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 "vrf.h"
  33 #include "if.h"
  34 #include "mpls.h"
  35 #include "srcdest_table.h"
  36
  37 #define DISTANCE_INFINITY  255
  38 #define ZEBRA_KERNEL_TABLE_MAX 252 /* support for no more than this rt tables */
  39
  40 struct route_entry {
  41         /* Link list. */
  42         struct route_entry *next;
  43         struct route_entry *prev;
  44
  45         /* Nexthop structure */
  46         struct nexthop *nexthop;
  47
  48         /* Tag */
  49         route_tag_t tag;
  50
  51         /* Uptime. */
  52         time_t uptime;
  53
  54         /* Type fo this route. */
  55         int type;
  56
  57         /* Source protocol instance */
  58         u_short instance;
  59
  60         /* VRF identifier. */
  61         vrf_id_t vrf_id;
  62
  63         /* Which routing table */
  64         uint32_t table;
  65
  66         /* Metric */
  67         u_int32_t metric;
  68
  69         /* MTU */
  70         u_int32_t mtu;
  71         u_int32_t nexthop_mtu;
  72
  73         /* Distance. */
  74         uint8_t distance;
  75
  76         /* Flags of this route.
  77          * This flag's definition is in lib/zebra.h ZEBRA_FLAG_* and is exposed
  78          * to clients via Zserv
  79          */
  80         u_int32_t flags;
  81
  82         /* RIB internal status */
  83         u_char status;
  84 #define ROUTE_ENTRY_REMOVED          0x1
  85 /* to simplify NHT logic when NHs change, instead of doing a NH by NH cmp */
  86 #define ROUTE_ENTRY_NEXTHOPS_CHANGED 0x2
  87 #define ROUTE_ENTRY_CHANGED          0x4
  88 #define ROUTE_ENTRY_SELECTED_FIB     0x8
  89 #define ROUTE_ENTRY_LABELS_CHANGED   0x10
  90
  91         /* Nexthop information. */
  92         u_char nexthop_num;
  93         u_char nexthop_active_num;
  94 };
  95
  96 /* meta-queue structure:
  97  * sub-queue 0: connected, kernel
  98  * sub-queue 1: static
  99  * sub-queue 2: RIP, RIPng, OSPF, OSPF6, IS-IS, EIGRP, NHRP
 100  * sub-queue 3: iBGP, eBGP
 101  * sub-queue 4: any other origin (if any)
 102  */
 103 #define MQ_SIZE 5
 104 struct meta_queue {
 105         struct list *subq[MQ_SIZE];
 106         u_int32_t size; /* sum of lengths of all subqueues */
 107 };
 108
 109 /*
 110  * Structure that represents a single destination (prefix).
 111  */
 112 typedef struct rib_dest_t_ {
 113
 114         /*
 115          * Back pointer to the route node for this destination. This helps
 116          * us get to the prefix that this structure is for.
 117          */
 118         struct route_node *rnode;
 119
 120         /*
 121          * Doubly-linked list of routes for this prefix.
 122          */
 123         struct route_entry *routes;
 124
 125         /*
 126          * Flags, see below.
 127          */
 128         u_int32_t flags;
 129
 130         /*
 131          * Linkage to put dest on the FPM processing queue.
 132          */
 133         TAILQ_ENTRY(rib_dest_t_) fpm_q_entries;
 134
 135 } rib_dest_t;
 136
 137 #define RIB_ROUTE_QUEUED(x)     (1 << (x))
 138 // If MQ_SIZE is modified this value needs to be updated.
 139 #define RIB_ROUTE_ANY_QUEUED    0x1F
 140
 141 /*
 142  * The maximum qindex that can be used.
 143  */
 144 #define ZEBRA_MAX_QINDEX        (MQ_SIZE - 1)
 145
 146 /*
 147  * This flag indicates that a given prefix has been 'advertised' to
 148  * the FPM to be installed in the forwarding plane.
 149  */
 150 #define RIB_DEST_SENT_TO_FPM   (1 << (ZEBRA_MAX_QINDEX + 1))
 151
 152 /*
 153  * This flag is set when we need to send an update to the FPM about a
 154  * dest.
