Re: [Secdispatch] [EXTERNAL]Re: Can Composite sigs move back to LAMPS?

[Stephen Farrell <[e-mail]>]

Replying to a few mails at once, but ISTM this is starting
to get repetitive.

On 17/01/2020 18:15, John Gray wrote:
> Hi Stephen,
> 
> The reason why we are putting together this composite standard is 
> because we believe we are in this position today.   If NIST  decides 
> no Round 3 is needed, then we will know the PQ winners by June of 
> this year.   Even if there is a Round 3, and no final set of PQ 
> algorithms is declared until 2021 or 2022, we want to have a hybrid 
> standard ready for us use.  We will need to implement, test, and 
> interop and all these things take time and have to be done after 
> there is a standard.  If we wait too long, it will be a free for 
> all.

Right now there are too many algorithms to believe that
we'd have other than a free-for-all as those pushing one
or another try get their thing adopted. I'd also note
that NIST has a history or defining new parameterisations
after algorithm selection, so wouldn't be surprised if
that happened here too. I'd prefer we wait and see what
results from the NIST thing rather adopt work now in
the IETF. If people want to do work ahead of NIST then
that's of course fine, but adopting such work in the IETF
is asking us all to do work on this now, and I think that's
both risky and wasteful.

> 
> There are already a small handful of stable PQ algorithms available 
> to use today.   See RFC 8391 (XMSS) and RFC 8554 (LMS), so using a 
> hybrid RSA or EC with XMSS or LMS in a composite form is already 
> viable.  The choices are definitely few at this moment, but there
> are viable use-cases.

Stateful signature schemes such as those are not suited
for use in X.509 IMO, as was already raised on the list.
(And someone earlier claimed they wouldn't work for their
use-cases, so I'm confused as to whether the proponents
here do or don't want to include stateful signature
schemes.)

On 17/01/2020 17:54, Mike Ounsworth wrote:
> Cool. In the meantime, we plan to keep working on the outstanding 
> TODO decision points in the draft as more vendors approach us for 
> interop testing. :-)

I've no objection to people working on stuff. I am opposed
to the IETF prematurely adopting work in this space though.

On 17/01/2020 18:08, Carrick Bartle wrote:
> From what I've gathered from the mailing list discussion on this 
> topic (in particular, the lead time necessary for hardware), it 
> strikes me that there is sufficient reason for this work to advance.

My experience in the IETF is that ill-defined and less well
understood work takes longest. I think this matches that at
the moment. I'd suggest the proponents might be better
spending time on developing their work by implementing it
in open-source generic PKI libraries and applications so
that they can produce some non arm-waving evidence as to
what this does or doesn't break. (IMO, it'll turn out to
break a lot and change many lines of code, but who knows,
I may be wrong.)

On 17/01/2020 18:32, Valery Smyslov wrote:
> Given the usual IETF performance, a year is a term just to launch a 
> real work and realize where to go. So, I think we should start doing 
> it now to have plenty of time and not to be in a hurry later.

See above as to how to speed things up more effectively.
Additionally, the idea that waiting a year or so means
someone would have to "be in a hurry" seems questionable
to me.

Cheers,
S.