Re: [dmarc-ietf] DMARC aggregate reports XML Schema inconsistencies

Alessandro Vesely <vesely@tana.it> Tue, 06 August 2019 17:36 UTC

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From: Alessandro Vesely <vesely@tana.it>
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Subject: Re: [dmarc-ietf] DMARC aggregate reports XML Schema inconsistencies
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On Wed 31/Jul/2019 11:47:29 +0200 Freddie Leeman wrote:
> [...]
> 
> DMARC reporting capabilities are a valuable aspect of the DMARC mechanism. It
> can help domain owners in setting up and hardening their DKIM/SPF/DMARC policy.
> But unless these reports follow strict guidelines they just pile up to a lot of
> inconsistent data open to interpretation and guesswork. Domain owners should be
> able to understand the data without the need for a spiritual voodoo DMARC guru
> (trademark pending) to make sense of it all.


I had tried and programmed carefully, but never formally checked what I was
sending.  Too bad.  Now that I did, I see my reports miss the <pct> and <fo>[*]
elements, and some other nuisance.

However, the most striking difference is that, after some tinkering, to be able
to formally validate a report, it has to be rewritten like so:

    <?xml version="1.0" encoding="UTF-8"?>
    <dmarc:feedback xmlns:xs="http://www.w3.org/2001/XMLSchema-instance"
        xmlns:dmarc="http://dmarc.org/dmarc-xml/0.1"
        xs:schemaLocation="http://dmarc.org/dmarc-xml/0.1 rua.xsd">
        <report_metadata>
            <org_name>example.com</org_name>
            <email>postmaster@example.com</email>
            [...]

Is that correct?  Is that how reports should be written?  I ask because
checking some aggregate report I received, I found no mention of namespaces and
schema locations.  XSLT works well even without those.  Validation doesn't.

What do you reckon?


Best
Ale

-- 
[*] <fo> is present in Appendix C of the spec, but not in
https://dmarc.org/dmarc-xml/0.1/rua.xsd