[Mailman-Developers] Adding DMARC support for Mailman 3

[Patrick Ben Koetter]

Greetings,

I am writing on behalf of a group of companies and single persons, who would
like to see a limited feature set of the DMARC¹ standard supported by Mailman
3.

Since I know we're all eager to get MM3 out as soon as possible and any
additional new feature request stands against that I've contacted Barry offlist
and asked if he'd agree that the companies involved pay us, sys4², to implement
the feature. He did and we also agreed to dedicate a significant part of the
payment to mailman's FSF donation account.

Before we take out to write code, I would like to ask mailman-developers how it
should be done to fit best into Mailman's architecture. Here are the DMARC
features that should go into Mailman 3:

- don't allow email that comes from a domain with a DMRAC record of p=reject
- take ownership of the email and send it with a From: using the
  domain of the mailing list. (There's a patch for this for Mailman 2.1, which
  might might be helpful for Mailman 3.)
- find the authentication-results header and rewrite it as an
  Original-Authentication-header:
  http://tools.ietf.org/html/draft-kucherawy-original-authres-00.html

Speaking of an RFC written by Murray Kucherawy. I've contacted Murray in
advance and asked him to assist in case we had any questions regarding his
RFC(s). He subscribed and ready to help.

I hope I was able to bring all parties required together to make a Mailman
DMARC implementation come true and I am curious to hear what you have to say.

p at rick


¹) DMARC <http://www.dmarc.org/> adds policies and more to DKIM, which gives
digitally signed identity to sender domains and has become a cornerstone to
reputation based mail management. Having DMARC support in Mailman 3 is - in my
eyes - a reason for postmasters (not end-users) to upgrade their MM 2.x
installation as soon as possible.

²) In case you ask yourself, who "sys4" is: We've accompanied Mailman 3
development since Pycon in Chicago (in 2008 ?). Florian Fuchs, whom I don't
have to introduce, works with us as well Ralf Hildebrandt and I. We, Ralf and
I, are on the python.org postmaster team. Also with sys4 are Antoine Nguyen
and Christian Roesser - both are exerienced Python programmers and both have
spent significant time developing email applications.

-- 
[*] sys4 AG
 
http://sys4.de, +49 (89) 30 90 46 64
Franziskanerstraße 15, 81669 München
 
Sitz der Gesellschaft: München, Amtsgericht München: HRB 199263
Vorstand: Patrick Ben Koetter, Axel von der Ohe, Marc Schiffbauer
Aufsichtsratsvorsitzender: Florian Kirstein