ospfd/ospf_neighbor.c

   1 /*
   2  * OSPF Neighbor functions.
   3  * Copyright (C) 1999, 2000 Toshiaki Takada
   4  *
   5  * This file is part of GNU Zebra.
   6  *
   7  * GNU Zebra is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published
   9  * by the Free Software Foundation; either version 2, or (at your
  10  * option) any later version.
  11  *
  12  * GNU Zebra is distributed in the hope that it will be useful, but
  13  * WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with GNU Zebra; see the file COPYING.  If not, write to the
  19  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  20  * Boston, MA 02111-1307, USA.
  21  */
  22
  23 #include <zebra.h>
  24
  25 #include "linklist.h"
  26 #include "prefix.h"
  27 #include "memory.h"
  28 #include "command.h"
  29 #include "thread.h"
  30 #include "stream.h"
  31 #include "table.h"
  32 #include "log.h"
  33 #include "json.h"
  34
  35 #include "ospfd/ospfd.h"
  36 #include "ospfd/ospf_interface.h"
  37 #include "ospfd/ospf_asbr.h"
  38 #include "ospfd/ospf_lsa.h"
  39 #include "ospfd/ospf_lsdb.h"
  40 #include "ospfd/ospf_neighbor.h"
  41 #include "ospfd/ospf_nsm.h"
  42 #include "ospfd/ospf_packet.h"
  43 #include "ospfd/ospf_network.h"
  44 #include "ospfd/ospf_flood.h"
  45 #include "ospfd/ospf_dump.h"
  46 #include "ospfd/ospf_bfd.h"
  47
  48 /* Fill in the the 'key' as appropriate to retrieve the entry for nbr
  49  * from the ospf_interface's nbrs table. Indexed by interface address
  50  * for all cases except Virtual-link interfaces, where neighbours are
  51  * indexed by router-ID instead.
  52  */
  53 static void
  54 ospf_nbr_key (struct ospf_interface *oi, struct ospf_neighbor *nbr,
  55               struct prefix *key)
  56 {
  57   key->family = AF_INET;
  58   key->prefixlen = IPV4_MAX_BITLEN;
  59
  60   /* vlinks are indexed by router-id */
  61   if (oi->type == OSPF_IFTYPE_VIRTUALLINK)
  62     key->u.prefix4 = nbr->router_id;
  63   else
  64     key->u.prefix4 = nbr->src;
  65   return;
  66 }
  67
  68 struct ospf_neighbor *
  69 ospf_nbr_new (struct ospf_interface *oi)
  70 {
  71   struct ospf_neighbor *nbr;
  72
  73   /* Allcate new neighbor. */
  74   nbr = XCALLOC (MTYPE_OSPF_NEIGHBOR, sizeof (struct ospf_neighbor));
  75
  76   /* Relate neighbor to the interface. */
  77   nbr->oi = oi;
  78
  79   /* Set default values. */
  80   nbr->state = NSM_Down;
  81
  82   /* Set inheritance values. */
  83   nbr->v_inactivity = OSPF_IF_PARAM (oi, v_wait);
  84   nbr->v_db_desc = OSPF_IF_PARAM (oi, retransmit_interval);
  85   nbr->v_ls_req = OSPF_IF_PARAM (oi, retransmit_interval);
  86   nbr->v_ls_upd = OSPF_IF_PARAM (oi, retransmit_interval);
  87   nbr->priority = -1;
  88
  89   /* DD flags. */
  90   nbr->dd_flags = OSPF_DD_FLAG_MS|OSPF_DD_FLAG_M|OSPF_DD_FLAG_I;
  91
  92   /* Last received and sent DD. */
  93   nbr->last_send = NULL;
  94
  95   nbr->nbr_nbma = NULL;
  96
  97   ospf_lsdb_init (&nbr->db_sum);
  98   ospf_lsdb_init (&nbr->ls_rxmt);
  99   ospf_lsdb_init (&nbr->ls_req);
 100
 101   nbr->crypt_seqnum = 0;
 102
 103   ospf_bfd_info_nbr_create(oi, nbr);
 104   return nbr;
 105 }
 106
 107 void
 108 ospf_nbr_free (struct ospf_neighbor *nbr)
 109 {
 110   /* Free DB summary list. */
 111   if (ospf_db_summary_count (nbr))
 112     ospf_db_summary_clear (nbr);
 113     /* ospf_db_summary_delete_all (nbr); */
 114
 115   /* Free ls request list. */
 116   if (ospf_ls_request_count (nbr))
 117     ospf_ls_request_delete_all (nbr);
 118
 119   /* Free retransmit list. */
 120   if (ospf_ls_retransmit_count (nbr))
 121     ospf_ls_retransmit_clear (nbr);
 122
 123   /* Cleanup LSDBs. */
 124   ospf_lsdb_cleanup (&nbr->db_sum);
