Contents of /tags/mkinitrd-6_1_9/busybox/networking/traceroute.c
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Wed Oct 28 00:26:51 2009 UTC (14 years, 11 months ago) by niro
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tagged 'mkinitrd-6_1_9'
1 | /* vi: set sw=4 ts=4: */ |
2 | /* |
3 | * Copyright (c) 1988, 1989, 1991, 1994, 1995, 1996, 1997, 1998, 1999, 2000 |
4 | * The Regents of the University of California. All rights reserved. |
5 | * |
6 | * Busybox port by Vladimir Oleynik (C) 2005 <dzo@simtreas.ru> |
7 | * |
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 |
19 | * written permission. |
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. |
23 | */ |
24 | |
25 | /* |
26 | * traceroute host - trace the route ip packets follow going to "host". |
27 | * |
28 | * Attempt to trace the route an ip packet would follow to some |
29 | * internet host. We find out intermediate hops by launching probe |
30 | * packets with a small ttl (time to live) then listening for an |
31 | * icmp "time exceeded" reply from a gateway. We start our probes |
32 | * with a ttl of one and increase by one until we get an icmp "port |
33 | * unreachable" (which means we got to "host") or hit a max (which |
34 | * defaults to 30 hops & can be changed with the -m flag). Three |
35 | * probes (change with -q flag) are sent at each ttl setting and a |
36 | * line is printed showing the ttl, address of the gateway and |
37 | * round trip time of each probe. If the probe answers come from |
38 | * different gateways, the address of each responding system will |
39 | * be printed. If there is no response within a 5 sec. timeout |
40 | * interval (changed with the -w flag), a "*" is printed for that |
41 | * probe. |
42 | * |
43 | * Probe packets are UDP format. We don't want the destination |
44 | * host to process them so the destination port is set to an |
45 | * unlikely value (if some clod on the destination is using that |
46 | * value, it can be changed with the -p flag). |
47 | * |
48 | * A sample use might be: |
49 | * |
50 | * [yak 71]% traceroute nis.nsf.net. |
51 | * traceroute to nis.nsf.net (35.1.1.48), 30 hops max, 56 byte packet |
52 | * 1 helios.ee.lbl.gov (128.3.112.1) 19 ms 19 ms 0 ms |
53 | * 2 lilac-dmc.Berkeley.EDU (128.32.216.1) 39 ms 39 ms 19 ms |
54 | * 3 lilac-dmc.Berkeley.EDU (128.32.216.1) 39 ms 39 ms 19 ms |
55 | * 4 ccngw-ner-cc.Berkeley.EDU (128.32.136.23) 39 ms 40 ms 39 ms |
56 | * 5 ccn-nerif22.Berkeley.EDU (128.32.168.22) 39 ms 39 ms 39 ms |
57 | * 6 128.32.197.4 (128.32.197.4) 40 ms 59 ms 59 ms |
58 | * 7 131.119.2.5 (131.119.2.5) 59 ms 59 ms 59 ms |
59 | * 8 129.140.70.13 (129.140.70.13) 99 ms 99 ms 80 ms |
60 | * 9 129.140.71.6 (129.140.71.6) 139 ms 239 ms 319 ms |
61 | * 10 129.140.81.7 (129.140.81.7) 220 ms 199 ms 199 ms |
62 | * 11 nic.merit.edu (35.1.1.48) 239 ms 239 ms 239 ms |
63 | * |
64 | * Note that lines 2 & 3 are the same. This is due to a buggy |
65 | * kernel on the 2nd hop system -- lbl-csam.arpa -- that forwards |
66 | * packets with a zero ttl. |
67 | * |
68 | * A more interesting example is: |
69 | * |
70 | * [yak 72]% traceroute allspice.lcs.mit.edu. |
71 | * traceroute to allspice.lcs.mit.edu (18.26.0.115), 30 hops max |
72 | * 1 helios.ee.lbl.gov (128.3.112.1) 0 ms 0 ms 0 ms |
73 | * 2 lilac-dmc.Berkeley.EDU (128.32.216.1) 19 ms 19 ms 19 ms |
74 | * 3 lilac-dmc.Berkeley.EDU (128.32.216.1) 39 ms 19 ms 19 ms |
75 | * 4 ccngw-ner-cc.Berkeley.EDU (128.32.136.23) 19 ms 39 ms 39 ms |
76 | * 5 ccn-nerif22.Berkeley.EDU (128.32.168.22) 20 ms 39 ms 39 ms |
77 | * 6 128.32.197.4 (128.32.197.4) 59 ms 119 ms 39 ms |
78 | * 7 131.119.2.5 (131.119.2.5) 59 ms 59 ms 39 ms |
79 | * 8 129.140.70.13 (129.140.70.13) 80 ms 79 ms 99 ms |
80 | * 9 129.140.71.6 (129.140.71.6) 139 ms 139 ms 159 ms |
81 | * 10 129.140.81.7 (129.140.81.7) 199 ms 180 ms 300 ms |
82 | * 11 129.140.72.17 (129.140.72.17) 300 ms 239 ms 239 ms |
83 | * 12 * * * |
84 | * 13 128.121.54.72 (128.121.54.72) 259 ms 499 ms 279 ms |
85 | * 14 * * * |
86 | * 15 * * * |
87 | * 16 * * * |
88 | * 17 * * * |
89 | * 18 ALLSPICE.LCS.MIT.EDU (18.26.0.115) 339 ms 279 ms 279 ms |
90 | * |
91 | * (I start to see why I'm having so much trouble with mail to |
92 | * MIT.) Note that the gateways 12, 14, 15, 16 & 17 hops away |
93 | * either don't send ICMP "time exceeded" messages or send them |
94 | * with a ttl too small to reach us. 14 - 17 are running the |
95 | * MIT C Gateway code that doesn't send "time exceeded"s. God |
96 | * only knows what's going on with 12. |
97 | * |
98 | * The silent gateway 12 in the above may be the result of a bug in |
99 | * the 4.[23]BSD network code (and its derivatives): 4.x (x <= 3) |
100 | * sends an unreachable message using whatever ttl remains in the |
101 | * original datagram. Since, for gateways, the remaining ttl is |
102 | * zero, the icmp "time exceeded" is guaranteed to not make it back |
103 | * to us. The behavior of this bug is slightly more interesting |
104 | * when it appears on the destination system: |
105 | * |
106 | * 1 helios.ee.lbl.gov (128.3.112.1) 0 ms 0 ms 0 ms |
107 | * 2 lilac-dmc.Berkeley.EDU (128.32.216.1) 39 ms 19 ms 39 ms |
108 | * 3 lilac-dmc.Berkeley.EDU (128.32.216.1) 19 ms 39 ms 19 ms |
109 | * 4 ccngw-ner-cc.Berkeley.EDU (128.32.136.23) 39 ms 40 ms 19 ms |
110 | * 5 ccn-nerif35.Berkeley.EDU (128.32.168.35) 39 ms 39 ms 39 ms |
111 | * 6 csgw.Berkeley.EDU (128.32.133.254) 39 ms 59 ms 39 ms |
112 | * 7 * * * |
113 | * 8 * * * |
114 | * 9 * * * |
115 | * 10 * * * |
116 | * 11 * * * |
117 | * 12 * * * |
118 | * 13 rip.Berkeley.EDU (128.32.131.22) 59 ms ! 39 ms ! 39 ms ! |
119 | * |
120 | * Notice that there are 12 "gateways" (13 is the final |
