1 /* $OpenBSD: traceroute.c,v 1.61 2004/01/26 18:23:51 deraadt Exp $ */
2 /* $NetBSD: traceroute.c,v 1.10 1995/05/21 15:50:45 mycroft Exp $ */
5 * Copyright (c) 1990, 1993
6 * The Regents of the University of California. All rights reserved.
8 * This code is derived from software contributed to Berkeley by
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in the
18 * documentation and/or other materials provided with the distribution.
19 * 3. Neither the name of the University nor the names of its contributors
20 * may be used to endorse or promote products derived from this software
21 * without specific prior written permission.
23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35 * $DragonFly: src/usr.sbin/traceroute/traceroute.c,v 1.9 2007/10/25 08:12:42 hasso Exp $
36 * @(#)traceroute.c 8.1 (Berkeley) 6/6/93
40 * traceroute host - trace the route ip packets follow going to "host".
42 * Attempt to trace the route an ip packet would follow to some
43 * internet host. We find out intermediate hops by launching probe
44 * packets with a small ttl (time to live) then listening for an
45 * icmp "time exceeded" reply from a gateway. We start our probes
46 * with a ttl of one and increase by one until we get an icmp "port
47 * unreachable" (which means we got to "host") or hit a max (which
48 * defaults to 64 hops & can be changed with the -m flag). Three
49 * probes (change with -q flag) are sent at each ttl setting and a
50 * line is printed showing the ttl, address of the gateway and
51 * round trip time of each probe. If the probe answers come from
52 * different gateways, the address of each responding system will
53 * be printed. If there is no response within a 5 sec. timeout
54 * interval (changed with the -w flag), a "*" is printed for that
57 * Probe packets are UDP format. We don't want the destination
58 * host to process them so the destination port is set to an
59 * unlikely value (if some clod on the destination is using that
60 * value, it can be changed with the -p flag).
62 * A sample use might be:
64 * [yak 71]% traceroute nis.nsf.net.
65 * traceroute to nis.nsf.net (35.1.1.48), 64 hops max, 56 byte packet
66 * 1 helios.ee.lbl.gov (128.3.112.1) 19 ms 19 ms 0 ms
67 * 2 lilac-dmc.Berkeley.EDU (128.32.216.1) 39 ms 39 ms 19 ms
68 * 3 lilac-dmc.Berkeley.EDU (128.32.216.1) 39 ms 39 ms 19 ms
69 * 4 ccngw-ner-cc.Berkeley.EDU (128.32.136.23) 39 ms 40 ms 39 ms
70 * 5 ccn-nerif22.Berkeley.EDU (128.32.168.22) 39 ms 39 ms 39 ms
71 * 6 128.32.197.4 (128.32.197.4) 40 ms 59 ms 59 ms
72 * 7 131.119.2.5 (131.119.2.5) 59 ms 59 ms 59 ms
73 * 8 129.140.70.13 (129.140.70.13) 99 ms 99 ms 80 ms
74 * 9 129.140.71.6 (129.140.71.6) 139 ms 239 ms 319 ms
75 * 10 129.140.81.7 (129.140.81.7) 220 ms 199 ms 199 ms
76 * 11 nic.merit.edu (35.1.1.48) 239 ms 239 ms 239 ms
78 * Note that lines 2 & 3 are the same. This is due to a buggy
79 * kernel on the 2nd hop system -- lbl-csam.arpa -- that forwards
80 * packets with a zero ttl.
82 * A more interesting example is:
84 * [yak 72]% traceroute allspice.lcs.mit.edu.
85 * traceroute to allspice.lcs.mit.edu (18.26.0.115), 64 hops max
86 * 1 helios.ee.lbl.gov (128.3.112.1) 0 ms 0 ms 0 ms
87 * 2 lilac-dmc.Berkeley.EDU (128.32.216.1) 19 ms 19 ms 19 ms
88 * 3 lilac-dmc.Berkeley.EDU (128.32.216.1) 39 ms 19 ms 19 ms
89 * 4 ccngw-ner-cc.Berkeley.EDU (128.32.136.23) 19 ms 39 ms 39 ms
90 * 5 ccn-nerif22.Berkeley.EDU (128.32.168.22) 20 ms 39 ms 39 ms
91 * 6 128.32.197.4 (128.32.197.4) 59 ms 119 ms 39 ms
92 * 7 131.119.2.5 (131.119.2.5) 59 ms 59 ms 39 ms
93 * 8 129.140.70.13 (129.140.70.13) 80 ms 79 ms 99 ms
94 * 9 129.140.71.6 (129.140.71.6) 139 ms 139 ms 159 ms
95 * 10 129.140.81.7 (129.140.81.7) 199 ms 180 ms 300 ms
96 * 11 129.140.72.17 (129.140.72.17) 300 ms 239 ms 239 ms
98 * 13 128.121.54.72 (128.121.54.72) 259 ms 499 ms 279 ms
103 * 18 ALLSPICE.LCS.MIT.EDU (18.26.0.115) 339 ms 279 ms 279 ms
105 * (I start to see why I'm having so much trouble with mail to
106 * MIT.) Note that the gateways 12, 14, 15, 16 & 17 hops away
107 * either don't send ICMP "time exceeded" messages or send them
108 * with a ttl too small to reach us. 14 - 17 are running the
109 * MIT C Gateway code that doesn't send "time exceeded"s. God
110 * only knows what's going on with 12.
