nest/route.h

   1 /*
   2  *      BIRD Internet Routing Daemon -- Routing Table
   3  *
   4  *      (c) 1998--2000 Martin Mares <mj@ucw.cz>
   5  *
   6  *      Can be freely distributed and used under the terms of the GNU GPL.
   7  */
   8
   9 #ifndef _BIRD_ROUTE_H_
  10 #define _BIRD_ROUTE_H_
  11
  12 #include "lib/lists.h"
  13 #include "lib/resource.h"
  14 #include "lib/net.h"
  15
  16 struct ea_list;
  17 struct protocol;
  18 struct proto;
  19 struct rte_src;
  20 struct symbol;
  21 struct filter;
  22 struct cli;
  23
  24 /*
  25  *      Generic data structure for storing network prefixes. Also used
  26  *      for the master routing table. Currently implemented as a hash
  27  *      table.
  28  *
  29  *      Available operations:
  30  *              - insertion of new entry
  31  *              - deletion of entry
  32  *              - searching for entry by network prefix
  33  *              - asynchronous retrieval of fib contents
  34  */
  35
  36 struct fib_node {
  37   struct fib_node *next;                /* Next in hash chain */
  38   struct fib_iterator *readers;         /* List of readers of this node */
  39   byte flags;                           /* User-defined, will be removed */
  40   net_addr addr[0];
  41 };
  42
  43 struct fib_iterator {                   /* See lib/slists.h for an explanation */
  44   struct fib_iterator *prev, *next;     /* Must be synced with struct fib_node! */
  45   byte efef;                            /* 0xff to distinguish between iterator and node */
  46   byte pad[3];
  47   struct fib_node *node;                /* Or NULL if freshly merged */
  48   uint hash;
  49 };
  50
  51 typedef void (*fib_init_fn)(void *);
  52
  53 struct fib {
  54   pool *fib_pool;                       /* Pool holding all our data */
  55   slab *fib_slab;                       /* Slab holding all fib nodes */
  56   struct fib_node **hash_table;         /* Node hash table */
  57   uint hash_size;                       /* Number of hash table entries (a power of two) */
  58   uint hash_order;                      /* Binary logarithm of hash_size */
  59   uint hash_shift;                      /* 32 - hash_order */
  60   uint addr_type;                       /* Type of address data stored in fib (NET_*) */
  61   uint node_size;                       /* FIB node size, 0 for nonuniform */
  62   uint node_offset;                     /* Offset of fib_node struct inside of user data */
  63   uint entries;                         /* Number of entries */
  64   uint entries_min, entries_max;        /* Entry count limits (else start rehashing) */
  65   fib_init_fn init;                     /* Constructor */
  66 };
  67
  68 static inline void * fib_node_to_user(struct fib *f, struct fib_node *e)
  69 { return e ? (void *) ((char *) e - f->node_offset) : NULL; }
  70
  71 static inline struct fib_node * fib_user_to_node(struct fib *f, void *e)
  72 { return e ? (void *) ((char *) e + f->node_offset) : NULL; }
  73
  74 void fib_init(struct fib *f, pool *p, uint addr_type, uint node_size, uint node_offset, uint hash_order, fib_init_fn init);
  75 void *fib_find(struct fib *, const net_addr *); /* Find or return NULL if doesn't exist */
  76 void *fib_get_chain(struct fib *f, const net_addr *a); /* Find first node in linked list from hash table */
  77 void *fib_get(struct fib *, const net_addr *);  /* Find or create new if nonexistent */
  78 void *fib_route(struct fib *, const net_addr *); /* Longest-match routing lookup */
  79 void fib_delete(struct fib *, void *);  /* Remove fib entry */
  80 void fib_free(struct fib *);            /* Destroy the fib */
  81 void fib_check(struct fib *);           /* Consistency check for debugging */
  82
  83 void fit_init(struct fib_iterator *, struct fib *); /* Internal functions, don't call */
  84 struct fib_node *fit_get(struct fib *, struct fib_iterator *);
  85 void fit_put(struct fib_iterator *, struct fib_node *);
  86 void fit_put_next(struct fib *f, struct fib_iterator *i, struct fib_node *n, uint hpos);
  87
  88
  89 #define FIB_WALK(fib, type, z) do {                             \
  90         struct fib_node *fn_, **ff_ = (fib)->hash_table;        \
  91         uint count_ = (fib)->hash_size;                         \
  92         type *z;                                                \
  93         while (count_--)                                        \
  94           for (fn_ = *ff_++; z = fib_node_to_user(fib, fn_); fn_=fn_->next)
  95
  96 #define FIB_WALK_END } while (0)
  97
  98 #define FIB_ITERATE_INIT(it, fib) fit_init(it, fib)
  99
 100 #define FIB_ITERATE_START(fib, it, type, z) do {                \
 101         struct fib_node *fn_ = fit_get(fib, it);                \
 102         uint count_ = (fib)->hash_size;                         \
 103         uint hpos_ = (it)->hash;                                \
 104         type *z;                                                \
 105         for(;;) {                                               \
 106           if (!fn_)                                             \
 107             {                                                   \
 108                if (++hpos_ >= count_)                           \
 109                  break;                                         \
 110                fn_ = (fib)->hash_table[hpos_];                  \
 111                continue;                                        \
 112             }                                                   \
 113           z = fib_node_to_user(fib, fn_);
 114
 115 #define FIB_ITERATE_END fn_ = fn_->next; } } while(0)
 116
 117 #define FIB_ITERATE_PUT(it) fit_put(it, fn_)
 118
 119 #define FIB_ITERATE_PUT_NEXT(it, fib) fit_put_next(fib, it, fn_, hpos_)
 120
 121 #define FIB_ITERATE_UNLINK(it, fib) fit_get(fib, it)
 122
 123
 124 /*
 125  *      Master Routing Tables. Generally speaking, each of them contains a FIB
 126  *      with each entry pointing to a list of route entries representing routes
 127  *      to given network (with the selected one at the head).
 128  *
 129  *      Each of the RTE's contains variable data (the preference and protocol-dependent
 130  *      metrics) and a pointer to a route attribute block common for many routes).
 131  *
 132  *      It's guaranteed that there is at most one RTE for every (prefix,proto) pair.
 133  */
 134
 135 struct rtable_config {
 136   node n;
 137   char *name;
 138   struct rtable *table;
 139   struct proto_config *krt_attached;    /* Kernel syncer attached to this table */
 140   uint addr_type;                       /* Type of address data stored in table (NET_*) */
 141   int gc_max_ops;                       /* Maximum number of operations before GC is run */
 142   int gc_min_time;                      /* Minimum time between two consecutive GC runs */
 143   byte sorted;                          /* Routes of network are sorted according to rte_better() */
 144 };
 145
 146 typedef struct rtable {
 147   node n;                               /* Node in list of all tables */
 148   struct fib fib;
 149   char *name;                           /* Name of this table */
 150   list channels;                        /* List of attached channels (struct channel) */
 151   uint addr_type;                       /* Type of address data stored in table (NET_*) */
 152   int pipe_busy;                        /* Pipe loop detection */
 153   int use_count;                        /* Number of protocols using this table */
 154   u32 rt_count;                         /* Number of routes in the table */
 155   struct hostcache *hostcache;
 156   struct rtable_config *config;         /* Configuration of this table */
 157   struct config *deleted;               /* Table doesn't exist in current configuration,
 158                                          * delete as soon as use_count becomes 0 and remove
 159                                          * obstacle from this routing table.
 160                                          */
 161   struct event *rt_event;               /* Routing table event */
 162   btime gc_time;                        /* Time of last GC */
 163   int gc_counter;                       /* Number of operations since last GC */
 164   byte prune_state;                     /* Table prune state, 1 -> scheduled, 2-> running */
 165   byte hcu_scheduled;                   /* Hostcache update is scheduled */
 166   byte nhu_state;                       /* Next Hop Update state */
 167   struct fib_iterator prune_fit;        /* Rtable prune FIB iterator */
 168   struct fib_iterator nhu_fit;          /* Next Hop Update FIB iterator */
 169 } rtable;
 170
 171 #define NHU_CLEAN       0
 172 #define NHU_SCHEDULED   1
 173 #define NHU_RUNNING     2
 174 #define NHU_DIRTY       3
 175
 176 typedef struct network {
 177   struct rte *routes;                   /* Available routes for this network */
 178   struct fib_node n;                    /* FIB flags reserved for kernel syncer */
 179 } net;
 180
 181 struct hostcache {
 182   slab *slab;                           /* Slab holding all hostentries */
 183   struct hostentry **hash_table;        /* Hash table for hostentries */
 184   unsigned hash_order, hash_shift;
 185   unsigned hash_max, hash_min;
 186   unsigned hash_items;
 187   linpool *lp;                          /* Linpool for trie */
 188   struct f_trie *trie;                  /* Trie of prefixes that might affect hostentries */
 189   list hostentries;                     /* List of all hostentries */
 190   byte update_hostcache;
 191 };
 192
 193 struct hostentry {
