1 #include <linux/bpf.h>
2 #include <bpf/bpf_helpers.h>
3 #include <bpf/bpf_endian.h>
4
5 struct {
6 __uint(type, BPF_MAP_TYPE_SOCKMAP);
7 __uint(max_entries, 20);
8 __type(key, int);
9 __type(value, int);
10 } sock_map_rx SEC(".maps");
11
12 struct {
13 __uint(type, BPF_MAP_TYPE_SOCKMAP);
14 __uint(max_entries, 20);
15 __type(key, int);
16 __type(value, int);
17 } sock_map_tx SEC(".maps");
18
19 struct {
20 __uint(type, BPF_MAP_TYPE_SOCKMAP);
21 __uint(max_entries, 20);
22 __type(key, int);
23 __type(value, int);
24 } sock_map_msg SEC(".maps");
25
26 struct {
27 __uint(type, BPF_MAP_TYPE_ARRAY);
28 __uint(max_entries, 20);
29 __type(key, int);
30 __type(value, int);
31 } sock_map_break SEC(".maps");
32
33 SEC("sk_skb2")
bpf_prog2(struct __sk_buff * skb)34 int bpf_prog2(struct __sk_buff *skb)
35 {
36 void *data_end = (void *)(long) skb->data_end;
37 void *data = (void *)(long) skb->data;
38 __u32 lport = skb->local_port;
39 __u32 rport = skb->remote_port;
40 __u8 *d = data;
41 __u8 sk, map;
42
43 if (data + 8 > data_end)
44 return SK_DROP;
45
46 map = d[0];
47 sk = d[1];
48
49 d[0] = 0xd;
50 d[1] = 0xe;
51 d[2] = 0xa;
52 d[3] = 0xd;
53 d[4] = 0xb;
54 d[5] = 0xe;
55 d[6] = 0xe;
56 d[7] = 0xf;
57
58 if (!map)
59 return bpf_sk_redirect_map(skb, &sock_map_rx, sk, 0);
60 return bpf_sk_redirect_map(skb, &sock_map_tx, sk, 0);
61 }
62
63 char _license[] SEC("license") = "GPL";
64