def verifyThenDecrypt(cipher, emailTime, key):
encryptKey = key[16:]
signKey = key[:16]
payload = base64.urlsafe_b64decode(cipher)
#verify timestamp to prevent replay
try:
timestamp, = struct.unpack(">Q", payload[1:9])
except struct.error:
raise ValueError('Invalid message')
if timestamp + TTL < emailTime:
raise Exception('Invalid timestamp: replay attack detected')
#verify HMAC
hasher = HMAC(signKey, hashes.SHA256(), backend=default_backend())
hasher.update(payload[:-32])
try:
hasher.verify(payload[-32:])
except InvalidSignature:
raise Exception('Invalid HMAC: data modification detected')
#decrypt cipher text
iv = payload[9:25]
ciphertext = payload[25:-32]
decryptor = Cipher(algorithms.AES(encryptKey), modes.CBC(iv),
default_backend()).decryptor()
paddedPlaintext = decryptor.update(ciphertext)
paddedPlaintext += decryptor.finalize()
unpadder = padding.PKCS7(algorithms.AES.block_size).unpadder()
plaintext = unpadder.update(paddedPlaintext)
plaintext += unpadder.finalize()
return plaintext
def check_integrity(self, token, ttl=None):
# check integrity of files
# with our implementation, this is actually superfluous, since if the integrity is compromised, you can't get to
# this function. We check the integrity when we decrypt.
if not isinstance(token, bytes):
raise TypeError("token must be bytes.")
current_time = int(time.time())
try:
data = base64.urlsafe_b64decode(token)
except (TypeError, binascii.Error):
raise InvalidToken
if not data or six.indexbytes(data, 0) != 0x80:
raise InvalidToken
try:
timestamp, = struct.unpack(">Q", data[1:9])
except struct.error:
raise InvalidToken
if ttl is not None:
if timestamp + ttl < current_time:
raise InvalidToken
if current_time + _MAX_CLOCK_SKEW < timestamp:
raise InvalidToken
h = HMAC(self._signing_key, hashes.SHA512(), backend=self._backend)
h.update(data[:-64])
try:
h.verify(data[-64:])
except InvalidSignature:
raise InvalidToken
def _decrypt_data(self, data, timestamp, ttl):
current_time = int(time.time())
if ttl is not None:
if timestamp + ttl < current_time:
raise InvalidToken
if current_time + _MAX_CLOCK_SKEW < timestamp:
raise InvalidToken
h = HMAC(self._signing_key, hashes.SHA256(), backend=self._backend)
h.update(data[:-32])
try:
h.verify(data[-32:])
except InvalidSignature:
raise InvalidToken
iv = data[9:25]
ciphertext = data[25:-32]
decryptor = Cipher(
algorithms.AES(self._encryption_key), modes.CBC(iv), self._backend
).decryptor()
plaintext_padded = decryptor.update(ciphertext)
try:
plaintext_padded += decryptor.finalize()
except ValueError:
raise InvalidToken
unpadder = padding.PKCS7(algorithms.AES.block_size).unpadder()
unpadded = unpadder.update(plaintext_padded)
try:
unpadded += unpadder.finalize()
except ValueError:
raise InvalidToken
return unpadded
def _verify_signature(self, data):
h = HMAC(self._signing_key, hashes.SHA256(), backend=self._backend)
h.update(data[:-32])
try:
h.verify(data[-32:])
except InvalidSignature:
raise InvalidToken
def checkHMAC(self, fp, segments_start, segments_end, fileHMAC):
'''Check the file's integrity'''
filehash = HMAC(self.hmackey, primitives.hashes.SHA256(), backend)
filehash.update(self.FileMACPrefix)
for segmentIndex, startpos, datalen in self.segment_ranges(
segments_start, segments_end):
print(" Segment %d" % (segmentIndex))
fp.seek(startpos)
segmentIV = fp.read(self.SegIVLen)
segmentMAC = fp.read(self.SegMACLen)
# Verify the segment's own MAC against the segment data
segmenthash = HMAC(self.hmackey, primitives.hashes.SHA256(),
backend)
segmenthash.update(segmentIV)
segmenthash.update(struct.pack('>I', segmentIndex))
segmenthash.update(fp.read(datalen))
# The cryptography module doesn't handle truncated HMACs directly
computed = segmenthash.finalize()
# print(computed.decode("utf-8"))
assert primitives.constant_time.bytes_eq(computed[:self.SegMACLen],
segmentMAC)
# Add the segment's MAC to the file-MAC context
filehash.update(segmentMAC)
# Finally, verify the file MAC
print(" File hash")
filehash.verify(fileHMAC) # Raises on mismatch.
def decrypt(privkey, data):
s = serialize.Deserializer(data)
iv = s.bytes(16)
curve = s.uint(2)
assert curve == 0x02ca
x_len = s.uint(2)
assert x_len <= 32 # TODO Should we assert this? And should we assert no leading zero bytes?
x = s.bytes(x_len)
y_len = s.uint(2)
assert y_len <= 32 # TODO Should we assert this? And should we assert no leading zero bytes?
