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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 #define ND_LONGJMP_FROM_TCHECK
34 #include "netdissect.h"
35 #include "addrtoname.h"
36 #include "extract.h"
37
38 #include "ip.h"
39 #include "udp.h"
40 #include "ipproto.h"
41 #include "mpls.h"
42
43 /*
44 * Interface Control Message Protocol Definitions.
45 * Per RFC 792, September 1981.
46 */
47
48 /*
49 * Structure of an icmp header.
50 */
51 struct icmp {
52 nd_uint8_t icmp_type; /* type of message, see below */
53 nd_uint8_t icmp_code; /* type sub code */
54 nd_uint16_t icmp_cksum; /* ones complement cksum of struct */
55 union {
56 nd_uint8_t ih_pptr; /* ICMP_PARAMPROB */
57 nd_ipv4 ih_gwaddr; /* ICMP_REDIRECT */
58 struct ih_idseq {
59 nd_uint16_t icd_id;
60 nd_uint16_t icd_seq;
61 } ih_idseq;
62 nd_uint32_t ih_void;
63 } icmp_hun;
64 #define icmp_pptr icmp_hun.ih_pptr
65 #define icmp_gwaddr icmp_hun.ih_gwaddr
66 #define icmp_id icmp_hun.ih_idseq.icd_id
67 #define icmp_seq icmp_hun.ih_idseq.icd_seq
68 #define icmp_void icmp_hun.ih_void
69 union {
70 struct id_ts {
71 nd_uint32_t its_otime;
72 nd_uint32_t its_rtime;
73 nd_uint32_t its_ttime;
74 } id_ts;
75 struct id_ip {
76 struct ip idi_ip;
77 /* options and then 64 bits of data */
78 } id_ip;
79 nd_uint32_t id_mask;
80 nd_byte id_data[1];
81 } icmp_dun;
82 #define icmp_otime icmp_dun.id_ts.its_otime
83 #define icmp_rtime icmp_dun.id_ts.its_rtime
84 #define icmp_ttime icmp_dun.id_ts.its_ttime
85 #define icmp_ip icmp_dun.id_ip.idi_ip
86 #define icmp_mask icmp_dun.id_mask
87 #define icmp_data icmp_dun.id_data
88 };
89
90 /*
91 * Lower bounds on packet lengths for various types.
92 * For the error advice packets must first insure that the
93 * packet is large enough to contain the returned ip header.
94 * Only then can we do the check to see if 64 bits of packet
95 * data have been returned, since we need to check the returned
96 * ip header length.
97 */
98 #define ICMP_MINLEN 8 /* abs minimum */
99 #define ICMP_EXTD_MINLEN (156 - sizeof (struct ip)) /* draft-bonica-internet-icmp-08 */
100 #define ICMP_TSLEN (8 + 3 * sizeof (uint32_t)) /* timestamp */
101 #define ICMP_MASKLEN 12 /* address mask */
102 #define ICMP_ADVLENMIN (8 + sizeof (struct ip) + 8) /* min */
103 #define ICMP_ADVLEN(p) (8 + (IP_HL(&(p)->icmp_ip) << 2) + 8)
104 /* N.B.: must separately check that ip_hl >= 5 */
105
106 /*
107 * Definition of type and code field values.
108 */
109 #define ICMP_ECHOREPLY 0 /* echo reply */
110 #define ICMP_UNREACH 3 /* dest unreachable, codes: */
111 #define ICMP_UNREACH_NET 0 /* bad net */
112 #define ICMP_UNREACH_HOST 1 /* bad host */
113 #define ICMP_UNREACH_PROTOCOL 2 /* bad protocol */
114 #define ICMP_UNREACH_PORT 3 /* bad port */
115 #define ICMP_UNREACH_NEEDFRAG 4 /* IP_DF caused drop */
116 #define ICMP_UNREACH_SRCFAIL 5 /* src route failed */
117 #define ICMP_UNREACH_NET_UNKNOWN 6 /* unknown net */
118 #define ICMP_UNREACH_HOST_UNKNOWN 7 /* unknown host */
119 #define ICMP_UNREACH_ISOLATED 8 /* src host isolated */
120 #define ICMP_UNREACH_NET_PROHIB 9 /* prohibited access */
121 #define ICMP_UNREACH_HOST_PROHIB 10 /* ditto */
122 #define ICMP_UNREACH_TOSNET 11 /* bad tos for net */
123 #define ICMP_UNREACH_TOSHOST 12 /* bad tos for host */
124 #define ICMP_SOURCEQUENCH 4 /* packet lost, slow down */
125 #define ICMP_REDIRECT 5 /* shorter route, codes: */
126 #define ICMP_REDIRECT_NET 0 /* for network */
127 #define ICMP_REDIRECT_HOST 1 /* for host */
128 #define ICMP_REDIRECT_TOSNET 2 /* for tos and net */
129 #define ICMP_REDIRECT_TOSHOST 3 /* for tos and host */
130 #define ICMP_ECHO 8 /* echo service */
131 #define ICMP_ROUTERADVERT 9 /* router advertisement */
132 #define ICMP_ROUTERSOLICIT 10 /* router solicitation */
133 #define ICMP_TIMXCEED 11 /* time exceeded, code: */
134 #define ICMP_TIMXCEED_INTRANS 0 /* ttl==0 in transit */
135 #define ICMP_TIMXCEED_REASS 1 /* ttl==0 in reass */
136 #define ICMP_PARAMPROB 12 /* ip header bad */
137 #define ICMP_PARAMPROB_OPTABSENT 1 /* req. opt. absent */
138 #define ICMP_TSTAMP 13 /* timestamp request */
139 #define ICMP_TSTAMPREPLY 14 /* timestamp reply */
140 #define ICMP_IREQ 15 /* information request */
141 #define ICMP_IREQREPLY 16 /* information reply */
142 #define ICMP_MASKREQ 17 /* address mask request */
143 #define ICMP_MASKREPLY 18 /* address mask reply */
144
145 #define ICMP_MAXTYPE 18
146
147 #define ICMP_ERRTYPE(type) \
148 ((type) == ICMP_UNREACH || (type) == ICMP_SOURCEQUENCH || \
149 (type) == ICMP_REDIRECT || (type) == ICMP_TIMXCEED || \
150 (type) == ICMP_PARAMPROB)
151 #define ICMP_MULTIPART_EXT_TYPE(type) \
152 ((type) == ICMP_UNREACH || \
153 (type) == ICMP_TIMXCEED || \
154 (type) == ICMP_PARAMPROB)
155 /* rfc1700 */
156 #ifndef ICMP_UNREACH_NET_UNKNOWN
157 #define ICMP_UNREACH_NET_UNKNOWN 6 /* destination net unknown */
158 #endif
159 #ifndef ICMP_UNREACH_HOST_UNKNOWN
160 #define ICMP_UNREACH_HOST_UNKNOWN 7 /* destination host unknown */
161 #endif
162 #ifndef ICMP_UNREACH_ISOLATED
163 #define ICMP_UNREACH_ISOLATED 8 /* source host isolated */
164 #endif
165 #ifndef ICMP_UNREACH_NET_PROHIB
166 #define ICMP_UNREACH_NET_PROHIB 9 /* admin prohibited net */
167 #endif
168 #ifndef ICMP_UNREACH_HOST_PROHIB
169 #define ICMP_UNREACH_HOST_PROHIB 10 /* admin prohibited host */
170 #endif
171 #ifndef ICMP_UNREACH_TOSNET
172 #define ICMP_UNREACH_TOSNET 11 /* tos prohibited net */
173 #endif
174 #ifndef ICMP_UNREACH_TOSHOST
175 #define ICMP_UNREACH_TOSHOST 12 /* tos prohibited host */
176 #endif
177
178 /* rfc1716 */
179 #ifndef ICMP_UNREACH_FILTER_PROHIB
180 #define ICMP_UNREACH_FILTER_PROHIB 13 /* admin prohibited filter */
181 #endif
182 #ifndef ICMP_UNREACH_HOST_PRECEDENCE
183 #define ICMP_UNREACH_HOST_PRECEDENCE 14 /* host precedence violation */
184 #endif
185 #ifndef ICMP_UNREACH_PRECEDENCE_CUTOFF
186 #define ICMP_UNREACH_PRECEDENCE_CUTOFF 15 /* precedence cutoff */
187 #endif
188
189 /* Most of the icmp types */
190 static const struct tok icmp2str[] = {
191 { ICMP_ECHOREPLY, "echo reply" },
192 { ICMP_SOURCEQUENCH, "source quench" },
193 { ICMP_ECHO, "echo request" },
194 { ICMP_ROUTERSOLICIT, "router solicitation" },
195 { ICMP_TSTAMP, "time stamp request" },
196 { ICMP_TSTAMPREPLY, "time stamp reply" },
197 { ICMP_IREQ, "information request" },
198 { ICMP_IREQREPLY, "information reply" },
199 { ICMP_MASKREQ, "address mask request" },
200 { 0, NULL }
201 };
202
203 /* rfc1191 */
204 struct mtu_discovery {
205 nd_uint16_t unused;
206 nd_uint16_t nexthopmtu;
207 };
208
209 /* rfc1256 */
210 struct ih_rdiscovery {
211 nd_uint8_t ird_addrnum;
212 nd_uint8_t ird_addrsiz;
213 nd_uint16_t ird_lifetime;
214 };
215
216 struct id_rdiscovery {
217 nd_uint32_t ird_addr;
218 nd_uint32_t ird_pref;
219 };
220
221 /*
222 * RFC 4884 - Extended ICMP to Support Multi-Part Messages
223 *
224 * This is a general extension mechanism, based on the mechanism
225 * in draft-bonica-icmp-mpls-02 ICMP Extensions for MultiProtocol
226 * Label Switching.
227 *
228 * The Destination Unreachable, Time Exceeded
229 * and Parameter Problem messages are slightly changed as per
230 * the above RFC. A new Length field gets added to give
231 * the caller an idea about the length of the piggybacked
232 * IP packet before the extension header starts.
233 *
234 * The Length field represents length of the padded "original datagram"
235 * field measured in 32-bit words.
236 *
237 * 0 1 2 3
238 * 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
239 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
240 * | Type | Code | Checksum |
241 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
242 * | unused | Length | unused |
243 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
244 * | Internet Header + leading octets of original datagram |
245 * | |
246 * | // |
247 * | |
248 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
249 */
250
251 struct icmp_ext_t {
252 nd_uint8_t icmp_type;
253 nd_uint8_t icmp_code;
254 nd_uint16_t icmp_checksum;
255 nd_byte icmp_reserved;
256 nd_uint8_t icmp_length;
257 nd_byte icmp_reserved2[2];
258 nd_byte icmp_ext_legacy_header[128]; /* extension header starts 128 bytes after ICMP header */
259 nd_byte icmp_ext_version_res[2];
260 nd_uint16_t icmp_ext_checksum;
261 nd_byte icmp_ext_data[1];
262 };
263
264 /*
265 * Extract version from the first octet of icmp_ext_version_res.
266 */
267 #define ICMP_EXT_EXTRACT_VERSION(x) (((x)&0xf0)>>4)
268
269 /*
270 * Current version.
271 */
272 #define ICMP_EXT_VERSION 2
273
274 /*
275 * Extension object class numbers.
276 *
277 * Class 1 dates back to draft-bonica-icmp-mpls-02.
278 *
279 * Class 2 was used for an "Extended Payload Object Class", which
280 * contained bytes of the payload beyond the first 128 bytes, in
281 * draft-bonica-icmp-mpls-02; it was reassigned to an "Interface
282 * Information Object" in RFC 5837.
283 */
284
285 /* rfc4950 */
286 #define MPLS_STACK_ENTRY_OBJECT_CLASS 1
287 /* rfc5837 */
288 #define INTERFACE_INFORMATION_OBJECT_CLASS 2
289
290 struct icmp_multipart_ext_object_header_t {
291 nd_uint16_t length;
292 nd_uint8_t class_num;
293 nd_uint8_t ctype;
294 };
295
296 static const struct tok icmp_multipart_ext_obj_values[] = {
297 { 1, "MPLS Stack Entry Object" },
298 { 2, "Interface Information Object" },
299 { 0, NULL}
300 };
301
302 /* rfc5837 */
303 static const struct tok icmp_interface_information_role_values[] = {
304 { 0, "Incoming IP Interface"},
305 { 1, "Sub-IP Component of Incoming IP Interface"},
306 { 2, "Outgoing IP Interface"},
307 { 3, "IP Next hop"},
308 { 0, NULL }
309 };
310
311 /*
312 Interface IP Address Sub-Object
313 0 31
314 +-------+-------+-------+-------+
315 | AFI | Reserved |
316 +-------+-------+-------+-------+
317 | IP Address ....
318 */
319 struct icmp_interface_information_ipaddr_subobject_t {
320 nd_uint16_t afi;
321 nd_uint16_t reserved;
322 nd_uint32_t ip_addr;
323 };
324
325 /*
326 Interface Name Sub-Object
327 octet 0 1 63
328 +--------+-----------................-----------------+
329 | length | interface name octets 1-63 |
330 +--------+-----------................-----------------+
331 */
332 struct icmp_interface_information_ifname_subobject_t {
333 nd_uint8_t length;
334 nd_byte if_name[63];
335 };
336
337 /* prototypes */
338 const char *icmp_tstamp_print(u_int);
339
340 /* print the milliseconds since midnight UTC */
341 const char *
342 icmp_tstamp_print(u_int tstamp)
343 {
344 u_int msec,sec,min,hrs;
345
346 static char buf[64];
347
348 msec = tstamp % 1000;
349 sec = tstamp / 1000;
350 min = sec / 60; sec -= min * 60;
351 hrs = min / 60; min -= hrs * 60;
352 snprintf(buf, sizeof(buf), "%02u:%02u:%02u.%03u",hrs,min,sec,msec);
353 return buf;
354 }
355
356 void
357 icmp_print(netdissect_options *ndo, const u_char *bp, u_int plen,
358 int fragmented)
359 {
360 const struct icmp *dp;
361 uint8_t icmp_type, icmp_code;
362 const struct icmp_ext_t *ext_dp;
363 const char *str;
364 const uint8_t *obj_tptr;
365 u_int hlen;
366 char buf[MAXHOSTNAMELEN + 100];
367 struct cksum_vec vec[1];
368
369 ndo->ndo_protocol = "icmp";
370 dp = (const struct icmp *)bp;
371 ext_dp = (const struct icmp_ext_t *)bp;
372 str = buf;
373
374 icmp_type = GET_U_1(dp->icmp_type);
375 icmp_code = GET_U_1(dp->icmp_code);
376 switch (icmp_type) {
377
378 case ICMP_ECHO:
379 case ICMP_ECHOREPLY:
380 (void)snprintf(buf, sizeof(buf), "echo %s, id %u, seq %u",
381 icmp_type == ICMP_ECHO ?
382 "request" : "reply",
383 GET_BE_U_2(dp->icmp_id),
384 GET_BE_U_2(dp->icmp_seq));
385 break;
386
387 case ICMP_UNREACH:
388 switch (icmp_code) {
389
390 case ICMP_UNREACH_NET:
391 (void)snprintf(buf, sizeof(buf),
392 "net %s unreachable",
393 GET_IPADDR_STRING(dp->icmp_ip.ip_dst));
394 break;
395
396 case ICMP_UNREACH_HOST:
397 (void)snprintf(buf, sizeof(buf),
398 "host %s unreachable",
399 GET_IPADDR_STRING(dp->icmp_ip.ip_dst));
400 break;
401
402 case ICMP_UNREACH_PROTOCOL:
403 (void)snprintf(buf, sizeof(buf),
404 "%s protocol %u unreachable",
405 GET_IPADDR_STRING(dp->icmp_ip.ip_dst),
406 GET_U_1(dp->icmp_ip.ip_p));
407 break;
408
409 case ICMP_UNREACH_PORT:
410 {
411 const struct ip *oip;
412 const struct udphdr *ouh;
413 uint8_t ip_proto;
414 uint16_t dport;
415
416 oip = &dp->icmp_ip;
417 hlen = IP_HL(oip) * 4;
418 ouh = (const struct udphdr *)(((const u_char *)oip) + hlen);
419 dport = GET_BE_U_2(ouh->uh_dport);
420 ip_proto = GET_U_1(oip->ip_p);
421 switch (ip_proto) {
422
423 case IPPROTO_TCP:
424 (void)snprintf(buf, sizeof(buf),
425 "%s tcp port %s unreachable",
426 GET_IPADDR_STRING(oip->ip_dst),
427 tcpport_string(ndo, dport));
428 break;
429
430 case IPPROTO_UDP:
431 (void)snprintf(buf, sizeof(buf),
432 "%s udp port %s unreachable",
433 GET_IPADDR_STRING(oip->ip_dst),
434 udpport_string(ndo, dport));
435 break;
436
437 default:
438 (void)snprintf(buf, sizeof(buf),
439 "%s protocol %u port %u unreachable",
440 GET_IPADDR_STRING(oip->ip_dst),
441 ip_proto, dport);
442 break;
443 }
444 break;
445 }
446
447 case ICMP_UNREACH_NEEDFRAG:
448 {
449 const struct mtu_discovery *mp;
450 u_int mtu;
451
452 mp = (const struct mtu_discovery *)(const u_char *)&dp->icmp_void;
453 mtu = GET_BE_U_2(mp->nexthopmtu);
454 if (mtu) {
455 (void)snprintf(buf, sizeof(buf),
456 "%s unreachable - need to frag (mtu %u)",
457 GET_IPADDR_STRING(dp->icmp_ip.ip_dst), mtu);
458 } else {
459 (void)snprintf(buf, sizeof(buf),
460 "%s unreachable - need to frag",
461 GET_IPADDR_STRING(dp->icmp_ip.ip_dst));
462 }
463 }
464 break;
465
466 case ICMP_UNREACH_SRCFAIL:
467 (void)snprintf(buf, sizeof(buf),
468 "%s unreachable - source route failed",
469 GET_IPADDR_STRING(dp->icmp_ip.ip_dst));
470 break;
471
472 case ICMP_UNREACH_NET_UNKNOWN:
473 (void)snprintf(buf, sizeof(buf),
474 "net %s unreachable - unknown",
475 GET_IPADDR_STRING(dp->icmp_ip.ip_dst));
476 break;
477
478 case ICMP_UNREACH_HOST_UNKNOWN:
479 (void)snprintf(buf, sizeof(buf),
480 "host %s unreachable - unknown",
481 GET_IPADDR_STRING(dp->icmp_ip.ip_dst));
482 break;
483
484 case ICMP_UNREACH_ISOLATED:
485 (void)snprintf(buf, sizeof(buf),
486 "%s unreachable - source host isolated",
487 GET_IPADDR_STRING(dp->icmp_ip.ip_dst));
488 break;
489
490 case ICMP_UNREACH_NET_PROHIB:
491 (void)snprintf(buf, sizeof(buf),
492 "net %s unreachable - admin prohibited",
493 GET_IPADDR_STRING(dp->icmp_ip.ip_dst));
494 break;
495
496 case ICMP_UNREACH_HOST_PROHIB:
497 (void)snprintf(buf, sizeof(buf),
498 "host %s unreachable - admin prohibited",
499 GET_IPADDR_STRING(dp->icmp_ip.ip_dst));
500 break;
501
502 case ICMP_UNREACH_TOSNET:
503 (void)snprintf(buf, sizeof(buf),
504 "net %s unreachable - tos prohibited",
505 GET_IPADDR_STRING(dp->icmp_ip.ip_dst));
506 break;
507
508 case ICMP_UNREACH_TOSHOST:
509 (void)snprintf(buf, sizeof(buf),
510 "host %s unreachable - tos prohibited",
511 GET_IPADDR_STRING(dp->icmp_ip.ip_dst));
512 break;
513
514 case ICMP_UNREACH_FILTER_PROHIB:
515 (void)snprintf(buf, sizeof(buf),
516 "host %s unreachable - admin prohibited filter",
517 GET_IPADDR_STRING(dp->icmp_ip.ip_dst));
518 break;
519
520 case ICMP_UNREACH_HOST_PRECEDENCE:
521 (void)snprintf(buf, sizeof(buf),
522 "host %s unreachable - host precedence violation",
523 GET_IPADDR_STRING(dp->icmp_ip.ip_dst));
524 break;
525
526 case ICMP_UNREACH_PRECEDENCE_CUTOFF:
527 (void)snprintf(buf, sizeof(buf),
528 "host %s unreachable - precedence cutoff",
529 GET_IPADDR_STRING(dp->icmp_ip.ip_dst));
530 break;
531
532 default:
533 (void)snprintf(buf, sizeof(buf),
534 "%s unreachable - #%u",
535 GET_IPADDR_STRING(dp->icmp_ip.ip_dst),
536 icmp_code);
537 break;
538 }
539 break;
540
541 case ICMP_REDIRECT:
542 switch (icmp_code) {
543
544 case ICMP_REDIRECT_NET:
545 (void)snprintf(buf, sizeof(buf),
546 "redirect %s to net %s",
547 GET_IPADDR_STRING(dp->icmp_ip.ip_dst),
548 GET_IPADDR_STRING(dp->icmp_gwaddr));
549 break;
550
551 case ICMP_REDIRECT_HOST:
552 (void)snprintf(buf, sizeof(buf),
553 "redirect %s to host %s",
554 GET_IPADDR_STRING(dp->icmp_ip.ip_dst),
555 GET_IPADDR_STRING(dp->icmp_gwaddr));
556 break;
557
558 case ICMP_REDIRECT_TOSNET:
559 (void)snprintf(buf, sizeof(buf),
560 "redirect-tos %s to net %s",
561 GET_IPADDR_STRING(dp->icmp_ip.ip_dst),
562 GET_IPADDR_STRING(dp->icmp_gwaddr));
563 break;
564
565 case ICMP_REDIRECT_TOSHOST:
566 (void)snprintf(buf, sizeof(buf),
567 "redirect-tos %s to host %s",
568 GET_IPADDR_STRING(dp->icmp_ip.ip_dst),
569 GET_IPADDR_STRING(dp->icmp_gwaddr));
570 break;
571
572 default:
573 (void)snprintf(buf, sizeof(buf),
574 "redirect-#%u %s to %s", icmp_code,
575 GET_IPADDR_STRING(dp->icmp_ip.ip_dst),
576 GET_IPADDR_STRING(dp->icmp_gwaddr));
577 break;
578 }
579 break;
580
581 case ICMP_ROUTERADVERT:
582 {
583 char *cp;
584 const struct ih_rdiscovery *ihp;
585 const struct id_rdiscovery *idp;
586 u_int lifetime, num, size;
587
588 (void)snprintf(buf, sizeof(buf), "router advertisement");
589 cp = buf + strlen(buf);
590
591 ihp = (const struct ih_rdiscovery *)&dp->icmp_void;
592 (void)strncpy(cp, " lifetime ", sizeof(buf) - (cp - buf));
593 cp = buf + strlen(buf);
594 lifetime = GET_BE_U_2(ihp->ird_lifetime);
595 if (lifetime < 60) {
596 (void)snprintf(cp, sizeof(buf) - (cp - buf), "%u",
597 lifetime);
598 } else if (lifetime < 60 * 60) {
599 (void)snprintf(cp, sizeof(buf) - (cp - buf), "%u:%02u",
600 lifetime / 60, lifetime % 60);
601 } else {
602 (void)snprintf(cp, sizeof(buf) - (cp - buf),
603 "%u:%02u:%02u",
604 lifetime / 3600,
605 (lifetime % 3600) / 60,
606 lifetime % 60);
607 }
608 cp = buf + strlen(buf);
609
610 num = GET_U_1(ihp->ird_addrnum);
611 (void)snprintf(cp, sizeof(buf) - (cp - buf), " %u:", num);
612 cp = buf + strlen(buf);
613
614 size = GET_U_1(ihp->ird_addrsiz);
615 if (size != 2) {
616 (void)snprintf(cp, sizeof(buf) - (cp - buf),
617 " [size %u]", size);
618 break;
619 }
620 idp = (const struct id_rdiscovery *)&dp->icmp_data;
621 while (num > 0) {
622 (void)snprintf(cp, sizeof(buf) - (cp - buf), " {%s %u}",
623 GET_IPADDR_STRING(idp->ird_addr),
624 GET_BE_U_4(idp->ird_pref));
625 cp = buf + strlen(buf);
626 ++idp;
627 num--;
628 }
629 }
630 break;
631
632 case ICMP_TIMXCEED:
633 ND_TCHECK_4(dp->icmp_ip.ip_dst);
634 switch (icmp_code) {
635
636 case ICMP_TIMXCEED_INTRANS:
637 str = "time exceeded in-transit";
638 break;
639
640 case ICMP_TIMXCEED_REASS:
641 str = "ip reassembly time exceeded";
642 break;
643
644 default:
645 (void)snprintf(buf, sizeof(buf), "time exceeded-#%u",
646 icmp_code);
647 break;
648 }
649 break;
650
651 case ICMP_PARAMPROB:
652 if (icmp_code)
653 (void)snprintf(buf, sizeof(buf),
654 "parameter problem - code %u", icmp_code);
655 else {
656 (void)snprintf(buf, sizeof(buf),
657 "parameter problem - octet %u",
658 GET_U_1(dp->icmp_pptr));
659 }
660 break;
661
662 case ICMP_MASKREPLY:
663 (void)snprintf(buf, sizeof(buf), "address mask is 0x%08x",
664 GET_BE_U_4(dp->icmp_mask));
665 break;
666
667 case ICMP_TSTAMP:
668 (void)snprintf(buf, sizeof(buf),
669 "time stamp query id %u seq %u",
670 GET_BE_U_2(dp->icmp_id),
671 GET_BE_U_2(dp->icmp_seq));
672 break;
673
674 case ICMP_TSTAMPREPLY:
675 (void)snprintf(buf, sizeof(buf),
676 "time stamp reply id %u seq %u: org %s",
677 GET_BE_U_2(dp->icmp_id),
678 GET_BE_U_2(dp->icmp_seq),
679 icmp_tstamp_print(GET_BE_U_4(dp->icmp_otime)));
680
681 (void)snprintf(buf+strlen(buf),sizeof(buf)-strlen(buf),", recv %s",
682 icmp_tstamp_print(GET_BE_U_4(dp->icmp_rtime)));
683 (void)snprintf(buf+strlen(buf),sizeof(buf)-strlen(buf),", xmit %s",
684 icmp_tstamp_print(GET_BE_U_4(dp->icmp_ttime)));
685 break;
686
687 default:
688 str = tok2str(icmp2str, "type-#%u", icmp_type);
689 break;
690 }
691 ND_PRINT("ICMP %s, length %u", str, plen);
692 if (ndo->ndo_vflag && !fragmented) { /* don't attempt checksumming if this is a frag */
693 if (ND_TTEST_LEN(bp, plen)) {
694 uint16_t sum;
695
696 vec[0].ptr = (const uint8_t *)(const void *)dp;
697 vec[0].len = plen;
698 sum = in_cksum(vec, 1);
699 if (sum != 0) {
700 uint16_t icmp_sum = GET_BE_U_2(dp->icmp_cksum);
701 ND_PRINT(" (wrong icmp cksum %x (->%x)!)",
702 icmp_sum,
703 in_cksum_shouldbe(icmp_sum, sum));
704 }
705 }
706 }
707
708 /*
709 * print the remnants of the IP packet.
