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")
xdp_redirect_map_0(struct xdp_md * 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")
xdp_redirect_map_1(struct xdp_md * 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")
xdp_redirect_map_2(struct xdp_md * 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
xdp_count(struct xdp_md * xdp,__u32 key)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")
xdp_count_0(struct xdp_md * xdp)62 int xdp_count_0(struct xdp_md *xdp)
63 {
64 return xdp_count(xdp, 0);
65 }
66
67 SEC("xdp")
xdp_count_1(struct xdp_md * xdp)68 int xdp_count_1(struct xdp_md *xdp)
69 {
70 return xdp_count(xdp, 1);
71 }
72
73 SEC("xdp")
xdp_count_2(struct xdp_md * 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
store_mac(struct xdp_md * xdp,__u32 id)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")
store_mac_1(struct xdp_md * xdp)108 int store_mac_1(struct xdp_md *xdp)
109 {
110 return store_mac(xdp, 0);
111 }
112
113 SEC("xdp")
store_mac_2(struct xdp_md * 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