zebra/zebra_rnh.c

   1 /* Zebra next hop tracking code
   2  * Copyright (C) 2013 Cumulus Networks, Inc.
   3  *
   4  * This file is part of GNU Zebra.
   5  *
   6  * GNU Zebra is free software; you can redistribute it and/or modify it
   7  * under the terms of the GNU General Public License as published by the
   8  * Free Software Foundation; either version 2, or (at your option) any
   9  * later version.
  10  *
  11  * GNU Zebra is distributed in the hope that it will be useful, but
  12  * WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License along
  17  * with this program; see the file COPYING; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
  19  */
  20
  21 #include <zebra.h>
  22
  23 #include "prefix.h"
  24 #include "table.h"
  25 #include "memory.h"
  26 #include "command.h"
  27 #include "if.h"
  28 #include "log.h"
  29 #include "sockunion.h"
  30 #include "linklist.h"
  31 #include "thread.h"
  32 #include "workqueue.h"
  33 #include "prefix.h"
  34 #include "routemap.h"
  35 #include "stream.h"
  36 #include "nexthop.h"
  37 #include "vrf.h"
  38
  39 #include "zebra/rib.h"
  40 #include "zebra/rt.h"
  41 #include "zebra/zserv.h"
  42 #include "zebra/zebra_ns.h"
  43 #include "zebra/zebra_vrf.h"
  44 #include "zebra/redistribute.h"
  45 #include "zebra/debug.h"
  46 #include "zebra/zebra_rnh.h"
  47 #include "zebra/zebra_routemap.h"
  48 #include "zebra/interface.h"
  49 #include "zebra/zebra_memory.h"
  50
  51 static void free_state(vrf_id_t vrf_id, struct route_entry *re,
  52                        struct route_node *rn);
  53 static void copy_state(struct rnh *rnh, struct route_entry *re,
  54                        struct route_node *rn);
  55 #define lookup_rnh_table(v, f)                                                 \
  56         ({                                                                     \
  57                 struct zebra_vrf *zvrf;                                        \
  58                 struct route_table *t = NULL;                                  \
  59                 zvrf = zebra_vrf_lookup_by_id(v);                              \
  60                 if (zvrf)                                                      \
  61                         t = zvrf->rnh_table[family2afi(f)];                    \
  62                 t;                                                             \
  63         })
  64
  65 static int compare_state(struct route_entry *r1, struct route_entry *r2);
  66 static int send_client(struct rnh *rnh, struct zserv *client, rnh_type_t type,
  67                        vrf_id_t vrf_id);
  68 static void print_rnh(struct route_node *rn, struct vty *vty);
  69
  70 int zebra_rnh_ip_default_route = 0;
  71 int zebra_rnh_ipv6_default_route = 0;
  72
  73 static inline struct route_table *get_rnh_table(vrf_id_t vrfid, int family,
  74                                                 rnh_type_t type)
  75 {
  76         struct zebra_vrf *zvrf;
  77         struct route_table *t = NULL;
  78
  79         zvrf = zebra_vrf_lookup_by_id(vrfid);
  80         if (zvrf)
  81                 switch (type) {
  82                 case RNH_NEXTHOP_TYPE:
  83                         t = zvrf->rnh_table[family2afi(family)];
  84                         break;
  85                 case RNH_IMPORT_CHECK_TYPE:
  86                         t = zvrf->import_check_table[family2afi(family)];
  87                         break;
  88                 }
  89
  90         return t;
  91 }
  92
  93 char *rnh_str(struct rnh *rnh, char *buf, int size)
  94 {
  95         prefix2str(&(rnh->node->p), buf, size);
  96         return buf;
  97 }
  98
  99 struct rnh *zebra_add_rnh(struct prefix *p, vrf_id_t vrfid, rnh_type_t type)
 100 {
 101         struct route_table *table;
 102         struct route_node *rn;
 103         struct rnh *rnh = NULL;
 104         char buf[PREFIX2STR_BUFFER];
 105
 106         if (IS_ZEBRA_DEBUG_NHT) {
 107                 prefix2str(p, buf, sizeof(buf));
 108                 zlog_debug("%u: Add RNH %s type %d", vrfid, buf, type);
 109         }
 110         table = get_rnh_table(vrfid, PREFIX_FAMILY(p), type);
 111         if (!table) {
 112                 prefix2str(p, buf, sizeof(buf));
 113                 zlog_warn("%u: Add RNH %s type %d - table not found", vrfid,
 114                           buf, type);
 115                 return NULL;
 116         }
 117
 118         /* Make it sure prefixlen is applied to the prefix. */
 119         apply_mask(p);
 120
 121         /* Lookup (or add) route node.*/
 122         rn = route_node_get(table, p);
 123
 124         if (!rn->info) {
 125                 rnh = XCALLOC(MTYPE_RNH, sizeof(struct rnh));
 126                 rnh->client_list = list_new();
 127                 rnh->vrf_id = vrfid;
 128                 rnh->zebra_static_route_list = list_new();
 129                 rnh->zebra_pseudowire_list = list_new();
 130                 route_lock_node(rn);
 131                 rn->info = rnh;
 132                 rnh->node = rn;
 133         }
 134
 135         route_unlock_node(rn);
 136         return (rn->info);
 137 }
 138
 139 struct rnh *zebra_lookup_rnh(struct prefix *p, vrf_id_t vrfid, rnh_type_t type)
 140 {
 141         struct route_table *table;
 142         struct route_node *rn;
 143
 144         table = get_rnh_table(vrfid, PREFIX_FAMILY(p), type);
