Certificate Management Protocol (CMP) Algorithms
draft-ietf-lamps-cmp-algorithms-15
| Document | Type | Active Internet-Draft (lamps WG) | |
|---|---|---|---|
| Authors | Hendrik Brockhaus , Hans Aschauer , Mike Ounsworth , John Gray | ||
| Last updated | 2023-05-30 (Latest revision 2022-06-02) | ||
| RFC stream | Internet Engineering Task Force (IETF) | ||
| Intended RFC status | Proposed Standard | ||
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| Additional resources | Mailing list discussion | ||
| Stream | WG state | Submitted to IESG for Publication | |
| Associated WG milestone |
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| Document shepherd | Russ Housley | ||
| Shepherd write-up | Show Last changed 2021-10-06 | ||
| IESG | IESG state | RFC Ed Queue | |
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| Consensus boilerplate | Yes | ||
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| Responsible AD | Roman Danyliw | ||
| Send notices to | housley@vigilsec.com | ||
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| RFC Editor | RFC Editor state | EDIT | |
| Details |
draft-ietf-lamps-cmp-algorithms-15
LAMPS Working Group H. Brockhaus, Ed.
Internet-Draft H. Aschauer
Updates: 4210 (if approved) Siemens
Intended status: Standards Track M. Ounsworth
Expires: 4 December 2022 J. Gray
Entrust
2 June 2022
Certificate Management Protocol (CMP) Algorithms
draft-ietf-lamps-cmp-algorithms-15
Abstract
This document describes the conventions for using several
cryptographic algorithms with the Certificate Management Protocol
(CMP). CMP is used to enroll and further manage the lifecycle of
X.509 certificates. This document also updates the algorithm use
profile from RFC 4210 Appendix D.2.
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 4 December 2022.
Copyright Notice
Copyright (c) 2022 IETF Trust and the persons identified as the
document authors. All rights reserved.
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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.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 3
2. Message Digest Algorithms . . . . . . . . . . . . . . . . . . 3
2.1. SHA2 . . . . . . . . . . . . . . . . . . . . . . . . . . 4
2.2. SHAKE . . . . . . . . . . . . . . . . . . . . . . . . . . 4
3. Signature Algorithms . . . . . . . . . . . . . . . . . . . . 5
3.1. RSA . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
3.2. ECDSA . . . . . . . . . . . . . . . . . . . . . . . . . . 6
3.3. EdDSA . . . . . . . . . . . . . . . . . . . . . . . . . . 7
4. Key Management Algorithms . . . . . . . . . . . . . . . . . . 8
4.1. Key Agreement Algorithms . . . . . . . . . . . . . . . . 8
4.1.1. Diffie-Hellman . . . . . . . . . . . . . . . . . . . 8
4.1.2. ECDH . . . . . . . . . . . . . . . . . . . . . . . . 9
4.2. Key Transport Algorithms . . . . . . . . . . . . . . . . 10
4.2.1. RSA . . . . . . . . . . . . . . . . . . . . . . . . . 10
4.3. Symmetric Key-Encryption Algorithms . . . . . . . . . . . 11
4.3.1. AES Key Wrap . . . . . . . . . . . . . . . . . . . . 11
4.4. Key Derivation Algorithms . . . . . . . . . . . . . . . . 12
4.4.1. PBKDF2 . . . . . . . . . . . . . . . . . . . . . . . 12
5. Content Encryption Algorithms . . . . . . . . . . . . . . . . 13
5.1. AES-CBC . . . . . . . . . . . . . . . . . . . . . . . . . 13
6. Message Authentication Code Algorithms . . . . . . . . . . . 14
6.1. Password-Based MAC . . . . . . . . . . . . . . . . . . . 14
6.1.1. PasswordBasedMac . . . . . . . . . . . . . . . . . . 14
6.1.2. PBMAC1 . . . . . . . . . . . . . . . . . . . . . . . 15
6.2. Symmetric Key-Based MAC . . . . . . . . . . . . . . . . . 15
6.2.1. SHA2-Based HMAC . . . . . . . . . . . . . . . . . . . 15
6.2.2. AES-GMAC . . . . . . . . . . . . . . . . . . . . . . 16
6.2.3. SHAKE-Based KMAC . . . . . . . . . . . . . . . . . . 16
7. Algorithm Use Profiles . . . . . . . . . . . . . . . . . . . 17
7.1. Algorithm Profile for RFC 4210 PKI Management Message
Profiles . . . . . . . . . . . . . . . . . . . . . . . . 20
7.2. Algorithm Profile for Lightweight CMP Profile . . . . . . 22
8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 23
9. Security Considerations . . . . . . . . . . . . . . . . . . . 24
10. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 25
11. Normative References . . . . . . . . . . . . . . . . . . . . 25
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12. Informative References . . . . . . . . . . . . . . . . . . . 29
Appendix A. History of Changes . . . . . . . . . . . . . . . . . 29
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 32
1. Introduction
RFC 4210 Appendix D.2 [RFC4210] contains a set of algorithms,
mandatory to be supported by conforming implementations. These
algorithms were appropriate at the time CMP was released, but as
cryptographic algorithms weaken over time, some of them should not be
used anymore. In general, new attacks are emerging due to research
cryptoanalysis or increase in computing power. New algorithms were
introduced that are more resistant to today's attacks.
This document lists current cryptographic algorithms usable with CMP
to offer an easier way maintaining the list of suitable algorithms
over time.
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 BCP
14 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here.
In the following sections ASN.1 values and types are used to indicate
where algorithm identifier and output values are provided. These
ASN.1 values and types are defined in CMP [RFC4210], CRMF [RFC4211],
CMP Updates [I-D.ietf-lamps-cmp-updates], or CMS [RFC5652].
2. Message Digest Algorithms
This section provides references to object identifiers and
conventions to be employed by CMP implementations that support SHA2
or SHAKE message digest algorithms.
Digest algorithm identifiers are located in:
* hashAlg field of OOBCertHash and CertStatus
* owf field of Challenge, PBMParameter, and DHBMParameter
* digestAlgorithms field of SignedData
* digestAlgorithm field of SignerInfo
Digest values are located in:
* hashVal field of OOBCertHash
* certHash field of CertStatus
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* witness field of Challenge
In addition, digest values are input to signature algorithms.
2.1. SHA2
The SHA2 algorithm family is defined in FIPS Pub 180-4
[NIST.FIPS.180-4].
The message digest algorithms SHA-224, SHA-256, SHA-384, and SHA-512
are identified by the following OIDs:
id-sha224 OBJECT IDENTIFIER ::= { joint-iso-itu-t(2) country(16)
us(840) organization(1) gov(101) csor(3) nistalgorithm(4)
hashalgs(2) 4 }
id-sha256 OBJECT IDENTIFIER ::= { joint-iso-itu-t(2) country(16)
us(840) organization(1) gov(101) csor(3) nistalgorithm(4)
hashalgs(2) 1 }
id-sha384 OBJECT IDENTIFIER ::= { joint-iso-itu-t(2) country(16)
us(840) organization(1) gov(101) csor(3) nistalgorithm(4)
hashalgs(2) 2 }
id-sha512 OBJECT IDENTIFIER ::= { joint-iso-itu-t(2) country(16)
us(840) organization(1) gov(101) csor(3) nistalgorithm(4)
hashalgs(2) 3 }
Specific conventions to be considered are specified in RFC 5754
Section 2 [RFC5754].
2.2. SHAKE
The SHA-3 family of hash functions is defined in FIPS Pub 202
[NIST.FIPS.202] and includes fixed output length variants SHA3-224,
SHA3-256, SHA3-384, and SHA3-512, as well as extendable-output
functions (SHAKEs) SHAKE128 and SHAKE256. Currently, SHAKE128 and
SHAKE256 are the only members of the SHA3-family which are specified
for use in X.509 certificates [RFC8692] and CMS [RFC8702] as one-way
hash function for use with RSASSA-PSS and ECDSA.
