xref: /netbsd-src/sbin/ping6/ping6.c (revision bdc22b2e01993381dcefeff2bc9b56ca75a4235c)
1 /*	$NetBSD: ping6.c,v 1.103 2018/04/24 07:22:32 maxv Exp $	*/
2 /*	$KAME: ping6.c,v 1.164 2002/11/16 14:05:37 itojun Exp $	*/
3 
4 /*
5  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. Neither the name of the project nor the names of its contributors
17  *    may be used to endorse or promote products derived from this software
18  *    without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  */
32 
33 /*	BSDI	ping.c,v 2.3 1996/01/21 17:56:50 jch Exp	*/
34 
35 /*
36  * Copyright (c) 1989, 1993
37  *	The Regents of the University of California.  All rights reserved.
38  *
39  * This code is derived from software contributed to Berkeley by
40  * Mike Muuss.
41  *
42  * Redistribution and use in source and binary forms, with or without
43  * modification, are permitted provided that the following conditions
44  * are met:
45  * 1. Redistributions of source code must retain the above copyright
46  *    notice, this list of conditions and the following disclaimer.
47  * 2. Redistributions in binary form must reproduce the above copyright
48  *    notice, this list of conditions and the following disclaimer in the
49  *    documentation and/or other materials provided with the distribution.
50  * 3. Neither the name of the University nor the names of its contributors
51  *    may be used to endorse or promote products derived from this software
52  *    without specific prior written permission.
53  *
54  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
55  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
56  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
57  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
58  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
59  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
60  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
61  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
62  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
63  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
64  * SUCH DAMAGE.
65  */
66 
67 #if 0
68 #ifndef lint
69 static char copyright[] =
70 "@(#) Copyright (c) 1989, 1993\n\
71 	The Regents of the University of California.  All rights reserved.\n";
72 #endif /* not lint */
73 
74 #ifndef lint
75 static char sccsid[] = "@(#)ping.c	8.1 (Berkeley) 6/5/93";
76 #endif /* not lint */
77 #else
78 #include <sys/cdefs.h>
79 #ifndef lint
80 __RCSID("$NetBSD: ping6.c,v 1.103 2018/04/24 07:22:32 maxv Exp $");
81 #endif
82 #endif
83 
84 /*
85  * Using the InterNet Control Message Protocol (ICMP) "ECHO" facility,
86  * measure round-trip-delays and packet loss across network paths.
87  *
88  * Author -
89  *	Mike Muuss
90  *	U. S. Army Ballistic Research Laboratory
91  *	December, 1983
92  *
93  * Status -
94  *	Public Domain.  Distribution Unlimited.
95  * Bugs -
96  *	More statistics could always be gathered.
97  *	This program has to run SUID to ROOT to access the ICMP socket.
98  */
99 /*
100  * NOTE:
101  * USE_SIN6_SCOPE_ID assumes that sin6_scope_id has the same semantics
102  * as IPV6_PKTINFO.  Some people object it (sin6_scope_id specifies *link*
103  * while IPV6_PKTINFO specifies *interface*.  Link is defined as collection of
104  * network attached to 1 or more interfaces)
105  */
106 
107 #include <sys/param.h>
108 #include <sys/uio.h>
109 #include <sys/socket.h>
110 #include <sys/time.h>
111 
112 #include <net/if.h>
113 #include <net/route.h>
114 
115 #include <netinet/in.h>
116 #include <netinet/ip6.h>
117 #include <netinet/icmp6.h>
118 #include <arpa/inet.h>
119 #include <arpa/nameser.h>
120 #include <netdb.h>
121 
122 #include <ctype.h>
123 #include <err.h>
124 #include <errno.h>
125 #include <fcntl.h>
126 #include <math.h>
127 #include <signal.h>
128 #include <stdbool.h>
129 #include <stdio.h>
130 #include <stdlib.h>
131 #include <string.h>
132 #include <unistd.h>
133 #include <poll.h>
134 
135 #ifdef IPSEC
136 #include <netipsec/ipsec.h>
137 #endif
138 
139 #include <md5.h>
140 
141 #include "prog_ops.h"
142 
143 struct tv32 {
144 	u_int32_t tv32_sec;
145 	u_int32_t tv32_usec;
146 };
147 
148 #define MAXPACKETLEN	131072
149 #define	IP6LEN		40
150 #define ICMP6ECHOLEN	8	/* icmp echo header len excluding time */
151 #define ICMP6ECHOTMLEN sizeof(struct tv32)
152 #define ICMP6_NIQLEN	(ICMP6ECHOLEN + 8)
153 /* FQDN case, 64 bits of nonce + 32 bits ttl */
154 #define ICMP6_NIRLEN	(ICMP6ECHOLEN + 12)
155 #define	EXTRA		256	/* for AH and various other headers. weird. */
156 #define	DEFDATALEN	ICMP6ECHOTMLEN
157 #define MAXDATALEN	MAXPACKETLEN - IP6LEN - ICMP6ECHOLEN
158 #define	NROUTES		9		/* number of record route slots */
159 
160 #define	A(bit)		rcvd_tbl[(bit)>>3]	/* identify byte in array */
161 #define	B(bit)		(1 << ((bit) & 0x07))	/* identify bit in byte */
162 #define	SET(bit)	(A(bit) |= B(bit))
163 #define	CLR(bit)	(A(bit) &= (~B(bit)))
164 #define	TST(bit)	(A(bit) & B(bit))
165 
166 #define	F_FLOOD		0x0001
167 #define	F_INTERVAL	0x0002
168 #define	F_PINGFILLED	0x0008
169 #define	F_QUIET		0x0010
170 #define	F_SO_DEBUG	0x0040
171 #define	F_VERBOSE	0x0100
172 #if defined(IPSEC) && defined(IPSEC_POLICY_IPSEC)
173 #define	F_POLICY	0x0400
174 #endif
175 #define F_NODEADDR	0x0800
176 #define F_FQDN		0x1000
177 #define F_INTERFACE	0x2000
178 #define F_SRCADDR	0x4000
179 #define F_HOSTNAME	0x10000
180 #define F_FQDNOLD	0x20000
181 #define F_NIGROUP	0x40000
182 #define F_SUPTYPES	0x80000
183 #define F_ONCE		0x200000
184 #define F_NOUSERDATA	(F_NODEADDR | F_FQDN | F_FQDNOLD | F_SUPTYPES)
185 static u_int options;
186 
187 #define DUMMY_PORT	10101
188 
189 /*
190  * MAX_DUP_CHK is the number of bits in received table, i.e. the maximum
191  * number of received sequence numbers we can keep track of.  Change 128
192  * to 8192 for complete accuracy...
193  */
194 #define	MAX_DUP_CHK	(8 * 8192)
195 static int mx_dup_ck = MAX_DUP_CHK;
196 static char rcvd_tbl[MAX_DUP_CHK / 8];
197 
198 static struct addrinfo *res;
199 static struct sockaddr_in6 dst;	/* who to ping6 */
200 static struct sockaddr_in6 src;	/* src addr of this packet */
201 static socklen_t srclen;
202 static int datalen = DEFDATALEN;
203 static int s;				/* socket file descriptor */
204 static u_char outpack[MAXPACKETLEN];
205 static char BSPACE = '\b';		/* characters written for flood */
206 static char DOT = '.';
207 static char *hostname;
208 static int ident;			/* process id to identify our packets */
209 static u_int8_t nonce[8];		/* nonce field for node information */
210 static int hoplimit = -1;		/* hoplimit */
211 
212 /* counters */
213 static long npackets;			/* max packets to transmit */
214 static long nreceived;			/* # of packets we got back */
215 static long nrepeats;			/* number of duplicates */
216 static long ntransmitted;		/* sequence # for outbound packets = #sent */
217 static struct timespec interval = {1, 0}; /* interval between packets */
218 
219 static struct timespec now, last_tx, next_tx, first_tx;
220 static int lastrcvd = 1;			/* last ping sent has been received */
221 
222 /* timing */
223 static int timing;			/* flag to do timing */
224 static double tmin = 999999999.0;	/* minimum round trip time */
225 static double tmax = 0.0;		/* maximum round trip time */
226 static double tsum = 0.0;		/* sum of all times, for doing average */
227 static double tsumsq = 0.0;		/* sum of all times squared, for std. dev. */
228 static double maxwait = 0.0;		/* maxwait for reply in ms */
229 static double deadline = 0.0;		/* max running time in seconds */
230 
231 /* for node addresses */
232 static u_short naflags;
233 
234 /* for ancillary data(advanced API) */
235 static struct msghdr smsghdr;
236 static struct iovec smsgiov;
237 static char *scmsg = 0;
238 
239 static volatile sig_atomic_t seenint;
240 #ifdef SIGINFO
241 static volatile sig_atomic_t seeninfo;
242 #endif
243 
244 __dead static void	doit(u_char *, u_int);
245 static void	 fill(char *, char *);
246 static int	 get_hoplim(struct msghdr *);
247 static int	 get_pathmtu(struct msghdr *);
248 static struct in6_pktinfo *get_rcvpktinfo(struct msghdr *);
249 static void	 onsignal(int);
250 __dead static void	 onsigexit(int);
251 static size_t	 pingerlen(void);
252 static void	 pinger(void);
253 static const char *pr_addr(struct sockaddr *, int);
254 static void	 pr_icmph(struct icmp6_hdr *, u_char *);
255 static void	 pr_iph(struct ip6_hdr *);
256 static void	 pr_suptypes(struct icmp6_nodeinfo *, size_t);
257 static void	 pr_nodeaddr(struct icmp6_nodeinfo *, int);
258 static int	 myechoreply(const struct icmp6_hdr *);
259 static int	 mynireply(const struct icmp6_nodeinfo *);
260 static char *dnsdecode(const u_char **, const u_char *, const u_char *,
261 	char *, size_t);
262 static void	 pr_pack(u_char *, int, struct msghdr *);
263 static void	 pr_exthdrs(struct msghdr *);
264 static void	 pr_ip6opt(void *);
265 static void	 pr_rthdr(void *);
266 static int	 pr_bitrange(u_int32_t, int, int);
267 static void	 pr_retip(struct ip6_hdr *, u_char *);
268 static void	 summary(void);
269 static void	 tvsub(struct timeval *, struct timeval *);
270 #if defined(IPSEC) && defined(IPSEC_POLICY_IPSEC)
271 static int	 setpolicy(int, char *);
272 #endif
273 static char	*nigroup(char *);
274 static double	timespec_to_sec(const struct timespec *tp);
275 static double	diffsec(struct timespec *, struct timespec *);
276 __dead static void	 usage(void);
277 
278 int
279 main(int argc, char *argv[])
280 {
281 	struct addrinfo hints;
282 	u_int i, packlen;
283 	long l;
284 	int ch, hold, preload, optval, ret_ga;
285 	u_char *datap, *packet;
286 	char *e, *target, *ifname = NULL, *gateway = NULL;
287 	int ip6optlen = 0;
288 	struct cmsghdr *scmsgp = NULL;
289 	u_long lsockbufsize;
290 	int sockbufsize = 0;
291 	int usepktinfo = 0;
292 	struct in6_pktinfo *pktinfo = NULL;
