Merge branch 'iommu-fixes-2.6.28' of git://git.kernel.org/pub/scm/linux/kernel/git...
[linux-2.6] / 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         WARN_ON(1);
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                 a->priv = p;
212         }
213         return p;
214 }
215 EXPORT_SYMBOL(tcf_hash_check);
216
217 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)
218 {
219         struct tcf_common *p = kzalloc(size, GFP_KERNEL);
220
221         if (unlikely(!p))
222                 return p;
223         p->tcfc_refcnt = 1;
224         if (bind)
225                 p->tcfc_bindcnt = 1;
226
227         spin_lock_init(&p->tcfc_lock);
228         p->tcfc_index = index ? index : tcf_hash_new_index(idx_gen, hinfo);
229         p->tcfc_tm.install = jiffies;
230         p->tcfc_tm.lastuse = jiffies;
231         if (est)
232                 gen_new_estimator(&p->tcfc_bstats, &p->tcfc_rate_est,
233                                   &p->tcfc_lock, est);
234         a->priv = (void *) p;
235         return p;
236 }
237 EXPORT_SYMBOL(tcf_hash_create);
238
239 void tcf_hash_insert(struct tcf_common *p, struct tcf_hashinfo *hinfo)
240 {
241         unsigned int h = tcf_hash(p->tcfc_index, hinfo->hmask);
242
243         write_lock_bh(hinfo->lock);
244         p->tcfc_next = hinfo->htab[h];
245         hinfo->htab[h] = p;
246         write_unlock_bh(hinfo->lock);
247 }
248 EXPORT_SYMBOL(tcf_hash_insert);
249
250 static struct tc_action_ops *act_base = NULL;
251 static DEFINE_RWLOCK(act_mod_lock);
252
253 int tcf_register_action(struct tc_action_ops *act)
254 {
255         struct tc_action_ops *a, **ap;
256
257         write_lock(&act_mod_lock);
258         for (ap = &act_base; (a = *ap) != NULL; ap = &a->next) {
259                 if (act->type == a->type || (strcmp(act->kind, a->kind) == 0)) {
260                         write_unlock(&act_mod_lock);
261                         return -EEXIST;
262                 }
263         }
264         act->next = NULL;
265         *ap = act;
266         write_unlock(&act_mod_lock);
267         return 0;
268 }
269 EXPORT_SYMBOL(tcf_register_action);
270
271 int tcf_unregister_action(struct tc_action_ops *act)
272 {
273         struct tc_action_ops *a, **ap;
274         int err = -ENOENT;
275
276         write_lock(&act_mod_lock);
277         for (ap = &act_base; (a = *ap) != NULL; ap = &a->next)
278                 if (a == act)
279                         break;
280         if (a) {
281                 *ap = a->next;
282                 a->next = NULL;
283                 err = 0;
284         }
285         write_unlock(&act_mod_lock);
286         return err;
287 }
288 EXPORT_SYMBOL(tcf_unregister_action);
289
290 /* lookup by name */
291 static struct tc_action_ops *tc_lookup_action_n(char *kind)
292 {
293         struct tc_action_ops *a = NULL;
294
295         if (kind) {
296                 read_lock(&act_mod_lock);
297                 for (a = act_base; a; a = a->next) {
298                         if (strcmp(kind, a->kind) == 0) {
299                                 if (!try_module_get(a->owner)) {
300                                         read_unlock(&act_mod_lock);
301                                         return NULL;
302                                 }
303                                 break;
304                         }
305                 }
306                 read_unlock(&act_mod_lock);
307         }
308         return a;
309 }
310
311 /* lookup by nlattr */
312 static struct tc_action_ops *tc_lookup_action(struct nlattr *kind)
313 {
314         struct tc_action_ops *a = NULL;
315
316         if (kind) {
317                 read_lock(&act_mod_lock);
318                 for (a = act_base; a; a = a->next) {
319                         if (nla_strcmp(kind, a->kind) == 0) {
320                                 if (!try_module_get(a->owner)) {
321                                         read_unlock(&act_mod_lock);
322                                         return NULL;
323                                 }
324                                 break;
325                         }
326                 }
327                 read_unlock(&act_mod_lock);
328         }
329         return a;
330 }
331
332 #if 0
333 /* lookup by id */
334 static struct tc_action_ops *tc_lookup_action_id(u32 type)
335 {
336         struct tc_action_ops *a = NULL;
337
338         if (type) {
339                 read_lock(&act_mod_lock);
340                 for (a = act_base; a; a = a->next) {
341                         if (a->type == type) {
342                                 if (!try_module_get(a->owner)) {
343                                         read_unlock(&act_mod_lock);
344                                         return NULL;
345                                 }
346                                 break;
347                         }
348                 }
349                 read_unlock(&act_mod_lock);
350         }
351         return a;
352 }
353 #endif
354
355 int tcf_action_exec(struct sk_buff *skb, struct tc_action *act,
356                     struct tcf_result *res)
357 {
358         struct tc_action *a;
359         int ret = -1;
360
361         if (skb->tc_verd & TC_NCLS) {
362                 skb->tc_verd = CLR_TC_NCLS(skb->tc_verd);
363                 ret = TC_ACT_OK;
364                 goto exec_done;
365         }
366         while ((a = act) != NULL) {
367 repeat:
368                 if (a->ops && a->ops->act) {
369                         ret = a->ops->act(skb, a, res);
