xref: /linux/samples/bpf/xdp_router_ipv4_user.c (revision da1d9caf95def6f0320819cf941c9fd1069ba9e1)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /* Copyright (C) 2017 Cavium, Inc.
3  */
4 #include <linux/bpf.h>
5 #include <linux/netlink.h>
6 #include <linux/rtnetlink.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 <sys/socket.h>
14 #include <unistd.h>
15 #include <bpf/bpf.h>
16 #include <arpa/inet.h>
17 #include <fcntl.h>
18 #include <poll.h>
19 #include <net/if.h>
20 #include <netdb.h>
21 #include <sys/ioctl.h>
22 #include <sys/syscall.h>
23 #include "bpf_util.h"
24 #include <bpf/libbpf.h>
25 #include <libgen.h>
26 #include <getopt.h>
27 #include <pthread.h>
28 #include "xdp_sample_user.h"
29 #include "xdp_router_ipv4.skel.h"
30 
31 static const char *__doc__ =
32 "XDP IPv4 router implementation\n"
33 "Usage: xdp_router_ipv4 <IFNAME-0> ... <IFNAME-N>\n";
34 
35 static char buf[8192];
36 static int lpm_map_fd;
37 static int arp_table_map_fd;
38 static int exact_match_map_fd;
39 static int tx_port_map_fd;
40 
41 static bool routes_thread_exit;
42 static int interval = 5;
43 
44 static int mask = SAMPLE_RX_CNT | SAMPLE_REDIRECT_ERR_MAP_CNT |
45 		  SAMPLE_DEVMAP_XMIT_CNT_MULTI | SAMPLE_EXCEPTION_CNT;
46 
47 DEFINE_SAMPLE_INIT(xdp_router_ipv4);
48 
49 static const struct option long_options[] = {
50 	{ "help", no_argument, NULL, 'h' },
51 	{ "skb-mode", no_argument, NULL, 'S' },
52 	{ "force", no_argument, NULL, 'F' },
53 	{ "interval", required_argument, NULL, 'i' },
54 	{ "verbose", no_argument, NULL, 'v' },
55 	{ "stats", no_argument, NULL, 's' },
56 	{}
57 };
58 
59 static int get_route_table(int rtm_family);
60 
61 static int recv_msg(struct sockaddr_nl sock_addr, int sock)
62 {
63 	struct nlmsghdr *nh;
64 	int len, nll = 0;
65 	char *buf_ptr;
66 
67 	buf_ptr = buf;
68 	while (1) {
69 		len = recv(sock, buf_ptr, sizeof(buf) - nll, 0);
70 		if (len < 0)
71 			return len;
72 
73 		nh = (struct nlmsghdr *)buf_ptr;
74 
75 		if (nh->nlmsg_type == NLMSG_DONE)
76 			break;
77 		buf_ptr += len;
78 		nll += len;
79 		if ((sock_addr.nl_groups & RTMGRP_NEIGH) == RTMGRP_NEIGH)
80 			break;
81 
82 		if ((sock_addr.nl_groups & RTMGRP_IPV4_ROUTE) == RTMGRP_IPV4_ROUTE)
83 			break;
84 	}
85 	return nll;
86 }
87 
88 /* Function to parse the route entry returned by netlink
89  * Updates the route entry related map entries
90  */
91 static void read_route(struct nlmsghdr *nh, int nll)
92 {
93 	char dsts[24], gws[24], ifs[16], dsts_len[24], metrics[24];
94 	struct bpf_lpm_trie_key *prefix_key;
95 	struct rtattr *rt_attr;
96 	struct rtmsg *rt_msg;
97 	int rtm_family;
98 	int rtl;
99 	int i;
100 	struct route_table {
101 		int  dst_len, iface, metric;
102 		__be32 dst, gw;
103 		__be64 mac;
104 	} route;
105 	struct arp_table {
106 		__be64 mac;
107 		__be32 dst;
108 	};
109 
110 	struct direct_map {
111 		struct arp_table arp;
112 		int ifindex;
113 		__be64 mac;
114 	} direct_entry;
115 
116 	memset(&route, 0, sizeof(route));
117 	for (; NLMSG_OK(nh, nll); nh = NLMSG_NEXT(nh, nll)) {
118 		rt_msg = (struct rtmsg *)NLMSG_DATA(nh);
