packet-ospf.c

   1 /* packet-ospf.c
   2  * Routines for OSPF packet disassembly
   3  * (c) Copyright Hannes R. Boehm <hannes@boehm.org>
   4  *
   5  * $Id: packet-ospf.c,v 1.22 2000/04/16 22:46:20 guy Exp $
   6  *
   7  * At this time, this module is able to analyze OSPF
   8  * packets as specified in RFC2328. MOSPF (RFC1584) and other
   9  * OSPF Extensions which introduce new Packet types
  10  * (e.g the External Atributes LSA) are not supported.
  11  *
  12  * TOS - support is not fully implemented
  13  *
  14  * Ethereal - Network traffic analyzer
  15  * By Gerald Combs <gerald@zing.org>
  16  * Copyright 1998 Gerald Combs
  17  *
  18  *
  19  * This program is free software; you can redistribute it and/or
  20  * modify it under the terms of the GNU General Public License
  21  * as published by the Free Software Foundation; either version 2
  22  * of the License, or (at your option) any later version.
  23  *
  24  * This program is distributed in the hope that it will be useful,
  25  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  26  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  27  * GNU General Public License for more details.
  28  *
  29  * You should have received a copy of the GNU General Public License
  30  * along with this program; if not, write to the Free Software
  31  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  32  */
  33
  34 #ifdef HAVE_CONFIG_H
  35 # include "config.h"
  36 #endif
  37
  38 #ifdef HAVE_SYS_TYPES_H
  39 # include <sys/types.h>
  40 #endif
  41
  42 #ifdef HAVE_NETINET_IN_H
  43 # include <netinet/in.h>
  44 #endif
  45
  46 #include <stdio.h>
  47 #include <string.h>
  48
  49 #include <glib.h>
  50 #include "packet.h"
  51 #include "packet-ospf.h"
  52 #include "packet-ip.h"
  53 #include "ieee-float.h"
  54
  55 static int proto_ospf = -1;
  56
  57 static gint ett_ospf = -1;
  58 static gint ett_ospf_hdr = -1;
  59 static gint ett_ospf_hello = -1;
  60 static gint ett_ospf_desc = -1;
  61 static gint ett_ospf_lsr = -1;
  62 static gint ett_ospf_lsa = -1;
  63 static gint ett_ospf_lsa_upd = -1;
  64
  65 /* Trees for opaque LSAs */
  66 static gint ett_ospf_lsa_mpls = -1;
  67 static gint ett_ospf_lsa_mpls_router = -1;
  68 static gint ett_ospf_lsa_mpls_link = -1;
  69 static gint ett_ospf_lsa_mpls_link_stlv = -1;
  70
  71 static void dissect_ospf_hello(const u_char*, int, frame_data*, proto_tree*);
  72 static void dissect_ospf_db_desc(const u_char*, int, frame_data*, proto_tree*);
  73 static void dissect_ospf_ls_req(const u_char*, int, frame_data*, proto_tree*);
  74 static void dissect_ospf_ls_upd(const u_char*, int, frame_data*, proto_tree*);
  75 static void dissect_ospf_ls_ack(const u_char*, int, frame_data*, proto_tree*);
  76
  77 /* dissect_ospf_lsa returns the length of the LSA
  78  * if disassemble_body is set to FALSE (e.g. in LSA ACK
  79  * packets), the LSA-header length is returned (20)
  80  */
  81 static int dissect_ospf_lsa(const u_char*, int, frame_data*, proto_tree*, int disassemble_body);
  82
  83 static void
  84 dissect_ospf(const u_char *pd, int offset, frame_data *fd, proto_tree *tree) {
  85     e_ospfhdr ospfh;
  86     e_ospf_crypto *crypto;
  87     int i, saved_len, ospflen;
  88
  89     proto_tree *ospf_tree = NULL;
  90         proto_item *ti;
  91     proto_tree *ospf_header_tree;
  92     char auth_data[(2 * 16) + 1]="";
  93     char *packet_type;
  94     static value_string pt_vals[] = { {OSPF_HELLO,   "Hello Packet"   },
  95                                       {OSPF_DB_DESC, "DB Descr."      },
  96                                       {OSPF_LS_REQ,  "LS Request"     },
  97                                       {OSPF_LS_UPD,  "LS Update"      },
  98                                       {OSPF_LS_ACK,  "LS Acknowledge" },
  99                                       {0,             NULL            } };
 100
 101     memcpy(&ospfh, &pd[offset], sizeof(e_ospfhdr));
 102
 103     packet_type = match_strval(ospfh.packet_type, pt_vals);
 104     if (check_col(fd, COL_PROTOCOL))
 105         col_add_str(fd, COL_PROTOCOL, "OSPF");
 106     if (check_col(fd, COL_INFO)) {
 107         if (packet_type != NULL)
 108             col_add_str(fd, COL_INFO, packet_type);
 109         else
 110             col_add_fstr(fd, COL_INFO, "Unknown (%d)", ospfh.packet_type);
 111     }
 112
 113     if (tree) {
 114         ti = proto_tree_add_item(tree, proto_ospf, offset, ntohs(ospfh.length), NULL);
 115         ospf_tree = proto_item_add_subtree(ti, ett_ospf);
 116
 117         ti = proto_tree_add_text(ospf_tree, offset, OSPF_HEADER_LENGTH, "OSPF Header");
 118         ospf_header_tree = proto_item_add_subtree(ti, ett_ospf_hdr);
 119
 120         proto_tree_add_text(ospf_header_tree, offset, 1, "OSPF Version: %d", ospfh.version);
 121         proto_tree_add_text(ospf_header_tree, offset + 1 , 1, "OSPF Packet Type: %d (%s)",
 122                                                            ospfh.packet_type,
 123                                                            (packet_type != NULL ?
 124                                                              packet_type :
 125                                                              "Unknown"));
 126         proto_tree_add_text(ospf_header_tree, offset + 2 , 2, "Packet Length: %d",
 127                                                            ntohs(ospfh.length));
 128         proto_tree_add_text(ospf_header_tree, offset + 4 , 4, "Source OSPF Router ID: %s",
 129
 130                                                            ip_to_str((guint8 *) &(ospfh.routerid)));
 131         if (!(ospfh.area)) {
 132            proto_tree_add_text(ospf_header_tree, offset + 8 , 4, "Area ID: Backbone");
 133         } else {
 134            proto_tree_add_text(ospf_header_tree, offset + 8 , 4, "Area ID: %s", ip_to_str((guint8 *) &(ospfh.area)));
 135         }
 136         proto_tree_add_text(ospf_header_tree, offset + 12 , 2, "Packet Checksum: 0x%x",
 137               ntohs(ospfh.checksum));
 138         switch( ntohs(ospfh.auth_type) ) {
 139             case OSPF_AUTH_NONE:
 140                  proto_tree_add_text(ospf_header_tree, offset + 14 , 2, "Auth Type: none");
 141                  proto_tree_add_text(ospf_header_tree, offset + 16 , 8, "Auth Data (none)");
 142                  break;
 143             case OSPF_AUTH_SIMPLE:
 144                  proto_tree_add_text(ospf_header_tree, offset + 14 , 2, "Auth Type: simple");
 145                  strncpy(auth_data, (char *) &ospfh.auth_data, 8);
 146                  proto_tree_add_text(ospf_header_tree, offset + 16 , 8, "Auth Data: %s", auth_data);
 147                  break;
 148             case OSPF_AUTH_CRYPT:
 149                  crypto = (e_ospf_crypto *)ospfh.auth_data;
 150                  proto_tree_add_text(ospf_header_tree, offset + 14 , 2, "Auth Type: crypt");
 151                  proto_tree_add_text(ospf_header_tree, offset + 18 , 1, "Auth Key ID: %d",
 152                                      crypto->key_id);
 153                  proto_tree_add_text(ospf_header_tree, offset + 19 , 1, "Auth Data Length: %d",
 154                                      crypto->length);
 155                  proto_tree_add_text(ospf_header_tree, offset + 20 , 4, "Auth Crypto Sequence Number: 0x%lx",
 156                                  (unsigned long)ntohl(crypto->sequence_num));
 157
 158                  ospflen = ntohs(ospfh.length);
 159                  for (i = 0; i < crypto->length && i < (sizeof(auth_data)/2); i++)
 160                      sprintf(&auth_data[i*2],"%02x",pd[offset + ospflen + i]);
 161                  proto_tree_add_text(ospf_header_tree, offset + ospflen , 16, "Auth Data: %s", auth_data);
 162                  break;
 163             default:
 164                  proto_tree_add_text(ospf_header_tree, offset + 14 , 2, "Auth Type (unknown)");
 165                  proto_tree_add_text(ospf_header_tree, offset + 16 , 8, "Auth Data (unknown)");
 166         }
 167
 168     }
 169
 170     /* Temporarily adjust the captured length to match the size of the OSPF
 171      * packet (since the dissect routines use it to work out where the end of
 172      * the ospf packet is).
 173      */
 174     saved_len = pi.captured_len;
 175     if (BYTES_ARE_IN_FRAME(offset, ntohs(ospfh.length))) {
 176       pi.captured_len = offset + ntohs(ospfh.length);
 177     }
 178
 179     /*  Skip over header */
 180     offset += OSPF_HEADER_LENGTH;
 181
 182     switch(ospfh.packet_type){
 183         case OSPF_HELLO:
 184             dissect_ospf_hello(pd, offset, fd, ospf_tree);
 185             break;
 186         case OSPF_DB_DESC:
 187             dissect_ospf_db_desc(pd, offset, fd, ospf_tree);
 188             break;
 189         case OSPF_LS_REQ:
 190             dissect_ospf_ls_req(pd, offset, fd, ospf_tree);
 191             break;
 192         case OSPF_LS_UPD:
 193             dissect_ospf_ls_upd(pd, offset, fd, ospf_tree);
 194             break;
 195         case OSPF_LS_ACK:
 196             dissect_ospf_ls_ack(pd, offset, fd, ospf_tree);
 197             break;
 198         default:
 199             pi.captured_len = saved_len;
 200             dissect_data(pd, offset, fd, tree);
 201     }
 202     pi.captured_len = saved_len;
 203 }
 204
 205 static void
 206 dissect_ospf_hello(const u_char *pd, int offset, frame_data *fd, proto_tree *tree) {
 207     e_ospf_hello ospfhello;
 208     guint32 *ospfneighbor;
 209     char options[20]="";
 210     int options_offset;
 211
 212     proto_tree *ospf_hello_tree;
 213         proto_item *ti;
 214
 215     memcpy(&ospfhello, &pd[offset], sizeof(e_ospf_hello));
 216
 217     if (tree) {
 218         ti = proto_tree_add_text(tree, offset, END_OF_FRAME, "OSPF Hello Packet");
 219         ospf_hello_tree = proto_item_add_subtree(ti, ett_ospf_hello);
 220
 221
 222         proto_tree_add_text(ospf_hello_tree, offset , 4, "Network Mask: %s",  ip_to_str((guint8 *) &ospfhello.network_mask));
 223         proto_tree_add_text(ospf_hello_tree, offset + 4, 2, "Hello Interval: %d seconds",  ntohs(ospfhello.hellointervall));
 224
 225         /* ATTENTION !!! no check for length of options string */
 226         options_offset=0;
 227         if(( ospfhello.options & OSPF_OPTIONS_E ) == OSPF_OPTIONS_E){
 228             strcpy( (char *)(options + options_offset), "E");
 229             options_offset+=1;
 230         }
 231         if(( ospfhello.options & OSPF_OPTIONS_MC ) == OSPF_OPTIONS_MC){
 232             strcpy((char *) (options + options_offset), "/MC");
 233             options_offset+=3;
 234         }
 235         if(( ospfhello.options & OSPF_OPTIONS_NP ) == OSPF_OPTIONS_NP){
 236             strcpy((char *) (options + options_offset), "/NP");
 237             options_offset+=3;
 238         }
 239         if(( ospfhello.options & OSPF_OPTIONS_EA ) == OSPF_OPTIONS_EA){
 240             strcpy((char *) (options + options_offset) , "/EA");
 241             options_offset+=3;
 242         }
 243         if(( ospfhello.options & OSPF_OPTIONS_DC ) == OSPF_OPTIONS_DC){
 244             strcpy((char *) (options + options_offset) , "/DC");
 245             options_offset+=3;
 246         }
 247
 248         proto_tree_add_text(ospf_hello_tree, offset + 6, 1, "Options: %d (%s)",  ospfhello.options, options);
 249         proto_tree_add_text(ospf_hello_tree, offset + 7, 1, "Router Priority: %d",  ospfhello.priority);
 250         proto_tree_add_text(ospf_hello_tree, offset + 8, 4, "Router Dead Interval: %ld seconds",  (long)ntohl(ospfhello.dead_interval));
 251         proto_tree_add_text(ospf_hello_tree, offset + 12, 4, "Designated Router: %s",  ip_to_str((guint8 *) &ospfhello.drouter));
 252         proto_tree_add_text(ospf_hello_tree, offset + 16, 4, "Backup Designated Router: %s",  ip_to_str((guint8 *) &ospfhello.bdrouter));
 253
 254
 255         offset+=20;
 256         while(((int)(pi.captured_len - offset)) >= 4){
 257             ospfneighbor=(guint32 *) &pd[offset];
 258             proto_tree_add_text(ospf_hello_tree, offset, 4, "Active Neighbor: %s",  ip_to_str((guint8 *) ospfneighbor));
 259             offset+=4;
 260         }
 261     }
 262 }
 263
 264 static void
 265 dissect_ospf_db_desc(const u_char *pd, int offset, frame_data *fd, proto_tree *tree) {
 266     e_ospf_dbd ospf_dbd;
 267     char options[20]="";
 268     int options_offset;
 269     char flags[20]="";
 270     int flags_offset;
 271
 272     proto_tree *ospf_db_desc_tree=NULL;
 273         proto_item *ti;
 274
 275     memcpy(&ospf_dbd, &pd[offset], sizeof(e_ospf_dbd));
 276
 277     if (tree) {
 278         ti = proto_tree_add_text(tree, offset, END_OF_FRAME, "OSPF DB Description");
 279         ospf_db_desc_tree = proto_item_add_subtree(ti, ett_ospf_desc);
 280
 281         proto_tree_add_text(ospf_db_desc_tree, offset, 2, "Interface MTU: %d", ntohs(ospf_dbd.interface_mtu) );
 282
 283
 284         options_offset=0;
 285         if(( ospf_dbd.options & OSPF_OPTIONS_E ) == OSPF_OPTIONS_E){
 286             strcpy( (char *)(options + options_offset), "_E_");
 287             options_offset+=1;
 288         }
 289         if(( ospf_dbd.options & OSPF_OPTIONS_MC ) == OSPF_OPTIONS_MC){
 290             strcpy((char *) (options + options_offset), "_MC_");
 291             options_offset+=3;
 292         }
 293         if(( ospf_dbd.options & OSPF_OPTIONS_NP ) == OSPF_OPTIONS_NP){
 294             strcpy((char *) (options + options_offset), "_NP_");
 295             options_offset+=3;
 296         }
 297         if(( ospf_dbd.options & OSPF_OPTIONS_EA ) == OSPF_OPTIONS_EA){
 298             strcpy((char *) (options + options_offset) , "_EA_");
 299             options_offset+=3;
 300         }
 301         if(( ospf_dbd.options & OSPF_OPTIONS_DC ) == OSPF_OPTIONS_DC){
 302             strcpy((char *) (options + options_offset) , "_DC_");
 303             options_offset+=3;
 304         }
 305
 306         proto_tree_add_text(ospf_db_desc_tree, offset + 2 , 1, "Options: %d (%s)", ospf_dbd.options, options );
 307
 308
 309         flags_offset=0;
 310         if(( ospf_dbd.flags & OSPF_DBD_FLAG_MS ) == OSPF_DBD_FLAG_MS){
 311             strcpy( (char *)(flags + flags_offset), "_I_");
 312             flags_offset+=1;
 313         }
 314         if(( ospf_dbd.flags & OSPF_DBD_FLAG_M ) == OSPF_DBD_FLAG_M){
 315             strcpy((char *) (flags + flags_offset), "_M_");
 316             flags_offset+=3;
 317         }
 318         if(( ospf_dbd.flags & OSPF_DBD_FLAG_I ) == OSPF_DBD_FLAG_I){
 319             strcpy((char *) (flags + flags_offset), "_I_");
 320             flags_offset+=3;
 321         }
 322
 323         proto_tree_add_text(ospf_db_desc_tree, offset + 3 , 1, "Flags: %d (%s)", ospf_dbd.flags, flags );
 324         proto_tree_add_text(ospf_db_desc_tree, offset + 4 , 4, "DD Sequence: %ld", (long)ntohl(ospf_dbd.dd_sequence) );
 325     }
 326     /* LS Headers will be processed here */
 327     /* skip to the end of DB-Desc header */
 328     offset+=8;
 329     while( ((int) (pi.captured_len - offset)) >= OSPF_LSA_HEADER_LENGTH ) {
 330        dissect_ospf_lsa(pd, offset, fd, tree, FALSE);
 331        offset+=OSPF_LSA_HEADER_LENGTH;
 332     }
 333 }
 334
 335 static void
 336 dissect_ospf_ls_req(const u_char *pd, int offset, frame_data *fd, proto_tree *tree) {
 337     e_ospf_ls_req ospf_lsr;
 338
 339     proto_tree *ospf_lsr_tree;
 340         proto_item *ti;
 341
 342
 343     /* zero or more LS requests may be within a LS Request */
 344     /* we place every request for a LSA in a single subtree */
 345     if (tree) {
 346         while( ((int) (pi.captured_len - offset)) >= OSPF_LS_REQ_LENGTH ){
 347              memcpy(&ospf_lsr, &pd[offset], sizeof(e_ospf_ls_req));
 348              ti = proto_tree_add_text(tree, offset, OSPF_LS_REQ_LENGTH, "Link State Request");
 349              ospf_lsr_tree = proto_item_add_subtree(ti, ett_ospf_lsr);
 350
 351              switch( ntohl( ospf_lsr.ls_type ) ){
 352                  case OSPF_LSTYPE_ROUTER:
 353                      proto_tree_add_text(ospf_lsr_tree, offset, 4, "LS Type: Router-LSA (%ld)",
 354                                        (long)ntohl( ospf_lsr.ls_type ) );
 355                      break;
 356                  case OSPF_LSTYPE_NETWORK:
 357                      proto_tree_add_text(ospf_lsr_tree, offset, 4, "LS Type: Network-LSA (%ld)",
 358                                        (long)ntohl( ospf_lsr.ls_type ) );
 359                      break;
 360                  case OSPF_LSTYPE_SUMMERY:
 361                      proto_tree_add_text(ospf_lsr_tree, offset, 4, "LS Type: Summary-LSA (IP network) (%ld)",
 362                                        (long)ntohl( ospf_lsr.ls_type ) );
 363                      break;
 364                  case OSPF_LSTYPE_ASBR:
 365                      proto_tree_add_text(ospf_lsr_tree, offset, 4, "LS Type: Summary-LSA (ASBR) (%ld)",
 366                                        (long)ntohl( ospf_lsr.ls_type ) );
 367                      break;
 368                  case OSPF_LSTYPE_ASEXT:
 369                      proto_tree_add_text(ospf_lsr_tree, offset, 4, "LS Type: AS-External-LSA (ASBR) (%ld)",
 370                                        (long)ntohl( ospf_lsr.ls_type ) );
 371                      break;
 372                  default:
 373                      proto_tree_add_text(ospf_lsr_tree, offset, 4, "LS Type: %ld (unknown)",
 374                                        (long)ntohl( ospf_lsr.ls_type ) );
 375              }
 376
 377              proto_tree_add_text(ospf_lsr_tree, offset + 4, 4, "Link State ID : %s",
 378                                          ip_to_str((guint8 *) &(ospf_lsr.ls_id)));
 379              proto_tree_add_text(ospf_lsr_tree, offset + 8, 4, "Advertising Router : %s",
 380                                          ip_to_str((guint8 *) &(ospf_lsr.adv_router)));
 381
 382              offset+=12;
 383         }
 384     }
 385 }
 386
 387 static void
 388 dissect_ospf_ls_upd(const u_char *pd, int offset, frame_data *fd, proto_tree *tree) {
 389     e_ospf_lsa_upd_hdr upd_hdr;
 390     guint32 lsa_counter;
 391
 392     proto_tree *ospf_lsa_upd_tree=NULL;
 393         proto_item *ti;
 394
 395     memcpy(&upd_hdr, &pd[offset], sizeof(e_ospf_lsa_upd_hdr));
 396
 397     if (tree) {
 398         ti = proto_tree_add_text(tree, offset, END_OF_FRAME, "LS Update Packet");
 399         ospf_lsa_upd_tree = proto_item_add_subtree(ti, ett_ospf_lsa_upd);
 400
 401         proto_tree_add_text(ospf_lsa_upd_tree, offset, 4, "Nr oF LSAs: %ld", (long)ntohl(upd_hdr.lsa_nr) );
 402     }
 403     /* skip to the beginning of the first LSA */
 404     offset+=4; /* the LS Upd PAcket contains only a 32 bit #LSAs field */
 405
 406     lsa_counter = 0;
 407     while(lsa_counter < ntohl(upd_hdr.lsa_nr)){
 408         offset+=dissect_ospf_lsa(pd, offset, fd, ospf_lsa_upd_tree, TRUE);
 409         lsa_counter += 1;
 410     }
 411 }
 412
 413 static void
 414 dissect_ospf_ls_ack(const u_char *pd, int offset, frame_data *fd, proto_tree *tree) {
 415
 416     /* the body of a LS Ack packet simply contains zero or more LSA Headers */
 417     while( ((int)(pi.captured_len - offset)) >= OSPF_LSA_HEADER_LENGTH ) {
 418        dissect_ospf_lsa(pd, offset, fd, tree, FALSE);
 419        offset+=OSPF_LSA_HEADER_LENGTH;
 420     }
 421
 422 }
 423
 424 /*
 425  * Returns if an LSA is opaque, i.e. requires special treatment
 426  */
 427 int is_opaque(int lsa_type)
 428 {
 429     return (lsa_type >= 9 && lsa_type <= 11);
 430 }
 431
 432 /* MPLS/TE TLV types */
 433 #define MPLS_TLV_ROUTER    1
 434 #define MPLS_TLV_LINK      2
 435
 436 /* MPLS/TE Link STLV types */
 437 enum {
 438     MPLS_LINK_TYPE       = 1,
 439     MPLS_LINK_ID,
 440     MPLS_LINK_LOCAL_IF,
 441     MPLS_LINK_REMOTE_IF,
 442     MPLS_LINK_TE_METRIC,
 443     MPLS_LINK_MAX_BW,
 444     MPLS_LINK_MAX_RES_BW,
 445     MPLS_LINK_UNRES_BW,
 446     MPLS_LINK_COLOR,
 447 };
 448
 449 static value_string mpls_link_stlv_str[] = {
 450     {MPLS_LINK_TYPE, "Link Type"},
 451     {MPLS_LINK_ID, "Link ID"},
 452     {MPLS_LINK_LOCAL_IF, "Local Interface IP Address"},
 453     {MPLS_LINK_REMOTE_IF, "Remote Interface IP Address"},
 454     {MPLS_LINK_TE_METRIC, "Traffic Engineering Metric"},
 455     {MPLS_LINK_MAX_BW, "Maximum Bandwidth"},
 456     {MPLS_LINK_MAX_RES_BW, "Maximum Reservable Bandwidth"},
 457     {MPLS_LINK_UNRES_BW, "Unreserved Bandwidth"},
 458     {MPLS_LINK_COLOR, "Resource Class/Color"},
 459 };
 460
 461 /*
 462  * Dissect MPLS/TE opaque LSA
 463  */
 464
 465 void dissect_ospf_lsa_mpls(const u_char *pd,
 466                           int offset,
 467                           frame_data *fd,
 468                           proto_tree *tree,
 469                           e_ospf_lsa_hdr *lsa_hdr) {
 470     proto_item *ti;
 471     proto_tree *mpls_tree;
 472     proto_tree *tlv_tree;
 473     proto_tree *stlv_tree;
 474
 475     int length;
 476     int tlv_type;
 477     int tlv_length;
 478
 479     int link_len;
 480     int stlv_type, stlv_len;
 481     char *stlv_name;
 482     int i;
 483
 484     ti = proto_tree_add_text(tree, offset, ntohs(lsa_hdr->length) - 20,
 485                              "MPLS Traffic Engineering LSA");
 486     mpls_tree = proto_item_add_subtree(ti, ett_ospf_lsa_mpls);
 487
 488     for (length = 0; length < ntohs(lsa_hdr->length) - 20; length += 4) {
 489         tlv_type = pntohs(pd+offset+length);
 490         tlv_length = pntohs(pd+offset+length + 2);
 491
 492         switch(tlv_type) {
 493         case MPLS_TLV_ROUTER:
 494             ti = proto_tree_add_text(mpls_tree, offset+length, tlv_length+4,
 495                                      "Router Address: %s",
 496                                      ip_to_str((pd+offset+length+4)));
 497             tlv_tree = proto_item_add_subtree(ti, ett_ospf_lsa_mpls_router);
 498             proto_tree_add_text(tlv_tree, offset+length, 2, "TLV Type: 1 - Router Address");
 499             proto_tree_add_text(tlv_tree, offset+length+2, 2, "TLV Length: %d", tlv_length);
 500             proto_tree_add_text(tlv_tree, offset+length+4, 4, "Router Address: %s",
 501                                 ip_to_str((pd+offset+length+4)));
 502             break;
 503         case MPLS_TLV_LINK:
 504             ti = proto_tree_add_text(mpls_tree, offset+length, tlv_length+4,
 505                                      "Link Information");
 506             tlv_tree = proto_item_add_subtree(ti, ett_ospf_lsa_mpls_link);
 507             proto_tree_add_text(tlv_tree, offset+length, 2, "TLV Type: 2 - Link Information");
 508             proto_tree_add_text(tlv_tree, offset+length+2, 2, "TLV Length: %d", tlv_length);
 509
 510             /* Walk down the sub-TLVs for link information */
 511             for (link_len = length + 4; link_len < length + 4 + tlv_length; link_len += 4) {
 512                 stlv_type = pntohs(pd+offset+link_len);
 513                 stlv_len = pntohs(pd+offset+link_len + 2);
 514                 stlv_name = val_to_str(stlv_type, mpls_link_stlv_str, "Unknown sub-TLV");
 515                 switch(stlv_type) {
 516
 517                 case MPLS_LINK_TYPE:
 518                     ti = proto_tree_add_text(tlv_tree, offset+link_len, stlv_len+4,
 519                                              "%s: %d", stlv_name,
 520                                              *((guint8 *)pd + offset + link_len + 4));
 521                     stlv_tree = proto_item_add_subtree(ti, ett_ospf_lsa_mpls_link_stlv);
 522                     proto_tree_add_text(stlv_tree, offset+link_len, 2,
 523                                         "TLV Type: %d: %s", stlv_type, stlv_name);
 524                     proto_tree_add_text(stlv_tree, offset+link_len+2, 2, "TLV Length: %d", stlv_len);
 525                     proto_tree_add_text(stlv_tree, offset+link_len+4, 1, "%s: %d", stlv_name,
 526                                         *((guint8 *)pd + offset + link_len + 4));
 527                     break;
 528
 529                 case MPLS_LINK_ID:
 530                     ti = proto_tree_add_text(tlv_tree, offset+link_len, stlv_len+4,
 531                                              "%s: %s (%x)", stlv_name,
 532                                              ip_to_str(pd + offset + link_len + 4),
 533                                              pntohl(pd + offset + link_len + 4));
 534                     stlv_tree = proto_item_add_subtree(ti, ett_ospf_lsa_mpls_link_stlv);
 535                     proto_tree_add_text(stlv_tree, offset+link_len, 2,
 536                                         "TLV Type: %d: %s", stlv_type, stlv_name);
 537                     proto_tree_add_text(stlv_tree, offset+link_len+2, 2, "TLV Length: %d", stlv_len);
 538                     proto_tree_add_text(stlv_tree, offset+link_len+4, 4, "%s: %s (%x)", stlv_name,
 539                                         ip_to_str(pd + offset + link_len + 4),
 540                                         pntohl(pd + offset + link_len + 4));
 541                     break;
 542
 543                 case MPLS_LINK_LOCAL_IF:
 544                 case MPLS_LINK_REMOTE_IF:
 545                     ti = proto_tree_add_text(tlv_tree, offset+link_len, stlv_len+4,
 546                                              "%s: %s", stlv_name,
 547                                              ip_to_str(pd+offset+link_len+4));
 548                     stlv_tree = proto_item_add_subtree(ti, ett_ospf_lsa_mpls_link_stlv);
 549                     proto_tree_add_text(stlv_tree, offset+link_len, 2,
 550                                         "TLV Type: %d: %s", stlv_type, stlv_name);
 551                     proto_tree_add_text(stlv_tree, offset+link_len+2, 2, "TLV Length: %d", stlv_len);
 552                     proto_tree_add_text(stlv_tree, offset+link_len+4, 4, "%s: %s", stlv_name,
 553                                         ip_to_str(pd+offset+link_len+4));
 554
 555                     break;
 556
 557                 case MPLS_LINK_TE_METRIC:
 558                 case MPLS_LINK_COLOR:
 559                     ti = proto_tree_add_text(tlv_tree, offset+link_len, stlv_len+4,
 560                                              "%s: %d", stlv_name,
 561                                              pntohl(pd + offset + link_len + 4));
 562                     stlv_tree = proto_item_add_subtree(ti, ett_ospf_lsa_mpls_link_stlv);
 563                     proto_tree_add_text(stlv_tree, offset+link_len, 2,
 564                                         "TLV Type: %d: %s", stlv_type, stlv_name);
 565                     proto_tree_add_text(stlv_tree, offset+link_len+2, 2, "TLV Length: %d", stlv_len);
 566                     proto_tree_add_text(stlv_tree, offset+link_len+4, 4, "%s: %d", stlv_name,
 567                                         pntohl(pd + offset + link_len + 4));
 568                     break;
 569
 570                 case MPLS_LINK_MAX_BW:
 571                 case MPLS_LINK_MAX_RES_BW:
 572                     ti = proto_tree_add_text(tlv_tree, offset+link_len, stlv_len+4,
 573                                              "%s: %ld", stlv_name,
 574                                              pieee_to_long(pd + offset + link_len + 4));
 575                     stlv_tree = proto_item_add_subtree(ti, ett_ospf_lsa_mpls_link_stlv);
 576                     proto_tree_add_text(stlv_tree, offset+link_len, 2,
 577                                         "TLV Type: %d: %s", stlv_type, stlv_name);
 578                     proto_tree_add_text(stlv_tree, offset+link_len+2, 2, "TLV Length: %d", stlv_len);
 579                     proto_tree_add_text(stlv_tree, offset+link_len+4, 4, "%s: %ld", stlv_name,
 580                                         pieee_to_long(pd + offset + link_len + 4));
 581                     break;
 582
 583                 case MPLS_LINK_UNRES_BW:
 584                     ti = proto_tree_add_text(tlv_tree, offset+link_len, stlv_len+4,
 585                                              "%s", stlv_name);
 586                     stlv_tree = proto_item_add_subtree(ti, ett_ospf_lsa_mpls_link_stlv);
 587                     proto_tree_add_text(stlv_tree, offset+link_len, 2,
 588                                         "TLV Type: %d: %s", stlv_type, stlv_name);
 589                     proto_tree_add_text(stlv_tree, offset+link_len+2, 2, "TLV Length: %d", stlv_len);
 590                     for (i=0; i<8; i++)
 591                         proto_tree_add_text(stlv_tree, offset+link_len+4+(i*4), 4,
 592                                             "Pri %d: %ld", i,
 593                                             pieee_to_long(pd + offset + link_len + 4 + i*4));
 594                     break;
 595
 596                 default:
 597                     proto_tree_add_text(tlv_tree, offset+link_len, stlv_len+4,
 598                                         "Unknown Link sub-TLV: %d", stlv_type);
 599                 }
 600                 link_len += ((stlv_len+3)/4)*4;
 601             }
 602
 603             break;
 604
 605         default:
 606             ti = proto_tree_add_text(mpls_tree, offset+length, tlv_length+4,
 607                                      "Unknown LSA: %d", tlv_type);
 608             tlv_tree = proto_item_add_subtree(ti, ett_ospf_lsa_mpls_link);
 609             proto_tree_add_text(tlv_tree, offset+length, 2, "TLV Type: %d - Unknown", tlv_type);
 610             proto_tree_add_text(tlv_tree, offset+length+2, 2, "TLV Length: %d", tlv_length);
 611             proto_tree_add_text(tlv_tree, offset+length+4, tlv_length, "TLV Data");
 612             break;
 613         }
 614
 615         length += tlv_length;
 616
 617     }
 618 }
 619
 620 /*
 621  * Dissect opaque LSAs
 622  */
 623 void dissect_ospf_lsa_opaque(const u_char *pd,
 624                             int offset,
 625                             frame_data *fd,
 626                             proto_tree *tree,
 627                             e_ospf_lsa_hdr *lsa_hdr) {
 628     guint8 opaque_id = *((guint8 *) &(lsa_hdr->ls_id));
 629
 630     switch(opaque_id) {
 631
 632     case OSPF_LSA_MPLS_TE:
 633         dissect_ospf_lsa_mpls(pd, offset, fd, tree, lsa_hdr);
 634         break;
 635
 636     default:
 637         proto_tree_add_text(tree, offset, END_OF_FRAME, "Unknown LSA Type");
 638         break;
 639     } /* switch on opaque LSA id */
 640 }
 641
 642 static int
 643 dissect_ospf_lsa(const u_char *pd, int offset, frame_data *fd, proto_tree *tree, int disassemble_body) {
 644     e_ospf_lsa_hdr       lsa_hdr;
 645     char                *lsa_type;
 646     int                  lsa_end;
 647
 648     /* data strutures for the router LSA */
 649     e_ospf_router_lsa           router_lsa;
 650     e_ospf_router_data          router_data;
 651     e_ospf_router_metric        tos_data;
 652     guint16                     link_counter;
 653     guint8                      tos_counter;
 654     char                        *link_type;
 655     char                        *link_id;
 656
 657     /* data structures for the network lsa */
 658     e_ospf_network_lsa  network_lsa;
 659     guint32             *attached_router;
 660
 661     /* data structures for the summary and ASBR LSAs */
 662     e_ospf_summary_lsa  summary_lsa;
 663
 664     /* data structures for the AS-External LSA */
 665     e_ospf_asexternal_lsa       asext_lsa;
 666     guint32                   asext_metric;
 667
 668     /* data structures for opaque LSA */
 669     guint32                     ls_id;
 670
 671     proto_tree *ospf_lsa_tree;
 672         proto_item *ti;
 673
 674     memcpy(&lsa_hdr, &pd[offset], sizeof(e_ospf_lsa_hdr));
 675
 676
 677
 678     switch(lsa_hdr.ls_type) {
 679         case OSPF_LSTYPE_ROUTER:
 680             lsa_type="Router LSA";
 681             break;
 682         case OSPF_LSTYPE_NETWORK:
 683             lsa_type="Network LSA";
 684             break;
 685         case OSPF_LSTYPE_SUMMERY:
 686             lsa_type="Summary LSA";
 687             break;
 688         case OSPF_LSTYPE_ASBR:
 689             lsa_type="ASBR LSA";
 690             break;
 691         case OSPF_LSTYPE_ASEXT:
 692             lsa_type="AS-external-LSA";
 693             break;
 694         case OSPF_LSTYPE_OP_LINKLOCAL:
 695             lsa_type="Opaque LSA, Link-local scope";
 696             break;
 697         case OSPF_LSTYPE_OP_AREALOCAL:
 698             lsa_type="Opaque LSA, Area-local scope";
 699             break;
 700         case OSPF_LSTYPE_OP_ASWIDE:
 701             lsa_type="Opaque LSA, AS-wide scope";
 702             break;
 703         default:
 704             lsa_type="unknown";
 705     }
 706
 707     if (tree) {
 708         if(disassemble_body){
 709              ti = proto_tree_add_text(tree, offset, ntohs(lsa_hdr.length),
 710                                                       "%s (Type: %d)", lsa_type, lsa_hdr.ls_type);
 711         } else {
 712              ti = proto_tree_add_text(tree, offset, OSPF_LSA_HEADER_LENGTH, "LSA Header");
 713         }
 714         ospf_lsa_tree = proto_item_add_subtree(ti, ett_ospf_lsa);
 715
 716
 717         proto_tree_add_text(ospf_lsa_tree, offset, 2, "LS Age: %d seconds", ntohs(lsa_hdr.ls_age));
 718         proto_tree_add_text(ospf_lsa_tree, offset + 2, 1, "Options: %d ", lsa_hdr.options);
 719         proto_tree_add_text(ospf_lsa_tree, offset + 3, 1, "LSA Type: %d (%s)", lsa_hdr.ls_type, lsa_type);
 720
 721         if (is_opaque(lsa_hdr.ls_type)) {
 722             ls_id = ntohl(lsa_hdr.ls_id);
 723             proto_tree_add_text(ospf_lsa_tree, offset + 4, 1, "Link State ID Opaque Type: %u ",
 724                                 (ls_id >> 24) & 0xff);
 725             proto_tree_add_text(ospf_lsa_tree, offset + 5, 3, "Link State ID Opaque ID: %u ",
 726                                 ls_id & 0xffffff);
 727         } else
 728             proto_tree_add_text(ospf_lsa_tree, offset + 4, 4, "Link State ID: %s ",
 729                                 ip_to_str((guint8 *) &(lsa_hdr.ls_id)));
 730
 731         proto_tree_add_text(ospf_lsa_tree, offset + 8, 4, "Advertising Router: %s ",
 732                                                      ip_to_str((guint8 *) &(lsa_hdr.adv_router)));
 733         proto_tree_add_text(ospf_lsa_tree, offset + 12, 4, "LS Sequence Number: 0x%04lx ",
 734                                                      (unsigned long)ntohl(lsa_hdr.ls_seq));
 735         proto_tree_add_text(ospf_lsa_tree, offset + 16, 2, "LS Checksum: %d ", ntohs(lsa_hdr.ls_checksum));
 736
 737         proto_tree_add_text(ospf_lsa_tree, offset + 18, 2, "Length: %d ", ntohs(lsa_hdr.length));
 738
 739         if(!disassemble_body){
 740            return OSPF_LSA_HEADER_LENGTH;
 741         }
 742
 743         lsa_end = offset + ntohs(lsa_hdr.length);
 744         /* the LSA body starts after 20 bytes of LSA Header */
 745         offset+=20;
 746
 747         switch(lsa_hdr.ls_type){
 748             case(OSPF_LSTYPE_ROUTER):
 749                 memcpy(&router_lsa, &pd[offset], sizeof(e_ospf_router_lsa));
 750
 751                 /* again: flags should be secified in detail */
 752                 proto_tree_add_text(ospf_lsa_tree, offset, 1, "Flags: 0x%02x ", router_lsa.flags);
 753                 proto_tree_add_text(ospf_lsa_tree, offset + 2, 2, "Nr. of Links: %d ",
 754                                                                    ntohs(router_lsa.nr_links));
 755                 offset += 4;
 756                 /* router_lsa.nr_links links follow
 757                  * maybe we should put each of the links into its own subtree ???
 758                  */
 759                 for(link_counter = 1 ; link_counter <= ntohs(router_lsa.nr_links); link_counter++){
 760
 761                     memcpy(&router_data, &pd[offset], sizeof(e_ospf_router_data));
 762                     /* check the Link Type and ID */
 763                     switch(router_data.link_type) {
 764                         case OSPF_LINK_PTP:
 765                             link_type="Point-to-point connection to another router";
 766                             link_id="Neighboring router's Router ID";
 767                             break;
 768                         case OSPF_LINK_TRANSIT:
 769                             link_type="Connection to a transit network";
 770                             link_id="IP address of Designated Router";
 771                             break;
 772                         case OSPF_LINK_STUB:
 773                             link_type="Connection to a stub network";
 774                             link_id="IP network/subnet number";
 775                             break;
 776                         case OSPF_LINK_VIRTUAL:
 777                             link_type="Virtual link";
 778                             link_id="Neighboring router's Router ID";
 779                             break;
 780                         default:
 781                             link_type="unknown link type";
 782                             link_id="unknown link id";
 783                     }
 784
 785                     proto_tree_add_text(ospf_lsa_tree, offset, 4, "%s: %s", link_id,
 786                                                    ip_to_str((guint8 *) &(router_data.link_id)));
 787
 788                     /* link_data should be specified in detail (e.g. network mask) (depends on link type)*/
 789                     proto_tree_add_text(ospf_lsa_tree, offset + 4, 4, "Link Data: %s",
 790                                                    ip_to_str((guint8 *) &(router_data.link_data)));
 791
 792                     proto_tree_add_text(ospf_lsa_tree, offset + 8, 1, "Link Type: %d - %s",
 793                                                               router_data.link_type, link_type);
 794                     proto_tree_add_text(ospf_lsa_tree, offset + 9, 1, "Nr. of TOS metrics: %d", router_data.nr_tos);
 795                     proto_tree_add_text(ospf_lsa_tree, offset + 10, 2, "TOS 0 metric: %d", ntohs( router_data.tos0_metric ));
 796
 797                     offset += 12;
 798
 799                     /* router_data.nr_tos metrics may follow each link
