Netfilter is a powerful packet filter implemented in the standard Linux kernel. The userspace iptables tool is used for configuration. It now supports packet filtering (stateless or stateful), all kinds of network address and port translation (NAT/NAPT), and multiple API layers for 3rd party extensions. It includes many different modules for handling unruly protocols such as FTP.
netfilter is a set of hooks inside the Linux kernel that allows kernel modules to register callback functions with the network stack. A registered callback function is then called back for every packet that traverses the respective hook within the network stack. iptables is a generic table structure for the definition of rulesets. Each rule within an IP table consists of a number of classifiers (iptables matches) and one connected action (iptables target).
- stateless packet filtering (IPv4 and IPv6)
- stateful packet filtering (IPv4 and IPv6)
- all kinds of network address and port translation, e.g. NAT/NAPT (IPv4 and IPv6)
- flexible and extensible infrastructure
- multiple layers of API's for 3rd party extensions
Download Here :: git clone git://git.netfilter.org/iptables.git
Official Website :: http://www.netfilter.org/