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

Michael Thomas <mike@mtcc.com> Sat, 30 January 2021 22:44 UTC

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From: Michael Thomas <mike@mtcc.com>
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Subject: Re: [dmarc-ietf] Ticket #1 - SPF alignment
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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.

Mike