Tor is a proxy server which allows its users to hide their IP address from the websites they connect to. In order to provide this level of anonymity however, it introduces latency into these connections, an unfortunate performance-privacy trade-off which means that few users choose to do all of their browsing through Tor.

Here are a few things that I have found work quite well through Tor. If there are any other interesting use cases I've missed (e.g. reviewing academic papers), please leave a comment!

Tor setup

There are already great docs on how to install and configure the Tor server and the only thing I would add is that I've found that having a Polipo proxy around is quite useful for those applications that support HTTP proxies but not SOCKS proxies.

On Debian, it's just a matter of installing the polipo package and then setting the following in /etc/polipo/config:

logSyslog = true
logFile = /var/log/polipo/polipo.log

# Configure polipo for use with tor
proxyAddress = ""
proxyPort = 8008
allowedClients =
allowedPorts = 1-65535
proxyName = "localhost"
cacheIsShared = false
socksParentProxy = "localhost:9050"
socksProxyType = socks5
chunkHighMark = 67108864
diskCacheRoot = ""
localDocumentRoot = ""
disableLocalInterface = true
disableConfiguration = true
dnsQueryIPv6 = no
dnsUseGethostbyname = yes
disableVia = true
censoredHeaders = from,accept-language,x-pad,link
censorReferer = maybe

# Suggestions from Incognito configuration
maxConnectionAge = 5m
maxConnectionRequests = 120
serverMaxSlots = 8
serverSlots = 2
tunnelAllowedPorts = 1-65535

RSS feeds

The whole idea behind RSS feeds is that articles are downloaded in batch ahead of time. In other words, latency doesn't matter.

I use akregator to read blogs and the way to make it fetch articles over Tor is to change the KDE-wide proxy server using systemsettings and setting a manual proxy of localhost on port 8008 (i.e. the local instance of Polipo). If you don't see the proxy settings in the KDE control panel, make sure that the kde-baseapps-bin, libkonq-common and kpart-webkit packages are installed.

Similarly, I use podget to automatically fetch podcasts through this cron job in /etc/cron.d/podget-francois:

0 12 * * 1-5 francois   http_proxy=http://localhost:8008/ https_proxy=http://localhost:8008/ nice ionice -n7 /usr/bin/podget -s

Prior to that, I was using hpodder and had the following in ~/.hpodder/curlrc:



For those of us using the GNU Privacy Guard to exchange encrypted emails, keeping our public keyring up to date is important since it's the only way to ensure that revoked keys are taken into account. The script I use for this runs once a day and has the unfortunate side effect of revealing the contents of my address book to the keyserver I use.

Therefore, I figured that I should at least hide my IP address by putting the following in ~/.gnupg/gpg.conf:

keyserver-options http-proxy=

However, that tends to makes key submission fail and so I created a key submission alias in my ~/.bashrc which avoids sending keys through Tor:

alias gpgsendkeys='gpg --send-keys --keyserver-options http-proxy=""'

Package updates

Since most Debian packages are fairly small, downloading them over Tor doesn't take a whole lot longer. Large updates on the other hand are affected unless you do them in the background like I do with this daily cron job:

apt-get -qq update
apt-get -qq clean
apt-get --download-only --assume-yes --force-yes -qq dist-upgrade
apt-get -qq autoclean

To do updates over Tor, simply install the apt-transport-tor package and then replace http:// with tor+http:// everywhere in your /etc/apt/sources.list so that it looks like:

deb tor+ sid main contrib
deb-src tor+ sid main contrib
deb tor+ experimental main
deb-src tor+ experimental main

Instant messaging

Communication via XMPP is another use case that's not affected much by a bit of extra latency.

To get Pidgin to talk to an XMPP server over Tor, simply open "Tools | Preferences" and set a Tor/Privacy (SOCKS5) proxy of on port 9050.


Finally, I found that since I am running GMail in a separate browser profile, I can take advantage of GMail's excellent caching and preloading and run the whole thing over Tor by setting that entire browser profile to run its traffic through the Tor SOCKS proxy on port 9050.