On Tue, 20 Jan 2015 16:14:32 CST, 
Franck Martin <[email protected]> wrote:

> [...]
> Your confusion on HELO is may be related to the fact that the
> HELO string is only used when the MAIL-FROM: is empty?
>
> There is some text here:
> http://trac.tools.ietf.org/html/rfc7208#section-10.1.3
> 
> The HELO string is not evaluated all the time, it is more like
> a fall back.

It's already been pointed out that
   http://trac.tools.ietf.org/html/rfc7208#section-2.3
RECOMMENDs checking the HELO string first; hence our confusion.
It'a not difficult to imagine a HELO string that passes SPF but
doesn't align with the RFC5322.From with a MAIL FROM domain that
passes SPF *and* aligns, while the DKIM-Signature validates but
doesn't align.  An implementation of DMARC that follows the SPF
recommendation will, as I understand it, produce [SPF:fail,
DKIM:fail], despite the existence of an SPF-valid MAIL FROM
domain that aligns with the RFC5322.From domain.  It seems
to be the consensus that this would be wrong, and that existing
DMARC implementations don't behave that way.  That's fine by me,
but it needs to be said out loud that DMARC implementations
MUST NOT (SHOULD NOT?) follow rfc7208#section-2.3's
recommendation.

> Also I have trouble to understand why you may be affected by
> your OD? What is the relation between your domain and your OD?
> I suspect this is concordia.ca?

Yes, it's Concordia.ca.  Some details:  Concordia.ca is Concordia
University, while encs.concordia.ca is just the Faculty of
Engineering and Computer Science at Concordia, so it's
appropriate that concordia.ca is the OD.  They've delegated 
encs.concordia.ca to us, and we (ENCS staff) manage it ourselves,
with minimal interaction.

> If you look at the public suffix list, google has put a
> separation at blogspot.com level, so that each hosting domain,
> can be organizationally separated.
> 
> https://publicsuffix.org/list/effective_tld_names.dat

Are you saying that any owner of a registered domain can
arrange to the suffix list on request, thereby allowing
next-level subdomains to be elevated to ODs?  If that's
right, I'd certainly be keen on suggesting to our
concordia.ca colleagues that they do us that favour.

> I would suggest you publish a DMARC record in monitoring mode
> (p=none) so that you get reports (and no impact) and better
> understand your email infrastructure and what needs to be done.

We'll certainly publish a DMARC record with p=none.

Thanks,

MJA

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