Shorewall plugin


Install the packages python-mmc-shorewall and mmc-web-shorewall.

MMC « shorewall » plugin

THe shorewall plugin will manage the files in /etc/shorewall. The plugin is designed to manage internal and external interfaces. An external interface is generally connected to an insecure network (Internet), and internal interface is connected to a known/controlled network.

Typically if your server is installed in a datacenter and have a public interfaces to the Internet, they are external interfaces. If your server is in your local network you have only internal interfaces. A server acting as a gateway has generally one public interface and one interface interface.

Once your interfaces are defined as ‘internal’ or ‘external’ all the firewall configuration can be done from the MMC interface. Depending on your interfaces configuration you will be able to access more or less features. For example, if you have one internal and one external interface you will be able to create a NAT rule for your internal network.

Example of the shorewall plugin with two ‘internal’ interfaces:


MMC « shorewall » plugin configuration

Like every MMC plugin the configuration can be found in /etc/mmc/plugins/shorewall.ini

The plugin will assume that an interface is internal or external because of its zone name. By default if your zone begins by ‘lan’ (lan0, lanA ...) the interface will be considered as ‘internal’. If the zone name begins by ‘wan’, the interface is considered as ‘external’.

You can change theses names by changing the external_zones_names and internal_zones_names options.

Shorewall configuration

The initial shorewall configuration should be done manually. Check the shorewall docs for more information about shorewall configuratioon.

Example with a gateway (two interfaces, one internal, one external).

In /etc/shorewall/interfaces declare your network interfaces and associated zones:

lan0     eth0
wan0     eth1

In /etc/shorewall/zones declare your zones types:

fw      firewall
lan0    ipv4
wan0    ipv4

In /etc/shorewall/policy define the default policy between your zones:

fw      all     ACCEPT  # server -> anywhere
lan0    fw      DROP    # lan0 -> server
wan0    fw      DROP    # wan0 -> server
all     all     DROP    # catch-all rule

Finally, be sure that the file /etc/shorewall/rules exists