epan/dissectors/packet-mpls-y1711.c

   1 /* packet-mpls-y1711.c
   2  * Routines for (old) ITU-T MPLS OAM: it conforms to ITU-T Y.1711 and RFC 3429
   3  *
   4  * Copyright 2006, 2011 _FF_
   5  *
   6  * Francesco Fondelli <francesco dot fondelli, gmail dot com>
   7  *
   8  * $Id$
   9  *
  10  * Wireshark - Network traffic analyzer
  11  * By Gerald Combs <gerald@wireshark.org>
  12  * Copyright 1998 Gerald Combs
  13  *
  14  * This program is free software; you can redistribute it and/or
  15  * modify it under the terms of the GNU General Public License
  16  * as published by the Free Software Foundation; either version 2
  17  * of the License, or (at your option) any later version.
  18  *
  19  * This program is distributed in the hope that it will be useful,
  20  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  21  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  22  * GNU General Public License for more details.
  23  *
  24  * You should have received a copy of the GNU General Public License
  25  * along with this program; if not, write to the Free Software
  26  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  27  */
  28
  29 /*
  30  * FF: NOTES
  31  *
  32  * - this should dissect OAM pdus (identified by the MPLS_LABEL_OAM_ALERT = 14
  33  *   label) as described in ITU-T Y.1711 and RFC 3429.
  34  *
  35  * - this code used to be (since 2006) in packet-mpls.c ... nobody on this
  36  *   planet is using Y.1711 today (?), so thanks to the mpls subdissector
  37  *   table indexed by label value it has been moved here.
  38  */
  39
  40 #include "config.h"
  41
  42 #include <glib.h>
  43
  44 #include <epan/packet.h>
  45 #include <epan/addr_resolv.h>
  46 #include <epan/expert.h>
  47
  48 #include "packet-mpls.h"
  49
  50 static gint proto_mpls_y1711 = -1;
  51
  52 static int hf_mpls_y1711_function_type = -1;
  53 /* static int hf_mpls_y1711_ttsi = -1; */
  54 static int hf_mpls_y1711_frequency = -1;
  55 static int hf_mpls_y1711_defect_type = -1;
  56 static int hf_mpls_y1711_defect_location = -1;
  57 static int hf_mpls_y1711_bip16 = -1;
  58 /* Generated from convert_proto_tree_add_text.pl */
  59 static int hf_mpls_y1711_lsr_id = -1;
  60 static int hf_mpls_y1711_lsp_id = -1;
  61
  62 static gint ett_mpls_y1711 = -1;
  63
  64 /* Generated from convert_proto_tree_add_text.pl */
  65 static expert_field ei_mpls_y1711_padding_not_ff = EI_INIT;
  66 static expert_field ei_mpls_y1711_reserved_not_zero = EI_INIT;
  67 static expert_field ei_mpls_y1711_ttsi_not_preset = EI_INIT;
  68 static expert_field ei_mpls_y1711_minimum_payload = EI_INIT;
  69 static expert_field ei_mpls_y1711_s_bit_not_one = EI_INIT;
  70 static expert_field ei_mpls_y1711_no_OAM_alert_label = EI_INIT;
  71 static expert_field ei_mpls_y1711_exp_bits_not_zero = EI_INIT;
  72 static expert_field ei_mpls_y1711_ttl_not_one = EI_INIT;
  73 static expert_field ei_mpls_y1711_padding_not_zero = EI_INIT;
  74 static expert_field ei_mpls_y1711_unknown_pdu = EI_INIT;
  75
  76 static dissector_handle_t mpls_y1711_handle;
  77 static dissector_handle_t data_handle;
  78
  79 static const value_string y1711_function_type_vals[] = {
  80     {0x00, "Reserved"                               },
  81     {0x01, "CV (Connectivity Verification)"         },
  82     {0x02, "FDI (Forward Defect Indicator)"         },
  83     {0x03, "BDI (Backward Defect Indicator)"        },
  84     {0x04, "Reserved for Performance packets"       },
  85     {0x05, "Reserved for LB-Req (Loopback Request)" },
  86     {0x06, "Reserved for LB-Rsp (Loopback Response)"},
  87     {0x07, "FDD (Fast Failure Detection)"           },
  88     {0,    NULL                                     }
  89 };
  90
  91 static const value_string y1711_frequency_vals[] = {
  92     {0x00, "Reserved"             },
  93     {0x01, "10 ms"                },
  94     {0x02, "20 ms"                },
  95     {0x03, "50 ms (default value)"},
  96     {0x04, "100 ms"               },
  97     {0x05, "200 ms"               },
  98     {0x06, "500 ms"               },
  99     /* 7-255 Reserved */
 100     {0,    NULL                   }
 101 };
 102
 103 static const value_string y1711_defect_type_vals[] = {
 104     {0x0000, "Reserved"      },
 105     {0x0101, "dServer"       },
 106     {0x0102, "dPeerME"       },
 107     {0x0201, "dLOCV"         },
 108     {0x0202, "dTTSI_Mismatch"},
 109     {0x0203, "dTTSI_Mismerge"},
 110     {0x0204, "dExcess"       },
 111     {0x02FF, "dUnknown"      },
 112     {0xFFFF, "Reserved"      },
 113     {0,      NULL            }
 114 };
 115
 116 static int
 117 dissect_mpls_y1711(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data)
 118 {
 119     struct mplsinfo *mplsinfo        = (struct mplsinfo *)data;
 120     int              offset          = 0;
 121     proto_item      *ti;
 122     proto_tree      *mpls_y1711_tree;
 123     int              functype;
 124     tvbuff_t        *data_tvb;
 125
 126     static const guint8 allone[]  = { 0xff, 0xff };
 127     static const guint8 allzero[] = { 0x00, 0x00, 0x00, 0x00, 0x00,
 128                                       0x00, 0x00, 0x00, 0x00, 0x00,
 129                                       0x00, 0x00, 0x00, 0x00, 0x00,
 130                                       0x00, 0x00, 0x00, 0x00, 0x00 };
 131
 132     functype = tvb_get_guint8(tvb, offset);
 133     col_append_fstr(pinfo->cinfo, COL_INFO, " (Y.1711: %s)",
 134                     (functype == 0x01) ? "CV" :
 135                     (functype == 0x02) ? "FDI" :
 136                     (functype == 0x03) ? "BDI" :
 137                     (functype == 0x07) ? "FDD" :
 138                     "reserved/unknown");
 139
 140     /* sanity checks */
 141     if (tvb_reported_length(tvb) < 44) {
 142         /*
 143          * ITU-T Y.1711, 5.3: PDUs must have a minimum payload length of
 144          * 44 bytes
 145          */
 146         proto_tree_add_expert(tree, pinfo, &ei_mpls_y1711_minimum_payload, tvb, offset, -1);
 147         data_tvb = tvb_new_subset_remaining(tvb, offset);
 148         call_dissector(data_handle, data_tvb, pinfo, tree);
 149
 150         return tvb_reported_length(tvb);
 151     }
 152
 153     ti = proto_tree_add_text(tree, tvb, offset, 44, "Y.1711 OAM");
 154     mpls_y1711_tree = proto_item_add_subtree(ti, ett_mpls_y1711);
 155
 156     /* checks for exp, bos and ttl encoding */
 157     if (mplsinfo->label != MPLS_LABEL_OAM_ALERT)
 158         proto_tree_add_expert_format(mpls_y1711_tree, pinfo, &ei_mpls_y1711_no_OAM_alert_label, tvb, offset - 4, 3,
 159                                      "Warning: Y.1711 but no OAM alert label (%d) ?!", MPLS_LABEL_OAM_ALERT);
 160
 161     if (mplsinfo->exp != 0)
 162         proto_tree_add_expert(mpls_y1711_tree, pinfo, &ei_mpls_y1711_exp_bits_not_zero, tvb, offset - 2, 1);
 163
 164     if (mplsinfo->bos != 1)
 165         proto_tree_add_expert(mpls_y1711_tree, pinfo, &ei_mpls_y1711_s_bit_not_one, tvb, offset - 2, 1);
 166
 167     if (mplsinfo->ttl != 1)
 168         proto_tree_add_expert(mpls_y1711_tree, pinfo, &ei_mpls_y1711_ttl_not_one, tvb, offset - 1, 1);
 169
 170     /* starting dissection */
 171     functype = tvb_get_guint8(tvb, offset);
 172     proto_tree_add_item(mpls_y1711_tree, hf_mpls_y1711_function_type, tvb,
 173                         offset, 1,
 174                         ENC_LITTLE_ENDIAN);
 175     offset++;
 176
 177     switch (functype) {
 178     case 0x01: /* CV */
 179     {
 180         /* 3 octets reserved (all 0x00) */
 181         if (tvb_memeql(tvb, offset, allzero, 3) == -1) {
 182             proto_tree_add_expert(mpls_y1711_tree, pinfo, &ei_mpls_y1711_reserved_not_zero, tvb, offset, 3);
 183         }
 184         offset += 3;
 185
 186         /* ttsi (ipv4 flavor as in RFC 2373) */
 187         if (tvb_memeql(tvb, offset, allzero, 10) == -1) {
 188             proto_tree_add_expert(mpls_y1711_tree, pinfo, &ei_mpls_y1711_padding_not_zero, tvb, offset, 10);
 189         }
 190         offset += 10;
 191
 192         if (tvb_memeql(tvb, offset, allone, 2) == -1) {
 193             proto_tree_add_expert(mpls_y1711_tree, pinfo, &ei_mpls_y1711_padding_not_ff, tvb, offset, 2);
 194         }
 195         offset += 2;
 196
 197         proto_tree_add_item(mpls_y1711_tree, hf_mpls_y1711_lsr_id, tvb, offset, 4, ENC_BIG_ENDIAN);
 198         offset += 4;
 199
 200         proto_tree_add_item(mpls_y1711_tree, hf_mpls_y1711_lsp_id, tvb, offset, 4, ENC_BIG_ENDIAN);
 201         offset += 4;
 202
 203         /* 18 octets of padding (all 0x00) */
 204         if (tvb_memeql(tvb, offset, allzero, 18) == -1) {
 205             proto_tree_add_expert(mpls_y1711_tree, pinfo, &ei_mpls_y1711_padding_not_zero, tvb, offset, 18);
 206         }
 207         offset += 18;
 208     }
 209     break;
 210
 211     case 0x02: /* FDI */
 212     case 0x03: /* BDI */
 213     {
 214         /* 1 octets reserved (all 0x00) */
 215         if (tvb_memeql(tvb, offset, allzero, 1) == -1) {
 216             proto_tree_add_expert_format(mpls_y1711_tree, pinfo, &ei_mpls_y1711_reserved_not_zero, tvb, offset, 3,
 217                                          "Error: this byte is reserved and must be 0x00");
 218         }
 219         offset++;
 220
 221         proto_tree_add_item(mpls_y1711_tree, hf_mpls_y1711_defect_type, tvb,
 222                             offset, 2,
 223                             ENC_LITTLE_ENDIAN);
 224         offset += 2;
 225
 226         /*
 227          * ttsi (ipv4 flavor as in RFC 2373) is optional if not used must
 228          * be set to all 0x00
 229          */
 230         if (tvb_memeql(tvb, offset, allzero, 20) == 0) {
 231             proto_tree_add_expert(mpls_y1711_tree, pinfo, &ei_mpls_y1711_ttsi_not_preset, tvb, offset, 20);
 232             offset += 20;
 233         } else {
 234             if (tvb_memeql(tvb, offset, allzero, 10) == -1) {
 235                 proto_tree_add_expert(mpls_y1711_tree, pinfo, &ei_mpls_y1711_padding_not_zero, tvb, offset, 10);
 236             }
 237             offset += 10;
 238
 239             if (tvb_memeql(tvb, offset, allone, 2) == -1) {
 240                 proto_tree_add_expert(mpls_y1711_tree, pinfo, &ei_mpls_y1711_padding_not_ff, tvb, offset, 2);
 241             }
 242             offset += 2;
 243
 244             proto_tree_add_item(mpls_y1711_tree, hf_mpls_y1711_lsr_id, tvb, offset, 4, ENC_BIG_ENDIAN);
 245             offset += 4;
 246
 247             proto_tree_add_item(mpls_y1711_tree, hf_mpls_y1711_lsp_id, tvb, offset, 4, ENC_BIG_ENDIAN);
 248             offset += 4;
 249         }
 250
 251         /* defect location */
 252         proto_tree_add_item(mpls_y1711_tree, hf_mpls_y1711_defect_location, tvb,
 253                             offset, 4,
 254                             ENC_LITTLE_ENDIAN);
 255         offset += 4;
 256
 257         /* 14 octets of padding (all 0x00) */
 258         if (tvb_memeql(tvb, offset, allzero, 14) == -1) {
