Re: [dane] email canonicalization for SMIMEA owner names

Viktor Dukhovni <ietf-dane@dukhovni.org> Thu, 11 December 2014 23:55 UTC

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Date: Thu, 11 Dec 2014 23:55:19 +0000
From: Viktor Dukhovni <ietf-dane@dukhovni.org>
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Subject: Re: [dane] email canonicalization for SMIMEA owner names
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On Thu, Dec 11, 2014 at 04:15:01PM -0600, Nico Williams wrote:

> If I want to
> publish SMIMEA RRs for all possible capitalizations of "foo"
> @bar.example, well I can, and if I don't want to then I don't have to.

The problem is that (without my encoding) a client can't tell
whether the "foo@example.com" key it found really is the
"FOO@example.com" it wanted to reach, or whether that is some other
mailbox.  Yes, any mailbox provider that assigned mailboxes that
way would be insane, but not "criminally insane"... :-)

So my "@local:" prefix avoids collisions if there are in fact sites
where mailboxes are case-sensitive.

I am pleased with John Levine's characterization of my proposal:

    * It's terrible.
    * We may as well use it.

Like passwords for authentication (or democracy as a form of
governance), it stinks, but the other options stink more.

-- 
	Viktor.