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 *bnc_str(struct bgp_nexthop_cache *bnc, char *buf, int size)
  51 {
  52         prefix2str(&(bnc->node->p), buf, size);
  53         return buf;
  54 }
  55
  56 void bnc_nexthop_free(struct bgp_nexthop_cache *bnc)
  57 {
  58         nexthops_free(bnc->nexthop);
  59 }
  60
  61 struct bgp_nexthop_cache *bnc_new(void)
  62 {
  63         struct bgp_nexthop_cache *bnc;
  64
  65         bnc = XCALLOC(MTYPE_BGP_NEXTHOP_CACHE,
  66                       sizeof(struct bgp_nexthop_cache));
  67         LIST_INIT(&(bnc->paths));
  68         return bnc;
  69 }
  70
  71 void bnc_free(struct bgp_nexthop_cache *bnc)
  72 {
  73         bnc_nexthop_free(bnc);
  74         XFREE(MTYPE_BGP_NEXTHOP_CACHE, bnc);
  75 }
  76
  77 /* Reset and free all BGP nexthop cache. */
  78 static void bgp_nexthop_cache_reset(struct bgp_table *table)
  79 {
  80         struct bgp_node *rn;
  81         struct bgp_nexthop_cache *bnc;
  82
  83         for (rn = bgp_table_top(table); rn; rn = bgp_route_next(rn))
  84                 if ((bnc = rn->info) != NULL) {
  85                         bnc_free(bnc);
  86                         rn->info = NULL;
  87                         bgp_unlock_node(rn);
  88                 }
  89 }
  90
  91 static void *bgp_tip_hash_alloc(void *p)
  92 {
  93         const struct in_addr *val = (const struct in_addr *)p;
  94         struct tip_addr *addr;
  95
  96         addr = XMALLOC(MTYPE_TIP_ADDR, sizeof(struct tip_addr));
  97         addr->refcnt = 0;
  98         addr->addr.s_addr = val->s_addr;
  99
 100         return addr;
 101 }
 102
 103 static void bgp_tip_hash_free(void *addr)
 104 {
 105         XFREE(MTYPE_TIP_ADDR, addr);
 106 }
 107
 108 static unsigned int bgp_tip_hash_key_make(void *p)
 109 {
 110         const struct tip_addr *addr = p;
 111
 112         return jhash_1word(addr->addr.s_addr, 0);
 113 }
 114
 115 static int bgp_tip_hash_cmp(const void *p1, const void *p2)
 116 {
 117         const struct tip_addr *addr1 = p1;
 118         const struct tip_addr *addr2 = p2;
 119
 120         return addr1->addr.s_addr == addr2->addr.s_addr;
 121 }
 122
 123 void bgp_tip_hash_init(struct bgp *bgp)
 124 {
 125         bgp->tip_hash = hash_create(bgp_tip_hash_key_make,
 126                                         bgp_tip_hash_cmp, NULL);
 127 }
 128
 129 void bgp_tip_hash_destroy(struct bgp *bgp)
 130 {
 131         if (bgp->tip_hash == NULL)
 132                 return;
 133         hash_clean(bgp->tip_hash, bgp_tip_hash_free);
 134         hash_free(bgp->tip_hash);
 135         bgp->tip_hash = NULL;
 136 }
 137
 138 void bgp_tip_add(struct bgp *bgp, struct in_addr *tip)
 139 {
 140         struct tip_addr tmp;
 141         struct tip_addr *addr;
 142
 143         tmp.addr = *tip;
 144
 145         addr = hash_get(bgp->tip_hash, &tmp, bgp_tip_hash_alloc);
 146         if (!addr)
 147                 return;
 148
 149         addr->refcnt++;
 150 }
 151
 152 void bgp_tip_del(struct bgp *bgp, struct in_addr *tip)
 153 {
 154         struct tip_addr tmp;
 155         struct tip_addr *addr;
 156
 157         tmp.addr = *tip;
 158
 159         addr = hash_lookup(bgp->tip_hash, &tmp);
 160         /* may have been deleted earlier by bgp_interface_down() */
 161         if (addr == NULL)
 162                 return;
 163
 164         addr->refcnt--;
 165
 166         if (addr->refcnt == 0) {
 167                 hash_release(bgp->tip_hash, addr);
 168                 XFREE(MTYPE_TIP_ADDR, addr);
 169         }
 170 }
 171
 172 static void *bgp_address_hash_alloc(void *p)
 173 {
 174         const struct in_addr *val = (const struct in_addr *)p;
 175         struct bgp_addr *addr;
 176
 177         addr = XMALLOC(MTYPE_BGP_ADDR, sizeof(struct bgp_addr));
 178         addr->refcnt = 0;
 179         addr->addr.s_addr = val->s_addr;
 180
 181         return addr;
 182 }
 183
 184 static void bgp_address_hash_free(void *addr)
 185 {
 186         XFREE(MTYPE_BGP_ADDR, addr);
 187 }
 188
 189 static unsigned int bgp_address_hash_key_make(void *p)
 190 {
 191         const struct bgp_addr *addr = p;
 192
 193         return jhash_1word(addr->addr.s_addr, 0);
 194 }
 195
 196 static int bgp_address_hash_cmp(const void *p1, const void *p2)
 197 {
 198         const struct bgp_addr *addr1 = p1;
 199         const struct bgp_addr *addr2 = p2;
 200
 201         return addr1->addr.s_addr == addr2->addr.s_addr;
 202 }
 203
 204 void bgp_address_init(struct bgp *bgp)
 205 {
 206         bgp->address_hash = hash_create(bgp_address_hash_key_make,
 207                                         bgp_address_hash_cmp, NULL);
 208 }
 209
 210 void bgp_address_destroy(struct bgp *bgp)
 211 {
 212         if (bgp->address_hash == NULL)
 213                 return;
 214         hash_clean(bgp->address_hash, bgp_address_hash_free);
 215         hash_free(bgp->address_hash);
 216         bgp->address_hash = NULL;
 217 }
 218
 219 static void bgp_address_add(struct bgp *bgp, struct prefix *p)
 220 {
 221         struct bgp_addr tmp;
 222         struct bgp_addr *addr;
 223
 224         tmp.addr = p->u.prefix4;
 225
 226         addr = hash_get(bgp->address_hash, &tmp, bgp_address_hash_alloc);
 227         if (!addr)
 228                 return;
 229
 230         addr->refcnt++;
 231 }
 232
 233 static void bgp_address_del(struct bgp *bgp, struct prefix *p)
 234 {
 235         struct bgp_addr tmp;
 236         struct bgp_addr *addr;
 237
 238         tmp.addr = p->u.prefix4;
 239
 240         addr = hash_lookup(bgp->address_hash, &tmp);
 241         /* may have been deleted earlier by bgp_interface_down() */
 242         if (addr == NULL)
 243                 return;
 244
 245         addr->refcnt--;
 246
 247         if (addr->refcnt == 0) {
 248                 hash_release(bgp->address_hash, addr);
 249                 XFREE(MTYPE_BGP_ADDR, addr);
 250         }
 251 }
 252
 253
 254 struct bgp_connected_ref {
 255         unsigned int refcnt;
 256 };
 257
 258 void bgp_connected_add(struct bgp *bgp, struct connected *ifc)
 259 {
 260         struct prefix p;
 261         struct prefix *addr;
 262         struct bgp_node *rn;
 263         struct bgp_connected_ref *bc;
 264         struct listnode *node, *nnode;
 265         struct peer *peer;
 266
 267         addr = ifc->address;
 268
 269         p = *(CONNECTED_PREFIX(ifc));
 270         if (addr->family == AF_INET) {
 271                 apply_mask_ipv4((struct prefix_ipv4 *)&p);
 272
 273                 if (prefix_ipv4_any((struct prefix_ipv4 *)&p))
 274                         return;
 275
 276                 bgp_address_add(bgp, addr);
 277
 278                 rn = bgp_node_get(bgp->connected_table[AFI_IP],
 279                                   (struct prefix *)&p);
 280                 if (rn->info) {
 281                         bc = rn->info;
 282                         bc->refcnt++;
 283                 } else {
 284                         bc = XCALLOC(MTYPE_BGP_CONN,
 285                                      sizeof(struct bgp_connected_ref));
 286                         bc->refcnt = 1;
 287                         rn->info = bc;
 288                 }
 289
 290                 for (ALL_LIST_ELEMENTS(bgp->peer, node, nnode, peer)) {
 291                         if (peer->conf_if
 292                             && (strcmp(peer->conf_if, ifc->ifp->name) == 0)
 293                             && peer->status != Established
 294                             && !CHECK_FLAG(peer->flags,
 295                                            PEER_FLAG_IFPEER_V6ONLY)) {
 296                                 if (peer_active(peer))
 297                                         BGP_EVENT_ADD(peer, BGP_Stop);
 298                                 BGP_EVENT_ADD(peer, BGP_Start);
 299                         }
 300                 }
 301         } else if (addr->family == AF_INET6) {
 302                 apply_mask_ipv6((struct prefix_ipv6 *)&p);
 303
 304                 if (IN6_IS_ADDR_UNSPECIFIED(&p.u.prefix6))
 305                         return;
 306
 307                 if (IN6_IS_ADDR_LINKLOCAL(&p.u.prefix6))
 308                         return;
 309
 310                 rn = bgp_node_get(bgp->connected_table[AFI_IP6],
 311                                   (struct prefix *)&p);
 312                 if (rn->info) {
 313                         bc = rn->info;
 314                         bc->refcnt++;
 315                 } else {
 316                         bc = XCALLOC(MTYPE_BGP_CONN,
 317                                      sizeof(struct bgp_connected_ref));
 318                         bc->refcnt = 1;
 319                         rn->info = bc;
 320                 }
 321         }
 322 }
 323
 324 void bgp_connected_delete(struct bgp *bgp, struct connected *ifc)
 325 {
 326         struct prefix p;
 327         struct prefix *addr;
 328         struct bgp_node *rn;
 329         struct bgp_connected_ref *bc;
 330
 331         addr = ifc->address;
 332
 333         p = *(CONNECTED_PREFIX(ifc));
 334         if (addr->family == AF_INET) {
 335                 apply_mask_ipv4((struct prefix_ipv4 *)&p);
 336
 337                 if (prefix_ipv4_any((struct prefix_ipv4 *)&p))
 338                         return;
 339
 340                 bgp_address_del(bgp, addr);
 341
 342                 rn = bgp_node_lookup(bgp->connected_table[AFI_IP], &p);
 343                 if (!rn)
