epan/dissectors/packet-geneve.c

   1 /* packet-geneve.c
   2  * Routines for Geneve - Generic Network Virtualization Encapsulation
   3  * http://tools.ietf.org/html/draft-ietf-nvo3-geneve
   4  *
   5  * Copyright (c) 2014 VMware, Inc. All Rights Reserved.
   6  * Author: Jesse Gross <jesse@nicira.com>
   7  *
   8  * Wireshark - Network traffic analyzer
   9  * By Gerald Combs <gerald@wireshark.org>
  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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  25  */
  26
  27
  28 #include "config.h"
  29
  30 #include <epan/packet.h>
  31 #include <epan/etypes.h>
  32 #include <epan/expert.h>
  33
  34 #define UDP_PORT_GENEVE  6081
  35 #define GENEVE_VER 0
  36
  37 #define VER_SHIFT 6
  38 #define HDR_OPTS_LEN_MASK 0x3F
  39
  40 #define FLAG_OAM (1 << 7)
  41
  42 #define OPT_TYPE_CRITICAL (1 << 7)
  43 #define OPT_FLAGS_SHIFT 5
  44 #define OPT_LEN_MASK 0x1F
  45
  46 static const range_string class_id_names[] = {
  47     { 0, 0xFF, "Standard" },
  48     { 0x0100, 0x0100, "Linux" },
  49     { 0x0101, 0x0101, "Open vSwitch" },
  50     { 0x0102, 0x0102, "Open Virtual Networking (OVN)" },
  51     { 0x0103, 0x0103, "In-band Network Telemetry (INT)" },
  52     { 0x0104, 0x0104, "VMware" },
  53     { 0xFFF0, 0xFFFF, "Experimental" },
  54     { 0, 0, NULL }
  55 };
  56
  57 void proto_register_geneve(void);
  58 void proto_reg_handoff_geneve(void);
  59
  60 static int proto_geneve = -1;
  61
  62 static int hf_geneve_version = -1;
  63 static int hf_geneve_opt_len = -1;
  64 static int hf_geneve_flags = -1;
  65 static int hf_geneve_flag_oam = -1;
  66 static int hf_geneve_flag_critical = -1;
  67 static int hf_geneve_flag_reserved = -1;
  68 static int hf_geneve_proto_type = -1;
  69 static int hf_geneve_vni = -1;
  70 static int hf_geneve_reserved = -1;
  71 static int hf_geneve_options = -1;
  72 static int hf_geneve_option_class = -1;
  73 static int hf_geneve_option_type = -1;
  74 static int hf_geneve_option_type_critical = -1;
  75 static int hf_geneve_option_flags = -1;
  76 static int hf_geneve_option_flags_reserved = -1;
  77 static int hf_geneve_option_length = -1;
  78 static int hf_geneve_opt_unknown = -1;
  79 static int hf_geneve_opt_unknown_data = -1;
  80
  81 static int ett_geneve = -1;
  82 static int ett_geneve_flags = -1;
  83 static int ett_geneve_opt_flags = -1;
  84 static int ett_geneve_options = -1;
  85 static int ett_geneve_unknown_opt = -1;
  86
  87 static expert_field ei_geneve_ver_unknown = EI_INIT;
  88 static expert_field ei_geneve_opt_len_invalid = EI_INIT;
  89
  90 static dissector_table_t ethertype_dissector_table;
  91
  92 static void
  93 print_flags(guint8 flags, proto_item *flag_item)
  94 {
  95     static const char flag_names[][5] = {"OAM", "CRIT"};
  96     unsigned int i;
  97
  98     if (!flags) {
  99         return;
 100     }
 101
 102     proto_item_append_text(flag_item, " (");
 103
 104     for (i = 0; i < array_length(flag_names); i++) {
 105         guint8 bit = 1 << (7 - i);
 106
 107         if (flags & bit) {
 108             proto_item_append_text(flag_item, "%s", flag_names[i]);
 109             flags &= ~bit;
 110
 111             if (flags) {
 112                 proto_item_append_text(flag_item, ", ");
 113             }
 114         }
 115     }
 116
 117     if (flags) {
 118         proto_item_append_text(flag_item, "RSVD");
 119     }
 120
 121     proto_item_append_text(flag_item, ")");
 122 }
 123
 124 static const char *
 125 format_unknown_option_name(guint16 opt_class, guint8 opt_type)
 126 {
 127     const char *name;
 128
 129     name = wmem_strdup_printf(wmem_packet_scope(),
 130                               "Unknown, Class: %s (0x%04x) Type: 0x%02x",
 131                               rval_to_str_const(opt_class, class_id_names, "Unknown"),
 132                               opt_class, opt_type);
 133
 134     return name;
 135 }
 136
 137 static void
 138 dissect_unknown_option(tvbuff_t *tvb, proto_tree *opts_tree, int offset,
 139                        guint16 opt_class, guint8 opt_type, int len)
 140 {
 141     proto_item *opt_item, *type_item, *hidden_item, *flag_item;
 142     proto_tree *opt_tree, *flag_tree;
 143     const char *critical;
 144     guint8 flags;
 145
 146     critical = opt_type & OPT_TYPE_CRITICAL ? "Critical" : "Non-critical";
 147
 148     opt_item = proto_tree_add_item(opts_tree, hf_geneve_opt_unknown,
 149                                    tvb, offset, len, ENC_NA);
 150     proto_item_set_text(opt_item, "%s (%s)",
 151                         format_unknown_option_name(opt_class, opt_type),
 152                         critical);
 153
 154     opt_tree = proto_item_add_subtree(opt_item, ett_geneve_unknown_opt);
 155
 156     proto_tree_add_item(opt_tree, hf_geneve_option_class, tvb,
 157                         offset, 2, ENC_BIG_ENDIAN);
 158     offset += 2;
 159
 160     type_item = proto_tree_add_item(opt_tree, hf_geneve_option_type, tvb,
 161                                     offset, 1, ENC_BIG_ENDIAN);
 162     proto_item_append_text(type_item, " (%s)", critical);
 163     hidden_item = proto_tree_add_item(opt_tree, hf_geneve_option_type_critical,
 164                                       tvb, offset, 1, ENC_BIG_ENDIAN);
 165     PROTO_ITEM_SET_HIDDEN(hidden_item);
 166     offset += 1;
 167
 168     flags = tvb_get_guint8(tvb, offset) >> OPT_FLAGS_SHIFT;
 169     flag_item = proto_tree_add_uint(opt_tree, hf_geneve_option_flags, tvb,
 170                                     offset, 1, flags);
 171     flag_tree = proto_item_add_subtree(flag_item, ett_geneve_opt_flags);
 172     proto_tree_add_item(flag_tree, hf_geneve_option_flags_reserved, tvb,
 173                         offset, 1, ENC_BIG_ENDIAN);
 174     if (flags) {
 175         proto_item_append_text(flag_item, " (RSVD)");
 176     } else {
 177         PROTO_ITEM_SET_HIDDEN(flag_item);
 178     }
 179
 180     proto_tree_add_uint_format_value(opt_tree, hf_geneve_option_length, tvb,
 181                                      offset, 1, len, "%u bytes", len);
 182     offset += 1;
 183
 184     proto_tree_add_item(opt_tree, hf_geneve_opt_unknown_data, tvb, offset,
 185                         len - 4, ENC_NA);
 186 }
 187
 188 static void
 189 dissect_geneve_options(tvbuff_t *tvb, packet_info *pinfo,
 190                        proto_tree *geneve_tree, int offset, int len)
 191 {
 192     proto_item *opts_item;
 193     proto_tree *opts_tree;
 194     guint16 opt_class;
 195     guint8 opt_type;
 196     guint8 opt_len;
 197
 198     opts_item = proto_tree_add_item(geneve_tree, hf_geneve_options, tvb,
 199                                     offset, len, ENC_NA);
 200     proto_item_set_text(opts_item, "Options: (%u bytes)", len);
 201     opts_tree = proto_item_add_subtree(opts_item, ett_geneve_options);
 202
 203     while (len > 0) {
 204         opt_class = tvb_get_ntohs(tvb, offset);
 205         opt_type = tvb_get_guint8(tvb, offset + 2);
 206         opt_len = 4 + ((tvb_get_guint8(tvb, offset + 3) & OPT_LEN_MASK) * 4);
 207
 208         if (opt_len > len) {
 209             proto_tree_add_expert_format(opts_tree, pinfo,
 210                                          &ei_geneve_opt_len_invalid, tvb,
 211                                          offset + 3, 1,
 212                                          "%s (length of %u is past end of options)",
 213                                          format_unknown_option_name(opt_class,
 214                                                                     opt_type),
 215                                          opt_len);
 216             return;
 217         }
 218
 219         dissect_unknown_option(tvb, opts_tree, offset,
 220                                opt_class, opt_type, opt_len);
 221
 222         offset += opt_len;
 223         len -= opt_len;
 224     };
 225 }
 226
 227 static int
 228 dissect_geneve(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_)
 229 {
 230     proto_item *ti, *flag_item, *rsvd_item;
 231     proto_tree *geneve_tree, *flag_tree;
 232     tvbuff_t *next_tvb;
 233     int offset = 0;
 234     guint8 ver_opt;
 235     guint8 ver;
 236     guint8 flags;
 237     guint16 proto_type;
 238     int opts_len;
 239
 240     col_set_str(pinfo->cinfo, COL_PROTOCOL, "Geneve");
 241     col_clear(pinfo->cinfo, COL_INFO);
 242
 243     ti = proto_tree_add_item(tree, proto_geneve, tvb, offset, -1, ENC_NA);
 244     geneve_tree = proto_item_add_subtree(ti, ett_geneve);
 245
 246     /* Version. */
 247     ver_opt = tvb_get_guint8(tvb, offset);
 248     ver = ver_opt >> VER_SHIFT;
 249     proto_tree_add_uint(geneve_tree, hf_geneve_version, tvb,
 250                         offset, 1, ver);
 251
 252     if (ver != GENEVE_VER) {
 253         proto_tree_add_expert_format(geneve_tree, pinfo,
 254                                      &ei_geneve_ver_unknown, tvb, offset, 1,
 255                                      "Unknown version %u", ver);
 256         col_add_fstr(pinfo->cinfo, COL_INFO, "Unknown Geneve version %u", ver);
 257     }
 258
 259     /* Option length. */
 260     opts_len = (ver_opt & HDR_OPTS_LEN_MASK) * 4;
 261     proto_tree_add_uint_format_value(geneve_tree, hf_geneve_opt_len, tvb,
 262                                      offset, 1, opts_len, "%u bytes", opts_len);
 263     offset += 1;
 264
 265     /* Flags. */
 266     flags = tvb_get_guint8(tvb, offset);
 267     if (tree) {
 268         flag_item = proto_tree_add_item(geneve_tree, hf_geneve_flags, tvb,
 269                                        offset, 1, ENC_BIG_ENDIAN);
 270         print_flags(flags, flag_item);
 271
 272         flag_tree = proto_item_add_subtree(flag_item, ett_geneve_flags);
 273
 274         proto_tree_add_item(flag_tree, hf_geneve_flag_oam, tvb, offset,
 275                             1, ENC_BIG_ENDIAN);
 276         proto_tree_add_item(flag_tree, hf_geneve_flag_critical, tvb, offset,
 277                             1, ENC_BIG_ENDIAN);
 278         proto_tree_add_item(flag_tree, hf_geneve_flag_reserved, tvb, offset,
 279                             1, ENC_BIG_ENDIAN);
 280     }
 281     offset += 1;
 282
 283     /* Protocol Type. */
 284     proto_tree_add_item(geneve_tree, hf_geneve_proto_type, tvb,
 285                         offset, 2, ENC_BIG_ENDIAN);
 286
 287     proto_type = tvb_get_ntohs(tvb, offset);
 288     col_add_fstr(pinfo->cinfo, COL_INFO, "Encapsulated %s",
 289                  val_to_str(proto_type, etype_vals, "0x%04x (unknown)"));
 290
 291     offset += 2;
 292
 293     /* VNI. */
 294     proto_tree_add_item(geneve_tree, hf_geneve_vni, tvb, offset, 3,
 295                         ENC_BIG_ENDIAN);
 296     proto_item_append_text(ti, ", VNI: 0x%06x%s", tvb_get_ntoh24(tvb, offset),
 297                            flags & FLAG_OAM ? ", OAM" : "");
 298     offset += 3;
 299
 300     /* Reserved. */
 301     rsvd_item = proto_tree_add_item(geneve_tree, hf_geneve_reserved, tvb,
 302                                     offset, 1, ENC_BIG_ENDIAN);
 303     if (!tvb_get_guint8(tvb, offset)) {
 304         PROTO_ITEM_SET_HIDDEN(rsvd_item);
 305     }
 306     offset += 1;
 307
 308     /* Options. */
 309     if (tree && opts_len) {
 310         dissect_geneve_options(tvb, pinfo, geneve_tree, offset, opts_len);
 311     }
 312     offset += opts_len;
 313
 314     proto_item_set_len(ti, offset);
 315
 316     next_tvb = tvb_new_subset_remaining(tvb, offset);
 317     if (!dissector_try_uint(ethertype_dissector_table, proto_type, next_tvb, pinfo, tree))
 318         call_data_dissector(next_tvb, pinfo, tree);
 319
 320     return tvb_captured_length(tvb);
 321 }
 322
 323 /* Register Geneve with Wireshark */
 324 void
 325 proto_register_geneve(void)
 326 {
 327     static hf_register_info hf[] = {
 328         { &hf_geneve_version,
 329           { "Version", "geneve.version",
 330             FT_UINT8, BASE_DEC, NULL, 0x00,
 331             NULL, HFILL }
 332         },
 333         { &hf_geneve_opt_len,
 334           { "Options Length", "geneve.options_length",
 335             FT_UINT8, BASE_DEC, NULL, 0x0,
 336             NULL, HFILL }
 337         },
 338         { &hf_geneve_flags,
 339           { "Flags", "geneve.flags",
 340             FT_UINT8, BASE_HEX, NULL, 0x00,
 341             NULL, HFILL }
 342         },
 343         { &hf_geneve_flag_oam,
 344           { "Operations, Administration and Management Frame", "geneve.flags.oam",
 345             FT_BOOLEAN, 8, NULL, 0x80,
 346             NULL, HFILL }
 347         },
 348         { &hf_geneve_flag_critical,
 349           { "Critical Options Present", "geneve.flags.critical",
 350             FT_BOOLEAN, 8, NULL, 0x40,
 351             NULL, HFILL }
 352         },
 353         { &hf_geneve_flag_reserved,
 354           { "Reserved", "geneve.flags.reserved",
 355             FT_BOOLEAN, 8, NULL, 0x3F,
 356             NULL, HFILL }
 357         },
 358         { &hf_geneve_proto_type,
 359           { "Protocol Type", "geneve.proto_type",
 360             FT_UINT16, BASE_HEX, VALS(etype_vals), 0x0,
 361             NULL, HFILL }
 362         },
 363         { &hf_geneve_vni,
 364           { "Virtual Network Identifier (VNI)", "geneve.vni",
 365             FT_UINT24, BASE_HEX, NULL, 0x0,
 366             NULL, HFILL }
 367         },
 368         { &hf_geneve_reserved,
 369           { "Reserved", "geneve.reserved",
 370             FT_UINT8, BASE_HEX, NULL, 0x00,
 371             NULL, HFILL }
 372         },
 373         { &hf_geneve_options,
 374           { "Geneve Options", "geneve.options",
 375             FT_BYTES, BASE_NONE, NULL, 0x00,
 376             NULL, HFILL }
 377         },
