netfilter query
 

how can i use packets in userspace using netfilter. i want some sample examples that manipulates on packet.

iptables -A INPUT -p tcp --dport 22 -j DROP ?

for more tutorial and howtos about the art of firewalling using iptables point your browser to www.netfilter.org

and here is a nice introduction to iptables
http://www.spotswood-computer.net/pr...iptables2.html

and this is best tutorial about iptables firewalling

http://iptables-tutorial.frozentux.n...-tutorial.html