0b8eb235bc136fff1eeb349f72c549a5ce4df3df
[linux-3.10.git] / net / sched / act_api.c
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/skbuff.h>
19 #include <linux/init.h>
20 #include <linux/kmod.h>
21 #include <linux/err.h>
22 #include <net/net_namespace.h>
23 #include <net/sock.h>
24 #include <net/sch_generic.h>
25 #include <net/act_api.h>
26 #include <net/netlink.h>
27
28 void tcf_hash_destroy(struct tcf_common *p, struct tcf_hashinfo *hinfo)
29 {
30         unsigned int h = tcf_hash(p->tcfc_index, hinfo->hmask);
31         struct tcf_common **p1p;
32
33         for (p1p = &hinfo->htab[h]; *p1p; p1p = &(*p1p)->tcfc_next) {
34                 if (*p1p == p) {
35                         write_lock_bh(hinfo->lock);
36                         *p1p = p->tcfc_next;
37                         write_unlock_bh(hinfo->lock);
38                         gen_kill_estimator(&p->tcfc_bstats,
39                                            &p->tcfc_rate_est);
40                         kfree(p);
41                         return;
42                 }
43         }
44         BUG_TRAP(0);
45 }
46 EXPORT_SYMBOL(tcf_hash_destroy);
47
48 int tcf_hash_release(struct tcf_common *p, int bind,
49                      struct tcf_hashinfo *hinfo)
50 {
51         int ret = 0;
52
53         if (p) {
54                 if (bind)
55                         p->tcfc_bindcnt--;
56
57                 p->tcfc_refcnt--;
58                 if (p->tcfc_bindcnt <= 0 && p->tcfc_refcnt <= 0) {
59                         tcf_hash_destroy(p, hinfo);
60                         ret = 1;
61                 }
62         }
63         return ret;
64 }
65 EXPORT_SYMBOL(tcf_hash_release);
66
67 static int tcf_dump_walker(struct sk_buff *skb, struct netlink_callback *cb,
68                            struct tc_action *a, struct tcf_hashinfo *hinfo)
69 {
70         struct tcf_common *p;
71         int err = 0, index = -1,i = 0, s_i = 0, n_i = 0;
72         struct nlattr *nest;
73
74         read_lock_bh(hinfo->lock);
75
76         s_i = cb->args[0];
77
78         for (i = 0; i < (hinfo->hmask + 1); i++) {
79                 p = hinfo->htab[tcf_hash(i, hinfo->hmask)];
80
81                 for (; p; p = p->tcfc_next) {
82                         index++;
83                         if (index < s_i)
84                                 continue;
85                         a->priv = p;
86                         a->order = n_i;
87
88                         nest = nla_nest_start(skb, a->order);
89                         if (nest == NULL)
90                                 goto nla_put_failure;
91                         err = tcf_action_dump_1(skb, a, 0, 0);
92                         if (err < 0) {
93                                 index--;
94                                 nlmsg_trim(skb, nest);
95                                 goto done;
96                         }
97                         nla_nest_end(skb, nest);
98                         n_i++;
99                         if (n_i >= TCA_ACT_MAX_PRIO)
100                                 goto done;
101                 }
102         }
103 done:
104         read_unlock_bh(hinfo->lock);
105         if (n_i)
106                 cb->args[0] += n_i;
107         return n_i;
108
109 nla_put_failure:
110         nla_nest_cancel(skb, nest);
111         goto done;
112 }
113
114 static int tcf_del_walker(struct sk_buff *skb, struct tc_action *a,
115                           struct tcf_hashinfo *hinfo)
116 {
117         struct tcf_common *p, *s_p;
118         struct nlattr *nest;
119         int i= 0, n_i = 0;
120
121         nest = nla_nest_start(skb, a->order);
122         if (nest == NULL)
123                 goto nla_put_failure;
124         NLA_PUT_STRING(skb, TCA_KIND, a->ops->kind);
125         for (i = 0; i < (hinfo->hmask + 1); i++) {
126                 p = hinfo->htab[tcf_hash(i, hinfo->hmask)];
127
128                 while (p != NULL) {
129                         s_p = p->tcfc_next;
130                         if (ACT_P_DELETED == tcf_hash_release(p, 0, hinfo))
131                                  module_put(a->ops->owner);
132                         n_i++;
133                         p = s_p;
134                 }
135         }
136         NLA_PUT_U32(skb, TCA_FCNT, n_i);
137         nla_nest_end(skb, nest);
138
139         return n_i;
140 nla_put_failure:
141         nla_nest_cancel(skb, nest);
142         return -EINVAL;
143 }
144