 194   node ln;
 195   ip_addr addr;                         /* IP address of host, part of key */
 196   ip_addr link;                         /* (link-local) IP address of host, used as gw
 197                                            if host is directly attached */
 198   struct rtable *tab;                   /* Dependent table, part of key */
 199   struct hostentry *next;               /* Next in hash chain */
 200   unsigned hash_key;                    /* Hash key */
 201   unsigned uc;                          /* Use count */
 202   struct rta *src;                      /* Source rta entry */
 203   byte dest;                            /* Chosen route destination type (RTD_...) */
 204   byte nexthop_linkable;                /* Nexthop list is completely non-device */
 205   u32 igp_metric;                       /* Chosen route IGP metric */
 206 };
 207
 208 typedef struct rte {
 209   struct rte *next;
 210   net *net;                             /* Network this RTE belongs to */
 211   struct channel *sender;               /* Channel used to send the route to the routing table */
 212   struct rta *attrs;                    /* Attributes of this route */
 213   byte flags;                           /* Flags (REF_...) */
 214   byte pflags;                          /* Protocol-specific flags */
 215   word pref;                            /* Route preference */
 216   btime lastmod;                        /* Last modified */
 217   union {                               /* Protocol-dependent data (metrics etc.) */
 218 #ifdef CONFIG_RIP
 219     struct {
 220       struct iface *from;               /* Incoming iface */
 221       u8 metric;                        /* RIP metric */
 222       u16 tag;                          /* External route tag */
 223     } rip;
 224 #endif
 225 #ifdef CONFIG_OSPF
 226     struct {
 227       u32 metric1, metric2;             /* OSPF Type 1 and Type 2 metrics */
 228       u32 tag;                          /* External route tag */
 229       u32 router_id;                    /* Router that originated this route */
 230     } ospf;
 231 #endif
 232 #ifdef CONFIG_BGP
 233     struct {
 234       u8 suppressed;                    /* Used for deterministic MED comparison */
 235       s8 stale;                         /* Route is LLGR_STALE, -1 if unknown */
 236     } bgp;
 237 #endif
 238 #ifdef CONFIG_BABEL
 239     struct {
 240       u16 seqno;                        /* Babel seqno */
 241       u16 metric;                       /* Babel metric */
 242       u64 router_id;                    /* Babel router id */
 243     } babel;
 244 #endif
 245     struct {                            /* Routes generated by krt sync (both temporary and inherited ones) */
 246       s8 src;                           /* Alleged route source (see krt.h) */
 247       u8 proto;                         /* Kernel source protocol ID */
 248       u8 seen;                          /* Seen during last scan */
 249       u8 best;                          /* Best route in network, propagated to core */
 250       u32 metric;                       /* Kernel metric */
 251     } krt;
 252   } u;
 253 } rte;
 254
 255 #define REF_COW         1               /* Copy this rte on write */
 256 #define REF_FILTERED    2               /* Route is rejected by import filter */
 257 #define REF_STALE       4               /* Route is stale in a refresh cycle */
 258 #define REF_DISCARD     8               /* Route is scheduled for discard */
 259 #define REF_MODIFY      16              /* Route is scheduled for modify */
 260
 261 /* Route is valid for propagation (may depend on other flags in the future), accepts NULL */
 262 static inline int rte_is_valid(rte *r) { return r && !(r->flags & REF_FILTERED); }
 263
 264 /* Route just has REF_FILTERED flag */
 265 static inline int rte_is_filtered(rte *r) { return !!(r->flags & REF_FILTERED); }
 266
 267
 268 /* Types of route announcement, also used as flags */
 269 #define RA_UNDEF        0               /* Undefined RA type */
 270 #define RA_OPTIMAL      1               /* Announcement of optimal route change */
 271 #define RA_ACCEPTED     2               /* Announcement of first accepted route */
 272 #define RA_ANY          3               /* Announcement of any route change */
 273 #define RA_MERGED       4               /* Announcement of optimal route merged with next ones */
 274
 275 /* Return value of preexport() callback */
 276 #define RIC_ACCEPT      1               /* Accepted by protocol */
 277 #define RIC_PROCESS     0               /* Process it through import filter */
 278 #define RIC_REJECT      -1              /* Rejected by protocol */
 279 #define RIC_DROP        -2              /* Silently dropped by protocol */
 280
 281 extern list routing_tables;
 282 struct config;
 283
 284 void rt_init(void);
 285 void rt_preconfig(struct config *);
 286 void rt_commit(struct config *new, struct config *old);
 287 void rt_lock_table(rtable *);
 288 void rt_unlock_table(rtable *);
 289 void rt_setup(pool *, rtable *, struct rtable_config *);
 290 static inline net *net_find(rtable *tab, const net_addr *addr) { return (net *) fib_find(&tab->fib, addr); }
 291 static inline net *net_find_valid(rtable *tab, const net_addr *addr)
 292 { net *n = net_find(tab, addr); return (n && rte_is_valid(n->routes)) ? n : NULL; }
 293 static inline net *net_get(rtable *tab, const net_addr *addr) { return (net *) fib_get(&tab->fib, addr); }
 294 void *net_route(rtable *tab, const net_addr *n);
 295 int net_roa_check(rtable *tab, const net_addr *n, u32 asn);
 296 rte *rte_find(net *net, struct rte_src *src);
 297 rte *rte_get_temp(struct rta *);
 298 void rte_update2(struct channel *c, const net_addr *n, rte *new, struct rte_src *src);
 299 /* rte_update() moved to protocol.h to avoid dependency conflicts */
 300 int rt_examine(rtable *t, net_addr *a, struct proto *p, struct filter *filter);
 301 rte *rt_export_merged(struct channel *c, net *net, rte **rt_free, linpool *pool, int silent);
 302 void rt_refresh_begin(rtable *t, struct channel *c);
 303 void rt_refresh_end(rtable *t, struct channel *c);
 304 void rt_modify_stale(rtable *t, struct channel *c);
 305 void rt_schedule_prune(rtable *t);
 306 void rte_dump(rte *);
 307 void rte_free(rte *);
 308 rte *rte_do_cow(rte *);
 309 static inline rte * rte_cow(rte *r) { return (r->flags & REF_COW) ? rte_do_cow(r) : r; }
 310 rte *rte_cow_rta(rte *r, linpool *lp);
 311 void rte_init_tmp_attrs(struct rte *r, linpool *lp, uint max);
 312 void rte_make_tmp_attr(struct rte *r, uint id, uint type, uintptr_t val);
 313 void rte_make_tmp_attrs(struct rte **r, struct linpool *pool, struct rta **old_attrs);
 314 uintptr_t rte_store_tmp_attr(struct rte *r, uint id);
 315 void rt_dump(rtable *);
 316 void rt_dump_all(void);
 317 int rt_feed_channel(struct channel *c);
 318 void rt_feed_channel_abort(struct channel *c);
 319 int rte_update_in(struct channel *c, const net_addr *n, rte *new, struct rte_src *src);
 320 int rt_reload_channel(struct channel *c);
 321 void rt_reload_channel_abort(struct channel *c);
 322 void rt_prune_sync(rtable *t, int all);
 323 struct rtable_config *rt_new_table(struct symbol *s, uint addr_type);
 324
 325
 326 /* Default limit for ECMP next hops, defined in sysdep code */
 327 extern const int rt_default_ecmp;
 328
 329 struct rt_show_data_rtable {
 330   node n;
 331   rtable *table;
 332   struct channel *export_channel;
 333 };
 334
 335 struct rt_show_data {
 336   net_addr *addr;
 337   list tables;
 338   struct rt_show_data_rtable *tab;      /* Iterator over table list */
 339   struct rt_show_data_rtable *last_table; /* Last table in output */
 340   struct fib_iterator fit;              /* Iterator over networks in table */
 341   int verbose, tables_defined_by;
 342   struct filter *filter;
 343   struct proto *show_protocol;
 344   struct proto *export_protocol;
 345   struct channel *export_channel;
 346   struct config *running_on_config;
 347   int export_mode, primary_only, filtered, stats, show_for;
 348
 349   int table_open;                       /* Iteration (fit) is open */
 350   int net_counter, rt_counter, show_counter, table_counter;
 351   int net_counter_last, rt_counter_last, show_counter_last;
 352 };
 353
 354 void rt_show(struct rt_show_data *);
 355 struct rt_show_data_rtable * rt_show_add_table(struct rt_show_data *d, rtable *t);
 356
 357 /* Value of table definition mode in struct rt_show_data */
 358 #define RSD_TDB_DEFAULT   0             /* no table specified */
 359 #define RSD_TDB_INDIRECT  0             /* show route ... protocol P ... */
 360 #define RSD_TDB_ALL       RSD_TDB_SET                   /* show route ... table all ... */
 361 #define RSD_TDB_DIRECT    RSD_TDB_SET | RSD_TDB_NMN     /* show route ... table X table Y ... */
 362
 363 #define RSD_TDB_SET       0x1           /* internal: show empty tables */
 364 #define RSD_TDB_NMN       0x2           /* internal: need matching net */
 365
 366 /* Value of export_mode in struct rt_show_data */
 367 #define RSEM_NONE       0               /* Export mode not used */
 368 #define RSEM_PREEXPORT  1               /* Routes ready for export, before filtering */
 369 #define RSEM_EXPORT     2               /* Routes accepted by export filter */
 370 #define RSEM_NOEXPORT   3               /* Routes rejected by export filter */
 371
 372 /*
 373  *      Route Attributes
 374  *
 375  *      Beware: All standard BGP attributes must be represented here instead
 376  *      of making them local to the route. This is needed to ensure proper
 377  *      construction of BGP route attribute lists.
 378  */
 379
 380 /* Nexthop structure */
 381 struct nexthop {
 382   ip_addr gw;                           /* Next hop */
 383   struct iface *iface;                  /* Outgoing interface */
 384   struct nexthop *next;
 385   byte flags;
 386   byte weight;
 387   byte labels_orig;                     /* Number of labels before hostentry was applied */
 388   byte labels;                          /* Number of all labels */
 389   u32 label[0];
 390 };
 391
 392 #define RNF_ONLINK              0x1     /* Gateway is onlink regardless of IP ranges */
 393
 394
 395 struct rte_src {
 396   struct rte_src *next;                 /* Hash chain */
 397   struct proto *proto;                  /* Protocol the source is based on */
 398   u32 private_id;                       /* Private ID, assigned by the protocol */
 399   u32 global_id;                        /* Globally unique ID of the source */
 400   unsigned uc;                          /* Use count */
 401 };
 402
 403
 404 typedef struct rta {
 405   struct rta *next, **pprev;            /* Hash chain */
 406   u32 uc;                               /* Use count */
 407   u32 hash_key;                         /* Hash over important fields */
 408   struct ea_list *eattrs;               /* Extended Attribute chain */
 409   struct rte_src *src;                  /* Route source that created the route */
 410   struct hostentry *hostentry;          /* Hostentry for recursive next-hops */
 411   ip_addr from;                         /* Advertising router */
 412   u32 igp_metric;                       /* IGP metric to next hop (for iBGP routes) */
 413   u8 source;                            /* Route source (RTS_...) */
 414   u8 scope;                             /* Route scope (SCOPE_... -- see ip.h) */
 415   u8 dest;                              /* Route destination type (RTD_...) */
 416   u8 aflags;
 417   struct nexthop nh;                    /* Next hop */
 418 } rta;
 419
 420 #define RTS_DUMMY 0                     /* Dummy route to be removed soon */
 421 #define RTS_STATIC 1                    /* Normal static route */
 422 #define RTS_INHERIT 2                   /* Route inherited from kernel */
 423 #define RTS_DEVICE 3                    /* Device route */
 424 #define RTS_STATIC_DEVICE 4             /* Static device route */
 425 #define RTS_REDIRECT 5                  /* Learned via redirect */
 426 #define RTS_RIP 6                       /* RIP route */
 427 #define RTS_OSPF 7                      /* OSPF route */
 428 #define RTS_OSPF_IA 8                   /* OSPF inter-area route */
 429 #define RTS_OSPF_EXT1 9                 /* OSPF external route type 1 */
 430 #define RTS_OSPF_EXT2 10                /* OSPF external route type 2 */
 431 #define RTS_BGP 11                      /* BGP route */
 432 #define RTS_PIPE 12                     /* Inter-table wormhole */
 433 #define RTS_BABEL 13                    /* Babel route */
 434 #define RTS_RPKI 14                     /* Route Origin Authorization */
 435 #define RTS_PERF 15                     /* Perf checker */
 436 #define RTS_MAX 16
 437
 438 #define RTC_UNICAST 0
 439 #define RTC_BROADCAST 1
 440 #define RTC_MULTICAST 2
 441 #define RTC_ANYCAST 3                   /* IPv6 Anycast */
 442
 443 #define RTD_NONE 0                      /* Undefined next hop */
 444 #define RTD_UNICAST 1                   /* Next hop is neighbor router */
 445 #define RTD_BLACKHOLE 2                 /* Silently drop packets */
 446 #define RTD_UNREACHABLE 3               /* Reject as unreachable */
 447 #define RTD_PROHIBIT 4                  /* Administratively prohibited */
 448 #define RTD_MAX 5
 449
 450                                         /* Flags for net->n.flags, used by kernel syncer */
 451 #define KRF_INSTALLED 0x80              /* This route should be installed in the kernel */
 452 #define KRF_SYNC_ERROR 0x40             /* Error during kernel table synchronization */
 453
 454 #define RTAF_CACHED 1                   /* This is a cached rta */
 455
 456 #define IGP_METRIC_UNKNOWN 0x80000000   /* Default igp_metric used when no other
 457                                            protocol-specific metric is availabe */
 458
 459
 460 const char * rta_dest_names[RTD_MAX];
 461
 462 static inline const char *rta_dest_name(uint n)
 463 { return (n < RTD_MAX) ? rta_dest_names[n] : "???"; }
 464
 465 /* Route has regular, reachable nexthop (i.e. not RTD_UNREACHABLE and like) */
 466 static inline int rte_is_reachable(rte *r)
 467 { return r->attrs->dest == RTD_UNICAST; }
 468
 469
 470 /*
 471  *      Extended Route Attributes
 472  */
 473
 474 typedef struct eattr {
 475   word id;                              /* EA_CODE(PROTOCOL_..., protocol-dependent ID) */
 476   byte flags;                           /* Protocol-dependent flags */
 477   byte type;                            /* Attribute type and several flags (EAF_...) */
 478   union {
 479     u32 data;
 480     struct adata *ptr;                  /* Attribute data elsewhere */
 481   } u;
 482 } eattr;
 483
 484
 485 #define EA_CODE(proto,id) (((proto) << 8) | (id))
 486 #define EA_ID(ea) ((ea) & 0xff)
 487 #define EA_PROTO(ea) ((ea) >> 8)
 488 #define EA_ID_FLAG(ea) (1 << EA_ID(ea))
 489 #define EA_CUSTOM(id) ((id) | EA_CUSTOM_BIT)
 490 #define EA_IS_CUSTOM(ea) ((ea) & EA_CUSTOM_BIT)
 491 #define EA_CUSTOM_ID(ea) ((ea) & ~EA_CUSTOM_BIT)
 492
 493 const char *ea_custom_name(uint ea);
 494
 495 #define EA_GEN_IGP_METRIC EA_CODE(PROTOCOL_NONE, 0)
 496
 497 #define EA_CODE_MASK 0xffff
 498 #define EA_CUSTOM_BIT 0x8000
 499 #define EA_ALLOW_UNDEF 0x10000          /* ea_find: allow EAF_TYPE_UNDEF */
 500 #define EA_BIT(n) ((n) << 24)           /* Used in bitfield accessors */
 501
 502 #define EAF_TYPE_MASK 0x1f              /* Mask with this to get type */
 503 #define EAF_TYPE_INT 0x01               /* 32-bit unsigned integer number */
 504 #define EAF_TYPE_OPAQUE 0x02            /* Opaque byte string (not filterable) */
 505 #define EAF_TYPE_IP_ADDRESS 0x04        /* IP address */
 506 #define EAF_TYPE_ROUTER_ID 0x05         /* Router ID (IPv4 address) */
 507 #define EAF_TYPE_AS_PATH 0x06           /* BGP AS path (encoding per RFC 1771:4.3) */
 508 #define EAF_TYPE_BITFIELD 0x09          /* 32-bit embedded bitfield */
 509 #define EAF_TYPE_INT_SET 0x0a           /* Set of u32's (e.g., a community list) */
 510 #define EAF_TYPE_EC_SET 0x0e            /* Set of pairs of u32's - ext. community list */
 511 #define EAF_TYPE_LC_SET 0x12            /* Set of triplets of u32's - large community list */
 512 #define EAF_TYPE_UNDEF 0x1f             /* `force undefined' entry */
 513 #define EAF_EMBEDDED 0x01               /* Data stored in eattr.u.data (part of type spec) */
 514 #define EAF_VAR_LENGTH 0x02             /* Attribute length is variable (part of type spec) */
 515 #define EAF_ORIGINATED 0x20             /* The attribute has originated locally */
 516 #define EAF_FRESH 0x40                  /* An uncached attribute (e.g. modified in export filter) */
 517
 518 typedef struct adata {
 519   uint length;                          /* Length of data */
 520   byte data[0];
 521 } adata;
 522
 523 static inline struct adata *
 524 lp_alloc_adata(struct linpool *pool, uint len)
 525 {
 526   struct adata *ad = lp_alloc(pool, sizeof(struct adata) + len);
 527   ad->length = len;
 528   return ad;
 529 }
 530
 531 static inline int adata_same(struct adata *a, struct adata *b)
 532 { return (a->length == b->length && !memcmp(a->data, b->data, a->length)); }
 533
 534
 535 typedef struct ea_list {
 536   struct ea_list *next;                 /* In case we have an override list */
 537   byte flags;                           /* Flags: EALF_... */
 538   byte rfu;
 539   word count;                           /* Number of attributes */
 540   eattr attrs[0];                       /* Attribute definitions themselves */
 541 } ea_list;
 542
 543 #define EALF_SORTED 1                   /* Attributes are sorted by code */
 544 #define EALF_BISECT 2                   /* Use interval bisection for searching */
 545 #define EALF_CACHED 4                   /* Attributes belonging to cached rta */
 546 #define EALF_TEMP 8                     /* Temporary ea_list added by make_tmp_attrs hooks */
 547
 548 struct rte_src *rt_find_source(struct proto *p, u32 id);
 549 struct rte_src *rt_get_source(struct proto *p, u32 id);
 550 static inline void rt_lock_source(struct rte_src *src) { src->uc++; }
 551 static inline void rt_unlock_source(struct rte_src *src) { src->uc--; }
 552 void rt_prune_sources(void);
 553
 554 struct ea_walk_state {
 555   ea_list *eattrs;                      /* Ccurrent ea_list, initially set by caller */
 556   eattr *ea;                            /* Current eattr, initially NULL */
 557   u32 visited[4];                       /* Bitfield, limiting max to 128 */
 558 };
 559
 560 eattr *ea_find(ea_list *, unsigned ea);
 561 eattr *ea_walk(struct ea_walk_state *s, uint id, uint max);
 562 int ea_get_int(ea_list *, unsigned ea, int def);
 563 void ea_dump(ea_list *);
 564 void ea_sort(ea_list *);                /* Sort entries in all sub-lists */
 565 unsigned ea_scan(ea_list *);            /* How many bytes do we need for merged ea_list */
 566 void ea_merge(ea_list *from, ea_list *to); /* Merge sub-lists to allocated buffer */
 567 int ea_same(ea_list *x, ea_list *y);    /* Test whether two ea_lists are identical */
 568 uint ea_hash(ea_list *e);       /* Calculate 16-bit hash value */
 569 ea_list *ea_append(ea_list *to, ea_list *what);
 570 void ea_format_bitfield(struct eattr *a, byte *buf, int bufsize, const char **names, int min, int max);
 571
 572 #define ea_normalize(ea) do { \
 573   if (ea->next) { \
 574     ea_list *t = alloca(ea_scan(ea)); \
 575     ea_merge(ea, t); \
 576     ea = t; \
 577   } \
 578   ea_sort(ea); \
 579   if (ea->count == 0) \
 580     ea = NULL; \
 581 } while(0) \
 582
 583 static inline eattr *
 584 ea_set_attr(ea_list **to, struct linpool *pool, uint id, uint flags, uint type, uintptr_t val)
 585 {
 586   ea_list *a = lp_alloc(pool, sizeof(ea_list) + sizeof(eattr));
 587   eattr *e = &a->attrs[0];
 588
 589   a->flags = EALF_SORTED;
 590   a->count = 1;
 591   a->next = *to;
 592   *to = a;
 593
 594   e->id = id;
 595   e->type = type;
 596   e->flags = flags;
 597
 598   if (type & EAF_EMBEDDED)
 599     e->u.data = (u32) val;
 600   else
 601     e->u.ptr = (struct adata *) val;
 602
 603   return e;
 604 }
 605
 606 static inline void
 607 ea_set_attr_u32(ea_list **to, struct linpool *pool, uint id, uint flags, uint type, u32 val)
 608 { ea_set_attr(to, pool, id, flags, type, (uintptr_t) val); }
 609
 610 static inline void
 611 ea_set_attr_ptr(ea_list **to, struct linpool *pool, uint id, uint flags, uint type, struct adata *val)
 612 { ea_set_attr(to, pool, id, flags, type, (uintptr_t) val); }
 613
 614 static inline void
 615 ea_set_attr_data(ea_list **to, struct linpool *pool, uint id, uint flags, uint type, void *data, uint len)
 616 {
 617   struct adata *a = lp_alloc_adata(pool, len);
 618   memcpy(a->data, data, len);
 619   ea_set_attr(to, pool, id, flags, type, (uintptr_t) a);
 620 }
 621
 622
 623 #define NEXTHOP_MAX_SIZE (sizeof(struct nexthop) + sizeof(u32)*MPLS_MAX_LABEL_STACK)
 624
 625 static inline size_t nexthop_size(const struct nexthop *nh)
 626 { return sizeof(struct nexthop) + sizeof(u32)*nh->labels; }
 627 int nexthop__same(struct nexthop *x, struct nexthop *y); /* Compare multipath nexthops */
 628 static inline int nexthop_same(struct nexthop *x, struct nexthop *y)
 629 { return (x == y) || nexthop__same(x, y); }
 630 struct nexthop *nexthop_merge(struct nexthop *x, struct nexthop *y, int rx, int ry, int max, linpool *lp);
 631 static inline void nexthop_link(struct rta *a, struct nexthop *from)
 632 { memcpy(&a->nh, from, nexthop_size(from)); }
 633 void nexthop_insert(struct nexthop **n, struct nexthop *y);
 634 int nexthop_is_sorted(struct nexthop *x);
 635
 636 void rta_init(void);
 637 static inline size_t rta_size(const rta *a) { return sizeof(rta) + sizeof(u32)*a->nh.labels; }
 638 #define RTA_MAX_SIZE (sizeof(rta) + sizeof(u32)*MPLS_MAX_LABEL_STACK)
 639 rta *rta_lookup(rta *);                 /* Get rta equivalent to this one, uc++ */
 640 static inline int rta_is_cached(rta *r) { return r->aflags & RTAF_CACHED; }
 641 static inline rta *rta_clone(rta *r) { r->uc++; return r; }
 642 void rta__free(rta *r);
 643 static inline void rta_free(rta *r) { if (r && !--r->uc) rta__free(r); }
 644 rta *rta_do_cow(rta *o, linpool *lp);
 645 static inline rta * rta_cow(rta *r, linpool *lp) { return rta_is_cached(r) ? rta_do_cow(r, lp) : r; }
 646 void rta_dump(rta *);
 647 void rta_dump_all(void);
 648 void rta_show(struct cli *, rta *);
 649
 650 struct hostentry * rt_get_hostentry(rtable *tab, ip_addr a, ip_addr ll, rtable *dep);
 651 void rta_apply_hostentry(rta *a, struct hostentry *he, mpls_label_stack *mls);
 652
 653 static inline void
 654 rta_set_recursive_next_hop(rtable *dep, rta *a, rtable *tab, ip_addr gw, ip_addr ll, mpls_label_stack *mls)
 655 {
 656   rta_apply_hostentry(a, rt_get_hostentry(tab, gw, ll, dep), mls);
 657 }
 658
 659 /*
 660  * rta_set_recursive_next_hop() acquires hostentry from hostcache and fills
 661  * rta->hostentry field.  New hostentry has zero use count. Cached rta locks its
 662  * hostentry (increases its use count), uncached rta does not lock it. Hostentry
 663  * with zero use count is removed asynchronously during host cache update,
 664  * therefore it is safe to hold such hostentry temorarily. Hostentry holds a
 665  * lock for a 'source' rta, mainly to share multipath nexthops.
 666  *
 667  * There is no need to hold a lock for hostentry->dep table, because that table
 668  * contains routes responsible for that hostentry, and therefore is non-empty if
 669  * given hostentry has non-zero use count. If the hostentry has zero use count,
 670  * the entry is removed before dep is referenced.
 671  *
 672  * The protocol responsible for routes with recursive next hops should hold a
 673  * lock for a 'source' table governing that routes (argument tab to
 674  * rta_set_recursive_next_hop()), because its routes reference hostentries
 675  * (through rta) related to the governing table. When all such routes are
 676  * removed, rtas are immediately removed achieving zero uc. Then the 'source'
 677  * table lock could be immediately released, although hostentries may still
 678  * exist - they will be freed together with the 'source' table.
 679  */
 680
 681 static inline void rt_lock_hostentry(struct hostentry *he) { if (he) he->uc++; }
 682 static inline void rt_unlock_hostentry(struct hostentry *he) { if (he) he->uc--; }
 683
 684 /*
 685  *      Default protocol preferences
 686  */
 687
 688 #define DEF_PREF_DIRECT         240     /* Directly connected */
 689 #define DEF_PREF_STATIC         200     /* Static route */
 690 #define DEF_PREF_OSPF           150     /* OSPF intra-area, inter-area and type 1 external routes */
 691 #define DEF_PREF_BABEL          130     /* Babel */
 692 #define DEF_PREF_RIP            120     /* RIP */
 693 #define DEF_PREF_BGP            100     /* BGP */
 694 #define DEF_PREF_RPKI           100     /* RPKI */
 695 #define DEF_PREF_INHERITED      10      /* Routes inherited from other routing daemons */
 696
 697 /*
 698  *      Route Origin Authorization
 699  */
 700
 701 #define ROA_UNKNOWN     0
 702 #define ROA_VALID       1
 703 #define ROA_INVALID     2
 704
 705 #endif