Table of Contents
Barnyard2 is a way to store and process the binary outputs from Snort into a MySQL database.
Before we begin
https://www.itweb.services/tutorials/linux-guides/how-to-configure-snort-on-debian”>installing snort on debian systems. You must have snort installed in order for this system to work.
Update, Upgrade, and Reboot
Before we actually get our hands into the Snort (S) sources, we need to make sure our system is up to date. We can do this by issuing the commands below.
sudo apt-get update sudo apt-get upgrade -y sudo reboot
If you don’t have MySQL installed you can install it with the following command,
sudo apt-get install -y mysql-server libmysqlclient-dev mysql-client autoconf libtool
Setting up Barnyard2
In order to install Barnyard we need to grab the source from Barnyard2’s github page.
cd /usr/src sudo git clone https://github.com/firnsy/barnyard2 barnyard_src cd barnyard_src
Now that we have the source for barnyard we need to
sudo autoreconf -fvi -I ./m4
Update system library references
Once that is finished have to make a symlink to the dumbnet library as dnet.
sudo ln -s /usr/include/dumbnet.h /usr/include/dnet.h
Because we essentially made a new system library we have to update the system’s library cache. This can be done by issuing the following command:
Configuring Barnyard2 for MySQL
This part is important because it depends on whether or not your system is a 64 bit system or a 32 bit system.
If you are unsure as to whether or not your system is 64 bit or 32 bit, you can either use
uname -m or
arch to achieve this.
cd /usr/src/barnyard_src ./configure --with-mysql --with-mysql-libraries=/usr/lib/YOUR-ARCH-HERE-linux-gnu
So that configuration should look like
./configure --with-mysql --with-mysql-libraries=/usr/lib/x86_64-linux-gnu
make sudo make install
In order to set up barnyard properly and let it work with our system we need to copy over our configuration files. Also, please note, while I tested this I had to create the log directory for barnyard2 otherwise running it would fail.
sudo cp etc/barnyard2.conf /etc/snort sudo mkdir /var/log/barnyard2 sudo chown snort.snort /var/log/barnyard2 sudo touch /var/log/snort/barnyard2.bookmark sudo chown snort.snort /var/log/snort/barnyard2.bookmark
Creating the database
Now that our barnyard instance has been mostly set up we need to create and associate a database with our setup.
mysql -u root -p create database snort; use snort; source /usr/src/barnyard_src/schemas/create_mysql CREATE USER 'snort'@'localhost' IDENTIFIED BY 'MYPASSWORD'; grant create, insert, select, delete, update on snort.* to snort@localhost; exit;
Configuring barnyard for use with MySQL
In case you didn’t happen to change the password in the above command, you can reset the password by re-entering the mysql command and entering
SET PASSWORD FOR 'snort'@'localhost' = PASSWORD( 'MYPASSWORD' );
At the very bottom of your
/etc/snort/barnyard2.conf file add the following and edit the password to what you set above.
output database: log, mysql, user=snort password=MYPASSWORD dbname=snort host=localhost
For security purposes, we need to lock down our barnyard.conf file because it contains your database password in cleartext.
sudo chmod o-r /etc/snort/barnyard2.conf
You can test snort by having it run in alert mode using your config file.
sudo /usr/local/bin/snort -q -u snort -g snort -c /etc/snort/snort.conf -i eth0
Once snort is running, open another terminal and ping that system’s address, you should be able to see the messages on your main terminal.
Now that you have some data in your snort logs, you should be able to test barnyard against it.
sudo barnyard2 -c /etc/snort/barnyard2.conf -d /var/log/snort -f snort.u2 -w /var/log/snort/barnyard2.bookmark -g snort -u snort
These flags basically mean the following.
-c specifies the config file. -d is the snort output directory -f specifies the file to look for. -w specifies the bookmark file. -u / -g tells barnyard to run as a specific user and group.
After starting barnyard, once
Waiting for new data appears you can quit the application by pressing
ctrl + c now to check your MySQL database by logging back into the MySQL server and selecting all from the
event table in your
mysql -u snort -p snort select count(*) from event;
As long as the count is more than 0 everything worked properly!
However, if the count IS 0, you’re probably either pinging your system from a system that matches a whitelisted ip. If that is the case, try pinging your system from out side your network and to make sure that is exposed to the outside world.
Congratulations, you now have a way to read and keep track of your detected intrusions.
Do you need help setting up this on your own service?
Please contact us and we’ll provide you the best possible quote!