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1/*
2 * net/sched/act_api.c Packet action API.
3 *
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.
8 *
9 * Author: Jamal Hadi Salim
10 *
11 *
12 */
13
14#include <linux/types.h>
15#include <linux/kernel.h>
16#include <linux/string.h>
17#include <linux/errno.h>
18#include <linux/slab.h>
19#include <linux/skbuff.h>
20#include <linux/init.h>
21#include <linux/kmod.h>
22#include <linux/err.h>
23#include <linux/module.h>
24#include <net/net_namespace.h>
25#include <net/sock.h>
26#include <net/sch_generic.h>
27#include <net/act_api.h>
28#include <net/netlink.h>
29
30static void free_tcf(struct rcu_head *head)
31{
32 struct tcf_common *p = container_of(head, struct tcf_common, tcfc_rcu);
33
34 free_percpu(p->cpu_bstats);
35 free_percpu(p->cpu_qstats);
36 kfree(p);
37}
38
39static void tcf_hash_destroy(struct tcf_hashinfo *hinfo, struct tc_action *a)
40{
41 struct tcf_common *p = a->priv;
42
43 spin_lock_bh(&hinfo->lock);
44 hlist_del(&p->tcfc_head);
45 spin_unlock_bh(&hinfo->lock);
46 gen_kill_estimator(&p->tcfc_bstats,
47 &p->tcfc_rate_est);
48 /*
49 * gen_estimator est_timer() might access p->tcfc_lock
50 * or bstats, wait a RCU grace period before freeing p
51 */
52 call_rcu(&p->tcfc_rcu, free_tcf);
53}
54
55int __tcf_hash_release(struct tc_action *a, bool bind, bool strict)
56{
57 struct tcf_common *p = a->priv;
58 int ret = 0;
59
60 if (p) {
61 if (bind)
62 p->tcfc_bindcnt--;
63 else if (strict && p->tcfc_bindcnt > 0)
64 return -EPERM;
65
66 p->tcfc_refcnt--;
67 if (p->tcfc_bindcnt <= 0 && p->tcfc_refcnt <= 0) {
68 if (a->ops->cleanup)
69 a->ops->cleanup(a, bind);
70 tcf_hash_destroy(a->hinfo, a);
71 ret = ACT_P_DELETED;
72 }
73 }
74
75 return ret;
76}
77EXPORT_SYMBOL(__tcf_hash_release);
78
79static int tcf_dump_walker(struct tcf_hashinfo *hinfo, struct sk_buff *skb,
80 struct netlink_callback *cb, struct tc_action *a)
81{
82 struct hlist_head *head;
83 struct tcf_common *p;
84 int err = 0, index = -1, i = 0, s_i = 0, n_i = 0;
85 struct nlattr *nest;
86
87 spin_lock_bh(&hinfo->lock);
88
89 s_i = cb->args[0];
90
91 for (i = 0; i < (hinfo->hmask + 1); i++) {
92 head = &hinfo->htab[tcf_hash(i, hinfo->hmask)];
93
94 hlist_for_each_entry_rcu(p, head, tcfc_head) {
95 index++;
96 if (index < s_i)
97 continue;
98 a->priv = p;
99 a->order = n_i;
100
101 nest = nla_nest_start(skb, a->order);
102 if (nest == NULL)
103 goto nla_put_failure;
104 err = tcf_action_dump_1(skb, a, 0, 0);
105 if (err < 0) {
106 index--;
107 nlmsg_trim(skb, nest);
108 goto done;
109 }
110 nla_nest_end(skb, nest);
111 n_i++;
112 if (n_i >= TCA_ACT_MAX_PRIO)
113 goto done;
114 }
115 }
116done:
117 spin_unlock_bh(&hinfo->lock);
118 if (n_i)
119 cb->args[0] += n_i;
120 return n_i;
121
122nla_put_failure:
123 nla_nest_cancel(skb, nest);
124 goto done;
125}
126
127static int tcf_del_walker(struct tcf_hashinfo *hinfo, struct sk_buff *skb,
128 struct tc_action *a)
129{
130 struct hlist_head *head;
131 struct hlist_node *n;
132 struct tcf_common *p;
133 struct nlattr *nest;
134 int i = 0, n_i = 0;
135 int ret = -EINVAL;
136
137 nest = nla_nest_start(skb, a->order);
138 if (nest == NULL)
139 goto nla_put_failure;
140 if (nla_put_string(skb, TCA_KIND, a->ops->kind))
141 goto nla_put_failure;
142 for (i = 0; i < (hinfo->hmask + 1); i++) {
143 head = &hinfo->htab[tcf_hash(i, hinfo->hmask)];
144 hlist_for_each_entry_safe(p, n, head, tcfc_head) {
145 a->priv = p;
146 ret = __tcf_hash_release(a, false, true);
147 if (ret == ACT_P_DELETED) {
148 module_put(a->ops->owner);
149 n_i++;
150 } else if (ret < 0)
151 goto nla_put_failure;
152 }
153 }
154 if (nla_put_u32(skb, TCA_FCNT, n_i))
155 goto nla_put_failure;
156 nla_nest_end(skb, nest);
157
158 return n_i;
159nla_put_failure:
160 nla_nest_cancel(skb, nest);
161 return ret;
162}
163
164int tcf_generic_walker(struct tc_action_net *tn, struct sk_buff *skb,
165 struct netlink_callback *cb, int type,
166 struct tc_action *a)
167{
168 struct tcf_hashinfo *hinfo = tn->hinfo;
169
170 a->hinfo = hinfo;
171
172 if (type == RTM_DELACTION) {
173 return tcf_del_walker(hinfo, skb, a);
174 } else if (type == RTM_GETACTION) {
175 return tcf_dump_walker(hinfo, skb, cb, a);
176 } else {
177 WARN(1, "tcf_generic_walker: unknown action %d\n", type);
178 return -EINVAL;
179 }
180}
181EXPORT_SYMBOL(tcf_generic_walker);
182
183static struct tcf_common *tcf_hash_lookup(u32 index, struct tcf_hashinfo *hinfo)
184{
185 struct tcf_common *p = NULL;
186 struct hlist_head *head;
187
188 spin_lock_bh(&hinfo->lock);
189 head = &hinfo->htab[tcf_hash(index, hinfo->hmask)];
190 hlist_for_each_entry_rcu(p, head, tcfc_head)
191 if (p->tcfc_index == index)
192 break;
193 spin_unlock_bh(&hinfo->lock);
194
195 return p;
196}
197
198u32 tcf_hash_new_index(struct tc_action_net *tn)
199{
200 struct tcf_hashinfo *hinfo = tn->hinfo;
201 u32 val = hinfo->index;
202
203 do {
204 if (++val == 0)
205 val = 1;
206 } while (tcf_hash_lookup(val, hinfo));
207
208 hinfo->index = val;
209 return val;
210}
211EXPORT_SYMBOL(tcf_hash_new_index);
212
213int tcf_hash_search(struct tc_action_net *tn, struct tc_action *a, u32 index)
214{
215 struct tcf_hashinfo *hinfo = tn->hinfo;
216 struct tcf_common *p = tcf_hash_lookup(index, hinfo);
217
218 if (p) {
219 a->priv = p;
220 a->hinfo = hinfo;
221 return 1;
222 }
223 return 0;
224}
225EXPORT_SYMBOL(tcf_hash_search);
226
227int tcf_hash_check(struct tc_action_net *tn, u32 index, struct tc_action *a,
228 int bind)
229{
230 struct tcf_hashinfo *hinfo = tn->hinfo;
231 struct tcf_common *p = NULL;
232 if (index && (p = tcf_hash_lookup(index, hinfo)) != NULL) {
233 if (bind)
234 p->tcfc_bindcnt++;
235 p->tcfc_refcnt++;
236 a->priv = p;
237 a->hinfo = hinfo;
238 return 1;
239 }
240 return 0;
241}
242EXPORT_SYMBOL(tcf_hash_check);
243
244void tcf_hash_cleanup(struct tc_action *a, struct nlattr *est)
245{
246 struct tcf_common *pc = a->priv;
247 if (est)
248 gen_kill_estimator(&pc->tcfc_bstats,
249 &pc->tcfc_rate_est);
250 call_rcu(&pc->tcfc_rcu, free_tcf);
251}
252EXPORT_SYMBOL(tcf_hash_cleanup);
253
254int tcf_hash_create(struct tc_action_net *tn, u32 index, struct nlattr *est,
255 struct tc_action *a, int size, int bind, bool cpustats)
256{
257 struct tcf_common *p = kzalloc(size, GFP_KERNEL);
258 struct tcf_hashinfo *hinfo = tn->hinfo;
259 int err = -ENOMEM;
260
261 if (unlikely(!p))
262 return -ENOMEM;
263 p->tcfc_refcnt = 1;
264 if (bind)
265 p->tcfc_bindcnt = 1;
266
267 if (cpustats) {
268 p->cpu_bstats = netdev_alloc_pcpu_stats(struct gnet_stats_basic_cpu);
269 if (!p->cpu_bstats) {
270err1:
271 kfree(p);
272 return err;
273 }
274 p->cpu_qstats = alloc_percpu(struct gnet_stats_queue);
275 if (!p->cpu_qstats) {
276err2:
277 free_percpu(p->cpu_bstats);
278 goto err1;
279 }
280 }
281 spin_lock_init(&p->tcfc_lock);
282 INIT_HLIST_NODE(&p->tcfc_head);
283 p->tcfc_index = index ? index : tcf_hash_new_index(tn);
284 p->tcfc_tm.install = jiffies;
285 p->tcfc_tm.lastuse = jiffies;
286 if (est) {
287 err = gen_new_estimator(&p->tcfc_bstats, p->cpu_bstats,
288 &p->tcfc_rate_est,
289 &p->tcfc_lock, est);
290 if (err) {
291 free_percpu(p->cpu_qstats);
292 goto err2;
293 }
294 }
295
296 a->priv = (void *) p;
297 a->hinfo = hinfo;
298 return 0;
299}
300EXPORT_SYMBOL(tcf_hash_create);
301
302void tcf_hash_insert(struct tc_action_net *tn, struct tc_action *a)
303{
304 struct tcf_common *p = a->priv;
305 struct tcf_hashinfo *hinfo = tn->hinfo;
306 unsigned int h = tcf_hash(p->tcfc_index, hinfo->hmask);
307
308 spin_lock_bh(&hinfo->lock);
309 hlist_add_head(&p->tcfc_head, &hinfo->htab[h]);
310 spin_unlock_bh(&hinfo->lock);
311}
312EXPORT_SYMBOL(tcf_hash_insert);
313
314void tcf_hashinfo_destroy(const struct tc_action_ops *ops,
315 struct tcf_hashinfo *hinfo)
316{
317 struct tc_action a = {
318 .ops = ops,
319 .hinfo = hinfo,
320 };
321 int i;
322
323 for (i = 0; i < hinfo->hmask + 1; i++) {
324 struct tcf_common *p;
325 struct hlist_node *n;
326
327 hlist_for_each_entry_safe(p, n, &hinfo->htab[i], tcfc_head) {
328 int ret;
329
330 a.priv = p;
331 ret = __tcf_hash_release(&a, false, true);
332 if (ret == ACT_P_DELETED)
333 module_put(ops->owner);
334 else if (ret < 0)
335 return;
336 }
337 }
338 kfree(hinfo->htab);
339}
340EXPORT_SYMBOL(tcf_hashinfo_destroy);
341
342static LIST_HEAD(act_base);
343static DEFINE_RWLOCK(act_mod_lock);
344
345int tcf_register_action(struct tc_action_ops *act,
346 struct pernet_operations *ops)
347{
348 struct tc_action_ops *a;
349 int ret;
350
351 if (!act->act || !act->dump || !act->init || !act->walk || !act->lookup)
352 return -EINVAL;
353
354 write_lock(&act_mod_lock);
355 list_for_each_entry(a, &act_base, head) {
356 if (act->type == a->type || (strcmp(act->kind, a->kind) == 0)) {
357 write_unlock(&act_mod_lock);
358 return -EEXIST;
359 }
360 }
361 list_add_tail(&act->head, &act_base);
362 write_unlock(&act_mod_lock);
363
364 ret = register_pernet_subsys(ops);
365 if (ret) {
366 tcf_unregister_action(act, ops);
367 return ret;
368 }
369
370 return 0;
371}
372EXPORT_SYMBOL(tcf_register_action);
373
374int tcf_unregister_action(struct tc_action_ops *act,
375 struct pernet_operations *ops)
376{
377 struct tc_action_ops *a;
378 int err = -ENOENT;
379
380 unregister_pernet_subsys(ops);
381
382 write_lock(&act_mod_lock);
383 list_for_each_entry(a, &act_base, head) {
384 if (a == act) {
385 list_del(&act->head);
386 err = 0;
387 break;
388 }
389 }
390 write_unlock(&act_mod_lock);
391 return err;
392}
393EXPORT_SYMBOL(tcf_unregister_action);
394
395/* lookup by name */
396static struct tc_action_ops *tc_lookup_action_n(char *kind)
397{
398 struct tc_action_ops *a, *res = NULL;
399
400 if (kind) {
401 read_lock(&act_mod_lock);
402 list_for_each_entry(a, &act_base, head) {
403 if (strcmp(kind, a->kind) == 0) {
404 if (try_module_get(a->owner))
405 res = a;
406 break;
407 }
408 }
409 read_unlock(&act_mod_lock);
410 }
411 return res;
412}
413
414/* lookup by nlattr */
415static struct tc_action_ops *tc_lookup_action(struct nlattr *kind)
416{
417 struct tc_action_ops *a, *res = NULL;
418
419 if (kind) {
420 read_lock(&act_mod_lock);
421 list_for_each_entry(a, &act_base, head) {
422 if (nla_strcmp(kind, a->kind) == 0) {
423 if (try_module_get(a->owner))
424 res = a;
425 break;
426 }
427 }
428 read_unlock(&act_mod_lock);
429 }
430 return res;
431}
432
433int tcf_action_exec(struct sk_buff *skb, const struct list_head *actions,
434 struct tcf_result *res)
435{
436 const struct tc_action *a;
437 int ret = -1;
438
439 if (skb->tc_verd & TC_NCLS) {
440 skb->tc_verd = CLR_TC_NCLS(skb->tc_verd);
441 ret = TC_ACT_OK;
442 goto exec_done;
443 }
444 list_for_each_entry(a, actions, list) {
445repeat:
446 ret = a->ops->act(skb, a, res);
447 if (ret == TC_ACT_REPEAT)
448 goto repeat; /* we need a ttl - JHS */
449 if (ret != TC_ACT_PIPE)
450 goto exec_done;
451 }
452exec_done:
453 return ret;
454}
455EXPORT_SYMBOL(tcf_action_exec);
456
457int tcf_action_destroy(struct list_head *actions, int bind)
458{
459 struct tc_action *a, *tmp;
460 int ret = 0;
461
462 list_for_each_entry_safe(a, tmp, actions, list) {
463 ret = __tcf_hash_release(a, bind, true);
464 if (ret == ACT_P_DELETED)
465 module_put(a->ops->owner);
466 else if (ret < 0)
467 return ret;
468 list_del(&a->list);
469 kfree(a);
470 }
471 return ret;
472}
473
474int
475tcf_action_dump_old(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
476{
477 return a->ops->dump(skb, a, bind, ref);
478}
479
480int
481tcf_action_dump_1(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
482{
483 int err = -EINVAL;
484 unsigned char *b = skb_tail_pointer(skb);
485 struct nlattr *nest;
486
487 if (nla_put_string(skb, TCA_KIND, a->ops->kind))
488 goto nla_put_failure;
489 if (tcf_action_copy_stats(skb, a, 0))
490 goto nla_put_failure;
491 nest = nla_nest_start(skb, TCA_OPTIONS);
492 if (nest == NULL)
493 goto nla_put_failure;
494 err = tcf_action_dump_old(skb, a, bind, ref);
495 if (err > 0) {
496 nla_nest_end(skb, nest);
497 return err;
498 }
499
500nla_put_failure:
501 nlmsg_trim(skb, b);
502 return -1;
503}
504EXPORT_SYMBOL(tcf_action_dump_1);
505
506int
507tcf_action_dump(struct sk_buff *skb, struct list_head *actions, int bind, int ref)
508{
509 struct tc_action *a;
510 int err = -EINVAL;
511 struct nlattr *nest;
512
513 list_for_each_entry(a, actions, list) {
514 nest = nla_nest_start(skb, a->order);
515 if (nest == NULL)
516 goto nla_put_failure;
517 err = tcf_action_dump_1(skb, a, bind, ref);
518 if (err < 0)
519 goto errout;
520 nla_nest_end(skb, nest);
521 }
522
523 return 0;
524
525nla_put_failure:
526 err = -EINVAL;
527errout:
528 nla_nest_cancel(skb, nest);
529 return err;
530}
531
532struct tc_action *tcf_action_init_1(struct net *net, struct nlattr *nla,
533 struct nlattr *est, char *name, int ovr,
534 int bind)
535{
536 struct tc_action *a;
537 struct tc_action_ops *a_o;
538 char act_name[IFNAMSIZ];
539 struct nlattr *tb[TCA_ACT_MAX + 1];
540 struct nlattr *kind;
541 int err;
542
543 if (name == NULL) {
544 err = nla_parse_nested(tb, TCA_ACT_MAX, nla, NULL);
545 if (err < 0)
546 goto err_out;
547 err = -EINVAL;
548 kind = tb[TCA_ACT_KIND];
549 if (kind == NULL)
550 goto err_out;
551 if (nla_strlcpy(act_name, kind, IFNAMSIZ) >= IFNAMSIZ)
552 goto err_out;
553 } else {
554 err = -EINVAL;
555 if (strlcpy(act_name, name, IFNAMSIZ) >= IFNAMSIZ)
556 goto err_out;
557 }
558
559 a_o = tc_lookup_action_n(act_name);
560 if (a_o == NULL) {
561#ifdef CONFIG_MODULES
562 rtnl_unlock();
563 request_module("act_%s", act_name);
564 rtnl_lock();
565
566 a_o = tc_lookup_action_n(act_name);
567
568 /* We dropped the RTNL semaphore in order to
569 * perform the module load. So, even if we
570 * succeeded in loading the module we have to
571 * tell the caller to replay the request. We
572 * indicate this using -EAGAIN.
573 */
574 if (a_o != NULL) {
575 err = -EAGAIN;
576 goto err_mod;
577 }
578#endif
579 err = -ENOENT;
580 goto err_out;
581 }
582
583 err = -ENOMEM;
584 a = kzalloc(sizeof(*a), GFP_KERNEL);
585 if (a == NULL)
586 goto err_mod;
587
588 a->ops = a_o;
589 INIT_LIST_HEAD(&a->list);
590 /* backward compatibility for policer */
591 if (name == NULL)
592 err = a_o->init(net, tb[TCA_ACT_OPTIONS], est, a, ovr, bind);
593 else
594 err = a_o->init(net, nla, est, a, ovr, bind);
595 if (err < 0)
596 goto err_free;
597
598 /* module count goes up only when brand new policy is created
599 * if it exists and is only bound to in a_o->init() then
600 * ACT_P_CREATED is not returned (a zero is).
601 */
602 if (err != ACT_P_CREATED)
603 module_put(a_o->owner);
604
605 return a;
606
607err_free:
608 kfree(a);
609err_mod:
610 module_put(a_o->owner);
611err_out:
612 return ERR_PTR(err);
613}
614
615int tcf_action_init(struct net *net, struct nlattr *nla,
616 struct nlattr *est, char *name, int ovr,
617 int bind, struct list_head *actions)
618{
619 struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
620 struct tc_action *act;
621 int err;
622 int i;
623
624 err = nla_parse_nested(tb, TCA_ACT_MAX_PRIO, nla, NULL);
625 if (err < 0)
626 return err;
627
628 for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
629 act = tcf_action_init_1(net, tb[i], est, name, ovr, bind);
630 if (IS_ERR(act)) {
631 err = PTR_ERR(act);
632 goto err;
633 }
634 act->order = i;
635 list_add_tail(&act->list, actions);
636 }
637 return 0;
638
639err:
640 tcf_action_destroy(actions, bind);
641 return err;
642}
643
644int tcf_action_copy_stats(struct sk_buff *skb, struct tc_action *a,
645 int compat_mode)
646{
647 int err = 0;
648 struct gnet_dump d;
649 struct tcf_common *p = a->priv;
650
651 if (p == NULL)
652 goto errout;
653
654 /* compat_mode being true specifies a call that is supposed
655 * to add additional backward compatibility statistic TLVs.
656 */
657 if (compat_mode) {
658 if (a->type == TCA_OLD_COMPAT)
659 err = gnet_stats_start_copy_compat(skb, 0,
660 TCA_STATS, TCA_XSTATS, &p->tcfc_lock, &d);
661 else
662 return 0;
663 } else
664 err = gnet_stats_start_copy(skb, TCA_ACT_STATS,
665 &p->tcfc_lock, &d);
666
667 if (err < 0)
668 goto errout;
669
670 if (gnet_stats_copy_basic(&d, p->cpu_bstats, &p->tcfc_bstats) < 0 ||
671 gnet_stats_copy_rate_est(&d, &p->tcfc_bstats,
672 &p->tcfc_rate_est) < 0 ||
673 gnet_stats_copy_queue(&d, p->cpu_qstats,
674 &p->tcfc_qstats,
675 p->tcfc_qstats.qlen) < 0)
676 goto errout;
677
678 if (gnet_stats_finish_copy(&d) < 0)
679 goto errout;
680
681 return 0;
682
683errout:
684 return -1;
685}
686
687static int
688tca_get_fill(struct sk_buff *skb, struct list_head *actions, u32 portid, u32 seq,
689 u16 flags, int event, int bind, int ref)
690{
691 struct tcamsg *t;
692 struct nlmsghdr *nlh;
693 unsigned char *b = skb_tail_pointer(skb);
694 struct nlattr *nest;
695
696 nlh = nlmsg_put(skb, portid, seq, event, sizeof(*t), flags);
697 if (!nlh)
698 goto out_nlmsg_trim;
699 t = nlmsg_data(nlh);
700 t->tca_family = AF_UNSPEC;
701 t->tca__pad1 = 0;
702 t->tca__pad2 = 0;
703
704 nest = nla_nest_start(skb, TCA_ACT_TAB);
705 if (nest == NULL)
706 goto out_nlmsg_trim;
707
708 if (tcf_action_dump(skb, actions, bind, ref) < 0)
709 goto out_nlmsg_trim;
710
711 nla_nest_end(skb, nest);
712
713 nlh->nlmsg_len = skb_tail_pointer(skb) - b;
714 return skb->len;
715
716out_nlmsg_trim:
717 nlmsg_trim(skb, b);
718 return -1;
719}
720
721static int
722act_get_notify(struct net *net, u32 portid, struct nlmsghdr *n,
723 struct list_head *actions, int event)
724{
725 struct sk_buff *skb;
726
727 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
728 if (!skb)
729 return -ENOBUFS;
730 if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, 0, event, 0, 0) <= 0) {
731 kfree_skb(skb);
732 return -EINVAL;
733 }
734
735 return rtnl_unicast(skb, net, portid);
736}
737
738static struct tc_action *create_a(int i)
739{
740 struct tc_action *act;
741
742 act = kzalloc(sizeof(*act), GFP_KERNEL);
743 if (act == NULL) {
744 pr_debug("create_a: failed to alloc!\n");
745 return NULL;
746 }
747 act->order = i;
748 INIT_LIST_HEAD(&act->list);
749 return act;
750}
751
752static struct tc_action *tcf_action_get_1(struct net *net, struct nlattr *nla,
753 struct nlmsghdr *n, u32 portid)
754{
755 struct nlattr *tb[TCA_ACT_MAX + 1];
756 struct tc_action *a;
757 int index;
758 int err;
759
760 err = nla_parse_nested(tb, TCA_ACT_MAX, nla, NULL);
761 if (err < 0)
762 goto err_out;
763
764 err = -EINVAL;
765 if (tb[TCA_ACT_INDEX] == NULL ||
766 nla_len(tb[TCA_ACT_INDEX]) < sizeof(index))
767 goto err_out;
768 index = nla_get_u32(tb[TCA_ACT_INDEX]);
769
770 err = -ENOMEM;
771 a = create_a(0);
772 if (a == NULL)
773 goto err_out;
774
775 err = -EINVAL;
776 a->ops = tc_lookup_action(tb[TCA_ACT_KIND]);
777 if (a->ops == NULL) /* could happen in batch of actions */
778 goto err_free;
779 err = -ENOENT;
780 if (a->ops->lookup(net, a, index) == 0)
781 goto err_mod;
782
783 module_put(a->ops->owner);
784 return a;
785
786err_mod:
787 module_put(a->ops->owner);
788err_free:
789 kfree(a);
790err_out:
791 return ERR_PTR(err);
792}
793
794static void cleanup_a(struct list_head *actions)
795{
796 struct tc_action *a, *tmp;
797
798 list_for_each_entry_safe(a, tmp, actions, list) {
799 list_del(&a->list);
800 kfree(a);
801 }
802}
803
804static int tca_action_flush(struct net *net, struct nlattr *nla,
805 struct nlmsghdr *n, u32 portid)
806{
807 struct sk_buff *skb;
808 unsigned char *b;
809 struct nlmsghdr *nlh;
810 struct tcamsg *t;
811 struct netlink_callback dcb;
812 struct nlattr *nest;
813 struct nlattr *tb[TCA_ACT_MAX + 1];
814 struct nlattr *kind;
815 struct tc_action a;
816 int err = -ENOMEM;
817
818 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
819 if (!skb) {
820 pr_debug("tca_action_flush: failed skb alloc\n");
821 return err;
822 }
823
824 b = skb_tail_pointer(skb);
825
826 err = nla_parse_nested(tb, TCA_ACT_MAX, nla, NULL);
827 if (err < 0)
828 goto err_out;
829
830 err = -EINVAL;
831 kind = tb[TCA_ACT_KIND];
832 memset(&a, 0, sizeof(struct tc_action));
833 INIT_LIST_HEAD(&a.list);
834 a.ops = tc_lookup_action(kind);
835 if (a.ops == NULL) /*some idjot trying to flush unknown action */
836 goto err_out;
837
838 nlh = nlmsg_put(skb, portid, n->nlmsg_seq, RTM_DELACTION, sizeof(*t), 0);
839 if (!nlh)
840 goto out_module_put;
841 t = nlmsg_data(nlh);
842 t->tca_family = AF_UNSPEC;
843 t->tca__pad1 = 0;
844 t->tca__pad2 = 0;
845
846 nest = nla_nest_start(skb, TCA_ACT_TAB);
847 if (nest == NULL)
848 goto out_module_put;
849
850 err = a.ops->walk(net, skb, &dcb, RTM_DELACTION, &a);
851 if (err < 0)
852 goto out_module_put;
853 if (err == 0)
854 goto noflush_out;
855
856 nla_nest_end(skb, nest);
857
858 nlh->nlmsg_len = skb_tail_pointer(skb) - b;
859 nlh->nlmsg_flags |= NLM_F_ROOT;
860 module_put(a.ops->owner);
861 err = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
862 n->nlmsg_flags & NLM_F_ECHO);
863 if (err > 0)
864 return 0;
865
866 return err;
867
868out_module_put:
869 module_put(a.ops->owner);
870err_out:
871noflush_out:
872 kfree_skb(skb);
873 return err;
874}
875
876static int
877tcf_del_notify(struct net *net, struct nlmsghdr *n, struct list_head *actions,
878 u32 portid)
879{
880 int ret;
881 struct sk_buff *skb;
882
883 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
884 if (!skb)
885 return -ENOBUFS;
886
887 if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, 0, RTM_DELACTION,
888 0, 1) <= 0) {
889 kfree_skb(skb);
890 return -EINVAL;
891 }
892
893 /* now do the delete */
894 ret = tcf_action_destroy(actions, 0);
895 if (ret < 0) {
896 kfree_skb(skb);
897 return ret;
898 }
899
900 ret = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
901 n->nlmsg_flags & NLM_F_ECHO);
902 if (ret > 0)
903 return 0;
904 return ret;
905}
906
907static int
908tca_action_gd(struct net *net, struct nlattr *nla, struct nlmsghdr *n,
909 u32 portid, int event)
910{
911 int i, ret;
912 struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
913 struct tc_action *act;
914 LIST_HEAD(actions);
915
916 ret = nla_parse_nested(tb, TCA_ACT_MAX_PRIO, nla, NULL);
917 if (ret < 0)
918 return ret;
919
920 if (event == RTM_DELACTION && n->nlmsg_flags & NLM_F_ROOT) {
921 if (tb[1] != NULL)
922 return tca_action_flush(net, tb[1], n, portid);
923 else
924 return -EINVAL;
925 }
926
927 for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
928 act = tcf_action_get_1(net, tb[i], n, portid);
929 if (IS_ERR(act)) {
930 ret = PTR_ERR(act);
931 goto err;
932 }
933 act->order = i;
934 list_add_tail(&act->list, &actions);
935 }
936
937 if (event == RTM_GETACTION)
938 ret = act_get_notify(net, portid, n, &actions, event);
939 else { /* delete */
940 ret = tcf_del_notify(net, n, &actions, portid);
941 if (ret)
942 goto err;
943 return ret;
944 }
945err:
946 cleanup_a(&actions);
947 return ret;
948}
949
950static int
951tcf_add_notify(struct net *net, struct nlmsghdr *n, struct list_head *actions,
952 u32 portid)
953{
954 struct sk_buff *skb;
955 int err = 0;
956
957 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
958 if (!skb)
959 return -ENOBUFS;
960
961 if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, n->nlmsg_flags,
962 RTM_NEWACTION, 0, 0) <= 0) {
963 kfree_skb(skb);
964 return -EINVAL;
965 }
966
967 err = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
968 n->nlmsg_flags & NLM_F_ECHO);
969 if (err > 0)
970 err = 0;
971 return err;
972}
973
974static int
975tcf_action_add(struct net *net, struct nlattr *nla, struct nlmsghdr *n,
976 u32 portid, int ovr)
977{
978 int ret = 0;
979 LIST_HEAD(actions);
980
981 ret = tcf_action_init(net, nla, NULL, NULL, ovr, 0, &actions);
982 if (ret)
983 goto done;
984
985 /* dump then free all the actions after update; inserted policy
986 * stays intact
987 */
988 ret = tcf_add_notify(net, n, &actions, portid);
989 cleanup_a(&actions);
990done:
991 return ret;
992}
993
994static int tc_ctl_action(struct sk_buff *skb, struct nlmsghdr *n)
995{
996 struct net *net = sock_net(skb->sk);
997 struct nlattr *tca[TCA_ACT_MAX + 1];
998 u32 portid = skb ? NETLINK_CB(skb).portid : 0;
999 int ret = 0, ovr = 0;
1000
1001 if ((n->nlmsg_type != RTM_GETACTION) && !netlink_capable(skb, CAP_NET_ADMIN))
1002 return -EPERM;
1003
1004 ret = nlmsg_parse(n, sizeof(struct tcamsg), tca, TCA_ACT_MAX, NULL);
1005 if (ret < 0)
1006 return ret;
1007
1008 if (tca[TCA_ACT_TAB] == NULL) {
1009 pr_notice("tc_ctl_action: received NO action attribs\n");
1010 return -EINVAL;
1011 }
1012
1013 /* n->nlmsg_flags & NLM_F_CREATE */
1014 switch (n->nlmsg_type) {
1015 case RTM_NEWACTION:
1016 /* we are going to assume all other flags
1017 * imply create only if it doesn't exist
1018 * Note that CREATE | EXCL implies that
1019 * but since we want avoid ambiguity (eg when flags
1020 * is zero) then just set this
1021 */
1022 if (n->nlmsg_flags & NLM_F_REPLACE)
1023 ovr = 1;
1024replay:
1025 ret = tcf_action_add(net, tca[TCA_ACT_TAB], n, portid, ovr);
1026 if (ret == -EAGAIN)
1027 goto replay;
1028 break;
1029 case RTM_DELACTION:
1030 ret = tca_action_gd(net, tca[TCA_ACT_TAB], n,
1031 portid, RTM_DELACTION);
1032 break;
1033 case RTM_GETACTION:
1034 ret = tca_action_gd(net, tca[TCA_ACT_TAB], n,
1035 portid, RTM_GETACTION);
1036 break;
1037 default:
1038 BUG();
1039 }
1040
1041 return ret;
1042}
1043
1044static struct nlattr *
1045find_dump_kind(const struct nlmsghdr *n)
1046{
1047 struct nlattr *tb1, *tb2[TCA_ACT_MAX + 1];
1048 struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
1049 struct nlattr *nla[TCAA_MAX + 1];
1050 struct nlattr *kind;
1051
1052 if (nlmsg_parse(n, sizeof(struct tcamsg), nla, TCAA_MAX, NULL) < 0)
1053 return NULL;
1054 tb1 = nla[TCA_ACT_TAB];
1055 if (tb1 == NULL)
1056 return NULL;
1057
1058 if (nla_parse(tb, TCA_ACT_MAX_PRIO, nla_data(tb1),
1059 NLMSG_ALIGN(nla_len(tb1)), NULL) < 0)
1060 return NULL;
1061
1062 if (tb[1] == NULL)
1063 return NULL;
1064 if (nla_parse(tb2, TCA_ACT_MAX, nla_data(tb[1]),
1065 nla_len(tb[1]), NULL) < 0)
1066 return NULL;
1067 kind = tb2[TCA_ACT_KIND];
1068
1069 return kind;
1070}
1071
1072static int
1073tc_dump_action(struct sk_buff *skb, struct netlink_callback *cb)
1074{
1075 struct net *net = sock_net(skb->sk);
1076 struct nlmsghdr *nlh;
1077 unsigned char *b = skb_tail_pointer(skb);
1078 struct nlattr *nest;
1079 struct tc_action_ops *a_o;
1080 struct tc_action a;
1081 int ret = 0;
1082 struct tcamsg *t = (struct tcamsg *) nlmsg_data(cb->nlh);
1083 struct nlattr *kind = find_dump_kind(cb->nlh);
1084
1085 if (kind == NULL) {
1086 pr_info("tc_dump_action: action bad kind\n");
1087 return 0;
1088 }
1089
1090 a_o = tc_lookup_action(kind);
1091 if (a_o == NULL)
1092 return 0;
1093
1094 memset(&a, 0, sizeof(struct tc_action));
1095 a.ops = a_o;
1096
1097 nlh = nlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
1098 cb->nlh->nlmsg_type, sizeof(*t), 0);
1099 if (!nlh)
1100 goto out_module_put;
1101 t = nlmsg_data(nlh);
1102 t->tca_family = AF_UNSPEC;
1103 t->tca__pad1 = 0;
1104 t->tca__pad2 = 0;
1105
1106 nest = nla_nest_start(skb, TCA_ACT_TAB);
1107 if (nest == NULL)
1108 goto out_module_put;
1109
1110 ret = a_o->walk(net, skb, cb, RTM_GETACTION, &a);
1111 if (ret < 0)
1112 goto out_module_put;
1113
1114 if (ret > 0) {
1115 nla_nest_end(skb, nest);
1116 ret = skb->len;
1117 } else
1118 nla_nest_cancel(skb, nest);
1119
1120 nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1121 if (NETLINK_CB(cb->skb).portid && ret)
1122 nlh->nlmsg_flags |= NLM_F_MULTI;
1123 module_put(a_o->owner);
1124 return skb->len;
1125
1126out_module_put:
1127 module_put(a_o->owner);
1128 nlmsg_trim(skb, b);
1129 return skb->len;
1130}
1131
1132static int __init tc_action_init(void)
1133{
1134 rtnl_register(PF_UNSPEC, RTM_NEWACTION, tc_ctl_action, NULL, NULL);
1135 rtnl_register(PF_UNSPEC, RTM_DELACTION, tc_ctl_action, NULL, NULL);
1136 rtnl_register(PF_UNSPEC, RTM_GETACTION, tc_ctl_action, tc_dump_action,
1137 NULL);
1138
1139 return 0;
1140}
1141
1142subsys_initcall(tc_action_init);
1/*
2 * net/sched/act_api.c Packet action API.
3 *
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.
8 *
9 * Author: Jamal Hadi Salim
10 *
11 *
12 */
13
14#include <linux/types.h>
15#include <linux/kernel.h>
16#include <linux/string.h>
17#include <linux/errno.h>
18#include <linux/slab.h>
19#include <linux/skbuff.h>
20#include <linux/init.h>
21#include <linux/kmod.h>
22#include <linux/err.h>
23#include <linux/module.h>
24#include <net/net_namespace.h>
25#include <net/sock.h>
26#include <net/sch_generic.h>
27#include <net/act_api.h>
28#include <net/netlink.h>
29
30static void free_tcf(struct rcu_head *head)
31{
32 struct tc_action *p = container_of(head, struct tc_action, tcfa_rcu);
33
34 free_percpu(p->cpu_bstats);
35 free_percpu(p->cpu_qstats);
36 kfree(p);
37}
38
39static void tcf_hash_destroy(struct tcf_hashinfo *hinfo, struct tc_action *p)
40{
41 spin_lock_bh(&hinfo->lock);
42 hlist_del(&p->tcfa_head);
43 spin_unlock_bh(&hinfo->lock);
44 gen_kill_estimator(&p->tcfa_rate_est);
45 /*
46 * gen_estimator est_timer() might access p->tcfa_lock
47 * or bstats, wait a RCU grace period before freeing p
48 */
49 call_rcu(&p->tcfa_rcu, free_tcf);
50}
51
52int __tcf_hash_release(struct tc_action *p, bool bind, bool strict)
53{
54 int ret = 0;
55
56 if (p) {
57 if (bind)
58 p->tcfa_bindcnt--;
59 else if (strict && p->tcfa_bindcnt > 0)
60 return -EPERM;
61
62 p->tcfa_refcnt--;
63 if (p->tcfa_bindcnt <= 0 && p->tcfa_refcnt <= 0) {
64 if (p->ops->cleanup)
65 p->ops->cleanup(p, bind);
66 tcf_hash_destroy(p->hinfo, p);
67 ret = ACT_P_DELETED;
68 }
69 }
70
71 return ret;
72}
73EXPORT_SYMBOL(__tcf_hash_release);
74
75static int tcf_dump_walker(struct tcf_hashinfo *hinfo, struct sk_buff *skb,
76 struct netlink_callback *cb)
77{
78 int err = 0, index = -1, i = 0, s_i = 0, n_i = 0;
79 struct nlattr *nest;
80
81 spin_lock_bh(&hinfo->lock);
82
83 s_i = cb->args[0];
84
85 for (i = 0; i < (hinfo->hmask + 1); i++) {
86 struct hlist_head *head;
87 struct tc_action *p;
88
89 head = &hinfo->htab[tcf_hash(i, hinfo->hmask)];
90
91 hlist_for_each_entry_rcu(p, head, tcfa_head) {
92 index++;
93 if (index < s_i)
94 continue;
95
96 nest = nla_nest_start(skb, n_i);
97 if (nest == NULL)
98 goto nla_put_failure;
99 err = tcf_action_dump_1(skb, p, 0, 0);
100 if (err < 0) {
101 index--;
102 nlmsg_trim(skb, nest);
103 goto done;
104 }
105 nla_nest_end(skb, nest);
106 n_i++;
107 if (n_i >= TCA_ACT_MAX_PRIO)
108 goto done;
109 }
110 }
111done:
112 spin_unlock_bh(&hinfo->lock);
113 if (n_i)
114 cb->args[0] += n_i;
115 return n_i;
116
117nla_put_failure:
118 nla_nest_cancel(skb, nest);
119 goto done;
120}
121
122static int tcf_del_walker(struct tcf_hashinfo *hinfo, struct sk_buff *skb,
123 const struct tc_action_ops *ops)
124{
125 struct nlattr *nest;
126 int i = 0, n_i = 0;
127 int ret = -EINVAL;
128
129 nest = nla_nest_start(skb, 0);
130 if (nest == NULL)
131 goto nla_put_failure;
132 if (nla_put_string(skb, TCA_KIND, ops->kind))
133 goto nla_put_failure;
134 for (i = 0; i < (hinfo->hmask + 1); i++) {
135 struct hlist_head *head;
136 struct hlist_node *n;
137 struct tc_action *p;
138
139 head = &hinfo->htab[tcf_hash(i, hinfo->hmask)];
140 hlist_for_each_entry_safe(p, n, head, tcfa_head) {
141 ret = __tcf_hash_release(p, false, true);
142 if (ret == ACT_P_DELETED) {
143 module_put(p->ops->owner);
144 n_i++;
145 } else if (ret < 0)
146 goto nla_put_failure;
147 }
148 }
149 if (nla_put_u32(skb, TCA_FCNT, n_i))
150 goto nla_put_failure;
151 nla_nest_end(skb, nest);
152
153 return n_i;
154nla_put_failure:
155 nla_nest_cancel(skb, nest);
156 return ret;
157}
158
159int tcf_generic_walker(struct tc_action_net *tn, struct sk_buff *skb,
160 struct netlink_callback *cb, int type,
161 const struct tc_action_ops *ops)
162{
163 struct tcf_hashinfo *hinfo = tn->hinfo;
164
165 if (type == RTM_DELACTION) {
166 return tcf_del_walker(hinfo, skb, ops);
167 } else if (type == RTM_GETACTION) {
168 return tcf_dump_walker(hinfo, skb, cb);
169 } else {
170 WARN(1, "tcf_generic_walker: unknown action %d\n", type);
171 return -EINVAL;
172 }
173}
174EXPORT_SYMBOL(tcf_generic_walker);
175
176static struct tc_action *tcf_hash_lookup(u32 index, struct tcf_hashinfo *hinfo)
177{
178 struct tc_action *p = NULL;
179 struct hlist_head *head;
180
181 spin_lock_bh(&hinfo->lock);
182 head = &hinfo->htab[tcf_hash(index, hinfo->hmask)];
183 hlist_for_each_entry_rcu(p, head, tcfa_head)
184 if (p->tcfa_index == index)
185 break;
186 spin_unlock_bh(&hinfo->lock);
187
188 return p;
189}
190
191u32 tcf_hash_new_index(struct tc_action_net *tn)
192{
193 struct tcf_hashinfo *hinfo = tn->hinfo;
194 u32 val = hinfo->index;
195
196 do {
197 if (++val == 0)
198 val = 1;
199 } while (tcf_hash_lookup(val, hinfo));
200
201 hinfo->index = val;
202 return val;
203}
204EXPORT_SYMBOL(tcf_hash_new_index);
205
206int tcf_hash_search(struct tc_action_net *tn, struct tc_action **a, u32 index)
207{
208 struct tcf_hashinfo *hinfo = tn->hinfo;
209 struct tc_action *p = tcf_hash_lookup(index, hinfo);
210
211 if (p) {
212 *a = p;
213 return 1;
214 }
215 return 0;
216}
217EXPORT_SYMBOL(tcf_hash_search);
218
219bool tcf_hash_check(struct tc_action_net *tn, u32 index, struct tc_action **a,
220 int bind)
221{
222 struct tcf_hashinfo *hinfo = tn->hinfo;
223 struct tc_action *p = NULL;
224
225 if (index && (p = tcf_hash_lookup(index, hinfo)) != NULL) {
226 if (bind)
227 p->tcfa_bindcnt++;
228 p->tcfa_refcnt++;
229 *a = p;
230 return true;
231 }
232 return false;
233}
234EXPORT_SYMBOL(tcf_hash_check);
235
236void tcf_hash_cleanup(struct tc_action *a, struct nlattr *est)
237{
238 if (est)
239 gen_kill_estimator(&a->tcfa_rate_est);
240 call_rcu(&a->tcfa_rcu, free_tcf);
241}
242EXPORT_SYMBOL(tcf_hash_cleanup);
243
244int tcf_hash_create(struct tc_action_net *tn, u32 index, struct nlattr *est,
245 struct tc_action **a, const struct tc_action_ops *ops,
246 int bind, bool cpustats)
247{
248 struct tc_action *p = kzalloc(ops->size, GFP_KERNEL);
249 struct tcf_hashinfo *hinfo = tn->hinfo;
250 int err = -ENOMEM;
251
252 if (unlikely(!p))
253 return -ENOMEM;
254 p->tcfa_refcnt = 1;
255 if (bind)
256 p->tcfa_bindcnt = 1;
257
258 if (cpustats) {
259 p->cpu_bstats = netdev_alloc_pcpu_stats(struct gnet_stats_basic_cpu);
260 if (!p->cpu_bstats) {
261err1:
262 kfree(p);
263 return err;
264 }
265 p->cpu_qstats = alloc_percpu(struct gnet_stats_queue);
266 if (!p->cpu_qstats) {
267err2:
268 free_percpu(p->cpu_bstats);
269 goto err1;
270 }
271 }
272 spin_lock_init(&p->tcfa_lock);
273 INIT_HLIST_NODE(&p->tcfa_head);
274 p->tcfa_index = index ? index : tcf_hash_new_index(tn);
275 p->tcfa_tm.install = jiffies;
276 p->tcfa_tm.lastuse = jiffies;
277 p->tcfa_tm.firstuse = 0;
278 if (est) {
279 err = gen_new_estimator(&p->tcfa_bstats, p->cpu_bstats,
280 &p->tcfa_rate_est,
281 &p->tcfa_lock, NULL, est);
282 if (err) {
283 free_percpu(p->cpu_qstats);
284 goto err2;
285 }
286 }
287
288 p->hinfo = hinfo;
289 p->ops = ops;
290 INIT_LIST_HEAD(&p->list);
291 *a = p;
292 return 0;
293}
294EXPORT_SYMBOL(tcf_hash_create);
295
296void tcf_hash_insert(struct tc_action_net *tn, struct tc_action *a)
297{
298 struct tcf_hashinfo *hinfo = tn->hinfo;
299 unsigned int h = tcf_hash(a->tcfa_index, hinfo->hmask);
300
301 spin_lock_bh(&hinfo->lock);
302 hlist_add_head(&a->tcfa_head, &hinfo->htab[h]);
303 spin_unlock_bh(&hinfo->lock);
304}
305EXPORT_SYMBOL(tcf_hash_insert);
306
307void tcf_hashinfo_destroy(const struct tc_action_ops *ops,
308 struct tcf_hashinfo *hinfo)
309{
310 int i;
311
312 for (i = 0; i < hinfo->hmask + 1; i++) {
313 struct tc_action *p;
314 struct hlist_node *n;
315
316 hlist_for_each_entry_safe(p, n, &hinfo->htab[i], tcfa_head) {
317 int ret;
318
319 ret = __tcf_hash_release(p, false, true);
320 if (ret == ACT_P_DELETED)
321 module_put(ops->owner);
322 else if (ret < 0)
323 return;
324 }
325 }
326 kfree(hinfo->htab);
327}
328EXPORT_SYMBOL(tcf_hashinfo_destroy);
329
330static LIST_HEAD(act_base);
331static DEFINE_RWLOCK(act_mod_lock);
332
333int tcf_register_action(struct tc_action_ops *act,
334 struct pernet_operations *ops)
335{
336 struct tc_action_ops *a;
337 int ret;
338
339 if (!act->act || !act->dump || !act->init || !act->walk || !act->lookup)
340 return -EINVAL;
341
342 /* We have to register pernet ops before making the action ops visible,
343 * otherwise tcf_action_init_1() could get a partially initialized
344 * netns.
345 */
346 ret = register_pernet_subsys(ops);
347 if (ret)
348 return ret;
349
350 write_lock(&act_mod_lock);
351 list_for_each_entry(a, &act_base, head) {
352 if (act->type == a->type || (strcmp(act->kind, a->kind) == 0)) {
353 write_unlock(&act_mod_lock);
354 unregister_pernet_subsys(ops);
355 return -EEXIST;
356 }
357 }
358 list_add_tail(&act->head, &act_base);
359 write_unlock(&act_mod_lock);
360
361 return 0;
362}
363EXPORT_SYMBOL(tcf_register_action);
364
365int tcf_unregister_action(struct tc_action_ops *act,
366 struct pernet_operations *ops)
367{
368 struct tc_action_ops *a;
369 int err = -ENOENT;
370
371 write_lock(&act_mod_lock);
372 list_for_each_entry(a, &act_base, head) {
373 if (a == act) {
374 list_del(&act->head);
375 err = 0;
376 break;
377 }
378 }
379 write_unlock(&act_mod_lock);
380 if (!err)
381 unregister_pernet_subsys(ops);
382 return err;
383}
384EXPORT_SYMBOL(tcf_unregister_action);
385
386/* lookup by name */
387static struct tc_action_ops *tc_lookup_action_n(char *kind)
388{
389 struct tc_action_ops *a, *res = NULL;
390
391 if (kind) {
392 read_lock(&act_mod_lock);
393 list_for_each_entry(a, &act_base, head) {
394 if (strcmp(kind, a->kind) == 0) {
395 if (try_module_get(a->owner))
396 res = a;
397 break;
398 }
399 }
400 read_unlock(&act_mod_lock);
401 }
402 return res;
403}
404
405/* lookup by nlattr */
406static struct tc_action_ops *tc_lookup_action(struct nlattr *kind)
407{
408 struct tc_action_ops *a, *res = NULL;
409
410 if (kind) {
411 read_lock(&act_mod_lock);
412 list_for_each_entry(a, &act_base, head) {
413 if (nla_strcmp(kind, a->kind) == 0) {
414 if (try_module_get(a->owner))
415 res = a;
416 break;
417 }
418 }
419 read_unlock(&act_mod_lock);
420 }
421 return res;
422}
423
424int tcf_action_exec(struct sk_buff *skb, struct tc_action **actions,
425 int nr_actions, struct tcf_result *res)
426{
427 int ret = -1, i;
428
429 if (skb->tc_verd & TC_NCLS) {
430 skb->tc_verd = CLR_TC_NCLS(skb->tc_verd);
431 ret = TC_ACT_OK;
432 goto exec_done;
433 }
434 for (i = 0; i < nr_actions; i++) {
435 const struct tc_action *a = actions[i];
436
437repeat:
438 ret = a->ops->act(skb, a, res);
439 if (ret == TC_ACT_REPEAT)
440 goto repeat; /* we need a ttl - JHS */
441 if (ret != TC_ACT_PIPE)
442 goto exec_done;
443 }
444exec_done:
445 return ret;
446}
447EXPORT_SYMBOL(tcf_action_exec);
448
449int tcf_action_destroy(struct list_head *actions, int bind)
450{
451 struct tc_action *a, *tmp;
452 int ret = 0;
453
454 list_for_each_entry_safe(a, tmp, actions, list) {
455 ret = __tcf_hash_release(a, bind, true);
456 if (ret == ACT_P_DELETED)
457 module_put(a->ops->owner);
458 else if (ret < 0)
459 return ret;
460 }
461 return ret;
462}
463
464int
465tcf_action_dump_old(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
466{
467 return a->ops->dump(skb, a, bind, ref);
468}
469
470int
471tcf_action_dump_1(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
472{
473 int err = -EINVAL;
474 unsigned char *b = skb_tail_pointer(skb);
475 struct nlattr *nest;
476
477 if (nla_put_string(skb, TCA_KIND, a->ops->kind))
478 goto nla_put_failure;
479 if (tcf_action_copy_stats(skb, a, 0))
480 goto nla_put_failure;
481 nest = nla_nest_start(skb, TCA_OPTIONS);
482 if (nest == NULL)
483 goto nla_put_failure;
484 err = tcf_action_dump_old(skb, a, bind, ref);
485 if (err > 0) {
486 nla_nest_end(skb, nest);
487 return err;
488 }
489
490nla_put_failure:
491 nlmsg_trim(skb, b);
492 return -1;
493}
494EXPORT_SYMBOL(tcf_action_dump_1);
495
496int tcf_action_dump(struct sk_buff *skb, struct list_head *actions,
497 int bind, int ref)
498{
499 struct tc_action *a;
500 int err = -EINVAL;
501 struct nlattr *nest;
502
503 list_for_each_entry(a, actions, list) {
504 nest = nla_nest_start(skb, a->order);
505 if (nest == NULL)
506 goto nla_put_failure;
507 err = tcf_action_dump_1(skb, a, bind, ref);
508 if (err < 0)
509 goto errout;
510 nla_nest_end(skb, nest);
511 }
512
513 return 0;
514
515nla_put_failure:
516 err = -EINVAL;
517errout:
518 nla_nest_cancel(skb, nest);
519 return err;
520}
521
522struct tc_action *tcf_action_init_1(struct net *net, struct nlattr *nla,
523 struct nlattr *est, char *name, int ovr,
524 int bind)
525{
526 struct tc_action *a;
527 struct tc_action_ops *a_o;
528 char act_name[IFNAMSIZ];
529 struct nlattr *tb[TCA_ACT_MAX + 1];
530 struct nlattr *kind;
531 int err;
532
533 if (name == NULL) {
534 err = nla_parse_nested(tb, TCA_ACT_MAX, nla, NULL);
535 if (err < 0)
536 goto err_out;
537 err = -EINVAL;
538 kind = tb[TCA_ACT_KIND];
539 if (kind == NULL)
540 goto err_out;
541 if (nla_strlcpy(act_name, kind, IFNAMSIZ) >= IFNAMSIZ)
542 goto err_out;
543 } else {
544 err = -EINVAL;
545 if (strlcpy(act_name, name, IFNAMSIZ) >= IFNAMSIZ)
546 goto err_out;
547 }
548
549 a_o = tc_lookup_action_n(act_name);
550 if (a_o == NULL) {
551#ifdef CONFIG_MODULES
552 rtnl_unlock();
553 request_module("act_%s", act_name);
554 rtnl_lock();
555
556 a_o = tc_lookup_action_n(act_name);
557
558 /* We dropped the RTNL semaphore in order to
559 * perform the module load. So, even if we
560 * succeeded in loading the module we have to
561 * tell the caller to replay the request. We
562 * indicate this using -EAGAIN.
563 */
564 if (a_o != NULL) {
565 err = -EAGAIN;
566 goto err_mod;
567 }
568#endif
569 err = -ENOENT;
570 goto err_out;
571 }
572
573 /* backward compatibility for policer */
574 if (name == NULL)
575 err = a_o->init(net, tb[TCA_ACT_OPTIONS], est, &a, ovr, bind);
576 else
577 err = a_o->init(net, nla, est, &a, ovr, bind);
578 if (err < 0)
579 goto err_mod;
580
581 /* module count goes up only when brand new policy is created
582 * if it exists and is only bound to in a_o->init() then
583 * ACT_P_CREATED is not returned (a zero is).
584 */
585 if (err != ACT_P_CREATED)
586 module_put(a_o->owner);
587
588 return a;
589
590err_mod:
591 module_put(a_o->owner);
592err_out:
593 return ERR_PTR(err);
594}
595
596static void cleanup_a(struct list_head *actions, int ovr)
597{
598 struct tc_action *a;
599
600 if (!ovr)
601 return;
602
603 list_for_each_entry(a, actions, list)
604 a->tcfa_refcnt--;
605}
606
607int tcf_action_init(struct net *net, struct nlattr *nla, struct nlattr *est,
608 char *name, int ovr, int bind, struct list_head *actions)
609{
610 struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
611 struct tc_action *act;
612 int err;
613 int i;
614
615 err = nla_parse_nested(tb, TCA_ACT_MAX_PRIO, nla, NULL);
616 if (err < 0)
617 return err;
618
619 for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
620 act = tcf_action_init_1(net, tb[i], est, name, ovr, bind);
621 if (IS_ERR(act)) {
622 err = PTR_ERR(act);
623 goto err;
624 }
625 act->order = i;
626 if (ovr)
627 act->tcfa_refcnt++;
628 list_add_tail(&act->list, actions);
629 }
630
631 /* Remove the temp refcnt which was necessary to protect against
632 * destroying an existing action which was being replaced
633 */
634 cleanup_a(actions, ovr);
635 return 0;
636
637err:
638 tcf_action_destroy(actions, bind);
639 return err;
640}
641
642int tcf_action_copy_stats(struct sk_buff *skb, struct tc_action *p,
643 int compat_mode)
644{
645 int err = 0;
646 struct gnet_dump d;
647
648 if (p == NULL)
649 goto errout;
650
651 /* compat_mode being true specifies a call that is supposed
652 * to add additional backward compatibility statistic TLVs.
653 */
654 if (compat_mode) {
655 if (p->type == TCA_OLD_COMPAT)
656 err = gnet_stats_start_copy_compat(skb, 0,
657 TCA_STATS,
658 TCA_XSTATS,
659 &p->tcfa_lock, &d,
660 TCA_PAD);
661 else
662 return 0;
663 } else
664 err = gnet_stats_start_copy(skb, TCA_ACT_STATS,
665 &p->tcfa_lock, &d, TCA_ACT_PAD);
666
667 if (err < 0)
668 goto errout;
669
670 if (gnet_stats_copy_basic(NULL, &d, p->cpu_bstats, &p->tcfa_bstats) < 0 ||
671 gnet_stats_copy_rate_est(&d, &p->tcfa_rate_est) < 0 ||
672 gnet_stats_copy_queue(&d, p->cpu_qstats,
673 &p->tcfa_qstats,
674 p->tcfa_qstats.qlen) < 0)
675 goto errout;
676
677 if (gnet_stats_finish_copy(&d) < 0)
678 goto errout;
679
680 return 0;
681
682errout:
683 return -1;
684}
685
686static int tca_get_fill(struct sk_buff *skb, struct list_head *actions,
687 u32 portid, u32 seq, u16 flags, int event, int bind,
688 int ref)
689{
690 struct tcamsg *t;
691 struct nlmsghdr *nlh;
692 unsigned char *b = skb_tail_pointer(skb);
693 struct nlattr *nest;
694
695 nlh = nlmsg_put(skb, portid, seq, event, sizeof(*t), flags);
696 if (!nlh)
697 goto out_nlmsg_trim;
698 t = nlmsg_data(nlh);
699 t->tca_family = AF_UNSPEC;
700 t->tca__pad1 = 0;
701 t->tca__pad2 = 0;
702
703 nest = nla_nest_start(skb, TCA_ACT_TAB);
704 if (nest == NULL)
705 goto out_nlmsg_trim;
706
707 if (tcf_action_dump(skb, actions, bind, ref) < 0)
708 goto out_nlmsg_trim;
709
710 nla_nest_end(skb, nest);
711
712 nlh->nlmsg_len = skb_tail_pointer(skb) - b;
713 return skb->len;
714
715out_nlmsg_trim:
716 nlmsg_trim(skb, b);
717 return -1;
718}
719
720static int
721act_get_notify(struct net *net, u32 portid, struct nlmsghdr *n,
722 struct list_head *actions, int event)
723{
724 struct sk_buff *skb;
725
726 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
727 if (!skb)
728 return -ENOBUFS;
729 if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, 0, event,
730 0, 0) <= 0) {
731 kfree_skb(skb);
732 return -EINVAL;
733 }
734
735 return rtnl_unicast(skb, net, portid);
736}
737
738static struct tc_action *tcf_action_get_1(struct net *net, struct nlattr *nla,
739 struct nlmsghdr *n, u32 portid)
740{
741 struct nlattr *tb[TCA_ACT_MAX + 1];
742 const struct tc_action_ops *ops;
743 struct tc_action *a;
744 int index;
745 int err;
746
747 err = nla_parse_nested(tb, TCA_ACT_MAX, nla, NULL);
748 if (err < 0)
749 goto err_out;
750
751 err = -EINVAL;
752 if (tb[TCA_ACT_INDEX] == NULL ||
753 nla_len(tb[TCA_ACT_INDEX]) < sizeof(index))
754 goto err_out;
755 index = nla_get_u32(tb[TCA_ACT_INDEX]);
756
757 err = -EINVAL;
758 ops = tc_lookup_action(tb[TCA_ACT_KIND]);
759 if (!ops) /* could happen in batch of actions */
760 goto err_out;
761 err = -ENOENT;
762 if (ops->lookup(net, &a, index) == 0)
763 goto err_mod;
764
765 module_put(ops->owner);
766 return a;
767
768err_mod:
769 module_put(ops->owner);
770err_out:
771 return ERR_PTR(err);
772}
773
774static int tca_action_flush(struct net *net, struct nlattr *nla,
775 struct nlmsghdr *n, u32 portid)
776{
777 struct sk_buff *skb;
778 unsigned char *b;
779 struct nlmsghdr *nlh;
780 struct tcamsg *t;
781 struct netlink_callback dcb;
782 struct nlattr *nest;
783 struct nlattr *tb[TCA_ACT_MAX + 1];
784 const struct tc_action_ops *ops;
785 struct nlattr *kind;
786 int err = -ENOMEM;
787
788 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
789 if (!skb) {
790 pr_debug("tca_action_flush: failed skb alloc\n");
791 return err;
792 }
793
794 b = skb_tail_pointer(skb);
795
796 err = nla_parse_nested(tb, TCA_ACT_MAX, nla, NULL);
797 if (err < 0)
798 goto err_out;
799
800 err = -EINVAL;
801 kind = tb[TCA_ACT_KIND];
802 ops = tc_lookup_action(kind);
803 if (!ops) /*some idjot trying to flush unknown action */
804 goto err_out;
805
806 nlh = nlmsg_put(skb, portid, n->nlmsg_seq, RTM_DELACTION,
807 sizeof(*t), 0);
808 if (!nlh)
809 goto out_module_put;
810 t = nlmsg_data(nlh);
811 t->tca_family = AF_UNSPEC;
812 t->tca__pad1 = 0;
813 t->tca__pad2 = 0;
814
815 nest = nla_nest_start(skb, TCA_ACT_TAB);
816 if (nest == NULL)
817 goto out_module_put;
818
819 err = ops->walk(net, skb, &dcb, RTM_DELACTION, ops);
820 if (err <= 0)
821 goto out_module_put;
822
823 nla_nest_end(skb, nest);
824
825 nlh->nlmsg_len = skb_tail_pointer(skb) - b;
826 nlh->nlmsg_flags |= NLM_F_ROOT;
827 module_put(ops->owner);
828 err = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
829 n->nlmsg_flags & NLM_F_ECHO);
830 if (err > 0)
831 return 0;
832
833 return err;
834
835out_module_put:
836 module_put(ops->owner);
837err_out:
838 kfree_skb(skb);
839 return err;
840}
841
842static int
843tcf_del_notify(struct net *net, struct nlmsghdr *n, struct list_head *actions,
844 u32 portid)
845{
846 int ret;
847 struct sk_buff *skb;
848
849 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
850 if (!skb)
851 return -ENOBUFS;
852
853 if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, 0, RTM_DELACTION,
854 0, 1) <= 0) {
855 kfree_skb(skb);
856 return -EINVAL;
857 }
858
859 /* now do the delete */
860 ret = tcf_action_destroy(actions, 0);
861 if (ret < 0) {
862 kfree_skb(skb);
863 return ret;
864 }
865
866 ret = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
867 n->nlmsg_flags & NLM_F_ECHO);
868 if (ret > 0)
869 return 0;
870 return ret;
871}
872
873static int
874tca_action_gd(struct net *net, struct nlattr *nla, struct nlmsghdr *n,
875 u32 portid, int event)
876{
877 int i, ret;
878 struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
879 struct tc_action *act;
880 LIST_HEAD(actions);
881
882 ret = nla_parse_nested(tb, TCA_ACT_MAX_PRIO, nla, NULL);
883 if (ret < 0)
884 return ret;
885
886 if (event == RTM_DELACTION && n->nlmsg_flags & NLM_F_ROOT) {
887 if (tb[1] != NULL)
888 return tca_action_flush(net, tb[1], n, portid);
889 else
890 return -EINVAL;
891 }
892
893 for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
894 act = tcf_action_get_1(net, tb[i], n, portid);
895 if (IS_ERR(act)) {
896 ret = PTR_ERR(act);
897 goto err;
898 }
899 act->order = i;
900 list_add_tail(&act->list, &actions);
901 }
902
903 if (event == RTM_GETACTION)
904 ret = act_get_notify(net, portid, n, &actions, event);
905 else { /* delete */
906 ret = tcf_del_notify(net, n, &actions, portid);
907 if (ret)
908 goto err;
909 return ret;
910 }
911err:
912 if (event != RTM_GETACTION)
913 tcf_action_destroy(&actions, 0);
914 return ret;
915}
916
917static int
918tcf_add_notify(struct net *net, struct nlmsghdr *n, struct list_head *actions,
919 u32 portid)
920{
921 struct sk_buff *skb;
922 int err = 0;
923
924 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
925 if (!skb)
926 return -ENOBUFS;
927
928 if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, n->nlmsg_flags,
929 RTM_NEWACTION, 0, 0) <= 0) {
930 kfree_skb(skb);
931 return -EINVAL;
932 }
933
934 err = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
935 n->nlmsg_flags & NLM_F_ECHO);
936 if (err > 0)
937 err = 0;
938 return err;
939}
940
941static int tcf_action_add(struct net *net, struct nlattr *nla,
942 struct nlmsghdr *n, u32 portid, int ovr)
943{
944 int ret = 0;
945 LIST_HEAD(actions);
946
947 ret = tcf_action_init(net, nla, NULL, NULL, ovr, 0, &actions);
948 if (ret)
949 return ret;
950
951 return tcf_add_notify(net, n, &actions, portid);
952}
953
954static int tc_ctl_action(struct sk_buff *skb, struct nlmsghdr *n)
955{
956 struct net *net = sock_net(skb->sk);
957 struct nlattr *tca[TCA_ACT_MAX + 1];
958 u32 portid = skb ? NETLINK_CB(skb).portid : 0;
959 int ret = 0, ovr = 0;
960
961 if ((n->nlmsg_type != RTM_GETACTION) &&
962 !netlink_capable(skb, CAP_NET_ADMIN))
963 return -EPERM;
964
965 ret = nlmsg_parse(n, sizeof(struct tcamsg), tca, TCA_ACT_MAX, NULL);
966 if (ret < 0)
967 return ret;
968
969 if (tca[TCA_ACT_TAB] == NULL) {
970 pr_notice("tc_ctl_action: received NO action attribs\n");
971 return -EINVAL;
972 }
973
974 /* n->nlmsg_flags & NLM_F_CREATE */
975 switch (n->nlmsg_type) {
976 case RTM_NEWACTION:
977 /* we are going to assume all other flags
978 * imply create only if it doesn't exist
979 * Note that CREATE | EXCL implies that
980 * but since we want avoid ambiguity (eg when flags
981 * is zero) then just set this
982 */
983 if (n->nlmsg_flags & NLM_F_REPLACE)
984 ovr = 1;
985replay:
986 ret = tcf_action_add(net, tca[TCA_ACT_TAB], n, portid, ovr);
987 if (ret == -EAGAIN)
988 goto replay;
989 break;
990 case RTM_DELACTION:
991 ret = tca_action_gd(net, tca[TCA_ACT_TAB], n,
992 portid, RTM_DELACTION);
993 break;
994 case RTM_GETACTION:
995 ret = tca_action_gd(net, tca[TCA_ACT_TAB], n,
996 portid, RTM_GETACTION);
997 break;
998 default:
999 BUG();
1000 }
1001
1002 return ret;
1003}
1004
1005static struct nlattr *find_dump_kind(const struct nlmsghdr *n)
1006{
1007 struct nlattr *tb1, *tb2[TCA_ACT_MAX + 1];
1008 struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
1009 struct nlattr *nla[TCAA_MAX + 1];
1010 struct nlattr *kind;
1011
1012 if (nlmsg_parse(n, sizeof(struct tcamsg), nla, TCAA_MAX, NULL) < 0)
1013 return NULL;
1014 tb1 = nla[TCA_ACT_TAB];
1015 if (tb1 == NULL)
1016 return NULL;
1017
1018 if (nla_parse(tb, TCA_ACT_MAX_PRIO, nla_data(tb1),
1019 NLMSG_ALIGN(nla_len(tb1)), NULL) < 0)
1020 return NULL;
1021
1022 if (tb[1] == NULL)
1023 return NULL;
1024 if (nla_parse_nested(tb2, TCA_ACT_MAX, tb[1], NULL) < 0)
1025 return NULL;
1026 kind = tb2[TCA_ACT_KIND];
1027
1028 return kind;
1029}
1030
1031static int tc_dump_action(struct sk_buff *skb, struct netlink_callback *cb)
1032{
1033 struct net *net = sock_net(skb->sk);
1034 struct nlmsghdr *nlh;
1035 unsigned char *b = skb_tail_pointer(skb);
1036 struct nlattr *nest;
1037 struct tc_action_ops *a_o;
1038 int ret = 0;
1039 struct tcamsg *t = (struct tcamsg *) nlmsg_data(cb->nlh);
1040 struct nlattr *kind = find_dump_kind(cb->nlh);
1041
1042 if (kind == NULL) {
1043 pr_info("tc_dump_action: action bad kind\n");
1044 return 0;
1045 }
1046
1047 a_o = tc_lookup_action(kind);
1048 if (a_o == NULL)
1049 return 0;
1050
1051 nlh = nlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
1052 cb->nlh->nlmsg_type, sizeof(*t), 0);
1053 if (!nlh)
1054 goto out_module_put;
1055 t = nlmsg_data(nlh);
1056 t->tca_family = AF_UNSPEC;
1057 t->tca__pad1 = 0;
1058 t->tca__pad2 = 0;
1059
1060 nest = nla_nest_start(skb, TCA_ACT_TAB);
1061 if (nest == NULL)
1062 goto out_module_put;
1063
1064 ret = a_o->walk(net, skb, cb, RTM_GETACTION, a_o);
1065 if (ret < 0)
1066 goto out_module_put;
1067
1068 if (ret > 0) {
1069 nla_nest_end(skb, nest);
1070 ret = skb->len;
1071 } else
1072 nlmsg_trim(skb, b);
1073
1074 nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1075 if (NETLINK_CB(cb->skb).portid && ret)
1076 nlh->nlmsg_flags |= NLM_F_MULTI;
1077 module_put(a_o->owner);
1078 return skb->len;
1079
1080out_module_put:
1081 module_put(a_o->owner);
1082 nlmsg_trim(skb, b);
1083 return skb->len;
1084}
1085
1086static int __init tc_action_init(void)
1087{
1088 rtnl_register(PF_UNSPEC, RTM_NEWACTION, tc_ctl_action, NULL, NULL);
1089 rtnl_register(PF_UNSPEC, RTM_DELACTION, tc_ctl_action, NULL, NULL);
1090 rtnl_register(PF_UNSPEC, RTM_GETACTION, tc_ctl_action, tc_dump_action,
1091 NULL);
1092
1093 return 0;
1094}
1095
1096subsys_initcall(tc_action_init);