xref: /freebsd/usr.sbin/traceroute6/traceroute6.c (revision 1e413cf93298b5b97441a21d9a50fdcd0ee9945e)
1 /*	$KAME: traceroute6.c,v 1.68 2004/01/25 11:16:12 suz 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 an 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 #include <sys/sysctl.h>
260 
261 #include <netinet/in.h>
262 
263 #include <arpa/inet.h>
264 
265 #include <netdb.h>
266 #include <stdio.h>
267 #include <err.h>
268 #ifdef HAVE_POLL
269 #include <poll.h>
270 #endif
271 #include <errno.h>
272 #include <stdlib.h>
273 #include <string.h>
274 #include <unistd.h>
275 
276 #include <netinet/ip6.h>
277 #include <netinet/icmp6.h>
278 #include <netinet/udp.h>
279 
280 #ifdef IPSEC
281 #include <net/route.h>
282 #include <netipsec/ipsec.h>
283 #endif
284 
285 #define DUMMY_PORT 10010
286 
287 #define	MAXPACKET	65535	/* max ip packet size */
288 
289 #ifndef HAVE_GETIPNODEBYNAME
290 #define getipnodebyname(x, y, z, u)	gethostbyname2((x), (y))
291 #define freehostent(x)
292 #endif
293 
294 /*
295  * format of a (udp) probe packet.
296  */
297 struct tv32 {
298 	u_int32_t tv32_sec;
299 	u_int32_t tv32_usec;
300 };
301 
302 struct opacket {
303 	u_char seq;		/* sequence number of this packet */
304 	u_char hops;		/* hop limit of the packet */
305 	u_char pad[2];
306 	struct tv32 tv;		/* time packet left */
307 } __attribute__((__packed__));
308 
309 u_char	packet[512];		/* last inbound (icmp) packet */
310 struct opacket	*outpacket;	/* last output (udp) packet */
311 
312 int	main(int, char *[]);
313 int	wait_for_reply(int, struct msghdr *);
314 #ifdef IPSEC
315 #ifdef IPSEC_POLICY_IPSEC
316 int	setpolicy(int so, char *policy);
317 #endif
318 #endif
319 void	send_probe(int, u_long);
320 struct udphdr *get_udphdr(struct ip6_hdr *, u_char *);
321 int	get_hoplim(struct msghdr *);
322 double	deltaT(struct timeval *, struct timeval *);
323 char	*pr_type(int);
324 int	packet_ok(struct msghdr *, int, int);
325 void	print(struct msghdr *, int);
326 const char *inetname(struct sockaddr *);
327 void	usage(void);
328 
329 int rcvsock;			/* receive (icmp) socket file descriptor */
330 int sndsock;			/* send (udp) socket file descriptor */
331 
332 struct msghdr rcvmhdr;
333 struct iovec rcviov[2];
334 int rcvhlim;
335 struct in6_pktinfo *rcvpktinfo;
336 
337 struct sockaddr_in6 Src, Dst, Rcv;
338 u_long datalen;			/* How much data */
339 #define	ICMP6ECHOLEN	8
340 /* XXX: 2064 = 127(max hops in type 0 rthdr) * sizeof(ip6_hdr) + 16(margin) */
341 char rtbuf[2064];
342 #ifdef USE_RFC2292BIS
343 struct ip6_rthdr *rth;
344 #endif
345 struct cmsghdr *cmsg;
346 
347 char *source = 0;
348 char *hostname;
349 
350 u_long nprobes = 3;
351 u_long first_hop = 1;
352 u_long max_hops = 30;
353 u_int16_t srcport;
354 u_int16_t port = 32768+666;	/* start udp dest port # for probe packets */
355 u_int16_t ident;
356 int options;			/* socket options */
357 int verbose;
358 int waittime = 5;		/* time to wait for response (in seconds) */
359 int nflag;			/* print addresses numerically */
360 int useicmp;
361 int lflag;			/* print both numerical address & hostname */
362 
363 int
364 main(argc, argv)
365 	int argc;
366 	char *argv[];
367 {
368 	int mib[4] = { CTL_NET, PF_INET6, IPPROTO_IPV6, IPV6CTL_DEFHLIM };
369 	char hbuf[NI_MAXHOST], src0[NI_MAXHOST], *ep;
370 	int ch, i, on = 1, seq, rcvcmsglen, error, minlen;
371 	struct addrinfo hints, *res;
372 	static u_char *rcvcmsgbuf;
373 	u_long probe, hops, lport;
374 	struct hostent *hp;
375 	size_t size;
376 	uid_t uid;
377 
378 	/*
379 	 * Receive ICMP
380 	 */
381 	if ((rcvsock = socket(AF_INET6, SOCK_RAW, IPPROTO_ICMPV6)) < 0) {
382 		perror("socket(ICMPv6)");
383 		exit(5);
384 	}
385 
386 	/* revoke privs */
387 	uid = getuid();
388 	if (setresuid(uid, uid, uid) == -1) {
389 		perror("setresuid");
390 		exit(1);
391 	}
392 
393 	size = sizeof(i);
