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Precomputation
Daniel Neus edited this page Jul 8, 2015
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Replace 'sdX' in the following commands with the device where you have installed TrustedGRUB2
First compute SHA1 hash of the diskboot.img. It's the first sector after the MBR, i.e. sector 2:
dd if=/dev/sdX bs=512 skip=1 count=1 | sha1sum
PCR8 is then:
PCR8 = sha1sum( 0000000000000000000000000000000000000000 || SHA1 from command above )
For example this command chain could be used to calculate this:
echo -n 000000000000000000000000000000000000000076cd3a3f9d64bdf528054aae025b36b9235d99be | xxd -r -p | sha1sum -b | awk '{print $1}'
First you should determine the size of your core.img. This size is contained in the diskboot.img.
dd if=/dev/sdX bs=1 skip=1020 count=2 | hexdump -d
After this, replace the number of sectors of the core.img in the following command and measure the core.img:
dd if=/dev/sdX bs=512 skip=2 count=NumberOfSectorsCoreIMG | sha1sum
Finally compute PCR9. As explained above for PCR 8.