blob: 107bb6cbb0b370be0f8e10b0d434a432fbc3ebdd [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * INET An implementation of the TCP/IP protocol suite for the LINUX
3 * operating system. INET is implemented using the BSD Socket
4 * interface as the means of communication with the user level.
5 *
6 * IPv4 FIB: lookup engine and maintenance routines.
7 *
8 * Version: $Id: fib_hash.c,v 1.13 2001/10/31 21:55:54 davem Exp $
9 *
10 * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
11 *
12 * This program is free software; you can redistribute it and/or
13 * modify it under the terms of the GNU General Public License
14 * as published by the Free Software Foundation; either version
15 * 2 of the License, or (at your option) any later version.
16 */
17
Linus Torvalds1da177e2005-04-16 15:20:36 -070018#include <asm/uaccess.h>
19#include <asm/system.h>
20#include <linux/bitops.h>
21#include <linux/types.h>
22#include <linux/kernel.h>
23#include <linux/sched.h>
24#include <linux/mm.h>
25#include <linux/string.h>
26#include <linux/socket.h>
27#include <linux/sockios.h>
28#include <linux/errno.h>
29#include <linux/in.h>
30#include <linux/inet.h>
Arnaldo Carvalho de Melo14c85022005-12-27 02:43:12 -020031#include <linux/inetdevice.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070032#include <linux/netdevice.h>
33#include <linux/if_arp.h>
34#include <linux/proc_fs.h>
35#include <linux/skbuff.h>
36#include <linux/netlink.h>
37#include <linux/init.h>
38
39#include <net/ip.h>
40#include <net/protocol.h>
41#include <net/route.h>
42#include <net/tcp.h>
43#include <net/sock.h>
44#include <net/ip_fib.h>
45
46#include "fib_lookup.h"
47
Eric Dumazetba899662005-08-26 12:05:31 -070048static kmem_cache_t *fn_hash_kmem __read_mostly;
49static kmem_cache_t *fn_alias_kmem __read_mostly;
Linus Torvalds1da177e2005-04-16 15:20:36 -070050
51struct fib_node {
52 struct hlist_node fn_hash;
53 struct list_head fn_alias;
Al Virob6e80c62006-09-26 22:20:01 -070054 __be32 fn_key;
Linus Torvalds1da177e2005-04-16 15:20:36 -070055};
56
57struct fn_zone {
58 struct fn_zone *fz_next; /* Next not empty zone */
59 struct hlist_head *fz_hash; /* Hash table pointer */
60 int fz_nent; /* Number of entries */
61
62 int fz_divisor; /* Hash divisor */
63 u32 fz_hashmask; /* (fz_divisor - 1) */
64#define FZ_HASHMASK(fz) ((fz)->fz_hashmask)
65
66 int fz_order; /* Zone order */
Al Virob6e80c62006-09-26 22:20:01 -070067 __be32 fz_mask;
Linus Torvalds1da177e2005-04-16 15:20:36 -070068#define FZ_MASK(fz) ((fz)->fz_mask)
69};
70
71/* NOTE. On fast computers evaluation of fz_hashmask and fz_mask
72 * can be cheaper than memory lookup, so that FZ_* macros are used.
73 */
74
75struct fn_hash {
76 struct fn_zone *fn_zones[33];
77 struct fn_zone *fn_zone_list;
78};
79
Al Virob6e80c62006-09-26 22:20:01 -070080static inline u32 fn_hash(__be32 key, struct fn_zone *fz)
Linus Torvalds1da177e2005-04-16 15:20:36 -070081{
82 u32 h = ntohl(key)>>(32 - fz->fz_order);
83 h ^= (h>>20);
84 h ^= (h>>10);
85 h ^= (h>>5);
86 h &= FZ_HASHMASK(fz);
87 return h;
88}
89
Al Virob6e80c62006-09-26 22:20:01 -070090static inline __be32 fz_key(__be32 dst, struct fn_zone *fz)
Linus Torvalds1da177e2005-04-16 15:20:36 -070091{
92 return dst & FZ_MASK(fz);
93}
94
95static DEFINE_RWLOCK(fib_hash_lock);
96static unsigned int fib_hash_genid;
97
98#define FZ_MAX_DIVISOR ((PAGE_SIZE<<MAX_ORDER) / sizeof(struct hlist_head))
99
100static struct hlist_head *fz_hash_alloc(int divisor)
101{
102 unsigned long size = divisor * sizeof(struct hlist_head);
103
104 if (size <= PAGE_SIZE) {
105 return kmalloc(size, GFP_KERNEL);
106 } else {
107 return (struct hlist_head *)
108 __get_free_pages(GFP_KERNEL, get_order(size));
109 }
110}
111
112/* The fib hash lock must be held when this is called. */
113static inline void fn_rebuild_zone(struct fn_zone *fz,
114 struct hlist_head *old_ht,
115 int old_divisor)
116{
117 int i;
118
119 for (i = 0; i < old_divisor; i++) {
120 struct hlist_node *node, *n;
121 struct fib_node *f;
122
123 hlist_for_each_entry_safe(f, node, n, &old_ht[i], fn_hash) {
124 struct hlist_head *new_head;
125
126 hlist_del(&f->fn_hash);
127
128 new_head = &fz->fz_hash[fn_hash(f->fn_key, fz)];
129 hlist_add_head(&f->fn_hash, new_head);
130 }
131 }
132}
133
134static void fz_hash_free(struct hlist_head *hash, int divisor)
135{
136 unsigned long size = divisor * sizeof(struct hlist_head);
137
138 if (size <= PAGE_SIZE)
139 kfree(hash);
140 else
141 free_pages((unsigned long)hash, get_order(size));
142}
143
144static void fn_rehash_zone(struct fn_zone *fz)
145{
146 struct hlist_head *ht, *old_ht;
147 int old_divisor, new_divisor;
148 u32 new_hashmask;
149
150 old_divisor = fz->fz_divisor;
151
152 switch (old_divisor) {
153 case 16:
154 new_divisor = 256;
155 break;
156 case 256:
157 new_divisor = 1024;
158 break;
159 default:
160 if ((old_divisor << 1) > FZ_MAX_DIVISOR) {
161 printk(KERN_CRIT "route.c: bad divisor %d!\n", old_divisor);
162 return;
163 }
164 new_divisor = (old_divisor << 1);
165 break;
166 }
167
168 new_hashmask = (new_divisor - 1);
169
170#if RT_CACHE_DEBUG >= 2
171 printk("fn_rehash_zone: hash for zone %d grows from %d\n", fz->fz_order, old_divisor);
172#endif
173
174 ht = fz_hash_alloc(new_divisor);
175
176 if (ht) {
177 memset(ht, 0, new_divisor * sizeof(struct hlist_head));
178
179 write_lock_bh(&fib_hash_lock);
180 old_ht = fz->fz_hash;
181 fz->fz_hash = ht;
182 fz->fz_hashmask = new_hashmask;
183 fz->fz_divisor = new_divisor;
184 fn_rebuild_zone(fz, old_ht, old_divisor);
185 fib_hash_genid++;
186 write_unlock_bh(&fib_hash_lock);
187
188 fz_hash_free(old_ht, old_divisor);
189 }
190}
191
192static inline void fn_free_node(struct fib_node * f)
193{
194 kmem_cache_free(fn_hash_kmem, f);
195}
196
197static inline void fn_free_alias(struct fib_alias *fa)
198{
199 fib_release_info(fa->fa_info);
200 kmem_cache_free(fn_alias_kmem, fa);
201}
202
203static struct fn_zone *
204fn_new_zone(struct fn_hash *table, int z)
205{
206 int i;
Panagiotis Issaris0da974f2006-07-21 14:51:30 -0700207 struct fn_zone *fz = kzalloc(sizeof(struct fn_zone), GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700208 if (!fz)
209 return NULL;
210
Linus Torvalds1da177e2005-04-16 15:20:36 -0700211 if (z) {
212 fz->fz_divisor = 16;
213 } else {
214 fz->fz_divisor = 1;
215 }
216 fz->fz_hashmask = (fz->fz_divisor - 1);
217 fz->fz_hash = fz_hash_alloc(fz->fz_divisor);
218 if (!fz->fz_hash) {
219 kfree(fz);
220 return NULL;
221 }
222 memset(fz->fz_hash, 0, fz->fz_divisor * sizeof(struct hlist_head *));
223 fz->fz_order = z;
224 fz->fz_mask = inet_make_mask(z);
225
226 /* Find the first not empty zone with more specific mask */
227 for (i=z+1; i<=32; i++)
228 if (table->fn_zones[i])
229 break;
230 write_lock_bh(&fib_hash_lock);
231 if (i>32) {
232 /* No more specific masks, we are the first. */
233 fz->fz_next = table->fn_zone_list;
234 table->fn_zone_list = fz;
235 } else {
236 fz->fz_next = table->fn_zones[i]->fz_next;
237 table->fn_zones[i]->fz_next = fz;
238 }
239 table->fn_zones[z] = fz;
240 fib_hash_genid++;
241 write_unlock_bh(&fib_hash_lock);
242 return fz;
243}
244
245static int
246fn_hash_lookup(struct fib_table *tb, const struct flowi *flp, struct fib_result *res)
247{
248 int err;
249 struct fn_zone *fz;
250 struct fn_hash *t = (struct fn_hash*)tb->tb_data;
251
252 read_lock(&fib_hash_lock);
253 for (fz = t->fn_zone_list; fz; fz = fz->fz_next) {
254 struct hlist_head *head;
255 struct hlist_node *node;
256 struct fib_node *f;
Al Virob6e80c62006-09-26 22:20:01 -0700257 __be32 k = fz_key(flp->fl4_dst, fz);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700258
259 head = &fz->fz_hash[fn_hash(k, fz)];
260 hlist_for_each_entry(f, node, head, fn_hash) {
261 if (f->fn_key != k)
262 continue;
263
264 err = fib_semantic_match(&f->fn_alias,
265 flp, res,
266 f->fn_key, fz->fz_mask,
267 fz->fz_order);
268 if (err <= 0)
269 goto out;
270 }
271 }
272 err = 1;
273out:
274 read_unlock(&fib_hash_lock);
275 return err;
276}
277
278static int fn_hash_last_dflt=-1;
279
280static void
281fn_hash_select_default(struct fib_table *tb, const struct flowi *flp, struct fib_result *res)
282{
283 int order, last_idx;
284 struct hlist_node *node;
285 struct fib_node *f;
286 struct fib_info *fi = NULL;
287 struct fib_info *last_resort;
288 struct fn_hash *t = (struct fn_hash*)tb->tb_data;
289 struct fn_zone *fz = t->fn_zones[0];
290
291 if (fz == NULL)
292 return;
293
294 last_idx = -1;
295 last_resort = NULL;
296 order = -1;
297
298 read_lock(&fib_hash_lock);
299 hlist_for_each_entry(f, node, &fz->fz_hash[0], fn_hash) {
300 struct fib_alias *fa;
301
302 list_for_each_entry(fa, &f->fn_alias, fa_list) {
303 struct fib_info *next_fi = fa->fa_info;
304
305 if (fa->fa_scope != res->scope ||
306 fa->fa_type != RTN_UNICAST)
307 continue;
308
309 if (next_fi->fib_priority > res->fi->fib_priority)
310 break;
311 if (!next_fi->fib_nh[0].nh_gw ||
312 next_fi->fib_nh[0].nh_scope != RT_SCOPE_LINK)
313 continue;
314 fa->fa_state |= FA_S_ACCESSED;
315
316 if (fi == NULL) {
317 if (next_fi != res->fi)
318 break;
319 } else if (!fib_detect_death(fi, order, &last_resort,
320 &last_idx, &fn_hash_last_dflt)) {
321 if (res->fi)
322 fib_info_put(res->fi);
323 res->fi = fi;
324 atomic_inc(&fi->fib_clntref);
325 fn_hash_last_dflt = order;
326 goto out;
327 }
328 fi = next_fi;
329 order++;
330 }
331 }
332
333 if (order <= 0 || fi == NULL) {
334 fn_hash_last_dflt = -1;
335 goto out;
336 }
337
338 if (!fib_detect_death(fi, order, &last_resort, &last_idx, &fn_hash_last_dflt)) {
339 if (res->fi)
340 fib_info_put(res->fi);
341 res->fi = fi;
342 atomic_inc(&fi->fib_clntref);
343 fn_hash_last_dflt = order;
344 goto out;
345 }
346
347 if (last_idx >= 0) {
348 if (res->fi)
349 fib_info_put(res->fi);
350 res->fi = last_resort;
351 if (last_resort)
352 atomic_inc(&last_resort->fib_clntref);
353 }
354 fn_hash_last_dflt = last_idx;
355out:
356 read_unlock(&fib_hash_lock);
357}
358
359/* Insert node F to FZ. */
360static inline void fib_insert_node(struct fn_zone *fz, struct fib_node *f)
361{
362 struct hlist_head *head = &fz->fz_hash[fn_hash(f->fn_key, fz)];
363
364 hlist_add_head(&f->fn_hash, head);
365}
366
367/* Return the node in FZ matching KEY. */
Al Virob6e80c62006-09-26 22:20:01 -0700368static struct fib_node *fib_find_node(struct fn_zone *fz, __be32 key)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700369{
370 struct hlist_head *head = &fz->fz_hash[fn_hash(key, fz)];
371 struct hlist_node *node;
372 struct fib_node *f;
373
374 hlist_for_each_entry(f, node, head, fn_hash) {
375 if (f->fn_key == key)
376 return f;
377 }
378
379 return NULL;
380}
381
Thomas Graf4e902c52006-08-17 18:14:52 -0700382static int fn_hash_insert(struct fib_table *tb, struct fib_config *cfg)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700383{
384 struct fn_hash *table = (struct fn_hash *) tb->tb_data;
385 struct fib_node *new_f, *f;
386 struct fib_alias *fa, *new_fa;
387 struct fn_zone *fz;
388 struct fib_info *fi;
Thomas Graf4e902c52006-08-17 18:14:52 -0700389 u8 tos = cfg->fc_tos;
Al Virob6e80c62006-09-26 22:20:01 -0700390 __be32 key;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700391 int err;
392
Thomas Graf4e902c52006-08-17 18:14:52 -0700393 if (cfg->fc_dst_len > 32)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700394 return -EINVAL;
Thomas Graf4e902c52006-08-17 18:14:52 -0700395
396 fz = table->fn_zones[cfg->fc_dst_len];
397 if (!fz && !(fz = fn_new_zone(table, cfg->fc_dst_len)))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700398 return -ENOBUFS;
399
400 key = 0;
Thomas Graf4e902c52006-08-17 18:14:52 -0700401 if (cfg->fc_dst) {
402 if (cfg->fc_dst & ~FZ_MASK(fz))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700403 return -EINVAL;
Thomas Graf4e902c52006-08-17 18:14:52 -0700404 key = fz_key(cfg->fc_dst, fz);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700405 }
406
Thomas Graf4e902c52006-08-17 18:14:52 -0700407 fi = fib_create_info(cfg);
408 if (IS_ERR(fi))
409 return PTR_ERR(fi);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700410
411 if (fz->fz_nent > (fz->fz_divisor<<1) &&
412 fz->fz_divisor < FZ_MAX_DIVISOR &&
Thomas Graf4e902c52006-08-17 18:14:52 -0700413 (cfg->fc_dst_len == 32 ||
414 (1 << cfg->fc_dst_len) > fz->fz_divisor))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700415 fn_rehash_zone(fz);
416
417 f = fib_find_node(fz, key);
418
419 if (!f)
420 fa = NULL;
421 else
422 fa = fib_find_alias(&f->fn_alias, tos, fi->fib_priority);
423
424 /* Now fa, if non-NULL, points to the first fib alias
425 * with the same keys [prefix,tos,priority], if such key already
426 * exists or to the node before which we will insert new one.
427 *
428 * If fa is NULL, we will need to allocate a new one and
429 * insert to the head of f.
430 *
431 * If f is NULL, no fib node matched the destination key
432 * and we need to allocate a new one of those as well.
433 */
434
435 if (fa && fa->fa_tos == tos &&
436 fa->fa_info->fib_priority == fi->fib_priority) {
437 struct fib_alias *fa_orig;
438
439 err = -EEXIST;
Thomas Graf4e902c52006-08-17 18:14:52 -0700440 if (cfg->fc_nlflags & NLM_F_EXCL)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700441 goto out;
442
Thomas Graf4e902c52006-08-17 18:14:52 -0700443 if (cfg->fc_nlflags & NLM_F_REPLACE) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700444 struct fib_info *fi_drop;
445 u8 state;
446
447 write_lock_bh(&fib_hash_lock);
448 fi_drop = fa->fa_info;
449 fa->fa_info = fi;
Thomas Graf4e902c52006-08-17 18:14:52 -0700450 fa->fa_type = cfg->fc_type;
451 fa->fa_scope = cfg->fc_scope;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700452 state = fa->fa_state;
453 fa->fa_state &= ~FA_S_ACCESSED;
454 fib_hash_genid++;
455 write_unlock_bh(&fib_hash_lock);
456
457 fib_release_info(fi_drop);
458 if (state & FA_S_ACCESSED)
459 rt_cache_flush(-1);
460 return 0;
461 }
462
463 /* Error if we find a perfect match which
464 * uses the same scope, type, and nexthop
465 * information.
466 */
467 fa_orig = fa;
468 fa = list_entry(fa->fa_list.prev, struct fib_alias, fa_list);
469 list_for_each_entry_continue(fa, &f->fn_alias, fa_list) {
470 if (fa->fa_tos != tos)
471 break;
472 if (fa->fa_info->fib_priority != fi->fib_priority)
473 break;
Thomas Graf4e902c52006-08-17 18:14:52 -0700474 if (fa->fa_type == cfg->fc_type &&
475 fa->fa_scope == cfg->fc_scope &&
Linus Torvalds1da177e2005-04-16 15:20:36 -0700476 fa->fa_info == fi)
477 goto out;
478 }
Thomas Graf4e902c52006-08-17 18:14:52 -0700479 if (!(cfg->fc_nlflags & NLM_F_APPEND))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700480 fa = fa_orig;
481 }
482
483 err = -ENOENT;
Thomas Graf4e902c52006-08-17 18:14:52 -0700484 if (!(cfg->fc_nlflags & NLM_F_CREATE))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700485 goto out;
486
487 err = -ENOBUFS;
488 new_fa = kmem_cache_alloc(fn_alias_kmem, SLAB_KERNEL);
489 if (new_fa == NULL)
490 goto out;
491
492 new_f = NULL;
493 if (!f) {
494 new_f = kmem_cache_alloc(fn_hash_kmem, SLAB_KERNEL);
495 if (new_f == NULL)
496 goto out_free_new_fa;
497
498 INIT_HLIST_NODE(&new_f->fn_hash);
499 INIT_LIST_HEAD(&new_f->fn_alias);
500 new_f->fn_key = key;
501 f = new_f;
502 }
503
504 new_fa->fa_info = fi;
505 new_fa->fa_tos = tos;
Thomas Graf4e902c52006-08-17 18:14:52 -0700506 new_fa->fa_type = cfg->fc_type;
507 new_fa->fa_scope = cfg->fc_scope;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700508 new_fa->fa_state = 0;
509
510 /*
511 * Insert new entry to the list.
512 */
513
514 write_lock_bh(&fib_hash_lock);
515 if (new_f)
516 fib_insert_node(fz, new_f);
517 list_add_tail(&new_fa->fa_list,
518 (fa ? &fa->fa_list : &f->fn_alias));
519 fib_hash_genid++;
520 write_unlock_bh(&fib_hash_lock);
521
522 if (new_f)
523 fz->fz_nent++;
524 rt_cache_flush(-1);
525
Thomas Graf4e902c52006-08-17 18:14:52 -0700526 rtmsg_fib(RTM_NEWROUTE, key, new_fa, cfg->fc_dst_len, tb->tb_id,
527 &cfg->fc_nlinfo);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700528 return 0;
529
530out_free_new_fa:
531 kmem_cache_free(fn_alias_kmem, new_fa);
532out:
533 fib_release_info(fi);
534 return err;
535}
536
537
Thomas Graf4e902c52006-08-17 18:14:52 -0700538static int fn_hash_delete(struct fib_table *tb, struct fib_config *cfg)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700539{
540 struct fn_hash *table = (struct fn_hash*)tb->tb_data;
541 struct fib_node *f;
542 struct fib_alias *fa, *fa_to_delete;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700543 struct fn_zone *fz;
Al Virob6e80c62006-09-26 22:20:01 -0700544 __be32 key;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700545
Thomas Graf4e902c52006-08-17 18:14:52 -0700546 if (cfg->fc_dst_len > 32)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700547 return -EINVAL;
Thomas Graf4e902c52006-08-17 18:14:52 -0700548
549 if ((fz = table->fn_zones[cfg->fc_dst_len]) == NULL)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700550 return -ESRCH;
551
552 key = 0;
Thomas Graf4e902c52006-08-17 18:14:52 -0700553 if (cfg->fc_dst) {
554 if (cfg->fc_dst & ~FZ_MASK(fz))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700555 return -EINVAL;
Thomas Graf4e902c52006-08-17 18:14:52 -0700556 key = fz_key(cfg->fc_dst, fz);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700557 }
558
559 f = fib_find_node(fz, key);
560
561 if (!f)
562 fa = NULL;
563 else
Thomas Graf4e902c52006-08-17 18:14:52 -0700564 fa = fib_find_alias(&f->fn_alias, cfg->fc_tos, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700565 if (!fa)
566 return -ESRCH;
567
568 fa_to_delete = NULL;
569 fa = list_entry(fa->fa_list.prev, struct fib_alias, fa_list);
570 list_for_each_entry_continue(fa, &f->fn_alias, fa_list) {
571 struct fib_info *fi = fa->fa_info;
572
Thomas Graf4e902c52006-08-17 18:14:52 -0700573 if (fa->fa_tos != cfg->fc_tos)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700574 break;
575
Thomas Graf4e902c52006-08-17 18:14:52 -0700576 if ((!cfg->fc_type ||
577 fa->fa_type == cfg->fc_type) &&
578 (cfg->fc_scope == RT_SCOPE_NOWHERE ||
579 fa->fa_scope == cfg->fc_scope) &&
580 (!cfg->fc_protocol ||
581 fi->fib_protocol == cfg->fc_protocol) &&
582 fib_nh_match(cfg, fi) == 0) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700583 fa_to_delete = fa;
584 break;
585 }
586 }
587
588 if (fa_to_delete) {
589 int kill_fn;
590
591 fa = fa_to_delete;
Thomas Graf4e902c52006-08-17 18:14:52 -0700592 rtmsg_fib(RTM_DELROUTE, key, fa, cfg->fc_dst_len,
593 tb->tb_id, &cfg->fc_nlinfo);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700594
595 kill_fn = 0;
596 write_lock_bh(&fib_hash_lock);
597 list_del(&fa->fa_list);
598 if (list_empty(&f->fn_alias)) {
599 hlist_del(&f->fn_hash);
600 kill_fn = 1;
601 }
602 fib_hash_genid++;
603 write_unlock_bh(&fib_hash_lock);
604
605 if (fa->fa_state & FA_S_ACCESSED)
606 rt_cache_flush(-1);
607 fn_free_alias(fa);
608 if (kill_fn) {
609 fn_free_node(f);
610 fz->fz_nent--;
611 }
612
613 return 0;
614 }
615 return -ESRCH;
616}
617
618static int fn_flush_list(struct fn_zone *fz, int idx)
619{
620 struct hlist_head *head = &fz->fz_hash[idx];
621 struct hlist_node *node, *n;
622 struct fib_node *f;
623 int found = 0;
624
625 hlist_for_each_entry_safe(f, node, n, head, fn_hash) {
626 struct fib_alias *fa, *fa_node;
627 int kill_f;
628
629 kill_f = 0;
630 list_for_each_entry_safe(fa, fa_node, &f->fn_alias, fa_list) {
631 struct fib_info *fi = fa->fa_info;
632
633 if (fi && (fi->fib_flags&RTNH_F_DEAD)) {
634 write_lock_bh(&fib_hash_lock);
635 list_del(&fa->fa_list);
636 if (list_empty(&f->fn_alias)) {
637 hlist_del(&f->fn_hash);
638 kill_f = 1;
639 }
640 fib_hash_genid++;
641 write_unlock_bh(&fib_hash_lock);
642
643 fn_free_alias(fa);
644 found++;
645 }
646 }
647 if (kill_f) {
648 fn_free_node(f);
649 fz->fz_nent--;
650 }
651 }
652 return found;
653}
654
655static int fn_hash_flush(struct fib_table *tb)
656{
657 struct fn_hash *table = (struct fn_hash *) tb->tb_data;
658 struct fn_zone *fz;
659 int found = 0;
660
661 for (fz = table->fn_zone_list; fz; fz = fz->fz_next) {
662 int i;
663
664 for (i = fz->fz_divisor - 1; i >= 0; i--)
665 found += fn_flush_list(fz, i);
666 }
667 return found;
668}
669
670
671static inline int
672fn_hash_dump_bucket(struct sk_buff *skb, struct netlink_callback *cb,
673 struct fib_table *tb,
674 struct fn_zone *fz,
675 struct hlist_head *head)
676{
677 struct hlist_node *node;
678 struct fib_node *f;
679 int i, s_i;
680
Patrick McHardy1af5a8c2006-08-10 23:10:46 -0700681 s_i = cb->args[4];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700682 i = 0;
683 hlist_for_each_entry(f, node, head, fn_hash) {
684 struct fib_alias *fa;
685
686 list_for_each_entry(fa, &f->fn_alias, fa_list) {
687 if (i < s_i)
688 goto next;
689
690 if (fib_dump_info(skb, NETLINK_CB(cb->skb).pid,
691 cb->nlh->nlmsg_seq,
692 RTM_NEWROUTE,
693 tb->tb_id,
694 fa->fa_type,
695 fa->fa_scope,
Thomas Grafbe403ea2006-08-17 18:15:17 -0700696 f->fn_key,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700697 fz->fz_order,
698 fa->fa_tos,
Jamal Hadi Salimb6544c02005-06-18 22:54:12 -0700699 fa->fa_info,
700 NLM_F_MULTI) < 0) {
Patrick McHardy1af5a8c2006-08-10 23:10:46 -0700701 cb->args[4] = i;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700702 return -1;
703 }
704 next:
705 i++;
706 }
707 }
Patrick McHardy1af5a8c2006-08-10 23:10:46 -0700708 cb->args[4] = i;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700709 return skb->len;
710}
711
712static inline int
713fn_hash_dump_zone(struct sk_buff *skb, struct netlink_callback *cb,
714 struct fib_table *tb,
715 struct fn_zone *fz)
716{
717 int h, s_h;
718
Patrick McHardy1af5a8c2006-08-10 23:10:46 -0700719 s_h = cb->args[3];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700720 for (h=0; h < fz->fz_divisor; h++) {
721 if (h < s_h) continue;
722 if (h > s_h)
Patrick McHardy1af5a8c2006-08-10 23:10:46 -0700723 memset(&cb->args[4], 0,
724 sizeof(cb->args) - 4*sizeof(cb->args[0]));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700725 if (fz->fz_hash == NULL ||
726 hlist_empty(&fz->fz_hash[h]))
727 continue;
728 if (fn_hash_dump_bucket(skb, cb, tb, fz, &fz->fz_hash[h])<0) {
Patrick McHardy1af5a8c2006-08-10 23:10:46 -0700729 cb->args[3] = h;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700730 return -1;
731 }
732 }
Patrick McHardy1af5a8c2006-08-10 23:10:46 -0700733 cb->args[3] = h;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700734 return skb->len;
735}
736
737static int fn_hash_dump(struct fib_table *tb, struct sk_buff *skb, struct netlink_callback *cb)
738{
739 int m, s_m;
740 struct fn_zone *fz;
741 struct fn_hash *table = (struct fn_hash*)tb->tb_data;
742
Patrick McHardy1af5a8c2006-08-10 23:10:46 -0700743 s_m = cb->args[2];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700744 read_lock(&fib_hash_lock);
745 for (fz = table->fn_zone_list, m=0; fz; fz = fz->fz_next, m++) {
746 if (m < s_m) continue;
747 if (m > s_m)
Patrick McHardy1af5a8c2006-08-10 23:10:46 -0700748 memset(&cb->args[3], 0,
749 sizeof(cb->args) - 3*sizeof(cb->args[0]));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700750 if (fn_hash_dump_zone(skb, cb, tb, fz) < 0) {
Patrick McHardy1af5a8c2006-08-10 23:10:46 -0700751 cb->args[2] = m;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700752 read_unlock(&fib_hash_lock);
753 return -1;
754 }
755 }
756 read_unlock(&fib_hash_lock);
Patrick McHardy1af5a8c2006-08-10 23:10:46 -0700757 cb->args[2] = m;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700758 return skb->len;
759}
760
761#ifdef CONFIG_IP_MULTIPLE_TABLES
Patrick McHardy2dfe55b2006-08-10 23:08:33 -0700762struct fib_table * fib_hash_init(u32 id)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700763#else
Patrick McHardy2dfe55b2006-08-10 23:08:33 -0700764struct fib_table * __init fib_hash_init(u32 id)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700765#endif
766{
767 struct fib_table *tb;
768
769 if (fn_hash_kmem == NULL)
770 fn_hash_kmem = kmem_cache_create("ip_fib_hash",
771 sizeof(struct fib_node),
772 0, SLAB_HWCACHE_ALIGN,
773 NULL, NULL);
774
775 if (fn_alias_kmem == NULL)
776 fn_alias_kmem = kmem_cache_create("ip_fib_alias",
777 sizeof(struct fib_alias),
778 0, SLAB_HWCACHE_ALIGN,
779 NULL, NULL);
780
781 tb = kmalloc(sizeof(struct fib_table) + sizeof(struct fn_hash),
782 GFP_KERNEL);
783 if (tb == NULL)
784 return NULL;
785
786 tb->tb_id = id;
787 tb->tb_lookup = fn_hash_lookup;
788 tb->tb_insert = fn_hash_insert;
789 tb->tb_delete = fn_hash_delete;
790 tb->tb_flush = fn_hash_flush;
791 tb->tb_select_default = fn_hash_select_default;
792 tb->tb_dump = fn_hash_dump;
793 memset(tb->tb_data, 0, sizeof(struct fn_hash));
794 return tb;
795}
796
797/* ------------------------------------------------------------------------ */
798#ifdef CONFIG_PROC_FS
799
800struct fib_iter_state {
801 struct fn_zone *zone;
802 int bucket;
803 struct hlist_head *hash_head;
804 struct fib_node *fn;
805 struct fib_alias *fa;
806 loff_t pos;
807 unsigned int genid;
808 int valid;
809};
810
811static struct fib_alias *fib_get_first(struct seq_file *seq)
812{
813 struct fib_iter_state *iter = seq->private;
814 struct fn_hash *table = (struct fn_hash *) ip_fib_main_table->tb_data;
815
816 iter->bucket = 0;
817 iter->hash_head = NULL;
818 iter->fn = NULL;
819 iter->fa = NULL;
820 iter->pos = 0;
821 iter->genid = fib_hash_genid;
822 iter->valid = 1;
823
824 for (iter->zone = table->fn_zone_list; iter->zone;
825 iter->zone = iter->zone->fz_next) {
826 int maxslot;
827
828 if (!iter->zone->fz_nent)
829 continue;
830
831 iter->hash_head = iter->zone->fz_hash;
832 maxslot = iter->zone->fz_divisor;
833
834 for (iter->bucket = 0; iter->bucket < maxslot;
835 ++iter->bucket, ++iter->hash_head) {
836 struct hlist_node *node;
837 struct fib_node *fn;
838
839 hlist_for_each_entry(fn,node,iter->hash_head,fn_hash) {
840 struct fib_alias *fa;
841
842 list_for_each_entry(fa,&fn->fn_alias,fa_list) {
843 iter->fn = fn;
844 iter->fa = fa;
845 goto out;
846 }
847 }
848 }
849 }
850out:
851 return iter->fa;
852}
853
854static struct fib_alias *fib_get_next(struct seq_file *seq)
855{
856 struct fib_iter_state *iter = seq->private;
857 struct fib_node *fn;
858 struct fib_alias *fa;
859
860 /* Advance FA, if any. */
861 fn = iter->fn;
862 fa = iter->fa;
863 if (fa) {
864 BUG_ON(!fn);
865 list_for_each_entry_continue(fa, &fn->fn_alias, fa_list) {
866 iter->fa = fa;
867 goto out;
868 }
869 }
870
871 fa = iter->fa = NULL;
872
873 /* Advance FN. */
874 if (fn) {
875 struct hlist_node *node = &fn->fn_hash;
876 hlist_for_each_entry_continue(fn, node, fn_hash) {
877 iter->fn = fn;
878
879 list_for_each_entry(fa, &fn->fn_alias, fa_list) {
880 iter->fa = fa;
881 goto out;
882 }
883 }
884 }
885
886 fn = iter->fn = NULL;
887
888 /* Advance hash chain. */
889 if (!iter->zone)
890 goto out;
891
892 for (;;) {
893 struct hlist_node *node;
894 int maxslot;
895
896 maxslot = iter->zone->fz_divisor;
897
898 while (++iter->bucket < maxslot) {
899 iter->hash_head++;
900
901 hlist_for_each_entry(fn, node, iter->hash_head, fn_hash) {
902 list_for_each_entry(fa, &fn->fn_alias, fa_list) {
903 iter->fn = fn;
904 iter->fa = fa;
905 goto out;
906 }
907 }
908 }
909
910 iter->zone = iter->zone->fz_next;
911
912 if (!iter->zone)
913 goto out;
914
915 iter->bucket = 0;
916 iter->hash_head = iter->zone->fz_hash;
917
918 hlist_for_each_entry(fn, node, iter->hash_head, fn_hash) {
919 list_for_each_entry(fa, &fn->fn_alias, fa_list) {
920 iter->fn = fn;
921 iter->fa = fa;
922 goto out;
923 }
924 }
925 }
926out:
927 iter->pos++;
928 return fa;
929}
930
931static struct fib_alias *fib_get_idx(struct seq_file *seq, loff_t pos)
932{
933 struct fib_iter_state *iter = seq->private;
934 struct fib_alias *fa;
935
936 if (iter->valid && pos >= iter->pos && iter->genid == fib_hash_genid) {
937 fa = iter->fa;
938 pos -= iter->pos;
939 } else
940 fa = fib_get_first(seq);
941
942 if (fa)
943 while (pos && (fa = fib_get_next(seq)))
944 --pos;
945 return pos ? NULL : fa;
946}
947
948static void *fib_seq_start(struct seq_file *seq, loff_t *pos)
949{
950 void *v = NULL;
951
952 read_lock(&fib_hash_lock);
953 if (ip_fib_main_table)
954 v = *pos ? fib_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
955 return v;
956}
957
958static void *fib_seq_next(struct seq_file *seq, void *v, loff_t *pos)
959{
960 ++*pos;
961 return v == SEQ_START_TOKEN ? fib_get_first(seq) : fib_get_next(seq);
962}
963
964static void fib_seq_stop(struct seq_file *seq, void *v)
965{
966 read_unlock(&fib_hash_lock);
967}
968
Al Virob6e80c62006-09-26 22:20:01 -0700969static unsigned fib_flag_trans(int type, __be32 mask, struct fib_info *fi)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700970{
Arjan van de Ven9b5b5cf2005-11-29 16:21:38 -0800971 static const unsigned type2flags[RTN_MAX + 1] = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700972 [7] = RTF_REJECT, [8] = RTF_REJECT,
973 };
974 unsigned flags = type2flags[type];
975
976 if (fi && fi->fib_nh->nh_gw)
977 flags |= RTF_GATEWAY;
Al Virob6e80c62006-09-26 22:20:01 -0700978 if (mask == htonl(0xFFFFFFFF))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700979 flags |= RTF_HOST;
980 flags |= RTF_UP;
981 return flags;
982}
983
984/*
985 * This outputs /proc/net/route.
986 *
987 * It always works in backward compatibility mode.
988 * The format of the file is not supposed to be changed.
989 */
990static int fib_seq_show(struct seq_file *seq, void *v)
991{
992 struct fib_iter_state *iter;
993 char bf[128];
Al Virob6e80c62006-09-26 22:20:01 -0700994 __be32 prefix, mask;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700995 unsigned flags;
996 struct fib_node *f;
997 struct fib_alias *fa;
998 struct fib_info *fi;
999
1000 if (v == SEQ_START_TOKEN) {
1001 seq_printf(seq, "%-127s\n", "Iface\tDestination\tGateway "
1002 "\tFlags\tRefCnt\tUse\tMetric\tMask\t\tMTU"
1003 "\tWindow\tIRTT");
1004 goto out;
1005 }
1006
1007 iter = seq->private;
1008 f = iter->fn;
1009 fa = iter->fa;
1010 fi = fa->fa_info;
1011 prefix = f->fn_key;
1012 mask = FZ_MASK(iter->zone);
1013 flags = fib_flag_trans(fa->fa_type, mask, fi);
1014 if (fi)
1015 snprintf(bf, sizeof(bf),
1016 "%s\t%08X\t%08X\t%04X\t%d\t%u\t%d\t%08X\t%d\t%u\t%u",
1017 fi->fib_dev ? fi->fib_dev->name : "*", prefix,
1018 fi->fib_nh->nh_gw, flags, 0, 0, fi->fib_priority,
1019 mask, (fi->fib_advmss ? fi->fib_advmss + 40 : 0),
1020 fi->fib_window,
1021 fi->fib_rtt >> 3);
1022 else
1023 snprintf(bf, sizeof(bf),
1024 "*\t%08X\t%08X\t%04X\t%d\t%u\t%d\t%08X\t%d\t%u\t%u",
1025 prefix, 0, flags, 0, 0, 0, mask, 0, 0, 0);
1026 seq_printf(seq, "%-127s\n", bf);
1027out:
1028 return 0;
1029}
1030
1031static struct seq_operations fib_seq_ops = {
1032 .start = fib_seq_start,
1033 .next = fib_seq_next,
1034 .stop = fib_seq_stop,
1035 .show = fib_seq_show,
1036};
1037
1038static int fib_seq_open(struct inode *inode, struct file *file)
1039{
1040 struct seq_file *seq;
1041 int rc = -ENOMEM;
Panagiotis Issaris0da974f2006-07-21 14:51:30 -07001042 struct fib_iter_state *s = kzalloc(sizeof(*s), GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001043
1044 if (!s)
1045 goto out;
1046
1047 rc = seq_open(file, &fib_seq_ops);
1048 if (rc)
1049 goto out_kfree;
1050
1051 seq = file->private_data;
1052 seq->private = s;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001053out:
1054 return rc;
1055out_kfree:
1056 kfree(s);
1057 goto out;
1058}
1059
1060static struct file_operations fib_seq_fops = {
1061 .owner = THIS_MODULE,
1062 .open = fib_seq_open,
1063 .read = seq_read,
1064 .llseek = seq_lseek,
1065 .release = seq_release_private,
1066};
1067
1068int __init fib_proc_init(void)
1069{
1070 if (!proc_net_fops_create("route", S_IRUGO, &fib_seq_fops))
1071 return -ENOMEM;
1072 return 0;
1073}
1074
1075void __init fib_proc_exit(void)
1076{
1077 proc_net_remove("route");
1078}
1079#endif /* CONFIG_PROC_FS */