server might choose to silently allow read attribute permissions even though an ACL does not explicitly allow those permissions. (An ACL that explicitly denies permission to read attributes should still be rejected.)

NFSV4.1 ACLモデルはかなり豊富です。一部のサーバープラットフォームは、UNIXスタイルモード属性を超えてアクセス制御機能を提供できますが、NFS ACLモデルと同じくらい豊富ではありません。ユーザーがこのより限られた機能を利用できるように、サーバーはACLモデルとNFSV4.1 ACLモデルの間のマッピングによってACL属性をサポートできます。サーバーは、実際に保存または適用しているACLが設定されたNFSv4 ACLと少なくとも厳密であることを確認する必要があります。正確に表すことができる小型セットの外側にあるACLを拒絶することによってこれを達成することを魅力的です。しかしながら、そのようなアプローチは、サーバのマッピングに関する特別なクライアント側の知識なしにACLを使用できなくなる可能性があり、これは一般的なNFSV4 ACLプロトコルを有することの目的を軽減する。したがって、サーバーはセキュリティを犠牲にすることなくできるすべてのACLを受け入れる必要があります。これを達成するのを助けるために、サーバーは、サポートされていない権限ビットの場合、ビットが許可されていないか、またはACLによって拒否されたルールに特別な例外を作成することができます。たとえば、UNIXスタイルのサーバーは、ACLがそれらの権限を明示的に許可しない場合でも、読み取り属性のアクセス許可を静的に許可することを選択できます。 (明示的に属性を読み取る許可を拒否するACLは依然として拒否されるべきです。)

The situation is complicated by the fact that a server may have multiple modules that enforce ACLs. For example, the enforcement for NFSv4.1 access may be different from, but not weaker than, the enforcement for local access, and both may be different from the enforcement for access through other protocols such as SMB (Server Message Block). So it may be useful for a server to accept an ACL even if not all of its modules are able to support it.


The guiding principle with regard to NFSv4 access is that the server must not accept ACLs that appear to make access to the file more restrictive than it really is.

NFSV4アクセスに関するガイド原則は、サーバーが本当に制限的なものよりも制限的なファイルにアクセスするように見えるACLを受け入れてはいけません。 ACE Type エースタイプ

The constants used for the type field (acetype4) are as follows:


   const ACE4_ACCESS_ALLOWED_ACE_TYPE      = 0x00000000;
   const ACE4_ACCESS_DENIED_ACE_TYPE       = 0x00000001;
   const ACE4_SYSTEM_AUDIT_ACE_TYPE        = 0x00000002;
   const ACE4_SYSTEM_ALARM_ACE_TYPE        = 0x00000003;

Only the ALLOWED and DENIED bits may be used in the dacl attribute, and only the AUDIT and ALARM bits may be used in the sacl attribute. All four are permitted in the acl attribute.


   | Value                        | Abbreviation | Description         |
   | ACE4_ACCESS_ALLOWED_ACE_TYPE | ALLOW        | Explicitly grants   |
   |                              |              | the access          |
   |                              |              | defined in          |
   |                              |              | acemask4 to the     |
   |                              |              | file or             |
   |                              |              | directory.          |
   | ACE4_ACCESS_DENIED_ACE_TYPE  | DENY         | Explicitly denies   |
   |                              |              | the access          |
   |                              |              | defined in          |
   |                              |              | acemask4 to the     |
   |                              |              | file or             |
   |                              |              | directory.          |
   | ACE4_SYSTEM_AUDIT_ACE_TYPE   | AUDIT        | Log (in a system-   |
   |                              |              | dependent way)      |
   |                              |              | any access          |
   |                              |              | attempt to a file   |
   |                              |              | or directory that   |
   |                              |              | uses any of the     |
   |                              |              | access methods      |
   |                              |              | specified in        |
   |                              |              | acemask4.           |
   | ACE4_SYSTEM_ALARM_ACE_TYPE   | ALARM        | Generate an alarm   |
   |                              |              | (in a system-       |
   |                              |              | dependent way)      |
   |                              |              | when any access     |
   |                              |              | attempt is made     |
   |                              |              | to a file or        |
   |                              |              | directory for the   |
   |                              |              | access methods      |
   |                              |              | specified in        |
   |                              |              | acemask4.           |

Table 6


The "Abbreviation" column denotes how the types will be referred to throughout the rest of this section.

「略語」列は、このセクションの残りの部分を通してタイプの種類をどのように参照するかを示します。 Attribute 13: aclsupport 属性13:ACLSupport.

A server need not support all of the above ACE types. This attribute indicates which ACE types are supported for the current file system. The bitmask constants used to represent the above definitions within the aclsupport attribute are as follows:


   const ACL4_SUPPORT_ALLOW_ACL    = 0x00000001;
   const ACL4_SUPPORT_DENY_ACL     = 0x00000002;
   const ACL4_SUPPORT_AUDIT_ACL    = 0x00000004;
   const ACL4_SUPPORT_ALARM_ACL    = 0x00000008;

Servers that support either the ALLOW or DENY ACE type SHOULD support both ALLOW and DENY ACE types.

許可または拒否ACEタイプをサポートするサーバーは、ALLY ACEタイプと拒否の両方をサポートする必要があります。

Clients should not attempt to set an ACE unless the server claims support for that ACE type. If the server receives a request to set an ACE that it cannot store, it MUST reject the request with NFS4ERR_ATTRNOTSUPP. If the server receives a request to set an ACE that it can store but cannot enforce, the server SHOULD reject the request with NFS4ERR_ATTRNOTSUPP.


Support for any of the ACL attributes is optional (albeit RECOMMENDED). However, a server that supports either of the new ACL attributes (dacl or sacl) MUST allow use of the new ACL attributes to access all of the ACE types that it supports. In other words, if such a server supports ALLOW or DENY ACEs, then it MUST support the dacl attribute, and if it supports AUDIT or ALARM ACEs, then it MUST support the sacl attribute.

いずれかのACL属性のサポートはオプションです(推奨されています)。ただし、新しいACL属性(DACLまたはSACL)のいずれかをサポートするサーバーは、新しいACL属性を使用してサポートしているすべてのACEタイプにアクセスする必要があります。言い換えれば、そのようなサーバーがACEを許可または拒否している場合は、DACL属性をサポートしており、監査またはアラームACESをサポートしている場合はSACL属性をサポートしている必要があります。 ACE Access Mask ACEアクセスマスク

The bitmask constants used for the access mask field are as follows:


   const ACE4_READ_DATA            = 0x00000001;
   const ACE4_LIST_DIRECTORY       = 0x00000001;
   const ACE4_WRITE_DATA           = 0x00000002;
   const ACE4_ADD_FILE             = 0x00000002;
   const ACE4_APPEND_DATA          = 0x00000004;
   const ACE4_ADD_SUBDIRECTORY     = 0x00000004;
   const ACE4_READ_NAMED_ATTRS     = 0x00000008;
   const ACE4_WRITE_NAMED_ATTRS    = 0x00000010;
   const ACE4_EXECUTE              = 0x00000020;
   const ACE4_DELETE_CHILD         = 0x00000040;
   const ACE4_READ_ATTRIBUTES      = 0x00000080;
   const ACE4_WRITE_ATTRIBUTES     = 0x00000100;
   const ACE4_WRITE_RETENTION      = 0x00000200;
   const ACE4_WRITE_RETENTION_HOLD = 0x00000400;
   const ACE4_DELETE               = 0x00010000;
   const ACE4_READ_ACL             = 0x00020000;
   const ACE4_WRITE_ACL            = 0x00040000;
   const ACE4_WRITE_OWNER          = 0x00080000;
   const ACE4_SYNCHRONIZE          = 0x00100000;

Note that some masks have coincident values, for example, ACE4_READ_DATA and ACE4_LIST_DIRECTORY. The mask entries ACE4_LIST_DIRECTORY, ACE4_ADD_FILE, and ACE4_ADD_SUBDIRECTORY are intended to be used with directory objects, while ACE4_READ_DATA, ACE4_WRITE_DATA, and ACE4_APPEND_DATA are intended to be used with non-directory objects.

いくつかのマスクは、例えば、ACE4_READ_DATAおよびace4_list_directoryなどの一致値を持ちます。マスクエントリACE4_LIST_DIRECTORY、ACE4_ADD_FILE、およびACE4_ADD_SUBDIRECTORYはディレクトリオブジェクトと共に使用されることを意図していますが、ACE4_READ_DATA、ACE4_WRITE_DATA、およびACE4_APPEND_DATAは、ディレクトリ以外のオブジェクトで使用されることを目的としています。 Discussion of Mask Attributes マスク属性の説明



Operation(s) affected: READ




Discussion: Permission to read the data of the file.


Servers SHOULD allow a user the ability to read the data of the file when only the ACE4_EXECUTE access mask bit is allowed.

サーバーは、ACE4_EXECUTE ACCESS MASKビットのみが許可されている場合にファイルのデータを読み取る機能をユーザーに許可する必要があります。



Operation(s) affected: READDIR


Discussion: Permission to list the contents of a directory.




Operation(s) affected: WRITE




SETATTR of size


Discussion: Permission to modify a file's data.




Operation(s) affected: CREATE







ren ren

Discussion: Permission to add a new file in a directory. The CREATE operation is affected when nfs_ftype4 is NF4LNK, NF4BLK, NF4CHR, NF4SOCK, or NF4FIFO. (NF4DIR is not listed because it is covered by ACE4_ADD_SUBDIRECTORY.) OPEN is affected when used to create a regular file. LINK and RENAME are always affected.




Operation(s) affected: WRITE




SETATTR of size


Discussion: The ability to modify a file's data, but only starting at EOF. This allows for the notion of append-only files, by allowing ACE4_APPEND_DATA and denying ACE4_WRITE_DATA to the same user or group. If a file has an ACL such as the one described above and a WRITE request is made for somewhere other than EOF, the server SHOULD return NFS4ERR_ACCESS.




Operation(s) affected: CREATE



ren ren

Discussion: Permission to create a subdirectory in a directory. The CREATE operation is affected when nfs_ftype4 is NF4DIR. The RENAME operation is always affected.




Operation(s) affected: OPENATTR


Discussion: Permission to read the named attributes of a file or to look up the named attribute directory. OPENATTR is affected when it is not used to create a named attribute directory. This is when 1) createdir is TRUE, but a named attribute directory already exists, or 2) createdir is FALSE.




Operation(s) affected: OPENATTR


Discussion: Permission to write the named attributes of a file or to create a named attribute directory. OPENATTR is affected when it is used to create a named attribute directory. This is when createdir is TRUE and no named attribute directory exists. The ability to check whether or not a named attribute directory exists depends on the ability to look it up; therefore, users also need the ACE4_READ_NAMED_ATTRS permission in order to create a named attribute directory.




Operation(s) affected: READ







ren ren





Discussion: Permission to execute a file.


Servers SHOULD allow a user the ability to read the data of the file when only the ACE4_EXECUTE access mask bit is allowed. This is because there is no way to execute a file without reading the contents. Though a server may treat ACE4_EXECUTE and ACE4_READ_DATA bits identically when deciding to permit a READ operation, it SHOULD still allow the two bits to be set independently in ACLs, and MUST distinguish between them when replying to ACCESS operations. In particular, servers SHOULD NOT silently turn on one of the two bits when the other is set, as that would make it impossible for the client to correctly enforce the distinction between read and execute permissions.

サーバーは、ACE4_EXECUTE ACCESS MASKビットのみが許可されている場合にファイルのデータを読み取る機能をユーザーに許可する必要があります。内容を読むことなくファイルを実行する方法がないためです。読み取り操作を許可するように決定するときは、サーバーはICE4_EXECUTEおよびACE4_READ_DATAビットを同じように扱うことができますが、2ビットをACLで独立して設定することもできます。アクセス操作に返信するときにそれらを区別する必要があります。特に、サーバーは、他方が設定されているときに2ビットのうちの1つを静かにしてはいけません。これにより、クライアントが読み取りアクセス許可と実行許可の間の区別を正しく適用できなくなります。

As an example, following a SETATTR of the following ACL:




A subsequent GETATTR of ACL for that file SHOULD return:




Rather than:





Operation(s) affected: LOOKUP


Discussion: Permission to traverse/search a directory.




Operation(s) affected: REMOVE



ren ren

Discussion: Permission to delete a file or directory within a directory. See Section for information on ACE4_DELETE and ACE4_DELETE_CHILD interact.

ディスカッション:ディレクトリ内のファイルまたはディレクトリを削除する権限。ACE4_DELETEおよびACE4_DELETE_CHILD INTORACTについては、項を参照してください。



Operation(s) affected: GETATTR of file system object attributes





n n



Discussion: The ability to read basic attributes (non-ACLs) of a file. On a UNIX system, basic attributes can be thought of as the stat-level attributes. Allowing this access mask bit would mean that the entity can execute "ls -l" and stat. If a READDIR operation requests attributes, this mask must be allowed for the READDIR to succeed.

ディスカッション:ファイルの基本属性(ACL以外)を読み取る機能。UNIXシステムでは、基本属性をSTATレベル属性として考えることができます。このアクセスマスクビットを許可すると、エンティティは "LS -L"とstatを実行できることを意味します。READDIRオペレーションが属性を要求した場合、READDIRが成功するためにこのマスクを許可する必要があります。



Operation(s) affected: SETATTR of time_access_set, time_backup,


time_create, time_modify_set, mimetype, hidden, system


Discussion: Permission to change the times associated with a file or directory to an arbitrary value. Also permission to change the mimetype, hidden, and system attributes. A user having ACE4_WRITE_DATA or ACE4_WRITE_ATTRIBUTES will be allowed to set the times associated with a file to the current server time.




Operation(s) affected: SETATTR of retention_set, retentevt_set.


Discussion: Permission to modify the durations of event and non-event-based retention. Also permission to enable event and non-event-based retention. A server MAY behave such that setting ACE4_WRITE_ATTRIBUTES allows ACE4_WRITE_RETENTION.




Operation(s) affected: SETATTR of retention_hold.


Discussion: Permission to modify the administration retention holds. A server MAY map ACE4_WRITE_ATTRIBUTES to ACE_WRITE_RETENTION_HOLD.




Operation(s) affected: REMOVE


Discussion: Permission to delete the file or directory. See Section for information on ACE4_DELETE and ACE4_DELETE_CHILD interact.

ディスカッション:ファイルまたはディレクトリを削除する権限。ACE4_DELETEおよびACE4_DELETE_CHILD INTORACTについては、項を参照してください。



Operation(s) affected: GETATTR of acl, dacl, or sacl



n n



Discussion: Permission to read the ACL.




Operation(s) affected: SETATTR of acl and mode


Discussion: Permission to write the acl and mode attributes.




Operation(s) affected: SETATTR of owner and owner_group


Discussion: Permission to write the owner and owner_group attributes. On UNIX systems, this is the ability to execute chown() and chgrp().




Operation(s) affected: NONE


Discussion: Permission to use the file object as a synchronization primitive for interprocess communication. This permission is not enforced or interpreted by the NFSv4.1 server on behalf of the client.


Typically, the ACE4_SYNCHRONIZE permission is only meaningful on local file systems, i.e., file systems not accessed via NFSv4.1. The reason that the permission bit exists is that some operating environments, such as Windows, use ACE4_SYNCHRONIZE.


