[ILUG] sendmail and filters
barry.redmond at cs.tcd.ie
Wed Jan 30 14:11:02 GMT 2002
(With DIT hat on)
A smallish mail server that I manage is seeing a lot of junk mail of a
particular form coming in, and I want to try to block it without spending
days wandering lost in sendmail's config files. I once understood a
little bit about sendmail, but those brain patterns decayed a long time
ago and I have no inclination to train replacements. Now I just turn
sendmail features on and off.
The junk mail comes from different sources because it's being
"returned" from non-existant destination addresses. The return
address is always a real address (different each time) on one of our
systems, but with 6 apparently random digits appended to the
username. Is there any *easy* way to insert a filter that can apply a
regular expression to parts of a header as the mail is coming in, and
give a reject/accept decision?
I already use a realtime blackhole list, and block some specific junk
addresses, but this case needs a finer mechanism.
More information about the ILUG