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Linux 5.7.7
[linux/fpc-iii.git] / net / sched / cls_api.c
blob0a7ecc292bd31b6dbbc98c2c8ef29d86745f7656
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * net/sched/cls_api.c Packet classifier API.
4 *
5 * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
6 *
7 * Changes:
8 *
9 * Eduardo J. Blanco <ejbs@netlabs.com.uy> :990222: kmod support
10 */
11
12 #include <linux/module.h>
13 #include <linux/types.h>
14 #include <linux/kernel.h>
15 #include <linux/string.h>
16 #include <linux/errno.h>
17 #include <linux/err.h>
18 #include <linux/skbuff.h>
19 #include <linux/init.h>
20 #include <linux/kmod.h>
21 #include <linux/slab.h>
22 #include <linux/idr.h>
23 #include <linux/rhashtable.h>
24 #include <linux/jhash.h>
25 #include <linux/rculist.h>
26 #include <net/net_namespace.h>
27 #include <net/sock.h>
28 #include <net/netlink.h>
29 #include <net/pkt_sched.h>
30 #include <net/pkt_cls.h>
31 #include <net/tc_act/tc_pedit.h>
32 #include <net/tc_act/tc_mirred.h>
33 #include <net/tc_act/tc_vlan.h>
34 #include <net/tc_act/tc_tunnel_key.h>
35 #include <net/tc_act/tc_csum.h>
36 #include <net/tc_act/tc_gact.h>
37 #include <net/tc_act/tc_police.h>
38 #include <net/tc_act/tc_sample.h>
39 #include <net/tc_act/tc_skbedit.h>
40 #include <net/tc_act/tc_ct.h>
41 #include <net/tc_act/tc_mpls.h>
42 #include <net/flow_offload.h>
43
44 extern const struct nla_policy rtm_tca_policy[TCA_MAX + 1];
45
46 /* The list of all installed classifier types */
47 static LIST_HEAD(tcf_proto_base);
48
49 /* Protects list of registered TC modules. It is pure SMP lock. */
50 static DEFINE_RWLOCK(cls_mod_lock);
51
52 static u32 destroy_obj_hashfn(const struct tcf_proto *tp)
53 {
54 return jhash_3words(tp->chain->index, tp->prio,
55 (__force __u32)tp->protocol, 0);
56 }
57
58 static void tcf_proto_signal_destroying(struct tcf_chain *chain,
59 struct tcf_proto *tp)
60 {
61 struct tcf_block *block = chain->block;
62
63 mutex_lock(&block->proto_destroy_lock);
64 hash_add_rcu(block->proto_destroy_ht, &tp->destroy_ht_node,
65 destroy_obj_hashfn(tp));
66 mutex_unlock(&block->proto_destroy_lock);
67 }
68
69 static bool tcf_proto_cmp(const struct tcf_proto *tp1,
70 const struct tcf_proto *tp2)
71 {
72 return tp1->chain->index == tp2->chain->index &&
73 tp1->prio == tp2->prio &&
74 tp1->protocol == tp2->protocol;
75 }
76
77 static bool tcf_proto_exists_destroying(struct tcf_chain *chain,
78 struct tcf_proto *tp)
79 {
80 u32 hash = destroy_obj_hashfn(tp);
81 struct tcf_proto *iter;
82 bool found = false;
83
84 rcu_read_lock();
85 hash_for_each_possible_rcu(chain->block->proto_destroy_ht, iter,
86 destroy_ht_node, hash) {
87 if (tcf_proto_cmp(tp, iter)) {
88 found = true;
89 break;
90 }
91 }
92 rcu_read_unlock();
93
94 return found;
95 }
96
97 static void
98 tcf_proto_signal_destroyed(struct tcf_chain *chain, struct tcf_proto *tp)
99 {
100 struct tcf_block *block = chain->block;
101
102 mutex_lock(&block->proto_destroy_lock);
103 if (hash_hashed(&tp->destroy_ht_node))
104 hash_del_rcu(&tp->destroy_ht_node);
105 mutex_unlock(&block->proto_destroy_lock);
106 }
107
108 /* Find classifier type by string name */
109
110 static const struct tcf_proto_ops *__tcf_proto_lookup_ops(const char *kind)
111 {
112 const struct tcf_proto_ops *t, *res = NULL;
113
114 if (kind) {
115 read_lock(&cls_mod_lock);
116 list_for_each_entry(t, &tcf_proto_base, head) {
117 if (strcmp(kind, t->kind) == 0) {
118 if (try_module_get(t->owner))
119 res = t;
120 break;
121 }
122 }
123 read_unlock(&cls_mod_lock);
124 }
125 return res;
126 }
127
128 static const struct tcf_proto_ops *
129 tcf_proto_lookup_ops(const char *kind, bool rtnl_held,
130 struct netlink_ext_ack *extack)
131 {
132 const struct tcf_proto_ops *ops;
133
134 ops = __tcf_proto_lookup_ops(kind);
135 if (ops)
136 return ops;
137 #ifdef CONFIG_MODULES
138 if (rtnl_held)
139 rtnl_unlock();
140 request_module("cls_%s", kind);
141 if (rtnl_held)
142 rtnl_lock();
143 ops = __tcf_proto_lookup_ops(kind);
144 /* We dropped the RTNL semaphore in order to perform
145 * the module load. So, even if we succeeded in loading
146 * the module we have to replay the request. We indicate
147 * this using -EAGAIN.
148 */
149 if (ops) {
150 module_put(ops->owner);
151 return ERR_PTR(-EAGAIN);
152 }
153 #endif
154 NL_SET_ERR_MSG(extack, "TC classifier not found");
155 return ERR_PTR(-ENOENT);
156 }
157
158 /* Register(unregister) new classifier type */
159
160 int register_tcf_proto_ops(struct tcf_proto_ops *ops)
161 {
162 struct tcf_proto_ops *t;
163 int rc = -EEXIST;
164
165 write_lock(&cls_mod_lock);
166 list_for_each_entry(t, &tcf_proto_base, head)
167 if (!strcmp(ops->kind, t->kind))
168 goto out;
169
170 list_add_tail(&ops->head, &tcf_proto_base);
171 rc = 0;
172 out:
173 write_unlock(&cls_mod_lock);
174 return rc;
175 }
176 EXPORT_SYMBOL(register_tcf_proto_ops);
177
178 static struct workqueue_struct *tc_filter_wq;
179
180 int unregister_tcf_proto_ops(struct tcf_proto_ops *ops)
181 {
182 struct tcf_proto_ops *t;
183 int rc = -ENOENT;
184
185 /* Wait for outstanding call_rcu()s, if any, from a
186 * tcf_proto_ops's destroy() handler.
187 */
188 rcu_barrier();
189 flush_workqueue(tc_filter_wq);
190
191 write_lock(&cls_mod_lock);
192 list_for_each_entry(t, &tcf_proto_base, head) {
193 if (t == ops) {
194 list_del(&t->head);
195 rc = 0;
196 break;
197 }
198 }
199 write_unlock(&cls_mod_lock);
200 return rc;
201 }
202 EXPORT_SYMBOL(unregister_tcf_proto_ops);
203
204 bool tcf_queue_work(struct rcu_work *rwork, work_func_t func)
205 {
206 INIT_RCU_WORK(rwork, func);
207 return queue_rcu_work(tc_filter_wq, rwork);
208 }
209 EXPORT_SYMBOL(tcf_queue_work);
210
211 /* Select new prio value from the range, managed by kernel. */
212
213 static inline u32 tcf_auto_prio(struct tcf_proto *tp)
214 {
215 u32 first = TC_H_MAKE(0xC0000000U, 0U);
216
217 if (tp)
218 first = tp->prio - 1;
219
220 return TC_H_MAJ(first);
221 }
222
223 static bool tcf_proto_check_kind(struct nlattr *kind, char *name)
224 {
225 if (kind)
226 return nla_strlcpy(name, kind, IFNAMSIZ) >= IFNAMSIZ;
227 memset(name, 0, IFNAMSIZ);
228 return false;
229 }
230
231 static bool tcf_proto_is_unlocked(const char *kind)
232 {
233 const struct tcf_proto_ops *ops;
234 bool ret;
235
236 if (strlen(kind) == 0)
237 return false;
238
239 ops = tcf_proto_lookup_ops(kind, false, NULL);
240 /* On error return false to take rtnl lock. Proto lookup/create
241 * functions will perform lookup again and properly handle errors.
242 */
243 if (IS_ERR(ops))
244 return false;
245
246 ret = !!(ops->flags & TCF_PROTO_OPS_DOIT_UNLOCKED);
247 module_put(ops->owner);
248 return ret;
249 }
250
251 static struct tcf_proto *tcf_proto_create(const char *kind, u32 protocol,
252 u32 prio, struct tcf_chain *chain,
253 bool rtnl_held,
254 struct netlink_ext_ack *extack)
255 {
256 struct tcf_proto *tp;
257 int err;
258
259 tp = kzalloc(sizeof(*tp), GFP_KERNEL);
260 if (!tp)
261 return ERR_PTR(-ENOBUFS);
262
263 tp->ops = tcf_proto_lookup_ops(kind, rtnl_held, extack);
264 if (IS_ERR(tp->ops)) {
265 err = PTR_ERR(tp->ops);
266 goto errout;
267 }
268 tp->classify = tp->ops->classify;
269 tp->protocol = protocol;
270 tp->prio = prio;
271 tp->chain = chain;
272 spin_lock_init(&tp->lock);
273 refcount_set(&tp->refcnt, 1);
274
275 err = tp->ops->init(tp);
276 if (err) {
277 module_put(tp->ops->owner);
278 goto errout;
279 }
280 return tp;
281
282 errout:
283 kfree(tp);
284 return ERR_PTR(err);
285 }
286
287 static void tcf_proto_get(struct tcf_proto *tp)
288 {
289 refcount_inc(&tp->refcnt);
290 }
291
292 static void tcf_chain_put(struct tcf_chain *chain);
293
294 static void tcf_proto_destroy(struct tcf_proto *tp, bool rtnl_held,
295 bool sig_destroy, struct netlink_ext_ack *extack)
296 {
297 tp->ops->destroy(tp, rtnl_held, extack);
298 if (sig_destroy)
299 tcf_proto_signal_destroyed(tp->chain, tp);
300 tcf_chain_put(tp->chain);
301 module_put(tp->ops->owner);
302 kfree_rcu(tp, rcu);
303 }
304
305 static void tcf_proto_put(struct tcf_proto *tp, bool rtnl_held,
306 struct netlink_ext_ack *extack)
307 {
308 if (refcount_dec_and_test(&tp->refcnt))
309 tcf_proto_destroy(tp, rtnl_held, true, extack);
310 }
311
312 static bool tcf_proto_check_delete(struct tcf_proto *tp)
313 {
314 if (tp->ops->delete_empty)
315 return tp->ops->delete_empty(tp);
316
317 tp->deleting = true;
318 return tp->deleting;
319 }
320
321 static void tcf_proto_mark_delete(struct tcf_proto *tp)
322 {
323 spin_lock(&tp->lock);
324 tp->deleting = true;
325 spin_unlock(&tp->lock);
326 }
327
328 static bool tcf_proto_is_deleting(struct tcf_proto *tp)
329 {
330 bool deleting;
331
332 spin_lock(&tp->lock);
333 deleting = tp->deleting;
334 spin_unlock(&tp->lock);
335
336 return deleting;
337 }
338
339 #define ASSERT_BLOCK_LOCKED(block) \
340 lockdep_assert_held(&(block)->lock)
341
342 struct tcf_filter_chain_list_item {
343 struct list_head list;
344 tcf_chain_head_change_t *chain_head_change;
345 void *chain_head_change_priv;
346 };
347
348 static struct tcf_chain *tcf_chain_create(struct tcf_block *block,
349 u32 chain_index)
350 {
351 struct tcf_chain *chain;
352
353 ASSERT_BLOCK_LOCKED(block);
354
355 chain = kzalloc(sizeof(*chain), GFP_KERNEL);
356 if (!chain)
357 return NULL;
358 list_add_tail_rcu(&chain->list, &block->chain_list);
359 mutex_init(&chain->filter_chain_lock);
360 chain->block = block;
361 chain->index = chain_index;
362 chain->refcnt = 1;
363 if (!chain->index)
364 block->chain0.chain = chain;
365 return chain;
366 }
367
368 static void tcf_chain_head_change_item(struct tcf_filter_chain_list_item *item,
369 struct tcf_proto *tp_head)
370 {
371 if (item->chain_head_change)
372 item->chain_head_change(tp_head, item->chain_head_change_priv);
373 }
374
375 static void tcf_chain0_head_change(struct tcf_chain *chain,
376 struct tcf_proto *tp_head)
377 {
378 struct tcf_filter_chain_list_item *item;
379 struct tcf_block *block = chain->block;
380
381 if (chain->index)
382 return;
383
384 mutex_lock(&block->lock);
385 list_for_each_entry(item, &block->chain0.filter_chain_list, list)
386 tcf_chain_head_change_item(item, tp_head);
387 mutex_unlock(&block->lock);
388 }
389
390 /* Returns true if block can be safely freed. */
391
392 static bool tcf_chain_detach(struct tcf_chain *chain)
393 {
394 struct tcf_block *block = chain->block;
395
396 ASSERT_BLOCK_LOCKED(block);
397
398 list_del_rcu(&chain->list);
399 if (!chain->index)
400 block->chain0.chain = NULL;
401
402 if (list_empty(&block->chain_list) &&
403 refcount_read(&block->refcnt) == 0)
404 return true;
405
406 return false;
407 }
408
409 static void tcf_block_destroy(struct tcf_block *block)
410 {
411 mutex_destroy(&block->lock);
412 mutex_destroy(&block->proto_destroy_lock);
413 kfree_rcu(block, rcu);
414 }
415
416 static void tcf_chain_destroy(struct tcf_chain *chain, bool free_block)
417 {
418 struct tcf_block *block = chain->block;
419
420 mutex_destroy(&chain->filter_chain_lock);
421 kfree_rcu(chain, rcu);
422 if (free_block)
423 tcf_block_destroy(block);
424 }
425
426 static void tcf_chain_hold(struct tcf_chain *chain)
427 {
428 ASSERT_BLOCK_LOCKED(chain->block);
429
430 ++chain->refcnt;
431 }
432
433 static bool tcf_chain_held_by_acts_only(struct tcf_chain *chain)
434 {
435 ASSERT_BLOCK_LOCKED(chain->block);
436
437 /* In case all the references are action references, this
438 * chain should not be shown to the user.
439 */
440 return chain->refcnt == chain->action_refcnt;
441 }
442
443 static struct tcf_chain *tcf_chain_lookup(struct tcf_block *block,
444 u32 chain_index)
445 {
446 struct tcf_chain *chain;
447
448 ASSERT_BLOCK_LOCKED(block);
449
450 list_for_each_entry(chain, &block->chain_list, list) {
451 if (chain->index == chain_index)
452 return chain;
453 }
454 return NULL;
455 }
456
457 #if IS_ENABLED(CONFIG_NET_TC_SKB_EXT)
458 static struct tcf_chain *tcf_chain_lookup_rcu(const struct tcf_block *block,
459 u32 chain_index)
460 {
461 struct tcf_chain *chain;
462
463 list_for_each_entry_rcu(chain, &block->chain_list, list) {
464 if (chain->index == chain_index)
465 return chain;
466 }
467 return NULL;
468 }
469 #endif
470
471 static int tc_chain_notify(struct tcf_chain *chain, struct sk_buff *oskb,
472 u32 seq, u16 flags, int event, bool unicast);
473
474 static struct tcf_chain *__tcf_chain_get(struct tcf_block *block,
475 u32 chain_index, bool create,
476 bool by_act)
477 {
478 struct tcf_chain *chain = NULL;
479 bool is_first_reference;
480
481 mutex_lock(&block->lock);
482 chain = tcf_chain_lookup(block, chain_index);
483 if (chain) {
484 tcf_chain_hold(chain);
485 } else {
486 if (!create)
487 goto errout;
488 chain = tcf_chain_create(block, chain_index);
489 if (!chain)
490 goto errout;
491 }
492
493 if (by_act)
494 ++chain->action_refcnt;
495 is_first_reference = chain->refcnt - chain->action_refcnt == 1;
496 mutex_unlock(&block->lock);
497
498 /* Send notification only in case we got the first
499 * non-action reference. Until then, the chain acts only as
500 * a placeholder for actions pointing to it and user ought
501 * not know about them.
502 */
503 if (is_first_reference && !by_act)
504 tc_chain_notify(chain, NULL, 0, NLM_F_CREATE | NLM_F_EXCL,
505 RTM_NEWCHAIN, false);
506
507 return chain;
508
509 errout:
510 mutex_unlock(&block->lock);
511 return chain;
512 }
513
514 static struct tcf_chain *tcf_chain_get(struct tcf_block *block, u32 chain_index,
515 bool create)
516 {
517 return __tcf_chain_get(block, chain_index, create, false);
518 }
519
520 struct tcf_chain *tcf_chain_get_by_act(struct tcf_block *block, u32 chain_index)
521 {
522 return __tcf_chain_get(block, chain_index, true, true);
523 }
524 EXPORT_SYMBOL(tcf_chain_get_by_act);
525
526 static void tc_chain_tmplt_del(const struct tcf_proto_ops *tmplt_ops,
527 void *tmplt_priv);
528 static int tc_chain_notify_delete(const struct tcf_proto_ops *tmplt_ops,
529 void *tmplt_priv, u32 chain_index,
530 struct tcf_block *block, struct sk_buff *oskb,
531 u32 seq, u16 flags, bool unicast);
532
533 static void __tcf_chain_put(struct tcf_chain *chain, bool by_act,
534 bool explicitly_created)
535 {
536 struct tcf_block *block = chain->block;
537 const struct tcf_proto_ops *tmplt_ops;
538 bool free_block = false;
539 unsigned int refcnt;
540 void *tmplt_priv;
541
542 mutex_lock(&block->lock);
543 if (explicitly_created) {
544 if (!chain->explicitly_created) {
545 mutex_unlock(&block->lock);
546 return;
547 }
548 chain->explicitly_created = false;
549 }
550
551 if (by_act)
552 chain->action_refcnt--;
553
554 /* tc_chain_notify_delete can't be called while holding block lock.
