xref: /linux/tools/testing/selftests/net/nettest.c (revision 75b1a8f9d62e50f05d0e4e9f3c8bcde32527ffc1)
1 // SPDX-License-Identifier: GPL-2.0
2 /* nettest - used for functional tests of networking APIs
3  *
4  * Copyright (c) 2013-2019 David Ahern <dsahern@gmail.com>. All rights reserved.
5  */
6 
7 #define _GNU_SOURCE
8 #include <features.h>
9 #include <sys/types.h>
10 #include <sys/ioctl.h>
11 #include <sys/socket.h>
12 #include <linux/tcp.h>
13 #include <arpa/inet.h>
14 #include <net/if.h>
15 #include <netinet/in.h>
16 #include <netdb.h>
17 #include <fcntl.h>
18 #include <libgen.h>
19 #include <limits.h>
20 #include <stdarg.h>
21 #include <stdio.h>
22 #include <stdlib.h>
23 #include <string.h>
24 #include <unistd.h>
25 #include <time.h>
26 #include <errno.h>
27 
28 #ifndef IPV6_UNICAST_IF
29 #define IPV6_UNICAST_IF         76
30 #endif
31 #ifndef IPV6_MULTICAST_IF
32 #define IPV6_MULTICAST_IF       17
33 #endif
34 
35 #define DEFAULT_PORT 12345
36 
37 #ifndef MAX
38 #define MAX(a, b)  ((a) > (b) ? (a) : (b))
39 #endif
40 #ifndef MIN
41 #define MIN(a, b)  ((a) < (b) ? (a) : (b))
42 #endif
43 
44 struct sock_args {
45 	/* local address */
46 	union {
47 		struct in_addr  in;
48 		struct in6_addr in6;
49 	} local_addr;
50 
51 	/* remote address */
52 	union {
53 		struct in_addr  in;
54 		struct in6_addr in6;
55 	} remote_addr;
56 	int scope_id;  /* remote scope; v6 send only */
57 
58 	struct in_addr grp;     /* multicast group */
59 
60 	unsigned int has_local_ip:1,
61 		     has_remote_ip:1,
62 		     has_grp:1,
63 		     has_expected_laddr:1,
64 		     has_expected_raddr:1,
65 		     bind_test_only:1;
66 
67 	unsigned short port;
68 
69 	int type;      /* DGRAM, STREAM, RAW */
70 	int protocol;
71 	int version;   /* AF_INET/AF_INET6 */
72 
73 	int use_setsockopt;
74 	int use_cmsg;
75 	const char *dev;
76 	int ifindex;
77 
78 	const char *password;
79 	/* prefix for MD5 password */
80 	union {
81 		struct sockaddr_in v4;
82 		struct sockaddr_in6 v6;
83 	} md5_prefix;
84 	unsigned int prefix_len;
85 
86 	/* expected addresses and device index for connection */
87 	int expected_ifindex;
88 
89 	/* local address */
90 	union {
91 		struct in_addr  in;
92 		struct in6_addr in6;
93 	} expected_laddr;
94 
95 	/* remote address */
96 	union {
97 		struct in_addr  in;
98 		struct in6_addr in6;
99 	} expected_raddr;
100 };
101 
102 static int server_mode;
103 static unsigned int prog_timeout = 5;
104 static unsigned int interactive;
105 static int iter = 1;
106 static char *msg = "Hello world!";
107 static int msglen;
108 static int quiet;
109 static int try_broadcast = 1;
110 
111 static char *timestamp(char *timebuf, int buflen)
112 {
113 	time_t now;
114 
115 	now = time(NULL);
116 	if (strftime(timebuf, buflen, "%T", localtime(&now)) == 0) {
117 		memset(timebuf, 0, buflen);
118 		strncpy(timebuf, "00:00:00", buflen-1);
119 	}
120 
121 	return timebuf;
122 }
123 
124 static void log_msg(const char *format, ...)
125 {
126 	char timebuf[64];
127 	va_list args;
128 
129 	if (quiet)
130 		return;
131 
132 	fprintf(stdout, "%s %s:",
133 		timestamp(timebuf, sizeof(timebuf)),
134 		server_mode ? "server" : "client");
135 	va_start(args, format);
136 	vfprintf(stdout, format, args);
137 	va_end(args);
138 
139 	fflush(stdout);
140 }
141 
142 static void log_error(const char *format, ...)
143 {
144 	char timebuf[64];
145 	va_list args;
146 
147 	if (quiet)
148 		return;
149 
150 	fprintf(stderr, "%s %s:",
151 		timestamp(timebuf, sizeof(timebuf)),
152 		server_mode ? "server" : "client");
153 	va_start(args, format);
154 	vfprintf(stderr, format, args);
155 	va_end(args);
156 
157 	fflush(stderr);
158 }
159 
160 static void log_err_errno(const char *fmt, ...)
161 {
162 	char timebuf[64];
163 	va_list args;
164 
165 	if (quiet)
166 		return;
167 
168 	fprintf(stderr, "%s %s: ",
169 		timestamp(timebuf, sizeof(timebuf)),
170 		server_mode ? "server" : "client");
171 	va_start(args, fmt);
172 	vfprintf(stderr, fmt, args);
173 	va_end(args);
174 
175 	fprintf(stderr, ": %d: %s\n", errno, strerror(errno));
176 	fflush(stderr);
177 }
178 
179 static void log_address(const char *desc, struct sockaddr *sa)
180 {
181 	char addrstr[64];
182 
183 	if (quiet)
184 		return;
185 
186 	if (sa->sa_family == AF_INET) {
187 		struct sockaddr_in *s = (struct sockaddr_in *) sa;
188 
189 		log_msg("%s %s:%d",
190 			desc,
191 			inet_ntop(AF_INET, &s->sin_addr, addrstr,
192 				  sizeof(addrstr)),
193 			ntohs(s->sin_port));
194 
195 	} else if (sa->sa_family == AF_INET6) {
196 		struct sockaddr_in6 *s6 = (struct sockaddr_in6 *) sa;
197 
198 		log_msg("%s [%s]:%d",
199 			desc,
200 			inet_ntop(AF_INET6, &s6->sin6_addr, addrstr,
201 				  sizeof(addrstr)),
202 			ntohs(s6->sin6_port));
203 	}
204 
205 	printf("\n");
206 
207 	fflush(stdout);
208 }
209 
210 static int tcp_md5sig(int sd, void *addr, socklen_t alen, struct sock_args *args)
211 {
212 	int keylen = strlen(args->password);
213 	struct tcp_md5sig md5sig = {};
214 	int opt = TCP_MD5SIG;
215 	int rc;
216 
217 	md5sig.tcpm_keylen = keylen;
218 	memcpy(md5sig.tcpm_key, args->password, keylen);
219 
220 	if (args->prefix_len) {
221 		opt = TCP_MD5SIG_EXT;
222 		md5sig.tcpm_flags |= TCP_MD5SIG_FLAG_PREFIX;
223 
224 		md5sig.tcpm_prefixlen = args->prefix_len;
225 		addr = &args->md5_prefix;
226 	}
227 	memcpy(&md5sig.tcpm_addr, addr, alen);
228 
229 	if (args->ifindex) {
230 		opt = TCP_MD5SIG_EXT;
231 		md5sig.tcpm_flags |= TCP_MD5SIG_FLAG_IFINDEX;
232 
233 		md5sig.tcpm_ifindex = args->ifindex;
234 	}
235 
236 	rc = setsockopt(sd, IPPROTO_TCP, opt, &md5sig, sizeof(md5sig));
