bgpd/bgp_updgrp_adv.c

   1 /**
   2  * bgp_updgrp_adv.c: BGP update group advertisement and adjacency
   3  *                   maintenance
   4  *
   5  *
   6  * @copyright Copyright (C) 2014 Cumulus Networks, Inc.
   7  *
   8  * @author Avneesh Sachdev <avneesh@sproute.net>
   9  * @author Rajesh Varadarajan <rajesh@sproute.net>
  10  * @author Pradosh Mohapatra <pradosh@sproute.net>
  11  *
  12  * This file is part of GNU Zebra.
  13  *
  14  * GNU Zebra is free software; you can redistribute it and/or modify it
  15  * under the terms of the GNU General Public License as published by the
  16  * Free Software Foundation; either version 2, or (at your option) any
  17  * later version.
  18  *
  19  * GNU Zebra is distributed in the hope that it will be useful, but
  20  * WITHOUT ANY WARRANTY; without even the implied warranty of
  21  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  22  * General Public License for more details.
  23  *
  24  * You should have received a copy of the GNU General Public License along
  25  * with this program; see the file COPYING; if not, write to the Free Software
  26  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
  27  */
  28
  29 #include <zebra.h>
  30
  31 #include "command.h"
  32 #include "memory.h"
  33 #include "prefix.h"
  34 #include "hash.h"
  35 #include "thread.h"
  36 #include "queue.h"
  37 #include "routemap.h"
  38 #include "filter.h"
  39
  40 #include "bgpd/bgpd.h"
  41 #include "bgpd/bgp_table.h"
  42 #include "bgpd/bgp_debug.h"
  43 #include "bgpd/bgp_route.h"
  44 #include "bgpd/bgp_advertise.h"
  45 #include "bgpd/bgp_attr.h"
  46 #include "bgpd/bgp_aspath.h"
  47 #include "bgpd/bgp_packet.h"
  48 #include "bgpd/bgp_fsm.h"
  49 #include "bgpd/bgp_mplsvpn.h"
  50 #include "bgpd/bgp_updgrp.h"
  51 #include "bgpd/bgp_advertise.h"
  52 #include "bgpd/bgp_addpath.h"
  53
  54
  55 /********************
  56  * PRIVATE FUNCTIONS
  57  ********************/
  58 static int bgp_adj_out_compare(const struct bgp_adj_out *o1,
  59                                const struct bgp_adj_out *o2)
  60 {
  61         if (o1->subgroup < o2->subgroup)
  62                 return -1;
  63
  64         if (o1->subgroup > o2->subgroup)
  65                 return 1;
  66
  67         if (o1->addpath_tx_id < o2->addpath_tx_id)
  68                 return -1;
  69
  70         if (o1->addpath_tx_id > o2->addpath_tx_id)
  71                 return 1;
  72
  73         return 0;
  74 }
  75 RB_GENERATE(bgp_adj_out_rb, bgp_adj_out, adj_entry, bgp_adj_out_compare);
  76
  77 static inline struct bgp_adj_out *adj_lookup(struct bgp_dest *dest,
  78                                              struct update_subgroup *subgrp,
  79                                              uint32_t addpath_tx_id)
  80 {
  81         struct bgp_adj_out lookup;
  82
  83         if (!dest || !subgrp)
  84                 return NULL;
  85
  86         /* update-groups that do not support addpath will pass 0 for
  87          * addpath_tx_id. */
  88         lookup.subgroup = subgrp;
  89         lookup.addpath_tx_id = addpath_tx_id;
  90
  91         return RB_FIND(bgp_adj_out_rb, &dest->adj_out, &lookup);
  92 }
  93
  94 static void adj_free(struct bgp_adj_out *adj)
  95 {
  96         TAILQ_REMOVE(&(adj->subgroup->adjq), adj, subgrp_adj_train);
  97         SUBGRP_DECR_STAT(adj->subgroup, adj_count);
  98
  99         RB_REMOVE(bgp_adj_out_rb, &adj->dest->adj_out, adj);
 100         bgp_dest_unlock_node(adj->dest);
 101
 102         XFREE(MTYPE_BGP_ADJ_OUT, adj);
 103 }
 104
 105 static void subgrp_withdraw_stale_addpath(struct updwalk_context *ctx,
 106                                           struct update_subgroup *subgrp)
 107 {
 108         struct bgp_adj_out *adj, *adj_next;
 109         uint32_t id;
 110         struct bgp_path_info *pi;
 111         afi_t afi = SUBGRP_AFI(subgrp);
 112         safi_t safi = SUBGRP_SAFI(subgrp);
 113         struct peer *peer = SUBGRP_PEER(subgrp);
 114
 115         /* Look through all of the paths we have advertised for this rn and send
 116          * a withdraw for the ones that are no longer present */
 117         RB_FOREACH_SAFE (adj, bgp_adj_out_rb, &ctx->dest->adj_out, adj_next) {
 118
 119                 if (adj->subgroup == subgrp) {
 120                         for (pi = bgp_dest_get_bgp_path_info(ctx->dest); pi;
 121                              pi = pi->next) {
 122                                 id = bgp_addpath_id_for_peer(peer, afi, safi,
 123                                         &pi->tx_addpath);
 124
 125                                 if (id == adj->addpath_tx_id) {
 126                                         break;
 127                                 }
 128                         }
 129
 130                         if (!pi) {
 131                                 subgroup_process_announce_selected(
 132                                         subgrp, NULL, ctx->dest,
 133                                         adj->addpath_tx_id);
 134                         }
 135                 }
 136         }
 137 }
 138
 139 static int group_announce_route_walkcb(struct update_group *updgrp, void *arg)
 140 {
 141         struct updwalk_context *ctx = arg;
 142         struct update_subgroup *subgrp;
 143         struct bgp_path_info *pi;
 144         afi_t afi;
 145         safi_t safi;
 146         struct peer *peer;
 147         struct bgp_adj_out *adj, *adj_next;
 148         bool addpath_capable;
 149
 150         afi = UPDGRP_AFI(updgrp);
 151         safi = UPDGRP_SAFI(updgrp);
 152         peer = UPDGRP_PEER(updgrp);
 153         addpath_capable = bgp_addpath_encode_tx(peer, afi, safi);
 154
 155         if (BGP_DEBUG(update, UPDATE_OUT))
 156                 zlog_debug("%s: afi=%s, safi=%s, p=%pRN", __func__,
 157                            afi2str(afi), safi2str(safi),
 158                            bgp_dest_to_rnode(ctx->dest));
 159
 160         UPDGRP_FOREACH_SUBGRP (updgrp, subgrp) {
 161
 162                 /*
 163                  * Skip the subgroups that have coalesce timer running. We will
 164                  * walk the entire prefix table for those subgroups when the
 165                  * coalesce timer fires.