SHAKE is an extendable-output function and FIPS Pub 202
[NIST.FIPS.202] prohibits using SHAKE as general-purpose hash
function. When SHAKE is used in CMP as a message digest algorithm,
the output length MUST be 256 bits for SHAKE128 and 512 bits for
SHAKE256.
The message digest algorithms SHAKE128 and SHAKE256 are identified by
the following OIDs:
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id-shake128 OBJECT IDENTIFIER ::= { joint-iso-itu-t(2) country(16)
us(840) organization(1) gov(101) csor(3) nistAlgorithm(4)
hashalgs(2) 11 }
id-shake256 OBJECT IDENTIFIER ::= { joint-iso-itu-t(2) country(16)
us(840) organization(1) gov(101) csor(3) nistAlgorithm(4)
hashalgs(2) 12 }
Specific conventions to be considered are specified in RFC 8702
Section 3.1 [RFC8702].
3. Signature Algorithms
This section provides references to object identifiers and
conventions to be employed by CMP implementations that support RSA,
ECDSA, or EdDSA signature algorithms.
The signature algorithm is referred to as MSG_SIG_ALG in Section 7.2,
RFC 4210 Appendix D and E [RFC4210], and in the Lightweight CMP
Profile [I-D.ietf-lamps-lightweight-cmp-profile].
Signature algorithm identifiers are located in:
* protectionAlg field of PKIHeader
* algorithmIdentifier field of POPOSigningKey
* signatureAlgorithm field of CertificationRequest,
SignKeyPairTypes, and SignerInfo
Signature values are located in:
* protection field of PKIMessage
* signature field of POPOSigningKey
* signature field of CertificationRequest and SignerInfo
3.1. RSA
The RSA (RSASSA-PSS and PKCS#1 version 1.5) signature algorithm is
defined in RFC 8017 [RFC8017].
The algorithm identifier for RSASAA-PSS signatures used with SHA2
message digest algorithms is identified by the following OID:
id-RSASSA-PSS OBJECT IDENTIFIER ::= { iso(1) member-body(2)
us(840) rsadsi(113549) pkcs(1) pkcs-1(1) 10 }
Specific conventions to be considered are specified in RFC 4056
[RFC4056].
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The signature algorithm RSASSA-PSS used with SHAKE message digest
algorithms are identified by the following OIDs:
id-RSASSA-PSS-SHAKE128 OBJECT IDENTIFIER ::= { iso(1)
identified-organization(3) dod(6) internet(1) security(5)
mechanisms(5) pkix(7) algorithms(6) 30 }
id-RSASSA-PSS-SHAKE256 OBJECT IDENTIFIER ::= { iso(1)
identified-organization(3) dod(6) internet(1) security(5)
mechanisms(5) pkix(7) algorithms(6) 31 }
Specific conventions to be considered are specified in RFC 8702
Section 3.2.1 [RFC8702].
The signature algorithm PKCS#1 version 1.5 used with SHA2 message
digest algorithms is identified by the following OIDs:
sha224WithRSAEncryption OBJECT IDENTIFIER ::= { iso(1)
member-body(2) us(840) rsadsi(113549) pkcs(1) pkcs-1(1) 14 }
sha256WithRSAEncryption OBJECT IDENTIFIER ::= { iso(1)
member-body(2) us(840) rsadsi(113549) pkcs(1) pkcs-1(1) 11 }
sha384WithRSAEncryption OBJECT IDENTIFIER ::= { iso(1)
member-body(2) us(840) rsadsi(113549) pkcs(1) pkcs-1(1) 12 }
sha512WithRSAEncryption OBJECT IDENTIFIER ::= { iso(1)
member-body(2) us(840) rsadsi(113549) pkcs(1) pkcs-1(1) 13 }
Specific conventions to be considered are specified in RFC 5754
Section 3.2 [RFC5754].
3.2. ECDSA
The ECDSA signature algorithm is defined in FIPS Pub 186-4
[NIST.FIPS.186-4].
The signature algorithm ECDSA used with SHA2 message digest
algorithms is identified by the following OIDs:
ecdsa-with-SHA224 OBJECT IDENTIFIER ::= { iso(1) member-body(2)
us(840) ansi-X9-62(10045) signatures(4) ecdsa-with-SHA2(3) 1 }
ecdsa-with-SHA256 OBJECT IDENTIFIER ::= { iso(1) member-body(2)
us(840) ansi-X9-62(10045) signatures(4) ecdsa-with-SHA2(3) 2 }
ecdsa-with-SHA384 OBJECT IDENTIFIER ::= { iso(1) member-body(2)
us(840) ansi-X9-62(10045) signatures(4) ecdsa-with-SHA2(3) 3 }
ecdsa-with-SHA512 OBJECT IDENTIFIER ::= { iso(1) member-body(2)
us(840) ansi-X9-62(10045) signatures(4) ecdsa-with-SHA2(3) 4 }
As specified in RFC 5480 [RFC5480] the NIST-recommended SECP curves
are identified by the following OIDs:
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secp192r1 OBJECT IDENTIFIER ::= { iso(1) member-body(2)
us(840) ansi-X9-62(10045) curves(3) prime(1) 1 }
secp224r1 OBJECT IDENTIFIER ::= { iso(1)
identified-organization(3) certicom(132) curve(0) 33 }
secp256r1 OBJECT IDENTIFIER ::= { iso(1) member-body(2)
us(840) ansi-X9-62(10045) curves(3) prime(1) 7 }
secp384r1 OBJECT IDENTIFIER ::= { iso(1)
identified-organization(3) certicom(132) curve(0) 34 }
secp521r1 OBJECT IDENTIFIER ::= { iso(1)
identified-organization(3) certicom(132) curve(0) 35 }
Specific conventions to be considered are specified in RFC 5754
Section 3.3 [RFC5754].
The signature algorithm ECDSA used with SHAKE message digest
algorithms are identified by the following OIDs:
id-ecdsa-with-shake128 OBJECT IDENTIFIER ::= { iso(1)
identified-organization(3) dod(6) internet(1) security(5)
mechanisms(5) pkix(7) algorithms(6) 32 }
id-ecdsa-with-shake256 OBJECT IDENTIFIER ::= { iso(1)
identified-organization(3) dod(6) internet(1) security(5)
mechanisms(5) pkix(7) algorithms(6) 33 }
Specific conventions to be considered are specified in RFC 8702
Section 3.2.2 [RFC8702].
3.3. EdDSA
The EdDSA signature algorithm is defined in RFC 8032 Section 3.3
[RFC8032] and FIPS Pub 186-5 (Draft) [NIST.FIPS.186-5].
The signature algorithm Ed25519 that MUST be used with SHA-512
message digest algorithms is identified by the following OIDs:
id-Ed25519 OBJECT IDENTIFIER ::= { iso(1)
identified-organization(3) thawte(101) 112 }
The signature algorithm Ed448 that MUST be used with SHAKE256 message
digest algorithms is identified by the following OIDs:
id-Ed448 OBJECT IDENTIFIER ::= { iso(1)
identified-organization(3) thawte(101) 113 }
Specific conventions to be considered are specified in RFC 8419
[RFC8419].
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Note: The hash algorithm used to calculate the certHash in certConf
messages MUST be SHA512 if the certificate to be confirmed has been
signed using Ed25519 and SHAKE256 with d=512 if signed using Ed448.
4. Key Management Algorithms
CMP utilizes the following general key management techniques: key
agreement, key transport, and passwords.
CRMF [RFC4211] and CMP Updates [I-D.ietf-lamps-cmp-updates] promotes
the use of CMS [RFC5652] EnvelopedData by deprecating the use of
EncryptedValue.
4.1. Key Agreement Algorithms
The key agreement algorithm is referred to as PROT_ENC_ALG in
RFC 4210 Appendix D and E [RFC4210] and as KM_KA_ALG in the
Lightweight CMP Profile [I-D.ietf-lamps-lightweight-cmp-profile], as
well as in Section 7.
Key agreement algorithms are only used in CMP when using CMS
[RFC5652] EnvelopedData together with the key agreement key
management technique. When a key agreement algorithm is used, a key-
encryption algorithm (Section 4.3) is needed next to the content-
encryption algorithm (Section 5).
