1 /*
2 * net/sched/act_api.c Packet action API.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License
6 * as published by the Free Software Foundation; either version
7 * 2 of the License, or (at your option) any later version.
8 *
9 * Author: Jamal Hadi Salim
10 *
11 *
12 */
13
14 #include <linux/types.h>
15 #include <linux/kernel.h>
16 #include <linux/string.h>
17 #include <linux/errno.h>
18 #include <linux/slab.h>
19 #include <linux/skbuff.h>
20 #include <linux/init.h>
21 #include <linux/kmod.h>
22 #include <linux/err.h>
23 #include <linux/module.h>
24 #include <net/net_namespace.h>
25 #include <net/sock.h>
26 #include <net/sch_generic.h>
27 #include <net/act_api.h>
28 #include <net/netlink.h>
29
tcf_hash_destroy(struct tc_action * a)30 void tcf_hash_destroy(struct tc_action *a)
31 {
32 struct tcf_common *p = a->priv;
33 struct tcf_hashinfo *hinfo = a->ops->hinfo;
34
35 spin_lock_bh(&hinfo->lock);
36 hlist_del(&p->tcfc_head);
37 spin_unlock_bh(&hinfo->lock);
38 gen_kill_estimator(&p->tcfc_bstats,
39 &p->tcfc_rate_est);
40 /*
41 * gen_estimator est_timer() might access p->tcfc_lock
42 * or bstats, wait a RCU grace period before freeing p
43 */
44 kfree_rcu(p, tcfc_rcu);
45 }
46 EXPORT_SYMBOL(tcf_hash_destroy);
47
tcf_hash_release(struct tc_action * a,int bind)48 int tcf_hash_release(struct tc_action *a, int bind)
49 {
50 struct tcf_common *p = a->priv;
51 int ret = 0;
52
53 if (p) {
54 if (bind)
55 p->tcfc_bindcnt--;
56 else if (p->tcfc_bindcnt > 0)
57 return -EPERM;
58
59 p->tcfc_refcnt--;
60 if (p->tcfc_bindcnt <= 0 && p->tcfc_refcnt <= 0) {
61 if (a->ops->cleanup)
62 a->ops->cleanup(a, bind);
63 tcf_hash_destroy(a);
64 ret = 1;
65 }
66 }
67 return ret;
68 }
69 EXPORT_SYMBOL(tcf_hash_release);
70
tcf_dump_walker(struct sk_buff * skb,struct netlink_callback * cb,struct tc_action * a)71 static int tcf_dump_walker(struct sk_buff *skb, struct netlink_callback *cb,
72 struct tc_action *a)
73 {
74 struct tcf_hashinfo *hinfo = a->ops->hinfo;
75 struct hlist_head *head;
76 struct tcf_common *p;
77 int err = 0, index = -1, i = 0, s_i = 0, n_i = 0;
78 struct nlattr *nest;
79
80 spin_lock_bh(&hinfo->lock);
81
82 s_i = cb->args[0];
83
84 for (i = 0; i < (hinfo->hmask + 1); i++) {
85 head = &hinfo->htab[tcf_hash(i, hinfo->hmask)];
86
87 hlist_for_each_entry_rcu(p, head, tcfc_head) {
88 index++;
89 if (index < s_i)
90 continue;
91 a->priv = p;
92 a->order = n_i;
93
94 nest = nla_nest_start(skb, a->order);
95 if (nest == NULL)
96 goto nla_put_failure;
97 err = tcf_action_dump_1(skb, a, 0, 0);
98 if (err < 0) {
99 index--;
100 nlmsg_trim(skb, nest);
101 goto done;
102 }
103 nla_nest_end(skb, nest);
104 n_i++;
105 if (n_i >= TCA_ACT_MAX_PRIO)
106 goto done;
107 }
108 }
109 done:
110 spin_unlock_bh(&hinfo->lock);
111 if (n_i)
112 cb->args[0] += n_i;
113 return n_i;
114
115 nla_put_failure:
116 nla_nest_cancel(skb, nest);
117 goto done;
118 }
119
tcf_del_walker(struct sk_buff * skb,struct tc_action * a)120 static int tcf_del_walker(struct sk_buff *skb, struct tc_action *a)
121 {
122 struct tcf_hashinfo *hinfo = a->ops->hinfo;
123 struct hlist_head *head;
124 struct hlist_node *n;
125 struct tcf_common *p;
126 struct nlattr *nest;
127 int i = 0, n_i = 0;
128 int ret = -EINVAL;
129
130 nest = nla_nest_start(skb, a->order);
131 if (nest == NULL)
132 goto nla_put_failure;
133 if (nla_put_string(skb, TCA_KIND, a->ops->kind))
134 goto nla_put_failure;
135 for (i = 0; i < (hinfo->hmask + 1); i++) {
136 head = &hinfo->htab[tcf_hash(i, hinfo->hmask)];
137 hlist_for_each_entry_safe(p, n, head, tcfc_head) {
