xref: /freebsd/usr.sbin/traceroute6/traceroute6.c (revision 77a0943ded95b9e6438f7db70c4a28e4d93946d4)
1 /*	$KAME: traceroute6.c,v 1.32 2000/07/07 12:21:34 itojun Exp $	*/
2 
3 /*
4  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the project nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 /*-
33  * Copyright (c) 1990, 1993
34  *	The Regents of the University of California.  All rights reserved.
35  *
36  * This code is derived from software contributed to Berkeley by
37  * Van Jacobson.
38  *
39  * Redistribution and use in source and binary forms, with or without
40  * modification, are permitted provided that the following conditions
41  * are met:
42  * 1. Redistributions of source code must retain the above copyright
43  *    notice, this list of conditions and the following disclaimer.
44  * 2. Redistributions in binary form must reproduce the above copyright
45  *    notice, this list of conditions and the following disclaimer in the
46  *    documentation and/or other materials provided with the distribution.
47  * 3. All advertising materials mentioning features or use of this software
48  *    must display the following acknowledgement:
49  *	This product includes software developed by the University of
50  *	California, Berkeley and its contributors.
51  * 4. Neither the name of the University nor the names of its contributors
52  *    may be used to endorse or promote products derived from this software
53  *    without specific prior written permission.
54  *
55  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
56  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
57  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
58  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
59  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
60  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
61  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
62  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
63  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
64  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
65  * SUCH DAMAGE.
66  */
67 
68 #ifndef lint
69 static char copyright[] =
70 "@(#) Copyright (c) 1990, 1993\n\
71 	The Regents of the University of California.  All rights reserved.\n";
72 #endif /* not lint */
73 
74 #ifndef lint
75 #if 0
76 static char sccsid[] = "@(#)traceroute.c	8.1 (Berkeley) 6/6/93";
77 #endif
78 static const char rcsid[] =
79   "$FreeBSD$";
80 #endif /* not lint */
81 
82 /*
83  * traceroute host  - trace the route ip packets follow going to "host".
84  *
85  * Attempt to trace the route an ip packet would follow to some
86  * internet host.  We find out intermediate hops by launching probe
87  * packets with a small ttl (time to live) then listening for an
88  * icmp "time exceeded" reply from a gateway.  We start our probes
89  * with a ttl of one and increase by one until we get an icmp "port
90  * unreachable" (which means we got to "host") or hit a max (which
91  * defaults to 30 hops & can be changed with the -m flag).  Three
92  * probes (change with -q flag) are sent at each ttl setting and a
93  * line is printed showing the ttl, address of the gateway and
94  * round trip time of each probe.  If the probe answers come from
95  * different gateways, the address of each responding system will
96  * be printed.  If there is no response within a 5 sec. timeout
97  * interval (changed with the -w flag), a "*" is printed for that
98  * probe.
99  *
100  * Probe packets are UDP format.  We don't want the destination
101  * host to process them so the destination port is set to an
102  * unlikely value (if some clod on the destination is using that
103  * value, it can be changed with the -p flag).
104  *
105  * A sample use might be:
106  *
107  *     [yak 71]% traceroute nis.nsf.net.
108  *     traceroute to nis.nsf.net (35.1.1.48), 30 hops max, 56 byte packet
109  *      1  helios.ee.lbl.gov (128.3.112.1)  19 ms  19 ms  0 ms
110  *      2  lilac-dmc.Berkeley.EDU (128.32.216.1)  39 ms  39 ms  19 ms
111  *      3  lilac-dmc.Berkeley.EDU (128.32.216.1)  39 ms  39 ms  19 ms
112  *      4  ccngw-ner-cc.Berkeley.EDU (128.32.136.23)  39 ms  40 ms  39 ms
113  *      5  ccn-nerif22.Berkeley.EDU (128.32.168.22)  39 ms  39 ms  39 ms
114  *      6  128.32.197.4 (128.32.197.4)  40 ms  59 ms  59 ms
115  *      7  131.119.2.5 (131.119.2.5)  59 ms  59 ms  59 ms
116  *      8  129.140.70.13 (129.140.70.13)  99 ms  99 ms  80 ms
117  *      9  129.140.71.6 (129.140.71.6)  139 ms  239 ms  319 ms
118  *     10  129.140.81.7 (129.140.81.7)  220 ms  199 ms  199 ms
119  *     11  nic.merit.edu (35.1.1.48)  239 ms  239 ms  239 ms
120  *
121  * Note that lines 2 & 3 are the same.  This is due to a buggy
122  * kernel on the 2nd hop system -- lbl-csam.arpa -- that forwards
123  * packets with a zero ttl.
124  *
125  * A more interesting example is:
126  *
127  *     [yak 72]% traceroute allspice.lcs.mit.edu.
128  *     traceroute to allspice.lcs.mit.edu (18.26.0.115), 30 hops max
129  *      1  helios.ee.lbl.gov (128.3.112.1)  0 ms  0 ms  0 ms
130  *      2  lilac-dmc.Berkeley.EDU (128.32.216.1)  19 ms  19 ms  19 ms
131  *      3  lilac-dmc.Berkeley.EDU (128.32.216.1)  39 ms  19 ms  19 ms
132  *      4  ccngw-ner-cc.Berkeley.EDU (128.32.136.23)  19 ms  39 ms  39 ms
133  *      5  ccn-nerif22.Berkeley.EDU (128.32.168.22)  20 ms  39 ms  39 ms
134  *      6  128.32.197.4 (128.32.197.4)  59 ms  119 ms  39 ms
135  *      7  131.119.2.5 (131.119.2.5)  59 ms  59 ms  39 ms
136  *      8  129.140.70.13 (129.140.70.13)  80 ms  79 ms  99 ms
137  *      9  129.140.71.6 (129.140.71.6)  139 ms  139 ms  159 ms
138  *     10  129.140.81.7 (129.140.81.7)  199 ms  180 ms  300 ms
139  *     11  129.140.72.17 (129.140.72.17)  300 ms  239 ms  239 ms
140  *     12  * * *
141  *     13  128.121.54.72 (128.121.54.72)  259 ms  499 ms  279 ms
142  *     14  * * *
143  *     15  * * *
144  *     16  * * *
145  *     17  * * *
146  *     18  ALLSPICE.LCS.MIT.EDU (18.26.0.115)  339 ms  279 ms  279 ms
147  *
148  * (I start to see why I'm having so much trouble with mail to
149  * MIT.)  Note that the gateways 12, 14, 15, 16 & 17 hops away
150  * either don't send ICMP "time exceeded" messages or send them
151  * with a ttl too small to reach us.  14 - 17 are running the
152  * MIT C Gateway code that doesn't send "time exceeded"s.  God
153  * only knows what's going on with 12.
