projects / unix-history / blame
? search:
summary | tags | clone url | shortlog | log | commit | commitdiff | tree
blob | blame (incremental) | history | HEAD
fix -e compat flag; a few compilation warnings; improve error messages
[unix-history] / usr / src / usr.sbin / traceroute / traceroute.c
CommitLineData
d7ff4848
KB		 1/*-
2 * Copyright (c) 1990 The Regents of the University of California.
3 * All rights reserved.
4 *
5 * This code is derived from software contributed to Berkeley by
6 * Van Jacobson.
7 *
8 * %sccs.include.redist.c%
9 */
10
14d700c5 11#ifndef lint
d7ff4848
KB		 12char copyright[] =
13"@(#) Copyright (c) 1990 The Regents of the University of California.\n\
14 All rights reserved.\n";
15#endif /* not lint */
16
17#ifndef lint
c2ae755c 18static char sccsid[] = "@(#)traceroute.c 5.5 (Berkeley) %G%";
d7ff4848 19#endif /* not lint */
14d700c5
KB		 20
21/*
22 * traceroute host - trace the route ip packets follow going to "host".
23 *
24 * Attempt to trace the route an ip packet would follow to some
25 * internet host. We find out intermediate hops by launching probe
26 * packets with a small ttl (time to live) then listening for an
27 * icmp "time exceeded" reply from a gateway. We start our probes
28 * with a ttl of one and increase by one until we get an icmp "port
29 * unreachable" (which means we got to "host") or hit a max (which
30 * defaults to 30 hops & can be changed with the -m flag). Three
31 * probes (change with -q flag) are sent at each ttl setting and a
32 * line is printed showing the ttl, address of the gateway and
33 * round trip time of each probe. If the probe answers come from
34 * different gateways, the address of each responding system will
35 * be printed. If there is no response within a 5 sec. timeout
36 * interval (changed with the -w flag), a "*" is printed for that
37 * probe.
38 *
39 * Probe packets are UDP format. We don't want the destination
40 * host to process them so the destination port is set to an
41 * unlikely value (if some clod on the destination is using that
42 * value, it can be changed with the -p flag).
43 *
44 * A sample use might be:
45 *
46 * [yak 71]% traceroute nis.nsf.net.
47 * traceroute to nis.nsf.net (35.1.1.48), 30 hops max, 56 byte packet
48 * 1 helios.ee.lbl.gov (128.3.112.1) 19 ms 19 ms 0 ms
49 * 2 lilac-dmc.Berkeley.EDU (128.32.216.1) 39 ms 39 ms 19 ms
50 * 3 lilac-dmc.Berkeley.EDU (128.32.216.1) 39 ms 39 ms 19 ms
51 * 4 ccngw-ner-cc.Berkeley.EDU (128.32.136.23) 39 ms 40 ms 39 ms
52 * 5 ccn-nerif22.Berkeley.EDU (128.32.168.22) 39 ms 39 ms 39 ms
53 * 6 128.32.197.4 (128.32.197.4) 40 ms 59 ms 59 ms
54 * 7 131.119.2.5 (131.119.2.5) 59 ms 59 ms 59 ms
55 * 8 129.140.70.13 (129.140.70.13) 99 ms 99 ms 80 ms
56 * 9 129.140.71.6 (129.140.71.6) 139 ms 239 ms 319 ms
57 * 10 129.140.81.7 (129.140.81.7) 220 ms 199 ms 199 ms
58 * 11 nic.merit.edu (35.1.1.48) 239 ms 239 ms 239 ms
59 *
60 * Note that lines 2 & 3 are the same. This is due to a buggy
61 * kernel on the 2nd hop system -- lbl-csam.arpa -- that forwards
62 * packets with a zero ttl.
63 *
64 * A more interesting example is:
65 *
66 * [yak 72]% traceroute allspice.lcs.mit.edu.