710 * save the snaplength as this may get overridden in the IP printer.
711 */
712 if (ndo->ndo_vflag >= 1 && ICMP_ERRTYPE(icmp_type)) {
713 const struct ip *ip;
714 const u_char *snapend_save;
715
716 bp += 8;
717 ND_PRINT("\n\t");
718 ip = (const struct ip *)bp;
719 snapend_save = ndo->ndo_snapend;
720 /*
721 * Update the snapend because extensions (MPLS, ...) may be
722 * present after the IP packet. In this case the current
723 * (outer) packet's snapend is not what ip_print() needs to
724 * decode an IP packet nested in the middle of an ICMP payload.
725 *
726 * This prevents that, in ip_print(), for the nested IP packet,
727 * the remaining length < remaining caplen.
728 */
729 ndo->ndo_snapend = ND_MIN(bp + GET_BE_U_2(ip->ip_len),
730 ndo->ndo_snapend);
731 ip_print(ndo, bp, GET_BE_U_2(ip->ip_len));
732 ndo->ndo_snapend = snapend_save;
733 }
734
735 /* ndo_protocol reassignment after ip_print() call */
736 ndo->ndo_protocol = "icmp";
737
738 /*
739 * Attempt to decode multi-part message extensions (rfc4884) only for some ICMP types.
740 */
741 if (ndo->ndo_vflag >= 1 && plen > ICMP_EXTD_MINLEN && ICMP_MULTIPART_EXT_TYPE(icmp_type)) {
742 ND_TCHECK_SIZE(ext_dp);
743
744 /*
745 * Check first if the multi-part extension header shows a non-zero length.
746 * If the length field is not set then silently verify the checksum
747 * to check if an extension header is present. This is expedient,
748 * however not all implementations set the length field proper.
749 */
750 if (GET_U_1(ext_dp->icmp_length) == 0 &&
751 ND_TTEST_LEN(ext_dp->icmp_ext_version_res, plen - ICMP_EXTD_MINLEN)) {
752 vec[0].ptr = (const uint8_t *)(const void *)&ext_dp->icmp_ext_version_res;
753 vec[0].len = plen - ICMP_EXTD_MINLEN;
754 if (in_cksum(vec, 1)) {
755 return;
756 }
757 }
758
759 ND_PRINT("\n\tICMP Multi-Part extension v%u",
760 ICMP_EXT_EXTRACT_VERSION(*(ext_dp->icmp_ext_version_res)));
761
762 /*
763 * Sanity checking of the header.
764 */
765 if (ICMP_EXT_EXTRACT_VERSION(*(ext_dp->icmp_ext_version_res)) !=
766 ICMP_EXT_VERSION) {
767 ND_PRINT(" packet not supported");
768 return;
769 }
770
771 hlen = plen - ICMP_EXTD_MINLEN;
772 if (ND_TTEST_LEN(ext_dp->icmp_ext_version_res, hlen)) {
773 vec[0].ptr = (const uint8_t *)(const void *)&ext_dp->icmp_ext_version_res;
774 vec[0].len = hlen;
775 ND_PRINT(", checksum 0x%04x (%scorrect), length %u",
776 GET_BE_U_2(ext_dp->icmp_ext_checksum),
777 in_cksum(vec, 1) ? "in" : "",
778 hlen);
779 }
780
781 hlen -= 4; /* subtract common header size */
782 obj_tptr = (const uint8_t *)ext_dp->icmp_ext_data;
783
784 while (hlen > sizeof(struct icmp_multipart_ext_object_header_t)) {
785 u_int obj_tlen, obj_class_num, obj_ctype;
786 const struct icmp_multipart_ext_object_header_t *icmp_multipart_ext_object_header;
787
788 icmp_multipart_ext_object_header = (const struct icmp_multipart_ext_object_header_t *)obj_tptr;
789 obj_tlen = GET_BE_U_2(icmp_multipart_ext_object_header->length);
790 obj_class_num = GET_U_1(icmp_multipart_ext_object_header->class_num);
791 obj_ctype = GET_U_1(icmp_multipart_ext_object_header->ctype);
792 obj_tptr += sizeof(struct icmp_multipart_ext_object_header_t);
793
794 ND_PRINT("\n\t %s (%u), Class-Type: %u, length %u",
795 tok2str(icmp_multipart_ext_obj_values,"unknown",obj_class_num),
796 obj_class_num,
797 obj_ctype,
798 obj_tlen);
799
800 hlen-=sizeof(struct icmp_multipart_ext_object_header_t); /* length field includes tlv header */
801
802 /* infinite loop protection */
803 if ((obj_class_num == 0) ||