 145         if (!table)
 146                 return NULL;
 147
 148         /* Make it sure prefixlen is applied to the prefix. */
 149         apply_mask(p);
 150
 151         /* Lookup route node.*/
 152         rn = route_node_lookup(table, p);
 153         if (!rn)
 154                 return NULL;
 155
 156         route_unlock_node(rn);
 157         return (rn->info);
 158 }
 159
 160 void zebra_free_rnh(struct rnh *rnh)
 161 {
 162         rnh->flags |= ZEBRA_NHT_DELETED;
 163         list_delete_and_null(&rnh->client_list);
 164         list_delete_and_null(&rnh->zebra_static_route_list);
 165         list_delete_and_null(&rnh->zebra_pseudowire_list);
 166         free_state(rnh->vrf_id, rnh->state, rnh->node);
 167         XFREE(MTYPE_RNH, rnh);
 168 }
 169
 170 void zebra_delete_rnh(struct rnh *rnh, rnh_type_t type)
 171 {
 172         struct route_node *rn;
 173
 174         if (!rnh || (rnh->flags & ZEBRA_NHT_DELETED) || !(rn = rnh->node))
 175                 return;
 176
 177         if (IS_ZEBRA_DEBUG_NHT) {
 178                 char buf[PREFIX2STR_BUFFER];
 179                 zlog_debug("%u: Del RNH %s type %d", rnh->vrf_id,
 180                            rnh_str(rnh, buf, sizeof(buf)), type);
 181         }
 182
 183         zebra_free_rnh(rnh);
 184         rn->info = NULL;
 185         route_unlock_node(rn);
 186 }
 187
 188 void zebra_add_rnh_client(struct rnh *rnh, struct zserv *client,
 189                           rnh_type_t type, vrf_id_t vrf_id)
 190 {
 191         if (IS_ZEBRA_DEBUG_NHT) {
 192                 char buf[PREFIX2STR_BUFFER];
 193                 zlog_debug("%u: Client %s registers for RNH %s type %d", vrf_id,
 194                            zebra_route_string(client->proto),
 195                            rnh_str(rnh, buf, sizeof(buf)), type);
 196         }
 197         if (!listnode_lookup(rnh->client_list, client)) {
 198                 listnode_add(rnh->client_list, client);
 199                 send_client(rnh, client, type,
 200                             vrf_id); // Pending: check if its needed
 201         }
 202 }
 203
 204 void zebra_remove_rnh_client(struct rnh *rnh, struct zserv *client,
 205                              rnh_type_t type)
 206 {
 207         if (IS_ZEBRA_DEBUG_NHT) {
 208                 char buf[PREFIX2STR_BUFFER];
 209                 zlog_debug("Client %s unregisters for RNH %s type %d",
 210                            zebra_route_string(client->proto),
 211                            rnh_str(rnh, buf, sizeof(buf)), type);
 212         }
 213         listnode_delete(rnh->client_list, client);
 214         if (list_isempty(rnh->client_list)
 215             && list_isempty(rnh->zebra_static_route_list)
 216             && list_isempty(rnh->zebra_pseudowire_list))
 217                 zebra_delete_rnh(rnh, type);
 218 }
 219
 220 void zebra_register_rnh_static_nh(vrf_id_t vrf_id, struct prefix *nh,
 221                                   struct route_node *static_rn)
 222 {
 223         struct rnh *rnh;
 224
 225         rnh = zebra_add_rnh(nh, vrf_id, RNH_NEXTHOP_TYPE);
 226         if (rnh && !listnode_lookup(rnh->zebra_static_route_list, static_rn)) {
 227                 listnode_add(rnh->zebra_static_route_list, static_rn);
 228         }
 229 }
 230
 231 void zebra_deregister_rnh_static_nh(vrf_id_t vrf_id, struct prefix *nh,
 232                                     struct route_node *static_rn)
 233 {
 234         struct rnh *rnh;
 235
 236         rnh = zebra_lookup_rnh(nh, vrf_id, RNH_NEXTHOP_TYPE);
 237         if (!rnh || (rnh->flags & ZEBRA_NHT_DELETED))
 238                 return;
 239
 240         listnode_delete(rnh->zebra_static_route_list, static_rn);
 241
 242         if (list_isempty(rnh->client_list)
 243             && list_isempty(rnh->zebra_static_route_list)
 244             && list_isempty(rnh->zebra_pseudowire_list))
 245                 zebra_delete_rnh(rnh, RNH_NEXTHOP_TYPE);
 246 }
 247
 248 void zebra_deregister_rnh_static_nexthops(vrf_id_t vrf_id,
 249                                           struct nexthop *nexthop,
 250                                           struct route_node *rn)
 251 {
 252         struct nexthop *nh;
 253         struct prefix nh_p;
 254
 255         for (nh = nexthop; nh; nh = nh->next) {
 256                 switch (nh->type) {
 257                 case NEXTHOP_TYPE_IPV4:
 258                 case NEXTHOP_TYPE_IPV4_IFINDEX:
 259                         nh_p.family = AF_INET;
 260                         nh_p.prefixlen = IPV4_MAX_BITLEN;
 261                         nh_p.u.prefix4 = nh->gate.ipv4;
 262                         break;
 263                 case NEXTHOP_TYPE_IPV6:
 264                 case NEXTHOP_TYPE_IPV6_IFINDEX:
 265                         nh_p.family = AF_INET6;
 266                         nh_p.prefixlen = IPV6_MAX_BITLEN;
 267                         nh_p.u.prefix6 = nh->gate.ipv6;
 268                         break;
 269                 /*
 270                  * Not sure what really to do here, we are not
 271                  * supposed to have either of these for NHT
 272                  * and the code has no way to know what prefix
 273                  * to use.  So I'm going to just continue
 274                  * for the moment, which is preferable to
 275                  * what is currently happening which is a
 276                  * CRASH and BURN.
 277                  * Some simple testing shows that we
 278                  * are not leaving slag around for these
 279                  * skipped static routes.  Since
 280                  * they don't appear to be installed
 281                  */
 282                 case NEXTHOP_TYPE_IFINDEX:
 283                 case NEXTHOP_TYPE_BLACKHOLE:
 284                         continue;
 285                         break;
 286                 }
 287                 zebra_deregister_rnh_static_nh(vrf_id, &nh_p, rn);
 288         }
 289 }
 290
 291 /* XXX move this utility function elsewhere? */
 292 static void addr2hostprefix(int af, const union g_addr *addr,
 293                             struct prefix *prefix)
 294 {
 295         switch (af) {
 296         case AF_INET:
 297                 prefix->family = AF_INET;
 298                 prefix->prefixlen = IPV4_MAX_BITLEN;
 299                 prefix->u.prefix4 = addr->ipv4;
 300                 break;
 301         case AF_INET6:
 302                 prefix->family = AF_INET6;
 303                 prefix->prefixlen = IPV6_MAX_BITLEN;
 304                 prefix->u.prefix6 = addr->ipv6;
 305                 break;
 306         default:
 307                 memset(prefix, 0, sizeof(*prefix));
 308                 zlog_warn("%s: unknown address family %d", __func__, af);
 309                 break;
 310         }
 311 }
 312
 313 void zebra_register_rnh_pseudowire(vrf_id_t vrf_id, struct zebra_pw *pw)
 314 {
 315         struct prefix nh;
 316         struct rnh *rnh;
 317
 318         addr2hostprefix(pw->af, &pw->nexthop, &nh);
 319         rnh = zebra_add_rnh(&nh, vrf_id, RNH_NEXTHOP_TYPE);
 320         if (rnh && !listnode_lookup(rnh->zebra_pseudowire_list, pw)) {
 321                 listnode_add(rnh->zebra_pseudowire_list, pw);
 322                 pw->rnh = rnh;
 323                 zebra_evaluate_rnh(vrf_id, pw->af, 1, RNH_NEXTHOP_TYPE, &nh);
 324         }
 325 }
 326
 327 void zebra_deregister_rnh_pseudowire(vrf_id_t vrf_id, struct zebra_pw *pw)
 328 {
 329         struct rnh *rnh;
 330
 331         rnh = pw->rnh;
 332         if (!rnh)
 333                 return;
 334
 335         listnode_delete(rnh->zebra_pseudowire_list, pw);
 336         pw->rnh = NULL;
 337
 338         if (list_isempty(rnh->client_list)
 339             && list_isempty(rnh->zebra_static_route_list)
 340             && list_isempty(rnh->zebra_pseudowire_list))
 341                 zebra_delete_rnh(rnh, RNH_NEXTHOP_TYPE);
 342 }
 343
 344 /* Apply the NHT route-map for a client to the route (and nexthops)
 345  * resolving a NH.
 346  */
 347 static int zebra_rnh_apply_nht_rmap(int family, struct route_node *prn,
 348                                     struct route_entry *re, int proto)
 349 {
 350         int at_least_one = 0;
 351         int rmap_family; /* Route map has diff AF family enum */
 352         struct nexthop *nexthop;
 353         int ret;
 354
 355         rmap_family = (family == AF_INET) ? AFI_IP : AFI_IP6;
 356
 357         if (prn && re) {
 358                 for (nexthop = re->nexthop; nexthop; nexthop = nexthop->next) {
 359                         ret = zebra_nht_route_map_check(rmap_family, proto,
 360                                                         &prn->p, re, nexthop);
 361                         if (ret != RMAP_DENYMATCH) {
 362                                 SET_FLAG(nexthop->flags, NEXTHOP_FLAG_ACTIVE);
 363                                 at_least_one++; /* at least one valid NH */
 364                         } else {
 365                                 UNSET_FLAG(nexthop->flags, NEXTHOP_FLAG_ACTIVE);
 366                         }
 367                 }
 368         }
 369         return (at_least_one);
 370 }
 371
 372 /*
 373  * Determine appropriate route (RE entry) resolving a tracked BGP route
 374  * for BGP route for import.
 375  */
 376 static
 377 struct route_entry *zebra_rnh_resolve_import_entry(vrf_id_t vrfid,
 378                                                    int family,
 379                                                    struct route_node *nrn,
 380                                                    struct rnh *rnh,
 381                                                    struct route_node **prn)
 382 {
 383         struct route_table *route_table;
 384         struct route_node *rn;
 385         struct route_entry *re;
 386
 387         *prn = NULL;
 388
 389         route_table = zebra_vrf_table(family2afi(family), SAFI_UNICAST, vrfid);
 390         if (!route_table) // unexpected
 391                 return NULL;
 392
 393         rn = route_node_match(route_table, &nrn->p);
 394         if (!rn)
 395                 return NULL;
 396
 397         /* Unlock route node - we don't need to lock when walking the tree. */
 398         route_unlock_node(rn);
 399
 400         if (CHECK_FLAG(rnh->flags, ZEBRA_NHT_EXACT_MATCH) &&
 401              !prefix_same(&nrn->p, &rn->p))
 402                 return NULL;
 403
 404         /* Identify appropriate route entry. */
 405         RNODE_FOREACH_RE(rn, re) {
 406                 if (!CHECK_FLAG(re->status, ROUTE_ENTRY_REMOVED) &&
 407                     CHECK_FLAG(re->flags, ZEBRA_FLAG_SELECTED) &&
 408                     (re->type != ZEBRA_ROUTE_BGP))
 409                         break;
 410         }
 411
 412         if (re)
 413                 *prn = rn;
 414         return re;
 415 }
 416
 417 /*
 418  * See if a tracked route entry for import (by BGP) has undergone any
 419  * change, and if so, notify the client.
