1 /*
2 * Modified for NRL 4.4BSD IPv6 release.
3 * 07/31/96 bgp
4 *
5 * Search for "#ifdef NRL" to find the changes.
6 */
7
8 /*
9 * Modified for Linux IPv6 by Pedro Roque <roque@di.fc.ul.pt>
10 * 31/07/1996
11 *
12 * As ICMP error messages for IPv6 now include more than 8 bytes
13 * UDP datagrams are now sent via an UDP socket instead of magic
14 * RAW socket tricks.
15 *
16 * Original copyright and comments left intact. They might not
17 * match the code anymore.
18 */
19
20 /*-
21 * Copyright (c) 1990, 1993
22 * The Regents of the University of California. All rights reserved.
23 *
24 * This code is derived from software contributed to Berkeley by
25 * Van Jacobson.
26 *
27 * Redistribution and use in source and binary forms, with or without
28 * modification, are permitted provided that the following conditions
29 * are met:
30 * 1. Redistributions of source code must retain the above copyright
31 * notice, this list of conditions and the following disclaimer.
32 * 2. Redistributions in binary form must reproduce the above copyright
33 * notice, this list of conditions and the following disclaimer in the
34 * documentation and/or other materials provided with the distribution.
35 * 3. All advertising materials mentioning features or use of this software
36 * must display the following acknowledgement:
37 * This product includes software developed by the University of
38 * California, Berkeley and its contributors.
39 * 4. Neither the name of the University nor the names of its contributors
40 * may be used to endorse or promote products derived from this software
41 * without specific prior written permission.
42 *
43 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
44 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
45 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
46 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
47 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
48 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
49 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
50 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
51 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
52 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
53 * SUCH DAMAGE.
54 */
55
56 #ifndef lint
57 char copyright[] =
58 "@(#) Copyright (c) 1990, 1993\n\
59 The Regents of the University of California. All rights reserved.\n";
60 #endif /* not lint */
61
62 /*
63 * traceroute host - trace the route ip packets follow going to "host".
64 *
65 * Attempt to trace the route an ip packet would follow to some
66 * internet host. We find out intermediate hops by launching probe
67 * packets with a small ttl (time to live) then listening for an
68 * icmp "time exceeded" reply from a gateway. We start our probes
69 * with a ttl of one and increase by one until we get an icmp "port
70 * unreachable" (which means we got to "host") or hit a max (which
71 * defaults to 30 hops & can be changed with the -m flag). Three
72 * probes (change with -q flag) are sent at each ttl setting and a
73 * line is printed showing the ttl, address of the gateway and
74 * round trip time of each probe. If the probe answers come from
75 * different gateways, the address of each responding system will
76 * be printed. If there is no response within a 5 sec. timeout
77 * interval (changed with the -w flag), a "*" is printed for that
78 * probe.
79 *
80 * Probe packets are UDP format. We don't want the destination
81 * host to process them so the destination port is set to an
82 * unlikely value (if some clod on the destination is using that
83 * value, it can be changed with the -p flag).
84 *
85 * A sample use might be:
86 *
87 * [yak 71]% traceroute nis.nsf.net.
88 * traceroute to nis.nsf.net (35.1.1.48), 30 hops max, 56 byte packet
89 * 1 helios.ee.lbl.gov (128.3.112.1) 19 ms 19 ms 0 ms
90 * 2 lilac-dmc.Berkeley.EDU (128.32.216.1) 39 ms 39 ms 19 ms
91 * 3 lilac-dmc.Berkeley.EDU (128.32.216.1) 39 ms 39 ms 19 ms
92 * 4 ccngw-ner-cc.Berkeley.EDU (128.32.136.23) 39 ms 40 ms 39 ms
93 * 5 ccn-nerif22.Berkeley.EDU (128.32.168.22) 39 ms 39 ms 39 ms
94 * 6 128.32.197.4 (128.32.197.4) 40 ms 59 ms 59 ms
95 * 7 131.119.2.5 (131.119.2.5) 59 ms 59 ms 59 ms
96 * 8 129.140.70.13 (129.140.70.13) 99 ms 99 ms 80 ms
97 * 9 129.140.71.6 (129.140.71.6) 139 ms 239 ms 319 ms
98 * 10 129.140.81.7 (129.140.81.7) 220 ms 199 ms 199 ms
99 * 11 nic.merit.edu (35.1.1.48) 239 ms 239 ms 239 ms
100 *
101 * Note that lines 2 & 3 are the same. This is due to a buggy
102 * kernel on the 2nd hop system -- lbl-csam.arpa -- that forwards
103 * packets with a zero ttl.