For example, if a client copies a file that has ACE4_SYNCHRONIZE set from a local file system to an NFSv4.1 server, and then later copies the file from the NFSv4.1 server to a local file system, it is likely that if ACE4_SYNCHRONIZE was set in the original file, the client will want it set in the second copy. The first copy will not have the permission set unless the NFSv4.1 server has the means to set the ACE4_SYNCHRONIZE bit. The second copy will not have the permission set unless the NFSv4.1 server has the means to retrieve the ACE4_SYNCHRONIZE bit.


Server implementations need not provide the granularity of control that is implied by this list of masks. For example, POSIX-based systems might not distinguish ACE4_APPEND_DATA (the ability to append to a file) from ACE4_WRITE_DATA (the ability to modify existing contents); both masks would be tied to a single "write" permission [17]. When such a server returns attributes to the client, it would show both ACE4_APPEND_DATA and ACE4_WRITE_DATA if and only if the write permission is enabled.


If a server receives a SETATTR request that it cannot accurately implement, it should err in the direction of more restricted access, except in the previously discussed cases of execute and read. For example, suppose a server cannot distinguish overwriting data from appending new data, as described in the previous paragraph. If a client submits an ALLOW ACE where ACE4_APPEND_DATA is set but ACE4_WRITE_DATA is not (or vice versa), the server should either turn off ACE4_APPEND_DATA or reject the request with NFS4ERR_ATTRNOTSUPP.

サーバーが正確に実装できないSETATTR要求を受信した場合は、以前に説明されているEXECUTEおよびREADの場合を除いて、より制限されたアクセスの方向にERRを実行してください。たとえば、前の段落で説明されているように、サーバーが新しいデータを追加するのを区別できないとします。ACE4_APPEND_DATAが設定されていますが、ACE4_WRITE_DATAが設定されていないACE ACEを送信する場合(またはその逆)、サーバーはACE4_APPEND_DATAをオフにするか、またはNFS4ERR_ATTRNOTSUPPで要求を拒否します。 ACE4_DELETE vs. ACE4_DELETE_CHILD ACE4_DELETE対ACE4_DELETE_CHILD

Two access mask bits govern the ability to delete a directory entry: ACE4_DELETE on the object itself (the "target") and ACE4_DELETE_CHILD on the containing directory (the "parent").

2つのアクセスマスクBITSは、オブジェクト自体のACE4_DELETE( "ターゲット")およびinconsedディレクトリのACE4_DELETE_CHILD(「親」)を統括します。

Many systems also take the "sticky bit" (MODE4_SVTX) on a directory to allow unlink only to a user that owns either the target or the parent; on some such systems the decision also depends on whether the target is writable.


Servers SHOULD allow unlink if either ACE4_DELETE is permitted on the target, or ACE4_DELETE_CHILD is permitted on the parent. (Note that this is true even if the parent or target explicitly denies one of these permissions.)


If the ACLs in question neither explicitly ALLOW nor DENY either of the above, and if MODE4_SVTX is not set on the parent, then the server SHOULD allow the removal if and only if ACE4_ADD_FILE is permitted. In the case where MODE4_SVTX is set, the server may also require the remover to own either the parent or the target, or may require the target to be writable.


This allows servers to support something close to traditional UNIX-like semantics, with ACE4_ADD_FILE taking the place of the write bit.

これにより、サーバーは伝統的なUnix様のセマンティクスに近いものをサポートし、ACE4_ADD_FILEが書き込みビットの場所を取得します。 ACE flag エースの国旗

The bitmask constants used for the flag field are as follows:


   const ACE4_FILE_INHERIT_ACE             = 0x00000001;
   const ACE4_DIRECTORY_INHERIT_ACE        = 0x00000002;
   const ACE4_NO_PROPAGATE_INHERIT_ACE     = 0x00000004;
   const ACE4_INHERIT_ONLY_ACE             = 0x00000008;
   const ACE4_SUCCESSFUL_ACCESS_ACE_FLAG   = 0x00000010;
   const ACE4_FAILED_ACCESS_ACE_FLAG       = 0x00000020;
   const ACE4_IDENTIFIER_GROUP             = 0x00000040;
   const ACE4_INHERITED_ACE                = 0x00000080;

A server need not support any of these flags. If the server supports flags that are similar to, but not exactly the same as, these flags, the implementation may define a mapping between the protocol-defined flags and the implementation-defined flags.


For example, suppose a client tries to set an ACE with ACE4_FILE_INHERIT_ACE set but not ACE4_DIRECTORY_INHERIT_ACE. If the server does not support any form of ACL inheritance, the server should reject the request with NFS4ERR_ATTRNOTSUPP. If the server supports a single "inherit ACE" flag that applies to both files and directories, the server may reject the request (i.e., requiring the client to set both the file and directory inheritance flags). The server may also accept the request and silently turn on the ACE4_DIRECTORY_INHERIT_ACE flag.

たとえば、クライアントがACE4_FILE_INHERIT_ACEセットを使用してACEを設定しようとするが、ACE4_DIRECTORY_INHERIT_ACEを設定しようとしているとします。サーバーがACL継承の形式をサポートしていない場合、サーバーはNFS4ERR_ATTRNOTSUPPを使用して要求を拒否する必要があります。サーバーがファイルとディレクトリの両方に適用される単一の「継承ACE」フラグをサポートしている場合、サーバーは要求を拒否します(すなわち、クライアントにファイルとディレクトリの両方の継承フラグを設定する必要がある)。サーバーはまた要求を受け入れ、ace4_directory_inherit_aceフラグを静止している可能性があります。 Discussion of Flag Bits 旗ビットの議論

ACE4_FILE_INHERIT_ACE Any non-directory file in any sub-directory will get this ACE inherited.


ACE4_DIRECTORY_INHERIT_ACE Can be placed on a directory and indicates that this ACE should be added to each new directory created.


If this flag is set in an ACE in an ACL attribute to be set on a non-directory file system object, the operation attempting to set the ACL SHOULD fail with NFS4ERR_ATTRNOTSUPP.


ACE4_NO_PROPAGATE_INHERIT_ACE Can be placed on a directory. This flag tells the server that inheritance of this ACE should stop at newly created child directories.


ACE4_INHERIT_ONLY_ACE Can be placed on a directory but does not apply to the directory; ALLOW and DENY ACEs with this bit set do not affect access to the directory, and AUDIT and ALARM ACEs with this bit set do not trigger log or alarm events. Such ACEs only take effect once they are applied (with this bit cleared) to newly created files and directories as specified by the ACE4_FILE_INHERIT_ACE and ACE4_DIRECTORY_INHERIT_ACE flags.


If this flag is present on an ACE, but neither ACE4_DIRECTORY_INHERIT_ACE nor ACE4_FILE_INHERIT_ACE is present, then an operation attempting to set such an attribute SHOULD fail with NFS4ERR_ATTRNOTSUPP.


ACE4_SUCCESSFUL_ACCESS_ACE_FLAG and ACE4_FAILED_ACCESS_ACE_FLAG The ACE4_SUCCESSFUL_ACCESS_ACE_FLAG (SUCCESS) and ACE4_FAILED_ACCESS_ACE_FLAG (FAILED) flag bits may be set only on ACE4_SYSTEM_AUDIT_ACE_TYPE (AUDIT) and ACE4_SYSTEM_ALARM_ACE_TYPE (ALARM) ACE types. If during the processing of the file's ACL, the server encounters an AUDIT or ALARM ACE that matches the principal attempting the OPEN, the server notes that fact, and the presence, if any, of the SUCCESS and FAILED flags encountered in the AUDIT or ALARM ACE. Once the server completes the ACL processing, it then notes if the operation succeeded or failed. If the operation succeeded, and if the SUCCESS flag was set for a matching AUDIT or ALARM ACE, then the appropriate AUDIT or ALARM event occurs. If the operation failed, and if the FAILED flag was set for the matching AUDIT or ALARM ACE, then the appropriate AUDIT or ALARM event occurs. Either or both of the SUCCESS or FAILED can be set, but if neither is set, the AUDIT or ALARM ACE is not useful.

