Full description
The Shoreline Firewall, more commonly known as "Shorewall", is high-level tool for configuring Netfilter. You describe your firewall/gateway requirements using entries in a set of configuration files. Shorewall reads those configuration files and with the help of the iptables, iptables-restore, ip and tc utilities, Shorewall configures Netfilter and the Linux networking subsystem to match your requirements. Shorewall can be used on a dedicated firewall system, a multi-function gateway/router/server or on a standalone GNU/Linux system. Shorewall does not use Netfilter's ipchains compatibility mode and can thus take advantage of Netfilter's connection state tracking capabilities. Shorewall is not a daemon. Once Shorewall has configured the Linux networking subsystem, its job is complete and there is no "Shorewall process" left running in your system. The /usr/sbin/shorewall program can be used at any time to monitor the Netfilter firewall.