Nick Gregory, a Sophos threat researcher, found this hole recently while checking netfilter for possible security problems. Gregory explains in great detail his bug hunt, and I recommend it for those ...

When deciding on a firewall implementation, most Unix-savvy administrators have usually chosen to use ipfilter on OpenBSD for their combination of capabilities and stability, as the capabilities of ...

Linux 2.4's Netfilter firewall code and its front end, iptables, deserve the praise and popularity they've garnered. They've brought Linux firewalls to the same level as commercial stateful ...

The Linux kernel includes some of the most powerful and flexible firewall code in any general-purpose operating system. This code is called Netfilter, though most of us refer to it by the name of its ...

I'm looking to write a Perl program to monitor my network services for intrusion and DOS attempts. I want to take advantage of the INSERT and DELETE options of the "iptables" command. I was hoping ...

WHEN LOOKING for an effective, inexpensive firewall solution, Linux firewalls do not often enter into the picture unless someone involved in the security planning process is a Linux guru. With the ...

This chapter looks at the management of firewalls. From the perspective of the small office/home user, the firewall is a single device that protects the home network from malicious traffic—it keeps ...

In today's open source roundup: Six GUI firewall management applications in Linux. Plus: Linux Lite 2.2 released, and the story of how Kali Linux was created The command line is a powerful tool for ...