Make Dot11EltVendorSpecific packet extensible

scapy/layers/dot11.py

@@ -1439,22 +1439,25 @@ class Dot11EltVendorSpecific(Dot11Elt):
     def dispatch_hook(cls, _pkt=None, *args, **kargs):
         if _pkt:
             oui = struct.unpack("!I", b"\x00" + _pkt[2:5])[0]
-            if oui == 0x0050f2:  # Microsoft
-                type_ = orb(_pkt[5])
-                if type_ == 0x01:
-                    # MS WPA IE
-                    return Dot11EltMicrosoftWPA
-                elif type_ == 0x02:
-                    # MS WME IE TODO
-                    # return Dot11EltMicrosoftWME
-                    pass
-                elif type_ == 0x04:
-                    # MS WPS IE TODO
-                    # return Dot11EltWPS
-                    pass
-                return Dot11EltVendorSpecific
+            ouicls = cls.registered_ouis.get(oui, cls)
+            if ouicls.dispatch_hook != cls.dispatch_hook:
+                # Sub-classes can have their own dispatch_hook
+                return ouicls.dispatch_hook(_pkt=_pkt, *args, **kargs)
+            cls = ouicls
         return cls
 
+    registered_ouis = {}
+
+    @classmethod
+    def register_variant(cls):  # XXX: We do not accept id, but our super-class does
+        oui = cls.oui.default
+        if not oui:
+            # This is Dot11EltVendorSpecific, register it in the super-class.
+            super().register_variant()
+        elif oui not in cls.registered_ouis:
+            # Sub-Vendor (e.g. Dot11EltMicrosoftWPA)
+            cls.registered_ouis[oui] = cls
+
 
 class Dot11EltMicrosoftWPA(Dot11EltVendorSpecific):
     name = "802.11 Microsoft WPA"
@@ -1467,6 +1470,24 @@ class Dot11EltMicrosoftWPA(Dot11EltVendorSpecific):
         XByteField("type", 0x01)
     ] + Dot11EltRSN.fields_desc[2:8]
 
+    @classmethod
+    def dispatch_hook(cls, _pkt=None, *args, **kargs):
+        if _pkt:
+            type_ = orb(_pkt[5])
+            if type_ == 0x01:
+                # MS WPA IE
+                return Dot11EltMicrosoftWPA
+            elif type_ == 0x02:
+                # MS WME IE TODO
+                # return Dot11EltMicrosoftWME
+                pass
+            elif type_ == 0x04:
+                # MS WPS IE TODO
+                # return Dot11EltWPS
+                pass
+            return Dot11EltVendorSpecific
+        return cls
+
 
 # 802.11-2016 9.4.2.19