xref: /freebsd/usr.sbin/traceroute6/traceroute6.c (revision 2b743a9e9ddc6736208dc8ca1ce06ce64ad20a19)
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 <netinet6/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 __P((int, char *[]));
313 int	wait_for_reply __P((int, struct msghdr *));
314 #ifdef IPSEC
315 #ifdef IPSEC_POLICY_IPSEC
316 int	setpolicy __P((int so, char *policy));
317 #endif
318 #endif
319 void	send_probe __P((int, u_long));
320 struct udphdr *get_udphdr __P((struct ip6_hdr *, u_char *));
321 int	get_hoplim __P((struct msghdr *));
322 double	deltaT __P((struct timeval *, struct timeval *));
323 char	*pr_type __P((int));
324 int	packet_ok __P((struct msghdr *, int, int));
325 void	print __P((struct msghdr *, int));
326 const char *inetname __P((struct sockaddr *));
327 void	usage __P((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 
377 	/*
378 	 * Receive ICMP
379 	 */
380 	if ((rcvsock = socket(AF_INET6, SOCK_RAW, IPPROTO_ICMPV6)) < 0) {
381 		perror("socket(ICMPv6)");
382 		exit(5);
383 	}
384 
385 	/* revoke privs */
386 	seteuid(getuid());
387 	setuid(getuid());
388 
389 	size = sizeof(i);
390 	(void) sysctl(mib, sizeof(mib)/sizeof(mib[0]), &i, &size, NULL, 0);
391 	max_hops = i;
392 
393 	/* specify to tell receiving interface */
394 #ifdef IPV6_RECVPKTINFO
395 	if (setsockopt(rcvsock, IPPROTO_IPV6, IPV6_RECVPKTINFO, &on,
396 	    sizeof(on)) < 0)
397 		err(1, "setsockopt(IPV6_RECVPKTINFO)");
398 #else  /* old adv. API */
399 	if (setsockopt(rcvsock, IPPROTO_IPV6, IPV6_PKTINFO, &on,
400 	    sizeof(on)) < 0)
401 		err(1, "setsockopt(IPV6_PKTINFO)");
402 #endif
403 
404 	/* specify to tell value of hoplimit field of received IP6 hdr */
405 #ifdef IPV6_RECVHOPLIMIT
406 	if (setsockopt(rcvsock, IPPROTO_IPV6, IPV6_RECVHOPLIMIT, &on,
407 	    sizeof(on)) < 0)
408 		err(1, "setsockopt(IPV6_RECVHOPLIMIT)");
409 #else  /* old adv. API */
410 	if (setsockopt(rcvsock, IPPROTO_IPV6, IPV6_HOPLIMIT, &on,
411 	    sizeof(on)) < 0)
412 		err(1, "setsockopt(IPV6_HOPLIMIT)");
413 #endif
414 
415 	seq = 0;
416 
417 	while ((ch = getopt(argc, argv, "df:g:Ilm:np:q:rs:w:v")) != -1)
418 		switch (ch) {
419 		case 'd':
420 			options |= SO_DEBUG;
421 			break;
422 		case 'f':
423 			ep = NULL;
424 			errno = 0;
425 			first_hop = strtoul(optarg, &ep, 0);
426 			if (errno || !*optarg || *ep || first_hop > 255) {
427 				fprintf(stderr,
428 				    "traceroute6: invalid min hoplimit.\n");
429 				exit(1);
430 			}
431 			break;
432 		case 'g':
433 			hp = getipnodebyname(optarg, AF_INET6, 0, &h_errno);
434 			if (hp == NULL) {
435 				fprintf(stderr,
436 				    "traceroute6: unknown host %s\n", optarg);
437 				exit(1);
438 			}
439 #ifdef USE_RFC2292BIS
440 			if (rth == NULL) {
441 				/*
442 				 * XXX: We can't detect the number of
443 				 * intermediate nodes yet.
