print-igmp.c revision 75115 
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
23static const char rcsid[] =
24    "@(#) $Header: /tcpdump/master/tcpdump/print-igmp.c,v 1.3 2001/01/09 08:01:18 fenner Exp $ (LBL)";
25#endif
26
27#ifdef HAVE_CONFIG_H
28#include "config.h"
29#endif
30
31#include <sys/param.h>
32#include <sys/socket.h>
33
34#include <netinet/in.h>
35#include <netinet/in_systm.h>
36#include <netinet/ip.h>
37
38#include <stdio.h>
39#include <string.h>
40
41#include "interface.h"
42#include "addrtoname.h"
43#include "extract.h"            /* must come after interface.h */
44
45#ifndef IN_CLASSD
46#define IN_CLASSD(i) (((int32_t)(i) & 0xf0000000) == 0xe0000000)
47#endif
48
49/* (following from ipmulti/mrouted/prune.h) */
50
51/*
52 * The packet format for a traceroute request.
53 */
54struct tr_query {
55    u_int  tr_src;          /* traceroute source */
56    u_int  tr_dst;          /* traceroute destination */
57    u_int  tr_raddr;        /* traceroute response address */
58    u_int  tr_rttlqid;      /* response ttl and qid */
59};
60
61#define TR_GETTTL(x)        (int)(((x) >> 24) & 0xff)
62#define TR_GETQID(x)        ((x) & 0x00ffffff)
63
64/*
65 * Traceroute response format.  A traceroute response has a tr_query at the
66 * beginning, followed by one tr_resp for each hop taken.
67 */
68struct tr_resp {
69    u_int tr_qarr;          /* query arrival time */
70    u_int tr_inaddr;        /* incoming interface address */
71    u_int tr_outaddr;       /* outgoing interface address */
72    u_int tr_rmtaddr;       /* parent address in source tree */
73    u_int tr_vifin;         /* input packet count on interface */
74    u_int tr_vifout;        /* output packet count on interface */
75    u_int tr_pktcnt;        /* total incoming packets for src-grp */
76    u_char  tr_rproto;      /* routing proto deployed on router */
77    u_char  tr_fttl;        /* ttl required to forward on outvif */
78    u_char  tr_smask;       /* subnet mask for src addr */
79    u_char  tr_rflags;      /* forwarding error codes */
80};
81
82/* defs within mtrace */
83#define TR_QUERY 1
84#define TR_RESP 2
85
86/* fields for tr_rflags (forwarding error codes) */
87#define TR_NO_ERR   0
88#define TR_WRONG_IF 1
89#define TR_PRUNED   2
90#define TR_OPRUNED  3
91#define TR_SCOPED   4
92#define TR_NO_RTE   5
93#define TR_NO_FWD   7
94#define TR_NO_SPACE 0x81
95#define TR_OLD_ROUTER   0x82
96
97/* fields for tr_rproto (routing protocol) */
98#define TR_PROTO_DVMRP  1
99#define TR_PROTO_MOSPF  2
100#define TR_PROTO_PIM    3
101#define TR_PROTO_CBT    4
102
103/* igmpv3 report types */
104static struct tok igmpv3report2str[] = {
105	{ 1,	"is_in" },
106	{ 2,	"is_ex" },
107	{ 3,	"to_in" },
108	{ 4,	"to_ex" },
109	{ 5,	"allow" },
110	{ 6,	"block" },
111	{ 0,	NULL }
112};
113
114static void
115print_mtrace(register const u_char *bp, register u_int len)
116{
117    register struct tr_query *tr = (struct tr_query *)(bp + 8);
118
119    printf("mtrace %lu: %s to %s reply-to %s",
120        (u_long)TR_GETQID(ntohl(tr->tr_rttlqid)),
121        ipaddr_string(&tr->tr_src), ipaddr_string(&tr->tr_dst),
122        ipaddr_string(&tr->tr_raddr));
123    if (IN_CLASSD(ntohl(tr->tr_raddr)))
124        printf(" with-ttl %d", TR_GETTTL(ntohl(tr->tr_rttlqid)));
125}
126
127static void
128print_mresp(register const u_char *bp, register u_int len)
129{
130    register struct tr_query *tr = (struct tr_query *)(bp + 8);
131
132    printf("mresp %lu: %s to %s reply-to %s",
133        (u_long)TR_GETQID(ntohl(tr->tr_rttlqid)),
134        ipaddr_string(&tr->tr_src), ipaddr_string(&tr->tr_dst),
135        ipaddr_string(&tr->tr_raddr));
136    if (IN_CLASSD(ntohl(tr->tr_raddr)))
137        printf(" with-ttl %d", TR_GETTTL(ntohl(tr->tr_rttlqid)));
138}
139
140static void
141print_igmpv3_report(register const u_char *bp, register u_int len,
142       register const u_char *bp2)
143{
144    int group, nsrcs, ngroups;
145    register int i, j;
146
147    /* Minimum len is 16, and should be a multiple of 4 */
148    if (len < 16 || len & 0x03) {
149    	(void)printf(" [invalid len %d]", len);
150    	return;
151    }
152    TCHECK2(bp[6], 2);
153    ngroups = EXTRACT_16BITS(&bp[6]);
154    (void)printf(", %d group record(s)", ngroups);
155    if (vflag > 0) {
156	/* Print the group records */
157    	group = 8;
