Re: [CFRG] compact representation and HPKE
Eric Rescorla <ekr@rtfm.com> Fri, 12 February 2021 22:14 UTC
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From: Eric Rescorla <ekr@rtfm.com>
Date: Fri, 12 Feb 2021 14:13:32 -0800
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To: Dan Harkins <dharkins@lounge.org>
Cc: CFRG <cfrg@irtf.org>
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Subject: Re: [CFRG] compact representation and HPKE
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On Fri, Feb 12, 2021 at 2:00 PM Dan Harkins <dharkins@lounge.org> wrote: > > On 2/12/21 1:10 PM, Eric Rescorla wrote: > > As I understand it, the competing values here are: > > (1) A technically superior approach (x-coordinate only) > (2) Consistency with existing uses of these curves (e.g., in TLS 1.3, > which uses x-coordinate-only form for CFRG curves but uncompressed form for > NIST curves). > > Assuming I understand this correctly, I think I value consistency more, > especially in light of the fact that we are encouraging people to move to > CFRG curves anyway, which are already in the technically superior form. > > > I see. So we go with the technically inferior approach, in order to > "encourage people > to move to the CFRG curves." > I don't think that this reflects a fair reading of what I wrote above, and in any case is not what I meant. Rather what I am trying to say is that we should weigh the costs of having an inferior interface to the NIST curves less heavily because we want people to move to CFRG curves anyway, at which point this will be an non-issue. We should go with the "technically superior approach", especially when > that results > in a cleaner and more consistent API for HPKE. > The problem is that this comes at a less clean and consistent API for the underlying cryptographic primitives which then have to be different depending on which protocol they are embedded in. -Ekr
- [CFRG] compact representation and HPKE Dan Harkins
- Re: [CFRG] compact representation and HPKE John Mattsson
- Re: [CFRG] compact representation and HPKE Richard Barnes
- Re: [CFRG] compact representation and HPKE Mike Hamburg
- Re: [CFRG] compact representation and HPKE Dan Harkins
- Re: [CFRG] compact representation and HPKE Dan Harkins
- Re: [CFRG] compact representation and HPKE John Mattsson
- Re: [CFRG] compact representation and HPKE Michael Scott
- Re: [CFRG] compact representation and HPKE Michael Scott
- Re: [CFRG] compact representation and HPKE Dan Harkins
- Re: [CFRG] compact representation and HPKE Benjamin Beurdouche
- Re: [CFRG] compact representation and HPKE Dan Harkins
- Re: [CFRG] compact representation and HPKE Loup Vaillant-David
- Re: [CFRG] compact representation and HPKE Eric Rescorla
- Re: [CFRG] compact representation and HPKE Christopher Wood
- Re: [CFRG] compact representation and HPKE Paul Hoffman
- Re: [CFRG] compact representation and HPKE Dan Harkins
- Re: [CFRG] compact representation and HPKE Stephen Farrell
- Re: [CFRG] compact representation and HPKE Eric Rescorla
- Re: [CFRG] compact representation and HPKE Stephen Farrell
- Re: [CFRG] compact representation and HPKE Andrey Jivsov
- Re: [CFRG] compact representation and HPKE Mike Hamburg
- Re: [CFRG] compact representation and HPKE Mike Hamburg
- Re: [CFRG] compact representation and HPKE Loup Vaillant-David
- Re: [CFRG] compact representation and HPKE Salz, Rich
- Re: [CFRG] compact representation and HPKE Mike Hamburg
- Re: [CFRG] compact representation and HPKE Stephen Farrell
- Re: [CFRG] compact representation and HPKE Peter Gutmann
- Re: [CFRG] compact representation and HPKE John Mattsson
- Re: [CFRG] compact representation and HPKE Benjamin Lipp
- Re: [CFRG] compact representation and HPKE John Mattsson
- Re: [CFRG] compact representation and HPKE Mike Hamburg
- Re: [CFRG] compact representation and HPKE Salz, Rich
- Re: [CFRG] compact representation and HPKE Dan Harkins
- Re: [CFRG] compact representation and HPKE Karthik Bhargavan
- Re: [CFRG] compact representation and HPKE Richard Barnes
- Re: [CFRG] compact representation and HPKE Eric Rescorla
- Re: [CFRG] compact representation and HPKE Benjamin Beurdouche
- Re: [CFRG] compact representation and HPKE Dan Harkins
- Re: [CFRG] compact representation and HPKE Billy Brumley
- Re: [CFRG] compact representation and HPKE Stanislav V. Smyshlyaev
- Re: [CFRG] compact representation and HPKE Dan Harkins
- Re: [CFRG] compact representation and HPKE Stanislav V. Smyshlyaev
- Re: [CFRG] compact representation and HPKE John Mattsson
- Re: [CFRG] compact representation and HPKE denis bider