1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright (c) 2019, Oracle and/or its affiliates. All rights reserved. */
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 <net/if.h>
16 #include <sys/types.h>
17 #include <sys/socket.h>
18 #include <netdb.h>
19 
20 #include "bpf/bpf.h"
21 #include "bpf/libbpf.h"
22 
23 #include "xdping.h"
24 #include "testing_helpers.h"
25 
26 static int ifindex;
27 static __u32 xdp_flags = XDP_FLAGS_UPDATE_IF_NOEXIST;
28 
29 static void cleanup(int sig)
30 {
31 	bpf_xdp_detach(ifindex, xdp_flags, NULL);
32 	if (sig)
33 		exit(1);
34 }
35 
36 static 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 
73 static 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 
87 int 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 	__u16 count = XDPING_DEFAULT_COUNT;
92 	struct pinginfo pinginfo = { 0 };
93 	const char *optstr = "c:I:NsS";
94 	struct bpf_program *main_prog;
95 	int prog_fd = -1, map_fd = -1;
96 	struct sockaddr_in rin;
97 	struct bpf_object *obj;
98 	struct bpf_map *map;
99 	char *ifname = NULL;
100 	char filename[256];
101 	int opt, ret = 1;
102 	__u32 raddr = 0;
103 	int server = 0;
104 	char cmd[256];
105 
106 	while ((opt = getopt(argc, argv, optstr)) != -1) {
107 		switch (opt) {
108 		case 'c':
109 			count = atoi(optarg);
110 			if (count < 1 || count > XDPING_MAX_COUNT) {
111 				fprintf(stderr,
112 					"min count is 1, max count is %d\n",
113 					XDPING_MAX_COUNT);
114 				return 1;
115 			}
116 			break;
117 		case 'I':
118 			ifname = optarg;
119 			ifindex = if_nametoindex(ifname);
120 			if (!ifindex) {
121 				fprintf(stderr, "Could not get interface %s\n",
122 					ifname);
123 				return 1;
124 			}
125 			break;
126 		case 'N':
127 			xdp_flags |= XDP_FLAGS_DRV_MODE;
128 			break;
129 		case 's':
130 			/* use server program */
131 			server = 1;
132 			break;
133 		case 'S':
134 			xdp_flags |= XDP_FLAGS_SKB_MODE;
135 			break;
136 		default:
137 			show_usage(basename(argv[0]));
138 			return 1;
139 		}
140 	}
141 
142 	if (!ifname) {
143 		show_usage(basename(argv[0]));
144 		return 1;
145 	}
146 	if (!server && optind == argc) {
147 		show_usage(basename(argv[0]));
148 		return 1;
149 	}
150 
151 	if ((xdp_flags & mode_flags) == mode_flags) {
152 		fprintf(stderr, "-N or -S can be specified, not both.\n");
153 		show_usage(basename(argv[0]));
154 		return 1;
155 	}
156 
157 	if (!server) {
158 		/* Only supports IPv4; see hints initiailization above. */
159 		if (getaddrinfo(argv[optind], NULL, &hints, &a) || !a) {
160 			fprintf(stderr, "Could not resolve %s\n", argv[optind]);
161 			return 1;
162 		}
163 		memcpy(&rin, a->ai_addr, sizeof(rin));
164 		raddr = rin.sin_addr.s_addr;
165 		freeaddrinfo(a);
166 	}
167 
168 	/* Use libbpf 1.0 API mode */
169 	libbpf_set_strict_mode(LIBBPF_STRICT_ALL);
170 
171 	snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
172 
173 	if (bpf_prog_test_load(filename, BPF_PROG_TYPE_XDP, &obj, &prog_fd)) {
174 		fprintf(stderr, "load of %s failed\n", filename);
175 		return 1;
176 	}
177 
178 	main_prog = bpf_object__find_program_by_name(obj,
179 						     server ? "xdping_server" : "xdping_client");
180 	if (main_prog)
181 		prog_fd = bpf_program__fd(main_prog);
182 	if (!main_prog || prog_fd < 0) {
183 		fprintf(stderr, "could not find xdping program");
184 		return 1;
185 	}
186 
187 	map = bpf_object__next_map(obj, NULL);
188 	if (map)
189 		map_fd = bpf_map__fd(map);
190 	if (!map || map_fd < 0) {
191 		fprintf(stderr, "Could not find ping map");
192 		goto done;
193 	}
194 
195 	signal(SIGINT, cleanup);
196 	signal(SIGTERM, cleanup);
197 
198 	printf("Setting up XDP for %s, please wait...\n", ifname);
199 
200 	printf("XDP setup disrupts network connectivity, hit Ctrl+C to quit\n");
201 
202 	if (bpf_xdp_attach(ifindex, prog_fd, xdp_flags, NULL) < 0) {
203 		fprintf(stderr, "Link set xdp fd failed for %s\n", ifname);
204 		goto done;
205 	}
206 
207 	if (server) {
208 		close(prog_fd);
209 		close(map_fd);
210 		printf("Running server on %s; press Ctrl+C to exit...\n",
211 		       ifname);
212 		do { } while (1);
213 	}
214 
215 	/* Start xdping-ing from last regular ping reply, e.g. for a count
216 	 * of 10 ICMP requests, we start xdping-ing using reply with seq number
217 	 * 10.  The reason the last "real" ping RTT is much higher is that
218 	 * the ping program sees the ICMP reply associated with the last
219 	 * XDP-generated packet, so ping doesn't get a reply until XDP is done.
220 	 */
221 	pinginfo.seq = htons(count);
222 	pinginfo.count = count;
223 
224 	if (bpf_map_update_elem(map_fd, &raddr, &pinginfo, BPF_ANY)) {
225 		fprintf(stderr, "could not communicate with BPF map: %s\n",
226 			strerror(errno));
227 		cleanup(0);
228 		goto done;
229 	}
230 
231 	/* We need to wait for XDP setup to complete. */
232 	sleep(10);
233 
234 	snprintf(cmd, sizeof(cmd), "ping -c %d -I %s %s",
235 		 count, ifname, argv[optind]);
236 
237 	printf("\nNormal ping RTT data\n");
238 	printf("[Ignore final RTT; it is distorted by XDP using the reply]\n");
239 
240 	ret = system(cmd);
241 
242 	if (!ret)
243 		ret = get_stats(map_fd, count, raddr);
244 
245 	cleanup(0);
246 
247 done:
248 	if (prog_fd > 0)
249 		close(prog_fd);
250 	if (map_fd > 0)
251 		close(map_fd);
252 
253 	return ret;
254 }
255