xref: /netbsd-src/usr.sbin/traceroute6/traceroute6.c (revision b1c86f5f087524e68db12794ee9c3e3da1ab17a0)
1 /*	$NetBSD: traceroute6.c,v 1.39 2010/05/13 18:19:18 christos Exp $	*/
2 /*	$KAME: traceroute6.c,v 1.67 2004/01/25 03:24:39 itojun Exp $	*/
3 
4 /*
5  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. Neither the name of the project nor the names of its contributors
17  *    may be used to endorse or promote products derived from this software
18  *    without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  */
32 
33 /*-
34  * Copyright (c) 1990, 1993
35  *	The Regents of the University of California.  All rights reserved.
36  *
37  * This code is derived from software contributed to Berkeley by
38  * Van Jacobson.
39  *
40  * Redistribution and use in source and binary forms, with or without
41  * modification, are permitted provided that the following conditions
42  * are met:
43  * 1. Redistributions of source code must retain the above copyright
44  *    notice, this list of conditions and the following disclaimer.
45  * 2. Redistributions in binary form must reproduce the above copyright
46  *    notice, this list of conditions and the following disclaimer in the
47  *    documentation and/or other materials provided with the distribution.
48  * 3. Neither the name of the University nor the names of its contributors
49  *    may be used to endorse or promote products derived from this software
50  *    without specific prior written permission.
51  *
52  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
53  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
54  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
55  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
56  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
57  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
58  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
59  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
60  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
61  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
62  * SUCH DAMAGE.
63  */
64 
65 #if 0
66 #ifndef lint
67 static char copyright[] =
68 "@(#) Copyright (c) 1990, 1993\n\
69 	The Regents of the University of California.  All rights reserved.\n";
70 #endif /* not lint */
71 
72 #ifndef lint
73 static char sccsid[] = "@(#)traceroute.c	8.1 (Berkeley) 6/6/93";
74 #endif /* not lint */
75 #else
76 #include <sys/cdefs.h>
77 #ifndef lint
78 __RCSID("$NetBSD: traceroute6.c,v 1.39 2010/05/13 18:19:18 christos Exp $");
79 #endif
80 #endif
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 #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 } __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_RFC3542
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_RFC3542
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 			/* same as ping6 */
471 			ident = htons(arc4random() & 0xffff);
472 			break;
473 		case 'l':
474 			lflag++;
475 			break;
476 		case 'm':
477 			ep = NULL;
478 			errno = 0;
479 			max_hops = strtoul(optarg, &ep, 0);
480 			if (errno || !*optarg || *ep || max_hops > 255) {
481 				fprintf(stderr,
482 				    "traceroute6: invalid max hoplimit.\n");
483 				exit(1);
484 			}
485 			break;
486 		case 'n':
487 			nflag++;
488 			break;
489 		case 'p':
490 			ep = NULL;
491 			errno = 0;
492 			lport = strtoul(optarg, &ep, 0);
493 			if (errno || !*optarg || *ep) {
494 				fprintf(stderr, "traceroute6: invalid port.\n");
495 				exit(1);
496 			}
497 			if (lport == 0 || lport != (lport & 0xffff)) {
498 				fprintf(stderr,
499 				    "traceroute6: port out of range.\n");
500 				exit(1);
501 			}
502 			port = lport & 0xffff;
503 			break;
504 		case 'q':
505 			ep = NULL;
506 			errno = 0;
507 			nprobes = strtoul(optarg, &ep, 0);
508 			if (errno || !*optarg || *ep) {
509 				fprintf(stderr,
510 				    "traceroute6: invalid nprobes.\n");
511 				exit(1);
512 			}
513 			if (nprobes < 1) {
514 				fprintf(stderr,
515 				    "traceroute6: nprobes must be >0.\n");
516 				exit(1);
517 			}
518 			break;
519 		case 'r':
520 			options |= SO_DONTROUTE;
521 			break;
522 		case 's':
523 			/*
524 			 * set the ip source address of the outbound
525 			 * probe (e.g., on a multi-homed host).
