ospfd/ospf_nsm.c

   1 /*
   2  * OSPF version 2  Neighbor State Machine
   3  * From RFC2328 [OSPF Version 2]
   4  * Copyright (C) 1999, 2000 Toshiaki Takada
   5  *
   6  * This file is part of GNU Zebra.
   7  *
   8  * GNU Zebra is free software; you can redistribute it and/or modify it
   9  * under the terms of the GNU General Public License as published by the
  10  * Free Software Foundation; either version 2, or (at your option) any
  11  * later version.
  12  *
  13  * GNU Zebra is distributed in the hope that it will be useful, but
  14  * WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16  * General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with GNU Zebra; see the file COPYING.  If not, write to the Free
  20  * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
  21  * 02111-1307, USA.
  22  */
  23
  24 #include <zebra.h>
  25
  26 #include "thread.h"
  27 #include "memory.h"
  28 #include "hash.h"
  29 #include "linklist.h"
  30 #include "prefix.h"
  31 #include "if.h"
  32 #include "table.h"
  33 #include "stream.h"
  34 #include "table.h"
  35 #include "log.h"
  36
  37 #include "ospfd/ospfd.h"
  38 #include "ospfd/ospf_interface.h"
  39 #include "ospfd/ospf_ism.h"
  40 #include "ospfd/ospf_asbr.h"
  41 #include "ospfd/ospf_lsa.h"
  42 #include "ospfd/ospf_lsdb.h"
  43 #include "ospfd/ospf_neighbor.h"
  44 #include "ospfd/ospf_nsm.h"
  45 #include "ospfd/ospf_network.h"
  46 #include "ospfd/ospf_packet.h"
  47 #include "ospfd/ospf_dump.h"
  48 #include "ospfd/ospf_flood.h"
  49 #include "ospfd/ospf_abr.h"
  50
  51 void nsm_reset_nbr (struct ospf_neighbor *);
  52
  53 \f
  54 /* OSPF NSM Timer functions. */
  55 int
  56 ospf_inactivity_timer (struct thread *thread)
  57 {
  58   struct ospf_neighbor *nbr;
  59
  60   nbr = THREAD_ARG (thread);
  61   nbr->t_inactivity = NULL;
  62
  63   if (IS_DEBUG_OSPF (nsm, NSM_TIMERS))
  64     zlog (NULL, LOG_DEBUG, "NSM[%s:%s]: Timer (Inactivity timer expire)",
  65           IF_NAME (nbr->oi), inet_ntoa (nbr->router_id));
  66
  67   OSPF_NSM_EVENT_SCHEDULE (nbr, NSM_InactivityTimer);
  68
  69   return 0;
  70 }
  71
  72 int
  73 ospf_db_desc_timer (struct thread *thread)
  74 {
  75   struct ospf_interface *oi;
  76   struct ospf_neighbor *nbr;
  77
  78   nbr = THREAD_ARG (thread);
  79   nbr->t_db_desc = NULL;
  80
  81   oi = nbr->oi;
  82
  83   if (IS_DEBUG_OSPF (nsm, NSM_TIMERS))
  84     zlog (NULL, LOG_INFO, "NSM[%s:%s]: Timer (DD Retransmit timer expire)",
  85           IF_NAME (nbr->oi), inet_ntoa (nbr->src));
  86
  87   /* resent last send DD packet. */
  88   assert (nbr->last_send);
  89   ospf_db_desc_resend (nbr);
  90
  91   /* DD Retransmit timer set. */
  92   OSPF_NSM_TIMER_ON (nbr->t_db_desc, ospf_db_desc_timer, nbr->v_db_desc);
  93
  94   return 0;
  95 }
  96
  97 /* Hook function called after ospf NSM event is occured. */
  98
  99 void
 100 nsm_timer_set (struct ospf_neighbor *nbr)
 101 {
 102   switch (nbr->state)
 103     {
 104     case NSM_Down:
 105       OSPF_NSM_TIMER_OFF (nbr->t_db_desc);
 106       OSPF_NSM_TIMER_OFF (nbr->t_ls_upd);
 107       break;
 108     case NSM_Attempt:
 109       OSPF_NSM_TIMER_OFF (nbr->t_db_desc);
 110       OSPF_NSM_TIMER_OFF (nbr->t_ls_upd);
 111       break;
 112     case NSM_Init:
 113       OSPF_NSM_TIMER_OFF (nbr->t_db_desc);
 114       OSPF_NSM_TIMER_OFF (nbr->t_ls_upd);
 115       break;
 116     case NSM_TwoWay:
 117       OSPF_NSM_TIMER_OFF (nbr->t_db_desc);
 118       OSPF_NSM_TIMER_OFF (nbr->t_ls_upd);
 119       break;
 120     case NSM_ExStart:
 121       OSPF_NSM_TIMER_ON (nbr->t_db_desc, ospf_db_desc_timer, nbr->v_db_desc);
 122       OSPF_NSM_TIMER_OFF (nbr->t_ls_upd);
 123       break;
 124     case NSM_Exchange:
 125       OSPF_NSM_TIMER_ON (nbr->t_ls_upd, ospf_ls_upd_timer, nbr->v_ls_upd);
 126       if (!IS_SET_DD_MS (nbr->dd_flags))
 127         OSPF_NSM_TIMER_OFF (nbr->t_db_desc);
 128       break;
 129     case NSM_Loading:
 130       OSPF_NSM_TIMER_OFF (nbr->t_db_desc);
 131       break;
 132     case NSM_Full:
 133       OSPF_NSM_TIMER_OFF (nbr->t_db_desc);
 134       break;
 135     default:
 136       OSPF_NSM_TIMER_OFF (nbr->t_db_desc);
 137       break;
 138     }
 139 }
 140
 141 \f
 142 /* OSPF NSM functions. */
 143 int
 144 nsm_ignore (struct ospf_neighbor *nbr)
 145 {
 146   if (IS_DEBUG_OSPF (nsm, NSM_EVENTS))
 147     zlog (NULL, LOG_INFO, "NSM[%s:%s]: nsm_ignore called",
 148           IF_NAME (nbr->oi), inet_ntoa (nbr->router_id));
 149
 150   return 0;
 151 }
 152
 153 int
 154 nsm_hello_received (struct ospf_neighbor *nbr)
 155 {
 156   /* Start or Restart Inactivity Timer. */
 157   OSPF_NSM_TIMER_OFF (nbr->t_inactivity);
 158
 159   OSPF_NSM_TIMER_ON (nbr->t_inactivity, ospf_inactivity_timer,
 160                      nbr->v_inactivity);
 161
 162   if (nbr->oi->type == OSPF_IFTYPE_NBMA && nbr->nbr_nbma)
 163     OSPF_POLL_TIMER_OFF (nbr->nbr_nbma->t_poll);
 164
 165   return 0;
 166 }
 167
 168 int
 169 nsm_start (struct ospf_neighbor *nbr)
 170 {
 171
 172   nsm_reset_nbr (nbr);
 173
 174   if (nbr->nbr_nbma)
 175       OSPF_POLL_TIMER_OFF (nbr->nbr_nbma->t_poll);
 176
 177   OSPF_NSM_TIMER_OFF (nbr->t_inactivity);
 178
 179   OSPF_NSM_TIMER_ON (nbr->t_inactivity, ospf_inactivity_timer,
 180                      nbr->v_inactivity);
 181
 182   return 0;
 183 }
 184
 185 int
 186 nsm_twoway_received (struct ospf_neighbor *nbr)
 187 {
 188   struct ospf_interface *oi;
 189   int next_state = NSM_TwoWay;
 190
 191   oi = nbr->oi;
 192
 193   /* These netowork types must be adjacency. */
 194   if (oi->type == OSPF_IFTYPE_POINTOPOINT ||
 195       oi->type == OSPF_IFTYPE_POINTOMULTIPOINT ||
 196       oi->type == OSPF_IFTYPE_VIRTUALLINK)
 197     next_state = NSM_ExStart;
 198
 199   /* Router itself is the DRouter or the BDRouter. */
 200   if (IPV4_ADDR_SAME (&oi->address->u.prefix4, &DR (oi)) ||
 201       IPV4_ADDR_SAME (&oi->address->u.prefix4, &BDR (oi)))
 202     next_state = NSM_ExStart;
 203
 204   /* Neighboring Router is the DRouter or the BDRouter. */
 205   if (IPV4_ADDR_SAME (&nbr->address.u.prefix4, &nbr->d_router) ||
 206       IPV4_ADDR_SAME (&nbr->address.u.prefix4, &nbr->bd_router))
 207     next_state = NSM_ExStart;
 208
 209   return next_state;
 210 }
 211
 212 int
 213 ospf_db_summary_count (struct ospf_neighbor *nbr)
 214 {
 215   return ospf_lsdb_count_all (&nbr->db_sum);
 216 }
 217
 218 int
 219 ospf_db_summary_isempty (struct ospf_neighbor *nbr)
 220 {
 221   return ospf_lsdb_isempty (&nbr->db_sum);
 222 }
 223
 224 int
 225 ospf_db_summary_add (struct ospf_lsa *lsa, void *v, int i)
 226 {
 227   struct ospf_neighbor *nbr = (struct ospf_neighbor *) v;
 228
 229   if (lsa == NULL)
 230     return 0;
 231
 232 #ifdef HAVE_OPAQUE_LSA
 233   switch (lsa->data->type)
 234     {
 235     case OSPF_OPAQUE_LINK_LSA:
 236       /* Exclude type-9 LSAs that does not have the same "oi" with "nbr". */
 237       if (lsa->oi != nbr->oi)
 238           return 0;
 239       break;
 240     case OSPF_OPAQUE_AREA_LSA:
 241       /*
 242        * It is assured by the caller function "nsm_negotiation_done()"
 243        * that every given LSA belongs to the same area with "nbr".
 244        */
 245       break;
 246     case OSPF_OPAQUE_AS_LSA:
 247     default:
 248       break;
 249     }
 250 #endif /* HAVE_OPAQUE_LSA */
 251
 252 #ifdef HAVE_NSSA
 253   /* Stay away from any Local Translated Type-7 LSAs */
 254   if (CHECK_FLAG (lsa->flags, OSPF_LSA_LOCAL_XLT))
 255     return 0;
 256 #endif /* HAVE_NSSA */
 257
 258   if (IS_LSA_MAXAGE (lsa))
 259     ospf_ls_retransmit_add (nbr, lsa);
 260   else
 261     ospf_lsdb_add (&nbr->db_sum, lsa);
 262
 263   return 0;
 264 }
 265
 266 void
 267 ospf_db_summary_clear (struct ospf_neighbor *nbr)
 268 {
 269   struct ospf_lsdb *lsdb;
 270   int i;
 271
 272   lsdb = &nbr->db_sum;
 273   for (i = OSPF_MIN_LSA; i < OSPF_MAX_LSA; i++)
 274     {
 275       struct route_table *table = lsdb->type[i].db;
 276       struct route_node *rn;
 277
 278       for (rn = route_top (table); rn; rn = route_next (rn))
 279         if (rn->info)
 280           ospf_lsdb_delete (&nbr->db_sum, rn->info);
 281     }
 282 }
 283
 284 \f
 285
 286 #ifdef HAVE_OPAQUE_LSA
 287 /* The area link state database consists of the router-LSAs,
 288    network-LSAs, summary-LSAs, and type-9/10 opaque-LSAs contained
 289                              ^^^^^^^^^^^^^^^^^^^^^^^^^^^
 290    in the area structure, along with the AS-external and type-11
 291                                                      ^^^^^^^^^^^
 292    opaque LSAs contained in the global structure.
 293    ^^^^^^
 294    AS-external and type-11 opaque LSAs are omitted from a virtual
 295                ^^^^^^^^^^^^^^^^^^
 296    neighbor's Database summary list. AS-external and type-11 opaque
 297                                                  ^^^^^^^^^^^^^^^^^^
 298    LSAs are omitted from the Database summary list if the area has
 299    been configured as a stub. */
 300 #else /* HAVE_OPAQUE_LSA */
 301 /* The area link state database consists of the router-LSAs,
 302    network-LSAs and summary-LSAs contained in the area structure,
 303    along with the AS-external- LSAs contained in the global structure.
 304    AS- external-LSAs are omitted from a virtual neighbor's Database
 305    summary list.  AS-external-LSAs are omitted from the Database
 306    summary list if the area has been configured as a stub. */
 307 #endif /* HAVE_OPAQUE_LSA */
 308 int
 309 nsm_negotiation_done (struct ospf_neighbor *nbr)
 310 {
 311   struct ospf_area *area;
 312
 313   area = nbr->oi->area;
 314
 315   foreach_lsa (ROUTER_LSDB (area), nbr, 0, ospf_db_summary_add);
 316   foreach_lsa (NETWORK_LSDB (area), nbr, 0, ospf_db_summary_add);
 317   foreach_lsa (SUMMARY_LSDB (area), nbr, 0, ospf_db_summary_add);
 318   foreach_lsa (ASBR_SUMMARY_LSDB (area), nbr, 0, ospf_db_summary_add);
 319
 320 #ifdef HAVE_OPAQUE_LSA
 321   /* Process only if the neighbor is opaque capable. */
 322   if (CHECK_FLAG (nbr->options, OSPF_OPTION_O))
 323     {
 324       foreach_lsa (OPAQUE_LINK_LSDB (area), nbr, 0, ospf_db_summary_add);
 325       foreach_lsa (OPAQUE_AREA_LSDB (area), nbr, 0, ospf_db_summary_add);
 326     }
 327 #endif /* HAVE_OPAQUE_LSA */
 328
 329   if (nbr->oi->type != OSPF_IFTYPE_VIRTUALLINK &&
 330       area->external_routing == OSPF_AREA_DEFAULT)
 331     foreach_lsa (EXTERNAL_LSDB (ospf_top), nbr, 0, ospf_db_summary_add);
 332
 333 #ifdef HAVE_OPAQUE_LSA
 334   if (CHECK_FLAG (nbr->options, OSPF_OPTION_O) &&
 335       (nbr->oi->type != OSPF_IFTYPE_VIRTUALLINK &&
 336        area->external_routing == OSPF_AREA_DEFAULT))
 337     foreach_lsa (OPAQUE_AS_LSDB (ospf_top),
 338                  nbr, 0, ospf_db_summary_add);
 339 #endif /* HAVE_OPAQUE_LSA */
 340
 341   /* OSPF_NSM_TIMER_OFF (nbr->t_db_desc); */
 342
 343   return 0;
 344 }
 345
 346 int
 347 nsm_exchange_done (struct ospf_neighbor *nbr)
 348 {
 349   struct ospf_interface *oi;
 350
 351   oi = nbr->oi;
 352
 353   if (ospf_ls_request_isempty (nbr))
 354     return NSM_Full;
 355
 356   /* Cancel dd retransmit timer. */
 357   /* OSPF_NSM_TIMER_OFF (nbr->t_db_desc); */
 358
 359   /* Send Link State Request. */
 360   ospf_ls_req_send (nbr);
 361
 362   return NSM_Loading;
 363 }
 364
 365 int
 366 nsm_bad_ls_req (struct ospf_neighbor *nbr)
 367 {
 368   /* Clear neighbor. */
 369   nsm_reset_nbr (nbr);
 370
 371   return 0;