104 *
105 * A more interesting example is:
106 *
107 * [yak 72]% traceroute allspice.lcs.mit.edu.
108 * traceroute to allspice.lcs.mit.edu (18.26.0.115), 30 hops max
109 * 1 helios.ee.lbl.gov (128.3.112.1) 0 ms 0 ms 0 ms
110 * 2 lilac-dmc.Berkeley.EDU (128.32.216.1) 19 ms 19 ms 19 ms
111 * 3 lilac-dmc.Berkeley.EDU (128.32.216.1) 39 ms 19 ms 19 ms
112 * 4 ccngw-ner-cc.Berkeley.EDU (128.32.136.23) 19 ms 39 ms 39 ms
113 * 5 ccn-nerif22.Berkeley.EDU (128.32.168.22) 20 ms 39 ms 39 ms
114 * 6 128.32.197.4 (128.32.197.4) 59 ms 119 ms 39 ms
115 * 7 131.119.2.5 (131.119.2.5) 59 ms 59 ms 39 ms
116 * 8 129.140.70.13 (129.140.70.13) 80 ms 79 ms 99 ms
117 * 9 129.140.71.6 (129.140.71.6) 139 ms 139 ms 159 ms
118 * 10 129.140.81.7 (129.140.81.7) 199 ms 180 ms 300 ms
119 * 11 129.140.72.17 (129.140.72.17) 300 ms 239 ms 239 ms
120 * 12 * * *
121 * 13 128.121.54.72 (128.121.54.72) 259 ms 499 ms 279 ms
122 * 14 * * *
123 * 15 * * *
124 * 16 * * *
125 * 17 * * *
126 * 18 ALLSPICE.LCS.MIT.EDU (18.26.0.115) 339 ms 279 ms 279 ms
127 *
128 * (I start to see why I'm having so much trouble with mail to
129 * MIT.) Note that the gateways 12, 14, 15, 16 & 17 hops away
130 * either don't send ICMP "time exceeded" messages or send them
131 * with a ttl too small to reach us. 14 - 17 are running the
132 * MIT C Gateway code that doesn't send "time exceeded"s. God
133 * only knows what's going on with 12.
134 *
135 * The silent gateway 12 in the above may be the result of a bug in
136 * the 4.[23]BSD network code (and its derivatives): 4.x (x <= 3)
137 * sends an unreachable message using whatever ttl remains in the
138 * original datagram. Since, for gateways, the remaining ttl is
139 * zero, the icmp "time exceeded" is guaranteed to not make it back
140 * to us. The behavior of this bug is slightly more interesting
141 * when it appears on the destination system:
142 *
143 * 1 helios.ee.lbl.gov (128.3.112.1) 0 ms 0 ms 0 ms
144 * 2 lilac-dmc.Berkeley.EDU (128.32.216.1) 39 ms 19 ms 39 ms
145 * 3 lilac-dmc.Berkeley.EDU (128.32.216.1) 19 ms 39 ms 19 ms
146 * 4 ccngw-ner-cc.Berkeley.EDU (128.32.136.23) 39 ms 40 ms 19 ms
147 * 5 ccn-nerif35.Berkeley.EDU (128.32.168.35) 39 ms 39 ms 39 ms
148 * 6 csgw.Berkeley.EDU (128.32.133.254) 39 ms 59 ms 39 ms
149 * 7 * * *
150 * 8 * * *
151 * 9 * * *
152 * 10 * * *
153 * 11 * * *
154 * 12 * * *
155 * 13 rip.Berkeley.EDU (128.32.131.22) 59 ms ! 39 ms ! 39 ms !
156 *
157 * Notice that there are 12 "gateways" (13 is the final
158 * destination) and exactly the last half of them are "missing".
159 * What's really happening is that rip (a Sun-3 running Sun OS3.5)
160 * is using the ttl from our arriving datagram as the ttl in its
161 * icmp reply. So, the reply will time out on the return path
162 * (with no notice sent to anyone since icmp's aren't sent for
163 * icmp's) until we probe with a ttl that's at least twice the path
164 * length. I.e., rip is really only 7 hops away. A reply that
165 * returns with a ttl of 1 is a clue this problem exists.
166 * Traceroute prints a "!" after the time if the ttl is <= 1.
167 * Since vendors ship a lot of obsolete (DEC's Ultrix, Sun 3.x) or
168 * non-standard (HPUX) software, expect to see this problem
169 * frequently and/or take care picking the target host of your
170 * probes.
171 *
172 * Other possible annotations after the time are !H, !N, !P (got a host,
173 * network or protocol unreachable, respectively), !S or !F (source
174 * route failed or fragmentation needed -- neither of these should
175 * ever occur and the associated gateway is busted if you see one). If
176 * almost all the probes result in some kind of unreachable, traceroute
177 * will give up and exit.