526 			 */
527 			source = optarg;
528 			break;
529 		case 'v':
530 			verbose++;
531 			break;
532 		case 'w':
533 			ep = NULL;
534 			errno = 0;
535 			waittime = strtoul(optarg, &ep, 0);
536 			if (errno || !*optarg || *ep) {
537 				fprintf(stderr,
538 				    "traceroute6: invalid wait time.\n");
539 				exit(1);
540 			}
541 			if (waittime <= 1) {
542 				fprintf(stderr,
543 				    "traceroute6: wait must be >1 sec.\n");
544 				exit(1);
545 			}
546 			break;
547 		default:
548 			usage();
549 		}
550 	argc -= optind;
551 	argv += optind;
552 
553 	if (max_hops < first_hop) {
554 		fprintf(stderr,
555 		    "traceroute6: max hoplimit must be larger than first hoplimit.\n");
556 		exit(1);
557 	}
558 
559 	if (argc < 1 || argc > 2)
560 		usage();
561 
562 #if 1
563 	setvbuf(stdout, NULL, _IOLBF, BUFSIZ);
564 #else
565 	setlinebuf(stdout);
566 #endif
567 
568 	memset(&hints, 0, sizeof(hints));
569 	hints.ai_family = PF_INET6;
570 	hints.ai_socktype = SOCK_RAW;
571 	hints.ai_protocol = IPPROTO_ICMPV6;
572 	hints.ai_flags = AI_CANONNAME;
573 	error = getaddrinfo(*argv, NULL, &hints, &res);
574 	if (error) {
575 		fprintf(stderr,
576 		    "traceroute6: %s\n", gai_strerror(error));
577 		exit(1);
578 	}
579 	if (res->ai_addrlen != sizeof(Dst)) {
580 		fprintf(stderr,
581 		    "traceroute6: size of sockaddr mismatch\n");
582 		exit(1);
583 	}
584 	memcpy(&Dst, res->ai_addr, res->ai_addrlen);
585 	hostname = res->ai_canonname ? strdup(res->ai_canonname) : *argv;
586 	if (!hostname) {
587 		fprintf(stderr, "traceroute6: not enough core\n");
588 		exit(1);
589 	}
590 	if (res->ai_next) {
591 		if (getnameinfo(res->ai_addr, res->ai_addrlen, hbuf,
592 		    sizeof(hbuf), NULL, 0, NI_NUMERICHOST) != 0)
593 			strlcpy(hbuf, "?", sizeof(hbuf));
594 		fprintf(stderr, "traceroute6: Warning: %s has multiple "
595 		    "addresses; using %s\n", hostname, hbuf);
596 	}
597 
598 	if (*++argv) {
599 		ep = NULL;
600 		errno = 0;
601 		datalen = strtoul(*argv, &ep, 0);
602 		if (errno || !*argv || *ep) {
603 			fprintf(stderr,
604 			    "traceroute6: invalid packet length.\n");
605 			exit(1);
606 		}
607 	}
608 	if (useicmp)
609 		minlen = ICMP6ECHOLEN + sizeof(struct tv32);
610 	else
611 		minlen = sizeof(struct opacket);
612 	if (datalen < minlen)
613 		datalen = minlen;
614 	else if (datalen >= MAXPACKET) {
615 		fprintf(stderr,
616 		    "traceroute6: packet size must be %d <= s < %ld.\n",
617 		    minlen, (long)MAXPACKET);
618 		exit(1);
619 	}
620 	outpacket = (struct opacket *)malloc((unsigned)datalen);
621 	if (!outpacket) {
622 		perror("malloc");
623 		exit(1);
624 	}
625 	(void) bzero((char *)outpacket, datalen);
626 
627 	/* initialize msghdr for receiving packets */
628 	rcviov[0].iov_base = (caddr_t)packet;
629 	rcviov[0].iov_len = sizeof(packet);
630 	rcvmhdr.msg_name = (caddr_t)&Rcv;
631 	rcvmhdr.msg_namelen = sizeof(Rcv);
632 	rcvmhdr.msg_iov = rcviov;
633 	rcvmhdr.msg_iovlen = 1;
634 	rcvcmsglen = CMSG_SPACE(sizeof(struct in6_pktinfo)) +
635 	    CMSG_SPACE(sizeof(int));
636 	if ((rcvcmsgbuf = malloc(rcvcmsglen)) == NULL) {
637 		fprintf(stderr, "traceroute6: malloc failed\n");
638 		exit(1);
639 	}
640 	rcvmhdr.msg_control = (caddr_t) rcvcmsgbuf;
641 	rcvmhdr.msg_controllen = rcvcmsglen;
642 
643 	if (options & SO_DEBUG)
644 		(void) setsockopt(rcvsock, SOL_SOCKET, SO_DEBUG,
645 		    (char *)&on, sizeof(on));
646 	if (options & SO_DONTROUTE)
647 		(void) setsockopt(rcvsock, SOL_SOCKET, SO_DONTROUTE,
648 		    (char *)&on, sizeof(on));
649 #ifdef IPSEC
650 #ifdef IPSEC_POLICY_IPSEC
651 	/*
652 	 * do not raise error even if setsockopt fails, kernel may have ipsec
653 	 * turned off.
