Re: [openpgp] Non-SHA-1 fingerprints in signatures [was: Proposal for a separable ring signature scheme...]

Peter Pentchev <roam@ringlet.net> Fri, 14 March 2014 14:44 UTC

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Date: Fri, 14 Mar 2014 16:44:15 +0200
From: Peter Pentchev <roam@ringlet.net>
To: Vincent Yu <v@v-yu.com>
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Cc: openpgp@ietf.org, Daniel Kahn Gillmor <dkg@fifthhorseman.net>
Subject: Re: [openpgp] Non-SHA-1 fingerprints in signatures [was: Proposal for a separable ring signature scheme...]
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On Fri, Mar 14, 2014 at 10:36:23AM -0400, Vincent Yu wrote:
> On 03/14/2014 10:24 AM, Peter Pentchev wrote:
> >On Thu, Mar 13, 2014 at 10:39:31PM -0400, Vincent Yu wrote:
> >>Thanks for the info. I will likely follow your suggestion and modify
> >>my proposal to use V4 fingerprints rather than key IDs.
> >
> >Hm, how exactly would this deal with the existence of multiple signing
> >subkeys, all associated with the same master public key?  Your current
> >proposal explicitly allows for that, using the key IDs; I guess there
> >might be a need to include *both* the fingerprint of the master key
> >*and* some kind of identification of the subkey actually used for
> >signing.
> 
> Isn't there a V4 fingerprint defined for every key, including for
> each subkey? I think it would be okay just to include the
> fingerprints of all possible signing keys, regardless of whether
> they are primary keys or subkeys.
> 
> If I've misunderstood something, please let me know.

Argh, sorry, stupid of me; of course you're right.  I was a bit misled
by the fact that GnuPG, by default, only outputs the fingerprint of the
primary key when --fingerprint is specified on the command line; I kind
of missed the part where --fingerprint may be given more than once and
it will output the fingerprints of all the subkeys.

G'luck,
Peter

-- 
Peter Pentchev	roam@ringlet.net roam@FreeBSD.org p.penchev@storpool.com
PGP key:	http://people.FreeBSD.org/~roam/roam.key.asc
Key fingerprint 2EE7 A7A5 17FC 124C F115  C354 651E EFB0 2527 DF13
If the meanings of 'true' and 'false' were switched, then this sentence wouldn't be false.