pimd/pim_zlookup.c

   1 /*
   2  * PIM for Quagga
   3  * Copyright (C) 2008  Everton da Silva Marques
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program 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 along
  16  * with this program; see the file COPYING; if not, write to the Free Software
  17  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
  18  */
  19
  20 #include <zebra.h>
  21
  22 #include "log.h"
  23 #include "prefix.h"
  24 #include "zclient.h"
  25 #include "stream.h"
  26 #include "network.h"
  27 #include "thread.h"
  28 #include "prefix.h"
  29 #include "vty.h"
  30 #include "lib_errors.h"
  31
  32 #include "pimd.h"
  33 #include "pim_instance.h"
  34 #include "pim_iface.h"
  35 #include "pim_neighbor.h"
  36 #include "pim_pim.h"
  37 #include "pim_str.h"
  38 #include "pim_oil.h"
  39 #include "pim_zlookup.h"
  40 #include "pim_addr.h"
  41
  42 static struct zclient *zlookup = NULL;
  43 struct thread *zlookup_read;
  44
  45 static void zclient_lookup_sched(struct zclient *zlookup, int delay);
  46 static void zclient_lookup_read_pipe(struct thread *thread);
  47
  48 /* Connect to zebra for nexthop lookup. */
  49 static void zclient_lookup_connect(struct thread *t)
  50 {
  51         struct zclient *zlookup;
  52
  53         zlookup = THREAD_ARG(t);
  54
  55         if (zlookup->sock >= 0) {
  56                 return;
  57         }
  58
  59         if (zclient_socket_connect(zlookup) < 0) {
  60                 ++zlookup->fail;
  61                 zlog_warn("%s: failure connecting zclient socket: failures=%d",
  62                           __func__, zlookup->fail);
  63         } else {
  64                 zlookup->fail = 0; /* reset counter on connection */
  65         }
  66
  67         if (zclient_send_hello(zlookup) == ZCLIENT_SEND_FAILURE) {
  68                 if (close(zlookup->sock)) {
  69                         zlog_warn("%s: closing fd=%d: errno=%d %s", __func__,
  70                                   zlookup->sock, errno, safe_strerror(errno));
  71                 }
  72                 zlookup->sock = -1;
  73         }
  74
  75         if (zlookup->sock < 0) {
  76                 /* Since last connect failed, retry within 10 secs */
  77                 zclient_lookup_sched(zlookup, 10);
  78                 return;
  79         }
  80
  81         thread_add_timer(router->master, zclient_lookup_read_pipe, zlookup, 60,
  82                          &zlookup_read);
  83 }
  84
  85 /* Schedule connection with delay. */
  86 static void zclient_lookup_sched(struct zclient *zlookup, int delay)
  87 {
  88         thread_add_timer(router->master, zclient_lookup_connect, zlookup, delay,
  89                          &zlookup->t_connect);
  90
  91         zlog_notice("%s: zclient lookup connection scheduled for %d seconds",
  92                     __func__, delay);
  93 }
  94
  95 /* Schedule connection for now. */
  96 static void zclient_lookup_sched_now(struct zclient *zlookup)
  97 {
  98         thread_add_event(router->master, zclient_lookup_connect, zlookup, 0,
  99                          &zlookup->t_connect);
 100
 101         zlog_notice("%s: zclient lookup immediate connection scheduled",
 102                     __func__);
 103 }
 104
 105 /* Schedule reconnection, if needed. */
 106 static void zclient_lookup_reconnect(struct zclient *zlookup)
 107 {
 108         if (zlookup->t_connect) {
 109                 return;
 110         }
 111
 112         zclient_lookup_sched_now(zlookup);
 113 }
 114
 115 static void zclient_lookup_failed(struct zclient *zlookup)
 116 {
 117         if (zlookup->sock >= 0) {
 118                 if (close(zlookup->sock)) {
 119                         zlog_warn("%s: closing fd=%d: errno=%d %s", __func__,
 120                                   zlookup->sock, errno, safe_strerror(errno));
 121                 }
 122                 zlookup->sock = -1;
 123         }
 124
 125         zclient_lookup_reconnect(zlookup);
 126 }
 127
 128 void zclient_lookup_free(void)
 129 {
 130         THREAD_OFF(zlookup_read);
 131         zclient_stop(zlookup);
 132         zclient_free(zlookup);
 133         zlookup = NULL;
 134 }
 135
 136 void zclient_lookup_new(void)
 137 {
 138         struct zclient_options options = zclient_options_default;
 139         options.synchronous = true;
 140
 141         zlookup = zclient_new(router->master, &options, NULL, 0);
 142         if (!zlookup) {
 143                 flog_err(EC_LIB_ZAPI_SOCKET, "%s: zclient_new() failure",
 144                          __func__);
 145                 return;
 146         }
 147
 148         zlookup->sock = -1;
 149         zlookup->t_connect = NULL;
 150         zlookup->privs = &pimd_privs;
 151
 152         zclient_lookup_sched_now(zlookup);
 153
 154         zlog_notice("%s: zclient lookup socket initialized", __func__);
 155 }
 156
 157 static int zclient_read_nexthop(struct pim_instance *pim,
 158                                 struct zclient *zlookup,
 159                                 struct pim_zlookup_nexthop nexthop_tab[],
 160                                 const int tab_size, pim_addr addr)
 161 {
 162         int num_ifindex = 0;
 163         struct stream *s;
 164         uint16_t length;
 165         uint8_t marker;
 166         uint8_t version;
 167         vrf_id_t vrf_id;
 168         uint16_t command = 0;
 169         struct ipaddr raddr;
 170         uint8_t distance;
 171         uint32_t metric;
 172         int nexthop_num;
 173         int i, err;
 174
 175         if (PIM_DEBUG_PIM_NHT_DETAIL)
 176                 zlog_debug("%s: addr=%pPAs(%s)", __func__, &addr,
 177                            pim->vrf->name);
 178
 179         s = zlookup->ibuf;
 180
 181         while (command != ZEBRA_NEXTHOP_LOOKUP_MRIB) {
 182                 stream_reset(s);
 183                 err = zclient_read_header(s, zlookup->sock, &length, &marker,
 184                                           &version, &vrf_id, &command);
 185                 if (err < 0) {
 186                         flog_err(EC_LIB_ZAPI_MISSMATCH,
 187                                  "%s: zclient_read_header() failed", __func__);
 188                         zclient_lookup_failed(zlookup);
 189                         return -1;
 190                 }
 191
 192                 if (command == ZEBRA_ERROR) {
 193                         enum zebra_error_types error;
 194
 195                         zapi_error_decode(s, &error);
 196                         /* Do nothing with it for now */
 197                         return -1;
 198                 }
 199         }
 200
 201         stream_get_ipaddr(s, &raddr);
 202
 203         if (raddr.ipa_type != PIM_IPADDR ||
 204             pim_addr_cmp(raddr.ipaddr_pim, addr)) {
 205                 zlog_warn("%s: address mismatch: addr=%pPA(%s) raddr=%pIA",
 206                           __func__, &addr, pim->vrf->name, &raddr);
 207                 /* warning only */
 208         }
 209
 210         distance = stream_getc(s);
 211         metric = stream_getl(s);
 212         nexthop_num = stream_getc(s);
 213
 214         if (nexthop_num < 1 || nexthop_num > router->multipath) {
 215                 if (PIM_DEBUG_PIM_NHT_DETAIL)
 216                         zlog_debug("%s: socket %d bad nexthop_num=%d", __func__,
 217                                    zlookup->sock, nexthop_num);
 218                 return -6;
 219         }
 220
 221         for (i = 0; i < nexthop_num; ++i) {
 222                 vrf_id_t nexthop_vrf_id;
 223                 enum nexthop_types_t nexthop_type;
 224                 struct in_addr nh_ip4;
 225                 struct in6_addr nh_ip6;
 226                 ifindex_t nh_ifi;
 227
 228                 nexthop_vrf_id = stream_getl(s);
 229                 nexthop_type = stream_getc(s);
 230                 if (num_ifindex >= tab_size) {
