Internet Engineering Task Force (IETF)                            T. Ito
Request for Comments: 8813                               SECOM CO., LTD.
Updates: 5480                                                  S. Turner
Category: Standards Track                                          sn3rd
ISSN: 2070-1721                                              August 2020


  Clarifications for Elliptic Curve Cryptography Subject Public Key
                             Information

Abstract

  This document updates RFC 5480 to specify semantics for the
  keyEncipherment and dataEncipherment key usage bits when used in
  certificates that support Elliptic Curve Cryptography.

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.

  Information about the current status of this document, any errata,
  and how to provide feedback on it may be obtained at
  https://www.rfc-editor.org/info/rfc8813.

Copyright Notice

  Copyright (c) 2020 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
  Provisions Relating to IETF Documents
  (https://trustee.ietf.org/license-info) 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.

Table of Contents

  1.  Introduction
  2.  Terminology
  3.  Updates to Section 3
  4.  Security Considerations
  5.  IANA Considerations
  6.  Normative References
  Authors' Addresses

1.  Introduction

  [RFC5480] specifies the syntax and semantics for the Subject Public
  Key Information field in certificates that support Elliptic Curve
  Cryptography.  As part of these semantics, it defines what
  combinations are permissible for the values of the key usage
  extension [RFC5280].  [RFC5480] specifies 7 of the 9 values; it makes
  no mention of the keyEncipherment and dataEncipherment key usage
  bits.  This document corrects this omission by updating Section 3 of
  [RFC5480] to make it clear that neither keyEncipherment nor the
  dataEncipherment key usage bits are set for key agreement algorithms
  defined therein.  The additions are to be made to the end of
  Section 3 of [RFC5480].

2.  Terminology

  The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
  "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
  "OPTIONAL" in this document are to be interpreted as described in
  BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all
  capitals, as shown here.

3.  Updates to Section 3

  If the keyUsage extension is present in a certificate that indicates
  id-ecPublicKey in SubjectPublicKeyInfo, then the following values
  MUST NOT be present:

     keyEncipherment; and
     dataEncipherment.

  If the keyUsage extension is present in a certificate that indicates
  id-ecDH or id-ecMQV in SubjectPublicKeyInfo, then the following
  values also MUST NOT be present:

     keyEncipherment; and
     dataEncipherment.

4.  Security Considerations

  This document introduces no new security considerations beyond those
  found in [RFC5480].

5.  IANA Considerations

  This document has no IANA actions.

6.  Normative References

  [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
             Requirement Levels", BCP 14, RFC 2119,
             DOI 10.17487/RFC2119, March 1997,
             <https://www.rfc-editor.org/info/rfc2119>.

  [RFC5280]  Cooper, D., Santesson, S., Farrell, S., Boeyen, S.,
             Housley, R., and W. Polk, "Internet X.509 Public Key
             Infrastructure Certificate and Certificate Revocation List
             (CRL) Profile", RFC 5280, DOI 10.17487/RFC5280, May 2008,
             <https://www.rfc-editor.org/info/rfc5280>.

  [RFC5480]  Turner, S., Brown, D., Yiu, K., Housley, R., and T. Polk,
             "Elliptic Curve Cryptography Subject Public Key
             Information", RFC 5480, DOI 10.17487/RFC5480, March 2009,
             <https://www.rfc-editor.org/info/rfc5480>.

  [RFC8174]  Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
             2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
             May 2017, <https://www.rfc-editor.org/info/rfc8174>.

Authors' Addresses

  Tadahiko Ito
  SECOM CO., LTD.

  Email: [email protected]


  Sean Turner
  sn3rd

  Email: [email protected]

You are viewing proxied material from gopher.fnord.one. The copyright of proxied material belongs to its original authors. Any comments or complaints in relation to proxied material should be directed to the original authors of the content concerned. Please see the disclaimer for more details.