bfdd/ptm_adapter.c

   1 /*
   2  * BFD PTM adapter code
   3  * Copyright (C) 2018 Network Device Education Foundation, Inc. ("NetDEF")
   4  *
   5  * FRR is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License as published by the
   7  * Free Software Foundation; either version 2, or (at your option) any
   8  * later version.
   9  *
  10  * FRR is distributed in the hope that it will be useful, but
  11  * WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with FRR; see the file COPYING.  If not, write to the Free
  17  * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
  18  * 02111-1307, USA.
  19  */
  20
  21 #include <zebra.h>
  22
  23 #include "lib/libfrr.h"
  24 #include "lib/queue.h"
  25 #include "lib/stream.h"
  26 #include "lib/zclient.h"
  27
  28 #include "lib/bfd.h"
  29
  30 #include "bfd.h"
  31
  32 /*
  33  * Data structures
  34  */
  35 struct ptm_client_notification {
  36         struct bfd_session *pcn_bs;
  37         struct ptm_client *pcn_pc;
  38
  39         TAILQ_ENTRY(ptm_client_notification) pcn_entry;
  40 };
  41 TAILQ_HEAD(pcnqueue, ptm_client_notification);
  42
  43 struct ptm_client {
  44         uint32_t pc_pid;
  45         struct pcnqueue pc_pcnqueue;
  46
  47         TAILQ_ENTRY(ptm_client) pc_entry;
  48 };
  49 TAILQ_HEAD(pcqueue, ptm_client);
  50
  51 static struct pcqueue pcqueue;
  52 static struct zclient *zclient;
  53
  54
  55 /*
  56  * Prototypes
  57  */
  58 static int _ptm_msg_address(struct stream *msg, int family, const void *addr);
  59
  60 static void _ptm_msg_read_address(struct stream *msg, struct sockaddr_any *sa);
  61 static int _ptm_msg_read(struct stream *msg, int command, vrf_id_t vrf_id,
  62                          struct bfd_peer_cfg *bpc, struct ptm_client **pc);
  63
  64 static struct ptm_client *pc_lookup(uint32_t pid);
  65 static struct ptm_client *pc_new(uint32_t pid);
  66 static void pc_free(struct ptm_client *pc);
  67 static void pc_free_all(void);
  68 static struct ptm_client_notification *pcn_new(struct ptm_client *pc,
  69                                                struct bfd_session *bs);
  70 static struct ptm_client_notification *pcn_lookup(struct ptm_client *pc,
  71                                                   struct bfd_session *bs);
  72 static void pcn_free(struct ptm_client_notification *pcn);
  73
  74
  75 static void bfdd_dest_register(struct stream *msg, vrf_id_t vrf_id);
  76 static void bfdd_dest_deregister(struct stream *msg, vrf_id_t vrf_id);
  77 static void bfdd_client_register(struct stream *msg);
  78 static void bfdd_client_deregister(struct stream *msg);
  79
  80 /*
  81  * Functions
  82  */
  83 #ifdef BFD_DEBUG
  84 static void debug_printbpc(const char *func, unsigned int line,
  85                            struct bfd_peer_cfg *bpc);
  86
  87 static void debug_printbpc(const char *func, unsigned int line,
  88                            struct bfd_peer_cfg *bpc)
  89 {
  90         char addr[3][128];
  91         char timers[3][128];
  92         char cbit_str[10];
  93
  94         addr[0][0] = addr[1][0] = addr[2][0] = timers[0][0] = timers[1][0] =
  95                 timers[2][0] = 0;
  96
  97         snprintf(addr[0], sizeof(addr[0]), "peer:%s", satostr(&bpc->bpc_peer));
  98         if (bpc->bpc_local.sa_sin.sin_family)
  99                 snprintf(addr[1], sizeof(addr[1]), " local:%s",
 100                          satostr(&bpc->bpc_local));
 101
 102         if (bpc->bpc_has_localif)
 103                 snprintf(addr[2], sizeof(addr[2]), " ifname:%s",
 104                          bpc->bpc_localif);
 105
 106         if (bpc->bpc_has_vrfname)
 107                 snprintf(addr[2], sizeof(addr[2]), " vrf:%s", bpc->bpc_vrfname);
 108
 109         if (bpc->bpc_has_recvinterval)
 110                 snprintf(timers[0], sizeof(timers[0]), " rx:%lu",
 111                          bpc->bpc_recvinterval);
 112
 113         if (bpc->bpc_has_txinterval)
 114                 snprintf(timers[1], sizeof(timers[1]), " tx:%lu",
 115                          bpc->bpc_recvinterval);
 116
 117         if (bpc->bpc_has_detectmultiplier)
 118                 snprintf(timers[2], sizeof(timers[2]), " detect-multiplier:%d",
 119                          bpc->bpc_detectmultiplier);
 120
 121         sprintf(cbit_str, "CB %x", bpc->bpc_cbit);
 122
 123         log_debug("%s:%d: %s %s%s%s%s%s%s %s", func, line,
 124                   bpc->bpc_mhop ? "multi-hop" : "single-hop", addr[0], addr[1],
 125                   addr[2], timers[0], timers[1], timers[2], cbit_str);
 126 }
 127
 128 #define DEBUG_PRINTBPC(bpc) debug_printbpc(__FILE__, __LINE__, (bpc))
 129 #else
 130 #define DEBUG_PRINTBPC(bpc)
 131 #endif /* BFD_DEBUG */
 132
 133 static int _ptm_msg_address(struct stream *msg, int family, const void *addr)
 134 {
 135         stream_putc(msg, family);
 136
 137         switch (family) {
 138         case AF_INET:
 139                 stream_put(msg, addr, sizeof(struct in_addr));
 140                 stream_putc(msg, 32);
 141                 break;
 142
 143         case AF_INET6:
 144                 stream_put(msg, addr, sizeof(struct in6_addr));
 145                 stream_putc(msg, 128);
 146                 break;
 147
 148         default:
 149                 assert(0);
 150                 break;
 151         }
 152
 153         return 0;
 154 }
 155
 156 int ptm_bfd_notify(struct bfd_session *bs)
 157 {
 158         struct stream *msg;
 159
 160         bs->stats.znotification++;
 161
 162         /*
 163          * Message format:
 164          * - header: command, vrf
 165          * - l: interface index
 166          * - c: family
 167          *   - AF_INET:
 168          *     - 4 bytes: ipv4
 169          *   - AF_INET6:
 170          *     - 16 bytes: ipv6
 171          *   - c: prefix length
 172          * - l: bfd status
 173          * - c: family
 174          *   - AF_INET:
 175          *     - 4 bytes: ipv4
 176          *   - AF_INET6:
 177          *     - 16 bytes: ipv6
 178          *   - c: prefix length
 179          * - c: cbit
 180          *
 181          * Commands: ZEBRA_BFD_DEST_REPLAY
 182          *
 183          * q(64), l(32), w(16), c(8)
 184          */
 185         msg = zclient->obuf;
 186         stream_reset(msg);
 187
 188         /* TODO: VRF handling */
 189         if (bs->vrf)
 190                 zclient_create_header(msg, ZEBRA_BFD_DEST_REPLAY, bs->vrf->vrf_id);
 191         else
 192                 zclient_create_header(msg, ZEBRA_BFD_DEST_REPLAY, VRF_DEFAULT);
 193
 194         /* This header will be handled by `zebra_ptm.c`. */
 195         stream_putl(msg, ZEBRA_INTERFACE_BFD_DEST_UPDATE);
 196
 197         /* NOTE: Interface is a shortcut to avoid comparing source address. */
 198         if (bs->ifp != NULL)
 199                 stream_putl(msg, bs->ifp->ifindex);
 200         else
 201                 stream_putl(msg, IFINDEX_INTERNAL);
 202
 203         /* BFD destination prefix information. */
 204         _ptm_msg_address(msg, bs->key.family, &bs->key.peer);
 205
 206         /* BFD status */
 207         switch (bs->ses_state) {
 208         case PTM_BFD_UP:
 209                 stream_putl(msg, BFD_STATUS_UP);
 210                 break;
 211
 212         case PTM_BFD_ADM_DOWN:
 213         case PTM_BFD_DOWN:
 214         case PTM_BFD_INIT:
 215                 stream_putl(msg, BFD_STATUS_DOWN);
 216                 break;
 217
 218         default:
 219                 stream_putl(msg, BFD_STATUS_UNKNOWN);
 220                 break;
 221         }
 222
 223         /* BFD source prefix information. */
 224         _ptm_msg_address(msg, bs->key.family, &bs->key.local);
 225
 226         stream_putc(msg, bs->remote_cbit);
 227
 228         /* Write packet size. */
 229         stream_putw_at(msg, 0, stream_get_endp(msg));
 230
 231         return zclient_send_message(zclient);
 232 }
 233
 234 static void _ptm_msg_read_address(struct stream *msg, struct sockaddr_any *sa)
 235 {
 236         uint16_t family;
 237
 238         STREAM_GETW(msg, family);
 239
 240         switch (family) {
 241         case AF_INET:
 242                 sa->sa_sin.sin_family = family;
 243                 STREAM_GET(&sa->sa_sin.sin_addr, msg,
 244                            sizeof(sa->sa_sin.sin_addr));
 245 #ifdef HAVE_STRUCT_SOCKADDR_SA_LEN
 246                 sa->sa_sin.sin_len = sizeof(sa->sa_sin);
 247 #endif /* HAVE_STRUCT_SOCKADDR_SA_LEN */
 248                 return;
 249
 250         case AF_INET6:
 251                 sa->sa_sin6.sin6_family = family;
 252                 STREAM_GET(&sa->sa_sin6.sin6_addr, msg,
 253                            sizeof(sa->sa_sin6.sin6_addr));
 254 #ifdef HAVE_STRUCT_SOCKADDR_SA_LEN
 255                 sa->sa_sin6.sin6_len = sizeof(sa->sa_sin6);
 256 #endif /* HAVE_STRUCT_SOCKADDR_SA_LEN */
 257                 return;
 258
 259         default:
 260                 log_warning("ptm-read-address: invalid family: %d", family);
 261                 break;
 262         }
 263
 264 stream_failure:
 265         memset(sa, 0, sizeof(*sa));
 266 }
 267
 268 static int _ptm_msg_read(struct stream *msg, int command, vrf_id_t vrf_id,
 269                          struct bfd_peer_cfg *bpc, struct ptm_client **pc)
 270 {
 271         uint32_t pid;
 272         uint8_t ttl __attribute__((unused));
 273         size_t ifnamelen;
 274
 275         /*
 276          * Register/Deregister/Update Message format:
 277          * - header: Command, VRF
 278          * - l: pid
 279          * - w: family
 280          *   - AF_INET:
 281          *     - l: destination ipv4
 282          *   - AF_INET6:
 283          *     - 16 bytes: destination IPv6
 284          * - command != ZEBRA_BFD_DEST_DEREGISTER
 285          *   - l: min_rx
 286          *   - l: min_tx
 287          *   - c: detect multiplier
 288          * - c: is_multihop?
 289          *   - multihop:
 290          *     - w: family
 291          *       - AF_INET:
 292          *         - l: destination ipv4
 293          *       - AF_INET6:
 294          *         - 16 bytes: destination IPv6
 295          *     - c: ttl
 296          *   - no multihop
 297          *     - AF_INET6:
 298          *       - w: family
 299          *       - 16 bytes: ipv6 address
 300          *     - c: ifname length
 301          *     - X bytes: interface name
 302          * - c: bfd_cbit
 303          *
 304          * q(64), l(32), w(16), c(8)
 305          */
 306
 307         /* Initialize parameters return values. */
 308         memset(bpc, 0, sizeof(*bpc));
 309         *pc = NULL;
 310
 311         /* Find or allocate process context data. */
 312         STREAM_GETL(msg, pid);
 313
 314         *pc = pc_new(pid);
 315         if (*pc == NULL) {
 316                 log_debug("ptm-read: failed to allocate memory");
 317                 return -1;
 318         }
 319
 320         /* Register/update peer information. */
 321         _ptm_msg_read_address(msg, &bpc->bpc_peer);
 322
 323         /* Determine IP type from peer destination. */
 324         bpc->bpc_ipv4 = (bpc->bpc_peer.sa_sin.sin_family == AF_INET);
 325
 326         /* Get peer configuration. */
 327         if (command != ZEBRA_BFD_DEST_DEREGISTER) {
 328                 STREAM_GETL(msg, bpc->bpc_recvinterval);
 329                 bpc->bpc_has_recvinterval =
 330                         (bpc->bpc_recvinterval != BPC_DEF_RECEIVEINTERVAL);
 331
 332                 STREAM_GETL(msg, bpc->bpc_txinterval);
 333                 bpc->bpc_has_txinterval =
 334                         (bpc->bpc_txinterval != BPC_DEF_TRANSMITINTERVAL);
 335
 336                 STREAM_GETC(msg, bpc->bpc_detectmultiplier);
 337                 bpc->bpc_has_detectmultiplier =
 338                         (bpc->bpc_detectmultiplier != BPC_DEF_DETECTMULTIPLIER);
 339         }
 340
 341         /* Read (single|multi)hop and its options. */
 342         STREAM_GETC(msg, bpc->bpc_mhop);
 343         if (bpc->bpc_mhop) {
 344                 /* Read multihop source address and TTL. */
 345                 _ptm_msg_read_address(msg, &bpc->bpc_local);
 346                 STREAM_GETC(msg, ttl);
 347         } else {
 348                 /* If target is IPv6, then we must obtain local address. */
 349                 if (bpc->bpc_ipv4 == false)
 350                         _ptm_msg_read_address(msg, &bpc->bpc_local);
 351
 352                 /*
 353                  * Read interface name and make sure it fits our data
 354                  * structure, otherwise fail.
 355                  */
 356                 STREAM_GETC(msg, ifnamelen);
 357                 if (ifnamelen >= sizeof(bpc->bpc_localif)) {
 358                         log_error("ptm-read: interface name is too big");
 359                         return -1;
 360                 }
 361
 362                 bpc->bpc_has_localif = ifnamelen > 0;
 363                 if (bpc->bpc_has_localif) {
 364                         STREAM_GET(bpc->bpc_localif, msg, ifnamelen);
 365                         bpc->bpc_localif[ifnamelen] = 0;
 366                 }
 367         }
 368         if (vrf_id != VRF_DEFAULT) {
 369                 struct vrf *vrf;
 370
 371                 vrf = vrf_lookup_by_id(vrf_id);
 372                 if (vrf) {
 373                         bpc->bpc_has_vrfname = true;
 374                         strlcpy(bpc->bpc_vrfname, vrf->name, sizeof(bpc->bpc_vrfname));
 375                 } else {
 376                         log_error("ptm-read: vrf id %u could not be identified", vrf_id);
 377                         return -1;
 378                 }
 379         } else {
 380                 bpc->bpc_has_vrfname = true;
 381                 strlcpy(bpc->bpc_vrfname, VRF_DEFAULT_NAME, sizeof(bpc->bpc_vrfname));
 382         }
 383
 384         STREAM_GETC(msg, bpc->bpc_cbit);
 385
 386         /* Sanity check: peer and local address must match IP types. */
 387         if (bpc->bpc_local.sa_sin.sin_family != 0
 388             && (bpc->bpc_local.sa_sin.sin_family
 389                 != bpc->bpc_peer.sa_sin.sin_family)) {
 390                 log_warning("ptm-read: peer family doesn't match local type");
 391                 return -1;
 392         }
 393
 394         return 0;
 395
 396 stream_failure:
 397         return -1;
 398 }
 399
 400 static void bfdd_dest_register(struct stream *msg, vrf_id_t vrf_id)
 401 {
 402         struct ptm_client *pc;
 403         struct ptm_client_notification *pcn;
 404         struct bfd_session *bs;
 405         struct bfd_peer_cfg bpc;
 406
 407         /* Read the client context and peer data. */
 408         if (_ptm_msg_read(msg, ZEBRA_BFD_DEST_REGISTER, vrf_id, &bpc, &pc) == -1)
 409                 return;
 410
 411         DEBUG_PRINTBPC(&bpc);
 412
 413         /* Find or start new BFD session. */
 414         bs = bs_peer_find(&bpc);
 415         if (bs == NULL) {
 416                 bs = ptm_bfd_sess_new(&bpc);
 417                 if (bs == NULL) {
 418                         log_debug("ptm-add-dest: failed to create BFD session");
 419                         return;
 420                 }
 421         } else {
 422                 /* Don't try to change echo/shutdown state. */
 423                 bpc.bpc_echo = BFD_CHECK_FLAG(bs->flags, BFD_SESS_FLAG_ECHO);
 424                 bpc.bpc_shutdown =
 425                         BFD_CHECK_FLAG(bs->flags, BFD_SESS_FLAG_SHUTDOWN);
 426         }
 427
 428         /* Create client peer notification register. */
 429         pcn = pcn_new(pc, bs);
 430         if (pcn == NULL) {
 431                 log_error("ptm-add-dest: failed to registrate notifications");
 432                 return;
 433         }
 434
 435         ptm_bfd_notify(bs);
 436 }
 437
 438 static void bfdd_dest_deregister(struct stream *msg, vrf_id_t vrf_id)
 439 {
 440         struct ptm_client *pc;
 441         struct ptm_client_notification *pcn;
 442         struct bfd_session *bs;
 443         struct bfd_peer_cfg bpc;
 444
 445         /* Read the client context and peer data. */
 446         if (_ptm_msg_read(msg, ZEBRA_BFD_DEST_DEREGISTER, vrf_id, &bpc, &pc) == -1)
 447                 return;
 448
 449         DEBUG_PRINTBPC(&bpc);
 450
 451         /* Find or start new BFD session. */
 452         bs = bs_peer_find(&bpc);
 453         if (bs == NULL) {
 454                 log_debug("ptm-del-dest: failed to find BFD session");
 455                 return;
 456         }
 457
 458         /* Unregister client peer notification. */
 459         pcn = pcn_lookup(pc, bs);
 460         pcn_free(pcn);
 461         if (bs->refcount ||
 462             BFD_CHECK_FLAG(bs->flags, BFD_SESS_FLAG_CONFIG))
 463                 return;
 464         ptm_bfd_sess_del(&bpc);
 465 }
 466
 467 /*
 468  * header: command, VRF
 469  * l: pid
 470  */
 471 static void bfdd_client_register(struct stream *msg)
 472 {
 473         struct ptm_client *pc;
 474         uint32_t pid;
 475
 476         /* Find or allocate process context data. */
 477         STREAM_GETL(msg, pid);
 478
 479         pc = pc_new(pid);
 480         if (pc == NULL) {
 481                 log_error("ptm-add-client: failed to register client: %u", pid);
 482                 return;
 483         }
 484
 485         return;
 486
 487 stream_failure:
 488         log_error("ptm-add-client: failed to register client");
 489 }
 490
 491 /*
 492  * header: command, VRF
 493  * l: pid
 494  */
 495 static void bfdd_client_deregister(struct stream *msg)
 496 {
 497         struct ptm_client *pc;
 498         uint32_t pid;
 499
 500         /* Find or allocate process context data. */
 501         STREAM_GETL(msg, pid);
 502
 503         pc = pc_lookup(pid);
 504         if (pc == NULL) {
 505                 log_debug("ptm-del-client: failed to find client: %u", pid);
 506                 return;
 507         }
 508
 509         pc_free(pc);
 510
 511         return;
 512
 513 stream_failure:
 514         log_error("ptm-del-client: failed to deregister client");
 515 }
 516
 517 static int bfdd_replay(ZAPI_CALLBACK_ARGS)
 518 {
 519         struct stream *msg = zclient->ibuf;
 520         uint32_t rcmd;
 521
 522         STREAM_GETL(msg, rcmd);
 523
 524         switch (rcmd) {
 525         case ZEBRA_BFD_DEST_REGISTER:
 526         case ZEBRA_BFD_DEST_UPDATE:
 527                 bfdd_dest_register(msg, vrf_id);
 528                 break;
 529         case ZEBRA_BFD_DEST_DEREGISTER:
 530                 bfdd_dest_deregister(msg, vrf_id);
 531                 break;
 532         case ZEBRA_BFD_CLIENT_REGISTER:
 533                 bfdd_client_register(msg);
 534                 break;
 535         case ZEBRA_BFD_CLIENT_DEREGISTER:
 536                 bfdd_client_deregister(msg);
 537                 break;
 538
 539         default:
 540                 log_debug("ptm-replay: invalid message type %u", rcmd);
 541                 return -1;
 542         }
 543
 544         return 0;
 545
 546 stream_failure:
 547         log_error("ptm-replay: failed to find command");
 548         return -1;
 549 }
 550
 551 static void bfdd_zebra_connected(struct zclient *zc)
 552 {
 553         struct stream *msg = zc->obuf;
 554
 555         /* Clean-up and free ptm clients data memory. */
 556         pc_free_all();
 557
 558         /*
 559          * The replay is an empty message just to trigger client daemons
 560          * configuration replay.