 372 }
 373
 374 int
 375 nsm_adj_ok (struct ospf_neighbor *nbr)
 376 {
 377   struct ospf_interface *oi;
 378   int next_state;
 379   int flag = 0;
 380
 381   oi = nbr->oi;
 382   next_state = nbr->state;
 383
 384   /* These netowork types must be adjacency. */
 385   if (oi->type == OSPF_IFTYPE_POINTOPOINT ||
 386       oi->type == OSPF_IFTYPE_POINTOMULTIPOINT ||
 387       oi->type == OSPF_IFTYPE_VIRTUALLINK)
 388     flag = 1;
 389
 390   /* Router itself is the DRouter or the BDRouter. */
 391   if (IPV4_ADDR_SAME (&oi->address->u.prefix4, &DR (oi)) ||
 392       IPV4_ADDR_SAME (&oi->address->u.prefix4, &BDR (oi)))
 393     flag = 1;
 394
 395   if (IPV4_ADDR_SAME (&nbr->address.u.prefix4, &DR (oi)) ||
 396       IPV4_ADDR_SAME (&nbr->address.u.prefix4, &BDR (oi)))
 397     flag = 1;
 398
 399   if (nbr->state == NSM_TwoWay && flag == 1)
 400     next_state = NSM_ExStart;
 401   else if (nbr->state >= NSM_ExStart && flag == 0)
 402     next_state = NSM_TwoWay;
 403
 404   return next_state;
 405 }
 406
 407 int
 408 nsm_seq_number_mismatch (struct ospf_neighbor *nbr)
 409 {
 410   /* Clear neighbor. */
 411   nsm_reset_nbr (nbr);
 412
 413   return 0;
 414 }
 415
 416 int
 417 nsm_oneway_received (struct ospf_neighbor *nbr)
 418 {
 419   /* Clear neighbor. */
 420   nsm_reset_nbr (nbr);
 421
 422   return 0;
 423 }
 424
 425 void
 426 nsm_reset_nbr (struct ospf_neighbor *nbr)
 427 {
 428   /* Clear Database Summary list. */
 429   if (!ospf_db_summary_isempty (nbr))
 430     ospf_db_summary_clear (nbr);
 431
 432   /* Clear Link State Request list. */
 433   if (!ospf_ls_request_isempty (nbr))
 434     ospf_ls_request_delete_all (nbr);
 435
 436   /* Clear Link State Retransmission list. */
 437   if (!ospf_ls_retransmit_isempty (nbr))
 438     ospf_ls_retransmit_clear (nbr);
 439
 440   /* Cancel thread. */
 441   OSPF_NSM_TIMER_OFF (nbr->t_db_desc);
 442   OSPF_NSM_TIMER_OFF (nbr->t_ls_req);
 443   OSPF_NSM_TIMER_OFF (nbr->t_ls_upd);
 444   OSPF_NSM_TIMER_OFF (nbr->t_hello_reply);
 445
 446 #ifdef HAVE_OPAQUE_LSA
 447   if (CHECK_FLAG (nbr->options, OSPF_OPTION_O))
 448     UNSET_FLAG (nbr->options, OSPF_OPTION_O);
 449 #endif /* HAVE_OPAQUE_LSA */
 450 }
 451
 452 int
 453 nsm_kill_nbr (struct ospf_neighbor *nbr)
 454 {
 455   /* call it here because we cannot call it from ospf_nsm_event */
 456   nsm_change_state (nbr, NSM_Down);
 457
 458   /* Reset neighbor. */
 459   nsm_reset_nbr (nbr);
 460
 461   if (nbr->oi->type == OSPF_IFTYPE_NBMA && nbr->nbr_nbma != NULL)
 462     {
 463       struct ospf_nbr_nbma *nbr_nbma = nbr->nbr_nbma;
 464
 465       nbr_nbma->nbr = NULL;
 466       nbr_nbma->state_change = nbr->state_change;
 467
 468       nbr->nbr_nbma = NULL;
 469
 470       OSPF_POLL_TIMER_ON (nbr_nbma->t_poll, ospf_poll_timer,
 471                           nbr_nbma->v_poll);
 472
 473       if (IS_DEBUG_OSPF (nsm, NSM_EVENTS))
 474         zlog_info ("NSM[%s:%s]: Down (PollIntervalTimer scheduled)",
 475                    IF_NAME (nbr->oi), inet_ntoa (nbr->address.u.prefix4));
 476     }
 477
 478   /* Delete neighbor from interface. */
 479   ospf_nbr_delete (nbr);
 480
 481   return 0;
 482 }
 483
 484 int
 485 nsm_inactivity_timer (struct ospf_neighbor *nbr)
 486 {
 487   /* Kill neighbor. */
 488   nsm_kill_nbr (nbr);
 489
 490   return 0;
 491 }
 492
 493 int
 494 nsm_ll_down (struct ospf_neighbor *nbr)
 495 {
 496   /* Reset neighbor. */
 497   /*nsm_reset_nbr (nbr);*/
 498
 499   /* Kill neighbor. */
 500   nsm_kill_nbr (nbr);
 501
 502   return 0;
 503 }
 504
 505 /* Neighbor State Machine */
 506 struct {
 507   int (*func) ();
 508   int next_state;
 509 } NSM [OSPF_NSM_STATE_MAX][OSPF_NSM_EVENT_MAX] =
 510 {
 511   {
 512     /* DependUpon: dummy state. */
 513     { nsm_ignore,              NSM_DependUpon }, /* NoEvent           */
 514     { nsm_ignore,              NSM_DependUpon }, /* HelloReceived     */
 515     { nsm_ignore,              NSM_DependUpon }, /* Start             */
 516     { nsm_ignore,              NSM_DependUpon }, /* 2-WayReceived     */
 517     { nsm_ignore,              NSM_DependUpon }, /* NegotiationDone   */
 518     { nsm_ignore,              NSM_DependUpon }, /* ExchangeDone      */
