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
212 //config:config TRACEROUTE
213 //config: bool "traceroute"
215 //config: select PLATFORM_LINUX
217 //config: Utility to trace the route of IP packets.
219 //config:config TRACEROUTE6
220 //config: bool "traceroute6"
222 //config: depends on FEATURE_IPV6
224 //config: Utility to trace the route of IPv6 packets.
226 //config:config FEATURE_TRACEROUTE_VERBOSE
227 //config: bool "Enable verbose output"
229 //config: depends on TRACEROUTE || TRACEROUTE6
231 //config: Add some verbosity to traceroute. This includes among other things
232 //config: hostnames and ICMP response types.
234 //config:config FEATURE_TRACEROUTE_USE_ICMP
235 //config: bool "Enable -I option (use ICMP instead of UDP)"
237 //config: depends on TRACEROUTE || TRACEROUTE6
239 /* Needs socket(AF_INET, SOCK_RAW, IPPROTO_ICMP), therefore BB_SUID_MAYBE: */
240 //applet:IF_TRACEROUTE(APPLET(traceroute, BB_DIR_USR_BIN, BB_SUID_MAYBE))
241 //applet:IF_TRACEROUTE6(APPLET(traceroute6, BB_DIR_USR_BIN, BB_SUID_MAYBE))
243 //kbuild:lib-$(CONFIG_TRACEROUTE) += traceroute.o
244 //kbuild:lib-$(CONFIG_TRACEROUTE6) += traceroute.o
246 //usage:#define traceroute_trivial_usage
247 //usage: "[-"IF_TRACEROUTE6("46")"FIlnrv] [-f 1ST_TTL] [-m MAXTTL] [-q PROBES] [-p PORT]\n"
248 //usage: " [-t TOS] [-w WAIT_SEC] [-s SRC_IP] [-i IFACE]\n"
249 //usage: " [-z PAUSE_MSEC] HOST [BYTES]"
250 //usage:#define traceroute_full_usage "\n\n"
251 //usage: "Trace the route to HOST\n"
252 //usage: IF_TRACEROUTE6(
253 //usage: "\n -4,-6 Force IP or IPv6 name resolution"
255 //usage: "\n -F Set don't fragment bit"
256 //usage: IF_FEATURE_TRACEROUTE_USE_ICMP(
257 //usage: "\n -I Use ICMP ECHO instead of UDP datagrams"
259 //usage: "\n -l Display TTL value of the returned packet"
260 //Currently disabled (TRACEROUTE_SO_DEBUG==0)
261 ////usage: "\n -d Set SO_DEBUG options to socket"
262 //usage: "\n -n Print numeric addresses"
263 //usage: "\n -r Bypass routing tables, send directly to HOST"
264 //usage: IF_FEATURE_TRACEROUTE_VERBOSE(
265 //usage: "\n -v Verbose"
267 //usage: "\n -f N First number of hops (default 1)"
268 //usage: "\n -m N Max number of hops"
269 //usage: "\n -q N Number of probes per hop (default 3)"
270 //usage: "\n -p N Base UDP port number used in probes"
271 //usage: "\n (default 33434)"
272 //usage: "\n -s IP Source address"
273 //usage: "\n -i IFACE Source interface"
274 //usage: "\n -t N Type-of-service in probe packets (default 0)"
275 //usage: "\n -w SEC Time to wait for a response (default 3)"
276 //usage: "\n -g IP Loose source route gateway (8 max)"