394 	(void) sysctl(mib, sizeof(mib)/sizeof(mib[0]), &i, &size, NULL, 0);
395 	max_hops = i;
396 
397 	/* specify to tell receiving interface */
398 #ifdef IPV6_RECVPKTINFO
399 	if (setsockopt(rcvsock, IPPROTO_IPV6, IPV6_RECVPKTINFO, &on,
400 	    sizeof(on)) < 0)
401 		err(1, "setsockopt(IPV6_RECVPKTINFO)");
402 #else  /* old adv. API */
403 	if (setsockopt(rcvsock, IPPROTO_IPV6, IPV6_PKTINFO, &on,
404 	    sizeof(on)) < 0)
405 		err(1, "setsockopt(IPV6_PKTINFO)");
406 #endif
407 
408 	/* specify to tell value of hoplimit field of received IP6 hdr */
409 #ifdef IPV6_RECVHOPLIMIT
410 	if (setsockopt(rcvsock, IPPROTO_IPV6, IPV6_RECVHOPLIMIT, &on,
411 	    sizeof(on)) < 0)
412 		err(1, "setsockopt(IPV6_RECVHOPLIMIT)");
413 #else  /* old adv. API */
414 	if (setsockopt(rcvsock, IPPROTO_IPV6, IPV6_HOPLIMIT, &on,
415 	    sizeof(on)) < 0)
416 		err(1, "setsockopt(IPV6_HOPLIMIT)");
417 #endif
418 
419 	seq = 0;
420 
421 	while ((ch = getopt(argc, argv, "df:g:Ilm:np:q:rs:w:v")) != -1)
422 		switch (ch) {
423 		case 'd':
424 			options |= SO_DEBUG;
425 			break;
426 		case 'f':
427 			ep = NULL;
428 			errno = 0;
429 			first_hop = strtoul(optarg, &ep, 0);
430 			if (errno || !*optarg || *ep || first_hop > 255) {
431 				fprintf(stderr,
432 				    "traceroute6: invalid min hoplimit.\n");
433 				exit(1);
434 			}
435 			break;
436 		case 'g':
437 			hp = getipnodebyname(optarg, AF_INET6, 0, &h_errno);
438 			if (hp == NULL) {
439 				fprintf(stderr,
440 				    "traceroute6: unknown host %s\n", optarg);
441 				exit(1);
442 			}
443 #ifdef USE_RFC2292BIS
444 			if (rth == NULL) {
445 				/*
446 				 * XXX: We can't detect the number of
447 				 * intermediate nodes yet.
448 				 */
449 				if ((rth = inet6_rth_init((void *)rtbuf,
450 				    sizeof(rtbuf), IPV6_RTHDR_TYPE_0,
451 				    0)) == NULL) {
452 					fprintf(stderr,
453 					    "inet6_rth_init failed.\n");
454 					exit(1);
455 				}
456 			}
457 			if (inet6_rth_add((void *)rth,
458 			    (struct in6_addr *)hp->h_addr)) {
459 				fprintf(stderr,
460 				    "inet6_rth_add failed for %s\n",
461 				    optarg);
462 				exit(1);
463 			}
464 #else  /* old advanced API */
465 			if (cmsg == NULL)
466 				cmsg = inet6_rthdr_init(rtbuf, IPV6_RTHDR_TYPE_0);
467 			inet6_rthdr_add(cmsg, (struct in6_addr *)hp->h_addr,
468 			    IPV6_RTHDR_LOOSE);
469 #endif
470 			freehostent(hp);
471 			break;
472 		case 'I':
473 			useicmp++;
474 			ident = htons(getpid() & 0xffff); /* same as ping6 */
475 			break;
476 		case 'l':
477 			lflag++;
478 			break;
479 		case 'm':
480 			ep = NULL;
481 			errno = 0;
482 			max_hops = strtoul(optarg, &ep, 0);
483 			if (errno || !*optarg || *ep || max_hops > 255) {
484 				fprintf(stderr,
485 				    "traceroute6: invalid max hoplimit.\n");
486 				exit(1);
487 			}
488 			break;
489 		case 'n':
490 			nflag++;
491 			break;
492 		case 'p':
493 			ep = NULL;
494 			errno = 0;
495 			lport = strtoul(optarg, &ep, 0);
496 			if (errno || !*optarg || *ep) {
497 				fprintf(stderr, "traceroute6: invalid port.\n");
498 				exit(1);
499 			}
500 			if (lport == 0 || lport != (lport & 0xffff)) {
501 				fprintf(stderr,
502 				    "traceroute6: port out of range.\n");
503 				exit(1);
504 			}
505 			port = lport & 0xffff;
506 			break;
507 		case 'q':
508 			ep = NULL;
509 			errno = 0;
510 			nprobes = strtoul(optarg, &ep, 0);
511 			if (errno || !*optarg || *ep) {
512 				fprintf(stderr,
513 				    "traceroute6: invalid nprobes.\n");
514 				exit(1);
515 			}
516 			if (nprobes < 1) {
517 				fprintf(stderr,
518 				    "traceroute6: nprobes must be >0.\n");
519 				exit(1);
520 			}
521 			break;
522 		case 'r':
523 			options |= SO_DONTROUTE;
524 			break;
525 		case 's':
526 			/*
527 			 * set the ip source address of the outbound
528 			 * probe (e.g., on a multi-homed host).
