[lamps] Review of draft-ietf-lamps-cms-kyber-03

[Jonathan Hammell <[e-mail]>]

I reviewed draft-ietf-lamps-cms-kyber-03 following Monday's LAMPS
session at IETF 119.  Daniel had asked in the session if the
KEMRecipientInfo Processing Summary in Section 1.4 copied from
draft-ietf-lamps-cms-kemri should be removed.  I think it would
benefit simplicity if it was removed.

The introductory sentence ("Processing ML-KEM with KEMRecipientInfo
follows the same steps as Section 2 of [I-D.ietf-lamps-cms-kemri]")
and the two requirement statements on implementation ("To support the
ML-KEM algorithm, the CMS originator MUST implement Encapsulate()" and
"To support the ML-KEM algorithm, the CMS recipient MUST implement
Decapsulate()") can be included as a second paragraph at the beginning
of Section 2.  The note regarding the KDF ("Note that the KDF used to
process the KEMRecipientInfo structure MAY be different from the KDF
used in the ML-KEM algorithm") can be included in 2.2.2.

As Daniel pointed out, this section was included to align with
draft-ietf-lamps-rfc5990bis-05.  A similar change to remove Section
1.3 of rfc5590bis and merge the requirements into 1.2 could be made.
Otherwise, I don't feel it is necessary to align exactly if the
authors choose not to do so.  rfc5990bis is already different in that
it is defining the RSA-KEM algorithm in addition to specifying how it
is used in CMS.

I also think that Section 1.2 introducing KEMs should be removed from
this ML-KEM draft.

The title for Section 2.2.1 would be more informative as "Use of the
KMAC-based Key Derivation Function (KDF)".

Section 2.2.2 uses both the term "key wrapping" and "key-encryption".
Stick with one (likely the former).

There is a small typo in the ASN.1 OID definition of aes in Section 3:
an underscore following "csor(3)".

The Security Considerations in Section 4 should also say that the
Security Considerations of [I-D.ietf-lamps-cms-kemri] applies.

My thanks to the authors for preparing this document.

Best regards,
Jonathan

Canadian Centre for Cyber Security
https://cyber.gc.ca