struct sk

struct sk_buff
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Name

struct sk_buff — socket buffer

Synopsis

struct sk_buff {
  struct sk_buff * next;
  struct sk_buff * prev;
  struct sock * sk;
  struct skb_timeval tstamp;
  struct net_device * dev;
  struct net_device * input_dev;
  union h;
  union nh;
  union mac;
  struct dst_entry * dst;
  struct sec_path * sp;
  char cb[40];
  unsigned int len;
  unsigned int data_len;
  unsigned int mac_len;
  unsigned int csum;
  __u32 priority;
  __u8 local_df:1;
  __u8 cloned:1;
  __u8 ip_summed:2;
  __u8 nohdr:1;
  __u8 nfctinfo:3;
  __u8 pkt_type:3;
  __u8 fclone:2;
  __u8 ipvs_property:1;
  __be16 protocol;
  void (* destructor) (struct sk_buff *skb);
#ifdef CONFIG_NETFILTER
  __u32 nfmark;
  struct nf_conntrack * nfct;
#if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
  struct sk_buff * nfct_reasm;
#endif
#ifdef CONFIG_BRIDGE_NETFILTER
  struct nf_bridge_info * nf_bridge;
#endif
#endif
#ifdef CONFIG_NET_SCHED
  __u16 tc_index;
#ifdef CONFIG_NET_CLS_ACT
  __u16 tc_verd;
#endif
#endif
  unsigned int truesize;
  atomic_t users;
  unsigned char * head;
  unsigned char * data;
  unsigned char * tail;
  unsigned char * end;
};

Members

next: Next buffer in list
prev: Previous buffer in list
sk: Socket we are owned by
tstamp: Time we arrived
dev: Device we arrived on/are leaving by
input_dev: Device we arrived on
h: Transport layer header
nh: Network layer header
mac: Link layer header
dst: destination entry
sp: the security path, used for xfrm
cb[40]: Control buffer. Free for use by every layer. Put private vars here
len: Length of actual data
data_len: Data length
mac_len: Length of link layer header
csum: Checksum
priority: Packet queueing priority
local_df: allow local fragmentation
cloned: Head may be cloned (check refcnt to be sure)
ip_summed: Driver fed us an IP checksum
nohdr: Payload reference only, must not modify header
nfctinfo: Relationship of this skb to the connection
pkt_type: Packet class
fclone: skbuff clone status
ipvs_property: skbuff is owned by ipvs
protocol: Packet protocol from driver
destructor: Destruct function
nfmark: Can be used for communication between hooks
nfct: Associated connection, if any
nfct_reasm: netfilter conntrack re-assembly pointer
nf_bridge: Saved data about a bridged frame - see br_netfilter.c
tc_index: Traffic control index
tc_verd: traffic control verdict
truesize: Buffer size
users: User count - see {datagram,tcp}.c
head: Head of buffer
data: Data head pointer
tail: Tail pointer
end: End pointer