67 * traceroute to allspice.lcs.mit.edu (18.26.0.115), 30 hops max
68 * 1 helios.ee.lbl.gov (128.3.112.1) 0 ms 0 ms 0 ms
69 * 2 lilac-dmc.Berkeley.EDU (128.32.216.1) 19 ms 19 ms 19 ms
70 * 3 lilac-dmc.Berkeley.EDU (128.32.216.1) 39 ms 19 ms 19 ms
71 * 4 ccngw-ner-cc.Berkeley.EDU (128.32.136.23) 19 ms 39 ms 39 ms
72 * 5 ccn-nerif22.Berkeley.EDU (128.32.168.22) 20 ms 39 ms 39 ms
73 * 6 128.32.197.4 (128.32.197.4) 59 ms 119 ms 39 ms
74 * 7 131.119.2.5 (131.119.2.5) 59 ms 59 ms 39 ms
75 * 8 129.140.70.13 (129.140.70.13) 80 ms 79 ms 99 ms
76 * 9 129.140.71.6 (129.140.71.6) 139 ms 139 ms 159 ms
77 * 10 129.140.81.7 (129.140.81.7) 199 ms 180 ms 300 ms
78 * 11 129.140.72.17 (129.140.72.17) 300 ms 239 ms 239 ms
79 * 12 * * *
80 * 13 128.121.54.72 (128.121.54.72) 259 ms 499 ms 279 ms
81 * 14 * * *
82 * 15 * * *
83 * 16 * * *
84 * 17 * * *
85 * 18 ALLSPICE.LCS.MIT.EDU (18.26.0.115) 339 ms 279 ms 279 ms
86 *
87 * (I start to see why I'm having so much trouble with mail to
88 * MIT.) Note that the gateways 12, 14, 15, 16 & 17 hops away
89 * either don't send ICMP "time exceeded" messages or send them
90 * with a ttl too small to reach us. 14 - 17 are running the
91 * MIT C Gateway code that doesn't send "time exceeded"s. God
92 * only knows what's going on with 12.
93 *
94 * The silent gateway 12 in the above may be the result of a bug in
95 * the 4.[23]BSD network code (and its derivatives): 4.x (x <= 3)
96 * sends an unreachable message using whatever ttl remains in the
97 * original datagram. Since, for gateways, the remaining ttl is
98 * zero, the icmp "time exceeded" is guaranteed to not make it back
99 * to us. The behavior of this bug is slightly more interesting
100 * when it appears on the destination system:
101 *
102 * 1 helios.ee.lbl.gov (128.3.112.1) 0 ms 0 ms 0 ms
103 * 2 lilac-dmc.Berkeley.EDU (128.32.216.1) 39 ms 19 ms 39 ms
104 * 3 lilac-dmc.Berkeley.EDU (128.32.216.1) 19 ms 39 ms 19 ms
105 * 4 ccngw-ner-cc.Berkeley.EDU (128.32.136.23) 39 ms 40 ms 19 ms
106 * 5 ccn-nerif35.Berkeley.EDU (128.32.168.35) 39 ms 39 ms 39 ms
107 * 6 csgw.Berkeley.EDU (128.32.133.254) 39 ms 59 ms 39 ms
108 * 7 * * *
109 * 8 * * *
110 * 9 * * *
111 * 10 * * *
112 * 11 * * *
113 * 12 * * *
114 * 13 rip.Berkeley.EDU (128.32.131.22) 59 ms ! 39 ms ! 39 ms !
115 *
116 * Notice that there are 12 "gateways" (13 is the final
117 * destination) and exactly the last half of them are "missing".
118 * What's really happening is that rip (a Sun-3 running Sun OS3.5)
119 * is using the ttl from our arriving datagram as the ttl in its
120 * icmp reply. So, the reply will time out on the return path
121 * (with no notice sent to anyone since icmp's aren't sent for
122 * icmp's) until we probe with a ttl that's at least twice the path
123 * length. I.e., rip is really only 7 hops away. A reply that
124 * returns with a ttl of 1 is a clue this problem exists.
125 * Traceroute prints a "!" after the time if the ttl is <= 1.
126 * Since vendors ship a lot of obsolete (DEC's Ultrix, Sun 3.x) or
127 * non-standard (HPUX) software, expect to see this problem
128 * frequently and/or take care picking the target host of your
129 * probes.
130 *
131 * Other possible annotations after the time are !H, !N, !P (got a host,
132 * network or protocol unreachable, respectively), !S or !F (source
133 * route failed or fragmentation needed -- neither of these should
134 * ever occur and the associated gateway is busted if you see one). If
135 * almost all the probes result in some kind of unreachable, traceroute
136 * will give up and exit.