121 | * destination) and exactly the last half of them are "missing". |
122 | * What's really happening is that rip (a Sun-3 running Sun OS3.5) |
123 | * is using the ttl from our arriving datagram as the ttl in its |
124 | * icmp reply. So, the reply will time out on the return path |
125 | * (with no notice sent to anyone since icmp's aren't sent for |
126 | * icmp's) until we probe with a ttl that's at least twice the path |
127 | * length. I.e., rip is really only 7 hops away. A reply that |
128 | * returns with a ttl of 1 is a clue this problem exists. |
129 | * Traceroute prints a "!" after the time if the ttl is <= 1. |
130 | * Since vendors ship a lot of obsolete (DEC's Ultrix, Sun 3.x) or |
131 | * non-standard (HPUX) software, expect to see this problem |
132 | * frequently and/or take care picking the target host of your |
133 | * probes. |
134 | * |
135 | * Other possible annotations after the time are !H, !N, !P (got a host, |
136 | * network or protocol unreachable, respectively), !S or !F (source |
137 | * route failed or fragmentation needed -- neither of these should |
138 | * ever occur and the associated gateway is busted if you see one). If |
139 | * almost all the probes result in some kind of unreachable, traceroute |
140 | * will give up and exit. |
141 | * |
142 | * Notes |
143 | * ----- |
144 | * This program must be run by root or be setuid. (I suggest that |
145 | * you *don't* make it setuid -- casual use could result in a lot |
146 | * of unnecessary traffic on our poor, congested nets.) |
147 | * |
148 | * This program requires a kernel mod that does not appear in any |
149 | * system available from Berkeley: A raw ip socket using proto |
150 | * IPPROTO_RAW must interpret the data sent as an ip datagram (as |
151 | * opposed to data to be wrapped in a ip datagram). See the README |
152 | * file that came with the source to this program for a description |
153 | * of the mods I made to /sys/netinet/raw_ip.c. Your mileage may |
154 | * vary. But, again, ANY 4.x (x < 4) BSD KERNEL WILL HAVE TO BE |
155 | * MODIFIED TO RUN THIS PROGRAM. |
156 | * |
157 | * The udp port usage may appear bizarre (well, ok, it is bizarre). |
158 | * The problem is that an icmp message only contains 8 bytes of |
159 | * data from the original datagram. 8 bytes is the size of a udp |
160 | * header so, if we want to associate replies with the original |
161 | * datagram, the necessary information must be encoded into the |
162 | * udp header (the ip id could be used but there's no way to |
163 | * interlock with the kernel's assignment of ip id's and, anyway, |
164 | * it would have taken a lot more kernel hacking to allow this |
165 | * code to set the ip id). So, to allow two or more users to |
166 | * use traceroute simultaneously, we use this task's pid as the |
167 | * source port (the high bit is set to move the port number out |
168 | * of the "likely" range). To keep track of which probe is being |
169 | * replied to (so times and/or hop counts don't get confused by a |
170 | * reply that was delayed in transit), we increment the destination |
171 | * port number before each probe. |
172 | * |
173 | * Don't use this as a coding example. I was trying to find a |
174 | * routing problem and this code sort-of popped out after 48 hours |
175 | * without sleep. I was amazed it ever compiled, much less ran. |
176 | * |
177 | * I stole the idea for this program from Steve Deering. Since |
178 | * the first release, I've learned that had I attended the right |
179 | * IETF working group meetings, I also could have stolen it from Guy |
180 | * Almes or Matt Mathis. I don't know (or care) who came up with |
181 | * the idea first. I envy the originators' perspicacity and I'm |
182 | * glad they didn't keep the idea a secret. |
183 | * |
184 | * Tim Seaver, Ken Adelman and C. Philip Wood provided bug fixes and/or |
185 | * enhancements to the original distribution. |
186 | * |
187 | * I've hacked up a round-trip-route version of this that works by |
188 | * sending a loose-source-routed udp datagram through the destination |
189 | * back to yourself. Unfortunately, SO many gateways botch source |
190 | * routing, the thing is almost worthless. Maybe one day... |
191 | * |
192 | * -- Van Jacobson (van@ee.lbl.gov) |
193 | * Tue Dec 20 03:50:13 PST 1988 |
194 | */ |
195 | |
196 | #define TRACEROUTE_SO_DEBUG 0 |
197 | |
198 | /* TODO: undefs were uncommented - ??! we have config system for that! */ |
199 | /* probably ok to remove altogether */ |
200 | //#undef CONFIG_FEATURE_TRACEROUTE_VERBOSE |
201 | //#define CONFIG_FEATURE_TRACEROUTE_VERBOSE |
202 | //#undef CONFIG_FEATURE_TRACEROUTE_SOURCE_ROUTE |
203 | //#define CONFIG_FEATURE_TRACEROUTE_SOURCE_ROUTE |
204 | //#undef CONFIG_FEATURE_TRACEROUTE_USE_ICMP |
205 | //#define CONFIG_FEATURE_TRACEROUTE_USE_ICMP |
206 | |
207 | |
208 | #include <net/if.h> |
209 | #include <arpa/inet.h> |
210 | #include <netinet/in.h> |
211 | #include <netinet/udp.h> |
212 | #include <netinet/ip.h> |
213 | #include <netinet/ip_icmp.h> |
214 | |
215 | #include "libbb.h" |
216 | #include "inet_common.h" |
217 | |
218 | |
219 | /* |
220 | * Definitions for internet protocol version 4. |
221 | * Per RFC 791, September 1981. |
222 | */ |
223 | #define IPVERSION 4 |
224 | |
225 | #ifndef IPPROTO_ICMP |
226 | /* Grrrr.... */ |
227 | #define IPPROTO_ICMP 1 |
228 | #endif |
229 | #ifndef IPPROTO_IP |
230 | #define IPPROTO_IP 0 |
231 | #endif |
232 | |
233 | /* |
234 | * Overlay for ip header used by other protocols (tcp, udp). |
235 | */ |
236 | struct ipovly { |
237 | unsigned char ih_x1[9]; /* (unused) */ |
238 | unsigned char ih_pr; /* protocol */ |
239 | short ih_len; /* protocol length */ |
