zebra/rib.h

   1 /*
   2  * Routing Information Base header
   3  * Copyright (C) 1997 Kunihiro Ishiguro
   4  *
   5  * This file is part of GNU Zebra.
   6  *
   7  * GNU Zebra is free software; you can redistribute it and/or modify it
   8  * under the terms of the GNU General Public License as published by the
   9  * Free Software Foundation; either version 2, or (at your option) any
  10  * later version.
  11  *
  12  * GNU Zebra is distributed in the hope that it will be useful, but
  13  * WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License along
  18  * with this program; see the file COPYING; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
  20  */
  21
  22 #ifndef _ZEBRA_RIB_H
  23 #define _ZEBRA_RIB_H
  24
  25 #include "zebra.h"
  26 #include "hook.h"
  27 #include "typesafe.h"
  28 #include "linklist.h"
  29 #include "prefix.h"
  30 #include "table.h"
  31 #include "queue.h"
  32 #include "nexthop.h"
  33 #include "nexthop_group.h"
  34 #include "vrf.h"
  35 #include "if.h"
  36 #include "mpls.h"
  37 #include "srcdest_table.h"
  38 #include "zebra/zebra_nhg.h"
  39
  40 #ifdef __cplusplus
  41 extern "C" {
  42 #endif
  43
  44 enum rnh_type { RNH_NEXTHOP_TYPE, RNH_IMPORT_CHECK_TYPE };
  45
  46 PREDECL_LIST(rnh_list)
  47
  48 /* Nexthop structure. */
  49 struct rnh {
  50         uint8_t flags;
  51
  52 #define ZEBRA_NHT_CONNECTED     0x1
  53 #define ZEBRA_NHT_DELETED       0x2
  54 #define ZEBRA_NHT_EXACT_MATCH   0x4
  55
  56         /* VRF identifier. */
  57         vrf_id_t vrf_id;
  58
  59         afi_t afi;
  60
  61         enum rnh_type type;
  62
  63         uint32_t seqno;
  64
  65         struct route_entry *state;
  66         struct prefix resolved_route;
  67         struct list *client_list;
  68
  69         /* pseudowires dependent on this nh */
  70         struct list *zebra_pseudowire_list;
  71
  72         struct route_node *node;
  73
  74         /*
  75          * if this has been filtered for the client
  76          */
  77         int filtered[ZEBRA_ROUTE_MAX];
  78
  79         struct rnh_list_item rnh_list_item;
  80 };
  81
  82 #define DISTANCE_INFINITY  255
  83 #define ZEBRA_KERNEL_TABLE_MAX 252 /* support for no more than this rt tables */
  84
  85 PREDECL_LIST(re_list)
  86
  87 struct route_entry {
  88         /* Link list. */
  89         struct re_list_item next;
  90
  91         /* Nexthop group, shared/refcounted, based on the nexthop(s)
  92          * provided by the owner of the route
  93          */
  94         struct nhg_hash_entry *nhe;
  95
  96         /* Nexthop group from FIB (optional), reflecting what is actually
  97          * installed in the FIB if that differs. The 'backup' group is used
  98          * when backup nexthops are present in the route's nhg.
  99          */
 100         struct nexthop_group fib_ng;
 101         struct nexthop_group fib_backup_ng;
 102
 103         /* Nexthop group hash entry ID */
 104         uint32_t nhe_id;
 105
 106         /* Tag */
 107         route_tag_t tag;
 108
 109         /* Uptime. */
 110         time_t uptime;
 111
 112         /* Type of this route. */
 113         int type;
 114
 115         /* VRF identifier. */
 116         vrf_id_t vrf_id;
 117
 118         /* Which routing table */
 119         uint32_t table;
 120
 121         /* Metric */
 122         uint32_t metric;
 123
 124         /* MTU */
 125         uint32_t mtu;
 126         uint32_t nexthop_mtu;
 127
 128         /* Flags of this route.
 129          * This flag's definition is in lib/zebra.h ZEBRA_FLAG_* and is exposed
 130          * to clients via Zserv
 131          */
 132         uint32_t flags;
 133
 134         /* RIB internal status */
 135         uint32_t status;
 136 #define ROUTE_ENTRY_REMOVED          0x1
 137 /* The Route Entry has changed */
 138 #define ROUTE_ENTRY_CHANGED          0x2
 139 /* The Label has changed on the Route entry */
 140 #define ROUTE_ENTRY_LABELS_CHANGED   0x4
 141 /* Route is queued for Installation into the Data Plane */
 142 #define ROUTE_ENTRY_QUEUED   0x8
 143 /* Route is installed into the Data Plane */
 144 #define ROUTE_ENTRY_INSTALLED        0x10
 145 /* Route has Failed installation into the Data Plane in some manner */
 146 #define ROUTE_ENTRY_FAILED           0x20
 147 /* Route has a 'fib' set of nexthops, probably because the installed set
 148  * differs from the rib/normal set of nexthops.
 149  */
 150 #define ROUTE_ENTRY_USE_FIB_NHG      0x40
 151
 152         /* Sequence value incremented for each dataplane operation */
 153         uint32_t dplane_sequence;
 154
 155         /* Source protocol instance */
 156         uint16_t instance;
 157
 158         /* Distance. */
 159         uint8_t distance;
 160 };
 161
 162 #define RIB_SYSTEM_ROUTE(R) RSYSTEM_ROUTE((R)->type)
 163
 164 #define RIB_KERNEL_ROUTE(R) RKERNEL_ROUTE((R)->type)
 165
 166 /* meta-queue structure:
 167  * sub-queue 0: nexthop group objects
 168  * sub-queue 1: connected, kernel
 169  * sub-queue 2: static
 170  * sub-queue 3: RIP, RIPng, OSPF, OSPF6, IS-IS, EIGRP, NHRP
 171  * sub-queue 4: iBGP, eBGP
 172  * sub-queue 5: any other origin (if any)
 173  */
 174 #define MQ_SIZE 6
 175 struct meta_queue {
 176         struct list *subq[MQ_SIZE];
 177         uint32_t size; /* sum of lengths of all subqueues */
 178 };
 179
 180 /*
 181  * Structure that represents a single destination (prefix).
 182  */
 183 typedef struct rib_dest_t_ {
 184
 185         /*
 186          * Back pointer to the route node for this destination. This helps
 187          * us get to the prefix that this structure is for.
 188          */
 189         struct route_node *rnode;
 190
 191         /*
 192          * Doubly-linked list of routes for this prefix.
 193          */
 194         struct re_list_head routes;
 195
 196         struct route_entry *selected_fib;
 197
 198         /*
 199          * Flags, see below.
 200          */
 201         uint32_t flags;
 202
 203         /*
 204          * The list of nht prefixes that have ended up
 205          * depending on this route node.
 206          * After route processing is returned from
 207          * the data plane we will run evaluate_rnh
 208          * on these prefixes.
 209          */
 210         struct rnh_list_head nht;
 211
 212         /*
 213          * Linkage to put dest on the FPM processing queue.
 214          */
 215         TAILQ_ENTRY(rib_dest_t_) fpm_q_entries;
 216
 217 } rib_dest_t;
 218
 219 DECLARE_LIST(rnh_list, struct rnh, rnh_list_item);
 220 DECLARE_LIST(re_list, struct route_entry, next);
 221
 222 #define RIB_ROUTE_QUEUED(x)     (1 << (x))
 223 // If MQ_SIZE is modified this value needs to be updated.
 224 #define RIB_ROUTE_ANY_QUEUED 0x3F
 225
 226 /*
 227  * The maximum qindex that can be used.
 228  */
 229 #define ZEBRA_MAX_QINDEX        (MQ_SIZE - 1)
 230
 231 /*
 232  * This flag indicates that a given prefix has been 'advertised' to
 233  * the FPM to be installed in the forwarding plane.
 234  */
 235 #define RIB_DEST_SENT_TO_FPM   (1 << (ZEBRA_MAX_QINDEX + 1))
 236
 237 /*
 238  * This flag is set when we need to send an update to the FPM about a
 239  * dest.
 240  */
 241 #define RIB_DEST_UPDATE_FPM    (1 << (ZEBRA_MAX_QINDEX + 2))
 242
 243 #define RIB_DEST_UPDATE_LSPS   (1 << (ZEBRA_MAX_QINDEX + 3))
 244
 245 /*
 246  * Macro to iterate over each route for a destination (prefix).
 247  */
 248 #define RE_DEST_FOREACH_ROUTE(dest, re)                                        \
 249         for ((re) = (dest) ? re_list_first(&((dest)->routes)) : NULL; (re);    \
 250              (re) = re_list_next(&((dest)->routes), (re)))
 251
 252 /*
 253  * Same as above, but allows the current node to be unlinked.