 519     { nsm_ignore,              NSM_DependUpon }, /* BadLSReq          */
 520     { nsm_ignore,              NSM_DependUpon }, /* LoadingDone       */
 521     { nsm_ignore,              NSM_DependUpon }, /* AdjOK?            */
 522     { nsm_ignore,              NSM_DependUpon }, /* SeqNumberMismatch */
 523     { nsm_ignore,              NSM_DependUpon }, /* 1-WayReceived     */
 524     { nsm_ignore,              NSM_DependUpon }, /* KillNbr           */
 525     { nsm_ignore,              NSM_DependUpon }, /* InactivityTimer   */
 526     { nsm_ignore,              NSM_DependUpon }, /* LLDown            */
 527   },
 528   {
 529     /* Down: */
 530     { nsm_ignore,              NSM_DependUpon }, /* NoEvent           */
 531     { nsm_hello_received,      NSM_Init       }, /* HelloReceived     */
 532     { nsm_start,               NSM_Attempt    }, /* Start             */
 533     { nsm_ignore,              NSM_Down       }, /* 2-WayReceived     */
 534     { nsm_ignore,              NSM_Down       }, /* NegotiationDone   */
 535     { nsm_ignore,              NSM_Down       }, /* ExchangeDone      */
 536     { nsm_ignore,              NSM_Down       }, /* BadLSReq          */
 537     { nsm_ignore,              NSM_Down       }, /* LoadingDone       */
 538     { nsm_ignore,              NSM_Down       }, /* AdjOK?            */
 539     { nsm_ignore,              NSM_Down       }, /* SeqNumberMismatch */
 540     { nsm_ignore,              NSM_Down       }, /* 1-WayReceived     */
 541     { nsm_kill_nbr,            NSM_Down       }, /* KillNbr           */
 542     { nsm_inactivity_timer,    NSM_Down       }, /* InactivityTimer   */
 543     { nsm_ll_down,             NSM_Down       }, /* LLDown            */
 544   },
 545   {
 546     /* Attempt: */
 547     { nsm_ignore,              NSM_DependUpon }, /* NoEvent           */
 548     { nsm_hello_received,      NSM_Init       }, /* HelloReceived     */
 549     { nsm_ignore,              NSM_Attempt    }, /* Start             */
 550     { nsm_ignore,              NSM_Attempt    }, /* 2-WayReceived     */
 551     { nsm_ignore,              NSM_Attempt    }, /* NegotiationDone   */
 552     { nsm_ignore,              NSM_Attempt    }, /* ExchangeDone      */
 553     { nsm_ignore,              NSM_Attempt    }, /* BadLSReq          */
 554     { nsm_ignore,              NSM_Attempt    }, /* LoadingDone       */
 555     { nsm_ignore,              NSM_Attempt    }, /* AdjOK?            */
 556     { nsm_ignore,              NSM_Attempt    }, /* SeqNumberMismatch */
 557     { nsm_ignore,              NSM_Attempt    }, /* 1-WayReceived     */
 558     { nsm_kill_nbr,            NSM_Down       }, /* KillNbr           */
 559     { nsm_inactivity_timer,    NSM_Down       }, /* InactivityTimer   */
 560     { nsm_ll_down,             NSM_Down       }, /* LLDown            */
 561   },
 562   {
 563     /* Init: */
 564     { nsm_ignore,              NSM_DependUpon }, /* NoEvent           */
 565     { nsm_hello_received,      NSM_Init       }, /* HelloReceived     */
 566     { nsm_ignore,              NSM_Init       }, /* Start             */
 567     { nsm_twoway_received,     NSM_DependUpon }, /* 2-WayReceived     */
 568     { nsm_ignore,              NSM_Init       }, /* NegotiationDone   */
 569     { nsm_ignore,              NSM_Init       }, /* ExchangeDone      */
 570     { nsm_ignore,              NSM_Init       }, /* BadLSReq          */
 571     { nsm_ignore,              NSM_Init       }, /* LoadingDone       */
 572     { nsm_ignore,              NSM_Init       }, /* AdjOK?            */
 573     { nsm_ignore,              NSM_Init       }, /* SeqNumberMismatch */
 574     { nsm_ignore,              NSM_Init       }, /* 1-WayReceived     */
 575     { nsm_kill_nbr,            NSM_Down       }, /* KillNbr           */
 576     { nsm_inactivity_timer,    NSM_Down       }, /* InactivityTimer   */
 577     { nsm_ll_down,             NSM_Down       }, /* LLDown            */
 578   },
 579   {
 580     /* 2-Way: */
 581     { nsm_ignore,              NSM_DependUpon }, /* NoEvent           */
 582     { nsm_hello_received,      NSM_TwoWay     }, /* HelloReceived     */
 583     { nsm_ignore,              NSM_TwoWay     }, /* Start             */
 584     { nsm_ignore,              NSM_TwoWay     }, /* 2-WayReceived     */
 585     { nsm_ignore,              NSM_TwoWay     }, /* NegotiationDone   */
 586     { nsm_ignore,              NSM_TwoWay     }, /* ExchangeDone      */
 587     { nsm_ignore,              NSM_TwoWay     }, /* BadLSReq          */
 588     { nsm_ignore,              NSM_TwoWay     }, /* LoadingDone       */
 589     { nsm_adj_ok,              NSM_DependUpon }, /* AdjOK?            */
 590     { nsm_ignore,              NSM_TwoWay     }, /* SeqNumberMismatch */
 591     { nsm_oneway_received,     NSM_Init       }, /* 1-WayReceived     */
 592     { nsm_kill_nbr,            NSM_Down       }, /* KillNbr           */
 593     { nsm_inactivity_timer,    NSM_Down       }, /* InactivityTimer   */
 594     { nsm_ll_down,             NSM_Down       }, /* LLDown            */
 595   },
 596   {
 597     /* ExStart: */
 598     { nsm_ignore,              NSM_DependUpon }, /* NoEvent           */
 599     { nsm_hello_received,      NSM_ExStart    }, /* HelloReceived     */
 600     { nsm_ignore,              NSM_ExStart    }, /* Start             */
 601     { nsm_ignore,              NSM_ExStart    }, /* 2-WayReceived     */
 602     { nsm_negotiation_done,    NSM_Exchange   }, /* NegotiationDone   */
 603     { nsm_ignore,              NSM_ExStart    }, /* ExchangeDone      */
 604     { nsm_ignore,              NSM_ExStart    }, /* BadLSReq          */
 605     { nsm_ignore,              NSM_ExStart    }, /* LoadingDone       */
 606     { nsm_adj_ok,              NSM_DependUpon }, /* AdjOK?            */
 607     { nsm_ignore,              NSM_ExStart    }, /* SeqNumberMismatch */
 608     { nsm_oneway_received,     NSM_Init       }, /* 1-WayReceived     */
 609     { nsm_kill_nbr,            NSM_Down       }, /* KillNbr           */
 610     { nsm_inactivity_timer,    NSM_Down       }, /* InactivityTimer   */
 611     { nsm_ll_down,             NSM_Down       }, /* LLDown            */
 612   },
 613   {
 614     /* Exchange: */
 615     { nsm_ignore,              NSM_DependUpon }, /* NoEvent           */
 616     { nsm_hello_received,      NSM_Exchange   }, /* HelloReceived     */
 617     { nsm_ignore,              NSM_Exchange   }, /* Start             */
 618     { nsm_ignore,              NSM_Exchange   }, /* 2-WayReceived     */
 619     { nsm_ignore,              NSM_Exchange   }, /* NegotiationDone   */
 620     { nsm_exchange_done,       NSM_DependUpon }, /* ExchangeDone      */
 621     { nsm_bad_ls_req,          NSM_ExStart    }, /* BadLSReq          */
 622     { nsm_ignore,              NSM_Exchange   }, /* LoadingDone       */
 623     { nsm_adj_ok,              NSM_DependUpon }, /* AdjOK?            */
 624     { nsm_seq_number_mismatch, NSM_ExStart    }, /* SeqNumberMismatch */
 625     { nsm_oneway_received,     NSM_Init       }, /* 1-WayReceived     */
 626     { nsm_kill_nbr,            NSM_Down       }, /* KillNbr           */
 627     { nsm_inactivity_timer,    NSM_Down       }, /* InactivityTimer   */
 628     { nsm_ll_down,             NSM_Down       }, /* LLDown            */
 629   },
 630   {
 631     /* Loading: */
 632     { nsm_ignore,              NSM_DependUpon }, /* NoEvent           */
 633     { nsm_hello_received,      NSM_Loading    }, /* HelloReceived     */
 634     { nsm_ignore,              NSM_Loading    }, /* Start             */
 635     { nsm_ignore,              NSM_Loading    }, /* 2-WayReceived     */
 636     { nsm_ignore,              NSM_Loading    }, /* NegotiationDone   */
 637     { nsm_ignore,              NSM_Loading    }, /* ExchangeDone      */
 638     { nsm_bad_ls_req,          NSM_ExStart    }, /* BadLSReq          */
 639     { nsm_ignore,              NSM_Full       }, /* LoadingDone       */
 640     { nsm_adj_ok,              NSM_DependUpon }, /* AdjOK?            */
 641     { nsm_seq_number_mismatch, NSM_ExStart    }, /* SeqNumberMismatch */
 642     { nsm_oneway_received,     NSM_Init       }, /* 1-WayReceived     */
 643     { nsm_kill_nbr,            NSM_Down       }, /* KillNbr           */
 644     { nsm_inactivity_timer,    NSM_Down       }, /* InactivityTimer   */
 645     { nsm_ll_down,             NSM_Down       }, /* LLDown            */
