Re: [dmarc-ietf] Ticket #1 - SPF alignment

Scott Kitterman <sklist@kitterman.com> Sat, 30 January 2021 23:06 UTC

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From: Scott Kitterman <sklist@kitterman.com>
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Date: Sat, 30 Jan 2021 18:06:17 -0500
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Subject: Re: [dmarc-ietf] Ticket #1 - SPF alignment
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On Saturday, January 30, 2021 5:44:47 PM EST Michael Thomas wrote:
> On 1/30/21 2:09 PM, John R Levine wrote:
> > On Sat, 30 Jan 2021, Jim Fenton wrote:
> >>> Part of the problem here is that DMARC generally sits on top of an
> >>> SPF library which doesn't tell you how it got its result.  My DMARC
> >>> code just calls the SPF library and uses the result.  I suppose I
> >>> could put in a hack to say don't use the SPF result if the MAIL FROM
> >>> is null, but I don't think that's what 7489 says.
> >> 
> >> Are changes to 7489 off the table here? I didn’t know.
> > 
> > They are certainly possible, but I would want a good reason.  At this
> > point, SPF using HELO seems harmless so I don't see a reason to
> > disallow it.
> 
>  From a security standpoint, I wonder why you would want to allow
> something you know can be gamed. But that is probably more a question
> for SPF itself.

From a DMARC perspective, I don't think it can be in any useful way.  Agree 
that digging into it further is more about SPF itself, presumably OT here.

Scott K