packet-rip.c

   1 /* packet-rip.c
   2  * Routines for RIPv1 and RIPv2 packet disassembly
   3  * RFC1058, RFC2453
   4  * (c) Copyright Hannes R. Boehm <hannes@boehm.org>
   5  *
   6  * $Id: packet-rip.c,v 1.33 2002/08/28 21:00:29 jmayer Exp $
   7  *
   8  * Ethereal - Network traffic analyzer
   9  * By Gerald Combs <gerald@ethereal.com>
  10  * Copyright 1998 Gerald Combs
  11  *
  12  * This program is free software; you can redistribute it and/or
  13  * modify it under the terms of the GNU General Public License
  14  * as published by the Free Software Foundation; either version 2
  15  * of the License, or (at your option) any later version.
  16  *
  17  * This program is distributed in the hope that it will be useful,
  18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20  * GNU General Public License for more details.
  21  *
  22  * You should have received a copy of the GNU General Public License
  23  * along with this program; if not, write to the Free Software
  24  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  25  */
  26
  27 #include "config.h"
  28
  29 #include <string.h>
  30 #include <glib.h>
  31 #include <epan/packet.h>
  32
  33 #define UDP_PORT_RIP    520
  34
  35 #define RIPv1   1
  36 #define RIPv2   2
  37
  38 static const value_string version_vals[] = {
  39         { RIPv1, "RIPv1" },
  40         { RIPv2, "RIPv2" },
  41         { 0,     NULL }
  42 };
  43
  44 static const value_string command_vals[] = {
  45         { 1, "Request" },
  46         { 2, "Response" },
  47         { 3, "Traceon" },
  48         { 4, "Traceoff" },
  49         { 5, "Vendor specific (Sun)" },
  50         { 0, NULL }
  51 };
  52
  53 #define AFVAL_UNSPEC    0
  54 #define AFVAL_IP        2
  55
  56 static const value_string family_vals[] = {
  57         { AFVAL_UNSPEC, "Unspecified" },
  58         { AFVAL_IP,     "IP" },
  59         { 0,            NULL }
  60 };
  61
  62 #define RIP_HEADER_LENGTH 4
  63 #define RIP_ENTRY_LENGTH 20
  64
  65 static int proto_rip = -1;
  66 static int hf_rip_command = -1;
  67 static int hf_rip_version = -1;
  68 static int hf_rip_routing_domain = -1;
  69 static int hf_rip_ip = -1;
  70 static int hf_rip_netmask = -1;
  71 static int hf_rip_next_hop = -1;
  72 static int hf_rip_metric = -1;
  73 static int hf_rip_auth = -1;
  74 static int hf_rip_auth_passwd = -1;
  75 static int hf_rip_family = -1;
  76 static int hf_rip_route_tag = -1;
  77
  78 static gint ett_rip = -1;
  79 static gint ett_rip_vec = -1;
  80
  81 static void dissect_unspec_rip_vektor(tvbuff_t *tvb, int offset, guint8 version,
  82     proto_tree *tree);
  83 static void dissect_ip_rip_vektor(tvbuff_t *tvb, int offset, guint8 version,
  84     proto_tree *tree);
  85 static void dissect_rip_authentication(tvbuff_t *tvb, int offset,
  86     proto_tree *tree);
  87
  88 static void
  89 dissect_rip(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
  90 {
  91     int offset = 0;
  92     proto_tree *rip_tree = NULL;
  93     proto_item *ti;
  94     guint8 command;
  95     guint8 version;
  96     guint16 family;
  97
  98     if (check_col(pinfo->cinfo, COL_PROTOCOL))
  99         col_set_str(pinfo->cinfo, COL_PROTOCOL, "RIP");
 100     if (check_col(pinfo->cinfo, COL_INFO))
 101         col_clear(pinfo->cinfo, COL_INFO);
 102
 103     command = tvb_get_guint8(tvb, 0);
 104     version = tvb_get_guint8(tvb, 1);
 105
 106     if (check_col(pinfo->cinfo, COL_PROTOCOL))
 107         col_add_str(pinfo->cinfo, COL_PROTOCOL,
 108                     val_to_str(version, version_vals, "RIP"));
 109     if (check_col(pinfo->cinfo, COL_INFO))
 110         col_add_str(pinfo->cinfo, COL_INFO,
 111                     val_to_str(command, command_vals, "Unknown command (%u)"));
 112
 113     if (tree) {
 114         ti = proto_tree_add_item(tree, proto_rip, tvb, 0, -1, FALSE);
 115         rip_tree = proto_item_add_subtree(ti, ett_rip);
 116
 117         proto_tree_add_uint(rip_tree, hf_rip_command, tvb, 0, 1, command);
 118         proto_tree_add_uint(rip_tree, hf_rip_version, tvb, 1, 1, version);
 119         if (version == RIPv2)
 120             proto_tree_add_uint(rip_tree, hf_rip_routing_domain, tvb, 2, 2,
 121                         tvb_get_ntohs(tvb, 2));
 122
 123         /* skip header */
 124         offset = RIP_HEADER_LENGTH;
 125
 126         /* zero or more entries */
 127         while (tvb_reported_length_remaining(tvb, offset) > 0) {
 128             family = tvb_get_ntohs(tvb, offset);
 129             switch (family) {
 130             case AFVAL_UNSPEC: /* Unspecified */
 131                 /*
 132                  * There should be one entry in the request, and a metric
 133                  * of infinity, meaning "show the entire routing table".
 134                  */
 135                 dissect_unspec_rip_vektor(tvb, offset, version, rip_tree);
 136                 break;
 137             case AFVAL_IP: /* IP */
 138                 dissect_ip_rip_vektor(tvb, offset, version, rip_tree);
 139                 break;
 140             case 0xFFFF:
 141                 dissect_rip_authentication(tvb, offset, rip_tree);
 142                 break;
 143             default:
 144                 proto_tree_add_text(rip_tree, tvb, offset,
 145                                 RIP_ENTRY_LENGTH, "Unknown address family %u",
 146                                 family);
 147                 break;
 148             }
 149
 150             offset += RIP_ENTRY_LENGTH;
 151         }
 152     }
 153 }
 154
 155 static void
 156 dissect_unspec_rip_vektor(tvbuff_t *tvb, int offset, guint8 version,
 157                       proto_tree *tree)
 158 {
 159     proto_item *ti;
 160     proto_tree *rip_vektor_tree;
 161     guint32 metric;
 162
 163     metric = tvb_get_ntohl(tvb, offset+16);
 164     ti = proto_tree_add_text(tree, tvb, offset,
 165                              RIP_ENTRY_LENGTH, "Address not specified, Metric: %u",
 166                              metric);
 167     rip_vektor_tree = proto_item_add_subtree(ti, ett_rip_vec);
 168
 169     proto_tree_add_item(rip_vektor_tree, hf_rip_family, tvb, offset, 2, FALSE);
 170     if (version == RIPv2) {
 171         proto_tree_add_item(rip_vektor_tree, hf_rip_route_tag, tvb, offset+2, 2,
 172                         FALSE);
 173         proto_tree_add_item(rip_vektor_tree, hf_rip_netmask, tvb, offset+8, 4,
 174                             FALSE);
 175         proto_tree_add_item(rip_vektor_tree, hf_rip_next_hop, tvb, offset+12, 4,
 176                             FALSE);
 177     }
 178     proto_tree_add_uint(rip_vektor_tree, hf_rip_metric, tvb,
 179                         offset+16, 4, metric);
 180 }
 181
 182 static void
 183 dissect_ip_rip_vektor(tvbuff_t *tvb, int offset, guint8 version,
 184                       proto_tree *tree)
 185 {
 186     proto_item *ti;
 187     proto_tree *rip_vektor_tree;
 188     guint32 metric;
 189
 190     metric = tvb_get_ntohl(tvb, offset+16);
 191     ti = proto_tree_add_text(tree, tvb, offset,
 192                              RIP_ENTRY_LENGTH, "IP Address: %s, Metric: %u",
 193                              ip_to_str(tvb_get_ptr(tvb, offset+4, 4)), metric);
 194     rip_vektor_tree = proto_item_add_subtree(ti, ett_rip_vec);
 195
 196     proto_tree_add_item(rip_vektor_tree, hf_rip_family, tvb, offset, 2, FALSE);
 197     if (version == RIPv2) {
 198         proto_tree_add_item(rip_vektor_tree, hf_rip_route_tag, tvb, offset+2, 2,
 199                         FALSE);
 200     }
 201
 202     proto_tree_add_item(rip_vektor_tree, hf_rip_ip, tvb, offset+4, 4, FALSE);
 203
 204     if (version == RIPv2) {
 205         proto_tree_add_item(rip_vektor_tree, hf_rip_netmask, tvb, offset+8, 4,
 206                             FALSE);
 207         proto_tree_add_item(rip_vektor_tree, hf_rip_next_hop, tvb, offset+12, 4,
 208                             FALSE);
 209     }
 210     proto_tree_add_uint(rip_vektor_tree, hf_rip_metric, tvb,
 211                         offset+16, 4, metric);
 212 }
 213
 214 static void
 215 dissect_rip_authentication(tvbuff_t *tvb, int offset, proto_tree *tree)
 216 {
 217     proto_item *ti;
 218     proto_tree *rip_authentication_tree;
 219     guint16 authtype;
 220
