Re: [dmarc-ietf] Ticket #42 - Expand DMARC reporting URI functionality

Alessandro Vesely <vesely@tana.it> Thu, 31 December 2020 15:02 UTC

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To: John R Levine <johnl@taugh.com>, dmarc@ietf.org
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From: Alessandro Vesely <vesely@tana.it>
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Subject: Re: [dmarc-ietf] Ticket #42 - Expand DMARC reporting URI functionality
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On Wed 30/Dec/2020 22:23:20 +0100 John R Levine wrote:
> There was some discussion about the detail that if there are multiple addresses 
> in the rua= tag you send the report to all of them.  People were quite clear 
> that is a feature.  I proposed as a hack a ruap= tag for rua preferred, if the 
> reporting system can send reports to all of the URIs in the ruap tag it does 
> so, otherwise it uses rua as it does now.  That lets you put the https URIs in 
> the ruap tag which existing code will ignore.
> 
> Didn't get a lot of comments pro or con on that one.


I still like better sticking to a unique tag (rua=) and applying OR-slashes.  With a comma, it is backward compatible:

v=DMARC1; p=none; rua=mailto:local@example.com, mailto:report@service.example, /https://service.example/report/;

(The first scheme without a leading slash introduces a new series of alternatives.)

The main reason to stick to the same tag is to allow overriding.  For example, if the above record were:

$ORIGIN=_dmarc.example.com
IN TXT "v=DMARC1; p=none; rua=mailto:local@example.com, mailto:report@service.example"

Then service.example can override rua=:

$ORIGIN=example.com._report._dmarc.service.example
IN TXT "v=DMARC1; rua=mailto:report@service.example, /https://service.example/report/;


Best
Ale
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