Source code for pycryptoki.ca_extensions.utilization_metrics

"""
Module to work with utilization metrics
"""
import collections
from ctypes import c_ulong
from pycryptoki.cryptoki import (CA_ReadUtilizationMetrics,
                                 CA_ReadAllUtilizationCounters,
                                 CA_ReadAndResetUtilizationMetrics)
from pycryptoki.cryptoki import CK_UTILIZATION_COUNTER
from pycryptoki.cryptoki import CK_SESSION_HANDLE
from pycryptoki.exceptions import make_error_handle_function

BIN_IDS = {
    0: 'SIGN',
    1: 'VERIFY',
    2: 'ENCRYPT',
    3: 'DECRYPT',
    4: 'KEY_GENERATION',
    5: 'KEY_DERIVATION'
    }

def ca_read_utilization_metrics(session):
    """
    HSM reads utilization data and saves as a snapshot

    :param session: session id that was opened to run the function
    :return: Ret code
    """
    h_session = CK_SESSION_HANDLE(session)
    return CA_ReadUtilizationMetrics(h_session)

ca_read_utilization_metrics_ex = make_error_handle_function(ca_read_utilization_metrics)

def ca_read_and_reset_utilization_metrics(session):
    """
    HSM reads current utilization data and saves as a snapshot;
    HSM resets metrics to zeroes

    :param session: session id that was opened to run the function
    :return: a dictionary with partition serial numbers as keys,
            value - dictionary of utilization metrics
    """
    h_session = CK_SESSION_HANDLE(session)

    return CA_ReadAndResetUtilizationMetrics(h_session)

ca_read_and_reset_utilization_metrics_ex = \
                        make_error_handle_function(ca_read_and_reset_utilization_metrics)

def ca_read_all_utilization_counters(h_session):
    """
        Read Metrics from previously saved HSM snapshot
        Call either functions prior to create snapshot:
        ca_read_utilization_metrics
        ca_read_and_reset_utilization_metrics

        :return: a dictionary, where keys are serial numbers
        and values are dictionaries of bins and values, example: 'SIGN':0
    """
    # Reading length of counters
    length = c_ulong()
    CA_ReadAllUtilizationCounters(h_session, None, length)

    arr = (CK_UTILIZATION_COUNTER * length.value)()
    # Reading actual Metrics
    ret = CA_ReadAllUtilizationCounters(h_session, arr, length)

    # HSM returns a list of dictionaries of all counters
    # Restructuting this list as a dictionary
    partitions = collections.defaultdict(dict)
    for counter in arr:
        partitions[str(counter.ullSerialNumber)]\
                [BIN_IDS[counter.ulBindId]] = counter.ullCount

    return ret, partitions

ca_read_all_utilization_counters_ex = \
                        make_error_handle_function(ca_read_all_utilization_counters)