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

Damian Lukowski <rfc@arcsin.de> Fri, 03 April 2020 20:41 UTC

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From: Damian Lukowski <rfc@arcsin.de>
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Subject: Re: [dmarc-ietf] Spirit of RFC8601 section 5 for invalid A-R headers
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> The system should remove the quotes when comparing, and should also do
> any decoding to get the admds into the same format.

My question's intent was not particularly about the quotes and UTF-8, I
just chose it, because the syntactically invalid version looks more
legit than the syntactically valid one. Assume some plain-ASCII
examples. A mail system with own authservid of domain.tld receives mail
with:

> Authentication-Results: domain.tld; spf=pass smtp.mailfrom=x@y.z

Needs to be removed? Clearly yes.

> Authentication-Results: otherdomain.tld; spf=pass smtp.mailfrom=x@y.z

Needs to be removed? Clearly no.

> Authentication-Results: {garbage}

Needs to be removed? I say no.

> Authentication-Results: domain.tld, spf=pass smtp.mailfrom=x@y.z

Needs to be removed? I say no.

> Authentication-Results: domain.tld; {garbage}

Needs to be removed? I say no.

> Authentication-Results: "domain.tld"; {garbage}

Needs to be removed? I say no.

> Authentication-Results: "domain.tld"; spf=pass smtp.mailfrom=x@y.z

Needs to be removed? Yes.