112 * The silent gateway 12 in the above may be the result of a bug in
113 * the 4.[23]BSD network code (and its derivatives): 4.x (x <= 3)
114 * sends an unreachable message using whatever ttl remains in the
115 * original datagram. Since, for gateways, the remaining ttl is
116 * zero, the icmp "time exceeded" is guaranteed to not make it back
117 * to us. The behavior of this bug is slightly more interesting
118 * when it appears on the destination system:
120 * 1 helios.ee.lbl.gov (128.3.112.1) 0 ms 0 ms 0 ms
121 * 2 lilac-dmc.Berkeley.EDU (128.32.216.1) 39 ms 19 ms 39 ms
122 * 3 lilac-dmc.Berkeley.EDU (128.32.216.1) 19 ms 39 ms 19 ms
123 * 4 ccngw-ner-cc.Berkeley.EDU (128.32.136.23) 39 ms 40 ms 19 ms
124 * 5 ccn-nerif35.Berkeley.EDU (128.32.168.35) 39 ms 39 ms 39 ms
125 * 6 csgw.Berkeley.EDU (128.32.133.254) 39 ms 59 ms 39 ms
132 * 13 rip.Berkeley.EDU (128.32.131.22) 59 ms ! 39 ms ! 39 ms !
134 * Notice that there are 12 "gateways" (13 is the final
135 * destination) and exactly the last half of them are "missing".
136 * What's really happening is that rip (a Sun-3 running Sun OS3.5)
137 * is using the ttl from our arriving datagram as the ttl in its
138 * icmp reply. So, the reply will time out on the return path
139 * (with no notice sent to anyone since icmp's aren't sent for
140 * icmp's) until we probe with a ttl that's at least twice the path
141 * length. I.e., rip is really only 7 hops away. A reply that
142 * returns with a ttl of 1 is a clue this problem exists.
143 * Traceroute prints a "!" after the time if the ttl is <= 1.
144 * Since vendors ship a lot of obsolete (DEC's Ultrix, Sun 3.x) or
145 * non-standard (HPUX) software, expect to see this problem
146 * frequently and/or take care picking the target host of your
149 * Other possible annotations after the time are !H, !N, !P (got a host,
150 * network or protocol unreachable, respectively), !S or !F (source
151 * route failed or fragmentation needed -- neither of these should
152 * ever occur and the associated gateway is busted if you see one). If
153 * almost all the probes result in some kind of unreachable, traceroute
154 * will give up and exit.
158 * This program must be run by root or be setuid. (I suggest that
159 * you *don't* make it setuid -- casual use could result in a lot
160 * of unnecessary traffic on our poor, congested nets.)
162 * This program requires a kernel mod that does not appear in any
163 * system available from Berkeley: A raw ip socket using proto
164 * IPPROTO_RAW must interpret the data sent as an ip datagram (as
165 * opposed to data to be wrapped in a ip datagram). See the README
166 * file that came with the source to this program for a description
167 * of the mods I made to /sys/netinet/raw_ip.c. Your mileage may
168 * vary. But, again, ANY 4.x (x < 4) BSD KERNEL WILL HAVE TO BE
169 * MODIFIED TO RUN THIS PROGRAM.
171 * The udp port usage may appear bizarre (well, ok, it is bizarre).
172 * The problem is that an icmp message only contains 8 bytes of
173 * data from the original datagram. 8 bytes is the size of a udp
174 * header so, if we want to associate replies with the original
175 * datagram, the necessary information must be encoded into the
176 * udp header (the ip id could be used but there's no way to
177 * interlock with the kernel's assignment of ip id's and, anyway,
178 * it would have taken a lot more kernel hacking to allow this
179 * code to set the ip id). So, to allow two or more users to
180 * use traceroute simultaneously, we use this task's pid as the
181 * source port (the high bit is set to move the port number out
182 * of the "likely" range). To keep track of which probe is being
183 * replied to (so times and/or hop counts don't get confused by a
184 * reply that was delayed in transit), we increment the destination
185 * port number before each probe.
