packet-dvmrp.c

   1 /* packet-dvmrp.c   2001 Ronnie Sahlberg <rsahlber@bigpond.net.au>
   2  * Routines for IGMP/DVMRP packet disassembly
   3  *
   4  * $Id: packet-dvmrp.c,v 1.2 2001/06/18 02:17:46 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 "packet.h"
  67 #include "ipproto.h"
  68 #include "in_cksum.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 static void dvmrp_checksum(proto_tree *tree,tvbuff_t *tvb, int len)
 218 {
 219         guint16 cksum,hdrcksum;
 220         vec_t cksum_vec[1];
 221
 222         cksum_vec[0].ptr = tvb_get_ptr(tvb, 0, len);
 223         cksum_vec[0].len = len;
 224
 225         hdrcksum = tvb_get_ntohs(tvb, 2);
 226         cksum = in_cksum(&cksum_vec[0],1);
 227
 228         if (cksum==0) {
 229                 proto_tree_add_uint_format(tree, hf_checksum, tvb, 2, 2, hdrcksum, "Header checksum: 0x%04x (correct)", hdrcksum);
 230         } else {
 231                 proto_tree_add_item_hidden(tree, hf_checksum_bad, tvb, 2, 2, TRUE);
 232                 proto_tree_add_uint_format(tree, hf_checksum, tvb, 2, 2, hdrcksum, "Header checksum: 0x%04x (incorrect, should be 0x%04x)", hdrcksum,in_cksum_shouldbe(hdrcksum,cksum));
 233         }
 234
 235         return;
 236 }
 237
 238
 239
 240 int
 241 dissect_v3_report(tvbuff_t *tvb, packet_info *pinfo, proto_tree *parent_tree, int offset)
 242 {
 243         guint8 m0,m1,m2,m3;
 244         guint8 s0,s1,s2,s3;
 245         guint8 metric;
 246         guint32 ip;
 247
 248         while (tvb_length_remaining(tvb, offset)) {
 249                 proto_tree *tree;
 250                 proto_item *item;
 251                 int old_offset = offset;
 252
 253                 item = proto_tree_add_item(parent_tree, hf_route,
 254                                 tvb, offset, 0, FALSE);
 255                 tree = proto_item_add_subtree(item, ett_route);
 256
 257                 m0 = 0xff;
 258                 /* read the mask */
 259                 m1 = tvb_get_guint8(tvb, offset);
 260                 m2 = tvb_get_guint8(tvb, offset+1);
 261                 m3 = tvb_get_guint8(tvb, offset+2);
 262
 263                 ip = m3;
 264                 ip = (ip<<8)|m2;
 265                 ip = (ip<<8)|m1;
 266                 ip = (ip<<8)|m0;
 267                 proto_tree_add_ipv4(tree, hf_netmask, tvb, offset, 3, ip);
 268
 269                 offset += 3;
 270
 271                 /* read every srcnet, metric  pairs */
 272                 do {
 273                         int old_offset = offset;
 274                         m0 = 0xff;
 275
 276                         s0 = 0;
 277                         s1 = 0;
 278                         s2 = 0;
 279                         s3 = 0;
 280
 281                         s0 = tvb_get_guint8(tvb, offset);
 282                         offset += 1;
 283                         if (m1) {
 284                                 s1 = tvb_get_guint8(tvb, offset);
 285                                 offset += 1;
 286                         }
 287                         if (m2) {
 288                                 s2 = tvb_get_guint8(tvb, offset);
 289                                 offset += 1;
 290                         }
 291                         if (m3) {
 292                                 s3 = tvb_get_guint8(tvb, offset);
 293                                 offset += 1;
 294                         }
 295
 296                         /* handle special case for default route V3/3.4.3 */
 297                         if ((!m1)&&(!m2)&&(!m3)&&(!s0)) {
 298                                 m0 = 0;
 299                         }
 300
 301                         ip = s3;
 302                         ip = (ip<<8)|s2;
 303                         ip = (ip<<8)|s1;
 304                         ip = (ip<<8)|s0;
 305                         proto_tree_add_ipv4_format(tree, hf_saddr, tvb,
 306                                 old_offset, offset-old_offset, ip,
 307                                 "%s %d.%d.%d.%d (netmask %d.%d.%d.%d)",
 308                                 m0?"Source Network":"Default Route",
 309                                 s0,s1,s2,s3,m0,m1,m2,m3);
 310
 311                         metric = tvb_get_guint8(tvb, offset);
 312                         proto_tree_add_uint(tree, hf_metric, tvb,
 313                                 offset, 1, metric&0x7f);
 314                         offset += 1;
 315
 316
 317                 } while (!(metric&0x80));
 318
 319                 proto_item_set_len(item, offset-old_offset);
 320         }
 321
 322         return offset;
 323 }
 324
 325 int
 326 dissect_dvmrp_v3(tvbuff_t *tvb, packet_info *pinfo, proto_tree *parent_tree, int offset)
 327 {
 328         guint8 code,count;
 329
 330         /* version */
 331         proto_tree_add_uint(parent_tree, hf_version, tvb, 0, 0, 3);
 332
 333         /* type of command */
 334         proto_tree_add_uint(parent_tree, hf_type, tvb, offset, 1, 0x13);
 335         offset += 1;
 336
 337         /* code */
 338         code = tvb_get_guint8(tvb, offset);
 339         proto_tree_add_uint(parent_tree, hf_code_v3, tvb, offset, 1, code);
 340         offset += 1;
 341         if (check_col(pinfo->fd, COL_INFO)) {
 342                 col_add_fstr(pinfo->fd, COL_INFO,
 343                         "V%d %s",3 ,val_to_str(code, code_v3,
 344                                 "Unknown Type:0x%02x"));
 345         }
 346
 347         /* checksum */
 348         dvmrp_checksum(parent_tree, tvb, tvb_length_remaining(tvb, 0));
 349         offset += 2;
 350
 351         /* skip unused byte */
 352         offset += 1;
 353
 354         /* PROBE packets have capabilities flags, unused for other packets */
 355         if (code==DVMRP_V3_PROBE) {
 356                 proto_tree *tree;
 357                 proto_item *item;
 358
 359                 item = proto_tree_add_item(parent_tree, hf_capabilities,
 360                                 tvb, offset, 1, FALSE);
 361                 tree = proto_item_add_subtree(item, ett_capabilities);
 362
 363                 count = tvb_get_guint8(tvb, offset);
 364                 proto_tree_add_boolean(tree, hf_cap_netmask, tvb, offset, 1, count);
 365                 proto_tree_add_boolean(tree, hf_cap_snmp, tvb, offset, 1, count);
 366                 proto_tree_add_boolean(tree, hf_cap_mtrace, tvb, offset, 1, count);
 367                 proto_tree_add_boolean(tree, hf_cap_genid, tvb, offset, 1, count);
 368                 proto_tree_add_boolean(tree, hf_cap_prune, tvb, offset, 1, count);
 369                 proto_tree_add_boolean(tree, hf_cap_leaf, tvb, offset, 1, count);
 370         }
 371         offset += 1;
 372
 373         /* minor version */
 374         proto_tree_add_uint(parent_tree, hf_min_ver, tvb, offset, 1, tvb_get_guint8(tvb, offset));
 375         offset += 1;
 376
 377         /* major version */
 378         proto_tree_add_uint(parent_tree, hf_maj_ver, tvb, offset, 1, tvb_get_guint8(tvb, offset));
 379         offset += 1;
 380
 381         switch (code) {
 382         case DVMRP_V3_PROBE:
 383                 /* generation id */
 384                 proto_tree_add_uint(parent_tree, hf_genid, tvb,
 385                         offset, 4, tvb_get_ntohl(tvb, offset));
 386                 offset += 4;
 387                 while (tvb_length_remaining(tvb, offset)) {
 388                         proto_tree_add_ipv4(parent_tree, hf_neighbor,
 389                                 tvb, offset, 4,
 390                                 tvb_get_letohl(tvb, offset));
 391                         offset += 4;
 392                 }
 393                 break;
 394         case DVMRP_V3_REPORT:
 395                 offset = dissect_v3_report(tvb, pinfo, parent_tree, offset);
 396                 break;
 397         case DVMRP_V3_PRUNE:
 398                 /* source address */
 399                 proto_tree_add_ipv4(parent_tree, hf_saddr,
 400                         tvb, offset, 4,
 401                         tvb_get_letohl(tvb, offset));
 402                 offset += 4;
 403                 /* group address */
 404                 proto_tree_add_ipv4(parent_tree, hf_maddr,
 405                         tvb, offset, 4,
 406                         tvb_get_letohl(tvb, offset));
 407                 offset += 4;
 408                 /* prune lifetime */
 409                 proto_tree_add_uint(parent_tree, hf_life,
 410                         tvb, offset, 4,
 411                         tvb_get_ntohl(tvb, offset));
 412                 offset += 4;
 413                 /* source netmask */
 414                 if (tvb_length_remaining(tvb, offset)>=4) {
 415                         proto_tree_add_ipv4(parent_tree, hf_netmask,
 416                                 tvb, offset, 4,
 417                                 tvb_get_letohl(tvb, offset));
 418                         offset += 4;
 419                 }
 420                 break;
 421         case DVMRP_V3_GRAFT:
 422                 /* source address */
 423                 proto_tree_add_ipv4(parent_tree, hf_saddr,
 424                         tvb, offset, 4,
 425                         tvb_get_letohl(tvb, offset));
 426                 offset += 4;
 427                 /* group address */
 428                 proto_tree_add_ipv4(parent_tree, hf_maddr,
 429                         tvb, offset, 4,
 430                         tvb_get_letohl(tvb, offset));
 431                 offset += 4;
 432                 /* source netmask */
 433                 if (tvb_length_remaining(tvb, offset)>=4) {
 434                         proto_tree_add_ipv4(parent_tree, hf_netmask,
 435                                 tvb, offset, 4,
 436                                 tvb_get_letohl(tvb, offset));
 437                         offset += 4;
 438                 }
 439                 break;
 440         case DVMRP_V3_GRAFT_ACK:
 441                 /* source address */
 442                 proto_tree_add_ipv4(parent_tree, hf_saddr,
 443                         tvb, offset, 4,
 444                         tvb_get_letohl(tvb, offset));
 445                 offset += 4;
 446                 /* group address */
 447                 proto_tree_add_ipv4(parent_tree, hf_maddr,
 448                         tvb, offset, 4,
 449                         tvb_get_letohl(tvb, offset));
 450                 offset += 4;
 451                 /* source netmask */
 452                 if (tvb_length_remaining(tvb, offset)>=4) {
 453                         proto_tree_add_ipv4(parent_tree, hf_netmask,
 454                                 tvb, offset, 4,
 455                                 tvb_get_letohl(tvb, offset));
 456                         offset += 4;
 457                 }
 458                 break;
 459         }
 460
 461         return offset;
 462 }
 463
 464
 465 int
 466 dissect_dvmrp_v1(tvbuff_t *tvb, packet_info *pinfo, proto_tree *parent_tree, int offset)
 467 {
 468         guint8 code;
 469         guint8 af=2; /* default */
 470
 471         /* version */
 472         proto_tree_add_uint(parent_tree, hf_version, tvb, 0, 0, 1);
 473
 474         /* type of command */
 475         proto_tree_add_uint(parent_tree, hf_type, tvb, offset, 1, 0x13);
 476         offset += 1;
 477
 478         /* code */
 479         code = tvb_get_guint8(tvb, offset);
 480         proto_tree_add_uint(parent_tree, hf_code_v1, tvb, offset, 1, code);
 481         offset += 1;
 482         if (check_col(pinfo->fd, COL_INFO)) {
 483                 col_add_fstr(pinfo->fd, COL_INFO,
 484                         "V%d %s",1 ,val_to_str(code, code_v1,
 485                                 "Unknown Type:0x%02x"));
 486         }
 487
 488         /* checksum */
 489         dvmrp_checksum(parent_tree, tvb, tvb_length_remaining(tvb, 0));
 490         offset += 2;
 491
 492         /* decode all the v1 commands */
 493         while (tvb_length_remaining(tvb, offset)) {
 494                 proto_tree *tree;
 495                 proto_item *item;
 496                 guint8 cmd,count;
 497                 int old_offset = offset;
 498
 499                 item = proto_tree_add_item(parent_tree, hf_commands,
 500                                 tvb, offset, 0, FALSE);
 501                 tree = proto_item_add_subtree(item, ett_commands);
 502
 503                 cmd = tvb_get_guint8(tvb, offset);
 504                 proto_tree_add_uint(tree, hf_command, tvb,
 505                         offset, 1, cmd);
 506                 offset += 1;
 507
 508                 switch (cmd){
 509                 case V1_COMMAND_NULL:
 510                         offset += 1; /* skip ignored/pad byte*/
 511                         if (item) {
 512                                 proto_item_set_text(item, "Command: NULL");
 513                         }
 514                         break;
 515                 case V1_COMMAND_AFI:
 516                         af = tvb_get_guint8(tvb, offset);
 517                         proto_tree_add_uint(tree, hf_afi, tvb,
 518                                 offset, 1, af);
 519                         offset += 1;
 520                         if (item) {
 521                                 proto_item_set_text(item, "%s: %s",
 522                                         val_to_str(cmd, command, "Unknown Command:0x%02x"),
 523                                         val_to_str(af, afi, "Unknown Family:0x%02x")
 524                                 );
 525                         }
 526                         break;
 527                 case V1_COMMAND_SUBNETMASK:
 528                         count = tvb_get_guint8(tvb, offset);
 529                         proto_tree_add_uint(tree, hf_count, tvb,
 530                                 offset, 1, count);
 531                         offset += 1;
 532                         if (count) { /* must be 0 or 1 */
 533                                 proto_tree_add_ipv4(tree, hf_netmask,
 534                                         tvb, offset, 4,
 535                                         tvb_get_letohl(tvb, offset));
 536                                 if (item) {
 537                                         proto_item_set_text(item, "%s: %d.%d.%d.%d",
 538                                                 val_to_str(cmd, command, "Unknown Command:0x%02x"),
 539                                                 tvb_get_guint8(tvb, offset),
 540                                                 tvb_get_guint8(tvb, offset+1),
 541                                                 tvb_get_guint8(tvb, offset+2),
 542                                                 tvb_get_guint8(tvb, offset+3));
 543                                 }
 544                                 offset += 4;
 545                         } else {
 546                                 if (item) {
 547                                         proto_item_set_text(item, "%s: <no mask supplied>",
 548                                                 val_to_str(cmd, command, "Unknown Command:0x%02x"));
 549                                 }
 550                         }
 551                         break;
 552                 case V1_COMMAND_METRIC:
 553                         proto_tree_add_uint(tree, hf_metric, tvb,
 554                                 offset, 1, tvb_get_guint8(tvb, offset));
 555                         if (item) {
 556                                 proto_item_set_text(item, "%s: %d",
 557                                         val_to_str(cmd, command, "Unknown Command:0x%02x"),
 558                                         tvb_get_guint8(tvb, offset));
 559                         }
 560                         offset += 1;
 561                         break;
 562                 case V1_COMMAND_FLAGS0:
 563                         count = tvb_get_guint8(tvb, offset);
 564                         proto_tree_add_boolean(tree, hf_dest_unr, tvb, offset, 1, count);
 565                         proto_tree_add_boolean(tree, hf_split_horiz, tvb, offset, 1, count);
 566                         if (item) {
 567                                 proto_item_set_text(item, "%s: 0x%02x",
 568                                         val_to_str(cmd, command, "Unknown Command:0x%02x"), count);
 569                         }
 570                         offset += 1;
 571                         break;
 572                 case V1_COMMAND_INFINITY:
 573                         proto_tree_add_uint(tree, hf_infinity, tvb,
 574                                 offset, 1, tvb_get_guint8(tvb, offset));
 575                         if (item) {
 576                                 proto_item_set_text(item, "%s: %d",
 577                                         val_to_str(cmd, command, "Unknown Command:0x%02x"), tvb_get_guint8(tvb, offset));
 578                         }
 579                         offset += 1;
 580                         break;
 581                 case V1_COMMAND_DA:
 582                 case V1_COMMAND_RDA: /* same as DA */
 583                         count = tvb_get_guint8(tvb, offset);
 584                         proto_tree_add_uint(tree, hf_count, tvb,
 585                                 offset, 1, count);
 586                         offset += 1;
 587                         while (count--) {
 588                                 proto_tree_add_ipv4(tree, hf_daddr,
 589                                         tvb, offset, 4,
 590                                         tvb_get_letohl(tvb, offset));
 591                                 offset += 4;
 592                         }
 593                         if (item) {
 594                                 proto_item_set_text(item, "%s",
 595                                         val_to_str(cmd, command, "Unknown Command:0x%02x"));
 596                         }
 597                         break;
 598                 case V1_COMMAND_NMR:
 599                         count = tvb_get_guint8(tvb, offset);
 600                         proto_tree_add_uint(tree, hf_count, tvb,
 601                                 offset, 1, count);
 602                         offset += 1;
 603                         while (count--) {
 604                                 proto_tree_add_ipv4(tree, hf_maddr,
 605                                         tvb, offset, 4,
 606                                         tvb_get_letohl(tvb, offset));
 607                                 offset += 4;
 608                                 proto_tree_add_uint(tree, hf_hold, tvb,
 609                                         offset, 4, tvb_get_ntohl(tvb, offset));
 610                                 offset += 4;
 611                         }
 612                         if (item) {
 613                                 proto_item_set_text(item, "%s",
 614                                         val_to_str(cmd, command, "Unknown Command:0x%02x"));
 615                         }
 616                         break;
 617                 case V1_COMMAND_NMR_CANCEL:
 618                         count = tvb_get_guint8(tvb, offset);
 619                         proto_tree_add_uint(tree, hf_count, tvb,
 620                                 offset, 1, count);
 621                         offset += 1;
 622                         while (count--) {
 623                                 proto_tree_add_ipv4(tree, hf_maddr,
 624                                         tvb, offset, 4,
 625                                         tvb_get_letohl(tvb, offset));
 626                                 offset += 4;
 627                         }
 628                         if (item) {
 629                                 proto_item_set_text(item, "%s",
 630                                         val_to_str(cmd, command, "Unknown Command:0x%02x"));
 631                         }
 632                         break;
 633                 }
 634
 635                 proto_item_set_len(item, offset-old_offset);
 636         }
 637
 638         return offset;
 639 }
 640
 641 /* This function is only called from the IGMP dissector */
 642 int
 643 dissect_dvmrp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *parent_tree, int offset)
 644 {
 645         proto_tree *tree;
 646         proto_item *item;
 647
 648         if (!proto_is_protocol_enabled(proto_dvmrp)) {
 649                 /* we are not enabled, skip entire packet to be nice
 650                    to the igmp layer. (so clicking on IGMP will display the data)
 651                  */
 652                 return offset+tvb_length_remaining(tvb, offset);
 653         }
 654
 655         item = proto_tree_add_item(parent_tree, proto_dvmrp, tvb, offset, 0, FALSE);
 656         tree = proto_item_add_subtree(item, ett_dvmrp);
 657
 658
 659         if (check_col(pinfo->fd, COL_PROTOCOL)) {
 660                 col_set_str(pinfo->fd, COL_PROTOCOL, "DVMRP");
 661         }
 662         if (check_col(pinfo->fd, COL_INFO)) {
 663                 col_clear(pinfo->fd, COL_INFO);
 664         }
 665
 666
 667         if ((tvb_length_remaining(tvb, offset)>=8)
 668          && (tvb_get_guint8(tvb, 6)==0xff)
 669          && (tvb_get_guint8(tvb, 7)==0x03)) {
 670                 offset = dissect_dvmrp_v3(tvb, pinfo, tree, offset);
 671                 proto_item_set_len(item, offset);
 672                 return offset;
 673         }
 674
 675
 676         offset = dissect_dvmrp_v1(tvb, pinfo, tree, offset);
 677         proto_item_set_len(item, offset);
 678         return offset;
 679 }
 680
 681 void
 682 proto_register_dvmrp(void)
 683 {
 684         static hf_register_info hf[] = {
 685                 { &hf_version,
 686                         { "DVMRP Version", "dvmrp.version", FT_UINT8, BASE_DEC,
 687                           NULL, 0, "DVMRP Version", HFILL }},
 688
 689                 { &hf_type,
 690                         { "Type", "dvmrp.type", FT_UINT8, BASE_HEX,
 691                           VALS(dvmrp_type), 0, "DVMRP Packet Type", HFILL }},
 692
 693                 { &hf_code_v1,
 694                         { "Code", "dvmrp.v1.code", FT_UINT8, BASE_HEX,
 695                           VALS(code_v1), 0, "DVMRP Packet Code", HFILL }},
 696
 697                 { &hf_checksum,
 698                         { "Checksum", "dvmrp.checksum", FT_UINT16, BASE_HEX,
 699                           NULL, 0, "DVMRP Checksum", HFILL }},
 700
 701                 { &hf_checksum_bad,
 702                         { "Bad Checksum", "dvmrp.checksum_bad", FT_BOOLEAN, BASE_NONE,
 703                           NULL, 0, "Bad DVMRP Checksum", HFILL }},
 704
 705                 { &hf_commands,
 706                         { "Commands", "dvmrp.commands", FT_NONE, BASE_NONE,
 707                           NULL, 0, "DVMRP V1 Commands", HFILL }},
 708
 709                 { &hf_command,
 710                         { "Command", "dvmrp.command", FT_UINT8, BASE_HEX,
 711                           VALS(command), 0, "DVMRP V1 Command", HFILL }},
 712
 713                 { &hf_afi,
 714                         { "Address Family", "dvmrp.afi", FT_UINT8, BASE_HEX,
 715                           VALS(afi), 0, "DVMRP Address Family Indicator", HFILL }},
 716
 717                 { &hf_count,
 718                         { "Count", "dvmrp.count", FT_UINT8, BASE_HEX,
 719                           NULL, 0, "Count", HFILL }},
 720
 721                 { &hf_netmask,
 722                         { "Netmask", "igmp.netmask", FT_IPv4, BASE_NONE,
 723                           NULL, 0, "DVMRP Netmask", HFILL }},
 724
 725                 { &hf_metric,
 726                         { "Metric", "dvmrp.metric", FT_UINT8, BASE_DEC,
 727                           NULL, 0, "DVMRP Metric", HFILL }},
 728
 729                 {&hf_dest_unr,
 730                         { "Destination Unreachable", "dvmrp.dest_unreach", FT_BOOLEAN, 8,
 731                         TFS(&tfs_dest_unreach), 0x01, "Destination Unreachable", HFILL }},
 732
 733                 {&hf_split_horiz,
 734                         { "Split Horizon", "dvmrp.split_horiz", FT_BOOLEAN, 8,
 735                         TFS(&tfs_split_horiz), 0x02, "Split Horizon concealed route", HFILL }},
 736
 737                 { &hf_infinity,
 738                         { "Infinity", "dvmrp.infinity", FT_UINT8, BASE_DEC,
 739                           NULL, 0, "DVMRP Infinity", HFILL }},
 740
 741                 { &hf_daddr,
 742                         { "Dest Addr", "igmp.daddr", FT_IPv4, BASE_NONE,
 743                           NULL, 0, "DVMRP Destination Address", HFILL }},
 744
 745                 { &hf_maddr,
