]>
Commit | Line | Data |
---|---|---|
62aa008a | 1 | /* |
58740ed4 | 2 | * BIRD -- Routing Tables |
62aa008a | 3 | * |
50fe90ed | 4 | * (c) 1998--2000 Martin Mares <mj@ucw.cz> |
62aa008a MM |
5 | * |
6 | * Can be freely distributed and used under the terms of the GNU GPL. | |
7 | */ | |
8 | ||
58740ed4 MM |
9 | /** |
10 | * DOC: Routing tables | |
11 | * | |
12 | * Routing tables are probably the most important structures BIRD uses. They | |
13 | * hold all the information about known networks, the associated routes and | |
14 | * their attributes. | |
15 | * | |
725270cb | 16 | * There are multiple routing tables (a primary one together with any |
58740ed4 MM |
17 | * number of secondary ones if requested by the configuration). Each table |
18 | * is basically a FIB containing entries describing the individual | |
58f7d004 | 19 | * destination networks. For each network (represented by structure &net), |
725270cb MM |
20 | * there is a one-way linked list of route entries (&rte), the first entry |
21 | * on the list being the best one (i.e., the one we currently use | |
58740ed4 MM |
22 | * for routing), the order of the other ones is undetermined. |
23 | * | |
24 | * The &rte contains information specific to the route (preference, protocol | |
25 | * metrics, time of last modification etc.) and a pointer to a &rta structure | |
26 | * (see the route attribute module for a precise explanation) holding the | |
27 | * remaining route attributes which are expected to be shared by multiple | |
28 | * routes in order to conserve memory. | |
29 | */ | |
30 | ||
6b9fa320 | 31 | #undef LOCAL_DEBUG |
1a54b1c6 | 32 | |
62aa008a MM |
33 | #include "nest/bird.h" |
34 | #include "nest/route.h" | |
2326b001 | 35 | #include "nest/protocol.h" |
730f2e2c MM |
36 | #include "nest/cli.h" |
37 | #include "nest/iface.h" | |
2326b001 | 38 | #include "lib/resource.h" |
5996da6a | 39 | #include "lib/event.h" |
730f2e2c | 40 | #include "lib/string.h" |
0e02abfd | 41 | #include "conf/conf.h" |
529c4149 | 42 | #include "filter/filter.h" |
221135d6 | 43 | #include "lib/string.h" |
10af3676 | 44 | #include "lib/alloca.h" |
7d875e09 | 45 | |
acb60628 OZ |
46 | pool *rt_table_pool; |
47 | ||
2326b001 | 48 | static slab *rte_slab; |
e2dc2f30 | 49 | static linpool *rte_update_pool; |
2326b001 | 50 | |
0e02abfd | 51 | static list routing_tables; |
5996da6a | 52 | |
6887f409 | 53 | static byte *rt_format_via(rte *e); |
cfe34a31 OZ |
54 | static void rt_free_hostcache(rtable *tab); |
55 | static void rt_notify_hostcache(rtable *tab, net *net); | |
56 | static void rt_update_hostcache(rtable *tab); | |
57 | static void rt_next_hop_update(rtable *tab); | |
0c791f87 | 58 | static inline int rt_prune_table(rtable *tab); |
cfe34a31 | 59 | static inline void rt_schedule_gc(rtable *tab); |
0c791f87 OZ |
60 | static inline void rt_schedule_prune(rtable *tab); |
61 | ||
cfd46ee4 | 62 | |
094d2bdb OZ |
63 | static inline struct ea_list * |
64 | make_tmp_attrs(struct rte *rt, struct linpool *pool) | |
65 | { | |
66 | struct ea_list *(*mta)(struct rte *rt, struct linpool *pool); | |
67 | mta = rt->attrs->src->proto->make_tmp_attrs; | |
68 | return mta ? mta(rt, rte_update_pool) : NULL; | |
69 | } | |
70 | ||
d1e146f2 OZ |
71 | /* Like fib_route(), but skips empty net entries */ |
72 | static net * | |
73 | net_route(rtable *tab, ip_addr a, int len) | |
74 | { | |
75 | ip_addr a0; | |
76 | net *n; | |
77 | ||
78 | while (len >= 0) | |
79 | { | |
80 | a0 = ipa_and(a, ipa_mkmask(len)); | |
81 | n = fib_find(&tab->fib, &a0, len); | |
cf98be7b | 82 | if (n && rte_is_valid(n->routes)) |
d1e146f2 OZ |
83 | return n; |
84 | len--; | |
85 | } | |
86 | return NULL; | |
87 | } | |
88 | ||
5996da6a | 89 | static void |
2326b001 MM |
90 | rte_init(struct fib_node *N) |
91 | { | |
92 | net *n = (net *) N; | |
93 | ||
4c45595e | 94 | N->flags = 0; |
2326b001 MM |
95 | n->routes = NULL; |
96 | } | |
97 | ||
58740ed4 MM |
98 | /** |
99 | * rte_find - find a route | |
100 | * @net: network node | |
094d2bdb | 101 | * @src: route source |
58740ed4 MM |
102 | * |
103 | * The rte_find() function returns a route for destination @net | |
094d2bdb | 104 | * which is from route source @src. |
58740ed4 | 105 | */ |
2326b001 | 106 | rte * |
094d2bdb | 107 | rte_find(net *net, struct rte_src *src) |
2326b001 MM |
108 | { |
109 | rte *e = net->routes; | |
110 | ||
094d2bdb | 111 | while (e && e->attrs->src != src) |
2326b001 MM |
112 | e = e->next; |
113 | return e; | |
114 | } | |
115 | ||
58740ed4 MM |
116 | /** |
117 | * rte_get_temp - get a temporary &rte | |
3ce8c610 | 118 | * @a: attributes to assign to the new route (a &rta; in case it's |
2e9b2421 | 119 | * un-cached, rte_update() will create a cached copy automatically) |
58740ed4 MM |
120 | * |
121 | * Create a temporary &rte and bind it with the attributes @a. | |
122 | * Also set route preference to the default preference set for | |
123 | * the protocol. | |
124 | */ | |
2326b001 MM |
125 | rte * |
126 | rte_get_temp(rta *a) | |
127 | { | |
128 | rte *e = sl_alloc(rte_slab); | |
129 | ||
130 | e->attrs = a; | |
0cdbd397 | 131 | e->flags = 0; |
094d2bdb | 132 | e->pref = a->src->proto->preference; |
2326b001 MM |
133 | return e; |
134 | } | |
135 | ||
e2dc2f30 MM |
136 | rte * |
137 | rte_do_cow(rte *r) | |
138 | { | |
139 | rte *e = sl_alloc(rte_slab); | |
140 | ||
141 | memcpy(e, r, sizeof(rte)); | |
142 | e->attrs = rta_clone(r->attrs); | |
143 | e->flags = 0; | |
144 | return e; | |
145 | } | |
146 | ||
8d9eef17 OZ |
147 | /** |
148 | * rte_cow_rta - get a private writable copy of &rte with writable &rta | |
149 | * @r: a route entry to be copied | |
150 | * @lp: a linpool from which to allocate &rta | |
151 | * | |
152 | * rte_cow_rta() takes a &rte and prepares it and associated &rta for | |
153 | * modification. There are three possibilities: First, both &rte and &rta are | |
154 | * private copies, in that case they are returned unchanged. Second, &rte is | |
155 | * private copy, but &rta is cached, in that case &rta is duplicated using | |
156 | * rta_do_cow(). Third, both &rte is shared and &rta is cached, in that case | |
157 | * both structures are duplicated by rte_do_cow() and rta_do_cow(). | |
158 | * | |
159 | * Note that in the second case, cached &rta loses one reference, while private | |
160 | * copy created by rta_do_cow() is a shallow copy sharing indirect data (eattrs, | |
161 | * nexthops, ...) with it. To work properly, original shared &rta should have | |
162 | * another reference during the life of created private copy. | |
163 | * | |
164 | * Result: a pointer to the new writable &rte with writable &rta. | |
165 | */ | |
166 | rte * | |
167 | rte_cow_rta(rte *r, linpool *lp) | |
168 | { | |
169 | if (!rta_is_cached(r->attrs)) | |
170 | return r; | |
171 | ||
172 | rte *e = rte_cow(r); | |
173 | rta *a = rta_do_cow(r->attrs, lp); | |
174 | rta_free(e->attrs); | |
175 | e->attrs = a; | |
176 | return e; | |
177 | } | |
178 | ||
2326b001 MM |
179 | static int /* Actually better or at least as good as */ |
180 | rte_better(rte *new, rte *old) | |
181 | { | |
d9f330c5 MM |
182 | int (*better)(rte *, rte *); |
183 | ||
cf98be7b | 184 | if (!rte_is_valid(old)) |
2326b001 | 185 | return 1; |
cf98be7b OZ |
186 | if (!rte_is_valid(new)) |
187 | return 0; | |
188 | ||
2326b001 MM |
189 | if (new->pref > old->pref) |
190 | return 1; | |
191 | if (new->pref < old->pref) | |
192 | return 0; | |
094d2bdb | 193 | if (new->attrs->src->proto->proto != old->attrs->src->proto->proto) |
4c1b4e1a MM |
194 | { |
195 | /* | |
196 | * If the user has configured protocol preferences, so that two different protocols | |
197 | * have the same preference, try to break the tie by comparing addresses. Not too | |
198 | * useful, but keeps the ordering of routes unambiguous. | |
199 | */ | |
094d2bdb | 200 | return new->attrs->src->proto->proto > old->attrs->src->proto->proto; |
4c1b4e1a | 201 | } |
094d2bdb | 202 | if (better = new->attrs->src->proto->rte_better) |
d9f330c5 MM |
203 | return better(new, old); |
204 | return 0; | |
2326b001 MM |
205 | } |
206 | ||
8d9eef17 OZ |
207 | static int |
208 | rte_mergable(rte *pri, rte *sec) | |
209 | { | |
210 | int (*mergable)(rte *, rte *); | |
211 | ||
212 | if (!rte_is_valid(pri) || !rte_is_valid(sec)) | |
213 | return 0; | |
214 | ||
215 | if (pri->pref != sec->pref) | |
216 | return 0; | |
217 | ||
218 | if (pri->attrs->src->proto->proto != sec->attrs->src->proto->proto) | |
219 | return 0; | |
220 | ||
221 | if (mergable = pri->attrs->src->proto->rte_mergable) | |
222 | return mergable(pri, sec); | |
223 | ||
224 | return 0; | |
225 | } | |
226 | ||
cfd46ee4 MM |
227 | static void |
228 | rte_trace(struct proto *p, rte *e, int dir, char *msg) | |
229 | { | |
6887f409 | 230 | log(L_TRACE "%s %c %s %I/%d %s", p->name, dir, msg, e->net->n.prefix, e->net->n.pxlen, rt_format_via(e)); |
cfd46ee4 MM |
231 | } |
232 | ||
233 | static inline void | |
ae80a2de | 234 | rte_trace_in(uint flag, struct proto *p, rte *e, char *msg) |
cfd46ee4 MM |
235 | { |
236 | if (p->debug & flag) | |
b0a47440 | 237 | rte_trace(p, e, '>', msg); |
cfd46ee4 MM |
238 | } |
239 | ||
240 | static inline void | |
ae80a2de | 241 | rte_trace_out(uint flag, struct proto *p, rte *e, char *msg) |
cfd46ee4 MM |
242 | { |
243 | if (p->debug & flag) | |
b0a47440 | 244 | rte_trace(p, e, '<', msg); |
cfd46ee4 MM |
245 | } |
246 | ||
00a09f3c OZ |
247 | static rte * |
248 | export_filter(struct announce_hook *ah, rte *rt0, rte **rt_free, ea_list **tmpa, int silent) | |
529c4149 | 249 | { |
c0adf7e9 OZ |
250 | struct proto *p = ah->proto; |
251 | struct filter *filter = ah->out_filter; | |
252 | struct proto_stats *stats = ah->stats; | |
00a09f3c OZ |
253 | ea_list *tmpb = NULL; |
254 | rte *rt; | |
255 | int v; | |
c0adf7e9 | 256 | |
00a09f3c OZ |
257 | rt = rt0; |
258 | *rt_free = NULL; | |
7de45ba4 | 259 | |
00a09f3c | 260 | if (!tmpa) |
db027a41 OZ |
261 | tmpa = &tmpb; |
262 | ||
263 | *tmpa = make_tmp_attrs(rt, rte_update_pool); | |
925fe2d3 | 264 | |
00a09f3c OZ |
265 | v = p->import_control ? p->import_control(p, &rt, tmpa, rte_update_pool) : 0; |
266 | if (v < 0) | |
267 | { | |
268 | if (silent) | |
269 | goto reject; | |
11361a10 | 270 | |
00a09f3c | 271 | stats->exp_updates_rejected++; |
36da2857 OZ |
272 | if (v == RIC_REJECT) |
273 | rte_trace_out(D_FILTERS, p, rt, "rejected by protocol"); | |
00a09f3c OZ |
274 | goto reject; |
275 | } | |
276 | if (v > 0) | |
e2dc2f30 | 277 | { |
00a09f3c OZ |
278 | if (!silent) |
279 | rte_trace_out(D_FILTERS, p, rt, "forced accept by protocol"); | |
280 | goto accept; | |
e2dc2f30 | 281 | } |
925fe2d3 | 282 | |
00a09f3c OZ |
283 | v = filter && ((filter == FILTER_REJECT) || |
284 | (f_run(filter, &rt, tmpa, rte_update_pool, FF_FORCE_TMPATTR) > F_ACCEPT)); | |
285 | if (v) | |
286 | { | |
287 | if (silent) | |
288 | goto reject; | |
289 | ||
290 | stats->exp_updates_filtered++; | |
291 | rte_trace_out(D_FILTERS, p, rt, "filtered out"); | |
292 | goto reject; | |
e2dc2f30 | 293 | } |
925fe2d3 | 294 | |
00a09f3c OZ |
295 | accept: |
296 | if (rt != rt0) | |
297 | *rt_free = rt; | |
298 | return rt; | |
299 | ||
300 | reject: | |
301 | /* Discard temporary rte */ | |
302 | if (rt != rt0) | |
303 | rte_free(rt); | |
304 | return NULL; | |
305 | } | |
306 | ||
307 | static void | |
308 | do_rt_notify(struct announce_hook *ah, net *net, rte *new, rte *old, ea_list *tmpa, int refeed) | |
309 | { | |
310 | struct proto *p = ah->proto; | |
311 | struct proto_stats *stats = ah->stats; | |
925fe2d3 | 312 | |
abced4a9 | 313 | |
ab758e4f | 314 | /* |
abced4a9 OZ |
315 | * First, apply export limit. |
316 | * | |
ab758e4f OZ |
317 | * Export route limits has several problems. Because exp_routes |
318 | * counter is reset before refeed, we don't really know whether | |
abced4a9 | 319 | * limit is breached and whether the update is new or not. Therefore |
ab758e4f OZ |
320 | * the number of really exported routes may exceed the limit |
321 | * temporarily (routes exported before and new routes in refeed). | |
322 | * | |
323 | * Minor advantage is that if the limit is decreased and refeed is | |
324 | * requested, the number of exported routes really decrease. | |
325 | * | |
326 | * Second problem is that with export limits, we don't know whether | |
327 | * old was really exported (it might be blocked by limit). When a | |
328 | * withdraw is exported, we announce it even when the previous | |
329 | * update was blocked. This is not a big issue, but the same problem | |
330 | * is in updating exp_routes counter. Therefore, to be consistent in | |
331 | * increases and decreases of exp_routes, we count exported routes | |
332 | * regardless of blocking by limits. | |
333 | * | |
334 | * Similar problem is in handling updates - when a new route is | |
335 | * received and blocking is active, the route would be blocked, but | |
336 | * when an update for the route will be received later, the update | |
337 | * would be propagated (as old != NULL). Therefore, we have to block | |
338 | * also non-new updates (contrary to import blocking). | |
339 | */ | |
925fe2d3 | 340 | |
d9b77cc2 | 341 | struct proto_limit *l = ah->out_limit; |
ab758e4f | 342 | if (l && new) |
d9b77cc2 | 343 | { |
ab758e4f | 344 | if ((!old || refeed) && (stats->exp_routes >= l->limit)) |
b662290f | 345 | proto_notify_limit(ah, l, PLD_OUT, stats->exp_routes); |
d9b77cc2 OZ |
346 | |
347 | if (l->state == PLS_BLOCKED) | |
348 | { | |
ab758e4f | 349 | stats->exp_routes++; /* see note above */ |
d9b77cc2 OZ |
350 | stats->exp_updates_rejected++; |
351 | rte_trace_out(D_FILTERS, p, new, "rejected [limit]"); | |
ab758e4f | 352 | new = NULL; |
abced4a9 OZ |
353 | |
354 | if (!old) | |
355 | return; | |
d9b77cc2 OZ |
356 | } |
357 | } | |
358 | ||
ab758e4f | 359 | |
925fe2d3 | 360 | if (new) |
9db74169 | 361 | stats->exp_updates_accepted++; |
925fe2d3 | 362 | else |
9db74169 | 363 | stats->exp_withdraws_accepted++; |
925fe2d3 | 364 | |
8a7fb885 OZ |
365 | /* Hack: We do not decrease exp_routes during refeed, we instead |
366 | reset exp_routes at the start of refeed. */ | |
925fe2d3 | 367 | if (new) |
9db74169 | 368 | stats->exp_routes++; |
8a7fb885 | 369 | if (old && !refeed) |
9db74169 | 370 | stats->exp_routes--; |
925fe2d3 | 371 | |
cfd46ee4 MM |
372 | if (p->debug & D_ROUTES) |
373 | { | |
374 | if (new && old) | |
375 | rte_trace_out(D_ROUTES, p, new, "replaced"); | |
376 | else if (new) | |
377 | rte_trace_out(D_ROUTES, p, new, "added"); | |
349e21bb | 378 | else if (old) |
cfd46ee4 MM |
379 | rte_trace_out(D_ROUTES, p, old, "removed"); |
380 | } | |
08f0290a | 381 | if (!new) |
c0adf7e9 | 382 | p->rt_notify(p, ah->table, net, NULL, old, NULL); |
08f0290a MM |
383 | else if (tmpa) |
384 | { | |
2f711231 MM |
385 | ea_list *t = tmpa; |
386 | while (t->next) | |
387 | t = t->next; | |
388 | t->next = new->attrs->eattrs; | |
c0adf7e9 | 389 | p->rt_notify(p, ah->table, net, new, old, tmpa); |
2f711231 | 390 | t->next = NULL; |
08f0290a MM |
391 | } |
392 | else | |
c0adf7e9 | 393 | p->rt_notify(p, ah->table, net, new, old, new->attrs->eattrs); |
00a09f3c OZ |
394 | } |
395 | ||
00a09f3c | 396 | static void |
db027a41 | 397 | rt_notify_basic(struct announce_hook *ah, net *net, rte *new0, rte *old0, int refeed) |
00a09f3c | 398 | { |
86f567e1 | 399 | struct proto *p = ah->proto; |
00a09f3c OZ |
400 | struct proto_stats *stats = ah->stats; |
401 | ||
86f567e1 OZ |
402 | rte *new = new0; |
403 | rte *old = old0; | |
00a09f3c OZ |
404 | rte *new_free = NULL; |
405 | rte *old_free = NULL; | |
db027a41 | 406 | ea_list *tmpa = NULL; |
00a09f3c OZ |
407 | |
408 | if (new) | |
409 | stats->exp_updates_received++; | |
410 | else | |
411 | stats->exp_withdraws_received++; | |
412 | ||
413 | /* | |
414 | * This is a tricky part - we don't know whether route 'old' was | |
415 | * exported to protocol 'p' or was filtered by the export filter. | |
416 | * We try to run the export filter to know this to have a correct | |
417 | * value in 'old' argument of rte_update (and proper filter value) | |
418 | * | |
419 | * FIXME - this is broken because 'configure soft' may change | |
420 | * filters but keep routes. Refeed is expected to be called after | |
421 | * change of the filters and with old == new, therefore we do not | |
86f567e1 | 422 | * even try to run the filter on an old route, This may lead to |
00a09f3c OZ |
423 | * 'spurious withdraws' but ensure that there are no 'missing |
424 | * withdraws'. | |
425 | * | |
426 | * This is not completely safe as there is a window between | |
427 | * reconfiguration and the end of refeed - if a newly filtered | |
428 | * route disappears during this period, proper withdraw is not | |
429 | * sent (because old would be also filtered) and the route is | |
430 | * not refeeded (because it disappeared before that). | |
431 | */ | |
432 | ||
433 | if (new) | |
434 | new = export_filter(ah, new, &new_free, &tmpa, 0); | |
435 | ||
436 | if (old && !refeed) | |
437 | old = export_filter(ah, old, &old_free, NULL, 1); | |
438 | ||
00a09f3c | 439 | if (!new && !old) |
86f567e1 OZ |
440 | { |
441 | /* | |
442 | * As mentioned above, 'old' value may be incorrect in some race conditions. | |
443 | * We generally ignore it with the exception of withdraw to pipe protocol. | |
444 | * In that case we rather propagate unfiltered withdraws regardless of | |
445 | * export filters to ensure that when a protocol is flushed, its routes are | |
446 | * removed from all tables. Possible spurious unfiltered withdraws are not | |
447 | * problem here as they are ignored if there is no corresponding route at | |
448 | * the other end of the pipe. We directly call rt_notify() hook instead of | |
449 | * do_rt_notify() to avoid logging and stat counters. | |
450 | */ | |
451 | ||
452 | #ifdef CONFIG_PIPE | |
453 | if ((p->proto == &proto_pipe) && !new0 && (p != old0->sender->proto)) | |
454 | p->rt_notify(p, ah->table, net, NULL, old0, NULL); | |
455 | #endif | |
456 | ||
00a09f3c | 457 | return; |
86f567e1 | 458 | } |
00a09f3c OZ |
459 | |
460 | do_rt_notify(ah, net, new, old, tmpa, refeed); | |
461 | ||
462 | /* Discard temporary rte's */ | |
463 | if (new_free) | |
464 | rte_free(new_free); | |
465 | if (old_free) | |
466 | rte_free(old_free); | |
467 | } | |
468 | ||
469 | static void | |
db027a41 | 470 | rt_notify_accepted(struct announce_hook *ah, net *net, rte *new_changed, rte *old_changed, rte *before_old, int feed) |
00a09f3c OZ |
471 | { |
472 | // struct proto *p = ah->proto; | |
473 | struct proto_stats *stats = ah->stats; | |
474 | ||
db027a41 | 475 | rte *r; |
00a09f3c OZ |
476 | rte *new_best = NULL; |
477 | rte *old_best = NULL; | |
478 | rte *new_free = NULL; | |
479 | rte *old_free = NULL; | |
db027a41 | 480 | ea_list *tmpa = NULL; |
00a09f3c | 481 | |
cf98be7b OZ |
482 | /* Used to track whether we met old_changed position. If before_old is NULL |
483 | old_changed was the first and we met it implicitly before current best route. */ | |
484 | int old_meet = old_changed && !before_old; | |
485 | ||
486 | /* Note that before_old is either NULL or valid (not rejected) route. | |
487 | If old_changed is valid, before_old have to be too. If old changed route | |
488 | was not valid, caller must use NULL for both old_changed and before_old. */ | |
00a09f3c OZ |
489 | |
490 | if (new_changed) | |
491 | stats->exp_updates_received++; | |
492 | else | |
493 | stats->exp_withdraws_received++; | |
494 | ||
495 | /* First, find the new_best route - first accepted by filters */ | |
cf98be7b | 496 | for (r=net->routes; rte_is_valid(r); r=r->next) |
00a09f3c OZ |
497 | { |
498 | if (new_best = export_filter(ah, r, &new_free, &tmpa, 0)) | |
499 | break; | |
500 | ||
501 | /* Note if we walked around the position of old_changed route */ | |
502 | if (r == before_old) | |
503 | old_meet = 1; | |
504 | } | |
505 | ||
506 | /* | |
507 | * Second, handle the feed case. That means we do not care for | |
508 | * old_best. It is NULL for feed, and the new_best for refeed. | |
509 | * For refeed, there is a hack similar to one in rt_notify_basic() | |
510 | * to ensure withdraws in case of changed filters | |
511 | */ | |
512 | if (feed) | |
513 | { | |
514 | if (feed == 2) /* refeed */ | |
cf98be7b OZ |
515 | old_best = new_best ? new_best : |
516 | (rte_is_valid(net->routes) ? net->routes : NULL); | |
00a09f3c OZ |
517 | else |
518 | old_best = NULL; | |
519 | ||
520 | if (!new_best && !old_best) | |
521 | return; | |
522 | ||
523 | goto found; | |
524 | } | |
525 | ||
526 | /* | |
527 | * Now, we find the old_best route. Generally, it is the same as the | |
528 | * new_best, unless new_best is the same as new_changed or | |
529 | * old_changed is accepted before new_best. | |
530 | * | |
531 | * There are four cases: | |
532 | * | |
533 | * - We would find and accept old_changed before new_best, therefore | |
534 | * old_changed is old_best. In remaining cases we suppose this | |
535 | * is not true. | |
536 | * | |
537 | * - We found no new_best, therefore there is also no old_best and | |
538 | * we ignore this withdraw. | |
539 | * | |
540 | * - We found new_best different than new_changed, therefore | |
541 | * old_best is the same as new_best and we ignore this update. | |
542 | * | |
543 | * - We found new_best the same as new_changed, therefore it cannot | |
544 | * be old_best and we have to continue search for old_best. | |
545 | */ | |
546 | ||
547 | /* First case */ | |
548 | if (old_meet) | |
549 | if (old_best = export_filter(ah, old_changed, &old_free, NULL, 1)) | |
550 | goto found; | |
551 | ||
552 | /* Second case */ | |
553 | if (!new_best) | |
554 | return; | |
d9b77cc2 | 555 | |
26822d8f | 556 | /* Third case, we use r instead of new_best, because export_filter() could change it */ |
00a09f3c OZ |
557 | if (r != new_changed) |
558 | { | |
559 | if (new_free) | |
560 | rte_free(new_free); | |
561 | return; | |
562 | } | |
563 | ||
564 | /* Fourth case */ | |
cf98be7b | 565 | for (r=r->next; rte_is_valid(r); r=r->next) |
00a09f3c OZ |
566 | { |
567 | if (old_best = export_filter(ah, r, &old_free, NULL, 1)) | |
568 | goto found; | |
569 | ||
570 | if (r == before_old) | |
571 | if (old_best = export_filter(ah, old_changed, &old_free, NULL, 1)) | |
572 | goto found; | |
573 | } | |
574 | ||
575 | /* Implicitly, old_best is NULL and new_best is non-NULL */ | |
576 | ||
577 | found: | |
578 | do_rt_notify(ah, net, new_best, old_best, tmpa, (feed == 2)); | |
579 | ||
580 | /* Discard temporary rte's */ | |
581 | if (new_free) | |
582 | rte_free(new_free); | |
583 | if (old_free) | |
584 | rte_free(old_free); | |
529c4149 MM |
585 | } |
586 | ||
8d9eef17 OZ |
587 | |
588 | static struct mpnh * | |
589 | mpnh_merge_rta(struct mpnh *nhs, rta *a, int max) | |
590 | { | |
591 | struct mpnh nh = { .gw = a->gw, .iface = a->iface }; | |
592 | struct mpnh *nh2 = (a->dest == RTD_MULTIPATH) ? a->nexthops : &nh; | |
593 | return mpnh_merge(nhs, nh2, 1, 0, max, rte_update_pool); | |
594 | } | |
595 | ||
596 | rte * | |
597 | rt_export_merged(struct announce_hook *ah, net *net, rte **rt_free, ea_list **tmpa, int silent) | |
598 | { | |
599 | // struct proto *p = ah->proto; | |
600 | struct mpnh *nhs = NULL; | |
601 | rte *best0, *best, *rt0, *rt, *tmp; | |
602 | ||
603 | best0 = net->routes; | |
604 | *rt_free = NULL; | |
605 | ||
606 | if (!rte_is_valid(best0)) | |
607 | return NULL; | |
608 | ||
609 | best = export_filter(ah, best0, rt_free, tmpa, silent); | |
610 | ||
611 | if (!best || !rte_is_reachable(best)) | |
612 | return best; | |
613 | ||
614 | for (rt0 = best0->next; rt0; rt0 = rt0->next) | |
615 | { | |
616 | if (!rte_mergable(best0, rt0)) | |
617 | continue; | |
618 | ||
619 | rt = export_filter(ah, rt0, &tmp, NULL, 1); | |
620 | ||
621 | if (!rt) | |
622 | continue; | |
623 | ||
624 | if (rte_is_reachable(rt)) | |
625 | nhs = mpnh_merge_rta(nhs, rt->attrs, ah->proto->merge_limit); | |
626 | ||
627 | if (tmp) | |
628 | rte_free(tmp); | |
629 | } | |
630 | ||
631 | if (nhs) | |
632 | { | |
633 | nhs = mpnh_merge_rta(nhs, best->attrs, ah->proto->merge_limit); | |
634 | ||
635 | if (nhs->next) | |
636 | { | |
637 | best = rte_cow_rta(best, rte_update_pool); | |
638 | best->attrs->dest = RTD_MULTIPATH; | |
639 | best->attrs->nexthops = nhs; | |
640 | } | |
641 | } | |
642 | ||
643 | if (best != best0) | |
644 | *rt_free = best; | |
645 | ||
646 | return best; | |
647 | } | |
648 | ||
649 | ||
650 | static void | |
651 | rt_notify_merged(struct announce_hook *ah, net *net, rte *new_changed, rte *old_changed, | |
652 | rte *new_best, rte*old_best, int refeed) | |
653 | { | |
654 | // struct proto *p = ah->proto; | |
655 | ||
656 | rte *new_best_free = NULL; | |
657 | rte *old_best_free = NULL; | |
658 | rte *new_changed_free = NULL; | |
659 | rte *old_changed_free = NULL; | |
660 | ea_list *tmpa = NULL; | |
661 | ||
662 | /* We assume that all rte arguments are either NULL or rte_is_valid() */ | |
663 | ||
664 | /* This check should be done by the caller */ | |
665 | if (!new_best && !old_best) | |
666 | return; | |
667 | ||
668 | /* Check whether the change is relevant to the merged route */ | |
669 | if ((new_best == old_best) && !refeed) | |
670 | { | |
671 | new_changed = rte_mergable(new_best, new_changed) ? | |
672 | export_filter(ah, new_changed, &new_changed_free, NULL, 1) : NULL; | |
673 | ||
674 | old_changed = rte_mergable(old_best, old_changed) ? | |
675 | export_filter(ah, old_changed, &old_changed_free, NULL, 1) : NULL; | |
676 | ||
677 | if (!new_changed && !old_changed) | |
678 | return; | |
679 | } | |
680 | ||
681 | if (new_best) | |
682 | ah->stats->exp_updates_received++; | |
683 | else | |
684 | ah->stats->exp_withdraws_received++; | |
685 | ||
686 | /* Prepare new merged route */ | |
687 | if (new_best) | |
688 | new_best = rt_export_merged(ah, net, &new_best_free, &tmpa, 0); | |
689 | ||
690 | /* Prepare old merged route (without proper merged next hops) */ | |
691 | /* There are some issues with running filter on old route - see rt_notify_basic() */ | |
692 | if (old_best && !refeed) | |
693 | old_best = export_filter(ah, old_best, &old_best_free, NULL, 1); | |
694 | ||
695 | if (new_best || old_best) | |
696 | do_rt_notify(ah, net, new_best, old_best, tmpa, refeed); | |
697 | ||
698 | /* Discard temporary rte's */ | |
699 | if (new_best_free) | |
700 | rte_free(new_best_free); | |
701 | if (old_best_free) | |
702 | rte_free(old_best_free); | |
703 | if (new_changed_free) | |
704 | rte_free(new_changed_free); | |
705 | if (old_changed_free) | |
706 | rte_free(old_changed_free); | |
707 | } | |
708 | ||
709 | ||
9a8f20fc MM |
710 | /** |
711 | * rte_announce - announce a routing table change | |
712 | * @tab: table the route has been added to | |
23ac9e9a | 713 | * @type: type of route announcement (RA_OPTIMAL or RA_ANY) |
9a8f20fc MM |
714 | * @net: network in question |
715 | * @new: the new route to be announced | |
23ac9e9a | 716 | * @old: the previous route for the same network |
8e433d6a PT |
717 | * @new_best: the new best route for the same network |
718 | * @old_best: the previous best route for the same network | |
719 | * @before_old: The previous route before @old for the same network. | |
720 | * If @before_old is NULL @old was the first. | |
9a8f20fc MM |
721 | * |
722 | * This function gets a routing table update and announces it | |
f98e2915 OZ |
723 | * to all protocols that acccepts given type of route announcement |
724 | * and are connected to the same table by their announcement hooks. | |
9a8f20fc | 725 | * |
8e433d6a | 726 | * Route announcement of type %RA_OPTIMAL si generated when optimal |
f98e2915 OZ |
727 | * route (in routing table @tab) changes. In that case @old stores the |
728 | * old optimal route. | |
23ac9e9a | 729 | * |
8e433d6a | 730 | * Route announcement of type %RA_ANY si generated when any route (in |
f98e2915 OZ |
731 | * routing table @tab) changes In that case @old stores the old route |
732 | * from the same protocol. | |
733 | * | |
734 | * For each appropriate protocol, we first call its import_control() | |
735 | * hook which performs basic checks on the route (each protocol has a | |
736 | * right to veto or force accept of the route before any filter is | |
737 | * asked) and adds default values of attributes specific to the new | |
738 | * protocol (metrics, tags etc.). Then it consults the protocol's | |
739 | * export filter and if it accepts the route, the rt_notify() hook of | |
740 | * the protocol gets called. | |
9a8f20fc | 741 | */ |
e2dc2f30 | 742 | static void |
8d9eef17 OZ |
743 | rte_announce(rtable *tab, unsigned type, net *net, rte *new, rte *old, |
744 | rte *new_best, rte *old_best, rte *before_old) | |
2326b001 | 745 | { |
8d9eef17 OZ |
746 | if (!rte_is_valid(new)) |
747 | new = NULL; | |
748 | ||
cf98be7b OZ |
749 | if (!rte_is_valid(old)) |
750 | old = before_old = NULL; | |
751 | ||
8d9eef17 OZ |
752 | if (!rte_is_valid(new_best)) |
753 | new_best = NULL; | |
754 | ||
755 | if (!rte_is_valid(old_best)) | |
756 | old_best = NULL; | |
cf98be7b OZ |
757 | |
758 | if (!old && !new) | |
759 | return; | |
2326b001 | 760 | |
925fe2d3 OZ |
761 | if (type == RA_OPTIMAL) |
762 | { | |
763 | if (new) | |
094d2bdb | 764 | new->attrs->src->proto->stats.pref_routes++; |
925fe2d3 | 765 | if (old) |
094d2bdb | 766 | old->attrs->src->proto->stats.pref_routes--; |
cfe34a31 OZ |
767 | |
768 | if (tab->hostcache) | |
769 | rt_notify_hostcache(tab, net); | |
925fe2d3 OZ |
770 | } |
771 | ||
cf98be7b | 772 | struct announce_hook *a; |
0e02abfd | 773 | WALK_LIST(a, tab->hooks) |
0a2e9d9f | 774 | { |
0c791f87 | 775 | ASSERT(a->proto->export_state != ES_DOWN); |
23ac9e9a | 776 | if (a->proto->accept_ra_types == type) |
00a09f3c | 777 | if (type == RA_ACCEPTED) |
db027a41 | 778 | rt_notify_accepted(a, net, new, old, before_old, 0); |
8d9eef17 OZ |
779 | else if (type == RA_MERGED) |
780 | rt_notify_merged(a, net, new, old, new_best, old_best, 0); | |
00a09f3c | 781 | else |
db027a41 | 782 | rt_notify_basic(a, net, new, old, 0); |
0a2e9d9f | 783 | } |
2326b001 MM |
784 | } |
785 | ||
421838ff MM |
786 | static inline int |
787 | rte_validate(rte *e) | |
788 | { | |
789 | int c; | |
790 | net *n = e->net; | |
791 | ||
852b7062 | 792 | if ((n->n.pxlen > BITS_PER_IP_ADDRESS) || !ip_is_prefix(n->n.prefix,n->n.pxlen)) |
cfd46ee4 | 793 | { |
ab164971 | 794 | log(L_WARN "Ignoring bogus prefix %I/%d received via %s", |
c0adf7e9 | 795 | n->n.prefix, n->n.pxlen, e->sender->proto->name); |
cfd46ee4 MM |
796 | return 0; |
797 | } | |
ff2857b0 OZ |
798 | |
799 | c = ipa_classify_net(n->n.prefix); | |
800 | if ((c < 0) || !(c & IADDR_HOST) || ((c & IADDR_SCOPE_MASK) <= SCOPE_LINK)) | |
421838ff | 801 | { |
ff2857b0 | 802 | log(L_WARN "Ignoring bogus route %I/%d received via %s", |
c0adf7e9 | 803 | n->n.prefix, n->n.pxlen, e->sender->proto->name); |
ff2857b0 | 804 | return 0; |
421838ff | 805 | } |
ff2857b0 | 806 | |
421838ff MM |
807 | return 1; |
808 | } | |
809 | ||
58740ed4 MM |
810 | /** |
811 | * rte_free - delete a &rte | |
812 | * @e: &rte to be deleted | |
813 | * | |
814 | * rte_free() deletes the given &rte from the routing table it's linked to. | |
815 | */ | |
04925e90 | 816 | void |
2326b001 | 817 | rte_free(rte *e) |
04925e90 | 818 | { |
094d2bdb | 819 | if (rta_is_cached(e->attrs)) |
04925e90 MM |
820 | rta_free(e->attrs); |
821 | sl_free(rte_slab, e); | |
822 | } | |
823 | ||
824 | static inline void | |
825 | rte_free_quick(rte *e) | |
2326b001 MM |
826 | { |
827 | rta_free(e->attrs); | |
828 | sl_free(rte_slab, e); | |
829 | } | |
830 | ||
67be5b23 MM |
831 | static int |
832 | rte_same(rte *x, rte *y) | |
833 | { | |
834 | return | |
835 | x->attrs == y->attrs && | |
836 | x->flags == y->flags && | |
837 | x->pflags == y->pflags && | |
838 | x->pref == y->pref && | |
094d2bdb | 839 | (!x->attrs->src->proto->rte_same || x->attrs->src->proto->rte_same(x, y)); |
67be5b23 MM |
840 | } |
841 | ||
70577529 OZ |
842 | static inline int rte_is_ok(rte *e) { return e && !rte_is_filtered(e); } |
843 | ||
e2dc2f30 | 844 | static void |
db027a41 | 845 | rte_recalculate(struct announce_hook *ah, net *net, rte *new, struct rte_src *src) |
2326b001 | 846 | { |
c0adf7e9 OZ |
847 | struct proto *p = ah->proto; |
848 | struct rtable *table = ah->table; | |
849 | struct proto_stats *stats = ah->stats; | |
1123e707 | 850 | static struct tbf rl_pipe = TBF_DEFAULT_LOG_LIMITS; |
00a09f3c | 851 | rte *before_old = NULL; |
2326b001 MM |
852 | rte *old_best = net->routes; |
853 | rte *old = NULL; | |
00a09f3c | 854 | rte **k; |
2326b001 MM |
855 | |
856 | k = &net->routes; /* Find and remove original route from the same protocol */ | |
857 | while (old = *k) | |
858 | { | |
094d2bdb | 859 | if (old->attrs->src == src) |
2326b001 | 860 | { |
11787b84 OZ |
861 | /* If there is the same route in the routing table but from |
862 | * a different sender, then there are two paths from the | |
863 | * source protocol to this routing table through transparent | |
864 | * pipes, which is not allowed. | |
865 | * | |
866 | * We log that and ignore the route. If it is withdraw, we | |
867 | * ignore it completely (there might be 'spurious withdraws', | |
868 | * see FIXME in do_rte_announce()) | |
869 | */ | |
c0adf7e9 | 870 | if (old->sender->proto != p) |
11787b84 OZ |
871 | { |
872 | if (new) | |
873 | { | |
548c329c | 874 | log_rl(&rl_pipe, L_ERR "Pipe collision detected when sending %I/%d to table %s", |
11787b84 OZ |
875 | net->n.prefix, net->n.pxlen, table->name); |
876 | rte_free_quick(new); | |
877 | } | |
878 | return; | |
879 | } | |
880 | ||
0b761098 | 881 | if (new && rte_same(old, new)) |
67be5b23 MM |
882 | { |
883 | /* No changes, ignore the new route */ | |
cf98be7b | 884 | |
15550957 | 885 | if (!rte_is_filtered(new)) |
cf98be7b OZ |
886 | { |
887 | stats->imp_updates_ignored++; | |
888 | rte_trace_in(D_ROUTES, p, new, "ignored"); | |
889 | } | |
890 | ||
67be5b23 | 891 | rte_free_quick(new); |
67be5b23 MM |
892 | return; |
893 | } | |
2326b001 MM |
894 | *k = old->next; |
895 | break; | |
896 | } | |
897 | k = &old->next; | |
00a09f3c | 898 | before_old = old; |
2326b001 MM |
899 | } |
900 | ||
00a09f3c OZ |
901 | if (!old) |
902 | before_old = NULL; | |
903 | ||
925fe2d3 OZ |
904 | if (!old && !new) |
905 | { | |
9db74169 | 906 | stats->imp_withdraws_ignored++; |
925fe2d3 OZ |
907 | return; |
908 | } | |
909 | ||
b662290f OZ |
910 | int new_ok = rte_is_ok(new); |
911 | int old_ok = rte_is_ok(old); | |
912 | ||
913 | struct proto_limit *l = ah->rx_limit; | |
7d0a31de | 914 | if (l && !old && new) |
ebecb6f6 | 915 | { |
15550957 | 916 | u32 all_routes = stats->imp_routes + stats->filt_routes; |
cf98be7b OZ |
917 | |
918 | if (all_routes >= l->limit) | |
b662290f | 919 | proto_notify_limit(ah, l, PLD_RX, all_routes); |
7d0a31de OZ |
920 | |
921 | if (l->state == PLS_BLOCKED) | |
922 | { | |
b662290f OZ |
923 | /* In receive limit the situation is simple, old is NULL so |
924 | we just free new and exit like nothing happened */ | |
925 | ||
7d0a31de OZ |
926 | stats->imp_updates_ignored++; |
927 | rte_trace_in(D_FILTERS, p, new, "ignored [limit]"); | |
928 | rte_free_quick(new); | |
929 | return; | |
930 | } | |
ebecb6f6 OZ |
931 | } |
932 | ||
b662290f OZ |
933 | l = ah->in_limit; |
934 | if (l && !old_ok && new_ok) | |
935 | { | |
936 | if (stats->imp_routes >= l->limit) | |
937 | proto_notify_limit(ah, l, PLD_IN, stats->imp_routes); | |
938 | ||
939 | if (l->state == PLS_BLOCKED) | |
940 | { | |
941 | /* In import limit the situation is more complicated. We | |
942 | shouldn't just drop the route, we should handle it like | |
943 | it was filtered. We also have to continue the route | |
944 | processing if old or new is non-NULL, but we should exit | |
945 | if both are NULL as this case is probably assumed to be | |
946 | already handled. */ | |
947 | ||
948 | stats->imp_updates_ignored++; | |
949 | rte_trace_in(D_FILTERS, p, new, "ignored [limit]"); | |
950 | ||
951 | if (ah->in_keep_filtered) | |
952 | new->flags |= REF_FILTERED; | |
953 | else | |
954 | { rte_free_quick(new); new = NULL; } | |
955 | ||
956 | /* Note that old && !new could be possible when | |
957 | ah->in_keep_filtered changed in the recent past. */ | |
958 | ||
959 | if (!old && !new) | |
960 | return; | |
961 | ||
962 | new_ok = 0; | |
963 | goto skip_stats1; | |
964 | } | |
965 | } | |
70577529 OZ |
966 | |
967 | if (new_ok) | |
9db74169 | 968 | stats->imp_updates_accepted++; |
70577529 | 969 | else if (old_ok) |
9db74169 | 970 | stats->imp_withdraws_accepted++; |
70577529 OZ |
971 | else |
972 | stats->imp_withdraws_ignored++; | |
925fe2d3 | 973 | |
b662290f | 974 | skip_stats1: |
925fe2d3 OZ |
975 | |
976 | if (new) | |
15550957 | 977 | rte_is_filtered(new) ? stats->filt_routes++ : stats->imp_routes++; |
925fe2d3 | 978 | if (old) |
15550957 | 979 | rte_is_filtered(old) ? stats->filt_routes-- : stats->imp_routes--; |
925fe2d3 | 980 | |
26822d8f | 981 | if (table->config->sorted) |
2326b001 | 982 | { |
26822d8f OZ |
983 | /* If routes are sorted, just insert new route to appropriate position */ |
984 | if (new) | |
985 | { | |
986 | if (before_old && !rte_better(new, before_old)) | |
987 | k = &before_old->next; | |
988 | else | |
989 | k = &net->routes; | |
c0973621 | 990 | |
26822d8f OZ |
991 | for (; *k; k=&(*k)->next) |
992 | if (rte_better(new, *k)) | |
993 | break; | |
c0973621 | 994 | |
26822d8f OZ |
995 | new->next = *k; |
996 | *k = new; | |
997 | } | |
2326b001 | 998 | } |
26822d8f | 999 | else |
2326b001 | 1000 | { |
26822d8f OZ |
1001 | /* If routes are not sorted, find the best route and move it on |
1002 | the first position. There are several optimized cases. */ | |
1003 | ||
094d2bdb | 1004 | if (src->proto->rte_recalculate && src->proto->rte_recalculate(table, net, new, old, old_best)) |
26822d8f OZ |
1005 | goto do_recalculate; |
1006 | ||
1007 | if (new && rte_better(new, old_best)) | |
2326b001 | 1008 | { |
26822d8f OZ |
1009 | /* The first case - the new route is cleary optimal, |
1010 | we link it at the first position */ | |
1011 | ||
c0973621 OZ |
1012 | new->next = net->routes; |
1013 | net->routes = new; | |
1014 | } | |
26822d8f | 1015 | else if (old == old_best) |
c0973621 | 1016 | { |
26822d8f OZ |
1017 | /* The second case - the old best route disappeared, we add the |
1018 | new route (if we have any) to the list (we don't care about | |
1019 | position) and then we elect the new optimal route and relink | |
1020 | that route at the first position and announce it. New optimal | |
1021 | route might be NULL if there is no more routes */ | |
1022 | ||
1023 | do_recalculate: | |
1024 | /* Add the new route to the list */ | |
1025 | if (new) | |
2326b001 | 1026 | { |
26822d8f OZ |
1027 | new->next = net->routes; |
1028 | net->routes = new; | |
1029 | } | |
1030 | ||
1031 | /* Find a new optimal route (if there is any) */ | |
1032 | if (net->routes) | |
1033 | { | |
1034 | rte **bp = &net->routes; | |
1035 | for (k=&(*bp)->next; *k; k=&(*k)->next) | |
1036 | if (rte_better(*k, *bp)) | |
1037 | bp = k; | |
1038 | ||
1039 | /* And relink it */ | |
1040 | rte *best = *bp; | |
1041 | *bp = best->next; | |
1042 | best->next = net->routes; | |
1043 | net->routes = best; | |
2326b001 | 1044 | } |
2326b001 | 1045 | } |
26822d8f OZ |
1046 | else if (new) |
1047 | { | |
1048 | /* The third case - the new route is not better than the old | |
1049 | best route (therefore old_best != NULL) and the old best | |
1050 | route was not removed (therefore old_best == net->routes). | |
1051 | We just link the new route after the old best route. */ | |
1052 | ||
1053 | ASSERT(net->routes != NULL); | |
1054 | new->next = net->routes->next; | |
1055 | net->routes->next = new; | |
1056 | } | |
1057 | /* The fourth (empty) case - suboptimal route was removed, nothing to do */ | |
2326b001 | 1058 | } |
c0973621 | 1059 | |
26822d8f OZ |
1060 | if (new) |
1061 | new->lastmod = now; | |
1062 | ||
1063 | /* Log the route change */ | |
70577529 | 1064 | if (p->debug & D_ROUTES) |
e8b29bdc | 1065 | { |
70577529 OZ |
1066 | if (new_ok) |
1067 | rte_trace(p, new, '>', new == net->routes ? "added [best]" : "added"); | |
1068 | else if (old_ok) | |
1069 | { | |
1070 | if (old != old_best) | |
1071 | rte_trace(p, old, '>', "removed"); | |
1072 | else if (rte_is_ok(net->routes)) | |
1073 | rte_trace(p, old, '>', "removed [replaced]"); | |
1074 | else | |
1075 | rte_trace(p, old, '>', "removed [sole]"); | |
1076 | } | |
c0973621 OZ |
1077 | } |
1078 | ||
26822d8f | 1079 | /* Propagate the route change */ |
8d9eef17 | 1080 | rte_announce(table, RA_ANY, net, new, old, NULL, NULL, NULL); |
26822d8f | 1081 | if (net->routes != old_best) |
8d9eef17 | 1082 | rte_announce(table, RA_OPTIMAL, net, net->routes, old_best, NULL, NULL, NULL); |
26822d8f | 1083 | if (table->config->sorted) |
8d9eef17 OZ |
1084 | rte_announce(table, RA_ACCEPTED, net, new, old, NULL, NULL, before_old); |
1085 | rte_announce(table, RA_MERGED, net, new, old, net->routes, old_best, NULL); | |
00a09f3c OZ |
1086 | |
1087 | if (!net->routes && | |
1088 | (table->gc_counter++ >= table->config->gc_max_ops) && | |
1089 | (table->gc_time + table->config->gc_min_time <= now)) | |
1090 | rt_schedule_gc(table); | |
1091 | ||
70577529 OZ |
1092 | if (old_ok && p->rte_remove) |
1093 | p->rte_remove(net, old); | |
1094 | if (new_ok && p->rte_insert) | |
1095 | p->rte_insert(net, new); | |
1096 | ||
2326b001 | 1097 | if (old) |
70577529 | 1098 | rte_free_quick(old); |
5b22683d MM |
1099 | } |
1100 | ||
e2dc2f30 MM |
1101 | static int rte_update_nest_cnt; /* Nesting counter to allow recursive updates */ |
1102 | ||
1103 | static inline void | |
1104 | rte_update_lock(void) | |
1105 | { | |
1106 | rte_update_nest_cnt++; | |
1107 | } | |
1108 | ||
1109 | static inline void | |
1110 | rte_update_unlock(void) | |
1111 | { | |
1112 | if (!--rte_update_nest_cnt) | |
1113 | lp_flush(rte_update_pool); | |
1114 | } | |
1115 | ||
fad04c75 OZ |
1116 | static inline void |
1117 | rte_hide_dummy_routes(net *net, rte **dummy) | |
1118 | { | |
1119 | if (net->routes && net->routes->attrs->source == RTS_DUMMY) | |
1120 | { | |
1121 | *dummy = net->routes; | |
1122 | net->routes = (*dummy)->next; | |
1123 | } | |
1124 | } | |
1125 | ||
1126 | static inline void | |
1127 | rte_unhide_dummy_routes(net *net, rte **dummy) | |
1128 | { | |
1129 | if (*dummy) | |
1130 | { | |
1131 | (*dummy)->next = net->routes; | |
1132 | net->routes = *dummy; | |
1133 | } | |
1134 | } | |
1135 | ||
58740ed4 MM |
1136 | /** |
1137 | * rte_update - enter a new update to a routing table | |
1138 | * @table: table to be updated | |
c0adf7e9 | 1139 | * @ah: pointer to table announce hook |
58740ed4 MM |
1140 | * @net: network node |
1141 | * @p: protocol submitting the update | |
f98e2915 | 1142 | * @src: protocol originating the update |
58740ed4 MM |
1143 | * @new: a &rte representing the new route or %NULL for route removal. |
1144 | * | |
1145 | * This function is called by the routing protocols whenever they discover | |
1146 | * a new route or wish to update/remove an existing route. The right announcement | |
2e9b2421 | 1147 | * sequence is to build route attributes first (either un-cached with @aflags set |
58740ed4 MM |
1148 | * to zero or a cached one using rta_lookup(); in this case please note that |
1149 | * you need to increase the use count of the attributes yourself by calling | |
1150 | * rta_clone()), call rte_get_temp() to obtain a temporary &rte, fill in all | |
1151 | * the appropriate data and finally submit the new &rte by calling rte_update(). | |
1152 | * | |
f98e2915 OZ |
1153 | * @src specifies the protocol that originally created the route and the meaning |
1154 | * of protocol-dependent data of @new. If @new is not %NULL, @src have to be the | |
1155 | * same value as @new->attrs->proto. @p specifies the protocol that called | |
1156 | * rte_update(). In most cases it is the same protocol as @src. rte_update() | |
1157 | * stores @p in @new->sender; | |
1158 | * | |
9a8f20fc MM |
1159 | * When rte_update() gets any route, it automatically validates it (checks, |
1160 | * whether the network and next hop address are valid IP addresses and also | |
1161 | * whether a normal routing protocol doesn't try to smuggle a host or link | |
1162 | * scope route to the table), converts all protocol dependent attributes stored | |
1163 | * in the &rte to temporary extended attributes, consults import filters of the | |
1164 | * protocol to see if the route should be accepted and/or its attributes modified, | |
1165 | * stores the temporary attributes back to the &rte. | |
1166 | * | |
1167 | * Now, having a "public" version of the route, we | |
f98e2915 | 1168 | * automatically find any old route defined by the protocol @src |
58740ed4 MM |
1169 | * for network @n, replace it by the new one (or removing it if @new is %NULL), |
1170 | * recalculate the optimal route for this destination and finally broadcast | |
9a8f20fc | 1171 | * the change (if any) to all routing protocols by calling rte_announce(). |
3ce8c610 MM |
1172 | * |
1173 | * All memory used for attribute lists and other temporary allocations is taken | |
1174 | * from a special linear pool @rte_update_pool and freed when rte_update() | |
1175 | * finishes. | |
58740ed4 | 1176 | */ |
23ac9e9a OZ |
1177 | |
1178 | void | |
094d2bdb | 1179 | rte_update2(struct announce_hook *ah, net *net, rte *new, struct rte_src *src) |
e2dc2f30 | 1180 | { |
c0adf7e9 OZ |
1181 | struct proto *p = ah->proto; |
1182 | struct proto_stats *stats = ah->stats; | |
1183 | struct filter *filter = ah->in_filter; | |
e2dc2f30 | 1184 | ea_list *tmpa = NULL; |
fad04c75 | 1185 | rte *dummy = NULL; |
e2dc2f30 MM |
1186 | |
1187 | rte_update_lock(); | |
1188 | if (new) | |
1189 | { | |
c0adf7e9 | 1190 | new->sender = ah; |
40b65f94 | 1191 | |
9db74169 | 1192 | stats->imp_updates_received++; |
cfd46ee4 MM |
1193 | if (!rte_validate(new)) |
1194 | { | |
1195 | rte_trace_in(D_FILTERS, p, new, "invalid"); | |
9db74169 | 1196 | stats->imp_updates_invalid++; |
cfd46ee4 MM |
1197 | goto drop; |
1198 | } | |
cf98be7b | 1199 | |
40b65f94 | 1200 | if (filter == FILTER_REJECT) |
cfd46ee4 | 1201 | { |
9db74169 | 1202 | stats->imp_updates_filtered++; |
cfd46ee4 | 1203 | rte_trace_in(D_FILTERS, p, new, "filtered out"); |
094d2bdb | 1204 | |
15550957 | 1205 | if (! ah->in_keep_filtered) |
cf98be7b OZ |
1206 | goto drop; |
1207 | ||
1208 | /* new is a private copy, i could modify it */ | |
15550957 | 1209 | new->flags |= REF_FILTERED; |
cfd46ee4 | 1210 | } |
cf98be7b | 1211 | else |
e2dc2f30 | 1212 | { |
736e143f | 1213 | tmpa = make_tmp_attrs(new, rte_update_pool); |
cf98be7b | 1214 | if (filter && (filter != FILTER_REJECT)) |
cfd46ee4 | 1215 | { |
cf98be7b OZ |
1216 | ea_list *old_tmpa = tmpa; |
1217 | int fr = f_run(filter, &new, &tmpa, rte_update_pool, 0); | |
1218 | if (fr > F_ACCEPT) | |
1219 | { | |
1220 | stats->imp_updates_filtered++; | |
1221 | rte_trace_in(D_FILTERS, p, new, "filtered out"); | |
1222 | ||
15550957 | 1223 | if (! ah->in_keep_filtered) |
cf98be7b OZ |
1224 | goto drop; |
1225 | ||
15550957 | 1226 | new->flags |= REF_FILTERED; |
cf98be7b | 1227 | } |
736e143f OZ |
1228 | if (tmpa != old_tmpa && src->proto->store_tmp_attrs) |
1229 | src->proto->store_tmp_attrs(new, tmpa); | |
cfd46ee4 | 1230 | } |
e2dc2f30 | 1231 | } |
094d2bdb | 1232 | if (!rta_is_cached(new->attrs)) /* Need to copy attributes */ |
e2dc2f30 MM |
1233 | new->attrs = rta_lookup(new->attrs); |
1234 | new->flags |= REF_COW; | |
1235 | } | |
925fe2d3 | 1236 | else |
094d2bdb OZ |
1237 | { |
1238 | stats->imp_withdraws_received++; | |
1239 | ||
1240 | if (!net || !src) | |
1241 | { | |
1242 | stats->imp_withdraws_ignored++; | |
1243 | rte_update_unlock(); | |
1244 | return; | |
1245 | } | |
1246 | } | |
925fe2d3 | 1247 | |
fad04c75 OZ |
1248 | recalc: |
1249 | rte_hide_dummy_routes(net, &dummy); | |
db027a41 | 1250 | rte_recalculate(ah, net, new, src); |
fad04c75 | 1251 | rte_unhide_dummy_routes(net, &dummy); |
e2dc2f30 MM |
1252 | rte_update_unlock(); |
1253 | return; | |
1254 | ||
fad04c75 | 1255 | drop: |
e2dc2f30 | 1256 | rte_free(new); |
fad04c75 | 1257 | new = NULL; |
fad04c75 | 1258 | goto recalc; |
e2dc2f30 MM |
1259 | } |
1260 | ||
cfe34a31 OZ |
1261 | /* Independent call to rte_announce(), used from next hop |
1262 | recalculation, outside of rte_update(). new must be non-NULL */ | |
1263 | static inline void | |
8d9eef17 OZ |
1264 | rte_announce_i(rtable *tab, unsigned type, net *net, rte *new, rte *old, |
1265 | rte *new_best, rte *old_best) | |
cfe34a31 | 1266 | { |
cfe34a31 | 1267 | rte_update_lock(); |
8d9eef17 | 1268 | rte_announce(tab, type, net, new, old, new_best, old_best, NULL); |
cfe34a31 OZ |
1269 | rte_update_unlock(); |
1270 | } | |
1271 | ||
5b22683d | 1272 | void |
0e02abfd | 1273 | rte_discard(rtable *t, rte *old) /* Non-filtered route deletion, used during garbage collection */ |
5b22683d | 1274 | { |
e2dc2f30 | 1275 | rte_update_lock(); |
db027a41 | 1276 | rte_recalculate(old->sender, old->net, NULL, old->attrs->src); |
e2dc2f30 | 1277 | rte_update_unlock(); |
2326b001 MM |
1278 | } |
1279 | ||
36da2857 OZ |
1280 | /* Check rtable for best route to given net whether it would be exported do p */ |
1281 | int | |
1282 | rt_examine(rtable *t, ip_addr prefix, int pxlen, struct proto *p, struct filter *filter) | |
1283 | { | |
1284 | net *n = net_find(t, prefix, pxlen); | |
1285 | rte *rt = n ? n->routes : NULL; | |
1286 | ||
1287 | if (!rte_is_valid(rt)) | |
1288 | return 0; | |
1289 | ||
1290 | rte_update_lock(); | |
1291 | ||
1292 | /* Rest is stripped down export_filter() */ | |
736e143f | 1293 | ea_list *tmpa = make_tmp_attrs(rt, rte_update_pool); |
36da2857 OZ |
1294 | int v = p->import_control ? p->import_control(p, &rt, &tmpa, rte_update_pool) : 0; |
1295 | if (v == RIC_PROCESS) | |
1296 | v = (f_run(filter, &rt, &tmpa, rte_update_pool, FF_FORCE_TMPATTR) <= F_ACCEPT); | |
1297 | ||
1298 | /* Discard temporary rte */ | |
1299 | if (rt != n->routes) | |
1300 | rte_free(rt); | |
1301 | ||
1302 | rte_update_unlock(); | |
1303 | ||
1304 | return v > 0; | |
1305 | } | |
1306 | ||
6eda3f13 OZ |
1307 | |
1308 | /** | |
1309 | * rt_refresh_begin - start a refresh cycle | |
1310 | * @t: related routing table | |
1311 | * @ah: related announce hook | |
1312 | * | |
1313 | * This function starts a refresh cycle for given routing table and announce | |
1314 | * hook. The refresh cycle is a sequence where the protocol sends all its valid | |
1315 | * routes to the routing table (by rte_update()). After that, all protocol | |
1316 | * routes (more precisely routes with @ah as @sender) not sent during the | |
1317 | * refresh cycle but still in the table from the past are pruned. This is | |
1318 | * implemented by marking all related routes as stale by REF_STALE flag in | |
1319 | * rt_refresh_begin(), then marking all related stale routes with REF_DISCARD | |
1320 | * flag in rt_refresh_end() and then removing such routes in the prune loop. | |
1321 | */ | |
0c791f87 OZ |
1322 | void |
1323 | rt_refresh_begin(rtable *t, struct announce_hook *ah) | |
1324 | { | |
1325 | net *n; | |
1326 | rte *e; | |
1327 | ||
1328 | FIB_WALK(&t->fib, fn) | |
1329 | { | |
1330 | n = (net *) fn; | |
1331 | for (e = n->routes; e; e = e->next) | |
1332 | if (e->sender == ah) | |
1333 | e->flags |= REF_STALE; | |
1334 | } | |
1335 | FIB_WALK_END; | |
1336 | } | |
1337 | ||
6eda3f13 OZ |
1338 | /** |
1339 | * rt_refresh_end - end a refresh cycle | |
1340 | * @t: related routing table | |
1341 | * @ah: related announce hook | |
1342 | * | |
1343 | * This function starts a refresh cycle for given routing table and announce | |
1344 | * hook. See rt_refresh_begin() for description of refresh cycles. | |
1345 | */ | |
0c791f87 OZ |
1346 | void |
1347 | rt_refresh_end(rtable *t, struct announce_hook *ah) | |
1348 | { | |
1349 | int prune = 0; | |
1350 | net *n; | |
1351 | rte *e; | |
1352 | ||
1353 | FIB_WALK(&t->fib, fn) | |
1354 | { | |
1355 | n = (net *) fn; | |
1356 | for (e = n->routes; e; e = e->next) | |
1357 | if ((e->sender == ah) && (e->flags & REF_STALE)) | |
1358 | { | |
1359 | e->flags |= REF_DISCARD; | |
1360 | prune = 1; | |
1361 | } | |
1362 | } | |
1363 | FIB_WALK_END; | |
1364 | ||
1365 | if (prune) | |
1366 | rt_schedule_prune(t); | |
1367 | } | |
1368 | ||
1369 | ||
58740ed4 MM |
1370 | /** |
1371 | * rte_dump - dump a route | |
1372 | * @e: &rte to be dumped | |
1373 | * | |
1374 | * This functions dumps contents of a &rte to debug output. | |
1375 | */ | |
2326b001 | 1376 | void |
a0762910 | 1377 | rte_dump(rte *e) |
2326b001 | 1378 | { |
a0762910 | 1379 | net *n = e->net; |
47c447c4 | 1380 | debug("%-1I/%2d ", n->n.prefix, n->n.pxlen); |
c10421d3 | 1381 | debug("KF=%02x PF=%02x pref=%d lm=%d ", n->n.flags, e->pflags, e->pref, now-e->lastmod); |
0cdbd397 | 1382 | rta_dump(e->attrs); |
094d2bdb OZ |
1383 | if (e->attrs->src->proto->proto->dump_attrs) |
1384 | e->attrs->src->proto->proto->dump_attrs(e); | |
0cdbd397 | 1385 | debug("\n"); |
2326b001 | 1386 | } |
62aa008a | 1387 | |
58740ed4 MM |
1388 | /** |
1389 | * rt_dump - dump a routing table | |
1390 | * @t: routing table to be dumped | |
1391 | * | |
1392 | * This function dumps contents of a given routing table to debug output. | |
1393 | */ | |
2326b001 MM |
1394 | void |
1395 | rt_dump(rtable *t) | |
1396 | { | |
0cdbd397 MM |
1397 | rte *e; |
1398 | net *n; | |
0e02abfd | 1399 | struct announce_hook *a; |
0cdbd397 MM |
1400 | |
1401 | debug("Dump of routing table <%s>\n", t->name); | |
e440395d | 1402 | #ifdef DEBUGGING |
08e2d625 | 1403 | fib_check(&t->fib); |
e440395d | 1404 | #endif |
08e2d625 MM |
1405 | FIB_WALK(&t->fib, fn) |
1406 | { | |
1407 | n = (net *) fn; | |
1408 | for(e=n->routes; e; e=e->next) | |
1409 | rte_dump(e); | |
0cdbd397 | 1410 | } |
08e2d625 | 1411 | FIB_WALK_END; |
0e02abfd MM |
1412 | WALK_LIST(a, t->hooks) |
1413 | debug("\tAnnounces routes to protocol %s\n", a->proto->name); | |
0cdbd397 | 1414 | debug("\n"); |
2326b001 | 1415 | } |
62aa008a | 1416 | |
58740ed4 MM |
1417 | /** |
1418 | * rt_dump_all - dump all routing tables | |
1419 | * | |
1420 | * This function dumps contents of all routing tables to debug output. | |
1421 | */ | |
6d45cf21 MM |
1422 | void |
1423 | rt_dump_all(void) | |
1424 | { | |
0e02abfd MM |
1425 | rtable *t; |
1426 | ||
1427 | WALK_LIST(t, routing_tables) | |
1428 | rt_dump(t); | |
6d45cf21 MM |
1429 | } |
1430 | ||
0c791f87 OZ |
1431 | static inline void |
1432 | rt_schedule_prune(rtable *tab) | |
1433 | { | |
1434 | rt_mark_for_prune(tab); | |
1435 | ev_schedule(tab->rt_event); | |
1436 | } | |
1437 | ||
cfe34a31 OZ |
1438 | static inline void |
1439 | rt_schedule_gc(rtable *tab) | |
1440 | { | |
1441 | if (tab->gc_scheduled) | |
1442 | return; | |
1443 | ||
1444 | tab->gc_scheduled = 1; | |
1445 | ev_schedule(tab->rt_event); | |
1446 | } | |
1447 | ||
1448 | static inline void | |
1449 | rt_schedule_hcu(rtable *tab) | |
1450 | { | |
1451 | if (tab->hcu_scheduled) | |
1452 | return; | |
1453 | ||
1454 | tab->hcu_scheduled = 1; | |
1455 | ev_schedule(tab->rt_event); | |
1456 | } | |
1457 | ||
1458 | static inline void | |
1459 | rt_schedule_nhu(rtable *tab) | |
1460 | { | |
1461 | if (tab->nhu_state == 0) | |
1462 | ev_schedule(tab->rt_event); | |
1463 | ||
1464 | /* state change 0->1, 2->3 */ | |
1465 | tab->nhu_state |= 1; | |
1466 | } | |
1467 | ||
0c791f87 | 1468 | |
fb829de6 OZ |
1469 | static void |
1470 | rt_prune_nets(rtable *tab) | |
1471 | { | |
1472 | struct fib_iterator fit; | |
1473 | int ncnt = 0, ndel = 0; | |
1474 | ||
1475 | #ifdef DEBUGGING | |
1476 | fib_check(&tab->fib); | |
1477 | #endif | |
1478 | ||
1479 | FIB_ITERATE_INIT(&fit, &tab->fib); | |
1480 | again: | |
1481 | FIB_ITERATE_START(&tab->fib, &fit, f) | |
1482 | { | |
1483 | net *n = (net *) f; | |
1484 | ncnt++; | |
1485 | if (!n->routes) /* Orphaned FIB entry */ | |
1486 | { | |
1487 | FIB_ITERATE_PUT(&fit, f); | |
1488 | fib_delete(&tab->fib, f); | |
1489 | ndel++; | |
1490 | goto again; | |
1491 | } | |
1492 | } | |
1493 | FIB_ITERATE_END(f); | |
1494 | DBG("Pruned %d of %d networks\n", ndel, ncnt); | |
1495 | ||
1496 | tab->gc_counter = 0; | |
1497 | tab->gc_time = now; | |
1498 | tab->gc_scheduled = 0; | |
1499 | } | |
1500 | ||
8f6accb5 | 1501 | static void |
cfe34a31 | 1502 | rt_event(void *ptr) |
5996da6a | 1503 | { |
cfe34a31 OZ |
1504 | rtable *tab = ptr; |
1505 | ||
1506 | if (tab->hcu_scheduled) | |
1507 | rt_update_hostcache(tab); | |
0e02abfd | 1508 | |
cfe34a31 OZ |
1509 | if (tab->nhu_state) |
1510 | rt_next_hop_update(tab); | |
1511 | ||
0c791f87 OZ |
1512 | if (tab->prune_state) |
1513 | if (!rt_prune_table(tab)) | |
1514 | { | |
1515 | /* Table prune unfinished */ | |
1516 | ev_schedule(tab->rt_event); | |
1517 | return; | |
1518 | } | |
1519 | ||
cfe34a31 | 1520 | if (tab->gc_scheduled) |
094d2bdb OZ |
1521 | { |
1522 | rt_prune_nets(tab); | |
1523 | rt_prune_sources(); // FIXME this should be moved to independent event | |
1524 | } | |
5996da6a MM |
1525 | } |
1526 | ||
b9626ec6 MM |
1527 | void |
1528 | rt_setup(pool *p, rtable *t, char *name, struct rtable_config *cf) | |
1529 | { | |
1530 | bzero(t, sizeof(*t)); | |
1531 | fib_init(&t->fib, p, sizeof(net), 0, rte_init); | |
1532 | t->name = name; | |
1533 | t->config = cf; | |
1534 | init_list(&t->hooks); | |
1535 | if (cf) | |
1536 | { | |
cfe34a31 OZ |
1537 | t->rt_event = ev_new(p); |
1538 | t->rt_event->hook = rt_event; | |
1539 | t->rt_event->data = t; | |
2eca3b3a | 1540 | t->gc_time = now; |
b9626ec6 MM |
1541 | } |
1542 | } | |
1543 | ||
58740ed4 MM |
1544 | /** |
1545 | * rt_init - initialize routing tables | |
1546 | * | |
1547 | * This function is called during BIRD startup. It initializes the | |
1548 | * routing table module. | |
1549 | */ | |
2326b001 MM |
1550 | void |
1551 | rt_init(void) | |
1552 | { | |
1553 | rta_init(); | |
5996da6a | 1554 | rt_table_pool = rp_new(&root_pool, "Routing tables"); |
e2dc2f30 | 1555 | rte_update_pool = lp_new(rt_table_pool, 4080); |
5996da6a | 1556 | rte_slab = sl_new(rt_table_pool, sizeof(rte)); |
0e02abfd | 1557 | init_list(&routing_tables); |
2326b001 | 1558 | } |
1a54b1c6 | 1559 | |
fb829de6 | 1560 | |
0c791f87 | 1561 | static int |
d0e23d42 | 1562 | rt_prune_step(rtable *tab, int *limit) |
fb829de6 OZ |
1563 | { |
1564 | struct fib_iterator *fit = &tab->prune_fit; | |
1a54b1c6 MM |
1565 | |
1566 | DBG("Pruning route table %s\n", tab->name); | |
0521e4f6 MM |
1567 | #ifdef DEBUGGING |
1568 | fib_check(&tab->fib); | |
1569 | #endif | |
fb829de6 | 1570 | |
0c791f87 | 1571 | if (tab->prune_state == RPS_NONE) |
fb829de6 OZ |
1572 | return 1; |
1573 | ||
0c791f87 | 1574 | if (tab->prune_state == RPS_SCHEDULED) |
fb829de6 OZ |
1575 | { |
1576 | FIB_ITERATE_INIT(fit, &tab->fib); | |
0c791f87 | 1577 | tab->prune_state = RPS_RUNNING; |
fb829de6 OZ |
1578 | } |
1579 | ||
08e2d625 | 1580 | again: |
fb829de6 | 1581 | FIB_ITERATE_START(&tab->fib, fit, fn) |
1a54b1c6 | 1582 | { |
fb829de6 | 1583 | net *n = (net *) fn; |
08e2d625 | 1584 | rte *e; |
fb829de6 | 1585 | |
08e2d625 | 1586 | rescan: |
fb829de6 | 1587 | for (e=n->routes; e; e=e->next) |
d0e23d42 | 1588 | if (e->sender->proto->flushing || (e->flags & REF_DISCARD)) |
08e2d625 | 1589 | { |
0c791f87 | 1590 | if (*limit <= 0) |
fb829de6 OZ |
1591 | { |
1592 | FIB_ITERATE_PUT(fit, fn); | |
1593 | return 0; | |
1594 | } | |
1595 | ||
0e02abfd | 1596 | rte_discard(tab, e); |
0c791f87 | 1597 | (*limit)--; |
fb829de6 | 1598 | |
08e2d625 MM |
1599 | goto rescan; |
1600 | } | |
fb829de6 | 1601 | if (!n->routes) /* Orphaned FIB entry */ |
1a54b1c6 | 1602 | { |
fb829de6 OZ |
1603 | FIB_ITERATE_PUT(fit, fn); |
1604 | fib_delete(&tab->fib, fn); | |
08e2d625 | 1605 | goto again; |
1a54b1c6 | 1606 | } |
1a54b1c6 | 1607 | } |
fb829de6 OZ |
1608 | FIB_ITERATE_END(fn); |
1609 | ||
0521e4f6 MM |
1610 | #ifdef DEBUGGING |
1611 | fib_check(&tab->fib); | |
1612 | #endif | |
fb829de6 | 1613 | |
0c791f87 | 1614 | tab->prune_state = RPS_NONE; |
fb829de6 | 1615 | return 1; |
1a54b1c6 | 1616 | } |
0e02abfd | 1617 | |
6eda3f13 OZ |
1618 | /** |
1619 | * rt_prune_table - prune a routing table | |
8e433d6a | 1620 | * @tab: a routing table for pruning |
6eda3f13 OZ |
1621 | * |
1622 | * This function scans the routing table @tab and removes routes belonging to | |
1623 | * flushing protocols, discarded routes and also stale network entries, in a | |
1624 | * similar fashion like rt_prune_loop(). Returns 1 when all such routes are | |
1625 | * pruned. Contrary to rt_prune_loop(), this function is not a part of the | |
1626 | * protocol flushing loop, but it is called from rt_event() for just one routing | |
1627 | * table. | |
1628 | * | |
1629 | * Note that rt_prune_table() and rt_prune_loop() share (for each table) the | |
1630 | * prune state (@prune_state) and also the pruning iterator (@prune_fit). | |
1631 | */ | |
0c791f87 OZ |
1632 | static inline int |
1633 | rt_prune_table(rtable *tab) | |
1634 | { | |
1635 | int limit = 512; | |
d0e23d42 | 1636 | return rt_prune_step(tab, &limit); |
0c791f87 OZ |
1637 | } |
1638 | ||
58740ed4 | 1639 | /** |
fb829de6 | 1640 | * rt_prune_loop - prune routing tables |
58740ed4 | 1641 | * |
6eda3f13 OZ |
1642 | * The prune loop scans routing tables and removes routes belonging to flushing |
1643 | * protocols, discarded routes and also stale network entries. Returns 1 when | |
1644 | * all such routes are pruned. It is a part of the protocol flushing loop. | |
58740ed4 | 1645 | */ |
fb829de6 OZ |
1646 | int |
1647 | rt_prune_loop(void) | |
0e02abfd | 1648 | { |
0c791f87 | 1649 | int limit = 512; |
9135c1f0 | 1650 | rtable *t; |
0e02abfd MM |
1651 | |
1652 | WALK_LIST(t, routing_tables) | |
d0e23d42 | 1653 | if (! rt_prune_step(t, &limit)) |
fb829de6 OZ |
1654 | return 0; |
1655 | ||
1656 | return 1; | |
0e02abfd MM |
1657 | } |
1658 | ||
cfe34a31 OZ |
1659 | void |
1660 | rt_preconfig(struct config *c) | |
1661 | { | |
9b9a7143 | 1662 | struct symbol *s = cf_get_symbol("master"); |
cfe34a31 OZ |
1663 | |
1664 | init_list(&c->tables); | |
1665 | c->master_rtc = rt_new_table(s); | |
1666 | } | |
1667 | ||
1668 | ||
1669 | /* | |
1670 | * Some functions for handing internal next hop updates | |
1671 | * triggered by rt_schedule_nhu(). | |
1672 | */ | |
1673 | ||
cfe34a31 OZ |
1674 | static inline int |
1675 | rta_next_hop_outdated(rta *a) | |
1676 | { | |
1677 | struct hostentry *he = a->hostentry; | |
7e95c05d OZ |
1678 | |
1679 | if (!he) | |
1680 | return 0; | |
1681 | ||
1682 | if (!he->src) | |
1683 | return a->dest != RTD_UNREACHABLE; | |
1684 | ||
1685 | return (a->iface != he->src->iface) || !ipa_equal(a->gw, he->gw) || | |
1686 | (a->dest != he->dest) || (a->igp_metric != he->igp_metric) || | |
1687 | !mpnh_same(a->nexthops, he->src->nexthops); | |
cfe34a31 OZ |
1688 | } |
1689 | ||
1690 | static inline void | |
1691 | rta_apply_hostentry(rta *a, struct hostentry *he) | |
1692 | { | |
1693 | a->hostentry = he; | |
7e95c05d | 1694 | a->iface = he->src ? he->src->iface : NULL; |
cfe34a31 OZ |
1695 | a->gw = he->gw; |
1696 | a->dest = he->dest; | |
d1e146f2 | 1697 | a->igp_metric = he->igp_metric; |
7e95c05d | 1698 | a->nexthops = he->src ? he->src->nexthops : NULL; |
cfe34a31 OZ |
1699 | } |
1700 | ||
1701 | static inline rte * | |
1702 | rt_next_hop_update_rte(rtable *tab, rte *old) | |
1703 | { | |
1704 | rta a; | |
1705 | memcpy(&a, old->attrs, sizeof(rta)); | |
1706 | rta_apply_hostentry(&a, old->attrs->hostentry); | |
1707 | a.aflags = 0; | |
1708 | ||
1709 | rte *e = sl_alloc(rte_slab); | |
1710 | memcpy(e, old, sizeof(rte)); | |
1711 | e->attrs = rta_lookup(&a); | |
1712 | ||
1713 | return e; | |
1714 | } | |
1715 | ||
1716 | static inline int | |
1717 | rt_next_hop_update_net(rtable *tab, net *n) | |
1718 | { | |
1719 | rte **k, *e, *new, *old_best, **new_best; | |
1720 | int count = 0; | |
1721 | int free_old_best = 0; | |
1722 | ||
1723 | old_best = n->routes; | |
1724 | if (!old_best) | |
1725 | return 0; | |
1726 | ||
cfe34a31 | 1727 | for (k = &n->routes; e = *k; k = &e->next) |
be4cd99a OZ |
1728 | if (rta_next_hop_outdated(e->attrs)) |
1729 | { | |
1730 | new = rt_next_hop_update_rte(tab, e); | |
1731 | *k = new; | |
cfe34a31 | 1732 | |
8d9eef17 | 1733 | rte_announce_i(tab, RA_ANY, n, new, e, NULL, NULL); |
c0adf7e9 | 1734 | rte_trace_in(D_ROUTES, new->sender->proto, new, "updated"); |
cfe34a31 | 1735 | |
be4cd99a OZ |
1736 | /* Call a pre-comparison hook */ |
1737 | /* Not really an efficient way to compute this */ | |
094d2bdb OZ |
1738 | if (e->attrs->src->proto->rte_recalculate) |
1739 | e->attrs->src->proto->rte_recalculate(tab, n, new, e, NULL); | |
cfe34a31 | 1740 | |
be4cd99a OZ |
1741 | if (e != old_best) |
1742 | rte_free_quick(e); | |
1743 | else /* Freeing of the old best rte is postponed */ | |
1744 | free_old_best = 1; | |
cfe34a31 | 1745 | |
be4cd99a OZ |
1746 | e = new; |
1747 | count++; | |
1748 | } | |
1749 | ||
1750 | if (!count) | |
1751 | return 0; | |
1752 | ||
1753 | /* Find the new best route */ | |
1754 | new_best = NULL; | |
1755 | for (k = &n->routes; e = *k; k = &e->next) | |
1756 | { | |
cfe34a31 OZ |
1757 | if (!new_best || rte_better(e, *new_best)) |
1758 | new_best = k; | |
1759 | } | |
1760 | ||
1761 | /* Relink the new best route to the first position */ | |
1762 | new = *new_best; | |
1763 | if (new != n->routes) | |
1764 | { | |
1765 | *new_best = new->next; | |
1766 | new->next = n->routes; | |
1767 | n->routes = new; | |
1768 | } | |
1769 | ||
1770 | /* Announce the new best route */ | |
1771 | if (new != old_best) | |
1772 | { | |
8d9eef17 | 1773 | rte_announce_i(tab, RA_OPTIMAL, n, new, old_best, NULL, NULL); |
c0adf7e9 | 1774 | rte_trace_in(D_ROUTES, new->sender->proto, new, "updated [best]"); |
cfe34a31 OZ |
1775 | } |
1776 | ||
8d9eef17 OZ |
1777 | /* FIXME: Better announcement of merged routes */ |
1778 | rte_announce_i(tab, RA_MERGED, n, new, old_best, new, old_best); | |
1779 | ||
d107ef78 | 1780 | if (free_old_best) |
cfe34a31 OZ |
1781 | rte_free_quick(old_best); |
1782 | ||
1783 | return count; | |
1784 | } | |
1785 | ||
1786 | static void | |
1787 | rt_next_hop_update(rtable *tab) | |
1788 | { | |
1789 | struct fib_iterator *fit = &tab->nhu_fit; | |
1790 | int max_feed = 32; | |
1791 | ||
1792 | if (tab->nhu_state == 0) | |
1793 | return; | |
1794 | ||
1795 | if (tab->nhu_state == 1) | |
1796 | { | |
1797 | FIB_ITERATE_INIT(fit, &tab->fib); | |
1798 | tab->nhu_state = 2; | |
1799 | } | |
1800 | ||
1801 | FIB_ITERATE_START(&tab->fib, fit, fn) | |
1802 | { | |
1803 | if (max_feed <= 0) | |
1804 | { | |
1805 | FIB_ITERATE_PUT(fit, fn); | |
1806 | ev_schedule(tab->rt_event); | |
1807 | return; | |
1808 | } | |
1809 | max_feed -= rt_next_hop_update_net(tab, (net *) fn); | |
1810 | } | |
1811 | FIB_ITERATE_END(fn); | |
1812 | ||
1813 | /* state change 2->0, 3->1 */ | |
1814 | tab->nhu_state &= 1; | |
1815 | ||
1816 | if (tab->nhu_state > 0) | |
1817 | ev_schedule(tab->rt_event); | |
1818 | } | |
1819 | ||
1820 | ||
b9626ec6 MM |
1821 | struct rtable_config * |
1822 | rt_new_table(struct symbol *s) | |
1823 | { | |
36415e4b OZ |
1824 | /* Hack that allows to 'redefine' the master table */ |
1825 | if ((s->class == SYM_TABLE) && (s->def == new_config->master_rtc)) | |
1826 | return s->def; | |
1827 | ||
b9626ec6 MM |
1828 | struct rtable_config *c = cfg_allocz(sizeof(struct rtable_config)); |
1829 | ||
1830 | cf_define_symbol(s, SYM_TABLE, c); | |
1831 | c->name = s->name; | |
1832 | add_tail(&new_config->tables, &c->n); | |
2eca3b3a | 1833 | c->gc_max_ops = 1000; |
b9626ec6 MM |
1834 | c->gc_min_time = 5; |
1835 | return c; | |
1836 | } | |
1837 | ||
58740ed4 MM |
1838 | /** |
1839 | * rt_lock_table - lock a routing table | |
1840 | * @r: routing table to be locked | |
1841 | * | |
1842 | * Lock a routing table, because it's in use by a protocol, | |
1843 | * preventing it from being freed when it gets undefined in a new | |
1844 | * configuration. | |
1845 | */ | |
0e02abfd | 1846 | void |
50fe90ed | 1847 | rt_lock_table(rtable *r) |
0e02abfd | 1848 | { |
50fe90ed MM |
1849 | r->use_count++; |
1850 | } | |
1851 | ||
58740ed4 MM |
1852 | /** |
1853 | * rt_unlock_table - unlock a routing table | |
1854 | * @r: routing table to be unlocked | |
1855 | * | |
1856 | * Unlock a routing table formerly locked by rt_lock_table(), | |
1857 | * that is decrease its use count and delete it if it's scheduled | |
1858 | * for deletion by configuration changes. | |
1859 | */ | |
50fe90ed MM |
1860 | void |
1861 | rt_unlock_table(rtable *r) | |
1862 | { | |
1863 | if (!--r->use_count && r->deleted) | |
1864 | { | |
1865 | struct config *conf = r->deleted; | |
1866 | DBG("Deleting routing table %s\n", r->name); | |
86b4e170 | 1867 | r->config->table = NULL; |
cfe34a31 OZ |
1868 | if (r->hostcache) |
1869 | rt_free_hostcache(r); | |
50fe90ed MM |
1870 | rem_node(&r->n); |
1871 | fib_free(&r->fib); | |
cfe34a31 | 1872 | rfree(r->rt_event); |
50fe90ed MM |
1873 | mb_free(r); |
1874 | config_del_obstacle(conf); | |
1875 | } | |
1876 | } | |
1877 | ||
58740ed4 MM |
1878 | /** |
1879 | * rt_commit - commit new routing table configuration | |
1880 | * @new: new configuration | |
1881 | * @old: original configuration or %NULL if it's boot time config | |
1882 | * | |
1883 | * Scan differences between @old and @new configuration and modify | |
1884 | * the routing tables according to these changes. If @new defines a | |
1885 | * previously unknown table, create it, if it omits a table existing | |
1886 | * in @old, schedule it for deletion (it gets deleted when all protocols | |
1887 | * disconnect from it by calling rt_unlock_table()), if it exists | |
1888 | * in both configurations, leave it unchanged. | |
1889 | */ | |
50fe90ed MM |
1890 | void |
1891 | rt_commit(struct config *new, struct config *old) | |
1892 | { | |
1893 | struct rtable_config *o, *r; | |
0e02abfd | 1894 | |
50fe90ed MM |
1895 | DBG("rt_commit:\n"); |
1896 | if (old) | |
0e02abfd | 1897 | { |
50fe90ed MM |
1898 | WALK_LIST(o, old->tables) |
1899 | { | |
1900 | rtable *ot = o->table; | |
1901 | if (!ot->deleted) | |
1902 | { | |
9b9a7143 | 1903 | struct symbol *sym = cf_find_symbol(new, o->name); |
bf8558bc | 1904 | if (sym && sym->class == SYM_TABLE && !new->shutdown) |
50fe90ed MM |
1905 | { |
1906 | DBG("\t%s: same\n", o->name); | |
1907 | r = sym->def; | |
1908 | r->table = ot; | |
1909 | ot->name = r->name; | |
b9626ec6 | 1910 | ot->config = r; |
26822d8f OZ |
1911 | if (o->sorted != r->sorted) |
1912 | log(L_WARN "Reconfiguration of rtable sorted flag not implemented"); | |
50fe90ed MM |
1913 | } |
1914 | else | |
1915 | { | |
bf8558bc | 1916 | DBG("\t%s: deleted\n", o->name); |
50fe90ed MM |
1917 | ot->deleted = old; |
1918 | config_add_obstacle(old); | |
1919 | rt_lock_table(ot); | |
1920 | rt_unlock_table(ot); | |
1921 | } | |
1922 | } | |
1923 | } | |
0e02abfd | 1924 | } |
50fe90ed MM |
1925 | |
1926 | WALK_LIST(r, new->tables) | |
1927 | if (!r->table) | |
1928 | { | |
1929 | rtable *t = mb_alloc(rt_table_pool, sizeof(struct rtable)); | |
1930 | DBG("\t%s: created\n", r->name); | |
b9626ec6 | 1931 | rt_setup(rt_table_pool, t, r->name, r); |
50fe90ed MM |
1932 | add_tail(&routing_tables, &t->n); |
1933 | r->table = t; | |
1934 | } | |
1935 | DBG("\tdone\n"); | |
0e02abfd | 1936 | } |
730f2e2c | 1937 | |
23ac9e9a OZ |
1938 | static inline void |
1939 | do_feed_baby(struct proto *p, int type, struct announce_hook *h, net *n, rte *e) | |
1940 | { | |
23ac9e9a | 1941 | rte_update_lock(); |
00a09f3c | 1942 | if (type == RA_ACCEPTED) |
db027a41 | 1943 | rt_notify_accepted(h, n, e, NULL, NULL, p->refeeding ? 2 : 1); |
8d9eef17 OZ |
1944 | else if (type == RA_MERGED) |
1945 | rt_notify_merged(h, n, NULL, NULL, e, p->refeeding ? e : NULL, p->refeeding); | |
00a09f3c | 1946 | else |
db027a41 | 1947 | rt_notify_basic(h, n, e, p->refeeding ? e : NULL, p->refeeding); |
23ac9e9a OZ |
1948 | rte_update_unlock(); |
1949 | } | |
1950 | ||
58740ed4 MM |
1951 | /** |
1952 | * rt_feed_baby - advertise routes to a new protocol | |
1953 | * @p: protocol to be fed | |
1954 | * | |
1955 | * This function performs one pass of advertisement of routes to a newly | |
1956 | * initialized protocol. It's called by the protocol code as long as it | |
1957 | * has something to do. (We avoid transferring all the routes in single | |
1958 | * pass in order not to monopolize CPU time.) | |
1959 | */ | |
ac5d8012 MM |
1960 | int |
1961 | rt_feed_baby(struct proto *p) | |
1962 | { | |
1963 | struct announce_hook *h; | |
1964 | struct fib_iterator *fit; | |
76dfda9e | 1965 | int max_feed = 256; |
ac5d8012 MM |
1966 | |
1967 | if (!p->feed_ahook) /* Need to initialize first */ | |
1968 | { | |
1969 | if (!p->ahooks) | |
1970 | return 1; | |
1971 | DBG("Announcing routes to new protocol %s\n", p->name); | |
1972 | p->feed_ahook = p->ahooks; | |
1973 | fit = p->feed_iterator = mb_alloc(p->pool, sizeof(struct fib_iterator)); | |
1974 | goto next_hook; | |
1975 | } | |
1976 | fit = p->feed_iterator; | |
1977 | ||
1978 | again: | |
1979 | h = p->feed_ahook; | |
1980 | FIB_ITERATE_START(&h->table->fib, fit, fn) | |
1981 | { | |
1982 | net *n = (net *) fn; | |
258d0ad4 | 1983 | rte *e = n->routes; |
76dfda9e MM |
1984 | if (max_feed <= 0) |
1985 | { | |
1986 | FIB_ITERATE_PUT(fit, fn); | |
1987 | return 0; | |
1988 | } | |
23ac9e9a | 1989 | |
cf98be7b OZ |
1990 | /* XXXX perhaps we should change feed for RA_ACCEPTED to not use 'new' */ |
1991 | ||
b7f3df79 | 1992 | if ((p->accept_ra_types == RA_OPTIMAL) || |
8d9eef17 OZ |
1993 | (p->accept_ra_types == RA_ACCEPTED) || |
1994 | (p->accept_ra_types == RA_MERGED)) | |
cf98be7b | 1995 | if (rte_is_valid(e)) |
23ac9e9a | 1996 | { |
0c791f87 | 1997 | if (p->export_state != ES_FEEDING) |
23ac9e9a | 1998 | return 1; /* In the meantime, the protocol fell down. */ |
ca34698c | 1999 | |
b7f3df79 | 2000 | do_feed_baby(p, p->accept_ra_types, h, n, e); |
23ac9e9a OZ |
2001 | max_feed--; |
2002 | } | |
2003 | ||
2004 | if (p->accept_ra_types == RA_ANY) | |
ca34698c | 2005 | for(e = n->routes; e; e = e->next) |
23ac9e9a | 2006 | { |
0c791f87 | 2007 | if (p->export_state != ES_FEEDING) |
23ac9e9a | 2008 | return 1; /* In the meantime, the protocol fell down. */ |
ca34698c OZ |
2009 | |
2010 | if (!rte_is_valid(e)) | |
2011 | continue; | |
2012 | ||
23ac9e9a OZ |
2013 | do_feed_baby(p, RA_ANY, h, n, e); |
2014 | max_feed--; | |
2015 | } | |
ac5d8012 MM |
2016 | } |
2017 | FIB_ITERATE_END(fn); | |
2018 | p->feed_ahook = h->next; | |
2019 | if (!p->feed_ahook) | |
2020 | { | |
2021 | mb_free(p->feed_iterator); | |
2022 | p->feed_iterator = NULL; | |
2023 | return 1; | |
2024 | } | |
2025 | ||
2026 | next_hook: | |
2027 | h = p->feed_ahook; | |
2028 | FIB_ITERATE_INIT(fit, &h->table->fib); | |
2029 | goto again; | |
2030 | } | |
2031 | ||
58740ed4 MM |
2032 | /** |
2033 | * rt_feed_baby_abort - abort protocol feeding | |
2034 | * @p: protocol | |
2035 | * | |
2036 | * This function is called by the protocol code when the protocol | |
2037 | * stops or ceases to exist before the last iteration of rt_feed_baby() | |
2038 | * has finished. | |
2039 | */ | |
ac5d8012 MM |
2040 | void |
2041 | rt_feed_baby_abort(struct proto *p) | |
2042 | { | |
2043 | if (p->feed_ahook) | |
2044 | { | |
2045 | /* Unlink the iterator and exit */ | |
2046 | fit_get(&p->feed_ahook->table->fib, p->feed_iterator); | |
2047 | p->feed_ahook = NULL; | |
2048 | } | |
2049 | } | |
2050 | ||
f2b76f2c OZ |
2051 | |
2052 | static inline unsigned | |
2053 | ptr_hash(void *ptr) | |
2054 | { | |
2055 | uintptr_t p = (uintptr_t) ptr; | |
2056 | return p ^ (p << 8) ^ (p >> 16); | |
2057 | } | |
2058 | ||
2059 | static inline unsigned | |
2060 | hc_hash(ip_addr a, rtable *dep) | |
2061 | { | |
2062 | return (ipa_hash(a) ^ ptr_hash(dep)) & 0xffff; | |
2063 | } | |
2064 | ||
2065 | static inline void | |
2066 | hc_insert(struct hostcache *hc, struct hostentry *he) | |
2067 | { | |
ae80a2de | 2068 | uint k = he->hash_key >> hc->hash_shift; |
f2b76f2c OZ |
2069 | he->next = hc->hash_table[k]; |
2070 | hc->hash_table[k] = he; | |
2071 | } | |
2072 | ||
2073 | static inline void | |
2074 | hc_remove(struct hostcache *hc, struct hostentry *he) | |
2075 | { | |
2076 | struct hostentry **hep; | |
ae80a2de | 2077 | uint k = he->hash_key >> hc->hash_shift; |
f2b76f2c OZ |
2078 | |
2079 | for (hep = &hc->hash_table[k]; *hep != he; hep = &(*hep)->next); | |
2080 | *hep = he->next; | |
2081 | } | |
2082 | ||
2083 | #define HC_DEF_ORDER 10 | |
2084 | #define HC_HI_MARK *4 | |
2085 | #define HC_HI_STEP 2 | |
2086 | #define HC_HI_ORDER 16 /* Must be at most 16 */ | |
2087 | #define HC_LO_MARK /5 | |
2088 | #define HC_LO_STEP 2 | |
2089 | #define HC_LO_ORDER 10 | |
2090 | ||
2091 | static void | |
2092 | hc_alloc_table(struct hostcache *hc, unsigned order) | |
2093 | { | |
2094 | unsigned hsize = 1 << order; | |
2095 | hc->hash_order = order; | |
2096 | hc->hash_shift = 16 - order; | |
2097 | hc->hash_max = (order >= HC_HI_ORDER) ? ~0 : (hsize HC_HI_MARK); | |
2098 | hc->hash_min = (order <= HC_LO_ORDER) ? 0 : (hsize HC_LO_MARK); | |
2099 | ||
2100 | hc->hash_table = mb_allocz(rt_table_pool, hsize * sizeof(struct hostentry *)); | |
2101 | } | |
2102 | ||
cfe34a31 | 2103 | static void |
f2b76f2c | 2104 | hc_resize(struct hostcache *hc, unsigned new_order) |
cfe34a31 | 2105 | { |
f2b76f2c OZ |
2106 | unsigned old_size = 1 << hc->hash_order; |
2107 | struct hostentry **old_table = hc->hash_table; | |
2108 | struct hostentry *he, *hen; | |
2109 | int i; | |
2110 | ||
2111 | hc_alloc_table(hc, new_order); | |
2112 | for (i = 0; i < old_size; i++) | |
2113 | for (he = old_table[i]; he != NULL; he=hen) | |
2114 | { | |
2115 | hen = he->next; | |
2116 | hc_insert(hc, he); | |
2117 | } | |
2118 | mb_free(old_table); | |
2119 | } | |
2120 | ||
2121 | static struct hostentry * | |
1b180121 | 2122 | hc_new_hostentry(struct hostcache *hc, ip_addr a, ip_addr ll, rtable *dep, unsigned k) |
f2b76f2c OZ |
2123 | { |
2124 | struct hostentry *he = sl_alloc(hc->slab); | |
2125 | ||
2126 | he->addr = a; | |
1b180121 | 2127 | he->link = ll; |
f2b76f2c OZ |
2128 | he->tab = dep; |
2129 | he->hash_key = k; | |
2130 | he->uc = 0; | |
7e95c05d | 2131 | he->src = NULL; |
f2b76f2c OZ |
2132 | |
2133 | add_tail(&hc->hostentries, &he->ln); | |
2134 | hc_insert(hc, he); | |
2135 | ||
2136 | hc->hash_items++; | |
2137 | if (hc->hash_items > hc->hash_max) | |
2138 | hc_resize(hc, hc->hash_order + HC_HI_STEP); | |
2139 | ||
2140 | return he; | |
2141 | } | |
2142 | ||
2143 | static void | |
2144 | hc_delete_hostentry(struct hostcache *hc, struct hostentry *he) | |
2145 | { | |
7e95c05d OZ |
2146 | rta_free(he->src); |
2147 | ||
f2b76f2c OZ |
2148 | rem_node(&he->ln); |
2149 | hc_remove(hc, he); | |
2150 | sl_free(hc->slab, he); | |
2151 | ||
2152 | hc->hash_items--; | |
2153 | if (hc->hash_items < hc->hash_min) | |
2154 | hc_resize(hc, hc->hash_order - HC_LO_STEP); | |
cfe34a31 OZ |
2155 | } |
2156 | ||
2157 | static void | |
2158 | rt_init_hostcache(rtable *tab) | |
2159 | { | |
2160 | struct hostcache *hc = mb_allocz(rt_table_pool, sizeof(struct hostcache)); | |
2161 | init_list(&hc->hostentries); | |
f2b76f2c OZ |
2162 | |
2163 | hc->hash_items = 0; | |
2164 | hc_alloc_table(hc, HC_DEF_ORDER); | |
2165 | hc->slab = sl_new(rt_table_pool, sizeof(struct hostentry)); | |
2166 | ||
c477f489 | 2167 | hc->lp = lp_new(rt_table_pool, 1008); |
51762a45 | 2168 | hc->trie = f_new_trie(hc->lp, sizeof(struct f_trie_node)); |
c477f489 | 2169 | |
cfe34a31 OZ |
2170 | tab->hostcache = hc; |
2171 | } | |
2172 | ||
2173 | static void | |
2174 | rt_free_hostcache(rtable *tab) | |
2175 | { | |
2176 | struct hostcache *hc = tab->hostcache; | |
2177 | ||
2178 | node *n; | |
2179 | WALK_LIST(n, hc->hostentries) | |
2180 | { | |
2181 | struct hostentry *he = SKIP_BACK(struct hostentry, ln, n); | |
7e95c05d OZ |
2182 | rta_free(he->src); |
2183 | ||
cfe34a31 OZ |
2184 | if (he->uc) |
2185 | log(L_ERR "Hostcache is not empty in table %s", tab->name); | |
2186 | } | |
2187 | ||
f2b76f2c | 2188 | rfree(hc->slab); |
c477f489 | 2189 | rfree(hc->lp); |
f2b76f2c | 2190 | mb_free(hc->hash_table); |
cfe34a31 OZ |
2191 | mb_free(hc); |
2192 | } | |
2193 | ||
2194 | static void | |
2195 | rt_notify_hostcache(rtable *tab, net *net) | |
2196 | { | |
2197 | struct hostcache *hc = tab->hostcache; | |
2198 | ||
2199 | if (tab->hcu_scheduled) | |
2200 | return; | |
2201 | ||
c477f489 OZ |
2202 | if (trie_match_prefix(hc->trie, net->n.prefix, net->n.pxlen)) |
2203 | rt_schedule_hcu(tab); | |
cfe34a31 OZ |
2204 | } |
2205 | ||
2206 | static int | |
2207 | if_local_addr(ip_addr a, struct iface *i) | |
2208 | { | |
2209 | struct ifa *b; | |
2210 | ||
2211 | WALK_LIST(b, i->addrs) | |
2212 | if (ipa_equal(a, b->ip)) | |
2213 | return 1; | |
2214 | ||
2215 | return 0; | |
2216 | } | |
2217 | ||
d1e146f2 OZ |
2218 | static u32 |
2219 | rt_get_igp_metric(rte *rt) | |
2220 | { | |
ba5e5940 OZ |
2221 | eattr *ea = ea_find(rt->attrs->eattrs, EA_GEN_IGP_METRIC); |
2222 | ||
2223 | if (ea) | |
2224 | return ea->u.data; | |
2225 | ||
d1e146f2 | 2226 | rta *a = rt->attrs; |
b7c48981 OF |
2227 | |
2228 | #ifdef CONFIG_OSPF | |
d1e146f2 OZ |
2229 | if ((a->source == RTS_OSPF) || |
2230 | (a->source == RTS_OSPF_IA) || | |
2231 | (a->source == RTS_OSPF_EXT1)) | |
2232 | return rt->u.ospf.metric1; | |
b7c48981 | 2233 | #endif |
d1e146f2 | 2234 | |
b7c48981 | 2235 | #ifdef CONFIG_RIP |
d1e146f2 OZ |
2236 | if (a->source == RTS_RIP) |
2237 | return rt->u.rip.metric; | |
b7c48981 | 2238 | #endif |
d1e146f2 OZ |
2239 | |
2240 | /* Device routes */ | |
7e95c05d | 2241 | if ((a->dest != RTD_ROUTER) && (a->dest != RTD_MULTIPATH)) |
d1e146f2 OZ |
2242 | return 0; |
2243 | ||
2244 | return IGP_METRIC_UNKNOWN; | |
2245 | } | |
2246 | ||
cfe34a31 OZ |
2247 | static int |
2248 | rt_update_hostentry(rtable *tab, struct hostentry *he) | |
2249 | { | |
7e95c05d | 2250 | rta *old_src = he->src; |
c477f489 | 2251 | int pxlen = 0; |
cfe34a31 | 2252 | |
7e95c05d OZ |
2253 | /* Reset the hostentry */ |
2254 | he->src = NULL; | |
2255 | he->gw = IPA_NONE; | |
2256 | he->dest = RTD_UNREACHABLE; | |
2257 | he->igp_metric = 0; | |
2258 | ||
d1e146f2 OZ |
2259 | net *n = net_route(tab, he->addr, MAX_PREFIX_LENGTH); |
2260 | if (n) | |
cfe34a31 | 2261 | { |
cf98be7b OZ |
2262 | rte *e = n->routes; |
2263 | rta *a = e->attrs; | |
c477f489 | 2264 | pxlen = n->n.pxlen; |
cfe34a31 | 2265 | |
2c9033af OZ |
2266 | if (a->hostentry) |
2267 | { | |
2268 | /* Recursive route should not depend on another recursive route */ | |
2269 | log(L_WARN "Next hop address %I resolvable through recursive route for %I/%d", | |
7e95c05d OZ |
2270 | he->addr, n->n.prefix, pxlen); |
2271 | goto done; | |
2c9033af | 2272 | } |
7e95c05d OZ |
2273 | |
2274 | if (a->dest == RTD_DEVICE) | |
cfe34a31 | 2275 | { |
f2b76f2c | 2276 | if (if_local_addr(he->addr, a->iface)) |
cfe34a31 OZ |
2277 | { |
2278 | /* The host address is a local address, this is not valid */ | |
2279 | log(L_WARN "Next hop address %I is a local address of iface %s", | |
f2b76f2c | 2280 | he->addr, a->iface->name); |
7e95c05d | 2281 | goto done; |
cfe34a31 | 2282 | } |
7e95c05d OZ |
2283 | |
2284 | /* The host is directly reachable, use link as a gateway */ | |
2285 | he->gw = he->link; | |
2286 | he->dest = RTD_ROUTER; | |
cfe34a31 OZ |
2287 | } |
2288 | else | |
2289 | { | |
2290 | /* The host is reachable through some route entry */ | |
cfe34a31 OZ |
2291 | he->gw = a->gw; |
2292 | he->dest = a->dest; | |
2293 | } | |
d1e146f2 | 2294 | |
7e95c05d | 2295 | he->src = rta_clone(a); |
cf98be7b | 2296 | he->igp_metric = rt_get_igp_metric(e); |
cfe34a31 OZ |
2297 | } |
2298 | ||
7e95c05d | 2299 | done: |
c477f489 OZ |
2300 | /* Add a prefix range to the trie */ |
2301 | trie_add_prefix(tab->hostcache->trie, he->addr, MAX_PREFIX_LENGTH, pxlen, MAX_PREFIX_LENGTH); | |
2302 | ||
7e95c05d OZ |
2303 | rta_free(old_src); |
2304 | return old_src != he->src; | |
cfe34a31 OZ |
2305 | } |
2306 | ||
2307 | static void | |
2308 | rt_update_hostcache(rtable *tab) | |
2309 | { | |
2310 | struct hostcache *hc = tab->hostcache; | |
2311 | struct hostentry *he; | |
2312 | node *n, *x; | |
2313 | ||
c477f489 OZ |
2314 | /* Reset the trie */ |
2315 | lp_flush(hc->lp); | |
51762a45 | 2316 | hc->trie = f_new_trie(hc->lp, sizeof(struct f_trie_node)); |
c477f489 | 2317 | |
cfe34a31 OZ |
2318 | WALK_LIST_DELSAFE(n, x, hc->hostentries) |
2319 | { | |
2320 | he = SKIP_BACK(struct hostentry, ln, n); | |
2321 | if (!he->uc) | |
2322 | { | |
f2b76f2c | 2323 | hc_delete_hostentry(hc, he); |
cfe34a31 OZ |
2324 | continue; |
2325 | } | |
2326 | ||
2327 | if (rt_update_hostentry(tab, he)) | |
2328 | rt_schedule_nhu(he->tab); | |
2329 | } | |
2330 | ||
2331 | tab->hcu_scheduled = 0; | |
2332 | } | |
2333 | ||
2334 | static struct hostentry * | |
094d2bdb | 2335 | rt_get_hostentry(rtable *tab, ip_addr a, ip_addr ll, rtable *dep) |
cfe34a31 OZ |
2336 | { |
2337 | struct hostentry *he; | |
2338 | ||
2339 | if (!tab->hostcache) | |
2340 | rt_init_hostcache(tab); | |
2341 | ||
ae80a2de | 2342 | uint k = hc_hash(a, dep); |
f2b76f2c OZ |
2343 | struct hostcache *hc = tab->hostcache; |
2344 | for (he = hc->hash_table[k >> hc->hash_shift]; he != NULL; he = he->next) | |
2345 | if (ipa_equal(he->addr, a) && (he->tab == dep)) | |
2346 | return he; | |
cfe34a31 | 2347 | |
1b180121 | 2348 | he = hc_new_hostentry(hc, a, ll, dep, k); |
f2b76f2c | 2349 | rt_update_hostentry(tab, he); |
cfe34a31 OZ |
2350 | return he; |
2351 | } | |
2352 | ||
2353 | void | |
1b180121 | 2354 | rta_set_recursive_next_hop(rtable *dep, rta *a, rtable *tab, ip_addr *gw, ip_addr *ll) |
cfe34a31 | 2355 | { |
094d2bdb | 2356 | rta_apply_hostentry(a, rt_get_hostentry(tab, *gw, *ll, dep)); |
cfe34a31 OZ |
2357 | } |
2358 | ||
094d2bdb | 2359 | |
730f2e2c MM |
2360 | /* |
2361 | * CLI commands | |
2362 | */ | |
2363 | ||
6887f409 OF |
2364 | static byte * |
2365 | rt_format_via(rte *e) | |
730f2e2c | 2366 | { |
730f2e2c MM |
2367 | rta *a = e->attrs; |
2368 | ||
6887f409 OF |
2369 | /* Max text length w/o IP addr and interface name is 16 */ |
2370 | static byte via[STD_ADDRESS_P_LENGTH+sizeof(a->iface->name)+16]; | |
2371 | ||
730f2e2c MM |
2372 | switch (a->dest) |
2373 | { | |
2374 | case RTD_ROUTER: bsprintf(via, "via %I on %s", a->gw, a->iface->name); break; | |
2375 | case RTD_DEVICE: bsprintf(via, "dev %s", a->iface->name); break; | |
2376 | case RTD_BLACKHOLE: bsprintf(via, "blackhole"); break; | |
2377 | case RTD_UNREACHABLE: bsprintf(via, "unreachable"); break; | |
2378 | case RTD_PROHIBIT: bsprintf(via, "prohibited"); break; | |
7e95c05d | 2379 | case RTD_MULTIPATH: bsprintf(via, "multipath"); break; |
730f2e2c MM |
2380 | default: bsprintf(via, "???"); |
2381 | } | |
6887f409 | 2382 | return via; |
cfd46ee4 MM |
2383 | } |
2384 | ||
2385 | static void | |
ce1da96e | 2386 | rt_show_rte(struct cli *c, byte *ia, rte *e, struct rt_show_data *d, ea_list *tmpa) |
cfd46ee4 | 2387 | { |
6887f409 | 2388 | byte from[STD_ADDRESS_P_LENGTH+8]; |
c37e7851 | 2389 | byte tm[TM_DATETIME_BUFFER_SIZE], info[256]; |
cfd46ee4 | 2390 | rta *a = e->attrs; |
5a56f27c | 2391 | int primary = (e->net->routes == e); |
32f95476 | 2392 | int sync_error = (e->net->n.flags & KRF_SYNC_ERROR); |
094d2bdb | 2393 | void (*get_route_info)(struct rte *, byte *buf, struct ea_list *attrs); |
7e95c05d | 2394 | struct mpnh *nh; |
cfd46ee4 | 2395 | |
c37e7851 | 2396 | tm_format_datetime(tm, &config->tf_route, e->lastmod); |
730f2e2c MM |
2397 | if (ipa_nonzero(a->from) && !ipa_equal(a->from, a->gw)) |
2398 | bsprintf(from, " from %I", a->from); | |
2399 | else | |
2400 | from[0] = 0; | |
094d2bdb OZ |
2401 | |
2402 | get_route_info = a->src->proto->proto->get_route_info; | |
2403 | if (get_route_info || d->verbose) | |
ce1da96e MM |
2404 | { |
2405 | /* Need to normalize the extended attributes */ | |
2406 | ea_list *t = tmpa; | |
2407 | t = ea_append(t, a->eattrs); | |
2408 | tmpa = alloca(ea_scan(t)); | |
2409 | ea_merge(t, tmpa); | |
2f711231 | 2410 | ea_sort(tmpa); |
ce1da96e | 2411 | } |
094d2bdb OZ |
2412 | if (get_route_info) |
2413 | get_route_info(e, info, tmpa); | |
730f2e2c MM |
2414 | else |
2415 | bsprintf(info, " (%d)", e->pref); | |
6887f409 | 2416 | cli_printf(c, -1007, "%-18s %s [%s %s%s]%s%s", ia, rt_format_via(e), a->src->proto->name, |
32f95476 | 2417 | tm, from, primary ? (sync_error ? " !" : " *") : "", info); |
7e95c05d OZ |
2418 | for (nh = a->nexthops; nh; nh = nh->next) |
2419 | cli_printf(c, -1007, "\tvia %I on %s weight %d", nh->gw, nh->iface->name, nh->weight + 1); | |
730f2e2c | 2420 | if (d->verbose) |
ce1da96e | 2421 | rta_show(c, a, tmpa); |
730f2e2c MM |
2422 | } |
2423 | ||
2424 | static void | |
2425 | rt_show_net(struct cli *c, net *n, struct rt_show_data *d) | |
2426 | { | |
2427 | rte *e, *ee; | |
2428 | byte ia[STD_ADDRESS_P_LENGTH+8]; | |
c865cae3 OZ |
2429 | struct ea_list *tmpa; |
2430 | struct announce_hook *a = NULL; | |
2431 | int first = 1; | |
2432 | int pass = 0; | |
730f2e2c MM |
2433 | |
2434 | bsprintf(ia, "%I/%d", n->n.prefix, n->n.pxlen); | |
cf98be7b | 2435 | |
c865cae3 OZ |
2436 | if (d->export_mode) |
2437 | { | |
7aa80901 OZ |
2438 | if (! d->export_protocol->rt_notify) |
2439 | return; | |
2440 | ||
c865cae3 OZ |
2441 | a = proto_find_announce_hook(d->export_protocol, d->table); |
2442 | if (!a) | |
2443 | return; | |
2444 | } | |
2445 | ||
2446 | for (e = n->routes; e; e = e->next) | |
730f2e2c | 2447 | { |
15550957 | 2448 | if (rte_is_filtered(e) != d->filtered) |
cf98be7b OZ |
2449 | continue; |
2450 | ||
23693958 | 2451 | d->rt_counter++; |
c865cae3 OZ |
2452 | d->net_counter += first; |
2453 | first = 0; | |
2454 | ||
2455 | if (pass) | |
2456 | continue; | |
2457 | ||
730f2e2c MM |
2458 | ee = e; |
2459 | rte_update_lock(); /* We use the update buffer for filtering */ | |
094d2bdb | 2460 | tmpa = make_tmp_attrs(e, rte_update_pool); |
c865cae3 | 2461 | |
8d9eef17 OZ |
2462 | /* Special case for merged export */ |
2463 | if ((d->export_mode == RSEM_EXPORT) && (d->export_protocol->accept_ra_types == RA_MERGED)) | |
2464 | { | |
2465 | rte *rt_free; | |
2466 | e = rt_export_merged(a, n, &rt_free, &tmpa, 1); | |
2467 | pass = 1; | |
2468 | ||
2469 | if (!e) | |
2470 | { e = ee; goto skip; } | |
2471 | } | |
2472 | else if (d->export_mode) | |
ce1da96e | 2473 | { |
c865cae3 OZ |
2474 | struct proto *ep = d->export_protocol; |
2475 | int ic = ep->import_control ? ep->import_control(ep, &e, &tmpa, rte_update_pool) : 0; | |
2476 | ||
8d9eef17 | 2477 | if (ep->accept_ra_types == RA_OPTIMAL || ep->accept_ra_types == RA_MERGED) |
c865cae3 OZ |
2478 | pass = 1; |
2479 | ||
2480 | if (ic < 0) | |
2481 | goto skip; | |
2482 | ||
7aa80901 | 2483 | if (d->export_mode > RSEM_PREEXPORT) |
ce1da96e | 2484 | { |
c865cae3 OZ |
2485 | /* |
2486 | * FIXME - This shows what should be exported according to current | |
2487 | * filters, but not what was really exported. 'configure soft' | |
2488 | * command may change the export filter and do not update routes. | |
2489 | */ | |
7aa80901 OZ |
2490 | int do_export = (ic > 0) || |
2491 | (f_run(a->out_filter, &e, &tmpa, rte_update_pool, FF_FORCE_TMPATTR) <= F_ACCEPT); | |
c865cae3 | 2492 | |
7aa80901 | 2493 | if (do_export != (d->export_mode == RSEM_EXPORT)) |
c865cae3 OZ |
2494 | goto skip; |
2495 | ||
7aa80901 | 2496 | if ((d->export_mode == RSEM_EXPORT) && (ep->accept_ra_types == RA_ACCEPTED)) |
c865cae3 | 2497 | pass = 1; |
ce1da96e MM |
2498 | } |
2499 | } | |
c865cae3 OZ |
2500 | |
2501 | if (d->show_protocol && (d->show_protocol != e->attrs->src->proto)) | |
2502 | goto skip; | |
2503 | ||
2504 | if (f_run(d->filter, &e, &tmpa, rte_update_pool, FF_FORCE_TMPATTR) > F_ACCEPT) | |
2505 | goto skip; | |
2506 | ||
2507 | d->show_counter++; | |
2508 | if (d->stats < 2) | |
2509 | rt_show_rte(c, ia, e, d, tmpa); | |
2510 | ia[0] = 0; | |
2511 | ||
2512 | skip: | |
730f2e2c | 2513 | if (e != ee) |
5e9bdac2 OZ |
2514 | { |
2515 | rte_free(e); | |
2516 | e = ee; | |
2517 | } | |
730f2e2c | 2518 | rte_update_unlock(); |
c865cae3 | 2519 | |
0117d004 | 2520 | if (d->primary_only) |
ce1da96e | 2521 | break; |
730f2e2c MM |
2522 | } |
2523 | } | |
2524 | ||
2525 | static void | |
2526 | rt_show_cont(struct cli *c) | |
2527 | { | |
2528 | struct rt_show_data *d = c->rover; | |
f098e072 MM |
2529 | #ifdef DEBUGGING |
2530 | unsigned max = 4; | |
2531 | #else | |
2532 | unsigned max = 64; | |
2533 | #endif | |
730f2e2c MM |
2534 | struct fib *fib = &d->table->fib; |
2535 | struct fib_iterator *it = &d->fit; | |
2536 | ||
2537 | FIB_ITERATE_START(fib, it, f) | |
2538 | { | |
2539 | net *n = (net *) f; | |
ce1da96e MM |
2540 | if (d->running_on_config && d->running_on_config != config) |
2541 | { | |
2542 | cli_printf(c, 8004, "Stopped due to reconfiguration"); | |
2543 | goto done; | |
2544 | } | |
0c791f87 | 2545 | if (d->export_protocol && (d->export_protocol->export_state == ES_DOWN)) |
ce1da96e MM |
2546 | { |
2547 | cli_printf(c, 8005, "Protocol is down"); | |
2548 | goto done; | |
2549 | } | |
730f2e2c MM |
2550 | if (!max--) |
2551 | { | |
2552 | FIB_ITERATE_PUT(it, f); | |
2553 | return; | |
2554 | } | |
2555 | rt_show_net(c, n, d); | |
2556 | } | |
2557 | FIB_ITERATE_END(f); | |
23693958 MM |
2558 | if (d->stats) |
2559 | cli_printf(c, 14, "%d of %d routes for %d networks", d->show_counter, d->rt_counter, d->net_counter); | |
2560 | else | |
2561 | cli_printf(c, 0, ""); | |
ce1da96e | 2562 | done: |
730f2e2c MM |
2563 | c->cont = c->cleanup = NULL; |
2564 | } | |
2565 | ||
2566 | static void | |
2567 | rt_show_cleanup(struct cli *c) | |
2568 | { | |
2569 | struct rt_show_data *d = c->rover; | |
2570 | ||
2571 | /* Unlink the iterator */ | |
2572 | fit_get(&d->table->fib, &d->fit); | |
2573 | } | |
2574 | ||
2575 | void | |
2576 | rt_show(struct rt_show_data *d) | |
2577 | { | |
730f2e2c MM |
2578 | net *n; |
2579 | ||
e667622a | 2580 | /* Default is either a master table or a table related to a respective protocol */ |
c865cae3 OZ |
2581 | if (!d->table && d->export_protocol) d->table = d->export_protocol->table; |
2582 | if (!d->table && d->show_protocol) d->table = d->show_protocol->table; | |
e667622a OF |
2583 | if (!d->table) d->table = config->master_rtc->table; |
2584 | ||
c865cae3 OZ |
2585 | /* Filtered routes are neither exported nor have sensible ordering */ |
2586 | if (d->filtered && (d->export_mode || d->primary_only)) | |
2587 | cli_msg(0, ""); | |
2588 | ||
730f2e2c MM |
2589 | if (d->pxlen == 256) |
2590 | { | |
2591 | FIB_ITERATE_INIT(&d->fit, &d->table->fib); | |
2592 | this_cli->cont = rt_show_cont; | |
2593 | this_cli->cleanup = rt_show_cleanup; | |
2594 | this_cli->rover = d; | |
2595 | } | |
2596 | else | |
2597 | { | |
9449c91a | 2598 | if (d->show_for) |
d1e146f2 | 2599 | n = net_route(d->table, d->prefix, d->pxlen); |
9449c91a | 2600 | else |
d1e146f2 | 2601 | n = net_find(d->table, d->prefix, d->pxlen); |
0da562a7 | 2602 | |
730f2e2c | 2603 | if (n) |
0da562a7 OZ |
2604 | rt_show_net(this_cli, n, d); |
2605 | ||
2606 | if (d->rt_counter) | |
2607 | cli_msg(0, ""); | |
730f2e2c MM |
2608 | else |
2609 | cli_msg(8001, "Network not in table"); | |
2610 | } | |
2611 | } | |
3ce8c610 MM |
2612 | |
2613 | /* | |
2614 | * Documentation for functions declared inline in route.h | |
2615 | */ | |
2616 | #if 0 | |
2617 | ||
2618 | /** | |
2619 | * net_find - find a network entry | |
2620 | * @tab: a routing table | |
2621 | * @addr: address of the network | |
2622 | * @len: length of the network prefix | |
2623 | * | |
2624 | * net_find() looks up the given network in routing table @tab and | |
2625 | * returns a pointer to its &net entry or %NULL if no such network | |
2626 | * exists. | |
2627 | */ | |
2628 | static inline net *net_find(rtable *tab, ip_addr addr, unsigned len) | |
2629 | { DUMMY; } | |
2630 | ||
2631 | /** | |
2632 | * net_get - obtain a network entry | |
2633 | * @tab: a routing table | |
2634 | * @addr: address of the network | |
2635 | * @len: length of the network prefix | |
2636 | * | |
2637 | * net_get() looks up the given network in routing table @tab and | |
2638 | * returns a pointer to its &net entry. If no such entry exists, it's | |
2639 | * created. | |
2640 | */ | |
2641 | static inline net *net_get(rtable *tab, ip_addr addr, unsigned len) | |
2642 | { DUMMY; } | |
2643 | ||
2644 | /** | |
2645 | * rte_cow - copy a route for writing | |
2646 | * @r: a route entry to be copied | |
2647 | * | |
2648 | * rte_cow() takes a &rte and prepares it for modification. The exact action | |
2649 | * taken depends on the flags of the &rte -- if it's a temporary entry, it's | |
2650 | * just returned unchanged, else a new temporary entry with the same contents | |
2651 | * is created. | |
2652 | * | |
2653 | * The primary use of this function is inside the filter machinery -- when | |
2654 | * a filter wants to modify &rte contents (to change the preference or to | |
2655 | * attach another set of attributes), it must ensure that the &rte is not | |
2656 | * shared with anyone else (and especially that it isn't stored in any routing | |
2657 | * table). | |
2658 | * | |
2e9b2421 | 2659 | * Result: a pointer to the new writable &rte. |
3ce8c610 MM |
2660 | */ |
2661 | static inline rte * rte_cow(rte *r) | |
2662 | { DUMMY; } | |
2663 | ||
2664 | #endif |