1 /* vi: set sw=4 ts=4: */
3 * Copyright (c) 1988, 1989, 1991, 1994, 1995, 1996, 1997, 1998, 1999, 2000
4 * The Regents of the University of California. All rights reserved.
6 * Busybox port by Vladimir Oleynik (C) 2005 <dzo@simtreas.ru>
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that: (1) source code distributions
10 * retain the above copyright notice and this paragraph in its entirety, (2)
11 * distributions including binary code include the above copyright notice and
12 * this paragraph in its entirety in the documentation or other materials
13 * provided with the distribution, and (3) all advertising materials mentioning
14 * features or use of this software display the following acknowledgement:
15 * ``This product includes software developed by the University of California,
16 * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
17 * the University nor the names of its contributors may be used to endorse
18 * or promote products derived from this software without specific prior
20 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
21 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
22 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
28 * Modified for NRL 4.4BSD IPv6 release.
31 * Modified for Linux IPv6 by Pedro Roque <roque@di.fc.ul.pt>
34 * As ICMP error messages for IPv6 now include more than 8 bytes
35 * UDP datagrams are now sent via an UDP socket instead of magic
38 * Converted to busybox applet by Leonid Lisovskiy <lly@sf.net>
43 * traceroute host - trace the route ip packets follow going to "host".
45 * Attempt to trace the route an ip packet would follow to some
46 * internet host. We find out intermediate hops by launching probe
47 * packets with a small ttl (time to live) then listening for an
48 * icmp "time exceeded" reply from a gateway. We start our probes
49 * with a ttl of one and increase by one until we get an icmp "port
50 * unreachable" (which means we got to "host") or hit a max (which
51 * defaults to 30 hops & can be changed with the -m flag). Three
52 * probes (change with -q flag) are sent at each ttl setting and a
53 * line is printed showing the ttl, address of the gateway and
54 * round trip time of each probe. If the probe answers come from
55 * different gateways, the address of each responding system will
56 * be printed. If there is no response within a 5 sec. timeout
57 * interval (changed with the -w flag), a "*" is printed for that
60 * Probe packets are UDP format. We don't want the destination
61 * host to process them so the destination port is set to an
62 * unlikely value (if some clod on the destination is using that
63 * value, it can be changed with the -p flag).
65 * A sample use might be:
67 * [yak 71]% traceroute nis.nsf.net.
68 * traceroute to nis.nsf.net (35.1.1.48), 30 hops max, 56 byte packet
69 * 1 helios.ee.lbl.gov (128.3.112.1) 19 ms 19 ms 0 ms
70 * 2 lilac-dmc.Berkeley.EDU (128.32.216.1) 39 ms 39 ms 19 ms
71 * 3 lilac-dmc.Berkeley.EDU (128.32.216.1) 39 ms 39 ms 19 ms
72 * 4 ccngw-ner-cc.Berkeley.EDU (128.32.136.23) 39 ms 40 ms 39 ms
73 * 5 ccn-nerif22.Berkeley.EDU (128.32.168.22) 39 ms 39 ms 39 ms
74 * 6 128.32.197.4 (128.32.197.4) 40 ms 59 ms 59 ms
75 * 7 131.119.2.5 (131.119.2.5) 59 ms 59 ms 59 ms
76 * 8 129.140.70.13 (129.140.70.13) 99 ms 99 ms 80 ms
77 * 9 129.140.71.6 (129.140.71.6) 139 ms 239 ms 319 ms
78 * 10 129.140.81.7 (129.140.81.7) 220 ms 199 ms 199 ms
79 * 11 nic.merit.edu (35.1.1.48) 239 ms 239 ms 239 ms
81 * Note that lines 2 & 3 are the same. This is due to a buggy
82 * kernel on the 2nd hop system -- lbl-csam.arpa -- that forwards
83 * packets with a zero ttl.
85 * A more interesting example is:
87 * [yak 72]% traceroute allspice.lcs.mit.edu.
88 * traceroute to allspice.lcs.mit.edu (18.26.0.115), 30 hops max
89 * 1 helios.ee.lbl.gov (128.3.112.1) 0 ms 0 ms 0 ms
90 * 2 lilac-dmc.Berkeley.EDU (128.32.216.1) 19 ms 19 ms 19 ms
91 * 3 lilac-dmc.Berkeley.EDU (128.32.216.1) 39 ms 19 ms 19 ms
92 * 4 ccngw-ner-cc.Berkeley.EDU (128.32.136.23) 19 ms 39 ms 39 ms
93 * 5 ccn-nerif22.Berkeley.EDU (128.32.168.22) 20 ms 39 ms 39 ms
94 * 6 128.32.197.4 (128.32.197.4) 59 ms 119 ms 39 ms
95 * 7 131.119.2.5 (131.119.2.5) 59 ms 59 ms 39 ms
96 * 8 129.140.70.13 (129.140.70.13) 80 ms 79 ms 99 ms
97 * 9 129.140.71.6 (129.140.71.6) 139 ms 139 ms 159 ms
98 * 10 129.140.81.7 (129.140.81.7) 199 ms 180 ms 300 ms
99 * 11 129.140.72.17 (129.140.72.17) 300 ms 239 ms 239 ms
101 * 13 128.121.54.72 (128.121.54.72) 259 ms 499 ms 279 ms
106 * 18 ALLSPICE.LCS.MIT.EDU (18.26.0.115) 339 ms 279 ms 279 ms
108 * (I start to see why I'm having so much trouble with mail to
109 * MIT.) Note that the gateways 12, 14, 15, 16 & 17 hops away
110 * either don't send ICMP "time exceeded" messages or send them
111 * with a ttl too small to reach us. 14 - 17 are running the
112 * MIT C Gateway code that doesn't send "time exceeded"s. God
113 * only knows what's going on with 12.
