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Use of the SHA3 One-Way Hash Functions in the Cryptographic Message Syntax (CMS)
RFC 9688

Document Type RFC - Proposed Standard (November 2024)
Author Russ Housley
Last updated 2024-11-18
RFC stream Internet Engineering Task Force (IETF)
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IESG Responsible AD Deb Cooley
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RFC 9688


Internet Engineering Task Force (IETF)                        R. Housley
Request for Comments: 9688                                Vigil Security
Category: Standards Track                                  November 2024
ISSN: 2070-1721

  Use of the SHA3 One-Way Hash Functions in the Cryptographic Message
                              Syntax (CMS)

Abstract

   This document describes the conventions for using the one-way hash
   functions in the SHA3 family with the Cryptographic Message Syntax
   (CMS).  The SHA3 family can be used as a message digest algorithm, as
   part of a signature algorithm, as part of a message authentication
   code, or as part of a Key Derivation Function (KDF).

Status of This Memo

   This is an Internet Standards Track document.

   This document is a product of the Internet Engineering Task Force
   (IETF).  It represents the consensus of the IETF community.  It has
   received public review and has been approved for publication by the
   Internet Engineering Steering Group (IESG).  Further information on
   Internet Standards is available in Section 2 of RFC 7841.

   Information about the current status of this document, any errata,
   and how to provide feedback on it may be obtained at
   https://www.rfc-editor.org/info/rfc9688.

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
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   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.

Table of Contents

   1.  Introduction
     1.1.  ASN.1
     1.2.  Terminology
   2.  Message Digest Algorithms
   3.  Signature Algorithms
     3.1.  RSASSA PKCS#1 v1.5 with SHA3
     3.2.  ECDSA with SHA3
   4.  Message Authentication Codes Using HMAC and SHA3
   5.  Key Derivation Functions
     5.1.  HKDF with SHA3
     5.2.  KMAC128-KDF and KMAC256-KDF
     5.3.  KDF2 and KDF3 with SHA3
   6.  Security Considerations
   7.  IANA Considerations
   8.  References
     8.1.  Normative References
     8.2.  Informative References
   Appendix A.  ASN.1 Module
   Acknowledgements
   Author's Address

1.  Introduction

   The Cryptographic Message Syntax (CMS) [RFC5652] is used to digitally
   sign, digest, authenticate, or encrypt arbitrary message contents.
   This specification describes the use of the four one-way hash
   functions in the SHA3 family (SHA3-224, SHA3-256, SHA3-384, and
   SHA3-512) [SHA3] with the CMS.  In addition, this specification
   describes the use of these four one-way hash functions with the
   RSASSA PKCS#1 version 1.5 signature algorithm [RFC8017] and the
   Elliptic Curve Digital Signature Algorithm (ECDSA) [DSS] with the CMS
   signed-data content type.

   This document should not be confused with [RFC8702], which defines
   conventions for using the SHAKE family of SHA3-based extensible
   output functions with the CMS.

1.1.  ASN.1

   CMS values are generated with ASN.1 [X.680], using the Basic Encoding
   Rules (BER) and the Distinguished Encoding Rules (DER) [X.690].

1.2.  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.

2.  Message Digest Algorithms

   One-way hash functions are also referred to as message digest
   algorithms.  This section specifies the conventions employed by CMS
   implementations that support SHA3-224, SHA3-256, SHA3-384, and
   SHA3-512 [SHA3].

   Digest algorithm identifiers are located in the SignedData
   digestAlgorithms field, the SignerInfo digestAlgorithm field, the
   DigestedData digestAlgorithm field, and the AuthenticatedData
   digestAlgorithm field.

   Digest values are located in the DigestedData digest field and the
   Message Digest authenticated attribute.  In addition, digest values
   are input to signature algorithms.

   SHA3-224, SHA3-256, SHA3-384, and SHA3-512 produce output values with
   224, 256, 384, and 512 bits, respectively.  The object identifiers
   for these four one-way hash functions are as follows:

      hashAlgs OBJECT IDENTIFIER ::= { joint-iso-itu-t(2) country(16)
          us(840) organization(1) gov(101) csor(3) nistAlgorithm(4) 2 }

      id-sha3-224 OBJECT IDENTIFIER ::= { hashAlgs 7 }

      id-sha3-256 OBJECT IDENTIFIER ::= { hashAlgs 8 }

      id-sha3-384 OBJECT IDENTIFIER ::= { hashAlgs 9 }

      id-sha3-512 OBJECT IDENTIFIER ::= { hashAlgs 10 }

   When using the id-sha3-224, id-sha3-s256, id-sha3-384, or id-sha3-512
   algorithm identifiers, the parameters field MUST be absent, not NULL
   but absent.

3.  Signature Algorithms

   This section specifies the conventions employed by CMS
   implementations that support the four SHA3 one-way hash functions
   with the RSASSA PKCS#1 v1.5 signature algorithm [RFC8017] and the
   ECDSA [DSS] with the CMS signed-data content type.