293 	struct ip6_rthdr *rthdr = NULL;
294 #ifdef IPSEC_POLICY_IPSEC
295 	char *policy_in = NULL;
296 	char *policy_out = NULL;
297 #endif
298 	double intval;
299 	int mflag = 0;
300 
301 	/* just to be sure */
302 	memset(&smsghdr, 0, sizeof(smsghdr));
303 	memset(&smsgiov, 0, sizeof(smsgiov));
304 
305 	preload = 0;
306 	datap = &outpack[ICMP6ECHOLEN + ICMP6ECHOTMLEN];
307 
308 #if defined(IPSEC) && defined(IPSEC_POLICY_IPSEC)
309 #define ADDOPTS	"P:"
310 #else
311 #define ADDOPTS
312 #endif
313 
314 	if (prog_init && prog_init() == -1)
315 		err(EXIT_FAILURE, "init failed");
316 
317 	while ((ch = getopt(argc, argv,
318 	    "a:b:c:dfHg:h:I:i:l:mnNop:qS:s:tvwWx:X:" ADDOPTS)) != -1) {
319 #undef ADDOPTS
320 		switch (ch) {
321 		case 'a':
322 		{
323 			char *cp;
324 
325 			options &= ~F_NOUSERDATA;
326 			options |= F_NODEADDR;
327 			for (cp = optarg; *cp != '\0'; cp++) {
328 				switch (*cp) {
329 				case 'a':
330 					naflags |= NI_NODEADDR_FLAG_ALL;
331 					break;
332 				case 'c':
333 				case 'C':
334 					naflags |= NI_NODEADDR_FLAG_COMPAT;
335 					break;
336 				case 'l':
337 				case 'L':
338 					naflags |= NI_NODEADDR_FLAG_LINKLOCAL;
339 					break;
340 				case 's':
341 				case 'S':
342 					naflags |= NI_NODEADDR_FLAG_SITELOCAL;
343 					break;
344 				case 'g':
345 				case 'G':
346 					naflags |= NI_NODEADDR_FLAG_GLOBAL;
347 					break;
348 				case 'A': /* experimental. not in the spec */
349 #ifdef NI_NODEADDR_FLAG_ANYCAST
350 					naflags |= NI_NODEADDR_FLAG_ANYCAST;
351 					break;
352 #else
353 					errx(1,
354 "-a A is not supported on the platform");
355 					/*NOTREACHED*/
356 #endif
357 				default:
358 					usage();
359 					/*NOTREACHED*/
360 				}
361 			}
362 			break;
363 		}
364 		case 'b':
365 			errno = 0;
366 			e = NULL;
367 			lsockbufsize = strtoul(optarg, &e, 10);
368 			sockbufsize = lsockbufsize;
369 			if (errno || !*optarg || *e ||
370 			    (u_long)sockbufsize != lsockbufsize)
371 				errx(1, "invalid socket buffer size");
372 			break;
373 		case 'c':
374 			l = strtol(optarg, &e, 10);
375 			if (l <= 0 || *optarg == '\0' || *e != '\0')
376 				errx(1,
377 				    "illegal number of packets -- %s", optarg);
378 #if INT_MAX < LONG_MAX
379 			if (l > INT_MAX)
380 				errx(EXIT_FAILURE,
381 				    "Too many packets to count: %ld", l);
382 #endif
383 			npackets = l;
384 			break;
385 		case 'd':
386 			options |= F_SO_DEBUG;
387 			break;
388 		case 'f':
389 			if (prog_getuid()) {
390 				errno = EPERM;
391 				errx(1, "Must be superuser to flood ping");
392 			}
393 			options |= F_FLOOD;
394 			setbuf(stdout, NULL);
395 			interval.tv_sec = 0;
396 			interval.tv_nsec = 10 * 1000 * 1000; /* 10 ms */
397 			break;
398 		case 'g':
399 			gateway = optarg;
400 			break;
401 		case 'H':
402 			options |= F_HOSTNAME;
403 			break;
404 		case 'h':		/* hoplimit */
405 			hoplimit = strtol(optarg, &e, 10);
406 			if (*optarg == '\0' || *e != '\0')
407 				errx(1, "illegal hoplimit %s", optarg);
408 			if (255 < hoplimit || hoplimit < -1)
409 				errx(1,
410 				    "illegal hoplimit -- %s", optarg);
411 			break;
412 		case 'I':
413 			ifname = optarg;
414 			options |= F_INTERFACE;
415 #ifndef USE_SIN6_SCOPE_ID
416 			usepktinfo++;
417 #endif
418 			break;
419 		case 'i':		/* wait between sending packets */
420 			intval = strtod(optarg, &e);
421 			if (*optarg == '\0' || *e != '\0')
422 				errx(1, "illegal timing interval %s", optarg);
423 			if (intval < 1 && prog_getuid()) {
424 				errx(1, "%s: only root may use interval < 1s",
425 				    strerror(EPERM));
426 			}
427 			if (intval > INT_MAX/1000.0 - 1.0) {
428 				errx(1, "Interval %s too large", optarg);
429 			}
430 			interval.tv_sec = (time_t)intval;
431 			interval.tv_nsec =
432 			    (long)((intval - interval.tv_sec) * 1000000000);
433 			if (interval.tv_sec < 0 || interval.tv_nsec < 0)
434 				errx(1, "illegal timing interval %s", optarg);
435 			/* less than 1/hz does not make sense */
436 			if (interval.tv_sec == 0 &&
437 			    interval.tv_nsec < 10000000) {
438 				warnx("Interval too small; raised to 0.01");
439 				interval.tv_nsec = 10000000;
440 			}
441 			options |= F_INTERVAL;
442 			break;
443 		case 'l':
444 			if (prog_getuid()) {
445 				errno = EPERM;
446 				errx(1, "Must be superuser to preload");
447 			}
448 			l = strtol(optarg, &e, 10);
449 			if (l < 0 || *optarg == '\0' || *e != '\0')
450 				errx(1, "illegal preload value -- %s", optarg);
451 #if INT_MAX < LONG_MAX
452 			if (l > INT_MAX)
453 				errx(EXIT_FAILURE,
454 				    "Too many preload packets: %ld", l);
455 #endif
456 			preload = l;
457 			break;
458 		case 'm':
459 			mflag++;
460 			break;
461 		case 'n':
462 			options &= ~F_HOSTNAME;
463 			break;
464 		case 'N':
465 			options |= F_NIGROUP;
466 			break;
467 		case 'o':
468 			options |= F_ONCE;
469 			break;
470 		case 'p':		/* fill buffer with user pattern */
471 			options |= F_PINGFILLED;
472 			fill((char *)datap, optarg);
473 				break;
474 		case 'q':
475 			options |= F_QUIET;
476 			break;
477 		case 'S':
478 			memset(&hints, 0, sizeof(struct addrinfo));
479 			hints.ai_flags = AI_NUMERICHOST; /* allow hostname? */
480 			hints.ai_family = AF_INET6;
481 			hints.ai_socktype = SOCK_RAW;
482 			hints.ai_protocol = IPPROTO_ICMPV6;
483 
484 			ret_ga = getaddrinfo(optarg, NULL, &hints, &res);
485 			if (ret_ga) {
486 				errx(1, "invalid source address: %s",
487 				     gai_strerror(ret_ga));
488 			}
489 			/*
490 			 * res->ai_family must be AF_INET6 and res->ai_addrlen
491 			 * must be sizeof(src).
492 			 */
493 			memcpy(&src, res->ai_addr, res->ai_addrlen);
494 			srclen = res->ai_addrlen;
495 			freeaddrinfo(res);
496 			options |= F_SRCADDR;
497 			break;
498 		case 's':		/* size of packet to send */
499 			datalen = strtol(optarg, &e, 10);
500 			if (datalen < 0 || *optarg == '\0' || *e != '\0')
501 				errx(1, "illegal datalen value -- %s", optarg);
502 			if (datalen > MAXDATALEN) {
503 				errx(1,
504 				    "datalen value too large, maximum is %d",
505 				    MAXDATALEN);
506 			}
507 			break;
508 		case 't':
509 			options &= ~F_NOUSERDATA;
510 			options |= F_SUPTYPES;
511 			break;
512 		case 'v':
513 			options |= F_VERBOSE;
514 			break;
515 		case 'w':
516 			options &= ~F_NOUSERDATA;
517 			options |= F_FQDN;
518 			break;
519 		case 'W':
520 			options &= ~F_NOUSERDATA;
521 			options |= F_FQDNOLD;
522 			break;
523 		case 'x':
524 			maxwait = strtod(optarg, &e);
525 			if (*e != '\0' || maxwait <= 0)
526 				errx(EXIT_FAILURE, "Bad/invalid maxwait time: "
527 				    "%s", optarg);
528 			break;
529 		case 'X':
530 			deadline = strtod(optarg, &e);
531 			if (*e != '\0' || deadline <= 0)
532 				errx(EXIT_FAILURE, "Bad/invalid deadline time: "
533 				    "%s", optarg);
534                         break;
535 
536 #if defined(IPSEC) && defined(IPSEC_POLICY_IPSEC)
537 		case 'P':
538 			options |= F_POLICY;
539 			if (!strncmp("in", optarg, 2)) {
540 				if ((policy_in = strdup(optarg)) == NULL)
541 					errx(1, "strdup");
542 			} else if (!strncmp("out", optarg, 3)) {
543 				if ((policy_out = strdup(optarg)) == NULL)
544 					errx(1, "strdup");
545 			} else
546 				errx(1, "invalid security policy");
547 			break;
548 #endif
549 		default:
550 			usage();
551 			/*NOTREACHED*/
552 		}
553 	}
554 
555 	argc -= optind;
556 	argv += optind;
557 
558 	if (argc != 1) {
559 		usage();
560 		/*NOTREACHED*/
561 	}
562 
563 	if (options & F_NIGROUP) {
564 		target = nigroup(argv[argc - 1]);
565 		if (target == NULL) {
566 			usage();
567 			/*NOTREACHED*/
568 		}
569 	} else
570 		target = argv[argc - 1];
571 
572 	/* getaddrinfo */
573 	memset(&hints, 0, sizeof(struct addrinfo));
574 	hints.ai_flags = AI_CANONNAME;
575 	hints.ai_family = AF_INET6;
576 	hints.ai_socktype = SOCK_RAW;
577 	hints.ai_protocol = IPPROTO_ICMPV6;
578 
579 	ret_ga = getaddrinfo(target, NULL, &hints, &res);
580 	if (ret_ga)
581 		errx(1, "%s", gai_strerror(ret_ga));
582 	if (res->ai_canonname)
583 		hostname = res->ai_canonname;
584 	else
585 		hostname = target;
586 
587 	if (!res->ai_addr)
588 		errx(1, "getaddrinfo failed");
589 
590 	memcpy(&dst, res->ai_addr, res->ai_addrlen);
591 
592 	if ((s = prog_socket(res->ai_family, res->ai_socktype,
593 	    res->ai_protocol)) < 0)
594 		err(1, "socket");
595 
596 	/* set the source address if specified. */
597 	if ((options & F_SRCADDR) &&
598 	    prog_bind(s, (struct sockaddr *)&src, srclen) != 0) {
599 		err(1, "bind");
600 	}
601 
602 	/* set the gateway (next hop) if specified */
603 	if (gateway) {
604 		struct addrinfo ghints, *gres;
605 		int error;
606 
607 		memset(&ghints, 0, sizeof(ghints));
608 		ghints.ai_family = AF_INET6;
609 		ghints.ai_socktype = SOCK_RAW;
610 		ghints.ai_protocol = IPPROTO_ICMPV6;
611 
612 		error = getaddrinfo(gateway, NULL, &hints, &gres);
613 		if (error) {
614 			errx(1, "getaddrinfo for the gateway %s: %s",
615 			     gateway, gai_strerror(error));
616 		}
617 		if (gres->ai_next && (options & F_VERBOSE))
618 			warnx("gateway resolves to multiple addresses");
619 
620 		if (prog_setsockopt(s, IPPROTO_IPV6, IPV6_NEXTHOP,
621 			       gres->ai_addr, gres->ai_addrlen)) {
622 			err(1, "setsockopt(IPV6_NEXTHOP)");
623 		}
624 
625 		freeaddrinfo(gres);
626 	}
627 
628 	/*
629 	 * let the kernel pass extension headers of incoming packets,
630 	 * for privileged socket options
631 	 */
632 	if ((options & F_VERBOSE) != 0) {
633 		int opton = 1;
634 
635 		if (prog_setsockopt(s, IPPROTO_IPV6, IPV6_RECVHOPOPTS, &opton,
636 		    sizeof(opton)))
637 			err(1, "setsockopt(IPV6_RECVHOPOPTS)");
638 
639 		if (prog_setsockopt(s, IPPROTO_IPV6, IPV6_RECVDSTOPTS, &opton,
640 		    sizeof(opton)))
641 			err(1, "setsockopt(IPV6_RECVDSTOPTS)");
642 
643 #ifdef IPV6_RECVRTHDRDSTOPTS
644 		if (prog_setsockopt(s, IPPROTO_IPV6, IPV6_RECVRTHDRDSTOPTS, &opton,
