2 * net/sched/cls_route.c ROUTE4 classifier.
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License
6 * as published by the Free Software Foundation; either version
7 * 2 of the License, or (at your option) any later version.
9 * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
12 #include <linux/module.h>
13 #include <linux/slab.h>
14 #include <linux/types.h>
15 #include <linux/kernel.h>
16 #include <linux/string.h>
17 #include <linux/errno.h>
18 #include <linux/skbuff.h>
20 #include <net/route.h>
21 #include <net/netlink.h>
22 #include <net/act_api.h>
23 #include <net/pkt_cls.h>
26 * 1. For now we assume that route tags < 256.
27 * It allows to use direct table lookups, instead of hash tables.
28 * 2. For now we assume that "from TAG" and "fromdev DEV" statements
29 * are mutually exclusive.
30 * 3. "to TAG from ANY" has higher priority, than "to ANY from XXX"
32 struct route4_fastmap {
33 struct route4_filter *filter;
39 struct route4_fastmap fastmap[16];
40 struct route4_bucket __rcu *table[256 + 1];
44 struct route4_bucket {
45 /* 16 FROM buckets + 16 IIF buckets + 1 wildcard bucket */
46 struct route4_filter __rcu *ht[16 + 16 + 1];
50 struct route4_filter {
51 struct route4_filter __rcu *next;
55 struct tcf_result res;
58 struct route4_bucket *bkt;
63 #define ROUTE4_FAILURE ((struct route4_filter *)(-1L))
65 static inline int route4_fastmap_hash(u32 id, int iif)
70 static DEFINE_SPINLOCK(fastmap_lock);
72 route4_reset_fastmap(struct route4_head *head)
74 spin_lock_bh(&fastmap_lock);
75 memset(head->fastmap, 0, sizeof(head->fastmap));
76 spin_unlock_bh(&fastmap_lock);
80 route4_set_fastmap(struct route4_head *head, u32 id, int iif,
81 struct route4_filter *f)
83 int h = route4_fastmap_hash(id, iif);
85 /* fastmap updates must look atomic to aling id, iff, filter */
86 spin_lock_bh(&fastmap_lock);
87 head->fastmap[h].id = id;
88 head->fastmap[h].iif = iif;
89 head->fastmap[h].filter = f;
90 spin_unlock_bh(&fastmap_lock);
93 static inline int route4_hash_to(u32 id)
98 static inline int route4_hash_from(u32 id)
100 return (id >> 16) & 0xF;
103 static inline int route4_hash_iif(int iif)
105 return 16 + ((iif >> 16) & 0xF);
108 static inline int route4_hash_wild(void)
113 #define ROUTE4_APPLY_RESULT() \
116 if (tcf_exts_has_actions(&f->exts)) { \
117 int r = tcf_exts_exec(skb, &f->exts, res); \
123 } else if (!dont_cache) \
124 route4_set_fastmap(head, id, iif, f); \
128 static int route4_classify(struct sk_buff *skb, const struct tcf_proto *tp,
129 struct tcf_result *res)
131 struct route4_head *head = rcu_dereference_bh(tp->root);
132 struct dst_entry *dst;
133 struct route4_bucket *b;
134 struct route4_filter *f;
136 int iif, dont_cache = 0;
146 h = route4_fastmap_hash(id, iif);
148 spin_lock(&fastmap_lock);
149 if (id == head->fastmap[h].id &&
150 iif == head->fastmap[h].iif &&
151 (f = head->fastmap[h].filter) != NULL) {
152 if (f == ROUTE4_FAILURE) {
153 spin_unlock(&fastmap_lock);
158 spin_unlock(&fastmap_lock);
161 spin_unlock(&fastmap_lock);
163 h = route4_hash_to(id);
166 b = rcu_dereference_bh(head->table[h]);
168 for (f = rcu_dereference_bh(b->ht[route4_hash_from(id)]);
170 f = rcu_dereference_bh(f->next))
172 ROUTE4_APPLY_RESULT();
174 for (f = rcu_dereference_bh(b->ht[route4_hash_iif(iif)]);
176 f = rcu_dereference_bh(f->next))
178 ROUTE4_APPLY_RESULT();
180 for (f = rcu_dereference_bh(b->ht[route4_hash_wild()]);
182 f = rcu_dereference_bh(f->next))
183 ROUTE4_APPLY_RESULT();
192 route4_set_fastmap(head, id, iif, ROUTE4_FAILURE);
197 static inline u32 to_hash(u32 id)
206 static inline u32 from_hash(u32 id)
211 if (!(id & 0x8000)) {
216 return 16 + (id & 0xF);
219 static void *route4_get(struct tcf_proto *tp, u32 handle)