178 *
179 * Notes
180 * -----
181 * This program must be run by root or be setuid. (I suggest that
182 * you *don't* make it setuid -- casual use could result in a lot
183 * of unnecessary traffic on our poor, congested nets.)
184 *
185 * This program requires a kernel mod that does not appear in any
186 * system available from Berkeley: A raw ip socket using proto
187 * IPPROTO_RAW must interpret the data sent as an ip datagram (as
188 * opposed to data to be wrapped in a ip datagram). See the README
189 * file that came with the source to this program for a description
190 * of the mods I made to /sys/netinet/raw_ip.c. Your mileage may
191 * vary. But, again, ANY 4.x (x < 4) BSD KERNEL WILL HAVE TO BE
192 * MODIFIED TO RUN THIS PROGRAM.
193 *
194 * The udp port usage may appear bizarre (well, ok, it is bizarre).
195 * The problem is that an icmp message only contains 8 bytes of
196 * data from the original datagram. 8 bytes is the size of a udp
197 * header so, if we want to associate replies with the original
198 * datagram, the necessary information must be encoded into the
199 * udp header (the ip id could be used but there's no way to
200 * interlock with the kernel's assignment of ip id's and, anyway,
201 * it would have taken a lot more kernel hacking to allow this
202 * code to set the ip id). So, to allow two or more users to
203 * use traceroute simultaneously, we use this task's pid as the
204 * source port (the high bit is set to move the port number out
205 * of the "likely" range). To keep track of which probe is being
206 * replied to (so times and/or hop counts don't get confused by a
207 * reply that was delayed in transit), we increment the destination
208 * port number before each probe.
209 *
210 * Don't use this as a coding example. I was trying to find a
211 * routing problem and this code sort-of popped out after 48 hours
212 * without sleep. I was amazed it ever compiled, much less ran.
213 *
214 * I stole the idea for this program from Steve Deering. Since
215 * the first release, I've learned that had I attended the right
216 * IETF working group meetings, I also could have stolen it from Guy
217 * Almes or Matt Mathis. I don't know (or care) who came up with
218 * the idea first. I envy the originators' perspicacity and I'm
219 * glad they didn't keep the idea a secret.
220 *
221 * Tim Seaver, Ken Adelman and C. Philip Wood provided bug fixes and/or
222 * enhancements to the original distribution.
223 *
224 * I've hacked up a round-trip-route version of this that works by
225 * sending a loose-source-routed udp datagram through the destination
226 * back to yourself. Unfortunately, SO many gateways botch source
227 * routing, the thing is almost worthless. Maybe one day...
228 *
229 * -- Van Jacobson (van@helios.ee.lbl.gov)
230 * Tue Dec 20 03:50:13 PST 1988
231 */
232
233 #include <sys/param.h>
234 #include <sys/time.h>
235 #include <sys/socket.h>
236 #include <sys/file.h>
237 #include <sys/ioctl.h>
238 #include <net/if.h>
239
240 #if __linux__
241 #include <endian.h>
242 #endif
243 #include <netinet/in_systm.h>
244 #include <netinet/in.h>
245 #include <netinet/ip.h>
246 #include <netinet/ip_icmp.h>
247 #include <netinet/udp.h>
248
249 #include <netinet/ip6.h>
250 #include <netinet/icmp6.h>
251 #include <linux/types.h>
252 #ifdef CAPABILITIES
253 #include <sys/capability.h>
254 #endif
255
256 #ifdef USE_IDN
257 #include <idna.h>
258 #include <locale.h>
259 #endif
260
261 #include <arpa/inet.h>
262
263 #include <netdb.h>
264 #include <stdio.h>
265 #include <errno.h>
266 #include <stdlib.h>
267 #include <string.h>
