1 /*
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
18 #include <linux/config.h>
19 #include <asm/uaccess.h>
20 #include <asm/system.h>
21 #include <linux/bitops.h>
22 #include <linux/types.h>
23 #include <linux/kernel.h>
24 #include <linux/sched.h>
25 #include <linux/mm.h>
26 #include <linux/string.h>
27 #include <linux/socket.h>
28 #include <linux/sockios.h>
29 #include <linux/errno.h>
30 #include <linux/in.h>
31 #include <linux/inet.h>
32 #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
48 static kmem_cache_t *fn_hash_kmem;
49 static kmem_cache_t *fn_alias_kmem;
50
51 struct fib_node {
52 struct hlist_node fn_hash;
53 struct list_head fn_alias;
54 u32 fn_key;
55 };
56
57 struct 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 */
67 u32 fz_mask;
68 #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
75 struct fn_hash {
76 struct fn_zone *fn_zones[33];
77 struct fn_zone *fn_zone_list;
78 };
79
80 static inline u32 fn_hash(u32 key, struct fn_zone *fz)
81 {
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
90 static inline u32 fz_key(u32 dst, struct fn_zone *fz)
91 {
92 return dst & FZ_MASK(fz);
93 }
94
95 static DEFINE_RWLOCK(fib_hash_lock);
96
97 #define FZ_MAX_DIVISOR ((PAGE_SIZE<<MAX_ORDER) / sizeof(struct hlist_head))
98
99 static struct hlist_head *fz_hash_alloc(int divisor)
100 {
101 unsigned long size = divisor * sizeof(struct hlist_head);
102
103 if (size <= PAGE_SIZE) {
104 return kmalloc(size, GFP_KERNEL);
105 } else {
106 return (struct hlist_head *)
107 __get_free_pages(GFP_KERNEL, get_order(size));
108 }
109 }
110
111 /* The fib hash lock must be held when this is called. */
112 static inline void fn_rebuild_zone(struct fn_zone *fz,
113 struct hlist_head *old_ht,
114 int old_divisor)
115 {
116 int i;
117
118 for (i = 0; i < old_divisor; i++) {
119 struct hlist_node *node, *n;
120 struct fib_node *f;
121
122 hlist_for_each_entry_safe(f, node, n, &old_ht[i], fn_hash) {
123 struct hlist_head *new_head;
124
125 hlist_del(&f->fn_hash);
126
127 new_head = &fz->fz_hash[fn_hash(f->fn_key, fz)];
128 hlist_add_head(&f->fn_hash, new_head);
129 }
130 }
131 }
132
133 static void fz_hash_free(struct hlist_head *hash, int divisor)
134 {
135 unsigned long size = divisor * sizeof(struct hlist_head);
136
137 if (size <= PAGE_SIZE)
138 kfree(hash);
139 else
140 free_pages((unsigned long)hash, get_order(size));
141 }
142
143 static void fn_rehash_zone(struct fn_zone *fz)
144 {
145 struct hlist_head *ht, *old_ht;
146 int old_divisor, new_divisor;
147 u32 new_hashmask;
148
149 old_divisor = fz->fz_divisor;
150
151 switch (old_divisor) {
152 case 16:
153 new_divisor = 256;
154 break;
155 case 256:
156 new_divisor = 1024;
157 break;
158 default:
159 if ((old_divisor << 1) > FZ_MAX_DIVISOR) {
160 printk(KERN_CRIT "route.c: bad divisor %d!\n", old_divisor);
161 return;
162 }
163 new_divisor = (old_divisor << 1);
164 break;
165 }
166
167 new_hashmask = (new_divisor - 1);
168
169 #if RT_CACHE_DEBUG >= 2
170 printk("fn_rehash_zone: hash for zone %d grows from %d\n", fz->fz_order, old_divisor);
171 #endif
172
173 ht = fz_hash_alloc(new_divisor);
174
175 if (ht) {
176 memset(ht, 0, new_divisor * sizeof(struct hlist_head));
177
178 write_lock_bh(&fib_hash_lock);
