1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/bpf.h>
3 #include <bpf/bpf_helpers.h>
4 #include <bpf/bpf_endian.h>
5
6 int cork_byte;
7 int push_start;
8 int push_end;
9 int apply_bytes;
10 int pop_start;
11 int pop_end;
12
13 struct {
14 __uint(type, BPF_MAP_TYPE_SOCKMAP);
15 __uint(max_entries, 20);
16 __type(key, int);
17 __type(value, int);
18 } sock_map SEC(".maps");
19
20 SEC("sk_msg")
prog_sk_policy(struct sk_msg_md * msg)21 int prog_sk_policy(struct sk_msg_md *msg)
22 {
23 if (cork_byte > 0)
24 bpf_msg_cork_bytes(msg, cork_byte);
25 if (push_start > 0 && push_end > 0)
26 bpf_msg_push_data(msg, push_start, push_end, 0);
27 if (pop_start >= 0 && pop_end > 0)
28 bpf_msg_pop_data(msg, pop_start, pop_end, 0);
29
30 return SK_PASS;
31 }
32
33 SEC("sk_msg")
prog_sk_policy_redir(struct sk_msg_md * msg)34 int prog_sk_policy_redir(struct sk_msg_md *msg)
35 {
36 int two = 2;
37
38 bpf_msg_apply_bytes(msg, apply_bytes);
39 return bpf_msg_redirect_map(msg, &sock_map, two, 0);
40 }
41