444 				 */
445 				if ((rth = inet6_rth_init((void *)rtbuf,
446 				    sizeof(rtbuf), IPV6_RTHDR_TYPE_0,
447 				    0)) == NULL) {
448 					fprintf(stderr,
449 					    "inet6_rth_init failed.\n");
450 					exit(1);
451 				}
452 			}
453 			if (inet6_rth_add((void *)rth,
454 			    (struct in6_addr *)hp->h_addr)) {
455 				fprintf(stderr,
456 				    "inet6_rth_add failed for %s\n",
457 				    optarg);
458 				exit(1);
459 			}
460 #else  /* old advanced API */
461 			if (cmsg == NULL)
462 				cmsg = inet6_rthdr_init(rtbuf, IPV6_RTHDR_TYPE_0);
463 			inet6_rthdr_add(cmsg, (struct in6_addr *)hp->h_addr,
464 			    IPV6_RTHDR_LOOSE);
465 #endif
466 			freehostent(hp);
467 			break;
468 		case 'I':
469 			useicmp++;
470 			ident = htons(getpid() & 0xffff); /* same as ping6 */
471 			break;
472 		case 'l':
473 			lflag++;
474 			break;
475 		case 'm':
476 			ep = NULL;
477 			errno = 0;
478 			max_hops = strtoul(optarg, &ep, 0);
479 			if (errno || !*optarg || *ep || max_hops > 255) {
480 				fprintf(stderr,
481 				    "traceroute6: invalid max hoplimit.\n");
482 				exit(1);
483 			}
484 			break;
485 		case 'n':
486 			nflag++;
487 			break;
488 		case 'p':
489 			ep = NULL;
490 			errno = 0;
491 			lport = strtoul(optarg, &ep, 0);
492 			if (errno || !*optarg || *ep) {
493 				fprintf(stderr, "traceroute6: invalid port.\n");
494 				exit(1);
495 			}
496 			if (lport == 0 || lport != (lport & 0xffff)) {
497 				fprintf(stderr,
498 				    "traceroute6: port out of range.\n");
499 				exit(1);
500 			}
501 			port = lport & 0xffff;
502 			break;
503 		case 'q':
504 			ep = NULL;
505 			errno = 0;
506 			nprobes = strtoul(optarg, &ep, 0);
507 			if (errno || !*optarg || *ep) {
508 				fprintf(stderr,
509 				    "traceroute6: invalid nprobes.\n");
510 				exit(1);
511 			}
512 			if (nprobes < 1) {
513 				fprintf(stderr,
514 				    "traceroute6: nprobes must be >0.\n");
515 				exit(1);
516 			}
517 			break;
518 		case 'r':
519 			options |= SO_DONTROUTE;
520 			break;
521 		case 's':
522 			/*
523 			 * set the ip source address of the outbound
524 			 * probe (e.g., on a multi-homed host).
525 			 */
526 			source = optarg;
527 			break;
528 		case 'v':
529 			verbose++;
530 			break;
531 		case 'w':
532 			ep = NULL;
533 			errno = 0;
534 			waittime = strtoul(optarg, &ep, 0);
535 			if (errno || !*optarg || *ep) {
536 				fprintf(stderr,
537 				    "traceroute6: invalid wait time.\n");
538 				exit(1);
539 			}
540 			if (waittime <= 1) {
541 				fprintf(stderr,
542 				    "traceroute6: wait must be >1 sec.\n");
543 				exit(1);
544 			}
545 			break;
546 		default:
547 			usage();
548 		}
549 	argc -= optind;
550 	argv += optind;
551 
552 	if (max_hops < first_hop) {
553 		fprintf(stderr,
554 		    "traceroute6: max hoplimit must be larger than first hoplimit.\n");
555 		exit(1);
556 	}
557 
558 	if (argc < 1 || argc > 2)
559 		usage();
560 
561 #if 1
562 	setvbuf(stdout, NULL, _IOLBF, BUFSIZ);
563 #else
564 	setlinebuf(stdout);
565 #endif
566 
567 	memset(&hints, 0, sizeof(hints));
568 	hints.ai_family = PF_INET6;
569 	hints.ai_socktype = SOCK_RAW;
570 	hints.ai_protocol = IPPROTO_ICMPV6;
571 	hints.ai_flags = AI_CANONNAME;
572 	error = getaddrinfo(*argv, NULL, &hints, &res);
573 	if (error) {
574 		fprintf(stderr,
575 		    "traceroute6: %s\n", gai_strerror(error));
576 		exit(1);
577 	}
578 	if (res->ai_addrlen != sizeof(Dst)) {
579 		fprintf(stderr,
580 		    "traceroute6: size of sockaddr mismatch\n");
581 		exit(1);
582 	}
583 	memcpy(&Dst, res->ai_addr, res->ai_addrlen);
584 	hostname = res->ai_canonname ? strdup(res->ai_canonname) : *argv;
585 	if (!hostname) {
586 		fprintf(stderr, "traceroute6: not enough core\n");
587 		exit(1);
588 	}
589 	if (res->ai_next) {
590 		if (getnameinfo(res->ai_addr, res->ai_addrlen, hbuf,
591 		    sizeof(hbuf), NULL, 0, NI_NUMERICHOST) != 0)
592 			strlcpy(hbuf, "?", sizeof(hbuf));
593 		fprintf(stderr, "traceroute6: Warning: %s has multiple "
594 		    "addresses; using %s\n", hostname, hbuf);
595 	}
596 
597 	if (*++argv) {
598 		ep = NULL;
599 		errno = 0;
600 		datalen = strtoul(*argv, &ep, 0);
601 		if (errno || !*argv || *ep) {
602 			fprintf(stderr,
603 			    "traceroute6: invalid packet length.\n");
604 			exit(1);
605 		}
606 	}
607 	if (useicmp)
608 		minlen = ICMP6ECHOLEN + sizeof(struct tv32);
609 	else
610 		minlen = sizeof(struct opacket);
611 	if (datalen < minlen)
612 		datalen = minlen;
613 	else if (datalen >= MAXPACKET) {
614 		fprintf(stderr,
615 		    "traceroute6: packet size must be %d <= s < %ld.\n",
616 		    minlen, (long)MAXPACKET);
617 		exit(1);
618 	}
619 	outpacket = (struct opacket *)malloc((unsigned)datalen);
620 	if (!outpacket) {
621 		perror("malloc");
622 		exit(1);
623 	}
624 	(void) bzero((char *)outpacket, datalen);
625 
626 	/* initialize msghdr for receiving packets */
627 	rcviov[0].iov_base = (caddr_t)packet;
628 	rcviov[0].iov_len = sizeof(packet);
629 	rcvmhdr.msg_name = (caddr_t)&Rcv;
630 	rcvmhdr.msg_namelen = sizeof(Rcv);
631 	rcvmhdr.msg_iov = rcviov;
632 	rcvmhdr.msg_iovlen = 1;
633 	rcvcmsglen = CMSG_SPACE(sizeof(struct in6_pktinfo)) +
634 	    CMSG_SPACE(sizeof(int));
635 	if ((rcvcmsgbuf = malloc(rcvcmsglen)) == NULL) {
636 		fprintf(stderr, "traceroute6: malloc failed\n");
637 		exit(1);
638 	}
639 	rcvmhdr.msg_control = (caddr_t) rcvcmsgbuf;
640 	rcvmhdr.msg_controllen = rcvcmsglen;
641 
642 	if (options & SO_DEBUG)
643 		(void) setsockopt(rcvsock, SOL_SOCKET, SO_DEBUG,
644 		    (char *)&on, sizeof(on));
645 	if (options & SO_DONTROUTE)
646 		(void) setsockopt(rcvsock, SOL_SOCKET, SO_DONTROUTE,
647 		    (char *)&on, sizeof(on));
648 #ifdef IPSEC
649 #ifdef IPSEC_POLICY_IPSEC
650 	/*
651 	 * do not raise error even if setsockopt fails, kernel may have ipsec
652 	 * turned off.
