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[openpgp] Why or why not SHA{2,3}-512 (was: SHA3 algorithm ids)

Werner Koch <wk@gnupg.org> Tue, 11 August 2015 15:46 UTC

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From: Werner Koch <wk@gnupg.org>
To: Phillip Hallam-Baker <phill@hallambaker.com>
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Date: Tue, 11 Aug 2015 17:41:12 +0200
In-Reply-To: <CAMm+LwifPNxyj1LLA-k+8K=mmEztS42E2kcEfGFObPc0R2xvMQ@mail.gmail.com> (Phillip Hallam-Baker's message of "Tue, 11 Aug 2015 10:16:43 -0400")
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Subject: [openpgp] Why or why not SHA{2,3}-512 (was: SHA3 algorithm ids)
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On Tue, 11 Aug 2015 16:16, phill@hallambaker.com said:

> every option. If you are going to sign a 1Gb file then you are going to
> need multiple trips through the digest function. Now there is of course a

This is not an option for OpenPGP!  OpenPGP has been carefully designed
to allow its use in a pipe ("online" in current parlance).  Any signing
function which requires multiple passes over the signed data is useless.
(I heard of encrypted(+signed) backups in the TiB range.)


Shalom-Salam,

   Werner


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