137 *
138 * Notes
139 * -----
140 * This program must be run by root or be setuid. (I suggest that
141 * you *don't* make it setuid -- casual use could result in a lot
142 * of unnecessary traffic on our poor, congested nets.)
143 *
144 * This program requires a kernel mod that does not appear in any
145 * system available from Berkeley: A raw ip socket using proto
146 * IPPROTO_RAW must interpret the data sent as an ip datagram (as
147 * opposed to data to be wrapped in a ip datagram). See the README
148 * file that came with the source to this program for a description
149 * of the mods I made to /sys/netinet/raw_ip.c. Your mileage may
150 * vary. But, again, ANY 4.x (x < 4) BSD KERNEL WILL HAVE TO BE
151 * MODIFIED TO RUN THIS PROGRAM.
152 *
153 * The udp port usage may appear bizarre (well, ok, it is bizarre).
154 * The problem is that an icmp message only contains 8 bytes of
155 * data from the original datagram. 8 bytes is the size of a udp
156 * header so, if we want to associate replies with the original
157 * datagram, the necessary information must be encoded into the
158 * udp header (the ip id could be used but there's no way to
159 * interlock with the kernel's assignment of ip id's and, anyway,
160 * it would have taken a lot more kernel hacking to allow this
161 * code to set the ip id). So, to allow two or more users to
162 * use traceroute simultaneously, we use this task's pid as the
163 * source port (the high bit is set to move the port number out
164 * of the "likely" range). To keep track of which probe is being
165 * replied to (so times and/or hop counts don't get confused by a
166 * reply that was delayed in transit), we increment the destination
167 * port number before each probe.
168 *
169 * Don't use this as a coding example. I was trying to find a
170 * routing problem and this code sort-of popped out after 48 hours
171 * without sleep. I was amazed it ever compiled, much less ran.
172 *
173 * I stole the idea for this program from Steve Deering. Since
174 * the first release, I've learned that had I attended the right
175 * IETF working group meetings, I also could have stolen it from Guy
176 * Almes or Matt Mathis. I don't know (or care) who came up with
177 * the idea first. I envy the originators' perspicacity and I'm
178 * glad they didn't keep the idea a secret.
179 *
180 * Tim Seaver, Ken Adelman and C. Philip Wood provided bug fixes and/or
181 * enhancements to the original distribution.
182 *
183 * I've hacked up a round-trip-route version of this that works by
184 * sending a loose-source-routed udp datagram through the destination
185 * back to yourself. Unfortunately, SO many gateways botch source
186 * routing, the thing is almost worthless. Maybe one day...
187 *
188 * -- Van Jacobson (van@helios.ee.lbl.gov)
189 * Tue Dec 20 03:50:13 PST 1988
14d700c5
KB		 190 */
191
14d700c5 192#include <sys/param.h>
38dde0cd 193#include <sys/time.h>
14d700c5
KB		 194#include <sys/socket.h>
195#include <sys/file.h>
196#include <sys/ioctl.h>
197
198#include <netinet/in_systm.h>
199#include <netinet/in.h>
200#include <netinet/ip.h>
201#include <netinet/ip_icmp.h>
202#include <netinet/udp.h>
14d700c5 203
c2ae755c
KB		 204#include <arpa/inet.h>
205
206#include <netdb.h>
38dde0cd
KB		 207#include <stdio.h>
208#include <errno.h>
c2ae755c 209#include <stdlib.h>
38dde0cd 210#include <string.h>
c2ae755c 211#include <unistd.h>
38dde0cd 212
14d700c5
KB		 213#define MAXPACKET 65535 /* max ip packet size */
214#ifndef MAXHOSTNAMELEN
215#define MAXHOSTNAMELEN 64
216#endif
217
218#ifndef FD_SET
219#define NFDBITS (8*sizeof(fd_set))
220#define FD_SETSIZE NFDBITS
221#define FD_SET(n, p) ((p)->fds_bits[(n)/NFDBITS] |= (1 << ((n) % NFDBITS)))
222#define FD_CLR(n, p) ((p)->fds_bits[(n)/NFDBITS] &= ~(1 << ((n) % NFDBITS)))
223#define FD_ISSET(n, p) ((p)->fds_bits[(n)/NFDBITS] & (1 << ((n) % NFDBITS)))
224#define FD_ZERO(p) bzero((char *)(p), sizeof(*(p)))
225#endif
226
227#define Fprintf (void)fprintf
228#define Sprintf (void)sprintf
229#define Printf (void)printf
14d700c5
KB		 230
231/*
232 * format of a (udp) probe packet.
