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rework on the ICMP MPLS extension code:
[tcpdump] / print-icmp.c
1 /*
2 * Copyright (c) 1988, 1989, 1990, 1991, 1993, 1994, 1995, 1996
3 * The Regents of the University of California. All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that: (1) source code distributions
7 * retain the above copyright notice and this paragraph in its entirety, (2)
8 * distributions including binary code include the above copyright notice and
9 * this paragraph in its entirety in the documentation or other materials
10 * provided with the distribution, and (3) all advertising materials mentioning
11 * features or use of this software display the following acknowledgement:
12 * ``This product includes software developed by the University of California,
13 * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
14 * the University nor the names of its contributors may be used to endorse
15 * or promote products derived from this software without specific prior
16 * written permission.
17 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
18 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
19 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
20 */
21
22 #ifndef lint
23 static const char rcsid[] _U_ =
24 "@(#) $Header: /tcpdump/master/tcpdump/print-icmp.c,v 1.81.2.3 2006-12-12 10:51:35 hannes Exp $ (LBL)";
25 #endif
26
27 #ifdef HAVE_CONFIG_H
28 #include "config.h"
29 #endif
30
31 #include <tcpdump-stdinc.h>
32
33 #include <stdio.h>
34 #include <string.h>
35
36 #include "interface.h"
37 #include "addrtoname.h"
38 #include "extract.h" /* must come after interface.h */
39
40 #include "ip.h"
41 #include "udp.h"
42 #include "ipproto.h"
43 #include "mpls.h"
44
45 /*
46 * Interface Control Message Protocol Definitions.
47 * Per RFC 792, September 1981.
48 */
49
50 /*
51 * Structure of an icmp header.
52 */
53 struct icmp {
54 u_int8_t icmp_type; /* type of message, see below */
55 u_int8_t icmp_code; /* type sub code */
56 u_int16_t icmp_cksum; /* ones complement cksum of struct */
57 union {
58 u_int8_t ih_pptr; /* ICMP_PARAMPROB */
59 struct in_addr ih_gwaddr; /* ICMP_REDIRECT */
60 struct ih_idseq {
61 u_int16_t icd_id;
62 u_int16_t icd_seq;
63 } ih_idseq;
64 u_int32_t ih_void;
65 } icmp_hun;
66 #define icmp_pptr icmp_hun.ih_pptr
67 #define icmp_gwaddr icmp_hun.ih_gwaddr
68 #define icmp_id icmp_hun.ih_idseq.icd_id
69 #define icmp_seq icmp_hun.ih_idseq.icd_seq
70 #define icmp_void icmp_hun.ih_void
71 union {
72 struct id_ts {
73 u_int32_t its_otime;
74 u_int32_t its_rtime;
75 u_int32_t its_ttime;
76 } id_ts;
77 struct id_ip {
78 struct ip idi_ip;
79 /* options and then 64 bits of data */
80 } id_ip;
81 u_int32_t id_mask;
82 u_int8_t id_data[1];
83 } icmp_dun;
84 #define icmp_otime icmp_dun.id_ts.its_otime
85 #define icmp_rtime icmp_dun.id_ts.its_rtime
86 #define icmp_ttime icmp_dun.id_ts.its_ttime
87 #define icmp_ip icmp_dun.id_ip.idi_ip
88 #define icmp_mask icmp_dun.id_mask
89 #define icmp_data icmp_dun.id_data
90 };
91
92 #define ICMP_MPLS_EXT_EXTRACT_VERSION(x) (((x)&0xf0)>>4)
93 #define ICMP_MPLS_EXT_VERSION 2
94
95 /*
96 * Lower bounds on packet lengths for various types.
97 * For the error advice packets must first insure that the
98 * packet is large enought to contain the returned ip header.
99 * Only then can we do the check to see if 64 bits of packet
100 * data have been returned, since we need to check the returned
101 * ip header length.
102 */
103 #define ICMP_MINLEN 8 /* abs minimum */
104 #define ICMP_EXTD_MINLEN (156 - sizeof (struct ip)) /* draft-bonica-internet-icmp-08 */
105 #define ICMP_TSLEN (8 + 3 * sizeof (u_int32_t)) /* timestamp */
106 #define ICMP_MASKLEN 12 /* address mask */
107 #define ICMP_ADVLENMIN (8 + sizeof (struct ip) + 8) /* min */
108 #define ICMP_ADVLEN(p) (8 + (IP_HL(&(p)->icmp_ip) << 2) + 8)
109 /* N.B.: must separately check that ip_hl >= 5 */
110
111 /*
112 * Definition of type and code field values.
113 */
114 #define ICMP_ECHOREPLY 0 /* echo reply */
115 #define ICMP_UNREACH 3 /* dest unreachable, codes: */
116 #define ICMP_UNREACH_NET 0 /* bad net */
117 #define ICMP_UNREACH_HOST 1 /* bad host */
118 #define ICMP_UNREACH_PROTOCOL 2 /* bad protocol */
119 #define ICMP_UNREACH_PORT 3 /* bad port */
120 #define ICMP_UNREACH_NEEDFRAG 4 /* IP_DF caused drop */
121 #define ICMP_UNREACH_SRCFAIL 5 /* src route failed */
122 #define ICMP_UNREACH_NET_UNKNOWN 6 /* unknown net */
123 #define ICMP_UNREACH_HOST_UNKNOWN 7 /* unknown host */
124 #define ICMP_UNREACH_ISOLATED 8 /* src host isolated */
125 #define ICMP_UNREACH_NET_PROHIB 9 /* prohibited access */
126 #define ICMP_UNREACH_HOST_PROHIB 10 /* ditto */
127 #define ICMP_UNREACH_TOSNET 11 /* bad tos for net */
128 #define ICMP_UNREACH_TOSHOST 12 /* bad tos for host */
129 #define ICMP_SOURCEQUENCH 4 /* packet lost, slow down */
130 #define ICMP_REDIRECT 5 /* shorter route, codes: */
131 #define ICMP_REDIRECT_NET 0 /* for network */
132 #define ICMP_REDIRECT_HOST 1 /* for host */
133 #define ICMP_REDIRECT_TOSNET 2 /* for tos and net */
134 #define ICMP_REDIRECT_TOSHOST 3 /* for tos and host */
135 #define ICMP_ECHO 8 /* echo service */
136 #define ICMP_ROUTERADVERT 9 /* router advertisement */
137 #define ICMP_ROUTERSOLICIT 10 /* router solicitation */
138 #define ICMP_TIMXCEED 11 /* time exceeded, code: */
139 #define ICMP_TIMXCEED_INTRANS 0 /* ttl==0 in transit */
140 #define ICMP_TIMXCEED_REASS 1 /* ttl==0 in reass */
141 #define ICMP_PARAMPROB 12 /* ip header bad */
142 #define ICMP_PARAMPROB_OPTABSENT 1 /* req. opt. absent */
143 #define ICMP_TSTAMP 13 /* timestamp request */
144 #define ICMP_TSTAMPREPLY 14 /* timestamp reply */
145 #define ICMP_IREQ 15 /* information request */
146 #define ICMP_IREQREPLY 16 /* information reply */
147 #define ICMP_MASKREQ 17 /* address mask request */
148 #define ICMP_MASKREPLY 18 /* address mask reply */
149
150 #define ICMP_MAXTYPE 18
151
152 #define ICMP_INFOTYPE(type) \
153 ((type) == ICMP_ECHOREPLY || (type) == ICMP_ECHO || \
154 (type) == ICMP_ROUTERADVERT || (type) == ICMP_ROUTERSOLICIT || \
155 (type) == ICMP_TSTAMP || (type) == ICMP_TSTAMPREPLY || \
156 (type) == ICMP_IREQ || (type) == ICMP_IREQREPLY || \
157 (type) == ICMP_MASKREQ || (type) == ICMP_MASKREPLY)
158 #define ICMP_MPLS_EXT_TYPE(type) \
159 ((type) == ICMP_UNREACH || \
160 (type) == ICMP_TIMXCEED || \
161 (type) == ICMP_PARAMPROB)
162 /* rfc1700 */
163 #ifndef ICMP_UNREACH_NET_UNKNOWN
164 #define ICMP_UNREACH_NET_UNKNOWN 6 /* destination net unknown */
165 #endif
166 #ifndef ICMP_UNREACH_HOST_UNKNOWN
167 #define ICMP_UNREACH_HOST_UNKNOWN 7 /* destination host unknown */
168 #endif
169 #ifndef ICMP_UNREACH_ISOLATED
170 #define ICMP_UNREACH_ISOLATED 8 /* source host isolated */
171 #endif
172 #ifndef ICMP_UNREACH_NET_PROHIB
173 #define ICMP_UNREACH_NET_PROHIB 9 /* admin prohibited net */
174 #endif
175 #ifndef ICMP_UNREACH_HOST_PROHIB
176 #define ICMP_UNREACH_HOST_PROHIB 10 /* admin prohibited host */
177 #endif
178 #ifndef ICMP_UNREACH_TOSNET
179 #define ICMP_UNREACH_TOSNET 11 /* tos prohibited net */
180 #endif
181 #ifndef ICMP_UNREACH_TOSHOST
182 #define ICMP_UNREACH_TOSHOST 12 /* tos prohibited host */
183 #endif
184
185 /* rfc1716 */
186 #ifndef ICMP_UNREACH_FILTER_PROHIB
187 #define ICMP_UNREACH_FILTER_PROHIB 13 /* admin prohibited filter */
188 #endif
189 #ifndef ICMP_UNREACH_HOST_PRECEDENCE
190 #define ICMP_UNREACH_HOST_PRECEDENCE 14 /* host precedence violation */
191 #endif
192 #ifndef ICMP_UNREACH_PRECEDENCE_CUTOFF
193 #define ICMP_UNREACH_PRECEDENCE_CUTOFF 15 /* precedence cutoff */
194 #endif
195
196 /* Most of the icmp types */
197 static struct tok icmp2str[] = {
198 { ICMP_ECHOREPLY, "echo reply" },
199 { ICMP_SOURCEQUENCH, "source quench" },
200 { ICMP_ECHO, "echo request" },
201 { ICMP_ROUTERSOLICIT, "router solicitation" },
202 { ICMP_TSTAMP, "time stamp request" },
203 { ICMP_TSTAMPREPLY, "time stamp reply" },
204 { ICMP_IREQ, "information request" },
205 { ICMP_IREQREPLY, "information reply" },
206 { ICMP_MASKREQ, "address mask request" },
207 { 0, NULL }
208 };
209
210 /* Formats for most of the ICMP_UNREACH codes */
211 static struct tok unreach2str[] = {
212 { ICMP_UNREACH_NET, "net %s unreachable" },
213 { ICMP_UNREACH_HOST, "host %s unreachable" },
214 { ICMP_UNREACH_SRCFAIL,
215 "%s unreachable - source route failed" },
216 { ICMP_UNREACH_NET_UNKNOWN, "net %s unreachable - unknown" },
217 { ICMP_UNREACH_HOST_UNKNOWN, "host %s unreachable - unknown" },
218 { ICMP_UNREACH_ISOLATED,
219 "%s unreachable - source host isolated" },
220 { ICMP_UNREACH_NET_PROHIB,
221 "net %s unreachable - admin prohibited" },
222 { ICMP_UNREACH_HOST_PROHIB,
223 "host %s unreachable - admin prohibited" },
224 { ICMP_UNREACH_TOSNET,
225 "net %s unreachable - tos prohibited" },
226 { ICMP_UNREACH_TOSHOST,
227 "host %s unreachable - tos prohibited" },
228 { ICMP_UNREACH_FILTER_PROHIB,
229 "host %s unreachable - admin prohibited filter" },
230 { ICMP_UNREACH_HOST_PRECEDENCE,
231 "host %s unreachable - host precedence violation" },
232 { ICMP_UNREACH_PRECEDENCE_CUTOFF,
233 "host %s unreachable - precedence cutoff" },
234 { 0, NULL }
235 };
236
237 /* Formats for the ICMP_REDIRECT codes */
238 static struct tok type2str[] = {
239 { ICMP_REDIRECT_NET, "redirect %s to net %s" },
240 { ICMP_REDIRECT_HOST, "redirect %s to host %s" },
241 { ICMP_REDIRECT_TOSNET, "redirect-tos %s to net %s" },
242 { ICMP_REDIRECT_TOSHOST, "redirect-tos %s to host %s" },
243 { 0, NULL }
244 };
245
246 /* rfc1191 */
247 struct mtu_discovery {
248 u_int16_t unused;
249 u_int16_t nexthopmtu;
250 };
251
252 /* rfc1256 */
253 struct ih_rdiscovery {
254 u_int8_t ird_addrnum;
255 u_int8_t ird_addrsiz;
256 u_int16_t ird_lifetime;
257 };
258
259 struct id_rdiscovery {
260 u_int32_t ird_addr;
261 u_int32_t ird_pref;
262 };
263
264 /*
265 * draft-bonica-internet-icmp-08
266 *
267 * The Destination Unreachable, Time Exceeded
268 * and Parameter Problem messages are slighly changed as per
269 * the above draft. A new Length field gets added to give
270 * the caller an idea about the length of the piggypacked
271 * IP packet before the MPLS extension header starts.
272 *
273 * The Length field represents length of the padded "original datagram"
274 * field measured in 32-bit words.
275 *
276 * 0 1 2 3
277 * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
278 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
279 * | Type | Code | Checksum |
280 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
281 * | unused | Length | unused |
282 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
283 * | Internet Header + leading octets of original datagram |
284 * | |
285 * | // |
286 * | |
287 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
288 */
289
290 struct icmp_ext_t {
291 u_int8_t icmp_type;
292 u_int8_t icmp_code;
293 u_int8_t icmp_checksum[2];
294 u_int8_t icmp_reserved;
295 u_int8_t icmp_length;
296 u_int8_t icmp_reserved2[2];
297 u_int8_t icmp_ext_legacy_header[128]; /* extension header starts 128 bytes after ICMP header */
298 u_int8_t icmp_ext_version_res[2];
299 u_int8_t icmp_ext_checksum[2];
300 u_int8_t icmp_ext_data[1];
301 };
302
303 struct icmp_mpls_ext_common_header_t {
304 };
305
306 struct icmp_mpls_ext_object_header_t {
307 u_int8_t length[2];
308 u_int8_t class_num;
309 u_int8_t ctype;
310 };
311
312 static const struct tok icmp_mpls_ext_obj_values[] = {
313 { 1, "MPLS Stack Entry" },
314 { 2, "Extended Payload" },
315 { 0, NULL}
316 };
317
318 /* prototypes */
319 const char *icmp_tstamp_print(u_int);
320
321 /* print the milliseconds since midnight UTC */
322 const char *
323 icmp_tstamp_print(u_int tstamp) {
324 u_int msec,sec,min,hrs;
325
326 static char buf[64];
327
328 msec = tstamp % 1000;
329 sec = tstamp / 1000;
330 min = sec / 60; sec -= min * 60;
331 hrs = min / 60; min -= hrs * 60;
332 snprintf(buf, sizeof(buf), "%02u:%02u:%02u.%03u",hrs,min,sec,msec);
333 return buf;
334 }
335
336 void
337 icmp_print(const u_char *bp, u_int plen, const u_char *bp2, int fragmented)
338 {
339 char *cp;
340 const struct icmp *dp;
341 const struct icmp_ext_t *ext_dp;
342 const struct ip *ip;
343 const char *str, *fmt;
344 const struct ip *oip;
345 const struct udphdr *ouh;
346 const u_int8_t *obj_tptr;
347 u_int32_t raw_label;
348 const u_char *snapend_save;
349 const struct icmp_mpls_ext_object_header_t *icmp_mpls_ext_object_header;
350 u_int hlen, dport, mtu, obj_tlen, obj_class_num, obj_ctype;
351 char buf[MAXHOSTNAMELEN + 100];
352
353 dp = (struct icmp *)bp;
354 ext_dp = (struct icmp_ext_t *)bp;
355 ip = (struct ip *)bp2;
356 str = buf;
357
358 TCHECK(dp->icmp_code);
359 switch (dp->icmp_type) {
360
361 case ICMP_ECHO:
362 case ICMP_ECHOREPLY:
363 TCHECK(dp->icmp_seq);
364 (void)snprintf(buf, sizeof(buf), "echo %s, id %u, seq %u",
365 dp->icmp_type == ICMP_ECHO ?
366 "request" : "reply",
367 EXTRACT_16BITS(&dp->icmp_id),
368 EXTRACT_16BITS(&dp->icmp_seq));
369 break;
370
371 case ICMP_UNREACH:
372 TCHECK(dp->icmp_ip.ip_dst);
373 switch (dp->icmp_code) {
374
375 case ICMP_UNREACH_PROTOCOL:
376 TCHECK(dp->icmp_ip.ip_p);
377 (void)snprintf(buf, sizeof(buf),
378 "%s protocol %d unreachable",
379 ipaddr_string(&dp->icmp_ip.ip_dst),
380 dp->icmp_ip.ip_p);
381 break;
382
383 case ICMP_UNREACH_PORT:
384 TCHECK(dp->icmp_ip.ip_p);
385 oip = &dp->icmp_ip;
386 hlen = IP_HL(oip) * 4;
387 ouh = (struct udphdr *)(((u_char *)oip) + hlen);
388 TCHECK(ouh->uh_dport);
389 dport = EXTRACT_16BITS(&ouh->uh_dport);
390 switch (oip->ip_p) {
391
392 case IPPROTO_TCP:
393 (void)snprintf(buf, sizeof(buf),
394 "%s tcp port %s unreachable",
395 ipaddr_string(&oip->ip_dst),
396 tcpport_string(dport));
397 break;
398
399 case IPPROTO_UDP:
400 (void)snprintf(buf, sizeof(buf),
401 "%s udp port %s unreachable",
402 ipaddr_string(&oip->ip_dst),
403 udpport_string(dport));
404 break;
405
406 default:
407 (void)snprintf(buf, sizeof(buf),
408 "%s protocol %d port %d unreachable",
409 ipaddr_string(&oip->ip_dst),
410 oip->ip_p, dport);
411 break;
412 }
413 break;
414
415 case ICMP_UNREACH_NEEDFRAG:
416 {
417 register const struct mtu_discovery *mp;
418 mp = (struct mtu_discovery *)&dp->icmp_void;
419 mtu = EXTRACT_16BITS(&mp->nexthopmtu);
420 if (mtu) {
421 (void)snprintf(buf, sizeof(buf),
422 "%s unreachable - need to frag (mtu %d)",
423 ipaddr_string(&dp->icmp_ip.ip_dst), mtu);
424 } else {
425 (void)snprintf(buf, sizeof(buf),
426 "%s unreachable - need to frag",
427 ipaddr_string(&dp->icmp_ip.ip_dst));
428 }
429 }
430 break;
431
432 default:
433 fmt = tok2str(unreach2str, "#%d %%s unreachable",
434 dp->icmp_code);
435 (void)snprintf(buf, sizeof(buf), fmt,
436 ipaddr_string(&dp->icmp_ip.ip_dst));
437 break;
438 }
439 break;
440
441 case ICMP_REDIRECT:
442 TCHECK(dp->icmp_ip.ip_dst);
443 fmt = tok2str(type2str, "redirect-#%d %%s to net %%s",
444 dp->icmp_code);
445 (void)snprintf(buf, sizeof(buf), fmt,
446 ipaddr_string(&dp->icmp_ip.ip_dst),
447 ipaddr_string(&dp->icmp_gwaddr));
448 break;
449
450 case ICMP_ROUTERADVERT:
451 {
452 register const struct ih_rdiscovery *ihp;
453 register const struct id_rdiscovery *idp;
454 u_int lifetime, num, size;
455
456 (void)snprintf(buf, sizeof(buf), "router advertisement");
457 cp = buf + strlen(buf);
458
459 ihp = (struct ih_rdiscovery *)&dp->icmp_void;
460 TCHECK(*ihp);
461 (void)strncpy(cp, " lifetime ", sizeof(buf) - (cp - buf));
462 cp = buf + strlen(buf);
463 lifetime = EXTRACT_16BITS(&ihp->ird_lifetime);
464 if (lifetime < 60) {
465 (void)snprintf(cp, sizeof(buf) - (cp - buf), "%u",
466 lifetime);
467 } else if (lifetime < 60 * 60) {
468 (void)snprintf(cp, sizeof(buf) - (cp - buf), "%u:%02u",
469 lifetime / 60, lifetime % 60);
470 } else {
471 (void)snprintf(cp, sizeof(buf) - (cp - buf),
472 "%u:%02u:%02u",
473 lifetime / 3600,
474 (lifetime % 3600) / 60,
475 lifetime % 60);
476 }
477 cp = buf + strlen(buf);
478
479 num = ihp->ird_addrnum;
480 (void)snprintf(cp, sizeof(buf) - (cp - buf), " %d:", num);
481 cp = buf + strlen(buf);
482
483 size = ihp->ird_addrsiz;
484 if (size != 2) {
485 (void)snprintf(cp, sizeof(buf) - (cp - buf),
486 " [size %d]", size);
487 break;
488 }
489 idp = (struct id_rdiscovery *)&dp->icmp_data;
490 while (num-- > 0) {
491 TCHECK(*idp);
492 (void)snprintf(cp, sizeof(buf) - (cp - buf), " {%s %u}",
493 ipaddr_string(&idp->ird_addr),
494 EXTRACT_32BITS(&idp->ird_pref));
495 cp = buf + strlen(buf);
496 ++idp;
497 }
498 }
499 break;
500
501 case ICMP_TIMXCEED:
502 TCHECK(dp->icmp_ip.ip_dst);
503 switch (dp->icmp_code) {
504
505 case ICMP_TIMXCEED_INTRANS:
506 str = "time exceeded in-transit";
507 break;
508
509 case ICMP_TIMXCEED_REASS:
510 str = "ip reassembly time exceeded";
511 break;
512
513 default:
514 (void)snprintf(buf, sizeof(buf), "time exceeded-#%d",
515 dp->icmp_code);
516 break;
517 }
518 break;
519
520 case ICMP_PARAMPROB:
521 if (dp->icmp_code)
522 (void)snprintf(buf, sizeof(buf),
523 "parameter problem - code %d", dp->icmp_code);
524 else {
525 TCHECK(dp->icmp_pptr);
526 (void)snprintf(buf, sizeof(buf),
527 "parameter problem - octet %d", dp->icmp_pptr);
528 }
529 break;
530
531 case ICMP_MASKREPLY:
532 TCHECK(dp->icmp_mask);
533 (void)snprintf(buf, sizeof(buf), "address mask is 0x%08x",
534 EXTRACT_32BITS(&dp->icmp_mask));
535 break;
536
537 case ICMP_TSTAMP:
538 TCHECK(dp->icmp_seq);
539 (void)snprintf(buf, sizeof(buf),
540 "time stamp query id %u seq %u",
541 EXTRACT_16BITS(&dp->icmp_id),
542 EXTRACT_16BITS(&dp->icmp_seq));
543 break;
544
545 case ICMP_TSTAMPREPLY:
546 TCHECK(dp->icmp_ttime);
547 (void)snprintf(buf, sizeof(buf),
548 "time stamp reply id %u seq %u: org %s",
549 EXTRACT_16BITS(&dp->icmp_id),
550 EXTRACT_16BITS(&dp->icmp_seq),
551 icmp_tstamp_print(EXTRACT_32BITS(&dp->icmp_otime)));
552
553 (void)snprintf(buf+strlen(buf),sizeof(buf)-strlen(buf),", recv %s",
554 icmp_tstamp_print(EXTRACT_32BITS(&dp->icmp_rtime)));
555 (void)snprintf(buf+strlen(buf),sizeof(buf)-strlen(buf),", xmit %s",
556 icmp_tstamp_print(EXTRACT_32BITS(&dp->icmp_ttime)));
557 break;
558
559 default:
560 str = tok2str(icmp2str, "type-#%d", dp->icmp_type);
561 break;
562 }
563 (void)printf("ICMP %s, length %u", str, plen);
564 if (vflag && !fragmented) { /* don't attempt checksumming if this is a frag */
565 u_int16_t sum, icmp_sum;
566 if (TTEST2(*bp, plen)) {
567 sum = in_cksum((u_short*)dp, plen, 0);
568 if (sum != 0) {
569 icmp_sum = EXTRACT_16BITS(&dp->icmp_cksum);
570 (void)printf(" (wrong icmp cksum %x (->%x)!)",
571 icmp_sum,
572 in_cksum_shouldbe(icmp_sum, sum));
573 }
574 }
575 }
576
577 /*
578 * print the remnants of the IP packet.
579 * save the snaplength as this may get overidden in the IP printer.
580 */
581 if (vflag >= 1 && !ICMP_INFOTYPE(dp->icmp_type)) {
582 bp += 8;
583 (void)printf("\n\t");
584 ip = (struct ip *)bp;
585 snaplen = snapend - bp;
586 snapend_save = snapend;
587 ip_print(gndo, bp, EXTRACT_16BITS(&ip->ip_len));
588 snapend = snapend_save;
589 }
590
591 /*
592 * Check if the extended ICMP header indicates that there is
593 * MPLS extension header present for the "interesting" ICMP types.
594 */
595 if (vflag >= 1 && plen > ICMP_EXTD_MINLEN &&
596 ext_dp->icmp_length && ICMP_MPLS_EXT_TYPE(dp->icmp_type)) {
597
598 TCHECK(*ext_dp);
599 printf("\n\tMPLS extension v%u",
600 ICMP_MPLS_EXT_EXTRACT_VERSION(*(ext_dp->icmp_ext_version_res)));
601
602 /*
603 * Sanity checking of the header.
604 */
605 if (ICMP_MPLS_EXT_EXTRACT_VERSION(*(ext_dp->icmp_ext_version_res)) !=
606 ICMP_MPLS_EXT_VERSION) {
607 printf(" packet not supported");
608 return;
609 }
610
611 hlen = plen - ICMP_EXTD_MINLEN;
612 printf(", checksum 0x%04x (unverified), length %u", /* FIXME */
613 EXTRACT_16BITS(ext_dp->icmp_ext_checksum),
614 hlen);
615
616 hlen -= 4; /* subtract common header size */
617 obj_tptr = (u_int8_t *)ext_dp->icmp_ext_data;
618
619 while (hlen > sizeof(struct icmp_mpls_ext_object_header_t)) {
620
621 icmp_mpls_ext_object_header = (struct icmp_mpls_ext_object_header_t *)obj_tptr;
622 TCHECK(*icmp_mpls_ext_object_header);
623 obj_tlen = EXTRACT_16BITS(icmp_mpls_ext_object_header->length);
624 obj_class_num = icmp_mpls_ext_object_header->class_num;
625 obj_ctype = icmp_mpls_ext_object_header->ctype;
626 obj_tptr += sizeof(struct icmp_mpls_ext_object_header_t);
627
628 printf("\n\t %s Object (%u), Class-Type: %u, length %u",
629 tok2str(icmp_mpls_ext_obj_values,"unknown",obj_class_num),
630 obj_class_num,
631 obj_ctype,
632 obj_tlen);
633
634 hlen-=sizeof(struct icmp_mpls_ext_object_header_t); /* length field includes tlv header */
635
636 /* infinite loop protection */
637 if ((obj_class_num == 0) ||
638 (obj_tlen < sizeof(struct icmp_mpls_ext_object_header_t))) {
639 return;
640 }
641 obj_tlen-=sizeof(struct icmp_mpls_ext_object_header_t);
642
643 switch (obj_class_num) {
644 case 1:
645 switch(obj_ctype) {
646 case 1:
647 TCHECK2(*obj_tptr, 4);
648 raw_label = EXTRACT_32BITS(obj_tptr);
649 printf("\n\t label %u, exp %u", MPLS_LABEL(raw_label), MPLS_EXP(raw_label));
650 if (MPLS_STACK(raw_label))
651 printf(", [S]");
652 printf(", ttl %u", MPLS_TTL(raw_label));
653 break;
654 default:
655 print_unknown_data(obj_tptr, "\n\t ", obj_tlen);
656 }
657 break;
658
659 /*
660 * FIXME those are the defined objects that lack a decoder
661 * you are welcome to contribute code ;-)
662 */
663 case 2:
664 default:
665 print_unknown_data(obj_tptr, "\n\t ", obj_tlen);
666 break;
667 }
668 if (hlen < obj_tlen)
669 break;
670 hlen -= obj_tlen;
671 obj_tptr += obj_tlen;
672 }
673 }
674
675 return;
676 trunc:
677 fputs("[|icmp]", stdout);
678 }
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