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         /* Refrence count. */
  49         unsigned long refcnt;
  50
  51         /* Tag */
  52         route_tag_t tag;
  53
  54         /* Uptime. */
  55         time_t uptime;
  56
  57         /* Type fo this route. */
  58         int type;
  59
  60         /* Source protocol instance */
  61         u_short instance;
  62
  63         /* VRF identifier. */
  64         vrf_id_t vrf_id;
  65
  66         /* Which routing table */
  67         uint32_t table;
  68
  69         /* Metric */
  70         u_int32_t metric;
  71
  72         /* MTU */
  73         u_int32_t mtu;
  74         u_int32_t nexthop_mtu;
  75
  76         /* Distance. */
  77         u_char distance;
  78
  79         /* Flags of this route.
  80          * This flag's definition is in lib/zebra.h ZEBRA_FLAG_* and is exposed
  81          * to clients via Zserv
  82          */
  83         u_int32_t flags;
  84
  85         /* RIB internal status */
  86         u_char status;
  87 #define ROUTE_ENTRY_REMOVED          0x1
  88 /* to simplify NHT logic when NHs change, instead of doing a NH by NH cmp */
  89 #define ROUTE_ENTRY_NEXTHOPS_CHANGED 0x2
  90 #define ROUTE_ENTRY_CHANGED          0x4
  91 #define ROUTE_ENTRY_SELECTED_FIB     0x8
  92
  93         /* Nexthop information. */
  94         u_char nexthop_num;
  95         u_char nexthop_active_num;
  96 };
  97
  98 /* meta-queue structure:
  99  * sub-queue 0: connected, kernel
 100  * sub-queue 1: static
 101  * sub-queue 2: RIP, RIPng, OSPF, OSPF6, IS-IS, EIGRP, NHRP
 102  * sub-queue 3: iBGP, eBGP
 103  * sub-queue 4: any other origin (if any)
 104  */
 105 #define MQ_SIZE 5
 106 struct meta_queue {
 107         struct list *subq[MQ_SIZE];
 108         u_int32_t size; /* sum of lengths of all subqueues */
 109 };
 110
 111 /*
 112  * Structure that represents a single destination (prefix).
 113  */
 114 typedef struct rib_dest_t_ {
 115
 116         /*
 117          * Back pointer to the route node for this destination. This helps
 118          * us get to the prefix that this structure is for.
 119          */
 120         struct route_node *rnode;
 121
 122         /*
 123          * Doubly-linked list of routes for this prefix.
 124          */
 125         struct route_entry *routes;
 126
 127         /*
 128          * Flags, see below.
 129          */
 130         u_int32_t flags;
 131
 132         /*
 133          * Linkage to put dest on the FPM processing queue.
 134          */
 135         TAILQ_ENTRY(rib_dest_t_) fpm_q_entries;
 136
 137 } rib_dest_t;
 138
 139 #define RIB_ROUTE_QUEUED(x)     (1 << (x))
 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 extern struct nexthop *route_entry_nexthop_ipv4_add(struct route_entry *,
 235                                                     struct in_addr *,
 236                                                     struct in_addr *);
 237 extern struct nexthop *
 238 route_entry_nexthop_ipv4_ifindex_add(struct route_entry *, struct in_addr *,
 239                                      struct in_addr *, ifindex_t);
 240 extern void route_entry_nexthop_delete(struct route_entry *re,
 241                                        struct nexthop *nexthop);
 242 extern struct nexthop *route_entry_nexthop_ipv6_add(struct route_entry *,
 243                                                     struct in6_addr *);
 244 extern struct nexthop *
 245 route_entry_nexthop_ipv6_ifindex_add(struct route_entry *re,
 246                                      struct in6_addr *ipv6, ifindex_t ifindex);
 247 extern void route_entry_nexthop_add(struct route_entry *re,
 248                                     struct nexthop *nexthop);
 249 extern void route_entry_copy_nexthops(struct route_entry *re,
 250                                       struct nexthop *nh);
 251
 252 #define route_entry_dump(prefix, src, re) _route_entry_dump(__func__, prefix, src, re)
 253 extern void _route_entry_dump(const char *, union prefixconstptr,
 254                               union prefixconstptr, const struct route_entry *);
