policy

class tpm2_pytss.policy(policy, hash_alg)

Initialize policy object.

Parameters:

• policy (Union(bytes, str]) – The JSON policy to calculate or execute.

• hash_alg (TPM2_ALG) – The hash algorithm to use for policy calculations.

Returns:

An instance of the policy object.

This class implements the policy part of the TCG TSS 2.0 JSON Data Types and Policy Language Specification.

The specification can be found at https://trustedcomputinggroup.org/resource/tcg-tss-json/

calculate()

Calculate the policy

Raises:

TSS2_Exception –

close()

Finalize the policy instance

property description

The policy description.

Type:

bytes

execute(esys_ctx, session)

Executes the policy

Parameters:

• esys_ctx (ESAPI) – The ESAPI instance to use during policy execution.

• session (ESYS_TR) – The policy session to use during execution.

Raises:

TSS2_Exception or any possible exception from a callback function. –

get_calculated_digest()

Get the digest of the calculated policy

Returns:

The digest as a TPM2B_DIGEST.

Raises:

TSS2_Exception –

get_calculated_json()

Get the calculated policy as JSON

Returns:

The calculated JSON policy as bytes

Raises:

TSS2_Exception –

property hash_alg

The hash algorithm to be used during policy calculcation.

Type:

TPM2_ALG

property policy

The JSON policy.

Type:

bytes

set_callback(callback_type, callback)

Set callback for policy calculaction or execution

Parameters:

• callback_type (policy_cb_types) – Which callback to set or unset.

• callback (Union[None, Callable]) – The callback function to call, or None to remove the callback.

Raises:

ValueError –