rfc2408.txt

著名的RFC文档,其中有一些文档是已经翻译成中文的的.

Network Working Group                                      D. Maughan
Request for Comments: 2408                   National Security Agency
Category: Standards Track                                M. Schertler
                                                       Securify, Inc.
                                                         M. Schneider
                                             National Security Agency
                                                            J. Turner
                                              RABA Technologies, Inc.
                                                        November 1998


   Internet Security Association and Key Management Protocol (ISAKMP)

Status of this Memo

   This document specifies an Internet standards track protocol for the
   Internet community, and requests discussion and suggestions for
   improvements.  Please refer to the current edition of the "Internet
   Official Protocol Standards" (STD 1) for the standardization state
   and status of this protocol.  Distribution of this memo is unlimited.

Copyright Notice

   Copyright (C) The Internet Society (1998).  All Rights Reserved.

Abstract

   This memo describes a protocol utilizing security concepts necessary
   for establishing Security Associations (SA) and cryptographic keys in
   an Internet environment.  A Security Association protocol that
   negotiates, establishes, modifies and deletes Security Associations
   and their attributes is required for an evolving Internet, where
   there will be numerous security mechanisms and several options for
   each security mechanism.  The key management protocol must be robust
   in order to handle public key generation for the Internet community
   at large and private key requirements for those private networks with
   that requirement.  The Internet Security Association and Key
   Management Protocol (ISAKMP) defines the procedures for
   authenticating a communicating peer, creation and management of
   Security Associations, key generation techniques, and threat
   mitigation (e.g.  denial of service and replay attacks).  All of
   these are necessary to establish and maintain secure communications
   (via IP Security Service or any other security protocol) in an
   Internet environment.







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RFC 2408                         ISAKMP                    November 1998


Table of Contents

   1 Introduction                                                     4
     1.1 Requirements Terminology  . . . . . . . . . . . . . . . . .  5
     1.2 The Need for Negotiation  . . . . . . . . . . . . . . . . .  5
     1.3 What can be Negotiated?   . . . . . . . . . . . . . . . . .  6
     1.4 Security Associations and Management  . . . . . . . . . . .  7
       1.4.1 Security Associations and Registration  . . . . . . . .  7
       1.4.2 ISAKMP Requirements   . . . . . . . . . . . . . . . . .  8
     1.5 Authentication  . . . . . . . . . . . . . . . . . . . . . .  8
       1.5.1 Certificate Authorities   . . . . . . . . . . . . . . .  9
       1.5.2 Entity Naming   . . . . . . . . . . . . . . . . . . . .  9
       1.5.3 ISAKMP Requirements   . . . . . . . . . . . . . . . . . 10
     1.6 Public Key Cryptography . . . . . . . . . . . . . . . . . . 10
       1.6.1 Key Exchange Properties   . . . . . . . . . . . . . . . 11
       1.6.2 ISAKMP Requirements   . . . . . . . . . . . . . . . . . 12
     1.7 ISAKMP Protection . . . . . . . . . . . . . . . . . . . . . 12
       1.7.1 Anti-Clogging (Denial of Service)   . . . . . . . . . . 12
       1.7.2 Connection Hijacking  . . . . . . . . . . . . . . . . . 13
       1.7.3 Man-in-the-Middle Attacks   . . . . . . . . . . . . . . 13
     1.8 Multicast Communications  . . . . . . . . . . . . . . . . . 13
   2 Terminology and Concepts                                        14
     2.1 ISAKMP Terminology  . . . . . . . . . . . . . . . . . . . . 14
     2.2 ISAKMP Placement  . . . . . . . . . . . . . . . . . . . . . 16
     2.3 Negotiation Phases  . . . . . . . . . . . . . . . . . . . . 16
     2.4 Identifying Security Associations . . . . . . . . . . . . . 17
     2.5 Miscellaneous . . . . . . . . . . . . . . . . . . . . . . . 20
       2.5.1 Transport Protocol  . . . . . . . . . . . . . . . . . . 20
       2.5.2 RESERVED Fields   . . . . . . . . . . . . . . . . . . . 20
       2.5.3 Anti-Clogging Token ("Cookie") Creation   . . . . . . . 20
   3 ISAKMP Payloads                                                 21
     3.1 ISAKMP Header Format  . . . . . . . . . . . . . . . . . . . 21
     3.2 Generic Payload Header  . . . . . . . . . . . . . . . . . . 25
     3.3 Data Attributes . . . . . . . . . . . . . . . . . . . . . . 25
     3.4 Security Association Payload  . . . . . . . . . . . . . . . 27
     3.5 Proposal Payload  . . . . . . . . . . . . . . . . . . . . . 28
     3.6 Transform Payload . . . . . . . . . . . . . . . . . . . . . 29
     3.7 Key Exchange Payload  . . . . . . . . . . . . . . . . . . . 31
     3.8 Identification Payload  . . . . . . . . . . . . . . . . . . 32
     3.9 Certificate Payload . . . . . . . . . . . . . . . . . . . . 33
     3.10 Certificate Request Payload  . . . . . . . . . . . . . . . 34
     3.11 Hash Payload   . . . . . . . . . . . . . . . . . . . . . . 36
     3.12 Signature Payload  . . . . . . . . . . . . . . . . . . . . 37
     3.13 Nonce Payload  . . . . . . . . . . . . . . . . . . . . . . 37
     3.14 Notification Payload   . . . . . . . . . . . . . . . . . . 38
       3.14.1 Notify Message Types   . . . . . . . . . . . . . . . . 40
     3.15 Delete Payload   . . . . . . . . . . . . . . . . . . . . . 41
     3.16 Vendor ID Payload  . . . . . . . . . . . . . . . . . . . . 43