 420  */
 421 static void zebra_rnh_eval_import_check_entry(vrf_id_t vrfid, int family,
 422                                               int force, struct route_node *nrn,
 423                                               struct rnh *rnh,
 424                                               struct route_entry *re)
 425 {
 426         int state_changed = 0;
 427         struct zserv *client;
 428         char bufn[INET6_ADDRSTRLEN];
 429         struct listnode *node;
 430         struct nexthop *nexthop;
 431
 432         if (re && (rnh->state == NULL)) {
 433                 for (ALL_NEXTHOPS(re->nexthop, nexthop))
 434                         if (CHECK_FLAG(nexthop->flags, NEXTHOP_FLAG_FIB)) {
 435                                 state_changed = 1;
 436                                 break;
 437                         }
 438         } else if (!re && (rnh->state != NULL))
 439                 state_changed = 1;
 440
 441         if (compare_state(re, rnh->state))
 442                 copy_state(rnh, re, nrn);
 443
 444         if (state_changed || force) {
 445                 if (IS_ZEBRA_DEBUG_NHT) {
 446                         prefix2str(&nrn->p, bufn, INET6_ADDRSTRLEN);
 447                         zlog_debug("%u:%s: Route import check %s %s\n", vrfid,
 448                                    bufn, rnh->state ? "passed" : "failed",
 449                                    state_changed ? "(state changed)" : "");
 450                 }
 451                 /* state changed, notify clients */
 452                 for (ALL_LIST_ELEMENTS_RO(rnh->client_list, node, client)) {
 453                         send_client(rnh, client, RNH_IMPORT_CHECK_TYPE, vrfid);
 454                 }
 455         }
 456 }
 457
 458 /*
 459  * Notify clients registered for this nexthop about a change.
 460  */
 461 static void zebra_rnh_notify_protocol_clients(vrf_id_t vrfid, int family,
 462                                               struct route_node *nrn,
 463                                               struct rnh *rnh,
 464                                               struct route_node *prn,
 465                                               struct route_entry *re)
 466 {
 467         struct listnode *node;
 468         struct zserv *client;
 469         char bufn[INET6_ADDRSTRLEN];
 470         char bufp[INET6_ADDRSTRLEN];
 471         int num_resolving_nh;
 472
 473         if (IS_ZEBRA_DEBUG_NHT) {
 474                 prefix2str(&nrn->p, bufn, INET6_ADDRSTRLEN);
 475                 if (prn && re) {
 476                         prefix2str(&prn->p, bufp, INET6_ADDRSTRLEN);
 477                         zlog_debug("%u:%s: NH resolved over route %s", vrfid,
 478                                    bufn, bufp);
 479                 } else
 480                         zlog_debug("%u:%s: NH has become unresolved", vrfid,
 481                                    bufn);
 482         }
 483
 484         for (ALL_LIST_ELEMENTS_RO(rnh->client_list, node, client)) {
 485                 if (prn && re) {
 486                         /* Apply route-map for this client to route resolving
 487                          * this
 488                          * nexthop to see if it is filtered or not.
 489                          */
 490                         num_resolving_nh = zebra_rnh_apply_nht_rmap(
 491                                 family, prn, re, client->proto);
 492                         if (num_resolving_nh)
 493                                 rnh->filtered[client->proto] = 0;
 494                         else
 495                                 rnh->filtered[client->proto] = 1;
 496
 497                         if (IS_ZEBRA_DEBUG_NHT)
 498                                 zlog_debug(
 499                                         "%u:%s: Notifying client %s about NH %s",
 500                                         vrfid, bufn,
 501                                         zebra_route_string(client->proto),
 502                                         num_resolving_nh
 503                                                 ? ""
 504                                                 : "(filtered by route-map)");
 505                 } else {
 506                         rnh->filtered[client->proto] = 0;
 507                         if (IS_ZEBRA_DEBUG_NHT)
 508                                 zlog_debug(
 509                                         "%u:%s: Notifying client %s about NH (unreachable)",
 510                                         vrfid, bufn,
 511                                         zebra_route_string(client->proto));
 512                 }
 513
 514                 send_client(rnh, client, RNH_NEXTHOP_TYPE, vrfid);
 515         }
 516 }
 517
 518 static void zebra_rnh_process_static_routes(vrf_id_t vrfid, int family,
 519                                             struct route_node *nrn,
 520                                             struct rnh *rnh,
 521                                             struct route_node *prn,
 522                                             struct route_entry *re)
 523 {
 524         struct listnode *node;
 525         int num_resolving_nh = 0;
 526         struct route_node *static_rn;
 527         struct route_entry *sre;
 528         struct nexthop *nexthop;
 529         char bufn[INET6_ADDRSTRLEN];
 530         char bufp[INET6_ADDRSTRLEN];
 531         char bufs[INET6_ADDRSTRLEN];
 532
 533         if (IS_ZEBRA_DEBUG_NHT) {
 534                 prefix2str(&nrn->p, bufn, INET6_ADDRSTRLEN);
 535                 if (prn)
 536                         prefix2str(&prn->p, bufp, INET6_ADDRSTRLEN);
 537         }
 538
 539         if (prn && re) {
 540                 /* Apply route-map for "static" to route resolving this
 541                  * nexthop to see if it is filtered or not.
 542                  */
 543                 num_resolving_nh = zebra_rnh_apply_nht_rmap(family, prn, re,
 544                                                             ZEBRA_ROUTE_STATIC);
 545                 if (num_resolving_nh)
 546                         rnh->filtered[ZEBRA_ROUTE_STATIC] = 0;
 547                 else
 548                         rnh->filtered[ZEBRA_ROUTE_STATIC] = 1;
 549         } else
 550                 rnh->filtered[ZEBRA_ROUTE_STATIC] = 0;
 551
 552         /* Evaluate each static route associated with this nexthop. */
 553         for (ALL_LIST_ELEMENTS_RO(rnh->zebra_static_route_list, node,
 554                                   static_rn)) {
 555                 RNODE_FOREACH_RE (static_rn, sre) {
 556                         if (sre->type != ZEBRA_ROUTE_STATIC)
 557                                 continue;
 558
 559                         /* Set the filter flag for the correct nexthop - static
 560                          * route may
 561                          * be having multiple. We care here only about
 562                          * registered nexthops.