115 * The silent gateway 12 in the above may be the result of a bug in
116 * the 4.[23]BSD network code (and its derivatives): 4.x (x <= 3)
117 * sends an unreachable message using whatever ttl remains in the
118 * original datagram. Since, for gateways, the remaining ttl is
119 * zero, the icmp "time exceeded" is guaranteed to not make it back
120 * to us. The behavior of this bug is slightly more interesting
121 * when it appears on the destination system:
123 * 1 helios.ee.lbl.gov (128.3.112.1) 0 ms 0 ms 0 ms
124 * 2 lilac-dmc.Berkeley.EDU (128.32.216.1) 39 ms 19 ms 39 ms
125 * 3 lilac-dmc.Berkeley.EDU (128.32.216.1) 19 ms 39 ms 19 ms
126 * 4 ccngw-ner-cc.Berkeley.EDU (128.32.136.23) 39 ms 40 ms 19 ms
127 * 5 ccn-nerif35.Berkeley.EDU (128.32.168.35) 39 ms 39 ms 39 ms
128 * 6 csgw.Berkeley.EDU (128.32.133.254) 39 ms 59 ms 39 ms
135 * 13 rip.Berkeley.EDU (128.32.131.22) 59 ms ! 39 ms ! 39 ms !
137 * Notice that there are 12 "gateways" (13 is the final
138 * destination) and exactly the last half of them are "missing".
139 * What's really happening is that rip (a Sun-3 running Sun OS3.5)
140 * is using the ttl from our arriving datagram as the ttl in its
141 * icmp reply. So, the reply will time out on the return path
142 * (with no notice sent to anyone since icmp's aren't sent for
143 * icmp's) until we probe with a ttl that's at least twice the path
144 * length. I.e., rip is really only 7 hops away. A reply that
145 * returns with a ttl of 1 is a clue this problem exists.
146 * Traceroute prints a "!" after the time if the ttl is <= 1.
147 * Since vendors ship a lot of obsolete (DEC's Ultrix, Sun 3.x) or
148 * non-standard (HPUX) software, expect to see this problem
149 * frequently and/or take care picking the target host of your
152 * Other possible annotations after the time are !H, !N, !P (got a host,
153 * network or protocol unreachable, respectively), !S or !F (source
154 * route failed or fragmentation needed -- neither of these should
155 * ever occur and the associated gateway is busted if you see one). If
156 * almost all the probes result in some kind of unreachable, traceroute
157 * will give up and exit.
161 * This program must be run by root or be setuid. (I suggest that
162 * you *don't* make it setuid -- casual use could result in a lot
163 * of unnecessary traffic on our poor, congested nets.)
165 * This program requires a kernel mod that does not appear in any
166 * system available from Berkeley: A raw ip socket using proto
167 * IPPROTO_RAW must interpret the data sent as an ip datagram (as
168 * opposed to data to be wrapped in a ip datagram). See the README
169 * file that came with the source to this program for a description
170 * of the mods I made to /sys/netinet/raw_ip.c. Your mileage may
171 * vary. But, again, ANY 4.x (x < 4) BSD KERNEL WILL HAVE TO BE
172 * MODIFIED TO RUN THIS PROGRAM.
174 * The udp port usage may appear bizarre (well, ok, it is bizarre).
175 * The problem is that an icmp message only contains 8 bytes of
176 * data from the original datagram. 8 bytes is the size of a udp
177 * header so, if we want to associate replies with the original
178 * datagram, the necessary information must be encoded into the
179 * udp header (the ip id could be used but there's no way to
180 * interlock with the kernel's assignment of ip id's and, anyway,
181 * it would have taken a lot more kernel hacking to allow this
182 * code to set the ip id). So, to allow two or more users to
183 * use traceroute simultaneously, we use this task's pid as the
184 * source port (the high bit is set to move the port number out
185 * of the "likely" range). To keep track of which probe is being
186 * replied to (so times and/or hop counts don't get confused by a
187 * reply that was delayed in transit), we increment the destination
188 * port number before each probe.
190 * Don't use this as a coding example. I was trying to find a
191 * routing problem and this code sort-of popped out after 48 hours
192 * without sleep. I was amazed it ever compiled, much less ran.
194 * I stole the idea for this program from Steve Deering. Since
195 * the first release, I've learned that had I attended the right
196 * IETF working group meetings, I also could have stolen it from Guy
197 * Almes or Matt Mathis. I don't know (or care) who came up with
198 * the idea first. I envy the originators' perspicacity and I'm
199 * glad they didn't keep the idea a secret.
201 * Tim Seaver, Ken Adelman and C. Philip Wood provided bug fixes and/or
202 * enhancements to the original distribution.
