Re: DMARC and

=JeffH <> Thu, 18 August 2016 18:28 UTC

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From: =JeffH <>
Subject: Re: DMARC and
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Date: Thu, 18 Aug 2016 11:28:07 -0700
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I'd scrawled..
 > The W3C mailing list manager (MLM) is apparently configured to do
 > rfc5322.from field re-writing which seems to ameliorate the DMARC-MLM
 > issues (in my experience, at least), and it would be helpful if the IETF
 > would take similar measures.

just fyi, I double-checked and I was incorrect regarding what the W3C 
MLM is doing -- it is actually "doing as little as possible", wrt 
message modifications, when sending email to list subscribers. Thus 
there is greater likelihood of DKIM and SPF signatures remaining valid.

the mailing lists I was apparently thinking of, that are doing From: 
field rewriting, are ones.

part of the reason for my re-surfacing the DMARC issue wrt 
lists is that apparently my work MTA is bouncing msgs for 
DMARC-protected domains (with p=quarantine or p=reject) that do not 
validate, and the MLM then disables my subscription to the 
mailing list in question (sigh. at least it notifies me).

although I have not sent email to the mozilla lists from my 
dmarc-protected work address (AFAIK), I do note that I have not (AFAIK) 
received any disable/unsubscribe notifications from, 
and there have been folks posting to those lists from e.g. 
(p=reject,pct=100), so perhaps the From-field rewriting they are doing 
is "working" (for some definition of "working").