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 | 7 | * |
1da177e4 LT |
8 | * This program is free software; you can redistribute it and/or |
9 | * modify it under the terms of the GNU General Public License | |
10 | * as published by the Free Software Foundation; either version | |
11 | * 2 of the License, or (at your option) any later version. | |
12 | */ | |
13 | ||
14 | /* | |
15 | * Changes: | |
16 | * Yuji SEKIYA @USAGI: Support default route on router node; | |
17 | * remove ip6_null_entry from the top of | |
18 | * routing table. | |
c0bece9f | 19 | * Ville Nuorvala: Fixed routing subtrees. |
1da177e4 | 20 | */ |
1da177e4 LT |
21 | #include <linux/errno.h> |
22 | #include <linux/types.h> | |
23 | #include <linux/net.h> | |
24 | #include <linux/route.h> | |
25 | #include <linux/netdevice.h> | |
26 | #include <linux/in6.h> | |
27 | #include <linux/init.h> | |
c71099ac | 28 | #include <linux/list.h> |
5a0e3ad6 | 29 | #include <linux/slab.h> |
1da177e4 LT |
30 | |
31 | #ifdef CONFIG_PROC_FS | |
32 | #include <linux/proc_fs.h> | |
33 | #endif | |
34 | ||
35 | #include <net/ipv6.h> | |
36 | #include <net/ndisc.h> | |
37 | #include <net/addrconf.h> | |
38 | ||
39 | #include <net/ip6_fib.h> | |
40 | #include <net/ip6_route.h> | |
41 | ||
42 | #define RT6_DEBUG 2 | |
43 | ||
44 | #if RT6_DEBUG >= 3 | |
45 | #define RT6_TRACE(x...) printk(KERN_DEBUG x) | |
46 | #else | |
47 | #define RT6_TRACE(x...) do { ; } while (0) | |
48 | #endif | |
49 | ||
e18b890b | 50 | static struct kmem_cache * fib6_node_kmem __read_mostly; |
1da177e4 LT |
51 | |
52 | enum fib_walk_state_t | |
53 | { | |
54 | #ifdef CONFIG_IPV6_SUBTREES | |
55 | FWS_S, | |
56 | #endif | |
57 | FWS_L, | |
58 | FWS_R, | |
59 | FWS_C, | |
60 | FWS_U | |
61 | }; | |
62 | ||
63 | struct fib6_cleaner_t | |
64 | { | |
65 | struct fib6_walker_t w; | |
ec7d43c2 | 66 | struct net *net; |
1da177e4 LT |
67 | int (*func)(struct rt6_info *, void *arg); |
68 | void *arg; | |
69 | }; | |
70 | ||
90d41122 | 71 | static DEFINE_RWLOCK(fib6_walker_lock); |
1da177e4 LT |
72 | |
73 | #ifdef CONFIG_IPV6_SUBTREES | |
74 | #define FWS_INIT FWS_S | |
1da177e4 LT |
75 | #else |
76 | #define FWS_INIT FWS_L | |
1da177e4 LT |
77 | #endif |
78 | ||
ec7d43c2 BT |
79 | static void fib6_prune_clones(struct net *net, struct fib6_node *fn, |
80 | struct rt6_info *rt); | |
8ed67789 DL |
81 | static struct rt6_info *fib6_find_prefix(struct net *net, struct fib6_node *fn); |
82 | static struct fib6_node *fib6_repair_tree(struct net *net, struct fib6_node *fn); | |
90d41122 AB |
83 | static int fib6_walk(struct fib6_walker_t *w); |
84 | static int fib6_walk_continue(struct fib6_walker_t *w); | |
1da177e4 LT |
85 | |
86 | /* | |
87 | * A routing update causes an increase of the serial number on the | |
88 | * affected subtree. This allows for cached routes to be asynchronously | |
89 | * tested when modifications are made to the destination cache as a | |
90 | * result of redirects, path MTU changes, etc. | |
91 | */ | |
92 | ||
93 | static __u32 rt_sernum; | |
94 | ||
5b7c931d DL |
95 | static void fib6_gc_timer_cb(unsigned long arg); |
96 | ||
bbef49da AD |
97 | static LIST_HEAD(fib6_walkers); |
98 | #define FOR_WALKERS(w) list_for_each_entry(w, &fib6_walkers, lh) | |
1da177e4 | 99 | |
90d41122 AB |
100 | static inline void fib6_walker_link(struct fib6_walker_t *w) |
101 | { | |
102 | write_lock_bh(&fib6_walker_lock); | |
bbef49da | 103 | list_add(&w->lh, &fib6_walkers); |
90d41122 AB |
104 | write_unlock_bh(&fib6_walker_lock); |
105 | } | |
106 | ||
107 | static inline void fib6_walker_unlink(struct fib6_walker_t *w) | |
108 | { | |
109 | write_lock_bh(&fib6_walker_lock); | |
bbef49da | 110 | list_del(&w->lh); |
90d41122 AB |
111 | write_unlock_bh(&fib6_walker_lock); |
112 | } | |
1da177e4 LT |
113 | static __inline__ u32 fib6_new_sernum(void) |
114 | { | |
115 | u32 n = ++rt_sernum; | |
116 | if ((__s32)n <= 0) | |
117 | rt_sernum = n = 1; | |
118 | return n; | |
119 | } | |
120 | ||
121 | /* | |
122 | * Auxiliary address test functions for the radix tree. | |
123 | * | |
1ab1457c | 124 | * These assume a 32bit processor (although it will work on |
1da177e4 LT |
125 | * 64bit processors) |
126 | */ | |
127 | ||
128 | /* | |
129 | * test bit | |
130 | */ | |
02cdce53 YH |
131 | #if defined(__LITTLE_ENDIAN) |
132 | # define BITOP_BE32_SWIZZLE (0x1F & ~7) | |
133 | #else | |
134 | # define BITOP_BE32_SWIZZLE 0 | |
135 | #endif | |
1da177e4 | 136 | |
e69a4adc | 137 | static __inline__ __be32 addr_bit_set(void *token, int fn_bit) |
1da177e4 | 138 | { |
e69a4adc | 139 | __be32 *addr = token; |
02cdce53 YH |
140 | /* |
141 | * Here, | |
142 | * 1 << ((~fn_bit ^ BITOP_BE32_SWIZZLE) & 0x1f) | |
143 | * is optimized version of | |
144 | * htonl(1 << ((~fn_bit)&0x1F)) | |
145 | * See include/asm-generic/bitops/le.h. | |
146 | */ | |
0eae88f3 ED |
147 | return (__force __be32)(1 << ((~fn_bit ^ BITOP_BE32_SWIZZLE) & 0x1f)) & |
148 | addr[fn_bit >> 5]; | |
1da177e4 LT |
149 | } |
150 | ||
1da177e4 LT |
151 | static __inline__ struct fib6_node * node_alloc(void) |
152 | { | |
153 | struct fib6_node *fn; | |
154 | ||
c3762229 | 155 | fn = kmem_cache_zalloc(fib6_node_kmem, GFP_ATOMIC); |
1da177e4 LT |
156 | |
157 | return fn; | |
158 | } | |
159 | ||
160 | static __inline__ void node_free(struct fib6_node * fn) | |
161 | { | |
162 | kmem_cache_free(fib6_node_kmem, fn); | |
163 | } | |
164 | ||
165 | static __inline__ void rt6_release(struct rt6_info *rt) | |
166 | { | |
167 | if (atomic_dec_and_test(&rt->rt6i_ref)) | |
168 | dst_free(&rt->u.dst); | |
169 | } | |
170 | ||
58f09b78 | 171 | static void fib6_link_table(struct net *net, struct fib6_table *tb) |
1b43af54 PM |
172 | { |
173 | unsigned int h; | |
174 | ||
375216ad TG |
175 | /* |
176 | * Initialize table lock at a single place to give lockdep a key, | |
