Testing Scapy

scapy_test.py

from scapy.all import *


class Header(Packet):
    name = 'Header'
    fields_desc = [
        ByteField('cmd', 0),
        ByteField('status', 0)
    ]


class FooBody(Packet):
    name = 'FooBody'
    fields_desc = [
        ByteField('foo_1', 0),
        ByteField('foo_2', 0)
    ]


class BarBody(Packet):
    name = 'BarBody'
    fields_desc = [
        ByteField('bar_1', 0),
        ByteField('bar_2', 0)
    ]


class UnResult(Packet):
    name = 'UnResult'
    fields_desc = [
        ByteField('type', 0)
    ]

    
bind_layers(UnResult, FooBody, type=0x00)
bind_layers(UnResult, BarBody, type=0x01)


class Command(Header):
    name = 'Result'
    fields_desc = Header.fields_desc.copy() + [
        PacketField('result', 0, UnResult)
    ]


if __name__ == '__main__':
    headerBytes = b'\x01\x02'
    resultBytesFoo = b'\x00\x06\x06'
    resultBytesBar = b'\x01\x06\x06'

    # Dissecting
    
    c = Command(headerBytes + resultBytesFoo)
    assert c.cmd == 0x01
    assert c.status == 0x02
    assert c.result.type == 0x00
    assert c.result.foo_1 == 0x06
    assert c.result.foo_2 == 0x06

    c = Command(headerBytes + resultBytesBar)
    assert c.cmd == 0x01
    assert c.status == 0x02
    assert c.result.type == 0x01
    assert c.result.bar_1 == 0x06
    assert c.result.bar_2 == 0x06

    # Building

    # This works 
    c = Command(cmd=1, status=2, result=UnResult(b'\x00\x06\x06'))
    print(c.show())
    c = Command(cmd=1, status=2, result=(UnResult(type=1) / BarBody(bar_1=6, bar_2=6)))
    print(c.show())