Initial commit

decrypt_otpauth.py

@@ -0,0 +1,187 @@
+import click
+import getpass
+
+from enum import Enum
+
+from Crypto.Cipher import AES
+import hashlib
+
+from bpylist import archiver
+from bpylist.archive_types import uid
+
+class Type(Enum):
+	Unknown = 0
+	HOTP = 1
+	TOTP = 2
+
+class Algorithm(Enum):
+	Unknown = 0
+	SHA1 = 1 # Used in case of Unknown
+	SHA256 = 2
+	SHA512 = 3
+	MD5 = 4
+
+class MutableString:
+
+    def decode_archive(archive):
+        return archive.decode('NS.string')
+
+class MutableData:
+
+    def decode_archive(archive):
+        return bytes(archive.decode('NS.data'))
+
+class OTPFolder:
+    name = None
+    accounts = None
+
+    def __init__(self, name, accounts):
+        self.name = name
+        self.accounts = accounts
+
+    def __repr__(self):
+        return f'<OTPFolder: {self.name}, {self.accounts}>'
+
+    def decode_archive(archive):
+        name = archive.decode('name')
+        accounts = archive.decode('accounts')
+        return OTPFolder(name, accounts)
+
+class OTPAccount:
+    label = None
+    issue = None
+    secret = None
+    type = None
+    algorithm = None
+    digits = None
+    counter = None
+    period = None
+    refDate = None
+
+    def __init__(self, label, issuer, secret, type, algorithm, digits, counter, period, refDate):
+        self.label = label
+        self.issuer = issuer
+        self.secret = secret
+        self.type = type
+        self.algorithm = algorithm
+        self.digits = digits
+        self.counter = counter
+        self.period = period
+        self.refDate = refDate
+
+    def __repr__(self):
+        return f'<OTPAccount: {self.label} ({self.issuer}), Secret: 0x{self.secret.hex()}, Type: {self.type}, Algorithm: {self.algorithm}, Digits: {self.digits}, Counter: {self.counter}, Period: {self.period}, Reference Date: {self.refDate}>'
+
+    def decode_archive(archive):
+        label = archive.decode("label")
+        issuer = archive.decode("issuer")
+        secret = bytes(archive.decode("secret"))
+        type = Type(archive.decode("type"))
+        algorithm = Algorithm(archive.decode("algorithm"))
+        digits = archive.decode("digits")
+        counter = archive.decode("counter")
+        period = archive.decode("period")
+        refDate = archive.decode("refDate")
+        return OTPAccount(label, issuer, secret, type, algorithm, digits, counter, period, refDate)
+
+archiver.update_class_map({'NSMutableData': MutableData})
+archiver.update_class_map({'NSMutableString': MutableString})
+archiver.update_class_map({'ACOTPFolder': OTPFolder})
+archiver.update_class_map({'ACOTPAccount': OTPAccount})
+
+class DangerousUnarchive(archiver.Unarchive):
+
+    def decode_object(self, index):
+        if index == 0:
+            return None
+
+        obj = self.unpacked_uids.get(index)
+
+        if obj is not None:
+            return obj
+
+        raw_obj = self.objects[index]
+
+        # if obj is a (semi-)primitive type (e.g. str)
+        if not isinstance(raw_obj, dict):
+            return raw_obj
+
+        class_uid = raw_obj.get('$class')
+        if not isinstance(class_uid, uid):
+            raise archiver.MissingClassUID(raw_obj)
+
+        klass = self.class_for_uid(class_uid)
+        obj = klass.decode_archive(archiver.ArchivedObject(raw_obj, self))
+
+        self.unpacked_uids[index] = obj
+        return obj
+
+# @click.command()
+# @click.option('--encrypted-otpauth-account',
+#               help="path to your encrypted OTP Auth account (.otpauth)",
+#               required=True,
+#               type=click.File('rb'))
+# def main(encrypted_otpauth_account):
+#     # Get password from user
+#     password = getpass.getpass(f'Password for export file {encrypted_otpauth_account.name}: ')
+
+#     # Get IV and key for wrapping archive
+#     iv = bytes(16)
+#     key = hashlib.sha256('OTPAuth'.encode('utf-8')).digest()
+
+#     # Decrypt wrapping archive
+#     data = AES.new(key, AES.MODE_CBC, iv).decrypt(encrypted_otpauth_account.read())
+#     data = data[:-data[-1]]
+
+#     # Decode wrapping archive
+#     archive = DangerousUnarchive(data).top_object()
+
+#     # Get IV and key for actual archive
+#     iv = hashlib.sha1(archive['IV']).digest()[:16]
+#     salt = archive['Salt']
+#     key = hashlib.sha256((salt + '-' + password).encode('utf-8')).digest()
+    
+#     # Decrypt actual archive
+#     data = AES.new(key, AES.MODE_CBC, iv).decrypt(archive['Data'])
+#     data = data[:-data[-1]]
+
+#     # Decode actual archive
+#     archive = DangerousUnarchive(data).top_object()
+#     print(archive)
+
+@click.command()
+@click.option('--encrypted-otpauth-backup',
+              help="path to your encrypted OTP Auth backup (.otpauthdb)",
+              required=True,
+              type=click.File('rb'))
+def main(encrypted_otpauth_backup):
+    # Get password from user
+    password = getpass.getpass(f'Password for export file {encrypted_otpauth_backup.name}: ')
+
+    # Get IV and key for wrapping archive
+    iv = bytes(16)
+    key = hashlib.sha256('Authenticator'.encode('utf-8')).digest()
+
+    # Decrypt wrapping archive
+    data = AES.new(key, AES.MODE_CBC, iv).decrypt(encrypted_otpauth_backup.read())
+    data = data[:-data[-1]]
+
+    # Decode wrapping archive
+    archive = DangerousUnarchive(data).top_object()
+
+    # Get IV and key for actual archive
+    iv = hashlib.sha1(archive['IV'].encode('utf-8')).digest()[:16]
+    salt = archive['Salt']
+    key = hashlib.sha256((salt + '-' + password).encode('utf-8')).digest()
+    
+    # Decrypt actual archive
+    data = AES.new(key, AES.MODE_CBC, iv).decrypt(archive['WrappedData'])
+    data = data[:-data[-1]]
+
+    # Decode actual archive
+    archive = DangerousUnarchive(data).top_object()
+    print(archive)
+
+
+if __name__ == '__main__':
+    main()