240 | struct in_addr ih_src; /* source internet address */ |
241 | struct in_addr ih_dst; /* destination internet address */ |
242 | }; |
243 | |
244 | /* |
245 | * UDP kernel structures and variables. |
246 | */ |
247 | struct udpiphdr { |
248 | struct ipovly ui_i; /* overlaid ip structure */ |
249 | struct udphdr ui_u; /* udp header */ |
250 | }; |
251 | #define ui_next ui_i.ih_next |
252 | #define ui_prev ui_i.ih_prev |
253 | #define ui_x1 ui_i.ih_x1 |
254 | #define ui_pr ui_i.ih_pr |
255 | #define ui_len ui_i.ih_len |
256 | #define ui_src ui_i.ih_src |
257 | #define ui_dst ui_i.ih_dst |
258 | #define ui_sport ui_u.uh_sport |
259 | #define ui_dport ui_u.uh_dport |
260 | #define ui_ulen ui_u.uh_ulen |
261 | #define ui_sum ui_u.uh_sum |
262 | |
263 | |
264 | /* Host name and address list */ |
265 | struct hostinfo { |
266 | char *name; |
267 | int n; |
268 | uint32_t *addrs; |
269 | }; |
270 | |
271 | /* Data section of the probe packet */ |
272 | typedef struct outdata { |
273 | unsigned char seq; /* sequence number of this packet */ |
274 | unsigned char ttl; /* ttl packet left with */ |
275 | // UNUSED. Retaining to have the same packet size. |
276 | struct timeval tv_UNUSED PACKED; /* time packet left */ |
277 | } outdata_t; |
278 | |
279 | struct IFADDRLIST { |
280 | uint32_t addr; |
281 | char device[sizeof(struct ifreq)]; |
282 | }; |
283 | |
284 | |
285 | /* Keep in sync with getopt32 call! */ |
286 | #define OPT_DONT_FRAGMNT (1<<0) /* F */ |
287 | #define OPT_USE_ICMP (1<<1) /* I */ |
288 | #define OPT_TTL_FLAG (1<<2) /* l */ |
289 | #define OPT_ADDR_NUM (1<<3) /* n */ |
290 | #define OPT_BYPASS_ROUTE (1<<4) /* r */ |
291 | #define OPT_DEBUG (1<<5) /* d */ |
292 | #define OPT_VERBOSE (1<<6) /* v */ |
293 | #define OPT_IP_CHKSUM (1<<7) /* x */ |
294 | #define OPT_TOS (1<<8) /* t */ |
295 | #define OPT_DEVICE (1<<9) /* i */ |
296 | #define OPT_MAX_TTL (1<<10) /* m */ |
297 | #define OPT_PORT (1<<11) /* p */ |
298 | #define OPT_NPROBES (1<<12) /* q */ |
299 | #define OPT_SOURCE (1<<13) /* s */ |
300 | #define OPT_WAITTIME (1<<14) /* w */ |
301 | #define OPT_PAUSE_MS (1<<15) /* z */ |
302 | #define OPT_FIRST_TTL (1<<16) /* f */ |
303 | |
304 | #if ENABLE_FEATURE_TRACEROUTE_USE_ICMP |
305 | /* use icmp echo instead of udp packets */ |
306 | #define useicmp (option_mask32 & OPT_USE_ICMP) |
307 | #endif |
308 | #if ENABLE_FEATURE_TRACEROUTE_VERBOSE |
309 | #define verbose (option_mask32 & OPT_VERBOSE) |
310 | #endif |
311 | #define nflag (option_mask32 & OPT_ADDR_NUM) |
312 | |
313 | |
314 | struct globals { |
315 | struct ip *outip; /* last output (udp) packet */ |
316 | struct udphdr *outudp; /* last output (udp) packet */ |
317 | struct outdata *outdata; /* last output (udp) packet */ |
318 | |
319 | #if ENABLE_FEATURE_TRACEROUTE_USE_ICMP |
320 | struct icmp *outicmp; /* last output (icmp) packet */ |
321 | #endif |
322 | |
323 | int rcvsock; /* receive (icmp) socket file descriptor */ |
324 | int sndsock; /* send (udp/icmp) socket file descriptor */ |
325 | |
326 | int packlen; /* total length of packet */ |
327 | int minpacket; /* min ip packet size */ |
328 | int maxpacket; // 32 * 1024; /* max ip packet size */ |
329 | int pmtu; /* Path MTU Discovery (RFC1191) */ |
330 | |
331 | char *hostname; |
332 | |
333 | uint16_t ident; |
334 | uint16_t port; // 32768 + 666; /* start udp dest port # for probe packets */ |
335 | |
336 | int waittime; // 5; /* time to wait for response (in seconds) */ |
337 | int doipcksum; // 1; /* calculate ip checksums by default */ |
338 | |
339 | #if ENABLE_FEATURE_TRACEROUTE_SOURCE_ROUTE |
340 | int optlen; /* length of ip options */ |
341 | #else |
342 | #define optlen 0 |
343 | #endif |
344 | |
345 | struct sockaddr_storage whereto; /* Who to try to reach */ |
346 | struct sockaddr_storage wherefrom; /* Who we are */ |
347 | /* last inbound (icmp) packet */ |
348 | unsigned char packet[512]; |
349 | #if ENABLE_FEATURE_TRACEROUTE_SOURCE_ROUTE |
350 | /* Maximum number of gateways (include room for one noop) */ |
351 | #define NGATEWAYS ((int)((MAX_IPOPTLEN - IPOPT_MINOFF - 1) / sizeof(uint32_t))) |
352 | /* loose source route gateway list (including room for final destination) */ |
353 | uint32_t gwlist[NGATEWAYS + 1]; |
354 | #endif |
355 | }; |
356 | |
357 | #define G (*ptr_to_globals) |
358 | #define outip (G.outip ) |
359 | #define outudp (G.outudp ) |
360 | #define outdata (G.outdata ) |
361 | #define outicmp (G.outicmp ) |
362 | #define rcvsock (G.rcvsock ) |
363 | #define sndsock (G.sndsock ) |
364 | #define packlen (G.packlen ) |
365 | #define minpacket (G.minpacket) |
366 | #define maxpacket (G.maxpacket) |
367 | #define pmtu (G.pmtu ) |
368 | #define hostname (G.hostname ) |
369 | #define ident (G.ident ) |
370 | #define port (G.port ) |
371 | #define waittime (G.waittime ) |
372 | #define doipcksum (G.doipcksum) |
373 | #if ENABLE_FEATURE_TRACEROUTE_SOURCE_ROUTE |
374 | #define optlen (G.optlen ) |
375 | #endif |
376 | #define packet (G.packet ) |
377 | #define whereto (G.whereto ) |
378 | #define wherefrom (G.wherefrom) |
379 | #define gwlist (G.gwlist ) |
380 | #define INIT_G() do { \ |
381 | SET_PTR_TO_GLOBALS(xzalloc(sizeof(G))); \ |
382 | maxpacket = 32 * 1024; \ |
383 | port = 32768 + 666; \ |
384 | waittime = 5; \ |
385 | doipcksum = 1; \ |
386 | } while (0) |
387 | |
388 | |
389 | /* |
390 | * Return the interface list |
391 | */ |
392 | static int |
393 | ifaddrlist(struct IFADDRLIST **ipaddrp) |
394 | { |
395 | enum { IFREQ_BUFSIZE = (32 * 1024) / sizeof(struct ifreq) }; |
396 | |
397 | int fd, nipaddr; |
398 | #ifdef HAVE_SOCKADDR_SA_LEN |
399 | int n; |
400 | #endif |
401 | struct ifreq *ifrp, *ifend, *ifnext; |
402 | struct sockaddr_in *addr_sin; |
