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 "linklist.h"
  28 #include "prefix.h"
  29 #include "table.h"
  30 #include "queue.h"
  31 #include "nexthop.h"
  32 #include "nexthop_group.h"
  33 #include "vrf.h"
  34 #include "if.h"
  35 #include "mpls.h"
  36 #include "srcdest_table.h"
  37
  38 #ifdef __cplusplus
  39 extern "C" {
  40 #endif
  41
  42 #define DISTANCE_INFINITY  255
  43 #define ZEBRA_KERNEL_TABLE_MAX 252 /* support for no more than this rt tables */
  44
  45 struct route_entry {
  46         /* Link list. */
  47         struct route_entry *next;
  48         struct route_entry *prev;
  49
  50         /* Nexthop structure */
  51         struct nexthop_group ng;
  52
  53         /* Tag */
  54         route_tag_t tag;
  55
  56         /* Uptime. */
  57         time_t uptime;
  58
  59         /* Type fo this route. */
  60         int type;
  61
  62         /* Source protocol instance */
  63         unsigned short instance;
  64
  65         /* VRF identifier. */
  66         vrf_id_t vrf_id;
  67
  68         /* Which routing table */
  69         uint32_t table;
  70
  71         /* Metric */
  72         uint32_t metric;
  73
  74         /* MTU */
  75         uint32_t mtu;
  76         uint32_t nexthop_mtu;
  77
  78         /* Distance. */
  79         uint8_t distance;
  80
  81         /* Flags of this route.
  82          * This flag's definition is in lib/zebra.h ZEBRA_FLAG_* and is exposed
  83          * to clients via Zserv
  84          */
  85         uint32_t flags;
  86
  87         /* RIB internal status */
  88         uint32_t status;
  89 #define ROUTE_ENTRY_REMOVED          0x1
  90 /* to simplify NHT logic when NHs change, instead of doing a NH by NH cmp */
  91 #define ROUTE_ENTRY_NEXTHOPS_CHANGED 0x2
  92 /* The Route Entry has changed */
  93 #define ROUTE_ENTRY_CHANGED          0x4
  94 /* The Label has changed on the Route entry */
  95 #define ROUTE_ENTRY_LABELS_CHANGED   0x8
  96 /* Route is queued for Installation into the Data Plane */
  97 #define ROUTE_ENTRY_QUEUED   0x10
  98 /* Route is installed into the Data Plane */
  99 #define ROUTE_ENTRY_INSTALLED        0x20
 100 /* Route has Failed installation into the Data Plane in some manner */
 101 #define ROUTE_ENTRY_FAILED           0x40
 102
 103         /* Nexthop information. */
 104         uint8_t nexthop_num;
 105         uint8_t nexthop_active_num;
 106
 107         /* Sequence value incremented for each dataplane operation */
 108         uint32_t dplane_sequence;
 109 };
 110
 111 /* meta-queue structure:
 112  * sub-queue 0: connected, kernel
 113  * sub-queue 1: static
 114  * sub-queue 2: RIP, RIPng, OSPF, OSPF6, IS-IS, EIGRP, NHRP
 115  * sub-queue 3: iBGP, eBGP
 116  * sub-queue 4: any other origin (if any)
 117  */
 118 #define MQ_SIZE 5
 119 struct meta_queue {
 120         struct list *subq[MQ_SIZE];
 121         uint32_t size; /* sum of lengths of all subqueues */
 122 };
 123
 124 /*
 125  * Structure that represents a single destination (prefix).
 126  */
 127 typedef struct rib_dest_t_ {
 128
 129         /*
 130          * Back pointer to the route node for this destination. This helps
 131          * us get to the prefix that this structure is for.
 132          */
 133         struct route_node *rnode;
 134
 135         /*
 136          * Doubly-linked list of routes for this prefix.
 137          */
 138         struct route_entry *routes;
 139
 140         struct route_entry *selected_fib;
 141
 142         /*
 143          * Flags, see below.
 144          */
 145         uint32_t flags;
 146
 147         /*
 148          * The list of nht prefixes that have ended up
 149          * depending on this route node.
 150          * After route processing is returned from
 151          * the data plane we will run evaluate_rnh
 152          * on these prefixes.
 153          */
 154         struct list *nht;
 155
 156         /*
 157          * Linkage to put dest on the FPM processing queue.
 158          */
 159         TAILQ_ENTRY(rib_dest_t_) fpm_q_entries;
 160
 161 } rib_dest_t;
 162
 163 #define RIB_ROUTE_QUEUED(x)     (1 << (x))
 164 // If MQ_SIZE is modified this value needs to be updated.
 165 #define RIB_ROUTE_ANY_QUEUED    0x1F
 166
 167 /*
 168  * The maximum qindex that can be used.
 169  */
 170 #define ZEBRA_MAX_QINDEX        (MQ_SIZE - 1)
 171
 172 /*
 173  * This flag indicates that a given prefix has been 'advertised' to
 174  * the FPM to be installed in the forwarding plane.
 175  */
 176 #define RIB_DEST_SENT_TO_FPM   (1 << (ZEBRA_MAX_QINDEX + 1))
 177
 178 /*
 179  * This flag is set when we need to send an update to the FPM about a
 180  * dest.
 181  */
 182 #define RIB_DEST_UPDATE_FPM    (1 << (ZEBRA_MAX_QINDEX + 2))
 183
 184 /*
 185  * Macro to iterate over each route for a destination (prefix).
 186  */
 187 #define RE_DEST_FOREACH_ROUTE(dest, re)                                        \
 188         for ((re) = (dest) ? (dest)->routes : NULL; (re); (re) = (re)->next)
 189
 190 /*
 191  * Same as above, but allows the current node to be unlinked.
 192  */
 193 #define RE_DEST_FOREACH_ROUTE_SAFE(dest, re, next)                             \
 194         for ((re) = (dest) ? (dest)->routes : NULL;                            \
 195              (re) && ((next) = (re)->next, 1); (re) = (next))
 196
 197 #define RNODE_FOREACH_RE(rn, re)                                               \
 198         RE_DEST_FOREACH_ROUTE (rib_dest_from_rnode(rn), re)
 199
 200 #define RNODE_FOREACH_RE_SAFE(rn, re, next)                                    \
 201         RE_DEST_FOREACH_ROUTE_SAFE (rib_dest_from_rnode(rn), re, next)
 202
 203 #if defined(HAVE_RTADV)
 204 /* Structure which hold status of router advertisement. */
 205 struct rtadv {
 206         int sock;
 207
 208         int adv_if_count;
 209         int adv_msec_if_count;
 210
 211         struct thread *ra_read;
 212         struct thread *ra_timer;
 213 };
 214 #endif /* HAVE_RTADV */
 215
 216 /*
 217  * rib_table_info_t
 218  *
 219  * Structure that is hung off of a route_table that holds information about
 220  * the table.
 221  */
 222 typedef struct rib_table_info_t_ {
 223
 224         /*
 225          * Back pointer to zebra_vrf.
 226          */
 227         struct zebra_vrf *zvrf;
 228         afi_t afi;
 229         safi_t safi;
 230
 231 } rib_table_info_t;
 232
 233 typedef enum {
 234         RIB_TABLES_ITER_S_INIT,
 235         RIB_TABLES_ITER_S_ITERATING,
 236         RIB_TABLES_ITER_S_DONE
 237 } rib_tables_iter_state_t;
 238
 239 /*
 240  * Structure that holds state for iterating over all tables in the
 241  * Routing Information Base.
 242  */
 243 typedef struct rib_tables_iter_t_ {
 244         vrf_id_t vrf_id;
 245         int afi_safi_ix;
 246
 247         rib_tables_iter_state_t state;
 248 } rib_tables_iter_t;
 249
 250 /* Events/reasons triggering a RIB update. */
 251 typedef enum {
 252         RIB_UPDATE_IF_CHANGE,
 253         RIB_UPDATE_RMAP_CHANGE,
 254         RIB_UPDATE_OTHER
 255 } rib_update_event_t;
 256
 257 extern struct nexthop *route_entry_nexthop_ifindex_add(struct route_entry *re,
 258                                                        ifindex_t ifindex,
 259                                                        vrf_id_t nh_vrf_id);
 260 extern struct nexthop *
 261 route_entry_nexthop_blackhole_add(struct route_entry *re,
 262                                   enum blackhole_type bh_type);
 263 extern struct nexthop *route_entry_nexthop_ipv4_add(struct route_entry *re,
 264                                                     struct in_addr *ipv4,
 265                                                     struct in_addr *src,
 266                                                     vrf_id_t nh_vrf_id);
 267 extern struct nexthop *
 268 route_entry_nexthop_ipv4_ifindex_add(struct route_entry *re,
 269                                      struct in_addr *ipv4, struct in_addr *src,
 270                                      ifindex_t ifindex, vrf_id_t nh_vrf_id);
 271 extern void route_entry_nexthop_delete(struct route_entry *re,
 272                                        struct nexthop *nexthop);
 273 extern struct nexthop *route_entry_nexthop_ipv6_add(struct route_entry *re,
 274                                                     struct in6_addr *ipv6,
 275                                                     vrf_id_t nh_vrf_id);
 276 extern struct nexthop *
 277 route_entry_nexthop_ipv6_ifindex_add(struct route_entry *re,
 278                                      struct in6_addr *ipv6, ifindex_t ifindex,
 279                                      vrf_id_t nh_vrf_id);
 280 extern void route_entry_nexthop_add(struct route_entry *re,
 281                                     struct nexthop *nexthop);
 282 extern void route_entry_copy_nexthops(struct route_entry *re,
 283                                       struct nexthop *nh);
 284