529 			 */
530 			source = optarg;
531 			break;
532 		case 'v':
533 			verbose++;
534 			break;
535 		case 'w':
536 			ep = NULL;
537 			errno = 0;
538 			waittime = strtoul(optarg, &ep, 0);
539 			if (errno || !*optarg || *ep) {
540 				fprintf(stderr,
541 				    "traceroute6: invalid wait time.\n");
542 				exit(1);
543 			}
544 			if (waittime < 1) {
545 				fprintf(stderr,
546 				    "traceroute6: wait must be >= 1 sec.\n");
547 				exit(1);
548 			}
549 			break;
550 		default:
551 			usage();
552 		}
553 	argc -= optind;
554 	argv += optind;
555 
556 	if (max_hops < first_hop) {
557 		fprintf(stderr,
558 		    "traceroute6: max hoplimit must be larger than first hoplimit.\n");
559 		exit(1);
560 	}
561 
562 	if (argc < 1 || argc > 2)
563 		usage();
564 
565 #if 1
566 	setvbuf(stdout, NULL, _IOLBF, BUFSIZ);
567 #else
568 	setlinebuf(stdout);
569 #endif
570 
571 	memset(&hints, 0, sizeof(hints));
572 	hints.ai_family = PF_INET6;
573 	hints.ai_socktype = SOCK_RAW;
574 	hints.ai_protocol = IPPROTO_ICMPV6;
575 	hints.ai_flags = AI_CANONNAME;
576 	error = getaddrinfo(*argv, NULL, &hints, &res);
577 	if (error) {
578 		fprintf(stderr,
579 		    "traceroute6: %s\n", gai_strerror(error));
580 		exit(1);
581 	}
582 	if (res->ai_addrlen != sizeof(Dst)) {
583 		fprintf(stderr,
584 		    "traceroute6: size of sockaddr mismatch\n");
585 		exit(1);
586 	}
587 	memcpy(&Dst, res->ai_addr, res->ai_addrlen);
588 	hostname = res->ai_canonname ? strdup(res->ai_canonname) : *argv;
589 	if (!hostname) {
590 		fprintf(stderr, "traceroute6: not enough core\n");
591 		exit(1);
592 	}
593 	if (res->ai_next) {
594 		if (getnameinfo(res->ai_addr, res->ai_addrlen, hbuf,
595 		    sizeof(hbuf), NULL, 0, NI_NUMERICHOST) != 0)
596 			strlcpy(hbuf, "?", sizeof(hbuf));
597 		fprintf(stderr, "traceroute6: Warning: %s has multiple "
598 		    "addresses; using %s\n", hostname, hbuf);
599 	}
600 
601 	if (*++argv) {
602 		ep = NULL;
603 		errno = 0;
604 		datalen = strtoul(*argv, &ep, 0);
605 		if (errno || !*argv || *ep) {
606 			fprintf(stderr,
607 			    "traceroute6: invalid packet length.\n");
608 			exit(1);
609 		}
610 	}
611 	if (useicmp)
612 		minlen = ICMP6ECHOLEN + sizeof(struct tv32);
613 	else
614 		minlen = sizeof(struct opacket);
615 	if (datalen < minlen)
616 		datalen = minlen;
617 	else if (datalen >= MAXPACKET) {
618 		fprintf(stderr,
619 		    "traceroute6: packet size must be %d <= s < %ld.\n",
620 		    minlen, (long)MAXPACKET);
621 		exit(1);
622 	}
623 	outpacket = (struct opacket *)malloc((unsigned)datalen);
624 	if (!outpacket) {
625 		perror("malloc");
626 		exit(1);
627 	}
628 	(void) bzero((char *)outpacket, datalen);
629 
630 	/* initialize msghdr for receiving packets */
631 	rcviov[0].iov_base = (caddr_t)packet;
632 	rcviov[0].iov_len = sizeof(packet);
633 	rcvmhdr.msg_name = (caddr_t)&Rcv;
634 	rcvmhdr.msg_namelen = sizeof(Rcv);
635 	rcvmhdr.msg_iov = rcviov;
636 	rcvmhdr.msg_iovlen = 1;
637 	rcvcmsglen = CMSG_SPACE(sizeof(struct in6_pktinfo)) +
638 	    CMSG_SPACE(sizeof(int));
639 	if ((rcvcmsgbuf = malloc(rcvcmsglen)) == NULL) {
640 		fprintf(stderr, "traceroute6: malloc failed\n");
641 		exit(1);
642 	}
643 	rcvmhdr.msg_control = (caddr_t) rcvcmsgbuf;
644 	rcvmhdr.msg_controllen = rcvcmsglen;
645 
646 	if (options & SO_DEBUG)
647 		(void) setsockopt(rcvsock, SOL_SOCKET, SO_DEBUG,
648 		    (char *)&on, sizeof(on));
649 	if (options & SO_DONTROUTE)
650 		(void) setsockopt(rcvsock, SOL_SOCKET, SO_DONTROUTE,
651 		    (char *)&on, sizeof(on));
652 #ifdef IPSEC
653 #ifdef IPSEC_POLICY_IPSEC
654 	/*
655 	 * do not raise error even if setsockopt fails, kernel may have ipsec
656 	 * turned off.
