1 // SPDX-License-Identifier: GPL-2.0
2
3 #include <stdbool.h>
4 #include <linux/bpf.h>
5 #include <linux/netdev.h>
6 #include <bpf/bpf_helpers.h>
7 #include <bpf/bpf_endian.h>
8 #include <bpf/bpf_tracing.h>
9 #include <linux/if_ether.h>
10 #include <linux/ip.h>
11 #include <linux/ipv6.h>
12 #include <linux/in.h>
13 #include <linux/in6.h>
14 #include <linux/udp.h>
15 #include <asm-generic/errno-base.h>
16
17 #include "xdp_features.h"
18
19 #define ipv6_addr_equal(a, b) ((a).s6_addr32[0] == (b).s6_addr32[0] && \
20 (a).s6_addr32[1] == (b).s6_addr32[1] && \
21 (a).s6_addr32[2] == (b).s6_addr32[2] && \
22 (a).s6_addr32[3] == (b).s6_addr32[3])
23
24 struct net_device;
25 struct bpf_prog;
26
27 struct xdp_cpumap_stats {
28 unsigned int redirect;
29 unsigned int pass;
30 unsigned int drop;
31 };
32
33 struct {
34 __uint(type, BPF_MAP_TYPE_ARRAY);
35 __type(key, __u32);
36 __type(value, __u32);
37 __uint(max_entries, 1);
38 } stats SEC(".maps");
39
40 struct {
41 __uint(type, BPF_MAP_TYPE_ARRAY);
42 __type(key, __u32);
43 __type(value, __u32);
44 __uint(max_entries, 1);
45 } dut_stats SEC(".maps");
46
47 struct {
48 __uint(type, BPF_MAP_TYPE_CPUMAP);
49 __uint(key_size, sizeof(__u32));
50 __uint(value_size, sizeof(struct bpf_cpumap_val));
51 __uint(max_entries, 1);
52 } cpu_map SEC(".maps");
53
54 struct {
55 __uint(type, BPF_MAP_TYPE_DEVMAP);
56 __uint(key_size, sizeof(__u32));
57 __uint(value_size, sizeof(struct bpf_devmap_val));
58 __uint(max_entries, 1);
59 } dev_map SEC(".maps");
60
61 const volatile struct in6_addr tester_addr;
62 const volatile struct in6_addr dut_addr;
63
64 static __always_inline int
xdp_process_echo_packet(struct xdp_md * xdp,bool dut)65 xdp_process_echo_packet(struct xdp_md *xdp, bool dut)
66 {
67 void *data_end = (void *)(long)xdp->data_end;
68 void *data = (void *)(long)xdp->data;
69 struct ethhdr *eh = data;
70 struct tlv_hdr *tlv;
71 struct udphdr *uh;
72 __be16 port;
73
74 if (eh + 1 > (struct ethhdr *)data_end)
75 return -EINVAL;
76
77 if (eh->h_proto == bpf_htons(ETH_P_IP)) {
78 struct iphdr *ih = (struct iphdr *)(eh + 1);
79 __be32 saddr = dut ? tester_addr.s6_addr32[3]
80 : dut_addr.s6_addr32[3];
81 __be32 daddr = dut ? dut_addr.s6_addr32[3]
82 : tester_addr.s6_addr32[3];
83
84 ih = (struct iphdr *)(eh + 1);
85 if (ih + 1 > (struct iphdr *)data_end)
86 return -EINVAL;
87
88 if (saddr != ih->saddr)
89 return -EINVAL;
90
91 if (daddr != ih->daddr)
92 return -EINVAL;
93
94 if (ih->protocol != IPPROTO_UDP)
95 return -EINVAL;
96
97 uh = (struct udphdr *)(ih + 1);
98 } else if (eh->h_proto == bpf_htons(ETH_P_IPV6)) {
99 struct in6_addr saddr = dut ? tester_addr : dut_addr;
100 struct in6_addr daddr = dut ? dut_addr : tester_addr;
101 struct ipv6hdr *ih6 = (struct ipv6hdr *)(eh + 1);
102
103 if (ih6 + 1 > (struct ipv6hdr *)data_end)
104 return -EINVAL;
105
106 if (!ipv6_addr_equal(saddr, ih6->saddr))
107 return -EINVAL;
108
109 if (!ipv6_addr_equal(daddr, ih6->daddr))
110 return -EINVAL;
111
112 if (ih6->nexthdr != IPPROTO_UDP)
113 return -EINVAL;
114
115 uh = (struct udphdr *)(ih6 + 1);
116 } else {
117 return -EINVAL;
118 }
119
120 if (uh + 1 > (struct udphdr *)data_end)
121 return -EINVAL;
122
123 port = dut ? uh->dest : uh->source;
124 if (port != bpf_htons(DUT_ECHO_PORT))
125 return -EINVAL;
126
127 tlv = (struct tlv_hdr *)(uh + 1);
128 if (tlv + 1 > data_end)
129 return -EINVAL;
130
131 return bpf_htons(tlv->type) == CMD_ECHO ? 0 : -EINVAL;
132 }
133
134 static __always_inline int