 125   ospf_lsdb_cleanup (&nbr->ls_req);
 126   ospf_lsdb_cleanup (&nbr->ls_rxmt);
 127
 128   /* Clear last send packet. */
 129   if (nbr->last_send)
 130     ospf_packet_free (nbr->last_send);
 131
 132   if (nbr->nbr_nbma)
 133     {
 134       nbr->nbr_nbma->nbr = NULL;
 135       nbr->nbr_nbma = NULL;
 136     }
 137
 138   /* Cancel all timers. */
 139   OSPF_NSM_TIMER_OFF (nbr->t_inactivity);
 140   OSPF_NSM_TIMER_OFF (nbr->t_db_desc);
 141   OSPF_NSM_TIMER_OFF (nbr->t_ls_req);
 142   OSPF_NSM_TIMER_OFF (nbr->t_ls_upd);
 143
 144   /* Cancel all events. *//* Thread lookup cost would be negligible. */
 145   thread_cancel_event (master, nbr);
 146
 147   ospf_bfd_info_free(&nbr->bfd_info);
 148   XFREE (MTYPE_OSPF_NEIGHBOR, nbr);
 149 }
 150
 151 /* Delete specified OSPF neighbor from interface. */
 152 void
 153 ospf_nbr_delete (struct ospf_neighbor *nbr)
 154 {
 155   struct ospf_interface *oi;
 156   struct route_node *rn;
 157   struct prefix p;
 158
 159   oi = nbr->oi;
 160
 161   /* get appropriate prefix 'key' */
 162   ospf_nbr_key (oi, nbr, &p);
 163
 164   rn = route_node_lookup (oi->nbrs, &p);
 165   if (rn)
 166     {
 167       /* If lookup for a NBR succeeds, the leaf route_node could
 168        * only exist because there is (or was) a nbr there.
 169        * If the nbr was deleted, the leaf route_node should have
 170        * lost its last refcount too, and be deleted.
 171        * Therefore a looked-up leaf route_node in nbrs table
 172        * should never have NULL info.
 173        */
 174       assert (rn->info);
 175
 176       if (rn->info)
 177         {
 178           rn->info = NULL;
 179           route_unlock_node (rn);
 180         }
 181       else
 182         zlog_info ("Can't find neighbor %s in the interface %s",
 183                    inet_ntoa (nbr->src), IF_NAME (oi));
 184
 185       route_unlock_node (rn);
 186     }
 187
 188   /* Free ospf_neighbor structure. */
 189   ospf_nbr_free (nbr);
 190 }
 191
 192 /* Check myself is in the neighbor list. */
 193 int
 194 ospf_nbr_bidirectional (struct in_addr *router_id,
 195                         struct in_addr *neighbors, int size)
 196 {
 197   int i;
 198   int max;
 199
 200   max = size / sizeof (struct in_addr);
 201
 202   for (i = 0; i < max; i ++)
 203     if (IPV4_ADDR_SAME (router_id, &neighbors[i]))
 204       return 1;
 205
 206   return 0;
 207 }
 208
 209 /* Add self to nbr list. */
 210 void
 211 ospf_nbr_add_self (struct ospf_interface *oi)
 212 {
 213   struct prefix p;
 214   struct route_node *rn;
 215
 216   /* Initial state */
 217   oi->nbr_self->address = *oi->address;
 218   oi->nbr_self->priority = OSPF_IF_PARAM (oi, priority);
 219   oi->nbr_self->router_id = oi->ospf->router_id;
 220   oi->nbr_self->src = oi->address->u.prefix4;
 221   oi->nbr_self->state = NSM_TwoWay;
 222
 223   switch (oi->area->external_routing)
 224     {
 225       case OSPF_AREA_DEFAULT:
 226         SET_FLAG (oi->nbr_self->options, OSPF_OPTION_E);
 227         break;
 228       case OSPF_AREA_STUB:
 229         UNSET_FLAG (oi->nbr_self->options, OSPF_OPTION_E);
 230         break;
 231       case OSPF_AREA_NSSA:
 232         UNSET_FLAG (oi->nbr_self->options, OSPF_OPTION_E);
 233         SET_FLAG (oi->nbr_self->options, OSPF_OPTION_NP);
 234         break;
 235     }
 236
 237   /* Add nbr_self to nbrs table */
 238   ospf_nbr_key (oi, oi->nbr_self, &p);
 239
 240   rn = route_node_get (oi->nbrs, &p);
 241   if (rn->info)
 242     {
 243       /* There is already pseudo neighbor. */
 244       assert (oi->nbr_self == rn->info);
 245       route_unlock_node (rn);
 246     }
 247   else
 248     rn->info = oi->nbr_self;
 249 }
 250
 251 /* Get neighbor count by status.