278 //usage:#define traceroute6_trivial_usage
279 //usage: "[-nrv] [-m MAXTTL] [-q PROBES] [-p PORT]\n"
280 //usage: " [-t TOS] [-w WAIT_SEC] [-s SRC_IP] [-i IFACE]\n"
281 //usage: " HOST [BYTES]"
282 //usage:#define traceroute6_full_usage "\n\n"
283 //usage: "Trace the route to HOST\n"
284 //Currently disabled (TRACEROUTE_SO_DEBUG==0)
285 ////usage: "\n -d Set SO_DEBUG options to socket"
286 //usage: "\n -n Print numeric addresses"
287 //usage: "\n -r Bypass routing tables, send directly to HOST"
288 //usage: IF_FEATURE_TRACEROUTE_VERBOSE(
289 //usage: "\n -v Verbose"
291 //usage: "\n -m N Max number of hops"
292 //usage: "\n -q N Number of probes per hop (default 3)"
293 //usage: "\n -p N Base UDP port number used in probes"
294 //usage: "\n (default 33434)"
295 //usage: "\n -s IP Source address"
296 //usage: "\n -i IFACE Source interface"
297 //usage: "\n -t N Type-of-service in probe packets (default 0)"
298 //usage: "\n -w SEC Time wait for a response (default 3)"
300 #define TRACEROUTE_SO_DEBUG 0
303 #include <arpa/inet.h>
304 #include <netinet/in.h>
305 #include <netinet/udp.h>
306 #include <netinet/ip.h>
307 #include <netinet/ip_icmp.h>
308 #if ENABLE_FEATURE_IPV6
309 # include <netinet/ip6.h>
310 # include <netinet/icmp6.h>
312 # define SOL_IPV6 IPPROTO_IPV6
317 #include "inet_common.h"
320 # define IPPROTO_ICMP 1
323 # define IPPROTO_IP 0
328 "FIlnrdvxt:i:m:p:q:s:w:z:f:" \
329 "4" IF_TRACEROUTE6("6")
331 OPT_DONT_FRAGMNT = (1 << 0), /* F */
332 OPT_USE_ICMP = (1 << 1) * ENABLE_FEATURE_TRACEROUTE_USE_ICMP, /* I */
333 OPT_TTL_FLAG = (1 << 2), /* l */
334 OPT_ADDR_NUM = (1 << 3), /* n */
335 OPT_BYPASS_ROUTE = (1 << 4), /* r */
336 OPT_DEBUG = (1 << 5), /* d */
337 OPT_VERBOSE = (1 << 6) * ENABLE_FEATURE_TRACEROUTE_VERBOSE, /* v */
338 OPT_IP_CHKSUM = (1 << 7), /* x */
339 OPT_TOS = (1 << 8), /* t */
340 OPT_DEVICE = (1 << 9), /* i */
341 OPT_MAX_TTL = (1 << 10), /* m */
342 OPT_PORT = (1 << 11), /* p */
343 OPT_NPROBES = (1 << 12), /* q */
344 OPT_SOURCE = (1 << 13), /* s */
345 OPT_WAITTIME = (1 << 14), /* w */
346 OPT_PAUSE_MS = (1 << 15), /* z */
347 OPT_FIRST_TTL = (1 << 16), /* f */
348 OPT_IPV4 = (1 << 17), /* 4 */
349 OPT_IPV6 = (1 << 18) * ENABLE_TRACEROUTE6, /* 6 */
351 #define verbose (option_mask32 & OPT_VERBOSE)
355 rcvsock = 3, /* receive (icmp) socket file descriptor */
356 sndsock = 4, /* send (udp/icmp) socket file descriptor */
359 /* Data section of the probe packet */
361 unsigned char seq; /* sequence number of this packet */
362 unsigned char ttl; /* ttl packet left with */
363 // UNUSED. Retaining to have the same packet size.
