Recipe 13.5. Creating a Persistent, Encrypted Knoppix Home Directory

13.5.1 Problem

You really like running Knoppix from the CD, because it cannot be infested by viruses, Trojans, or rootkits, and you would like to use it in place of a hard drive installation. But there's a problem: where do you store personal data, email, and other things that you'd like to keep with you? You want a secure home directory in which to store email and other data files.

13.5.2 Solution

Run Knoppix Configure Create to make a persistent Knoppix home directory. You'll have the option of creating /home on the hard drive, or on removeable media such as USB memory sticks, compact flash cards, or Zip disks. This creates a file called knoppix.img.

Say yes when it asks you if you want to create an AES-encrypted directory. The directory will be encrypted with a 256-bit key. You have to come up with a passphrase of at least 20 characters. Make it a sentence that you can remember, like "thisismylongpassword," because you'll need it every time you boot.

To boot using your nice, new encrypted /home, insert your removable media and type:

boot: knoppix home=/dev/sda1

If you also saved your Knoppix configuration, you can specify both:

boot: knoppix home=/dev/sda1  myconfig=/dev/sda1

Your new /home directory will appear in Knoppix as /home/knoppix and will be automatically mounted at boot. If you store your encrypted /home in an existing Linux partition on the hard drive, the whole partition will be mounted.

13.5.3 Discussion

The default size of /home/knoppix is 30 MB. Make it as large as you need.

13.5.4 See Also

• Documentation on the Knoppix CD

• Knoppix.net (http://www.knoppix.net/)

• Klaus Knopper's official homepage (http://www.knopper.net/)