237 	if (rc < 0) {
238 		/* ENOENT is harmless. Returned when a password is cleared */
239 		if (errno == ENOENT)
240 			rc = 0;
241 		else
242 			log_err_errno("setsockopt(TCP_MD5SIG)");
243 	}
244 
245 	return rc;
246 }
247 
248 static int tcp_md5_remote(int sd, struct sock_args *args)
249 {
250 	struct sockaddr_in sin = {
251 		.sin_family = AF_INET,
252 	};
253 	struct sockaddr_in6 sin6 = {
254 		.sin6_family = AF_INET6,
255 	};
256 	void *addr;
257 	int alen;
258 
259 	switch (args->version) {
260 	case AF_INET:
261 		sin.sin_port = htons(args->port);
262 		sin.sin_addr = args->remote_addr.in;
263 		addr = &sin;
264 		alen = sizeof(sin);
265 		break;
266 	case AF_INET6:
267 		sin6.sin6_port = htons(args->port);
268 		sin6.sin6_addr = args->remote_addr.in6;
269 		addr = &sin6;
270 		alen = sizeof(sin6);
271 		break;
272 	default:
273 		log_error("unknown address family\n");
274 		exit(1);
275 	}
276 
277 	if (tcp_md5sig(sd, addr, alen, args))
278 		return -1;
279 
280 	return 0;
281 }
282 
283 static int get_ifidx(const char *ifname)
284 {
285 	struct ifreq ifdata;
286 	int sd, rc;
287 
288 	if (!ifname || *ifname == '\0')
289 		return -1;
290 
291 	memset(&ifdata, 0, sizeof(ifdata));
292 
293 	strcpy(ifdata.ifr_name, ifname);
294 
295 	sd = socket(PF_INET, SOCK_DGRAM, IPPROTO_IP);
296 	if (sd < 0) {
297 		log_err_errno("socket failed");
298 		return -1;
299 	}
300 
301 	rc = ioctl(sd, SIOCGIFINDEX, (char *)&ifdata);
302 	close(sd);
303 	if (rc != 0) {
304 		log_err_errno("ioctl(SIOCGIFINDEX) failed");
305 		return -1;
306 	}
307 
308 	return ifdata.ifr_ifindex;
309 }
310 
311 static int bind_to_device(int sd, const char *name)
312 {
313 	int rc;
314 
315 	rc = setsockopt(sd, SOL_SOCKET, SO_BINDTODEVICE, name, strlen(name)+1);
316 	if (rc < 0)
317 		log_err_errno("setsockopt(SO_BINDTODEVICE)");
318 
319 	return rc;
320 }
321 
322 static int get_bind_to_device(int sd, char *name, size_t len)
323 {
324 	int rc;
325 	socklen_t optlen = len;
326 
327 	name[0] = '\0';
328 	rc = getsockopt(sd, SOL_SOCKET, SO_BINDTODEVICE, name, &optlen);
329 	if (rc < 0)
330 		log_err_errno("setsockopt(SO_BINDTODEVICE)");
331 
332 	return rc;
333 }
334 
335 static int check_device(int sd, struct sock_args *args)
336 {
337 	int ifindex = 0;
338 	char name[32];
339 
340 	if (get_bind_to_device(sd, name, sizeof(name)))
341 		*name = '\0';
342 	else
343 		ifindex = get_ifidx(name);
344 
345 	log_msg("    bound to device %s/%d\n",
346 		*name ? name : "<none>", ifindex);
347 
348 	if (!args->expected_ifindex)
349 		return 0;
350 
351 	if (args->expected_ifindex != ifindex) {
352 		log_error("Device index mismatch: expected %d have %d\n",
353 			  args->expected_ifindex, ifindex);
354 		return 1;
355 	}
356 
357 	log_msg("Device index matches: expected %d have %d\n",
358 		args->expected_ifindex, ifindex);
359 
360 	return 0;
361 }
362 
363 static int set_pktinfo_v4(int sd)
364 {
365 	int one = 1;
366 	int rc;
367 
368 	rc = setsockopt(sd, SOL_IP, IP_PKTINFO, &one, sizeof(one));
369 	if (rc < 0 && rc != -ENOTSUP)
370 		log_err_errno("setsockopt(IP_PKTINFO)");
371 
372 	return rc;
373 }
374 
375 static int set_recvpktinfo_v6(int sd)
376 {
377 	int one = 1;
378 	int rc;
379 
380 	rc = setsockopt(sd, SOL_IPV6, IPV6_RECVPKTINFO, &one, sizeof(one));
381 	if (rc < 0 && rc != -ENOTSUP)
382 		log_err_errno("setsockopt(IPV6_RECVPKTINFO)");
383 
384 	return rc;
385 }
386 
387 static int set_recverr_v4(int sd)
388 {
389 	int one = 1;
390 	int rc;
391 
392 	rc = setsockopt(sd, SOL_IP, IP_RECVERR, &one, sizeof(one));
393 	if (rc < 0 && rc != -ENOTSUP)
394 		log_err_errno("setsockopt(IP_RECVERR)");
395 
396 	return rc;
397 }
398 
399 static int set_recverr_v6(int sd)
400 {
401 	int one = 1;
402 	int rc;
403 
404 	rc = setsockopt(sd, SOL_IPV6, IPV6_RECVERR, &one, sizeof(one));
405 	if (rc < 0 && rc != -ENOTSUP)
406 		log_err_errno("setsockopt(IPV6_RECVERR)");
407 
408 	return rc;
409 }
410 
411 static int set_unicast_if(int sd, int ifindex, int version)
412 {
413 	int opt = IP_UNICAST_IF;
414 	int level = SOL_IP;
415 	int rc;
416 
417 	ifindex = htonl(ifindex);
418 
419 	if (version == AF_INET6) {
420 		opt = IPV6_UNICAST_IF;
421 		level = SOL_IPV6;
422 	}
423 	rc = setsockopt(sd, level, opt, &ifindex, sizeof(ifindex));
424 	if (rc < 0)
425 		log_err_errno("setsockopt(IP_UNICAST_IF)");
426 
427 	return rc;
428 }
429 
430 static int set_multicast_if(int sd, int ifindex)
431 {
432 	struct ip_mreqn mreq = { .imr_ifindex = ifindex };
433 	int rc;
434 
435 	rc = setsockopt(sd, SOL_IP, IP_MULTICAST_IF, &mreq, sizeof(mreq));
436 	if (rc < 0)
437 		log_err_errno("setsockopt(IP_MULTICAST_IF)");
438 
439 	return rc;
440 }
441 
442 static int set_membership(int sd, uint32_t grp, uint32_t addr, int ifindex)
443 {
444 	uint32_t if_addr = addr;
445 	struct ip_mreqn mreq;
446 	int rc;
447 
448 	if (addr == htonl(INADDR_ANY) && !ifindex) {
449 		log_error("Either local address or device needs to be given for multicast membership\n");
450 		return -1;
451 	}
452 
453 	mreq.imr_multiaddr.s_addr = grp;
454 	mreq.imr_address.s_addr = if_addr;
455 	mreq.imr_ifindex = ifindex;
456 
457 	rc = setsockopt(sd, IPPROTO_IP, IP_ADD_MEMBERSHIP, &mreq, sizeof(mreq));
458 	if (rc < 0) {
459 		log_err_errno("setsockopt(IP_ADD_MEMBERSHIP)");
460 		return -1;
461 	}
462 
463 	return 0;
464 }
465 
466 static int set_broadcast(int sd)
467 {
468 	unsigned int one = 1;
469 	int rc = 0;
470 
471 	if (setsockopt(sd, SOL_SOCKET, SO_BROADCAST, &one, sizeof(one)) != 0) {
472 		log_err_errno("setsockopt(SO_BROADCAST)");
473 		rc = -1;
474 	}
475 
476 	return rc;
477 }
478 