555 * However, when block is unlocked chain can be changed concurrently, so
556 * save these to temporary variables.
557 */
558 refcnt = --chain->refcnt;
559 tmplt_ops = chain->tmplt_ops;
560 tmplt_priv = chain->tmplt_priv;
561
562 /* The last dropped non-action reference will trigger notification. */
563 if (refcnt - chain->action_refcnt == 0 && !by_act) {
564 tc_chain_notify_delete(tmplt_ops, tmplt_priv, chain->index,
565 block, NULL, 0, 0, false);
566 /* Last reference to chain, no need to lock. */
567 chain->flushing = false;
568 }
569
570 if (refcnt == 0)
571 free_block = tcf_chain_detach(chain);
572 mutex_unlock(&block->lock);
573
574 if (refcnt == 0) {
575 tc_chain_tmplt_del(tmplt_ops, tmplt_priv);
576 tcf_chain_destroy(chain, free_block);
577 }
578 }
579
580 static void tcf_chain_put(struct tcf_chain *chain)
581 {
582 __tcf_chain_put(chain, false, false);
583 }
584
585 void tcf_chain_put_by_act(struct tcf_chain *chain)
586 {
587 __tcf_chain_put(chain, true, false);
588 }
589 EXPORT_SYMBOL(tcf_chain_put_by_act);
590
591 static void tcf_chain_put_explicitly_created(struct tcf_chain *chain)
592 {
593 __tcf_chain_put(chain, false, true);
594 }
595
596 static void tcf_chain_flush(struct tcf_chain *chain, bool rtnl_held)
597 {
598 struct tcf_proto *tp, *tp_next;
599
600 mutex_lock(&chain->filter_chain_lock);
601 tp = tcf_chain_dereference(chain->filter_chain, chain);
602 while (tp) {
603 tp_next = rcu_dereference_protected(tp->next, 1);
604 tcf_proto_signal_destroying(chain, tp);
605 tp = tp_next;
606 }
607 tp = tcf_chain_dereference(chain->filter_chain, chain);
608 RCU_INIT_POINTER(chain->filter_chain, NULL);
609 tcf_chain0_head_change(chain, NULL);
610 chain->flushing = true;
611 mutex_unlock(&chain->filter_chain_lock);
612
613 while (tp) {
614 tp_next = rcu_dereference_protected(tp->next, 1);
615 tcf_proto_put(tp, rtnl_held, NULL);
616 tp = tp_next;
617 }
618 }
619
620 static int tcf_block_setup(struct tcf_block *block,
621 struct flow_block_offload *bo);
622
623 static void tc_indr_block_cmd(struct net_device *dev, struct tcf_block *block,
624 flow_indr_block_bind_cb_t *cb, void *cb_priv,
625 enum flow_block_command command, bool ingress)
626 {
627 struct flow_block_offload bo = {
628 .command = command,
629 .binder_type = ingress ?
630 FLOW_BLOCK_BINDER_TYPE_CLSACT_INGRESS :
631 FLOW_BLOCK_BINDER_TYPE_CLSACT_EGRESS,
632 .net = dev_net(dev),
633 .block_shared = tcf_block_non_null_shared(block),
634 };
635 INIT_LIST_HEAD(&bo.cb_list);
636
637 if (!block)
638 return;
639
640 bo.block = &block->flow_block;
641
642 down_write(&block->cb_lock);
643 cb(dev, cb_priv, TC_SETUP_BLOCK, &bo);
644
645 tcf_block_setup(block, &bo);
646 up_write(&block->cb_lock);
647 }
648
649 static struct tcf_block *tc_dev_block(struct net_device *dev, bool ingress)
650 {
651 const struct Qdisc_class_ops *cops;
652 const struct Qdisc_ops *ops;
653 struct Qdisc *qdisc;
654
655 if (!dev_ingress_queue(dev))
656 return NULL;
657
658 qdisc = dev_ingress_queue(dev)->qdisc_sleeping;
659 if (!qdisc)
660 return NULL;
661
662 ops = qdisc->ops;
663 if (!ops)
664 return NULL;
665
666 if (!ingress && !strcmp("ingress", ops->id))
667 return NULL;
668
669 cops = ops->cl_ops;
670 if (!cops)
671 return NULL;
672
673 if (!cops->tcf_block)
674 return NULL;
675
676 return cops->tcf_block(qdisc,
677 ingress ? TC_H_MIN_INGRESS : TC_H_MIN_EGRESS,
678 NULL);
679 }
680
681 static void tc_indr_block_get_and_cmd(struct net_device *dev,
682 flow_indr_block_bind_cb_t *cb,
683 void *cb_priv,
684 enum flow_block_command command)
685 {
686 struct tcf_block *block;
687
688 block = tc_dev_block(dev, true);
689 tc_indr_block_cmd(dev, block, cb, cb_priv, command, true);
690
691 block = tc_dev_block(dev, false);
692 tc_indr_block_cmd(dev, block, cb, cb_priv, command, false);
693 }
694
695 static void tc_indr_block_call(struct tcf_block *block,
696 struct net_device *dev,
697 struct tcf_block_ext_info *ei,
698 enum flow_block_command command,
699 struct netlink_ext_ack *extack)
700 {
701 struct flow_block_offload bo = {
702 .command = command,
703 .binder_type = ei->binder_type,
704 .net = dev_net(dev),
705 .block = &block->flow_block,
706 .block_shared = tcf_block_shared(block),
707 .extack = extack,
708 };
709 INIT_LIST_HEAD(&bo.cb_list);
710
711 flow_indr_block_call(dev, &bo, command, TC_SETUP_BLOCK);
712 tcf_block_setup(block, &bo);
713 }
714
715 static bool tcf_block_offload_in_use(struct tcf_block *block)
716 {
717 return atomic_read(&block->offloadcnt);
718 }
719
720 static int tcf_block_offload_cmd(struct tcf_block *block,
721 struct net_device *dev,
722 struct tcf_block_ext_info *ei,
723 enum flow_block_command command,
724 struct netlink_ext_ack *extack)
725 {
726 struct flow_block_offload bo = {};
727 int err;
728
729 bo.net = dev_net(dev);
730 bo.command = command;
731 bo.binder_type = ei->binder_type;
732 bo.block = &block->flow_block;
733 bo.block_shared = tcf_block_shared(block);
734 bo.extack = extack;
735 INIT_LIST_HEAD(&bo.cb_list);
736
737 err = dev->netdev_ops->ndo_setup_tc(dev, TC_SETUP_BLOCK, &bo);
738 if (err < 0)
739 return err;
740
741 return tcf_block_setup(block, &bo);
742 }
743
744 static int tcf_block_offload_bind(struct tcf_block *block, struct Qdisc *q,
745 struct tcf_block_ext_info *ei,
746 struct netlink_ext_ack *extack)
747 {
748 struct net_device *dev = q->dev_queue->dev;
749 int err;
750
751 down_write(&block->cb_lock);
752 if (!dev->netdev_ops->ndo_setup_tc)
753 goto no_offload_dev_inc;
754
755 /* If tc offload feature is disabled and the block we try to bind
756 * to already has some offloaded filters, forbid to bind.
757 */
758 if (!tc_can_offload(dev) && tcf_block_offload_in_use(block)) {
759 NL_SET_ERR_MSG(extack, "Bind to offloaded block failed as dev has offload disabled");
760 err = -EOPNOTSUPP;
761 goto err_unlock;
762 }
763
764 err = tcf_block_offload_cmd(block, dev, ei, FLOW_BLOCK_BIND, extack);
765 if (err == -EOPNOTSUPP)
766 goto no_offload_dev_inc;
767 if (err)
768 goto err_unlock;
769
770 tc_indr_block_call(block, dev, ei, FLOW_BLOCK_BIND, extack);
771 up_write(&block->cb_lock);
772 return 0;
773
774 no_offload_dev_inc:
775 if (tcf_block_offload_in_use(block)) {
776 err = -EOPNOTSUPP;
777 goto err_unlock;
778 }
779 err = 0;
780 block->nooffloaddevcnt++;
781 tc_indr_block_call(block, dev, ei, FLOW_BLOCK_BIND, extack);
782 err_unlock:
783 up_write(&block->cb_lock);
784 return err;
785 }
786
787 static void tcf_block_offload_unbind(struct tcf_block *block, struct Qdisc *q,
788 struct tcf_block_ext_info *ei)
789 {
790 struct net_device *dev = q->dev_queue->dev;
791 int err;
792
793 down_write(&block->cb_lock);
794 tc_indr_block_call(block, dev, ei, FLOW_BLOCK_UNBIND, NULL);
795
796 if (!dev->netdev_ops->ndo_setup_tc)
797 goto no_offload_dev_dec;
798 err = tcf_block_offload_cmd(block, dev, ei, FLOW_BLOCK_UNBIND, NULL);
799 if (err == -EOPNOTSUPP)
800 goto no_offload_dev_dec;
801 up_write(&block->cb_lock);
802 return;
803
804 no_offload_dev_dec:
805 WARN_ON(block->nooffloaddevcnt-- == 0);
806 up_write(&block->cb_lock);
807 }
808
809 static int
810 tcf_chain0_head_change_cb_add(struct tcf_block *block,
811 struct tcf_block_ext_info *ei,
812 struct netlink_ext_ack *extack)
813 {
814 struct tcf_filter_chain_list_item *item;
815 struct tcf_chain *chain0;
816
817 item = kmalloc(sizeof(*item), GFP_KERNEL);
818 if (!item) {
819 NL_SET_ERR_MSG(extack, "Memory allocation for head change callback item failed");
820 return -ENOMEM;
821 }
822 item->chain_head_change = ei->chain_head_change;
823 item->chain_head_change_priv = ei->chain_head_change_priv;
824
825 mutex_lock(&block->lock);
826 chain0 = block->chain0.chain;
827 if (chain0)
828 tcf_chain_hold(chain0);
829 else
830 list_add(&item->list, &block->chain0.filter_chain_list);
831 mutex_unlock(&block->lock);
832
833 if (chain0) {
834 struct tcf_proto *tp_head;
835
836 mutex_lock(&chain0->filter_chain_lock);
837
838 tp_head = tcf_chain_dereference(chain0->filter_chain, chain0);
839 if (tp_head)
840 tcf_chain_head_change_item(item, tp_head);
841
842 mutex_lock(&block->lock);
843 list_add(&item->list, &block->chain0.filter_chain_list);
844 mutex_unlock(&block->lock);
845
846 mutex_unlock(&chain0->filter_chain_lock);
847 tcf_chain_put(chain0);
848 }
849
850 return 0;
851 }
852
853 static void
854 tcf_chain0_head_change_cb_del(struct tcf_block *block,
855 struct tcf_block_ext_info *ei)
856 {
857 struct tcf_filter_chain_list_item *item;
858
859 mutex_lock(&block->lock);
860 list_for_each_entry(item, &block->chain0.filter_chain_list, list) {
861 if ((!ei->chain_head_change && !ei->chain_head_change_priv) ||
862 (item->chain_head_change == ei->chain_head_change &&
863 item->chain_head_change_priv == ei->chain_head_change_priv)) {
864 if (block->chain0.chain)
865 tcf_chain_head_change_item(item, NULL);
866 list_del(&item->list);
867 mutex_unlock(&block->lock);
868
869 kfree(item);
870 return;
871 }
872 }
873 mutex_unlock(&block->lock);
874 WARN_ON(1);
875 }
876
877 struct tcf_net {
878 spinlock_t idr_lock; /* Protects idr */
879 struct idr idr;
880 };
881
882 static unsigned int tcf_net_id;
883
884 static int tcf_block_insert(struct tcf_block *block, struct net *net,
885 struct netlink_ext_ack *extack)
886 {
887 struct tcf_net *tn = net_generic(net, tcf_net_id);
888 int err;
889
890 idr_preload(GFP_KERNEL);
891 spin_lock(&tn->idr_lock);
892 err = idr_alloc_u32(&tn->idr, block, &block->index, block->index,
893 GFP_NOWAIT);
894 spin_unlock(&tn->idr_lock);
895 idr_preload_end();
896
897 return err;
898 }
899
900 static void tcf_block_remove(struct tcf_block *block, struct net *net)
901 {
902 struct tcf_net *tn = net_generic(net, tcf_net_id);
903
904 spin_lock(&tn->idr_lock);
905 idr_remove(&tn->idr, block->index);
906 spin_unlock(&tn->idr_lock);
907 }
908
909 static struct tcf_block *tcf_block_create(struct net *net, struct Qdisc *q,
910 u32 block_index,
911 struct netlink_ext_ack *extack)
912 {
913 struct tcf_block *block;
914
915 block = kzalloc(sizeof(*block), GFP_KERNEL);
916 if (!block) {
917 NL_SET_ERR_MSG(extack, "Memory allocation for block failed");
918 return ERR_PTR(-ENOMEM);
919 }
920 mutex_init(&block->lock);
921 mutex_init(&block->proto_destroy_lock);
922 init_rwsem(&block->cb_lock);
923 flow_block_init(&block->flow_block);
924 INIT_LIST_HEAD(&block->chain_list);
925 INIT_LIST_HEAD(&block->owner_list);
926 INIT_LIST_HEAD(&block->chain0.filter_chain_list);
927
928 refcount_set(&block->refcnt, 1);
929 block->net = net;
930 block->index = block_index;
931
932 /* Don't store q pointer for blocks which are shared */
933 if (!tcf_block_shared(block))
934 block->q = q;
935 return block;
936 }
937
938 static struct tcf_block *tcf_block_lookup(struct net *net, u32 block_index)
939 {
940 struct tcf_net *tn = net_generic(net, tcf_net_id);
941
942 return idr_find(&tn->idr, block_index);
943 }
944
945 static struct tcf_block *tcf_block_refcnt_get(struct net *net, u32 block_index)
946 {
947 struct tcf_block *block;
948
949 rcu_read_lock();
950 block = tcf_block_lookup(net, block_index);
951 if (block && !refcount_inc_not_zero(&block->refcnt))
952 block = NULL;
953 rcu_read_unlock();
954
955 return block;
956 }
957
958 static struct tcf_chain *
959 __tcf_get_next_chain(struct tcf_block *block, struct tcf_chain *chain)
960 {
961 mutex_lock(&block->lock);
962 if (chain)
963 chain = list_is_last(&chain->list, &block->chain_list) ?
964 NULL : list_next_entry(chain, list);
965 else
966 chain = list_first_entry_or_null(&block->chain_list,
967 struct tcf_chain, list);
968
969 /* skip all action-only chains */
970 while (chain && tcf_chain_held_by_acts_only(chain))
971 chain = list_is_last(&chain->list, &block->chain_list) ?
972 NULL : list_next_entry(chain, list);
973
974 if (chain)
975 tcf_chain_hold(chain);
976 mutex_unlock(&block->lock);
977
978 return chain;
979 }
980
981 /* Function to be used by all clients that want to iterate over all chains on
982 * block. It properly obtains block->lock and takes reference to chain before
983 * returning it. Users of this function must be tolerant to concurrent chain
984 * insertion/deletion or ensure that no concurrent chain modification is
985 * possible. Note that all netlink dump callbacks cannot guarantee to provide
986 * consistent dump because rtnl lock is released each time skb is filled with
987 * data and sent to user-space.
988 */
989
990 struct tcf_chain *
991 tcf_get_next_chain(struct tcf_block *block, struct tcf_chain *chain)
992 {
993 struct tcf_chain *chain_next = __tcf_get_next_chain(block, chain);
994
995 if (chain)
996 tcf_chain_put(chain);
997
998 return chain_next;
999 }
1000 EXPORT_SYMBOL(tcf_get_next_chain);
1001
1002 static struct tcf_proto *
1003 __tcf_get_next_proto(struct tcf_chain *chain, struct tcf_proto *tp)
1004 {
1005 u32 prio = 0;
1006
1007 ASSERT_RTNL();
1008 mutex_lock(&chain->filter_chain_lock);
1009
1010 if (!tp) {
1011 tp = tcf_chain_dereference(chain->filter_chain, chain);
1012 } else if (tcf_proto_is_deleting(tp)) {
1013 /* 'deleting' flag is set and chain->filter_chain_lock was
1014 * unlocked, which means next pointer could be invalid. Restart
1015 * search.
1016 */
1017 prio = tp->prio + 1;
1018 tp = tcf_chain_dereference(chain->filter_chain, chain);
1019
1020 for (; tp; tp = tcf_chain_dereference(tp->next, chain))
1021 if (!tp->deleting && tp->prio >= prio)
1022 break;
1023 } else {
1024 tp = tcf_chain_dereference(tp->next, chain);
1025 }
1026
1027 if (tp)
1028 tcf_proto_get(tp);
1029
1030 mutex_unlock(&chain->filter_chain_lock);
1031
1032 return tp;
1033 }
1034
1035 /* Function to be used by all clients that want to iterate over all tp's on
1036 * chain. Users of this function must be tolerant to concurrent tp
1037 * insertion/deletion or ensure that no concurrent chain modification is
1038 * possible. Note that all netlink dump callbacks cannot guarantee to provide
1039 * consistent dump because rtnl lock is released each time skb is filled with
1040 * data and sent to user-space.
1041 */
1042
1043 struct tcf_proto *
1044 tcf_get_next_proto(struct tcf_chain *chain, struct tcf_proto *tp,
1045 bool rtnl_held)
1046 {
1047 struct tcf_proto *tp_next = __tcf_get_next_proto(chain, tp);
1048
1049 if (tp)
1050 tcf_proto_put(tp, rtnl_held, NULL);
1051
1052 return tp_next;
1053 }
1054 EXPORT_SYMBOL(tcf_get_next_proto);
1055
1056 static void tcf_block_flush_all_chains(struct tcf_block *block, bool rtnl_held)
1057 {
1058 struct tcf_chain *chain;
1059
1060 /* Last reference to block. At this point chains cannot be added or
1061 * removed concurrently.
1062 */
1063 for (chain = tcf_get_next_chain(block, NULL);
1064 chain;
1065 chain = tcf_get_next_chain(block, chain)) {
1066 tcf_chain_put_explicitly_created(chain);
1067 tcf_chain_flush(chain, rtnl_held);
1068 }
1069 }
1070
1071 /* Lookup Qdisc and increments its reference counter.
1072 * Set parent, if necessary.
1073 */
1074
1075 static int __tcf_qdisc_find(struct net *net, struct Qdisc **q,
1076 u32 *parent, int ifindex, bool rtnl_held,
1077 struct netlink_ext_ack *extack)
1078 {
1079 const struct Qdisc_class_ops *cops;
1080 struct net_device *dev;
1081 int err = 0;
1082
1083 if (ifindex == TCM_IFINDEX_MAGIC_BLOCK)
1084 return 0;
1085
1086 rcu_read_lock();
1087
1088 /* Find link */
1089 dev = dev_get_by_index_rcu(net, ifindex);
1090 if (!dev) {
1091 rcu_read_unlock();
1092 return -ENODEV;
1093 }
1094
1095 /* Find qdisc */
1096 if (!*parent) {
1097 *q = dev->qdisc;
1098 *parent = (*q)->handle;
1099 } else {
1100 *q = qdisc_lookup_rcu(dev, TC_H_MAJ(*parent));
1101 if (!*q) {
1102 NL_SET_ERR_MSG(extack, "Parent Qdisc doesn't exists");
1103 err = -EINVAL;
1104 goto errout_rcu;
1105 }
1106 }
1107
1108 *q = qdisc_refcount_inc_nz(*q);
1109 if (!*q) {
1110 NL_SET_ERR_MSG(extack, "Parent Qdisc doesn't exists");
1111 err = -EINVAL;
1112 goto errout_rcu;
1113 }
1114
1115 /* Is it classful? */
1116 cops = (*q)->ops->cl_ops;
1117 if (!cops) {
1118 NL_SET_ERR_MSG(extack, "Qdisc not classful");
1119 err = -EINVAL;
1120 goto errout_qdisc;
1121 }
1122
1123 if (!cops->tcf_block) {
1124 NL_SET_ERR_MSG(extack, "Class doesn't support blocks");
1125 err = -EOPNOTSUPP;
1126 goto errout_qdisc;
1127 }
1128
1129 errout_rcu:
1130 /* At this point we know that qdisc is not noop_qdisc,
1131 * which means that qdisc holds a reference to net_device
1132 * and we hold a reference to qdisc, so it is safe to release
1133 * rcu read lock.
1134 */
1135 rcu_read_unlock();
1136 return err;
1137
1138 errout_qdisc:
1139 rcu_read_unlock();
1140
1141 if (rtnl_held)
1142 qdisc_put(*q);
1143 else
1144 qdisc_put_unlocked(*q);
1145 *q = NULL;
1146
1147 return err;
1148 }
1149
1150 static int __tcf_qdisc_cl_find(struct Qdisc *q, u32 parent, unsigned long *cl,
1151 int ifindex, struct netlink_ext_ack *extack)
1152 {
1153 if (ifindex == TCM_IFINDEX_MAGIC_BLOCK)
1154 return 0;
1155
1156 /* Do we search for filter, attached to class? */
1157 if (TC_H_MIN(parent)) {
1158 const struct Qdisc_class_ops *cops = q->ops->cl_ops;
1159
1160 *cl = cops->find(q, parent);
1161 if (*cl == 0) {
1162 NL_SET_ERR_MSG(extack, "Specified class doesn't exist");
1163 return -ENOENT;
1164 }
1165 }
1166
1167 return 0;
1168 }
1169
1170 static struct tcf_block *__tcf_block_find(struct net *net, struct Qdisc *q,
1171 unsigned long cl, int ifindex,
1172 u32 block_index,
1173 struct netlink_ext_ack *extack)
1174 {
1175 struct tcf_block *block;
1176
1177 if (ifindex == TCM_IFINDEX_MAGIC_BLOCK) {
1178 block = tcf_block_refcnt_get(net, block_index);
1179 if (!block) {
1180 NL_SET_ERR_MSG(extack, "Block of given index was not found");
1181 return ERR_PTR(-EINVAL);
1182 }
1183 } else {
1184 const struct Qdisc_class_ops *cops = q->ops->cl_ops;
1185
1186 block = cops->tcf_block(q, cl, extack);
1187 if (!block)
1188 return ERR_PTR(-EINVAL);
1189
1190 if (tcf_block_shared(block)) {
1191 NL_SET_ERR_MSG(extack, "This filter block is shared. Please use the block index to manipulate the filters");
1192 return ERR_PTR(-EOPNOTSUPP);
1193 }
1194
1195 /* Always take reference to block in order to support execution
1196 * of rules update path of cls API without rtnl lock. Caller
1197 * must release block when it is finished using it. 'if' block
1198 * of this conditional obtain reference to block by calling
1199 * tcf_block_refcnt_get().
1200 */
1201 refcount_inc(&block->refcnt);
1202 }
1203
1204 return block;
1205 }
1206
1207 static void __tcf_block_put(struct tcf_block *block, struct Qdisc *q,
1208 struct tcf_block_ext_info *ei, bool rtnl_held)
1209 {
1210 if (refcount_dec_and_mutex_lock(&block->refcnt, &block->lock)) {
1211 /* Flushing/putting all chains will cause the block to be
1212 * deallocated when last chain is freed. However, if chain_list
1213 * is empty, block has to be manually deallocated. After block
1214 * reference counter reached 0, it is no longer possible to
1215 * increment it or add new chains to block.
1216 */
1217 bool free_block = list_empty(&block->chain_list);
1218
1219 mutex_unlock(&block->lock);
1220 if (tcf_block_shared(block))
1221 tcf_block_remove(block, block->net);
1222
1223 if (q)
1224 tcf_block_offload_unbind(block, q, ei);
1225
1226 if (free_block)
1227 tcf_block_destroy(block);
1228 else
1229 tcf_block_flush_all_chains(block, rtnl_held);
1230 } else if (q) {
1231 tcf_block_offload_unbind(block, q, ei);
1232 }
1233 }
1234
1235 static void tcf_block_refcnt_put(struct tcf_block *block, bool rtnl_held)
1236 {
1237 __tcf_block_put(block, NULL, NULL, rtnl_held);
1238 }
1239
1240 /* Find tcf block.
1241 * Set q, parent, cl when appropriate.
1242 */
1243
1244 static struct tcf_block *tcf_block_find(struct net *net, struct Qdisc **q,
1245 u32 *parent, unsigned long *cl,
1246 int ifindex, u32 block_index,
1247 struct netlink_ext_ack *extack)
1248 {
1249 struct tcf_block *block;
1250 int err = 0;
1251
1252 ASSERT_RTNL();
1253
1254 err = __tcf_qdisc_find(net, q, parent, ifindex, true, extack);
1255 if (err)
1256 goto errout;
1257
1258 err = __tcf_qdisc_cl_find(*q, *parent, cl, ifindex, extack);
1259 if (err)
1260 goto errout_qdisc;
1261
1262 block = __tcf_block_find(net, *q, *cl, ifindex, block_index, extack);
1263 if (IS_ERR(block)) {
1264 err = PTR_ERR(block);
1265 goto errout_qdisc;
1266 }
1267
1268 return block;
1269
1270 errout_qdisc:
1271 if (*q)
1272 qdisc_put(*q);
1273 errout:
1274 *q = NULL;
1275 return ERR_PTR(err);
1276 }
1277
1278 static void tcf_block_release(struct Qdisc *q, struct tcf_block *block,
1279 bool rtnl_held)
1280 {
1281 if (!IS_ERR_OR_NULL(block))
1282 tcf_block_refcnt_put(block, rtnl_held);
1283
1284 if (q) {
1285 if (rtnl_held)
1286 qdisc_put(q);
1287 else
1288 qdisc_put_unlocked(q);
1289 }
1290 }
1291
1292 struct tcf_block_owner_item {
1293 struct list_head list;
1294 struct Qdisc *q;
1295 enum flow_block_binder_type binder_type;
1296 };
1297
1298 static void
1299 tcf_block_owner_netif_keep_dst(struct tcf_block *block,
1300 struct Qdisc *q,
1301 enum flow_block_binder_type binder_type)
1302 {
1303 if (block->keep_dst &&
1304 binder_type != FLOW_BLOCK_BINDER_TYPE_CLSACT_INGRESS &&
1305 binder_type != FLOW_BLOCK_BINDER_TYPE_CLSACT_EGRESS)
1306 netif_keep_dst(qdisc_dev(q));
1307 }
1308
1309 void tcf_block_netif_keep_dst(struct tcf_block *block)
1310 {
1311 struct tcf_block_owner_item *item;
1312
1313 block->keep_dst = true;
1314 list_for_each_entry(item, &block->owner_list, list)
1315 tcf_block_owner_netif_keep_dst(block, item->q,
1316 item->binder_type);
1317 }
1318 EXPORT_SYMBOL(tcf_block_netif_keep_dst);
1319
1320 static int tcf_block_owner_add(struct tcf_block *block,
1321 struct Qdisc *q,
1322 enum flow_block_binder_type binder_type)
1323 {
1324 struct tcf_block_owner_item *item;
1325
1326 item = kmalloc(sizeof(*item), GFP_KERNEL);
1327 if (!item)
1328 return -ENOMEM;
1329 item->q = q;
1330 item->binder_type = binder_type;
1331 list_add(&item->list, &block->owner_list);
1332 return 0;
1333 }
1334
1335 static void tcf_block_owner_del(struct tcf_block *block,
1336 struct Qdisc *q,
1337 enum flow_block_binder_type binder_type)
1338 {
1339 struct tcf_block_owner_item *item;
1340
1341 list_for_each_entry(item, &block->owner_list, list) {
1342 if (item->q == q && item->binder_type == binder_type) {
1343 list_del(&item->list);
1344 kfree(item);
1345 return;
1346 }
1347 }
1348 WARN_ON(1);
1349 }
1350
1351 int tcf_block_get_ext(struct tcf_block **p_block, struct Qdisc *q,
1352 struct tcf_block_ext_info *ei,
1353 struct netlink_ext_ack *extack)
1354 {
1355 struct net *net = qdisc_net(q);
1356 struct tcf_block *block = NULL;
1357 int err;
1358
1359 if (ei->block_index)
1360 /* block_index not 0 means the shared block is requested */
1361 block = tcf_block_refcnt_get(net, ei->block_index);
1362
1363 if (!block) {
1364 block = tcf_block_create(net, q, ei->block_index, extack);
1365 if (IS_ERR(block))
1366 return PTR_ERR(block);
1367 if (tcf_block_shared(block)) {
1368 err = tcf_block_insert(block, net, extack);
1369 if (err)
1370 goto err_block_insert;
1371 }
1372 }
1373
1374 err = tcf_block_owner_add(block, q, ei->binder_type);
1375 if (err)
1376 goto err_block_owner_add;
1377
1378 tcf_block_owner_netif_keep_dst(block, q, ei->binder_type);
1379
1380 err = tcf_chain0_head_change_cb_add(block, ei, extack);
1381 if (err)
1382 goto err_chain0_head_change_cb_add;
1383
1384 err = tcf_block_offload_bind(block, q, ei, extack);
1385 if (err)
1386 goto err_block_offload_bind;
1387
1388 *p_block = block;
1389 return 0;
1390
1391 err_block_offload_bind:
1392 tcf_chain0_head_change_cb_del(block, ei);
1393 err_chain0_head_change_cb_add:
1394 tcf_block_owner_del(block, q, ei->binder_type);
1395 err_block_owner_add:
1396 err_block_insert:
1397 tcf_block_refcnt_put(block, true);
1398 return err;
1399 }
1400 EXPORT_SYMBOL(tcf_block_get_ext);
1401
1402 static void tcf_chain_head_change_dflt(struct tcf_proto *tp_head, void *priv)
1403 {
1404 struct tcf_proto __rcu **p_filter_chain = priv;
1405
1406 rcu_assign_pointer(*p_filter_chain, tp_head);
1407 }
1408
1409 int tcf_block_get(struct tcf_block **p_block,
1410 struct tcf_proto __rcu **p_filter_chain, struct Qdisc *q,
1411 struct netlink_ext_ack *extack)
1412 {
1413 struct tcf_block_ext_info ei = {
1414 .chain_head_change = tcf_chain_head_change_dflt,
1415 .chain_head_change_priv = p_filter_chain,
1416 };
1417
1418 WARN_ON(!p_filter_chain);
1419 return tcf_block_get_ext(p_block, q, &ei, extack);
1420 }
1421 EXPORT_SYMBOL(tcf_block_get);
1422
1423 /* XXX: Standalone actions are not allowed to jump to any chain, and bound
1424 * actions should be all removed after flushing.
1425 */
1426 void tcf_block_put_ext(struct tcf_block *block, struct Qdisc *q,
1427 struct tcf_block_ext_info *ei)
1428 {
1429 if (!block)
1430 return;
1431 tcf_chain0_head_change_cb_del(block, ei);
1432 tcf_block_owner_del(block, q, ei->binder_type);
1433
1434 __tcf_block_put(block, q, ei, true);
1435 }
1436 EXPORT_SYMBOL(tcf_block_put_ext);
1437
1438 void tcf_block_put(struct tcf_block *block)
1439 {
1440 struct tcf_block_ext_info ei = {0, };
1441
1442 if (!block)
1443 return;
1444 tcf_block_put_ext(block, block->q, &ei);
1445 }
1446
1447 EXPORT_SYMBOL(tcf_block_put);
1448
1449 static int
1450 tcf_block_playback_offloads(struct tcf_block *block, flow_setup_cb_t *cb,
1451 void *cb_priv, bool add, bool offload_in_use,
1452 struct netlink_ext_ack *extack)
1453 {
1454 struct tcf_chain *chain, *chain_prev;
1455 struct tcf_proto *tp, *tp_prev;
1456 int err;
1457
1458 lockdep_assert_held(&block->cb_lock);
1459
1460 for (chain = __tcf_get_next_chain(block, NULL);
1461 chain;
1462 chain_prev = chain,
1463 chain = __tcf_get_next_chain(block, chain),
1464 tcf_chain_put(chain_prev)) {
1465 for (tp = __tcf_get_next_proto(chain, NULL); tp;
1466 tp_prev = tp,
1467 tp = __tcf_get_next_proto(chain, tp),
1468 tcf_proto_put(tp_prev, true, NULL)) {
1469 if (tp->ops->reoffload) {
1470 err = tp->ops->reoffload(tp, add, cb, cb_priv,
1471 extack);
1472 if (err && add)
1473 goto err_playback_remove;
1474 } else if (add && offload_in_use) {
1475 err = -EOPNOTSUPP;
1476 NL_SET_ERR_MSG(extack, "Filter HW offload failed - classifier without re-offloading support");
1477 goto err_playback_remove;
1478 }
1479 }
1480 }
1481
1482 return 0;
1483
1484 err_playback_remove:
1485 tcf_proto_put(tp, true, NULL);
1486 tcf_chain_put(chain);
1487 tcf_block_playback_offloads(block, cb, cb_priv, false, offload_in_use,
1488 extack);
1489 return err;
1490 }
1491
1492 static int tcf_block_bind(struct tcf_block *block,
1493 struct flow_block_offload *bo)
1494 {
1495 struct flow_block_cb *block_cb, *next;
1496 int err, i = 0;
1497
1498 lockdep_assert_held(&block->cb_lock);
1499
1500 list_for_each_entry(block_cb, &bo->cb_list, list) {
1501 err = tcf_block_playback_offloads(block, block_cb->cb,
1502 block_cb->cb_priv, true,
1503 tcf_block_offload_in_use(block),
1504 bo->extack);
1505 if (err)
1506 goto err_unroll;
1507 if (!bo->unlocked_driver_cb)
1508 block->lockeddevcnt++;
1509
1510 i++;
1511 }
1512 list_splice(&bo->cb_list, &block->flow_block.cb_list);
1513
1514 return 0;
1515
1516 err_unroll:
1517 list_for_each_entry_safe(block_cb, next, &bo->cb_list, list) {
1518 if (i-- > 0) {
1519 list_del(&block_cb->list);
1520 tcf_block_playback_offloads(block, block_cb->cb,
1521 block_cb->cb_priv, false,
1522 tcf_block_offload_in_use(block),
1523 NULL);
1524 if (!bo->unlocked_driver_cb)
1525 block->lockeddevcnt--;
1526 }
1527 flow_block_cb_free(block_cb);
1528 }
1529
1530 return err;
1531 }
1532
1533 static void tcf_block_unbind(struct tcf_block *block,
1534 struct flow_block_offload *bo)
1535 {
1536 struct flow_block_cb *block_cb, *next;
1537
1538 lockdep_assert_held(&block->cb_lock);
1539
1540 list_for_each_entry_safe(block_cb, next, &bo->cb_list, list) {
1541 tcf_block_playback_offloads(block, block_cb->cb,
1542 block_cb->cb_priv, false,
1543 tcf_block_offload_in_use(block),
1544 NULL);
1545 list_del(&block_cb->list);
1546 flow_block_cb_free(block_cb);
1547 if (!bo->unlocked_driver_cb)
1548 block->lockeddevcnt--;
1549 }
1550 }
1551
1552 static int tcf_block_setup(struct tcf_block *block,
1553 struct flow_block_offload *bo)
1554 {
1555 int err;
1556
1557 switch (bo->command) {
1558 case FLOW_BLOCK_BIND:
1559 err = tcf_block_bind(block, bo);
1560 break;
1561 case FLOW_BLOCK_UNBIND:
1562 err = 0;
1563 tcf_block_unbind(block, bo);
1564 break;
1565 default:
1566 WARN_ON_ONCE(1);
1567 err = -EOPNOTSUPP;
1568 }
1569
1570 return err;
1571 }
1572
1573 /* Main classifier routine: scans classifier chain attached
1574 * to this qdisc, (optionally) tests for protocol and asks
1575 * specific classifiers.
1576 */
1577 static inline int __tcf_classify(struct sk_buff *skb,
1578 const struct tcf_proto *tp,
1579 const struct tcf_proto *orig_tp,
1580 struct tcf_result *res,
1581 bool compat_mode,
1582 u32 *last_executed_chain)
1583 {
1584 #ifdef CONFIG_NET_CLS_ACT
1585 const int max_reclassify_loop = 4;
1586 const struct tcf_proto *first_tp;
1587 int limit = 0;
1588
1589 reclassify:
1590 #endif
1591 for (; tp; tp = rcu_dereference_bh(tp->next)) {
1592 __be16 protocol = tc_skb_protocol(skb);
1593 int err;
1594
1595 if (tp->protocol != protocol &&
1596 tp->protocol != htons(ETH_P_ALL))
1597 continue;
1598
1599 err = tp->classify(skb, tp, res);
1600 #ifdef CONFIG_NET_CLS_ACT
1601 if (unlikely(err == TC_ACT_RECLASSIFY && !compat_mode)) {
1602 first_tp = orig_tp;
1603 *last_executed_chain = first_tp->chain->index;
1604 goto reset;
1605 } else if (unlikely(TC_ACT_EXT_CMP(err, TC_ACT_GOTO_CHAIN))) {
1606 first_tp = res->goto_tp;
1607 *last_executed_chain = err & TC_ACT_EXT_VAL_MASK;
1608 goto reset;
1609 }
1610 #endif
1611 if (err >= 0)
1612 return err;
1613 }
1614
1615 return TC_ACT_UNSPEC; /* signal: continue lookup */
1616 #ifdef CONFIG_NET_CLS_ACT
1617 reset:
1618 if (unlikely(limit++ >= max_reclassify_loop)) {
1619 net_notice_ratelimited("%u: reclassify loop, rule prio %u, protocol %02x\n",
1620 tp->chain->block->index,
1621 tp->prio & 0xffff,
1622 ntohs(tp->protocol));
1623 return TC_ACT_SHOT;
1624 }
1625
1626 tp = first_tp;
1627 goto reclassify;
1628 #endif
1629 }
1630
1631 int tcf_classify(struct sk_buff *skb, const struct tcf_proto *tp,
1632 struct tcf_result *res, bool compat_mode)
1633 {
1634 u32 last_executed_chain = 0;
1635
1636 return __tcf_classify(skb, tp, tp, res, compat_mode,
1637 &last_executed_chain);
1638 }
1639 EXPORT_SYMBOL(tcf_classify);
1640
1641 int tcf_classify_ingress(struct sk_buff *skb,
1642 const struct tcf_block *ingress_block,
1643 const struct tcf_proto *tp,
1644 struct tcf_result *res, bool compat_mode)
1645 {
1646 #if !IS_ENABLED(CONFIG_NET_TC_SKB_EXT)
1647 u32 last_executed_chain = 0;
1648
1649 return __tcf_classify(skb, tp, tp, res, compat_mode,
1650 &last_executed_chain);
1651 #else
1652 u32 last_executed_chain = tp ? tp->chain->index : 0;
1653 const struct tcf_proto *orig_tp = tp;
1654 struct tc_skb_ext *ext;
1655 int ret;
1656
1657 ext = skb_ext_find(skb, TC_SKB_EXT);
1658
1659 if (ext && ext->chain) {
1660 struct tcf_chain *fchain;
1661
1662 fchain = tcf_chain_lookup_rcu(ingress_block, ext->chain);
1663 if (!fchain)
1664 return TC_ACT_SHOT;
1665
1666 /* Consume, so cloned/redirect skbs won't inherit ext */
1667 skb_ext_del(skb, TC_SKB_EXT);
1668
1669 tp = rcu_dereference_bh(fchain->filter_chain);
1670 last_executed_chain = fchain->index;
1671 }
1672
1673 ret = __tcf_classify(skb, tp, orig_tp, res, compat_mode,
1674 &last_executed_chain);
1675
1676 /* If we missed on some chain */
1677 if (ret == TC_ACT_UNSPEC && last_executed_chain) {
1678 ext = skb_ext_add(skb, TC_SKB_EXT);
1679 if (WARN_ON_ONCE(!ext))
1680 return TC_ACT_SHOT;
1681 ext->chain = last_executed_chain;
1682 }
1683
1684 return ret;
1685 #endif
1686 }
1687 EXPORT_SYMBOL(tcf_classify_ingress);
1688
1689 struct tcf_chain_info {
1690 struct tcf_proto __rcu **pprev;
1691 struct tcf_proto __rcu *next;
1692 };
1693
1694 static struct tcf_proto *tcf_chain_tp_prev(struct tcf_chain *chain,
1695 struct tcf_chain_info *chain_info)
1696 {
1697 return tcf_chain_dereference(*chain_info->pprev, chain);
1698 }
1699
1700 static int tcf_chain_tp_insert(struct tcf_chain *chain,
1701 struct tcf_chain_info *chain_info,
1702 struct tcf_proto *tp)
1703 {
1704 if (chain->flushing)
1705 return -EAGAIN;
1706
1707 if (*chain_info->pprev == chain->filter_chain)
1708 tcf_chain0_head_change(chain, tp);
1709 tcf_proto_get(tp);
1710 RCU_INIT_POINTER(tp->next, tcf_chain_tp_prev(chain, chain_info));
1711 rcu_assign_pointer(*chain_info->pprev, tp);
1712
1713 return 0;
1714 }
1715
1716 static void tcf_chain_tp_remove(struct tcf_chain *chain,
1717 struct tcf_chain_info *chain_info,
1718 struct tcf_proto *tp)
1719 {
1720 struct tcf_proto *next = tcf_chain_dereference(chain_info->next, chain);
1721
1722 tcf_proto_mark_delete(tp);
1723 if (tp == chain->filter_chain)
1724 tcf_chain0_head_change(chain, next);
1725 RCU_INIT_POINTER(*chain_info->pprev, next);
1726 }
1727
1728 static struct tcf_proto *tcf_chain_tp_find(struct tcf_chain *chain,
1729 struct tcf_chain_info *chain_info,
1730 u32 protocol, u32 prio,
1731 bool prio_allocate);
1732
1733 /* Try to insert new proto.
1734 * If proto with specified priority already exists, free new proto
1735 * and return existing one.
1736 */
1737
1738 static struct tcf_proto *tcf_chain_tp_insert_unique(struct tcf_chain *chain,
1739 struct tcf_proto *tp_new,
1740 u32 protocol, u32 prio,
1741 bool rtnl_held)
1742 {
1743 struct tcf_chain_info chain_info;
1744 struct tcf_proto *tp;
1745 int err = 0;
1746
1747 mutex_lock(&chain->filter_chain_lock);
1748
1749 if (tcf_proto_exists_destroying(chain, tp_new)) {
1750 mutex_unlock(&chain->filter_chain_lock);
1751 tcf_proto_destroy(tp_new, rtnl_held, false, NULL);
1752 return ERR_PTR(-EAGAIN);
1753 }
1754
1755 tp = tcf_chain_tp_find(chain, &chain_info,
1756 protocol, prio, false);
1757 if (!tp)
1758 err = tcf_chain_tp_insert(chain, &chain_info, tp_new);
1759 mutex_unlock(&chain->filter_chain_lock);
1760
1761 if (tp) {
1762 tcf_proto_destroy(tp_new, rtnl_held, false, NULL);
1763 tp_new = tp;
1764 } else if (err) {
1765 tcf_proto_destroy(tp_new, rtnl_held, false, NULL);
1766 tp_new = ERR_PTR(err);
1767 }
1768
1769 return tp_new;
1770 }
1771
1772 static void tcf_chain_tp_delete_empty(struct tcf_chain *chain,
1773 struct tcf_proto *tp, bool rtnl_held,
1774 struct netlink_ext_ack *extack)
1775 {
1776 struct tcf_chain_info chain_info;
1777 struct tcf_proto *tp_iter;
1778 struct tcf_proto **pprev;
1779 struct tcf_proto *next;
1780
1781 mutex_lock(&chain->filter_chain_lock);
1782
1783 /* Atomically find and remove tp from chain. */
1784 for (pprev = &chain->filter_chain;
1785 (tp_iter = tcf_chain_dereference(*pprev, chain));
1786 pprev = &tp_iter->next) {
1787 if (tp_iter == tp) {
1788 chain_info.pprev = pprev;
1789 chain_info.next = tp_iter->next;
1790 WARN_ON(tp_iter->deleting);
1791 break;
1792 }
1793 }
1794 /* Verify that tp still exists and no new filters were inserted
1795 * concurrently.
1796 * Mark tp for deletion if it is empty.
1797 */
1798 if (!tp_iter || !tcf_proto_check_delete(tp)) {
1799 mutex_unlock(&chain->filter_chain_lock);
1800 return;
1801 }
1802
1803 tcf_proto_signal_destroying(chain, tp);
1804 next = tcf_chain_dereference(chain_info.next, chain);
1805 if (tp == chain->filter_chain)
1806 tcf_chain0_head_change(chain, next);
1807 RCU_INIT_POINTER(*chain_info.pprev, next);
1808 mutex_unlock(&chain->filter_chain_lock);
1809
1810 tcf_proto_put(tp, rtnl_held, extack);
1811 }
1812
1813 static struct tcf_proto *tcf_chain_tp_find(struct tcf_chain *chain,
1814 struct tcf_chain_info *chain_info,
1815 u32 protocol, u32 prio,
1816 bool prio_allocate)
1817 {
1818 struct tcf_proto **pprev;
1819 struct tcf_proto *tp;
1820
1821 /* Check the chain for existence of proto-tcf with this priority */
1822 for (pprev = &chain->filter_chain;
1823 (tp = tcf_chain_dereference(*pprev, chain));
1824 pprev = &tp->next) {
1825 if (tp->prio >= prio) {
1826 if (tp->prio == prio) {
1827 if (prio_allocate ||
1828 (tp->protocol != protocol && protocol))
1829 return ERR_PTR(-EINVAL);
1830 } else {
1831 tp = NULL;
1832 }
1833 break;
1834 }
1835 }
1836 chain_info->pprev = pprev;
1837 if (tp) {
1838 chain_info->next = tp->next;
1839 tcf_proto_get(tp);
1840 } else {
1841 chain_info->next = NULL;
1842 }
1843 return tp;
1844 }
1845
1846 static int tcf_fill_node(struct net *net, struct sk_buff *skb,
1847 struct tcf_proto *tp, struct tcf_block *block,
1848 struct Qdisc *q, u32 parent, void *fh,
1849 u32 portid, u32 seq, u16 flags, int event,
1850 bool rtnl_held)
1851 {
1852 struct tcmsg *tcm;
1853 struct nlmsghdr *nlh;
1854 unsigned char *b = skb_tail_pointer(skb);
1855
1856 nlh = nlmsg_put(skb, portid, seq, event, sizeof(*tcm), flags);
1857 if (!nlh)
1858 goto out_nlmsg_trim;
1859 tcm = nlmsg_data(nlh);
1860 tcm->tcm_family = AF_UNSPEC;
1861 tcm->tcm__pad1 = 0;
1862 tcm->tcm__pad2 = 0;
1863 if (q) {
1864 tcm->tcm_ifindex = qdisc_dev(q)->ifindex;
1865 tcm->tcm_parent = parent;
1866 } else {
1867 tcm->tcm_ifindex = TCM_IFINDEX_MAGIC_BLOCK;
1868 tcm->tcm_block_index = block->index;
1869 }
1870 tcm->tcm_info = TC_H_MAKE(tp->prio, tp->protocol);
1871 if (nla_put_string(skb, TCA_KIND, tp->ops->kind))
1872 goto nla_put_failure;
1873 if (nla_put_u32(skb, TCA_CHAIN, tp->chain->index))
1874 goto nla_put_failure;
1875 if (!fh) {
1876 tcm->tcm_handle = 0;
1877 } else {
1878 if (tp->ops->dump &&
1879 tp->ops->dump(net, tp, fh, skb, tcm, rtnl_held) < 0)
1880 goto nla_put_failure;
1881 }
1882 nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1883 return skb->len;
1884
1885 out_nlmsg_trim:
1886 nla_put_failure:
1887 nlmsg_trim(skb, b);
1888 return -1;
1889 }
1890
1891 static int tfilter_notify(struct net *net, struct sk_buff *oskb,
1892 struct nlmsghdr *n, struct tcf_proto *tp,
1893 struct tcf_block *block, struct Qdisc *q,
1894 u32 parent, void *fh, int event, bool unicast,
1895 bool rtnl_held)
1896 {
1897 struct sk_buff *skb;
1898 u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
1899 int err = 0;
1900
1901 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1902 if (!skb)
1903 return -ENOBUFS;
1904
1905 if (tcf_fill_node(net, skb, tp, block, q, parent, fh, portid,
1906 n->nlmsg_seq, n->nlmsg_flags, event,
1907 rtnl_held) <= 0) {
1908 kfree_skb(skb);
1909 return -EINVAL;
1910 }
1911
1912 if (unicast)
1913 err = netlink_unicast(net->rtnl, skb, portid, MSG_DONTWAIT);
1914 else
1915 err = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
1916 n->nlmsg_flags & NLM_F_ECHO);
1917
1918 if (err > 0)
1919 err = 0;
1920 return err;
1921 }
1922
1923 static int tfilter_del_notify(struct net *net, struct sk_buff *oskb,
1924 struct nlmsghdr *n, struct tcf_proto *tp,
1925 struct tcf_block *block, struct Qdisc *q,
1926 u32 parent, void *fh, bool unicast, bool *last,
1927 bool rtnl_held, struct netlink_ext_ack *extack)
1928 {
1929 struct sk_buff *skb;
1930 u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
1931 int err;
1932
1933 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1934 if (!skb)
1935 return -ENOBUFS;
1936
1937 if (tcf_fill_node(net, skb, tp, block, q, parent, fh, portid,
1938 n->nlmsg_seq, n->nlmsg_flags, RTM_DELTFILTER,
1939 rtnl_held) <= 0) {
1940 NL_SET_ERR_MSG(extack, "Failed to build del event notification");
1941 kfree_skb(skb);
1942 return -EINVAL;
1943 }
1944
1945 err = tp->ops->delete(tp, fh, last, rtnl_held, extack);
1946 if (err) {
1947 kfree_skb(skb);
1948 return err;
1949 }
1950
1951 if (unicast)
1952 err = netlink_unicast(net->rtnl, skb, portid, MSG_DONTWAIT);
1953 else
1954 err = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
1955 n->nlmsg_flags & NLM_F_ECHO);
1956 if (err < 0)
1957 NL_SET_ERR_MSG(extack, "Failed to send filter delete notification");
1958
1959 if (err > 0)
1960 err = 0;
1961 return err;
1962 }
1963
1964 static void tfilter_notify_chain(struct net *net, struct sk_buff *oskb,
1965 struct tcf_block *block, struct Qdisc *q,
1966 u32 parent, struct nlmsghdr *n,
1967 struct tcf_chain *chain, int event,
1968 bool rtnl_held)
1969 {
1970 struct tcf_proto *tp;
1971
1972 for (tp = tcf_get_next_proto(chain, NULL, rtnl_held);
1973 tp; tp = tcf_get_next_proto(chain, tp, rtnl_held))
1974 tfilter_notify(net, oskb, n, tp, block,
1975 q, parent, NULL, event, false, rtnl_held);
1976 }
1977
1978 static void tfilter_put(struct tcf_proto *tp, void *fh)
1979 {
1980 if (tp->ops->put && fh)
1981 tp->ops->put(tp, fh);
1982 }
1983
1984 static int tc_new_tfilter(struct sk_buff *skb, struct nlmsghdr *n,
1985 struct netlink_ext_ack *extack)
1986 {
1987 struct net *net = sock_net(skb->sk);
1988 struct nlattr *tca[TCA_MAX + 1];
1989 char name[IFNAMSIZ];
1990 struct tcmsg *t;
1991 u32 protocol;
1992 u32 prio;
1993 bool prio_allocate;
1994 u32 parent;
1995 u32 chain_index;
1996 struct Qdisc *q = NULL;
1997 struct tcf_chain_info chain_info;
1998 struct tcf_chain *chain = NULL;
1999 struct tcf_block *block;
2000 struct tcf_proto *tp;
2001 unsigned long cl;
2002 void *fh;
2003 int err;
2004 int tp_created;
2005 bool rtnl_held = false;
2006
2007 if (!netlink_ns_capable(skb, net->user_ns, CAP_NET_ADMIN))
2008 return -EPERM;
2009
2010 replay:
2011 tp_created = 0;
2012
2013 err = nlmsg_parse_deprecated(n, sizeof(*t), tca, TCA_MAX,
2014 rtm_tca_policy, extack);
2015 if (err < 0)
2016 return err;
2017
2018 t = nlmsg_data(n);
2019 protocol = TC_H_MIN(t->tcm_info);
2020 prio = TC_H_MAJ(t->tcm_info);
2021 prio_allocate = false;
2022 parent = t->tcm_parent;
2023 tp = NULL;
2024 cl = 0;
2025 block = NULL;
2026
2027 if (prio == 0) {
2028 /* If no priority is provided by the user,
2029 * we allocate one.
2030 */
2031 if (n->nlmsg_flags & NLM_F_CREATE) {
2032 prio = TC_H_MAKE(0x80000000U, 0U);
2033 prio_allocate = true;
2034 } else {
2035 NL_SET_ERR_MSG(extack, "Invalid filter command with priority of zero");
2036 return -ENOENT;
2037 }
2038 }
2039
2040 /* Find head of filter chain. */
2041
2042 err = __tcf_qdisc_find(net, &q, &parent, t->tcm_ifindex, false, extack);
2043 if (err)
2044 return err;
2045
2046 if (tcf_proto_check_kind(tca[TCA_KIND], name)) {
2047 NL_SET_ERR_MSG(extack, "Specified TC filter name too long");
2048 err = -EINVAL;
2049 goto errout;
2050 }
2051
2052 /* Take rtnl mutex if rtnl_held was set to true on previous iteration,
2053 * block is shared (no qdisc found), qdisc is not unlocked, classifier
2054 * type is not specified, classifier is not unlocked.
2055 */
2056 if (rtnl_held ||
2057 (q && !(q->ops->cl_ops->flags & QDISC_CLASS_OPS_DOIT_UNLOCKED)) ||
2058 !tcf_proto_is_unlocked(name)) {
2059 rtnl_held = true;
2060 rtnl_lock();
2061 }
2062
2063 err = __tcf_qdisc_cl_find(q, parent, &cl, t->tcm_ifindex, extack);
2064 if (err)
2065 goto errout;
2066
2067 block = __tcf_block_find(net, q, cl, t->tcm_ifindex, t->tcm_block_index,
2068 extack);
2069 if (IS_ERR(block)) {
2070 err = PTR_ERR(block);
2071 goto errout;
2072 }
2073 block->classid = parent;
2074
2075 chain_index = tca[TCA_CHAIN] ? nla_get_u32(tca[TCA_CHAIN]) : 0;
2076 if (chain_index > TC_ACT_EXT_VAL_MASK) {
2077 NL_SET_ERR_MSG(extack, "Specified chain index exceeds upper limit");
2078 err = -EINVAL;
2079 goto errout;
2080 }
2081 chain = tcf_chain_get(block, chain_index, true);
2082 if (!chain) {
2083 NL_SET_ERR_MSG(extack, "Cannot create specified filter chain");
2084 err = -ENOMEM;
2085 goto errout;
2086 }
2087
2088 mutex_lock(&chain->filter_chain_lock);
2089 tp = tcf_chain_tp_find(chain, &chain_info, protocol,
2090 prio, prio_allocate);
2091 if (IS_ERR(tp)) {
2092 NL_SET_ERR_MSG(extack, "Filter with specified priority/protocol not found");
2093 err = PTR_ERR(tp);
2094 goto errout_locked;
2095 }
2096
2097 if (tp == NULL) {
2098 struct tcf_proto *tp_new = NULL;
2099
2100 if (chain->flushing) {
2101 err = -EAGAIN;
2102 goto errout_locked;
2103 }
2104
2105 /* Proto-tcf does not exist, create new one */
2106
2107 if (tca[TCA_KIND] == NULL || !protocol) {
2108 NL_SET_ERR_MSG(extack, "Filter kind and protocol must be specified");
2109 err = -EINVAL;
2110 goto errout_locked;
2111 }
2112
2113 if (!(n->nlmsg_flags & NLM_F_CREATE)) {
2114 NL_SET_ERR_MSG(extack, "Need both RTM_NEWTFILTER and NLM_F_CREATE to create a new filter");
2115 err = -ENOENT;
2116 goto errout_locked;
2117 }
2118
2119 if (prio_allocate)
2120 prio = tcf_auto_prio(tcf_chain_tp_prev(chain,
2121 &chain_info));
2122
2123 mutex_unlock(&chain->filter_chain_lock);
2124 tp_new = tcf_proto_create(name, protocol, prio, chain,
2125 rtnl_held, extack);
2126 if (IS_ERR(tp_new)) {
2127 err = PTR_ERR(tp_new);
2128 goto errout_tp;
2129 }
2130
2131 tp_created = 1;
2132 tp = tcf_chain_tp_insert_unique(chain, tp_new, protocol, prio,
2133 rtnl_held);
2134 if (IS_ERR(tp)) {
2135 err = PTR_ERR(tp);
2136 goto errout_tp;
2137 }
2138 } else {
2139 mutex_unlock(&chain->filter_chain_lock);
2140 }
2141
2142 if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], tp->ops->kind)) {
2143 NL_SET_ERR_MSG(extack, "Specified filter kind does not match existing one");
2144 err = -EINVAL;
2145 goto errout;
2146 }
2147
2148 fh = tp->ops->get(tp, t->tcm_handle);
2149
2150 if (!fh) {
2151 if (!(n->nlmsg_flags & NLM_F_CREATE)) {
2152 NL_SET_ERR_MSG(extack, "Need both RTM_NEWTFILTER and NLM_F_CREATE to create a new filter");
2153 err = -ENOENT;
2154 goto errout;
2155 }
2156 } else if (n->nlmsg_flags & NLM_F_EXCL) {
2157 tfilter_put(tp, fh);
2158 NL_SET_ERR_MSG(extack, "Filter already exists");
2159 err = -EEXIST;
2160 goto errout;
2161 }
2162
2163 if (chain->tmplt_ops && chain->tmplt_ops != tp->ops) {
2164 NL_SET_ERR_MSG(extack, "Chain template is set to a different filter kind");
2165 err = -EINVAL;
2166 goto errout;
2167 }
2168
2169 err = tp->ops->change(net, skb, tp, cl, t->tcm_handle, tca, &fh,
2170 n->nlmsg_flags & NLM_F_CREATE ? TCA_ACT_NOREPLACE : TCA_ACT_REPLACE,
2171 rtnl_held, extack);
2172 if (err == 0) {
2173 tfilter_notify(net, skb, n, tp, block, q, parent, fh,
2174 RTM_NEWTFILTER, false, rtnl_held);
2175 tfilter_put(tp, fh);
2176 /* q pointer is NULL for shared blocks */
2177 if (q)
2178 q->flags &= ~TCQ_F_CAN_BYPASS;
2179 }
2180
2181 errout:
2182 if (err && tp_created)
2183 tcf_chain_tp_delete_empty(chain, tp, rtnl_held, NULL);
2184 errout_tp:
2185 if (chain) {
2186 if (tp && !IS_ERR(tp))
2187 tcf_proto_put(tp, rtnl_held, NULL);
2188 if (!tp_created)
2189 tcf_chain_put(chain);
2190 }
2191 tcf_block_release(q, block, rtnl_held);
2192
2193 if (rtnl_held)
2194 rtnl_unlock();
2195
2196 if (err == -EAGAIN) {
2197 /* Take rtnl lock in case EAGAIN is caused by concurrent flush
2198 * of target chain.
2199 */
2200 rtnl_held = true;
2201 /* Replay the request. */
2202 goto replay;
2203 }
2204 return err;
2205
2206 errout_locked:
2207 mutex_unlock(&chain->filter_chain_lock);
2208 goto errout;
2209 }
2210
2211 static int tc_del_tfilter(struct sk_buff *skb, struct nlmsghdr *n,
2212 struct netlink_ext_ack *extack)
2213 {
2214 struct net *net = sock_net(skb->sk);
2215 struct nlattr *tca[TCA_MAX + 1];
2216 char name[IFNAMSIZ];
2217 struct tcmsg *t;
2218 u32 protocol;
2219 u32 prio;
2220 u32 parent;
2221 u32 chain_index;
2222 struct Qdisc *q = NULL;
2223 struct tcf_chain_info chain_info;
2224 struct tcf_chain *chain = NULL;
2225 struct tcf_block *block = NULL;
2226 struct tcf_proto *tp = NULL;
2227 unsigned long cl = 0;
2228 void *fh = NULL;
2229 int err;
2230 bool rtnl_held = false;
2231
2232 if (!netlink_ns_capable(skb, net->user_ns, CAP_NET_ADMIN))
2233 return -EPERM;
2234
2235 err = nlmsg_parse_deprecated(n, sizeof(*t), tca, TCA_MAX,
2236 rtm_tca_policy, extack);
2237 if (err < 0)
2238 return err;
2239
2240 t = nlmsg_data(n);
2241 protocol = TC_H_MIN(t->tcm_info);
2242 prio = TC_H_MAJ(t->tcm_info);
2243 parent = t->tcm_parent;
2244
2245 if (prio == 0 && (protocol || t->tcm_handle || tca[TCA_KIND])) {
2246 NL_SET_ERR_MSG(extack, "Cannot flush filters with protocol, handle or kind set");
2247 return -ENOENT;
2248 }
2249
2250 /* Find head of filter chain. */
2251
2252 err = __tcf_qdisc_find(net, &q, &parent, t->tcm_ifindex, false, extack);
2253 if (err)
2254 return err;
2255
2256 if (tcf_proto_check_kind(tca[TCA_KIND], name)) {
2257 NL_SET_ERR_MSG(extack, "Specified TC filter name too long");
2258 err = -EINVAL;
2259 goto errout;
2260 }
2261 /* Take rtnl mutex if flushing whole chain, block is shared (no qdisc
2262 * found), qdisc is not unlocked, classifier type is not specified,
2263 * classifier is not unlocked.
2264 */
2265 if (!prio ||
2266 (q && !(q->ops->cl_ops->flags & QDISC_CLASS_OPS_DOIT_UNLOCKED)) ||
2267 !tcf_proto_is_unlocked(name)) {
2268 rtnl_held = true;
2269 rtnl_lock();
2270 }
2271
2272 err = __tcf_qdisc_cl_find(q, parent, &cl, t->tcm_ifindex, extack);
2273 if (err)
2274 goto errout;
2275
2276 block = __tcf_block_find(net, q, cl, t->tcm_ifindex, t->tcm_block_index,
2277 extack);
2278 if (IS_ERR(block)) {
2279 err = PTR_ERR(block);
2280 goto errout;
2281 }
2282
2283 chain_index = tca[TCA_CHAIN] ? nla_get_u32(tca[TCA_CHAIN]) : 0;
2284 if (chain_index > TC_ACT_EXT_VAL_MASK) {
2285 NL_SET_ERR_MSG(extack, "Specified chain index exceeds upper limit");
2286 err = -EINVAL;
2287 goto errout;
2288 }
2289 chain = tcf_chain_get(block, chain_index, false);
2290 if (!chain) {
2291 /* User requested flush on non-existent chain. Nothing to do,
2292 * so just return success.
2293 */
2294 if (prio == 0) {
2295 err = 0;
2296 goto errout;
2297 }
2298 NL_SET_ERR_MSG(extack, "Cannot find specified filter chain");
2299 err = -ENOENT;
2300 goto errout;
2301 }
2302
2303 if (prio == 0) {
2304 tfilter_notify_chain(net, skb, block, q, parent, n,
2305 chain, RTM_DELTFILTER, rtnl_held);
2306 tcf_chain_flush(chain, rtnl_held);
2307 err = 0;
2308 goto errout;
2309 }
2310
2311 mutex_lock(&chain->filter_chain_lock);
2312 tp = tcf_chain_tp_find(chain, &chain_info, protocol,
2313 prio, false);
2314 if (!tp || IS_ERR(tp)) {
2315 NL_SET_ERR_MSG(extack, "Filter with specified priority/protocol not found");
2316 err = tp ? PTR_ERR(tp) : -ENOENT;
2317 goto errout_locked;
2318 } else if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], tp->ops->kind)) {
2319 NL_SET_ERR_MSG(extack, "Specified filter kind does not match existing one");
2320 err = -EINVAL;
2321 goto errout_locked;
2322 } else if (t->tcm_handle == 0) {
2323 tcf_proto_signal_destroying(chain, tp);
2324 tcf_chain_tp_remove(chain, &chain_info, tp);
2325 mutex_unlock(&chain->filter_chain_lock);
2326
2327 tcf_proto_put(tp, rtnl_held, NULL);
2328 tfilter_notify(net, skb, n, tp, block, q, parent, fh,
2329 RTM_DELTFILTER, false, rtnl_held);
2330 err = 0;
2331 goto errout;
2332 }
2333 mutex_unlock(&chain->filter_chain_lock);
2334
2335 fh = tp->ops->get(tp, t->tcm_handle);
2336
2337 if (!fh) {
2338 NL_SET_ERR_MSG(extack, "Specified filter handle not found");
2339 err = -ENOENT;
2340 } else {
2341 bool last;
2342
2343 err = tfilter_del_notify(net, skb, n, tp, block,
2344 q, parent, fh, false, &last,
2345 rtnl_held, extack);
2346
2347 if (err)
2348 goto errout;
2349 if (last)
2350 tcf_chain_tp_delete_empty(chain, tp, rtnl_held, extack);
2351 }
2352
2353 errout:
2354 if (chain) {
2355 if (tp && !IS_ERR(tp))
2356 tcf_proto_put(tp, rtnl_held, NULL);
2357 tcf_chain_put(chain);
2358 }
2359 tcf_block_release(q, block, rtnl_held);
2360
2361 if (rtnl_held)
2362 rtnl_unlock();
2363
2364 return err;
2365
2366 errout_locked:
2367 mutex_unlock(&chain->filter_chain_lock);
2368 goto errout;
2369 }
2370
2371 static int tc_get_tfilter(struct sk_buff *skb, struct nlmsghdr *n,
2372 struct netlink_ext_ack *extack)
2373 {
2374 struct net *net = sock_net(skb->sk);
2375 struct nlattr *tca[TCA_MAX + 1];
2376 char name[IFNAMSIZ];
2377 struct tcmsg *t;
2378 u32 protocol;
2379 u32 prio;
2380 u32 parent;
2381 u32 chain_index;
2382 struct Qdisc *q = NULL;
2383 struct tcf_chain_info chain_info;
2384 struct tcf_chain *chain = NULL;
2385 struct tcf_block *block = NULL;
2386 struct tcf_proto *tp = NULL;
2387 unsigned long cl = 0;
2388 void *fh = NULL;
2389 int err;
2390 bool rtnl_held = false;
2391
2392 err = nlmsg_parse_deprecated(n, sizeof(*t), tca, TCA_MAX,
2393 rtm_tca_policy, extack);
2394 if (err < 0)
2395 return err;
2396
2397 t = nlmsg_data(n);
2398 protocol = TC_H_MIN(t->tcm_info);
2399 prio = TC_H_MAJ(t->tcm_info);
2400 parent = t->tcm_parent;
2401
2402 if (prio == 0) {
2403 NL_SET_ERR_MSG(extack, "Invalid filter command with priority of zero");
2404 return -ENOENT;
2405 }
2406
2407 /* Find head of filter chain. */
2408
2409 err = __tcf_qdisc_find(net, &q, &parent, t->tcm_ifindex, false, extack);
2410 if (err)
2411 return err;
2412
2413 if (tcf_proto_check_kind(tca[TCA_KIND], name)) {
2414 NL_SET_ERR_MSG(extack, "Specified TC filter name too long");
2415 err = -EINVAL;
2416 goto errout;
2417 }
2418 /* Take rtnl mutex if block is shared (no qdisc found), qdisc is not
2419 * unlocked, classifier type is not specified, classifier is not
2420 * unlocked.
2421 */
2422 if ((q && !(q->ops->cl_ops->flags & QDISC_CLASS_OPS_DOIT_UNLOCKED)) ||
2423 !tcf_proto_is_unlocked(name)) {
2424 rtnl_held = true;
2425 rtnl_lock();
2426 }
2427
2428 err = __tcf_qdisc_cl_find(q, parent, &cl, t->tcm_ifindex, extack);
2429 if (err)
2430 goto errout;
2431
2432 block = __tcf_block_find(net, q, cl, t->tcm_ifindex, t->tcm_block_index,
2433 extack);
2434 if (IS_ERR(block)) {
2435 err = PTR_ERR(block);
2436 goto errout;
2437 }
2438
2439 chain_index = tca[TCA_CHAIN] ? nla_get_u32(tca[TCA_CHAIN]) : 0;
2440 if (chain_index > TC_ACT_EXT_VAL_MASK) {
2441 NL_SET_ERR_MSG(extack, "Specified chain index exceeds upper limit");
2442 err = -EINVAL;
2443 goto errout;
2444 }
2445 chain = tcf_chain_get(block, chain_index, false);
2446 if (!chain) {
2447 NL_SET_ERR_MSG(extack, "Cannot find specified filter chain");
2448 err = -EINVAL;
2449 goto errout;
2450 }
2451
2452 mutex_lock(&chain->filter_chain_lock);
2453 tp = tcf_chain_tp_find(chain, &chain_info, protocol,
2454 prio, false);
2455 mutex_unlock(&chain->filter_chain_lock);
2456 if (!tp || IS_ERR(tp)) {
2457 NL_SET_ERR_MSG(extack, "Filter with specified priority/protocol not found");
2458 err = tp ? PTR_ERR(tp) : -ENOENT;
2459 goto errout;
2460 } else if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], tp->ops->kind)) {
2461 NL_SET_ERR_MSG(extack, "Specified filter kind does not match existing one");
2462 err = -EINVAL;
2463 goto errout;
2464 }
2465
2466 fh = tp->ops->get(tp, t->tcm_handle);
2467
2468 if (!fh) {
2469 NL_SET_ERR_MSG(extack, "Specified filter handle not found");
2470 err = -ENOENT;
2471 } else {
2472 err = tfilter_notify(net, skb, n, tp, block, q, parent,
2473 fh, RTM_NEWTFILTER, true, rtnl_held);
2474 if (err < 0)
2475 NL_SET_ERR_MSG(extack, "Failed to send filter notify message");
2476 }
2477
2478 tfilter_put(tp, fh);
2479 errout:
2480 if (chain) {
2481 if (tp && !IS_ERR(tp))
2482 tcf_proto_put(tp, rtnl_held, NULL);
2483 tcf_chain_put(chain);
2484 }
2485 tcf_block_release(q, block, rtnl_held);
2486
2487 if (rtnl_held)
2488 rtnl_unlock();
2489
2490 return err;
2491 }
2492
2493 struct tcf_dump_args {
2494 struct tcf_walker w;
2495 struct sk_buff *skb;
2496 struct netlink_callback *cb;
2497 struct tcf_block *block;
2498 struct Qdisc *q;
2499 u32 parent;
2500 };
2501
2502 static int tcf_node_dump(struct tcf_proto *tp, void *n, struct tcf_walker *arg)
2503 {
2504 struct tcf_dump_args *a = (void *)arg;
2505 struct net *net = sock_net(a->skb->sk);
2506
2507 return tcf_fill_node(net, a->skb, tp, a->block, a->q, a->parent,
2508 n, NETLINK_CB(a->cb->skb).portid,
2509 a->cb->nlh->nlmsg_seq, NLM_F_MULTI,
2510 RTM_NEWTFILTER, true);
2511 }
2512
2513 static bool tcf_chain_dump(struct tcf_chain *chain, struct Qdisc *q, u32 parent,
2514 struct sk_buff *skb, struct netlink_callback *cb,
2515 long index_start, long *p_index)
2516 {
2517 struct net *net = sock_net(skb->sk);
2518 struct tcf_block *block = chain->block;
2519 struct tcmsg *tcm = nlmsg_data(cb->nlh);
2520 struct tcf_proto *tp, *tp_prev;
2521 struct tcf_dump_args arg;
2522
2523 for (tp = __tcf_get_next_proto(chain, NULL);
2524 tp;
2525 tp_prev = tp,
2526 tp = __tcf_get_next_proto(chain, tp),
2527 tcf_proto_put(tp_prev, true, NULL),
2528 (*p_index)++) {
2529 if (*p_index < index_start)
2530 continue;
2531 if (TC_H_MAJ(tcm->tcm_info) &&
2532 TC_H_MAJ(tcm->tcm_info) != tp->prio)
2533 continue;
2534 if (TC_H_MIN(tcm->tcm_info) &&
2535 TC_H_MIN(tcm->tcm_info) != tp->protocol)
2536 continue;
2537 if (*p_index > index_start)
2538 memset(&cb->args[1], 0,
2539 sizeof(cb->args) - sizeof(cb->args[0]));
2540 if (cb->args[1] == 0) {
2541 if (tcf_fill_node(net, skb, tp, block, q, parent, NULL,
2542 NETLINK_CB(cb->skb).portid,
2543 cb->nlh->nlmsg_seq, NLM_F_MULTI,
2544 RTM_NEWTFILTER, true) <= 0)
2545 goto errout;
2546 cb->args[1] = 1;
2547 }
2548 if (!tp->ops->walk)
2549 continue;
2550 arg.w.fn = tcf_node_dump;
2551 arg.skb = skb;
2552 arg.cb = cb;
2553 arg.block = block;
2554 arg.q = q;
2555 arg.parent = parent;
2556 arg.w.stop = 0;
2557 arg.w.skip = cb->args[1] - 1;
2558 arg.w.count = 0;
2559 arg.w.cookie = cb->args[2];
2560 tp->ops->walk(tp, &arg.w, true);
2561 cb->args[2] = arg.w.cookie;
2562 cb->args[1] = arg.w.count + 1;
2563 if (arg.w.stop)
2564 goto errout;
2565 }
2566 return true;
2567
2568 errout:
2569 tcf_proto_put(tp, true, NULL);
2570 return false;
2571 }
2572
2573 /* called with RTNL */
2574 static int tc_dump_tfilter(struct sk_buff *skb, struct netlink_callback *cb)
2575 {
2576 struct tcf_chain *chain, *chain_prev;
2577 struct net *net = sock_net(skb->sk);
2578 struct nlattr *tca[TCA_MAX + 1];
2579 struct Qdisc *q = NULL;
2580 struct tcf_block *block;
2581 struct tcmsg *tcm = nlmsg_data(cb->nlh);
2582 long index_start;
2583 long index;
2584 u32 parent;
2585 int err;
2586
2587 if (nlmsg_len(cb->nlh) < sizeof(*tcm))
2588 return skb->len;
2589
2590 err = nlmsg_parse_deprecated(cb->nlh, sizeof(*tcm), tca, TCA_MAX,
2591 NULL, cb->extack);
2592 if (err)
2593 return err;
2594
2595 if (tcm->tcm_ifindex == TCM_IFINDEX_MAGIC_BLOCK) {
2596 block = tcf_block_refcnt_get(net, tcm->tcm_block_index);
2597 if (!block)
2598 goto out;
2599 /* If we work with block index, q is NULL and parent value
2600 * will never be used in the following code. The check
2601 * in tcf_fill_node prevents it. However, compiler does not
2602 * see that far, so set parent to zero to silence the warning
2603 * about parent being uninitialized.
2604 */
2605 parent = 0;
2606 } else {
2607 const struct Qdisc_class_ops *cops;
2608 struct net_device *dev;
2609 unsigned long cl = 0;
2610
2611 dev = __dev_get_by_index(net, tcm->tcm_ifindex);
2612 if (!dev)
2613 return skb->len;
2614
2615 parent = tcm->tcm_parent;
2616 if (!parent)
2617 q = dev->qdisc;
2618 else
2619 q = qdisc_lookup(dev, TC_H_MAJ(tcm->tcm_parent));
2620 if (!q)
2621 goto out;
2622 cops = q->ops->cl_ops;
2623 if (!cops)
2624 goto out;
2625 if (!cops->tcf_block)
2626 goto out;
2627 if (TC_H_MIN(tcm->tcm_parent)) {
2628 cl = cops->find(q, tcm->tcm_parent);
2629 if (cl == 0)
2630 goto out;
2631 }
2632 block = cops->tcf_block(q, cl, NULL);
2633 if (!block)
2634 goto out;
2635 parent = block->classid;
2636 if (tcf_block_shared(block))
2637 q = NULL;
2638 }
2639
2640 index_start = cb->args[0];
2641 index = 0;
2642
2643 for (chain = __tcf_get_next_chain(block, NULL);
2644 chain;
2645 chain_prev = chain,
2646 chain = __tcf_get_next_chain(block, chain),
2647 tcf_chain_put(chain_prev)) {
2648 if (tca[TCA_CHAIN] &&
2649 nla_get_u32(tca[TCA_CHAIN]) != chain->index)
2650 continue;
2651 if (!tcf_chain_dump(chain, q, parent, skb, cb,
2652 index_start, &index)) {
2653 tcf_chain_put(chain);
2654 err = -EMSGSIZE;
2655 break;
2656 }
2657 }
2658
2659 if (tcm->tcm_ifindex == TCM_IFINDEX_MAGIC_BLOCK)
2660 tcf_block_refcnt_put(block, true);
2661 cb->args[0] = index;
2662
2663 out:
2664 /* If we did no progress, the error (EMSGSIZE) is real */
2665 if (skb->len == 0 && err)
2666 return err;
2667 return skb->len;
2668 }
2669
2670 static int tc_chain_fill_node(const struct tcf_proto_ops *tmplt_ops,
2671 void *tmplt_priv, u32 chain_index,
2672 struct net *net, struct sk_buff *skb,
2673 struct tcf_block *block,
2674 u32 portid, u32 seq, u16 flags, int event)
2675 {
2676 unsigned char *b = skb_tail_pointer(skb);
2677 const struct tcf_proto_ops *ops;
2678 struct nlmsghdr *nlh;
2679 struct tcmsg *tcm;
2680 void *priv;
2681
2682 ops = tmplt_ops;
2683 priv = tmplt_priv;
2684
2685 nlh = nlmsg_put(skb, portid, seq, event, sizeof(*tcm), flags);
2686 if (!nlh)
2687 goto out_nlmsg_trim;
2688 tcm = nlmsg_data(nlh);
2689 tcm->tcm_family = AF_UNSPEC;
2690 tcm->tcm__pad1 = 0;
2691 tcm->tcm__pad2 = 0;
2692 tcm->tcm_handle = 0;
2693 if (block->q) {
2694 tcm->tcm_ifindex = qdisc_dev(block->q)->ifindex;
2695 tcm->tcm_parent = block->q->handle;
2696 } else {
2697 tcm->tcm_ifindex = TCM_IFINDEX_MAGIC_BLOCK;
2698 tcm->tcm_block_index = block->index;
2699 }
2700
2701 if (nla_put_u32(skb, TCA_CHAIN, chain_index))
2702 goto nla_put_failure;
2703
2704 if (ops) {
2705 if (nla_put_string(skb, TCA_KIND, ops->kind))
2706 goto nla_put_failure;
2707 if (ops->tmplt_dump(skb, net, priv) < 0)
2708 goto nla_put_failure;
2709 }
2710
2711 nlh->nlmsg_len = skb_tail_pointer(skb) - b;
2712 return skb->len;
2713
2714 out_nlmsg_trim:
2715 nla_put_failure:
2716 nlmsg_trim(skb, b);
2717 return -EMSGSIZE;
2718 }
2719
2720 static int tc_chain_notify(struct tcf_chain *chain, struct sk_buff *oskb,
2721 u32 seq, u16 flags, int event, bool unicast)
2722 {
2723 u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
2724 struct tcf_block *block = chain->block;
2725 struct net *net = block->net;
2726 struct sk_buff *skb;
2727 int err = 0;
2728
2729 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
2730 if (!skb)
2731 return -ENOBUFS;
2732
2733 if (tc_chain_fill_node(chain->tmplt_ops, chain->tmplt_priv,
2734 chain->index, net, skb, block, portid,
2735 seq, flags, event) <= 0) {
2736 kfree_skb(skb);
2737 return -EINVAL;
2738 }
2739
2740 if (unicast)
2741 err = netlink_unicast(net->rtnl, skb, portid, MSG_DONTWAIT);
2742 else
2743 err = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
2744 flags & NLM_F_ECHO);
2745
2746 if (err > 0)
2747 err = 0;
2748 return err;
2749 }
2750
2751 static int tc_chain_notify_delete(const struct tcf_proto_ops *tmplt_ops,
2752 void *tmplt_priv, u32 chain_index,
2753 struct tcf_block *block, struct sk_buff *oskb,
2754 u32 seq, u16 flags, bool unicast)
2755 {
2756 u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
2757 struct net *net = block->net;
2758 struct sk_buff *skb;
2759
2760 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
2761 if (!skb)
2762 return -ENOBUFS;
2763
2764 if (tc_chain_fill_node(tmplt_ops, tmplt_priv, chain_index, net, skb,
2765 block, portid, seq, flags, RTM_DELCHAIN) <= 0) {
2766 kfree_skb(skb);
2767 return -EINVAL;
2768 }
2769
2770 if (unicast)
2771 return netlink_unicast(net->rtnl, skb, portid, MSG_DONTWAIT);
2772
2773 return rtnetlink_send(skb, net, portid, RTNLGRP_TC, flags & NLM_F_ECHO);
2774 }
2775
2776 static int tc_chain_tmplt_add(struct tcf_chain *chain, struct net *net,
2777 struct nlattr **tca,
2778 struct netlink_ext_ack *extack)
2779 {
2780 const struct tcf_proto_ops *ops;
2781 char name[IFNAMSIZ];
2782 void *tmplt_priv;
2783
2784 /* If kind is not set, user did not specify template. */
2785 if (!tca[TCA_KIND])
2786 return 0;
2787
2788 if (tcf_proto_check_kind(tca[TCA_KIND], name)) {
2789 NL_SET_ERR_MSG(extack, "Specified TC chain template name too long");
2790 return -EINVAL;
2791 }
2792
2793 ops = tcf_proto_lookup_ops(name, true, extack);
2794 if (IS_ERR(ops))
2795 return PTR_ERR(ops);
2796 if (!ops->tmplt_create || !ops->tmplt_destroy || !ops->tmplt_dump) {
2797 NL_SET_ERR_MSG(extack, "Chain templates are not supported with specified classifier");
2798 return -EOPNOTSUPP;
2799 }
2800
2801 tmplt_priv = ops->tmplt_create(net, chain, tca, extack);
2802 if (IS_ERR(tmplt_priv)) {
2803 module_put(ops->owner);
2804 return PTR_ERR(tmplt_priv);
2805 }
2806 chain->tmplt_ops = ops;
2807 chain->tmplt_priv = tmplt_priv;
2808 return 0;
2809 }
2810
2811 static void tc_chain_tmplt_del(const struct tcf_proto_ops *tmplt_ops,
2812 void *tmplt_priv)
2813 {
2814 /* If template ops are set, no work to do for us. */
2815 if (!tmplt_ops)
2816 return;
2817
2818 tmplt_ops->tmplt_destroy(tmplt_priv);
2819 module_put(tmplt_ops->owner);
2820 }
2821
2822 /* Add/delete/get a chain */
2823
2824 static int tc_ctl_chain(struct sk_buff *skb, struct nlmsghdr *n,
2825 struct netlink_ext_ack *extack)
2826 {
2827 struct net *net = sock_net(skb->sk);
2828 struct nlattr *tca[TCA_MAX + 1];
2829 struct tcmsg *t;
2830 u32 parent;
2831 u32 chain_index;
2832 struct Qdisc *q = NULL;
2833 struct tcf_chain *chain = NULL;
2834 struct tcf_block *block;
2835 unsigned long cl;
2836 int err;
2837
2838 if (n->nlmsg_type != RTM_GETCHAIN &&
2839 !netlink_ns_capable(skb, net->user_ns, CAP_NET_ADMIN))
2840 return -EPERM;
2841
2842 replay:
2843 err = nlmsg_parse_deprecated(n, sizeof(*t), tca, TCA_MAX,
2844 rtm_tca_policy, extack);
2845 if (err < 0)
2846 return err;
2847
2848 t = nlmsg_data(n);
2849 parent = t->tcm_parent;
2850 cl = 0;
2851
2852 block = tcf_block_find(net, &q, &parent, &cl,
2853 t->tcm_ifindex, t->tcm_block_index, extack);
2854 if (IS_ERR(block))
2855 return PTR_ERR(block);
2856
2857 chain_index = tca[TCA_CHAIN] ? nla_get_u32(tca[TCA_CHAIN]) : 0;
2858 if (chain_index > TC_ACT_EXT_VAL_MASK) {
2859 NL_SET_ERR_MSG(extack, "Specified chain index exceeds upper limit");
2860 err = -EINVAL;
2861 goto errout_block;
2862 }
2863
2864 mutex_lock(&block->lock);
2865 chain = tcf_chain_lookup(block, chain_index);
2866 if (n->nlmsg_type == RTM_NEWCHAIN) {
2867 if (chain) {
2868 if (tcf_chain_held_by_acts_only(chain)) {
2869 /* The chain exists only because there is
2870 * some action referencing it.
2871 */
2872 tcf_chain_hold(chain);
2873 } else {
2874 NL_SET_ERR_MSG(extack, "Filter chain already exists");
2875 err = -EEXIST;
2876 goto errout_block_locked;
2877 }
2878 } else {
2879 if (!(n->nlmsg_flags & NLM_F_CREATE)) {
2880 NL_SET_ERR_MSG(extack, "Need both RTM_NEWCHAIN and NLM_F_CREATE to create a new chain");
2881 err = -ENOENT;
2882 goto errout_block_locked;
2883 }
2884 chain = tcf_chain_create(block, chain_index);
2885 if (!chain) {
2886 NL_SET_ERR_MSG(extack, "Failed to create filter chain");
2887 err = -ENOMEM;
2888 goto errout_block_locked;
2889 }
2890 }
2891 } else {
2892 if (!chain || tcf_chain_held_by_acts_only(chain)) {
2893 NL_SET_ERR_MSG(extack, "Cannot find specified filter chain");
2894 err = -EINVAL;
2895 goto errout_block_locked;
2896 }
2897 tcf_chain_hold(chain);
2898 }
2899
2900 if (n->nlmsg_type == RTM_NEWCHAIN) {
2901 /* Modifying chain requires holding parent block lock. In case
2902 * the chain was successfully added, take a reference to the
2903 * chain. This ensures that an empty chain does not disappear at
2904 * the end of this function.
2905 */
2906 tcf_chain_hold(chain);
2907 chain->explicitly_created = true;
2908 }
2909 mutex_unlock(&block->lock);
2910
2911 switch (n->nlmsg_type) {
2912 case RTM_NEWCHAIN:
2913 err = tc_chain_tmplt_add(chain, net, tca, extack);
2914 if (err) {
2915 tcf_chain_put_explicitly_created(chain);
2916 goto errout;
2917 }
2918
2919 tc_chain_notify(chain, NULL, 0, NLM_F_CREATE | NLM_F_EXCL,
2920 RTM_NEWCHAIN, false);
2921 break;
2922 case RTM_DELCHAIN:
2923 tfilter_notify_chain(net, skb, block, q, parent, n,
2924 chain, RTM_DELTFILTER, true);
2925 /* Flush the chain first as the user requested chain removal. */
2926 tcf_chain_flush(chain, true);
2927 /* In case the chain was successfully deleted, put a reference
2928 * to the chain previously taken during addition.
2929 */
2930 tcf_chain_put_explicitly_created(chain);
2931 break;
2932 case RTM_GETCHAIN:
2933 err = tc_chain_notify(chain, skb, n->nlmsg_seq,
2934 n->nlmsg_seq, n->nlmsg_type, true);
2935 if (err < 0)
2936 NL_SET_ERR_MSG(extack, "Failed to send chain notify message");
2937 break;
2938 default:
2939 err = -EOPNOTSUPP;
2940 NL_SET_ERR_MSG(extack, "Unsupported message type");
2941 goto errout;
2942 }
2943
2944 errout:
2945 tcf_chain_put(chain);
2946 errout_block:
2947 tcf_block_release(q, block, true);
2948 if (err == -EAGAIN)
2949 /* Replay the request. */
2950 goto replay;
2951 return err;
2952
2953 errout_block_locked:
2954 mutex_unlock(&block->lock);
2955 goto errout_block;
2956 }
2957
2958 /* called with RTNL */
2959 static int tc_dump_chain(struct sk_buff *skb, struct netlink_callback *cb)
2960 {
2961 struct net *net = sock_net(skb->sk);
2962 struct nlattr *tca[TCA_MAX + 1];
2963 struct Qdisc *q = NULL;
2964 struct tcf_block *block;
2965 struct tcmsg *tcm = nlmsg_data(cb->nlh);
2966 struct tcf_chain *chain;
2967 long index_start;
2968 long index;
2969 u32 parent;
2970 int err;
2971
2972 if (nlmsg_len(cb->nlh) < sizeof(*tcm))
2973 return skb->len;
2974
2975 err = nlmsg_parse_deprecated(cb->nlh, sizeof(*tcm), tca, TCA_MAX,
2976 rtm_tca_policy, cb->extack);
2977 if (err)
2978 return err;
2979
2980 if (tcm->tcm_ifindex == TCM_IFINDEX_MAGIC_BLOCK) {
2981 block = tcf_block_refcnt_get(net, tcm->tcm_block_index);
2982 if (!block)
2983 goto out;
2984 /* If we work with block index, q is NULL and parent value
2985 * will never be used in the following code. The check
2986 * in tcf_fill_node prevents it. However, compiler does not
2987 * see that far, so set parent to zero to silence the warning
2988 * about parent being uninitialized.
2989 */
2990 parent = 0;
2991 } else {
2992 const struct Qdisc_class_ops *cops;
2993 struct net_device *dev;
2994 unsigned long cl = 0;
2995
2996 dev = __dev_get_by_index(net, tcm->tcm_ifindex);
2997 if (!dev)
2998 return skb->len;
2999
3000 parent = tcm->tcm_parent;
3001 if (!parent) {
3002 q = dev->qdisc;
3003 parent = q->handle;
3004 } else {
3005 q = qdisc_lookup(dev, TC_H_MAJ(tcm->tcm_parent));
3006 }
3007 if (!q)
3008 goto out;
3009 cops = q->ops->cl_ops;
3010 if (!cops)
3011 goto out;
3012 if (!cops->tcf_block)
3013 goto out;
3014 if (TC_H_MIN(tcm->tcm_parent)) {
3015 cl = cops->find(q, tcm->tcm_parent);
3016 if (cl == 0)
3017 goto out;
3018 }
3019 block = cops->tcf_block(q, cl, NULL);
3020 if (!block)
3021 goto out;
3022 if (tcf_block_shared(block))
3023 q = NULL;
3024 }
3025
3026 index_start = cb->args[0];
3027 index = 0;
3028
3029 mutex_lock(&block->lock);
3030 list_for_each_entry(chain, &block->chain_list, list) {
3031 if ((tca[TCA_CHAIN] &&
3032 nla_get_u32(tca[TCA_CHAIN]) != chain->index))
3033 continue;
3034 if (index < index_start) {
3035 index++;
3036 continue;
3037 }
3038 if (tcf_chain_held_by_acts_only(chain))
3039 continue;
3040 err = tc_chain_fill_node(chain->tmplt_ops, chain->tmplt_priv,
3041 chain->index, net, skb, block,
3042 NETLINK_CB(cb->skb).portid,
3043 cb->nlh->nlmsg_seq, NLM_F_MULTI,
3044 RTM_NEWCHAIN);
3045 if (err <= 0)
3046 break;
3047 index++;
3048 }
3049 mutex_unlock(&block->lock);
3050
3051 if (tcm->tcm_ifindex == TCM_IFINDEX_MAGIC_BLOCK)
3052 tcf_block_refcnt_put(block, true);
3053 cb->args[0] = index;
3054
3055 out:
3056 /* If we did no progress, the error (EMSGSIZE) is real */
3057 if (skb->len == 0 && err)
3058 return err;
3059 return skb->len;
3060 }
3061
3062 void tcf_exts_destroy(struct tcf_exts *exts)
3063 {
3064 #ifdef CONFIG_NET_CLS_ACT
3065 if (exts->actions) {
3066 tcf_action_destroy(exts->actions, TCA_ACT_UNBIND);
3067 kfree(exts->actions);
3068 }
3069 exts->nr_actions = 0;
3070 #endif
3071 }
3072 EXPORT_SYMBOL(tcf_exts_destroy);
3073
3074 int tcf_exts_validate(struct net *net, struct tcf_proto *tp, struct nlattr **tb,
3075 struct nlattr *rate_tlv, struct tcf_exts *exts, bool ovr,
3076 bool rtnl_held, struct netlink_ext_ack *extack)
3077 {
3078 #ifdef CONFIG_NET_CLS_ACT
3079 {
3080 struct tc_action *act;
3081 size_t attr_size = 0;
3082
3083 if (exts->police && tb[exts->police]) {
3084 act = tcf_action_init_1(net, tp, tb[exts->police],
3085 rate_tlv, "police", ovr,
3086 TCA_ACT_BIND, rtnl_held,
3087 extack);
3088 if (IS_ERR(act))
3089 return PTR_ERR(act);
3090
3091 act->type = exts->type = TCA_OLD_COMPAT;
3092 exts->actions[0] = act;
3093 exts->nr_actions = 1;
3094 } else if (exts->action && tb[exts->action]) {
3095 int err;
3096
3097 err = tcf_action_init(net, tp, tb[exts->action],
3098 rate_tlv, NULL, ovr, TCA_ACT_BIND,
3099 exts->actions, &attr_size,
3100 rtnl_held, extack);
3101 if (err < 0)
3102 return err;
3103 exts->nr_actions = err;
3104 }
3105 }
3106 #else
3107 if ((exts->action && tb[exts->action]) ||
3108 (exts->police && tb[exts->police])) {
3109 NL_SET_ERR_MSG(extack, "Classifier actions are not supported per compile options (CONFIG_NET_CLS_ACT)");
3110 return -EOPNOTSUPP;
3111 }
3112 #endif
3113
3114 return 0;
3115 }
3116 EXPORT_SYMBOL(tcf_exts_validate);
3117
3118 void tcf_exts_change(struct tcf_exts *dst, struct tcf_exts *src)
3119 {
3120 #ifdef CONFIG_NET_CLS_ACT
3121 struct tcf_exts old = *dst;
3122
3123 *dst = *src;
3124 tcf_exts_destroy(&old);
3125 #endif
3126 }
3127 EXPORT_SYMBOL(tcf_exts_change);
3128
3129 #ifdef CONFIG_NET_CLS_ACT
3130 static struct tc_action *tcf_exts_first_act(struct tcf_exts *exts)
3131 {
3132 if (exts->nr_actions == 0)
3133 return NULL;
3134 else
3135 return exts->actions[0];
3136 }
3137 #endif
3138
3139 int tcf_exts_dump(struct sk_buff *skb, struct tcf_exts *exts)
3140 {
3141 #ifdef CONFIG_NET_CLS_ACT
3142 struct nlattr *nest;
3143
3144 if (exts->action && tcf_exts_has_actions(exts)) {
3145 /*
3146 * again for backward compatible mode - we want
3147 * to work with both old and new modes of entering
3148 * tc data even if iproute2 was newer - jhs
3149 */
3150 if (exts->type != TCA_OLD_COMPAT) {
3151 nest = nla_nest_start_noflag(skb, exts->action);
3152 if (nest == NULL)
3153 goto nla_put_failure;
3154
3155 if (tcf_action_dump(skb, exts->actions, 0, 0) < 0)
3156 goto nla_put_failure;
3157 nla_nest_end(skb, nest);
3158 } else if (exts->police) {
3159 struct tc_action *act = tcf_exts_first_act(exts);
3160 nest = nla_nest_start_noflag(skb, exts->police);
3161 if (nest == NULL || !act)
3162 goto nla_put_failure;
3163 if (tcf_action_dump_old(skb, act, 0, 0) < 0)
3164 goto nla_put_failure;
3165 nla_nest_end(skb, nest);
3166 }
3167 }
3168 return 0;
3169
3170 nla_put_failure:
3171 nla_nest_cancel(skb, nest);
3172 return -1;
3173 #else
3174 return 0;
3175 #endif
3176 }
3177 EXPORT_SYMBOL(tcf_exts_dump);
3178
3179
3180 int tcf_exts_dump_stats(struct sk_buff *skb, struct tcf_exts *exts)
3181 {
3182 #ifdef CONFIG_NET_CLS_ACT
3183 struct tc_action *a = tcf_exts_first_act(exts);
3184 if (a != NULL && tcf_action_copy_stats(skb, a, 1) < 0)
3185 return -1;
3186 #endif
3187 return 0;
3188 }
3189 EXPORT_SYMBOL(tcf_exts_dump_stats);
3190
3191 static void tcf_block_offload_inc(struct tcf_block *block, u32 *flags)
3192 {
3193 if (*flags & TCA_CLS_FLAGS_IN_HW)
3194 return;
3195 *flags |= TCA_CLS_FLAGS_IN_HW;
3196 atomic_inc(&block->offloadcnt);
3197 }
3198
3199 static void tcf_block_offload_dec(struct tcf_block *block, u32 *flags)
3200 {
3201 if (!(*flags & TCA_CLS_FLAGS_IN_HW))
3202 return;
3203 *flags &= ~TCA_CLS_FLAGS_IN_HW;
3204 atomic_dec(&block->offloadcnt);
3205 }
3206
3207 static void tc_cls_offload_cnt_update(struct tcf_block *block,
3208 struct tcf_proto *tp, u32 *cnt,
3209 u32 *flags, u32 diff, bool add)
3210 {
3211 lockdep_assert_held(&block->cb_lock);
3212
3213 spin_lock(&tp->lock);
3214 if (add) {
3215 if (!*cnt)
3216 tcf_block_offload_inc(block, flags);
3217 *cnt += diff;
3218 } else {
3219 *cnt -= diff;
3220 if (!*cnt)
3221 tcf_block_offload_dec(block, flags);
3222 }
3223 spin_unlock(&tp->lock);
3224 }
3225
3226 static void
3227 tc_cls_offload_cnt_reset(struct tcf_block *block, struct tcf_proto *tp,
3228 u32 *cnt, u32 *flags)
3229 {
3230 lockdep_assert_held(&block->cb_lock);
3231
3232 spin_lock(&tp->lock);
3233 tcf_block_offload_dec(block, flags);
3234 *cnt = 0;
3235 spin_unlock(&tp->lock);
3236 }
3237
3238 static int
3239 __tc_setup_cb_call(struct tcf_block *block, enum tc_setup_type type,
3240 void *type_data, bool err_stop)
3241 {
3242 struct flow_block_cb *block_cb;
3243 int ok_count = 0;
3244 int err;
3245
3246 list_for_each_entry(block_cb, &block->flow_block.cb_list, list) {
3247 err = block_cb->cb(type, type_data, block_cb->cb_priv);
3248 if (err) {
3249 if (err_stop)
3250 return err;
3251 } else {
3252 ok_count++;
3253 }
3254 }
3255 return ok_count;
3256 }
3257
3258 int tc_setup_cb_call(struct tcf_block *block, enum tc_setup_type type,
3259 void *type_data, bool err_stop, bool rtnl_held)
3260 {
3261 bool take_rtnl = READ_ONCE(block->lockeddevcnt) && !rtnl_held;
3262 int ok_count;
3263
3264 retry:
3265 if (take_rtnl)
3266 rtnl_lock();
3267 down_read(&block->cb_lock);
3268 /* Need to obtain rtnl lock if block is bound to devs that require it.
3269 * In block bind code cb_lock is obtained while holding rtnl, so we must
3270 * obtain the locks in same order here.
3271 */
3272 if (!rtnl_held && !take_rtnl && block->lockeddevcnt) {
3273 up_read(&block->cb_lock);
3274 take_rtnl = true;
3275 goto retry;
3276 }
3277
3278 ok_count = __tc_setup_cb_call(block, type, type_data, err_stop);
3279
3280 up_read(&block->cb_lock);
3281 if (take_rtnl)
3282 rtnl_unlock();
3283 return ok_count;
3284 }
3285 EXPORT_SYMBOL(tc_setup_cb_call);
3286
3287 /* Non-destructive filter add. If filter that wasn't already in hardware is
3288 * successfully offloaded, increment block offloads counter. On failure,
3289 * previously offloaded filter is considered to be intact and offloads counter
3290 * is not decremented.
3291 */
3292
3293 int tc_setup_cb_add(struct tcf_block *block, struct tcf_proto *tp,
3294 enum tc_setup_type type, void *type_data, bool err_stop,
3295 u32 *flags, unsigned int *in_hw_count, bool rtnl_held)
3296 {
3297 bool take_rtnl = READ_ONCE(block->lockeddevcnt) && !rtnl_held;
3298 int ok_count;
3299
3300 retry:
3301 if (take_rtnl)
3302 rtnl_lock();
3303 down_read(&block->cb_lock);
3304 /* Need to obtain rtnl lock if block is bound to devs that require it.
3305 * In block bind code cb_lock is obtained while holding rtnl, so we must
3306 * obtain the locks in same order here.
3307 */
3308 if (!rtnl_held && !take_rtnl && block->lockeddevcnt) {
3309 up_read(&block->cb_lock);
3310 take_rtnl = true;
3311 goto retry;
3312 }
3313
3314 /* Make sure all netdevs sharing this block are offload-capable. */
3315 if (block->nooffloaddevcnt && err_stop) {
3316 ok_count = -EOPNOTSUPP;
3317 goto err_unlock;
3318 }
3319
3320 ok_count = __tc_setup_cb_call(block, type, type_data, err_stop);
3321 if (ok_count < 0)
3322 goto err_unlock;
3323
3324 if (tp->ops->hw_add)
3325 tp->ops->hw_add(tp, type_data);
3326 if (ok_count > 0)
3327 tc_cls_offload_cnt_update(block, tp, in_hw_count, flags,
3328 ok_count, true);
3329 err_unlock:
3330 up_read(&block->cb_lock);
3331 if (take_rtnl)
3332 rtnl_unlock();
3333 return ok_count < 0 ? ok_count : 0;
3334 }
3335 EXPORT_SYMBOL(tc_setup_cb_add);
3336
3337 /* Destructive filter replace. If filter that wasn't already in hardware is
3338 * successfully offloaded, increment block offload counter. On failure,
3339 * previously offloaded filter is considered to be destroyed and offload counter
3340 * is decremented.
3341 */
3342
3343 int tc_setup_cb_replace(struct tcf_block *block, struct tcf_proto *tp,
3344 enum tc_setup_type type, void *type_data, bool err_stop,
3345 u32 *old_flags, unsigned int *old_in_hw_count,
3346 u32 *new_flags, unsigned int *new_in_hw_count,
3347 bool rtnl_held)
3348 {
3349 bool take_rtnl = READ_ONCE(block->lockeddevcnt) && !rtnl_held;
3350 int ok_count;
3351
3352 retry:
3353 if (take_rtnl)
3354 rtnl_lock();
3355 down_read(&block->cb_lock);
3356 /* Need to obtain rtnl lock if block is bound to devs that require it.
3357 * In block bind code cb_lock is obtained while holding rtnl, so we must
3358 * obtain the locks in same order here.
3359 */
3360 if (!rtnl_held && !take_rtnl && block->lockeddevcnt) {
3361 up_read(&block->cb_lock);
3362 take_rtnl = true;
3363 goto retry;
3364 }
3365
3366 /* Make sure all netdevs sharing this block are offload-capable. */
3367 if (block->nooffloaddevcnt && err_stop) {
3368 ok_count = -EOPNOTSUPP;
3369 goto err_unlock;
3370 }
3371
3372 tc_cls_offload_cnt_reset(block, tp, old_in_hw_count, old_flags);
3373 if (tp->ops->hw_del)
3374 tp->ops->hw_del(tp, type_data);
3375
3376 ok_count = __tc_setup_cb_call(block, type, type_data, err_stop);
3377 if (ok_count < 0)
3378 goto err_unlock;
3379
3380 if (tp->ops->hw_add)
3381 tp->ops->hw_add(tp, type_data);
3382 if (ok_count > 0)
3383 tc_cls_offload_cnt_update(block, tp, new_in_hw_count,
3384 new_flags, ok_count, true);
3385 err_unlock:
3386 up_read(&block->cb_lock);
3387 if (take_rtnl)
3388 rtnl_unlock();
3389 return ok_count < 0 ? ok_count : 0;
3390 }
3391 EXPORT_SYMBOL(tc_setup_cb_replace);
3392
3393 /* Destroy filter and decrement block offload counter, if filter was previously
3394 * offloaded.
3395 */
3396
3397 int tc_setup_cb_destroy(struct tcf_block *block, struct tcf_proto *tp,
3398 enum tc_setup_type type, void *type_data, bool err_stop,
3399 u32 *flags, unsigned int *in_hw_count, bool rtnl_held)
3400 {
3401 bool take_rtnl = READ_ONCE(block->lockeddevcnt) && !rtnl_held;
3402 int ok_count;
3403
3404 retry:
3405 if (take_rtnl)
3406 rtnl_lock();
3407 down_read(&block->cb_lock);
3408 /* Need to obtain rtnl lock if block is bound to devs that require it.
3409 * In block bind code cb_lock is obtained while holding rtnl, so we must
3410 * obtain the locks in same order here.
3411 */
3412 if (!rtnl_held && !take_rtnl && block->lockeddevcnt) {
3413 up_read(&block->cb_lock);
3414 take_rtnl = true;
3415 goto retry;
3416 }
3417
3418 ok_count = __tc_setup_cb_call(block, type, type_data, err_stop);
3419
3420 tc_cls_offload_cnt_reset(block, tp, in_hw_count, flags);
3421 if (tp->ops->hw_del)
3422 tp->ops->hw_del(tp, type_data);
3423
3424 up_read(&block->cb_lock);
3425 if (take_rtnl)
3426 rtnl_unlock();
3427 return ok_count < 0 ? ok_count : 0;
3428 }
3429 EXPORT_SYMBOL(tc_setup_cb_destroy);
3430
3431 int tc_setup_cb_reoffload(struct tcf_block *block, struct tcf_proto *tp,
3432 bool add, flow_setup_cb_t *cb,
3433 enum tc_setup_type type, void *type_data,
3434 void *cb_priv, u32 *flags, unsigned int *in_hw_count)
3435 {
3436 int err = cb(type, type_data, cb_priv);
3437
3438 if (err) {
3439 if (add && tc_skip_sw(*flags))
3440 return err;
3441 } else {
3442 tc_cls_offload_cnt_update(block, tp, in_hw_count, flags, 1,
3443 add);
3444 }
3445
3446 return 0;
3447 }
3448 EXPORT_SYMBOL(tc_setup_cb_reoffload);
3449
3450 static int tcf_act_get_cookie(struct flow_action_entry *entry,
3451 const struct tc_action *act)
3452 {
3453 struct tc_cookie *cookie;
3454 int err = 0;
3455
3456 rcu_read_lock();
3457 cookie = rcu_dereference(act->act_cookie);
3458 if (cookie) {
3459 entry->cookie = flow_action_cookie_create(cookie->data,
3460 cookie->len,
3461 GFP_ATOMIC);
3462 if (!entry->cookie)
3463 err = -ENOMEM;
3464 }
3465 rcu_read_unlock();
3466 return err;
3467 }
3468
3469 static void tcf_act_put_cookie(struct flow_action_entry *entry)
3470 {
3471 flow_action_cookie_destroy(entry->cookie);
3472 }
3473
3474 void tc_cleanup_flow_action(struct flow_action *flow_action)
3475 {
3476 struct flow_action_entry *entry;
3477 int i;
3478
3479 flow_action_for_each(i, entry, flow_action) {
3480 tcf_act_put_cookie(entry);
3481 if (entry->destructor)
3482 entry->destructor(entry->destructor_priv);
3483 }
3484 }
3485 EXPORT_SYMBOL(tc_cleanup_flow_action);
3486
3487 static void tcf_mirred_get_dev(struct flow_action_entry *entry,
3488 const struct tc_action *act)
3489 {
3490 #ifdef CONFIG_NET_CLS_ACT
3491 entry->dev = act->ops->get_dev(act, &entry->destructor);
3492 if (!entry->dev)
3493 return;
3494 entry->destructor_priv = entry->dev;
3495 #endif
3496 }
3497
3498 static void tcf_tunnel_encap_put_tunnel(void *priv)
3499 {
3500 struct ip_tunnel_info *tunnel = priv;
3501
3502 kfree(tunnel);
3503 }
3504
3505 static int tcf_tunnel_encap_get_tunnel(struct flow_action_entry *entry,
3506 const struct tc_action *act)
3507 {
3508 entry->tunnel = tcf_tunnel_info_copy(act);
3509 if (!entry->tunnel)
3510 return -ENOMEM;
3511 entry->destructor = tcf_tunnel_encap_put_tunnel;
3512 entry->destructor_priv = entry->tunnel;
3513 return 0;
3514 }
3515
3516 static void tcf_sample_get_group(struct flow_action_entry *entry,
3517 const struct tc_action *act)
3518 {
3519 #ifdef CONFIG_NET_CLS_ACT
3520 entry->sample.psample_group =
3521 act->ops->get_psample_group(act, &entry->destructor);
3522 entry->destructor_priv = entry->sample.psample_group;
3523 #endif
3524 }
3525
3526 static enum flow_action_hw_stats tc_act_hw_stats(u8 hw_stats)
3527 {
3528 if (WARN_ON_ONCE(hw_stats > TCA_ACT_HW_STATS_ANY))
3529 return FLOW_ACTION_HW_STATS_DONT_CARE;
3530 else if (!hw_stats)
3531 return FLOW_ACTION_HW_STATS_DISABLED;
3532
3533 return hw_stats;
3534 }
3535
3536 int tc_setup_flow_action(struct flow_action *flow_action,
3537 const struct tcf_exts *exts)
3538 {
3539 struct tc_action *act;
3540 int i, j, k, err = 0;
3541
3542 BUILD_BUG_ON(TCA_ACT_HW_STATS_ANY != FLOW_ACTION_HW_STATS_ANY);
3543 BUILD_BUG_ON(TCA_ACT_HW_STATS_IMMEDIATE != FLOW_ACTION_HW_STATS_IMMEDIATE);
3544 BUILD_BUG_ON(TCA_ACT_HW_STATS_DELAYED != FLOW_ACTION_HW_STATS_DELAYED);
3545
3546 if (!exts)
3547 return 0;
3548
3549 j = 0;
3550 tcf_exts_for_each_action(i, act, exts) {
3551 struct flow_action_entry *entry;
3552
3553 entry = &flow_action->entries[j];
3554 spin_lock_bh(&act->tcfa_lock);
3555 err = tcf_act_get_cookie(entry, act);
3556 if (err)
3557 goto err_out_locked;
3558
3559 entry->hw_stats = tc_act_hw_stats(act->hw_stats);
3560
3561 if (is_tcf_gact_ok(act)) {
3562 entry->id = FLOW_ACTION_ACCEPT;
3563 } else if (is_tcf_gact_shot(act)) {
3564 entry->id = FLOW_ACTION_DROP;
3565 } else if (is_tcf_gact_trap(act)) {
3566 entry->id = FLOW_ACTION_TRAP;
3567 } else if (is_tcf_gact_goto_chain(act)) {
3568 entry->id = FLOW_ACTION_GOTO;
3569 entry->chain_index = tcf_gact_goto_chain_index(act);
3570 } else if (is_tcf_mirred_egress_redirect(act)) {
3571 entry->id = FLOW_ACTION_REDIRECT;
3572 tcf_mirred_get_dev(entry, act);
3573 } else if (is_tcf_mirred_egress_mirror(act)) {
3574 entry->id = FLOW_ACTION_MIRRED;
3575 tcf_mirred_get_dev(entry, act);
3576 } else if (is_tcf_mirred_ingress_redirect(act)) {
3577 entry->id = FLOW_ACTION_REDIRECT_INGRESS;
3578 tcf_mirred_get_dev(entry, act);
3579 } else if (is_tcf_mirred_ingress_mirror(act)) {
3580 entry->id = FLOW_ACTION_MIRRED_INGRESS;
3581 tcf_mirred_get_dev(entry, act);
3582 } else if (is_tcf_vlan(act)) {
3583 switch (tcf_vlan_action(act)) {
3584 case TCA_VLAN_ACT_PUSH:
3585 entry->id = FLOW_ACTION_VLAN_PUSH;
3586 entry->vlan.vid = tcf_vlan_push_vid(act);
3587 entry->vlan.proto = tcf_vlan_push_proto(act);
3588 entry->vlan.prio = tcf_vlan_push_prio(act);
3589 break;
3590 case TCA_VLAN_ACT_POP:
3591 entry->id = FLOW_ACTION_VLAN_POP;
3592 break;
3593 case TCA_VLAN_ACT_MODIFY:
3594 entry->id = FLOW_ACTION_VLAN_MANGLE;
3595 entry->vlan.vid = tcf_vlan_push_vid(act);
3596 entry->vlan.proto = tcf_vlan_push_proto(act);
3597 entry->vlan.prio = tcf_vlan_push_prio(act);
3598 break;
3599 default:
3600 err = -EOPNOTSUPP;
3601 goto err_out_locked;
3602 }
3603 } else if (is_tcf_tunnel_set(act)) {
3604 entry->id = FLOW_ACTION_TUNNEL_ENCAP;
3605 err = tcf_tunnel_encap_get_tunnel(entry, act);
3606 if (err)
3607 goto err_out_locked;
3608 } else if (is_tcf_tunnel_release(act)) {
3609 entry->id = FLOW_ACTION_TUNNEL_DECAP;
3610 } else if (is_tcf_pedit(act)) {
3611 for (k = 0; k < tcf_pedit_nkeys(act); k++) {
3612 switch (tcf_pedit_cmd(act, k)) {
3613 case TCA_PEDIT_KEY_EX_CMD_SET:
3614 entry->id = FLOW_ACTION_MANGLE;
3615 break;
3616 case TCA_PEDIT_KEY_EX_CMD_ADD:
3617 entry->id = FLOW_ACTION_ADD;
3618 break;
3619 default:
3620 err = -EOPNOTSUPP;
3621 goto err_out_locked;
3622 }
3623 entry->mangle.htype = tcf_pedit_htype(act, k);
3624 entry->mangle.mask = tcf_pedit_mask(act, k);
3625 entry->mangle.val = tcf_pedit_val(act, k);
3626 entry->mangle.offset = tcf_pedit_offset(act, k);
3627 entry->hw_stats = tc_act_hw_stats(act->hw_stats);
3628 entry = &flow_action->entries[++j];
3629 }
3630 } else if (is_tcf_csum(act)) {
3631 entry->id = FLOW_ACTION_CSUM;
3632 entry->csum_flags = tcf_csum_update_flags(act);
3633 } else if (is_tcf_skbedit_mark(act)) {
3634 entry->id = FLOW_ACTION_MARK;
3635 entry->mark = tcf_skbedit_mark(act);
3636 } else if (is_tcf_sample(act)) {
3637 entry->id = FLOW_ACTION_SAMPLE;
3638 entry->sample.trunc_size = tcf_sample_trunc_size(act);
3639 entry->sample.truncate = tcf_sample_truncate(act);
3640 entry->sample.rate = tcf_sample_rate(act);
3641 tcf_sample_get_group(entry, act);
3642 } else if (is_tcf_police(act)) {
3643 entry->id = FLOW_ACTION_POLICE;
3644 entry->police.burst = tcf_police_tcfp_burst(act);
3645 entry->police.rate_bytes_ps =
3646 tcf_police_rate_bytes_ps(act);
3647 } else if (is_tcf_ct(act)) {
3648 entry->id = FLOW_ACTION_CT;
3649 entry->ct.action = tcf_ct_action(act);
3650 entry->ct.zone = tcf_ct_zone(act);
3651 entry->ct.flow_table = tcf_ct_ft(act);
3652 } else if (is_tcf_mpls(act)) {
3653 switch (tcf_mpls_action(act)) {
3654 case TCA_MPLS_ACT_PUSH:
3655 entry->id = FLOW_ACTION_MPLS_PUSH;
3656 entry->mpls_push.proto = tcf_mpls_proto(act);
3657 entry->mpls_push.label = tcf_mpls_label(act);
3658 entry->mpls_push.tc = tcf_mpls_tc(act);
3659 entry->mpls_push.bos = tcf_mpls_bos(act);
3660 entry->mpls_push.ttl = tcf_mpls_ttl(act);
3661 break;
3662 case TCA_MPLS_ACT_POP:
3663 entry->id = FLOW_ACTION_MPLS_POP;
3664 entry->mpls_pop.proto = tcf_mpls_proto(act);
3665 break;
3666 case TCA_MPLS_ACT_MODIFY:
3667 entry->id = FLOW_ACTION_MPLS_MANGLE;
3668 entry->mpls_mangle.label = tcf_mpls_label(act);
3669 entry->mpls_mangle.tc = tcf_mpls_tc(act);
3670 entry->mpls_mangle.bos = tcf_mpls_bos(act);
3671 entry->mpls_mangle.ttl = tcf_mpls_ttl(act);
3672 break;
3673 default:
3674 goto err_out_locked;
3675 }
3676 } else if (is_tcf_skbedit_ptype(act)) {
3677 entry->id = FLOW_ACTION_PTYPE;
3678 entry->ptype = tcf_skbedit_ptype(act);
3679 } else if (is_tcf_skbedit_priority(act)) {
3680 entry->id = FLOW_ACTION_PRIORITY;
3681 entry->priority = tcf_skbedit_priority(act);
3682 } else {
3683 err = -EOPNOTSUPP;
3684 goto err_out_locked;
3685 }
3686 spin_unlock_bh(&act->tcfa_lock);
3687
3688 if (!is_tcf_pedit(act))
3689 j++;
3690 }
3691
3692 err_out:
3693 if (err)
3694 tc_cleanup_flow_action(flow_action);
3695
3696 return err;
3697 err_out_locked:
3698 spin_unlock_bh(&act->tcfa_lock);
3699 goto err_out;
3700 }
3701 EXPORT_SYMBOL(tc_setup_flow_action);
3702
3703 unsigned int tcf_exts_num_actions(struct tcf_exts *exts)
3704 {
3705 unsigned int num_acts = 0;
3706 struct tc_action *act;
3707 int i;
3708
3709 tcf_exts_for_each_action(i, act, exts) {
3710 if (is_tcf_pedit(act))
3711 num_acts += tcf_pedit_nkeys(act);
3712 else
3713 num_acts++;
3714 }
3715 return num_acts;
3716 }
3717 EXPORT_SYMBOL(tcf_exts_num_actions);
3718
3719 static __net_init int tcf_net_init(struct net *net)
3720 {
3721 struct tcf_net *tn = net_generic(net, tcf_net_id);
3722
3723 spin_lock_init(&tn->idr_lock);
3724 idr_init(&tn->idr);
3725 return 0;
3726 }
3727
3728 static void __net_exit tcf_net_exit(struct net *net)
3729 {
3730 struct tcf_net *tn = net_generic(net, tcf_net_id);
3731
3732 idr_destroy(&tn->idr);
3733 }
3734
3735 static struct pernet_operations tcf_net_ops = {
3736 .init = tcf_net_init,
3737 .exit = tcf_net_exit,
3738 .id = &tcf_net_id,
3739 .size = sizeof(struct tcf_net),
3740 };
3741
3742 static struct flow_indr_block_entry block_entry = {
3743 .cb = tc_indr_block_get_and_cmd,
3744 .list = LIST_HEAD_INIT(block_entry.list),
3745 };
3746
3747 static int __init tc_filter_init(void)
3748 {
3749 int err;
3750
3751 tc_filter_wq = alloc_ordered_workqueue("tc_filter_workqueue", 0);
3752 if (!tc_filter_wq)
3753 return -ENOMEM;
3754
3755 err = register_pernet_subsys(&tcf_net_ops);
3756 if (err)
3757 goto err_register_pernet_subsys;
3758
3759 flow_indr_add_block_cb(&block_entry);
3760
3761 rtnl_register(PF_UNSPEC, RTM_NEWTFILTER, tc_new_tfilter, NULL,
3762 RTNL_FLAG_DOIT_UNLOCKED);
3763 rtnl_register(PF_UNSPEC, RTM_DELTFILTER, tc_del_tfilter, NULL,
3764 RTNL_FLAG_DOIT_UNLOCKED);
3765 rtnl_register(PF_UNSPEC, RTM_GETTFILTER, tc_get_tfilter,
3766 tc_dump_tfilter, RTNL_FLAG_DOIT_UNLOCKED);
3767 rtnl_register(PF_UNSPEC, RTM_NEWCHAIN, tc_ctl_chain, NULL, 0);
3768 rtnl_register(PF_UNSPEC, RTM_DELCHAIN, tc_ctl_chain, NULL, 0);
3769 rtnl_register(PF_UNSPEC, RTM_GETCHAIN, tc_ctl_chain,
3770 tc_dump_chain, 0);
3771
3772 return 0;
3773
3774 err_register_pernet_subsys:
3775 destroy_workqueue(tc_filter_wq);
3776 return err;
3777 }
3778
3779 subsys_initcall(tc_filter_init);
Linux with added FPC-III support