bgpd/bgp_nexthop.c

   1 /* BGP nexthop scan
   2  * Copyright (C) 2000 Kunihiro Ishiguro
   3  *
   4  * This file is part of GNU Zebra.
   5  *
   6  * GNU Zebra is free software; you can redistribute it and/or modify it
   7  * under the terms of the GNU General Public License as published by the
   8  * Free Software Foundation; either version 2, or (at your option) any
   9  * later version.
  10  *
  11  * GNU Zebra is distributed in the hope that it will be useful, but
  12  * WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License along
  17  * with this program; see the file COPYING; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
  19  */
  20
  21 #include <zebra.h>
  22
  23 #include "command.h"
  24 #include "thread.h"
  25 #include "prefix.h"
  26 #include "zclient.h"
  27 #include "stream.h"
  28 #include "network.h"
  29 #include "log.h"
  30 #include "memory.h"
  31 #include "hash.h"
  32 #include "jhash.h"
  33 #include "nexthop.h"
  34 #include "queue.h"
  35 #include "filter.h"
  36
  37 #include "bgpd/bgpd.h"
  38 #include "bgpd/bgp_table.h"
  39 #include "bgpd/bgp_route.h"
  40 #include "bgpd/bgp_attr.h"
  41 #include "bgpd/bgp_nexthop.h"
  42 #include "bgpd/bgp_nht.h"
  43 #include "bgpd/bgp_debug.h"
  44 #include "bgpd/bgp_damp.h"
  45 #include "bgpd/bgp_fsm.h"
  46 #include "bgpd/bgp_vty.h"
  47 #include "zebra/rib.h"
  48 #include "zebra/zserv.h"        /* For ZEBRA_SERV_PATH. */
  49
  50 char *
  51 bnc_str (struct bgp_nexthop_cache *bnc, char *buf, int size)
  52 {
  53   prefix2str(&(bnc->node->p), buf, size);
  54   return buf;
  55 }
  56
  57 void
  58 bnc_nexthop_free (struct bgp_nexthop_cache *bnc)
  59 {
  60   nexthops_free(bnc->nexthop);
  61 }
  62
  63 struct bgp_nexthop_cache *
  64 bnc_new (void)
  65 {
  66   struct bgp_nexthop_cache *bnc;
  67
  68   bnc = XCALLOC (MTYPE_BGP_NEXTHOP_CACHE, sizeof (struct bgp_nexthop_cache));
  69   LIST_INIT(&(bnc->paths));
  70   return bnc;
  71 }
  72
  73 void
  74 bnc_free (struct bgp_nexthop_cache *bnc)
  75 {
  76   bnc_nexthop_free (bnc);
  77   XFREE (MTYPE_BGP_NEXTHOP_CACHE, bnc);
  78 }
  79
  80 /* Reset and free all BGP nexthop cache. */
  81 static void
  82 bgp_nexthop_cache_reset (struct bgp_table *table)
  83 {
  84   struct bgp_node *rn;
  85   struct bgp_nexthop_cache *bnc;
  86
  87   for (rn = bgp_table_top (table); rn; rn = bgp_route_next (rn))
  88     if ((bnc = rn->info) != NULL)
  89       {
  90         bnc_free (bnc);
  91         rn->info = NULL;
  92         bgp_unlock_node (rn);
  93       }
  94 }
  95
  96 /* BGP own address structure */
  97 struct bgp_addr
  98 {
  99   struct in_addr addr;
 100   int refcnt;
 101 };
 102
 103 static void *
 104 bgp_address_hash_alloc (void *p)
 105 {
 106   const struct in_addr *val = (const struct in_addr *)p;
 107   struct bgp_addr *addr;
 108
 109   addr = XMALLOC (MTYPE_BGP_ADDR, sizeof (struct bgp_addr));
 110   addr->refcnt = 0;
 111   addr->addr.s_addr = val->s_addr;
 112
 113   return addr;
 114 }
 115
 116 static void
 117 bgp_address_hash_free (void *addr)
 118 {
 119   XFREE (MTYPE_BGP_ADDR, addr);
 120 }
 121
 122 static unsigned int
 123 bgp_address_hash_key_make (void *p)
 124 {
 125   const struct bgp_addr *addr = p;
 126
 127   return jhash_1word(addr->addr.s_addr, 0);
 128 }
 129
 130 static int
 131 bgp_address_hash_cmp (const void *p1, const void *p2)
 132 {
 133   const struct bgp_addr *addr1 = p1;
 134   const struct bgp_addr *addr2 = p2;
 135
 136   return addr1->addr.s_addr == addr2->addr.s_addr;
 137 }
 138
 139 void
 140 bgp_address_init (struct bgp *bgp)
 141 {
 142   bgp->address_hash = hash_create (bgp_address_hash_key_make,
 143                                   bgp_address_hash_cmp, NULL);
 144 }
 145
 146 void
 147 bgp_address_destroy (struct bgp *bgp)
 148 {
 149   if (bgp->address_hash == NULL)
 150     return;
 151   hash_clean(bgp->address_hash, bgp_address_hash_free);
 152   hash_free(bgp->address_hash);
 153   bgp->address_hash = NULL;
 154 }
 155
 156 static void
 157 bgp_address_add (struct bgp *bgp, struct prefix *p)
 158 {
 159   struct bgp_addr tmp;
 160   struct bgp_addr *addr;
 161
 162   tmp.addr = p->u.prefix4;
 163
 164   addr = hash_get (bgp->address_hash, &tmp, bgp_address_hash_alloc);
 165   if (!addr)
 166     return;
 167
 168   addr->refcnt++;
 169 }
 170
 171 static void
 172 bgp_address_del (struct bgp *bgp, struct prefix *p)
 173 {
 174   struct bgp_addr tmp;
 175   struct bgp_addr *addr;
 176
 177   tmp.addr = p->u.prefix4;
 178
 179   addr = hash_lookup (bgp->address_hash, &tmp);
 180   /* may have been deleted earlier by bgp_interface_down() */
 181   if (addr == NULL)
 182     return;
 183
 184   addr->refcnt--;
 185
 186   if (addr->refcnt == 0)
 187     {
 188       hash_release (bgp->address_hash, addr);
 189       XFREE (MTYPE_BGP_ADDR, addr);
 190     }
 191 }
 192
 193
 194 struct bgp_connected_ref
 195 {
 196   unsigned int refcnt;
 197 };
 198
 199 void
 200 bgp_connected_add (struct bgp *bgp, struct connected *ifc)
 201 {
 202   struct prefix p;
 203   struct prefix *addr;
 204   struct bgp_node *rn;
 205   struct bgp_connected_ref *bc;
 206   struct listnode *node, *nnode;
 207   struct peer *peer;
 208
 209   addr = ifc->address;
 210
 211   p = *(CONNECTED_PREFIX(ifc));
 212   if (addr->family == AF_INET)
 213     {
 214       apply_mask_ipv4 ((struct prefix_ipv4 *) &p);
 215
 216       if (prefix_ipv4_any ((struct prefix_ipv4 *) &p))
 217         return;
 218
 219       bgp_address_add (bgp, addr);
 220
 221       rn = bgp_node_get (bgp->connected_table[AFI_IP], (struct prefix *) &p);
 222       if (rn->info)
 223         {
 224           bc = rn->info;
 225           bc->refcnt++;
 226         }
 227       else
 228         {
 229           bc = XCALLOC (MTYPE_BGP_CONN, sizeof (struct bgp_connected_ref));
 230           bc->refcnt = 1;
 231           rn->info = bc;
 232         }
 233
 234       for (ALL_LIST_ELEMENTS (bgp->peer, node, nnode, peer))
 235         {
 236           if (peer->conf_if && (strcmp (peer->conf_if, ifc->ifp->name) == 0) &&
 237               peer->status != Established &&
 238               !CHECK_FLAG(peer->flags, PEER_FLAG_IFPEER_V6ONLY))
 239             {
 240               if (peer_active(peer))
 241                 BGP_EVENT_ADD (peer, BGP_Stop);
 242               BGP_EVENT_ADD (peer, BGP_Start);
 243             }
 244         }
 245     }
 246   else if (addr->family == AF_INET6)
 247     {
 248       apply_mask_ipv6 ((struct prefix_ipv6 *) &p);
 249
 250       if (IN6_IS_ADDR_UNSPECIFIED (&p.u.prefix6))
 251         return;
 252
 253       if (IN6_IS_ADDR_LINKLOCAL (&p.u.prefix6))
 254         return;
 255
 256       rn = bgp_node_get (bgp->connected_table[AFI_IP6], (struct prefix *) &p);
 257       if (rn->info)
 258         {
 259           bc = rn->info;
 260           bc->refcnt++;
 261         }
 262       else
 263         {
 264           bc = XCALLOC (MTYPE_BGP_CONN, sizeof (struct bgp_connected_ref));
 265           bc->refcnt = 1;
 266           rn->info = bc;
 267         }
 268     }
 269 }
 270
 271 void
 272 bgp_connected_delete (struct bgp *bgp, struct connected *ifc)
 273 {
 274   struct prefix p;
 275   struct prefix *addr;
 276   struct bgp_node *rn;
 277   struct bgp_connected_ref *bc;
 278
 279   addr = ifc->address;
 280
 281   p = *(CONNECTED_PREFIX(ifc));
 282   if (addr->family == AF_INET)
 283     {
 284       apply_mask_ipv4 ((struct prefix_ipv4 *) &p);
 285
 286       if (prefix_ipv4_any ((struct prefix_ipv4 *) &p))
 287         return;
 288
 289       bgp_address_del (bgp, addr);
 290
 291       rn = bgp_node_lookup (bgp->connected_table[AFI_IP], &p);
 292       if (! rn)
 293         return;
 294
 295       bc = rn->info;
 296       bc->refcnt--;
 297       if (bc->refcnt == 0)
 298         {
 299           XFREE (MTYPE_BGP_CONN, bc);
 300           rn->info = NULL;
 301         }
 302       bgp_unlock_node (rn);
 303       bgp_unlock_node (rn);
 304     }
 305   else if (addr->family == AF_INET6)
 306     {
 307       apply_mask_ipv6 ((struct prefix_ipv6 *) &p);
 308
 309       if (IN6_IS_ADDR_UNSPECIFIED (&p.u.prefix6))
 310         return;
 311
 312       if (IN6_IS_ADDR_LINKLOCAL (&p.u.prefix6))
 313         return;
 314
 315       rn = bgp_node_lookup (bgp->connected_table[AFI_IP6], (struct prefix *) &p);
 316       if (! rn)
 317         return;
 318
 319       bc = rn->info;
 320       bc->refcnt--;
 321       if (bc->refcnt == 0)
 322         {
 323           XFREE (MTYPE_BGP_CONN, bc);
 324           rn->info = NULL;
 325         }
 326       bgp_unlock_node (rn);
 327       bgp_unlock_node (rn);
 328     }
 329 }
 330
 331 int
 332 bgp_nexthop_self (struct bgp *bgp, struct in_addr nh_addr)
 333 {
 334   struct bgp_addr tmp, *addr;
 335
 336   tmp.addr = nh_addr;
 337
 338   addr = hash_lookup (bgp->address_hash, &tmp);
 339   if (addr)
 340     return 1;
 341
 342   return 0;
 343 }
 344
 345 int
 346 bgp_multiaccess_check_v4 (struct in_addr nexthop, struct peer *peer)
 347 {
 348   struct bgp_node *rn1;
 349   struct bgp_node *rn2;
 350   struct prefix p;
 351   int ret;
 352
 353   p.family = AF_INET;
 354   p.prefixlen = IPV4_MAX_BITLEN;
 355   p.u.prefix4 = nexthop;
 356
 357   rn1 = bgp_node_match (peer->bgp->connected_table[AFI_IP], &p);
 358   if (!rn1)
 359     return 0;
 360
 361   p.family = AF_INET;
 362   p.prefixlen = IPV4_MAX_BITLEN;
 363   p.u.prefix4 = peer->su.sin.sin_addr;
 364
 365   rn2 = bgp_node_match (peer->bgp->connected_table[AFI_IP], &p);
 366   if (!rn2)
 367     {
 368       bgp_unlock_node(rn1);
 369       return 0;
 370     }
 371
 372   ret = (rn1 == rn2) ? 1 : 0;
 373
 374   bgp_unlock_node(rn1);
 375   bgp_unlock_node(rn2);
 376
 377   return (ret);
 378 }
 379
 380 static void
 381 bgp_show_nexthops (struct vty *vty, struct bgp *bgp, int detail)
 382 {
 383   struct bgp_node *rn;
 384   struct bgp_nexthop_cache *bnc;
 385   char buf[PREFIX2STR_BUFFER];
 386   struct nexthop *nexthop;
 387   time_t tbuf;
 388   afi_t afi;
 389
 390   vty_out (vty, "Current BGP nexthop cache:\n");
 391   for (afi = AFI_IP ; afi < AFI_MAX ; afi++)
 392     {
 393       if (!bgp->nexthop_cache_table[afi])
 394         continue;
 395
 396       for (rn = bgp_table_top (bgp->nexthop_cache_table[afi]); rn; rn = bgp_route_next (rn))
 397         {
 398           if ((bnc = rn->info) != NULL)
 399             {
 400               if (CHECK_FLAG(bnc->flags, BGP_NEXTHOP_VALID))
 401                 {
 402                   vty_out (vty, " %s valid [IGP metric %d], #paths %d\n",
 403                            inet_ntop (rn->p.family, &rn->p.u.prefix, buf, sizeof (buf)),
 404                            bnc->metric, bnc->path_count);
 405                   if (detail)
 406                     for (nexthop = bnc->nexthop; nexthop; nexthop = nexthop->next)
 407                       switch (nexthop->type)
 408                         {
 409                         case NEXTHOP_TYPE_IPV6:
 410                           vty_out (vty, "  gate %s\n",
 411                                    inet_ntop(AF_INET6, &nexthop->gate.ipv6, buf, sizeof(buf)));
 412                           break;
 413                         case NEXTHOP_TYPE_IPV6_IFINDEX:
 414                           vty_out (vty, "  gate %s, if %s\n",
 415                                   inet_ntop(AF_INET6, &nexthop->gate.ipv6, buf,
 416                                             sizeof (buf)),
 417                                   ifindex2ifname(nexthop->ifindex, bgp->vrf_id));
 418                           break;
 419                         case NEXTHOP_TYPE_IPV4:
 420                           vty_out (vty, "  gate %s\n",
 421                                    inet_ntop(AF_INET, &nexthop->gate.ipv4, buf, sizeof(buf)));
 422                           break;
 423                         case NEXTHOP_TYPE_IFINDEX:
 424                           vty_out (vty, "  if %s\n",
 425                                    ifindex2ifname(nexthop->ifindex, bgp->vrf_id));
 426                           break;
 427                         case NEXTHOP_TYPE_IPV4_IFINDEX:
 428                           vty_out (vty, "  gate %s, if %s\n",
 429                                    inet_ntop(AF_INET, &nexthop->gate.ipv4, buf,
 430                                              sizeof (buf)),
 431                                    ifindex2ifname(nexthop->ifindex, bgp->vrf_id));
 432                           break;
 433                         default:
 434                           vty_out (vty, "  invalid nexthop type %u\n",
 435                                    nexthop->type);
 436                         }
 437                 }
 438               else
 439                 {
 440                   vty_out (vty, " %s invalid\n",
 441                            inet_ntop(rn->p.family, &rn->p.u.prefix, buf, sizeof(buf)));
 442                   if (CHECK_FLAG(bnc->flags, BGP_NEXTHOP_CONNECTED))
 443                     vty_out (vty, "  Must be Connected\n");
 444                 }
 445               tbuf = time(NULL) - (bgp_clock() - bnc->last_update);
 446               vty_out (vty, "  Last update: %s", ctime(&tbuf));
 447               vty_out (vty, "\n");
 448             }
 449         }
 450     }
 451 }
 452
 453 static int
 454 show_ip_bgp_nexthop_table (struct vty *vty, const char *name, int detail)
 455 {
 456   struct bgp *bgp;
 457
 458   if (name)
 459     bgp = bgp_lookup_by_name (name);
 460   else
 461     bgp = bgp_get_default ();
 462   if (!bgp)
 463     {
 464       vty_out (vty, "%% No such BGP instance exist\n");
 465       return CMD_WARNING;
 466     }
 467
 468   bgp_show_nexthops (vty, bgp, detail);
 469
 470   return CMD_SUCCESS;
 471 }
 472
 473 static void
 474 bgp_show_all_instances_nexthops_vty (struct vty *vty)
 475 {
 476   struct listnode *node, *nnode;
 477   struct bgp *bgp;
 478
 479   for (ALL_LIST_ELEMENTS (bm->bgp, node, nnode, bgp))
 480     {
 481       vty_out (vty, "\nInstance %s:\n",
 482                (bgp->inst_type == BGP_INSTANCE_TYPE_DEFAULT) ? "Default" : bgp->name);
 483       bgp_show_nexthops (vty, bgp, 0);
 484     }
 485 }
 486
 487 DEFUN (show_ip_bgp_nexthop,
 488        show_ip_bgp_nexthop_cmd,
 489        "show [ip] bgp [<view|vrf> VIEWVRFNAME] nexthop [detail]",
 490        SHOW_STR
 491        IP_STR
 492        BGP_STR
 493        BGP_INSTANCE_HELP_STR
 494        "BGP nexthop table\n"
 495        "Show detailed information\n")
 496 {
 497   int idx = 0;
 498   char *vrf = argv_find (argv, argc, "WORD", &idx) ? argv[idx]->arg : NULL;
 499   int detail = argv_find (argv, argc, "detail", &idx) ? 1 : 0;
 500   return show_ip_bgp_nexthop_table (vty, vrf, detail);
 501 }
 502
 503 DEFUN (show_ip_bgp_instance_all_nexthop,
 504        show_ip_bgp_instance_all_nexthop_cmd,
 505        "show [ip] bgp <view|vrf> all nexthop",
 506        SHOW_STR
 507        IP_STR
 508        BGP_STR
 509        BGP_INSTANCE_ALL_HELP_STR
 510        "BGP nexthop table\n")
 511 {
 512   bgp_show_all_instances_nexthops_vty (vty);
 513   return CMD_SUCCESS;
 514 }
 515
 516 void
 517 bgp_scan_init (struct bgp *bgp)
 518 {
 519   afi_t afi;
 520
 521   for (afi = AFI_IP; afi < AFI_MAX; afi++)
 522     {
 523       bgp->nexthop_cache_table[afi] = bgp_table_init (afi, SAFI_UNICAST);
 524       bgp->connected_table[afi] = bgp_table_init (afi, SAFI_UNICAST);
 525       bgp->import_check_table[afi] = bgp_table_init (afi, SAFI_UNICAST);
 526     }
 527 }
 528
 529 void
 530 bgp_scan_vty_init (void)
 531 {
 532   install_element (VIEW_NODE, &show_ip_bgp_nexthop_cmd);
 533   install_element (VIEW_NODE, &show_ip_bgp_instance_all_nexthop_cmd);
 534 }
 535
 536 void
 537 bgp_scan_finish (struct bgp *bgp)
 538 {
 539   afi_t afi;
 540
 541   for (afi = AFI_IP; afi < AFI_MAX; afi++)
 542     {
 543       /* Only the current one needs to be reset. */
 544       bgp_nexthop_cache_reset (bgp->nexthop_cache_table[afi]);
 545       bgp_table_unlock (bgp->nexthop_cache_table[afi]);
 546       bgp->nexthop_cache_table[afi] = NULL;
 547
 548       bgp_table_unlock (bgp->connected_table[afi]);
 549       bgp->connected_table[afi] = NULL;
 550
 551       bgp_table_unlock (bgp->import_check_table[afi]);
 552       bgp->import_check_table[afi] = NULL;
 553     }
 554 }