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 opaque {
  88         uint16_t length;
  89         uint8_t data[];
  90 };
  91
  92 struct route_entry {
  93         /* Link list. */
  94         struct re_list_item next;
  95
  96         /* Nexthop group, shared/refcounted, based on the nexthop(s)
  97          * provided by the owner of the route
  98          */
  99         struct nhg_hash_entry *nhe;
 100
 101         /* Nexthop group from FIB (optional), reflecting what is actually
 102          * installed in the FIB if that differs. The 'backup' group is used
 103          * when backup nexthops are present in the route's nhg.
 104          */
 105         struct nexthop_group fib_ng;
 106         struct nexthop_group fib_backup_ng;
 107
 108         /* Nexthop group hash entry ID */
 109         uint32_t nhe_id;
 110
 111         /* Tag */
 112         route_tag_t tag;
 113
 114         /* Uptime. */
 115         time_t uptime;
 116
 117         /* Type of this route. */
 118         int type;
 119
 120         /* VRF identifier. */
 121         vrf_id_t vrf_id;
 122
 123         /* Which routing table */
 124         uint32_t table;
 125
 126         /* Metric */
 127         uint32_t metric;
 128
 129         /* MTU */
 130         uint32_t mtu;
 131         uint32_t nexthop_mtu;
 132
 133         /* Flags of this route.
 134          * This flag's definition is in lib/zebra.h ZEBRA_FLAG_* and is exposed
 135          * to clients via Zserv
 136          */
 137         uint32_t flags;
 138
 139         /* RIB internal status */
 140         uint32_t status;
 141 #define ROUTE_ENTRY_REMOVED          0x1
 142 /* The Route Entry has changed */
 143 #define ROUTE_ENTRY_CHANGED          0x2
 144 /* The Label has changed on the Route entry */
 145 #define ROUTE_ENTRY_LABELS_CHANGED   0x4
 146 /* Route is queued for Installation into the Data Plane */
 147 #define ROUTE_ENTRY_QUEUED   0x8
 148 /* Route is installed into the Data Plane */
 149 #define ROUTE_ENTRY_INSTALLED        0x10
 150 /* Route has Failed installation into the Data Plane in some manner */
 151 #define ROUTE_ENTRY_FAILED           0x20
 152 /* Route has a 'fib' set of nexthops, probably because the installed set
 153  * differs from the rib/normal set of nexthops.
 154  */
 155 #define ROUTE_ENTRY_USE_FIB_NHG      0x40
 156
 157         /* Sequence value incremented for each dataplane operation */
 158         uint32_t dplane_sequence;
 159
 160         /* Source protocol instance */
 161         uint16_t instance;
 162
 163         /* Distance. */
 164         uint8_t distance;
 165
 166         struct opaque *opaque;
 167 };
 168
 169 #define RIB_SYSTEM_ROUTE(R) RSYSTEM_ROUTE((R)->type)
 170
 171 #define RIB_KERNEL_ROUTE(R) RKERNEL_ROUTE((R)->type)
 172
 173 /* meta-queue structure:
 174  * sub-queue 0: nexthop group objects
 175  * sub-queue 1: connected
 176  * sub-queue 2: kernel
 177  * sub-queue 3: static
 178  * sub-queue 4: RIP, RIPng, OSPF, OSPF6, IS-IS, EIGRP, NHRP
 179  * sub-queue 5: iBGP, eBGP
 180  * sub-queue 6: any other origin (if any) typically those that
 181  *              don't generate routes
 182  */
 183 #define MQ_SIZE 7
 184 struct meta_queue {
 185         struct list *subq[MQ_SIZE];
 186         uint32_t size; /* sum of lengths of all subqueues */
 187 };
 188
 189 /*
 190  * Structure that represents a single destination (prefix).
 191  */
 192 typedef struct rib_dest_t_ {
 193
 194         /*
 195          * Back pointer to the route node for this destination. This helps
 196          * us get to the prefix that this structure is for.
 197          */
 198         struct route_node *rnode;
 199
 200         /*
 201          * Doubly-linked list of routes for this prefix.
 202          */
 203         struct re_list_head routes;
 204
 205         struct route_entry *selected_fib;
 206
 207         /*
 208          * Flags, see below.
 209          */
 210         uint32_t flags;
 211
 212         /*
 213          * The list of nht prefixes that have ended up
 214          * depending on this route node.
 215          * After route processing is returned from
 216          * the data plane we will run evaluate_rnh
 217          * on these prefixes.
 218          */
 219         struct rnh_list_head nht;
 220
 221         /*
 222          * Linkage to put dest on the FPM processing queue.
 223          */
 224         TAILQ_ENTRY(rib_dest_t_) fpm_q_entries;
 225
 226 } rib_dest_t;
 227
 228 DECLARE_LIST(rnh_list, struct rnh, rnh_list_item);
 229 DECLARE_LIST(re_list, struct route_entry, next);
 230
 231 #define RIB_ROUTE_QUEUED(x)     (1 << (x))
 232 // If MQ_SIZE is modified this value needs to be updated.
 233 #define RIB_ROUTE_ANY_QUEUED 0x3F
 234
 235 /*
 236  * The maximum qindex that can be used.
 237  */
 238 #define ZEBRA_MAX_QINDEX        (MQ_SIZE - 1)
 239
 240 /*
 241  * This flag indicates that a given prefix has been 'advertised' to
 242  * the FPM to be installed in the forwarding plane.
 243  */
 244 #define RIB_DEST_SENT_TO_FPM   (1 << (ZEBRA_MAX_QINDEX + 1))
 245
 246 /*
 247  * This flag is set when we need to send an update to the FPM about a
 248  * dest.
 249  */
 250 #define RIB_DEST_UPDATE_FPM    (1 << (ZEBRA_MAX_QINDEX + 2))
 251
 252 #define RIB_DEST_UPDATE_LSPS   (1 << (ZEBRA_MAX_QINDEX + 3))
 253
 254 /*
 255  * Macro to iterate over each route for a destination (prefix).
 256  */
 257 #define RE_DEST_FOREACH_ROUTE(dest, re)                                        \
 258         for ((re) = (dest) ? re_list_first(&((dest)->routes)) : NULL; (re);    \
 259              (re) = re_list_next(&((dest)->routes), (re)))
 260
 261 /*
 262  * Same as above, but allows the current node to be unlinked.
 263  */
 264 #define RE_DEST_FOREACH_ROUTE_SAFE(dest, re, next)                             \
 265         for ((re) = (dest) ? re_list_first(&((dest)->routes)) : NULL;          \
 266              (re) && ((next) = re_list_next(&((dest)->routes), (re)), 1);      \
 267              (re) = (next))
 268
 269 #define RE_DEST_FIRST_ROUTE(dest, re)                                          \
 270         ((re) = (dest) ? re_list_first(&((dest)->routes)) : NULL)
 271
 272 #define RE_DEST_NEXT_ROUTE(dest, re)                                           \
 273         ((re) = (dest) ? re_list_next(&((dest)->routes), (re)) : NULL)
 274
 275 #define RNODE_FOREACH_RE(rn, re)                                               \
 276         RE_DEST_FOREACH_ROUTE (rib_dest_from_rnode(rn), re)
 277
 278 #define RNODE_FOREACH_RE_SAFE(rn, re, next)                                    \
 279         RE_DEST_FOREACH_ROUTE_SAFE (rib_dest_from_rnode(rn), re, next)
 280
 281 #define RNODE_FIRST_RE(rn, re) RE_DEST_FIRST_ROUTE(rib_dest_from_rnode(rn), re)
 282
 283 #define RNODE_NEXT_RE(rn, re) RE_DEST_NEXT_ROUTE(rib_dest_from_rnode(rn), re)
 284
 285 #if defined(HAVE_RTADV)
 286 /* Structure which hold status of router advertisement. */
 287 struct rtadv {
 288         int sock;
 289
 290         int adv_if_count;
 291         int adv_msec_if_count;
 292
 293         struct thread *ra_read;
 294         struct thread *ra_timer;
 295 };
 296 #endif /* HAVE_RTADV */
 297
 298 /*
 299  * rib_table_info_t
 300  *
 301  * Structure that is hung off of a route_table that holds information about
 302  * the table.
