Re: [dmarc-ietf] DMARC'ed reports, was Forensic report loops are a problem

Alessandro Vesely <> Tue, 02 February 2021 17:39 UTC

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To: Dave Crocker <>, John R Levine <>
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From: Alessandro Vesely <>
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Date: Tue, 2 Feb 2021 18:39:43 +0100
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Subject: Re: [dmarc-ietf] DMARC'ed reports, was Forensic report loops are a problem
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On Tue 02/Feb/2021 18:24:32 +0100 Dave Crocker wrote:
> On 2/2/2021 9:19 AM, Alessandro Vesely wrote:
>> I changed it again, for failure reports, like so:
>> 3.3.  Transport
>>    Email streams carrying DMARC failure reports SHOULD conform to the
>>    DMARC mechanism, thereby resulting in an aligned "pass".  This
> "conform to" seems odd wording; it's not immediately obvious what it means here.
> Perhaps:
>   SHOULD provide DMARC-based authentication, to produce their own aligned "pass"
>> requirement is a MUST in case the sending host has a DMARC record
> 'sending host' is ambiguous in this context.

Is this better:

3.3.  Transport

    Email streams carrying DMARC failure reports SHOULD provide DMARC-
    based authentication, so as to produce "dmarc=pass".  This
    requirement is a MUST in case the report is sent through a host
    having a DMARC record with a ruf= tag.  Indeed, special care must be
    taken of authentication in that case, as failure to authenticate
    failure reports may result in mail loops.

    Reporters SHOULD rate limit the number of failure reports sent to any
    recipient to avoid overloading recipient systems.  Again, in case the
    reports being sent are in turn at risk of being reported for DMARC
    authentication failure, reporters MUST make sure that possible mail
    loop are stopped.