PQ/T Hybrid Composite Signatures for JOSE and COSE
draft-prabel-jose-pq-composite-sigs-00
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| Document | Type | Active Internet-Draft (individual) | |
|---|---|---|---|
| Authors | Lucas Prabel , Sun Shuzhou | ||
| Last updated | 2024-10-14 | ||
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draft-prabel-jose-pq-composite-sigs-00
JOSE L. Prabel
Internet-Draft S. Sun
Intended status: Standards Track Huawei
Expires: 17 April 2025 14 October 2024
PQ/T Hybrid Composite Signatures for JOSE and COSE
draft-prabel-jose-pq-composite-sigs-00
Abstract
This document describes JSON Object Signing and Encryption (JOSE) and
CBOR Object Signing and Encryption (COSE) serializations for PQ/T
hybrid composite signatures. The composite algorithms described
combine ML-DSA as the post-quantum component and ECDSA as the
traditional component.
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://example.com/LATEST. Status information for this document may
be found at https://datatracker.ietf.org/doc/draft-prabel-jose-pq-
composite-sigs/.
Discussion of this document takes place on the Javascript Object
Signing and Encryption Working Group mailing list
(mailto:jose@ietf.org), which is archived at
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https://www.ietf.org/mailman/listinfo/jose/.
Source for this draft and an issue tracker can be found at
https://github.com/USER/REPO.
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
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This Internet-Draft will expire on 17 April 2025.
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document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
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Please review these documents carefully, as they describe your rights
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Conventions and Definitions . . . . . . . . . . . . . . . . . 4
3. Composite Keys and Signatures Structures . . . . . . . . . . 5
3.1. Composite Key Structures . . . . . . . . . . . . . . . . 5
3.2. Composite Signature Structures . . . . . . . . . . . . . 5
3.3. Encoding Rules . . . . . . . . . . . . . . . . . . . . . 6
4. Composite Signature Algorithms . . . . . . . . . . . . . . . 7
4.1. JOSE algorithms . . . . . . . . . . . . . . . . . . . . . 7
4.2. COSE algorithms . . . . . . . . . . . . . . . . . . . . . 8
5. Composite Signature Key Types . . . . . . . . . . . . . . . . 9
5.1. JOSE Key Type . . . . . . . . . . . . . . . . . . . . . . 9
5.2. COSE Key type . . . . . . . . . . . . . . . . . . . . . . 10
6. Composite Signature Web Key and Key Type Parameters . . . . . 10
6.1. JSON Web Key Parameters . . . . . . . . . . . . . . . . . 10
6.2. COSE Key Type Parameters . . . . . . . . . . . . . . . . 11
7. Security Considerations . . . . . . . . . . . . . . . . . . . 11
8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 12
8.1. JOSE Algorithms . . . . . . . . . . . . . . . . . . . . . 12
8.1.1. MLDSA44-ES256 . . . . . . . . . . . . . . . . . . . . 12
8.1.2. MLDSA65-ES512 . . . . . . . . . . . . . . . . . . . . 12
8.1.3. MLDSA87-ES512 . . . . . . . . . . . . . . . . . . . . 13
8.2. JOSE Key Types . . . . . . . . . . . . . . . . . . . . . 13
8.2.1. AKP-EC . . . . . . . . . . . . . . . . . . . . . . . 13
8.3. JOSE Web Key Parameters . . . . . . . . . . . . . . . . . 13
8.3.1. Public Key . . . . . . . . . . . . . . . . . . . . . 14
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8.3.2. Private Key . . . . . . . . . . . . . . . . . . . . . 14
8.3.3. Others . . . . . . . . . . . . . . . . . . . . . . . 14
8.4. COSE Algorithms . . . . . . . . . . . . . . . . . . . . . 14
8.4.1. MLDSA44-ES256 . . . . . . . . . . . . . . . . . . . . 14
8.4.2. MLDSA65-ES512 . . . . . . . . . . . . . . . . . . . . 15
8.4.3. MLDSA87-ES512 . . . . . . . . . . . . . . . . . . . . 15
8.5. COSE Key Types . . . . . . . . . . . . . . . . . . . . . 15