 646   },
 647   { /* Full: */
 648     { nsm_ignore,              NSM_DependUpon }, /* NoEvent           */
 649     { nsm_hello_received,      NSM_Full       }, /* HelloReceived     */
 650     { nsm_ignore,              NSM_Full       }, /* Start             */
 651     { nsm_ignore,              NSM_Full       }, /* 2-WayReceived     */
 652     { nsm_ignore,              NSM_Full       }, /* NegotiationDone   */
 653     { nsm_ignore,              NSM_Full       }, /* ExchangeDone      */
 654     { nsm_bad_ls_req,          NSM_ExStart    }, /* BadLSReq          */
 655     { nsm_ignore,              NSM_Full       }, /* LoadingDone       */
 656     { nsm_adj_ok,              NSM_DependUpon }, /* AdjOK?            */
 657     { nsm_seq_number_mismatch, NSM_ExStart    }, /* SeqNumberMismatch */
 658     { nsm_oneway_received,     NSM_Init       }, /* 1-WayReceived     */
 659     { nsm_kill_nbr,            NSM_Down       }, /* KillNbr           */
 660     { nsm_inactivity_timer,    NSM_Down       }, /* InactivityTimer   */
 661     { nsm_ll_down,             NSM_Down       }, /* LLDown            */
 662   },
 663 };
 664
 665 static char *ospf_nsm_event_str[] =
 666 {
 667   "NoEvent",
 668   "HelloReceived",
 669   "Start",
 670   "2-WayReceived",
 671   "NegotiationDone",
 672   "ExchangeDone",
 673   "BadLSReq",
 674   "LoadingDone",
 675   "AdjOK?",
 676   "SeqNumberMismatch",
 677   "1-WayReceived",
 678   "KillNbr",
 679   "InactivityTimer",
 680   "LLDown",
 681 };
 682
 683 void
 684 nsm_change_state (struct ospf_neighbor *nbr, int state)
 685 {
 686   struct ospf_interface *oi;
 687   struct ospf_area *vl_area = NULL;
 688   u_char old_state;
 689   int x;
 690   int force = 1;
 691
 692   /* Logging change of status. */
 693   if (IS_DEBUG_OSPF (nsm, NSM_STATUS))
 694     zlog_info ("NSM[%s:%s]: State change %s -> %s",
 695                IF_NAME (nbr->oi), inet_ntoa (nbr->router_id),
 696                LOOKUP (ospf_nsm_state_msg, nbr->state),
 697                LOOKUP (ospf_nsm_state_msg, state));
 698
 699   /* Preserve old status. */
 700   old_state = nbr->state;
 701
 702   /* Change to new status. */
 703   nbr->state = state;
 704
 705   /* Statistics. */
 706   nbr->state_change++;
 707
 708   oi = nbr->oi;
 709
 710   if (oi->type == OSPF_IFTYPE_VIRTUALLINK)
 711     vl_area = ospf_area_lookup_by_area_id (oi->vl_data->vl_area_id);
 712
 713   /* One of the neighboring routers changes to/from the FULL state. */
 714   if ((old_state != NSM_Full && state == NSM_Full) ||
 715       (old_state == NSM_Full && state != NSM_Full))
 716     {
 717       if (state == NSM_Full)
 718         {
 719           oi->full_nbrs++;
 720           oi->area->full_nbrs++;
 721
 722           ospf_check_abr_status ();
 723
 724           if (oi->type == OSPF_IFTYPE_VIRTUALLINK && vl_area)
 725             if (++vl_area->full_vls == 1)
 726               ospf_schedule_abr_task ();
 727
 728           /* kevinm: refresh any redistributions */
 729           for (x = ZEBRA_ROUTE_SYSTEM; x < ZEBRA_ROUTE_MAX; x++) {
 730             if (x == ZEBRA_ROUTE_OSPF || x == ZEBRA_ROUTE_OSPF6)
 731               continue;
 732             ospf_external_lsa_refresh_type(x, force);
 733           }
 734
 735         }
 736       else
 737         {
 738           oi->full_nbrs--;
 739           oi->area->full_nbrs--;
 740
 741           ospf_check_abr_status ();
 742
 743           if (oi->type == OSPF_IFTYPE_VIRTUALLINK && vl_area)
 744             if (vl_area->full_vls > 0)
 745               if (--vl_area->full_vls == 0)
 746                 ospf_schedule_abr_task ();
 747
 748           /* clear neighbor retransmit list */
 749           if (!ospf_ls_retransmit_isempty (nbr))
 750             ospf_ls_retransmit_clear (nbr);
 751         }
 752
 753       zlog_info ("nsm_change_state(): "
 754                  "scheduling new router-LSA origination");
 755
 756       ospf_router_lsa_timer_add (oi->area);
 757
 758       if (oi->type == OSPF_IFTYPE_VIRTUALLINK)
 759         {
 760           struct ospf_area *vl_area =
 761             ospf_area_lookup_by_area_id (oi->vl_data->vl_area_id);
 762
 763           if (vl_area)
 764             ospf_router_lsa_timer_add (vl_area);
 765         }