y = s.bytes(y_len)
encrypted = s.bytes(-32)
assert encrypted != b''
mac = s.bytes(32)
pubkey = x.rjust(32, b'\x00') + y.rjust(32, b'\x00')
public_key = _pub_to_public(pubkey)
private_key = _priv_to_private(privkey)
secret = private_key.exchange(ec.ECDH(), public_key)
key = hashlib.sha512(secret).digest()
enckey = key[0:32]
mackey = key[32:64]
maccer = HMAC(mackey, hashes.SHA256(), openssl.backend)
maccer.update(data[0:-32])
maccer.verify(mac)
cipher = Cipher(algorithms.AES(enckey), modes.CBC(iv), openssl.backend)
decryptor = cipher.decryptor()
padded = decryptor.update(encrypted) + decryptor.finalize()
unpadder = padding.PKCS7(128).unpadder()
return unpadder.update(padded) + unpadder.finalize()
def verifyThenDecrypt(cipher, emailTime, key):
encryptKey = key[16:]
signKey = key[:16]
payload = base64.urlsafe_b64decode(cipher)
#verify timestamp to prevent replay
try:
timestamp, = struct.unpack(">Q", payload[1:9])
except struct.error:
raise ValueError('Invalid message')
if timestamp + TTL < emailTime:
raise Exception('Invalid timestamp: replay attack detected')
#verify HMAC
hasher = HMAC(signKey, hashes.SHA256(), backend=default_backend())
hasher.update(payload[:-32])
try:
hasher.verify(payload[-32:])
except InvalidSignature:
raise Exception('Invalid HMAC: data modification detected')
#decrypt cipher text
iv = payload[9:25]
ciphertext = payload[25:-32]
decryptor = Cipher(algorithms.AES(encryptKey), modes.CBC(iv), default_backend()).decryptor()
paddedPlaintext = decryptor.update(ciphertext)
paddedPlaintext += decryptor.finalize()
unpadder = padding.PKCS7(algorithms.AES.block_size).unpadder()
plaintext = unpadder.update(paddedPlaintext)
plaintext += unpadder.finalize()
return plaintext
def checkHMAC(self, fp, segments_start, segments_end, fileHMAC):
'''Check the file's integrity'''
filehash = HMAC(self.hmackey, primitives.hashes.SHA256(), backend)
filehash.update(self.FileMACPrefix)
for segmentIndex, startpos, datalen in self.segment_ranges(segments_start, segments_end):
print(" Segment %d" % (segmentIndex))
fp.seek(startpos)
segmentIV = fp.read(self.SegIVLen)
segmentMAC = fp.read(self.SegMACLen)
# Verify the segment's own MAC against the segment data
segmenthash = HMAC(self.hmackey, primitives.hashes.SHA256(), backend)
segmenthash.update(segmentIV)
segmenthash.update(struct.pack('>I', segmentIndex))
segmenthash.update(fp.read(datalen))
# The cryptography module doesn't handle truncated HMACs directly
computed = segmenthash.finalize()
assert primitives.constant_time.bytes_eq(computed[:self.SegMACLen], segmentMAC)
# Add the segment's MAC to the file-MAC context
filehash.update(segmentMAC)
# Finally, verify the file MAC
print(" File hash")
filehash.verify(fileHMAC) # Raises on mismatch.
def _verify_signature(self, data):
h = HMAC(self._signing_key, hashes.SHA256(), backend=self._backend)
h.update(data[:-32])
try:
h.verify(data[-32:])
except InvalidSignature:
raise InvalidToken
def _decrypt_data(self, data, timestamp, ttl):
current_time = int(time.time())
if ttl is not None:
if timestamp + ttl < current_time:
raise InvalidToken
if current_time + _MAX_CLOCK_SKEW < timestamp:
raise InvalidToken
h = HMAC(self._signing_key, hashes.SHA256(), backend=self._backend)
h.update(data[:-32])
try:
h.verify(data[-32:])
except InvalidSignature:
raise InvalidToken
iv = data[9:25]
ciphertext = data[25:-32]
decryptor = Cipher(algorithms.AES(self._encryption_key), modes.CBC(iv),
self._backend).decryptor()
plaintext_padded = decryptor.update(ciphertext)
try:
plaintext_padded += decryptor.finalize()
except ValueError:
raise InvalidToken
unpadder = padding.PKCS7(algorithms.AES.block_size).unpadder()
unpadded = unpadder.update(plaintext_padded)
try:
unpadded += unpadder.finalize()
except ValueError:
raise InvalidToken
return unpadded
def decrypt(privkey, data):
s = serialize.Deserializer(data)
iv = s.bytes(16)
curve = s.uint(2)
assert curve == 0x02ca
x_len = s.uint(2)
assert x_len <= 32 # TODO Should we assert this? And should we assert no leading zero bytes?
x = s.bytes(x_len)
y_len = s.uint(2)
assert y_len <= 32 # TODO Should we assert this? And should we assert no leading zero bytes?
