LLTD: implement LLTDQueryLargeTlv & LLTDQueryLargeTlvResp

scapy/layers/lltd.py

@@ -12,9 +12,9 @@ https://msdn.microsoft.com/en-us/library/cc233983.aspx
 import struct
 
 from scapy.fields import BitField, FlagsField, ByteField, ByteEnumField, \
-    ShortField, ShortEnumField, IntField, IntEnumField, LongField, \
-    MultiEnumField, FieldLenField, FieldListField, PacketListField, \
-    StrLenField, StrLenFieldUtf16, ConditionalField, MACField
+    ShortField, ShortEnumField, ThreeBytesField, IntField, IntEnumField, \
+    LongField, MultiEnumField, FieldLenField, FieldListField, \
+    PacketListField, StrLenField, StrLenFieldUtf16, ConditionalField, MACField
 from scapy.packet import Packet, Padding, bind_layers
 from scapy.layers.l2 import Ether
 from scapy.layers.inet import IPField
@@ -181,6 +181,48 @@ class LLTDQueryResp(Packet):
         ), [LLTD]
 
 
+class LLTDQueryLargeTlv(Packet):
+    name = "LLTD - Query Large Tlv"
+    fields_desc = [
+        ByteEnumField("type", 14, {
+            14: "Icon image",
+            17: "Friendly Name",
+            19: "Hardware ID",
+            22: "AP Association Table",
+            24: "Detailed Icon Image",
+            26: "Component Table",
+            28: "Repeater AP Table",
+        }),
+        ThreeBytesField("offset", 0),
+    ]
+
+    def mysummary(self):
+        return self.sprintf("%type% (offset %offset%)"), [LLTD]
+
+
+class LLTDQueryLargeTlvResp(Packet):
+    name = "LLTD - Query Large Tlv Response"
+    fields_desc = [
+        FlagsField("flags", 0, 2, "RM"),
+        BitField("len", None, 14),
+        StrLenField("value", "", length_from=lambda pkt: pkt.len)
+    ]
+
+    def post_build(self, pkt, pay):
+        if self.len is None:
+            # len should be a FieldLenField but has an unsupported
+            # format (14 bits)
+            flags = ord(pkt[0]) & 0xc0
+            length = len(self.value)
+            pkt = chr(flags + (length >> 8)) + chr(length % 256) + pkt[2:]
+        return pkt + pay
+
+    def mysummary(self):
+        return self.sprintf("%%len%% bytes%s" % (
+            " (last)" if not self.flags & 2 else ""
+        )), [LLTD]
+
+
 class LLTDAttribute(Packet):
     name = "LLTD Attribute"
     show_indent = False
@@ -668,6 +710,8 @@ bind_layers(LLTD, LLTDHello, tos=0, function=1)
 bind_layers(LLTD, LLTDHello, tos=1, function=1)
 bind_layers(LLTD, LLTDEmit, tos=0, function=2)
 bind_layers(LLTD, LLTDQueryResp, tos=0, function=7)
+bind_layers(LLTD, LLTDQueryLargeTlv, tos=0, function=11)
+bind_layers(LLTD, LLTDQueryLargeTlvResp, tos=0, function=12)
 bind_layers(LLTDHello, LLTDAttribute)
 bind_layers(LLTDAttribute, LLTDAttribute)
 bind_layers(LLTDAttribute, Padding, type=0)