187 * Don't use this as a coding example. I was trying to find a
188 * routing problem and this code sort-of popped out after 48 hours
189 * without sleep. I was amazed it ever compiled, much less ran.
191 * I stole the idea for this program from Steve Deering. Since
192 * the first release, I've learned that had I attended the right
193 * IETF working group meetings, I also could have stolen it from Guy
194 * Almes or Matt Mathis. I don't know (or care) who came up with
195 * the idea first. I envy the originators' perspicacity and I'm
196 * glad they didn't keep the idea a secret.
198 * Tim Seaver, Ken Adelman and C. Philip Wood provided bug fixes and/or
199 * enhancements to the original distribution.
201 * I've hacked up a round-trip-route version of this that works by
202 * sending a loose-source-routed udp datagram through the destination
203 * back to yourself. Unfortunately, SO many gateways botch source
204 * routing, the thing is almost worthless. Maybe one day...
206 * -- Van Jacobson (van@helios.ee.lbl.gov)
207 * Tue Dec 20 03:50:13 PST 1988
210 #include <sys/param.h>
211 #include <sys/time.h>
212 #include <sys/socket.h>
213 #include <sys/file.h>
214 #include <sys/ioctl.h>
215 #include <sys/sysctl.h>
217 #include <netinet/in_systm.h>
218 #include <netinet/in.h>
219 #include <netinet/ip.h>
220 #include <netinet/ip_icmp.h>
221 #include <netinet/ip_var.h>
222 #include <netinet/udp.h>
224 #include <arpa/inet.h>
235 #define MAX_LSRR ((MAX_IPOPTLEN - 4) / 4)
238 * Format of the data in a (udp) probe packet.
241 u_char seq
; /* sequence number of this packet */
242 u_int8_t ttl
; /* ttl packet left with */
243 u_int32_t sec
; /* time packet left */
248 * Support for ICMP extensions - RFC4950.
250 #define ICMP_EXT_OFFSET 8 + 128 /* ICMP type, code, checksum (unused)
251 * + original datagram */
252 #define ICMP_EXT_VERSION 2
254 /* ICMP Extension Header according to RFC4884. */
255 #define EXT_VERSION(x) (((x) & 0xf0000000) >> 28)
256 #define EXT_CHECKSUM(x) ((x) & 0x0000ffff)
259 * ICMP extensions, object header
261 struct icmp_ext_obj_hdr
{
264 #define MPLS_STACK_ENTRY_CLASS 1
266 #define MPLS_STACK_ENTRY_C_TYPE 1
269 /* MPLS Label Stack Object. */
270 #define MPLS_LABEL(x) (((x) & 0xfffff000) >> 12)
271 #define MPLS_EXP(x) (((x) & 0x00000e00) >> 9)
272 #define MPLS_STACK(x) (((x) & 0x00000100) >> 8)
273 #define MPLS_TTL(x) ((x) & 0x000000ff)
275 struct in_addr gateway
[MAX_LSRR
+ 1];
278 int32_t usec_perturb
;
280 u_char packet
[512], *outpacket
; /* last inbound (icmp) packet */
282 void decode_extensions(unsigned char *, int);
283 void dump_packet(void);
284 int wait_for_reply(int, struct sockaddr_in
*, struct timeval
*);
285 void send_probe(int, u_int8_t
, int, struct sockaddr_in
*);
286 int packet_ok(u_char
*, int, struct sockaddr_in
*, int, int);
287 const char *pr_type(u_int8_t
);
288 void print(u_char
*, int, struct sockaddr_in
*);
289 char *inetname(struct in_addr
);
290 u_short
in_cksum(u_short
*, int);
293 int s
; /* receive (icmp) socket file descriptor */
294 int sndsock
; /* send (udp) socket file descriptor */
296 int datalen
; /* How much data */
297 int headerlen
; /* How long packet's header is */
303 u_int8_t max_ttl
= IPDEFTTL
;
304 u_int8_t first_ttl
= 1;
306 u_short port
= 32768+666; /* start udp dest port # for probe packets */