204 * I've hacked up a round-trip-route version of this that works by
205 * sending a loose-source-routed udp datagram through the destination
206 * back to yourself. Unfortunately, SO many gateways botch source
207 * routing, the thing is almost worthless. Maybe one day...
209 * -- Van Jacobson (van@ee.lbl.gov)
210 * Tue Dec 20 03:50:13 PST 1988
213 //usage:#define traceroute_trivial_usage
214 //usage: "[-"IF_TRACEROUTE6("46")"FIlnrv] [-f 1ST_TTL] [-m MAXTTL] [-q PROBES] [-p PORT]\n"
215 //usage: " [-t TOS] [-w WAIT_SEC] [-s SRC_IP] [-i IFACE]\n"
216 //usage: " [-z PAUSE_MSEC] HOST [BYTES]"
217 //usage:#define traceroute_full_usage "\n\n"
218 //usage: "Trace the route to HOST\n"
219 //usage: IF_TRACEROUTE6(
220 //usage: "\n -4,-6 Force IP or IPv6 name resolution"
222 //usage: "\n -F Set don't fragment bit"
223 //usage: IF_FEATURE_TRACEROUTE_USE_ICMP(
224 //usage: "\n -I Use ICMP ECHO instead of UDP datagrams"
226 //usage: "\n -l Display TTL value of the returned packet"
227 //Currently disabled (TRACEROUTE_SO_DEBUG==0)
228 ////usage: "\n -d Set SO_DEBUG options to socket"
229 //usage: "\n -n Print numeric addresses"
230 //usage: "\n -r Bypass routing tables, send directly to HOST"
231 //usage: IF_FEATURE_TRACEROUTE_VERBOSE(
232 //usage: "\n -v Verbose"
234 //usage: "\n -f N First number of hops (default 1)"
235 //usage: "\n -m N Max number of hops"
236 //usage: "\n -q N Number of probes per hop (default 3)"
237 //usage: "\n -p N Base UDP port number used in probes"
238 //usage: "\n (default 33434)"
239 //usage: "\n -s IP Source address"
240 //usage: "\n -i IFACE Source interface"
241 //usage: "\n -t N Type-of-service in probe packets (default 0)"
242 //usage: "\n -w SEC Time to wait for a response (default 3)"
243 //usage: "\n -g IP Loose source route gateway (8 max)"
245 //usage:#define traceroute6_trivial_usage
246 //usage: "[-nrv] [-m MAXTTL] [-q PROBES] [-p PORT]\n"
247 //usage: " [-t TOS] [-w WAIT_SEC] [-s SRC_IP] [-i IFACE]\n"
248 //usage: " HOST [BYTES]"
249 //usage:#define traceroute6_full_usage "\n\n"
250 //usage: "Trace the route to HOST\n"
251 //Currently disabled (TRACEROUTE_SO_DEBUG==0)
252 ////usage: "\n -d Set SO_DEBUG options to socket"
253 //usage: "\n -n Print numeric addresses"
254 //usage: "\n -r Bypass routing tables, send directly to HOST"
255 //usage: IF_FEATURE_TRACEROUTE_VERBOSE(
256 //usage: "\n -v Verbose"
258 //usage: "\n -m N Max number of hops"
259 //usage: "\n -q N Number of probes per hop (default 3)"
260 //usage: "\n -p N Base UDP port number used in probes"
261 //usage: "\n (default 33434)"
262 //usage: "\n -s IP Source address"
263 //usage: "\n -i IFACE Source interface"
264 //usage: "\n -t N Type-of-service in probe packets (default 0)"
265 //usage: "\n -w SEC Time wait for a response (default 3)"
267 #define TRACEROUTE_SO_DEBUG 0
270 #include <arpa/inet.h>
271 #include <netinet/in.h>
272 #include <netinet/udp.h>
273 #include <netinet/ip.h>
274 #include <netinet/ip_icmp.h>
275 #if ENABLE_FEATURE_IPV6
276 # include <netinet/ip6.h>
277 # include <netinet/icmp6.h>
279 # define SOL_IPV6 IPPROTO_IPV6
284 #include "inet_common.h"
287 # define IPPROTO_ICMP 1
290 # define IPPROTO_IP 0
295 "FIlnrdvxt:i:m:p:q:s:w:z:f:" \
296 "4" IF_TRACEROUTE6("6")
298 OPT_DONT_FRAGMNT = (1 << 0), /* F */
299 OPT_USE_ICMP = (1 << 1) * ENABLE_FEATURE_TRACEROUTE_USE_ICMP, /* I */
300 OPT_TTL_FLAG = (1 << 2), /* l */
301 OPT_ADDR_NUM = (1 << 3), /* n */
302 OPT_BYPASS_ROUTE = (1 << 4), /* r */
303 OPT_DEBUG = (1 << 5), /* d */
304 OPT_VERBOSE = (1 << 6) * ENABLE_FEATURE_TRACEROUTE_VERBOSE, /* v */
305 OPT_IP_CHKSUM = (1 << 7), /* x */
306 OPT_TOS = (1 << 8), /* t */
307 OPT_DEVICE = (1 << 9), /* i */
308 OPT_MAX_TTL = (1 << 10), /* m */
309 OPT_PORT = (1 << 11), /* p */
310 OPT_NPROBES = (1 << 12), /* q */
311 OPT_SOURCE = (1 << 13), /* s */
312 OPT_WAITTIME = (1 << 14), /* w */
313 OPT_PAUSE_MS = (1 << 15), /* z */
314 OPT_FIRST_TTL = (1 << 16), /* f */
315 OPT_IPV4 = (1 << 17), /* 4 */
316 OPT_IPV6 = (1 << 18) * ENABLE_TRACEROUTE6, /* 6 */
318 #define verbose (option_mask32 & OPT_VERBOSE)
322 rcvsock = 3, /* receive (icmp) socket file descriptor */
323 sndsock = 4, /* send (udp/icmp) socket file descriptor */
326 /* Data section of the probe packet */
328 unsigned char seq; /* sequence number of this packet */
329 unsigned char ttl; /* ttl packet left with */
330 // UNUSED. Retaining to have the same packet size.
331 struct timeval tv_UNUSED PACKED; /* time packet left */
334 #if ENABLE_TRACEROUTE6
338 struct timeval tv_UNUSED PACKED; /* time packet left */
343 /* Pointer to entire malloced IP packet, "packlen" bytes long: */
345 /* Pointer to ICMP or UDP payload (not header): */
346 struct outdata_t *outdata;
348 len_and_sockaddr *dest_lsa;
349 int packlen; /* total length of packet */
350 int pmtu; /* Path MTU Discovery (RFC1191) */
352 uint16_t port; // 33434; /* start udp dest port # for probe packets */
353 int waittime; // 5; /* time to wait for response (in seconds) */
354 unsigned char recv_pkt[512]; /* last inbound (icmp) packet */
357 #define G (*ptr_to_globals)
358 #define outip (G.outip )
359 #define outdata (G.outdata )
360 #define dest_lsa (G.dest_lsa )
361 #define packlen (G.packlen )
362 #define pmtu (G.pmtu )
363 #define ident (G.ident )
364 #define port (G.port )
365 #define waittime (G.waittime )
366 #define recv_pkt (G.recv_pkt )
367 #define gwlist (G.gwlist )
368 #define INIT_G() do { \
369 SET_PTR_TO_GLOBALS(xzalloc(sizeof(G))); \
374 #define outicmp ((struct icmp *)(outip + 1))
375 #define outudp ((struct udphdr *)(outip + 1))
379 wait_for_reply(len_and_sockaddr *from_lsa, struct sockaddr *to, unsigned *timestamp_us, int *left_ms)
381 struct pollfd pfd[1];
385 pfd[0].events = POLLIN;
386 if (*left_ms >= 0 && safe_poll(pfd, 1, *left_ms) > 0) {
389 read_len = recv_from_to(rcvsock,
390 recv_pkt, sizeof(recv_pkt),
391 /*flags:*/ MSG_DONTWAIT,
392 &from_lsa->u.sa, to, from_lsa->len);
394 *left_ms -= (t - *timestamp_us) / 1000;
402 send_probe(int seq, int ttl)
408 #if ENABLE_TRACEROUTE6
409 if (dest_lsa->u.sa.sa_family == AF_INET6) {
410 struct outdata6_t *pkt = (struct outdata6_t *) outdata;
411 pkt->ident6 = htonl(ident);
412 pkt->seq6 = htonl(seq);
413 /*gettimeofday(&pkt->tv, &tz);*/
419 // UNUSED: was storing gettimeofday's result there, but never ever checked it
420 /*memcpy(&outdata->tv, tp, sizeof(outdata->tv));*/
422 if (option_mask32 & OPT_USE_ICMP) {
423 outicmp->icmp_seq = htons(seq);
425 /* Always calculate checksum for icmp packets */
426 outicmp->icmp_cksum = 0;
427 outicmp->icmp_cksum = inet_cksum(
429 ((char*)outip + packlen) - (char*)outicmp
431 if (outicmp->icmp_cksum == 0)
432 outicmp->icmp_cksum = 0xffff;
436 //BUG! verbose is (x & OPT_VERBOSE), not a counter!
437 #if 0 //ENABLE_FEATURE_TRACEROUTE_VERBOSE
438 /* XXX undocumented debugging hack */
443 sp = (uint16_t *)outip;
444 nshorts = (unsigned)packlen / sizeof(uint16_t);
446 printf("[ %d bytes", packlen);
447 while (--nshorts >= 0) {
450 printf(" %04x", ntohs(*sp));
456 printf(" %02x", *(unsigned char *)sp);
463 #if ENABLE_TRACEROUTE6
464 if (dest_lsa->u.sa.sa_family == AF_INET6) {
465 res = setsockopt_int(sndsock, SOL_IPV6, IPV6_UNICAST_HOPS, ttl);
467 bb_perror_msg_and_die("setsockopt(%s) %d", "UNICAST_HOPS", ttl);
472 res = setsockopt_int(sndsock, IPPROTO_IP, IP_TTL, ttl);
474 bb_perror_msg_and_die("setsockopt(%s) %d", "TTL", ttl);
476 if (option_mask32 & OPT_USE_ICMP)
480 if (!(option_mask32 & OPT_USE_ICMP)) {
481 set_nport(&dest_lsa->u.sa, htons(port + seq));
483 len = ((char*)outip + packlen) - (char*)out;
484 res = xsendto(sndsock, out, len, &dest_lsa->u.sa, dest_lsa->len);
486 bb_error_msg("sent %d octets, ret=%d", len, res);
489 #if ENABLE_FEATURE_TRACEROUTE_VERBOSE
491 * Convert an ICMP "type" field to a printable string.
