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/bitmap.h"
14 #include "lib/resource.h"
15 #include "lib/net.h"
16 
17 struct ea_list;
18 struct protocol;
19 struct proto;
20 struct rte_src;
21 struct symbol;
22 struct timer;
23 struct filter;
24 struct cli;
25 
26 /*
27  *	Generic data structure for storing network prefixes. Also used
28  *	for the master routing table. Currently implemented as a hash
29  *	table.
30  *
31  *	Available operations:
32  *		- insertion of new entry
33  *		- deletion of entry
34  *		- searching for entry by network prefix
35  *		- asynchronous retrieval of fib contents
36  */
37 
38 struct fib_node {
39   struct fib_node *next;		/* Next in hash chain */
40   struct fib_iterator *readers;		/* List of readers of this node */
41   net_addr addr[0];
42 };
43 
44 struct fib_iterator {			/* See lib/slists.h for an explanation */
45   struct fib_iterator *prev, *next;	/* Must be synced with struct fib_node! */
46   byte efef;				/* 0xff to distinguish between iterator and node */
47   byte pad[3];
48   struct fib_node *node;		/* Or NULL if freshly merged */
49   uint hash;
50 };
51 
52 typedef void (*fib_init_fn)(void *);
53 
54 struct fib {
55   pool *fib_pool;			/* Pool holding all our data */
56   slab *fib_slab;			/* Slab holding all fib nodes */
57   struct fib_node **hash_table;		/* Node hash table */
58   uint hash_size;			/* Number of hash table entries (a power of two) */
59   uint hash_order;			/* Binary logarithm of hash_size */
60   uint hash_shift;			/* 32 - hash_order */
61   uint addr_type;			/* Type of address data stored in fib (NET_*) */
62   uint node_size;			/* FIB node size, 0 for nonuniform */
63   uint node_offset;			/* Offset of fib_node struct inside of user data */
64   uint entries;				/* Number of entries */
65   uint entries_min, entries_max;	/* Entry count limits (else start rehashing) */
66   fib_init_fn init;			/* Constructor */
67 };
68 
fib_node_to_user(struct fib * f,struct fib_node * e)69 static inline void * fib_node_to_user(struct fib *f, struct fib_node *e)
70 { return e ? (void *) ((char *) e - f->node_offset) : NULL; }
71 
fib_user_to_node(struct fib * f,void * e)72 static inline struct fib_node * fib_user_to_node(struct fib *f, void *e)
73 { return e ? (void *) ((char *) e + f->node_offset) : NULL; }
74 
75 void fib_init(struct fib *f, pool *p, uint addr_type, uint node_size, uint node_offset, uint hash_order, fib_init_fn init);
76 void *fib_find(struct fib *, const net_addr *);	/* Find or return NULL if doesn't exist */
77 void *fib_get_chain(struct fib *f, const net_addr *a); /* Find first node in linked list from hash table */
78 void *fib_get(struct fib *, const net_addr *);	/* Find or create new if nonexistent */
79 void *fib_route(struct fib *, const net_addr *); /* Longest-match routing lookup */
80 void fib_delete(struct fib *, void *);	/* Remove fib entry */
81 void fib_free(struct fib *);		/* Destroy the fib */
82 void fib_check(struct fib *);		/* Consistency check for debugging */
83 
84 void fit_init(struct fib_iterator *, struct fib *); /* Internal functions, don't call */
85 struct fib_node *fit_get(struct fib *, struct fib_iterator *);
86 void fit_put(struct fib_iterator *, struct fib_node *);
87 void fit_put_next(struct fib *f, struct fib_iterator *i, struct fib_node *n, uint hpos);
88 void fit_put_end(struct fib_iterator *i);
89 void fit_copy(struct fib *f, struct fib_iterator *dst, struct fib_iterator *src);
90 
91 
92 #define FIB_WALK(fib, type, z) do {				\
93 	struct fib_node *fn_, **ff_ = (fib)->hash_table;	\
94 	uint count_ = (fib)->hash_size;				\
95 	type *z;						\
96 	while (count_--)					\
97 	  for (fn_ = *ff_++; z = fib_node_to_user(fib, fn_); fn_=fn_->next)
98 
99 #define FIB_WALK_END } while (0)
100 
101 #define FIB_ITERATE_INIT(it, fib) fit_init(it, fib)
102 
103 #define FIB_ITERATE_START(fib, it, type, z) do {		\
104 	struct fib_node *fn_ = fit_get(fib, it);		\
105 	uint count_ = (fib)->hash_size;				\
106 	uint hpos_ = (it)->hash;				\
107 	type *z;						\
108 	for(;;) {						\
109 	  if (!fn_)						\
110 	    {							\
111 	       if (++hpos_ >= count_)				\
112 		 break;						\
113 	       fn_ = (fib)->hash_table[hpos_];			\
114 	       continue;					\
115 	    }							\
116 	  z = fib_node_to_user(fib, fn_);
117 
118 #define FIB_ITERATE_END fn_ = fn_->next; } } while(0)
119 
120 #define FIB_ITERATE_PUT(it) fit_put(it, fn_)
121 
122 #define FIB_ITERATE_PUT_NEXT(it, fib) fit_put_next(fib, it, fn_, hpos_)
123 
124 #define FIB_ITERATE_PUT_END(it) fit_put_end(it)
125 
126 #define FIB_ITERATE_UNLINK(it, fib) fit_get(fib, it)
127 
128 #define FIB_ITERATE_COPY(dst, src, fib) fit_copy(fib, dst, src)
129 
130 
131 /*
132  *	Master Routing Tables. Generally speaking, each of them contains a FIB
133  *	with each entry pointing to a list of route entries representing routes
134  *	to given network (with the selected one at the head).
135  *
136  *	Each of the RTE's contains variable data (the preference and protocol-dependent
137  *	metrics) and a pointer to a route attribute block common for many routes).
138  *
139  *	It's guaranteed that there is at most one RTE for every (prefix,proto) pair.
140  */
141 
142 struct rtable_config {
143   node n;
144   char *name;
145   struct rtable *table;
146   struct proto_config *krt_attached;	/* Kernel syncer attached to this table */
147   uint addr_type;			/* Type of address data stored in table (NET_*) */
148   int gc_max_ops;			/* Maximum number of operations before GC is run */
149   int gc_min_time;			/* Minimum time between two consecutive GC runs */
150   byte sorted;				/* Routes of network are sorted according to rte_better() */
151   btime min_settle_time;		/* Minimum settle time for notifications */
152   btime max_settle_time;		/* Maximum settle time for notifications */
153 };
154 
155 typedef struct rtable {
156   node n;				/* Node in list of all tables */
157   struct fib fib;
158   char *name;				/* Name of this table */
159   list channels;			/* List of attached channels (struct channel) */
160   uint addr_type;			/* Type of address data stored in table (NET_*) */
161   int pipe_busy;			/* Pipe loop detection */
162   int use_count;			/* Number of protocols using this table */
163   u32 rt_count;				/* Number of routes in the table */
164   struct hmap id_map;
165   struct hostcache *hostcache;
166   struct rtable_config *config;		/* Configuration of this table */
167   struct config *deleted;		/* Table doesn't exist in current configuration,
168 					 * delete as soon as use_count becomes 0 and remove
169 					 * obstacle from this routing table.
170 					 */
171   struct event *rt_event;		/* Routing table event */
172   btime last_rt_change;			/* Last time when route changed */
173   btime base_settle_time;		/* Start time of rtable settling interval */
174   btime gc_time;			/* Time of last GC */
175   int gc_counter;			/* Number of operations since last GC */
176   byte prune_state;			/* Table prune state, 1 -> scheduled, 2-> running */
177   byte hcu_scheduled;			/* Hostcache update is scheduled */
178   byte nhu_state;			/* Next Hop Update state */
179   struct fib_iterator prune_fit;	/* Rtable prune FIB iterator */
180   struct fib_iterator nhu_fit;		/* Next Hop Update FIB iterator */
181 
182   list subscribers;			/* Subscribers for notifications */
183   struct timer *settle_timer;		/* Settle time for notifications */
184 } rtable;
185 
186 struct rt_subscription {
187   node n;
188   rtable *tab;
189   void (*hook)(struct rt_subscription *b);
190   void *data;
191 };
192 
193 #define NHU_CLEAN	0
194 #define NHU_SCHEDULED	1
195 #define NHU_RUNNING	2
196 #define NHU_DIRTY	3
197 
198 typedef struct network {
199   struct rte *routes;			/* Available routes for this network */
200   struct fib_node n;			/* FIB flags reserved for kernel syncer */
201 } net;
202 
203 struct hostcache {
204   slab *slab;				/* Slab holding all hostentries */
205   struct hostentry **hash_table;	/* Hash table for hostentries */
206   unsigned hash_order, hash_shift;
207   unsigned hash_max, hash_min;
208   unsigned hash_items;
209   linpool *lp;				/* Linpool for trie */
210   struct f_trie *trie;			/* Trie of prefixes that might affect hostentries */
211   list hostentries;			/* List of all hostentries */
212   byte update_hostcache;
213 };
214 
215 struct hostentry {
216   node ln;
217   ip_addr addr;				/* IP address of host, part of key */
218   ip_addr link;				/* (link-local) IP address of host, used as gw
219 					   if host is directly attached */
220   struct rtable *tab;			/* Dependent table, part of key */
221   struct hostentry *next;		/* Next in hash chain */
222   unsigned hash_key;			/* Hash key */
223   unsigned uc;				/* Use count */
224   struct rta *src;			/* Source rta entry */
225   byte dest;				/* Chosen route destination type (RTD_...) */
226   byte nexthop_linkable;		/* Nexthop list is completely non-device */
227   u32 igp_metric;			/* Chosen route IGP metric */
228 };
229 
230 typedef struct rte {
231   struct rte *next;
232   net *net;				/* Network this RTE belongs to */
233   struct channel *sender;		/* Channel used to send the route to the routing table */
234   struct rta *attrs;			/* Attributes of this route */
235   u32 id;				/* Table specific route id */
236   byte flags;				/* Flags (REF_...) */
237   byte pflags;				/* Protocol-specific flags */
238   word pref;				/* Route preference */
239   btime lastmod;			/* Last modified */
240   union {				/* Protocol-dependent data (metrics etc.) */
241 #ifdef CONFIG_RIP
242     struct {
243       struct iface *from;		/* Incoming iface */
244       u8 metric;			/* RIP metric */
245       u16 tag;				/* External route tag */
246     } rip;
247 #endif
248 #ifdef CONFIG_OSPF
249     struct {
250       u32 metric1, metric2;		/* OSPF Type 1 and Type 2 metrics */
251       u32 tag;				/* External route tag */
252       u32 router_id;			/* Router that originated this route */
253     } ospf;
254 #endif
255 #ifdef CONFIG_BGP
256     struct {
257       u8 suppressed;			/* Used for deterministic MED comparison */
258       s8 stale;				/* Route is LLGR_STALE, -1 if unknown */
259     } bgp;
260 #endif
261 #ifdef CONFIG_BABEL
262     struct {
263       u16 seqno;			/* Babel seqno */
264       u16 metric;			/* Babel metric */
265       u64 router_id;			/* Babel router id */
266     } babel;
267 #endif
268     struct {				/* Routes generated by krt sync (both temporary and inherited ones) */
269       s8 src;				/* Alleged route source (see krt.h) */
270       u8 proto;				/* Kernel source protocol ID */
271       u8 seen;				/* Seen during last scan */
272       u8 best;				/* Best route in network, propagated to core */
273       u32 metric;			/* Kernel metric */
274     } krt;
275   } u;
276 } rte;
277 
278 #define REF_COW		1		/* Copy this rte on write */
279 #define REF_FILTERED	2		/* Route is rejected by import filter */
280 #define REF_STALE	4		/* Route is stale in a refresh cycle */
281 #define REF_DISCARD	8		/* Route is scheduled for discard */
282 #define REF_MODIFY	16		/* Route is scheduled for modify */
283 
284 /* Route is valid for propagation (may depend on other flags in the future), accepts NULL */
rte_is_valid(rte * r)285 static inline int rte_is_valid(rte *r) { return r && !(r->flags & REF_FILTERED); }
286 
287 /* Route just has REF_FILTERED flag */
rte_is_filtered(rte * r)288 static inline int rte_is_filtered(rte *r) { return !!(r->flags & REF_FILTERED); }
289 
290 
291 /* Types of route announcement, also used as flags */
292 #define RA_UNDEF	0		/* Undefined RA type */
293 #define RA_OPTIMAL	1		/* Announcement of optimal route change */
294 #define RA_ACCEPTED	2		/* Announcement of first accepted route */
295 #define RA_ANY		3		/* Announcement of any route change */
296 #define RA_MERGED	4		/* Announcement of optimal route merged with next ones */
297 
298 /* Return value of preexport() callback */
299 #define RIC_ACCEPT	1		/* Accepted by protocol */
300 #define RIC_PROCESS	0		/* Process it through import filter */
301 #define RIC_REJECT	-1		/* Rejected by protocol */
302 #define RIC_DROP	-2		/* Silently dropped by protocol */
303 
304 extern list routing_tables;
305 struct config;
306 
307 void rt_init(void);
308 void rt_preconfig(struct config *);
309 void rt_commit(struct config *new, struct config *old);
310 void rt_lock_table(rtable *);
311 void rt_unlock_table(rtable *);
312 void rt_subscribe(rtable *tab, struct rt_subscription *s);
313 void rt_unsubscribe(struct rt_subscription *s);
314 void rt_setup(pool *, rtable *, struct rtable_config *);
net_find(rtable * tab,const net_addr * addr)315 static inline net *net_find(rtable *tab, const net_addr *addr) { return (net *) fib_find(&tab->fib, addr); }
net_find_valid(rtable * tab,const net_addr * addr)316 static inline net *net_find_valid(rtable *tab, const net_addr *addr)
317 { net *n = net_find(tab, addr); return (n && rte_is_valid(n->routes)) ? n : NULL; }
net_get(rtable * tab,const net_addr * addr)318 static inline net *net_get(rtable *tab, const net_addr *addr) { return (net *) fib_get(&tab->fib, addr); }
319 void *net_route(rtable *tab, const net_addr *n);
320 int net_roa_check(rtable *tab, const net_addr *n, u32 asn);
321 rte *rte_find(net *net, struct rte_src *src);
322 rte *rte_get_temp(struct rta *);
323 void rte_update2(struct channel *c, const net_addr *n, rte *new, struct rte_src *src);
324 /* rte_update() moved to protocol.h to avoid dependency conflicts */
325 int rt_examine(rtable *t, net_addr *a, struct proto *p, const struct filter *filter);
326 rte *rt_export_merged(struct channel *c, net *net, rte **rt_free, linpool *pool, int silent);
327 void rt_refresh_begin(rtable *t, struct channel *c);
328 void rt_refresh_end(rtable *t, struct channel *c);
329 void rt_modify_stale(rtable *t, struct channel *c);
330 void rt_schedule_prune(rtable *t);
331 void rte_dump(rte *);
332 void rte_free(rte *);
333 rte *rte_do_cow(rte *);
rte_cow(rte * r)334 static inline rte * rte_cow(rte *r) { return (r->flags & REF_COW) ? rte_do_cow(r) : r; }
335 rte *rte_cow_rta(rte *r, linpool *lp);
336 void rte_init_tmp_attrs(struct rte *r, linpool *lp, uint max);
337 void rte_make_tmp_attr(struct rte *r, uint id, uint type, uintptr_t val);
338 void rte_make_tmp_attrs(struct rte **r, struct linpool *pool, struct rta **old_attrs);
339 uintptr_t rte_store_tmp_attr(struct rte *r, uint id);
340 void rt_dump(rtable *);
341 void rt_dump_all(void);
342 int rt_feed_channel(struct channel *c);
343 void rt_feed_channel_abort(struct channel *c);
344 int rte_update_in(struct channel *c, const net_addr *n, rte *new, struct rte_src *src);
345 int rt_reload_channel(struct channel *c);
346 void rt_reload_channel_abort(struct channel *c);
347 void rt_prune_sync(rtable *t, int all);
348 int rte_update_out(struct channel *c, const net_addr *n, rte *new, rte *old0, int refeed);
349 struct rtable_config *rt_new_table(struct symbol *s, uint addr_type);
350 
351 
352 /* Default limit for ECMP next hops, defined in sysdep code */
353 extern const int rt_default_ecmp;
354 
355 struct rt_show_data_rtable {
356   node n;
357   rtable *table;
358   struct channel *export_channel;
359 };
360 
361 struct rt_show_data {
362   net_addr *addr;
363   list tables;
364   struct rt_show_data_rtable *tab;	/* Iterator over table list */
365   struct rt_show_data_rtable *last_table; /* Last table in output */
366   struct fib_iterator fit;		/* Iterator over networks in table */
367   int verbose, tables_defined_by;
368   const struct filter *filter;
369   struct proto *show_protocol;
370   struct proto *export_protocol;
371   struct channel *export_channel;
372   struct config *running_on_config;
373   struct krt_proto *kernel;
374   int export_mode, primary_only, filtered, stats, show_for;
375 
376   int table_open;			/* Iteration (fit) is open */
377   int net_counter, rt_counter, show_counter, table_counter;
378   int net_counter_last, rt_counter_last, show_counter_last;
379 };
380 
381 void rt_show(struct rt_show_data *);
382 struct rt_show_data_rtable * rt_show_add_table(struct rt_show_data *d, rtable *t);
383 
384 /* Value of table definition mode in struct rt_show_data */
385 #define RSD_TDB_DEFAULT	  0		/* no table specified */
386 #define RSD_TDB_INDIRECT  0		/* show route ... protocol P ... */
387 #define RSD_TDB_ALL	  RSD_TDB_SET			/* show route ... table all ... */
388 #define RSD_TDB_DIRECT	  RSD_TDB_SET | RSD_TDB_NMN	/* show route ... table X table Y ... */
389 
390 #define RSD_TDB_SET	  0x1		/* internal: show empty tables */
391 #define RSD_TDB_NMN	  0x2		/* internal: need matching net */
392 
393 /* Value of export_mode in struct rt_show_data */
394 #define RSEM_NONE	0		/* Export mode not used */
395 #define RSEM_PREEXPORT	1		/* Routes ready for export, before filtering */
396 #define RSEM_EXPORT	2		/* Routes accepted by export filter */
397 #define RSEM_NOEXPORT	3		/* Routes rejected by export filter */
398 #define RSEM_EXPORTED	4		/* Routes marked in export map */
399 
400 /*
401  *	Route Attributes
402  *
403  *	Beware: All standard BGP attributes must be represented here instead
404  *	of making them local to the route. This is needed to ensure proper
405  *	construction of BGP route attribute lists.
406  */
407 
408 /* Nexthop structure */
409 struct nexthop {
410   ip_addr gw;				/* Next hop */
411   struct iface *iface;			/* Outgoing interface */
412   struct nexthop *next;
413   byte flags;
414   byte weight;
415   byte labels_orig;			/* Number of labels before hostentry was applied */
416   byte labels;				/* Number of all labels */
417   u32 label[0];
418 };
419 
420 #define RNF_ONLINK		0x1	/* Gateway is onlink regardless of IP ranges */
421 
422 
423 struct rte_src {
424   struct rte_src *next;			/* Hash chain */
425   struct proto *proto;			/* Protocol the source is based on */
426   u32 private_id;			/* Private ID, assigned by the protocol */
427   u32 global_id;			/* Globally unique ID of the source */
428   unsigned uc;				/* Use count */
429 };
430 
431 
432 typedef struct rta {
433   struct rta *next, **pprev;		/* Hash chain */
434   u32 uc;				/* Use count */
435   u32 hash_key;				/* Hash over important fields */
436   struct ea_list *eattrs;		/* Extended Attribute chain */
437   struct rte_src *src;			/* Route source that created the route */
438   struct hostentry *hostentry;		/* Hostentry for recursive next-hops */
439   ip_addr from;				/* Advertising router */
440   u32 igp_metric;			/* IGP metric to next hop (for iBGP routes) */
441   u8 source;				/* Route source (RTS_...) */
442   u8 scope;				/* Route scope (SCOPE_... -- see ip.h) */
443   u8 dest;				/* Route destination type (RTD_...) */
444   u8 aflags;
445   struct nexthop nh;			/* Next hop */
446 } rta;
447 
448 #define RTS_DUMMY 0			/* Dummy route to be removed soon */
449 #define RTS_STATIC 1			/* Normal static route */
450 #define RTS_INHERIT 2			/* Route inherited from kernel */
451 #define RTS_DEVICE 3			/* Device route */
452 #define RTS_STATIC_DEVICE 4		/* Static device route */
453 #define RTS_REDIRECT 5			/* Learned via redirect */
454 #define RTS_RIP 6			/* RIP route */
455 #define RTS_OSPF 7			/* OSPF route */
456 #define RTS_OSPF_IA 8			/* OSPF inter-area route */
457 #define RTS_OSPF_EXT1 9			/* OSPF external route type 1 */
458 #define RTS_OSPF_EXT2 10		/* OSPF external route type 2 */
459 #define RTS_BGP 11			/* BGP route */
460 #define RTS_PIPE 12			/* Inter-table wormhole */
461 #define RTS_BABEL 13			/* Babel route */
462 #define RTS_RPKI 14			/* Route Origin Authorization */
463 #define RTS_PERF 15			/* Perf checker */
464 #define RTS_MAX 16
465 
466 #define RTC_UNICAST 0
467 #define RTC_BROADCAST 1
468 #define RTC_MULTICAST 2
469 #define RTC_ANYCAST 3			/* IPv6 Anycast */
470 
471 #define RTD_NONE 0			/* Undefined next hop */
472 #define RTD_UNICAST 1			/* Next hop is neighbor router */
473 #define RTD_BLACKHOLE 2			/* Silently drop packets */
474 #define RTD_UNREACHABLE 3		/* Reject as unreachable */
475 #define RTD_PROHIBIT 4			/* Administratively prohibited */
476 #define RTD_MAX 5
477 
478 #define RTAF_CACHED 1			/* This is a cached rta */
479 
480 #define IGP_METRIC_UNKNOWN 0x80000000	/* Default igp_metric used when no other
481 					   protocol-specific metric is availabe */
482 
483 
484 extern const char * rta_dest_names[RTD_MAX];
485 
rta_dest_name(uint n)486 static inline const char *rta_dest_name(uint n)
487 { return (n < RTD_MAX) ? rta_dest_names[n] : "???"; }
488 
489 /* Route has regular, reachable nexthop (i.e. not RTD_UNREACHABLE and like) */
rte_is_reachable(rte * r)490 static inline int rte_is_reachable(rte *r)
491 { return r->attrs->dest == RTD_UNICAST; }
492 
493 
494 /*
495  *	Extended Route Attributes
496  */
497 
498 typedef struct eattr {
499   word id;				/* EA_CODE(PROTOCOL_..., protocol-dependent ID) */
500   byte flags;				/* Protocol-dependent flags */
501   byte type;				/* Attribute type and several flags (EAF_...) */
502   union {
503     u32 data;
504     const struct adata *ptr;			/* Attribute data elsewhere */
505   } u;
506 } eattr;
507 
508 
509 #define EA_CODE(proto,id) (((proto) << 8) | (id))
510 #define EA_ID(ea) ((ea) & 0xff)
511 #define EA_PROTO(ea) ((ea) >> 8)
512 #define EA_ID_FLAG(ea) (1 << EA_ID(ea))
513 #define EA_CUSTOM(id) ((id) | EA_CUSTOM_BIT)
514 #define EA_IS_CUSTOM(ea) ((ea) & EA_CUSTOM_BIT)
515 #define EA_CUSTOM_ID(ea) ((ea) & ~EA_CUSTOM_BIT)
516 
517 const char *ea_custom_name(uint ea);
518 
519 #define EA_GEN_IGP_METRIC EA_CODE(PROTOCOL_NONE, 0)
520 
521 #define EA_CODE_MASK 0xffff
522 #define EA_CUSTOM_BIT 0x8000
523 #define EA_ALLOW_UNDEF 0x10000		/* ea_find: allow EAF_TYPE_UNDEF */
524 #define EA_BIT(n) ((n) << 24)		/* Used in bitfield accessors */
525 #define EA_BIT_GET(ea) ((ea) >> 24)
526 
527 #define EAF_TYPE_MASK 0x1f		/* Mask with this to get type */
528 #define EAF_TYPE_INT 0x01		/* 32-bit unsigned integer number */
529 #define EAF_TYPE_OPAQUE 0x02		/* Opaque byte string (not filterable) */
530 #define EAF_TYPE_IP_ADDRESS 0x04	/* IP address */
531 #define EAF_TYPE_ROUTER_ID 0x05		/* Router ID (IPv4 address) */
532 #define EAF_TYPE_AS_PATH 0x06		/* BGP AS path (encoding per RFC 1771:4.3) */
533 #define EAF_TYPE_BITFIELD 0x09		/* 32-bit embedded bitfield */
534 #define EAF_TYPE_INT_SET 0x0a		/* Set of u32's (e.g., a community list) */
535 #define EAF_TYPE_EC_SET 0x0e		/* Set of pairs of u32's - ext. community list */
536 #define EAF_TYPE_LC_SET 0x12		/* Set of triplets of u32's - large community list */
537 #define EAF_TYPE_UNDEF 0x1f		/* `force undefined' entry */
538 #define EAF_EMBEDDED 0x01		/* Data stored in eattr.u.data (part of type spec) */
539 #define EAF_VAR_LENGTH 0x02		/* Attribute length is variable (part of type spec) */
540 #define EAF_ORIGINATED 0x20		/* The attribute has originated locally */
541 #define EAF_FRESH 0x40			/* An uncached attribute (e.g. modified in export filter) */
542 
543 typedef struct adata {
544   uint length;				/* Length of data */
545   byte data[0];
546 } adata;
547 
548 extern const adata null_adata;		/* adata of length 0 */
549 
550 static inline struct adata *
lp_alloc_adata(struct linpool * pool,uint len)551 lp_alloc_adata(struct linpool *pool, uint len)
552 {
553   struct adata *ad = lp_alloc(pool, sizeof(struct adata) + len);
554   ad->length = len;
555   return ad;
556 }
557 
adata_same(const struct adata * a,const struct adata * b)558 static inline int adata_same(const struct adata *a, const struct adata *b)
559 { return (a->length == b->length && !memcmp(a->data, b->data, a->length)); }
560 
561 
562 typedef struct ea_list {
563   struct ea_list *next;			/* In case we have an override list */
564   byte flags;				/* Flags: EALF_... */
565   byte rfu;
566   word count;				/* Number of attributes */
567   eattr attrs[0];			/* Attribute definitions themselves */
568 } ea_list;
569 
570 #define EALF_SORTED 1			/* Attributes are sorted by code */
571 #define EALF_BISECT 2			/* Use interval bisection for searching */
572 #define EALF_CACHED 4			/* Attributes belonging to cached rta */
573 #define EALF_TEMP 8			/* Temporary ea_list added by make_tmp_attrs hooks */
574 
575 struct rte_src *rt_find_source(struct proto *p, u32 id);
576 struct rte_src *rt_get_source(struct proto *p, u32 id);
rt_lock_source(struct rte_src * src)577 static inline void rt_lock_source(struct rte_src *src) { src->uc++; }
rt_unlock_source(struct rte_src * src)578 static inline void rt_unlock_source(struct rte_src *src) { src->uc--; }
579 void rt_prune_sources(void);
580 
581 struct ea_walk_state {
582   ea_list *eattrs;			/* Ccurrent ea_list, initially set by caller */
583   eattr *ea;				/* Current eattr, initially NULL */
584   u32 visited[4];			/* Bitfield, limiting max to 128 */
585 };
586 
587 eattr *ea_find(ea_list *, unsigned ea);
588 eattr *ea_walk(struct ea_walk_state *s, uint id, uint max);
589 int ea_get_int(ea_list *, unsigned ea, int def);
590 void ea_dump(ea_list *);
591 void ea_sort(ea_list *);		/* Sort entries in all sub-lists */
592 unsigned ea_scan(ea_list *);		/* How many bytes do we need for merged ea_list */
593 void ea_merge(ea_list *from, ea_list *to); /* Merge sub-lists to allocated buffer */
594 int ea_same(ea_list *x, ea_list *y);	/* Test whether two ea_lists are identical */
595 uint ea_hash(ea_list *e);	/* Calculate 16-bit hash value */
596 ea_list *ea_append(ea_list *to, ea_list *what);
597 void ea_format_bitfield(const struct eattr *a, byte *buf, int bufsize, const char **names, int min, int max);
598 
599 #define ea_normalize(ea) do { \
600   if (ea->next) { \
601     ea_list *t = alloca(ea_scan(ea)); \
602     ea_merge(ea, t); \
603     ea = t; \
604   } \
605   ea_sort(ea); \
606   if (ea->count == 0) \
607     ea = NULL; \
608 } while(0) \
609 
610 static inline eattr *
ea_set_attr(ea_list ** to,struct linpool * pool,uint id,uint flags,uint type,uintptr_t val)611 ea_set_attr(ea_list **to, struct linpool *pool, uint id, uint flags, uint type, uintptr_t val)
612 {
613   ea_list *a = lp_alloc(pool, sizeof(ea_list) + sizeof(eattr));
614   eattr *e = &a->attrs[0];
615 
616   a->flags = EALF_SORTED;
617   a->count = 1;
618   a->next = *to;
619   *to = a;
620 
621   e->id = id;
622   e->type = type;
623   e->flags = flags;
624 
625   if (type & EAF_EMBEDDED)
626     e->u.data = (u32) val;
627   else
628     e->u.ptr = (struct adata *) val;
629 
630   return e;
631 }
632 
633 static inline void
ea_set_attr_u32(ea_list ** to,struct linpool * pool,uint id,uint flags,uint type,u32 val)634 ea_set_attr_u32(ea_list **to, struct linpool *pool, uint id, uint flags, uint type, u32 val)
635 { ea_set_attr(to, pool, id, flags, type, (uintptr_t) val); }
636 
637 static inline void
ea_set_attr_ptr(ea_list ** to,struct linpool * pool,uint id,uint flags,uint type,struct adata * val)638 ea_set_attr_ptr(ea_list **to, struct linpool *pool, uint id, uint flags, uint type, struct adata *val)
639 { ea_set_attr(to, pool, id, flags, type, (uintptr_t) val); }
640 
641 static inline void
ea_set_attr_data(ea_list ** to,struct linpool * pool,uint id,uint flags,uint type,void * data,uint len)642 ea_set_attr_data(ea_list **to, struct linpool *pool, uint id, uint flags, uint type, void *data, uint len)
643 {
644   struct adata *a = lp_alloc_adata(pool, len);
645   memcpy(a->data, data, len);
646   ea_set_attr(to, pool, id, flags, type, (uintptr_t) a);
647 }
648 
649 
650 #define NEXTHOP_MAX_SIZE (sizeof(struct nexthop) + sizeof(u32)*MPLS_MAX_LABEL_STACK)
651 
nexthop_size(const struct nexthop * nh)652 static inline size_t nexthop_size(const struct nexthop *nh)
653 { return sizeof(struct nexthop) + sizeof(u32)*nh->labels; }
654 int nexthop__same(struct nexthop *x, struct nexthop *y); /* Compare multipath nexthops */
nexthop_same(struct nexthop * x,struct nexthop * y)655 static inline int nexthop_same(struct nexthop *x, struct nexthop *y)
656 { return (x == y) || nexthop__same(x, y); }
657 struct nexthop *nexthop_merge(struct nexthop *x, struct nexthop *y, int rx, int ry, int max, linpool *lp);
658 struct nexthop *nexthop_sort(struct nexthop *x);
nexthop_link(struct rta * a,struct nexthop * from)659 static inline void nexthop_link(struct rta *a, struct nexthop *from)
660 { memcpy(&a->nh, from, nexthop_size(from)); }
661 void nexthop_insert(struct nexthop **n, struct nexthop *y);
662 int nexthop_is_sorted(struct nexthop *x);
663 
664 void rta_init(void);
rta_size(const rta * a)665 static inline size_t rta_size(const rta *a) { return sizeof(rta) + sizeof(u32)*a->nh.labels; }
666 #define RTA_MAX_SIZE (sizeof(rta) + sizeof(u32)*MPLS_MAX_LABEL_STACK)
667 rta *rta_lookup(rta *);			/* Get rta equivalent to this one, uc++ */
rta_is_cached(rta * r)668 static inline int rta_is_cached(rta *r) { return r->aflags & RTAF_CACHED; }
rta_clone(rta * r)669 static inline rta *rta_clone(rta *r) { r->uc++; return r; }
670 void rta__free(rta *r);
rta_free(rta * r)671 static inline void rta_free(rta *r) { if (r && !--r->uc) rta__free(r); }
672 rta *rta_do_cow(rta *o, linpool *lp);
rta_cow(rta * r,linpool * lp)673 static inline rta * rta_cow(rta *r, linpool *lp) { return rta_is_cached(r) ? rta_do_cow(r, lp) : r; }
674 void rta_dump(rta *);
675 void rta_dump_all(void);
676 void rta_show(struct cli *, rta *);
677 
678 u32 rt_get_igp_metric(rte *rt);
679 struct hostentry * rt_get_hostentry(rtable *tab, ip_addr a, ip_addr ll, rtable *dep);
680 void rta_apply_hostentry(rta *a, struct hostentry *he, mpls_label_stack *mls);
681 
682 static inline void
rta_set_recursive_next_hop(rtable * dep,rta * a,rtable * tab,ip_addr gw,ip_addr ll,mpls_label_stack * mls)683 rta_set_recursive_next_hop(rtable *dep, rta *a, rtable *tab, ip_addr gw, ip_addr ll, mpls_label_stack *mls)
684 {
685   rta_apply_hostentry(a, rt_get_hostentry(tab, gw, ll, dep), mls);
686 }
687 
688 /*
689  * rta_set_recursive_next_hop() acquires hostentry from hostcache and fills
690  * rta->hostentry field.  New hostentry has zero use count. Cached rta locks its
691  * hostentry (increases its use count), uncached rta does not lock it. Hostentry
692  * with zero use count is removed asynchronously during host cache update,
693  * therefore it is safe to hold such hostentry temorarily. Hostentry holds a
694  * lock for a 'source' rta, mainly to share multipath nexthops.
695  *
696  * There is no need to hold a lock for hostentry->dep table, because that table
697  * contains routes responsible for that hostentry, and therefore is non-empty if
698  * given hostentry has non-zero use count. If the hostentry has zero use count,
699  * the entry is removed before dep is referenced.
700  *
701  * The protocol responsible for routes with recursive next hops should hold a
702  * lock for a 'source' table governing that routes (argument tab to
703  * rta_set_recursive_next_hop()), because its routes reference hostentries
704  * (through rta) related to the governing table. When all such routes are
705  * removed, rtas are immediately removed achieving zero uc. Then the 'source'
706  * table lock could be immediately released, although hostentries may still
707  * exist - they will be freed together with the 'source' table.
708  */
709 
rt_lock_hostentry(struct hostentry * he)710 static inline void rt_lock_hostentry(struct hostentry *he) { if (he) he->uc++; }
rt_unlock_hostentry(struct hostentry * he)711 static inline void rt_unlock_hostentry(struct hostentry *he) { if (he) he->uc--; }
712 
713 /*
714  *	Default protocol preferences
715  */
716 
717 #define DEF_PREF_DIRECT		240	/* Directly connected */
718 #define DEF_PREF_STATIC		200	/* Static route */
719 #define DEF_PREF_OSPF		150	/* OSPF intra-area, inter-area and type 1 external routes */
720 #define DEF_PREF_BABEL		130	/* Babel */
721 #define DEF_PREF_RIP		120	/* RIP */
722 #define DEF_PREF_BGP		100	/* BGP */
723 #define DEF_PREF_RPKI		100	/* RPKI */
724 #define DEF_PREF_INHERITED	10	/* Routes inherited from other routing daemons */
725 
726 /*
727  *	Route Origin Authorization
728  */
729 
730 #define ROA_UNKNOWN	0
731 #define ROA_VALID	1
732 #define ROA_INVALID	2
733 
734 #endif
735