1 // SPDX-License-Identifier: GPL-2.0
2 
3 #define _GNU_SOURCE
4 
5 #include <stddef.h>
6 #include <arpa/inet.h>
7 #include <error.h>
8 #include <errno.h>
9 #include <net/if.h>
10 #include <linux/in.h>
11 #include <linux/netlink.h>
12 #include <linux/rtnetlink.h>
13 #include <netinet/if_ether.h>
14 #include <netinet/ip.h>
15 #include <netinet/ip6.h>
16 #include <netinet/udp.h>
17 #include <stdbool.h>
18 #include <stdlib.h>
19 #include <stdio.h>
20 #include <string.h>
21 #include <sys/ioctl.h>
22 #include <sys/socket.h>
23 #include <sys/stat.h>
24 #include <sys/time.h>
25 #include <sys/types.h>
26 #include <unistd.h>
27 
28 #ifndef ETH_MAX_MTU
29 #define ETH_MAX_MTU	0xFFFFU
30 #endif
31 
32 #ifndef UDP_SEGMENT
33 #define UDP_SEGMENT		103
34 #endif
35 
36 #ifndef UDP_MAX_SEGMENTS
37 #define UDP_MAX_SEGMENTS	(1 << 6UL)
38 #endif
39 
40 #define CONST_MTU_TEST	1500
41 
42 #define CONST_HDRLEN_V4		(sizeof(struct iphdr) + sizeof(struct udphdr))
43 #define CONST_HDRLEN_V6		(sizeof(struct ip6_hdr) + sizeof(struct udphdr))
44 
45 #define CONST_MSS_V4		(CONST_MTU_TEST - CONST_HDRLEN_V4)
46 #define CONST_MSS_V6		(CONST_MTU_TEST - CONST_HDRLEN_V6)
47 
48 #define CONST_MAX_SEGS_V4	(ETH_MAX_MTU / CONST_MSS_V4)
49 #define CONST_MAX_SEGS_V6	(ETH_MAX_MTU / CONST_MSS_V6)
50 
51 static bool		cfg_do_ipv4;
52 static bool		cfg_do_ipv6;
53 static bool		cfg_do_connected;
54 static bool		cfg_do_connectionless;
55 static bool		cfg_do_msgmore;
56 static bool		cfg_do_setsockopt;
57 static int		cfg_specific_test_id = -1;
58 
59 static const char	cfg_ifname[] = "lo";
60 static unsigned short	cfg_port = 9000;
61 
62 static char buf[ETH_MAX_MTU];
63 
64 struct testcase {
65 	int tlen;		/* send() buffer size, may exceed mss */
66 	bool tfail;		/* send() call is expected to fail */
67 	int gso_len;		/* mss after applying gso */
68 	int r_num_mss;		/* recv(): number of calls of full mss */
69 	int r_len_last;		/* recv(): size of last non-mss dgram, if any */
70 };
71 
72 const struct in6_addr addr6 = IN6ADDR_LOOPBACK_INIT;
73 const struct in_addr addr4 = { .s_addr = __constant_htonl(INADDR_LOOPBACK + 2) };
74 
75 struct testcase testcases_v4[] = {
76 	{
77 		/* no GSO: send a single byte */
78 		.tlen = 1,
79 		.r_len_last = 1,
80 	},
81 	{
82 		/* no GSO: send a single MSS */
83 		.tlen = CONST_MSS_V4,
84 		.r_num_mss = 1,
85 	},
86 	{
87 		/* no GSO: send a single MSS + 1B: fail */
88 		.tlen = CONST_MSS_V4 + 1,
89 		.tfail = true,
90 	},
91 	{
92 		/* send a single MSS: will fall back to no GSO */
93 		.tlen = CONST_MSS_V4,
94 		.gso_len = CONST_MSS_V4,
95 		.r_num_mss = 1,
96 	},
97 	{
98 		/* send a single MSS + 1B */
99 		.tlen = CONST_MSS_V4 + 1,
100 		.gso_len = CONST_MSS_V4,
101 		.r_num_mss = 1,
102 		.r_len_last = 1,
103 	},
104 	{
105 		/* send exactly 2 MSS */
106 		.tlen = CONST_MSS_V4 * 2,
107 		.gso_len = CONST_MSS_V4,
108 		.r_num_mss = 2,
109 	},
110 	{
111 		/* send 2 MSS + 1B */
112 		.tlen = (CONST_MSS_V4 * 2) + 1,
113 		.gso_len = CONST_MSS_V4,