654 	 */
655 	if (setpolicy(rcvsock, "in bypass") < 0)
656 		errx(1, "%s", ipsec_strerror());
657 	if (setpolicy(rcvsock, "out bypass") < 0)
658 		errx(1, "%s", ipsec_strerror());
659 #else
660     {
661 	int level = IPSEC_LEVEL_NONE;
662 
663 	(void)setsockopt(rcvsock, IPPROTO_IPV6, IPV6_ESP_TRANS_LEVEL, &level,
664 	    sizeof(level));
665 	(void)setsockopt(rcvsock, IPPROTO_IPV6, IPV6_ESP_NETWORK_LEVEL, &level,
666 	    sizeof(level));
667 #ifdef IP_AUTH_TRANS_LEVEL
668 	(void)setsockopt(rcvsock, IPPROTO_IPV6, IPV6_AUTH_TRANS_LEVEL, &level,
669 	    sizeof(level));
670 #else
671 	(void)setsockopt(rcvsock, IPPROTO_IPV6, IPV6_AUTH_LEVEL, &level,
672 	    sizeof(level));
673 #endif
674 #ifdef IP_AUTH_NETWORK_LEVEL
675 	(void)setsockopt(rcvsock, IPPROTO_IPV6, IPV6_AUTH_NETWORK_LEVEL, &level,
676 	    sizeof(level));
677 #endif
678     }
679 #endif /*IPSEC_POLICY_IPSEC*/
680 #endif /*IPSEC*/
681 
682 	/*
683 	 * Send UDP or ICMP
684 	 */
685 	if (useicmp) {
686 		sndsock = rcvsock;
687 	} else {
688 		if ((sndsock = socket(AF_INET6, SOCK_DGRAM, 0)) < 0) {
689 			perror("socket(SOCK_DGRAM)");
690 			exit(5);
691 		}
692 	}
693 #ifdef SO_SNDBUF
694 	i = datalen;
695 	if (setsockopt(sndsock, SOL_SOCKET, SO_SNDBUF, (char *)&i,
696 	    sizeof(i)) < 0) {
697 		perror("setsockopt(SO_SNDBUF)");
698 		exit(6);
699 	}
700 #endif /* SO_SNDBUF */
701 	if (options & SO_DEBUG)
702 		(void) setsockopt(sndsock, SOL_SOCKET, SO_DEBUG,
703 		    (char *)&on, sizeof(on));
704 	if (options & SO_DONTROUTE)
705 		(void) setsockopt(sndsock, SOL_SOCKET, SO_DONTROUTE,
706 		    (char *)&on, sizeof(on));
707 #ifdef USE_RFC3542
708 	if (rth) {/* XXX: there is no library to finalize the header... */
709 		rth->ip6r_len = rth->ip6r_segleft * 2;
710 		if (setsockopt(sndsock, IPPROTO_IPV6, IPV6_RTHDR,
711 		    (void *)rth, (rth->ip6r_len + 1) << 3)) {
712 			fprintf(stderr, "setsockopt(IPV6_RTHDR): %s\n",
713 			    strerror(errno));
714 			exit(1);
715 		}
716 	}
717 #else  /* old advanced API */
718 	if (cmsg != NULL) {
719 		inet6_rthdr_lasthop(cmsg, IPV6_RTHDR_LOOSE);
720 		if (setsockopt(sndsock, IPPROTO_IPV6, IPV6_PKTOPTIONS,
721 		    rtbuf, cmsg->cmsg_len) < 0) {
722 			fprintf(stderr, "setsockopt(IPV6_PKTOPTIONS): %s\n",
723 			    strerror(errno));
724 			exit(1);
725 		}
726 	}
727 #endif /* USE_RFC3542 */
728 #ifdef IPSEC
729 #ifdef IPSEC_POLICY_IPSEC
730 	/*
731 	 * do not raise error even if setsockopt fails, kernel may have ipsec
732 	 * turned off.
733 	 */
734 	if (setpolicy(sndsock, "in bypass") < 0)
735 		errx(1, "%s", ipsec_strerror());
736 	if (setpolicy(sndsock, "out bypass") < 0)
737 		errx(1, "%s", ipsec_strerror());
738 #else
739     {
740 	int level = IPSEC_LEVEL_BYPASS;
741 
742 	(void)setsockopt(sndsock, IPPROTO_IPV6, IPV6_ESP_TRANS_LEVEL, &level,
743 	    sizeof(level));
744 	(void)setsockopt(sndsock, IPPROTO_IPV6, IPV6_ESP_NETWORK_LEVEL, &level,
745 	    sizeof(level));
746 #ifdef IP_AUTH_TRANS_LEVEL
747 	(void)setsockopt(sndsock, IPPROTO_IPV6, IPV6_AUTH_TRANS_LEVEL, &level,
748 	    sizeof(level));
749 #else
750 	(void)setsockopt(sndsock, IPPROTO_IPV6, IPV6_AUTH_LEVEL, &level,
751 	    sizeof(level));
752 #endif
753 #ifdef IP_AUTH_NETWORK_LEVEL
754 	(void)setsockopt(sndsock, IPPROTO_IPV6, IPV6_AUTH_NETWORK_LEVEL, &level,
755 	    sizeof(level));
756 #endif
757     }
758 #endif /*IPSEC_POLICY_IPSEC*/
759 #endif /*IPSEC*/
760 
761 	/*
762 	 * Source selection
763 	 */
764 	bzero(&Src, sizeof(Src));
765 	if (source) {
766 		struct addrinfo hints, *res;
767 		int error;
768 
769 		memset(&hints, 0, sizeof(hints));
770 		hints.ai_family = AF_INET6;
771 		hints.ai_socktype = SOCK_DGRAM;	/*dummy*/
772 		hints.ai_flags = AI_NUMERICHOST;
