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Re: [Cose] Key management for MACs (was Re: Review of draft-schaad-cose-msg-01)

Ilari Liusvaara <ilari.liusvaara@elisanet.fi> Fri, 10 July 2015 09:36 UTC

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Date: Fri, 10 Jul 2015 12:36:37 +0300
From: Ilari Liusvaara <ilari.liusvaara@elisanet.fi>
To: Jim Schaad <ietf@augustcellars.com>
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Cc: 'Brian Campbell' <bcampbell@pingidentity.com>, cose@ietf.org
Subject: Re: [Cose] Key management for MACs (was Re: Review of draft-schaad-cose-msg-01)
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On Thu, Jul 09, 2015 at 06:12:49PM -0700, Jim Schaad wrote:
>  
> Looking at the new signature formats coming out of CFRG, I am not sure
> what the lengths of the signatures are,

AFAICT,

64 or 112-114 bytes (packable to 112 with some bit shuffling). One
proposal allows half-length hash, giving 48 or 84 bytes.

Public keys are 32 or 57 bytes.

(All can be defined on intermediate size curves too, for
intermediate signature/pubkey size at intermediate security).



-Ilari

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