Helmut Grohne Helmut Grohne - 6 months ago 26
Python Question

How to pickle a scapy packet?

I need to pickle a

scapy
packet. Most of the time this works, but sometimes the pickler complains about a function object. As a rule of thumb: ARP packets pickle fine. Some UDP packets are problematic.

Answer

My solution (as inspired by the scapy mailing list) is as follows:

class PicklablePacket:
    """A container for scapy packets that can be pickled (in contrast
    to scapy packets themselves)."""
    def __init__(self, pkt):
        self.contents = str(pkt)
        self.time = pkt.time

    def __call__(self):
        """Get the original scapy packet."""
        pkt = scapy.Ether(self.contents)
        pkt.time = self.time
        return pkt

Anywhere I wish to pass a scapy Packet through a Queue I simply wrap it in a PicklablePacket and __call__ it afterwards. I am not aware of data that is not retained this way. However this approach only works with Ethernet packets. (All packets sniffed on a regular NIC (not WLAN) are Ethernet.) It could probably be extended to work for other types, too.

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