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1/*
2 * This program is free software; you can redistribute it and/or
3 * modify it under the terms of the GNU General Public License
4 * as published by the Free Software Foundation; either version
5 * 2 of the License, or (at your option) any later version.
6 *
7 * Robert Olsson <robert.olsson@its.uu.se> Uppsala Universitet
8 * & Swedish University of Agricultural Sciences.
9 *
10 * Jens Laas <jens.laas@data.slu.se> Swedish University of
11 * Agricultural Sciences.
12 *
13 * Hans Liss <hans.liss@its.uu.se> Uppsala Universitet
14 *
15 * This work is based on the LPC-trie which is originally described in:
16 *
17 * An experimental study of compression methods for dynamic tries
18 * Stefan Nilsson and Matti Tikkanen. Algorithmica, 33(1):19-33, 2002.
19 * http://www.csc.kth.se/~snilsson/software/dyntrie2/
20 *
21 *
22 * IP-address lookup using LC-tries. Stefan Nilsson and Gunnar Karlsson
23 * IEEE Journal on Selected Areas in Communications, 17(6):1083-1092, June 1999
24 *
25 *
26 * Code from fib_hash has been reused which includes the following header:
27 *
28 *
29 * INET An implementation of the TCP/IP protocol suite for the LINUX
30 * operating system. INET is implemented using the BSD Socket
31 * interface as the means of communication with the user level.
32 *
33 * IPv4 FIB: lookup engine and maintenance routines.
34 *
35 *
36 * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
37 *
38 * This program is free software; you can redistribute it and/or
39 * modify it under the terms of the GNU General Public License
40 * as published by the Free Software Foundation; either version
41 * 2 of the License, or (at your option) any later version.
42 *
43 * Substantial contributions to this work comes from:
44 *
45 * David S. Miller, <davem@davemloft.net>
46 * Stephen Hemminger <shemminger@osdl.org>
47 * Paul E. McKenney <paulmck@us.ibm.com>
48 * Patrick McHardy <kaber@trash.net>
49 */
50
51#define VERSION "0.409"
52
53#include <linux/cache.h>
54#include <linux/uaccess.h>
55#include <linux/bitops.h>
56#include <linux/types.h>
57#include <linux/kernel.h>
58#include <linux/mm.h>
59#include <linux/string.h>
60#include <linux/socket.h>
61#include <linux/sockios.h>
62#include <linux/errno.h>
63#include <linux/in.h>
64#include <linux/inet.h>
65#include <linux/inetdevice.h>
66#include <linux/netdevice.h>
67#include <linux/if_arp.h>
68#include <linux/proc_fs.h>
69#include <linux/rcupdate.h>
70#include <linux/skbuff.h>
71#include <linux/netlink.h>
72#include <linux/init.h>
73#include <linux/list.h>
74#include <linux/slab.h>
75#include <linux/export.h>
76#include <linux/vmalloc.h>
77#include <linux/notifier.h>
78#include <net/net_namespace.h>
79#include <net/ip.h>
80#include <net/protocol.h>
81#include <net/route.h>
82#include <net/tcp.h>
83#include <net/sock.h>
84#include <net/ip_fib.h>
85#include <net/fib_notifier.h>
86#include <trace/events/fib.h>
87#include "fib_lookup.h"
88
89static int call_fib_entry_notifier(struct notifier_block *nb, struct net *net,
90 enum fib_event_type event_type, u32 dst,
91 int dst_len, struct fib_alias *fa)
92{
93 struct fib_entry_notifier_info info = {
94 .dst = dst,
95 .dst_len = dst_len,
96 .fi = fa->fa_info,
97 .tos = fa->fa_tos,
98 .type = fa->fa_type,
99 .tb_id = fa->tb_id,
100 };
101 return call_fib4_notifier(nb, net, event_type, &info.info);
102}
103
104static int call_fib_entry_notifiers(struct net *net,
105 enum fib_event_type event_type, u32 dst,
106 int dst_len, struct fib_alias *fa,
107 struct netlink_ext_ack *extack)
108{
109 struct fib_entry_notifier_info info = {
110 .info.extack = extack,
111 .dst = dst,
112 .dst_len = dst_len,
113 .fi = fa->fa_info,
114 .tos = fa->fa_tos,
115 .type = fa->fa_type,
116 .tb_id = fa->tb_id,
117 };
118 return call_fib4_notifiers(net, event_type, &info.info);
119}
120
121#define MAX_STAT_DEPTH 32
122
123#define KEYLENGTH (8*sizeof(t_key))
124#define KEY_MAX ((t_key)~0)
125
126typedef unsigned int t_key;
127
128#define IS_TRIE(n) ((n)->pos >= KEYLENGTH)
129#define IS_TNODE(n) ((n)->bits)
130#define IS_LEAF(n) (!(n)->bits)
131
132struct key_vector {
133 t_key key;
134 unsigned char pos; /* 2log(KEYLENGTH) bits needed */
135 unsigned char bits; /* 2log(KEYLENGTH) bits needed */
136 unsigned char slen;
137 union {
138 /* This list pointer if valid if (pos | bits) == 0 (LEAF) */
139 struct hlist_head leaf;
140 /* This array is valid if (pos | bits) > 0 (TNODE) */
141 struct key_vector __rcu *tnode[0];
142 };
143};
144
145struct tnode {
146 struct rcu_head rcu;
147 t_key empty_children; /* KEYLENGTH bits needed */
148 t_key full_children; /* KEYLENGTH bits needed */
149 struct key_vector __rcu *parent;
150 struct key_vector kv[1];
151#define tn_bits kv[0].bits
152};
153
154#define TNODE_SIZE(n) offsetof(struct tnode, kv[0].tnode[n])
155#define LEAF_SIZE TNODE_SIZE(1)
156
157#ifdef CONFIG_IP_FIB_TRIE_STATS
158struct trie_use_stats {
159 unsigned int gets;
160 unsigned int backtrack;
161 unsigned int semantic_match_passed;
162 unsigned int semantic_match_miss;
163 unsigned int null_node_hit;
164 unsigned int resize_node_skipped;
165};
166#endif
167
168struct trie_stat {
169 unsigned int totdepth;
170 unsigned int maxdepth;
171 unsigned int tnodes;
172 unsigned int leaves;
173 unsigned int nullpointers;
174 unsigned int prefixes;
175 unsigned int nodesizes[MAX_STAT_DEPTH];
176};
177
178struct trie {
179 struct key_vector kv[1];
180#ifdef CONFIG_IP_FIB_TRIE_STATS
181 struct trie_use_stats __percpu *stats;
182#endif
183};
184
185static struct key_vector *resize(struct trie *t, struct key_vector *tn);
186static size_t tnode_free_size;
187
188/*
189 * synchronize_rcu after call_rcu for that many pages; it should be especially
190 * useful before resizing the root node with PREEMPT_NONE configs; the value was
191 * obtained experimentally, aiming to avoid visible slowdown.
192 */
193static const int sync_pages = 128;
194
195static struct kmem_cache *fn_alias_kmem __ro_after_init;
196static struct kmem_cache *trie_leaf_kmem __ro_after_init;
197
198static inline struct tnode *tn_info(struct key_vector *kv)
199{
200 return container_of(kv, struct tnode, kv[0]);
201}
202
203/* caller must hold RTNL */
204#define node_parent(tn) rtnl_dereference(tn_info(tn)->parent)
205#define get_child(tn, i) rtnl_dereference((tn)->tnode[i])
206
207/* caller must hold RCU read lock or RTNL */
208#define node_parent_rcu(tn) rcu_dereference_rtnl(tn_info(tn)->parent)
209#define get_child_rcu(tn, i) rcu_dereference_rtnl((tn)->tnode[i])
210
211/* wrapper for rcu_assign_pointer */
212static inline void node_set_parent(struct key_vector *n, struct key_vector *tp)
213{
214 if (n)
215 rcu_assign_pointer(tn_info(n)->parent, tp);
216}
217
218#define NODE_INIT_PARENT(n, p) RCU_INIT_POINTER(tn_info(n)->parent, p)
219
220/* This provides us with the number of children in this node, in the case of a
221 * leaf this will return 0 meaning none of the children are accessible.
222 */
223static inline unsigned long child_length(const struct key_vector *tn)
224{
225 return (1ul << tn->bits) & ~(1ul);
226}
227
228#define get_cindex(key, kv) (((key) ^ (kv)->key) >> (kv)->pos)
229
230static inline unsigned long get_index(t_key key, struct key_vector *kv)
231{
232 unsigned long index = key ^ kv->key;
233
234 if ((BITS_PER_LONG <= KEYLENGTH) && (KEYLENGTH == kv->pos))
235 return 0;
236
237 return index >> kv->pos;
238}
239
240/* To understand this stuff, an understanding of keys and all their bits is
241 * necessary. Every node in the trie has a key associated with it, but not
242 * all of the bits in that key are significant.
243 *
244 * Consider a node 'n' and its parent 'tp'.
245 *
246 * If n is a leaf, every bit in its key is significant. Its presence is
247 * necessitated by path compression, since during a tree traversal (when
248 * searching for a leaf - unless we are doing an insertion) we will completely
249 * ignore all skipped bits we encounter. Thus we need to verify, at the end of
250 * a potentially successful search, that we have indeed been walking the
251 * correct key path.
252 *
253 * Note that we can never "miss" the correct key in the tree if present by
254 * following the wrong path. Path compression ensures that segments of the key
255 * that are the same for all keys with a given prefix are skipped, but the
256 * skipped part *is* identical for each node in the subtrie below the skipped
257 * bit! trie_insert() in this implementation takes care of that.
258 *
259 * if n is an internal node - a 'tnode' here, the various parts of its key
260 * have many different meanings.
261 *
262 * Example:
263 * _________________________________________________________________
264 * | i | i | i | i | i | i | i | N | N | N | S | S | S | S | S | C |
265 * -----------------------------------------------------------------
266 * 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16
267 *
268 * _________________________________________________________________
269 * | C | C | C | u | u | u | u | u | u | u | u | u | u | u | u | u |
270 * -----------------------------------------------------------------
271 * 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
272 *
273 * tp->pos = 22
274 * tp->bits = 3
275 * n->pos = 13
276 * n->bits = 4
277 *
278 * First, let's just ignore the bits that come before the parent tp, that is
279 * the bits from (tp->pos + tp->bits) to 31. They are *known* but at this
280 * point we do not use them for anything.
281 *
282 * The bits from (tp->pos) to (tp->pos + tp->bits - 1) - "N", above - are the
283 * index into the parent's child array. That is, they will be used to find
284 * 'n' among tp's children.
285 *
286 * The bits from (n->pos + n->bits) to (tp->pos - 1) - "S" - are skipped bits
287 * for the node n.
288 *
289 * All the bits we have seen so far are significant to the node n. The rest
290 * of the bits are really not needed or indeed known in n->key.
291 *
292 * The bits from (n->pos) to (n->pos + n->bits - 1) - "C" - are the index into
293 * n's child array, and will of course be different for each child.
294 *
295 * The rest of the bits, from 0 to (n->pos -1) - "u" - are completely unknown
296 * at this point.
297 */
298
299static const int halve_threshold = 25;
300static const int inflate_threshold = 50;
301static const int halve_threshold_root = 15;
302static const int inflate_threshold_root = 30;
303
304static void __alias_free_mem(struct rcu_head *head)
305{
306 struct fib_alias *fa = container_of(head, struct fib_alias, rcu);
307 kmem_cache_free(fn_alias_kmem, fa);
308}
309
310static inline void alias_free_mem_rcu(struct fib_alias *fa)
311{
312 call_rcu(&fa->rcu, __alias_free_mem);
313}
314
315#define TNODE_KMALLOC_MAX \
316 ilog2((PAGE_SIZE - TNODE_SIZE(0)) / sizeof(struct key_vector *))
317#define TNODE_VMALLOC_MAX \
318 ilog2((SIZE_MAX - TNODE_SIZE(0)) / sizeof(struct key_vector *))
319
320static void __node_free_rcu(struct rcu_head *head)
321{
322 struct tnode *n = container_of(head, struct tnode, rcu);
323
324 if (!n->tn_bits)
325 kmem_cache_free(trie_leaf_kmem, n);
326 else
327 kvfree(n);
328}
329
330#define node_free(n) call_rcu(&tn_info(n)->rcu, __node_free_rcu)
331
332static struct tnode *tnode_alloc(int bits)
333{
334 size_t size;
335
336 /* verify bits is within bounds */
337 if (bits > TNODE_VMALLOC_MAX)
338 return NULL;
339
340 /* determine size and verify it is non-zero and didn't overflow */
341 size = TNODE_SIZE(1ul << bits);
342
343 if (size <= PAGE_SIZE)
344 return kzalloc(size, GFP_KERNEL);
345 else
346 return vzalloc(size);
347}
348
349static inline void empty_child_inc(struct key_vector *n)
350{
351 ++tn_info(n)->empty_children ? : ++tn_info(n)->full_children;
352}
353
354static inline void empty_child_dec(struct key_vector *n)
355{
356 tn_info(n)->empty_children-- ? : tn_info(n)->full_children--;
357}
358
359static struct key_vector *leaf_new(t_key key, struct fib_alias *fa)
360{
361 struct key_vector *l;
362 struct tnode *kv;
363
364 kv = kmem_cache_alloc(trie_leaf_kmem, GFP_KERNEL);
365 if (!kv)
366 return NULL;
367
368 /* initialize key vector */
369 l = kv->kv;
370 l->key = key;
371 l->pos = 0;
372 l->bits = 0;
373 l->slen = fa->fa_slen;
374
375 /* link leaf to fib alias */
376 INIT_HLIST_HEAD(&l->leaf);
377 hlist_add_head(&fa->fa_list, &l->leaf);
378
379 return l;
380}
381
382static struct key_vector *tnode_new(t_key key, int pos, int bits)
383{
384 unsigned int shift = pos + bits;
385 struct key_vector *tn;
386 struct tnode *tnode;
387
388 /* verify bits and pos their msb bits clear and values are valid */
389 BUG_ON(!bits || (shift > KEYLENGTH));
390
391 tnode = tnode_alloc(bits);
392 if (!tnode)
393 return NULL;
394
395 pr_debug("AT %p s=%zu %zu\n", tnode, TNODE_SIZE(0),
396 sizeof(struct key_vector *) << bits);
397
398 if (bits == KEYLENGTH)
399 tnode->full_children = 1;
400 else
401 tnode->empty_children = 1ul << bits;
402
403 tn = tnode->kv;
404 tn->key = (shift < KEYLENGTH) ? (key >> shift) << shift : 0;
405 tn->pos = pos;
406 tn->bits = bits;
407 tn->slen = pos;
408
409 return tn;
410}
411
412/* Check whether a tnode 'n' is "full", i.e. it is an internal node
413 * and no bits are skipped. See discussion in dyntree paper p. 6
414 */
415static inline int tnode_full(struct key_vector *tn, struct key_vector *n)
416{
417 return n && ((n->pos + n->bits) == tn->pos) && IS_TNODE(n);
418}
419
420/* Add a child at position i overwriting the old value.
421 * Update the value of full_children and empty_children.
422 */
423static void put_child(struct key_vector *tn, unsigned long i,
424 struct key_vector *n)
425{
426 struct key_vector *chi = get_child(tn, i);
427 int isfull, wasfull;
428
429 BUG_ON(i >= child_length(tn));
430
431 /* update emptyChildren, overflow into fullChildren */
432 if (!n && chi)
433 empty_child_inc(tn);
434 if (n && !chi)
435 empty_child_dec(tn);
436
437 /* update fullChildren */
438 wasfull = tnode_full(tn, chi);
439 isfull = tnode_full(tn, n);
440
441 if (wasfull && !isfull)
442 tn_info(tn)->full_children--;
443 else if (!wasfull && isfull)
444 tn_info(tn)->full_children++;
445
446 if (n && (tn->slen < n->slen))
447 tn->slen = n->slen;
448
449 rcu_assign_pointer(tn->tnode[i], n);
450}
451
452static void update_children(struct key_vector *tn)
453{
454 unsigned long i;
455
456 /* update all of the child parent pointers */
457 for (i = child_length(tn); i;) {
458 struct key_vector *inode = get_child(tn, --i);
459
460 if (!inode)
461 continue;
462
463 /* Either update the children of a tnode that
464 * already belongs to us or update the child
465 * to point to ourselves.
466 */
467 if (node_parent(inode) == tn)
468 update_children(inode);
469 else
470 node_set_parent(inode, tn);
471 }
472}
473
474static inline void put_child_root(struct key_vector *tp, t_key key,
475 struct key_vector *n)
476{
477 if (IS_TRIE(tp))
478 rcu_assign_pointer(tp->tnode[0], n);
479 else
480 put_child(tp, get_index(key, tp), n);
481}
482
483static inline void tnode_free_init(struct key_vector *tn)
484{
485 tn_info(tn)->rcu.next = NULL;
486}
487
488static inline void tnode_free_append(struct key_vector *tn,
489 struct key_vector *n)
490{
491 tn_info(n)->rcu.next = tn_info(tn)->rcu.next;
492 tn_info(tn)->rcu.next = &tn_info(n)->rcu;
493}
494
495static void tnode_free(struct key_vector *tn)
496{
497 struct callback_head *head = &tn_info(tn)->rcu;
498
499 while (head) {
500 head = head->next;
501 tnode_free_size += TNODE_SIZE(1ul << tn->bits);
502 node_free(tn);
503
504 tn = container_of(head, struct tnode, rcu)->kv;
505 }
506
507 if (tnode_free_size >= PAGE_SIZE * sync_pages) {
508 tnode_free_size = 0;
509 synchronize_rcu();
510 }
511}
512
513static struct key_vector *replace(struct trie *t,
514 struct key_vector *oldtnode,
515 struct key_vector *tn)
516{
517 struct key_vector *tp = node_parent(oldtnode);
518 unsigned long i;
519
520 /* setup the parent pointer out of and back into this node */
521 NODE_INIT_PARENT(tn, tp);
522 put_child_root(tp, tn->key, tn);
523
524 /* update all of the child parent pointers */
525 update_children(tn);
526
527 /* all pointers should be clean so we are done */
528 tnode_free(oldtnode);
529
530 /* resize children now that oldtnode is freed */
531 for (i = child_length(tn); i;) {
532 struct key_vector *inode = get_child(tn, --i);
533
534 /* resize child node */
535 if (tnode_full(tn, inode))
536 tn = resize(t, inode);
537 }
538
539 return tp;
540}
541
542static struct key_vector *inflate(struct trie *t,
543 struct key_vector *oldtnode)
544{
545 struct key_vector *tn;
546 unsigned long i;
547 t_key m;
548
549 pr_debug("In inflate\n");
550
551 tn = tnode_new(oldtnode->key, oldtnode->pos - 1, oldtnode->bits + 1);
552 if (!tn)
553 goto notnode;
554
555 /* prepare oldtnode to be freed */
556 tnode_free_init(oldtnode);
557
558 /* Assemble all of the pointers in our cluster, in this case that
559 * represents all of the pointers out of our allocated nodes that
560 * point to existing tnodes and the links between our allocated
561 * nodes.
562 */
563 for (i = child_length(oldtnode), m = 1u << tn->pos; i;) {
564 struct key_vector *inode = get_child(oldtnode, --i);
565 struct key_vector *node0, *node1;
566 unsigned long j, k;
567
568 /* An empty child */
569 if (!inode)
570 continue;
571
572 /* A leaf or an internal node with skipped bits */
573 if (!tnode_full(oldtnode, inode)) {
574 put_child(tn, get_index(inode->key, tn), inode);
575 continue;
576 }
577
578 /* drop the node in the old tnode free list */
579 tnode_free_append(oldtnode, inode);
580
581 /* An internal node with two children */
582 if (inode->bits == 1) {
583 put_child(tn, 2 * i + 1, get_child(inode, 1));
584 put_child(tn, 2 * i, get_child(inode, 0));
585 continue;
586 }
587
588 /* We will replace this node 'inode' with two new
589 * ones, 'node0' and 'node1', each with half of the
590 * original children. The two new nodes will have
591 * a position one bit further down the key and this
592 * means that the "significant" part of their keys
593 * (see the discussion near the top of this file)
594 * will differ by one bit, which will be "0" in
595 * node0's key and "1" in node1's key. Since we are
596 * moving the key position by one step, the bit that
597 * we are moving away from - the bit at position
598 * (tn->pos) - is the one that will differ between
599 * node0 and node1. So... we synthesize that bit in the
600 * two new keys.
601 */
602 node1 = tnode_new(inode->key | m, inode->pos, inode->bits - 1);
603 if (!node1)
604 goto nomem;
605 node0 = tnode_new(inode->key, inode->pos, inode->bits - 1);
606
607 tnode_free_append(tn, node1);
608 if (!node0)
609 goto nomem;
610 tnode_free_append(tn, node0);
611
612 /* populate child pointers in new nodes */
613 for (k = child_length(inode), j = k / 2; j;) {
614 put_child(node1, --j, get_child(inode, --k));
615 put_child(node0, j, get_child(inode, j));
616 put_child(node1, --j, get_child(inode, --k));
617 put_child(node0, j, get_child(inode, j));
618 }
619
620 /* link new nodes to parent */
621 NODE_INIT_PARENT(node1, tn);
622 NODE_INIT_PARENT(node0, tn);
623
624 /* link parent to nodes */
625 put_child(tn, 2 * i + 1, node1);
626 put_child(tn, 2 * i, node0);
627 }
628
629 /* setup the parent pointers into and out of this node */
630 return replace(t, oldtnode, tn);
631nomem:
632 /* all pointers should be clean so we are done */
633 tnode_free(tn);
634notnode:
635 return NULL;
636}
637
638static struct key_vector *halve(struct trie *t,
639 struct key_vector *oldtnode)
640{
641 struct key_vector *tn;
642 unsigned long i;
643
644 pr_debug("In halve\n");
645
646 tn = tnode_new(oldtnode->key, oldtnode->pos + 1, oldtnode->bits - 1);
647 if (!tn)
648 goto notnode;
649
650 /* prepare oldtnode to be freed */
651 tnode_free_init(oldtnode);
652
653 /* Assemble all of the pointers in our cluster, in this case that
654 * represents all of the pointers out of our allocated nodes that
655 * point to existing tnodes and the links between our allocated
656 * nodes.
657 */
658 for (i = child_length(oldtnode); i;) {
659 struct key_vector *node1 = get_child(oldtnode, --i);
660 struct key_vector *node0 = get_child(oldtnode, --i);
661 struct key_vector *inode;
662
663 /* At least one of the children is empty */
664 if (!node1 || !node0) {
665 put_child(tn, i / 2, node1 ? : node0);
666 continue;
667 }
668
669 /* Two nonempty children */
670 inode = tnode_new(node0->key, oldtnode->pos, 1);
671 if (!inode)
672 goto nomem;
673 tnode_free_append(tn, inode);
674
675 /* initialize pointers out of node */
676 put_child(inode, 1, node1);
677 put_child(inode, 0, node0);
678 NODE_INIT_PARENT(inode, tn);
679
680 /* link parent to node */
681 put_child(tn, i / 2, inode);
682 }
683
684 /* setup the parent pointers into and out of this node */
685 return replace(t, oldtnode, tn);
686nomem:
687 /* all pointers should be clean so we are done */
688 tnode_free(tn);
689notnode:
690 return NULL;
691}
692
693static struct key_vector *collapse(struct trie *t,
694 struct key_vector *oldtnode)
695{
696 struct key_vector *n, *tp;
697 unsigned long i;
698
699 /* scan the tnode looking for that one child that might still exist */
700 for (n = NULL, i = child_length(oldtnode); !n && i;)
701 n = get_child(oldtnode, --i);
702
703 /* compress one level */
704 tp = node_parent(oldtnode);
705 put_child_root(tp, oldtnode->key, n);
706 node_set_parent(n, tp);
707
708 /* drop dead node */
709 node_free(oldtnode);
710
711 return tp;
712}
713
714static unsigned char update_suffix(struct key_vector *tn)
715{
716 unsigned char slen = tn->pos;
717 unsigned long stride, i;
718 unsigned char slen_max;
719
720 /* only vector 0 can have a suffix length greater than or equal to
721 * tn->pos + tn->bits, the second highest node will have a suffix
722 * length at most of tn->pos + tn->bits - 1
723 */
724 slen_max = min_t(unsigned char, tn->pos + tn->bits - 1, tn->slen);
725
726 /* search though the list of children looking for nodes that might
727 * have a suffix greater than the one we currently have. This is
728 * why we start with a stride of 2 since a stride of 1 would
729 * represent the nodes with suffix length equal to tn->pos
730 */
731 for (i = 0, stride = 0x2ul ; i < child_length(tn); i += stride) {
732 struct key_vector *n = get_child(tn, i);
733
734 if (!n || (n->slen <= slen))
735 continue;
736
737 /* update stride and slen based on new value */
738 stride <<= (n->slen - slen);
739 slen = n->slen;
740 i &= ~(stride - 1);
741
742 /* stop searching if we have hit the maximum possible value */
743 if (slen >= slen_max)
744 break;
745 }
746
747 tn->slen = slen;
748
749 return slen;
750}
751
752/* From "Implementing a dynamic compressed trie" by Stefan Nilsson of
753 * the Helsinki University of Technology and Matti Tikkanen of Nokia
754 * Telecommunications, page 6:
755 * "A node is doubled if the ratio of non-empty children to all
756 * children in the *doubled* node is at least 'high'."
757 *
758 * 'high' in this instance is the variable 'inflate_threshold'. It
759 * is expressed as a percentage, so we multiply it with
760 * child_length() and instead of multiplying by 2 (since the
761 * child array will be doubled by inflate()) and multiplying
762 * the left-hand side by 100 (to handle the percentage thing) we
763 * multiply the left-hand side by 50.
764 *
765 * The left-hand side may look a bit weird: child_length(tn)
766 * - tn->empty_children is of course the number of non-null children
767 * in the current node. tn->full_children is the number of "full"
768 * children, that is non-null tnodes with a skip value of 0.
769 * All of those will be doubled in the resulting inflated tnode, so
770 * we just count them one extra time here.
771 *
772 * A clearer way to write this would be:
773 *
774 * to_be_doubled = tn->full_children;
775 * not_to_be_doubled = child_length(tn) - tn->empty_children -
776 * tn->full_children;
777 *
778 * new_child_length = child_length(tn) * 2;
779 *
780 * new_fill_factor = 100 * (not_to_be_doubled + 2*to_be_doubled) /
781 * new_child_length;
782 * if (new_fill_factor >= inflate_threshold)
783 *
784 * ...and so on, tho it would mess up the while () loop.
785 *
786 * anyway,
787 * 100 * (not_to_be_doubled + 2*to_be_doubled) / new_child_length >=
788 * inflate_threshold
789 *
790 * avoid a division:
791 * 100 * (not_to_be_doubled + 2*to_be_doubled) >=
792 * inflate_threshold * new_child_length
793 *
794 * expand not_to_be_doubled and to_be_doubled, and shorten:
795 * 100 * (child_length(tn) - tn->empty_children +
796 * tn->full_children) >= inflate_threshold * new_child_length
797 *
798 * expand new_child_length:
799 * 100 * (child_length(tn) - tn->empty_children +
800 * tn->full_children) >=
801 * inflate_threshold * child_length(tn) * 2
802 *
803 * shorten again:
804 * 50 * (tn->full_children + child_length(tn) -
805 * tn->empty_children) >= inflate_threshold *
806 * child_length(tn)
807 *
808 */
809static inline bool should_inflate(struct key_vector *tp, struct key_vector *tn)
810{
811 unsigned long used = child_length(tn);
812 unsigned long threshold = used;
813
814 /* Keep root node larger */
815 threshold *= IS_TRIE(tp) ? inflate_threshold_root : inflate_threshold;
816 used -= tn_info(tn)->empty_children;
817 used += tn_info(tn)->full_children;
818
819 /* if bits == KEYLENGTH then pos = 0, and will fail below */
820
821 return (used > 1) && tn->pos && ((50 * used) >= threshold);
822}
823
824static inline bool should_halve(struct key_vector *tp, struct key_vector *tn)
825{
826 unsigned long used = child_length(tn);
827 unsigned long threshold = used;
828
829 /* Keep root node larger */
830 threshold *= IS_TRIE(tp) ? halve_threshold_root : halve_threshold;
831 used -= tn_info(tn)->empty_children;
832
833 /* if bits == KEYLENGTH then used = 100% on wrap, and will fail below */
834
835 return (used > 1) && (tn->bits > 1) && ((100 * used) < threshold);
836}
837
838static inline bool should_collapse(struct key_vector *tn)
839{
840 unsigned long used = child_length(tn);
841
842 used -= tn_info(tn)->empty_children;
843
844 /* account for bits == KEYLENGTH case */
845 if ((tn->bits == KEYLENGTH) && tn_info(tn)->full_children)
846 used -= KEY_MAX;
847
848 /* One child or none, time to drop us from the trie */
849 return used < 2;
850}
851
852#define MAX_WORK 10
853static struct key_vector *resize(struct trie *t, struct key_vector *tn)
854{
855#ifdef CONFIG_IP_FIB_TRIE_STATS
856 struct trie_use_stats __percpu *stats = t->stats;
857#endif
858 struct key_vector *tp = node_parent(tn);
859 unsigned long cindex = get_index(tn->key, tp);
860 int max_work = MAX_WORK;
861
862 pr_debug("In tnode_resize %p inflate_threshold=%d threshold=%d\n",
863 tn, inflate_threshold, halve_threshold);
864
865 /* track the tnode via the pointer from the parent instead of
866 * doing it ourselves. This way we can let RCU fully do its
867 * thing without us interfering
868 */
869 BUG_ON(tn != get_child(tp, cindex));
870
871 /* Double as long as the resulting node has a number of
872 * nonempty nodes that are above the threshold.
873 */
874 while (should_inflate(tp, tn) && max_work) {
875 tp = inflate(t, tn);
876 if (!tp) {
877#ifdef CONFIG_IP_FIB_TRIE_STATS
878 this_cpu_inc(stats->resize_node_skipped);
879#endif
880 break;
881 }
882
883 max_work--;
884 tn = get_child(tp, cindex);
885 }
886
887 /* update parent in case inflate failed */
888 tp = node_parent(tn);
889
890 /* Return if at least one inflate is run */
891 if (max_work != MAX_WORK)
892 return tp;
893
894 /* Halve as long as the number of empty children in this
895 * node is above threshold.
896 */
897 while (should_halve(tp, tn) && max_work) {
898 tp = halve(t, tn);
899 if (!tp) {
900#ifdef CONFIG_IP_FIB_TRIE_STATS
901 this_cpu_inc(stats->resize_node_skipped);
902#endif
903 break;
904 }
905
906 max_work--;
907 tn = get_child(tp, cindex);
908 }
909
910 /* Only one child remains */
911 if (should_collapse(tn))
912 return collapse(t, tn);
913
914 /* update parent in case halve failed */
915 return node_parent(tn);
916}
917
918static void node_pull_suffix(struct key_vector *tn, unsigned char slen)
919{
920 unsigned char node_slen = tn->slen;
921
922 while ((node_slen > tn->pos) && (node_slen > slen)) {
923 slen = update_suffix(tn);
924 if (node_slen == slen)
925 break;
926
927 tn = node_parent(tn);
928 node_slen = tn->slen;
929 }
930}
931
932static void node_push_suffix(struct key_vector *tn, unsigned char slen)
933{
934 while (tn->slen < slen) {
935 tn->slen = slen;
936 tn = node_parent(tn);
937 }
938}
939
940/* rcu_read_lock needs to be hold by caller from readside */
941static struct key_vector *fib_find_node(struct trie *t,
942 struct key_vector **tp, u32 key)
943{
944 struct key_vector *pn, *n = t->kv;
945 unsigned long index = 0;
946
947 do {
948 pn = n;
949 n = get_child_rcu(n, index);
950
951 if (!n)
952 break;
953
954 index = get_cindex(key, n);
955
956 /* This bit of code is a bit tricky but it combines multiple
957 * checks into a single check. The prefix consists of the
958 * prefix plus zeros for the bits in the cindex. The index
959 * is the difference between the key and this value. From
960 * this we can actually derive several pieces of data.
961 * if (index >= (1ul << bits))
962 * we have a mismatch in skip bits and failed
963 * else
964 * we know the value is cindex
965 *
966 * This check is safe even if bits == KEYLENGTH due to the
967 * fact that we can only allocate a node with 32 bits if a
968 * long is greater than 32 bits.
969 */
970 if (index >= (1ul << n->bits)) {
971 n = NULL;
972 break;
973 }
974
975 /* keep searching until we find a perfect match leaf or NULL */
976 } while (IS_TNODE(n));
977
978 *tp = pn;
979
980 return n;
981}
982
983/* Return the first fib alias matching TOS with
984 * priority less than or equal to PRIO.
985 */
986static struct fib_alias *fib_find_alias(struct hlist_head *fah, u8 slen,
987 u8 tos, u32 prio, u32 tb_id)
988{
989 struct fib_alias *fa;
990
991 if (!fah)
992 return NULL;
993
994 hlist_for_each_entry(fa, fah, fa_list) {
995 if (fa->fa_slen < slen)
996 continue;
997 if (fa->fa_slen != slen)
998 break;
999 if (fa->tb_id > tb_id)
1000 continue;
1001 if (fa->tb_id != tb_id)
1002 break;
1003 if (fa->fa_tos > tos)
1004 continue;
1005 if (fa->fa_info->fib_priority >= prio || fa->fa_tos < tos)
1006 return fa;
1007 }
1008
1009 return NULL;
1010}
1011
1012static void trie_rebalance(struct trie *t, struct key_vector *tn)
1013{
1014 while (!IS_TRIE(tn))
1015 tn = resize(t, tn);
1016}
1017
1018static int fib_insert_node(struct trie *t, struct key_vector *tp,
1019 struct fib_alias *new, t_key key)
1020{
1021 struct key_vector *n, *l;
1022
1023 l = leaf_new(key, new);
1024 if (!l)
1025 goto noleaf;
1026
1027 /* retrieve child from parent node */
1028 n = get_child(tp, get_index(key, tp));
1029
1030 /* Case 2: n is a LEAF or a TNODE and the key doesn't match.
1031 *
1032 * Add a new tnode here
1033 * first tnode need some special handling
1034 * leaves us in position for handling as case 3
1035 */
1036 if (n) {
1037 struct key_vector *tn;
1038
1039 tn = tnode_new(key, __fls(key ^ n->key), 1);
1040 if (!tn)
1041 goto notnode;
1042
1043 /* initialize routes out of node */
1044 NODE_INIT_PARENT(tn, tp);
1045 put_child(tn, get_index(key, tn) ^ 1, n);
1046
1047 /* start adding routes into the node */
1048 put_child_root(tp, key, tn);
1049 node_set_parent(n, tn);
1050
1051 /* parent now has a NULL spot where the leaf can go */
1052 tp = tn;
1053 }
1054
1055 /* Case 3: n is NULL, and will just insert a new leaf */
1056 node_push_suffix(tp, new->fa_slen);
1057 NODE_INIT_PARENT(l, tp);
1058 put_child_root(tp, key, l);
1059 trie_rebalance(t, tp);
1060
1061 return 0;
1062notnode:
1063 node_free(l);
1064noleaf:
1065 return -ENOMEM;
1066}
1067
1068/* fib notifier for ADD is sent before calling fib_insert_alias with
1069 * the expectation that the only possible failure ENOMEM
1070 */
1071static int fib_insert_alias(struct trie *t, struct key_vector *tp,
1072 struct key_vector *l, struct fib_alias *new,
1073 struct fib_alias *fa, t_key key)
1074{
1075 if (!l)
1076 return fib_insert_node(t, tp, new, key);
1077
1078 if (fa) {
1079 hlist_add_before_rcu(&new->fa_list, &fa->fa_list);
1080 } else {
1081 struct fib_alias *last;
1082
1083 hlist_for_each_entry(last, &l->leaf, fa_list) {
1084 if (new->fa_slen < last->fa_slen)
1085 break;
1086 if ((new->fa_slen == last->fa_slen) &&
1087 (new->tb_id > last->tb_id))
1088 break;
1089 fa = last;
1090 }
1091
1092 if (fa)
1093 hlist_add_behind_rcu(&new->fa_list, &fa->fa_list);
1094 else
1095 hlist_add_head_rcu(&new->fa_list, &l->leaf);
1096 }
1097
1098 /* if we added to the tail node then we need to update slen */
1099 if (l->slen < new->fa_slen) {
1100 l->slen = new->fa_slen;
1101 node_push_suffix(tp, new->fa_slen);
1102 }
1103
1104 return 0;
1105}
1106
1107static bool fib_valid_key_len(u32 key, u8 plen, struct netlink_ext_ack *extack)
1108{
1109 if (plen > KEYLENGTH) {
1110 NL_SET_ERR_MSG(extack, "Invalid prefix length");
1111 return false;
1112 }
1113
1114 if ((plen < KEYLENGTH) && (key << plen)) {
1115 NL_SET_ERR_MSG(extack,
1116 "Invalid prefix for given prefix length");
1117 return false;
1118 }
1119
1120 return true;
1121}
1122
1123/* Caller must hold RTNL. */
1124int fib_table_insert(struct net *net, struct fib_table *tb,
1125 struct fib_config *cfg, struct netlink_ext_ack *extack)
1126{
1127 enum fib_event_type event = FIB_EVENT_ENTRY_ADD;
1128 struct trie *t = (struct trie *)tb->tb_data;
1129 struct fib_alias *fa, *new_fa;
1130 struct key_vector *l, *tp;
1131 u16 nlflags = NLM_F_EXCL;
1132 struct fib_info *fi;
1133 u8 plen = cfg->fc_dst_len;
1134 u8 slen = KEYLENGTH - plen;
1135 u8 tos = cfg->fc_tos;
1136 u32 key;
1137 int err;
1138
1139 key = ntohl(cfg->fc_dst);
1140
1141 if (!fib_valid_key_len(key, plen, extack))
1142 return -EINVAL;
1143
1144 pr_debug("Insert table=%u %08x/%d\n", tb->tb_id, key, plen);
1145
1146 fi = fib_create_info(cfg, extack);
1147 if (IS_ERR(fi)) {
1148 err = PTR_ERR(fi);
1149 goto err;
1150 }
1151
1152 l = fib_find_node(t, &tp, key);
1153 fa = l ? fib_find_alias(&l->leaf, slen, tos, fi->fib_priority,
1154 tb->tb_id) : NULL;
1155
1156 /* Now fa, if non-NULL, points to the first fib alias
1157 * with the same keys [prefix,tos,priority], if such key already
1158 * exists or to the node before which we will insert new one.
1159 *
1160 * If fa is NULL, we will need to allocate a new one and
1161 * insert to the tail of the section matching the suffix length
1162 * of the new alias.
1163 */
1164
1165 if (fa && fa->fa_tos == tos &&
1166 fa->fa_info->fib_priority == fi->fib_priority) {
1167 struct fib_alias *fa_first, *fa_match;
1168
1169 err = -EEXIST;
1170 if (cfg->fc_nlflags & NLM_F_EXCL)
1171 goto out;
1172
1173 nlflags &= ~NLM_F_EXCL;
1174
1175 /* We have 2 goals:
1176 * 1. Find exact match for type, scope, fib_info to avoid
1177 * duplicate routes
1178 * 2. Find next 'fa' (or head), NLM_F_APPEND inserts before it
1179 */
1180 fa_match = NULL;
1181 fa_first = fa;
1182 hlist_for_each_entry_from(fa, fa_list) {
1183 if ((fa->fa_slen != slen) ||
1184 (fa->tb_id != tb->tb_id) ||
1185 (fa->fa_tos != tos))
1186 break;
1187 if (fa->fa_info->fib_priority != fi->fib_priority)
1188 break;
1189 if (fa->fa_type == cfg->fc_type &&
1190 fa->fa_info == fi) {
1191 fa_match = fa;
1192 break;
1193 }
1194 }
1195
1196 if (cfg->fc_nlflags & NLM_F_REPLACE) {
1197 struct fib_info *fi_drop;
1198 u8 state;
1199
1200 nlflags |= NLM_F_REPLACE;
1201 fa = fa_first;
1202 if (fa_match) {
1203 if (fa == fa_match)
1204 err = 0;
1205 goto out;
1206 }
1207 err = -ENOBUFS;
1208 new_fa = kmem_cache_alloc(fn_alias_kmem, GFP_KERNEL);
1209 if (!new_fa)
1210 goto out;
1211
1212 fi_drop = fa->fa_info;
1213 new_fa->fa_tos = fa->fa_tos;
1214 new_fa->fa_info = fi;
1215 new_fa->fa_type = cfg->fc_type;
1216 state = fa->fa_state;
1217 new_fa->fa_state = state & ~FA_S_ACCESSED;
1218 new_fa->fa_slen = fa->fa_slen;
1219 new_fa->tb_id = tb->tb_id;
1220 new_fa->fa_default = -1;
1221
1222 err = call_fib_entry_notifiers(net,
1223 FIB_EVENT_ENTRY_REPLACE,
1224 key, plen, new_fa,
1225 extack);
1226 if (err)
1227 goto out_free_new_fa;
1228
1229 rtmsg_fib(RTM_NEWROUTE, htonl(key), new_fa, plen,
1230 tb->tb_id, &cfg->fc_nlinfo, nlflags);
1231
1232 hlist_replace_rcu(&fa->fa_list, &new_fa->fa_list);
1233
1234 alias_free_mem_rcu(fa);
1235
1236 fib_release_info(fi_drop);
1237 if (state & FA_S_ACCESSED)
1238 rt_cache_flush(cfg->fc_nlinfo.nl_net);
1239
1240 goto succeeded;
1241 }
1242 /* Error if we find a perfect match which
1243 * uses the same scope, type, and nexthop
1244 * information.
1245 */
1246 if (fa_match)
1247 goto out;
1248
1249 if (cfg->fc_nlflags & NLM_F_APPEND) {
1250 event = FIB_EVENT_ENTRY_APPEND;
1251 nlflags |= NLM_F_APPEND;
1252 } else {
1253 fa = fa_first;
1254 }
1255 }
1256 err = -ENOENT;
1257 if (!(cfg->fc_nlflags & NLM_F_CREATE))
1258 goto out;
1259
1260 nlflags |= NLM_F_CREATE;
1261 err = -ENOBUFS;
1262 new_fa = kmem_cache_alloc(fn_alias_kmem, GFP_KERNEL);
1263 if (!new_fa)
1264 goto out;
1265
1266 new_fa->fa_info = fi;
1267 new_fa->fa_tos = tos;
1268 new_fa->fa_type = cfg->fc_type;
1269 new_fa->fa_state = 0;
1270 new_fa->fa_slen = slen;
1271 new_fa->tb_id = tb->tb_id;
1272 new_fa->fa_default = -1;
1273
1274 err = call_fib_entry_notifiers(net, event, key, plen, new_fa, extack);
1275 if (err)
1276 goto out_free_new_fa;
1277
1278 /* Insert new entry to the list. */
1279 err = fib_insert_alias(t, tp, l, new_fa, fa, key);
1280 if (err)
1281 goto out_fib_notif;
1282
1283 if (!plen)
1284 tb->tb_num_default++;
1285
1286 rt_cache_flush(cfg->fc_nlinfo.nl_net);
1287 rtmsg_fib(RTM_NEWROUTE, htonl(key), new_fa, plen, new_fa->tb_id,
1288 &cfg->fc_nlinfo, nlflags);
1289succeeded:
1290 return 0;
1291
1292out_fib_notif:
1293 /* notifier was sent that entry would be added to trie, but
1294 * the add failed and need to recover. Only failure for
1295 * fib_insert_alias is ENOMEM.
1296 */
1297 NL_SET_ERR_MSG(extack, "Failed to insert route into trie");
1298 call_fib_entry_notifiers(net, FIB_EVENT_ENTRY_DEL, key,
1299 plen, new_fa, NULL);
1300out_free_new_fa:
1301 kmem_cache_free(fn_alias_kmem, new_fa);
1302out:
1303 fib_release_info(fi);
1304err:
1305 return err;
1306}
1307
1308static inline t_key prefix_mismatch(t_key key, struct key_vector *n)
1309{
1310 t_key prefix = n->key;
1311
1312 return (key ^ prefix) & (prefix | -prefix);
1313}
1314
1315/* should be called with rcu_read_lock */
1316int fib_table_lookup(struct fib_table *tb, const struct flowi4 *flp,
1317 struct fib_result *res, int fib_flags)
1318{
1319 struct trie *t = (struct trie *) tb->tb_data;
1320#ifdef CONFIG_IP_FIB_TRIE_STATS
1321 struct trie_use_stats __percpu *stats = t->stats;
1322#endif
1323 const t_key key = ntohl(flp->daddr);
1324 struct key_vector *n, *pn;
1325 struct fib_alias *fa;
1326 unsigned long index;
1327 t_key cindex;
1328
1329 trace_fib_table_lookup(tb->tb_id, flp);
1330
1331 pn = t->kv;
1332 cindex = 0;
1333
1334 n = get_child_rcu(pn, cindex);
1335 if (!n)
1336 return -EAGAIN;
1337
1338#ifdef CONFIG_IP_FIB_TRIE_STATS
1339 this_cpu_inc(stats->gets);
1340#endif
1341
1342 /* Step 1: Travel to the longest prefix match in the trie */
1343 for (;;) {
1344 index = get_cindex(key, n);
1345
1346 /* This bit of code is a bit tricky but it combines multiple
1347 * checks into a single check. The prefix consists of the
1348 * prefix plus zeros for the "bits" in the prefix. The index
1349 * is the difference between the key and this value. From
1350 * this we can actually derive several pieces of data.
1351 * if (index >= (1ul << bits))
1352 * we have a mismatch in skip bits and failed
1353 * else
1354 * we know the value is cindex
1355 *
1356 * This check is safe even if bits == KEYLENGTH due to the
1357 * fact that we can only allocate a node with 32 bits if a
1358 * long is greater than 32 bits.
1359 */
1360 if (index >= (1ul << n->bits))
1361 break;
1362
1363 /* we have found a leaf. Prefixes have already been compared */
1364 if (IS_LEAF(n))
1365 goto found;
1366
1367 /* only record pn and cindex if we are going to be chopping
1368 * bits later. Otherwise we are just wasting cycles.
1369 */
1370 if (n->slen > n->pos) {
1371 pn = n;
1372 cindex = index;
1373 }
1374
1375 n = get_child_rcu(n, index);
1376 if (unlikely(!n))
1377 goto backtrace;
1378 }
1379
1380 /* Step 2: Sort out leaves and begin backtracing for longest prefix */
1381 for (;;) {
1382 /* record the pointer where our next node pointer is stored */
1383 struct key_vector __rcu **cptr = n->tnode;
1384
1385 /* This test verifies that none of the bits that differ
1386 * between the key and the prefix exist in the region of
1387 * the lsb and higher in the prefix.
1388 */
1389 if (unlikely(prefix_mismatch(key, n)) || (n->slen == n->pos))
1390 goto backtrace;
1391
1392 /* exit out and process leaf */
1393 if (unlikely(IS_LEAF(n)))
1394 break;
1395
1396 /* Don't bother recording parent info. Since we are in
1397 * prefix match mode we will have to come back to wherever
1398 * we started this traversal anyway
1399 */
1400
1401 while ((n = rcu_dereference(*cptr)) == NULL) {
1402backtrace:
1403#ifdef CONFIG_IP_FIB_TRIE_STATS
1404 if (!n)
1405 this_cpu_inc(stats->null_node_hit);
1406#endif
1407 /* If we are at cindex 0 there are no more bits for
1408 * us to strip at this level so we must ascend back
1409 * up one level to see if there are any more bits to
1410 * be stripped there.
1411 */
1412 while (!cindex) {
1413 t_key pkey = pn->key;
1414
1415 /* If we don't have a parent then there is
1416 * nothing for us to do as we do not have any
1417 * further nodes to parse.
1418 */
1419 if (IS_TRIE(pn))
1420 return -EAGAIN;
1421#ifdef CONFIG_IP_FIB_TRIE_STATS
1422 this_cpu_inc(stats->backtrack);
1423#endif
1424 /* Get Child's index */
1425 pn = node_parent_rcu(pn);
1426 cindex = get_index(pkey, pn);
1427 }
1428
1429 /* strip the least significant bit from the cindex */
1430 cindex &= cindex - 1;
1431
1432 /* grab pointer for next child node */
1433 cptr = &pn->tnode[cindex];
1434 }
1435 }
1436
1437found:
1438 /* this line carries forward the xor from earlier in the function */
1439 index = key ^ n->key;
1440
1441 /* Step 3: Process the leaf, if that fails fall back to backtracing */
1442 hlist_for_each_entry_rcu(fa, &n->leaf, fa_list) {
1443 struct fib_info *fi = fa->fa_info;
1444 int nhsel, err;
1445
1446 if ((BITS_PER_LONG > KEYLENGTH) || (fa->fa_slen < KEYLENGTH)) {
1447 if (index >= (1ul << fa->fa_slen))
1448 continue;
1449 }
1450 if (fa->fa_tos && fa->fa_tos != flp->flowi4_tos)
1451 continue;
1452 if (fi->fib_dead)
1453 continue;
1454 if (fa->fa_info->fib_scope < flp->flowi4_scope)
1455 continue;
1456 fib_alias_accessed(fa);
1457 err = fib_props[fa->fa_type].error;
1458 if (unlikely(err < 0)) {
1459#ifdef CONFIG_IP_FIB_TRIE_STATS
1460 this_cpu_inc(stats->semantic_match_passed);
1461#endif
1462 return err;
1463 }
1464 if (fi->fib_flags & RTNH_F_DEAD)
1465 continue;
1466 for (nhsel = 0; nhsel < fi->fib_nhs; nhsel++) {
1467 const struct fib_nh *nh = &fi->fib_nh[nhsel];
1468 struct in_device *in_dev = __in_dev_get_rcu(nh->nh_dev);
1469
1470 if (nh->nh_flags & RTNH_F_DEAD)
1471 continue;
1472 if (in_dev &&
1473 IN_DEV_IGNORE_ROUTES_WITH_LINKDOWN(in_dev) &&
1474 nh->nh_flags & RTNH_F_LINKDOWN &&
1475 !(fib_flags & FIB_LOOKUP_IGNORE_LINKSTATE))
1476 continue;
1477 if (!(flp->flowi4_flags & FLOWI_FLAG_SKIP_NH_OIF)) {
1478 if (flp->flowi4_oif &&
1479 flp->flowi4_oif != nh->nh_oif)
1480 continue;
1481 }
1482
1483 if (!(fib_flags & FIB_LOOKUP_NOREF))
1484 refcount_inc(&fi->fib_clntref);
1485
1486 res->prefix = htonl(n->key);
1487 res->prefixlen = KEYLENGTH - fa->fa_slen;
1488 res->nh_sel = nhsel;
1489 res->type = fa->fa_type;
1490 res->scope = fi->fib_scope;
1491 res->fi = fi;
1492 res->table = tb;
1493 res->fa_head = &n->leaf;
1494#ifdef CONFIG_IP_FIB_TRIE_STATS
1495 this_cpu_inc(stats->semantic_match_passed);
1496#endif
1497 trace_fib_table_lookup_nh(nh);
1498
1499 return err;
1500 }
1501 }
1502#ifdef CONFIG_IP_FIB_TRIE_STATS
1503 this_cpu_inc(stats->semantic_match_miss);
1504#endif
1505 goto backtrace;
1506}
1507EXPORT_SYMBOL_GPL(fib_table_lookup);
1508
1509static void fib_remove_alias(struct trie *t, struct key_vector *tp,
1510 struct key_vector *l, struct fib_alias *old)
1511{
1512 /* record the location of the previous list_info entry */
1513 struct hlist_node **pprev = old->fa_list.pprev;
1514 struct fib_alias *fa = hlist_entry(pprev, typeof(*fa), fa_list.next);
1515
1516 /* remove the fib_alias from the list */
1517 hlist_del_rcu(&old->fa_list);
1518
1519 /* if we emptied the list this leaf will be freed and we can sort
1520 * out parent suffix lengths as a part of trie_rebalance
1521 */
1522 if (hlist_empty(&l->leaf)) {
1523 if (tp->slen == l->slen)
1524 node_pull_suffix(tp, tp->pos);
1525 put_child_root(tp, l->key, NULL);
1526 node_free(l);
1527 trie_rebalance(t, tp);
1528 return;
1529 }
1530
1531 /* only access fa if it is pointing at the last valid hlist_node */
1532 if (*pprev)
1533 return;
1534
1535 /* update the trie with the latest suffix length */
1536 l->slen = fa->fa_slen;
1537 node_pull_suffix(tp, fa->fa_slen);
1538}
1539
1540/* Caller must hold RTNL. */
1541int fib_table_delete(struct net *net, struct fib_table *tb,
1542 struct fib_config *cfg, struct netlink_ext_ack *extack)
1543{
1544 struct trie *t = (struct trie *) tb->tb_data;
1545 struct fib_alias *fa, *fa_to_delete;
1546 struct key_vector *l, *tp;
1547 u8 plen = cfg->fc_dst_len;
1548 u8 slen = KEYLENGTH - plen;
1549 u8 tos = cfg->fc_tos;
1550 u32 key;
1551
1552 key = ntohl(cfg->fc_dst);
1553
1554 if (!fib_valid_key_len(key, plen, extack))
1555 return -EINVAL;
1556
1557 l = fib_find_node(t, &tp, key);
1558 if (!l)
1559 return -ESRCH;
1560
1561 fa = fib_find_alias(&l->leaf, slen, tos, 0, tb->tb_id);
1562 if (!fa)
1563 return -ESRCH;
1564
1565 pr_debug("Deleting %08x/%d tos=%d t=%p\n", key, plen, tos, t);
1566
1567 fa_to_delete = NULL;
1568 hlist_for_each_entry_from(fa, fa_list) {
1569 struct fib_info *fi = fa->fa_info;
1570
1571 if ((fa->fa_slen != slen) ||
1572 (fa->tb_id != tb->tb_id) ||
1573 (fa->fa_tos != tos))
1574 break;
1575
1576 if ((!cfg->fc_type || fa->fa_type == cfg->fc_type) &&
1577 (cfg->fc_scope == RT_SCOPE_NOWHERE ||
1578 fa->fa_info->fib_scope == cfg->fc_scope) &&
1579 (!cfg->fc_prefsrc ||
1580 fi->fib_prefsrc == cfg->fc_prefsrc) &&
1581 (!cfg->fc_protocol ||
1582 fi->fib_protocol == cfg->fc_protocol) &&
1583 fib_nh_match(cfg, fi, extack) == 0 &&
1584 fib_metrics_match(cfg, fi)) {
1585 fa_to_delete = fa;
1586 break;
1587 }
1588 }
1589
1590 if (!fa_to_delete)
1591 return -ESRCH;
1592
1593 call_fib_entry_notifiers(net, FIB_EVENT_ENTRY_DEL, key, plen,
1594 fa_to_delete, extack);
1595 rtmsg_fib(RTM_DELROUTE, htonl(key), fa_to_delete, plen, tb->tb_id,
1596 &cfg->fc_nlinfo, 0);
1597
1598 if (!plen)
1599 tb->tb_num_default--;
1600
1601 fib_remove_alias(t, tp, l, fa_to_delete);
1602
1603 if (fa_to_delete->fa_state & FA_S_ACCESSED)
1604 rt_cache_flush(cfg->fc_nlinfo.nl_net);
1605
1606 fib_release_info(fa_to_delete->fa_info);
1607 alias_free_mem_rcu(fa_to_delete);
1608 return 0;
1609}
1610
1611/* Scan for the next leaf starting at the provided key value */
1612static struct key_vector *leaf_walk_rcu(struct key_vector **tn, t_key key)
1613{
1614 struct key_vector *pn, *n = *tn;
1615 unsigned long cindex;
1616
1617 /* this loop is meant to try and find the key in the trie */
1618 do {
1619 /* record parent and next child index */
1620 pn = n;
1621 cindex = (key > pn->key) ? get_index(key, pn) : 0;
1622
1623 if (cindex >> pn->bits)
1624 break;
1625
1626 /* descend into the next child */
1627 n = get_child_rcu(pn, cindex++);
1628 if (!n)
1629 break;
1630
1631 /* guarantee forward progress on the keys */
1632 if (IS_LEAF(n) && (n->key >= key))
1633 goto found;
1634 } while (IS_TNODE(n));
1635
1636 /* this loop will search for the next leaf with a greater key */
1637 while (!IS_TRIE(pn)) {
1638 /* if we exhausted the parent node we will need to climb */
1639 if (cindex >= (1ul << pn->bits)) {
1640 t_key pkey = pn->key;
1641
1642 pn = node_parent_rcu(pn);
1643 cindex = get_index(pkey, pn) + 1;
1644 continue;
1645 }
1646
1647 /* grab the next available node */
1648 n = get_child_rcu(pn, cindex++);
1649 if (!n)
1650 continue;
1651
1652 /* no need to compare keys since we bumped the index */
1653 if (IS_LEAF(n))
1654 goto found;
1655
1656 /* Rescan start scanning in new node */
1657 pn = n;
1658 cindex = 0;
1659 }
1660
1661 *tn = pn;
1662 return NULL; /* Root of trie */
1663found:
1664 /* if we are at the limit for keys just return NULL for the tnode */
1665 *tn = pn;
1666 return n;
1667}
1668
1669static void fib_trie_free(struct fib_table *tb)
1670{
1671 struct trie *t = (struct trie *)tb->tb_data;
1672 struct key_vector *pn = t->kv;
1673 unsigned long cindex = 1;
1674 struct hlist_node *tmp;
1675 struct fib_alias *fa;
1676
1677 /* walk trie in reverse order and free everything */
1678 for (;;) {
1679 struct key_vector *n;
1680
1681 if (!(cindex--)) {
1682 t_key pkey = pn->key;
1683
1684 if (IS_TRIE(pn))
1685 break;
1686
1687 n = pn;
1688 pn = node_parent(pn);
1689
1690 /* drop emptied tnode */
1691 put_child_root(pn, n->key, NULL);
1692 node_free(n);
1693
1694 cindex = get_index(pkey, pn);
1695
1696 continue;
1697 }
1698
1699 /* grab the next available node */
1700 n = get_child(pn, cindex);
1701 if (!n)
1702 continue;
1703
1704 if (IS_TNODE(n)) {
1705 /* record pn and cindex for leaf walking */
1706 pn = n;
1707 cindex = 1ul << n->bits;
1708
1709 continue;
1710 }
1711
1712 hlist_for_each_entry_safe(fa, tmp, &n->leaf, fa_list) {
1713 hlist_del_rcu(&fa->fa_list);
1714 alias_free_mem_rcu(fa);
1715 }
1716
1717 put_child_root(pn, n->key, NULL);
1718 node_free(n);
1719 }
1720
1721#ifdef CONFIG_IP_FIB_TRIE_STATS
1722 free_percpu(t->stats);
1723#endif
1724 kfree(tb);
1725}
1726
1727struct fib_table *fib_trie_unmerge(struct fib_table *oldtb)
1728{
1729 struct trie *ot = (struct trie *)oldtb->tb_data;
1730 struct key_vector *l, *tp = ot->kv;
1731 struct fib_table *local_tb;
1732 struct fib_alias *fa;
1733 struct trie *lt;
1734 t_key key = 0;
1735
1736 if (oldtb->tb_data == oldtb->__data)
1737 return oldtb;
1738
1739 local_tb = fib_trie_table(RT_TABLE_LOCAL, NULL);
1740 if (!local_tb)
1741 return NULL;
1742
1743 lt = (struct trie *)local_tb->tb_data;
1744
1745 while ((l = leaf_walk_rcu(&tp, key)) != NULL) {
1746 struct key_vector *local_l = NULL, *local_tp;
1747
1748 hlist_for_each_entry_rcu(fa, &l->leaf, fa_list) {
1749 struct fib_alias *new_fa;
1750
1751 if (local_tb->tb_id != fa->tb_id)
1752 continue;
1753
1754 /* clone fa for new local table */
1755 new_fa = kmem_cache_alloc(fn_alias_kmem, GFP_KERNEL);
1756 if (!new_fa)
1757 goto out;
1758
1759 memcpy(new_fa, fa, sizeof(*fa));
1760
1761 /* insert clone into table */
1762 if (!local_l)
1763 local_l = fib_find_node(lt, &local_tp, l->key);
1764
1765 if (fib_insert_alias(lt, local_tp, local_l, new_fa,
1766 NULL, l->key)) {
1767 kmem_cache_free(fn_alias_kmem, new_fa);
1768 goto out;
1769 }
1770 }
1771
1772 /* stop loop if key wrapped back to 0 */
1773 key = l->key + 1;
1774 if (key < l->key)
1775 break;
1776 }
1777
1778 return local_tb;
1779out:
1780 fib_trie_free(local_tb);
1781
1782 return NULL;
1783}
1784
1785/* Caller must hold RTNL */
1786void fib_table_flush_external(struct fib_table *tb)
1787{
1788 struct trie *t = (struct trie *)tb->tb_data;
1789 struct key_vector *pn = t->kv;
1790 unsigned long cindex = 1;
1791 struct hlist_node *tmp;
1792 struct fib_alias *fa;
1793
1794 /* walk trie in reverse order */
1795 for (;;) {
1796 unsigned char slen = 0;
1797 struct key_vector *n;
1798
1799 if (!(cindex--)) {
1800 t_key pkey = pn->key;
1801
1802 /* cannot resize the trie vector */
1803 if (IS_TRIE(pn))
1804 break;
1805
1806 /* update the suffix to address pulled leaves */
1807 if (pn->slen > pn->pos)
1808 update_suffix(pn);
1809
1810 /* resize completed node */
1811 pn = resize(t, pn);
1812 cindex = get_index(pkey, pn);
1813
1814 continue;
1815 }
1816
1817 /* grab the next available node */
1818 n = get_child(pn, cindex);
1819 if (!n)
1820 continue;
1821
1822 if (IS_TNODE(n)) {
1823 /* record pn and cindex for leaf walking */
1824 pn = n;
1825 cindex = 1ul << n->bits;
1826
1827 continue;
1828 }
1829
1830 hlist_for_each_entry_safe(fa, tmp, &n->leaf, fa_list) {
1831 /* if alias was cloned to local then we just
1832 * need to remove the local copy from main
1833 */
1834 if (tb->tb_id != fa->tb_id) {
1835 hlist_del_rcu(&fa->fa_list);
1836 alias_free_mem_rcu(fa);
1837 continue;
1838 }
1839
1840 /* record local slen */
1841 slen = fa->fa_slen;
1842 }
1843
1844 /* update leaf slen */
1845 n->slen = slen;
1846
1847 if (hlist_empty(&n->leaf)) {
1848 put_child_root(pn, n->key, NULL);
1849 node_free(n);
1850 }
1851 }
1852}
1853
1854/* Caller must hold RTNL. */
1855int fib_table_flush(struct net *net, struct fib_table *tb)
1856{
1857 struct trie *t = (struct trie *)tb->tb_data;
1858 struct key_vector *pn = t->kv;
1859 unsigned long cindex = 1;
1860 struct hlist_node *tmp;
1861 struct fib_alias *fa;
1862 int found = 0;
1863
1864 /* walk trie in reverse order */
1865 for (;;) {
1866 unsigned char slen = 0;
1867 struct key_vector *n;
1868
1869 if (!(cindex--)) {
1870 t_key pkey = pn->key;
1871
1872 /* cannot resize the trie vector */
1873 if (IS_TRIE(pn))
1874 break;
1875
1876 /* update the suffix to address pulled leaves */
1877 if (pn->slen > pn->pos)
1878 update_suffix(pn);
1879
1880 /* resize completed node */
1881 pn = resize(t, pn);
1882 cindex = get_index(pkey, pn);
1883
1884 continue;
1885 }
1886
1887 /* grab the next available node */
1888 n = get_child(pn, cindex);
1889 if (!n)
1890 continue;
1891
1892 if (IS_TNODE(n)) {
1893 /* record pn and cindex for leaf walking */
1894 pn = n;
1895 cindex = 1ul << n->bits;
1896
1897 continue;
1898 }
1899
1900 hlist_for_each_entry_safe(fa, tmp, &n->leaf, fa_list) {
1901 struct fib_info *fi = fa->fa_info;
1902
1903 if (!fi || !(fi->fib_flags & RTNH_F_DEAD) ||
1904 tb->tb_id != fa->tb_id) {
1905 slen = fa->fa_slen;
1906 continue;
1907 }
1908
1909 call_fib_entry_notifiers(net, FIB_EVENT_ENTRY_DEL,
1910 n->key,
1911 KEYLENGTH - fa->fa_slen, fa,
1912 NULL);
1913 hlist_del_rcu(&fa->fa_list);
1914 fib_release_info(fa->fa_info);
1915 alias_free_mem_rcu(fa);
1916 found++;
1917 }
1918
1919 /* update leaf slen */
1920 n->slen = slen;
1921
1922 if (hlist_empty(&n->leaf)) {
1923 put_child_root(pn, n->key, NULL);
1924 node_free(n);
1925 }
1926 }
1927
1928 pr_debug("trie_flush found=%d\n", found);
1929 return found;
1930}
1931
1932static void fib_leaf_notify(struct net *net, struct key_vector *l,
1933 struct fib_table *tb, struct notifier_block *nb)
1934{
1935 struct fib_alias *fa;
1936
1937 hlist_for_each_entry_rcu(fa, &l->leaf, fa_list) {
1938 struct fib_info *fi = fa->fa_info;
1939
1940 if (!fi)
1941 continue;
1942
1943 /* local and main table can share the same trie,
1944 * so don't notify twice for the same entry.
1945 */
1946 if (tb->tb_id != fa->tb_id)
1947 continue;
1948
1949 call_fib_entry_notifier(nb, net, FIB_EVENT_ENTRY_ADD, l->key,
1950 KEYLENGTH - fa->fa_slen, fa);
1951 }
1952}
1953
1954static void fib_table_notify(struct net *net, struct fib_table *tb,
1955 struct notifier_block *nb)
1956{
1957 struct trie *t = (struct trie *)tb->tb_data;
1958 struct key_vector *l, *tp = t->kv;
1959 t_key key = 0;
1960
1961 while ((l = leaf_walk_rcu(&tp, key)) != NULL) {
1962 fib_leaf_notify(net, l, tb, nb);
1963
1964 key = l->key + 1;
1965 /* stop in case of wrap around */
1966 if (key < l->key)
1967 break;
1968 }
1969}
1970
1971void fib_notify(struct net *net, struct notifier_block *nb)
1972{
1973 unsigned int h;
1974
1975 for (h = 0; h < FIB_TABLE_HASHSZ; h++) {
1976 struct hlist_head *head = &net->ipv4.fib_table_hash[h];
1977 struct fib_table *tb;
1978
1979 hlist_for_each_entry_rcu(tb, head, tb_hlist)
1980 fib_table_notify(net, tb, nb);
1981 }
1982}
1983
1984static void __trie_free_rcu(struct rcu_head *head)
1985{
1986 struct fib_table *tb = container_of(head, struct fib_table, rcu);
1987#ifdef CONFIG_IP_FIB_TRIE_STATS
1988 struct trie *t = (struct trie *)tb->tb_data;
1989
1990 if (tb->tb_data == tb->__data)
1991 free_percpu(t->stats);
1992#endif /* CONFIG_IP_FIB_TRIE_STATS */
1993 kfree(tb);
1994}
1995
1996void fib_free_table(struct fib_table *tb)
1997{
1998 call_rcu(&tb->rcu, __trie_free_rcu);
1999}
2000
2001static int fn_trie_dump_leaf(struct key_vector *l, struct fib_table *tb,
2002 struct sk_buff *skb, struct netlink_callback *cb)
2003{
2004 __be32 xkey = htonl(l->key);
2005 struct fib_alias *fa;
2006 int i, s_i;
2007
2008 s_i = cb->args[4];
2009 i = 0;
2010
2011 /* rcu_read_lock is hold by caller */
2012 hlist_for_each_entry_rcu(fa, &l->leaf, fa_list) {
2013 int err;
2014
2015 if (i < s_i) {
2016 i++;
2017 continue;
2018 }
2019
2020 if (tb->tb_id != fa->tb_id) {
2021 i++;
2022 continue;
2023 }
2024
2025 err = fib_dump_info(skb, NETLINK_CB(cb->skb).portid,
2026 cb->nlh->nlmsg_seq, RTM_NEWROUTE,
2027 tb->tb_id, fa->fa_type,
2028 xkey, KEYLENGTH - fa->fa_slen,
2029 fa->fa_tos, fa->fa_info, NLM_F_MULTI);
2030 if (err < 0) {
2031 cb->args[4] = i;
2032 return err;
2033 }
2034 i++;
2035 }
2036
2037 cb->args[4] = i;
2038 return skb->len;
2039}
2040
2041/* rcu_read_lock needs to be hold by caller from readside */
2042int fib_table_dump(struct fib_table *tb, struct sk_buff *skb,
2043 struct netlink_callback *cb)
2044{
2045 struct trie *t = (struct trie *)tb->tb_data;
2046 struct key_vector *l, *tp = t->kv;
2047 /* Dump starting at last key.
2048 * Note: 0.0.0.0/0 (ie default) is first key.
2049 */
2050 int count = cb->args[2];
2051 t_key key = cb->args[3];
2052
2053 while ((l = leaf_walk_rcu(&tp, key)) != NULL) {
2054 int err;
2055
2056 err = fn_trie_dump_leaf(l, tb, skb, cb);
2057 if (err < 0) {
2058 cb->args[3] = key;
2059 cb->args[2] = count;
2060 return err;
2061 }
2062
2063 ++count;
2064 key = l->key + 1;
2065
2066 memset(&cb->args[4], 0,
2067 sizeof(cb->args) - 4*sizeof(cb->args[0]));
2068
2069 /* stop loop if key wrapped back to 0 */
2070 if (key < l->key)
2071 break;
2072 }
2073
2074 cb->args[3] = key;
2075 cb->args[2] = count;
2076
2077 return skb->len;
2078}
2079
2080void __init fib_trie_init(void)
2081{
2082 fn_alias_kmem = kmem_cache_create("ip_fib_alias",
2083 sizeof(struct fib_alias),
2084 0, SLAB_PANIC, NULL);
2085
2086 trie_leaf_kmem = kmem_cache_create("ip_fib_trie",
2087 LEAF_SIZE,
2088 0, SLAB_PANIC, NULL);
2089}
2090
2091struct fib_table *fib_trie_table(u32 id, struct fib_table *alias)
2092{
2093 struct fib_table *tb;
2094 struct trie *t;
2095 size_t sz = sizeof(*tb);
2096
2097 if (!alias)
2098 sz += sizeof(struct trie);
2099
2100 tb = kzalloc(sz, GFP_KERNEL);
2101 if (!tb)
2102 return NULL;
2103
2104 tb->tb_id = id;
2105 tb->tb_num_default = 0;
2106 tb->tb_data = (alias ? alias->__data : tb->__data);
2107
2108 if (alias)
2109 return tb;
2110
2111 t = (struct trie *) tb->tb_data;
2112 t->kv[0].pos = KEYLENGTH;
2113 t->kv[0].slen = KEYLENGTH;
2114#ifdef CONFIG_IP_FIB_TRIE_STATS
2115 t->stats = alloc_percpu(struct trie_use_stats);
2116 if (!t->stats) {
2117 kfree(tb);
2118 tb = NULL;
2119 }
2120#endif
2121
2122 return tb;
2123}
2124
2125#ifdef CONFIG_PROC_FS
2126/* Depth first Trie walk iterator */
2127struct fib_trie_iter {
2128 struct seq_net_private p;
2129 struct fib_table *tb;
2130 struct key_vector *tnode;
2131 unsigned int index;
2132 unsigned int depth;
2133};
2134
2135static struct key_vector *fib_trie_get_next(struct fib_trie_iter *iter)
2136{
2137 unsigned long cindex = iter->index;
2138 struct key_vector *pn = iter->tnode;
2139 t_key pkey;
2140
2141 pr_debug("get_next iter={node=%p index=%d depth=%d}\n",
2142 iter->tnode, iter->index, iter->depth);
2143
2144 while (!IS_TRIE(pn)) {
2145 while (cindex < child_length(pn)) {
2146 struct key_vector *n = get_child_rcu(pn, cindex++);
2147
2148 if (!n)
2149 continue;
2150
2151 if (IS_LEAF(n)) {
2152 iter->tnode = pn;
2153 iter->index = cindex;
2154 } else {
2155 /* push down one level */
2156 iter->tnode = n;
2157 iter->index = 0;
2158 ++iter->depth;
2159 }
2160
2161 return n;
2162 }
2163
2164 /* Current node exhausted, pop back up */
2165 pkey = pn->key;
2166 pn = node_parent_rcu(pn);
2167 cindex = get_index(pkey, pn) + 1;
2168 --iter->depth;
2169 }
2170
2171 /* record root node so further searches know we are done */
2172 iter->tnode = pn;
2173 iter->index = 0;
2174
2175 return NULL;
2176}
2177
2178static struct key_vector *fib_trie_get_first(struct fib_trie_iter *iter,
2179 struct trie *t)
2180{
2181 struct key_vector *n, *pn;
2182
2183 if (!t)
2184 return NULL;
2185
2186 pn = t->kv;
2187 n = rcu_dereference(pn->tnode[0]);
2188 if (!n)
2189 return NULL;
2190
2191 if (IS_TNODE(n)) {
2192 iter->tnode = n;
2193 iter->index = 0;
2194 iter->depth = 1;
2195 } else {
2196 iter->tnode = pn;
2197 iter->index = 0;
2198 iter->depth = 0;
2199 }
2200
2201 return n;
2202}
2203
2204static void trie_collect_stats(struct trie *t, struct trie_stat *s)
2205{
2206 struct key_vector *n;
2207 struct fib_trie_iter iter;
2208
2209 memset(s, 0, sizeof(*s));
2210
2211 rcu_read_lock();
2212 for (n = fib_trie_get_first(&iter, t); n; n = fib_trie_get_next(&iter)) {
2213 if (IS_LEAF(n)) {
2214 struct fib_alias *fa;
2215
2216 s->leaves++;
2217 s->totdepth += iter.depth;
2218 if (iter.depth > s->maxdepth)
2219 s->maxdepth = iter.depth;
2220
2221 hlist_for_each_entry_rcu(fa, &n->leaf, fa_list)
2222 ++s->prefixes;
2223 } else {
2224 s->tnodes++;
2225 if (n->bits < MAX_STAT_DEPTH)
2226 s->nodesizes[n->bits]++;
2227 s->nullpointers += tn_info(n)->empty_children;
2228 }
2229 }
2230 rcu_read_unlock();
2231}
2232
2233/*
2234 * This outputs /proc/net/fib_triestats
2235 */
2236static void trie_show_stats(struct seq_file *seq, struct trie_stat *stat)
2237{
2238 unsigned int i, max, pointers, bytes, avdepth;
2239
2240 if (stat->leaves)
2241 avdepth = stat->totdepth*100 / stat->leaves;
2242 else
2243 avdepth = 0;
2244
2245 seq_printf(seq, "\tAver depth: %u.%02d\n",
2246 avdepth / 100, avdepth % 100);
2247 seq_printf(seq, "\tMax depth: %u\n", stat->maxdepth);
2248
2249 seq_printf(seq, "\tLeaves: %u\n", stat->leaves);
2250 bytes = LEAF_SIZE * stat->leaves;
2251
2252 seq_printf(seq, "\tPrefixes: %u\n", stat->prefixes);
2253 bytes += sizeof(struct fib_alias) * stat->prefixes;
2254
2255 seq_printf(seq, "\tInternal nodes: %u\n\t", stat->tnodes);
2256 bytes += TNODE_SIZE(0) * stat->tnodes;
2257
2258 max = MAX_STAT_DEPTH;
2259 while (max > 0 && stat->nodesizes[max-1] == 0)
2260 max--;
2261
2262 pointers = 0;
2263 for (i = 1; i < max; i++)
2264 if (stat->nodesizes[i] != 0) {
2265 seq_printf(seq, " %u: %u", i, stat->nodesizes[i]);
2266 pointers += (1<<i) * stat->nodesizes[i];
2267 }
2268 seq_putc(seq, '\n');
2269 seq_printf(seq, "\tPointers: %u\n", pointers);
2270
2271 bytes += sizeof(struct key_vector *) * pointers;
2272 seq_printf(seq, "Null ptrs: %u\n", stat->nullpointers);
2273 seq_printf(seq, "Total size: %u kB\n", (bytes + 1023) / 1024);
2274}
2275
2276#ifdef CONFIG_IP_FIB_TRIE_STATS
2277static void trie_show_usage(struct seq_file *seq,
2278 const struct trie_use_stats __percpu *stats)
2279{
2280 struct trie_use_stats s = { 0 };
2281 int cpu;
2282
2283 /* loop through all of the CPUs and gather up the stats */
2284 for_each_possible_cpu(cpu) {
2285 const struct trie_use_stats *pcpu = per_cpu_ptr(stats, cpu);
2286
2287 s.gets += pcpu->gets;
2288 s.backtrack += pcpu->backtrack;
2289 s.semantic_match_passed += pcpu->semantic_match_passed;
2290 s.semantic_match_miss += pcpu->semantic_match_miss;
2291 s.null_node_hit += pcpu->null_node_hit;
2292 s.resize_node_skipped += pcpu->resize_node_skipped;
2293 }
2294
2295 seq_printf(seq, "\nCounters:\n---------\n");
2296 seq_printf(seq, "gets = %u\n", s.gets);
2297 seq_printf(seq, "backtracks = %u\n", s.backtrack);
2298 seq_printf(seq, "semantic match passed = %u\n",
2299 s.semantic_match_passed);
2300 seq_printf(seq, "semantic match miss = %u\n", s.semantic_match_miss);
2301 seq_printf(seq, "null node hit= %u\n", s.null_node_hit);
2302 seq_printf(seq, "skipped node resize = %u\n\n", s.resize_node_skipped);
2303}
2304#endif /* CONFIG_IP_FIB_TRIE_STATS */
2305
2306static void fib_table_print(struct seq_file *seq, struct fib_table *tb)
2307{
2308 if (tb->tb_id == RT_TABLE_LOCAL)
2309 seq_puts(seq, "Local:\n");
2310 else if (tb->tb_id == RT_TABLE_MAIN)
2311 seq_puts(seq, "Main:\n");
2312 else
2313 seq_printf(seq, "Id %d:\n", tb->tb_id);
2314}
2315
2316
2317static int fib_triestat_seq_show(struct seq_file *seq, void *v)
2318{
2319 struct net *net = (struct net *)seq->private;
2320 unsigned int h;
2321
2322 seq_printf(seq,
2323 "Basic info: size of leaf:"
2324 " %zd bytes, size of tnode: %zd bytes.\n",
2325 LEAF_SIZE, TNODE_SIZE(0));
2326
2327 for (h = 0; h < FIB_TABLE_HASHSZ; h++) {
2328 struct hlist_head *head = &net->ipv4.fib_table_hash[h];
2329 struct fib_table *tb;
2330
2331 hlist_for_each_entry_rcu(tb, head, tb_hlist) {
2332 struct trie *t = (struct trie *) tb->tb_data;
2333 struct trie_stat stat;
2334
2335 if (!t)
2336 continue;
2337
2338 fib_table_print(seq, tb);
2339
2340 trie_collect_stats(t, &stat);
2341 trie_show_stats(seq, &stat);
2342#ifdef CONFIG_IP_FIB_TRIE_STATS
2343 trie_show_usage(seq, t->stats);
2344#endif
2345 }
2346 }
2347
2348 return 0;
2349}
2350
2351static int fib_triestat_seq_open(struct inode *inode, struct file *file)
2352{
2353 return single_open_net(inode, file, fib_triestat_seq_show);
2354}
2355
2356static const struct file_operations fib_triestat_fops = {
2357 .open = fib_triestat_seq_open,
2358 .read = seq_read,
2359 .llseek = seq_lseek,
2360 .release = single_release_net,
2361};
2362
2363static struct key_vector *fib_trie_get_idx(struct seq_file *seq, loff_t pos)
2364{
2365 struct fib_trie_iter *iter = seq->private;
2366 struct net *net = seq_file_net(seq);
2367 loff_t idx = 0;
2368 unsigned int h;
2369
2370 for (h = 0; h < FIB_TABLE_HASHSZ; h++) {
2371 struct hlist_head *head = &net->ipv4.fib_table_hash[h];
2372 struct fib_table *tb;
2373
2374 hlist_for_each_entry_rcu(tb, head, tb_hlist) {
2375 struct key_vector *n;
2376
2377 for (n = fib_trie_get_first(iter,
2378 (struct trie *) tb->tb_data);
2379 n; n = fib_trie_get_next(iter))
2380 if (pos == idx++) {
2381 iter->tb = tb;
2382 return n;
2383 }
2384 }
2385 }
2386
2387 return NULL;
2388}
2389
2390static void *fib_trie_seq_start(struct seq_file *seq, loff_t *pos)
2391 __acquires(RCU)
2392{
2393 rcu_read_lock();
2394 return fib_trie_get_idx(seq, *pos);
2395}
2396
2397static void *fib_trie_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2398{
2399 struct fib_trie_iter *iter = seq->private;
2400 struct net *net = seq_file_net(seq);
2401 struct fib_table *tb = iter->tb;
2402 struct hlist_node *tb_node;
2403 unsigned int h;
2404 struct key_vector *n;
2405
2406 ++*pos;
2407 /* next node in same table */
2408 n = fib_trie_get_next(iter);
2409 if (n)
2410 return n;
2411
2412 /* walk rest of this hash chain */
2413 h = tb->tb_id & (FIB_TABLE_HASHSZ - 1);
2414 while ((tb_node = rcu_dereference(hlist_next_rcu(&tb->tb_hlist)))) {
2415 tb = hlist_entry(tb_node, struct fib_table, tb_hlist);
2416 n = fib_trie_get_first(iter, (struct trie *) tb->tb_data);
2417 if (n)
2418 goto found;
2419 }
2420
2421 /* new hash chain */
2422 while (++h < FIB_TABLE_HASHSZ) {
2423 struct hlist_head *head = &net->ipv4.fib_table_hash[h];
2424 hlist_for_each_entry_rcu(tb, head, tb_hlist) {
2425 n = fib_trie_get_first(iter, (struct trie *) tb->tb_data);
2426 if (n)
2427 goto found;
2428 }
2429 }
2430 return NULL;
2431
2432found:
2433 iter->tb = tb;
2434 return n;
2435}
2436
2437static void fib_trie_seq_stop(struct seq_file *seq, void *v)
2438 __releases(RCU)
2439{
2440 rcu_read_unlock();
2441}
2442
2443static void seq_indent(struct seq_file *seq, int n)
2444{
2445 while (n-- > 0)
2446 seq_puts(seq, " ");
2447}
2448
2449static inline const char *rtn_scope(char *buf, size_t len, enum rt_scope_t s)
2450{
2451 switch (s) {
2452 case RT_SCOPE_UNIVERSE: return "universe";
2453 case RT_SCOPE_SITE: return "site";
2454 case RT_SCOPE_LINK: return "link";
2455 case RT_SCOPE_HOST: return "host";
2456 case RT_SCOPE_NOWHERE: return "nowhere";
2457 default:
2458 snprintf(buf, len, "scope=%d", s);
2459 return buf;
2460 }
2461}
2462
2463static const char *const rtn_type_names[__RTN_MAX] = {
2464 [RTN_UNSPEC] = "UNSPEC",
2465 [RTN_UNICAST] = "UNICAST",
2466 [RTN_LOCAL] = "LOCAL",
2467 [RTN_BROADCAST] = "BROADCAST",
2468 [RTN_ANYCAST] = "ANYCAST",
2469 [RTN_MULTICAST] = "MULTICAST",
2470 [RTN_BLACKHOLE] = "BLACKHOLE",
2471 [RTN_UNREACHABLE] = "UNREACHABLE",
2472 [RTN_PROHIBIT] = "PROHIBIT",
2473 [RTN_THROW] = "THROW",
2474 [RTN_NAT] = "NAT",
2475 [RTN_XRESOLVE] = "XRESOLVE",
2476};
2477
2478static inline const char *rtn_type(char *buf, size_t len, unsigned int t)
2479{
2480 if (t < __RTN_MAX && rtn_type_names[t])
2481 return rtn_type_names[t];
2482 snprintf(buf, len, "type %u", t);
2483 return buf;
2484}
2485
2486/* Pretty print the trie */
2487static int fib_trie_seq_show(struct seq_file *seq, void *v)
2488{
2489 const struct fib_trie_iter *iter = seq->private;
2490 struct key_vector *n = v;
2491
2492 if (IS_TRIE(node_parent_rcu(n)))
2493 fib_table_print(seq, iter->tb);
2494
2495 if (IS_TNODE(n)) {
2496 __be32 prf = htonl(n->key);
2497
2498 seq_indent(seq, iter->depth-1);
2499 seq_printf(seq, " +-- %pI4/%zu %u %u %u\n",
2500 &prf, KEYLENGTH - n->pos - n->bits, n->bits,
2501 tn_info(n)->full_children,
2502 tn_info(n)->empty_children);
2503 } else {
2504 __be32 val = htonl(n->key);
2505 struct fib_alias *fa;
2506
2507 seq_indent(seq, iter->depth);
2508 seq_printf(seq, " |-- %pI4\n", &val);
2509
2510 hlist_for_each_entry_rcu(fa, &n->leaf, fa_list) {
2511 char buf1[32], buf2[32];
2512
2513 seq_indent(seq, iter->depth + 1);
2514 seq_printf(seq, " /%zu %s %s",
2515 KEYLENGTH - fa->fa_slen,
2516 rtn_scope(buf1, sizeof(buf1),
2517 fa->fa_info->fib_scope),
2518 rtn_type(buf2, sizeof(buf2),
2519 fa->fa_type));
2520 if (fa->fa_tos)
2521 seq_printf(seq, " tos=%d", fa->fa_tos);
2522 seq_putc(seq, '\n');
2523 }
2524 }
2525
2526 return 0;
2527}
2528
2529static const struct seq_operations fib_trie_seq_ops = {
2530 .start = fib_trie_seq_start,
2531 .next = fib_trie_seq_next,
2532 .stop = fib_trie_seq_stop,
2533 .show = fib_trie_seq_show,
2534};
2535
2536static int fib_trie_seq_open(struct inode *inode, struct file *file)
2537{
2538 return seq_open_net(inode, file, &fib_trie_seq_ops,
2539 sizeof(struct fib_trie_iter));
2540}
2541
2542static const struct file_operations fib_trie_fops = {
2543 .open = fib_trie_seq_open,
2544 .read = seq_read,
2545 .llseek = seq_lseek,
2546 .release = seq_release_net,
2547};
2548
2549struct fib_route_iter {
2550 struct seq_net_private p;
2551 struct fib_table *main_tb;
2552 struct key_vector *tnode;
2553 loff_t pos;
2554 t_key key;
2555};
2556
2557static struct key_vector *fib_route_get_idx(struct fib_route_iter *iter,
2558 loff_t pos)
2559{
2560 struct key_vector *l, **tp = &iter->tnode;
2561 t_key key;
2562
2563 /* use cached location of previously found key */
2564 if (iter->pos > 0 && pos >= iter->pos) {
2565 key = iter->key;
2566 } else {
2567 iter->pos = 1;
2568 key = 0;
2569 }
2570
2571 pos -= iter->pos;
2572
2573 while ((l = leaf_walk_rcu(tp, key)) && (pos-- > 0)) {
2574 key = l->key + 1;
2575 iter->pos++;
2576 l = NULL;
2577
2578 /* handle unlikely case of a key wrap */
2579 if (!key)
2580 break;
2581 }
2582
2583 if (l)
2584 iter->key = l->key; /* remember it */
2585 else
2586 iter->pos = 0; /* forget it */
2587
2588 return l;
2589}
2590
2591static void *fib_route_seq_start(struct seq_file *seq, loff_t *pos)
2592 __acquires(RCU)
2593{
2594 struct fib_route_iter *iter = seq->private;
2595 struct fib_table *tb;
2596 struct trie *t;
2597
2598 rcu_read_lock();
2599
2600 tb = fib_get_table(seq_file_net(seq), RT_TABLE_MAIN);
2601 if (!tb)
2602 return NULL;
2603
2604 iter->main_tb = tb;
2605 t = (struct trie *)tb->tb_data;
2606 iter->tnode = t->kv;
2607
2608 if (*pos != 0)
2609 return fib_route_get_idx(iter, *pos);
2610
2611 iter->pos = 0;
2612 iter->key = KEY_MAX;
2613
2614 return SEQ_START_TOKEN;
2615}
2616
2617static void *fib_route_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2618{
2619 struct fib_route_iter *iter = seq->private;
2620 struct key_vector *l = NULL;
2621 t_key key = iter->key + 1;
2622
2623 ++*pos;
2624
2625 /* only allow key of 0 for start of sequence */
2626 if ((v == SEQ_START_TOKEN) || key)
2627 l = leaf_walk_rcu(&iter->tnode, key);
2628
2629 if (l) {
2630 iter->key = l->key;
2631 iter->pos++;
2632 } else {
2633 iter->pos = 0;
2634 }
2635
2636 return l;
2637}
2638
2639static void fib_route_seq_stop(struct seq_file *seq, void *v)
2640 __releases(RCU)
2641{
2642 rcu_read_unlock();
2643}
2644
2645static unsigned int fib_flag_trans(int type, __be32 mask, const struct fib_info *fi)
2646{
2647 unsigned int flags = 0;
2648
2649 if (type == RTN_UNREACHABLE || type == RTN_PROHIBIT)
2650 flags = RTF_REJECT;
2651 if (fi && fi->fib_nh->nh_gw)
2652 flags |= RTF_GATEWAY;
2653 if (mask == htonl(0xFFFFFFFF))
2654 flags |= RTF_HOST;
2655 flags |= RTF_UP;
2656 return flags;
2657}
2658
2659/*
2660 * This outputs /proc/net/route.
2661 * The format of the file is not supposed to be changed
2662 * and needs to be same as fib_hash output to avoid breaking
2663 * legacy utilities
2664 */
2665static int fib_route_seq_show(struct seq_file *seq, void *v)
2666{
2667 struct fib_route_iter *iter = seq->private;
2668 struct fib_table *tb = iter->main_tb;
2669 struct fib_alias *fa;
2670 struct key_vector *l = v;
2671 __be32 prefix;
2672
2673 if (v == SEQ_START_TOKEN) {
2674 seq_printf(seq, "%-127s\n", "Iface\tDestination\tGateway "
2675 "\tFlags\tRefCnt\tUse\tMetric\tMask\t\tMTU"
2676 "\tWindow\tIRTT");
2677 return 0;
2678 }
2679
2680 prefix = htonl(l->key);
2681
2682 hlist_for_each_entry_rcu(fa, &l->leaf, fa_list) {
2683 const struct fib_info *fi = fa->fa_info;
2684 __be32 mask = inet_make_mask(KEYLENGTH - fa->fa_slen);
2685 unsigned int flags = fib_flag_trans(fa->fa_type, mask, fi);
2686
2687 if ((fa->fa_type == RTN_BROADCAST) ||
2688 (fa->fa_type == RTN_MULTICAST))
2689 continue;
2690
2691 if (fa->tb_id != tb->tb_id)
2692 continue;
2693
2694 seq_setwidth(seq, 127);
2695
2696 if (fi)
2697 seq_printf(seq,
2698 "%s\t%08X\t%08X\t%04X\t%d\t%u\t"
2699 "%d\t%08X\t%d\t%u\t%u",
2700 fi->fib_dev ? fi->fib_dev->name : "*",
2701 prefix,
2702 fi->fib_nh->nh_gw, flags, 0, 0,
2703 fi->fib_priority,
2704 mask,
2705 (fi->fib_advmss ?
2706 fi->fib_advmss + 40 : 0),
2707 fi->fib_window,
2708 fi->fib_rtt >> 3);
2709 else
2710 seq_printf(seq,
2711 "*\t%08X\t%08X\t%04X\t%d\t%u\t"
2712 "%d\t%08X\t%d\t%u\t%u",
2713 prefix, 0, flags, 0, 0, 0,
2714 mask, 0, 0, 0);
2715
2716 seq_pad(seq, '\n');
2717 }
2718
2719 return 0;
2720}
2721
2722static const struct seq_operations fib_route_seq_ops = {
2723 .start = fib_route_seq_start,
2724 .next = fib_route_seq_next,
2725 .stop = fib_route_seq_stop,
2726 .show = fib_route_seq_show,
2727};
2728
2729static int fib_route_seq_open(struct inode *inode, struct file *file)
2730{
2731 return seq_open_net(inode, file, &fib_route_seq_ops,
2732 sizeof(struct fib_route_iter));
2733}
2734
2735static const struct file_operations fib_route_fops = {
2736 .open = fib_route_seq_open,
2737 .read = seq_read,
2738 .llseek = seq_lseek,
2739 .release = seq_release_net,
2740};
2741
2742int __net_init fib_proc_init(struct net *net)
2743{
2744 if (!proc_create("fib_trie", 0444, net->proc_net, &fib_trie_fops))
2745 goto out1;
2746
2747 if (!proc_create("fib_triestat", 0444, net->proc_net,
2748 &fib_triestat_fops))
2749 goto out2;
2750
2751 if (!proc_create("route", 0444, net->proc_net, &fib_route_fops))
2752 goto out3;
2753
2754 return 0;
2755
2756out3:
2757 remove_proc_entry("fib_triestat", net->proc_net);
2758out2:
2759 remove_proc_entry("fib_trie", net->proc_net);
2760out1:
2761 return -ENOMEM;
2762}
2763
2764void __net_exit fib_proc_exit(struct net *net)
2765{
2766 remove_proc_entry("fib_trie", net->proc_net);
2767 remove_proc_entry("fib_triestat", net->proc_net);
2768 remove_proc_entry("route", net->proc_net);
2769}
2770
2771#endif /* CONFIG_PROC_FS */
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 *
4 * Robert Olsson <robert.olsson@its.uu.se> Uppsala Universitet
5 * & Swedish University of Agricultural Sciences.
6 *
7 * Jens Laas <jens.laas@data.slu.se> Swedish University of
8 * Agricultural Sciences.
9 *
10 * Hans Liss <hans.liss@its.uu.se> Uppsala Universitet
11 *
12 * This work is based on the LPC-trie which is originally described in:
13 *
14 * An experimental study of compression methods for dynamic tries
15 * Stefan Nilsson and Matti Tikkanen. Algorithmica, 33(1):19-33, 2002.
16 * https://www.csc.kth.se/~snilsson/software/dyntrie2/
17 *
18 * IP-address lookup using LC-tries. Stefan Nilsson and Gunnar Karlsson
19 * IEEE Journal on Selected Areas in Communications, 17(6):1083-1092, June 1999
20 *
21 * Code from fib_hash has been reused which includes the following header:
22 *
23 * INET An implementation of the TCP/IP protocol suite for the LINUX
24 * operating system. INET is implemented using the BSD Socket
25 * interface as the means of communication with the user level.
26 *
27 * IPv4 FIB: lookup engine and maintenance routines.
28 *
29 * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
30 *
31 * Substantial contributions to this work comes from:
32 *
33 * David S. Miller, <davem@davemloft.net>
34 * Stephen Hemminger <shemminger@osdl.org>
35 * Paul E. McKenney <paulmck@us.ibm.com>
36 * Patrick McHardy <kaber@trash.net>
37 */
38#include <linux/cache.h>
39#include <linux/uaccess.h>
40#include <linux/bitops.h>
41#include <linux/types.h>
42#include <linux/kernel.h>
43#include <linux/mm.h>
44#include <linux/string.h>
45#include <linux/socket.h>
46#include <linux/sockios.h>
47#include <linux/errno.h>
48#include <linux/in.h>
49#include <linux/inet.h>
50#include <linux/inetdevice.h>
51#include <linux/netdevice.h>
52#include <linux/if_arp.h>
53#include <linux/proc_fs.h>
54#include <linux/rcupdate.h>
55#include <linux/rcupdate_wait.h>
56#include <linux/skbuff.h>
57#include <linux/netlink.h>
58#include <linux/init.h>
59#include <linux/list.h>
60#include <linux/slab.h>
61#include <linux/export.h>
62#include <linux/vmalloc.h>
63#include <linux/notifier.h>
64#include <net/net_namespace.h>
65#include <net/inet_dscp.h>
66#include <net/ip.h>
67#include <net/protocol.h>
68#include <net/route.h>
69#include <net/tcp.h>
70#include <net/sock.h>
71#include <net/ip_fib.h>
72#include <net/fib_notifier.h>
73#include <trace/events/fib.h>
74#include "fib_lookup.h"
75
76static int call_fib_entry_notifier(struct notifier_block *nb,
77 enum fib_event_type event_type, u32 dst,
78 int dst_len, struct fib_alias *fa,
79 struct netlink_ext_ack *extack)
80{
81 struct fib_entry_notifier_info info = {
82 .info.extack = extack,
83 .dst = dst,
84 .dst_len = dst_len,
85 .fi = fa->fa_info,
86 .dscp = fa->fa_dscp,
87 .type = fa->fa_type,
88 .tb_id = fa->tb_id,
89 };
90 return call_fib4_notifier(nb, event_type, &info.info);
91}
92
93static int call_fib_entry_notifiers(struct net *net,
94 enum fib_event_type event_type, u32 dst,
95 int dst_len, struct fib_alias *fa,
96 struct netlink_ext_ack *extack)
97{
98 struct fib_entry_notifier_info info = {
99 .info.extack = extack,
100 .dst = dst,
101 .dst_len = dst_len,
102 .fi = fa->fa_info,
103 .dscp = fa->fa_dscp,
104 .type = fa->fa_type,
105 .tb_id = fa->tb_id,
106 };
107 return call_fib4_notifiers(net, event_type, &info.info);
108}
109
110#define MAX_STAT_DEPTH 32
111
112#define KEYLENGTH (8*sizeof(t_key))
113#define KEY_MAX ((t_key)~0)
114
115typedef unsigned int t_key;
116
117#define IS_TRIE(n) ((n)->pos >= KEYLENGTH)
118#define IS_TNODE(n) ((n)->bits)
119#define IS_LEAF(n) (!(n)->bits)
120
121struct key_vector {
122 t_key key;
123 unsigned char pos; /* 2log(KEYLENGTH) bits needed */
124 unsigned char bits; /* 2log(KEYLENGTH) bits needed */
125 unsigned char slen;
126 union {
127 /* This list pointer if valid if (pos | bits) == 0 (LEAF) */
128 struct hlist_head leaf;
129 /* This array is valid if (pos | bits) > 0 (TNODE) */
130 DECLARE_FLEX_ARRAY(struct key_vector __rcu *, tnode);
131 };
132};
133
134struct tnode {
135 struct rcu_head rcu;
136 t_key empty_children; /* KEYLENGTH bits needed */
137 t_key full_children; /* KEYLENGTH bits needed */
138 struct key_vector __rcu *parent;
139 struct key_vector kv[1];
140#define tn_bits kv[0].bits
141};
142
143#define TNODE_SIZE(n) offsetof(struct tnode, kv[0].tnode[n])
144#define LEAF_SIZE TNODE_SIZE(1)
145
146#ifdef CONFIG_IP_FIB_TRIE_STATS
147struct trie_use_stats {
148 unsigned int gets;
149 unsigned int backtrack;
150 unsigned int semantic_match_passed;
151 unsigned int semantic_match_miss;
152 unsigned int null_node_hit;
153 unsigned int resize_node_skipped;
154};
155#endif
156
157struct trie_stat {
158 unsigned int totdepth;
159 unsigned int maxdepth;
160 unsigned int tnodes;
161 unsigned int leaves;
162 unsigned int nullpointers;
163 unsigned int prefixes;
164 unsigned int nodesizes[MAX_STAT_DEPTH];
165};
166
167struct trie {
168 struct key_vector kv[1];
169#ifdef CONFIG_IP_FIB_TRIE_STATS
170 struct trie_use_stats __percpu *stats;
171#endif
172};
173
174static struct key_vector *resize(struct trie *t, struct key_vector *tn);
175static unsigned int tnode_free_size;
176
177/*
178 * synchronize_rcu after call_rcu for outstanding dirty memory; it should be
179 * especially useful before resizing the root node with PREEMPT_NONE configs;
180 * the value was obtained experimentally, aiming to avoid visible slowdown.
181 */
182unsigned int sysctl_fib_sync_mem = 512 * 1024;
183unsigned int sysctl_fib_sync_mem_min = 64 * 1024;
184unsigned int sysctl_fib_sync_mem_max = 64 * 1024 * 1024;
185
186static struct kmem_cache *fn_alias_kmem __ro_after_init;
187static struct kmem_cache *trie_leaf_kmem __ro_after_init;
188
189static inline struct tnode *tn_info(struct key_vector *kv)
190{
191 return container_of(kv, struct tnode, kv[0]);
192}
193
194/* caller must hold RTNL */
195#define node_parent(tn) rtnl_dereference(tn_info(tn)->parent)
196#define get_child(tn, i) rtnl_dereference((tn)->tnode[i])
197
198/* caller must hold RCU read lock or RTNL */
199#define node_parent_rcu(tn) rcu_dereference_rtnl(tn_info(tn)->parent)
200#define get_child_rcu(tn, i) rcu_dereference_rtnl((tn)->tnode[i])
201
202/* wrapper for rcu_assign_pointer */
203static inline void node_set_parent(struct key_vector *n, struct key_vector *tp)
204{
205 if (n)
206 rcu_assign_pointer(tn_info(n)->parent, tp);
207}
208
209#define NODE_INIT_PARENT(n, p) RCU_INIT_POINTER(tn_info(n)->parent, p)
210
211/* This provides us with the number of children in this node, in the case of a
212 * leaf this will return 0 meaning none of the children are accessible.
213 */
214static inline unsigned long child_length(const struct key_vector *tn)
215{
216 return (1ul << tn->bits) & ~(1ul);
217}
218
219#define get_cindex(key, kv) (((key) ^ (kv)->key) >> (kv)->pos)
220
221static inline unsigned long get_index(t_key key, struct key_vector *kv)
222{
223 unsigned long index = key ^ kv->key;
224
225 if ((BITS_PER_LONG <= KEYLENGTH) && (KEYLENGTH == kv->pos))
226 return 0;
227
228 return index >> kv->pos;
229}
230
231/* To understand this stuff, an understanding of keys and all their bits is
232 * necessary. Every node in the trie has a key associated with it, but not
233 * all of the bits in that key are significant.
234 *
235 * Consider a node 'n' and its parent 'tp'.
236 *
237 * If n is a leaf, every bit in its key is significant. Its presence is
238 * necessitated by path compression, since during a tree traversal (when
239 * searching for a leaf - unless we are doing an insertion) we will completely
240 * ignore all skipped bits we encounter. Thus we need to verify, at the end of
241 * a potentially successful search, that we have indeed been walking the
242 * correct key path.
243 *
244 * Note that we can never "miss" the correct key in the tree if present by
245 * following the wrong path. Path compression ensures that segments of the key
246 * that are the same for all keys with a given prefix are skipped, but the
247 * skipped part *is* identical for each node in the subtrie below the skipped
248 * bit! trie_insert() in this implementation takes care of that.
249 *
250 * if n is an internal node - a 'tnode' here, the various parts of its key
251 * have many different meanings.
252 *
253 * Example:
254 * _________________________________________________________________
255 * | i | i | i | i | i | i | i | N | N | N | S | S | S | S | S | C |
256 * -----------------------------------------------------------------
257 * 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16
258 *
259 * _________________________________________________________________
260 * | C | C | C | u | u | u | u | u | u | u | u | u | u | u | u | u |
261 * -----------------------------------------------------------------
262 * 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
263 *
264 * tp->pos = 22
265 * tp->bits = 3
266 * n->pos = 13
267 * n->bits = 4
268 *
269 * First, let's just ignore the bits that come before the parent tp, that is
270 * the bits from (tp->pos + tp->bits) to 31. They are *known* but at this
271 * point we do not use them for anything.
272 *
273 * The bits from (tp->pos) to (tp->pos + tp->bits - 1) - "N", above - are the
274 * index into the parent's child array. That is, they will be used to find
275 * 'n' among tp's children.
276 *
277 * The bits from (n->pos + n->bits) to (tp->pos - 1) - "S" - are skipped bits
278 * for the node n.
279 *
280 * All the bits we have seen so far are significant to the node n. The rest
281 * of the bits are really not needed or indeed known in n->key.
282 *
283 * The bits from (n->pos) to (n->pos + n->bits - 1) - "C" - are the index into
284 * n's child array, and will of course be different for each child.
285 *
286 * The rest of the bits, from 0 to (n->pos -1) - "u" - are completely unknown
287 * at this point.
288 */
289
290static const int halve_threshold = 25;
291static const int inflate_threshold = 50;
292static const int halve_threshold_root = 15;
293static const int inflate_threshold_root = 30;
294
295static void __alias_free_mem(struct rcu_head *head)
296{
297 struct fib_alias *fa = container_of(head, struct fib_alias, rcu);
298 kmem_cache_free(fn_alias_kmem, fa);
299}
300
301static inline void alias_free_mem_rcu(struct fib_alias *fa)
302{
303 call_rcu(&fa->rcu, __alias_free_mem);
304}
305
306#define TNODE_VMALLOC_MAX \
307 ilog2((SIZE_MAX - TNODE_SIZE(0)) / sizeof(struct key_vector *))
308
309static void __node_free_rcu(struct rcu_head *head)
310{
311 struct tnode *n = container_of(head, struct tnode, rcu);
312
313 if (!n->tn_bits)
314 kmem_cache_free(trie_leaf_kmem, n);
315 else
316 kvfree(n);
317}
318
319#define node_free(n) call_rcu(&tn_info(n)->rcu, __node_free_rcu)
320
321static struct tnode *tnode_alloc(int bits)
322{
323 size_t size;
324
325 /* verify bits is within bounds */
326 if (bits > TNODE_VMALLOC_MAX)
327 return NULL;
328
329 /* determine size and verify it is non-zero and didn't overflow */
330 size = TNODE_SIZE(1ul << bits);
331
332 if (size <= PAGE_SIZE)
333 return kzalloc(size, GFP_KERNEL);
334 else
335 return vzalloc(size);
336}
337
338static inline void empty_child_inc(struct key_vector *n)
339{
340 tn_info(n)->empty_children++;
341
342 if (!tn_info(n)->empty_children)
343 tn_info(n)->full_children++;
344}
345
346static inline void empty_child_dec(struct key_vector *n)
347{
348 if (!tn_info(n)->empty_children)
349 tn_info(n)->full_children--;
350
351 tn_info(n)->empty_children--;
352}
353
354static struct key_vector *leaf_new(t_key key, struct fib_alias *fa)
355{
356 struct key_vector *l;
357 struct tnode *kv;
358
359 kv = kmem_cache_alloc(trie_leaf_kmem, GFP_KERNEL);
360 if (!kv)
361 return NULL;
362
363 /* initialize key vector */
364 l = kv->kv;
365 l->key = key;
366 l->pos = 0;
367 l->bits = 0;
368 l->slen = fa->fa_slen;
369
370 /* link leaf to fib alias */
371 INIT_HLIST_HEAD(&l->leaf);
372 hlist_add_head(&fa->fa_list, &l->leaf);
373
374 return l;
375}
376
377static struct key_vector *tnode_new(t_key key, int pos, int bits)
378{
379 unsigned int shift = pos + bits;
380 struct key_vector *tn;
381 struct tnode *tnode;
382
383 /* verify bits and pos their msb bits clear and values are valid */
384 BUG_ON(!bits || (shift > KEYLENGTH));
385
386 tnode = tnode_alloc(bits);
387 if (!tnode)
388 return NULL;
389
390 pr_debug("AT %p s=%zu %zu\n", tnode, TNODE_SIZE(0),
391 sizeof(struct key_vector *) << bits);
392
393 if (bits == KEYLENGTH)
394 tnode->full_children = 1;
395 else
396 tnode->empty_children = 1ul << bits;
397
398 tn = tnode->kv;
399 tn->key = (shift < KEYLENGTH) ? (key >> shift) << shift : 0;
400 tn->pos = pos;
401 tn->bits = bits;
402 tn->slen = pos;
403
404 return tn;
405}
406
407/* Check whether a tnode 'n' is "full", i.e. it is an internal node
408 * and no bits are skipped. See discussion in dyntree paper p. 6
409 */
410static inline int tnode_full(struct key_vector *tn, struct key_vector *n)
411{
412 return n && ((n->pos + n->bits) == tn->pos) && IS_TNODE(n);
413}
414
415/* Add a child at position i overwriting the old value.
416 * Update the value of full_children and empty_children.
417 */
418static void put_child(struct key_vector *tn, unsigned long i,
419 struct key_vector *n)
420{
421 struct key_vector *chi = get_child(tn, i);
422 int isfull, wasfull;
423
424 BUG_ON(i >= child_length(tn));
425
426 /* update emptyChildren, overflow into fullChildren */
427 if (!n && chi)
428 empty_child_inc(tn);
429 if (n && !chi)
430 empty_child_dec(tn);
431
432 /* update fullChildren */
433 wasfull = tnode_full(tn, chi);
434 isfull = tnode_full(tn, n);
435
436 if (wasfull && !isfull)
437 tn_info(tn)->full_children--;
438 else if (!wasfull && isfull)
439 tn_info(tn)->full_children++;
440
441 if (n && (tn->slen < n->slen))
442 tn->slen = n->slen;
443
444 rcu_assign_pointer(tn->tnode[i], n);
445}
446
447static void update_children(struct key_vector *tn)
448{
449 unsigned long i;
450
451 /* update all of the child parent pointers */
452 for (i = child_length(tn); i;) {
453 struct key_vector *inode = get_child(tn, --i);
454
455 if (!inode)
456 continue;
457
458 /* Either update the children of a tnode that
459 * already belongs to us or update the child
460 * to point to ourselves.
461 */
462 if (node_parent(inode) == tn)
463 update_children(inode);
464 else
465 node_set_parent(inode, tn);
466 }
467}
468
469static inline void put_child_root(struct key_vector *tp, t_key key,
470 struct key_vector *n)
471{
472 if (IS_TRIE(tp))
473 rcu_assign_pointer(tp->tnode[0], n);
474 else
475 put_child(tp, get_index(key, tp), n);
476}
477
478static inline void tnode_free_init(struct key_vector *tn)
479{
480 tn_info(tn)->rcu.next = NULL;
481}
482
483static inline void tnode_free_append(struct key_vector *tn,
484 struct key_vector *n)
485{
486 tn_info(n)->rcu.next = tn_info(tn)->rcu.next;
487 tn_info(tn)->rcu.next = &tn_info(n)->rcu;
488}
489
490static void tnode_free(struct key_vector *tn)
491{
492 struct callback_head *head = &tn_info(tn)->rcu;
493
494 while (head) {
495 head = head->next;
496 tnode_free_size += TNODE_SIZE(1ul << tn->bits);
497 node_free(tn);
498
499 tn = container_of(head, struct tnode, rcu)->kv;
500 }
501
502 if (tnode_free_size >= READ_ONCE(sysctl_fib_sync_mem)) {
503 tnode_free_size = 0;
504 synchronize_net();
505 }
506}
507
508static struct key_vector *replace(struct trie *t,
509 struct key_vector *oldtnode,
510 struct key_vector *tn)
511{
512 struct key_vector *tp = node_parent(oldtnode);
513 unsigned long i;
514
515 /* setup the parent pointer out of and back into this node */
516 NODE_INIT_PARENT(tn, tp);
517 put_child_root(tp, tn->key, tn);
518
519 /* update all of the child parent pointers */
520 update_children(tn);
521
522 /* all pointers should be clean so we are done */
523 tnode_free(oldtnode);
524
525 /* resize children now that oldtnode is freed */
526 for (i = child_length(tn); i;) {
527 struct key_vector *inode = get_child(tn, --i);
528
529 /* resize child node */
530 if (tnode_full(tn, inode))
531 tn = resize(t, inode);
532 }
533
534 return tp;
535}
536
537static struct key_vector *inflate(struct trie *t,
538 struct key_vector *oldtnode)
539{
540 struct key_vector *tn;
541 unsigned long i;
542 t_key m;
543
544 pr_debug("In inflate\n");
545
546 tn = tnode_new(oldtnode->key, oldtnode->pos - 1, oldtnode->bits + 1);
547 if (!tn)
548 goto notnode;
549
550 /* prepare oldtnode to be freed */
551 tnode_free_init(oldtnode);
552
553 /* Assemble all of the pointers in our cluster, in this case that
554 * represents all of the pointers out of our allocated nodes that
555 * point to existing tnodes and the links between our allocated
556 * nodes.
557 */
558 for (i = child_length(oldtnode), m = 1u << tn->pos; i;) {
559 struct key_vector *inode = get_child(oldtnode, --i);
560 struct key_vector *node0, *node1;
561 unsigned long j, k;
562
563 /* An empty child */
564 if (!inode)
565 continue;
566
567 /* A leaf or an internal node with skipped bits */
568 if (!tnode_full(oldtnode, inode)) {
569 put_child(tn, get_index(inode->key, tn), inode);
570 continue;
571 }
572
573 /* drop the node in the old tnode free list */
574 tnode_free_append(oldtnode, inode);
575
576 /* An internal node with two children */
577 if (inode->bits == 1) {
578 put_child(tn, 2 * i + 1, get_child(inode, 1));
579 put_child(tn, 2 * i, get_child(inode, 0));
580 continue;
581 }
582
583 /* We will replace this node 'inode' with two new
584 * ones, 'node0' and 'node1', each with half of the
585 * original children. The two new nodes will have
586 * a position one bit further down the key and this
587 * means that the "significant" part of their keys
588 * (see the discussion near the top of this file)
589 * will differ by one bit, which will be "0" in
590 * node0's key and "1" in node1's key. Since we are
591 * moving the key position by one step, the bit that
592 * we are moving away from - the bit at position
593 * (tn->pos) - is the one that will differ between
594 * node0 and node1. So... we synthesize that bit in the
595 * two new keys.
596 */
597 node1 = tnode_new(inode->key | m, inode->pos, inode->bits - 1);
598 if (!node1)
599 goto nomem;
600 node0 = tnode_new(inode->key, inode->pos, inode->bits - 1);
601
602 tnode_free_append(tn, node1);
603 if (!node0)
604 goto nomem;
605 tnode_free_append(tn, node0);
606
607 /* populate child pointers in new nodes */
608 for (k = child_length(inode), j = k / 2; j;) {
609 put_child(node1, --j, get_child(inode, --k));
610 put_child(node0, j, get_child(inode, j));
611 put_child(node1, --j, get_child(inode, --k));
612 put_child(node0, j, get_child(inode, j));
613 }
614
615 /* link new nodes to parent */
616 NODE_INIT_PARENT(node1, tn);
617 NODE_INIT_PARENT(node0, tn);
618
619 /* link parent to nodes */
620 put_child(tn, 2 * i + 1, node1);
621 put_child(tn, 2 * i, node0);
622 }
623
624 /* setup the parent pointers into and out of this node */
625 return replace(t, oldtnode, tn);
626nomem:
627 /* all pointers should be clean so we are done */
628 tnode_free(tn);
629notnode:
630 return NULL;
631}
632
633static struct key_vector *halve(struct trie *t,
634 struct key_vector *oldtnode)
635{
636 struct key_vector *tn;
637 unsigned long i;
638
639 pr_debug("In halve\n");
640
641 tn = tnode_new(oldtnode->key, oldtnode->pos + 1, oldtnode->bits - 1);
642 if (!tn)
643 goto notnode;
644
645 /* prepare oldtnode to be freed */
646 tnode_free_init(oldtnode);
647
648 /* Assemble all of the pointers in our cluster, in this case that
649 * represents all of the pointers out of our allocated nodes that
650 * point to existing tnodes and the links between our allocated
651 * nodes.
652 */
653 for (i = child_length(oldtnode); i;) {
654 struct key_vector *node1 = get_child(oldtnode, --i);
655 struct key_vector *node0 = get_child(oldtnode, --i);
656 struct key_vector *inode;
657
658 /* At least one of the children is empty */
659 if (!node1 || !node0) {
660 put_child(tn, i / 2, node1 ? : node0);
661 continue;
662 }
663
664 /* Two nonempty children */
665 inode = tnode_new(node0->key, oldtnode->pos, 1);
666 if (!inode)
667 goto nomem;
668 tnode_free_append(tn, inode);
669
670 /* initialize pointers out of node */
671 put_child(inode, 1, node1);
672 put_child(inode, 0, node0);
673 NODE_INIT_PARENT(inode, tn);
674
675 /* link parent to node */
676 put_child(tn, i / 2, inode);
677 }
678
679 /* setup the parent pointers into and out of this node */
680 return replace(t, oldtnode, tn);
681nomem:
682 /* all pointers should be clean so we are done */
683 tnode_free(tn);
684notnode:
685 return NULL;
686}
687
688static struct key_vector *collapse(struct trie *t,
689 struct key_vector *oldtnode)
690{
691 struct key_vector *n, *tp;
692 unsigned long i;
693
694 /* scan the tnode looking for that one child that might still exist */
695 for (n = NULL, i = child_length(oldtnode); !n && i;)
696 n = get_child(oldtnode, --i);
697
698 /* compress one level */
699 tp = node_parent(oldtnode);
700 put_child_root(tp, oldtnode->key, n);
701 node_set_parent(n, tp);
702
703 /* drop dead node */
704 node_free(oldtnode);
705
706 return tp;
707}
708
709static unsigned char update_suffix(struct key_vector *tn)
710{
711 unsigned char slen = tn->pos;
712 unsigned long stride, i;
713 unsigned char slen_max;
714
715 /* only vector 0 can have a suffix length greater than or equal to
716 * tn->pos + tn->bits, the second highest node will have a suffix
717 * length at most of tn->pos + tn->bits - 1
718 */
719 slen_max = min_t(unsigned char, tn->pos + tn->bits - 1, tn->slen);
720
721 /* search though the list of children looking for nodes that might
722 * have a suffix greater than the one we currently have. This is
723 * why we start with a stride of 2 since a stride of 1 would
724 * represent the nodes with suffix length equal to tn->pos
725 */
726 for (i = 0, stride = 0x2ul ; i < child_length(tn); i += stride) {
727 struct key_vector *n = get_child(tn, i);
728
729 if (!n || (n->slen <= slen))
730 continue;
731
732 /* update stride and slen based on new value */
733 stride <<= (n->slen - slen);
734 slen = n->slen;
735 i &= ~(stride - 1);
736
737 /* stop searching if we have hit the maximum possible value */
738 if (slen >= slen_max)
739 break;
740 }
741
742 tn->slen = slen;
743
744 return slen;
745}
746
747/* From "Implementing a dynamic compressed trie" by Stefan Nilsson of
748 * the Helsinki University of Technology and Matti Tikkanen of Nokia
749 * Telecommunications, page 6:
750 * "A node is doubled if the ratio of non-empty children to all
751 * children in the *doubled* node is at least 'high'."
752 *
753 * 'high' in this instance is the variable 'inflate_threshold'. It
754 * is expressed as a percentage, so we multiply it with
755 * child_length() and instead of multiplying by 2 (since the
756 * child array will be doubled by inflate()) and multiplying
757 * the left-hand side by 100 (to handle the percentage thing) we
758 * multiply the left-hand side by 50.
759 *
760 * The left-hand side may look a bit weird: child_length(tn)
761 * - tn->empty_children is of course the number of non-null children
762 * in the current node. tn->full_children is the number of "full"
763 * children, that is non-null tnodes with a skip value of 0.
764 * All of those will be doubled in the resulting inflated tnode, so
765 * we just count them one extra time here.
766 *
767 * A clearer way to write this would be:
768 *
769 * to_be_doubled = tn->full_children;
770 * not_to_be_doubled = child_length(tn) - tn->empty_children -
771 * tn->full_children;
772 *
773 * new_child_length = child_length(tn) * 2;
774 *
775 * new_fill_factor = 100 * (not_to_be_doubled + 2*to_be_doubled) /
776 * new_child_length;
777 * if (new_fill_factor >= inflate_threshold)
778 *
779 * ...and so on, tho it would mess up the while () loop.
780 *
781 * anyway,
782 * 100 * (not_to_be_doubled + 2*to_be_doubled) / new_child_length >=
783 * inflate_threshold
784 *
785 * avoid a division:
786 * 100 * (not_to_be_doubled + 2*to_be_doubled) >=
787 * inflate_threshold * new_child_length
788 *
789 * expand not_to_be_doubled and to_be_doubled, and shorten:
790 * 100 * (child_length(tn) - tn->empty_children +
791 * tn->full_children) >= inflate_threshold * new_child_length
792 *
793 * expand new_child_length:
794 * 100 * (child_length(tn) - tn->empty_children +
795 * tn->full_children) >=
796 * inflate_threshold * child_length(tn) * 2
797 *
798 * shorten again:
799 * 50 * (tn->full_children + child_length(tn) -
800 * tn->empty_children) >= inflate_threshold *
801 * child_length(tn)
802 *
803 */
804static inline bool should_inflate(struct key_vector *tp, struct key_vector *tn)
805{
806 unsigned long used = child_length(tn);
807 unsigned long threshold = used;
808
809 /* Keep root node larger */
810 threshold *= IS_TRIE(tp) ? inflate_threshold_root : inflate_threshold;
811 used -= tn_info(tn)->empty_children;
812 used += tn_info(tn)->full_children;
813
814 /* if bits == KEYLENGTH then pos = 0, and will fail below */
815
816 return (used > 1) && tn->pos && ((50 * used) >= threshold);
817}
818
819static inline bool should_halve(struct key_vector *tp, struct key_vector *tn)
820{
821 unsigned long used = child_length(tn);
822 unsigned long threshold = used;
823
824 /* Keep root node larger */
825 threshold *= IS_TRIE(tp) ? halve_threshold_root : halve_threshold;
826 used -= tn_info(tn)->empty_children;
827
828 /* if bits == KEYLENGTH then used = 100% on wrap, and will fail below */
829
830 return (used > 1) && (tn->bits > 1) && ((100 * used) < threshold);
831}
832
833static inline bool should_collapse(struct key_vector *tn)
834{
835 unsigned long used = child_length(tn);
836
837 used -= tn_info(tn)->empty_children;
838
839 /* account for bits == KEYLENGTH case */
840 if ((tn->bits == KEYLENGTH) && tn_info(tn)->full_children)
841 used -= KEY_MAX;
842
843 /* One child or none, time to drop us from the trie */
844 return used < 2;
845}
846
847#define MAX_WORK 10
848static struct key_vector *resize(struct trie *t, struct key_vector *tn)
849{
850#ifdef CONFIG_IP_FIB_TRIE_STATS
851 struct trie_use_stats __percpu *stats = t->stats;
852#endif
853 struct key_vector *tp = node_parent(tn);
854 unsigned long cindex = get_index(tn->key, tp);
855 int max_work = MAX_WORK;
856
857 pr_debug("In tnode_resize %p inflate_threshold=%d threshold=%d\n",
858 tn, inflate_threshold, halve_threshold);
859
860 /* track the tnode via the pointer from the parent instead of
861 * doing it ourselves. This way we can let RCU fully do its
862 * thing without us interfering
863 */
864 BUG_ON(tn != get_child(tp, cindex));
865
866 /* Double as long as the resulting node has a number of
867 * nonempty nodes that are above the threshold.
868 */
869 while (should_inflate(tp, tn) && max_work) {
870 tp = inflate(t, tn);
871 if (!tp) {
872#ifdef CONFIG_IP_FIB_TRIE_STATS
873 this_cpu_inc(stats->resize_node_skipped);
874#endif
875 break;
876 }
877
878 max_work--;
879 tn = get_child(tp, cindex);
880 }
881
882 /* update parent in case inflate failed */
883 tp = node_parent(tn);
884
885 /* Return if at least one inflate is run */
886 if (max_work != MAX_WORK)
887 return tp;
888
889 /* Halve as long as the number of empty children in this
890 * node is above threshold.
891 */
892 while (should_halve(tp, tn) && max_work) {
893 tp = halve(t, tn);
894 if (!tp) {
895#ifdef CONFIG_IP_FIB_TRIE_STATS
896 this_cpu_inc(stats->resize_node_skipped);
897#endif
898 break;
899 }
900
901 max_work--;
902 tn = get_child(tp, cindex);
903 }
904
905 /* Only one child remains */
906 if (should_collapse(tn))
907 return collapse(t, tn);
908
909 /* update parent in case halve failed */
910 return node_parent(tn);
911}
912
913static void node_pull_suffix(struct key_vector *tn, unsigned char slen)
914{
915 unsigned char node_slen = tn->slen;
916
917 while ((node_slen > tn->pos) && (node_slen > slen)) {
918 slen = update_suffix(tn);
919 if (node_slen == slen)
920 break;
921
922 tn = node_parent(tn);
923 node_slen = tn->slen;
924 }
925}
926
927static void node_push_suffix(struct key_vector *tn, unsigned char slen)
928{
929 while (tn->slen < slen) {
930 tn->slen = slen;
931 tn = node_parent(tn);
932 }
933}
934
935/* rcu_read_lock needs to be hold by caller from readside */
936static struct key_vector *fib_find_node(struct trie *t,
937 struct key_vector **tp, u32 key)
938{
939 struct key_vector *pn, *n = t->kv;
940 unsigned long index = 0;
941
942 do {
943 pn = n;
944 n = get_child_rcu(n, index);
945
946 if (!n)
947 break;
948
949 index = get_cindex(key, n);
950
951 /* This bit of code is a bit tricky but it combines multiple
952 * checks into a single check. The prefix consists of the
953 * prefix plus zeros for the bits in the cindex. The index
954 * is the difference between the key and this value. From
955 * this we can actually derive several pieces of data.
956 * if (index >= (1ul << bits))
957 * we have a mismatch in skip bits and failed
958 * else
959 * we know the value is cindex
960 *
961 * This check is safe even if bits == KEYLENGTH due to the
962 * fact that we can only allocate a node with 32 bits if a
963 * long is greater than 32 bits.
964 */
965 if (index >= (1ul << n->bits)) {
966 n = NULL;
967 break;
968 }
969
970 /* keep searching until we find a perfect match leaf or NULL */
971 } while (IS_TNODE(n));
972
973 *tp = pn;
974
975 return n;
976}
977
978/* Return the first fib alias matching DSCP with
979 * priority less than or equal to PRIO.
980 * If 'find_first' is set, return the first matching
981 * fib alias, regardless of DSCP and priority.
982 */
983static struct fib_alias *fib_find_alias(struct hlist_head *fah, u8 slen,
984 dscp_t dscp, u32 prio, u32 tb_id,
985 bool find_first)
986{
987 struct fib_alias *fa;
988
989 if (!fah)
990 return NULL;
991
992 hlist_for_each_entry(fa, fah, fa_list) {
993 /* Avoid Sparse warning when using dscp_t in inequalities */
994 u8 __fa_dscp = inet_dscp_to_dsfield(fa->fa_dscp);
995 u8 __dscp = inet_dscp_to_dsfield(dscp);
996
997 if (fa->fa_slen < slen)
998 continue;
999 if (fa->fa_slen != slen)
1000 break;
1001 if (fa->tb_id > tb_id)
1002 continue;
1003 if (fa->tb_id != tb_id)
1004 break;
1005 if (find_first)
1006 return fa;
1007 if (__fa_dscp > __dscp)
1008 continue;
1009 if (fa->fa_info->fib_priority >= prio || __fa_dscp < __dscp)
1010 return fa;
1011 }
1012
1013 return NULL;
1014}
1015
1016static struct fib_alias *
1017fib_find_matching_alias(struct net *net, const struct fib_rt_info *fri)
1018{
1019 u8 slen = KEYLENGTH - fri->dst_len;
1020 struct key_vector *l, *tp;
1021 struct fib_table *tb;
1022 struct fib_alias *fa;
1023 struct trie *t;
1024
1025 tb = fib_get_table(net, fri->tb_id);
1026 if (!tb)
1027 return NULL;
1028
1029 t = (struct trie *)tb->tb_data;
1030 l = fib_find_node(t, &tp, be32_to_cpu(fri->dst));
1031 if (!l)
1032 return NULL;
1033
1034 hlist_for_each_entry_rcu(fa, &l->leaf, fa_list) {
1035 if (fa->fa_slen == slen && fa->tb_id == fri->tb_id &&
1036 fa->fa_dscp == fri->dscp && fa->fa_info == fri->fi &&
1037 fa->fa_type == fri->type)
1038 return fa;
1039 }
1040
1041 return NULL;
1042}
1043
1044void fib_alias_hw_flags_set(struct net *net, const struct fib_rt_info *fri)
1045{
1046 u8 fib_notify_on_flag_change;
1047 struct fib_alias *fa_match;
1048 struct sk_buff *skb;
1049 int err;
1050
1051 rcu_read_lock();
1052
1053 fa_match = fib_find_matching_alias(net, fri);
1054 if (!fa_match)
1055 goto out;
1056
1057 /* These are paired with the WRITE_ONCE() happening in this function.
1058 * The reason is that we are only protected by RCU at this point.
1059 */
1060 if (READ_ONCE(fa_match->offload) == fri->offload &&
1061 READ_ONCE(fa_match->trap) == fri->trap &&
1062 READ_ONCE(fa_match->offload_failed) == fri->offload_failed)
1063 goto out;
1064
1065 WRITE_ONCE(fa_match->offload, fri->offload);
1066 WRITE_ONCE(fa_match->trap, fri->trap);
1067
1068 fib_notify_on_flag_change = READ_ONCE(net->ipv4.sysctl_fib_notify_on_flag_change);
1069
1070 /* 2 means send notifications only if offload_failed was changed. */
1071 if (fib_notify_on_flag_change == 2 &&
1072 READ_ONCE(fa_match->offload_failed) == fri->offload_failed)
1073 goto out;
1074
1075 WRITE_ONCE(fa_match->offload_failed, fri->offload_failed);
1076
1077 if (!fib_notify_on_flag_change)
1078 goto out;
1079
1080 skb = nlmsg_new(fib_nlmsg_size(fa_match->fa_info), GFP_ATOMIC);
1081 if (!skb) {
1082 err = -ENOBUFS;
1083 goto errout;
1084 }
1085
1086 err = fib_dump_info(skb, 0, 0, RTM_NEWROUTE, fri, 0);
1087 if (err < 0) {
1088 /* -EMSGSIZE implies BUG in fib_nlmsg_size() */
1089 WARN_ON(err == -EMSGSIZE);
1090 kfree_skb(skb);
1091 goto errout;
1092 }
1093
1094 rtnl_notify(skb, net, 0, RTNLGRP_IPV4_ROUTE, NULL, GFP_ATOMIC);
1095 goto out;
1096
1097errout:
1098 rtnl_set_sk_err(net, RTNLGRP_IPV4_ROUTE, err);
1099out:
1100 rcu_read_unlock();
1101}
1102EXPORT_SYMBOL_GPL(fib_alias_hw_flags_set);
1103
1104static void trie_rebalance(struct trie *t, struct key_vector *tn)
1105{
1106 while (!IS_TRIE(tn))
1107 tn = resize(t, tn);
1108}
1109
1110static int fib_insert_node(struct trie *t, struct key_vector *tp,
1111 struct fib_alias *new, t_key key)
1112{
1113 struct key_vector *n, *l;
1114
1115 l = leaf_new(key, new);
1116 if (!l)
1117 goto noleaf;
1118
1119 /* retrieve child from parent node */
1120 n = get_child(tp, get_index(key, tp));
1121
1122 /* Case 2: n is a LEAF or a TNODE and the key doesn't match.
1123 *
1124 * Add a new tnode here
1125 * first tnode need some special handling
1126 * leaves us in position for handling as case 3
1127 */
1128 if (n) {
1129 struct key_vector *tn;
1130
1131 tn = tnode_new(key, __fls(key ^ n->key), 1);
1132 if (!tn)
1133 goto notnode;
1134
1135 /* initialize routes out of node */
1136 NODE_INIT_PARENT(tn, tp);
1137 put_child(tn, get_index(key, tn) ^ 1, n);
1138
1139 /* start adding routes into the node */
1140 put_child_root(tp, key, tn);
1141 node_set_parent(n, tn);
1142
1143 /* parent now has a NULL spot where the leaf can go */
1144 tp = tn;
1145 }
1146
1147 /* Case 3: n is NULL, and will just insert a new leaf */
1148 node_push_suffix(tp, new->fa_slen);
1149 NODE_INIT_PARENT(l, tp);
1150 put_child_root(tp, key, l);
1151 trie_rebalance(t, tp);
1152
1153 return 0;
1154notnode:
1155 node_free(l);
1156noleaf:
1157 return -ENOMEM;
1158}
1159
1160static int fib_insert_alias(struct trie *t, struct key_vector *tp,
1161 struct key_vector *l, struct fib_alias *new,
1162 struct fib_alias *fa, t_key key)
1163{
1164 if (!l)
1165 return fib_insert_node(t, tp, new, key);
1166
1167 if (fa) {
1168 hlist_add_before_rcu(&new->fa_list, &fa->fa_list);
1169 } else {
1170 struct fib_alias *last;
1171
1172 hlist_for_each_entry(last, &l->leaf, fa_list) {
1173 if (new->fa_slen < last->fa_slen)
1174 break;
1175 if ((new->fa_slen == last->fa_slen) &&
1176 (new->tb_id > last->tb_id))
1177 break;
1178 fa = last;
1179 }
1180
1181 if (fa)
1182 hlist_add_behind_rcu(&new->fa_list, &fa->fa_list);
1183 else
1184 hlist_add_head_rcu(&new->fa_list, &l->leaf);
1185 }
1186
1187 /* if we added to the tail node then we need to update slen */
1188 if (l->slen < new->fa_slen) {
1189 l->slen = new->fa_slen;
1190 node_push_suffix(tp, new->fa_slen);
1191 }
1192
1193 return 0;
1194}
1195
1196static bool fib_valid_key_len(u32 key, u8 plen, struct netlink_ext_ack *extack)
1197{
1198 if (plen > KEYLENGTH) {
1199 NL_SET_ERR_MSG(extack, "Invalid prefix length");
1200 return false;
1201 }
1202
1203 if ((plen < KEYLENGTH) && (key << plen)) {
1204 NL_SET_ERR_MSG(extack,
1205 "Invalid prefix for given prefix length");
1206 return false;
1207 }
1208
1209 return true;
1210}
1211
1212static void fib_remove_alias(struct trie *t, struct key_vector *tp,
1213 struct key_vector *l, struct fib_alias *old);
1214
1215/* Caller must hold RTNL. */
1216int fib_table_insert(struct net *net, struct fib_table *tb,
1217 struct fib_config *cfg, struct netlink_ext_ack *extack)
1218{
1219 struct trie *t = (struct trie *)tb->tb_data;
1220 struct fib_alias *fa, *new_fa;
1221 struct key_vector *l, *tp;
1222 u16 nlflags = NLM_F_EXCL;
1223 struct fib_info *fi;
1224 u8 plen = cfg->fc_dst_len;
1225 u8 slen = KEYLENGTH - plen;
1226 dscp_t dscp;
1227 u32 key;
1228 int err;
1229
1230 key = ntohl(cfg->fc_dst);
1231
1232 if (!fib_valid_key_len(key, plen, extack))
1233 return -EINVAL;
1234
1235 pr_debug("Insert table=%u %08x/%d\n", tb->tb_id, key, plen);
1236
1237 fi = fib_create_info(cfg, extack);
1238 if (IS_ERR(fi)) {
1239 err = PTR_ERR(fi);
1240 goto err;
1241 }
1242
1243 dscp = cfg->fc_dscp;
1244 l = fib_find_node(t, &tp, key);
1245 fa = l ? fib_find_alias(&l->leaf, slen, dscp, fi->fib_priority,
1246 tb->tb_id, false) : NULL;
1247
1248 /* Now fa, if non-NULL, points to the first fib alias
1249 * with the same keys [prefix,dscp,priority], if such key already
1250 * exists or to the node before which we will insert new one.
1251 *
1252 * If fa is NULL, we will need to allocate a new one and
1253 * insert to the tail of the section matching the suffix length
1254 * of the new alias.
1255 */
1256
1257 if (fa && fa->fa_dscp == dscp &&
1258 fa->fa_info->fib_priority == fi->fib_priority) {
1259 struct fib_alias *fa_first, *fa_match;
1260
1261 err = -EEXIST;
1262 if (cfg->fc_nlflags & NLM_F_EXCL)
1263 goto out;
1264
1265 nlflags &= ~NLM_F_EXCL;
1266
1267 /* We have 2 goals:
1268 * 1. Find exact match for type, scope, fib_info to avoid
1269 * duplicate routes
1270 * 2. Find next 'fa' (or head), NLM_F_APPEND inserts before it
1271 */
1272 fa_match = NULL;
1273 fa_first = fa;
1274 hlist_for_each_entry_from(fa, fa_list) {
1275 if ((fa->fa_slen != slen) ||
1276 (fa->tb_id != tb->tb_id) ||
1277 (fa->fa_dscp != dscp))
1278 break;
1279 if (fa->fa_info->fib_priority != fi->fib_priority)
1280 break;
1281 if (fa->fa_type == cfg->fc_type &&
1282 fa->fa_info == fi) {
1283 fa_match = fa;
1284 break;
1285 }
1286 }
1287
1288 if (cfg->fc_nlflags & NLM_F_REPLACE) {
1289 struct fib_info *fi_drop;
1290 u8 state;
1291
1292 nlflags |= NLM_F_REPLACE;
1293 fa = fa_first;
1294 if (fa_match) {
1295 if (fa == fa_match)
1296 err = 0;
1297 goto out;
1298 }
1299 err = -ENOBUFS;
1300 new_fa = kmem_cache_alloc(fn_alias_kmem, GFP_KERNEL);
1301 if (!new_fa)
1302 goto out;
1303
1304 fi_drop = fa->fa_info;
1305 new_fa->fa_dscp = fa->fa_dscp;
1306 new_fa->fa_info = fi;
1307 new_fa->fa_type = cfg->fc_type;
1308 state = fa->fa_state;
1309 new_fa->fa_state = state & ~FA_S_ACCESSED;
1310 new_fa->fa_slen = fa->fa_slen;
1311 new_fa->tb_id = tb->tb_id;
1312 new_fa->fa_default = -1;
1313 new_fa->offload = 0;
1314 new_fa->trap = 0;
1315 new_fa->offload_failed = 0;
1316
1317 hlist_replace_rcu(&fa->fa_list, &new_fa->fa_list);
1318
1319 if (fib_find_alias(&l->leaf, fa->fa_slen, 0, 0,
1320 tb->tb_id, true) == new_fa) {
1321 enum fib_event_type fib_event;
1322
1323 fib_event = FIB_EVENT_ENTRY_REPLACE;
1324 err = call_fib_entry_notifiers(net, fib_event,
1325 key, plen,
1326 new_fa, extack);
1327 if (err) {
1328 hlist_replace_rcu(&new_fa->fa_list,
1329 &fa->fa_list);
1330 goto out_free_new_fa;
1331 }
1332 }
1333
1334 rtmsg_fib(RTM_NEWROUTE, htonl(key), new_fa, plen,
1335 tb->tb_id, &cfg->fc_nlinfo, nlflags);
1336
1337 alias_free_mem_rcu(fa);
1338
1339 fib_release_info(fi_drop);
1340 if (state & FA_S_ACCESSED)
1341 rt_cache_flush(cfg->fc_nlinfo.nl_net);
1342
1343 goto succeeded;
1344 }
1345 /* Error if we find a perfect match which
1346 * uses the same scope, type, and nexthop
1347 * information.
1348 */
1349 if (fa_match)
1350 goto out;
1351
1352 if (cfg->fc_nlflags & NLM_F_APPEND)
1353 nlflags |= NLM_F_APPEND;
1354 else
1355 fa = fa_first;
1356 }
1357 err = -ENOENT;
1358 if (!(cfg->fc_nlflags & NLM_F_CREATE))
1359 goto out;
1360
1361 nlflags |= NLM_F_CREATE;
1362 err = -ENOBUFS;
1363 new_fa = kmem_cache_alloc(fn_alias_kmem, GFP_KERNEL);
1364 if (!new_fa)
1365 goto out;
1366
1367 new_fa->fa_info = fi;
1368 new_fa->fa_dscp = dscp;
1369 new_fa->fa_type = cfg->fc_type;
1370 new_fa->fa_state = 0;
1371 new_fa->fa_slen = slen;
1372 new_fa->tb_id = tb->tb_id;
1373 new_fa->fa_default = -1;
1374 new_fa->offload = 0;
1375 new_fa->trap = 0;
1376 new_fa->offload_failed = 0;
1377
1378 /* Insert new entry to the list. */
1379 err = fib_insert_alias(t, tp, l, new_fa, fa, key);
1380 if (err)
1381 goto out_free_new_fa;
1382
1383 /* The alias was already inserted, so the node must exist. */
1384 l = l ? l : fib_find_node(t, &tp, key);
1385 if (WARN_ON_ONCE(!l)) {
1386 err = -ENOENT;
1387 goto out_free_new_fa;
1388 }
1389
1390 if (fib_find_alias(&l->leaf, new_fa->fa_slen, 0, 0, tb->tb_id, true) ==
1391 new_fa) {
1392 enum fib_event_type fib_event;
1393
1394 fib_event = FIB_EVENT_ENTRY_REPLACE;
1395 err = call_fib_entry_notifiers(net, fib_event, key, plen,
1396 new_fa, extack);
1397 if (err)
1398 goto out_remove_new_fa;
1399 }
1400
1401 if (!plen)
1402 tb->tb_num_default++;
1403
1404 rt_cache_flush(cfg->fc_nlinfo.nl_net);
1405 rtmsg_fib(RTM_NEWROUTE, htonl(key), new_fa, plen, new_fa->tb_id,
1406 &cfg->fc_nlinfo, nlflags);
1407succeeded:
1408 return 0;
1409
1410out_remove_new_fa:
1411 fib_remove_alias(t, tp, l, new_fa);
1412out_free_new_fa:
1413 kmem_cache_free(fn_alias_kmem, new_fa);
1414out:
1415 fib_release_info(fi);
1416err:
1417 return err;
1418}
1419
1420static inline t_key prefix_mismatch(t_key key, struct key_vector *n)
1421{
1422 t_key prefix = n->key;
1423
1424 return (key ^ prefix) & (prefix | -prefix);
1425}
1426
1427bool fib_lookup_good_nhc(const struct fib_nh_common *nhc, int fib_flags,
1428 const struct flowi4 *flp)
1429{
1430 if (nhc->nhc_flags & RTNH_F_DEAD)
1431 return false;
1432
1433 if (ip_ignore_linkdown(nhc->nhc_dev) &&
1434 nhc->nhc_flags & RTNH_F_LINKDOWN &&
1435 !(fib_flags & FIB_LOOKUP_IGNORE_LINKSTATE))
1436 return false;
1437
1438 if (flp->flowi4_oif && flp->flowi4_oif != nhc->nhc_oif)
1439 return false;
1440
1441 return true;
1442}
1443
1444/* should be called with rcu_read_lock */
1445int fib_table_lookup(struct fib_table *tb, const struct flowi4 *flp,
1446 struct fib_result *res, int fib_flags)
1447{
1448 struct trie *t = (struct trie *) tb->tb_data;
1449#ifdef CONFIG_IP_FIB_TRIE_STATS
1450 struct trie_use_stats __percpu *stats = t->stats;
1451#endif
1452 const t_key key = ntohl(flp->daddr);
1453 struct key_vector *n, *pn;
1454 struct fib_alias *fa;
1455 unsigned long index;
1456 t_key cindex;
1457
1458 pn = t->kv;
1459 cindex = 0;
1460
1461 n = get_child_rcu(pn, cindex);
1462 if (!n) {
1463 trace_fib_table_lookup(tb->tb_id, flp, NULL, -EAGAIN);
1464 return -EAGAIN;
1465 }
1466
1467#ifdef CONFIG_IP_FIB_TRIE_STATS
1468 this_cpu_inc(stats->gets);
1469#endif
1470
1471 /* Step 1: Travel to the longest prefix match in the trie */
1472 for (;;) {
1473 index = get_cindex(key, n);
1474
1475 /* This bit of code is a bit tricky but it combines multiple
1476 * checks into a single check. The prefix consists of the
1477 * prefix plus zeros for the "bits" in the prefix. The index
1478 * is the difference between the key and this value. From
1479 * this we can actually derive several pieces of data.
1480 * if (index >= (1ul << bits))
1481 * we have a mismatch in skip bits and failed
1482 * else
1483 * we know the value is cindex
1484 *
1485 * This check is safe even if bits == KEYLENGTH due to the
1486 * fact that we can only allocate a node with 32 bits if a
1487 * long is greater than 32 bits.
1488 */
1489 if (index >= (1ul << n->bits))
1490 break;
1491
1492 /* we have found a leaf. Prefixes have already been compared */
1493 if (IS_LEAF(n))
1494 goto found;
1495
1496 /* only record pn and cindex if we are going to be chopping
1497 * bits later. Otherwise we are just wasting cycles.
1498 */
1499 if (n->slen > n->pos) {
1500 pn = n;
1501 cindex = index;
1502 }
1503
1504 n = get_child_rcu(n, index);
1505 if (unlikely(!n))
1506 goto backtrace;
1507 }
1508
1509 /* Step 2: Sort out leaves and begin backtracing for longest prefix */
1510 for (;;) {
1511 /* record the pointer where our next node pointer is stored */
1512 struct key_vector __rcu **cptr = n->tnode;
1513
1514 /* This test verifies that none of the bits that differ
1515 * between the key and the prefix exist in the region of
1516 * the lsb and higher in the prefix.
1517 */
1518 if (unlikely(prefix_mismatch(key, n)) || (n->slen == n->pos))
1519 goto backtrace;
1520
1521 /* exit out and process leaf */
1522 if (unlikely(IS_LEAF(n)))
1523 break;
1524
1525 /* Don't bother recording parent info. Since we are in
1526 * prefix match mode we will have to come back to wherever
1527 * we started this traversal anyway
1528 */
1529
1530 while ((n = rcu_dereference(*cptr)) == NULL) {
1531backtrace:
1532#ifdef CONFIG_IP_FIB_TRIE_STATS
1533 if (!n)
1534 this_cpu_inc(stats->null_node_hit);
1535#endif
1536 /* If we are at cindex 0 there are no more bits for
1537 * us to strip at this level so we must ascend back
1538 * up one level to see if there are any more bits to
1539 * be stripped there.
1540 */
1541 while (!cindex) {
1542 t_key pkey = pn->key;
1543
1544 /* If we don't have a parent then there is
1545 * nothing for us to do as we do not have any
1546 * further nodes to parse.
1547 */
1548 if (IS_TRIE(pn)) {
1549 trace_fib_table_lookup(tb->tb_id, flp,
1550 NULL, -EAGAIN);
1551 return -EAGAIN;
1552 }
1553#ifdef CONFIG_IP_FIB_TRIE_STATS
1554 this_cpu_inc(stats->backtrack);
1555#endif
1556 /* Get Child's index */
1557 pn = node_parent_rcu(pn);
1558 cindex = get_index(pkey, pn);
1559 }
1560
1561 /* strip the least significant bit from the cindex */
1562 cindex &= cindex - 1;
1563
1564 /* grab pointer for next child node */
1565 cptr = &pn->tnode[cindex];
1566 }
1567 }
1568
1569found:
1570 /* this line carries forward the xor from earlier in the function */
1571 index = key ^ n->key;
1572
1573 /* Step 3: Process the leaf, if that fails fall back to backtracing */
1574 hlist_for_each_entry_rcu(fa, &n->leaf, fa_list) {
1575 struct fib_info *fi = fa->fa_info;
1576 struct fib_nh_common *nhc;
1577 int nhsel, err;
1578
1579 if ((BITS_PER_LONG > KEYLENGTH) || (fa->fa_slen < KEYLENGTH)) {
1580 if (index >= (1ul << fa->fa_slen))
1581 continue;
1582 }
1583 if (fa->fa_dscp &&
1584 inet_dscp_to_dsfield(fa->fa_dscp) != flp->flowi4_tos)
1585 continue;
1586 /* Paired with WRITE_ONCE() in fib_release_info() */
1587 if (READ_ONCE(fi->fib_dead))
1588 continue;
1589 if (fa->fa_info->fib_scope < flp->flowi4_scope)
1590 continue;
1591 fib_alias_accessed(fa);
1592 err = fib_props[fa->fa_type].error;
1593 if (unlikely(err < 0)) {
1594out_reject:
1595#ifdef CONFIG_IP_FIB_TRIE_STATS
1596 this_cpu_inc(stats->semantic_match_passed);
1597#endif
1598 trace_fib_table_lookup(tb->tb_id, flp, NULL, err);
1599 return err;
1600 }
1601 if (fi->fib_flags & RTNH_F_DEAD)
1602 continue;
1603
1604 if (unlikely(fi->nh)) {
1605 if (nexthop_is_blackhole(fi->nh)) {
1606 err = fib_props[RTN_BLACKHOLE].error;
1607 goto out_reject;
1608 }
1609
1610 nhc = nexthop_get_nhc_lookup(fi->nh, fib_flags, flp,
1611 &nhsel);
1612 if (nhc)
1613 goto set_result;
1614 goto miss;
1615 }
1616
1617 for (nhsel = 0; nhsel < fib_info_num_path(fi); nhsel++) {
1618 nhc = fib_info_nhc(fi, nhsel);
1619
1620 if (!fib_lookup_good_nhc(nhc, fib_flags, flp))
1621 continue;
1622set_result:
1623 if (!(fib_flags & FIB_LOOKUP_NOREF))
1624 refcount_inc(&fi->fib_clntref);
1625
1626 res->prefix = htonl(n->key);
1627 res->prefixlen = KEYLENGTH - fa->fa_slen;
1628 res->nh_sel = nhsel;
1629 res->nhc = nhc;
1630 res->type = fa->fa_type;
1631 res->scope = fi->fib_scope;
1632 res->fi = fi;
1633 res->table = tb;
1634 res->fa_head = &n->leaf;
1635#ifdef CONFIG_IP_FIB_TRIE_STATS
1636 this_cpu_inc(stats->semantic_match_passed);
1637#endif
1638 trace_fib_table_lookup(tb->tb_id, flp, nhc, err);
1639
1640 return err;
1641 }
1642 }
1643miss:
1644#ifdef CONFIG_IP_FIB_TRIE_STATS
1645 this_cpu_inc(stats->semantic_match_miss);
1646#endif
1647 goto backtrace;
1648}
1649EXPORT_SYMBOL_GPL(fib_table_lookup);
1650
1651static void fib_remove_alias(struct trie *t, struct key_vector *tp,
1652 struct key_vector *l, struct fib_alias *old)
1653{
1654 /* record the location of the previous list_info entry */
1655 struct hlist_node **pprev = old->fa_list.pprev;
1656 struct fib_alias *fa = hlist_entry(pprev, typeof(*fa), fa_list.next);
1657
1658 /* remove the fib_alias from the list */
1659 hlist_del_rcu(&old->fa_list);
1660
1661 /* if we emptied the list this leaf will be freed and we can sort
1662 * out parent suffix lengths as a part of trie_rebalance
1663 */
1664 if (hlist_empty(&l->leaf)) {
1665 if (tp->slen == l->slen)
1666 node_pull_suffix(tp, tp->pos);
1667 put_child_root(tp, l->key, NULL);
1668 node_free(l);
1669 trie_rebalance(t, tp);
1670 return;
1671 }
1672
1673 /* only access fa if it is pointing at the last valid hlist_node */
1674 if (*pprev)
1675 return;
1676
1677 /* update the trie with the latest suffix length */
1678 l->slen = fa->fa_slen;
1679 node_pull_suffix(tp, fa->fa_slen);
1680}
1681
1682static void fib_notify_alias_delete(struct net *net, u32 key,
1683 struct hlist_head *fah,
1684 struct fib_alias *fa_to_delete,
1685 struct netlink_ext_ack *extack)
1686{
1687 struct fib_alias *fa_next, *fa_to_notify;
1688 u32 tb_id = fa_to_delete->tb_id;
1689 u8 slen = fa_to_delete->fa_slen;
1690 enum fib_event_type fib_event;
1691
1692 /* Do not notify if we do not care about the route. */
1693 if (fib_find_alias(fah, slen, 0, 0, tb_id, true) != fa_to_delete)
1694 return;
1695
1696 /* Determine if the route should be replaced by the next route in the
1697 * list.
1698 */
1699 fa_next = hlist_entry_safe(fa_to_delete->fa_list.next,
1700 struct fib_alias, fa_list);
1701 if (fa_next && fa_next->fa_slen == slen && fa_next->tb_id == tb_id) {
1702 fib_event = FIB_EVENT_ENTRY_REPLACE;
1703 fa_to_notify = fa_next;
1704 } else {
1705 fib_event = FIB_EVENT_ENTRY_DEL;
1706 fa_to_notify = fa_to_delete;
1707 }
1708 call_fib_entry_notifiers(net, fib_event, key, KEYLENGTH - slen,
1709 fa_to_notify, extack);
1710}
1711
1712/* Caller must hold RTNL. */
1713int fib_table_delete(struct net *net, struct fib_table *tb,
1714 struct fib_config *cfg, struct netlink_ext_ack *extack)
1715{
1716 struct trie *t = (struct trie *) tb->tb_data;
1717 struct fib_alias *fa, *fa_to_delete;
1718 struct key_vector *l, *tp;
1719 u8 plen = cfg->fc_dst_len;
1720 u8 slen = KEYLENGTH - plen;
1721 dscp_t dscp;
1722 u32 key;
1723
1724 key = ntohl(cfg->fc_dst);
1725
1726 if (!fib_valid_key_len(key, plen, extack))
1727 return -EINVAL;
1728
1729 l = fib_find_node(t, &tp, key);
1730 if (!l)
1731 return -ESRCH;
1732
1733 dscp = cfg->fc_dscp;
1734 fa = fib_find_alias(&l->leaf, slen, dscp, 0, tb->tb_id, false);
1735 if (!fa)
1736 return -ESRCH;
1737
1738 pr_debug("Deleting %08x/%d dsfield=0x%02x t=%p\n", key, plen,
1739 inet_dscp_to_dsfield(dscp), t);
1740
1741 fa_to_delete = NULL;
1742 hlist_for_each_entry_from(fa, fa_list) {
1743 struct fib_info *fi = fa->fa_info;
1744
1745 if ((fa->fa_slen != slen) ||
1746 (fa->tb_id != tb->tb_id) ||
1747 (fa->fa_dscp != dscp))
1748 break;
1749
1750 if ((!cfg->fc_type || fa->fa_type == cfg->fc_type) &&
1751 (cfg->fc_scope == RT_SCOPE_NOWHERE ||
1752 fa->fa_info->fib_scope == cfg->fc_scope) &&
1753 (!cfg->fc_prefsrc ||
1754 fi->fib_prefsrc == cfg->fc_prefsrc) &&
1755 (!cfg->fc_protocol ||
1756 fi->fib_protocol == cfg->fc_protocol) &&
1757 fib_nh_match(net, cfg, fi, extack) == 0 &&
1758 fib_metrics_match(cfg, fi)) {
1759 fa_to_delete = fa;
1760 break;
1761 }
1762 }
1763
1764 if (!fa_to_delete)
1765 return -ESRCH;
1766
1767 fib_notify_alias_delete(net, key, &l->leaf, fa_to_delete, extack);
1768 rtmsg_fib(RTM_DELROUTE, htonl(key), fa_to_delete, plen, tb->tb_id,
1769 &cfg->fc_nlinfo, 0);
1770
1771 if (!plen)
1772 tb->tb_num_default--;
1773
1774 fib_remove_alias(t, tp, l, fa_to_delete);
1775
1776 if (fa_to_delete->fa_state & FA_S_ACCESSED)
1777 rt_cache_flush(cfg->fc_nlinfo.nl_net);
1778
1779 fib_release_info(fa_to_delete->fa_info);
1780 alias_free_mem_rcu(fa_to_delete);
1781 return 0;
1782}
1783
1784/* Scan for the next leaf starting at the provided key value */
1785static struct key_vector *leaf_walk_rcu(struct key_vector **tn, t_key key)
1786{
1787 struct key_vector *pn, *n = *tn;
1788 unsigned long cindex;
1789
1790 /* this loop is meant to try and find the key in the trie */
1791 do {
1792 /* record parent and next child index */
1793 pn = n;
1794 cindex = (key > pn->key) ? get_index(key, pn) : 0;
1795
1796 if (cindex >> pn->bits)
1797 break;
1798
1799 /* descend into the next child */
1800 n = get_child_rcu(pn, cindex++);
1801 if (!n)
1802 break;
1803
1804 /* guarantee forward progress on the keys */
1805 if (IS_LEAF(n) && (n->key >= key))
1806 goto found;
1807 } while (IS_TNODE(n));
1808
1809 /* this loop will search for the next leaf with a greater key */
1810 while (!IS_TRIE(pn)) {
1811 /* if we exhausted the parent node we will need to climb */
1812 if (cindex >= (1ul << pn->bits)) {
1813 t_key pkey = pn->key;
1814
1815 pn = node_parent_rcu(pn);
1816 cindex = get_index(pkey, pn) + 1;
1817 continue;
1818 }
1819
1820 /* grab the next available node */
1821 n = get_child_rcu(pn, cindex++);
1822 if (!n)
1823 continue;
1824
1825 /* no need to compare keys since we bumped the index */
1826 if (IS_LEAF(n))
1827 goto found;
1828
1829 /* Rescan start scanning in new node */
1830 pn = n;
1831 cindex = 0;
1832 }
1833
1834 *tn = pn;
1835 return NULL; /* Root of trie */
1836found:
1837 /* if we are at the limit for keys just return NULL for the tnode */
1838 *tn = pn;
1839 return n;
1840}
1841
1842static void fib_trie_free(struct fib_table *tb)
1843{
1844 struct trie *t = (struct trie *)tb->tb_data;
1845 struct key_vector *pn = t->kv;
1846 unsigned long cindex = 1;
1847 struct hlist_node *tmp;
1848 struct fib_alias *fa;
1849
1850 /* walk trie in reverse order and free everything */
1851 for (;;) {
1852 struct key_vector *n;
1853
1854 if (!(cindex--)) {
1855 t_key pkey = pn->key;
1856
1857 if (IS_TRIE(pn))
1858 break;
1859
1860 n = pn;
1861 pn = node_parent(pn);
1862
1863 /* drop emptied tnode */
1864 put_child_root(pn, n->key, NULL);
1865 node_free(n);
1866
1867 cindex = get_index(pkey, pn);
1868
1869 continue;
1870 }
1871
1872 /* grab the next available node */
1873 n = get_child(pn, cindex);
1874 if (!n)
1875 continue;
1876
1877 if (IS_TNODE(n)) {
1878 /* record pn and cindex for leaf walking */
1879 pn = n;
1880 cindex = 1ul << n->bits;
1881
1882 continue;
1883 }
1884
1885 hlist_for_each_entry_safe(fa, tmp, &n->leaf, fa_list) {
1886 hlist_del_rcu(&fa->fa_list);
1887 alias_free_mem_rcu(fa);
1888 }
1889
1890 put_child_root(pn, n->key, NULL);
1891 node_free(n);
1892 }
1893
1894#ifdef CONFIG_IP_FIB_TRIE_STATS
1895 free_percpu(t->stats);
1896#endif
1897 kfree(tb);
1898}
1899
1900struct fib_table *fib_trie_unmerge(struct fib_table *oldtb)
1901{
1902 struct trie *ot = (struct trie *)oldtb->tb_data;
1903 struct key_vector *l, *tp = ot->kv;
1904 struct fib_table *local_tb;
1905 struct fib_alias *fa;
1906 struct trie *lt;
1907 t_key key = 0;
1908
1909 if (oldtb->tb_data == oldtb->__data)
1910 return oldtb;
1911
1912 local_tb = fib_trie_table(RT_TABLE_LOCAL, NULL);
1913 if (!local_tb)
1914 return NULL;
1915
1916 lt = (struct trie *)local_tb->tb_data;
1917
1918 while ((l = leaf_walk_rcu(&tp, key)) != NULL) {
1919 struct key_vector *local_l = NULL, *local_tp;
1920
1921 hlist_for_each_entry(fa, &l->leaf, fa_list) {
1922 struct fib_alias *new_fa;
1923
1924 if (local_tb->tb_id != fa->tb_id)
1925 continue;
1926
1927 /* clone fa for new local table */
1928 new_fa = kmem_cache_alloc(fn_alias_kmem, GFP_KERNEL);
1929 if (!new_fa)
1930 goto out;
1931
1932 memcpy(new_fa, fa, sizeof(*fa));
1933
1934 /* insert clone into table */
1935 if (!local_l)
1936 local_l = fib_find_node(lt, &local_tp, l->key);
1937
1938 if (fib_insert_alias(lt, local_tp, local_l, new_fa,
1939 NULL, l->key)) {
1940 kmem_cache_free(fn_alias_kmem, new_fa);
1941 goto out;
1942 }
1943 }
1944
1945 /* stop loop if key wrapped back to 0 */
1946 key = l->key + 1;
1947 if (key < l->key)
1948 break;
1949 }
1950
1951 return local_tb;
1952out:
1953 fib_trie_free(local_tb);
1954
1955 return NULL;
1956}
1957
1958/* Caller must hold RTNL */
1959void fib_table_flush_external(struct fib_table *tb)
1960{
1961 struct trie *t = (struct trie *)tb->tb_data;
1962 struct key_vector *pn = t->kv;
1963 unsigned long cindex = 1;
1964 struct hlist_node *tmp;
1965 struct fib_alias *fa;
1966
1967 /* walk trie in reverse order */
1968 for (;;) {
1969 unsigned char slen = 0;
1970 struct key_vector *n;
1971
1972 if (!(cindex--)) {
1973 t_key pkey = pn->key;
1974
1975 /* cannot resize the trie vector */
1976 if (IS_TRIE(pn))
1977 break;
1978
1979 /* update the suffix to address pulled leaves */
1980 if (pn->slen > pn->pos)
1981 update_suffix(pn);
1982
1983 /* resize completed node */
1984 pn = resize(t, pn);
1985 cindex = get_index(pkey, pn);
1986
1987 continue;
1988 }
1989
1990 /* grab the next available node */
1991 n = get_child(pn, cindex);
1992 if (!n)
1993 continue;
1994
1995 if (IS_TNODE(n)) {
1996 /* record pn and cindex for leaf walking */
1997 pn = n;
1998 cindex = 1ul << n->bits;
1999
2000 continue;
2001 }
2002
2003 hlist_for_each_entry_safe(fa, tmp, &n->leaf, fa_list) {
2004 /* if alias was cloned to local then we just
2005 * need to remove the local copy from main
2006 */
2007 if (tb->tb_id != fa->tb_id) {
2008 hlist_del_rcu(&fa->fa_list);
2009 alias_free_mem_rcu(fa);
2010 continue;
2011 }
2012
2013 /* record local slen */
2014 slen = fa->fa_slen;
2015 }
2016
2017 /* update leaf slen */
2018 n->slen = slen;
2019
2020 if (hlist_empty(&n->leaf)) {
2021 put_child_root(pn, n->key, NULL);
2022 node_free(n);
2023 }
2024 }
2025}
2026
2027/* Caller must hold RTNL. */
2028int fib_table_flush(struct net *net, struct fib_table *tb, bool flush_all)
2029{
2030 struct trie *t = (struct trie *)tb->tb_data;
2031 struct nl_info info = { .nl_net = net };
2032 struct key_vector *pn = t->kv;
2033 unsigned long cindex = 1;
2034 struct hlist_node *tmp;
2035 struct fib_alias *fa;
2036 int found = 0;
2037
2038 /* walk trie in reverse order */
2039 for (;;) {
2040 unsigned char slen = 0;
2041 struct key_vector *n;
2042
2043 if (!(cindex--)) {
2044 t_key pkey = pn->key;
2045
2046 /* cannot resize the trie vector */
2047 if (IS_TRIE(pn))
2048 break;
2049
2050 /* update the suffix to address pulled leaves */
2051 if (pn->slen > pn->pos)
2052 update_suffix(pn);
2053
2054 /* resize completed node */
2055 pn = resize(t, pn);
2056 cindex = get_index(pkey, pn);
2057
2058 continue;
2059 }
2060
2061 /* grab the next available node */
2062 n = get_child(pn, cindex);
2063 if (!n)
2064 continue;
2065
2066 if (IS_TNODE(n)) {
2067 /* record pn and cindex for leaf walking */
2068 pn = n;
2069 cindex = 1ul << n->bits;
2070
2071 continue;
2072 }
2073
2074 hlist_for_each_entry_safe(fa, tmp, &n->leaf, fa_list) {
2075 struct fib_info *fi = fa->fa_info;
2076
2077 if (!fi || tb->tb_id != fa->tb_id ||
2078 (!(fi->fib_flags & RTNH_F_DEAD) &&
2079 !fib_props[fa->fa_type].error)) {
2080 slen = fa->fa_slen;
2081 continue;
2082 }
2083
2084 /* Do not flush error routes if network namespace is
2085 * not being dismantled
2086 */
2087 if (!flush_all && fib_props[fa->fa_type].error) {
2088 slen = fa->fa_slen;
2089 continue;
2090 }
2091
2092 fib_notify_alias_delete(net, n->key, &n->leaf, fa,
2093 NULL);
2094 if (fi->pfsrc_removed)
2095 rtmsg_fib(RTM_DELROUTE, htonl(n->key), fa,
2096 KEYLENGTH - fa->fa_slen, tb->tb_id, &info, 0);
2097 hlist_del_rcu(&fa->fa_list);
2098 fib_release_info(fa->fa_info);
2099 alias_free_mem_rcu(fa);
2100 found++;
2101 }
2102
2103 /* update leaf slen */
2104 n->slen = slen;
2105
2106 if (hlist_empty(&n->leaf)) {
2107 put_child_root(pn, n->key, NULL);
2108 node_free(n);
2109 }
2110 }
2111
2112 pr_debug("trie_flush found=%d\n", found);
2113 return found;
2114}
2115
2116/* derived from fib_trie_free */
2117static void __fib_info_notify_update(struct net *net, struct fib_table *tb,
2118 struct nl_info *info)
2119{
2120 struct trie *t = (struct trie *)tb->tb_data;
2121 struct key_vector *pn = t->kv;
2122 unsigned long cindex = 1;
2123 struct fib_alias *fa;
2124
2125 for (;;) {
2126 struct key_vector *n;
2127
2128 if (!(cindex--)) {
2129 t_key pkey = pn->key;
2130
2131 if (IS_TRIE(pn))
2132 break;
2133
2134 pn = node_parent(pn);
2135 cindex = get_index(pkey, pn);
2136 continue;
2137 }
2138
2139 /* grab the next available node */
2140 n = get_child(pn, cindex);
2141 if (!n)
2142 continue;
2143
2144 if (IS_TNODE(n)) {
2145 /* record pn and cindex for leaf walking */
2146 pn = n;
2147 cindex = 1ul << n->bits;
2148
2149 continue;
2150 }
2151
2152 hlist_for_each_entry(fa, &n->leaf, fa_list) {
2153 struct fib_info *fi = fa->fa_info;
2154
2155 if (!fi || !fi->nh_updated || fa->tb_id != tb->tb_id)
2156 continue;
2157
2158 rtmsg_fib(RTM_NEWROUTE, htonl(n->key), fa,
2159 KEYLENGTH - fa->fa_slen, tb->tb_id,
2160 info, NLM_F_REPLACE);
2161 }
2162 }
2163}
2164
2165void fib_info_notify_update(struct net *net, struct nl_info *info)
2166{
2167 unsigned int h;
2168
2169 for (h = 0; h < FIB_TABLE_HASHSZ; h++) {
2170 struct hlist_head *head = &net->ipv4.fib_table_hash[h];
2171 struct fib_table *tb;
2172
2173 hlist_for_each_entry_rcu(tb, head, tb_hlist,
2174 lockdep_rtnl_is_held())
2175 __fib_info_notify_update(net, tb, info);
2176 }
2177}
2178
2179static int fib_leaf_notify(struct key_vector *l, struct fib_table *tb,
2180 struct notifier_block *nb,
2181 struct netlink_ext_ack *extack)
2182{
2183 struct fib_alias *fa;
2184 int last_slen = -1;
2185 int err;
2186
2187 hlist_for_each_entry_rcu(fa, &l->leaf, fa_list) {
2188 struct fib_info *fi = fa->fa_info;
2189
2190 if (!fi)
2191 continue;
2192
2193 /* local and main table can share the same trie,
2194 * so don't notify twice for the same entry.
2195 */
2196 if (tb->tb_id != fa->tb_id)
2197 continue;
2198
2199 if (fa->fa_slen == last_slen)
2200 continue;
2201
2202 last_slen = fa->fa_slen;
2203 err = call_fib_entry_notifier(nb, FIB_EVENT_ENTRY_REPLACE,
2204 l->key, KEYLENGTH - fa->fa_slen,
2205 fa, extack);
2206 if (err)
2207 return err;
2208 }
2209 return 0;
2210}
2211
2212static int fib_table_notify(struct fib_table *tb, struct notifier_block *nb,
2213 struct netlink_ext_ack *extack)
2214{
2215 struct trie *t = (struct trie *)tb->tb_data;
2216 struct key_vector *l, *tp = t->kv;
2217 t_key key = 0;
2218 int err;
2219
2220 while ((l = leaf_walk_rcu(&tp, key)) != NULL) {
2221 err = fib_leaf_notify(l, tb, nb, extack);
2222 if (err)
2223 return err;
2224
2225 key = l->key + 1;
2226 /* stop in case of wrap around */
2227 if (key < l->key)
2228 break;
2229 }
2230 return 0;
2231}
2232
2233int fib_notify(struct net *net, struct notifier_block *nb,
2234 struct netlink_ext_ack *extack)
2235{
2236 unsigned int h;
2237 int err;
2238
2239 for (h = 0; h < FIB_TABLE_HASHSZ; h++) {
2240 struct hlist_head *head = &net->ipv4.fib_table_hash[h];
2241 struct fib_table *tb;
2242
2243 hlist_for_each_entry_rcu(tb, head, tb_hlist) {
2244 err = fib_table_notify(tb, nb, extack);
2245 if (err)
2246 return err;
2247 }
2248 }
2249 return 0;
2250}
2251
2252static void __trie_free_rcu(struct rcu_head *head)
2253{
2254 struct fib_table *tb = container_of(head, struct fib_table, rcu);
2255#ifdef CONFIG_IP_FIB_TRIE_STATS
2256 struct trie *t = (struct trie *)tb->tb_data;
2257
2258 if (tb->tb_data == tb->__data)
2259 free_percpu(t->stats);
2260#endif /* CONFIG_IP_FIB_TRIE_STATS */
2261 kfree(tb);
2262}
2263
2264void fib_free_table(struct fib_table *tb)
2265{
2266 call_rcu(&tb->rcu, __trie_free_rcu);
2267}
2268
2269static int fn_trie_dump_leaf(struct key_vector *l, struct fib_table *tb,
2270 struct sk_buff *skb, struct netlink_callback *cb,
2271 struct fib_dump_filter *filter)
2272{
2273 unsigned int flags = NLM_F_MULTI;
2274 __be32 xkey = htonl(l->key);
2275 int i, s_i, i_fa, s_fa, err;
2276 struct fib_alias *fa;
2277
2278 if (filter->filter_set ||
2279 !filter->dump_exceptions || !filter->dump_routes)
2280 flags |= NLM_F_DUMP_FILTERED;
2281
2282 s_i = cb->args[4];
2283 s_fa = cb->args[5];
2284 i = 0;
2285
2286 /* rcu_read_lock is hold by caller */
2287 hlist_for_each_entry_rcu(fa, &l->leaf, fa_list) {
2288 struct fib_info *fi = fa->fa_info;
2289
2290 if (i < s_i)
2291 goto next;
2292
2293 i_fa = 0;
2294
2295 if (tb->tb_id != fa->tb_id)
2296 goto next;
2297
2298 if (filter->filter_set) {
2299 if (filter->rt_type && fa->fa_type != filter->rt_type)
2300 goto next;
2301
2302 if ((filter->protocol &&
2303 fi->fib_protocol != filter->protocol))
2304 goto next;
2305
2306 if (filter->dev &&
2307 !fib_info_nh_uses_dev(fi, filter->dev))
2308 goto next;
2309 }
2310
2311 if (filter->dump_routes) {
2312 if (!s_fa) {
2313 struct fib_rt_info fri;
2314
2315 fri.fi = fi;
2316 fri.tb_id = tb->tb_id;
2317 fri.dst = xkey;
2318 fri.dst_len = KEYLENGTH - fa->fa_slen;
2319 fri.dscp = fa->fa_dscp;
2320 fri.type = fa->fa_type;
2321 fri.offload = READ_ONCE(fa->offload);
2322 fri.trap = READ_ONCE(fa->trap);
2323 fri.offload_failed = READ_ONCE(fa->offload_failed);
2324 err = fib_dump_info(skb,
2325 NETLINK_CB(cb->skb).portid,
2326 cb->nlh->nlmsg_seq,
2327 RTM_NEWROUTE, &fri, flags);
2328 if (err < 0)
2329 goto stop;
2330 }
2331
2332 i_fa++;
2333 }
2334
2335 if (filter->dump_exceptions) {
2336 err = fib_dump_info_fnhe(skb, cb, tb->tb_id, fi,
2337 &i_fa, s_fa, flags);
2338 if (err < 0)
2339 goto stop;
2340 }
2341
2342next:
2343 i++;
2344 }
2345
2346 cb->args[4] = i;
2347 return skb->len;
2348
2349stop:
2350 cb->args[4] = i;
2351 cb->args[5] = i_fa;
2352 return err;
2353}
2354
2355/* rcu_read_lock needs to be hold by caller from readside */
2356int fib_table_dump(struct fib_table *tb, struct sk_buff *skb,
2357 struct netlink_callback *cb, struct fib_dump_filter *filter)
2358{
2359 struct trie *t = (struct trie *)tb->tb_data;
2360 struct key_vector *l, *tp = t->kv;
2361 /* Dump starting at last key.
2362 * Note: 0.0.0.0/0 (ie default) is first key.
2363 */
2364 int count = cb->args[2];
2365 t_key key = cb->args[3];
2366
2367 /* First time here, count and key are both always 0. Count > 0
2368 * and key == 0 means the dump has wrapped around and we are done.
2369 */
2370 if (count && !key)
2371 return 0;
2372
2373 while ((l = leaf_walk_rcu(&tp, key)) != NULL) {
2374 int err;
2375
2376 err = fn_trie_dump_leaf(l, tb, skb, cb, filter);
2377 if (err < 0) {
2378 cb->args[3] = key;
2379 cb->args[2] = count;
2380 return err;
2381 }
2382
2383 ++count;
2384 key = l->key + 1;
2385
2386 memset(&cb->args[4], 0,
2387 sizeof(cb->args) - 4*sizeof(cb->args[0]));
2388
2389 /* stop loop if key wrapped back to 0 */
2390 if (key < l->key)
2391 break;
2392 }
2393
2394 cb->args[3] = key;
2395 cb->args[2] = count;
2396
2397 return 0;
2398}
2399
2400void __init fib_trie_init(void)
2401{
2402 fn_alias_kmem = kmem_cache_create("ip_fib_alias",
2403 sizeof(struct fib_alias),
2404 0, SLAB_PANIC | SLAB_ACCOUNT, NULL);
2405
2406 trie_leaf_kmem = kmem_cache_create("ip_fib_trie",
2407 LEAF_SIZE,
2408 0, SLAB_PANIC | SLAB_ACCOUNT, NULL);
2409}
2410
2411struct fib_table *fib_trie_table(u32 id, struct fib_table *alias)
2412{
2413 struct fib_table *tb;
2414 struct trie *t;
2415 size_t sz = sizeof(*tb);
2416
2417 if (!alias)
2418 sz += sizeof(struct trie);
2419
2420 tb = kzalloc(sz, GFP_KERNEL);
2421 if (!tb)
2422 return NULL;
2423
2424 tb->tb_id = id;
2425 tb->tb_num_default = 0;
2426 tb->tb_data = (alias ? alias->__data : tb->__data);
2427
2428 if (alias)
2429 return tb;
2430
2431 t = (struct trie *) tb->tb_data;
2432 t->kv[0].pos = KEYLENGTH;
2433 t->kv[0].slen = KEYLENGTH;
2434#ifdef CONFIG_IP_FIB_TRIE_STATS
2435 t->stats = alloc_percpu(struct trie_use_stats);
2436 if (!t->stats) {
2437 kfree(tb);
2438 tb = NULL;
2439 }
2440#endif
2441
2442 return tb;
2443}
2444
2445#ifdef CONFIG_PROC_FS
2446/* Depth first Trie walk iterator */
2447struct fib_trie_iter {
2448 struct seq_net_private p;
2449 struct fib_table *tb;
2450 struct key_vector *tnode;
2451 unsigned int index;
2452 unsigned int depth;
2453};
2454
2455static struct key_vector *fib_trie_get_next(struct fib_trie_iter *iter)
2456{
2457 unsigned long cindex = iter->index;
2458 struct key_vector *pn = iter->tnode;
2459 t_key pkey;
2460
2461 pr_debug("get_next iter={node=%p index=%d depth=%d}\n",
2462 iter->tnode, iter->index, iter->depth);
2463
2464 while (!IS_TRIE(pn)) {
2465 while (cindex < child_length(pn)) {
2466 struct key_vector *n = get_child_rcu(pn, cindex++);
2467
2468 if (!n)
2469 continue;
2470
2471 if (IS_LEAF(n)) {
2472 iter->tnode = pn;
2473 iter->index = cindex;
2474 } else {
2475 /* push down one level */
2476 iter->tnode = n;
2477 iter->index = 0;
2478 ++iter->depth;
2479 }
2480
2481 return n;
2482 }
2483
2484 /* Current node exhausted, pop back up */
2485 pkey = pn->key;
2486 pn = node_parent_rcu(pn);
2487 cindex = get_index(pkey, pn) + 1;
2488 --iter->depth;
2489 }
2490
2491 /* record root node so further searches know we are done */
2492 iter->tnode = pn;
2493 iter->index = 0;
2494
2495 return NULL;
2496}
2497
2498static struct key_vector *fib_trie_get_first(struct fib_trie_iter *iter,
2499 struct trie *t)
2500{
2501 struct key_vector *n, *pn;
2502
2503 if (!t)
2504 return NULL;
2505
2506 pn = t->kv;
2507 n = rcu_dereference(pn->tnode[0]);
2508 if (!n)
2509 return NULL;
2510
2511 if (IS_TNODE(n)) {
2512 iter->tnode = n;
2513 iter->index = 0;
2514 iter->depth = 1;
2515 } else {
2516 iter->tnode = pn;
2517 iter->index = 0;
2518 iter->depth = 0;
2519 }
2520
2521 return n;
2522}
2523
2524static void trie_collect_stats(struct trie *t, struct trie_stat *s)
2525{
2526 struct key_vector *n;
2527 struct fib_trie_iter iter;
2528
2529 memset(s, 0, sizeof(*s));
2530
2531 rcu_read_lock();
2532 for (n = fib_trie_get_first(&iter, t); n; n = fib_trie_get_next(&iter)) {
2533 if (IS_LEAF(n)) {
2534 struct fib_alias *fa;
2535
2536 s->leaves++;
2537 s->totdepth += iter.depth;
2538 if (iter.depth > s->maxdepth)
2539 s->maxdepth = iter.depth;
2540
2541 hlist_for_each_entry_rcu(fa, &n->leaf, fa_list)
2542 ++s->prefixes;
2543 } else {
2544 s->tnodes++;
2545 if (n->bits < MAX_STAT_DEPTH)
2546 s->nodesizes[n->bits]++;
2547 s->nullpointers += tn_info(n)->empty_children;
2548 }
2549 }
2550 rcu_read_unlock();
2551}
2552
2553/*
2554 * This outputs /proc/net/fib_triestats
2555 */
2556static void trie_show_stats(struct seq_file *seq, struct trie_stat *stat)
2557{
2558 unsigned int i, max, pointers, bytes, avdepth;
2559
2560 if (stat->leaves)
2561 avdepth = stat->totdepth*100 / stat->leaves;
2562 else
2563 avdepth = 0;
2564
2565 seq_printf(seq, "\tAver depth: %u.%02d\n",
2566 avdepth / 100, avdepth % 100);
2567 seq_printf(seq, "\tMax depth: %u\n", stat->maxdepth);
2568
2569 seq_printf(seq, "\tLeaves: %u\n", stat->leaves);
2570 bytes = LEAF_SIZE * stat->leaves;
2571
2572 seq_printf(seq, "\tPrefixes: %u\n", stat->prefixes);
2573 bytes += sizeof(struct fib_alias) * stat->prefixes;
2574
2575 seq_printf(seq, "\tInternal nodes: %u\n\t", stat->tnodes);
2576 bytes += TNODE_SIZE(0) * stat->tnodes;
2577
2578 max = MAX_STAT_DEPTH;
2579 while (max > 0 && stat->nodesizes[max-1] == 0)
2580 max--;
2581
2582 pointers = 0;
2583 for (i = 1; i < max; i++)
2584 if (stat->nodesizes[i] != 0) {
2585 seq_printf(seq, " %u: %u", i, stat->nodesizes[i]);
2586 pointers += (1<<i) * stat->nodesizes[i];
2587 }
2588 seq_putc(seq, '\n');
2589 seq_printf(seq, "\tPointers: %u\n", pointers);
2590
2591 bytes += sizeof(struct key_vector *) * pointers;
2592 seq_printf(seq, "Null ptrs: %u\n", stat->nullpointers);
2593 seq_printf(seq, "Total size: %u kB\n", (bytes + 1023) / 1024);
2594}
2595
2596#ifdef CONFIG_IP_FIB_TRIE_STATS
2597static void trie_show_usage(struct seq_file *seq,
2598 const struct trie_use_stats __percpu *stats)
2599{
2600 struct trie_use_stats s = { 0 };
2601 int cpu;
2602
2603 /* loop through all of the CPUs and gather up the stats */
2604 for_each_possible_cpu(cpu) {
2605 const struct trie_use_stats *pcpu = per_cpu_ptr(stats, cpu);
2606
2607 s.gets += pcpu->gets;
2608 s.backtrack += pcpu->backtrack;
2609 s.semantic_match_passed += pcpu->semantic_match_passed;
2610 s.semantic_match_miss += pcpu->semantic_match_miss;
2611 s.null_node_hit += pcpu->null_node_hit;
2612 s.resize_node_skipped += pcpu->resize_node_skipped;
2613 }
2614
2615 seq_printf(seq, "\nCounters:\n---------\n");
2616 seq_printf(seq, "gets = %u\n", s.gets);
2617 seq_printf(seq, "backtracks = %u\n", s.backtrack);
2618 seq_printf(seq, "semantic match passed = %u\n",
2619 s.semantic_match_passed);
2620 seq_printf(seq, "semantic match miss = %u\n", s.semantic_match_miss);
2621 seq_printf(seq, "null node hit= %u\n", s.null_node_hit);
2622 seq_printf(seq, "skipped node resize = %u\n\n", s.resize_node_skipped);
2623}
2624#endif /* CONFIG_IP_FIB_TRIE_STATS */
2625
2626static void fib_table_print(struct seq_file *seq, struct fib_table *tb)
2627{
2628 if (tb->tb_id == RT_TABLE_LOCAL)
2629 seq_puts(seq, "Local:\n");
2630 else if (tb->tb_id == RT_TABLE_MAIN)
2631 seq_puts(seq, "Main:\n");
2632 else
2633 seq_printf(seq, "Id %d:\n", tb->tb_id);
2634}
2635
2636
2637static int fib_triestat_seq_show(struct seq_file *seq, void *v)
2638{
2639 struct net *net = seq->private;
2640 unsigned int h;
2641
2642 seq_printf(seq,
2643 "Basic info: size of leaf:"
2644 " %zd bytes, size of tnode: %zd bytes.\n",
2645 LEAF_SIZE, TNODE_SIZE(0));
2646
2647 rcu_read_lock();
2648 for (h = 0; h < FIB_TABLE_HASHSZ; h++) {
2649 struct hlist_head *head = &net->ipv4.fib_table_hash[h];
2650 struct fib_table *tb;
2651
2652 hlist_for_each_entry_rcu(tb, head, tb_hlist) {
2653 struct trie *t = (struct trie *) tb->tb_data;
2654 struct trie_stat stat;
2655
2656 if (!t)
2657 continue;
2658
2659 fib_table_print(seq, tb);
2660
2661 trie_collect_stats(t, &stat);
2662 trie_show_stats(seq, &stat);
2663#ifdef CONFIG_IP_FIB_TRIE_STATS
2664 trie_show_usage(seq, t->stats);
2665#endif
2666 }
2667 cond_resched_rcu();
2668 }
2669 rcu_read_unlock();
2670
2671 return 0;
2672}
2673
2674static struct key_vector *fib_trie_get_idx(struct seq_file *seq, loff_t pos)
2675{
2676 struct fib_trie_iter *iter = seq->private;
2677 struct net *net = seq_file_net(seq);
2678 loff_t idx = 0;
2679 unsigned int h;
2680
2681 for (h = 0; h < FIB_TABLE_HASHSZ; h++) {
2682 struct hlist_head *head = &net->ipv4.fib_table_hash[h];
2683 struct fib_table *tb;
2684
2685 hlist_for_each_entry_rcu(tb, head, tb_hlist) {
2686 struct key_vector *n;
2687
2688 for (n = fib_trie_get_first(iter,
2689 (struct trie *) tb->tb_data);
2690 n; n = fib_trie_get_next(iter))
2691 if (pos == idx++) {
2692 iter->tb = tb;
2693 return n;
2694 }
2695 }
2696 }
2697
2698 return NULL;
2699}
2700
2701static void *fib_trie_seq_start(struct seq_file *seq, loff_t *pos)
2702 __acquires(RCU)
2703{
2704 rcu_read_lock();
2705 return fib_trie_get_idx(seq, *pos);
2706}
2707
2708static void *fib_trie_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2709{
2710 struct fib_trie_iter *iter = seq->private;
2711 struct net *net = seq_file_net(seq);
2712 struct fib_table *tb = iter->tb;
2713 struct hlist_node *tb_node;
2714 unsigned int h;
2715 struct key_vector *n;
2716
2717 ++*pos;
2718 /* next node in same table */
2719 n = fib_trie_get_next(iter);
2720 if (n)
2721 return n;
2722
2723 /* walk rest of this hash chain */
2724 h = tb->tb_id & (FIB_TABLE_HASHSZ - 1);
2725 while ((tb_node = rcu_dereference(hlist_next_rcu(&tb->tb_hlist)))) {
2726 tb = hlist_entry(tb_node, struct fib_table, tb_hlist);
2727 n = fib_trie_get_first(iter, (struct trie *) tb->tb_data);
2728 if (n)
2729 goto found;
2730 }
2731
2732 /* new hash chain */
2733 while (++h < FIB_TABLE_HASHSZ) {
2734 struct hlist_head *head = &net->ipv4.fib_table_hash[h];
2735 hlist_for_each_entry_rcu(tb, head, tb_hlist) {
2736 n = fib_trie_get_first(iter, (struct trie *) tb->tb_data);
2737 if (n)
2738 goto found;
2739 }
2740 }
2741 return NULL;
2742
2743found:
2744 iter->tb = tb;
2745 return n;
2746}
2747
2748static void fib_trie_seq_stop(struct seq_file *seq, void *v)
2749 __releases(RCU)
2750{
2751 rcu_read_unlock();
2752}
2753
2754static void seq_indent(struct seq_file *seq, int n)
2755{
2756 while (n-- > 0)
2757 seq_puts(seq, " ");
2758}
2759
2760static inline const char *rtn_scope(char *buf, size_t len, enum rt_scope_t s)
2761{
2762 switch (s) {
2763 case RT_SCOPE_UNIVERSE: return "universe";
2764 case RT_SCOPE_SITE: return "site";
2765 case RT_SCOPE_LINK: return "link";
2766 case RT_SCOPE_HOST: return "host";
2767 case RT_SCOPE_NOWHERE: return "nowhere";
2768 default:
2769 snprintf(buf, len, "scope=%d", s);
2770 return buf;
2771 }
2772}
2773
2774static const char *const rtn_type_names[__RTN_MAX] = {
2775 [RTN_UNSPEC] = "UNSPEC",
2776 [RTN_UNICAST] = "UNICAST",
2777 [RTN_LOCAL] = "LOCAL",
2778 [RTN_BROADCAST] = "BROADCAST",
2779 [RTN_ANYCAST] = "ANYCAST",
2780 [RTN_MULTICAST] = "MULTICAST",
2781 [RTN_BLACKHOLE] = "BLACKHOLE",
2782 [RTN_UNREACHABLE] = "UNREACHABLE",
2783 [RTN_PROHIBIT] = "PROHIBIT",
2784 [RTN_THROW] = "THROW",
2785 [RTN_NAT] = "NAT",
2786 [RTN_XRESOLVE] = "XRESOLVE",
2787};
2788
2789static inline const char *rtn_type(char *buf, size_t len, unsigned int t)
2790{
2791 if (t < __RTN_MAX && rtn_type_names[t])
2792 return rtn_type_names[t];
2793 snprintf(buf, len, "type %u", t);
2794 return buf;
2795}
2796
2797/* Pretty print the trie */
2798static int fib_trie_seq_show(struct seq_file *seq, void *v)
2799{
2800 const struct fib_trie_iter *iter = seq->private;
2801 struct key_vector *n = v;
2802
2803 if (IS_TRIE(node_parent_rcu(n)))
2804 fib_table_print(seq, iter->tb);
2805
2806 if (IS_TNODE(n)) {
2807 __be32 prf = htonl(n->key);
2808
2809 seq_indent(seq, iter->depth-1);
2810 seq_printf(seq, " +-- %pI4/%zu %u %u %u\n",
2811 &prf, KEYLENGTH - n->pos - n->bits, n->bits,
2812 tn_info(n)->full_children,
2813 tn_info(n)->empty_children);
2814 } else {
2815 __be32 val = htonl(n->key);
2816 struct fib_alias *fa;
2817
2818 seq_indent(seq, iter->depth);
2819 seq_printf(seq, " |-- %pI4\n", &val);
2820
2821 hlist_for_each_entry_rcu(fa, &n->leaf, fa_list) {
2822 char buf1[32], buf2[32];
2823
2824 seq_indent(seq, iter->depth + 1);
2825 seq_printf(seq, " /%zu %s %s",
2826 KEYLENGTH - fa->fa_slen,
2827 rtn_scope(buf1, sizeof(buf1),
2828 fa->fa_info->fib_scope),
2829 rtn_type(buf2, sizeof(buf2),
2830 fa->fa_type));
2831 if (fa->fa_dscp)
2832 seq_printf(seq, " tos=%d",
2833 inet_dscp_to_dsfield(fa->fa_dscp));
2834 seq_putc(seq, '\n');
2835 }
2836 }
2837
2838 return 0;
2839}
2840
2841static const struct seq_operations fib_trie_seq_ops = {
2842 .start = fib_trie_seq_start,
2843 .next = fib_trie_seq_next,
2844 .stop = fib_trie_seq_stop,
2845 .show = fib_trie_seq_show,
2846};
2847
2848struct fib_route_iter {
2849 struct seq_net_private p;
2850 struct fib_table *main_tb;
2851 struct key_vector *tnode;
2852 loff_t pos;
2853 t_key key;
2854};
2855
2856static struct key_vector *fib_route_get_idx(struct fib_route_iter *iter,
2857 loff_t pos)
2858{
2859 struct key_vector *l, **tp = &iter->tnode;
2860 t_key key;
2861
2862 /* use cached location of previously found key */
2863 if (iter->pos > 0 && pos >= iter->pos) {
2864 key = iter->key;
2865 } else {
2866 iter->pos = 1;
2867 key = 0;
2868 }
2869
2870 pos -= iter->pos;
2871
2872 while ((l = leaf_walk_rcu(tp, key)) && (pos-- > 0)) {
2873 key = l->key + 1;
2874 iter->pos++;
2875 l = NULL;
2876
2877 /* handle unlikely case of a key wrap */
2878 if (!key)
2879 break;
2880 }
2881
2882 if (l)
2883 iter->key = l->key; /* remember it */
2884 else
2885 iter->pos = 0; /* forget it */
2886
2887 return l;
2888}
2889
2890static void *fib_route_seq_start(struct seq_file *seq, loff_t *pos)
2891 __acquires(RCU)
2892{
2893 struct fib_route_iter *iter = seq->private;
2894 struct fib_table *tb;
2895 struct trie *t;
2896
2897 rcu_read_lock();
2898
2899 tb = fib_get_table(seq_file_net(seq), RT_TABLE_MAIN);
2900 if (!tb)
2901 return NULL;
2902
2903 iter->main_tb = tb;
2904 t = (struct trie *)tb->tb_data;
2905 iter->tnode = t->kv;
2906
2907 if (*pos != 0)
2908 return fib_route_get_idx(iter, *pos);
2909
2910 iter->pos = 0;
2911 iter->key = KEY_MAX;
2912
2913 return SEQ_START_TOKEN;
2914}
2915
2916static void *fib_route_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2917{
2918 struct fib_route_iter *iter = seq->private;
2919 struct key_vector *l = NULL;
2920 t_key key = iter->key + 1;
2921
2922 ++*pos;
2923
2924 /* only allow key of 0 for start of sequence */
2925 if ((v == SEQ_START_TOKEN) || key)
2926 l = leaf_walk_rcu(&iter->tnode, key);
2927
2928 if (l) {
2929 iter->key = l->key;
2930 iter->pos++;
2931 } else {
2932 iter->pos = 0;
2933 }
2934
2935 return l;
2936}
2937
2938static void fib_route_seq_stop(struct seq_file *seq, void *v)
2939 __releases(RCU)
2940{
2941 rcu_read_unlock();
2942}
2943
2944static unsigned int fib_flag_trans(int type, __be32 mask, struct fib_info *fi)
2945{
2946 unsigned int flags = 0;
2947
2948 if (type == RTN_UNREACHABLE || type == RTN_PROHIBIT)
2949 flags = RTF_REJECT;
2950 if (fi) {
2951 const struct fib_nh_common *nhc = fib_info_nhc(fi, 0);
2952
2953 if (nhc->nhc_gw.ipv4)
2954 flags |= RTF_GATEWAY;
2955 }
2956 if (mask == htonl(0xFFFFFFFF))
2957 flags |= RTF_HOST;
2958 flags |= RTF_UP;
2959 return flags;
2960}
2961
2962/*
2963 * This outputs /proc/net/route.
2964 * The format of the file is not supposed to be changed
2965 * and needs to be same as fib_hash output to avoid breaking
2966 * legacy utilities
2967 */
2968static int fib_route_seq_show(struct seq_file *seq, void *v)
2969{
2970 struct fib_route_iter *iter = seq->private;
2971 struct fib_table *tb = iter->main_tb;
2972 struct fib_alias *fa;
2973 struct key_vector *l = v;
2974 __be32 prefix;
2975
2976 if (v == SEQ_START_TOKEN) {
2977 seq_printf(seq, "%-127s\n", "Iface\tDestination\tGateway "
2978 "\tFlags\tRefCnt\tUse\tMetric\tMask\t\tMTU"
2979 "\tWindow\tIRTT");
2980 return 0;
2981 }
2982
2983 prefix = htonl(l->key);
2984
2985 hlist_for_each_entry_rcu(fa, &l->leaf, fa_list) {
2986 struct fib_info *fi = fa->fa_info;
2987 __be32 mask = inet_make_mask(KEYLENGTH - fa->fa_slen);
2988 unsigned int flags = fib_flag_trans(fa->fa_type, mask, fi);
2989
2990 if ((fa->fa_type == RTN_BROADCAST) ||
2991 (fa->fa_type == RTN_MULTICAST))
2992 continue;
2993
2994 if (fa->tb_id != tb->tb_id)
2995 continue;
2996
2997 seq_setwidth(seq, 127);
2998
2999 if (fi) {
3000 struct fib_nh_common *nhc = fib_info_nhc(fi, 0);
3001 __be32 gw = 0;
3002
3003 if (nhc->nhc_gw_family == AF_INET)
3004 gw = nhc->nhc_gw.ipv4;
3005
3006 seq_printf(seq,
3007 "%s\t%08X\t%08X\t%04X\t%d\t%u\t"
3008 "%d\t%08X\t%d\t%u\t%u",
3009 nhc->nhc_dev ? nhc->nhc_dev->name : "*",
3010 prefix, gw, flags, 0, 0,
3011 fi->fib_priority,
3012 mask,
3013 (fi->fib_advmss ?
3014 fi->fib_advmss + 40 : 0),
3015 fi->fib_window,
3016 fi->fib_rtt >> 3);
3017 } else {
3018 seq_printf(seq,
3019 "*\t%08X\t%08X\t%04X\t%d\t%u\t"
3020 "%d\t%08X\t%d\t%u\t%u",
3021 prefix, 0, flags, 0, 0, 0,
3022 mask, 0, 0, 0);
3023 }
3024 seq_pad(seq, '\n');
3025 }
3026
3027 return 0;
3028}
3029
3030static const struct seq_operations fib_route_seq_ops = {
3031 .start = fib_route_seq_start,
3032 .next = fib_route_seq_next,
3033 .stop = fib_route_seq_stop,
3034 .show = fib_route_seq_show,
3035};
3036
3037int __net_init fib_proc_init(struct net *net)
3038{
3039 if (!proc_create_net("fib_trie", 0444, net->proc_net, &fib_trie_seq_ops,
3040 sizeof(struct fib_trie_iter)))
3041 goto out1;
3042
3043 if (!proc_create_net_single("fib_triestat", 0444, net->proc_net,
3044 fib_triestat_seq_show, NULL))
3045 goto out2;
3046
3047 if (!proc_create_net("route", 0444, net->proc_net, &fib_route_seq_ops,
3048 sizeof(struct fib_route_iter)))
3049 goto out3;
3050
3051 return 0;
3052
3053out3:
3054 remove_proc_entry("fib_triestat", net->proc_net);
3055out2:
3056 remove_proc_entry("fib_trie", net->proc_net);
3057out1:
3058 return -ENOMEM;
3059}
3060
3061void __net_exit fib_proc_exit(struct net *net)
3062{
3063 remove_proc_entry("fib_trie", net->proc_net);
3064 remove_proc_entry("fib_triestat", net->proc_net);
3065 remove_proc_entry("route", net->proc_net);
3066}
3067
3068#endif /* CONFIG_PROC_FS */