Re: [dmarc-ietf] Nitpicky questions about DMARC record syntax

"John Levine" <johnl@taugh.com> Wed, 16 January 2019 19:18 UTC

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From: "John Levine" <johnl@taugh.com>
To: dmarc@ietf.org
Cc: dcrocker@gmail.com
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Subject: Re: [dmarc-ietf] Nitpicky questions about DMARC record syntax
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In article <7c8aa4a8-7d75-db07-7e97-82d9b0ffb29a@gmail.com> you write:
>If more flexibility is viewed by the community as desirable, then the 
>community should enhance the specification to allow it.  This improves 
>robustness while retaining a firm, clear and precise standard.

Do keep in mind that most of the DMARC records I've looked at follow
the spec.  They may not have the expected policy, but the syntax is
fine.  If a small minority get it wrong, I think it's better to
educate and fix them than to try to guess when someone misreads the
spec in a way that leads them to screw up the syntax of the record,
but not to screw up anything else.

Remember, that if your software rewrites an invalid record into a
correct one, you are trying to read the mind of the person who wrote
the misformed record.  I can guess what v=dmarc1 was supposed to say
but I have no clue what pct:1 is supposed to mean.  Let's not start.

R's,
John