packet-rip.c

   1 /* packet-rip.c
   2  * Routines for RIPv1 and RIPv2 packet disassembly
   3  * (c) Copyright Hannes R. Boehm <hannes@boehm.org>
   4  *
   5  * $Id: packet-rip.c,v 1.30 2002/01/24 09:20:51 guy Exp $
   6  *
   7  * Ethereal - Network traffic analyzer
   8  * By Gerald Combs <gerald@ethereal.com>
   9  * Copyright 1998 Gerald Combs
  10  *
  11  * This program is free software; you can redistribute it and/or
  12  * modify it under the terms of the GNU General Public License
  13  * as published by the Free Software Foundation; either version 2
  14  * of the License, or (at your option) any later version.
  15  *
  16  * This program is distributed in the hope that it will be useful,
  17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19  * GNU General Public License for more details.
  20  *
  21  * You should have received a copy of the GNU General Public License
  22  * along with this program; if not, write to the Free Software
  23  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  24  */
  25
  26 #include "config.h"
  27
  28 #ifdef HAVE_SYS_TYPES_H
  29 #include <sys/types.h>
  30 #endif
  31
  32 #ifdef HAVE_NETINET_IN_H
  33 #include <netinet/in.h>
  34 #endif
  35
  36 #include <string.h>
  37 #include <glib.h>
  38 #include <epan/packet.h>
  39
  40 #define UDP_PORT_RIP    520
  41
  42 #define RIPv1   1
  43 #define RIPv2   2
  44
  45 static const value_string version_vals[] = {
  46         { RIPv1, "RIPv1" },
  47         { RIPv2, "RIPv2" },
  48         { 0,     NULL }
  49 };
  50
  51 static const value_string command_vals[] = {
  52         { 1, "Request" },
  53         { 2, "Response" },
  54         { 3, "Traceon" },
  55         { 4, "Traceoff" },
  56         { 5, "Vendor specific (Sun)" },
  57         { 0, NULL }
  58 };
  59
  60 static const value_string family_vals[] = {
  61         { 2,    "IP" },
  62         { 0,    NULL }
  63 };
  64
  65 #define RIP_HEADER_LENGTH 4
  66 #define RIP_ENTRY_LENGTH 20
  67
  68 static int proto_rip = -1;
  69 static int hf_rip_command = -1;
  70 static int hf_rip_version = -1;
  71 static int hf_rip_routing_domain = -1;
  72 static int hf_rip_ip = -1;
  73 static int hf_rip_netmask = -1;
  74 static int hf_rip_next_hop = -1;
  75 static int hf_rip_metric = -1;
  76 static int hf_rip_auth = -1;
  77 static int hf_rip_auth_passwd = -1;
  78 static int hf_rip_family = -1;
  79 static int hf_rip_route_tag = -1;
  80
  81 static gint ett_rip = -1;
  82 static gint ett_rip_vec = -1;
  83
  84 static void dissect_ip_rip_vektor(tvbuff_t *tvb, int offset, guint8 version,
  85     proto_tree *tree);
  86 static void dissect_rip_authentication(tvbuff_t *tvb, int offset,
  87     proto_tree *tree);
  88
  89 static void
  90 dissect_rip(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
  91 {
  92     int offset = 0;
  93     proto_tree *rip_tree = NULL;
  94     proto_item *ti;
  95     guint8 command;
  96     guint8 version;
  97     guint16 family;
  98
  99     if (check_col(pinfo->cinfo, COL_PROTOCOL))
 100         col_set_str(pinfo->cinfo, COL_PROTOCOL, "RIP");
 101     if (check_col(pinfo->cinfo, COL_INFO))
 102         col_clear(pinfo->cinfo, COL_INFO);
 103
 104     command = tvb_get_guint8(tvb, 0);
 105     version = tvb_get_guint8(tvb, 1);
 106
 107     if (check_col(pinfo->cinfo, COL_PROTOCOL))
 108         col_add_str(pinfo->cinfo, COL_PROTOCOL,
 109                     val_to_str(version, version_vals, "RIP"));
 110     if (check_col(pinfo->cinfo, COL_INFO))
 111         col_add_str(pinfo->cinfo, COL_INFO,
 112                     val_to_str(command, command_vals, "Unknown command (%u)"));
 113
 114     if (tree) {
 115         ti = proto_tree_add_item(tree, proto_rip, tvb, 0, -1, FALSE);
 116         rip_tree = proto_item_add_subtree(ti, ett_rip);
 117
 118         proto_tree_add_uint(rip_tree, hf_rip_command, tvb, 0, 1, command);
 119         proto_tree_add_uint(rip_tree, hf_rip_version, tvb, 1, 1, version);
 120         if (version == RIPv2)
 121             proto_tree_add_uint(rip_tree, hf_rip_routing_domain, tvb, 2, 2,
 122                         tvb_get_ntohs(tvb, 2));
 123
 124         /* skip header */
 125         offset = RIP_HEADER_LENGTH;
 126
 127         /* zero or more entries */
 128         while (tvb_reported_length_remaining(tvb, offset) > 0) {
 129             family = tvb_get_ntohs(tvb, offset);
 130             switch (family) {
 131             case 2: /* IP */
 132                 dissect_ip_rip_vektor(tvb, offset, version, rip_tree);
 133                 break;
 134             case 0xFFFF:
 135                 dissect_rip_authentication(tvb, offset, rip_tree);
 136                 break;
 137             default:
 138                 proto_tree_add_text(rip_tree, tvb, offset,
 139                                 RIP_ENTRY_LENGTH, "Unknown address family %u",
 140                                 family);
 141                 break;
 142             }
 143
 144             offset += RIP_ENTRY_LENGTH;
 145         }
 146     }
 147 }
 148
 149 static void
 150 dissect_ip_rip_vektor(tvbuff_t *tvb, int offset, guint8 version,
 151                       proto_tree *tree)
 152 {
 153     proto_item *ti;
 154     proto_tree *rip_vektor_tree;
 155     guint32 metric;
 156
 157     metric = tvb_get_ntohl(tvb, offset+16);
 158     ti = proto_tree_add_text(tree, tvb, offset,
 159                              RIP_ENTRY_LENGTH, "IP Address: %s, Metric: %u",
 160                              ip_to_str(tvb_get_ptr(tvb, offset+4, 4)), metric);
 161     rip_vektor_tree = proto_item_add_subtree(ti, ett_rip_vec);
 162
 163
 164     proto_tree_add_uint(rip_vektor_tree, hf_rip_family, tvb, offset, 2,
 165                         tvb_get_ntohs(tvb, offset));
 166     if (version == RIPv2) {
 167         proto_tree_add_uint(rip_vektor_tree, hf_rip_route_tag, tvb, offset+2, 2,
 168                         tvb_get_ntohs(tvb, offset+2));
 169     }
 170
 171     proto_tree_add_item(rip_vektor_tree, hf_rip_ip, tvb, offset+4, 4, FALSE);
 172
 173     if (version == RIPv2) {
 174         proto_tree_add_item(rip_vektor_tree, hf_rip_netmask, tvb, offset+8, 4,
 175                             FALSE);
 176         proto_tree_add_item(rip_vektor_tree, hf_rip_next_hop, tvb, offset+12, 4,
 177                             FALSE);
 178     }
 179     proto_tree_add_uint(rip_vektor_tree, hf_rip_metric, tvb,
 180                         offset+16, 4, metric);
 181 }
 182
 183 static void
 184 dissect_rip_authentication(tvbuff_t *tvb, int offset, proto_tree *tree)
 185 {
 186     proto_item *ti;
 187     proto_tree *rip_authentication_tree;
 188     guint16 authtype;
 189
 190     ti = proto_tree_add_text(tree, tvb, offset, RIP_ENTRY_LENGTH,
 191                              "Authentication");
 192     rip_authentication_tree = proto_item_add_subtree(ti, ett_rip_vec);
 193
 194     authtype = tvb_get_ntohs(tvb, offset + 2);
 195     proto_tree_add_uint(rip_authentication_tree, hf_rip_auth, tvb, offset+2, 2,
 196                 authtype);
 197     if (authtype == 2) {
 198         proto_tree_add_item(rip_authentication_tree, hf_rip_auth_passwd,
 199                         tvb, offset+4, 16, TRUE);
 200     }
 201 }
 202
 203 void
 204 proto_register_rip(void)
 205 {
 206         static hf_register_info hf[] = {
 207                 { &hf_rip_command,
 208                         { "Command", "rip.command", FT_UINT8, BASE_DEC,
 209                         VALS(command_vals), 0, "What type of RIP Command is this", HFILL }},
 210
 211                 { &hf_rip_version,
 212                         { "Version", "rip.version", FT_UINT8, BASE_DEC,
 213                         VALS(version_vals), 0, "Version of the RIP protocol", HFILL }},
 214
 215                 { &hf_rip_family,
 216                         { "Address Family", "rip.family", FT_UINT16, BASE_DEC,
 217                         VALS(family_vals), 0, "Address family", HFILL }},
 218
 219                 { &hf_rip_routing_domain,
 220                         { "Routing Domain", "rip.routing_domain", FT_UINT16, BASE_DEC,
 221                         NULL, 0, "RIPv2 Routing Domain", HFILL }},
 222
 223                 { &hf_rip_ip,
 224                         { "IP Address", "rip.ip", FT_IPv4, BASE_NONE,
 225                         NULL, 0, "IP Address", HFILL}},
 226
 227                 { &hf_rip_netmask,
 228                         { "Netmask", "rip.netmask", FT_IPv4, BASE_NONE,
 229                         NULL, 0, "Netmask", HFILL}},
 230
 231                 { &hf_rip_next_hop,
 232                         { "Next Hop", "rip.next_hop", FT_IPv4, BASE_NONE,
 233                         NULL, 0, "Next Hop router for this route", HFILL}},
 234
 235                 { &hf_rip_metric,
 236                         { "Metric", "rip.metric", FT_UINT16, BASE_DEC,
 237                         NULL, 0, "Metric for this route", HFILL }},
 238
 239                 { &hf_rip_auth,
 240                         { "Authentication type", "rip.auth.type", FT_UINT16, BASE_DEC,
 241                         NULL, 0, "Type of authentication", HFILL }},
 242
 243                 { &hf_rip_auth_passwd,
 244                         { "Password", "rip.auth.passwd", FT_STRING, BASE_DEC,
 245                         NULL, 0, "Authentication password", HFILL }},
 246
 247                 { &hf_rip_route_tag,
 248                         { "Route Tag", "rip.route_tag", FT_UINT16, BASE_DEC,
 249                         NULL, 0, "Route Tag", HFILL }},
 250
 251         };
 252         static gint *ett[] = {
 253                 &ett_rip,
 254                 &ett_rip_vec,
 255         };
 256
 257         proto_rip = proto_register_protocol("Routing Information Protocol",
 258                                 "RIP", "rip");
 259         proto_register_field_array(proto_rip, hf, array_length(hf));
 260         proto_register_subtree_array(ett, array_length(ett));
 261 }
 262
 263 void
 264 proto_reg_handoff_rip(void)
 265 {
 266         dissector_handle_t rip_handle;
 267
 268         rip_handle = create_dissector_handle(dissect_rip, proto_rip);
 269         dissector_add("udp.port", UDP_PORT_RIP, rip_handle);
 270 }