def tape_gen(self, data):
"""Return a bit string, generated from the given data string"""
# FIXME
data = str(data).encode()
# Derive a key from data
hmac_obj = hmac.HMAC(self.key, digestmod=hashlib.sha256)
hmac_obj.update(data)
assert hmac_obj.digest_size == 32
digest = hmac_obj.digest()
# Use AES in the CTR mode to generate a pseudo-random bit string
aes_algo = algorithms.AES(digest)
aes_cipher = Cipher(aes_algo,
mode=CTR(b'\x00' * 16),
backend=default_backend())
encryptor = aes_cipher.encryptor()
while True:
encrypted_bytes = encryptor.update(b'\x00' * 16)
# Convert the data to a list of bits
bits = util.str_to_bitstring(encrypted_bytes)
for bit in bits:
yield bit
def tape_gen(self, data):
"""Return a bit string, generated from the given data string"""
# FIXME
data = str(data).encode()
# Derive a key
hmac_obj = hmac.HMAC(self.key, digestmod=hashlib.sha256)
hmac_obj.update(data)
assert hmac_obj.digest_size == 32
digest = hmac_obj.digest()
# Use AES-CTR cipher to generate a pseudo-random bit string
aes_cipher = AES.new(digest, AES.MODE_CTR, counter=Counter.new(nbits=128))
while True:
encrypted_bytes = aes_cipher.encrypt(b'\x00' * 16)
# Convert the data to a list of bits
bits = util.str_to_bitstring(encrypted_bytes)
for bit in bits:
yield bit
def test_bit_string_conversion():
assert str_to_bitstring(b'') == []
assert str_to_bitstring(b'A') == [0, 1, 0, 0, 0, 0, 0, 1]
assert str_to_bitstring(b'AB') == [0, 1, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 1, 0]
def test_bit_string_conversion():
assert str_to_bitstring(b'') == []
assert str_to_bitstring(b'A') == [0, 1, 0, 0, 0, 0, 0, 1]
assert str_to_bitstring(b'AB') == [
0, 1, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 1, 0
]