233 */
234struct opacket {
235 struct ip ip;
236 struct udphdr udp;
237 u_char seq; /* sequence number of this packet */
238 u_char ttl; /* ttl packet left with */
239 struct timeval tv; /* time packet left */
240};
241
242u_char packet[512]; /* last inbound (icmp) packet */
243struct opacket *outpacket; /* last output (udp) packet */
c2ae755c
KB		 244
245int wait_for_reply __P((int, struct sockaddr_in *));
246void send_probe __P((int, int));
247double deltaT __P((struct timeval *, struct timeval *));
248int packet_ok __P((u_char *, int, struct sockaddr_in *, int));
249void print __P((u_char *, int, struct sockaddr_in *));
250void tvsub __P((struct timeval *, struct timeval *));
251char *inetname __P((struct in_addr));
252void usage __P(());
14d700c5
KB		 253
254int s; /* receive (icmp) socket file descriptor */
255int sndsock; /* send (udp) socket file descriptor */
256struct timezone tz; /* leftover */
257
258struct sockaddr whereto; /* Who to try to reach */
259int datalen; /* How much data */
260
261char *source = 0;
262char *hostname;
14d700c5
KB		 263
264int nprobes = 3;
265int max_ttl = 30;
266u_short ident;
267u_short port = 32768+666; /* start udp dest port # for probe packets */
14d700c5
KB		 268int options; /* socket options */
269int verbose;
270int waittime = 5; /* time to wait for response (in seconds) */
271int nflag; /* print addresses numerically */
272
c2ae755c 273int
14d700c5 274main(argc, argv)
c2ae755c 275 int argc;
14d700c5
KB		 276 char *argv[];
277{
636bde93
KB		 278 extern char *optarg;
279 extern int optind;
14d700c5 280 struct hostent *hp;
636bde93
KB		 281 struct protoent *pe;
282 struct sockaddr_in from, *to;
283 int ch, i, on, probe, seq, tos, ttl;
284
285 on = 1;
286 seq = tos = 0;
287 to = (struct sockaddr_in *)&whereto;
288 while ((ch = getopt(argc, argv, "dm:np:q:rs:t:w:v")) != EOF)
289 switch(ch) {
290 case 'd':
291 options |= SO_DEBUG;
292 break;
293 case 'm':
294 max_ttl = atoi(optarg);
295 if (max_ttl <= 1) {
296 Fprintf(stderr,
297 "traceroute: max ttl must be >1.\n");
298 exit(1);
14d700c5 299 }
636bde93
KB		 300 break;
301 case 'n':
302 nflag++;
303 break;
304 case 'p':
305 port = atoi(optarg);
306 if (port < 1) {
307 Fprintf(stderr,
308 "traceroute: port must be >0.\n");
309 exit(1);
310 }
311 break;
312 case 'q':
313 nprobes = atoi(optarg);
314 if (nprobes < 1) {
315 Fprintf(stderr,
316 "traceroute: nprobes must be >0.\n");
317 exit(1);
318 }
319 break;
320 case 'r':
321 options |= SO_DONTROUTE;
322 break;
323 case 's':
324 /*
325 * set the ip source address of the outbound
326 * probe (e.g., on a multi-homed host).