114 		.r_num_mss = 2,
115 		.r_len_last = 1,
116 	},
117 	{
118 		/* send MAX segs */
119 		.tlen = (ETH_MAX_MTU / CONST_MSS_V4) * CONST_MSS_V4,
120 		.gso_len = CONST_MSS_V4,
121 		.r_num_mss = (ETH_MAX_MTU / CONST_MSS_V4),
122 	},
123 
124 	{
125 		/* send MAX bytes */
126 		.tlen = ETH_MAX_MTU - CONST_HDRLEN_V4,
127 		.gso_len = CONST_MSS_V4,
128 		.r_num_mss = CONST_MAX_SEGS_V4,
129 		.r_len_last = ETH_MAX_MTU - CONST_HDRLEN_V4 -
130 			      (CONST_MAX_SEGS_V4 * CONST_MSS_V4),
131 	},
132 	{
133 		/* send MAX + 1: fail */
134 		.tlen = ETH_MAX_MTU - CONST_HDRLEN_V4 + 1,
135 		.gso_len = CONST_MSS_V4,
136 		.tfail = true,
137 	},
138 	{
139 		/* send a single 1B MSS: will fall back to no GSO */
140 		.tlen = 1,
141 		.gso_len = 1,
142 		.r_num_mss = 1,
143 	},
144 	{
145 		/* send 2 1B segments */
146 		.tlen = 2,
147 		.gso_len = 1,
148 		.r_num_mss = 2,
149 	},
150 	{
151 		/* send 2B + 2B + 1B segments */
152 		.tlen = 5,
153 		.gso_len = 2,
154 		.r_num_mss = 2,
155 		.r_len_last = 1,
156 	},
157 	{
158 		/* send max number of min sized segments */
159 		.tlen = UDP_MAX_SEGMENTS,
160 		.gso_len = 1,
161 		.r_num_mss = UDP_MAX_SEGMENTS,
162 	},
163 	{
164 		/* send max number + 1 of min sized segments: fail */
165 		.tlen = UDP_MAX_SEGMENTS + 1,
166 		.gso_len = 1,
167 		.tfail = true,
168 	},
169 	{
170 		/* EOL */
171 	}
172 };
173 
174 #ifndef IP6_MAX_MTU
175 #define IP6_MAX_MTU	(ETH_MAX_MTU + sizeof(struct ip6_hdr))
176 #endif
177 
178 struct testcase testcases_v6[] = {
179 	{
180 		/* no GSO: send a single byte */
181 		.tlen = 1,
182 		.r_len_last = 1,
183 	},
184 	{
185 		/* no GSO: send a single MSS */
186 		.tlen = CONST_MSS_V6,
187 		.r_num_mss = 1,
188 	},
189 	{
190 		/* no GSO: send a single MSS + 1B: fail */
191 		.tlen = CONST_MSS_V6 + 1,
192 		.tfail = true,
193 	},
194 	{
195 		/* send a single MSS: will fall back to no GSO */
196 		.tlen = CONST_MSS_V6,
197 		.gso_len = CONST_MSS_V6,
198 		.r_num_mss = 1,
199 	},
200 	{
201 		/* send a single MSS + 1B */
202 		.tlen = CONST_MSS_V6 + 1,
203 		.gso_len = CONST_MSS_V6,
204 		.r_num_mss = 1,
205 		.r_len_last = 1,
206 	},
207 	{
208 		/* send exactly 2 MSS */
209 		.tlen = CONST_MSS_V6 * 2,
210 		.gso_len = CONST_MSS_V6,
211 		.r_num_mss = 2,
212 	},
213 	{
214 		/* send 2 MSS + 1B */
215 		.tlen = (CONST_MSS_V6 * 2) + 1,
216 		.gso_len = CONST_MSS_V6,
217 		.r_num_mss = 2,
218 		.r_len_last = 1,
219 	},
220 	{
221 		/* send MAX segs */
222 		.tlen = (IP6_MAX_MTU / CONST_MSS_V6) * CONST_MSS_V6,
223 		.gso_len = CONST_MSS_V6,
224 		.r_num_mss = (IP6_MAX_MTU / CONST_MSS_V6),
225 	},
226 
227 	{
228 		/* send MAX bytes */
229 		.tlen = IP6_MAX_MTU - CONST_HDRLEN_V6,
230 		.gso_len = CONST_MSS_V6,
231 		.r_num_mss = CONST_MAX_SEGS_V6,
232 		.r_len_last = IP6_MAX_MTU - CONST_HDRLEN_V6 -
233 			      (CONST_MAX_SEGS_V6 * CONST_MSS_V6),
234 	},
235 	{
236 		/* send MAX + 1: fail */
237 		.tlen = IP6_MAX_MTU - CONST_HDRLEN_V6 + 1,
238 		.gso_len = CONST_MSS_V6,