403 | struct IFADDRLIST *al; |
404 | struct ifconf ifc; |
405 | struct ifreq ifr; |
406 | /* Was on stack, but 32k is a bit too much: */ |
407 | struct ifreq *ibuf = xmalloc(IFREQ_BUFSIZE * sizeof(ibuf[0])); |
408 | struct IFADDRLIST *st_ifaddrlist; |
409 | |
410 | fd = xsocket(AF_INET, SOCK_DGRAM, 0); |
411 | |
412 | ifc.ifc_len = IFREQ_BUFSIZE * sizeof(ibuf[0]); |
413 | ifc.ifc_buf = (caddr_t)ibuf; |
414 | |
415 | if (ioctl(fd, SIOCGIFCONF, (char *)&ifc) < 0 |
416 | || ifc.ifc_len < (int)sizeof(struct ifreq) |
417 | ) { |
418 | if (errno == EINVAL) |
419 | bb_error_msg_and_die( |
420 | "SIOCGIFCONF: ifreq struct too small (%u bytes)", |
421 | (unsigned)(IFREQ_BUFSIZE * sizeof(ibuf[0]))); |
422 | bb_perror_msg_and_die("SIOCGIFCONF"); |
423 | } |
424 | ifrp = ibuf; |
425 | ifend = (struct ifreq *)((char *)ibuf + ifc.ifc_len); |
426 | |
427 | nipaddr = 1 + (ifc.ifc_len / sizeof(struct ifreq)); |
428 | st_ifaddrlist = xzalloc(nipaddr * sizeof(struct IFADDRLIST)); |
429 | al = st_ifaddrlist; |
430 | nipaddr = 0; |
431 | |
432 | for (; ifrp < ifend; ifrp = ifnext) { |
433 | #ifdef HAVE_SOCKADDR_SA_LEN |
434 | n = ifrp->ifr_addr.sa_len + sizeof(ifrp->ifr_name); |
435 | if (n < sizeof(*ifrp)) |
436 | ifnext = ifrp + 1; |
437 | else |
438 | ifnext = (struct ifreq *)((char *)ifrp + n); |
439 | if (ifrp->ifr_addr.sa_family != AF_INET) |
440 | continue; |
441 | #else |
442 | ifnext = ifrp + 1; |
443 | #endif |
444 | /* |
445 | * Need a template to preserve address info that is |
446 | * used below to locate the next entry. (Otherwise, |
447 | * SIOCGIFFLAGS stomps over it because the requests |
448 | * are returned in a union.) |
449 | */ |
450 | strncpy(ifr.ifr_name, ifrp->ifr_name, sizeof(ifr.ifr_name)); |
451 | if (ioctl(fd, SIOCGIFFLAGS, (char *)&ifr) < 0) { |
452 | if (errno == ENXIO) |
453 | continue; |
454 | bb_perror_msg_and_die("SIOCGIFFLAGS: %.*s", |
455 | (int)sizeof(ifr.ifr_name), ifr.ifr_name); |
456 | } |
457 | |
458 | /* Must be up */ |
459 | if ((ifr.ifr_flags & IFF_UP) == 0) |
460 | continue; |
461 | |
462 | safe_strncpy(al->device, ifr.ifr_name, sizeof(ifr.ifr_name) + 1); |
463 | #ifdef sun |
464 | /* Ignore sun virtual interfaces */ |
465 | if (strchr(al->device, ':') != NULL) |
466 | continue; |
467 | #endif |
468 | ioctl_or_perror_and_die(fd, SIOCGIFADDR, (char *)&ifr, |
469 | "SIOCGIFADDR: %s", al->device); |
470 | |
471 | addr_sin = (struct sockaddr_in *)&ifr.ifr_addr; |
472 | al->addr = addr_sin->sin_addr.s_addr; |
473 | ++al; |
474 | ++nipaddr; |
475 | } |
476 | if (nipaddr == 0) |
477 | bb_error_msg_and_die("can't find any network interfaces"); |
478 | |
479 | free(ibuf); |
480 | close(fd); |
481 | *ipaddrp = st_ifaddrlist; |
482 | return nipaddr; |
483 | } |
484 | |
485 | |
486 | static void |
487 | setsin(struct sockaddr_in *addr_sin, uint32_t addr) |
488 | { |
489 | memset(addr_sin, 0, sizeof(*addr_sin)); |
490 | #ifdef HAVE_SOCKADDR_SA_LEN |
491 | addr_sin->sin_len = sizeof(*addr_sin); |
492 | #endif |
493 | addr_sin->sin_family = AF_INET; |
494 | addr_sin->sin_addr.s_addr = addr; |
495 | } |
496 | |
497 | |
498 | /* |
499 | * Return the source address for the given destination address |
500 | */ |
501 | static void |
502 | findsaddr(const struct sockaddr_in *to, struct sockaddr_in *from) |
503 | { |
504 | int i, n; |
505 | FILE *f; |
506 | uint32_t mask; |
507 | uint32_t dest, tmask; |
508 | struct IFADDRLIST *al; |
509 | char buf[256], tdevice[256], device[256]; |
510 | |
511 | f = xfopen_for_read("/proc/net/route"); |
512 | |
513 | /* Find the appropriate interface */ |
514 | n = 0; |
515 | mask = 0; |
516 | device[0] = '\0'; |
517 | while (fgets(buf, sizeof(buf), f) != NULL) { |
518 | ++n; |
519 | if (n == 1 && strncmp(buf, "Iface", 5) == 0) |
520 | continue; |
521 | i = sscanf(buf, "%255s %x %*s %*s %*s %*s %*s %x", |
522 | tdevice, &dest, &tmask); |
523 | if (i != 3) |
524 | bb_error_msg_and_die("junk in buffer"); |
525 | if ((to->sin_addr.s_addr & tmask) == dest |
526 | && (tmask > mask || mask == 0) |
527 | ) { |
528 | mask = tmask; |
529 | strcpy(device, tdevice); |
530 | } |
531 | } |
532 | fclose(f); |
533 | |
534 | if (device[0] == '\0') |
535 | bb_error_msg_and_die("can't find interface"); |
536 | |
537 | /* Get the interface address list */ |
538 | n = ifaddrlist(&al); |
539 | |
540 | /* Find our appropriate source address */ |
541 | for (i = n; i > 0; --i, ++al) |
542 | if (strcmp(device, al->device) == 0) |
543 | break; |
544 | if (i <= 0) |
545 | bb_error_msg_and_die("can't find interface %s", device); |
546 | |
547 | setsin(from, al->addr); |
548 | } |
549 | |
550 | /* |
551 | "Usage: %s [-dFIlnrvx] [-g gateway] [-i iface] [-f first_ttl]\n" |
552 | "\t[-m max_ttl] [ -p port] [-q nqueries] [-s src_addr] [-t tos]\n" |
553 | "\t[-w waittime] [-z pausemsecs] host [packetlen]" |
554 | |
555 | */ |
556 | |
557 | static int |
558 | wait_for_reply(int sock, struct sockaddr_in *fromp) |
559 | { |
560 | struct pollfd pfd[1]; |
561 | int cc = 0; |
562 | socklen_t fromlen = sizeof(*fromp); |
563 | |
564 | pfd[0].fd = sock; |
565 | pfd[0].events = POLLIN; |
566 | if (safe_poll(pfd, 1, waittime * 1000) > 0) |
567 | cc = recvfrom(sock, packet, sizeof(packet), 0, |
568 | (struct sockaddr *)fromp, &fromlen); |
569 | return cc; |
570 | } |
571 | |
572 | /* |
573 | * Checksum routine for Internet Protocol family headers (C Version) |
574 | */ |
575 | static uint16_t |
576 | in_cksum(uint16_t *addr, int len) |
577 | { |
578 | int nleft = len; |
579 | uint16_t *w = addr; |
580 | uint16_t answer; |
581 | int sum = 0; |
582 | |
583 | /* |
584 | * Our algorithm is simple, using a 32 bit accumulator (sum), |
585 | * we add sequential 16 bit words to it, and at the end, fold |
