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 1.31 2002/04/04 23:20:33 guy 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 #ifdef HAVE_SYS_TYPES_H
  30 #include <sys/types.h>
  31 #endif
  32
  33 #ifdef HAVE_NETINET_IN_H
  34 #include <netinet/in.h>
  35 #endif
  36
  37 #include <string.h>
  38 #include <glib.h>
  39 #include <epan/packet.h>
  40
  41 #define UDP_PORT_RIP    520
  42
  43 #define RIPv1   1
  44 #define RIPv2   2
  45
  46 static const value_string version_vals[] = {
  47         { RIPv1, "RIPv1" },
  48         { RIPv2, "RIPv2" },
  49         { 0,     NULL }
  50 };
  51
  52 static const value_string command_vals[] = {
  53         { 1, "Request" },
  54         { 2, "Response" },
  55         { 3, "Traceon" },
  56         { 4, "Traceoff" },
  57         { 5, "Vendor specific (Sun)" },
  58         { 0, NULL }
  59 };
  60
  61 #define AFVAL_UNSPEC    0
  62 #define AFVAL_IP        2
  63
  64 static const value_string family_vals[] = {
  65         { AFVAL_UNSPEC, "Unspecified" },
  66         { AFVAL_IP,     "IP" },
  67         { 0,            NULL }
  68 };
  69
  70 #define RIP_HEADER_LENGTH 4
  71 #define RIP_ENTRY_LENGTH 20
  72
  73 static int proto_rip = -1;
  74 static int hf_rip_command = -1;
  75 static int hf_rip_version = -1;
  76 static int hf_rip_routing_domain = -1;
  77 static int hf_rip_ip = -1;
  78 static int hf_rip_netmask = -1;
  79 static int hf_rip_next_hop = -1;
  80 static int hf_rip_metric = -1;
  81 static int hf_rip_auth = -1;
  82 static int hf_rip_auth_passwd = -1;
  83 static int hf_rip_family = -1;
  84 static int hf_rip_route_tag = -1;
  85
  86 static gint ett_rip = -1;
  87 static gint ett_rip_vec = -1;
  88
  89 static void dissect_unspec_rip_vektor(tvbuff_t *tvb, int offset, guint8 version,
  90     proto_tree *tree);
  91 static void dissect_ip_rip_vektor(tvbuff_t *tvb, int offset, guint8 version,
  92     proto_tree *tree);
  93 static void dissect_rip_authentication(tvbuff_t *tvb, int offset,
  94     proto_tree *tree);
  95
  96 static void
  97 dissect_rip(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
  98 {
  99     int offset = 0;
 100     proto_tree *rip_tree = NULL;
 101     proto_item *ti;
 102     guint8 command;
 103     guint8 version;
 104     guint16 family;
 105
 106     if (check_col(pinfo->cinfo, COL_PROTOCOL))
 107         col_set_str(pinfo->cinfo, COL_PROTOCOL, "RIP");
 108     if (check_col(pinfo->cinfo, COL_INFO))
 109         col_clear(pinfo->cinfo, COL_INFO);
 110
 111     command = tvb_get_guint8(tvb, 0);
 112     version = tvb_get_guint8(tvb, 1);
 113
 114     if (check_col(pinfo->cinfo, COL_PROTOCOL))
 115         col_add_str(pinfo->cinfo, COL_PROTOCOL,
 116                     val_to_str(version, version_vals, "RIP"));
 117     if (check_col(pinfo->cinfo, COL_INFO))
 118         col_add_str(pinfo->cinfo, COL_INFO,
 119                     val_to_str(command, command_vals, "Unknown command (%u)"));
 120
 121     if (tree) {
 122         ti = proto_tree_add_item(tree, proto_rip, tvb, 0, -1, FALSE);
 123         rip_tree = proto_item_add_subtree(ti, ett_rip);
 124
 125         proto_tree_add_uint(rip_tree, hf_rip_command, tvb, 0, 1, command);
 126         proto_tree_add_uint(rip_tree, hf_rip_version, tvb, 1, 1, version);
 127         if (version == RIPv2)
 128             proto_tree_add_uint(rip_tree, hf_rip_routing_domain, tvb, 2, 2,
 129                         tvb_get_ntohs(tvb, 2));
 130
 131         /* skip header */
 132         offset = RIP_HEADER_LENGTH;
 133
 134         /* zero or more entries */
 135         while (tvb_reported_length_remaining(tvb, offset) > 0) {
 136             family = tvb_get_ntohs(tvb, offset);
 137             switch (family) {
 138             case AFVAL_UNSPEC: /* Unspecified */
 139                 /*
 140                  * There should be one entry in the request, and a metric
 141                  * of infinity, meaning "show the entire routing table".