773 		error = getaddrinfo(source, "0", &hints, &res);
774 		if (error) {
775 			printf("traceroute6: %s: %s\n", source,
776 			    gai_strerror(error));
777 			exit(1);
778 		}
779 		if (res->ai_addrlen > sizeof(Src)) {
780 			printf("traceroute6: %s: %s\n", source,
781 			    gai_strerror(error));
782 			exit(1);
783 		}
784 		memcpy(&Src, res->ai_addr, res->ai_addrlen);
785 		freeaddrinfo(res);
786 	} else {
787 		struct sockaddr_in6 Nxt;
788 		int dummy;
789 		socklen_t len;
790 
791 		Nxt = Dst;
792 		Nxt.sin6_port = htons(DUMMY_PORT);
793 		if (cmsg != NULL)
794 			bcopy(inet6_rthdr_getaddr(cmsg, 1), &Nxt.sin6_addr,
795 			    sizeof(Nxt.sin6_addr));
796 		if ((dummy = socket(AF_INET6, SOCK_DGRAM, 0)) < 0) {
797 			perror("socket");
798 			exit(1);
799 		}
800 		if (connect(dummy, (struct sockaddr *)&Nxt, Nxt.sin6_len) < 0) {
801 			perror("connect");
802 			exit(1);
803 		}
804 		len = sizeof(Src);
805 		if (getsockname(dummy, (struct sockaddr *)&Src, &len) < 0) {
806 			perror("getsockname");
807 			exit(1);
808 		}
809 		if (getnameinfo((struct sockaddr *)&Src, Src.sin6_len,
810 		    src0, sizeof(src0), NULL, 0, NI_NUMERICHOST)) {
811 			fprintf(stderr, "getnameinfo failed for source\n");
812 			exit(1);
813 		}
814 		source = src0;
815 		close(dummy);
816 	}
817 
818 	Src.sin6_port = htons(0);
819 	if (bind(sndsock, (struct sockaddr *)&Src, Src.sin6_len) < 0) {
820 		perror("bind");
821 		exit(1);
822 	}
823 
824 	{
825 		socklen_t len;
826 
827 		len = sizeof(Src);
828 		if (getsockname(sndsock, (struct sockaddr *)&Src, &len) < 0) {
829 			perror("getsockname");
830 			exit(1);
831 		}
832 		srcport = ntohs(Src.sin6_port);
833 	}
834 
835 	/*
836 	 * Message to users
837 	 */
838 	if (getnameinfo((struct sockaddr *)&Dst, Dst.sin6_len, hbuf,
839 	    sizeof(hbuf), NULL, 0, NI_NUMERICHOST))
840 		strlcpy(hbuf, "(invalid)", sizeof(hbuf));
841 	fprintf(stderr, "traceroute6");
842 	fprintf(stderr, " to %s (%s)", hostname, hbuf);
843 	if (source)
844 		fprintf(stderr, " from %s", source);
845 	fprintf(stderr, ", %lu hops max, %lu byte packets\n",
846 	    max_hops, datalen);
847 	(void) fflush(stderr);
848 
849 	if (first_hop > 1)
850 		printf("Skipping %lu intermediate hops\n", first_hop - 1);
851 
852 	/*
853 	 * Main loop
854 	 */
855 	for (hops = first_hop; hops <= max_hops; ++hops) {
856 		struct in6_addr lastaddr;
857 		int got_there = 0;
858 		int unreachable = 0;
859 
860 		printf("%2lu ", hops);
861 		bzero(&lastaddr, sizeof(lastaddr));
862 		for (probe = 0; probe < nprobes; ++probe) {
863 			int cc;
864 			struct timeval t1, t2;
865 
866 			(void) gettimeofday(&t1, NULL);
867 			if (!useicmp && htons((in_port_t)(port + seq + 1)) == 0)
868 				seq++;
869 			send_probe(++seq, hops);
870 			while ((cc = wait_for_reply(rcvsock, &rcvmhdr))) {
871 				(void) gettimeofday(&t2, NULL);
872 				if ((i = packet_ok(&rcvmhdr, cc, seq))) {
873 					if (!IN6_ARE_ADDR_EQUAL(&Rcv.sin6_addr,
874 					    &lastaddr)) {
875 						print(&rcvmhdr, cc);
876 						lastaddr = Rcv.sin6_addr;
877 					}
878 					printf("  %g ms", deltaT(&t1, &t2));
879 					switch (i - 1) {
880 					case ICMP6_DST_UNREACH_NOROUTE:
881 						++unreachable;
882 						printf(" !N");
883 						break;
884 					case ICMP6_DST_UNREACH_ADMIN:
885 						++unreachable;
886 						printf(" !X");
887 						break;
888 					case ICMP6_DST_UNREACH_NOTNEIGHBOR:
889 						++unreachable;
890 						printf(" !S");
891 						break;
892 					case ICMP6_DST_UNREACH_ADDR:
893 						++unreachable;
894 						printf(" !H");
895 						break;
896 					case ICMP6_DST_UNREACH_NOPORT:
897 						if (rcvhlim >= 0 &&
898 						    rcvhlim <= 1)
899 							printf(" !");
