Re: A _good_ and valid use for TPM

[Michal Suchanek]

2009/2/23 step21 <address@hidden>:
> This whole debate made read up a little bit on TPM, for example I
> checked http://www.osxbook.com/book/bonus/chapter10/tpm/
> (osx book is a very nice resource for mac/os x system internals)
> regarding tpms on apple hardware.
> Now contrary to what some outdated resources/rumours say, at least all
> newer intel mac don't include any tpm at all, the only thing that
> definitely did contain one were the developer boxes that were shipped
> to apple developer connection subscribers when the transition from ppc
> to intel started. Also, I can confirm this for my macbook air, neither
> the device tree inside os x or logic board photos from ifixit give any
> indication of a tpm chip, also all sources that don't rely on rumours
> confirm that apart from developer boxes intel macs don't contain one.
> You might say, now, how is that important? Well, I don't know about
> current i386/bios boards, for once because there are so many and
> because I don't intend to buy one in the near future, but how
> widespread is the use of tpm chips nowadays, especially considering
> the thing hardly counts as a new development any more? I think this is
> important to include in those ideologic discussions, especially cause
> if  there is one company that I think would try to lock their hardware
> down as much as possible using something like a tpm, it's apple, but
> they don't. Also, all the annoying things like drm or this copy
> protection thing for displays (don't know what it's called atm, where
> all possible without a tpm.
> So, how widespread are builtin tpms for normal pc boards?
> As for osx86, they have a really old wiki page about tpm, but a
> current comment I found said more or less to patch a current version
> of os x to run on normal hardware you just have to "patch out efi with
> 1-2 nops and hardocde the fsb with another 1-2 nops"
> http://www.insanelymac.com/forum/index.php?showtopic=65786
> Just found this interesting ...

For PC boards it's easy to find ones that do include the chip and ones
that do not.

I cannot tell if the ratio is like 70:30 or 50:50 but both are common.
It seems the TPMs are used more by system integrators that build
complete PC systems than bulk part manufacturers (possibly because of
budget limits and low demand for the chips).

Most PC notebooks include a fingerprint sensor that is tied to a TPM
chip. At least the Windows drivers for the sensor usually require the
TPM drivers installed although I guess the sensor could be used on its
own. There are still many notebooks without a sensor but I have no
idea how many of them do include a TPM chip.

I have no idea why boards with TPM chips are shipped at all or if
anybody uses them for anything but the fingerprint readers.

Thanks

Michal