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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 <net/net_namespace.h>
24#include <net/sock.h>
25#include <net/sch_generic.h>
26#include <net/act_api.h>
27#include <net/netlink.h>
28
29void tcf_hash_destroy(struct tcf_common *p, struct tcf_hashinfo *hinfo)
30{
31 unsigned int h = tcf_hash(p->tcfc_index, hinfo->hmask);
32 struct tcf_common **p1p;
33
34 for (p1p = &hinfo->htab[h]; *p1p; p1p = &(*p1p)->tcfc_next) {
35 if (*p1p == p) {
36 write_lock_bh(hinfo->lock);
37 *p1p = p->tcfc_next;
38 write_unlock_bh(hinfo->lock);
39 gen_kill_estimator(&p->tcfc_bstats,
40 &p->tcfc_rate_est);
41 /*
42 * gen_estimator est_timer() might access p->tcfc_lock
43 * or bstats, wait a RCU grace period before freeing p
44 */
45 kfree_rcu(p, tcfc_rcu);
46 return;
47 }
48 }
49 WARN_ON(1);
50}
51EXPORT_SYMBOL(tcf_hash_destroy);
52
53int tcf_hash_release(struct tcf_common *p, int bind,
54 struct tcf_hashinfo *hinfo)
55{
56 int ret = 0;
57
58 if (p) {
59 if (bind)
60 p->tcfc_bindcnt--;
61
62 p->tcfc_refcnt--;
63 if (p->tcfc_bindcnt <= 0 && p->tcfc_refcnt <= 0) {
64 tcf_hash_destroy(p, hinfo);
65 ret = 1;
66 }
67 }
68 return ret;
69}
70EXPORT_SYMBOL(tcf_hash_release);
71
72static int tcf_dump_walker(struct sk_buff *skb, struct netlink_callback *cb,
73 struct tc_action *a, struct tcf_hashinfo *hinfo)
74{
75 struct tcf_common *p;
76 int err = 0, index = -1, i = 0, s_i = 0, n_i = 0;
77 struct nlattr *nest;
78
79 read_lock_bh(hinfo->lock);
80
81 s_i = cb->args[0];
82
83 for (i = 0; i < (hinfo->hmask + 1); i++) {
84 p = hinfo->htab[tcf_hash(i, hinfo->hmask)];
85
86 for (; p; p = p->tcfc_next) {
87 index++;
88 if (index < s_i)
89 continue;
90 a->priv = p;
91 a->order = n_i;
92
93 nest = nla_nest_start(skb, a->order);
94 if (nest == NULL)
95 goto nla_put_failure;
96 err = tcf_action_dump_1(skb, a, 0, 0);
97 if (err < 0) {
98 index--;
99 nlmsg_trim(skb, nest);
100 goto done;
101 }
102 nla_nest_end(skb, nest);
103 n_i++;
104 if (n_i >= TCA_ACT_MAX_PRIO)
105 goto done;
106 }
107 }
108done:
109 read_unlock_bh(hinfo->lock);
110 if (n_i)
111 cb->args[0] += n_i;
112 return n_i;
113
114nla_put_failure:
115 nla_nest_cancel(skb, nest);
116 goto done;
117}
118
119static int tcf_del_walker(struct sk_buff *skb, struct tc_action *a,
120 struct tcf_hashinfo *hinfo)
121{
122 struct tcf_common *p, *s_p;
123 struct nlattr *nest;
124 int i = 0, n_i = 0;
125
126 nest = nla_nest_start(skb, a->order);
127 if (nest == NULL)
128 goto nla_put_failure;
129 NLA_PUT_STRING(skb, TCA_KIND, a->ops->kind);
130 for (i = 0; i < (hinfo->hmask + 1); i++) {
131 p = hinfo->htab[tcf_hash(i, hinfo->hmask)];
132
133 while (p != NULL) {
134 s_p = p->tcfc_next;
135 if (ACT_P_DELETED == tcf_hash_release(p, 0, hinfo))
136 module_put(a->ops->owner);
137 n_i++;
138 p = s_p;
139 }
140 }
141 NLA_PUT_U32(skb, TCA_FCNT, n_i);
142 nla_nest_end(skb, nest);
143
144 return n_i;
145nla_put_failure:
146 nla_nest_cancel(skb, nest);
147 return -EINVAL;
148}
149
150int tcf_generic_walker(struct sk_buff *skb, struct netlink_callback *cb,
151 int type, struct tc_action *a)
152{
153 struct tcf_hashinfo *hinfo = a->ops->hinfo;
154