494 pr_type(unsigned char t)
496 static const char *const ttab[] = {
497 "Echo Reply", "ICMP 1", "ICMP 2", "Dest Unreachable",
498 "Source Quench", "Redirect", "ICMP 6", "ICMP 7",
499 "Echo", "Router Advert", "Router Solicit", "Time Exceeded",
500 "Param Problem", "Timestamp", "Timestamp Reply", "Info Request",
501 "Info Reply", "Mask Request", "Mask Reply"
503 # if ENABLE_TRACEROUTE6
504 static const char *const ttab6[] = {
505 [0] "Error", "Dest Unreachable", "Packet Too Big", "Time Exceeded",
507 [8] "Echo Request", "Echo Reply", "Membership Query", "Membership Report",
508 [12] "Membership Reduction", "Router Solicit", "Router Advert", "Neighbor Solicit",
509 [16] "Neighbor Advert", "Redirect",
512 if (dest_lsa->u.sa.sa_family == AF_INET6) {
515 if (t < 128 || t > ND_REDIRECT)
516 return "OUT-OF-RANGE";
517 return ttab6[(t & 63) + 8];
520 if (t >= ARRAY_SIZE(ttab))
521 return "OUT-OF-RANGE";
527 #if !ENABLE_FEATURE_TRACEROUTE_VERBOSE
528 #define packet4_ok(read_len, from, seq) \
529 packet4_ok(read_len, seq)
532 packet4_ok(int read_len, const struct sockaddr_in *from, int seq)
534 const struct icmp *icp;
535 unsigned char type, code;
539 ip = (struct ip *) recv_pkt;
540 hlen = ip->ip_hl << 2;
541 if (read_len < hlen + ICMP_MINLEN) {
542 #if ENABLE_FEATURE_TRACEROUTE_VERBOSE
544 printf("packet too short (%d bytes) from %s\n", read_len,
545 inet_ntoa(from->sin_addr));
550 icp = (struct icmp *)(recv_pkt + hlen);
551 type = icp->icmp_type;
552 code = icp->icmp_code;
553 /* Path MTU Discovery (RFC1191) */
555 if (code == ICMP_UNREACH_NEEDFRAG)
556 pmtu = ntohs(icp->icmp_nextmtu);
558 if ((type == ICMP_TIMXCEED && code == ICMP_TIMXCEED_INTRANS)
559 || type == ICMP_UNREACH
560 || type == ICMP_ECHOREPLY
562 const struct ip *hip;
563 const struct udphdr *up;
566 hlen = hip->ip_hl << 2;
567 if (option_mask32 & OPT_USE_ICMP) {
571 if (type == ICMP_ECHOREPLY
572 && icp->icmp_id == htons(ident)
573 && icp->icmp_seq == htons(seq)
575 return ICMP_UNREACH_PORT+1;
578 hicmp = (struct icmp *)((unsigned char *)hip + hlen);
579 if (hlen + SIZEOF_ICMP_HDR <= read_len
580 && hip->ip_p == IPPROTO_ICMP
581 && hicmp->icmp_id == htons(ident)
582 && hicmp->icmp_seq == htons(seq)
584 return (type == ICMP_TIMXCEED ? -1 : code + 1);
587 up = (struct udphdr *)((char *)hip + hlen);
588 if (hlen + 12 <= read_len
589 && hip->ip_p == IPPROTO_UDP
590 // Off: since we do not form the entire IP packet,
591 // but defer it to kernel, we can't set source port,
592 // and thus can't check it here in the reply
593 /* && up->source == htons(ident) */
594 && up->dest == htons(port + seq)
596 return (type == ICMP_TIMXCEED ? -1 : code + 1);
600 #if ENABLE_FEATURE_TRACEROUTE_VERBOSE
603 uint32_t *lp = (uint32_t *)&icp->icmp_ip;
605 printf("\n%d bytes from %s to "
606 "%s: icmp type %d (%s) code %d\n",
607 read_len, inet_ntoa(from->sin_addr),
608 inet_ntoa(ip->ip_dst),
609 type, pr_type(type), icp->icmp_code);
610 for (i = 4; i < read_len; i += sizeof(*lp))
611 printf("%2d: x%8.8x\n", i, *lp++);
617 #if ENABLE_TRACEROUTE6
618 # if !ENABLE_FEATURE_TRACEROUTE_VERBOSE
619 #define packet_ok(read_len, from_lsa, to, seq) \
620 packet_ok(read_len, from_lsa, seq)
623 packet_ok(int read_len, len_and_sockaddr *from_lsa,
627 const struct icmp6_hdr *icp;
628 unsigned char type, code;
630 if (from_lsa->u.sa.sa_family == AF_INET)
631 return packet4_ok(read_len, &from_lsa->u.sin, seq);
633 icp = (struct icmp6_hdr *) recv_pkt;
635 type = icp->icmp6_type;
