2008-12-17

Accessing a Truecrypt encrypted external drive that uses the ext3 filesystem from Mac OS X

As covered in another post, I have a laptop home file server set up that stores its files on two external drives that are encrypted using Truecrypt and which use the ext3 filesystem. One of my goals of that project was to be able to grab one of the external drives and be able to read it from another computer (i.e. so I am not hosed if the laptop dies).

I was pretty confident that I could meet my goal by just firing up an old laptop that has Xubuntu installed, so I didn't even test that. However, I wanted to be able to read my encrypted external drives using my new Macbook.

After lots of googling I couldn't find any program that would allow mounting an ext3 filesystem directly on Mac OS X. Maybe its out there, but I couldn't find it. So, it was on to plan B, which was to install a VMware Fusion Xubuntu virtual machine on my Macbook and use that.

I fired up VMware Fusion and went to File > New and then followed the wizard for setting up a new virtual machine. I already had the ISO file for Xubuntu 8.04 desktop, so I told it to use that instead of a CD. I went with the quick install option (I think that was the name) and everything went very smoothly with setting up the virtual machine.

After I got to the Xubuntu desktop I did a system update to bring it up to date, then I downloaded the Truecrypt installer for Ubuntu from the Truecrypt website, unarchived it, and then ran the installer script which worked without any hitches.

Then I logged onto my home file server using SSH and dismounted one of the encrypted drives using truecrypt -d /media/truecrypt2, then disconnected its USB cable, then its power, moved it over to my Macbook, plugged it into power, and then plugged in the USB cable. At that point Mac OS X gave me a dialog about not being able to mount the drive and I clicked the ignore button. Then I went to the Xubuntu virtual machine window and clicked the little USB icon on the bottom to connect the external drive to the virtual machine.

Then I fired up a terminal in the Xubuntu virtual machine and checked /dev for the external drive by running ls sd*. I saw there was an sdb and sdb1, and I guessed that that was the external drive, so I then ran truecrypt /dev/sdb1 /media/truecrypt1 to mount it and entered the password for the drive at the prompt

I then went to the Xubuntu file manager and navigated to /media/truecrypt1 and verified that I could open files on the external drive.