2 * Copyright (c) 1988, 1989, 1990, 1991, 1993, 1994, 1995, 1996
3 * The Regents of the University of California. All rights reserved.
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
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.
25 static const char rcsid[] _U_ =
26 "@(#) $Header: /tcpdump/master/tcpdump/print-icmp.c,v 1.73.2.3 2004/03/24 00:56:34 guy Exp $ (LBL)";
33 #include <tcpdump-stdinc.h>
38 #include "interface.h"
39 #include "addrtoname.h"
40 #include "extract.h" /* must come after interface.h */
47 * Interface Control Message Protocol Definitions.
48 * Per RFC 792, September 1981.
52 * Structure of an icmp header.
55 u_int8_t icmp_type; /* type of message, see below */
56 u_int8_t icmp_code; /* type sub code */
57 u_int16_t icmp_cksum; /* ones complement cksum of struct */
59 u_int8_t ih_pptr; /* ICMP_PARAMPROB */
60 struct in_addr ih_gwaddr; /* ICMP_REDIRECT */
67 /* ICMP_UNREACH_NEEDFRAG -- Path MTU Discovery (RFC1191) */
70 u_int16_t ipm_nextmtu;
73 #define icmp_pptr icmp_hun.ih_pptr
74 #define icmp_gwaddr icmp_hun.ih_gwaddr
75 #define icmp_id icmp_hun.ih_idseq.icd_id
76 #define icmp_seq icmp_hun.ih_idseq.icd_seq
77 #define icmp_void icmp_hun.ih_void
78 #define icmp_pmvoid icmp_hun.ih_pmtu.ipm_void
79 #define icmp_nextmtu icmp_hun.ih_pmtu.ipm_nextmtu
88 /* options and then 64 bits of data */
93 #define icmp_otime icmp_dun.id_ts.its_otime
94 #define icmp_rtime icmp_dun.id_ts.its_rtime
95 #define icmp_ttime icmp_dun.id_ts.its_ttime
96 #define icmp_ip icmp_dun.id_ip.idi_ip
97 #define icmp_mask icmp_dun.id_mask
98 #define icmp_data icmp_dun.id_data
102 * Lower bounds on packet lengths for various types.
103 * For the error advice packets must first insure that the
104 * packet is large enought to contain the returned ip header.
105 * Only then can we do the check to see if 64 bits of packet
106 * data have been returned, since we need to check the returned
109 #define ICMP_MINLEN 8 /* abs minimum */
110 #define ICMP_TSLEN (8 + 3 * sizeof (u_int32_t)) /* timestamp */
111 #define ICMP_MASKLEN 12 /* address mask */
112 #define ICMP_ADVLENMIN (8 + sizeof (struct ip) + 8) /* min */
113 #define ICMP_ADVLEN(p) (8 + (IP_HL(&(p)->icmp_ip) << 2) + 8)
114 /* N.B.: must separately check that ip_hl >= 5 */
117 * Definition of type and code field values.
119 #define ICMP_ECHOREPLY 0 /* echo reply */
120 #define ICMP_UNREACH 3 /* dest unreachable, codes: */
121 #define ICMP_UNREACH_NET 0 /* bad net */
122 #define ICMP_UNREACH_HOST 1 /* bad host */
123 #define ICMP_UNREACH_PROTOCOL 2 /* bad protocol */
124 #define ICMP_UNREACH_PORT 3 /* bad port */
125 #define ICMP_UNREACH_NEEDFRAG 4 /* IP_DF caused drop */
126 #define ICMP_UNREACH_SRCFAIL 5 /* src route failed */
127 #define ICMP_UNREACH_NET_UNKNOWN 6 /* unknown net */
128 #define ICMP_UNREACH_HOST_UNKNOWN 7 /* unknown host */
129 #define ICMP_UNREACH_ISOLATED 8 /* src host isolated */
130 #define ICMP_UNREACH_NET_PROHIB 9 /* prohibited access */
131 #define ICMP_UNREACH_HOST_PROHIB 10 /* ditto */
132 #define ICMP_UNREACH_TOSNET 11 /* bad tos for net */
133 #define ICMP_UNREACH_TOSHOST 12 /* bad tos for host */
134 #define ICMP_SOURCEQUENCH 4 /* packet lost, slow down */
135 #define ICMP_REDIRECT 5 /* shorter route, codes: */
136 #define ICMP_REDIRECT_NET 0 /* for network */
137 #define ICMP_REDIRECT_HOST 1 /* for host */
138 #define ICMP_REDIRECT_TOSNET 2 /* for tos and net */
139 #define ICMP_REDIRECT_TOSHOST 3 /* for tos and host */
140 #define ICMP_ECHO 8 /* echo service */
141 #define ICMP_ROUTERADVERT 9 /* router advertisement */
142 #define ICMP_ROUTERSOLICIT 10 /* router solicitation */
143 #define ICMP_TIMXCEED 11 /* time exceeded, code: */
144 #define ICMP_TIMXCEED_INTRANS 0 /* ttl==0 in transit */
145 #define ICMP_TIMXCEED_REASS 1 /* ttl==0 in reass */
146 #define ICMP_PARAMPROB 12 /* ip header bad */
147 #define ICMP_PARAMPROB_OPTABSENT 1 /* req. opt. absent */
148 #define ICMP_TSTAMP 13 /* timestamp request */
149 #define ICMP_TSTAMPREPLY 14 /* timestamp reply */
150 #define ICMP_IREQ 15 /* information request */
151 #define ICMP_IREQREPLY 16 /* information reply */
152 #define ICMP_MASKREQ 17 /* address mask request */
153 #define ICMP_MASKREPLY 18 /* address mask reply */
155 #define ICMP_MAXTYPE 18
157 #define ICMP_INFOTYPE(type) \
158 ((type) == ICMP_ECHOREPLY || (type) == ICMP_ECHO || \
159 (type) == ICMP_ROUTERADVERT || (type) == ICMP_ROUTERSOLICIT || \
160 (type) == ICMP_TSTAMP || (type) == ICMP_TSTAMPREPLY || \
161 (type) == ICMP_IREQ || (type) == ICMP_IREQREPLY || \
162 (type) == ICMP_MASKREQ || (type) == ICMP_MASKREPLY)
164 #ifndef ICMP_UNREACH_NET_UNKNOWN
165 #define ICMP_UNREACH_NET_UNKNOWN 6 /* destination net unknown */
167 #ifndef ICMP_UNREACH_HOST_UNKNOWN
168 #define ICMP_UNREACH_HOST_UNKNOWN 7 /* destination host unknown */
170 #ifndef ICMP_UNREACH_ISOLATED
171 #define ICMP_UNREACH_ISOLATED 8 /* source host isolated */
173 #ifndef ICMP_UNREACH_NET_PROHIB
174 #define ICMP_UNREACH_NET_PROHIB 9 /* admin prohibited net */
176 #ifndef ICMP_UNREACH_HOST_PROHIB
177 #define ICMP_UNREACH_HOST_PROHIB 10 /* admin prohibited host */
179 #ifndef ICMP_UNREACH_TOSNET
180 #define ICMP_UNREACH_TOSNET 11 /* tos prohibited net */
182 #ifndef ICMP_UNREACH_TOSHOST
183 #define ICMP_UNREACH_TOSHOST 12 /* tos prohibited host */
187 #ifndef ICMP_UNREACH_FILTER_PROHIB
188 #define ICMP_UNREACH_FILTER_PROHIB 13 /* admin prohibited filter */
190 #ifndef ICMP_UNREACH_HOST_PRECEDENCE
191 #define ICMP_UNREACH_HOST_PRECEDENCE 14 /* host precedence violation */
193 #ifndef ICMP_UNREACH_PRECEDENCE_CUTOFF
194 #define ICMP_UNREACH_PRECEDENCE_CUTOFF 15 /* precedence cutoff */
197 /* Most of the icmp types */
198 static struct tok icmp2str[] = {
199 { ICMP_ECHOREPLY, "echo reply" },
200 { ICMP_SOURCEQUENCH, "source quench" },
201 { ICMP_ECHO, "echo request" },
202 { ICMP_ROUTERSOLICIT, "router solicitation" },
203 { ICMP_TSTAMP, "time stamp request" },
204 { ICMP_TSTAMPREPLY, "time stamp reply" },
205 { ICMP_IREQ, "information request" },
206 { ICMP_IREQREPLY, "information reply" },
207 { ICMP_MASKREQ, "address mask request" },
211 /* Formats for most of the ICMP_UNREACH codes */
212 static struct tok unreach2str[] = {
213 { ICMP_UNREACH_NET, "net %s unreachable" },
214 { ICMP_UNREACH_HOST, "host %s unreachable" },
215 { ICMP_UNREACH_SRCFAIL,
