root/samples/bpf/sockex1_kern.c

DEFINITIONS

1. SEC

   1 #include <uapi/linux/bpf.h>
   2 #include <uapi/linux/if_ether.h>
   3 #include <uapi/linux/if_packet.h>
   4 #include <uapi/linux/ip.h>
   5 #include "bpf_helpers.h"
   6 
   7 struct {
   8         __uint(type, BPF_MAP_TYPE_ARRAY);
   9         __type(key, u32);
  10         __type(value, long);
  11         __uint(max_entries, 256);
  12 } my_map SEC(".maps");
  13 
  14 SEC("socket1")
  15 int bpf_prog1(struct __sk_buff *skb)
  16 {
  17         int index = load_byte(skb, ETH_HLEN + offsetof(struct iphdr, protocol));
  18         long *value;
  19 
  20         if (skb->pkt_type != PACKET_OUTGOING)
  21                 return 0;
  22 
  23         value = bpf_map_lookup_elem(&my_map, &index);
  24         if (value)
  25                 __sync_fetch_and_add(value, skb->len);
  26 
  27         return 0;
  28 }
  29 char _license[] SEC("license") = "GPL";