586 | * back all the carry bits from the top 16 bits into the lower |
587 | * 16 bits. |
588 | */ |
589 | while (nleft > 1) { |
590 | sum += *w++; |
591 | nleft -= 2; |
592 | } |
593 | |
594 | /* mop up an odd byte, if necessary */ |
595 | if (nleft == 1) |
596 | sum += *(unsigned char *)w; |
597 | |
598 | /* |
599 | * add back carry outs from top 16 bits to low 16 bits |
600 | */ |
601 | sum = (sum >> 16) + (sum & 0xffff); /* add hi 16 to low 16 */ |
602 | sum += (sum >> 16); /* add carry */ |
603 | answer = ~sum; /* truncate to 16 bits */ |
604 | return answer; |
605 | } |
606 | |
607 | |
608 | static void |
609 | send_probe(int seq, int ttl) |
610 | { |
611 | int cc; |
612 | struct udpiphdr *ui, *oui; |
613 | struct ip tip; |
614 | |
615 | outip->ip_ttl = ttl; |
616 | outip->ip_id = htons(ident + seq); |
617 | |
618 | /* |
619 | * In most cases, the kernel will recalculate the ip checksum. |
620 | * But we must do it anyway so that the udp checksum comes out |
621 | * right. |
622 | */ |
623 | if (doipcksum) { |
624 | outip->ip_sum = |
625 | in_cksum((uint16_t *)outip, sizeof(*outip) + optlen); |
626 | if (outip->ip_sum == 0) |
627 | outip->ip_sum = 0xffff; |
628 | } |
629 | |
630 | /* Payload */ |
631 | outdata->seq = seq; |
632 | outdata->ttl = ttl; |
633 | // UNUSED: was storing gettimeofday's result there, but never ever checked it |
634 | /*memcpy(&outdata->tv, tp, sizeof(outdata->tv));*/ |
635 | |
636 | #if ENABLE_FEATURE_TRACEROUTE_USE_ICMP |
637 | if (useicmp) |
638 | outicmp->icmp_seq = htons(seq); |
639 | else |
640 | #endif |
641 | outudp->dest = htons(port + seq); |
642 | |
643 | #if ENABLE_FEATURE_TRACEROUTE_USE_ICMP |
644 | if (useicmp) { |
645 | /* Always calculate checksum for icmp packets */ |
646 | outicmp->icmp_cksum = 0; |
647 | outicmp->icmp_cksum = in_cksum((uint16_t *)outicmp, |
648 | packlen - (sizeof(*outip) + optlen)); |
649 | if (outicmp->icmp_cksum == 0) |
650 | outicmp->icmp_cksum = 0xffff; |
651 | } else |
652 | #endif |
653 | if (doipcksum) { |
654 | /* Checksum (we must save and restore ip header) */ |
655 | tip = *outip; |
656 | ui = (struct udpiphdr *)outip; |
657 | oui = (struct udpiphdr *)&tip; |
658 | /* Easier to zero and put back things that are ok */ |
659 | memset((char *)ui, 0, sizeof(ui->ui_i)); |
660 | ui->ui_src = oui->ui_src; |
661 | ui->ui_dst = oui->ui_dst; |
662 | ui->ui_pr = oui->ui_pr; |
663 | ui->ui_len = outudp->len; |
664 | outudp->check = 0; |
665 | outudp->check = in_cksum((uint16_t *)ui, packlen); |
666 | if (outudp->check == 0) |
667 | outudp->check = 0xffff; |
668 | *outip = tip; |
669 | } |
670 | |
671 | #if ENABLE_FEATURE_TRACEROUTE_VERBOSE |
672 | /* XXX undocumented debugging hack */ |
673 | if (verbose > 1) { |
674 | const uint16_t *sp; |
675 | int nshorts, i; |
676 | |
677 | sp = (uint16_t *)outip; |
678 | nshorts = (unsigned)packlen / sizeof(uint16_t); |
679 | i = 0; |
680 | printf("[ %d bytes", packlen); |
681 | while (--nshorts >= 0) { |
682 | if ((i++ % 8) == 0) |
683 | printf("\n\t"); |
684 | printf(" %04x", ntohs(*sp)); |
685 | sp++; |
686 | } |
687 | if (packlen & 1) { |
688 | if ((i % 8) == 0) |
689 | printf("\n\t"); |
690 | printf(" %02x", *(unsigned char *)sp); |
691 | } |
692 | printf("]\n"); |
693 | } |
694 | #endif |
695 | |
696 | #if !defined(IP_HDRINCL) && defined(IP_TTL) |
697 | if (setsockopt(sndsock, IPPROTO_IP, IP_TTL, |
698 | (char *)&ttl, sizeof(ttl)) < 0) { |
699 | bb_perror_msg_and_die("setsockopt ttl %d", ttl); |
700 | } |
701 | #endif |
702 | |
703 | cc = xsendto(sndsock, (char *)outip, |
704 | packlen, (struct sockaddr *)&whereto, sizeof(whereto)); |
705 | if (cc != packlen) { |
706 | bb_info_msg("wrote %s %d chars, ret=%d", hostname, packlen, cc); |
707 | } |
708 | } |
709 | |
710 | #if ENABLE_FEATURE_TRACEROUTE_VERBOSE |
711 | /* |
712 | * Convert an ICMP "type" field to a printable string. |
713 | */ |
714 | static inline const char * |
715 | pr_type(unsigned char t) |
716 | { |
717 | static const char *const ttab[] = { |
718 | "Echo Reply", "ICMP 1", "ICMP 2", "Dest Unreachable", |
719 | "Source Quench", "Redirect", "ICMP 6", "ICMP 7", |
720 | "Echo", "Router Advert", "Router Solicit", "Time Exceeded", |
721 | "Param Problem", "Timestamp", "Timestamp Reply", "Info Request", |
722 | "Info Reply", "Mask Request", "Mask Reply" |
723 | }; |
724 | |
725 | if (t > 18) |
726 | return "OUT-OF-RANGE"; |
727 | |
728 | return ttab[t]; |
729 | } |
730 | #endif |
731 | |
732 | #if !ENABLE_FEATURE_TRACEROUTE_VERBOSE |
733 | #define packet_ok(buf, cc, from, seq) \ |
734 | packet_ok(buf, cc, seq) |
735 | #endif |
736 | static int |
737 | packet_ok(unsigned char *buf, int cc, struct sockaddr_in *from, int seq) |
738 | { |
739 | struct icmp *icp; |
740 | unsigned char type, code; |
741 | int hlen; |
742 | struct ip *ip; |
743 | |
744 | ip = (struct ip *) buf; |
745 | hlen = ip->ip_hl << 2; |
746 | if (cc < hlen + ICMP_MINLEN) { |
747 | #if ENABLE_FEATURE_TRACEROUTE_VERBOSE |
748 | if (verbose) |
749 | printf("packet too short (%d bytes) from %s\n", cc, |
750 | inet_ntoa(from->sin_addr)); |
751 | #endif |
752 | return 0; |
753 | } |
754 | cc -= hlen; |
755 | icp = (struct icmp *)(buf + hlen); |
756 | type = icp->icmp_type; |
757 | code = icp->icmp_code; |
758 | /* Path MTU Discovery (RFC1191) */ |
759 | if (code != ICMP_UNREACH_NEEDFRAG) |
760 | pmtu = 0; |
761 | else { |
762 | pmtu = ntohs(icp->icmp_nextmtu); |
763 | } |
764 | if ((type == ICMP_TIMXCEED && code == ICMP_TIMXCEED_INTRANS) || |
765 | type == ICMP_UNREACH || type == ICMP_ECHOREPLY) { |
766 | struct ip *hip; |
767 | struct udphdr *up; |
768 | |
769 | hip = &icp->icmp_ip; |
770 | hlen = hip->ip_hl << 2; |
771 | #if ENABLE_FEATURE_TRACEROUTE_USE_ICMP |
772 | if (useicmp) { |
773 | struct icmp *hicmp; |
