Fredrik Johnsson wrote: > > Hi! > > First I'm not subscribed to this list, and my question might not even applly > to this list (in that case I appologice). > > I'm about to set up a linux pased packetfiltering router and would like to > transparently filter mail (removing mail with bad attachments and spam), > without needign to replace the MX pointer. > > I'd like to filter the mail in both directions. > > Is it possible to filter the mail directly in iptables?
No. iptables is a packet filter - it filters network packets based on properties of those packets. It does not really know what those packets contain. In a gross oversimplification, you have a stream of cars and you want to prevent certain people from reaching you. The problem is that iptables can only blocks cars and not people - so it can prevent all Peugeots from reaching you, while letting Fiats through. But what you want is to stop all salesmen in those cars. iptables cannot help there. What you need is a cop or a receptionist who will find out what those people want from you and then let them through or turn them away. Look at TMDA, or ASK (see the link at the bottom of my sig) or any of the rbl folks like www.ordb.org for spam filtering. --Yan -- Future fighter pilots: Me: Akari, WHAT are you DOING? Akari, age 3: Pushing the envelope. spam killer code kpwq1jkcsEzdx39gnkVvgycd15ayqq (see http://www.paganini.net/ask)