657 	 */
658 	if (setpolicy(rcvsock, "in bypass") < 0)
659 		errx(1, "%s", ipsec_strerror());
660 	if (setpolicy(rcvsock, "out bypass") < 0)
661 		errx(1, "%s", ipsec_strerror());
662 #else
663     {
664 	int level = IPSEC_LEVEL_NONE;
665 
666 	(void)setsockopt(rcvsock, IPPROTO_IPV6, IPV6_ESP_TRANS_LEVEL, &level,
667 	    sizeof(level));
668 	(void)setsockopt(rcvsock, IPPROTO_IPV6, IPV6_ESP_NETWORK_LEVEL, &level,
669 	    sizeof(level));
670 #ifdef IP_AUTH_TRANS_LEVEL
671 	(void)setsockopt(rcvsock, IPPROTO_IPV6, IPV6_AUTH_TRANS_LEVEL, &level,
672 	    sizeof(level));
673 #else
674 	(void)setsockopt(rcvsock, IPPROTO_IPV6, IPV6_AUTH_LEVEL, &level,
675 	    sizeof(level));
676 #endif
677 #ifdef IP_AUTH_NETWORK_LEVEL
678 	(void)setsockopt(rcvsock, IPPROTO_IPV6, IPV6_AUTH_NETWORK_LEVEL, &level,
679 	    sizeof(level));
680 #endif
681     }
682 #endif /*IPSEC_POLICY_IPSEC*/
683 #endif /*IPSEC*/
684 
685 	/*
686 	 * Send UDP or ICMP
687 	 */
688 	if (useicmp) {
689 		sndsock = rcvsock;
690 	} else {
691 		if ((sndsock = socket(AF_INET6, SOCK_DGRAM, 0)) < 0) {
692 			perror("socket(SOCK_DGRAM)");
693 			exit(5);
694 		}
695 	}
696 #ifdef SO_SNDBUF
697 	i = datalen;
698 	if (setsockopt(sndsock, SOL_SOCKET, SO_SNDBUF, (char *)&i,
699 	    sizeof(i)) < 0) {
700 		perror("setsockopt(SO_SNDBUF)");
701 		exit(6);
702 	}
703 #endif /* SO_SNDBUF */
704 	if (options & SO_DEBUG)
705 		(void) setsockopt(sndsock, SOL_SOCKET, SO_DEBUG,
706 		    (char *)&on, sizeof(on));
707 	if (options & SO_DONTROUTE)
708 		(void) setsockopt(sndsock, SOL_SOCKET, SO_DONTROUTE,
709 		    (char *)&on, sizeof(on));
710 #ifdef USE_RFC2292BIS
711 	if (rth) {/* XXX: there is no library to finalize the header... */
712 		rth->ip6r_len = rth->ip6r_segleft * 2;
713 		if (setsockopt(sndsock, IPPROTO_IPV6, IPV6_RTHDR,
714 		    (void *)rth, (rth->ip6r_len + 1) << 3)) {
715 			fprintf(stderr, "setsockopt(IPV6_RTHDR): %s\n",
716 			    strerror(errno));
717 			exit(1);
718 		}
719 	}
720 #else  /* old advanced API */
721 	if (cmsg != NULL) {
722 		inet6_rthdr_lasthop(cmsg, IPV6_RTHDR_LOOSE);
723 		if (setsockopt(sndsock, IPPROTO_IPV6, IPV6_PKTOPTIONS,
724 		    rtbuf, cmsg->cmsg_len) < 0) {
725 			fprintf(stderr, "setsockopt(IPV6_PKTOPTIONS): %s\n",
726 			    strerror(errno));
727 			exit(1);
728 		}
729 	}
730 #endif /* USE_RFC2292BIS */
731 #ifdef IPSEC
732 #ifdef IPSEC_POLICY_IPSEC
733 	/*
734 	 * do not raise error even if setsockopt fails, kernel may have ipsec
735 	 * turned off.
736 	 */
737 	if (setpolicy(sndsock, "in bypass") < 0)
738 		errx(1, "%s", ipsec_strerror());
739 	if (setpolicy(sndsock, "out bypass") < 0)
740 		errx(1, "%s", ipsec_strerror());
741 #else
742     {
743 	int level = IPSEC_LEVEL_BYPASS;
744 
745 	(void)setsockopt(sndsock, IPPROTO_IPV6, IPV6_ESP_TRANS_LEVEL, &level,
746 	    sizeof(level));
747 	(void)setsockopt(sndsock, IPPROTO_IPV6, IPV6_ESP_NETWORK_LEVEL, &level,
748 	    sizeof(level));
749 #ifdef IP_AUTH_TRANS_LEVEL
750 	(void)setsockopt(sndsock, IPPROTO_IPV6, IPV6_AUTH_TRANS_LEVEL, &level,
751 	    sizeof(level));
752 #else
753 	(void)setsockopt(sndsock, IPPROTO_IPV6, IPV6_AUTH_LEVEL, &level,
754 	    sizeof(level));
755 #endif
756 #ifdef IP_AUTH_NETWORK_LEVEL
757 	(void)setsockopt(sndsock, IPPROTO_IPV6, IPV6_AUTH_NETWORK_LEVEL, &level,
758 	    sizeof(level));
759 #endif
760     }
761 #endif /*IPSEC_POLICY_IPSEC*/
762 #endif /*IPSEC*/
763 
764 	/*
765 	 * Source selection
766 	 */
767 	bzero(&Src, sizeof(Src));
768 	if (source) {
769 		struct addrinfo hints, *res;
770 		int error;
771 
772 		memset(&hints, 0, sizeof(hints));
773 		hints.ai_family = AF_INET6;
774 		hints.ai_socktype = SOCK_DGRAM;	/*dummy*/
775 		hints.ai_flags = AI_NUMERICHOST;
776 		error = getaddrinfo(source, "0", &hints, &res);
777 		if (error) {
778 			printf("traceroute6: %s: %s\n", source,
779 			    gai_strerror(error));
780 			exit(1);
781 		}
782 		if (res->ai_addrlen > sizeof(Src)) {
783 			printf("traceroute6: %s: %s\n", source,
784 			    gai_strerror(error));
785 			exit(1);
786 		}
787 		memcpy(&Src, res->ai_addr, res->ai_addrlen);
788 		freeaddrinfo(res);
789 	} else {
790 		struct sockaddr_in6 Nxt;
791 		int dummy;