804 (obj_tlen < sizeof(struct icmp_multipart_ext_object_header_t))) {
805 return;
806 }
807 obj_tlen-=sizeof(struct icmp_multipart_ext_object_header_t);
808
809 switch (obj_class_num) {
810 case MPLS_STACK_ENTRY_OBJECT_CLASS:
811 switch(obj_ctype) {
812 case 1:
813 {
814 uint32_t raw_label;
815
816 raw_label = GET_BE_U_4(obj_tptr);
817 ND_PRINT("\n\t label %u, tc %u", MPLS_LABEL(raw_label), MPLS_TC(raw_label));
818 if (MPLS_STACK(raw_label))
819 ND_PRINT(", [S]");
820 ND_PRINT(", ttl %u", MPLS_TTL(raw_label));
821 break;
822 }
823 default:
824 print_unknown_data(ndo, obj_tptr, "\n\t ", obj_tlen);
825 }
826 break;
827
828 case INTERFACE_INFORMATION_OBJECT_CLASS:
829 {
830 /*
831 Ctype in a INTERFACE_INFORMATION_OBJECT_CLASS object:
832
833 Bit 0 1 2 3 4 5 6 7
834 +-------+-------+-------+-------+-------+-------+-------+-------+
835 | Interface Role| Rsvd1 | Rsvd2 |ifIndex| IPAddr| name | MTU |
836 +-------+-------+-------+-------+-------+-------+-------+-------+
837 */
838 const uint8_t *offset;
839 u_int interface_role, if_index_flag, ipaddr_flag, name_flag, mtu_flag;
840
841 interface_role = (obj_ctype & 0xc0) >> 6;
842 if_index_flag = (obj_ctype & 0x8) >> 3;
843 ipaddr_flag = (obj_ctype & 0x4) >> 2;
844 name_flag = (obj_ctype & 0x2) >> 1;
845 mtu_flag = (obj_ctype & 0x1);
846
847 ND_PRINT("\n\t Interface Role: %s",
848 tok2str(icmp_interface_information_role_values,
849 "an unknown interface role",interface_role));
850
851 offset = obj_tptr;
852
853 if (if_index_flag) {
854 ND_PRINT("\n\t Interface Index: %u", GET_BE_U_4(offset));
855 offset += 4;
856 }
857 if (ipaddr_flag) {
858 const struct icmp_interface_information_ipaddr_subobject_t *ipaddr_subobj;
859
860 ND_PRINT("\n\t IP Address sub-object: ");
861 ipaddr_subobj = (const struct icmp_interface_information_ipaddr_subobject_t *) offset;
862 switch (GET_BE_U_2(ipaddr_subobj->afi)) {
863 case 1:
864 ND_PRINT("%s", GET_IPADDR_STRING(ipaddr_subobj->ip_addr));
865 offset += 4;
866 break;
867 case 2:
868 ND_PRINT("%s", GET_IP6ADDR_STRING(ipaddr_subobj->ip_addr));
869 offset += 16;
870 break;
871 default:
872 ND_PRINT("Unknown Address Family Identifier");
873 return;
874 }
875 offset += 4;
876 }
877 if (name_flag) {
878 uint8_t inft_name_length_field;
879 const struct icmp_interface_information_ifname_subobject_t *ifname_subobj;
880
881 ifname_subobj = (const struct icmp_interface_information_ifname_subobject_t *) offset;
882 inft_name_length_field = GET_U_1(ifname_subobj->length);
883 ND_PRINT("\n\t Interface Name");
884 if (inft_name_length_field == 0) {
885 ND_PRINT(" [length %u]", inft_name_length_field);
886 nd_print_invalid(ndo);
887 break;
888 }
889 if (inft_name_length_field % 4 != 0) {
890 ND_PRINT(" [length %u != N x 4]", inft_name_length_field);
891 nd_print_invalid(ndo);
892 offset += inft_name_length_field;
893 break;
894 }
895 if (inft_name_length_field > 64) {
896 ND_PRINT(" [length %u > 64]", inft_name_length_field);
897 nd_print_invalid(ndo);
898 offset += inft_name_length_field;
899 break;
900 }
901 ND_PRINT(", length %u: ", inft_name_length_field);
902 nd_printjnp(ndo, ifname_subobj->if_name,
903 inft_name_length_field - 1);
904 offset += inft_name_length_field;
905 }
906 if (mtu_flag) {
907 ND_PRINT("\n\t MTU: %u", GET_BE_U_4(offset));
908 offset += 4;
909 }
910 break;
911 }
912
913 default:
914 print_unknown_data(ndo, obj_tptr, "\n\t ", obj_tlen);
915 break;
916 }
917 if (hlen < obj_tlen)
918 break;
919 hlen -= obj_tlen;
920 obj_tptr += obj_tlen;
921 }
922 }
923 }
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