xref: /openbmc/linux/net/sched/cls_api.c (revision f3539c12d8196ce0a1993364d30b3a18908470d1)
1 /*
2  * net/sched/cls_api.c	Packet classifier API.
3  *
4  *		This program is free software; you can redistribute it and/or
5  *		modify it under the terms of the GNU General Public License
6  *		as published by the Free Software Foundation; either version
7  *		2 of the License, or (at your option) any later version.
8  *
9  * Authors:	Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
10  *
11  * Changes:
12  *
13  * Eduardo J. Blanco <ejbs@netlabs.com.uy> :990222: kmod support
14  *
15  */
16 
17 #include <linux/module.h>
18 #include <linux/types.h>
19 #include <linux/kernel.h>
20 #include <linux/string.h>
21 #include <linux/errno.h>
22 #include <linux/skbuff.h>
23 #include <linux/init.h>
24 #include <linux/kmod.h>
25 #include <linux/err.h>
26 #include <linux/slab.h>
27 #include <net/net_namespace.h>
28 #include <net/sock.h>
29 #include <net/netlink.h>
30 #include <net/pkt_sched.h>
31 #include <net/pkt_cls.h>
32 
33 /* The list of all installed classifier types */
34 static LIST_HEAD(tcf_proto_base);
35 
36 /* Protects list of registered TC modules. It is pure SMP lock. */
37 static DEFINE_RWLOCK(cls_mod_lock);
38 
39 /* Find classifier type by string name */
40 
41 static const struct tcf_proto_ops *tcf_proto_lookup_ops(struct nlattr *kind)
42 {
43 	const struct tcf_proto_ops *t, *res = NULL;
44 
45 	if (kind) {
46 		read_lock(&cls_mod_lock);
47 		list_for_each_entry(t, &tcf_proto_base, head) {
48 			if (nla_strcmp(kind, t->kind) == 0) {
49 				if (try_module_get(t->owner))
50 					res = t;
51 				break;
52 			}
53 		}
54 		read_unlock(&cls_mod_lock);
55 	}
56 	return res;
57 }
58 
59 /* Register(unregister) new classifier type */
60 
61 int register_tcf_proto_ops(struct tcf_proto_ops *ops)
62 {
63 	struct tcf_proto_ops *t;
64 	int rc = -EEXIST;
65 
66 	write_lock(&cls_mod_lock);
67 	list_for_each_entry(t, &tcf_proto_base, head)
68 		if (!strcmp(ops->kind, t->kind))
69 			goto out;
70 
71 	list_add_tail(&ops->head, &tcf_proto_base);
72 	rc = 0;
73 out:
74 	write_unlock(&cls_mod_lock);
75 	return rc;
76 }
77 EXPORT_SYMBOL(register_tcf_proto_ops);
78 
79 int unregister_tcf_proto_ops(struct tcf_proto_ops *ops)
80 {
81 	struct tcf_proto_ops *t;
82 	int rc = -ENOENT;
83 
84 	/* Wait for outstanding call_rcu()s, if any, from a
85 	 * tcf_proto_ops's destroy() handler.