479 static int set_reuseport(int sd)
480 {
481 	unsigned int one = 1;
482 	int rc = 0;
483 
484 	if (setsockopt(sd, SOL_SOCKET, SO_REUSEPORT, &one, sizeof(one)) != 0) {
485 		log_err_errno("setsockopt(SO_REUSEPORT)");
486 		rc = -1;
487 	}
488 
489 	return rc;
490 }
491 
492 static int set_reuseaddr(int sd)
493 {
494 	unsigned int one = 1;
495 	int rc = 0;
496 
497 	if (setsockopt(sd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one)) != 0) {
498 		log_err_errno("setsockopt(SO_REUSEADDR)");
499 		rc = -1;
500 	}
501 
502 	return rc;
503 }
504 
505 static int str_to_uint(const char *str, int min, int max, unsigned int *value)
506 {
507 	int number;
508 	char *end;
509 
510 	errno = 0;
511 	number = (unsigned int) strtoul(str, &end, 0);
512 
513 	/* entire string should be consumed by conversion
514 	 * and value should be between min and max
515 	 */
516 	if (((*end == '\0') || (*end == '\n')) && (end != str) &&
517 	    (errno != ERANGE) && (min <= number) && (number <= max)) {
518 		*value = number;
519 		return 0;
520 	}
521 
522 	return -1;
523 }
524 
525 static int expected_addr_match(struct sockaddr *sa, void *expected,
526 			       const char *desc)
527 {
528 	char addrstr[64];
529 	int rc = 0;
530 
531 	if (sa->sa_family == AF_INET) {
532 		struct sockaddr_in *s = (struct sockaddr_in *) sa;
533 		struct in_addr *exp_in = (struct in_addr *) expected;
534 
535 		if (s->sin_addr.s_addr != exp_in->s_addr) {
536 			log_error("%s address does not match expected %s",
537 				  desc,
538 				  inet_ntop(AF_INET, exp_in,
539 					    addrstr, sizeof(addrstr)));
540 			rc = 1;
541 		}
542 	} else if (sa->sa_family == AF_INET6) {
543 		struct sockaddr_in6 *s6 = (struct sockaddr_in6 *) sa;
544 		struct in6_addr *exp_in = (struct in6_addr *) expected;
545 
546 		if (memcmp(&s6->sin6_addr, exp_in, sizeof(*exp_in))) {
547 			log_error("%s address does not match expected %s",
548 				  desc,
549 				  inet_ntop(AF_INET6, exp_in,
550 					    addrstr, sizeof(addrstr)));
551 			rc = 1;
552 		}
553 	} else {
554 		log_error("%s address does not match expected - unknown family",
555 			  desc);
556 		rc = 1;
557 	}
558 
559 	if (!rc)
560 		log_msg("%s address matches expected\n", desc);
561 
562 	return rc;
563 }
564 
565 static int show_sockstat(int sd, struct sock_args *args)
566 {
567 	struct sockaddr_in6 local_addr, remote_addr;
568 	socklen_t alen = sizeof(local_addr);
569 	struct sockaddr *sa;
570 	const char *desc;
571 	int rc = 0;
572 
573 	desc = server_mode ? "server local:" : "client local:";
574 	sa = (struct sockaddr *) &local_addr;
575 	if (getsockname(sd, sa, &alen) == 0) {
576 		log_address(desc, sa);
577 
578 		if (args->has_expected_laddr) {
579 			rc = expected_addr_match(sa, &args->expected_laddr,
580 						 "local");
581 		}
582 	} else {
583 		log_err_errno("getsockname failed");
584 	}
585 
586 	sa = (struct sockaddr *) &remote_addr;
587 	desc = server_mode ? "server peer:" : "client peer:";
588 	if (getpeername(sd, sa, &alen) == 0) {
589 		log_address(desc, sa);
590 
591 		if (args->has_expected_raddr) {
592 			rc |= expected_addr_match(sa, &args->expected_raddr,
593 						 "remote");
594 		}
595 	} else {
596 		log_err_errno("getpeername failed");
597 	}
598 
599 	return rc;
600 }
601 
602 static int get_index_from_cmsg(struct msghdr *m)
603 {
604 	struct cmsghdr *cm;
605 	int ifindex = 0;
606 	char buf[64];
607 
608 	for (cm = (struct cmsghdr *)CMSG_FIRSTHDR(m);
609 	     m->msg_controllen != 0 && cm;
610 	     cm = (struct cmsghdr *)CMSG_NXTHDR(m, cm)) {
611 
612 		if (cm->cmsg_level == SOL_IP &&
613 		    cm->cmsg_type == IP_PKTINFO) {
614 			struct in_pktinfo *pi;
615 
616 			pi = (struct in_pktinfo *)(CMSG_DATA(cm));
617 			inet_ntop(AF_INET, &pi->ipi_addr, buf, sizeof(buf));
618 			ifindex = pi->ipi_ifindex;
619 		} else if (cm->cmsg_level == SOL_IPV6 &&
620 			   cm->cmsg_type == IPV6_PKTINFO) {
621 			struct in6_pktinfo *pi6;
622 
623 			pi6 = (struct in6_pktinfo *)(CMSG_DATA(cm));
624 			inet_ntop(AF_INET6, &pi6->ipi6_addr, buf, sizeof(buf));
625 			ifindex = pi6->ipi6_ifindex;
626 		}
627 	}
628 
629 	if (ifindex) {
630 		log_msg("    pktinfo: ifindex %d dest addr %s\n",
631 			ifindex, buf);
632 	}
633 	return ifindex;
634 }
635 
636 static int send_msg_no_cmsg(int sd, void *addr, socklen_t alen)
637 {
638 	int err;
639 
640 again:
641 	err = sendto(sd, msg, msglen, 0, addr, alen);
642 	if (err < 0) {
643 		if (errno == EACCES && try_broadcast) {
644 			try_broadcast = 0;
645 			if (!set_broadcast(sd))
646 				goto again;
647 			errno = EACCES;
648 		}
649 
650 		log_err_errno("sendto failed");
651 		return 1;
652 	}
653 
654 	return 0;
655 }
656 
657 static int send_msg_cmsg(int sd, void *addr, socklen_t alen,
658 			 int ifindex, int version)
659 {
660 	unsigned char cmsgbuf[64];
661 	struct iovec iov[2];
662 	struct cmsghdr *cm;
663 	struct msghdr m;
664 	int err;
665 
666 	iov[0].iov_base = msg;
667 	iov[0].iov_len = msglen;
668 	m.msg_iov = iov;
669 	m.msg_iovlen = 1;
670 	m.msg_name = (caddr_t)addr;
671 	m.msg_namelen = alen;
672 
673 	memset(cmsgbuf, 0, sizeof(cmsgbuf));
674 	cm = (struct cmsghdr *)cmsgbuf;
675 	m.msg_control = (caddr_t)cm;
676 
677 	if (version == AF_INET) {
678 		struct in_pktinfo *pi;
679 
680 		cm->cmsg_level = SOL_IP;
681 		cm->cmsg_type = IP_PKTINFO;
682 		cm->cmsg_len = CMSG_LEN(sizeof(struct in_pktinfo));
683 		pi = (struct in_pktinfo *)(CMSG_DATA(cm));
684 		pi->ipi_ifindex = ifindex;
685 
686 		m.msg_controllen = cm->cmsg_len;
687 
688 	} else if (version == AF_INET6) {
689 		struct in6_pktinfo *pi6;
690 
691 		cm->cmsg_level = SOL_IPV6;