653 	 */
654 	if (setpolicy(rcvsock, "in bypass") < 0)
655 		errx(1, "%s", ipsec_strerror());
656 	if (setpolicy(rcvsock, "out bypass") < 0)
657 		errx(1, "%s", ipsec_strerror());
658 #else
659     {
660 	int level = IPSEC_LEVEL_NONE;
661 
662 	(void)setsockopt(rcvsock, IPPROTO_IPV6, IPV6_ESP_TRANS_LEVEL, &level,
663 	    sizeof(level));
664 	(void)setsockopt(rcvsock, IPPROTO_IPV6, IPV6_ESP_NETWORK_LEVEL, &level,
665 	    sizeof(level));
666 #ifdef IP_AUTH_TRANS_LEVEL
667 	(void)setsockopt(rcvsock, IPPROTO_IPV6, IPV6_AUTH_TRANS_LEVEL, &level,
668 	    sizeof(level));
669 #else
670 	(void)setsockopt(rcvsock, IPPROTO_IPV6, IPV6_AUTH_LEVEL, &level,
671 	    sizeof(level));
672 #endif
673 #ifdef IP_AUTH_NETWORK_LEVEL
674 	(void)setsockopt(rcvsock, IPPROTO_IPV6, IPV6_AUTH_NETWORK_LEVEL, &level,
675 	    sizeof(level));
676 #endif
677     }
678 #endif /*IPSEC_POLICY_IPSEC*/
679 #endif /*IPSEC*/
680 
681 	/*
682 	 * Send UDP or ICMP
683 	 */
684 	if (useicmp) {
685 		sndsock = rcvsock;
686 	} else {
687 		if ((sndsock = socket(AF_INET6, SOCK_DGRAM, 0)) < 0) {
688 			perror("socket(SOCK_DGRAM)");
689 			exit(5);
690 		}
691 	}
692 #ifdef SO_SNDBUF
693 	i = datalen;
694 	if (setsockopt(sndsock, SOL_SOCKET, SO_SNDBUF, (char *)&i,
695 	    sizeof(i)) < 0) {
696 		perror("setsockopt(SO_SNDBUF)");
697 		exit(6);
698 	}
699 #endif /* SO_SNDBUF */
700 	if (options & SO_DEBUG)
701 		(void) setsockopt(sndsock, SOL_SOCKET, SO_DEBUG,
702 		    (char *)&on, sizeof(on));
703 	if (options & SO_DONTROUTE)
704 		(void) setsockopt(sndsock, SOL_SOCKET, SO_DONTROUTE,
705 		    (char *)&on, sizeof(on));
706 #ifdef USE_RFC2292BIS
707 	if (rth) {/* XXX: there is no library to finalize the header... */
708 		rth->ip6r_len = rth->ip6r_segleft * 2;
709 		if (setsockopt(sndsock, IPPROTO_IPV6, IPV6_RTHDR,
710 		    (void *)rth, (rth->ip6r_len + 1) << 3)) {
711 			fprintf(stderr, "setsockopt(IPV6_RTHDR): %s\n",
712 			    strerror(errno));
713 			exit(1);
714 		}
715 	}
716 #else  /* old advanced API */
717 	if (cmsg != NULL) {
718 		inet6_rthdr_lasthop(cmsg, IPV6_RTHDR_LOOSE);
719 		if (setsockopt(sndsock, IPPROTO_IPV6, IPV6_PKTOPTIONS,
720 		    rtbuf, cmsg->cmsg_len) < 0) {
721 			fprintf(stderr, "setsockopt(IPV6_PKTOPTIONS): %s\n",
722 			    strerror(errno));
723 			exit(1);
724 		}
725 	}
726 #endif /* USE_RFC2292BIS */
727 #ifdef IPSEC
728 #ifdef IPSEC_POLICY_IPSEC
729 	/*
730 	 * do not raise error even if setsockopt fails, kernel may have ipsec
731 	 * turned off.
