On Tue, Aug 18, 2020 at 07:12:09PM +0300, Jarkko Sakkinen wrote: > On Mon, Aug 17, 2020 at 02:35:06PM -0700, James Bottomley wrote: > > Create sysfs per hash groups with 24 PCR files in them one group, > > named pcr-<hash>, for each agile hash of the TPM. The files are > > plugged in to a PCR read function which is TPM version agnostic, so > > this works also for TPM 1.2 but the hash is only sha1 in that case. > > > > Note: the macros used to create the hashes emit spurious checkpatch > > warnings. Do not try to "fix" them as checkpatch recommends, otherwise > > they'll break. > > > > Signed-off-by: James Bottomley <James.Bottomley@xxxxxxxxxxxxxxxxxxxxx> > > Reviewed-by: Jerry Snitselaar <jsnitsel@xxxxxxxxxx> > > Tested-by: Thiago Jung Bauermann <bauerman@xxxxxxxxxxxxx> > > I have hard time understanding why this is required. > > You can grab the information through /dev/tpm0 just fine. I just think it is principally wrong to add sysfs files if they don't have any measurable value other than perhaps some convenience. It is trival to write only a libc dependent program that outputs PCRs. I think this is essentially an user space problem that is getting sorted out with kernel code. /Jarkko