119 		rtm_family = rt_msg->rtm_family;
120 		if (rtm_family == AF_INET)
121 			if (rt_msg->rtm_table != RT_TABLE_MAIN)
122 				continue;
123 		rt_attr = (struct rtattr *)RTM_RTA(rt_msg);
124 		rtl = RTM_PAYLOAD(nh);
125 
126 		for (; RTA_OK(rt_attr, rtl); rt_attr = RTA_NEXT(rt_attr, rtl)) {
127 			switch (rt_attr->rta_type) {
128 			case NDA_DST:
129 				sprintf(dsts, "%u",
130 					(*((__be32 *)RTA_DATA(rt_attr))));
131 				break;
132 			case RTA_GATEWAY:
133 				sprintf(gws, "%u",
134 					*((__be32 *)RTA_DATA(rt_attr)));
135 				break;
136 			case RTA_OIF:
137 				sprintf(ifs, "%u",
138 					*((int *)RTA_DATA(rt_attr)));
139 				break;
140 			case RTA_METRICS:
141 				sprintf(metrics, "%u",
142 					*((int *)RTA_DATA(rt_attr)));
143 			default:
144 				break;
145 			}
146 		}
147 		sprintf(dsts_len, "%d", rt_msg->rtm_dst_len);
148 		route.dst = atoi(dsts);
149 		route.dst_len = atoi(dsts_len);
150 		route.gw = atoi(gws);
151 		route.iface = atoi(ifs);
152 		route.metric = atoi(metrics);
153 		assert(get_mac_addr(route.iface, &route.mac) == 0);
154 		assert(bpf_map_update_elem(tx_port_map_fd,
155 					   &route.iface, &route.iface, 0) == 0);
156 		if (rtm_family == AF_INET) {
157 			struct trie_value {
158 				__u8 prefix[4];
159 				__be64 value;
160 				int ifindex;
161 				int metric;
162 				__be32 gw;
163 			} *prefix_value;
164 
165 			prefix_key = alloca(sizeof(*prefix_key) + 3);
166 			prefix_value = alloca(sizeof(*prefix_value));
167 
168 			prefix_key->prefixlen = 32;
169 			prefix_key->prefixlen = route.dst_len;
170 			direct_entry.mac = route.mac & 0xffffffffffff;
171 			direct_entry.ifindex = route.iface;
172 			direct_entry.arp.mac = 0;
173 			direct_entry.arp.dst = 0;
174 			if (route.dst_len == 32) {
175 				if (nh->nlmsg_type == RTM_DELROUTE) {
176 					assert(bpf_map_delete_elem(exact_match_map_fd,
177 								   &route.dst) == 0);
178 				} else {
179 					if (bpf_map_lookup_elem(arp_table_map_fd,
180 								&route.dst,
181 								&direct_entry.arp.mac) == 0)
182 						direct_entry.arp.dst = route.dst;
183 					assert(bpf_map_update_elem(exact_match_map_fd,
184 								   &route.dst,
185 								   &direct_entry, 0) == 0);
186 				}
187 			}
188 			for (i = 0; i < 4; i++)
189 				prefix_key->data[i] = (route.dst >> i * 8) & 0xff;
190 
191 			if (bpf_map_lookup_elem(lpm_map_fd, prefix_key,
192 						prefix_value) < 0) {
193 				for (i = 0; i < 4; i++)
194 					prefix_value->prefix[i] = prefix_key->data[i];
195 				prefix_value->value = route.mac & 0xffffffffffff;
196 				prefix_value->ifindex = route.iface;
197 				prefix_value->gw = route.gw;
198 				prefix_value->metric = route.metric;
199 
200 				assert(bpf_map_update_elem(lpm_map_fd,
201 							   prefix_key,
202 							   prefix_value, 0
203 							   ) == 0);
204 			} else {
205 				if (nh->nlmsg_type == RTM_DELROUTE) {
206 					assert(bpf_map_delete_elem(lpm_map_fd,
207 								   prefix_key
208 								   ) == 0);
209 					/* Rereading the route table to check if
210 					 * there is an entry with the same
211 					 * prefix but a different metric as the
212 					 * deleted enty.