ACE4_SUCCESSFUR_ACCESS_ACE_FLAGとACE4_FAILED_ACCESS_ACE_FLAG ACE4_SUCCESSFUL_ACCESS_ACES_FLAG(成功)とACE4_FAILED_ACCESS_ACE_FLAG(故障)フラグビットは、ACE4_SYSTEM_AUDIT_ACE_AACE_TYPE(監査)およびACE4_SYSTEM_ALARM_ACE_TYPE(ALARM)ACEタイプでのみ設定できます。ファイルのACLの処理中に、サーバーは、オープンを試みるプリンシパルと一致する監査またはアラームACEに遭遇し、その事実、および監査またはアラームで発生した成功と失敗のフラグの有無を示します。エース。サーバーがACL処理を完了すると、操作が成功または失敗した場合は注意してください。操作が成功した場合、一致する監査またはアラームACEに成功フラグが設定されている場合は、適切な監査またはアラームイベントが発生します。操作に失敗した場合、および障害のあるフラグが一致する監査またはアラームACEに設定された場合、適切な監査またはアラームイベントが発生します。成功または失敗のどちらかまたは両方を設定することができますが、どちらに設定されていない場合、監査またはアラームACEは役に立ちません。

The previously described processing applies to ACCESS operations even when they return NFS4_OK. For the purposes of AUDIT and ALARM, we consider an ACCESS operation to be a "failure" if it fails to return a bit that was requested and supported.


ACE4_IDENTIFIER_GROUP Indicates that the "who" refers to a GROUP as defined under UNIX or a GROUP ACCOUNT as defined under Windows. Clients and servers MUST ignore the ACE4_IDENTIFIER_GROUP flag on ACEs with a who value equal to one of the special identifiers outlined in Section

ACE4_IDENTIFIER_GROUP Windowsで定義されているUNIXまたはグループアカウントで定義されているグループを「Who」と参照することを示します。クライアントとサーバーは、ACEのACE4_IDENTIFIER_GROUPフラグを6.2.1.5項で概説されている特殊識別子の1つに等しい値を指定して、ACES上のACE4_IDENTIFIER_GROUPフラグを無視する必要があります。

ACE4_INHERITED_ACE Indicates that this ACE is inherited from a parent directory. A server that supports automatic inheritance will place this flag on any ACEs inherited from the parent directory when creating a new object. Client applications will use this to perform automatic inheritance. Clients and servers MUST clear this bit in the acl attribute; it may only be used in the dacl and sacl attributes.

ACE4_INHERTITED_ACEこのACEが親ディレクトリから継承されていることを示します。自動継承をサポートするサーバーは、新しいオブジェクトを作成するときに、親ディレクトリから継承されたACEにこのフラグを配置します。クライアントアプリケーションはこれを使用して自動継承を実行します。クライアントとサーバーはACL属性でこのビットをクリアする必要があります。DACL属性とSACLの属性でのみ使用できます。 ACE Who エースだ

The "who" field of an ACE is an identifier that specifies the principal or principals to whom the ACE applies. It may refer to a user or a group, with the flag bit ACE4_IDENTIFIER_GROUP specifying which.


There are several special identifiers that need to be understood universally, rather than in the context of a particular DNS domain. Some of these identifiers cannot be understood when an NFS client accesses the server, but have meaning when a local process accesses the file. The ability to display and modify these permissions is permitted over NFS, even if none of the access methods on the server understands the identifiers.


   | Who           | Description                                      |
   | OWNER         | The owner of the file.                           |
   | GROUP         | The group associated with the file.              |
   | EVERYONE      | The world, including the owner and owning group. |
   | INTERACTIVE   | Accessed from an interactive terminal.           |
   | NETWORK       | Accessed via the network.                        |
   | DIALUP        | Accessed as a dialup user to the server.         |
   | BATCH         | Accessed from a batch job.                       |
   | ANONYMOUS     | Accessed without any authentication.             |
   | AUTHENTICATED | Any authenticated user (opposite of ANONYMOUS).  |
   | SERVICE       | Access from a system service.                    |

Table 7


To avoid conflict, these special identifiers are distinguished by an appended "@" and should appear in the form "xxxx@" (with no domain name after the "@"), for example, ANONYMOUS@.

競合を回避するために、これらの特別な識別子は追加された "@"によって区別され、 "xxxx @"の形式( "@"の後にドメイン名がない)に表示されるべきです(例えば、anonymous @)。

The ACE4_IDENTIFIER_GROUP flag MUST be ignored on entries with these special identifiers. When encoding entries with these special identifiers, the ACE4_IDENTIFIER_GROUP flag SHOULD be set to zero.

ACE4_IDENTIFIER_GROUPフラグは、これらの特別な識別子を持つエントリでは無視されなければなりません。これらの特別な識別子を使用してエントリを符号化するときは、ace4_identifier_groupフラグをゼロに設定する必要があります。 Discussion of EVERYONE@ 皆の議論@

It is important to note that "EVERYONE@" is not equivalent to the UNIX "other" entity. This is because, by definition, UNIX "other" does not include the owner or owning group of a file. "EVERYONE@" means literally everyone, including the owner or owning group.


6.2.2. Attribute 58: dacl
6.2.2. 属性58:DACL.

The dacl attribute is like the acl attribute, but dacl allows just ALLOW and DENY ACEs. The dacl attribute supports automatic inheritance (see Section


6.2.3. Attribute 59: sacl
6.2.3. 属性59:SACL.

The sacl attribute is like the acl attribute, but sacl allows just AUDIT and ALARM ACEs. The sacl attribute supports automatic inheritance (see Section


6.2.4. Attribute 33: mode
6.2.4. 属性33:モード

The NFSv4.1 mode attribute is based on the UNIX mode bits. The following bits are defined:


   const MODE4_SUID = 0x800;  /* set user id on execution */
   const MODE4_SGID = 0x400;  /* set group id on execution */
   const MODE4_SVTX = 0x200;  /* save text even after use */
   const MODE4_RUSR = 0x100;  /* read permission: owner */
   const MODE4_WUSR = 0x080;  /* write permission: owner */
   const MODE4_XUSR = 0x040;  /* execute permission: owner */
   const MODE4_RGRP = 0x020;  /* read permission: group */
   const MODE4_WGRP = 0x010;  /* write permission: group */
   const MODE4_XGRP = 0x008;  /* execute permission: group */
   const MODE4_ROTH = 0x004;  /* read permission: other */
   const MODE4_WOTH = 0x002;  /* write permission: other */
   const MODE4_XOTH = 0x001;  /* execute permission: other */

Bits MODE4_RUSR, MODE4_WUSR, and MODE4_XUSR apply to the principal identified in the owner attribute. Bits MODE4_RGRP, MODE4_WGRP, and MODE4_XGRP apply to principals identified in the owner_group attribute but who are not identified in the owner attribute. Bits MODE4_ROTH, MODE4_WOTH, and MODE4_XOTH apply to any principal that does not match that in the owner attribute and does not have a group matching that of the owner_group attribute.

