packet-dvmrp.c

   1 /* packet-dvmrp.c   2001 Ronnie Sahlberg <See AUTHORS for email>
   2  * Routines for IGMP/DVMRP packet disassembly
   3  *
   4  * $Id: packet-dvmrp.c,v 1.8 2002/02/01 11:01:56 guy Exp $
   5  *
   6  * Ethereal - Network traffic analyzer
   7  * By Gerald Combs <gerald@ethereal.com>
   8  * Copyright 1998 Gerald Combs
   9  *
  10  * This program is free software; you can redistribute it and/or
  11  * modify it under the terms of the GNU General Public License
  12  * as published by the Free Software Foundation; either version 2
  13  * of the License, or (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program; if not, write to the Free Software
  22  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  23  */
  24 /*
  25
  26
  27                         DVMRP   DVMRP
  28         code            v1      v3
  29
  30         0x01            *       *
  31         0x02            *       *
  32         0x03            x
  33         0x04            x
  34         0x07                    x
  35         0x08                    x
  36         0x09                    x
  37
  38
  39         * V3 has len>=8 and byte[6]==0xff and byte[7]==0x03
  40
  41
  42         DVMRP is defined in the following RFCs
  43         RFC1075 Version 1
  44         draft-ietf-idmr-dvmrp-v3-10.txt Version 3
  45
  46         V1 and V3 can be distinguished by looking at bytes 6 and 7 in the
  47         IGMP/DVMRP header.
  48         If header[6]==0xff and header[7]==0x03 we have version 3.
  49
  50
  51         RFC1075 has typos in 3.12.2 and 3.12.4, see if you can spot them.
  52 */
  53
  54 #ifdef HAVE_CONFIG_H
  55 # include "config.h"
  56 #endif
  57
  58 #ifdef HAVE_SYS_TYPES_H
  59 # include <sys/types.h>
  60 #endif
  61
  62 #include <stdio.h>
  63 #include <string.h>
  64 #include <glib.h>
  65
  66 #include <epan/packet.h>
  67 #include "ipproto.h"
  68 #include "packet-igmp.h"
  69 #include "packet-dvmrp.h"
  70
  71 static int proto_dvmrp = -1;
  72 static int hf_version = -1;
  73 static int hf_type = -1;
  74 static int hf_code_v1 = -1;
  75 static int hf_checksum = -1;
  76 static int hf_checksum_bad = -1;
  77 static int hf_commands = -1;
  78 static int hf_command = -1;
  79 static int hf_count = -1;
  80 static int hf_afi = -1;
  81 static int hf_netmask = -1;
  82 static int hf_metric = -1;
  83 static int hf_dest_unr = -1;
  84 static int hf_split_horiz = -1;
  85 static int hf_infinity = -1;
  86 static int hf_daddr = -1;
  87 static int hf_maddr = -1;
  88 static int hf_hold = -1;
  89 static int hf_code_v3 = -1;
  90 static int hf_capabilities = -1;
  91 static int hf_cap_leaf = -1;
  92 static int hf_cap_prune = -1;
  93 static int hf_cap_genid = -1;
  94 static int hf_cap_mtrace = -1;
  95 static int hf_cap_snmp = -1;
  96 static int hf_cap_netmask = -1;
  97 static int hf_min_ver = -1;
  98 static int hf_maj_ver = -1;
  99 static int hf_genid = -1;
 100 static int hf_naddr = -1;
 101 static int hf_route = -1;
 102 static int hf_saddr = -1;
 103 static int hf_life = -1;
 104 static int hf_neighbor = -1;
 105
 106 static int ett_dvmrp = -1;
 107 static int ett_commands = -1;
 108 static int ett_capabilities = -1;
 109 static int ett_route = -1;
 110
 111
 112 #define DVMRP_TYPE                              0x13
 113 static const value_string dvmrp_type[] = {
 114         {DVMRP_TYPE,    "DVMRP" },
 115         {0,             NULL}
 116 };
 117
 118 #define DVMRP_V1_RESPONSE                       1
 119 #define DVMRP_V1_REQUEST                        2
 120 #define DVMRP_V1_NON_MEMBERSHIP_REPORT          3
 121 #define DVMRP_V1_NON_MEMBERSHIP_CANCELLATION    4
 122 static const value_string code_v1[] = {
 123         {DVMRP_V1_RESPONSE,                     "Response"                      },
 124         {DVMRP_V1_REQUEST,                      "Request"                       },
 125         {DVMRP_V1_NON_MEMBERSHIP_REPORT,        "Non-membership report"         },
 126         {DVMRP_V1_NON_MEMBERSHIP_CANCELLATION,  "Non-membership cancellation"   },
 127         {0,                                     NULL}
 128 };
 129
 130 #define DVMRP_V3_PROBE                          1
 131 #define DVMRP_V3_REPORT                         2
 132 #define DVMRP_V3_PRUNE                          7
 133 #define DVMRP_V3_GRAFT                          8
 134 #define DVMRP_V3_GRAFT_ACK                      9
 135 static const value_string code_v3[] = {
 136         {DVMRP_V3_PROBE,        "Probe"},
 137         {DVMRP_V3_REPORT,       "Report"},
 138         {DVMRP_V3_PRUNE,        "Prune"},
 139         {DVMRP_V3_GRAFT,        "Graft"},
 140         {DVMRP_V3_GRAFT_ACK,    "Graft ACK"},
 141         {0,                     NULL}
 142 };
 143
 144 #define DVMRP_V3_CAP_LEAF       0x01
 145 #define DVMRP_V3_CAP_PRUNE      0x02
 146 #define DVMRP_V3_CAP_GENID      0x04
 147 #define DVMRP_V3_CAP_MTRACE     0x08
 148 #define DVMRP_V3_CAP_SNMP       0x10
 149 #define DVMRP_V3_CAP_NETMASK    0x20
 150
 151
 152 #define V1_COMMAND_NULL         0
 153 #define V1_COMMAND_AFI          2
 154 #define V1_COMMAND_SUBNETMASK   3
 155 #define V1_COMMAND_METRIC       4
 156 #define V1_COMMAND_FLAGS0       5
 157 #define V1_COMMAND_INFINITY     6
 158 #define V1_COMMAND_DA           7
 159 #define V1_COMMAND_RDA          8
 160 #define V1_COMMAND_NMR          9
 161 #define V1_COMMAND_NMR_CANCEL   10
 162 static const value_string command[] = {
 163         {V1_COMMAND_NULL,       "NULL"  },
 164         {V1_COMMAND_AFI,        "Address Family Indicator"},
 165         {V1_COMMAND_SUBNETMASK, "Subnetmask"},
 166         {V1_COMMAND_METRIC,     "Metric"},
 167         {V1_COMMAND_FLAGS0,     "Flags0"},
 168         {V1_COMMAND_INFINITY,   "Infinity"},
 169         {V1_COMMAND_DA,         "Destination Address"},
 170         {V1_COMMAND_RDA,        "Requested Destination Address"},
 171         {V1_COMMAND_NMR,        "Non-Membership Report"},
 172         {V1_COMMAND_NMR_CANCEL, "Non-Membership Report Cancel"},
 173         {0,                     NULL}
 174 };
 175
 176 #define V1_AFI_IP               2
 177 static const value_string afi[] = {
 178         {V1_AFI_IP,     "IP v4 Family"},
 179         {0,             NULL}
 180 };
 181
 182 static const true_false_string tfs_dest_unreach = {
 183         "Destination Unreachable",
 184         "NOT Destination Unreachable"
 185 };
 186
 187 static const true_false_string tfs_split_horiz = {
 188         "Split Horizon concealed route",
 189         "NOT Split Horizon concealed route"
 190 };
 191
 192 static const true_false_string tfs_cap_leaf = {
 193         "Leaf",
 194         "NOT Leaf"
 195 };
 196 static const true_false_string tfs_cap_prune = {
 197         "Prune capable",
 198         "NOT Prune capable"
 199 };
 200 static const true_false_string tfs_cap_genid = {
 201         "Genid capable",
 202         "NOT Genid capable"
 203 };
 204 static const true_false_string tfs_cap_mtrace = {
 205         "Multicast Traceroute capable",
 206         "NOT Multicast Traceroute capable"
 207 };
 208 static const true_false_string tfs_cap_snmp = {
 209         "SNMP capable",
 210         "NOT SNMP capable"
 211 };
 212 static const true_false_string tfs_cap_netmask = {
 213         "Netmask capable",
 214         "NOT Netmask capable"
 215 };
 216
 217 int
 218 dissect_v3_report(tvbuff_t *tvb, packet_info *pinfo, proto_tree *parent_tree, int offset)
 219 {
 220         guint8 m0,m1,m2,m3;
 221         guint8 s0,s1,s2,s3;
 222         guint8 metric;
 223         guint32 ip;
 224
 225         while (tvb_reported_length_remaining(tvb, offset) > 0) {
 226                 proto_tree *tree;
 227                 proto_item *item;
 228                 int old_offset = offset;
 229
 230                 item = proto_tree_add_item(parent_tree, hf_route,
 231                                 tvb, offset, -1, FALSE);
 232                 tree = proto_item_add_subtree(item, ett_route);
 233
 234                 m0 = 0xff;
 235                 /* read the mask */
 236                 m1 = tvb_get_guint8(tvb, offset);
 237                 m2 = tvb_get_guint8(tvb, offset+1);
 238                 m3 = tvb_get_guint8(tvb, offset+2);
 239
 240                 ip = m3;
 241                 ip = (ip<<8)|m2;
 242                 ip = (ip<<8)|m1;
 243                 ip = (ip<<8)|m0;
 244                 proto_tree_add_ipv4(tree, hf_netmask, tvb, offset, 3, ip);
 245
 246                 offset += 3;
 247
 248                 /* read every srcnet, metric  pairs */
 249                 do {
 250                         int old_offset = offset;
 251                         m0 = 0xff;
 252
 253                         s0 = 0;
 254                         s1 = 0;
 255                         s2 = 0;
 256                         s3 = 0;
 257
 258                         s0 = tvb_get_guint8(tvb, offset);
 259                         offset += 1;
 260                         if (m1) {
 261                                 s1 = tvb_get_guint8(tvb, offset);
 262                                 offset += 1;
 263                         }
 264                         if (m2) {
 265                                 s2 = tvb_get_guint8(tvb, offset);
 266                                 offset += 1;
 267                         }
 268                         if (m3) {
 269                                 s3 = tvb_get_guint8(tvb, offset);
 270                                 offset += 1;
 271                         }
 272
 273                         /* handle special case for default route V3/3.4.3 */
 274                         if ((!m1)&&(!m2)&&(!m3)&&(!s0)) {
 275                                 m0 = 0;
 276                         }
 277
 278                         ip = s3;
 279                         ip = (ip<<8)|s2;
 280                         ip = (ip<<8)|s1;
 281                         ip = (ip<<8)|s0;
 282                         proto_tree_add_ipv4_format(tree, hf_saddr, tvb,
 283                                 old_offset, offset-old_offset, ip,
 284                                 "%s %d.%d.%d.%d (netmask %d.%d.%d.%d)",
 285                                 m0?"Source Network":"Default Route",
 286                                 s0,s1,s2,s3,m0,m1,m2,m3);
 287
 288                         metric = tvb_get_guint8(tvb, offset);
 289                         proto_tree_add_uint(tree, hf_metric, tvb,
 290                                 offset, 1, metric&0x7f);
 291                         offset += 1;
 292
 293
 294                 } while (!(metric&0x80));
 295
 296                 proto_item_set_len(item, offset-old_offset);
 297         }
 298
 299         return offset;
 300 }
 301
 302 int
 303 dissect_dvmrp_v3(tvbuff_t *tvb, packet_info *pinfo, proto_tree *parent_tree, int offset)
 304 {
 305         guint8 code,count;
 306
 307         /* version */
 308         proto_tree_add_uint(parent_tree, hf_version, tvb, 0, 0, 3);
 309
 310         /* type of command */
 311         proto_tree_add_uint(parent_tree, hf_type, tvb, offset, 1, 0x13);
 312         offset += 1;
 313
 314         /* code */
 315         code = tvb_get_guint8(tvb, offset);
 316         proto_tree_add_uint(parent_tree, hf_code_v3, tvb, offset, 1, code);
 317         offset += 1;
 318         if (check_col(pinfo->cinfo, COL_INFO)) {
 319                 col_add_fstr(pinfo->cinfo, COL_INFO,
 320                         "V%d %s",3 ,val_to_str(code, code_v3,
 321                                 "Unknown Type:0x%02x"));
 322         }
 323
 324         /* checksum */
 325         igmp_checksum(parent_tree, tvb, hf_checksum, hf_checksum_bad, pinfo, 0);
 326         offset += 2;
 327
 328         /* skip unused byte */
 329         offset += 1;
 330
 331         /* PROBE packets have capabilities flags, unused for other packets */
 332         if (code==DVMRP_V3_PROBE) {
 333                 proto_tree *tree;
 334                 proto_item *item;
 335
 336                 item = proto_tree_add_item(parent_tree, hf_capabilities,
 337                                 tvb, offset, 1, FALSE);
 338                 tree = proto_item_add_subtree(item, ett_capabilities);
 339
 340                 count = tvb_get_guint8(tvb, offset);
 341                 proto_tree_add_boolean(tree, hf_cap_netmask, tvb, offset, 1, count);
 342                 proto_tree_add_boolean(tree, hf_cap_snmp, tvb, offset, 1, count);
 343                 proto_tree_add_boolean(tree, hf_cap_mtrace, tvb, offset, 1, count);
 344                 proto_tree_add_boolean(tree, hf_cap_genid, tvb, offset, 1, count);
 345                 proto_tree_add_boolean(tree, hf_cap_prune, tvb, offset, 1, count);
 346                 proto_tree_add_boolean(tree, hf_cap_leaf, tvb, offset, 1, count);
 347         }
 348         offset += 1;
 349
 350         /* minor version */
 351         proto_tree_add_item(parent_tree, hf_min_ver, tvb, offset, 1, FALSE);
 352         offset += 1;
 353
 354         /* major version */
 355         proto_tree_add_item(parent_tree, hf_maj_ver, tvb, offset, 1, FALSE);
 356         offset += 1;
 357
 358         switch (code) {
 359         case DVMRP_V3_PROBE:
 360                 /* generation id */
 361                 proto_tree_add_item(parent_tree, hf_genid, tvb,
 362                         offset, 4, FALSE);
 363                 offset += 4;
 364                 while (tvb_reported_length_remaining(tvb, offset) > 0) {
 365                         proto_tree_add_item(parent_tree, hf_neighbor,
 366                                 tvb, offset, 4, FALSE);
 367                         offset += 4;
 368                 }
 369                 break;
 370         case DVMRP_V3_REPORT:
 371                 offset = dissect_v3_report(tvb, pinfo, parent_tree, offset);
 372                 break;
 373         case DVMRP_V3_PRUNE:
 374                 /* source address */
 375                 proto_tree_add_item(parent_tree, hf_saddr,
 376                         tvb, offset, 4, FALSE);
 377                 offset += 4;
 378                 /* group address */
 379                 proto_tree_add_item(parent_tree, hf_maddr,
 380                         tvb, offset, 4, FALSE);
 381                 offset += 4;
 382                 /* prune lifetime */
 383                 proto_tree_add_item(parent_tree, hf_life,
 384                         tvb, offset, 4, FALSE);
 385                 offset += 4;
 386                 /* source netmask */
 387                 if (tvb_reported_length_remaining(tvb, offset)>=4) {
 388                         proto_tree_add_item(parent_tree, hf_netmask,
 389                                 tvb, offset, 4, FALSE);
 390                         offset += 4;
 391                 }
 392                 break;
 393         case DVMRP_V3_GRAFT:
 394                 /* source address */
 395                 proto_tree_add_item(parent_tree, hf_saddr,
 396                         tvb, offset, 4, FALSE);
 397                 offset += 4;
 398                 /* group address */
 399                 proto_tree_add_item(parent_tree, hf_maddr,
 400                         tvb, offset, 4, FALSE);
 401                 offset += 4;
 402                 /* source netmask */
 403                 if (tvb_reported_length_remaining(tvb, offset)>=4) {
 404                         proto_tree_add_item(parent_tree, hf_netmask,
 405                                 tvb, offset, 4, FALSE);
 406                         offset += 4;
 407                 }
 408                 break;
 409         case DVMRP_V3_GRAFT_ACK:
 410                 /* source address */
 411                 proto_tree_add_item(parent_tree, hf_saddr,
 412                         tvb, offset, 4, FALSE);
 413                 offset += 4;
 414                 /* group address */
 415                 proto_tree_add_item(parent_tree, hf_maddr,
 416                         tvb, offset, 4, FALSE);
 417                 offset += 4;
 418                 /* source netmask */
 419                 if (tvb_reported_length_remaining(tvb, offset)>=4) {
 420                         proto_tree_add_item(parent_tree, hf_netmask,
 421                                 tvb, offset, 4, FALSE);
 422                         offset += 4;
 423                 }
 424                 break;
 425         }
 426
 427         return offset;
 428 }
 429
 430
 431 int
 432 dissect_dvmrp_v1(tvbuff_t *tvb, packet_info *pinfo, proto_tree *parent_tree, int offset)
 433 {
 434         guint8 code;
 435         guint8 af=2; /* default */
 436
 437         /* version */
 438         proto_tree_add_uint(parent_tree, hf_version, tvb, 0, 0, 1);
 439
 440         /* type of command */
 441         proto_tree_add_uint(parent_tree, hf_type, tvb, offset, 1, 0x13);
 442         offset += 1;
 443
 444         /* code */
 445         code = tvb_get_guint8(tvb, offset);
 446         proto_tree_add_uint(parent_tree, hf_code_v1, tvb, offset, 1, code);
 447         offset += 1;