364 struct timeval tv_UNUSED PACKED; /* time packet left */
367 #if ENABLE_TRACEROUTE6
371 struct timeval tv_UNUSED PACKED; /* time packet left */
376 /* Pointer to entire malloced IP packet, "packlen" bytes long: */
378 /* Pointer to ICMP or UDP payload (not header): */
379 struct outdata_t *outdata;
381 len_and_sockaddr *dest_lsa;
382 int packlen; /* total length of packet */
383 int pmtu; /* Path MTU Discovery (RFC1191) */
385 uint16_t port; // 33434; /* start udp dest port # for probe packets */
386 int waittime; // 5; /* time to wait for response (in seconds) */
387 unsigned char recv_pkt[512]; /* last inbound (icmp) packet */
390 #define G (*ptr_to_globals)
391 #define outip (G.outip )
392 #define outdata (G.outdata )
393 #define dest_lsa (G.dest_lsa )
394 #define packlen (G.packlen )
395 #define pmtu (G.pmtu )
396 #define ident (G.ident )
397 #define port (G.port )
398 #define waittime (G.waittime )
399 #define recv_pkt (G.recv_pkt )
400 #define gwlist (G.gwlist )
401 #define INIT_G() do { \
402 SET_PTR_TO_GLOBALS(xzalloc(sizeof(G))); \
407 #define outicmp ((struct icmp *)(outip + 1))
408 #define outudp ((struct udphdr *)(outip + 1))
412 wait_for_reply(len_and_sockaddr *from_lsa, struct sockaddr *to, unsigned *timestamp_us, int *left_ms)
414 struct pollfd pfd[1];
418 pfd[0].events = POLLIN;
419 if (*left_ms >= 0 && safe_poll(pfd, 1, *left_ms) > 0) {
422 read_len = recv_from_to(rcvsock,
423 recv_pkt, sizeof(recv_pkt),
424 /*flags:*/ MSG_DONTWAIT,
425 &from_lsa->u.sa, to, from_lsa->len);
427 *left_ms -= (t - *timestamp_us) / 1000;
435 send_probe(int seq, int ttl)
441 #if ENABLE_TRACEROUTE6
442 if (dest_lsa->u.sa.sa_family == AF_INET6) {
443 struct outdata6_t *pkt = (struct outdata6_t *) outdata;
444 pkt->ident6 = htonl(ident);
445 pkt->seq6 = htonl(seq);
446 /*gettimeofday(&pkt->tv, &tz);*/
452 // UNUSED: was storing gettimeofday's result there, but never ever checked it
453 /*memcpy(&outdata->tv, tp, sizeof(outdata->tv));*/
455 if (option_mask32 & OPT_USE_ICMP) {
456 outicmp->icmp_seq = htons(seq);
458 /* Always calculate checksum for icmp packets */
459 outicmp->icmp_cksum = 0;
460 outicmp->icmp_cksum = inet_cksum(
462 ((char*)outip + packlen) - (char*)outicmp
464 if (outicmp->icmp_cksum == 0)
465 outicmp->icmp_cksum = 0xffff;
469 //BUG! verbose is (x & OPT_VERBOSE), not a counter!
470 #if 0 //ENABLE_FEATURE_TRACEROUTE_VERBOSE
471 /* XXX undocumented debugging hack */
476 sp = (uint16_t *)outip;
477 nshorts = (unsigned)packlen / sizeof(uint16_t);
479 printf("[ %d bytes", packlen);
480 while (--nshorts >= 0) {
483 printf(" %04x", ntohs(*sp));
489 printf(" %02x", *(unsigned char *)sp);
496 #if ENABLE_TRACEROUTE6
497 if (dest_lsa->u.sa.sa_family == AF_INET6) {
498 res = setsockopt_int(sndsock, SOL_IPV6, IPV6_UNICAST_HOPS, ttl);
500 bb_perror_msg_and_die("setsockopt(%s) %d", "UNICAST_HOPS", ttl);
505 res = setsockopt_int(sndsock, IPPROTO_IP, IP_TTL, ttl);
507 bb_perror_msg_and_die("setsockopt(%s) %d", "TTL", ttl);
509 if (option_mask32 & OPT_USE_ICMP)
513 if (!(option_mask32 & OPT_USE_ICMP)) {
514 set_nport(&dest_lsa->u.sa, htons(port + seq));
516 len = ((char*)outip + packlen) - (char*)out;
517 res = xsendto(sndsock, out, len, &dest_lsa->u.sa, dest_lsa->len);
519 bb_error_msg("sent %d octets, ret=%d", len, res);
522 #if ENABLE_FEATURE_TRACEROUTE_VERBOSE
524 * Convert an ICMP "type" field to a printable string.
