On Apr 10, 2014, at 03:09 PM, Siniša Burina wrote: >I believe there's no need to elaborate on the problems recently introduced by >Yahoo, changing their DMARC DNS record and rendering many mailman lists >unusable for Yahoo mail users.
It *is* a shame that these anti-spam defenses knowingly break mailing lists. I say "knowingly" but not "maliciously" because their specs usually describe the adverse affects on mailing lists, along with some mitigation approaches (which may not have a positive effect on list usability <wink>). The spec authors are not hostile to mailing lists and would rather not break them, but there does seem to be a fundamental conflict between mailing lists and anti-spam approaches. That said, DMARC was discussed in great detail last year on the -developers list, so if you want all the gory details, check out those archives. Mark will probably follow up in more detail, but MM2.1 implemented a feature in 2.1.16 called "from_is_list" which is a ternary option for addressing the effects of DMARC. It has to be enabled by the site admin, and then list admins can opt-in. It's disabled by default for backward compatibility reasons. From Defaults.py: # The following is a three way setting. # 0 -> Do not rewrite the From: or wrap the message. # 1 -> Rewrite the From: header of posts replacing the posters address with # that of the list. Also see REMOVE_DKIM_HEADERS above. # 2 -> Do not modify the From: of the message, but wrap the message in an outer # message From the list address. DEFAULT_FROM_IS_LIST = 0 So as you can see, two approaches are available, From: rewriting or outer message wrapping. Both are suboptimal for usability, but it seems like we have no other viable option. This is not yet implemented in MM3 because I don't really like having to do it. We might have no choice though. -Barry ------------------------------------------------------ Mailman-Users mailing list Mailman-Users@python.org https://mail.python.org/mailman/listinfo/mailman-users Mailman FAQ: http://wiki.list.org/x/AgA3 Security Policy: http://wiki.list.org/x/QIA9 Searchable Archives: http://www.mail-archive.com/mailman-users%40python.org/ Unsubscribe: https://mail.python.org/mailman/options/mailman-users/archive%40jab.org
