Gibraltar is a Debian GNU/Linux-based router/firewall distribution, fully workable from a bootable, live CD-ROM. Log files can be stored on a hard disk, and configuration data is stored on a USB mass storage media or a floppy disk and kept on a RAM disk during run-time. Due to its Debian base, a vast manifold of firewalling, routing, and proxy packages is available. It comes with an intuitive, easy to use Web administration interface and support, and is free to use for home users.
The Network Security Policy Compiler (NetSPoC) is a tool for security management of large computer networks with different security domains. It generates configuration files for packet filters controlling the borders of security domains. It provides its own language for describing security policy and the topology of a network. The security policy is a set of rules that state which packets are allowed to pass the network and which are not. NetSPoC is topology aware; a rule for traffic from A to B is automatically applied to all managed packet filters on the path from A to B.
Sshguard monitors services through their logging activity. It reacts to messages about dangerous activity by blocking the source address with the local firewall. Sshguard employs a clever parser that can transparently recognize several logging formats at once (syslog, syslog-ng, metalog, multilog, raw messages), and detects attacks for many services out of the box, including SSH, several ftpds, and dovecot. It can operate all the major firewalling systems, and features support for IPv6, whitelisting, suspension, and log message authentication.
Nulog is a PHP interface for the MySQL plugin for the ulogd netfilter log daemon and for NuFW SQL logging (optional). It displays hosts (or users) that recently broke packets on your firewall and the last ports that were probed. A simple search function allows packets to be searched by host or by a given port. Nulog was formerly known as ulogd-php.
redWall is a bootable CD-ROM firewall which focuses on Web-based reporting of the firewall's status. It includes Snort, snortsam, dansguardian, and support for fwbuilder, squidguard, reporting (using BASE/sarg/ntop/webfwlog), VPN (Openswan/PoPToP/Openvpn), Spam Filtering (spamassassin, dcc, razor2, clamav, amavis-new, dspam and maia mailguard), and mail-based, alerting. Configuration data are stored on a floppy or USB disk.
FireHOL a simple yet powerful way to configure stateful iptables firewalls. It can be used for almost any purpose, including control of any number of internal/external/virtual interfaces, control of any combination of routed traffic, setting up DMZ routers and servers, and all kinds of NAT. It provides strong protection (flooding, spoofing, etc.), transparent caches, source MAC verification, blacklists, whitelists, and more. Its goal is to be completely abstracted and powerful but also easy to use, audit, and understand.
OpenVPN is a robust and highly configurable VPN (Virtual Private Network) daemon which can be used to securely link two or more private networks using an encrypted tunnel over the Internet. OpenVPN's principal strengths include wide cross-platform portability, excellent stability, support for dynamic IP addresses and NAT, adaptive link compression, single TCP/UDP port usage, a modular design that offloads most crypto tasks to the OpenSSL library, and relatively easy installation that in most cases doesn't require a special kernel module.
IPTables-tutorial is a tutorial which explains how to install and set up iptables and netfilters on Linux. It takes you through a usable example file step by step, and helps you understand its basic functionality. The tutorial currently contains 6 different example scripts that may be used freely under GPL licensing terms.
BlockIt monitors the Snort alert file and creates either IPTables, IPChains, IPFWADM, IPFilter, PF, or Checkpoint Firewall rules. This version runs on Linux, FreeBSD, and OpenBSD. BlockIt has built-in CIDR support for multiple target IPs and whitelist support. Additional features include MySQL logging and email logging.