Key agreement algorithm identifiers are located in:
* keyEncryptionAlgorithm field of KeyAgreeRecipientInfo
Key wrap algorithm identifiers are located in:
* KeyWrapAlgorithm parameters within keyEncryptionAlgorithm field of
KeyAgreeRecipientInfo
Wrapped content-encryption keys are located in:
* encryptedKey field of RecipientEncryptedKeys
4.1.1. Diffie-Hellman
Diffie-Hellman key agreement is defined in RFC 2631 [RFC2631] and
SHALL be used in the ephemeral-static as specified in RFC 3370
[RFC3370]. Static-static variants SHALL NOT be used.
The Diffie-Hellman key agreement algorithm is identified by the
following OID:
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id-alg-ESDH OBJECT IDENTIFIER ::= { iso(1) member-body(2)
us(840) rsadsi(113549) pkcs(1) pkcs-9(9) smime(16) alg(3) 5 }
Specific conventions to be considered are specified in RFC 3370
Section 4.1 [RFC3370].
4.1.2. ECDH
Elliptic Curve Diffie-Hellman (ECDH) key agreement is defined in
RFC 5753 [RFC5753] and SHALL be used in the ephemeral-static variant
as specified in RFC 5753 [RFC5753] or the 1-Pass ECMQV variant as
specified in RFC 5753 [RFC5753]. Static-static variants SHALL NOT be
used.
The ECDH key agreement algorithm used together with NIST-recommended
SECP curves are identified by the following OIDs:
dhSinglePass-stdDH-sha224kdf-scheme OBJECT IDENTIFIER ::= { iso(1)
identified-organization(3) certicom(132) schemes(1) 11(11) 0 }
dhSinglePass-stdDH-sha256kdf-scheme OBJECT IDENTIFIER ::= { iso(1)
identified-organization(3) certicom(132) schemes(1) 11(11) 1 }
dhSinglePass-stdDH-sha384kdf-scheme OBJECT IDENTIFIER ::= { iso(1)
identified-organization(3) certicom(132) schemes(1) 11(11) 2 }
dhSinglePass-stdDH-sha512kdf-scheme OBJECT IDENTIFIER ::= { iso(1)
identified-organization(3) certicom(132) schemes(1) 11(11) 3 }
dhSinglePass-cofactorDH-sha224kdf-scheme OBJECT IDENTIFIER ::= {
iso(1) identified-organization(3) certicom(132) schemes(1)
14(14) 0 }
dhSinglePass-cofactorDH-sha256kdf-scheme OBJECT IDENTIFIER ::= {
iso(1) identified-organization(3) certicom(132) schemes(1)
14(14) 1 }
dhSinglePass-cofactorDH-sha384kdf-scheme OBJECT IDENTIFIER ::= {
iso(1) identified-organization(3) certicom(132) schemes(1)
14(14) 2 }
dhSinglePass-cofactorDH-sha512kdf-scheme OBJECT IDENTIFIER ::= {
iso(1) identified-organization(3) certicom(132) schemes(1)
14(14) 3 }
mqvSinglePass-sha224kdf-scheme OBJECT IDENTIFIER ::= { iso(1)
identified-organization(3) certicom(132) schemes(1) 15(15) 0 }
mqvSinglePass-sha256kdf-scheme OBJECT IDENTIFIER ::= { iso(1)
identified-organization(3) certicom(132) schemes(1) 15(15) 1 }
mqvSinglePass-sha384kdf-scheme OBJECT IDENTIFIER ::= { iso(1)
identified-organization(3) certicom(132) schemes(1) 15(15) 2 }
mqvSinglePass-sha512kdf-scheme OBJECT IDENTIFIER ::= { iso(1)
identified-organization(3) certicom(132) schemes(1) 15(15) 3 }
As specified in RFC 5480 [RFC5480] the NIST-recommended SECP curves
are identified by the following OIDs:
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secp192r1 OBJECT IDENTIFIER ::= { iso(1) member-body(2)
us(840) ansi-X9-62(10045) curves(3) prime(1) 1 }
secp224r1 OBJECT IDENTIFIER ::= { iso(1)
identified-organization(3) certicom(132) curve(0) 33 }
secp256r1 OBJECT IDENTIFIER ::= { iso(1) member-body(2)
us(840) ansi-X9-62(10045) curves(3) prime(1) 7 }
secp384r1 OBJECT IDENTIFIER ::= { iso(1)
identified-organization(3) certicom(132) curve(0) 34 }
secp521r1 OBJECT IDENTIFIER ::= { iso(1)
identified-organization(3) certicom(132) curve(0) 35 }
Specific conventions to be considered are specified in RFC 5753
[RFC5753].
The ECDH key agreement algorithm used together with curve25519 or
curve448 are identified by the following OIDs:
id-X25519 OBJECT IDENTIFIER ::= { iso(1)
identified-organization(3) thawte(101) 110 }
id-X448 OBJECT IDENTIFIER ::= { iso(1)
identified-organization(3) thawte(101) 111 }
Specific conventions to be considered are specified in RFC 8418
[RFC8418].
4.2. Key Transport Algorithms
The key transport algorithm is also referred to as PROT_ENC_ALG in
RFC 4210 Appendix D and E [RFC4210] and as KM_KL_ALG in the
Lightweight CMP Profile [I-D.ietf-lamps-lightweight-cmp-profile], as
well as in Section 7.
Key transport algorithms are only used in CMP when using CMS
[RFC5652] EnvelopedData together with the key transport key
management technique.
Key transport algorithm identifiers are located in:
* keyEncryptionAlgorithm field of KeyTransRecipientInfo
Key transport encrypted content-encryption keys are located in:
* encryptedKey field of KeyTransRecipientInfo
4.2.1. RSA
The RSA key transport algorithm is the RSA encryption scheme defined
in RFC 8017 [RFC8017].
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The algorithm identifier for RSA (PKCS #1 v1.5) is:
rsaEncryption OBJECT IDENTIFIER ::= { iso(1) member-body(2)
us(840) rsadsi(113549) pkcs(1) pkcs-1(1) 1 }
The algorithm identifier for RSAES-OAEP is:
id-RSAES-OAEP OBJECT IDENTIFIER ::= { iso(1) member-body(2)
us(840) rsadsi(113549) pkcs(1) pkcs-1(1) 7 }
Further conventions to be considered for PKCS #1 v1.5 are specified
in RFC 3370 Section 4.2.1 [RFC3370] and for RSAES-OAEP in RFC 3560
[RFC3560].
4.3. Symmetric Key-Encryption Algorithms
The symmetric key-encryption algorithm is also referred to as
KM_KW_ALG in Section 7.2 and in the Lightweight CMP Profile
[I-D.ietf-lamps-lightweight-cmp-profile].
As symmetric key-encryption key management technique is not used by
CMP, the symmetric key-encryption algorithm is only needed when using
the key agreement or password-based key management technique with CMS
[RFC5652] EnvelopedData.
Key wrap algorithm identifiers are located in:
* parameters field of the KeyEncryptionAlgorithmIdentifier of
KeyAgreeRecipientInfo and PasswordRecipientInfo
Wrapped content-encryption keys are located in:
* encryptedKey field of RecipientEncryptedKeys (for key agreement)
and PasswordRecipientInfo (for password-based key management)
4.3.1. AES Key Wrap
The AES encryption algorithm is defined in FIPS Pub 197
[NIST.FIPS.197] and the key wrapping is defined in RFC 3394
[RFC3394].
AES key encryption has the algorithm identifier:
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id-aes128-wrap OBJECT IDENTIFIER ::= { joint-iso-itu-t(2)
country(16) us(840) organization(1) gov(101) csor(3)
nistAlgorithm(4) aes(1) 5 }
id-aes192-wrap OBJECT IDENTIFIER ::= { joint-iso-itu-t(2)
country(16) us(840) organization(1) gov(101) csor(3)
nistAlgorithm(4) aes(1) 25 }
id-aes256-wrap OBJECT IDENTIFIER ::= { joint-iso-itu-t(2)
country(16) us(840) organization(1) gov(101) csor(3)
nistAlgorithm(4) aes(1) 45 }
The underlying encryption functions for the key wrap and content-
encryption algorithms (as specified in Section 5) and the key sizes
for the two algorithms MUST be the same (e.g., AES-128 key wrap
algorithm with AES-128 content-encryption algorithm), see also
RFC 8551 [RFC8551].