 252    Specify status = 0, get all neighbor other than myself. */
 253 int
 254 ospf_nbr_count (struct ospf_interface *oi, int state)
 255 {
 256   struct ospf_neighbor *nbr;
 257   struct route_node *rn;
 258   int count = 0;
 259
 260   for (rn = route_top (oi->nbrs); rn; rn = route_next (rn))
 261     if ((nbr = rn->info))
 262       if (!IPV4_ADDR_SAME (&nbr->router_id, &oi->ospf->router_id))
 263         if (state == 0 || nbr->state == state)
 264           count++;
 265
 266   return count;
 267 }
 268
 269 #ifdef HAVE_OPAQUE_LSA
 270 int
 271 ospf_nbr_count_opaque_capable (struct ospf_interface *oi)
 272 {
 273   struct ospf_neighbor *nbr;
 274   struct route_node *rn;
 275   int count = 0;
 276
 277   for (rn = route_top (oi->nbrs); rn; rn = route_next (rn))
 278     if ((nbr = rn->info))
 279       if (!IPV4_ADDR_SAME (&nbr->router_id, &oi->ospf->router_id))
 280         if (nbr->state == NSM_Full)
 281           if (CHECK_FLAG (nbr->options, OSPF_OPTION_O))
 282             count++;
 283
 284   return count;
 285 }
 286 #endif /* HAVE_OPAQUE_LSA */
 287
 288 /* lookup nbr by address - use this only if you know you must
 289  * otherwise use the ospf_nbr_lookup() wrapper, which deals
 290  * with virtual link neighbours
 291  */
 292 struct ospf_neighbor *
 293 ospf_nbr_lookup_by_addr (struct route_table *nbrs,
 294                          struct in_addr *addr)
 295 {
 296   struct prefix p;
 297   struct route_node *rn;
 298   struct ospf_neighbor *nbr;
 299
 300   p.family = AF_INET;
 301   p.prefixlen = IPV4_MAX_BITLEN;
 302   p.u.prefix4 = *addr;
 303
 304   rn = route_node_lookup (nbrs, &p);
 305   if (! rn)
 306     return NULL;
 307
 308   /* See comment in ospf_nbr_delete */
 309   assert (rn->info);
 310
 311   if (rn->info == NULL)
 312     {
 313       route_unlock_node (rn);
 314       return NULL;
 315     }
 316
 317   nbr = (struct ospf_neighbor *) rn->info;
 318   route_unlock_node (rn);
 319
 320   return nbr;
 321 }
 322
 323 struct ospf_neighbor *
 324 ospf_nbr_lookup_by_routerid (struct route_table *nbrs,
 325                              struct in_addr *id)
 326 {
 327   struct route_node *rn;
 328   struct ospf_neighbor *nbr;
 329
 330   for (rn = route_top (nbrs); rn; rn = route_next (rn))
 331     if ((nbr = rn->info) != NULL)
 332       if (IPV4_ADDR_SAME (&nbr->router_id, id))
 333         {
 334           route_unlock_node(rn);
 335           return nbr;
 336         }
 337
 338   return NULL;
 339 }
 340
 341 void
 342 ospf_renegotiate_optional_capabilities (struct ospf *top)
 343 {
 344   struct listnode *node;
 345   struct ospf_interface *oi;
 346   struct route_table *nbrs;
 347   struct route_node *rn;
 348   struct ospf_neighbor *nbr;
 349
 350   /* At first, flush self-originated LSAs from routing domain. */
 351   ospf_flush_self_originated_lsas_now (top);
 352
 353   /* Revert all neighbor status to ExStart. */
 354   for (ALL_LIST_ELEMENTS_RO (top->oiflist, node, oi))
 355     {
 356       if ((nbrs = oi->nbrs) == NULL)
 357         continue;
 358
 359       for (rn = route_top (nbrs); rn; rn = route_next (rn))
 360         {
 361           if ((nbr = rn->info) == NULL || nbr == oi->nbr_self)
