Re: [openpgp] SHA3 algorithm ids.

"Robert J. Hansen" <rjh@sixdemonbag.org> Wed, 19 August 2015 14:19 UTC

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From: "Robert J. Hansen" <rjh@sixdemonbag.org>
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Date: Wed, 19 Aug 2015 10:19:35 -0400
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Subject: Re: [openpgp] SHA3 algorithm ids.
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> And that's pretty much what the -224 hashes are, forgettable (and 
> -384 only slightly less so).  There's an obvious need for -256, and 
> then you need -512 for people who need hashes that go to 11, but 
> what's the point of -224 and -384 in OpenPGP?

IIRC, early drafts of DSA2 required a 224-bit hash for DSA-2048 and
didn't allow for the possibility of a truncated 256-bit hash.  Later
revisions corrected this oversight.  That's where it got into the spec:
because at the time it got into the spec, SHA-224 was required for
conformance.