145 int tcf_generic_walker(struct sk_buff *skb, struct netlink_callback *cb,
146                        int type, struct tc_action *a)
147 {
148         struct tcf_hashinfo *hinfo = a->ops->hinfo;
149
150         if (type == RTM_DELACTION) {
151                 return tcf_del_walker(skb, a, hinfo);
152         } else if (type == RTM_GETACTION) {
153                 return tcf_dump_walker(skb, cb, a, hinfo);
154         } else {
155                 printk("tcf_generic_walker: unknown action %d\n", type);
156                 return -EINVAL;
157         }
158 }
159 EXPORT_SYMBOL(tcf_generic_walker);
160
161 struct tcf_common *tcf_hash_lookup(u32 index, struct tcf_hashinfo *hinfo)
162 {
163         struct tcf_common *p;
164
165         read_lock_bh(hinfo->lock);
166         for (p = hinfo->htab[tcf_hash(index, hinfo->hmask)]; p;
167              p = p->tcfc_next) {
168                 if (p->tcfc_index == index)
169                         break;
170         }
171         read_unlock_bh(hinfo->lock);
172
173         return p;
174 }
175 EXPORT_SYMBOL(tcf_hash_lookup);
176
177 u32 tcf_hash_new_index(u32 *idx_gen, struct tcf_hashinfo *hinfo)
178 {
179         u32 val = *idx_gen;
180
181         do {
182                 if (++val == 0)
183                         val = 1;
184         } while (tcf_hash_lookup(val, hinfo));
185
186         return (*idx_gen = val);
187 }
188 EXPORT_SYMBOL(tcf_hash_new_index);
189
190 int tcf_hash_search(struct tc_action *a, u32 index)
191 {
192         struct tcf_hashinfo *hinfo = a->ops->hinfo;
193         struct tcf_common *p = tcf_hash_lookup(index, hinfo);
194
195         if (p) {
196                 a->priv = p;
197                 return 1;
198         }
199         return 0;
200 }
201 EXPORT_SYMBOL(tcf_hash_search);
202
203 struct tcf_common *tcf_hash_check(u32 index, struct tc_action *a, int bind,
204                                   struct tcf_hashinfo *hinfo)
205 {
206         struct tcf_common *p = NULL;
207         if (index && (p = tcf_hash_lookup(index, hinfo)) != NULL) {
208                 if (bind) {
209                         p->tcfc_bindcnt++;
210                         p->tcfc_refcnt++;
211                 }
212                 a->priv = p;
213         }
214         return p;
215 }
216 EXPORT_SYMBOL(tcf_hash_check);
217
218 struct tcf_common *tcf_hash_create(u32 index, struct nlattr *est, struct tc_action *a, int size, int bind, u32 *idx_gen, struct tcf_hashinfo *hinfo)
219 {
220         struct tcf_common *p = kzalloc(size, GFP_KERNEL);
221
222         if (unlikely(!p))
223                 return p;
224         p->tcfc_refcnt = 1;
225         if (bind)
226                 p->tcfc_bindcnt = 1;
227
228         spin_lock_init(&p->tcfc_lock);
229         p->tcfc_index = index ? index : tcf_hash_new_index(idx_gen, hinfo);
230         p->tcfc_tm.install = jiffies;
231         p->tcfc_tm.lastuse = jiffies;
232         if (est)
233                 gen_new_estimator(&p->tcfc_bstats, &p->tcfc_rate_est,
234                                   &p->tcfc_lock, est);
235         a->priv = (void *) p;
236         return p;
237 }
238 EXPORT_SYMBOL(tcf_hash_create);
239
240 void tcf_hash_insert(struct tcf_common *p, struct tcf_hashinfo *hinfo)
241 {
242         unsigned int h = tcf_hash(p->tcfc_index, hinfo->hmask);
243
244         write_lock_bh(hinfo->lock);
245         p->tcfc_next = hinfo->htab[h];
246         hinfo->htab[h] = p;
247         write_unlock_bh(hinfo->lock);
248 }
249 EXPORT_SYMBOL(tcf_hash_insert);
250
251 static struct tc_action_ops *act_base = NULL;
252 static DEFINE_RWLOCK(act_mod_lock);
253
254 int tcf_register_action(struct tc_action_ops *act)
255 {
256         struct tc_action_ops *a, **ap;
257
258         write_lock(&act_mod_lock);
259         for (ap = &act_base; (a = *ap) != NULL; ap = &a->next) {
260                 if (act->type == a->type || (strcmp(act->kind, a->kind) == 0)) {
261                         write_unlock(&act_mod_lock);
262                         return -EEXIST;
263                 }
264         }
265         act->next = NULL;
266         *ap = act;
267         write_unlock(&act_mod_lock);
268         return 0;
269 }
270 EXPORT_SYMBOL(tcf_register_action);
271
272 int tcf_unregister_action(struct tc_action_ops *act)
273 {
274         struct tc_action_ops *a, **ap;
275         int err = -ENOENT;
276
277         write_lock(&act_mod_lock);
278         for (ap = &act_base; (a = *ap) != NULL; ap = &a->next)