 221     ti = proto_tree_add_text(tree, tvb, offset, RIP_ENTRY_LENGTH,
 222                              "Authentication");
 223     rip_authentication_tree = proto_item_add_subtree(ti, ett_rip_vec);
 224
 225     authtype = tvb_get_ntohs(tvb, offset + 2);
 226     proto_tree_add_uint(rip_authentication_tree, hf_rip_auth, tvb, offset+2, 2,
 227                 authtype);
 228     if (authtype == 2) {
 229         proto_tree_add_item(rip_authentication_tree, hf_rip_auth_passwd,
 230                         tvb, offset+4, 16, FALSE);
 231     }
 232 }
 233
 234 void
 235 proto_register_rip(void)
 236 {
 237         static hf_register_info hf[] = {
 238                 { &hf_rip_command,
 239                         { "Command", "rip.command", FT_UINT8, BASE_DEC,
 240                         VALS(command_vals), 0, "What type of RIP Command is this", HFILL }},
 241
 242                 { &hf_rip_version,
 243                         { "Version", "rip.version", FT_UINT8, BASE_DEC,
 244                         VALS(version_vals), 0, "Version of the RIP protocol", HFILL }},
 245
 246                 { &hf_rip_family,
 247                         { "Address Family", "rip.family", FT_UINT16, BASE_DEC,
 248                         VALS(family_vals), 0, "Address family", HFILL }},
 249
 250                 { &hf_rip_routing_domain,
 251                         { "Routing Domain", "rip.routing_domain", FT_UINT16, BASE_DEC,
 252                         NULL, 0, "RIPv2 Routing Domain", HFILL }},
 253
 254                 { &hf_rip_ip,
 255                         { "IP Address", "rip.ip", FT_IPv4, BASE_NONE,
 256                         NULL, 0, "IP Address", HFILL}},
 257
 258                 { &hf_rip_netmask,
 259                         { "Netmask", "rip.netmask", FT_IPv4, BASE_NONE,
 260                         NULL, 0, "Netmask", HFILL}},
 261
 262                 { &hf_rip_next_hop,
 263                         { "Next Hop", "rip.next_hop", FT_IPv4, BASE_NONE,
 264                         NULL, 0, "Next Hop router for this route", HFILL}},
 265
 266                 { &hf_rip_metric,
 267                         { "Metric", "rip.metric", FT_UINT16, BASE_DEC,
 268                         NULL, 0, "Metric for this route", HFILL }},
 269
 270                 { &hf_rip_auth,
 271                         { "Authentication type", "rip.auth.type", FT_UINT16, BASE_DEC,
 272                         NULL, 0, "Type of authentication", HFILL }},
 273
 274                 { &hf_rip_auth_passwd,
 275                         { "Password", "rip.auth.passwd", FT_STRING, BASE_DEC,
 276                         NULL, 0, "Authentication password", HFILL }},
 277
 278                 { &hf_rip_route_tag,
 279                         { "Route Tag", "rip.route_tag", FT_UINT16, BASE_DEC,
 280                         NULL, 0, "Route Tag", HFILL }},
 281
 282         };
 283         static gint *ett[] = {
 284                 &ett_rip,
 285                 &ett_rip_vec,
 286         };
 287
 288         proto_rip = proto_register_protocol("Routing Information Protocol",
 289                                 "RIP", "rip");
 290         proto_register_field_array(proto_rip, hf, array_length(hf));
 291         proto_register_subtree_array(ett, array_length(ett));
 292 }
 293
 294 void
 295 proto_reg_handoff_rip(void)
 296 {
 297         dissector_handle_t rip_handle;
 298
 299         rip_handle = create_dissector_handle(dissect_rip, proto_rip);
 300         dissector_add("udp.port", UDP_PORT_RIP, rip_handle);
 301 }