xref: /openbsd-src/usr.sbin/tcpdump/print-icmp.c (revision 62a742911104f98b9185b2c6b6007d9b1c36396c)
1 /*
2  * Copyright (c) 1988, 1989, 1990, 1991, 1993, 1994, 1995, 1996
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that: (1) source code distributions
7  * retain the above copyright notice and this paragraph in its entirety, (2)
8  * distributions including binary code include the above copyright notice and
9  * this paragraph in its entirety in the documentation or other materials
10  * provided with the distribution, and (3) all advertising materials mentioning
11  * features or use of this software display the following acknowledgement:
12  * ``This product includes software developed by the University of California,
13  * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
14  * the University nor the names of its contributors may be used to endorse
15  * or promote products derived from this software without specific prior
16  * written permission.
17  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
18  * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
19  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
20  */
21 
22 #ifndef lint
23 static const char rcsid[] =
24     "@(#) $Header: /home/cvs/src/usr.sbin/tcpdump/print-icmp.c,v 1.7 1998/07/13 22:13:47 deraadt Exp $ (LBL)";
25 #endif
26 
27 #include <sys/param.h>
28 #include <sys/time.h>
29 #include <sys/socket.h>
30 
31 #ifdef __STDC__
32 struct mbuf;
33 struct rtentry;
34 #endif
35 #include <net/if.h>
36 
37 #include <netinet/in.h>
38 #include <netinet/if_ether.h>
39 #include <netinet/in_systm.h>
40 #include <netinet/ip.h>
41 #include <netinet/ip_icmp.h>
42 #include <netinet/ip_var.h>
43 #include <netinet/udp.h>
44 #include <netinet/udp_var.h>
45 #include <netinet/tcp.h>
46 #include <netinet/tcpip.h>
47 
48 #include <stdio.h>
49 #include <string.h>
50 
51 #include "interface.h"
52 #include "addrtoname.h"
53 #include "extract.h"			/* must come after interface.h */
54 
55 /* rfc1700 */
56 #ifndef ICMP_UNREACH_NET_UNKNOWN
57 #define ICMP_UNREACH_NET_UNKNOWN	6	/* destination net unknown */
58 #endif
59 #ifndef ICMP_UNREACH_HOST_UNKNOWN
60 #define ICMP_UNREACH_HOST_UNKNOWN	7	/* destination host unknown */
61 #endif
62 #ifndef ICMP_UNREACH_ISOLATED
63 #define ICMP_UNREACH_ISOLATED		8	/* source host isolated */
64 #endif
65 #ifndef ICMP_UNREACH_NET_PROHIB
66 #define ICMP_UNREACH_NET_PROHIB		9	/* admin prohibited net */
67 #endif
68 #ifndef ICMP_UNREACH_HOST_PROHIB
69 #define ICMP_UNREACH_HOST_PROHIB	10	/* admin prohibited host */
70 #endif
71 #ifndef ICMP_UNREACH_TOSNET
72 #define ICMP_UNREACH_TOSNET		11	/* tos prohibited net */
73 #endif
74 #ifndef ICMP_UNREACH_TOSHOST
75 #define ICMP_UNREACH_TOSHOST		12	/* tos prohibited host */
76 #endif
77 
78 /* rfc1716 */
79 #ifndef ICMP_UNREACH_FILTER_PROHIB
80 #define ICMP_UNREACH_FILTER_PROHIB	13	/* admin prohibited filter */
81 #endif
82 #ifndef ICMP_UNREACH_HOST_PRECEDENCE
83 #define ICMP_UNREACH_HOST_PRECEDENCE	14	/* host precedence violation */
84 #endif
85 #ifndef ICMP_UNREACH_PRECEDENCE_CUTOFF
86 #define ICMP_UNREACH_PRECEDENCE_CUTOFF	15	/* precedence cutoff */
87 #endif
88 
89 /* rfc1256 */
90 #ifndef ICMP_ROUTERADVERT
91 #define ICMP_ROUTERADVERT		9	/* router advertisement */
92 #endif
93 #ifndef ICMP_ROUTERSOLICIT
94 #define ICMP_ROUTERSOLICIT		10	/* router solicitation */
95 #endif
96 
97 /* Most of the icmp types */
98 static struct tok icmp2str[] = {
99 	{ ICMP_ECHOREPLY,		"echo reply" },
100 	{ ICMP_SOURCEQUENCH,		"source quench" },
101 	{ ICMP_ECHO,			"echo request" },
102 	{ ICMP_ROUTERSOLICIT,		"router solicitation" },
103 	{ ICMP_TSTAMP,			"time stamp request" },
104 	{ ICMP_TSTAMPREPLY,		"time stamp reply" },
105 	{ ICMP_IREQ,			"information request" },
106 	{ ICMP_IREQREPLY,		"information reply" },
107 	{ ICMP_MASKREQ,			"address mask request" },
108 	{ 0,				NULL }
109 };
110 
111 /* Formats for most of the ICMP_UNREACH codes */
112 static struct tok unreach2str[] = {
113 	{ ICMP_UNREACH_NET,		"net %s unreachable" },
114 	{ ICMP_UNREACH_HOST,		"host %s unreachable" },
115 	{ ICMP_UNREACH_SRCFAIL,
116 	    "%s unreachable - source route failed" },
117 	{ ICMP_UNREACH_NET_UNKNOWN,	"net %s unreachable - unknown" },
118 	{ ICMP_UNREACH_HOST_UNKNOWN,	"host %s unreachable - unknown" },
119 	{ ICMP_UNREACH_ISOLATED,
120 	    "%s unreachable - source host isolated" },
121 	{ ICMP_UNREACH_NET_PROHIB,
122 	    "net %s unreachable - admin prohibited" },
123 	{ ICMP_UNREACH_HOST_PROHIB,
124 	    "host %s unreachable - admin prohibited" },
125 	{ ICMP_UNREACH_TOSNET,
126 	    "net %s unreachable - tos prohibited" },
127 	{ ICMP_UNREACH_TOSHOST,
128 	    "host %s unreachable - tos prohibited" },
129 	{ ICMP_UNREACH_FILTER_PROHIB,
130 	    "host %s unreachable - admin prohibited filter" },
131 	{ ICMP_UNREACH_HOST_PRECEDENCE,
132 	    "host %s unreachable - host precedence violation" },
133 	{ ICMP_UNREACH_PRECEDENCE_CUTOFF,
134 	    "host %s unreachable - precedence cutoff" },
135 	{ 0,				NULL }
136 };
137 
138 /* Formats for the ICMP_REDIRECT codes */
139 static struct tok type2str[] = {
140 	{ ICMP_REDIRECT_NET,		"redirect %s to net %s" },
141 	{ ICMP_REDIRECT_HOST,		"redirect %s to host %s" },
142 	{ ICMP_REDIRECT_TOSNET,		"redirect-tos %s to net %s" },
143 	{ ICMP_REDIRECT_TOSHOST,	"redirect-tos %s to net %s" },
144 	{ 0,				NULL }
145 };
146 
147 /* rfc1191 */
148 struct mtu_discovery {
149 	short unused;
150 	short nexthopmtu;
151 };
152 
153 /* rfc1256 */
154 struct ih_rdiscovery {
155 	u_char ird_addrnum;
156 	u_char ird_addrsiz;
157 	u_short ird_lifetime;
158 };
159 
160 struct id_rdiscovery {
161 	u_int32_t ird_addr;
162 	u_int32_t ird_pref;
163 };
164 
165 void
166 icmp_print(register const u_char *bp, register const u_char *bp2)
167 {
168 	register char *cp;
169 	register const struct icmp *dp;
170 	register const struct ip *ip;
171 	register const char *str, *fmt;
172 	register const struct ip *oip;
173 	register const struct udphdr *ouh;
174 	register u_int hlen, dport, mtu;
175 	char buf[MAXHOSTNAMELEN+256];
176 
177 	dp = (struct icmp *)bp;
178 	ip = (struct ip *)bp2;
179 	str = buf;
180 
181         (void)printf("%s > %s: ",
182 		ipaddr_string(&ip->ip_src),
183 		ipaddr_string(&ip->ip_dst));
184 
185 	TCHECK(dp->icmp_code);
186 	switch (dp->icmp_type) {
187 
188 	case ICMP_UNREACH:
189 		TCHECK(dp->icmp_ip.ip_dst);
190 		switch (dp->icmp_code) {
191 
192 		case ICMP_UNREACH_PROTOCOL:
193 			TCHECK(dp->icmp_ip.ip_p);
194 			(void)snprintf(buf, sizeof buf,
195 				       "%s protocol %d unreachable",
196 				       ipaddr_string(&dp->icmp_ip.ip_dst),
197 				       dp->icmp_ip.ip_p);
198 			break;
199 
200 		case ICMP_UNREACH_PORT:
201 			TCHECK(dp->icmp_ip.ip_p);
202 			oip = &dp->icmp_ip;
203 			hlen = oip->ip_hl * 4;
204 			ouh = (struct udphdr *)(((u_char *)oip) + hlen);
205 			dport = ntohs(ouh->uh_dport);
206 			switch (oip->ip_p) {
207 
208 			case IPPROTO_TCP:
209 				(void)snprintf(buf, sizeof buf,
210 					"%s tcp port %s unreachable",
211 					ipaddr_string(&oip->ip_dst),
212 					tcpport_string(dport));
213 				break;
214 
215 			case IPPROTO_UDP:
216 				(void)snprintf(buf, sizeof buf,
217 					"%s udp port %s unreachable",
218 					ipaddr_string(&oip->ip_dst),
219 					udpport_string(dport));
220 				break;
221 
222 			default:
223 				(void)snprintf(buf, sizeof buf,
224 					"%s protocol %d port %d unreachable",
225 					ipaddr_string(&oip->ip_dst),
226 					oip->ip_p, dport);
227 				break;
228 			}
229 			break;
230 
