Isowall is a mini-firewall that allows you to completely isolate a device from the local network. This is for allowing infected machines Internet access, but without endangering the local network.
This project depends upon libpcap, and of course a C compiler.
On Debian, the following should work:
# apt-get install git gcc make libpcap-dev
# git clone https://github.com/robertdavidgraham/isowall
# cd isowall
This will put the binary isowall in the local isowall/bin directory.
This should also work on Windows, Mac OS X, xBSD, and pretty much any operating system that supports libpcap.
First, setup a machine with three network interfaces.
The first network interface (like eth0) will be configured as normal, with a TCP/IP stack, so that you can SSH to it.
The other two network interfaces should have no TCP/IP stack, no IP address, no anything. This is the most important configuration step, and the most common thing you’ll get wrong. For example, the DHCP software on the box may be configured to automatically send out DHCP requests on these additional interfaces. You have to go fix that so nothing is bound to these interfaces.
To run, simply type:
# ./bin/isowall --internal eth1 --external eth2 -c xxxx.conf
The following shows a typical configuration file
internal = eth1
internal.target.ip = 10.0.0.129
internal.target.mac = 02:60:8c:37:87:f3
external = eth2
external.router.ip = 10.0.0.1
external.router.mac = 66:55:44:33:22:11
allow = 0.0.0.0/0
block = 192.168.0.0/16
block = 10.0.0.0/8
block = 22.214.171.124-255.255.255.255
You can download isowall here: