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Remove some now redundant ND_TCHECK_4() calls
[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 /* \summary: Internet Control Message Protocol (ICMP) printer */
23
24 #ifdef HAVE_CONFIG_H
25 #include <config.h>
26 #endif
27
28 #include "netdissect-stdinc.h"
29
30 #include <stdio.h>
31 #include <string.h>
32
33 #include "netdissect.h"
34 #include "addrtoname.h"
35 #include "extract.h"
36
37 #include "ip.h"
38 #include "udp.h"
39 #include "ipproto.h"
40 #include "mpls.h"
41
42 /*
43 * Interface Control Message Protocol Definitions.
44 * Per RFC 792, September 1981.
45 */
46
47 /*
48 * Structure of an icmp header.
49 */
50 struct icmp {
51 nd_uint8_t icmp_type; /* type of message, see below */
52 nd_uint8_t icmp_code; /* type sub code */
53 nd_uint16_t icmp_cksum; /* ones complement cksum of struct */
54 union {
55 nd_uint8_t ih_pptr; /* ICMP_PARAMPROB */
56 nd_ipv4 ih_gwaddr; /* ICMP_REDIRECT */
57 struct ih_idseq {
58 nd_uint16_t icd_id;
59 nd_uint16_t icd_seq;
60 } ih_idseq;
61 nd_uint32_t ih_void;
62 } icmp_hun;
63 #define icmp_pptr icmp_hun.ih_pptr
64 #define icmp_gwaddr icmp_hun.ih_gwaddr
65 #define icmp_id icmp_hun.ih_idseq.icd_id
66 #define icmp_seq icmp_hun.ih_idseq.icd_seq
67 #define icmp_void icmp_hun.ih_void
68 union {
69 struct id_ts {
70 nd_uint32_t its_otime;
71 nd_uint32_t its_rtime;
72 nd_uint32_t its_ttime;
73 } id_ts;
74 struct id_ip {
75 struct ip idi_ip;
76 /* options and then 64 bits of data */
77 } id_ip;
78 nd_uint32_t id_mask;
79 nd_byte id_data[1];
80 } icmp_dun;
81 #define icmp_otime icmp_dun.id_ts.its_otime
82 #define icmp_rtime icmp_dun.id_ts.its_rtime
83 #define icmp_ttime icmp_dun.id_ts.its_ttime
84 #define icmp_ip icmp_dun.id_ip.idi_ip
85 #define icmp_mask icmp_dun.id_mask
86 #define icmp_data icmp_dun.id_data
87 };
88
89 #define ICMP_MPLS_EXT_EXTRACT_VERSION(x) (((x)&0xf0)>>4)
90 #define ICMP_MPLS_EXT_VERSION 2
91
92 /*
93 * Lower bounds on packet lengths for various types.
94 * For the error advice packets must first insure that the
95 * packet is large enought to contain the returned ip header.
96 * Only then can we do the check to see if 64 bits of packet
97 * data have been returned, since we need to check the returned
98 * ip header length.
99 */
100 #define ICMP_MINLEN 8 /* abs minimum */
101 #define ICMP_EXTD_MINLEN (156 - sizeof (struct ip)) /* draft-bonica-internet-icmp-08 */
102 #define ICMP_TSLEN (8 + 3 * sizeof (uint32_t)) /* timestamp */
103 #define ICMP_MASKLEN 12 /* address mask */
104 #define ICMP_ADVLENMIN (8 + sizeof (struct ip) + 8) /* min */
105 #define ICMP_ADVLEN(p) (8 + (IP_HL(&(p)->icmp_ip) << 2) + 8)
106 /* N.B.: must separately check that ip_hl >= 5 */
107
108 /*
109 * Definition of type and code field values.
110 */
111 #define ICMP_ECHOREPLY 0 /* echo reply */
112 #define ICMP_UNREACH 3 /* dest unreachable, codes: */
113 #define ICMP_UNREACH_NET 0 /* bad net */
114 #define ICMP_UNREACH_HOST 1 /* bad host */
115 #define ICMP_UNREACH_PROTOCOL 2 /* bad protocol */
116 #define ICMP_UNREACH_PORT 3 /* bad port */
117 #define ICMP_UNREACH_NEEDFRAG 4 /* IP_DF caused drop */
118 #define ICMP_UNREACH_SRCFAIL 5 /* src route failed */
119 #define ICMP_UNREACH_NET_UNKNOWN 6 /* unknown net */
120 #define ICMP_UNREACH_HOST_UNKNOWN 7 /* unknown host */
121 #define ICMP_UNREACH_ISOLATED 8 /* src host isolated */
122 #define ICMP_UNREACH_NET_PROHIB 9 /* prohibited access */
123 #define ICMP_UNREACH_HOST_PROHIB 10 /* ditto */
124 #define ICMP_UNREACH_TOSNET 11 /* bad tos for net */
125 #define ICMP_UNREACH_TOSHOST 12 /* bad tos for host */
126 #define ICMP_SOURCEQUENCH 4 /* packet lost, slow down */
127 #define ICMP_REDIRECT 5 /* shorter route, codes: */
128 #define ICMP_REDIRECT_NET 0 /* for network */
129 #define ICMP_REDIRECT_HOST 1 /* for host */
130 #define ICMP_REDIRECT_TOSNET 2 /* for tos and net */
131 #define ICMP_REDIRECT_TOSHOST 3 /* for tos and host */
132 #define ICMP_ECHO 8 /* echo service */
133 #define ICMP_ROUTERADVERT 9 /* router advertisement */
134 #define ICMP_ROUTERSOLICIT 10 /* router solicitation */
135 #define ICMP_TIMXCEED 11 /* time exceeded, code: */
136 #define ICMP_TIMXCEED_INTRANS 0 /* ttl==0 in transit */
137 #define ICMP_TIMXCEED_REASS 1 /* ttl==0 in reass */
138 #define ICMP_PARAMPROB 12 /* ip header bad */
139 #define ICMP_PARAMPROB_OPTABSENT 1 /* req. opt. absent */
140 #define ICMP_TSTAMP 13 /* timestamp request */
141 #define ICMP_TSTAMPREPLY 14 /* timestamp reply */
142 #define ICMP_IREQ 15 /* information request */
143 #define ICMP_IREQREPLY 16 /* information reply */
144 #define ICMP_MASKREQ 17 /* address mask request */
145 #define ICMP_MASKREPLY 18 /* address mask reply */
146
147 #define ICMP_MAXTYPE 18
148
149 #define ICMP_ERRTYPE(type) \
150 ((type) == ICMP_UNREACH || (type) == ICMP_SOURCEQUENCH || \
151 (type) == ICMP_REDIRECT || (type) == ICMP_TIMXCEED || \
152 (type) == ICMP_PARAMPROB)
153 #define ICMP_MPLS_EXT_TYPE(type) \
154 ((type) == ICMP_UNREACH || \
155 (type) == ICMP_TIMXCEED || \
156 (type) == ICMP_PARAMPROB)
157 /* rfc1700 */
158 #ifndef ICMP_UNREACH_NET_UNKNOWN
159 #define ICMP_UNREACH_NET_UNKNOWN 6 /* destination net unknown */
160 #endif
161 #ifndef ICMP_UNREACH_HOST_UNKNOWN
162 #define ICMP_UNREACH_HOST_UNKNOWN 7 /* destination host unknown */
163 #endif
164 #ifndef ICMP_UNREACH_ISOLATED
165 #define ICMP_UNREACH_ISOLATED 8 /* source host isolated */
166 #endif
167 #ifndef ICMP_UNREACH_NET_PROHIB
168 #define ICMP_UNREACH_NET_PROHIB 9 /* admin prohibited net */
169 #endif
170 #ifndef ICMP_UNREACH_HOST_PROHIB
171 #define ICMP_UNREACH_HOST_PROHIB 10 /* admin prohibited host */
172 #endif
173 #ifndef ICMP_UNREACH_TOSNET
174 #define ICMP_UNREACH_TOSNET 11 /* tos prohibited net */
175 #endif
176 #ifndef ICMP_UNREACH_TOSHOST
177 #define ICMP_UNREACH_TOSHOST 12 /* tos prohibited host */
178 #endif
179
180 /* rfc1716 */
181 #ifndef ICMP_UNREACH_FILTER_PROHIB
182 #define ICMP_UNREACH_FILTER_PROHIB 13 /* admin prohibited filter */
183 #endif
184 #ifndef ICMP_UNREACH_HOST_PRECEDENCE
185 #define ICMP_UNREACH_HOST_PRECEDENCE 14 /* host precedence violation */
186 #endif
187 #ifndef ICMP_UNREACH_PRECEDENCE_CUTOFF
188 #define ICMP_UNREACH_PRECEDENCE_CUTOFF 15 /* precedence cutoff */
189 #endif
190
191 /* Most of the icmp types */
192 static const struct tok icmp2str[] = {
193 { ICMP_ECHOREPLY, "echo reply" },
194 { ICMP_SOURCEQUENCH, "source quench" },
195 { ICMP_ECHO, "echo request" },
196 { ICMP_ROUTERSOLICIT, "router solicitation" },
197 { ICMP_TSTAMP, "time stamp request" },
198 { ICMP_TSTAMPREPLY, "time stamp reply" },
199 { ICMP_IREQ, "information request" },
200 { ICMP_IREQREPLY, "information reply" },
201 { ICMP_MASKREQ, "address mask request" },
202 { 0, NULL }
203 };
204
205 /* rfc1191 */
206 struct mtu_discovery {
207 nd_uint16_t unused;
208 nd_uint16_t nexthopmtu;
209 };
210
211 /* rfc1256 */
212 struct ih_rdiscovery {
213 nd_uint8_t ird_addrnum;
214 nd_uint8_t ird_addrsiz;
215 nd_uint16_t ird_lifetime;
216 };
217
218 struct id_rdiscovery {
219 nd_uint32_t ird_addr;
220 nd_uint32_t ird_pref;
221 };
222
223 /*
224 * draft-bonica-internet-icmp-08
225 *
226 * The Destination Unreachable, Time Exceeded
227 * and Parameter Problem messages are slightly changed as per
228 * the above draft. A new Length field gets added to give
229 * the caller an idea about the length of the piggypacked
230 * IP packet before the MPLS extension header starts.
231 *
232 * The Length field represents length of the padded "original datagram"
233 * field measured in 32-bit words.
234 *
235 * 0 1 2 3
236 * 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
237 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
238 * | Type | Code | Checksum |
239 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
240 * | unused | Length | unused |
241 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
242 * | Internet Header + leading octets of original datagram |
243 * | |
244 * | // |
245 * | |
246 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
247 */
248
249 struct icmp_ext_t {
250 nd_uint8_t icmp_type;
251 nd_uint8_t icmp_code;
252 nd_uint16_t icmp_checksum;
253 nd_byte icmp_reserved;
254 nd_uint8_t icmp_length;
255 nd_byte icmp_reserved2[2];
256 nd_byte icmp_ext_legacy_header[128]; /* extension header starts 128 bytes after ICMP header */
257 nd_byte icmp_ext_version_res[2];
258 nd_uint16_t icmp_ext_checksum;
259 nd_byte icmp_ext_data[1];
260 };
261
262 struct icmp_mpls_ext_object_header_t {
263 nd_uint16_t length;
264 nd_uint8_t class_num;
265 nd_uint8_t ctype;
266 };
267
268 static const struct tok icmp_mpls_ext_obj_values[] = {
269 { 1, "MPLS Stack Entry" },
270 { 2, "Extended Payload" },
271 { 0, NULL}
272 };
273
274 /* prototypes */
275 const char *icmp_tstamp_print(u_int);
276
277 /* print the milliseconds since midnight UTC */
278 const char *
279 icmp_tstamp_print(u_int tstamp)
280 {
281 u_int msec,sec,min,hrs;
282
283 static char buf[64];
284
285 msec = tstamp % 1000;
286 sec = tstamp / 1000;
287 min = sec / 60; sec -= min * 60;
288 hrs = min / 60; min -= hrs * 60;
289 snprintf(buf, sizeof(buf), "%02u:%02u:%02u.%03u",hrs,min,sec,msec);
290 return buf;
291 }
292
293 void
294 icmp_print(netdissect_options *ndo, const u_char *bp, u_int plen, const u_char *bp2,
295 int fragmented)
296 {
297 char *cp;
298 const struct icmp *dp;
299 uint8_t icmp_type, icmp_code;
300 const struct icmp_ext_t *ext_dp;
301 const struct ip *ip;
302 const char *str;
303 const struct ip *oip;
304 uint8_t ip_proto;
305 const struct udphdr *ouh;
306 const uint8_t *obj_tptr;
307 uint32_t raw_label;
308 const u_char *snapend_save;
309 const struct icmp_mpls_ext_object_header_t *icmp_mpls_ext_object_header;
310 u_int hlen, mtu, obj_tlen, obj_class_num, obj_ctype;
311 uint16_t dport;
312 char buf[MAXHOSTNAMELEN + 100];
313 struct cksum_vec vec[1];
314
315 ndo->ndo_protocol = "icmp";
316 dp = (const struct icmp *)bp;
317 ext_dp = (const struct icmp_ext_t *)bp;
318 ip = (const struct ip *)bp2;
319 str = buf;
320
321 icmp_type = GET_U_1(dp->icmp_type);
322 icmp_code = GET_U_1(dp->icmp_code);
323 switch (icmp_type) {
324
325 case ICMP_ECHO:
326 case ICMP_ECHOREPLY:
327 ND_TCHECK_2(dp->icmp_seq);
328 (void)snprintf(buf, sizeof(buf), "echo %s, id %u, seq %u",
329 icmp_type == ICMP_ECHO ?
330 "request" : "reply",
331 GET_BE_U_2(dp->icmp_id),
332 GET_BE_U_2(dp->icmp_seq));
333 break;
334
335 case ICMP_UNREACH:
336 switch (icmp_code) {
337
338 case ICMP_UNREACH_NET:
339 (void)snprintf(buf, sizeof(buf),
340 "net %s unreachable",
341 GET_IPADDR_STRING(dp->icmp_ip.ip_dst));
342 break;
343
344 case ICMP_UNREACH_HOST:
345 (void)snprintf(buf, sizeof(buf),
346 "host %s unreachable",
347 GET_IPADDR_STRING(dp->icmp_ip.ip_dst));
348 break;
349
350 case ICMP_UNREACH_PROTOCOL:
351 ND_TCHECK_1(dp->icmp_ip.ip_p);
352 (void)snprintf(buf, sizeof(buf),
353 "%s protocol %u unreachable",
354 GET_IPADDR_STRING(dp->icmp_ip.ip_dst),
355 GET_U_1(dp->icmp_ip.ip_p));
356 break;
357
358 case ICMP_UNREACH_PORT:
359 ND_TCHECK_1(dp->icmp_ip.ip_p);
360 oip = &dp->icmp_ip;
361 hlen = IP_HL(oip) * 4;
362 ouh = (const struct udphdr *)(((const u_char *)oip) + hlen);
363 dport = GET_BE_U_2(ouh->uh_dport);
364 ip_proto = GET_U_1(oip->ip_p);
365 switch (ip_proto) {
366
367 case IPPROTO_TCP:
368 (void)snprintf(buf, sizeof(buf),
369 "%s tcp port %s unreachable",
370 GET_IPADDR_STRING(oip->ip_dst),
371 tcpport_string(ndo, dport));
372 break;
373
374 case IPPROTO_UDP:
375 (void)snprintf(buf, sizeof(buf),
376 "%s udp port %s unreachable",
377 GET_IPADDR_STRING(oip->ip_dst),
378 udpport_string(ndo, dport));
379 break;
380
381 default:
382 (void)snprintf(buf, sizeof(buf),
383 "%s protocol %u port %u unreachable",
384 GET_IPADDR_STRING(oip->ip_dst),
385 ip_proto, dport);
386 break;
387 }
388 break;
389
390 case ICMP_UNREACH_NEEDFRAG:
391 {
392 const struct mtu_discovery *mp;
393 mp = (const struct mtu_discovery *)(const u_char *)&dp->icmp_void;
394 mtu = GET_BE_U_2(mp->nexthopmtu);
395 if (mtu) {
396 (void)snprintf(buf, sizeof(buf),
397 "%s unreachable - need to frag (mtu %u)",
398 GET_IPADDR_STRING(dp->icmp_ip.ip_dst), mtu);
399 } else {
400 (void)snprintf(buf, sizeof(buf),
401 "%s unreachable - need to frag",
402 GET_IPADDR_STRING(dp->icmp_ip.ip_dst));
403 }
404 }
405 break;
406
407 case ICMP_UNREACH_SRCFAIL:
408 (void)snprintf(buf, sizeof(buf),
409 "%s unreachable - source route failed",
410 GET_IPADDR_STRING(dp->icmp_ip.ip_dst));
411 break;
412
413 case ICMP_UNREACH_NET_UNKNOWN:
414 (void)snprintf(buf, sizeof(buf),
415 "net %s unreachable - unknown",
416 GET_IPADDR_STRING(dp->icmp_ip.ip_dst));
417 break;
418
419 case ICMP_UNREACH_HOST_UNKNOWN:
420 (void)snprintf(buf, sizeof(buf),
421 "host %s unreachable - unknown",
422 GET_IPADDR_STRING(dp->icmp_ip.ip_dst));
423 break;
424
425 case ICMP_UNREACH_ISOLATED:
426 (void)snprintf(buf, sizeof(buf),
427 "%s unreachable - source host isolated",
428 GET_IPADDR_STRING(dp->icmp_ip.ip_dst));
429 break;
430
431 case ICMP_UNREACH_NET_PROHIB:
432 (void)snprintf(buf, sizeof(buf),
433 "net %s unreachable - admin prohibited",
434 GET_IPADDR_STRING(dp->icmp_ip.ip_dst));
435 break;
436
437 case ICMP_UNREACH_HOST_PROHIB:
438 (void)snprintf(buf, sizeof(buf),
439 "host %s unreachable - admin prohibited",
440 GET_IPADDR_STRING(dp->icmp_ip.ip_dst));
441 break;
442
443 case ICMP_UNREACH_TOSNET:
444 (void)snprintf(buf, sizeof(buf),
445 "net %s unreachable - tos prohibited",
446 GET_IPADDR_STRING(dp->icmp_ip.ip_dst));
447 break;
448
449 case ICMP_UNREACH_TOSHOST:
450 (void)snprintf(buf, sizeof(buf),
451 "host %s unreachable - tos prohibited",
452 GET_IPADDR_STRING(dp->icmp_ip.ip_dst));
453 break;
454
455 case ICMP_UNREACH_FILTER_PROHIB:
456 (void)snprintf(buf, sizeof(buf),
457 "host %s unreachable - admin prohibited filter",
458 GET_IPADDR_STRING(dp->icmp_ip.ip_dst));
459 break;
460
461 case ICMP_UNREACH_HOST_PRECEDENCE:
462 (void)snprintf(buf, sizeof(buf),
463 "host %s unreachable - host precedence violation",
464 GET_IPADDR_STRING(dp->icmp_ip.ip_dst));
465 break;
466
467 case ICMP_UNREACH_PRECEDENCE_CUTOFF:
468 (void)snprintf(buf, sizeof(buf),
469 "host %s unreachable - precedence cutoff",
470 GET_IPADDR_STRING(dp->icmp_ip.ip_dst));
471 break;
472
473 default:
474 (void)snprintf(buf, sizeof(buf),
475 "%s unreachable - #%u",
476 GET_IPADDR_STRING(dp->icmp_ip.ip_dst),
477 icmp_code);
478 break;
479 }
480 break;
481
482 case ICMP_REDIRECT:
483 switch (icmp_code) {
484
485 case ICMP_REDIRECT_NET:
486 (void)snprintf(buf, sizeof(buf),
487 "redirect %s to net %s",
488 GET_IPADDR_STRING(dp->icmp_ip.ip_dst),
489 GET_IPADDR_STRING(dp->icmp_gwaddr));
490 break;
491
492 case ICMP_REDIRECT_HOST:
493 (void)snprintf(buf, sizeof(buf),
494 "redirect %s to host %s",
495 GET_IPADDR_STRING(dp->icmp_ip.ip_dst),
496 GET_IPADDR_STRING(dp->icmp_gwaddr));
497 break;
498
499 case ICMP_REDIRECT_TOSNET:
500 (void)snprintf(buf, sizeof(buf),
501 "redirect-tos %s to net %s",
502 GET_IPADDR_STRING(dp->icmp_ip.ip_dst),
503 GET_IPADDR_STRING(dp->icmp_gwaddr));
504 break;
505
506 case ICMP_REDIRECT_TOSHOST:
507 (void)snprintf(buf, sizeof(buf),
508 "redirect-tos %s to host %s",
509 GET_IPADDR_STRING(dp->icmp_ip.ip_dst),
510 GET_IPADDR_STRING(dp->icmp_gwaddr));
511 break;
512
513 default:
514 (void)snprintf(buf, sizeof(buf),
515 "redirect-#%u %s to %s", icmp_code,
516 GET_IPADDR_STRING(dp->icmp_ip.ip_dst),
517 GET_IPADDR_STRING(dp->icmp_gwaddr));
518 break;
519 }
520 break;
521
522 case ICMP_ROUTERADVERT:
523 {
524 const struct ih_rdiscovery *ihp;
525 const struct id_rdiscovery *idp;
526 u_int lifetime, num, size;
527
528 (void)snprintf(buf, sizeof(buf), "router advertisement");
529 cp = buf + strlen(buf);
530
531 ihp = (const struct ih_rdiscovery *)&dp->icmp_void;
532 ND_TCHECK_SIZE(ihp);
533 (void)strncpy(cp, " lifetime ", sizeof(buf) - (cp - buf));
534 cp = buf + strlen(buf);
535 lifetime = GET_BE_U_2(ihp->ird_lifetime);
536 if (lifetime < 60) {
537 (void)snprintf(cp, sizeof(buf) - (cp - buf), "%u",
538 lifetime);
539 } else if (lifetime < 60 * 60) {
540 (void)snprintf(cp, sizeof(buf) - (cp - buf), "%u:%02u",
541 lifetime / 60, lifetime % 60);
542 } else {
543 (void)snprintf(cp, sizeof(buf) - (cp - buf),
544 "%u:%02u:%02u",
545 lifetime / 3600,
546 (lifetime % 3600) / 60,
547 lifetime % 60);
548 }
549 cp = buf + strlen(buf);
550
551 num = GET_U_1(ihp->ird_addrnum);
552 (void)snprintf(cp, sizeof(buf) - (cp - buf), " %u:", num);
553 cp = buf + strlen(buf);
554
555 size = GET_U_1(ihp->ird_addrsiz);
556 if (size != 2) {
557 (void)snprintf(cp, sizeof(buf) - (cp - buf),
558 " [size %u]", size);
559 break;
560 }
561 idp = (const struct id_rdiscovery *)&dp->icmp_data;
562 while (num > 0) {
563 ND_TCHECK_SIZE(idp);
564 (void)snprintf(cp, sizeof(buf) - (cp - buf), " {%s %u}",
565 GET_IPADDR_STRING(idp->ird_addr),
566 GET_BE_U_4(idp->ird_pref));
567 cp = buf + strlen(buf);
568 ++idp;
569 num--;
570 }
571 }
572 break;
573
574 case ICMP_TIMXCEED:
575 ND_TCHECK_4(dp->icmp_ip.ip_dst);
576 switch (icmp_code) {
577
578 case ICMP_TIMXCEED_INTRANS:
579 str = "time exceeded in-transit";
580 break;
581
582 case ICMP_TIMXCEED_REASS:
583 str = "ip reassembly time exceeded";
584 break;
585
586 default:
587 (void)snprintf(buf, sizeof(buf), "time exceeded-#%u",
588 icmp_code);
589 break;
590 }
591 break;
592
593 case ICMP_PARAMPROB:
594 if (icmp_code)
595 (void)snprintf(buf, sizeof(buf),
596 "parameter problem - code %u", icmp_code);
597 else {
598 ND_TCHECK_1(dp->icmp_pptr);
599 (void)snprintf(buf, sizeof(buf),
600 "parameter problem - octet %u",
601 GET_U_1(dp->icmp_pptr));
602 }
603 break;
604
605 case ICMP_MASKREPLY:
606 (void)snprintf(buf, sizeof(buf), "address mask is 0x%08x",
607 GET_BE_U_4(dp->icmp_mask));
608 break;
609
610 case ICMP_TSTAMP:
611 ND_TCHECK_2(dp->icmp_seq);
612 (void)snprintf(buf, sizeof(buf),
613 "time stamp query id %u seq %u",
614 GET_BE_U_2(dp->icmp_id),
615 GET_BE_U_2(dp->icmp_seq));
616 break;
617
618 case ICMP_TSTAMPREPLY:
619 ND_TCHECK_4(dp->icmp_ttime);
620 (void)snprintf(buf, sizeof(buf),
621 "time stamp reply id %u seq %u: org %s",
622 GET_BE_U_2(dp->icmp_id),
623 GET_BE_U_2(dp->icmp_seq),
624 icmp_tstamp_print(GET_BE_U_4(dp->icmp_otime)));
625
626 (void)snprintf(buf+strlen(buf),sizeof(buf)-strlen(buf),", recv %s",
627 icmp_tstamp_print(GET_BE_U_4(dp->icmp_rtime)));
628 (void)snprintf(buf+strlen(buf),sizeof(buf)-strlen(buf),", xmit %s",
629 icmp_tstamp_print(GET_BE_U_4(dp->icmp_ttime)));
630 break;
631
632 default:
633 str = tok2str(icmp2str, "type-#%u", icmp_type);
634 break;
635 }
636 ND_PRINT("ICMP %s, length %u", str, plen);
637 if (ndo->ndo_vflag && !fragmented) { /* don't attempt checksumming if this is a frag */
638 if (ND_TTEST_LEN(bp, plen)) {
639 uint16_t sum;
640
641 vec[0].ptr = (const uint8_t *)(const void *)dp;
642 vec[0].len = plen;
643 sum = in_cksum(vec, 1);
644 if (sum != 0) {
645 uint16_t icmp_sum = GET_BE_U_2(dp->icmp_cksum);
646 ND_PRINT(" (wrong icmp cksum %x (->%x)!)",
647 icmp_sum,
648 in_cksum_shouldbe(icmp_sum, sum));
649 }
650 }
651 }
652
653 /*
654 * print the remnants of the IP packet.
655 * save the snaplength as this may get overidden in the IP printer.
656 */
657 if (ndo->ndo_vflag >= 1 && ICMP_ERRTYPE(icmp_type)) {
658 bp += 8;
659 ND_PRINT("\n\t");
660 ip = (const struct ip *)bp;
661 snapend_save = ndo->ndo_snapend;
662 ip_print(ndo, bp, GET_BE_U_2(ip->ip_len));
663 ndo->ndo_snapend = snapend_save;
664 }
665
666 /* ndo_protocol reassignment after ip_print() call */
667 ndo->ndo_protocol = "icmp";
668
669 /*
670 * Attempt to decode the MPLS extensions only for some ICMP types.
671 */
672 if (ndo->ndo_vflag >= 1 && plen > ICMP_EXTD_MINLEN && ICMP_MPLS_EXT_TYPE(icmp_type)) {
673
674 ND_TCHECK_SIZE(ext_dp);
675
676 /*
677 * Check first if the mpls extension header shows a non-zero length.
678 * If the length field is not set then silently verify the checksum
679 * to check if an extension header is present. This is expedient,
680 * however not all implementations set the length field proper.
681 */
682 if (GET_U_1(ext_dp->icmp_length) == 0 &&
683 ND_TTEST_LEN(ext_dp->icmp_ext_version_res, plen - ICMP_EXTD_MINLEN)) {
684 vec[0].ptr = (const uint8_t *)(const void *)&ext_dp->icmp_ext_version_res;
685 vec[0].len = plen - ICMP_EXTD_MINLEN;
686 if (in_cksum(vec, 1)) {
687 return;
688 }
689 }
690
691 ND_PRINT("\n\tMPLS extension v%u",
692 ICMP_MPLS_EXT_EXTRACT_VERSION(*(ext_dp->icmp_ext_version_res)));
693
694 /*
695 * Sanity checking of the header.
696 */
697 if (ICMP_MPLS_EXT_EXTRACT_VERSION(*(ext_dp->icmp_ext_version_res)) !=
698 ICMP_MPLS_EXT_VERSION) {
699 ND_PRINT(" packet not supported");
700 return;
701 }
702
703 hlen = plen - ICMP_EXTD_MINLEN;
704 if (ND_TTEST_LEN(ext_dp->icmp_ext_version_res, hlen)) {
705 vec[0].ptr = (const uint8_t *)(const void *)&ext_dp->icmp_ext_version_res;
706 vec[0].len = hlen;
707 ND_PRINT(", checksum 0x%04x (%scorrect), length %u",
708 GET_BE_U_2(ext_dp->icmp_ext_checksum),
709 in_cksum(vec, 1) ? "in" : "",
710 hlen);
711 }
712
713 hlen -= 4; /* subtract common header size */
714 obj_tptr = (const uint8_t *)ext_dp->icmp_ext_data;
715
716 while (hlen > sizeof(struct icmp_mpls_ext_object_header_t)) {
717
718 icmp_mpls_ext_object_header = (const struct icmp_mpls_ext_object_header_t *)obj_tptr;
719 ND_TCHECK_SIZE(icmp_mpls_ext_object_header);
720 obj_tlen = GET_BE_U_2(icmp_mpls_ext_object_header->length);
721 obj_class_num = GET_U_1(icmp_mpls_ext_object_header->class_num);
722 obj_ctype = GET_U_1(icmp_mpls_ext_object_header->ctype);
723 obj_tptr += sizeof(struct icmp_mpls_ext_object_header_t);
724
725 ND_PRINT("\n\t %s Object (%u), Class-Type: %u, length %u",
726 tok2str(icmp_mpls_ext_obj_values,"unknown",obj_class_num),
727 obj_class_num,
728 obj_ctype,
729 obj_tlen);
730
731 hlen-=sizeof(struct icmp_mpls_ext_object_header_t); /* length field includes tlv header */
732
733 /* infinite loop protection */
734 if ((obj_class_num == 0) ||
735 (obj_tlen < sizeof(struct icmp_mpls_ext_object_header_t))) {
736 return;
737 }
738 obj_tlen-=sizeof(struct icmp_mpls_ext_object_header_t);
739
740 switch (obj_class_num) {
741 case 1:
742 switch(obj_ctype) {
743 case 1:
744 raw_label = GET_BE_U_4(obj_tptr);
745 ND_PRINT("\n\t label %u, exp %u", MPLS_LABEL(raw_label), MPLS_EXP(raw_label));
746 if (MPLS_STACK(raw_label))
747 ND_PRINT(", [S]");
748 ND_PRINT(", ttl %u", MPLS_TTL(raw_label));
749 break;
750 default:
751 print_unknown_data(ndo, obj_tptr, "\n\t ", obj_tlen);
752 }
753 break;
754
755 /*
756 * FIXME those are the defined objects that lack a decoder
757 * you are welcome to contribute code ;-)
758 */
759 case 2:
760 default:
761 print_unknown_data(ndo, obj_tptr, "\n\t ", obj_tlen);
762 break;
763 }
764 if (hlen < obj_tlen)
765 break;
766 hlen -= obj_tlen;
767 obj_tptr += obj_tlen;
768 }
769 }
770
771 return;
772 trunc:
773 nd_print_trunc(ndo);
774 }
[mirror] the TCPdump network dissector