Monthly Archives: October 2006

Disk encryption in Linux (II): Easy encryption with EncFS

Sometimes you don’t want to encrypt all of your files. You just have some important data you’d like to keep protected, but your other files are not confidential at all and you don’t care if someone steals your Firefox bookmarks or your .procmailrc.

In those cases encrypting a whole disk or even a single partition might be too complicated (you don’t want to mess with partitions), or it could make your system too slow. There are other alternatives. A classical approach is to encrypt your important files using a tool like GnuPG. While this method works perfectly, it’s not the most convenient approach when you have, say, dozens of different files to encrypt.

EncFS is a cryptographic filesystem that transparently encrypts a whole directory tree. Data is always kept encrypted in a regular directory within an existing filesystem, and you have to mount that directory using EncFS in order to see its contents. Thus, once mounted, encrypted files can be accessed through this virtual filesystem just like any other file: you can edit, copy, rename and erase them just like you would do with any other file.

One of the main problems of EncFS is that each file stored maps to an encrypted file, so even though the file names and contents remain protected, anyone with access to your hard disk can see how many files you have, the directory structure, the metadata and even the approximate size of each file. If that’s not a problem for your needs, EncFS is a good piece of software and it’s very easy to install, set up and use.

Disk encryption in Linux (I): Introduction

This post is the first in a series dedicated to disk encryption in Linux-based operating systems, namely Debian GNU/Linux 3.1 (sarge), but all these tips should be useful for other systems too.

As portable mass storage devices (such as USB flash drives, external hard disks or even laptops) are becoming more and more popular there’s a growing need to keep all this data secure in case a device is stolen (of course to keep your files secure you should also back up them, but that’s a different subject I will not cover here).

Disk encryption is a complex issue: there are plenty of encryption algorithms and disk format standards. New systems appear each year and old ones become deprecated. All these systems vary in speed, complexity, security and even stability. To put things worse, most disk encryption systems are not compatible to each other and are usually limited to one specific operating system.

There’s a wikipedia article about disk encryption software that can serve as a quick overview of some of the most popular systems available.

In this series of posts I’ll write about some of the most basic forms of encryption to cover the usual needs. I’d like to note that I’m not writing about user programs that encrypt files manually, such as GnuPG or some ZIP compressors. I’ll just cover methods that encrypt filesystems on the fly, that is, once set up you don’t need to care when you change your data: it will be encrypted automatically as you write it to disk.

I hope you’ll find these articles useful. Comments and criticism are welcome.

The Last.fm player and radio stations

As some of you might already know, Last.fm is an online community based on musical tastes. You have to create an account (it’s free), install a plugin on your music player and your program will send statistics of the music you play in your computer to Last.fm.

Then you will be able to see what is the music you listen to the most, view recommendations, users with musical tastes similar to yours (called neighbours), create communities, blog, and many other things.

Besides this, Last.fm also offers personalized online radio. Using a free player downloadable from its website you can listen to many radio stations, including things like:

  • Music your neighbours listen to.
  • Music similar to a given artist/band.
  • Music recommended to you by Last.fm
  • Music tagged with a given tag.

The streaming quality is good (MP3 at 128kbps) and you can skip any track, and tell the player which songs you love the most and which songs you don’t want to hear anymore.

The player is very small and nice, and it is released under the GNU GPL license (you can access the Subversion repository too), so congratulations to the Last.fm people.

Besides the official player, a number of other compatible third-party players are out, such as Last Exit (GTK+) and Shell.FM (console). Recent versions of Amarok can also play Last.fm radios.

The official Last.fm player is available in Debian etch (testing). If you want to install it in a Debian sarge, you can use a backport. Just add 'deb http://www.backports.org/debian/ sarge-backports main' to your sources.list and run 'apt-get -t sarge-backports install lastfm'.