 561          */
 562         stream_reset(msg);
 563         zclient_create_header(msg, ZEBRA_BFD_DEST_REPLAY, VRF_DEFAULT);
 564         stream_putl(msg, ZEBRA_BFD_DEST_REPLAY);
 565         stream_putw_at(msg, 0, stream_get_endp(msg));
 566
 567         /* Ask for interfaces information. */
 568         zclient_create_header(msg, ZEBRA_INTERFACE_ADD, VRF_DEFAULT);
 569
 570         /* Send requests. */
 571         zclient_send_message(zclient);
 572 }
 573
 574 static void bfdd_sessions_enable_interface(struct interface *ifp)
 575 {
 576         struct bfd_session_observer *bso;
 577         struct bfd_session *bs;
 578         struct vrf *vrf;
 579
 580         TAILQ_FOREACH(bso, &bglobal.bg_obslist, bso_entry) {
 581                 bs = bso->bso_bs;
 582                 if (bso->bso_isinterface == false)
 583                         continue;
 584                 /* Interface name mismatch. */
 585                 if (strcmp(ifp->name, bs->key.ifname))
 586                         continue;
 587                 vrf = vrf_lookup_by_id(ifp->vrf_id);
 588                 if (!vrf)
 589                         continue;
 590                 if (bs->key.vrfname[0] &&
 591                     strcmp(vrf->name, bs->key.vrfname))
 592                         continue;
 593                 /* Skip enabled sessions. */
 594                 if (bs->sock != -1)
 595                         continue;
 596
 597                 /* Try to enable it. */
 598                 bfd_session_enable(bs);
 599         }
 600 }
 601
 602 static void bfdd_sessions_disable_interface(struct interface *ifp)
 603 {
 604         struct bfd_session_observer *bso;
 605         struct bfd_session *bs;
 606
 607         TAILQ_FOREACH(bso, &bglobal.bg_obslist, bso_entry) {
 608                 if (bso->bso_isinterface == false)
 609                         continue;
 610
 611                 /* Interface name mismatch. */
 612                 bs = bso->bso_bs;
 613                 if (strcmp(ifp->name, bs->key.ifname))
 614                         continue;
 615                 /* Skip disabled sessions. */
 616                 if (bs->sock == -1)
 617                         continue;
 618
 619                 /* Try to enable it. */
 620                 bfd_session_disable(bs);
 621
 622         }
 623 }
 624
 625 void bfdd_sessions_enable_vrf(struct vrf *vrf)
 626 {
 627         struct bfd_session_observer *bso;
 628         struct bfd_session *bs;
 629
 630         /* it may affect configs without interfaces */
 631         TAILQ_FOREACH(bso, &bglobal.bg_obslist, bso_entry) {
 632                 bs = bso->bso_bs;
 633                 /* update name */
 634                 if (bs->vrf && bs->vrf == vrf) {
 635                         if (!strmatch(bs->key.vrfname, vrf->name))
 636                                 bfd_session_update_vrf_name(bs, vrf);
 637                 }
 638                 if (bs->vrf)
 639                         continue;
 640                 if (bs->key.vrfname[0] &&
 641                     strcmp(vrf->name, bs->key.vrfname))
 642                         continue;
 643                 /* need to update the vrf information on
 644                  * bs so that callbacks are handled
 645                  */
 646                 bs->vrf = vrf;
 647                 /* Skip enabled sessions. */
 648                 if (bs->sock != -1)
 649                         continue;
 650                 /* Try to enable it. */
 651                 bfd_session_enable(bs);
 652         }
 653 }
 654
 655 void bfdd_sessions_disable_vrf(struct vrf *vrf)
 656 {
 657         struct bfd_session_observer *bso;
 658         struct bfd_session *bs;
 659
 660         TAILQ_FOREACH(bso, &bglobal.bg_obslist, bso_entry) {
 661                 if (bso->bso_isinterface)
 662                         continue;
 663                 bs = bso->bso_bs;
 664                 if (bs->key.vrfname[0] &&
 665                     strcmp(vrf->name, bs->key.vrfname))