 166                  */
 167                 if (!subgrp->t_coalesce) {
 168                         /* An update-group that uses addpath */
 169                         if (addpath_capable) {
 170                                 subgrp_withdraw_stale_addpath(ctx, subgrp);
 171
 172                                 for (pi = bgp_dest_get_bgp_path_info(ctx->dest);
 173                                      pi; pi = pi->next) {
 174                                         /* Skip the bestpath for now */
 175                                         if (pi == ctx->pi)
 176                                                 continue;
 177
 178                                         subgroup_process_announce_selected(
 179                                                 subgrp, pi, ctx->dest,
 180                                                 bgp_addpath_id_for_peer(
 181                                                         peer, afi, safi,
 182                                                         &pi->tx_addpath));
 183                                 }
 184
 185                                 /* Process the bestpath last so the "show [ip]
 186                                  * bgp neighbor x.x.x.x advertised"
 187                                  * output shows the attributes from the bestpath
 188                                  */
 189                                 if (ctx->pi)
 190                                         subgroup_process_announce_selected(
 191                                                 subgrp, ctx->pi, ctx->dest,
 192                                                 bgp_addpath_id_for_peer(
 193                                                         peer, afi, safi,
 194                                                         &ctx->pi->tx_addpath));
 195                         }
 196
 197                         /* An update-group that does not use addpath */
 198                         else {
 199                                 if (ctx->pi) {
 200                                         subgroup_process_announce_selected(
 201                                                 subgrp, ctx->pi, ctx->dest,
 202                                                 bgp_addpath_id_for_peer(
 203                                                         peer, afi, safi,
 204                                                         &ctx->pi->tx_addpath));
 205                                 } else {
 206                                         /* Find the addpath_tx_id of the path we
 207                                          * had advertised and
 208                                          * send a withdraw */
 209                                         RB_FOREACH_SAFE (adj, bgp_adj_out_rb,
 210                                                          &ctx->dest->adj_out,
 211                                                          adj_next) {
 212                                                 if (adj->subgroup == subgrp) {
 213                                                         subgroup_process_announce_selected(
 214                                                                 subgrp, NULL,
 215                                                                 ctx->dest,
 216                                                                 adj->addpath_tx_id);
 217                                                 }
 218                                         }
 219                                 }
 220                         }
 221                 }
 222
 223                 /* Notify BGP Conditional advertisement */
 224                 bgp_notify_conditional_adv_scanner(subgrp);
 225         }
 226
 227         return UPDWALK_CONTINUE;
 228 }
 229
 230 static void subgrp_show_adjq_vty(struct update_subgroup *subgrp,
 231                                  struct vty *vty, uint8_t flags)
 232 {
 233         struct bgp_table *table;
 234         struct bgp_adj_out *adj;
 235         unsigned long output_count;
 236         struct bgp_dest *dest;
 237         int header1 = 1;
 238         struct bgp *bgp;
 239         int header2 = 1;
 240
 241         bgp = SUBGRP_INST(subgrp);
 242         if (!bgp)
 243                 return;
 244
 245         table = bgp->rib[SUBGRP_AFI(subgrp)][SUBGRP_SAFI(subgrp)];
 246
 247         output_count = 0;
 248
 249         for (dest = bgp_table_top(table); dest; dest = bgp_route_next(dest)) {
 250                 const struct prefix *dest_p = bgp_dest_get_prefix(dest);
 251
 252                 RB_FOREACH (adj, bgp_adj_out_rb, &dest->adj_out)
 253                         if (adj->subgroup == subgrp) {
 254                                 if (header1) {
 255                                         vty_out(vty,
 256                                                 "BGP table version is %" PRIu64
 257                                                 ", local router ID is %pI4\n",
 258                                                 table->version,
 259                                                 &bgp->router_id);
 260                                         vty_out(vty, BGP_SHOW_SCODE_HEADER);
 261                                         vty_out(vty, BGP_SHOW_OCODE_HEADER);
 262                                         header1 = 0;
 263                                 }
 264                                 if (header2) {
 265                                         vty_out(vty, BGP_SHOW_HEADER);