213 					 */
214 					get_route_table(AF_INET);
215 				} else if (prefix_key->data[0] ==
216 					   prefix_value->prefix[0] &&
217 					   prefix_key->data[1] ==
218 					   prefix_value->prefix[1] &&
219 					   prefix_key->data[2] ==
220 					   prefix_value->prefix[2] &&
221 					   prefix_key->data[3] ==
222 					   prefix_value->prefix[3] &&
223 					   route.metric >= prefix_value->metric) {
224 					continue;
225 				} else {
226 					for (i = 0; i < 4; i++)
227 						prefix_value->prefix[i] =
228 							prefix_key->data[i];
229 					prefix_value->value =
230 						route.mac & 0xffffffffffff;
231 					prefix_value->ifindex = route.iface;
232 					prefix_value->gw = route.gw;
233 					prefix_value->metric = route.metric;
234 					assert(bpf_map_update_elem(lpm_map_fd,
235 								   prefix_key,
236 								   prefix_value,
237 								   0) == 0);
238 				}
239 			}
240 		}
241 		memset(&route, 0, sizeof(route));
242 		memset(dsts, 0, sizeof(dsts));
243 		memset(dsts_len, 0, sizeof(dsts_len));
244 		memset(gws, 0, sizeof(gws));
245 		memset(ifs, 0, sizeof(ifs));
246 		memset(&route, 0, sizeof(route));
247 	}
248 }
249 
250 /* Function to read the existing route table  when the process is launched*/
251 static int get_route_table(int rtm_family)
252 {
253 	struct sockaddr_nl sa;
254 	struct nlmsghdr *nh;
255 	int sock, seq = 0;
256 	struct msghdr msg;
257 	struct iovec iov;
258 	int ret = 0;
259 	int nll;
260 
261 	struct {
262 		struct nlmsghdr nl;
263 		struct rtmsg rt;
264 		char buf[8192];
265 	} req;
266 
267 	sock = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE);
268 	if (sock < 0) {
269 		fprintf(stderr, "open netlink socket: %s\n", strerror(errno));
270 		return -errno;
271 	}
272 	memset(&sa, 0, sizeof(sa));
273 	sa.nl_family = AF_NETLINK;
274 	if (bind(sock, (struct sockaddr *)&sa, sizeof(sa)) < 0) {
275 		fprintf(stderr, "bind netlink socket: %s\n", strerror(errno));
276 		ret = -errno;
277 		goto cleanup;
278 	}
279 	memset(&req, 0, sizeof(req));
280 	req.nl.nlmsg_len = NLMSG_LENGTH(sizeof(struct rtmsg));
281 	req.nl.nlmsg_flags = NLM_F_REQUEST | NLM_F_DUMP;
282 	req.nl.nlmsg_type = RTM_GETROUTE;
283 
284 	req.rt.rtm_family = rtm_family;
285 	req.rt.rtm_table = RT_TABLE_MAIN;
286 	req.nl.nlmsg_pid = 0;
287 	req.nl.nlmsg_seq = ++seq;
288 	memset(&msg, 0, sizeof(msg));
289 	iov.iov_base = (void *)&req.nl;
290 	iov.iov_len = req.nl.nlmsg_len;
291 	msg.msg_iov = &iov;
292 	msg.msg_iovlen = 1;
293 	ret = sendmsg(sock, &msg, 0);
294 	if (ret < 0) {
295 		fprintf(stderr, "send to netlink: %s\n", strerror(errno));
296 		ret = -errno;
297 		goto cleanup;
298 	}
299 	memset(buf, 0, sizeof(buf));
300 	nll = recv_msg(sa, sock);
301 	if (nll < 0) {
302 		fprintf(stderr, "recv from netlink: %s\n", strerror(nll));
303 		ret = nll;