636 code = icp->icmp6_code;
638 if ((type == ICMP6_TIME_EXCEEDED && code == ICMP6_TIME_EXCEED_TRANSIT)
639 || type == ICMP6_DST_UNREACH
645 hip = (struct ip6_hdr *)(icp + 1);
646 up = (struct udphdr *) (hip + 1);
647 nexthdr = hip->ip6_nxt;
649 if (nexthdr == IPPROTO_FRAGMENT) {
650 nexthdr = *(unsigned char*)up;
653 if (nexthdr == IPPROTO_UDP) {
654 struct outdata6_t *pkt;
656 pkt = (struct outdata6_t *) (up + 1);
658 if (ntohl(pkt->ident6) == ident
659 && ntohl(pkt->seq6) == seq
661 return (type == ICMP6_TIME_EXCEEDED ? -1 : (code<<8)+1);
666 # if ENABLE_FEATURE_TRACEROUTE_VERBOSE
669 char pa1[MAXHOSTNAMELEN];
670 char pa2[MAXHOSTNAMELEN];
673 p = (unsigned char *) (icp + 1);
675 printf("\n%d bytes from %s to "
676 "%s: icmp type %d (%s) code %d\n",
678 inet_ntop(AF_INET6, &from_lsa->u.sin6.sin6_addr, pa1, sizeof(pa1)),
679 inet_ntop(AF_INET6, &((struct sockaddr_in6*)to)->sin6_addr, pa2, sizeof(pa2)),
680 type, pr_type(type), icp->icmp6_code);
682 read_len -= sizeof(struct icmp6_hdr);
683 for (i = 0; i < read_len; i++) {
688 printf("%02x", p[i]);
689 if ((i % 16 == 15) && (i + 1 < read_len))
698 #else /* !ENABLE_TRACEROUTE6 */
699 static ALWAYS_INLINE int
700 packet_ok(int read_len,
701 len_and_sockaddr *from_lsa IF_NOT_FEATURE_TRACEROUTE_VERBOSE(UNUSED_PARAM),
702 struct sockaddr *to UNUSED_PARAM,
705 return packet4_ok(read_len, &from_lsa->u.sin, seq);
710 * Construct an Internet address representation.
711 * If the -n flag has been supplied, give
712 * numeric value, otherwise try for symbolic name.
715 print_inetname(const struct sockaddr *from)
717 char *ina = xmalloc_sockaddr2dotted_noport(from);
719 if (option_mask32 & OPT_ADDR_NUM) {
724 if (from->sa_family != AF_INET
725 || ((struct sockaddr_in*)from)->sin_addr.s_addr != INADDR_ANY
727 /* Try to reverse resolve if it is not 0.0.0.0 */
728 n = xmalloc_sockaddr2host_noport((struct sockaddr*)from);
730 printf(" %s (%s)", (n ? n : ina), ina);
737 print(int read_len, const struct sockaddr *from, const struct sockaddr *to)
739 print_inetname(from);
742 char *ina = xmalloc_sockaddr2dotted_noport(to);
743 #if ENABLE_TRACEROUTE6
744 if (to->sa_family == AF_INET6) {
745 read_len -= sizeof(struct ip6_hdr);
749 struct ip *ip4packet = (struct ip*)recv_pkt;
750 read_len -= ip4packet->ip_hl << 2;
752 printf(" %d bytes to %s", read_len, ina);
758 print_delta_ms(unsigned t1p, unsigned t2p)
760 unsigned tt = t2p - t1p;
761 printf(" %u.%03u ms", tt / 1000, tt % 1000);
765 * Usage: [-dFIlnrvx] [-g gateway] [-i iface] [-f first_ttl]
766 * [-m max_ttl] [ -p port] [-q nqueries] [-s src_addr] [-t tos]
767 * [-w waittime] [-z pausemsecs] host [packetlen]"
770 common_traceroute_main(int op, char **argv)
779 unsigned pausemsecs = 0;
787 char *pausemsecs_str;
790 #if ENABLE_TRACEROUTE6
793 enum { af = AF_INET };
797 len_and_sockaddr *from_lsa;
798 struct sockaddr *lastaddr;
804 opt_complementary = "-1:x-x";
805 op |= getopt32(argv, OPT_STRING
806 , &tos_str, &device, &max_ttl_str, &port_str, &nprobes_str
807 , &source, &waittime_str, &pausemsecs_str, &first_ttl_str
812 if (op & OPT_IP_CHKSUM)
813 bb_error_msg("warning: ip checksums disabled");
817 tos = xatou_range(tos_str, 0, 255);
819 if (op & OPT_MAX_TTL)
820 max_ttl = xatou_range(max_ttl_str, 1, 255);
822 port = xatou16(port_str);
823 if (op & OPT_NPROBES)
824 nprobes = xatou_range(nprobes_str, 1, INT_MAX);
825 if (op & OPT_SOURCE) {
827 * set the ip source address of the outbound
828 * probe (e.g., on a multi-homed host).