Further conventions to be considered for AES key wrap are specified
in RFC 3394 Section 2.2 [RFC3394] and RFC 3565 Section 2.3.2
[RFC3565].
4.4. Key Derivation Algorithms
The key derivation algorithm is also referred to as KM_KD_ALG in
Section 7.2 and in the Lightweight CMP Profile
[I-D.ietf-lamps-lightweight-cmp-profile].
Key derivation algorithms are only used in CMP when using CMS
[RFC5652] EnvelopedData together with password-based key management
technique.
Key derivation algorithm identifiers are located in:
* keyDerivationAlgorithm field of PasswordRecipientInfo
When using the password-based key management technique with
EnvelopedData as specified in CMP Updates together with message
authentication code (MAC)-based PKIProtection, the salt for the
password-based MAC and KDF must be chosen independently to ensure
usage of independent symmetric keys.
4.4.1. PBKDF2
The password-based key derivation function 2 (PBKDF2) is defined in
RFC 8018 [RFC8018].
Password-based key derivation function 2 has the algorithm
identifier:
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id-PBKDF2 OBJECT IDENTIFIER ::= { iso(1) member-body(2) us(840)
rsadsi(113549) pkcs(1) pkcs-5(5) 12 }
Further conventions to be considered for PBKDF2 are specified in
RFC 3370 Section 4.4.1 [RFC3370] and RFC 8018 Section 5.2 [RFC8018].
5. Content Encryption Algorithms
The content encryption algorithm is also referred to as PROT_SYM_ALG
in Section 7, RFC 4210 Appendix D and E [RFC4210], and the
Lightweight CMP Profile [I-D.ietf-lamps-lightweight-cmp-profile].
Content encryption algorithms are only used in CMP when using CMS
[RFC5652] EnvelopedData to transport a signed private key package in
case of central key generation or key archiving, a certificate to
facilitate implicit proof-of-possession, or a revocation passphrase
in encrypted form.
Content encryption algorithm identifiers are located in:
* contentEncryptionAlgorithm field of EncryptedContentInfo
Encrypted content is located in:
* encryptedContent field of EncryptedContentInfo
5.1. AES-CBC
The AES encryption algorithm is defined in FIPS Pub 197
[NIST.FIPS.197].
AES-CBC content encryption has the algorithm identifier:
id-aes128-CBC OBJECT IDENTIFIER ::= { joint-iso-itu-t(2)
country(16) us(840) organization(1) gov(101) csor(3)
nistAlgorithm(4) aes(1) 2 }
id-aes192-CBC OBJECT IDENTIFIER ::= { joint-iso-itu-t(2)
country(16) us(840) organization(1) gov(101) csor(3)
nistAlgorithm(4) aes(1)22 }
id-aes256-CBC OBJECT IDENTIFIER ::= { joint-iso-itu-t(2)
country(16) us(840) organization(1) gov(101) csor(3)
nistAlgorithm(4) aes(1)42 }
Specific conventions to be considered for AES-CBC content encryption
are specified in RFC 3565 [RFC3565].
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6. Message Authentication Code Algorithms
The message authentication code (MAC) is either used for shared
secret-based CMP message protection or together with the password-
based key derivation function (PBKDF2).
The message authentication code algorithm is also referred to as
MSG_MAC_ALG in Section 7, RFC 4210 Appendix D and E [RFC4210], and
the Lightweight CMP Profile [I-D.ietf-lamps-lightweight-cmp-profile].
6.1. Password-Based MAC
Password-based message authentication code (MAC) algorithms combine
the derivation of a symmetric key from a password or other shared
secret information and a symmetric key-based MAC function as
specified in Section 6.2 using this derived key.
Message authentication code algorithm identifiers are located in:
* protectionAlg field of PKIHeader
Message authentication code values are located in:
* PKIProtection field of PKIMessage
6.1.1. PasswordBasedMac
The PasswordBasedMac algorithm is defined in RFC 4210 Section 5.1.3.1
[RFC4210], RFC 4211 Section 4.4 [RFC4211], and Algorithm Requirements
Update to the Internet X.509 Public Key Infrastructure Certificate
Request Message Format (CRMF) [RFC9045].
The PasswordBasedMac algorithm is identified by the following OID:
id-PasswordBasedMac OBJECT IDENTIFIER ::= { iso(1) member-body(2)
us(840) nt(113533) nsn(7) algorithms(66) 13 }
Further conventions to be considered for password-based MAC are
specified in RFC 4210 Section 5.1.3.1 [RFC4210], RFC 4211 Section 4.4
[RFC4211], and Algorithm Requirements Update to the Internet X.509
Public Key Infrastructure Certificate Request Message Format (CRMF)
[RFC9045].
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6.1.2. PBMAC1
The Password-Based Message Authentication Code 1 (PBMAC1) is defined
in RFC 8018 [RFC8018]. PBMAC1 combines a password-based key
derivation function like PBKDF2 (Section 4.4.1) with an underlying
symmetric key-based message authentication scheme.
PBMAC1 has the following OID:
id-PBMAC1 OBJECT IDENTIFIER ::= { iso(1) member-body(2) us(840)
rsadsi(113549) pkcs(1) pkcs-5(5) 14 }
Specific conventions to be considered for PBMAC1 are specified in
RFC 8018 Section 7.1 and A.5 [RFC8018].
6.2. Symmetric Key-Based MAC
Symmetric key-based message authentication code (MAC) algorithms are
used for deriving the symmetric encryption key when using PBKDF2 as
described in Section 4.4.1 as well as with Password-based MAC as
described in Section 6.1.
Message authentication code algorithm identifiers are located in:
* protectionAlg field of PKIHeader
* messageAuthScheme field of PBMAC1
* mac field of PBMParameter
* prf field of PBKDF2-params
Message authentication code values are located in:
* PKIProtection field of PKIMessage
6.2.1. SHA2-Based HMAC
The HMAC algorithm is defined in RFC 2104 [RFC2104] and
FIPS Pub 198-1 [NIST.FIPS.198-1].
The HMAC algorithm used with SHA2 message digest algorithms is
identified by the following OIDs:
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id-hmacWithSHA224 OBJECT IDENTIFIER ::= { iso(1) member-body(2)
us(840) rsadsi(113549) digestAlgorithm(2) 8 }
id-hmacWithSHA256 OBJECT IDENTIFIER ::= { iso(1) member-body(2)
us(840) rsadsi(113549) digestAlgorithm(2) 9 }
id-hmacWithSHA384 OBJECT IDENTIFIER ::= { iso(1) member-body(2)
us(840) rsadsi(113549) digestAlgorithm(2) 10 }
id-hmacWithSHA512 OBJECT IDENTIFIER ::= { iso(1) member-body(2)
us(840) rsadsi(113549) digestAlgorithm(2) 11 }
Specific conventions to be considered for SHA2-based HMAC are
specified in RFC 4231 Section 3.1 [RFC4231].
6.2.2. AES-GMAC
The AES-GMAC algorithm is defined in FIPS Pub 197 [NIST.FIPS.197] and
NIST SP 800-38d [NIST.SP.800-38d].
Note: AES-GMAC MUST NOT be used twice with the same parameter set,
especially the same nonce. Therefore, it MUST NOT be used together
with PBKDF2. When using it with PBMAC1 it MUST be ensured that AES-
GMAC is only used as message authentication scheme and not for the
key derivation function PBKDF2.
