Re: [dane] email canonicalization for SMIMEA owner names

[Nico Williams <[e-mail]>]

On Fri, Dec 12, 2014 at 01:36:56AM +0000, Viktor Dukhovni wrote:
> On Thu, Dec 11, 2014 at 05:22:03PM -0800, Ian Fette (????????) wrote:
> > Sorry, just reading the SMIMEA stuff for the first time, so apologies for
> > the basic question, but do I really have to publish a record for each
> > address? How would I say "this is a trusted intermediate CA for *@gmail.com
> > "?
> 
> That would look like so:
> 
>     ;; insert CNAMEs for any desired indirection when
>     ;; the same set of SMIMEA RRs handles multiple domains
>     ;;
>     *._smimecert.gmail.com IN SMIMEA 2 0 1 <blob>
> 
> Keep in mind that this only supports signature verification, not
> encryption, one can't encrypt to an intermediate CA, one needs the
> leaf public key for that.  So enabling encryption on first contact
> requires publishing per-user keys by some means.

There's always IBE, or just plain encrypting to the MTA's encryption
cert and then let it decrypt and re-encrypt to the local-part's
encryption key.

> Otherwise all one gets is authenticated key exchange, possibly
> followed later by encryption once leaf keys have been exchanged in
> both directions.

That's not so bad.  It's interactive, but so what.

Nico
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