177 | * tables aren't visible prior to being linked to the list. | |
178 | */ | |
179 | rwlock_init(&tb->tb6_lock); | |
180 | ||
a33bc5c1 | 181 | h = tb->tb6_id & (FIB6_TABLE_HASHSZ - 1); |
1b43af54 PM |
182 | |
183 | /* | |
184 | * No protection necessary, this is the only list mutatation | |
185 | * operation, tables never disappear once they exist. | |
186 | */ | |
58f09b78 | 187 | hlist_add_head_rcu(&tb->tb6_hlist, &net->ipv6.fib_table_hash[h]); |
1b43af54 | 188 | } |
c71099ac | 189 | |
1b43af54 | 190 | #ifdef CONFIG_IPV6_MULTIPLE_TABLES |
e0b85590 | 191 | |
8ed67789 | 192 | static struct fib6_table *fib6_alloc_table(struct net *net, u32 id) |
c71099ac TG |
193 | { |
194 | struct fib6_table *table; | |
195 | ||
196 | table = kzalloc(sizeof(*table), GFP_ATOMIC); | |
197 | if (table != NULL) { | |
198 | table->tb6_id = id; | |
8ed67789 | 199 | table->tb6_root.leaf = net->ipv6.ip6_null_entry; |
c71099ac TG |
200 | table->tb6_root.fn_flags = RTN_ROOT | RTN_TL_ROOT | RTN_RTINFO; |
201 | } | |
202 | ||
203 | return table; | |
204 | } | |
205 | ||
58f09b78 | 206 | struct fib6_table *fib6_new_table(struct net *net, u32 id) |
c71099ac TG |
207 | { |
208 | struct fib6_table *tb; | |
209 | ||
210 | if (id == 0) | |
211 | id = RT6_TABLE_MAIN; | |
58f09b78 | 212 | tb = fib6_get_table(net, id); |
c71099ac TG |
213 | if (tb) |
214 | return tb; | |
215 | ||
8ed67789 | 216 | tb = fib6_alloc_table(net, id); |
c71099ac | 217 | if (tb != NULL) |
58f09b78 | 218 | fib6_link_table(net, tb); |
c71099ac TG |
219 | |
220 | return tb; | |
221 | } | |
222 | ||
58f09b78 | 223 | struct fib6_table *fib6_get_table(struct net *net, u32 id) |
c71099ac TG |
224 | { |
225 | struct fib6_table *tb; | |
58f09b78 | 226 | struct hlist_head *head; |
c71099ac TG |
227 | struct hlist_node *node; |
228 | unsigned int h; | |
229 | ||
230 | if (id == 0) | |
231 | id = RT6_TABLE_MAIN; | |
a33bc5c1 | 232 | h = id & (FIB6_TABLE_HASHSZ - 1); |
c71099ac | 233 | rcu_read_lock(); |
58f09b78 DL |
234 | head = &net->ipv6.fib_table_hash[h]; |
235 | hlist_for_each_entry_rcu(tb, node, head, tb6_hlist) { | |
c71099ac TG |
236 | if (tb->tb6_id == id) { |
237 | rcu_read_unlock(); | |
238 | return tb; | |
239 | } | |
240 | } | |
241 | rcu_read_unlock(); | |
242 | ||
243 | return NULL; | |
244 | } | |
245 | ||
2c8c1e72 | 246 | static void __net_init fib6_tables_init(struct net *net) |
c71099ac | 247 | { |
58f09b78 DL |
248 | fib6_link_table(net, net->ipv6.fib6_main_tbl); |
249 | fib6_link_table(net, net->ipv6.fib6_local_tbl); | |
c71099ac | 250 | } |
c71099ac TG |
251 | #else |
252 | ||
58f09b78 | 253 | struct fib6_table *fib6_new_table(struct net *net, u32 id) |
c71099ac | 254 | { |
58f09b78 | 255 | return fib6_get_table(net, id); |
c71099ac TG |
256 | } |
257 | ||
58f09b78 | 258 | struct fib6_table *fib6_get_table(struct net *net, u32 id) |
c71099ac | 259 | { |
58f09b78 | 260 | return net->ipv6.fib6_main_tbl; |
c71099ac TG |
261 | } |
262 | ||
58f09b78 DL |
263 | struct dst_entry *fib6_rule_lookup(struct net *net, struct flowi *fl, |
264 | int flags, pol_lookup_t lookup) | |
c71099ac | 265 | { |
8ed67789 | 266 | return (struct dst_entry *) lookup(net, net->ipv6.fib6_main_tbl, fl, flags); |
c71099ac TG |
267 | } |
268 | ||
2c8c1e72 | 269 | static void __net_init fib6_tables_init(struct net *net) |
c71099ac | 270 | { |
58f09b78 | 271 | fib6_link_table(net, net->ipv6.fib6_main_tbl); |
c71099ac TG |
272 | } |
273 | ||
274 | #endif | |
275 | ||
1b43af54 PM |
276 | static int fib6_dump_node(struct fib6_walker_t *w) |
277 | { | |
278 | int res; | |
279 | struct rt6_info *rt; | |
280 | ||
7cc48263 | 281 | for (rt = w->leaf; rt; rt = rt->u.dst.rt6_next) { |
1b43af54 PM |
282 | res = rt6_dump_route(rt, w->args); |
283 | if (res < 0) { | |
284 | /* Frame is full, suspend walking */ | |
285 | w->leaf = rt; | |
286 | return 1; | |
287 | } | |
547b792c | 288 | WARN_ON(res == 0); |
1b43af54 PM |
289 | } |
290 | w->leaf = NULL; | |
291 | return 0; | |
292 | } | |
293 | ||
294 | static void fib6_dump_end(struct netlink_callback *cb) | |
295 | { | |
296 | struct fib6_walker_t *w = (void*)cb->args[2]; | |
297 | ||
298 | if (w) { | |
7891cc81 HX |
299 | if (cb->args[4]) { |
300 | cb->args[4] = 0; | |
301 | fib6_walker_unlink(w); | |
302 | } | |
1b43af54 PM |
303 | cb->args[2] = 0; |
304 | kfree(w); | |
305 | } | |
306 | cb->done = (void*)cb->args[3]; | |
307 | cb->args[1] = 3; | |
308 | } | |
309 | ||
310 | static int fib6_dump_done(struct netlink_callback *cb) | |
311 | { | |
312 | fib6_dump_end(cb); | |
313 | return cb->done ? cb->done(cb) : 0; | |
314 | } | |
315 | ||
316 | static int fib6_dump_table(struct fib6_table *table, struct sk_buff *skb, | |
317 | struct netlink_callback *cb) | |
318 | { | |
319 | struct fib6_walker_t *w; | |
320 | int res; | |
321 | ||
322 | w = (void *)cb->args[2]; | |
323 | w->root = &table->tb6_root; | |
324 | ||
325 | if (cb->args[4] == 0) { | |
2bec5a36 PM |
326 | w->count = 0; |
327 | w->skip = 0; | |
328 | ||
1b43af54 PM |
329 | read_lock_bh(&table->tb6_lock); |
330 | res = fib6_walk(w); | |
331 | read_unlock_bh(&table->tb6_lock); | |
2bec5a36 | 332 | if (res > 0) { |
1b43af54 | 333 | cb->args[4] = 1; |
2bec5a36 PM |
334 | cb->args[5] = w->root->fn_sernum; |
335 | } | |
1b43af54 | 336 | } else { |
2bec5a36 PM |
337 | if (cb->args[5] != w->root->fn_sernum) { |
338 | /* Begin at the root if the tree changed */ | |
339 | cb->args[5] = w->root->fn_sernum; | |
340 | w->state = FWS_INIT; | |
341 | w->node = w->root; | |
342 | w->skip = w->count; | |
343 | } else | |
344 | w->skip = 0; | |
345 | ||
1b43af54 PM |
346 | read_lock_bh(&table->tb6_lock); |
347 | res = fib6_walk_continue(w); | |
348 | read_unlock_bh(&table->tb6_lock); | |
7891cc81 HX |
349 | if (res <= 0) { |
350 | fib6_walker_unlink(w); | |
351 | cb->args[4] = 0; | |
1b43af54 | 352 | } |
1b43af54 | 353 | } |
7891cc81 | 354 | |
1b43af54 PM |
355 | return res; |
356 | } | |
357 | ||
c127ea2c | 358 | static int inet6_dump_fib(struct sk_buff *skb, struct netlink_callback *cb) |
1b43af54 | 359 | { |
3b1e0a65 | 360 | struct net *net = sock_net(skb->sk); |
1b43af54 PM |
361 | unsigned int h, s_h; |
362 | unsigned int e = 0, s_e; | |
363 | struct rt6_rtnl_dump_arg arg; | |
364 | struct fib6_walker_t *w; | |
365 | struct fib6_table *tb; | |
366 | struct hlist_node *node; | |
58f09b78 | 367 | struct hlist_head *head; |
1b43af54 PM |
368 | int res = 0; |
369 | ||
370 | s_h = cb->args[0]; | |
371 | s_e = cb->args[1]; | |
372 | ||
373 | w = (void *)cb->args[2]; | |
374 | if (w == NULL) { | |
375 | /* New dump: | |
376 | * | |
377 | * 1. hook callback destructor. | |
378 | */ | |
379 | cb->args[3] = (long)cb->done; | |
380 | cb->done = fib6_dump_done; | |
381 | ||
382 | /* | |
383 | * 2. allocate and initialize walker. | |
384 | */ | |
385 | w = kzalloc(sizeof(*w), GFP_ATOMIC); | |
386 | if (w == NULL) | |
387 | return -ENOMEM; | |
388 | w->func = fib6_dump_node; | |
389 | cb->args[2] = (long)w; | |
390 | } | |
391 | ||
392 | arg.skb = skb; | |
393 | arg.cb = cb; | |
191cd582 | 394 | arg.net = net; |
1b43af54 PM |
395 | w->args = &arg; |
396 | ||
a33bc5c1 | 397 | for (h = s_h; h < FIB6_TABLE_HASHSZ; h++, s_e = 0) { |
1b43af54 | 398 | e = 0; |
58f09b78 DL |
399 | head = &net->ipv6.fib_table_hash[h]; |
400 | hlist_for_each_entry(tb, node, head, tb6_hlist) { | |
1b43af54 PM |
401 | if (e < s_e) |
402 | goto next; | |
403 | res = fib6_dump_table(tb, skb, cb); | |
404 | if (res != 0) | |
405 | goto out; | |
406 | next: | |
407 | e++; | |
408 | } | |
409 | } | |
410 | out: | |
411 | cb->args[1] = e; | |
412 | cb->args[0] = h; | |
413 | ||
414 | res = res < 0 ? res : skb->len; | |
415 | if (res <= 0) | |
416 | fib6_dump_end(cb); | |
417 | return res; | |
418 | } | |
1da177e4 LT |
419 | |
420 | /* | |
421 | * Routing Table | |
422 | * | |
423 | * return the appropriate node for a routing tree "add" operation | |
424 | * by either creating and inserting or by returning an existing | |
425 | * node. | |
426 | */ | |
427 | ||
428 | static struct fib6_node * fib6_add_1(struct fib6_node *root, void *addr, | |
429 | int addrlen, int plen, | |
430 | int offset) | |
431 | { | |
432 | struct fib6_node *fn, *in, *ln; | |
433 | struct fib6_node *pn = NULL; | |
434 | struct rt6key *key; | |
435 | int bit; | |
1ab1457c | 436 | __be32 dir = 0; |
1da177e4 LT |
437 | __u32 sernum = fib6_new_sernum(); |
438 | ||
439 | RT6_TRACE("fib6_add_1\n"); | |
440 | ||
441 | /* insert node in tree */ | |
442 | ||
443 | fn = root; | |
444 | ||
445 | do { | |
446 | key = (struct rt6key *)((u8 *)fn->leaf + offset); | |
447 | ||
448 | /* | |
449 | * Prefix match | |
450 | */ | |
451 | if (plen < fn->fn_bit || | |
452 | !ipv6_prefix_equal(&key->addr, addr, fn->fn_bit)) | |
453 | goto insert_above; | |
1ab1457c | 454 | |
1da177e4 LT |
455 | /* |
456 | * Exact match ? | |
457 | */ | |
1ab1457c | 458 | |
1da177e4 LT |
459 | if (plen == fn->fn_bit) { |
460 | /* clean up an intermediate node */ | |
461 | if ((fn->fn_flags & RTN_RTINFO) == 0) { | |
462 | rt6_release(fn->leaf); | |
463 | fn->leaf = NULL; | |
464 | } | |
1ab1457c | 465 | |
1da177e4 | 466 | fn->fn_sernum = sernum; |
1ab1457c | 467 | |
1da177e4 LT |
468 | return fn; |
469 | } | |
470 | ||
471 | /* | |
472 | * We have more bits to go | |
473 | */ | |
1ab1457c | 474 | |
1da177e4 LT |
475 | /* Try to walk down on tree. */ |
476 | fn->fn_sernum = sernum; | |
477 | dir = addr_bit_set(addr, fn->fn_bit); | |
478 | pn = fn; | |
479 | fn = dir ? fn->right: fn->left; | |
480 | } while (fn); | |
481 | ||
482 | /* | |
483 | * We walked to the bottom of tree. | |
484 | * Create new leaf node without children. | |
485 | */ | |
486 | ||
487 | ln = node_alloc(); | |
488 | ||
489 | if (ln == NULL) | |
490 | return NULL; | |
491 | ln->fn_bit = plen; | |
1ab1457c | 492 | |
1da177e4 LT |
493 | ln->parent = pn; |
494 | ln->fn_sernum = sernum; | |
495 | ||
496 | if (dir) | |
497 | pn->right = ln; | |
498 | else | |
499 | pn->left = ln; | |
500 | ||
501 | return ln; | |
502 | ||
503 | ||
504 | insert_above: | |
505 | /* | |
1ab1457c | 506 | * split since we don't have a common prefix anymore or |
1da177e4 LT |
507 | * we have a less significant route. |
508 | * we've to insert an intermediate node on the list | |
509 | * this new node will point to the one we need to create | |
510 | * and the current | |
511 | */ | |
512 | ||
513 | pn = fn->parent; | |
514 | ||
515 | /* find 1st bit in difference between the 2 addrs. | |
516 | ||
971f359d | 517 | See comment in __ipv6_addr_diff: bit may be an invalid value, |
1da177e4 LT |
518 | but if it is >= plen, the value is ignored in any case. |
519 | */ | |
1ab1457c | 520 | |
971f359d | 521 | bit = __ipv6_addr_diff(addr, &key->addr, addrlen); |
1da177e4 | 522 | |
1ab1457c YH |
523 | /* |
524 | * (intermediate)[in] | |
1da177e4 LT |
525 | * / \ |
526 | * (new leaf node)[ln] (old node)[fn] | |
527 | */ | |
528 | if (plen > bit) { | |
529 | in = node_alloc(); | |
530 | ln = node_alloc(); | |
1ab1457c | 531 | |
1da177e4 LT |
532 | if (in == NULL || ln == NULL) { |
533 | if (in) | |
534 | node_free(in); | |
535 | if (ln) | |
536 | node_free(ln); | |
537 | return NULL; | |
538 | } | |
539 | ||
1ab1457c YH |
540 | /* |
541 | * new intermediate node. | |
1da177e4 LT |
542 | * RTN_RTINFO will |
543 | * be off since that an address that chooses one of | |
544 | * the branches would not match less specific routes | |
545 | * in the other branch | |
546 | */ | |
547 | ||
548 | in->fn_bit = bit; | |
549 | ||
550 | in->parent = pn; | |
551 | in->leaf = fn->leaf; | |
552 | atomic_inc(&in->leaf->rt6i_ref); | |
553 | ||
554 | in->fn_sernum = sernum; | |