900 						++got_there;
901 						break;
902 					}
903 					break;
904 				}
905 			}
906 			if (cc == 0)
907 				printf(" *");
908 			(void) fflush(stdout);
909 		}
910 		putchar('\n');
911 		if (got_there ||
912 		    (unreachable > 0 && unreachable >= ((nprobes + 1) / 2))) {
913 			exit(0);
914 		}
915 	}
916 
917 	exit(0);
918 }
919 
920 int
921 wait_for_reply(sock, mhdr)
922 	int sock;
923 	struct msghdr *mhdr;
924 {
925 #ifdef HAVE_POLL
926 	struct pollfd pfd[1];
927 	int cc = 0;
928 
929 	pfd[0].fd = sock;
930 	pfd[0].events = POLLIN;
931 	pfd[0].revents = 0;
932 
933 	if (poll(pfd, 1, waittime * 1000) > 0)
934 		cc = recvmsg(rcvsock, mhdr, 0);
935 
936 	return(cc);
937 #else
938 	fd_set *fdsp;
939 	struct timeval wait;
940 	int cc = 0, fdsn;
941 
942 	fdsn = howmany(sock + 1, NFDBITS) * sizeof(fd_mask);
943 	if ((fdsp = (fd_set *)malloc(fdsn)) == NULL)
944 		err(1, "malloc");
945 	memset(fdsp, 0, fdsn);
946 	FD_SET(sock, fdsp);
947 	wait.tv_sec = waittime; wait.tv_usec = 0;
948 
949 	if (select(sock+1, fdsp, (fd_set *)0, (fd_set *)0, &wait) > 0)
950 		cc = recvmsg(rcvsock, mhdr, 0);
951 
952 	free(fdsp);
953 	return(cc);
954 #endif
955 }
956 
957 #ifdef IPSEC
958 #ifdef IPSEC_POLICY_IPSEC
959 int
960 setpolicy(so, policy)
961 	int so;
962 	char *policy;
963 {
964 	char *buf;
965 
966 	buf = ipsec_set_policy(policy, strlen(policy));
967 	if (buf == NULL) {
968 		warnx("%s", ipsec_strerror());
969 		return -1;
970 	}
971 	(void)setsockopt(so, IPPROTO_IPV6, IPV6_IPSEC_POLICY,
972 	    buf, ipsec_get_policylen(buf));
973 
974 	free(buf);
975 
976 	return 0;
977 }
978 #endif
979 #endif
980 
981 void
982 send_probe(seq, hops)
983 	int seq;
984 	u_long hops;
985 {
986 	struct timeval tv;
987 	struct tv32 tv32;
988 	int i;
989 
990 	i = hops;
991 	if (setsockopt(sndsock, IPPROTO_IPV6, IPV6_UNICAST_HOPS,
992 	    (char *)&i, sizeof(i)) < 0) {
993 		perror("setsockopt IPV6_UNICAST_HOPS");
994 	}
995 
996 	Dst.sin6_port = htons(port + seq);
997 	(void) gettimeofday(&tv, NULL);
998 	tv32.tv32_sec = htonl(tv.tv_sec);
999 	tv32.tv32_usec = htonl(tv.tv_usec);
1000 
1001 	if (useicmp) {
1002 		struct icmp6_hdr *icp = (struct icmp6_hdr *)outpacket;
1003 
1004 		icp->icmp6_type = ICMP6_ECHO_REQUEST;
1005 		icp->icmp6_code = 0;
1006 		icp->icmp6_cksum = 0;
1007 		icp->icmp6_id = ident;
1008 		icp->icmp6_seq = htons(seq);
1009 		bcopy(&tv32, ((u_int8_t *)outpacket + ICMP6ECHOLEN),
1010 		    sizeof(tv32));
1011 	} else {
1012 		struct opacket *op = outpacket;
1013 
1014 		op->seq = seq;
1015 		op->hops = hops;
1016 		bcopy(&tv32, &op->tv, sizeof tv32);
1017 	}
1018 
1019 	i = sendto(sndsock, (char *)outpacket, datalen , 0,
1020 	    (struct sockaddr *)&Dst, Dst.sin6_len);
1021 	if (i < 0 || i != datalen)  {
1022 		if (i < 0)
1023 			perror("sendto");
1024 		printf("traceroute6: wrote %s %lu chars, ret=%d\n",
1025 		    hostname, datalen, i);
1026 		(void) fflush(stdout);
1027 	}
1028 }
1029 
1030 int
1031 get_hoplim(mhdr)
1032 	struct msghdr *mhdr;
1033 {
1034 	struct cmsghdr *cm;
1035 
1036 	for (cm = (struct cmsghdr *)CMSG_FIRSTHDR(mhdr); cm;
1037 	    cm = (struct cmsghdr *)CMSG_NXTHDR(mhdr, cm)) {
1038 		if (cm->cmsg_level == IPPROTO_IPV6 &&
1039 		    cm->cmsg_type == IPV6_HOPLIMIT &&
1040 		    cm->cmsg_len == CMSG_LEN(sizeof(int)))
1041 			return(*(int *)CMSG_DATA(cm));
1042 	}
1043 
1044 	return(-1);
1045 }
1046 
1047 double
1048 deltaT(t1p, t2p)
1049 	struct timeval *t1p, *t2p;
1050 {
1051 	double dt;
1052 
1053 	dt = (double)(t2p->tv_sec - t1p->tv_sec) * 1000.0 +
1054 	    (double)(t2p->tv_usec - t1p->tv_usec) / 1000.0;
1055 	return (dt);
1056 }
1057 
1058 /*
1059  * Convert an ICMP "type" field to a printable string.