 259             proto_tree_add_expert(mpls_y1711_tree, pinfo, &ei_mpls_y1711_padding_not_zero, tvb, offset, 14);
 260         }
 261         offset += 14;
 262     }
 263     break;
 264
 265     case 0x07: /* FDD */
 266     {
 267         /* 3 octets reserved (all 0x00) */
 268         if (tvb_memeql(tvb, offset, allzero, 3) == -1) {
 269             proto_tree_add_expert(mpls_y1711_tree, pinfo, &ei_mpls_y1711_reserved_not_zero, tvb, offset, 3);
 270         }
 271         offset += 3;
 272
 273         /* ttsi (ipv4 flavor as in RFC 2373) */
 274         if (tvb_memeql(tvb, offset, allzero, 10) == -1) {
 275             proto_tree_add_expert(mpls_y1711_tree, pinfo, &ei_mpls_y1711_padding_not_zero, tvb, offset, 10);
 276         }
 277         offset += 10;
 278
 279         if (tvb_memeql(tvb, offset, allone, 2) == -1) {
 280             proto_tree_add_expert(mpls_y1711_tree, pinfo, &ei_mpls_y1711_padding_not_ff, tvb, offset, 2);
 281         }
 282         offset += 2;
 283
 284         proto_tree_add_item(mpls_y1711_tree, hf_mpls_y1711_lsr_id, tvb, offset, 4, ENC_BIG_ENDIAN);
 285         offset += 4;
 286
 287         proto_tree_add_item(mpls_y1711_tree, hf_mpls_y1711_lsp_id, tvb, offset, 4, ENC_BIG_ENDIAN);
 288         offset += 4;
 289
 290         proto_tree_add_item(mpls_y1711_tree, hf_mpls_y1711_frequency, tvb,
 291                             offset, 1,
 292                             ENC_LITTLE_ENDIAN);
 293         offset++;
 294
 295         /* 17 octets of padding (all 0x00) */
 296         if (tvb_memeql(tvb, offset, allzero, 17) == -1) {
 297             proto_tree_add_expert(mpls_y1711_tree, pinfo, &ei_mpls_y1711_padding_not_zero, tvb, offset, 17);
 298         }
 299         offset += 17;
 300     }
 301     break;
 302
 303     default:
 304         proto_tree_add_expert(mpls_y1711_tree, pinfo, &ei_mpls_y1711_unknown_pdu, tvb, offset - 1, -1);
 305         return offset;
 306     }
 307
 308     /* BIP16 */
 309     proto_tree_add_item(mpls_y1711_tree, hf_mpls_y1711_bip16, tvb, offset, 2,
 310                         ENC_LITTLE_ENDIAN);
 311     offset += 2;
 312
 313     return offset;
 314 }
 315
 316 void
 317 proto_register_mpls_y1711(void)
 318 {
 319     static hf_register_info hf[] = {
 320         {
 321             &hf_mpls_y1711_function_type,
 322             {
 323                 "Function Type", "mpls_y1711.function_type", FT_UINT8,
 324                 BASE_HEX, VALS(y1711_function_type_vals),
 325                 0x0, "Function Type codepoint", HFILL
 326             }
 327         },
 328 #if 0
 329         {
 330             &hf_mpls_y1711_ttsi,
 331             {
 332                 "Trail Termination Source Identifier",
 333                 "mpls_y1711.ttsi",
 334                 FT_UINT32, BASE_HEX, NULL, 0x0, NULL, HFILL
 335             }
 336         },
 337 #endif
 338         {
 339             &hf_mpls_y1711_frequency,
 340             {
 341                 "Frequency", "mpls_y1711.frequency", FT_UINT8,
 342                 BASE_HEX, VALS(y1711_frequency_vals), 0x0,
 343                 "Frequency of probe injection", HFILL
 344             }
 345         },
 346         {
 347             &hf_mpls_y1711_defect_type,
 348             {
 349                 "Defect Type", "mpls_y1711.defect_type", FT_UINT16,
 350                 BASE_HEX, VALS(y1711_defect_type_vals), 0x0, NULL, HFILL
 351             }
 352         },
 353         {
 354             &hf_mpls_y1711_defect_location,
 355             {
 356                 "Defect Location (AS)", "mpls_y1711.defect_location",
 357                 FT_UINT32, BASE_DEC, NULL, 0x0, "Defect Location", HFILL