   Signature algorithm identifiers are located in the SignerInfo
   signatureAlgorithm field of SignedData.  Also, signature algorithm
   identifiers are located in the SignerInfo signatureAlgorithm field of
   countersignature attributes.

   Signature values are located in the SignerInfo signature field of
   SignedData.  Also, signature values are located in the SignerInfo
   signature field of countersignature attributes.

3.1.  RSASSA PKCS#1 v1.5 with SHA3

   The RSASSA PKCS#1 v1.5 is defined in [RFC8017].  When RSASSA PKCS#1
   v1.5 is used in conjunction with one of the SHA3 one-way hash
   functions, the object identifiers are:

      OID ::= OBJECT IDENTIFIER

      sigAlgs OBJECT IDENTIFIER ::= { joint-iso-itu-t(2) country(16)
          us(840) organization(1) gov(101) csor(3) nistAlgorithm(4) 3 }

      id-rsassa-pkcs1-v1-5-with-sha3-224 OID ::= { sigAlgs 13 }

      id-rsassa-pkcs1-v1-5-with-sha3-256 OID ::= { sigAlgs 14 }

      id-rsassa-pkcs1-v1-5-with-sha3-384 OID ::= { sigAlgs 15 }

      id-rsassa-pkcs1-v1-5-with-sha3-512 OID ::= { sigAlgs 16 }

   The algorithm identifier for RSASSA PKCS#1 v1.5 subject public keys
   in certificates is specified in [RFC3279], and it is repeated here
   for convenience:

      rsaEncryption OBJECT IDENTIFIER ::= { iso(1) member-body(2)
          us(840) rsadsi(113549) pkcs(1) pkcs-1(1) 1 }

   When the rsaEncryption, id-rsassa-pkcs1-v1-5-with-sha3-224, id-
   rsassa-pkcs1-v1-5-with-sha3-256, id-rsassa-pkcs1-v1-5-with-sha3-384,
   and id-rsassa-pkcs1-v1-5-with-sha3-512 algorithm identifiers are
   used, the AlgorithmIdentifier parameters field MUST contain NULL.

   When the rsaEncryption algorithm identifier is used, the RSA public
   key, which is composed of a modulus and a public exponent, MUST be
   encoded using the RSAPublicKey type as specified in [RFC3279].  The
   output of this encoding is carried in the certificate subject public
   key.  The definition of RSAPublicKey is repeated here for
   convenience:

      RSAPublicKey ::= SEQUENCE {
         modulus INTEGER, -- n
         publicExponent INTEGER } -- e

   When signing, the RSASSA PKCS#1 v1.5 signature algorithm generates a
   single value.  That value is used directly as the signature value.

3.2.  ECDSA with SHA3

   The ECDSA is defined in [DSS].  When the ECDSA is used in conjunction
   with one of the SHA3 one-way hash functions, the object identifiers
   are:

      sigAlgs OBJECT IDENTIFIER ::= { joint-iso-itu-t(2) country(16)
          us(840) organization(1) gov(101) csor(3) nistAlgorithm(4) 3 }

      id-ecdsa-with-sha3-224 OBJECT IDENTIFIER ::= { sigAlgs 9 }

      id-ecdsa-with-sha3-256 OBJECT IDENTIFIER ::= { sigAlgs 10 }

      id-ecdsa-with-sha3-384 OBJECT IDENTIFIER ::= { sigAlgs 11 }

      id-ecdsa-with-sha3-512 OBJECT IDENTIFIER ::= { sigAlgs 12 }

   When the id-sha3-224, id-sha3-s256, id-sha3-384, or id-sha3-512
   algorithm identifier is used, the parameters field MUST be absent,
   not NULL but absent.

   When the id-ecdsa-with-sha3-224, id-ecdsa-with-sha3-256, id- ecdsa-
   with-sha3-384, and id-ecdsa-with-sha3-512 algorithm identifiers are
   used, the parameters field MUST be absent, not NULL but absent.

   The conventions for ECDSA public keys are as specified in [RFC5480].
   The ECParameters associated with the ECDSA public key in the signers
   certificate SHALL apply to the verification of the signature.

   When signing, the ECDSA algorithm generates two values.  These values
   are commonly referred to as r and s.  To easily transfer these two
   values as one signature, they MUST be ASN.1 encoded using the ECDSA-
   Sig-Value defined in [RFC3279], which is repeated here for
   convenience:

    ECDSA-Sig-Value ::= SEQUENCE { r INTEGER, s
   INTEGER }

4.  Message Authentication Codes Using HMAC and SHA3

   This section specifies the conventions employed by CMS
   implementations that support the Hashed Message Authentication Code
   (HMAC) [RFC2104] with SHA3 message authentication code (MAC).

   MAC algorithm identifiers are located in the AuthenticatedData
   macAlgorithm field.

   MAC values are located in the AuthenticatedData mac field.

   When HMAC is used in conjunction with one of the SHA3 one-way hash
   functions, the object identifiers are:

      hashAlgs OBJECT IDENTIFIER ::= { joint-iso-itu-t(2) country(16)
          us(840) organization(1) gov(101) csor(3) nistAlgorithm(4) 2 }

      id-hmacWithSHA3-224 OBJECT IDENTIFIER ::= { hashAlgs 13 }

      id-hmacWithSHA3-256 OBJECT IDENTIFIER ::= { hashAlgs 14 }

      id-hmacWithSHA3-384 OBJECT IDENTIFIER ::= { hashAlgs 15 }

      id-hmacWithSHA3-512 OBJECT IDENTIFIER ::= { hashAlgs 16 }

   When the id-hmacWithSHA3-224, id-hmacWithSHA3-256, id-
   hmacWithSHA3-384, and id-hmacWithSHA3-512 algorithm identifiers are
   used, the parameters field MUST be absent, not NULL but absent.

5.  Key Derivation Functions

   The CMS KEMRecipientInfo structure [RFC9629] is one place where
   algorithm identifiers for key-derivation functions are needed.

5.1.  HKDF with SHA3

   This section assigns four algorithm identifiers that can be employed
   by CMS implementations that support the HMAC-based Extract-and-Expand
   Key Derivation Function (HKDF) [RFC5869] with the SHA3 family of hash
   functions.

   When HKDF is used in conjunction with one of the SHA3 one-way hash
   functions, the object identifiers are:

      id-alg OBJECT IDENTIFIER ::= { iso(1) member-body(2)
          us(840) rsadsi(113549) pkcs(1) pkcs-9(9) smime(16) 3 }

      id-alg-hkdf-with-sha3-224 OBJECT IDENTIFIER ::= { id-alg 32 }

      id-alg-hkdf-with-sha3-256 OBJECT IDENTIFIER ::= { id-alg 33 }

      id-alg-hkdf-with-sha3-384 OBJECT IDENTIFIER ::= { id-alg 34 }

      id-alg-hkdf-with-sha3-512 OBJECT IDENTIFIER ::= { id-alg 35 }

   When id-alg-hkdf-with-sha3-224, id-alg-hkdf-with-sha3-256, id-alg-
   hkdf-with-sha3-384, or id-alg-hkdf-with-sha3-512 is used in an
   algorithm identifier, the parameters field MUST be absent, not NULL
   but absent.

5.2.  KMAC128-KDF and KMAC256-KDF

   This section specifies the conventions employed by CMS
   implementations that employ either KMAC128 or KMAC256 as KDFs as
   defined in Section 4.4 of [NIST.SP.800-108r1-upd1].

   KMAC128 and KMAC256 are specified in [NIST.SP.800-185].  The use of
   KMAC128 and KMAC256 as KDFs are defined as follows:

      KMAC128-KDF is KMAC128(K, X, L, S).

      KMAC256-KDF is KMAC256(K, X, L, S).

   The parameters to the KMAC128 and KMAC256 functions are:

   K  The input key-derivation key.  The length of K MUST be less than
      2^2040.

   X  The context, which contains the ASN.1 DER encoding of
      CMSORIforKEMOtherInfo when the KDF is used with [RFC9629].

   L  The output length in bits.  L MUST be greater than or equal to 0
      and MUST be less than 2^2040.

   S  The optional customization label, such as "KDF" (0x4B4446).  The
      length of S MUST be less than 2^2040.

   The K parameter is known to all authorized parties; it is often the
   output of a KEM Decap() operation.  The X parameter is assembled from
   data that is transmitted by the originator.  The L parameter is
   determined by the size of the output keying material.  The S
   parameter is optional, and if it is provided by the originator, it is
   passed in the parameters field of the KDF algorithm identifier.

   When KMAC128-KDF or KMAC256-KDF is used, the object identifiers are:

      hashAlgs OBJECT IDENTIFIER ::= { joint-iso-itu-t(2) country(16)
          us(840) organization(1) gov(101) csor(3) nistAlgorithm(4) 2 }

      id-kmac128 OBJECT IDENTIFIER ::= { hashAlgs 21 }

      id-kmac256 OBJECT IDENTIFIER ::= { hashAlgs 22 }

   When id-kmac128 or id-kmac256 is used as part of an algorithm
   identifier, the parameters field MUST be absent when there is no
   customization label (S).  If any value is provided for S, then the
   parameters field MUST be present and contain the value of S, encoded
   as Customization.

      Customization ::= OCTET STRING

5.3.  KDF2 and KDF3 with SHA3

   This section specifies the conventions employed by CMS
   implementations that employ either the KDF2 or KDF3 functions defined
   in [ANS-X9.44-2007].  The CMS KEMRecipientInfo structure [RFC9629] is
   one place where algorithm identifiers for key-derivation functions
   are needed.

