Data encryption and Ubuntu, Part III

By Hamish Taylor
Sunday, 30 November 2008 02:30

Opinion and Analysis

In a continuing series of articles highlighting that GNU/Linux is a viable replacement operating system, today we're exploring how to encrypt emails using the popular Ubuntu distribution.

In the previous article we looked at the basics of using PGP, creating and backing up PGP keys and using them to encrypt files locally. Now we'll look at how to send someone an encrypted email.

The simplest method to send someone an encrypted email is to get their Public Key and import that into your system. Then write a text file or document, encrypt it and attach the encrypted file to an ordinary email to them. You're effectively just sending them an encrypted attachment.

Whilst this will work well, the subject line and anything that you type into the body of the message will remain unencrypted; only the attachment will be encrypted.

The recipient has to download the attachment to their computer, decrypt it, open it and then read it.

I'm not sure about you but this all sounds a bit like too much like hard work to me!

What you can do is use your email application to do all the hard work for you.

Whilst Firefox has the FireGPG extension which gives this functionality to GMail users (not sure about other webmail based email users), I have found it a bit clunky to use.

Thunderbird has the Enigmail extension which gives it seamless encryption/decryption functionality.

Evolution (the default email client in Ubuntu) has built-in encryption/decryption and I'll be using that as the basis of the following instructions. However, the basic ideas are pretty much the same across all email clients.

As far as I have been able to determine, all of these applications link to the PGP "Key Chain" that you have on your computer via the Passwords and Encryption Keys menu (found under Applications, Accessories). Each email client does not maintain it's own key chains.

Please read onto page 2 to see how to make Evolution "see" your PGP key...