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 <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			/* use server program */
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		/* Only supports IPv4; see hints initiailization above. */
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	/* Start xdping-ing from last regular ping reply, e.g. for a count
220	 * of 10 ICMP requests, we start xdping-ing using reply with seq number
221	 * 10.  The reason the last "real" ping RTT is much higher is that
222	 * the ping program sees the ICMP reply associated with the last
223	 * XDP-generated packet, so ping doesn't get a reply until XDP is done.
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	/* We need to wait for XDP setup to complete. */
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