154  *
155  * The silent gateway 12 in the above may be the result of a bug in
156  * the 4.[23]BSD network code (and its derivatives):  4.x (x <= 3)
157  * sends an unreachable message using whatever ttl remains in the
158  * original datagram.  Since, for gateways, the remaining ttl is
159  * zero, the icmp "time exceeded" is guaranteed to not make it back
160  * to us.  The behavior of this bug is slightly more interesting
161  * when it appears on the destination system:
162  *
163  *      1  helios.ee.lbl.gov (128.3.112.1)  0 ms  0 ms  0 ms
164  *      2  lilac-dmc.Berkeley.EDU (128.32.216.1)  39 ms  19 ms  39 ms
165  *      3  lilac-dmc.Berkeley.EDU (128.32.216.1)  19 ms  39 ms  19 ms
166  *      4  ccngw-ner-cc.Berkeley.EDU (128.32.136.23)  39 ms  40 ms  19 ms
167  *      5  ccn-nerif35.Berkeley.EDU (128.32.168.35)  39 ms  39 ms  39 ms
168  *      6  csgw.Berkeley.EDU (128.32.133.254)  39 ms  59 ms  39 ms
169  *      7  * * *
170  *      8  * * *
171  *      9  * * *
172  *     10  * * *
173  *     11  * * *
174  *     12  * * *
175  *     13  rip.Berkeley.EDU (128.32.131.22)  59 ms !  39 ms !  39 ms !
176  *
177  * Notice that there are 12 "gateways" (13 is the final
178  * destination) and exactly the last half of them are "missing".
179  * What's really happening is that rip (a Sun-3 running Sun OS3.5)
180  * is using the ttl from our arriving datagram as the ttl in its
181  * icmp reply.  So, the reply will time out on the return path
182  * (with no notice sent to anyone since icmp's aren't sent for
183  * icmp's) until we probe with a ttl that's at least twice the path
184  * length.  I.e., rip is really only 7 hops away.  A reply that
185  * returns with a ttl of 1 is a clue this problem exists.
186  * Traceroute prints a "!" after the time if the ttl is <= 1.
187  * Since vendors ship a lot of obsolete (DEC's Ultrix, Sun 3.x) or
188  * non-standard (HPUX) software, expect to see this problem
189  * frequently and/or take care picking the target host of your
190  * probes.
191  *
192  * Other possible annotations after the time are !H, !N, !P (got a host,
193  * network or protocol unreachable, respectively), !S or !F (source
194  * route failed or fragmentation needed -- neither of these should
195  * ever occur and the associated gateway is busted if you see one).  If
196  * almost all the probes result in some kind of unreachable, traceroute
197  * will give up and exit.
198  *
199  * Notes
200  * -----
201  * This program must be run by root or be setuid.  (I suggest that
202  * you *don't* make it setuid -- casual use could result in a lot
203  * of unnecessary traffic on our poor, congested nets.)
204  *
205  * This program requires a kernel mod that does not appear in any
206  * system available from Berkeley:  A raw ip socket using proto
207  * IPPROTO_RAW must interpret the data sent as an ip datagram (as
208  * opposed to data to be wrapped in a ip datagram).  See the README
209  * file that came with the source to this program for a description
210  * of the mods I made to /sys/netinet/raw_ip.c.  Your mileage may
211  * vary.  But, again, ANY 4.x (x < 4) BSD KERNEL WILL HAVE TO BE
212  * MODIFIED TO RUN THIS PROGRAM.
213  *
214  * The udp port usage may appear bizarre (well, ok, it is bizarre).
215  * The problem is that an icmp message only contains 8 bytes of
216  * data from the original datagram.  8 bytes is the size of a udp
217  * header so, if we want to associate replies with the original
218  * datagram, the necessary information must be encoded into the
219  * udp header (the ip id could be used but there's no way to
220  * interlock with the kernel's assignment of ip id's and, anyway,
221  * it would have taken a lot more kernel hacking to allow this
222  * code to set the ip id).  So, to allow two or more users to
223  * use traceroute simultaneously, we use this task's pid as the
224  * source port (the high bit is set to move the port number out
225  * of the "likely" range).  To keep track of which probe is being
226  * replied to (so times and/or hop counts don't get confused by a
227  * reply that was delayed in transit), we increment the destination
228  * port number before each probe.
229  *
230  * Don't use this as a coding example.  I was trying to find a
231  * routing problem and this code sort-of popped out after 48 hours
232  * without sleep.  I was amazed it ever compiled, much less ran.
233  *
234  * I stole the idea for this program from Steve Deering.  Since
235  * the first release, I've learned that had I attended the right
236  * IETF working group meetings, I also could have stolen it from Guy
237  * Almes or Matt Mathis.  I don't know (or care) who came up with
238  * the idea first.  I envy the originators' perspicacity and I'm
239  * glad they didn't keep the idea a secret.
240  *
241  * Tim Seaver, Ken Adelman and C. Philip Wood provided bug fixes and/or
242  * enhancements to the original distribution.
243  *
244  * I've hacked up a round-trip-route version of this that works by
245  * sending a loose-source-routed udp datagram through the destination
246  * back to yourself.  Unfortunately, SO many gateways botch source
247  * routing, the thing is almost worthless.  Maybe one day...
248  *
249  *  -- Van Jacobson (van@helios.ee.lbl.gov)
250  *     Tue Dec 20 03:50:13 PST 1988
251  */
252 
253 #include <sys/param.h>
254 #include <sys/time.h>
255 #include <sys/socket.h>
256 #include <sys/uio.h>
257 #include <sys/file.h>
258 #include <sys/ioctl.h>
259 
260 #include <netinet/in.h>
261 
262 #include <arpa/inet.h>
263 
264 #include <netdb.h>
265 #include <stdio.h>
266 #include <err.h>
267 #ifdef HAVE_POLL
268 #include <poll.h>
269 #endif
270 #include <errno.h>
271 #include <stdlib.h>
272 #include <string.h>
273 #include <unistd.h>
274 
275 #include <netinet/ip6.h>
276 #include <netinet/icmp6.h>
277 #include <netinet/udp.h>
278 
279 #ifdef IPSEC
280 #include <net/route.h>
281 #include <netinet6/ipsec.h>
282 #endif
283 
284 #define DUMMY_PORT 10010
285 
286 #define	MAXPACKET	65535	/* max ip packet size */
287 #ifndef MAXHOSTNAMELEN
288 #define MAXHOSTNAMELEN	64
289 #endif
290 
291 #ifndef FD_SET
292 #define NFDBITS         (8*sizeof(fd_set))
293 #define FD_SETSIZE      NFDBITS
294 #define FD_SET(n, p)    ((p)->fds_bits[(n)/NFDBITS] |= (1 << ((n) % NFDBITS)))
295 #define FD_CLR(n, p)    ((p)->fds_bits[(n)/NFDBITS] &= ~(1 << ((n) % NFDBITS)))
296 #define FD_ISSET(n, p)  ((p)->fds_bits[(n)/NFDBITS] & (1 << ((n) % NFDBITS)))
297 #define FD_ZERO(p)      bzero((char *)(p), sizeof(*(p)))
298 #endif
299 
300 #define Fprintf (void)fprintf
301 #define Sprintf (void)sprintf
302 #define Printf (void)printf
303 
304 #ifndef HAVE_GETIPNODEBYNAME
305 #define getipnodebyname(x, y, z, u)	gethostbyname2((x), (y))
306 #define freehostent(x)
307 #endif
308 
309 /*
310  * format of a (udp) probe packet.
