Class CoAP

scapy/contrib/coap.py:212–236

class CoAP(Packet):
    __slots__ = ["content_format"]
    name = "CoAP"

    fields_desc = [BitField("ver", 1, 2),
                   BitEnumField("type", 0, 2, {0: "CON", 1: "NON", 2: "ACK", 3: "RST"}),  # noqa: E501
                   BitFieldLenField("tkl", None, 4, length_of='token'),
                   ByteEnumField("code", 0, coap_codes),
                   ShortField("msg_id", 0),
                   StrLenField("token", "", length_from=lambda pkt: pkt.tkl),
                   _CoAPOptsField("options", []),
                   _CoAPPaymark("paymark", b"")
                   ]

    def getfieldval(self, attr):
        v = getattr(self, attr)
        if v:
            return v
        return Packet.getfieldval(self, attr)

    def post_dissect(self, pay):
        for k in self.options:
            if k[0] == "Content-Format":
                self.content_format = k[1]
        return pay


bind_layers(UDP, CoAP, sport=5683)