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RFC 2408                         ISAKMP                    November 1998


   4 ISAKMP Exchanges                                                44
     4.1 ISAKMP Exchange Types . . . . . . . . . . . . . . . . . . . 45
       4.1.1 Notation  . . . . . . . . . . . . . . . . . . . . . . . 46
     4.2 Security Association Establishment  . . . . . . . . . . . . 46
       4.2.1 Security Association Establishment Examples   . . . . . 48
     4.3 Security Association Modification . . . . . . . . . . . . . 50
     4.4 Base Exchange . . . . . . . . . . . . . . . . . . . . . . . 51
     4.5 Identity Protection Exchange  . . . . . . . . . . . . . . . 52
     4.6 Authentication Only Exchange  . . . . . . . . . . . . . . . 54
     4.7 Aggressive Exchange . . . . . . . . . . . . . . . . . . . . 55
     4.8 Informational Exchange  . . . . . . . . . . . . . . . . . . 57
   5 ISAKMP Payload Processing                                       58
     5.1 General Message Processing  . . . . . . . . . . . . . . . . 58
     5.2 ISAKMP Header Processing  . . . . . . . . . . . . . . . . . 59
     5.3 Generic Payload Header Processing . . . . . . . . . . . . . 61
     5.4 Security Association Payload Processing . . . . . . . . . . 62
     5.5 Proposal Payload Processing . . . . . . . . . . . . . . . . 63
     5.6 Transform Payload Processing  . . . . . . . . . . . . . . . 64
     5.7 Key Exchange Payload Processing . . . . . . . . . . . . . . 65
     5.8 Identification Payload Processing . . . . . . . . . . . . . 66
     5.9 Certificate Payload Processing  . . . . . . . . . . . . . . 66
     5.10 Certificate Request Payload Processing   . . . . . . . . . 67
     5.11 Hash Payload Processing  . . . . . . . . . . . . . . . . . 69
     5.12 Signature Payload Processing   . . . . . . . . . . . . . . 69
     5.13 Nonce Payload Processing   . . . . . . . . . . . . . . . . 70
     5.14 Notification Payload Processing  . . . . . . . . . . . . . 71
     5.15 Delete Payload Processing  . . . . . . . . . . . . . . . . 73
   6 Conclusions                                                     75
   A ISAKMP Security Association Attributes                          77
     A.1 Background/Rationale  . . . . . . . . . . . . . . . . . . . 77
     A.2 Internet IP Security DOI Assigned Value . . . . . . . . . . 77
     A.3 Supported Security Protocols  . . . . . . . . . . . . . . . 77
     A.4 ISAKMP Identification Type Values . . . . . . . . . . . . . 78
       A.4.1 ID_IPV4_ADDR  . . . . . . . . . . . . . . . . . . . . . 78
       A.4.2 ID_IPV4_ADDR_SUBNET . . . . . . . . . . . . . . . . . . 78
       A.4.3 ID_IPV6_ADDR  . . . . . . . . . . . . . . . . . . . . . 78
       A.4.4 ID_IPV6_ADDR_SUBNET   . . . . . . . . . . . . . . . . . 78
   B Defining a new Domain of Interpretation                         79
     B.1 Situation . . . . . . . . . . . . . . . . . . . . . . . . . 79
     B.2 Security Policies . . . . . . . . . . . . . . . . . . . . . 80
     B.3 Naming Schemes  . . . . . . . . . . . . . . . . . . . . . . 80
     B.4 Syntax for Specifying Security Services . . . . . . . . . . 80
     B.5 Payload Specification . . . . . . . . . . . . . . . . . . . 80
     B.6 Defining new Exchange Types . . . . . . . . . . . . . . . . 80
   Security Considerations                                           81
   IANA Considerations                                               81
   Domain of Interpretation                                          81
   Supported Security Protocols                                      82



