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_is_available(&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;
148 h = route4_fastmap_hash(id, iif);
150 spin_lock(&fastmap_lock);
151 if (id == head->fastmap[h].id &&
152 iif == head->fastmap[h].iif &&
153 (f = head->fastmap[h].filter) != NULL) {
154 if (f == ROUTE4_FAILURE) {
155 spin_unlock(&fastmap_lock);
160 spin_unlock(&fastmap_lock);
163 spin_unlock(&fastmap_lock);
165 h = route4_hash_to(id);
168 b = rcu_dereference_bh(head->table[h]);
170 for (f = rcu_dereference_bh(b->ht[route4_hash_from(id)]);
172 f = rcu_dereference_bh(f->next))
174 ROUTE4_APPLY_RESULT();
176 for (f = rcu_dereference_bh(b->ht[route4_hash_iif(iif)]);
178 f = rcu_dereference_bh(f->next))
180 ROUTE4_APPLY_RESULT();
182 for (f = rcu_dereference_bh(b->ht[route4_hash_wild()]);
184 f = rcu_dereference_bh(f->next))
185 ROUTE4_APPLY_RESULT();
194 route4_set_fastmap(head, id, iif, ROUTE4_FAILURE);
199 if (id && (TC_H_MAJ(id) == 0 ||
200 !(TC_H_MAJ(id^tp->q->handle)))) {
208 static inline u32 to_hash(u32 id)
217 static inline u32 from_hash(u32 id)
222 if (!(id & 0x8000)) {
227 return 16 + (id & 0xF);
230 static unsigned long route4_get(struct tcf_proto *tp, u32 handle)
232 struct route4_head *head = rtnl_dereference(tp->root);
233 struct route4_bucket *b;
234 struct route4_filter *f;
240 h1 = to_hash(handle);
244 h2 = from_hash(handle >> 16);
248 b = rtnl_dereference(head->table[h1]);
250 for (f = rtnl_dereference(b->ht[h2]);
252 f = rtnl_dereference(f->next))
253 if (f->handle == handle)
254 return (unsigned long)f;
259 static int route4_init(struct tcf_proto *tp)
265 route4_delete_filter(struct rcu_head *head)
267 struct route4_filter *f = container_of(head, struct route4_filter, rcu);
269 tcf_exts_destroy(&f->exts);
273 static void route4_destroy(struct tcf_proto *tp)
275 struct route4_head *head = rtnl_dereference(tp->root);
281 for (h1 = 0; h1 <= 256; h1++) {
282 struct route4_bucket *b;
284 b = rtnl_dereference(head->table[h1]);
286 for (h2 = 0; h2 <= 32; h2++) {
287 struct route4_filter *f;
289 while ((f = rtnl_dereference(b->ht[h2])) != NULL) {
290 struct route4_filter *next;
292 next = rtnl_dereference(f->next);
293 RCU_INIT_POINTER(b->ht[h2], next);
294 tcf_unbind_filter(tp, &f->res);
295 call_rcu(&f->rcu, route4_delete_filter);
298 RCU_INIT_POINTER(head->table[h1], NULL);
302 RCU_INIT_POINTER(tp->root, NULL);
303 kfree_rcu(head, rcu);
306 static int route4_delete(struct tcf_proto *tp, unsigned long arg)
308 struct route4_head *head = rtnl_dereference(tp->root);
309 struct route4_filter *f = (struct route4_filter *)arg;
310 struct route4_filter __rcu **fp;
311 struct route4_filter *nf;
312 struct route4_bucket *b;
322 fp = &b->ht[from_hash(h >> 16)];
323 for (nf = rtnl_dereference(*fp); nf;
324 fp = &nf->next, nf = rtnl_dereference(*fp)) {
327 RCU_INIT_POINTER(*fp, rtnl_dereference(f->next));
329 /* Remove any fastmap lookups that might ref filter
330 * notice we unlink'd the filter so we can't get it
331 * back in the fastmap.
333 route4_reset_fastmap(head);
336 tcf_unbind_filter(tp, &f->res);
337 call_rcu(&f->rcu, route4_delete_filter);
339 /* Strip RTNL protected tree */
340 for (i = 0; i <= 32; i++) {
341 struct route4_filter *rt;
343 rt = rtnl_dereference(b->ht[i]);
348 /* OK, session has no flows */
349 RCU_INIT_POINTER(head->table[to_hash(h)], NULL);
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,
372 u32 id = 0, to = 0, nhandle = 0x8000;
373 struct route4_filter *fp;
375 struct route4_bucket *b;
378 tcf_exts_init(&e, TCA_ROUTE4_ACT, TCA_ROUTE4_POLICE);
379 err = tcf_exts_validate(net, tp, tb, est, &e, ovr);
384 if (tb[TCA_ROUTE4_TO]) {
385 if (new && handle & 0x8000)
387 to = nla_get_u32(tb[TCA_ROUTE4_TO]);
393 if (tb[TCA_ROUTE4_FROM]) {
394 if (tb[TCA_ROUTE4_IIF])
396 id = nla_get_u32(tb[TCA_ROUTE4_FROM]);
400 } else if (tb[TCA_ROUTE4_IIF]) {
401 id = nla_get_u32(tb[TCA_ROUTE4_IIF]);
404 nhandle |= (id | 0x8000) << 16;
406 nhandle |= 0xFFFF << 16;
409 nhandle |= handle & 0x7F00;
410 if (nhandle != handle)
414 h1 = to_hash(nhandle);
415 b = rtnl_dereference(head->table[h1]);
418 b = kzalloc(sizeof(struct route4_bucket), GFP_KERNEL);
422 rcu_assign_pointer(head->table[h1], b);
424 unsigned int h2 = from_hash(nhandle >> 16);
427 for (fp = rtnl_dereference(b->ht[h2]);
429 fp = rtnl_dereference(fp->next))
430 if (fp->handle == f->handle)
434 if (tb[TCA_ROUTE4_TO])
437 if (tb[TCA_ROUTE4_FROM])
439 else if (tb[TCA_ROUTE4_IIF])
446 if (tb[TCA_ROUTE4_CLASSID]) {
447 f->res.classid = nla_get_u32(tb[TCA_ROUTE4_CLASSID]);
448 tcf_bind_filter(tp, &f->res, base);
451 tcf_exts_change(tp, &f->exts, &e);
455 tcf_exts_destroy(&e);
459 static int route4_change(struct net *net, struct sk_buff *in_skb,
460 struct tcf_proto *tp, unsigned long base,
463 unsigned long *arg, bool ovr)
465 struct route4_head *head = rtnl_dereference(tp->root);
466 struct route4_filter __rcu **fp;
467 struct route4_filter *fold, *f1, *pfp, *f = NULL;
468 struct route4_bucket *b;
469 struct nlattr *opt = tca[TCA_OPTIONS];
470 struct nlattr *tb[TCA_ROUTE4_MAX + 1];
476 return handle ? -EINVAL : 0;
478 err = nla_parse_nested(tb, TCA_ROUTE4_MAX, opt, route4_policy);
482 fold = (struct route4_filter *)*arg;
483 if (fold && handle && fold->handle != handle)
488 head = kzalloc(sizeof(struct route4_head), GFP_KERNEL);
491 rcu_assign_pointer(tp->root, head);
494 f = kzalloc(sizeof(struct route4_filter), GFP_KERNEL);
498 tcf_exts_init(&f->exts, TCA_ROUTE4_ACT, TCA_ROUTE4_POLICE);
503 f->handle = fold->handle;
510 err = route4_set_parms(net, tp, base, f, handle, head, tb,
511 tca[TCA_RATE], new, ovr);
515 h = from_hash(f->handle >> 16);
517 for (pfp = rtnl_dereference(*fp);
518 (f1 = rtnl_dereference(*fp)) != NULL;
520 if (f->handle < f1->handle)
523 netif_keep_dst(qdisc_dev(tp->q));
524 rcu_assign_pointer(f->next, f1);
525 rcu_assign_pointer(*fp, f);
527 if (fold && fold->handle && f->handle != fold->handle) {
528 th = to_hash(fold->handle);
529 h = from_hash(fold->handle >> 16);
530 b = rtnl_dereference(head->table[th]);
533 for (pfp = rtnl_dereference(*fp); pfp;
534 fp = &pfp->next, pfp = rtnl_dereference(*fp)) {
543 route4_reset_fastmap(head);
544 *arg = (unsigned long)f;
546 tcf_unbind_filter(tp, &fold->res);
547 call_rcu(&fold->rcu, route4_delete_filter);
556 static void route4_walk(struct tcf_proto *tp, struct tcf_walker *arg)
558 struct route4_head *head = rtnl_dereference(tp->root);
567 for (h = 0; h <= 256; h++) {
568 struct route4_bucket *b = rtnl_dereference(head->table[h]);
571 for (h1 = 0; h1 <= 32; h1++) {
572 struct route4_filter *f;
574 for (f = rtnl_dereference(b->ht[h1]);
576 f = rtnl_dereference(f->next)) {
577 if (arg->count < arg->skip) {
581 if (arg->fn(tp, (unsigned long)f, arg) < 0) {
592 static int route4_dump(struct net *net, struct tcf_proto *tp, unsigned long fh,
593 struct sk_buff *skb, struct tcmsg *t)
595 struct route4_filter *f = (struct route4_filter *)fh;
602 t->tcm_handle = f->handle;
604 nest = nla_nest_start(skb, TCA_OPTIONS);
606 goto nla_put_failure;
608 if (!(f->handle & 0x8000)) {
610 if (nla_put_u32(skb, TCA_ROUTE4_TO, id))
611 goto nla_put_failure;
613 if (f->handle & 0x80000000) {
614 if ((f->handle >> 16) != 0xFFFF &&
615 nla_put_u32(skb, TCA_ROUTE4_IIF, f->iif))
616 goto nla_put_failure;
619 if (nla_put_u32(skb, TCA_ROUTE4_FROM, id))
620 goto nla_put_failure;
622 if (f->res.classid &&
623 nla_put_u32(skb, TCA_ROUTE4_CLASSID, f->res.classid))
624 goto nla_put_failure;
626 if (tcf_exts_dump(skb, &f->exts) < 0)
627 goto nla_put_failure;
629 nla_nest_end(skb, nest);
631 if (tcf_exts_dump_stats(skb, &f->exts) < 0)
632 goto nla_put_failure;
637 nla_nest_cancel(skb, nest);
641 static struct tcf_proto_ops cls_route4_ops __read_mostly = {
643 .classify = route4_classify,
645 .destroy = route4_destroy,
647 .change = route4_change,
648 .delete = route4_delete,
651 .owner = THIS_MODULE,
654 static int __init init_route4(void)
656 return register_tcf_proto_ops(&cls_route4_ops);
659 static void __exit exit_route4(void)
661 unregister_tcf_proto_ops(&cls_route4_ops);
664 module_init(init_route4)
665 module_exit(exit_route4)
666 MODULE_LICENSE("GPL");