216 "%s unreachable - source route failed" },
217 { ICMP_UNREACH_NET_UNKNOWN, "net %s unreachable - unknown" },
218 { ICMP_UNREACH_HOST_UNKNOWN, "host %s unreachable - unknown" },
219 { ICMP_UNREACH_ISOLATED,
220 "%s unreachable - source host isolated" },
221 { ICMP_UNREACH_NET_PROHIB,
222 "net %s unreachable - admin prohibited" },
223 { ICMP_UNREACH_HOST_PROHIB,
224 "host %s unreachable - admin prohibited" },
225 { ICMP_UNREACH_TOSNET,
226 "net %s unreachable - tos prohibited" },
227 { ICMP_UNREACH_TOSHOST,
228 "host %s unreachable - tos prohibited" },
229 { ICMP_UNREACH_FILTER_PROHIB,
230 "host %s unreachable - admin prohibited filter" },
231 { ICMP_UNREACH_HOST_PRECEDENCE,
232 "host %s unreachable - host precedence violation" },
233 { ICMP_UNREACH_PRECEDENCE_CUTOFF,
234 "host %s unreachable - precedence cutoff" },
238 /* Formats for the ICMP_REDIRECT codes */
239 static struct tok type2str[] = {
240 { ICMP_REDIRECT_NET, "redirect %s to net %s" },
241 { ICMP_REDIRECT_HOST, "redirect %s to host %s" },
242 { ICMP_REDIRECT_TOSNET, "redirect-tos %s to net %s" },
243 { ICMP_REDIRECT_TOSHOST, "redirect-tos %s to host %s" },
248 struct mtu_discovery {
250 u_int16_t nexthopmtu;
254 struct ih_rdiscovery {
255 u_int8_t ird_addrnum;
256 u_int8_t ird_addrsiz;
257 u_int16_t ird_lifetime;
260 struct id_rdiscovery {
266 icmp_print(const u_char *bp, u_int plen, const u_char *bp2, int fragmented)
269 const struct icmp *dp;
271 const char *str, *fmt;
272 const struct ip *oip;
273 const struct udphdr *ouh;
274 u_int hlen, dport, mtu;
275 char buf[MAXHOSTNAMELEN + 100];
277 dp = (struct icmp *)bp;
278 ip = (struct ip *)bp2;
281 TCHECK(dp->icmp_code);
282 switch (dp->icmp_type) {
286 TCHECK(dp->icmp_seq);
287 (void)snprintf(buf, sizeof(buf), "echo %s seq %u",
288 dp->icmp_type == ICMP_ECHO ?
290 EXTRACT_16BITS(&dp->icmp_seq));
294 TCHECK(dp->icmp_ip.ip_dst);
295 switch (dp->icmp_code) {
297 case ICMP_UNREACH_PROTOCOL:
298 TCHECK(dp->icmp_ip.ip_p);
299 (void)snprintf(buf, sizeof(buf),
300 "%s protocol %d unreachable",
301 ipaddr_string(&dp->icmp_ip.ip_dst),
305 case ICMP_UNREACH_PORT:
306 TCHECK(dp->icmp_ip.ip_p);
308 hlen = IP_HL(oip) * 4;
309 ouh = (struct udphdr *)(((u_char *)oip) + hlen);
310 TCHECK(ouh->uh_dport);
311 dport = EXTRACT_16BITS(&ouh->uh_dport);
315 (void)snprintf(buf, sizeof(buf),
316 "%s tcp port %s unreachable",
317 ipaddr_string(&oip->ip_dst),
318 tcpport_string(dport));
322 (void)snprintf(buf, sizeof(buf),
323 "%s udp port %s unreachable",
324 ipaddr_string(&oip->ip_dst),
325 udpport_string(dport));
329 (void)snprintf(buf, sizeof(buf),
330 "%s protocol %d port %d unreachable",
331 ipaddr_string(&oip->ip_dst),
337 case ICMP_UNREACH_NEEDFRAG:
339 register const struct mtu_discovery *mp;
340 mp = (struct mtu_discovery *)&dp->icmp_void;
341 mtu = EXTRACT_16BITS(&mp->nexthopmtu);
343 (void)snprintf(buf, sizeof(buf),
344 "%s unreachable - need to frag (mtu %d)",
345 ipaddr_string(&dp->icmp_ip.ip_dst), mtu);
347 (void)snprintf(buf, sizeof(buf),
348 "%s unreachable - need to frag",
349 ipaddr_string(&dp->icmp_ip.ip_dst));
355 fmt = tok2str(unreach2str, "#%d %%s unreachable",