304 		goto cleanup;
305 	}
306 	nh = (struct nlmsghdr *)buf;
307 	read_route(nh, nll);
308 cleanup:
309 	close(sock);
310 	return ret;
311 }
312 
313 /* Function to parse the arp entry returned by netlink
314  * Updates the arp entry related map entries
315  */
316 static void read_arp(struct nlmsghdr *nh, int nll)
317 {
318 	struct rtattr *rt_attr;
319 	char dsts[24], mac[24];
320 	struct ndmsg *rt_msg;
321 	int rtl, ndm_family;
322 
323 	struct arp_table {
324 		__be64 mac;
325 		__be32 dst;
326 	} arp_entry;
327 	struct direct_map {
328 		struct arp_table arp;
329 		int ifindex;
330 		__be64 mac;
331 	} direct_entry;
332 
333 	for (; NLMSG_OK(nh, nll); nh = NLMSG_NEXT(nh, nll)) {
334 		rt_msg = (struct ndmsg *)NLMSG_DATA(nh);
335 		rt_attr = (struct rtattr *)RTM_RTA(rt_msg);
336 		ndm_family = rt_msg->ndm_family;
337 		rtl = RTM_PAYLOAD(nh);
338 		for (; RTA_OK(rt_attr, rtl); rt_attr = RTA_NEXT(rt_attr, rtl)) {
339 			switch (rt_attr->rta_type) {
340 			case NDA_DST:
341 				sprintf(dsts, "%u",
342 					*((__be32 *)RTA_DATA(rt_attr)));
343 				break;
344 			case NDA_LLADDR:
345 				sprintf(mac, "%lld",
346 					*((__be64 *)RTA_DATA(rt_attr)));
347 				break;
348 			default:
349 				break;
350 			}
351 		}
352 		arp_entry.dst = atoi(dsts);
353 		arp_entry.mac = atol(mac);
354 
355 		if (ndm_family == AF_INET) {
356 			if (bpf_map_lookup_elem(exact_match_map_fd,
357 						&arp_entry.dst,
358 						&direct_entry) == 0) {
359 				if (nh->nlmsg_type == RTM_DELNEIGH) {
360 					direct_entry.arp.dst = 0;
361 					direct_entry.arp.mac = 0;
362 				} else if (nh->nlmsg_type == RTM_NEWNEIGH) {
363 					direct_entry.arp.dst = arp_entry.dst;
364 					direct_entry.arp.mac = arp_entry.mac;
365 				}
366 				assert(bpf_map_update_elem(exact_match_map_fd,
367 							   &arp_entry.dst,
368 							   &direct_entry, 0
369 							   ) == 0);
370 				memset(&direct_entry, 0, sizeof(direct_entry));
371 			}
372 			if (nh->nlmsg_type == RTM_DELNEIGH) {
373 				assert(bpf_map_delete_elem(arp_table_map_fd,
374 							   &arp_entry.dst) == 0);
375 			} else if (nh->nlmsg_type == RTM_NEWNEIGH) {
376 				assert(bpf_map_update_elem(arp_table_map_fd,
377 							   &arp_entry.dst,
378 							   &arp_entry.mac, 0
379 							   ) == 0);
380 			}
381 		}
382 		memset(&arp_entry, 0, sizeof(arp_entry));
383 		memset(dsts, 0, sizeof(dsts));
384 	}
385 }
386 
387 /* Function to read the existing arp table  when the process is launched*/
388 static int get_arp_table(int rtm_family)
389 {
390 	struct sockaddr_nl sa;
391 	struct nlmsghdr *nh;
392 	int sock, seq = 0;
393 	struct msghdr msg;
394 	struct iovec iov;
395 	int ret = 0;
396 	int nll;
397 	struct {
398 		struct nlmsghdr nl;
399 		struct ndmsg rt;
400 		char buf[8192];
401 	} req;
402 