8.5.1. AKP-EC2 . . . . . . . . . . . . . . . . . . . . . . . 15
8.6. COSE Key Type Parameters . . . . . . . . . . . . . . . . 16
8.6.1. Public Key . . . . . . . . . . . . . . . . . . . . . 16
8.6.2. Private Key . . . . . . . . . . . . . . . . . . . . . 16
8.6.3. Others . . . . . . . . . . . . . . . . . . . . . . . 16
9. References . . . . . . . . . . . . . . . . . . . . . . . . . 16
9.1. Normative References . . . . . . . . . . . . . . . . . . 16
9.2. Informative References . . . . . . . . . . . . . . . . . 17
Appendix A. Examples . . . . . . . . . . . . . . . . . . . . . . 18
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 18
1. Introduction
The impact of a potential Cryptographically Relevant Quantum Computer
(CRQC) on algorithms whose security is based on mathematical problems
such as integer factorisation or discrete logarithms over finite
fields or elliptic curves raises the need for new algorithms that are
perceived to be secure against CRQC as well as classical computers.
Such algorithms are called post-quantum, while algorithms based on
integer factorisation or discrete logarithms are called traditional.
While switching from a traditional algorithm to a post-quantum one
intends to strengthen the security against an adversary possessing a
quantum computer, the lack of maturing time of post-quantum
algorithms compared to traditional algorithms raises uncertainty
about their security.
Thus, the joint use of a traditional algorithm and a post-quantum
algorithm in protocols represents a solution to this problem by
providing security as long as at least one of the traditional or
post-quantum components remains secure.
This document describes JSON Object Signing and Encryption (JOSE) and
CBOR Object Signing and Encryption (COSE) serializations for hybrid
composite signatures. The composite algorithms described combine ML-
DSA as the post-quantum component and ECDSA as the traditional
component.
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2. Conventions and Definitions
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.
This document follows the terminology for post-quantum hybrid schemes
defined in [I-D.draft-ietf-pquip-pqt-hybrid-terminology-04].
This section recalls some of this terminology, but also adds other
definitions used throughout the whole document:
"Asymmetric Traditional Cryptographic Algorithm": An asymmetric
cryptographic algorithm based on integer factorisation, finite field
discrete logarithms, elliptic curve discrete logarithms, or related
mathematical problems. A related mathematical problem is one that
can be solved by solving the integer factorisation, finite field
discrete logarithm or elliptic curve discrete logarithm problem.
Where there is little risk of confusion asymmetric traditional
cryptographic algorithms can also be referred to as traditional
algorithms for brevity.
"Post-Quantum Algorithm": An asymmetric cryptographic algorithm that
is intended to be secure against attacks using quantum computers as
well as classical computers. As with all cryptography, it always
remains the case that attacks, either quantum or classical, may be
found against post-quantum algorithms. Therefore it should not be
assumed that just because an algorithm is designed to provide post-
quantum security it will not be compromised.
"Component Algorithm": Each cryptographic algorithm that forms part
of a cryptographic scheme.
"Post-Quantum Traditional (PQ/T) Hybrid Scheme": A multi-algorithm
scheme where at least one component algorithm is a post-quantum
algorithm and at least one is a traditional algorithm.
"PQ/T Hybrid Digital Signature": A multi-algorithm digital signature
scheme made up of two or more component digital signature algorithms
where at least one is a post-quantum algorithm and at least one is a
traditional algorithm.
"Composite Algorithm": An algorithm which is a sequence of two
component algorithms, as defined in
[I-D.draft-ietf-lamps-pq-composite-sigs-02].