 266                                         header2 = 0;
 267                                 }
 268                                 if ((flags & UPDWALK_FLAGS_ADVQUEUE) && adj->adv
 269                                     && adj->adv->baa) {
 270                                         route_vty_out_tmp(vty, dest, dest_p,
 271                                                           adj->adv->baa->attr,
 272                                                           SUBGRP_SAFI(subgrp),
 273                                                           0, NULL, false);
 274                                         output_count++;
 275                                 }
 276                                 if ((flags & UPDWALK_FLAGS_ADVERTISED)
 277                                     && adj->attr) {
 278                                         route_vty_out_tmp(vty, dest, dest_p,
 279                                                           adj->attr,
 280                                                           SUBGRP_SAFI(subgrp),
 281                                                           0, NULL, false);
 282                                         output_count++;
 283                                 }
 284                         }
 285         }
 286         if (output_count != 0)
 287                 vty_out(vty, "\nTotal number of prefixes %ld\n", output_count);
 288 }
 289
 290 static int updgrp_show_adj_walkcb(struct update_group *updgrp, void *arg)
 291 {
 292         struct updwalk_context *ctx = arg;
 293         struct update_subgroup *subgrp;
 294         struct vty *vty;
 295
 296         vty = ctx->vty;
 297         UPDGRP_FOREACH_SUBGRP (updgrp, subgrp) {
 298                 if (ctx->subgrp_id && (ctx->subgrp_id != subgrp->id))
 299                         continue;
 300                 vty_out(vty, "update group %" PRIu64 ", subgroup %" PRIu64 "\n",
 301                         updgrp->id, subgrp->id);
 302                 subgrp_show_adjq_vty(subgrp, vty, ctx->flags);
 303         }
 304         return UPDWALK_CONTINUE;
 305 }
 306
 307 static void updgrp_show_adj(struct bgp *bgp, afi_t afi, safi_t safi,
 308                             struct vty *vty, uint64_t id, uint8_t flags)
 309 {
 310         struct updwalk_context ctx;
 311         memset(&ctx, 0, sizeof(ctx));
 312         ctx.vty = vty;
 313         ctx.subgrp_id = id;
 314         ctx.flags = flags;
 315
 316         update_group_af_walk(bgp, afi, safi, updgrp_show_adj_walkcb, &ctx);
 317 }
 318
 319 static int subgroup_coalesce_timer(struct thread *thread)
 320 {
 321         struct update_subgroup *subgrp;
 322         struct bgp *bgp;
 323
 324         subgrp = THREAD_ARG(thread);
 325         if (bgp_debug_update(NULL, NULL, subgrp->update_group, 0))
 326                 zlog_debug("u%" PRIu64 ":s%" PRIu64" announcing routes upon coalesce timer expiry(%u ms)",
 327                            (SUBGRP_UPDGRP(subgrp))->id, subgrp->id,
 328                            subgrp->v_coalesce);
 329         subgrp->t_coalesce = NULL;
 330         subgrp->v_coalesce = 0;
 331         bgp = SUBGRP_INST(subgrp);
 332         subgroup_announce_route(subgrp);
 333
 334
 335         /* While the announce_route() may kick off the route advertisement timer
 336          * for
 337          * the members of the subgroup, we'd like to send the initial updates
 338          * much
 339          * faster (i.e., without enforcing MRAI). Also, if there were no routes
 340          * to
 341          * announce, this is the method currently employed to trigger the EOR.
 342          */
 343         if (!bgp_update_delay_active(SUBGRP_INST(subgrp)) &&
 344             !(BGP_SUPPRESS_FIB_ENABLED(bgp))) {
 345                 struct peer_af *paf;
 346                 struct peer *peer;
 347
 348                 SUBGRP_FOREACH_PEER (subgrp, paf) {
 349                         peer = PAF_PEER(paf);
 350                         BGP_TIMER_OFF(peer->t_routeadv);
 351                         BGP_TIMER_ON(peer->t_routeadv, bgp_routeadv_timer, 0);
 352                 }
 353         }
 354
 355         return 0;
 356 }
 357
 358 static int update_group_announce_walkcb(struct update_group *updgrp, void *arg)
 359 {
 360         struct update_subgroup *subgrp;
 361
 362         UPDGRP_FOREACH_SUBGRP (updgrp, subgrp) {
 363                 subgroup_announce_all(subgrp);
 364         }
 365
 366         return UPDWALK_CONTINUE;
 367 }
 368
 369 static int update_group_announce_rrc_walkcb(struct update_group *updgrp,
 370                                             void *arg)
 371 {
 372         struct update_subgroup *subgrp;
 373         afi_t afi;
 374         safi_t safi;
 375         struct peer *peer;
 376
 377         afi = UPDGRP_AFI(updgrp);
 378         safi = UPDGRP_SAFI(updgrp);
 379         peer = UPDGRP_PEER(updgrp);
 380
 381         /* Only announce if this is a group of route-reflector-clients */
 382         if (CHECK_FLAG(peer->af_flags[afi][safi], PEER_FLAG_REFLECTOR_CLIENT)) {
 383                 UPDGRP_FOREACH_SUBGRP (updgrp, subgrp) {
 384                         subgroup_announce_all(subgrp);
 385                 }
 386         }
 387
 388         return UPDWALK_CONTINUE;
 389 }
 390
 391 /********************
 392  * PUBLIC FUNCTIONS
 393  ********************/
 394
 395 /**
 396  * Allocate an adj-out object. Do proper initialization of its fields,
 397  * primarily its association with the subgroup and the prefix.