 448         if (check_col(pinfo->cinfo, COL_INFO)) {
 449                 col_add_fstr(pinfo->cinfo, COL_INFO,
 450                         "V%d %s",1 ,val_to_str(code, code_v1,
 451                                 "Unknown Type:0x%02x"));
 452         }
 453
 454         /* checksum */
 455         igmp_checksum(parent_tree, tvb, hf_checksum, hf_checksum_bad, pinfo, 0);
 456         offset += 2;
 457
 458         /* decode all the v1 commands */
 459         while (tvb_reported_length_remaining(tvb, offset)) {
 460                 proto_tree *tree;
 461                 proto_item *item;
 462                 guint8 cmd,count;
 463                 int old_offset = offset;
 464
 465                 item = proto_tree_add_item(parent_tree, hf_commands,
 466                                 tvb, offset, -1, FALSE);
 467                 tree = proto_item_add_subtree(item, ett_commands);
 468
 469                 cmd = tvb_get_guint8(tvb, offset);
 470                 proto_tree_add_uint(tree, hf_command, tvb,
 471                         offset, 1, cmd);
 472                 offset += 1;
 473
 474                 switch (cmd){
 475                 case V1_COMMAND_NULL:
 476                         offset += 1; /* skip ignored/pad byte*/
 477                         if (item) {
 478                                 proto_item_set_text(item, "Command: NULL");
 479                         }
 480                         break;
 481                 case V1_COMMAND_AFI:
 482                         af = tvb_get_guint8(tvb, offset);
 483                         proto_tree_add_uint(tree, hf_afi, tvb,
 484                                 offset, 1, af);
 485                         offset += 1;
 486                         if (item) {
 487                                 proto_item_set_text(item, "%s: %s",
 488                                         val_to_str(cmd, command, "Unknown Command:0x%02x"),
 489                                         val_to_str(af, afi, "Unknown Family:0x%02x")
 490                                 );
 491                         }
 492                         break;
 493                 case V1_COMMAND_SUBNETMASK:
 494                         count = tvb_get_guint8(tvb, offset);
 495                         proto_tree_add_uint(tree, hf_count, tvb,
 496                                 offset, 1, count);
 497                         offset += 1;
 498                         if (count) { /* must be 0 or 1 */
 499                                 proto_tree_add_item(tree, hf_netmask,
 500                                         tvb, offset, 4, FALSE);
 501                                 if (item) {
 502                                         proto_item_set_text(item, "%s: %d.%d.%d.%d",
 503                                                 val_to_str(cmd, command, "Unknown Command:0x%02x"),
 504                                                 tvb_get_guint8(tvb, offset),
 505                                                 tvb_get_guint8(tvb, offset+1),
 506                                                 tvb_get_guint8(tvb, offset+2),
 507                                                 tvb_get_guint8(tvb, offset+3));
 508                                 }
 509                                 offset += 4;
 510                         } else {
 511                                 if (item) {
 512                                         proto_item_set_text(item, "%s: <no mask supplied>",
 513                                                 val_to_str(cmd, command, "Unknown Command:0x%02x"));
 514                                 }
 515                         }
 516                         break;
 517                 case V1_COMMAND_METRIC:
 518                         proto_tree_add_item(tree, hf_metric, tvb,
 519                                 offset, 1, FALSE);
 520                         if (item) {
 521                                 proto_item_set_text(item, "%s: %d",
 522                                         val_to_str(cmd, command, "Unknown Command:0x%02x"),
 523                                         tvb_get_guint8(tvb, offset));
 524                         }
 525                         offset += 1;
 526                         break;
 527                 case V1_COMMAND_FLAGS0:
 528                         count = tvb_get_guint8(tvb, offset);
 529                         proto_tree_add_boolean(tree, hf_dest_unr, tvb, offset, 1, count);
 530                         proto_tree_add_boolean(tree, hf_split_horiz, tvb, offset, 1, count);
 531                         if (item) {
 532                                 proto_item_set_text(item, "%s: 0x%02x",
 533                                         val_to_str(cmd, command, "Unknown Command:0x%02x"), count);
 534                         }
 535                         offset += 1;
 536                         break;
 537                 case V1_COMMAND_INFINITY:
 538                         proto_tree_add_item(tree, hf_infinity, tvb,
 539                                 offset, 1, FALSE);
 540                         if (item) {
 541                                 proto_item_set_text(item, "%s: %d",
 542                                         val_to_str(cmd, command, "Unknown Command:0x%02x"), tvb_get_guint8(tvb, offset));
 543                         }
 544                         offset += 1;
 545                         break;
 546                 case V1_COMMAND_DA:
 547                 case V1_COMMAND_RDA: /* same as DA */
 548                         count = tvb_get_guint8(tvb, offset);
 549                         proto_tree_add_uint(tree, hf_count, tvb,
 550                                 offset, 1, count);
 551                         offset += 1;
 552                         while (count--) {
 553                                 proto_tree_add_item(tree, hf_daddr,
 554                                         tvb, offset, 4, FALSE);
 555                                 offset += 4;
 556                         }
 557                         if (item) {
 558                                 proto_item_set_text(item, "%s",
 559                                         val_to_str(cmd, command, "Unknown Command:0x%02x"));
 560                         }
 561                         break;
 562                 case V1_COMMAND_NMR:
 563                         count = tvb_get_guint8(tvb, offset);
 564                         proto_tree_add_uint(tree, hf_count, tvb,
 565                                 offset, 1, count);
 566                         offset += 1;
 567                         while (count--) {
 568                                 proto_tree_add_item(tree, hf_maddr,
 569                                         tvb, offset, 4, FALSE);
 570                                 offset += 4;
 571                                 proto_tree_add_item(tree, hf_hold, tvb,
 572                                         offset, 4, FALSE);
 573                                 offset += 4;
 574                         }
 575                         if (item) {
 576                                 proto_item_set_text(item, "%s",
 577                                         val_to_str(cmd, command, "Unknown Command:0x%02x"));
 578                         }
 579                         break;
 580                 case V1_COMMAND_NMR_CANCEL:
 581                         count = tvb_get_guint8(tvb, offset);
 582                         proto_tree_add_uint(tree, hf_count, tvb,
 583                                 offset, 1, count);
 584                         offset += 1;
 585                         while (count--) {
 586                                 proto_tree_add_item(tree, hf_maddr,
 587                                         tvb, offset, 4, FALSE);
 588                                 offset += 4;
 589                         }
 590                         if (item) {
 591                                 proto_item_set_text(item, "%s",
 592                                         val_to_str(cmd, command, "Unknown Command:0x%02x"));
 593                         }
 594                         break;
 595                 }
 596
 597                 proto_item_set_len(item, offset-old_offset);
 598         }
 599
 600         return offset;
 601 }
 602
 603 /* This function is only called from the IGMP dissector */
 604 int
 605 dissect_dvmrp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *parent_tree, int offset)
 606 {
 607         proto_tree *tree;
 608         proto_item *item;
 609