BITS MODE4_RUSR、MODE4_WUSR、およびMODE4_XUSRは、所有者属性で識別されているプリンシパルに適用されます。BITS MODE4_RGRP、MODE4_WGRP、およびMODE4_XGRPは、owner_group属性で識別されたプリンシパルに適用されますが、所有者属性では識別されません。BITS MODE4_ROTH、MODE4_WOTH、およびMODE4_XOTSは、所有者属性のそれと一致しないプリンシパルに適用され、owner_group属性のグループが一致するグループがありません。

Bits within a mode other than those specified above are not defined by this protocol. A server MUST NOT return bits other than those defined above in a GETATTR or READDIR operation, and it MUST return NFS4ERR_INVAL if bits other than those defined above are set in a SETATTR, CREATE, OPEN, VERIFY, or NVERIFY operation.


6.2.5. Attribute 74: mode_set_masked
6.2.5. 属性74:mode_set_masked

The mode_set_masked attribute is a write-only attribute that allows individual bits in the mode attribute to be set or reset, without changing others. It allows, for example, the bits MODE4_SUID, MODE4_SGID, and MODE4_SVTX to be modified while leaving unmodified any of the nine low-order mode bits devoted to permissions.


In such instances that the nine low-order bits are left unmodified, then neither the acl nor the dacl attribute should be automatically modified as discussed in Section 6.4.1.


The mode_set_masked attribute consists of two words, each in the form of a mode4. The first consists of the value to be applied to the current mode value and the second is a mask. Only bits set to one in the mask word are changed (set or reset) in the file's mode. All other bits in the mode remain unchanged. Bits in the first word that correspond to bits that are zero in the mask are ignored, except that undefined bits are checked for validity and can result in NFS4ERR_INVAL as described below.


The mode_set_masked attribute is only valid in a SETATTR operation. If it is used in a CREATE or OPEN operation, the server MUST return NFS4ERR_INVAL.


Bits not defined as valid in the mode attribute are not valid in either word of the mode_set_masked attribute. The server MUST return NFS4ERR_INVAL if any such bits are set to one in a SETATTR. If the mode and mode_set_masked attributes are both specified in the same SETATTR, the server MUST also return NFS4ERR_INVAL.


6.3. Common Methods
6.3. 一般的な方法

The requirements in this section will be referred to in future sections, especially Section 6.4.


6.3.1. Interpreting an ACL
6.3.1. ACLの解釈 Server Considerations サーバーの考慮事項

The server uses the algorithm described in Section 6.2.1 to determine whether an ACL allows access to an object. However, the ACL might not be the sole determiner of access. For example:


* In the case of a file system exported as read-only, the server may deny write access even though an object's ACL grants it.

* 読み取り専用としてエクスポートされたファイルシステムの場合、オブジェクトのACLがそれを許可していてもサーバは書き込みアクセスを拒否することがあります。

* Server implementations MAY grant ACE4_WRITE_ACL and ACE4_READ_ACL permissions to prevent a situation from arising in which there is no valid way to ever modify the ACL.

* サーバー実装は、ACLを変更するための有効な方法がないという状況が発生しないことを防ぐために、ACE4_WRITE_ACLおよびACE4_READ_ACL権限を付与することができます。

* All servers will allow a user the ability to read the data of the file when only the execute permission is granted (i.e., if the ACL denies the user the ACE4_READ_DATA access and allows the user ACE4_EXECUTE, the server will allow the user to read the data of the file).

* すべてのサーバーは、実行権限のみが許可されたときに(つまり、ACLがACLがユーザーを拒否し、ユーザーACE4_EXECUTEを許可する場合、ユーザーがユーザーがユーザーがユーザーがユーザーが読み取ることを許可することをユーザーに読み取ることができます。ファイルの)

* Many servers have the notion of owner-override in which the owner of the object is allowed to override accesses that are denied by the ACL. This may be helpful, for example, to allow users continued access to open files on which the permissions have changed.

* 多くのサーバーは、オブジェクトの所有者がACLによって拒否されたアクセスをオーバーライドすることを許可されている所有者のオーバーライドの概念を持っています。たとえば、ユーザーがアクセス許可が変更されたオープンファイルへのアクセスを継続できるようにするために役立ちます。

* Many servers have the notion of a "superuser" that has privileges beyond an ordinary user. The superuser may be able to read or write data or metadata in ways that would not be permitted by the ACL.

* 多くのサーバーは、通常のユーザーを超えた特権を持つ「スーパーユーザー」の概念を持っています。スーパーユーザーは、ACLによって許可されない方法でデータまたはメタデータを読み書きすることができます。

* A retention attribute might also block access otherwise allowed by ACLs (see Section 5.13).

* 保持属性は、ACLによってそうでなければ許可されているアクセスをブロックすることもあります(セクション5.13を参照)。 Client Considerations クライアントの考慮事項

Clients SHOULD NOT do their own access checks based on their interpretation of the ACL, but rather use the OPEN and ACCESS operations to do access checks. This allows the client to act on the results of having the server determine whether or not access should be granted based on its interpretation of the ACL.


Clients must be aware of situations in which an object's ACL will define a certain access even though the server will not enforce it. In general, but especially in these situations, the client needs to do its part in the enforcement of access as defined by the ACL. To do this, the client MAY send the appropriate ACCESS operation prior to servicing the request of the user or application in order to determine whether the user or application should be granted the access requested. For examples in which the ACL may define accesses that the server doesn't enforce, see Section


6.3.2. Computing a Mode Attribute from an ACL
6.3.2. ACLからMODE属性を計算します

The following method can be used to calculate the MODE4_R*, MODE4_W*, and MODE4_X* bits of a mode attribute, based upon an ACL.

次の方法を使用して、ACLに基づいてMODE4_R *、MODE4_W *、およびMODE属性のMODE4_X *ビットを計算することができます。

First, for each of the special identifiers OWNER@, GROUP@, and EVERYONE@, evaluate the ACL in order, considering only ALLOW and DENY ACEs for the identifier EVERYONE@ and for the identifier under consideration. The result of the evaluation will be an NFSv4 ACL mask showing exactly which bits are permitted to that identifier.

まず、特別な識別子の所有者@、Group @、およびhveryn @のそれぞれについて、ACLを順番に評価し、識別子@および検討中の識別子の識別子のACEを許可および拒否します。評価結果は、どのビットがその識別子に許可されているかを正確に示すNFSV4 ACLマスクになります。

Then translate the calculated mask for OWNER@, GROUP@, and EVERYONE@ into mode bits for, respectively, the user, group, and other, as follows:

次に、計算されたマスクを所有者@、Group @、およびhomeing @に、それぞれユーザー、グループ、その他のモードビットに変換します。

1. Set the read bit (MODE4_RUSR, MODE4_RGRP, or MODE4_ROTH) if and only if ACE4_READ_DATA is set in the corresponding mask.

1. ace4_read_dataが対応するマスクに設定されている場合に限り、読み取りビット(MODE4_RUSR、MODE4_RGRP、またはMODE4_ROTH)を設定します。

2. Set the write bit (MODE4_WUSR, MODE4_WGRP, or MODE4_WOTH) if and only if ACE4_WRITE_DATA and ACE4_APPEND_DATA are both set in the corresponding mask.

2. ACE4_WRITE_DATAとACE4_APPEND_DATAが両方とも対応するマスクに設定されている場合に限り、書き込みビット(MODE4_WUSR、MODE4_WGRP、またはMODE4_WOTH)を設定します。

3. Set the execute bit (MODE4_XUSR, MODE4_XGRP, or MODE4_XOTH), if and only if ACE4_EXECUTE is set in the corresponding mask.

3. 対応するマスクにace4_executeが設定されている場合に限り、EXECUTEビット(MODE4_XUSR、MODE4_XGRP、またはMODE4_XOTH)を設定します。 Discussion 考察

Some server implementations also add bits permitted to named users and groups to the group bits (MODE4_RGRP, MODE4_WGRP, and MODE4_XGRP).


