Free virus protection for computers software for linux

Your computer has been invaded! Dozens of little viruses are pouring in via security holes in Microsoft Internet Explorer, Microsoft Outlook, Microsoft MSN Messenger and Microsoft Recycle Bin!!
Using your trusty mouse you must shoot the buggers before they can destroy your files! Some will steal them from their home directories and take them back to their security hole.
Others will just eat them right there on the spot! See how long you and your computer can survive the onslaught!
Main features:
- 3 different virus types.
- Builds directories and files to protect based on your computer!
- Increasing difficulty level
- Highscore table
- 3 difficulty settings

AntiVirus Scanner is an anti-virus scanner for Endeavour Mark II that uses the ClamAV library (libclamav).

AntiVirus Scanner allows you to create a list of scan items for frequently scanned locations and features easy virus database updating, all in a simple GUI environment.

Aegis project is a virus scanner for Linux, Unix and Windows with a simple and intuitive user interface.

Aegis supports scanning of subdirectories, hidden files and .zip and .tar archive files, and drag-and-drop of files from the Nautilus file browser, or your Gnome desktop. When a virus is detected you can choose to delete, quarantine or rename the file.

HAVP (HTTP Antivirus Proxy) is a proxy with a ClamAV anti-virus scanner. HTTP Anti Virus Proxy aims are continuous, non-blocking downloads and smooth scanning of dynamic and password protected HTTP traffic.
Havp antivirus proxy has a parent and transparent proxy mode. It can be used with squid or standalone.
Main features:
- HTTP Antivirus proxy
- Scans complete incomming traffic
- Nonblocking downloads
- Smooth scanning of dynamic and password protected traffic
- Can used with squid or other proxy
- Parent proxy support
- Transparent proxy support
- Logfile
- Process change to defined user and group
- Daemon
- Use Clamav (GPL antivirus)
- Operating System: Linux
- Written in C++
- Released under GPL
Enhancements:
- Experimental support was added for chunked Transfer-Encoding, which fixes some broken sites.
- The IGNOREVIRUS configuration directive was added for whitelisting virus names.
- The CLAMBLOCKBROKEN configuration directive was added.
- Detection with AVG was improved.
- HAVP is killed if database reloading fails for Library Scanner.
- The URL is logged when a crashed scanner process is detected.
- The build system updated, adding the --prefix, --sbindir, --sysconfdir, and --localstatedir options.

POP3 Virus Scanner Proxy is a full-transparent proxy daemon which scans all mails for viruses using third party scanners (built-in support for AVPD and Trophie).

You have to set up a port redirection in the linux-netfilter (iptables) so that all connections from e.g. inside your office to any POP3 server outside in the world will not leave your router, but come a local port, on which POP3VScan listens. POP3VScan receives from the linux kernel the original destinations of packets (the POP3 server outside in the world) and will connect to them.

All data we receive from the client will be sent to the server, and vice versa. With a little enhancement: we parse the neccessary parts of the POP3 protocol and when an email is sent from the server, we store it into a file, invoke a virusscanner and send it if it is good, or we just replace it with a virus notification. It should be possible to use all scanners using the scannertype=basic. Also POP3VScan provides scannertype=avpd for high-speed scanning using Kaspersky Anti-Virus for Linux, every C programmer can easily adept other scan-daemons (trophie, sophie, antivir, ...).

Neither the client nor the server has to be configured, none of them will take notice that theres a mailscanner (except the client when he gets a virus notification or if he looks into the header, and the server gets our ip as source).

Firestarter is a firewall tool for Linux, and uses GNOME. You can use the wizard to create a basic firewall, then streamline it further using the dynamic rules.
You can open and close ports with a few clicks, or stealth your services giving access only to a select few.
It features a real-time hit monitor which you can watch as attackers probe your machine for open ports.
Main features:
- Open Source software, available free of charge
- User friendly, easy to use, graphical interface
- A wizard walks you through setting up your firewall on your first time
- Suitable for use on desktops, servers and gateways
- Real-time firewall event monitor shows intrusion attempts as they happen
- Enables Internet connection sharing, optionally with DHCP service for the clients
- Allows you to define both inbound and outbound access policy
- Open or stealth ports, shaping your firewalling with just a few mouse clicks
- Enable port forwarding for your local network in just seconds
- Option to whitelist or blacklist traffic
- Real time firewall events view
- View active network connections, including any traffic routed through the firewall
- Advanced Linux kernel tuning features provide protection from flooding, broadcasting and spoofing
- Support for tuning ICMP parameters to stop Denial of Service (DoS) attacks
- Support for tuning ToS parameters to improve services for connected client computers
- Ability to hook up user defined scripts or rulesets before or after firewall activation
- Supports Linux Kernels 2.4 and 2.6
- Translations available for many languages (38 languages as of November 2004)