 398  */
 399 struct bgp_adj_out *bgp_adj_out_alloc(struct update_subgroup *subgrp,
 400                                       struct bgp_dest *dest,
 401                                       uint32_t addpath_tx_id)
 402 {
 403         struct bgp_adj_out *adj;
 404
 405         adj = XCALLOC(MTYPE_BGP_ADJ_OUT, sizeof(struct bgp_adj_out));
 406         adj->subgroup = subgrp;
 407         adj->addpath_tx_id = addpath_tx_id;
 408
 409         RB_INSERT(bgp_adj_out_rb, &dest->adj_out, adj);
 410         bgp_dest_lock_node(dest);
 411         adj->dest = dest;
 412
 413         TAILQ_INSERT_TAIL(&(subgrp->adjq), adj, subgrp_adj_train);
 414         SUBGRP_INCR_STAT(subgrp, adj_count);
 415         return adj;
 416 }
 417
 418
 419 struct bgp_advertise *
 420 bgp_advertise_clean_subgroup(struct update_subgroup *subgrp,
 421                              struct bgp_adj_out *adj)
 422 {
 423         struct bgp_advertise *adv;
 424         struct bgp_advertise_attr *baa;
 425         struct bgp_advertise *next;
 426         struct bgp_adv_fifo_head *fhead;
 427
 428         adv = adj->adv;
 429         baa = adv->baa;
 430         next = NULL;
 431
 432         if (baa) {
 433                 fhead = &subgrp->sync->update;
 434
 435                 /* Unlink myself from advertise attribute FIFO.  */
 436                 bgp_advertise_delete(baa, adv);
 437
 438                 /* Fetch next advertise candidate. */
 439                 next = baa->adv;
 440
 441                 /* Unintern BGP advertise attribute.  */
 442                 bgp_advertise_unintern(subgrp->hash, baa);
 443         } else
 444                 fhead = &subgrp->sync->withdraw;
 445
 446
 447         /* Unlink myself from advertisement FIFO.  */
 448         bgp_adv_fifo_del(fhead, adv);
 449
 450         /* Free memory.  */
 451         bgp_advertise_free(adj->adv);
 452         adj->adv = NULL;
 453
 454         return next;
 455 }
 456
 457 void bgp_adj_out_set_subgroup(struct bgp_dest *dest,
 458                               struct update_subgroup *subgrp, struct attr *attr,
 459                               struct bgp_path_info *path)
 460 {
 461         struct bgp_adj_out *adj = NULL;
 462         struct bgp_advertise *adv;
 463         struct peer *peer;
 464         afi_t afi;
 465         safi_t safi;
 466         struct peer *adv_peer;
 467         struct peer_af *paf;
 468         struct bgp *bgp;
 469         uint32_t attr_hash = attrhash_key_make(attr);
 470
 471         peer = SUBGRP_PEER(subgrp);
 472         afi = SUBGRP_AFI(subgrp);
 473         safi = SUBGRP_SAFI(subgrp);
 474         bgp = SUBGRP_INST(subgrp);
 475
 476         if (DISABLE_BGP_ANNOUNCE)
 477                 return;
 478
 479         /* Look for adjacency information. */
 480         adj = adj_lookup(
 481                 dest, subgrp,
 482                 bgp_addpath_id_for_peer(peer, afi, safi, &path->tx_addpath));
 483
 484         if (adj) {
 485                 if (CHECK_FLAG(subgrp->sflags, SUBGRP_STATUS_TABLE_REPARSING))
 486                         subgrp->pscount++;
 487         } else {
 488                 adj = bgp_adj_out_alloc(
 489                         subgrp, dest,
 490                         bgp_addpath_id_for_peer(peer, afi, safi,
 491                                                 &path->tx_addpath));
 492                 if (!adj)
 493                         return;
 494
 495                 subgrp->pscount++;
 496         }
 497
 498         /* Check if we are sending the same route. This is needed to
 499          * avoid duplicate UPDATES. For instance, filtering communities
 500          * at egress, neighbors will see duplicate UPDATES despite
 501          * the route wasn't changed actually.
 502          * Do not suppress BGP UPDATES for route-refresh.
 503          */
 504         if (CHECK_FLAG(bgp->flags, BGP_FLAG_SUPPRESS_DUPLICATES)
 505             && !CHECK_FLAG(subgrp->sflags, SUBGRP_STATUS_FORCE_UPDATES)
 506             && adj->attr_hash == attr_hash) {
 507                 if (BGP_DEBUG(update, UPDATE_OUT)) {
 508                         char attr_str[BUFSIZ] = {0};
 509
 510                         bgp_dump_attr(attr, attr_str, sizeof(attr_str));
 511
 512                         zlog_debug("%s suppress UPDATE w/ attr: %s", peer->host,
 513                                    attr_str);
 514                 }
 515                 return;
 516         }
 517
 518         if (adj->adv)
 519                 bgp_advertise_clean_subgroup(subgrp, adj);
 520         adj->adv = bgp_advertise_new();
 521
 522         adv = adj->adv;
 523         adv->dest = dest;
 524         assert(adv->pathi == NULL);
 525         /* bgp_path_info adj_out reference */
 526         adv->pathi = bgp_path_info_lock(path);
 527
 528         adv->baa = bgp_advertise_intern(subgrp->hash, attr);
 529         adv->adj = adj;
 530         adj->attr_hash = attr_hash;
 531
 532         /* Add new advertisement to advertisement attribute list. */
 533         bgp_advertise_add(adv->baa, adv);
 534
 535         /*
 536          * If the update adv list is empty, trigger the member peers'
 537          * mrai timers so the socket writes can happen.
