Commit | Line | Data |
---|---|---|
1da177e4 | 1 | /* |
1ab1457c | 2 | * Linux INET6 implementation |
1da177e4 LT |
3 | * Forwarding Information Database |
4 | * | |
5 | * Authors: | |
1ab1457c | 6 | * Pedro Roque <roque@di.fc.ul.pt> |
1da177e4 LT |
7 | * |
8 | * $Id: ip6_fib.c,v 1.25 2001/10/31 21:55:55 davem Exp $ | |
9 | * | |
10 | * This program is free software; you can redistribute it and/or | |
11 | * modify it under the terms of the GNU General Public License | |
12 | * as published by the Free Software Foundation; either version | |
13 | * 2 of the License, or (at your option) any later version. | |
14 | */ | |
15 | ||
16 | /* | |
17 | * Changes: | |
18 | * Yuji SEKIYA @USAGI: Support default route on router node; | |
19 | * remove ip6_null_entry from the top of | |
20 | * routing table. | |
c0bece9f | 21 | * Ville Nuorvala: Fixed routing subtrees. |
1da177e4 | 22 | */ |
1da177e4 LT |
23 | #include <linux/errno.h> |
24 | #include <linux/types.h> | |
25 | #include <linux/net.h> | |
26 | #include <linux/route.h> | |
27 | #include <linux/netdevice.h> | |
28 | #include <linux/in6.h> | |
29 | #include <linux/init.h> | |
c71099ac | 30 | #include <linux/list.h> |
1da177e4 LT |
31 | |
32 | #ifdef CONFIG_PROC_FS | |
33 | #include <linux/proc_fs.h> | |
34 | #endif | |
35 | ||
36 | #include <net/ipv6.h> | |
37 | #include <net/ndisc.h> | |
38 | #include <net/addrconf.h> | |
39 | ||
40 | #include <net/ip6_fib.h> | |
41 | #include <net/ip6_route.h> | |
42 | ||
43 | #define RT6_DEBUG 2 | |
44 | ||
45 | #if RT6_DEBUG >= 3 | |
46 | #define RT6_TRACE(x...) printk(KERN_DEBUG x) | |
47 | #else | |
48 | #define RT6_TRACE(x...) do { ; } while (0) | |
49 | #endif | |
50 | ||
51 | struct rt6_statistics rt6_stats; | |
52 | ||
e18b890b | 53 | static struct kmem_cache * fib6_node_kmem __read_mostly; |
1da177e4 LT |
54 | |
55 | enum fib_walk_state_t | |
56 | { | |
57 | #ifdef CONFIG_IPV6_SUBTREES | |
58 | FWS_S, | |
59 | #endif | |
60 | FWS_L, | |
61 | FWS_R, | |
62 | FWS_C, | |
63 | FWS_U | |
64 | }; | |
65 | ||
66 | struct fib6_cleaner_t | |
67 | { | |
68 | struct fib6_walker_t w; | |
69 | int (*func)(struct rt6_info *, void *arg); | |
70 | void *arg; | |
71 | }; | |
72 | ||
90d41122 | 73 | static DEFINE_RWLOCK(fib6_walker_lock); |
1da177e4 LT |
74 | |
75 | #ifdef CONFIG_IPV6_SUBTREES | |
76 | #define FWS_INIT FWS_S | |
1da177e4 LT |
77 | #else |
78 | #define FWS_INIT FWS_L | |
1da177e4 LT |
79 | #endif |
80 | ||
81 | static void fib6_prune_clones(struct fib6_node *fn, struct rt6_info *rt); | |
66729e18 | 82 | static struct rt6_info * fib6_find_prefix(struct fib6_node *fn); |
1da177e4 | 83 | static struct fib6_node * fib6_repair_tree(struct fib6_node *fn); |
90d41122 AB |
84 | static int fib6_walk(struct fib6_walker_t *w); |
85 | static int fib6_walk_continue(struct fib6_walker_t *w); | |
1da177e4 LT |
86 | |
87 | /* | |
88 | * A routing update causes an increase of the serial number on the | |
89 | * affected subtree. This allows for cached routes to be asynchronously | |
90 | * tested when modifications are made to the destination cache as a | |
91 | * result of redirects, path MTU changes, etc. | |
92 | */ | |
93 | ||
94 | static __u32 rt_sernum; | |
95 | ||
8d06afab | 96 | static DEFINE_TIMER(ip6_fib_timer, fib6_run_gc, 0, 0); |
1da177e4 | 97 | |
90d41122 | 98 | static struct fib6_walker_t fib6_walker_list = { |
1da177e4 | 99 | .prev = &fib6_walker_list, |
1ab1457c | 100 | .next = &fib6_walker_list, |
1da177e4 LT |
101 | }; |
102 | ||
103 | #define FOR_WALKERS(w) for ((w)=fib6_walker_list.next; (w) != &fib6_walker_list; (w)=(w)->next) | |
104 | ||
90d41122 AB |
105 | static inline void fib6_walker_link(struct fib6_walker_t *w) |
106 | { | |
107 | write_lock_bh(&fib6_walker_lock); | |
108 | w->next = fib6_walker_list.next; | |
109 | w->prev = &fib6_walker_list; | |
110 | w->next->prev = w; | |
111 | w->prev->next = w; | |
112 | write_unlock_bh(&fib6_walker_lock); | |
113 | } | |
114 | ||
115 | static inline void fib6_walker_unlink(struct fib6_walker_t *w) | |
116 | { | |
117 | write_lock_bh(&fib6_walker_lock); | |
118 | w->next->prev = w->prev; | |
119 | w->prev->next = w->next; | |
120 | w->prev = w->next = w; | |
121 | write_unlock_bh(&fib6_walker_lock); | |
122 | } | |
1da177e4 LT |
123 | static __inline__ u32 fib6_new_sernum(void) |
124 | { | |
125 | u32 n = ++rt_sernum; | |
126 | if ((__s32)n <= 0) | |
127 | rt_sernum = n = 1; | |
128 | return n; | |
129 | } | |
130 | ||
131 | /* | |
132 | * Auxiliary address test functions for the radix tree. | |
133 | * | |
1ab1457c | 134 | * These assume a 32bit processor (although it will work on |
1da177e4 LT |
135 | * 64bit processors) |
136 | */ | |
137 | ||
138 | /* | |
139 | * test bit | |
140 | */ | |
141 | ||
e69a4adc | 142 | static __inline__ __be32 addr_bit_set(void *token, int fn_bit) |
1da177e4 | 143 | { |
e69a4adc | 144 | __be32 *addr = token; |
1da177e4 LT |
145 | |
146 | return htonl(1 << ((~fn_bit)&0x1F)) & addr[fn_bit>>5]; | |
147 | } | |
148 | ||
1da177e4 LT |
149 | static __inline__ struct fib6_node * node_alloc(void) |
150 | { | |
151 | struct fib6_node *fn; | |
152 | ||
c3762229 | 153 | fn = kmem_cache_zalloc(fib6_node_kmem, GFP_ATOMIC); |
1da177e4 LT |
154 | |
155 | return fn; | |
156 | } | |
157 | ||
158 | static __inline__ void node_free(struct fib6_node * fn) | |
159 | { | |
160 | kmem_cache_free(fib6_node_kmem, fn); | |
161 | } | |
162 | ||
163 | static __inline__ void rt6_release(struct rt6_info *rt) | |
164 | { | |
165 | if (atomic_dec_and_test(&rt->rt6i_ref)) | |
166 | dst_free(&rt->u.dst); | |
167 | } | |
168 | ||
c71099ac TG |
169 | static struct fib6_table fib6_main_tbl = { |
170 | .tb6_id = RT6_TABLE_MAIN, | |
c71099ac TG |
171 | .tb6_root = { |
