Re: DMARC: perspectives from a listadmin of large open-source lists

Dave Crocker <dcrocker@bbiw.net> Mon, 14 April 2014 14:25 UTC

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Date: Mon, 14 Apr 2014 07:23:49 -0700
From: Dave Crocker <dcrocker@bbiw.net>
Organization: Brandenburg InternetWorking
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To: John C Klensin <john-ietf@jck.com>, Doug Barton <dougb@dougbarton.us>, ietf@ietf.org
Subject: Re: DMARC: perspectives from a listadmin of large open-source lists
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On 4/14/2014 2:14 AM, John C Klensin wrote:
> There is a strong rule in RFC 5321 and its predecessor
> forbidding anything but the final delivery system from rewriting
> a local-part and it is there precisely because one doesn't know
> what sorts of conventions and indicates were begin used there.


Just to avoid possible confusion about the implications of the above:

      Mediators, like mailing lists, take final delivery and post a new 
message.  In formal terms, it's legitimate for them to create a 
different rfc5322.From field, including one that looks like some sort of 
'rewrite' of the one used by the original author.

d/

-- 
Dave Crocker
Brandenburg InternetWorking
bbiw.net