311  */
312 struct opacket {
313 	u_char seq;		/* sequence number of this packet */
314 	u_char hops;		/* hop limit of the packet */
315 	struct timeval tv;	/* time packet left */
316 };
317 
318 u_char	packet[512];		/* last inbound (icmp) packet */
319 struct opacket	*outpacket;	/* last output (udp) packet */
320 
321 int	main __P((int, char *[]));
322 int	wait_for_reply __P((int, struct msghdr *));
323 #ifdef IPSEC
324 #ifdef IPSEC_POLICY_IPSEC
325 int	setpolicy __P((int so, char *policy));
326 #endif
327 #endif
328 void	send_probe __P((int, int));
329 struct udphdr *get_udphdr __P((struct ip6_hdr *, u_char *));
330 int	get_hoplim __P((struct msghdr *));
331 double	deltaT __P((struct timeval *, struct timeval *));
332 char	*pr_type __P((int));
333 int	packet_ok __P((struct msghdr *, int, int));
334 void	print __P((struct msghdr *, int));
335 void	tvsub __P((struct timeval *, struct timeval *));
336 const char *inetname __P((struct sockaddr *));
337 void	usage __P((void));
338 
339 int rcvsock;			/* receive (icmp) socket file descriptor */
340 int sndsock;			/* send (udp) socket file descriptor */
341 struct timezone tz;		/* leftover */
342 
343 struct msghdr rcvmhdr;
344 struct iovec rcviov[2];
345 int rcvhlim;
346 struct in6_pktinfo *rcvpktinfo;
347 
348 struct sockaddr_in6 Src, Dst, Rcv;
349 int datalen;			/* How much data */
350 /* XXX: 2064 = 127(max hops in type 0 rthdr) * sizeof(ip6_hdr) + 16(margin) */
351 char rtbuf[2064];
352 #ifdef USE_RFC2292BIS
353 struct ip6_rthdr *rth;
354 #endif
355 struct cmsghdr *cmsg;
356 
357 char *source = 0;
358 char *hostname;
359 
360 int nprobes = 3;
361 int first_hop = 1;
362 int max_hops = 30;
363 u_short ident;
364 u_short port = 32768+666;	/* start udp dest port # for probe packets */
365 int options;			/* socket options */
366 int verbose;
367 int waittime = 5;		/* time to wait for response (in seconds) */
368 int nflag;			/* print addresses numerically */
369 int lflag;			/* print both numerical address & hostname */
370 
371 #ifdef KAME_SCOPEID
372 const int niflag = NI_WITHSCOPEID;
373 #else
374 const int niflag = 0;
375 #endif
376 
377 int
378 main(argc, argv)
379 	int argc;
380 	char *argv[];
381 {
382 	struct hostent *hp;
383 	int error;
384 	struct addrinfo hints, *res;
385 	int ch, i, on, probe, seq, hops, rcvcmsglen;
386 	static u_char *rcvcmsgbuf;
387 	char hbuf[NI_MAXHOST], src0[NI_MAXHOST];
388 
389 	/*
390 	 * Receive ICMP
391 	 */
392 	if ((rcvsock = socket(AF_INET6, SOCK_RAW, IPPROTO_ICMPV6)) < 0) {
393 		perror("socket(ICMPv6)");
394 		exit(5);
395 	}
396 
397 	/* set a minimum set of socket options */
398 	on = 1;
399 	/* specify to tell receiving interface */
400 #ifdef IPV6_RECVPKTINFO
401 	if (setsockopt(rcvsock, IPPROTO_IPV6, IPV6_RECVPKTINFO, &on,
402 		       sizeof(on)) < 0)
403 		err(1, "setsockopt(IPV6_RECVPKTINFO)");
404 #else  /* old adv. API */
405 	if (setsockopt(rcvsock, IPPROTO_IPV6, IPV6_PKTINFO, &on,
406 		       sizeof(on)) < 0)
407 		err(1, "setsockopt(IPV6_PKTINFO)");
408 #endif
409 
410 	/* specify to tell value of hoplimit field of received IP6 hdr */
411 #ifdef IPV6_RECVHOPLIMIT
412 	if (setsockopt(rcvsock, IPPROTO_IPV6, IPV6_RECVHOPLIMIT, &on,
413 		       sizeof(on)) < 0)
414 		err(1, "setsockopt(IPV6_RECVHOPLIMIT)");
415 #else  /* old adv. API */
416 	if (setsockopt(rcvsock, IPPROTO_IPV6, IPV6_HOPLIMIT, &on,
417 		       sizeof(on)) < 0)
418 		err(1, "setsockopt(IPV6_HOPLIMIT)");
419 #endif
420 
421 	/* revoke privs */
422 	seteuid(getuid());
423 	setuid(getuid());
424 
425 	seq = 0;
426 
427 	while ((ch = getopt(argc, argv, "df:g:lm:np:q:rs:w:v")) != EOF)
428 		switch(ch) {
429 		case 'd':
430 			options |= SO_DEBUG;
431 			break;
432 		case 'f':
433 			first_hop = atoi(optarg);
434 			if (first_hop > max_hops) {
435 				Fprintf(stderr,
436 				    "traceroute6: min hoplimit must be <= %d.\n", max_hops);
437 				exit(1);
438 			}
439 			break;
440 		case 'g':
441 			hp = getipnodebyname(optarg, AF_INET6, 0, &h_errno);
442 			if (hp == NULL) {
443 				Fprintf(stderr,
444 				    "traceroute6: unknown host %s\n", optarg);
445 				exit(1);
446 			}
447 #ifdef USE_RFC2292BIS
448 			if (rth == NULL) {
449 				/*
450 				 * XXX: We can't detect the number of
451 				 * intermediate nodes yet.