158        for (i=0; i<ngroups; i++) {
159	    if (len < group+8) {
160		(void)printf(" [invalid number of groups]");
161		return;
162	    }
163	    TCHECK2(bp[group+4], 4);
164            (void)printf(" [gaddr %s", ipaddr_string(&bp[group+4]));
165	    (void)printf(" %s", tok2str(igmpv3report2str, " [v3-report-#%d]",
166								bp[group]));
167            nsrcs = EXTRACT_16BITS(&bp[group+2]);
168	    /* Check the number of sources and print them */
169	    if (len < group+8+(nsrcs<<2)) {
170		(void)printf(" [invalid number of sources %d]", nsrcs);
171		return;
172	    }
173            if (vflag == 1)
174                (void)printf(", %d source(s)", nsrcs);
175            else {
176		/* Print the sources */
177                (void)printf(" {");
178                for (j=0; j<nsrcs; j++) {
179		    TCHECK2(bp[group+8+(j<<2)], 4);
180		    (void)printf(" %s", ipaddr_string(&bp[group+8+(j<<2)]));
181		}
182                (void)printf(" }");
183            }
184	    /* Next group record */
185            group += 8 + (nsrcs << 2);
186	    (void)printf("]");
187        }
188    }
189    return;
190trunc:
191    (void)printf("[|igmp]");
192    return;
193}
194
195static void
196print_igmpv3_query(register const u_char *bp, register u_int len,
197       register const u_char *bp2)
198{
199    int nsrcs;
200    register int i;
201
202    (void)printf(" v3");
203    /* Minimum len is 12, and should be a multiple of 4 */
204    if (len < 12 || len & 0x03) {
205    	(void)printf(" [invalid len %d]", len);
206    	return;
207    }
208    TCHECK2(bp[4], 4);
209    if (EXTRACT_32BITS(&bp[4]) == 0)
210	return;
211    (void)printf(" [gaddr %s", ipaddr_string(&bp[4]));
212    TCHECK2(bp[10], 2);
213    nsrcs = EXTRACT_16BITS(&bp[10]);
214    if (nsrcs > 0) {
215	if (len < 12 + (nsrcs << 2))
216	    (void)printf(" [invalid number of sources]");
217	else if (vflag > 1) {
218	    (void)printf(" {");
219	    for (i=0; i<nsrcs; i++) {
220		TCHECK2(bp[12+(i<<2)], 4);
221		(void)printf(" %s", ipaddr_string(&bp[12+(i<<2)]));
222	    }
223	    (void)printf(" }");
224	} else
225	    (void)printf(", %d source(s)", nsrcs);
226    }
227    (void)printf("]");
228    return;
229trunc:
230    (void)printf("[|igmp]");
231    return;
232}
233
234void
235igmp_print(register const u_char *bp, register u_int len,
236       register const u_char *bp2)
237{
238    if (qflag) {
239        (void)printf("igmp");
240        return;
241    }
242
243    TCHECK2(bp[0], 8);
244    switch (bp[0]) {
245    case 0x11:
246        (void)printf("igmp query");
247	if (len >= 12)
248	    print_igmpv3_query(bp, len, bp2);
249	else {
250	    if (bp[1]) {
251		(void)printf(" v2");
252		if (bp[1] != 100)
253		    (void)printf(" [max resp time %d]", bp[1]);
254	    } else
255		(void)printf(" v1");
256       	    if (EXTRACT_32BITS(&bp[4]))
257                (void)printf(" [gaddr %s]", ipaddr_string(&bp[4]));
258            if (len != 8)
259                (void)printf(" [len %d]", len);
260	}
261        break;
262    case 0x12:
263        (void)printf("igmp v1 report %s", ipaddr_string(&bp[4]));
264        if (len != 8)
265            (void)printf(" [len %d]", len);
266        break;
267    case 0x16:
268        (void)printf("igmp v2 report %s", ipaddr_string(&bp[4]));
269        break;
270    case 0x22:
271        (void)printf("igmp v3 report");
272	print_igmpv3_report(bp, len, bp2);
273        break;
274    case 0x17:
275        (void)printf("igmp leave %s", ipaddr_string(&bp[4]));
276        break;
277    case 0x13:
278        (void)printf("igmp dvmrp");
279        if (len < 8)
280            (void)printf(" [len %d]", len);
281        else
282            dvmrp_print(bp, len);
283        break;
284    case 0x14:
285        (void)printf("igmp pimv1");
286        pimv1_print(bp, len);
287        break;
288    case 0x1e:
289        print_mresp(bp, len);
290        break;
291    case 0x1f:
292        print_mtrace(bp, len);
293        break;
294    default:
295        (void)printf("igmp-%d", bp[0]);
296        break;
297    }
298
299    if (vflag && TTEST2(bp[0], len)) {
300        /* Check the IGMP checksum */
301        if (in_cksum((const u_short*)bp, len, 0))
302            printf(" bad igmp cksum %x!", EXTRACT_16BITS(&bp[2]));
303    }
304    return;
305trunc:
306    fputs("[|igmp]", stdout);
307}
308