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CURves, Deprecating and a Little more Encryption

Document Charter CURves, Deprecating and a Little more Encryption WG (curdle)
Title CURves, Deprecating and a Little more Encryption
Last updated 2019-03-27
State Approved
WG State Concluded
IESG Responsible AD Benjamin Kaduk
Charter edit AD Benjamin Kaduk
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CURDLE - CURves, Deprecating and a Little more Encryption

The CURDLE working group is chartered to add a small set of cryptographic mechanisms to some IETF protocols, and to make implementation requirements including deprecation of old algorithms where there is IETF consensus to do so. The focus with regards to adding mechanisms is for those mechanisms that enjoy broad support from implementers.

The set of cryptographic mechanisms that can be introduced are limited to key agreement (ECDH) and digital signatures (EdDSA) with Curve25519 and Curve448 as defined by CFRG [1] [2], and the AEAD mode ciphers consisting of ChaCha20 and Poly1305 also defined by CFRG [3]. Other variants of mechanisms, such as the ChaCha20-Poly1305 construct deployed for SSH, may also be considered as well as AES-CCM[4] and AES-GCM [5] where those are not already defined and where there is implementer interest. Related specifications such as private and public key formats are also within scope.

The protocols the WG intends to work on are Secure Shell (SSH), DNSSEC, PKIX, CMS, XML Digital Signatures and potentially XML Encryption, Kerberos and JSON.

Where initial drafts for this work have been produced those will be immediately considered for adoption as working group documents. These include, for SSH, Curve25519/Curve448 digital signatures [6] and key exchange [7]; for DNSSEC, Ed25519 [8] and Curve448 [9]; for PKIX, Curve25519/448 NamedCurve [10] and EdDSA signatures [11]; for JSON curves and signatures [12].

The CURDLE working group will be handling changes to protocols and registries some of which include what are now considered outdated algorithm options, and may propose deprecation of such algorithms. Such deprecation needs to be done with care, ensuring that interoperability and the needs of existing implementers and deployments are properly considered. Where deprecation is practical, the working group is encouraged to deprecate.

Where there is an IETF working group or area group with expertise in a relevant topic the CURDLE working group will defer to the consensus of the more specific working group as to where work will be done. For example, the TLS, OpenPGP and IPSECME WGs are actively considering some of these topics.

The CURDLE working group will liaise with W3C to ensure that XML digital signature and XML encryption work does not conflict with W3C.

The CURDLE working group is expected to be a short-lived working group that may not need to ever meet face-to-face. Once the work on the initially adopted set of drafts has completed the working group will close or re-charter.

The CURDLE working group is not chartered to consider allocating new codepoints for any algorithms or modes other than those mentioned above. Should someone wish to propose such work, a re-charter will be required. At this time, there is no expectation that such a re-charter will be requested.

[3] RFC 7539
[4] RFC 3610
[5] RFC5288