792 		socklen_t len;
793 
794 		Nxt = Dst;
795 		Nxt.sin6_port = htons(DUMMY_PORT);
796 		if (cmsg != NULL)
797 			bcopy(inet6_rthdr_getaddr(cmsg, 1), &Nxt.sin6_addr,
798 			    sizeof(Nxt.sin6_addr));
799 		if ((dummy = socket(AF_INET6, SOCK_DGRAM, 0)) < 0) {
800 			perror("socket");
801 			exit(1);
802 		}
803 		if (connect(dummy, (struct sockaddr *)&Nxt, Nxt.sin6_len) < 0) {
804 			perror("connect");
805 			exit(1);
806 		}
807 		len = sizeof(Src);
808 		if (getsockname(dummy, (struct sockaddr *)&Src, &len) < 0) {
809 			perror("getsockname");
810 			exit(1);
811 		}
812 		if (getnameinfo((struct sockaddr *)&Src, Src.sin6_len,
813 		    src0, sizeof(src0), NULL, 0, NI_NUMERICHOST)) {
814 			fprintf(stderr, "getnameinfo failed for source\n");
815 			exit(1);
816 		}
817 		source = src0;
818 		close(dummy);
819 	}
820 
821 	Src.sin6_port = htons(0);
822 	if (bind(sndsock, (struct sockaddr *)&Src, Src.sin6_len) < 0) {
823 		perror("bind");
824 		exit(1);
825 	}
826 
827 	{
828 		socklen_t len;
829 
830 		len = sizeof(Src);
831 		if (getsockname(sndsock, (struct sockaddr *)&Src, &len) < 0) {
832 			perror("getsockname");
833 			exit(1);
834 		}
835 		srcport = ntohs(Src.sin6_port);
836 	}
837 
838 	/*
839 	 * Message to users
840 	 */
841 	if (getnameinfo((struct sockaddr *)&Dst, Dst.sin6_len, hbuf,
842 	    sizeof(hbuf), NULL, 0, NI_NUMERICHOST))
843 		strlcpy(hbuf, "(invalid)", sizeof(hbuf));
844 	fprintf(stderr, "traceroute6");
845 	fprintf(stderr, " to %s (%s)", hostname, hbuf);
846 	if (source)
847 		fprintf(stderr, " from %s", source);
848 	fprintf(stderr, ", %lu hops max, %lu byte packets\n",
849 	    max_hops, datalen);
850 	(void) fflush(stderr);
851 
852 	if (first_hop > 1)
853 		printf("Skipping %lu intermediate hops\n", first_hop - 1);
854 
855 	/*
856 	 * Main loop
857 	 */
858 	for (hops = first_hop; hops <= max_hops; ++hops) {
859 		struct in6_addr lastaddr;
860 		int got_there = 0;
861 		int unreachable = 0;
862 
863 		printf("%2lu ", hops);
864 		bzero(&lastaddr, sizeof(lastaddr));
865 		for (probe = 0; probe < nprobes; ++probe) {
866 			int cc;
867 			struct timeval t1, t2;
868 
869 			(void) gettimeofday(&t1, NULL);
870 			send_probe(++seq, hops);
871 			while ((cc = wait_for_reply(rcvsock, &rcvmhdr))) {
872 				(void) gettimeofday(&t2, NULL);
873 				if ((i = packet_ok(&rcvmhdr, cc, seq))) {
874 					if (!IN6_ARE_ADDR_EQUAL(&Rcv.sin6_addr,
875 					    &lastaddr)) {
876 						if (probe > 0)
877 							fputs("\n   ", stdout);
878 						print(&rcvmhdr, cc);
879 						lastaddr = Rcv.sin6_addr;
880 					}
881 					printf("  %.3f ms", deltaT(&t1, &t2));
882 					switch (i - 1) {
883 					case ICMP6_DST_UNREACH_NOROUTE:
884 						++unreachable;
885 						printf(" !N");
886 						break;
887 					case ICMP6_DST_UNREACH_ADMIN:
888 						++unreachable;
889 						printf(" !P");
890 						break;
891 					case ICMP6_DST_UNREACH_NOTNEIGHBOR:
892 						++unreachable;
893 						printf(" !S");
894 						break;
895 					case ICMP6_DST_UNREACH_ADDR:
896 						++unreachable;
897 						printf(" !A");
898 						break;
899 					case ICMP6_DST_UNREACH_NOPORT:
900 						if (rcvhlim >= 0 &&
901 						    rcvhlim <= 1)
902 							printf(" !");
903 						++got_there;
904 						break;
905 					}
906 					break;
907 				}
908 			}
909 			if (cc == 0)
910 				printf(" *");
911 			(void) fflush(stdout);
912 		}
913 		putchar('\n');
914 		if (got_there ||
915 		    (unreachable > 0 && unreachable >= ((nprobes + 1) / 2))) {
916 			exit(0);
917 		}
918 	}
919 
920 	exit(0);
921 }
922 
923 int
924 wait_for_reply(sock, mhdr)
925 	int sock;
926 	struct msghdr *mhdr;
927 {
928 #ifdef HAVE_POLL
929 	struct pollfd pfd[1];
930 	int cc = 0;
931 
932 	pfd[0].fd = sock;
933 	pfd[0].events = POLLIN;
934 	pfd[0].revents = 0;
935 
936 	if (poll(pfd, 1, waittime * 1000) > 0)
937 		cc = recvmsg(rcvsock, mhdr, 0);
938 
939 	return(cc);
940 #else
941 	fd_set *fdsp;
942 	struct timeval wait;
943 	int cc = 0, fdsn;
944 
945 	fdsn = howmany(sock + 1, NFDBITS) * sizeof(fd_mask);
946 	if ((fdsp = (fd_set *)malloc(fdsn)) == NULL)
947 		err(1, "malloc");
948 	memset(fdsp, 0, fdsn);
949 	FD_SET(sock, fdsp);
