Linux学习之网络报文sk_buff结构

一、sk_buff的结构图如下

 

二.sk_buff结构基本操作

     1、skb_headroom(), skb_tailroom() 

    原型/描述

int skb_headroom(const struct sk_buff *skb);

   bytes at buffer head

int skb_tailroom(const struct sk_buff *skb);

  bytes at buffer

     示图

2、skb_reserve()

原型 

void skb_reserve(struct sk_buff *skb, unsigned int len);

描述 

       adjust headroom

示图 

 

3、skb_push()

原型

unsigned char *skb_push(struct sk_buff *skb, unsigned int len);

描述 

add data to the start of a buffer

示图

 

4、skb_pull()

原型 

unsigned char *skb_pull(struct sk_buff *skb, unsigned int len);

描述 

remove data from the start of a buffer

示图 

 

5、skb_put()

原型

unsigned char *skb_put(struct sk_buff *skb, unsigned int len);

描述 

add data to a buffer

示图 

6、skb_trim()

原型 

void skb_trim(struct sk_buff *skb, unsigned int len);

描述 

remove end from a buffer

示图

三.sk_buff 链表 

    1、skb_queue_len, skb_peek, skb_peek_tail

          原型 / 描述

__u32 skb_queue_len(const struct sk_buff_head *list_);

                      get queue length

struct sk_buff *skb_peek(struct sk_buff_head *list);

                      get pointer to the head element

struct sk_buff *skb_peek_tail(struct sk_buff_head *list);

                      get pointer to the tail element

   示图 

 

 

2、skb_queue_head()

   原型    

   void skb_queue_head(struct sk_buff_head *list, struct sk_buff *newsk);   

  描述

          queue a buffer at the list head

  示图

 

3、skb_queue_tail()

      原型     

     void skb_queue_tail(struct sk_buff_head *list, struct sk_buff *newsk);

      描述

queue a buffer at the list ta

         示图

 

4、skb_dequeue()

原型

struct sk_buff *skb_dequeue(struct sk_buff_head *list);

描述

remove from the head of the queue

示图

 

5、skb_dequeue_tail()

原型

struct sk_buff *skb_dequeue_tail(struct sk_buff_head *list);

描述

remove from the tail of the queue

示图

 

6、skb_insert()

原型 

void skb_insert(struct sk_buff *old, struct sk_buff *newsk);

描述

insert a buffer

示图 

7、skb_append()

原型 

void skb_append(struct sk_buff *old, struct sk_buff *newsk);

描述

append a buffer

示图

 

8、skb_unlink()

原型

void skb_unlink(struct sk_buff *skb);

描述 

remove a buffer from a list

示图