1060  */
1061 char *
1062 pr_type(t0)
1063 	int t0;
1064 {
1065 	u_char t = t0 & 0xff;
1066 	char *cp;
1067 
1068 	switch (t) {
1069 	case ICMP6_DST_UNREACH:
1070 		cp = "Destination Unreachable";
1071 		break;
1072 	case ICMP6_PACKET_TOO_BIG:
1073 		cp = "Packet Too Big";
1074 		break;
1075 	case ICMP6_TIME_EXCEEDED:
1076 		cp = "Time Exceeded";
1077 		break;
1078 	case ICMP6_PARAM_PROB:
1079 		cp = "Parameter Problem";
1080 		break;
1081 	case ICMP6_ECHO_REQUEST:
1082 		cp = "Echo Request";
1083 		break;
1084 	case ICMP6_ECHO_REPLY:
1085 		cp = "Echo Reply";
1086 		break;
1087 	case ICMP6_MEMBERSHIP_QUERY:
1088 		cp = "Group Membership Query";
1089 		break;
1090 	case ICMP6_MEMBERSHIP_REPORT:
1091 		cp = "Group Membership Report";
1092 		break;
1093 	case ICMP6_MEMBERSHIP_REDUCTION:
1094 		cp = "Group Membership Reduction";
1095 		break;
1096 	case ND_ROUTER_SOLICIT:
1097 		cp = "Router Solicitation";
1098 		break;
1099 	case ND_ROUTER_ADVERT:
1100 		cp = "Router Advertisement";
1101 		break;
1102 	case ND_NEIGHBOR_SOLICIT:
1103 		cp = "Neighbor Solicitation";
1104 		break;
1105 	case ND_NEIGHBOR_ADVERT:
1106 		cp = "Neighbor Advertisement";
1107 		break;
1108 	case ND_REDIRECT:
1109 		cp = "Redirect";
1110 		break;
1111 	default:
1112 		cp = "Unknown";
1113 		break;
1114 	}
1115 	return cp;
1116 }
1117 
1118 int
1119 packet_ok(mhdr, cc, seq)
1120 	struct msghdr *mhdr;
1121 	int cc;
1122 	int seq;
1123 {
1124 	struct icmp6_hdr *icp;
1125 	struct sockaddr_in6 *from = (struct sockaddr_in6 *)mhdr->msg_name;
1126 	u_char type, code;
1127 	char *buf = (char *)mhdr->msg_iov[0].iov_base;
1128 	struct cmsghdr *cm;
1129 	int *hlimp;
1130 	char hbuf[NI_MAXHOST];
1131 
1132 #ifdef OLDRAWSOCKET
1133 	int hlen;
1134 	struct ip6_hdr *ip;
1135 #endif
1136 
1137 #ifdef OLDRAWSOCKET
1138 	ip = (struct ip6_hdr *) buf;
1139 	hlen = sizeof(struct ip6_hdr);
1140 	if (cc < hlen + sizeof(struct icmp6_hdr)) {
1141 		if (verbose) {
1142 			if (getnameinfo((struct sockaddr *)from, from->sin6_len,
1143 			    hbuf, sizeof(hbuf), NULL, 0, NI_NUMERICHOST) != 0)
1144 				strlcpy(hbuf, "invalid", sizeof(hbuf));
1145 			printf("packet too short (%d bytes) from %s\n", cc,
1146 			    hbuf);
1147 		}
1148 		return (0);
1149 	}
1150 	cc -= hlen;
1151 	icp = (struct icmp6_hdr *)(buf + hlen);
1152 #else
1153 	if (cc < sizeof(struct icmp6_hdr)) {
1154 		if (verbose) {
1155 			if (getnameinfo((struct sockaddr *)from, from->sin6_len,
1156 			    hbuf, sizeof(hbuf), NULL, 0, NI_NUMERICHOST) != 0)
1157 				strlcpy(hbuf, "invalid", sizeof(hbuf));
1158 			printf("data too short (%d bytes) from %s\n", cc, hbuf);
1159 		}
1160 		return(0);
1161 	}
1162 	icp = (struct icmp6_hdr *)buf;
1163 #endif
1164 	/* get optional information via advanced API */
1165 	rcvpktinfo = NULL;
1166 	hlimp = NULL;
