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

John Levine <johnl@taugh.com> Mon, 01 February 2021 23:11 UTC

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From: John Levine <johnl@taugh.com>
To: dmarc@ietf.org
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Subject: Re: [dmarc-ietf] Ticket #1 - SPF alignment
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In article <babf1538-5172-f101-d5e4-c4fa33dea495@tana.it> you write:
>On Mon 01/Feb/2021 01:10:01 +0100 Scott Kitterman wrote:
>> I think that we're well past learning anything new in this thread.
>> 
>> SPF is what it is (RFC 7208).  DMARC doesn't need to re-invent the protocol
>> (and shouldn't).  For any properly implemented SPF verifier, DMARC should be
>> able to consume the Mail From result.
>
>Perhaps Courier-MTA is not so properly implemented, but when mail from is empty 
>it just omits the corresponding Received-SPF: header field.

That's a peculiarity of Courier.  My MTA adds an SPF clause in the A-R header
whether or not there's a null bounce address.

>OTOH, properly implemented SPF verifiers could skip producing a Mail From 
>result if the helo identity was verified successfully.

No, they could not.  That's not what the SPF spec says.

>It makes sense to add a section that modifies RFC 7208.  See below.

Please, can we stop the Mission Gallop?

R's,
John