 610         if (!proto_is_protocol_enabled(proto_dvmrp)) {
 611                 /* we are not enabled, skip entire packet to be nice
 612                    to the igmp layer. (so clicking on IGMP will display the data)
 613                  */
 614                 return offset+tvb_length_remaining(tvb, offset);
 615         }
 616
 617         item = proto_tree_add_item(parent_tree, proto_dvmrp, tvb, offset, -1, FALSE);
 618         tree = proto_item_add_subtree(item, ett_dvmrp);
 619
 620
 621         if (check_col(pinfo->cinfo, COL_PROTOCOL)) {
 622                 col_set_str(pinfo->cinfo, COL_PROTOCOL, "DVMRP");
 623         }
 624         if (check_col(pinfo->cinfo, COL_INFO)) {
 625                 col_clear(pinfo->cinfo, COL_INFO);
 626         }
 627
 628
 629         if ((tvb_length_remaining(tvb, offset)>=8)
 630          && (tvb_get_guint8(tvb, 6)==0xff)
 631          && (tvb_get_guint8(tvb, 7)==0x03)) {
 632                 offset = dissect_dvmrp_v3(tvb, pinfo, tree, offset);
 633                 proto_item_set_len(item, offset);
 634                 return offset;
 635         }
 636
 637
 638         offset = dissect_dvmrp_v1(tvb, pinfo, tree, offset);
 639         proto_item_set_len(item, offset);
 640         return offset;
 641 }
 642
 643 void
 644 proto_register_dvmrp(void)
 645 {
 646         static hf_register_info hf[] = {
 647                 { &hf_version,
 648                         { "DVMRP Version", "dvmrp.version", FT_UINT8, BASE_DEC,
 649                           NULL, 0, "DVMRP Version", HFILL }},
 650
 651                 { &hf_type,
 652                         { "Type", "dvmrp.type", FT_UINT8, BASE_HEX,
 653                           VALS(dvmrp_type), 0, "DVMRP Packet Type", HFILL }},
 654
 655                 { &hf_code_v1,
 656                         { "Code", "dvmrp.v1.code", FT_UINT8, BASE_HEX,
 657                           VALS(code_v1), 0, "DVMRP Packet Code", HFILL }},
 658
 659                 { &hf_checksum,
 660                         { "Checksum", "dvmrp.checksum", FT_UINT16, BASE_HEX,
 661                           NULL, 0, "DVMRP Checksum", HFILL }},
 662
 663                 { &hf_checksum_bad,
 664                         { "Bad Checksum", "dvmrp.checksum_bad", FT_BOOLEAN, BASE_NONE,
 665                           NULL, 0, "Bad DVMRP Checksum", HFILL }},
 666
 667                 { &hf_commands,
 668                         { "Commands", "dvmrp.commands", FT_NONE, BASE_NONE,
 669                           NULL, 0, "DVMRP V1 Commands", HFILL }},
 670
 671                 { &hf_command,
 672                         { "Command", "dvmrp.command", FT_UINT8, BASE_HEX,
 673                           VALS(command), 0, "DVMRP V1 Command", HFILL }},
 674
 675                 { &hf_afi,
 676                         { "Address Family", "dvmrp.afi", FT_UINT8, BASE_HEX,
 677                           VALS(afi), 0, "DVMRP Address Family Indicator", HFILL }},
 678
 679                 { &hf_count,
 680                         { "Count", "dvmrp.count", FT_UINT8, BASE_HEX,
 681                           NULL, 0, "Count", HFILL }},
 682
 683                 { &hf_netmask,
 684                         { "Netmask", "igmp.netmask", FT_IPv4, BASE_NONE,
 685                           NULL, 0, "DVMRP Netmask", HFILL }},
 686
 687                 { &hf_metric,
 688                         { "Metric", "dvmrp.metric", FT_UINT8, BASE_DEC,
 689                           NULL, 0, "DVMRP Metric", HFILL }},
 690
 691                 {&hf_dest_unr,
 692                         { "Destination Unreachable", "dvmrp.dest_unreach", FT_BOOLEAN, 8,
 693                         TFS(&tfs_dest_unreach), 0x01, "Destination Unreachable", HFILL }},
 694
 695                 {&hf_split_horiz,
 696                         { "Split Horizon", "dvmrp.split_horiz", FT_BOOLEAN, 8,
 697                         TFS(&tfs_split_horiz), 0x02, "Split Horizon concealed route", HFILL }},
 698
 699                 { &hf_infinity,
 700                         { "Infinity", "dvmrp.infinity", FT_UINT8, BASE_DEC,
 701                           NULL, 0, "DVMRP Infinity", HFILL }},
 702
 703                 { &hf_daddr,
 704                         { "Dest Addr", "igmp.daddr", FT_IPv4, BASE_NONE,
