import struct
import socket
from common import checksum
class UDP(object):
def __init__(self, src, dst, payload=''):
self.srcp = src
self.dstp = dst
self.payload = payload
self.checksum = 0
self.length = 8 # UDP Header length
def pack(self, src, dst, proto=socket.IPPROTO_UDP):
length = self.length + len(self.payload)
pseudo_header = struct.pack('!4s4sBBH', src, dst, 0,
proto, length)
self.checksum = checksum(pseudo_header)
packet = struct.pack('!HHHH',
self.srcp, self.dstp, length, 0)
return packet