645 		    sizeof(opton)))
646 			err(1, "setsockopt(IPV6_RECVRTHDRDSTOPTS)");
647 #endif
648 	}
649 
650 	/* revoke root privilege */
651 	prog_seteuid(prog_getuid());
652 	prog_setuid(prog_getuid());
653 
654 	if ((options & F_FLOOD) && (options & F_INTERVAL))
655 		errx(1, "-f and -i incompatible options");
656 
657 	if ((options & F_NOUSERDATA) == 0) {
658 		if (datalen >= (int)sizeof(struct tv32)) {
659 			/* we can time transfer */
660 			timing = 1;
661 		} else
662 			timing = 0;
663 		/* in F_VERBOSE case, we may get non-echoreply packets*/
664 		if (options & F_VERBOSE)
665 			packlen = 2048 + IP6LEN + ICMP6ECHOLEN + EXTRA;
666 		else
667 			packlen = datalen + IP6LEN + ICMP6ECHOLEN + EXTRA;
668 	} else {
669 		/* suppress timing for node information query */
670 		timing = 0;
671 		datalen = 2048;
672 		packlen = 2048 + IP6LEN + ICMP6ECHOLEN + EXTRA;
673 	}
674 
675 	if (!(packet = (u_char *)malloc(packlen)))
676 		err(1, "Unable to allocate packet");
677 	if (!(options & F_PINGFILLED))
678 		for (i = ICMP6ECHOLEN; i < packlen; ++i)
679 			*datap++ = i;
680 
681 	ident = arc4random() & 0xFFFF;
682 	memset(nonce, 0, sizeof(nonce));
683 	for (i = 0; i < sizeof(nonce); i += sizeof(u_int32_t)) {
684 		uint32_t r = arc4random();
685 		memcpy(&nonce[i], &r, sizeof(r));
686 	}
687 
688 	hold = 1;
689 
690 	if (options & F_SO_DEBUG)
691 		(void)prog_setsockopt(s, SOL_SOCKET, SO_DEBUG, (char *)&hold,
692 		    sizeof(hold));
693 	optval = IPV6_DEFHLIM;
694 	if (IN6_IS_ADDR_MULTICAST(&dst.sin6_addr))
695 		if (prog_setsockopt(s, IPPROTO_IPV6, IPV6_MULTICAST_HOPS,
696 		    &optval, sizeof(optval)) == -1)
697 			err(1, "IPV6_MULTICAST_HOPS");
698 
699 	if (mflag != 1) {
700 		optval = mflag > 1 ? 0 : 1;
701 
702 		if (prog_setsockopt(s, IPPROTO_IPV6, IPV6_USE_MIN_MTU,
703 		    &optval, sizeof(optval)) == -1)
704 			err(1, "setsockopt(IPV6_USE_MIN_MTU)");
705 	} else {
706 		optval = 1;
707 		if (prog_setsockopt(s, IPPROTO_IPV6, IPV6_RECVPATHMTU,
708 		    &optval, sizeof(optval)) == -1)
709 			err(1, "setsockopt(IPV6_RECVPATHMTU)");
710 	}
711 
712 #if defined(IPSEC) && defined(IPSEC_POLICY_IPSEC)
713 	if (options & F_POLICY) {
714 		if (setpolicy(s, policy_in) < 0)
715 			errx(1, "%s", ipsec_strerror());
716 		if (setpolicy(s, policy_out) < 0)
717 			errx(1, "%s", ipsec_strerror());
718 	}
719 #endif
720 
721 #ifdef ICMP6_FILTER
722     {
723 	struct icmp6_filter filt;
724 	if (!(options & F_VERBOSE)) {
725 		ICMP6_FILTER_SETBLOCKALL(&filt);
726 		if ((options & F_FQDN) || (options & F_FQDNOLD) ||
727 		    (options & F_NODEADDR) || (options & F_SUPTYPES))
728 			ICMP6_FILTER_SETPASS(ICMP6_NI_REPLY, &filt);
729 		else
730 			ICMP6_FILTER_SETPASS(ICMP6_ECHO_REPLY, &filt);
731 	} else {
732 		ICMP6_FILTER_SETPASSALL(&filt);
733 	}
734 	if (prog_setsockopt(s, IPPROTO_ICMPV6, ICMP6_FILTER, &filt,
735 	    sizeof(filt)) < 0)
736 		err(1, "setsockopt(ICMP6_FILTER)");
737     }
738 #endif /*ICMP6_FILTER*/
739 
740 	/* let the kernel pass extension headers of incoming packets */
741 	if ((options & F_VERBOSE) != 0) {
742 		int opton = 1;
743 
744 		if (prog_setsockopt(s, IPPROTO_IPV6, IPV6_RECVRTHDR, &opton,
745 		    sizeof(opton)))
746 			err(1, "setsockopt(IPV6_RECVRTHDR)");
747 	}
748 
749 /*
750 	optval = 1;
751 	if (IN6_IS_ADDR_MULTICAST(&dst.sin6_addr))
752 		if (prog_setsockopt(s, IPPROTO_IPV6, IPV6_MULTICAST_LOOP,
753 		    &optval, sizeof(optval)) == -1)
754 			err(1, "IPV6_MULTICAST_LOOP");
755 */
756 
757 	/* Specify the outgoing interface and/or the source address */
758 	if (usepktinfo)
759 		ip6optlen += CMSG_SPACE(sizeof(struct in6_pktinfo));
760 
761 	if (hoplimit != -1)
762 		ip6optlen += CMSG_SPACE(sizeof(int));
763 
764 	/* set IP6 packet options */
765 	if (ip6optlen) {
766 		if ((scmsg = (char *)malloc(ip6optlen)) == 0)
767 			errx(1, "can't allocate enough memory");
768 		smsghdr.msg_control = (caddr_t)scmsg;
769 		smsghdr.msg_controllen = ip6optlen;
770 		scmsgp = (struct cmsghdr *)scmsg;
771 	}
772 	if (usepktinfo) {
773 		pktinfo = (struct in6_pktinfo *)(CMSG_DATA(scmsgp));
774 		memset(pktinfo, 0, sizeof(*pktinfo));
775 		scmsgp->cmsg_len = CMSG_LEN(sizeof(struct in6_pktinfo));
776 		scmsgp->cmsg_level = IPPROTO_IPV6;
777 		scmsgp->cmsg_type = IPV6_PKTINFO;
778 		scmsgp = CMSG_NXTHDR(&smsghdr, scmsgp);
779 	}
780 
781 	/* set the outgoing interface */
782 	if (ifname) {
783 #ifndef USE_SIN6_SCOPE_ID
784 		/* pktinfo must have already been allocated */
785 		if ((pktinfo->ipi6_ifindex = if_nametoindex(ifname)) == 0)
786 			errx(1, "%s: invalid interface name", ifname);
787 #else
788 		if ((dst.sin6_scope_id = if_nametoindex(ifname)) == 0)
789 			errx(1, "%s: invalid interface name", ifname);
790 #endif
791 	}
792 	if (hoplimit != -1) {
793 		scmsgp->cmsg_len = CMSG_LEN(sizeof(int));
794 		scmsgp->cmsg_level = IPPROTO_IPV6;
795 		scmsgp->cmsg_type = IPV6_HOPLIMIT;
796 		*(int *)(CMSG_DATA(scmsgp)) = hoplimit;
797 
798 		scmsgp = CMSG_NXTHDR(&smsghdr, scmsgp);
799 	}
800 
801 	if (!(options & F_SRCADDR)) {
802 		/*
803 		 * get the source address. XXX since we revoked the root
804 		 * privilege, we cannot use a raw socket for this.
805 		 */
806 		int dummy;
807 		socklen_t len = sizeof(src);
808 
809 		if ((dummy = prog_socket(AF_INET6, SOCK_DGRAM, 0)) < 0)
810 			err(1, "UDP socket");
811 
812 		src.sin6_family = AF_INET6;
813 		src.sin6_addr = dst.sin6_addr;
814 		src.sin6_port = ntohs(DUMMY_PORT);
815 		src.sin6_scope_id = dst.sin6_scope_id;
816 
817 		if (pktinfo &&
818 		    prog_setsockopt(dummy, IPPROTO_IPV6, IPV6_PKTINFO,
819 		    (void *)pktinfo, sizeof(*pktinfo)))
820 			err(1, "UDP setsockopt(IPV6_PKTINFO)");
821 
822 		if (hoplimit != -1 &&
823 		    prog_setsockopt(dummy, IPPROTO_IPV6, IPV6_UNICAST_HOPS,
824 		    (void *)&hoplimit, sizeof(hoplimit)))
825 			err(1, "UDP setsockopt(IPV6_UNICAST_HOPS)");
826 
827 		if (hoplimit != -1 &&
828 		    prog_setsockopt(dummy, IPPROTO_IPV6, IPV6_MULTICAST_HOPS,
829 		    (void *)&hoplimit, sizeof(hoplimit)))
830 			err(1, "UDP setsockopt(IPV6_MULTICAST_HOPS)");
831 
832 		if (rthdr &&
833 		    prog_setsockopt(dummy, IPPROTO_IPV6, IPV6_RTHDR,
834 		    (void *)rthdr, (rthdr->ip6r_len + 1) << 3))
835 			err(1, "UDP setsockopt(IPV6_RTHDR)");
836 
837 		if (prog_connect(dummy, (struct sockaddr *)&src, len) < 0)
838 			err(1, "UDP connect");
839 
840 		if (prog_getsockname(dummy, (struct sockaddr *)&src, &len) < 0)
841 			err(1, "getsockname");
842 
843 		prog_close(dummy);
844 	}
845 
846 	if (sockbufsize) {
847 		if (datalen > sockbufsize)
848 			warnx("you need -b to increase socket buffer size");
849 		if (prog_setsockopt(s, SOL_SOCKET, SO_SNDBUF, &sockbufsize,
850 		    sizeof(sockbufsize)) < 0)
851 			err(1, "setsockopt(SO_SNDBUF)");
852 		if (prog_setsockopt(s, SOL_SOCKET, SO_RCVBUF, &sockbufsize,
853 		    sizeof(sockbufsize)) < 0)
854 			err(1, "setsockopt(SO_RCVBUF)");
855 	} else {
856 		if (datalen > 8 * 1024)	/*XXX*/
857 			warnx("you need -b to increase socket buffer size");
858 		/*
859 		 * When pinging the broadcast address, you can get a lot of
860 		 * answers. Doing something so evil is useful if you are trying
861 		 * to stress the ethernet, or just want to fill the arp cache
862 		 * to get some stuff for /etc/ethers.
863 		 */
864 		hold = 48 * 1024;
865 		prog_setsockopt(s, SOL_SOCKET, SO_RCVBUF, (char *)&hold,
866 		    sizeof(hold));
867 	}
868 
869 	optval = 1;
870 #ifndef USE_SIN6_SCOPE_ID
871 	if (prog_setsockopt(s, IPPROTO_IPV6, IPV6_RECVPKTINFO, &optval,
872 	    sizeof(optval)) < 0)
873 		warn("setsockopt(IPV6_RECVPKTINFO)"); /* XXX err? */
874 #endif
875 
876 	if (prog_setsockopt(s, IPPROTO_IPV6, IPV6_RECVHOPLIMIT, &optval,
877 	    sizeof(optval)) < 0)
878 		warn("setsockopt(IPV6_RECVHOPLIMIT)"); /* XXX err? */
879 
880 	printf("PING6(%lu=40+8+%lu bytes) ", (unsigned long)(40 + pingerlen()),
881 	    (unsigned long)(pingerlen() - 8));
882 	printf("%s --> ", pr_addr((struct sockaddr *)&src, sizeof(src)));
883 	printf("%s\n", pr_addr((struct sockaddr *)&dst, sizeof(dst)));
884 
885 	while (preload--)		/* Fire off them quickies. */
886 		pinger();
887 
888 	(void)signal(SIGINT, onsignal);
889 #ifdef SIGINFO
890 	(void)signal(SIGINFO, onsignal);
891 #endif
892 
893 	seenint = 0;
894 #ifdef SIGINFO
895 	seeninfo = 0;
896 #endif
897 
898 	doit(packet, packlen);
899 	/*NOTREACHED*/
900 	return 0;
901 }
902 
903 static void
904 doit(u_char *packet, u_int packlen)
905 {
906 	int cc;
907 	struct pollfd fdmaskp[1];
908 	struct sockaddr_in6 from;
909 	double sec, last, d_last;
910 	long orig_npackets = npackets;
911 
912 	if (npackets == 0)
913 		npackets = LONG_MAX;
914 
915 	clock_gettime(CLOCK_MONOTONIC, &now);
916 	if (deadline > 0) {
917 		last = timespec_to_sec(&now) + deadline;
918 		d_last = 0;
919 	} else {
920 		last = 0;
921 		d_last = 365*24*60*60;
922 	}
923 
924 	for (;;) {
925 		struct msghdr m;
926 		u_char buf[1024];
927 		struct iovec iov[2];
928 
929 		clock_gettime(CLOCK_MONOTONIC, &now);
930 
931 		if (seenint) {
932 			onsigexit(SIGINT);
933 			seenint = 0;
934 			continue;
935 		}
936 #ifdef SIGINFO
937 		if (seeninfo) {
938 			summary();
939 			seeninfo = 0;
940 			continue;
941 		}
942 #endif
943 		if (last != 0)
944 			d_last = last - timespec_to_sec(&now);
945 
946 		if (ntransmitted < npackets && d_last > 0) {
947 			/* send if within 100 usec or late for next packet */
948 			sec = diffsec(&next_tx, &now);
949 			if ((sec <= 0.0001 && (options & F_FLOOD) == 0) ||
950 			    (lastrcvd && (options & F_FLOOD))) {
951 				pinger();
952 				sec = diffsec(&next_tx, &now);
953 			}
954 			if (sec < 0.0)
955 				sec = 0.0;
956 			if (d_last < sec)
957 				sec = d_last;
958 		} else {
959 			/* For the last response, wait twice as long as the
960 			 * worst case seen, or 10 times as long as the
961 			 * maximum interpacket interval, whichever is longer.