y = s.bytes(y_len)
encrypted = s.bytes(-32)
assert encrypted != b''
mac = s.bytes(32)
pubkey = x.rjust(32, b'\x00') + y.rjust(32, b'\x00')
public_key = _pub_to_public(pubkey)
private_key = _priv_to_private(privkey)
secret = private_key.exchange(ec.ECDH(), public_key)
key = hashlib.sha512(secret).digest()
enckey = key[0:32]
mackey = key[32:64]
maccer = HMAC(mackey, hashes.SHA256(), openssl.backend)
maccer.update(data[0:-32])
maccer.verify(mac)
cipher = Cipher(algorithms.AES(enckey), modes.CBC(iv), openssl.backend)
decryptor = cipher.decryptor()
padded = decryptor.update(encrypted) + decryptor.finalize()
unpadder = padding.PKCS7(128).unpadder()
return unpadder.update(padded) + unpadder.finalize()
def _verify_signature(self, data: bytes) -> None:
h = HMAC(self._signing_key, hashes.SHA256())
h.update(data[:-32])
try:
h.verify(data[-32:])
except InvalidSignature:
raise InvalidToken
class FernetDecryptMiddleware(BaseMiddleware):
""" Decrypt data based on Fernet from the Cryptography library.
- Algorithm: AES-128
- Mode: CBC
- Padding: PKCS#7
- MAC: SHA-256, Encrypt-then-MAC
- Key: User-provided
- IV: First 16-bytes of data
"""
readable = True
def __init__(self, key, iv=None):
self.key = key
self.iv = iv
self.check = b''
self.decryptor = None
self.unpadder = padding.PKCS7(algorithms.AES.block_size).unpadder()
self.hmac = HMAC(key[:16], hashes.SHA256(), backend=default_backend())
def flush(self):
if self.decryptor:
data = self.decryptor.finalize()
self.decryptor = None
self.hmac.update(data)
self.hmac.verify(self.check)
if data:
return self.unpadder.update(data) + self.unpadder.finalize()
else:
return self.unpadder.finalize()
return b''
def read(self, data):
if not self.decryptor:
if len(data) < 16:
self.iv = data
return b''
else:
self.iv = data[:16]
data = data[16:]
self.decryptor = Cipher(algorithms.AES(self.key[16:]),
modes.CBC(self.iv),
backend=default_backend()).decryptor()
if not data:
return b''
data = self.check + data
self.check = data[-32:]
data = data[:-32]
self.hmac.update(data)
data = self.decryptor.update(data)
return self.unpadder.update(data)
def _verify(data, mac_key):
h = HMAC(mac_key, _MAC_HASH, _backend)
h.update(data[:-_MAC_LEN])
try:
h.verify(data[-_MAC_LEN:])
return True
except InvalidSignature:
return False
def decrypt(self: SSSSData, key: SSSSKey, name: str) -> bytes:
keys = key.derive_keys(name)
ct = self.ciphertext
hm = HMAC(keys.hmac_key, SHA256(), backend = default_backend())
hm.update(ct)
hm.verify(self.mac)
iv = IV(self.iv)
return aes256ctr(iv, keys.aes_key, ct)
def _check_hmac(
halg: hashes.HashAlgorithm,
hmackey: bytes,
enc_cred: bytes,
name: bytes,
expected: bytes,
):
h = HMAC(hmackey, halg(), backend=default_backend())
h.update(enc_cred)
h.update(name)
h.verify(expected)
def decrypt(self, token, ttl=None):
if not isinstance(token, bytes):
raise TypeError("token must be bytes.")
current_time = int(time.time())
try:
data = base64.urlsafe_b64decode(token)
except (TypeError, binascii.Error):
raise InvalidToken
if not data or six.indexbytes(data, 0) != 0x80:
raise InvalidToken
try:
timestamp, = struct.unpack(">Q", data[1:9])
except struct.error:
raise InvalidToken
if ttl is not None:
if timestamp + ttl < current_time:
raise InvalidToken
if current_time + _MAX_CLOCK_SKEW < timestamp:
print (">>>", current_time)
print (">>>", timestamp)
raise InvalidToken
h = HMAC(self._signing_key, hashes.SHA256(), backend=self._backend)
h.update(data[:-32])
try:
# verify everything in data except for tag is the same as original
h.verify(data[-32:])
except InvalidSignature:
raise InvalidToken
iv = data[9:25]
ciphertext = data[25:-32]
decryptor = Cipher(
algorithms.AES(self._encryption_key), modes.CBC(iv), self._backend
).decryptor()
plaintext_padded = decryptor.update(ciphertext)
try:
plaintext_padded += decryptor.finalize()
except ValueError:
raise InvalidToken
unpadder = padding.PKCS7(algorithms.AES.block_size).unpadder()
unpadded = unpadder.update(plaintext_padded)
try:
unpadded += unpadder.finalize()
except ValueError:
raise InvalidToken
return unpadded
def decrypt(self, token, ttl=None):
if not isinstance(token, bytes):
raise TypeError("token must be bytes.")
