On Sun, 2010-08-01 at 14:07 +0100, Nigel Metheringham wrote: > On 1 Aug 2010, at 13:43, Jeremy Harris wrote: > > > Are you assuming that > > header From: is the same as envelope MAIL FROM ? > > By the way, don't take that as a suggest you should be checking header > From: - for a reason why look at messages you sent to this mailing > list as they come back to you...
Well, in the general case it's just as broken to do it on the envelope MAIL FROM:. Some "mailing lists" turn out to be just aliases which expand to a bunch of people, and don't rewrite the envelope sender either. I noticed a few days ago that the Fedora packager-sponsors list is an example of this, for example. So if one of your users sent a message to such a "list", you'd reject that message. So none of your other users would receive it (and neither would the original sender, of course). You'd also reject valid messages if you have users who forward an external mail account to their account on your server. If any of your local users then send mail to that account, it's going to come back to you, quite correctly, with your *own* sender address in the envelope. And get wrongly rejected. You cannot safely reject mail based on comparing the MAIL FROM: address with the IP address from which it comes. You'd do better to look at BATV -- where you can reject the message based on the MAIL FROM: address *alone*. For example, I never send MAIL FROM:<[email protected]> and thus I can reject all messages with that in the envelope, regardless of where they come from. -- dwmw2 -- ## List details at http://lists.exim.org/mailman/listinfo/exim-users ## Exim details at http://www.exim.org/ ## Please use the Wiki with this list - http://wiki.exim.org/
