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Contact/Impressum

       
Fri, 16 Jul 2010
Motorola locking down the DroidX and Droid2 in a nasty way

There are plenty of reports in recent days about the level of locking-down that Motorola is apparently doing on their most recent Android products, the Droid 2 and the Droid X.

This goes as far as to an (I believe unconfirmed) slashdot.org report claiming that not only there is the more or less typical DRM on software (i.e. cryptographic signature validation chain), but there also is an eFuse that that is blown if something happens wrong during the booting process.

To the best of my knowledge (and I'm doing mobile phone reverse engineering for about 6 years now), this is the first time I hear of something like this. If true, it sounds pretty dangerous to me. What if something goes wrong during an update (such as a power failure during software update)? What if you really have a non-correctable multi-bit error in your NAND Flash? In that case, cryptographic verification of the firmware fails and the eFuse would be blown, resulting in your device being a brick. This could eventually backfire massively to Motorola.

The best comment from the slashdot.org thread:
You can legally buy a gun that only shoots in the direction of the person pulling the trigger, but it doesn't mean it's a good idea.

Reading something like this almost makes me very depressed. Motorola is benefitting from the billions-of-dollar-worth development of existing Free Software projects like the Linux kernel, but they now want to take away the fundamental right to run modified versions of that very software. Somebody needs to slap them with a very large trout.

I'm not really surprised that they are doing it, though. Motorola has shown that direction even years ago when they first used SELinux as part of their later pre-Android Linux phones (EZX and MAGX). They didn't use it to enhance the security of the user, but to enhance the security _from_ the user.

Please also note this great post by Bradley M. Kuhn on the subject matter. If you don't know Bradley, he's been doing GPL enforcement for the last 12 years - for the Free Software Foundation and the Software Freedom Law Center. In his post, he actually thanks Motorola to publicly state that they actually want to lock their phones down (as opposed to Apple).

What's even more interesting though is his elaboration on the scripts to control compilation and installation clause of GPLv2. This is indeed something that most people tend to overlook when it comes to GPL[v2] compliance and we see this a lot during our gpl-violations.org work.

And in fact, for a very long time, I have been teaching and educating this fact during my GPL related talks and trainings: In software specific for embedded devices, the scripts to control installation are incomplete, if you do not provide a means to install the software onto the actual device. Where else would you be reasonably install the Linux kernel image that is made specifically to work on such a particular mobile phone model? Due to the custom nature of Linux kernels for embedded targets, it wouldn't even run anywhere else.

I've never taken any such issue to court so far - but it was a frequent dispute in out-of-court GPL enforcement we've been doing at gpl-violations.org. I'm definitely curious to see what will be the first court case addressing that issue. The ever power-hungry manufacturers of mobile phones seem like they deserve it.

UPDATE:
Apparently Motorola has released some statement that denies they use eFuses to brick the device. All it does is to render the device unable to boot until some Motorola-certified/signed/authorized software is loaded on the device again. They did not specify how that could be done, though. Still, even without the eFuse bricking, I find it outrageous that the Industry (including Motorola) expect their customers pay hundreds of dollars for a device that is then still owned by Motorola rather than that very customer. It's like selling something but still retaining ownership of it. Doesn't that make you feel strange, too?

[ /linux/mobile | permanent link ]