/* include/linux/skbuff.h */
struct sk_buff_head
{
/* These two members must be first. */
struct sk_buff * next;
struct sk_buff * prev;
__u32 qlen;
spinlock_t lock;
};
struct sk_buff
{
/* These two members must be first. */
struct sk_buff * next; /* Next buffer in list */
struct sk_buff * prev; /* Previous buffer in list */
struct sk_buff_head * list; /* List we are on */
struct sock *sk; /* Socket we are owned by */
struct timeval stamp; /* Time we arrived */
struct net_device *dev; /* Device we arrived on/are leaving by */
/* Transport layer header */
union
{
struct tcphdr *th;
struct udphdr *uh;
struct icmphdr *icmph;
struct igmphdr *igmph;
struct iphdr *ipiph;
struct spxhdr *spxh;
unsigned char *raw;
}
h;
/* Network layer header */
union
{
struct iphdr *iph;
struct ipv6hdr *ipv6h;
struct arphdr *arph;
struct ipxhdr *ipxh;
unsigned char *raw;
}
nh;
/* Link layer header */
union
{
struct ethhdr *ethernet;
unsigned char *raw;
}
mac;
struct dst_entry *dst;
/*
* This is the control buffer. It is free to use for every
* layer. Please put your private variables there. If you
* want to keep them across layers you have to do a skb_clone()
* first. This is owned by whoever has the skb queued ATM.
*/
char cb[48];
unsigned int len; /* Length of actual data */
unsigned int csum; /* Checksum */
volatile char used; /* Data moved to user and not MSG_PEEK */
unsigned char cloned, /* head may be cloned (check refcnt to be sure). */
pkt_type, /* Packet class */
ip_summed; /* Driver fed us an IP checksum */
__u32 priority; /* Packet queueing priority */
atomic_t users; /* User count - see datagram.c,tcp.c */
unsigned short protocol; /* Packet protocol from driver. */
unsigned short security; /* Security level of packet */
unsigned int truesize; /* Buffer size */
unsigned char *head; /* Head of buffer */
unsigned char *data; /* Data head pointer */
unsigned char *tail; /* Tail pointer */
unsigned char *end; /* End pointer */
void (*destructor)(struct sk_buff *); /* Destruct function */
#ifdef CONFIG_NETFILTER /* Can be used for communication between hooks. */
unsigned long nfmark; /* Cache info */
__u32 nfcache; /* Associated connection, if any */
struct nf_ct_info *nfct;
#ifdef CONFIG_NETFILTER_DEBUG
unsigned int nf_debug;
#endif
#endif /*CONFIG_NETFILTER*/
#if defined(CONFIG_HIPPI)
union
{
__u32 ifield;
}
private;
#endif
#ifdef CONFIG_NET_SCHED
__u32 tc_index; /* traffic control index */
#endif
};