86 	 */
87 	rcu_barrier();
88 
89 	write_lock(&cls_mod_lock);
90 	list_for_each_entry(t, &tcf_proto_base, head) {
91 		if (t == ops) {
92 			list_del(&t->head);
93 			rc = 0;
94 			break;
95 		}
96 	}
97 	write_unlock(&cls_mod_lock);
98 	return rc;
99 }
100 EXPORT_SYMBOL(unregister_tcf_proto_ops);
101 
102 static int tfilter_notify(struct net *net, struct sk_buff *oskb,
103 			  struct nlmsghdr *n, struct tcf_proto *tp,
104 			  unsigned long fh, int event);
105 
106 static void tfilter_notify_chain(struct net *net, struct sk_buff *oskb,
107 				 struct nlmsghdr *n,
108 				 struct tcf_proto __rcu **chain, int event)
109 {
110 	struct tcf_proto __rcu **it_chain;
111 	struct tcf_proto *tp;
112 
113 	for (it_chain = chain; (tp = rtnl_dereference(*it_chain)) != NULL;
114 	     it_chain = &tp->next)
115 		tfilter_notify(net, oskb, n, tp, 0, event);
116 }
117 
118 /* Select new prio value from the range, managed by kernel. */
119 
120 static inline u32 tcf_auto_prio(struct tcf_proto *tp)
121 {
122 	u32 first = TC_H_MAKE(0xC0000000U, 0U);
123 
124 	if (tp)
125 		first = tp->prio - 1;
126 
127 	return first;
128 }
129 
130 /* Add/change/delete/get a filter node */
131 
132 static int tc_ctl_tfilter(struct sk_buff *skb, struct nlmsghdr *n)
133 {
134 	struct net *net = sock_net(skb->sk);
135 	struct nlattr *tca[TCA_MAX + 1];
136 	struct tcmsg *t;
137 	u32 protocol;
138 	u32 prio;
139 	u32 nprio;
140 	u32 parent;
141 	struct net_device *dev;
142 	struct Qdisc  *q;
143 	struct tcf_proto __rcu **back;
144 	struct tcf_proto __rcu **chain;
145 	struct tcf_proto *tp;
146 	const struct tcf_proto_ops *tp_ops;
147 	const struct Qdisc_class_ops *cops;
148 	unsigned long cl;
149 	unsigned long fh;
150 	int err;
151 	int tp_created = 0;
152 
153 	if ((n->nlmsg_type != RTM_GETTFILTER) &&
154 	    !netlink_ns_capable(skb, net->user_ns, CAP_NET_ADMIN))
155 		return -EPERM;
156 
157 replay:
158 	err = nlmsg_parse(n, sizeof(*t), tca, TCA_MAX, NULL);
159 	if (err < 0)
160 		return err;
161 
162 	t = nlmsg_data(n);
163 	protocol = TC_H_MIN(t->tcm_info);
164 	prio = TC_H_MAJ(t->tcm_info);
165 	nprio = prio;
166 	parent = t->tcm_parent;
167 	cl = 0;
168 
169 	if (prio == 0) {
170 		switch (n->nlmsg_type) {
171 		case RTM_DELTFILTER:
172 			if (protocol || t->tcm_handle || tca[TCA_KIND])
173 				return -ENOENT;
174 			break;
175 		case RTM_NEWTFILTER:
176 			/* If no priority is provided by the user,
177 			 * we allocate one.
178 			 */
179 			if (n->nlmsg_flags & NLM_F_CREATE) {
180 				prio = TC_H_MAKE(0x80000000U, 0U);
181 				break;
182 			}
183 			/* fall-through */
184 		default:
185 			return -ENOENT;
186 		}
187 	}
188 
189 	/* Find head of filter chain. */
190 
191 	/* Find link */
192 	dev = __dev_get_by_index(net, t->tcm_ifindex);
193 	if (dev == NULL)
194 		return -ENODEV;
195 
196 	/* Find qdisc */
197 	if (!parent) {
198 		q = dev->qdisc;
199 		parent = q->handle;
200 	} else {
201 		q = qdisc_lookup(dev, TC_H_MAJ(t->tcm_parent));
202 		if (q == NULL)
203 			return -EINVAL;
204 	}
205 
206 	/* Is it classful? */
207 	cops = q->ops->cl_ops;
208 	if (!cops)
209 		return -EINVAL;
210 
211 	if (cops->tcf_chain == NULL)
212 		return -EOPNOTSUPP;
213 
214 	/* Do we search for filter, attached to class? */