 231                         zlog_warn(
 232                                 "%s: found too many nexthop ifindexes (%d > %d) for address %pPAs(%s)",
 233                                 __func__, (num_ifindex + 1), tab_size, &addr,
 234                                 pim->vrf->name);
 235                         return num_ifindex;
 236                 }
 237                 nexthop_tab[num_ifindex].protocol_distance = distance;
 238                 nexthop_tab[num_ifindex].route_metric = metric;
 239                 nexthop_tab[num_ifindex].vrf_id = nexthop_vrf_id;
 240                 switch (nexthop_type) {
 241                 case NEXTHOP_TYPE_IFINDEX:
 242                         nexthop_tab[num_ifindex].ifindex = stream_getl(s);
 243                         /*
 244                          * Connected route (i.e. no nexthop), use
 245                          * address passed in as PIM nexthop.  This will
 246                          * allow us to work in cases where we are
 247                          * trying to find a route for this box.
 248                          */
 249                         nexthop_tab[num_ifindex].nexthop_addr = addr;
 250                         ++num_ifindex;
 251                         break;
 252                 case NEXTHOP_TYPE_IPV4_IFINDEX:
 253                 case NEXTHOP_TYPE_IPV4:
 254                         nh_ip4.s_addr = stream_get_ipv4(s);
 255                         nh_ifi = stream_getl(s);
 256 #if PIM_IPV == 4
 257                         nexthop_tab[num_ifindex].nexthop_addr = nh_ip4;
 258                         nexthop_tab[num_ifindex].ifindex = nh_ifi;
 259                         ++num_ifindex;
 260 #else
 261                         zlog_warn(
 262                                 "cannot use IPv4 nexthop %pI4(%d) for IPv6 %pPA",
 263                                 &nh_ip4, nh_ifi, &addr);
 264 #endif
 265                         break;
 266                 case NEXTHOP_TYPE_IPV6_IFINDEX:
 267                         stream_get(&nh_ip6, s, sizeof(nh_ip6));
 268                         nh_ifi = stream_getl(s);
 269
 270 #if PIM_IPV == 6
 271                         nexthop_tab[num_ifindex].nexthop_addr = nh_ip6;
 272                         nexthop_tab[num_ifindex].ifindex = nh_ifi;
 273                         ++num_ifindex;
 274 #else
 275                         /* RFC 5549 v4-over-v6 nexthop handling */
 276
 277                         /*
 278                          * If we are sending v6 secondary assume we receive v6
 279                          * secondary
 280                          */
 281                         struct interface *ifp = if_lookup_by_index(
 282                                 nh_ifi,
 283                                 nexthop_vrf_id);
 284
 285                         if (!ifp)
 286                                 break;
 287
 288                         struct pim_neighbor *nbr;
 289
 290                         if (pim->send_v6_secondary) {
 291                                 struct prefix p;
 292
 293                                 p.family = AF_INET6;
 294                                 p.prefixlen = IPV6_MAX_BITLEN;
 295                                 p.u.prefix6 = nh_ip6;
 296
 297                                 nbr = pim_neighbor_find_by_secondary(ifp, &p);
 298                         } else
 299                                 nbr = pim_neighbor_find_if(ifp);
 300
 301                         if (!nbr)
 302                                 break;
 303
 304                         nexthop_tab[num_ifindex].nexthop_addr =
 305                                 nbr->source_addr;
 306                         nexthop_tab[num_ifindex].ifindex = nh_ifi;
 307                         ++num_ifindex;
 308 #endif
 309                         break;
 310                 default:
 311                         /* do nothing */
 312                         zlog_warn(
