I’ve written about Apple’s use of the TPM chip before. My basic conclusion was, there’s no evidence Apple is using the chip for anything sinister, or at all in current versions (Tiger). However, I also said Apple should use the chip as a basis for secure vitualization in Leopard:
…Apple should write a fully trusted hypervisor into the EFI (using the TPM) and run everything inside virtual machines, including Mac OS X for Intel itself. Booting some version of Windows into a second VM would be easy, then, and there wouldn’t be a full version of Mac OS X for Intel for people to run on standard PCs either. I don’t think dual-booting is a good solution, I believe Apple was just testing the waters with BootCamp.
I still think virtualization is a good idea… however, there’s new evidence that Apple doesn’t think so, or at least not in conjunction with the TPM chip.
First, ifixit posted a disassembly of the new Core 2 Duo MacBook Pros, with zoomed-in photos of the logic board. They’re not detailed enough to show all IC part numbers, but I can say with some confidence that there’s no TPM chip at all. However, to the right of the RAM socket in the second picture, there’s an empty space for a 28-pin flat-pack IC – just the size of the Infineon SLB9635TT chip found on all previous Intel Macs. I’ve been searching for a similarly detailed picture of the Mac Pro’s motherboard, with no luck so far.
Second, Amit Singh of Mac OS X Internals fame – which I bought and read recently, BTW – has posted, in his usual precise style, details on how to use those Macs’ TPM chip. Here are some salient points:
The media has been discussing “Apple’s use of TPM” for a long time now. There have been numerous reports of system attackers bypassing “Apple’s TPM protection” and finding “Apple’s TPM keys.” Nevertheless, it is important to note that Apple does not use the TPM. If you have a TPM-equipped Macintosh computer, you can use the TPM for its intended purpose, with no side effect on the normal working of Mac OS X.
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At the time of this writing (October 2006), the newest Apple computer models, such as the MacPro and the revised MacBook Pro do not contain an onboard TPM. Theoretically, Apple could bring the TPM back, perhaps, if there were enough interest (after all, it is increasingly common to find TPMs in current notebook computers), but that’s another story.
He then goes on with very detailed instructions on how to write, install and use a device driver for the TPM chip.
All this is very interesting, but as the TPM isn’t anymore standard equipment you could rely on finding on any Intel Mac, this is more an academic exercise. I doubt that Apple will implement anything important in Leopard that won’t run on the new Pro machines, so no trusted hypervisor for me. Ah well…
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