 254  */
 255 #define RE_DEST_FOREACH_ROUTE_SAFE(dest, re, next)                             \
 256         for ((re) = (dest) ? re_list_first(&((dest)->routes)) : NULL;          \
 257              (re) && ((next) = re_list_next(&((dest)->routes), (re)), 1);      \
 258              (re) = (next))
 259
 260 #define RE_DEST_FIRST_ROUTE(dest, re)                                          \
 261         ((re) = (dest) ? re_list_first(&((dest)->routes)) : NULL)
 262
 263 #define RE_DEST_NEXT_ROUTE(dest, re)                                           \
 264         ((re) = (dest) ? re_list_next(&((dest)->routes), (re)) : NULL)
 265
 266 #define RNODE_FOREACH_RE(rn, re)                                               \
 267         RE_DEST_FOREACH_ROUTE (rib_dest_from_rnode(rn), re)
 268
 269 #define RNODE_FOREACH_RE_SAFE(rn, re, next)                                    \
 270         RE_DEST_FOREACH_ROUTE_SAFE (rib_dest_from_rnode(rn), re, next)
 271
 272 #define RNODE_FIRST_RE(rn, re) RE_DEST_FIRST_ROUTE(rib_dest_from_rnode(rn), re)
 273
 274 #define RNODE_NEXT_RE(rn, re) RE_DEST_NEXT_ROUTE(rib_dest_from_rnode(rn), re)
 275
 276 #if defined(HAVE_RTADV)
 277 /* Structure which hold status of router advertisement. */
 278 struct rtadv {
 279         int sock;
 280
 281         int adv_if_count;
 282         int adv_msec_if_count;
 283
 284         struct thread *ra_read;
 285         struct thread *ra_timer;
 286 };
 287 #endif /* HAVE_RTADV */
 288
 289 /*
 290  * rib_table_info_t
 291  *
 292  * Structure that is hung off of a route_table that holds information about
 293  * the table.
 294  */
 295 struct rib_table_info {
 296
 297         /*
 298          * Back pointer to zebra_vrf.
 299          */
 300         struct zebra_vrf *zvrf;
 301         afi_t afi;
 302         safi_t safi;
 303         uint32_t table_id;
 304 };
 305
 306 enum rib_tables_iter_state {
 307         RIB_TABLES_ITER_S_INIT,
 308         RIB_TABLES_ITER_S_ITERATING,
 309         RIB_TABLES_ITER_S_DONE
 310 };
 311
 312 /*
 313  * Structure that holds state for iterating over all tables in the
 314  * Routing Information Base.
 315  */
 316 typedef struct rib_tables_iter_t_ {
 317         vrf_id_t vrf_id;
 318         int afi_safi_ix;
 319
 320         enum rib_tables_iter_state state;
 321 } rib_tables_iter_t;
 322
 323 /* Events/reasons triggering a RIB update. */
 324 enum rib_update_event {
 325         RIB_UPDATE_KERNEL,
 326         RIB_UPDATE_RMAP_CHANGE,
 327         RIB_UPDATE_OTHER,
 328         RIB_UPDATE_MAX
 329 };
 330
 331 extern void route_entry_copy_nexthops(struct route_entry *re,
 332                                       struct nexthop *nh);
 333 int route_entry_update_nhe(struct route_entry *re,
 334                            struct nhg_hash_entry *new_nhghe);
 335
 336 /* NHG replace has happend, we have to update route_entry pointers to new one */
 337 void rib_handle_nhg_replace(struct nhg_hash_entry *old,
 338                             struct nhg_hash_entry *new);
 339
 340 #define route_entry_dump(prefix, src, re) _route_entry_dump(__func__, prefix, src, re)
 341 extern void _route_entry_dump(const char *func, union prefixconstptr pp,
 342                               union prefixconstptr src_pp,
 343                               const struct route_entry *re);
 344
 345 extern void rib_lookup_and_dump(struct prefix_ipv4 *p, vrf_id_t vrf_id);
 346 extern void rib_lookup_and_pushup(struct prefix_ipv4 *p, vrf_id_t vrf_id);
 347
 348 #define ZEBRA_RIB_LOOKUP_ERROR -1
 349 #define ZEBRA_RIB_FOUND_EXACT 0
 350 #define ZEBRA_RIB_FOUND_NOGATE 1
 351 #define ZEBRA_RIB_FOUND_CONNECTED 2
 352 #define ZEBRA_RIB_NOTFOUND 3
 353
 354 extern int is_zebra_valid_kernel_table(uint32_t table_id);
 355 extern int is_zebra_main_routing_table(uint32_t table_id);
 356 extern int zebra_check_addr(const struct prefix *p);
 357
 358 extern void rib_delnode(struct route_node *rn, struct route_entry *re);
 359 extern void rib_install_kernel(struct route_node *rn, struct route_entry *re,
 360                                struct route_entry *old);
 361 extern void rib_uninstall_kernel(struct route_node *rn, struct route_entry *re);
 362
 363 /* NOTE:
 364  * All rib_add function will not just add prefix into RIB, but
 365  * also implicitly withdraw equal prefix of same type. */
 366 extern int rib_add(afi_t afi, safi_t safi, vrf_id_t vrf_id, int type,
 367                    unsigned short instance, int flags, struct prefix *p,
 368                    struct prefix_ipv6 *src_p, const struct nexthop *nh,
 369                    uint32_t nhe_id, uint32_t table_id, uint32_t metric,
 370                    uint32_t mtu, uint8_t distance, route_tag_t tag);
 371 /*
 372  * Multipath route apis.
 373  */
 374 extern int rib_add_multipath(afi_t afi, safi_t safi, struct prefix *p,
 375                              struct prefix_ipv6 *src_p, struct route_entry *re,
 376                              struct nexthop_group *ng);
 377 extern int rib_add_multipath_nhe(afi_t afi, safi_t safi, struct prefix *p,
 378                                  struct prefix_ipv6 *src_p,
 379                                  struct route_entry *re,
 380                                  struct nhg_hash_entry *nhe);
 381
 382 extern void rib_delete(afi_t afi, safi_t safi, vrf_id_t vrf_id, int type,
 383                        unsigned short instance, int flags, struct prefix *p,
 384                        struct prefix_ipv6 *src_p, const struct nexthop *nh,
 385                        uint32_t nhe_id, uint32_t table_id, uint32_t metric,
 386                        uint8_t distance, bool fromkernel, bool connected_down);
 387
 388 extern struct route_entry *rib_match(afi_t afi, safi_t safi, vrf_id_t vrf_id,
 389                                      union g_addr *addr,
 390                                      struct route_node **rn_out);
 391 extern struct route_entry *rib_match_ipv4_multicast(vrf_id_t vrf_id,
 392                                                     struct in_addr addr,
 393                                                     struct route_node **rn_out);
 394
 395 extern struct route_entry *rib_lookup_ipv4(struct prefix_ipv4 *p,
 396                                            vrf_id_t vrf_id);
 397
 398 extern void rib_update(enum rib_update_event event);
 399 extern void rib_update_vrf(vrf_id_t vrf_id, enum rib_update_event event);
 400 extern void rib_update_table(struct route_table *table,
 401                              enum rib_update_event event);
 402 extern int rib_sweep_route(struct thread *t);
 403 extern void rib_sweep_table(struct route_table *table);
 404 extern void rib_close_table(struct route_table *table);
 405 extern void rib_init(void);
 406 extern unsigned long rib_score_proto(uint8_t proto, unsigned short instance);
 407 extern unsigned long rib_score_proto_table(uint8_t proto,
 408                                            unsigned short instance,
 409                                            struct route_table *table);
 410
 411 extern int rib_queue_add(struct route_node *rn);
 412
 413 struct nhg_ctx; /* Forward declaration */
 414
 415 extern int rib_queue_nhg_add(struct nhg_ctx *ctx);
 416
 417 extern void meta_queue_free(struct meta_queue *mq);
 418 extern int zebra_rib_labeled_unicast(struct route_entry *re);
 419 extern struct route_table *rib_table_ipv6;
 420
 421 extern void rib_unlink(struct route_node *rn, struct route_entry *re);
 422 extern int rib_gc_dest(struct route_node *rn);
 423 extern struct route_table *rib_tables_iter_next(rib_tables_iter_t *iter);
 424
 425 extern uint8_t route_distance(int type);
 426
 427 extern void zebra_rib_evaluate_rn_nexthops(struct route_node *rn, uint32_t seq);
 428
 429 /*
 430  * Inline functions.