 538          */
 539         if (!bgp_adv_fifo_count(&subgrp->sync->update)) {
 540                 SUBGRP_FOREACH_PEER (subgrp, paf) {
 541                         /* If there are no routes in the withdraw list, set
 542                          * the flag PEER_STATUS_ADV_DELAY which will allow
 543                          * more routes to be sent in the update message
 544                          */
 545                         if (BGP_SUPPRESS_FIB_ENABLED(bgp)) {
 546                                 adv_peer = PAF_PEER(paf);
 547                                 if (!bgp_adv_fifo_count(
 548                                                 &subgrp->sync->withdraw))
 549                                         SET_FLAG(adv_peer->thread_flags,
 550                                                  PEER_THREAD_SUBGRP_ADV_DELAY);
 551                                 else
 552                                         UNSET_FLAG(adv_peer->thread_flags,
 553                                                 PEER_THREAD_SUBGRP_ADV_DELAY);
 554                         }
 555                         bgp_adjust_routeadv(PAF_PEER(paf));
 556                 }
 557         }
 558
 559         bgp_adv_fifo_add_tail(&subgrp->sync->update, adv);
 560
 561         subgrp->version = MAX(subgrp->version, dest->version);
 562 }
 563
 564 /* The only time 'withdraw' will be false is if we are sending
 565  * the "neighbor x.x.x.x default-originate" default and need to clear
 566  * bgp_adj_out for the 0.0.0.0/0 route in the BGP table.
 567  */
 568 void bgp_adj_out_unset_subgroup(struct bgp_dest *dest,
 569                                 struct update_subgroup *subgrp, char withdraw,
 570                                 uint32_t addpath_tx_id)
 571 {
 572         struct bgp_adj_out *adj;
 573         struct bgp_advertise *adv;
 574         bool trigger_write;
 575
 576         if (DISABLE_BGP_ANNOUNCE)
 577                 return;
 578
 579         /* Lookup existing adjacency */
 580         adj = adj_lookup(dest, subgrp, addpath_tx_id);
 581         if (adj != NULL) {
 582                 /* Clean up previous advertisement.  */
 583                 if (adj->adv)
 584                         bgp_advertise_clean_subgroup(subgrp, adj);
 585
 586                 /* If default originate is enabled and the route is default
 587                  * route, do not send withdraw. This will prevent deletion of
 588                  * the default route at the peer.
 589                  */
 590                 if (CHECK_FLAG(subgrp->sflags, SUBGRP_STATUS_DEFAULT_ORIGINATE)
 591                     && is_default_prefix(bgp_dest_get_prefix(dest)))
 592                         return;
 593
 594                 if (adj->attr && withdraw) {
 595                         /* We need advertisement structure.  */
 596                         adj->adv = bgp_advertise_new();
 597                         adv = adj->adv;
 598                         adv->dest = dest;
 599                         adv->adj = adj;
 600
 601                         /* Note if we need to trigger a packet write */
 602                         trigger_write =
 603                                 !bgp_adv_fifo_count(&subgrp->sync->withdraw);
 604
 605                         /* Add to synchronization entry for withdraw
 606                          * announcement.  */
 607                         bgp_adv_fifo_add_tail(&subgrp->sync->withdraw, adv);
 608
 609                         if (trigger_write)
 610                                 subgroup_trigger_write(subgrp);
 611                 } else {
 612                         /* Free allocated information.  */
 613                         adj_free(adj);
 614                 }
 615                 if (!CHECK_FLAG(subgrp->sflags, SUBGRP_STATUS_TABLE_REPARSING))
 616                         subgrp->pscount--;
 617         }
 618
 619         subgrp->version = MAX(subgrp->version, dest->version);
 620 }
 621
 622 void bgp_adj_out_remove_subgroup(struct bgp_dest *dest, struct bgp_adj_out *adj,
 623                                  struct update_subgroup *subgrp)
 624 {
 625         if (adj->attr)
 626                 bgp_attr_unintern(&adj->attr);
 627
 628         if (adj->adv)
 629                 bgp_advertise_clean_subgroup(subgrp, adj);
 630
 631         adj_free(adj);
 632 }
 633
 634 /*
 635  * Go through all the routes and clean up the adj/adv structures corresponding
 636  * to the subgroup.