692 		cm->cmsg_type = IPV6_PKTINFO;
693 		cm->cmsg_len = CMSG_LEN(sizeof(struct in6_pktinfo));
694 
695 		pi6 = (struct in6_pktinfo *)(CMSG_DATA(cm));
696 		pi6->ipi6_ifindex = ifindex;
697 
698 		m.msg_controllen = cm->cmsg_len;
699 	}
700 
701 again:
702 	err = sendmsg(sd, &m, 0);
703 	if (err < 0) {
704 		if (errno == EACCES && try_broadcast) {
705 			try_broadcast = 0;
706 			if (!set_broadcast(sd))
707 				goto again;
708 			errno = EACCES;
709 		}
710 
711 		log_err_errno("sendmsg failed");
712 		return 1;
713 	}
714 
715 	return 0;
716 }
717 
718 
719 static int send_msg(int sd, void *addr, socklen_t alen, struct sock_args *args)
720 {
721 	if (args->type == SOCK_STREAM) {
722 		if (write(sd, msg, msglen) < 0) {
723 			log_err_errno("write failed sending msg to peer");
724 			return 1;
725 		}
726 	} else if (args->ifindex && args->use_cmsg) {
727 		if (send_msg_cmsg(sd, addr, alen, args->ifindex, args->version))
728 			return 1;
729 	} else {
730 		if (send_msg_no_cmsg(sd, addr, alen))
731 			return 1;
732 	}
733 
734 	log_msg("Sent message:\n");
735 	log_msg("    %.24s%s\n", msg, msglen > 24 ? " ..." : "");
736 
737 	return 0;
738 }
739 
740 static int socket_read_dgram(int sd, struct sock_args *args)
741 {
742 	unsigned char addr[sizeof(struct sockaddr_in6)];
743 	struct sockaddr *sa = (struct sockaddr *) addr;
744 	socklen_t alen = sizeof(addr);
745 	struct iovec iov[2];
746 	struct msghdr m = {
747 		.msg_name = (caddr_t)addr,
748 		.msg_namelen = alen,
749 		.msg_iov = iov,
750 		.msg_iovlen = 1,
751 	};
752 	unsigned char cmsgbuf[256];
753 	struct cmsghdr *cm = (struct cmsghdr *)cmsgbuf;
754 	char buf[16*1024];
755 	int ifindex;
756 	int len;
757 
758 	iov[0].iov_base = (caddr_t)buf;
759 	iov[0].iov_len = sizeof(buf);
760 
761 	memset(cmsgbuf, 0, sizeof(cmsgbuf));
762 	m.msg_control = (caddr_t)cm;
763 	m.msg_controllen = sizeof(cmsgbuf);
764 
765 	len = recvmsg(sd, &m, 0);
766 	if (len == 0) {
767 		log_msg("peer closed connection.\n");
768 		return 0;
769 	} else if (len < 0) {
770 		log_msg("failed to read message: %d: %s\n",
771 			errno, strerror(errno));
772 		return -1;
773 	}
774 
775 	buf[len] = '\0';
776 
777 	log_address("Message from:", sa);
778 	log_msg("    %.24s%s\n", buf, len > 24 ? " ..." : "");
779 
780 	ifindex = get_index_from_cmsg(&m);
781 	if (args->expected_ifindex) {
782 		if (args->expected_ifindex != ifindex) {
783 			log_error("Device index mismatch: expected %d have %d\n",
784 				  args->expected_ifindex, ifindex);
785 			return -1;
786 		}
787 		log_msg("Device index matches: expected %d have %d\n",
788 			args->expected_ifindex, ifindex);
789 	}
790 
791 	if (!interactive && server_mode) {
792 		if (sa->sa_family == AF_INET6) {
793 			struct sockaddr_in6 *s6 = (struct sockaddr_in6 *) sa;
794 			struct in6_addr *in6 = &s6->sin6_addr;
795 
796 			if (IN6_IS_ADDR_V4MAPPED(in6)) {
797 				const uint32_t *pa = (uint32_t *) &in6->s6_addr;
798 				struct in_addr in4;
799 				struct sockaddr_in *sin;
800 
801 				sin = (struct sockaddr_in *) addr;
802 				pa += 3;
803 				in4.s_addr = *pa;
804 				sin->sin_addr = in4;
805 				sin->sin_family = AF_INET;
806 				if (send_msg_cmsg(sd, addr, alen,
807 						  ifindex, AF_INET) < 0)
808 					goto out_err;
809 			}
810 		}
811 again:
812 		iov[0].iov_len = len;
813 
814 		if (args->version == AF_INET6) {
815 			struct sockaddr_in6 *s6 = (struct sockaddr_in6 *) sa;
816 
817 			if (args->dev) {
818 				/* avoid PKTINFO conflicts with bindtodev */
819 				if (sendto(sd, buf, len, 0,
820 					   (void *) addr, alen) < 0)
821 					goto out_err;
822 			} else {
823 				/* kernel is allowing scope_id to be set to VRF
824 				 * index for LLA. for sends to global address
825 				 * reset scope id
826 				 */
827 				s6->sin6_scope_id = ifindex;
828 				if (sendmsg(sd, &m, 0) < 0)
829 					goto out_err;
830 			}
831 		} else {
832 			int err;
833 
834 			err = sendmsg(sd, &m, 0);
835 			if (err < 0) {
836 				if (errno == EACCES && try_broadcast) {
837 					try_broadcast = 0;
838 					if (!set_broadcast(sd))
839 						goto again;
840 					errno = EACCES;
841 				}
842 				goto out_err;
843 			}
844 		}
845 		log_msg("Sent message:\n");
846 		log_msg("    %.24s%s\n", buf, len > 24 ? " ..." : "");
847 	}
848 
849 	return 1;
850 out_err:
851 	log_err_errno("failed to send msg to peer");
852 	return -1;
853 }
854 
855 static int socket_read_stream(int sd)
856 {
857 	char buf[1024];
858 	int len;
859 
860 	len = read(sd, buf, sizeof(buf)-1);
861 	if (len == 0) {
862 		log_msg("client closed connection.\n");
863 		return 0;
864 	} else if (len < 0) {
865 		log_msg("failed to read message\n");
866 		return -1;
867 	}
868 
869 	buf[len] = '\0';
870 	log_msg("Incoming message:\n");
871 	log_msg("    %.24s%s\n", buf, len > 24 ? " ..." : "");
872 
873 	if (!interactive && server_mode) {
874 		if (write(sd, buf, len) < 0) {
875 			log_err_errno("failed to send buf");
876 			return -1;
877 		}
878 		log_msg("Sent message:\n");
879 		log_msg("     %.24s%s\n", buf, len > 24 ? " ..." : "");
880 	}
881 
882 	return 1;
883 }
884 
885 static int socket_read(int sd, struct sock_args *args)
886 {
887 	if (args->type == SOCK_STREAM)
888 		return socket_read_stream(sd);
889 
890 	return socket_read_dgram(sd, args);
891 }
892 
893 static int stdin_to_socket(int sd, int type, void *addr, socklen_t alen)
894 {
895 	char buf[1024];
896 	int len;
897 
898 	if (fgets(buf, sizeof(buf), stdin) == NULL)
899 		return 0;
900 
901 	len = strlen(buf);
902 	if (type == SOCK_STREAM) {
903 		if (write(sd, buf, len) < 0) {
904 			log_err_errno("failed to send buf");
905 			return -1;