452 				 */
453 				if ((rth = inet6_rth_init((void *)rtbuf,
454 							 sizeof(rtbuf),
455 							 IPV6_RTHDR_TYPE_0,
456 							 0)) == NULL) {
457 					Fprintf(stderr,
458 						"inet6_rth_init failed.\n");
459 					exit(1);
460 				}
461 			}
462 			if (inet6_rth_add((void *)rth,
463 					  (struct in6_addr *)hp->h_addr)) {
464 				Fprintf(stderr,
465 					"inet6_rth_add failed for %s\n",
466 					optarg);
467 				exit(1);
468 			}
469 #else  /* old advanced API */
470 			if (cmsg == NULL)
471 				cmsg = inet6_rthdr_init(rtbuf, IPV6_RTHDR_TYPE_0);
472 			inet6_rthdr_add(cmsg, (struct in6_addr *)hp->h_addr, IPV6_RTHDR_LOOSE);
473 #endif
474 			freehostent(hp);
475 			break;
476 		case 'l':
477 			lflag++;
478 			break;
479 		case 'm':
480 			max_hops = atoi(optarg);
481 			if (max_hops < first_hop) {
482 				Fprintf(stderr,
483 				    "traceroute6: max hoplimit must be >= %d.\n", first_hop);
484 				exit(1);
485 			}
486 			break;
487 		case 'n':
488 			nflag++;
489 			break;
490 		case 'p':
491 			port = atoi(optarg);
492 			if (port < 1) {
493 				Fprintf(stderr,
494 				    "traceroute6: port must be >0.\n");
495 				exit(1);
496 			}
497 			break;
498 		case 'q':
499 			nprobes = atoi(optarg);
500 			if (nprobes < 1) {
501 				Fprintf(stderr,
502 				    "traceroute6: nprobes must be >0.\n");
503 				exit(1);
504 			}
505 			break;
506 		case 'r':
507 			options |= SO_DONTROUTE;
508 			break;
509 		case 's':
510 			/*
511 			 * set the ip source address of the outbound
512 			 * probe (e.g., on a multi-homed host).
513 			 */
514 			source = optarg;
515 			break;
516 		case 'v':
517 			verbose++;
518 			break;
519 		case 'w':
520 			waittime = atoi(optarg);
521 			if (waittime <= 1) {
522 				Fprintf(stderr,
523 				    "traceroute6: wait must be >1 sec.\n");
524 				exit(1);
525 			}
526 			break;
527 		default:
528 			usage();
529 		}
530 	argc -= optind;
531 	argv += optind;
532 
533 	if (argc < 1)
534 		usage();
535 
536 #if 1
537 	setvbuf(stdout, NULL, _IOLBF, BUFSIZ);
538 #else
539 	setlinebuf (stdout);
540 #endif
541 
542 	memset(&hints, 0, sizeof(hints));
543 	hints.ai_family = PF_INET6;
544 	hints.ai_socktype = SOCK_RAW;
545 	hints.ai_protocol = IPPROTO_ICMPV6;
546 	hints.ai_flags = AI_CANONNAME;
547 	error = getaddrinfo(*argv, NULL, &hints, &res);
548 	if (error) {
549 		(void)fprintf(stderr,
550 			      "traceroute6: %s\n", gai_strerror(error));
551 		exit(1);
552 	}
553 	if (res->ai_addrlen != sizeof(Dst)) {
554 		(void)fprintf(stderr,
555 			      "traceroute6: size of sockaddr mismatch\n");
556 		exit(1);
557 	}
558 	memcpy(&Dst, res->ai_addr, res->ai_addrlen);
559 	hostname = res->ai_canonname ? strdup(res->ai_canonname) : *argv;
560 
561 	if (*++argv)
562 		datalen = atoi(*argv);
563 	if (datalen < 0 || datalen >= MAXPACKET - sizeof(struct opacket)) {
564 		Fprintf(stderr,
565 		    "traceroute6: packet size must be 0 <= s < %ld.\n",
566 		    (long)(MAXPACKET - sizeof(struct opacket)));
567 		exit(1);
568 	}
569 	datalen += sizeof(struct opacket);
570 	outpacket = (struct opacket *)malloc((unsigned)datalen);
571 	if (! outpacket) {
572 		perror("malloc");
573 		exit(1);
574 	}
575 	(void) bzero((char *)outpacket, datalen);
576 
577 	/* initialize msghdr for receiving packets */
578 	rcviov[0].iov_base = (caddr_t)packet;
579 	rcviov[0].iov_len = sizeof(packet);
580 	rcvmhdr.msg_name = (caddr_t)&Rcv;
581 	rcvmhdr.msg_namelen = sizeof(Rcv);
582 	rcvmhdr.msg_iov = rcviov;
583 	rcvmhdr.msg_iovlen = 1;
584 	rcvcmsglen = CMSG_SPACE(sizeof(struct in6_pktinfo))
585 		+ CMSG_SPACE(sizeof(int));
586 	if ((rcvcmsgbuf = malloc(rcvcmsglen)) == NULL) {
587 		Fprintf(stderr, "traceroute6: malloc failed\n");
588 		exit(1);
589 	}
590 	rcvmhdr.msg_control = (caddr_t) rcvcmsgbuf;
591 	rcvmhdr.msg_controllen = rcvcmsglen;
592 
593 	if (options & SO_DEBUG)
594 		(void) setsockopt(rcvsock, SOL_SOCKET, SO_DEBUG,
595 				  (char *)&on, sizeof(on));
596 	if (options & SO_DONTROUTE)
597 		(void) setsockopt(rcvsock, SOL_SOCKET, SO_DONTROUTE,
598 				  (char *)&on, sizeof(on));
599 #ifdef IPSEC
600 #ifdef IPSEC_POLICY_IPSEC
601 	/*
602 	 * do not raise error even if setsockopt fails, kernel may have ipsec
603 	 * turned off.
