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The release of Ubuntu Dapper 6.06 caused a lot of buzz even before it


Under... SELinux standing !

Security-enhanced Linux (SELinux) is an implementation of a mandatory access control (MAC) mechanism. This mechanism is in the Linux kernel, checking for allowed operations after standard Linux discretionary access controls are checked.
Standard Linux security is a discretionary access control model (DAC).

Discretionary access control (DAC)

DAC is standard Linux security, and it provides no protection from broken software or malware running as a normal user or root.


What does Exploit means ?
Exploit is a very small program that when utilized causes a software vulnerability to be triggered and leveraged by the attacker.

What does Buffer Overflows means ?
Buffer Overflow occurs when a buffer that has been allocated a specific storage space has more data copied to it than it can handle.

So...
Have you checked your server's log files lately ???
Did you notice something like... this !!!

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).


As previously announced in an ealier article, I have finally completed the migration of my laptop from Debian Etch to Fedora Core 5.

I would like to write about it and my impressions after 5 days of using Fedora.

Fedora Core comes in a set of 5 CD-Roms, but you can install it from the net. I chose the first option, and it is important to actually have the 5 CDs ready for the installation (contrary to what one guy told me earlier). The installation  was a breeze. Anaconda, the graphical installer, is a little bit less good-looking than the SuSE or Mandriva installers, but its even more effective.


As announced on my blog , I will soon move from my beloved Debian etch (or testing) to the upcoming Fedora Core 5.

How did I come to take such a decision?
I love several things in Debian. I run a Debian etch on my laptop, my old PC runs a Windows 2000 unconnected to the Net and is used for gaming; my company's servers run on Debian sarge except for the webserver, hosted somewhere else that run a nicely tuned Free BSD. Debian to me means the experience of one of the most authentic GNU and Free Software systems and in some sense, lifestyle.


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"


The idea that you could just change the way your computer's user interface looks like and behaves is pretty foreign to most people that typically use Windows or Apple's OSX.


Sometimes you might run into an internet radio station or stream that you like, but which keeps dropping out because of too many people listening. So what can you do about it?