   The key-derivation function algorithm identifier is an object
   identifier and optional parameters.  When KDF2 and KDF3 are used,
   they are identified by the id-kdf-kdf2 and id-kdf-kdf3 object
   identifiers, respectively.  The key-derivation function algorithm
   identifier parameters carry a message digest algorithm identifier,
   which indicates the hash function that is being employed.  To support
   SHA3, the key-derivation function algorithm identifier parameters
   contain an algorithm identifier from Section 2.

      x9-44 OBJECT IDENTIFIER ::= { iso(1) identified-organization(3)
          tc68(133) country(16) x9(840) x9Standards(9) x9-44(44) }

      x9-44-components OBJECT IDENTIFIER ::= { x9-44 components(1) }

      id-kdf-kdf2 OBJECT IDENTIFIER ::= { x9-44-components kdf2(1) }

      id-kdf-kdf3 OBJECT IDENTIFIER ::= { x9-44-components kdf3(2) }

6.  Security Considerations

   Implementations must protect the signer's private key.  Compromise of
   the signer's private key permits masquerade.

   Implementations must protect the key-derivation key.  Compromise of
   the key-derivation key permits others to derive the derived keying
   material, which would result in loss of confidentiality, integrity,
   or authentication, depending on the use of the derived keying
   material.

   When more than two parties share the same message-authentication key,
   data origin authentication is not assured.  Any party that knows the
   message-authentication key can compute a valid MAC; therefore, the
   content could originate from any one of the parties.

   Implementations must randomly generate message-authentication keys
   and one-time values, such as the a per-message secret number (called
   the k value) when generating an ECDSA signature.  In addition, the
   generation of public/private key pairs relies on a random numbers.
   The use of inadequate pseudorandom number generators (PRNGs) to
   generate cryptographic values can result in little or no security.
   Instead of brute-force searching the whole key space, an attacker may
   find it much easier to reproduce the PRNG environment that produced
   the keys and then search the resulting small set of possibilities.
   The generation of quality random numbers is difficult.  [RFC4086]
   offers important guidance in this area, and Appendix 3 of FIPS PUB
   186-4 [DSS] provides some PRNG techniques.

   Implementers should be aware that cryptographic algorithms become
   weaker with time.  As new cryptanalysis techniques are developed and
   computing performance improves, the work factor to break a particular
   cryptographic algorithm will reduce.  Therefore, cryptographic
   algorithm implementations should be modular, allowing new algorithms
   to be readily inserted.  That is, implementers should be prepared to
   regularly update the set of algorithms in their implementations.

7.  IANA Considerations

   IANA has assigned one object identifier for the ASN.1 module in
   Appendix A in the "SMI Security for S/MIME Module Identifiers
   (1.2.840.113549.1.9.16.0)" registry [IANA-MOD]:

      id-mod-sha3-oids-2023 OBJECT IDENTIFIER ::= {
         iso(1) member-body(2) us(840) rsadsi(113549) pkcs(1)
         pkcs-9(9) smime(16) mod(0) 78 }

   IANA has assigned four object identifiers for the HKDF using SHA3
   algorithm identifiers in the "SMI Security for S/MIME Algorithms
   (1.2.840.113549.1.9.16.3)" registry [IANA-ALG]:

      id-alg-hkdf-with-sha3-224 OBJECT IDENTIFIER ::= { id-alg 32 }

      id-alg-hkdf-with-sha3-256 OBJECT IDENTIFIER ::= { id-alg 33 }

      id-alg-hkdf-with-sha3-384 OBJECT IDENTIFIER ::= { id-alg 34 }

      id-alg-hkdf-with-sha3-512 OBJECT IDENTIFIER ::= { id-alg 35 }

8.  References

8.1.  Normative References

   [ANS-X9.44-2007]
              American National Standards Institute, "Public Key
              Cryptography for the Financial Services Industry -- Key
              Establishment Using Integer Factorization Cryptography",
              ANSI X9.44-2007 (R2017), 2017,
              <https://webstore.ansi.org/standards/ascx9/
              ansix9442007r2017>.

   [DSS]      National Institute of Standards and Technology, "Digital
              Signature Standard (DSS)", FIPS PUB 186-5,
              DOI 10.6028/NIST.FIPS.186-5, 3 February 2023,
              <https://nvlpubs.nist.gov/nistpubs/FIPS/
              NIST.FIPS.186-5.pdf>.

   [NIST.SP.800-108r1-upd1]
              Chen, L., "Recommendation for Key Derivation Using
              Pseudorandom Functions", NIST SP 800-108r1-upd1,
              DOI 10.6028/NIST.SP.800-108r1-upd1, 2 February 2024,
              <https://nvlpubs.nist.gov/nistpubs/SpecialPublications/
              NIST.SP.800-108r1-upd1.pdf>.

   [NIST.SP.800-185]
              Kelsey, J., Chang, S., and R. Perlner, "SHA-3 Derived
              Functions: cSHAKE, KMAC, TupleHash and ParallelHash", NIST
              SP 800-185, DOI 10.6028/NIST.SP.800-185, December 2016,
              <https://nvlpubs.nist.gov/nistpubs/SpecialPublications/
              NIST.SP.800-185.pdf>.