 155  */
 156 #define RIB_DEST_UPDATE_FPM    (1 << (ZEBRA_MAX_QINDEX + 2))
 157
 158 /*
 159  * Macro to iterate over each route for a destination (prefix).
 160  */
 161 #define RE_DEST_FOREACH_ROUTE(dest, re)                                        \
 162         for ((re) = (dest) ? (dest)->routes : NULL; (re); (re) = (re)->next)
 163
 164 /*
 165  * Same as above, but allows the current node to be unlinked.
 166  */
 167 #define RE_DEST_FOREACH_ROUTE_SAFE(dest, re, next)                             \
 168         for ((re) = (dest) ? (dest)->routes : NULL;                            \
 169              (re) && ((next) = (re)->next, 1); (re) = (next))
 170
 171 #define RNODE_FOREACH_RE(rn, re)                                               \
 172         RE_DEST_FOREACH_ROUTE(rib_dest_from_rnode(rn), re)
 173
 174 #define RNODE_FOREACH_RE_SAFE(rn, re, next)                                    \
 175         RE_DEST_FOREACH_ROUTE_SAFE(rib_dest_from_rnode(rn), re, next)
 176
 177 #if defined(HAVE_RTADV)
 178 /* Structure which hold status of router advertisement. */
 179 struct rtadv {
 180         int sock;
 181
 182         int adv_if_count;
 183         int adv_msec_if_count;
 184
 185         struct thread *ra_read;
 186         struct thread *ra_timer;
 187 };
 188 #endif /* HAVE_RTADV */
 189
 190 /*
 191  * rib_table_info_t
 192  *
 193  * Structure that is hung off of a route_table that holds information about
 194  * the table.
 195  */
 196 typedef struct rib_table_info_t_ {
 197
 198         /*
 199          * Back pointer to zebra_vrf.
 200          */
 201         struct zebra_vrf *zvrf;
 202         afi_t afi;
 203         safi_t safi;
 204
 205 } rib_table_info_t;
 206
 207 typedef enum {
 208         RIB_TABLES_ITER_S_INIT,
 209         RIB_TABLES_ITER_S_ITERATING,
 210         RIB_TABLES_ITER_S_DONE
 211 } rib_tables_iter_state_t;
 212
 213 /*
 214  * Structure that holds state for iterating over all tables in the
 215  * Routing Information Base.
 216  */
 217 typedef struct rib_tables_iter_t_ {
 218         vrf_id_t vrf_id;
 219         int afi_safi_ix;
 220
 221         rib_tables_iter_state_t state;
 222 } rib_tables_iter_t;
 223
 224 /* Events/reasons triggering a RIB update. */
 225 typedef enum {
 226         RIB_UPDATE_IF_CHANGE,
 227         RIB_UPDATE_RMAP_CHANGE,
 228         RIB_UPDATE_OTHER
 229 } rib_update_event_t;
 230
 231 extern struct nexthop *route_entry_nexthop_ifindex_add(struct route_entry *,
 232                                                        ifindex_t);
 233 extern struct nexthop *route_entry_nexthop_blackhole_add(struct route_entry *,
 234                                                          enum blackhole_type);
 235 extern struct nexthop *route_entry_nexthop_ipv4_add(struct route_entry *,
 236                                                     struct in_addr *,
 237                                                     struct in_addr *);
 238 extern struct nexthop *
 239 route_entry_nexthop_ipv4_ifindex_add(struct route_entry *, struct in_addr *,
 240                                      struct in_addr *, ifindex_t);
 241 extern void route_entry_nexthop_delete(struct route_entry *re,
 242                                        struct nexthop *nexthop);
 243 extern struct nexthop *route_entry_nexthop_ipv6_add(struct route_entry *,
 244                                                     struct in6_addr *);
 245 extern struct nexthop *
 246 route_entry_nexthop_ipv6_ifindex_add(struct route_entry *re,
 247                                      struct in6_addr *ipv6, ifindex_t ifindex);
 248 extern void route_entry_nexthop_add(struct route_entry *re,
 249                                     struct nexthop *nexthop);
 250 extern void route_entry_copy_nexthops(struct route_entry *re,
 251                                       struct nexthop *nh);
 252
 253 #define route_entry_dump(prefix, src, re) _route_entry_dump(__func__, prefix, src, re)
 254 extern void _route_entry_dump(const char *, union prefixconstptr,
 255                               union prefixconstptr, const struct route_entry *);
 256 /* RPF lookup behaviour */
 257 enum multicast_mode {
 258         MCAST_NO_CONFIG = 0,  /* MIX_MRIB_FIRST, but no show in config write */
 259         MCAST_MRIB_ONLY,      /* MRIB only */
 260         MCAST_URIB_ONLY,      /* URIB only */
 261         MCAST_MIX_MRIB_FIRST, /* MRIB, if nothing at all then URIB */
 262         MCAST_MIX_DISTANCE,   /* MRIB & URIB, lower distance wins */
 263         MCAST_MIX_PFXLEN,     /* MRIB & URIB, longer prefix wins */
 264                               /* on equal value, MRIB wins for last 2 */
 265 };
 266
 267 extern void multicast_mode_ipv4_set(enum multicast_mode mode);
 268 extern enum multicast_mode multicast_mode_ipv4_get(void);
 269
 270 extern void rib_lookup_and_dump(struct prefix_ipv4 *, vrf_id_t);
 271 extern void rib_lookup_and_pushup(struct prefix_ipv4 *, vrf_id_t);
 272
 273 extern int rib_lookup_ipv4_route(struct prefix_ipv4 *, union sockunion *,
 274                                  vrf_id_t);
 275 #define ZEBRA_RIB_LOOKUP_ERROR -1
 276 #define ZEBRA_RIB_FOUND_EXACT 0
 277 #define ZEBRA_RIB_FOUND_NOGATE 1
 278 #define ZEBRA_RIB_FOUND_CONNECTED 2
 279 #define ZEBRA_RIB_NOTFOUND 3
 280
 281 extern int is_zebra_valid_kernel_table(u_int32_t table_id);
 282 extern int is_zebra_main_routing_table(u_int32_t table_id);
 283 extern int zebra_check_addr(struct prefix *p);
 284
 285 extern void rib_addnode(struct route_node *rn, struct route_entry *re,
 286                         int process);
 287 extern void rib_delnode(struct route_node *rn, struct route_entry *re);
 288 extern int rib_install_kernel(struct route_node *rn, struct route_entry *re,
 289                               struct route_entry *old);
 290 extern int rib_uninstall_kernel(struct route_node *rn, struct route_entry *re);
 291
 292 /* NOTE:
 293  * All rib_add function will not just add prefix into RIB, but
 294  * also implicitly withdraw equal prefix of same type. */
 295 extern int rib_add(afi_t afi, safi_t safi, vrf_id_t vrf_id, int type,
 296                    u_short instance, int flags, struct prefix *p,
 297                    struct prefix_ipv6 *src_p, const struct nexthop *nh,
 298                    u_int32_t table_id, u_int32_t metric, u_int32_t mtu,
 299                    uint8_t distance);
 300
 301 extern int rib_add_multipath(afi_t afi, safi_t safi, struct prefix *,
 302                              struct prefix_ipv6 *src_p, struct route_entry *);
 303
 304 extern void rib_delete(afi_t afi, safi_t safi, vrf_id_t vrf_id, int type,
 305                        u_short instance, int flags, struct prefix *p,
 306                        struct prefix_ipv6 *src_p, const struct nexthop *nh,
 307                        u_int32_t table_id, u_int32_t metric, bool fromkernel);
 308
 309 extern struct route_entry *rib_match(afi_t afi, safi_t safi, vrf_id_t,
 310                                      union g_addr *,
 311                                      struct route_node **rn_out);
 312 extern struct route_entry *rib_match_ipv4_multicast(vrf_id_t vrf_id,
 313                                                     struct in_addr addr,
 314                                                     struct route_node **rn_out);
 315
 316 extern struct route_entry *rib_lookup_ipv4(struct prefix_ipv4 *, vrf_id_t);
 317
 318 extern void rib_update(vrf_id_t, rib_update_event_t);
 319 extern void rib_weed_tables(void);
 320 extern void rib_sweep_route(void);
 321 extern void rib_close_table(struct route_table *);
 322 extern void rib_init(void);
 323 extern unsigned long rib_score_proto(u_char proto, u_short instance);
 324 extern void rib_queue_add(struct route_node *rn);
 325 extern void meta_queue_free(struct meta_queue *mq);
 326 extern int zebra_rib_labeled_unicast(struct route_entry *re);
 327 extern struct route_table *rib_table_ipv6;
 328
 329 extern void rib_unlink(struct route_node *, struct route_entry *);
 330 extern int rib_gc_dest(struct route_node *rn);
 331 extern struct route_table *rib_tables_iter_next(rib_tables_iter_t *iter);
 332
 333 extern uint8_t route_distance(int type);
 334
 335 /*
 336  * Inline functions.
 337  */
 338
 339 /*
 340  * rib_table_info
 341  */
 342 static inline rib_table_info_t *rib_table_info(struct route_table *table)
 343 {
 344         return (rib_table_info_t *)table->info;
 345 }
 346
 347 /*
 348  * rib_dest_from_rnode
 349  */
 350 static inline rib_dest_t *rib_dest_from_rnode(struct route_node *rn)
 351 {
 352         return (rib_dest_t *)rn->info;
 353 }
 354
 355 /*
 356  * rnode_to_ribs
 357  *
 358  * Returns a pointer to the list of routes corresponding to the given
 359  * route_node.
 360  */
 361 static inline struct route_entry *rnode_to_ribs(struct route_node *rn)
 362 {
 363         rib_dest_t *dest;
 364
 365         dest = rib_dest_from_rnode(rn);
 366         if (!dest)
 367                 return NULL;
 368
 369         return dest->routes;
 370 }
 371
 372 /*
 373  * rib_dest_prefix
 374  */
 375 static inline struct prefix *rib_dest_prefix(rib_dest_t *dest)
 376 {
 377         return &dest->rnode->p;
 378 }
 379
 380 /*
 381  * rib_dest_af
 382  *
 383  * Returns the address family that the destination is for.
 384  */
 385 static inline u_char rib_dest_af(rib_dest_t *dest)
 386 {
 387         return dest->rnode->p.family;
 388 }
 389
 390 /*
 391  * rib_dest_table
 392  */
 393 static inline struct route_table *rib_dest_table(rib_dest_t *dest)
 394 {
 395         return srcdest_rnode_table(dest->rnode);
 396 }
 397
 398 /*
 399  * rib_dest_vrf
 400  */
 401 static inline struct zebra_vrf *rib_dest_vrf(rib_dest_t *dest)
 402 {
 403         return rib_table_info(rib_dest_table(dest))->zvrf;
 404 }
 405
 406 /*
 407  * rib_tables_iter_init
 408  */
 409 static inline void rib_tables_iter_init(rib_tables_iter_t *iter)
 410
 411 {
 412         memset(iter, 0, sizeof(*iter));
 413         iter->state = RIB_TABLES_ITER_S_INIT;
 414 }
 415
 416 /*
 417  * rib_tables_iter_started
 418  *
 419  * Returns TRUE if this iterator has started iterating over the set of
 420  * tables.
 421  */
 422 static inline int rib_tables_iter_started(rib_tables_iter_t *iter)
 423 {
 424         return iter->state != RIB_TABLES_ITER_S_INIT;
 425 }
 426
 427 /*
 428  * rib_tables_iter_cleanup
 429  */
 430 static inline void rib_tables_iter_cleanup(rib_tables_iter_t *iter)
 431 {
 432         iter->state = RIB_TABLES_ITER_S_DONE;
 433 }
 434
 435 DECLARE_HOOK(rib_update, (struct route_node * rn, const char *reason),
 436              (rn, reason))
 437
 438 #endif /*_ZEBRA_RIB_H */