 705                           NULL, 0, "DVMRP Destination Address", HFILL }},
 706
 707                 { &hf_maddr,
 708                         { "Multicast Addr", "igmp.maddr", FT_IPv4, BASE_NONE,
 709                           NULL, 0, "DVMRP Multicast Address", HFILL }},
 710
 711                 { &hf_hold,
 712                         { "Hold Time", "dvmrp.hold", FT_UINT32, BASE_DEC,
 713                           NULL, 0, "DVMRP Hold Time in seconds", HFILL }},
 714
 715                 { &hf_code_v3,
 716                         { "Code", "dvmrp.v3.code", FT_UINT8, BASE_HEX,
 717                           VALS(code_v3), 0, "DVMRP Packet Code", HFILL }},
 718
 719                 { &hf_capabilities,
 720                         { "Capabilities", "dvmrp.capabilities", FT_NONE, BASE_NONE,
 721                           NULL, 0, "DVMRP V3 Capabilities", HFILL }},
 722
 723                 {&hf_cap_leaf,
 724                         { "Leaf", "dvmrp.cap.leaf", FT_BOOLEAN, 8,
 725                         TFS(&tfs_cap_leaf), DVMRP_V3_CAP_LEAF, "Leaf", HFILL }},
 726
 727                 {&hf_cap_prune,
 728                         { "Prune", "dvmrp.cap.prune", FT_BOOLEAN, 8,
 729                         TFS(&tfs_cap_prune), DVMRP_V3_CAP_PRUNE, "Prune capability", HFILL }},
 730
 731                 {&hf_cap_genid,
 732                         { "Genid", "dvmrp.cap.genid", FT_BOOLEAN, 8,
 733                         TFS(&tfs_cap_genid), DVMRP_V3_CAP_GENID, "Genid capability", HFILL }},
 734
 735                 {&hf_cap_mtrace,
 736                         { "Mtrace", "dvmrp.cap.mtrace", FT_BOOLEAN, 8,
 737                         TFS(&tfs_cap_mtrace), DVMRP_V3_CAP_MTRACE, "Mtrace capability", HFILL }},
 738
 739                 {&hf_cap_snmp,
 740                         { "SNMP", "dvmrp.cap.snmp", FT_BOOLEAN, 8,
 741                         TFS(&tfs_cap_snmp), DVMRP_V3_CAP_SNMP, "SNMP capability", HFILL }},
 742
 743                 {&hf_cap_netmask,
 744                         { "Netmask", "dvmrp.cap.netmask", FT_BOOLEAN, 8,
 745                         TFS(&tfs_cap_netmask), DVMRP_V3_CAP_NETMASK, "Netmask capability", HFILL }},
 746
 747                 { &hf_min_ver,
 748                         { "Minor Version", "dvmrp.min_ver", FT_UINT8, BASE_HEX,
 749                           NULL, 0, "DVMRP Minor Version", HFILL }},
 750
 751                 { &hf_maj_ver,
 752                         { "Major Version", "dvmrp.maj_ver", FT_UINT8, BASE_HEX,
 753                           NULL, 0, "DVMRP Major Version", HFILL }},
 754
 755                 { &hf_genid,
 756                         { "Generation ID", "dvmrp.genid", FT_UINT32, BASE_DEC,
 757                           NULL, 0, "DVMRP Generation ID", HFILL }},
 758
 759                 { &hf_naddr,
 760                         { "Neighbor Addr", "igmp.naddr", FT_IPv4, BASE_NONE,
 761                           NULL, 0, "DVMRP Neighbor Address", HFILL }},
 762
 763                 { &hf_route,
 764                         { "Route", "dvmrp.route", FT_NONE, BASE_NONE,
 765                           NULL, 0, "DVMRP V3 Route Report", HFILL }},
 766
 767                 { &hf_saddr,
 768                         { "Source Addr", "igmp.saddr", FT_IPv4, BASE_NONE,
 769                           NULL, 0, "DVMRP Source Address", HFILL }},
 770
 771                 { &hf_life,
 772                         { "Prune lifetime", "dvmrp.lifetime", FT_UINT32, BASE_DEC,
 773                           NULL, 0, "DVMRP Prune Lifetime", HFILL }},
 774
 775                 { &hf_neighbor,
 776                         { "Neighbor Addr", "igmp.neighbor", FT_IPv4, BASE_NONE,
 777                           NULL, 0, "DVMRP Neighbor Address", HFILL }},
 778
 779         };
 780         static gint *ett[] = {
 781                 &ett_dvmrp,
 782                 &ett_commands,
 783                 &ett_capabilities,
 784                 &ett_route,
 785         };
 786
 787         proto_dvmrp = proto_register_protocol("Distance Vector Multicast Routing Protocol",
 788             "DVMRP", "dvmrp");
 789         proto_register_field_array(proto_dvmrp, hf, array_length(hf));
 790         proto_register_subtree_array(ett, array_length(ett));
 791 }