327 */
328 source = optarg;
329 break;
330 case 't':
331 tos = atoi(optarg);
332 if (tos < 0 || tos > 255) {
333 Fprintf(stderr,
334 "traceroute: tos must be 0 to 255.\n");
335 exit(1);
336 }
337 break;
338 case 'v':
339 verbose++;
340 break;
341 case 'w':
342 waittime = atoi(optarg);
343 if (waittime <= 1) {
344 Fprintf(stderr,
345 "traceroute: wait must be >1 sec.\n");
346 exit(1);
347 }
348 break;
349 default:
350 usage();
351 }
352 argc -= optind;
353 argv += optind;
354
c2ae755c 355 if (argc < 1)
636bde93
KB		 356 usage();
357
14d700c5
KB		 358 setlinebuf (stdout);
359
360 (void) bzero((char *)&whereto, sizeof(struct sockaddr));
361 to->sin_family = AF_INET;
636bde93 362 to->sin_addr.s_addr = inet_addr(*argv);
c2ae755c 363 if (to->sin_addr.s_addr != -1)
636bde93
KB		 364 hostname = *argv;
365 else {
366 hp = gethostbyname(*argv);
14d700c5
KB		 367 if (hp) {
368 to->sin_family = hp->h_addrtype;
369 bcopy(hp->h_addr, (caddr_t)&to->sin_addr, hp->h_length);
370 hostname = hp->h_name;
371 } else {
636bde93
KB		 372 (void)fprintf(stderr,
373 "traceroute: unknown host %s\n", *argv);
14d700c5
KB		 374 exit(1);
375 }
376 }
c2ae755c 377 if (*++argv)
636bde93 378 datalen = atoi(*argv);
14d700c5 379 if (datalen < 0 || datalen >= MAXPACKET - sizeof(struct opacket)) {
636bde93
KB		 380 Fprintf(stderr,
381 "traceroute: packet size must be 0 <= s < %ld.\n",
382 MAXPACKET - sizeof(struct opacket));
14d700c5
KB		 383 exit(1);
384 }
385 datalen += sizeof(struct opacket);
386 outpacket = (struct opacket *)malloc((unsigned)datalen);
387 if (! outpacket) {
388 perror("traceroute: malloc");
389 exit(1);
390 }
391 (void) bzero((char *)outpacket, datalen);
392 outpacket->ip.ip_dst = to->sin_addr;
393 outpacket->ip.ip_tos = tos;
394
395 ident = (getpid() & 0xffff) | 0x8000;
396
397 if ((pe = getprotobyname("icmp")) == NULL) {
398 Fprintf(stderr, "icmp: unknown protocol\n");
399 exit(10);
400 }
401 if ((s = socket(AF_INET, SOCK_RAW, pe->p_proto)) < 0) {
402 perror("traceroute: icmp socket");
403 exit(5);
404 }
405 if (options & SO_DEBUG)
406 (void) setsockopt(s, SOL_SOCKET, SO_DEBUG,
407 (char *)&on, sizeof(on));
408 if (options & SO_DONTROUTE)
409 (void) setsockopt(s, SOL_SOCKET, SO_DONTROUTE,
410 (char *)&on, sizeof(on));
411
412 if ((sndsock = socket(AF_INET, SOCK_RAW, IPPROTO_RAW)) < 0) {
413 perror("traceroute: raw socket");
414 exit(5);
415 }
416#ifdef SO_SNDBUF
417 if (setsockopt(sndsock, SOL_SOCKET, SO_SNDBUF, (char *)&datalen,
418 sizeof(datalen)) < 0) {
419 perror("traceroute: SO_SNDBUF");
420 exit(6);
421 }
422#endif SO_SNDBUF
423#ifdef IP_HDRINCL
424 if (setsockopt(sndsock, IPPROTO_IP, IP_HDRINCL, (char *)&on,
425 sizeof(on)) < 0) {
426 perror("traceroute: IP_HDRINCL");
427 exit(6);
428 }
429#endif IP_HDRINCL
430 if (options & SO_DEBUG)
431 (void) setsockopt(sndsock, SOL_SOCKET, SO_DEBUG,
432 (char *)&on, sizeof(on));
433 if (options & SO_DONTROUTE)
434 (void) setsockopt(sndsock, SOL_SOCKET, SO_DONTROUTE,
435 (char *)&on, sizeof(on));
436
437 if (source) {
438 (void) bzero((char *)&from, sizeof(struct sockaddr));
439 from.sin_family = AF_INET;
440 from.sin_addr.s_addr = inet_addr(source);
441 if (from.sin_addr.s_addr == -1) {
442 Printf("traceroute: unknown host %s\n", source);
443 exit(1);
444 }
445 outpacket->ip.ip_src = from.sin_addr;
446#ifndef IP_HDRINCL
447 if (bind(sndsock, (struct sockaddr *)&from, sizeof(from)) < 0) {
448 perror ("traceroute: bind:");
449 exit (1);
450 }
451#endif IP_HDRINCL