 666                         continue;
 667                 /* Skip disabled sessions. */
 668                 if (bs->sock == -1)
 669                         continue;
 670
 671                 /* Try to enable it. */
 672                 bfd_session_disable(bs);
 673         }
 674 }
 675
 676 static int bfd_ifp_destroy(struct interface *ifp)
 677 {
 678         bfdd_sessions_disable_interface(ifp);
 679
 680         return 0;
 681 }
 682
 683 static int bfdd_interface_vrf_update(ZAPI_CALLBACK_ARGS)
 684 {
 685         struct interface *ifp;
 686         vrf_id_t nvrfid;
 687
 688         ifp = zebra_interface_vrf_update_read(zclient->ibuf, vrf_id, &nvrfid);
 689         if (ifp == NULL)
 690                 return 0;
 691
 692         if_update_to_new_vrf(ifp, nvrfid);
 693
 694         return 0;
 695 }
 696
 697 static void bfdd_sessions_enable_address(struct connected *ifc)
 698 {
 699         struct bfd_session_observer *bso;
 700         struct bfd_session *bs;
 701         struct prefix prefix;
 702
 703         TAILQ_FOREACH(bso, &bglobal.bg_obslist, bso_entry) {
 704                 if (bso->bso_isaddress == false)
 705                         continue;
 706
 707                 /* Skip enabled sessions. */
 708                 bs = bso->bso_bs;
 709                 if (bs->sock != -1)
 710                         continue;
 711
 712                 /* Check address. */
 713                 prefix = bso->bso_addr;
 714                 prefix.prefixlen = ifc->address->prefixlen;
 715                 if (prefix_cmp(&prefix, ifc->address))
 716                         continue;
 717
 718                 /* Try to enable it. */
 719                 bfd_session_enable(bs);
 720         }
 721 }
 722
 723 static int bfdd_interface_address_update(ZAPI_CALLBACK_ARGS)
 724 {
 725         struct connected *ifc;
 726
 727         ifc = zebra_interface_address_read(cmd, zclient->ibuf, vrf_id);
 728         if (ifc == NULL)
 729                 return 0;
 730
 731         bfdd_sessions_enable_address(ifc);
 732
 733         return 0;
 734 }
 735
 736 static int bfd_ifp_create(struct interface *ifp)
 737 {
 738         bfdd_sessions_enable_interface(ifp);
 739
 740         return 0;
 741 }
 742
 743 void bfdd_zclient_init(struct zebra_privs_t *bfdd_priv)
 744 {
 745         if_zapi_callbacks(bfd_ifp_create, NULL, NULL, bfd_ifp_destroy);
 746         zclient = zclient_new(master, &zclient_options_default);
 747         assert(zclient != NULL);
 748         zclient_init(zclient, ZEBRA_ROUTE_BFD, 0, bfdd_priv);
 749
 750         /*
 751          * We'll receive all messages through replay, however it will
 752          * contain a special field with the real command inside so we
 753          * avoid having to create too many handlers.
 754          */
 755         zclient->bfd_dest_replay = bfdd_replay;
 756
 757         /* Send replay request on zebra connect. */
 758         zclient->zebra_connected = bfdd_zebra_connected;
 759
 760         /* Learn about interface VRF. */
 761         zclient->interface_vrf_update = bfdd_interface_vrf_update;
 762
 763         /* Learn about new addresses being registered. */
 764         zclient->interface_address_add = bfdd_interface_address_update;
 765         zclient->interface_address_delete = bfdd_interface_address_update;
 766 }
 767
 768 void bfdd_zclient_register(vrf_id_t vrf_id)
 769 {
 770         if (!zclient || zclient->sock < 0)
 771                 return;
 772         zclient_send_reg_requests(zclient, vrf_id);
 773 }
 774
 775 void bfdd_zclient_unregister(vrf_id_t vrf_id)
 776 {
 777         if (!zclient || zclient->sock < 0)
 778                 return;
 779         zclient_send_dereg_requests(zclient, vrf_id);
 780 }
 781
 782 void bfdd_zclient_stop(void)
 783 {
 784         zclient_stop(zclient);
 785
 786         /* Clean-up and free ptm clients data memory. */
 787         pc_free_all();
 788 }
 789
 790
 791 /*
 792  * Client handling.