 303  */
 304 struct rib_table_info {
 305
 306         /*
 307          * Back pointer to zebra_vrf.
 308          */
 309         struct zebra_vrf *zvrf;
 310         afi_t afi;
 311         safi_t safi;
 312         uint32_t table_id;
 313 };
 314
 315 enum rib_tables_iter_state {
 316         RIB_TABLES_ITER_S_INIT,
 317         RIB_TABLES_ITER_S_ITERATING,
 318         RIB_TABLES_ITER_S_DONE
 319 };
 320
 321 /*
 322  * Structure that holds state for iterating over all tables in the
 323  * Routing Information Base.
 324  */
 325 typedef struct rib_tables_iter_t_ {
 326         vrf_id_t vrf_id;
 327         int afi_safi_ix;
 328
 329         enum rib_tables_iter_state state;
 330 } rib_tables_iter_t;
 331
 332 /* Events/reasons triggering a RIB update. */
 333 enum rib_update_event {
 334         RIB_UPDATE_KERNEL,
 335         RIB_UPDATE_RMAP_CHANGE,
 336         RIB_UPDATE_OTHER,
 337         RIB_UPDATE_MAX
 338 };
 339
 340 extern void route_entry_copy_nexthops(struct route_entry *re,
 341                                       struct nexthop *nh);
 342 int route_entry_update_nhe(struct route_entry *re,
 343                            struct nhg_hash_entry *new_nhghe);
 344
 345 /* NHG replace has happend, we have to update route_entry pointers to new one */
 346 void rib_handle_nhg_replace(struct nhg_hash_entry *old,
 347                             struct nhg_hash_entry *new);
 348
 349 #define route_entry_dump(prefix, src, re) _route_entry_dump(__func__, prefix, src, re)
 350 extern void _route_entry_dump(const char *func, union prefixconstptr pp,
 351                               union prefixconstptr src_pp,
 352                               const struct route_entry *re);
 353
 354 extern void rib_lookup_and_dump(struct prefix_ipv4 *p, vrf_id_t vrf_id);
 355 extern void rib_lookup_and_pushup(struct prefix_ipv4 *p, vrf_id_t vrf_id);
 356
 357 #define ZEBRA_RIB_LOOKUP_ERROR -1
 358 #define ZEBRA_RIB_FOUND_EXACT 0
 359 #define ZEBRA_RIB_FOUND_NOGATE 1
 360 #define ZEBRA_RIB_FOUND_CONNECTED 2
 361 #define ZEBRA_RIB_NOTFOUND 3
 362
 363 extern int is_zebra_valid_kernel_table(uint32_t table_id);
 364 extern int is_zebra_main_routing_table(uint32_t table_id);
 365 extern int zebra_check_addr(const struct prefix *p);
 366
 367 extern void rib_delnode(struct route_node *rn, struct route_entry *re);
 368 extern void rib_install_kernel(struct route_node *rn, struct route_entry *re,
 369                                struct route_entry *old);
 370 extern void rib_uninstall_kernel(struct route_node *rn, struct route_entry *re);
 371
 372 /* NOTE:
 373  * All rib_add function will not just add prefix into RIB, but
 374  * also implicitly withdraw equal prefix of same type. */
 375 extern int rib_add(afi_t afi, safi_t safi, vrf_id_t vrf_id, int type,
 376                    unsigned short instance, uint32_t flags, struct prefix *p,
 377                    struct prefix_ipv6 *src_p, const struct nexthop *nh,
 378                    uint32_t nhe_id, uint32_t table_id, uint32_t metric,
 379                    uint32_t mtu, uint8_t distance, route_tag_t tag);
 380 /*
 381  * Multipath route apis.
 382  */
 383 extern int rib_add_multipath(afi_t afi, safi_t safi, struct prefix *p,
 384                              struct prefix_ipv6 *src_p, struct route_entry *re,
 385                              struct nexthop_group *ng);
 386 extern int rib_add_multipath_nhe(afi_t afi, safi_t safi, struct prefix *p,
 387                                  struct prefix_ipv6 *src_p,
 388                                  struct route_entry *re,
 389                                  struct nhg_hash_entry *nhe);
 390
 391 extern void rib_delete(afi_t afi, safi_t safi, vrf_id_t vrf_id, int type,
 392                        unsigned short instance, uint32_t flags,
 393                        struct prefix *p, struct prefix_ipv6 *src_p,
 394                        const struct nexthop *nh, uint32_t nhe_id,
 395                        uint32_t table_id, uint32_t metric, uint8_t distance,
 396                        bool fromkernel, bool connected_down);
 397
 398 extern struct route_entry *rib_match(afi_t afi, safi_t safi, vrf_id_t vrf_id,
 399                                      union g_addr *addr,
 400                                      struct route_node **rn_out);
 401 extern struct route_entry *rib_match_ipv4_multicast(vrf_id_t vrf_id,
 402                                                     struct in_addr addr,
 403                                                     struct route_node **rn_out);
 404
 405 extern struct route_entry *rib_lookup_ipv4(struct prefix_ipv4 *p,
 406                                            vrf_id_t vrf_id);
 407
 408 extern void rib_update(enum rib_update_event event);
 409 extern void rib_update_vrf(vrf_id_t vrf_id, enum rib_update_event event);
 410 extern void rib_update_table(struct route_table *table,
 411                              enum rib_update_event event);
 412 extern int rib_sweep_route(struct thread *t);
 413 extern void rib_sweep_table(struct route_table *table);
 414 extern void rib_close_table(struct route_table *table);
 415 extern void rib_init(void);
 416 extern unsigned long rib_score_proto(uint8_t proto, unsigned short instance);
 417 extern unsigned long rib_score_proto_table(uint8_t proto,
 418                                            unsigned short instance,
 419                                            struct route_table *table);
 420
 421 extern int rib_queue_add(struct route_node *rn);
 422
 423 struct nhg_ctx; /* Forward declaration */
 424
 425 extern int rib_queue_nhg_add(struct nhg_ctx *ctx);
 426
 427 extern void meta_queue_free(struct meta_queue *mq);
 428 extern int zebra_rib_labeled_unicast(struct route_entry *re);
 429 extern struct route_table *rib_table_ipv6;
 430
 431 extern void rib_unlink(struct route_node *rn, struct route_entry *re);
 432 extern int rib_gc_dest(struct route_node *rn);
 433 extern struct route_table *rib_tables_iter_next(rib_tables_iter_t *iter);
 434
 435 extern uint8_t route_distance(int type);
 436
 437 extern void zebra_rib_evaluate_rn_nexthops(struct route_node *rn, uint32_t seq);
 438
 439 /*
 440  * Inline functions.
 441  */
 442
 443 /*
 444  * rib_table_info
 445  */
 446 static inline struct rib_table_info *rib_table_info(struct route_table *table)
 447 {
 448         return (struct rib_table_info *)route_table_get_info(table);
 449 }
 450
 451 /*
 452  * rib_dest_from_rnode
 453  */
 454 static inline rib_dest_t *rib_dest_from_rnode(struct route_node *rn)
 455 {
 456         return (rib_dest_t *)rn->info;
 457 }
 458
 459 /*
 460  * rnode_to_ribs
 461  *
 462  * Returns a pointer to the list of routes corresponding to the given
 463  * route_node.
 464  */
 465 static inline struct route_entry *rnode_to_ribs(struct route_node *rn)
 466 {
 467         rib_dest_t *dest;
 468
 469         dest = rib_dest_from_rnode(rn);
 470         if (!dest)
 471                 return NULL;
 472
 473         return re_list_first(&dest->routes);
 474 }
 475
 476 /*
 477  * rib_dest_prefix
 478  */
 479 static inline struct prefix *rib_dest_prefix(rib_dest_t *dest)
 480 {
 481         return &dest->rnode->p;
 482 }
 483
 484 /*
 485  * rib_dest_af
 486  *
 487  * Returns the address family that the destination is for.
 488  */
 489 static inline uint8_t rib_dest_af(rib_dest_t *dest)
 490 {
 491         return dest->rnode->p.family;
 492 }
 493
 494 /*
 495  * rib_dest_table
 496  */
 497 static inline struct route_table *rib_dest_table(rib_dest_t *dest)
 498 {
 499         return srcdest_rnode_table(dest->rnode);
 500 }
 501
 502 /*
 503  * rib_dest_vrf
 504  */
 505 static inline struct zebra_vrf *rib_dest_vrf(rib_dest_t *dest)
 506 {
 507         return rib_table_info(rib_dest_table(dest))->zvrf;
 508 }
 509
 510 /*
 511  * Create the rib_dest_t and attach it to the specified node
 512  */
 513 extern rib_dest_t *zebra_rib_create_dest(struct route_node *rn);
 514
 515 /*
 516  * rib_tables_iter_init
 517  */
 518 static inline void rib_tables_iter_init(rib_tables_iter_t *iter)
 519
 520 {
 521         memset(iter, 0, sizeof(*iter));
 522         iter->state = RIB_TABLES_ITER_S_INIT;
 523 }
 524
 525 /*
 526  * rib_tables_iter_started
 527  *
 528  * Returns true if this iterator has started iterating over the set of
 529  * tables.
 530  */
 531 static inline int rib_tables_iter_started(rib_tables_iter_t *iter)
 532 {
 533         return iter->state != RIB_TABLES_ITER_S_INIT;
 534 }
 535
 536 /*
 537  * rib_tables_iter_cleanup
 538  */
 539 static inline void rib_tables_iter_cleanup(rib_tables_iter_t *iter)
 540 {
 541         iter->state = RIB_TABLES_ITER_S_DONE;
 542 }
 543
 544 DECLARE_HOOK(rib_update, (struct route_node * rn, const char *reason),
 545              (rn, reason))
 546
 547 /*
 548  * Access installed/fib nexthops, which may be a subset of the
 549  * rib nexthops.
 550  */
 551 static inline struct nexthop_group *rib_get_fib_nhg(struct route_entry *re)
 552 {
 553         /* If the fib set is a subset of the active rib set,
 554          * use the dedicated fib list.
 555          */
 556         if (CHECK_FLAG(re->status, ROUTE_ENTRY_USE_FIB_NHG))
 557                 return &(re->fib_ng);
 558         else
 559                 return &(re->nhe->nhg);
 560 }
 561
 562 /*
 563  * Access backup nexthop-group that represents the installed backup nexthops;
 564  * any installed backup will be on the fib list.
 565  */
 566 static inline struct nexthop_group *rib_get_fib_backup_nhg(
 567         struct route_entry *re)
 568 {
 569         return &(re->fib_backup_ng);
 570 }
 571
 572 extern void zebra_vty_init(void);
 573
 574 extern pid_t pid;
 575
 576 extern bool v6_rr_semantics;
 577
 578 #ifdef __cplusplus
 579 }
 580 #endif
 581
 582 #endif /*_ZEBRA_RIB_H */