From d1a461a2b3be0f94211916cf2bb9e91c4dfbd6bf Mon Sep 17 00:00:00 2001 From: Mark Qvist Date: Wed, 8 Jun 2022 12:21:50 +0200 Subject: [PATCH] Added multi-backend abstraction for AES-128 CBC primitive --- RNS/Cryptography/AES.py | 55 ++++++++++++++++++++++++++++++++++++++ RNS/Cryptography/Fernet.py | 38 +++++++++++++++++++++----- RNS/Cryptography/HKDF.py | 22 +++++++++++++++ RNS/Cryptography/PKCS7.py | 22 +++++++++++++++ 4 files changed, 131 insertions(+), 6 deletions(-) create mode 100644 RNS/Cryptography/AES.py diff --git a/RNS/Cryptography/AES.py b/RNS/Cryptography/AES.py new file mode 100644 index 0000000..88d35ce --- /dev/null +++ b/RNS/Cryptography/AES.py @@ -0,0 +1,55 @@ +# MIT License +# +# Copyright (c) 2022 Mark Qvist / unsigned.io +# +# Permission is hereby granted, free of charge, to any person obtaining a copy +# of this software and associated documentation files (the "Software"), to deal +# in the Software without restriction, including without limitation the rights +# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell +# copies of the Software, and to permit persons to whom the Software is +# furnished to do so, subject to the following conditions: +# +# The above copyright notice and this permission notice shall be included in all +# copies or substantial portions of the Software. +# +# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR +# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, +# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE +# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER +# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, +# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE +# SOFTWARE. + +PROVIDER_INTERNAL = 0x01 +PROVIDER_PYCA = 0x02 + +provider = PROVIDER_PYCA + +if provider == PROVIDER_INTERNAL: + pass +elif provider == PROVIDER_PYCA: + from cryptography.hazmat.primitives.ciphers import Cipher, algorithms, modes + + +class AES_128_CBC: + + @staticmethod + def encrypt(plaintext, key, iv): + if provider == PROVIDER_INTERNAL: + pass + elif provider == PROVIDER_PYCA: + cipher = Cipher(algorithms.AES(key), modes.CBC(iv)) + encryptor = cipher.encryptor() + ciphertext = encryptor.update(plaintext) + encryptor.finalize() + return ciphertext + + @staticmethod + def decrypt(ciphertext, key, iv): + if provider == PROVIDER_INTERNAL: + pass + elif provider == PROVIDER_PYCA: + cipher = Cipher(algorithms.AES(key), modes.CBC(iv)) + decryptor = cipher.decryptor() + plaintext = decryptor.update(ciphertext) + decryptor.finalize() + return plaintext + diff --git a/RNS/Cryptography/Fernet.py b/RNS/Cryptography/Fernet.py index 6254140..790747b 100644 --- a/RNS/Cryptography/Fernet.py +++ b/RNS/Cryptography/Fernet.py @@ -1,3 +1,26 @@ +# MIT License +# +# Copyright (c) 2022 Mark Qvist / unsigned.io +# +# Permission is hereby granted, free of charge, to any person obtaining a copy +# of this software and associated documentation files (the "Software"), to deal +# in the Software without restriction, including without limitation the rights +# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell +# copies of the Software, and to permit persons to whom the Software is +# furnished to do so, subject to the following conditions: +# +# The above copyright notice and this permission notice shall be included in all +# copies or substantial portions of the Software. +# +# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR +# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, +# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE +# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER +# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, +# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE +# SOFTWARE. + +import os import time from RNS.Cryptography import HMAC @@ -10,9 +33,12 @@ class Fernet(): def generate_key(): return os.urandom(32) - def __init__(key = None): - if not len(key) != 32: - raise ValueError("Fernet key must be 256 bits (32 bytes) long") + def __init__(self, key = None): + if key == None: + raise ValueError("Fernet key cannot be None") + + if len(key) != 32: + raise ValueError("Fernet key must be 32 bytes, not "+str(len(key))) self._signing_key = key[:16] self._encryption_key = key[16:] @@ -33,7 +59,7 @@ class Fernet(): def encrypt(self, data = None): iv = os.urandom(16) - current_time = time.time() + current_time = int(time.time()) if not isinstance(data, bytes): raise TypeError("Fernet token plaintext input must be bytes") @@ -57,13 +83,13 @@ class Fernet(): raise ValueError("Fernet token HMAC was invalid") iv = token[9:25] - ciphertext = [25:-32] + ciphertext = token[25:-32] try: plaintext = PKCS7.unpad( AES_128_CBC.decrypt( - self._encryption_key, ciphertext, + self._encryption_key, iv, ) ) diff --git a/RNS/Cryptography/HKDF.py b/RNS/Cryptography/HKDF.py index 13b3186..111123a 100644 --- a/RNS/Cryptography/HKDF.py +++ b/RNS/Cryptography/HKDF.py @@ -1,3 +1,25 @@ +# MIT License +# +# Copyright (c) 2022 Mark Qvist / unsigned.io +# +# Permission is hereby granted, free of charge, to any person obtaining a copy +# of this software and associated documentation files (the "Software"), to deal +# in the Software without restriction, including without limitation the rights +# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell +# copies of the Software, and to permit persons to whom the Software is +# furnished to do so, subject to the following conditions: +# +# The above copyright notice and this permission notice shall be included in all +# copies or substantial portions of the Software. +# +# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR +# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, +# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE +# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER +# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, +# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE +# SOFTWARE. + import hashlib from math import ceil from RNS.Cryptography import HMAC diff --git a/RNS/Cryptography/PKCS7.py b/RNS/Cryptography/PKCS7.py index acffa63..aa3bef0 100644 --- a/RNS/Cryptography/PKCS7.py +++ b/RNS/Cryptography/PKCS7.py @@ -1,3 +1,25 @@ +# MIT License +# +# Copyright (c) 2022 Mark Qvist / unsigned.io +# +# Permission is hereby granted, free of charge, to any person obtaining a copy +# of this software and associated documentation files (the "Software"), to deal +# in the Software without restriction, including without limitation the rights +# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell +# copies of the Software, and to permit persons to whom the Software is +# furnished to do so, subject to the following conditions: +# +# The above copyright notice and this permission notice shall be included in all +# copies or substantial portions of the Software. +# +# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR +# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, +# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE +# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER +# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, +# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE +# SOFTWARE. + class PKCS7: BLOCKSIZE = 16