268 #include <unistd.h>
269
270 #include "SNAPSHOT.h"
271
272 #ifndef SOL_IPV6
273 #define SOL_IPV6 IPPROTO_IPV6
274 #endif
275
276 #define MAXPACKET 65535
277 #define MAX_HOSTNAMELEN NI_MAXHOST
278
279 #ifndef FD_SET
280 #define NFDBITS (8*sizeof(fd_set))
281 #define FD_SETSIZE NFDBITS
282 #define FD_SET(n, p) ((p)->fds_bits[(n)/NFDBITS] |= (1 << ((n) % NFDBITS)))
283 #define FD_CLR(n, p) ((p)->fds_bits[(n)/NFDBITS] &= ~(1 << ((n) % NFDBITS)))
284 #define FD_ISSET(n, p) ((p)->fds_bits[(n)/NFDBITS] & (1 << ((n) % NFDBITS)))
285 #define FD_ZERO(p) memset((char *)(p), 0, sizeof(*(p)))
286 #endif
287
288 #define Fprintf (void)fprintf
289 #define Printf (void)printf
290
291 u_char packet[512]; /* last inbound (icmp) packet */
292
293 int wait_for_reply(int, struct sockaddr_in6 *, struct in6_addr *, int);
294 int packet_ok(u_char *buf, int cc, struct sockaddr_in6 *from,
295 struct in6_addr *to, int seq, struct timeval *);
296 void send_probe(int seq, int ttl);
297 double deltaT (struct timeval *, struct timeval *);
298 void print(unsigned char *buf, int cc, struct sockaddr_in6 *from);
299 void tvsub (struct timeval *, struct timeval *);
300 void usage(void);
301
302 int icmp_sock; /* receive (icmp) socket file descriptor */
303 int sndsock; /* send (udp) socket file descriptor */
304 struct timezone tz; /* leftover */
305
306 struct sockaddr_in6 whereto; /* Who to try to reach */
307
308 struct sockaddr_in6 saddr;
309 struct sockaddr_in6 firsthop;
310 char *source = NULL;
311 char *device = NULL;
312 char *hostname;
313
314 int nprobes = 3;
315 int max_ttl = 30;
316 pid_t ident;
317 u_short port = 32768+666; /* start udp dest port # for probe packets */
318 int options; /* socket options */
319 int verbose;
320 int waittime = 5; /* time to wait for response (in seconds) */
321 int nflag; /* print addresses numerically */
322
323
324 struct pkt_format
325 {
326 __u32 ident;
327 __u32 seq;
328 struct timeval tv;
329 };
330
331 char *sendbuff;
332 int datalen = sizeof(struct pkt_format);
333
334
335
main(int argc,char * argv[])336 int main(int argc, char *argv[])
337 {
338 char pa[MAX_HOSTNAMELEN];
339 extern char *optarg;
340 extern int optind;
341 struct hostent *hp;
342 struct sockaddr_in6 from, *to;
343 int ch, i, on, probe, seq, tos, ttl;
344 int socket_errno;
345
346 icmp_sock = socket(AF_INET6, SOCK_RAW, IPPROTO_ICMPV6);
347 socket_errno = errno;
348
349 if (setuid(getuid())) {
350 perror("traceroute6: setuid");
351 exit(-1);
352 }
353 #ifdef CAPABILITIES
354 {
355 cap_t caps = cap_init();
356 if (cap_set_proc(caps)) {
357 perror("traceroute6: cap_set_proc");
358 exit(-1);
359 }
360 cap_free(caps);
361 }
362 #endif
363
364 #ifdef USE_IDN
365 setlocale(LC_ALL, "");
366 #endif
367
368 on = 1;
369 seq = tos = 0;
370 to = (struct sockaddr_in6 *)&whereto;
371 while ((ch = getopt(argc, argv, "dm:np:q:rs:t:w:vi:g:V")) != EOF) {
372 switch(ch) {
373 case 'd':
374 options |= SO_DEBUG;
375 break;
376 case 'm':
377 max_ttl = atoi(optarg);
378 if (max_ttl <= 1) {
379 Fprintf(stderr,
380 "traceroute: max ttl must be >1.\n");
381 exit(1);
382 }
383 break;
384 case 'n':
385 nflag++;
386 break;
387 case 'p':
388 port = atoi(optarg);
389 if (port < 1) {
390 Fprintf(stderr,
391 "traceroute: port must be >0.\n");
392 exit(1);
393 }
394 break;
395 case 'q':
396 nprobes = atoi(optarg);
397 if (nprobes < 1) {
398 Fprintf(stderr,
399 "traceroute: nprobes must be >0.\n");
400 exit(1);
401 }
402 break;
403 case 'r':
404 options |= SO_DONTROUTE;
405 break;
406 case 's':
407 /*
408 * set the ip source address of the outbound
409 * probe (e.g., on a multi-homed host).