 255 /* RPF lookup behaviour */
 256 enum multicast_mode {
 257         MCAST_NO_CONFIG = 0,  /* MIX_MRIB_FIRST, but no show in config write */
 258         MCAST_MRIB_ONLY,      /* MRIB only */
 259         MCAST_URIB_ONLY,      /* URIB only */
 260         MCAST_MIX_MRIB_FIRST, /* MRIB, if nothing at all then URIB */
 261         MCAST_MIX_DISTANCE,   /* MRIB & URIB, lower distance wins */
 262         MCAST_MIX_PFXLEN,     /* MRIB & URIB, longer prefix wins */
 263                               /* on equal value, MRIB wins for last 2 */
 264 };
 265
 266 extern void multicast_mode_ipv4_set(enum multicast_mode mode);
 267 extern enum multicast_mode multicast_mode_ipv4_get(void);
 268
 269 extern void rib_lookup_and_dump(struct prefix_ipv4 *, vrf_id_t);
 270 extern void rib_lookup_and_pushup(struct prefix_ipv4 *, vrf_id_t);
 271
 272 extern int rib_lookup_ipv4_route(struct prefix_ipv4 *, union sockunion *,
 273                                  vrf_id_t);
 274 #define ZEBRA_RIB_LOOKUP_ERROR -1
 275 #define ZEBRA_RIB_FOUND_EXACT 0
 276 #define ZEBRA_RIB_FOUND_NOGATE 1
 277 #define ZEBRA_RIB_FOUND_CONNECTED 2
 278 #define ZEBRA_RIB_NOTFOUND 3
 279
 280 extern int is_zebra_valid_kernel_table(u_int32_t table_id);
 281 extern int is_zebra_main_routing_table(u_int32_t table_id);
 282 extern int zebra_check_addr(struct prefix *p);
 283
 284 extern void rib_addnode(struct route_node *rn, struct route_entry *re,
 285                         int process);
 286 extern void rib_delnode(struct route_node *rn, struct route_entry *re);
 287 extern int rib_install_kernel(struct route_node *rn, struct route_entry *re,
 288                               struct route_entry *old);
 289 extern int rib_uninstall_kernel(struct route_node *rn, struct route_entry *re);
 290
 291 /* NOTE:
 292  * All rib_add function will not just add prefix into RIB, but
 293  * also implicitly withdraw equal prefix of same type. */
 294 extern int rib_add(afi_t afi, safi_t safi, vrf_id_t vrf_id, int type,
 295                    u_short instance, int flags, struct prefix *p,
 296                    struct prefix_ipv6 *src_p, union g_addr *gate,
 297                    union g_addr *src, ifindex_t ifindex, u_int32_t table_id,
 298                    u_int32_t, u_int32_t, u_char);
 299
 300 extern int rib_add_multipath(afi_t afi, safi_t safi, struct prefix *,
 301                              struct prefix_ipv6 *src_p, struct route_entry *);
 302
 303 extern void rib_delete(afi_t afi, safi_t safi, vrf_id_t vrf_id, int type,
 304                        u_short instance, int flags, struct prefix *p,
 305                        struct prefix_ipv6 *src_p, union g_addr *gate,
 306                        ifindex_t ifindex, u_int32_t table_id);
 307
 308 extern struct route_entry *rib_match(afi_t afi, safi_t safi, vrf_id_t,
 309                                      union g_addr *,
 310                                      struct route_node **rn_out);
 311 extern struct route_entry *rib_match_ipv4_multicast(vrf_id_t vrf_id,
 312                                                     struct in_addr addr,
 313                                                     struct route_node **rn_out);
 314
 315 extern struct route_entry *rib_lookup_ipv4(struct prefix_ipv4 *, vrf_id_t);
 316
 317 extern void rib_update(vrf_id_t, rib_update_event_t);
 318 extern void rib_weed_tables(void);
 319 extern void rib_sweep_route(void);
 320 extern void rib_close_table(struct route_table *);
 321 extern void rib_init(void);
 322 extern unsigned long rib_score_proto(u_char proto, u_short instance);
 323 extern void rib_queue_add(struct route_node *rn);
 324 extern void meta_queue_free(struct meta_queue *mq);
 325 extern int zebra_rib_labeled_unicast(struct route_entry *re);
 326 extern struct route_table *rib_table_ipv6;
 327
 328 extern void rib_unlink(struct route_node *, struct route_entry *);
 329 extern int rib_gc_dest(struct route_node *rn);
 330 extern struct route_table *rib_tables_iter_next(rib_tables_iter_t *iter);
 331
 332 extern u_char route_distance(int type);
 333
 334 /*
 335  * Inline functions.
