1 | // SPDX-License-Identifier: GPL-2.0 |
2 | |
3 | #include <linux/bpf.h> |
4 | #include <bpf/bpf_helpers.h> |
5 | |
6 | #define IFINDEX_LO 1 |
7 | |
8 | struct { |
9 | __uint(type, BPF_MAP_TYPE_CPUMAP); |
10 | __uint(key_size, sizeof(__u32)); |
11 | __uint(value_size, sizeof(struct bpf_cpumap_val)); |
12 | __uint(max_entries, 4); |
13 | } cpu_map SEC(".maps" ); |
14 | |
15 | SEC("xdp" ) |
16 | int xdp_redir_prog(struct xdp_md *ctx) |
17 | { |
18 | return bpf_redirect_map(&cpu_map, 1, 0); |
19 | } |
20 | |
21 | SEC("xdp" ) |
22 | int xdp_dummy_prog(struct xdp_md *ctx) |
23 | { |
24 | return XDP_PASS; |
25 | } |
26 | |
27 | SEC("xdp/cpumap" ) |
28 | int xdp_dummy_cm(struct xdp_md *ctx) |
29 | { |
30 | if (ctx->ingress_ifindex == IFINDEX_LO) |
31 | return XDP_DROP; |
32 | |
33 | return XDP_PASS; |
34 | } |
35 | |
36 | SEC("xdp.frags/cpumap" ) |
37 | int xdp_dummy_cm_frags(struct xdp_md *ctx) |
38 | { |
39 | return XDP_PASS; |
40 | } |
41 | |
42 | char _license[] SEC("license" ) = "GPL" ; |
43 | |