403 	sock = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE);
404 	if (sock < 0) {
405 		fprintf(stderr, "open netlink socket: %s\n", strerror(errno));
406 		return -errno;
407 	}
408 	memset(&sa, 0, sizeof(sa));
409 	sa.nl_family = AF_NETLINK;
410 	if (bind(sock, (struct sockaddr *)&sa, sizeof(sa)) < 0) {
411 		fprintf(stderr, "bind netlink socket: %s\n", strerror(errno));
412 		ret = -errno;
413 		goto cleanup;
414 	}
415 	memset(&req, 0, sizeof(req));
416 	req.nl.nlmsg_len = NLMSG_LENGTH(sizeof(struct rtmsg));
417 	req.nl.nlmsg_flags = NLM_F_REQUEST | NLM_F_DUMP;
418 	req.nl.nlmsg_type = RTM_GETNEIGH;
419 	req.rt.ndm_state = NUD_REACHABLE;
420 	req.rt.ndm_family = rtm_family;
421 	req.nl.nlmsg_pid = 0;
422 	req.nl.nlmsg_seq = ++seq;
423 	memset(&msg, 0, sizeof(msg));
424 	iov.iov_base = (void *)&req.nl;
425 	iov.iov_len = req.nl.nlmsg_len;
426 	msg.msg_iov = &iov;
427 	msg.msg_iovlen = 1;
428 	ret = sendmsg(sock, &msg, 0);
429 	if (ret < 0) {
430 		fprintf(stderr, "send to netlink: %s\n", strerror(errno));
431 		ret = -errno;
432 		goto cleanup;
433 	}
434 	memset(buf, 0, sizeof(buf));
435 	nll = recv_msg(sa, sock);
436 	if (nll < 0) {
437 		fprintf(stderr, "recv from netlink: %s\n", strerror(nll));
438 		ret = nll;
439 		goto cleanup;
440 	}
441 	nh = (struct nlmsghdr *)buf;
442 	read_arp(nh, nll);
443 cleanup:
444 	close(sock);
445 	return ret;
446 }
447 
448 /* Function to keep track and update changes in route and arp table
449  * Give regular statistics of packets forwarded
450  */
451 static void *monitor_routes_thread(void *arg)
452 {
453 	struct pollfd fds_route, fds_arp;
454 	struct sockaddr_nl la, lr;
455 	int sock, sock_arp, nll;
456 	struct nlmsghdr *nh;
457 
458 	sock = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE);
459 	if (sock < 0) {
460 		fprintf(stderr, "open netlink socket: %s\n", strerror(errno));
461 		return NULL;
462 	}
463 
464 	fcntl(sock, F_SETFL, O_NONBLOCK);
465 	memset(&lr, 0, sizeof(lr));
466 	lr.nl_family = AF_NETLINK;
467 	lr.nl_groups = RTMGRP_IPV6_ROUTE | RTMGRP_IPV4_ROUTE | RTMGRP_NOTIFY;
468 	if (bind(sock, (struct sockaddr *)&lr, sizeof(lr)) < 0) {
469 		fprintf(stderr, "bind netlink socket: %s\n", strerror(errno));
470 		close(sock);
471 		return NULL;
472 	}
473 
474 	fds_route.fd = sock;
475 	fds_route.events = POLL_IN;
476 
477 	sock_arp = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE);
478 	if (sock_arp < 0) {
479 		fprintf(stderr, "open netlink socket: %s\n", strerror(errno));
480 		close(sock);
481 		return NULL;
482 	}
483 
484 	fcntl(sock_arp, F_SETFL, O_NONBLOCK);
485 	memset(&la, 0, sizeof(la));
486 	la.nl_family = AF_NETLINK;
487 	la.nl_groups = RTMGRP_NEIGH | RTMGRP_NOTIFY;
488 	if (bind(sock_arp, (struct sockaddr *)&la, sizeof(la)) < 0) {
489 		fprintf(stderr, "bind netlink socket: %s\n", strerror(errno));
