1
2
3
4#include <linux/bpf.h>
5#include <linux/if_link.h>
6#include <arpa/inet.h>
7#include <assert.h>
8#include <errno.h>
9#include <signal.h>
10#include <stdio.h>
11#include <stdlib.h>
12#include <string.h>
13#include <unistd.h>
14#include <libgen.h>
15#include <sys/resource.h>
16#include <net/if.h>
17#include <sys/types.h>
18#include <sys/socket.h>
19#include <netdb.h>
20
21#include "bpf/bpf.h"
22#include "bpf/libbpf.h"
23
24#include "xdping.h"
25
26static int ifindex;
27static __u32 xdp_flags = XDP_FLAGS_UPDATE_IF_NOEXIST;
28
29static void cleanup(int sig)
30{
31 bpf_set_link_xdp_fd(ifindex, -1, xdp_flags);
32 if (sig)
33 exit(1);
34}
35
36static int get_stats(int fd, __u16 count, __u32 raddr)
37{
38 struct pinginfo pinginfo = { 0 };
39 char inaddrbuf[INET_ADDRSTRLEN];
40 struct in_addr inaddr;
41 __u16 i;
42
43 inaddr.s_addr = raddr;
44
45 printf("\nXDP RTT data:\n");
46
47 if (bpf_map_lookup_elem(fd, &raddr, &pinginfo)) {
48 perror("bpf_map_lookup elem");
49 return 1;
50 }
51
52 for (i = 0; i < count; i++) {
53 if (pinginfo.times[i] == 0)
54 break;
55
56 printf("64 bytes from %s: icmp_seq=%d ttl=64 time=%#.5f ms\n",
57 inet_ntop(AF_INET, &inaddr, inaddrbuf,
58 sizeof(inaddrbuf)),
59 count + i + 1,
60 (double)pinginfo.times[i]/1000000);
61 }
62
63 if (i < count) {
64 fprintf(stderr, "Expected %d samples, got %d.\n", count, i);
65 return 1;
66 }
67
68 bpf_map_delete_elem(fd, &raddr);
69
70 return 0;
71}
72
73static void show_usage(const char *prog)
74{
75 fprintf(stderr,
76 "usage: %s [OPTS] -I interface destination\n\n"
77 "OPTS:\n"
78 " -c count Stop after sending count requests\n"
79 " (default %d, max %d)\n"
80 " -I interface interface name\n"
81 " -N Run in driver mode\n"
82 " -s Server mode\n"
83 " -S Run in skb mode\n",
84 prog, XDPING_DEFAULT_COUNT, XDPING_MAX_COUNT);
85}
86
87int main(int argc, char **argv)
88{
89 __u32 mode_flags = XDP_FLAGS_DRV_MODE | XDP_FLAGS_SKB_MODE;
90 struct addrinfo *a, hints = { .ai_family = AF_INET };
91 struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
92 __u16 count = XDPING_DEFAULT_COUNT;
93 struct pinginfo pinginfo = { 0 };
94 const char *optstr = "c:I:NsS";
95 struct bpf_program *main_prog;
96 int prog_fd = -1, map_fd = -1;
97 struct sockaddr_in rin;
98 struct bpf_object *obj;
99 struct bpf_map *map;
100 char *ifname = NULL;
101 char filename[256];
102 int opt, ret = 1;
103 __u32 raddr = 0;
104 int server = 0;
105 char cmd[256];
106
107 while ((opt = getopt(argc, argv, optstr)) != -1) {
108 switch (opt) {
109 case 'c':
110 count = atoi(optarg);
111 if (count < 1 || count > XDPING_MAX_COUNT) {
112 fprintf(stderr,
113 "min count is 1, max count is %d\n",
114 XDPING_MAX_COUNT);
115 return 1;
116 }
117 break;
118 case 'I':
119 ifname = optarg;
120 ifindex = if_nametoindex(ifname);
121 if (!ifindex) {
122 fprintf(stderr, "Could not get interface %s\n",
123 ifname);
124 return 1;
125 }
126 break;