906 		}
907 	} else {
908 		int err;
909 
910 again:
911 		err = sendto(sd, buf, len, 0, addr, alen);
912 		if (err < 0) {
913 			if (errno == EACCES && try_broadcast) {
914 				try_broadcast = 0;
915 				if (!set_broadcast(sd))
916 					goto again;
917 				errno = EACCES;
918 			}
919 			log_err_errno("failed to send msg to peer");
920 			return -1;
921 		}
922 	}
923 	log_msg("Sent message:\n");
924 	log_msg("    %.24s%s\n", buf, len > 24 ? " ..." : "");
925 
926 	return 1;
927 }
928 
929 static void set_recv_attr(int sd, int version)
930 {
931 	if (version == AF_INET6) {
932 		set_recvpktinfo_v6(sd);
933 		set_recverr_v6(sd);
934 	} else {
935 		set_pktinfo_v4(sd);
936 		set_recverr_v4(sd);
937 	}
938 }
939 
940 static int msg_loop(int client, int sd, void *addr, socklen_t alen,
941 		    struct sock_args *args)
942 {
943 	struct timeval timeout = { .tv_sec = prog_timeout }, *ptval = NULL;
944 	fd_set rfds;
945 	int nfds;
946 	int rc;
947 
948 	if (args->type != SOCK_STREAM)
949 		set_recv_attr(sd, args->version);
950 
951 	if (msg) {
952 		msglen = strlen(msg);
953 
954 		/* client sends first message */
955 		if (client) {
956 			if (send_msg(sd, addr, alen, args))
957 				return 1;
958 		}
959 		if (!interactive) {
960 			ptval = &timeout;
961 			if (!prog_timeout)
962 				timeout.tv_sec = 5;
963 		}
964 	}
965 
966 	nfds = interactive ? MAX(fileno(stdin), sd)  + 1 : sd + 1;
967 	while (1) {
968 		FD_ZERO(&rfds);
969 		FD_SET(sd, &rfds);
970 		if (interactive)
971 			FD_SET(fileno(stdin), &rfds);
972 
973 		rc = select(nfds, &rfds, NULL, NULL, ptval);
974 		if (rc < 0) {
975 			if (errno == EINTR)
976 				continue;
977 
978 			rc = 1;
979 			log_err_errno("select failed");
980 			break;
981 		} else if (rc == 0) {
982 			log_error("Timed out waiting for response\n");
983 			rc = 2;
984 			break;
985 		}
986 
987 		if (FD_ISSET(sd, &rfds)) {
988 			rc = socket_read(sd, args);
989 			if (rc < 0) {
990 				rc = 1;
991 				break;
992 			}
993 			if (rc == 0)
994 				break;
995 		}
996 
997 		rc = 0;
998 
999 		if (FD_ISSET(fileno(stdin), &rfds)) {
1000 			if (stdin_to_socket(sd, args->type, addr, alen) <= 0)
1001 				break;
1002 		}
1003 
1004 		if (interactive)
1005 			continue;
1006 
1007 		if (iter != -1) {
1008 			--iter;
1009 			if (iter == 0)
1010 				break;
1011 		}
1012 
1013 		log_msg("Going into quiet mode\n");
1014 		quiet = 1;
1015 
1016 		if (client) {
1017 			if (send_msg(sd, addr, alen, args)) {
1018 				rc = 1;
1019 				break;
1020 			}
1021 		}
1022 	}
1023 
1024 	return rc;
1025 }
1026 
1027 static int msock_init(struct sock_args *args, int server)
1028 {
1029 	uint32_t if_addr = htonl(INADDR_ANY);
1030 	struct sockaddr_in laddr = {
1031 		.sin_family = AF_INET,
1032 		.sin_port = htons(args->port),
1033 	};
1034 	int one = 1;
1035 	int sd;
1036 
1037 	if (!server && args->has_local_ip)
1038 		if_addr = args->local_addr.in.s_addr;
1039 
1040 	sd = socket(PF_INET, SOCK_DGRAM, 0);
1041 	if (sd < 0) {
1042 		log_err_errno("socket");
1043 		return -1;
1044 	}
1045 
1046 	if (setsockopt(sd, SOL_SOCKET, SO_REUSEADDR,
1047 		       (char *)&one, sizeof(one)) < 0) {
1048 		log_err_errno("Setting SO_REUSEADDR error");
1049 		goto out_err;
1050 	}
1051 
1052 	if (setsockopt(sd, SOL_SOCKET, SO_BROADCAST,
1053 		       (char *)&one, sizeof(one)) < 0)
1054 		log_err_errno("Setting SO_BROADCAST error");
1055 
1056 	if (args->dev && bind_to_device(sd, args->dev) != 0)
1057 		goto out_err;
1058 	else if (args->use_setsockopt &&
1059 		 set_multicast_if(sd, args->ifindex))
1060 		goto out_err;
1061 
1062 	laddr.sin_addr.s_addr = if_addr;
1063 
1064 	if (bind(sd, (struct sockaddr *) &laddr, sizeof(laddr)) < 0) {
1065 		log_err_errno("bind failed");
1066 		goto out_err;
1067 	}
1068 
1069 	if (server &&
1070 	    set_membership(sd, args->grp.s_addr,
1071 			   args->local_addr.in.s_addr, args->ifindex))
1072 		goto out_err;
1073 
1074 	return sd;
1075 out_err:
1076 	close(sd);
1077 	return -1;
1078 }
1079 
1080 static int msock_server(struct sock_args *args)
1081 {
1082 	return msock_init(args, 1);
1083 }
1084 
1085 static int msock_client(struct sock_args *args)
1086 {
1087 	return msock_init(args, 0);
1088 }
1089 
1090 static int bind_socket(int sd, struct sock_args *args)
1091 {
1092 	struct sockaddr_in serv_addr = {
1093 		.sin_family = AF_INET,
1094 	};
1095 	struct sockaddr_in6 serv6_addr = {
1096 		.sin6_family = AF_INET6,
1097 	};
1098 	void *addr;
1099 	socklen_t alen;
1100 
1101 	if (!args->has_local_ip && args->type == SOCK_RAW)
1102 		return 0;
1103 
1104 	switch (args->version) {
1105 	case AF_INET:
1106 		serv_addr.sin_port = htons(args->port);
1107 		serv_addr.sin_addr = args->local_addr.in;
1108 		addr = &serv_addr;
1109 		alen = sizeof(serv_addr);
1110 		break;
1111 
1112 	case AF_INET6:
1113 		serv6_addr.sin6_port = htons(args->port);
1114 		serv6_addr.sin6_addr = args->local_addr.in6;
1115 		addr = &serv6_addr;
1116 		alen = sizeof(serv6_addr);
1117 		break;
1118 
1119 	default:
1120 		log_error("Invalid address family\n");
1121 		return -1;
1122 	}
1123 
1124 	if (bind(sd, addr, alen) < 0) {
1125 		log_err_errno("error binding socket");
1126 		return -1;
1127 	}
1128 
1129 	return 0;
1130 }
1131 
1132 static int lsock_init(struct sock_args *args)
1133 {
1134 	long flags;
1135 	int sd;
1136 
1137 	sd = socket(args->version, args->type, args->protocol);
1138 	if (sd < 0) {
1139 		log_err_errno("Error opening socket");
1140 		return  -1;
1141 	}
1142 
1143 	if (set_reuseaddr(sd) != 0)
1144 		goto err;
1145 
1146 	if (set_reuseport(sd) != 0)
1147 		goto err;
1148 