 362             continue;
 363
 364           if (nbr->state < NSM_ExStart)
 365             continue;
 366
 367           if (IS_DEBUG_OSPF_EVENT)
 368             zlog_debug ("Renegotiate optional capabilities with neighbor(%s)", inet_ntoa (nbr->router_id));
 369
 370           OSPF_NSM_EVENT_SCHEDULE (nbr, NSM_SeqNumberMismatch);
 371         }
 372     }
 373
 374   return;
 375 }
 376
 377
 378 struct ospf_neighbor *
 379 ospf_nbr_lookup (struct ospf_interface *oi, struct ip *iph,
 380                  struct ospf_header *ospfh)
 381 {
 382   if (oi->type == OSPF_IFTYPE_VIRTUALLINK)
 383     return (ospf_nbr_lookup_by_routerid (oi->nbrs, &ospfh->router_id));
 384   else
 385     return (ospf_nbr_lookup_by_addr (oi->nbrs, &iph->ip_src));
 386 }
 387
 388 static struct ospf_neighbor *
 389 ospf_nbr_add (struct ospf_interface *oi, struct ospf_header *ospfh,
 390               struct prefix *p)
 391 {
 392   struct ospf_neighbor *nbr;
 393
 394   nbr = ospf_nbr_new (oi);
 395   nbr->state = NSM_Down;
 396   nbr->src = p->u.prefix4;
 397   memcpy (&nbr->address, p, sizeof (struct prefix));
 398
 399   nbr->nbr_nbma = NULL;
 400   if (oi->type == OSPF_IFTYPE_NBMA)
 401     {
 402       struct ospf_nbr_nbma *nbr_nbma;
 403       struct listnode *node;
 404
 405       for (ALL_LIST_ELEMENTS_RO (oi->nbr_nbma, node, nbr_nbma))
 406         {
 407           if (IPV4_ADDR_SAME(&nbr_nbma->addr, &nbr->src))
 408             {
 409               nbr_nbma->nbr = nbr;
 410               nbr->nbr_nbma = nbr_nbma;
 411
 412               if (nbr_nbma->t_poll)
 413                 OSPF_POLL_TIMER_OFF (nbr_nbma->t_poll);
 414
 415               nbr->state_change = nbr_nbma->state_change + 1;
 416             }
 417         }
 418     }
 419
 420   /* New nbr, save the crypto sequence number if necessary */
 421   if (ntohs (ospfh->auth_type) == OSPF_AUTH_CRYPTOGRAPHIC)
 422     nbr->crypt_seqnum = ospfh->u.crypt.crypt_seqnum;
 423
 424   if (IS_DEBUG_OSPF_EVENT)
 425     zlog_debug ("NSM[%s:%s]: start", IF_NAME (nbr->oi),
 426                inet_ntoa (nbr->router_id));
 427
 428   return nbr;
 429 }
 430
 431 struct ospf_neighbor *
 432 ospf_nbr_get (struct ospf_interface *oi, struct ospf_header *ospfh,
 433               struct ip *iph, struct prefix *p)
 434 {
 435   struct route_node *rn;
 436   struct prefix key;
 437   struct ospf_neighbor *nbr;
 438
 439   key.family = AF_INET;
 440   key.prefixlen = IPV4_MAX_BITLEN;
 441
 442   if (oi->type == OSPF_IFTYPE_VIRTUALLINK)
 443     key.u.prefix4 = ospfh->router_id;   /* index vlink nbrs by router-id */
 444   else
 445     key.u.prefix4 = iph->ip_src;
 446
 447   rn = route_node_get (oi->nbrs, &key);
 448   if (rn->info)
 449     {
 450       route_unlock_node (rn);
 451       nbr = rn->info;
 452
 453       if (oi->type == OSPF_IFTYPE_NBMA && nbr->state == NSM_Attempt)
 454         {
 455           nbr->src = iph->ip_src;
 456           memcpy (&nbr->address, p, sizeof (struct prefix));
 457         }
 458     }
 459   else
 460     {
 461       rn->info = nbr = ospf_nbr_add (oi, ospfh, p);
 462     }
 463
 464   nbr->router_id = ospfh->router_id;
 465
 466   return nbr;
 467 }