Re: What I've been wondering about the DMARC problem

"John Levine" <johnl@taugh.com> Fri, 18 April 2014 01:35 UTC

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Date: 18 Apr 2014 01:34:33 -0000
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From: "John Levine" <johnl@taugh.com>
To: ietf@ietf.org
Subject: Re: What I've been wondering about the DMARC problem
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>> The mailman fix is worse than the disease. I think the .INVALID fix is
>> much better, because Reply-all will still work.
>
>>From the latest DMARC draft, section 8:
>
>"If the RFC5322.From domain does not exist in the DNS, Mail Receivers
>SHOULD direct the receiving SMTP server to reject the message."

As far as I can tell, that bit of poor advice hasn't been implemented.


>So if a receiver that is implementing DMARC is faithful to the draft,
>that won't work very well (nobody has gotten a TLD allocation for
>.invalid, I hope?)

See RFC 2606.

R's,
John

PS: I did a few experiments, and putting two addresses on the From:
line works remarkably well to avoid inappropriate policy failures,
e.g.

 From: Marissa <marissam@yahoo.com>om>, foo-list@ietf.org
 Subject: whatever
 ...