 285 #define route_entry_dump(prefix, src, re) _route_entry_dump(__func__, prefix, src, re)
 286 extern void _route_entry_dump(const char *func, union prefixconstptr pp,
 287                               union prefixconstptr src_pp,
 288                               const struct route_entry *re);
 289 /* RPF lookup behaviour */
 290 enum multicast_mode {
 291         MCAST_NO_CONFIG = 0,  /* MIX_MRIB_FIRST, but no show in config write */
 292         MCAST_MRIB_ONLY,      /* MRIB only */
 293         MCAST_URIB_ONLY,      /* URIB only */
 294         MCAST_MIX_MRIB_FIRST, /* MRIB, if nothing at all then URIB */
 295         MCAST_MIX_DISTANCE,   /* MRIB & URIB, lower distance wins */
 296         MCAST_MIX_PFXLEN,     /* MRIB & URIB, longer prefix wins */
 297                               /* on equal value, MRIB wins for last 2 */
 298 };
 299
 300 extern void multicast_mode_ipv4_set(enum multicast_mode mode);
 301 extern enum multicast_mode multicast_mode_ipv4_get(void);
 302
 303 extern void rib_lookup_and_dump(struct prefix_ipv4 *p, vrf_id_t vrf_id);
 304 extern void rib_lookup_and_pushup(struct prefix_ipv4 *p, vrf_id_t vrf_id);
 305
 306 #define ZEBRA_RIB_LOOKUP_ERROR -1
 307 #define ZEBRA_RIB_FOUND_EXACT 0
 308 #define ZEBRA_RIB_FOUND_NOGATE 1
 309 #define ZEBRA_RIB_FOUND_CONNECTED 2
 310 #define ZEBRA_RIB_NOTFOUND 3
 311
 312 extern int is_zebra_valid_kernel_table(uint32_t table_id);
 313 extern int is_zebra_main_routing_table(uint32_t table_id);
 314 extern int zebra_check_addr(const struct prefix *p);
 315
 316 extern void rib_delnode(struct route_node *rn, struct route_entry *re);
 317 extern void rib_install_kernel(struct route_node *rn, struct route_entry *re,
 318                                struct route_entry *old);
 319 extern void rib_uninstall_kernel(struct route_node *rn, struct route_entry *re);
 320
 321 /* NOTE:
 322  * All rib_add function will not just add prefix into RIB, but
 323  * also implicitly withdraw equal prefix of same type. */
 324 extern int rib_add(afi_t afi, safi_t safi, vrf_id_t vrf_id, int type,
 325                    unsigned short instance, int flags, struct prefix *p,
 326                    struct prefix_ipv6 *src_p, const struct nexthop *nh,
 327                    uint32_t table_id, uint32_t metric, uint32_t mtu,
 328                    uint8_t distance, route_tag_t tag);
 329
 330 extern int rib_add_multipath(afi_t afi, safi_t safi, struct prefix *p,
 331                              struct prefix_ipv6 *src_p, struct route_entry *re);
 332
 333 extern void rib_delete(afi_t afi, safi_t safi, vrf_id_t vrf_id, int type,
 334                        unsigned short instance, int flags, struct prefix *p,
 335                        struct prefix_ipv6 *src_p, const struct nexthop *nh,
 336                        uint32_t table_id, uint32_t metric, uint8_t distance,
 337                        bool fromkernel);
 338
 339 extern struct route_entry *rib_match(afi_t afi, safi_t safi, vrf_id_t vrf_id,
 340                                      union g_addr *addr,
 341                                      struct route_node **rn_out);
 342 extern struct route_entry *rib_match_ipv4_multicast(vrf_id_t vrf_id,
 343                                                     struct in_addr addr,
 344                                                     struct route_node **rn_out);
 345
 346 extern struct route_entry *rib_lookup_ipv4(struct prefix_ipv4 *p,
 347                                            vrf_id_t vrf_id);
 348
 349 extern void rib_update(vrf_id_t vrf_id, rib_update_event_t event);
 350 extern void rib_update_table(struct route_table *table,
 351                              rib_update_event_t event);
 352 extern void rib_sweep_route(void);
 353 extern void rib_sweep_table(struct route_table *table);
 354 extern void rib_close_table(struct route_table *table);
 355 extern void rib_init(void);
 356 extern unsigned long rib_score_proto(uint8_t proto, unsigned short instance);
 357 extern unsigned long rib_score_proto_table(uint8_t proto,
 358                                            unsigned short instance,
 359                                            struct route_table *table);
 360 extern void rib_queue_add(struct route_node *rn);
 361 extern void meta_queue_free(struct meta_queue *mq);
 362 extern int zebra_rib_labeled_unicast(struct route_entry *re);
 363 extern struct route_table *rib_table_ipv6;
 364
 365 extern void rib_unlink(struct route_node *rn, struct route_entry *re);
 366 extern int rib_gc_dest(struct route_node *rn);
 367 extern struct route_table *rib_tables_iter_next(rib_tables_iter_t *iter);
 368
 369 extern uint8_t route_distance(int type);
 370
 371 extern void zebra_rib_evaluate_rn_nexthops(struct route_node *rn, uint32_t seq);
 372
 373 /*
 374  * Inline functions.
 375  */
 376
 377 /*
 378  * rib_table_info
 379  */
 380 static inline rib_table_info_t *rib_table_info(struct route_table *table)
 381 {
 382         return (rib_table_info_t *)route_table_get_info(table);
 383 }
 384
 385 /*
 386  * rib_dest_from_rnode
 387  */
 388 static inline rib_dest_t *rib_dest_from_rnode(struct route_node *rn)
 389 {
 390         return (rib_dest_t *)rn->info;
 391 }
 392
 393 /*
 394  * rnode_to_ribs
 395  *
 396  * Returns a pointer to the list of routes corresponding to the given
 397  * route_node.
 398  */
 399 static inline struct route_entry *rnode_to_ribs(struct route_node *rn)
 400 {
 401         rib_dest_t *dest;
 402
 403         dest = rib_dest_from_rnode(rn);
 404         if (!dest)
 405                 return NULL;
 406
 407         return dest->routes;
 408 }
 409
 410 /*
 411  * rib_dest_prefix
 412  */
 413 static inline struct prefix *rib_dest_prefix(rib_dest_t *dest)
 414 {
 415         return &dest->rnode->p;
 416 }
 417
 418 /*
 419  * rib_dest_af
 420  *
 421  * Returns the address family that the destination is for.
 422  */
 423 static inline uint8_t rib_dest_af(rib_dest_t *dest)
 424 {
 425         return dest->rnode->p.family;
 426 }
 427
 428 /*
 429  * rib_dest_table
 430  */
 431 static inline struct route_table *rib_dest_table(rib_dest_t *dest)
 432 {
 433         return srcdest_rnode_table(dest->rnode);
 434 }
 435
 436 /*
 437  * rib_dest_vrf
 438  */
 439 static inline struct zebra_vrf *rib_dest_vrf(rib_dest_t *dest)
 440 {
 441         return rib_table_info(rib_dest_table(dest))->zvrf;
 442 }
 443
 444 /*
 445  * Create the rib_dest_t and attach it to the specified node
 446  */
 447 extern rib_dest_t *zebra_rib_create_dest(struct route_node *rn);
 448
 449 /*
 450  * rib_tables_iter_init
 451  */
 452 static inline void rib_tables_iter_init(rib_tables_iter_t *iter)
 453
 454 {
 455         memset(iter, 0, sizeof(*iter));
 456         iter->state = RIB_TABLES_ITER_S_INIT;
 457 }
 458
 459 /*
 460  * rib_tables_iter_started
 461  *
 462  * Returns TRUE if this iterator has started iterating over the set of
 463  * tables.
 464  */
 465 static inline int rib_tables_iter_started(rib_tables_iter_t *iter)
 466 {
 467         return iter->state != RIB_TABLES_ITER_S_INIT;
 468 }
 469
 470 /*
 471  * rib_tables_iter_cleanup
 472  */
 473 static inline void rib_tables_iter_cleanup(rib_tables_iter_t *iter)
 474 {
 475         iter->state = RIB_TABLES_ITER_S_DONE;
 476 }
 477
 478 DECLARE_HOOK(rib_update, (struct route_node * rn, const char *reason),
 479              (rn, reason))
 480
 481
 482 extern void zebra_vty_init(void);
 483
 484 extern pid_t pid;
 485
 486 extern bool v6_rr_semantics;
 487
 488 #ifdef __cplusplus
 489 }
 490 #endif
 491
 492 #endif /*_ZEBRA_RIB_H */