527 pr_type(unsigned char t)
529 static const char *const ttab[] = {
530 "Echo Reply", "ICMP 1", "ICMP 2", "Dest Unreachable",
531 "Source Quench", "Redirect", "ICMP 6", "ICMP 7",
532 "Echo", "Router Advert", "Router Solicit", "Time Exceeded",
533 "Param Problem", "Timestamp", "Timestamp Reply", "Info Request",
534 "Info Reply", "Mask Request", "Mask Reply"
536 # if ENABLE_TRACEROUTE6
537 static const char *const ttab6[] = {
538 [0] "Error", "Dest Unreachable", "Packet Too Big", "Time Exceeded",
540 [8] "Echo Request", "Echo Reply", "Membership Query", "Membership Report",
541 [12] "Membership Reduction", "Router Solicit", "Router Advert", "Neighbor Solicit",
542 [16] "Neighbor Advert", "Redirect",
545 if (dest_lsa->u.sa.sa_family == AF_INET6) {
548 if (t < 128 || t > ND_REDIRECT)
549 return "OUT-OF-RANGE";
550 return ttab6[(t & 63) + 8];
553 if (t >= ARRAY_SIZE(ttab))
554 return "OUT-OF-RANGE";
560 #if !ENABLE_FEATURE_TRACEROUTE_VERBOSE
561 #define packet4_ok(read_len, from, seq) \
562 packet4_ok(read_len, seq)
565 packet4_ok(int read_len, const struct sockaddr_in *from, int seq)
567 const struct icmp *icp;
568 unsigned char type, code;
572 ip = (struct ip *) recv_pkt;
573 hlen = ip->ip_hl << 2;
574 if (read_len < hlen + ICMP_MINLEN) {
575 #if ENABLE_FEATURE_TRACEROUTE_VERBOSE
577 printf("packet too short (%d bytes) from %s\n", read_len,
578 inet_ntoa(from->sin_addr));
583 icp = (struct icmp *)(recv_pkt + hlen);
584 type = icp->icmp_type;
585 code = icp->icmp_code;
586 /* Path MTU Discovery (RFC1191) */
588 if (code == ICMP_UNREACH_NEEDFRAG)
589 pmtu = ntohs(icp->icmp_nextmtu);
591 if ((type == ICMP_TIMXCEED && code == ICMP_TIMXCEED_INTRANS)
592 || type == ICMP_UNREACH
593 || type == ICMP_ECHOREPLY
595 const struct ip *hip;
596 const struct udphdr *up;
599 hlen = hip->ip_hl << 2;
600 if (option_mask32 & OPT_USE_ICMP) {
604 if (type == ICMP_ECHOREPLY
605 && icp->icmp_id == htons(ident)
606 && icp->icmp_seq == htons(seq)
608 return ICMP_UNREACH_PORT+1;
611 hicmp = (struct icmp *)((unsigned char *)hip + hlen);
612 if (hlen + SIZEOF_ICMP_HDR <= read_len
613 && hip->ip_p == IPPROTO_ICMP
614 && hicmp->icmp_id == htons(ident)
615 && hicmp->icmp_seq == htons(seq)
617 return (type == ICMP_TIMXCEED ? -1 : code + 1);
620 up = (struct udphdr *)((char *)hip + hlen);
621 if (hlen + 12 <= read_len
622 && hip->ip_p == IPPROTO_UDP
623 // Off: since we do not form the entire IP packet,
624 // but defer it to kernel, we can't set source port,
625 // and thus can't check it here in the reply
626 /* && up->source == htons(ident) */
627 && up->dest == htons(port + seq)
629 return (type == ICMP_TIMXCEED ? -1 : code + 1);
633 #if ENABLE_FEATURE_TRACEROUTE_VERBOSE
636 uint32_t *lp = (uint32_t *)&icp->icmp_ip;
638 printf("\n%d bytes from %s to "
639 "%s: icmp type %d (%s) code %d\n",
640 read_len, inet_ntoa(from->sin_addr),
641 inet_ntoa(ip->ip_dst),
642 type, pr_type(type), icp->icmp_code);
643 for (i = 4; i < read_len; i += sizeof(*lp))
644 printf("%2d: x%8.8x\n", i, *lp++);
650 #if ENABLE_TRACEROUTE6
651 # if !ENABLE_FEATURE_TRACEROUTE_VERBOSE
652 #define packet_ok(read_len, from_lsa, to, seq) \
653 packet_ok(read_len, from_lsa, seq)
656 packet_ok(int read_len, len_and_sockaddr *from_lsa,
660 const struct icmp6_hdr *icp;
661 unsigned char type, code;
663 if (from_lsa->u.sa.sa_family == AF_INET)
664 return packet4_ok(read_len, &from_lsa->u.sin, seq);
666 icp = (struct icmp6_hdr *) recv_pkt;
668 type = icp->icmp6_type;
