> Verify the ROMs integrity in that first stage (...) need open firmware or some mechanism to hash the ROM that is installed, you need to have a means to read it in its entirety"
Does such a mechanism exist? If you can do this[1] from BIOS, why is it safe to assume that the same can't be done for the dump-bios-image routine? AFAIK the BIOS handles this in real-mode [2] (overrides the OS), and "returns" the image by copying it somewhere in low memory. So, you're trusting the BIOS that it's copied the right data out for you. (goodguybios)
> I say open firmware because you need to be able to guarantee the FBI couldn't embed a backdoor firmware.
This reminds me of this NSA RAID controller rootkit for Dell Poweredge Servers [3]. Nuts. Every closed firmware on your servers is a potential hiding place to someone with (soldering-iron-to-the-motherboard) physical access.
In our Dread Pirate use case, you don't even have to think that far as you can't ensure your own BIOS. Who are you going to buy TPM servers [4] from, when you're defending against the FBI? Intel? HP?
The Rootkit wikipedia page is alarming, to say the least. [5]
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[1] A Real SMM Rootkit: Reversing and Hooking BIOS SMI Handlers http://phrack.org/issues/66/11.html#article
[2] http://en.wikipedia.org/wiki/Real_mode
[3] http://resources.infosecinstitute.com/nsa-bios-backdoor-god-...
[4] http://en.wikipedia.org/wiki/Trusted_Platform_Module
[5] http://en.wikipedia.org/wiki/Rootkit#Bootkits ("Bootkits??")
[6] https://www.blackhat.com/presentations/bh-usa-07/Heasman/Pre...