452 }
453
454 Fprintf(stderr, "traceroute to %s (%s)", hostname,
455 inet_ntoa(to->sin_addr));
456 if (source)
457 Fprintf(stderr, " from %s", source);
458 Fprintf(stderr, ", %d hops max, %d byte packets\n", max_ttl, datalen);
459 (void) fflush(stderr);
460
461 for (ttl = 1; ttl <= max_ttl; ++ttl) {
462 u_long lastaddr = 0;
463 int got_there = 0;
464 int unreachable = 0;
465
466 Printf("%2d ", ttl);
467 for (probe = 0; probe < nprobes; ++probe) {
468 int cc;
c2ae755c
KB		 469 struct timeval t1, t2;
470 struct timezone tz;
14d700c5
KB		 471 struct ip *ip;
472
c2ae755c 473 (void) gettimeofday(&t1, &tz);
14d700c5
KB		 474 send_probe(++seq, ttl);
475 while (cc = wait_for_reply(s, &from)) {
c2ae755c 476 (void) gettimeofday(&t2, &tz);
14d700c5 477 if ((i = packet_ok(packet, cc, &from, seq))) {
14d700c5
KB		 478 if (from.sin_addr.s_addr != lastaddr) {
479 print(packet, cc, &from);
480 lastaddr = from.sin_addr.s_addr;
481 }
c2ae755c 482 Printf(" %g ms", deltaT(&t1, &t2));
14d700c5
KB		 483 switch(i - 1) {
484 case ICMP_UNREACH_PORT:
485#ifndef ARCHAIC
486 ip = (struct ip *)packet;
487 if (ip->ip_ttl <= 1)
488 Printf(" !");
489#endif ARCHAIC
490 ++got_there;
491 break;
492 case ICMP_UNREACH_NET:
493 ++unreachable;
494 Printf(" !N");
495 break;
496 case ICMP_UNREACH_HOST:
497 ++unreachable;
498 Printf(" !H");
499 break;
500 case ICMP_UNREACH_PROTOCOL:
501 ++got_there;
502 Printf(" !P");
503 break;
504 case ICMP_UNREACH_NEEDFRAG:
505 ++unreachable;
506 Printf(" !F");
507 break;
508 case ICMP_UNREACH_SRCFAIL:
509 ++unreachable;
510 Printf(" !S");
511 break;
512 }
513 break;
514 }
515 }
516 if (cc == 0)
517 Printf(" *");
518 (void) fflush(stdout);
519 }
520 putchar('\n');
521 if (got_there || unreachable >= nprobes-1)
522 exit(0);
523 }
524}
525
c2ae755c 526int
14d700c5
KB		 527wait_for_reply(sock, from)
528 int sock;
529 struct sockaddr_in *from;
530{
531 fd_set fds;
532 struct timeval wait;
533 int cc = 0;
534 int fromlen = sizeof (*from);
535
536 FD_ZERO(&fds);
537 FD_SET(sock, &fds);
538 wait.tv_sec = waittime; wait.tv_usec = 0;
539
540 if (select(sock+1, &fds, (fd_set *)0, (fd_set *)0, &wait) > 0)
541 cc=recvfrom(s, (char *)packet, sizeof(packet), 0,
542 (struct sockaddr *)from, &fromlen);
543
544 return(cc);
545}
546
547
c2ae755c 548void
14d700c5 549send_probe(seq, ttl)
c2ae755c 550 int seq, ttl;
14d700c5
KB		 551{
552 struct opacket *op = outpacket;
553 struct ip *ip = &op->ip;
554 struct udphdr *up = &op->udp;
555 int i;
556
557 ip->ip_off = 0;
558 ip->ip_p = IPPROTO_UDP;
559 ip->ip_len = datalen;
560 ip->ip_ttl = ttl;
561
562 up->uh_sport = htons(ident);
563 up->uh_dport = htons(port+seq);
564 up->uh_ulen = htons((u_short)(datalen - sizeof(struct ip)));
565 up->uh_sum = 0;
566
567 op->seq = seq;
568 op->ttl = ttl;
569 (void) gettimeofday(&op->tv, &tz);
570
571 i = sendto(sndsock, (char *)outpacket, datalen, 0, &whereto,
572 sizeof(struct sockaddr));
573 if (i < 0 || i != datalen) {
574 if (i<0)
575 perror("sendto");
576 Printf("traceroute: wrote %s %d chars, ret=%d\n", hostname,
577 datalen, i);
578 (void) fflush(stdout);
579 }
580}
581
582
c2ae755c
KB		 583double
584deltaT(t1p, t2p)
585 struct timeval *t1p, *t2p;
14d700c5 586{
c2ae755c 587 register double dt;
14d700c5 588
c2ae755c
KB		 589 dt = (double)(t2p->tv_sec - t1p->tv_sec) * 1000.0 +
590 (double)(t2p->tv_usec - t1p->tv_usec) / 1000.0;
591 return (dt);
14d700c5
KB		 592}
593
594
595/*
596 * Convert an ICMP "type" field to a printable string.
