tpm2_pcrextend man page

tpm2_pcrextend(1) — Extends a PCR.


tpm2_pcrextend [Options] [PCR_DIGEST_SPEC]


tpm2_pcrextend(1) Extends the pcrs with values indicated by PCR_DIGEST_SPEC.

A PCR_DIGEST_SPEC is defined as follows:

Example Digest Specification:


Note: that multiple specifications of PCR and hash are allowed. Multiple hashes cause the pcr to be extended with both hashes. Multiple same PCR values cause the PCR to be extended multiple times. Extension is done in order from left to right as specified. At most 5 hash extensions per PCR entry are supported. This is to keep the parser simple.


This tool accepts no tool specific options.

Common Options

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

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.

Tcti Options

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


Extend PCR 4's SHA1 bank with a hash:

tpm2_pcrextend 4:sha=f1d2d2f924e986ac86fdf7b36c94bcdf32beec15

Extend PCR 4's SHA1 and SHA256 banks with hashes:

tpm2_pcrextend 4:sha=f1d2d2f924e986ac86fdf7b36c94bcdf32beec15,sha256:b5bb9d8014a0f9b1d61e21e796d78dccdf1352f23cd32812f4850b878ae4944c

Extend PCR 4's SHA1 and PCR 7's SHA256 bank with hashes:

tpm2_pcrextend 4:sha=f1d2d2f924e986ac86fdf7b36c94bcdf32beec15 7:sha256:b5bb9d8014a0f9b1d61e21e796d78dccdf1352f23cd32812f4850b878ae4944c


0 on success or 1 on failure.


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SEPTEMBER 2017 tpm2-tools General Commands Manual