def TestInput(input_bytes):
if len(input_bytes) < 12:
return
fdp = atheris.FuzzedDataProvider(input_bytes)
choice = fdp.ConsumeIntInRange(1, 4)
if choice == 1:
cipher = aead.ChaCha20Poly1305(aead.ChaCha20Poly1305.generate_key())
if choice == 2:
cipher = aead.AESGCM(aead.AESGCM.generate_key(bit_length=128))
if choice == 3:
cipher = aead.AESOCB3(aead.AESOCB3.generate_key(bit_length=128))
if choice == 4:
cipher = aead.AESCCM(aead.AESCCM.generate_key(bit_length=128))
msg = fdp.ConsumeBytes(32)
authentext = fdp.ConsumeBytes(32)
nonce = fdp.ConsumeBytes(12)
if len(nonce) < 12:
return
ciphertext = cipher.encrypt(nonce, msg, authentext)
plaintext = cipher.decrypt(nonce, ciphertext, authentext)
assert (plaintext == msg), "Encryption/Decrption error!"
def chacha20_poly1305_decrypt(*,
key: bytes,
nonce: bytes,
associated_data: bytes = None,
data: bytes) -> bytes:
assert isinstance(key, (bytes, bytearray))
assert isinstance(nonce, (bytes, bytearray))
assert isinstance(associated_data, (bytes, bytearray, type(None)))
assert isinstance(data, (bytes, bytearray))
assert len(key) == 32, f"unexpected key size: {len(key)} (expected: 32)"
assert len(
nonce) == 12, f"unexpected nonce size: {len(nonce)} (expected: 12)"
if HAS_CRYPTODOME:
cipher = CD_ChaCha20_Poly1305.new(key=key, nonce=nonce)
if associated_data is not None:
cipher.update(associated_data)
# raises ValueError if not valid (e.g. incorrect MAC)
return cipher.decrypt_and_verify(ciphertext=data[:-16],
received_mac_tag=data[-16:])
if HAS_CRYPTOGRAPHY:
a = CG_aead.ChaCha20Poly1305(key)
try:
return a.decrypt(nonce, data, associated_data)
except cryptography.exceptions.InvalidTag as e:
raise ValueError("invalid tag") from e
raise Exception("no chacha20 backend found")
def get_aead_cipher(key, method):
'''get_aead_cipher
method should be AEAD method'''
if method.startswith('aes'):
return aead.AESGCM(key)
try:
return aead.ChaCha20Poly1305(key)
except Exception:
from .ctypes_libsodium import SodiumAeadCrypto
return SodiumAeadCrypto(method, key)
def chacha20_poly1305_encrypt(*, key: bytes, nonce: bytes, associated_data: bytes, data: bytes) -> bytes:
assert isinstance(key, (bytes, bytearray))
assert isinstance(nonce, (bytes, bytearray))
assert isinstance(associated_data, (bytes, bytearray))
assert isinstance(data, (bytes, bytearray))
if HAS_CRYPTODOME:
cipher = CD_ChaCha20_Poly1305.new(key=key, nonce=nonce)
cipher.update(associated_data)
ciphertext, mac = cipher.encrypt_and_digest(plaintext=data)
return ciphertext + mac
if HAS_CRYPTOGRAPHY:
a = CG_aead.ChaCha20Poly1305(key)
return a.encrypt(nonce, data, associated_data)
raise Exception("no chacha20 backend found")
def chacha20_poly1305_encrypt(*,
key: bytes,
nonce: bytes,
associated_data: bytes = None,
data: bytes) -> bytes:
assert isinstance(key, (bytes, bytearray))
assert isinstance(nonce, (bytes, bytearray))
assert isinstance(associated_data, (bytes, bytearray, type(None)))
assert isinstance(data, (bytes, bytearray))
assert len(key) == 32, f"unexpected key size: {len(key)} (expected: 32)"
assert len(
nonce) == 12, f"unexpected nonce size: {len(nonce)} (expected: 12)"
if HAS_CRYPTODOME:
cipher = CD_ChaCha20_Poly1305.new(key=key, nonce=nonce)
if associated_data is not None:
cipher.update(associated_data)
ciphertext, mac = cipher.encrypt_and_digest(plaintext=data)
return ciphertext + mac
if HAS_CRYPTOGRAPHY:
a = CG_aead.ChaCha20Poly1305(key)
return a.encrypt(nonce, data, associated_data)
raise Exception("no chacha20 backend found")
# prompt for input on stderr
def einput(text):
sys.stderr.write(text)
return input()
# getpass and encode
passwd = lambda prompt='Enter Password: '******'utf-8')
# split string at index
split = lambda string, index: (string[:index], string[index:])
# get aead cipher depending on arguments
aead = lambda key, cipher: AEAD.AESGCM(key) if cipher == Aenker.cipher_t.Value(
'AESGCM') else AEAD.ChaCha20Poly1305(key)
# key derivation wrappers
class KDF:
argon2 = lambda password, blob :\
split(argon2_raw(password, blob.nonce, \
blob.kdf_opts.time_cost, 2**blob.kdf_opts.memory_cost, blob.kdf_opts.parallelism, \
hash_len=44, type=argon2_type.I), 12)
# parse commandline arguments
argparser = argparse.ArgumentParser()
# arg_grp: input / output files
def decrypt(cls, ciphertext_and_tag, aad, key, iv):
try:
return aead.ChaCha20Poly1305(key).decrypt(iv, ciphertext_and_tag,
aad)
except cryptography.exceptions.InvalidTag:
raise ProtectionInvalid("Tag invalid")
def encrypt(cls, plaintext, aad, key, iv):
return aead.ChaCha20Poly1305(key).encrypt(iv, plaintext, aad)
def get_aead_cipher(key, method):
'''get_aead_cipher
method should be AEAD method'''
if method.startswith('aes'):
return aead.AESGCM(key)
return aead.ChaCha20Poly1305(key)
def __init__(self, reader, key, info, chunksize=1984):
self.reader = reader
self.cipher = aead.ChaCha20Poly1305(key)
self.info = info
self.chunksize = chunksize + 16
self.i = 0