155 if (type == RTM_DELACTION) {
156 return tcf_del_walker(skb, a, hinfo);
157 } else if (type == RTM_GETACTION) {
158 return tcf_dump_walker(skb, cb, a, hinfo);
159 } else {
160 WARN(1, "tcf_generic_walker: unknown action %d\n", type);
161 return -EINVAL;
162 }
163}
164EXPORT_SYMBOL(tcf_generic_walker);
165
166struct tcf_common *tcf_hash_lookup(u32 index, struct tcf_hashinfo *hinfo)
167{
168 struct tcf_common *p;
169
170 read_lock_bh(hinfo->lock);
171 for (p = hinfo->htab[tcf_hash(index, hinfo->hmask)]; p;
172 p = p->tcfc_next) {
173 if (p->tcfc_index == index)
174 break;
175 }
176 read_unlock_bh(hinfo->lock);
177
178 return p;
179}
180EXPORT_SYMBOL(tcf_hash_lookup);
181
182u32 tcf_hash_new_index(u32 *idx_gen, struct tcf_hashinfo *hinfo)
183{
184 u32 val = *idx_gen;
185
186 do {
187 if (++val == 0)
188 val = 1;
189 } while (tcf_hash_lookup(val, hinfo));
190
191 return (*idx_gen = val);
192}
193EXPORT_SYMBOL(tcf_hash_new_index);
194
195int tcf_hash_search(struct tc_action *a, u32 index)
196{
197 struct tcf_hashinfo *hinfo = a->ops->hinfo;
198 struct tcf_common *p = tcf_hash_lookup(index, hinfo);
199
200 if (p) {
201 a->priv = p;
202 return 1;
203 }
204 return 0;
205}
206EXPORT_SYMBOL(tcf_hash_search);
207
208struct tcf_common *tcf_hash_check(u32 index, struct tc_action *a, int bind,
209 struct tcf_hashinfo *hinfo)
210{
211 struct tcf_common *p = NULL;
212 if (index && (p = tcf_hash_lookup(index, hinfo)) != NULL) {
213 if (bind)
214 p->tcfc_bindcnt++;
215 p->tcfc_refcnt++;
216 a->priv = p;
217 }
218 return p;
219}
220EXPORT_SYMBOL(tcf_hash_check);
221
222struct tcf_common *tcf_hash_create(u32 index, struct nlattr *est,
223 struct tc_action *a, int size, int bind,
224 u32 *idx_gen, struct tcf_hashinfo *hinfo)
225{
226 struct tcf_common *p = kzalloc(size, GFP_KERNEL);
227
228 if (unlikely(!p))
229 return ERR_PTR(-ENOMEM);
230 p->tcfc_refcnt = 1;
231 if (bind)
232 p->tcfc_bindcnt = 1;
233
234 spin_lock_init(&p->tcfc_lock);
235 p->tcfc_index = index ? index : tcf_hash_new_index(idx_gen, hinfo);
236 p->tcfc_tm.install = jiffies;
237 p->tcfc_tm.lastuse = jiffies;
238 if (est) {
239 int err = gen_new_estimator(&p->tcfc_bstats, &p->tcfc_rate_est,
240 &p->tcfc_lock, est);
241 if (err) {
242 kfree(p);
243 return ERR_PTR(err);
244 }
245 }
246
247 a->priv = (void *) p;
248 return p;
249}
250EXPORT_SYMBOL(tcf_hash_create);
251
252void tcf_hash_insert(struct tcf_common *p, struct tcf_hashinfo *hinfo)
253{
254 unsigned int h = tcf_hash(p->tcfc_index, hinfo->hmask);
255
256 write_lock_bh(hinfo->lock);
257 p->tcfc_next = hinfo->htab[h];
258 hinfo->htab[h] = p;
259 write_unlock_bh(hinfo->lock);
260}
261EXPORT_SYMBOL(tcf_hash_insert);
262
263static struct tc_action_ops *act_base = NULL;
264static DEFINE_RWLOCK(act_mod_lock);
265
266int tcf_register_action(struct tc_action_ops *act)
267{
268 struct tc_action_ops *a, **ap;
269
270 write_lock(&act_mod_lock);
271 for (ap = &act_base; (a = *ap) != NULL; ap = &a->next) {
272 if (act->type == a->type || (strcmp(act->kind, a->kind) == 0)) {
273 write_unlock(&act_mod_lock);
274 return -EEXIST;
275 }
276 }
277 act->next = NULL;
278 *ap = act;
279 write_unlock(&act_mod_lock);