 746                         { "Multicast Addr", "igmp.maddr", FT_IPv4, BASE_NONE,
 747                           NULL, 0, "DVMRP Multicast Address", HFILL }},
 748
 749                 { &hf_hold,
 750                         { "Hold Time", "dvmrp.hold", FT_UINT32, BASE_DEC,
 751                           NULL, 0, "DVMRP Hold Time in seconds", HFILL }},
 752
 753                 { &hf_code_v3,
 754                         { "Code", "dvmrp.v3.code", FT_UINT8, BASE_HEX,
 755                           VALS(code_v3), 0, "DVMRP Packet Code", HFILL }},
 756
 757                 { &hf_capabilities,
 758                         { "Capabilities", "dvmrp.capabilities", FT_NONE, BASE_NONE,
 759                           NULL, 0, "DVMRP V3 Capabilities", HFILL }},
 760
 761                 {&hf_cap_leaf,
 762                         { "Leaf", "dvmrp.cap.leaf", FT_BOOLEAN, 8,
 763                         TFS(&tfs_cap_leaf), DVMRP_V3_CAP_LEAF, "Leaf", HFILL }},
 764
 765                 {&hf_cap_prune,
 766                         { "Prune", "dvmrp.cap.prune", FT_BOOLEAN, 8,
 767                         TFS(&tfs_cap_prune), DVMRP_V3_CAP_PRUNE, "Prune capability", HFILL }},
 768
 769                 {&hf_cap_genid,
 770                         { "Genid", "dvmrp.cap.genid", FT_BOOLEAN, 8,
 771                         TFS(&tfs_cap_genid), DVMRP_V3_CAP_GENID, "Genid capability", HFILL }},
 772
 773                 {&hf_cap_mtrace,
 774                         { "Mtrace", "dvmrp.cap.mtrace", FT_BOOLEAN, 8,
 775                         TFS(&tfs_cap_mtrace), DVMRP_V3_CAP_MTRACE, "Mtrace capability", HFILL }},
 776
 777                 {&hf_cap_snmp,
 778                         { "SNMP", "dvmrp.cap.snmp", FT_BOOLEAN, 8,
 779                         TFS(&tfs_cap_snmp), DVMRP_V3_CAP_SNMP, "SNMP capability", HFILL }},
 780
 781                 {&hf_cap_netmask,
 782                         { "Netmask", "dvmrp.cap.netmask", FT_BOOLEAN, 8,
 783                         TFS(&tfs_cap_netmask), DVMRP_V3_CAP_NETMASK, "Netmask capability", HFILL }},
 784
 785                 { &hf_min_ver,
 786                         { "Minor Version", "dvmrp.min_ver", FT_UINT8, BASE_HEX,
 787                           NULL, 0, "DVMRP Minor Version", HFILL }},
 788
 789                 { &hf_maj_ver,
 790                         { "Major Version", "dvmrp.maj_ver", FT_UINT8, BASE_HEX,
 791                           NULL, 0, "DVMRP Major Version", HFILL }},
 792
 793                 { &hf_genid,
 794                         { "Generation ID", "dvmrp.genid", FT_UINT32, BASE_DEC,
 795                           NULL, 0, "DVMRP Generation ID", HFILL }},
 796
 797                 { &hf_naddr,
 798                         { "Neighbor Addr", "igmp.naddr", FT_IPv4, BASE_NONE,
 799                           NULL, 0, "DVMRP Neighbor Address", HFILL }},
 800
 801                 { &hf_route,
 802                         { "Route", "dvmrp.route", FT_NONE, BASE_NONE,
 803                           NULL, 0, "DVMRP V3 Route Report", HFILL }},
 804
 805                 { &hf_saddr,
 806                         { "Source Addr", "igmp.saddr", FT_IPv4, BASE_NONE,
 807                           NULL, 0, "DVMRP Source Address", HFILL }},
 808
 809                 { &hf_life,
 810                         { "Prune lifetime", "dvmrp.lifetime", FT_UINT32, BASE_DEC,
 811                           NULL, 0, "DVMRP Prune Lifetime", HFILL }},
 812
 813                 { &hf_neighbor,
 814                         { "Neighbor Addr", "igmp.neighbor", FT_IPv4, BASE_NONE,
 815                           NULL, 0, "DVMRP Neighbor Address", HFILL }},
 816
 817         };
 818         static gint *ett[] = {
 819                 &ett_dvmrp,
 820                 &ett_commands,
 821                 &ett_capabilities,
 822                 &ett_route,
 823         };
 824
 825         proto_dvmrp = proto_register_protocol("Distance Vector Multicast Routing Protocol",
 826             "DVMRP", "dvmrp");
 827         proto_register_field_array(proto_dvmrp, hf, array_length(hf));
 828         proto_register_subtree_array(ett, array_length(ett));
 829 }
 830