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
  17 along with GNU Zebra; see the file COPYING.  If not, write to the Free
  18 Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
  19 02111-1307, USA.  */
  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);
 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 #ifdef HAVE_IPV6
 247   else if (addr->family == AF_INET6)
 248     {
 249       apply_mask_ipv6 ((struct prefix_ipv6 *) &p);
 250
 251       if (IN6_IS_ADDR_UNSPECIFIED (&p.u.prefix6))
 252         return;
 253
 254       if (IN6_IS_ADDR_LINKLOCAL (&p.u.prefix6))
 255         return;
 256
 257       rn = bgp_node_get (bgp->connected_table[AFI_IP6], (struct prefix *) &p);
 258       if (rn->info)
 259         {
 260           bc = rn->info;
 261           bc->refcnt++;
 262         }
 263       else
 264         {
 265           bc = XCALLOC (MTYPE_BGP_CONN, sizeof (struct bgp_connected_ref));
 266           bc->refcnt = 1;
 267           rn->info = bc;
 268         }
 269     }
 270 #endif /* HAVE_IPV6 */
 271 }
 272
 273 void
 274 bgp_connected_delete (struct bgp *bgp, struct connected *ifc)
 275 {
 276   struct prefix p;
 277   struct prefix *addr;
 278   struct bgp_node *rn;
 279   struct bgp_connected_ref *bc;
 280
 281   addr = ifc->address;
 282
 283   p = *(CONNECTED_PREFIX(ifc));
 284   if (addr->family == AF_INET)
 285     {
 286       apply_mask_ipv4 ((struct prefix_ipv4 *) &p);
 287
 288       if (prefix_ipv4_any ((struct prefix_ipv4 *) &p))
 289         return;
 290
 291       bgp_address_del (bgp, addr);
 292
 293       rn = bgp_node_lookup (bgp->connected_table[AFI_IP], &p);
 294       if (! rn)
 295         return;
 296
 297       bc = rn->info;
 298       bc->refcnt--;
 299       if (bc->refcnt == 0)
 300         {
 301           XFREE (MTYPE_BGP_CONN, bc);
 302           rn->info = NULL;
 303         }
 304       bgp_unlock_node (rn);
 305       bgp_unlock_node (rn);
 306     }
 307 #ifdef HAVE_IPV6
 308   else if (addr->family == AF_INET6)
 309     {
 310       apply_mask_ipv6 ((struct prefix_ipv6 *) &p);
 311
 312       if (IN6_IS_ADDR_UNSPECIFIED (&p.u.prefix6))
 313         return;
 314
 315       if (IN6_IS_ADDR_LINKLOCAL (&p.u.prefix6))
 316         return;
 317
 318       rn = bgp_node_lookup (bgp->connected_table[AFI_IP6], (struct prefix *) &p);
 319       if (! rn)
 320         return;
 321
 322       bc = rn->info;
 323       bc->refcnt--;
 324       if (bc->refcnt == 0)
 325         {
 326           XFREE (MTYPE_BGP_CONN, bc);
 327           rn->info = NULL;
 328         }
 329       bgp_unlock_node (rn);
 330       bgp_unlock_node (rn);
 331     }
 332 #endif /* HAVE_IPV6 */
 333 }
 334
 335 int
 336 bgp_nexthop_self (struct bgp *bgp, struct attr *attr)
 337 {
 338   struct bgp_addr tmp, *addr;
 339
 340   tmp.addr = attr->nexthop;
 341
 342   addr = hash_lookup (bgp->address_hash, &tmp);
 343   if (addr)
 344     return 1;
 345
 346   return 0;
 347 }
 348
 349 int
 350 bgp_multiaccess_check_v4 (struct in_addr nexthop, struct peer *peer)
 351 {
 352   struct bgp_node *rn1;
 353   struct bgp_node *rn2;
 354   struct prefix p;
 355   int ret;
 356
 357   p.family = AF_INET;
 358   p.prefixlen = IPV4_MAX_BITLEN;
 359   p.u.prefix4 = nexthop;
 360
 361   rn1 = bgp_node_match (peer->bgp->connected_table[AFI_IP], &p);
 362   if (!rn1)
 363     return 0;
 364
 365   p.family = AF_INET;
 366   p.prefixlen = IPV4_MAX_BITLEN;
 367   p.u.prefix4 = peer->su.sin.sin_addr;
 368
 369   rn2 = bgp_node_match (peer->bgp->connected_table[AFI_IP], &p);
 370   if (!rn2)
 371     {
 372       bgp_unlock_node(rn1);
 373       return 0;
 374     }
 375
 376   ret = (rn1 == rn2) ? 1 : 0;
 377
 378   bgp_unlock_node(rn1);
 379   bgp_unlock_node(rn2);
 380
 381   return (ret);
 382 }
 383
 384 static void
 385 bgp_show_nexthops (struct vty *vty, struct bgp *bgp, int detail)
 386 {
 387   struct bgp_node *rn;
 388   struct bgp_nexthop_cache *bnc;
 389   char buf[PREFIX2STR_BUFFER];
 390   struct nexthop *nexthop;
 391   time_t tbuf;
 392   afi_t afi;
 393
 394   vty_out (vty, "Current BGP nexthop cache:%s", VTY_NEWLINE);
 395   for (afi = AFI_IP ; afi < AFI_MAX ; afi++)
 396     {
 397       if (!bgp->nexthop_cache_table[afi])
 398         continue;
 399
 400       for (rn = bgp_table_top (bgp->nexthop_cache_table[afi]); rn; rn = bgp_route_next (rn))
 401         {
 402           if ((bnc = rn->info) != NULL)
 403             {
 404               if (CHECK_FLAG(bnc->flags, BGP_NEXTHOP_VALID))
 405                 {
 406                   vty_out (vty, " %s valid [IGP metric %d], #paths %d%s",
 407                            inet_ntop (rn->p.family, &rn->p.u.prefix, buf, sizeof (buf)),
 408                            bnc->metric, bnc->path_count, VTY_NEWLINE);
 409                   if (detail)
 410                     for (nexthop = bnc->nexthop; nexthop; nexthop = nexthop->next)
 411                       switch (nexthop->type)
 412                         {
 413                         case NEXTHOP_TYPE_IPV6:
 414                           vty_out (vty, "  gate %s%s",
 415                                    inet_ntop (AF_INET6, &nexthop->gate.ipv6,
 416                                               buf, sizeof (buf)), VTY_NEWLINE);
 417                           break;
 418                         case NEXTHOP_TYPE_IPV6_IFINDEX:
 419                           vty_out(vty, "  gate %s, if %s%s",
 420                                   inet_ntop(AF_INET6, &nexthop->gate.ipv6, buf,
 421                                             sizeof (buf)),
 422                                   ifindex2ifname(nexthop->ifindex),
 423                                   VTY_NEWLINE);
 424                           break;
 425                         case NEXTHOP_TYPE_IPV4:
 426                           vty_out (vty, "  gate %s%s",
 427                                    inet_ntop (AF_INET, &nexthop->gate.ipv4, buf,
 428                                               sizeof (buf)), VTY_NEWLINE);
 429                           break;
 430                         case NEXTHOP_TYPE_IFINDEX:
 431                           vty_out (vty, "  if %s%s",
 432                                    ifindex2ifname(nexthop->ifindex), VTY_NEWLINE);
 433                           break;
 434                         case NEXTHOP_TYPE_IPV4_IFINDEX:
 435                           vty_out (vty, "  gate %s, if %s%s",
 436                                    inet_ntop(AF_INET, &nexthop->gate.ipv4, buf,
 437                                              sizeof (buf)),
 438                                    ifindex2ifname(nexthop->ifindex), VTY_NEWLINE);
 439                           break;
 440                         default:
 441                           vty_out (vty, "  invalid nexthop type %u%s",
 442                                    nexthop->type, VTY_NEWLINE);
 443                         }
 444                 }
 445               else
 446                 {
 447                   vty_out (vty, " %s invalid%s",
 448                            inet_ntop (rn->p.family, &rn->p.u.prefix,