172 | .leaf = &ip6_null_entry, | |
173 | .fn_flags = RTN_ROOT | RTN_TL_ROOT | RTN_RTINFO, | |
174 | }, | |
175 | }; | |
176 | ||
177 | #ifdef CONFIG_IPV6_MULTIPLE_TABLES | |
1b43af54 PM |
178 | #define FIB_TABLE_HASHSZ 256 |
179 | #else | |
180 | #define FIB_TABLE_HASHSZ 1 | |
181 | #endif | |
182 | static struct hlist_head fib_table_hash[FIB_TABLE_HASHSZ]; | |
183 | ||
184 | static void fib6_link_table(struct fib6_table *tb) | |
185 | { | |
186 | unsigned int h; | |
187 | ||
375216ad TG |
188 | /* |
189 | * Initialize table lock at a single place to give lockdep a key, | |
190 | * tables aren't visible prior to being linked to the list. | |
191 | */ | |
192 | rwlock_init(&tb->tb6_lock); | |
193 | ||
1b43af54 PM |
194 | h = tb->tb6_id & (FIB_TABLE_HASHSZ - 1); |
195 | ||
196 | /* | |
197 | * No protection necessary, this is the only list mutatation | |
198 | * operation, tables never disappear once they exist. | |
199 | */ | |
200 | hlist_add_head_rcu(&tb->tb6_hlist, &fib_table_hash[h]); | |
201 | } | |
c71099ac | 202 | |
1b43af54 | 203 | #ifdef CONFIG_IPV6_MULTIPLE_TABLES |
101367c2 TG |
204 | static struct fib6_table fib6_local_tbl = { |
205 | .tb6_id = RT6_TABLE_LOCAL, | |
101367c2 TG |
206 | .tb6_root = { |
207 | .leaf = &ip6_null_entry, | |
208 | .fn_flags = RTN_ROOT | RTN_TL_ROOT | RTN_RTINFO, | |
209 | }, | |
210 | }; | |
211 | ||
c71099ac TG |
212 | static struct fib6_table *fib6_alloc_table(u32 id) |
213 | { | |
214 | struct fib6_table *table; | |
215 | ||
216 | table = kzalloc(sizeof(*table), GFP_ATOMIC); | |
217 | if (table != NULL) { | |
218 | table->tb6_id = id; | |
c71099ac TG |
219 | table->tb6_root.leaf = &ip6_null_entry; |
220 | table->tb6_root.fn_flags = RTN_ROOT | RTN_TL_ROOT | RTN_RTINFO; | |
221 | } | |
222 | ||
223 | return table; | |
224 | } | |
225 | ||
c71099ac TG |
226 | struct fib6_table *fib6_new_table(u32 id) |
227 | { | |
228 | struct fib6_table *tb; | |
229 | ||
230 | if (id == 0) | |
231 | id = RT6_TABLE_MAIN; | |
232 | tb = fib6_get_table(id); | |
233 | if (tb) | |
234 | return tb; | |
235 | ||
236 | tb = fib6_alloc_table(id); | |
237 | if (tb != NULL) | |
238 | fib6_link_table(tb); | |
239 | ||
240 | return tb; | |
241 | } | |
242 | ||
243 | struct fib6_table *fib6_get_table(u32 id) | |
244 | { | |
245 | struct fib6_table *tb; | |
246 | struct hlist_node *node; | |
247 | unsigned int h; | |
248 | ||
249 | if (id == 0) | |
250 | id = RT6_TABLE_MAIN; | |
251 | h = id & (FIB_TABLE_HASHSZ - 1); | |
252 | rcu_read_lock(); | |
253 | hlist_for_each_entry_rcu(tb, node, &fib_table_hash[h], tb6_hlist) { | |
254 | if (tb->tb6_id == id) { | |
255 | rcu_read_unlock(); | |
256 | return tb; | |
257 | } | |
258 | } | |
259 | rcu_read_unlock(); | |
260 | ||
261 | return NULL; | |
262 | } | |
263 | ||
c71099ac TG |
264 | static void __init fib6_tables_init(void) |
265 | { | |
266 | fib6_link_table(&fib6_main_tbl); | |
101367c2 | 267 | fib6_link_table(&fib6_local_tbl); |
c71099ac TG |
268 | } |
269 | ||
270 | #else | |
271 | ||
272 | struct fib6_table *fib6_new_table(u32 id) | |
273 | { | |
274 | return fib6_get_table(id); | |
275 | } | |
276 | ||
277 | struct fib6_table *fib6_get_table(u32 id) | |
278 | { | |
279 | return &fib6_main_tbl; | |
280 | } | |
281 | ||
282 | struct dst_entry *fib6_rule_lookup(struct flowi *fl, int flags, | |
283 | pol_lookup_t lookup) | |
284 | { | |
285 | return (struct dst_entry *) lookup(&fib6_main_tbl, fl, flags); | |
286 | } | |
287 | ||
288 | static void __init fib6_tables_init(void) | |
289 | { | |
1b43af54 | 290 | fib6_link_table(&fib6_main_tbl); |
c71099ac TG |
291 | } |
292 | ||
293 | #endif | |
294 | ||
1b43af54 PM |
295 | static int fib6_dump_node(struct fib6_walker_t *w) |
296 | { | |
297 | int res; | |
298 | struct rt6_info *rt; | |
299 | ||
7cc48263 | 300 | for (rt = w->leaf; rt; rt = rt->u.dst.rt6_next) { |
1b43af54 PM |
301 | res = rt6_dump_route(rt, w->args); |
302 | if (res < 0) { | |
303 | /* Frame is full, suspend walking */ | |
304 | w->leaf = rt; | |
305 | return 1; | |
306 | } | |
307 | BUG_TRAP(res!=0); | |
308 | } | |
309 | w->leaf = NULL; | |
310 | return 0; | |
311 | } | |
312 | ||
313 | static void fib6_dump_end(struct netlink_callback *cb) | |
314 | { | |
315 | struct fib6_walker_t *w = (void*)cb->args[2]; | |
316 | ||
317 | if (w) { | |
318 | cb->args[2] = 0; | |
319 | kfree(w); | |
320 | } | |
321 | cb->done = (void*)cb->args[3]; | |
322 | cb->args[1] = 3; | |
323 | } | |
324 | ||
325 | static int fib6_dump_done(struct netlink_callback *cb) | |
326 | { | |
327 | fib6_dump_end(cb); | |
328 | return cb->done ? cb->done(cb) : 0; | |
329 | } | |
330 | ||
331 | static int fib6_dump_table(struct fib6_table *table, struct sk_buff *skb, | |
332 | struct netlink_callback *cb) | |
333 | { | |
334 | struct fib6_walker_t *w; | |
335 | int res; | |
336 | ||
337 | w = (void *)cb->args[2]; | |
338 | w->root = &table->tb6_root; | |
339 | ||
340 | if (cb->args[4] == 0) { | |
341 | read_lock_bh(&table->tb6_lock); | |
342 | res = fib6_walk(w); | |
343 | read_unlock_bh(&table->tb6_lock); | |
344 | if (res > 0) | |
345 | cb->args[4] = 1; | |
346 | } else { | |
347 | read_lock_bh(&table->tb6_lock); | |
348 | res = fib6_walk_continue(w); | |
349 | read_unlock_bh(&table->tb6_lock); | |
350 | if (res != 0) { | |
351 | if (res < 0) | |
352 | fib6_walker_unlink(w); | |
353 | goto end; | |
354 | } | |
355 | fib6_walker_unlink(w); | |
356 | cb->args[4] = 0; | |
357 | } | |
358 | end: | |
359 | return res; | |
360 | } | |
361 | ||
c127ea2c | 362 | static int inet6_dump_fib(struct sk_buff *skb, struct netlink_callback *cb) |
1b43af54 | 363 | { |
b854272b | 364 | struct net *net = skb->sk->sk_net; |
1b43af54 PM |
365 | unsigned int h, s_h; |
366 | unsigned int e = 0, s_e; | |
