[tc] info digest Trustedgrub

[Salvatore Caratozzolo]

ragazzi mi ha risposto Marcel, vi riporto le informazioni 
che ci interessano:

stage1 uses a BIOS-call to use the TPMs SHA1-functionality 
to hash stage2
TG calls the BIOS, which calls the TPM.

> also stage 2 uses CRTM-call (right?) to use TPMs SHA1-functionality to
> hash kernel and so on?

No, in stage2 (the second part) I implemented SHA1 in 
software, since it is much
quicker, then ;) Imagine you measure a ramdisk with 100MB, 
you can't send it to
the TPM in a reasonable amount of time, therefore the 
software solution.

quindi MBR (stage 1 di TG) utilizza il CRTM, stage 2 
invece utilizza una sua implementazione software perchè + 
veloce!