732 	 */
733 	if (setpolicy(sndsock, "in bypass") < 0)
734 		errx(1, "%s", ipsec_strerror());
735 	if (setpolicy(sndsock, "out bypass") < 0)
736 		errx(1, "%s", ipsec_strerror());
737 #else
738     {
739 	int level = IPSEC_LEVEL_BYPASS;
740 
741 	(void)setsockopt(sndsock, IPPROTO_IPV6, IPV6_ESP_TRANS_LEVEL, &level,
742 	    sizeof(level));
743 	(void)setsockopt(sndsock, IPPROTO_IPV6, IPV6_ESP_NETWORK_LEVEL, &level,
744 	    sizeof(level));
745 #ifdef IP_AUTH_TRANS_LEVEL
746 	(void)setsockopt(sndsock, IPPROTO_IPV6, IPV6_AUTH_TRANS_LEVEL, &level,
747 	    sizeof(level));
748 #else
749 	(void)setsockopt(sndsock, IPPROTO_IPV6, IPV6_AUTH_LEVEL, &level,
750 	    sizeof(level));
751 #endif
752 #ifdef IP_AUTH_NETWORK_LEVEL
753 	(void)setsockopt(sndsock, IPPROTO_IPV6, IPV6_AUTH_NETWORK_LEVEL, &level,
754 	    sizeof(level));
755 #endif
756     }
757 #endif /*IPSEC_POLICY_IPSEC*/
758 #endif /*IPSEC*/
759 
760 	/*
761 	 * Source selection
762 	 */
763 	bzero(&Src, sizeof(Src));
764 	if (source) {
765 		struct addrinfo hints, *res;
766 		int error;
767 
768 		memset(&hints, 0, sizeof(hints));
769 		hints.ai_family = AF_INET6;
770 		hints.ai_socktype = SOCK_DGRAM;	/*dummy*/
771 		hints.ai_flags = AI_NUMERICHOST;
772 		error = getaddrinfo(source, "0", &hints, &res);
773 		if (error) {
774 			printf("traceroute6: %s: %s\n", source,
775 			    gai_strerror(error));
776 			exit(1);
777 		}
778 		if (res->ai_addrlen > sizeof(Src)) {
779 			printf("traceroute6: %s: %s\n", source,
780 			    gai_strerror(error));
781 			exit(1);
782 		}
783 		memcpy(&Src, res->ai_addr, res->ai_addrlen);
784 		freeaddrinfo(res);
785 	} else {
786 		struct sockaddr_in6 Nxt;
787 		int dummy;
788 		socklen_t len;
789 
790 		Nxt = Dst;
791 		Nxt.sin6_port = htons(DUMMY_PORT);
792 		if (cmsg != NULL)
793 			bcopy(inet6_rthdr_getaddr(cmsg, 1), &Nxt.sin6_addr,
794 			    sizeof(Nxt.sin6_addr));
795 		if ((dummy = socket(AF_INET6, SOCK_DGRAM, 0)) < 0) {
796 			perror("socket");
797 			exit(1);
798 		}
799 		if (connect(dummy, (struct sockaddr *)&Nxt, Nxt.sin6_len) < 0) {
800 			perror("connect");
801 			exit(1);
802 		}
803 		len = sizeof(Src);
804 		if (getsockname(dummy, (struct sockaddr *)&Src, &len) < 0) {
805 			perror("getsockname");
806 			exit(1);
807 		}
808 		if (getnameinfo((struct sockaddr *)&Src, Src.sin6_len,
809 		    src0, sizeof(src0), NULL, 0, NI_NUMERICHOST)) {
810 			fprintf(stderr, "getnameinfo failed for source\n");
811 			exit(1);
812 		}
813 		source = src0;
814 		close(dummy);
815 	}
816 
817 	Src.sin6_port = htons(0);
818 	if (bind(sndsock, (struct sockaddr *)&Src, Src.sin6_len) < 0) {
819 		perror("bind");
820 		exit(1);
821 	}
822 
823 	{
824 		socklen_t len;
825 
826 		len = sizeof(Src);
827 		if (getsockname(sndsock, (struct sockaddr *)&Src, &len) < 0) {
828 			perror("getsockname");
829 			exit(1);
830 		}
831 		srcport = ntohs(Src.sin6_port);
832 	}
833 
834 	/*
835 	 * Message to users
836 	 */
837 	if (getnameinfo((struct sockaddr *)&Dst, Dst.sin6_len, hbuf,
838 	    sizeof(hbuf), NULL, 0, NI_NUMERICHOST))
839 		strlcpy(hbuf, "(invalid)", sizeof(hbuf));
840 	fprintf(stderr, "traceroute6");
841 	fprintf(stderr, " to %s (%s)", hostname, hbuf);
842 	if (source)
843 		fprintf(stderr, " from %s", source);
844 	fprintf(stderr, ", %lu hops max, %lu byte packets\n",
845 	    max_hops, datalen);
846 	(void) fflush(stderr);
847 
848 	if (first_hop > 1)
849 		printf("Skipping %lu intermediate hops\n", first_hop - 1);
850 
851 	/*
852 	 * Main loop
853 	 */
