Re: [openpgp] [RFC4880bis PATCH] WIP: bind wire format representations to specific pubkey algorithms

Daniel Kahn Gillmor <dkg@fifthhorseman.net> Sat, 05 June 2021 17:55 UTC

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From: Daniel Kahn Gillmor <dkg@fifthhorseman.net>
To: Daniel Huigens <d.huigens@protonmail.com>
Cc: IETF OpenPGP WG <openpgp@ietf.org>
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Date: Sat, 05 Jun 2021 13:30:24 -0400
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Subject: Re: [openpgp] [RFC4880bis PATCH] WIP: bind wire format representations to specific pubkey algorithms
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Hi Daniel--

thanks for your thinking and reading about this!

On Fri 2021-06-04 19:27:16 +0000, Daniel Huigens wrote:
> For what it's worth, I fully agree that the current situation with
> Curve25519 is non-ideal and confusing, and that a simple byte string
> would be better. However, we'll likely be stuck with it forever, and I'm
> not sure if specifying a different wire format for Curve448 makes things
> any simpler.

I think this is a fair read -- whether i agree with it or not -- and i
hope that we can have the discussion about what to do about curve448
*independently* from this proposed revision/clarification.

I put my preference about curve448 in the commit message/comment section
just to be transparent about my own thinking, but i don't think that the
propopsal commits the WG to handling curve448 one way or the other.

(there is a possible exception with the line the "This format is NOT
RECOMMENDED for use when specifying future algorithms with OpenPGP, but
it is necessary for handling pre-existing data." -- but if we parse that
line as meaning "once the new RFC is out the door" it still gives us
wiggle room to specify Curve448 in the way that Daniel is recommending
here)

So for this thread, i'd appreciate it if we can analyze the attempted
clarifications offered -- i might have got them wrong, and i'd really
appreciate more reviews to ensure that we've got them right.

We can decide about curve448 later!

Regards,

        --dkg