Successful test of encrypted usb drive

[Bruno Wolff III]

While I think this feature has been available for a while, it might be worth
mentioning with the encrypted install feature.
I tried it out as follows (as root):
   Plug in the usb drive and not the device name (/dev/sdc1 in my case)
   Erase it with random data (which can take a while and isn't really needed
   if no senstive data was previously on the device and you don't care about
   leaking which blocks on the drive have been written)
dd if=/dev/urandom of=/dev/sdc1
   Create the encrypted area
cryptsetup luksFormat /dev/sdc1
   Enter the passphrase twice
   Make the encrypted area a usable device
   The name at the end is arbitrary, but don't use one already in use
cryptsetup luksOpen /dev/sdc1 luks-usb
   Create the file system using the name from above as the device
mkfs -t ext3 /dev/mapper/luks-usb
   Close the encrypted device
cryptsetup luksClose /dev/mapper/luks-usb
   Unplug the device

Now when you plug in the device (while logged in at the console using a GUI)
you will get asked for the passphrase and after prodiving the correct one
the device will work like a normal removable device.

Note that doing this limits you to using it with systems that support luks
and ext3, which isn't going to work for everyone.