215 	if (TC_H_MIN(parent)) {
216 		cl = cops->get(q, parent);
217 		if (cl == 0)
218 			return -ENOENT;
219 	}
220 
221 	/* And the last stroke */
222 	chain = cops->tcf_chain(q, cl);
223 	err = -EINVAL;
224 	if (chain == NULL)
225 		goto errout;
226 	if (n->nlmsg_type == RTM_DELTFILTER && prio == 0) {
227 		tfilter_notify_chain(net, skb, n, chain, RTM_DELTFILTER);
228 		tcf_destroy_chain(chain);
229 		err = 0;
230 		goto errout;
231 	}
232 
233 	/* Check the chain for existence of proto-tcf with this priority */
234 	for (back = chain;
235 	     (tp = rtnl_dereference(*back)) != NULL;
236 	     back = &tp->next) {
237 		if (tp->prio >= prio) {
238 			if (tp->prio == prio) {
239 				if (!nprio ||
240 				    (tp->protocol != protocol && protocol))
241 					goto errout;
242 			} else
243 				tp = NULL;
244 			break;
245 		}
246 	}
247 
248 	if (tp == NULL) {
249 		/* Proto-tcf does not exist, create new one */
250 
251 		if (tca[TCA_KIND] == NULL || !protocol)
252 			goto errout;
253 
254 		err = -ENOENT;
255 		if (n->nlmsg_type != RTM_NEWTFILTER ||
256 		    !(n->nlmsg_flags & NLM_F_CREATE))
257 			goto errout;
258 
259 
260 		/* Create new proto tcf */
261 
262 		err = -ENOBUFS;
263 		tp = kzalloc(sizeof(*tp), GFP_KERNEL);
264 		if (tp == NULL)
265 			goto errout;
266 		err = -ENOENT;
267 		tp_ops = tcf_proto_lookup_ops(tca[TCA_KIND]);
268 		if (tp_ops == NULL) {
269 #ifdef CONFIG_MODULES
270 			struct nlattr *kind = tca[TCA_KIND];
271 			char name[IFNAMSIZ];
272 
273 			if (kind != NULL &&
274 			    nla_strlcpy(name, kind, IFNAMSIZ) < IFNAMSIZ) {
275 				rtnl_unlock();
276 				request_module("cls_%s", name);
277 				rtnl_lock();
278 				tp_ops = tcf_proto_lookup_ops(kind);
279 				/* We dropped the RTNL semaphore in order to
280 				 * perform the module load.  So, even if we
281 				 * succeeded in loading the module we have to
282 				 * replay the request.  We indicate this using
283 				 * -EAGAIN.
284 				 */
285 				if (tp_ops != NULL) {
286 					module_put(tp_ops->owner);
287 					err = -EAGAIN;
288 				}
289 			}
290 #endif
291 			kfree(tp);
292 			goto errout;
293 		}
294 		tp->ops = tp_ops;
295 		tp->protocol = protocol;
296 		tp->prio = nprio ? :
297 			       TC_H_MAJ(tcf_auto_prio(rtnl_dereference(*back)));
298 		tp->q = q;
299 		tp->classify = tp_ops->classify;
300 		tp->classid = parent;
301 
302 		err = tp_ops->init(tp);
303 		if (err != 0) {
304 			module_put(tp_ops->owner);
305 			kfree(tp);
306 			goto errout;
307 		}
308 
309 		tp_created = 1;
310 
311 	} else if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], tp->ops->kind))
312 		goto errout;
313 
314 	fh = tp->ops->get(tp, t->tcm_handle);
315 
316 	if (fh == 0) {
317 		if (n->nlmsg_type == RTM_DELTFILTER && t->tcm_handle == 0) {
318 			struct tcf_proto *next = rtnl_dereference(tp->next);
319 
320 			RCU_INIT_POINTER(*back, next);
321 
322 			tfilter_notify(net, skb, n, tp, fh, RTM_DELTFILTER);
323 			tcf_destroy(tp, true);
324 			err = 0;
325 			goto errout;
326 		}
327 
328 		err = -ENOENT;
329 		if (n->nlmsg_type != RTM_NEWTFILTER ||
330 		    !(n->nlmsg_flags & NLM_F_CREATE))
331 			goto errout;
332 	} else {
333 		switch (n->nlmsg_type) {
334 		case RTM_NEWTFILTER:
335 			err = -EEXIST;
336 			if (n->nlmsg_flags & NLM_F_EXCL) {
337 				if (tp_created)
338 					tcf_destroy(tp, true);
339 				goto errout;
340 			}
341 			break;
342 		case RTM_DELTFILTER:
343 			err = tp->ops->delete(tp, fh);
344 			if (err == 0) {
345 				struct tcf_proto *next = rtnl_dereference(tp->next);
346 
347 				tfilter_notify(net, skb, n, tp, fh, RTM_DELTFILTER);
348 				if (tcf_destroy(tp, false))
349 					RCU_INIT_POINTER(*back, next);
350 			}
351 			goto errout;
352 		case RTM_GETTFILTER:
353 			err = tfilter_notify(net, skb, n, tp, fh, RTM_NEWTFILTER);
354 			goto errout;
355 		default:
356 			err = -EINVAL;
357 			goto errout;
358 		}
359 	}
360 
361 	err = tp->ops->change(net, skb, tp, cl, t->tcm_handle, tca, &fh,
362 			      n->nlmsg_flags & NLM_F_CREATE ? TCA_ACT_NOREPLACE : TCA_ACT_REPLACE);
363 	if (err == 0) {
364 		if (tp_created) {
365 			RCU_INIT_POINTER(tp->next, rtnl_dereference(*back));
366 			rcu_assign_pointer(*back, tp);
367 		}
368 		tfilter_notify(net, skb, n, tp, fh, RTM_NEWTFILTER);
369 	} else {
370 		if (tp_created)
371 			tcf_destroy(tp, true);
372 	}
373 
374 errout:
375 	if (cl)
376 		cops->put(q, cl);
377 	if (err == -EAGAIN)
378 		/* Replay the request. */
379 		goto replay;
380 	return err;
381 }
382 
383 static int tcf_fill_node(struct net *net, struct sk_buff *skb,
384 			 struct tcf_proto *tp, unsigned long fh, u32 portid,
385 			 u32 seq, u16 flags, int event)
386 {
387 	struct tcmsg *tcm;
388 	struct nlmsghdr  *nlh;
389 	unsigned char *b = skb_tail_pointer(skb);
390 
391 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*tcm), flags);
392 	if (!nlh)
393 		goto out_nlmsg_trim;
394 	tcm = nlmsg_data(nlh);
395 	tcm->tcm_family = AF_UNSPEC;
396 	tcm->tcm__pad1 = 0;
397 	tcm->tcm__pad2 = 0;
398 	tcm->tcm_ifindex = qdisc_dev(tp->q)->ifindex;
399 	tcm->tcm_parent = tp->classid;
400 	tcm->tcm_info = TC_H_MAKE(tp->prio, tp->protocol);
401 	if (nla_put_string(skb, TCA_KIND, tp->ops->kind))
402 		goto nla_put_failure;
403 	tcm->tcm_handle = fh;
404 	if (RTM_DELTFILTER != event) {
405 		tcm->tcm_handle = 0;
406 		if (tp->ops->dump && tp->ops->dump(net, tp, fh, skb, tcm) < 0)
407 			goto nla_put_failure;
408 	}
409 	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
410 	return skb->len;
411 
412 out_nlmsg_trim:
413 nla_put_failure:
414 	nlmsg_trim(skb, b);
415 	return -1;
416 }
417 
418 static int tfilter_notify(struct net *net, struct sk_buff *oskb,
419 			  struct nlmsghdr *n, struct tcf_proto *tp,
420 			  unsigned long fh, int event)
421 {
422 	struct sk_buff *skb;
423 	u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
424 
425 	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
426 	if (!skb)
427 		return -ENOBUFS;
428 
429 	if (tcf_fill_node(net, skb, tp, fh, portid, n->nlmsg_seq, 0, event) <= 0) {
430 		kfree_skb(skb);
431 		return -EINVAL;
432 	}
433 
434 	return rtnetlink_send(skb, net, portid, RTNLGRP_TC,
435 			      n->nlmsg_flags & NLM_F_ECHO);
436 }
437 
438 struct tcf_dump_args {
439 	struct tcf_walker w;
440 	struct sk_buff *skb;
441 	struct netlink_callback *cb;
442 };
443 
444 static int tcf_node_dump(struct tcf_proto *tp, unsigned long n,
445 			 struct tcf_walker *arg)
446 {
447 	struct tcf_dump_args *a = (void *)arg;
448 	struct net *net = sock_net(a->skb->sk);
449 
450 	return tcf_fill_node(net, a->skb, tp, n, NETLINK_CB(a->cb->skb).portid,
451 			     a->cb->nlh->nlmsg_seq, NLM_F_MULTI, RTM_NEWTFILTER);
452 }
453 
454 /* called with RTNL */
455 static int tc_dump_tfilter(struct sk_buff *skb, struct netlink_callback *cb)
456 {
457 	struct net *net = sock_net(skb->sk);
458 	int t;
459 	int s_t;
460 	struct net_device *dev;
461 	struct Qdisc *q;
462 	struct tcf_proto *tp, __rcu **chain;
463 	struct tcmsg *tcm = nlmsg_data(cb->nlh);
464 	unsigned long cl = 0;
465 	const struct Qdisc_class_ops *cops;
466 	struct tcf_dump_args arg;
467 
468 	if (nlmsg_len(cb->nlh) < sizeof(*tcm))
469 		return skb->len;
470 	dev = __dev_get_by_index(net, tcm->tcm_ifindex);
471 	if (!dev)
472 		return skb->len;
473 
474 	if (!tcm->tcm_parent)
475 		q = dev->qdisc;
476 	else
477 		q = qdisc_lookup(dev, TC_H_MAJ(tcm->tcm_parent));
478 	if (!q)
479 		goto out;
480 	cops = q->ops->cl_ops;
481 	if (!cops)
482 		goto errout;
483 	if (cops->tcf_chain == NULL)
484 		goto errout;
485 	if (TC_H_MIN(tcm->tcm_parent)) {
486 		cl = cops->get(q, tcm->tcm_parent);
487 		if (cl == 0)
488 			goto errout;
489 	}
490 	chain = cops->tcf_chain(q, cl);
491 	if (chain == NULL)
492 		goto errout;
493 
494 	s_t = cb->args[0];
495 
496 	for (tp = rtnl_dereference(*chain), t = 0;
497 	     tp; tp = rtnl_dereference(tp->next), t++) {
498 		if (t < s_t)
499 			continue;
500 		if (TC_H_MAJ(tcm->tcm_info) &&
501 		    TC_H_MAJ(tcm->tcm_info) != tp->prio)
502 			continue;
503 		if (TC_H_MIN(tcm->tcm_info) &&
504 		    TC_H_MIN(tcm->tcm_info) != tp->protocol)
505 			continue;
506 		if (t > s_t)
507 			memset(&cb->args[1], 0,
508 			       sizeof(cb->args)-sizeof(cb->args[0]));
509 		if (cb->args[1] == 0) {
510 			if (tcf_fill_node(net, skb, tp, 0,
511 					  NETLINK_CB(cb->skb).portid,
512 					  cb->nlh->nlmsg_seq, NLM_F_MULTI,
513 					  RTM_NEWTFILTER) <= 0)
514 				break;
515 
516 			cb->args[1] = 1;
517 		}
518 		if (tp->ops->walk == NULL)
519 			continue;
520 		arg.w.fn = tcf_node_dump;
521 		arg.skb = skb;
522 		arg.cb = cb;
523 		arg.w.stop = 0;
524 		arg.w.skip = cb->args[1] - 1;
525 		arg.w.count = 0;
526 		tp->ops->walk(tp, &arg.w);
527 		cb->args[1] = arg.w.count + 1;
528 		if (arg.w.stop)
529 			break;
530 	}
531 
532 	cb->args[0] = t;
533 
534 errout:
535 	if (cl)
536 		cops->put(q, cl);
537 out:
538 	return skb->len;
539 }
540 
541 void tcf_exts_destroy(struct tcf_exts *exts)
542 {
543 #ifdef CONFIG_NET_CLS_ACT
544 	LIST_HEAD(actions);
545 
546 	tcf_exts_to_list(exts, &actions);
547 	tcf_action_destroy(&actions, TCA_ACT_UNBIND);
548 	kfree(exts->actions);
549 	exts->nr_actions = 0;
550 #endif
551 }
552 EXPORT_SYMBOL(tcf_exts_destroy);
553 
554 int tcf_exts_validate(struct net *net, struct tcf_proto *tp, struct nlattr **tb,
555 		  struct nlattr *rate_tlv, struct tcf_exts *exts, bool ovr)
556 {
557 #ifdef CONFIG_NET_CLS_ACT
558 	{
559 		struct tc_action *act;
560 
561 		if (exts->police && tb[exts->police]) {
562 			act = tcf_action_init_1(net, tb[exts->police], rate_tlv,
563 						"police", ovr,
564 						TCA_ACT_BIND);
565 			if (IS_ERR(act))
566 				return PTR_ERR(act);
567 
568 			act->type = exts->type = TCA_OLD_COMPAT;
569 			exts->actions[0] = act;
570 			exts->nr_actions = 1;
571 		} else if (exts->action && tb[exts->action]) {
572 			LIST_HEAD(actions);
573 			int err, i = 0;
574 
575 			err = tcf_action_init(net, tb[exts->action], rate_tlv,
576 					      NULL, ovr,
577 					      TCA_ACT_BIND, &actions);
578 			if (err)
579 				return err;
580 			list_for_each_entry(act, &actions, list)
581 				exts->actions[i++] = act;
582 			exts->nr_actions = i;
583 		}
584 	}
585 #else
586 	if ((exts->action && tb[exts->action]) ||
587 	    (exts->police && tb[exts->police]))
588 		return -EOPNOTSUPP;
589 #endif
590 
591 	return 0;
592 }
593 EXPORT_SYMBOL(tcf_exts_validate);
594 
595 void tcf_exts_change(struct tcf_proto *tp, struct tcf_exts *dst,
596 		     struct tcf_exts *src)
597 {
598 #ifdef CONFIG_NET_CLS_ACT
599 	struct tcf_exts old = *dst;
600 
601 	tcf_tree_lock(tp);
602 	dst->nr_actions = src->nr_actions;
603 	dst->actions = src->actions;
604 	dst->type = src->type;
605 	tcf_tree_unlock(tp);
606 
607 	tcf_exts_destroy(&old);
608 #endif
609 }
610 EXPORT_SYMBOL(tcf_exts_change);
611 
612 #ifdef CONFIG_NET_CLS_ACT
613 static struct tc_action *tcf_exts_first_act(struct tcf_exts *exts)
614 {
615 	if (exts->nr_actions == 0)
616 		return NULL;
617 	else
618 		return exts->actions[0];
619 }
620 #endif
621 
622 int tcf_exts_dump(struct sk_buff *skb, struct tcf_exts *exts)
623 {
624 #ifdef CONFIG_NET_CLS_ACT
625 	struct nlattr *nest;
626 
627 	if (exts->action && exts->nr_actions) {
628 		/*
629 		 * again for backward compatible mode - we want
630 		 * to work with both old and new modes of entering
631 		 * tc data even if iproute2  was newer - jhs
632 		 */
633 		if (exts->type != TCA_OLD_COMPAT) {
634 			LIST_HEAD(actions);
635 
636 			nest = nla_nest_start(skb, exts->action);
637 			if (nest == NULL)
638 				goto nla_put_failure;
639 
640 			tcf_exts_to_list(exts, &actions);
641 			if (tcf_action_dump(skb, &actions, 0, 0) < 0)
642 				goto nla_put_failure;
643 			nla_nest_end(skb, nest);
644 		} else if (exts->police) {
645 			struct tc_action *act = tcf_exts_first_act(exts);
646 			nest = nla_nest_start(skb, exts->police);
647 			if (nest == NULL || !act)
648 				goto nla_put_failure;
649 			if (tcf_action_dump_old(skb, act, 0, 0) < 0)
650 				goto nla_put_failure;
651 			nla_nest_end(skb, nest);
652 		}
653 	}
654 	return 0;
655 
656 nla_put_failure:
657 	nla_nest_cancel(skb, nest);
658 	return -1;
659 #else
660 	return 0;
661 #endif
662 }
663 EXPORT_SYMBOL(tcf_exts_dump);
664 
665 
666 int tcf_exts_dump_stats(struct sk_buff *skb, struct tcf_exts *exts)
667 {
668 #ifdef CONFIG_NET_CLS_ACT
669 	struct tc_action *a = tcf_exts_first_act(exts);
670 	if (a != NULL && tcf_action_copy_stats(skb, a, 1) < 0)
671 		return -1;
672 #endif
673 	return 0;
674 }
675 EXPORT_SYMBOL(tcf_exts_dump_stats);
676 
677 static int __init tc_filter_init(void)
678 {
679 	rtnl_register(PF_UNSPEC, RTM_NEWTFILTER, tc_ctl_tfilter, NULL, NULL);
680 	rtnl_register(PF_UNSPEC, RTM_DELTFILTER, tc_ctl_tfilter, NULL, NULL);
681 	rtnl_register(PF_UNSPEC, RTM_GETTFILTER, tc_ctl_tfilter,
682 		      tc_dump_tfilter, NULL);
683 
684 	return 0;
685 }
686 
687 subsys_initcall(tc_filter_init);
688