1 // SPDX-License-Identifier: GPL-2.0
2 // Copyright (c) 2020 Cloudflare
3
4 #include <errno.h>
5 #include <stdbool.h>
6 #include <linux/bpf.h>
7
8 #include <bpf/bpf_helpers.h>
9
10 struct {
11 __uint(type, BPF_MAP_TYPE_SOCKMAP);
12 __uint(max_entries, 2);
13 __type(key, __u32);
14 __type(value, __u64);
15 } sock_map SEC(".maps");
16
17 struct {
18 __uint(type, BPF_MAP_TYPE_SOCKHASH);
19 __uint(max_entries, 2);
20 __type(key, __u32);
21 __type(value, __u64);
22 } sock_hash SEC(".maps");
23
24 struct {
25 __uint(type, BPF_MAP_TYPE_ARRAY);
26 __uint(max_entries, 2);
27 __type(key, int);
28 __type(value, unsigned int);
29 } verdict_map SEC(".maps");
30
31 static volatile bool test_sockmap; /* toggled by user-space */
32
33 SEC("sk_skb/stream_parser")
prog_skb_parser(struct __sk_buff * skb)34 int prog_skb_parser(struct __sk_buff *skb)
35 {
36 return skb->len;
37 }
38
39 SEC("sk_skb/stream_verdict")
prog_skb_verdict(struct __sk_buff * skb)40 int prog_skb_verdict(struct __sk_buff *skb)
41 {
42 unsigned int *count;
43 __u32 zero = 0;
44 int verdict;
45
46 if (test_sockmap)
47 verdict = bpf_sk_redirect_map(skb, &sock_map, zero, 0);
48 else
49 verdict = bpf_sk_redirect_hash(skb, &sock_hash, &zero, 0);
50
51 count = bpf_map_lookup_elem(&verdict_map, &verdict);
52 if (count)
53 (*count)++;
54
55 return verdict;
56 }
57
58 SEC("sk_msg")
prog_msg_verdict(struct sk_msg_md * msg)59 int prog_msg_verdict(struct sk_msg_md *msg)
60 {
61 unsigned int *count;
62 __u32 zero = 0;
63 int verdict;
64
65 if (test_sockmap)
66 verdict = bpf_msg_redirect_map(msg, &sock_map, zero, 0);
67 else
68 verdict = bpf_msg_redirect_hash(msg, &sock_hash, &zero, 0);
69
70 count = bpf_map_lookup_elem(&verdict_map, &verdict);
71 if (count)
72 (*count)++;
73
74 return verdict;
75 }
76
77 SEC("sk_reuseport")
prog_reuseport(struct sk_reuseport_md * reuse)78 int prog_reuseport(struct sk_reuseport_md *reuse)
79 {
80 unsigned int *count;
81 int err, verdict;
82 __u32 zero = 0;
83
84 if (test_sockmap)
85 err = bpf_sk_select_reuseport(reuse, &sock_map, &zero, 0);
86 else
87 err = bpf_sk_select_reuseport(reuse, &sock_hash, &zero, 0);
88 verdict = err ? SK_DROP : SK_PASS;
89
90 count = bpf_map_lookup_elem(&verdict_map, &verdict);
91 if (count)
92 (*count)++;
93
94 return verdict;
95 }
96
97 int _version SEC("version") = 1;
98 char _license[] SEC("license") = "GPL";
99