packet_utils.py 文件源码

def checksum(data):
    data = six.binary_type(data)    # input can be bytearray.
    if len(data) % 2:
        data += b'\x00'

    s = sum(array.array('H', data))
    s = (s & 0xffff) + (s >> 16)
    s += (s >> 16)
    return socket.ntohs(~s & 0xffff)


# avoid circular import