current_time = int(time.time())
try:
data = base64.urlsafe_b64decode(token)
except (TypeError, binascii.Error):
raise InvalidToken
if not data or six.indexbytes(data, 0) != 0x80:
raise InvalidToken
try:
timestamp, = struct.unpack(">Q", data[1:9])
except struct.error:
raise InvalidToken
if ttl is not None:
if timestamp + ttl < current_time:
raise InvalidToken
if current_time + _MAX_CLOCK_SKEW < timestamp:
print(">>>", current_time)
print(">>>", timestamp)
raise InvalidToken
h = HMAC(self._signing_key, hashes.SHA256(), backend=self._backend)
h.update(data[:-32])
try:
# verify everything in data except for tag is the same as original
h.verify(data[-32:])
except InvalidSignature:
raise InvalidToken
iv = data[9:25]
ciphertext = data[25:-32]
decryptor = Cipher(algorithms.AES(self._encryption_key), modes.CBC(iv),
self._backend).decryptor()
plaintext_padded = decryptor.update(ciphertext)
try:
plaintext_padded += decryptor.finalize()
except ValueError:
raise InvalidToken
unpadder = padding.PKCS7(algorithms.AES.block_size).unpadder()
unpadded = unpadder.update(plaintext_padded)
try:
unpadded += unpadder.finalize()
except ValueError:
raise InvalidToken
return unpadded
def verify_signature_hmac(signature, key, data):
dt = _get_digest(signature.signature.hmac.hashAlg)
if dt is None:
raise ValueError(
f"unsupported digest algorithm: {signature.signature.hmac.hashAlg}"
)
sh = hashes.Hash(dt(), backend=default_backend())
sh.update(data)
hdata = sh.finalize()
sig = bytes(signature.signature.hmac)
h = HMAC(key, dt(), backend=default_backend())
h.update(hdata)
h.verify(sig)
def compare(self, hmac, snowflake, secret):
if not isinstance(hmac, bytes):
hmac = base64.urlsafe_b64decode(hmac)
if not isinstance(secret, bytes):
secret = str(secret).encode()
compare_hmac = HMAC(secret, hashes.SHA256(), backend=default_backend())
compare_hmac.update(struct.pack('l', int(snowflake)))
try:
compare_hmac.verify(hmac)
return True
except:
return False
def verify_mac(key, packed_data, algorithm="SHA256", backend=BACKEND):
""" Verifies a message authentication code as obtained by apply_mac.
Successful comparison indicates integrity and authenticity of the data.
Returns data is comparison succeeds; Otherwise returns pride.functions.security.INVALID_TAG. """
mac, data = load_data(packed_data)
hasher = HMAC(key, getattr(hashes, algorithm.upper())(), backend=backend)
hasher.update(algorithm + '::' + data)
try:
hasher.verify(mac)
except InvalidSignature:
return INVALID_TAG
else:
return data
def decrypt_and_unpack(
input_file: IOIter,
output_file: IOIter,
key_pair: Optional[bytes],
options: OptionsDict,
) -> None:
""" Read encrypted, GZIPed data from an open file descriptor, and write the decoded data to
another file descriptor; verify the HMAC of the encrypted data to ensure integrity
:param input_file: an IOIter object to read compressed ciphertext from
:param output_file: an IOIter object to write plaintext data to
"""
key, nonce, signature = (
key_pair[:AES_KEY_SIZE],
key_pair[AES_KEY_SIZE:AES_KEY_SIZE + AES_BLOCK_SIZE],
key_pair[AES_KEY_SIZE + AES_BLOCK_SIZE:]
) if key_pair else (b'', b'', b'')
decrypted_data = b''
decrypt_fn: Callable[[bytes], bytes] = (
Cipher(AES(key), CTR(nonce), backend=default_backend()).decryptor().update
if options['use_encryption'] else identity
)
decompress_obj = zlib.decompressobj()
unzip_fn: Callable[[bytes], bytes] = (
decompress_obj.decompress # type: ignore
if options['use_compression'] else identity
)
hmac = HMAC(key, SHA256(), default_backend())
writer = output_file.writer(); next(writer)
for encrypted_data in input_file.reader():
if options['use_encryption']:
hmac.update(encrypted_data)
decrypted_data += decrypt_fn(encrypted_data)
logger.debug2(f'decrypt_fn returned {len(decrypted_data)} bytes')
block = unzip_fn(decrypted_data)
logger.debug2(f'unzip_fn returned {len(block)} bytes')
writer.send(block)
decrypted_data = decompress_obj.unused_data
# Decompress and write out the last block
if decrypted_data:
block = unzip_fn(decrypted_data)
logger.debug2(f'unzip_fn returned {len(block)} bytes')
writer.send(block)
try:
if options['use_encryption']:
hmac.verify(signature)
except InvalidSignature as e:
raise BackupCorruptedError("The file's signature did not match the data") from e
def verify_mac(key, packed_data, algorithm="SHA256", backend=BACKEND):
""" Verifies a message authentication code as obtained by apply_mac.
Successful comparison indicates integrity and authenticity of the data.