239 		.tfail = true,
240 	},
241 	{
242 		/* send a single 1B MSS: will fall back to no GSO */
243 		.tlen = 1,
244 		.gso_len = 1,
245 		.r_num_mss = 1,
246 	},
247 	{
248 		/* send 2 1B segments */
249 		.tlen = 2,
250 		.gso_len = 1,
251 		.r_num_mss = 2,
252 	},
253 	{
254 		/* send 2B + 2B + 1B segments */
255 		.tlen = 5,
256 		.gso_len = 2,
257 		.r_num_mss = 2,
258 		.r_len_last = 1,
259 	},
260 	{
261 		/* send max number of min sized segments */
262 		.tlen = UDP_MAX_SEGMENTS,
263 		.gso_len = 1,
264 		.r_num_mss = UDP_MAX_SEGMENTS,
265 	},
266 	{
267 		/* send max number + 1 of min sized segments: fail */
268 		.tlen = UDP_MAX_SEGMENTS + 1,
269 		.gso_len = 1,
270 		.tfail = true,
271 	},
272 	{
273 		/* EOL */
274 	}
275 };
276 
277 static unsigned int get_device_mtu(int fd, const char *ifname)
278 {
279 	struct ifreq ifr;
280 
281 	memset(&ifr, 0, sizeof(ifr));
282 
283 	strcpy(ifr.ifr_name, ifname);
284 
285 	if (ioctl(fd, SIOCGIFMTU, &ifr))
286 		error(1, errno, "ioctl get mtu");
287 
288 	return ifr.ifr_mtu;
289 }
290 
291 static void __set_device_mtu(int fd, const char *ifname, unsigned int mtu)
292 {
293 	struct ifreq ifr;
294 
295 	memset(&ifr, 0, sizeof(ifr));
296 
297 	ifr.ifr_mtu = mtu;
298 	strcpy(ifr.ifr_name, ifname);
299 
300 	if (ioctl(fd, SIOCSIFMTU, &ifr))
301 		error(1, errno, "ioctl set mtu");
302 }
303 
304 static void set_device_mtu(int fd, int mtu)
305 {
306 	int val;
307 
308 	val = get_device_mtu(fd, cfg_ifname);
309 	fprintf(stderr, "device mtu (orig): %u\n", val);
310 
311 	__set_device_mtu(fd, cfg_ifname, mtu);
312 	val = get_device_mtu(fd, cfg_ifname);
313 	if (val != mtu)
314 		error(1, 0, "unable to set device mtu to %u\n", val);
315 
316 	fprintf(stderr, "device mtu (test): %u\n", val);
317 }
318 
319 static void set_pmtu_discover(int fd, bool is_ipv4)
320 {
321 	int level, name, val;
322 
323 	if (is_ipv4) {
324 		level	= SOL_IP;
325 		name	= IP_MTU_DISCOVER;
326 		val	= IP_PMTUDISC_DO;
327 	} else {
328 		level	= SOL_IPV6;
329 		name	= IPV6_MTU_DISCOVER;
330 		val	= IPV6_PMTUDISC_DO;
331 	}
332 
333 	if (setsockopt(fd, level, name, &val, sizeof(val)))
334 		error(1, errno, "setsockopt path mtu");
335 }
336 
337 static unsigned int get_path_mtu(int fd, bool is_ipv4)
338 {
339 	socklen_t vallen;
340 	unsigned int mtu;
341 	int ret;
342 
343 	vallen = sizeof(mtu);
344 	if (is_ipv4)
345 		ret = getsockopt(fd, SOL_IP, IP_MTU, &mtu, &vallen);
346 	else
347 		ret = getsockopt(fd, SOL_IPV6, IPV6_MTU, &mtu, &vallen);
348 
349 	if (ret)
350 		error(1, errno, "getsockopt mtu");
351 
352 
353 	fprintf(stderr, "path mtu (read):  %u\n", mtu);
354 	return mtu;
355 }
356 
357 /* very wordy version of system("ip route add dev lo mtu 1500 127.0.0.3/32") */
358 static void set_route_mtu(int mtu, bool is_ipv4)
359 {
360 	struct sockaddr_nl nladdr = { .nl_family = AF_NETLINK };
361 	struct nlmsghdr *nh;
362 	struct rtattr *rta;
363 	struct rtmsg *rt;
364 	char data[NLMSG_ALIGN(sizeof(*nh)) +
