Re: [dane] email canonicalization for SMIMEA owner names

Viktor Dukhovni <ietf-dane@dukhovni.org> Sat, 13 December 2014 18:33 UTC

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Date: Sat, 13 Dec 2014 18:33:37 +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 Sat, Dec 13, 2014 at 06:17:24PM -0000, John Levine wrote:

> * verify an incoming signature without reference to a CA
> * encrypt mail to people who haven't already sent you a key
> 
> Of the two, the second seems much more important.  If it's only the
> first, I don't think it's worth the effort.

[ I understand and in part agree with your point, but I think
  even the first alone is not as vacuous as it might seem. ]

Well I don't see to many organizations outsourcing user enrollment
to a CA, or wanting to operate an RA, so the CA-trust thing is not
so much the issue as the problem of getting CA signatures for the
user certificates, having to handle revocation via a CA, ...

What DANE can do is make it possible to just use your enterprise
CA.  For example, the Microsoft CA is very difficult to use for a
Windows shop, with DANE this can be extend to issuing certificates
that others can validate.

And I am not sure that first contact end-to-end encryption in which
only the final recipient gets to read the mail will be terribly
popular in a world of spam and email malware.  In many ways,
signature-only with key exchange on reply has security advantages
that may make it a popular mode of deployment.

-- 
	Viktor.