Returns data is comparison succeeds; Otherwise returns pride.functions.security.INVALID_TAG. """
mac, data = load_data(packed_data)
hasher = HMAC(key,
getattr(hashes, algorithm.upper())(),
backend=backend)
hasher.update(algorithm + '::' + data)
try:
hasher.verify(mac)
except InvalidSignature:
return INVALID_TAG
else:
return data
def opdata1_verify_overall_hmac(hmac_key, item):
verifier = HMAC(hmac_key, SHA256(), backend=_backend)
for key, value in sorted(item.items()):
if key == 'hmac':
continue
if isinstance(value, bool):
value = str(int(value)).encode('utf-8')
else:
value = str(value).encode('utf-8')
verifier.update(key.encode('utf-8'))
verifier.update(value)
expected = base64.b64decode(item['hmac'])
try:
verifier.verify(expected)
except InvalidSignature:
raise ValueError("HMAC did not match for data dictionary")
def MydecryptMAC(c, tag, iv, enckey, HMACKey):
if len(HMACKey) != KEY_BYTES:
sys.stderr.write('Error: Key length must be 32 bytes.')
else:
# generates new tag
tagPrime = HMAC(HMACKey, hashes.SHA256(), backend=default_backend())
tagPrime.update(c)
# verifies tags match
# errors if false
tagPrime.verify(tag)
# decrypts message after tag verification
message = mydecrypt(c, iv, enckey)
print('... Finished mydecrypt (mac)')
return message
def opdata1_decrypt_key(data, key, hmac_key, aes_size=C_AES_SIZE, ignore_hmac=False):
"""Decrypt encrypted item keys"""
hmac_key = make_utf8(hmac_key)
key_size = KEY_SIZE[aes_size]
iv, cryptext, expected_hmac = struct.unpack("=16s64s32s", data)
if not ignore_hmac:
verifier = HMAC(hmac_key, SHA256(), backend=_backend)
verifier.update(iv + cryptext)
try:
verifier.verify(expected_hmac)
except InvalidSignature:
raise ValueError("HMAC did not match for opdata1 key")
aes = Cipher(algorithms.AES(key), modes.CBC(iv), backend=_backend)
decryptor = aes.decryptor()
decrypted = decryptor.update(cryptext) + decryptor.finalize()
crypto_key, mac_key = decrypted[:key_size], decrypted[key_size:]
return crypto_key, mac_key
def decrypt(self, ct, iv, mac):
ct, iv, mac = bytes(ct, "ascii"), bytes(iv,
"ascii"), bytes(mac, "ascii")
mac = b64decode(mac)
h = HMAC(self.macKey, SHA256(), default_backend())
h.update(ct + iv)
h.verify(mac) #verify MAC
ct, iv = b64decode(ct), b64decode(iv)
decryptor = Cipher(self.cipherAlg, self.mode(iv),
default_backend()).decryptor()
message = decryptor.update(ct) + decryptor.finalize() #decrypt
return message
def hmac_verify(key, data, hash_alg, backend, sig = None):
h = HMAC(
key,
hash_alg,
backend=backend
)
h.update(data)
return h.verify(sig)
def decrypt(self, data, ttl=None):
if not isinstance(data, bytes):
raise TypeError("data must be bytes.")
current_time = int(time.time())
if not data or six.indexbytes(data, 0) != 0x80:
raise InvalidToken
try:
timestamp, = struct.unpack(">Q", data[1:9])
except struct.error:
raise InvalidToken
if ttl is not None:
if timestamp + ttl < current_time:
raise InvalidToken
if current_time + _MAX_CLOCK_SKEW < timestamp:
raise InvalidToken
h = HMAC(self._signing_key, hashes.SHA256(), backend=self._backend)
h.update(data[:-32])
try:
h.verify(data[-32:])
except InvalidSignature:
raise InvalidToken
iv = data[9:25]
ciphertext = data[25:-32]
decryptor = Cipher(
algorithms.AES(self._encryption_key), modes.CBC(iv), self._backend
).decryptor()
plaintext_padded = decryptor.update(ciphertext)
try:
plaintext_padded += decryptor.finalize()
except ValueError:
raise InvalidToken
unpadder = padding.PKCS7(algorithms.AES.block_size).unpadder()
unpadded = unpadder.update(plaintext_padded)
try:
unpadded += unpadder.finalize()
except ValueError:
raise InvalidToken
return unpadded
def _decrypt_cryptography(cls, b_ciphertext, b_crypted_hmac, b_key1, b_key2, b_iv):
# b_key1, b_key2, b_iv = self._gen_key_initctr(b_password, b_salt)
# EXIT EARLY IF DIGEST DOESN'T MATCH
hmac = HMAC(b_key2, hashes.SHA256(), CRYPTOGRAPHY_BACKEND)
hmac.update(b_ciphertext)
try:
hmac.verify(unhexlify(b_crypted_hmac))
except InvalidSignature as e:
raise AnsibleVaultError('HMAC verification failed: %s' % e)
cipher = C_Cipher(algorithms.AES(b_key1), modes.CTR(b_iv), CRYPTOGRAPHY_BACKEND)
decryptor = cipher.decryptor()
unpadder = padding.PKCS7(128).unpadder()
b_plaintext = unpadder.update(
decryptor.update(b_ciphertext) + decryptor.finalize()
) + unpadder.finalize()
return b_plaintext
def test_compress_and_encrypt_no_compression(caplog, mock_open_streams):
orig, new, _ = mock_open_streams
signature = compress_and_encrypt(
orig,
new,
TMP_KEYPAIR,
dict(use_compression=False, use_encryption=True),
)
cipher = Cipher(AES(TMP_KEY), CTR(TMP_NONCE),
backend=default_backend()).decryptor()
hmac = HMAC(TMP_KEY, SHA256(), default_backend())
decrypted = cipher.update(new._fd.getvalue())
hmac.update(new._fd.getvalue())
assert decrypted == orig._fd.getvalue()
assert count_matching_log_lines('read 2 bytes from /orig', caplog) == 4
assert count_matching_log_lines('wrote 2 bytes to /new', caplog) == 4
hmac.verify(signature)
def verify_hmac(key, data, signature):
"""Shortcut for verifying HMAC of a string."""
