Re: [dane] email canonicalization for SMIMEA owner names

Nico Williams <nico@cryptonector.com> Thu, 11 December 2014 22:15 UTC

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Date: Thu, 11 Dec 2014 16:15:01 -0600
From: Nico Williams <nico@cryptonector.com>
To: "Rose, Scott W." <scott.rose@nist.gov>
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Subject: Re: [dane] email canonicalization for SMIMEA owner names
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On Thu, Dec 11, 2014 at 02:51:27PM -0500, Rose, Scott W. wrote:
> Realized the other action item I was assigned to from the interim meeting was email canonicalization for SMIMEA.  I believe it stems from Viktor Dukhovni's email to the endymail list:
> http://www.ietf.org/mail-archive/web/endymail/current/msg00134.html

Er, the case-(in)sensitivity of DNS seems irrelvant here (re: Viktor's
point (e) in that post).  After all, we'd be hashing the local-part.

All that matters is that senders, resenders, ... preserve the form given
them by recipients.

So maybe we need no canonicalization step at all.

If I say I'm foo@bar.example, and you type Foo@bar.example into your
MUA to send me e-mail, you might not reach me.

That seems fair.  And allows for aliases of any kind.  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.

Nico
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