669 code = icp->icmp6_code;
671 if ((type == ICMP6_TIME_EXCEEDED && code == ICMP6_TIME_EXCEED_TRANSIT)
672 || type == ICMP6_DST_UNREACH
678 hip = (struct ip6_hdr *)(icp + 1);
679 up = (struct udphdr *) (hip + 1);
680 nexthdr = hip->ip6_nxt;
682 if (nexthdr == IPPROTO_FRAGMENT) {
683 nexthdr = *(unsigned char*)up;
686 if (nexthdr == IPPROTO_UDP) {
687 struct outdata6_t *pkt;
689 pkt = (struct outdata6_t *) (up + 1);
691 if (ntohl(pkt->ident6) == ident
692 && ntohl(pkt->seq6) == seq
694 return (type == ICMP6_TIME_EXCEEDED ? -1 : (code<<8)+1);
699 # if ENABLE_FEATURE_TRACEROUTE_VERBOSE
702 char pa1[MAXHOSTNAMELEN];
703 char pa2[MAXHOSTNAMELEN];
706 p = (unsigned char *) (icp + 1);
708 printf("\n%d bytes from %s to "
709 "%s: icmp type %d (%s) code %d\n",
711 inet_ntop(AF_INET6, &from_lsa->u.sin6.sin6_addr, pa1, sizeof(pa1)),
712 inet_ntop(AF_INET6, &((struct sockaddr_in6*)to)->sin6_addr, pa2, sizeof(pa2)),
713 type, pr_type(type), icp->icmp6_code);
715 read_len -= sizeof(struct icmp6_hdr);
716 for (i = 0; i < read_len; i++) {
721 printf("%02x", p[i]);
722 if ((i % 16 == 15) && (i + 1 < read_len))
731 #else /* !ENABLE_TRACEROUTE6 */
732 static ALWAYS_INLINE int
733 packet_ok(int read_len,
734 len_and_sockaddr *from_lsa IF_NOT_FEATURE_TRACEROUTE_VERBOSE(UNUSED_PARAM),
735 struct sockaddr *to UNUSED_PARAM,
738 return packet4_ok(read_len, &from_lsa->u.sin, seq);
743 * Construct an Internet address representation.
744 * If the -n flag has been supplied, give
745 * numeric value, otherwise try for symbolic name.
748 print_inetname(const struct sockaddr *from)
750 char *ina = xmalloc_sockaddr2dotted_noport(from);
752 if (option_mask32 & OPT_ADDR_NUM) {
757 if (from->sa_family != AF_INET
758 || ((struct sockaddr_in*)from)->sin_addr.s_addr != INADDR_ANY
760 /* Try to reverse resolve if it is not 0.0.0.0 */
761 n = xmalloc_sockaddr2host_noport((struct sockaddr*)from);
763 printf(" %s (%s)", (n ? n : ina), ina);
770 print(int read_len, const struct sockaddr *from, const struct sockaddr *to)
772 print_inetname(from);
775 char *ina = xmalloc_sockaddr2dotted_noport(to);
776 #if ENABLE_TRACEROUTE6
777 if (to->sa_family == AF_INET6) {
778 read_len -= sizeof(struct ip6_hdr);
782 struct ip *ip4packet = (struct ip*)recv_pkt;
783 read_len -= ip4packet->ip_hl << 2;
785 printf(" %d bytes to %s", read_len, ina);
791 print_delta_ms(unsigned t1p, unsigned t2p)
793 unsigned tt = t2p - t1p;
794 printf(" %u.%03u ms", tt / 1000, tt % 1000);
798 * Usage: [-dFIlnrvx] [-g gateway] [-i iface] [-f first_ttl]
799 * [-m max_ttl] [ -p port] [-q nqueries] [-s src_addr] [-t tos]
800 * [-w waittime] [-z pausemsecs] host [packetlen]"
803 common_traceroute_main(int op, char **argv)
812 unsigned pausemsecs = 0;
820 char *pausemsecs_str;
823 #if ENABLE_TRACEROUTE6
826 enum { af = AF_INET };
830 len_and_sockaddr *from_lsa;
831 struct sockaddr *lastaddr;
837 opt_complementary = "-1:x-x";
838 op |= getopt32(argv, OPT_STRING
839 , &tos_str, &device, &max_ttl_str, &port_str, &nprobes_str
840 , &source, &waittime_str, &pausemsecs_str, &first_ttl_str
845 if (op & OPT_IP_CHKSUM)
846 bb_error_msg("warning: ip checksums disabled");
850 tos = xatou_range(tos_str, 0, 255);
852 if (op & OPT_MAX_TTL)
853 max_ttl = xatou_range(max_ttl_str, 1, 255);
855 port = xatou16(port_str);
856 if (op & OPT_NPROBES)
857 nprobes = xatou_range(nprobes_str, 1, INT_MAX);
858 if (op & OPT_SOURCE) {
860 * set the ip source address of the outbound
861 * probe (e.g., on a multi-homed host).