357 (void)snprintf(buf, sizeof(buf), fmt,
358 ipaddr_string(&dp->icmp_ip.ip_dst));
364 TCHECK(dp->icmp_ip.ip_dst);
365 fmt = tok2str(type2str, "redirect-#%d %%s to net %%s",
367 (void)snprintf(buf, sizeof(buf), fmt,
368 ipaddr_string(&dp->icmp_ip.ip_dst),
369 ipaddr_string(&dp->icmp_gwaddr));
372 case ICMP_ROUTERADVERT:
374 register const struct ih_rdiscovery *ihp;
375 register const struct id_rdiscovery *idp;
376 u_int lifetime, num, size;
378 (void)snprintf(buf, sizeof(buf), "router advertisement");
379 cp = buf + strlen(buf);
381 ihp = (struct ih_rdiscovery *)&dp->icmp_void;
383 (void)strncpy(cp, " lifetime ", sizeof(buf) - (cp - buf));
384 cp = buf + strlen(buf);
385 lifetime = EXTRACT_16BITS(&ihp->ird_lifetime);
387 (void)snprintf(cp, sizeof(buf) - (cp - buf), "%u",
389 } else if (lifetime < 60 * 60) {
390 (void)snprintf(cp, sizeof(buf) - (cp - buf), "%u:%02u",
391 lifetime / 60, lifetime % 60);
393 (void)snprintf(cp, sizeof(buf) - (cp - buf),
396 (lifetime % 3600) / 60,
399 cp = buf + strlen(buf);
401 num = ihp->ird_addrnum;
402 (void)snprintf(cp, sizeof(buf) - (cp - buf), " %d:", num);
403 cp = buf + strlen(buf);
405 size = ihp->ird_addrsiz;
407 (void)snprintf(cp, sizeof(buf) - (cp - buf),
411 idp = (struct id_rdiscovery *)&dp->icmp_data;
414 (void)snprintf(cp, sizeof(buf) - (cp - buf), " {%s %u}",
415 ipaddr_string(&idp->ird_addr),
416 EXTRACT_32BITS(&idp->ird_pref));
417 cp = buf + strlen(buf);
424 TCHECK(dp->icmp_ip.ip_dst);
425 switch (dp->icmp_code) {
427 case ICMP_TIMXCEED_INTRANS:
428 str = "time exceeded in-transit";
431 case ICMP_TIMXCEED_REASS:
432 str = "ip reassembly time exceeded";
436 (void)snprintf(buf, sizeof(buf), "time exceeded-#%d",
444 (void)snprintf(buf, sizeof(buf),
445 "parameter problem - code %d", dp->icmp_code);
447 TCHECK(dp->icmp_pptr);
448 (void)snprintf(buf, sizeof(buf),
449 "parameter problem - octet %d", dp->icmp_pptr);
454 TCHECK(dp->icmp_mask);
455 (void)snprintf(buf, sizeof(buf), "address mask is 0x%08x",
456 EXTRACT_32BITS(&dp->icmp_mask));
460 TCHECK(dp->icmp_seq);
461 (void)snprintf(buf, sizeof(buf),
462 "time stamp query id %u seq %u",
463 EXTRACT_16BITS(&dp->icmp_id),
464 EXTRACT_16BITS(&dp->icmp_seq));
467 case ICMP_TSTAMPREPLY:
468 TCHECK(dp->icmp_ttime);
469 (void)snprintf(buf, sizeof(buf),
470 "time stamp reply id %u seq %u : org 0x%x recv 0x%x xmit 0x%x",
471 EXTRACT_16BITS(&dp->icmp_id),
472 EXTRACT_16BITS(&dp->icmp_seq),
473 EXTRACT_32BITS(&dp->icmp_otime),
474 EXTRACT_32BITS(&dp->icmp_rtime),
475 EXTRACT_32BITS(&dp->icmp_ttime));
479 str = tok2str(icmp2str, "type-#%d", dp->icmp_type);
482 (void)printf("icmp %d: %s", plen, str);
483 if (vflag && !fragmented) { /* don't attempt checksumming if this is a frag */
484 u_int16_t sum, icmp_sum;
485 if (TTEST2(*bp, plen)) {
486 sum = in_cksum((u_short*)dp, plen, 0);
488 icmp_sum = EXTRACT_16BITS(&dp->icmp_cksum);
489 (void)printf(" (wrong icmp cksum %x (->%x)!)",
491 in_cksum_shouldbe(icmp_sum, sum));
495 if (vflag > 1 && !ICMP_INFOTYPE(dp->icmp_type)) {
497 (void)printf(" for ");
498 ip = (struct ip *)bp;
499 snaplen = snapend - bp;
500 ip_print(bp, EXTRACT_16BITS(&ip->ip_len));
504 fputs("[|icmp]", stdout);