 313                                 "%s: found non-ifindex nexthop type=%d for address %pPAs(%s)",
 314                                 __func__, nexthop_type, &addr, pim->vrf->name);
 315                         break;
 316                 }
 317         }
 318
 319         return num_ifindex;
 320 }
 321
 322 static int zclient_lookup_nexthop_once(struct pim_instance *pim,
 323                                        struct pim_zlookup_nexthop nexthop_tab[],
 324                                        const int tab_size, pim_addr addr)
 325 {
 326         struct stream *s;
 327         int ret;
 328         struct ipaddr ipaddr;
 329
 330         if (PIM_DEBUG_PIM_NHT_DETAIL)
 331                 zlog_debug("%s: addr=%pPAs(%s)", __func__, &addr,
 332                            pim->vrf->name);
 333
 334         /* Check socket. */
 335         if (zlookup->sock < 0) {
 336                 flog_err(EC_LIB_ZAPI_SOCKET,
 337                          "%s: zclient lookup socket is not connected",
 338                          __func__);
 339                 zclient_lookup_failed(zlookup);
 340                 return -1;
 341         }
 342
 343         if (pim->vrf->vrf_id == VRF_UNKNOWN) {
 344                 zlog_notice(
 345                         "%s: VRF: %s does not fully exist yet, delaying lookup",
 346                         __func__, pim->vrf->name);
 347                 return -1;
 348         }
 349
 350         ipaddr.ipa_type = PIM_IPADDR;
 351         ipaddr.ipaddr_pim = addr;
 352
 353         s = zlookup->obuf;
 354         stream_reset(s);
 355         zclient_create_header(s, ZEBRA_NEXTHOP_LOOKUP_MRIB, pim->vrf->vrf_id);
 356         stream_put_ipaddr(s, &ipaddr);
 357         stream_putw_at(s, 0, stream_get_endp(s));
 358
 359         ret = writen(zlookup->sock, s->data, stream_get_endp(s));
 360         if (ret < 0) {
 361                 flog_err(
 362                         EC_LIB_SOCKET,
 363                         "%s: writen() failure: %d writing to zclient lookup socket",
 364                         __func__, errno);
 365                 zclient_lookup_failed(zlookup);
 366                 return -2;
 367         }
 368         if (ret == 0) {
 369                 flog_err_sys(EC_LIB_SOCKET,
 370                              "%s: connection closed on zclient lookup socket",
 371                              __func__);
 372                 zclient_lookup_failed(zlookup);
 373                 return -3;
 374         }
 375
 376         return zclient_read_nexthop(pim, zlookup, nexthop_tab, tab_size, addr);
 377 }
 378
 379 void zclient_lookup_read_pipe(struct thread *thread)
 380 {
 381         struct zclient *zlookup = THREAD_ARG(thread);
 382         struct pim_instance *pim = pim_get_pim_instance(VRF_DEFAULT);
 383         struct pim_zlookup_nexthop nexthop_tab[10];
 384         pim_addr l = PIMADDR_ANY;
 385
 386         if (!pim) {
 387                 if (PIM_DEBUG_PIM_NHT_DETAIL)
 388                         zlog_debug("%s: Unable to find pim instance", __func__);
 389                 return;
 390         }
 391
 392         zclient_lookup_nexthop_once(pim, nexthop_tab, 10, l);
 393         thread_add_timer(router->master, zclient_lookup_read_pipe, zlookup, 60,
 394                          &zlookup_read);
 395 }
 396
 397 int zclient_lookup_nexthop(struct pim_instance *pim,
 398                            struct pim_zlookup_nexthop nexthop_tab[],
 399                            const int tab_size, pim_addr addr,
 400                            int max_lookup)
 401 {
 402         int lookup;
 403         uint32_t route_metric = 0xFFFFFFFF;
 404         uint8_t protocol_distance = 0xFF;
 405
 406         pim->nexthop_lookups++;
 407
 408         for (lookup = 0; lookup < max_lookup; ++lookup) {
 409                 int num_ifindex;
 410                 int first_ifindex;
 411                 pim_addr nexthop_addr;
 412
 413                 num_ifindex = zclient_lookup_nexthop_once(pim, nexthop_tab,