854 	for (hops = first_hop; hops <= max_hops; ++hops) {
855 		struct in6_addr lastaddr;
856 		int got_there = 0;
857 		int unreachable = 0;
858 
859 		printf("%2lu ", hops);
860 		bzero(&lastaddr, sizeof(lastaddr));
861 		for (probe = 0; probe < nprobes; ++probe) {
862 			int cc;
863 			struct timeval t1, t2;
864 
865 			(void) gettimeofday(&t1, NULL);
866 			send_probe(++seq, hops);
867 			while ((cc = wait_for_reply(rcvsock, &rcvmhdr))) {
868 				(void) gettimeofday(&t2, NULL);
869 				if ((i = packet_ok(&rcvmhdr, cc, seq))) {
870 					if (!IN6_ARE_ADDR_EQUAL(&Rcv.sin6_addr,
871 					    &lastaddr)) {
872 						print(&rcvmhdr, cc);
873 						lastaddr = Rcv.sin6_addr;
874 					}
875 					printf("  %.3f ms", deltaT(&t1, &t2));
876 					switch (i - 1) {
877 					case ICMP6_DST_UNREACH_NOROUTE:
878 						++unreachable;
879 						printf(" !N");
880 						break;
881 					case ICMP6_DST_UNREACH_ADMIN:
882 						++unreachable;
883 						printf(" !P");
884 						break;
885 					case ICMP6_DST_UNREACH_NOTNEIGHBOR:
886 						++unreachable;
887 						printf(" !S");
888 						break;
889 					case ICMP6_DST_UNREACH_ADDR:
890 						++unreachable;
891 						printf(" !A");
892 						break;
893 					case ICMP6_DST_UNREACH_NOPORT:
894 						if (rcvhlim >= 0 &&
895 						    rcvhlim <= 1)
896 							printf(" !");
897 						++got_there;
898 						break;
899 					}
900 					break;
901 				}
902 			}
903 			if (cc == 0)
904 				printf(" *");
905 			(void) fflush(stdout);
906 		}
907 		putchar('\n');
908 		if (got_there ||
909 		    (unreachable > 0 && unreachable >= ((nprobes + 1) / 2))) {
910 			exit(0);
911 		}
912 	}
913 
914 	exit(0);
915 }
916 
917 int
918 wait_for_reply(sock, mhdr)
919 	int sock;
920 	struct msghdr *mhdr;
921 {
922 #ifdef HAVE_POLL
923 	struct pollfd pfd[1];
924 	int cc = 0;
925 
926 	pfd[0].fd = sock;
927 	pfd[0].events = POLLIN;
928 	pfd[0].revents = 0;
929 
930 	if (poll(pfd, 1, waittime * 1000) > 0)
931 		cc = recvmsg(rcvsock, mhdr, 0);
932 
933 	return(cc);
934 #else
935 	fd_set *fdsp;
936 	struct timeval wait;
937 	int cc = 0, fdsn;
938 
939 	fdsn = howmany(sock + 1, NFDBITS) * sizeof(fd_mask);
940 	if ((fdsp = (fd_set *)malloc(fdsn)) == NULL)
941 		err(1, "malloc");
942 	memset(fdsp, 0, fdsn);
943 	FD_SET(sock, fdsp);
944 	wait.tv_sec = waittime; wait.tv_usec = 0;
945 
946 	if (select(sock+1, fdsp, (fd_set *)0, (fd_set *)0, &wait) > 0)
947 		cc = recvmsg(rcvsock, mhdr, 0);
948 
949 	free(fdsp);
950 	return(cc);
951 #endif
952 }
953 
954 #ifdef IPSEC
955 #ifdef IPSEC_POLICY_IPSEC
956 int
957 setpolicy(so, policy)
958 	int so;
959 	char *policy;
960 {
961 	char *buf;
962 
963 	buf = ipsec_set_policy(policy, strlen(policy));
964 	if (buf == NULL) {
965 		warnx("%s", ipsec_strerror());
966 		return -1;
967 	}
968 	(void)setsockopt(so, IPPROTO_IPV6, IPV6_IPSEC_POLICY,
969 	    buf, ipsec_get_policylen(buf));
970 
971 	free(buf);
972 
973 	return 0;
974 }
975 #endif
976 #endif
977 
978 void
979 send_probe(seq, hops)
980 	int seq;
981 	u_long hops;
982 {
983 	struct timeval tv;
984 	struct tv32 tv32;
985 	int i;
986 
987 	i = hops;
988 	if (setsockopt(sndsock, IPPROTO_IPV6, IPV6_UNICAST_HOPS,
989 	    (char *)&i, sizeof(i)) < 0) {
990 		perror("setsockopt IPV6_UNICAST_HOPS");
991 	}
992 
993 	Dst.sin6_port = htons(port + seq);
994 	(void) gettimeofday(&tv, NULL);
995 	tv32.tv32_sec = htonl(tv.tv_sec);
996 	tv32.tv32_usec = htonl(tv.tv_usec);
997 
998 	if (useicmp) {
999 		struct icmp6_hdr *icp = (struct icmp6_hdr *)outpacket;
1000 
1001 		icp->icmp6_type = ICMP6_ECHO_REQUEST;