410 */
411 source = optarg;
412 break;
413 case 'i':
414 device = optarg;
415 break;
416 case 'g':
417 Fprintf(stderr, "Sorry, rthdr is not yet supported\n");
418 break;
419 case 'v':
420 verbose++;
421 break;
422 case 'w':
423 waittime = atoi(optarg);
424 if (waittime <= 1) {
425 Fprintf(stderr,
426 "traceroute: wait must be >1 sec.\n");
427 exit(1);
428 }
429 break;
430 case 'V':
431 printf("traceroute6 utility, iputils-%s\n", SNAPSHOT);
432 exit(0);
433 default:
434 usage();
435 }
436 }
437 argc -= optind;
438 argv += optind;
439
440 if (argc < 1)
441 usage();
442
443 setlinebuf (stdout);
444
445 (void) memset((char *)&whereto, 0, sizeof(whereto));
446
447 to->sin6_family = AF_INET6;
448 to->sin6_port = htons(port);
449
450 if (inet_pton(AF_INET6, *argv, &to->sin6_addr) > 0) {
451 hostname = *argv;
452 } else {
453 char *idn = NULL;
454 #ifdef USE_IDN
455 if (idna_to_ascii_lz(*argv, &idn, 0) != IDNA_SUCCESS)
456 idn = NULL;
457 #endif
458 hp = gethostbyname2(idn ? idn : *argv, AF_INET6);
459 if (hp) {
460 memmove((caddr_t)&to->sin6_addr, hp->h_addr, sizeof(to->sin6_addr));
461 hostname = (char *)hp->h_name;
462 } else {
463 (void)fprintf(stderr,
464 "traceroute: unknown host %s\n", *argv);
465 exit(1);
466 }
467 }
468 firsthop = *to;
469 if (*++argv) {
470 datalen = atoi(*argv);
471 /* Message for rpm maintainers: have _shame_. If you want
472 * to fix something send the patch to me for sanity checking.
473 * "datalen" patch is a shit. */
474 if (datalen == 0)
475 datalen = sizeof(struct pkt_format);
476 else if (datalen < (int)sizeof(struct pkt_format) ||
477 datalen >= MAXPACKET) {
478 Fprintf(stderr,
479 "traceroute: packet size must be %d <= s < %d.\n",
480 (int)sizeof(struct pkt_format), MAXPACKET);
481 exit(1);
482 }
483 }
484
485 ident = getpid();
486
487 sendbuff = malloc(datalen);
488 if (sendbuff == NULL) {
489 fprintf(stderr, "malloc failed\n");
490 exit(1);
491 }
492
493 if (icmp_sock < 0) {
494 errno = socket_errno;
495 perror("traceroute6: icmp socket");
496 exit(1);
497 }
498
499 #ifdef IPV6_RECVPKTINFO
500 setsockopt(icmp_sock, SOL_IPV6, IPV6_RECVPKTINFO, &on, sizeof(on));
501 setsockopt(icmp_sock, SOL_IPV6, IPV6_2292PKTINFO, &on, sizeof(on));
502 #else
503 setsockopt(icmp_sock, SOL_IPV6, IPV6_PKTINFO, &on, sizeof(on));
504 #endif
505
506 if (options & SO_DEBUG)
507 setsockopt(icmp_sock, SOL_SOCKET, SO_DEBUG,
508 (char *)&on, sizeof(on));
509 if (options & SO_DONTROUTE)
510 setsockopt(icmp_sock, SOL_SOCKET, SO_DONTROUTE,
511 (char *)&on, sizeof(on));
512
513 #ifdef __linux__
514 on = 2;
515 if (setsockopt(icmp_sock, SOL_RAW, IPV6_CHECKSUM, &on, sizeof(on)) < 0) {
516 /* checksum should be enabled by default and setting this
517 * option might fail anyway.
518 */
519 fprintf(stderr, "setsockopt(RAW_CHECKSUM) failed - try to continue.");
520 }
521 #endif
522
523 if ((sndsock = socket(AF_INET6, SOCK_DGRAM, 0)) < 0) {
524 perror("traceroute: UDP socket");
525 exit(5);
526 }
527 #ifdef SO_SNDBUF
528 if (setsockopt(sndsock, SOL_SOCKET, SO_SNDBUF, (char *)&datalen,
529 sizeof(datalen)) < 0) {
530 perror("traceroute: SO_SNDBUF");
531 exit(6);
532 }
533 #endif /* SO_SNDBUF */
534
535 if (options & SO_DEBUG)
536 (void) setsockopt(sndsock, SOL_SOCKET, SO_DEBUG,
537 (char *)&on, sizeof(on));
538 if (options & SO_DONTROUTE)
539 (void) setsockopt(sndsock, SOL_SOCKET, SO_DONTROUTE,
540 (char *)&on, sizeof(on));
541
542 if (source == NULL) {
543 socklen_t alen;
544 int probe_fd = socket(AF_INET6, SOCK_DGRAM, 0);
545
546 if (probe_fd < 0) {
547 perror("socket");
548 exit(1);
549 }
550 if (device) {