 637  */
 638 void subgroup_clear_table(struct update_subgroup *subgrp)
 639 {
 640         struct bgp_adj_out *aout, *taout;
 641
 642         SUBGRP_FOREACH_ADJ_SAFE (subgrp, aout, taout)
 643                 bgp_adj_out_remove_subgroup(aout->dest, aout, subgrp);
 644 }
 645
 646 /*
 647  * subgroup_announce_table
 648  */
 649 void subgroup_announce_table(struct update_subgroup *subgrp,
 650                              struct bgp_table *table)
 651 {
 652         struct bgp_dest *dest;
 653         struct bgp_path_info *ri;
 654         struct attr attr;
 655         struct peer *peer;
 656         afi_t afi;
 657         safi_t safi;
 658         bool addpath_capable;
 659         struct bgp *bgp;
 660         bool advertise;
 661
 662         peer = SUBGRP_PEER(subgrp);
 663         afi = SUBGRP_AFI(subgrp);
 664         safi = SUBGRP_SAFI(subgrp);
 665         bgp = SUBGRP_INST(subgrp);
 666         addpath_capable = bgp_addpath_encode_tx(peer, afi, safi);
 667
 668         if (safi == SAFI_LABELED_UNICAST)
 669                 safi = SAFI_UNICAST;
 670
 671         if (!table)
 672                 table = peer->bgp->rib[afi][safi];
 673
 674         if (safi != SAFI_MPLS_VPN && safi != SAFI_ENCAP && safi != SAFI_EVPN
 675             && CHECK_FLAG(peer->af_flags[afi][safi],
 676                           PEER_FLAG_DEFAULT_ORIGINATE))
 677                 subgroup_default_originate(subgrp, 0);
 678
 679         subgrp->pscount = 0;
 680         SET_FLAG(subgrp->sflags, SUBGRP_STATUS_TABLE_REPARSING);
 681
 682         for (dest = bgp_table_top(table); dest; dest = bgp_route_next(dest)) {
 683                 const struct prefix *dest_p = bgp_dest_get_prefix(dest);
 684
 685                 /* Check if the route can be advertised */
 686                 advertise = bgp_check_advertise(bgp, dest);
 687
 688                 for (ri = bgp_dest_get_bgp_path_info(dest); ri; ri = ri->next)
 689
 690                         if (bgp_check_selected(ri, peer, addpath_capable, afi,
 691                                                safi)) {
 692                                 if (subgroup_announce_check(dest, ri, subgrp,
 693                                                             dest_p, &attr,
 694                                                             false)) {
 695                                         /* Check if route can be advertised */
 696                                         if (advertise) {
 697                                                 if (!bgp_check_withdrawal(bgp,
 698                                                                           dest))
 699                                                         bgp_adj_out_set_subgroup(
 700                                                                 dest, subgrp,
 701                                                                 &attr, ri);
 702                                                 else
 703                                                         bgp_adj_out_unset_subgroup(
 704                                                                 dest, subgrp, 1,
 705                                                                 bgp_addpath_id_for_peer(
 706                                                                         peer,
 707                                                                         afi,
 708                                                                         safi,
 709                                                                         &ri->tx_addpath));
 710                                         }
 711                                 } else {
 712                                         /* If default originate is enabled for
 713                                          * the peer, do not send explicit
 714                                          * withdraw. This will prevent deletion
 715                                          * of default route advertised through
 716                                          * default originate
 717                                          */
 718                                         if (CHECK_FLAG(
 719                                                     peer->af_flags[afi][safi],
 720                                                     PEER_FLAG_DEFAULT_ORIGINATE)
 721                                             && is_default_prefix(bgp_dest_get_prefix(dest)))
 722                                                 break;
 723
 724                                         bgp_adj_out_unset_subgroup(
 725                                                 dest, subgrp, 1,
 726                                                 bgp_addpath_id_for_peer(
 727                                                         peer, afi, safi,
 728                                                         &ri->tx_addpath));
 729                                 }
 730                         }
 731         }
 732         UNSET_FLAG(subgrp->sflags, SUBGRP_STATUS_TABLE_REPARSING);
 733
 734         /*
 735          * We walked through the whole table -- make sure our version number
 736          * is consistent with the one on the table. This should allow
 737          * subgroups to merge sooner if a peer comes up when the route node
 738          * with the largest version is no longer in the table. This also
 739          * covers the pathological case where all routes in the table have
 740          * now been deleted.
 741          */
 742         subgrp->version = MAX(subgrp->version, table->version);
 743
 744         /*
 745          * Start a task to merge the subgroup if necessary.
 746          */
 747         update_subgroup_trigger_merge_check(subgrp, 0);
 748 }
 749
 750 /*
 751  * subgroup_announce_route
 752  *
 753  * Refresh all routes out to a subgroup.