 563                          */
 564                         for (nexthop = sre->nexthop; nexthop;
 565                              nexthop = nexthop->next) {
 566                                 switch (nexthop->type) {
 567                                 case NEXTHOP_TYPE_IPV4:
 568                                 case NEXTHOP_TYPE_IPV4_IFINDEX:
 569                                         if (nexthop->gate.ipv4.s_addr
 570                                             == nrn->p.u.prefix4.s_addr) {
 571                                                 if (num_resolving_nh)
 572                                                         UNSET_FLAG(
 573                                                                 nexthop->flags,
 574                                                                 NEXTHOP_FLAG_FILTERED);
 575                                                 else
 576                                                         SET_FLAG(
 577                                                                 nexthop->flags,
 578                                                                 NEXTHOP_FLAG_FILTERED);
 579                                         }
 580                                         break;
 581                                 case NEXTHOP_TYPE_IPV6:
 582                                 case NEXTHOP_TYPE_IPV6_IFINDEX:
 583
 584                                         if (memcmp(&nexthop->gate.ipv6,
 585                                                    &nrn->p.u.prefix6, 16)
 586                                             == 0) {
 587                                                 if (num_resolving_nh)
 588                                                         UNSET_FLAG(
 589                                                                 nexthop->flags,
 590                                                                 NEXTHOP_FLAG_FILTERED);
 591                                                 else
 592                                                         SET_FLAG(
 593                                                                 nexthop->flags,
 594                                                                 NEXTHOP_FLAG_FILTERED);
 595                                         }
 596                                         break;
 597                                 default:
 598                                         break;
 599                                 }
 600                         }
 601
 602                         if (IS_ZEBRA_DEBUG_NHT) {
 603                                 prefix2str(&static_rn->p, bufs,
 604                                            INET6_ADDRSTRLEN);
 605                                 if (prn && re)
 606                                         zlog_debug(
 607                                                 "%u:%s: NH change %s, scheduling static route %s",
 608                                                 vrfid, bufn,
 609                                                 num_resolving_nh
 610                                                         ? ""
 611                                                         : "(filtered by route-map)",
 612                                                 bufs);
 613                                 else
 614                                         zlog_debug(
 615                                                 "%u:%s: NH unreachable, scheduling static route %s",
 616                                                 vrfid, bufn, bufs);
 617                         }
 618
 619                         SET_FLAG(sre->status, ROUTE_ENTRY_CHANGED);
 620                         SET_FLAG(sre->status, ROUTE_ENTRY_NEXTHOPS_CHANGED);
 621                 }
 622
 623                 rib_queue_add(static_rn);
 624         }
 625 }
 626
 627 /*
 628  * Determine appropriate route (route entry) resolving a tracked
 629  * nexthop.
 630  */
 631 static struct route_entry *zebra_rnh_resolve_nexthop_entry(vrf_id_t vrfid,
 632                                                      int family,
 633                                                      struct route_node *nrn,
 634                                                      struct rnh *rnh,
 635                                                      struct route_node **prn)
 636 {
 637         struct route_table *route_table;
 638         struct route_node *rn;
 639         struct route_entry *re;
 640
 641         *prn = NULL;
 642
 643         route_table = zebra_vrf_table(family2afi(family), SAFI_UNICAST, vrfid);
 644         if (!route_table)
 645                 return NULL;
 646
 647         rn = route_node_match(route_table, &nrn->p);
 648         if (!rn)
 649                 return NULL;
 650
 651         /* Unlock route node - we don't need to lock when walking the tree. */
 652         route_unlock_node(rn);
 653
 654         /* While resolving nexthops, we may need to walk up the tree from the
 655          * most-specific match. Do similar logic as in zebra_rib.c
 656          */
 657         while (rn) {
 658                 /* Do not resolve over default route unless allowed &&
 659                  * match route to be exact if so specified
 660                  */
 661                 if (is_default_prefix(&rn->p) &&
 662                     !nh_resolve_via_default(rn->p.family))
 663                         return NULL;
 664
 665                 /* Identify appropriate route entry. */
 666                 RNODE_FOREACH_RE(rn, re) {
 667                         if (CHECK_FLAG(re->status, ROUTE_ENTRY_REMOVED))
 668                                 continue;
 669                         if (!CHECK_FLAG(re->flags, ZEBRA_FLAG_SELECTED))
 670                                 continue;
 671
 672                         if (CHECK_FLAG(rnh->flags, ZEBRA_NHT_CONNECTED)) {
 673                                 if ((re->type == ZEBRA_ROUTE_CONNECT)
 674                                     || (re->type == ZEBRA_ROUTE_STATIC))
 675                                         break;
 676                                 if (re->type == ZEBRA_ROUTE_NHRP) {
 677                                         struct nexthop *nexthop;
 678
 679                                         for (nexthop = re->nexthop;
 680                                              nexthop;
 681                                              nexthop = nexthop->next)
 682                                                 if (nexthop->type
 683                                                      == NEXTHOP_TYPE_IFINDEX)
 684                                                         break;
 685                                         if (nexthop)
 686                                                 break;
 687                                 }
 688                         } else
 689                                 break;
 690                 }
 691
 692                 /* Route entry found, we're done; else, walk up the tree. */
 693                 if (re) {
 694                         *prn = rn;
 695                         return re;
 696                 }
 697
 698                 if (CHECK_FLAG(rnh->flags, ZEBRA_NHT_CONNECTED))
 699                         rn = rn->parent;
 700                 else
 701                         return NULL;
 702         }
 703
 704         return NULL;
 705 }
 706
 707 static void zebra_rnh_process_pseudowires(vrf_id_t vrfid, struct rnh *rnh)
 708 {
 709         struct zebra_pw *pw;
 710         struct listnode *node;
 711
 712         for (ALL_LIST_ELEMENTS_RO(rnh->zebra_pseudowire_list, node, pw))
 713                 zebra_pw_update(pw);
 714 }
 715
 716 /*
 717  * See if a tracked nexthop entry has undergone any change, and if so,
 718  * take appropriate action; this involves notifying any clients and/or
 719  * scheduling dependent static routes for processing.