774 | |
775 | /* XXX */ |
776 | if (type == ICMP_ECHOREPLY && |
777 | icp->icmp_id == htons(ident) && |
778 | icp->icmp_seq == htons(seq)) |
779 | return -2; |
780 | |
781 | hicmp = (struct icmp *)((unsigned char *)hip + hlen); |
782 | /* XXX 8 is a magic number */ |
783 | if (hlen + 8 <= cc && |
784 | hip->ip_p == IPPROTO_ICMP && |
785 | hicmp->icmp_id == htons(ident) && |
786 | hicmp->icmp_seq == htons(seq)) |
787 | return (type == ICMP_TIMXCEED ? -1 : code + 1); |
788 | } else |
789 | #endif |
790 | { |
791 | up = (struct udphdr *)((unsigned char *)hip + hlen); |
792 | /* XXX 8 is a magic number */ |
793 | if (hlen + 12 <= cc && |
794 | hip->ip_p == IPPROTO_UDP && |
795 | up->source == htons(ident) && |
796 | up->dest == htons(port + seq)) |
797 | return (type == ICMP_TIMXCEED ? -1 : code + 1); |
798 | } |
799 | } |
800 | #if ENABLE_FEATURE_TRACEROUTE_VERBOSE |
801 | if (verbose) { |
802 | int i; |
803 | uint32_t *lp = (uint32_t *)&icp->icmp_ip; |
804 | |
805 | printf("\n%d bytes from %s to " |
806 | "%s: icmp type %d (%s) code %d\n", |
807 | cc, inet_ntoa(from->sin_addr), |
808 | inet_ntoa(ip->ip_dst), type, pr_type(type), icp->icmp_code); |
809 | for (i = 4; i < cc; i += sizeof(*lp)) |
810 | printf("%2d: x%8.8x\n", i, *lp++); |
811 | } |
812 | #endif |
813 | return 0; |
814 | } |
815 | |
816 | |
817 | /* |
818 | * Construct an Internet address representation. |
819 | * If the nflag has been supplied, give |
820 | * numeric value, otherwise try for symbolic name. |
821 | */ |
822 | static void |
823 | print_inetname(struct sockaddr_in *from) |
824 | { |
825 | const char *ina; |
826 | |
827 | ina = inet_ntoa(from->sin_addr); |
828 | if (nflag) |
829 | printf(" %s", ina); |
830 | else { |
831 | char *n = NULL; |
832 | if (from->sin_addr.s_addr != INADDR_ANY) |
833 | n = xmalloc_sockaddr2host_noport((struct sockaddr*)from); |
834 | printf(" %s (%s)", (n ? n : ina), ina); |
835 | free(n); |
836 | } |
837 | } |
838 | |
839 | static void |
840 | print(unsigned char *buf, int cc, struct sockaddr_in *from) |
841 | { |
842 | struct ip *ip; |
843 | int hlen; |
844 | |
845 | ip = (struct ip *) buf; |
846 | hlen = ip->ip_hl << 2; |
847 | cc -= hlen; |
848 | |
849 | print_inetname(from); |
850 | #if ENABLE_FEATURE_TRACEROUTE_VERBOSE |
851 | if (verbose) |
852 | printf(" %d bytes to %s", cc, inet_ntoa(ip->ip_dst)); |
853 | #endif |
854 | } |
855 | |
856 | |
857 | static struct hostinfo * |
858 | gethostinfo(const char *host) |
859 | { |
860 | int n; |
861 | struct hostent *hp; |
862 | struct hostinfo *hi; |
863 | char **p; |
864 | uint32_t addr, *ap; |
865 | |
866 | hi = xzalloc(sizeof(*hi)); |
867 | addr = inet_addr(host); |
868 | if (addr != 0xffffffff) { |
869 | hi->name = xstrdup(host); |
870 | hi->n = 1; |
871 | hi->addrs = xzalloc(sizeof(hi->addrs[0])); |
872 | hi->addrs[0] = addr; |
873 | return hi; |
874 | } |
875 | |
876 | hp = xgethostbyname(host); |
877 | if (hp->h_addrtype != AF_INET || hp->h_length != 4) |
878 | bb_perror_msg_and_die("bad host %s", host); |
879 | hi->name = xstrdup(hp->h_name); |
880 | for (n = 0, p = hp->h_addr_list; *p != NULL; ++n, ++p) |
881 | continue; |
882 | hi->n = n; |
883 | hi->addrs = xzalloc(n * sizeof(hi->addrs[0])); |
884 | for (ap = hi->addrs, p = hp->h_addr_list; *p != NULL; ++ap, ++p) |
885 | memcpy(ap, *p, sizeof(*ap)); |
886 | return hi; |
887 | } |
888 | |
889 | static void |
890 | freehostinfo(struct hostinfo *hi) |
891 | { |
892 | free(hi->name); |
893 | free(hi->addrs); |
894 | free(hi); |
895 | } |
896 | |
897 | #if ENABLE_FEATURE_TRACEROUTE_SOURCE_ROUTE |
898 | static void |
899 | getaddr(uint32_t *ap, const char *host) |
900 | { |
901 | struct hostinfo *hi; |
902 | |
903 | hi = gethostinfo(host); |
904 | *ap = hi->addrs[0]; |
905 | freehostinfo(hi); |
906 | } |
907 | #endif |
908 | |
909 | static void |
910 | print_delta_ms(unsigned t1p, unsigned t2p) |
911 | { |
912 | unsigned tt = t2p - t1p; |
913 | printf(" %u.%03u ms", tt/1000, tt%1000); |
914 | } |
915 | |
916 | int traceroute_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; |
917 | int traceroute_main(int argc, char **argv) |
918 | { |
919 | int code, n; |
920 | unsigned char *outp; |
921 | uint32_t *ap; |
922 | struct sockaddr_in *from; |
923 | struct sockaddr_in *to; |
924 | struct hostinfo *hi; |
925 | int ttl, probe, i; |
926 | int seq = 0; |
927 | int tos = 0; |
928 | char *tos_str; |
929 | char *source; |
930 | unsigned op; |
931 | #if ENABLE_FEATURE_TRACEROUTE_SOURCE_ROUTE |
932 | int lsrr = 0; |
933 | #endif |
934 | uint16_t off = 0; |
935 | struct IFADDRLIST *al; |
936 | char *device; |
937 | int max_ttl = 30; |
938 | char *max_ttl_str; |
939 | char *port_str; |
940 | int nprobes = 3; |
941 | char *nprobes_str; |
942 | char *waittime_str; |
943 | unsigned pausemsecs = 0; |
944 | char *pausemsecs_str; |
945 | int first_ttl = 1; |
946 | char *first_ttl_str; |
947 | #if ENABLE_FEATURE_TRACEROUTE_SOURCE_ROUTE |
948 | llist_t *source_route_list = NULL; |
949 | #endif |
950 | |
951 | INIT_G(); |
952 | from = (struct sockaddr_in *)&wherefrom; |
953 | to = (struct sockaddr_in *)&whereto; |
954 | |
955 | //opterr = 0; |
956 | #if ENABLE_FEATURE_TRACEROUTE_SOURCE_ROUTE |
957 | opt_complementary = "x-x:g::"; |
958 | #else |
959 | opt_complementary = "x-x"; |
960 | #endif |
961 | |
962 | op = getopt32(argv, "FIlnrdvxt:i:m:p:q:s:w:z:f:" |
963 | #if ENABLE_FEATURE_TRACEROUTE_SOURCE_ROUTE |
964 | "g:" |
965 | #endif |
966 | , &tos_str, &device, &max_ttl_str, &port_str, &nprobes_str |
967 | , &source, &waittime_str, &pausemsecs_str, &first_ttl_str |
968 | #if ENABLE_FEATURE_TRACEROUTE_SOURCE_ROUTE |
969 | , &source_route_list |
970 | #endif |
971 | ); |
972 | |
973 | if (op & OPT_DONT_FRAGMNT) |
