Windows users have more security options, and that’s just the way it is. Or is it?
Let’s start with the obvious: I love BitLocker and I cannot lie. Despite its faults, it remains a great example of a real-world security feature that delivers immediate value. It’s fully supported by the OS manufacturer, meets government security standards, and doesn’t have to rely on skanky hacks to work its magic.
Windows laptop users can also take advantage of Seagate’s Momentus FDE line of disk drives. These disks, sometimes called self-encrypting disks or just SEDs, perform hardware encryption, and they are qualified by the US National Security Agency as meeting NSTISSP #11. Unfortunately, these drives require support in the BIOS. Since Apple’s laptops all use EFI instead of the standard x86/x64 BIOS, you can’t just plop a Momentus FDE into your Mac and expect it to work.
The only solution I’ve found to get an SED to work in a modern Mac laptop is from WinMagic. Their SecureDoc product is essentially a full-volume encryption tool that competes directly with BitLocker, as well as with other FVE products from PGP, PointSec, and so on. The big difference: the Mac version of SecureDoc supports Momentus FDE disks. Naturally I had to try it.
Installation is simple: you run an installer, which adds a couple of kernel drivers and modifies the boot loader. If (and only if) it detects an unlocked Momentus FDE as the boot volume, it will ask whether you want to use hardware or software encryption. (The installer also tells you that it will change the system’s hibernation mode, but let’s not get ahead of ourselves yet…)
When you’re done, you must reboot, at which point you see the new (and quite ugly) SecureDoc login screen. When you log in here, the SecureDoc bootloader unlocks the FDE disk and the normal Mac OS X boot cycle proceeds.
The docs ask that you turn off pagefile encryption by unchecking the "Use secure virtual memory" option in the General pane of the Security preferences tool. This makes sense: there’s no reason to ask the OS to encrypt the page file if the disk on which it lives is already encrypted. You must also turn off the "Put hard drive to sleep whenever possible" checkbox, as the OS doesn’t deal well with having the disk go to sleep (and thus get locked) while you’re using it.
In my test install, I ran into an odd problem: the machine would freeze when waking from sleep. The cursor and keyboard would work normally, but I’d get the spinning rainbow pizza of death. After doing some digging, and with the help of WinMagic’s tech support folks, I determined that the system’s hibernation mode wasn’t properly set by the installer. (Page 4 of this document is the only place I’ve found the different hibernation mode codes explained.) Uninstalling the SecureDoc software, manually setting the hibernation mode with the pmset tool, and reinstalling it fixed the problem and it has worked flawlessly since.
The standalone version of SecureDoc doesn’t have the same set of management or control features that BitLocker does. Of course, that’s because WinMagic wants you to buy their server-based toolset, which uses a group policy-like mechanism to enforce whatever encryption policies you choose. Without having tested either the server tool or the Windows version, I’m not ready to pick a winner between BitLocker and SecureDoc, but for the Mac it’s a low-impact solution that does what it says, and I’m happy with it so far.