 720  */
 721 static void zebra_rnh_eval_nexthop_entry(vrf_id_t vrfid, int family, int force,
 722                                          struct route_node *nrn,
 723                                          struct rnh *rnh,
 724                                          struct route_node *prn,
 725                                          struct route_entry *re)
 726 {
 727         int state_changed = 0;
 728
 729         /* If we're resolving over a different route, resolution has changed or
 730          * the resolving route has some change (e.g., metric), there is a state
 731          * change.
 732          */
 733         if (!prefix_same(&rnh->resolved_route, &prn->p)) {
 734                 if (prn)
 735                         prefix_copy(&rnh->resolved_route, &prn->p);
 736                 else
 737                         memset(&rnh->resolved_route, 0, sizeof(struct prefix));
 738
 739                 copy_state(rnh, re, nrn);
 740                 state_changed = 1;
 741         } else if (compare_state(re, rnh->state)) {
 742                 copy_state(rnh, re, nrn);
 743                 state_changed = 1;
 744         }
 745
 746         if (state_changed || force) {
 747                 /* NOTE: Use the "copy" of resolving route stored in 'rnh' i.e.,
 748                  * rnh->state.
 749                  */
 750                 /* Notify registered protocol clients. */
 751                 zebra_rnh_notify_protocol_clients(vrfid, family, nrn, rnh, prn,
 752                                                   rnh->state);
 753
 754                 /* Process static routes attached to this nexthop */
 755                 zebra_rnh_process_static_routes(vrfid, family, nrn, rnh, prn,
 756                                                 rnh->state);
 757
 758                 /* Process pseudowires attached to this nexthop */
 759                 zebra_rnh_process_pseudowires(vrfid, rnh);
 760         }
 761 }
 762
 763 /* Evaluate one tracked entry */
 764 static void zebra_rnh_evaluate_entry(vrf_id_t vrfid, int family, int force,
 765                                      rnh_type_t type, struct route_node *nrn)
 766 {
 767         struct rnh *rnh;
 768         struct route_entry *re;
 769         struct route_node *prn;
 770         char bufn[INET6_ADDRSTRLEN];
 771
 772         if (IS_ZEBRA_DEBUG_NHT) {
 773                 prefix2str(&nrn->p, bufn, INET6_ADDRSTRLEN);
 774                 zlog_debug("%u:%s: Evaluate RNH, type %d %s", vrfid, bufn, type,
 775                            force ? "(force)" : "");
 776         }
 777
 778         rnh = nrn->info;
 779
 780         /* Identify route entry (RE) resolving this tracked entry. */
 781         if (type == RNH_IMPORT_CHECK_TYPE)
 782                 re = zebra_rnh_resolve_import_entry(vrfid, family, nrn,
 783                                                     rnh, &prn);
 784         else
 785                 re = zebra_rnh_resolve_nexthop_entry(vrfid, family, nrn, rnh,
 786                                                      &prn);
 787
 788         /* If the entry cannot be resolved and that is also the existing state,
 789          * there is nothing further to do.
 790          */
 791         if (!re && rnh->state == NULL && !force)
 792                 return;
 793
 794         /* Process based on type of entry. */
 795         if (type == RNH_IMPORT_CHECK_TYPE)
 796                 zebra_rnh_eval_import_check_entry(vrfid, family, force, nrn,
 797                                                   rnh, re);
 798         else
 799                 zebra_rnh_eval_nexthop_entry(vrfid, family, force, nrn, rnh,
 800                                              prn, re);
 801 }
 802
 803 /*
 804  * Clear the ROUTE_ENTRY_NEXTHOPS_CHANGED flag
 805  * from the re entries.
 806  *
 807  * Please note we are doing this *after* we have
 808  * notified the world about each nexthop as that
 809  * we can have a situation where one re entry
 810  * covers multiple nexthops we are interested in.
 811  */
 812 static void zebra_rnh_clear_nhc_flag(vrf_id_t vrfid, int family,
 813                                      rnh_type_t type, struct route_node *nrn)
 814 {
 815         struct rnh *rnh;
 816         struct route_entry *re;
 817         struct route_node *prn;
 818
 819         rnh = nrn->info;
 820
 821         /* Identify route entry (RIB) resolving this tracked entry. */
 822         if (type == RNH_IMPORT_CHECK_TYPE)
 823                 re = zebra_rnh_resolve_import_entry(vrfid, family, nrn,
 824                                                     rnh, &prn);
 825         else
 826                 re = zebra_rnh_resolve_nexthop_entry(vrfid, family, nrn, rnh,
 827                                                      &prn);
 828
 829         if (re) {
 830                 UNSET_FLAG(re->status, ROUTE_ENTRY_NEXTHOPS_CHANGED);
 831                 UNSET_FLAG(re->status, ROUTE_ENTRY_LABELS_CHANGED);
 832         }
 833 }
 834
 835 /* Evaluate all tracked entries (nexthops or routes for import into BGP)
 836  * of a particular VRF and address-family or a specific prefix.
