xref: /openbmc/linux/samples/bpf/sockex1_kern.c (revision 6c33a6f4)
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/bpf_helpers.h>
6 #include "bpf_legacy.h"
7 
8 struct {
9 	__uint(type, BPF_MAP_TYPE_ARRAY);
10 	__type(key, u32);
11 	__type(value, long);
12 	__uint(max_entries, 256);
13 } my_map SEC(".maps");
14 
15 SEC("socket1")
16 int bpf_prog1(struct __sk_buff *skb)
17 {
18 	int index = load_byte(skb, ETH_HLEN + offsetof(struct iphdr, protocol));
19 	long *value;
20 
21 	if (skb->pkt_type != PACKET_OUTGOING)
22 		return 0;
23 
24 	value = bpf_map_lookup_elem(&my_map, &index);
25 	if (value)
26 		__sync_fetch_and_add(value, skb->len);
27 
28 	return 0;
29 }
30 char _license[] SEC("license") = "GPL";
31