1149 	if (args->dev && bind_to_device(sd, args->dev) != 0)
1150 		goto err;
1151 	else if (args->use_setsockopt &&
1152 		 set_unicast_if(sd, args->ifindex, args->version))
1153 		goto err;
1154 
1155 	if (bind_socket(sd, args))
1156 		goto err;
1157 
1158 	if (args->bind_test_only)
1159 		goto out;
1160 
1161 	if (args->type == SOCK_STREAM && listen(sd, 1) < 0) {
1162 		log_err_errno("listen failed");
1163 		goto err;
1164 	}
1165 
1166 	flags = fcntl(sd, F_GETFL);
1167 	if ((flags < 0) || (fcntl(sd, F_SETFL, flags|O_NONBLOCK) < 0)) {
1168 		log_err_errno("Failed to set non-blocking option");
1169 		goto err;
1170 	}
1171 
1172 	if (fcntl(sd, F_SETFD, FD_CLOEXEC) < 0)
1173 		log_err_errno("Failed to set close-on-exec flag");
1174 
1175 out:
1176 	return sd;
1177 
1178 err:
1179 	close(sd);
1180 	return -1;
1181 }
1182 
1183 static int do_server(struct sock_args *args)
1184 {
1185 	struct timeval timeout = { .tv_sec = prog_timeout }, *ptval = NULL;
1186 	unsigned char addr[sizeof(struct sockaddr_in6)] = {};
1187 	socklen_t alen = sizeof(addr);
1188 	int lsd, csd = -1;
1189 
1190 	fd_set rfds;
1191 	int rc;
1192 
1193 	if (prog_timeout)
1194 		ptval = &timeout;
1195 
1196 	if (args->has_grp)
1197 		lsd = msock_server(args);
1198 	else
1199 		lsd = lsock_init(args);
1200 
1201 	if (lsd < 0)
1202 		return 1;
1203 
1204 	if (args->bind_test_only) {
1205 		close(lsd);
1206 		return 0;
1207 	}
1208 
1209 	if (args->type != SOCK_STREAM) {
1210 		rc = msg_loop(0, lsd, (void *) addr, alen, args);
1211 		close(lsd);
1212 		return rc;
1213 	}
1214 
1215 	if (args->password && tcp_md5_remote(lsd, args)) {
1216 		close(lsd);
1217 		return 1;
1218 	}
1219 
1220 	while (1) {
1221 		log_msg("\n");
1222 		log_msg("waiting for client connection.\n");
1223 		FD_ZERO(&rfds);
1224 		FD_SET(lsd, &rfds);
1225 
1226 		rc = select(lsd+1, &rfds, NULL, NULL, ptval);
1227 		if (rc == 0) {
1228 			rc = 2;
1229 			break;
1230 		}
1231 
1232 		if (rc < 0) {
1233 			if (errno == EINTR)
1234 				continue;
1235 
1236 			log_err_errno("select failed");
1237 			break;
1238 		}
1239 
1240 		if (FD_ISSET(lsd, &rfds)) {
1241 
1242 			csd = accept(lsd, (void *) addr, &alen);
1243 			if (csd < 0) {
1244 				log_err_errno("accept failed");
1245 				break;
1246 			}
1247 
1248 			rc = show_sockstat(csd, args);
1249 			if (rc)
1250 				break;
1251 
1252 			rc = check_device(csd, args);
1253 			if (rc)
1254 				break;
1255 		}
1256 
1257 		rc = msg_loop(0, csd, (void *) addr, alen, args);
1258 		close(csd);
1259 
1260 		if (!interactive)
1261 			break;
1262 	}
1263 
1264 	close(lsd);
1265 
1266 	return rc;
1267 }
1268 
1269 static int wait_for_connect(int sd)
1270 {
1271 	struct timeval _tv = { .tv_sec = prog_timeout }, *tv = NULL;
1272 	fd_set wfd;
1273 	int val = 0, sz = sizeof(val);
1274 	int rc;
1275 
1276 	FD_ZERO(&wfd);
1277 	FD_SET(sd, &wfd);
1278 
1279 	if (prog_timeout)
1280 		tv = &_tv;
1281 
1282 	rc = select(FD_SETSIZE, NULL, &wfd, NULL, tv);
1283 	if (rc == 0) {
1284 		log_error("connect timed out\n");
1285 		return -2;
1286 	} else if (rc < 0) {
1287 		log_err_errno("select failed");
1288 		return -3;
1289 	}
1290 
1291 	if (getsockopt(sd, SOL_SOCKET, SO_ERROR, &val, (socklen_t *)&sz) < 0) {
1292 		log_err_errno("getsockopt(SO_ERROR) failed");
1293 		return -4;
1294 	}
1295 
1296 	if (val != 0) {
1297 		log_error("connect failed: %d: %s\n", val, strerror(val));
1298 		return -1;
1299 	}
1300 
1301 	return 0;
1302 }
1303 
1304 static int connectsock(void *addr, socklen_t alen, struct sock_args *args)
1305 {
1306 	int sd, rc = -1;
1307 	long flags;
1308 
1309 	sd = socket(args->version, args->type, args->protocol);
1310 	if (sd < 0) {
1311 		log_err_errno("Failed to create socket");
1312 		return -1;
1313 	}
1314 
1315 	flags = fcntl(sd, F_GETFL);
1316 	if ((flags < 0) || (fcntl(sd, F_SETFL, flags|O_NONBLOCK) < 0)) {
1317 		log_err_errno("Failed to set non-blocking option");
1318 		goto err;
1319 	}
1320 
1321 	if (set_reuseport(sd) != 0)
1322 		goto err;
1323 
1324 	if (args->dev && bind_to_device(sd, args->dev) != 0)
1325 		goto err;
1326 	else if (args->use_setsockopt &&
1327 		 set_unicast_if(sd, args->ifindex, args->version))
1328 		goto err;
1329 
1330 	if (args->has_local_ip && bind_socket(sd, args))
1331 		goto err;
1332 
1333 	if (args->type != SOCK_STREAM)
1334 		goto out;
1335 
1336 	if (args->password && tcp_md5sig(sd, addr, alen, args))
1337 		goto err;
1338 
1339 	if (args->bind_test_only)
1340 		goto out;
1341 
1342 	if (connect(sd, addr, alen) < 0) {
1343 		if (errno != EINPROGRESS) {
1344 			log_err_errno("Failed to connect to remote host");
1345 			rc = -1;
1346 			goto err;
1347 		}
1348 		rc = wait_for_connect(sd);
1349 		if (rc < 0)
1350 			goto err;
1351 	}
1352 out:
1353 	return sd;
1354 
1355 err:
1356 	close(sd);
1357 	return rc;
1358 }
1359 
1360 static int do_client(struct sock_args *args)
1361 {
1362 	struct sockaddr_in sin = {
1363 		.sin_family = AF_INET,
1364 	};
1365 	struct sockaddr_in6 sin6 = {
1366 		.sin6_family = AF_INET6,
1367 	};
1368 	void *addr;
1369 	int alen;
1370 	int rc = 0;
1371 	int sd;
1372 
1373 	if (!args->has_remote_ip && !args->has_grp) {
1374 		fprintf(stderr, "remote IP or multicast group not given\n");
1375 		return 1;
1376 	}
1377 
1378 	switch (args->version) {
1379 	case AF_INET:
1380 		sin.sin_port = htons(args->port);
1381 		if (args->has_grp)
1382 			sin.sin_addr = args->grp;
1383 		else
1384 			sin.sin_addr = args->remote_addr.in;
1385 		addr = &sin;
1386 		alen = sizeof(sin);
1387 		break;
1388 	case AF_INET6:
1389 		sin6.sin6_port = htons(args->port);
1390 		sin6.sin6_addr = args->remote_addr.in6;