127 case 'N':
128 xdp_flags |= XDP_FLAGS_DRV_MODE;
129 break;
130 case 's':
131
132 server = 1;
133 break;
134 case 'S':
135 xdp_flags |= XDP_FLAGS_SKB_MODE;
136 break;
137 default:
138 show_usage(basename(argv[0]));
139 return 1;
140 }
141 }
142
143 if (!ifname) {
144 show_usage(basename(argv[0]));
145 return 1;
146 }
147 if (!server && optind == argc) {
148 show_usage(basename(argv[0]));
149 return 1;
150 }
151
152 if ((xdp_flags & mode_flags) == mode_flags) {
153 fprintf(stderr, "-N or -S can be specified, not both.\n");
154 show_usage(basename(argv[0]));
155 return 1;
156 }
157
158 if (!server) {
159
160 if (getaddrinfo(argv[optind], NULL, &hints, &a) || !a) {
161 fprintf(stderr, "Could not resolve %s\n", argv[optind]);
162 return 1;
163 }
164 memcpy(&rin, a->ai_addr, sizeof(rin));
165 raddr = rin.sin_addr.s_addr;
166 freeaddrinfo(a);
167 }
168
169 if (setrlimit(RLIMIT_MEMLOCK, &r)) {
170 perror("setrlimit(RLIMIT_MEMLOCK)");
171 return 1;
172 }
173
174 snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
175
176 if (bpf_prog_load(filename, BPF_PROG_TYPE_XDP, &obj, &prog_fd)) {
177 fprintf(stderr, "load of %s failed\n", filename);
178 return 1;
179 }
180
181 main_prog = bpf_object__find_program_by_title(obj,
182 server ? "xdpserver" :
183 "xdpclient");
184 if (main_prog)
185 prog_fd = bpf_program__fd(main_prog);
186 if (!main_prog || prog_fd < 0) {
187 fprintf(stderr, "could not find xdping program");
188 return 1;
189 }
190
191 map = bpf_map__next(NULL, obj);
192 if (map)
193 map_fd = bpf_map__fd(map);
194 if (!map || map_fd < 0) {
195 fprintf(stderr, "Could not find ping map");
196 goto done;
197 }
198
199 signal(SIGINT, cleanup);
200 signal(SIGTERM, cleanup);
201
202 printf("Setting up XDP for %s, please wait...\n", ifname);
203
204 printf("XDP setup disrupts network connectivity, hit Ctrl+C to quit\n");
205
206 if (bpf_set_link_xdp_fd(ifindex, prog_fd, xdp_flags) < 0) {
207 fprintf(stderr, "Link set xdp fd failed for %s\n", ifname);
208 goto done;
209 }
210
211 if (server) {
212 close(prog_fd);
213 close(map_fd);
214 printf("Running server on %s; press Ctrl+C to exit...\n",
215 ifname);
216 do { } while (1);
217 }
218
219
220
221
222
223
224
225 pinginfo.seq = htons(count);
226 pinginfo.count = count;
227
228 if (bpf_map_update_elem(map_fd, &raddr, &pinginfo, BPF_ANY)) {
229 fprintf(stderr, "could not communicate with BPF map: %s\n",
230 strerror(errno));
231 cleanup(0);
232 goto done;
233 }
234
235
236 sleep(10);
237
238 snprintf(cmd, sizeof(cmd), "ping -c %d -I %s %s",
239 count, ifname, argv[optind]);
240
241 printf("\nNormal ping RTT data\n");
242 printf("[Ignore final RTT; it is distorted by XDP using the reply]\n");
243
244 ret = system(cmd);
245
246 if (!ret)
247 ret = get_stats(map_fd, count, raddr);
248
249 cleanup(0);
250
251done:
252 if (prog_fd > 0)
253 close(prog_fd);
254 if (map_fd > 0)
255 close(map_fd);
256
257 return ret;
258}
259
