aboutsummaryrefslogtreecommitdiffstatshomepage
path: root/samples/bpf/xdp_tx_iptunnel_user.c
blob: a419bee151a85c60ded0a55943a2a6da43f38080 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
// SPDX-License-Identifier: GPL-2.0-only
/* Copyright (c) 2016 Facebook
 */
#include <linux/bpf.h>
#include <linux/if_link.h>
#include <assert.h>
#include <errno.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <net/if.h>
#include <sys/resource.h>
#include <arpa/inet.h>
#include <netinet/ether.h>
#include <unistd.h>
#include <time.h>
#include <bpf/libbpf.h>
#include <bpf/bpf.h>
#include "bpf_util.h"
#include "xdp_tx_iptunnel_common.h"

#define STATS_INTERVAL_S 2U

static int ifindex = -1;
static __u32 xdp_flags = XDP_FLAGS_UPDATE_IF_NOEXIST;
static int rxcnt_map_fd;
static __u32 prog_id;

static void int_exit(int sig)
{
	__u32 curr_prog_id = 0;

	if (ifindex > -1) {
		if (bpf_get_link_xdp_id(ifindex, &curr_prog_id, xdp_flags)) {
			printf("bpf_get_link_xdp_id failed\n");
			exit(1);
		}
		if (prog_id == curr_prog_id)
			bpf_set_link_xdp_fd(ifindex, -1, xdp_flags);
		else if (!curr_prog_id)
			printf("couldn't find a prog id on a given iface\n");
		else
			printf("program on interface changed, not removing\n");
	}
	exit(0);
}

/* simple per-protocol drop counter
 */
static void poll_stats(unsigned int kill_after_s)
{
	const unsigned int nr_protos = 256;
	unsigned int nr_cpus = bpf_num_possible_cpus();
	time_t started_at = time(NULL);
	__u64 values[nr_cpus], prev[nr_protos][nr_cpus];
	__u32 proto;
	int i;

	memset(prev, 0, sizeof(prev));

	while (!kill_after_s || time(NULL) - started_at <= kill_after_s) {
		sleep(STATS_INTERVAL_S);

		for (proto = 0; proto < nr_protos; proto++) {
			__u64 sum = 0;

			assert(bpf_map_lookup_elem(rxcnt_map_fd, &proto,
						   values) == 0);
			for (i = 0; i < nr_cpus; i++)
				sum += (values[i] - prev[proto][i]);

			if (sum)
				printf("proto %u: sum:%10llu pkts, rate:%10llu pkts/s\n",
				       proto, sum, sum / STATS_INTERVAL_S);
			memcpy(prev[proto], values, sizeof(values));
		}
	}
}

static void usage(const char *cmd)
{
	printf("Start a XDP prog which encapsulates incoming packets\n"
	       "in an IPv4/v6 header and XDP_TX it out.  The dst <VIP:PORT>\n"
	       "is used to select packets to encapsulate\n\n");
	printf("Usage: %s [...]\n", cmd);
	printf("    -i <ifname|ifindex> Interface\n");
	printf("    -a <vip-service-address> IPv4 or IPv6\n");
	printf("    -p <vip-service-port> A port range (e.g. 433-444) is also allowed\n");
	printf("    -s <source-ip> Used in the IPTunnel header\n");
	printf("    -d <dest-ip> Used in the IPTunnel header\n");
	printf("    -m <dest-MAC> Used in sending the IP Tunneled pkt\n");
	printf("    -T <stop-after-X-seconds> Default: 0 (forever)\n");
	printf("    -P <IP-Protocol> Default is TCP\n");
	printf("    -S use skb-mode\n");
	printf("    -N enforce native mode\n");
	printf("    -F Force loading the XDP prog\n");
	printf("    -h Display this help\n");
}

static int parse_ipstr(const char *ipstr, unsigned int *addr)
{
	if (inet_pton(AF_INET6, ipstr, addr) == 1) {
		return AF_INET6;
	} else if (inet_pton(AF_INET, ipstr, addr) == 1) {
		addr[1] = addr[2] = addr[3] = 0;
		return AF_INET;
	}

	fprintf(stderr, "%s is an invalid IP\n", ipstr);
	return AF_UNSPEC;
}

static int parse_ports(const char *port_str, int *min_port, int *max_port)
{
	char *end;
	long tmp_min_port;
	long tmp_max_port;

	tmp_min_port = strtol(optarg, &end, 10);
	if (tmp_min_port < 1 || tmp_min_port > 65535) {
		fprintf(stderr, "Invalid port(s):%s\n", optarg);
		return 1;
	}

	if (*end == '-') {
		end++;
		tmp_max_port = strtol(end, NULL, 10);
		if (tmp_max_port < 1 || tmp_max_port > 65535) {
			fprintf(stderr, "Invalid port(s):%s\n", optarg);
			return 1;
		}
	} else {
		tmp_max_port = tmp_min_port;
	}

	if (tmp_min_port > tmp_max_port) {
		fprintf(stderr, "Invalid port(s):%s\n", optarg);
		return 1;
	}

	if (tmp_max_port - tmp_min_port + 1 > MAX_IPTNL_ENTRIES) {
		fprintf(stderr, "Port range (%s) is larger than %u\n",
			port_str, MAX_IPTNL_ENTRIES);
		return 1;
	}
	*min_port = tmp_min_port;
	*max_port = tmp_max_port;

