xref: /linux/tools/testing/selftests/bpf/progs/xdp_redirect_map.c (revision bbfd5594756011167b8f8de9a00e0c946afda1e6)
1 // SPDX-License-Identifier: GPL-2.0
2 
3 #include <linux/if_ether.h>
4 
5 #include <linux/bpf.h>
6 #include <bpf/bpf_helpers.h>
7 #include <bpf/bpf_endian.h>
8 
9 struct {
10 	__uint(type, BPF_MAP_TYPE_DEVMAP);
11 	__uint(max_entries, 8);
12 	__uint(key_size, sizeof(int));
13 	__uint(value_size, sizeof(int));
14 } tx_port SEC(".maps");
15 
16 SEC("xdp")
17 int xdp_redirect_map_0(struct xdp_md *xdp)
18 {
19 	return bpf_redirect_map(&tx_port, 0, 0);
20 }
21 
22 SEC("xdp")
23 int xdp_redirect_map_1(struct xdp_md *xdp)
24 {
25 	return bpf_redirect_map(&tx_port, 1, 0);
26 }
27 
28 SEC("xdp")
29 int xdp_redirect_map_2(struct xdp_md *xdp)
30 {
31 	return bpf_redirect_map(&tx_port, 2, 0);
32 }
33 
34 struct {
35 	__uint(type, BPF_MAP_TYPE_ARRAY);
36 	__uint(max_entries, 3);
37 	__type(key, __u32);
38 	__type(value, __u64);
39 } rxcnt SEC(".maps");
40 
41 static int xdp_count(struct xdp_md *xdp, __u32 key)
42 {
43 	void *data_end = (void *)(long)xdp->data_end;
44 	void *data = (void *)(long)xdp->data;
45 	struct ethhdr *eth = data;
46 	__u64 *count;
47 
48 	if (data + sizeof(*eth) > data_end)
49 		return XDP_DROP;
50 
51 	if (bpf_htons(eth->h_proto) == ETH_P_IP) {
52 		/* We only count IPv4 packets */
53 		count = bpf_map_lookup_elem(&rxcnt, &key);
54 		if (count)
55 			*count += 1;
56 	}
57 
58 	return XDP_PASS;
59 }
60 
61 SEC("xdp")
62 int xdp_count_0(struct xdp_md *xdp)
63 {
64 	return xdp_count(xdp, 0);
65 }
66 
67 SEC("xdp")
68 int xdp_count_1(struct xdp_md *xdp)
69 {
70 	return xdp_count(xdp, 1);
71 }
72 
73 SEC("xdp")
74 int xdp_count_2(struct xdp_md *xdp)
75 {
76 	return xdp_count(xdp, 2);
77 }
78 
79 struct {
80 	__uint(type, BPF_MAP_TYPE_ARRAY);
81 	__uint(max_entries, 2);
82 	__type(key, __u32);
83 	__type(value, __be64);
84 } rx_mac SEC(".maps");
85 
86 static int store_mac(struct xdp_md *xdp, __u32 id)
87 {
88 	void *data_end = (void *)(long)xdp->data_end;
89 	void *data = (void *)(long)xdp->data;
90 	struct ethhdr *eth = data;
91 	__u32 key = id;
92 	__be64 mac = 0;
93 
94 	if (data + sizeof(*eth) > data_end)
95 		return XDP_DROP;
96 
97 	/* Only store IPv4 MAC to avoid being polluted by IPv6 packets */
98 	if (eth->h_proto == bpf_htons(ETH_P_IP)) {
99 		__builtin_memcpy(&mac, eth->h_source, ETH_ALEN);
100 		bpf_map_update_elem(&rx_mac, &key, &mac, 0);
101 		bpf_printk("%s - %x", __func__, mac);
102 	}
103 
104 	return XDP_PASS;
105 }
106 
107 SEC("xdp")
108 int store_mac_1(struct xdp_md *xdp)
109 {
110 	return store_mac(xdp, 0);
111 }
112 
113 SEC("xdp")
114 int store_mac_2(struct xdp_md *xdp)
115 {
116 	return store_mac(xdp, 1);
117 }
118 
119 char _license[] SEC("license") = "GPL";
120