962 			 */
963 			sec = MAX(2 * tmax, 10 * interval.tv_sec) -
964 			    diffsec(&now, &last_tx);
965 			if (d_last < sec)
966 				sec = d_last;
967 			if (sec <= 0)
968 				break;
969 		}
970 
971 		fdmaskp[0].fd = s;
972 		fdmaskp[0].events = POLLIN;
973 		cc = prog_poll(fdmaskp, 1, (int)(sec * 1000));
974 		if (cc < 0) {
975 			if (errno != EINTR) {
976 				warn("poll");
977 				sleep(1);
978 			}
979 			continue;
980 		} else if (cc == 0)
981 			continue;
982 
983 		m.msg_name = (caddr_t)&from;
984 		m.msg_namelen = sizeof(from);
985 		memset(&iov, 0, sizeof(iov));
986 		iov[0].iov_base = (caddr_t)packet;
987 		iov[0].iov_len = packlen;
988 		m.msg_iov = iov;
989 		m.msg_iovlen = 1;
990 		m.msg_control = (caddr_t)buf;
991 		m.msg_controllen = sizeof(buf);
992 
993 		cc = prog_recvmsg(s, &m, 0);
994 		if (cc < 0) {
995 			if (errno != EINTR) {
996 				warn("recvmsg");
997 				sleep(1);
998 			}
999 			continue;
1000 		} else if (cc == 0) {
1001 			int mtu;
1002 
1003 			/*
1004 			 * receive control messages only. Process the
1005 			 * exceptions (currently the only possiblity is
1006 			 * a path MTU notification.)
1007 			 */
1008 			if ((mtu = get_pathmtu(&m)) > 0) {
1009 				if ((options & F_VERBOSE) != 0) {
1010 					printf("new path MTU (%d) is "
1011 					    "notified\n", mtu);
1012 				}
1013 			}
1014 			continue;
1015 		} else {
1016 			/*
1017 			 * an ICMPv6 message (probably an echoreply) arrived.
1018 			 */
1019 			pr_pack(packet, cc, &m);
1020 		}
1021 		if (npackets && nreceived >= npackets)
1022 			break;
1023 		if (nreceived != 0 && (options & F_ONCE))
1024 			break;
1025 	}
1026 
1027 	summary();
1028 
1029 	if (orig_npackets)
1030 		exit(nreceived != orig_npackets);
1031 	else
1032 		exit(nreceived == 0);
1033 }
1034 
1035 static void
1036 onsignal(int sig)
1037 {
1038 
1039 	switch (sig) {
1040 	case SIGINT:
1041 		seenint++;
1042 		break;
1043 #ifdef SIGINFO
1044 	case SIGINFO:
1045 		seeninfo++;
1046 		break;
1047 #endif
1048 	}
1049 }
1050 
1051 /*
1052  * pinger --
1053  *	Compose and transmit an ICMP ECHO REQUEST packet.  The IP packet
1054  * will be added on by the kernel.  The ID field is our UNIX process ID,
1055  * and the sequence number is an ascending integer.  The first 8 bytes
1056  * of the data portion are used to hold a UNIX "timeval" struct in VAX
1057  * byte-order, to compute the round-trip time.
1058  */
1059 static size_t
1060 pingerlen(void)
1061 {
1062 	size_t l;
1063 
1064 	if (options & F_FQDN)
1065 		l = ICMP6_NIQLEN + sizeof(dst.sin6_addr);
1066 	else if (options & F_FQDNOLD)
1067 		l = ICMP6_NIQLEN;
1068 	else if (options & F_NODEADDR)
1069 		l = ICMP6_NIQLEN + sizeof(dst.sin6_addr);
1070 	else if (options & F_SUPTYPES)
1071 		l = ICMP6_NIQLEN;
1072 	else
1073 		l = ICMP6ECHOLEN + datalen;
1074 
1075 	return l;
1076 }
1077 
1078 static void
1079 pinger(void)
1080 {
1081 	struct icmp6_hdr *icp;
1082 	struct iovec iov[2];
1083 	int i, cc;
1084 	struct icmp6_nodeinfo *nip;
1085 	uint16_t seq;
1086 
1087 	if (npackets && ntransmitted >= npackets)
1088 		return;	/* no more transmission */
1089 
1090 	icp = (struct icmp6_hdr *)outpack;
1091 	nip = (struct icmp6_nodeinfo *)outpack;
1092 	memset(icp, 0, sizeof(*icp));
1093 	icp->icmp6_cksum = 0;
1094 	seq = ntransmitted++;
1095 	lastrcvd = 0;
1096 	CLR(seq % mx_dup_ck);
1097 	seq = ntohs(seq);
1098 
1099 	if (options & F_FQDN) {
1100 		icp->icmp6_code = ICMP6_NI_SUBJ_IPV6;
1101 		nip->ni_qtype = htons(NI_QTYPE_FQDN);
1102 		nip->ni_flags = htons(0);
1103 
1104 		memcpy(&outpack[ICMP6_NIQLEN], &dst.sin6_addr,
1105 		    sizeof(dst.sin6_addr));
1106 		cc = ICMP6_NIQLEN + sizeof(dst.sin6_addr);
1107 	} else if (options & F_FQDNOLD) {
1108 		/* packet format in 03 draft - no Subject data on queries */
1109 		icp->icmp6_code = 0;	/* code field is always 0 */
1110 		nip->ni_qtype = htons(NI_QTYPE_FQDN);
1111 		nip->ni_flags = htons(0);
1112 
1113 		cc = ICMP6_NIQLEN;
1114 	} else if (options & F_NODEADDR) {
1115 		icp->icmp6_code = ICMP6_NI_SUBJ_IPV6;
1116 		nip->ni_qtype = htons(NI_QTYPE_NODEADDR);
1117 		nip->ni_flags = naflags;
1118 
1119 		memcpy(&outpack[ICMP6_NIQLEN], &dst.sin6_addr,
1120 		    sizeof(dst.sin6_addr));
1121 		cc = ICMP6_NIQLEN + sizeof(dst.sin6_addr);
1122 	} else if (options & F_SUPTYPES) {
1123 		icp->icmp6_code = ICMP6_NI_SUBJ_FQDN;	/*empty*/
1124 		nip->ni_qtype = htons(NI_QTYPE_SUPTYPES);
1125 		/* we support compressed bitmap */
1126 		nip->ni_flags = NI_SUPTYPE_FLAG_COMPRESS;
1127 
1128 		cc = ICMP6_NIQLEN;
1129 	} else
1130 		cc = 0;	/* XXX: gcc */
1131 
1132 	if (options & (F_FQDN|F_FQDNOLD|F_NODEADDR|F_SUPTYPES)) {
1133 		icp->icmp6_type = ICMP6_NI_QUERY;
1134 		memcpy(nip->icmp6_ni_nonce, nonce,
1135 		    sizeof(nip->icmp6_ni_nonce));
1136 		memcpy(nip->icmp6_ni_nonce, &seq, sizeof(seq));
1137 		datalen = 0;
1138 	} else {
1139 		icp->icmp6_type = ICMP6_ECHO_REQUEST;
1140 		icp->icmp6_code = 0;
1141 		icp->icmp6_id = htons(ident);
1142 		icp->icmp6_seq = seq;
1143 		if (timing) {
1144 			struct timeval tv;
1145 			struct tv32 *tv32;
1146 			(void)gettimeofday(&tv, NULL);
1147 			tv32 = (struct tv32 *)&outpack[ICMP6ECHOLEN];
1148 			tv32->tv32_sec = htonl(tv.tv_sec);
1149 			tv32->tv32_usec = htonl(tv.tv_usec);
1150 		}
1151 		cc = ICMP6ECHOLEN + datalen;
1152 	}
1153 
1154 #ifdef DIAGNOSTIC
1155 	if (pingerlen() != cc)
1156 		errx(1, "internal error; length mismatch");
1157 #endif
1158 
1159 	smsghdr.msg_name = (caddr_t)&dst;
1160 	smsghdr.msg_namelen = sizeof(dst);
1161 	memset(&iov, 0, sizeof(iov));
1162 	iov[0].iov_base = (caddr_t)outpack;
1163 	iov[0].iov_len = cc;
1164 	smsghdr.msg_iov = iov;
1165 	smsghdr.msg_iovlen = 1;
1166 
1167 	i = prog_sendmsg(s, &smsghdr, 0);
1168 
1169 	if (i < 0 || i != cc)  {
1170 		if (i < 0)
1171 			warn("sendmsg");
1172 		printf("ping6: wrote %s %d chars, ret=%d\n",
1173 		    hostname, cc, i);
1174 	}
1175 	if (!(options & F_QUIET) && options & F_FLOOD)
1176 		(void)write(STDOUT_FILENO, &DOT, 1);
1177 
1178 	last_tx = now;
1179 	if (next_tx.tv_sec == 0) {
1180 		first_tx = now;
1181 		next_tx = now;
1182 	}
1183 
1184 	/* Transmit regularly, at always the same microsecond in the
1185 	 * second when going at one packet per second.
1186 	 * If we are at most 100 ms behind, send extras to get caught up.
1187 	 * Otherwise, skip packets we were too slow to send.
1188 	 */
1189 	if (diffsec(&next_tx, &now) <= interval.tv_sec) {
1190 		do {
1191 			timespecadd(&next_tx, &interval, &next_tx);
1192 		} while (diffsec(&next_tx, &now) < -0.1);
1193 	}
1194 }
1195 
1196 static int
1197 myechoreply(const struct icmp6_hdr *icp)
1198 {
1199 	if (ntohs(icp->icmp6_id) == ident)
1200 		return 1;
1201 	else
1202 		return 0;
1203 }
1204 
1205 static int
1206 mynireply(const struct icmp6_nodeinfo *nip)
1207 {
1208 	if (memcmp(nip->icmp6_ni_nonce + sizeof(u_int16_t),
1209 	    nonce + sizeof(u_int16_t),
1210 	    sizeof(nonce) - sizeof(u_int16_t)) == 0)
1211 		return 1;
1212 	else
1213 		return 0;
1214 }
1215 
1216 static char *
1217 dnsdecode(const u_char **sp, const u_char *ep, const u_char *base, char *buf,
1218 	  size_t bufsiz)
1219 {
1220 	int i;
1221 	const u_char *cp;
1222 	char cresult[MAXDNAME + 1];
1223 	const u_char *comp;
1224 	int l;
1225 
1226 	i = 0;		/* XXXGCC -Wuninitialized [sun2] */
1227 
1228 	cp = *sp;
1229 	*buf = '\0';
1230 
1231 	if (cp >= ep)
1232 		return NULL;
1233 	while (cp < ep) {
1234 		i = *cp;
1235 		if (i == 0 || cp != *sp) {
1236 			if (strlcat((char *)buf, ".", bufsiz) >= bufsiz)
1237 				return NULL;	/*result overrun*/
1238 		}
1239 		if (i == 0)
1240 			break;
1241 		cp++;
1242 
1243 		if ((i & 0xc0) == 0xc0 && cp - base > (i & 0x3f)) {
1244 			/* DNS compression */
1245 			if (!base)
1246 				return NULL;
1247 
1248 			comp = base + (i & 0x3f);
1249 			if (dnsdecode(&comp, cp, base, cresult,
1250 			    sizeof(cresult)) == NULL)
1251 				return NULL;
1252 			if (strlcat(buf, cresult, bufsiz) >= bufsiz)
1253 				return NULL;	/*result overrun*/
1254 			break;
1255 		} else if ((i & 0x3f) == i) {
1256 			if (i > ep - cp)
1257 				return NULL;	/*source overrun*/
1258 			while (i-- > 0 && cp < ep) {
1259 				l = snprintf(cresult, sizeof(cresult),
1260 				    isprint(*cp) ? "%c" : "\\%03o", *cp & 0xff);
1261 				if (l >= (int)sizeof(cresult) || l < 0)
1262 					return NULL;
1263 				if (strlcat(buf, cresult, bufsiz) >= bufsiz)
1264 					return NULL;	/*result overrun*/
1265 				cp++;
1266 			}
1267 		} else
1268 			return NULL;	/*invalid label*/
1269 	}
1270 	if (i != 0)
1271 		return NULL;	/*not terminated*/
1272 	cp++;
1273 	*sp = cp;
1274 	return buf;
1275 }
1276 
1277 /*
1278  * pr_pack --
1279  *	Print out the packet, if it came from us.  This logic is necessary
1280  * because ALL readers of the ICMP socket get a copy of ALL ICMP packets
1281  * which arrive ('tis only fair).  This permits multiple copies of this
1282  * program to be run without having intermingled output (or statistics!).