279                 if (a == act)
280                         break;
281         if (a) {
282                 *ap = a->next;
283                 a->next = NULL;
284                 err = 0;
285         }
286         write_unlock(&act_mod_lock);
287         return err;
288 }
289 EXPORT_SYMBOL(tcf_unregister_action);
290
291 /* lookup by name */
292 static struct tc_action_ops *tc_lookup_action_n(char *kind)
293 {
294         struct tc_action_ops *a = NULL;
295
296         if (kind) {
297                 read_lock(&act_mod_lock);
298                 for (a = act_base; a; a = a->next) {
299                         if (strcmp(kind, a->kind) == 0) {
300                                 if (!try_module_get(a->owner)) {
301                                         read_unlock(&act_mod_lock);
302                                         return NULL;
303                                 }
304                                 break;
305                         }
306                 }
307                 read_unlock(&act_mod_lock);
308         }
309         return a;
310 }
311
312 /* lookup by nlattr */
313 static struct tc_action_ops *tc_lookup_action(struct nlattr *kind)
314 {
315         struct tc_action_ops *a = NULL;
316
317         if (kind) {
318                 read_lock(&act_mod_lock);
319                 for (a = act_base; a; a = a->next) {
320                         if (nla_strcmp(kind, a->kind) == 0) {
321                                 if (!try_module_get(a->owner)) {
322                                         read_unlock(&act_mod_lock);
323                                         return NULL;
324                                 }
325                                 break;
326                         }
327                 }
328                 read_unlock(&act_mod_lock);
329         }
330         return a;
331 }
332
333 #if 0
334 /* lookup by id */
335 static struct tc_action_ops *tc_lookup_action_id(u32 type)
336 {
337         struct tc_action_ops *a = NULL;
338
339         if (type) {
340                 read_lock(&act_mod_lock);
341                 for (a = act_base; a; a = a->next) {
342                         if (a->type == type) {
343                                 if (!try_module_get(a->owner)) {
344                                         read_unlock(&act_mod_lock);
345                                         return NULL;
346                                 }
347                                 break;
348                         }
349                 }
350                 read_unlock(&act_mod_lock);
351         }
352         return a;
353 }
354 #endif
355
356 int tcf_action_exec(struct sk_buff *skb, struct tc_action *act,
357                     struct tcf_result *res)
358 {
359         struct tc_action *a;
360         int ret = -1;
361
362         if (skb->tc_verd & TC_NCLS) {
363                 skb->tc_verd = CLR_TC_NCLS(skb->tc_verd);
364                 ret = TC_ACT_OK;
365                 goto exec_done;
366         }
367         while ((a = act) != NULL) {
368 repeat:
369                 if (a->ops && a->ops->act) {
370                         ret = a->ops->act(skb, a, res);
371                         if (TC_MUNGED & skb->tc_verd) {
372                                 /* copied already, allow trampling */
373                                 skb->tc_verd = SET_TC_OK2MUNGE(skb->tc_verd);
374                                 skb->tc_verd = CLR_TC_MUNGED(skb->tc_verd);
375                         }
376                         if (ret == TC_ACT_REPEAT)
377                                 goto repeat;    /* we need a ttl - JHS */
378                         if (ret != TC_ACT_PIPE)
379                                 goto exec_done;
380                 }
381                 act = a->next;
382         }
383 exec_done:
384         return ret;
385 }
386 EXPORT_SYMBOL(tcf_action_exec);
387
388 void tcf_action_destroy(struct tc_action *act, int bind)
389 {
390         struct tc_action *a;
391
392         for (a = act; a; a = act) {
393                 if (a->ops && a->ops->cleanup) {
394                         if (a->ops->cleanup(a, bind) == ACT_P_DELETED)
395                                 module_put(a->ops->owner);
396                         act = act->next;
397                         kfree(a);
398                 } else { /*FIXME: Remove later - catch insertion bugs*/
399                         printk("tcf_action_destroy: BUG? destroying NULL ops\n");
400                         act = act->next;
401                         kfree(a);
402                 }
403         }
404 }
405
406 int
407 tcf_action_dump_old(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
408 {
409         int err = -EINVAL;
410
411         if (a->ops == NULL || a->ops->dump == NULL)
412                 return err;
413         return a->ops->dump(skb, a, bind, ref);
414 }
415
416 int
417 tcf_action_dump_1(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
418 {
419         int err = -EINVAL;
420         unsigned char *b = skb_tail_pointer(skb);
421         struct nlattr *nest;
422
423         if (a->ops == NULL || a->ops->dump == NULL)
424                 return err;
425
426         NLA_PUT_STRING(skb, TCA_KIND, a->ops->kind);
427         if (tcf_action_copy_stats(skb, a, 0))
428                 goto nla_put_failure;
429         nest = nla_nest_start(skb, TCA_OPTIONS);
430         if (nest == NULL)
431                 goto nla_put_failure;
432         if ((err = tcf_action_dump_old(skb, a, bind, ref)) > 0) {
433                 nla_nest_end(skb, nest);
434                 return err;
435         }
436
437 nla_put_failure:
438         nlmsg_trim(skb, b);
439         return -1;
440 }
441 EXPORT_SYMBOL(tcf_action_dump_1);
442
443 int
444 tcf_action_dump(struct sk_buff *skb, struct tc_action *act, int bind, int ref)
445 {
446         struct tc_action *a;
447         int err = -EINVAL;
448         struct nlattr *nest;
449
450         while ((a = act) != NULL) {
451                 act = a->next;
452                 nest = nla_nest_start(skb, a->order);
453                 if (nest == NULL)
454                         goto nla_put_failure;
455                 err = tcf_action_dump_1(skb, a, bind, ref);
456                 if (err < 0)
457                         goto errout;
458                 nla_nest_end(skb, nest);
459         }
460
461         return 0;
462
463 nla_put_failure:
464         err = -EINVAL;
465 errout:
466         nla_nest_cancel(skb, nest);
467         return err;
468 }
469
470 struct tc_action *tcf_action_init_1(struct nlattr *nla, struct nlattr *est,
471                                     char *name, int ovr, int bind)
472 {
473         struct tc_action *a;
474         struct tc_action_ops *a_o;
475         char act_name[IFNAMSIZ];
476         struct nlattr *tb[TCA_ACT_MAX+1];
477         struct nlattr *kind;
478         int err;
479
480         if (name == NULL) {
481                 err = nla_parse_nested(tb, TCA_ACT_MAX, nla, NULL);
482                 if (err < 0)
483                         goto err_out;
484                 err = -EINVAL;
485                 kind = tb[TCA_ACT_KIND];
486                 if (kind == NULL)
487                         goto err_out;
488                 if (nla_strlcpy(act_name, kind, IFNAMSIZ) >= IFNAMSIZ)
489                         goto err_out;
490         } else {
491                 err = -EINVAL;
492                 if (strlcpy(act_name, name, IFNAMSIZ) >= IFNAMSIZ)
493                         goto err_out;
494         }
495
496         a_o = tc_lookup_action_n(act_name);
497         if (a_o == NULL) {
498 #ifdef CONFIG_KMOD
499                 rtnl_unlock();
500                 request_module("act_%s", act_name);
501                 rtnl_lock();
502
503                 a_o = tc_lookup_action_n(act_name);
504
505                 /* We dropped the RTNL semaphore in order to
506                  * perform the module load.  So, even if we
507                  * succeeded in loading the module we have to
508                  * tell the caller to replay the request.  We
509                  * indicate this using -EAGAIN.
510                  */
511                 if (a_o != NULL) {
512                         err = -EAGAIN;
513                         goto err_mod;
514                 }
515 #endif
516                 err = -ENOENT;
517                 goto err_out;
518         }
519
520         err = -ENOMEM;
521         a = kzalloc(sizeof(*a), GFP_KERNEL);
522         if (a == NULL)
523                 goto err_mod;
524
525         /* backward compatibility for policer */
526         if (name == NULL)
527                 err = a_o->init(tb[TCA_ACT_OPTIONS], est, a, ovr, bind);
528         else
529                 err = a_o->init(nla, est, a, ovr, bind);
530         if (err < 0)
531                 goto err_free;