604 	 */
605 	if (setpolicy(rcvsock, "in bypass") < 0)
606 		errx(1, "%s", ipsec_strerror());
607 	if (setpolicy(rcvsock, "out bypass") < 0)
608 		errx(1, "%s", ipsec_strerror());
609 #else
610     {
611 	int level = IPSEC_LEVEL_NONE;
612 
613 	(void)setsockopt(rcvsock, IPPROTO_IPV6, IPV6_ESP_TRANS_LEVEL, &level,
614 		sizeof(level));
615 	(void)setsockopt(rcvsock, IPPROTO_IPV6, IPV6_ESP_NETWORK_LEVEL, &level,
616 		sizeof(level));
617 #ifdef IP_AUTH_TRANS_LEVEL
618 	(void)setsockopt(rcvsock, IPPROTO_IPV6, IPV6_AUTH_TRANS_LEVEL, &level,
619 		sizeof(level));
620 #else
621 	(void)setsockopt(rcvsock, IPPROTO_IPV6, IPV6_AUTH_LEVEL, &level,
622 		sizeof(level));
623 #endif
624 #ifdef IP_AUTH_NETWORK_LEVEL
625 	(void)setsockopt(rcvsock, IPPROTO_IPV6, IPV6_AUTH_NETWORK_LEVEL, &level,
626 		sizeof(level));
627 #endif
628     }
629 #endif /*IPSEC_POLICY_IPSEC*/
630 #endif /*IPSEC*/
631 
632 	/*
633 	 * Send UDP
634 	 */
635 	if ((sndsock = socket(AF_INET6, SOCK_DGRAM, 0)) < 0) {
636 		perror("socket(SOCK_DGRAM)");
637 		exit(5);
638 	}
639 #ifdef SO_SNDBUF
640 	if (setsockopt(sndsock, SOL_SOCKET, SO_SNDBUF, (char *)&datalen,
641 		       sizeof(datalen)) < 0) {
642 		perror("setsockopt(SO_SNDBUF)");
643 		exit(6);
644 	}
645 #endif /* SO_SNDBUF */
646 	if (options & SO_DEBUG)
647 		(void) setsockopt(sndsock, SOL_SOCKET, SO_DEBUG,
648 				  (char *)&on, sizeof(on));
649 	if (options & SO_DONTROUTE)
650 		(void) setsockopt(sndsock, SOL_SOCKET, SO_DONTROUTE,
651 				  (char *)&on, sizeof(on));
652 #ifdef USE_RFC2292BIS
653 	if (rth) {/* XXX: there is no library to finalize the header... */
654 		rth->ip6r_len = rth->ip6r_segleft * 2;
655 		if (setsockopt(sndsock, IPPROTO_IPV6, IPV6_RTHDR,
656 			       (void *)rth, (rth->ip6r_len + 1) << 3)) {
657 			Fprintf(stderr, "setsockopt(IPV6_RTHDR): %s\n",
658 				strerror(errno));
659 			exit(1);
660 		}
661 	}
662 #else  /* old advanced API */
663 	if (cmsg != NULL) {
664 		inet6_rthdr_lasthop(cmsg, IPV6_RTHDR_LOOSE);
665 		if (setsockopt(sndsock, IPPROTO_IPV6, IPV6_PKTOPTIONS,
666 			       rtbuf, cmsg->cmsg_len) < 0) {
667 			Fprintf(stderr, "setsockopt(IPV6_PKTOPTIONS): %s\n",
668 				strerror(errno));
669 			exit(1);
670 		}
671 	}
672 #endif /* USE_RFC2292BIS */
673 #ifdef IPSEC
674 #ifdef IPSEC_POLICY_IPSEC
675 	/*
676 	 * do not raise error even if setsockopt fails, kernel may have ipsec
677 	 * turned off.
678 	 */
679 	if (setpolicy(sndsock, "in bypass") < 0)
680 		errx(1, "%s", ipsec_strerror());
681 	if (setpolicy(sndsock, "out bypass") < 0)
682 		errx(1, "%s", ipsec_strerror());
683 #else
684     {
685 	int level = IPSEC_LEVEL_BYPASS;
686 
687 	(void)setsockopt(sndsock, IPPROTO_IPV6, IPV6_ESP_TRANS_LEVEL, &level,
688 		sizeof(level));
689 	(void)setsockopt(sndsock, IPPROTO_IPV6, IPV6_ESP_NETWORK_LEVEL, &level,
690 		sizeof(level));
691 #ifdef IP_AUTH_TRANS_LEVEL
692 	(void)setsockopt(sndsock, IPPROTO_IPV6, IPV6_AUTH_TRANS_LEVEL, &level,
693 		sizeof(level));
694 #else
695 	(void)setsockopt(sndsock, IPPROTO_IPV6, IPV6_AUTH_LEVEL, &level,
696 		sizeof(level));
697 #endif
698 #ifdef IP_AUTH_NETWORK_LEVEL
699 	(void)setsockopt(sndsock, IPPROTO_IPV6, IPV6_AUTH_NETWORK_LEVEL, &level,
700 		sizeof(level));
701 #endif
702     }
703 #endif /*IPSEC_POLICY_IPSEC*/
704 #endif /*IPSEC*/
705 
706 	/*
707 	 * Source selection
708 	 */
709 	bzero(&Src, sizeof(Src));
710 	if (source) {
711 		struct addrinfo hints, *res;
712 		int error;
713 
714 		memset(&hints, 0, sizeof(hints));
715 		hints.ai_family = AF_INET6;
716 		hints.ai_socktype = SOCK_DGRAM;	/*dummy*/
717 		hints.ai_flags = AI_NUMERICHOST;
718 		error = getaddrinfo(source, "0", &hints, &res);
719 		if (error) {
720 			Printf("traceroute6: %s: %s\n", source,
721 			    gai_strerror(error));
722 			exit(1);
723 		}
724 		if (res->ai_addrlen > sizeof(Src)) {
725 			Printf("traceroute6: %s: %s\n", source,
726 			    gai_strerror(error));
727 			exit(1);
728 		}
729 		memcpy(&Src, res->ai_addr, res->ai_addrlen);
730 		freeaddrinfo(res);
731 	} else {
732 		struct sockaddr_in6 Nxt;
733 		int dummy, len;
734 
735 		Nxt = Dst;
736 		Nxt.sin6_port = htons(DUMMY_PORT);
737 		if (cmsg != NULL)
738 			bcopy(inet6_rthdr_getaddr(cmsg, 1), &Nxt.sin6_addr,
739 			      sizeof(Nxt.sin6_addr));
740 		if ((dummy = socket(AF_INET6, SOCK_DGRAM, 0)) < 0) {
741 			perror("socket");
742 			exit(1);
743 		}
744 		if (connect(dummy, (struct sockaddr *)&Nxt, Nxt.sin6_len) < 0) {
745 			perror("connect");
746 			exit(1);
747 		}
748 		len = sizeof(Src);
749 		if (getsockname(dummy, (struct sockaddr *)&Src, &len) < 0) {
750 			perror("getsockname");
751 			exit(1);
752 		}
753 		if (getnameinfo((struct sockaddr *)&Src, Src.sin6_len,
754 				src0, sizeof(src0), NULL, 0,
755 				NI_NUMERICHOST | niflag)) {
756 			Fprintf(stderr, "getnameinfo failed for source\n");
757 			exit(1);
758 		}
759 		source = src0;
760 		close(dummy);
761 	}
762 
763 #if 1
764 	ident = (getpid() & 0xffff) | 0x8000;
765 #else
766 	ident = 0;	/*let the kernel pick one*/
767 #endif
768 	Src.sin6_port = htons(ident);
769 	if (bind(sndsock, (struct sockaddr *)&Src, Src.sin6_len) < 0) {
770 		perror("bind");
771 		exit(1);
772 	}
773 
774 	if (ident == 0) {
775 		int len;
776 
777 		len = sizeof(Src);
778 		if (getsockname(sndsock, (struct sockaddr *)&Src, &i) < 0) {
779 			perror("getsockname");
780 			exit(1);
781 		}
782 		ident = ntohs(Src.sin6_port);
783 	}
784 
785 	/*
786 	 * Message to users
787 	 */
788 	if (getnameinfo((struct sockaddr *)&Dst, Dst.sin6_len, hbuf,
789 			sizeof(hbuf), NULL, 0, NI_NUMERICHOST | niflag))
790 		strcpy(hbuf, "(invalid)");
791 	Fprintf(stderr, "traceroute6");
792 	Fprintf(stderr, " to %s (%s)", hostname, hbuf);
793 	if (source)
794 		Fprintf(stderr, " from %s", source);
795 	Fprintf(stderr,
796 		", %d hops max, %d byte packets\n",
797 		max_hops, datalen);
798 	(void) fflush(stderr);
799 
800 	if (first_hop > 1)
801 		Printf("Skipping %d intermediate hops\n", first_hop - 1);
802 
803 	/*
804 	 * Main loop
805 	 */
806 	for (hops = first_hop; hops <= max_hops; ++hops) {
807 		struct in6_addr lastaddr;
808 		int got_there = 0;
809 		int unreachable = 0;
810 
811 		Printf("%2d ", hops);
812 		bzero(&lastaddr, sizeof(lastaddr));
813 		for (probe = 0; probe < nprobes; ++probe) {
814 			int cc;
815 			struct timeval t1, t2;
816 			struct timezone tz;
817 
818 			(void) gettimeofday(&t1, &tz);
819 			send_probe(++seq, hops);
820 			while ((cc = wait_for_reply(rcvsock, &rcvmhdr))) {
821 				(void) gettimeofday(&t2, &tz);
822 				if ((i = packet_ok(&rcvmhdr, cc, seq))) {
823 					if (! IN6_ARE_ADDR_EQUAL(&Rcv.sin6_addr,
824 							    &lastaddr)) {
825 						print(&rcvmhdr, cc);
826 						lastaddr = Rcv.sin6_addr;
827 					}
828 					Printf("  %g ms", deltaT(&t1, &t2));
829 					switch(i - 1) {
830 					case ICMP6_DST_UNREACH_NOROUTE:
831 						++unreachable;
832 						Printf(" !N");
833 						break;
834 					case ICMP6_DST_UNREACH_ADMIN:
835 						++unreachable;
836 						Printf(" !P");
837 						break;
838 					case ICMP6_DST_UNREACH_NOTNEIGHBOR:
839 						++unreachable;
840 						Printf(" !S");
841 						break;
842 					case ICMP6_DST_UNREACH_ADDR:
843 						++unreachable;
844 						Printf(" !A");
845 						break;
846 					case ICMP6_DST_UNREACH_NOPORT:
847 						if (rcvhlim >= 0 &&
848 						    rcvhlim <= 1)
849 							Printf(" !");
850 						++got_there;
851 						break;
852 					}
853 					break;
854 				}
855 			}
856 			if (cc == 0)
857 				Printf(" *");
858 			(void) fflush(stdout);
859 		}
860 		putchar('\n');
861 		if (got_there ||
862 		    (unreachable > 0 && unreachable >= ((nprobes + 1) / 2))) {
863 			exit(0);
864 		}
865 	}
866 
867 	exit(0);
868 }
869 
870 int
871 wait_for_reply(sock, mhdr)
872 	int sock;
873 	struct msghdr *mhdr;
874 {
875 #ifdef HAVE_POLL
876 	struct pollfd pfd[1];
877 	int cc = 0;
878 
879 	pfd[0].fd = sock;
880 	pfd[0].events = POLLIN;
881 	pfd[0].revents = 0;
882 
883 	if (poll(pfd, 1, waittime * 1000) > 0)
884 		cc = recvmsg(rcvsock, mhdr, 0);
885 
886 	return(cc);
887 #else
888 	fd_set *fdsp;
889 	struct timeval wait;
890 	int cc = 0, fdsn;
891 
892 	fdsn = howmany(sock+1, NFDBITS) * sizeof(fd_mask);
893 	if ((fdsp = (fd_set *)malloc(fdsn)) == NULL)
894 		err(1, "malloc");
895 	memset(fdsp, 0, fdsn);
896 	FD_SET(sock, fdsp);
897 	wait.tv_sec = waittime; wait.tv_usec = 0;
898 
899 	if (select(sock+1, fdsp, (fd_set *)0, (fd_set *)0, &wait) > 0)
900 		cc = recvmsg(rcvsock, mhdr, 0);
901 
902 	free(fdsp);
903 	return(cc);
904 #endif
905 }
906 
907 #ifdef IPSEC
908 #ifdef IPSEC_POLICY_IPSEC
909 int
910 setpolicy(so, policy)
911 	int so;
912 	char *policy;
913 {
914 	char *buf;
915 
916 	buf = ipsec_set_policy(policy, strlen(policy));
917 	if (buf == NULL) {
918 		warnx("%s", ipsec_strerror());
919 		return -1;
920 	}
921 	(void)setsockopt(so, IPPROTO_IPV6, IPV6_IPSEC_POLICY,
922 		buf, ipsec_get_policylen(buf));
923 
924 	free(buf);
925 
926 	return 0;
927 }
928 #endif
929 #endif
930 
931 void
932 send_probe(seq, hops)
933 	int seq, hops;
934 {
935 	struct opacket *op = outpacket;
936 	int i;
937 
938 	if(setsockopt(sndsock, IPPROTO_IPV6, IPV6_UNICAST_HOPS,
939 		      (char *)&hops, sizeof(hops)) < 0) {
940 		perror("setsockopt IPV6_UNICAST_HOPS");
941 	}
942 
943 	Dst.sin6_port = htons(port + seq);
944 
945 	op->seq = seq;
946 	op->hops = hops;
947 	(void) gettimeofday(&op->tv, &tz);
948 
949 	i = sendto(sndsock, (char *)outpacket, datalen , 0,
950 		   (struct sockaddr *)&Dst, Dst.sin6_len);
951 	if (i < 0 || i != datalen)  {
952 		if (i<0)
953 			perror("sendto");
954 		Printf("traceroute6: wrote %s %d chars, ret=%d\n", hostname,
955 		       datalen, i);
956 		(void) fflush(stdout);
957 	}
958 }
959 
960 int
961 get_hoplim(mhdr)
962 	struct msghdr *mhdr;
963 {
964 	struct cmsghdr *cm;
965 
966 	for (cm = (struct cmsghdr *)CMSG_FIRSTHDR(mhdr); cm;
967 	     cm = (struct cmsghdr *)CMSG_NXTHDR(mhdr, cm)) {
968 		if (cm->cmsg_level == IPPROTO_IPV6 &&
969 		    cm->cmsg_type == IPV6_HOPLIMIT &&
970 		    cm->cmsg_len == CMSG_LEN(sizeof(int)))
971 			return(*(int *)CMSG_DATA(cm));
972 	}
973 
974 	return(-1);
975 }
976 
977 double
978 deltaT(t1p, t2p)
979 	struct timeval *t1p, *t2p;
980 {
981 	register double dt;
982 
983 	dt = (double)(t2p->tv_sec - t1p->tv_sec) * 1000.0 +
984 	     (double)(t2p->tv_usec - t1p->tv_usec) / 1000.0;
985 	return (dt);
986 }
987 
988 
989 /*
990  * Convert an ICMP "type" field to a printable string.