490 		goto cleanup;
491 	}
492 
493 	fds_arp.fd = sock_arp;
494 	fds_arp.events = POLL_IN;
495 
496 	/* dump route and arp tables */
497 	if (get_arp_table(AF_INET) < 0) {
498 		fprintf(stderr, "Failed reading arp table\n");
499 		goto cleanup;
500 	}
501 
502 	if (get_route_table(AF_INET) < 0) {
503 		fprintf(stderr, "Failed reading route table\n");
504 		goto cleanup;
505 	}
506 
507 	while (!routes_thread_exit) {
508 		memset(buf, 0, sizeof(buf));
509 		if (poll(&fds_route, 1, 3) == POLL_IN) {
510 			nll = recv_msg(lr, sock);
511 			if (nll < 0) {
512 				fprintf(stderr, "recv from netlink: %s\n",
513 					strerror(nll));
514 				goto cleanup;
515 			}
516 
517 			nh = (struct nlmsghdr *)buf;
518 			read_route(nh, nll);
519 		}
520 
521 		memset(buf, 0, sizeof(buf));
522 		if (poll(&fds_arp, 1, 3) == POLL_IN) {
523 			nll = recv_msg(la, sock_arp);
524 			if (nll < 0) {
525 				fprintf(stderr, "recv from netlink: %s\n",
526 					strerror(nll));
527 				goto cleanup;
528 			}
529 
530 			nh = (struct nlmsghdr *)buf;
531 			read_arp(nh, nll);
532 		}
533 
534 		sleep(interval);
535 	}
536 
537 cleanup:
538 	close(sock_arp);
539 	close(sock);
540 	return NULL;
541 }
542 
543 static void usage(char *argv[], const struct option *long_options,
544 		  const char *doc, int mask, bool error,
545 		  struct bpf_object *obj)
546 {
547 	sample_usage(argv, long_options, doc, mask, error);
548 }
549 
550 int main(int argc, char **argv)
551 {
552 	bool error = true, generic = false, force = false;
553 	int opt, ret = EXIT_FAIL_BPF;
554 	struct xdp_router_ipv4 *skel;
555 	int i, total_ifindex = argc - 1;
556 	char **ifname_list = argv + 1;
557 	pthread_t routes_thread;
558 	int longindex = 0;
559 
560 	if (libbpf_set_strict_mode(LIBBPF_STRICT_ALL) < 0) {
561 		fprintf(stderr, "Failed to set libbpf strict mode: %s\n",
562 			strerror(errno));
563 		goto end;
564 	}
565 
566 	skel = xdp_router_ipv4__open();
567 	if (!skel) {
568 		fprintf(stderr, "Failed to xdp_router_ipv4__open: %s\n",
569 			strerror(errno));
570 		goto end;
571 	}
572 
573 	ret = sample_init_pre_load(skel);
574 	if (ret < 0) {
575 		fprintf(stderr, "Failed to sample_init_pre_load: %s\n",
576 			strerror(-ret));
577 		ret = EXIT_FAIL_BPF;
578 		goto end_destroy;
579 	}
580 
581 	ret = xdp_router_ipv4__load(skel);
582 	if (ret < 0) {
583 		fprintf(stderr, "Failed to xdp_router_ipv4__load: %s\n",
584 			strerror(errno));
585 		goto end_destroy;
586 	}
587 
588 	ret = sample_init(skel, mask);
589 	if (ret < 0) {
590 		fprintf(stderr, "Failed to initialize sample: %s\n", strerror(-ret));
591 		ret = EXIT_FAIL;
592 		goto end_destroy;
593 	}
594 
595 	while ((opt = getopt_long(argc, argv, "si:SFvh",
596 				  long_options, &longindex)) != -1) {
597 		switch (opt) {
598 		case 's':
