Network monitoring, access control & booby traps using TCP Wrappers: Part 1
Will opens the door to success.
- Louis Pasteur
What according to you would be the best way to fortify your machine from the anarchy of the Internet? Let's look at a few options.
You could put in a well configured firewall. Though this is quite a complex procedure, it's worth going through the pain. And there will be pain. Putting down your organizational policies and framing rulesets that keep the bad guys out and lets the good guys in, requires a lot of thinking on your part. Experience has taught us to verify our rulesets again and again, because even one slip during the framing of the rulesets can bring the house down. At the end of the day, you'll be the only punching bag around.
You could be too lazy to have any security measures in place. You justify this by saying that among the millions of machines out there, you're not going to be hit.
You could be totally paranoid about security concerns on the Internet. Securing yourself from the Internet is a simple affair of disconnecting your machine from the network. But then, you wouldn't be reading this article.
You could put security measures in place that GRANT or DENY access to various services on your machines depending on the privileges that you have setup using TCP Wrappers. TCP Wrappers by itself isn't a complete solution as far as securing you machine is concerned. But it does fit into the overall scheme of framing a security policy for your enterprise.
In this first part of the series, we will be introducing to you the whole concept surrounding the working of TCP Wrappers. We will leave out the implementation part for later. For now, we will help you get a foot hold on the use and importance of TCP Wrappers on a Linux/UNIX system. One more point that comes to mind, and which warrants clarification is the uniformity of concept that we are dealing with in relevance to the various UNIX operating systems . Of course, the procedure of implementation of the TCP Wrapper differ across various Unix systems, but we can assure you that if can find yourself GCC/G++ for your Unix machine, there's no stopping you from implementing this latest version of TCP Wrappers on your machine.
Getting down to business .....