ipv6.py 文件源码

def serialize(self, payload, prev):
        hdr = bytearray(40)
        v_tc_flow = (self.version << 28 | self.traffic_class << 20 |
                     self.flow_label)
        struct.pack_into(ipv6._PACK_STR, hdr, 0, v_tc_flow,
                         self.payload_length, self.nxt, self.hop_limit,
                         addrconv.ipv6.text_to_bin(self.src),
                         addrconv.ipv6.text_to_bin(self.dst))
        if self.ext_hdrs:
            for ext_hdr in self.ext_hdrs:
                hdr.extend(ext_hdr.serialize())
        if 0 == self.payload_length:
            payload_length = len(payload)
            for ext_hdr in self.ext_hdrs:
                payload_length += len(ext_hdr)
            self.payload_length = payload_length
            struct.pack_into('!H', hdr, 4, self.payload_length)
        return hdr