599 			mask |= SAMPLE_REDIRECT_MAP_CNT;
600 			total_ifindex--;
601 			ifname_list++;
602 			break;
603 		case 'i':
604 			interval = strtoul(optarg, NULL, 0);
605 			total_ifindex -= 2;
606 			ifname_list += 2;
607 			break;
608 		case 'S':
609 			generic = true;
610 			total_ifindex--;
611 			ifname_list++;
612 			break;
613 		case 'F':
614 			force = true;
615 			total_ifindex--;
616 			ifname_list++;
617 			break;
618 		case 'v':
619 			sample_switch_mode();
620 			total_ifindex--;
621 			ifname_list++;
622 			break;
623 		case 'h':
624 			error = false;
625 		default:
626 			usage(argv, long_options, __doc__, mask, error, skel->obj);
627 			goto end_destroy;
628 		}
629 	}
630 
631 	ret = EXIT_FAIL_OPTION;
632 	if (optind == argc) {
633 		usage(argv, long_options, __doc__, mask, true, skel->obj);
634 		goto end_destroy;
635 	}
636 
637 	lpm_map_fd = bpf_map__fd(skel->maps.lpm_map);
638 	if (lpm_map_fd < 0) {
639 		fprintf(stderr, "Failed loading lpm_map %s\n",
640 			strerror(-lpm_map_fd));
641 		goto end_destroy;
642 	}
643 	arp_table_map_fd = bpf_map__fd(skel->maps.arp_table);
644 	if (arp_table_map_fd < 0) {
645 		fprintf(stderr, "Failed loading arp_table_map_fd %s\n",
646 			strerror(-arp_table_map_fd));
647 		goto end_destroy;
648 	}
649 	exact_match_map_fd = bpf_map__fd(skel->maps.exact_match);
650 	if (exact_match_map_fd < 0) {
651 		fprintf(stderr, "Failed loading exact_match_map_fd %s\n",
652 			strerror(-exact_match_map_fd));
653 		goto end_destroy;
654 	}
655 	tx_port_map_fd = bpf_map__fd(skel->maps.tx_port);
656 	if (tx_port_map_fd < 0) {
657 		fprintf(stderr, "Failed loading tx_port_map_fd %s\n",
658 			strerror(-tx_port_map_fd));
659 		goto end_destroy;
660 	}
661 
662 	ret = EXIT_FAIL_XDP;
663 	for (i = 0; i < total_ifindex; i++) {
664 		int index = if_nametoindex(ifname_list[i]);
665 
666 		if (!index) {
667 			fprintf(stderr, "Interface %s not found %s\n",
668 				ifname_list[i], strerror(-tx_port_map_fd));
669 			goto end_destroy;
670 		}
671 		if (sample_install_xdp(skel->progs.xdp_router_ipv4_prog,
672 				       index, generic, force) < 0)
673 			goto end_destroy;
674 	}
675 
676 	ret = pthread_create(&routes_thread, NULL, monitor_routes_thread, NULL);
677 	if (ret) {
678 		fprintf(stderr, "Failed creating routes_thread: %s\n", strerror(-ret));
679 		ret = EXIT_FAIL;
680 		goto end_destroy;
681 	}
682 
683 	ret = sample_run(interval, NULL, NULL);
684 	routes_thread_exit = true;
685 
686 	if (ret < 0) {
687 		fprintf(stderr, "Failed during sample run: %s\n", strerror(-ret));
688 		ret = EXIT_FAIL;
689 		goto end_thread_wait;
690 	}
691 	ret = EXIT_OK;
692 
693 end_thread_wait:
694 	pthread_join(routes_thread, NULL);
695 end_destroy:
696 	xdp_router_ipv4__destroy(skel);
697 end:
698 	sample_exit(ret);
699 }
700