X.509 RFC 5280 PKI CRL

Network Working Group D. Cooper

Request for Comments: 5280 NIST

Obsoletes: 3280, 4325, 4630 S. Santesson

Category: Standards Track Microsoft

S. Farrell

Trinity College Dublin

S. Boeyen

Entrust

R. Housley

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.

Abstract

This memo profiles the X.509 v3 certificate and X.509 v2 certificate

revocation list (CRL) for use in the Internet. An overview of this

approach and model is provided as an introduction. The X.509 v3

extensions. An algorithm for X.509 certification path validation is

described. An ASN.1 module and examples are provided in the

appendices.

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RFC 5280 PKIX Certificate and CRL Profile May 2008

Table of Contents

1. Introduction ....................................................4

2. Requirements and Assumptions ....................................6

2.1. Communication and Topology .................................7

2.2. Acceptability Criteria .....................................7

2.3. User Expectations ..........................................7

2.4. Administrator Expectations .................................8

3. Overview of Approach ............................................8

3.1. X.509 Version 3 Certificate ................................9

3.2. Certification Paths and Trust .............................10

4.1. Basic Certificate Fields ..................................16

4.1.1. Certificate Fields .................................17

4.1.1.3. signatureValue ............................18

4.1.2. TBSCertificate .....................................18

4.1.2.1. Version ...................................19

4.1.2.2. Serial Number .............................19

4.1.2.3. Signature .................................19

4.1.2.4. Issuer ....................................20

4.1.2.5. Validity ..................................22

4.1.2.5.1. UTCTime ........................23

4.1.2.6. Subject ...................................23

4.1.2.8. Unique Identifiers ........................25

4.1.2.9. Extensions ................................26

4.2. Certificate Extensions ....................................26

4.2.1.6. Subject Alternative Name ..................35

4.2.1.7. Issuer Alternative Name ...................38

4.2.1.8. Subject Directory Attributes ..............39

4.2.1.13. CRL Distribution Points ..................45

4.2.1.14. Inhibit anyPolicy ........................48

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RFC 5280 PKIX Certificate and CRL Profile May 2008

4.2.1.15. Freshest CRL (a.k.a. Delta CRL

Distribution Point) ......................48

4.2.2. Private Internet Extensions ........................49

4.2.2.1. Authority Information Access ..............49

4.2.2.2. Subject Information Access ................51

5. CRL and CRL Extensions Profile .................................54

5.1. CRL Fields ................................................55

5.1.1. CertificateList Fields .............................56

5.1.1.1. tbsCertList ...............................56

5.1.1.2. signatureAlgorithm ........................57

5.1.1.3. signatureValue ............................57

5.1.2.4. This Update ...............................58

5.1.2.5. Next Update ...............................59

5.2. CRL Extensions ............................................60

5.2.1. Authority Key Identifier ...........................60

5.2.2. Issuer Alternative Name ............................60

5.2.3. CRL Number .........................................61

5.2.4. Delta CRL Indicator ................................62

5.2.5. Issuing Distribution Point .........................65

5.2.6. Freshest CRL (a.k.a. Delta CRL Distribution

Point) .............................................67

5.3. CRL Entry Extensions ......................................69

5.3.2. Invalidity Date ....................................70

5.3.3. Certificate Issuer .................................70

6. Certification Path Validation ..................................71

6.1.6. Outputs ............................................89

6.2. Using the Path Validation Algorithm .......................89

6.3. CRL Validation ............................................90

7.1. Internationalized Names in Distinguished Names ............96

7.2. Internationalized Domain Names in GeneralName .............97

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RFC 5280 PKIX Certificate and CRL Profile May 2008

7.3. Internationalized Domain Names in Distinguished Names .....98

7.4. Internationalized Resource Identifiers ....................98

7.5. Internationalized Electronic Mail Addresses ..............100

8. Security Considerations .......................................100

9. IANA Considerations ...........................................105

10. Acknowledgments ..............................................105

11. References ...................................................105

11.1. Normative References ....................................105

11.2. Informative References ..................................107

Appendix A. Pseudo-ASN.1 Structures and OIDs ....................110

A.1. Explicitly Tagged Module, 1988 Syntax ....................110

C.2. End Entity Certificate Using RSA .........................140

C.3. End Entity Certificate Using DSA .........................143

1. Introduction

This specification is one part of a family of standards for the X.509

Public Key Infrastructure (PKI) for the Internet.

This specification profiles the format and semantics of certificates

and certificate revocation lists (CRLs) for the Internet PKI.

Procedures are described for processing of certification paths in the

appendices for all data structures defined or referenced.

Section 2 describes Internet PKI requirements and the assumptions

that affect the scope of this document. Section 3 presents an

architectural model and describes its relationship to previous IETF

identification of ISO/IEC/ITU-T and ANSI extensions that may be

useful in the Internet PKI. The profiles are presented in the 1988

Abstract Syntax Notation One (ASN.1) rather than the 1997 ASN.1

Implementations are REQUIRED to derive the same results but are not

required to use the specified procedures.

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RFC 5280 PKIX Certificate and CRL Profile May 2008

Procedures for identification and encoding of public key materials

and digital signatures are defined in [RFC3279], [RFC4055], and

[RFC4491]. Implementations of this specification are not required to

use any particular cryptographic algorithms. However, conforming

implementations that use the algorithms identified in [RFC3279],

[RFC4055], and [RFC4491] MUST identify and encode the public key

materials and digital signatures as described in those

specifications.

Finally, three appendices are provided to aid implementers. Appendix

A contains all ASN.1 structures defined or referenced within this

This specification obsoletes [RFC3280]. Differences from RFC 3280

* Enhanced support for internationalized names is specified in

Section 7, with rules for encoding and comparing

Internationalized Domain Names, Internationalized Resource

Identifiers (IRIs), and distinguished names. These rules are

aligned with comparison rules established in current RFCs,

including [RFC3490], [RFC3987], and [RFC4518].

* Sections 4.1.2.4 and 4.1.2.6 incorporate the conditions for

specified in [RFC4630]. Where in use by an established PKI,

name chaining failures or incorrect processing of name

constraints.

as critical. RFC 3280 required that the policy mappings

extension be marked as non-critical.

* The Authority Information Access (AIA) CRL extension, as

specified in [RFC4325], was added as Section 5.2.7.

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