 766
 767       /* Originate network-LSA. */
 768       if (oi->state == ISM_DR)
 769         {
 770           if (oi->network_lsa_self && oi->full_nbrs == 0)
 771             {
 772               ospf_lsa_flush_area (oi->network_lsa_self, oi->area);
 773               ospf_lsa_unlock (oi->network_lsa_self);
 774               oi->network_lsa_self = NULL;
 775               OSPF_TIMER_OFF (oi->t_network_lsa_self);
 776             }
 777           else
 778             ospf_network_lsa_timer_add (oi);
 779         }
 780     }
 781
 782 #ifdef HAVE_OPAQUE_LSA
 783   ospf_opaque_nsm_change (nbr, old_state);
 784 #endif /* HAVE_OPAQUE_LSA */
 785
 786   /* Start DD exchange protocol */
 787   if (state == NSM_ExStart)
 788     {
 789       if (nbr->dd_seqnum == 0)
 790         nbr->dd_seqnum = time (NULL);
 791       else
 792         nbr->dd_seqnum++;
 793
 794       nbr->dd_flags = OSPF_DD_FLAG_I|OSPF_DD_FLAG_M|OSPF_DD_FLAG_MS;
 795       ospf_db_desc_send (nbr);
 796     }
 797
 798   /* clear cryptographic sequence number */
 799   if (state == NSM_Down)
 800     nbr->crypt_seqnum = 0;
 801
 802   /* Generete NeighborChange ISM event. */
 803 #ifdef BUGGY_ISM_TRANSITION
 804   if ((old_state < NSM_TwoWay && state >= NSM_TwoWay) ||
 805       (old_state >= NSM_TwoWay && state < NSM_TwoWay))
 806     OSPF_ISM_EVENT_EXECUTE (oi, ISM_NeighborChange);
 807 #else /* BUGGY_ISM_TRANSITION */
 808   switch (oi->state) {
 809   case ISM_DROther:
 810   case ISM_Backup:
 811   case ISM_DR:
 812     if ((old_state < NSM_TwoWay && state >= NSM_TwoWay) ||
 813         (old_state >= NSM_TwoWay && state < NSM_TwoWay))
 814       OSPF_ISM_EVENT_EXECUTE (oi, ISM_NeighborChange);
 815     break;
 816   default:
 817     /* ISM_PointToPoint -> ISM_Down, ISM_Loopback -> ISM_Down, etc. */
 818     break;
 819   }
 820 #endif /* BUGGY_ISM_TRANSITION */
 821
 822   /* Performance hack. Send hello immideately when some neighbor enter
 823      Init state.  This whay we decrease neighbor discovery time. Gleb.*/
 824   if (state == NSM_Init)
 825     {
 826       OSPF_ISM_TIMER_OFF (oi->t_hello);
 827       OSPF_ISM_TIMER_ON (oi->t_hello, ospf_hello_timer, 1);
 828     }
 829
 830   /* Preserve old status? */
 831 }
 832
 833 /* Execute NSM event process. */
 834 int
 835 ospf_nsm_event (struct thread *thread)
 836 {
 837   int event;
 838   int next_state;
 839   struct ospf_neighbor *nbr;
 840   struct in_addr router_id;
 841   int old_state;
 842   struct ospf_interface *oi;
 843
 844   nbr = THREAD_ARG (thread);
 845   event = THREAD_VAL (thread);
 846   router_id = nbr->router_id;
 847
 848   old_state = nbr->state;
 849   oi = nbr->oi ;
 850
 851   /* Call function. */
 852   next_state = (*(NSM [nbr->state][event].func))(nbr);
 853
 854   /* When event is NSM_KillNbr or InactivityTimer, the neighbor is
 855      deleted. */
 856   if (event == NSM_KillNbr || event == NSM_InactivityTimer)
 857     {
 858       if (IS_DEBUG_OSPF (nsm, NSM_EVENTS))
 859         zlog_info ("NSM[%s:%s]: neighbor deleted",
 860                    IF_NAME (oi), inet_ntoa (router_id));
 861
 862       /* Timers are canceled in ospf_nbr_free, moreover we cannot call
 863          nsm_timer_set here because nbr is freed already!!!*/
 864       /*nsm_timer_set (nbr);*/
 865
 866       return 0;
 867     }
 868
 869   if (! next_state)
 870     next_state = NSM [nbr->state][event].next_state;
 871
 872   if (IS_DEBUG_OSPF (nsm, NSM_EVENTS))
 873     zlog_info ("NSM[%s:%s]: %s (%s)", IF_NAME (oi),
 874                inet_ntoa (nbr->router_id),
 875                LOOKUP (ospf_nsm_state_msg, nbr->state),
 876                ospf_nsm_event_str [event]);
 877
 878   /* If state is changed. */
 879   if (next_state != nbr->state)
 880     nsm_change_state (nbr, next_state);
 881
 882   /* Make sure timer is set. */
 883   nsm_timer_set (nbr);
 884
 885   return 0;
 886 }
 887
 888 /* Check loading state. */
 889 void
 890 ospf_check_nbr_loading (struct ospf_neighbor *nbr)
 891 {
 892   if (nbr->state == NSM_Loading)
 893     {
 894       if (ospf_ls_request_isempty (nbr))
 895         OSPF_NSM_EVENT_SCHEDULE (nbr, NSM_LoadingDone);
 896       else if (nbr->ls_req_last == NULL)
 897         ospf_ls_req_event (nbr);
 898     }
 899 }