 449                                       buf, sizeof (buf)), VTY_NEWLINE);
 450                   if (CHECK_FLAG(bnc->flags, BGP_NEXTHOP_CONNECTED))
 451                     vty_out (vty, "  Must be Connected%s", VTY_NEWLINE);
 452                 }
 453               tbuf = time(NULL) - (bgp_clock() - bnc->last_update);
 454               vty_out (vty, "  Last update: %s", ctime(&tbuf));
 455               vty_out(vty, "%s", VTY_NEWLINE);
 456             }
 457         }
 458     }
 459 }
 460
 461 static int
 462 show_ip_bgp_nexthop_table (struct vty *vty, const char *name, int detail)
 463 {
 464   struct bgp *bgp;
 465
 466   if (name)
 467     bgp = bgp_lookup_by_name (name);
 468   else
 469     bgp = bgp_get_default ();
 470   if (!bgp)
 471     {
 472       vty_out (vty, "%% No such BGP instance exist%s", VTY_NEWLINE);
 473       return CMD_WARNING;
 474     }
 475
 476   bgp_show_nexthops (vty, bgp, detail);
 477
 478   return CMD_SUCCESS;
 479 }
 480
 481 static void
 482 bgp_show_all_instances_nexthops_vty (struct vty *vty)
 483 {
 484   struct listnode *node, *nnode;
 485   struct bgp *bgp;
 486
 487   for (ALL_LIST_ELEMENTS (bm->bgp, node, nnode, bgp))
 488     {
 489       vty_out (vty, "%sInstance %s:%s",
 490                VTY_NEWLINE,
 491                (bgp->inst_type == BGP_INSTANCE_TYPE_DEFAULT) ? "Default" : bgp->name,
 492                VTY_NEWLINE);
 493       bgp_show_nexthops (vty, bgp, 0);
 494     }
 495 }
 496
 497 DEFUN (show_ip_bgp_nexthop,
 498        show_ip_bgp_nexthop_cmd,
 499        "show [ip] bgp [<view|vrf> VRFNAME] nexthop [detail]",
 500        SHOW_STR
 501        IP_STR
 502        BGP_STR
 503        BGP_INSTANCE_HELP_STR
 504        "BGP nexthop table\n"
 505        "Show detailed information\n")
 506 {
 507   int idx = 0;
 508   char *vrf = argv_find (argv, argc, "VRFNAME", &idx) ? argv[idx]->arg : NULL;
 509   int detail = argv_find (argv, argc, "detail", &idx) ? 1 : 0;
 510   return show_ip_bgp_nexthop_table (vty, vrf, detail);
 511 }
 512
 513 DEFUN (show_ip_bgp_instance_all_nexthop,
 514        show_ip_bgp_instance_all_nexthop_cmd,
 515        "show [ip] bgp <view|vrf> all nexthop",
 516        SHOW_STR
 517        IP_STR
 518        BGP_STR
 519        BGP_INSTANCE_ALL_HELP_STR
 520        "BGP nexthop table\n")
 521 {
 522   bgp_show_all_instances_nexthops_vty (vty);
 523   return CMD_SUCCESS;
 524 }
 525
 526 void
 527 bgp_scan_init (struct bgp *bgp)
 528 {
 529   afi_t afi;
 530
 531   for (afi = AFI_IP; afi < AFI_MAX; afi++)
 532     {
 533       bgp->nexthop_cache_table[afi] = bgp_table_init (afi, SAFI_UNICAST);
 534       bgp->connected_table[afi] = bgp_table_init (afi, SAFI_UNICAST);
 535       bgp->import_check_table[afi] = bgp_table_init (afi, SAFI_UNICAST);
 536     }
 537 }
 538
 539 void
 540 bgp_scan_vty_init (void)
 541 {
 542   install_element (VIEW_NODE, &show_ip_bgp_nexthop_cmd);
 543   install_element (VIEW_NODE, &show_ip_bgp_instance_all_nexthop_cmd);
 544 }
 545
 546 void
 547 bgp_scan_finish (struct bgp *bgp)
 548 {
 549   afi_t afi;
 550
 551   for (afi = AFI_IP; afi < AFI_MAX; afi++)
 552     {
 553       /* Only the current one needs to be reset. */
 554       bgp_nexthop_cache_reset (bgp->nexthop_cache_table[afi]);
 555       bgp_table_unlock (bgp->nexthop_cache_table[afi]);
 556       bgp->nexthop_cache_table[afi] = NULL;
 557
 558       bgp_table_unlock (bgp->connected_table[afi]);
 559       bgp->connected_table[afi] = NULL;
 560
 561       bgp_table_unlock (bgp->import_check_table[afi]);
 562       bgp->import_check_table[afi] = NULL;
 563     }
 564 }