597 */
598char *
599pr_type(t)
600 u_char t;
601{
602 static char *ttab[] = {
603 "Echo Reply", "ICMP 1", "ICMP 2", "Dest Unreachable",
604 "Source Quench", "Redirect", "ICMP 6", "ICMP 7",
605 "Echo", "ICMP 9", "ICMP 10", "Time Exceeded",
606 "Param Problem", "Timestamp", "Timestamp Reply", "Info Request",
607 "Info Reply"
608 };
609
610 if(t > 16)
611 return("OUT-OF-RANGE");
612
613 return(ttab[t]);
614}
615
616
c2ae755c 617int
14d700c5
KB		 618packet_ok(buf, cc, from, seq)
619 u_char *buf;
620 int cc;
621 struct sockaddr_in *from;
622 int seq;
623{
624 register struct icmp *icp;
625 u_char type, code;
626 int hlen;
627#ifndef ARCHAIC
628 struct ip *ip;
629
630 ip = (struct ip *) buf;
631 hlen = ip->ip_hl << 2;
632 if (cc < hlen + ICMP_MINLEN) {
633 if (verbose)
634 Printf("packet too short (%d bytes) from %s\n", cc,
635 inet_ntoa(from->sin_addr));
636 return (0);
637 }
638 cc -= hlen;
639 icp = (struct icmp *)(buf + hlen);
640#else
641 icp = (struct icmp *)buf;
642#endif ARCHAIC
643 type = icp->icmp_type; code = icp->icmp_code;
644 if ((type == ICMP_TIMXCEED && code == ICMP_TIMXCEED_INTRANS) ||
645 type == ICMP_UNREACH) {
646 struct ip *hip;
647 struct udphdr *up;
648
649 hip = &icp->icmp_ip;
650 hlen = hip->ip_hl << 2;
651 up = (struct udphdr *)((u_char *)hip + hlen);
652 if (hlen + 12 <= cc && hip->ip_p == IPPROTO_UDP &&
653 up->uh_sport == htons(ident) &&
654 up->uh_dport == htons(port+seq))
655 return (type == ICMP_TIMXCEED? -1 : code+1);
656 }
657#ifndef ARCHAIC
658 if (verbose) {
659 int i;
660 u_long *lp = (u_long *)&icp->icmp_ip;
661
662 Printf("\n%d bytes from %s to %s", cc,
663 inet_ntoa(from->sin_addr), inet_ntoa(ip->ip_dst));
664 Printf(": icmp type %d (%s) code %d\n", type, pr_type(type),
665 icp->icmp_code);
666 for (i = 4; i < cc ; i += sizeof(long))
667 Printf("%2d: x%8.8lx\n", i, *lp++);
668 }
669#endif ARCHAIC
670 return(0);
671}
672
673
c2ae755c 674void
14d700c5
KB		 675print(buf, cc, from)
676 u_char *buf;
677 int cc;
678 struct sockaddr_in *from;
679{
680 struct ip *ip;
681 int hlen;
682
683 ip = (struct ip *) buf;
684 hlen = ip->ip_hl << 2;
685 cc -= hlen;
686
687 if (nflag)
688 Printf(" %s", inet_ntoa(from->sin_addr));
689 else
690 Printf(" %s (%s)", inetname(from->sin_addr),
691 inet_ntoa(from->sin_addr));
692
693 if (verbose)
694 Printf (" %d bytes to %s", cc, inet_ntoa (ip->ip_dst));
695}
696
697
698#ifdef notyet
699/*
700 * Checksum routine for Internet Protocol family headers (C Version)
701 */
c2ae755c 702u_short
14d700c5 703in_cksum(addr, len)
c2ae755c
KB		 704 u_short *addr;
705 int len;
14d700c5
KB		 706{
707 register int nleft = len;
708 register u_short *w = addr;
709 register u_short answer;
710 register int sum = 0;
711
712 /*
713 * Our algorithm is simple, using a 32 bit accumulator (sum),
714 * we add sequential 16 bit words to it, and at the end, fold
715 * back all the carry bits from the top 16 bits into the lower
716 * 16 bits.