 793  */
 794 static struct ptm_client *pc_lookup(uint32_t pid)
 795 {
 796         struct ptm_client *pc;
 797
 798         TAILQ_FOREACH (pc, &pcqueue, pc_entry) {
 799                 if (pc->pc_pid != pid)
 800                         continue;
 801
 802                 break;
 803         }
 804
 805         return pc;
 806 }
 807
 808 static struct ptm_client *pc_new(uint32_t pid)
 809 {
 810         struct ptm_client *pc;
 811
 812         /* Look up first, if not found create the client. */
 813         pc = pc_lookup(pid);
 814         if (pc != NULL)
 815                 return pc;
 816
 817         /* Allocate the client data and save it. */
 818         pc = XCALLOC(MTYPE_BFDD_CONTROL, sizeof(*pc));
 819
 820         pc->pc_pid = pid;
 821         TAILQ_INSERT_HEAD(&pcqueue, pc, pc_entry);
 822         return pc;
 823 }
 824
 825 static void pc_free(struct ptm_client *pc)
 826 {
 827         struct ptm_client_notification *pcn;
 828
 829         if (pc == NULL)
 830                 return;
 831
 832         TAILQ_REMOVE(&pcqueue, pc, pc_entry);
 833
 834         while (!TAILQ_EMPTY(&pc->pc_pcnqueue)) {
 835                 pcn = TAILQ_FIRST(&pc->pc_pcnqueue);
 836                 pcn_free(pcn);
 837         }
 838
 839         XFREE(MTYPE_BFDD_CONTROL, pc);
 840 }
 841
 842 static void pc_free_all(void)
 843 {
 844         struct ptm_client *pc;
 845
 846         while (!TAILQ_EMPTY(&pcqueue)) {
 847                 pc = TAILQ_FIRST(&pcqueue);
 848                 pc_free(pc);
 849         }
 850 }
 851
 852 static struct ptm_client_notification *pcn_new(struct ptm_client *pc,
 853                                                struct bfd_session *bs)
 854 {
 855         struct ptm_client_notification *pcn;
 856
 857         /* Try to find an existing pcn fist. */
 858         pcn = pcn_lookup(pc, bs);
 859         if (pcn != NULL)
 860                 return pcn;
 861
 862         /* Save the client notification data. */
 863         pcn = XCALLOC(MTYPE_BFDD_NOTIFICATION, sizeof(*pcn));
 864
 865         TAILQ_INSERT_HEAD(&pc->pc_pcnqueue, pcn, pcn_entry);
 866         pcn->pcn_pc = pc;
 867         pcn->pcn_bs = bs;
 868         bs->refcount++;
 869
 870         return pcn;
 871 }
 872
 873 static struct ptm_client_notification *pcn_lookup(struct ptm_client *pc,
 874                                                   struct bfd_session *bs)
 875 {
 876         struct ptm_client_notification *pcn;
 877
 878         TAILQ_FOREACH (pcn, &pc->pc_pcnqueue, pcn_entry) {
 879                 if (pcn->pcn_bs != bs)
 880                         continue;
 881
 882                 break;
 883         }
 884
 885         return pcn;
 886 }
 887
 888 static void pcn_free(struct ptm_client_notification *pcn)
 889 {
 890         struct ptm_client *pc;
 891         struct bfd_session *bs;
 892
 893         if (pcn == NULL)
 894                 return;
 895
 896         /* Handle session de-registration. */
 897         bs = pcn->pcn_bs;
 898         pcn->pcn_bs = NULL;
 899         bs->refcount--;
 900
 901         /* Handle ptm_client deregistration. */
 902         pc = pcn->pcn_pc;
 903         pcn->pcn_pc = NULL;
 904         TAILQ_REMOVE(&pc->pc_pcnqueue, pcn, pcn_entry);
 905
 906         XFREE(MTYPE_BFDD_NOTIFICATION, pcn);
 907 }