Added destination ratchet ID getter to API

RNS/Identity.py

@@ -213,7 +213,7 @@ class Identity:
         Get a SHA-256 hash of passed data.
 
         :param data: Data to be hashed as *bytes*.
-        :returns: SHA-256 hash as *bytes*
+        :returns: SHA-256 hash as *bytes*.
         """
         return RNS.Cryptography.sha256(data)
 
@@ -223,7 +223,7 @@ class Identity:
         Get a truncated SHA-256 hash of passed data.
 
         :param data: Data to be hashed as *bytes*.
-        :returns: Truncated SHA-256 hash as *bytes*
+        :returns: Truncated SHA-256 hash as *bytes*.
         """
         return Identity.full_hash(data)[:(Identity.TRUNCATED_HASHLENGTH//8)]
 
@@ -233,10 +233,24 @@ class Identity:
         Get a random SHA-256 hash.
 
         :param data: Data to be hashed as *bytes*.
-        :returns: Truncated SHA-256 hash of random data as *bytes*
+        :returns: Truncated SHA-256 hash of random data as *bytes*.
         """
         return Identity.truncated_hash(os.urandom(Identity.TRUNCATED_HASHLENGTH//8))
 
+    @staticmethod
+    def current_ratchet_id(destination_hash):
+        """
+        Get the ID of the currently used ratchet key for a given destination hash
+
+        :param destination_hash: A destination hash as *bytes*.
+        :returns: A ratchet ID as *bytes* or *None*.
+        """
+        ratchet = Identity.get_ratchet(destination_hash)
+        if ratchet == None:
+            return None
+        else:
+            return Identity.truncated_hash(ratchet)
+
     @staticmethod
     def _ratchet_public_bytes(ratchet):
         return X25519PrivateKey.from_private_bytes(ratchet).public_key().public_bytes()

RNS/Transport.py

@@ -1709,6 +1709,7 @@ class Transport:
                                 except Exception as e:
                                     RNS.log("Error while processing external announce callback.", RNS.LOG_ERROR)
                                     RNS.log("The contained exception was: "+str(e), RNS.LOG_ERROR)
+                                    RNS.trace_exception(e)
 
             # Handling for link requests to local destinations
             elif packet.packet_type == RNS.Packet.LINKREQUEST: