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
8struct {
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
15SEC("xdp")
16int xdp_redir_prog(struct xdp_md *ctx)
17{
18	return bpf_redirect_map(&cpu_map, 1, 0);
19}
20
21SEC("xdp")
22int xdp_dummy_prog(struct xdp_md *ctx)
23{
24	return XDP_PASS;
25}
26
27SEC("xdp/cpumap")
28int 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
36SEC("xdp.frags/cpumap")
37int xdp_dummy_cm_frags(struct xdp_md *ctx)
38{
39	return XDP_PASS;
40}
41
42char _license[] SEC("license") = "GPL";
43