365 		  NLMSG_ALIGN(sizeof(*rt)) +
366 		  NLMSG_ALIGN(RTA_LENGTH(sizeof(addr6))) +
367 		  NLMSG_ALIGN(RTA_LENGTH(sizeof(int))) +
368 		  NLMSG_ALIGN(RTA_LENGTH(0) + RTA_LENGTH(sizeof(int)))];
369 	int fd, ret, alen, off = 0;
370 
371 	alen = is_ipv4 ? sizeof(addr4) : sizeof(addr6);
372 
373 	fd = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE);
374 	if (fd == -1)
375 		error(1, errno, "socket netlink");
376 
377 	memset(data, 0, sizeof(data));
378 
379 	nh = (void *)data;
380 	nh->nlmsg_type = RTM_NEWROUTE;
381 	nh->nlmsg_flags = NLM_F_REQUEST | NLM_F_CREATE;
382 	off += NLMSG_ALIGN(sizeof(*nh));
383 
384 	rt = (void *)(data + off);
385 	rt->rtm_family = is_ipv4 ? AF_INET : AF_INET6;
386 	rt->rtm_table = RT_TABLE_MAIN;
387 	rt->rtm_dst_len = alen << 3;
388 	rt->rtm_protocol = RTPROT_BOOT;
389 	rt->rtm_scope = RT_SCOPE_UNIVERSE;
390 	rt->rtm_type = RTN_UNICAST;
391 	off += NLMSG_ALIGN(sizeof(*rt));
392 
393 	rta = (void *)(data + off);
394 	rta->rta_type = RTA_DST;
395 	rta->rta_len = RTA_LENGTH(alen);
396 	if (is_ipv4)
397 		memcpy(RTA_DATA(rta), &addr4, alen);
398 	else
399 		memcpy(RTA_DATA(rta), &addr6, alen);
400 	off += NLMSG_ALIGN(rta->rta_len);
401 
402 	rta = (void *)(data + off);
403 	rta->rta_type = RTA_OIF;
404 	rta->rta_len = RTA_LENGTH(sizeof(int));
405 	*((int *)(RTA_DATA(rta))) = 1; //if_nametoindex("lo");
406 	off += NLMSG_ALIGN(rta->rta_len);
407 
408 	/* MTU is a subtype in a metrics type */
409 	rta = (void *)(data + off);
410 	rta->rta_type = RTA_METRICS;
411 	rta->rta_len = RTA_LENGTH(0) + RTA_LENGTH(sizeof(int));
412 	off += NLMSG_ALIGN(rta->rta_len);
413 
414 	/* now fill MTU subtype. Note that it fits within above rta_len */
415 	rta = (void *)(((char *) rta) + RTA_LENGTH(0));
416 	rta->rta_type = RTAX_MTU;
417 	rta->rta_len = RTA_LENGTH(sizeof(int));
418 	*((int *)(RTA_DATA(rta))) = mtu;
419 
420 	nh->nlmsg_len = off;
421 
422 	ret = sendto(fd, data, off, 0, (void *)&nladdr, sizeof(nladdr));
423 	if (ret != off)
424 		error(1, errno, "send netlink: %uB != %uB\n", ret, off);
425 
426 	if (close(fd))
427 		error(1, errno, "close netlink");
428 
429 	fprintf(stderr, "route mtu (test): %u\n", mtu);
430 }
431 
432 static bool __send_one(int fd, struct msghdr *msg, int flags)
433 {
434 	int ret;
435 
436 	ret = sendmsg(fd, msg, flags);
437 	if (ret == -1 &&
438 	    (errno == EMSGSIZE || errno == ENOMEM || errno == EINVAL))
439 		return false;
440 	if (ret == -1)
441 		error(1, errno, "sendmsg");
442 	if (ret != msg->msg_iov->iov_len)
443 		error(1, 0, "sendto: %d != %llu", ret,
444 			(unsigned long long)msg->msg_iov->iov_len);
445 	if (msg->msg_flags)
446 		error(1, 0, "sendmsg: return flags 0x%x\n", msg->msg_flags);
447 
448 	return true;
449 }
450 
451 static bool send_one(int fd, int len, int gso_len,
452 		     struct sockaddr *addr, socklen_t alen)
453 {
454 	char control[CMSG_SPACE(sizeof(uint16_t))] = {0};
455 	struct msghdr msg = {0};
456 	struct iovec iov = {0};
457 	struct cmsghdr *cm;