717 */
718 while (nleft > 1) {
719 sum += *w++;
720 nleft -= 2;
721 }
722
723 /* mop up an odd byte, if necessary */
724 if (nleft == 1)
725 sum += *(u_char *)w;
726
727 /*
728 * add back carry outs from top 16 bits to low 16 bits
729 */
730 sum = (sum >> 16) + (sum & 0xffff); /* add hi 16 to low 16 */
731 sum += (sum >> 16); /* add carry */
732 answer = ~sum; /* truncate to 16 bits */
733 return (answer);
734}
735#endif notyet
736
737/*
738 * Subtract 2 timeval structs: out = out - in.
739 * Out is assumed to be >= in.
740 */
c2ae755c 741void
14d700c5 742tvsub(out, in)
c2ae755c 743 register struct timeval *out, *in;
14d700c5
KB		 744{
745 if ((out->tv_usec -= in->tv_usec) < 0) {
746 out->tv_sec--;
747 out->tv_usec += 1000000;
748 }
749 out->tv_sec -= in->tv_sec;
750}
751
752
753/*
754 * Construct an Internet address representation.
c2ae755c 755 * If the nflag has been supplied, give
14d700c5
KB		 756 * numeric value, otherwise try for symbolic name.
757 */
758char *
759inetname(in)
760 struct in_addr in;
761{
762 register char *cp;
763 static char line[50];
764 struct hostent *hp;
765 static char domain[MAXHOSTNAMELEN + 1];
766 static int first = 1;
767
768 if (first && !nflag) {
769 first = 0;
770 if (gethostname(domain, MAXHOSTNAMELEN) == 0 &&
771 (cp = index(domain, '.')))
772 (void) strcpy(domain, cp + 1);
773 else
774 domain[0] = 0;
775 }
776 cp = 0;
777 if (!nflag && in.s_addr != INADDR_ANY) {
778 hp = gethostbyaddr((char *)&in, sizeof (in), AF_INET);
779 if (hp) {
780 if ((cp = index(hp->h_name, '.')) &&
781 !strcmp(cp + 1, domain))
782 *cp = 0;
783 cp = hp->h_name;
784 }
785 }
786 if (cp)
787 (void) strcpy(line, cp);
788 else {
789 in.s_addr = ntohl(in.s_addr);
790#define C(x) ((x) & 0xff)
791 Sprintf(line, "%lu.%lu.%lu.%lu", C(in.s_addr >> 24),
792 C(in.s_addr >> 16), C(in.s_addr >> 8), C(in.s_addr));
793 }
794 return (line);
795}
636bde93 796
c2ae755c 797void
636bde93
KB		 798usage()
799{
c2ae755c 800 (void)fprintf(stderr,
636bde93
KB		 801"usage: traceroute [-dnrv] [-m max_ttl] [-p port#] [-q nqueries]\n\t\
802[-s src_addr] [-t tos] [-w wait] host [data size]\n");
803 exit(1);
804}
Continuous source code history from original PDP-7 UNIX to FreeBSD 2, the first fully unencumbered FreeBSD release.