307 u_char proto
= IPPROTO_UDP
;
308 u_int8_t icmp_type
= ICMP_ECHO
; /* default ICMP code/type */
309 u_char icmp_code
= 0;
310 int options
; /* socket options */
312 int waittime
= 5; /* time to wait for response (in seconds) */
313 int nflag
; /* print addresses numerically */
315 int Mflag
; /* show MPLS labels if any */
318 main(int argc
, char *argv
[])
320 int mib
[4] = { CTL_NET
, PF_INET
, IPPROTO_IP
, IPCTL_DEFTTL
};
321 int ttl_flag
= 0, incflag
= 1, protoset
= 0, sump
= 0;
322 int ch
, i
, lsrr
= 0, on
= 1, probe
, seq
= 0, tos
= 0;
323 size_t size
= sizeof(max_ttl
);
324 struct sockaddr_in from
, to
;
332 if ((s
= socket(AF_INET
, SOCK_RAW
, IPPROTO_ICMP
)) < 0)
333 err(5, "icmp socket");
334 if ((sndsock
= socket(AF_INET
, SOCK_RAW
, IPPROTO_RAW
)) < 0)
335 err(5, "raw socket");
341 sysctl(mib
, sizeof(mib
)/sizeof(mib
[0]), &max_ttl
, &size
, NULL
, 0);
343 while ((ch
= getopt(argc
, argv
, "SDIdg:f:m:np:q:rs:t:w:vlP:cM")) != -1)
351 l
= strtol(optarg
, &ep
, 10);
352 if (errno
|| !*optarg
|| *ep
|| l
< 1 || l
> max_ttl
)
353 errx(1, "min ttl must be 1 to %u.", max_ttl
);
354 first_ttl
= (u_int8_t
)l
;
366 if (lsrr
>= MAX_LSRR
)
367 errx(1, "too many gateways; max %d", MAX_LSRR
);
368 if (inet_aton(optarg
, &gateway
[lsrr
]) == 0) {
369 hp
= gethostbyname(optarg
);
371 errx(1, "unknown host %s", optarg
);
372 memcpy(&gateway
[lsrr
], hp
->h_addr
, hp
->h_length
);
380 errx(1, "protocol already set with -P");
382 proto
= IPPROTO_ICMP
;
390 l
= strtol(optarg
, &ep
, 10);
391 if (errno
|| !*optarg
|| *ep
|| l
< first_ttl
||
393 errx(1, "max ttl must be %u to %u.", first_ttl
,
395 max_ttl
= (u_int8_t
)l
;
406 l
= strtol(optarg
, &ep
, 10);
407 if (errno
|| !*optarg
|| *ep
|| l
<= 0 || l
>= 65536)
408 errx(1, "port must be >0, <65536.");
413 errx(1, "protocol already set with -I");
417 l
= strtol(optarg
, &ep
, 10);
418 if (errno
|| !*optarg
|| *ep
|| l
< 1 ||
420 struct protoent
*pent
;
422 pent
= getprotobyname(optarg
);
424 proto
= pent
->p_proto
;
426 errx(1, "proto must be >=1, or a name.");
433 l
= strtol(optarg
, &ep
, 10);
434 if (errno
|| !*optarg
|| *ep
|| l
< 1 || l
> INT_MAX
)
435 errx(1, "nprobes must be >0.");
439 options
|= SO_DONTROUTE
;
443 * set the ip source address of the outbound
444 * probe (e.g., on a multi-homed host).
451 l
= strtol(optarg
, &ep
, 10);
452 if (errno
|| !*optarg
|| *ep
|| l
< 0 || l
> 255)
453 errx(1, "tos must be 0 to 255.");
462 l
= strtol(optarg
, &ep
, 10);
463 if (errno
|| !*optarg
|| *ep
|| l
<= 1 || l
> INT_MAX
)
464 errx(1, "wait must be >1 sec.");
478 memset(&to
, 0, sizeof(struct sockaddr
));
479 to
.sin_family
= AF_INET
;
480 if (inet_aton(*argv
, &to
.sin_addr
) != 0)
483 hp
= gethostbyname(*argv
);
485 errx(1, "unknown host %s", *argv
);
486 to
.sin_family
= hp
->h_addrtype
;
487 memcpy(&to
.sin_addr
, hp
->h_addr
, hp
->h_length
);
488 if ((hostname
= strdup(hp
->h_name
)) == NULL
)
490 if (hp
->h_addr_list
[1] != NULL
)
491 warnx("Warning: %s has multiple addresses; using %s",
492 hostname
, inet_ntoa(to
.sin_addr
));
497 l
= strtol(*argv
, &ep
, 10);
498 if (errno
|| !*argv
|| *ep
|| l
< 0 || l
> INT_MAX
)
499 errx(1, "datalen out of range");
505 headerlen
= (sizeof(struct ip
) + lsrrlen
+
506 sizeof(struct udphdr
) + sizeof(struct packetdata