551 if (setsockopt(probe_fd, SOL_SOCKET, SO_BINDTODEVICE, device, strlen(device)+1) == -1)
552 perror("WARNING: interface is ignored");
553 }
554 firsthop.sin6_port = htons(1025);
555 if (connect(probe_fd, (struct sockaddr*)&firsthop, sizeof(firsthop)) == -1) {
556 perror("connect");
557 exit(1);
558 }
559 alen = sizeof(saddr);
560 if (getsockname(probe_fd, (struct sockaddr*)&saddr, &alen) == -1) {
561 perror("getsockname");
562 exit(1);
563 }
564 saddr.sin6_port = 0;
565 close(probe_fd);
566 } else {
567 (void) memset((char *)&saddr, 0, sizeof(saddr));
568 saddr.sin6_family = AF_INET6;
569 if (inet_pton(AF_INET6, source, &saddr.sin6_addr) <= 0)
570 {
571 Printf("traceroute: unknown addr %s\n", source);
572 exit(1);
573 }
574 }
575
576 if (bind(sndsock, (struct sockaddr *)&saddr, sizeof(saddr)) < 0) {
577 perror ("traceroute: bind sending socket");
578 exit (1);
579 }
580 if (bind(icmp_sock, (struct sockaddr *)&saddr, sizeof(saddr)) < 0) {
581 perror ("traceroute: bind icmp6 socket");
582 exit (1);
583 }
584
585 Fprintf(stderr, "traceroute to %s (%s)", hostname,
586 inet_ntop(AF_INET6, &to->sin6_addr, pa, sizeof(pa)));
587
588 Fprintf(stderr, " from %s",
589 inet_ntop(AF_INET6, &saddr.sin6_addr, pa, sizeof(pa)));
590 Fprintf(stderr, ", %d hops max, %d byte packets\n", max_ttl, datalen);
591 (void) fflush(stderr);
592
593 for (ttl = 1; ttl <= max_ttl; ++ttl) {
594 struct in6_addr lastaddr = {{{0,}}};
595 int got_there = 0;
596 int unreachable = 0;
597
598 Printf("%2d ", ttl);
599 for (probe = 0; probe < nprobes; ++probe) {
600 int cc, reset_timer;
601 struct timeval t1, t2;
602 struct timezone tz;
603 struct in6_addr to;
604
605 gettimeofday(&t1, &tz);
606 send_probe(++seq, ttl);
607 reset_timer = 1;
608
609 while ((cc = wait_for_reply(icmp_sock, &from, &to, reset_timer)) != 0) {
610 gettimeofday(&t2, &tz);
611 if ((i = packet_ok(packet, cc, &from, &to, seq, &t1))) {
612 reset_timer = 1;
613 if (memcmp(&from.sin6_addr, &lastaddr, sizeof(from.sin6_addr))) {
614 print(packet, cc, &from);
615 memcpy(&lastaddr,
616 &from.sin6_addr,
617 sizeof(lastaddr));
618 }
619 Printf(" %g ms", deltaT(&t1, &t2));
620 switch(i - 1) {
621 case ICMP6_DST_UNREACH_NOPORT:
622 ++got_there;
623 break;
624
625 case ICMP6_DST_UNREACH_NOROUTE:
626 ++unreachable;
627 Printf(" !N");
628 break;
629 case ICMP6_DST_UNREACH_ADDR:
630 ++unreachable;
631 Printf(" !H");
632 break;
633
634 case ICMP6_DST_UNREACH_ADMIN:
635 ++unreachable;
636 Printf(" !S");
637 break;
638 }
639 break;
640 } else
641 reset_timer = 0;
642 }
643 if (cc <= 0)
644 Printf(" *");
645 (void) fflush(stdout);
646 }
647 putchar('\n');
648 if (got_there ||
649 (unreachable > 0 && unreachable >= nprobes-1))
650 exit(0);
651 }
652
653 return 0;
654 }
655
656 int
wait_for_reply(sock,from,to,reset_timer)657 wait_for_reply(sock, from, to, reset_timer)
658 int sock;
659 struct sockaddr_in6 *from;
660 struct in6_addr *to;
661 int reset_timer;
662 {
663 fd_set fds;
664 static struct timeval wait;
665 int cc = 0;
666 char cbuf[512];
667
668 FD_ZERO(&fds);
669 FD_SET(sock, &fds);
670 if (reset_timer) {
671 /*
672 * traceroute could hang if someone else has a ping
673 * running and our ICMP reply gets dropped but we don't
674 * realize it because we keep waking up to handle those
675 * other ICMP packets that keep coming in. To fix this,
676 * "reset_timer" will only be true if the last packet that
677 * came in was for us or if this is the first time we're
678 * waiting for a reply since sending out a probe. Note
679 * that this takes advantage of the select() feature on
680 * Linux where the remaining timeout is written to the
681 * struct timeval area.