367 | struct rt6_rtnl_dump_arg arg; | |
368 | struct fib6_walker_t *w; | |
369 | struct fib6_table *tb; | |
370 | struct hlist_node *node; | |
371 | int res = 0; | |
372 | ||
b854272b DL |
373 | if (net != &init_net) |
374 | return 0; | |
375 | ||
1b43af54 PM |
376 | s_h = cb->args[0]; |
377 | s_e = cb->args[1]; | |
378 | ||
379 | w = (void *)cb->args[2]; | |
380 | if (w == NULL) { | |
381 | /* New dump: | |
382 | * | |
383 | * 1. hook callback destructor. | |
384 | */ | |
385 | cb->args[3] = (long)cb->done; | |
386 | cb->done = fib6_dump_done; | |
387 | ||
388 | /* | |
389 | * 2. allocate and initialize walker. | |
390 | */ | |
391 | w = kzalloc(sizeof(*w), GFP_ATOMIC); | |
392 | if (w == NULL) | |
393 | return -ENOMEM; | |
394 | w->func = fib6_dump_node; | |
395 | cb->args[2] = (long)w; | |
396 | } | |
397 | ||
398 | arg.skb = skb; | |
399 | arg.cb = cb; | |
400 | w->args = &arg; | |
401 | ||
402 | for (h = s_h; h < FIB_TABLE_HASHSZ; h++, s_e = 0) { | |
403 | e = 0; | |
404 | hlist_for_each_entry(tb, node, &fib_table_hash[h], tb6_hlist) { | |
405 | if (e < s_e) | |
406 | goto next; | |
407 | res = fib6_dump_table(tb, skb, cb); | |
408 | if (res != 0) | |
409 | goto out; | |
410 | next: | |
411 | e++; | |
412 | } | |
413 | } | |
414 | out: | |
415 | cb->args[1] = e; | |
416 | cb->args[0] = h; | |
417 | ||
418 | res = res < 0 ? res : skb->len; | |
419 | if (res <= 0) | |
420 | fib6_dump_end(cb); | |
421 | return res; | |
422 | } | |
1da177e4 LT |
423 | |
424 | /* | |
425 | * Routing Table | |
426 | * | |
427 | * return the appropriate node for a routing tree "add" operation | |
428 | * by either creating and inserting or by returning an existing | |
429 | * node. | |
430 | */ | |
431 | ||
432 | static struct fib6_node * fib6_add_1(struct fib6_node *root, void *addr, | |
433 | int addrlen, int plen, | |
434 | int offset) | |
435 | { | |
436 | struct fib6_node *fn, *in, *ln; | |
437 | struct fib6_node *pn = NULL; | |
438 | struct rt6key *key; | |
439 | int bit; | |
1ab1457c | 440 | __be32 dir = 0; |
1da177e4 LT |
441 | __u32 sernum = fib6_new_sernum(); |
442 | ||
443 | RT6_TRACE("fib6_add_1\n"); | |
444 | ||
445 | /* insert node in tree */ | |
446 | ||
447 | fn = root; | |
448 | ||
449 | do { | |
450 | key = (struct rt6key *)((u8 *)fn->leaf + offset); | |
451 | ||
452 | /* | |
453 | * Prefix match | |
454 | */ | |
455 | if (plen < fn->fn_bit || | |
456 | !ipv6_prefix_equal(&key->addr, addr, fn->fn_bit)) | |
457 | goto insert_above; | |
1ab1457c | 458 | |
1da177e4 LT |
459 | /* |
460 | * Exact match ? | |
461 | */ | |
1ab1457c | 462 | |
1da177e4 LT |
463 | if (plen == fn->fn_bit) { |
464 | /* clean up an intermediate node */ | |
465 | if ((fn->fn_flags & RTN_RTINFO) == 0) { | |
466 | rt6_release(fn->leaf); | |
467 | fn->leaf = NULL; | |
468 | } | |
1ab1457c | 469 | |
1da177e4 | 470 | fn->fn_sernum = sernum; |
1ab1457c | 471 | |
1da177e4 LT |
472 | return fn; |
473 | } | |
474 | ||
475 | /* | |
476 | * We have more bits to go | |
477 | */ | |
1ab1457c | 478 | |
1da177e4 LT |
479 | /* Try to walk down on tree. */ |
480 | fn->fn_sernum = sernum; | |
481 | dir = addr_bit_set(addr, fn->fn_bit); | |
482 | pn = fn; | |
483 | fn = dir ? fn->right: fn->left; | |
484 | } while (fn); | |
485 | ||
486 | /* | |
487 | * We walked to the bottom of tree. | |
488 | * Create new leaf node without children. | |
489 | */ | |
490 | ||
491 | ln = node_alloc(); | |
492 | ||
493 | if (ln == NULL) | |
494 | return NULL; | |
495 | ln->fn_bit = plen; | |
1ab1457c | 496 | |
1da177e4 LT |
497 | ln->parent = pn; |
498 | ln->fn_sernum = sernum; | |
499 | ||
500 | if (dir) | |
501 | pn->right = ln; | |
502 | else | |
503 | pn->left = ln; | |
504 | ||
505 | return ln; | |
506 | ||
507 | ||
508 | insert_above: | |
509 | /* | |
1ab1457c | 510 | * split since we don't have a common prefix anymore or |
1da177e4 LT |
511 | * we have a less significant route. |
512 | * we've to insert an intermediate node on the list | |
513 | * this new node will point to the one we need to create | |
514 | * and the current | |
515 | */ | |
516 | ||
517 | pn = fn->parent; | |
518 | ||
519 | /* find 1st bit in difference between the 2 addrs. | |
520 | ||
971f359d | 521 | See comment in __ipv6_addr_diff: bit may be an invalid value, |
1da177e4 LT |
522 | but if it is >= plen, the value is ignored in any case. |
523 | */ | |
1ab1457c | 524 | |
971f359d | 525 | bit = __ipv6_addr_diff(addr, &key->addr, addrlen); |
1da177e4 | 526 | |
1ab1457c YH |
527 | /* |
528 | * (intermediate)[in] | |
1da177e4 LT |
529 | * / \ |
530 | * (new leaf node)[ln] (old node)[fn] | |
531 | */ | |
532 | if (plen > bit) { | |
533 | in = node_alloc(); | |
534 | ln = node_alloc(); | |
1ab1457c | 535 | |
1da177e4 LT |
536 | if (in == NULL || ln == NULL) { |
537 | if (in) | |
538 | node_free(in); | |
539 | if (ln) | |
540 | node_free(ln); | |
541 | return NULL; | |
542 | } | |
543 | ||
1ab1457c YH |
544 | /* |
545 | * new intermediate node. | |
1da177e4 LT |
546 | * RTN_RTINFO will |
547 | * be off since that an address that chooses one of | |
548 | * the branches would not match less specific routes | |
549 | * in the other branch | |
550 | */ | |
551 | ||
552 | in->fn_bit = bit; | |
553 | ||
554 | in->parent = pn; | |
555 | in->leaf = fn->leaf; | |
556 | atomic_inc(&in->leaf->rt6i_ref); | |
557 | ||
558 | in->fn_sernum = sernum; | |
559 | ||
560 | /* update parent pointer */ | |
561 | if (dir) | |
562 | pn->right = in; | |
563 | else | |
564 | pn->left = in; | |
565 | ||
566 | ln->fn_bit = plen; | |
567 | ||
568 | ln->parent = in; | |
569 | fn->parent = in; | |
570 | ||
571 | ln->fn_sernum = sernum; | |
572 | ||
573 | if (addr_bit_set(addr, bit)) { | |
574 | in->right = ln; | |
575 | in->left = fn; | |
576 | } else { | |
577 | in->left = ln; | |
578 | in->right = fn; | |
579 | } | |
580 | } else { /* plen <= bit */ | |
581 | ||
1ab1457c | 582 | /* |
1da177e4 LT |
583 | * (new leaf node)[ln] |
584 | * / \ | |
585 | * (old node)[fn] NULL | |
586 | */ | |
587 | ||
588 | ln = node_alloc(); | |
589 | ||
590 | if (ln == NULL) | |
591 | return NULL; | |
592 | ||
593 | ln->fn_bit = plen; | |
594 | ||
595 | ln->parent = pn; | |
596 | ||
597 | ln->fn_sernum = sernum; | |
1ab1457c | 598 | |
1da177e4 LT |
599 | if (dir) |
600 | pn->right = ln; | |
601 | else | |
602 | pn->left = ln; | |
603 | ||
604 | if (addr_bit_set(&key->addr, plen)) | |
605 | ln->right = fn; | |
606 | else | |
607 | ln->left = fn; | |
608 | ||
609 | fn->parent = ln; | |
610 | } | |
611 | return ln; | |
612 | } | |
613 | ||
614 | /* | |
615 | * Insert routing information in a node. | |
616 | */ | |
617 | ||
618 | static int fib6_add_rt2node(struct fib6_node *fn, struct rt6_info *rt, | |
86872cb5 | 619 | struct nl_info *info) |
1da177e4 LT |
620 | { |
621 | struct rt6_info *iter = NULL; | |
622 | struct rt6_info **ins; | |
623 | ||
624 | ins = &fn->leaf; | |
625 | ||
7cc48263 | 626 | for (iter = fn->leaf; iter; iter=iter->u.dst.rt6_next) { |
1da177e4 LT |
627 | /* |
628 | * Search for duplicates | |
629 | */ | |
630 | ||
631 | if (iter->rt6i_metric == rt->rt6i_metric) { | |
632 | /* | |
633 | * Same priority level | |
634 | */ | |
635 | ||
636 | if (iter->rt6i_dev == rt->rt6i_dev && | |
637 | iter->rt6i_idev == rt->rt6i_idev && | |
638 | ipv6_addr_equal(&iter->rt6i_gateway, | |
639 | &rt->rt6i_gateway)) { | |
640 | if (!(iter->rt6i_flags&RTF_EXPIRES)) | |
641 | return -EEXIST; | |
642 | iter->rt6i_expires = rt->rt6i_expires; | |
643 | if (!(rt->rt6i_flags&RTF_EXPIRES)) { | |
644 | iter->rt6i_flags &= ~RTF_EXPIRES; | |
645 | iter->rt6i_expires = 0; | |
646 | } | |
647 | return -EEXIST; | |
648 | } | |
649 | } | |
650 | ||
651 | if (iter->rt6i_metric > rt->rt6i_metric) | |
652 | break; | |
653 | ||
7cc48263 | 654 | ins = &iter->u.dst.rt6_next; |
1da177e4 LT |
655 | } |
656 | ||
f11e6659 DM |
657 | /* Reset round-robin state, if necessary */ |
658 | if (ins == &fn->leaf) | |
659 | fn->rr_ptr = NULL; | |
660 | ||
1da177e4 LT |
661 | /* |
662 | * insert node | |
663 | */ | |
664 | ||
7cc48263 | 665 | rt->u.dst.rt6_next = iter; |
1da177e4 LT |
666 | *ins = rt; |
667 | rt->rt6i_node = fn; | |
668 | atomic_inc(&rt->rt6i_ref); | |
86872cb5 | 669 | inet6_rt_notify(RTM_NEWROUTE, rt, info); |
1da177e4 LT |
670 | rt6_stats.fib_rt_entries++; |
671 | ||
672 | if ((fn->fn_flags & RTN_RTINFO) == 0) { | |
673 | rt6_stats.fib_route_nodes++; | |
674 | fn->fn_flags |= RTN_RTINFO; | |
675 | } | |
676 | ||
677 | return 0; | |
678 | } | |
679 | ||
680 | static __inline__ void fib6_start_gc(struct rt6_info *rt) | |
681 | { | |
682 | if (ip6_fib_timer.expires == 0 && | |
683 | (rt->rt6i_flags & (RTF_EXPIRES|RTF_CACHE))) | |
4990509f DL |
684 | mod_timer(&ip6_fib_timer, jiffies + |
685 | init_net.ipv6.sysctl.ip6_rt_gc_interval); | |
1da177e4 LT |
686 | } |
687 | ||
688 | void fib6_force_start_gc(void) | |
689 | { | |
690 | if (ip6_fib_timer.expires == 0) | |
4990509f DL |
691 | mod_timer(&ip6_fib_timer, jiffies + |
692 | init_net.ipv6.sysctl.ip6_rt_gc_interval); | |
1da177e4 LT |
693 | } |
694 | ||
695 | /* | |
696 | * Add routing information to the routing tree. | |
697 | * <destination addr>/<source addr> | |
698 | * with source addr info in sub-trees | |
699 | */ | |
700 | ||
86872cb5 | 701 | int fib6_add(struct fib6_node *root, struct rt6_info *rt, struct nl_info *info) |
1da177e4 | 702 | { |
66729e18 | 703 | struct fib6_node *fn, *pn = NULL; |
1da177e4 LT |
704 | int err = -ENOMEM; |
705 | ||
706 | fn = fib6_add_1(root, &rt->rt6i_dst.addr, sizeof(struct in6_addr), | |
707 | rt->rt6i_dst.plen, offsetof(struct rt6_info, rt6i_dst)); | |
708 | ||
709 | if (fn == NULL) | |
710 | goto out; | |
711 | ||
66729e18 YH |
712 | pn = fn; |
713 | ||
1da177e4 LT |
714 | #ifdef CONFIG_IPV6_SUBTREES |
715 | if (rt->rt6i_src.plen) { | |
716 | struct fib6_node *sn; | |
717 | ||
718 | if (fn->subtree == NULL) { | |
719 | struct fib6_node *sfn; | |
720 | ||
721 | /* | |
722 | * Create subtree. | |
723 | * | |
724 | * fn[main tree] | |
725 | * | | |
726 | * sfn[subtree root] | |
727 | * \ | |
728 | * sn[new leaf node] | |
729 | */ | |
730 | ||
731 | /* Create subtree root node */ | |
732 | sfn = node_alloc(); | |
733 | if (sfn == NULL) | |
734 | goto st_failure; | |
735 | ||
736 | sfn->leaf = &ip6_null_entry; | |
737 | atomic_inc(&ip6_null_entry.rt6i_ref); | |
738 | sfn->fn_flags = RTN_ROOT; | |
739 | sfn->fn_sernum = fib6_new_sernum(); | |
740 | ||
741 | /* Now add the first leaf node to new subtree */ | |
742 | ||
743 | sn = fib6_add_1(sfn, &rt->rt6i_src.addr, | |
744 | sizeof(struct in6_addr), rt->rt6i_src.plen, | |
745 | offsetof(struct rt6_info, rt6i_src)); | |
746 | ||
747 | if (sn == NULL) { | |
748 | /* If it is failed, discard just allocated | |
749 | root, and then (in st_failure) stale node | |
750 | in main tree. | |
751 | */ | |
752 | node_free(sfn); | |
753 | goto st_failure; | |
754 | } | |
755 | ||
756 | /* Now link new subtree to main tree */ | |
757 | sfn->parent = fn; | |
758 | fn->subtree = sfn; | |
1da177e4 LT |
759 | } else { |
760 | sn = fib6_add_1(fn->subtree, &rt->rt6i_src.addr, | |
761 | sizeof(struct in6_addr), rt->rt6i_src.plen, | |
762 | offsetof(struct rt6_info, rt6i_src)); | |
763 | ||
764 | if (sn == NULL) | |
765 | goto st_failure; | |
766 | } | |
767 | ||
66729e18 YH |
768 | if (fn->leaf == NULL) { |
769 | fn->leaf = rt; | |
770 | atomic_inc(&rt->rt6i_ref); | |
771 | } | |
1da177e4 LT |
772 | fn = sn; |
773 | } | |
774 | #endif | |
775 | ||
86872cb5 | 776 | err = fib6_add_rt2node(fn, rt, info); |
1da177e4 LT |
777 | |
778 | if (err == 0) { | |
779 | fib6_start_gc(rt); | |
780 | if (!(rt->rt6i_flags&RTF_CACHE)) | |
2285adc1 | 781 | fib6_prune_clones(pn, rt); |
1da177e4 LT |
782 | } |
783 | ||
784 | out: | |
66729e18 YH |
785 | if (err) { |
786 | #ifdef CONFIG_IPV6_SUBTREES | |
787 | /* | |
788 | * If fib6_add_1 has cleared the old leaf pointer in the | |
789 | * super-tree leaf node we have to find a new one for it. | |
790 | */ | |
791 | if (pn != fn && !pn->leaf && !(pn->fn_flags & RTN_RTINFO)) { | |
792 | pn->leaf = fib6_find_prefix(pn); | |
793 | #if RT6_DEBUG >= 2 | |
794 | if (!pn->leaf) { | |
795 | BUG_TRAP(pn->leaf != NULL); | |
796 | pn->leaf = &ip6_null_entry; | |
797 | } | |
798 | #endif | |
799 | atomic_inc(&pn->leaf->rt6i_ref); | |
800 | } | |
801 | #endif | |
1da177e4 | 802 | dst_free(&rt->u.dst); |
66729e18 | 803 | } |
1da177e4 LT |
804 | return err; |
805 | ||
806 | #ifdef CONFIG_IPV6_SUBTREES | |
807 | /* Subtree creation failed, probably main tree node | |
808 | is orphan. If it is, shoot it. | |
809 | */ | |
810 | st_failure: | |
811 | if (fn && !(fn->fn_flags & (RTN_RTINFO|RTN_ROOT))) | |
812 | fib6_repair_tree(fn); | |
813 | dst_free(&rt->u.dst); | |
814 | return err; | |
815 | #endif | |
816 | } | |
817 | ||
818 | /* | |
819 | * Routing tree lookup | |
820 | * | |
821 | */ | |
822 | ||
823 | struct lookup_args { | |
824 | int offset; /* key offset on rt6_info */ | |
825 | struct in6_addr *addr; /* search key */ | |
826 | }; | |
827 | ||
828 | static struct fib6_node * fib6_lookup_1(struct fib6_node *root, | |
829 | struct lookup_args *args) | |
830 | { | |
831 | struct fib6_node *fn; | |
e69a4adc | 832 | __be32 dir; |
1da177e4 | 833 | |
825e288e YH |
834 | if (unlikely(args->offset == 0)) |
835 | return NULL; | |
836 | ||
1da177e4 LT |
837 | /* |
838 | * Descend on a tree | |
839 | */ | |
840 | ||
841 | fn = root; | |
842 | ||
843 | for (;;) { | |
844 | struct fib6_node *next; | |
845 | ||
846 | dir = addr_bit_set(args->addr, fn->fn_bit); | |
847 | ||
848 | next = dir ? fn->right : fn->left; | |
849 | ||
850 | if (next) { | |
851 | fn = next; | |
852 | continue; | |
853 | } | |
854 | ||
855 | break; | |
856 | } | |
857 | ||
3fc5e044 | 858 | while(fn) { |
7fc33165 | 859 | if (FIB6_SUBTREE(fn) || fn->fn_flags & RTN_RTINFO) { |
1da177e4 LT |
860 | struct rt6key *key; |
861 | ||
862 | key = (struct rt6key *) ((u8 *) fn->leaf + | |
863 | args->offset); | |
864 | ||
3fc5e044 YH |
865 | if (ipv6_prefix_equal(&key->addr, args->addr, key->plen)) { |
866 | #ifdef CONFIG_IPV6_SUBTREES | |
867 | if (fn->subtree) | |
868 | fn = fib6_lookup_1(fn->subtree, args + 1); | |
869 | #endif | |
870 | if (!fn || fn->fn_flags & RTN_RTINFO) | |
871 | return fn; | |
872 | } | |
1da177e4 LT |
873 | } |
874 | ||
3fc5e044 YH |
875 | if (fn->fn_flags & RTN_ROOT) |
876 | break; | |
877 | ||
1da177e4 LT |
878 | fn = fn->parent; |
879 | } | |
880 | ||
881 | return NULL; | |
882 | } | |
883 | ||
884 | struct fib6_node * fib6_lookup(struct fib6_node *root, struct in6_addr *daddr, | |
885 | struct in6_addr *saddr) | |
886 | { | |
1da177e4 | 887 | struct fib6_node *fn; |
825e288e YH |
888 | struct lookup_args args[] = { |
889 | { | |
890 | .offset = offsetof(struct rt6_info, rt6i_dst), | |
891 | .addr = daddr, | |
892 | }, | |
1da177e4 | 893 | #ifdef CONFIG_IPV6_SUBTREES |
825e288e YH |
894 | { |
895 | .offset = offsetof(struct rt6_info, rt6i_src), | |
896 | .addr = saddr, | |
897 | }, | |
1da177e4 | 898 | #endif |
825e288e YH |
899 | { |
900 | .offset = 0, /* sentinel */ | |
901 | } | |
902 | }; | |
1da177e4 | 903 | |
fefc2a6c | 904 | fn = fib6_lookup_1(root, daddr ? args : args + 1); |
1da177e4 LT |
905 | |
906 | if (fn == NULL || fn->fn_flags & RTN_TL_ROOT) | |
907 | fn = root; | |
908 | ||
909 | return fn; | |
910 | } | |
911 | ||
912 | /* | |
913 | * Get node with specified destination prefix (and source prefix, | |
914 | * if subtrees are used) | |
915 | */ | |
916 | ||
917 | ||
918 | static struct fib6_node * fib6_locate_1(struct fib6_node *root, | |
919 | struct in6_addr *addr, | |
920 | int plen, int offset) | |
921 | { | |
922 | struct fib6_node *fn; | |
923 | ||
924 | for (fn = root; fn ; ) { | |
925 | struct rt6key *key = (struct rt6key *)((u8 *)fn->leaf + offset); | |
926 | ||
927 | /* | |
928 | * Prefix match | |
929 | */ | |
930 | if (plen < fn->fn_bit || | |
931 | !ipv6_prefix_equal(&key->addr, addr, fn->fn_bit)) | |
932 | return NULL; | |
933 | ||
934 | if (plen == fn->fn_bit) | |
935 | return fn; | |
936 | ||
937 | /* | |
938 | * We have more bits to go | |
939 | */ | |
940 | if (addr_bit_set(addr, fn->fn_bit)) | |
941 | fn = fn->right; | |
942 | else | |
943 | fn = fn->left; | |
944 | } | |
945 | return NULL; | |
946 | } | |
947 | ||
948 | struct fib6_node * fib6_locate(struct fib6_node *root, | |
949 | struct in6_addr *daddr, int dst_len, | |
950 | struct in6_addr *saddr, int src_len) | |
951 | { | |
952 | struct fib6_node *fn; | |
953 | ||
954 | fn = fib6_locate_1(root, daddr, dst_len, | |
955 | offsetof(struct rt6_info, rt6i_dst)); | |
956 | ||
957 | #ifdef CONFIG_IPV6_SUBTREES | |
958 | if (src_len) { | |
959 | BUG_TRAP(saddr!=NULL); | |
3fc5e044 YH |
960 | if (fn && fn->subtree) |
961 | fn = fib6_locate_1(fn->subtree, saddr, src_len, | |
1da177e4 LT |
962 | offsetof(struct rt6_info, rt6i_src)); |
963 | } | |
964 | #endif | |
965 | ||
966 | if (fn && fn->fn_flags&RTN_RTINFO) | |
967 | return fn; | |
968 | ||
969 | return NULL; | |
970 | } | |
971 | ||
972 | ||
973 | /* | |
974 | * Deletion | |
975 | * | |
976 | */ | |
977 | ||
978 | static struct rt6_info * fib6_find_prefix(struct fib6_node *fn) | |
979 | { | |
980 | if (fn->fn_flags&RTN_ROOT) | |
981 | return &ip6_null_entry; | |
982 | ||
983 | while(fn) { | |
984 | if(fn->left) | |
985 | return fn->left->leaf; | |
986 | ||
987 | if(fn->right) | |
988 | return fn->right->leaf; | |
989 | ||
7fc33165 | 990 | fn = FIB6_SUBTREE(fn); |
1da177e4 LT |
991 | } |
992 | return NULL; | |
993 | } | |
994 | ||
995 | /* | |
996 | * Called to trim the tree of intermediate nodes when possible. "fn" | |
997 | * is the node we want to try and remove. | |
998 | */ | |
999 | ||
1000 | static struct fib6_node * fib6_repair_tree(struct fib6_node *fn) | |
1001 | { | |
1002 | int children; | |
1003 | int nstate; | |
1004 | struct fib6_node *child, *pn; | |
1005 | struct fib6_walker_t *w; | |
1006 | int iter = 0; | |
1007 | ||
1008 | for (;;) { | |
1009 | RT6_TRACE("fixing tree: plen=%d iter=%d\n", fn->fn_bit, iter); | |
1010 | iter++; | |
1011 | ||
1012 | BUG_TRAP(!(fn->fn_flags&RTN_RTINFO)); | |
1013 | BUG_TRAP(!(fn->fn_flags&RTN_TL_ROOT)); | |
1014 | BUG_TRAP(fn->leaf==NULL); | |
1015 | ||
1016 | children = 0; | |
1017 | child = NULL; | |
1018 | if (fn->right) child = fn->right, children |= 1; | |
1019 | if (fn->left) child = fn->left, children |= 2; | |
1020 | ||
7fc33165 | 1021 | if (children == 3 || FIB6_SUBTREE(fn) |
1da177e4 LT |
1022 | #ifdef CONFIG_IPV6_SUBTREES |
1023 | /* Subtree root (i.e. fn) may have one child */ | |
1024 | || (children && fn->fn_flags&RTN_ROOT) | |
1025 | #endif | |
1026 | ) { | |
1027 | fn->leaf = fib6_find_prefix(fn); | |
1028 | #if RT6_DEBUG >= 2 | |
1029 | if (fn->leaf==NULL) { | |
1030 | BUG_TRAP(fn->leaf); | |
1031 | fn->leaf = &ip6_null_entry; | |
1032 | } | |
1033 | #endif | |
1034 | atomic_inc(&fn->leaf->rt6i_ref); | |
1035 | return fn->parent; | |
1036 | } | |
1037 | ||
1038 | pn = fn->parent; | |
1039 | #ifdef CONFIG_IPV6_SUBTREES | |
7fc33165 | 1040 | if (FIB6_SUBTREE(pn) == fn) { |
1da177e4 | 1041 | BUG_TRAP(fn->fn_flags&RTN_ROOT); |
7fc33165 | 1042 | FIB6_SUBTREE(pn) = NULL; |
1da177e4 LT |
1043 | nstate = FWS_L; |
1044 | } else { | |
1045 | BUG_TRAP(!(fn->fn_flags&RTN_ROOT)); | |
1046 | #endif | |
1047 | if (pn->right == fn) pn->right = child; | |
1048 | else if (pn->left == fn) pn->left = child; | |
1049 | #if RT6_DEBUG >= 2 | |
1050 | else BUG_TRAP(0); | |
1051 | #endif | |
1052 | if (child) | |
1053 | child->parent = pn; | |
1054 | nstate = FWS_R; | |
1055 | #ifdef CONFIG_IPV6_SUBTREES | |
1056 | } | |
1057 | #endif | |
1058 | ||
1059 | read_lock(&fib6_walker_lock); | |
1060 | FOR_WALKERS(w) { | |
1061 | if (child == NULL) { | |
1062 | if (w->root == fn) { | |
1063 | w->root = w->node = NULL; | |
1064 | RT6_TRACE("W %p adjusted by delroot 1\n", w); | |
1065 | } else if (w->node == fn) { | |
1066 | RT6_TRACE("W %p adjusted by delnode 1, s=%d/%d\n", w, w->state, nstate); | |
1067 | w->node = pn; | |
1068 | w->state = nstate; | |
1069 | } | |
1070 | } else { | |
1071 | if (w->root == fn) { | |
1072 | w->root = child; | |
1073 | RT6_TRACE("W %p adjusted by delroot 2\n", w); | |
1074 | } | |
1075 | if (w->node == fn) { | |
1076 | w->node = child; | |
1077 | if (children&2) { | |
1078 | RT6_TRACE("W %p adjusted by delnode 2, s=%d\n", w, w->state); | |
1079 | w->state = w->state>=FWS_R ? FWS_U : FWS_INIT; | |
1080 | } else { | |
1081 | RT6_TRACE("W %p adjusted by delnode 2, s=%d\n", w, w->state); | |
1082 | w->state = w->state>=FWS_C ? FWS_U : FWS_INIT; | |
1083 | } | |
1084 | } | |
1085 | } | |
1086 | } | |
1087 | read_unlock(&fib6_walker_lock); | |
1088 | ||
1089 | node_free(fn); | |
7fc33165 | 1090 | if (pn->fn_flags&RTN_RTINFO || FIB6_SUBTREE(pn)) |
1da177e4 LT |
1091 | return pn; |
1092 | ||
1093 | rt6_release(pn->leaf); | |
1094 | pn->leaf = NULL; | |
1095 | fn = pn; | |
1096 | } | |
1097 | } | |
1098 | ||
1099 | static void fib6_del_route(struct fib6_node *fn, struct rt6_info **rtp, | |
86872cb5 | 1100 | struct nl_info *info) |
1da177e4 LT |
1101 | { |
1102 | struct fib6_walker_t *w; | |
1103 | struct rt6_info *rt = *rtp; | |
1104 | ||
1105 | RT6_TRACE("fib6_del_route\n"); | |
1106 | ||
1107 | /* Unlink it */ | |
7cc48263 | 1108 | *rtp = rt->u.dst.rt6_next; |
1da177e4 LT |
1109 | rt->rt6i_node = NULL; |
1110 | rt6_stats.fib_rt_entries--; | |
1111 | rt6_stats.fib_discarded_routes++; | |
1112 | ||
f11e6659 DM |
1113 | /* Reset round-robin state, if necessary */ |
1114 | if (fn->rr_ptr == rt) | |
1115 | fn->rr_ptr = NULL; | |
1116 | ||
1da177e4 LT |
1117 | /* Adjust walkers */ |
1118 | read_lock(&fib6_walker_lock); | |
1119 | FOR_WALKERS(w) { | |
1120 | if (w->state == FWS_C && w->leaf == rt) { | |
1121 | RT6_TRACE("walker %p adjusted by delroute\n", w); | |
7cc48263 | 1122 | w->leaf = rt->u.dst.rt6_next; |
1da177e4 LT |
1123 | if (w->leaf == NULL) |
1124 | w->state = FWS_U; | |
1125 | } | |
1126 | } | |
1127 | read_unlock(&fib6_walker_lock); | |
1128 | ||
7cc48263 | 1129 | rt->u.dst.rt6_next = NULL; |
1da177e4 | 1130 | |
1da177e4 LT |
1131 | /* If it was last route, expunge its radix tree node */ |
1132 | if (fn->leaf == NULL) { | |
1133 | fn->fn_flags &= ~RTN_RTINFO; | |
1134 | rt6_stats.fib_route_nodes--; | |
1135 | fn = fib6_repair_tree(fn); | |
1136 | } | |
1137 | ||
1138 | if (atomic_read(&rt->rt6i_ref) != 1) { | |
1139 | /* This route is used as dummy address holder in some split | |
1140 | * nodes. It is not leaked, but it still holds other resources, | |
1141 | * which must be released in time. So, scan ascendant nodes | |
1142 | * and replace dummy references to this route with references | |
1143 | * to still alive ones. | |
1144 | */ | |
1145 | while (fn) { | |
1146 | if (!(fn->fn_flags&RTN_RTINFO) && fn->leaf == rt) { | |
1147 | fn->leaf = fib6_find_prefix(fn); | |
1148 | atomic_inc(&fn->leaf->rt6i_ref); | |
1149 | rt6_release(rt); | |
1150 | } | |
1151 | fn = fn->parent; | |
1152 | } | |
1153 | /* No more references are possible at this point. */ | |
2df96af0 | 1154 | BUG_ON(atomic_read(&rt->rt6i_ref) != 1); |
1da177e4 LT |
1155 | } |
1156 | ||
86872cb5 | 1157 | inet6_rt_notify(RTM_DELROUTE, rt, info); |
1da177e4 LT |
1158 | rt6_release(rt); |
1159 | } | |
1160 | ||
86872cb5 | 1161 | int fib6_del(struct rt6_info *rt, struct nl_info *info) |
1da177e4 LT |
1162 | { |
1163 | struct fib6_node *fn = rt->rt6i_node; | |
1164 | struct rt6_info **rtp; | |
1165 | ||
1166 | #if RT6_DEBUG >= 2 | |
1167 | if (rt->u.dst.obsolete>0) { | |
1168 | BUG_TRAP(fn==NULL); | |
1169 | return -ENOENT; | |
1170 | } | |
1171 | #endif | |
1172 | if (fn == NULL || rt == &ip6_null_entry) | |
1173 | return -ENOENT; | |
1174 | ||
1175 | BUG_TRAP(fn->fn_flags&RTN_RTINFO); | |
1176 | ||
150730d5 YH |
1177 | if (!(rt->rt6i_flags&RTF_CACHE)) { |
1178 | struct fib6_node *pn = fn; | |
1179 | #ifdef CONFIG_IPV6_SUBTREES | |
1180 | /* clones of this route might be in another subtree */ | |
1181 | if (rt->rt6i_src.plen) { | |
1182 | while (!(pn->fn_flags&RTN_ROOT)) | |
1183 | pn = pn->parent; | |
1184 | pn = pn->parent; | |
1185 | } | |
1186 | #endif | |
1187 | fib6_prune_clones(pn, rt); | |
1188 | } | |
1da177e4 LT |
1189 | |
1190 | /* | |
1191 | * Walk the leaf entries looking for ourself | |
1192 | */ | |
1193 | ||
7cc48263 | 1194 | for (rtp = &fn->leaf; *rtp; rtp = &(*rtp)->u.dst.rt6_next) { |
1da177e4 | 1195 | if (*rtp == rt) { |
86872cb5 | 1196 | fib6_del_route(fn, rtp, info); |
1da177e4 LT |
1197 | return 0; |
1198 | } | |
1199 | } | |
1200 | return -ENOENT; | |
1201 | } | |
1202 | ||
1203 | /* | |
1204 | * Tree traversal function. | |
1205 | * | |
1206 | * Certainly, it is not interrupt safe. | |
1207 | * However, it is internally reenterable wrt itself and fib6_add/fib6_del. | |
1208 | * It means, that we can modify tree during walking | |
1209 | * and use this function for garbage collection, clone pruning, | |
1ab1457c | 1210 | * cleaning tree when a device goes down etc. etc. |
1da177e4 LT |
1211 | * |
1212 | * It guarantees that every node will be traversed, | |
1213 | * and that it will be traversed only once. | |
1214 | * | |
1215 | * Callback function w->func may return: | |
1216 | * 0 -> continue walking. | |
1217 | * positive value -> walking is suspended (used by tree dumps, | |
1218 | * and probably by gc, if it will be split to several slices) | |
1219 | * negative value -> terminate walking. | |
1220 | * | |
1221 | * The function itself returns: | |
1222 | * 0 -> walk is complete. | |
1223 | * >0 -> walk is incomplete (i.e. suspended) | |
1224 | * <0 -> walk is terminated by an error. | |
1225 | */ | |
1226 | ||
90d41122 | 1227 | static int fib6_walk_continue(struct fib6_walker_t *w) |
1da177e4 LT |
1228 | { |
1229 | struct fib6_node *fn, *pn; | |
1230 | ||
1231 | for (;;) { | |
1232 | fn = w->node; | |
1233 | if (fn == NULL) | |
1234 | return 0; | |
1235 | ||
1236 | if (w->prune && fn != w->root && | |
1237 | fn->fn_flags&RTN_RTINFO && w->state < FWS_C) { | |
1238 | w->state = FWS_C; | |
1239 | w->leaf = fn->leaf; | |
1240 | } | |
1241 | switch (w->state) { | |
1242 | #ifdef CONFIG_IPV6_SUBTREES | |
1243 | case FWS_S: | |
7fc33165 YH |
1244 | if (FIB6_SUBTREE(fn)) { |
1245 | w->node = FIB6_SUBTREE(fn); | |
1da177e4 LT |
1246 | continue; |
1247 | } | |
1248 | w->state = FWS_L; | |
1ab1457c | 1249 | #endif |
1da177e4 LT |
1250 | case FWS_L: |
1251 | if (fn->left) { | |
1252 | w->node = fn->left; | |
1253 | w->state = FWS_INIT; | |
1254 | continue; | |
1255 | } | |
1256 | w->state = FWS_R; | |
1257 | case FWS_R: | |
1258 | if (fn->right) { | |
1259 | w->node = fn->right; | |
1260 | w->state = FWS_INIT; | |
1261 | continue; | |
1262 | } | |
1263 | w->state = FWS_C; | |
1264 | w->leaf = fn->leaf; | |
1265 | case FWS_C: | |
1266 | if (w->leaf && fn->fn_flags&RTN_RTINFO) { | |
1267 | int err = w->func(w); | |
1268 | if (err) | |
1269 | return err; | |
1270 | continue; | |
1271 | } | |
1272 | w->state = FWS_U; | |
1273 | case FWS_U: | |
1274 | if (fn == w->root) | |
1275 | return 0; | |
1276 | pn = fn->parent; | |
1277 | w->node = pn; | |
1278 | #ifdef CONFIG_IPV6_SUBTREES | |
7fc33165 | 1279 | if (FIB6_SUBTREE(pn) == fn) { |
1da177e4 LT |
1280 | BUG_TRAP(fn->fn_flags&RTN_ROOT); |
1281 | w->state = FWS_L; | |
1282 | continue; | |
1283 | } | |
1284 | #endif | |
1285 | if (pn->left == fn) { | |
1286 | w->state = FWS_R; | |
1287 | continue; | |
1288 | } | |
1289 | if (pn->right == fn) { | |
1290 | w->state = FWS_C; | |
1291 | w->leaf = w->node->leaf; | |
1292 | continue; | |
1293 | } | |
1294 | #if RT6_DEBUG >= 2 | |
1295 | BUG_TRAP(0); | |
1296 | #endif | |
1297 | } | |
1298 | } | |
1299 | } | |
1300 | ||
90d41122 | 1301 | static int fib6_walk(struct fib6_walker_t *w) |
1da177e4 LT |
1302 | { |
1303 | int res; | |
1304 | ||
1305 | w->state = FWS_INIT; | |
1306 | w->node = w->root; | |
1307 | ||
1308 | fib6_walker_link(w); | |
1309 | res = fib6_walk_continue(w); | |
1310 | if (res <= 0) | |
1311 | fib6_walker_unlink(w); | |
1312 | return res; | |
1313 | } | |
1314 | ||
1315 | static int fib6_clean_node(struct fib6_walker_t *w) | |
1316 | { | |
4d1169c1 DL |
1317 | struct nl_info info = { |
1318 | .nl_net = &init_net, | |
1319 | }; | |
1da177e4 LT |
1320 | int res; |
1321 | struct rt6_info *rt; | |
0a8891a0 | 1322 | struct fib6_cleaner_t *c = container_of(w, struct fib6_cleaner_t, w); |
1da177e4 | 1323 | |
7cc48263 | 1324 | for (rt = w->leaf; rt; rt = rt->u.dst.rt6_next) { |
1da177e4 LT |
1325 | res = c->func(rt, c->arg); |
1326 | if (res < 0) { | |
1327 | w->leaf = rt; | |
528c4ceb | 1328 | res = fib6_del(rt, &info); |
1da177e4 LT |
1329 | if (res) { |
1330 | #if RT6_DEBUG >= 2 | |
1331 | printk(KERN_DEBUG "fib6_clean_node: del failed: rt=%p@%p err=%d\n", rt, rt->rt6i_node, res); | |
1332 | #endif | |
1333 | continue; | |
1334 | } | |
1335 | return 0; | |
1336 | } | |
1337 | BUG_TRAP(res==0); | |
1338 | } | |
1339 | w->leaf = rt; | |
1340 | return 0; | |
1341 | } | |
1342 | ||
1343 | /* | |
1344 | * Convenient frontend to tree walker. | |
1ab1457c | 1345 | * |
1da177e4 LT |
1346 | * func is called on each route. |
1347 | * It may return -1 -> delete this route. | |
1348 | * 0 -> continue walking | |
1349 | * | |
1350 | * prune==1 -> only immediate children of node (certainly, | |
1351 | * ignoring pure split nodes) will be scanned. | |
1352 | */ | |
1353 | ||
8ce11e6a AB |
1354 | static void fib6_clean_tree(struct fib6_node *root, |
1355 | int (*func)(struct rt6_info *, void *arg), | |
1356 | int prune, void *arg) | |
1da177e4 LT |
1357 | { |
1358 | struct fib6_cleaner_t c; | |
1359 | ||
1360 | c.w.root = root; | |
1361 | c.w.func = fib6_clean_node; | |
1362 | c.w.prune = prune; | |
1363 | c.func = func; | |
1364 | c.arg = arg; | |
1365 | ||
1366 | fib6_walk(&c.w); | |
1367 | } | |
1368 | ||
c71099ac TG |
1369 | void fib6_clean_all(int (*func)(struct rt6_info *, void *arg), |
1370 | int prune, void *arg) | |
1371 | { | |
c71099ac | 1372 | struct fib6_table *table; |
1b43af54 PM |
1373 | struct hlist_node *node; |
1374 | unsigned int h; | |
c71099ac | 1375 | |
1b43af54 PM |
1376 | rcu_read_lock(); |
1377 | for (h = 0; h < FIB_TABLE_HASHSZ; h++) { | |
1378 | hlist_for_each_entry_rcu(table, node, &fib_table_hash[h], | |
1379 | tb6_hlist) { | |
c71099ac TG |
1380 | write_lock_bh(&table->tb6_lock); |
1381 | fib6_clean_tree(&table->tb6_root, func, prune, arg); | |
1382 | write_unlock_bh(&table->tb6_lock); | |
1383 | } | |
1384 | } | |
1b43af54 | 1385 | rcu_read_unlock(); |
c71099ac TG |
1386 | } |
1387 | ||
1da177e4 LT |
1388 | static int fib6_prune_clone(struct rt6_info *rt, void *arg) |
1389 | { | |
1390 | if (rt->rt6i_flags & RTF_CACHE) { | |
1391 | RT6_TRACE("pruning clone %p\n", rt); | |
1392 | return -1; | |
1393 | } | |
1394 | ||
1395 | return 0; | |
1396 | } | |
1397 | ||
1398 | static void fib6_prune_clones(struct fib6_node *fn, struct rt6_info *rt) | |
1399 | { | |
1400 | fib6_clean_tree(fn, fib6_prune_clone, 1, rt); | |
1401 | } | |
1402 | ||
1403 | /* | |
1404 | * Garbage collection | |
1405 | */ | |
1406 | ||
1407 | static struct fib6_gc_args | |
1408 | { | |
1409 | int timeout; | |
1410 | int more; | |
1411 | } gc_args; | |
1412 | ||
1413 | static int fib6_age(struct rt6_info *rt, void *arg) | |
1414 | { | |
1415 | unsigned long now = jiffies; | |
1416 | ||
1417 | /* | |
1418 | * check addrconf expiration here. | |
1419 | * Routes are expired even if they are in use. | |
1420 | * | |
1421 | * Also age clones. Note, that clones are aged out | |
1422 | * only if they are not in use now. | |
1423 | */ | |
1424 | ||
1425 | if (rt->rt6i_flags&RTF_EXPIRES && rt->rt6i_expires) { | |
1426 | if (time_after(now, rt->rt6i_expires)) { | |
1427 | RT6_TRACE("expiring %p\n", rt); | |
1da177e4 LT |
1428 | return -1; |
1429 | } | |
1430 | gc_args.more++; | |
1431 | } else if (rt->rt6i_flags & RTF_CACHE) { | |
1432 | if (atomic_read(&rt->u.dst.__refcnt) == 0 && | |
1433 | time_after_eq(now, rt->u.dst.lastuse + gc_args.timeout)) { | |
1434 | RT6_TRACE("aging clone %p\n", rt); | |
1435 | return -1; | |
1436 | } else if ((rt->rt6i_flags & RTF_GATEWAY) && | |
1437 | (!(rt->rt6i_nexthop->flags & NTF_ROUTER))) { | |
1438 | RT6_TRACE("purging route %p via non-router but gateway\n", | |
1439 | rt); | |
1440 | return -1; | |
1441 | } | |
1442 | gc_args.more++; | |
1443 | } | |
1444 | ||
1445 | return 0; | |
1446 | } | |
1447 | ||
1448 | static DEFINE_SPINLOCK(fib6_gc_lock); | |
1449 | ||
1450 | void fib6_run_gc(unsigned long dummy) | |
1451 | { | |
1452 | if (dummy != ~0UL) { | |
1453 | spin_lock_bh(&fib6_gc_lock); | |
4990509f DL |
1454 | gc_args.timeout = dummy ? (int)dummy : |
1455 | init_net.ipv6.sysctl.ip6_rt_gc_interval; | |
1da177e4 LT |
1456 | } else { |
1457 | local_bh_disable(); | |
1458 | if (!spin_trylock(&fib6_gc_lock)) { | |
1459 | mod_timer(&ip6_fib_timer, jiffies + HZ); | |
1460 | local_bh_enable(); | |
1461 | return; | |
1462 | } | |
4990509f | 1463 | gc_args.timeout = init_net.ipv6.sysctl.ip6_rt_gc_interval; |
1da177e4 LT |
1464 | } |
1465 | gc_args.more = 0; | |
1466 | ||
1da177e4 | 1467 | ndisc_dst_gc(&gc_args.more); |
c71099ac | 1468 | fib6_clean_all(fib6_age, 0, NULL); |
1da177e4 LT |
1469 | |
1470 | if (gc_args.more) | |
4990509f DL |
1471 | mod_timer(&ip6_fib_timer, jiffies + |
1472 | init_net.ipv6.sysctl.ip6_rt_gc_interval); | |
1da177e4 LT |
1473 | else { |
1474 | del_timer(&ip6_fib_timer); | |
1475 | ip6_fib_timer.expires = 0; | |
1476 | } | |
1477 | spin_unlock_bh(&fib6_gc_lock); | |
1478 | } | |
1479 | ||
d63bddbe | 1480 | int __init fib6_init(void) |
1da177e4 | 1481 | { |
d63bddbe | 1482 | int ret; |
1da177e4 LT |
1483 | fib6_node_kmem = kmem_cache_create("fib6_nodes", |
1484 | sizeof(struct fib6_node), | |
f845ab6b | 1485 | 0, SLAB_HWCACHE_ALIGN, |
20c2df83 | 1486 | NULL); |
f845ab6b DL |
1487 | if (!fib6_node_kmem) |
1488 | return -ENOMEM; | |
1489 | ||
c71099ac | 1490 | fib6_tables_init(); |
c127ea2c | 1491 | |
d63bddbe DL |
1492 | ret = __rtnl_register(PF_INET6, RTM_GETROUTE, NULL, inet6_dump_fib); |
1493 | if (ret) | |
1494 | goto out_kmem_cache_create; | |
1495 | out: | |
1496 | return ret; | |
1497 | ||
1498 | out_kmem_cache_create: | |
1499 | kmem_cache_destroy(fib6_node_kmem); | |
1500 | goto out; | |
1da177e4 LT |
1501 | } |
1502 | ||
1503 | void fib6_gc_cleanup(void) | |
1504 | { | |
1505 | del_timer(&ip6_fib_timer); | |
1506 | kmem_cache_destroy(fib6_node_kmem); | |
1507 | } |