xref: /freebsd/contrib/tcpdump/print-igmp.c (revision 62cfcf62f627e5093fb37026a6d8c98e4d2ef04c)
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 Group Management Protocol (IGMP) printer */
23 
24 #ifdef HAVE_CONFIG_H
25 #include "config.h"
26 #endif
27 
28 #include <netdissect-stdinc.h>
29 
30 #include "netdissect.h"
31 #include "addrtoname.h"
32 #include "extract.h"
33 
34 #ifndef IN_CLASSD
35 #define IN_CLASSD(i) (((int32_t)(i) & 0xf0000000) == 0xe0000000)
36 #endif
37 
38 static const char tstr[] = "[|igmp]";
39 
40 /* (following from ipmulti/mrouted/prune.h) */
41 
42 /*
43  * The packet format for a traceroute request.
44  */
45 struct tr_query {
46     uint32_t  tr_src;          /* traceroute source */
47     uint32_t  tr_dst;          /* traceroute destination */
48     uint32_t  tr_raddr;        /* traceroute response address */
49     uint32_t  tr_rttlqid;      /* response ttl and qid */
50 };
51 
52 #define TR_GETTTL(x)        (int)(((x) >> 24) & 0xff)
53 #define TR_GETQID(x)        ((x) & 0x00ffffff)
54 
55 /*
56  * Traceroute response format.  A traceroute response has a tr_query at the
57  * beginning, followed by one tr_resp for each hop taken.
58  */
59 struct tr_resp {
60     uint32_t tr_qarr;          /* query arrival time */
61     uint32_t tr_inaddr;        /* incoming interface address */
62     uint32_t tr_outaddr;       /* outgoing interface address */
63     uint32_t tr_rmtaddr;       /* parent address in source tree */
64     uint32_t tr_vifin;         /* input packet count on interface */
65     uint32_t tr_vifout;        /* output packet count on interface */
66     uint32_t tr_pktcnt;        /* total incoming packets for src-grp */
67     uint8_t  tr_rproto;      /* routing proto deployed on router */
68     uint8_t  tr_fttl;        /* ttl required to forward on outvif */
69     uint8_t  tr_smask;       /* subnet mask for src addr */
70     uint8_t  tr_rflags;      /* forwarding error codes */
71 };
72 
73 /* defs within mtrace */
74 #define TR_QUERY 1
75 #define TR_RESP 2
76 
77 /* fields for tr_rflags (forwarding error codes) */
78 #define TR_NO_ERR   0
79 #define TR_WRONG_IF 1
80 #define TR_PRUNED   2
81 #define TR_OPRUNED  3
82 #define TR_SCOPED   4
83 #define TR_NO_RTE   5
84 #define TR_NO_FWD   7
85 #define TR_NO_SPACE 0x81
86 #define TR_OLD_ROUTER   0x82
87 
88 /* fields for tr_rproto (routing protocol) */
89 #define TR_PROTO_DVMRP  1
90 #define TR_PROTO_MOSPF  2
91 #define TR_PROTO_PIM    3
92 #define TR_PROTO_CBT    4
93 
94 /* igmpv3 report types */
95 static const struct tok igmpv3report2str[] = {
96 	{ 1,	"is_in" },
97 	{ 2,	"is_ex" },
98 	{ 3,	"to_in" },
99 	{ 4,	"to_ex" },
100 	{ 5,	"allow" },
101 	{ 6,	"block" },
102 	{ 0,	NULL }
103 };
104 
105 static void
106 print_mtrace(netdissect_options *ndo,
107              register const u_char *bp, register u_int len)
108 {
109     register const struct tr_query *tr = (const struct tr_query *)(bp + 8);
110 
111     ND_TCHECK(*tr);
112     if (len < 8 + sizeof (struct tr_query)) {
113 	ND_PRINT((ndo, " [invalid len %d]", len));
114 	return;
115     }
116     ND_PRINT((ndo, "mtrace %u: %s to %s reply-to %s",
117         TR_GETQID(EXTRACT_32BITS(&tr->tr_rttlqid)),
118         ipaddr_string(ndo, &tr->tr_src), ipaddr_string(ndo, &tr->tr_dst),
119         ipaddr_string(ndo, &tr->tr_raddr)));
120     if (IN_CLASSD(EXTRACT_32BITS(&tr->tr_raddr)))
121         ND_PRINT((ndo, " with-ttl %d", TR_GETTTL(EXTRACT_32BITS(&tr->tr_rttlqid))));
122     return;
123 trunc:
124     ND_PRINT((ndo, "%s", tstr));
125 }
126 
127 static void
128 print_mresp(netdissect_options *ndo,
129             register const u_char *bp, register u_int len)
130 {
131     register const struct tr_query *tr = (const struct tr_query *)(bp + 8);
132 
133     ND_TCHECK(*tr);
134     if (len < 8 + sizeof (struct tr_query)) {
135 	ND_PRINT((ndo, " [invalid len %d]", len));
136 	return;
137     }
138     ND_PRINT((ndo, "mresp %lu: %s to %s reply-to %s",
139         (u_long)TR_GETQID(EXTRACT_32BITS(&tr->tr_rttlqid)),
140         ipaddr_string(ndo, &tr->tr_src), ipaddr_string(ndo, &tr->tr_dst),
141         ipaddr_string(ndo, &tr->tr_raddr)));
142     if (IN_CLASSD(EXTRACT_32BITS(&tr->tr_raddr)))
143         ND_PRINT((ndo, " with-ttl %d", TR_GETTTL(EXTRACT_32BITS(&tr->tr_rttlqid))));
144     return;
145 trunc:
146     ND_PRINT((ndo, "%s", tstr));
147 }
148 
149 static void
150 print_igmpv3_report(netdissect_options *ndo,
151                     register const u_char *bp, register u_int len)
152 {
153     u_int group, nsrcs, ngroups;
154     register u_int i, j;
155 
156     /* Minimum len is 16, and should be a multiple of 4 */
157     if (len < 16 || len & 0x03) {
158 	ND_PRINT((ndo, " [invalid len %d]", len));
159 	return;
160     }
161     ND_TCHECK2(bp[6], 2);
162     ngroups = EXTRACT_16BITS(&bp[6]);
163     ND_PRINT((ndo, ", %d group record(s)", ngroups));
164     if (ndo->ndo_vflag > 0) {
165 	/* Print the group records */
166 	group = 8;
167         for (i=0; i<ngroups; i++) {
168 	    if (len < group+8) {
169 		ND_PRINT((ndo, " [invalid number of groups]"));
170 		return;
171 	    }
172 	    ND_TCHECK2(bp[group+4], 4);
173             ND_PRINT((ndo, " [gaddr %s", ipaddr_string(ndo, &bp[group+4])));
174 	    ND_PRINT((ndo, " %s", tok2str(igmpv3report2str, " [v3-report-#%d]",
175 								bp[group])));
176             nsrcs = EXTRACT_16BITS(&bp[group+2]);
177 	    /* Check the number of sources and print them */
178 	    if (len < group+8+(nsrcs<<2)) {
179 		ND_PRINT((ndo, " [invalid number of sources %d]", nsrcs));
180 		return;
181 	    }
182             if (ndo->ndo_vflag == 1)
183                 ND_PRINT((ndo, ", %d source(s)", nsrcs));
184             else {
185 		/* Print the sources */
186                 ND_PRINT((ndo, " {"));
187                 for (j=0; j<nsrcs; j++) {
188 		    ND_TCHECK2(bp[group+8+(j<<2)], 4);
189 		    ND_PRINT((ndo, " %s", ipaddr_string(ndo, &bp[group+8+(j<<2)])));
190 		}
191                 ND_PRINT((ndo, " }"));
192             }
193 	    /* Next group record */
194             group += 8 + (nsrcs << 2);
195 	    ND_PRINT((ndo, "]"));
196         }
197     }
198     return;
199 trunc:
200     ND_PRINT((ndo, "%s", tstr));
201 }
202 
203 static void
204 print_igmpv3_query(netdissect_options *ndo,
205                    register const u_char *bp, register u_int len)
206 {
207     u_int mrc;
208     u_int mrt;
209     u_int nsrcs;
210     register u_int i;
211 
212     ND_PRINT((ndo, " v3"));
213     /* Minimum len is 12, and should be a multiple of 4 */
214     if (len < 12 || len & 0x03) {
215 	ND_PRINT((ndo, " [invalid len %d]", len));
216 	return;
217     }
218     ND_TCHECK(bp[1]);
219     mrc = bp[1];
220     if (mrc < 128) {
221 	mrt = mrc;
222     } else {
223         mrt = ((mrc & 0x0f) | 0x10) << (((mrc & 0x70) >> 4) + 3);
224     }
225     if (mrc != 100) {
226 	ND_PRINT((ndo, " [max resp time "));
227         if (mrt < 600) {
228             ND_PRINT((ndo, "%.1fs", mrt * 0.1));
229         } else {
230             unsigned_relts_print(ndo, mrt / 10);
231         }
232 	ND_PRINT((ndo, "]"));
233     }
234     ND_TCHECK2(bp[4], 4);
235     if (EXTRACT_32BITS(&bp[4]) == 0)
236 	return;
237     ND_PRINT((ndo, " [gaddr %s", ipaddr_string(ndo, &bp[4])));
238     ND_TCHECK2(bp[10], 2);
239     nsrcs = EXTRACT_16BITS(&bp[10]);
240     if (nsrcs > 0) {
241 	if (len < 12 + (nsrcs << 2))
242 	    ND_PRINT((ndo, " [invalid number of sources]"));
243 	else if (ndo->ndo_vflag > 1) {
244 	    ND_PRINT((ndo, " {"));
245 	    for (i=0; i<nsrcs; i++) {
246 		ND_TCHECK2(bp[12+(i<<2)], 4);
247 		ND_PRINT((ndo, " %s", ipaddr_string(ndo, &bp[12+(i<<2)])));
248 	    }
249 	    ND_PRINT((ndo, " }"));
250 	} else
251 	    ND_PRINT((ndo, ", %d source(s)", nsrcs));
252     }
253     ND_PRINT((ndo, "]"));
254     return;
255 trunc:
256     ND_PRINT((ndo, "%s", tstr));
257 }
258 
259 void
260 igmp_print(netdissect_options *ndo,
261            register const u_char *bp, register u_int len)
262 {
263     struct cksum_vec vec[1];
264 
265     if (ndo->ndo_qflag) {
266         ND_PRINT((ndo, "igmp"));
267         return;
268     }
269 
270     ND_TCHECK(bp[0]);
271     switch (bp[0]) {
272     case 0x11:
273         ND_PRINT((ndo, "igmp query"));
274 	if (len >= 12)
275 	    print_igmpv3_query(ndo, bp, len);
276 	else {
277             ND_TCHECK(bp[1]);
278 	    if (bp[1]) {
279 		ND_PRINT((ndo, " v2"));
280 		if (bp[1] != 100)
281 		    ND_PRINT((ndo, " [max resp time %d]", bp[1]));
282 	    } else
283 		ND_PRINT((ndo, " v1"));
284             ND_TCHECK2(bp[4], 4);
285 	    if (EXTRACT_32BITS(&bp[4]))
286                 ND_PRINT((ndo, " [gaddr %s]", ipaddr_string(ndo, &bp[4])));
287             if (len != 8)
288                 ND_PRINT((ndo, " [len %d]", len));
289 	}
290         break;
291     case 0x12:
292         ND_TCHECK2(bp[4], 4);
293         ND_PRINT((ndo, "igmp v1 report %s", ipaddr_string(ndo, &bp[4])));
294         if (len != 8)
295             ND_PRINT((ndo, " [len %d]", len));
296         break;
297     case 0x16:
298         ND_TCHECK2(bp[4], 4);
299         ND_PRINT((ndo, "igmp v2 report %s", ipaddr_string(ndo, &bp[4])));
300         break;
301     case 0x22:
302         ND_PRINT((ndo, "igmp v3 report"));
303 	print_igmpv3_report(ndo, bp, len);
304         break;
305     case 0x17:
306         ND_TCHECK2(bp[4], 4);
307         ND_PRINT((ndo, "igmp leave %s", ipaddr_string(ndo, &bp[4])));
308         break;
309     case 0x13:
310         ND_PRINT((ndo, "igmp dvmrp"));
311         if (len < 8)
312             ND_PRINT((ndo, " [len %d]", len));
313         else
314             dvmrp_print(ndo, bp, len);
315         break;
316     case 0x14:
317         ND_PRINT((ndo, "igmp pimv1"));
318         pimv1_print(ndo, bp, len);
319         break;
320     case 0x1e:
321         print_mresp(ndo, bp, len);
322         break;
323     case 0x1f:
324         print_mtrace(ndo, bp, len);
325         break;
326     default:
327         ND_PRINT((ndo, "igmp-%d", bp[0]));
328         break;
329     }
330 
331     if (ndo->ndo_vflag && len >= 4 && ND_TTEST2(bp[0], len)) {
332         /* Check the IGMP checksum */
333         vec[0].ptr = bp;
334         vec[0].len = len;
335         if (in_cksum(vec, 1))
336             ND_PRINT((ndo, " bad igmp cksum %x!", EXTRACT_16BITS(&bp[2])));
337     }
338     return;
339 trunc:
340     ND_PRINT((ndo, "%s", tstr));
341 }
342