 344                         return;
 345
 346                 bc = rn->info;
 347                 bc->refcnt--;
 348                 if (bc->refcnt == 0) {
 349                         XFREE(MTYPE_BGP_CONN, bc);
 350                         rn->info = NULL;
 351                 }
 352                 bgp_unlock_node(rn);
 353                 bgp_unlock_node(rn);
 354         } else if (addr->family == AF_INET6) {
 355                 apply_mask_ipv6((struct prefix_ipv6 *)&p);
 356
 357                 if (IN6_IS_ADDR_UNSPECIFIED(&p.u.prefix6))
 358                         return;
 359
 360                 if (IN6_IS_ADDR_LINKLOCAL(&p.u.prefix6))
 361                         return;
 362
 363                 rn = bgp_node_lookup(bgp->connected_table[AFI_IP6],
 364                                      (struct prefix *)&p);
 365                 if (!rn)
 366                         return;
 367
 368                 bc = rn->info;
 369                 bc->refcnt--;
 370                 if (bc->refcnt == 0) {
 371                         XFREE(MTYPE_BGP_CONN, bc);
 372                         rn->info = NULL;
 373                 }
 374                 bgp_unlock_node(rn);
 375                 bgp_unlock_node(rn);
 376         }
 377 }
 378
 379 int bgp_nexthop_self(struct bgp *bgp, struct in_addr nh_addr)
 380 {
 381         struct bgp_addr tmp, *addr;
 382         struct tip_addr tmp_tip, *tip;
 383
 384         tmp.addr = nh_addr;
 385
 386         addr = hash_lookup(bgp->address_hash, &tmp);
 387         if (addr)
 388                 return 1;
 389
 390         tmp_tip.addr = nh_addr;
 391         tip = hash_lookup(bgp->tip_hash, &tmp_tip);
 392         if (tip)
 393                 return 1;
 394
 395         return 0;
 396 }
 397
 398 int bgp_multiaccess_check_v4(struct in_addr nexthop, struct peer *peer)
 399 {
 400         struct bgp_node *rn1;
 401         struct bgp_node *rn2;
 402         struct prefix p;
 403         int ret;
 404
 405         p.family = AF_INET;
 406         p.prefixlen = IPV4_MAX_BITLEN;
 407         p.u.prefix4 = nexthop;
 408
 409         rn1 = bgp_node_match(peer->bgp->connected_table[AFI_IP], &p);
 410         if (!rn1)
 411                 return 0;
 412
 413         p.family = AF_INET;
 414         p.prefixlen = IPV4_MAX_BITLEN;
 415         p.u.prefix4 = peer->su.sin.sin_addr;
 416
 417         rn2 = bgp_node_match(peer->bgp->connected_table[AFI_IP], &p);
 418         if (!rn2) {
 419                 bgp_unlock_node(rn1);
 420                 return 0;
 421         }
 422
 423         ret = (rn1 == rn2) ? 1 : 0;
 424
 425         bgp_unlock_node(rn1);
 426         bgp_unlock_node(rn2);
 427
 428         return (ret);
 429 }
 430
 431 static void bgp_show_nexthops(struct vty *vty, struct bgp *bgp, int detail)
 432 {
 433         struct bgp_node *rn;
 434         struct bgp_nexthop_cache *bnc;
 435         char buf[PREFIX2STR_BUFFER];
 436         struct nexthop *nexthop;
 437         time_t tbuf;
 438         afi_t afi;
 439
 440         vty_out(vty, "Current BGP nexthop cache:\n");
 441         for (afi = AFI_IP; afi < AFI_MAX; afi++) {
 442                 if (!bgp->nexthop_cache_table[afi])
 443                         continue;
 444
 445                 for (rn = bgp_table_top(bgp->nexthop_cache_table[afi]); rn;
 446                      rn = bgp_route_next(rn)) {
 447                         if ((bnc = rn->info) != NULL) {
 448                                 if (CHECK_FLAG(bnc->flags, BGP_NEXTHOP_VALID)) {
 449                                         vty_out(vty,
 450                                                 " %s valid [IGP metric %d], #paths %d\n",
 451                                                 inet_ntop(rn->p.family,
 452                                                           &rn->p.u.prefix, buf,
 453                                                           sizeof(buf)),
 454                                                 bnc->metric, bnc->path_count);
 455                                         if (detail)
 456                                                 for (nexthop = bnc->nexthop;
 457                                                      nexthop;
 458                                                      nexthop = nexthop->next)
 459                                                         switch (nexthop->type) {
 460                                                         case NEXTHOP_TYPE_IPV6:
 461                                                                 vty_out(vty,
 462                                                                         "  gate %s\n",
 463                                                                         inet_ntop(
