Re: [Ietf-dkim] DKIM-Signature: r=y and MLM

"Murray S. Kucherawy" <> Sat, 18 August 2018 22:02 UTC

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From: "Murray S. Kucherawy" <>
Date: Sat, 18 Aug 2018 15:02:35 -0700
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To: Dilyan Palauzov <>
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Subject: Re: [Ietf-dkim] DKIM-Signature: r=y and MLM
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On Fri, Aug 10, 2018 at 8:38 PM, Dilyan Palauzov <>

> I suggest here in to suggest in a more formal manner, that MLMs modifying
> a message are supposed to remove the r=y part of just invalidated
> DKIM-Signature and this logic is also applied for ARC, if relevant (I don't
> know ARC).  Fixing only ARC will not help, as there is software that
> follows DKIM, but has no idea about ARC.
> Is such a recommendation a good idea?
> How to make the recomentation?  Amendment to RFC6377, amendment to RFC
> 6651, something else, that is very short to compose?

I think advising anyone to alter a signature on a message irrespective of
the signature's validity will be hard to sell.  It would be simpler to just
remove the signature entirely if there's a good reason not to want it there

This unfortunately seems a rather small thing for which to spin up an
update to either RFC6377 or RFC6651.  Are there any other things that have
evolved since those documents were published that might make revisions
worth doing?