The AES-GMAC algorithm is identified by the following OIDs:
id-aes128-GMAC OBJECT IDENTIFIER ::= { joint-iso-itu-t(2)
country(16) us(840) organization(1) gov(101) csor(3)
nistAlgorithm(4) aes(1) 9 }
id-aes192-GMAC OBJECT IDENTIFIER ::= { joint-iso-itu-t(2)
country(16) us(840) organization(1) gov(101) csor(3)
nistAlgorithm(4) aes(1) 29 }
id-aes256-GMAC OBJECT IDENTIFIER ::= { joint-iso-itu-t(2)
country(16) us(840) organization(1) gov(101) csor(3)
nistAlgorithm(4) aes(1) 49 }
Specific conventions to be considered for AES-GMAC are specified in
RFC 9044 [RFC9044].
6.2.3. SHAKE-Based KMAC
The KMAC algorithm is defined in RFC 8702 [RFC8702] and
FIPS SP 800-185 [NIST.SP.800-185].
The SHAKE-based KMAC algorithm is identified by the following OIDs:
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id-KmacWithSHAKE128 OBJECT IDENTIFIER ::= { joint-iso-itu-t(2)
country(16) us(840) organization(1) gov(101) csor(3)
nistAlgorithm(4) 2 19 }
id-KmacWithSHAKE256 OBJECT IDENTIFIER ::= { joint-iso-itu-t(2)
country(16) us(840) organization(1) gov(101) csor(3)
nistAlgorithm(4) 2 20 }
Specific conventions to be considered for KMAC with SHAKE are
specified in RFC 8702 Section 3.4 [RFC8702].
7. Algorithm Use Profiles
This section provides profiles of algorithms and respective
conventions for different application use cases.
Recommendations like NIST SP 800-57 Recommendation for Key Management
Table 2 [NIST.SP.800-57pt1r5] and ECRYPT Algorithms, Key Size and
Protocols Report (2018) Section 4.6 [ECRYPT.CSA.D5.4] provide general
information on current cryptographic algorithms.
The overall cryptographic strength of a CMP deployment will depend on
several factors, including:
* Capabilities of the end entity: What kind of algorithms does the
end entity support. The cryptographic strength of the system
SHOULD be at least as strong as the algorithms and keys used for
the certificate being managed.
* Algorithm profile: The overall strength of the profile will be the
strength of the weakest algorithm it contains.
* Message protection: The overall strength of the CMC message
protection
- MAC-based protection: The entropy of the shared secret
information or password when MAC-based message protection is
used (MSG_MAC_ALG).
- Signature-based protection: The strength of the key pair and
signature algorithm when signature-based protection is used
(MSG_SIG_ALG).
- Protection of centrally generated keys: The strength of the
algorithms used for the key management technique (Section 7.2:
PROT_ENC_ALG or Section 7.1: KM_KA_ALG, KM_KT_ALG, KM_KD_ALG)
and the encryption of the content-encryption key and private
key (Section 7.2: SYM_PENC_ALG, PROT_SYM_ALG or Section 7.1:
KM_KW_ALG, PROT_SYM_ALG).
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The following table shows the algorithms listed in this document
sorted by their bits of security. If an implementation intends to
enroll and manage certificate for keys of a specific security, it
SHALL implement and use algorithms of at least that strength for the
respective PKI management operation. If one row does not provide a
suitable algorithm, the implementer MUST choose one offering more
bits of security.
+=======+==========+================+==================+============+
| Bits | RSA or | Elliptic | Hash Function or | Symmetric |
| of | DH | Curve | XOF with | Encryption |
| Secu- | | | Specified Output | |
| rity | | | Length (d) | |
+=======+==========+================+==================+============+
| 112 | RSA2048, | ECDSA/ECDH | SHA224 | |
| | DH(2048) | (secp224r1) | | |
+-------+----------+----------------+------------------+------------+
| 128 | RSA3072, | ECDSA/ECDH | SHA256, | AES-128 |
| | DH(3072) | (secp256r1), | SHAKE128(d=256) | |
| | | Ed25519/ | | |
| | | X25519 | | |
| | | (Curve25519) | | |
+-------+----------+----------------+------------------+------------+
| 192 | | ECDSA/ECDH | SHA384 | AES-192 |
| | | (secp384r1) | | |
+-------+----------+----------------+------------------+------------+
| 224 | | Ed448/X448 | | |
| | | (Curve448) | | |
+-------+----------+----------------+------------------+------------+
| 256 | | ECDSA/ECDH | SHA512, | AES-256 |
| | | (secp521r1) | SHAKE256(d=512) | |
+-------+----------+----------------+------------------+------------+
Table 1: Cryptographic Algorithms Sorted by their Bits of Security
The following table shows the cryptographic algorithms sorted by
their usage in CMP and with more details.
+========+==========+===============+===============+===============+
|Bits of |Key Types |CMP Protection |Key Management | Key-Wrap and |
|Security|to Be | |Technique | Symmetric |
| |Certified | | | Encryption |
+========+==========+===============+===============+===============+
| | |MSG_SIG_ALG, |PROT_ENC_ALG or| PROT_SYM_ALG, |
| | |MSG_MAC_ALG |KM_KA_ALG, | SYM_PENC_ALG |
| | | |KM_KT_ALG, | or |
| | | |KM_KD_ALG | KM_KW_ALG |
+--------+----------+---------------+---------------+---------------+
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|112 |RSA2048, |RSASSA-PSS |DH(2048), | |
| |secp224r1 |(2048, SHA224 |RSAES-OAEP | |
| | |or SHAKE128 |(2048, SHA224),| |
| | |(d=256)), |RSAEncryption | |
| | |RSAEncryption |(2048, SHA224),| |
| | |(2048, SHA224),|ECDH | |
| | |ECDSA |(secp224r1, | |
| | |(secp224r1, |SHA224), | |
| | |SHA224 or |PBKDF2 (HMAC- | |
| | |SHAKE128 |SHA224) | |
| | |(d=256)), | | |
| | |PBMAC1 (HMAC- | | |
| | |SHA224) | | |
+--------+----------+---------------+---------------+---------------+
|128 |RSA3072, |RSASSA-PSS |DH(3072), | AES-128 |
| |secp256r1,|(3072, SHA256 |RSAES-OAEP | |
| |Curve25519|or SHAKE128 |(3072, SHA256),| |
| | |(d=256)), |RSAEncryption | |
| | |RSAEncryption |(3072, SHA256),| |
| | |(3072, SHA256),|ECDH | |
| | |ECDSA |(secp256r1, | |
| | |(secp256r1, |SHA256), | |
| | |SHA256 or |X25519, | |
| | |SHAKE128 |PBKDF2 (HMAC- | |
| | |(d=256)), |SHA256) | |
| | |Ed25519 | | |
| | |(SHA512), | | |
| | |PBMAC1 (HMAC- | | |
| | |SHA256) | | |
+--------+----------+---------------+---------------+---------------+
|192 |secp384r1 |ECDSA |ECDH | AES-192 |
| | |(secp384r1, |(secp384r1, | |
| | |SHA384), |SHA384), | |
| | |PBMAC1 (HMAC- |PBKDF2 (HMAC- | |
| | |SHA384) |SHA384) | |
+--------+----------+---------------+---------------+---------------+
|224 |Curve448 |Ed448 |X448 | |
| | |(SHAKE256) | | |
+--------+----------+---------------+---------------+---------------+
|256 |secp521r1 |ECDSA |ECDH | AES-256 |
| | |(secp521r1, |(secp521r1, | |
| | |SHA512 or |SHA512), | |
| | |SHAKE256 |PBKDF2 (HMAC- | |
| | |(d=512)), |SHA512) | |
| | |PBMAC1 (HMAC- | | |
| | |SHA512) | | |
+--------+----------+---------------+---------------+---------------+
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Table 2: Cryptographic Algorithms Sorted by their Bits of
Security and Usage by CMP
To avoid consuming too many computational resources it is recommended
to choose a set of algorithms offering roughly the same level of
security. Below are provided several algorithm profiles which are
balanced, assuming the implementer chooses MAC secrets and/or
certificate profiles of at least equivalent strength.
7.1. Algorithm Profile for RFC 4210 PKI Management Message Profiles
The following table updates the definitions of algorithms used within
PKI Management Message Profiles as defined in CMP Appendix D.2
[RFC4210].
