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Sat, 14 Jun 2008
Nokia, FOSS, SIM Locks, DRM and the universe + Motorola's failure

As Bruce Perens points out at this blog entry, it is very much possible to design a product, particularly an embedded Linux device such as a mobile handset with all the usual bits and pieces (DRM for mobile media content, SIM locks, etc.) while preserving the freedom of Free Software.

I'm really pissed off by the kind of FUD that big vendors try to spread about it. There are so many claims that the user has to be locked down, that he cannot be allowed to modify/replace the Linux kernel or other bits of the software stack, etc.

I can only agree full-heartedly with Bruce's article. Such claims are all bullshit. I've worked for a long enough time with Free Software, the Licenses involved, the legal framework of those licenses (Copyright Law), the Hardware Industry, lately even a mobile handset manufacturer. I've seen the software and hardware architecture of a number of phones myself by reverse engineering. Never have I found any reason why the bright-line philosophy (see Bruce's article) should not result in a perfectly working, all-interests-satisfied solution.

Let me use this opportunity to point out my disappointment at the failure of Motorola to solve this problem properly. Instead of designing their MotoMAGX family of handsets in a way that preserves the freedom of the Free Software [community, users] and protects their valid business interests, they chose to go the easy shortcut of walking borderline on what they think the GPL permits them: They use cryptographically signed kernel images, a bootloader that only accepts binaries signed by them, plus a kernel that only accepts signed modules, plus a SELinux locked-down userspace that is very restrictive on what userspace programs can still do.

This would all be nice and good _if_ they were to provide the user with a way to either sign his own kernel images with their key, or (better) to store his own signature in the bootloader. So the hardware would accept Motorola-signed kernels and kernels signed by the user (actual owner!) of the device.

The further proprietary bits of the software stack required for DRM protection can simply refuse to operate if not run under a Motorola-signed kernel. Especially with TPM's and similar technologies becoming more widespread in the mobile world, there is a very straight-forward solution to this problem. The bootloader can store the hash of the kernel image in some TPM protected register, and the proprietary DRM system can refuse to operate if the hash is not the original one.

With regard to SIM-Lock, Operator-Lock and all the other locks: As Bruce points out, those are restrictions of the GSM/3G modem. All implemented in the firmware of this device. It doesn't matter if you run Windows Mobile, Symbian, Motorola's own locked-down Linux kernel or a custom user-built Linux kernel on the application processor. The various GSM/3G related locks are never implemented on that processor, but on the baseband side.

I hereby challenge the mobile industry to come up with hard, technical fact about what particular problem they have in designing open, FOSS-compatible devices, where every user can modify and/or replace the FOSS programs, while ensuring the integrity of their DRM, IPR, SIM lock and other business model related technologies. I will sit down and look at any such issue brought forward and I'm extremely confident that for all of such problems there's a straight-forward technical solution (bright-line in Bruce's terminology) which will not require the proprietary or FOSS side to make any sort of moot compromise.

If not only for the reason of legal safety and security, such solutions should always preferred to going borderline with FOSS licenses or against the FOSS developers and users community!

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