I've implemented a protocol (Packet) in Scapy, which is does send its defined fields as well as its app_data inverted and non-inverted on the wire. To signal my protocol to invert the app_data, I want to use a simple flag attribute that is set on creation (+1 if also able to do this on an existing object and rebuild it). This has to take place in the post_build method of the packet, because I need to generate an security_code over the app_data later.. The Problem is that I can't write a packet with inverted app_data using wrpcap(). It seems that wrpcap() does make a copy of the given object and the invert attribute isn't copied.. When debugging with id(), it turned out that the object I created and passed to wrpcap() is different from the one that is actually written. So unfortunately, when I try to write this object with inverted app_data, this flag is not set - holds the default value. pkt = MyProto(invert = True, app_data = b'Hello', ...) wrpcap(file, pkt, append=True) # id(pkt) = 123 # pkt.inverted = True ... class MyProto(Packet): inverted = False ... def post_build(self, pkt, pay): # id(self) = 789 # self.inverted = False Now, which approach will give me the solution. I can imagine adding an additional field that is copied in wrpcap's deepcopy process, but that involves additional logic within my __init__ and post_build methods, is not clean and may not be the right way to go. Somebody an Idea? Continue reading...
