RFC 6161

Elliptic Curve Algorithms for Cryptographic Message Syntax (CMS) Encrypted Key Package Content Type

📅 published April 2011, from ietf

RFC 6161 🎀 Elliptic Curve Algorithms for CMS Encrypted Key Package Content Type

bestie, this one is about bringing elliptic curves into CMS, and the title block has all the tea ☕✨

  • Stream: Internet Engineering Task Force (IETF) 🌸
  • Request for Comments: 6161 💖
  • Author: Sean Turner, IECA 👑
  • Category: Standards Track 🔥
  • Date: April 2011 🗓️
  • Updates: 6033 🦋
  • ISSN: 2070-1721 🧚

Abstract ✨

okay so this doc explains how to use a few Elliptic Curve crypto algorithms with the Cryptographic Message Syntax (CMS) encrypted key package content type 🔐. It's specifically about making Elliptic Curve Diffie-Hellman (ECDH) work with EnvelopedData, and Elliptic Curve Digital Signature Algorithm (ECDSA) work with SignedData 💅. It extends RFC 6033, so it's giving sequel energy 🎬.

Status of This Memo 🌈

this is an Internet Standards Track document, so it's officially a whole thing 👑. It's a product of the Internet Engineering Task Force (IETF) and represents the consensus of the IETF community 🫶. It got public review and was approved for publication by the Internet Engineering Steering Group (IESG) 💜. If you want more on Internet Standards, check Section 2 of RFC 5741 📖.

Info about the current status, any errata, and how to give feedback can be found at http://www.rfc-editor.org/info/rfc6161 🔗.

the legal stuff, kept exactly as written 🙈:

Copyright (c) 2011 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.

1. Introduction ✨

so this doc is about using Elliptic Curve crypto with the CMS encrypted key package content type [RFC6032] 🔑. Specifically, it covers the conventions for two CMS content types: EnvelopedData [RFC5652] and SignedData [RFC5652] 💖. It amends [RFC6033], and you need to already be familiar with [RFC6033] and [RFC5753] to keep up 📚.

The best part? It doesn't invent any new algorithms 🙅‍♀️. It just points at algorithms that already exist 💅.

1.1. 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 [RFC2119] 🎀. These are the official requirement-level words, so treat them like sacred scripture 🙏.

2. EnvelopedData 🦋

when key agreement is used, standard (as opposed to cofactor) ECDH [RFC6090][RFC5753] MAY be supported 💜. Standard ECDH is the one we're talking about here, not the cofactor version 🤓.

3. SignedData 🌸

if an implementation encapsulates EncryptedKeyPackage with SignedData [RFC5652], then it MAY support the signature scheme ECDSA [RFC6090][RFC5753] 🫶. It's optional but iconic if you do it ✨.

4. Public Key Sizes 🔑

the easiest way to implement SignedData and EnvelopedData is with public key certificates [RFC5280][RFC5480] 📜. And if an implementation supports ECDSA or ECDH, then it MUST support keys on the P-256 curve 🔥. Non-negotiable, bestie 💅.

5. Security Considerations 💀

the security considerations from [RFC5280], [RFC5480], [RFC5652], [RFC5753], [RFC6033], and [RFC6090] all apply 🚨. Please read every one of those docs. Your crypto depends on it 😭.

6. Normative References 📚

the full reference list, copied exactly so nothing gets lost 🧾:

[RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
           Requirement Levels", BCP 14, RFC 2119, March 1997.

[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, May 2008.

[RFC5480]  Turner, S., Brown, D., Yiu, K., Housley, R., and T. Polk,
           "Elliptic Curve Cryptography Subject Public Key
           Information", RFC 5480, March 2009.

[RFC5652]  Housley, R., "Cryptographic Message Syntax (CMS)", STD 70,
           RFC 5652, September 2009.

[RFC5753]  Turner, S. and D. Brown, "Use of Elliptic Curve
           Cryptography (ECC) Algorithms in Cryptographic Message
           Syntax (CMS)", RFC 5753, January 2010.

[RFC6032]  Turner, S. and R. Housley, "Cryptographic Message Syntax
           (CMS) Encrypted Key Package Content Type", RFC 6032,
           December 2010.

[RFC6033]  Turner, S., "Algorithms for Cryptographic Message Syntax
           (CMS) Encrypted Key Package Content Type", RFC 6033,
           December 2010.

[RFC6090]  McGrew, D., Igoe, K., and M. Salter, "Fundamental Elliptic
           Curve Cryptography Algorithms", RFC 6090, February 2011.

Author's Address 🧚

Sean Turner
IECA, Inc.
3057 Nutley Street, Suite 106
Fairfax, VA 22031
USA

EMail: turners@ieca.com

that's the whole RFC, bestie 🌈💖✨

📦 where this page comes from