179 old_ht = fz->fz_hash;
180 fz->fz_hash = ht;
181 fz->fz_hashmask = new_hashmask;
182 fz->fz_divisor = new_divisor;
183 fn_rebuild_zone(fz, old_ht, old_divisor);
184 write_unlock_bh(&fib_hash_lock);
185
186 fz_hash_free(old_ht, old_divisor);
187 }
188 }
189
190 static inline void fn_free_node(struct fib_node * f)
191 {
192 kmem_cache_free(fn_hash_kmem, f);
193 }
194
195 static inline void fn_free_alias(struct fib_alias *fa)
196 {
197 fib_release_info(fa->fa_info);
198 kmem_cache_free(fn_alias_kmem, fa);
199 }
200
201 static struct fn_zone *
202 fn_new_zone(struct fn_hash *table, int z)
203 {
204 int i;
205 struct fn_zone *fz = kmalloc(sizeof(struct fn_zone), GFP_KERNEL);
206 if (!fz)
207 return NULL;
208
209 memset(fz, 0, sizeof(struct fn_zone));
210 if (z) {
211 fz->fz_divisor = 16;
212 } else {
213 fz->fz_divisor = 1;
214 }
215 fz->fz_hashmask = (fz->fz_divisor - 1);
216 fz->fz_hash = fz_hash_alloc(fz->fz_divisor);
217 if (!fz->fz_hash) {
218 kfree(fz);
219 return NULL;
220 }
221 memset(fz->fz_hash, 0, fz->fz_divisor * sizeof(struct hlist_head *));
222 fz->fz_order = z;
223 fz->fz_mask = inet_make_mask(z);
224
225 /* Find the first not empty zone with more specific mask */
226 for (i=z+1; i<=32; i++)
227 if (table->fn_zones[i])
228 break;
229 write_lock_bh(&fib_hash_lock);
230 if (i>32) {
231 /* No more specific masks, we are the first. */
232 fz->fz_next = table->fn_zone_list;
233 table->fn_zone_list = fz;
234 } else {
235 fz->fz_next = table->fn_zones[i]->fz_next;
236 table->fn_zones[i]->fz_next = fz;
237 }
238 table->fn_zones[z] = fz;
239 write_unlock_bh(&fib_hash_lock);
240 return fz;
241 }
242
243 static int
244 fn_hash_lookup(struct fib_table *tb, const struct flowi *flp, struct fib_result *res)
245 {
246 int err;
247 struct fn_zone *fz;
248 struct fn_hash *t = (struct fn_hash*)tb->tb_data;
249
250 read_lock(&fib_hash_lock);
251 for (fz = t->fn_zone_list; fz; fz = fz->fz_next) {
252 struct hlist_head *head;
253 struct hlist_node *node;
254 struct fib_node *f;
255 u32 k = fz_key(flp->fl4_dst, fz);
256
257 head = &fz->fz_hash[fn_hash(k, fz)];
258 hlist_for_each_entry(f, node, head, fn_hash) {
259 if (f->fn_key != k)
260 continue;
261
262 err = fib_semantic_match(&f->fn_alias,
263 flp, res,
264 fz->fz_order);
265 if (err <= 0)
266 goto out;
267 }
268 }
269 err = 1;
270 out:
271 read_unlock(&fib_hash_lock);
272 return err;
273 }
274
275 static int fn_hash_last_dflt=-1;
276
277 static void
278 fn_hash_select_default(struct fib_table *tb, const struct flowi *flp, struct fib_result *res)
279 {
280 int order, last_idx;
281 struct hlist_node *node;
282 struct fib_node *f;
283 struct fib_info *fi = NULL;
284 struct fib_info *last_resort;
285 struct fn_hash *t = (struct fn_hash*)tb->tb_data;
286 struct fn_zone *fz = t->fn_zones[0];
287
288 if (fz == NULL)
289 return;
290
291 last_idx = -1;
292 last_resort = NULL;
293 order = -1;
294
295 read_lock(&fib_hash_lock);
296 hlist_for_each_entry(f, node, &fz->fz_hash[0], fn_hash) {
297 struct fib_alias *fa;
298
299 list_for_each_entry(fa, &f->fn_alias, fa_list) {
300 struct fib_info *next_fi = fa->fa_info;
301
302 if (fa->fa_scope != res->scope ||
303 fa->fa_type != RTN_UNICAST)
304 continue;
305
306 if (next_fi->fib_priority > res->fi->fib_priority)
307 break;
308 if (!next_fi->fib_nh[0].nh_gw ||
309 next_fi->fib_nh[0].nh_scope != RT_SCOPE_LINK)
310 continue;
311 fa->fa_state |= FA_S_ACCESSED;
312
313 if (fi == NULL) {
314 if (next_fi != res->fi)
315 break;
316 } else if (!fib_detect_death(fi, order, &last_resort,
317 &last_idx, &fn_hash_last_dflt)) {
318 if (res->fi)
319 fib_info_put(res->fi);
320 res->fi = fi;
321 atomic_inc(&fi->fib_clntref);
322 fn_hash_last_dflt = order;
323 goto out;
324 }
325 fi = next_fi;
326 order++;
327 }
328 }
329
330 if (order <= 0 || fi == NULL) {
331 fn_hash_last_dflt = -1;
332 goto out;
333 }
334
335 if (!fib_detect_death(fi, order, &last_resort, &last_idx, &fn_hash_last_dflt)) {
336 if (res->fi)
337 fib_info_put(res->fi);
338 res->fi = fi;
339 atomic_inc(&fi->fib_clntref);
340 fn_hash_last_dflt = order;
341 goto out;
342 }
343
344 if (last_idx >= 0) {
345 if (res->fi)
346 fib_info_put(res->fi);
347 res->fi = last_resort;
348 if (last_resort)
349 atomic_inc(&last_resort->fib_clntref);
350 }
351 fn_hash_last_dflt = last_idx;
352 out:
353 read_unlock(&fib_hash_lock);
354 }
355
356 /* Insert node F to FZ. */
357 static inline void fib_insert_node(struct fn_zone *fz, struct fib_node *f)
358 {
359 struct hlist_head *head = &fz->fz_hash[fn_hash(f->fn_key, fz)];
360
361 hlist_add_head(&f->fn_hash, head);
362 }
363
364 /* Return the node in FZ matching KEY. */
365 static struct fib_node *fib_find_node(struct fn_zone *fz, u32 key)
366 {
367 struct hlist_head *head = &fz->fz_hash[fn_hash(key, fz)];
368 struct hlist_node *node;
369 struct fib_node *f;
370
371 hlist_for_each_entry(f, node, head, fn_hash) {
372 if (f->fn_key == key)
373 return f;
374 }
375
376 return NULL;
377 }
378
379 static int
380 fn_hash_insert(struct fib_table *tb, struct rtmsg *r, struct kern_rta *rta,
381 struct nlmsghdr *n, struct netlink_skb_parms *req)
382 {
383 struct fn_hash *table = (struct fn_hash *) tb->tb_data;
384 struct fib_node *new_f, *f;
385 struct fib_alias *fa, *new_fa;
386 struct fn_zone *fz;
387 struct fib_info *fi;
388 int z = r->rtm_dst_len;
389 int type = r->rtm_type;
390 u8 tos = r->rtm_tos;
391 u32 key;
392 int err;
393
394 if (z > 32)
395 return -EINVAL;
396 fz = table->fn_zones[z];
397 if (!fz && !(fz = fn_new_zone(table, z)))
398 return -ENOBUFS;
399
400 key = 0;
401 if (rta->rta_dst) {
402 u32 dst;
403 memcpy(&dst, rta->rta_dst, 4);
404 if (dst & ~FZ_MASK(fz))
405 return -EINVAL;
406 key = fz_key(dst, fz);
407 }
408
409 if ((fi = fib_create_info(r, rta, n, &err)) == NULL)
410 return err;
411
412 if (fz->fz_nent > (fz->fz_divisor<<1) &&
413 fz->fz_divisor < FZ_MAX_DIVISOR &&
414 (z==32 || (1<<z) > fz->fz_divisor))
415 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;
440 if (n->nlmsg_flags & NLM_F_EXCL)
441 goto out;
442
443 if (n->nlmsg_flags & NLM_F_REPLACE) {
444 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;
450 fa->fa_type = type;
451 fa->fa_scope = r->rtm_scope;
452 state = fa->fa_state;
453 fa->fa_state &= ~FA_S_ACCESSED;
454 write_unlock_bh(&fib_hash_lock);
455
456 fib_release_info(fi_drop);
457 if (state & FA_S_ACCESSED)
458 rt_cache_flush(-1);
459 return 0;
460 }
461
462 /* Error if we find a perfect match which
463 * uses the same scope, type, and nexthop
464 * information.
465 */
466 fa_orig = fa;
467 fa = list_entry(fa->fa_list.prev, struct fib_alias, fa_list);
468 list_for_each_entry_continue(fa, &f->fn_alias, fa_list) {
469 if (fa->fa_tos != tos)
470 break;
471 if (fa->fa_info->fib_priority != fi->fib_priority)
472 break;
473 if (fa->fa_type == type &&
474 fa->fa_scope == r->rtm_scope &&
475 fa->fa_info == fi)
476 goto out;
477 }
478 if (!(n->nlmsg_flags & NLM_F_APPEND))
479 fa = fa_orig;
480 }
481
482 err = -ENOENT;
483 if (!(n->nlmsg_flags&NLM_F_CREATE))
484 goto out;
485
486 err = -ENOBUFS;
487 new_fa = kmem_cache_alloc(fn_alias_kmem, SLAB_KERNEL);
488 if (new_fa == NULL)
489 goto out;
490
491 new_f = NULL;
492 if (!f) {
493 new_f = kmem_cache_alloc(fn_hash_kmem, SLAB_KERNEL);
494 if (new_f == NULL)
495 goto out_free_new_fa;
496
497 INIT_HLIST_NODE(&new_f->fn_hash);
498 INIT_LIST_HEAD(&new_f->fn_alias);
499 new_f->fn_key = key;
500 f = new_f;
501 }
502
503 new_fa->fa_info = fi;
504 new_fa->fa_tos = tos;
505 new_fa->fa_type = type;
506 new_fa->fa_scope = r->rtm_scope;
507 new_fa->fa_state = 0;
508
509 /*
510 * Insert new entry to the list.
511 */
512
513 write_lock_bh(&fib_hash_lock);
514 if (new_f)
515 fib_insert_node(fz, new_f);
516 list_add_tail(&new_fa->fa_list,
517 (fa ? &fa->fa_list : &f->fn_alias));
518 write_unlock_bh(&fib_hash_lock);
519
520 if (new_f)
521 fz->fz_nent++;
522 rt_cache_flush(-1);
523
524 rtmsg_fib(RTM_NEWROUTE, key, new_fa, z, tb->tb_id, n, req);
525 return 0;
526
527 out_free_new_fa:
528 kmem_cache_free(fn_alias_kmem, new_fa);
529 out:
530 fib_release_info(fi);
531 return err;
532 }
533
534
535 static int
536 fn_hash_delete(struct fib_table *tb, struct rtmsg *r, struct kern_rta *rta,
537 struct nlmsghdr *n, struct netlink_skb_parms *req)
538 {
539 struct fn_hash *table = (struct fn_hash*)tb->tb_data;
540 struct fib_node *f;
541 struct fib_alias *fa, *fa_to_delete;
542 int z = r->rtm_dst_len;
543 struct fn_zone *fz;
544 u32 key;
545 u8 tos = r->rtm_tos;
546
547 if (z > 32)
548 return -EINVAL;
549 if ((fz = table->fn_zones[z]) == NULL)
550 return -ESRCH;
551
552 key = 0;
553 if (rta->rta_dst) {
554 u32 dst;
555 memcpy(&dst, rta->rta_dst, 4);
556 if (dst & ~FZ_MASK(fz))
557 return -EINVAL;
558 key = fz_key(dst, fz);
559 }
560
561 f = fib_find_node(fz, key);
562
563 if (!f)
564 fa = NULL;
565 else
566 fa = fib_find_alias(&f->fn_alias, tos, 0);
567 if (!fa)
568 return -ESRCH;
569
570 fa_to_delete = NULL;
571 fa = list_entry(fa->fa_list.prev, struct fib_alias, fa_list);
572 list_for_each_entry_continue(fa, &f->fn_alias, fa_list) {
573 struct fib_info *fi = fa->fa_info;
574
575 if (fa->fa_tos != tos)
576 break;
577
578 if ((!r->rtm_type ||
579 fa->fa_type == r->rtm_type) &&
580 (r->rtm_scope == RT_SCOPE_NOWHERE ||
581 fa->fa_scope == r->rtm_scope) &&
582 (!r->rtm_protocol ||
583 fi->fib_protocol == r->rtm_protocol) &&
584 fib_nh_match(r, n, rta, fi) == 0) {
585 fa_to_delete = fa;
586 break;
587 }
588 }
589
590 if (fa_to_delete) {
591 int kill_fn;
592
593 fa = fa_to_delete;
594 rtmsg_fib(RTM_DELROUTE, key, fa, z, tb->tb_id, n, req);
595
596 kill_fn = 0;
597 write_lock_bh(&fib_hash_lock);
598 list_del(&fa->fa_list);
599 if (list_empty(&f->fn_alias)) {
600 hlist_del(&f->fn_hash);
601 kill_fn = 1;
602 }
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
618 static 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 write_unlock_bh(&fib_hash_lock);
641
642 fn_free_alias(fa);
643 found++;
644 }
645 }
646 if (kill_f) {
647 fn_free_node(f);
648 fz->fz_nent--;
649 }
650 }
651 return found;
652 }
653
654 static int fn_hash_flush(struct fib_table *tb)
655 {
656 struct fn_hash *table = (struct fn_hash *) tb->tb_data;
657 struct fn_zone *fz;
658 int found = 0;
659
660 for (fz = table->fn_zone_list; fz; fz = fz->fz_next) {
661 int i;
662
663 for (i = fz->fz_divisor - 1; i >= 0; i--)
664 found += fn_flush_list(fz, i);
665 }
666 return found;
667 }
668
669
670 static inline int
671 fn_hash_dump_bucket(struct sk_buff *skb, struct netlink_callback *cb,
672 struct fib_table *tb,
673 struct fn_zone *fz,
674 struct hlist_head *head)
675 {
676 struct hlist_node *node;
677 struct fib_node *f;
678 int i, s_i;
679
680 s_i = cb->args[3];
681 i = 0;
682 hlist_for_each_entry(f, node, head, fn_hash) {
683 struct fib_alias *fa;
684
685 list_for_each_entry(fa, &f->fn_alias, fa_list) {
686 if (i < s_i)
687 goto next;
688
689 if (fib_dump_info(skb, NETLINK_CB(cb->skb).pid,
690 cb->nlh->nlmsg_seq,
691 RTM_NEWROUTE,
692 tb->tb_id,
693 fa->fa_type,
694 fa->fa_scope,
695 &f->fn_key,
696 fz->fz_order,
697 fa->fa_tos,
698 fa->fa_info) < 0) {
699 cb->args[3] = i;
700 return -1;
701 }
702 next:
703 i++;
704 }
705 }
706 cb->args[3] = i;
707 return skb->len;
708 }
709
710 static inline int
711 fn_hash_dump_zone(struct sk_buff *skb, struct netlink_callback *cb,
712 struct fib_table *tb,
713 struct fn_zone *fz)
714 {
715 int h, s_h;
716
717 s_h = cb->args[2];
718 for (h=0; h < fz->fz_divisor; h++) {
719 if (h < s_h) continue;
720 if (h > s_h)
721 memset(&cb->args[3], 0,
722 sizeof(cb->args) - 3*sizeof(cb->args[0]));
723 if (fz->fz_hash == NULL ||
724 hlist_empty(&fz->fz_hash[h]))
725 continue;
726 if (fn_hash_dump_bucket(skb, cb, tb, fz, &fz->fz_hash[h])<0) {
727 cb->args[2] = h;
728 return -1;
729 }
730 }
731 cb->args[2] = h;
732 return skb->len;
733 }
734
735 static int fn_hash_dump(struct fib_table *tb, struct sk_buff *skb, struct netlink_callback *cb)
736 {
737 int m, s_m;
738 struct fn_zone *fz;
739 struct fn_hash *table = (struct fn_hash*)tb->tb_data;
740
741 s_m = cb->args[1];
742 read_lock(&fib_hash_lock);
743 for (fz = table->fn_zone_list, m=0; fz; fz = fz->fz_next, m++) {
744 if (m < s_m) continue;
745 if (m > s_m)
746 memset(&cb->args[2], 0,
747 sizeof(cb->args) - 2*sizeof(cb->args[0]));
748 if (fn_hash_dump_zone(skb, cb, tb, fz) < 0) {
749 cb->args[1] = m;
750 read_unlock(&fib_hash_lock);
751 return -1;
752 }
753 }
754 read_unlock(&fib_hash_lock);
755 cb->args[1] = m;
756 return skb->len;
757 }
758
759 #ifdef CONFIG_IP_MULTIPLE_TABLES
760 struct fib_table * fib_hash_init(int id)
761 #else
762 struct fib_table * __init fib_hash_init(int id)
763 #endif
764 {
765 struct fib_table *tb;
766
767 if (fn_hash_kmem == NULL)
768 fn_hash_kmem = kmem_cache_create("ip_fib_hash",
769 sizeof(struct fib_node),
770 0, SLAB_HWCACHE_ALIGN,
771 NULL, NULL);
772
773 if (fn_alias_kmem == NULL)
774 fn_alias_kmem = kmem_cache_create("ip_fib_alias",
775 sizeof(struct fib_alias),
776 0, SLAB_HWCACHE_ALIGN,
777 NULL, NULL);
778
779 tb = kmalloc(sizeof(struct fib_table) + sizeof(struct fn_hash),
780 GFP_KERNEL);
781 if (tb == NULL)
782 return NULL;
783
784 tb->tb_id = id;
785 tb->tb_lookup = fn_hash_lookup;
786 tb->tb_insert = fn_hash_insert;
787 tb->tb_delete = fn_hash_delete;
788 tb->tb_flush = fn_hash_flush;
789 tb->tb_select_default = fn_hash_select_default;
790 tb->tb_dump = fn_hash_dump;
791 memset(tb->tb_data, 0, sizeof(struct fn_hash));
792 return tb;
793 }
794
795 /* ------------------------------------------------------------------------ */
796 #ifdef CONFIG_PROC_FS
797
798 struct fib_iter_state {
799 struct fn_zone *zone;
800 int bucket;
801 struct hlist_head *hash_head;
802 struct fib_node *fn;
803 struct fib_alias *fa;
804 };
805
806 static struct fib_alias *fib_get_first(struct seq_file *seq)
807 {
808 struct fib_iter_state *iter = seq->private;
809 struct fn_hash *table = (struct fn_hash *) ip_fib_main_table->tb_data;
810
811 iter->bucket = 0;
812 iter->hash_head = NULL;
813 iter->fn = NULL;
814 iter->fa = NULL;
815
816 for (iter->zone = table->fn_zone_list; iter->zone;
817 iter->zone = iter->zone->fz_next) {
818 int maxslot;
819
820 if (!iter->zone->fz_nent)
821 continue;
822
823 iter->hash_head = iter->zone->fz_hash;
824 maxslot = iter->zone->fz_divisor;
825
826 for (iter->bucket = 0; iter->bucket < maxslot;
827 ++iter->bucket, ++iter->hash_head) {
828 struct hlist_node *node;
829 struct fib_node *fn;
830
831 hlist_for_each_entry(fn,node,iter->hash_head,fn_hash) {
832 struct fib_alias *fa;
833
834 list_for_each_entry(fa,&fn->fn_alias,fa_list) {
835 iter->fn = fn;
836 iter->fa = fa;
837 goto out;
838 }
839 }
840 }
841 }
842 out:
843 return iter->fa;
844 }
845
846 static struct fib_alias *fib_get_next(struct seq_file *seq)
847 {
848 struct fib_iter_state *iter = seq->private;
849 struct fib_node *fn;
850 struct fib_alias *fa;
851
852 /* Advance FA, if any. */
853 fn = iter->fn;
854 fa = iter->fa;
855 if (fa) {
856 BUG_ON(!fn);
857 list_for_each_entry_continue(fa, &fn->fn_alias, fa_list) {
858 iter->fa = fa;
859 goto out;
860 }
861 }
862
863 fa = iter->fa = NULL;
864
865 /* Advance FN. */
866 if (fn) {
867 struct hlist_node *node = &fn->fn_hash;
868 hlist_for_each_entry_continue(fn, node, fn_hash) {
869 iter->fn = fn;
870
871 list_for_each_entry(fa, &fn->fn_alias, fa_list) {
872 iter->fa = fa;
873 goto out;
874 }
875 }
876 }
877
878 fn = iter->fn = NULL;
879
880 /* Advance hash chain. */
881 if (!iter->zone)
882 goto out;
883
884 for (;;) {
885 struct hlist_node *node;
886 int maxslot;
887
888 maxslot = iter->zone->fz_divisor;
889
890 while (++iter->bucket < maxslot) {
891 iter->hash_head++;
892
893 hlist_for_each_entry(fn, node, iter->hash_head, fn_hash) {
894 list_for_each_entry(fa, &fn->fn_alias, fa_list) {
895 iter->fn = fn;
896 iter->fa = fa;
897 goto out;
898 }
899 }
900 }
901
902 iter->zone = iter->zone->fz_next;
903
904 if (!iter->zone)
905 goto out;
906
907 iter->bucket = 0;
908 iter->hash_head = iter->zone->fz_hash;
909
910 hlist_for_each_entry(fn, node, iter->hash_head, fn_hash) {
911 list_for_each_entry(fa, &fn->fn_alias, fa_list) {
912 iter->fn = fn;
913 iter->fa = fa;
914 goto out;
915 }
916 }
917 }
918 out:
919 return fa;
920 }
921
922 static struct fib_alias *fib_get_idx(struct seq_file *seq, loff_t pos)
923 {
924 struct fib_alias *fa = fib_get_first(seq);
925
926 if (fa)
927 while (pos && (fa = fib_get_next(seq)))
928 --pos;
929 return pos ? NULL : fa;
930 }
931
932 static void *fib_seq_start(struct seq_file *seq, loff_t *pos)
933 {
934 void *v = NULL;
935
936 read_lock(&fib_hash_lock);
937 if (ip_fib_main_table)
938 v = *pos ? fib_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
939 return v;
940 }
941
942 static void *fib_seq_next(struct seq_file *seq, void *v, loff_t *pos)
943 {
944 ++*pos;
945 return v == SEQ_START_TOKEN ? fib_get_first(seq) : fib_get_next(seq);
946 }
947
948 static void fib_seq_stop(struct seq_file *seq, void *v)
949 {
950 read_unlock(&fib_hash_lock);
951 }
952
953 static unsigned fib_flag_trans(int type, u32 mask, struct fib_info *fi)
954 {
955 static unsigned type2flags[RTN_MAX + 1] = {
956 [7] = RTF_REJECT, [8] = RTF_REJECT,
957 };
958 unsigned flags = type2flags[type];
959
960 if (fi && fi->fib_nh->nh_gw)
961 flags |= RTF_GATEWAY;
962 if (mask == 0xFFFFFFFF)
963 flags |= RTF_HOST;
964 flags |= RTF_UP;
965 return flags;
966 }
967
968 /*
969 * This outputs /proc/net/route.
970 *
971 * It always works in backward compatibility mode.
972 * The format of the file is not supposed to be changed.
973 */
974 static int fib_seq_show(struct seq_file *seq, void *v)
975 {
976 struct fib_iter_state *iter;
977 char bf[128];
978 u32 prefix, mask;
979 unsigned flags;
980 struct fib_node *f;
981 struct fib_alias *fa;
982 struct fib_info *fi;
983
984 if (v == SEQ_START_TOKEN) {
985 seq_printf(seq, "%-127s\n", "Iface\tDestination\tGateway "
986 "\tFlags\tRefCnt\tUse\tMetric\tMask\t\tMTU"
987 "\tWindow\tIRTT");
988 goto out;
989 }
990
991 iter = seq->private;
992 f = iter->fn;
993 fa = iter->fa;
994 fi = fa->fa_info;
995 prefix = f->fn_key;
996 mask = FZ_MASK(iter->zone);
997 flags = fib_flag_trans(fa->fa_type, mask, fi);
998 if (fi)
999 snprintf(bf, sizeof(bf),
1000 "%s\t%08X\t%08X\t%04X\t%d\t%u\t%d\t%08X\t%d\t%u\t%u",
1001 fi->fib_dev ? fi->fib_dev->name : "*", prefix,
1002 fi->fib_nh->nh_gw, flags, 0, 0, fi->fib_priority,
1003 mask, (fi->fib_advmss ? fi->fib_advmss + 40 : 0),
1004 fi->fib_window,
1005 fi->fib_rtt >> 3);
1006 else
1007 snprintf(bf, sizeof(bf),
1008 "*\t%08X\t%08X\t%04X\t%d\t%u\t%d\t%08X\t%d\t%u\t%u",
1009 prefix, 0, flags, 0, 0, 0, mask, 0, 0, 0);
1010 seq_printf(seq, "%-127s\n", bf);
1011 out:
1012 return 0;
1013 }
1014
1015 static struct seq_operations fib_seq_ops = {
1016 .start = fib_seq_start,
1017 .next = fib_seq_next,
1018 .stop = fib_seq_stop,
1019 .show = fib_seq_show,
1020 };
1021
1022 static int fib_seq_open(struct inode *inode, struct file *file)
1023 {
1024 struct seq_file *seq;
1025 int rc = -ENOMEM;
1026 struct fib_iter_state *s = kmalloc(sizeof(*s), GFP_KERNEL);
1027
1028 if (!s)
1029 goto out;
1030
1031 rc = seq_open(file, &fib_seq_ops);
1032 if (rc)
1033 goto out_kfree;
1034
1035 seq = file->private_data;
1036 seq->private = s;
1037 memset(s, 0, sizeof(*s));
1038 out:
1039 return rc;
1040 out_kfree:
1041 kfree(s);
1042 goto out;
1043 }
1044
1045 static struct file_operations fib_seq_fops = {
1046 .owner = THIS_MODULE,
1047 .open = fib_seq_open,
1048 .read = seq_read,
1049 .llseek = seq_lseek,
1050 .release = seq_release_private,
1051 };
1052
1053 int __init fib_proc_init(void)
1054 {
1055 if (!proc_net_fops_create("route", S_IRUGO, &fib_seq_fops))
1056 return -ENOMEM;
1057 return 0;
1058 }
1059
1060 void __init fib_proc_exit(void)
1061 {
1062 proc_net_remove("route");
1063 }
1064 #endif /* CONFIG_PROC_FS */
1065
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