 464                                                                                 AF_INET6,
 465                                                                                 &nexthop->gate
 466                                                                                          .ipv6,
 467                                                                                 buf,
 468                                                                                 sizeof(buf)));
 469                                                                 break;
 470                                                         case NEXTHOP_TYPE_IPV6_IFINDEX:
 471                                                                 vty_out(vty,
 472                                                                         "  gate %s, if %s\n",
 473                                                                         inet_ntop(
 474                                                                                 AF_INET6,
 475                                                                                 &nexthop->gate
 476                                                                                          .ipv6,
 477                                                                                 buf,
 478                                                                                 sizeof(buf)),
 479                                                                         ifindex2ifname(
 480                                                                                 nexthop->ifindex,
 481                                                                                 bgp->vrf_id));
 482                                                                 break;
 483                                                         case NEXTHOP_TYPE_IPV4:
 484                                                                 vty_out(vty,
 485                                                                         "  gate %s\n",
 486                                                                         inet_ntop(
 487                                                                                 AF_INET,
 488                                                                                 &nexthop->gate
 489                                                                                          .ipv4,
 490                                                                                 buf,
 491                                                                                 sizeof(buf)));
 492                                                                 break;
 493                                                         case NEXTHOP_TYPE_IFINDEX:
 494                                                                 vty_out(vty,
 495                                                                         "  if %s\n",
 496                                                                         ifindex2ifname(
 497                                                                                 nexthop->ifindex,
 498                                                                                 bgp->vrf_id));
 499                                                                 break;
 500                                                         case NEXTHOP_TYPE_IPV4_IFINDEX:
 501                                                                 vty_out(vty,
 502                                                                         "  gate %s, if %s\n",
 503                                                                         inet_ntop(
 504                                                                                 AF_INET,
 505                                                                                 &nexthop->gate
 506                                                                                          .ipv4,
 507                                                                                 buf,
 508                                                                                 sizeof(buf)),
 509                                                                         ifindex2ifname(
 510                                                                                 nexthop->ifindex,
 511                                                                                 bgp->vrf_id));
 512                                                                 break;
 513                                                         default:
 514                                                                 vty_out(vty,