The columns in the table are:
Name: An identifier used for message profiles
Use: Description of where and for what the algorithm is used
Mandatory: Algorithms which MUST be supported by conforming
implementations
Optional: Algorithms which are OPTIONAL to support
Deprecated: Algorithms from RFC 4210 [RFC4210] which SHOULD NOT be
used any more
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+============+==============+======+===================+============+
|Name |Use |Manda-| Optional |Deprecated |
| | |tory | | |
+============+==============+======+===================+============+
|MSG_SIG_ALG |protection of |RSA | ECDSA, EdDSA |DSA, |
| |PKI messages | | |combinations|
| |using | | |with MD5 and|
| |signature | | |SHA-1 |
+------------+--------------+------+-------------------+------------+
|MSG_MAC_ALG |protection of |PBMAC1| PasswordBasedMac, |X9.9 |
| |PKI messages | | HMAC, KMAC | |
| |using MACing | | | |
+------------+--------------+------+-------------------+------------+
|SYM_PENC_ALG|symmetric |AES- | |3-DES(3-key-|
| |encryption of |wrap | |EDE, CBC |
| |an end | | |Mode), RC5, |
| |entity's | | |CAST-128 |
| |private key | | | |
| |where | | | |
| |symmetric key | | | |
| |is distributed| | | |
| |out-of-band | | | |
+------------+--------------+------+-------------------+------------+
|PROT_ENC_ALG|asymmetric |DH | ECDH, RSA | |
| |algorithm used| | | |
| |for encryption| | | |
| |of (symmetric | | | |
| |keys for | | | |
| |encryption of)| | | |
| |private keys | | | |
| |transported in| | | |
| |PKIMessages | | | |
+------------+--------------+------+-------------------+------------+
|PROT_SYM_ALG|symmetric |AES- | |3-DES(3-key-|
| |encryption |CBC | |EDE, CBC |
| |algorithm used| | |Mode), RC5, |
| |for encryption| | |CAST-128 |
| |of private key| | | |
| |bits (a key of| | | |
| |this type is | | | |
| |encrypted | | | |
| |using | | | |
| |PROT_ENC_ALG) | | | |
+------------+--------------+------+-------------------+------------+
Table 3: Algorithms Used Within RFC 4210 Appendix D.2
Mandatory Algorithm Identifiers and Specifications:
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RSA: sha256WithRSAEncryption with 2048 bit, see Section 3.1
PasswordBasedMac: id-PasswordBasedMac, see Section 6.1 (with id-
sha256 as the owf parameter, see Section 2.1 and id-hmacWithSHA256 as
the mac parameter, see Section 6.2.1)
PBMAC1: id-PBMAC1, see Section 6.1.2 (with id-PBKDF2 as the key
derivation function, see Section 4.4.1 and id-hmacWithSHA256 as
message authentication scheme, see Section 6.2.1). It is RECOMMENDED
to prefer the usage of PBMAC1 instead of PasswordBasedMac.
DH: id-alg-ESDH, see Section 4.1.1
AES-wrap: id-aes128-wrap, see Section 4.3.1
AES-CBC: id-aes128-CBC, see Section 5.1
7.2. Algorithm Profile for Lightweight CMP Profile
The following table contains definitions of algorithms which MAY be
supported by implementations of the Lightweight CMP Profile
[I-D.ietf-lamps-lightweight-cmp-profile].
As the set of algorithms to be used for implementations of the
Lightweight CMP Profile heavily depends on the PKI management
operations implemented, the certificates used for messages
protection, and the certificates to be managed, this document will
not specify a specific set that is mandatory to support for
conforming implementations.
The columns in the table are:
Name: An identifier used for message profiles
Use: Description of where and for what the algorithm is used
Examples: Lists the algorithms as described in this document. The
list of algorithms depends on the set of PKI management operations to
be implemented.
Note: It is RECOMMENDED to prefer the usage of PBMAC1 instead of
PasswordBasedMac.
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+==============+================================+==================+
| Name | Use | Examples |
+==============+================================+==================+
| MSG_SIG_ALG | protection of PKI messages | RSA, ECDSA, |
| | using signature and for | EdDSA |
| | SignedData, e.g., a private | |
| | key transported in PKIMessages | |
+--------------+--------------------------------+------------------+
| MSG_MAC_ALG | protection of PKI messages | PasswordBasedMac |
| | using MACing | (see Section 9), |
| | | PBMAC1, HMAC, |
| | | KMAC |
+--------------+--------------------------------+------------------+
| KM_KA_ALG | asymmetric key agreement | DH, ECDH |
| | algorithm used for agreement | |
| | of a symmetric key for use | |
| | with KM_KW_ALG | |
+--------------+--------------------------------+------------------+
| KM_KT_ALG | asymmetric key encryption | RSA |
| | algorithm used for transport | |
| | of a symmetric key for | |
| | PROT_SYM_ALG | |
+--------------+--------------------------------+------------------+
| KM_KD_ALG | symmetric key derivation | PBKDF2 |
| | algorithm used for derivation | |
| | of a symmetric key for use | |
| | with KM_KW_ALG | |
+--------------+--------------------------------+------------------+
| KM_KW_ALG | algorithm to wrap a symmetric | AES-wrap |
| | key for PROT_SYM_ALG | |
+--------------+--------------------------------+------------------+
| PROT_SYM_ALG | symmetric content encryption | AES-CBC |
| | algorithm used for encryption | |
| | of EnvelopedData, e.g., a | |
| | private key transported in | |
| | PKIMessages | |
+--------------+--------------------------------+------------------+
Table 4: Algorithms Used Within Lightweight CMP Profile
8. IANA Considerations
This document does not request changes to the IANA registry.
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9. Security Considerations
This document lists many cryptographic algorithms usable with CMP to
offer implementer a more up-to-date choice. Finally, the algorithms
to be supported also heavily depend on the certificates and PKI
management operations utilized in the target environment. The
algorithm with the lowest security strength and the entropy of shared
secret information define the security of the overall solution, see
Section 7.
When using MAC-based message protection the use of PBMAC1 is
preferable to that of PasswordBasedMac. First, PBMAC1 is a well-
known scrutinized algorithm, which is not true for PasswordBasedMac.
Second, the PasswordBasedMac algorithm as specified in RFC 4211
Section 4.4 [RFC4211] is essentially PBKDF1 (as defined in RFC 8018
Section 5.1 [RFC8018]) with an HMAC step at the end. Here we update
to use the PBKDF2-HMAC construct defined as PBMAC1 in [RFC8018].
PBKDF2 is superior to PBKDF1 in an improved internal construct for
iterated hashing, and in removing PBKDF1's limitation of only being
able to derive keys up to the size of the underlying hash function.
Additionally, PBKDF1 is not recommended for new applications as
stated in Section 5.1 of RFC 8018 [RFC8018] and no longer an approved
algorithm by most standards bodies, and therefore presents
difficulties to implementer who are submitting their CMP
implementations for certification, hence moving to a PBKDF2-based
mechanism. This change is in alignment with [RFC9045] which updates
[RFC4211] to allow the use of PBMAC1 in CRMF.
AES-GMAC MUST NOT be used as the pseudo random function in PBKDF2;
the use of AES-GMAC more than once with the same key and the same
nonce will break the security.
In Section 7 of this document there is also an update to the
Appendix D.2 of RFC 4210 [RFC4210] and a set of algorithms that MAY
be supported when implementing the Lightweight CMP Profile
[I-D.ietf-lamps-lightweight-cmp-profile].
It is recognized that there may be older CMP implementations in use
that conform to the algorithm use profile from Appendix D.2 of
RFC 4210 [RFC4210]. For example, the use of AES is now mandatory for
PROT_SYM_ALG but in RFC 4210 [RFC4210] 3-DES was mandatory.
Therefore, it is expected that many CMP systems may already support
the recommended algorithms in this specification. In such systems
the weakened algorithms should be disabled from further use. If
critical systems cannot be immediately updated to conform to the
recommended algorithm use profile, it is recommended a plan to
migrate the infrastructure to conforming profiles be adopted as soon
as possible.