532
533         /* module count goes up only when brand new policy is created
534            if it exists and is only bound to in a_o->init() then
535            ACT_P_CREATED is not returned (a zero is).
536         */
537         if (err != ACT_P_CREATED)
538                 module_put(a_o->owner);
539         a->ops = a_o;
540
541         return a;
542
543 err_free:
544         kfree(a);
545 err_mod:
546         module_put(a_o->owner);
547 err_out:
548         return ERR_PTR(err);
549 }
550
551 struct tc_action *tcf_action_init(struct nlattr *nla, struct nlattr *est,
552                                   char *name, int ovr, int bind)
553 {
554         struct nlattr *tb[TCA_ACT_MAX_PRIO+1];
555         struct tc_action *head = NULL, *act, *act_prev = NULL;
556         int err;
557         int i;
558
559         err = nla_parse_nested(tb, TCA_ACT_MAX_PRIO, nla, NULL);
560         if (err < 0)
561                 return ERR_PTR(err);
562
563         for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
564                 act = tcf_action_init_1(tb[i], est, name, ovr, bind);
565                 if (IS_ERR(act))
566                         goto err;
567                 act->order = i;
568
569                 if (head == NULL)
570                         head = act;
571                 else
572                         act_prev->next = act;
573                 act_prev = act;
574         }
575         return head;
576
577 err:
578         if (head != NULL)
579                 tcf_action_destroy(head, bind);
580         return act;
581 }
582
583 int tcf_action_copy_stats(struct sk_buff *skb, struct tc_action *a,
584                           int compat_mode)
585 {
586         int err = 0;
587         struct gnet_dump d;
588         struct tcf_act_hdr *h = a->priv;
589
590         if (h == NULL)
591                 goto errout;
592
593         /* compat_mode being true specifies a call that is supposed
594          * to add additional backward compatiblity statistic TLVs.
595          */
596         if (compat_mode) {
597                 if (a->type == TCA_OLD_COMPAT)
598                         err = gnet_stats_start_copy_compat(skb, 0,
599                                 TCA_STATS, TCA_XSTATS, &h->tcf_lock, &d);
600                 else
601                         return 0;
602         } else
603                 err = gnet_stats_start_copy(skb, TCA_ACT_STATS,
604                                             &h->tcf_lock, &d);
605
606         if (err < 0)
607                 goto errout;
608
609         if (a->ops != NULL && a->ops->get_stats != NULL)
610                 if (a->ops->get_stats(skb, a) < 0)
611                         goto errout;
612
613         if (gnet_stats_copy_basic(&d, &h->tcf_bstats) < 0 ||
614             gnet_stats_copy_rate_est(&d, &h->tcf_rate_est) < 0 ||
615             gnet_stats_copy_queue(&d, &h->tcf_qstats) < 0)
616                 goto errout;
617
618         if (gnet_stats_finish_copy(&d) < 0)
619                 goto errout;
620
621         return 0;
622
623 errout:
624         return -1;
625 }
626
627 static int
628 tca_get_fill(struct sk_buff *skb, struct tc_action *a, u32 pid, u32 seq,
629              u16 flags, int event, int bind, int ref)
630 {
631         struct tcamsg *t;
632         struct nlmsghdr *nlh;
633         unsigned char *b = skb_tail_pointer(skb);
634         struct nlattr *nest;
635
636         nlh = NLMSG_NEW(skb, pid, seq, event, sizeof(*t), flags);
637
638         t = NLMSG_DATA(nlh);
639         t->tca_family = AF_UNSPEC;
640         t->tca__pad1 = 0;
641         t->tca__pad2 = 0;
642
643         nest = nla_nest_start(skb, TCA_ACT_TAB);
644         if (nest == NULL)
645                 goto nla_put_failure;
646
647         if (tcf_action_dump(skb, a, bind, ref) < 0)
648                 goto nla_put_failure;
649
650         nla_nest_end(skb, nest);
651
652         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
653         return skb->len;
654
655 nla_put_failure:
656 nlmsg_failure:
657         nlmsg_trim(skb, b);
658         return -1;
659 }
660
661 static int
662 act_get_notify(u32 pid, struct nlmsghdr *n, struct tc_action *a, int event)
663 {
664         struct sk_buff *skb;
665
666         skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
667         if (!skb)
668                 return -ENOBUFS;
669         if (tca_get_fill(skb, a, pid, n->nlmsg_seq, 0, event, 0, 0) <= 0) {
670                 kfree_skb(skb);
671                 return -EINVAL;
672         }
673
674         return rtnl_unicast(skb, &init_net, pid);
675 }
676
677 static struct tc_action *
