Compiling Suricata 0.8.2 in Ubuntu Lucid 10.04 in IDS mode

The newly released Ubuntu Lucid 10.04 LTS looks like a good platform for running an IDS on. It’s up to date and has long term support. Here is how to compile and install Suricata 0.8.2 on it.

Install the following packages needed to build Suricata: libpcre3-dev libpcap-dev libyaml-dev zlib1g-dev.

apt-get install libpcre3-dev libpcap-dev libyaml-dev zlib1g-dev

Download Suricata 0.8.2 here

Extract the suricata-0.8.2.tar.gz file as follows:

tar xzvf suricata-0.8.2.tar.gz

Enter the extracted directory suricata-0.8.2.

Run “./configure”
Note that you may get a warning about libnet 1.1 that is missing. You can ignore that, it’s only used in IPS/inline mode currently.
If “./configure” was succesful, run “make”
If “make” was succesful, run “sudo make install”
Except for Suricata itself, the build process installed “libhtp”. For that to work properly, run “ldconfig”.

Run “suricata -V” and it should report version 0.8.2.

To use Suricata in IDS mode, pass -i to the command line. Example

suricata -c /etc/suricata/suricata.yaml -i eth0

Fixing noise on Ubuntu Hardy 8.04, aka setting max_cstate

Not security related at all, but it took me so much time to figure this out, I want to share this with the world!

I own a Lenovo Thinkpad T60 that I like very much. There is one annoyance, and that is that when on battery, the laptop produces a high pitched noise when idle. It turns out that this has something to do with the ACPI state. States of C3 and higher made my laptop produce the noise. In Ubuntu Gutsy 7.10 there was a simple solution. I could force the laptop to never use anything higher that C2. That was done like this:

echo “2” > /sys/module/processor/parameters/max_cstate

And everyone was happy! Noise gone, battery life still decent. All was good. Until I upgraded to Hardy. Hardy uses kernel 2.6.24, and for some reason the sysfs interface has been removed. So there is no way to set the max_cstate on the fly. See here for the bug report.

In theory the ‘processor’ module should be able to take an option ‘max_cstate=2’. But setting this option didn’t seem to work. It took some time to figure out why, but the reason is simple. The ‘processor’ module is in the initrd image, and is loaded before /etc/modprobe.d/options is inspected. Luckily, the solution is simple:

Add the following line to your /etc/modprobe.d/options file:

options processor max_cstate=2

Then update the initrd image using the following command:

sudo update-initramfs -u

The initrd image is now updated to include the option. Then reboot. Verify if it works:

$ cat /proc/acpi/processor/CPU0/power |grep max_cstate
max_cstate:              C2

Success! Again, no more noise…

Update 21st of March 2010 for Ubuntu Karmic 9.10. The solution for this for Karmic was posted by Markus in the comments below, I’m replicating it here for convenience. Thanks Markus!

Karmic introduces the new grub2 so there isn’t any menu.lst anymore. In grub2 some things (like default kernel options) are done in /etc/default/grub, so you have to edit this file:

sudo pico /etc/default/grub

search for a line GRUB_CMDLINE_LINUX=”” and change to (or add if it doesn’t exist):


press STRG+x and y to save and exit and execute the grub update:

sudo update-grub

After a reboot the max cstate should then be C2!

Sguil 0.7-CVS client on Ubuntu Gutsy

Last week I installed Ubuntu Gutsy on my laptop. I did a clean install, which went fine. Of course, I needed the Sguil client on it as well. Gutsy has all the required libraries in it’s repositories. Install the following packages:


Checking out the Sguil client is easy (make sure you have ‘cvs’ installed):

cvs login
cvs co sguil

After this the client runs fine on my system.

Vuurmuur developments

Last weeks I’ve spend many hours on my Vuurmuur Firewall project. First I’ve been improving the code to prepare for a new release. I’ve added NFQUEUE support to Vuurmuur, so I could use it with nfnetlink enabled Snort_inline. Also the connection killing has been improved. The rules limit options were extended, to allow more flexibility.