231 		case ICMP_UNREACH_NEEDFRAG:
232 			{
233 			register const struct mtu_discovery *mp;
234 
235 			mp = (struct mtu_discovery *)&dp->icmp_void;
236                         mtu = EXTRACT_16BITS(&mp->nexthopmtu);
237                         if (mtu)
238 			    (void)snprintf(buf, sizeof buf,
239 				"%s unreachable - need to frag (mtu %d)",
240 				ipaddr_string(&dp->icmp_ip.ip_dst), mtu);
241                         else
242 			    (void)snprintf(buf, sizeof buf,
243 				"%s unreachable - need to frag",
244 				ipaddr_string(&dp->icmp_ip.ip_dst));
245 			}
246 			break;
247 
248 		default:
249 			fmt = tok2str(unreach2str, "#%d %%s unreachable",
250 			    dp->icmp_code);
251 			(void)snprintf(buf, sizeof buf, fmt,
252 			    ipaddr_string(&dp->icmp_ip.ip_dst));
253 			break;
254 		}
255 		break;
256 
257 	case ICMP_REDIRECT:
258 		TCHECK(dp->icmp_ip.ip_dst);
259 		fmt = tok2str(type2str, "redirect-#%d %%s to net %%s",
260 		    dp->icmp_code);
261 		(void)snprintf(buf, sizeof buf, fmt,
262 		    ipaddr_string(&dp->icmp_ip.ip_dst),
263 		    ipaddr_string(&dp->icmp_gwaddr));
264 		break;
265 
266 	case ICMP_ROUTERADVERT:
267 		{
268 		register const struct ih_rdiscovery *ihp;
269 		register const struct id_rdiscovery *idp;
270 		u_int lifetime, num, size;
271 
272 		(void)strncpy(buf, "router advertisement", sizeof buf-1);
273 		buf[sizeof buf-1] = '\0';
274 		cp = buf + strlen(buf);
275 
276 		ihp = (struct ih_rdiscovery *)&dp->icmp_void;
277 		TCHECK(*ihp);
278 		(void)strcpy(cp, " lifetime ");
279 		cp = buf + strlen(buf);
280 		lifetime = EXTRACT_16BITS(&ihp->ird_lifetime);
281 		if (lifetime < 60)
282 			(void)snprintf(cp, buf + sizeof buf - cp, "%u", lifetime);
283 		else if (lifetime < 60 * 60)
284 			(void)snprintf(cp, buf + sizeof buf - cp, "%u:%02u",
285 			    lifetime / 60, lifetime % 60);
286 		else
287 			(void)snprintf(cp, buf + sizeof buf - cp, "%u:%02u:%02u",
288 			    lifetime / 3600,
289 			    (lifetime % 3600) / 60,
290 			    lifetime % 60);
291 		cp = buf + strlen(buf);
292 
293 		num = ihp->ird_addrnum;
294 		(void)snprintf(cp, buf + sizeof buf - cp, " %d:", num);
295 		cp = buf + strlen(buf);
296 
297 		size = ihp->ird_addrsiz;
298 		if (size != 2) {
299 			(void)snprintf(cp, buf - sizeof buf - cp,
300 				" [size %d]", size);
301 			break;
302 		}
303 		idp = (struct id_rdiscovery *)&dp->icmp_data;
304 		while (num-- > 0) {
305 			TCHECK(*idp);
306 			(void)snprintf(cp, buf + sizeof buf - cp, " {%s %u}",
307 			    ipaddr_string(&idp->ird_addr),
308 			    EXTRACT_32BITS(&idp->ird_pref));
309 			cp = buf + strlen(buf);
310 		}
311 		}
312 		break;
313 
314 	case ICMP_TIMXCEED:
315 		TCHECK(dp->icmp_ip.ip_dst);
316 		switch (dp->icmp_code) {
317 
318 		case ICMP_TIMXCEED_INTRANS:
319 			str = "time exceeded in-transit";
320 			break;
321 
322 		case ICMP_TIMXCEED_REASS:
323 			str = "ip reassembly time exceeded";
324 			break;
325 
326 		default:
327 			(void)snprintf(buf, sizeof buf,
328 				"time exceeded-#%d", dp->icmp_code);
329 			break;
330 		}
331 		break;
332 
333 	case ICMP_PARAMPROB:
334 		if (dp->icmp_code)
335 			(void)snprintf(buf, sizeof buf,
336 				"parameter problem - code %d",
337 				dp->icmp_code);
338 		else {
339 			TCHECK(dp->icmp_pptr);
340 			(void)snprintf(buf, sizeof buf,
341 				"parameter problem - octet %d",
342 				dp->icmp_pptr);
343 		}
344 		break;
345 
346 	case ICMP_MASKREPLY:
347 		TCHECK(dp->icmp_mask);
348 		(void)snprintf(buf, sizeof buf, "address mask is 0x%08x",
349 		    (u_int32_t)ntohl(dp->icmp_mask));
350 		break;
351 
352 	default:
353 		str = tok2str(icmp2str, "type-#%d", dp->icmp_type);
354 		break;
355 	}
356         (void)printf("icmp: %s", str);
357 	return;
358 trunc:
359 	fputs("[|icmp]", stdout);
360 }
361