1. 根目录:
2. include
3. linux
4. netfilter
5. xt_length.h

#ifndef _XT_LENGTH_H
#define _XT_LENGTH_H

#include <linux/types.h>

struct xt_length_info {
    __u16	min, max;
    __u8	invert;
};

#endif /*_XT_LENGTH_H*/