1002 		icp->icmp6_code = 0;
1003 		icp->icmp6_cksum = 0;
1004 		icp->icmp6_id = ident;
1005 		icp->icmp6_seq = htons(seq);
1006 		bcopy(&tv32, ((u_int8_t *)outpacket + ICMP6ECHOLEN),
1007 		    sizeof(tv32));
1008 	} else {
1009 		struct opacket *op = outpacket;
1010 
1011 		op->seq = seq;
1012 		op->hops = hops;
1013 		bcopy(&tv32, &op->tv, sizeof tv32);
1014 	}
1015 
1016 	i = sendto(sndsock, (char *)outpacket, datalen, 0,
1017 	    (struct sockaddr *)&Dst, Dst.sin6_len);
1018 	if (i < 0 || i != datalen)  {
1019 		if (i < 0)
1020 			perror("sendto");
1021 		printf("traceroute6: wrote %s %lu chars, ret=%d\n",
1022 		    hostname, datalen, i);
1023 		(void) fflush(stdout);
1024 	}
1025 }
1026 
1027 int
1028 get_hoplim(mhdr)
1029 	struct msghdr *mhdr;
1030 {
1031 	struct cmsghdr *cm;
1032 
1033 	for (cm = (struct cmsghdr *)CMSG_FIRSTHDR(mhdr); cm;
1034 	    cm = (struct cmsghdr *)CMSG_NXTHDR(mhdr, cm)) {
1035 		if (cm->cmsg_level == IPPROTO_IPV6 &&
1036 		    cm->cmsg_type == IPV6_HOPLIMIT &&
1037 		    cm->cmsg_len == CMSG_LEN(sizeof(int)))
1038 			return(*(int *)CMSG_DATA(cm));
1039 	}
1040 
1041 	return(-1);
1042 }
1043 
1044 double
1045 deltaT(t1p, t2p)
1046 	struct timeval *t1p, *t2p;
1047 {
1048 	double dt;
1049 
1050 	dt = (double)(t2p->tv_sec - t1p->tv_sec) * 1000.0 +
1051 	    (double)(t2p->tv_usec - t1p->tv_usec) / 1000.0;
1052 	return (dt);
1053 }
1054 
1055 /*
1056  * Convert an ICMP "type" field to a printable string.
1057  */
1058 char *
1059 pr_type(t0)
1060 	int t0;
1061 {
1062 	u_char t = t0 & 0xff;
1063 	char *cp;
1064 
1065 	switch (t) {
1066 	case ICMP6_DST_UNREACH:
1067 		cp = "Destination Unreachable";
1068 		break;
1069 	case ICMP6_PACKET_TOO_BIG:
1070 		cp = "Packet Too Big";
1071 		break;
1072 	case ICMP6_TIME_EXCEEDED:
1073 		cp = "Time Exceeded";
1074 		break;
1075 	case ICMP6_PARAM_PROB:
1076 		cp = "Parameter Problem";
1077 		break;
1078 	case ICMP6_ECHO_REQUEST:
1079 		cp = "Echo Request";
1080 		break;
1081 	case ICMP6_ECHO_REPLY:
1082 		cp = "Echo Reply";
1083 		break;
1084 	case ICMP6_MEMBERSHIP_QUERY:
1085 		cp = "Group Membership Query";
1086 		break;
1087 	case ICMP6_MEMBERSHIP_REPORT:
1088 		cp = "Group Membership Report";
1089 		break;
1090 	case ICMP6_MEMBERSHIP_REDUCTION:
1091 		cp = "Group Membership Reduction";
1092 		break;
1093 	case ND_ROUTER_SOLICIT:
1094 		cp = "Router Solicitation";
1095 		break;
1096 	case ND_ROUTER_ADVERT:
1097 		cp = "Router Advertisement";
1098 		break;
1099 	case ND_NEIGHBOR_SOLICIT:
1100 		cp = "Neighbor Solicitation";
1101 		break;
1102 	case ND_NEIGHBOR_ADVERT:
1103 		cp = "Neighbor Advertisement";
1104 		break;
1105 	case ND_REDIRECT:
1106 		cp = "Redirect";
1107 		break;
1108 	default:
1109 		cp = "Unknown";
1110 		break;
1111 	}
1112 	return cp;
1113 }
1114 
1115 int
1116 packet_ok(mhdr, cc, seq)
1117 	struct msghdr *mhdr;
1118 	int cc;
1119 	int seq;
1120 {
1121 	struct icmp6_hdr *icp;
1122 	struct sockaddr_in6 *from = (struct sockaddr_in6 *)mhdr->msg_name;
1123 	u_char type, code;
1124 	char *buf = (char *)mhdr->msg_iov[0].iov_base;
1125 	struct cmsghdr *cm;
1126 	int *hlimp;
1127 	char hbuf[NI_MAXHOST];
1128 
1129 #ifdef OLDRAWSOCKET
1130 	int hlen;
1131 	struct ip6_hdr *ip;
1132 #endif
1133 
1134 #ifdef OLDRAWSOCKET
1135 	ip = (struct ip6_hdr *) buf;
1136 	hlen = sizeof(struct ip6_hdr);
1137 	if (cc < hlen + sizeof(struct icmp6_hdr)) {
1138 		if (verbose) {
1139 			if (getnameinfo((struct sockaddr *)from, from->sin6_len,
1140 			    hbuf, sizeof(hbuf), NULL, 0, NI_NUMERICHOST) != 0)