 414                                                           tab_size, addr);
 415                 if (num_ifindex < 1) {
 416                         if (PIM_DEBUG_PIM_NHT_DETAIL)
 417                                 zlog_debug(
 418                                         "%s: lookup=%d/%d: could not find nexthop ifindex for address %pPA(%s)",
 419                                         __func__, lookup, max_lookup, &addr,
 420                                         pim->vrf->name);
 421                         return -1;
 422                 }
 423
 424                 if (lookup < 1) {
 425                         /* this is the non-recursive lookup - save original
 426                          * metric/distance */
 427                         route_metric = nexthop_tab[0].route_metric;
 428                         protocol_distance = nexthop_tab[0].protocol_distance;
 429                 }
 430
 431                 /*
 432                  * FIXME: Non-recursive nexthop ensured only for first ifindex.
 433                  * However, recursive route lookup should really be fixed in
 434                  * zebra daemon.
 435                  * See also TODO T24.
 436                  *
 437                  * So Zebra for NEXTHOP_TYPE_IPV4 returns the ifindex now since
 438                  * it was being stored.  This Doesn't solve all cases of
 439                  * recursive lookup but for the most common types it does.
 440                  */
 441                 first_ifindex = nexthop_tab[0].ifindex;
 442                 nexthop_addr = nexthop_tab[0].nexthop_addr;
 443                 if (first_ifindex > 0) {
 444                         /* found: first ifindex is non-recursive nexthop */
 445
 446                         if (lookup > 0) {
 447                                 /* Report non-recursive success after first
 448                                  * lookup */
 449                                 if (PIM_DEBUG_PIM_NHT)
 450                                         zlog_debug(
 451                                                 "%s: lookup=%d/%d: found non-recursive ifindex=%d for address %pPA(%s) dist=%d met=%d",
 452                                                 __func__, lookup, max_lookup,
 453                                                 first_ifindex, &addr,
 454                                                 pim->vrf->name,
 455                                                 nexthop_tab[0]
 456                                                         .protocol_distance,
 457                                                 nexthop_tab[0].route_metric);
 458
 459                                 /* use last address as nexthop address */
 460                                 nexthop_tab[0].nexthop_addr = addr;
 461
 462                                 /* report original route metric/distance */
 463                                 nexthop_tab[0].route_metric = route_metric;
 464                                 nexthop_tab[0].protocol_distance =
 465                                         protocol_distance;
 466                         }
 467
 468                         return num_ifindex;
 469                 }
 470
 471                 if (PIM_DEBUG_PIM_NHT)
 472                         zlog_debug(
 473                                 "%s: lookup=%d/%d: zebra returned recursive nexthop %pPAs for address %pPA(%s) dist=%d met=%d",
 474                                 __func__, lookup, max_lookup, &nexthop_addr,
 475                                 &addr, pim->vrf->name,
 476                                 nexthop_tab[0].protocol_distance,
 477                                 nexthop_tab[0].route_metric);
 478
 479                 addr = nexthop_addr; /* use nexthop
 480                                         addr for recursive lookup */
 481
 482         } /* for (max_lookup) */
 483
 484         if (PIM_DEBUG_PIM_NHT)
 485                 zlog_warn(