555 | ||
556 | /* update parent pointer */ | |
557 | if (dir) | |
558 | pn->right = in; | |
559 | else | |
560 | pn->left = in; | |
561 | ||
562 | ln->fn_bit = plen; | |
563 | ||
564 | ln->parent = in; | |
565 | fn->parent = in; | |
566 | ||
567 | ln->fn_sernum = sernum; | |
568 | ||
569 | if (addr_bit_set(addr, bit)) { | |
570 | in->right = ln; | |
571 | in->left = fn; | |
572 | } else { | |
573 | in->left = ln; | |
574 | in->right = fn; | |
575 | } | |
576 | } else { /* plen <= bit */ | |
577 | ||
1ab1457c | 578 | /* |
1da177e4 LT |
579 | * (new leaf node)[ln] |
580 | * / \ | |
581 | * (old node)[fn] NULL | |
582 | */ | |
583 | ||
584 | ln = node_alloc(); | |
585 | ||
586 | if (ln == NULL) | |
587 | return NULL; | |
588 | ||
589 | ln->fn_bit = plen; | |
590 | ||
591 | ln->parent = pn; | |
592 | ||
593 | ln->fn_sernum = sernum; | |
1ab1457c | 594 | |
1da177e4 LT |
595 | if (dir) |
596 | pn->right = ln; | |
597 | else | |
598 | pn->left = ln; | |
599 | ||
600 | if (addr_bit_set(&key->addr, plen)) | |
601 | ln->right = fn; | |
602 | else | |
603 | ln->left = fn; | |
604 | ||
605 | fn->parent = ln; | |
606 | } | |
607 | return ln; | |
608 | } | |
609 | ||
610 | /* | |
611 | * Insert routing information in a node. | |
612 | */ | |
613 | ||
614 | static int fib6_add_rt2node(struct fib6_node *fn, struct rt6_info *rt, | |
86872cb5 | 615 | struct nl_info *info) |
1da177e4 LT |
616 | { |
617 | struct rt6_info *iter = NULL; | |
618 | struct rt6_info **ins; | |
619 | ||
620 | ins = &fn->leaf; | |
621 | ||
7cc48263 | 622 | for (iter = fn->leaf; iter; iter=iter->u.dst.rt6_next) { |
1da177e4 LT |
623 | /* |
624 | * Search for duplicates | |
625 | */ | |
626 | ||
627 | if (iter->rt6i_metric == rt->rt6i_metric) { | |
628 | /* | |
629 | * Same priority level | |
630 | */ | |
631 | ||
632 | if (iter->rt6i_dev == rt->rt6i_dev && | |
633 | iter->rt6i_idev == rt->rt6i_idev && | |
634 | ipv6_addr_equal(&iter->rt6i_gateway, | |
635 | &rt->rt6i_gateway)) { | |
636 | if (!(iter->rt6i_flags&RTF_EXPIRES)) | |
637 | return -EEXIST; | |
638 | iter->rt6i_expires = rt->rt6i_expires; | |
639 | if (!(rt->rt6i_flags&RTF_EXPIRES)) { | |
640 | iter->rt6i_flags &= ~RTF_EXPIRES; | |
641 | iter->rt6i_expires = 0; | |
642 | } | |
643 | return -EEXIST; | |
644 | } | |
645 | } | |
646 | ||
647 | if (iter->rt6i_metric > rt->rt6i_metric) | |
648 | break; | |
649 | ||
7cc48263 | 650 | ins = &iter->u.dst.rt6_next; |
1da177e4 LT |
651 | } |
652 | ||
f11e6659 DM |
653 | /* Reset round-robin state, if necessary */ |
654 | if (ins == &fn->leaf) | |
655 | fn->rr_ptr = NULL; | |
656 | ||
1da177e4 LT |
657 | /* |
658 | * insert node | |
659 | */ | |
660 | ||
7cc48263 | 661 | rt->u.dst.rt6_next = iter; |
1da177e4 LT |
662 | *ins = rt; |
663 | rt->rt6i_node = fn; | |
664 | atomic_inc(&rt->rt6i_ref); | |
86872cb5 | 665 | inet6_rt_notify(RTM_NEWROUTE, rt, info); |
c572872f | 666 | info->nl_net->ipv6.rt6_stats->fib_rt_entries++; |
1da177e4 LT |
667 | |
668 | if ((fn->fn_flags & RTN_RTINFO) == 0) { | |
c572872f | 669 | info->nl_net->ipv6.rt6_stats->fib_route_nodes++; |
1da177e4 LT |
670 | fn->fn_flags |= RTN_RTINFO; |
671 | } | |
672 | ||
673 | return 0; | |
674 | } | |
675 | ||
63152fc0 | 676 | static __inline__ void fib6_start_gc(struct net *net, struct rt6_info *rt) |
1da177e4 | 677 | { |
417f28bb | 678 | if (!timer_pending(&net->ipv6.ip6_fib_timer) && |
1da177e4 | 679 | (rt->rt6i_flags & (RTF_EXPIRES|RTF_CACHE))) |
417f28bb | 680 | mod_timer(&net->ipv6.ip6_fib_timer, |
847499ce | 681 | jiffies + net->ipv6.sysctl.ip6_rt_gc_interval); |
1da177e4 LT |
682 | } |
683 | ||
63152fc0 | 684 | void fib6_force_start_gc(struct net *net) |
1da177e4 | 685 | { |
417f28bb SH |
686 | if (!timer_pending(&net->ipv6.ip6_fib_timer)) |
687 | mod_timer(&net->ipv6.ip6_fib_timer, | |
847499ce | 688 | jiffies + net->ipv6.sysctl.ip6_rt_gc_interval); |
1da177e4 LT |
689 | } |
690 | ||
691 | /* | |
692 | * Add routing information to the routing tree. | |
693 | * <destination addr>/<source addr> | |
694 | * with source addr info in sub-trees | |
695 | */ | |
696 | ||
86872cb5 | 697 | int fib6_add(struct fib6_node *root, struct rt6_info *rt, struct nl_info *info) |
1da177e4 | 698 | { |
66729e18 | 699 | struct fib6_node *fn, *pn = NULL; |
1da177e4 LT |
700 | int err = -ENOMEM; |
701 | ||
702 | fn = fib6_add_1(root, &rt->rt6i_dst.addr, sizeof(struct in6_addr), | |
703 | rt->rt6i_dst.plen, offsetof(struct rt6_info, rt6i_dst)); | |
704 | ||
705 | if (fn == NULL) | |
706 | goto out; | |
707 | ||
66729e18 YH |
708 | pn = fn; |
709 | ||
1da177e4 LT |
710 | #ifdef CONFIG_IPV6_SUBTREES |
711 | if (rt->rt6i_src.plen) { | |
712 | struct fib6_node *sn; | |
713 | ||
714 | if (fn->subtree == NULL) { | |
715 | struct fib6_node *sfn; | |
716 | ||
717 | /* | |
718 | * Create subtree. | |
719 | * | |
720 | * fn[main tree] | |
721 | * | | |
722 | * sfn[subtree root] | |
723 | * \ | |
724 | * sn[new leaf node] | |
725 | */ | |
726 | ||
727 | /* Create subtree root node */ | |
728 | sfn = node_alloc(); | |
729 | if (sfn == NULL) | |
730 | goto st_failure; | |
731 | ||
8ed67789 DL |
732 | sfn->leaf = info->nl_net->ipv6.ip6_null_entry; |
733 | atomic_inc(&info->nl_net->ipv6.ip6_null_entry->rt6i_ref); | |
1da177e4 LT |
734 | sfn->fn_flags = RTN_ROOT; |
735 | sfn->fn_sernum = fib6_new_sernum(); | |
736 | ||
737 | /* Now add the first leaf node to new subtree */ | |
738 | ||
739 | sn = fib6_add_1(sfn, &rt->rt6i_src.addr, | |
740 | sizeof(struct in6_addr), rt->rt6i_src.plen, | |
741 | offsetof(struct rt6_info, rt6i_src)); | |
742 | ||
743 | if (sn == NULL) { | |
744 | /* If it is failed, discard just allocated | |
745 | root, and then (in st_failure) stale node | |
746 | in main tree. | |
747 | */ | |
748 | node_free(sfn); | |
749 | goto st_failure; | |
750 | } | |
751 | ||
752 | /* Now link new subtree to main tree */ | |
753 | sfn->parent = fn; | |
754 | fn->subtree = sfn; | |
1da177e4 LT |
755 | } else { |
756 | sn = fib6_add_1(fn->subtree, &rt->rt6i_src.addr, | |
757 | sizeof(struct in6_addr), rt->rt6i_src.plen, | |
758 | offsetof(struct rt6_info, rt6i_src)); | |
759 | ||
760 | if (sn == NULL) | |
761 | goto st_failure; | |
762 | } | |
763 | ||
66729e18 YH |
764 | if (fn->leaf == NULL) { |
765 | fn->leaf = rt; | |
766 | atomic_inc(&rt->rt6i_ref); | |
767 | } | |
1da177e4 LT |
768 | fn = sn; |
769 | } | |
770 | #endif | |
771 | ||
86872cb5 | 772 | err = fib6_add_rt2node(fn, rt, info); |
1da177e4 LT |
773 | |
774 | if (err == 0) { | |
63152fc0 | 775 | fib6_start_gc(info->nl_net, rt); |
1da177e4 | 776 | if (!(rt->rt6i_flags&RTF_CACHE)) |
ec7d43c2 | 777 | fib6_prune_clones(info->nl_net, pn, rt); |
1da177e4 LT |
778 | } |
779 | ||
780 | out: | |
66729e18 YH |
781 | if (err) { |
782 | #ifdef CONFIG_IPV6_SUBTREES | |
783 | /* | |
784 | * If fib6_add_1 has cleared the old leaf pointer in the | |
785 | * super-tree leaf node we have to find a new one for it. | |
786 | */ | |
3c051235 DM |
787 | if (pn != fn && pn->leaf == rt) { |
788 | pn->leaf = NULL; | |
789 | atomic_dec(&rt->rt6i_ref); | |
790 | } | |
66729e18 | 791 | if (pn != fn && !pn->leaf && !(pn->fn_flags & RTN_RTINFO)) { |
8ed67789 | 792 | pn->leaf = fib6_find_prefix(info->nl_net, pn); |
66729e18 YH |
793 | #if RT6_DEBUG >= 2 |
794 | if (!pn->leaf) { | |
547b792c | 795 | WARN_ON(pn->leaf == NULL); |
8ed67789 | 796 | pn->leaf = info->nl_net->ipv6.ip6_null_entry; |
66729e18 YH |
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))) | |
8ed67789 | 812 | fib6_repair_tree(info->nl_net, fn); |
1da177e4 LT |
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) { | |
547b792c | 959 | WARN_ON(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 | ||
8ed67789 | 978 | static struct rt6_info *fib6_find_prefix(struct net *net, struct fib6_node *fn) |
1da177e4 LT |
979 | { |
980 | if (fn->fn_flags&RTN_ROOT) | |
8ed67789 | 981 | return net->ipv6.ip6_null_entry; |
1da177e4 LT |
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 | ||
8ed67789 DL |
1000 | static struct fib6_node *fib6_repair_tree(struct net *net, |
1001 | struct fib6_node *fn) | |
1da177e4 LT |
1002 | { |
1003 | int children; | |
1004 | int nstate; | |
1005 | struct fib6_node *child, *pn; | |
1006 | struct fib6_walker_t *w; | |
1007 | int iter = 0; | |
1008 | ||
1009 | for (;;) { | |
1010 | RT6_TRACE("fixing tree: plen=%d iter=%d\n", fn->fn_bit, iter); | |
1011 | iter++; | |
1012 | ||
547b792c IJ |
1013 | WARN_ON(fn->fn_flags & RTN_RTINFO); |
1014 | WARN_ON(fn->fn_flags & RTN_TL_ROOT); | |
1015 | WARN_ON(fn->leaf != NULL); | |
1da177e4 LT |
1016 | |
1017 | children = 0; | |
1018 | child = NULL; | |
1019 | if (fn->right) child = fn->right, children |= 1; | |
1020 | if (fn->left) child = fn->left, children |= 2; | |
1021 | ||
7fc33165 | 1022 | if (children == 3 || FIB6_SUBTREE(fn) |
1da177e4 LT |
1023 | #ifdef CONFIG_IPV6_SUBTREES |
1024 | /* Subtree root (i.e. fn) may have one child */ | |
1025 | || (children && fn->fn_flags&RTN_ROOT) | |
1026 | #endif | |
1027 | ) { | |
8ed67789 | 1028 | fn->leaf = fib6_find_prefix(net, fn); |
1da177e4 LT |
1029 | #if RT6_DEBUG >= 2 |
1030 | if (fn->leaf==NULL) { | |
547b792c | 1031 | WARN_ON(!fn->leaf); |
8ed67789 | 1032 | fn->leaf = net->ipv6.ip6_null_entry; |
1da177e4 LT |
1033 | } |
1034 | #endif | |
1035 | atomic_inc(&fn->leaf->rt6i_ref); | |
1036 | return fn->parent; | |
1037 | } | |
1038 | ||
1039 | pn = fn->parent; | |
1040 | #ifdef CONFIG_IPV6_SUBTREES | |
7fc33165 | 1041 | if (FIB6_SUBTREE(pn) == fn) { |
547b792c | 1042 | WARN_ON(!(fn->fn_flags & RTN_ROOT)); |
7fc33165 | 1043 | FIB6_SUBTREE(pn) = NULL; |
1da177e4 LT |
1044 | nstate = FWS_L; |
1045 | } else { | |
547b792c | 1046 | WARN_ON(fn->fn_flags & RTN_ROOT); |
1da177e4 LT |
1047 | #endif |
1048 | if (pn->right == fn) pn->right = child; | |
1049 | else if (pn->left == fn) pn->left = child; | |
1050 | #if RT6_DEBUG >= 2 | |
547b792c IJ |
1051 | else |
1052 | WARN_ON(1); | |
1da177e4 LT |
1053 | #endif |
1054 | if (child) | |
1055 | child->parent = pn; | |
1056 | nstate = FWS_R; | |
1057 | #ifdef CONFIG_IPV6_SUBTREES | |
1058 | } | |
1059 | #endif | |
1060 | ||
1061 | read_lock(&fib6_walker_lock); | |
1062 | FOR_WALKERS(w) { | |
1063 | if (child == NULL) { | |
1064 | if (w->root == fn) { | |
1065 | w->root = w->node = NULL; | |
1066 | RT6_TRACE("W %p adjusted by delroot 1\n", w); | |
1067 | } else if (w->node == fn) { | |
1068 | RT6_TRACE("W %p adjusted by delnode 1, s=%d/%d\n", w, w->state, nstate); | |
1069 | w->node = pn; | |
1070 | w->state = nstate; | |
1071 | } | |
1072 | } else { | |
1073 | if (w->root == fn) { | |
1074 | w->root = child; | |
1075 | RT6_TRACE("W %p adjusted by delroot 2\n", w); | |
1076 | } | |
1077 | if (w->node == fn) { | |
1078 | w->node = child; | |
1079 | if (children&2) { | |
1080 | RT6_TRACE("W %p adjusted by delnode 2, s=%d\n", w, w->state); | |
1081 | w->state = w->state>=FWS_R ? FWS_U : FWS_INIT; | |
1082 | } else { | |
1083 | RT6_TRACE("W %p adjusted by delnode 2, s=%d\n", w, w->state); | |
1084 | w->state = w->state>=FWS_C ? FWS_U : FWS_INIT; | |
1085 | } | |
1086 | } | |
1087 | } | |
1088 | } | |
1089 | read_unlock(&fib6_walker_lock); | |
1090 | ||
1091 | node_free(fn); | |
7fc33165 | 1092 | if (pn->fn_flags&RTN_RTINFO || FIB6_SUBTREE(pn)) |
1da177e4 LT |
1093 | return pn; |
1094 | ||
1095 | rt6_release(pn->leaf); | |
1096 | pn->leaf = NULL; | |
1097 | fn = pn; | |
1098 | } | |
1099 | } | |
1100 | ||
1101 | static void fib6_del_route(struct fib6_node *fn, struct rt6_info **rtp, | |
86872cb5 | 1102 | struct nl_info *info) |
1da177e4 LT |
1103 | { |
1104 | struct fib6_walker_t *w; | |
1105 | struct rt6_info *rt = *rtp; | |
c572872f | 1106 | struct net *net = info->nl_net; |
1da177e4 LT |
1107 | |
1108 | RT6_TRACE("fib6_del_route\n"); | |
1109 | ||
1110 | /* Unlink it */ | |
7cc48263 | 1111 | *rtp = rt->u.dst.rt6_next; |
1da177e4 | 1112 | rt->rt6i_node = NULL; |
c572872f BT |
1113 | net->ipv6.rt6_stats->fib_rt_entries--; |
1114 | net->ipv6.rt6_stats->fib_discarded_routes++; | |
1da177e4 | 1115 | |
f11e6659 DM |
1116 | /* Reset round-robin state, if necessary */ |
1117 | if (fn->rr_ptr == rt) | |
1118 | fn->rr_ptr = NULL; | |
1119 | ||
1da177e4 LT |
1120 | /* Adjust walkers */ |
1121 | read_lock(&fib6_walker_lock); | |
1122 | FOR_WALKERS(w) { | |
1123 | if (w->state == FWS_C && w->leaf == rt) { | |
1124 | RT6_TRACE("walker %p adjusted by delroute\n", w); | |
7cc48263 | 1125 | w->leaf = rt->u.dst.rt6_next; |
1da177e4 LT |
1126 | if (w->leaf == NULL) |
1127 | w->state = FWS_U; | |
1128 | } | |
1129 | } | |
1130 | read_unlock(&fib6_walker_lock); | |
1131 | ||
7cc48263 | 1132 | rt->u.dst.rt6_next = NULL; |
1da177e4 | 1133 | |
1da177e4 LT |
1134 | /* If it was last route, expunge its radix tree node */ |
1135 | if (fn->leaf == NULL) { | |
1136 | fn->fn_flags &= ~RTN_RTINFO; | |
c572872f | 1137 | net->ipv6.rt6_stats->fib_route_nodes--; |
8ed67789 | 1138 | fn = fib6_repair_tree(net, fn); |
1da177e4 LT |
1139 | } |
1140 | ||
1141 | if (atomic_read(&rt->rt6i_ref) != 1) { | |
1142 | /* This route is used as dummy address holder in some split | |
1143 | * nodes. It is not leaked, but it still holds other resources, | |
1144 | * which must be released in time. So, scan ascendant nodes | |
1145 | * and replace dummy references to this route with references | |
1146 | * to still alive ones. | |
1147 | */ | |
1148 | while (fn) { | |
1149 | if (!(fn->fn_flags&RTN_RTINFO) && fn->leaf == rt) { | |
8ed67789 | 1150 | fn->leaf = fib6_find_prefix(net, fn); |
1da177e4 LT |
1151 | atomic_inc(&fn->leaf->rt6i_ref); |
1152 | rt6_release(rt); | |
1153 | } | |
1154 | fn = fn->parent; | |
1155 | } | |
1156 | /* No more references are possible at this point. */ | |
2df96af0 | 1157 | BUG_ON(atomic_read(&rt->rt6i_ref) != 1); |
1da177e4 LT |
1158 | } |
1159 | ||
86872cb5 | 1160 | inet6_rt_notify(RTM_DELROUTE, rt, info); |
1da177e4 LT |
1161 | rt6_release(rt); |
1162 | } | |
1163 | ||
86872cb5 | 1164 | int fib6_del(struct rt6_info *rt, struct nl_info *info) |
1da177e4 | 1165 | { |
8ed67789 | 1166 | struct net *net = info->nl_net; |
1da177e4 LT |
1167 | struct fib6_node *fn = rt->rt6i_node; |
1168 | struct rt6_info **rtp; | |
1169 | ||
1170 | #if RT6_DEBUG >= 2 | |
1171 | if (rt->u.dst.obsolete>0) { | |
547b792c | 1172 | WARN_ON(fn != NULL); |
1da177e4 LT |
1173 | return -ENOENT; |
1174 | } | |
1175 | #endif | |
8ed67789 | 1176 | if (fn == NULL || rt == net->ipv6.ip6_null_entry) |
1da177e4 LT |
1177 | return -ENOENT; |
1178 | ||
547b792c | 1179 | WARN_ON(!(fn->fn_flags & RTN_RTINFO)); |
1da177e4 | 1180 | |
150730d5 YH |
1181 | if (!(rt->rt6i_flags&RTF_CACHE)) { |
1182 | struct fib6_node *pn = fn; | |
1183 | #ifdef CONFIG_IPV6_SUBTREES | |
1184 | /* clones of this route might be in another subtree */ | |
1185 | if (rt->rt6i_src.plen) { | |
1186 | while (!(pn->fn_flags&RTN_ROOT)) | |
1187 | pn = pn->parent; | |
1188 | pn = pn->parent; | |
1189 | } | |
1190 | #endif | |
ec7d43c2 | 1191 | fib6_prune_clones(info->nl_net, pn, rt); |
150730d5 | 1192 | } |
1da177e4 LT |
1193 | |
1194 | /* | |
1195 | * Walk the leaf entries looking for ourself | |
1196 | */ | |
1197 | ||
7cc48263 | 1198 | for (rtp = &fn->leaf; *rtp; rtp = &(*rtp)->u.dst.rt6_next) { |
1da177e4 | 1199 | if (*rtp == rt) { |
86872cb5 | 1200 | fib6_del_route(fn, rtp, info); |
1da177e4 LT |
1201 | return 0; |
1202 | } | |
1203 | } | |
1204 | return -ENOENT; | |
1205 | } | |
1206 | ||
1207 | /* | |
1208 | * Tree traversal function. | |
1209 | * | |
1210 | * Certainly, it is not interrupt safe. | |
1211 | * However, it is internally reenterable wrt itself and fib6_add/fib6_del. | |
1212 | * It means, that we can modify tree during walking | |
1213 | * and use this function for garbage collection, clone pruning, | |
1ab1457c | 1214 | * cleaning tree when a device goes down etc. etc. |
1da177e4 LT |
1215 | * |
1216 | * It guarantees that every node will be traversed, | |
1217 | * and that it will be traversed only once. | |
1218 | * | |
1219 | * Callback function w->func may return: | |
1220 | * 0 -> continue walking. | |
1221 | * positive value -> walking is suspended (used by tree dumps, | |
1222 | * and probably by gc, if it will be split to several slices) | |
1223 | * negative value -> terminate walking. | |
1224 | * | |
1225 | * The function itself returns: | |
1226 | * 0 -> walk is complete. | |
1227 | * >0 -> walk is incomplete (i.e. suspended) | |
1228 | * <0 -> walk is terminated by an error. | |
1229 | */ | |
1230 | ||
90d41122 | 1231 | static int fib6_walk_continue(struct fib6_walker_t *w) |
1da177e4 LT |
1232 | { |
1233 | struct fib6_node *fn, *pn; | |
1234 | ||
1235 | for (;;) { | |
1236 | fn = w->node; | |
1237 | if (fn == NULL) | |
1238 | return 0; | |
1239 | ||
1240 | if (w->prune && fn != w->root && | |
1241 | fn->fn_flags&RTN_RTINFO && w->state < FWS_C) { | |
1242 | w->state = FWS_C; | |
1243 | w->leaf = fn->leaf; | |
1244 | } | |
1245 | switch (w->state) { | |
1246 | #ifdef CONFIG_IPV6_SUBTREES | |
1247 | case FWS_S: | |
7fc33165 YH |
1248 | if (FIB6_SUBTREE(fn)) { |
1249 | w->node = FIB6_SUBTREE(fn); | |
1da177e4 LT |
1250 | continue; |
1251 | } | |
1252 | w->state = FWS_L; | |
1ab1457c | 1253 | #endif |
1da177e4 LT |
1254 | case FWS_L: |
1255 | if (fn->left) { | |
1256 | w->node = fn->left; | |
1257 | w->state = FWS_INIT; | |
1258 | continue; | |
1259 | } | |
1260 | w->state = FWS_R; | |
1261 | case FWS_R: | |
1262 | if (fn->right) { | |
1263 | w->node = fn->right; | |
1264 | w->state = FWS_INIT; | |
1265 | continue; | |
1266 | } | |
1267 | w->state = FWS_C; | |
1268 | w->leaf = fn->leaf; | |
1269 | case FWS_C: | |
1270 | if (w->leaf && fn->fn_flags&RTN_RTINFO) { | |
2bec5a36 PM |
1271 | int err; |
1272 | ||
1273 | if (w->count < w->skip) { | |
1274 | w->count++; | |
1275 | continue; | |
1276 | } | |
1277 | ||
1278 | err = w->func(w); | |
1da177e4 LT |
1279 | if (err) |
1280 | return err; | |
2bec5a36 PM |
1281 | |
1282 | w->count++; | |
1da177e4 LT |
1283 | continue; |
1284 | } | |
1285 | w->state = FWS_U; | |
1286 | case FWS_U: | |
1287 | if (fn == w->root) | |
1288 | return 0; | |
1289 | pn = fn->parent; | |
1290 | w->node = pn; | |
1291 | #ifdef CONFIG_IPV6_SUBTREES | |
7fc33165 | 1292 | if (FIB6_SUBTREE(pn) == fn) { |
547b792c | 1293 | WARN_ON(!(fn->fn_flags & RTN_ROOT)); |
1da177e4 LT |
1294 | w->state = FWS_L; |
1295 | continue; | |
1296 | } | |
1297 | #endif | |
1298 | if (pn->left == fn) { | |
1299 | w->state = FWS_R; | |
1300 | continue; | |
1301 | } | |
1302 | if (pn->right == fn) { | |
1303 | w->state = FWS_C; | |
1304 | w->leaf = w->node->leaf; | |
1305 | continue; | |
1306 | } | |
1307 | #if RT6_DEBUG >= 2 | |
547b792c | 1308 | WARN_ON(1); |
1da177e4 LT |
1309 | #endif |
1310 | } | |
1311 | } | |
1312 | } | |
1313 | ||
90d41122 | 1314 | static int fib6_walk(struct fib6_walker_t *w) |
1da177e4 LT |
1315 | { |
1316 | int res; | |
1317 | ||
1318 | w->state = FWS_INIT; | |
1319 | w->node = w->root; | |
1320 | ||
1321 | fib6_walker_link(w); | |
1322 | res = fib6_walk_continue(w); | |
1323 | if (res <= 0) | |
1324 | fib6_walker_unlink(w); | |
1325 | return res; | |
1326 | } | |
1327 | ||
1328 | static int fib6_clean_node(struct fib6_walker_t *w) | |
1329 | { | |
1330 | int res; | |
1331 | struct rt6_info *rt; | |
0a8891a0 | 1332 | struct fib6_cleaner_t *c = container_of(w, struct fib6_cleaner_t, w); |
ec7d43c2 BT |
1333 | struct nl_info info = { |
1334 | .nl_net = c->net, | |
1335 | }; | |
1da177e4 | 1336 | |
7cc48263 | 1337 | for (rt = w->leaf; rt; rt = rt->u.dst.rt6_next) { |
1da177e4 LT |
1338 | res = c->func(rt, c->arg); |
1339 | if (res < 0) { | |
1340 | w->leaf = rt; | |
528c4ceb | 1341 | res = fib6_del(rt, &info); |
1da177e4 LT |
1342 | if (res) { |
1343 | #if RT6_DEBUG >= 2 | |
1344 | printk(KERN_DEBUG "fib6_clean_node: del failed: rt=%p@%p err=%d\n", rt, rt->rt6i_node, res); | |
1345 | #endif | |
1346 | continue; | |
1347 | } | |
1348 | return 0; | |
1349 | } | |
547b792c | 1350 | WARN_ON(res != 0); |
1da177e4 LT |
1351 | } |
1352 | w->leaf = rt; | |
1353 | return 0; | |
1354 | } | |
1355 | ||
1356 | /* | |
1357 | * Convenient frontend to tree walker. | |
1ab1457c | 1358 | * |
1da177e4 LT |
1359 | * func is called on each route. |
1360 | * It may return -1 -> delete this route. | |
1361 | * 0 -> continue walking | |
1362 | * | |
1363 | * prune==1 -> only immediate children of node (certainly, | |
1364 | * ignoring pure split nodes) will be scanned. | |
1365 | */ | |
1366 | ||
ec7d43c2 | 1367 | static void fib6_clean_tree(struct net *net, struct fib6_node *root, |
8ce11e6a AB |
1368 | int (*func)(struct rt6_info *, void *arg), |
1369 | int prune, void *arg) | |
1da177e4 LT |
1370 | { |
1371 | struct fib6_cleaner_t c; | |
1372 | ||
1373 | c.w.root = root; | |
1374 | c.w.func = fib6_clean_node; | |
1375 | c.w.prune = prune; | |
2bec5a36 PM |
1376 | c.w.count = 0; |
1377 | c.w.skip = 0; | |
1da177e4 LT |
1378 | c.func = func; |
1379 | c.arg = arg; | |
ec7d43c2 | 1380 | c.net = net; |
1da177e4 LT |
1381 | |
1382 | fib6_walk(&c.w); | |
1383 | } | |
1384 | ||
f3db4851 | 1385 | void fib6_clean_all(struct net *net, int (*func)(struct rt6_info *, void *arg), |
c71099ac TG |
1386 | int prune, void *arg) |
1387 | { | |
c71099ac | 1388 | struct fib6_table *table; |
1b43af54 | 1389 | struct hlist_node *node; |
58f09b78 | 1390 | struct hlist_head *head; |
1b43af54 | 1391 | unsigned int h; |
c71099ac | 1392 | |
1b43af54 | 1393 | rcu_read_lock(); |
a33bc5c1 | 1394 | for (h = 0; h < FIB6_TABLE_HASHSZ; h++) { |
f3db4851 | 1395 | head = &net->ipv6.fib_table_hash[h]; |
58f09b78 | 1396 | hlist_for_each_entry_rcu(table, node, head, tb6_hlist) { |
c71099ac | 1397 | write_lock_bh(&table->tb6_lock); |
ec7d43c2 BT |
1398 | fib6_clean_tree(net, &table->tb6_root, |
1399 | func, prune, arg); | |
c71099ac TG |
1400 | write_unlock_bh(&table->tb6_lock); |
1401 | } | |
1402 | } | |
1b43af54 | 1403 | rcu_read_unlock(); |
c71099ac TG |
1404 | } |
1405 | ||
1da177e4 LT |
1406 | static int fib6_prune_clone(struct rt6_info *rt, void *arg) |
1407 | { | |
1408 | if (rt->rt6i_flags & RTF_CACHE) { | |
1409 | RT6_TRACE("pruning clone %p\n", rt); | |
1410 | return -1; | |
1411 | } | |
1412 | ||
1413 | return 0; | |
1414 | } | |
1415 | ||
ec7d43c2 BT |
1416 | static void fib6_prune_clones(struct net *net, struct fib6_node *fn, |
1417 | struct rt6_info *rt) | |
1da177e4 | 1418 | { |
ec7d43c2 | 1419 | fib6_clean_tree(net, fn, fib6_prune_clone, 1, rt); |
1da177e4 LT |
1420 | } |
1421 | ||
1422 | /* | |
1423 | * Garbage collection | |
1424 | */ | |
1425 | ||
1426 | static struct fib6_gc_args | |
1427 | { | |
1428 | int timeout; | |
1429 | int more; | |
1430 | } gc_args; | |
1431 | ||
1432 | static int fib6_age(struct rt6_info *rt, void *arg) | |
1433 | { | |
1434 | unsigned long now = jiffies; | |
1435 | ||
1436 | /* | |
1437 | * check addrconf expiration here. | |
1438 | * Routes are expired even if they are in use. | |
1439 | * | |
1440 | * Also age clones. Note, that clones are aged out | |
1441 | * only if they are not in use now. | |
1442 | */ | |
1443 | ||
1444 | if (rt->rt6i_flags&RTF_EXPIRES && rt->rt6i_expires) { | |
1445 | if (time_after(now, rt->rt6i_expires)) { | |
1446 | RT6_TRACE("expiring %p\n", rt); | |
1da177e4 LT |
1447 | return -1; |
1448 | } | |
1449 | gc_args.more++; | |
1450 | } else if (rt->rt6i_flags & RTF_CACHE) { | |
1451 | if (atomic_read(&rt->u.dst.__refcnt) == 0 && | |
1452 | time_after_eq(now, rt->u.dst.lastuse + gc_args.timeout)) { | |
1453 | RT6_TRACE("aging clone %p\n", rt); | |
1454 | return -1; | |
1455 | } else if ((rt->rt6i_flags & RTF_GATEWAY) && | |
1456 | (!(rt->rt6i_nexthop->flags & NTF_ROUTER))) { | |
1457 | RT6_TRACE("purging route %p via non-router but gateway\n", | |
1458 | rt); | |
1459 | return -1; | |
1460 | } | |
1461 | gc_args.more++; | |
1462 | } | |
1463 | ||
1464 | return 0; | |
1465 | } | |
1466 | ||
1467 | static DEFINE_SPINLOCK(fib6_gc_lock); | |
1468 | ||
5b7c931d | 1469 | void fib6_run_gc(unsigned long expires, struct net *net) |
1da177e4 | 1470 | { |
5b7c931d | 1471 | if (expires != ~0UL) { |
1da177e4 | 1472 | spin_lock_bh(&fib6_gc_lock); |
5b7c931d DL |
1473 | gc_args.timeout = expires ? (int)expires : |
1474 | net->ipv6.sysctl.ip6_rt_gc_interval; | |
1da177e4 | 1475 | } else { |
a76d7345 | 1476 | if (!spin_trylock_bh(&fib6_gc_lock)) { |
417f28bb | 1477 | mod_timer(&net->ipv6.ip6_fib_timer, jiffies + HZ); |
1da177e4 LT |
1478 | return; |
1479 | } | |
5b7c931d | 1480 | gc_args.timeout = net->ipv6.sysctl.ip6_rt_gc_interval; |
1da177e4 | 1481 | } |
1da177e4 | 1482 | |
3d0f24a7 | 1483 | gc_args.more = icmp6_dst_gc(); |
f3db4851 | 1484 | |
5b7c931d | 1485 | fib6_clean_all(net, fib6_age, 0, NULL); |
1da177e4 LT |
1486 | |
1487 | if (gc_args.more) | |
c8a45222 SH |
1488 | mod_timer(&net->ipv6.ip6_fib_timer, |
1489 | round_jiffies(jiffies | |
1490 | + net->ipv6.sysctl.ip6_rt_gc_interval)); | |
417f28bb SH |
1491 | else |
1492 | del_timer(&net->ipv6.ip6_fib_timer); | |
1da177e4 LT |
1493 | spin_unlock_bh(&fib6_gc_lock); |
1494 | } | |
1495 | ||
5b7c931d DL |
1496 | static void fib6_gc_timer_cb(unsigned long arg) |
1497 | { | |
1498 | fib6_run_gc(0, (struct net *)arg); | |
1499 | } | |
1500 | ||
2c8c1e72 | 1501 | static int __net_init fib6_net_init(struct net *net) |
1da177e4 | 1502 | { |
417f28bb | 1503 | setup_timer(&net->ipv6.ip6_fib_timer, fib6_gc_timer_cb, (unsigned long)net); |
63152fc0 | 1504 | |
c572872f BT |
1505 | net->ipv6.rt6_stats = kzalloc(sizeof(*net->ipv6.rt6_stats), GFP_KERNEL); |
1506 | if (!net->ipv6.rt6_stats) | |
1507 | goto out_timer; | |
1508 | ||
a33bc5c1 | 1509 | net->ipv6.fib_table_hash = kcalloc(FIB6_TABLE_HASHSZ, |
75307c0f SH |
1510 | sizeof(*net->ipv6.fib_table_hash), |
1511 | GFP_KERNEL); | |
58f09b78 | 1512 | if (!net->ipv6.fib_table_hash) |
c572872f | 1513 | goto out_rt6_stats; |
e0b85590 | 1514 | |
58f09b78 DL |
1515 | net->ipv6.fib6_main_tbl = kzalloc(sizeof(*net->ipv6.fib6_main_tbl), |
1516 | GFP_KERNEL); | |
1517 | if (!net->ipv6.fib6_main_tbl) | |
e0b85590 DL |
1518 | goto out_fib_table_hash; |
1519 | ||
58f09b78 | 1520 | net->ipv6.fib6_main_tbl->tb6_id = RT6_TABLE_MAIN; |
8ed67789 | 1521 | net->ipv6.fib6_main_tbl->tb6_root.leaf = net->ipv6.ip6_null_entry; |
58f09b78 DL |
1522 | net->ipv6.fib6_main_tbl->tb6_root.fn_flags = |
1523 | RTN_ROOT | RTN_TL_ROOT | RTN_RTINFO; | |
e0b85590 DL |
1524 | |
1525 | #ifdef CONFIG_IPV6_MULTIPLE_TABLES | |
58f09b78 DL |
1526 | net->ipv6.fib6_local_tbl = kzalloc(sizeof(*net->ipv6.fib6_local_tbl), |
1527 | GFP_KERNEL); | |
1528 | if (!net->ipv6.fib6_local_tbl) | |
e0b85590 | 1529 | goto out_fib6_main_tbl; |
58f09b78 | 1530 | net->ipv6.fib6_local_tbl->tb6_id = RT6_TABLE_LOCAL; |
8ed67789 | 1531 | net->ipv6.fib6_local_tbl->tb6_root.leaf = net->ipv6.ip6_null_entry; |
58f09b78 DL |
1532 | net->ipv6.fib6_local_tbl->tb6_root.fn_flags = |
1533 | RTN_ROOT | RTN_TL_ROOT | RTN_RTINFO; | |
e0b85590 | 1534 | #endif |
58f09b78 | 1535 | fib6_tables_init(net); |
f845ab6b | 1536 | |
417f28bb | 1537 | return 0; |
d63bddbe | 1538 | |
e0b85590 | 1539 | #ifdef CONFIG_IPV6_MULTIPLE_TABLES |
e0b85590 | 1540 | out_fib6_main_tbl: |
58f09b78 | 1541 | kfree(net->ipv6.fib6_main_tbl); |
e0b85590 | 1542 | #endif |
e0b85590 | 1543 | out_fib_table_hash: |
58f09b78 | 1544 | kfree(net->ipv6.fib_table_hash); |
c572872f BT |
1545 | out_rt6_stats: |
1546 | kfree(net->ipv6.rt6_stats); | |
63152fc0 | 1547 | out_timer: |
417f28bb | 1548 | return -ENOMEM; |
58f09b78 DL |
1549 | } |
1550 | ||
1551 | static void fib6_net_exit(struct net *net) | |
1552 | { | |
8ed67789 | 1553 | rt6_ifdown(net, NULL); |
417f28bb SH |
1554 | del_timer_sync(&net->ipv6.ip6_fib_timer); |
1555 | ||
58f09b78 DL |
1556 | #ifdef CONFIG_IPV6_MULTIPLE_TABLES |
1557 | kfree(net->ipv6.fib6_local_tbl); | |
1558 | #endif | |
1559 | kfree(net->ipv6.fib6_main_tbl); | |
1560 | kfree(net->ipv6.fib_table_hash); | |
c572872f | 1561 | kfree(net->ipv6.rt6_stats); |
58f09b78 DL |
1562 | } |
1563 | ||
1564 | static struct pernet_operations fib6_net_ops = { | |
1565 | .init = fib6_net_init, | |
1566 | .exit = fib6_net_exit, | |
1567 | }; | |
1568 | ||
1569 | int __init fib6_init(void) | |
1570 | { | |
1571 | int ret = -ENOMEM; | |
63152fc0 | 1572 | |
58f09b78 DL |
1573 | fib6_node_kmem = kmem_cache_create("fib6_nodes", |
1574 | sizeof(struct fib6_node), | |
1575 | 0, SLAB_HWCACHE_ALIGN, | |
1576 | NULL); | |
1577 | if (!fib6_node_kmem) | |
1578 | goto out; | |
1579 | ||
1580 | ret = register_pernet_subsys(&fib6_net_ops); | |
1581 | if (ret) | |
c572872f | 1582 | goto out_kmem_cache_create; |
58f09b78 DL |
1583 | |
1584 | ret = __rtnl_register(PF_INET6, RTM_GETROUTE, NULL, inet6_dump_fib); | |
1585 | if (ret) | |
1586 | goto out_unregister_subsys; | |
1587 | out: | |
1588 | return ret; | |
1589 | ||
1590 | out_unregister_subsys: | |
1591 | unregister_pernet_subsys(&fib6_net_ops); | |
d63bddbe DL |
1592 | out_kmem_cache_create: |
1593 | kmem_cache_destroy(fib6_node_kmem); | |
1594 | goto out; | |
1da177e4 LT |
1595 | } |
1596 | ||
1597 | void fib6_gc_cleanup(void) | |
1598 | { | |
58f09b78 | 1599 | unregister_pernet_subsys(&fib6_net_ops); |
1da177e4 LT |
1600 | kmem_cache_destroy(fib6_node_kmem); |
1601 | } |