991  */
992 char *
993 pr_type(t0)
994 	int t0;
995 {
996 	u_char t = t0 & 0xff;
997 	char *cp;
998 
999 	switch (t) {
1000 	case ICMP6_DST_UNREACH:
1001 		cp = "Destination Unreachable";
1002 		break;
1003 	case ICMP6_PACKET_TOO_BIG:
1004 		cp = "Pakcet Too Big";
1005 		break;
1006 	case ICMP6_TIME_EXCEEDED:
1007 		cp = "Time Exceeded";
1008 		break;
1009 	case ICMP6_PARAM_PROB:
1010 		cp = "Parameter Problem";
1011 		break;
1012 	case ICMP6_ECHO_REQUEST:
1013 		cp = "Echo Request";
1014 		break;
1015 	case ICMP6_ECHO_REPLY:
1016 		cp = "Echo Reply";
1017 		break;
1018 	case ICMP6_MEMBERSHIP_QUERY:
1019 		cp = "Group Membership Query";
1020 		break;
1021 	case ICMP6_MEMBERSHIP_REPORT:
1022 		cp = "Group Membership Report";
1023 		break;
1024 	case ICMP6_MEMBERSHIP_REDUCTION:
1025 		cp = "Group Membership Reduction";
1026 		break;
1027 	case ND_ROUTER_SOLICIT:
1028 		cp = "Router Solicitation";
1029 		break;
1030 	case ND_ROUTER_ADVERT:
1031 		cp = "Router Advertisement";
1032 		break;
1033 	case ND_NEIGHBOR_SOLICIT:
1034 		cp = "Neighbor Solicitation";
1035 		break;
1036 	case ND_NEIGHBOR_ADVERT:
1037 		cp = "Neighbor Advertisement";
1038 		break;
1039 	case ND_REDIRECT:
1040 		cp = "Redirect";
1041 		break;
1042 	default:
1043 		cp = "Unknown";
1044 		break;
1045 	}
1046 	return cp;
1047 }
1048 
1049 
1050 int
1051 packet_ok(mhdr, cc, seq)
1052 	struct msghdr *mhdr;
1053 	int cc;
1054 	int seq;
1055 {
1056 	register struct icmp6_hdr *icp;
1057 	struct sockaddr_in6 *from = (struct sockaddr_in6 *)mhdr->msg_name;
1058 	u_char type, code;
1059 	char *buf = (char *)mhdr->msg_iov[0].iov_base;
1060 	struct cmsghdr *cm;
1061 	int *hlimp;
1062 	char hbuf[NI_MAXHOST];
1063 
1064 #ifdef OLDRAWSOCKET
1065 	int hlen;
1066 	struct ip6_hdr *ip;
1067 #endif
1068 
1069 #ifdef OLDRAWSOCKET
1070 	ip = (struct ip6_hdr *) buf;
1071 	hlen = sizeof(struct ip6_hdr);
1072 	if (cc < hlen + sizeof(struct icmp6_hdr)) {
1073 		if (verbose) {
1074 			if (getnameinfo((struct sockaddr *)from, from->sin6_len,
1075 			    hbuf, sizeof(hbuf), NULL, 0,
1076 			    NI_NUMERICHOST | niflag) != 0)
1077 				strcpy(hbuf, "invalid");
1078 			Printf("packet too short (%d bytes) from %s\n", cc,
1079 			    hbuf);
1080 		}
1081 		return (0);
1082 	}
1083 	cc -= hlen;
1084 	icp = (struct icmp6_hdr *)(buf + hlen);
1085 #else
1086 	if (cc < sizeof(struct icmp6_hdr)) {
1087 		if (verbose) {
1088 			if (getnameinfo((struct sockaddr *)from, from->sin6_len,
1089 			    hbuf, sizeof(hbuf), NULL, 0,
1090 			    NI_NUMERICHOST | niflag) != 0)
1091 				strcpy(hbuf, "invalid");
1092 			Printf("data too short (%d bytes) from %s\n", cc, hbuf);
1093 		}
1094 		return(0);
1095 	}
1096 	icp = (struct icmp6_hdr *)buf;
1097 #endif
1098 	/* get optional information via advanced API */
1099 	rcvpktinfo = NULL;
1100 	hlimp = NULL;
1101 	for (cm = (struct cmsghdr *)CMSG_FIRSTHDR(mhdr); cm;
1102 	     cm = (struct cmsghdr *)CMSG_NXTHDR(mhdr, cm)) {
1103 		if (cm->cmsg_level == IPPROTO_IPV6 &&
1104 		    cm->cmsg_type == IPV6_PKTINFO &&
1105 		    cm->cmsg_len ==
1106 		    CMSG_LEN(sizeof(struct in6_pktinfo)))
1107 			rcvpktinfo = (struct in6_pktinfo *)(CMSG_DATA(cm));
1108 
1109 		if (cm->cmsg_level == IPPROTO_IPV6 &&
1110 		    cm->cmsg_type == IPV6_HOPLIMIT &&
1111 		    cm->cmsg_len == CMSG_LEN(sizeof(int)))
1112 			hlimp = (int *)CMSG_DATA(cm);
1113 	}
1114 	if (rcvpktinfo == NULL || hlimp == NULL) {
1115 		warnx("failed to get received hop limit or packet info");
1116 #if 0
1117 		return(0);
1118 #else
1119 		rcvhlim = 0;	/*XXX*/
1120 #endif
1121 	}
1122 	else
1123 		rcvhlim = *hlimp;
1124 
1125 	type = icp->icmp6_type;
1126 	code = icp->icmp6_code;
1127 	if ((type == ICMP6_TIME_EXCEEDED && code == ICMP6_TIME_EXCEED_TRANSIT)
1128 	 || type == ICMP6_DST_UNREACH) {
1129 		struct ip6_hdr *hip;
1130 		struct udphdr *up;
1131 
1132 		hip = (struct ip6_hdr *)(icp + 1);
1133 		if ((up = get_udphdr(hip, (u_char *)(buf + cc))) == NULL) {
1134 			if (verbose)
1135 				warnx("failed to get upper layer header");
1136 			return(0);
1137 		}
1138 		if (up->uh_sport == htons(ident) &&
1139 		    up->uh_dport == htons(port+seq))
1140 			return (type == ICMP6_TIME_EXCEEDED ? -1 : code + 1);
1141 	}
1142 	if (verbose) {
1143 		int i;
1144 		u_int8_t *p;
1145 		char sbuf[NI_MAXHOST+1], dbuf[INET6_ADDRSTRLEN];
1146 
1147 		if (getnameinfo((struct sockaddr *)from, from->sin6_len,
1148 		    sbuf, sizeof(sbuf), NULL, 0, NI_NUMERICHOST | niflag) != 0)
1149 			strcpy(sbuf, "invalid");
1150 		Printf("\n%d bytes from %s to %s", cc, sbuf,
1151 		    rcvpktinfo ? inet_ntop(AF_INET6, &rcvpktinfo->ipi6_addr,
1152 					dbuf, sizeof(dbuf))
1153 			       : "?");
1154 		Printf(": icmp type %d (%s) code %d\n", type, pr_type(type),
1155 		       icp->icmp6_code);
1156 		p = (u_int8_t *)(icp + 1);
1157 #define WIDTH	16
1158 		for (i = 0; i < cc; i++) {
1159 			if (i % WIDTH == 0)
1160 				Printf("%04x:", i);
1161 			if (i % 4 == 0)
1162 				Printf(" ");
1163 			Printf("%02x", p[i]);
1164 			if (i % WIDTH == WIDTH - 1)
1165 				Printf("\n");
1166 		}
1167 		if (cc % WIDTH != 0)
1168 			Printf("\n");
1169 	}
1170 	return(0);
1171 }
1172 
1173 /*
1174  * Increment pointer until find the UDP header.