864 bb_error_msg_and_die(bb_msg_you_must_be_root);
866 if (op & OPT_WAITTIME)
867 waittime = xatou_range(waittime_str, 1, 24 * 60 * 60);
868 if (op & OPT_PAUSE_MS)
869 pausemsecs = xatou_range(pausemsecs_str, 0, 60 * 60 * 1000);
870 if (op & OPT_FIRST_TTL)
871 first_ttl = xatou_range(first_ttl_str, 1, max_ttl);
873 /* Process destination and optional packet size */
874 minpacket = sizeof(struct ip)
876 + sizeof(struct outdata_t);
877 if (!(op & OPT_USE_ICMP))
878 minpacket = sizeof(struct ip)
879 + sizeof(struct udphdr)
880 + sizeof(struct outdata_t);
881 #if ENABLE_TRACEROUTE6
887 dest_lsa = xhost_and_af2sockaddr(argv[0], port, af);
888 af = dest_lsa->u.sa.sa_family;
890 minpacket = sizeof(struct ip6_hdr)
891 + sizeof(struct udphdr)
892 + sizeof(struct outdata6_t);
894 dest_lsa = xhost2sockaddr(argv[0], port);
898 packlen = xatoul_range(argv[1], minpacket, 32 * 1024);
900 /* Ensure the socket fds won't be 0, 1 or 2 */
903 #if ENABLE_TRACEROUTE6
904 if (af == AF_INET6) {
905 xmove_fd(xsocket(AF_INET6, SOCK_RAW, IPPROTO_ICMPV6), rcvsock);
906 # ifdef IPV6_RECVPKTINFO
907 setsockopt_1(rcvsock, SOL_IPV6, IPV6_RECVPKTINFO);
908 setsockopt_1(rcvsock, SOL_IPV6, IPV6_2292PKTINFO);
910 setsockopt_1(rcvsock, SOL_IPV6, IPV6_PKTINFO);
915 xmove_fd(xsocket(AF_INET, SOCK_RAW, IPPROTO_ICMP), rcvsock);
918 #if TRACEROUTE_SO_DEBUG
920 setsockopt_SOL_SOCKET_1(rcvsock, SO_DEBUG);
922 if (op & OPT_BYPASS_ROUTE)
923 setsockopt_SOL_SOCKET_1(rcvsock, SO_DONTROUTE);
925 #if ENABLE_TRACEROUTE6
926 if (af == AF_INET6) {
927 if (setsockopt_int(rcvsock, SOL_RAW, IPV6_CHECKSUM, 2) != 0)
928 bb_perror_msg_and_die("setsockopt(%s)", "IPV6_CHECKSUM");
929 xmove_fd(xsocket(af, SOCK_DGRAM, 0), sndsock);
933 if (op & OPT_USE_ICMP)
934 xmove_fd(xsocket(AF_INET, SOCK_RAW, IPPROTO_ICMP), sndsock);
936 xmove_fd(xsocket(AF_INET, SOCK_DGRAM, 0), sndsock);
940 if (setsockopt_SOL_SOCKET_int(sndsock, SO_SNDBUF, packlen) != 0) {
941 bb_perror_msg_and_die("setsockopt(%s)", "SO_SNDBUF");
945 if ((op & OPT_TOS) && setsockopt_int(sndsock, IPPROTO_IP, IP_TOS, tos) != 0) {
946 bb_perror_msg_and_die("setsockopt(%s) %d", "TOS", tos);
950 if (op & OPT_DONT_FRAGMNT)
951 setsockopt_1(sndsock, IPPROTO_IP, IP_DONTFRAG);
953 #if TRACEROUTE_SO_DEBUG
955 setsockopt_SOL_SOCKET_1(sndsock, SO_DEBUG);
957 if (op & OPT_BYPASS_ROUTE)
958 setsockopt_SOL_SOCKET_1(sndsock, SO_DONTROUTE);
960 outip = xzalloc(packlen);
964 if (!ENABLE_TRACEROUTE6 || af == AF_INET) {
965 if (op & OPT_USE_ICMP) {
