On 8 Apr 2014, at 05:21, John R Levine <johnl(_at_)taugh(_dot_)com> wrote:
Mailing list apps can't "implement DMARC" other than by getting rid of every
feature that makes lists more functional than simple forwarders. Given that
we haven't done so for any of the previous FUSSPs that didn't contemplate
mailing lists, because those features are useful to our users, it seems
unlikely we'll do so now.
Well, Mailman 2.1.16 has the FROM_IS_LIST feature that "Fixes" the problem by
putting the list address in the From: field. That seems to work, except that
you lose information (the sender's address) if the list wants to operate a
policy of "Reply goes to list". You can then assure that DKIM signatures are
valid and set up SPF, etc. This also has the effect of letting you operate
through the various cloud email platforms that try to validate sender addresses.
But I agree it's broken.
Cheers,
Sabahattin