1141 				strlcpy(hbuf, "invalid", sizeof(hbuf));
1142 			printf("packet too short (%d bytes) from %s\n", cc,
1143 			    hbuf);
1144 		}
1145 		return (0);
1146 	}
1147 	cc -= hlen;
1148 	icp = (struct icmp6_hdr *)(buf + hlen);
1149 #else
1150 	if (cc < sizeof(struct icmp6_hdr)) {
1151 		if (verbose) {
1152 			if (getnameinfo((struct sockaddr *)from, from->sin6_len,
1153 			    hbuf, sizeof(hbuf), NULL, 0, NI_NUMERICHOST) != 0)
1154 				strlcpy(hbuf, "invalid", sizeof(hbuf));
1155 			printf("data too short (%d bytes) from %s\n", cc, hbuf);
1156 		}
1157 		return(0);
1158 	}
1159 	icp = (struct icmp6_hdr *)buf;
1160 #endif
1161 	/* get optional information via advanced API */
1162 	rcvpktinfo = NULL;
1163 	hlimp = NULL;
1164 	for (cm = (struct cmsghdr *)CMSG_FIRSTHDR(mhdr); cm;
1165 	    cm = (struct cmsghdr *)CMSG_NXTHDR(mhdr, cm)) {
1166 		if (cm->cmsg_level == IPPROTO_IPV6 &&
1167 		    cm->cmsg_type == IPV6_PKTINFO &&
1168 		    cm->cmsg_len ==
1169 		    CMSG_LEN(sizeof(struct in6_pktinfo)))
1170 			rcvpktinfo = (struct in6_pktinfo *)(CMSG_DATA(cm));
1171 
1172 		if (cm->cmsg_level == IPPROTO_IPV6 &&
1173 		    cm->cmsg_type == IPV6_HOPLIMIT &&
1174 		    cm->cmsg_len == CMSG_LEN(sizeof(int)))
1175 			hlimp = (int *)CMSG_DATA(cm);
1176 	}
1177 	if (rcvpktinfo == NULL || hlimp == NULL) {
1178 		warnx("failed to get received hop limit or packet info");
1179 #if 0
1180 		return(0);
1181 #else
1182 		rcvhlim = 0;	/*XXX*/
1183 #endif
1184 	}
1185 	else
1186 		rcvhlim = *hlimp;
1187 
1188 	type = icp->icmp6_type;
1189 	code = icp->icmp6_code;
1190 	if ((type == ICMP6_TIME_EXCEEDED && code == ICMP6_TIME_EXCEED_TRANSIT)
1191 	    || type == ICMP6_DST_UNREACH) {
1192 		struct ip6_hdr *hip;
1193 		struct udphdr *up;
1194 
1195 		hip = (struct ip6_hdr *)(icp + 1);
1196 		if ((up = get_udphdr(hip, (u_char *)(buf + cc))) == NULL) {
1197 			if (verbose)
1198 				warnx("failed to get upper layer header");
1199 			return(0);
1200 		}
1201 		if (useicmp &&
1202 		    ((struct icmp6_hdr *)up)->icmp6_id == ident &&
1203 		    ((struct icmp6_hdr *)up)->icmp6_seq == htons(seq))
1204 			return (type == ICMP6_TIME_EXCEEDED ? -1 : code + 1);
1205 		else if (!useicmp &&
1206 		    up->uh_sport == htons(srcport) &&
1207 		    up->uh_dport == htons(port + seq))
1208 			return (type == ICMP6_TIME_EXCEEDED ? -1 : code + 1);
1209 	} else if (useicmp && type == ICMP6_ECHO_REPLY) {
1210 		if (icp->icmp6_id == ident &&
1211 		    icp->icmp6_seq == htons(seq))
1212 			return (ICMP6_DST_UNREACH_NOPORT + 1);
1213 	}
1214 	if (verbose) {
1215 		char sbuf[NI_MAXHOST+1], dbuf[INET6_ADDRSTRLEN];
1216 		u_int8_t *p;
1217 		int i;
1218 
1219 		if (getnameinfo((struct sockaddr *)from, from->sin6_len,
1220 		    sbuf, sizeof(sbuf), NULL, 0, NI_NUMERICHOST) != 0)
1221 			strlcpy(sbuf, "invalid", sizeof(sbuf));
1222 		printf("\n%d bytes from %s to %s", cc, sbuf,
1223 		    rcvpktinfo ? inet_ntop(AF_INET6, &rcvpktinfo->ipi6_addr,
1224 		    dbuf, sizeof(dbuf)) : "?");
1225 		printf(": icmp type %d (%s) code %d\n", type, pr_type(type),
1226 		    icp->icmp6_code);
1227 		p = (u_int8_t *)(icp + 1);
1228 #define WIDTH	16
1229 		for (i = 0; i < cc; i++) {
1230 			if (i % WIDTH == 0)
1231 				printf("%04x:", i);
1232 			if (i % 4 == 0)
1233 				printf(" ");
1234 			printf("%02x", p[i]);
1235 			if (i % WIDTH == WIDTH - 1)
1236 				printf("\n");
1237 		}
1238 		if (cc % WIDTH != 0)
1239 			printf("\n");
1240 	}
1241 	return(0);
1242 }
1243 
1244 /*
1245  * Increment pointer until find the UDP or ICMP header.
