Copyright © 2001-2007 Thomas M. Eastep
Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2 or any later version published by the Free Software Foundation; with no Invariant Sections, with no Front-Cover, and with no Back-Cover Texts. A copy of the license is included in the section entitled “GNU Free Documentation License”.
2007-04-01
Glossary
What
is Shorewall?
Current Shorewall Releases
Getting Started with
Shorewall
Looking for Information?
License
Netfilter - the packet filter facility built into the 2.4 and later Linux kernels.
ipchains - the packet filter facility built into the 2.2 Linux kernels. Also the name of the utility program used to configure and control that facility. Netfilter can be used in ipchains compatibility mode.
iptables - the utility program used to configure and control Netfilter. The term 'iptables' is often used to refer to the combination of iptables+Netfilter (with Netfilter not in ipchains compatibility mode).
The Shoreline Firewall, more commonly
known as "Shorewall", is a 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 utility,
Shorewall configures Netfilter 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; as a consequence,
Shorewall can
take advantage of Netfilter's connection state tracking
capabilities to create a stateful firewall.
Shorewall is not a daemon. Once Shorewall
has configured Netfilter, it's job is complete and there is
no Shorewall code left running in the system. The /sbin/shorewall
program can be used at any time to monitor the Netfilter firewall.
Shorewall is not the easiest to use of the available iptables configuration tools but I believe that it is the most flexible and powerful. So if you are looking for a simple point-and-click set-and-forget Linux firewall solution that requires a minimum of networking knowledge, I would encourage you to check out the following alternatives:
m0n0wall (FreeBSD Based)
On the other hand, if you are looking for a Linux firewall solution that can handle complex and fast changing network environments then Shorewall is a logical choice.
To see some of the many things that
you can do with Shorewall, see the Shorewall
Features page.
The current
Stable Release version
is 3.4.2
New to Shorewall? Download the current Stable version (see above) then select the QuickStart Guide that most closely matches your environment and follow the step by step instructions.
The Documentation Index is a good place to start as is the Site Search in the frame above.
This program is free software; you can redistribute it and/or modify it under the terms of Version 2 of the GNU General Public License as published by the Free Software Foundation.
This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more detail.
You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA
Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2 or any later version published by the Free Software Foundation; with no Invariant Sections, with no Front-Cover, and with no Back-Cover Texts. A copy of the license is included in the section entitled "GNU Free Documentation License".
LEAF is an open source project which provides a Firewall/router on a floppy, CD or CF. Several LEAF distributions including Bering and Bering-uClibc use Shorewall as their Netfilter configuration tool.
OpenWRT is a project which provides open source firmware for Linksys WRT54G wireless routers. Two different Shorewall packages are available for OpenWRT.
Shorewall
is free but if you try it and find it useful, please consider making
a donation to the Alzheimer's
Association or to the Starlight
Children's Foundation.
Thank You