DOKK / manpages / debian 12 / tpm2-tools / tss2_pcrread.1.en
tss2_pcrread(1) General Commands Manual tss2_pcrread(1)

tss2_pcrread(1) -

tss2_pcrread [OPTIONS]

fapi-config(5) to adjust Fapi parameters like the used cryptographic profile and TCTI or directories for the Fapi metadata storages.

fapi-profile(5) to determine the cryptographic algorithms and parameters for all keys and operations of a specific TPM interaction like the name hash algorithm, the asymmetric signature algorithm, scheme and parameters and PCR bank selection.

tss2_pcrread(1) - This command provides a PCRs value and corresponding event log. The PCR bank to be used per PCR is defined in the cryptographic profile (cf., fapi-profile(5)).

These are the available options:

•
-o, --pcrValue=FILENAME or - (for stdout):

Returns PCR digest. Optional parameter.

•
-x, --pcrIndex=INTEGER:

Identifies the PCR to read.

•
-f, --force:

Force overwriting the output files.

•
-l, --pcrLog=FILENAME or - (for stdout):

Returns the PCR log for that PCR. Optional parameter.

PCR event logs are a list (arbitrary length JSON array) of log entries with the following content.

- recnum: Unique record number
- pcr: PCR index
- digest: The digests
- type: The type of event. At the moment the only possible value is: "LINUX_IMA" (legacy IMA)
- eventDigest: Digest of the event; e.g. the digest of the measured file
- eventName: Name of the event; e.g. the name of the measured file.

This collection of options are common to all tss2 programs and provide information that many users may expect.

•
-h, --help [man|no-man]: Display the tools manpage. By default, it attempts to invoke the manpager for the tool, however, on failure will output a short tool summary. This is the same behavior if the “man” option argument is specified, however if explicit “man” is requested, the tool will provide errors from man on stderr. If the “no-man” option if specified, or the manpager fails, the short options will be output to stdout.

To successfully use the manpages feature requires the manpages to be installed or on MANPATH, See man(1) for more details.

•
-v, --version: Display version information for this tool, supported tctis and exit.

tss2_pcrread --pcrIndex=16 --pcrValue=pcrValue.file --pcrLog=pcrLog.file

0 on success or 1 on failure.

Github Issues (https://github.com/tpm2-software/tpm2-tools/issues)

See the Mailing List (https://lists.linuxfoundation.org/mailman/listinfo/tpm2)

APRIL 2019 tpm2-tools