138 a->priv = p;
139 ret = tcf_hash_release(a, 0);
140 if (ret == ACT_P_DELETED) {
141 module_put(a->ops->owner);
142 n_i++;
143 } else if (ret < 0)
144 goto nla_put_failure;
145 }
146 }
147 if (nla_put_u32(skb, TCA_FCNT, n_i))
148 goto nla_put_failure;
149 nla_nest_end(skb, nest);
150
151 return n_i;
152 nla_put_failure:
153 nla_nest_cancel(skb, nest);
154 return ret;
155 }
156
tcf_generic_walker(struct sk_buff * skb,struct netlink_callback * cb,int type,struct tc_action * a)157 static int tcf_generic_walker(struct sk_buff *skb, struct netlink_callback *cb,
158 int type, struct tc_action *a)
159 {
160 if (type == RTM_DELACTION) {
161 return tcf_del_walker(skb, a);
162 } else if (type == RTM_GETACTION) {
163 return tcf_dump_walker(skb, cb, a);
164 } else {
165 WARN(1, "tcf_generic_walker: unknown action %d\n", type);
166 return -EINVAL;
167 }
168 }
169
tcf_hash_lookup(u32 index,struct tcf_hashinfo * hinfo)170 static struct tcf_common *tcf_hash_lookup(u32 index, struct tcf_hashinfo *hinfo)
171 {
172 struct tcf_common *p = NULL;
173 struct hlist_head *head;
174
175 spin_lock_bh(&hinfo->lock);
176 head = &hinfo->htab[tcf_hash(index, hinfo->hmask)];
177 hlist_for_each_entry_rcu(p, head, tcfc_head)
178 if (p->tcfc_index == index)
179 break;
180 spin_unlock_bh(&hinfo->lock);
181
182 return p;
183 }
184
tcf_hash_new_index(struct tcf_hashinfo * hinfo)185 u32 tcf_hash_new_index(struct tcf_hashinfo *hinfo)
186 {
187 u32 val = hinfo->index;
188
189 do {
190 if (++val == 0)
191 val = 1;
192 } while (tcf_hash_lookup(val, hinfo));
193
194 hinfo->index = val;
195 return val;
196 }
197 EXPORT_SYMBOL(tcf_hash_new_index);
198
tcf_hash_search(struct tc_action * a,u32 index)199 int tcf_hash_search(struct tc_action *a, u32 index)
200 {
201 struct tcf_hashinfo *hinfo = a->ops->hinfo;
202 struct tcf_common *p = tcf_hash_lookup(index, hinfo);
203
204 if (p) {
205 a->priv = p;
206 return 1;
207 }
208 return 0;
209 }
210 EXPORT_SYMBOL(tcf_hash_search);
211
tcf_hash_check(u32 index,struct tc_action * a,int bind)212 int tcf_hash_check(u32 index, struct tc_action *a, int bind)
213 {
214 struct tcf_hashinfo *hinfo = a->ops->hinfo;
215 struct tcf_common *p = NULL;
216 if (index && (p = tcf_hash_lookup(index, hinfo)) != NULL) {
217 if (bind)
218 p->tcfc_bindcnt++;
219 p->tcfc_refcnt++;
220 a->priv = p;
221 return 1;
222 }
223 return 0;
224 }
225 EXPORT_SYMBOL(tcf_hash_check);
226
tcf_hash_cleanup(struct tc_action * a,struct nlattr * est)227 void tcf_hash_cleanup(struct tc_action *a, struct nlattr *est)
228 {
229 struct tcf_common *pc = a->priv;
230 if (est)
231 gen_kill_estimator(&pc->tcfc_bstats,
232 &pc->tcfc_rate_est);
233 kfree_rcu(pc, tcfc_rcu);
234 }
235 EXPORT_SYMBOL(tcf_hash_cleanup);
236
tcf_hash_create(u32 index,struct nlattr * est,struct tc_action * a,int size,int bind)237 int tcf_hash_create(u32 index, struct nlattr *est, struct tc_action *a,
238 int size, int bind)
239 {
240 struct tcf_hashinfo *hinfo = a->ops->hinfo;
241 struct tcf_common *p = kzalloc(size, GFP_KERNEL);
242
243 if (unlikely(!p))
244 return -ENOMEM;
245 p->tcfc_refcnt = 1;
246 if (bind)
247 p->tcfc_bindcnt = 1;
248
249 spin_lock_init(&p->tcfc_lock);
250 INIT_HLIST_NODE(&p->tcfc_head);
251 p->tcfc_index = index ? index : tcf_hash_new_index(hinfo);
252 p->tcfc_tm.install = jiffies;
253 p->tcfc_tm.lastuse = jiffies;
254 if (est) {
255 int err = gen_new_estimator(&p->tcfc_bstats, NULL,
256 &p->tcfc_rate_est,
257 &p->tcfc_lock, est);
258 if (err) {
259 kfree(p);
260 return err;
261 }
262 }
263
264 a->priv = (void *) p;
265 return 0;
266 }
267 EXPORT_SYMBOL(tcf_hash_create);
268
tcf_hash_insert(struct tc_action * a)269 void tcf_hash_insert(struct tc_action *a)
270 {
271 struct tcf_common *p = a->priv;
272 struct tcf_hashinfo *hinfo = a->ops->hinfo;
273 unsigned int h = tcf_hash(p->tcfc_index, hinfo->hmask);
274
275 spin_lock_bh(&hinfo->lock);
276 hlist_add_head(&p->tcfc_head, &hinfo->htab[h]);
277 spin_unlock_bh(&hinfo->lock);
278 }
279 EXPORT_SYMBOL(tcf_hash_insert);
280
281 static LIST_HEAD(act_base);
282 static DEFINE_RWLOCK(act_mod_lock);
283
tcf_register_action(struct tc_action_ops * act,unsigned int mask)284 int tcf_register_action(struct tc_action_ops *act, unsigned int mask)
285 {
286 struct tc_action_ops *a;
287 int err;
288
289 /* Must supply act, dump and init */
290 if (!act->act || !act->dump || !act->init)
291 return -EINVAL;
292
293 /* Supply defaults */
294 if (!act->lookup)
295 act->lookup = tcf_hash_search;
296 if (!act->walk)
297 act->walk = tcf_generic_walker;
298
299 act->hinfo = kmalloc(sizeof(struct tcf_hashinfo), GFP_KERNEL);
300 if (!act->hinfo)
301 return -ENOMEM;
302 err = tcf_hashinfo_init(act->hinfo, mask);
303 if (err) {
304 kfree(act->hinfo);
305 return err;
306 }
307
308 write_lock(&act_mod_lock);
309 list_for_each_entry(a, &act_base, head) {
310 if (act->type == a->type || (strcmp(act->kind, a->kind) == 0)) {
311 write_unlock(&act_mod_lock);
312 tcf_hashinfo_destroy(act->hinfo);
313 kfree(act->hinfo);
314 return -EEXIST;
315 }
316 }
317 list_add_tail(&act->head, &act_base);
318 write_unlock(&act_mod_lock);
319 return 0;
320 }
321 EXPORT_SYMBOL(tcf_register_action);
322
tcf_unregister_action(struct tc_action_ops * act)323 int tcf_unregister_action(struct tc_action_ops *act)
324 {
325 struct tc_action_ops *a;
326 int err = -ENOENT;
327
328 write_lock(&act_mod_lock);
329 list_for_each_entry(a, &act_base, head) {
330 if (a == act) {
331 list_del(&act->head);
332 tcf_hashinfo_destroy(act->hinfo);
333 kfree(act->hinfo);
334 err = 0;
335 break;
336 }
337 }
338 write_unlock(&act_mod_lock);
339 return err;
340 }
341 EXPORT_SYMBOL(tcf_unregister_action);
342
343 /* lookup by name */
tc_lookup_action_n(char * kind)344 static struct tc_action_ops *tc_lookup_action_n(char *kind)
345 {
346 struct tc_action_ops *a, *res = NULL;
347
348 if (kind) {
349 read_lock(&act_mod_lock);
350 list_for_each_entry(a, &act_base, head) {
351 if (strcmp(kind, a->kind) == 0) {
352 if (try_module_get(a->owner))
353 res = a;
354 break;
355 }
356 }
357 read_unlock(&act_mod_lock);
358 }
359 return res;
360 }
361
362 /* lookup by nlattr */
tc_lookup_action(struct nlattr * kind)363 static struct tc_action_ops *tc_lookup_action(struct nlattr *kind)
364 {
365 struct tc_action_ops *a, *res = NULL;
366
367 if (kind) {
368 read_lock(&act_mod_lock);
369 list_for_each_entry(a, &act_base, head) {
370 if (nla_strcmp(kind, a->kind) == 0) {
371 if (try_module_get(a->owner))
372 res = a;
373 break;
374 }
375 }
376 read_unlock(&act_mod_lock);
377 }
378 return res;
379 }
380
tcf_action_exec(struct sk_buff * skb,const struct list_head * actions,struct tcf_result * res)381 int tcf_action_exec(struct sk_buff *skb, const struct list_head *actions,
382 struct tcf_result *res)
383 {
384 const struct tc_action *a;
385 int ret = -1;
386
387 if (skb->tc_verd & TC_NCLS) {
388 skb->tc_verd = CLR_TC_NCLS(skb->tc_verd);
389 ret = TC_ACT_OK;
390 goto exec_done;
391 }
392 list_for_each_entry(a, actions, list) {
393 repeat:
394 ret = a->ops->act(skb, a, res);
395 if (TC_MUNGED & skb->tc_verd) {
396 /* copied already, allow trampling */
397 skb->tc_verd = SET_TC_OK2MUNGE(skb->tc_verd);
398 skb->tc_verd = CLR_TC_MUNGED(skb->tc_verd);
399 }
400 if (ret == TC_ACT_REPEAT)
401 goto repeat; /* we need a ttl - JHS */
402 if (ret != TC_ACT_PIPE)
403 goto exec_done;
404 }
405 exec_done:
406 return ret;
407 }
408 EXPORT_SYMBOL(tcf_action_exec);
409
tcf_action_destroy(struct list_head * actions,int bind)410 int tcf_action_destroy(struct list_head *actions, int bind)
411 {
412 struct tc_action *a, *tmp;
413 int ret = 0;
414
415 list_for_each_entry_safe(a, tmp, actions, list) {
416 ret = tcf_hash_release(a, bind);
417 if (ret == ACT_P_DELETED)
418 module_put(a->ops->owner);
419 else if (ret < 0)
420 return ret;
421 list_del(&a->list);
422 kfree(a);
423 }
424 return ret;
425 }
426
427 int
tcf_action_dump_old(struct sk_buff * skb,struct tc_action * a,int bind,int ref)428 tcf_action_dump_old(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
429 {
430 return a->ops->dump(skb, a, bind, ref);
431 }
432
433 int
tcf_action_dump_1(struct sk_buff * skb,struct tc_action * a,int bind,int ref)434 tcf_action_dump_1(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
435 {
436 int err = -EINVAL;
437 unsigned char *b = skb_tail_pointer(skb);
438 struct nlattr *nest;
439
440 if (nla_put_string(skb, TCA_KIND, a->ops->kind))
441 goto nla_put_failure;
442 if (tcf_action_copy_stats(skb, a, 0))
443 goto nla_put_failure;
444 nest = nla_nest_start(skb, TCA_OPTIONS);
445 if (nest == NULL)
446 goto nla_put_failure;
447 err = tcf_action_dump_old(skb, a, bind, ref);
448 if (err > 0) {
449 nla_nest_end(skb, nest);
450 return err;
451 }
452
453 nla_put_failure:
454 nlmsg_trim(skb, b);
455 return -1;
456 }
457 EXPORT_SYMBOL(tcf_action_dump_1);
458
459 int
tcf_action_dump(struct sk_buff * skb,struct list_head * actions,int bind,int ref)460 tcf_action_dump(struct sk_buff *skb, struct list_head *actions, int bind, int ref)
461 {
462 struct tc_action *a;
463 int err = -EINVAL;
464 struct nlattr *nest;
465
466 list_for_each_entry(a, actions, list) {
467 nest = nla_nest_start(skb, a->order);
468 if (nest == NULL)
469 goto nla_put_failure;
470 err = tcf_action_dump_1(skb, a, bind, ref);
471 if (err < 0)
472 goto errout;
473 nla_nest_end(skb, nest);
474 }
475
476 return 0;
477
478 nla_put_failure:
479 err = -EINVAL;
480 errout:
481 nla_nest_cancel(skb, nest);
482 return err;
483 }
484
tcf_action_init_1(struct net * net,struct nlattr * nla,struct nlattr * est,char * name,int ovr,int bind)485 struct tc_action *tcf_action_init_1(struct net *net, struct nlattr *nla,
486 struct nlattr *est, char *name, int ovr,
487 int bind)
488 {
489 struct tc_action *a;
490 struct tc_action_ops *a_o;
491 char act_name[IFNAMSIZ];
492 struct nlattr *tb[TCA_ACT_MAX + 1];
493 struct nlattr *kind;
494 int err;
495
496 if (name == NULL) {
497 err = nla_parse_nested(tb, TCA_ACT_MAX, nla, NULL);
498 if (err < 0)
499 goto err_out;
500 err = -EINVAL;
501 kind = tb[TCA_ACT_KIND];
502 if (kind == NULL)
503 goto err_out;
504 if (nla_strlcpy(act_name, kind, IFNAMSIZ) >= IFNAMSIZ)
505 goto err_out;
506 } else {
507 err = -EINVAL;
508 if (strlcpy(act_name, name, IFNAMSIZ) >= IFNAMSIZ)
509 goto err_out;
510 }
511
512 a_o = tc_lookup_action_n(act_name);
513 if (a_o == NULL) {
514 #ifdef CONFIG_MODULES
515 rtnl_unlock();
516 request_module("act_%s", act_name);
517 rtnl_lock();
518
519 a_o = tc_lookup_action_n(act_name);
520
521 /* We dropped the RTNL semaphore in order to
522 * perform the module load. So, even if we
523 * succeeded in loading the module we have to
524 * tell the caller to replay the request. We
525 * indicate this using -EAGAIN.
526 */
527 if (a_o != NULL) {
528 err = -EAGAIN;
529 goto err_mod;
530 }
531 #endif
532 err = -ENOENT;
533 goto err_out;
534 }
535
536 err = -ENOMEM;
537 a = kzalloc(sizeof(*a), GFP_KERNEL);
538 if (a == NULL)
539 goto err_mod;
540
541 a->ops = a_o;
542 INIT_LIST_HEAD(&a->list);
543 /* backward compatibility for policer */
544 if (name == NULL)
545 err = a_o->init(net, tb[TCA_ACT_OPTIONS], est, a, ovr, bind);
546 else
547 err = a_o->init(net, nla, est, a, ovr, bind);
548 if (err < 0)
549 goto err_free;
550
551 /* module count goes up only when brand new policy is created
552 * if it exists and is only bound to in a_o->init() then
553 * ACT_P_CREATED is not returned (a zero is).
554 */
555 if (err != ACT_P_CREATED)
556 module_put(a_o->owner);
557
558 return a;
559
560 err_free:
561 kfree(a);
562 err_mod:
563 module_put(a_o->owner);
564 err_out:
565 return ERR_PTR(err);
566 }
567
tcf_action_init(struct net * net,struct nlattr * nla,struct nlattr * est,char * name,int ovr,int bind,struct list_head * actions)568 int tcf_action_init(struct net *net, struct nlattr *nla,
569 struct nlattr *est, char *name, int ovr,
570 int bind, struct list_head *actions)
571 {
572 struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
573 struct tc_action *act;
574 int err;
575 int i;
576
577 err = nla_parse_nested(tb, TCA_ACT_MAX_PRIO, nla, NULL);
578 if (err < 0)
579 return err;
580
581 for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
582 act = tcf_action_init_1(net, tb[i], est, name, ovr, bind);
583 if (IS_ERR(act)) {
584 err = PTR_ERR(act);
585 goto err;
586 }
587 act->order = i;
588 list_add_tail(&act->list, actions);
589 }
590 return 0;
591
592 err:
593 tcf_action_destroy(actions, bind);
594 return err;
595 }
596
tcf_action_copy_stats(struct sk_buff * skb,struct tc_action * a,int compat_mode)597 int tcf_action_copy_stats(struct sk_buff *skb, struct tc_action *a,
598 int compat_mode)
599 {
600 int err = 0;
601 struct gnet_dump d;
602 struct tcf_common *p = a->priv;
603
604 if (p == NULL)
605 goto errout;
606
607 /* compat_mode being true specifies a call that is supposed
608 * to add additional backward compatibility statistic TLVs.
609 */
610 if (compat_mode) {
611 if (a->type == TCA_OLD_COMPAT)
612 err = gnet_stats_start_copy_compat(skb, 0,
613 TCA_STATS, TCA_XSTATS, &p->tcfc_lock, &d);
614 else
615 return 0;
616 } else
617 err = gnet_stats_start_copy(skb, TCA_ACT_STATS,
618 &p->tcfc_lock, &d);
619
620 if (err < 0)
621 goto errout;
622
623 if (gnet_stats_copy_basic(&d, NULL, &p->tcfc_bstats) < 0 ||
624 gnet_stats_copy_rate_est(&d, &p->tcfc_bstats,
625 &p->tcfc_rate_est) < 0 ||
626 gnet_stats_copy_queue(&d, NULL,
627 &p->tcfc_qstats,
628 p->tcfc_qstats.qlen) < 0)
629 goto errout;
630
631 if (gnet_stats_finish_copy(&d) < 0)
632 goto errout;
633
634 return 0;
635
636 errout:
637 return -1;
638 }
639
640 static int
tca_get_fill(struct sk_buff * skb,struct list_head * actions,u32 portid,u32 seq,u16 flags,int event,int bind,int ref)641 tca_get_fill(struct sk_buff *skb, struct list_head *actions, u32 portid, u32 seq,
642 u16 flags, int event, int bind, int ref)
643 {
644 struct tcamsg *t;
645 struct nlmsghdr *nlh;
646 unsigned char *b = skb_tail_pointer(skb);
647 struct nlattr *nest;
648
649 nlh = nlmsg_put(skb, portid, seq, event, sizeof(*t), flags);
650 if (!nlh)
651 goto out_nlmsg_trim;
652 t = nlmsg_data(nlh);
653 t->tca_family = AF_UNSPEC;
654 t->tca__pad1 = 0;
655 t->tca__pad2 = 0;
656
657 nest = nla_nest_start(skb, TCA_ACT_TAB);
658 if (nest == NULL)
659 goto out_nlmsg_trim;
660
661 if (tcf_action_dump(skb, actions, bind, ref) < 0)
662 goto out_nlmsg_trim;
663
664 nla_nest_end(skb, nest);
665
666 nlh->nlmsg_len = skb_tail_pointer(skb) - b;
667 return skb->len;
668
669 out_nlmsg_trim:
670 nlmsg_trim(skb, b);
671 return -1;
672 }
673
674 static int
act_get_notify(struct net * net,u32 portid,struct nlmsghdr * n,struct list_head * actions,int event)675 act_get_notify(struct net *net, u32 portid, struct nlmsghdr *n,
676 struct list_head *actions, int event)
677 {
678 struct sk_buff *skb;
679
680 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
681 if (!skb)
682 return -ENOBUFS;
683 if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, 0, event, 0, 0) <= 0) {
684 kfree_skb(skb);
685 return -EINVAL;
686 }
687
688 return rtnl_unicast(skb, net, portid);
689 }
690
create_a(int i)691 static struct tc_action *create_a(int i)
692 {
693 struct tc_action *act;
694
695 act = kzalloc(sizeof(*act), GFP_KERNEL);
696 if (act == NULL) {
697 pr_debug("create_a: failed to alloc!\n");
698 return NULL;
699 }
700 act->order = i;
701 INIT_LIST_HEAD(&act->list);
702 return act;
703 }
704
705 static struct tc_action *
tcf_action_get_1(struct nlattr * nla,struct nlmsghdr * n,u32 portid)706 tcf_action_get_1(struct nlattr *nla, struct nlmsghdr *n, u32 portid)
707 {
708 struct nlattr *tb[TCA_ACT_MAX + 1];
709 struct tc_action *a;
710 int index;
711 int err;
712
713 err = nla_parse_nested(tb, TCA_ACT_MAX, nla, NULL);
714 if (err < 0)
715 goto err_out;
716
717 err = -EINVAL;
718 if (tb[TCA_ACT_INDEX] == NULL ||
719 nla_len(tb[TCA_ACT_INDEX]) < sizeof(index))
720 goto err_out;
721 index = nla_get_u32(tb[TCA_ACT_INDEX]);
722
723 err = -ENOMEM;
724 a = create_a(0);
725 if (a == NULL)
726 goto err_out;
727
728 err = -EINVAL;
729 a->ops = tc_lookup_action(tb[TCA_ACT_KIND]);
730 if (a->ops == NULL) /* could happen in batch of actions */
731 goto err_free;
732 err = -ENOENT;
733 if (a->ops->lookup(a, index) == 0)
734 goto err_mod;
735
736 module_put(a->ops->owner);
737 return a;
738
739 err_mod:
740 module_put(a->ops->owner);
741 err_free:
742 kfree(a);
743 err_out:
744 return ERR_PTR(err);
745 }
746
cleanup_a(struct list_head * actions)747 static void cleanup_a(struct list_head *actions)
748 {
749 struct tc_action *a, *tmp;
750
751 list_for_each_entry_safe(a, tmp, actions, list) {
752 list_del(&a->list);
753 kfree(a);
754 }
755 }
756
tca_action_flush(struct net * net,struct nlattr * nla,struct nlmsghdr * n,u32 portid)757 static int tca_action_flush(struct net *net, struct nlattr *nla,
758 struct nlmsghdr *n, u32 portid)
759 {
760 struct sk_buff *skb;
761 unsigned char *b;
762 struct nlmsghdr *nlh;
763 struct tcamsg *t;
764 struct netlink_callback dcb;
765 struct nlattr *nest;
766 struct nlattr *tb[TCA_ACT_MAX + 1];
767 struct nlattr *kind;
768 struct tc_action a;
769 int err = -ENOMEM;
770
771 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
772 if (!skb) {
773 pr_debug("tca_action_flush: failed skb alloc\n");
774 return err;
775 }
776
777 b = skb_tail_pointer(skb);
778
779 err = nla_parse_nested(tb, TCA_ACT_MAX, nla, NULL);
780 if (err < 0)
781 goto err_out;
782
783 err = -EINVAL;
784 kind = tb[TCA_ACT_KIND];
785 memset(&a, 0, sizeof(struct tc_action));
786 INIT_LIST_HEAD(&a.list);
787 a.ops = tc_lookup_action(kind);
788 if (a.ops == NULL) /*some idjot trying to flush unknown action */
789 goto err_out;
790
791 nlh = nlmsg_put(skb, portid, n->nlmsg_seq, RTM_DELACTION, sizeof(*t), 0);
792 if (!nlh)
793 goto out_module_put;
794 t = nlmsg_data(nlh);
795 t->tca_family = AF_UNSPEC;
796 t->tca__pad1 = 0;
797 t->tca__pad2 = 0;
798
799 nest = nla_nest_start(skb, TCA_ACT_TAB);
800 if (nest == NULL)
801 goto out_module_put;
802
803 err = a.ops->walk(skb, &dcb, RTM_DELACTION, &a);
804 if (err <= 0)
805 goto out_module_put;
806
807 nla_nest_end(skb, nest);
808
809 nlh->nlmsg_len = skb_tail_pointer(skb) - b;
810 nlh->nlmsg_flags |= NLM_F_ROOT;
811 module_put(a.ops->owner);
812 err = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
813 n->nlmsg_flags & NLM_F_ECHO);
814 if (err > 0)
815 return 0;
816
817 return err;
818
819 out_module_put:
820 module_put(a.ops->owner);
821 err_out:
822 kfree_skb(skb);
823 return err;
824 }
825
826 static int
tcf_del_notify(struct net * net,struct nlmsghdr * n,struct list_head * actions,u32 portid)827 tcf_del_notify(struct net *net, struct nlmsghdr *n, struct list_head *actions,
828 u32 portid)
829 {
830 int ret;
831 struct sk_buff *skb;
832
833 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
834 if (!skb)
835 return -ENOBUFS;
836
837 if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, 0, RTM_DELACTION,
838 0, 1) <= 0) {
839 kfree_skb(skb);
840 return -EINVAL;
841 }
842
843 /* now do the delete */
844 ret = tcf_action_destroy(actions, 0);
845 if (ret < 0) {
846 kfree_skb(skb);
847 return ret;
848 }
849
850 ret = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
851 n->nlmsg_flags & NLM_F_ECHO);
852 if (ret > 0)
853 return 0;
854 return ret;
855 }
856
857 static int
tca_action_gd(struct net * net,struct nlattr * nla,struct nlmsghdr * n,u32 portid,int event)858 tca_action_gd(struct net *net, struct nlattr *nla, struct nlmsghdr *n,
859 u32 portid, int event)
860 {
861 int i, ret;
862 struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
863 struct tc_action *act;
864 LIST_HEAD(actions);
865
866 ret = nla_parse_nested(tb, TCA_ACT_MAX_PRIO, nla, NULL);
867 if (ret < 0)
868 return ret;
869
870 if (event == RTM_DELACTION && n->nlmsg_flags & NLM_F_ROOT) {
871 if (tb[1] != NULL)
872 return tca_action_flush(net, tb[1], n, portid);
873 else
874 return -EINVAL;
875 }
876
877 for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
878 act = tcf_action_get_1(tb[i], n, portid);
879 if (IS_ERR(act)) {
880 ret = PTR_ERR(act);
881 goto err;
882 }
883 act->order = i;
884 list_add_tail(&act->list, &actions);
885 }
886
887 if (event == RTM_GETACTION)
888 ret = act_get_notify(net, portid, n, &actions, event);
889 else { /* delete */
890 ret = tcf_del_notify(net, n, &actions, portid);
891 if (ret)
892 goto err;
893 return ret;
894 }
895 err:
896 cleanup_a(&actions);
897 return ret;
898 }
899
900 static int
tcf_add_notify(struct net * net,struct nlmsghdr * n,struct list_head * actions,u32 portid)901 tcf_add_notify(struct net *net, struct nlmsghdr *n, struct list_head *actions,
902 u32 portid)
903 {
904 struct sk_buff *skb;
905 int err = 0;
906
907 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
908 if (!skb)
909 return -ENOBUFS;
910
911 if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, n->nlmsg_flags,
912 RTM_NEWACTION, 0, 0) <= 0) {
913 kfree_skb(skb);
914 return -EINVAL;
915 }
916
917 err = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
918 n->nlmsg_flags & NLM_F_ECHO);
919 if (err > 0)
920 err = 0;
921 return err;
922 }
923
924 static int
tcf_action_add(struct net * net,struct nlattr * nla,struct nlmsghdr * n,u32 portid,int ovr)925 tcf_action_add(struct net *net, struct nlattr *nla, struct nlmsghdr *n,
926 u32 portid, int ovr)
927 {
928 int ret = 0;
929 LIST_HEAD(actions);
930
931 ret = tcf_action_init(net, nla, NULL, NULL, ovr, 0, &actions);
932 if (ret)
933 goto done;
934
935 /* dump then free all the actions after update; inserted policy
936 * stays intact
937 */
938 ret = tcf_add_notify(net, n, &actions, portid);
939 cleanup_a(&actions);
940 done:
941 return ret;
942 }
943
tc_ctl_action(struct sk_buff * skb,struct nlmsghdr * n)944 static int tc_ctl_action(struct sk_buff *skb, struct nlmsghdr *n)
945 {
946 struct net *net = sock_net(skb->sk);
947 struct nlattr *tca[TCA_ACT_MAX + 1];
948 u32 portid = skb ? NETLINK_CB(skb).portid : 0;
949 int ret = 0, ovr = 0;
950
951 if ((n->nlmsg_type != RTM_GETACTION) && !netlink_capable(skb, CAP_NET_ADMIN))
952 return -EPERM;
953
954 ret = nlmsg_parse(n, sizeof(struct tcamsg), tca, TCA_ACT_MAX, NULL);
955 if (ret < 0)
956 return ret;
957
958 if (tca[TCA_ACT_TAB] == NULL) {
959 pr_notice("tc_ctl_action: received NO action attribs\n");
960 return -EINVAL;
961 }
962
963 /* n->nlmsg_flags & NLM_F_CREATE */
964 switch (n->nlmsg_type) {
965 case RTM_NEWACTION:
966 /* we are going to assume all other flags
967 * imply create only if it doesn't exist
968 * Note that CREATE | EXCL implies that
969 * but since we want avoid ambiguity (eg when flags
970 * is zero) then just set this
971 */
972 if (n->nlmsg_flags & NLM_F_REPLACE)
973 ovr = 1;
974 replay:
975 ret = tcf_action_add(net, tca[TCA_ACT_TAB], n, portid, ovr);
976 if (ret == -EAGAIN)
977 goto replay;
978 break;
979 case RTM_DELACTION:
980 ret = tca_action_gd(net, tca[TCA_ACT_TAB], n,
981 portid, RTM_DELACTION);
982 break;
983 case RTM_GETACTION:
984 ret = tca_action_gd(net, tca[TCA_ACT_TAB], n,
985 portid, RTM_GETACTION);
986 break;
987 default:
988 BUG();
989 }
990
991 return ret;
992 }
993
994 static struct nlattr *
find_dump_kind(const struct nlmsghdr * n)995 find_dump_kind(const struct nlmsghdr *n)
996 {
997 struct nlattr *tb1, *tb2[TCA_ACT_MAX + 1];
998 struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
999 struct nlattr *nla[TCAA_MAX + 1];
1000 struct nlattr *kind;
1001
1002 if (nlmsg_parse(n, sizeof(struct tcamsg), nla, TCAA_MAX, NULL) < 0)
1003 return NULL;
1004 tb1 = nla[TCA_ACT_TAB];
1005 if (tb1 == NULL)
1006 return NULL;
1007
1008 if (nla_parse(tb, TCA_ACT_MAX_PRIO, nla_data(tb1),
1009 NLMSG_ALIGN(nla_len(tb1)), NULL) < 0)
1010 return NULL;
1011
1012 if (tb[1] == NULL)
1013 return NULL;
1014 if (nla_parse(tb2, TCA_ACT_MAX, nla_data(tb[1]),
1015 nla_len(tb[1]), NULL) < 0)
1016 return NULL;
1017 kind = tb2[TCA_ACT_KIND];
1018
1019 return kind;
1020 }
1021
1022 static int
tc_dump_action(struct sk_buff * skb,struct netlink_callback * cb)1023 tc_dump_action(struct sk_buff *skb, struct netlink_callback *cb)
1024 {
1025 struct nlmsghdr *nlh;
1026 unsigned char *b = skb_tail_pointer(skb);
1027 struct nlattr *nest;
1028 struct tc_action_ops *a_o;
1029 struct tc_action a;
1030 int ret = 0;
1031 struct tcamsg *t = (struct tcamsg *) nlmsg_data(cb->nlh);
1032 struct nlattr *kind = find_dump_kind(cb->nlh);
1033
1034 if (kind == NULL) {
1035 pr_info("tc_dump_action: action bad kind\n");
1036 return 0;
1037 }
1038
1039 a_o = tc_lookup_action(kind);
1040 if (a_o == NULL)
1041 return 0;
1042
1043 memset(&a, 0, sizeof(struct tc_action));
1044 a.ops = a_o;
1045
1046 nlh = nlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
1047 cb->nlh->nlmsg_type, sizeof(*t), 0);
1048 if (!nlh)
1049 goto out_module_put;
1050 t = nlmsg_data(nlh);
1051 t->tca_family = AF_UNSPEC;
1052 t->tca__pad1 = 0;
1053 t->tca__pad2 = 0;
1054
1055 nest = nla_nest_start(skb, TCA_ACT_TAB);
1056 if (nest == NULL)
1057 goto out_module_put;
1058
1059 ret = a_o->walk(skb, cb, RTM_GETACTION, &a);
1060 if (ret < 0)
1061 goto out_module_put;
1062
1063 if (ret > 0) {
1064 nla_nest_end(skb, nest);
1065 ret = skb->len;
1066 } else
1067 nla_nest_cancel(skb, nest);
1068
1069 nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1070 if (NETLINK_CB(cb->skb).portid && ret)
1071 nlh->nlmsg_flags |= NLM_F_MULTI;
1072 module_put(a_o->owner);
1073 return skb->len;
1074
1075 out_module_put:
1076 module_put(a_o->owner);
1077 nlmsg_trim(skb, b);
1078 return skb->len;
1079 }
1080
tc_action_init(void)1081 static int __init tc_action_init(void)
1082 {
1083 rtnl_register(PF_UNSPEC, RTM_NEWACTION, tc_ctl_action, NULL, NULL);
1084 rtnl_register(PF_UNSPEC, RTM_DELACTION, tc_ctl_action, NULL, NULL);
1085 rtnl_register(PF_UNSPEC, RTM_GETACTION, tc_ctl_action, tc_dump_action,
1086 NULL);
1087
1088 return 0;
1089 }
1090
1091 subsys_initcall(tc_action_init);
1092