));
509 headerlen
= (sizeof(struct ip
) + lsrrlen
+
510 sizeof(struct icmp
) + sizeof(struct packetdata
));
513 headerlen
= (sizeof(struct ip
) + lsrrlen
+
514 sizeof(struct packetdata
));
517 if (datalen
< 0 || datalen
> IP_MAXPACKET
- headerlen
)
518 errx(1, "packet size must be 0 to %d.",
519 IP_MAXPACKET
- headerlen
);
521 datalen
+= headerlen
;
523 outpacket
= (u_char
*)malloc(datalen
);
524 if (outpacket
== NULL
)
526 memset(outpacket
, 0, datalen
);
528 ip
= (struct ip
*)outpacket
;
530 u_char
*p
= (u_char
*)(ip
+ 1);
536 gateway
[lsrr
] = to
.sin_addr
;
537 for (i
= 1; i
<= lsrr
; i
++) {
538 memcpy(p
, &gateway
[i
], sizeof(struct in_addr
));
539 p
+= sizeof(struct in_addr
);
541 ip
->ip_dst
= gateway
[0];
543 ip
->ip_dst
= to
.sin_addr
;
544 ip
->ip_off
= htons(0);
545 ip
->ip_hl
= (sizeof(struct ip
) + lsrrlen
) >> 2;
547 ip
->ip_v
= IPVERSION
;
550 ident
= (getpid() & 0xffff) | 0x8000;
551 tmprnd
= arc4random();
552 sec_perturb
= (tmprnd
& 0x80000000) ? -(tmprnd
& 0x7ff) :
554 usec_perturb
= arc4random();
556 if (options
& SO_DEBUG
)
557 setsockopt(s
, SOL_SOCKET
, SO_DEBUG
, (char *)&on
, sizeof(on
));
559 if (setsockopt(sndsock
, SOL_SOCKET
, SO_SNDBUF
, (char *)&datalen
,
560 sizeof(datalen
)) < 0)
562 #endif /* SO_SNDBUF */
564 if (setsockopt(sndsock
, IPPROTO_IP
, IP_HDRINCL
, (char *)&on
,
566 err(6, "IP_HDRINCL");
567 #endif /* IP_HDRINCL */
568 if (options
& SO_DEBUG
)
569 setsockopt(sndsock
, SOL_SOCKET
, SO_DEBUG
,
570 (char *)&on
, sizeof(on
));
571 if (options
& SO_DONTROUTE
)
572 setsockopt(sndsock
, SOL_SOCKET
, SO_DONTROUTE
,
573 (char *)&on
, sizeof(on
));
576 memset(&from
, 0, sizeof(struct sockaddr
));
577 from
.sin_family
= AF_INET
;
578 if (inet_aton(source
, &from
.sin_addr
) == 0)
579 errx(1, "unknown host %s", source
);
580 ip
->ip_src
= from
.sin_addr
;
582 (ntohl(from
.sin_addr
.s_addr
) & 0xff000000U
) == 0x7f000000U
&&
583 (ntohl(to
.sin_addr
.s_addr
) & 0xff000000U
) != 0x7f000000U
)
584 errx(1, "source is on 127/8, destination is not");
587 bind(sndsock
, (struct sockaddr
*)&from
, sizeof(from
)) < 0)
591 fprintf(stderr
, "traceroute to %s (%s)", hostname
,
592 inet_ntoa(to
.sin_addr
));
594 fprintf(stderr
, " from %s", source
);
595 fprintf(stderr
, ", %u hops max, %d byte packets\n", max_ttl
, datalen
);
599 printf("Skipping %u intermediate hops\n", first_ttl
- 1);
601 for (ttl
= first_ttl
; ttl
<= max_ttl
; ++ttl
) {
602 int got_there
= 0, unreachable
= 0, timeout
= 0, loss
;
604 in_addr_t lastaddr
= 0;
608 for (probe
= 0, loss
= 0; probe
< nprobes
; ++probe
) {
610 struct timeval t1
, t2
;
613 gettimeofday(&t1
, NULL
);
614 send_probe(++seq
, ttl
, incflag
, &to
);
615 while ((cc
= wait_for_reply(s
, &from
, &t1
))) {
616 gettimeofday(&t2
, NULL
);
617 if (t2
.tv_sec
- t1
.tv_sec
> waittime
) {
621 i
= packet_ok(packet
, cc
, &from
, seq
, incflag
);
622 /* Skip short packet */
626 from
.sin_addr
.s_addr
!= lastaddr
) {
629 print(packet
, cc
, &from
);
630 lastaddr
= from
.sin_addr
.s_addr
;
633 dt
= (quad_t
)(t2
.tv_sec
- t1
.tv_sec
) * 1000000 +
634 (quad_t
)(t2
.tv_usec
- t1
.tv_usec
);
635 printf(" %u", (u_int
)(dt
/ 1000));
637 printf(".%u", (u_int
)(dt
% 1000));
639 ip
= (struct ip
*)packet
;
641 printf(" (%u)", ip
->ip_ttl
);
644 ip
= (struct ip
*)packet
;
651 /* time exceeded in transit */
