148a89ab789b56bdc8117035431d827a22753494
[sfrench/cifs-2.6.git] / net / sched / act_api.c
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 <linux/rhashtable.h>
25 #include <linux/list.h>
26 #include <net/net_namespace.h>
27 #include <net/sock.h>
28 #include <net/sch_generic.h>
29 #include <net/pkt_cls.h>
30 #include <net/act_api.h>
31 #include <net/netlink.h>
32
33 static int tcf_action_goto_chain_init(struct tc_action *a, struct tcf_proto *tp)
34 {
35         u32 chain_index = a->tcfa_action & TC_ACT_EXT_VAL_MASK;
36
37         if (!tp)
38                 return -EINVAL;
39         a->goto_chain = tcf_chain_get(tp->chain->block, chain_index, true);
40         if (!a->goto_chain)
41                 return -ENOMEM;
42         return 0;
43 }
44
45 static void tcf_action_goto_chain_fini(struct tc_action *a)
46 {
47         tcf_chain_put(a->goto_chain);
48 }
49
50 static void tcf_action_goto_chain_exec(const struct tc_action *a,
51                                        struct tcf_result *res)
52 {
53         const struct tcf_chain *chain = a->goto_chain;
54
55         res->goto_tp = rcu_dereference_bh(chain->filter_chain);
56 }
57
58 static void tcf_free_cookie_rcu(struct rcu_head *p)
59 {
60         struct tc_cookie *cookie = container_of(p, struct tc_cookie, rcu);
61
62         kfree(cookie->data);
63         kfree(cookie);
64 }
65
66 static void tcf_set_action_cookie(struct tc_cookie __rcu **old_cookie,
67                                   struct tc_cookie *new_cookie)
68 {
69         struct tc_cookie *old;
70
71         old = xchg((__force struct tc_cookie **)old_cookie, new_cookie);
72         if (old)
73                 call_rcu(&old->rcu, tcf_free_cookie_rcu);
74 }
75
76 /* XXX: For standalone actions, we don't need a RCU grace period either, because
77  * actions are always connected to filters and filters are already destroyed in
78  * RCU callbacks, so after a RCU grace period actions are already disconnected
79  * from filters. Readers later can not find us.
80  */
81 static void free_tcf(struct tc_action *p)
82 {
83         free_percpu(p->cpu_bstats);
84         free_percpu(p->cpu_qstats);
85
86         tcf_set_action_cookie(&p->act_cookie, NULL);
87         if (p->goto_chain)
88                 tcf_action_goto_chain_fini(p);
89
90         kfree(p);
91 }
92
93 static void tcf_action_cleanup(struct tc_action *p)
94 {
95         if (p->ops->cleanup)
96                 p->ops->cleanup(p);
97
98         gen_kill_estimator(&p->tcfa_rate_est);
99         free_tcf(p);
100 }
101
102 static int __tcf_action_put(struct tc_action *p, bool bind)
103 {
104         struct tcf_idrinfo *idrinfo = p->idrinfo;
105
106         if (refcount_dec_and_lock(&p->tcfa_refcnt, &idrinfo->lock)) {
107                 if (bind)
108                         atomic_dec(&p->tcfa_bindcnt);
109                 idr_remove(&idrinfo->action_idr, p->tcfa_index);
110                 spin_unlock(&idrinfo->lock);
111
112                 tcf_action_cleanup(p);
113                 return 1;
114         }
115
116         if (bind)
117                 atomic_dec(&p->tcfa_bindcnt);
118
119         return 0;
120 }
121
122 int __tcf_idr_release(struct tc_action *p, bool bind, bool strict)
123 {
124         int ret = 0;
125
126         /* Release with strict==1 and bind==0 is only called through act API
127          * interface (classifiers always bind). Only case when action with
128          * positive reference count and zero bind count can exist is when it was
129          * also created with act API (unbinding last classifier will destroy the
130          * action if it was created by classifier). So only case when bind count
131          * can be changed after initial check is when unbound action is
132          * destroyed by act API while classifier binds to action with same id
133          * concurrently. This result either creation of new action(same behavior
134          * as before), or reusing existing action if concurrent process
135          * increments reference count before action is deleted. Both scenarios
136          * are acceptable.
137          */
138         if (p) {
139                 if (!bind && strict && atomic_read(&p->tcfa_bindcnt) > 0)
140                         return -EPERM;
141
142                 if (__tcf_action_put(p, bind))
143                         ret = ACT_P_DELETED;
144         }
145
146         return ret;
147 }
148 EXPORT_SYMBOL(__tcf_idr_release);
149
150 static size_t tcf_action_shared_attrs_size(const struct tc_action *act)
151 {
152         struct tc_cookie *act_cookie;
153         u32 cookie_len = 0;
154
155         rcu_read_lock();
156         act_cookie = rcu_dereference(act->act_cookie);
157
158         if (act_cookie)
159                 cookie_len = nla_total_size(act_cookie->len);
160         rcu_read_unlock();
161
162         return  nla_total_size(0) /* action number nested */
163                 + nla_total_size(IFNAMSIZ) /* TCA_ACT_KIND */
164                 + cookie_len /* TCA_ACT_COOKIE */
165                 + nla_total_size(0) /* TCA_ACT_STATS nested */
166                 /* TCA_STATS_BASIC */
167                 + nla_total_size_64bit(sizeof(struct gnet_stats_basic))
168                 /* TCA_STATS_QUEUE */
169                 + nla_total_size_64bit(sizeof(struct gnet_stats_queue))
170                 + nla_total_size(0) /* TCA_OPTIONS nested */
171                 + nla_total_size(sizeof(struct tcf_t)); /* TCA_GACT_TM */
172 }
173
174 static size_t tcf_action_full_attrs_size(size_t sz)
175 {
176         return NLMSG_HDRLEN                     /* struct nlmsghdr */
177                 + sizeof(struct tcamsg)
178                 + nla_total_size(0)             /* TCA_ACT_TAB nested */
179                 + sz;
180 }
181
182 static size_t tcf_action_fill_size(const struct tc_action *act)
183 {
184         size_t sz = tcf_action_shared_attrs_size(act);
185
186         if (act->ops->get_fill_size)
187                 return act->ops->get_fill_size(act) + sz;
188         return sz;
189 }
190
191 static int tcf_dump_walker(struct tcf_idrinfo *idrinfo, struct sk_buff *skb,
192                            struct netlink_callback *cb)
193 {
194         int err = 0, index = -1, s_i = 0, n_i = 0;
195         u32 act_flags = cb->args[2];
196         unsigned long jiffy_since = cb->args[3];
197         struct nlattr *nest;
198         struct idr *idr = &idrinfo->action_idr;
199         struct tc_action *p;
200         unsigned long id = 1;
201
202         spin_lock(&idrinfo->lock);
203
204         s_i = cb->args[0];
205
206         idr_for_each_entry_ul(idr, p, id) {
207                 index++;
208                 if (index < s_i)
209                         continue;
210
211                 if (jiffy_since &&
212                     time_after(jiffy_since,
213                                (unsigned long)p->tcfa_tm.lastuse))
214                         continue;
215
216                 nest = nla_nest_start(skb, n_i);
217                 if (!nest) {
218                         index--;
219                         goto nla_put_failure;
220                 }
221                 err = tcf_action_dump_1(skb, p, 0, 0);
222                 if (err < 0) {
223                         index--;
224                         nlmsg_trim(skb, nest);
225                         goto done;
226                 }
227                 nla_nest_end(skb, nest);
228                 n_i++;
229                 if (!(act_flags & TCA_FLAG_LARGE_DUMP_ON) &&
230                     n_i >= TCA_ACT_MAX_PRIO)
231                         goto done;
232         }
233 done:
234         if (index >= 0)