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3. Composite Keys and Signatures Structures
The structures of the composite keys and composite signatures follow
the approach of [I-D.draft-ietf-lamps-pq-composite-sigs-02]. This
design was chosen so that composite keys and signatures can be used
as a drop-in replacement in JOSE / COSE object formats. This section
gives some details about their construction.
3.1. Composite Key Structures
Composite public and private keys are generated by calling the key
generation functions of the two component algorithms and
concatenating the keys in an order given by the registered composite
algorithm.
Composite Public Key <- Public Key of the 1st Algorithm || Public Key
of the 2nd Algorithm
and
Composite Private Key <- Private Key of the 1st Algorithm || Private
Key of the 2nd Algorithm
For the composite algorithms described in this document (ML-DSA with
ECDSA), the Key Generation process is as follows:
(pk_1, sk_1) <- MLDSA.KeyGen()
(pk_2 = (x,y), sk_2 = d) <- ECDSA.KeyGen()
Composite Public Key <- pk_1 || pk_2 = pk_1 || x || y
Composite Private Key <- sk_1 || sk_2 = sk_1 || d
Point compression for ECDSA is not performed for the "AKP-EC" JSON
Web Key Type but can be performed for the "AKP-EC2" COSE Key Type.
Both key types are defined in Section 5.
In this document, as it is specified in [FIPS.204], the ML-DSA
private key is stored as a 32-byte seed, which is sufficient to
generate the full expanded private key.
3.2. Composite Signature Structures
Composite signatures are generated by:
* pre-hashing the message to be signed;
* concatenating it with a domain separator;
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* encoding the resulting message;
* calling the two signature component algorithms on this new
message;
* concatenating the two output signatures.
For the composite algorithms described in this document (ML-DSA with
ECDSA), the signature process of a message M is as follows:
M' <- Domain || HASH(M)
M' <- Encode(M')
sig_1 <- MLDSA.Sign(sk_1, M')
sig_2 <- ECDSA.Sign(sk_2, M')
Composite Signature <- (sig_1, sig_2)
The domain separator is defined as the octets of the ASCII
representation of the Composite Signature "alg" (algorithm) Header
Parameter value.
For JOSE (resp. COSE), M' is base64url-encoded (resp. binary
encoded) before signature computations.
3.3. Encoding Rules
In each combination, the byte streams of the keys or signatures are
directly concatenated.
Signature of the 1st Algorithm || Signature of the 2nd Algorithm
Since all combinations presented in this document start with the ML-
DSA algorithm and the key or signature sizes are fixed as defined in
[FIPS.204], it is unambiguous to encode or decode a composite key or
signature.
Table 1 lists sizes of the three parameter sets of the ML-DSA
algorithm.
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+===========+=============+============+================+
| | Private Key | Public Key | Signature Size |
+===========+=============+============+================+
| ML-DSA-44 | 2560 | 1312 | 2420 |
+-----------+-------------+------------+----------------+
| ML-DSA-65 | 4032 | 1952 | 3309 |
+-----------+-------------+------------+----------------+
| ML-DSA-87 | 4896 | 2592 | 4627 |
+-----------+-------------+------------+----------------+
Table 1: Sizes (in bytes) of keys and signatures of
ML-DSA
4. Composite Signature Algorithms
The ML-DSA signature scheme supports three possible parameter sets,
each of which corresponding to a specific security strength. See
[FIPS.204] for more considerations on that matter.
The hybrid composite schemes are described in more detail in
[I-D.draft-ietf-lamps-pq-composite-sigs-02].
The traditional signature algorithm for each combination in Table 2
and Table 3 was chosen to match the security level of the ML-DSA
post-quantum component. More precisely, NIST security levels 1-3 are
matched with 256-bit curves and NIST security levels 4-5 are matched
with 384-bit elliptic curves.
4.1. JOSE algorithms
The following table defines a list of algorithms associated with
specific PQ/T combinations to be registered in [IANA.JOSE].
