I have a somewhat unique requirement here for one test that we're going to perform. I need to block relaying for a specific sender. I'm wondering if there is a way to do that using stock qmail-ldap or I will need some extra tools for that? I just can't really think of anything at the moment, tcpserver can only go by IP addresses, so it's not exactly what I need. One thing I thought of is using RELAYCLIENT to append value to recipient address and that appended value would be some local domain. Essentially creating a redirect. But that's not what I really want, because that would affect every sender, not just this particular sender.
Can you get this "sender" to send from a particular IP address? You say it is an "automated system" so I wonder if that is not possible? If so then you could utilize RELAYCLIENT to make it work.
Yes, it's automated system, but it is distributed and IP addresses may change. So, it's not practical to handle this via RELAYCLIENT.
If that isn't an option, maybe you could set maildrop up on your qmail-ldap server and have incoming mail filtered in such a way that if your sender is the From: header (or envelope sender) and the To: header is set to a non-local recipient it is discarded. I dunno, not an ideal solution, but maybe it would work.
Umm. I will need to check this out. I suspect maildrop would be too cumbersome to deal with.
I'm actually thinking that qmail-queue wrapper of some sort would be better suited for this. I will have to do some reading today to find out what can and can't be done this way.
Can you set up another instance of qmail that would be configured to only accept local deliveries and send you mail through that?
No, I can't. That's the problem :)