1283  */
1284 static void
1285 pr_pack(u_char *buf, int cc, struct msghdr *mhdr)
1286 {
1287 #define safeputc(c)	printf((isprint((c)) ? "%c" : "\\%03o"), c)
1288 	struct icmp6_hdr *icp;
1289 	struct icmp6_nodeinfo *ni;
1290 	int i;
1291 	int hoplim;
1292 	struct sockaddr *from;
1293 	int fromlen;
1294 	u_char *cp = NULL, *dp, *end = buf + cc;
1295 	struct in6_pktinfo *pktinfo = NULL;
1296 	struct timeval tv, tp;
1297 	struct tv32 *tpp;
1298 	double triptime = 0;
1299 	int dupflag;
1300 	size_t off;
1301 	int oldfqdn;
1302 	u_int16_t seq;
1303 	char dnsname[MAXDNAME + 1];
1304 
1305 	(void)gettimeofday(&tv, NULL);
1306 
1307 	if (!mhdr || !mhdr->msg_name ||
1308 	    mhdr->msg_namelen != sizeof(struct sockaddr_in6) ||
1309 	    ((struct sockaddr *)mhdr->msg_name)->sa_family != AF_INET6) {
1310 		if (options & F_VERBOSE)
1311 			warnx("invalid peername");
1312 		return;
1313 	}
1314 	from = (struct sockaddr *)mhdr->msg_name;
1315 	fromlen = mhdr->msg_namelen;
1316 	if (cc < (int)sizeof(struct icmp6_hdr)) {
1317 		if (options & F_VERBOSE)
1318 			warnx("packet too short (%d bytes) from %s", cc,
1319 			    pr_addr(from, fromlen));
1320 		return;
1321 	}
1322 	icp = (struct icmp6_hdr *)buf;
1323 	ni = (struct icmp6_nodeinfo *)buf;
1324 	off = 0;
1325 
1326 	if ((hoplim = get_hoplim(mhdr)) == -1) {
1327 		warnx("failed to get receiving hop limit");
1328 		return;
1329 	}
1330 	if ((pktinfo = get_rcvpktinfo(mhdr)) == NULL) {
1331 		warnx("failed to get receiving packet information");
1332 		return;
1333 	}
1334 
1335 	if (icp->icmp6_type == ICMP6_ECHO_REPLY && myechoreply(icp)) {
1336 		seq = ntohs(icp->icmp6_seq);
1337 		++nreceived;
1338 		lastrcvd = 1;
1339 		if (timing) {
1340 			tpp = (struct tv32 *)(icp + 1);
1341 			tp.tv_sec = ntohl(tpp->tv32_sec);
1342 			tp.tv_usec = ntohl(tpp->tv32_usec);
1343 			tvsub(&tv, &tp);
1344 			triptime = ((double)tv.tv_sec) * 1000.0 +
1345 			    ((double)tv.tv_usec) / 1000.0;
1346 			if (maxwait > 0 && triptime > maxwait) {
1347 				nreceived--;
1348 				return;	/* DISCARD */
1349 			}
1350 			tsum += triptime;
1351 			tsumsq += triptime * triptime;
1352 			if (triptime < tmin)
1353 				tmin = triptime;
1354 			if (triptime > tmax)
1355 				tmax = triptime;
1356 		}
1357 
1358 		if (TST(seq % mx_dup_ck)) {
1359 			++nrepeats;
1360 			--nreceived;
1361 			dupflag = 1;
1362 		} else {
1363 			SET(seq % mx_dup_ck);
1364 			dupflag = 0;
1365 		}
1366 
1367 		if (options & F_QUIET)
1368 			return;
1369 
1370 		if (options & F_FLOOD)
1371 			(void)write(STDOUT_FILENO, &BSPACE, 1);
1372 		else {
1373 			printf("%d bytes from %s, icmp_seq=%u", cc,
1374 			    pr_addr(from, fromlen), seq);
1375 			printf(" hlim=%d", hoplim);
1376 			if ((options & F_VERBOSE) != 0) {
1377 				struct sockaddr_in6 dstsa;
1378 
1379 				memset(&dstsa, 0, sizeof(dstsa));
1380 				dstsa.sin6_family = AF_INET6;
1381 #ifdef SIN6_LEN
1382 				dstsa.sin6_len = sizeof(dstsa);
1383 #endif
1384 				dstsa.sin6_scope_id = pktinfo->ipi6_ifindex;
1385 				dstsa.sin6_addr = pktinfo->ipi6_addr;
1386 				printf(" dst=%s",
1387 				    pr_addr((struct sockaddr *)&dstsa,
1388 				    sizeof(dstsa)));
1389 			}
1390 			if (timing)
1391 				printf(" time=%.3f ms", triptime);
1392 			if (dupflag)
1393 				printf("(DUP!)");
1394 			/* check the data */
1395 			cp = buf + off + ICMP6ECHOLEN + ICMP6ECHOTMLEN;
1396 			dp = outpack + ICMP6ECHOLEN + ICMP6ECHOTMLEN;
1397 			for (i = 8; cp < end; ++i, ++cp, ++dp) {
1398 				if (*cp != *dp) {
1399 					printf("\nwrong data byte #%d should be 0x%x but was 0x%x", i, *dp, *cp);
1400 					break;
1401 				}
1402 			}
1403 		}
1404 	} else if (icp->icmp6_type == ICMP6_NI_REPLY && mynireply(ni)) {
1405 		memcpy(&seq, ni->icmp6_ni_nonce, sizeof(seq));
1406 		seq = ntohs(seq);
1407 		++nreceived;
1408 		if (TST(seq % mx_dup_ck)) {
1409 			++nrepeats;
1410 			--nreceived;
1411 			dupflag = 1;
1412 		} else {
1413 			SET(seq % mx_dup_ck);
1414 			dupflag = 0;
1415 		}
1416 
1417 		if (options & F_QUIET)
1418 			return;
1419 
1420 		printf("%d bytes from %s: ", cc, pr_addr(from, fromlen));
1421 
1422 		switch (ntohs(ni->ni_code)) {
1423 		case ICMP6_NI_SUCCESS:
1424 			break;
1425 		case ICMP6_NI_REFUSED:
1426 			printf("refused, type 0x%x", ntohs(ni->ni_type));
1427 			goto fqdnend;
1428 		case ICMP6_NI_UNKNOWN:
1429 			printf("unknown, type 0x%x", ntohs(ni->ni_type));
1430 			goto fqdnend;
1431 		default:
1432 			printf("unknown code 0x%x, type 0x%x",
1433 			    ntohs(ni->ni_code), ntohs(ni->ni_type));
1434 			goto fqdnend;
1435 		}
1436 
1437 		switch (ntohs(ni->ni_qtype)) {
1438 		case NI_QTYPE_NOOP:
1439 			printf("NodeInfo NOOP");
1440 			break;
1441 		case NI_QTYPE_SUPTYPES:
1442 			pr_suptypes(ni, end - (u_char *)ni);
1443 			break;
1444 		case NI_QTYPE_NODEADDR:
1445 			pr_nodeaddr(ni, end - (u_char *)ni);
1446 			break;
1447 		case NI_QTYPE_FQDN:
1448 		default:	/* XXX: for backward compatibility */
1449 			cp = (u_char *)ni + ICMP6_NIRLEN;
1450 			if (buf[off + ICMP6_NIRLEN] ==
1451 			    cc - off - ICMP6_NIRLEN - 1)
1452 				oldfqdn = 1;
1453 			else
1454 				oldfqdn = 0;
1455 			if (oldfqdn) {
1456 				cp++;	/* skip length */
1457 				while (cp < end) {
1458 					safeputc(*cp & 0xff);
1459 					cp++;
1460 				}
1461 			} else {
1462 				i = 0;
1463 				while (cp < end) {
1464 					if (dnsdecode((void *)&cp, end,
1465 					    (const u_char *)(ni + 1), dnsname,
1466 					    sizeof(dnsname)) == NULL) {
1467 						printf("???");
1468 						break;
1469 					}
1470 					/*
1471 					 * name-lookup special handling for
1472 					 * truncated name
1473 					 */
1474 					if (cp + 1 <= end && !*cp &&
1475 					    strlen(dnsname) > 0) {
1476 						dnsname[strlen(dnsname) - 1] = '\0';
1477 						cp++;
1478 					}
1479 					printf("%s%s", i > 0 ? "," : "",
1480 					    dnsname);
1481 				}
1482 			}
1483 			if (options & F_VERBOSE) {
1484 				int32_t ttl;
1485 				int comma = 0;
1486 
1487 				printf(" (");	/*)*/
1488 
1489 				switch (ni->ni_code) {
1490 				case ICMP6_NI_REFUSED:
1491 					printf("refused");
1492 					comma++;
1493 					break;
1494 				case ICMP6_NI_UNKNOWN:
1495 					printf("unknown qtype");
1496 					comma++;
1497 					break;
1498 				}
1499 
1500 				if ((end - (u_char *)ni) < ICMP6_NIRLEN) {
1501 					/* case of refusion, unknown */
1502 					/*(*/
1503 					putchar(')');
1504 					goto fqdnend;
1505 				}
1506 				ttl = (int32_t)ntohl(*(u_long *)&buf[off+ICMP6ECHOLEN+8]);
1507 				if (comma)
1508 					printf(",");
1509 				if (!(ni->ni_flags & NI_FQDN_FLAG_VALIDTTL)) {
1510 					printf("TTL=%d:meaningless",
1511 					    (int)ttl);
1512 				} else {
1513 					if (ttl < 0) {
1514 						printf("TTL=%d:invalid",
1515 						   ttl);
1516 					} else
1517 						printf("TTL=%d", ttl);
1518 				}
1519 				comma++;
1520 
1521 				if (oldfqdn) {
1522 					if (comma)
1523 						printf(",");
1524 					printf("03 draft");
1525 					comma++;
1526 				} else {
1527 					cp = (u_char *)ni + ICMP6_NIRLEN;
1528 					if (cp == end) {
1529 						if (comma)
1530 							printf(",");
1531 						printf("no name");
1532 						comma++;
1533 					}
1534 				}
1535 
1536 				if (buf[off + ICMP6_NIRLEN] !=
1537 				    cc - off - ICMP6_NIRLEN - 1 && oldfqdn) {
1538 					if (comma)
1539 						printf(",");
1540 					printf("invalid namelen:%d/%lu",
1541 					    buf[off + ICMP6_NIRLEN],
1542 					    (u_long)cc - off - ICMP6_NIRLEN - 1);
1543 					comma++;
1544 				}
1545 				/*(*/
1546 				putchar(')');
1547 			}
1548 		fqdnend:
1549 			;
1550 		}
1551 	} else {
1552 		/* We've got something other than an ECHOREPLY */
1553 		if (!(options & F_VERBOSE))
1554 			return;
1555 		printf("%d bytes from %s: ", cc, pr_addr(from, fromlen));
1556 		pr_icmph(icp, end);
1557 	}
1558 
1559 	if (!(options & F_FLOOD)) {
1560 		(void)putchar('\n');
1561 		if (options & F_VERBOSE)
1562 			pr_exthdrs(mhdr);
1563 		(void)fflush(stdout);
1564 	}
1565 #undef safeputc
1566 }
1567 
1568 static void
1569 pr_exthdrs(struct msghdr *mhdr)
1570 {
1571 	struct cmsghdr *cm;
1572 
1573 	for (cm = (struct cmsghdr *)CMSG_FIRSTHDR(mhdr); cm;
1574 	     cm = (struct cmsghdr *)CMSG_NXTHDR(mhdr, cm)) {
1575 		if (cm->cmsg_level != IPPROTO_IPV6)
1576 			continue;
1577 
1578 		switch (cm->cmsg_type) {
1579 		case IPV6_HOPOPTS:
1580 			printf("  HbH Options: ");
1581 			pr_ip6opt(CMSG_DATA(cm));
1582 			break;
1583 		case IPV6_DSTOPTS:
1584 #ifdef IPV6_RTHDRDSTOPTS
1585 		case IPV6_RTHDRDSTOPTS:
1586 #endif
1587 			printf("  Dst Options: ");
1588 			pr_ip6opt(CMSG_DATA(cm));
1589 			break;
1590 		case IPV6_RTHDR:
1591 			printf("  Routing: ");
1592 			pr_rthdr(CMSG_DATA(cm));
1593 			break;
1594 		}
1595 	}
1596 }
1597 
1598 static void
1599 pr_ip6opt(void *extbuf)
1600 {
1601 	struct ip6_hbh *ext;
1602 	int currentlen;
1603 	u_int8_t type;
1604 	size_t extlen;
1605 	socklen_t len;
1606 	void *databuf;
1607 	size_t offset;
1608 	u_int16_t value2;
1609 	u_int32_t value4;
1610 
1611 	ext = (struct ip6_hbh *)extbuf;
1612 	extlen = (ext->ip6h_len + 1) * 8;
1613 	printf("nxt %u, len %u (%lu bytes)\n", ext->ip6h_nxt,
1614 	    (unsigned int)ext->ip6h_len, (unsigned long)extlen);
1615 
1616 	currentlen = 0;
1617 	while (1) {
1618 		currentlen = inet6_opt_next(extbuf, extlen, currentlen,
1619 		    &type, &len, &databuf);
1620 		if (currentlen == -1)
1621 			break;
1622 		switch (type) {
1623 		/*
1624 		 * Note that inet6_opt_next automatically skips any padding
1625 		 * optins.