458 
459 	iov.iov_base = buf;
460 	iov.iov_len = len;
461 
462 	msg.msg_iov = &iov;
463 	msg.msg_iovlen = 1;
464 
465 	msg.msg_name = addr;
466 	msg.msg_namelen = alen;
467 
468 	if (gso_len && !cfg_do_setsockopt) {
469 		msg.msg_control = control;
470 		msg.msg_controllen = sizeof(control);
471 
472 		cm = CMSG_FIRSTHDR(&msg);
473 		cm->cmsg_level = SOL_UDP;
474 		cm->cmsg_type = UDP_SEGMENT;
475 		cm->cmsg_len = CMSG_LEN(sizeof(uint16_t));
476 		*((uint16_t *) CMSG_DATA(cm)) = gso_len;
477 	}
478 
479 	/* If MSG_MORE, send 1 byte followed by remainder */
480 	if (cfg_do_msgmore && len > 1) {
481 		iov.iov_len = 1;
482 		if (!__send_one(fd, &msg, MSG_MORE))
483 			error(1, 0, "send 1B failed");
484 
485 		iov.iov_base++;
486 		iov.iov_len = len - 1;
487 	}
488 
489 	return __send_one(fd, &msg, 0);
490 }
491 
492 static int recv_one(int fd, int flags)
493 {
494 	int ret;
495 
496 	ret = recv(fd, buf, sizeof(buf), flags);
497 	if (ret == -1 && errno == EAGAIN && (flags & MSG_DONTWAIT))
498 		return 0;
499 	if (ret == -1)
500 		error(1, errno, "recv");
501 
502 	return ret;
503 }
504 
505 static void run_one(struct testcase *test, int fdt, int fdr,
506 		    struct sockaddr *addr, socklen_t alen)
507 {
508 	int i, ret, val, mss;
509 	bool sent;
510 
511 	fprintf(stderr, "ipv%d tx:%d gso:%d %s\n",
512 			addr->sa_family == AF_INET ? 4 : 6,
513 			test->tlen, test->gso_len,
514 			test->tfail ? "(fail)" : "");
515 
516 	val = test->gso_len;
517 	if (cfg_do_setsockopt) {
518 		if (setsockopt(fdt, SOL_UDP, UDP_SEGMENT, &val, sizeof(val)))
519 			error(1, errno, "setsockopt udp segment");
520 	}
521 
522 	sent = send_one(fdt, test->tlen, test->gso_len, addr, alen);
523 	if (sent && test->tfail)
524 		error(1, 0, "send succeeded while expecting failure");
525 	if (!sent && !test->tfail)
526 		error(1, 0, "send failed while expecting success");
527 	if (!sent)
528 		return;
529 
530 	if (test->gso_len)
531 		mss = test->gso_len;
532 	else
533 		mss = addr->sa_family == AF_INET ? CONST_MSS_V4 : CONST_MSS_V6;
534 
535 
536 	/* Recv all full MSS datagrams */
537 	for (i = 0; i < test->r_num_mss; i++) {
538 		ret = recv_one(fdr, 0);
539 		if (ret != mss)
540 			error(1, 0, "recv.%d: %d != %d", i, ret, mss);
541 	}
542 
543 	/* Recv the non-full last datagram, if tlen was not a multiple of mss */
544 	if (test->r_len_last) {
545 		ret = recv_one(fdr, 0);
546 		if (ret != test->r_len_last)
547 			error(1, 0, "recv.%d: %d != %d (last)",
548 			      i, ret, test->r_len_last);
549 	}
550 
551 	/* Verify received all data */
552 	ret = recv_one(fdr, MSG_DONTWAIT);
553 	if (ret)
554 		error(1, 0, "recv: unexpected datagram");
555 }
556 
557 static void run_all(int fdt, int fdr, struct sockaddr *addr, socklen_t alen)
558 {
559 	struct testcase *tests, *test;
560 
561 	tests = addr->sa_family == AF_INET ? testcases_v4 : testcases_v6;
562 
563 	for (test = tests; test->tlen; test++) {
564 		/* if a specific test is given, then skip all others */