 754  */
 755 void subgroup_announce_route(struct update_subgroup *subgrp)
 756 {
 757         struct bgp_dest *dest;
 758         struct bgp_table *table;
 759         struct peer *onlypeer;
 760
 761         if (update_subgroup_needs_refresh(subgrp)) {
 762                 update_subgroup_set_needs_refresh(subgrp, 0);
 763         }
 764
 765         /*
 766          * First update is deferred until ORF or ROUTE-REFRESH is received
 767          */
 768         onlypeer = ((SUBGRP_PCOUNT(subgrp) == 1) ? (SUBGRP_PFIRST(subgrp))->peer
 769                                                  : NULL);
 770         if (onlypeer && CHECK_FLAG(onlypeer->af_sflags[SUBGRP_AFI(subgrp)]
 771                                                       [SUBGRP_SAFI(subgrp)],
 772                                    PEER_STATUS_ORF_WAIT_REFRESH))
 773                 return;
 774
 775         if (SUBGRP_SAFI(subgrp) != SAFI_MPLS_VPN
 776             && SUBGRP_SAFI(subgrp) != SAFI_ENCAP
 777             && SUBGRP_SAFI(subgrp) != SAFI_EVPN)
 778                 subgroup_announce_table(subgrp, NULL);
 779         else
 780                 for (dest = bgp_table_top(update_subgroup_rib(subgrp)); dest;
 781                      dest = bgp_route_next(dest)) {
 782                         table = bgp_dest_get_bgp_table_info(dest);
 783                         if (!table)
 784                                 continue;
 785                         subgroup_announce_table(subgrp, table);
 786                 }
 787 }
 788
 789 void subgroup_default_originate(struct update_subgroup *subgrp, int withdraw)
 790 {
 791         struct bgp *bgp;
 792         struct attr attr;
 793         struct attr *new_attr = &attr;
 794         struct prefix p;
 795         struct peer *from;
 796         struct bgp_dest *dest;
 797         struct bgp_path_info *pi;
 798         struct peer *peer;
 799         struct bgp_adj_out *adj;
 800         route_map_result_t ret = RMAP_DENYMATCH;
 801         afi_t afi;
 802         safi_t safi;
 803
 804         if (!subgrp)
 805                 return;
 806
 807         peer = SUBGRP_PEER(subgrp);
 808         afi = SUBGRP_AFI(subgrp);
 809         safi = SUBGRP_SAFI(subgrp);
 810
 811         if (!(afi == AFI_IP || afi == AFI_IP6))
 812                 return;
 813
 814         bgp = peer->bgp;
 815         from = bgp->peer_self;
 816
 817         bgp_attr_default_set(&attr, BGP_ORIGIN_IGP);
 818
 819         /* make coverity happy */
 820         assert(attr.aspath);
 821
 822         attr.local_pref = bgp->default_local_pref;
 823
 824         if ((afi == AFI_IP6) || peer_cap_enhe(peer, afi, safi)) {
 825                 /* IPv6 global nexthop must be included. */
 826                 attr.mp_nexthop_len = BGP_ATTR_NHLEN_IPV6_GLOBAL;
 827
 828                 /* If the peer is on shared nextwork and we have link-local
 829                    nexthop set it. */
 830                 if (peer->shared_network
 831                     && !IN6_IS_ADDR_UNSPECIFIED(&peer->nexthop.v6_local))
 832                         attr.mp_nexthop_len = BGP_ATTR_NHLEN_IPV6_GLOBAL_AND_LL;
 833         }
 834
 835         if (peer->default_rmap[afi][safi].name) {
 836                 struct bgp_path_info tmp_pi = {0};
 837
 838                 tmp_pi.peer = bgp->peer_self;
 839
 840                 SET_FLAG(bgp->peer_self->rmap_type, PEER_RMAP_TYPE_DEFAULT);
 841
 842                 /* Iterate over the RIB to see if we can announce
 843                  * the default route. We announce the default
 844                  * route only if route-map has a match.
 845                  */
 846                 for (dest = bgp_table_top(bgp->rib[afi][safi]); dest;
 847                      dest = bgp_route_next(dest)) {
 848                         if (!bgp_dest_has_bgp_path_info_data(dest))
 849                                 continue;
 850
 851                         for (pi = bgp_dest_get_bgp_path_info(dest); pi;
 852                              pi = pi->next) {
 853                                 struct attr tmp_attr = attr;
 854
 855                                 tmp_pi.attr = &tmp_attr;
 856
 857                                 ret = route_map_apply_ext(
 858                                         peer->default_rmap[afi][safi].map,
 859                                         bgp_dest_get_prefix(dest), pi, &tmp_pi);
 860
 861                                 if (ret == RMAP_DENYMATCH) {
 862                                         bgp_attr_undup(&tmp_attr, &attr);
 863                                         continue;
 864                                 } else {
 865                                         new_attr = bgp_attr_intern(&tmp_attr);
 866
 867                                         subgroup_announce_reset_nhop(
 868                                                 (peer_cap_enhe(peer, afi, safi)
 869                                                          ? AF_INET6
 870                                                          : AF_INET),
 871                                                 new_attr);
 872
 873                                         break;
 874                                 }
 875                         }
 876                         if (ret == RMAP_PERMITMATCH) {
 877                                 bgp_dest_unlock_node(dest);
 878                                 break;
 879                         }
 880                 }
 881                 bgp->peer_self->rmap_type = 0;
 882
 883                 if (ret == RMAP_DENYMATCH)
 884                         withdraw = 1;
 885         }
 886
 887         /* Check if the default route is in local BGP RIB which is
 888          * installed through redistribute or network command
 889          */
 890         memset(&p, 0, sizeof(p));
 891         p.family = afi2family(afi);
 892         p.prefixlen = 0;
 893         dest = bgp_afi_node_lookup(bgp->rib[afi][safi], afi, safi, &p, NULL);
 894
 895         if (withdraw) {
 896                 /* Withdraw the default route advertised using default
 897                  * originate
 898                  */
 899                 if (CHECK_FLAG(subgrp->sflags, SUBGRP_STATUS_DEFAULT_ORIGINATE))
 900                         subgroup_default_withdraw_packet(subgrp);
 901                 UNSET_FLAG(subgrp->sflags, SUBGRP_STATUS_DEFAULT_ORIGINATE);
 902
 903                 /* If default route is present in the local RIB, advertise the
 904                  * route
 905                  */
 906                 if (dest) {
 907                         for (pi = bgp_dest_get_bgp_path_info(dest); pi;
 908                              pi = pi->next) {
 909                                 if (CHECK_FLAG(pi->flags, BGP_PATH_SELECTED))
 910                                         if (subgroup_announce_check(
 911                                                     dest, pi, subgrp,
 912                                                     bgp_dest_get_prefix(dest),
 913                                                     &attr, false))
 914                                                 bgp_adj_out_set_subgroup(
 915                                                         dest, subgrp, &attr,
 916                                                         pi);
 917                         }
 918                         bgp_dest_unlock_node(dest);
 919                 }
 920         } else {
 921                 if (!CHECK_FLAG(subgrp->sflags,
 922                                 SUBGRP_STATUS_DEFAULT_ORIGINATE)) {
 923
 924                         /* The 'neighbor x.x.x.x default-originate' default will
 925                          * act as an
 926                          * implicit withdraw for any previous UPDATEs sent for
 927                          * 0.0.0.0/0 so
 928                          * clear adj_out for the 0.0.0.0/0 prefix in the BGP
 929                          * table.