	return 0;
}

int main(int argc, char **argv)
{
	struct bpf_prog_load_attr prog_load_attr = {
		.prog_type	= BPF_PROG_TYPE_XDP,
	};
	struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
	int min_port = 0, max_port = 0, vip2tnl_map_fd;
	const char *optstr = "i:a:p:s:d:m:T:P:FSNh";
	unsigned char opt_flags[256] = {};
	struct bpf_prog_info info = {};
	__u32 info_len = sizeof(info);
	unsigned int kill_after_s = 0;
	struct iptnl_info tnl = {};
	struct bpf_object *obj;
	struct vip vip = {};
	char filename[256];
	int opt, prog_fd;
	int i, err;

	tnl.family = AF_UNSPEC;
	vip.protocol = IPPROTO_TCP;

	for (i = 0; i < strlen(optstr); i++)
		if (optstr[i] != 'h' && 'a' <= optstr[i] && optstr[i] <= 'z')
			opt_flags[(unsigned char)optstr[i]] = 1;

	while ((opt = getopt(argc, argv, optstr)) != -1) {
		unsigned short family;
		unsigned int *v6;

		switch (opt) {
		case 'i':
			ifindex = if_nametoindex(optarg);
			if (!ifindex)
				ifindex = atoi(optarg);
			break;
		case 'a':
			vip.family = parse_ipstr(optarg, vip.daddr.v6);
			if (vip.family == AF_UNSPEC)
				return 1;
			break;
		case 'p':
			if (parse_ports(optarg, &min_port, &max_port))
				return 1;
			break;
		case 'P':
			vip.protocol = atoi(optarg);
			break;
		case 's':
		case 'd':
			if (opt == 's')
				v6 = tnl.saddr.v6;
			else
				v6 = tnl.daddr.v6;

			family = parse_ipstr(optarg, v6);
			if (family == AF_UNSPEC)
				return 1;
			if (tnl.family == AF_UNSPEC) {
				tnl.family = family;
			} else if (tnl.family != family) {
				fprintf(stderr,
					"The IP version of the src and dst addresses used in the IP encapsulation does not match\n");
				return 1;
			}
			break;
		case 'm':
			if (!ether_aton_r(optarg,
					  (struct ether_addr *)tnl.dmac)) {
				fprintf(stderr, "Invalid mac address:%s\n",
					optarg);
				return 1;
			}
			break;
		case 'T':
			kill_after_s = atoi(optarg);
			break;
		case 'S':
			xdp_flags |= XDP_FLAGS_SKB_MODE;
			break;
		case 'N':
			/* default, set below */
			break;
		case 'F':
			xdp_flags &= ~XDP_FLAGS_UPDATE_IF_NOEXIST;
			break;
		default:
			usage(argv[0]);
			return 1;
		}
		opt_flags[opt] = 0;
	}

	if (!(xdp_flags & XDP_FLAGS_SKB_MODE))
		xdp_flags |= XDP_FLAGS_DRV_MODE;

	for (i = 0; i < strlen(optstr); i++) {
		if (opt_flags[(unsigned int)optstr[i]]) {
			fprintf(stderr, "Missing argument -%c\n", optstr[i]);
			usage(argv[0]);
			return 1;
		}
	}

	if (setrlimit(RLIMIT_MEMLOCK, &r)) {
		perror("setrlimit(RLIMIT_MEMLOCK, RLIM_INFINITY)");
		return 1;
	}

	if (!ifindex) {
		fprintf(stderr, "Invalid ifname\n");
		return 1;
	}

	snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
	prog_load_attr.file = filename;

	if (bpf_prog_load_xattr(&prog_load_attr, &obj, &prog_fd))
		return 1;

	if (!prog_fd) {
		printf("bpf_prog_load_xattr: %s\n", strerror(errno));
		return 1;
	}

	rxcnt_map_fd = bpf_object__find_map_fd_by_name(obj, "rxcnt");
	vip2tnl_map_fd = bpf_object__find_map_fd_by_name(obj, "vip2tnl");
	if (vip2tnl_map_fd < 0 || rxcnt_map_fd < 0) {
		printf("bpf_object__find_map_fd_by_name failed\n");
		return 1;
	}

	signal(SIGINT, int_exit);
	signal(SIGTERM, int_exit);

	while (min_port <= max_port) {
		vip.dport = htons(min_port++);
		if (bpf_map_update_elem(vip2tnl_map_fd, &vip, &tnl,
					BPF_NOEXIST)) {
			perror("bpf_map_update_elem(&vip2tnl)");
			return 1;
		}
	}

	if (bpf_set_link_xdp_fd(ifindex, prog_fd, xdp_flags) < 0) {
		printf("link set xdp fd failed\n");
		return 1;
	}

	err = bpf_obj_get_info_by_fd(prog_fd, &info, &info_len);
	if (err) {
		printf("can't get prog info - %s\n", strerror(errno));
		return err;
	}
	prog_id = info.id;

	poll_stats(kill_after_s);

	bpf_set_link_xdp_fd(ifindex, -1, xdp_flags);

	return 0;
}