1391 		sin6.sin6_scope_id = args->scope_id;
1392 		addr = &sin6;
1393 		alen = sizeof(sin6);
1394 		break;
1395 	}
1396 
1397 	if (args->has_grp)
1398 		sd = msock_client(args);
1399 	else
1400 		sd = connectsock(addr, alen, args);
1401 
1402 	if (sd < 0)
1403 		return -sd;
1404 
1405 	if (args->bind_test_only)
1406 		goto out;
1407 
1408 	if (args->type == SOCK_STREAM) {
1409 		rc = show_sockstat(sd, args);
1410 		if (rc != 0)
1411 			goto out;
1412 	}
1413 
1414 	rc = msg_loop(1, sd, addr, alen, args);
1415 
1416 out:
1417 	close(sd);
1418 
1419 	return rc;
1420 }
1421 
1422 enum addr_type {
1423 	ADDR_TYPE_LOCAL,
1424 	ADDR_TYPE_REMOTE,
1425 	ADDR_TYPE_MCAST,
1426 	ADDR_TYPE_EXPECTED_LOCAL,
1427 	ADDR_TYPE_EXPECTED_REMOTE,
1428 	ADDR_TYPE_MD5_PREFIX,
1429 };
1430 
1431 static int convert_addr(struct sock_args *args, const char *_str,
1432 			enum addr_type atype)
1433 {
1434 	int pfx_len_max = args->version == AF_INET6 ? 128 : 32;
1435 	int family = args->version;
1436 	char *str, *dev, *sep;
1437 	struct in6_addr *in6;
1438 	struct in_addr  *in;
1439 	const char *desc;
1440 	void *addr;
1441 	int rc = 0;
1442 
1443 	str = strdup(_str);
1444 	if (!str)
1445 		return -ENOMEM;
1446 
1447 	switch (atype) {
1448 	case ADDR_TYPE_LOCAL:
1449 		desc = "local";
1450 		addr = &args->local_addr;
1451 		break;
1452 	case ADDR_TYPE_REMOTE:
1453 		desc = "remote";
1454 		addr = &args->remote_addr;
1455 		break;
1456 	case ADDR_TYPE_MCAST:
1457 		desc = "mcast grp";
1458 		addr = &args->grp;
1459 		break;
1460 	case ADDR_TYPE_EXPECTED_LOCAL:
1461 		desc = "expected local";
1462 		addr = &args->expected_laddr;
1463 		break;
1464 	case ADDR_TYPE_EXPECTED_REMOTE:
1465 		desc = "expected remote";
1466 		addr = &args->expected_raddr;
1467 		break;
1468 	case ADDR_TYPE_MD5_PREFIX:
1469 		desc = "md5 prefix";
1470 		if (family == AF_INET) {
1471 			args->md5_prefix.v4.sin_family = AF_INET;
1472 			addr = &args->md5_prefix.v4.sin_addr;
1473 		} else if (family == AF_INET6) {
1474 			args->md5_prefix.v6.sin6_family = AF_INET6;
1475 			addr = &args->md5_prefix.v6.sin6_addr;
1476 		} else
1477 			return 1;
1478 
1479 		sep = strchr(str, '/');
1480 		if (sep) {
1481 			*sep = '\0';
1482 			sep++;
1483 			if (str_to_uint(sep, 1, pfx_len_max,
1484 					&args->prefix_len) != 0) {
1485 				fprintf(stderr, "Invalid port\n");
1486 				return 1;
1487 			}
1488 		} else {
1489 			args->prefix_len = pfx_len_max;
1490 		}
1491 		break;
1492 	default:
1493 		log_error("unknown address type");
1494 		exit(1);
1495 	}
1496 
1497 	switch (family) {
1498 	case AF_INET:
1499 		in  = (struct in_addr *) addr;
1500 		if (str) {
1501 			if (inet_pton(AF_INET, str, in) == 0) {
1502 				log_error("Invalid %s IP address\n", desc);
1503 				rc = -1;
1504 				goto out;
1505 			}
1506 		} else {
1507 			in->s_addr = htonl(INADDR_ANY);
1508 		}
1509 		break;
1510 
1511 	case AF_INET6:
1512 		dev = strchr(str, '%');
1513 		if (dev) {
1514 			*dev = '\0';
1515 			dev++;
1516 		}
1517 
1518 		in6 = (struct in6_addr *) addr;
1519 		if (str) {
1520 			if (inet_pton(AF_INET6, str, in6) == 0) {
1521 				log_error("Invalid %s IPv6 address\n", desc);
1522 				rc = -1;
1523 				goto out;
1524 			}
1525 		} else {
1526 			*in6 = in6addr_any;
1527 		}
1528 		if (dev) {
1529 			args->scope_id = get_ifidx(dev);
1530 			if (args->scope_id < 0) {
1531 				log_error("Invalid scope on %s IPv6 address\n",
1532 					  desc);
1533 				rc = -1;
1534 				goto out;
1535 			}
1536 		}
1537 		break;
1538 
1539 	default:
1540 		log_error("Invalid address family\n");
1541 	}
1542 
1543 out:
1544 	free(str);
1545 	return rc;
1546 }
1547 
1548 static char *random_msg(int len)
1549 {
1550 	int i, n = 0, olen = len + 1;
1551 	char *m;
1552 
1553 	if (len <= 0)
1554 		return NULL;
1555 
1556 	m = malloc(olen);
1557 	if (!m)
1558 		return NULL;
1559 
1560 	while (len > 26) {
1561 		i = snprintf(m + n, olen - n, "%.26s",
1562 			     "abcdefghijklmnopqrstuvwxyz");
1563 		n += i;
1564 		len -= i;
1565 	}
1566 	i = snprintf(m + n, olen - n, "%.*s", len,
1567 		     "abcdefghijklmnopqrstuvwxyz");
1568 	return m;
1569 }
1570 
1571 #define GETOPT_STR  "sr:l:p:t:g:P:DRn:M:m:d:SCi6L:0:1:2:Fbq"
1572 
1573 static void print_usage(char *prog)
1574 {
1575 	printf(
1576 	"usage: %s OPTS\n"
1577 	"Required:\n"
1578 	"    -r addr       remote address to connect to (client mode only)\n"
1579 	"    -p port       port to connect to (client mode)/listen on (server mode)\n"
1580 	"                  (default: %d)\n"
1581 	"    -s            server mode (default: client mode)\n"
1582 	"    -t            timeout seconds (default: none)\n"
1583 	"\n"
1584 	"Optional:\n"
1585 	"    -F            Restart server loop\n"
1586 	"    -6            IPv6 (default is IPv4)\n"
1587 	"    -P proto      protocol for socket: icmp, ospf (default: none)\n"
1588 	"    -D|R          datagram (D) / raw (R) socket (default stream)\n"
1589 	"    -l addr       local address to bind to\n"
1590 	"\n"
1591 	"    -d dev        bind socket to given device name\n"
1592 	"    -S            use setsockopt (IP_UNICAST_IF or IP_MULTICAST_IF)\n"
1593 	"                  to set device binding\n"
1594 	"    -C            use cmsg and IP_PKTINFO to specify device binding\n"
1595 	"\n"
1596 	"    -L len        send random message of given length\n"
1597 	"    -n num        number of times to send message\n"
1598 	"\n"
1599 	"    -M password   use MD5 sum protection\n"
1600 	"    -m prefix/len prefix and length to use for MD5 key\n"
1601 	"    -g grp        multicast group (e.g., 239.1.1.1)\n"
1602 	"    -i            interactive mode (default is echo and terminate)\n"
