Internet-Draft | jose-cose-sphincs-plus | October 2024 |
Prorock, et al. | Expires 23 April 2025 | [Page] |
- Workgroup:
- CBOR Object Signing and Encryption
- Internet-Draft:
- draft-ietf-cose-sphincs-plus-05
- Published:
- Intended Status:
- Standards Track
- Expires:
SLH-DSA for JOSE and COSE
Abstract
This document describes JOSE and COSE serializations for SLH-DSA, which was derived from SPHINCS+, a Post-Quantum Cryptography (PQC) based digital signature scheme. This document does not define any new cryptography, only seralizations of existing cryptographic systems described in [FIPS-205]. Note to RFC Editor: This document should not proceed to AUTH48 until NIST completes paramater tuning and selection as a part of the PQC standardization process.¶
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://cose-wg.github.io/draft-ietf-cose-sphincs-plus/draft-ietf-cose-sphincs-plus.html. Status information for this document may be found at https://datatracker.ietf.org/doc/draft-ietf-cose-sphincs-plus/.¶
Discussion of this document takes place on the CBOR Object Signing and Encryption 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/cose-wg/draft-ietf-cose-sphincs-plus.¶
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/.¶
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This Internet-Draft will expire on 23 April 2025.¶
Copyright Notice
Copyright (c) 2024 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 Revised BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Revised BSD License.¶
1. Introduction
This document describes JSON Object Signing and Encryption (JOSE) and CBOR Object Signing and Encryption (COSE) serializations for the Stateless Hash-Based Digital Signature Standard (SLH-DSA), which was derived from Version 3.1 of SPHINCS+, a Post-Quantum Cryptography (PQC) based digital signature scheme.¶
This document does not define any new cryptography, only serializations of existing cryptographic systems described in [FIPS-205].¶
This document builds on the Algorithm Key Pair (AKP) type as defined in [I-D.draft-ietf-cose-dilithium]. The AKP type enables flexible representation of keys used across different post-quantum cryptographic algorithms, including SLH-DSA.¶
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. The SLH-DSA Algorithm Family
The SLH-DSA Signature Scheme is parameterized to support different security levels.¶
This document requests the registration of the following algorithms in [IANA.jose]:¶
Name | alg | Description |
---|---|---|
SLH-DSA-SHA2-128s | SLH-DSA-SHA2-128s | JSON Web Signature Algorithm for SLH-DSA-SHA2-128s |
SLH-DSA-SHAKE-128s | SLH-DSA-SHAKE-128s | JSON Web Signature Algorithm for SLH-DSA-SHAKE-128s |
SLH-DSA-SHA2-128f | SLH-DSA-SHA2-128f | JSON Web Signature Algorithm for SLH-DSA-SHA2-128f |
This document requests the registration of the following algorithms in [IANA.cose]:¶
Name | alg | Description |
---|---|---|
SLH-DSA-SHA2-128s | TBD (requested assignment -51) | CBOR Object Signing Algorithm for SLH-DSA-SHA2-128s |
SLH-DSA-SHAKE-128s | TBD (requested assignment -52) | CBOR Object Signing Algorithm for SLH-DSA-SHAKE-128s |
SLH-DSA-SHA2-128f | TBD (requested assignment -53) | CBOR Object Signing Algorithm for SLH-DSA-SHA2-128f |
4. SLH-DSA Keys
Private and Public Keys are produced to enable the sign and verify operations for each of the SLH-DSA Algorithms. The SLH-DSA Algorithm Family uses the Algorithm Key Pair (AKP) key type, as defined in [I-D.draft-ietf-cose-dilithium]. This ensures compatibility across different cryptographic algorithms that use AKP for key representation.¶
The specific algorithms for SLH-DSA, such as SLH-DSA-SHA2-128s, SLH-DSA-SHAKE-128s, and SLH-DSA-SHA2-128f, are defined in this document and are used in the alg value of an AKP key representation to specify the algorithm that corresponds to the key. Like ML-DSA keys, SLH-DSA keys use the AKP Key Type.¶
The thumbprints for SLH-DSA keys are also computed according to the process described in [I-D.draft-ietf-cose-dilithium]¶
5. Security Considerations
The security considerations of [RFC7515], [RFC7517] and [RFC9053] applies to this specification as well.¶
A detailed security analysis of SLH-DSA is beyond the scope of this specification, see [FIPS-205] for additional details.¶
