[lamps] Re: [EXTERNAL] Re: WG Last Call for draft-ietf-lamps-kyber-certificates-07

[Mike Ounsworth <[e-mail]>]

I agree that the concept of “Mandatory-to-implement” within IETF X.509 behaves a bit differently than MTI in other WGs.

 

As Russ says, there is no global “Every X.509 or CMS implementation MUST support X”.

 

But I think what Dan is getting at has a kernel of truth to it also: a given LAMPS specification can contain both mandatory and optional components. For example, draft-ietf-lamps-cms-kyber says “A compliant implementation MUST support HKDF with SHA-256” as the KEMRecipientInfo.KDF – so *IF* you implement ML-KEM within CMS, then it is mandatory to implement HKDF-SHA256, *BUT* you are allowed to implement CMS without implementing ML-KEM. MTI within this draft, but not globally MTI for CMS. It’s weird. My brain hurts now.

 

---

Mike Ounsworth

 

From: Russ Housley <[e-mail]> 
Sent: Sunday, January 12, 2025 11:09 AM
To: Dan Bernstein <[e-mail]>
Cc: [e-mail]; [e-mail]
Subject: [EXTERNAL] [lamps] Re: WG Last Call for draft-ietf-lamps-kyber-certificates-07

 

Dan: >> This is not a mandator-to-implement algorithm. If one chooses to >> implement this specification, then that implementer will obviously >> need to implement ML-KEM. > > That makes the algorithm mandatory to implement. 



Dan:
 
>> This is not a mandator-to-implement algorithm.  If one chooses to
>> implement this specification, then that implementer will obviously
>> need to implement ML-KEM.
> 
> That makes the algorithm mandatory to implement.
 
We disagree on a vey fundamental level. The PKIX WG and the LAMPS WG have been very clear that there are no mandatory-to-implement algorithms in the PKI specifications.  Rather, othr WGs that specify protocols that make use of PKI can make algorithms selections.  For example, S/MIME and TLS are two protocols that use PKI.  S/MIME 4.0 (RFCs 8550 and 8551) includes statements about mandatory-to-implement algorithms.  The TLS 1.3 (RFC 8446) includes statements about mandatory-to-implement algorithms. 
 
Russ
_______________________________________________
Spasm mailing list -- [e-mail] <mailto:[e-mail]> 
To unsubscribe send an email to [e-mail] <mailto:[e-mail]>