1603 	"\n"
1604 	"    -0 addr       Expected local address\n"
1605 	"    -1 addr       Expected remote address\n"
1606 	"    -2 dev        Expected device name (or index) to receive packet\n"
1607 	"\n"
1608 	"    -b            Bind test only.\n"
1609 	"    -q            Be quiet. Run test without printing anything.\n"
1610 	, prog, DEFAULT_PORT);
1611 }
1612 
1613 int main(int argc, char *argv[])
1614 {
1615 	struct sock_args args = {
1616 		.version = AF_INET,
1617 		.type    = SOCK_STREAM,
1618 		.port    = DEFAULT_PORT,
1619 	};
1620 	struct protoent *pe;
1621 	unsigned int tmp;
1622 	int forever = 0;
1623 
1624 	/* process inputs */
1625 	extern char *optarg;
1626 	int rc = 0;
1627 
1628 	/*
1629 	 * process input args
1630 	 */
1631 
1632 	while ((rc = getopt(argc, argv, GETOPT_STR)) != -1) {
1633 		switch (rc) {
1634 		case 's':
1635 			server_mode = 1;
1636 			break;
1637 		case 'F':
1638 			forever = 1;
1639 			break;
1640 		case 'l':
1641 			args.has_local_ip = 1;
1642 			if (convert_addr(&args, optarg, ADDR_TYPE_LOCAL) < 0)
1643 				return 1;
1644 			break;
1645 		case 'r':
1646 			args.has_remote_ip = 1;
1647 			if (convert_addr(&args, optarg, ADDR_TYPE_REMOTE) < 0)
1648 				return 1;
1649 			break;
1650 		case 'p':
1651 			if (str_to_uint(optarg, 1, 65535, &tmp) != 0) {
1652 				fprintf(stderr, "Invalid port\n");
1653 				return 1;
1654 			}
1655 			args.port = (unsigned short) tmp;
1656 			break;
1657 		case 't':
1658 			if (str_to_uint(optarg, 0, INT_MAX,
1659 					&prog_timeout) != 0) {
1660 				fprintf(stderr, "Invalid timeout\n");
1661 				return 1;
1662 			}
1663 			break;
1664 		case 'D':
1665 			args.type = SOCK_DGRAM;
1666 			break;
1667 		case 'R':
1668 			args.type = SOCK_RAW;
1669 			args.port = 0;
1670 			if (!args.protocol)
1671 				args.protocol = IPPROTO_RAW;
1672 			break;
1673 		case 'P':
1674 			pe = getprotobyname(optarg);
1675 			if (pe) {
1676 				args.protocol = pe->p_proto;
1677 			} else {
1678 				if (str_to_uint(optarg, 0, 0xffff, &tmp) != 0) {
1679 					fprintf(stderr, "Invalid protocol\n");
1680 					return 1;
1681 				}
1682 				args.protocol = tmp;
1683 			}
1684 			break;
1685 		case 'n':
1686 			iter = atoi(optarg);
1687 			break;
1688 		case 'L':
1689 			msg = random_msg(atoi(optarg));
1690 			break;
1691 		case 'M':
1692 			args.password = optarg;
1693 			break;
1694 		case 'm':
1695 			if (convert_addr(&args, optarg, ADDR_TYPE_MD5_PREFIX) < 0)
1696 				return 1;
1697 			break;
1698 		case 'S':
1699 			args.use_setsockopt = 1;
1700 			break;
1701 		case 'C':
1702 			args.use_cmsg = 1;
1703 			break;
1704 		case 'd':
1705 			args.dev = optarg;
1706 			args.ifindex = get_ifidx(optarg);
1707 			if (args.ifindex < 0) {
1708 				fprintf(stderr, "Invalid device name\n");
1709 				return 1;
1710 			}
1711 			break;
1712 		case 'i':
1713 			interactive = 1;
1714 			break;
1715 		case 'g':
1716 			args.has_grp = 1;
1717 			if (convert_addr(&args, optarg, ADDR_TYPE_MCAST) < 0)
1718 				return 1;
1719 			args.type = SOCK_DGRAM;
1720 			break;
1721 		case '6':
1722 			args.version = AF_INET6;
1723 			break;
1724 		case 'b':
1725 			args.bind_test_only = 1;
1726 			break;
1727 		case '0':
1728 			args.has_expected_laddr = 1;
1729 			if (convert_addr(&args, optarg,
1730 					 ADDR_TYPE_EXPECTED_LOCAL))
1731 				return 1;
1732 			break;
1733 		case '1':
1734 			args.has_expected_raddr = 1;
1735 			if (convert_addr(&args, optarg,
1736 					 ADDR_TYPE_EXPECTED_REMOTE))
1737 				return 1;
1738 
1739 			break;
1740 		case '2':
1741 			if (str_to_uint(optarg, 0, INT_MAX, &tmp) == 0) {
1742 				args.expected_ifindex = (int)tmp;
1743 			} else {
1744 				args.expected_ifindex = get_ifidx(optarg);
1745 				if (args.expected_ifindex < 0) {
1746 					fprintf(stderr,
1747 						"Invalid expected device\n");
1748 					return 1;
1749 				}
1750 			}
1751 			break;
1752 		case 'q':
1753 			quiet = 1;
1754 			break;
1755 		default:
1756 			print_usage(argv[0]);
1757 			return 1;
1758 		}
1759 	}
1760 
1761 	if (args.password &&
1762 	    ((!args.has_remote_ip && !args.prefix_len) || args.type != SOCK_STREAM)) {
1763 		log_error("MD5 passwords apply to TCP only and require a remote ip for the password\n");
1764 		return 1;
1765 	}
1766 
1767 	if (args.prefix_len && !args.password) {
1768 		log_error("Prefix range for MD5 protection specified without a password\n");
1769 		return 1;
1770 	}
1771 
1772 	if ((args.use_setsockopt || args.use_cmsg) && !args.ifindex) {
1773 		fprintf(stderr, "Device binding not specified\n");
1774 		return 1;
1775 	}
1776 	if (args.use_setsockopt || args.use_cmsg)
1777 		args.dev = NULL;
1778 
1779 	if (iter == 0) {
1780 		fprintf(stderr, "Invalid number of messages to send\n");
1781 		return 1;
1782 	}
1783 
1784 	if (args.type == SOCK_STREAM && !args.protocol)
1785 		args.protocol = IPPROTO_TCP;
1786 	if (args.type == SOCK_DGRAM && !args.protocol)
1787 		args.protocol = IPPROTO_UDP;
1788 
1789 	if ((args.type == SOCK_STREAM || args.type == SOCK_DGRAM) &&
1790 	     args.port == 0) {
1791 		fprintf(stderr, "Invalid port number\n");
1792 		return 1;
1793 	}
1794 
1795 	if (!server_mode && !args.has_grp &&
1796 	    !args.has_remote_ip && !args.has_local_ip) {
1797 		fprintf(stderr,
1798 			"Local (server mode) or remote IP (client IP) required\n");
1799 		return 1;
1800 	}
1801 
1802 	if (interactive) {
1803 		prog_timeout = 0;
1804 		msg = NULL;
1805 	}
1806 
1807 	if (server_mode) {
1808 		do {
1809 			rc = do_server(&args);
1810 		} while (forever);
1811 
1812 		return rc;
1813 	}
1814 	return do_client(&args);
1815 }
1816