Add Ack check in group msg

src/transport/SessionManager.cpp

@@ -486,21 +486,25 @@ void SessionManager::SecureGroupMessageDispatch(const PacketHeader & packetHeade
         ExitNow(err = CHIP_NO_ERROR);
     }
 
+    // Group Messages should never send an Ack
+    if (payloadHeader.NeedsAck())
+    {
+        ChipLogError(Inet, "Invalid condition found in protocol header");
+        ExitNow(err = CHIP_ERROR_INCORRECT_STATE);
+    }
+
     // TODO: Handle Group message counter here spec 4.7.3
     // spec 4.5.1.2 for msg counter
 
-    if (isDuplicate == SessionManagerDelegate::DuplicateMessage::Yes && !payloadHeader.NeedsAck())
+    if (isDuplicate == SessionManagerDelegate::DuplicateMessage::Yes)
     {
         ChipLogDetail(Inet,
                       "Received a duplicate message with MessageCounter:" ChipLogFormatMessageCounter
                       " on exchange " ChipLogFormatExchangeId,
                       packetHeader.GetMessageCounter(), ChipLogValueExchangeIdFromReceivedHeader(payloadHeader));
-        if (!payloadHeader.NeedsAck())
-        {
-            // If it's a duplicate message, but doesn't require an ack, let's drop it right here to save CPU
-            // cycles on further message processing.
-            ExitNow(err = CHIP_NO_ERROR);
-        }
+
+        // If it's a duplicate message, let's drop it right here to save CPU cycles
+        ExitNow(err = CHIP_NO_ERROR);
     }
 
     // TODO: Commit Group Message Counter