   [RFC2104]  Krawczyk, H., Bellare, M., and R. Canetti, "HMAC: Keyed-
              Hashing for Message Authentication", RFC 2104,
              DOI 10.17487/RFC2104, February 1997,
              <https://www.rfc-editor.org/info/rfc2104>.

   [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/info/rfc2119>.

   [RFC3279]  Bassham, L., Polk, W., and R. Housley, "Algorithms and
              Identifiers for the Internet X.509 Public Key
              Infrastructure Certificate and Certificate Revocation List
              (CRL) Profile", RFC 3279, DOI 10.17487/RFC3279, April
              2002, <https://www.rfc-editor.org/info/rfc3279>.

   [RFC5480]  Turner, S., Brown, D., Yiu, K., Housley, R., and T. Polk,
              "Elliptic Curve Cryptography Subject Public Key
              Information", RFC 5480, DOI 10.17487/RFC5480, March 2009,
              <https://www.rfc-editor.org/info/rfc5480>.

   [RFC5652]  Housley, R., "Cryptographic Message Syntax (CMS)", STD 70,
              RFC 5652, DOI 10.17487/RFC5652, September 2009,
              <https://www.rfc-editor.org/info/rfc5652>.

   [RFC5869]  Krawczyk, H. and P. Eronen, "HMAC-based Extract-and-Expand
              Key Derivation Function (HKDF)", RFC 5869,
              DOI 10.17487/RFC5869, May 2010,
              <https://www.rfc-editor.org/info/rfc5869>.

   [RFC5912]  Hoffman, P. and J. Schaad, "New ASN.1 Modules for the
              Public Key Infrastructure Using X.509 (PKIX)", RFC 5912,
              DOI 10.17487/RFC5912, June 2010,
              <https://www.rfc-editor.org/info/rfc5912>.

   [RFC8017]  Moriarty, K., Ed., Kaliski, B., Jonsson, J., and A. Rusch,
              "PKCS #1: RSA Cryptography Specifications Version 2.2",
              RFC 8017, DOI 10.17487/RFC8017, November 2016,
              <https://www.rfc-editor.org/info/rfc8017>.

   [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/info/rfc8174>.

   [SHA3]     National Institute of Standards and Technology, "SHA-3
              Standard: Permutation-Based Hash and Extendable-Output
              Functions", NIST FIPS 202, DOI 10.6028/NIST.FIPS.202,
              August 2015,
              <http://nvlpubs.nist.gov/nistpubs/FIPS/NIST.FIPS.202.pdf>.

   [X.680]    ITU-T, "Information technology - Abstract Syntax Notation
              One (ASN.1): Specification of basic notation", ITU-T
              Recommendation X.680, ISO/IEC 8824-1:2021, February 2021,
              <https://www.itu.int/rec/T-REC-X.680-202102-I/en>.

   [X.690]    ITU-T, "Information technology - ASN.1 encoding rules:
              Specification of Basic Encoding Rules (BER), Canonical
              Encoding Rules (CER) and Distinguished Encoding Rules
              (DER)", ITU-T Recommendation X.690, ISO/IEC 8825-1:2021,
              February 2021,
              <https://www.itu.int/rec/T-REC-X.690-202102-I/en>.

8.2.  Informative References

   [IANA-ALG] IANA, "SMI Security for S/MIME Algorithms
              (1.2.840.113549.1.9.16.3)",
              <https://www.iana.org/assignments/smi-numbers/>.

   [IANA-MOD] IANA, "SMI Security for S/MIME Module Identifier
              (1.2.840.113549.1.9.16.0)",
              <https://www.iana.org/assignments/smi-numbers/>.

   [RFC4086]  Eastlake 3rd, D., Schiller, J., and S. Crocker,
              "Randomness Requirements for Security", BCP 106, RFC 4086,
              DOI 10.17487/RFC4086, June 2005,
              <https://www.rfc-editor.org/info/rfc4086>.

   [RFC8702]  Kampanakis, P. and Q. Dang, "Use of the SHAKE One-Way Hash
              Functions in the Cryptographic Message Syntax (CMS)",
              RFC 8702, DOI 10.17487/RFC8702, January 2020,
              <https://www.rfc-editor.org/info/rfc8702>.

   [RFC9629]  Housley, R., Gray, J., and T. Okubo, "Using Key
              Encapsulation Mechanism (KEM) Algorithms in the
              Cryptographic Message Syntax (CMS)", RFC 9629,
              DOI 10.17487/RFC9629, August 2024,
              <https://www.rfc-editor.org/info/rfc9629>.

Appendix A.  ASN.1 Module

   This section contains the ASN.1 module for the algorithm identifiers
   using the SHA3 family of hash functions [SHA3].  This module imports
   types from other ASN.1 modules that are defined in [RFC5912].

   <CODE BEGINS>
      SHA3-OIDs-2023
        { iso(1) member-body(2) us(840) rsadsi(113549) pkcs(1) pkcs-9(9)
          smime(16) modules(0) id-mod-sha3-oids-2023(78) }

      DEFINITIONS IMPLICIT TAGS ::=
      BEGIN

      EXPORTS ALL;

      IMPORTS

        AlgorithmIdentifier{}, DIGEST-ALGORITHM, SIGNATURE-ALGORITHM,
        KEY-DERIVATION, MAC-ALGORITHM
        FROM AlgorithmInformation-2009  -- [RFC5912]
          { iso(1) identified-organization(3) dod(6) internet(1)
            security(5) mechanisms(5) pkix(7) id-mod(0)
            id-mod-algorithmInformation-02(58) }

       mda-sha1, pk-rsa, pk-ec, ECDSA-Sig-Value
       FROM PKIXAlgs-2009  -- [RFC5912]
         { iso(1) identified-organization(3) dod(6) internet(1)
           security(5) mechanisms(5) pkix(7) id-mod(0)
           id-mod-pkix1-algorithms2008-02(56) }

       mda-sha224, mda-sha256, mda-sha384, mda-sha512
       FROM PKIX1-PSS-OAEP-Algorithms-2009  -- [RFC5912]
         { iso(1) identified-organization(3) dod(6) internet(1)
           security(5) mechanisms(5) pkix(7) id-mod(0)
           id-mod-pkix1-rsa-pkalgs-02(54) } ;

      --
      -- Alias
      --

      OID ::= OBJECT IDENTIFIER

      --
      -- Object Identifier Arcs
      --

      nistAlgorithm OID ::= { joint-iso-itu-t(2) country(16)
          us(840) organization(1) gov(101) csor(3) 4 }

      hashAlgs OID ::= { nistAlgorithm 2 }

      sigAlgs OID ::= { nistAlgorithm 3 }

      x9-44 OID ::= { iso(1) identified-organization(3) tc68(133)
          country(16) x9(840) x9Standards(9) x9-44(44) }

      x9-44-components OID ::= { x9-44 components(1) }

      id-alg OID ::= { iso(1) member-body(2) us(840)
          rsadsi(113549) pkcs(1) pkcs-9(9) smime(16) 3 }

      --
      -- Message Digest Algorithms
      --

      id-sha3-224 OID ::= { hashAlgs 7 }

      id-sha3-256 OID ::= { hashAlgs 8 }

      id-sha3-384 OID ::= { hashAlgs 9 }

      id-sha3-512 OID ::= { hashAlgs 10 }

      mda-sha3-224 DIGEST-ALGORITHM ::= {
          IDENTIFIER id-sha3-224
          PARAMS ARE absent }

      mda-sha3-256 DIGEST-ALGORITHM ::= {
          IDENTIFIER id-sha3-256
          PARAMS ARE absent }

      mda-sha3-384 DIGEST-ALGORITHM ::= {
          IDENTIFIER id-sha3-384
          PARAMS ARE absent }

      mda-sha3-512 DIGEST-ALGORITHM ::= {
          IDENTIFIER id-sha3-512
          PARAMS ARE absent }

      HashAlgorithm ::= AlgorithmIdentifier{ DIGEST-ALGORITHM,
                            { HashAlgorithms } }

      HashAlgorithms DIGEST-ALGORITHM ::=  {
          mda-sha3-224 |
          mda-sha3-256 |
          mda-sha3-384 |
          mda-sha3-512,
          ... }

      --
      -- Signature Algorithms
      --

      id-rsassa-pkcs1-v1-5-with-sha3-224 OID ::= { sigAlgs 13 }

      id-rsassa-pkcs1-v1-5-with-sha3-256 OID ::= { sigAlgs 14 }

      id-rsassa-pkcs1-v1-5-with-sha3-384 OID ::= { sigAlgs 15 }

      id-rsassa-pkcs1-v1-5-with-sha3-512 OID ::= { sigAlgs 16 }

      id-ecdsa-with-sha3-224 OID ::= { sigAlgs 9 }

      id-ecdsa-with-sha3-256 OID ::= { sigAlgs 10 }

      id-ecdsa-with-sha3-384 OID ::= { sigAlgs 11 }

      id-ecdsa-with-sha3-512 OID ::= { sigAlgs 12 }

      sa-rsaWithSHA3-224 SIGNATURE-ALGORITHM ::= {
          IDENTIFIER id-rsassa-pkcs1-v1-5-with-sha3-224
          PARAMS TYPE NULL ARE required
          HASHES { mda-sha3-224 }
          PUBLIC-KEYS { pk-rsa }
          SMIME-CAPS {IDENTIFIED BY
              id-rsassa-pkcs1-v1-5-with-sha3-224 } }

