epan/dissectors/packet-fefd.c

   1 /* packet-fefd.c
   2  * Routines for the disassembly of the "Far End Failure Detection"
   3  *
   4  * $Id$
   5  *
   6  * Wireshark - Network traffic analyzer
   7  * By Gerald Combs <gerald@wireshark.org>
   8  * Copyright 1998 Gerald Combs
   9  *
  10  * Copied from packet-udld.c
  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 #ifdef HAVE_CONFIG_H
  28 # include "config.h"
  29 #endif
  30
  31 #include <epan/packet.h>
  32 #include <epan/strutil.h>
  33
  34 #include <epan/oui.h>
  35 #include <epan/nlpid.h>
  36
  37
  38
  39 /* Offsets in TLV structure. */
  40 #define TLV_TYPE        0
  41 #define TLV_LENGTH      2
  42
  43 static int proto_fefd = -1;
  44 static int hf_fefd_version = -1;
  45 static int hf_fefd_opcode = -1;
  46 static int hf_fefd_flags = -1;
  47 static int hf_fefd_flags_rt = -1;
  48 static int hf_fefd_flags_rsy = -1;
  49 static int hf_fefd_checksum = -1;
  50 static int hf_fefd_tlvtype = -1;
  51 static int hf_fefd_tlvlength = -1;
  52
  53 static gint ett_fefd = -1;
  54 static gint ett_fefd_flags = -1;
  55 static gint ett_fefd_tlv = -1;
  56
  57 static dissector_handle_t data_handle;
  58
  59 #define TYPE_DEVICE_ID        0x0001
  60 #define TYPE_PORT_ID          0x0002
  61 #define TYPE_ECHO             0x0003
  62 #define TYPE_MESSAGE_INTERVAL 0x0004
  63 #define TYPE_TIMEOUT_INTERVAL 0x0005
  64 #define TYPE_DEVICE_NAME      0x0006
  65 #define TYPE_SEQUENCE_NUMBER  0x0007
  66
  67
  68 static const value_string type_vals[] = {
  69     { TYPE_DEVICE_ID,          "Device ID" },
  70     { TYPE_PORT_ID,            "Port ID" },
  71     { TYPE_ECHO,               "Echo" },
  72     { TYPE_MESSAGE_INTERVAL,   "Message interval" },
  73     { TYPE_TIMEOUT_INTERVAL,   "Timeout interval" },
  74     { TYPE_DEVICE_NAME,        "Device name" },
  75     { TYPE_SEQUENCE_NUMBER,    "Sequence number" },
  76     { 0,                       NULL }
  77 };
  78
  79 #define OPCODE_RESERVED       0x00
  80 #define OPCODE_PROBE          0x01
  81 #define OPCODE_ECHO           0x02
  82 #define OPCODE_FLUSH          0x03
  83
  84 static const value_string opcode_vals[] = {
  85     { OPCODE_RESERVED, "Reserved" },
  86     { OPCODE_PROBE,    "Probe" },
  87     { OPCODE_ECHO,     "Echo" },
  88     { OPCODE_FLUSH,    "Flush" },
  89     { 0,               NULL }
  90 };
  91
  92 static void
  93 dissect_fefd(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
  94 {
  95     proto_item *ti;
  96     proto_tree *fefd_tree = NULL;
  97     int offset = 0;
  98     guint16 type;
  99     guint16 length;
 100     proto_item *tlvi;
 101     proto_tree *tlv_tree;
 102     int real_length;
 103
 104     col_set_str(pinfo->cinfo, COL_PROTOCOL, "FEFD");
 105     col_clear(pinfo->cinfo, COL_INFO);
 106
 107     if (tree) {
 108         proto_item *flags_ti;
 109         proto_tree *flags_tree;
 110
 111         ti = proto_tree_add_item(tree, proto_fefd, tvb, offset, -1, FALSE);
 112         fefd_tree = proto_item_add_subtree(ti, ett_fefd);
 113
 114         /* FEFD header */
 115         proto_tree_add_item(fefd_tree, hf_fefd_version, tvb, offset, 1, FALSE);
 116         proto_tree_add_item(fefd_tree, hf_fefd_opcode, tvb, offset, 1, FALSE);
 117         offset += 1;
 118         flags_ti = proto_tree_add_item(fefd_tree, hf_fefd_flags, tvb, offset, 1, FALSE);
 119         flags_tree = proto_item_add_subtree(flags_ti, ett_fefd_flags);
 120         proto_tree_add_item(flags_tree, hf_fefd_flags_rt, tvb, offset, 1, FALSE);
 121         proto_tree_add_item(flags_tree, hf_fefd_flags_rsy, tvb, offset, 1, FALSE);
 122         offset += 1;
 123         proto_tree_add_item(fefd_tree, hf_fefd_checksum, tvb, offset, 2, FALSE);
 124         offset += 2;
 125     } else {
 126         offset += 4; /* The version/opcode/flags/checksum fields from above */
 127     }
 128
 129     while (tvb_reported_length_remaining(tvb, offset) != 0) {
 130         type = tvb_get_ntohs(tvb, offset + TLV_TYPE);
 131         length = tvb_get_ntohs(tvb, offset + TLV_LENGTH);
 132         if (length < 4) {
 133             if (tree) {
 134                 tlvi = proto_tree_add_text(fefd_tree, tvb, offset, 4,
 135                                            "TLV with invalid length %u (< 4)",
 136                                            length);
 137                 tlv_tree = proto_item_add_subtree(tlvi, ett_fefd_tlv);
 138                 proto_tree_add_uint(tlv_tree, hf_fefd_tlvtype, tvb,
 139                                     offset + TLV_TYPE, 2, type);
 140                 proto_tree_add_uint(tlv_tree, hf_fefd_tlvlength, tvb,
 141                                     offset + TLV_LENGTH, 2, length);
 142             }
 143             offset += 4;
 144             break;
 145         }
 146
 147         switch (type) {
 148
 149         case TYPE_DEVICE_ID:
 150             /* Device ID */
 151
 152             if (check_col(pinfo->cinfo, COL_INFO))
 153                 col_append_sep_fstr(pinfo->cinfo, COL_INFO, NULL,
 154                                     "Device ID: %s",
 155                                     tvb_format_stringzpad(tvb, offset + 4,
 156                                                           length - 4));
 157
 158             if (tree) {
 159                 tlvi = proto_tree_add_text(fefd_tree, tvb, offset,
 160                                            length, "Device ID: %s",
 161                                            tvb_format_stringzpad(tvb, offset + 4, length - 4));
 162                 tlv_tree = proto_item_add_subtree(tlvi, ett_fefd_tlv);
 163                 proto_tree_add_uint(tlv_tree, hf_fefd_tlvtype, tvb,
 164                                     offset + TLV_TYPE, 2, type);
 165                 proto_tree_add_uint(tlv_tree, hf_fefd_tlvlength, tvb,
 166                                     offset + TLV_LENGTH, 2, length);
 167                 proto_tree_add_text(tlv_tree, tvb, offset + 4,
 168                                     length - 4, "Device ID: %s",
 169                                     tvb_format_stringzpad(tvb, offset + 4, length - 4));
 170             }
 171             offset += length;
 172             break;
 173
 174         case TYPE_PORT_ID:
 175             real_length = length;
 176             if (tvb_get_guint8(tvb, offset + real_length) != 0x00) {
 177                 /* The length in the TLV doesn't appear to be the
 178                    length of the TLV, as the byte just past it
 179                    isn't the first byte of a 2-byte big-endian
 180                    small integer; make the length of the TLV the length
 181                    in the TLV, plus 4 bytes for the TLV type and length,
 182                    minus 1 because that's what makes one capture work. */
 183                 real_length = length + 3;
 184             }
 185
 186             if (check_col(pinfo->cinfo, COL_INFO))
 187                 col_append_sep_fstr(pinfo->cinfo, COL_INFO, NULL,
 188                                     "Port ID: %s",
 189                                     tvb_format_stringzpad(tvb, offset + 4, real_length - 4));
 190
 191             if (tree) {
 192                 tlvi = proto_tree_add_text(fefd_tree, tvb, offset,
 193                                            real_length, "Port ID: %s",
 194                                            tvb_format_text(tvb, offset + 4, real_length - 4));
 195                 tlv_tree = proto_item_add_subtree(tlvi, ett_fefd_tlv);
 196                 proto_tree_add_uint(tlv_tree, hf_fefd_tlvtype, tvb,
 197                                     offset + TLV_TYPE, 2, type);
 198                 proto_tree_add_uint(tlv_tree, hf_fefd_tlvlength, tvb,
 199                                     offset + TLV_LENGTH, 2, length);
 200                 proto_tree_add_text(tlv_tree, tvb, offset + 4,
 201                                     real_length - 4,
 202                                     "Sent through Interface: %s",
 203                                     tvb_format_text(tvb, offset + 4, real_length - 4));
 204             }
 205             offset += real_length;
 206             break;
 207
 208         case TYPE_ECHO:
 209         case TYPE_MESSAGE_INTERVAL:
 210         case TYPE_TIMEOUT_INTERVAL:
 211         case TYPE_DEVICE_NAME:
 212         case TYPE_SEQUENCE_NUMBER:
 213         default:
 214             tlvi = proto_tree_add_text(fefd_tree, tvb, offset,
 215                                        length, "Type: %s, length: %u",
 216                                        val_to_str(type, type_vals, "Unknown (0x%04x)"),
 217                                        length);
 218             tlv_tree = proto_item_add_subtree(tlvi, ett_fefd_tlv);
 219             proto_tree_add_uint(tlv_tree, hf_fefd_tlvtype, tvb,
 220                                 offset + TLV_TYPE, 2, type);
 221             proto_tree_add_uint(tlv_tree, hf_fefd_tlvlength, tvb,
 222                                 offset + TLV_LENGTH, 2, length);
 223             if (length > 4) {
 224                 proto_tree_add_text(tlv_tree, tvb, offset + 4,
 225                                     length - 4, "Data");
 226             } else {
 227                 return;
 228             }
 229             offset += length;
 230         }
 231     }
 232
 233     call_dissector(data_handle, tvb_new_subset_remaining(tvb, offset), pinfo, fefd_tree);
 234 }
 235
 236 void
 237 proto_register_fefd(void)
 238 {
 239     static hf_register_info hf[] = {
 240         { &hf_fefd_version,
 241           { "Version",          "fefd.version",  FT_UINT8, BASE_DEC, NULL, 0xE0,
 242             NULL, HFILL }},
 243
 244         { &hf_fefd_opcode,
 245           { "Opcode",           "fefd.opcode", FT_UINT8, BASE_DEC, VALS(opcode_vals), 0x1F,
 246             NULL, HFILL }},
 247
 248         { &hf_fefd_flags,
 249           { "Flags",            "fefd.flags", FT_UINT8, BASE_HEX, NULL, 0x0,
 250             NULL, HFILL }},
 251
 252         { &hf_fefd_flags_rt,
 253           { "Recommended timeout",              "fefd.flags.rt", FT_BOOLEAN, 8, NULL, 0x80,
 254             NULL, HFILL }},
 255
 256         { &hf_fefd_flags_rsy,
 257           { "ReSynch",          "fefd.flags.rsy", FT_BOOLEAN, 8, NULL, 0x40,
 258             NULL, HFILL }},
 259
 260         { &hf_fefd_checksum,
 261           { "Checksum",         "fefd.checksum", FT_UINT16, BASE_HEX, NULL, 0x0,
 262             NULL, HFILL }},
 263
 264         { &hf_fefd_tlvtype,
 265           { "Type",             "fefd.tlv.type", FT_UINT16, BASE_HEX, VALS(type_vals), 0x0,
 266             NULL, HFILL }},
 267
 268         { &hf_fefd_tlvlength,
 269           { "Length",           "fefd.tlv.len", FT_UINT16, BASE_DEC, NULL, 0x0,
 270             NULL, HFILL }}
 271     };
 272     static gint *ett[] = {
 273         &ett_fefd,
 274         &ett_fefd_flags,
 275         &ett_fefd_tlv
 276     };
 277
 278     proto_fefd = proto_register_protocol("Far End Failure Detection", "FEFD", "fefd");
 279     proto_register_field_array(proto_fefd, hf, array_length(hf));
 280     proto_register_subtree_array(ett, array_length(ett));
 281 }
 282
 283 void
 284 proto_reg_handoff_fefd(void)
 285 {
 286     dissector_handle_t fefd_handle;
 287
 288     data_handle = find_dissector("data");
 289     fefd_handle = create_dissector_handle(dissect_fefd, proto_fefd);
 290     dissector_add_uint("llc.force10_pid", 0x0111, fefd_handle);
 291 }