Second, with the great help of Adi Kriegisch, I’ve been working on setting up a new build server for Debian and Ubuntu packages. Credits mostly go to Adi, who did most of the work and hosts the server. So many thanks to Adi! The new build server supports all version of Debian from Sarge up and of Ubuntu from Dapper and up.

Third, I have been busy setting up a new site for Vuurmuur. It is based on the Trac software and replaces both the static site at and the tikiwiki based wiki. The new site can be found at

Last but not least, and the reason for this post, is that today I’ve released a new version of Vuurmuur. The version, 0.5.73, is the first non-test release since January. This has taken a lot longer than I wanted, but work and other projects and of course ‘real life’ have taken much of the time from Vuurmuur. I don’t think this will change any time soon, unless someone will join the project to contribute some serious amount of coding time, or someone wants to fund me to do so.

On the roadmap (which is a nice feature of Trac btw) one can see the future directions of Vuurmuur. Ideas and comments are welcome. So are bug reports of course 🙂

Update on Sguil 0.7-CVS client on Ubuntu Feisty

A short time ago I wrote about how the Sguil 0.7-CVS client can be installed on Ubuntu Feisty. Since then there has been a change to Sguil that changes the requirements a bit. Because of this the standard tcllib package in Feisty is no longer usable. It provides tcllib 1.8 while Sguil now needs 1.9. Luckily, we can use the tcllib package from the upcoming Ubuntu release called ‘Gutsy’. It can be found here:

I installed it with this command:

$ sudo dpkg –install tcllib_1.9.dfsg1-1_all.deb

This made Sguil 0.7-CVS work again on my system.

Compiling Snort_inline with NFQUEUE support on Ubuntu

I needed to setup the right libraries for Snort_inline development on my fresh Ubuntu Feisty installation, so I decided to write down the procedure for those who think compiling Snort_inline from source is hard. 🙂

Make sure you have build-essential package installed. This makes sure you have a compiler and development packages for glibc and other important libraries. I’m installing the libraries from source to get the latest versions because the latest versions are more stable and perform better than the versions included in Feisty. I’m installing them into /usr because some programs like them there best.

Download the library libnfnetlink version 0.0.25 from

$ tar xvfj libnfnetlink-0.0.25.tar.bz2
$ cd libnfnetlink-0.0.25/
$ ./configure --prefix=/usr
$ make
$ sudo make install

Next download libnetfilter_queue version 0.0.13 from

$ tar xvfj libnetfilter_queue-0.0.13.tar.bz2
$ cd libnetfilter_queue-0.0.13
$ ./configure --prefix=/usr
$ make
$ sudo make install

Okay, that sets up the Netfilter libraries.

Next is the installation of libdnet. Do not use the dnet packages from Debian and Ubuntu because this is not the same library as we need for Snort_inline.

Download libdnet 1.11 from

$ tar xzvf libdnet-1.11.tar.gz
$ cd libdnet-1.11
$ ./configure --prefix=/usr
$ make
$ sudo make install

Download snort_inline from

$ tar xvzf snort_inline-
$ cd snort_inline-
$ ./configure --enable-nfnetlink
$ make
$ sudo make install

Test if it works (as root):

# iptables -A OUTPUT -p icmp -j NFQUEUE
# iptables -A INPUT -p icmp -j NFQUEUE
# /usr/local/bin/snort_inline -v -Q -H0

Then ping some host and you should see Snort_inline display the packets. If it doesn’t work, it might be that the kernel modules needed for nfqueue are not yet loaded. Using ‘lsmod’ check if ‘nfnetlink’ and ‘nfnetlink_queue’ are loaded. If not, load them manually.

After this, setup Snort_inline as normal.

Sguil 0.7-CVS client on Ubuntu Feisty

I just got a new workstation that I’m setting up today with Ubuntu Feisty 7.04. When setting up the Sguil client from CVS I needed to install the following packages (including dependencies, but apt-get takes care of that):


After this it ran but looked horrible because of some ugly font that was used. I found that for my use the following fonts look good:

standard: Bitstream Vera Sans 12
fixed: Bitstream Vera Sans Mono 12

Both fonts are installed by default and can be selected in the Sguil client by opening the ‘File’ dropdown menu and choosing ‘Change Font’.