Re: [dmarc-ietf] Spirit of RFC8601 section 5 for invalid A-R headers

John Levine <johnl@taugh.com> Fri, 03 April 2020 20:09 UTC

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From: "John Levine" <johnl@taugh.com>
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Subject: Re: [dmarc-ietf] Spirit of RFC8601 section 5 for invalid A-R headers
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In article <CABa8R6sbHLfkzHD4gaPBxQbgNy57J1eLXt2sPyAfaTYAY3tG-Q@mail.gmail.com> you write:
>In practice, I don't know how common it is for clients to consume this
>header.

They have to if they're adding ARC seals on the way out.  Other than
that I don't have much idea either.  On my system my mailing list software
looks at it them to decide how much DMARC hackery to do but again I don't
know how common that is.

Since the point of the text is that you can only trust your own A-R
headers, presumably the code that adds them and that consumes them are
at least partly under the same management so I'd think they could agree
on their quoting practices.

R's,
John