Updates to the Internet X.509 Public Key Infrastructure Certificate and Certificate Revocation List (CRL) Profile
RFC 6818

Internet Engineering Task Force (IETF)                            P. Yee
Request for Comments: 6818                                        AKAYLA
Updates: 5280                                               January 2013
Category: Standards Track
ISSN: 2070-1721

        Updates to the Internet X.509 Public Key Infrastructure
       Certificate and Certificate Revocation List (CRL) Profile

Abstract

   This document updates RFC 5280, the "Internet X.509 Public Key
   Infrastructure Certificate and Certificate Revocation List (CRL)
   Profile".  This document changes the set of acceptable encoding
   methods for the explicitText field of the user notice policy
   qualifier and clarifies the rules for converting internationalized
   domain name labels to ASCII.  This document also provides some
   clarifications on the use of self-signed certificates, trust anchors,
   and some updated security considerations.

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 5741.

   Information about the current status of this document, any errata,
   and how to provide feedback on it may be obtained at
   http://www.rfc-editor.org/info/rfc6818.

Yee                          Standards Track                    [Page 1]
RFC 6818                 RFC 5280 Clarifications            January 2013

Copyright Notice

   Copyright (c) 2013 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
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   described in the Simplified BSD License.

Table of Contents

   1. Introduction ....................................................2
      1.1. Terminology ................................................3
   2. Update to RFC 5280, Section 3.2: "Certification Paths and Trust" 3
   3. Update to RFC 5280, Section 4.2.1.4: "Certificate Policies" .....3
   4. Update to RFC 5280, Section 6.2: "Using the Path Validation
      Algorithm" ......................................................4
   5. Update to RFC 5280, Section 7.3: "Internationalized
      Domain Names in Distinguished Names" ............................5
   6. Security Considerations .........................................5
   7. Update to RFC 5280, Section 11.1: "Normative References" ........7
   8. Update to RFC 5280, Section 11.2: "Informative References" ......7
   9. References ......................................................7
      9.1. Normative References .......................................7
      9.2. Informative References .....................................7
  10. Acknowledgements ................................................8

1.  Introduction

   This document updates the "Internet X.509 Public Key Infrastructure
   Certificate and Certificate Revocation List (CRL) Profile" [RFC5280].

   This document makes a recommendation that self-signed certificates
   used to convey trust anchor data be marked as certificate authority
   (CA) certificates, which is not always current practice.

   The use of self-signed certificates as trust anchors in Section 6.2
   of [RFC5280] is clarified.  While it is optional to use additional
   information in these certificates in the path validation process,
   [RFC5937] is noted as providing guidance in that regard.

Yee                          Standards Track                    [Page 2]
RFC 6818                 RFC 5280 Clarifications            January 2013

   The acceptable and unacceptable encodings for the explicitText field
   of the user notice policy qualifier are updated to bring them in line
   with existing practice.

   The rules in Section 7.3 of [RFC5280] for ASCII encoding of
   Internationalized Domain Names (IDNs) as Distinguished Names are
   aligned with the rules in Section 7.2 of that document that govern
   IDN encoding as GeneralNames.

   In light of some observed attacks [Prins], the Security