The Tcpdump Group git mirrors - tcpdump/blob - print-igmp.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 #define NETDISSECT_REWORKED
  23 #ifdef HAVE_CONFIG_H
  24 #include "config.h"
  25 #endif
  26
  27 #include <tcpdump-stdinc.h>
  28
  29 #include "interface.h"
  30 #include "addrtoname.h"
  31 #include "extract.h"            /* must come after interface.h */
  32
  33 #ifndef IN_CLASSD
  34 #define IN_CLASSD(i) (((int32_t)(i) & 0xf0000000) == 0xe0000000)
  35 #endif
  36
  37 static const char tstr[] = "[|igmp]";
  38
  39 /* (following from ipmulti/mrouted/prune.h) */
  40
  41 /*
  42  * The packet format for a traceroute request.
  43  */
  44 struct tr_query {
  45     u_int32_t  tr_src;          /* traceroute source */
  46     u_int32_t  tr_dst;          /* traceroute destination */
  47     u_int32_t  tr_raddr;        /* traceroute response address */
  48     u_int32_t  tr_rttlqid;      /* response ttl and qid */
  49 };
  50
  51 #define TR_GETTTL(x)        (int)(((x) >> 24) & 0xff)
  52 #define TR_GETQID(x)        ((x) & 0x00ffffff)
  53
  54 /*
  55  * Traceroute response format.  A traceroute response has a tr_query at the
  56  * beginning, followed by one tr_resp for each hop taken.
  57  */
  58 struct tr_resp {
  59     u_int32_t tr_qarr;          /* query arrival time */
  60     u_int32_t tr_inaddr;        /* incoming interface address */
  61     u_int32_t tr_outaddr;       /* outgoing interface address */
  62     u_int32_t tr_rmtaddr;       /* parent address in source tree */
  63     u_int32_t tr_vifin;         /* input packet count on interface */
  64     u_int32_t tr_vifout;        /* output packet count on interface */
  65     u_int32_t tr_pktcnt;        /* total incoming packets for src-grp */
  66     u_int8_t  tr_rproto;      /* routing proto deployed on router */
  67     u_int8_t  tr_fttl;        /* ttl required to forward on outvif */
  68     u_int8_t  tr_smask;       /* subnet mask for src addr */
  69     u_int8_t  tr_rflags;      /* forwarding error codes */
  70 };
  71
  72 /* defs within mtrace */
  73 #define TR_QUERY 1
  74 #define TR_RESP 2
  75
  76 /* fields for tr_rflags (forwarding error codes) */
  77 #define TR_NO_ERR   0
  78 #define TR_WRONG_IF 1
  79 #define TR_PRUNED   2
  80 #define TR_OPRUNED  3
  81 #define TR_SCOPED   4
  82 #define TR_NO_RTE   5
  83 #define TR_NO_FWD   7
  84 #define TR_NO_SPACE 0x81
  85 #define TR_OLD_ROUTER   0x82
  86
  87 /* fields for tr_rproto (routing protocol) */
  88 #define TR_PROTO_DVMRP  1
  89 #define TR_PROTO_MOSPF  2
  90 #define TR_PROTO_PIM    3
  91 #define TR_PROTO_CBT    4
  92
  93 /* igmpv3 report types */
  94 static const struct tok igmpv3report2str[] = {
  95         { 1,    "is_in" },
  96         { 2,    "is_ex" },
  97         { 3,    "to_in" },
  98         { 4,    "to_ex" },
  99         { 5,    "allow" },
 100         { 6,    "block" },
 101         { 0,    NULL }
 102 };
 103
 104 static void
 105 print_mtrace(netdissect_options *ndo,
 106              register const u_char *bp, register u_int len)
 107 {
 108     register const struct tr_query *tr = (const struct tr_query *)(bp + 8);
 109
 110     ND_TCHECK(*tr);
 111     if (len < 8 + sizeof (struct tr_query)) {
 112         ND_PRINT((ndo, " [invalid len %d]", len));
 113         return;
 114     }
 115     ND_PRINT((ndo, "mtrace %u: %s to %s reply-to %s",
 116         TR_GETQID(EXTRACT_32BITS(&tr->tr_rttlqid)),
 117         ipaddr_string(ndo, &tr->tr_src), ipaddr_string(ndo, &tr->tr_dst),
 118         ipaddr_string(ndo, &tr->tr_raddr)));
 119     if (IN_CLASSD(EXTRACT_32BITS(&tr->tr_raddr)))
 120         ND_PRINT((ndo, " with-ttl %d", TR_GETTTL(EXTRACT_32BITS(&tr->tr_rttlqid))));
 121     return;
 122 trunc:
 123     ND_PRINT((ndo, "%s", tstr));
 124 }
 125
 126 static void
 127 print_mresp(netdissect_options *ndo,
 128             register const u_char *bp, register u_int len)
 129 {
 130     register const struct tr_query *tr = (const struct tr_query *)(bp + 8);
 131
 132     ND_TCHECK(*tr);
 133     if (len < 8 + sizeof (struct tr_query)) {
 134         ND_PRINT((ndo, " [invalid len %d]", len));
 135         return;
 136     }
 137     ND_PRINT((ndo, "mresp %lu: %s to %s reply-to %s",
 138         (u_long)TR_GETQID(EXTRACT_32BITS(&tr->tr_rttlqid)),
 139         ipaddr_string(ndo, &tr->tr_src), ipaddr_string(ndo, &tr->tr_dst),
 140         ipaddr_string(ndo, &tr->tr_raddr)));
 141     if (IN_CLASSD(EXTRACT_32BITS(&tr->tr_raddr)))
 142         ND_PRINT((ndo, " with-ttl %d", TR_GETTTL(EXTRACT_32BITS(&tr->tr_rttlqid))));
 143     return;
 144 trunc:
 145     ND_PRINT((ndo, "%s", tstr));
 146 }
 147
 148 static void
 149 print_igmpv3_report(netdissect_options *ndo,
 150                     register const u_char *bp, register u_int len)
 151 {
 152     u_int group, nsrcs, ngroups;
 153     register u_int i, j;
 154
 155     /* Minimum len is 16, and should be a multiple of 4 */
 156     if (len < 16 || len & 0x03) {
 157         ND_PRINT((ndo, " [invalid len %d]", len));
 158         return;
 159     }
 160     ND_TCHECK2(bp[6], 2);
 161     ngroups = EXTRACT_16BITS(&bp[6]);
 162     ND_PRINT((ndo, ", %d group record(s)", ngroups));
 163     if (ndo->ndo_vflag > 0) {
 164         /* Print the group records */
 165         group = 8;
 166         for (i=0; i<ngroups; i++) {
 167             if (len < group+8) {
 168                 ND_PRINT((ndo, " [invalid number of groups]"));
 169                 return;
 170             }
 171             ND_TCHECK2(bp[group+4], 4);
 172             ND_PRINT((ndo, " [gaddr %s", ipaddr_string(ndo, &bp[group+4])));
 173             ND_PRINT((ndo, " %s", tok2str(igmpv3report2str, " [v3-report-#%d]",
 174                                                                 bp[group])));
 175             nsrcs = EXTRACT_16BITS(&bp[group+2]);
 176             /* Check the number of sources and print them */
 177             if (len < group+8+(nsrcs<<2)) {
 178                 ND_PRINT((ndo, " [invalid number of sources %d]", nsrcs));
 179                 return;
 180             }
 181             if (ndo->ndo_vflag == 1)
 182                 ND_PRINT((ndo, ", %d source(s)", nsrcs));
 183             else {
 184                 /* Print the sources */
 185                 ND_PRINT((ndo, " {"));
 186                 for (j=0; j<nsrcs; j++) {
 187                     ND_TCHECK2(bp[group+8+(j<<2)], 4);
 188                     ND_PRINT((ndo, " %s", ipaddr_string(ndo, &bp[group+8+(j<<2)])));
 189                 }
 190                 ND_PRINT((ndo, " }"));
 191             }
 192             /* Next group record */
 193             group += 8 + (nsrcs << 2);
 194             ND_PRINT((ndo, "]"));
 195         }
 196     }
 197     return;
 198 trunc:
 199     ND_PRINT((ndo, "%s", tstr));
 200 }
 201
 202 static void
 203 print_igmpv3_query(netdissect_options *ndo,
 204                    register const u_char *bp, register u_int len)
 205 {
 206     u_int mrc;
 207     int mrt;
 208     u_int nsrcs;
 209     register u_int i;
 210
 211     ND_PRINT((ndo, " v3"));
 212     /* Minimum len is 12, and should be a multiple of 4 */
 213     if (len < 12 || len & 0x03) {
 214         ND_PRINT((ndo, " [invalid len %d]", len));
 215         return;
 216     }
 217     ND_TCHECK(bp[1]);
 218     mrc = bp[1];
 219     if (mrc < 128) {
 220         mrt = mrc;
 221     } else {
 222         mrt = ((mrc & 0x0f) | 0x10) << (((mrc & 0x70) >> 4) + 3);
 223     }
 224     if (mrc != 100) {
 225         ND_PRINT((ndo, " [max resp time "));
 226         if (mrt < 600) {
 227             ND_PRINT((ndo, "%.1fs", mrt * 0.1));
 228         } else {
 229             relts_print(ndo, mrt / 10);
 230         }
 231         ND_PRINT((ndo, "]"));
 232     }
 233     ND_TCHECK2(bp[4], 4);
 234     if (EXTRACT_32BITS(&bp[4]) == 0)
 235         return;
 236     ND_PRINT((ndo, " [gaddr %s", ipaddr_string(ndo, &bp[4])));
 237     ND_TCHECK2(bp[10], 2);
 238     nsrcs = EXTRACT_16BITS(&bp[10]);
 239     if (nsrcs > 0) {
 240         if (len < 12 + (nsrcs << 2))
 241             ND_PRINT((ndo, " [invalid number of sources]"));
 242         else if (ndo->ndo_vflag > 1) {
 243             ND_PRINT((ndo, " {"));
 244             for (i=0; i<nsrcs; i++) {
 245                 ND_TCHECK2(bp[12+(i<<2)], 4);
 246                 ND_PRINT((ndo, " %s", ipaddr_string(ndo, &bp[12+(i<<2)])));
 247             }
 248             ND_PRINT((ndo, " }"));
 249         } else
 250             ND_PRINT((ndo, ", %d source(s)", nsrcs));
 251     }
 252     ND_PRINT((ndo, "]"));
 253     return;
 254 trunc:
 255     ND_PRINT((ndo, "%s", tstr));
 256 }
 257
 258 void
 259 igmp_print(netdissect_options *ndo,
 260            register const u_char *bp, register u_int len)
 261 {
 262     struct cksum_vec vec[1];
 263
 264     if (ndo->ndo_qflag) {
 265         ND_PRINT((ndo, "igmp"));
 266         return;
 267     }
 268
 269     ND_TCHECK(bp[0]);
 270     switch (bp[0]) {
 271     case 0x11:
 272         ND_PRINT((ndo, "igmp query"));
 273         if (len >= 12)
 274             print_igmpv3_query(ndo, bp, len);
 275         else {
 276             ND_TCHECK(bp[1]);
 277             if (bp[1]) {
 278                 ND_PRINT((ndo, " v2"));
 279                 if (bp[1] != 100)
 280                     ND_PRINT((ndo, " [max resp time %d]", bp[1]));
 281             } else
 282                 ND_PRINT((ndo, " v1"));
 283             ND_TCHECK2(bp[4], 4);
 284             if (EXTRACT_32BITS(&bp[4]))
 285                 ND_PRINT((ndo, " [gaddr %s]", ipaddr_string(ndo, &bp[4])));
 286             if (len != 8)
 287                 ND_PRINT((ndo, " [len %d]", len));
 288         }
 289         break;
 290     case 0x12:
 291         ND_TCHECK2(bp[4], 4);
 292         ND_PRINT((ndo, "igmp v1 report %s", ipaddr_string(ndo, &bp[4])));
 293         if (len != 8)
 294             ND_PRINT((ndo, " [len %d]", len));
 295         break;
 296     case 0x16:
 297         ND_TCHECK2(bp[4], 4);
 298         ND_PRINT((ndo, "igmp v2 report %s", ipaddr_string(ndo, &bp[4])));
 299         break;
 300     case 0x22:
 301         ND_PRINT((ndo, "igmp v3 report"));
 302         print_igmpv3_report(ndo, bp, len);
 303         break;
 304     case 0x17:
 305         ND_TCHECK2(bp[4], 4);
 306         ND_PRINT((ndo, "igmp leave %s", ipaddr_string(ndo, &bp[4])));
 307         break;
 308     case 0x13:
 309         ND_PRINT((ndo, "igmp dvmrp"));
 310         if (len < 8)
 311             ND_PRINT((ndo, " [len %d]", len));
 312         else
 313             dvmrp_print(ndo, bp, len);
 314         break;
 315     case 0x14:
 316         ND_PRINT((ndo, "igmp pimv1"));
 317         pimv1_print(ndo, bp, len);
 318         break;
 319     case 0x1e:
 320         print_mresp(ndo, bp, len);
 321         break;
 322     case 0x1f:
 323         print_mtrace(ndo, bp, len);
 324         break;
 325     default:
 326         ND_PRINT((ndo, "igmp-%d", bp[0]));
 327         break;
 328     }
 329
 330     if (ndo->ndo_vflag && ND_TTEST2(bp[0], len)) {
 331         /* Check the IGMP checksum */
 332         vec[0].ptr = bp;
 333         vec[0].len = len;
 334         if (in_cksum(vec, 1))
 335             ND_PRINT((ndo, " bad igmp cksum %x!", EXTRACT_16BITS(&bp[2])));
 336     }
 337     return;
 338 trunc:
 339     ND_PRINT((ndo, "%s", tstr));
 340 }