950 	wait.tv_sec = waittime; wait.tv_usec = 0;
951 
952 	if (select(sock+1, fdsp, (fd_set *)0, (fd_set *)0, &wait) > 0)
953 		cc = recvmsg(rcvsock, mhdr, 0);
954 
955 	free(fdsp);
956 	return(cc);
957 #endif
958 }
959 
960 #ifdef IPSEC
961 #ifdef IPSEC_POLICY_IPSEC
962 int
963 setpolicy(so, policy)
964 	int so;
965 	char *policy;
966 {
967 	char *buf;
968 
969 	buf = ipsec_set_policy(policy, strlen(policy));
970 	if (buf == NULL) {
971 		warnx("%s", ipsec_strerror());
972 		return -1;
973 	}
974 	(void)setsockopt(so, IPPROTO_IPV6, IPV6_IPSEC_POLICY,
975 	    buf, ipsec_get_policylen(buf));
976 
977 	free(buf);
978 
979 	return 0;
980 }
981 #endif
982 #endif
983 
984 void
985 send_probe(seq, hops)
986 	int seq;
987 	u_long hops;
988 {
989 	struct timeval tv;
990 	struct tv32 tv32;
991 	int i;
992 
993 	i = hops;
994 	if (setsockopt(sndsock, IPPROTO_IPV6, IPV6_UNICAST_HOPS,
995 	    (char *)&i, sizeof(i)) < 0) {
996 		perror("setsockopt IPV6_UNICAST_HOPS");
997 	}
998 
999 	Dst.sin6_port = htons(port + seq);
1000 	(void) gettimeofday(&tv, NULL);
1001 	tv32.tv32_sec = htonl(tv.tv_sec);
1002 	tv32.tv32_usec = htonl(tv.tv_usec);
1003 
1004 	if (useicmp) {
1005 		struct icmp6_hdr *icp = (struct icmp6_hdr *)outpacket;
1006 
1007 		icp->icmp6_type = ICMP6_ECHO_REQUEST;
1008 		icp->icmp6_code = 0;
1009 		icp->icmp6_cksum = 0;
1010 		icp->icmp6_id = ident;
1011 		icp->icmp6_seq = htons(seq);
1012 		bcopy(&tv32, ((u_int8_t *)outpacket + ICMP6ECHOLEN),
1013 		    sizeof(tv32));
1014 	} else {
1015 		struct opacket *op = outpacket;
1016 
1017 		op->seq = seq;
1018 		op->hops = hops;
1019 		bcopy(&tv32, &op->tv, sizeof tv32);
1020 	}
1021 
1022 	i = sendto(sndsock, (char *)outpacket, datalen, 0,
1023 	    (struct sockaddr *)&Dst, Dst.sin6_len);
1024 	if (i < 0 || i != datalen)  {
1025 		if (i < 0)
1026 			perror("sendto");
1027 		printf("traceroute6: wrote %s %lu chars, ret=%d\n",
1028 		    hostname, datalen, i);
1029 		(void) fflush(stdout);
1030 	}
1031 }
1032 
1033 int
1034 get_hoplim(mhdr)
1035 	struct msghdr *mhdr;
1036 {
1037 	struct cmsghdr *cm;
1038 
1039 	for (cm = (struct cmsghdr *)CMSG_FIRSTHDR(mhdr); cm;
1040 	    cm = (struct cmsghdr *)CMSG_NXTHDR(mhdr, cm)) {
1041 		if (cm->cmsg_level == IPPROTO_IPV6 &&
1042 		    cm->cmsg_type == IPV6_HOPLIMIT &&
1043 		    cm->cmsg_len == CMSG_LEN(sizeof(int)))
1044 			return(*(int *)CMSG_DATA(cm));
1045 	}
1046 
1047 	return(-1);
1048 }
1049 
1050 double
1051 deltaT(t1p, t2p)
1052 	struct timeval *t1p, *t2p;
1053 {
1054 	double dt;
1055 
1056 	dt = (double)(t2p->tv_sec - t1p->tv_sec) * 1000.0 +
1057 	    (double)(t2p->tv_usec - t1p->tv_usec) / 1000.0;
1058 	return (dt);
1059 }
1060 
1061 /*
1062  * Convert an ICMP "type" field to a printable string.
1063  */
1064 char *
1065 pr_type(t0)
1066 	int t0;
1067 {
1068 	u_char t = t0 & 0xff;
1069 	char *cp;
1070 
1071 	switch (t) {
1072 	case ICMP6_DST_UNREACH:
1073 		cp = "Destination Unreachable";
1074 		break;
1075 	case ICMP6_PACKET_TOO_BIG:
1076 		cp = "Packet Too Big";
1077 		break;
1078 	case ICMP6_TIME_EXCEEDED:
1079 		cp = "Time Exceeded";
1080 		break;
1081 	case ICMP6_PARAM_PROB:
1082 		cp = "Parameter Problem";
1083 		break;
1084 	case ICMP6_ECHO_REQUEST:
1085 		cp = "Echo Request";
1086 		break;
1087 	case ICMP6_ECHO_REPLY:
1088 		cp = "Echo Reply";
1089 		break;
1090 	case ICMP6_MEMBERSHIP_QUERY:
1091 		cp = "Group Membership Query";
1092 		break;
1093 	case ICMP6_MEMBERSHIP_REPORT:
1094 		cp = "Group Membership Report";
1095 		break;
1096 	case ICMP6_MEMBERSHIP_REDUCTION:
1097 		cp = "Group Membership Reduction";
1098 		break;
1099 	case ND_ROUTER_SOLICIT:
1100 		cp = "Router Solicitation";
1101 		break;
1102 	case ND_ROUTER_ADVERT:
1103 		cp = "Router Advertisement";
1104 		break;
1105 	case ND_NEIGHBOR_SOLICIT:
1106 		cp = "Neighbor Solicitation";
1107 		break;
1108 	case ND_NEIGHBOR_ADVERT:
1109 		cp = "Neighbor Advertisement";
1110 		break;
1111 	case ND_REDIRECT:
1112 		cp = "Redirect";
1113 		break;
1114 	default:
1115 		cp = "Unknown";
1116 		break;
1117 	}
1118 	return cp;
1119 }
1120 
1121 int
1122 packet_ok(mhdr, cc, seq)
1123 	struct msghdr *mhdr;
1124 	int cc;
1125 	int seq;
1126 {