 142                  */
 143                 dissect_unspec_rip_vektor(tvb, offset, version, rip_tree);
 144                 break;
 145             case AFVAL_IP: /* IP */
 146                 dissect_ip_rip_vektor(tvb, offset, version, rip_tree);
 147                 break;
 148             case 0xFFFF:
 149                 dissect_rip_authentication(tvb, offset, rip_tree);
 150                 break;
 151             default:
 152                 proto_tree_add_text(rip_tree, tvb, offset,
 153                                 RIP_ENTRY_LENGTH, "Unknown address family %u",
 154                                 family);
 155                 break;
 156             }
 157
 158             offset += RIP_ENTRY_LENGTH;
 159         }
 160     }
 161 }
 162
 163 static void
 164 dissect_unspec_rip_vektor(tvbuff_t *tvb, int offset, guint8 version,
 165                       proto_tree *tree)
 166 {
 167     proto_item *ti;
 168     proto_tree *rip_vektor_tree;
 169     guint32 metric;
 170
 171     metric = tvb_get_ntohl(tvb, offset+16);
 172     ti = proto_tree_add_text(tree, tvb, offset,
 173                              RIP_ENTRY_LENGTH, "Address not specified, Metric: %u",
 174                              metric);
 175     rip_vektor_tree = proto_item_add_subtree(ti, ett_rip_vec);
 176
 177     proto_tree_add_item(rip_vektor_tree, hf_rip_family, tvb, offset, 2, FALSE);
 178     if (version == RIPv2) {
 179         proto_tree_add_item(rip_vektor_tree, hf_rip_route_tag, tvb, offset+2, 2,
 180                         FALSE);
 181         proto_tree_add_item(rip_vektor_tree, hf_rip_netmask, tvb, offset+8, 4,
 182                             FALSE);
 183         proto_tree_add_item(rip_vektor_tree, hf_rip_next_hop, tvb, offset+12, 4,
 184                             FALSE);
 185     }
 186     proto_tree_add_uint(rip_vektor_tree, hf_rip_metric, tvb,
 187                         offset+16, 4, metric);
 188 }
 189
 190 static void
 191 dissect_ip_rip_vektor(tvbuff_t *tvb, int offset, guint8 version,
 192                       proto_tree *tree)
 193 {
 194     proto_item *ti;
 195     proto_tree *rip_vektor_tree;
 196     guint32 metric;
 197
 198     metric = tvb_get_ntohl(tvb, offset+16);
 199     ti = proto_tree_add_text(tree, tvb, offset,
 200                              RIP_ENTRY_LENGTH, "IP Address: %s, Metric: %u",
 201                              ip_to_str(tvb_get_ptr(tvb, offset+4, 4)), metric);
 202     rip_vektor_tree = proto_item_add_subtree(ti, ett_rip_vec);
 203
 204     proto_tree_add_item(rip_vektor_tree, hf_rip_family, tvb, offset, 2, FALSE);
 205     if (version == RIPv2) {
 206         proto_tree_add_item(rip_vektor_tree, hf_rip_route_tag, tvb, offset+2, 2,
 207                         FALSE);
 208     }
 209
 210     proto_tree_add_item(rip_vektor_tree, hf_rip_ip, tvb, offset+4, 4, FALSE);
 211
 212     if (version == RIPv2) {
 213         proto_tree_add_item(rip_vektor_tree, hf_rip_netmask, tvb, offset+8, 4,
 214                             FALSE);
 215         proto_tree_add_item(rip_vektor_tree, hf_rip_next_hop, tvb, offset+12, 4,
 216                             FALSE);
 217     }
 218     proto_tree_add_uint(rip_vektor_tree, hf_rip_metric, tvb,
 219                         offset+16, 4, metric);
 220 }
 221
 222 static void
 223 dissect_rip_authentication(tvbuff_t *tvb, int offset, proto_tree *tree)
 224 {
 225     proto_item *ti;
 226     proto_tree *rip_authentication_tree;
 227     guint16 authtype;
 228
 229     ti = proto_tree_add_text(tree, tvb, offset, RIP_ENTRY_LENGTH,
 230                              "Authentication");
 231     rip_authentication_tree = proto_item_add_subtree(ti, ett_rip_vec);
 232
 233     authtype = tvb_get_ntohs(tvb, offset + 2);
 234     proto_tree_add_uint(rip_authentication_tree, hf_rip_auth, tvb, offset+2, 2,
 235                 authtype);
 236     if (authtype == 2) {
 237         proto_tree_add_item(rip_authentication_tree, hf_rip_auth_passwd,
 238                         tvb, offset+4, 16, FALSE);
 239     }
 240 }
 241
 242 void
 243 proto_register_rip(void)
 244 {
 245         static hf_register_info hf[] = {
 246                 { &hf_rip_command,
 247                         { "Command", "rip.command", FT_UINT8, BASE_DEC,
 248                         VALS(command_vals), 0, "What type of RIP Command is this", HFILL }},
 249
 250                 { &hf_rip_version,
 251                         { "Version", "rip.version", FT_UINT8, BASE_DEC,
 252                         VALS(version_vals), 0, "Version of the RIP protocol", HFILL }},
 253
 254                 { &hf_rip_family,
 255                         { "Address Family", "rip.family", FT_UINT16, BASE_DEC,
 256                         VALS(family_vals), 0, "Address family", HFILL }},
 257
 258                 { &hf_rip_routing_domain,
 259                         { "Routing Domain", "rip.routing_domain", FT_UINT16, BASE_DEC,
 260                         NULL, 0, "RIPv2 Routing Domain", HFILL }},
 261
 262                 { &hf_rip_ip,
 263                         { "IP Address", "rip.ip", FT_IPv4, BASE_NONE,
 264                         NULL, 0, "IP Address", HFILL}},
 265
 266                 { &hf_rip_netmask,
 267                         { "Netmask", "rip.netmask", FT_IPv4, BASE_NONE,
 268                         NULL, 0, "Netmask", HFILL}},
 269
 270                 { &hf_rip_next_hop,
 271                         { "Next Hop", "rip.next_hop", FT_IPv4, BASE_NONE,
 272                         NULL, 0, "Next Hop router for this route", HFILL}},
 273
 274                 { &hf_rip_metric,
 275                         { "Metric", "rip.metric", FT_UINT16, BASE_DEC,
 276                         NULL, 0, "Metric for this route", HFILL }},
 277
 278                 { &hf_rip_auth,
 279                         { "Authentication type", "rip.auth.type", FT_UINT16, BASE_DEC,
 280                         NULL, 0, "Type of authentication", HFILL }},
 281
 282                 { &hf_rip_auth_passwd,
 283                         { "Password", "rip.auth.passwd", FT_STRING, BASE_DEC,
 284                         NULL, 0, "Authentication password", HFILL }},
 285
 286                 { &hf_rip_route_tag,
 287                         { "Route Tag", "rip.route_tag", FT_UINT16, BASE_DEC,
 288                         NULL, 0, "Route Tag", HFILL }},
 289
 290         };
 291         static gint *ett[] = {
 292                 &ett_rip,
 293                 &ett_rip_vec,
 294         };
 295
 296         proto_rip = proto_register_protocol("Routing Information Protocol",
 297                                 "RIP", "rip");
 298         proto_register_field_array(proto_rip, hf, array_length(hf));
 299         proto_register_subtree_array(ett, array_length(ett));
 300 }
 301
 302 void
 303 proto_reg_handoff_rip(void)
 304 {
 305         dissector_handle_t rip_handle;
 306
 307         rip_handle = create_dissector_handle(dissect_rip, proto_rip);
 308         dissector_add("udp.port", UDP_PORT_RIP, rip_handle);
 309 }