def __init__(self, device_name):
entropysource.EntropySource.__init__(self)
self.qrng = WesQrng()
self.device_name = device_name
try:
self.qrng.wesQrngCreate(self.device_name, "eWesQrngModeDefault")
except eWesQrngError as error:
logging.error(error.msg)
raise
class QRNGSource(entropysource.EntropySource):
'''Entropy source based on QRNG'''
def __init__(self, device_name):
entropysource.EntropySource.__init__(self)
self.qrng = WesQrng()
self.device_name = device_name
try:
self.qrng.wesQrngCreate(self.device_name, "eWesQrngModeDefault")
except eWesQrngError as error:
logging.error(error.msg)
raise
def get_name(self):
'''Get name of entropy source for use in statistics'''
return 'QRNG%s' % self.device_name
def get_entropy_input(self, security_strength,
min_bits, max_bits,
prediction_resistance):
min_bytes = (min_bits + 7) / 8
try:
ctr = 0
random_bytes = ''
while len(random_bytes) < min_bytes and ctr < 10:
random_bytes += (
self.qrng.wesQrngEntropyGet(min_bytes - len(random_bytes)))
ctr += 1
logging.debug("Got %s bytes from qrng.", len(random_bytes))
random_bytes = utilities.binstr_leftmost(random_bytes, max_bits)
if len(random_bytes) >= min_bytes:
self.total_bytes += len(random_bytes)
return 'SUCCESS', random_bytes
else:
return 'ERROR', ("Unable to get the requested entropy. " +
"Only got %s bytes." % len(random_bytes))
except eWesQrngError as error:
logging.error(error.msg)
raise
def close_entropy_source(self):
self.qrng.wesQrngDestroy()