1127 	struct icmp6_hdr *icp;
1128 	struct sockaddr_in6 *from = (struct sockaddr_in6 *)mhdr->msg_name;
1129 	u_char type, code;
1130 	char *buf = (char *)mhdr->msg_iov[0].iov_base;
1131 	struct cmsghdr *cm;
1132 	int *hlimp;
1133 	char hbuf[NI_MAXHOST];
1134 
1135 #ifdef OLDRAWSOCKET
1136 	int hlen;
1137 	struct ip6_hdr *ip;
1138 #endif
1139 
1140 #ifdef OLDRAWSOCKET
1141 	ip = (struct ip6_hdr *) buf;
1142 	hlen = sizeof(struct ip6_hdr);
1143 	if (cc < hlen + sizeof(struct icmp6_hdr)) {
1144 		if (verbose) {
1145 			if (getnameinfo((struct sockaddr *)from, from->sin6_len,
1146 			    hbuf, sizeof(hbuf), NULL, 0, NI_NUMERICHOST) != 0)
1147 				strlcpy(hbuf, "invalid", sizeof(hbuf));
1148 			printf("packet too short (%d bytes) from %s\n", cc,
1149 			    hbuf);
1150 		}
1151 		return (0);
1152 	}
1153 	cc -= hlen;
1154 	icp = (struct icmp6_hdr *)(buf + hlen);
1155 #else
1156 	if (cc < sizeof(struct icmp6_hdr)) {
1157 		if (verbose) {
1158 			if (getnameinfo((struct sockaddr *)from, from->sin6_len,
1159 			    hbuf, sizeof(hbuf), NULL, 0, NI_NUMERICHOST) != 0)
1160 				strlcpy(hbuf, "invalid", sizeof(hbuf));
1161 			printf("data too short (%d bytes) from %s\n", cc, hbuf);
1162 		}
1163 		return(0);
1164 	}
1165 	icp = (struct icmp6_hdr *)buf;
1166 #endif
1167 	/* get optional information via advanced API */
1168 	rcvpktinfo = NULL;
1169 	hlimp = NULL;
1170 	for (cm = (struct cmsghdr *)CMSG_FIRSTHDR(mhdr); cm;
1171 	    cm = (struct cmsghdr *)CMSG_NXTHDR(mhdr, cm)) {
1172 		if (cm->cmsg_level == IPPROTO_IPV6 &&
1173 		    cm->cmsg_type == IPV6_PKTINFO &&
1174 		    cm->cmsg_len ==
1175 		    CMSG_LEN(sizeof(struct in6_pktinfo)))
1176 			rcvpktinfo = (struct in6_pktinfo *)(CMSG_DATA(cm));
1177 
1178 		if (cm->cmsg_level == IPPROTO_IPV6 &&
1179 		    cm->cmsg_type == IPV6_HOPLIMIT &&
1180 		    cm->cmsg_len == CMSG_LEN(sizeof(int)))
1181 			hlimp = (int *)CMSG_DATA(cm);
1182 	}
1183 	if (rcvpktinfo == NULL || hlimp == NULL) {
1184 		warnx("failed to get received hop limit or packet info");
1185 #if 0
1186 		return(0);
1187 #else
1188 		rcvhlim = 0;	/*XXX*/
1189 #endif
1190 	}
1191 	else
1192 		rcvhlim = *hlimp;
1193 
1194 	type = icp->icmp6_type;
1195 	code = icp->icmp6_code;
1196 	if ((type == ICMP6_TIME_EXCEEDED && code == ICMP6_TIME_EXCEED_TRANSIT)
1197 	    || type == ICMP6_DST_UNREACH) {
1198 		struct ip6_hdr *hip;
1199 		struct udphdr *up;
1200 
1201 		hip = (struct ip6_hdr *)(icp + 1);
1202 		if ((up = get_udphdr(hip, (u_char *)(buf + cc))) == NULL) {
1203 			if (verbose)
1204 				warnx("failed to get upper layer header");
1205 			return(0);
1206 		}
1207 		if (useicmp &&
1208 		    ((struct icmp6_hdr *)up)->icmp6_id == ident &&
1209 		    ((struct icmp6_hdr *)up)->icmp6_seq == htons(seq))
1210 			return (type == ICMP6_TIME_EXCEEDED ? -1 : code + 1);
1211 		else if (!useicmp &&
1212 		    up->uh_sport == htons(srcport) &&
1213 		    up->uh_dport == htons(port + seq))
1214 			return (type == ICMP6_TIME_EXCEEDED ? -1 : code + 1);
1215 	} else if (useicmp && type == ICMP6_ECHO_REPLY) {
1216 		if (icp->icmp6_id == ident &&
1217 		    icp->icmp6_seq == htons(seq))
1218 			return (ICMP6_DST_UNREACH_NOPORT + 1);
1219 	}
1220 	if (verbose) {
1221 		char sbuf[NI_MAXHOST+1], dbuf[INET6_ADDRSTRLEN];
1222 		u_int8_t *p;
1223 		int i;
1224 
1225 		if (getnameinfo((struct sockaddr *)from, from->sin6_len,
1226 		    sbuf, sizeof(sbuf), NULL, 0, NI_NUMERICHOST) != 0)
1227 			strlcpy(sbuf, "invalid", sizeof(sbuf));
1228 		printf("\n%d bytes from %s to %s", cc, sbuf,
1229 		    rcvpktinfo ? inet_ntop(AF_INET6, &rcvpktinfo->ipi6_addr,
1230 		    dbuf, sizeof(dbuf)) : "?");
1231 		printf(": icmp type %d (%s) code %d\n", type, pr_type(type),
1232 		    icp->icmp6_code);
1233 		p = (u_int8_t *)(icp + 1);
1234 #define WIDTH	16
1235 		for (i = 0; i < cc; i++) {
1236 			if (i % WIDTH == 0)
1237 				printf("%04x:", i);
1238 			if (i % 4 == 0)
1239 				printf(" ");
1240 			printf("%02x", p[i]);
1241 			if (i % WIDTH == WIDTH - 1)
1242 				printf("\n");
1243 		}
1244 		if (cc % WIDTH != 0)
1245 			printf("\n");
1246 	}
1247 	return(0);
1248 }
1249 
1250 /*
1251  * Increment pointer until find the UDP or ICMP header.