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+=============+=========+===================+=========+===========+
|Name |First | Second Algorithm |Pre-Hash |Description|
| |Algorithm| | | |
+=============+=========+===================+=========+===========+
|MLDSA44-ES256|ML-DSA-44| ecdsa-with-SHA256 |id-sha256|Composite |
| | | with secp256r1 | |Signature |
| | | | |with ML- |
| | | | |DSA-44 and |
| | | | |ECDSA using|
| | | | |P-256 curve|
| | | | |and SHA-256|
+-------------+---------+-------------------+---------+-----------+
|MLDSA65-ES512|ML-DSA-65| ecdsa-with-SHA512 |id-sha512|Composite |
| | | with secp256r1 | |Signature |
| | | | |with ML- |
| | | | |DSA-65 and |
| | | | |ECDSA using|
| | | | |P-256 curve|
| | | | |and SHA-512|
+-------------+---------+-------------------+---------+-----------+
|MLDSA87-ES512|ML-DSA-87| ecdsa-with-SHA512 |id-sha512|Composite |
| | | with secp384r1 | |Signature |
| | | | |with ML- |
| | | | |DSA-87 and |
| | | | |ECDSA using|
| | | | |P-384 curve|
| | | | |and SHA-512|
+-------------+---------+-------------------+---------+-----------+
Table 2: JOSE Composite Signature Algorithms for ML-DSA
Examples can be found in Appendix A.
4.2. COSE algorithms
The following table defines a list of algorithms associated with
specific PQ/T combinations to be registered in [IANA.COSE].
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+=============+==========+=========+=========+===========+=========+
|Name |COSE Value|First |Second |Description| |
| | |Algorithm|Algorithm| | |
+=============+==========+=========+=========+===========+=========+
|MLDSA44-ES256|TBD |ML-DSA-44|ecdsa- |id-sha256 |Composite|
| |(request | |with- | |Signature|
| |assignment| |SHA256 | |with ML- |
| |-51) | |with | |DSA-44 |
| | | |secp256r1| |and ECDSA|
| | | | | |using |
| | | | | |P-256 |
| | | | | |curve and|
| | | | | |SHA-256 |
+-------------+----------+---------+---------+-----------+---------+
|MLDSA65-ES512|TBD |ML-DSA-65|ecdsa- |id-sha512 |Composite|
| |(request | |with- | |Signature|
| |assignment| |SHA512 | |with ML- |
| |-52) | |with | |DSA-65 |
| | | |secp256r1| |and ECDSA|
| | | | | |using |
| | | | | |P-256 |
| | | | | |curve and|
| | | | | |SHA-512 |
+-------------+----------+---------+---------+-----------+---------+
|MLDSA87-ES512|TBD |ML-DSA-87|ecdsa- |id-sha512 |Composite|
| |(request | |with- | |Signature|
| |assignment| |SHA512 | |with ML- |
| |-53) | |with | |DSA-87 |
| | | |secp384r1| |and ECDSA|
| | | | | |using |
| | | | | |P-384 |
| | | | | |curve and|
| | | | | |SHA-512 |
+-------------+----------+---------+---------+-----------+---------+
Table 3: COSE Composite Signature Algorithms for ML-DSA
Examples can be found in Appendix A.
5. Composite Signature Key Types
5.1. JOSE Key Type
This document requests the registration of the following key type in
[IANA.JOSE], for use in the optional JWS Header parameter "jwk".
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"AKP" stands for "Algorithm Key Pair" and is used in this document,
as in [I-D.draft-ietf-cose-dilithium-03], to express the ML-DSA
public and private keys. When this key type is used, the JSON Web
Key Parameter "alg" is REQUIRED.
+========+==========================================+
| kty | Description |
+========+==========================================+
| AKP-EC | JWK key type for composite signature |
| | with ECDSA as the traditional component. |
+--------+------------------------------------------+
Table 4: JWK key type for composite algorithm
Examples can be found in Appendix A.