682 */
683 wait.tv_sec = waittime;
684 wait.tv_usec = 0;
685 }
686
687 if (select(sock+1, &fds, (fd_set *)0, (fd_set *)0, &wait) > 0) {
688 struct iovec iov;
689 struct msghdr msg;
690 iov.iov_base = packet;
691 iov.iov_len = sizeof(packet);
692 msg.msg_name = (void *)from;
693 msg.msg_namelen = sizeof(*from);
694 msg.msg_iov = &iov;
695 msg.msg_iovlen = 1;
696 msg.msg_flags = 0;
697 msg.msg_control = cbuf;
698 msg.msg_controllen = sizeof(cbuf);
699
700 cc = recvmsg(icmp_sock, &msg, 0);
701 if (cc >= 0) {
702 struct cmsghdr *cmsg;
703 struct in6_pktinfo *ipi;
704
705 for (cmsg = CMSG_FIRSTHDR(&msg);
706 cmsg;
707 cmsg = CMSG_NXTHDR(&msg, cmsg)) {
708 if (cmsg->cmsg_level != SOL_IPV6)
709 continue;
710 switch (cmsg->cmsg_type) {
711 case IPV6_PKTINFO:
712 #ifdef IPV6_2292PKTINFO
713 case IPV6_2292PKTINFO:
714 #endif
715 ipi = (struct in6_pktinfo *)CMSG_DATA(cmsg);
716 memcpy(to, ipi, sizeof(*to));
717 }
718 }
719 }
720 }
721
722 return(cc);
723 }
724
725
send_probe(int seq,int ttl)726 void send_probe(int seq, int ttl)
727 {
728 struct pkt_format *pkt = (struct pkt_format *) sendbuff;
729 int i;
730
731 pkt->ident = htonl(ident);
732 pkt->seq = htonl(seq);
733 gettimeofday(&pkt->tv, &tz);
734
735 i = setsockopt(sndsock, SOL_IPV6, IPV6_UNICAST_HOPS, &ttl, sizeof(ttl));
736 if (i < 0)
737 {
738 perror("setsockopt");
739 exit(1);
740 }
741
742 do {
743 i = sendto(sndsock, sendbuff, datalen, 0,
744 (struct sockaddr *)&whereto, sizeof(whereto));
745 } while (i<0 && errno == ECONNREFUSED);
746
747 if (i < 0 || i != datalen) {
748 if (i<0)
749 perror("sendto");
750 Printf("traceroute: wrote %s %d chars, ret=%d\n", hostname,
751 datalen, i);
752 (void) fflush(stdout);
753 }
754 }
755
756
deltaT(struct timeval * t1p,struct timeval * t2p)757 double deltaT(struct timeval *t1p, struct timeval *t2p)
758 {
759 register double dt;
760
761 dt = (double)(t2p->tv_sec - t1p->tv_sec) * 1000.0 +
762 (double)(t2p->tv_usec - t1p->tv_usec) / 1000.0;
763 return (dt);
764 }
765
766
767 /*
768 * Convert an ICMP "type" field to a printable string.
769 */
pr_type(unsigned char t)770 char * pr_type(unsigned char t)
771 {
772 switch(t) {
773 /* Unknown */
774 case 0:
775 return "Error";
776 case 1:
777 /* ICMP6_DST_UNREACH: */
778 return "Destination Unreachable";
779 case 2:
780 /* ICMP6_PACKET_TOO_BIG: */
781 return "Packet Too Big";
782 case 3:
783 /* ICMP6_TIME_EXCEEDED */
784 return "Time Exceeded in Transit";
785 case 4:
786 /* ICMP6_PARAM_PROB */
787 return "Parameter Problem";
788 case 128:
789 /* ICMP6_ECHO_REQUEST */
790 return "Echo Request";
791 case 129:
792 /* ICMP6_ECHO_REPLY */
793 return "Echo Reply";
794 case 130:
795 /* ICMP6_MEMBERSHIP_QUERY */
796 return "Membership Query";
797 case 131:
798 /* ICMP6_MEMBERSHIP_REPORT */
799 return "Membership Report";
800 case 132:
801 /* ICMP6_MEMBERSHIP_REDUCTION */
802 return "Membership Reduction";
803 case 133:
804 /* ND_ROUTER_SOLICIT */
805 return "Router Solicitation";
806 case 134:
807 /* ND_ROUTER_ADVERT */
808 return "Router Advertisement";
809 case 135:
810 /* ND_NEIGHBOR_SOLICIT */
811 return "Neighbor Solicitation";
812 case 136:
813 /* ND_NEIGHBOR_ADVERT */
814 return "Neighbor Advertisement";
