Spam mail tarpitting
OpenBSD came with something called spamd which can be used to tarpit incomming mail connections based on an IP list. I used spews as my IP list plus my own personal lists, with overriding whitelists for every IP I got regular non-spam mail from.
I would like to do the same for my linode.
There are hundreds of ways of filtering mail, or dropping mail connections. I don't want these, I want to tarpit the spammers. Anyone know how to do this with linux?
I'm sure I can figure out the iptables bit, but I still need the spamd daemon to deal with connections from offending IPs.
2 Replies
Packet filter redirected connections to port 25 from known netblocks before the MTA even got wind of them. I can do that bit with iptables, What I don't have is a daemon to do the tarpitting after the connection is redirected.
I could use DNS blacklisting to refuse connections, but I don't want to refuse them, I want to waste their resources.