678 tcf_action_get_1(struct nlattr *nla, struct nlmsghdr *n, u32 pid)
679 {
680         struct nlattr *tb[TCA_ACT_MAX+1];
681         struct tc_action *a;
682         int index;
683         int err;
684
685         err = nla_parse_nested(tb, TCA_ACT_MAX, nla, NULL);
686         if (err < 0)
687                 goto err_out;
688
689         err = -EINVAL;
690         if (tb[TCA_ACT_INDEX] == NULL ||
691             nla_len(tb[TCA_ACT_INDEX]) < sizeof(index))
692                 goto err_out;
693         index = nla_get_u32(tb[TCA_ACT_INDEX]);
694
695         err = -ENOMEM;
696         a = kzalloc(sizeof(struct tc_action), GFP_KERNEL);
697         if (a == NULL)
698                 goto err_out;
699
700         err = -EINVAL;
701         a->ops = tc_lookup_action(tb[TCA_ACT_KIND]);
702         if (a->ops == NULL)
703                 goto err_free;
704         if (a->ops->lookup == NULL)
705                 goto err_mod;
706         err = -ENOENT;
707         if (a->ops->lookup(a, index) == 0)
708                 goto err_mod;
709
710         module_put(a->ops->owner);
711         return a;
712
713 err_mod:
714         module_put(a->ops->owner);
715 err_free:
716         kfree(a);
717 err_out:
718         return ERR_PTR(err);
719 }
720
721 static void cleanup_a(struct tc_action *act)
722 {
723         struct tc_action *a;
724
725         for (a = act; a; a = act) {
726                 act = a->next;
727                 kfree(a);
728         }
729 }
730
731 static struct tc_action *create_a(int i)
732 {
733         struct tc_action *act;
734
735         act = kzalloc(sizeof(*act), GFP_KERNEL);
736         if (act == NULL) {
737                 printk("create_a: failed to alloc!\n");
738                 return NULL;
739         }
740         act->order = i;
741         return act;
742 }
743
744 static int tca_action_flush(struct nlattr *nla, struct nlmsghdr *n, u32 pid)
745 {
746         struct sk_buff *skb;
747         unsigned char *b;
748         struct nlmsghdr *nlh;
749         struct tcamsg *t;
750         struct netlink_callback dcb;
751         struct nlattr *nest;
752         struct nlattr *tb[TCA_ACT_MAX+1];
753         struct nlattr *kind;
754         struct tc_action *a = create_a(0);
755         int err = -EINVAL;
756
757         if (a == NULL) {
758                 printk("tca_action_flush: couldnt create tc_action\n");
759                 return err;
760         }
761
762         skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
763         if (!skb) {
764                 printk("tca_action_flush: failed skb alloc\n");
765                 kfree(a);
766                 return -ENOBUFS;
767         }
768
769         b = skb_tail_pointer(skb);
770
771         err = nla_parse_nested(tb, TCA_ACT_MAX, nla, NULL);
772         if (err < 0)
773                 goto err_out;
774
775         err = -EINVAL;
776         kind = tb[TCA_ACT_KIND];
777         a->ops = tc_lookup_action(kind);
778         if (a->ops == NULL)
779                 goto err_out;
780
781         nlh = NLMSG_PUT(skb, pid, n->nlmsg_seq, RTM_DELACTION, sizeof(*t));
782         t = NLMSG_DATA(nlh);
783         t->tca_family = AF_UNSPEC;
784         t->tca__pad1 = 0;
785         t->tca__pad2 = 0;
786
787         nest = nla_nest_start(skb, TCA_ACT_TAB);
788         if (nest == NULL)
789                 goto nla_put_failure;
790
791         err = a->ops->walk(skb, &dcb, RTM_DELACTION, a);
792         if (err < 0)
793                 goto nla_put_failure;
794
795         nla_nest_end(skb, nest);
796
797         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
798         nlh->nlmsg_flags |= NLM_F_ROOT;
799         module_put(a->ops->owner);
800         kfree(a);
801         err = rtnetlink_send(skb, &init_net, pid, RTNLGRP_TC, n->nlmsg_flags&NLM_F_ECHO);
802         if (err > 0)
803                 return 0;
804
805         return err;
806
807 nla_put_failure:
808 nlmsg_failure:
809         module_put(a->ops->owner);
810 err_out:
811         kfree_skb(skb);
812         kfree(a);
813         return err;
814 }
815
816 static int
817 tca_action_gd(struct nlattr *nla, struct nlmsghdr *n, u32 pid, int event)
818 {
819         int i, ret;
820         struct nlattr *tb[TCA_ACT_MAX_PRIO+1];
821         struct tc_action *head = NULL, *act, *act_prev = NULL;
822
823         ret = nla_parse_nested(tb, TCA_ACT_MAX_PRIO, nla, NULL);
824         if (ret < 0)
825                 return ret;
826
827         if (event == RTM_DELACTION && n->nlmsg_flags&NLM_F_ROOT) {
828                 if (tb[0] != NULL && tb[1] == NULL)
829                         return tca_action_flush(tb[0], n, pid);