 358             }
 359         },
 360         {
 361             &hf_mpls_y1711_bip16,
 362             {
 363                 "BIP16", "mpls_y1711.bip16", FT_UINT16,
 364                 BASE_HEX, NULL, 0x0, NULL, HFILL
 365             }
 366         },
 367       /* Generated from convert_proto_tree_add_text.pl */
 368       { &hf_mpls_y1711_lsr_id, { "LSR ID", "mpls_y1711.lsr_id", FT_IPv4, BASE_NONE, NULL, 0x0, NULL, HFILL }},
 369       { &hf_mpls_y1711_lsp_id, { "LSP ID", "mpls_y1711.lsp_id", FT_INT32, BASE_DEC, NULL, 0x0, NULL, HFILL }},
 370     };
 371
 372     static gint *ett[] = {
 373         &ett_mpls_y1711
 374     };
 375
 376     static ei_register_info ei[] = {
 377         /* Generated from convert_proto_tree_add_text.pl */
 378         { &ei_mpls_y1711_minimum_payload, { "mpls_y1711.minimum_payload", PI_MALFORMED, PI_ERROR, "Error: must have a minimum payload length of 44 bytes", EXPFILL }},
 379         { &ei_mpls_y1711_no_OAM_alert_label, { "mpls_y1711.no_OAM_alert_label", PI_PROTOCOL, PI_WARN, "Warning: Y.1711 but no OAM alert label (%d) ?!", EXPFILL }},
 380         { &ei_mpls_y1711_exp_bits_not_zero, { "mpls_y1711.exp_bits_not_0", PI_PROTOCOL, PI_WARN, "Warning: Exp bits should be 0 for Y.1711", EXPFILL }},
 381         { &ei_mpls_y1711_s_bit_not_one, { "mpls_y1711.s_bit_not_1", PI_PROTOCOL, PI_WARN, "Warning: S bit should be 1 for Y.1711", EXPFILL }},
 382         { &ei_mpls_y1711_ttl_not_one, { "mpls_y1711.ttl_not_1", PI_PROTOCOL, PI_WARN, "Warning: TTL should be 1 for Y.1711", EXPFILL }},
 383         { &ei_mpls_y1711_reserved_not_zero, { "mpls_y1711.reserved_not_zero", PI_PROTOCOL, PI_WARN, "Error: these bytes are reserved and must be 0x00", EXPFILL }},
 384         { &ei_mpls_y1711_padding_not_zero, { "mpls_y1711.padding_not_zero", PI_PROTOCOL, PI_WARN, "Error: these bytes are padding and must be 0x00", EXPFILL }},
 385         { &ei_mpls_y1711_padding_not_ff, { "mpls_y1711.padding_not_ff", PI_PROTOCOL, PI_WARN, "Error: these bytes are padding and must be 0xFF", EXPFILL }},
 386         { &ei_mpls_y1711_ttsi_not_preset, { "mpls_y1711.ttsi_not_preset", PI_PROTOCOL, PI_NOTE, "TTSI not preset (optional for FDI/BDI)", EXPFILL }},
 387         { &ei_mpls_y1711_unknown_pdu, { "mpls_y1711.unknown_pdu", PI_PROTOCOL, PI_WARN, "Unknown MPLS Y.1711 PDU", EXPFILL }},
 388     };
 389
 390     expert_module_t* expert_mpls_y1711;
 391
 392     proto_mpls_y1711 =
 393         proto_register_protocol("MPLS ITU-T Y.1711 OAM",
 394                                 "MPLS ITU-T Y.1711 OAM",
 395                                 "mpls_y1711");
 396     proto_register_field_array(proto_mpls_y1711, hf, array_length(hf));
 397     proto_register_subtree_array(ett, array_length(ett));
 398     expert_mpls_y1711 = expert_register_protocol(proto_mpls_y1711);
 399     expert_register_field_array(expert_mpls_y1711, ei, array_length(ei));
 400     new_register_dissector("mpls_y1711", dissect_mpls_y1711, proto_mpls_y1711);
 401 }
 402
 403 void
 404 proto_reg_handoff_mpls_y1711(void)
 405 {
 406     mpls_y1711_handle = find_dissector("mpls_y1711");
 407     dissector_add_uint("mpls.label",
 408                        MPLS_LABEL_OAM_ALERT /* 14 */,
 409                        mpls_y1711_handle);
 410
 411     data_handle = find_dissector("data");
 412 }
 413
 414 /*
 415  * Editor modelines  -  http://www.wireshark.org/tools/modelines.html
 416  *
 417  * Local variables:
 418  * c-basic-offset: 4
 419  * tab-width: 8
 420  * indent-tabs-mode: nil
 421  * End:
 422  *
 423  * vi: set shiftwidth=4 tabstop=8 expandtab:
 424  * :indentSize=4:tabSize=8:noTabs=true:
 425  */