1246  */
1247 struct udphdr *
1248 get_udphdr(ip6, lim)
1249 	struct ip6_hdr *ip6;
1250 	u_char *lim;
1251 {
1252 	u_char *cp = (u_char *)ip6, nh;
1253 	int hlen;
1254 
1255 	if (cp + sizeof(*ip6) >= lim)
1256 		return(NULL);
1257 
1258 	nh = ip6->ip6_nxt;
1259 	cp += sizeof(struct ip6_hdr);
1260 
1261 	while (lim - cp >= 8) {
1262 		switch (nh) {
1263 		case IPPROTO_ESP:
1264 		case IPPROTO_TCP:
1265 			return(NULL);
1266 		case IPPROTO_ICMPV6:
1267 			return(useicmp ? (struct udphdr *)cp : NULL);
1268 		case IPPROTO_UDP:
1269 			return(useicmp ? NULL : (struct udphdr *)cp);
1270 		case IPPROTO_FRAGMENT:
1271 			hlen = sizeof(struct ip6_frag);
1272 			nh = ((struct ip6_frag *)cp)->ip6f_nxt;
1273 			break;
1274 		case IPPROTO_AH:
1275 			hlen = (((struct ip6_ext *)cp)->ip6e_len + 2) << 2;
1276 			nh = ((struct ip6_ext *)cp)->ip6e_nxt;
1277 			break;
1278 		default:
1279 			hlen = (((struct ip6_ext *)cp)->ip6e_len + 1) << 3;
1280 			nh = ((struct ip6_ext *)cp)->ip6e_nxt;
1281 			break;
1282 		}
1283 
1284 		cp += hlen;
1285 	}
1286 
1287 	return(NULL);
1288 }
1289 
1290 void
1291 print(mhdr, cc)
1292 	struct msghdr *mhdr;
1293 	int cc;
1294 {
1295 	struct sockaddr_in6 *from = (struct sockaddr_in6 *)mhdr->msg_name;
1296 	char hbuf[NI_MAXHOST];
1297 
1298 	if (getnameinfo((struct sockaddr *)from, from->sin6_len,
1299 	    hbuf, sizeof(hbuf), NULL, 0, NI_NUMERICHOST) != 0)
1300 		strlcpy(hbuf, "invalid", sizeof(hbuf));
1301 	if (nflag)
1302 		printf(" %s", hbuf);
1303 	else if (lflag)
1304 		printf(" %s (%s)", inetname((struct sockaddr *)from), hbuf);
1305 	else
1306 		printf(" %s", inetname((struct sockaddr *)from));
1307 
1308 	if (verbose) {
1309 #ifdef OLDRAWSOCKET
1310 		printf(" %d bytes to %s", cc,
1311 		    rcvpktinfo ? inet_ntop(AF_INET6, &rcvpktinfo->ipi6_addr,
1312 		    hbuf, sizeof(hbuf)) : "?");
1313 #else
1314 		printf(" %d bytes of data to %s", cc,
1315 		    rcvpktinfo ?  inet_ntop(AF_INET6, &rcvpktinfo->ipi6_addr,
1316 		    hbuf, sizeof(hbuf)) : "?");
1317 #endif
1318 	}
1319 }
1320 
1321 /*
1322  * Construct an Internet address representation.
1323  * If the nflag has been supplied, give
1324  * numeric value, otherwise try for symbolic name.
1325  */
1326 const char *
1327 inetname(sa)
1328 	struct sockaddr *sa;
1329 {
1330 	static char line[NI_MAXHOST], domain[MAXHOSTNAMELEN + 1];
1331 	static int first = 1;
1332 	char *cp;
1333 
1334 	if (first && !nflag) {
1335 		first = 0;
1336 		if (gethostname(domain, sizeof(domain)) == 0 &&
1337 		    (cp = strchr(domain, '.')))
1338 			(void) strlcpy(domain, cp + 1, sizeof(domain));
1339 		else
1340 			domain[0] = 0;
1341 	}
1342 	cp = NULL;
1343 	if (!nflag) {
1344 		if (getnameinfo(sa, sa->sa_len, line, sizeof(line), NULL, 0,
1345 		    NI_NAMEREQD) == 0) {
1346 			if ((cp = strchr(line, '.')) &&
1347 			    !strcmp(cp + 1, domain))
1348 				*cp = 0;
1349 			cp = line;
1350 		}
1351 	}
1352 	if (cp)
1353 		return cp;
1354 
1355 	if (getnameinfo(sa, sa->sa_len, line, sizeof(line), NULL, 0,
1356 	    NI_NUMERICHOST) != 0)
1357 		strlcpy(line, "invalid", sizeof(line));
1358 	return line;
1359 }
1360 
1361 void
1362 usage()
1363 {
1364 
1365 	fprintf(stderr,
1366 "usage: traceroute6 [-dIlnrv] [-f firsthop] [-g gateway] [-m hoplimit]\n"
1367 "       [-p port] [-q probes] [-s src] [-w waittime] target [datalen]\n");
1368 	exit(1);
1369 }
1370