Implementations are discouraged from doing this, because it has been found to cause confusion for users who see members of a file's group denied access that the mode bits appear to allow. (The presence of DENY ACEs may also lead to such behavior, but DENY ACEs are expected to be more rarely used.)


The same user confusion seen when fetching the mode also results if setting the mode does not effectively control permissions for the owner, group, and other users; this motivates some of the requirements that follow.


6.4. Requirements
6.4. 要件

The server that supports both mode and ACL must take care to synchronize the MODE4_*USR, MODE4_*GRP, and MODE4_*OTH bits with the ACEs that have respective who fields of "OWNER@", "GROUP@", and "EVERYONE@". This way, the client can see if semantically equivalent access permissions exist whether the client asks for the owner, owner_group, and mode attributes or for just the ACL.

モードとACLの両方をサポートするサーバーは、MODE4_ * USR、MODE4_ * GRP、およびMODE4_ * OTSビットを「所有者@」、「GROUP @」、および「皆さん@」の項目を持つACESと認識する必要があります。"。このようにして、クライアントは、クライアントが所有者、owner_group、およびモードの属性を要求するか、またはACLだけであるかどうかを意味的に同等のアクセス許可が存在するかどうかを確認できます。

In this section, much is made of the methods in Section 6.3.2. Many requirements refer to this section. But note that the methods have behaviors specified with "SHOULD". This is intentional, to avoid invalidating existing implementations that compute the mode according to the withdrawn POSIX ACL draft (1003.1e draft 17), rather than by actual permissions on owner, group, and other.


6.4.1. Setting the Mode and/or ACL Attributes
6.4.1. モードおよび/またはACL属性を設定する

In the case where a server supports the sacl or dacl attribute, in addition to the acl attribute, the server MUST fail a request to set the acl attribute simultaneously with a dacl or sacl attribute. The error to be given is NFS4ERR_ATTRNOTSUPP.

サーバーがSACLまたはDACL属性をサポートしている場合は、ACL属性に加えて、サーバーはDACLまたはSACL属性と同時にACL属性を設定する要求に失敗する必要があります。与えられるエラーはNFS4ERR_ATTRNOTSUPPです。 Setting Mode and not ACL 設定モードとACLではなく

When any of the nine low-order mode bits are subject to change, either because the mode attribute was set or because the mode_set_masked attribute was set and the mask included one or more bits from the nine low-order mode bits, and no ACL attribute is explicitly set, the acl and dacl attributes must be modified in accordance with the updated value of those bits. This must happen even if the value of the low-order bits is the same after the mode is set as before.


Note that any AUDIT or ALARM ACEs (hence any ACEs in the sacl attribute) are unaffected by changes to the mode.


In cases in which the permissions bits are subject to change, the acl and dacl attributes MUST be modified such that the mode computed via the method in Section 6.3.2 yields the low-order nine bits (MODE4_R*, MODE4_W*, MODE4_X*) of the mode attribute as modified by the attribute change. The ACL attributes SHOULD also be modified such that:

アクセス許可ビットが変更される場合は、6.3.2項のメソッドを介して計算されたモードが下位9ビット(MODE4_R *、MODE4_W *、MODE4_X *)をもたらすようにACLおよびDACL属性を変更する必要があります。属性変更によって変更されたモード属性の。ACL属性も変更する必要があります。

1. If MODE4_RGRP is not set, entities explicitly listed in the ACL other than OWNER@ and EVERYONE@ SHOULD NOT be granted ACE4_READ_DATA.

1. MODE4_RGRPが設定されていない場合は、所有者@とholider @以外のACLに明示的にリストされているエンティティは、ACE4_READ_DATAを付与しないでください。

2. If MODE4_WGRP is not set, entities explicitly listed in the ACL other than OWNER@ and EVERYONE@ SHOULD NOT be granted ACE4_WRITE_DATA or ACE4_APPEND_DATA.

2. MODE4_WGRPが設定されていない場合は、所有者@およびhomeone @以外のACLに明示的にリストされているエンティティは、ACE4_WRITE_DATAまたはACE4_APPEND_DATAを付与しないでください。

3. If MODE4_XGRP is not set, entities explicitly listed in the ACL other than OWNER@ and EVERYONE@ SHOULD NOT be granted ACE4_EXECUTE.

3. MODE4_XGRPが設定されていない場合は、所有者@およびhervery @以外のACLに明示的にリストされているエンティティがACE4_EXECUTEを付与しないでください。

Access mask bits other than those listed above, appearing in ALLOW ACEs, MAY also be disabled.


Note that ACEs with the flag ACE4_INHERIT_ONLY_ACE set do not affect the permissions of the ACL itself, nor do ACEs of the type AUDIT and ALARM. As such, it is desirable to leave these ACEs unmodified when modifying the ACL attributes.

フラグACE4_INHERIT_ONLY_ACE SETを持つACEは、ACL自体のアクセス許可には影響しません。また、タイプ監査とアラームのACEを実行しません。そのため、ACL属性を変更するときにこれらのACEを変更しなくなることが望ましいです。

Also note that the requirement may be met by discarding the acl and dacl, in favor of an ACL that represents the mode and only the mode. This is permitted, but it is preferable for a server to preserve as much of the ACL as possible without violating the above requirements. Discarding the ACL makes it effectively impossible for a file created with a mode attribute to inherit an ACL (see Section 6.4.3).

また、モードとモードのみを表すACLを支持して、ACLとDACLを廃棄することで、要件を満たすことができることにも注意してください。これは許可されていますが、サーバーが上記の要件に違反することなくできるだけ多くのACLを保存することが好ましいです。ACLを破棄すると、MODE属性を使用して作成されたファイルがACLを継承するのに効果的に不可能です(セクション6.4.3を参照)。 Setting ACL and Not Mode ACLを設定してモードではありません

When setting the acl or dacl and not setting the mode or mode_set_masked attributes, the permission bits of the mode need to be derived from the ACL. In this case, the ACL attribute SHOULD be set as given. The nine low-order bits of the mode attribute (MODE4_R*, MODE4_W*, MODE4_X*) MUST be modified to match the result of the method in Section 6.3.2. The three high-order bits of the mode (MODE4_SUID, MODE4_SGID, MODE4_SVTX) SHOULD remain unchanged.

ACLまたはDACLを設定し、モードまたはMODE_SET_MASKED属性を設定しない場合、モードの許可ビットはACLから派生する必要があります。この場合、ACL属性は指定されているとおりに設定する必要があります。MODE属性の9つの下位ビット(MODE4_R *、MODE4_W *、MODE4_X *)は、6.3.2のメソッドの結果と一致するように変更する必要があります。モードの3つの上位ビット(MODE4_SUID、MODE4_SGID、MODE4_SVTX)は変更されていないはずです。 Setting Both ACL and Mode ACLとモードの両方を設定します

When setting both the mode (includes use of either the mode attribute or the mode_set_masked attribute) and the acl or dacl attributes in the same operation, the attributes MUST be applied in this order: mode (or mode_set_masked), then ACL. The mode-related attribute is set as given, then the ACL attribute is set as given, possibly changing the final mode, as described above in Section


6.4.2. Retrieving the Mode and/or ACL Attributes
6.4.2. モードおよび/またはACL属性を取得する

This section applies only to servers that support both the mode and ACL attributes.


Some server implementations may have a concept of "objects without ACLs", meaning that all permissions are granted and denied according to the mode attribute and that no ACL attribute is stored for that object. If an ACL attribute is requested of such a server, the server SHOULD return an ACL that does not conflict with the mode; that is to say, the ACL returned SHOULD represent the nine low-order bits of the mode attribute (MODE4_R*, MODE4_W*, MODE4_X*) as described in Section 6.3.2.