830         }
831
832         for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
833                 act = tcf_action_get_1(tb[i], n, pid);
834                 if (IS_ERR(act)) {
835                         ret = PTR_ERR(act);
836                         goto err;
837                 }
838                 act->order = i;
839
840                 if (head == NULL)
841                         head = act;
842                 else
843                         act_prev->next = act;
844                 act_prev = act;
845         }
846
847         if (event == RTM_GETACTION)
848                 ret = act_get_notify(pid, n, head, event);
849         else { /* delete */
850                 struct sk_buff *skb;
851
852                 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
853                 if (!skb) {
854                         ret = -ENOBUFS;
855                         goto err;
856                 }
857
858                 if (tca_get_fill(skb, head, pid, n->nlmsg_seq, 0, event,
859                                  0, 1) <= 0) {
860                         kfree_skb(skb);
861                         ret = -EINVAL;
862                         goto err;
863                 }
864
865                 /* now do the delete */
866                 tcf_action_destroy(head, 0);
867                 ret = rtnetlink_send(skb, &init_net, pid, RTNLGRP_TC,
868                                      n->nlmsg_flags&NLM_F_ECHO);
869                 if (ret > 0)
870                         return 0;
871                 return ret;
872         }
873 err:
874         cleanup_a(head);
875         return ret;
876 }
877
878 static int tcf_add_notify(struct tc_action *a, u32 pid, u32 seq, int event,
879                           u16 flags)
880 {
881         struct tcamsg *t;
882         struct nlmsghdr *nlh;
883         struct sk_buff *skb;
884         struct nlattr *nest;
885         unsigned char *b;
886         int err = 0;
887
888         skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
889         if (!skb)
890                 return -ENOBUFS;
891
892         b = skb_tail_pointer(skb);
893
894         nlh = NLMSG_NEW(skb, pid, seq, event, sizeof(*t), flags);
895         t = NLMSG_DATA(nlh);
896         t->tca_family = AF_UNSPEC;
897         t->tca__pad1 = 0;
898         t->tca__pad2 = 0;
899
900         nest = nla_nest_start(skb, TCA_ACT_TAB);
901         if (nest == NULL)
902                 goto nla_put_failure;
903
904         if (tcf_action_dump(skb, a, 0, 0) < 0)
905                 goto nla_put_failure;
906
907         nla_nest_end(skb, nest);
908
909         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
910         NETLINK_CB(skb).dst_group = RTNLGRP_TC;
911
912         err = rtnetlink_send(skb, &init_net, pid, RTNLGRP_TC, flags&NLM_F_ECHO);
913         if (err > 0)
914                 err = 0;
915         return err;
916
917 nla_put_failure:
918 nlmsg_failure:
919         kfree_skb(skb);
920         return -1;
921 }
922
923
924 static int
925 tcf_action_add(struct nlattr *nla, struct nlmsghdr *n, u32 pid, int ovr)
926 {
927         int ret = 0;
928         struct tc_action *act;
929         struct tc_action *a;
930         u32 seq = n->nlmsg_seq;
931
932         act = tcf_action_init(nla, NULL, NULL, ovr, 0);
933         if (act == NULL)
934                 goto done;
935         if (IS_ERR(act)) {
936                 ret = PTR_ERR(act);
937                 goto done;
938         }
939
940         /* dump then free all the actions after update; inserted policy
941          * stays intact
942          * */
943         ret = tcf_add_notify(act, pid, seq, RTM_NEWACTION, n->nlmsg_flags);
944         for (a = act; a; a = act) {
945                 act = a->next;
946                 kfree(a);
947         }
948 done:
949         return ret;
950 }
951
952 static int tc_ctl_action(struct sk_buff *skb, struct nlmsghdr *n, void *arg)
953 {
954         struct net *net = skb->sk->sk_net;
955         struct nlattr *tca[TCA_ACT_MAX + 1];
956         u32 pid = skb ? NETLINK_CB(skb).pid : 0;
957         int ret = 0, ovr = 0;
958
959         if (net != &init_net)
960                 return -EINVAL;
961
962         ret = nlmsg_parse(n, sizeof(struct tcamsg), tca, TCA_ACT_MAX, NULL);
963         if (ret < 0)
964                 return ret;
965
966         if (tca[TCA_ACT_TAB] == NULL) {
967                 printk("tc_ctl_action: received NO action attribs\n");
968                 return -EINVAL;
969         }
970
971         /* n->nlmsg_flags&NLM_F_CREATE
972          * */
973         switch (n->nlmsg_type) {
