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

Pete Resnick <> Tue, 15 April 2014 22:20 UTC

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Date: Tue, 15 Apr 2014 17:20:03 -0500
From: Pete Resnick <>
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To: Dave Crocker <>
Subject: Re: DMARC: perspectives from a listadmin of large open-source lists
References: <20140414024956.26078.qmail@joyce.lan> <> <alpine.BSF.2.00.1404132327560.26258@joyce.lan> <> <alpine.BSF.2.00.1404132346420.26386@joyce.lan> <> <> <> <>
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On 4/14/14 9:23 AM, Dave Crocker wrote:

> 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.

It's legitimate for a mailing list to rewrite the author, but it would 
be wrong. :-)

More seriously: If the mailing list wishes to express that I am the 
author of *this message*, then I belong in the "From:" field. That 
differs semantically from forwarding a message authored by me; then the 
list is saying that the list is the author, and it is simply quoting me, 
but that the list is the entity that should be considered to have 
written the message. For most mailing lists, that seems like the wrong 
semantics to try to convey.

There should be a mechanism for an author to send a message to a mailing 
list, granting the mailing list permission to redistribute that message, 
and have that permission conveyed to the mailing list recipient such 
that when the mailing list recipient receives the message, they can 
assure themselves that the originating domain is OK with that 
redistribution. Sounds like some protocol which could be written.

(If the originating domain is expressly *not* OK with the 
redistribution, the mailing list should bounce the message back to the 
author saying as much.)


Pete Resnick<>
Qualcomm Technologies, Inc. - +1 (858)651-4478