 837  */
 838 void zebra_evaluate_rnh(vrf_id_t vrfid, int family, int force, rnh_type_t type,
 839                         struct prefix *p)
 840 {
 841         struct route_table *rnh_table;
 842         struct route_node *nrn;
 843
 844         rnh_table = get_rnh_table(vrfid, family, type);
 845         if (!rnh_table) // unexpected
 846                 return;
 847
 848         if (p) {
 849                 /* Evaluating a specific entry, make sure it exists. */
 850                 nrn = route_node_lookup(rnh_table, p);
 851                 if (nrn && nrn->info)
 852                         zebra_rnh_evaluate_entry(vrfid, family, force, type,
 853                                                  nrn);
 854
 855                 if (nrn)
 856                         route_unlock_node(nrn);
 857         } else {
 858                 /* Evaluate entire table. */
 859                 nrn = route_top(rnh_table);
 860                 while (nrn) {
 861                         if (nrn->info)
 862                                 zebra_rnh_evaluate_entry(vrfid, family, force,
 863                                                          type, nrn);
 864                         nrn = route_next(nrn); /* this will also unlock nrn */
 865                 }
 866                 nrn = route_top(rnh_table);
 867                 while (nrn) {
 868                         if (nrn->info)
 869                                 zebra_rnh_clear_nhc_flag(vrfid, family, type,
 870                                                          nrn);
 871                         nrn = route_next(nrn); /* this will also unlock nrn */
 872                 }
 873         }
 874 }
 875
 876 void zebra_print_rnh_table(vrf_id_t vrfid, int af, struct vty *vty,
 877                            rnh_type_t type)
 878 {
 879         struct route_table *table;
 880         struct route_node *rn;
 881
 882         table = get_rnh_table(vrfid, af, type);
 883         if (!table) {
 884                 zlog_debug("print_rnhs: rnh table not found\n");
 885                 return;
 886         }
 887
 888         for (rn = route_top(table); rn; rn = route_next(rn))
 889                 if (rn->info)
 890                         print_rnh(rn, vty);
 891 }
 892
 893 int zebra_cleanup_rnh_client(vrf_id_t vrf_id, int family, struct zserv *client,
 894                              rnh_type_t type)
 895 {
 896         struct route_table *ntable;
 897         struct route_node *nrn;
 898         struct rnh *rnh;
 899
 900         if (IS_ZEBRA_DEBUG_NHT)
 901                 zlog_debug("%u: Client %s RNH cleanup for family %d type %d",
 902                            vrf_id, zebra_route_string(client->proto), family,
 903                            type);
 904
 905         ntable = get_rnh_table(vrf_id, family, type);
 906         if (!ntable) {
 907                 zlog_debug("cleanup_rnh_client: rnh table not found\n");
 908                 return -1;
 909         }
 910
 911         for (nrn = route_top(ntable); nrn; nrn = route_next(nrn)) {
 912                 if (!nrn->info)
 913                         continue;
 914
 915                 rnh = nrn->info;
 916                 zebra_remove_rnh_client(rnh, client, type);
 917         }
 918         return 1;
 919 }
 920
 921 /**
 922  * free_state - free up the re structure associated with the rnh.
 923  */
 924 static void free_state(vrf_id_t vrf_id, struct route_entry *re,
 925                        struct route_node *rn)
 926 {
 927
 928         if (!re)
 929                 return;
 930
 931         /* free RE and nexthops */
 932         zebra_deregister_rnh_static_nexthops(vrf_id, re->nexthop, rn);
 933         nexthops_free(re->nexthop);
 934         XFREE(MTYPE_RE, re);
 935 }
 936
 937 static void copy_state(struct rnh *rnh, struct route_entry *re,
 938                        struct route_node *rn)
 939 {
 940         struct route_entry *state;
 941
 942         if (rnh->state) {
 943                 free_state(rnh->vrf_id, rnh->state, rn);
 944                 rnh->state = NULL;
 945         }
 946
 947         if (!re)
 948                 return;
 949
 950         state = XCALLOC(MTYPE_RE, sizeof(struct route_entry));
 951         state->type = re->type;
 952         state->distance = re->distance;
 953         state->metric = re->metric;
 954
 955         route_entry_copy_nexthops(state, re->nexthop);
 956         rnh->state = state;
 957 }
 958
 959 static int compare_state(struct route_entry *r1, struct route_entry *r2)
 960 {
 961
 962         if (!r1 && !r2)
 963                 return 0;
 964
 965         if ((!r1 && r2) || (r1 && !r2))
 966                 return 1;
 967
 968         if (r1->distance != r2->distance)
 969                 return 1;
 970
 971         if (r1->metric != r2->metric)
 972                 return 1;
 973
 974         if (r1->nexthop_num != r2->nexthop_num)
 975                 return 1;
 976
 977         if (CHECK_FLAG(r1->status, ROUTE_ENTRY_NEXTHOPS_CHANGED)
 978             || CHECK_FLAG(r1->status, ROUTE_ENTRY_LABELS_CHANGED))
 979                 return 1;
 980
 981         return 0;
 982 }
 983
 984 static int send_client(struct rnh *rnh, struct zserv *client, rnh_type_t type,
 985                        vrf_id_t vrf_id)
 986 {
 987         struct stream *s;
 988         struct route_entry *re;
 989         unsigned long nump;
 990         u_char num;
 991         struct nexthop *nexthop;
 992         struct route_node *rn;
 993         int cmd = (type == RNH_IMPORT_CHECK_TYPE) ? ZEBRA_IMPORT_CHECK_UPDATE
 994                                                   : ZEBRA_NEXTHOP_UPDATE;
 995
 996         rn = rnh->node;
 997         re = rnh->state;
 998
 999         /* Get output stream. */
1000         s = client->obuf;
1001         stream_reset(s);
1002
1003         zclient_create_header(s, cmd, vrf_id);
1004
1005         stream_putw(s, rn->p.family);
1006         switch (rn->p.family) {
1007         case AF_INET:
1008                 stream_putc(s, rn->p.prefixlen);
1009                 stream_put_in_addr(s, &rn->p.u.prefix4);
1010                 break;
1011         case AF_INET6:
1012                 stream_putc(s, rn->p.prefixlen);
1013                 stream_put(s, &rn->p.u.prefix6, IPV6_MAX_BYTELEN);
1014                 break;
1015         default:
1016                 zlog_err("%s: Unknown family (%d) notification attempted\n",
