Fragment SOME/IP-TP

def fragment(self, fragsize=1392):
        """Fragment SOME/IP-TP"""
        fnb = 0
        fl = self
        lst = list()
        while fl.underlayer is not None:
            fnb += 1
            fl = fl.underlayer

        for p in fl:
            s = raw(p[fnb].payload)
            nb = (len(s) + fragsize) // fragsize
            for i in range(nb):
                q = p.copy()
                del q[fnb].payload
                q[fnb].len = SOMEIP.LEN_OFFSET_TP + \
                    len(s[i * fragsize:(i + 1) * fragsize])
                q[fnb].more_seg = 1
                if i == nb - 1:
                    q[fnb].more_seg = 0
                q[fnb].offset += i * fragsize // 16
                r = conf.raw_layer(load=s[i * fragsize:(i + 1) * fragsize])
                r.overload_fields = p[fnb].payload.overload_fields.copy()
                q.add_payload(r)
                lst.append(q)

        return lst