Support AirDrop authentication by using extracted secrets (fixes #53)

README.md

@@ -4,8 +4,8 @@
 [![Language grade](https://img.shields.io/lgtm/grade/python/github/seemoo-lab/opendrop?label=code%20quality)](https://lgtm.com/projects/g/seemoo-lab/opendrop/context:python)
 
 *OpenDrop* is a command-line tool that allows sharing files between devices directly over Wi-Fi. Its unique feature is that it is protocol-compatible with Apple AirDrop which allows to share files with Apple devices running iOS and macOS. 
-Currently (and probably also for the foreseeable future), OpenDrop only supports sending to Apple devices that are discoverable by *everybody* as the default *contacts only* mode requires [Apple-signed certificates](https://www.apple.com/certificateauthority/pdf/Apple_AAI_CPS_v6.1.pdf).
-
+~~Currently (and probably also for the foreseeable future), OpenDrop only supports sending to Apple devices that are discoverable by *everybody* as the default *contacts only* mode requires [Apple-signed certificates](https://www.apple.com/certificateauthority/pdf/Apple_AAI_CPS_v6.1.pdf).~~
+We support contacts-only devices by using extracted AirDrop credentials (keys and certificates) from macOS via our [keychain extractor](https://github.com/seemoo-lab/airdrop-keychain-extractor).
 
 ## Disclaimer
 

opendrop/config.py

@@ -120,8 +120,14 @@ class AirDropConfig:
             logger.info("Key file or certificate does not exist")
             self.create_default_key()
 
-        # TODO extract record data from a sample exchange
+        self.record_file = os.path.join(self.key_dir, "validation_record.cms")
         self.record_data = None
+        if os.path.exists(self.record_file):
+            logger.debug("Using provided Apple ID Validation Record")
+            with open(self.record_file, "rb") as f:
+                self.record_data = f.read()
+        else:
+            logger.debug("No Apple ID Validation Record found")
 
     def create_default_key(self):
         logger.info("Create new self-signed certificate in {}".format(self.key_dir))