 486                         "%s: lookup=%d/%d: failure searching recursive nexthop ifindex for address %pPA(%s)",
 487                         __func__, lookup, max_lookup, &addr, pim->vrf->name);
 488
 489         return -2;
 490 }
 491
 492 void pim_zlookup_show_ip_multicast(struct vty *vty)
 493 {
 494         vty_out(vty, "Zclient lookup socket: ");
 495         if (zlookup) {
 496                 vty_out(vty, "%d failures=%d\n", zlookup->sock, zlookup->fail);
 497         } else {
 498                 vty_out(vty, "<null zclient>\n");
 499         }
 500 }
 501
 502 int pim_zlookup_sg_statistics(struct channel_oil *c_oil)
 503 {
 504         struct stream *s = zlookup->obuf;
 505         uint16_t command = 0;
 506         unsigned long long lastused;
 507         pim_sgaddr sg;
 508         int count = 0;
 509         int ret;
 510         pim_sgaddr more = {};
 511         struct interface *ifp =
 512                 pim_if_find_by_vif_index(c_oil->pim, *oil_parent(c_oil));
 513
 514         if (PIM_DEBUG_ZEBRA) {
 515                 more.src = *oil_origin(c_oil);
 516                 more.grp = *oil_mcastgrp(c_oil);
 517                 zlog_debug(
 518                         "Sending Request for New Channel Oil Information%pSG VIIF %d(%s)",
 519                         &more, *oil_parent(c_oil), c_oil->pim->vrf->name);
 520         }
 521
 522         if (!ifp)
 523                 return -1;
 524
 525         stream_reset(s);
 526         zclient_create_header(s, ZEBRA_IPMR_ROUTE_STATS,
 527                               c_oil->pim->vrf->vrf_id);
 528         stream_putl(s, PIM_AF);
 529         stream_write(s, oil_origin(c_oil), sizeof(pim_addr));
 530         stream_write(s, oil_mcastgrp(c_oil), sizeof(pim_addr));
 531         stream_putl(s, ifp->ifindex);
 532         stream_putw_at(s, 0, stream_get_endp(s));
 533
 534         count = stream_get_endp(s);
 535         ret = writen(zlookup->sock, s->data, count);
 536         if (ret <= 0) {
 537                 flog_err(
 538                         EC_LIB_SOCKET,
 539                         "%s: writen() failure: %d writing to zclient lookup socket",
 540                         __func__, errno);
 541                 return -1;
 542         }
 543
 544         s = zlookup->ibuf;
 545
 546         while (command != ZEBRA_IPMR_ROUTE_STATS) {
 547                 int err;
 548                 uint16_t length = 0;
 549                 vrf_id_t vrf_id;
 550                 uint8_t marker;
 551                 uint8_t version;
 552
 553                 stream_reset(s);
 554                 err = zclient_read_header(s, zlookup->sock, &length, &marker,
 555                                           &version, &vrf_id, &command);
 556                 if (err < 0) {
 557                         flog_err(EC_LIB_ZAPI_MISSMATCH,
 558                                  "%s: zclient_read_header() failed", __func__);
 559                         zclient_lookup_failed(zlookup);
 560                         return -1;
 561                 }
 562         }
 563
 564         stream_get(&sg.src, s, sizeof(pim_addr));
 565         stream_get(&sg.grp, s, sizeof(pim_addr));
 566
 567         more.src = *oil_origin(c_oil);
 568         more.grp = *oil_mcastgrp(c_oil);
 569         if (pim_sgaddr_cmp(sg, more)) {
 570                 if (PIM_DEBUG_ZEBRA)
 571                         flog_err(
 572                                 EC_LIB_ZAPI_MISSMATCH,
 573                                 "%s: Received wrong %pSG(%s) information requested",
 574                                 __func__, &more, c_oil->pim->vrf->name);
 575                 zclient_lookup_failed(zlookup);
 576                 return -3;
 577         }
 578
 579         stream_get(&lastused, s, sizeof(lastused));
 580         /* signed success value from netlink_talk; currently unused */
 581         (void)stream_getl(s);
 582
 583         c_oil->cc.lastused = lastused;
 584
 585         return 0;
 586 }