 800                      * ATTENTION: TOS metrics are not tested (I don't have TOS based routing)
 801                      * please send me a mail if it is/isn't working
 802                      */
 803
 804                     for(tos_counter = 1 ; link_counter <= ntohs(router_data.nr_tos); tos_counter++){
 805                         memcpy(&tos_data, &pd[offset], sizeof(e_ospf_router_metric));
 806                         proto_tree_add_text(ospf_lsa_tree, offset, 1, "TOS: %d, Metric: %d",
 807                                                 tos_data.tos, ntohs(tos_data.metric));
 808                         offset += 4;
 809                     }
 810                 }
 811                 break;
 812             case(OSPF_LSTYPE_NETWORK):
 813                 memcpy(&network_lsa, &pd[offset], sizeof(e_ospf_network_lsa));
 814                 proto_tree_add_text(ospf_lsa_tree, offset, 4, "Netmask: %s",
 815                                                  ip_to_str((guint8 *) &(network_lsa.network_mask)));
 816                 offset += 4;
 817
 818                 while( (lsa_end - offset) >= 4){
 819                     attached_router = (guint32 *) &pd[offset];
 820                     proto_tree_add_text(ospf_lsa_tree, offset, 4, "Attached Router: %s",
 821                                                  ip_to_str((guint8 *) attached_router));
 822                     offset += 4;
 823                 }
 824                 break;
 825             case(OSPF_LSTYPE_SUMMERY):
 826                 /* Type 3 and 4 LSAs have the same format */
 827             case(OSPF_LSTYPE_ASBR):
 828                 memcpy(&summary_lsa, &pd[offset], sizeof(e_ospf_summary_lsa));
 829                 proto_tree_add_text(ospf_lsa_tree, offset, 4, "Netmask: %s",
 830                                                  ip_to_str((guint8 *) &(summary_lsa.network_mask)));
 831                 /* returns only the TOS 0 metric (even if there are more TOS metrics) */
 832                 break;
 833             case(OSPF_LSTYPE_ASEXT):
 834                 memcpy(&summary_lsa, &pd[offset], sizeof(e_ospf_summary_lsa));
 835                 proto_tree_add_text(ospf_lsa_tree, offset, 4, "Netmask: %s",
 836                                                   ip_to_str((guint8 *) &(summary_lsa.network_mask)));
 837
 838                 /* asext_lsa = (e_ospf_asexternal_lsa *) &pd[offset + 4]; */
 839                 memcpy(&asext_lsa, &pd[offset + 4], sizeof(asext_lsa));
 840                 if( (asext_lsa.options & 128) == 128 ) { /* check wether or not E bit is set */
 841                    proto_tree_add_text(ospf_lsa_tree, offset, 1,
 842                             "External Type: Type 2 (metric is larger than any other link state path)");
 843                 } else {
 844                    proto_tree_add_text(ospf_lsa_tree, offset + 4, 1,
 845                             "External Type: Type 1 (metric is specified in the same units as interface cost)");
 846                 }
 847                 /* the metric field of a AS-external LAS is specified in 3 bytes -> not well aligned */
 848                 /* this routine returns only the TOS 0 metric (even if there are more TOS metrics) */
 849                 memcpy(&asext_metric, &pd[offset+4], 4);
 850
 851                 /* erase the leading 8 bits (the dont belong to the metric */
 852                 asext_metric = ntohl(asext_metric) & 0x00ffffff ;
 853
 854                 proto_tree_add_text(ospf_lsa_tree, offset + 5,  3,"Metric: %d", asext_metric);
 855                 proto_tree_add_text(ospf_lsa_tree, offset + 8,  4,"Forwarding Address: %s",
 856                                                  ip_to_str((guint8 *) &(asext_lsa.gateway)));
 857                 proto_tree_add_text(ospf_lsa_tree, offset + 12, 4,"External Route Tag: %ld", (long)ntohl(asext_lsa.external_tag));
 858
 859                 break;
 860
 861         case OSPF_LSTYPE_OP_LINKLOCAL:
 862         case OSPF_LSTYPE_OP_AREALOCAL:
 863         case OSPF_LSTYPE_OP_ASWIDE:
 864             dissect_ospf_lsa_opaque(pd, offset, fd, ospf_lsa_tree, &lsa_hdr);
 865             break;
 866
 867         default:
 868                /* unknown LSA type */
 869                 proto_tree_add_text(ospf_lsa_tree, offset, END_OF_FRAME, "Unknown LSA Type");
 870         }
 871     }
 872     /* return the length of this LSA */
 873     return ntohs(lsa_hdr.length);
 874 }
 875
 876 void
 877 proto_register_ospf(void)
 878 {
 879 /*        static hf_register_info hf[] = {
 880                 { &variable,
 881                 { "Name",           "ospf.abbreviation", TYPE, VALS_POINTER }},
 882         };*/
 883         static gint *ett[] = {
 884                 &ett_ospf,
 885                 &ett_ospf_hdr,
 886                 &ett_ospf_hello,
 887                 &ett_ospf_desc,
 888                 &ett_ospf_lsr,
 889                 &ett_ospf_lsa,
 890                 &ett_ospf_lsa_upd,
 891                 &ett_ospf_lsa_mpls,
 892                 &ett_ospf_lsa_mpls_router,
 893                 &ett_ospf_lsa_mpls_link,
 894                 &ett_ospf_lsa_mpls_link_stlv
 895         };
 896
 897         proto_ospf = proto_register_protocol("Open Shortest Path First", "ospf");
 898  /*       proto_register_field_array(proto_ospf, hf, array_length(hf));*/
 899         proto_register_subtree_array(ett, array_length(ett));
 900 }
 901
 902 void
 903 proto_reg_handoff_ospf(void)
 904 {
 905         dissector_add("ip.proto", IP_PROTO_OSPF, dissect_ospf);
 906 }