      sa-rsaWithSHA3-256 SIGNATURE-ALGORITHM ::= {
          IDENTIFIER id-rsassa-pkcs1-v1-5-with-sha3-256
          PARAMS TYPE NULL ARE required
          HASHES { mda-sha3-256 }
          PUBLIC-KEYS { pk-rsa }
          SMIME-CAPS {IDENTIFIED BY
              id-rsassa-pkcs1-v1-5-with-sha3-256 } }

      sa-rsaWithSHA3-384 SIGNATURE-ALGORITHM ::= {
          IDENTIFIER id-rsassa-pkcs1-v1-5-with-sha3-384
          PARAMS TYPE NULL ARE required
          HASHES { mda-sha3-384 }
          PUBLIC-KEYS { pk-rsa }
          SMIME-CAPS {IDENTIFIED BY
              id-rsassa-pkcs1-v1-5-with-sha3-384 } }

      sa-rsaWithSHA3-512 SIGNATURE-ALGORITHM ::= {
          IDENTIFIER id-rsassa-pkcs1-v1-5-with-sha3-512
          PARAMS TYPE NULL ARE required
          HASHES { mda-sha3-512 }
          PUBLIC-KEYS { pk-rsa }
          SMIME-CAPS {IDENTIFIED BY
              id-rsassa-pkcs1-v1-5-with-sha3-512 } }

      sa-ecdsaWithSHA3-224 SIGNATURE-ALGORITHM ::= {
          IDENTIFIER id-ecdsa-with-sha3-224
          VALUE ECDSA-Sig-Value
          PARAMS ARE absent
          HASHES { mda-sha3-224 }
          PUBLIC-KEYS { pk-ec }
          SMIME-CAPS {IDENTIFIED BY id-ecdsa-with-sha3-224 } }

      sa-ecdsaWithSHA3-256 SIGNATURE-ALGORITHM ::= {
          IDENTIFIER id-ecdsa-with-sha3-256
          VALUE ECDSA-Sig-Value
          PARAMS ARE absent
          HASHES { mda-sha3-256 }
          PUBLIC-KEYS { pk-ec }
          SMIME-CAPS {IDENTIFIED BY id-ecdsa-with-sha3-256 } }

      sa-ecdsaWithSHA3-384 SIGNATURE-ALGORITHM ::= {
          IDENTIFIER id-ecdsa-with-sha3-384
          VALUE ECDSA-Sig-Value
          PARAMS ARE absent
          HASHES { mda-sha3-384 }
          PUBLIC-KEYS { pk-ec }
          SMIME-CAPS {IDENTIFIED BY id-ecdsa-with-sha3-384 } }

      sa-ecdsaWithSHA3-512 SIGNATURE-ALGORITHM ::= {
          IDENTIFIER id-ecdsa-with-sha3-512
          VALUE ECDSA-Sig-Value
          PARAMS ARE absent
          HASHES { mda-sha3-512 }
          PUBLIC-KEYS { pk-ec }
          SMIME-CAPS {IDENTIFIED BY id-ecdsa-with-sha3-512 } }

      SignatureAlg ::= AlgorithmIdentifier{ SIGNATURE-ALGORITHM,
                            { SignatureAlgs } }

      SignatureAlgs SIGNATURE-ALGORITHM ::= {
          sa-rsaWithSHA3-224 |
          sa-rsaWithSHA3-256 |
          sa-rsaWithSHA3-384 |
          sa-rsaWithSHA3-512 |
          sa-ecdsaWithSHA3-224 |
          sa-ecdsaWithSHA3-256 |
          sa-ecdsaWithSHA3-384 |
          sa-ecdsaWithSHA3-512,
          ... }

      --
      -- Message Authentication Codes
      --

      id-hmacWithSHA3-224 OID ::= { hashAlgs 13 }

      id-hmacWithSHA3-256 OID ::= { hashAlgs 14 }

      id-hmacWithSHA3-384 OID ::= { hashAlgs 15 }

      id-hmacWithSHA3-512 OID ::= { hashAlgs 16 }

      maca-hmacWithSHA3-224 MAC-ALGORITHM ::= {
          IDENTIFIER id-hmacWithSHA3-224
          PARAMS ARE absent
          IS-KEYED-MAC TRUE
          SMIME-CAPS {IDENTIFIED BY id-hmacWithSHA3-224 } }

      maca-hmacWithSHA3-256 MAC-ALGORITHM ::= {
          IDENTIFIER id-hmacWithSHA3-256
          PARAMS ARE absent
          IS-KEYED-MAC TRUE
          SMIME-CAPS {IDENTIFIED BY id-hmacWithSHA3-256 } }

      maca-hmacWithSHA3-384 MAC-ALGORITHM ::= {
          IDENTIFIER id-hmacWithSHA3-384
          PARAMS ARE absent
          IS-KEYED-MAC TRUE
          SMIME-CAPS {IDENTIFIED BY id-hmacWithSHA3-384 } }

      maca-hmacWithSHA3-512 MAC-ALGORITHM ::= {
          IDENTIFIER id-hmacWithSHA3-512
          PARAMS ARE absent
          IS-KEYED-MAC TRUE
          SMIME-CAPS {IDENTIFIED BY id-hmacWithSHA3-512 } }