967 outicmp->icmp_type = ICMP_ECHO;
968 outicmp->icmp_id = htons(ident);
969 outdata = (struct outdata_t *)((char *)outicmp + SIZEOF_ICMP_HDR);
971 outdata = (struct outdata_t *)(outudp + 1);
974 #if ENABLE_TRACEROUTE6
975 if (af == AF_INET6) {
976 outdata = (void*)((char*)outip
977 + sizeof(struct ip6_hdr)
978 + sizeof(struct udphdr)
983 if (op & OPT_DEVICE) /* hmm, do we need error check? */
984 setsockopt_bindtodevice(sndsock, device);
986 if (op & OPT_SOURCE) {
987 #if ENABLE_TRACEROUTE6
988 // TODO: need xdotted_and_af2sockaddr?
989 len_and_sockaddr *source_lsa = xhost_and_af2sockaddr(source, 0, af);
991 len_and_sockaddr *source_lsa = xdotted2sockaddr(source, 0);
993 /* Ping4 does this (why?) */
995 if (setsockopt(sndsock, IPPROTO_IP, IP_MULTICAST_IF,
996 &source_lsa->u.sa, source_lsa->len))
997 bb_error_msg_and_die("can't set multicast source interface");
998 //TODO: we can query source port we bound to,
999 // and check it in replies... if we care enough
1000 xbind(sndsock, &source_lsa->u.sa, source_lsa->len);
1003 #if ENABLE_TRACEROUTE6
1004 else if (af == AF_INET6) {
1005 //TODO: why we don't do it for IPv4?
1006 len_and_sockaddr *source_lsa;
1008 int probe_fd = xsocket(af, SOCK_DGRAM, 0);
1009 if (op & OPT_DEVICE)
1010 setsockopt_bindtodevice(probe_fd, device);
1011 set_nport(&dest_lsa->u.sa, htons(1025));
1012 /* dummy connect. makes kernel pick source IP (and port) */
1013 xconnect(probe_fd, &dest_lsa->u.sa, dest_lsa->len);
1014 set_nport(&dest_lsa->u.sa, htons(port));
1016 /* read IP and port */
1017 source_lsa = get_sock_lsa(probe_fd);
1018 if (source_lsa == NULL)
1019 bb_error_msg_and_die("can't get probe addr");
1023 /* bind our sockets to this IP (but not port) */
1024 set_nport(&source_lsa->u.sa, 0);
1025 xbind(sndsock, &source_lsa->u.sa, source_lsa->len);
1026 xbind(rcvsock, &source_lsa->u.sa, source_lsa->len);
1032 /* Revert to non-privileged user after opening sockets */
1036 dest_str = xmalloc_sockaddr2dotted_noport(&dest_lsa->u.sa);
1037 printf("traceroute to %s (%s)", argv[0], dest_str);
1038 if (ENABLE_FEATURE_CLEAN_UP) {
1042 if (op & OPT_SOURCE)
1043 printf(" from %s", source);
1044 printf(", %d hops max, %d byte packets\n", max_ttl, packlen);
1046 from_lsa = xmemdup(dest_lsa, LSA_LEN_SIZE + dest_lsa->len);
1047 lastaddr = xzalloc(dest_lsa->len);
1048 to = xzalloc(dest_lsa->len);
1050 for (ttl = first_ttl; ttl <= max_ttl; ++ttl) {
1052 int unreachable = 0; /* counter */
1053 int gotlastaddr = 0; /* flags */
