Low-Level Software: Using BIOS and TDDL Directly
Most of this book discusses programming to high-level interfaces to the TPM. But in order to take advantage of the log recording and trusted boot capabilities of a TPM, it is necessary to talk directly to the chip before even a device driver interface is available, or before the full TSS services are available. In this case, the programmer must talk to the chip either through the BIOS or the TDDL. This chapter shows how to do that.
Talking to the TPM Through BIOS
After an operating system is loaded, a device driver handles communication with the TPM. During the boot of the operating system, however, the boot loader program, such as grub, must measure all bootstrap and operating system ...