5.2. COSE Key type
This document requests the registration of the following key type in
[IANA.COSE].
"AKP" stands for "Algorithm Key Pair" and is used in this document,
as in [I-D.draft-ietf-cose-dilithium-03], to express the ML-DSA
public and private keys. When this key type is used, the COSE Key
Common Parameter "alg" is REQUIRED.
+=========+=====+==========================================+
| Name | kty | Description |
+=========+=====+==========================================+
| AKP-EC2 | TBD | COSE key type for composite algorithm |
| | | with ECDSA as the traditional component. |
+---------+-----+------------------------------------------+
Table 5: COSE key type for composite algorithm
Examples can be found in Appendix A.
6. Composite Signature Web Key and Key Type Parameters
6.1. JSON Web Key Parameters
This document requests IANA to register the entries described in this
section and summarised in the following Table 7 to the JSON Web Key
Parameters Registry.
It also requests to add "AKP-EC" as a usable "kty" value for the
parameters "crv", "x", "y" and "d".
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+=========+===========+========+===========+==========+=============+
|Parameter|Parameter |Used |Parameter |Change |Specification|
|Name |Description|with |Information|Controller|Document(s) |
| | |"kty" |Class | | |
| | |Value(s)| | | |
+=========+===========+========+===========+==========+=============+
|pub |Public Key |AKP-EC |Public |IETF |n\a |
+---------+-----------+--------+-----------+----------+-------------+
|priv |Private Key|AKP-EC |Private |IETF |n\a |
+---------+-----------+--------+-----------+----------+-------------+
Table 6: JSON AKP-EC Web Key Parameters
6.2. COSE Key Type Parameters
This document requests IANA to register the entries described in this
section and summarised in the following Table 7 to the COSE Key Type
Parameters Registry.
+===============+======+=======+===========+==============+
| Key Type | Name | Label | CBOR Type | Description |
+===============+======+=======+===========+==============+
| TBD (request | crv | -1 | int / | EC |
| assignment 8) | | | tstr | identifier |
+---------------+------+-------+-----------+--------------+
| TBD (request | x | -2 | bstr | x-coordinate |
| assignment 8) | | | | |
+---------------+------+-------+-----------+--------------+
| TBD (request | y | -3 | bstr / | y-coordinate |
| assignment 8) | | | bool | |
+---------------+------+-------+-----------+--------------+
| TBD (request | d | -4 | bstr | EC Private |
| assignment 8) | | | | key |
+---------------+------+-------+-----------+--------------+
| TBD (request | pub | -5 | bstr | Public Key |
| assignment 8) | | | | |
+---------------+------+-------+-----------+--------------+
| TBD (request | priv | -6 | bstr | Private Key |
| assignment 8) | | | | |
+---------------+------+-------+-----------+--------------+
Table 7: COSE AKP-EC2 Key Parameters
7. Security Considerations
The security considerations of [RFC7515], [RFC7517], [RFC9053] and
[FIPS.204] also apply to this document.
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All security issues that are pertinent to any cryptographic
application must be addressed by JWS/JWK agents. Protecting the
user's private key and employing countermeasures to various attacks
constitute a priority.
For security properties and security issues related to the use of a
hybrid signature scheme, the user can refer to
[I-D.draft-ietf-pquip-hybrid-signature-spectrums-00]. For more
information about hybrid composite signature schemes and the
different hybrid combinations that appear in this document, the user
can read [I-D.draft-ietf-lamps-pq-composite-sigs-02].
8. IANA Considerations
8.1. JOSE Algorithms
The following values of the JWS "alg" (algorithm) are requested to be
added to the "JSON Web Signature and Encryption Algorithms" registry.
They are represented following the registration template provided in
[RFC7518].