815 case 137:
816 /* ND_REDIRECT */
817 return "Redirect";
818 }
819
820 return("OUT-OF-RANGE");
821 }
822
823
packet_ok(u_char * buf,int cc,struct sockaddr_in6 * from,struct in6_addr * to,int seq,struct timeval * tv)824 int packet_ok(u_char *buf, int cc, struct sockaddr_in6 *from,
825 struct in6_addr *to, int seq,
826 struct timeval *tv)
827 {
828 struct icmp6_hdr *icp;
829 u_char type, code;
830
831 icp = (struct icmp6_hdr *) buf;
832
833 type = icp->icmp6_type;
834 code = icp->icmp6_code;
835
836 if ((type == ICMP6_TIME_EXCEEDED && code == ICMP6_TIME_EXCEED_TRANSIT) ||
837 type == ICMP6_DST_UNREACH)
838 {
839 struct ip6_hdr *hip;
840 struct udphdr *up;
841 int nexthdr;
842
843 hip = (struct ip6_hdr *) (icp + 1);
844 up = (struct udphdr *)(hip+1);
845 nexthdr = hip->ip6_nxt;
846
847 if (nexthdr == 44) {
848 nexthdr = *(unsigned char*)up;
849 up++;
850 }
851 if (nexthdr == IPPROTO_UDP)
852 {
853 struct pkt_format *pkt;
854
855 pkt = (struct pkt_format *) (up + 1);
856
857 if (ntohl(pkt->ident) == ident &&
858 ntohl(pkt->seq) == seq)
859 {
860 *tv = pkt->tv;
861 return (type == ICMP6_TIME_EXCEEDED ? -1 : code+1);
862 }
863 }
864
865 }
866
867 if (verbose) {
868 unsigned char *p;
869 char pa1[MAX_HOSTNAMELEN];
870 char pa2[MAX_HOSTNAMELEN];
871 int i;
872
873 p = (unsigned char *) (icp + 1);
874
875 Printf("\n%d bytes from %s to %s", cc,
876 inet_ntop(AF_INET6, &from->sin6_addr, pa1, sizeof(pa1)),
877 inet_ntop(AF_INET6, to, pa2, sizeof(pa2)));
878
879 Printf(": icmp type %d (%s) code %d\n", type, pr_type(type),
880 icp->icmp6_code);
881
882 cc -= sizeof(struct icmp6_hdr);
883 for (i = 0; i < cc ; i++) {
884 if (i % 16 == 0)
885 Printf("%04x:", i);
886 if (i % 4 == 0)
887 Printf(" ");
888 Printf("%02x", 0xff & (unsigned)p[i]);
889 if (i % 16 == 15 && i + 1 < cc)
890 Printf("\n");
891 }
892 Printf("\n");
893 }
894
895 return(0);
896 }
897
898
print(unsigned char * buf,int cc,struct sockaddr_in6 * from)899 void print(unsigned char *buf, int cc, struct sockaddr_in6 *from)
900 {
901 char pa[MAX_HOSTNAMELEN];
902
903 if (nflag)
904 Printf(" %s", inet_ntop(AF_INET6, &from->sin6_addr,
905 pa, sizeof(pa)));
906 else
907 {
908 const char *hostname;
909 struct hostent *hp;
910 char *s = NULL;
911
912 hostname = inet_ntop(AF_INET6, &from->sin6_addr, pa, sizeof(pa));
913
914 if ((hp = gethostbyaddr((char *)&from->sin6_addr,
915 sizeof(from->sin6_addr), AF_INET6))) {
916 #ifdef USE_IDN
917 if (idna_to_unicode_lzlz(hp->h_name, &s, 0) != IDNA_SUCCESS)
918 s = NULL;
919 #endif
920 }
921
922 Printf(" %s (%s)", hp ? (s ? s : hp->h_name) : hostname, pa);
923
924 free(s);
925 }
926 }
927
928
929 /*
930 * Subtract 2 timeval structs: out = out - in.
931 * Out is assumed to be >= in.
932 */
933 void
tvsub(out,in)934 tvsub(out, in)
935 register struct timeval *out, *in;
936 {
937 if ((out->tv_usec -= in->tv_usec) < 0) {
938 out->tv_sec--;
939 out->tv_usec += 1000000;
940 }
941 out->tv_sec -= in->tv_sec;
942 }
943
usage(void)944 void usage(void)
945 {
946 fprintf(stderr,
947 "Usage: traceroute6 [-dnrvV] [-m max_ttl] [-p port#] [-q nqueries]\n\t\
948 [-s src_addr] [-t tos] [-w wait] host [data size]\n");
949 exit(1);
950 }
951