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Fix incompatible pointer types with time functions calls on Windows
[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 #include <config.h>
25
26 #include "netdissect-stdinc.h"
27
28 #include <stdio.h>
29 #include <string.h>
30
31 #define ND_LONGJMP_FROM_TCHECK
32 #include "netdissect.h"
33 #include "addrtoname.h"
34 #include "extract.h"
35
36 #include "ip.h"
37 #include "udp.h"
38 #include "ipproto.h"
39 #include "mpls.h"
40
41 /*
42 * Interface Control Message Protocol Definitions.
43 * Per RFC 792, September 1981.
44 */
45
46 /*
47 * Structure of an icmp header.
48 */
49 struct icmp {
50 nd_uint8_t icmp_type; /* type of message, see below */
51 nd_uint8_t icmp_code; /* type sub code */
52 nd_uint16_t icmp_cksum; /* ones complement cksum of struct */
53 union {
54 nd_uint8_t ih_pptr; /* ICMP_PARAMPROB */
55 nd_ipv4 ih_gwaddr; /* ICMP_REDIRECT */
56 struct ih_idseq {
57 nd_uint16_t icd_id;
58 nd_uint16_t icd_seq;
59 } ih_idseq;
60 nd_uint32_t ih_void;
61 } icmp_hun;
62 #define icmp_pptr icmp_hun.ih_pptr
63 #define icmp_gwaddr icmp_hun.ih_gwaddr
64 #define icmp_id icmp_hun.ih_idseq.icd_id
65 #define icmp_seq icmp_hun.ih_idseq.icd_seq
66 #define icmp_void icmp_hun.ih_void
67 union {
68 struct id_ts {
69 nd_uint32_t its_otime;
70 nd_uint32_t its_rtime;
71 nd_uint32_t its_ttime;
72 } id_ts;
73 struct id_ip {
74 struct ip idi_ip;
75 /* options and then 64 bits of data */
76 } id_ip;
77 nd_uint32_t id_mask;
78 nd_byte id_data[1];
79 } icmp_dun;
80 #define icmp_otime icmp_dun.id_ts.its_otime
81 #define icmp_rtime icmp_dun.id_ts.its_rtime
82 #define icmp_ttime icmp_dun.id_ts.its_ttime
83 #define icmp_ip icmp_dun.id_ip.idi_ip
84 #define icmp_mask icmp_dun.id_mask
85 #define icmp_data icmp_dun.id_data
86 };
87
88 /*
89 * Lower bounds on packet lengths for various types.
90 * For the error advice packets must first insure that the
91 * packet is large enough to contain the returned ip header.
92 * Only then can we do the check to see if 64 bits of packet
93 * data have been returned, since we need to check the returned
94 * ip header length.
95 */
96 #define ICMP_MINLEN 8 /* abs minimum */
97 #define ICMP_EXTD_MINLEN (156 - sizeof (struct ip)) /* draft-bonica-internet-icmp-08 */
98 #define ICMP_TSLEN (8 + 3 * sizeof (uint32_t)) /* timestamp */
99 #define ICMP_MASKLEN 12 /* address mask */
100 #define ICMP_ADVLENMIN (8 + sizeof (struct ip) + 8) /* min */
101 #define ICMP_ADVLEN(p) (8 + (IP_HL(&(p)->icmp_ip) << 2) + 8)
102 /* N.B.: must separately check that ip_hl >= 5 */
103
104 /*
105 * Definition of type and code field values.
106 */
107 #define ICMP_ECHOREPLY 0 /* echo reply */
108 #define ICMP_UNREACH 3 /* dest unreachable, codes: */
109 #define ICMP_UNREACH_NET 0 /* bad net */
110 #define ICMP_UNREACH_HOST 1 /* bad host */
111 #define ICMP_UNREACH_PROTOCOL 2 /* bad protocol */
112 #define ICMP_UNREACH_PORT 3 /* bad port */
113 #define ICMP_UNREACH_NEEDFRAG 4 /* IP_DF caused drop */
114 #define ICMP_UNREACH_SRCFAIL 5 /* src route failed */
115 #define ICMP_UNREACH_NET_UNKNOWN 6 /* unknown net */
116 #define ICMP_UNREACH_HOST_UNKNOWN 7 /* unknown host */
117 #define ICMP_UNREACH_ISOLATED 8 /* src host isolated */
118 #define ICMP_UNREACH_NET_PROHIB 9 /* prohibited access */
119 #define ICMP_UNREACH_HOST_PROHIB 10 /* ditto */
120 #define ICMP_UNREACH_TOSNET 11 /* bad tos for net */
121 #define ICMP_UNREACH_TOSHOST 12 /* bad tos for host */
122 #define ICMP_SOURCEQUENCH 4 /* packet lost, slow down */
123 #define ICMP_REDIRECT 5 /* shorter route, codes: */
124 #define ICMP_REDIRECT_NET 0 /* for network */
125 #define ICMP_REDIRECT_HOST 1 /* for host */
126 #define ICMP_REDIRECT_TOSNET 2 /* for tos and net */
127 #define ICMP_REDIRECT_TOSHOST 3 /* for tos and host */
128 #define ICMP_ECHO 8 /* echo service */
129 #define ICMP_ROUTERADVERT 9 /* router advertisement */
130 #define ICMP_ROUTERSOLICIT 10 /* router solicitation */
131 #define ICMP_TIMXCEED 11 /* time exceeded, code: */
132 #define ICMP_TIMXCEED_INTRANS 0 /* ttl==0 in transit */
133 #define ICMP_TIMXCEED_REASS 1 /* ttl==0 in reass */
134 #define ICMP_PARAMPROB 12 /* ip header bad */
135 #define ICMP_PARAMPROB_OPTABSENT 1 /* req. opt. absent */
136 #define ICMP_TSTAMP 13 /* timestamp request */
137 #define ICMP_TSTAMPREPLY 14 /* timestamp reply */
138 #define ICMP_IREQ 15 /* information request */
139 #define ICMP_IREQREPLY 16 /* information reply */
140 #define ICMP_MASKREQ 17 /* address mask request */
141 #define ICMP_MASKREPLY 18 /* address mask reply */
142
143 #define ICMP_MAXTYPE 18
144
145 #define ICMP_ERRTYPE(type) \
146 ((type) == ICMP_UNREACH || (type) == ICMP_SOURCEQUENCH || \
147 (type) == ICMP_REDIRECT || (type) == ICMP_TIMXCEED || \
148 (type) == ICMP_PARAMPROB)
149 #define ICMP_MULTIPART_EXT_TYPE(type) \
150 ((type) == ICMP_UNREACH || \
151 (type) == ICMP_TIMXCEED || \
152 (type) == ICMP_PARAMPROB)
153 /* rfc1700 */
154 #ifndef ICMP_UNREACH_NET_UNKNOWN
155 #define ICMP_UNREACH_NET_UNKNOWN 6 /* destination net unknown */
156 #endif
157 #ifndef ICMP_UNREACH_HOST_UNKNOWN
158 #define ICMP_UNREACH_HOST_UNKNOWN 7 /* destination host unknown */
159 #endif
160 #ifndef ICMP_UNREACH_ISOLATED
161 #define ICMP_UNREACH_ISOLATED 8 /* source host isolated */
162 #endif
163 #ifndef ICMP_UNREACH_NET_PROHIB
164 #define ICMP_UNREACH_NET_PROHIB 9 /* admin prohibited net */
165 #endif
166 #ifndef ICMP_UNREACH_HOST_PROHIB
167 #define ICMP_UNREACH_HOST_PROHIB 10 /* admin prohibited host */
168 #endif
169 #ifndef ICMP_UNREACH_TOSNET
170 #define ICMP_UNREACH_TOSNET 11 /* tos prohibited net */
171 #endif
172 #ifndef ICMP_UNREACH_TOSHOST
173 #define ICMP_UNREACH_TOSHOST 12 /* tos prohibited host */
174 #endif
175
176 /* rfc1716 */
177 #ifndef ICMP_UNREACH_FILTER_PROHIB
178 #define ICMP_UNREACH_FILTER_PROHIB 13 /* admin prohibited filter */
179 #endif
180 #ifndef ICMP_UNREACH_HOST_PRECEDENCE
181 #define ICMP_UNREACH_HOST_PRECEDENCE 14 /* host precedence violation */
182 #endif
183 #ifndef ICMP_UNREACH_PRECEDENCE_CUTOFF
184 #define ICMP_UNREACH_PRECEDENCE_CUTOFF 15 /* precedence cutoff */
185 #endif
186
187 /* Most of the icmp types */
188 static const struct tok icmp2str[] = {
189 { ICMP_ECHOREPLY, "echo reply" },
190 { ICMP_SOURCEQUENCH, "source quench" },
191 { ICMP_ECHO, "echo request" },
192 { ICMP_ROUTERSOLICIT, "router solicitation" },
193 { ICMP_TSTAMP, "time stamp request" },
194 { ICMP_TSTAMPREPLY, "time stamp reply" },
195 { ICMP_IREQ, "information request" },
196 { ICMP_IREQREPLY, "information reply" },
197 { ICMP_MASKREQ, "address mask request" },
198 { 0, NULL }
199 };
200
201 /* rfc1191 */
202 struct mtu_discovery {
203 nd_uint16_t unused;
204 nd_uint16_t nexthopmtu;
205 };
206
207 /* rfc1256 */
208 struct ih_rdiscovery {
209 nd_uint8_t ird_addrnum;
210 nd_uint8_t ird_addrsiz;
211 nd_uint16_t ird_lifetime;
212 };
213
214 struct id_rdiscovery {
215 nd_uint32_t ird_addr;
216 nd_uint32_t ird_pref;
217 };
218
219 /*
220 * RFC 4884 - Extended ICMP to Support Multi-Part Messages
221 *
222 * This is a general extension mechanism, based on the mechanism
223 * in draft-bonica-icmp-mpls-02 ICMP Extensions for MultiProtocol
224 * Label Switching.
225 *
226 * The Destination Unreachable, Time Exceeded
227 * and Parameter Problem messages are slightly changed as per
228 * the above RFC. A new Length field gets added to give
229 * the caller an idea about the length of the piggybacked
230 * IP packet before the 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 /*
263 * Extract version from the first octet of icmp_ext_version_res.
264 */
265 #define ICMP_EXT_EXTRACT_VERSION(x) (((x)&0xf0)>>4)
266
267 /*
268 * Current version.
269 */
270 #define ICMP_EXT_VERSION 2
271
272 /*
273 * Extension object class numbers.
274 *
275 * Class 1 dates back to draft-bonica-icmp-mpls-02.
276 *
277 * Class 2 was used for an "Extended Payload Object Class", which
278 * contained bytes of the payload beyond the first 128 bytes, in
279 * draft-bonica-icmp-mpls-02; it was reassigned to an "Interface
280 * Information Object" in RFC 5837.
281 */
282
283 /* rfc4950 */
284 #define MPLS_STACK_ENTRY_OBJECT_CLASS 1
285 /* rfc5837 */
286 #define INTERFACE_INFORMATION_OBJECT_CLASS 2
287
288 struct icmp_multipart_ext_object_header_t {
289 nd_uint16_t length;
290 nd_uint8_t class_num;
291 nd_uint8_t ctype;
292 };
293
294 static const struct tok icmp_multipart_ext_obj_values[] = {
295 { 1, "MPLS Stack Entry Object" },
296 { 2, "Interface Information Object" },
297 { 0, NULL}
298 };
299
300 /* rfc5837 */
301 static const struct tok icmp_interface_information_role_values[] = {
302 { 0, "Incoming IP Interface"},
303 { 1, "Sub-IP Component of Incoming IP Interface"},
304 { 2, "Outgoing IP Interface"},
305 { 3, "IP Next hop"},
306 { 0, NULL }
307 };
308
309 /*
310 Interface IP Address Sub-Object
311 0 31
312 +-------+-------+-------+-------+
313 | AFI | Reserved |
314 +-------+-------+-------+-------+
315 | IP Address ....
316 */
317 struct icmp_interface_information_ipaddr_subobject_t {
318 nd_uint16_t afi;
319 nd_uint16_t reserved;
320 nd_uint32_t ip_addr;
321 };
322
323 /*
324 Interface Name Sub-Object
325 octet 0 1 63
326 +--------+-----------................-----------------+
327 | length | interface name octets 1-63 |
328 +--------+-----------................-----------------+
329 */
330 struct icmp_interface_information_ifname_subobject_t {
331 nd_uint8_t length;
332 nd_byte if_name[63];
333 };
334
335 /* prototypes */
336 const char *icmp_tstamp_print(u_int);
337
338 /* print the milliseconds since midnight UTC */
339 const char *
340 icmp_tstamp_print(u_int tstamp)
341 {
342 u_int msec,sec,min,hrs;
343
344 static char buf[64];
345
346 msec = tstamp % 1000;
347 sec = tstamp / 1000;
348 min = sec / 60; sec -= min * 60;
349 hrs = min / 60; min -= hrs * 60;
350 snprintf(buf, sizeof(buf), "%02u:%02u:%02u.%03u",hrs,min,sec,msec);
351 return buf;
352 }
353
354 static int
355 print_icmp_multipart_ext_object(netdissect_options *ndo, const uint8_t *obj_tptr)
356 {
357 u_int obj_tlen, obj_class_num, obj_ctype;
358 const struct icmp_multipart_ext_object_header_t *icmp_multipart_ext_object_header;
359
360 icmp_multipart_ext_object_header = (const struct icmp_multipart_ext_object_header_t *)obj_tptr;
361 obj_tlen = GET_BE_U_2(icmp_multipart_ext_object_header->length);
362 obj_class_num = GET_U_1(icmp_multipart_ext_object_header->class_num);
363 obj_ctype = GET_U_1(icmp_multipart_ext_object_header->ctype);
364 obj_tptr += sizeof(struct icmp_multipart_ext_object_header_t);
365
366 ND_PRINT("\n\t %s (%u), Class-Type: %u, length %u",
367 tok2str(icmp_multipart_ext_obj_values,"unknown",obj_class_num),
368 obj_class_num,
369 obj_ctype,
370 obj_tlen);
371
372 /* infinite loop protection */
373 if ((obj_class_num == 0) ||
374 (obj_tlen < sizeof(struct icmp_multipart_ext_object_header_t))) {
375 return -1;
376 }
377 obj_tlen -= sizeof(struct icmp_multipart_ext_object_header_t);
378
379 switch (obj_class_num) {
380 case MPLS_STACK_ENTRY_OBJECT_CLASS:
381 switch(obj_ctype) {
382 case 1:
383 {
384 uint32_t raw_label;
385
386 raw_label = GET_BE_U_4(obj_tptr);
387 ND_PRINT("\n\t label %u, tc %u", MPLS_LABEL(raw_label), MPLS_TC(raw_label));
388 if (MPLS_STACK(raw_label))
389 ND_PRINT(", [S]");
390 ND_PRINT(", ttl %u", MPLS_TTL(raw_label));
391 break;
392 }
393 default:
394 print_unknown_data(ndo, obj_tptr, "\n\t ", obj_tlen);
395 }
396 break;
397
398 case INTERFACE_INFORMATION_OBJECT_CLASS:
399 {
400 /*
401 Ctype in a INTERFACE_INFORMATION_OBJECT_CLASS object:
402
403 Bit 0 1 2 3 4 5 6 7
404 +-------+-------+-------+-------+-------+-------+-------+-------+
405 | Interface Role| Rsvd1 | Rsvd2 |ifIndex| IPAddr| name | MTU |
406 +-------+-------+-------+-------+-------+-------+-------+-------+
407 */
408 const uint8_t *offset;
409 u_int interface_role, if_index_flag, ipaddr_flag, name_flag, mtu_flag;
410
411 interface_role = (obj_ctype & 0xc0) >> 6;
412 if_index_flag = (obj_ctype & 0x8) >> 3;
413 ipaddr_flag = (obj_ctype & 0x4) >> 2;
414 name_flag = (obj_ctype & 0x2) >> 1;
415 mtu_flag = (obj_ctype & 0x1);
416
417 ND_PRINT("\n\t Interface Role: %s",
418 tok2str(icmp_interface_information_role_values,
419 "an unknown interface role",interface_role));
420
421 offset = obj_tptr;
422
423 if (if_index_flag) {
424 ND_PRINT("\n\t Interface Index: %u", GET_BE_U_4(offset));
425 offset += 4;
426 }
427 if (ipaddr_flag) {
428 const struct icmp_interface_information_ipaddr_subobject_t *ipaddr_subobj;
429
430 ND_PRINT("\n\t IP Address sub-object: ");
431 ipaddr_subobj = (const struct icmp_interface_information_ipaddr_subobject_t *) offset;
432 switch (GET_BE_U_2(ipaddr_subobj->afi)) {
433 case 1:
434 ND_PRINT("%s", GET_IPADDR_STRING(ipaddr_subobj->ip_addr));
435 offset += 4;
436 break;
437 case 2:
438 ND_PRINT("%s", GET_IP6ADDR_STRING(ipaddr_subobj->ip_addr));
439 offset += 16;
440 break;
441 default:
442 ND_PRINT("Unknown Address Family Identifier");
443 return -1;
444 }
445 offset += 4;
446 }
447 if (name_flag) {
448 uint8_t inft_name_length_field;
449 const struct icmp_interface_information_ifname_subobject_t *ifname_subobj;
450
451 ifname_subobj = (const struct icmp_interface_information_ifname_subobject_t *) offset;
452 inft_name_length_field = GET_U_1(ifname_subobj->length);
453 ND_PRINT("\n\t Interface Name");
454 if (inft_name_length_field == 0) {
455 ND_PRINT(" [length %u]", inft_name_length_field);
456 nd_print_invalid(ndo);
457 break;
458 }
459 if (inft_name_length_field % 4 != 0) {
460 ND_PRINT(" [length %u != N x 4]", inft_name_length_field);
461 nd_print_invalid(ndo);
462 offset += inft_name_length_field;
463 break;
464 }
465 if (inft_name_length_field > 64) {
466 ND_PRINT(" [length %u > 64]", inft_name_length_field);
467 nd_print_invalid(ndo);
468 offset += inft_name_length_field;
469 break;
470 }
471 ND_PRINT(", length %u: ", inft_name_length_field);
472 nd_printjnp(ndo, ifname_subobj->if_name,
473 inft_name_length_field - 1);
474 offset += inft_name_length_field;
475 }
476 if (mtu_flag) {
477 ND_PRINT("\n\t MTU: %u", GET_BE_U_4(offset));
478 offset += 4;
479 }
480 break;
481 }
482
483 default:
484 print_unknown_data(ndo, obj_tptr, "\n\t ", obj_tlen);
485 break;
486 }
487 return obj_tlen + sizeof(struct icmp_multipart_ext_object_header_t);
488 }
489
490 void
491 icmp_print(netdissect_options *ndo, const u_char *bp, u_int plen,
492 int fragmented)
493 {
494 const struct icmp *dp;
495 uint8_t icmp_type, icmp_code;
496 const struct icmp_ext_t *ext_dp;
497 const char *str;
498 const uint8_t *obj_tptr;
499 u_int hlen;
500 char buf[512];
501 struct cksum_vec vec[1];
502
503 ndo->ndo_protocol = "icmp";
504 dp = (const struct icmp *)bp;
505 ext_dp = (const struct icmp_ext_t *)bp;
506 str = buf;
507
508 icmp_type = GET_U_1(dp->icmp_type);
509 icmp_code = GET_U_1(dp->icmp_code);
510 switch (icmp_type) {
511
512 case ICMP_ECHO:
513 case ICMP_ECHOREPLY:
514 (void)snprintf(buf, sizeof(buf), "echo %s, id %u, seq %u",
515 icmp_type == ICMP_ECHO ?
516 "request" : "reply",
517 GET_BE_U_2(dp->icmp_id),
518 GET_BE_U_2(dp->icmp_seq));
519 break;
520
521 case ICMP_UNREACH:
522 switch (icmp_code) {
523
524 case ICMP_UNREACH_NET:
525 (void)snprintf(buf, sizeof(buf),
526 "net %s unreachable",
527 GET_IPADDR_STRING(dp->icmp_ip.ip_dst));
528 break;
529
530 case ICMP_UNREACH_HOST:
531 (void)snprintf(buf, sizeof(buf),
532 "host %s unreachable",
533 GET_IPADDR_STRING(dp->icmp_ip.ip_dst));
534 break;
535
536 case ICMP_UNREACH_PROTOCOL:
537 (void)snprintf(buf, sizeof(buf),
538 "%s protocol %u unreachable",
539 GET_IPADDR_STRING(dp->icmp_ip.ip_dst),
540 GET_U_1(dp->icmp_ip.ip_p));
541 break;
542
543 case ICMP_UNREACH_PORT:
544 {
545 const struct ip *oip;
546 const struct udphdr *ouh;
547 uint8_t ip_proto;
548 uint16_t dport;
549
550 oip = &dp->icmp_ip;
551 hlen = IP_HL(oip) * 4;
552 ouh = (const struct udphdr *)(((const u_char *)oip) + hlen);
553 dport = GET_BE_U_2(ouh->uh_dport);
554 ip_proto = GET_U_1(oip->ip_p);
555 switch (ip_proto) {
556
557 case IPPROTO_TCP:
558 (void)snprintf(buf, sizeof(buf),
559 "%s tcp port %s unreachable",
560 GET_IPADDR_STRING(oip->ip_dst),
561 tcpport_string(ndo, dport));
562 break;
563
564 case IPPROTO_UDP:
565 (void)snprintf(buf, sizeof(buf),
566 "%s udp port %s unreachable",
567 GET_IPADDR_STRING(oip->ip_dst),
568 udpport_string(ndo, dport));
569 break;
570
571 default:
572 (void)snprintf(buf, sizeof(buf),
573 "%s protocol %u port %u unreachable",
574 GET_IPADDR_STRING(oip->ip_dst),
575 ip_proto, dport);
576 break;
577 }
578 break;
579 }
580
581 case ICMP_UNREACH_NEEDFRAG:
582 {
583 const struct mtu_discovery *mp;
584 u_int mtu;
585
586 mp = (const struct mtu_discovery *)(const u_char *)&dp->icmp_void;
587 mtu = GET_BE_U_2(mp->nexthopmtu);
588 if (mtu) {
589 (void)snprintf(buf, sizeof(buf),
590 "%s unreachable - need to frag (mtu %u)",
591 GET_IPADDR_STRING(dp->icmp_ip.ip_dst), mtu);
592 } else {
593 (void)snprintf(buf, sizeof(buf),
594 "%s unreachable - need to frag",
595 GET_IPADDR_STRING(dp->icmp_ip.ip_dst));
596 }
597 }
598 break;
599
600 case ICMP_UNREACH_SRCFAIL:
601 (void)snprintf(buf, sizeof(buf),
602 "%s unreachable - source route failed",
603 GET_IPADDR_STRING(dp->icmp_ip.ip_dst));
604 break;
605
606 case ICMP_UNREACH_NET_UNKNOWN:
607 (void)snprintf(buf, sizeof(buf),
608 "net %s unreachable - unknown",
609 GET_IPADDR_STRING(dp->icmp_ip.ip_dst));
610 break;
611
612 case ICMP_UNREACH_HOST_UNKNOWN:
613 (void)snprintf(buf, sizeof(buf),
614 "host %s unreachable - unknown",
615 GET_IPADDR_STRING(dp->icmp_ip.ip_dst));
616 break;
617
618 case ICMP_UNREACH_ISOLATED:
619 (void)snprintf(buf, sizeof(buf),
620 "%s unreachable - source host isolated",
621 GET_IPADDR_STRING(dp->icmp_ip.ip_dst));
622 break;
623
624 case ICMP_UNREACH_NET_PROHIB:
625 (void)snprintf(buf, sizeof(buf),
626 "net %s unreachable - admin prohibited",
627 GET_IPADDR_STRING(dp->icmp_ip.ip_dst));
628 break;
629
630 case ICMP_UNREACH_HOST_PROHIB:
631 (void)snprintf(buf, sizeof(buf),
632 "host %s unreachable - admin prohibited",
633 GET_IPADDR_STRING(dp->icmp_ip.ip_dst));
634 break;
635
636 case ICMP_UNREACH_TOSNET:
637 (void)snprintf(buf, sizeof(buf),
638 "net %s unreachable - tos prohibited",
639 GET_IPADDR_STRING(dp->icmp_ip.ip_dst));
640 break;
641
642 case ICMP_UNREACH_TOSHOST:
643 (void)snprintf(buf, sizeof(buf),
644 "host %s unreachable - tos prohibited",
645 GET_IPADDR_STRING(dp->icmp_ip.ip_dst));
646 break;
647
648 case ICMP_UNREACH_FILTER_PROHIB:
649 (void)snprintf(buf, sizeof(buf),
650 "host %s unreachable - admin prohibited filter",
651 GET_IPADDR_STRING(dp->icmp_ip.ip_dst));
652 break;
653
654 case ICMP_UNREACH_HOST_PRECEDENCE:
655 (void)snprintf(buf, sizeof(buf),
656 "host %s unreachable - host precedence violation",
657 GET_IPADDR_STRING(dp->icmp_ip.ip_dst));
658 break;
659
660 case ICMP_UNREACH_PRECEDENCE_CUTOFF:
661 (void)snprintf(buf, sizeof(buf),
662 "host %s unreachable - precedence cutoff",
663 GET_IPADDR_STRING(dp->icmp_ip.ip_dst));
664 break;
665
666 default:
667 (void)snprintf(buf, sizeof(buf),
668 "%s unreachable - #%u",
669 GET_IPADDR_STRING(dp->icmp_ip.ip_dst),
670 icmp_code);
671 break;
672 }
673 break;
674
675 case ICMP_REDIRECT:
676 switch (icmp_code) {
677
678 case ICMP_REDIRECT_NET:
679 (void)snprintf(buf, sizeof(buf),
680 "redirect %s to net %s",
681 GET_IPADDR_STRING(dp->icmp_ip.ip_dst),
682 GET_IPADDR_STRING(dp->icmp_gwaddr));
683 break;
684
685 case ICMP_REDIRECT_HOST:
686 (void)snprintf(buf, sizeof(buf),
687 "redirect %s to host %s",
688 GET_IPADDR_STRING(dp->icmp_ip.ip_dst),
689 GET_IPADDR_STRING(dp->icmp_gwaddr));
690 break;
691
692 case ICMP_REDIRECT_TOSNET:
693 (void)snprintf(buf, sizeof(buf),
694 "redirect-tos %s to net %s",
695 GET_IPADDR_STRING(dp->icmp_ip.ip_dst),
696 GET_IPADDR_STRING(dp->icmp_gwaddr));
697 break;
698
699 case ICMP_REDIRECT_TOSHOST:
700 (void)snprintf(buf, sizeof(buf),
701 "redirect-tos %s to host %s",
702 GET_IPADDR_STRING(dp->icmp_ip.ip_dst),
703 GET_IPADDR_STRING(dp->icmp_gwaddr));
704 break;
705
706 default:
707 (void)snprintf(buf, sizeof(buf),
708 "redirect-#%u %s to %s", icmp_code,
709 GET_IPADDR_STRING(dp->icmp_ip.ip_dst),
710 GET_IPADDR_STRING(dp->icmp_gwaddr));
711 break;
712 }
713 break;
714
715 case ICMP_ROUTERADVERT:
716 {
717 char *cp;
718 const struct ih_rdiscovery *ihp;
719 const struct id_rdiscovery *idp;
720 u_int lifetime, num, size;
721
722 (void)snprintf(buf, sizeof(buf), "router advertisement");
723 cp = buf + strlen(buf);
724
725 ihp = (const struct ih_rdiscovery *)&dp->icmp_void;
726 (void)strncpy(cp, " lifetime ", sizeof(buf) - (cp - buf));
727 cp = buf + strlen(buf);
728 lifetime = GET_BE_U_2(ihp->ird_lifetime);
729 if (lifetime < 60) {
730 (void)snprintf(cp, sizeof(buf) - (cp - buf), "%u",
731 lifetime);
732 } else if (lifetime < 60 * 60) {
733 (void)snprintf(cp, sizeof(buf) - (cp - buf), "%u:%02u",
734 lifetime / 60, lifetime % 60);
735 } else {
736 (void)snprintf(cp, sizeof(buf) - (cp - buf),
737 "%u:%02u:%02u",
738 lifetime / 3600,
739 (lifetime % 3600) / 60,
740 lifetime % 60);
741 }
742 cp = buf + strlen(buf);
743
744 num = GET_U_1(ihp->ird_addrnum);
745 (void)snprintf(cp, sizeof(buf) - (cp - buf), " %u:", num);
746 cp = buf + strlen(buf);
747
748 size = GET_U_1(ihp->ird_addrsiz);
749 if (size != 2) {
750 (void)snprintf(cp, sizeof(buf) - (cp - buf),
751 " [size %u]", size);
752 break;
753 }
754 idp = (const struct id_rdiscovery *)&dp->icmp_data;
755 while (num != 0) {
756 (void)snprintf(cp, sizeof(buf) - (cp - buf), " {%s %u}",
757 GET_IPADDR_STRING(idp->ird_addr),
758 GET_BE_U_4(idp->ird_pref));
759 cp = buf + strlen(buf);
760 ++idp;
761 num--;
762 }
763 }
764 break;
765
766 case ICMP_TIMXCEED:
767 ND_TCHECK_4(dp->icmp_ip.ip_dst);
768 switch (icmp_code) {
769
770 case ICMP_TIMXCEED_INTRANS:
771 str = "time exceeded in-transit";
772 break;
773
774 case ICMP_TIMXCEED_REASS:
775 str = "ip reassembly time exceeded";
776 break;
777
778 default:
779 (void)snprintf(buf, sizeof(buf), "time exceeded-#%u",
780 icmp_code);
781 break;
782 }
783 break;
784
785 case ICMP_PARAMPROB:
786 if (icmp_code)
787 (void)snprintf(buf, sizeof(buf),
788 "parameter problem - code %u", icmp_code);
789 else {
790 (void)snprintf(buf, sizeof(buf),
791 "parameter problem - octet %u",
792 GET_U_1(dp->icmp_pptr));
793 }
794 break;
795
796 case ICMP_MASKREPLY:
797 (void)snprintf(buf, sizeof(buf), "address mask is 0x%08x",
798 GET_BE_U_4(dp->icmp_mask));
799 break;
800
801 case ICMP_TSTAMP:
802 (void)snprintf(buf, sizeof(buf),
803 "time stamp query id %u seq %u",
804 GET_BE_U_2(dp->icmp_id),
805 GET_BE_U_2(dp->icmp_seq));
806 break;
807
808 case ICMP_TSTAMPREPLY:
809 (void)snprintf(buf, sizeof(buf),
810 "time stamp reply id %u seq %u: org %s",
811 GET_BE_U_2(dp->icmp_id),
812 GET_BE_U_2(dp->icmp_seq),
813 icmp_tstamp_print(GET_BE_U_4(dp->icmp_otime)));
814
815 (void)snprintf(buf+strlen(buf),sizeof(buf)-strlen(buf),", recv %s",
816 icmp_tstamp_print(GET_BE_U_4(dp->icmp_rtime)));
817 (void)snprintf(buf+strlen(buf),sizeof(buf)-strlen(buf),", xmit %s",
818 icmp_tstamp_print(GET_BE_U_4(dp->icmp_ttime)));
819 break;
820
821 default:
822 str = tok2str(icmp2str, "type-#%u", icmp_type);
823 break;
824 }
825 ND_PRINT("ICMP %s, length %u", str, plen);
826 if (ndo->ndo_vflag && !fragmented) { /* don't attempt checksumming if this is a frag */
827 if (ND_TTEST_LEN(bp, plen)) {
828 uint16_t sum;
829
830 vec[0].ptr = (const uint8_t *)(const void *)dp;
831 vec[0].len = plen;
832 sum = in_cksum(vec, 1);
833 if (sum != 0) {
834 uint16_t icmp_sum = GET_BE_U_2(dp->icmp_cksum);
835 ND_PRINT(" (wrong icmp cksum %x (->%x)!)",
836 icmp_sum,
837 in_cksum_shouldbe(icmp_sum, sum));
838 }
839 }
840 }
841
842 /*
843 * print the remnants of the IP packet.
844 * save the snaplength as this may get overridden in the IP printer.
845 */
846 if (ndo->ndo_vflag >= 1 && ICMP_ERRTYPE(icmp_type)) {
847 const struct ip *ip;
848 const u_char *snapend_save;
849
850 bp += 8;
851 ND_PRINT("\n\t");
852 ip = (const struct ip *)bp;
853 snapend_save = ndo->ndo_snapend;
854 /*
855 * Update the snapend because extensions (MPLS, ...) may be
856 * present after the IP packet. In this case the current
857 * (outer) packet's snapend is not what ip_print() needs to
858 * decode an IP packet nested in the middle of an ICMP payload.
859 *
860 * This prevents that, in ip_print(), for the nested IP packet,
861 * the remaining length < remaining caplen.
862 */
863 ndo->ndo_snapend = ND_MIN(bp + GET_BE_U_2(ip->ip_len),
864 ndo->ndo_snapend);
865 ip_print(ndo, bp, GET_BE_U_2(ip->ip_len));
866 ndo->ndo_snapend = snapend_save;
867 }
868
869 /* ndo_protocol reassignment after ip_print() call */
870 ndo->ndo_protocol = "icmp";
871
872 /*
873 * Attempt to decode multi-part message extensions (rfc4884) only for some ICMP types.
874 */
875 if (ndo->ndo_vflag >= 1 && plen > ICMP_EXTD_MINLEN && ICMP_MULTIPART_EXT_TYPE(icmp_type)) {
876 ND_TCHECK_SIZE(ext_dp);
877
878 /*
879 * Check first if the multi-part extension header shows a non-zero length.
880 * If the length field is not set then silently verify the checksum
881 * to check if an extension header is present. This is expedient,
882 * however not all implementations set the length field proper.
883 */
884 if (GET_U_1(ext_dp->icmp_length) == 0 &&
885 ND_TTEST_LEN(ext_dp->icmp_ext_version_res, plen - ICMP_EXTD_MINLEN)) {
886 vec[0].ptr = (const uint8_t *)(const void *)&ext_dp->icmp_ext_version_res;
887 vec[0].len = plen - ICMP_EXTD_MINLEN;
888 if (in_cksum(vec, 1)) {
889 return;
890 }
891 }
892
893 ND_PRINT("\n\tICMP Multi-Part extension v%u",
894 ICMP_EXT_EXTRACT_VERSION(*(ext_dp->icmp_ext_version_res)));
895
896 /*
897 * Sanity checking of the header.
898 */
899 if (ICMP_EXT_EXTRACT_VERSION(*(ext_dp->icmp_ext_version_res)) !=
900 ICMP_EXT_VERSION) {
901 ND_PRINT(" packet not supported");
902 return;
903 }
904
905 hlen = plen - ICMP_EXTD_MINLEN;
906 if (ND_TTEST_LEN(ext_dp->icmp_ext_version_res, hlen)) {
907 vec[0].ptr = (const uint8_t *)(const void *)&ext_dp->icmp_ext_version_res;
908 vec[0].len = hlen;
909 ND_PRINT(", checksum 0x%04x (%scorrect), length %u",
910 GET_BE_U_2(ext_dp->icmp_ext_checksum),
911 in_cksum(vec, 1) ? "in" : "",
912 hlen);
913 }
914
915 hlen -= 4; /* subtract common header size */
916 obj_tptr = (const uint8_t *)ext_dp->icmp_ext_data;
917
918 while (hlen > sizeof(struct icmp_multipart_ext_object_header_t)) {
919 int obj_tlen = print_icmp_multipart_ext_object(ndo, obj_tptr);
920 if (obj_tlen < 0) {
921 /* malformed object */
922 return;
923 }
924 if (hlen < (u_int)obj_tlen)
925 break;
926 hlen -= obj_tlen;
927 obj_tptr += obj_tlen;
928 }
929 }
930 }
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