% tpm2_getcap(1) tpm2-tools | General Commands Manual


tpm2_getcap(1) - Display TPM capabilities in a human readable form.


tpm2_getcap [OPTIONS] [CAPABILITY]


tpm2_getcap(1) - Query the TPM for it's capabilities / properties and print them to the console. It takes a string form of the capability to query as an argument to the tool. Currently supported capability groups are:

  • algorithms: Display data about supported algorithms.

  • commands: Display data about supported commands.

  • pcrs: Display currently allocated PCRs.

  • properties-fixed: Display fixed TPM properties.

  • properties-variable: Display variable TPM properties.

  • ecc-curves: Display data about elliptic curves.

  • handles-transient: Display handles about transient objects.

  • handles-persistent: Display handles about persistent objects.

  • handles-permanent: Display handles about permanent objects.

  • handles-pcr: Display handles about PCRs.

  • handles-nv-index: Display handles about NV Indices.

  • handles-loaded-session: Display handles about both loaded HMAC and policy sessions.

  • handles-saved-session: Display handles about saved sessions.

  • vendor[:num]: Displays the vendor properties as a hex buffer output. The string "vendor" can be suffixed with a colon followed by a number as understood by strtoul(3) with a 0 base. That value is used as the property value within the\ TPM2_GetCapability command, and defaults to 1. An example to call it with a property value of 2 is: tpm2_getcap vendor:2

NOTE: if vendor requests hang, try the "-i" option to ignore the moreData field and only read once.


  • -l, --list:

    List known supported capability names. These names can be supplied as the argument to the -c option. Output is in a YAML compliant list to stdout.

    For example: - algorithms - commands - properties-fixed ...

  • --ignore-moredata

Ignores the moreData field when dealing with buggy TPM responses.

common options

common tcti options


To list the fixed properties of the TPM

tpm2_getcap properties-fixed

To list the supported capability groups

tpm2_getcap -l