974         case RTM_NEWACTION:
975                 /* we are going to assume all other flags
976                  * imply create only if it doesnt exist
977                  * Note that CREATE | EXCL implies that
978                  * but since we want avoid ambiguity (eg when flags
979                  * is zero) then just set this
980                  */
981                 if (n->nlmsg_flags&NLM_F_REPLACE)
982                         ovr = 1;
983 replay:
984                 ret = tcf_action_add(tca[TCA_ACT_TAB], n, pid, ovr);
985                 if (ret == -EAGAIN)
986                         goto replay;
987                 break;
988         case RTM_DELACTION:
989                 ret = tca_action_gd(tca[TCA_ACT_TAB], n, pid, RTM_DELACTION);
990                 break;
991         case RTM_GETACTION:
992                 ret = tca_action_gd(tca[TCA_ACT_TAB], n, pid, RTM_GETACTION);
993                 break;
994         default:
995                 BUG();
996         }
997
998         return ret;
999 }
1000
1001 static struct nlattr *
1002 find_dump_kind(struct nlmsghdr *n)
1003 {
1004         struct nlattr *tb1, *tb2[TCA_ACT_MAX+1];
1005         struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
1006         struct nlattr *nla[TCAA_MAX + 1];
1007         struct nlattr *kind;
1008
1009         if (nlmsg_parse(n, sizeof(struct tcamsg), nla, TCAA_MAX, NULL) < 0)
1010                 return NULL;
1011         tb1 = nla[TCA_ACT_TAB];
1012         if (tb1 == NULL)
1013                 return NULL;
1014
1015         if (nla_parse(tb, TCA_ACT_MAX_PRIO, nla_data(tb1),
1016                       NLMSG_ALIGN(nla_len(tb1)), NULL) < 0)
1017                 return NULL;
1018
1019         if (tb[1] == NULL)
1020                 return NULL;
1021         if (nla_parse(tb2, TCA_ACT_MAX, nla_data(tb[1]),
1022                       nla_len(tb[1]), NULL) < 0)
1023                 return NULL;
1024         kind = tb2[TCA_ACT_KIND];
1025
1026         return kind;
1027 }
1028
1029 static int
1030 tc_dump_action(struct sk_buff *skb, struct netlink_callback *cb)
1031 {
1032         struct net *net = skb->sk->sk_net;
1033         struct nlmsghdr *nlh;
1034         unsigned char *b = skb_tail_pointer(skb);
1035         struct nlattr *nest;
1036         struct tc_action_ops *a_o;
1037         struct tc_action a;
1038         int ret = 0;
1039         struct tcamsg *t = (struct tcamsg *) NLMSG_DATA(cb->nlh);
1040         struct nlattr *kind = find_dump_kind(cb->nlh);
1041
1042         if (net != &init_net)
1043                 return 0;
1044
1045         if (kind == NULL) {
1046                 printk("tc_dump_action: action bad kind\n");
1047                 return 0;
1048         }
1049
1050         a_o = tc_lookup_action(kind);
1051         if (a_o == NULL) {
1052                 return 0;
1053         }
1054
1055         memset(&a, 0, sizeof(struct tc_action));
1056         a.ops = a_o;
1057
1058         if (a_o->walk == NULL) {
1059                 printk("tc_dump_action: %s !capable of dumping table\n", a_o->kind);
1060                 goto nla_put_failure;
1061         }
1062
1063         nlh = NLMSG_PUT(skb, NETLINK_CB(cb->skb).pid, cb->nlh->nlmsg_seq,
1064                         cb->nlh->nlmsg_type, sizeof(*t));
1065         t = NLMSG_DATA(nlh);
1066         t->tca_family = AF_UNSPEC;
1067         t->tca__pad1 = 0;
1068         t->tca__pad2 = 0;
1069
1070         nest = nla_nest_start(skb, TCA_ACT_TAB);
1071         if (nest == NULL)
1072                 goto nla_put_failure;
1073
1074         ret = a_o->walk(skb, cb, RTM_GETACTION, &a);
1075         if (ret < 0)
1076                 goto nla_put_failure;
1077
1078         if (ret > 0) {
1079                 nla_nest_end(skb, nest);
1080                 ret = skb->len;
1081         } else
1082                 nla_nest_cancel(skb, nest);
1083
1084         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1085         if (NETLINK_CB(cb->skb).pid && ret)
1086                 nlh->nlmsg_flags |= NLM_F_MULTI;
1087         module_put(a_o->owner);
1088         return skb->len;
1089
1090 nla_put_failure:
1091 nlmsg_failure:
1092         module_put(a_o->owner);
1093         nlmsg_trim(skb, b);
1094         return skb->len;
1095 }
1096
1097 static int __init tc_action_init(void)
1098 {
1099         rtnl_register(PF_UNSPEC, RTM_NEWACTION, tc_ctl_action, NULL);
1100         rtnl_register(PF_UNSPEC, RTM_DELACTION, tc_ctl_action, NULL);
1101         rtnl_register(PF_UNSPEC, RTM_GETACTION, tc_ctl_action, tc_dump_action);
1102
1103         return 0;
1104 }
1105
1106 subsys_initcall(tc_action_init);