h = HMAC(
key=key,
algorithm=hashes.SHA256(),
backend=backend
)
h.update(data)
return h.verify(signature)
def _decrypt_cryptography(cls, b_ciphertext, b_crypted_hmac, b_key1, b_key2, b_iv):
# b_key1, b_key2, b_iv = self._gen_key_initctr(b_password, b_salt)
# EXIT EARLY IF DIGEST DOESN'T MATCH
hmac = HMAC(b_key2, hashes.SHA256(), CRYPTOGRAPHY_BACKEND)
hmac.update(b_ciphertext)
try:
hmac.verify(unhexlify(b_crypted_hmac))
except InvalidSignature as e:
raise AnsibleVaultError('HMAC verification failed: %s' % e)
cipher = C_Cipher(algorithms.AES(b_key1), modes.CTR(b_iv), CRYPTOGRAPHY_BACKEND)
decryptor = cipher.decryptor()
unpadder = padding.PKCS7(128).unpadder()
b_plaintext = unpadder.update(
decryptor.update(b_ciphertext) + decryptor.finalize()
) + unpadder.finalize()
return b_plaintext
def decrypt(self, ct, nonce, mac):
ct, nonce, mac = bytes(ct,
"ascii"), bytes(nonce,
"ascii"), bytes(mac, "ascii")
mac = b64decode(mac)
h = HMAC(self.macKey, SHA256(), default_backend())
h.update(ct + nonce)
h.verify(mac) #verify MAC
ct, nonce = b64decode(ct), b64decode(nonce)
decryptor = Cipher(self.cipherAlg(self.key, nonce), None,
default_backend()).decryptor()
message = decryptor.update(ct) + decryptor.finalize() #decrypt
return message
def decrypt(self, data, ttl=None):
if not isinstance(data, bytes):
raise TypeError("data must be bytes.")
current_time = int(time.time())
if not data or six.indexbytes(data, 0) != 0x80:
raise InvalidToken
try:
timestamp, = struct.unpack(">Q", data[1:9])
except struct.error:
raise InvalidToken
if ttl is not None:
if timestamp + ttl < current_time:
raise InvalidToken
if current_time + _MAX_CLOCK_SKEW < timestamp:
raise InvalidToken
h = HMAC(self._signing_key, hashes.SHA256(), backend=self._backend)
h.update(data[:-32])
try:
h.verify(data[-32:])
except InvalidSignature:
raise InvalidToken
iv = data[9:25]
ciphertext = data[25:-32]
decryptor = Cipher(algorithms.AES(self._encryption_key), modes.CBC(iv),
self._backend).decryptor()
plaintext_padded = decryptor.update(ciphertext)
try:
plaintext_padded += decryptor.finalize()
except ValueError:
raise InvalidToken
unpadder = padding.PKCS7(algorithms.AES.block_size).unpadder()
unpadded = unpadder.update(plaintext_padded)
try:
unpadded += unpadder.finalize()
except ValueError:
raise InvalidToken
return unpadded
def dec(self, byts):
'''
Decode an envelope dict and decrypt the given bytes.
Args:
byts (bytes): Bytes to decrypt.
Returns:
bytes: Decrypted message.
'''
envl = s_msgpack.un(byts)
macr = HMAC(self.skey, hashes.SHA256(), backend=self.bend)
iv = envl.get('iv', b'')
hmac = envl.get('hmac', b'')
data = envl.get('data', b'')
macr.update(iv + data)
try:
macr.verify(hmac)
except InvalidSignature as e:
logger.warning('Error in macr.verify: [%s]', str(e))
return None
mode = modes.CBC(iv)
algo = algorithms.AES(self.ekey)
decr = Cipher(algo, mode, self.bend).decryptor()
# decrypt the remaining bytes
byts = decr.update(data)
byts += decr.finalize()
# unpad the decrypted bytes
padr = padding.PKCS7(self.bsize).unpadder()
byts = padr.update(byts)
byts += padr.finalize()
return byts
def _decrypt_cryptography(b_ciphertext, b_crypted_hmac, b_key1, b_key2,
b_iv):
# EXIT EARLY IF DIGEST DOESN'T MATCH
hmac = HMAC(b_key2, hashes.SHA256(), CRYPTOGRAPHY_BACKEND)
hmac.update(b_ciphertext)
try:
hmac.verify(unhexlify(b_crypted_hmac))
except InvalidSignature:
return None
cipher = C_Cipher(algorithms.AES(b_key1), modes.CTR(b_iv),
CRYPTOGRAPHY_BACKEND)
decryptor = cipher.decryptor()
unpadder = padding.PKCS7(128).unpadder()
b_plaintext = unpadder.update(
decryptor.update(b_ciphertext) +
decryptor.finalize()) + unpadder.finalize()
return b_plaintext
def decrypt(self, token, associated_data=b"", ttl=None):
if not isinstance(token, bytes):
raise TypeError("token must be bytes.")
