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
26static int ifindex;
27static __u32 xdp_flags = XDP_FLAGS_UPDATE_IF_NOEXIST;
28
29static void cleanup(int sig)
30{
31	bpf_xdp_detach(ifindex, xdp_flags, NULL);
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	__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.bpf.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
247done:
248	if (prog_fd > 0)
249		close(prog_fd);
250	if (map_fd > 0)
251		close(map_fd);
252
253	return ret;
254}
255