1// SPDX-License-Identifier: GPL-2.0
2/* Copyright (c) 2022 Intel */
3
4#include <linux/bpf.h>
5#include <bpf/bpf_helpers.h>
6#include <linux/if_ether.h>
7#include "xsk_xdp_common.h"
8
9struct {
10	__uint(type, BPF_MAP_TYPE_XSKMAP);
11	__uint(max_entries, 2);
12	__uint(key_size, sizeof(int));
13	__uint(value_size, sizeof(int));
14} xsk SEC(".maps");
15
16static unsigned int idx;
17int count = 0;
18
19SEC("xdp.frags") int xsk_def_prog(struct xdp_md *xdp)
20{
21	return bpf_redirect_map(&xsk, 0, XDP_DROP);
22}
23
24SEC("xdp.frags") int xsk_xdp_drop(struct xdp_md *xdp)
25{
26	/* Drop every other packet */
27	if (idx++ % 2)
28		return XDP_DROP;
29
30	return bpf_redirect_map(&xsk, 0, XDP_DROP);
31}
32
33SEC("xdp.frags") int xsk_xdp_populate_metadata(struct xdp_md *xdp)
34{
35	void *data, *data_meta;
36	struct xdp_info *meta;
37	int err;
38
39	/* Reserve enough for all custom metadata. */
40	err = bpf_xdp_adjust_meta(xdp, -(int)sizeof(struct xdp_info));
41	if (err)
42		return XDP_DROP;
43
44	data = (void *)(long)xdp->data;
45	data_meta = (void *)(long)xdp->data_meta;
46
47	if (data_meta + sizeof(struct xdp_info) > data)
48		return XDP_DROP;
49
50	meta = data_meta;
51	meta->count = count++;
52
53	return bpf_redirect_map(&xsk, 0, XDP_DROP);
54}
55
56SEC("xdp") int xsk_xdp_shared_umem(struct xdp_md *xdp)
57{
58	void *data = (void *)(long)xdp->data;
59	void *data_end = (void *)(long)xdp->data_end;
60	struct ethhdr *eth = data;
61
62	if (eth + 1 > data_end)
63		return XDP_DROP;
64
65	/* Redirecting packets based on the destination MAC address */
66	idx = ((unsigned int)(eth->h_dest[5])) / 2;
67	if (idx > MAX_SOCKETS)
68		return XDP_DROP;
69
70	return bpf_redirect_map(&xsk, idx, XDP_DROP);
71}
72
73char _license[] SEC("license") = "GPL";
74