Thoughts on SSDs and encryption

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My laptop is just over 3 years old, which is about the point I start to think about a replacement. At present there's nothing that's an obvious contender so I've been looking at an SSD to prolong it by another year or two.

One of the other thoughts I had is that I currently use dm-crypt under Linux to provide whole disk encryption for everything except the boot partition - I have a bunch of my personal financial and immigration documents stored that I'd prefer not to get disclosed if my laptop is stolen. Modern drives have started offered integral AES encryption options, so perhaps I could offload that to the drive (my i5 470UM lacks the hardware instructions for this).

General consensus in the pub (where all the best security advice is to be found) is that no one present trusted SSD firmware authors to not use some badly chosen AES crypto mode, or leave the key lying around plain text in easily readable flash, or some other implementation mishap.

So how hard would it be to retrofit reliable (or at least source verifiable and thus more reliable) crypto to an SSD? There was an impressive article recently about reverse engineering the firmware of a HDD, to the point of modifying data returned to the host and also running Linux on the controller. It seems that SSD firmware should be easier - NAND is simpler to talk to than motors and magnetic sensors, right? It's a case of gluing together a SATA interface, a NAND controller and an AES offload engine, yes?

Aside from the minor matter of finding a suitable drive with an available JTAG interface, a controller with docs (or more likely that can be reverse engineered) and enough time to produce a replacement open firmware, that is.

Alternatively can anyone provide some idea of how secure the available laptop SSDs on the market actually are? I'm fine with "the NSA can read your data if they want" because a determined attacker will be able to find other ways to get my data anyway, but I don't want "anyone who finds the drive can use this loophole in the firmware by wiggling some bits with jtag to dump the key and read all your data".

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This page contains a single entry by Jonathan McDowell published on December 3, 2013 9:17 PM.

Building a new house server was the previous entry in this blog.

Fixing my parents' ADSL is the next entry in this blog.

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