tpm2_pcrevent

Section: General Commands Manual (1)
Updated: SEPTEMBER 2017
Page Index

NAME

tpm2_pcrevent(1) - hashes a file and optionally extends a pcr.

SYNOPSIS

tpm2_pcrevent [OPTIONS] [FILE]

DESCRIPTION

tpm2_pcrevent(1) hashes FILE if specified or stdin. It uses all of the hashing algorithms that the tpm supports. Optionally, if a pcr index is specified, it extends that pcr for all supported algorithms with the hash digest. In either case, it outputs to stdout the hash algorithm used and the digest value, one per line:

alg:digest

Where alg is the algorithm used (eg. sha1) and digest is the digest resulting from the hash computation of alg on the data.

See sections 23.1 and sections 17 of the TPM2.0 Specification (https://trustedcomputinggroup.org/wp-content/uploads/TPM-Rev-2.0-Part-3-Commands-01.38.pdf)

OPTIONS

These options control extending the pcr:

•: -i, -pcr-index=INDEX: Not only compute the hash digests on FILE, also extend the pcr given by INDEX for all supported hash algorithms.
•: -S, -input-session-handle=SESSION_HANDLE: Use SESSION_HANDLE for providing an authorization session for the pcr specified by INDEX. It is an error to specify -S without specifying a pcr index with -i.
•: -P, -password=PASSWORD: Use PASSWORD for providing an authorization value for the pcr specified in INDEX. It is an error to specify -P without specifying a pcr index with -i.

COMMON OPTIONS

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

•: -h, -help: Display the tools manpage. This 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.
•: -V, -verbose: Increase the information that the tool prints to the console during its execution. When using this option the file and line number are printed.
•: -Q, -quiet: Silence normal tool output to stdout.
•: -Z, -enable-errata: Enable the application of errata fixups. Useful if an errata fixup needs to be applied to commands sent to the TPM. # TCTI ENVIRONMENT

This collection of environment variables that may be used to configure the various TCTI modules available.

The values passed through these variables can be overridden on a per-command basis using the available command line options, see the TCTI_OPTIONS section.

The variables respected depend on how the software was configured.

•

TPM2TOOLS_TCTI_NAME: Select the TCTI used for communication with the next component down the TSS stack. In most configurations this will be the TPM but it could be a simulator or proxy. The current known TCTIs are:

•: tabrmd - The new resource manager, called tabrmd (https://github.com/01org/tpm2-abrmd).
•: socket - Typically used with the old resource manager, or talking directly to a simulator.
•: device - Used when talking directly to a TPM device file.

•

TPM2TOOLS_DEVICE_FILE: When using the device TCTI, specify the TPM device file. The default is "/dev/tpm0".

: Note: Using the tpm directly requires the users to ensure that concurrent access does not occur and that they manage the tpm resources. These tasks are usually managed by a resource manager. Linux 4.12 and greater supports an in kernel resource manager at "/dev/tpmrm", typically "/dev/tpmrm0".

•

TPM2TOOLS_SOCKET_ADDRESS: When using the socket TCTI, specify the domain name or IP address used. The default is 127.0.0.1.

•

TPM2TOOLS_SOCKET_PORT: When using the socket TCTI, specify the port number used. The default is 2321.

TCTI OPTIONS

This collection of options are used to configure the varous TCTI modules available. They override any environment variables.

•

-T, -tcti=TCTI_NAME[:TCTI_OPTIONS]: Select the TCTI used for communication with the next component down the TSS stack. In most configurations this will be the resource manager: tabrmd (https://github.com/01org/tpm2-abrmd) Optionally, tcti specific options can appended to TCTI_NAME by appending a : to TCTI_NAME.

•: For the device TCTI, the TPM device file for use by the device TCTI can be specified. The default is /dev/tpm0. Example: -T device:/dev/tpm0
•: For the socket TCTI, the domain name or IP address and port number used by the socket can be specified. The default are 127.0.0.1 and 2321. Example: -T socket:127.0.0.1:2321
•: For the abrmd TCTI, it takes no options. Example: -T abrmd

EXAMPLES

Hash a file:

tpm2_pcrevent data

Hash a file and extend pcr 8:

tpm2_pcrevent -i 8 data

RETURNS

0 on success or 1 on failure.

BUGS

Github Issues (https://github.com/01org/tpm2-tools/issues)

HELP

See the Mailing List (https://lists.01.org/mailman/listinfo/tpm2)