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vi survival guide


1. Introduction
2. Basic crash course


I have always been interested in Linux distributions and how they evolve, not just technically, but also in terms of their popularity and their -wanted or unwanted- position among the Linux users and on the broader market.
In this regard, the Distrowatch web site is a fairly effective tool at tracking linux distributions no matter how small or short-lived they are. I think the site's online tool is actually the best one so far, and it has, in my opinion, produced the best stats concerning Linux distributions, unless you consider the NetCraft surveys but these are confined to the web servers' world. Distrowatch takes all of them, servers, desktop, set top boxes, and now has come to include OpenSolaris and BSD Unixes. It spans over 100 distributions, although there are more (but then these are dead or fairly underground distros).


Recently, I wrote an article about How to scan your Linux-Distro for Root Kits.
Now that the machine is... clean! I think, a good thing TO-DO, is to test my Firewall (AGAIN !!!)
The good news are that we can use the free tool FTester.
The bad news are that FTester needs to be configured right...

So... Let's get to work !

What is FTester ?
The Firewall Tester (FTester) is a tool designed for testing firewalls filtering policies and Intrusion Detection System (IDS) capabilities.

The tool consists of two perl scripts, a packet injector (ftest) and the listening sniffer (ftestd).
The first script injects custom packets, defined in ftest.conf, with a signature in the data part while the sniffer listens for such marked packets.
The scripts both write a log file which is in the same form for both scripts.
A diff of the two produced files (ftest.log and ftestd.log) shows the packets that were unable to reach the sniffer due to filtering rules if these two scripts are ran on hosts placed on two different sides of a firewall.
Stateful inspection firewalls are handled with the 'connection spoofing' option.
A script called freport is also available for automatically parse the log files.

The IDS (Intrusion Detection System) testing feature can be used either with ftest only or with the additional support of ftestd for handling stateful inspection IDS, ftest can also use common IDS evasion techniques.
Instead of using the configuration syntax currently the script can also process snort rule definition file.

Features:
- firewall testing
- IDS testing
- simulation of real tcp connections for stateful inspection firewalls and IDS
- connection spoofing
- IP fragmentation / TCP segmentation
- IDS evasion techniques

Requirements:
The following perl modules are required: Net::RawIP, Net::PcapUtils, NetPacket

So... we will need the Net::RawIP , Net::PcapUtils, and NetPacket Perl modules. We may also need the Net::Pcap module if it is not already installed, because the Net::PcapUtils module depends on it.
If we have the CPAN Perl module, we may install these modules with the following commands from shell:
# perl -MCPAN -e "install Net::RawIP"


Welcome everyone to the beginnings of a new Nuxified.org web site! This site is now powered by Drupal, a powerful and highly extensible content management system and web development framework that just recently got it's newest and most amazing release which is of course now used here.

Thanks to Drupal we will be able to take this site in nearly any direction we would want. If we want a nice and functional articles system, it is already here. If we want to add something entirely unique, the tools to build it quickly are already available. No messy hacks that cause downtimes for every minor upgrade (which can often be the case with phpbb). With Drupal, everything should be possible and in a clean way.