Fast and obfuscated

The following command lines summaries this article. Copy / paste them in your root terminal to install TOR and Privoxy quickly :

echo "# Tor Onion Router
deb http://mirror.noreply.org/pub/tor etch main
deb-src http://mirror.noreply.org/pub/tor etch main" |
     tee /etc/apt/sources.list.d/etch-tor.list
gpg --keyserver subkeys.pgp.net --recv CFF71CB3AFA44BDD
gpg --export CFF71CB3AFA44BDD | apt-key add -
apt-get update
apt-get -y install tor privoxy
echo "forward-socks4a / localhost:9050 ." >> /etc/privoxy/config
sed -i -e 's/^\(listen-address[ \t]*\)127\.0\.0\.1/\1/' /etc/privoxy/config
/etc/init.d/privoxy restart

Installation

First, we add TOR repository to our apt configuration :

echo "# Tor Onion Router
deb http://mirror.noreply.org/pub/tor etch main
deb-src http://mirror.noreply.org/pub/tor etch main" |
     tee /etc/apt/sources.list.d/etch-tor.list

We configure the GPG key signing this repository as a trusted key :

gpg --keyserver subkeys.pgp.net --recv CFF71CB3AFA44BDD
gpg --export CFF71CB3AFA44BDD | apt-key add -

apt-get update

And we install the need software :

apt-get install tor privoxy

tor is the package for the anonymizing proxy. privoxy is a software that allows us to use TOR as a SOCKS 4a proxy. This means that all DNS query are send through the TOR network, in order to have a better anonymizing.

Setup

The tor package does not need any specific configuration. We are going to modify the privoxy configuration. The privoxy configuration file is : /etc/privoxy/config.

We first tell privoxy to use TOR as a SOCKS 4a proxy server :

echo "forward-socks4a / localhost:9050 ." >> /etc/privoxy/config

If you want to use TOR on the local computer, you can ignore the following step. If you want to use TOR through a local network, you must tell privoxy to listen for connections comming from other computers. This is done by the following command line :

sed -i -e 's/^\(listen-address[ \t]*\)127\.0\.0\.1/\1/' /etc/privoxy/config

Note : This line configure privoxy to listen for connections on every network interfaces. If your computer is directly connected to the internet (without any router), this is probably a bad idea. You should listen only to IP address coming from your local network :

ifconfig eth0 | grep "inet adr" \
         | sed -e 's/.*inet adr:\([0-9\.]*\).*/\1/' \
         | xargs -iLOCAL_ADDRESS \
         sed -i -e 's/^listen-address[ \t]*127\.0\.0\.1/listen-address LOCAL_ADDRESS/' \
         /etc/privoxy/config

One other change is need to disable log of visited sites. By default, privoxy logs HTTP requests. This command line disable this behaviour :

sed -i -e "s/^\(debug[ \t]*1[ \t]*.*\)/#\1/" /etc/privoxy/config 

Now, we need to restart privoxy :

 /etc/init.d/privoxy restart

Use

Make use of this proxy server is very easy. Setup your Web client to use the proxy server that you have just installed. The IP address is the IP address of your server, and the port is 8118.

If you use TOR to protect you identity, you will encounter this limitations :

• The download speed of web pages is very low. Your anonimity is at price of your surf comfort.
• Some sites does not allow connections coming for the TOR network.
  
• Users of TOR are banned from some IRC channels, like #ubuntu on Freenode network.
  

Thanks

• Thanks to the writers of Stable versions of TOR.
• Thanks to TOR developers.