      MACAlgorithm ::= AlgorithmIdentifier{ MAC-ALGORITHM,
                          { MACAlgorithms } }

      MACAlgorithms MAC-ALGORITHM ::= {
          maca-hmacWithSHA3-224 |
          maca-hmacWithSHA3-256 |
          maca-hmacWithSHA3-384 |
          maca-hmacWithSHA3-512,
          ... }

      --
      -- Key Derivation Algorithms
      --

      id-alg-hkdf-with-sha3-224 OID ::= { id-alg 32 }

      id-alg-hkdf-with-sha3-256 OID ::= { id-alg 33 }

      id-alg-hkdf-with-sha3-384 OID ::= { id-alg 34 }

      id-alg-hkdf-with-sha3-512 OID ::= { id-alg 35 }

      id-kmac128 OID ::= { hashAlgs 21 }

      id-kmac256  OID ::= { hashAlgs 22 }

      id-kdf-kdf2 OID ::= { x9-44-components kdf2(1) }

      id-kdf-kdf3 OID ::= { x9-44-components kdf3(2) }

      kda-hkdf-with-sha3-224 KEY-DERIVATION ::= {
          IDENTIFIER id-alg-hkdf-with-sha3-224
          PARAMS ARE absent
          -- No S/MIME caps defined -- }

      kda-hkdf-with-sha3-256 KEY-DERIVATION ::= {
          IDENTIFIER id-alg-hkdf-with-sha3-256
          PARAMS ARE absent
          -- No S/MIME caps defined -- }

      kda-hkdf-with-sha3-384 KEY-DERIVATION ::= {
          IDENTIFIER id-alg-hkdf-with-sha3-384
          PARAMS ARE absent
          -- No S/MIME caps defined -- }

      kda-hkdf-with-sha3-512 KEY-DERIVATION ::= {
          IDENTIFIER id-alg-hkdf-with-sha3-512
          PARAMS ARE absent
          -- No S/MIME caps defined -- }

      kda-kmac128 KEY-DERIVATION ::= {
          IDENTIFIER id-kmac128
          PARAMS TYPE Customization ARE optional
          -- PARAMS are absent when Customization is ''H --
          -- No S/MIME caps defined -- }

      kda-kmac256 KEY-DERIVATION ::= {
          IDENTIFIER id-kmac256
          PARAMS TYPE Customization ARE optional
          -- PARAMS are absent when Customization is ''H --
          -- No S/MIME caps defined -- }

      kda-kdf2 KEY-DERIVATION ::= {
          IDENTIFIER id-kdf-kdf2
          PARAMS TYPE KDF2-HashFunction ARE required
          -- No S/MIME caps defined -- }

      kda-kdf3 KEY-DERIVATION ::= {
          IDENTIFIER id-kdf-kdf3
          PARAMS TYPE KDF3-HashFunction ARE required
          -- No S/MIME caps defined -- }

      Customization ::= OCTET STRING

      KDF2-HashFunction ::= AlgorithmIdentifier { DIGEST-ALGORITHM,
                                { KDF2-HashFunctions } }

      KDF2-HashFunctions DIGEST-ALGORITHM ::= {
         X9-HashFunctions,
         ... }

      KDF3-HashFunction ::= AlgorithmIdentifier { DIGEST-ALGORITHM,
                                { KDF3-HashFunctions } }

      KDF3-HashFunctions DIGEST-ALGORITHM ::= {
         X9-HashFunctions,
         ... }

      X9-HashFunctions DIGEST-ALGORITHM ::= {
          mda-sha1 |
          mda-sha224 |
          mda-sha256 |
          mda-sha384 |
          mda-sha512 |
          mda-sha3-224 |
          mda-sha3-256 |
          mda-sha3-384 |
          mda-sha3-512,
          ... }

      KeyDerivationFunction ::=  AlgorithmIdentifier{ KEY-DERIVATION,
                                     { KeyDevAlgs } }

      KeyDevAlgs KEY-DERIVATION ::= {
          kda-hkdf-with-sha3-224 |
          kda-hkdf-with-sha3-256 |
          kda-hkdf-with-sha3-384 |
          kda-hkdf-with-sha3-512 |
          kda-kmac128 |
          kda-kmac256 |
          kda-kdf2 |
          kda-kdf3,
          ... }

      END
   <CODE ENDS>

Acknowledgements

   Thanks to Daniel Van Geest and Sean Turner for their careful review
   and thoughtful comments.

   Thanks to Sara Kerman, Quynh Dang, and David Cooper for getting the
   object identifiers assigned for KMAC128 and KMAC256.

Author's Address

   Russ Housley
   Vigil Security, LLC
   Herndon, VA
   United States of America
   Email: housley@vigilsec.com