Use of the Elliptic Curve Diffie-Hellman Key Agreement Algorithm with X25519 and X448 in the Cryptographic Message Syntax (CMS)
draft-ietf-curdle-cms-ecdh-new-curves-07

Document Type Active Internet-Draft (curdle WG)
Last updated 2017-05-14 (latest revision 2017-05-11)
Replaces draft-housley-cms-ecdh-new-curves
Stream IETF
Intended RFC status Proposed Standard
Formats plain text pdf html bibtex
Reviews
Stream WG state Submitted to IESG for Publication
Document shepherd Daniel Migault
Shepherd write-up Show (last changed 2017-04-12)
IESG IESG state In Last Call (ends 2017-05-28)
Consensus Boilerplate Yes
Telechat date
Responsible AD Eric Rescorla
Send notices to Daniel Migault <daniel.migault@ericsson.com>
IANA IANA review state IANA - Review Needed
IANA action state None
Internet-Draft                                                R. Housley
Intended status: Standards Track                          Vigil Security
Expires: 11 November 2017                                    11 May 2017

    Use of the Elliptic Curve Diffie-Hellman Key Agreement Algorithm
     with X25519 and X448 in the Cryptographic Message Syntax (CMS)

             <draft-ietf-curdle-cms-ecdh-new-curves-07.txt>

Abstract

   This document describes the conventions for using Elliptic Curve
   Diffie-Hellman (ECDH) key agreement algorithm using curve25519 and
   curve448 in the Cryptographic Message Syntax (CMS).

Status of This Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF).  Note that other groups may also distribute
   working documents as Internet-Drafts.  The list of current Internet-
   Drafts is at http://datatracker.ietf.org/drafts/current/.

   Internet-Drafts are draft documents valid for a maximum of six months
   and may be updated, replaced, or obsoleted by other documents at any
   time.  It is inappropriate to use Internet-Drafts as reference
   material or to cite them other than as "work in progress."

   This Internet-Draft will expire on 11 November 2017.

Copyright Notice

   Copyright (c) 2017 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
   (http://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.

Housley              Using X25519 and X448 with CMS             [Page 1]
Internet-Draft                                                  May 2017

1.  Introduction

   This document describes the conventions for using Elliptic Curve
   Diffie-Hellman (ECDH) key agreement using curve25519 and curve448
   [CURVES] in the Cryptographic Message Syntax (CMS) [CMS].  Key
   agreement is supported in three CMS content types: the enveloped-data
   content type [CMS], authenticated-data content type [CMS], and the
   authenticated-enveloped-data content type [AUTHENV].

   The conventions for using some Elliptic Curve Cryptography (ECC)
   algorithms in CMS are described in [CMSECC].  These conventions cover
   the use of ECDH with some curves other than curve25519 and curve448
   [CURVES].  Those other curves are not deprecated.

   Using curve25519 with Diffie-Hellman key agreement is referred to as
   X25519.  Using curve448 with Diffie-Hellman key agreement is referred
   to as X448.

1.1.  Terminology

   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 [STDWORDS].

1.2.  ASN.1

   CMS values are generated using ASN.1 [X680], which uses the Basic
   Encoding Rules (BER) and the Distinguished Encoding Rules (DER)
   [X690].

2.  Key Agreement

   In 1976, Diffie and Hellman described a means for two parties to
   agree upon a shared secret value in manner that prevents
   eavesdroppers from learning the shared secret value [DH1976].  This
   secret may then be converted into pairwise symmetric keying material
   for use with other cryptographic algorithms.  Over the years, many
   variants of this fundamental technique have been developed.  This
   document describes the conventions for using Ephemeral-Static
   Elliptic Curve Diffie-Hellman (ECDH) key agreement using X25519 and
   X448 [CURVES].

   The originator MUST use an ephemeral public/private key pair that is
   generated on the same elliptic curve as the public key of the
   recipient.  The ephemeral key pair MUST be used for a single CMS
   protected content type, and then it MUST be discarded.  The
   originator obtains the recipient's static public key from the
   recipient's certificate [PROFILE].

Housley              Using X25519 and X448 with CMS             [Page 2]
Internet-Draft                                                  May 2017

   X25519 is described in Section 6.1 of [CURVES], and X448 is described
Show full document text