656 case ICMP_UNREACH_PORT
:
658 ip
= (struct ip
*)packet
;
664 case ICMP_UNREACH_NET
:
668 case ICMP_UNREACH_HOST
:
672 case ICMP_UNREACH_PROTOCOL
:
676 case ICMP_UNREACH_NEEDFRAG
:
680 case ICMP_UNREACH_SRCFAIL
:
684 case ICMP_UNREACH_FILTER_PROHIB
:
688 case ICMP_UNREACH_NET_PROHIB
: /*misuse*/
692 case ICMP_UNREACH_HOST_PROHIB
:
696 case ICMP_UNREACH_NET_UNKNOWN
:
697 case ICMP_UNREACH_HOST_UNKNOWN
:
701 case ICMP_UNREACH_ISOLATED
:
705 case ICMP_UNREACH_TOSNET
:
706 case ICMP_UNREACH_TOSHOST
:
712 printf(" !<%d>", i
- 1);
722 else if (cc
&& probe
== nprobes
- 1 && Mflag
)
723 decode_extensions(packet
, cc
);
727 printf(" (%d%% loss)", (loss
* 100) / nprobes
);
729 if (got_there
|| (unreachable
&& (unreachable
+ timeout
) >= nprobes
))
736 wait_for_reply(int sock
, struct sockaddr_in
*from
, struct timeval
*sent
)
738 socklen_t fromlen
= sizeof (*from
);
739 struct timeval now
, wait
;
743 fdsn
= howmany(sock
+1, NFDBITS
) * sizeof(fd_mask
);
744 if ((fdsp
= (fd_set
*)malloc(fdsn
)) == NULL
)
746 memset(fdsp
, 0, fdsn
);
748 gettimeofday(&now
, NULL
);
749 wait
.tv_sec
= (sent
->tv_sec
+ waittime
) - now
.tv_sec
;
750 wait
.tv_usec
= sent
->tv_usec
- now
.tv_usec
;
751 if (wait
.tv_usec
< 0) {
752 wait
.tv_usec
+= 1000000;
756 wait
.tv_sec
= wait
.tv_usec
= 0;
758 if (select(sock
+1, fdsp
, (fd_set
*)0, (fd_set
*)0, &wait
) > 0)
759 cc
= recvfrom(s
, (char *)packet
, sizeof(packet
), 0,
760 (struct sockaddr
*)from
, &fromlen
);
767 decode_extensions(unsigned char *buf
, int ip_len
)
770 struct icmp_ext_obj_hdr
*obj_hdr
;
772 int data_len
, obj_len
;
775 ip
= (struct ip
*)buf
;
777 if (ip_len
<= (int)(sizeof(struct ip
) + ICMP_EXT_OFFSET
)) {
779 * No support for ICMP extensions on this host
785 * Move forward to the start of the ICMP extensions, if present
787 buf
+= (ip
->ip_hl
<< 2) + ICMP_EXT_OFFSET
;
788 cmn_hdr
= (uint32_t *)buf
;
790 if (EXT_VERSION(ntohl(*cmn_hdr
)) != ICMP_EXT_VERSION
) {
797 data_len
= ip_len
- ((u_char
*)cmn_hdr
- (u_char
*)ip
);
800 * Check the checksum, cmn_hdr->checksum == 0 means no checksum'ing
803 * If the checksum is ok, we'll get 0, as the checksum is calculated
804 * with the checksum field being 0'd.
806 if (EXT_CHECKSUM(ntohl(*cmn_hdr
)) &&
807 in_cksum((u_short
*)cmn_hdr
, data_len
)) {
811 buf
+= sizeof(*cmn_hdr
);
812 data_len
-= sizeof(*cmn_hdr
);
814 while (data_len
>= (int)sizeof(struct icmp_ext_obj_hdr
)) {
815 unsigned char *nextbuf
;
817 obj_hdr
= (struct icmp_ext_obj_hdr
*)buf
;
818 obj_len
= ntohs(obj_hdr
->length
);
821 * Sanity check the length field
823 if (obj_len
< (int)sizeof(*obj_hdr
) || obj_len
> data_len
)
826 /* Object has to be 4-byte aligned. */
830 nextbuf
= buf
+ obj_len
;
834 * Move past the object header
836 buf
+= sizeof(struct icmp_ext_obj_hdr
);
837 obj_len
-= sizeof(struct icmp_ext_obj_hdr
);
839 switch (obj_hdr
->class_num
) {
840 case MPLS_STACK_ENTRY_CLASS
:
841 switch (obj_hdr
->c_type
) {
842 case MPLS_STACK_ENTRY_C_TYPE
:
843 while (obj_len
>= (int)sizeof(uint32_t)) {
844 mpls_hdr
= ntohl(*(uint32_t *)buf
);
846 buf
+= sizeof(uint32_t);
847 obj_len
-= sizeof(uint32_t);
848 printf(" [MPLS: Label %d Exp %d]",
849 MPLS_LABEL(mpls_hdr
),
854 * Something went wrong, and we're at
855 * a unknown offset into the packet,
856 * ditch the rest of it.