一部のサーバー実装では、「ACLのないオブジェクト」の概念がある場合があります。つまり、モード属性に従ってすべての権限が付与され、そのオブジェクトにACL属性が保存されていないことを意味します。そのようなサーバーにACL属性が要求された場合、サーバーはモードと競合しないACLを返す必要があります。つまり、返されるACLは、6.3.2項で説明されているように、モード属性の9つの下位ビット(MODE4_R *、MODE4_W *、MODE4_X *)を表す必要があります。

For other server implementations, the ACL attribute is always present for every object. Such servers SHOULD store at least the three high-order bits of the mode attribute (MODE4_SUID, MODE4_SGID, MODE4_SVTX). The server SHOULD return a mode attribute if one is requested, and the low-order nine bits of the mode (MODE4_R*, MODE4_W*, MODE4_X*) MUST match the result of applying the method in Section 6.3.2 to the ACL attribute.

他のサーバー実装では、ACL属性はすべてのオブジェクトに対して常に存在します。そのようなサーバーは、モード属性の少なくとも3次ビット(MODE4_SUID、MODE4_SGID、MODE4_SVTX)を保存する必要があります。サーバーが要求された場合はモード属性を返し、モードの下位9ビット(MODE4_R *、MODE4_W *、MODE4_X *)が、6.3.2項のメソッドをACL属性に適用した結果と一致する必要があります。

6.4.3. Creating New Objects
6.4.3. 新しいオブジェクトを作成する

If a server supports any ACL attributes, it may use the ACL attributes on the parent directory to compute an initial ACL attribute for a newly created object. This will be referred to as the inherited ACL within this section. The act of adding one or more ACEs to the inherited ACL that are based upon ACEs in the parent directory's ACL will be referred to as inheriting an ACE within this section.


Implementors should standardize what the behavior of CREATE and OPEN must be depending on the presence or absence of the mode and ACL attributes.

実装者は、MODE属性とACL属性の有無に応じて、CREATE AND OPENの動作が何であるかを標準化する必要があります。

1. If just the mode is given in the call:

1. モードだけが呼び出しで指定されている場合

In this case, inheritance SHOULD take place, but the mode MUST be applied to the inherited ACL as described in Section, thereby modifying the ACL.


2. If just the ACL is given in the call:

2. ACLが呼び出しに与えられたら:

In this case, inheritance SHOULD NOT take place, and the ACL as defined in the CREATE or OPEN will be set without modification, and the mode modified as in Section


3. If both mode and ACL are given in the call:

3. コールにモードとACLの両方が指定されている場合

In this case, inheritance SHOULD NOT take place, and both attributes will be set as described in Section


4. If neither mode nor ACL is given in the call:

4. どちらのモードもACLも呼び出しで指定されていない場合

In the case where an object is being created without any initial attributes at all, e.g., an OPEN operation with an opentype4 of OPEN4_CREATE and a createmode4 of EXCLUSIVE4, inheritance SHOULD NOT take place (note that EXCLUSIVE4_1 is a better choice of createmode4, since it does permit initial attributes). Instead, the server SHOULD set permissions to deny all access to the newly created object. It is expected that the appropriate client will set the desired attributes in a subsequent SETATTR operation, and the server SHOULD allow that operation to succeed, regardless of what permissions the object is created with. For example, an empty ACL denies all permissions, but the server should allow the owner's SETATTR to succeed even though WRITE_ACL is implicitly denied.


In other cases, inheritance SHOULD take place, and no modifications to the ACL will happen. The mode attribute, if supported, MUST be as computed in Section 6.3.2, with the MODE4_SUID, MODE4_SGID, and MODE4_SVTX bits clear. If no inheritable ACEs exist on the parent directory, the rules for creating acl, dacl, or sacl attributes are implementation defined. If either the dacl or sacl attribute is supported, then the ACL4_DEFAULTED flag SHOULD be set on the newly created attributes.

それ以外の場合は、継承が行われるべきであり、ACLへの変更は起こらないであろう。MODE属性は、サポートされている場合は、MODE4_SUID、MODE4_SGID、およびMODE4_SVTXビットがクリアされた状態で、セクション6.3.2で計算されている必要があります。親ディレクトリに継承可能なACEが存在しない場合は、ACL、DACL、またはSACL属性を作成するための規則が定義されています。DACLまたはSACL属性がサポートされている場合は、新しく作成された属性にACL4_Defaultedフラグを設定する必要があります。 The Inherited ACL 継承されたACL

If the object being created is not a directory, the inherited ACL SHOULD NOT inherit ACEs from the parent directory ACL unless the ACE4_FILE_INHERIT_FLAG is set.


If the object being created is a directory, the inherited ACL should inherit all inheritable ACEs from the parent directory, that is, those that have the ACE4_FILE_INHERIT_ACE or ACE4_DIRECTORY_INHERIT_ACE flag set. If the inheritable ACE has ACE4_FILE_INHERIT_ACE set but ACE4_DIRECTORY_INHERIT_ACE is clear, the inherited ACE on the newly created directory MUST have the ACE4_INHERIT_ONLY_ACE flag set to prevent the directory from being affected by ACEs meant for non-directories.


When a new directory is created, the server MAY split any inherited ACE that is both inheritable and effective (in other words, that has neither ACE4_INHERIT_ONLY_ACE nor ACE4_NO_PROPAGATE_INHERIT_ACE set), into two ACEs, one with no inheritance flags and one with ACE4_INHERIT_ONLY_ACE set. (In the case of a dacl or sacl attribute, both of those ACEs SHOULD also have the ACE4_INHERITED_ACE flag set.) This makes it simpler to modify the effective permissions on the directory without modifying the ACE that is to be inherited to the new directory's children.

新しいディレクトリが作成されると、サーバーは、継承可能かつ効果的な継承されたACE(つまり、ACE4_INHERIT_ONLY_ACEもACE4_NO_PROPAGAT_INHERIT_ACEセットも持ちません)、継承フラグを持たない2つのACE、およびACE4_INHERIT_ONLY_ACEセットを持つものではない。(DACLまたはSACL属性の場合、これらのACEの両方にACE4_INHERTITED_ACEフラグが設定されている必要があります。)これにより、新しいディレクトリの子供に継承されるACEを変更せずにディレクトリに対する効果的な権限を変更することができます。。 Automatic Inheritance 自動継承

The acl attribute consists only of an array of ACEs, but the sacl (Section 6.2.3) and dacl (Section 6.2.2) attributes also include an additional flag field.


   struct nfsacl41 {
           aclflag4        na41_flag;
           nfsace4         na41_aces<>;

The flag field applies to the entire sacl or dacl; three flag values are defined:


   const ACL4_AUTO_INHERIT         = 0x00000001;
   const ACL4_PROTECTED            = 0x00000002;
   const ACL4_DEFAULTED            = 0x00000004;

and all other bits must be cleared. The ACE4_INHERITED_ACE flag may be set in the ACEs of the sacl or dacl (whereas it must always be cleared in the acl).


Together these features allow a server to support automatic inheritance, which we now explain in more detail.


Inheritable ACEs are normally inherited by child objects only at the time that the child objects are created; later modifications to inheritable ACEs do not result in modifications to inherited ACEs on descendants.


However, the dacl and sacl provide an OPTIONAL mechanism that allows a client application to propagate changes to inheritable ACEs to an entire directory hierarchy.


A server that supports this performs inheritance at object creation time in the normal way, and SHOULD set the ACE4_INHERITED_ACE flag on any inherited ACEs as they are added to the new object.


A client application such as an ACL editor may then propagate changes to inheritable ACEs on a directory by recursively traversing that directory's descendants and modifying each ACL encountered to remove any ACEs with the ACE4_INHERITED_ACE flag and to replace them by the new inheritable ACEs (also with the ACE4_INHERITED_ACE flag set). It uses the existing ACE inheritance flags in the obvious way to decide which ACEs to propagate. (Note that it may encounter further inheritable ACEs when descending the directory hierarchy and that those will also need to be taken into account when propagating inheritable ACEs to further descendants.)