1057 for (probe = 0; probe < nprobes; ++probe) {
1065 if (probe != 0 && pausemsecs > 0)
1066 usleep(pausemsecs * 1000);
1068 send_probe(++seq, ttl);
1069 t2 = t1 = monotonic_us();
1071 left_ms = waittime * 1000;
1072 while ((read_len = wait_for_reply(from_lsa, to, &t2, &left_ms)) != 0) {
1075 /* Recv'ed a packet, or read error */
1076 /* t2 = monotonic_us() - set by wait_for_reply */
1080 icmp_code = packet_ok(read_len, from_lsa, to, seq);
1081 /* Skip short packet */
1086 || (memcmp(lastaddr, &from_lsa->u.sa, from_lsa->len) != 0)
1088 print(read_len, &from_lsa->u.sa, to);
1089 memcpy(lastaddr, &from_lsa->u.sa, from_lsa->len);
1093 print_delta_ms(t1, t2);
1094 ip = (struct ip *)recv_pkt;
1096 if (from_lsa->u.sa.sa_family == AF_INET)
1097 if (op & OPT_TTL_FLAG)
1098 printf(" (%d)", ip->ip_ttl);
1100 /* time exceeded in transit */
1101 if (icmp_code == -1)
1104 switch (icmp_code) {
1105 #if ENABLE_TRACEROUTE6
1106 case ICMP6_DST_UNREACH_NOPORT << 8:
1110 case ICMP_UNREACH_PORT:
1111 if (ip->ip_ttl <= 1)
1116 case ICMP_UNREACH_NET:
1117 #if ENABLE_TRACEROUTE6 && (ICMP6_DST_UNREACH_NOROUTE != ICMP_UNREACH_NET)
1118 case ICMP6_DST_UNREACH_NOROUTE << 8:
1123 case ICMP_UNREACH_HOST:
1124 #if ENABLE_TRACEROUTE6
1125 case ICMP6_DST_UNREACH_ADDR << 8:
1130 case ICMP_UNREACH_PROTOCOL:
1134 case ICMP_UNREACH_NEEDFRAG:
1135 printf(" !F-%d", pmtu);
1138 case ICMP_UNREACH_SRCFAIL:
1139 #if ENABLE_TRACEROUTE6
1140 case ICMP6_DST_UNREACH_ADMIN << 8:
1145 case ICMP_UNREACH_FILTER_PROHIB:
1146 case ICMP_UNREACH_NET_PROHIB: /* misuse */
1150 case ICMP_UNREACH_HOST_PROHIB:
1154 case ICMP_UNREACH_HOST_PRECEDENCE:
1158 case ICMP_UNREACH_PRECEDENCE_CUTOFF:
1162 case ICMP_UNREACH_NET_UNKNOWN:
1163 case ICMP_UNREACH_HOST_UNKNOWN:
1167 case ICMP_UNREACH_ISOLATED:
1171 case ICMP_UNREACH_TOSNET:
1172 case ICMP_UNREACH_TOSHOST:
1177 printf(" !<%d>", icmp_code);
1182 } /* while (wait and read a packet) */
1184 /* there was no packet at all? */
1187 } /* for (nprobes) */
1191 || (unreachable > 0 && unreachable >= nprobes - 1)
1197 if (ENABLE_FEATURE_CLEAN_UP) {
1206 #if ENABLE_TRACEROUTE
1207 int traceroute_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
1208 int traceroute_main(int argc UNUSED_PARAM, char **argv)
1210 return common_traceroute_main(0, argv);
1214 #if ENABLE_TRACEROUTE6
1215 int traceroute6_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
1216 int traceroute6_main(int argc UNUSED_PARAM, char **argv)
1218 return common_traceroute_main(OPT_IPV6, argv);