LXR linux/samples/bpf/sockex1

   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
   7struct bpf_map_def SEC("maps") my_map = {
   8        .type = BPF_MAP_TYPE_ARRAY,
   9        .key_size = sizeof(u32),
  10        .value_size = sizeof(long),
  11        .max_entries = 256,
  12};
  13
  14SEC("socket1")
  15int 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}
  29char _license[] SEC("license") = "GPL";
  30