1626 		 */
1627 		case IP6OPT_JUMBO:
1628 			offset = 0;
1629 			offset = inet6_opt_get_val(databuf, offset,
1630 			    &value4, sizeof(value4));
1631 			printf("    Jumbo Payload Opt: Length %u\n",
1632 			    (u_int32_t)ntohl(value4));
1633 			break;
1634 		case IP6OPT_ROUTER_ALERT:
1635 			offset = 0;
1636 			offset = inet6_opt_get_val(databuf, offset,
1637 						   &value2, sizeof(value2));
1638 			printf("    Router Alert Opt: Type %u\n",
1639 			    ntohs(value2));
1640 			break;
1641 		default:
1642 			printf("    Received Opt %u len %lu\n",
1643 			    type, (unsigned long)len);
1644 			break;
1645 		}
1646 	}
1647 	return;
1648 }
1649 
1650 static void
1651 pr_rthdr(void *extbuf)
1652 {
1653 	struct in6_addr *in6;
1654 	char ntopbuf[INET6_ADDRSTRLEN];
1655 	struct ip6_rthdr *rh = (struct ip6_rthdr *)extbuf;
1656 	int i, segments;
1657 
1658 	/* print fixed part of the header */
1659 	printf("nxt %u, len %u (%d bytes), type %u, ", rh->ip6r_nxt,
1660 	    rh->ip6r_len, (rh->ip6r_len + 1) << 3, rh->ip6r_type);
1661 	if ((segments = inet6_rth_segments(extbuf)) >= 0)
1662 		printf("%d segments, ", segments);
1663 	else
1664 		printf("segments unknown, ");
1665 	printf("%d left\n", rh->ip6r_segleft);
1666 
1667 	for (i = 0; i < segments; i++) {
1668 		in6 = inet6_rth_getaddr(extbuf, i);
1669 		if (in6 == NULL)
1670 			printf("   [%d]<NULL>\n", i);
1671 		else {
1672 			if (!inet_ntop(AF_INET6, in6, ntopbuf,
1673 			    sizeof(ntopbuf)))
1674 				strlcpy(ntopbuf, "?", sizeof(ntopbuf));
1675 			printf("   [%d]%s\n", i, ntopbuf);
1676 		}
1677 	}
1678 
1679 	return;
1680 
1681 }
1682 
1683 static int
1684 pr_bitrange(u_int32_t v, int soff, int ii)
1685 {
1686 	int off;
1687 	int i;
1688 
1689 	off = 0;
1690 	while (off < 32) {
1691 		/* shift till we have 0x01 */
1692 		if ((v & 0x01) == 0) {
1693 			if (ii > 1)
1694 				printf("-%u", soff + off - 1);
1695 			ii = 0;
1696 			switch (v & 0x0f) {
1697 			case 0x00:
1698 				v >>= 4;
1699 				off += 4;
1700 				continue;
1701 			case 0x08:
1702 				v >>= 3;
1703 				off += 3;
1704 				continue;
1705 			case 0x04: case 0x0c:
1706 				v >>= 2;
1707 				off += 2;
1708 				continue;
1709 			default:
1710 				v >>= 1;
1711 				off += 1;
1712 				continue;
1713 			}
1714 		}
1715 
1716 		/* we have 0x01 with us */
1717 		for (i = 0; i < 32 - off; i++) {
1718 			if ((v & (0x01 << i)) == 0)
1719 				break;
1720 		}
1721 		if (!ii)
1722 			printf(" %u", soff + off);
1723 		ii += i;
1724 		v >>= i; off += i;
1725 	}
1726 	return ii;
1727 }
1728 
1729 static void
1730 pr_suptypes(struct icmp6_nodeinfo *ni /* ni->qtype must be SUPTYPES */,
1731 	    size_t nilen)
1732 {
1733 	size_t clen;
1734 	u_int32_t v;
1735 	const u_char *cp, *end;
1736 	u_int16_t cur;
1737 	struct cbit {
1738 		u_int16_t words;	/*32bit count*/
1739 		u_int16_t skip;
1740 	} cbit;
1741 #define MAXQTYPES	(1 << 16)
1742 	size_t off;
1743 	int b;
1744 
1745 	cp = (u_char *)(ni + 1);
1746 	end = ((u_char *)ni) + nilen;
1747 	cur = 0;
1748 	b = 0;
1749 
1750 	printf("NodeInfo Supported Qtypes");
1751 	if (options & F_VERBOSE) {
1752 		if (ni->ni_flags & NI_SUPTYPE_FLAG_COMPRESS)
1753 			printf(", compressed bitmap");
1754 		else
1755 			printf(", raw bitmap");
1756 	}
1757 
1758 	while (cp < end) {
1759 		size_t skip = 0;
1760 		clen = (size_t)(end - cp);
1761 		if ((ni->ni_flags & NI_SUPTYPE_FLAG_COMPRESS) == 0) {
1762 			if (clen == 0 || clen > MAXQTYPES / 8 ||
1763 			    clen % sizeof(v)) {
1764 				printf("???");
1765 				return;
1766 			}
1767 		} else {
1768 			if (clen < sizeof(cbit) || clen % sizeof(v))
1769 				return;
1770 			memcpy(&cbit, cp, sizeof(cbit));
1771 			if (sizeof(cbit) + ntohs(cbit.words) * sizeof(v) >
1772 			    clen)
1773 				return;
1774 			cp += sizeof(cbit);
1775 			clen = ntohs(cbit.words) * sizeof(v);
1776 			skip = (size_t)ntohs(cbit.skip) * 32;
1777 			if (cur + clen * 8 + skip > MAXQTYPES)
1778 				return;
1779 		}
1780 
1781 		for (off = 0; off < clen; off += sizeof(v)) {
1782 			memcpy(&v, cp + off, sizeof(v));
1783 			v = (u_int32_t)ntohl(v);
1784 			b = pr_bitrange(v, (int)(cur + off * 8), b);
1785 		}
1786 		/* flush the remaining bits */
1787 		b = pr_bitrange(0, (int)(cur + off * 8), b);
1788 
1789 		cp += clen;
1790 		cur += clen * 8 + skip;
1791 	}
1792 }
1793 
1794 static void
1795 pr_nodeaddr(struct icmp6_nodeinfo *ni, /* ni->qtype must be NODEADDR */
1796 	    int nilen)
1797 {
1798 	u_char *cp = (u_char *)(ni + 1);
1799 	char ntop_buf[INET6_ADDRSTRLEN];
1800 	int withttl = 0;
1801 
1802 	nilen -= sizeof(struct icmp6_nodeinfo);
1803 
1804 	if (options & F_VERBOSE) {
1805 		switch (ni->ni_code) {
1806 		case ICMP6_NI_REFUSED:
1807 			printf("refused");
1808 			break;
1809 		case ICMP6_NI_UNKNOWN:
1810 			printf("unknown qtype");
1811 			break;
1812 		}
1813 		if (ni->ni_flags & NI_NODEADDR_FLAG_TRUNCATE)
1814 			printf(" truncated");
1815 	}
1816 	putchar('\n');
1817 	if (nilen <= 0)
1818 		printf("  no address\n");
1819 
1820 	/*
1821 	 * In icmp-name-lookups 05 and later, TTL of each returned address
1822 	 * is contained in the resposne. We try to detect the version
1823 	 * by the length of the data, but note that the detection algorithm
1824 	 * is incomplete. We assume the latest draft by default.
1825 	 */
1826 	if (nilen % (sizeof(u_int32_t) + sizeof(struct in6_addr)) == 0)
1827 		withttl = 1;
1828 	while (nilen > 0) {
1829 		u_int32_t ttl = 0;
1830 
1831 		if (withttl) {
1832 			/* XXX: alignment? */
1833 			ttl = (u_int32_t)ntohl(*(u_int32_t *)cp);
1834 			cp += sizeof(u_int32_t);
1835 			nilen -= sizeof(u_int32_t);
1836 		}
1837 
1838 		if (inet_ntop(AF_INET6, cp, ntop_buf, sizeof(ntop_buf)) ==
1839 		    NULL)
1840 			strlcpy(ntop_buf, "?", sizeof(ntop_buf));
1841 		printf("  %s", ntop_buf);
1842 		if (withttl) {
1843 			if (ttl == 0xffffffff) {
1844 				/*
1845 				 * XXX: can this convention be applied to all
1846 				 * type of TTL (i.e. non-ND TTL)?
1847 				 */
1848 				printf("(TTL=infty)");
1849 			}
1850 			else
1851 				printf("(TTL=%u)", ttl);
1852 		}
1853 		putchar('\n');
1854 
1855 		nilen -= sizeof(struct in6_addr);
1856 		cp += sizeof(struct in6_addr);
1857 	}
1858 }
1859 
1860 static int
1861 get_hoplim(struct msghdr *mhdr)
1862 {
1863 	struct cmsghdr *cm;
1864 
1865 	for (cm = (struct cmsghdr *)CMSG_FIRSTHDR(mhdr); cm;
1866 	     cm = (struct cmsghdr *)CMSG_NXTHDR(mhdr, cm)) {
1867 		if (cm->cmsg_len == 0)
1868 			return(-1);
1869 
1870 		if (cm->cmsg_level == IPPROTO_IPV6 &&
1871 		    cm->cmsg_type == IPV6_HOPLIMIT &&
1872 		    cm->cmsg_len == CMSG_LEN(sizeof(int)))
1873 			return(*(int *)CMSG_DATA(cm));
1874 	}
1875 
1876 	return(-1);
1877 }
1878 
1879 static struct in6_pktinfo *
1880 get_rcvpktinfo(struct msghdr *mhdr)
1881 {
1882 	struct cmsghdr *cm;
1883 
1884 	for (cm = (struct cmsghdr *)CMSG_FIRSTHDR(mhdr); cm;
1885 	     cm = (struct cmsghdr *)CMSG_NXTHDR(mhdr, cm)) {
1886 		if (cm->cmsg_len == 0)
1887 			return(NULL);
1888 
1889 		if (cm->cmsg_level == IPPROTO_IPV6 &&
1890 		    cm->cmsg_type == IPV6_PKTINFO &&
1891 		    cm->cmsg_len == CMSG_LEN(sizeof(struct in6_pktinfo)))
1892 			return((struct in6_pktinfo *)CMSG_DATA(cm));
1893 	}
1894 
1895 	return(NULL);
1896 }
1897 
1898 static int
1899 get_pathmtu(struct msghdr *mhdr)
1900 {
1901 #ifdef IPV6_RECVPATHMTU
1902 	struct cmsghdr *cm;
1903 	struct ip6_mtuinfo *mtuctl = NULL;
1904 
1905 	for (cm = (struct cmsghdr *)CMSG_FIRSTHDR(mhdr); cm;
1906 	     cm = (struct cmsghdr *)CMSG_NXTHDR(mhdr, cm)) {
1907 		if (cm->cmsg_len == 0)
1908 			return(0);
1909 
1910 		if (cm->cmsg_level == IPPROTO_IPV6 &&
1911 		    cm->cmsg_type == IPV6_PATHMTU &&
1912 		    cm->cmsg_len == CMSG_LEN(sizeof(struct ip6_mtuinfo))) {
1913 			mtuctl = (struct ip6_mtuinfo *)CMSG_DATA(cm);
1914 
1915 			/*
1916 			 * If the notified destination is different from
1917 			 * the one we are pinging, just ignore the info.