221 struct route4_head *head = rtnl_dereference(tp->root);
222 struct route4_bucket *b;
223 struct route4_filter *f;
226 h1 = to_hash(handle);
230 h2 = from_hash(handle >> 16);
234 b = rtnl_dereference(head->table[h1]);
236 for (f = rtnl_dereference(b->ht[h2]);
238 f = rtnl_dereference(f->next))
239 if (f->handle == handle)
245 static int route4_init(struct tcf_proto *tp)
247 struct route4_head *head;
249 head = kzalloc(sizeof(struct route4_head), GFP_KERNEL);
253 rcu_assign_pointer(tp->root, head);
257 static void route4_delete_filter(struct rcu_head *head)
259 struct route4_filter *f = container_of(head, struct route4_filter, rcu);
261 tcf_exts_destroy(&f->exts);
265 static void route4_destroy(struct tcf_proto *tp)
267 struct route4_head *head = rtnl_dereference(tp->root);
273 for (h1 = 0; h1 <= 256; h1++) {
274 struct route4_bucket *b;
276 b = rtnl_dereference(head->table[h1]);
278 for (h2 = 0; h2 <= 32; h2++) {
279 struct route4_filter *f;
281 while ((f = rtnl_dereference(b->ht[h2])) != NULL) {
282 struct route4_filter *next;
284 next = rtnl_dereference(f->next);
285 RCU_INIT_POINTER(b->ht[h2], next);
286 tcf_unbind_filter(tp, &f->res);
287 call_rcu(&f->rcu, route4_delete_filter);
290 RCU_INIT_POINTER(head->table[h1], NULL);
294 kfree_rcu(head, rcu);
297 static int route4_delete(struct tcf_proto *tp, void *arg, bool *last)
299 struct route4_head *head = rtnl_dereference(tp->root);
300 struct route4_filter *f = arg;
301 struct route4_filter __rcu **fp;
302 struct route4_filter *nf;
303 struct route4_bucket *b;
313 fp = &b->ht[from_hash(h >> 16)];
314 for (nf = rtnl_dereference(*fp); nf;
315 fp = &nf->next, nf = rtnl_dereference(*fp)) {
318 RCU_INIT_POINTER(*fp, rtnl_dereference(f->next));
320 /* Remove any fastmap lookups that might ref filter
321 * notice we unlink'd the filter so we can't get it
322 * back in the fastmap.
324 route4_reset_fastmap(head);
327 tcf_unbind_filter(tp, &f->res);
328 call_rcu(&f->rcu, route4_delete_filter);
330 /* Strip RTNL protected tree */
331 for (i = 0; i <= 32; i++) {
332 struct route4_filter *rt;
334 rt = rtnl_dereference(b->ht[i]);
339 /* OK, session has no flows */
340 RCU_INIT_POINTER(head->table[to_hash(h)], NULL);
348 for (h1 = 0; h1 <= 256; h1++) {
349 if (rcu_access_pointer(head->table[h1])) {
358 static const struct nla_policy route4_policy[TCA_ROUTE4_MAX + 1] = {
359 [TCA_ROUTE4_CLASSID] = { .type = NLA_U32 },
360 [TCA_ROUTE4_TO] = { .type = NLA_U32 },
361 [TCA_ROUTE4_FROM] = { .type = NLA_U32 },
362 [TCA_ROUTE4_IIF] = { .type = NLA_U32 },
365 static int route4_set_parms(struct net *net, struct tcf_proto *tp,
366 unsigned long base, struct route4_filter *f,
367 u32 handle, struct route4_head *head,
368 struct nlattr **tb, struct nlattr *est, int new,
371 u32 id = 0, to = 0, nhandle = 0x8000;
372 struct route4_filter *fp;
374 struct route4_bucket *b;
377 err = tcf_exts_validate(net, tp, tb, est, &f->exts, ovr);
381 if (tb[TCA_ROUTE4_TO]) {
382 if (new && handle & 0x8000)
384 to = nla_get_u32(tb[TCA_ROUTE4_TO]);
390 if (tb[TCA_ROUTE4_FROM]) {
391 if (tb[TCA_ROUTE4_IIF])
393 id = nla_get_u32(tb[TCA_ROUTE4_FROM]);
397 } else if (tb[TCA_ROUTE4_IIF]) {
398 id = nla_get_u32(tb[TCA_ROUTE4_IIF]);
401 nhandle |= (id | 0x8000) << 16;
403 nhandle |= 0xFFFF << 16;
406 nhandle |= handle & 0x7F00;
407 if (nhandle != handle)
411 h1 = to_hash(nhandle);
412 b = rtnl_dereference(head->table[h1]);
414 b = kzalloc(sizeof(struct route4_bucket), GFP_KERNEL);
418 rcu_assign_pointer(head->table[h1], b);
420 unsigned int h2 = from_hash(nhandle >> 16);
422 for (fp = rtnl_dereference(b->ht[h2]);
424 fp = rtnl_dereference(fp->next))
425 if (fp->handle == f->handle)
429 if (tb[TCA_ROUTE4_TO])
432 if (tb[TCA_ROUTE4_FROM])
434 else if (tb[TCA_ROUTE4_IIF])
441 if (tb[TCA_ROUTE4_CLASSID]) {
442 f->res.classid = nla_get_u32(tb[TCA_ROUTE4_CLASSID]);
443 tcf_bind_filter(tp, &f->res, base);
449 static int route4_change(struct net *net, struct sk_buff *in_skb,
450 struct tcf_proto *tp, unsigned long base, u32 handle,
451 struct nlattr **tca, void **arg, bool ovr)
453 struct route4_head *head = rtnl_dereference(tp->root);
454 struct route4_filter __rcu **fp;
455 struct route4_filter *fold, *f1, *pfp, *f = NULL;
456 struct route4_bucket *b;
457 struct nlattr *opt = tca[TCA_OPTIONS];
458 struct nlattr *tb[TCA_ROUTE4_MAX + 1];
464 return handle ? -EINVAL : 0;
466 err = nla_parse_nested(tb, TCA_ROUTE4_MAX, opt, route4_policy, NULL);
471 if (fold && handle && fold->handle != handle)
475 f = kzalloc(sizeof(struct route4_filter), GFP_KERNEL);
479 err = tcf_exts_init(&f->exts, TCA_ROUTE4_ACT, TCA_ROUTE4_POLICE);
487 f->handle = fold->handle;
494 err = route4_set_parms(net, tp, base, f, handle, head, tb,
495 tca[TCA_RATE], new, ovr);
499 h = from_hash(f->handle >> 16);
501 for (pfp = rtnl_dereference(*fp);
502 (f1 = rtnl_dereference(*fp)) != NULL;
504 if (f->handle < f1->handle)
507 netif_keep_dst(qdisc_dev(tp->q));
508 rcu_assign_pointer(f->next, f1);
509 rcu_assign_pointer(*fp, f);
511 if (fold && fold->handle && f->handle != fold->handle) {
512 th = to_hash(fold->handle);
513 h = from_hash(fold->handle >> 16);
514 b = rtnl_dereference(head->table[th]);
517 for (pfp = rtnl_dereference(*fp); pfp;
518 fp = &pfp->next, pfp = rtnl_dereference(*fp)) {
527 route4_reset_fastmap(head);
530 tcf_unbind_filter(tp, &fold->res);
531 call_rcu(&fold->rcu, route4_delete_filter);
537 tcf_exts_destroy(&f->exts);
542 static void route4_walk(struct tcf_proto *tp, struct tcf_walker *arg)
544 struct route4_head *head = rtnl_dereference(tp->root);
553 for (h = 0; h <= 256; h++) {
554 struct route4_bucket *b = rtnl_dereference(head->table[h]);
557 for (h1 = 0; h1 <= 32; h1++) {
558 struct route4_filter *f;
560 for (f = rtnl_dereference(b->ht[h1]);
562 f = rtnl_dereference(f->next)) {
563 if (arg->count < arg->skip) {
567 if (arg->fn(tp, f, arg) < 0) {
578 static int route4_dump(struct net *net, struct tcf_proto *tp, void *fh,
579 struct sk_buff *skb, struct tcmsg *t)
581 struct route4_filter *f = fh;
588 t->tcm_handle = f->handle;
590 nest = nla_nest_start(skb, TCA_OPTIONS);
592 goto nla_put_failure;
594 if (!(f->handle & 0x8000)) {
596 if (nla_put_u32(skb, TCA_ROUTE4_TO, id))
597 goto nla_put_failure;
599 if (f->handle & 0x80000000) {
600 if ((f->handle >> 16) != 0xFFFF &&
601 nla_put_u32(skb, TCA_ROUTE4_IIF, f->iif))
602 goto nla_put_failure;
605 if (nla_put_u32(skb, TCA_ROUTE4_FROM, id))
606 goto nla_put_failure;
608 if (f->res.classid &&
609 nla_put_u32(skb, TCA_ROUTE4_CLASSID, f->res.classid))
610 goto nla_put_failure;
612 if (tcf_exts_dump(skb, &f->exts) < 0)
613 goto nla_put_failure;
615 nla_nest_end(skb, nest);
617 if (tcf_exts_dump_stats(skb, &f->exts) < 0)
618 goto nla_put_failure;
623 nla_nest_cancel(skb, nest);
627 static void route4_bind_class(void *fh, u32 classid, unsigned long cl)
629 struct route4_filter *f = fh;
631 if (f && f->res.classid == classid)
635 static struct tcf_proto_ops cls_route4_ops __read_mostly = {
637 .classify = route4_classify,
639 .destroy = route4_destroy,
641 .change = route4_change,
642 .delete = route4_delete,
645 .bind_class = route4_bind_class,
646 .owner = THIS_MODULE,
649 static int __init init_route4(void)
651 return register_tcf_proto_ops(&cls_route4_ops);
654 static void __exit exit_route4(void)
656 unregister_tcf_proto_ops(&cls_route4_ops);
659 module_init(init_route4)
660 module_exit(exit_route4)
661 MODULE_LICENSE("GPL");