565 		if (cfg_specific_test_id == -1 ||
566 		    cfg_specific_test_id == test - tests)
567 			run_one(test, fdt, fdr, addr, alen);
568 	}
569 }
570 
571 static void run_test(struct sockaddr *addr, socklen_t alen)
572 {
573 	struct timeval tv = { .tv_usec = 100 * 1000 };
574 	int fdr, fdt, val;
575 
576 	fdr = socket(addr->sa_family, SOCK_DGRAM, 0);
577 	if (fdr == -1)
578 		error(1, errno, "socket r");
579 
580 	if (bind(fdr, addr, alen))
581 		error(1, errno, "bind");
582 
583 	/* Have tests fail quickly instead of hang */
584 	if (setsockopt(fdr, SOL_SOCKET, SO_RCVTIMEO, &tv, sizeof(tv)))
585 		error(1, errno, "setsockopt rcv timeout");
586 
587 	fdt = socket(addr->sa_family, SOCK_DGRAM, 0);
588 	if (fdt == -1)
589 		error(1, errno, "socket t");
590 
591 	/* Do not fragment these datagrams: only succeed if GSO works */
592 	set_pmtu_discover(fdt, addr->sa_family == AF_INET);
593 
594 	if (cfg_do_connectionless) {
595 		set_device_mtu(fdt, CONST_MTU_TEST);
596 		run_all(fdt, fdr, addr, alen);
597 	}
598 
599 	if (cfg_do_connected) {
600 		set_device_mtu(fdt, CONST_MTU_TEST + 100);
601 		set_route_mtu(CONST_MTU_TEST, addr->sa_family == AF_INET);
602 
603 		if (connect(fdt, addr, alen))
604 			error(1, errno, "connect");
605 
606 		val = get_path_mtu(fdt, addr->sa_family == AF_INET);
607 		if (val != CONST_MTU_TEST)
608 			error(1, 0, "bad path mtu %u\n", val);
609 
610 		run_all(fdt, fdr, addr, 0 /* use connected addr */);
611 	}
612 
613 	if (close(fdt))
614 		error(1, errno, "close t");
615 	if (close(fdr))
616 		error(1, errno, "close r");
617 }
618 
619 static void run_test_v4(void)
620 {
621 	struct sockaddr_in addr = {0};
622 
623 	addr.sin_family = AF_INET;
624 	addr.sin_port = htons(cfg_port);
625 	addr.sin_addr = addr4;
626 
627 	run_test((void *)&addr, sizeof(addr));
628 }
629 
630 static void run_test_v6(void)
631 {
632 	struct sockaddr_in6 addr = {0};
633 
634 	addr.sin6_family = AF_INET6;
635 	addr.sin6_port = htons(cfg_port);
636 	addr.sin6_addr = addr6;
637 
638 	run_test((void *)&addr, sizeof(addr));
639 }
640 
641 static void parse_opts(int argc, char **argv)
642 {
643 	int c;
644 
645 	while ((c = getopt(argc, argv, "46cCmst:")) != -1) {
646 		switch (c) {
647 		case '4':
648 			cfg_do_ipv4 = true;
649 			break;
650 		case '6':
651 			cfg_do_ipv6 = true;
652 			break;
653 		case 'c':
654 			cfg_do_connected = true;
655 			break;
656 		case 'C':
657 			cfg_do_connectionless = true;
658 			break;
659 		case 'm':
660 			cfg_do_msgmore = true;
661 			break;
662 		case 's':
663 			cfg_do_setsockopt = true;
664 			break;
665 		case 't':
666 			cfg_specific_test_id = strtoul(optarg, NULL, 0);
667 			break;
668 		default:
669 			error(1, 0, "%s: parse error", argv[0]);
670 		}
671 	}
672 }
673 
674 int main(int argc, char **argv)
675 {
676 	parse_opts(argc, argv);
677 
678 	if (cfg_do_ipv4)
679 		run_test_v4();
680 	if (cfg_do_ipv6)
681 		run_test_v6();
682 
683 	fprintf(stderr, "OK\n");
684 	return 0;
685 }
686