GNet Solutions » GNU/Linux Administration

I have setup Snort on my router, however due to the flash based media for its OS there are constraints on log files size. The snort package on pfSense support Barnyard2, which is a MySQL interface to allow logs or alerts to be stored on a MySQL database, which is where Snorby comes in.

Snorby brings your existing and new network securits monitoring data to life with a suite of beautiful, relevant, and, most importantly, actionable metrics. Share data like sensor activity comparisons or your most active signatures directly with your constituents with daily, weekly, monthly, and ad-hoc PDF reports.

Snorby requires a LAMP stack with Ruby and Passenger installed, I have the LAMP stack already installed, however I will include the the packages in this tutorial to be comprehensive.

As a first step we’re going to install Snort. Luckily it’s up in the repos, so we’re just going to apt-get it. I’m going to go with the snort-mysql package, as it gives a mysql DB support to snort which is a good thing.

First let’s get a mysql server up and running:

apt-get update
apt-get upgrade
apt-get install mysql-server mysql-client

Then we can get snorby up:

apt-get install snort-mysql

This is needed to for a SQL schema file

This will ask a few questions and it doesn’t matter what you answer as we’ll have to reconfigure it after Snorby has been installed anyway.

Moving on to installing the Snorby prerequisites:

apt-get install libyaml-dev git-core default-jre imagemagick libmagickwand-dev wkhtmltopdf build-essential libssl-dev libreadline-gplv2-dev zlib1g-dev <linux-headers-686-pae> libsqlite3-dev libxslt1-dev libxml2-dev libmysqlclient-dev libmysql++-dev apache2-prefork-dev libcurl4-openssl-dev ruby ruby-dev

Don’t forget to use the linux headers for your kernel’s architecture…

Instal a few prerequisite gems:

gem install bundler rails 
gem install rake --version=0.9.2

Switch to the web directory:

cd /var/www/

Download the source for the application.

git clone http://github.com/Snorby/snorby.git

Change to the Snorby config directory:

cd /var/www/snorby/config/

Set up configuration files:

cp database.yml.example database.yml
cp snorby_config.yml.example snorby_config.yml
sed -i s/"\/usr\/local\/bin\/wkhtmltopdf"/"\/usr\/bin\/wkhtmltopdf"/g snorby_config.yml

Create snort database and user:

mysql -u root -p

CREATE DATABASE snort;
GRANT ALL PRIVILEGES TO 'snort'@'localhost' IDENTIFIED BY 'SuperSecretPassword';
EXIT

Tell snorby the mysql database name, user and password that it should use.

nano database.yml

At this point you should also create the user and the database.

Change into the Snorby directory:

cd /var/www/snorby/

Let’s install it:

bundle install --deployment
bundle exec rake snorby:setup

I encountered an error during this part, after googling a bit I found that a stale Gemfile.lock was the culprit and to solve it I needed to remove the .bundle directory then bundle install:

cd /var/www/snorby
rm -rf .bundle
bundle install
bundle exec rake snorby:setup

I also encountered a problem where I had to set the time in the config/snorby_config.yml

A third error was encountered where there was a dependency problem where bundler needed a version of activesupport that was not installed, to fix this I ran:

bundle update activesupport railties rails
gem install arel
gem install ezprint
bundle install
bundle exec rake snorby:setup

Yet another problem was encuntered during the installation:

rake aborted!
uninitialized constant Syck::Syck

Tasks: TOP => snorby:setup => environment

The fix was actually simple as well. Make sure the database in the database.yml file matches the database created earlier.

At this point Snorby should start when you type:

bundle exec rails server -e production -b 127.0.0.1

If you point your browser to
http://localhost:3000/
the Snorby WebUI should pop up.
You can access it with the default credentials:

• snorby@snorby.org
• snorby

Don’t be stupid, c+hange the email and the password after logging in+.

Now if you look around the site you’ll notice that Snorby isn’t getting any data just yet. So we’ll have to configure Snort!

ALT VPS Method¶

Since ALT uses a pfSense firewall, snort is installed there (at a cost to performance). And as such snort and barnyard must be configured on the pfSense firewall by going to Service -> Snort -> Edit Interface -> barnyard2

Original method¶

Now if you look around the site you’ll notice that Snorby isn’t getting any data just yet. So we’ll have to configure Snort:

dpkg-reconfigure snort-mysql

Answer the questions, set up all the interface you need for sniffing network traffic and enter Snorby’s mysql database and the username and password for it when prompted. Now that the database is configured we’ll just need to move away a lock file, so that Snort can start up.

mv /etc/snort/db-pending-config /etc/snort/db-pending-config_no_more

At this point we’re ready to launch snort:

service snort start

Let’s test it!¶

Snort should alert for nmap scans so on another box just type:

nmap -A -T5 yourhost.org

Let it run, then check Snorby. Now there’s really only one thing left before we’re done.

Make Snorby autostart rails web server on boot¶

cd /etc/init.d/
nano snorby

A simple script like this should do the trick:

#!/bin/bash

cd /var/www/snorby && bundle exec rails server -e production &

Let’s put it to start in runlevel 2:

chmod +x snorby
update-rc.d -f snorby start 2

And now Snorby will start whenever the system enters runlevel 2 and we’re done.