1167 	for (cm = (struct cmsghdr *)CMSG_FIRSTHDR(mhdr); cm;
1168 	    cm = (struct cmsghdr *)CMSG_NXTHDR(mhdr, cm)) {
1169 		if (cm->cmsg_level == IPPROTO_IPV6 &&
1170 		    cm->cmsg_type == IPV6_PKTINFO &&
1171 		    cm->cmsg_len ==
1172 		    CMSG_LEN(sizeof(struct in6_pktinfo)))
1173 			rcvpktinfo = (struct in6_pktinfo *)(CMSG_DATA(cm));
1174 
1175 		if (cm->cmsg_level == IPPROTO_IPV6 &&
1176 		    cm->cmsg_type == IPV6_HOPLIMIT &&
1177 		    cm->cmsg_len == CMSG_LEN(sizeof(int)))
1178 			hlimp = (int *)CMSG_DATA(cm);
1179 	}
1180 	if (rcvpktinfo == NULL || hlimp == NULL) {
1181 		warnx("failed to get received hop limit or packet info");
1182 #if 0
1183 		return(0);
1184 #else
1185 		rcvhlim = 0;	/*XXX*/
1186 #endif
1187 	}
1188 	else
1189 		rcvhlim = *hlimp;
1190 
1191 	type = icp->icmp6_type;
1192 	code = icp->icmp6_code;
1193 	if ((type == ICMP6_TIME_EXCEEDED && code == ICMP6_TIME_EXCEED_TRANSIT)
1194 	    || type == ICMP6_DST_UNREACH) {
1195 		struct ip6_hdr *hip;
1196 		struct udphdr *up;
1197 
1198 		hip = (struct ip6_hdr *)(icp + 1);
1199 		if ((up = get_udphdr(hip, (u_char *)(buf + cc))) == NULL) {
1200 			if (verbose)
1201 				warnx("failed to get upper layer header");
1202 			return(0);
1203 		}
1204 		if (useicmp &&
1205 		    ((struct icmp6_hdr *)up)->icmp6_id == ident &&
1206 		    ((struct icmp6_hdr *)up)->icmp6_seq == htons(seq))
1207 			return (type == ICMP6_TIME_EXCEEDED ? -1 : code + 1);
1208 		else if (!useicmp &&
1209 		    up->uh_sport == htons(srcport) &&
1210 		    up->uh_dport == htons(port + seq))
1211 			return (type == ICMP6_TIME_EXCEEDED ? -1 : code + 1);
1212 	} else if (useicmp && type == ICMP6_ECHO_REPLY) {
1213 		if (icp->icmp6_id == ident &&
1214 		    icp->icmp6_seq == htons(seq))
1215 			return (ICMP6_DST_UNREACH_NOPORT + 1);
1216 	}
1217 	if (verbose) {
1218 		char sbuf[NI_MAXHOST+1], dbuf[INET6_ADDRSTRLEN];
1219 		u_int8_t *p;
1220 		int i;
1221 
1222 		if (getnameinfo((struct sockaddr *)from, from->sin6_len,
1223 		    sbuf, sizeof(sbuf), NULL, 0, NI_NUMERICHOST) != 0)
1224 			strlcpy(sbuf, "invalid", sizeof(sbuf));
1225 		printf("\n%d bytes from %s to %s", cc, sbuf,
1226 		    rcvpktinfo ? inet_ntop(AF_INET6, &rcvpktinfo->ipi6_addr,
1227 		    dbuf, sizeof(dbuf)) : "?");
1228 		printf(": icmp type %d (%s) code %d\n", type, pr_type(type),
1229 		    icp->icmp6_code);
1230 		p = (u_int8_t *)(icp + 1);
1231 #define WIDTH	16
1232 		for (i = 0; i < cc; i++) {
1233 			if (i % WIDTH == 0)
1234 				printf("%04x:", i);
1235 			if (i % 4 == 0)
1236 				printf(" ");
1237 			printf("%02x", p[i]);
1238 			if (i % WIDTH == WIDTH - 1)
1239 				printf("\n");
1240 		}
1241 		if (cc % WIDTH != 0)
1242 			printf("\n");
1243 	}
1244 	return(0);
1245 }
1246 
1247 /*
1248  * Increment pointer until find the UDP or ICMP header.