current_time = int(time.time())
try:
data = base64.urlsafe_b64decode(token)
except (TypeError, binascii.Error):
raise InvalidToken
if not data or (six.indexbytes(data, 0) != 0x81):
raise InvalidToken
h = HMAC(self._signing_key, hashes.SHA256(), backend=self._backend)
h.update(data[:-32] + associated_data)
try:
h.verify(data[-32:])
except InvalidSignature:
raise InvalidToken
iv = data[1:17]
ciphertext = data[17:-32]
decryptor = Cipher(
algorithms.AES(self._encryption_key), modes.CBC(iv), self._backend
).decryptor()
plaintext_padded = decryptor.update(ciphertext)
try:
plaintext_padded += decryptor.finalize()
except ValueError:
raise InvalidToken
unpadder = padding.PKCS7(algorithms.AES.block_size).unpadder()
unpadded = unpadder.update(plaintext_padded)
try:
unpadded += unpadder.finalize()
except ValueError:
raise InvalidToken
return unpadded
def decrypt(self, token, associated_data=b"", ttl=None):
if not isinstance(token, bytes):
raise TypeError("token must be bytes.")
current_time = int(time.time())
try:
data = base64.urlsafe_b64decode(token)
except (TypeError, binascii.Error):
raise InvalidToken
if not data or (six.indexbytes(data, 0) != 0x81):
raise InvalidToken
h = HMAC(self._signing_key, hashes.SHA256(), backend=self._backend)
h.update(data[:-32] + associated_data)
try:
h.verify(data[-32:])
except InvalidSignature:
raise InvalidToken
iv = data[1:17]
ciphertext = data[17:-32]
decryptor = Cipher(algorithms.AES(self._encryption_key), modes.CBC(iv),
self._backend).decryptor()
plaintext_padded = decryptor.update(ciphertext)
try:
plaintext_padded += decryptor.finalize()
except ValueError:
raise InvalidToken
unpadder = padding.PKCS7(algorithms.AES.block_size).unpadder()
unpadded = unpadder.update(plaintext_padded)
try:
unpadded += unpadder.finalize()
except ValueError:
raise InvalidToken
return unpadded
def opdata1_decrypt_item(data, key, hmac_key, aes_size=C_AES_SIZE, ignore_hmac=False):
key_size = KEY_SIZE[aes_size]
assert len(key) == key_size
assert len(data) >= OPDATA1_MINIMUM_SIZE
plaintext_length, iv, cryptext, expected_hmac, hmac_d_data = opdata1_unpack(data)
if not ignore_hmac:
verifier = HMAC(hmac_key, SHA256(), backend=_backend)
verifier.update(hmac_d_data)
if len(verifier.copy().finalize()) != len(expected_hmac):
raise ValueError("Got unexpected HMAC length (expected %d bytes, got %d bytes)" % (
len(expected_hmac),
len(got_hmac)
))
try:
verifier.verify(expected_hmac)
except InvalidSignature:
raise ValueError("HMAC did not match for opdata1 record")
aes = Cipher(algorithms.AES(key), modes.CBC(iv), backend=_backend)
decryptor = aes.decryptor()
decrypted = decryptor.update(cryptext) + decryptor.finalize()
unpadded = padding.ab_unpad(decrypted, plaintext_length)
return unpadded
def decrypt(self, token):
if not isinstance(token, bytes):
raise TypeError("token must be bytes")
if not token or six.indexbytes(token, 0) != 0x80:
raise InvalidToken
hmac = token[-32:]
h = HMAC(self.mac_key, hashes.SHA256(), backend=self.backend)
h.update(token[:-32])
try:
h.verify(hmac)
except InvalidSignature:
raise InvalidToken
iv = token[1:17]
ciphertext = token[17:-32]
decryptor = Cipher(algorithms.AES(self.aes_key), modes.CBC(iv),
self.backend).decryptor()
plaintext_padded = decryptor.update(ciphertext)
try:
plaintext_padded += decryptor.finalize()
except ValueError:
raise InvalidToken
plaintext = self.remove_padding(plaintext_padded,
algorithms.AES.block_size)
try:
data_id, = struct.unpack(config.FORMAT_CHAR, plaintext[:8])
except struct.error:
raise InvalidToken
if data_id == config.DUMMY_ID:
raise DummyFileFound
data = plaintext[8:]
return data_id, data
def decrypt(self, token):
if not isinstance(token, bytes):
raise TypeError("token must be bytes")
if not token or six.indexbytes(token, 0) != 0x80:
raise InvalidToken
hmac = token[-32:]
h = HMAC(self.mac_key, hashes.SHA256(), backend=self.backend)
h.update(token[:-32])
try:
h.verify(hmac)
except InvalidSignature:
raise InvalidToken
iv = token[1:17]
ciphertext = token[17:-32]
decryptor = Cipher(algorithms.AES(self.aes_key), modes.CBC(iv), self.backend).decryptor()
plaintext_padded = decryptor.update(ciphertext)
try:
plaintext_padded += decryptor.finalize()
except ValueError:
raise InvalidToken
plaintext = self.remove_padding(plaintext_padded, algorithms.AES.block_size)
try:
data_id, = struct.unpack(config.FORMAT_CHAR, plaintext[:8])
except struct.error:
raise InvalidToken
if data_id == config.DUMMY_ID:
raise DummyFileFound
data = plaintext[8:]
return data_id, data
def decrypt(self, token, ttl=None, adata = ""):
if not isinstance(token, bytes):
raise TypeError("token must be bytes.")