The reach of this propagation may be limited in two ways: first, automatic inheritance is not performed from any directory ACL that has the ACL4_AUTO_INHERIT flag cleared; and second, automatic inheritance stops wherever an ACL with the ACL4_PROTECTED flag is set, preventing modification of that ACL and also (if the ACL is set on a directory) of the ACL on any of the object's descendants.


This propagation is performed independently for the sacl and the dacl attributes; thus, the ACL4_AUTO_INHERIT and ACL4_PROTECTED flags may be independently set for the sacl and the dacl, and propagation of one type of acl may continue down a hierarchy even where propagation of the other acl has stopped.


New objects should be created with a dacl and a sacl that both have the ACL4_PROTECTED flag cleared and the ACL4_AUTO_INHERIT flag set to the same value as that on, respectively, the sacl or dacl of the parent object.


Both the dacl and sacl attributes are RECOMMENDED, and a server may support one without supporting the other.


A server that supports both the old acl attribute and one or both of the new dacl or sacl attributes must do so in such a way as to keep all three attributes consistent with each other. Thus, the ACEs reported in the acl attribute should be the union of the ACEs reported in the dacl and sacl attributes, except that the ACE4_INHERITED_ACE flag must be cleared from the ACEs in the acl. And of course a client that queries only the acl will be unable to determine the values of the sacl or dacl flag fields.


When a client performs a SETATTR for the acl attribute, the server SHOULD set the ACL4_PROTECTED flag to true on both the sacl and the dacl. By using the acl attribute, as opposed to the dacl or sacl attributes, the client signals that it may not understand automatic inheritance, and thus cannot be trusted to set an ACL for which automatic inheritance would make sense.


When a client application queries an ACL, modifies it, and sets it again, it should leave any ACEs marked with ACE4_INHERITED_ACE unchanged, in their original order, at the end of the ACL. If the application is unable to do this, it should set the ACL4_PROTECTED flag. This behavior is not enforced by servers, but violations of this rule may lead to unexpected results when applications perform automatic inheritance.


If a server also supports the mode attribute, it SHOULD set the mode in such a way that leaves inherited ACEs unchanged, in their original order, at the end of the ACL. If it is unable to do so, it SHOULD set the ACL4_PROTECTED flag on the file's dacl.


Finally, in the case where the request that creates a new file or directory does not also set permissions for that file or directory, and there are also no ACEs to inherit from the parent's directory, then the server's choice of ACL for the new object is implementation-dependent. In this case, the server SHOULD set the ACL4_DEFAULTED flag on the ACL it chooses for the new object. An application performing automatic inheritance takes the ACL4_DEFAULTED flag as a sign that the ACL should be completely replaced by one generated using the automatic inheritance rules.


7. Single-Server Namespace
7. シングルサーバーネームスペース

This section describes the NFSv4 single-server namespace. Single-server namespaces may be presented directly to clients, or they may be used as a basis to form larger multi-server namespaces (e.g., site-wide or organization-wide) to be presented to clients, as described in Section 11.

このセクションでは、NFSV4 Single-Serverネームスペースについて説明します。シングルサーバーネームスペースは、クライアントに直接表示されることも、セクション11で説明されているように、より大きなマルチサーバーネームスペース(例えば、サイト全体または組織全体)を形成するための基礎として使用されてもよい。

7.1. Server Exports
7.1. サーバーエクスポート

On a UNIX server, the namespace describes all the files reachable by pathnames under the root directory or "/". On a Windows server, the namespace constitutes all the files on disks named by mapped disk letters. NFS server administrators rarely make the entire server's file system namespace available to NFS clients. More often, portions of the namespace are made available via an "export" feature. In previous versions of the NFS protocol, the root filehandle for each export is obtained through the MOUNT protocol; the client sent a string that identified the export name within the namespace and the server returned the root filehandle for that export. The MOUNT protocol also provided an EXPORTS procedure that enumerated the server's exports.

UNIXサーバーでは、ネームスペースは、ルートディレクトリまたは "/"の下のパス名によって到達可能なすべてのファイルを記述します。Windows Serverでは、ネームスペースはマッピングされたディスク文字で指定されたディスク上のすべてのファイルを構成します。NFS Server管理者は、サーバーのファイルシステムの名前空間全体をNFSクライアントに使用できるようにしてください。より頻繁には、名前空間の一部は「エクスポート」機能を介して利用可能にされています。以前のバージョンのNFSプロトコルでは、各エクスポートのルートファイルハンドルがマウントプロトコルを介して取得されます。クライアントはネームスペース内でエクスポート名を識別した文字列を送信し、サーバーはそのエクスポートのルートファイルハンドルを返しました。マウントプロトコルは、サーバーのエクスポートを列挙したエクスポート手順も提供されていました。

7.2. Browsing Exports
7.2. 排出を閲覧する

The NFSv4.1 protocol provides a root filehandle that clients can use to obtain filehandles for the exports of a particular server, via a series of LOOKUP operations within a COMPOUND, to traverse a path. A common user experience is to use a graphical user interface (perhaps a file "Open" dialog window) to find a file via progressive browsing through a directory tree. The client must be able to move from one export to another export via single-component, progressive LOOKUP operations.


This style of browsing is not well supported by the NFSv3 protocol. In NFSv3, the client expects all LOOKUP operations to remain within a single server file system. For example, the device attribute will not change. This prevents a client from taking namespace paths that span exports.


In the case of NFSv3, an automounter on the client can obtain a snapshot of the server's namespace using the EXPORTS procedure of the MOUNT protocol. If it understands the server's pathname syntax, it can create an image of the server's namespace on the client. The parts of the namespace that are not exported by the server are filled in with directories that might be constructed similarly to an NFSv4.1 "pseudo file system" (see Section 7.3) that allows the user to browse from one mounted file system to another. There is a drawback to this representation of the server's namespace on the client: it is static. If the server administrator adds a new export, the client will be unaware of it.


7.3. Server Pseudo File System
7.3. サーバー疑似ファイルシステム

NFSv4.1 servers avoid this namespace inconsistency by presenting all the exports for a given server within the framework of a single namespace for that server. An NFSv4.1 client uses LOOKUP and READDIR operations to browse seamlessly from one export to another.


Where there are portions of the server namespace that are not exported, clients require some way of traversing those portions to reach actual exported file systems. A technique that servers may use to provide for this is to bridge the unexported portion of the namespace via a "pseudo file system" that provides a view of exported directories only. A pseudo file system has a unique fsid and behaves like a normal, read-only file system.


Based on the construction of the server's namespace, it is possible that multiple pseudo file systems may exist. For example,


           /a              pseudo file system
           /a/b            real file system
           /a/b/c          pseudo file system
           /a/b/c/d        real file system

Each of the pseudo file systems is considered a separate entity and therefore MUST have its own fsid, unique among all the fsids for that server.


7.4. Multiple Roots
7.4. 複数の根

Certain operating environments are sometimes described as having "multiple roots". In such environments, individual file systems are commonly represented by disk or volume names. NFSv4 servers for these platforms can construct a pseudo file system above these root names so that disk letters or volume names are simply directory names in the pseudo root.


7.5. Filehandle Volatility
7.5. FileHandleのボラティリティ

The nature of the server's pseudo file system is that it is a logical representation of file system(s) available from the server. Therefore, the pseudo file system is most likely constructed dynamically when the server is first instantiated. It is expected that the pseudo file system may not have an on-disk counterpart from which persistent filehandles could be constructed. Even though it is preferable that the server provide persistent filehandles for the pseudo file system, the NFS client should expect that pseudo file system filehandles are volatile. This ca