1249  */
1250 struct udphdr *
1251 get_udphdr(ip6, lim)
1252 	struct ip6_hdr *ip6;
1253 	u_char *lim;
1254 {
1255 	u_char *cp = (u_char *)ip6, nh;
1256 	int hlen;
1257 
1258 	if (cp + sizeof(*ip6) >= lim)
1259 		return(NULL);
1260 
1261 	nh = ip6->ip6_nxt;
1262 	cp += sizeof(struct ip6_hdr);
1263 
1264 	while (lim - cp >= 8) {
1265 		switch (nh) {
1266 		case IPPROTO_ESP:
1267 		case IPPROTO_TCP:
1268 			return(NULL);
1269 		case IPPROTO_ICMPV6:
1270 			return(useicmp ? (struct udphdr *)cp : NULL);
1271 		case IPPROTO_UDP:
1272 			return(useicmp ? NULL : (struct udphdr *)cp);
1273 		case IPPROTO_FRAGMENT:
1274 			hlen = sizeof(struct ip6_frag);
1275 			nh = ((struct ip6_frag *)cp)->ip6f_nxt;
1276 			break;
1277 		case IPPROTO_AH:
1278 			hlen = (((struct ip6_ext *)cp)->ip6e_len + 2) << 2;
1279 			nh = ((struct ip6_ext *)cp)->ip6e_nxt;
1280 			break;
1281 		default:
1282 			hlen = (((struct ip6_ext *)cp)->ip6e_len + 1) << 3;
1283 			nh = ((struct ip6_ext *)cp)->ip6e_nxt;
1284 			break;
1285 		}
1286 
1287 		cp += hlen;
1288 	}
1289 
1290 	return(NULL);
1291 }
1292 
1293 void
1294 print(mhdr, cc)
1295 	struct msghdr *mhdr;
1296 	int cc;
1297 {
1298 	struct sockaddr_in6 *from = (struct sockaddr_in6 *)mhdr->msg_name;
1299 	char hbuf[NI_MAXHOST];
1300 
1301 	if (getnameinfo((struct sockaddr *)from, from->sin6_len,
1302 	    hbuf, sizeof(hbuf), NULL, 0, NI_NUMERICHOST) != 0)
1303 		strlcpy(hbuf, "invalid", sizeof(hbuf));
1304 	if (nflag)
1305 		printf(" %s", hbuf);
1306 	else if (lflag)
1307 		printf(" %s (%s)", inetname((struct sockaddr *)from), hbuf);
1308 	else
1309 		printf(" %s", inetname((struct sockaddr *)from));
1310 
1311 	if (verbose) {
1312 #ifdef OLDRAWSOCKET
1313 		printf(" %d bytes to %s", cc,
1314 		    rcvpktinfo ? inet_ntop(AF_INET6, &rcvpktinfo->ipi6_addr,
1315 		    hbuf, sizeof(hbuf)) : "?");
1316 #else
1317 		printf(" %d bytes of data to %s", cc,
1318 		    rcvpktinfo ?  inet_ntop(AF_INET6, &rcvpktinfo->ipi6_addr,
1319 		    hbuf, sizeof(hbuf)) : "?");
1320 #endif
1321 	}
1322 }
1323 
1324 /*
1325  * Construct an Internet address representation.
1326  * If the nflag has been supplied, give
1327  * numeric value, otherwise try for symbolic name.
1328  */
1329 const char *
1330 inetname(sa)
1331 	struct sockaddr *sa;
1332 {
1333 	static char line[NI_MAXHOST], domain[MAXHOSTNAMELEN + 1];
1334 	static int first = 1;
1335 	char *cp;
1336 
1337 	if (first && !nflag) {
1338 		first = 0;
1339 		if (gethostname(domain, sizeof(domain)) == 0 &&
1340 		    (cp = strchr(domain, '.')))
1341 			(void) strlcpy(domain, cp + 1, sizeof(domain));
1342 		else
1343 			domain[0] = 0;
1344 	}
1345 	cp = NULL;
1346 	if (!nflag) {
1347 		if (getnameinfo(sa, sa->sa_len, line, sizeof(line), NULL, 0,
1348 		    NI_NAMEREQD) == 0) {
1349 			if ((cp = strchr(line, '.')) &&
1350 			    !strcmp(cp + 1, domain))
1351 				*cp = 0;
1352 			cp = line;
1353 		}
1354 	}
1355 	if (cp)
1356 		return cp;
1357 
1358 	if (getnameinfo(sa, sa->sa_len, line, sizeof(line), NULL, 0,
1359 	    NI_NUMERICHOST) != 0)
1360 		strlcpy(line, "invalid", sizeof(line));
1361 	return line;
1362 }
1363 
1364 void
1365 usage()
1366 {
1367 
1368 	fprintf(stderr,
1369 "usage: traceroute6 [-dIlnrv] [-f firsthop] [-g gateway] [-m hoplimit]\n"
1370 "       [-p port] [-q probes] [-s src] [-w waittime] target [datalen]\n");
1371 	exit(1);
1372 }
1373