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RFC 2408                         ISAKMP                    November 1998


   Acknowledgements                                                  82
   References                                                        82
   Authors' Addresses                                                85
   Full Copyright Statement                                          86

List of Figures

   1   ISAKMP Relationships  . . . . . . . . . . . . . . . . . . . 16
   2   ISAKMP Header Format  . . . . . . . . . . . . . . . . . . . 22
   3   Generic Payload Header  . . . . . . . . . . . . . . . . . . 25
   4   Data Attributes . . . . . . . . . . . . . . . . . . . . . . 26
   5   Security Association Payload  . . . . . . . . . . . . . . . 27
   6   Proposal Payload Format . . . . . . . . . . . . . . . . . . 28
   7   Transform Payload Format  . . . . . . . . . . . . . . . . . 30
   8   Key Exchange Payload Format . . . . . . . . . . . . . . . . 31
   9   Identification Payload Format . . . . . . . . . . . . . . . 32
   10  Certificate Payload Format  . . . . . . . . . . . . . . . . 33
   11  Certificate Request Payload Format  . . . . . . . . . . . . 34
   12  Hash Payload Format . . . . . . . . . . . . . . . . . . . . 36
   13  Signature Payload Format  . . . . . . . . . . . . . . . . . 37
   14  Nonce Payload Format  . . . . . . . . . . . . . . . . . . . 38
   15  Notification Payload Format . . . . . . . . . . . . . . . . 39
   16  Delete Payload Format . . . . . . . . . . . . . . . . . . . 42
   17  Vendor ID Payload Format  . . . . . . . . . . . . . . . . . 44

1 Introduction

   This document describes an Internet Security Association and Key
   Management Protocol (ISAKMP). ISAKMP combines the security concepts
   of authentication, key management, and security associations to
   establish the required security for government, commercial, and
   private communications on the Internet.

   The Internet Security Association and Key Management Protocol
   (ISAKMP) defines procedures and packet formats to establish,
   negotiate, modify and delete Security Associations (SA). SAs contain
   all the information required for execution of various network
   security services, such as the IP layer services (such as header
   authentication and payload encapsulation), transport or application
   layer services, or self-protection of negotiation traffic.  ISAKMP
   defines payloads for exchanging key generation and authentication
   data.  These formats provide a consistent framework for transferring
   key and authentication data which is independent of the key
   generation technique, encryption algorithm and authentication
   mechanism.






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RFC 2408                         ISAKMP                    November 1998


   ISAKMP is distinct from key exchange protocols in order to cleanly
   separate the details of security association management (and key
   management) from the details of key exchange.  There may be many
   different key exchange protocols, each with different security
   properties.  However, a common framework is required for agreeing to
   the format of SA attributes, and for negotiating, modifying, and
   deleting SAs.  ISAKMP serves as this common framework.

   Separating the functionality into three parts adds complexity to the
   security analysis of a complete ISAKMP implementation.  However, the
   separation is critical for interoperability between systems with
   differing security requirements, and should also simplify the
   analysis of further evolution of a ISAKMP server.

   ISAKMP is intended to support the negotiation of SAs for security
   protocols at all layers of the network stack (e.g., IPSEC, TLS, TLSP,
   OSPF, etc.).  By centralizing the management of the security
   associations, ISAKMP reduces the amount of duplicated functionality
   within each security protocol.  ISAKMP can also reduce connection
   setup time, by negotiating a whole stack of services at once.

   The remainder of section 1 establishes the motivation for security
   negotiation and outlines the major components of ISAKMP, i.e.
   Security Associations and Management, Authentication, Public Key
   Cryptography, and Miscellaneous items.  Section 2 presents the
   terminology and concepts associated with ISAKMP. Section 3 describes
   the different ISAKMP payload formats.  Section 4 describes how the
   payloads of ISAKMP are composed together as exchange types to
   establish security associations and perform key exchanges in an
   authenticated manner.  Additionally, security association
   modification, deletion, and error notification are discussed.
   Section 5 describes the processing of each payload within the context
   of ISAKMP exchanges, including error handling and associated actions.
   The appendices provide the attribute values necessary for ISAKMP and
   requirement for defining a new Domain of Interpretation (DOI) within