Internet-Draft COSE: KangarooTwelve, TurboSHAKE, KMAC October 2025
Dang, et al. Expires 29 April 2026 [Page]
Workgroup:
COSE (CBOR Object Signing and Encryption)
Internet-Draft:
draft-bormann-cose-turbo-kanga-kmac-latest
Published:
Intended Status:
Standards Track
Expires:
Authors:
Q. Dang, Ed.
NIST
Y. Name Here, Ed.
org
C. Bormann, Ed.
Universität Bremen TZI

COSE Algorithms for KangarooTwelve, TurboSHAKE and KMAC

Abstract

This document specifies or updates registrations for a number of Keccak-based algorithms in the COSE Algorithms Registry.

RFC 9861 defined and registered four eXtendable-Output Functions (XOFs), hash functions with output of arbitrary length, named TurboSHAKE128, TurboSHAKE256, KT128, and KT256; the present document is intended as the IETF consensus document that is now needed to give these algorithms Recommended status in the COSE registry.

RFC 9861 only hints at MACs that could make use of the TurboSHAKE and KT algorithms. This document completes the specification of HopMAC128 and HopMAC256 from RFC 9861 and also specifies simpler MACs directly based on KT128 and KT256. Finally, this document registers COSE Algorithm identifiers for the KMAC set of algorithms (NIST.SP.800-185).

About This Document

This note is to be removed before publishing as an RFC.

The latest revision of this draft can be found at https://cabo.github.io/turbo-kanga/draft-bormann-cose-turbo-kanga-latest.html. Status information for this document may be found at https://datatracker.ietf.org/doc/draft-bormann-cose-turbo-kanga-kmac/.

Discussion of this document takes place on the CBOR Object Signing and Encryption (COSE) Working Group mailing list (mailto:cose@ietf.org), which is archived at https://mailarchive.ietf.org/arch/browse/cose/. Subscribe at https://www.ietf.org/mailman/listinfo/cose/.

Source for this draft and an issue tracker can be found at https://github.com/cabo/turbo-kanga.

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 https://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 29 April 2026.

Table of Contents

1. Introduction

(Please see abstract.)

1.1. Conventions and 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. MAC Algorithms Based on TurboSHAKE128, TurboSHAKE256, KT128, and KT256

(Add specifications for the HopMACs and for a simple KT based MAC.)

4. SHA-3 based Algorithms (KMAC etc.)

[NIST.SP.800-185]

What algorithms do we want to register? Maybe directly include cSHAKE?

5. IANA Considerations

RFC Ed.: throughout this section, please replace RFC-XXXX with the RFC number of this specification and remove this note.

5.1. Updates to the COSE Algorithms Registry

IANA is requested to update [has updated] the registrations in the COSE Algorithms registry in [IANA.cose] shown in Table 1 by setting the Recommended status column to Yes, and by adding the present document to the Reference column.

In Table 1, the following columns all have the same content and have been elided:

  • Capabilities: [kty]

  • Change Controller: IETF

  • Reference: [RFC9861], RFC-XXXX

  • Recommended: Yes

Table 1: Registrations in COSE Algorithms Updated to Recommended: Yes
Name Value Description
KT256 -264 KT256 XOF
KT128 -263 KT128 XOF
TurboSHAKE256 -262 TurboSHAKE256 XOF
TurboSHAKE128 -261 TurboSHAKE128 XOF

5.2. Additions to Existing Registries

IANA is requested to update [has updated] the registrations in the COSE Algorithms registry in [IANA.cose] shown in Table 1 by setting the Recommended status column to Yes.

In Table 2, the following columns all have the same content and have been elided:

  • Capabilities: [kty]

  • Change Controller: IETF

Table 2: Registrations Added to COSE Algorithms
Name Value Description Reference Recommended
HopMAC256 -nnn HopMAC based on KT256 XOF [RFC9861], RFC-XXXX Yes
HopMAC128 -nnn HopMAC based on KT128 XOF [RFC9861], RFC-XXXX Yes
xxxTurboSHAKE256 -nnn TurboSHAKE256 XOF [RFC9861], RFC-XXXX Yes
xxxTurboSHAKE128 -nnn TurboSHAKE128 XOF [RFC9861], RFC-XXXX Yes
cSHAKE128 -nnn cSHAKE128 [NIST.SP.800-185], RFC-XXXX Yes
cSHAKE256 -nnn cSHAKE256 [NIST.SP.800-185], RFC-XXXX Yes
KMAC128 -nnn KMAC128 [NIST.SP.800-185], RFC-XXXX Yes
KMAC256 -nnn KMAC256 [NIST.SP.800-185], RFC-XXXX Yes
KMACXOF128 -nnn KMACXOF128 [NIST.SP.800-185], RFC-XXXX Yes
KMACXOF256 -nnn KMACXOF256 [NIST.SP.800-185], RFC-XXXX Yes

6. Security Considerations

7. Normative References

[IANA.cose]
IANA, "CBOR Object Signing and Encryption (COSE)", <https://www.iana.org/assignments/cose>.
[NIST.SP.800-185]
Kelsey, J., Change, S., Perlner, R., and NIST, "SHA-3 derived functions: cSHAKE, KMAC, TupleHash and ParallelHash", NIST Special Publications (General) 800-185, DOI 10.6028/NIST.SP.800-185, , <https://nvlpubs.nist.gov/nistpubs/SpecialPublications/NIST.SP.800-185.pdf>.
[RFC2119]
Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, , <https://www.rfc-editor.org/rfc/rfc2119>.
[RFC8174]
Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, , <https://www.rfc-editor.org/rfc/rfc8174>.
[RFC9861]
Viguier, B., Wong, D., Ed., Van Assche, G., Ed., Dang, Q., Ed., and J. Daemen, Ed., "KangarooTwelve and TurboSHAKE", RFC 9861, DOI 10.17487/RFC9861, , <https://www.rfc-editor.org/rfc/rfc9861>.

Appendix A. Examples

TBD

Acknowledgments

TBD

Authors' Addresses

Quynh Dang (editor)
National Institute of Standards and Technology
Your Name Here (editor)
org
Carsten Bormann (editor)
Universität Bremen TZI
Postfach 330440
D-28359 Bremen
Germany