1918 			 * We check the scope ID only when both notified value
1919 			 * and our own value have non-0 values, because we may
1920 			 * have used the default scope zone ID for sending,
1921 			 * in which case the scope ID value is 0.
1922 			 */
1923 			if (!IN6_ARE_ADDR_EQUAL(&mtuctl->ip6m_addr.sin6_addr,
1924 						&dst.sin6_addr) ||
1925 			    (mtuctl->ip6m_addr.sin6_scope_id &&
1926 			     dst.sin6_scope_id &&
1927 			     mtuctl->ip6m_addr.sin6_scope_id !=
1928 			     dst.sin6_scope_id)) {
1929 				if ((options & F_VERBOSE) != 0) {
1930 					printf("path MTU for %s is notified. "
1931 					       "(ignored)\n",
1932 					   pr_addr((struct sockaddr *)&mtuctl->ip6m_addr,
1933 					   sizeof(mtuctl->ip6m_addr)));
1934 				}
1935 				return(0);
1936 			}
1937 
1938 			/*
1939 			 * Ignore an invalid MTU. XXX: can we just believe
1940 			 * the kernel check?
1941 			 */
1942 			if (mtuctl->ip6m_mtu < IPV6_MMTU)
1943 				return(0);
1944 
1945 			/* notification for our destination. return the MTU. */
1946 			return((int)mtuctl->ip6m_mtu);
1947 		}
1948 	}
1949 #endif
1950 	return(0);
1951 }
1952 
1953 /*
1954  * tvsub --
1955  *	Subtract 2 timeval structs:  out = out - in.  Out is assumed to
1956  * be >= in.
1957  */
1958 static void
1959 tvsub(struct timeval *out, struct timeval *in)
1960 {
1961 	if ((out->tv_usec -= in->tv_usec) < 0) {
1962 		--out->tv_sec;
1963 		out->tv_usec += 1000000;
1964 	}
1965 	out->tv_sec -= in->tv_sec;
1966 }
1967 
1968 /*
1969  * onsigexit --
1970  */
1971 static void
1972 onsigexit(int sig)
1973 {
1974 	summary();
1975 
1976 	if (sig == SIGINT) {
1977 		(void)signal(SIGINT, SIG_DFL);
1978 		(void)kill(getpid(), SIGINT);
1979 	}
1980 
1981 	exit(1);
1982 }
1983 
1984 /*
1985  * summary --
1986  *	Print out statistics.
1987  */
1988 static void
1989 summary(void)
1990 {
1991 
1992 	printf("\n--- %s ping6 statistics ---\n", hostname);
1993 	printf("%ld packets transmitted, ", ntransmitted);
1994 	printf("%ld packets received, ", nreceived);
1995 	if (nrepeats)
1996 		printf("+%ld duplicates, ", nrepeats);
1997 	if (ntransmitted) {
1998 		if (nreceived > ntransmitted)
1999 			printf("-- somebody's duplicating packets!");
2000 		else
2001 			printf("%.1f%% packet loss",
2002 			    ((((double)ntransmitted - nreceived) * 100.0) /
2003 			    ntransmitted));
2004 	}
2005 	(void)putchar('\n');
2006 	if (nreceived && timing) {
2007 		/* Only display average to microseconds */
2008 		double num = nreceived + nrepeats;
2009 		double dev, avg;
2010 		if (num > 1) {
2011 			avg = tsum / num;
2012 			dev = sqrt((tsumsq - num * avg * avg) / (num - 1));
2013 		} else {
2014 			avg = tsum;
2015 			dev = 0.0;
2016 		}
2017 		printf(
2018 		    "round-trip min/avg/max/std-dev = %.3f/%.3f/%.3f/%.3f ms\n",
2019 		    tmin, avg, tmax, dev);
2020 		(void)fflush(stdout);
2021 	}
2022 	(void)fflush(stdout);
2023 }
2024 
2025 /*subject type*/
2026 static const char *niqcode[] = {
2027 	"IPv6 address",
2028 	"DNS label",	/*or empty*/
2029 	"IPv4 address",
2030 };
2031 
2032 /*result code*/
2033 static const char *nircode[] = {
2034 	"Success", "Refused", "Unknown",
2035 };
2036 
2037 
2038 /*
2039  * pr_icmph --
2040  *	Print a descriptive string about an ICMP header.
2041  */
2042 static void
2043 pr_icmph(struct icmp6_hdr *icp, u_char *end)
2044 {
2045 	char ntop_buf[INET6_ADDRSTRLEN];
2046 	struct nd_redirect *red;
2047 	struct icmp6_nodeinfo *ni;
2048 	char dnsname[MAXDNAME + 1];
2049 	const u_char *cp;
2050 	size_t l;
2051 
2052 	switch (icp->icmp6_type) {
2053 	case ICMP6_DST_UNREACH:
2054 		switch (icp->icmp6_code) {
2055 		case ICMP6_DST_UNREACH_NOROUTE:
2056 			printf("No Route to Destination\n");
2057 			break;
2058 		case ICMP6_DST_UNREACH_ADMIN:
2059 			printf("Destination Administratively "
2060 			    "Unreachable\n");
2061 			break;
2062 		case ICMP6_DST_UNREACH_BEYONDSCOPE:
2063 			printf("Destination Unreachable Beyond Scope\n");
2064 			break;
2065 		case ICMP6_DST_UNREACH_ADDR:
2066 			printf("Destination Host Unreachable\n");
2067 			break;
2068 		case ICMP6_DST_UNREACH_NOPORT:
2069 			printf("Destination Port Unreachable\n");
2070 			break;
2071 		default:
2072 			printf("Destination Unreachable, Bad Code: %d\n",
2073 			    icp->icmp6_code);
2074 			break;
2075 		}
2076 		/* Print returned IP header information */
2077 		pr_retip((struct ip6_hdr *)(icp + 1), end);
2078 		break;
2079 	case ICMP6_PACKET_TOO_BIG:
2080 		printf("Packet too big mtu = %d\n",
2081 		    (int)ntohl(icp->icmp6_mtu));
2082 		pr_retip((struct ip6_hdr *)(icp + 1), end);
2083 		break;
2084 	case ICMP6_TIME_EXCEEDED:
2085 		switch (icp->icmp6_code) {
2086 		case ICMP6_TIME_EXCEED_TRANSIT:
2087 			printf("Time to live exceeded\n");
2088 			break;
2089 		case ICMP6_TIME_EXCEED_REASSEMBLY:
2090 			printf("Frag reassembly time exceeded\n");
2091 			break;
2092 		default:
2093 			printf("Time exceeded, Bad Code: %d\n",
2094 			    icp->icmp6_code);
2095 			break;
2096 		}
2097 		pr_retip((struct ip6_hdr *)(icp + 1), end);
2098 		break;
2099 	case ICMP6_PARAM_PROB:
2100 		printf("Parameter problem: ");
2101 		switch (icp->icmp6_code) {
2102 		case ICMP6_PARAMPROB_HEADER:
2103 			printf("Erroneous Header ");
2104 			break;
2105 		case ICMP6_PARAMPROB_NEXTHEADER:
2106 			printf("Unknown Nextheader ");
2107 			break;
2108 		case ICMP6_PARAMPROB_OPTION:
2109 			printf("Unrecognized Option ");
2110 			break;
2111 		case ICMP6_PARAMPROB_FRAGMENT:
2112 			printf("First Fragment Has Incomplete Chain ");
2113 			break;
2114 		default:
2115 			printf("Bad code(%d) ", icp->icmp6_code);
2116 			break;
2117 		}
2118 		printf("pointer = 0x%02x\n",
2119 		    (u_int32_t)ntohl(icp->icmp6_pptr));
2120 		pr_retip((struct ip6_hdr *)(icp + 1), end);
2121 		break;
2122 	case ICMP6_ECHO_REQUEST:
2123 		printf("Echo Request");
2124 		/* XXX ID + Seq + Data */
2125 		break;
2126 	case ICMP6_ECHO_REPLY:
2127 		printf("Echo Reply");
2128 		/* XXX ID + Seq + Data */
2129 		break;
2130 	case ICMP6_MEMBERSHIP_QUERY:
2131 		printf("Listener Query");
2132 		break;
2133 	case ICMP6_MEMBERSHIP_REPORT:
2134 		printf("Listener Report");
2135 		break;
2136 	case ICMP6_MEMBERSHIP_REDUCTION:
2137 		printf("Listener Done");
2138 		break;
2139 	case ND_ROUTER_SOLICIT:
2140 		printf("Router Solicitation");
2141 		break;
2142 	case ND_ROUTER_ADVERT:
2143 		printf("Router Advertisement");
2144 		break;
2145 	case ND_NEIGHBOR_SOLICIT:
2146 		printf("Neighbor Solicitation");
2147 		break;
2148 	case ND_NEIGHBOR_ADVERT:
2149 		printf("Neighbor Advertisement");
2150 		break;
2151 	case ND_REDIRECT:
2152 		red = (struct nd_redirect *)icp;
2153 		printf("Redirect\n");
2154 		if (!inet_ntop(AF_INET6, &red->nd_rd_dst, ntop_buf,
2155 		    sizeof(ntop_buf)))
2156 			strlcpy(ntop_buf, "?", sizeof(ntop_buf));
2157 		printf("Destination: %s", ntop_buf);
2158 		if (!inet_ntop(AF_INET6, &red->nd_rd_target, ntop_buf,
2159 		    sizeof(ntop_buf)))
2160 			strlcpy(ntop_buf, "?", sizeof(ntop_buf));
2161 		printf(" New Target: %s", ntop_buf);
2162 		break;
2163 	case ICMP6_NI_QUERY:
2164 		printf("Node Information Query");
2165 		/* XXX ID + Seq + Data */
2166 		ni = (struct icmp6_nodeinfo *)icp;
2167 		l = end - (u_char *)(ni + 1);
2168 		printf(", ");
2169 		switch (ntohs(ni->ni_qtype)) {
2170 		case NI_QTYPE_NOOP:
2171 			printf("NOOP");
2172 			break;
2173 		case NI_QTYPE_SUPTYPES:
2174 			printf("Supported qtypes");
2175 			break;
2176 		case NI_QTYPE_FQDN:
2177 			printf("DNS name");
2178 			break;
2179 		case NI_QTYPE_NODEADDR:
2180 			printf("nodeaddr");
2181 			break;
2182 		case NI_QTYPE_IPV4ADDR:
2183 			printf("IPv4 nodeaddr");
2184 			break;
2185 		default:
2186 			printf("unknown qtype");
2187 			break;
2188 		}
2189 		if (options & F_VERBOSE) {
2190 			switch (ni->ni_code) {
2191 			case ICMP6_NI_SUBJ_IPV6:
2192 				if (l == sizeof(struct in6_addr) &&
2193 				    inet_ntop(AF_INET6, ni + 1, ntop_buf,
2194 				    sizeof(ntop_buf)) != NULL) {
2195 					printf(", subject=%s(%s)",
2196 					    niqcode[ni->ni_code], ntop_buf);
2197 				} else {
2198 #if 1
2199 					/* backward compat to -W */
2200 					printf(", oldfqdn");
2201 #else
2202 					printf(", invalid");
2203 #endif
2204 				}
2205 				break;
2206 			case ICMP6_NI_SUBJ_FQDN:
2207 				if (end == (u_char *)(ni + 1)) {
2208 					printf(", no subject");
2209 					break;
2210 				}
2211 				printf(", subject=%s", niqcode[ni->ni_code]);
2212 				cp = (const u_char *)(ni + 1);
2213 				if (dnsdecode(&cp, end, NULL, dnsname,
2214 				    sizeof(dnsname)) != NULL)
2215 					printf("(%s)", dnsname);
2216 				else
2217 					printf("(invalid)");
2218 				break;
2219 			case ICMP6_NI_SUBJ_IPV4:
2220 				if (l == sizeof(struct in_addr) &&
2221 				    inet_ntop(AF_INET, ni + 1, ntop_buf,
2222 				    sizeof(ntop_buf)) != NULL) {
2223 					printf(", subject=%s(%s)",
2224 					    niqcode[ni->ni_code], ntop_buf);
2225 				} else
2226 					printf(", invalid");
2227 				break;
2228 			default:
2229 				printf(", invalid");
2230 				break;
2231 			}
2232 		}
2233 		break;
2234 	case ICMP6_NI_REPLY:
2235 		printf("Node Information Reply");
2236 		/* XXX ID + Seq + Data */
2237 		ni = (struct icmp6_nodeinfo *)icp;
2238 		printf(", ");
2239 		switch (ntohs(ni->ni_qtype)) {
2240 		case NI_QTYPE_NOOP:
2241 			printf("NOOP");
2242 			break;
2243 		case NI_QTYPE_SUPTYPES:
2244 			printf("Supported qtypes");
2245 			break;
2246 		case NI_QTYPE_FQDN:
2247 			printf("DNS name");
2248 			break;
2249 		case NI_QTYPE_NODEADDR:
2250 			printf("nodeaddr");
2251 			break;
2252 		case NI_QTYPE_IPV4ADDR:
2253 			printf("IPv4 nodeaddr");
2254 			break;
2255 		default:
2256 			printf("unknown qtype");
2257 			break;
2258 		}
2259 		if (options & F_VERBOSE) {
2260 			if (ni->ni_code >= sizeof(nircode) / sizeof(nircode[0]))
2261 				printf(", invalid");
2262 			else
2263 				printf(", %s", nircode[ni->ni_code]);
2264 		}
2265 		break;
2266 	default:
2267 		printf("Bad ICMP type: %d", icp->icmp6_type);
2268 	}
2269 }
2270 
2271 /*
2272  * pr_iph --
2273  *	Print an IP6 header.
2274  */
2275 static void
2276 pr_iph(struct ip6_hdr *ip6)
2277 {
2278 	u_int32_t flow = ip6->ip6_flow & IPV6_FLOWLABEL_MASK;
2279 	u_int8_t tc;
2280 	char ntop_buf[INET6_ADDRSTRLEN];
2281 
2282 	tc = *(&ip6->ip6_vfc + 1); /* XXX */
2283 	tc = (tc >> 4) & 0x0f;
2284 	tc |= (ip6->ip6_vfc << 4);
2285 
2286 	printf("Vr TC  Flow Plen Nxt Hlim\n");
2287 	printf(" %1x %02x %05x %04x  %02x   %02x\n",
2288 	    (ip6->ip6_vfc & IPV6_VERSION_MASK) >> 4, tc, (u_int32_t)ntohl(flow),
2289 	    ntohs(ip6->ip6_plen), ip6->ip6_nxt, ip6->ip6_hlim);
2290 	if (!inet_ntop(AF_INET6, &ip6->ip6_src, ntop_buf, sizeof(ntop_buf)))
2291 		strlcpy(ntop_buf, "?", sizeof(ntop_buf));
2292 	printf("%s->", ntop_buf);
2293 	if (!inet_ntop(AF_INET6, &ip6->ip6_dst, ntop_buf, sizeof(ntop_buf)))
2294 		strlcpy(ntop_buf, "?", sizeof(ntop_buf));
2295 	printf("%s\n", ntop_buf);
2296 }
2297 
2298 /*
2299  * pr_addr --
2300  *	Return an ascii host address as a dotted quad and optionally with
2301  * a hostname.
2302  */
2303 static const char *
2304 pr_addr(struct sockaddr *addr, int addrlen)
2305 {
2306 	static char buf[NI_MAXHOST];
2307 	int flag = 0;
2308 
2309 	if ((options & F_HOSTNAME) == 0)
2310 		flag |= NI_NUMERICHOST;
2311 
2312 	if (getnameinfo(addr, addrlen, buf, sizeof(buf), NULL, 0, flag) == 0)
2313 		return (buf);
2314 	else
2315 		return "?";
2316 }
2317 
2318 /*
2319  * pr_retip --
2320  *	Dump some info on a returned (via ICMPv6) IPv6 packet.
2321  */
2322 static void
2323 pr_retip(struct ip6_hdr *ip6, u_char *end)
2324 {
2325 	u_char *cp = (u_char *)ip6, nh;
2326 	int hlen;
2327 
2328 	if (end - (u_char *)ip6 < (intptr_t)sizeof(*ip6)) {
2329 		printf("IP6");
2330 		goto trunc;
2331 	}
2332 	pr_iph(ip6);
2333 	hlen = sizeof(*ip6);
2334 
2335 	nh = ip6->ip6_nxt;
2336 	cp += hlen;
2337 	while (end - cp >= 8) {
2338 		switch (nh) {
2339 		case IPPROTO_HOPOPTS:
2340 			printf("HBH ");
2341 			hlen = (((struct ip6_hbh *)cp)->ip6h_len+1) << 3;
2342 			nh = ((struct ip6_hbh *)cp)->ip6h_nxt;
2343 			break;
2344 		case IPPROTO_DSTOPTS:
2345 			printf("DSTOPT ");
2346 			hlen = (((struct ip6_dest *)cp)->ip6d_len+1) << 3;
2347 			nh = ((struct ip6_dest *)cp)->ip6d_nxt;
2348 			break;
2349 		case IPPROTO_FRAGMENT:
2350 			printf("FRAG ");
2351 			hlen = sizeof(struct ip6_frag);
2352 			nh = ((struct ip6_frag *)cp)->ip6f_nxt;
2353 			break;
2354 		case IPPROTO_ROUTING:
2355 			printf("RTHDR ");
2356 			hlen = (((struct ip6_rthdr *)cp)->ip6r_len+1) << 3;
2357 			nh = ((struct ip6_rthdr *)cp)->ip6r_nxt;
2358 			break;
2359 #ifdef IPSEC
2360 		case IPPROTO_AH:
2361 			printf("AH ");
2362 			hlen = (((struct ip6_ext *)cp)->ip6e_len+2) << 2;
2363 			nh = ((struct ip6_ext *)cp)->ip6e_nxt;
2364 			break;
2365 #endif
2366 		case IPPROTO_ICMPV6:
2367 			printf("ICMP6: type = %d, code = %d\n",
2368 			    *cp, *(cp + 1));
2369 			return;
2370 		case IPPROTO_ESP:
2371 			printf("ESP\n");
2372 			return;
2373 		case IPPROTO_TCP:
2374 			printf("TCP: from port %u, to port %u (decimal)\n",
2375 			    (*cp * 256 + *(cp + 1)),
2376 			    (*(cp + 2) * 256 + *(cp + 3)));
2377 			return;
2378 		case IPPROTO_UDP:
2379 			printf("UDP: from port %u, to port %u (decimal)\n",
2380 			    (*cp * 256 + *(cp + 1)),
2381 			    (*(cp + 2) * 256 + *(cp + 3)));
2382 			return;
2383 		default:
2384 			printf("Unknown Header(%d)\n", nh);
2385 			return;
2386 		}
2387 
2388 		if ((cp += hlen) >= end)
2389 			goto trunc;
2390 	}
2391 	if (end - cp < 8)
2392 		goto trunc;
2393 
2394 	putchar('\n');
2395 	return;
2396 
2397   trunc:
2398 	printf("...\n");
2399 	return;
2400 }
2401 
2402 static void
2403 fill(char *bp, char *patp)
2404 {
2405 	int ii, jj, kk;
2406 	int pat[16];
2407 	char *cp;
2408 
2409 	for (cp = patp; *cp; cp++)
2410 		if (!isxdigit((unsigned char)*cp))
2411 			errx(1, "patterns must be specified as hex digits");
2412 	ii = sscanf(patp,
2413 	    "%2x%2x%2x%2x%2x%2x%2x%2x%2x%2x%2x%2x%2x%2x%2x%2x",
2414 	    &pat[0], &pat[1], &pat[2], &pat[3], &pat[4], &pat[5], &pat[6],
2415 	    &pat[7], &pat[8], &pat[9], &pat[10], &pat[11], &pat[12],
2416 	    &pat[13], &pat[14], &pat[15]);
2417 
2418 /* xxx */
2419 	if (ii > 0)
2420 		for (kk = 0;
2421 		    kk <= (int)(MAXDATALEN - (8 + sizeof(struct tv32) + ii));
2422 		    kk += ii)
2423 			for (jj = 0; jj < ii; ++jj)
2424 				bp[jj + kk] = pat[jj];
2425 	if (!(options & F_QUIET)) {
2426 		printf("PATTERN: 0x");
2427 		for (jj = 0; jj < ii; ++jj)
2428 			printf("%02x", bp[jj] & 0xFF);
2429 		printf("\n");
2430 	}
2431 }
2432 
2433 #if defined(IPSEC) && defined(IPSEC_POLICY_IPSEC)
2434 static int
2435 setpolicy(int so, char *policy)
2436 {
2437 	char *buf;
2438 
2439 	if (policy == NULL)
2440 		return 0;	/* ignore */
2441 
2442 	buf = ipsec_set_policy(policy, strlen(policy));
2443 	if (buf == NULL)
2444 		errx(1, "%s", ipsec_strerror());
2445 	if (prog_setsockopt(s, IPPROTO_IPV6, IPV6_IPSEC_POLICY, buf,
2446 	    ipsec_get_policylen(buf)) < 0)
2447 		warnx("Unable to set IPsec policy");
2448 	free(buf);
2449 
2450 	return 0;
2451 }
2452 #endif
2453 
2454 static char *
2455 nigroup(char *name)
2456 {
2457 	char *p;
2458 	char *q;
2459 	MD5_CTX ctxt;
2460 	u_int8_t digest[16];
2461 	u_int8_t c;
2462 	size_t l;
2463 	char hbuf[NI_MAXHOST];
2464 	struct in6_addr in6;
2465 
2466 	p = strchr(name, '.');
2467 	if (!p)
2468 		p = name + strlen(name);
2469 	l = p - name;
2470 	if (l > 63 || l > sizeof(hbuf) - 1)
2471 		return NULL;	/*label too long*/
2472 	strncpy(hbuf, name, l);
2473 	hbuf[(int)l] = '\0';
2474 
2475 	for (q = name; *q; q++) {
2476 		if (isupper(*(unsigned char *)q))
2477 			*q = tolower(*(unsigned char *)q);
2478 	}
2479 
2480 	/* generate 8 bytes of pseudo-random value. */
2481 	memset(&ctxt, 0, sizeof(ctxt));
2482 	MD5Init(&ctxt);
2483 	c = l & 0xff;
2484 	MD5Update(&ctxt, &c, sizeof(c));
2485 	MD5Update(&ctxt, (unsigned char *)name, l);
2486 	MD5Final(digest, &ctxt);
2487 
2488 	if (inet_pton(AF_INET6, "ff02::2:0000:0000", &in6) != 1)
2489 		return NULL;	/*XXX*/
2490 	bcopy(digest, &in6.s6_addr[12], 4);
2491 
2492 	if (inet_ntop(AF_INET6, &in6, hbuf, sizeof(hbuf)) == NULL)
2493 		return NULL;
2494 
2495 	return strdup(hbuf);
2496 }
2497 
2498 static double
2499 timespec_to_sec(const struct timespec *tp)
2500 {
2501 	return tp->tv_sec + tp->tv_nsec / 1000000000.0;
2502 }
2503 
2504 /*
2505  * compute the difference of two timespecs in seconds
2506  */
2507 static double
2508 diffsec(struct timespec *timenow,
2509 	struct timespec *then)
2510 {
2511 	if (timenow->tv_sec == 0)
2512 		return -1;
2513 	return (timenow->tv_sec - then->tv_sec)
2514 	    * 1.0 + (timenow->tv_nsec - then->tv_nsec) / 1000000000.0;
2515 }
2516 
2517 static void
2518 usage(void)
2519 {
2520 	fprintf(stderr,
2521 	    "usage: ping6 [-dfHmNnqtvWw] [-a addrtype] [-b bufsize]\n"
2522 	    "\t[-c count] [-g gateway] [-h hoplimit] [-I interface]\n"
2523 	    "\t[-i wait] [-l preload]"
2524 #if defined(IPSEC) && defined(IPSEC_POLICY_IPSEC)
2525 	    " [-P policy]"
2526 #endif
2527             "\n"
2528 	    "\t[-p pattern] [-S sourceaddr] [-s packetsize] [-X deadline]\n"
2529 	    "\t[-x maxwait] host\n");
2530 	exit(1);
2531 }
2532