 515                                                                         "  invalid nexthop type %u\n",
 516                                                                         nexthop->type);
 517                                                         }
 518                                 } else {
 519                                         vty_out(vty, " %s invalid\n",
 520                                                 inet_ntop(rn->p.family,
 521                                                           &rn->p.u.prefix, buf,
 522                                                           sizeof(buf)));
 523                                         if (CHECK_FLAG(bnc->flags,
 524                                                        BGP_NEXTHOP_CONNECTED))
 525                                                 vty_out(vty,
 526                                                         "  Must be Connected\n");
 527                                 }
 528                                 tbuf = time(NULL)
 529                                        - (bgp_clock() - bnc->last_update);
 530                                 vty_out(vty, "  Last update: %s", ctime(&tbuf));
 531                                 vty_out(vty, "\n");
 532                         }
 533                 }
 534         }
 535 }
 536
 537 static int show_ip_bgp_nexthop_table(struct vty *vty, const char *name,
 538                                      int detail)
 539 {
 540         struct bgp *bgp;
 541
 542         if (name)
 543                 bgp = bgp_lookup_by_name(name);
 544         else
 545                 bgp = bgp_get_default();
 546         if (!bgp) {
 547                 vty_out(vty, "%% No such BGP instance exist\n");
 548                 return CMD_WARNING;
 549         }
 550
 551         bgp_show_nexthops(vty, bgp, detail);
 552
 553         return CMD_SUCCESS;
 554 }
 555
 556 static void bgp_show_all_instances_nexthops_vty(struct vty *vty)
 557 {
 558         struct listnode *node, *nnode;
 559         struct bgp *bgp;
 560
 561         for (ALL_LIST_ELEMENTS(bm->bgp, node, nnode, bgp)) {
 562                 vty_out(vty, "\nInstance %s:\n",
 563                         (bgp->inst_type == BGP_INSTANCE_TYPE_DEFAULT)
 564                                 ? "Default"
 565                                 : bgp->name);
 566                 bgp_show_nexthops(vty, bgp, 0);
 567         }
 568 }
 569
 570 DEFUN (show_ip_bgp_nexthop,
 571        show_ip_bgp_nexthop_cmd,
 572        "show [ip] bgp [<view|vrf> VIEWVRFNAME] nexthop [detail]",
 573        SHOW_STR
 574        IP_STR
 575        BGP_STR
 576        BGP_INSTANCE_HELP_STR
 577        "BGP nexthop table\n"
 578        "Show detailed information\n")
 579 {
 580         int idx = 0;
 581         char *vrf = argv_find(argv, argc, "WORD", &idx) ? argv[idx]->arg : NULL;
 582         int detail = argv_find(argv, argc, "detail", &idx) ? 1 : 0;
 583         return show_ip_bgp_nexthop_table(vty, vrf, detail);
 584 }
 585
 586 DEFUN (show_ip_bgp_instance_all_nexthop,
 587        show_ip_bgp_instance_all_nexthop_cmd,
 588        "show [ip] bgp <view|vrf> all nexthop",
 589        SHOW_STR
 590        IP_STR
 591        BGP_STR
 592        BGP_INSTANCE_ALL_HELP_STR
 593        "BGP nexthop table\n")
 594 {
 595         bgp_show_all_instances_nexthops_vty(vty);
 596         return CMD_SUCCESS;
 597 }
 598
 599 void bgp_scan_init(struct bgp *bgp)
 600 {
 601         afi_t afi;
 602
 603         for (afi = AFI_IP; afi < AFI_MAX; afi++) {
 604                 bgp->nexthop_cache_table[afi] =
 605                         bgp_table_init(afi, SAFI_UNICAST);
 606                 bgp->connected_table[afi] = bgp_table_init(afi, SAFI_UNICAST);
 607                 bgp->import_check_table[afi] =
 608                         bgp_table_init(afi, SAFI_UNICAST);
 609         }
 610 }
 611
 612 void bgp_scan_vty_init(void)
 613 {
 614         install_element(VIEW_NODE, &show_ip_bgp_nexthop_cmd);
 615         install_element(VIEW_NODE, &show_ip_bgp_instance_all_nexthop_cmd);
 616 }
 617
 618 void bgp_scan_finish(struct bgp *bgp)
 619 {
 620         afi_t afi;
 621
 622         for (afi = AFI_IP; afi < AFI_MAX; afi++) {
 623                 /* Only the current one needs to be reset. */
 624                 bgp_nexthop_cache_reset(bgp->nexthop_cache_table[afi]);
 625                 bgp_table_unlock(bgp->nexthop_cache_table[afi]);
 626                 bgp->nexthop_cache_table[afi] = NULL;
 627
 628                 bgp_table_unlock(bgp->connected_table[afi]);
 629                 bgp->connected_table[afi] = NULL;
 630
 631                 bgp_table_unlock(bgp->import_check_table[afi]);
 632                 bgp->import_check_table[afi] = NULL;
 633         }
 634 }