974 | off = IP_DF; |
975 | if (op & OPT_IP_CHKSUM) { |
976 | doipcksum = 0; |
977 | bb_error_msg("warning: ip checksums disabled"); |
978 | } |
979 | if (op & OPT_TOS) |
980 | tos = xatou_range(tos_str, 0, 255); |
981 | if (op & OPT_MAX_TTL) |
982 | max_ttl = xatou_range(max_ttl_str, 1, 255); |
983 | if (op & OPT_PORT) |
984 | port = xatou16(port_str); |
985 | if (op & OPT_NPROBES) |
986 | nprobes = xatou_range(nprobes_str, 1, INT_MAX); |
987 | if (op & OPT_SOURCE) { |
988 | /* |
989 | * set the ip source address of the outbound |
990 | * probe (e.g., on a multi-homed host). |
991 | */ |
992 | if (getuid()) |
993 | bb_error_msg_and_die("-s %s: permission denied", source); |
994 | } |
995 | if (op & OPT_WAITTIME) |
996 | waittime = xatou_range(waittime_str, 2, 24 * 60 * 60); |
997 | if (op & OPT_PAUSE_MS) |
998 | pausemsecs = xatou_range(pausemsecs_str, 0, 60 * 60 * 1000); |
999 | if (op & OPT_FIRST_TTL) |
1000 | first_ttl = xatou_range(first_ttl_str, 1, 255); |
1001 | |
1002 | #if ENABLE_FEATURE_TRACEROUTE_SOURCE_ROUTE |
1003 | if (source_route_list) { |
1004 | while (source_route_list) { |
1005 | if (lsrr >= NGATEWAYS) |
1006 | bb_error_msg_and_die("no more than %d gateways", NGATEWAYS); |
1007 | getaddr(gwlist + lsrr, llist_pop(&source_route_list)); |
1008 | ++lsrr; |
1009 | } |
1010 | optlen = (lsrr + 1) * sizeof(gwlist[0]); |
1011 | } |
1012 | #endif |
1013 | |
1014 | if (first_ttl > max_ttl) { |
1015 | bb_error_msg_and_die( |
1016 | "first ttl (%d) may not be greater than max ttl (%d)", |
1017 | first_ttl, max_ttl); |
1018 | } |
1019 | |
1020 | minpacket = sizeof(*outip) + sizeof(*outdata) + optlen; |
1021 | |
1022 | #if ENABLE_FEATURE_TRACEROUTE_USE_ICMP |
1023 | if (useicmp) |
1024 | minpacket += 8; /* XXX magic number */ |
1025 | else |
1026 | #endif |
1027 | minpacket += sizeof(*outudp); |
1028 | packlen = minpacket; /* minimum sized packet */ |
1029 | |
1030 | /* Process destination and optional packet size */ |
1031 | switch (argc - optind) { |
1032 | |
1033 | case 2: |
1034 | packlen = xatoul_range(argv[optind + 1], minpacket, maxpacket); |
1035 | /* Fall through */ |
1036 | |
1037 | case 1: |
1038 | hostname = argv[optind]; |
1039 | hi = gethostinfo(hostname); |
1040 | setsin(to, hi->addrs[0]); |
1041 | if (hi->n > 1) |
1042 | bb_error_msg("warning: %s has multiple addresses; using %s", |
1043 | hostname, inet_ntoa(to->sin_addr)); |
1044 | hostname = hi->name; |
1045 | hi->name = NULL; |
1046 | freehostinfo(hi); |
1047 | break; |
1048 | |
1049 | default: |
1050 | bb_show_usage(); |
1051 | } |
1052 | |
1053 | /* Ensure the socket fds won't be 0, 1 or 2 */ |
1054 | bb_sanitize_stdio(); |
1055 | |
1056 | rcvsock = xsocket(AF_INET, SOCK_RAW, IPPROTO_ICMP); |
1057 | |
1058 | #if TRACEROUTE_SO_DEBUG |
1059 | if (op & OPT_DEBUG) |
1060 | setsockopt(rcvsock, SOL_SOCKET, SO_DEBUG, |
1061 | &const_int_1, sizeof(const_int_1)); |
1062 | #endif |
1063 | if (op & OPT_BYPASS_ROUTE) |
1064 | setsockopt(rcvsock, SOL_SOCKET, SO_DONTROUTE, |
1065 | &const_int_1, sizeof(const_int_1)); |
1066 | |
1067 | sndsock = xsocket(AF_INET, SOCK_RAW, IPPROTO_RAW); |
1068 | |
1069 | #if ENABLE_FEATURE_TRACEROUTE_SOURCE_ROUTE |
1070 | #if defined(IP_OPTIONS) |
1071 | if (lsrr > 0) { |
1072 | unsigned char optlist[MAX_IPOPTLEN]; |
1073 | |
1074 | /* final hop */ |
1075 | gwlist[lsrr] = to->sin_addr.s_addr; |
1076 | ++lsrr; |
1077 | |
1078 | /* force 4 byte alignment */ |
1079 | optlist[0] = IPOPT_NOP; |
1080 | /* loose source route option */ |
1081 | optlist[1] = IPOPT_LSRR; |
1082 | i = lsrr * sizeof(gwlist[0]); |
1083 | optlist[2] = i + 3; |
1084 | /* Pointer to LSRR addresses */ |
1085 | optlist[3] = IPOPT_MINOFF; |
1086 | memcpy(optlist + 4, gwlist, i); |
1087 | |
1088 | if ((setsockopt(sndsock, IPPROTO_IP, IP_OPTIONS, |
1089 | (char *)optlist, i + sizeof(gwlist[0]))) < 0) { |
1090 | bb_perror_msg_and_die("IP_OPTIONS"); |
1091 | } |
1092 | } |
1093 | #endif /* IP_OPTIONS */ |
1094 | #endif /* CONFIG_FEATURE_TRACEROUTE_SOURCE_ROUTE */ |
1095 | |
1096 | #ifdef SO_SNDBUF |
1097 | if (setsockopt(sndsock, SOL_SOCKET, SO_SNDBUF, &packlen, sizeof(packlen)) < 0) { |
1098 | bb_perror_msg_and_die("SO_SNDBUF"); |
1099 | } |
1100 | #endif |
1101 | #ifdef IP_HDRINCL |
1102 | if (setsockopt(sndsock, IPPROTO_IP, IP_HDRINCL, &const_int_1, sizeof(const_int_1)) < 0 |
1103 | && errno != ENOPROTOOPT |
1104 | ) { |
1105 | bb_perror_msg_and_die("IP_HDRINCL"); |
1106 | } |
1107 | #else |
1108 | #ifdef IP_TOS |
1109 | if (tos_str && setsockopt(sndsock, IPPROTO_IP, IP_TOS, &tos, sizeof(tos)) < 0) { |
1110 | bb_perror_msg_and_die("setsockopt tos %d", tos); |
1111 | } |
1112 | #endif |
1113 | #endif |
1114 | #if TRACEROUTE_SO_DEBUG |
1115 | if (op & OPT_DEBUG) |
1116 | setsockopt(sndsock, SOL_SOCKET, SO_DEBUG, |
1117 | &const_int_1, sizeof(const_int_1)); |
1118 | #endif |
1119 | if (op & OPT_BYPASS_ROUTE) |
1120 | setsockopt(sndsock, SOL_SOCKET, SO_DONTROUTE, |
1121 | &const_int_1, sizeof(const_int_1)); |
1122 | |
1123 | /* Revert to non-privileged user after opening sockets */ |
1124 | xsetgid(getgid()); |
1125 | xsetuid(getuid()); |
1126 | |
1127 | outip = xzalloc(packlen); |
1128 | |
1129 | outip->ip_v = IPVERSION; |
1130 | if (tos_str) |
1131 | outip->ip_tos = tos; |
1132 | outip->ip_len = htons(packlen); |
1133 | outip->ip_off = htons(off); |
1134 | outp = (unsigned char *)(outip + 1); |
1135 | outip->ip_dst = to->sin_addr; |
1136 | |
1137 | outip->ip_hl = (outp - (unsigned char *)outip) >> 2; |
1138 | ident = (getpid() & 0xffff) | 0x8000; |
1139 | #if ENABLE_FEATURE_TRACEROUTE_USE_ICMP |
1140 | if (useicmp) { |
1141 | outip->ip_p = IPPROTO_ICMP; |
1142 | outicmp = (struct icmp *)outp; |
1143 | outicmp->icmp_type = ICMP_ECHO; |