1017                          __FUNCTION__, rn->p.family);
1018                 break;
1019         }
1020         if (re) {
1021                 stream_putc(s, re->distance);
1022                 stream_putl(s, re->metric);
1023                 num = 0;
1024                 nump = stream_get_endp(s);
1025                 stream_putc(s, 0);
1026                 for (nexthop = re->nexthop; nexthop; nexthop = nexthop->next)
1027                         if ((CHECK_FLAG(nexthop->flags, NEXTHOP_FLAG_FIB)
1028                              || CHECK_FLAG(nexthop->flags,
1029                                            NEXTHOP_FLAG_RECURSIVE))
1030                             && CHECK_FLAG(nexthop->flags,
1031                                           NEXTHOP_FLAG_ACTIVE)) {
1032                                 stream_putc(s, nexthop->type);
1033                                 switch (nexthop->type) {
1034                                 case NEXTHOP_TYPE_IPV4:
1035                                         stream_put_in_addr(s,
1036                                                            &nexthop->gate.ipv4);
1037                                         stream_putl(s, nexthop->ifindex);
1038                                         break;
1039                                 case NEXTHOP_TYPE_IFINDEX:
1040                                         stream_putl(s, nexthop->ifindex);
1041                                         break;
1042                                 case NEXTHOP_TYPE_IPV4_IFINDEX:
1043                                         stream_put_in_addr(s,
1044                                                            &nexthop->gate.ipv4);
1045                                         stream_putl(s, nexthop->ifindex);
1046                                         break;
1047                                 case NEXTHOP_TYPE_IPV6:
1048                                         stream_put(s, &nexthop->gate.ipv6, 16);
1049                                         stream_putl(s, nexthop->ifindex);
1050                                         break;
1051                                 case NEXTHOP_TYPE_IPV6_IFINDEX:
1052                                         stream_put(s, &nexthop->gate.ipv6, 16);
1053                                         stream_putl(s, nexthop->ifindex);
1054                                         break;
1055                                 default:
1056                                         /* do nothing */
1057                                         break;
1058                                 }
1059                                 num++;
1060                         }
1061                 stream_putc_at(s, nump, num);
1062         } else {
1063                 stream_putc(s, 0); // distance
1064                 stream_putl(s, 0); // metric
1065                 stream_putc(s, 0); // nexthops
1066         }
1067         stream_putw_at(s, 0, stream_get_endp(s));
1068
1069         client->nh_last_upd_time = monotime(NULL);
1070         client->last_write_cmd = cmd;
1071         return zebra_server_send_message(client);
1072 }
1073
1074 static void print_nh(struct nexthop *nexthop, struct vty *vty)
1075 {
1076         char buf[BUFSIZ];
1077         struct zebra_ns *zns = zebra_ns_lookup(NS_DEFAULT);
1078
1079         switch (nexthop->type) {
1080         case NEXTHOP_TYPE_IPV4:
1081         case NEXTHOP_TYPE_IPV4_IFINDEX:
1082                 vty_out(vty, " via %s", inet_ntoa(nexthop->gate.ipv4));
1083                 if (nexthop->ifindex)
1084                         vty_out(vty, ", %s",
1085                                 ifindex2ifname_per_ns(zns, nexthop->ifindex));
1086                 break;
1087         case NEXTHOP_TYPE_IPV6:
1088         case NEXTHOP_TYPE_IPV6_IFINDEX:
1089                 vty_out(vty, " %s",
1090                         inet_ntop(AF_INET6, &nexthop->gate.ipv6, buf, BUFSIZ));
1091                 if (nexthop->ifindex)
1092                         vty_out(vty, ", via %s",
1093                                 ifindex2ifname_per_ns(zns, nexthop->ifindex));
1094                 break;
1095         case NEXTHOP_TYPE_IFINDEX:
1096                 vty_out(vty, " is directly connected, %s",
1097                         ifindex2ifname_per_ns(zns, nexthop->ifindex));
1098                 break;
1099         case NEXTHOP_TYPE_BLACKHOLE:
1100                 vty_out(vty, " is directly connected, Null0");
1101                 break;
1102         default:
1103                 break;
1104         }
1105         vty_out(vty, "\n");
1106 }
1107
1108 static void print_rnh(struct route_node *rn, struct vty *vty)
1109 {
1110         struct rnh *rnh;
1111         struct nexthop *nexthop;
1112         struct listnode *node;
1113         struct zserv *client;
1114         char buf[BUFSIZ];
1115
1116         rnh = rn->info;
1117         vty_out(vty, "%s%s\n",
1118                 inet_ntop(rn->p.family, &rn->p.u.prefix, buf, BUFSIZ),
1119                 CHECK_FLAG(rnh->flags, ZEBRA_NHT_CONNECTED) ? "(Connected)"
1120                                                             : "");
1121         if (rnh->state) {
1122                 vty_out(vty, " resolved via %s\n",
1123                         zebra_route_string(rnh->state->type));
1124                 for (nexthop = rnh->state->nexthop; nexthop;
1125                      nexthop = nexthop->next)
1126                         print_nh(nexthop, vty);
1127         } else
1128                 vty_out(vty, " unresolved%s\n",
1129                         CHECK_FLAG(rnh->flags, ZEBRA_NHT_CONNECTED)
1130                                 ? "(Connected)"
1131                                 : "");
1132
1133         vty_out(vty, " Client list:");
1134         for (ALL_LIST_ELEMENTS_RO(rnh->client_list, node, client))
1135                 vty_out(vty, " %s(fd %d)%s", zebra_route_string(client->proto),
1136                         client->sock,
1137                         rnh->filtered[client->proto] ? "(filtered)" : "");
1138         if (!list_isempty(rnh->zebra_static_route_list))
1139                 vty_out(vty, " zebra%s",
1140                         rnh->filtered[ZEBRA_ROUTE_STATIC] ? "(filtered)" : "");
1141         if (!list_isempty(rnh->zebra_pseudowire_list))
1142                 vty_out(vty, " zebra[pseudowires]");
1143         vty_out(vty, "\n");
1144 }