1
2
3
4
5
6
7
8
9
10
11
12
13
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
34static LIST_HEAD(tcf_proto_base);
35
36
37static DEFINE_RWLOCK(cls_mod_lock);
38
39
40
41static 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
60
61int 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;
73out:
74 write_unlock(&cls_mod_lock);
75 return rc;
76}
77EXPORT_SYMBOL(register_tcf_proto_ops);
78
79int unregister_tcf_proto_ops(struct tcf_proto_ops *ops)
80{
81 struct tcf_proto_ops *t;
82 int rc = -ENOENT;
83
84 write_lock(&cls_mod_lock);
85 list_for_each_entry(t, &tcf_proto_base, head) {
86 if (t == ops) {
87 list_del(&t->head);
88 rc = 0;
89 break;
90 }
91 }
92 write_unlock(&cls_mod_lock);
93 return rc;
94}
95EXPORT_SYMBOL(unregister_tcf_proto_ops);
96
97static int tfilter_notify(struct net *net, struct sk_buff *oskb,
98 struct nlmsghdr *n, struct tcf_proto *tp,
99 unsigned long fh, int event);
100
101
102
103
104static inline u32 tcf_auto_prio(struct tcf_proto *tp)
105{
106 u32 first = TC_H_MAKE(0xC0000000U, 0U);
107
108 if (tp)
109 first = tp->prio - 1;
110
111 return first;
112}
113
114
115
116static int tc_ctl_tfilter(struct sk_buff *skb, struct nlmsghdr *n)
117{
118 struct net *net = sock_net(skb->sk);
119 struct nlattr *tca[TCA_MAX + 1];
120 struct tcmsg *t;
121 u32 protocol;
122 u32 prio;
123 u32 nprio;
124 u32 parent;
125 struct net_device *dev;
126 struct Qdisc *q;
127 struct tcf_proto __rcu **back;
128 struct tcf_proto __rcu **chain;
129 struct tcf_proto *tp;
130 const struct tcf_proto_ops *tp_ops;
131 const struct Qdisc_class_ops *cops;
132 unsigned long cl;
133 unsigned long fh;
134 int err;
135 int tp_created = 0;
136
137 if ((n->nlmsg_type != RTM_GETTFILTER) &&
138 !netlink_ns_capable(skb, net->user_ns, CAP_NET_ADMIN))
139 return -EPERM;
140
141replay:
142 err = nlmsg_parse(n, sizeof(*t), tca, TCA_MAX, NULL);
143 if (err < 0)
144 return err;
145
146 t = nlmsg_data(n);
147 protocol = TC_H_MIN(t->tcm_info);
148 prio = TC_H_MAJ(t->tcm_info);
149 nprio = prio;
150 parent = t->tcm_parent;
151 cl = 0;
152
153 if (prio == 0) {
154
155 if (n->nlmsg_type != RTM_NEWTFILTER ||
156 !(n->nlmsg_flags & NLM_F_CREATE))
157 return -ENOENT;
158 prio = TC_H_MAKE(0x80000000U, 0U);
159 }
160
161
162
163
164 dev = __dev_get_by_index(net, t->tcm_ifindex);
165 if (dev == NULL)
166 return -ENODEV;
167
168
169 if (!parent) {
170 q = dev->qdisc;
171 parent = q->handle;
172 } else {
173 q = qdisc_lookup(dev, TC_H_MAJ(t->tcm_parent));
174 if (q == NULL)
175 return -EINVAL;
176 }
177
178
179 cops = q->ops->cl_ops;
180 if (!cops)
181 return -EINVAL;
182
183 if (cops->tcf_chain == NULL)
184 return -EOPNOTSUPP;
185
186
187 if (TC_H_MIN(parent)) {
188 cl = cops->get(q, parent);
189 if (cl == 0)
190 return -ENOENT;
191 }
192
193
194 chain = cops->tcf_chain(q, cl);
195 err = -EINVAL;
196 if (chain == NULL)
197 goto errout;
198
199
200 for (back = chain;
201 (tp = rtnl_dereference(*back)) != NULL;
202 back = &tp->next) {
203 if (tp->prio >= prio) {
204 if (tp->prio == prio) {
205 if (!nprio ||
206 (tp->protocol != protocol && protocol))
207 goto errout;
208 } else
209 tp = NULL;
210 break;
211 }
212 }
213
214 if (tp == NULL) {
215
216
217 if (tca[TCA_KIND] == NULL || !protocol)
218 goto errout;
219
220 err = -ENOENT;
221 if (n->nlmsg_type != RTM_NEWTFILTER ||
222 !(n->nlmsg_flags & NLM_F_CREATE))
223 goto errout;
224
225
226
227
228 err = -ENOBUFS;
229 tp = kzalloc(sizeof(*tp), GFP_KERNEL);
230 if (tp == NULL)
231 goto errout;
232 err = -ENOENT;
233 tp_ops = tcf_proto_lookup_ops(tca[TCA_KIND]);
234 if (tp_ops == NULL) {
235#ifdef CONFIG_MODULES
236 struct nlattr *kind = tca[TCA_KIND];
237 char name[IFNAMSIZ];
238
239 if (kind != NULL &&
240 nla_strlcpy(name, kind, IFNAMSIZ) < IFNAMSIZ) {
241 rtnl_unlock();
242 request_module("cls_%s", name);
243 rtnl_lock();
244 tp_ops = tcf_proto_lookup_ops(kind);
245
246
247
248
249
250
251 if (tp_ops != NULL) {
252 module_put(tp_ops->owner);
253 err = -EAGAIN;
254 }
255 }
256#endif
257 kfree(tp);
258 goto errout;
259 }
260 tp->ops = tp_ops;
261 tp->protocol = protocol;
262 tp->prio = nprio ? :
263 TC_H_MAJ(tcf_auto_prio(rtnl_dereference(*back)));
264 tp->q = q;
265 tp->classify = tp_ops->classify;
266 tp->classid = parent;
267
268 err = tp_ops->init(tp);
269 if (err != 0) {
270 module_put(tp_ops->owner);
271 kfree(tp);
272 goto errout;
273 }
274
275 tp_created = 1;
276
277 } else if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], tp->ops->kind))
278 goto errout;
279
280 fh = tp->ops->get(tp, t->tcm_handle);
281
282 if (fh == 0) {
283 if (n->nlmsg_type == RTM_DELTFILTER && t->tcm_handle == 0) {
284 struct tcf_proto *next = rtnl_dereference(tp->next);
285
286 RCU_INIT_POINTER(*back, next);
287
288 tfilter_notify(net, skb, n, tp, fh, RTM_DELTFILTER);
289 tcf_destroy(tp);
290 err = 0;
291 goto errout;
292 }
293
294 err = -ENOENT;
295 if (n->nlmsg_type != RTM_NEWTFILTER ||
296 !(n->nlmsg_flags & NLM_F_CREATE))
297 goto errout;
298 } else {
299 switch (n->nlmsg_type) {
300 case RTM_NEWTFILTER:
301 err = -EEXIST;
302 if (n->nlmsg_flags & NLM_F_EXCL) {
303 if (tp_created)
304 tcf_destroy(tp);
305 goto errout;
306 }
307 break;
308 case RTM_DELTFILTER:
309 err = tp->ops->delete(tp, fh);
310 if (err == 0)
311 tfilter_notify(net, skb, n, tp, fh, RTM_DELTFILTER);
312 goto errout;
313 case RTM_GETTFILTER:
314 err = tfilter_notify(net, skb, n, tp, fh, RTM_NEWTFILTER);
315 goto errout;
316 default:
317 err = -EINVAL;
318 goto errout;
319 }
320 }
321
322 err = tp->ops->change(net, skb, tp, cl, t->tcm_handle, tca, &fh,
323 n->nlmsg_flags & NLM_F_CREATE ? TCA_ACT_NOREPLACE : TCA_ACT_REPLACE);
324 if (err == 0) {
325 if (tp_created) {
326 RCU_INIT_POINTER(tp->next, rtnl_dereference(*back));
327 rcu_assign_pointer(*back, tp);
328 }
329 tfilter_notify(net, skb, n, tp, fh, RTM_NEWTFILTER);
330 } else {
331 if (tp_created)
332 tcf_destroy(tp);
333 }
334
335errout:
336 if (cl)
337 cops->put(q, cl);
338 if (err == -EAGAIN)
339
340 goto replay;
341 return err;
342}
343
344static int tcf_fill_node(struct net *net, struct sk_buff *skb, struct tcf_proto *tp,
345 unsigned long fh, u32 portid, u32 seq, u16 flags, int event)
346{
347 struct tcmsg *tcm;
348 struct nlmsghdr *nlh;
349 unsigned char *b = skb_tail_pointer(skb);
350
351 nlh = nlmsg_put(skb, portid, seq, event, sizeof(*tcm), flags);
352 if (!nlh)
353 goto out_nlmsg_trim;
354 tcm = nlmsg_data(nlh);
355 tcm->tcm_family = AF_UNSPEC;
356 tcm->tcm__pad1 = 0;
357 tcm->tcm__pad2 = 0;
358 tcm->tcm_ifindex = qdisc_dev(tp->q)->ifindex;
359 tcm->tcm_parent = tp->classid;
360 tcm->tcm_info = TC_H_MAKE(tp->prio, tp->protocol);
361 if (nla_put_string(skb, TCA_KIND, tp->ops->kind))
362 goto nla_put_failure;
363 tcm->tcm_handle = fh;
364 if (RTM_DELTFILTER != event) {
365 tcm->tcm_handle = 0;
366 if (tp->ops->dump && tp->ops->dump(net, tp, fh, skb, tcm) < 0)
367 goto nla_put_failure;
368 }
369 nlh->nlmsg_len = skb_tail_pointer(skb) - b;
370 return skb->len;
371
372out_nlmsg_trim:
373nla_put_failure:
374 nlmsg_trim(skb, b);
375 return -1;
376}
377
378static int tfilter_notify(struct net *net, struct sk_buff *oskb,
379 struct nlmsghdr *n, struct tcf_proto *tp,
380 unsigned long fh, int event)
381{
382 struct sk_buff *skb;
383 u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
384
385 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
386 if (!skb)
387 return -ENOBUFS;
388
389 if (tcf_fill_node(net, skb, tp, fh, portid, n->nlmsg_seq, 0, event) <= 0) {
390 kfree_skb(skb);
391 return -EINVAL;
392 }
393
394 return rtnetlink_send(skb, net, portid, RTNLGRP_TC,
395 n->nlmsg_flags & NLM_F_ECHO);
396}
397
398struct tcf_dump_args {
399 struct tcf_walker w;
400 struct sk_buff *skb;
401 struct netlink_callback *cb;
402};
403
404static int tcf_node_dump(struct tcf_proto *tp, unsigned long n,
405 struct tcf_walker *arg)
406{
407 struct tcf_dump_args *a = (void *)arg;
408 struct net *net = sock_net(a->skb->sk);
409
410 return tcf_fill_node(net, a->skb, tp, n, NETLINK_CB(a->cb->skb).portid,
411 a->cb->nlh->nlmsg_seq, NLM_F_MULTI, RTM_NEWTFILTER);
412}
413
414
415static int tc_dump_tfilter(struct sk_buff *skb, struct netlink_callback *cb)
416{
417 struct net *net = sock_net(skb->sk);
418 int t;
419 int s_t;
420 struct net_device *dev;
421 struct Qdisc *q;
422 struct tcf_proto *tp, __rcu **chain;
423 struct tcmsg *tcm = nlmsg_data(cb->nlh);
424 unsigned long cl = 0;
425 const struct Qdisc_class_ops *cops;
426 struct tcf_dump_args arg;
427
428 if (nlmsg_len(cb->nlh) < sizeof(*tcm))
429 return skb->len;
430 dev = __dev_get_by_index(net, tcm->tcm_ifindex);
431 if (!dev)
432 return skb->len;
433
434 if (!tcm->tcm_parent)
435 q = dev->qdisc;
436 else
437 q = qdisc_lookup(dev, TC_H_MAJ(tcm->tcm_parent));
438 if (!q)
439 goto out;
440 cops = q->ops->cl_ops;
441 if (!cops)
442 goto errout;
443 if (cops->tcf_chain == NULL)
444 goto errout;
445 if (TC_H_MIN(tcm->tcm_parent)) {
446 cl = cops->get(q, tcm->tcm_parent);
447 if (cl == 0)
448 goto errout;
449 }
450 chain = cops->tcf_chain(q, cl);
451 if (chain == NULL)
452 goto errout;
453
454 s_t = cb->args[0];
455
456 for (tp = rtnl_dereference(*chain), t = 0;
457 tp; tp = rtnl_dereference(tp->next), t++) {
458 if (t < s_t)
459 continue;
460 if (TC_H_MAJ(tcm->tcm_info) &&
461 TC_H_MAJ(tcm->tcm_info) != tp->prio)
462 continue;
463 if (TC_H_MIN(tcm->tcm_info) &&
464 TC_H_MIN(tcm->tcm_info) != tp->protocol)
465 continue;
466 if (t > s_t)
467 memset(&cb->args[1], 0, sizeof(cb->args)-sizeof(cb->args[0]));
468 if (cb->args[1] == 0) {
469 if (tcf_fill_node(net, skb, tp, 0, NETLINK_CB(cb->skb).portid,
470 cb->nlh->nlmsg_seq, NLM_F_MULTI,
471 RTM_NEWTFILTER) <= 0)
472 break;
473
474 cb->args[1] = 1;
475 }
476 if (tp->ops->walk == NULL)
477 continue;
478 arg.w.fn = tcf_node_dump;
479 arg.skb = skb;
480 arg.cb = cb;
481 arg.w.stop = 0;
482 arg.w.skip = cb->args[1] - 1;
483 arg.w.count = 0;
484 tp->ops->walk(tp, &arg.w);
485 cb->args[1] = arg.w.count + 1;
486 if (arg.w.stop)
487 break;
488 }
489
490 cb->args[0] = t;
491
492errout:
493 if (cl)
494 cops->put(q, cl);
495out:
496 return skb->len;
497}
498
499void tcf_exts_destroy(struct tcf_exts *exts)
500{
501#ifdef CONFIG_NET_CLS_ACT
502 tcf_action_destroy(&exts->actions, TCA_ACT_UNBIND);
503 INIT_LIST_HEAD(&exts->actions);
504#endif
505}
506EXPORT_SYMBOL(tcf_exts_destroy);
507
508int tcf_exts_validate(struct net *net, struct tcf_proto *tp, struct nlattr **tb,
509 struct nlattr *rate_tlv, struct tcf_exts *exts, bool ovr)
510{
511#ifdef CONFIG_NET_CLS_ACT
512 {
513 struct tc_action *act;
514
515 INIT_LIST_HEAD(&exts->actions);
516 if (exts->police && tb[exts->police]) {
517 act = tcf_action_init_1(net, tb[exts->police], rate_tlv,
518 "police", ovr,
519 TCA_ACT_BIND);
520 if (IS_ERR(act))
521 return PTR_ERR(act);
522
523 act->type = exts->type = TCA_OLD_COMPAT;
524 list_add(&act->list, &exts->actions);
525 } else if (exts->action && tb[exts->action]) {
526 int err;
527 err = tcf_action_init(net, tb[exts->action], rate_tlv,
528 NULL, ovr,
529 TCA_ACT_BIND, &exts->actions);
530 if (err)
531 return err;
532 }
533 }
534#else
535 if ((exts->action && tb[exts->action]) ||
536 (exts->police && tb[exts->police]))
537 return -EOPNOTSUPP;
538#endif
539
540 return 0;
541}
542EXPORT_SYMBOL(tcf_exts_validate);
543
544void tcf_exts_change(struct tcf_proto *tp, struct tcf_exts *dst,
545 struct tcf_exts *src)
546{
547#ifdef CONFIG_NET_CLS_ACT
548 LIST_HEAD(tmp);
549 tcf_tree_lock(tp);
550 list_splice_init(&dst->actions, &tmp);
551 list_splice(&src->actions, &dst->actions);
552 dst->type = src->type;
553 tcf_tree_unlock(tp);
554 tcf_action_destroy(&tmp, TCA_ACT_UNBIND);
555#endif
556}
557EXPORT_SYMBOL(tcf_exts_change);
558
559#define tcf_exts_first_act(ext) \
560 list_first_entry_or_null(&(exts)->actions, \
561 struct tc_action, list)
562
563int tcf_exts_dump(struct sk_buff *skb, struct tcf_exts *exts)
564{
565#ifdef CONFIG_NET_CLS_ACT
566 struct nlattr *nest;
567
568 if (exts->action && !list_empty(&exts->actions)) {
569
570
571
572
573
574 if (exts->type != TCA_OLD_COMPAT) {
575 nest = nla_nest_start(skb, exts->action);
576 if (nest == NULL)
577 goto nla_put_failure;
578 if (tcf_action_dump(skb, &exts->actions, 0, 0) < 0)
579 goto nla_put_failure;
580 nla_nest_end(skb, nest);
581 } else if (exts->police) {
582 struct tc_action *act = tcf_exts_first_act(exts);
583 nest = nla_nest_start(skb, exts->police);
584 if (nest == NULL || !act)
585 goto nla_put_failure;
586 if (tcf_action_dump_old(skb, act, 0, 0) < 0)
587 goto nla_put_failure;
588 nla_nest_end(skb, nest);
589 }
590 }
591 return 0;
592
593nla_put_failure:
594 nla_nest_cancel(skb, nest);
595 return -1;
596#else
597 return 0;
598#endif
599}
600EXPORT_SYMBOL(tcf_exts_dump);
601
602
603int tcf_exts_dump_stats(struct sk_buff *skb, struct tcf_exts *exts)
604{
605#ifdef CONFIG_NET_CLS_ACT
606 struct tc_action *a = tcf_exts_first_act(exts);
607 if (a != NULL && tcf_action_copy_stats(skb, a, 1) < 0)
608 return -1;
609#endif
610 return 0;
611}
612EXPORT_SYMBOL(tcf_exts_dump_stats);
613
614static int __init tc_filter_init(void)
615{
616 rtnl_register(PF_UNSPEC, RTM_NEWTFILTER, tc_ctl_tfilter, NULL, NULL);
617 rtnl_register(PF_UNSPEC, RTM_DELTFILTER, tc_ctl_tfilter, NULL, NULL);
618 rtnl_register(PF_UNSPEC, RTM_GETTFILTER, tc_ctl_tfilter,
619 tc_dump_tfilter, NULL);
620
621 return 0;
622}
623
624subsys_initcall(tc_filter_init);
625