The following considerations apply to all parameter sets described in this specification.¶
5.1. Validating public keys
All algorithms in that operate on public keys require first validating those keys. For the sign, verify and proof schemes, the use of KeyValidate is REQUIRED.¶
5.2. Side channel attacks
Implementations of the signing algorithm SHOULD protect the secret key from side-channel attacks. Multiple best practices exist to protect against side-channel attacks. Any implementation of the SLH-DSA signing algorithms SHOULD utilize the following best practices at a minimum:¶
-
Constant timing - the implementation should ensure that constant time is utilized in operations¶
-
Sequence and memory access persistance - the implementation SHOULD execute the exact same sequence of instructions (at a machine level) with the exact same memory access independent of which polynomial is being operated on.¶
-
Uniform sampling - care should be given in implementations to preserve the property of uniform sampling in implementation and to prevent information leakage.¶
5.3. Randomness considerations
It is recommended that the all nonces are from a trusted source of randomness.¶
6. IANA Considerations
6.1. Additions to Existing Registries
6.1.1. New COSE Algorithms
IANA is requested to add the following entries to the COSE Algorithms Registry. The following completed registration templates are provided as described in RFC9053 and RFC9054.¶
6.1.2. New JOSE Algorithms
IANA is requested to add the following entries to the JSON Web Signature and Encryption Algorithms Registry. The following completed registration templates are provided as described in RFC7518.¶
6.1.2.1. SLH-DSA-SHA2-128s
6.1.2.2. SLH-DSA-SHAKE-128s
7. References
7.1. Normative References
- [I-D.draft-ietf-cose-dilithium]
- Prorock, M., Steele, O., Misoczki, R., Osborne, M., and C. Cloostermans, "ML-DSA for JOSE and COSE", Work in Progress, Internet-Draft, draft-ietf-cose-dilithium-04, , <https://datatracker.ietf.org/doc/html/draft-ietf-cose-dilithium-04>.
- [IANA.cose]
- IANA, "CBOR Object Signing and Encryption (COSE)", <https://www.iana.org/assignments/cose>.
- [IANA.jose]
- IANA, "JSON Object Signing and Encryption (JOSE)", <https://www.iana.org/assignments/jose>.
- [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>.
- [RFC7515]
- Jones, M., Bradley, J., and N. Sakimura, "JSON Web Signature (JWS)", RFC 7515, DOI 10.17487/RFC7515, , <https://www.rfc-editor.org/rfc/rfc7515>.
- [RFC7517]
- Jones, M., "JSON Web Key (JWK)", RFC 7517, DOI 10.17487/RFC7517, , <https://www.rfc-editor.org/rfc/rfc7517>.
- [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>.
- [RFC9053]
- Schaad, J., "CBOR Object Signing and Encryption (COSE): Initial Algorithms", RFC 9053, DOI 10.17487/RFC9053, , <https://www.rfc-editor.org/rfc/rfc9053>.
7.2. Informative References
- [FIPS-205]
- "Stateless Hash-Based Digital Signature Standard", n.d., <https://doi.org/10.6028/NIST.FIPS.205>.
- [NIST-PQC-2022]
- "Selected Algorithms 2022", n.d., <https://csrc.nist.gov/Projects/post-quantum-cryptography/selected-algorithms-2022>.
Appendix A. Examples
A.1. JOSE
A.1.1. Key Pair
{ "kty": "AKP", "alg": "SLH-DSA-SHA2-128s", "pub": "V53SIdVF...uvw2nuCQ", "priv": "V53SIdVF...cDKLbsBY" }
{ "kty": "AKP", "alg": "SLH-DSA-SHA2-128s", "pub": "V53SIdVF...uvw2nuCQ" }
A.1.2. Thumbprint
The thumbprint is computed as described in¶
A.1.3. JSON Web Signature
{ "alg": "SLH-DSA-SHA2-128s" }
eyJhbGciOiJ...LCJraWQiOiI0MiJ9\ .\ eyJpc3MiOiJ1cm46d...XVpZDo0NTYifQ\ .\ 5MSEgQ0dZB4SeLC...AAAAAABIhMUE
A.2. COSE
A.2.1. Key Pair
{ / COSE Key / 1: 7, / AKP Key Type / 3: -51, / SLH-DSA-SHA2-128s Algorithm / -1: h'7803c0f9...3f6e2c70', / AKP Private Key / -2: h'7803c0f9...3bba7abd', / AKP Public Key / } ~~~ {: #SLH-DSA-SHA2-128s-private-cose-key title="Example SLH-DSA-SHA2-128s Private COSE Key"} ~~~~ cbor-diag { / COSE Key / 1: 7, / AKP Key Type / 3: -51, / SLH-DSA-SHA2-128s Algorithm / -2: h'7803c0f9...3bba7abd', / AKP Public Key / }
A.2.2. Thumbprint URI
TODO¶
A.2.3. COSE Sign 1
/ cose-sign1 / 18( [ / protected / <<{ / algorithm / 1 : -51 / SLH-DSA-SHA2-128s / }>> / unprotected / {}, / payload / h'66616b65', / signature / h'53e855e8...0f263549' ] )
Acknowledgments
TODO acknowledge.¶