 336  */
 337
 338 /*
 339  * rib_table_info
 340  */
 341 static inline rib_table_info_t *rib_table_info(struct route_table *table)
 342 {
 343         return (rib_table_info_t *)table->info;
 344 }
 345
 346 /*
 347  * rib_dest_from_rnode
 348  */
 349 static inline rib_dest_t *rib_dest_from_rnode(struct route_node *rn)
 350 {
 351         return (rib_dest_t *)rn->info;
 352 }
 353
 354 /*
 355  * rnode_to_ribs
 356  *
 357  * Returns a pointer to the list of routes corresponding to the given
 358  * route_node.
 359  */
 360 static inline struct route_entry *rnode_to_ribs(struct route_node *rn)
 361 {
 362         rib_dest_t *dest;
 363
 364         dest = rib_dest_from_rnode(rn);
 365         if (!dest)
 366                 return NULL;
 367
 368         return dest->routes;
 369 }
 370
 371 /*
 372  * rib_dest_prefix
 373  */
 374 static inline struct prefix *rib_dest_prefix(rib_dest_t *dest)
 375 {
 376         return &dest->rnode->p;
 377 }
 378
 379 /*
 380  * rib_dest_af
 381  *
 382  * Returns the address family that the destination is for.
 383  */
 384 static inline u_char rib_dest_af(rib_dest_t *dest)
 385 {
 386         return dest->rnode->p.family;
 387 }
 388
 389 /*
 390  * rib_dest_table
 391  */
 392 static inline struct route_table *rib_dest_table(rib_dest_t *dest)
 393 {
 394         return srcdest_rnode_table(dest->rnode);
 395 }
 396
 397 /*
 398  * rib_dest_vrf
 399  */
 400 static inline struct zebra_vrf *rib_dest_vrf(rib_dest_t *dest)
 401 {
 402         return rib_table_info(rib_dest_table(dest))->zvrf;
 403 }
 404
 405 /*
 406  * rib_tables_iter_init
 407  */
 408 static inline void rib_tables_iter_init(rib_tables_iter_t *iter)
 409
 410 {
 411         memset(iter, 0, sizeof(*iter));
 412         iter->state = RIB_TABLES_ITER_S_INIT;
 413 }
 414
 415 /*
 416  * rib_tables_iter_started
 417  *
 418  * Returns TRUE if this iterator has started iterating over the set of
 419  * tables.
 420  */
 421 static inline int rib_tables_iter_started(rib_tables_iter_t *iter)
 422 {
 423         return iter->state != RIB_TABLES_ITER_S_INIT;
 424 }
 425
 426 /*
 427  * rib_tables_iter_cleanup
 428  */
 429 static inline void rib_tables_iter_cleanup(rib_tables_iter_t *iter)
 430 {
 431         iter->state = RIB_TABLES_ITER_S_DONE;
 432 }
 433
 434 DECLARE_HOOK(rib_update, (struct route_node * rn, const char *reason),
 435              (rn, reason))
 436
 437 #endif /*_ZEBRA_RIB_H */