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Symmetric key-based MAC algorithms as described in Section 6.2 MAY be
used as MSG_MAC_ALG. The implementer MUST choose a suitable PRF and
ensure that the key has sufficient entropy to match the overall
security level of the algorithm profile. These considerations are
outside the scope of the profile.
10. Acknowledgements
Thanks to Russ Housley for supporting this draft with submitting
[RFC9044] and [RFC9045].
May thanks also to all reviewers like Serge Mister, Mark Ferreira,
Yuefei Lu, Tomas Gustavsson, Lijun Liao, David von Oheimb and Steffen
Fries for their input and feedback to this document. Apologies to
all not mentioned reviewers and supporters.
11. Normative References
[I-D.ietf-lamps-cmp-updates]
Brockhaus, H., Oheimb, D. V., and J. Gray, "Certificate
Management Protocol (CMP) Updates", Work in Progress,
Internet-Draft, draft-ietf-lamps-cmp-updates-20, 31 May
2022, <https://datatracker.ietf.org/doc/html/draft-ietf-
lamps-cmp-updates-20>.
[I-D.ietf-lamps-lightweight-cmp-profile]
Brockhaus, H., Oheimb, D. V., and S. Fries, "Lightweight
Certificate Management Protocol (CMP) Profile", Work in
Progress, Internet-Draft, draft-ietf-lamps-lightweight-
cmp-profile-12, 13 May 2022,
<https://datatracker.ietf.org/doc/html/draft-ietf-lamps-
lightweight-cmp-profile-12>.
[NIST.FIPS.180-4]
Dang, Quynh H., "Secure Hash Standard", NIST NIST FIPS
180-4, DOI 10.6028/NIST.FIPS.180-4, July 2015,
<https://nvlpubs.nist.gov/nistpubs/FIPS/
NIST.FIPS.180-4.pdf>.
[NIST.FIPS.186-4]
National Institute of Standards and Technology (NIST),
"Digital Signature Standard (DSS)", NIST NIST FIPS 186-4,
DOI 10.6028/NIST.FIPS.186-4, July 2013,
<https://nvlpubs.nist.gov/nistpubs/FIPS/
NIST.FIPS.186-4.pdf>.
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[NIST.FIPS.186-5]
National Institute of Standards and Technology (NIST),
"FIPS Pub 186-5 (Draft): Digital Signature Standard
(DSS)", October 2019,
<https://nvlpubs.nist.gov/nistpubs/FIPS/
NIST.FIPS.186-5-draft.pdf>.
[NIST.FIPS.197]
National Institute of Standards and Technology (NIST),
"Advanced encryption standard (AES)", NIST NIST FIPS 197,
DOI 10.6028/NIST.FIPS.197, November 2001,
<https://nvlpubs.nist.gov/nistpubs/FIPS/
NIST.FIPS.197.pdf>.
[NIST.FIPS.198-1]
National Institute of Standards and Technology (NIST),
"The Keyed-Hash Message Authentication Code (HMAC)",
NIST NIST FIPS 198-1, DOI 10.6028/NIST.FIPS.198-1, July
2008, <https://nvlpubs.nist.gov/nistpubs/FIPS/
NIST.FIPS.198-1.pdf>.
[NIST.FIPS.202]
Dworkin, Morris J., "SHA-3 Standard: Permutation-Based
Hash and Extendable-Output Functions", NIST NIST FIPS 202,
DOI 10.6028/NIST.FIPS.202, July 2015,
<https://nvlpubs.nist.gov/nistpubs/FIPS/
NIST.FIPS.202.pdf>.
[NIST.SP.800-185]
Kelsey, John., Change, Shu-jen., and Ray. Perlner, "SHA-3
derived functions: cSHAKE, KMAC, TupleHash and
ParallelHash", NIST NIST SP 800-185,
DOI 10.6028/NIST.SP.800-185, December 2016,
<https://nvlpubs.nist.gov/nistpubs/SpecialPublications/
NIST.SP.800-185.pdf>.
[NIST.SP.800-38d]
Dworkin, M J., "Recommendation for block cipher modes of
operation :GaloisCounter Mode (GCM) and GMAC", NIST NIST
SP 800-38d, DOI 10.6028/NIST.SP.800-38d, 2007,
<https://nvlpubs.nist.gov/nistpubs/Legacy/SP/
nistspecialpublication800-38d.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>.
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[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>.
[RFC2631] Rescorla, E., "Diffie-Hellman Key Agreement Method",
RFC 2631, DOI 10.17487/RFC2631, June 1999,
<https://www.rfc-editor.org/info/rfc2631>.
[RFC3370] Housley, R., "Cryptographic Message Syntax (CMS)
Algorithms", RFC 3370, DOI 10.17487/RFC3370, August 2002,
<https://www.rfc-editor.org/info/rfc3370>.
[RFC3394] Schaad, J. and R. Housley, "Advanced Encryption Standard
(AES) Key Wrap Algorithm", RFC 3394, DOI 10.17487/RFC3394,
September 2002, <https://www.rfc-editor.org/info/rfc3394>.
[RFC3560] Housley, R., "Use of the RSAES-OAEP Key Transport
Algorithm in Cryptographic Message Syntax (CMS)",
RFC 3560, DOI 10.17487/RFC3560, July 2003,
<https://www.rfc-editor.org/info/rfc3560>.
[RFC3565] Schaad, J., "Use of the Advanced Encryption Standard (AES)
Encryption Algorithm in Cryptographic Message Syntax
(CMS)", RFC 3565, DOI 10.17487/RFC3565, July 2003,
<https://www.rfc-editor.org/info/rfc3565>.
[RFC4056] Schaad, J., "Use of the RSASSA-PSS Signature Algorithm in
Cryptographic Message Syntax (CMS)", RFC 4056,
DOI 10.17487/RFC4056, June 2005,
<https://www.rfc-editor.org/info/rfc4056>.
[RFC4210] Adams, C., Farrell, S., Kause, T., and T. Mononen,
"Internet X.509 Public Key Infrastructure Certificate
Management Protocol (CMP)", RFC 4210,
DOI 10.17487/RFC4210, September 2005,
<https://www.rfc-editor.org/info/rfc4210>.
[RFC4211] Schaad, J., "Internet X.509 Public Key Infrastructure
Certificate Request Message Format (CRMF)", RFC 4211,
DOI 10.17487/RFC4211, September 2005,
<https://www.rfc-editor.org/info/rfc4211>.
[RFC4231] Nystrom, M., "Identifiers and Test Vectors for HMAC-SHA-
224, HMAC-SHA-256, HMAC-SHA-384, and HMAC-SHA-512",
RFC 4231, DOI 10.17487/RFC4231, December 2005,
<https://www.rfc-editor.org/info/rfc4231>.
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[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>.
[RFC5753] Turner, S. and D. Brown, "Use of Elliptic Curve
Cryptography (ECC) Algorithms in Cryptographic Message
Syntax (CMS)", RFC 5753, DOI 10.17487/RFC5753, January
2010, <https://www.rfc-editor.org/info/rfc5753>.
[RFC5754] Turner, S., "Using SHA2 Algorithms with Cryptographic
Message Syntax", RFC 5754, DOI 10.17487/RFC5754, January
2010, <https://www.rfc-editor.org/info/rfc5754>.
[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>.
[RFC8018] Moriarty, K., Ed., Kaliski, B., and A. Rusch, "PKCS #5:
Password-Based Cryptography Specification Version 2.1",
RFC 8018, DOI 10.17487/RFC8018, January 2017,
<https://www.rfc-editor.org/info/rfc8018>.
[RFC8032] Josefsson, S. and I. Liusvaara, "Edwards-Curve Digital
Signature Algorithm (EdDSA)", RFC 8032,
DOI 10.17487/RFC8032, January 2017,
<https://www.rfc-editor.org/info/rfc8032>.
[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>.
[RFC8418] Housley, R., "Use of the Elliptic Curve Diffie-Hellman Key
Agreement Algorithm with X25519 and X448 in the
Cryptographic Message Syntax (CMS)", RFC 8418,
DOI 10.17487/RFC8418, August 2018,
<https://www.rfc-editor.org/info/rfc8418>.
