commit 5ab96033f09f7c3c711910ac6fe12c6dbf00f612 Author: Patrick O'Doherty <p@trickod.com> Date: Sat Feb 25 17:47:49 2017 -0800 Replace pycrypto in hidden_service_descriptor Deprecate all use of pycrypto in hidden_service_descriptor module and replace with the cryptography library. --- stem/descriptor/hidden_service_descriptor.py | 29 +++++++++++++--------------- 1 file changed, 13 insertions(+), 16 deletions(-) diff --git a/stem/descriptor/hidden_service_descriptor.py b/stem/descriptor/hidden_service_descriptor.py index 97cd19e..30754b8 100644 --- a/stem/descriptor/hidden_service_descriptor.py +++ b/stem/descriptor/hidden_service_descriptor.py @@ -296,9 +296,8 @@ class HiddenServiceDescriptor(Descriptor): @staticmethod def _decrypt_basic_auth(content, authentication_cookie): - from Crypto.Cipher import AES - from Crypto.Util import Counter - from Crypto.Util.number import bytes_to_long + from cryptography.hazmat.primitives.ciphers import Cipher, algorithms, modes + from cryptography.hazmat.backends import default_backend try: client_blocks = int(binascii.hexlify(content[1:2]), 16) @@ -322,15 +321,15 @@ class HiddenServiceDescriptor(Descriptor): # try decrypting the session key - counter = Counter.new(128, initial_value = 0) - cipher = AES.new(authentication_cookie, AES.MODE_CTR, counter = counter) - session_key = cipher.decrypt(encrypted_session_key) + cipher = Cipher(algorithms.AES(authentication_cookie), modes.CTR('\x00' * len(iv)), default_backend()) + decryptor = cipher.decryptor() + session_key = decryptor.update(encrypted_session_key) + decryptor.finalize() # attempt to decrypt the intro points with the session key - counter = Counter.new(128, initial_value = bytes_to_long(iv)) - cipher = AES.new(session_key, AES.MODE_CTR, counter = counter) - decrypted = cipher.decrypt(encrypted) + cipher = Cipher(algorithms.AES(session_key), modes.CTR(iv), default_backend()) + decryptor = cipher.decryptor() + decrypted = decryptor.update(encrypted) + decryptor.finalize() # check if the decryption looks correct @@ -341,17 +340,15 @@ class HiddenServiceDescriptor(Descriptor): @staticmethod def _decrypt_stealth_auth(content, authentication_cookie): - from Crypto.Cipher import AES - from Crypto.Util import Counter - from Crypto.Util.number import bytes_to_long + from cryptography.hazmat.primitives.ciphers import Cipher, algorithms, modes + from cryptography.hazmat.backends import default_backend # byte 1 = authentication type, 2-17 = input vector, 18 on = encrypted content - iv, encrypted = content[1:17], content[17:] - counter = Counter.new(128, initial_value = bytes_to_long(iv)) - cipher = AES.new(authentication_cookie, AES.MODE_CTR, counter = counter) + cipher = Cipher(algorithms.AES(authentication_cookie), modes.CTR(iv), default_backend()) + decryptor = cipher.decryptor() - return cipher.decrypt(encrypted) + return decryptor.update(encrypted) + decryptor.finalize() @staticmethod def _parse_introduction_points(content):