831 bb_error_msg_and_die(bb_msg_you_must_be_root);
833 if (op & OPT_WAITTIME)
834 waittime = xatou_range(waittime_str, 1, 24 * 60 * 60);
835 if (op & OPT_PAUSE_MS)
836 pausemsecs = xatou_range(pausemsecs_str, 0, 60 * 60 * 1000);
837 if (op & OPT_FIRST_TTL)
838 first_ttl = xatou_range(first_ttl_str, 1, max_ttl);
840 /* Process destination and optional packet size */
841 minpacket = sizeof(struct ip)
843 + sizeof(struct outdata_t);
844 if (!(op & OPT_USE_ICMP))
845 minpacket = sizeof(struct ip)
846 + sizeof(struct udphdr)
847 + sizeof(struct outdata_t);
848 #if ENABLE_TRACEROUTE6
854 dest_lsa = xhost_and_af2sockaddr(argv[0], port, af);
855 af = dest_lsa->u.sa.sa_family;
857 minpacket = sizeof(struct ip6_hdr)
858 + sizeof(struct udphdr)
859 + sizeof(struct outdata6_t);
861 dest_lsa = xhost2sockaddr(argv[0], port);
865 packlen = xatoul_range(argv[1], minpacket, 32 * 1024);
867 /* Ensure the socket fds won't be 0, 1 or 2 */
870 #if ENABLE_TRACEROUTE6
871 if (af == AF_INET6) {
872 xmove_fd(xsocket(AF_INET6, SOCK_RAW, IPPROTO_ICMPV6), rcvsock);
873 # ifdef IPV6_RECVPKTINFO
874 setsockopt_1(rcvsock, SOL_IPV6, IPV6_RECVPKTINFO);
875 setsockopt_1(rcvsock, SOL_IPV6, IPV6_2292PKTINFO);
877 setsockopt_1(rcvsock, SOL_IPV6, IPV6_PKTINFO);
882 xmove_fd(xsocket(AF_INET, SOCK_RAW, IPPROTO_ICMP), rcvsock);
885 #if TRACEROUTE_SO_DEBUG
887 setsockopt_SOL_SOCKET_1(rcvsock, SO_DEBUG);
889 if (op & OPT_BYPASS_ROUTE)
890 setsockopt_SOL_SOCKET_1(rcvsock, SO_DONTROUTE);
892 #if ENABLE_TRACEROUTE6
893 if (af == AF_INET6) {
894 if (setsockopt_int(rcvsock, SOL_RAW, IPV6_CHECKSUM, 2) != 0)
895 bb_perror_msg_and_die("setsockopt(%s)", "IPV6_CHECKSUM");
896 xmove_fd(xsocket(af, SOCK_DGRAM, 0), sndsock);
900 if (op & OPT_USE_ICMP)
901 xmove_fd(xsocket(AF_INET, SOCK_RAW, IPPROTO_ICMP), sndsock);
903 xmove_fd(xsocket(AF_INET, SOCK_DGRAM, 0), sndsock);
907 if (setsockopt_SOL_SOCKET_int(sndsock, SO_SNDBUF, packlen) != 0) {
908 bb_perror_msg_and_die("setsockopt(%s)", "SO_SNDBUF");
912 if ((op & OPT_TOS) && setsockopt_int(sndsock, IPPROTO_IP, IP_TOS, tos) != 0) {
913 bb_perror_msg_and_die("setsockopt(%s) %d", "TOS", tos);
917 if (op & OPT_DONT_FRAGMNT)
918 setsockopt_1(sndsock, IPPROTO_IP, IP_DONTFRAG);
920 #if TRACEROUTE_SO_DEBUG
922 setsockopt_SOL_SOCKET_1(sndsock, SO_DEBUG);
924 if (op & OPT_BYPASS_ROUTE)
925 setsockopt_SOL_SOCKET_1(sndsock, SO_DONTROUTE);
927 outip = xzalloc(packlen);
931 if (!ENABLE_TRACEROUTE6 || af == AF_INET) {
932 if (op & OPT_USE_ICMP) {
934 outicmp->icmp_type = ICMP_ECHO;
935 outicmp->icmp_id = htons(ident);
936 outdata = (struct outdata_t *)((char *)outicmp + SIZEOF_ICMP_HDR);
938 outdata = (struct outdata_t *)(outudp + 1);
941 #if ENABLE_TRACEROUTE6
942 if (af == AF_INET6) {
943 outdata = (void*)((char*)outip
944 + sizeof(struct ip6_hdr)
945 + sizeof(struct udphdr)
950 if (op & OPT_DEVICE) /* hmm, do we need error check? */
951 setsockopt_bindtodevice(sndsock, device);
953 if (op & OPT_SOURCE) {
954 #if ENABLE_TRACEROUTE6
955 // TODO: need xdotted_and_af2sockaddr?
956 len_and_sockaddr *source_lsa = xhost_and_af2sockaddr(source, 0, af);
958 len_and_sockaddr *source_lsa = xdotted2sockaddr(source, 0);
960 /* Ping4 does this (why?) */
962 if (setsockopt(sndsock, IPPROTO_IP, IP_MULTICAST_IF,
963 &source_lsa->u.sa, source_lsa->len))
964 bb_error_msg_and_die("can't set multicast source interface");
965 //TODO: we can query source port we bound to,
966 // and check it in replies... if we care enough
967 xbind(sndsock, &source_lsa->u.sa, source_lsa->len);
970 #if ENABLE_TRACEROUTE6
971 else if (af == AF_INET6) {
972 //TODO: why we don't do it for IPv4?
