Re: [openpgp] On Signed-Only Mails

Brian Sniffen <bsniffen@akamai.com> Tue, 29 November 2016 19:12 UTC

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From: Brian Sniffen <bsniffen@akamai.com>
To: Vincent Breitmoser <look@my.amazin.horse>, openpgp@ietf.org,
In-Reply-To: <20161129091837.GA25812@littlepip.fritz.box>
References: <20161129091837.GA25812@littlepip.fritz.box>
Date: Tue, 29 Nov 2016 14:13:18 -0500
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Subject: Re: [openpgp] On Signed-Only Mails
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Vincent Breitmoser <look@my.amazin.horse> writes:
> In short, my conclusion so far is that signed-only mails are very rarely
> useful, they are holding OpenPGP back as a solution for encrypted
> e-mail, and in the interest of usability we should not roll them out in
> email crypto solutions on equal terms with encryption.
>
> In some more detail:
> https://k9mail.github.io/2016/11/24/OpenPGP-Considerations-Part-I.html

Perhaps you don't see the use cases, but I see many every day: signed
e-mail messages for e-mail based manipulation of databases (e.g., bug
trackers, auto-builders, deployment systems).  Clearsigning is
particularly useful because it lets me CC others (they see the command
language, have an opportunity to learn it, question my action---the
social setting of e-mail works very well for interaction with this sort
of command language).

I suppose I could just clearsign a region of a text e-mail, but (a) that
means I need an even more complex UI on mobile devices, and (b) I don't
trust my mail chain not to screw up the formatting---which is part of
why we have PGP/MIME in the first place.  The next-best alternative is
a web interface, but that removes the ability to manage it through
mail---with all the threading and conversation conventions that come
with it.


I'm also curious about the UI: do you expect to only offer
(encrypted+signed) and (plaintext)?  If there are separate toggles for
encryption and signature anyway, what's the UI benefit?

-Brian