On Wed, 2021-01-13 at 08:48 +0100, Greg KH wrote: > On Tue, Jan 12, 2021 at 05:59:58PM -0800, 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> > > > > --- > > > > v2: fix TPM 1.2 legacy links failure > > v3: fix warn on and add note to tpm_algorithms > > v4: reword commit and add tested-by > > v5: algorithm spelling fix WARN->dev_err > > --- > > drivers/char/tpm/tpm-sysfs.c | 179 > > +++++++++++++++++++++++++++++++++++ > > include/linux/tpm.h | 9 +- > > 2 files changed, 187 insertions(+), 1 deletion(-) > > You add new sysfs files, but do not add Documentation/ABI/ entries > showing how they are used and what they contain :( > > Please do that for the next version of this patch. It's a bit of a chicken and egg problem since I've no idea when this will go upstream and the entries require that information making the ABI more of a post accept type thing. I can make a guess about the values if Jarkko is going to but this in for the next merge window. James ---8>8>8><8<8<8--- From: James Bottomley <James.Bottomley@xxxxxxxxxxxxxxxxxxxxx> Subject: [PATCH] ABI: add sysfs description for tpm exports of PCR registers Adds the ABI entries for the new /sys/class/tpm/tpm<n>/pcr-<hash>/<m> files which are added to export the PCR hash values on a one value per file basis. Signed-off-by: James Bottomley <James.Bottomley@xxxxxxxxxxxxxxxxxxxxx> --- Documentation/ABI/stable/sysfs-class-tpm | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/Documentation/ABI/stable/sysfs-class-tpm b/Documentation/ABI/stable/sysfs-class-tpm index 91ca63ec7581..d897ecb9615f 100644 --- a/Documentation/ABI/stable/sysfs-class-tpm +++ b/Documentation/ABI/stable/sysfs-class-tpm @@ -194,3 +194,17 @@ Description: The "tpm_version_major" property shows the TCG spec major version Example output:: 2 + +What: /sys/class/tpm/tpmX/pcr-H/N +Date: March 2021 +KernelVersion: 5.12 +Contact: linux-integrity@xxxxxxxxxxxxxxx +Description: produces output in compact hex representation for PCR + number N from hash bank H. N is the numeric value of + the PCR number and H is the crypto string + representation of the hash + + Example output:: + + cat /sys/class/tpm/tpm0/pcr-sha256/7 + 2ED93F199692DC6788EFA6A1FE74514AB9760B2A6CEEAEF6C808C13E4ABB0D42
