Method addfield

scapy/fields.py:232–247

Add an internal value to a string Copy the network representation of field `val` (belonging to layer `pkt`) to the raw string packet `s`, and return the new string packet.

(self, pkt, s, val)

        return repr(self.i2h(pkt, x))

    def addfield(self, pkt, s, val):
        # type: (Packet, bytes, Optional[I]) -> bytes
        """Add an internal value to a string

        Copy the network representation of field `val` (belonging to layer
        `pkt`) to the raw string packet `s`, and return the new string packet.
        """
        try:
            return s + self.struct.pack(self.i2m(pkt, val))
        except struct.error as ex:
            raise ValueError(
                "Incorrect type of value for field %s:\n" % self.name +
                "struct.error('%s')\n" % ex +
                "To inject bytes into the field regardless of the type, " +
                "use RawVal. See help(RawVal)"
            )

    def getfield(self, pkt, s):
        # type: (Packet, bytes) -> Tuple[bytes, I]