863 * Unknown object, skip past it
872 * Unknown object, skip past it
886 fprintf(stderr
, "packet data:");
887 for (p
= outpacket
, i
= 0; i
< datalen
; i
++) {
889 fprintf(stderr
, "\n ");
890 fprintf(stderr
, " %02x", *p
++);
892 fprintf(stderr
, "\n");
896 send_probe(int seq
, u_int8_t ttl
, int iflag
, struct sockaddr_in
*to
)
898 struct ip
*ip
= (struct ip
*)outpacket
;
899 u_char
*p
= (u_char
*)(ip
+ 1);
900 struct udphdr
*up
= (struct udphdr
*)(p
+ lsrrlen
);
901 struct icmp
*icmpp
= (struct icmp
*)(p
+ lsrrlen
);
902 struct packetdata
*op
;
906 ip
->ip_len
= datalen
;
908 ip
->ip_id
= htons(ident
+seq
);
912 icmpp
->icmp_type
= icmp_type
;
913 icmpp
->icmp_code
= icmp_code
;
914 icmpp
->icmp_seq
= htons(seq
);
915 icmpp
->icmp_id
= htons(ident
);
916 op
= (struct packetdata
*)(icmpp
+ 1);
919 up
->uh_sport
= htons(ident
);
921 up
->uh_dport
= htons(port
+seq
);
923 up
->uh_dport
= htons(port
);
924 up
->uh_ulen
= htons((u_short
)(datalen
- sizeof(struct ip
) -
927 op
= (struct packetdata
*)(up
+ 1);
930 op
= (struct packetdata
*)(ip
+ 1);
937 * We don't want hostiles snooping the net to get any useful
938 * information about us. Send the timestamp in network byte order,
939 * and perturb the timestamp enough that they won't know our
940 * real clock ticker. We don't want to perturb the time by too
941 * much: being off by a suspiciously large amount might indicate
944 * The timestamps in the packet are currently unused. If future
945 * work wants to use them they will have to subtract out the
946 * perturbation first.
948 gettimeofday(&tv
, NULL
);
949 op
->sec
= htonl(tv
.tv_sec
+ sec_perturb
);
950 op
->usec
= htonl((tv
.tv_usec
+ usec_perturb
) % 1000000);
952 if (proto
== IPPROTO_ICMP
&& icmp_type
== ICMP_ECHO
) {
953 icmpp
->icmp_cksum
= 0;
954 icmpp
->icmp_cksum
= in_cksum((u_short
*)icmpp
,
955 datalen
- sizeof(struct ip
) - lsrrlen
);
956 if (icmpp
->icmp_cksum
== 0)
957 icmpp
->icmp_cksum
= 0xffff;
963 i
= sendto(sndsock
, outpacket
, datalen
, 0, (struct sockaddr
*)to
,
964 sizeof(struct sockaddr_in
));
965 if (i
< 0 || i
!= datalen
) {
968 printf("traceroute: wrote %s %d chars, ret=%d\n", hostname
,
974 static const char *ttab
[] = {
997 * Convert an ICMP "type" field to a printable string.