235                 cb->args[0] = index + 1;
236
237         spin_unlock(&idrinfo->lock);
238         if (n_i) {
239                 if (act_flags & TCA_FLAG_LARGE_DUMP_ON)
240                         cb->args[1] = n_i;
241         }
242         return n_i;
243
244 nla_put_failure:
245         nla_nest_cancel(skb, nest);
246         goto done;
247 }
248
249 static int tcf_del_walker(struct tcf_idrinfo *idrinfo, struct sk_buff *skb,
250                           const struct tc_action_ops *ops)
251 {
252         struct nlattr *nest;
253         int n_i = 0;
254         int ret = -EINVAL;
255         struct idr *idr = &idrinfo->action_idr;
256         struct tc_action *p;
257         unsigned long id = 1;
258
259         nest = nla_nest_start(skb, 0);
260         if (nest == NULL)
261                 goto nla_put_failure;
262         if (nla_put_string(skb, TCA_KIND, ops->kind))
263                 goto nla_put_failure;
264
265         idr_for_each_entry_ul(idr, p, id) {
266                 ret = __tcf_idr_release(p, false, true);
267                 if (ret == ACT_P_DELETED) {
268                         module_put(ops->owner);
269                         n_i++;
270                 } else if (ret < 0) {
271                         goto nla_put_failure;
272                 }
273         }
274         if (nla_put_u32(skb, TCA_FCNT, n_i))
275                 goto nla_put_failure;
276         nla_nest_end(skb, nest);
277
278         return n_i;
279 nla_put_failure:
280         nla_nest_cancel(skb, nest);
281         return ret;
282 }
283
284 int tcf_generic_walker(struct tc_action_net *tn, struct sk_buff *skb,
285                        struct netlink_callback *cb, int type,
286                        const struct tc_action_ops *ops,
287                        struct netlink_ext_ack *extack)
288 {
289         struct tcf_idrinfo *idrinfo = tn->idrinfo;
290
291         if (type == RTM_DELACTION) {
292                 return tcf_del_walker(idrinfo, skb, ops);
293         } else if (type == RTM_GETACTION) {
294                 return tcf_dump_walker(idrinfo, skb, cb);
295         } else {
296                 WARN(1, "tcf_generic_walker: unknown command %d\n", type);
297                 NL_SET_ERR_MSG(extack, "tcf_generic_walker: unknown command");
298                 return -EINVAL;
299         }
300 }
301 EXPORT_SYMBOL(tcf_generic_walker);
302
303 static bool __tcf_idr_check(struct tc_action_net *tn, u32 index,
304                             struct tc_action **a, int bind)
305 {
306         struct tcf_idrinfo *idrinfo = tn->idrinfo;
307         struct tc_action *p;
308
309         spin_lock(&idrinfo->lock);
310         p = idr_find(&idrinfo->action_idr, index);
311         if (IS_ERR(p)) {
312                 p = NULL;
313         } else if (p) {
314                 refcount_inc(&p->tcfa_refcnt);
315                 if (bind)
316                         atomic_inc(&p->tcfa_bindcnt);
317         }
318         spin_unlock(&idrinfo->lock);
319
320         if (p) {
321                 *a = p;
322                 return true;
323         }
324         return false;
325 }
326
327 int tcf_idr_search(struct tc_action_net *tn, struct tc_action **a, u32 index)
328 {
329         return __tcf_idr_check(tn, index, a, 0);
330 }
331 EXPORT_SYMBOL(tcf_idr_search);
332
333 bool tcf_idr_check(struct tc_action_net *tn, u32 index, struct tc_action **a,
334                    int bind)
335 {
336         return __tcf_idr_check(tn, index, a, bind);
337 }
338 EXPORT_SYMBOL(tcf_idr_check);
339
340 int tcf_idr_delete_index(struct tc_action_net *tn, u32 index)
341 {
342         struct tcf_idrinfo *idrinfo = tn->idrinfo;
343         struct tc_action *p;
344         int ret = 0;
345
346         spin_lock(&idrinfo->lock);
347         p = idr_find(&idrinfo->action_idr, index);
348         if (!p) {
349                 spin_unlock(&idrinfo->lock);
350                 return -ENOENT;
351         }
352
353         if (!atomic_read(&p->tcfa_bindcnt)) {
354                 if (refcount_dec_and_test(&p->tcfa_refcnt)) {
355                         struct module *owner = p->ops->owner;
356
357                         WARN_ON(p != idr_remove(&idrinfo->action_idr,
358                                                 p->tcfa_index));
359                         spin_unlock(&idrinfo->lock);
360
361                         tcf_action_cleanup(p);
362                         module_put(owner);
363                         return 0;
364                 }
365                 ret = 0;
366         } else {
367                 ret = -EPERM;
368         }
369
370         spin_unlock(&idrinfo->lock);
371         return ret;
372 }
373 EXPORT_SYMBOL(tcf_idr_delete_index);
374
375 int tcf_idr_create(struct tc_action_net *tn, u32 index, struct nlattr *est,
376                    struct tc_action **a, const struct tc_action_ops *ops,
377                    int bind, bool cpustats)
378 {
379         struct tc_action *p = kzalloc(ops->size, GFP_KERNEL);
380         struct tcf_idrinfo *idrinfo = tn->idrinfo;
381         int err = -ENOMEM;
382
383         if (unlikely(!p))
384                 return -ENOMEM;
385         refcount_set(&p->tcfa_refcnt, 1);
386         if (bind)
387                 atomic_set(&p->tcfa_bindcnt, 1);
388
389         if (cpustats) {
390                 p->cpu_bstats = netdev_alloc_pcpu_stats(struct gnet_stats_basic_cpu);
391                 if (!p->cpu_bstats)
392                         goto err1;
393                 p->cpu_qstats = alloc_percpu(struct gnet_stats_queue);
394                 if (!p->cpu_qstats)
395                         goto err2;
396         }
397         spin_lock_init(&p->tcfa_lock);
398         p->tcfa_index = index;
399         p->tcfa_tm.install = jiffies;
400         p->tcfa_tm.lastuse = jiffies;
401         p->tcfa_tm.firstuse = 0;
402         if (est) {
403                 err = gen_new_estimator(&p->tcfa_bstats, p->cpu_bstats,
404                                         &p->tcfa_rate_est,
405                                         &p->tcfa_lock, NULL, est);
406                 if (err)
407                         goto err3;
408         }
409
410         p->idrinfo = idrinfo;
411         p->ops = ops;
412         INIT_LIST_HEAD(&p->list);
413         *a = p;
414         return 0;
415 err3:
416         free_percpu(p->cpu_qstats);
417 err2:
418         free_percpu(p->cpu_bstats);
419 err1:
420         kfree(p);
421         return err;
422 }
423 EXPORT_SYMBOL(tcf_idr_create);
424
425 void tcf_idr_insert(struct tc_action_net *tn, struct tc_action *a)
426 {
427         struct tcf_idrinfo *idrinfo = tn->idrinfo;
428
429         spin_lock(&idrinfo->lock);
430         /* Replace ERR_PTR(-EBUSY) allocated by tcf_idr_check_alloc */
431         WARN_ON(!IS_ERR(idr_replace(&idrinfo->action_idr, a, a->tcfa_index)));
432         spin_unlock(&idrinfo->lock);
433 }
434 EXPORT_SYMBOL(tcf_idr_insert);
435
436 /* Cleanup idr index that was allocated but not initialized. */
437
438 void tcf_idr_cleanup(struct tc_action_net *tn, u32 index)
439 {
440         struct tcf_idrinfo *idrinfo = tn->idrinfo;
441
442         spin_lock(&idrinfo->lock);
443         /* Remove ERR_PTR(-EBUSY) allocated by tcf_idr_check_alloc */
444         WARN_ON(!IS_ERR(idr_remove(&idrinfo->action_idr, index)));
445         spin_unlock(&idrinfo->lock);
446 }
447 EXPORT_SYMBOL(tcf_idr_cleanup);
448
449 /* Check if action with specified index exists. If actions is found, increments
450  * its reference and bind counters, and return 1. Otherwise insert temporary
451  * error pointer (to prevent concurrent users from inserting actions with same
452  * index) and return 0.
453  */
454
455 int tcf_idr_check_alloc(struct tc_action_net *tn, u32 *index,
456                         struct tc_action **a, int bind)
457 {
458         struct tcf_idrinfo *idrinfo = tn->idrinfo;
459         struct tc_action *p;
460         int ret;
461
462 again:
463         spin_lock(&idrinfo->lock);
464         if (*index) {
465                 p = idr_find(&idrinfo->action_idr, *index);
466                 if (IS_ERR(p)) {
467                         /* This means that another process allocated
468                          * index but did not assign the pointer yet.
469                          */
470                         spin_unlock(&idrinfo->lock);
471                         goto again;
472                 }
473
474                 if (p) {
475                         refcount_inc(&p->tcfa_refcnt);
476                         if (bind)
477                                 atomic_inc(&p->tcfa_bindcnt);
478                         *a = p;
479                         ret = 1;
480                 } else {
481                         *a = NULL;
482                         ret = idr_alloc_u32(&idrinfo->action_idr, NULL, index,
483                                             *index, GFP_ATOMIC);
484                         if (!ret)
485                                 idr_replace(&idrinfo->action_idr,
486                                             ERR_PTR(-EBUSY), *index);
487                 }
488         } else {
489                 *index = 1;
490                 *a = NULL;
491                 ret = idr_alloc_u32(&idrinfo->action_idr, NULL, index,
492                                     UINT_MAX, GFP_ATOMIC);
493                 if (!ret)
494                         idr_replace(&idrinfo->action_idr, ERR_PTR(-EBUSY),
495                                     *index);
496         }
497         spin_unlock(&idrinfo->lock);
498         return ret;
499 }
500 EXPORT_SYMBOL(tcf_idr_check_alloc);
501
502 void tcf_idrinfo_destroy(const struct tc_action_ops *ops,
503                          struct tcf_idrinfo *idrinfo)
504 {
505         struct idr *idr = &idrinfo->action_idr;
506         struct tc_action *p;
507         int ret;
508         unsigned long id = 1;
509
510         idr_for_each_entry_ul(idr, p, id) {
511                 ret = __tcf_idr_release(p, false, true);
512                 if (ret == ACT_P_DELETED)
513                         module_put(ops->owner);
514                 else if (ret < 0)
515                         return;
516         }
517         idr_destroy(&idrinfo->action_idr);
518 }
519 EXPORT_SYMBOL(tcf_idrinfo_destroy);
520
521 static LIST_HEAD(act_base);
522 static DEFINE_RWLOCK(act_mod_lock);
523
524 int tcf_register_action(struct tc_action_ops *act,
525                         struct pernet_operations *ops)
526 {
527         struct tc_action_ops *a;
528         int ret;
529
530         if (!act->act || !act->dump || !act->init || !act->walk || !act->lookup)
531                 return -EINVAL;
532
533         /* We have to register pernet ops before making the action ops visible,
534          * otherwise tcf_action_init_1() could get a partially initialized
535          * netns.
536          */
537         ret = register_pernet_subsys(ops);
538         if (ret)
539                 return ret;
540
541         write_lock(&act_mod_lock);
542         list_for_each_entry(a, &act_base, head) {
543                 if (act->type == a->type || (strcmp(act->kind, a->kind) == 0)) {
544                         write_unlock(&act_mod_lock);
545                         unregister_pernet_subsys(ops);
546                         return -EEXIST;
547                 }
548         }
549         list_add_tail(&act->head, &act_base);
550         write_unlock(&act_mod_lock);
551
552         return 0;
553 }
554 EXPORT_SYMBOL(tcf_register_action);
555
556 int tcf_unregister_action(struct tc_action_ops *act,
557                           struct pernet_operations *ops)
558 {
559         struct tc_action_ops *a;
560         int err = -ENOENT;
561
562         write_lock(&act_mod_lock);
563         list_for_each_entry(a, &act_base, head) {
564                 if (a == act) {
565                         list_del(&act->head);
566                         err = 0;
567                         break;
568                 }
569         }
570         write_unlock(&act_mod_lock);
571         if (!err)
572                 unregister_pernet_subsys(ops);
573         return err;
574 }
575 EXPORT_SYMBOL(tcf_unregister_action);
576
577 /* lookup by name */
578 static struct tc_action_ops *tc_lookup_action_n(char *kind)
579 {
580         struct tc_action_ops *a, *res = NULL;
581
582         if (kind) {
583                 read_lock(&act_mod_lock);
584                 list_for_each_entry(a, &act_base, head) {
585                         if (strcmp(kind, a->kind) == 0) {
586                                 if (try_module_get(a->owner))
587                                         res = a;
588                                 break;
589                         }
590                 }
591                 read_unlock(&act_mod_lock);
592         }
593         return res;
594 }
595
596 /* lookup by nlattr */
597 static struct tc_action_ops *tc_lookup_action(struct nlattr *kind)
598 {
599         struct tc_action_ops *a, *res = NULL;
600
601         if (kind) {
602                 read_lock(&act_mod_lock);
603                 list_for_each_entry(a, &act_base, head) {
604                         if (nla_strcmp(kind, a->kind) == 0) {
605                                 if (try_module_get(a->owner))
606                                         res = a;
607                                 break;
608                         }
609                 }
610                 read_unlock(&act_mod_lock);
611         }
612         return res;
613 }
614
615 /*TCA_ACT_MAX_PRIO is 32, there count upto 32 */
616 #define TCA_ACT_MAX_PRIO_MASK 0x1FF
617 int tcf_action_exec(struct sk_buff *skb, struct tc_action **actions,
618                     int nr_actions, struct tcf_result *res)
619 {
620         u32 jmp_prgcnt = 0;
621         u32 jmp_ttl = TCA_ACT_MAX_PRIO; /*matches actions per filter */
622         int i;
623         int ret = TC_ACT_OK;
624
625         if (skb_skip_tc_classify(skb))
626                 return TC_ACT_OK;
627
628 restart_act_graph:
629         for (i = 0; i < nr_actions; i++) {
630                 const struct tc_action *a = actions[i];
631
632                 if (jmp_prgcnt > 0) {
633                         jmp_prgcnt -= 1;
634                         continue;
635                 }
636 repeat:
637                 ret = a->ops->act(skb, a, res);
638                 if (ret == TC_ACT_REPEAT)
639                         goto repeat;    /* we need a ttl - JHS */
640
641                 if (TC_ACT_EXT_CMP(ret, TC_ACT_JUMP)) {
642                         jmp_prgcnt = ret & TCA_ACT_MAX_PRIO_MASK;
643                         if (!jmp_prgcnt || (jmp_prgcnt > nr_actions)) {
644                                 /* faulty opcode, stop pipeline */
645                                 return TC_ACT_OK;
646                         } else {
647                                 jmp_ttl -= 1;
648                                 if (jmp_ttl > 0)
649                                         goto restart_act_graph;
650                                 else /* faulty graph, stop pipeline */
651                                         return TC_ACT_OK;
652                         }
653                 } else if (TC_ACT_EXT_CMP(ret, TC_ACT_GOTO_CHAIN)) {
654                         tcf_action_goto_chain_exec(a, res);
655                 }
656
657                 if (ret != TC_ACT_PIPE)
658                         break;
659         }
660
661         return ret;
662 }
663 EXPORT_SYMBOL(tcf_action_exec);
664
665 int tcf_action_destroy(struct tc_action *actions[], int bind)
666 {
667         const struct tc_action_ops *ops;
668         struct tc_action *a;
669         int ret = 0, i;
670
671         for (i = 0; i < TCA_ACT_MAX_PRIO && actions[i]; i++) {
672                 a = actions[i];
673                 actions[i] = NULL;
674                 ops = a->ops;
675                 ret = __tcf_idr_release(a, bind, true);
676                 if (ret == ACT_P_DELETED)
677                         module_put(ops->owner);
678                 else if (ret < 0)
679                         return ret;
680         }
681         return ret;
682 }
683
684 static int tcf_action_put(struct tc_action *p)
685 {
686         return __tcf_action_put(p, false);
687 }
688
689 static void tcf_action_put_many(struct tc_action *actions[])
690 {
691         int i;
692
693         for (i = 0; i < TCA_ACT_MAX_PRIO && actions[i]; i++) {
694                 struct tc_action *a = actions[i];
695                 const struct tc_action_ops *ops = a->ops;
696
697                 if (tcf_action_put(a))
698                         module_put(ops->owner);
699         }
700 }
701
702 int
703 tcf_action_dump_old(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
704 {
705         return a->ops->dump(skb, a, bind, ref);
706 }
707
708 int
709 tcf_action_dump_1(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
710 {
711         int err = -EINVAL;
712         unsigned char *b = skb_tail_pointer(skb);
713         struct nlattr *nest;
714         struct tc_cookie *cookie;
715
716         if (nla_put_string(skb, TCA_KIND, a->ops->kind))
717                 goto nla_put_failure;
718         if (tcf_action_copy_stats(skb, a, 0))
719                 goto nla_put_failure;
720
721         rcu_read_lock();
722         cookie = rcu_dereference(a->act_cookie);
723         if (cookie) {
724                 if (nla_put(skb, TCA_ACT_COOKIE, cookie->len, cookie->data)) {
725                         rcu_read_unlock();
726                         goto nla_put_failure;
727                 }
728         }
729         rcu_read_unlock();
730
731         nest = nla_nest_start(skb, TCA_OPTIONS);
732         if (nest == NULL)
733                 goto nla_put_failure;
734         err = tcf_action_dump_old(skb, a, bind, ref);
735         if (err > 0) {
736                 nla_nest_end(skb, nest);
737                 return err;
738         }
739
740 nla_put_failure:
741         nlmsg_trim(skb, b);
742         return -1;
743 }
744 EXPORT_SYMBOL(tcf_action_dump_1);
745
746 int tcf_action_dump(struct sk_buff *skb, struct tc_action *actions[],
747                     int bind, int ref)
748 {
749         struct tc_action *a;
750         int err = -EINVAL, i;
751         struct nlattr *nest;
752
753         for (i = 0; i < TCA_ACT_MAX_PRIO && actions[i]; i++) {
754                 a = actions[i];
755                 nest = nla_nest_start(skb, a->order);
756                 if (nest == NULL)
757                         goto nla_put_failure;
758                 err = tcf_action_dump_1(skb, a, bind, ref);
759                 if (err < 0)
760                         goto errout;
761                 nla_nest_end(skb, nest);
762         }
763
764         return 0;
765
766 nla_put_failure:
767         err = -EINVAL;
768 errout:
769         nla_nest_cancel(skb, nest);
770         return err;
771 }
772
773 static struct tc_cookie *nla_memdup_cookie(struct nlattr **tb)
774 {
775         struct tc_cookie *c = kzalloc(sizeof(*c), GFP_KERNEL);
776         if (!c)
777                 return NULL;
778
779         c->data = nla_memdup(tb[TCA_ACT_COOKIE], GFP_KERNEL);
780         if (!c->data) {
781                 kfree(c);
782                 return NULL;
783         }
784         c->len = nla_len(tb[TCA_ACT_COOKIE]);
785
786         return c;
787 }
788
789 struct tc_action *tcf_action_init_1(struct net *net, struct tcf_proto *tp,
790                                     struct nlattr *nla, struct nlattr *est,
791                                     char *name, int ovr, int bind,
792                                     bool rtnl_held,
793                                     struct netlink_ext_ack *extack)
794 {
795         struct tc_action *a;
796         struct tc_action_ops *a_o;
797         struct tc_cookie *cookie = NULL;
798         char act_name[IFNAMSIZ];
799         struct nlattr *tb[TCA_ACT_MAX + 1];
800         struct nlattr *kind;
801         int err;
802
803         if (name == NULL) {
804                 err = nla_parse_nested(tb, TCA_ACT_MAX, nla, NULL, extack);
805                 if (err < 0)
806                         goto err_out;
807                 err = -EINVAL;
808                 kind = tb[TCA_ACT_KIND];
809                 if (!kind) {
810                         NL_SET_ERR_MSG(extack, "TC action kind must be specified");
811                         goto err_out;
812                 }
813                 if (nla_strlcpy(act_name, kind, IFNAMSIZ) >= IFNAMSIZ) {
814                         NL_SET_ERR_MSG(extack, "TC action name too long");
815                         goto err_out;
816                 }
817                 if (tb[TCA_ACT_COOKIE]) {
818                         int cklen = nla_len(tb[TCA_ACT_COOKIE]);
819
820                         if (cklen > TC_COOKIE_MAX_SIZE) {
821                                 NL_SET_ERR_MSG(extack, "TC cookie size above the maximum");
822                                 goto err_out;
823                         }
824
825                         cookie = nla_memdup_cookie(tb);
826                         if (!cookie) {
827                                 NL_SET_ERR_MSG(extack, "No memory to generate TC cookie");
828                                 err = -ENOMEM;
829                                 goto err_out;
830                         }
831                 }
832         } else {
833                 if (strlcpy(act_name, name, IFNAMSIZ) >= IFNAMSIZ) {
834                         NL_SET_ERR_MSG(extack, "TC action name too long");
835                         err = -EINVAL;
836                         goto err_out;
837                 }
838         }
839
840         a_o = tc_lookup_action_n(act_name);
841         if (a_o == NULL) {
842 #ifdef CONFIG_MODULES
843                 if (rtnl_held)
844                         rtnl_unlock();
845                 request_module("act_%s", act_name);
846                 if (rtnl_held)
847                         rtnl_lock();
848
849                 a_o = tc_lookup_action_n(act_name);
850
851                 /* We dropped the RTNL semaphore in order to
852                  * perform the module load.  So, even if we
853                  * succeeded in loading the module we have to
854                  * tell the caller to replay the request.  We
855                  * indicate this using -EAGAIN.
856                  */
857                 if (a_o != NULL) {
858                         err = -EAGAIN;
859                         goto err_mod;
860                 }
861 #endif
862                 NL_SET_ERR_MSG(extack, "Failed to load TC action module");
863                 err = -ENOENT;
864                 goto err_out;
865         }
866
867         /* backward compatibility for policer */
868         if (name == NULL)
869                 err = a_o->init(net, tb[TCA_ACT_OPTIONS], est, &a, ovr, bind,
870                                 rtnl_held, extack);
871         else
872                 err = a_o->init(net, nla, est, &a, ovr, bind, rtnl_held,
873                                 extack);
874         if (err < 0)
875                 goto err_mod;
876
877         if (!name && tb[TCA_ACT_COOKIE])
878                 tcf_set_action_cookie(&a->act_cookie, cookie);
879
880         /* module count goes up only when brand new policy is created
881          * if it exists and is only bound to in a_o->init() then
882          * ACT_P_CREATED is not returned (a zero is).
883          */
884         if (err != ACT_P_CREATED)
885                 module_put(a_o->owner);
886
887         if (TC_ACT_EXT_CMP(a->tcfa_action, TC_ACT_GOTO_CHAIN)) {
888                 err = tcf_action_goto_chain_init(a, tp);
889                 if (err) {
890                         struct tc_action *actions[] = { a, NULL };
891
892                         tcf_action_destroy(actions, bind);
893                         NL_SET_ERR_MSG(extack, "Failed to init TC action chain");
894                         return ERR_PTR(err);
895                 }
896         }
897
898         return a;
899
900 err_mod:
901         module_put(a_o->owner);
902 err_out:
903         if (cookie) {
904                 kfree(cookie->data);
905                 kfree(cookie);
906         }
907         return ERR_PTR(err);
908 }
909
910 /* Returns numbers of initialized actions or negative error. */
911
912 int tcf_action_init(struct net *net, struct tcf_proto *tp, struct nlattr *nla,
913                     struct nlattr *est, char *name, int ovr, int bind,
914                     struct tc_action *actions[], size_t *attr_size,
915                     bool rtnl_held, struct netlink_ext_ack *extack)
916 {
917         struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
918         struct tc_action *act;
919         size_t sz = 0;
920         int err;
921         int i;
922
923         err = nla_parse_nested(tb, TCA_ACT_MAX_PRIO, nla, NULL, extack);
924         if (err < 0)
925                 return err;
926
927         for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
928                 act = tcf_action_init_1(net, tp, tb[i], est, name, ovr, bind,
929                                         rtnl_held, extack);
930                 if (IS_ERR(act)) {
931                         err = PTR_ERR(act);
932                         goto err;
933                 }
934                 act->order = i;
935                 sz += tcf_action_fill_size(act);
936                 /* Start from index 0 */
937                 actions[i - 1] = act;
938         }
939
940         *attr_size = tcf_action_full_attrs_size(sz);
941         return i - 1;
942
943 err:
944         tcf_action_destroy(actions, bind);
945         return err;
946 }
947
948 int tcf_action_copy_stats(struct sk_buff *skb, struct tc_action *p,
949                           int compat_mode)
950 {
951         int err = 0;
952         struct gnet_dump d;
953
954         if (p == NULL)
955                 goto errout;
956
957         /* compat_mode being true specifies a call that is supposed
958          * to add additional backward compatibility statistic TLVs.
959          */
960         if (compat_mode) {
961                 if (p->type == TCA_OLD_COMPAT)
962                         err = gnet_stats_start_copy_compat(skb, 0,
963                                                            TCA_STATS,
964                                                            TCA_XSTATS,
965                                                            &p->tcfa_lock, &d,
966                                                            TCA_PAD);
967                 else
968                         return 0;
969         } else
970                 err = gnet_stats_start_copy(skb, TCA_ACT_STATS,
971                                             &p->tcfa_lock, &d, TCA_ACT_PAD);
972
973         if (err < 0)
974                 goto errout;
975
976         if (gnet_stats_copy_basic(NULL, &d, p->cpu_bstats, &p->tcfa_bstats) < 0 ||
977             gnet_stats_copy_rate_est(&d, &p->tcfa_rate_est) < 0 ||
978             gnet_stats_copy_queue(&d, p->cpu_qstats,
979                                   &p->tcfa_qstats,
980                                   p->tcfa_qstats.qlen) < 0)
981                 goto errout;
982
983         if (gnet_stats_finish_copy(&d) < 0)
984                 goto errout;
985
986         return 0;
987
988 errout:
989         return -1;
990 }
991
992 static int tca_get_fill(struct sk_buff *skb, struct tc_action *actions[],
993                         u32 portid, u32 seq, u16 flags, int event, int bind,
994                         int ref)
995 {
996         struct tcamsg *t;
997         struct nlmsghdr *nlh;
998         unsigned char *b = skb_tail_pointer(skb);
999         struct nlattr *nest;
1000
1001         nlh = nlmsg_put(skb, portid, seq, event, sizeof(*t), flags);
1002         if (!nlh)
1003                 goto out_nlmsg_trim;
1004         t = nlmsg_data(nlh);
1005         t->tca_family = AF_UNSPEC;
1006         t->tca__pad1 = 0;
1007         t->tca__pad2 = 0;
1008
1009         nest = nla_nest_start(skb, TCA_ACT_TAB);
1010         if (!nest)
1011                 goto out_nlmsg_trim;
1012
1013         if (tcf_action_dump(skb, actions, bind, ref) < 0)
1014                 goto out_nlmsg_trim;
1015
1016         nla_nest_end(skb, nest);
1017
1018         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1019         return skb->len;
1020
1021 out_nlmsg_trim:
1022         nlmsg_trim(skb, b);
1023         return -1;
1024 }
1025
1026 static int
1027 tcf_get_notify(struct net *net, u32 portid, struct nlmsghdr *n,
1028                struct tc_action *actions[], int event,
1029                struct netlink_ext_ack *extack)
1030 {
1031         struct sk_buff *skb;
1032
1033         skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1034         if (!skb)
1035                 return -ENOBUFS;
1036         if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, 0, event,
1037                          0, 1) <= 0) {
1038                 NL_SET_ERR_MSG(extack, "Failed to fill netlink attributes while adding TC action");
1039                 kfree_skb(skb);
1040                 return -EINVAL;
1041         }
1042
1043         return rtnl_unicast(skb, net, portid);
1044 }
1045
1046 static struct tc_action *tcf_action_get_1(struct net *net, struct nlattr *nla,
1047                                           struct nlmsghdr *n, u32 portid,
1048                                           struct netlink_ext_ack *extack)
1049 {
1050         struct nlattr *tb[TCA_ACT_MAX + 1];
1051         const struct tc_action_ops *ops;
1052         struct tc_action *a;
1053         int index;
1054         int err;
1055
1056         err = nla_parse_nested(tb, TCA_ACT_MAX, nla, NULL, extack);
1057         if (err < 0)
1058                 goto err_out;
1059
1060         err = -EINVAL;
1061         if (tb[TCA_ACT_INDEX] == NULL ||
1062             nla_len(tb[TCA_ACT_INDEX]) < sizeof(index)) {
1063                 NL_SET_ERR_MSG(extack, "Invalid TC action index value");
1064                 goto err_out;
1065         }
1066         index = nla_get_u32(tb[TCA_ACT_INDEX]);
1067
1068         err = -EINVAL;
1069         ops = tc_lookup_action(tb[TCA_ACT_KIND]);
1070         if (!ops) { /* could happen in batch of actions */
1071                 NL_SET_ERR_MSG(extack, "Specified TC action not found");
1072                 goto err_out;
1073         }
1074         err = -ENOENT;
1075         if (ops->lookup(net, &a, index, extack) == 0)
1076                 goto err_mod;
1077
1078         module_put(ops->owner);
1079         return a;
1080
1081 err_mod:
1082         module_put(ops->owner);
1083 err_out:
1084         return ERR_PTR(err);
1085 }
1086
1087 static int tca_action_flush(struct net *net, struct nlattr *nla,
1088                             struct nlmsghdr *n, u32 portid,
1089                             struct netlink_ext_ack *extack)
1090 {
1091         struct sk_buff *skb;
1092         unsigned char *b;
1093         struct nlmsghdr *nlh;
1094         struct tcamsg *t;
1095         struct netlink_callback dcb;
1096         struct nlattr *nest;
1097         struct nlattr *tb[TCA_ACT_MAX + 1];
1098         const struct tc_action_ops *ops;
1099         struct nlattr *kind;
1100         int err = -ENOMEM;
1101
1102         skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1103         if (!skb)
1104                 return err;
1105
1106         b = skb_tail_pointer(skb);
1107
1108         err = nla_parse_nested(tb, TCA_ACT_MAX, nla, NULL, extack);
1109         if (err < 0)
1110                 goto err_out;
1111
1112         err = -EINVAL;
1113         kind = tb[TCA_ACT_KIND];
1114         ops = tc_lookup_action(kind);
1115         if (!ops) { /*some idjot trying to flush unknown action */
1116                 NL_SET_ERR_MSG(extack, "Cannot flush unknown TC action");
1117                 goto err_out;
1118         }
1119
1120         nlh = nlmsg_put(skb, portid, n->nlmsg_seq, RTM_DELACTION,
1121                         sizeof(*t), 0);
1122         if (!nlh) {
1123                 NL_SET_ERR_MSG(extack, "Failed to create TC action flush notification");
1124                 goto out_module_put;
1125         }
1126         t = nlmsg_data(nlh);
1127         t->tca_family = AF_UNSPEC;
1128         t->tca__pad1 = 0;
1129         t->tca__pad2 = 0;
1130
1131         nest = nla_nest_start(skb, TCA_ACT_TAB);
1132         if (!nest) {
1133                 NL_SET_ERR_MSG(extack, "Failed to add new netlink message");
1134                 goto out_module_put;
1135         }
1136
1137         err = ops->walk(net, skb, &dcb, RTM_DELACTION, ops, extack);
1138         if (err <= 0) {
1139                 nla_nest_cancel(skb, nest);
1140                 goto out_module_put;
1141         }
1142
1143         nla_nest_end(skb, nest);
1144
1145         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1146         nlh->nlmsg_flags |= NLM_F_ROOT;
1147         module_put(ops->owner);
1148         err = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
1149                              n->nlmsg_flags & NLM_F_ECHO);
1150         if (err > 0)
1151                 return 0;
1152         if (err < 0)
1153                 NL_SET_ERR_MSG(extack, "Failed to send TC action flush notification");
1154
1155         return err;
1156
1157 out_module_put:
1158         module_put(ops->owner);
1159 err_out:
1160         kfree_skb(skb);
1161         return err;
1162 }
1163
1164 static int tcf_action_delete(struct net *net, struct tc_action *actions[],
1165                              int *acts_deleted, struct netlink_ext_ack *extack)
1166 {
1167         u32 act_index;
1168         int ret, i;
1169
1170         for (i = 0; i < TCA_ACT_MAX_PRIO && actions[i]; i++) {
1171                 struct tc_action *a = actions[i];
1172                 const struct tc_action_ops *ops = a->ops;
1173
1174                 /* Actions can be deleted concurrently so we must save their
1175                  * type and id to search again after reference is released.
1176                  */
1177                 act_index = a->tcfa_index;
1178
1179                 if (tcf_action_put(a)) {
1180                         /* last reference, action was deleted concurrently */
1181                         module_put(ops->owner);
1182                 } else  {
1183                         /* now do the delete */
1184                         ret = ops->delete(net, act_index);
1185                         if (ret < 0) {
1186                                 *acts_deleted = i + 1;
1187                                 return ret;
1188                         }
1189                 }
1190         }
1191         *acts_deleted = i;
1192         return 0;
1193 }
1194
1195 static int
1196 tcf_del_notify(struct net *net, struct nlmsghdr *n, struct tc_action *actions[],
1197                int *acts_deleted, u32 portid, size_t attr_size,
1198                struct netlink_ext_ack *extack)
1199 {
1200         int ret;
1201         struct sk_buff *skb;
1202
1203         skb = alloc_skb(attr_size <= NLMSG_GOODSIZE ? NLMSG_GOODSIZE : attr_size,
1204                         GFP_KERNEL);
1205         if (!skb)
1206                 return -ENOBUFS;
1207
1208         if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, 0, RTM_DELACTION,
1209                          0, 2) <= 0) {
1210                 NL_SET_ERR_MSG(extack, "Failed to fill netlink TC action attributes");
1211                 kfree_skb(skb);
1212                 return -EINVAL;
1213         }
1214
1215         /* now do the delete */
1216         ret = tcf_action_delete(net, actions, acts_deleted, extack);
1217         if (ret < 0) {
1218                 NL_SET_ERR_MSG(extack, "Failed to delete TC action");
1219                 kfree_skb(skb);
1220                 return ret;
1221         }
1222
1223         ret = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
1224                              n->nlmsg_flags & NLM_F_ECHO);
1225         if (ret > 0)
1226                 return 0;
1227         return ret;
1228 }
1229
1230 static int
1231 tca_action_gd(struct net *net, struct nlattr *nla, struct nlmsghdr *n,
1232               u32 portid, int event, struct netlink_ext_ack *extack)
1233 {
1234         int i, ret;
1235         struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
1236         struct tc_action *act;
1237         size_t attr_size = 0;
1238         struct tc_action *actions[TCA_ACT_MAX_PRIO + 1] = {};
1239         int acts_deleted = 0;
1240
1241         ret = nla_parse_nested(tb, TCA_ACT_MAX_PRIO, nla, NULL, extack);
1242         if (ret < 0)
1243                 return ret;
1244
1245         if (event == RTM_DELACTION && n->nlmsg_flags & NLM_F_ROOT) {
1246                 if (tb[1])
1247                         return tca_action_flush(net, tb[1], n, portid, extack);
1248
1249                 NL_SET_ERR_MSG(extack, "Invalid netlink attributes while flushing TC action");
1250                 return -EINVAL;
1251         }
1252
1253         for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
1254                 act = tcf_action_get_1(net, tb[i], n, portid, extack);
1255                 if (IS_ERR(act)) {
1256                         ret = PTR_ERR(act);
1257                         goto err;
1258                 }
1259                 act->order = i;
1260                 attr_size += tcf_action_fill_size(act);
1261                 actions[i - 1] = act;
1262         }
1263
1264         attr_size = tcf_action_full_attrs_size(attr_size);
1265
1266         if (event == RTM_GETACTION)
1267                 ret = tcf_get_notify(net, portid, n, actions, event, extack);
1268         else { /* delete */
1269                 ret = tcf_del_notify(net, n, actions, &acts_deleted, portid,
1270                                      attr_size, extack);
1271                 if (ret)
1272                         goto err;
1273                 return ret;
1274         }
1275 err:
1276         tcf_action_put_many(&actions[acts_deleted]);
1277         return ret;
1278 }
1279
1280 static int
1281 tcf_add_notify(struct net *net, struct nlmsghdr *n, struct tc_action *actions[],
1282                u32 portid, size_t attr_size, struct netlink_ext_ack *extack)
1283 {
1284         struct sk_buff *skb;
1285         int err = 0;
1286
1287         skb = alloc_skb(attr_size <= NLMSG_GOODSIZE ? NLMSG_GOODSIZE : attr_size,
1288                         GFP_KERNEL);
1289         if (!skb)
1290                 return -ENOBUFS;
1291
1292         if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, n->nlmsg_flags,
1293                          RTM_NEWACTION, 0, 0) <= 0) {
1294                 NL_SET_ERR_MSG(extack, "Failed to fill netlink attributes while adding TC action");
1295                 kfree_skb(skb);
1296                 return -EINVAL;
1297         }
1298
1299         err = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
1300                              n->nlmsg_flags & NLM_F_ECHO);
1301         if (err > 0)
1302                 err = 0;
1303         return err;
1304 }
1305
1306 static int tcf_action_add(struct net *net, struct nlattr *nla,
1307                           struct nlmsghdr *n, u32 portid, int ovr,
1308                           struct netlink_ext_ack *extack)
1309 {
1310         size_t attr_size = 0;
1311         int ret = 0;
1312         struct tc_action *actions[TCA_ACT_MAX_PRIO] = {};
1313
1314         ret = tcf_action_init(net, NULL, nla, NULL, NULL, ovr, 0, actions,
1315                               &attr_size, true, extack);
1316         if (ret < 0)
1317                 return ret;
1318         ret = tcf_add_notify(net, n, actions, portid, attr_size, extack);
1319         if (ovr)
1320                 tcf_action_put_many(actions);
1321
1322         return ret;
1323 }
1324
1325 static u32 tcaa_root_flags_allowed = TCA_FLAG_LARGE_DUMP_ON;
1326 static const struct nla_policy tcaa_policy[TCA_ROOT_MAX + 1] = {
1327         [TCA_ROOT_FLAGS] = { .type = NLA_BITFIELD32,
1328                              .validation_data = &tcaa_root_flags_allowed },
1329         [TCA_ROOT_TIME_DELTA]      = { .type = NLA_U32 },
1330 };
1331
1332 static int tc_ctl_action(struct sk_buff *skb, struct nlmsghdr *n,
1333                          struct netlink_ext_ack *extack)
1334 {
1335         struct net *net = sock_net(skb->sk);
1336         struct nlattr *tca[TCA_ROOT_MAX + 1];
1337         u32 portid = skb ? NETLINK_CB(skb).portid : 0;
1338         int ret = 0, ovr = 0;
1339
1340         if ((n->nlmsg_type != RTM_GETACTION) &&
1341             !netlink_capable(skb, CAP_NET_ADMIN))
1342                 return -EPERM;
1343
1344         ret = nlmsg_parse(n, sizeof(struct tcamsg), tca, TCA_ROOT_MAX, NULL,
1345                           extack);
1346         if (ret < 0)
1347                 return ret;
1348
1349         if (tca[TCA_ACT_TAB] == NULL) {
1350                 NL_SET_ERR_MSG(extack, "Netlink action attributes missing");
1351                 return -EINVAL;
1352         }
1353
1354         /* n->nlmsg_flags & NLM_F_CREATE */
1355         switch (n->nlmsg_type) {
1356         case RTM_NEWACTION:
1357                 /* we are going to assume all other flags
1358                  * imply create only if it doesn't exist
1359                  * Note that CREATE | EXCL implies that
1360                  * but since we want avoid ambiguity (eg when flags
1361                  * is zero) then just set this
1362                  */
1363                 if (n->nlmsg_flags & NLM_F_REPLACE)
1364                         ovr = 1;
1365 replay:
1366                 ret = tcf_action_add(net, tca[TCA_ACT_TAB], n, portid, ovr,
1367                                      extack);
1368                 if (ret == -EAGAIN)
1369                         goto replay;
1370                 break;
1371         case RTM_DELACTION:
1372                 ret = tca_action_gd(net, tca[TCA_ACT_TAB], n,
1373                                     portid, RTM_DELACTION, extack);
1374                 break;
1375         case RTM_GETACTION:
1376                 ret = tca_action_gd(net, tca[TCA_ACT_TAB], n,
1377                                     portid, RTM_GETACTION, extack);
1378                 break;
1379         default:
1380                 BUG();
1381         }
1382
1383         return ret;
1384 }
1385
1386 static struct nlattr *find_dump_kind(struct nlattr **nla)
1387 {
1388         struct nlattr *tb1, *tb2[TCA_ACT_MAX + 1];
1389         struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
1390         struct nlattr *kind;
1391
1392         tb1 = nla[TCA_ACT_TAB];
1393         if (tb1 == NULL)
1394                 return NULL;
1395
1396         if (nla_parse(tb, TCA_ACT_MAX_PRIO, nla_data(tb1),
1397                       NLMSG_ALIGN(nla_len(tb1)), NULL, NULL) < 0)
1398                 return NULL;
1399
1400         if (tb[1] == NULL)
1401                 return NULL;
1402         if (nla_parse_nested(tb2, TCA_ACT_MAX, tb[1], NULL, NULL) < 0)
1403                 return NULL;
1404         kind = tb2[TCA_ACT_KIND];
1405
1406         return kind;
1407 }
1408
1409 static int tc_dump_action(struct sk_buff *skb, struct netlink_callback *cb)
1410 {
1411         struct net *net = sock_net(skb->sk);
1412         struct nlmsghdr *nlh;
1413         unsigned char *b = skb_tail_pointer(skb);
1414         struct nlattr *nest;
1415         struct tc_action_ops *a_o;
1416         int ret = 0;
1417         struct tcamsg *t = (struct tcamsg *) nlmsg_data(cb->nlh);
1418         struct nlattr *tb[TCA_ROOT_MAX + 1];
1419         struct nlattr *count_attr = NULL;
1420         unsigned long jiffy_since = 0;
1421         struct nlattr *kind = NULL;
1422         struct nla_bitfield32 bf;
1423         u32 msecs_since = 0;
1424         u32 act_count = 0;
1425
1426         ret = nlmsg_parse(cb->nlh, sizeof(struct tcamsg), tb, TCA_ROOT_MAX,
1427                           tcaa_policy, NULL);
1428         if (ret < 0)
1429                 return ret;
1430
1431         kind = find_dump_kind(tb);
1432         if (kind == NULL) {
1433                 pr_info("tc_dump_action: action bad kind\n");
1434                 return 0;
1435         }
1436
1437         a_o = tc_lookup_action(kind);
1438         if (a_o == NULL)
1439                 return 0;
1440
1441         cb->args[2] = 0;
1442         if (tb[TCA_ROOT_FLAGS]) {
1443                 bf = nla_get_bitfield32(tb[TCA_ROOT_FLAGS]);
1444                 cb->args[2] = bf.value;
1445         }
1446
1447         if (tb[TCA_ROOT_TIME_DELTA]) {
1448                 msecs_since = nla_get_u32(tb[TCA_ROOT_TIME_DELTA]);
1449         }
1450
1451         nlh = nlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
1452                         cb->nlh->nlmsg_type, sizeof(*t), 0);
1453         if (!nlh)
1454                 goto out_module_put;
1455
1456         if (msecs_since)
1457                 jiffy_since = jiffies - msecs_to_jiffies(msecs_since);
1458
1459         t = nlmsg_data(nlh);
1460         t->tca_family = AF_UNSPEC;
1461         t->tca__pad1 = 0;
1462         t->tca__pad2 = 0;
1463         cb->args[3] = jiffy_since;
1464         count_attr = nla_reserve(skb, TCA_ROOT_COUNT, sizeof(u32));
1465         if (!count_attr)
1466                 goto out_module_put;
1467
1468         nest = nla_nest_start(skb, TCA_ACT_TAB);
1469         if (nest == NULL)
1470                 goto out_module_put;
1471
1472         ret = a_o->walk(net, skb, cb, RTM_GETACTION, a_o, NULL);
1473         if (ret < 0)
1474                 goto out_module_put;
1475
1476         if (ret > 0) {
1477                 nla_nest_end(skb, nest);
1478                 ret = skb->len;
1479                 act_count = cb->args[1];
1480                 memcpy(nla_data(count_attr), &act_count, sizeof(u32));
1481                 cb->args[1] = 0;
1482         } else
1483                 nlmsg_trim(skb, b);
1484
1485         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1486         if (NETLINK_CB(cb->skb).portid && ret)
1487                 nlh->nlmsg_flags |= NLM_F_MULTI;
1488         module_put(a_o->owner);
1489         return skb->len;
1490
1491 out_module_put:
1492         module_put(a_o->owner);
1493         nlmsg_trim(skb, b);
1494         return skb->len;
1495 }
1496
1497 struct tcf_action_net {
1498         struct rhashtable egdev_ht;
1499 };
1500
1501 static unsigned int tcf_action_net_id;
1502
1503 struct tcf_action_egdev_cb {
1504         struct list_head list;
1505         tc_setup_cb_t *cb;
1506         void *cb_priv;
1507 };
1508
1509 struct tcf_action_egdev {
1510         struct rhash_head ht_node;
1511         const struct net_device *dev;
1512         unsigned int refcnt;
1513         struct list_head cb_list;
1514 };
1515
1516 static const struct rhashtable_params tcf_action_egdev_ht_params = {
1517         .key_offset = offsetof(struct tcf_action_egdev, dev),
1518         .head_offset = offsetof(struct tcf_action_egdev, ht_node),
1519         .key_len = sizeof(const struct net_device *),
1520 };
1521
1522 static struct tcf_action_egdev *
1523 tcf_action_egdev_lookup(const struct net_device *dev)
1524 {
1525         struct net *net = dev_net(dev);
1526         struct tcf_action_net *tan = net_generic(net, tcf_action_net_id);
1527
1528         return rhashtable_lookup_fast(&tan->egdev_ht, &dev,
1529                                       tcf_action_egdev_ht_params);
1530 }
1531
1532 static struct tcf_action_egdev *
1533 tcf_action_egdev_get(const struct net_device *dev)
1534 {
1535         struct tcf_action_egdev *egdev;
1536         struct tcf_action_net *tan;
1537
1538         egdev = tcf_action_egdev_lookup(dev);
1539         if (egdev)
1540                 goto inc_ref;
1541
1542         egdev = kzalloc(sizeof(*egdev), GFP_KERNEL);
1543         if (!egdev)
1544                 return NULL;
1545         INIT_LIST_HEAD(&egdev->cb_list);
1546         egdev->dev = dev;
1547         tan = net_generic(dev_net(dev), tcf_action_net_id);
1548         rhashtable_insert_fast(&tan->egdev_ht, &egdev->ht_node,
1549                                tcf_action_egdev_ht_params);
1550
1551 inc_ref:
1552         egdev->refcnt++;
1553         return egdev;
1554 }
1555
1556 static void tcf_action_egdev_put(struct tcf_action_egdev *egdev)
1557 {
1558         struct tcf_action_net *tan;
1559
1560         if (--egdev->refcnt)
1561                 return;
1562         tan = net_generic(dev_net(egdev->dev), tcf_action_net_id);
1563         rhashtable_remove_fast(&tan->egdev_ht, &egdev->ht_node,
1564                                tcf_action_egdev_ht_params);
1565         kfree(egdev);
1566 }
1567
1568 static struct tcf_action_egdev_cb *
1569 tcf_action_egdev_cb_lookup(struct tcf_action_egdev *egdev,
1570                            tc_setup_cb_t *cb, void *cb_priv)
1571 {
1572         struct tcf_action_egdev_cb *egdev_cb;
1573
1574         list_for_each_entry(egdev_cb, &egdev->cb_list, list)
1575                 if (egdev_cb->cb == cb && egdev_cb->cb_priv == cb_priv)
1576                         return egdev_cb;
1577         return NULL;
1578 }
1579
1580 static int tcf_action_egdev_cb_call(struct tcf_action_egdev *egdev,
1581                                     enum tc_setup_type type,
1582                                     void *type_data, bool err_stop)
1583 {
1584         struct tcf_action_egdev_cb *egdev_cb;
1585         int ok_count = 0;
1586         int err;
1587
1588         list_for_each_entry(egdev_cb, &egdev->cb_list, list) {
1589                 err = egdev_cb->cb(type, type_data, egdev_cb->cb_priv);
1590                 if (err) {
1591                         if (err_stop)
1592                                 return err;
1593                 } else {
1594                         ok_count++;
1595                 }
1596         }
1597         return ok_count;
1598 }
1599
1600 static int tcf_action_egdev_cb_add(struct tcf_action_egdev *egdev,
1601                                    tc_setup_cb_t *cb, void *cb_priv)
1602 {
1603         struct tcf_action_egdev_cb *egdev_cb;
1604
1605         egdev_cb = tcf_action_egdev_cb_lookup(egdev, cb, cb_priv);
1606         if (WARN_ON(egdev_cb))
1607                 return -EEXIST;
1608         egdev_cb = kzalloc(sizeof(*egdev_cb), GFP_KERNEL);
1609         if (!egdev_cb)
1610                 return -ENOMEM;
1611         egdev_cb->cb = cb;
1612         egdev_cb->cb_priv = cb_priv;
1613         list_add(&egdev_cb->list, &egdev->cb_list);
1614         return 0;
1615 }
1616
1617 static void tcf_action_egdev_cb_del(struct tcf_action_egdev *egdev,
1618                                     tc_setup_cb_t *cb, void *cb_priv)
1619 {
1620         struct tcf_action_egdev_cb *egdev_cb;
1621
1622         egdev_cb = tcf_action_egdev_cb_lookup(egdev, cb, cb_priv);
1623         if (WARN_ON(!egdev_cb))
1624                 return;
1625         list_del(&egdev_cb->list);
1626         kfree(egdev_cb);
1627 }
1628
1629 static int __tc_setup_cb_egdev_register(const struct net_device *dev,
1630                                         tc_setup_cb_t *cb, void *cb_priv)
1631 {
1632         struct tcf_action_egdev *egdev = tcf_action_egdev_get(dev);
1633         int err;
1634
1635         if (!egdev)
1636                 return -ENOMEM;
1637         err = tcf_action_egdev_cb_add(egdev, cb, cb_priv);
1638         if (err)
1639                 goto err_cb_add;
1640         return 0;
1641
1642 err_cb_add:
1643         tcf_action_egdev_put(egdev);
1644         return err;
1645 }
1646 int tc_setup_cb_egdev_register(const struct net_device *dev,
1647                                tc_setup_cb_t *cb, void *cb_priv)
1648 {
1649         int err;
1650
1651         rtnl_lock();
1652         err = __tc_setup_cb_egdev_register(dev, cb, cb_priv);
1653         rtnl_unlock();
1654         return err;
1655 }
1656 EXPORT_SYMBOL_GPL(tc_setup_cb_egdev_register);
1657
1658 static void __tc_setup_cb_egdev_unregister(const struct net_device *dev,
1659                                            tc_setup_cb_t *cb, void *cb_priv)
1660 {
1661         struct tcf_action_egdev *egdev = tcf_action_egdev_lookup(dev);
1662
1663         if (WARN_ON(!egdev))
1664                 return;
1665         tcf_action_egdev_cb_del(egdev, cb, cb_priv);
1666         tcf_action_egdev_put(egdev);
1667 }
1668 void tc_setup_cb_egdev_unregister(const struct net_device *dev,
1669                                   tc_setup_cb_t *cb, void *cb_priv)
1670 {
1671         rtnl_lock();
1672         __tc_setup_cb_egdev_unregister(dev, cb, cb_priv);
1673         rtnl_unlock();
1674 }
1675 EXPORT_SYMBOL_GPL(tc_setup_cb_egdev_unregister);
1676
1677 int tc_setup_cb_egdev_call(const struct net_device *dev,
1678                            enum tc_setup_type type, void *type_data,
1679                            bool err_stop)
1680 {
1681         struct tcf_action_egdev *egdev = tcf_action_egdev_lookup(dev);
1682
1683         if (!egdev)
1684                 return 0;
1685         return tcf_action_egdev_cb_call(egdev, type, type_data, err_stop);
1686 }
1687 EXPORT_SYMBOL_GPL(tc_setup_cb_egdev_call);
1688
1689 static __net_init int tcf_action_net_init(struct net *net)
1690 {
1691         struct tcf_action_net *tan = net_generic(net, tcf_action_net_id);
1692
1693         return rhashtable_init(&tan->egdev_ht, &tcf_action_egdev_ht_params);
1694 }
1695
1696 static void __net_exit tcf_action_net_exit(struct net *net)
1697 {
1698         struct tcf_action_net *tan = net_generic(net, tcf_action_net_id);
1699
1700         rhashtable_destroy(&tan->egdev_ht);
1701 }
1702
1703 static struct pernet_operations tcf_action_net_ops = {
1704         .init = tcf_action_net_init,
1705         .exit = tcf_action_net_exit,
1706         .id = &tcf_action_net_id,
1707         .size = sizeof(struct tcf_action_net),
1708 };
1709
1710 static int __init tc_action_init(void)
1711 {
1712         int err;
1713
1714         err = register_pernet_subsys(&tcf_action_net_ops);
1715         if (err)
1716                 return err;
1717
1718         rtnl_register(PF_UNSPEC, RTM_NEWACTION, tc_ctl_action, NULL, 0);
1719         rtnl_register(PF_UNSPEC, RTM_DELACTION, tc_ctl_action, NULL, 0);
1720         rtnl_register(PF_UNSPEC, RTM_GETACTION, tc_ctl_action, tc_dump_action,
1721                       0);
1722
1723         return 0;
1724 }
1725
1726 subsys_initcall(tc_action_init);