Filtering Web banner ads from Linux
- — 05 July, 2002 07:45
In conjunction with this month's Web and You feature on blocking Web ads, we look at some methods of bypassing these annoyances in a Linux world. Web advertisements can be removed using software that acts as a filter. This software is known as a proxy server. Once set up, any Web browser that supports proxies can use the filter seamlessly to access the Web, advertisement free.
Internet Junkbuster, included on this month's cover CD, is the easiest-to-install advertisement filter for Linux currently available. It is quite good at filtering common types of advertisements and, additionally, it can also filter cookies and other information that is sometimes used to track you as you browse the Internet.
Installation
The proxy server should be installed on the computer you use to "access the Internet. For most people, this will be your Linux computer, but if you are running an Internet gateway/firewall, you should install Internet Junkbuster on this machine instead.
To install Internet Junkbuster, first decompress it by typing in a shell:
$ tar -xvfZ ijb20.tar.Z
Change to the directory created. There is no need to con-"figure Internet Junkbuster for Linux, so to compile it simply type:
$ make
Now that Internet Junkbuster has been compiled, it can be installed by typing as root:
$ cp junkbuster /usr/local/bin
The next step in installing Internet Junkbuster is configuring the filtering rules. A sample configuration file (junkbstr.ini) has been included in the Junkbuster directory. If you are interested in maximising Internet Junkbuster's complete functionality, read this file and use it as a blueprint for your own configuration file. Alternatively, create a file as root in /etc using your text editor with the following contents:
blockfile /etc/blockfile.ini
The blockfile is a listing of Web addresses that the Internet Junkbuster proxy will filter from your Web browser. Next you need to create the file /etc/blockfile.ini. We have included a sample blockfile.ini in the junkbuster directory on this month's cover CD. It is intended as a sample for you to build your own blockfile from, but it works quite effectively at blocking advertisements from most Web sites. Copy the sample blockfile.ini from the cover CD to /etc as root.
You can now test Internet Junkbuster by typing:
$ junkbuster /etc/junkbstr.ini &
To use the filter with your Web browser, edit your browser's configuration options and set the http proxy server to "127.0.0.1" (or the IP of the server on which you installed Internet Junkbuster) with a port of "8000". Most browsers keep this configuration under 'Advanced' (FIGURE 1).
After following these steps, you should now be able to view the Internet advertisement free. The space where ads once ran will now display an empty image, ensuring that your favourite Web site's layout isn't broken.
The final step for installing Junkbuster is to include it as an application that starts when you boot your computer. Depending on your Linux distribution, this file will either need to be created in /etc/init.d or /etc/rc.d/init.d. You may need to modify this file for your system. My Junkbuster initialisation file is as follows:
#!/bin/sh
case "$1" in
start)
echo -n "Starting Internet Junkbuster"
/usr/local/bin/junkbuster /etc/junkbstr.ini &
;
Br> ; stop)
echo -n "Stopping Internet Junkbuster"
killall junkbuster
;;
restart|force-reload)
sh $0 stop
sh $0 start
;;
*)
echo "Usage: /etc/init.d/internetjunkbuster
{start|stop|restart|force-reload}"
exit 1
;;
esac
exit 0
Once this file has been created, save it to the correct path and name the file "internetjunkbuster". The file needs to be made executable by typing:
$ chmod +x /etc/init.d/internetjunkbuster
On reboot, Internet Junkbuster should start automatically. You can stop it by typing /etc/init.d/internetjunkbuster stop.