1003 return ("OUT-OF-RANGE");
1008 packet_ok(u_char
*buf
, int cc
, struct sockaddr_in
*from
, int seq
, int iflag
)
1017 ip
= (struct ip
*) buf
;
1018 hlen
= ip
->ip_hl
<< 2;
1019 if (cc
< hlen
+ ICMP_MINLEN
) {
1021 printf("packet too short (%d bytes) from %s\n", cc
,
1022 inet_ntoa(from
->sin_addr
));
1026 icp
= (struct icmp
*)(buf
+ hlen
);
1028 icp
= (struct icmp
*)buf
;
1029 #endif /* ARCHAIC */
1030 type
= icp
->icmp_type
;
1031 code
= icp
->icmp_code
;
1032 if ((type
== ICMP_TIMXCEED
&& code
== ICMP_TIMXCEED_INTRANS
) ||
1033 type
== ICMP_UNREACH
|| type
== ICMP_ECHOREPLY
) {
1038 hip
= &icp
->icmp_ip
;
1039 hlen
= hip
->ip_hl
<< 2;
1043 if (icmp_type
== ICMP_ECHO
&&
1044 type
== ICMP_ECHOREPLY
&&
1045 icp
->icmp_id
== htons(ident
) &&
1046 icp
->icmp_seq
== htons(seq
))
1047 return (-2); /* we got there */
1049 icmpp
= (struct icmp
*)((u_char
*)hip
+ hlen
);
1050 if (hlen
+ 8 <= cc
&& hip
->ip_p
== IPPROTO_ICMP
&&
1051 icmpp
->icmp_id
== htons(ident
) &&
1052 icmpp
->icmp_seq
== htons(seq
))
1053 return (type
== ICMP_TIMXCEED
? -1 : code
+ 1);
1057 up
= (struct udphdr
*)((u_char
*)hip
+ hlen
);
1058 if (hlen
+ 12 <= cc
&& hip
->ip_p
== proto
&&
1059 up
->uh_sport
== htons(ident
) &&
1060 ((iflag
&& up
->uh_dport
== htons(port
+ seq
)) ||
1061 (!iflag
&& up
->uh_dport
== htons(port
))))
1062 return (type
== ICMP_TIMXCEED
? -1 : code
+ 1);
1065 /* this is some odd, user specified proto,
1066 * how do we check it?
1068 if (hip
->ip_p
== proto
)
1069 return (type
== ICMP_TIMXCEED
? -1 : code
+ 1);
1075 in_addr_t
*lp
= (in_addr_t
*)&icp
->icmp_ip
;
1077 printf("\n%d bytes from %s", cc
, inet_ntoa(from
->sin_addr
));
1078 printf(" to %s", inet_ntoa(ip
->ip_dst
));
1079 printf(": icmp type %u (%s) code %d\n", type
, pr_type(type
),
1081 for (i
= 4; i
< cc
; i
+= sizeof(in_addr_t
))
1082 printf("%2d: x%8.8lx\n", i
, (unsigned long)*lp
++);
1084 #endif /* ARCHAIC */
1089 print(u_char
*buf
, int cc
, struct sockaddr_in
*from
)
1094 ip
= (struct ip
*) buf
;
1095 hlen
= ip
->ip_hl
<< 2;
1099 printf(" %s", inet_ntoa(from
->sin_addr
));
1101 printf(" %s (%s)", inetname(from
->sin_addr
),
1102 inet_ntoa(from
->sin_addr
));
1105 printf(" %d bytes to %s", cc
, inet_ntoa (ip
->ip_dst
));
1110 * Checksum routine for Internet Protocol family headers (C Version)
1113 in_cksum(u_short
*addr
, int len
)
1115 u_short
*w
= addr
, answer
;
1116 int nleft
= len
, sum
= 0;
1119 * Our algorithm is simple, using a 32 bit accumulator (sum),
1120 * we add sequential 16 bit words to it, and at the end, fold
1121 * back all the carry bits from the top 16 bits into the lower
1129 /* mop up an odd byte, if necessary */
1131 sum
+= *(u_char
*)w
;
1134 * add back carry outs from top 16 bits to low 16 bits
1136 sum
= (sum
>> 16) + (sum
& 0xffff); /* add hi 16 to low 16 */
1137 sum
+= (sum
>> 16); /* add carry */
1138 answer
= ~sum
; /* truncate to 16 bits */
1143 * Construct an Internet address representation.
1144 * If the nflag has been supplied, give
1145 * numeric value, otherwise try for symbolic name.
1148 inetname(struct in_addr in
)
1150 static char domain
[MAXHOSTNAMELEN
], line
[MAXHOSTNAMELEN
];
1151 static int first
= 1;
1155 if (first
&& !nflag
) {
1157 if (gethostname(domain
, sizeof domain
) == 0 &&
1158 (cp
= strchr(domain
, '.')) != NULL
) {
1159 strlcpy(domain
, cp
+ 1, sizeof(domain
));
1162 if (!nflag
&& in
.s_addr
!= INADDR_ANY
) {
1163 hp
= gethostbyaddr((char *)&in
, sizeof(in
), AF_INET
);
1165 if ((cp
= strchr(hp
->h_name
, '.')) != NULL
&&
1166 strcmp(cp
+ 1, domain
) == 0)
1168 strlcpy(line
, hp
->h_name
, sizeof(line
));
1172 return (inet_ntoa(in
));
1179 "usage: %s [-cdDIlMnrSv] [-f first_ttl] [-g gateway_addr] [-m max_ttl]\n"
1180 "\t[-p port] [-P proto] [-q nqueries] [-s src_addr] [-t tos]\n"
1181 "\t[-w waittime] host [packetsize]\n", getprogname());