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

Theodore Ts'o <tytso@mit.edu> Tue, 15 April 2014 23:17 UTC

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Date: Tue, 15 Apr 2014 19:17:20 -0400
From: Theodore Ts'o <tytso@mit.edu>
To: Brian E Carpenter <brian.e.carpenter@gmail.com>
Subject: Re: DMARC: perspectives from a listadmin of large open-source lists
Message-ID: <20140415231720.GQ4456@thunk.org>
References: <534B524F.4050206@dcrocker.net> <alpine.BSF.2.00.1404132327560.26258@joyce.lan> <E0B7196CB2603B80BBEC21AF@JcK-HP8200.jck.com> <alpine.BSF.2.00.1404132346420.26386@joyce.lan> <1EBDF5239EEE5202D3837D25@JcK-HP8200.jck.com> <534B9760.90301@dougbarton.us> <6C80882F19CCEDFE15E987CA@JcK-HP8200.jck.com> <534BEF75.5060804@bbiw.net> <534DB093.5020507@qti.qualcomm.com> <534DBA0F.2050507@gmail.com>
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On Wed, Apr 16, 2014 at 11:00:31AM +1200, Brian E Carpenter wrote:
> 
> > (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.)
> 
> Isn't that exactly what p=reject implies? If so, the logical behaviour
> for all list software would be to check the DMARC record for the
> originating domain of each message, and bounce it if p=reject.

The question is which is more or less unfriendly? 

1)  Forbidding yahoo.com users from participating on mailing lists

2)  Rewriting the from field of yahoo.com users.

I could easily see the mailing list software making this be
configurable, so it's up to each mailing list admin.  :-)

	      	      	    	 	      	      - Ted

P.S.  #1 could also be combined with a nice message inviting the
yahoo.com user to find another e-mail provider.