xdp_update_stats(struct xdp_md * xdp,bool tx,bool dut)135 xdp_update_stats(struct xdp_md *xdp, bool tx, bool dut)
136 {
137 __u32 *val, key = 0;
138
139 if (xdp_process_echo_packet(xdp, tx))
140 return -EINVAL;
141
142 if (dut)
143 val = bpf_map_lookup_elem(&dut_stats, &key);
144 else
145 val = bpf_map_lookup_elem(&stats, &key);
146
147 if (val)
148 __sync_add_and_fetch(val, 1);
149
150 return 0;
151 }
152
153 /* Tester */
154
155 SEC("xdp")
xdp_tester_check_tx(struct xdp_md * xdp)156 int xdp_tester_check_tx(struct xdp_md *xdp)
157 {
158 xdp_update_stats(xdp, true, false);
159
160 return XDP_PASS;
161 }
162
163 SEC("xdp")
xdp_tester_check_rx(struct xdp_md * xdp)164 int xdp_tester_check_rx(struct xdp_md *xdp)
165 {
166 xdp_update_stats(xdp, false, false);
167
168 return XDP_PASS;
169 }
170
171 /* DUT */
172
173 SEC("xdp")
xdp_do_pass(struct xdp_md * xdp)174 int xdp_do_pass(struct xdp_md *xdp)
175 {
176 xdp_update_stats(xdp, true, true);
177
178 return XDP_PASS;
179 }
180
181 SEC("xdp")
xdp_do_drop(struct xdp_md * xdp)182 int xdp_do_drop(struct xdp_md *xdp)
183 {
184 if (xdp_update_stats(xdp, true, true))
185 return XDP_PASS;
186
187 return XDP_DROP;
188 }
189
190 SEC("xdp")
xdp_do_aborted(struct xdp_md * xdp)191 int xdp_do_aborted(struct xdp_md *xdp)
192 {
193 if (xdp_process_echo_packet(xdp, true))
194 return XDP_PASS;
195
196 return XDP_ABORTED;
197 }
198
199 SEC("xdp")
xdp_do_tx(struct xdp_md * xdp)200 int xdp_do_tx(struct xdp_md *xdp)
201 {
202 void *data = (void *)(long)xdp->data;
203 struct ethhdr *eh = data;
204 __u8 tmp_mac[ETH_ALEN];
205
206 if (xdp_update_stats(xdp, true, true))
207 return XDP_PASS;
208
209 __builtin_memcpy(tmp_mac, eh->h_source, ETH_ALEN);
210 __builtin_memcpy(eh->h_source, eh->h_dest, ETH_ALEN);
211 __builtin_memcpy(eh->h_dest, tmp_mac, ETH_ALEN);
212
213 return XDP_TX;
214 }
215
216 SEC("xdp")
xdp_do_redirect(struct xdp_md * xdp)217 int xdp_do_redirect(struct xdp_md *xdp)
218 {
219 if (xdp_process_echo_packet(xdp, true))
220 return XDP_PASS;
221
222 return bpf_redirect_map(&cpu_map, 0, 0);
223 }
224
225 SEC("tp_btf/xdp_exception")
BPF_PROG(xdp_exception,const struct net_device * dev,const struct bpf_prog * xdp,__u32 act)226 int BPF_PROG(xdp_exception, const struct net_device *dev,
227 const struct bpf_prog *xdp, __u32 act)
228 {
229 __u32 *val, key = 0;
230
231 val = bpf_map_lookup_elem(&dut_stats, &key);
232 if (val)
233 __sync_add_and_fetch(val, 1);
234
235 return 0;
236 }
237
238 SEC("tp_btf/xdp_cpumap_kthread")
BPF_PROG(tp_xdp_cpumap_kthread,int map_id,unsigned int processed,unsigned int drops,int sched,struct xdp_cpumap_stats * xdp_stats)239 int BPF_PROG(tp_xdp_cpumap_kthread, int map_id, unsigned int processed,
240 unsigned int drops, int sched, struct xdp_cpumap_stats *xdp_stats)
241 {
242 __u32 *val, key = 0;
243
244 val = bpf_map_lookup_elem(&dut_stats, &key);
245 if (val)
246 __sync_add_and_fetch(val, 1);
247
248 return 0;
249 }
250
251 SEC("xdp/cpumap")
xdp_do_redirect_cpumap(struct xdp_md * xdp)252 int xdp_do_redirect_cpumap(struct xdp_md *xdp)
253 {
254 void *data = (void *)(long)xdp->data;
255 struct ethhdr *eh = data;
256 __u8 tmp_mac[ETH_ALEN];
257
258 if (xdp_process_echo_packet(xdp, true))
259 return XDP_PASS;
260
261 __builtin_memcpy(tmp_mac, eh->h_source, ETH_ALEN);
262 __builtin_memcpy(eh->h_source, eh->h_dest, ETH_ALEN);
263 __builtin_memcpy(eh->h_dest, tmp_mac, ETH_ALEN);
264
265 return bpf_redirect_map(&dev_map, 0, 0);
266 }
267
268 char _license[] SEC("license") = "GPL";
269