'check to see if this packet is to/from an IP in a session,
if so write it. the packet will be passed in the \'raw\' kwarg'

def __callback(self, addr, pkt, ts, raw=None, **kw):

    if (addr[0][0] in self.sessions):
        ip = addr[0][0]
    elif (addr[1][0] in self.sessions):
        ip = addr[1][0]
    else:
        return
    for s in self.sessions[ip].values():
        s.sessionpackets += 1
        s.sessionbytes += len(raw)
    if self.subDecoder:
        self.subDecoder.decode(len(raw), str(raw), ts)
    else:
        self.dump(raw, ts)