1252  */
1253 struct udphdr *
1254 get_udphdr(ip6, lim)
1255 	struct ip6_hdr *ip6;
1256 	u_char *lim;
1257 {
1258 	u_char *cp = (u_char *)ip6, nh;
1259 	int hlen;
1260 
1261 	if (cp + sizeof(*ip6) >= lim)
1262 		return(NULL);
1263 
1264 	nh = ip6->ip6_nxt;
1265 	cp += sizeof(struct ip6_hdr);
1266 
1267 	while (lim - cp >= 8) {
1268 		switch (nh) {
1269 		case IPPROTO_ESP:
1270 		case IPPROTO_TCP:
1271 			return(NULL);
1272 		case IPPROTO_ICMPV6:
1273 			return(useicmp ? (struct udphdr *)cp : NULL);
1274 		case IPPROTO_UDP:
1275 			return(useicmp ? NULL : (struct udphdr *)cp);
1276 		case IPPROTO_FRAGMENT:
1277 			hlen = sizeof(struct ip6_frag);
1278 			nh = ((struct ip6_frag *)cp)->ip6f_nxt;
1279 			break;
1280 		case IPPROTO_AH:
1281 			hlen = (((struct ip6_ext *)cp)->ip6e_len + 2) << 2;
1282 			nh = ((struct ip6_ext *)cp)->ip6e_nxt;
1283 			break;
1284 		default:
1285 			hlen = (((struct ip6_ext *)cp)->ip6e_len + 1) << 3;
1286 			nh = ((struct ip6_ext *)cp)->ip6e_nxt;
1287 			break;
1288 		}
1289 
1290 		cp += hlen;
1291 	}
1292 
1293 	return(NULL);
1294 }
1295 
1296 void
1297 print(mhdr, cc)
1298 	struct msghdr *mhdr;
1299 	int cc;
1300 {
1301 	struct sockaddr_in6 *from = (struct sockaddr_in6 *)mhdr->msg_name;
1302 	char hbuf[NI_MAXHOST];
1303 
1304 	if (getnameinfo((struct sockaddr *)from, from->sin6_len,
1305 	    hbuf, sizeof(hbuf), NULL, 0, NI_NUMERICHOST) != 0)
1306 		strlcpy(hbuf, "invalid", sizeof(hbuf));
1307 	if (nflag)
1308 		printf(" %s", hbuf);
1309 	else if (lflag)
1310 		printf(" %s (%s)", inetname((struct sockaddr *)from), hbuf);
1311 	else
1312 		printf(" %s", inetname((struct sockaddr *)from));
1313 
1314 	if (verbose) {
1315 #ifdef OLDRAWSOCKET
1316 		printf(" %d bytes to %s", cc,
1317 		    rcvpktinfo ? inet_ntop(AF_INET6, &rcvpktinfo->ipi6_addr,
1318 		    hbuf, sizeof(hbuf)) : "?");
1319 #else
1320 		printf(" %d bytes of data to %s", cc,
1321 		    rcvpktinfo ?  inet_ntop(AF_INET6, &rcvpktinfo->ipi6_addr,
1322 		    hbuf, sizeof(hbuf)) : "?");
1323 #endif
1324 	}
1325 }
1326 
1327 /*
1328  * Construct an Internet address representation.
1329  * If the nflag has been supplied, give
1330  * numeric value, otherwise try for symbolic name.
1331  */
1332 const char *
1333 inetname(sa)
1334 	struct sockaddr *sa;
1335 {
1336 	static char line[NI_MAXHOST], domain[MAXHOSTNAMELEN + 1];
1337 	static int first = 1;
1338 	char *cp;
1339 
1340 	if (first && !nflag) {
1341 		first = 0;
1342 		if (gethostname(domain, sizeof(domain)) == 0 &&
1343 		    (cp = strchr(domain, '.')))
1344 			(void) strlcpy(domain, cp + 1, sizeof(domain));
1345 		else
1346 			domain[0] = 0;
1347 	}
1348 	cp = NULL;
1349 	if (!nflag) {
1350 		if (getnameinfo(sa, sa->sa_len, line, sizeof(line), NULL, 0,
1351 		    NI_NAMEREQD) == 0) {
1352 			if ((cp = strchr(line, '.')) &&
1353 			    !strcmp(cp + 1, domain))
1354 				*cp = 0;
1355 			cp = line;
1356 		}
1357 	}
1358 	if (cp)
1359 		return cp;
1360 
1361 	if (getnameinfo(sa, sa->sa_len, line, sizeof(line), NULL, 0,
1362 	    NI_NUMERICHOST) != 0)
1363 		strlcpy(line, "invalid", sizeof(line));
1364 	return line;
1365 }
1366 
1367 void
1368 usage()
1369 {
1370 
1371 	fprintf(stderr,
1372 "usage: traceroute6 [-dIlnrv] [-f firsthop] [-g gateway] [-m hoplimit]\n"
1373 "       [-p port] [-q probes] [-s src] [-w waittime] target [datalen]\n");
1374 	exit(1);
1375 }
1376