On 24.04.2008 20:32, C. Scott Ananian wrote: > 11. Bitfrost: initial activation security. > > Our deployment countries are very concerned with theft of XOs. This > item and the next address different mechanisms OLPC has designed to > mitigate and manage this risk. > > "Initial activation security" means that an XO as delivered from the > factory is a worthless brick. It cannot be transformed into a > functional machine without the use of an activation key, tied to the > machine's serial number, which is generated by OLPC or the deployment > country. The goal of this feature is to deter theft-in-transit: > activation keys and the XO hardware follow different paths to the > target school, minimizing the value of the XO until it arrives in the > hands of its child owner. > > Initial activation security is likely to be reasonably implementable > on Sugar/Windows. Mitch Bradley has been working on making Windows > boot under OpenFirmware, and most of initial activation security is > implemented in OpenFirmware's secure boot path. The initial > activation step currently involves booting a Linux kernel with a > special ramdisk which validates activation leases and writes them to > internal flash; this process could be used with only minor > modifications to perform activation of Sugar/Windows machines. > > > 12. Bitfrost: active and passive kill. > > Some countries want more aggressive anti-theft protection. The terms > of the GPL (as well as our own moral compasses) require us to allow > the user to disable these mechanisms, but schoolkids who wish to keep > them enabled gain some additional anti-theft protection. > > The theft-deterrence comes in two forms. The first, passive kill, > limits the lifetime of the initial activation lease (item #11). The > activation lease must be renewed periodically, or the machine reverts > to the unactivated state. A thief is guaranteed that a stolen machine > will not be usable long. > > The vulnerability in this scheme is the real-time clock. The XO > hardware does not contain an hardware-protected clock (although we may > be able to leverage firmware in the embedded controller to provide > this), and so the burden of protecting the passive kill system from > clock-reset attacks falls on the operating system. It is rather > difficult to secure Sugar/GNU/Linux against these attacks; it is > unlikely that Sugar/Windows will ever be adequately secure. (If we > move to an EC-based implementation, then Sugar/Windows will require > Windows kernel expertise in order to follow suit.) > > Active kill piggybacks on the update management system: when the XO > performs a network transaction to look for an update, it may also be > informed that it has been stolen, and immediately enter the > deactivated state. The obvious vulnerability is in the networking: an > enterprising thief may conspire to prevent the XO from ever connecting > to the theft-deterrence server. A secondary vulnerability is in the > daemon which periodically checks the theft-deterrence server: > again, the burden falls on the operating system to protect that > process from interference. Again, this is difficult enough on > Sugar/GNU/Linux; it is much more so on Sugar/Windows XP. > > For completeness, I will note that although passive and active kill > theft-deterrence systems have been implemented on Sugar/GNU/Linux, > only initial activation security has been deployed in the field. > Passive and active kill systems entail large support costs which OLPC > has chosen to date not to incur. >
AFAIK the hardware side of P_THEFT alias theft protection alias activation security/kill functionality has not been implemented, rendering all software efforts moot. Unless the manufacturing details have changed since my last inquiry, I can unlock ~4 XO machines per hour WITHOUT having a developer key. The only thing I need are some really affordable tools. If someone else disassembles the machines for me, I think unlocking 10 machines per hour is well within the doable range. For the record: I will not take orders for mass-unlocking unless ownership is proven. Regards, Carl-Daniel _______________________________________________ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel