blob: 03657976fd501f9715840750e51bf9029f1c631d [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
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
Linus Torvalds1da177e2005-04-16 15:20:36 -070017#include <linux/module.h>
18#include <linux/types.h>
19#include <linux/kernel.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070020#include <linux/string.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070021#include <linux/errno.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070022#include <linux/skbuff.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070023#include <linux/init.h>
24#include <linux/kmod.h>
Arnaldo Carvalho de Melodc5fc572007-03-25 23:06:12 -070025#include <linux/netlink.h>
26#include <net/netlink.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070027#include <net/pkt_sched.h>
28#include <net/pkt_cls.h>
29
30#if 0 /* control */
31#define DPRINTK(format,args...) printk(KERN_DEBUG format,##args)
32#else
33#define DPRINTK(format,args...)
34#endif
35
36/* The list of all installed classifier types */
37
38static struct tcf_proto_ops *tcf_proto_base;
39
40/* Protects list of registered TC modules. It is pure SMP lock. */
41static DEFINE_RWLOCK(cls_mod_lock);
42
43/* Find classifier type by string name */
44
45static struct tcf_proto_ops * tcf_proto_lookup_ops(struct rtattr *kind)
46{
47 struct tcf_proto_ops *t = NULL;
48
49 if (kind) {
50 read_lock(&cls_mod_lock);
51 for (t = tcf_proto_base; t; t = t->next) {
52 if (rtattr_strcmp(kind, t->kind) == 0) {
53 if (!try_module_get(t->owner))
54 t = NULL;
55 break;
56 }
57 }
58 read_unlock(&cls_mod_lock);
59 }
60 return t;
61}
62
63/* Register(unregister) new classifier type */
64
65int register_tcf_proto_ops(struct tcf_proto_ops *ops)
66{
67 struct tcf_proto_ops *t, **tp;
68 int rc = -EEXIST;
69
70 write_lock(&cls_mod_lock);
71 for (tp = &tcf_proto_base; (t = *tp) != NULL; tp = &t->next)
72 if (!strcmp(ops->kind, t->kind))
73 goto out;
74
75 ops->next = NULL;
76 *tp = ops;
77 rc = 0;
78out:
79 write_unlock(&cls_mod_lock);
80 return rc;
81}
82
83int unregister_tcf_proto_ops(struct tcf_proto_ops *ops)
84{
85 struct tcf_proto_ops *t, **tp;
86 int rc = -ENOENT;
87
88 write_lock(&cls_mod_lock);
89 for (tp = &tcf_proto_base; (t=*tp) != NULL; tp = &t->next)
90 if (t == ops)
91 break;
92
93 if (!t)
94 goto out;
95 *tp = t->next;
96 rc = 0;
97out:
98 write_unlock(&cls_mod_lock);
99 return rc;
100}
101
102static int tfilter_notify(struct sk_buff *oskb, struct nlmsghdr *n,
103 struct tcf_proto *tp, unsigned long fh, int event);
104
105
106/* Select new prio value from the range, managed by kernel. */
107
108static __inline__ u32 tcf_auto_prio(struct tcf_proto *tp)
109{
110 u32 first = TC_H_MAKE(0xC0000000U,0U);
111
112 if (tp)
113 first = tp->prio-1;
114
115 return first;
116}
117
118/* Add/change/delete/get a filter node */
119
120static int tc_ctl_tfilter(struct sk_buff *skb, struct nlmsghdr *n, void *arg)
121{
122 struct rtattr **tca;
123 struct tcmsg *t;
124 u32 protocol;
125 u32 prio;
126 u32 nprio;
127 u32 parent;
128 struct net_device *dev;
129 struct Qdisc *q;
130 struct tcf_proto **back, **chain;
131 struct tcf_proto *tp;
132 struct tcf_proto_ops *tp_ops;
133 struct Qdisc_class_ops *cops;
134 unsigned long cl;
135 unsigned long fh;
136 int err;
137
138replay:
139 tca = arg;
140 t = NLMSG_DATA(n);
141 protocol = TC_H_MIN(t->tcm_info);
142 prio = TC_H_MAJ(t->tcm_info);
143 nprio = prio;
144 parent = t->tcm_parent;
145 cl = 0;
146
147 if (prio == 0) {
148 /* If no priority is given, user wants we allocated it. */
149 if (n->nlmsg_type != RTM_NEWTFILTER || !(n->nlmsg_flags&NLM_F_CREATE))
150 return -ENOENT;
151 prio = TC_H_MAKE(0x80000000U,0U);
152 }
153
154 /* Find head of filter chain. */
155
156 /* Find link */
Eric W. Biederman881d9662007-09-17 11:56:21 -0700157 if ((dev = __dev_get_by_index(&init_net, t->tcm_ifindex)) == NULL)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700158 return -ENODEV;
159
160 /* Find qdisc */
161 if (!parent) {
162 q = dev->qdisc_sleeping;
163 parent = q->handle;
164 } else if ((q = qdisc_lookup(dev, TC_H_MAJ(t->tcm_parent))) == NULL)
165 return -EINVAL;
166
167 /* Is it classful? */
168 if ((cops = q->ops->cl_ops) == NULL)
169 return -EINVAL;
170
171 /* Do we search for filter, attached to class? */
172 if (TC_H_MIN(parent)) {
173 cl = cops->get(q, parent);
174 if (cl == 0)
175 return -ENOENT;
176 }
177
178 /* And the last stroke */
179 chain = cops->tcf_chain(q, cl);
180 err = -EINVAL;
181 if (chain == NULL)
182 goto errout;
183
184 /* Check the chain for existence of proto-tcf with this priority */
185 for (back = chain; (tp=*back) != NULL; back = &tp->next) {
186 if (tp->prio >= prio) {
187 if (tp->prio == prio) {
188 if (!nprio || (tp->protocol != protocol && protocol))
189 goto errout;
190 } else
191 tp = NULL;
192 break;
193 }
194 }
195
196 if (tp == NULL) {
197 /* Proto-tcf does not exist, create new one */
198
199 if (tca[TCA_KIND-1] == NULL || !protocol)
200 goto errout;
201
202 err = -ENOENT;
203 if (n->nlmsg_type != RTM_NEWTFILTER || !(n->nlmsg_flags&NLM_F_CREATE))
204 goto errout;
205
206
207 /* Create new proto tcf */
208
209 err = -ENOBUFS;
Arnaldo Carvalho de Meloc7b1b242006-11-21 01:19:40 -0200210 if ((tp = kzalloc(sizeof(*tp), GFP_KERNEL)) == NULL)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700211 goto errout;
212 err = -EINVAL;
213 tp_ops = tcf_proto_lookup_ops(tca[TCA_KIND-1]);
214 if (tp_ops == NULL) {
215#ifdef CONFIG_KMOD
216 struct rtattr *kind = tca[TCA_KIND-1];
217 char name[IFNAMSIZ];
218
219 if (kind != NULL &&
220 rtattr_strlcpy(name, kind, IFNAMSIZ) < IFNAMSIZ) {
221 rtnl_unlock();
222 request_module("cls_%s", name);
223 rtnl_lock();
224 tp_ops = tcf_proto_lookup_ops(kind);
225 /* We dropped the RTNL semaphore in order to
226 * perform the module load. So, even if we
227 * succeeded in loading the module we have to
228 * replay the request. We indicate this using
229 * -EAGAIN.
230 */
231 if (tp_ops != NULL) {
232 module_put(tp_ops->owner);
233 err = -EAGAIN;
234 }
235 }
236#endif
237 kfree(tp);
238 goto errout;
239 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700240 tp->ops = tp_ops;
241 tp->protocol = protocol;
242 tp->prio = nprio ? : tcf_auto_prio(*back);
243 tp->q = q;
244 tp->classify = tp_ops->classify;
245 tp->classid = parent;
246 if ((err = tp_ops->init(tp)) != 0) {
247 module_put(tp_ops->owner);
248 kfree(tp);
249 goto errout;
250 }
251
252 qdisc_lock_tree(dev);
253 tp->next = *back;
254 *back = tp;
255 qdisc_unlock_tree(dev);
256
257 } else if (tca[TCA_KIND-1] && rtattr_strcmp(tca[TCA_KIND-1], tp->ops->kind))
258 goto errout;
259
260 fh = tp->ops->get(tp, t->tcm_handle);
261
262 if (fh == 0) {
263 if (n->nlmsg_type == RTM_DELTFILTER && t->tcm_handle == 0) {
264 qdisc_lock_tree(dev);
265 *back = tp->next;
266 qdisc_unlock_tree(dev);
267
268 tfilter_notify(skb, n, tp, fh, RTM_DELTFILTER);
269 tcf_destroy(tp);
270 err = 0;
271 goto errout;
272 }
273
274 err = -ENOENT;
275 if (n->nlmsg_type != RTM_NEWTFILTER || !(n->nlmsg_flags&NLM_F_CREATE))
276 goto errout;
277 } else {
278 switch (n->nlmsg_type) {
YOSHIFUJI Hideaki10297b92007-02-09 23:25:16 +0900279 case RTM_NEWTFILTER:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700280 err = -EEXIST;
281 if (n->nlmsg_flags&NLM_F_EXCL)
282 goto errout;
283 break;
284 case RTM_DELTFILTER:
285 err = tp->ops->delete(tp, fh);
286 if (err == 0)
287 tfilter_notify(skb, n, tp, fh, RTM_DELTFILTER);
288 goto errout;
289 case RTM_GETTFILTER:
290 err = tfilter_notify(skb, n, tp, fh, RTM_NEWTFILTER);
291 goto errout;
292 default:
293 err = -EINVAL;
294 goto errout;
295 }
296 }
297
298 err = tp->ops->change(tp, cl, t->tcm_handle, tca, &fh);
299 if (err == 0)
300 tfilter_notify(skb, n, tp, fh, RTM_NEWTFILTER);
301
302errout:
303 if (cl)
304 cops->put(q, cl);
305 if (err == -EAGAIN)
306 /* Replay the request. */
307 goto replay;
308 return err;
309}
310
311static int
312tcf_fill_node(struct sk_buff *skb, struct tcf_proto *tp, unsigned long fh,
Jamal Hadi Salime431b8c2005-06-18 22:55:31 -0700313 u32 pid, u32 seq, u16 flags, int event)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700314{
315 struct tcmsg *tcm;
316 struct nlmsghdr *nlh;
Arnaldo Carvalho de Melo27a884d2007-04-19 20:29:13 -0700317 unsigned char *b = skb_tail_pointer(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700318
Jamal Hadi Salime431b8c2005-06-18 22:55:31 -0700319 nlh = NLMSG_NEW(skb, pid, seq, event, sizeof(*tcm), flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700320 tcm = NLMSG_DATA(nlh);
321 tcm->tcm_family = AF_UNSPEC;
Patrick McHardy9ef1d4c2005-06-28 12:55:30 -0700322 tcm->tcm__pad1 = 0;
323 tcm->tcm__pad1 = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700324 tcm->tcm_ifindex = tp->q->dev->ifindex;
325 tcm->tcm_parent = tp->classid;
326 tcm->tcm_info = TC_H_MAKE(tp->prio, tp->protocol);
327 RTA_PUT(skb, TCA_KIND, IFNAMSIZ, tp->ops->kind);
328 tcm->tcm_handle = fh;
329 if (RTM_DELTFILTER != event) {
330 tcm->tcm_handle = 0;
331 if (tp->ops->dump && tp->ops->dump(tp, fh, skb, tcm) < 0)
332 goto rtattr_failure;
333 }
Arnaldo Carvalho de Melo27a884d2007-04-19 20:29:13 -0700334 nlh->nlmsg_len = skb_tail_pointer(skb) - b;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700335 return skb->len;
336
337nlmsg_failure:
338rtattr_failure:
Arnaldo Carvalho de Melodc5fc572007-03-25 23:06:12 -0700339 nlmsg_trim(skb, b);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700340 return -1;
341}
342
343static int tfilter_notify(struct sk_buff *oskb, struct nlmsghdr *n,
344 struct tcf_proto *tp, unsigned long fh, int event)
345{
346 struct sk_buff *skb;
347 u32 pid = oskb ? NETLINK_CB(oskb).pid : 0;
348
349 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
350 if (!skb)
351 return -ENOBUFS;
352
353 if (tcf_fill_node(skb, tp, fh, pid, n->nlmsg_seq, 0, event) <= 0) {
354 kfree_skb(skb);
355 return -EINVAL;
356 }
357
Patrick McHardyac6d4392005-08-14 19:29:52 -0700358 return rtnetlink_send(skb, pid, RTNLGRP_TC, n->nlmsg_flags&NLM_F_ECHO);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700359}
360
361struct tcf_dump_args
362{
363 struct tcf_walker w;
364 struct sk_buff *skb;
365 struct netlink_callback *cb;
366};
367
368static int tcf_node_dump(struct tcf_proto *tp, unsigned long n, struct tcf_walker *arg)
369{
370 struct tcf_dump_args *a = (void*)arg;
371
372 return tcf_fill_node(a->skb, tp, n, NETLINK_CB(a->cb->skb).pid,
373 a->cb->nlh->nlmsg_seq, NLM_F_MULTI, RTM_NEWTFILTER);
374}
375
376static int tc_dump_tfilter(struct sk_buff *skb, struct netlink_callback *cb)
377{
378 int t;
379 int s_t;
380 struct net_device *dev;
381 struct Qdisc *q;
382 struct tcf_proto *tp, **chain;
383 struct tcmsg *tcm = (struct tcmsg*)NLMSG_DATA(cb->nlh);
384 unsigned long cl = 0;
385 struct Qdisc_class_ops *cops;
386 struct tcf_dump_args arg;
387
388 if (cb->nlh->nlmsg_len < NLMSG_LENGTH(sizeof(*tcm)))
389 return skb->len;
Eric W. Biederman881d9662007-09-17 11:56:21 -0700390 if ((dev = dev_get_by_index(&init_net, tcm->tcm_ifindex)) == NULL)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700391 return skb->len;
392
Linus Torvalds1da177e2005-04-16 15:20:36 -0700393 if (!tcm->tcm_parent)
394 q = dev->qdisc_sleeping;
395 else
396 q = qdisc_lookup(dev, TC_H_MAJ(tcm->tcm_parent));
397 if (!q)
398 goto out;
399 if ((cops = q->ops->cl_ops) == NULL)
400 goto errout;
401 if (TC_H_MIN(tcm->tcm_parent)) {
402 cl = cops->get(q, tcm->tcm_parent);
403 if (cl == 0)
404 goto errout;
405 }
406 chain = cops->tcf_chain(q, cl);
407 if (chain == NULL)
408 goto errout;
409
410 s_t = cb->args[0];
411
412 for (tp=*chain, t=0; tp; tp = tp->next, t++) {
413 if (t < s_t) continue;
414 if (TC_H_MAJ(tcm->tcm_info) &&
415 TC_H_MAJ(tcm->tcm_info) != tp->prio)
416 continue;
417 if (TC_H_MIN(tcm->tcm_info) &&
418 TC_H_MIN(tcm->tcm_info) != tp->protocol)
419 continue;
420 if (t > s_t)
421 memset(&cb->args[1], 0, sizeof(cb->args)-sizeof(cb->args[0]));
422 if (cb->args[1] == 0) {
423 if (tcf_fill_node(skb, tp, 0, NETLINK_CB(cb->skb).pid,
424 cb->nlh->nlmsg_seq, NLM_F_MULTI, RTM_NEWTFILTER) <= 0) {
425 break;
426 }
427 cb->args[1] = 1;
428 }
429 if (tp->ops->walk == NULL)
430 continue;
431 arg.w.fn = tcf_node_dump;
432 arg.skb = skb;
433 arg.cb = cb;
434 arg.w.stop = 0;
435 arg.w.skip = cb->args[1]-1;
436 arg.w.count = 0;
437 tp->ops->walk(tp, &arg.w);
438 cb->args[1] = arg.w.count+1;
439 if (arg.w.stop)
440 break;
441 }
442
443 cb->args[0] = t;
444
445errout:
446 if (cl)
447 cops->put(q, cl);
448out:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700449 dev_put(dev);
450 return skb->len;
451}
452
453void
454tcf_exts_destroy(struct tcf_proto *tp, struct tcf_exts *exts)
455{
456#ifdef CONFIG_NET_CLS_ACT
457 if (exts->action) {
458 tcf_action_destroy(exts->action, TCA_ACT_UNBIND);
459 exts->action = NULL;
460 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700461#endif
462}
463
464
465int
466tcf_exts_validate(struct tcf_proto *tp, struct rtattr **tb,
YOSHIFUJI Hideaki10297b92007-02-09 23:25:16 +0900467 struct rtattr *rate_tlv, struct tcf_exts *exts,
468 struct tcf_ext_map *map)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700469{
470 memset(exts, 0, sizeof(*exts));
YOSHIFUJI Hideaki10297b92007-02-09 23:25:16 +0900471
Linus Torvalds1da177e2005-04-16 15:20:36 -0700472#ifdef CONFIG_NET_CLS_ACT
473 {
474 int err;
475 struct tc_action *act;
476
477 if (map->police && tb[map->police-1]) {
478 act = tcf_action_init_1(tb[map->police-1], rate_tlv, "police",
479 TCA_ACT_NOREPLACE, TCA_ACT_BIND, &err);
480 if (act == NULL)
481 return err;
482
483 act->type = TCA_OLD_COMPAT;
484 exts->action = act;
485 } else if (map->action && tb[map->action-1]) {
486 act = tcf_action_init(tb[map->action-1], rate_tlv, NULL,
487 TCA_ACT_NOREPLACE, TCA_ACT_BIND, &err);
488 if (act == NULL)
489 return err;
490
491 exts->action = act;
492 }
493 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700494#else
495 if ((map->action && tb[map->action-1]) ||
496 (map->police && tb[map->police-1]))
497 return -EOPNOTSUPP;
498#endif
499
500 return 0;
501}
502
503void
504tcf_exts_change(struct tcf_proto *tp, struct tcf_exts *dst,
YOSHIFUJI Hideaki10297b92007-02-09 23:25:16 +0900505 struct tcf_exts *src)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700506{
507#ifdef CONFIG_NET_CLS_ACT
508 if (src->action) {
509 struct tc_action *act;
510 tcf_tree_lock(tp);
511 act = xchg(&dst->action, src->action);
512 tcf_tree_unlock(tp);
513 if (act)
514 tcf_action_destroy(act, TCA_ACT_UNBIND);
515 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700516#endif
517}
518
519int
520tcf_exts_dump(struct sk_buff *skb, struct tcf_exts *exts,
521 struct tcf_ext_map *map)
522{
523#ifdef CONFIG_NET_CLS_ACT
524 if (map->action && exts->action) {
525 /*
526 * again for backward compatible mode - we want
527 * to work with both old and new modes of entering
528 * tc data even if iproute2 was newer - jhs
529 */
Arnaldo Carvalho de Melo27a884d2007-04-19 20:29:13 -0700530 struct rtattr *p_rta = (struct rtattr *)skb_tail_pointer(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700531
532 if (exts->action->type != TCA_OLD_COMPAT) {
533 RTA_PUT(skb, map->action, 0, NULL);
534 if (tcf_action_dump(skb, exts->action, 0, 0) < 0)
535 goto rtattr_failure;
Arnaldo Carvalho de Melo27a884d2007-04-19 20:29:13 -0700536 p_rta->rta_len = skb_tail_pointer(skb) - (u8 *)p_rta;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700537 } else if (map->police) {
538 RTA_PUT(skb, map->police, 0, NULL);
539 if (tcf_action_dump_old(skb, exts->action, 0, 0) < 0)
540 goto rtattr_failure;
Arnaldo Carvalho de Melo27a884d2007-04-19 20:29:13 -0700541 p_rta->rta_len = skb_tail_pointer(skb) - (u8 *)p_rta;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700542 }
543 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700544#endif
545 return 0;
546rtattr_failure: __attribute__ ((unused))
547 return -1;
548}
549
550int
551tcf_exts_dump_stats(struct sk_buff *skb, struct tcf_exts *exts,
YOSHIFUJI Hideaki10297b92007-02-09 23:25:16 +0900552 struct tcf_ext_map *map)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700553{
554#ifdef CONFIG_NET_CLS_ACT
555 if (exts->action)
556 if (tcf_action_copy_stats(skb, exts->action, 1) < 0)
557 goto rtattr_failure;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700558#endif
559 return 0;
560rtattr_failure: __attribute__ ((unused))
561 return -1;
562}
563
564static int __init tc_filter_init(void)
565{
Thomas Graf82623c02007-03-22 11:56:22 -0700566 rtnl_register(PF_UNSPEC, RTM_NEWTFILTER, tc_ctl_tfilter, NULL);
567 rtnl_register(PF_UNSPEC, RTM_DELTFILTER, tc_ctl_tfilter, NULL);
568 rtnl_register(PF_UNSPEC, RTM_GETTFILTER, tc_ctl_tfilter,
569 tc_dump_tfilter);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700570
Linus Torvalds1da177e2005-04-16 15:20:36 -0700571 return 0;
572}
573
574subsys_initcall(tc_filter_init);
575
576EXPORT_SYMBOL(register_tcf_proto_ops);
577EXPORT_SYMBOL(unregister_tcf_proto_ops);
578EXPORT_SYMBOL(tcf_exts_validate);
579EXPORT_SYMBOL(tcf_exts_destroy);
580EXPORT_SYMBOL(tcf_exts_change);
581EXPORT_SYMBOL(tcf_exts_dump);
582EXPORT_SYMBOL(tcf_exts_dump_stats);