1175  */
1176 struct udphdr *
1177 get_udphdr(ip6, lim)
1178 	struct ip6_hdr *ip6;
1179 	u_char *lim;
1180 {
1181 	u_char *cp = (u_char *)ip6, nh;
1182 	int hlen;
1183 
1184 	if (cp + sizeof(*ip6) >= lim)
1185 		return(NULL);
1186 
1187 	nh = ip6->ip6_nxt;
1188 	cp += sizeof(struct ip6_hdr);
1189 
1190 	while(lim - cp >= 8) {
1191 		switch(nh) {
1192 		 case IPPROTO_ESP:
1193 		 case IPPROTO_TCP:
1194 		 case IPPROTO_ICMPV6:
1195 			 return(NULL);
1196 		 case IPPROTO_UDP:
1197 			 return((struct udphdr *)cp);
1198 		 case IPPROTO_FRAGMENT:
1199 			 hlen = sizeof(struct ip6_frag);
1200 			 nh = ((struct ip6_frag *)cp)->ip6f_nxt;
1201 			 break;
1202 		 case IPPROTO_AH:
1203 			 hlen = (((struct ip6_ext *)cp)->ip6e_len + 2) << 2;
1204 			 nh = ((struct ip6_ext *)cp)->ip6e_nxt;
1205 			 break;
1206 		  default:
1207 			  hlen = (((struct ip6_ext *)cp)->ip6e_len + 1) << 3;
1208 			  nh = ((struct ip6_ext *)cp)->ip6e_nxt;
1209 			  break;
1210 		}
1211 
1212 		cp += hlen;
1213 	}
1214 
1215 	return(NULL);
1216 }
1217 
1218 void
1219 print(mhdr, cc)
1220 	struct msghdr *mhdr;
1221 	int cc;
1222 {
1223 	struct sockaddr_in6 *from = (struct sockaddr_in6 *)mhdr->msg_name;
1224 	char hbuf[NI_MAXHOST];
1225 
1226 	if (getnameinfo((struct sockaddr *)from, from->sin6_len,
1227 	    hbuf, sizeof(hbuf), NULL, 0, NI_NUMERICHOST | niflag) != 0)
1228 		strcpy(hbuf, "invalid");
1229 	if (nflag)
1230 		Printf(" %s", hbuf);
1231 	else if (lflag)
1232 		Printf(" %s (%s)", inetname((struct sockaddr *)from), hbuf);
1233 	else
1234 		Printf(" %s", inetname((struct sockaddr *)from));
1235 
1236 	if (verbose) {
1237 #ifdef OLDRAWSOCKET
1238 		Printf(" %d bytes to %s", cc,
1239 		    rcvpktinfo ? inet_ntop(AF_INET6, &rcvpktinfo->ipi6_addr,
1240 					hbuf, sizeof(hbuf))
1241 			       : "?");
1242 #else
1243 		Printf(" %d bytes of data to %s", cc,
1244 		    rcvpktinfo ?  inet_ntop(AF_INET6, &rcvpktinfo->ipi6_addr,
1245 					hbuf, sizeof(hbuf))
1246 			       : "?");
1247 #endif
1248 	}
1249 }
1250 
1251 /*
1252  * Subtract 2 timeval structs:  out = out - in.
1253  * Out is assumed to be >= in.
1254  */
1255 void
1256 tvsub(out, in)
1257 	register struct timeval *out, *in;
1258 {
1259 	if ((out->tv_usec -= in->tv_usec) < 0)   {
1260 		out->tv_sec--;
1261 		out->tv_usec += 1000000;
1262 	}
1263 	out->tv_sec -= in->tv_sec;
1264 }
1265 
1266 
1267 /*
1268  * Construct an Internet address representation.
1269  * If the nflag has been supplied, give
1270  * numeric value, otherwise try for symbolic name.
1271  */
1272 const char *
1273 inetname(sa)
1274 	struct sockaddr *sa;
1275 {
1276 	register char *cp;
1277 	static char line[NI_MAXHOST];
1278 	static char domain[MAXHOSTNAMELEN + 1];
1279 	static int first = 1;
1280 
1281 	if (first && !nflag) {
1282 		first = 0;
1283 		if (gethostname(domain, MAXHOSTNAMELEN) == 0 &&
1284 		    (cp = index(domain, '.')))
1285 			(void) strcpy(domain, cp + 1);
1286 		else
1287 			domain[0] = 0;
1288 	}
1289 	cp = NULL;
1290 	if (!nflag) {
1291 		if (getnameinfo(sa, sa->sa_len, line, sizeof(line), NULL, 0,
1292 		    NI_NAMEREQD) == 0) {
1293 			if ((cp = index(line, '.')) &&
1294 			    !strcmp(cp + 1, domain))
1295 				*cp = 0;
1296 			cp = line;
1297 		}
1298 	}
1299 	if (cp)
1300 		return cp;
1301 
1302 	if (getnameinfo(sa, sa->sa_len, line, sizeof(line), NULL, 0,
1303 	    NI_NUMERICHOST | niflag) != 0)
1304 		strcpy(line, "invalid");
1305 	return line;
1306 }
1307 
1308 void
1309 usage()
1310 {
1311 	(void)fprintf(stderr,
1312 "usage: traceroute6 [-dlnrv] [-f first_hop] [-m max_hops] [-p port#] \n"
1313 "       [-q nqueries] [-s src_addr] [-g gateway] [-w wait] host [data size]\n");
1314 	exit(1);
1315 }
1316