8.1.1. MLDSA44-ES256
* Algorithm Name: MLDSA44-ES256
* Algorithm Description: Composite Signature with ML-DSA-44 and
ECDSA using P-256 curve and SHA-256
* Algorithm Usage Location(s): alg
* JOSE Implementation Requirements: Optional
* Change Controller: IETF
* Specification Document(s): n/a
* Algorithm Analysis Documents(s): TBD
8.1.2. MLDSA65-ES512
* Algorithm Name: MLDSA65-ES512
* Algorithm Description: Composite Signature with ML-DSA-65 and
ECDSA using P-256 curve and SHA-512
* Algorithm Usage Location(s): alg
* JOSE Implementation Requirements: Optional
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* Change Controller: IETF
* Specification Document(s): n/a
* Algorithm Analysis Documents(s): TBD
8.1.3. MLDSA87-ES512
* Algorithm Name: MLDSA87-ES512
* Algorithm Description: Composite Signature with ML-DSA-87 and
ECDSA using P-384 curve and SHA-512
* Algorithm Usage Location(s): alg
* JOSE Implementation Requirements: Optional
* Change Controller: IETF
* Specification Document(s): n/a
* Algorithm Analysis Documents(s): TBD
8.2. JOSE Key Types
IANA is requested to add the following entries to the JSON Web Key
Types Registry.
8.2.1. AKP-EC
* "kty" Parameter Value: AKP-EC
* Key Type Description: Composite signature algorithm with ECDSA as
the traditional component
* JOSE Implementation Requirements: Optional
* Change Controller: IETF
* Specification Document(s): n/a
8.3. JOSE Web Key Parameters
IANA is requested to add the following entries to the JSON Web Key
Parameters Registry.
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8.3.1. Public Key
* Parameter Name: pub
* Parameter Description: Public or verification key
* Used with "kty" Value(s): AKP-EC
* Parameter Information Class: Public
* Change Controller: IETF
* Specification Document(s): n/a
8.3.2. Private Key
* Parameter Name: priv
* Parameter Description: Secret, private or signing key
* Used with "kty" Value(s): AKP-EC
* Parameter Information Class: Private
* Change Controller: IETF
* Specification Document(s): n/a
8.3.3. Others
The key parameters registered in [IANA.JOSE] for use with the kty
values "EC" should also be usable with the kty value "AKP-EC" defined
in this document.
8.4. COSE Algorithms
The following values are requested to be added to the "COSE
Algorithms" registry. They are represented following the
registration template provided in [RFC9053], [RFC9054].
8.4.1. MLDSA44-ES256
* Name: MLDSA44-ES256
* Value: TBD (request assignment -51)
* Description: Composite Signature with ML-DSA-44 and ECDSA using
P-256 curve and SHA-256
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* Capabilities: [kty]
* Change Controller: IETF
* Reference: n/a
* Recommended: Yes
8.4.2. MLDSA65-ES512
* Name: MLDSA65-ES512
* Value: TBD (request assignment -52)
* Description: Composite Signature with ML-DSA-65 and ECDSA using
P-256 curve and SHA-512
* Capabilities: [kty]
* Change Controller: IETF
* Reference: n/a
* Recommended: Yes
8.4.3. MLDSA87-ES512
* Name: MLDSA87-ES512
* Value: TBD (request assignment -53)
* Description: Composite Signature with ML-DSA-87 and ECDSA using
P-384 curve and SHA-512
* Capabilities: [kty]
* Change Controller: IETF
* Reference: n/a
* Recommended: Yes
8.5. COSE Key Types
8.5.1. AKP-EC2
* Name: AKP-EC2
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* Value: TBD (request assignment 8)
* Description: COSE Key Type for Composite Signature Algorithm with
ECDSA as the traditional component
* Capabilities: [kty(8)]
* Reference: n/a
8.6. COSE Key Type Parameters
8.6.1. Public Key
* Key Type: TBD
* Name: public_key
* Label: -1
* CBOR Type: bstr
* Description: Public key
* Reference: n/a
8.6.2. Private Key
* Key Type: TBD
* Name: private_key
* Label: -2
* CBOR Type: bstr
* Description: Private key
* Reference: n/a
8.6.3. Others
The key parameters registered in [IANA.COSE] for use with the kty
value "EC2" should also be usable with the kty value "AKP-EC2"
defined in this document.
