BFD Installation And Configuration

By | August 24, 2009

BFD Configuration And Installation

BFD (Brute Force Detection)
BFD is a modular shell script for parsing applicable logs and checking for authentication failures. There is not much complexity or detail to BFD yet and likewise it is very straight-forward in its installation, configuration and usage. The reason behind BFD is very simple; the fact there is little to no authentication and brute force auditing programs in the linux community that work in conjunction with a firewall or real-time facility to place bans. BFD is available at: http://www.rfxnetworks.com/bfd.php

Bfd works with apf. With the help of apf, bfd deny the attackers ip. The denied ip is listed on

#cat /etc/apf/deny_hosts.rules

The file have  comment shown regarding which type of attack does the system undergone . To make the ip allow we need to remove the ip address from the apf deny hosts rule and reload the apf using the command ”apf -r”

#apf  -d  <ip> to deny ip address.

#apf  -a <ip> to add the ip to allow list.

If the ip is added on deny list remove it from the file and then add it to allow list.

This guide will show you how to install and configure BFD to protect your system from brute force hack attempts.

#cat /etc/apf/allow_hosts.rules

file shows the allowed ip address.

Requirements:
– You MUST have APF Firewall Installed before installing BFD – it works with APF and requires some APF files to operate.
– Root SSH access to your server

Updated: April 13, 2005

Lets begin!
Login to your server through SSH and su to the root user.

1. cd /root/downloads or another temporary folder where you store your files.

2. wget http://www.rfxnetworks.com/downloads/bfd-current.tar.gz

3. tar -xvzf bfd-current.tar.gz

4. cd bfd-0.7

5. Run the install file: ./install.sh
You will receive a message saying it has been installed

.: BFD installed
Install path:    /usr/local/bfd
Config path:     /usr/local/bfd/conf.bfd
Executable path: /usr/local/sbin/bfd

6. Lets edit the configuration file: pico /usr/local/bfd/conf.bfd

7. Enable brute force hack attempt alerts:
Find:
ALERT_USR=”0″ CHANGE TO: ALERT_USR=”1″

Find: EMAIL_USR=”root” CHANGE TO: EMAIL_USR=”your@yourdomain.com”

Save the changes: Ctrl+X then Y

8. Prevent locking yourself out!
pico -w /usr/local/bfd/ignore.hosts and add your own trusted IPs
Eg:
192.168.1.1

Save the changes: Ctrl+X then Y

BFD uses APF’ cli insert feature
and as such will override any allow_hosts.rules entries users have in-place.
So be sure to add your trusted ip addresses to the ignore file to prevent
locking yourself out.

9. Run the program!
/usr/local/sbin/bfd -s

10. Customize your applicatoins brute force configuration
Check out the
rules directory in your /usr/local/bfd

Here you’ll find all kinds of pre-made rules for popular services such as Apache, and ProFTPD w00t!
If you have any clue about shell scripting you can customize them or create new rules for enhanced brute force detection and prevent attacks.

Thanks to RFX Networks for creating another great script for the community, Brute Force Detection is excellent!

Melbin Mathew

I am Melbin Mathew, Systems Engineer from Kerala, India. I live with my parents, daughter and my wonderful wife. I graduated in 2004 with a bachelor’s degree in Electronics and Hardware from Mahatma Gandhi University, Kottayam and completed certification in MCITP, RHCE, CCNA, VCP ...Read More
Category: Linux

About Melbin Mathew

I am Melbin Mathew, Systems Engineer from Kerala, India. I live with my parents, daughter and my wonderful wife. I graduated in 2004 with a bachelor’s degree in Electronics and Hardware from Mahatma Gandhi University, Kottayam and completed certification in MCITP, RHCE, CCNA, VCP ...Read More