Catch exceptions in CAN signal packets

polybassa · polybassa · commit ac5e7c598a69 · 2020-12-27T17:27:31.000+01:00
diff --git a/scapy/layers/can.py b/scapy/layers/can.py
@@ -132,13 +132,21 @@ def __init__(self, name, default, start, size, scaling=1, unit="",
     @staticmethod
     def _msb_lookup(start):
         # type: (int) -> int
-        return SignalField._lookup_table.index(start)
+        try:
+            return SignalField._lookup_table.index(start)
+        except ValueError:
+            raise Scapy_Exception("Only 64 bits for all SignalFields "
+                                  "are supported")
 
     @staticmethod
     def _lsb_lookup(start, size):
         # type: (int, int) -> int
-        return SignalField._lookup_table[SignalField._msb_lookup(start) +
-                                         size - 1]
+        try:
+            return SignalField._lookup_table[SignalField._msb_lookup(start) +
+                                             size - 1]
+        except IndexError:
+            raise Scapy_Exception("Only 64 bits for all SignalFields "
+                                  "are supported")
 
     @staticmethod
     def _convert_to_unsigned(number, bit_length):