try:
data = base64.urlsafe_b64decode(token)
except (TypeError, binascii.Error):
raise InvalidToken
if data == 0x82 or six.indexbytes(data, 0) == 0x82:
# print("82 version\n")
try:
salt = data[1:17]
except ValueError:
raise InvalidToken
# print("salt == " + str(len(salt)), salt)
# is this producing same signing and encrypt key? YES!
signing_key, encryption_key = self.gen_encrypt_key(salt, self._password)
# print("signing_key == " + str(len(signing_key)), signing_key)
# print("encryption_key == " + str(len(encryption_key)), encryption_key)
############ VERIFYING adata
# print("data = " + str(len(data)), data)
h = HMAC(signing_key, hashes.SHA256(), backend=self._backend)
basic_parts = data[:-32]
basic_adata = basic_parts + base64.urlsafe_b64decode(base64.urlsafe_b64encode(adata))
# print("==================", base64.urlsafe_b64decode(base64.urlsafe_b64encode(adata)))
h.update(basic_adata)
# print("basic_parts_len = " + str(len(basic_parts)), basic_parts)
# print("basic_adata = " + str(len(basic_adata)), basic_adata)
# print("adata = " , len(adata), adata)
try:
h.verify(data[-32:])
except InvalidSignature:
raise InvalidToken
################ signature stuff from fernet.py
# h = HMAC(self._signing_key, hashes.SHA256(), backend=self._backend)
# h.update(data[:-32]) # get everything from data except for last 32 bytes
# # print(h.update(data[:-32]))
# try:
# # verifying signature with the last 32 bytes
# h.verify(data[-32:])
# except InvalidSignature:
# raise InvalidToken
################ END-OF signature stuff from fernet.py
# TODO: get associated data
# check for correct associated data
# iv = data[9:25]
# find out associated data in data
# try satement, if adata_to_get = adata
ciphertext = data[17:-32]
decryptor = Cipher(
algorithms.AES(encryption_key), modes.CBC("0"*16), self._backend
).decryptor()
plaintext_padded = decryptor.update(ciphertext)
try:
plaintext_padded += decryptor.finalize()
except ValueError:
raise InvalidToken
unpadder = padding.PKCS7(algorithms.AES.block_size).unpadder()
unpadded = unpadder.update(plaintext_padded)
try:
unpadded += unpadder.finalize()
except ValueError:
raise InvalidToken
return unpadded
else:
raise InvalidToken
def decrypt(self, token, ttl=None, adata=""):
if not isinstance(token, bytes):
raise TypeError("token must be bytes.")
# print("token = ", token)
try:
data = base64.urlsafe_b64decode(token)
except (TypeError, binascii.Error):
raise InvalidToken
# print("data = ", data)
if not data or six.indexbytes(data, 0) == 0x80:
print("80 version\n")
# TODO: if 80:
try:
msg = self._f.decrypt(token, ttl)
return msg
except:
raise InvalidToken
elif not data or six.indexbytes(data, 0) == 0x81:
# print("81 version\n")
############ VERIFYING adata
# print("data = " + str(len(data)), data)
h = HMAC(self._signing_key, hashes.SHA256(), backend=self._backend)
basic_parts = data[:-32]
basic_adata = basic_parts + bytes(adata)
# print("==================", base64.urlsafe_b64decode(base64.urlsafe_b64encode(adata)))
h.update(basic_adata)
# print("basic_parts_len = " + str(len(basic_parts)), basic_parts)
# print("basic_adata = " + str(len(basic_adata)), basic_adata)
# print("adata = " , len(adata), adata)
try:
h.verify(data[-32:])
except InvalidSignature:
raise InvalidToken
################ signature stuff from fernet.py
# h = HMAC(self._signing_key, hashes.SHA256(), backend=self._backend)
# h.update(data[:-32]) # get everything from data except for last 32 bytes
# # print(h.update(data[:-32]))
# try:
# # verifying signature with the last 32 bytes
# h.verify(data[-32:])
# except InvalidSignature:
# raise InvalidToken
################ END-OF signature stuff from fernet.py
# iv = data[9:25]
iv = data[1:17]
# print("iv == " + str(len(iv)), iv)
# find out associated data in data
# try satement, if adata_to_get = adata
ciphertext = data[17:-32]
decryptor = Cipher(
algorithms.AES(self._encryption_key), modes.CBC(iv), self._backend
).decryptor()
plaintext_padded = decryptor.update(ciphertext)
try:
plaintext_padded += decryptor.finalize()
except ValueError:
raise InvalidToken
unpadder = padding.PKCS7(algorithms.AES.block_size).unpadder()
unpadded = unpadder.update(plaintext_padded)
try:
unpadded += unpadder.finalize()
except ValueError:
raise InvalidToken
return unpadded
else:
raise InvalidToken
