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
15__u32 redirect_count = 0;
16
17SEC("xdp")
18int xdp_redir_prog(struct xdp_md *ctx)
19{
20	return bpf_redirect_map(&cpu_map, 0, 0);
21}
22
23SEC("xdp")
24int xdp_dummy_prog(struct xdp_md *ctx)
25{
26	return XDP_PASS;
27}
28
29SEC("xdp/cpumap")
30int xdp_dummy_cm(struct xdp_md *ctx)
31{
32	if (bpf_get_smp_processor_id() == 0)
33		redirect_count++;
34
35	if (ctx->ingress_ifindex == IFINDEX_LO)
36		return XDP_DROP;
37
38	return XDP_PASS;
39}
40
41SEC("xdp.frags/cpumap")
42int xdp_dummy_cm_frags(struct xdp_md *ctx)
43{
44	return XDP_PASS;
45}
46
47char _license[] SEC("license") = "GPL";