973 len_and_sockaddr *source_lsa;
975 int probe_fd = xsocket(af, SOCK_DGRAM, 0);
977 setsockopt_bindtodevice(probe_fd, device);
978 set_nport(&dest_lsa->u.sa, htons(1025));
979 /* dummy connect. makes kernel pick source IP (and port) */
980 xconnect(probe_fd, &dest_lsa->u.sa, dest_lsa->len);
981 set_nport(&dest_lsa->u.sa, htons(port));
983 /* read IP and port */
984 source_lsa = get_sock_lsa(probe_fd);
985 if (source_lsa == NULL)
986 bb_error_msg_and_die("can't get probe addr");
990 /* bind our sockets to this IP (but not port) */
991 set_nport(&source_lsa->u.sa, 0);
992 xbind(sndsock, &source_lsa->u.sa, source_lsa->len);
993 xbind(rcvsock, &source_lsa->u.sa, source_lsa->len);
999 /* Revert to non-privileged user after opening sockets */
1003 dest_str = xmalloc_sockaddr2dotted_noport(&dest_lsa->u.sa);
1004 printf("traceroute to %s (%s)", argv[0], dest_str);
1005 if (ENABLE_FEATURE_CLEAN_UP) {
1009 if (op & OPT_SOURCE)
1010 printf(" from %s", source);
1011 printf(", %d hops max, %d byte packets\n", max_ttl, packlen);
1013 from_lsa = xmemdup(dest_lsa, LSA_LEN_SIZE + dest_lsa->len);
1014 lastaddr = xzalloc(dest_lsa->len);
1015 to = xzalloc(dest_lsa->len);
1017 for (ttl = first_ttl; ttl <= max_ttl; ++ttl) {
1019 int unreachable = 0; /* counter */
1020 int gotlastaddr = 0; /* flags */
1024 for (probe = 0; probe < nprobes; ++probe) {
1032 if (probe != 0 && pausemsecs > 0)
1033 usleep(pausemsecs * 1000);
1035 send_probe(++seq, ttl);
1036 t2 = t1 = monotonic_us();
1038 left_ms = waittime * 1000;
1039 while ((read_len = wait_for_reply(from_lsa, to, &t2, &left_ms)) != 0) {
1042 /* Recv'ed a packet, or read error */
1043 /* t2 = monotonic_us() - set by wait_for_reply */
1047 icmp_code = packet_ok(read_len, from_lsa, to, seq);
1048 /* Skip short packet */
1053 || (memcmp(lastaddr, &from_lsa->u.sa, from_lsa->len) != 0)
1055 print(read_len, &from_lsa->u.sa, to);
1056 memcpy(lastaddr, &from_lsa->u.sa, from_lsa->len);
1060 print_delta_ms(t1, t2);
1061 ip = (struct ip *)recv_pkt;
1063 if (from_lsa->u.sa.sa_family == AF_INET)
1064 if (op & OPT_TTL_FLAG)
1065 printf(" (%d)", ip->ip_ttl);
1067 /* time exceeded in transit */
1068 if (icmp_code == -1)
1071 switch (icmp_code) {
1072 #if ENABLE_TRACEROUTE6
1073 case ICMP6_DST_UNREACH_NOPORT << 8:
1077 case ICMP_UNREACH_PORT:
1078 if (ip->ip_ttl <= 1)
1083 case ICMP_UNREACH_NET:
1084 #if ENABLE_TRACEROUTE6 && (ICMP6_DST_UNREACH_NOROUTE != ICMP_UNREACH_NET)
1085 case ICMP6_DST_UNREACH_NOROUTE << 8:
1090 case ICMP_UNREACH_HOST:
1091 #if ENABLE_TRACEROUTE6
1092 case ICMP6_DST_UNREACH_ADDR << 8:
1097 case ICMP_UNREACH_PROTOCOL:
1101 case ICMP_UNREACH_NEEDFRAG:
1102 printf(" !F-%d", pmtu);
1105 case ICMP_UNREACH_SRCFAIL:
1106 #if ENABLE_TRACEROUTE6
1107 case ICMP6_DST_UNREACH_ADMIN << 8:
1112 case ICMP_UNREACH_FILTER_PROHIB:
1113 case ICMP_UNREACH_NET_PROHIB: /* misuse */
1117 case ICMP_UNREACH_HOST_PROHIB:
1121 case ICMP_UNREACH_HOST_PRECEDENCE:
1125 case ICMP_UNREACH_PRECEDENCE_CUTOFF:
1129 case ICMP_UNREACH_NET_UNKNOWN:
1130 case ICMP_UNREACH_HOST_UNKNOWN:
1134 case ICMP_UNREACH_ISOLATED:
1138 case ICMP_UNREACH_TOSNET:
1139 case ICMP_UNREACH_TOSHOST:
1144 printf(" !<%d>", icmp_code);
1149 } /* while (wait and read a packet) */
1151 /* there was no packet at all? */
1154 } /* for (nprobes) */
1158 || (unreachable > 0 && unreachable >= nprobes - 1)
1164 if (ENABLE_FEATURE_CLEAN_UP) {
1173 int traceroute_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
1174 int traceroute_main(int argc UNUSED_PARAM, char **argv)
1176 return common_traceroute_main(0, argv);
1179 #if ENABLE_TRACEROUTE6
1180 int traceroute6_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
1181 int traceroute6_main(int argc UNUSED_PARAM, char **argv)
1183 return common_traceroute_main(OPT_IPV6, argv);