Re: New email address

On Tue, Nov 24, 2015 at 4:00 PM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:

> Alvaro Herrera <alvherre(at)2ndquadrant(dot)com> writes:
> > Magnus Hagander wrote:
> >> That's a direct effect of the dmarc policy change. Yahoo no longer
> supports
> >> their customers using mailing lists. They changed their policies for
> such
> >> emails to hard reject, which makes Gmail (and presumably others) stick
> them
> >> in spam.. It would happen to all the emails except the ones where you
> are
> >> on direct cc.
>
> > FWIW we've been rejecting posts coming from @yahoo.com addresses for a
> > long time now, since DMARC was first introduced. We didn't get around
> > to blocking other domains owned by Yahoo such as ymail.com or national
> > yahoo subdomains, but I assume (without checking) that those will cause
> > trouble too and we will have to block them out in order not to fill our
> > queues with useless bounces.
>
> FWIW, my neighborhood's mailing list just recently implemented some
> changes that were supposed to allow the list to work again for Yahoo
> and other DMARC-affected users, after quite some time without service.
> I don't know how successful they were at that, nor how difficult the
> changes were ... but I do know the list server was offline for more
> than a day while the changes went in, so it was less than trivial.
> The only real change I can detect from looking at mail headers is that
> it seems the list may now be attaching its own DKIM-Signature header
> to emails that had one upon arrival.
>
> If anyone thinks we might be motivated to become DMARC compliant,
> I can inquire for more details. But I won't bother unless there's
> real interest.
>
>
I'd definitely be interested at least in what they're doing. Whether we'd
actually implement it would depend on the implications of course, but if
they've actually figured out how to do it, it could be useful.

We've discussed just forcibly stripping the DKIM headers of those emails,
but that's unlikely to help - I'm sure large mail providers will "know"
that yahoo mail is supposed to carry DKIM and thus fail. The whole point of
DKIM is to prevent changing the headers after all - and we do change the
headers.

Yahoo has a page on it (can't find the ref this moment) where they simply
say "there is no mailinglist software supporting this. There are some
experimental patches for an old version of mailman that people will perhaps
consider merging at some time in the future."

--
Magnus Hagander
Me: http://www.hagander.net/
Work: http://www.redpill-linpro.com/