280 return 0;
281}
282EXPORT_SYMBOL(tcf_register_action);
283
284int tcf_unregister_action(struct tc_action_ops *act)
285{
286 struct tc_action_ops *a, **ap;
287 int err = -ENOENT;
288
289 write_lock(&act_mod_lock);
290 for (ap = &act_base; (a = *ap) != NULL; ap = &a->next)
291 if (a == act)
292 break;
293 if (a) {
294 *ap = a->next;
295 a->next = NULL;
296 err = 0;
297 }
298 write_unlock(&act_mod_lock);
299 return err;
300}
301EXPORT_SYMBOL(tcf_unregister_action);
302
303/* lookup by name */
304static struct tc_action_ops *tc_lookup_action_n(char *kind)
305{
306 struct tc_action_ops *a = NULL;
307
308 if (kind) {
309 read_lock(&act_mod_lock);
310 for (a = act_base; a; a = a->next) {
311 if (strcmp(kind, a->kind) == 0) {
312 if (!try_module_get(a->owner)) {
313 read_unlock(&act_mod_lock);
314 return NULL;
315 }
316 break;
317 }
318 }
319 read_unlock(&act_mod_lock);
320 }
321 return a;
322}
323
324/* lookup by nlattr */
325static struct tc_action_ops *tc_lookup_action(struct nlattr *kind)
326{
327 struct tc_action_ops *a = NULL;
328
329 if (kind) {
330 read_lock(&act_mod_lock);
331 for (a = act_base; a; a = a->next) {
332 if (nla_strcmp(kind, a->kind) == 0) {
333 if (!try_module_get(a->owner)) {
334 read_unlock(&act_mod_lock);
335 return NULL;
336 }
337 break;
338 }
339 }
340 read_unlock(&act_mod_lock);
341 }
342 return a;
343}
344
345#if 0
346/* lookup by id */
347static struct tc_action_ops *tc_lookup_action_id(u32 type)
348{
349 struct tc_action_ops *a = NULL;
350
351 if (type) {
352 read_lock(&act_mod_lock);
353 for (a = act_base; a; a = a->next) {
354 if (a->type == type) {
355 if (!try_module_get(a->owner)) {
356 read_unlock(&act_mod_lock);
357 return NULL;
358 }
359 break;
360 }
361 }
362 read_unlock(&act_mod_lock);
363 }
364 return a;
365}
366#endif
367
368int tcf_action_exec(struct sk_buff *skb, const struct tc_action *act,
369 struct tcf_result *res)
370{
371 const struct tc_action *a;
372 int ret = -1;
373
374 if (skb->tc_verd & TC_NCLS) {
375 skb->tc_verd = CLR_TC_NCLS(skb->tc_verd);
376 ret = TC_ACT_OK;
377 goto exec_done;
378 }
379 while ((a = act) != NULL) {
380repeat:
381 if (a->ops && a->ops->act) {
382 ret = a->ops->act(skb, a, res);
383 if (TC_MUNGED & skb->tc_verd) {
384 /* copied already, allow trampling */
385 skb->tc_verd = SET_TC_OK2MUNGE(skb->tc_verd);
386 skb->tc_verd = CLR_TC_MUNGED(skb->tc_verd);
387 }
388 if (ret == TC_ACT_REPEAT)
389 goto repeat; /* we need a ttl - JHS */
390 if (ret != TC_ACT_PIPE)
391 goto exec_done;
392 }
393 act = a->next;
394 }
395exec_done:
396 return ret;
397}
398EXPORT_SYMBOL(tcf_action_exec);
399
400void tcf_action_destroy(struct tc_action *act, int bind)
401{
402 struct tc_action *a;
403
404 for (a = act; a; a = act) {
405 if (a->ops && a->ops->cleanup) {
406 if (a->ops->cleanup(a, bind) == ACT_P_DELETED)
407 module_put(a->ops->owner);
408 act = act->next;
409 kfree(a);
410 } else {
411 /*FIXME: Remove later - catch insertion bugs*/
412 WARN(1, "tcf_action_destroy: BUG? destroying NULL ops\n");
413 act = act->next;
414 kfree(a);
415 }
416 }
417}
418
419int
420tcf_action_dump_old(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
421{
422 int err = -EINVAL;
423
424 if (a->ops == NULL || a->ops->dump == NULL)
425 return err;
426 return a->ops->dump(skb, a, bind, ref);
427}
428
429int
430tcf_action_dump_1(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
431{
432 int err = -EINVAL;
433 unsigned char *b = skb_tail_pointer(skb);
434 struct nlattr *nest;
435
436 if (a->ops == NULL || a->ops->dump == NULL)
437 return err;
438
439 NLA_PUT_STRING(skb, TCA_KIND, a->ops->kind);
440 if (tcf_action_copy_stats(skb, a, 0))
441 goto nla_put_failure;
442 nest = nla_nest_start(skb, TCA_OPTIONS);
443 if (nest == NULL)
444 goto nla_put_failure;
445 err = tcf_action_dump_old(skb, a, bind, ref);
446 if (err > 0) {
447 nla_nest_end(skb, nest);
448 return err;
449 }
450
451nla_put_failure:
452 nlmsg_trim(skb, b);
453 return -1;
454}
455EXPORT_SYMBOL(tcf_action_dump_1);
456
457int
458tcf_action_dump(struct sk_buff *skb, struct tc_action *act, int bind, int ref)
459{
460 struct tc_action *a;
461 int err = -EINVAL;
462 struct nlattr *nest;
463
464 while ((a = act) != NULL) {
465 act = a->next;
466 nest = nla_nest_start(skb, a->order);
467 if (nest == NULL)
468 goto nla_put_failure;
469 err = tcf_action_dump_1(skb, a, bind, ref);
470 if (err < 0)
471 goto errout;
472 nla_nest_end(skb, nest);
473 }
474
475 return 0;
476
477nla_put_failure:
478 err = -EINVAL;
479errout:
480 nla_nest_cancel(skb, nest);
481 return err;
482}
483
484struct tc_action *tcf_action_init_1(struct nlattr *nla, struct nlattr *est,
485 char *name, int ovr, int bind)
486{
487 struct tc_action *a;
488 struct tc_action_ops *a_o;
489 char act_name[IFNAMSIZ];
490 struct nlattr *tb[TCA_ACT_MAX + 1];
491 struct nlattr *kind;
492 int err;
493
494 if (name == NULL) {
495 err = nla_parse_nested(tb, TCA_ACT_MAX, nla, NULL);
496 if (err < 0)
497 goto err_out;
498 err = -EINVAL;
499 kind = tb[TCA_ACT_KIND];
500 if (kind == NULL)
501 goto err_out;
502 if (nla_strlcpy(act_name, kind, IFNAMSIZ) >= IFNAMSIZ)
503 goto err_out;
504 } else {
505 err = -EINVAL;
506 if (strlcpy(act_name, name, IFNAMSIZ) >= IFNAMSIZ)
507 goto err_out;
508 }
509
510 a_o = tc_lookup_action_n(act_name);
511 if (a_o == NULL) {
512#ifdef CONFIG_MODULES
513 rtnl_unlock();
514 request_module("act_%s", act_name);
515 rtnl_lock();
516
517 a_o = tc_lookup_action_n(act_name);
518
519 /* We dropped the RTNL semaphore in order to
520 * perform the module load. So, even if we
521 * succeeded in loading the module we have to
522 * tell the caller to replay the request. We
523 * indicate this using -EAGAIN.
524 */
525 if (a_o != NULL) {
526 err = -EAGAIN;
527 goto err_mod;
528 }
529#endif
530 err = -ENOENT;
531 goto err_out;
532 }
533
534 err = -ENOMEM;
535 a = kzalloc(sizeof(*a), GFP_KERNEL);
536 if (a == NULL)
537 goto err_mod;
538
539 /* backward compatibility for policer */
540 if (name == NULL)
541 err = a_o->init(tb[TCA_ACT_OPTIONS], est, a, ovr, bind);
542 else
543 err = a_o->init(nla, est, a, ovr, bind);
544 if (err < 0)
545 goto err_free;
546
547 /* module count goes up only when brand new policy is created
548 * if it exists and is only bound to in a_o->init() then
549 * ACT_P_CREATED is not returned (a zero is).
550 */
551 if (err != ACT_P_CREATED)
552 module_put(a_o->owner);
553 a->ops = a_o;
554
555 return a;
556
557err_free:
558 kfree(a);
559err_mod:
560 module_put(a_o->owner);
561err_out:
562 return ERR_PTR(err);
563}
564
565struct tc_action *tcf_action_init(struct nlattr *nla, struct nlattr *est,
566 char *name, int ovr, int bind)
567{
568 struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
569 struct tc_action *head = NULL, *act, *act_prev = NULL;
570 int err;
571 int i;
572
573 err = nla_parse_nested(tb, TCA_ACT_MAX_PRIO, nla, NULL);
574 if (err < 0)
575 return ERR_PTR(err);
576
577 for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
578 act = tcf_action_init_1(tb[i], est, name, ovr, bind);
579 if (IS_ERR(act))
580 goto err;
581 act->order = i;
582
583 if (head == NULL)
584 head = act;
585 else
586 act_prev->next = act;
587 act_prev = act;
588 }
589 return head;
590
591err:
592 if (head != NULL)
593 tcf_action_destroy(head, bind);
594 return act;
595}
596
597int tcf_action_copy_stats(struct sk_buff *skb, struct tc_action *a,
598 int compat_mode)
599{
600 int err = 0;
601 struct gnet_dump d;
602 struct tcf_act_hdr *h = a->priv;
603
604 if (h == NULL)
605 goto errout;
606
607 /* compat_mode being true specifies a call that is supposed
608 * to add additional backward compatibility statistic TLVs.
609 */
610 if (compat_mode) {
611 if (a->type == TCA_OLD_COMPAT)
612 err = gnet_stats_start_copy_compat(skb, 0,
613 TCA_STATS, TCA_XSTATS, &h->tcf_lock, &d);
614 else
615 return 0;
616 } else
617 err = gnet_stats_start_copy(skb, TCA_ACT_STATS,
618 &h->tcf_lock, &d);
619
620 if (err < 0)
621 goto errout;
622
623 if (a->ops != NULL && a->ops->get_stats != NULL)
624 if (a->ops->get_stats(skb, a) < 0)
625 goto errout;
626
627 if (gnet_stats_copy_basic(&d, &h->tcf_bstats) < 0 ||
628 gnet_stats_copy_rate_est(&d, &h->tcf_bstats,
629 &h->tcf_rate_est) < 0 ||
630 gnet_stats_copy_queue(&d, &h->tcf_qstats) < 0)
631 goto errout;
632
633 if (gnet_stats_finish_copy(&d) < 0)
634 goto errout;
635
636 return 0;
637
638errout:
639 return -1;
640}
641
642static int
643tca_get_fill(struct sk_buff *skb, struct tc_action *a, u32 pid, u32 seq,
644 u16 flags, int event, int bind, int ref)
645{
646 struct tcamsg *t;
647 struct nlmsghdr *nlh;
648 unsigned char *b = skb_tail_pointer(skb);
649 struct nlattr *nest;
650
651 nlh = NLMSG_NEW(skb, pid, seq, event, sizeof(*t), flags);
652
653 t = NLMSG_DATA(nlh);
654 t->tca_family = AF_UNSPEC;
655 t->tca__pad1 = 0;
656 t->tca__pad2 = 0;
657
658 nest = nla_nest_start(skb, TCA_ACT_TAB);
659 if (nest == NULL)
660 goto nla_put_failure;
661
662 if (tcf_action_dump(skb, a, bind, ref) < 0)
663 goto nla_put_failure;
664
665 nla_nest_end(skb, nest);
666
667 nlh->nlmsg_len = skb_tail_pointer(skb) - b;
668 return skb->len;
669
670nla_put_failure:
671nlmsg_failure:
672 nlmsg_trim(skb, b);
673 return -1;
674}
675
676static int
677act_get_notify(struct net *net, u32 pid, struct nlmsghdr *n,
678 struct tc_action *a, int event)
679{
680 struct sk_buff *skb;
681
682 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
683 if (!skb)
684 return -ENOBUFS;
685 if (tca_get_fill(skb, a, pid, n->nlmsg_seq, 0, event, 0, 0) <= 0) {
686 kfree_skb(skb);
687 return -EINVAL;
688 }
689
690 return rtnl_unicast(skb, net, pid);
691}
692
693static struct tc_action *
694tcf_action_get_1(struct nlattr *nla, struct nlmsghdr *n, u32 pid)
695{
696 struct nlattr *tb[TCA_ACT_MAX + 1];
697 struct tc_action *a;
698 int index;
699 int err;
700
701 err = nla_parse_nested(tb, TCA_ACT_MAX, nla, NULL);
702 if (err < 0)
703 goto err_out;
704
705 err = -EINVAL;
706 if (tb[TCA_ACT_INDEX] == NULL ||
707 nla_len(tb[TCA_ACT_INDEX]) < sizeof(index))
708 goto err_out;
709 index = nla_get_u32(tb[TCA_ACT_INDEX]);
710
711 err = -ENOMEM;
712 a = kzalloc(sizeof(struct tc_action), GFP_KERNEL);
713 if (a == NULL)
714 goto err_out;
715
716 err = -EINVAL;
717 a->ops = tc_lookup_action(tb[TCA_ACT_KIND]);
718 if (a->ops == NULL)
719 goto err_free;
720 if (a->ops->lookup == NULL)
721 goto err_mod;
722 err = -ENOENT;
723 if (a->ops->lookup(a, index) == 0)
724 goto err_mod;
725
726 module_put(a->ops->owner);
727 return a;
728
729err_mod:
730 module_put(a->ops->owner);
731err_free:
732 kfree(a);
733err_out:
734 return ERR_PTR(err);
735}
736
737static void cleanup_a(struct tc_action *act)
738{
739 struct tc_action *a;
740
741 for (a = act; a; a = act) {
742 act = a->next;
743 kfree(a);
744 }
745}
746
747static struct tc_action *create_a(int i)
748{
749 struct tc_action *act;
750
751 act = kzalloc(sizeof(*act), GFP_KERNEL);
752 if (act == NULL) {
753 pr_debug("create_a: failed to alloc!\n");
754 return NULL;
755 }
756 act->order = i;
757 return act;
758}
759
760static int tca_action_flush(struct net *net, struct nlattr *nla,
761 struct nlmsghdr *n, u32 pid)
762{
763 struct sk_buff *skb;
764 unsigned char *b;
765 struct nlmsghdr *nlh;
766 struct tcamsg *t;
767 struct netlink_callback dcb;
768 struct nlattr *nest;
769 struct nlattr *tb[TCA_ACT_MAX + 1];
770 struct nlattr *kind;
771 struct tc_action *a = create_a(0);
772 int err = -ENOMEM;
773
774 if (a == NULL) {
775 pr_debug("tca_action_flush: couldnt create tc_action\n");
776 return err;
777 }
778
779 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
780 if (!skb) {
781 pr_debug("tca_action_flush: failed skb alloc\n");
782 kfree(a);
783 return err;
784 }
785
786 b = skb_tail_pointer(skb);
787
788 err = nla_parse_nested(tb, TCA_ACT_MAX, nla, NULL);
789 if (err < 0)
790 goto err_out;
791
792 err = -EINVAL;
793 kind = tb[TCA_ACT_KIND];
794 a->ops = tc_lookup_action(kind);
795 if (a->ops == NULL)
796 goto err_out;
797
798 nlh = NLMSG_PUT(skb, pid, n->nlmsg_seq, RTM_DELACTION, sizeof(*t));
799 t = NLMSG_DATA(nlh);
800 t->tca_family = AF_UNSPEC;
801 t->tca__pad1 = 0;
802 t->tca__pad2 = 0;
803
804 nest = nla_nest_start(skb, TCA_ACT_TAB);
805 if (nest == NULL)
806 goto nla_put_failure;
807
808 err = a->ops->walk(skb, &dcb, RTM_DELACTION, a);
809 if (err < 0)
810 goto nla_put_failure;
811 if (err == 0)
812 goto noflush_out;
813
814 nla_nest_end(skb, nest);
815
816 nlh->nlmsg_len = skb_tail_pointer(skb) - b;
817 nlh->nlmsg_flags |= NLM_F_ROOT;
818 module_put(a->ops->owner);
819 kfree(a);
820 err = rtnetlink_send(skb, net, pid, RTNLGRP_TC,
821 n->nlmsg_flags & NLM_F_ECHO);
822 if (err > 0)
823 return 0;
824
825 return err;
826
827nla_put_failure:
828nlmsg_failure:
829 module_put(a->ops->owner);
830err_out:
831noflush_out:
832 kfree_skb(skb);
833 kfree(a);
834 return err;
835}
836
837static int
838tca_action_gd(struct net *net, struct nlattr *nla, struct nlmsghdr *n,
839 u32 pid, int event)
840{
841 int i, ret;
842 struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
843 struct tc_action *head = NULL, *act, *act_prev = NULL;
844
845 ret = nla_parse_nested(tb, TCA_ACT_MAX_PRIO, nla, NULL);
846 if (ret < 0)
847 return ret;
848
849 if (event == RTM_DELACTION && n->nlmsg_flags & NLM_F_ROOT) {
850 if (tb[1] != NULL)
851 return tca_action_flush(net, tb[1], n, pid);
852 else
853 return -EINVAL;
854 }
855
856 for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
857 act = tcf_action_get_1(tb[i], n, pid);
858 if (IS_ERR(act)) {
859 ret = PTR_ERR(act);
860 goto err;
861 }
862 act->order = i;
863
864 if (head == NULL)
865 head = act;
866 else
867 act_prev->next = act;
868 act_prev = act;
869 }
870
871 if (event == RTM_GETACTION)
872 ret = act_get_notify(net, pid, n, head, event);
873 else { /* delete */
874 struct sk_buff *skb;
875
876 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
877 if (!skb) {
878 ret = -ENOBUFS;
879 goto err;
880 }
881
882 if (tca_get_fill(skb, head, pid, n->nlmsg_seq, 0, event,
883 0, 1) <= 0) {
884 kfree_skb(skb);
885 ret = -EINVAL;
886 goto err;
887 }
888
889 /* now do the delete */
890 tcf_action_destroy(head, 0);
891 ret = rtnetlink_send(skb, net, pid, RTNLGRP_TC,
892 n->nlmsg_flags & NLM_F_ECHO);
893 if (ret > 0)
894 return 0;
895 return ret;
896 }
897err:
898 cleanup_a(head);
899 return ret;
900}
901
902static int tcf_add_notify(struct net *net, struct tc_action *a,
903 u32 pid, u32 seq, int event, u16 flags)
904{
905 struct tcamsg *t;
906 struct nlmsghdr *nlh;
907 struct sk_buff *skb;
908 struct nlattr *nest;
909 unsigned char *b;
910 int err = 0;
911
912 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
913 if (!skb)
914 return -ENOBUFS;
915
916 b = skb_tail_pointer(skb);
917
918 nlh = NLMSG_NEW(skb, pid, seq, event, sizeof(*t), flags);
919 t = NLMSG_DATA(nlh);
920 t->tca_family = AF_UNSPEC;
921 t->tca__pad1 = 0;
922 t->tca__pad2 = 0;
923
924 nest = nla_nest_start(skb, TCA_ACT_TAB);
925 if (nest == NULL)
926 goto nla_put_failure;
927
928 if (tcf_action_dump(skb, a, 0, 0) < 0)
929 goto nla_put_failure;
930
931 nla_nest_end(skb, nest);
932
933 nlh->nlmsg_len = skb_tail_pointer(skb) - b;
934 NETLINK_CB(skb).dst_group = RTNLGRP_TC;
935
936 err = rtnetlink_send(skb, net, pid, RTNLGRP_TC, flags & NLM_F_ECHO);
937 if (err > 0)
938 err = 0;
939 return err;
940
941nla_put_failure:
942nlmsg_failure:
943 kfree_skb(skb);
944 return -1;
945}
946
947
948static int
949tcf_action_add(struct net *net, struct nlattr *nla, struct nlmsghdr *n,
950 u32 pid, int ovr)
951{
952 int ret = 0;
953 struct tc_action *act;
954 struct tc_action *a;
955 u32 seq = n->nlmsg_seq;
956
957 act = tcf_action_init(nla, NULL, NULL, ovr, 0);
958 if (act == NULL)
959 goto done;
960 if (IS_ERR(act)) {
961 ret = PTR_ERR(act);
962 goto done;
963 }
964
965 /* dump then free all the actions after update; inserted policy
966 * stays intact
967 */
968 ret = tcf_add_notify(net, act, pid, seq, RTM_NEWACTION, n->nlmsg_flags);
969 for (a = act; a; a = act) {
970 act = a->next;
971 kfree(a);
972 }
973done:
974 return ret;
975}
976
977static int tc_ctl_action(struct sk_buff *skb, struct nlmsghdr *n, void *arg)
978{
979 struct net *net = sock_net(skb->sk);
980 struct nlattr *tca[TCA_ACT_MAX + 1];
981 u32 pid = skb ? NETLINK_CB(skb).pid : 0;
982 int ret = 0, ovr = 0;
983
984 ret = nlmsg_parse(n, sizeof(struct tcamsg), tca, TCA_ACT_MAX, NULL);
985 if (ret < 0)
986 return ret;
987
988 if (tca[TCA_ACT_TAB] == NULL) {
989 pr_notice("tc_ctl_action: received NO action attribs\n");
990 return -EINVAL;
991 }
992
993 /* n->nlmsg_flags & NLM_F_CREATE */
994 switch (n->nlmsg_type) {
995 case RTM_NEWACTION:
996 /* we are going to assume all other flags
997 * imply create only if it doesn't exist
998 * Note that CREATE | EXCL implies that
999 * but since we want avoid ambiguity (eg when flags
1000 * is zero) then just set this
1001 */
1002 if (n->nlmsg_flags & NLM_F_REPLACE)
1003 ovr = 1;
1004replay:
1005 ret = tcf_action_add(net, tca[TCA_ACT_TAB], n, pid, ovr);
1006 if (ret == -EAGAIN)
1007 goto replay;
1008 break;
1009 case RTM_DELACTION:
1010 ret = tca_action_gd(net, tca[TCA_ACT_TAB], n,
1011 pid, RTM_DELACTION);
1012 break;
1013 case RTM_GETACTION:
1014 ret = tca_action_gd(net, tca[TCA_ACT_TAB], n,
1015 pid, RTM_GETACTION);
1016 break;
1017 default:
1018 BUG();
1019 }
1020
1021 return ret;
1022}
1023
1024static struct nlattr *
1025find_dump_kind(const struct nlmsghdr *n)
1026{
1027 struct nlattr *tb1, *tb2[TCA_ACT_MAX + 1];
1028 struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
1029 struct nlattr *nla[TCAA_MAX + 1];
1030 struct nlattr *kind;
1031
1032 if (nlmsg_parse(n, sizeof(struct tcamsg), nla, TCAA_MAX, NULL) < 0)
1033 return NULL;
1034 tb1 = nla[TCA_ACT_TAB];
1035 if (tb1 == NULL)
1036 return NULL;
1037
1038 if (nla_parse(tb, TCA_ACT_MAX_PRIO, nla_data(tb1),
1039 NLMSG_ALIGN(nla_len(tb1)), NULL) < 0)
1040 return NULL;
1041
1042 if (tb[1] == NULL)
1043 return NULL;
1044 if (nla_parse(tb2, TCA_ACT_MAX, nla_data(tb[1]),
1045 nla_len(tb[1]), NULL) < 0)
1046 return NULL;
1047 kind = tb2[TCA_ACT_KIND];
1048
1049 return kind;
1050}
1051
1052static int
1053tc_dump_action(struct sk_buff *skb, struct netlink_callback *cb)
1054{
1055 struct nlmsghdr *nlh;
1056 unsigned char *b = skb_tail_pointer(skb);
1057 struct nlattr *nest;
1058 struct tc_action_ops *a_o;
1059 struct tc_action a;
1060 int ret = 0;
1061 struct tcamsg *t = (struct tcamsg *) NLMSG_DATA(cb->nlh);
1062 struct nlattr *kind = find_dump_kind(cb->nlh);
1063
1064 if (kind == NULL) {
1065 pr_info("tc_dump_action: action bad kind\n");
1066 return 0;
1067 }
1068
1069 a_o = tc_lookup_action(kind);
1070 if (a_o == NULL)
1071 return 0;
1072
1073 memset(&a, 0, sizeof(struct tc_action));
1074 a.ops = a_o;
1075
1076 if (a_o->walk == NULL) {
1077 WARN(1, "tc_dump_action: %s !capable of dumping table\n",
1078 a_o->kind);
1079 goto nla_put_failure;
1080 }
1081
1082 nlh = NLMSG_PUT(skb, NETLINK_CB(cb->skb).pid, cb->nlh->nlmsg_seq,
1083 cb->nlh->nlmsg_type, sizeof(*t));
1084 t = NLMSG_DATA(nlh);
1085 t->tca_family = AF_UNSPEC;
1086 t->tca__pad1 = 0;
1087 t->tca__pad2 = 0;
1088
1089 nest = nla_nest_start(skb, TCA_ACT_TAB);
1090 if (nest == NULL)
1091 goto nla_put_failure;
1092
1093 ret = a_o->walk(skb, cb, RTM_GETACTION, &a);
1094 if (ret < 0)
1095 goto nla_put_failure;
1096
1097 if (ret > 0) {
1098 nla_nest_end(skb, nest);
1099 ret = skb->len;
1100 } else
1101 nla_nest_cancel(skb, nest);
1102
1103 nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1104 if (NETLINK_CB(cb->skb).pid && ret)
1105 nlh->nlmsg_flags |= NLM_F_MULTI;
1106 module_put(a_o->owner);
1107 return skb->len;
1108
1109nla_put_failure:
1110nlmsg_failure:
1111 module_put(a_o->owner);
1112 nlmsg_trim(skb, b);
1113 return skb->len;
1114}
1115
1116static int __init tc_action_init(void)
1117{
1118 rtnl_register(PF_UNSPEC, RTM_NEWACTION, tc_ctl_action, NULL, NULL);
1119 rtnl_register(PF_UNSPEC, RTM_DELACTION, tc_ctl_action, NULL, NULL);
1120 rtnl_register(PF_UNSPEC, RTM_GETACTION, tc_ctl_action, tc_dump_action,
1121 NULL);
1122
1123 return 0;
1124}
1125
1126subsys_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);