[RFC8419] Housley, R., "Use of Edwards-Curve Digital Signature
Algorithm (EdDSA) Signatures in the Cryptographic Message
Syntax (CMS)", RFC 8419, DOI 10.17487/RFC8419, August
2018, <https://www.rfc-editor.org/info/rfc8419>.
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[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>.
[RFC9044] Housley, R., "Using the AES-GMAC Algorithm with the
Cryptographic Message Syntax (CMS)", RFC 9044,
DOI 10.17487/RFC9044, June 2021,
<https://www.rfc-editor.org/info/rfc9044>.
[RFC9045] Housley, R., "Algorithm Requirements Update to the
Internet X.509 Public Key Infrastructure Certificate
Request Message Format (CRMF)", RFC 9045,
DOI 10.17487/RFC9045, June 2021,
<https://www.rfc-editor.org/info/rfc9045>.
12. Informative References
[ECRYPT.CSA.D5.4]
University of Bristol, "Algorithms, Key Size and Protocols
Report (2018)", March 2015,
<https://www.ecrypt.eu.org/csa/documents/
D5.4-FinalAlgKeySizeProt.pdf>.
[NIST.SP.800-57pt1r5]
Barker, Elaine., "Recommendation for key management:part 1
- general", NIST NIST SP 800-57pt1r5,
DOI 10.6028/NIST.SP.800-57pt1r5, May 2020,
<https://nvlpubs.nist.gov/nistpubs/SpecialPublications/
NIST.SP.800-57pt1r5.pdf>.
[RFC8551] Schaad, J., Ramsdell, B., and S. Turner, "Secure/
Multipurpose Internet Mail Extensions (S/MIME) Version 4.0
Message Specification", RFC 8551, DOI 10.17487/RFC8551,
April 2019, <https://www.rfc-editor.org/info/rfc8551>.
[RFC8692] Kampanakis, P. and Q. Dang, "Internet X.509 Public Key
Infrastructure: Additional Algorithm Identifiers for
RSASSA-PSS and ECDSA Using SHAKEs", RFC 8692,
DOI 10.17487/RFC8692, December 2019,
<https://www.rfc-editor.org/info/rfc8692>.
Appendix A. History of Changes
Note: This appendix will be deleted in the final version of the
document.
From version 14 -> 15:
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* Providing changes addressing comment from Martin Duke and
Zaheduzzaman Sarker regarding the introduction
From version 13 -> 14:
* Providing changes addressing comments from GEN AD review
From version 12 -> 13:
* Providing changes addressing comments from OPSDIR and GENART last
call reviews
From version 11 -> 12:
* Capitalized all headlines
From version 10 -> 11:
* Changes on the tables in Section 7 after direct exchange with
Quynh
From version 09 -> 10:
* Removed the pre-RFC5378 work disclaimer after the RFC 4210 authors
granted BCP78 rights to the IETF Trust
* Implemented the changes proposed by Quynh, (see thread "Quynh
Action: draft-ietf-lamps-cmp-algorithms-08.txt") and removed
markers for ToDos regarding this review of SHAKE and KMAC usage as
well as on the tables in Section 7
From version 08 -> 09:
* Updated IPR disclaimer
From version 07 -> 08:
* Fixing issues from WG and AD review
* Adding Note to Section 2.2, 3.3, and 6.2.3 regarding usage of
SHAKE and KMAC and added ToDo regarding checking respective notes
* Added two tables showing algorithms sorted by their strength to
Section 7 and added ToDo regarding checking these tables
* Updates the algorithm use profile in Section 7.1
* Updated and added security consideration on SHAKE,
PasswordBasedMac, KMAC, and symmetric key-based MAC functions and
added ToDo regarding checking the security consideration on SHAKE
From version 06 -> 07:
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* Fixing minor formatting nits
From version 05 -> 06:
* Added text to Section 2 and Section 3.3 to clearly specify the
hash algorithm to use for certConf messages for certificates
signed with EdDSA (see thread "[CMP Updates] Hash algorithm to us
for calculating certHash")
* Updated new RFC numbers for I-D.ietf-lamps-cms-aes-gmac-alg and I-
D.ietf-lamps-crmf-update-algs
From version 04 -> 05:
* Minor changes and corrections in wording
From version 03 -> 04:
* Added John Gray to the list of authors due to his extensive
support and valuable feedback
* Added some clarification of the use AES-GMAC to Section 6.2.1
* Extended the guidance on how to select a set of algorithms in
Section 7 and deleted former Section 7.1
* Deleted the algorithms mandatory to support in Section 7.2 as
discussed at IETF 110
* Extended the Security considerations in Section 9
* Minor changes in wording
From version 02 -> 03:
* Moved former Appendix A to new Section 7 as suggested by Rich and
Russ (see thread "I-D Action: draft-ietf-lamps-cmp-algorithms-
02.txt")
* Added a column to Table 1 in Section 7.2 to reflect the changes to
RFC 4210
* Updated Table 2 in Section 7.3
* Added a paragraph to Section 9 to discuss backward compatibility
with RFC 4210
* Minor changes in wording
From version 01 -> 02:
* Added Hans Aschauer, Mike Ounsworth, and Serge Mister as co-author
* Changed to XML V3
* Added SHAKE digest algorithm to Section 2 as discussed at IETF 109
* Deleted DSA from Section 3 as discussed at IETF 109
* Added RSASSA-PSS with SHAKE to Section 3
* Added SECP curves the section on ECDSA with SHA2, ECDSA with
SHAKE, and EdDSA to Section 3 as discussed at IETF 109
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* Deleted static-static D-H and ECDH from Section 4.1 based on the
discussion on the mailing list (see thread "[CMP Algorithms]
Section 4.1.1 and 4.1.2 drop static-static (EC)DH key agreement
algorithms for use in CMP")
* Added ECDH OIDs and SECP curves, as well as ECDH with curve25519
and curve448 to Section 4.1 as discussed at IETF 109
* Deleted RSA-OAEP from Section 4.2 first as discussed at IETF 109,
but re-added it after discussion on the mailing list (see thread
"Mail regarding draft-ietf-lamps-cmp-algorithms")
* Added a paragraph to Section 4.3.1 to explain that the algorithms
and key length for content encryption and key wrapping must be
aligned as discussed on the mailing list (see thread "[CMP
Algorithms] Use Key-Wrap with or without padding in Section 4.3
and Section 5")
* Deleted AES-CCM and AES-GMC from and added AES-CBC to Section 5 as
discussed at IETF 109
* Added Section 6.1.2 to offer PBMAC1 as discusses on the mailing
list (see thread "Mail regarding draft-ietf-lamps-crmf-update-
algs-02") and restructured text in Section 6 to be easier to
differentiate between password- and shared-key-based MAC
* Deleted Diffie-Hellmann based MAC from Section 6 as is only
relevant when using enrolling Diffie-Hellmann certificates
* Added AES-GMAC and SHAKE-based KMAC to Section 6 as discussed at
IETF 109
* Extended Section 9 to mention Russ supporting with two additional
I-Ds and name further supporters of the draft
* Added a first draft of a generic algorithm selection guideline to
Appendix A
* Added a first proposal for mandatory algorithms for the
Lightweight CMP Profile to Appendix A
* Minor changes in wording
From version 00 -> 01:
* Changed sections Symmetric Key-Encryption Algorithms and Content
Encryption Algorithms based on the discussion on the mailing list
(see thread "[CMP Algorithms] Use Key-Wrap with or without padding
in Section 4.3 and Section 5")
* Added Appendix A with updated algorithms profile for RDC4210
Appendix D.2 and first proposal for the Lightweight CMP Profile
* Minor changes in wording
Authors' Addresses
Hendrik Brockhaus (editor)
Siemens AG
Email: hendrik.brockhaus@siemens.com
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Hans Aschauer
Siemens AG
Email: hans.aschauer@siemens.com
Mike Ounsworth
Entrust
Email: mike.ounsworth@entrust.com
John Gray
Entrust
Email: john.gray@entrust.com
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