Display Identity Key & Pairing Date: necessary to calculate the EID for presence detection

[HarryR]

This is super cool, just integrated FMDN BLE presence detection in an app, but I needed to extract the pairing date and identity key to do so. After that it was fairly straightforward to observe the packets, calculate and verify the EID etc. from the advertised frames.

diff --git a/NovaApi/ExecuteAction/LocateTracker/decrypt_locations.py b/NovaApi/ExecuteAction/LocateTracker/decrypt_locations.py
index c0e7033..05df49c 100644
--- a/NovaApi/ExecuteAction/LocateTracker/decrypt_locations.py
+++ b/NovaApi/ExecuteAction/LocateTracker/decrypt_locations.py
@@ -72,6 +72,13 @@ def decrypt_location_response_locations(device_update_protobuf):
     device_registration = device_update_protobuf.deviceMetadata.information.deviceRegistration
 
     identity_key = retrieve_identity_key(device_registration)
+    pair_date = device_registration.pairDate
+    print(f"\n{'='*60}")
+    print(f"IDENTITY KEY:")
+    print(f"{identity_key.hex()}")
+    print(f"PAIR DATE: {pair_date}")
+    print(f"{'='*60}\n")
     locations_proto = device_update_protobuf.deviceMetadata.information.locationInformation.reports.recentLocationAndNetworkLocations
     is_mcu = is_mcu_tracker(device_registration)

Here is example code: https://gist.github.com/HarryR/93c07f679370849e5e32fe7e12aa7610

[HarryR]

Have released the project which uses this, FYI: https://github.com/HarryR/nomadcam