1144 | outicmp->icmp_id = htons(ident); |
1145 | outdata = (outdata_t *)(outp + 8); /* XXX magic number */ |
1146 | } else |
1147 | #endif |
1148 | { |
1149 | outip->ip_p = IPPROTO_UDP; |
1150 | outudp = (struct udphdr *)outp; |
1151 | outudp->source = htons(ident); |
1152 | outudp->len = htons((uint16_t)(packlen - (sizeof(*outip) + optlen))); |
1153 | outdata = (outdata_t *)(outudp + 1); |
1154 | } |
1155 | |
1156 | /* Get the interface address list */ |
1157 | n = ifaddrlist(&al); |
1158 | |
1159 | /* Look for a specific device */ |
1160 | if (op & OPT_DEVICE) { |
1161 | for (i = n; i > 0; --i, ++al) |
1162 | if (strcmp(device, al->device) == 0) |
1163 | goto found_dev; |
1164 | bb_error_msg_and_die("can't find interface %s", device); |
1165 | } |
1166 | found_dev: |
1167 | |
1168 | /* Determine our source address */ |
1169 | if (!(op & OPT_SOURCE)) { |
1170 | /* |
1171 | * If a device was specified, use the interface address. |
1172 | * Otherwise, try to determine our source address. |
1173 | */ |
1174 | if (op & OPT_DEVICE) |
1175 | setsin(from, al->addr); |
1176 | findsaddr(to, from); |
1177 | } else { |
1178 | hi = gethostinfo(source); |
1179 | source = hi->name; |
1180 | hi->name = NULL; |
1181 | /* |
1182 | * If the device was specified make sure it |
1183 | * corresponds to the source address specified. |
1184 | * Otherwise, use the first address (and warn if |
1185 | * there are more than one). |
1186 | */ |
1187 | if (op & OPT_DEVICE) { |
1188 | for (i = hi->n, ap = hi->addrs; i > 0; --i, ++ap) |
1189 | if (*ap == al->addr) |
1190 | goto found_dev2; |
1191 | bb_error_msg_and_die("%s is not on interface %s", |
1192 | source, device); |
1193 | found_dev2: |
1194 | setsin(from, *ap); |
1195 | } else { |
1196 | setsin(from, hi->addrs[0]); |
1197 | if (hi->n > 1) |
1198 | bb_error_msg( |
1199 | "warning: %s has multiple addresses; using %s", |
1200 | source, inet_ntoa(from->sin_addr)); |
1201 | } |
1202 | freehostinfo(hi); |
1203 | } |
1204 | |
1205 | outip->ip_src = from->sin_addr; |
1206 | #ifndef IP_HDRINCL |
1207 | xbind(sndsock, (struct sockaddr *)from, sizeof(*from)); |
1208 | #endif |
1209 | |
1210 | printf("traceroute to %s (%s)", hostname, inet_ntoa(to->sin_addr)); |
1211 | if (op & OPT_SOURCE) |
1212 | printf(" from %s", source); |
1213 | printf(", %d hops max, %d byte packets\n", max_ttl, packlen); |
1214 | fflush(stdout); |
1215 | |
1216 | for (ttl = first_ttl; ttl <= max_ttl; ++ttl) { |
1217 | uint32_t lastaddr = 0; |
1218 | int gotlastaddr = 0; |
1219 | int got_there = 0; |
1220 | int unreachable = 0; |
1221 | int sentfirst = 0; |
1222 | |
1223 | printf("%2d ", ttl); |
1224 | for (probe = 0; probe < nprobes; ++probe) { |
1225 | int cc; |
1226 | unsigned t1; |
1227 | unsigned t2; |
1228 | struct ip *ip; |
1229 | |
1230 | if (sentfirst && pausemsecs > 0) |
1231 | usleep(pausemsecs * 1000); |
1232 | t1 = monotonic_us(); |
1233 | send_probe(++seq, ttl); |
1234 | ++sentfirst; |
1235 | while ((cc = wait_for_reply(rcvsock, from)) != 0) { |
1236 | t2 = monotonic_us(); |
1237 | i = packet_ok(packet, cc, from, seq); |
1238 | /* Skip short packet */ |
1239 | if (i == 0) |
1240 | continue; |
1241 | if (!gotlastaddr || |
1242 | from->sin_addr.s_addr != lastaddr) { |
1243 | print(packet, cc, from); |
1244 | lastaddr = from->sin_addr.s_addr; |
1245 | ++gotlastaddr; |
1246 | } |
1247 | print_delta_ms(t1, t2); |
1248 | ip = (struct ip *)packet; |
1249 | if (op & OPT_TTL_FLAG) |
1250 | printf(" (%d)", ip->ip_ttl); |
1251 | if (i == -2) { |
1252 | if (ip->ip_ttl <= 1) |
1253 | printf(" !"); |
1254 | ++got_there; |
1255 | break; |
1256 | } |
1257 | /* time exceeded in transit */ |
1258 | if (i == -1) |
1259 | break; |
1260 | code = i - 1; |
1261 | switch (code) { |
1262 | |
1263 | case ICMP_UNREACH_PORT: |
1264 | if (ip->ip_ttl <= 1) |
1265 | printf(" !"); |
1266 | ++got_there; |
1267 | break; |
1268 | |
1269 | case ICMP_UNREACH_NET: |
1270 | ++unreachable; |
1271 | printf(" !N"); |
1272 | break; |
1273 | |
1274 | case ICMP_UNREACH_HOST: |
1275 | ++unreachable; |
1276 | printf(" !H"); |
1277 | break; |
1278 | |
1279 | case ICMP_UNREACH_PROTOCOL: |
1280 | ++got_there; |
1281 | printf(" !P"); |
1282 | break; |
1283 | |
1284 | case ICMP_UNREACH_NEEDFRAG: |
1285 | ++unreachable; |
1286 | printf(" !F-%d", pmtu); |
1287 | break; |
1288 | |
1289 | case ICMP_UNREACH_SRCFAIL: |
1290 | ++unreachable; |
1291 | printf(" !S"); |
1292 | break; |
1293 | |
1294 | case ICMP_UNREACH_FILTER_PROHIB: |
1295 | case ICMP_UNREACH_NET_PROHIB: /* misuse */ |
1296 | ++unreachable; |
1297 | printf(" !A"); |
1298 | break; |
1299 | |
1300 | case ICMP_UNREACH_HOST_PROHIB: |
1301 | ++unreachable; |
1302 | printf(" !C"); |
1303 | break; |
1304 | |
1305 | case ICMP_UNREACH_HOST_PRECEDENCE: |
1306 | ++unreachable; |
1307 | printf(" !V"); |
1308 | break; |
1309 | |
1310 | case ICMP_UNREACH_PRECEDENCE_CUTOFF: |
1311 | ++unreachable; |
1312 | printf(" !C"); |
1313 | break; |
1314 | |
1315 | case ICMP_UNREACH_NET_UNKNOWN: |
1316 | case ICMP_UNREACH_HOST_UNKNOWN: |
1317 | ++unreachable; |
1318 | printf(" !U"); |
1319 | break; |
1320 | |
1321 | case ICMP_UNREACH_ISOLATED: |
1322 | ++unreachable; |
1323 | printf(" !I"); |
1324 | break; |
1325 | |
1326 | case ICMP_UNREACH_TOSNET: |
1327 | case ICMP_UNREACH_TOSHOST: |
1328 | ++unreachable; |
1329 | printf(" !T"); |
1330 | break; |
1331 | |
1332 | default: |
1333 | ++unreachable; |
1334 | printf(" !<%d>", code); |
1335 | break; |
1336 | } |
1337 | break; |
1338 | } |
1339 | if (cc == 0) |
1340 | printf(" *"); |
1341 | (void)fflush(stdout); |
1342 | } |
1343 | bb_putchar('\n'); |
1344 | if (got_there || |
1345 | (unreachable > 0 && unreachable >= nprobes - 1)) |
1346 | break; |
1347 | } |
1348 | return 0; |
1349 | } |