9. References
9.1. Normative References
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[IANA.COSE]
IANA, "CBOR Object Signing and Encryption (COSE)", n.d.,
<https://www.iana.org/assignments/cose/cose.xhtml>.
[IANA.JOSE]
IANA, "JSON Object Signing and Encryption (JOSE)", n.d.,
<https://www.iana.org/assignments/jose/jose.xhtml>.
[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/rfc/rfc2119>.
[RFC7515] Jones, M., Bradley, J., and N. Sakimura, "JSON Web
Signature (JWS)", RFC 7515, DOI 10.17487/RFC7515, May
2015, <https://www.rfc-editor.org/rfc/rfc7515>.
[RFC7517] Jones, M., "JSON Web Key (JWK)", RFC 7517,
DOI 10.17487/RFC7517, May 2015,
<https://www.rfc-editor.org/rfc/rfc7517>.
[RFC7518] Jones, M., "JSON Web Algorithms (JWA)", RFC 7518,
DOI 10.17487/RFC7518, May 2015,
<https://www.rfc-editor.org/rfc/rfc7518>.
[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/rfc/rfc8174>.
9.2. Informative References
[FIPS.204] National Institute of Standards and Technology (NIST),
"Module-Lattice-Based Digital Signature Standard", August
2024, <https://nvlpubs.nist.gov/nistpubs/FIPS/
NIST.FIPS.204.pdf>.
[I-D.draft-ietf-cose-dilithium-03]
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-03, 2
June 2024, <https://datatracker.ietf.org/doc/html/draft-
ietf-cose-dilithium-03>.
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[I-D.draft-ietf-lamps-pq-composite-sigs-02]
Ounsworth, M., Gray, J., Pala, M., Klaußner, J., and S.
Fluhrer, "Composite ML-DSA for use in Internet PKI", Work
in Progress, Internet-Draft, draft-ietf-lamps-pq-
composite-sigs-02, 8 July 2024,
<https://datatracker.ietf.org/doc/html/draft-ietf-lamps-
pq-composite-sigs-02>.
[I-D.draft-ietf-pquip-hybrid-signature-spectrums-00]
Bindel, N., Hale, B., Connolly, D., and F. D, "Hybrid
signature spectrums", Work in Progress, Internet-Draft,
draft-ietf-pquip-hybrid-signature-spectrums-00, 24 May
2024, <https://datatracker.ietf.org/doc/html/draft-ietf-
pquip-hybrid-signature-spectrums-00>.
[I-D.draft-ietf-pquip-pqt-hybrid-terminology-04]
D, F., P, M., and B. Hale, "Terminology for Post-Quantum
Traditional Hybrid Schemes", Work in Progress, Internet-
Draft, draft-ietf-pquip-pqt-hybrid-terminology-04, 10
September 2024, <https://datatracker.ietf.org/doc/html/
draft-ietf-pquip-pqt-hybrid-terminology-04>.
[RFC9053] Schaad, J., "CBOR Object Signing and Encryption (COSE):
Initial Algorithms", RFC 9053, DOI 10.17487/RFC9053,
August 2022, <https://www.rfc-editor.org/rfc/rfc9053>.
[RFC9054] Schaad, J., "CBOR Object Signing and Encryption (COSE):
Hash Algorithms", RFC 9054, DOI 10.17487/RFC9054, August
2022, <https://www.rfc-editor.org/rfc/rfc9054>.
Appendix A. Examples
Will be added in later versions.
Authors' Addresses
Lucas Prabel
Huawei
Email: lucas.prabel@huawei.com
Sun Shuzhou
Huawei
Email: sunshuzhou@huawei.com
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