 378         { &hf_geneve_option_class,
 379           { "Class", "geneve.option.class",
 380             FT_UINT16, BASE_HEX | BASE_RANGE_STRING, RVALS(class_id_names), 0x00,
 381             NULL, HFILL }
 382         },
 383         { &hf_geneve_option_type,
 384           { "Type", "geneve.option.type",
 385             FT_UINT8, BASE_HEX, NULL, 0x00,
 386             NULL, HFILL }
 387         },
 388         { &hf_geneve_option_type_critical,
 389           { "Critical Option", "geneve.option.type.critical",
 390             FT_BOOLEAN, 8, NULL, 0x80,
 391             NULL, HFILL }
 392         },
 393         { &hf_geneve_option_flags,
 394           { "Flags", "geneve.option.flags",
 395             FT_UINT8, BASE_HEX, NULL, 0x00,
 396             NULL, HFILL }
 397         },
 398         { &hf_geneve_option_flags_reserved,
 399           { "Reserved", "geneve.option.flags.reserved",
 400             FT_BOOLEAN, 8, NULL, 0xE0,
 401             NULL, HFILL }
 402         },
 403         { &hf_geneve_option_length,
 404           { "Length", "geneve.option.length",
 405             FT_UINT8, BASE_DEC, NULL, 0x00,
 406             NULL, HFILL }
 407         },
 408         { &hf_geneve_opt_unknown,
 409           { "Unknown Option", "geneve.option.unknown",
 410             FT_BYTES, BASE_NONE, NULL, 0x00,
 411             NULL, HFILL }
 412         },
 413         { &hf_geneve_opt_unknown_data,
 414           { "Option Data", "geneve.option.unknown.data",
 415             FT_BYTES, BASE_NONE, NULL, 0x00,
 416             NULL, HFILL }
 417         },
 418     };
 419
 420     static gint *ett[] = {
 421         &ett_geneve,
 422         &ett_geneve_flags,
 423         &ett_geneve_options,
 424         &ett_geneve_opt_flags,
 425         &ett_geneve_unknown_opt,
 426     };
 427
 428     static ei_register_info ei[] = {
 429        { &ei_geneve_ver_unknown, { "geneve.version.unknown",
 430          PI_PROTOCOL, PI_WARN, "Unknown version", EXPFILL }},
 431        { &ei_geneve_opt_len_invalid, { "geneve.option.length.invalid",
 432          PI_PROTOCOL, PI_WARN, "Invalid length for option", EXPFILL }},
 433     };
 434
 435     expert_module_t *expert_geneve;
 436
 437     /* Register the protocol name and description */
 438     proto_geneve = proto_register_protocol("Generic Network Virtualization Encapsulation",
 439                                           "Geneve", "geneve");
 440
 441     proto_register_field_array(proto_geneve, hf, array_length(hf));
 442     proto_register_subtree_array(ett, array_length(ett));
 443
 444     expert_geneve = expert_register_protocol(proto_geneve);
 445     expert_register_field_array(expert_geneve, ei, array_length(ei));
 446 }
 447
 448 void
 449 proto_reg_handoff_geneve(void)
 450 {
 451     dissector_handle_t geneve_handle;
 452
 453     geneve_handle = create_dissector_handle(dissect_geneve, proto_geneve);
 454     dissector_add_uint("udp.port", UDP_PORT_GENEVE, geneve_handle);
 455     dissector_add_for_decode_as("udp.port", geneve_handle);
 456
 457     ethertype_dissector_table = find_dissector_table("ethertype");
 458 }
 459
 460 /*
 461  * Editor modelines  -  http://www.wireshark.org/tools/modelines.html
 462  *
 463  * Local variables:
 464  * c-basic-offset: 4
 465  * tab-width: 8
 466  * indent-tabs-mode: nil
 467  * End:
 468  *
 469  * vi: set shiftwidth=4 tabstop=8 expandtab:
 470  * :indentSize=4:tabSize=8:noTabs=true:
 471  */