 431  */
 432
 433 /*
 434  * rib_table_info
 435  */
 436 static inline struct rib_table_info *rib_table_info(struct route_table *table)
 437 {
 438         return (struct rib_table_info *)route_table_get_info(table);
 439 }
 440
 441 /*
 442  * rib_dest_from_rnode
 443  */
 444 static inline rib_dest_t *rib_dest_from_rnode(struct route_node *rn)
 445 {
 446         return (rib_dest_t *)rn->info;
 447 }
 448
 449 /*
 450  * rnode_to_ribs
 451  *
 452  * Returns a pointer to the list of routes corresponding to the given
 453  * route_node.
 454  */
 455 static inline struct route_entry *rnode_to_ribs(struct route_node *rn)
 456 {
 457         rib_dest_t *dest;
 458
 459         dest = rib_dest_from_rnode(rn);
 460         if (!dest)
 461                 return NULL;
 462
 463         return re_list_first(&dest->routes);
 464 }
 465
 466 /*
 467  * rib_dest_prefix
 468  */
 469 static inline struct prefix *rib_dest_prefix(rib_dest_t *dest)
 470 {
 471         return &dest->rnode->p;
 472 }
 473
 474 /*
 475  * rib_dest_af
 476  *
 477  * Returns the address family that the destination is for.
 478  */
 479 static inline uint8_t rib_dest_af(rib_dest_t *dest)
 480 {
 481         return dest->rnode->p.family;
 482 }
 483
 484 /*
 485  * rib_dest_table
 486  */
 487 static inline struct route_table *rib_dest_table(rib_dest_t *dest)
 488 {
 489         return srcdest_rnode_table(dest->rnode);
 490 }
 491
 492 /*
 493  * rib_dest_vrf
 494  */
 495 static inline struct zebra_vrf *rib_dest_vrf(rib_dest_t *dest)
 496 {
 497         return rib_table_info(rib_dest_table(dest))->zvrf;
 498 }
 499
 500 /*
 501  * Create the rib_dest_t and attach it to the specified node
 502  */
 503 extern rib_dest_t *zebra_rib_create_dest(struct route_node *rn);
 504
 505 /*
 506  * rib_tables_iter_init
 507  */
 508 static inline void rib_tables_iter_init(rib_tables_iter_t *iter)
 509
 510 {
 511         memset(iter, 0, sizeof(*iter));
 512         iter->state = RIB_TABLES_ITER_S_INIT;
 513 }
 514
 515 /*
 516  * rib_tables_iter_started
 517  *
 518  * Returns true if this iterator has started iterating over the set of
 519  * tables.
 520  */
 521 static inline int rib_tables_iter_started(rib_tables_iter_t *iter)
 522 {
 523         return iter->state != RIB_TABLES_ITER_S_INIT;
 524 }
 525
 526 /*
 527  * rib_tables_iter_cleanup
 528  */
 529 static inline void rib_tables_iter_cleanup(rib_tables_iter_t *iter)
 530 {
 531         iter->state = RIB_TABLES_ITER_S_DONE;
 532 }
 533
 534 DECLARE_HOOK(rib_update, (struct route_node * rn, const char *reason),
 535              (rn, reason))
 536
 537 /*
 538  * Access installed/fib nexthops, which may be a subset of the
 539  * rib nexthops.
 540  */
 541 static inline struct nexthop_group *rib_get_fib_nhg(struct route_entry *re)
 542 {
 543         /* If the fib set is a subset of the active rib set,
 544          * use the dedicated fib list.
 545          */
 546         if (CHECK_FLAG(re->status, ROUTE_ENTRY_USE_FIB_NHG))
 547                 return &(re->fib_ng);
 548         else
 549                 return &(re->nhe->nhg);
 550 }
 551
 552 /*
 553  * Access backup nexthop-group that represents the installed backup nexthops;
 554  * any installed backup will be on the fib list.
 555  */
 556 static inline struct nexthop_group *rib_get_fib_backup_nhg(
 557         struct route_entry *re)
 558 {
 559         return &(re->fib_backup_ng);
 560 }
 561
 562 extern void zebra_vty_init(void);
 563
 564 extern pid_t pid;
 565
 566 extern bool v6_rr_semantics;
 567
 568 #ifdef __cplusplus
 569 }
 570 #endif
 571
 572 #endif /*_ZEBRA_RIB_H */