 930                          */
 931                         if (dest) {
 932                                 /* Remove the adjacency for the previously
 933                                  * advertised default route
 934                                  */
 935                                 adj = adj_lookup(
 936                                        dest, subgrp,
 937                                        BGP_ADDPATH_TX_ID_FOR_DEFAULT_ORIGINATE);
 938                                 if (adj != NULL) {
 939                                         /* Clean up previous advertisement.  */
 940                                         if (adj->adv)
 941                                                 bgp_advertise_clean_subgroup(
 942                                                         subgrp, adj);
 943
 944                                         /* Free allocated information.  */
 945                                         adj_free(adj);
 946                                 }
 947                                 bgp_dest_unlock_node(dest);
 948                         }
 949
 950                         /* Advertise the default route */
 951                         if (bgp_in_graceful_shutdown(bgp))
 952                                 bgp_attr_add_gshut_community(new_attr);
 953
 954                         SET_FLAG(subgrp->sflags,
 955                                  SUBGRP_STATUS_DEFAULT_ORIGINATE);
 956                         subgroup_default_update_packet(subgrp, new_attr, from);
 957                 }
 958         }
 959
 960         aspath_unintern(&attr.aspath);
 961 }
 962
 963 /*
 964  * Announce the BGP table to a subgroup.
 965  *
 966  * At startup, we try to optimize route announcement by coalescing the
 967  * peer-up events. This is done only the first time - from then on,
 968  * subgrp->v_coalesce will be set to zero and the normal logic
 969  * prevails.
 970  */
 971 void subgroup_announce_all(struct update_subgroup *subgrp)
 972 {
 973         if (!subgrp)
 974                 return;
 975
 976         /*
 977          * If coalesce timer value is not set, announce routes immediately.
 978          */
 979         if (!subgrp->v_coalesce) {
 980                 if (bgp_debug_update(NULL, NULL, subgrp->update_group, 0))
 981                         zlog_debug("u%" PRIu64 ":s%" PRIu64" announcing all routes",
 982                                    subgrp->update_group->id, subgrp->id);
 983                 subgroup_announce_route(subgrp);
 984                 return;
 985         }
 986
 987         /*
 988          * We should wait for the coalesce timer. Arm the timer if not done.
 989          */
 990         if (!subgrp->t_coalesce) {
 991                 thread_add_timer_msec(bm->master, subgroup_coalesce_timer,
 992                                       subgrp, subgrp->v_coalesce,
 993                                       &subgrp->t_coalesce);
 994         }
 995 }
 996
 997 /*
 998  * Go through all update subgroups and set up the adv queue for the
 999  * input route.
1000  */
1001 void group_announce_route(struct bgp *bgp, afi_t afi, safi_t safi,
1002                           struct bgp_dest *dest, struct bgp_path_info *pi)
1003 {
1004         struct updwalk_context ctx;
1005         ctx.pi = pi;
1006         ctx.dest = dest;
1007
1008         /* If suppress fib is enabled, the route will be advertised when
1009          * FIB status is received
1010          */
1011         if (!bgp_check_advertise(bgp, dest))
1012                 return;
1013
1014         update_group_af_walk(bgp, afi, safi, group_announce_route_walkcb, &ctx);
1015 }
1016
1017 void update_group_show_adj_queue(struct bgp *bgp, afi_t afi, safi_t safi,
1018                                  struct vty *vty, uint64_t id)
1019 {
1020         updgrp_show_adj(bgp, afi, safi, vty, id, UPDWALK_FLAGS_ADVQUEUE);
1021 }
1022
1023 void update_group_show_advertised(struct bgp *bgp, afi_t afi, safi_t safi,
1024                                   struct vty *vty, uint64_t id)
1025 {
1026         updgrp_show_adj(bgp, afi, safi, vty, id, UPDWALK_FLAGS_ADVERTISED);
1027 }
1028
1029 void update_group_announce(struct bgp *bgp)
1030 {
1031         update_group_walk(bgp, update_group_announce_walkcb, NULL);
1032 }
1033
1034 void update_group_announce_rrclients(struct bgp *bgp)
1035 {
1036         update_group_walk(bgp, update_group_announce_rrc_walkcb, NULL);
1037 }