370                         if (TC_MUNGED & skb->tc_verd) {
371                                 /* copied already, allow trampling */
372                                 skb->tc_verd = SET_TC_OK2MUNGE(skb->tc_verd);
373                                 skb->tc_verd = CLR_TC_MUNGED(skb->tc_verd);
374                         }
375                         if (ret == TC_ACT_REPEAT)
376                                 goto repeat;    /* we need a ttl - JHS */
377                         if (ret != TC_ACT_PIPE)
378                                 goto exec_done;
379                 }
380                 act = a->next;
381         }
382 exec_done:
383         return ret;
384 }
385 EXPORT_SYMBOL(tcf_action_exec);
386
387 void tcf_action_destroy(struct tc_action *act, int bind)
388 {
389         struct tc_action *a;
390
391         for (a = act; a; a = act) {
392                 if (a->ops && a->ops->cleanup) {
393                         if (a->ops->cleanup(a, bind) == ACT_P_DELETED)
394                                 module_put(a->ops->owner);
395                         act = act->next;
396                         kfree(a);
397                 } else { /*FIXME: Remove later - catch insertion bugs*/
398                         printk("tcf_action_destroy: BUG? destroying NULL ops\n");
399                         act = act->next;
400                         kfree(a);
401                 }
402         }
403 }
404
405 int
406 tcf_action_dump_old(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
407 {
408         int err = -EINVAL;
409
410         if (a->ops == NULL || a->ops->dump == NULL)
411                 return err;
412         return a->ops->dump(skb, a, bind, ref);
413 }
414
415 int
416 tcf_action_dump_1(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
417 {
418         int err = -EINVAL;
419         unsigned char *b = skb_tail_pointer(skb);
420         struct nlattr *nest;
421
422         if (a->ops == NULL || a->ops->dump == NULL)
423                 return err;
424
425         NLA_PUT_STRING(skb, TCA_KIND, a->ops->kind);
426         if (tcf_action_copy_stats(skb, a, 0))
427                 goto nla_put_failure;
428         nest = nla_nest_start(skb, TCA_OPTIONS);
429         if (nest == NULL)
430                 goto nla_put_failure;
431         if ((err = tcf_action_dump_old(skb, a, bind, ref)) > 0) {
432                 nla_nest_end(skb, nest);
433                 return err;
434         }
435
436 nla_put_failure:
437         nlmsg_trim(skb, b);
438         return -1;
439 }
440 EXPORT_SYMBOL(tcf_action_dump_1);
441
442 int
443 tcf_action_dump(struct sk_buff *skb, struct tc_action *act, int bind, int ref)
444 {
445         struct tc_action *a;
446         int err = -EINVAL;
447         struct nlattr *nest;
448
449         while ((a = act) != NULL) {
450                 act = a->next;
451                 nest = nla_nest_start(skb, a->order);
452                 if (nest == NULL)
453                         goto nla_put_failure;
454                 err = tcf_action_dump_1(skb, a, bind, ref);
455                 if (err < 0)
456                         goto errout;
457                 nla_nest_end(skb, nest);
458         }
459
460         return 0;
461
462 nla_put_failure:
463         err = -EINVAL;
464 errout:
465         nla_nest_cancel(skb, nest);
466         return err;
467 }
468
469 struct tc_action *tcf_action_init_1(struct nlattr *nla, struct nlattr *est,
470                                     char *name, int ovr, int bind)
471 {
472         struct tc_action *a;
473         struct tc_action_ops *a_o;
474         char act_name[IFNAMSIZ];
475         struct nlattr *tb[TCA_ACT_MAX+1];
476         struct nlattr *kind;
477         int err;
478
479         if (name == NULL) {
480                 err = nla_parse_nested(tb, TCA_ACT_MAX, nla, NULL);
481                 if (err < 0)
482                         goto err_out;
483                 err = -EINVAL;
484                 kind = tb[TCA_ACT_KIND];
485                 if (kind == NULL)
486                         goto err_out;
487                 if (nla_strlcpy(act_name, kind, IFNAMSIZ) >= IFNAMSIZ)
488                         goto err_out;
489         } else {
490                 err = -EINVAL;
491                 if (strlcpy(act_name, name, IFNAMSIZ) >= IFNAMSIZ)
492                         goto err_out;
493         }
494
495         a_o = tc_lookup_action_n(act_name);
496         if (a_o == NULL) {
497 #ifdef CONFIG_MODULES
498                 rtnl_unlock();
499                 request_module("act_%s", act_name);
500                 rtnl_lock();
501
502                 a_o = tc_lookup_action_n(act_name);
503
504                 /* We dropped the RTNL semaphore in order to
505                  * perform the module load.  So, even if we
506                  * succeeded in loading the module we have to
507                  * tell the caller to replay the request.  We
508                  * indicate this using -EAGAIN.
509                  */
510                 if (a_o != NULL) {
511                         err = -EAGAIN;
512                         goto err_mod;
513                 }
514 #endif
515                 err = -ENOENT;
516                 goto err_out;
517         }
518
519         err = -ENOMEM;
520         a = kzalloc(sizeof(*a), GFP_KERNEL);
521         if (a == NULL)
522                 goto err_mod;
523
524         /* backward compatibility for policer */
525         if (name == NULL)
526                 err = a_o->init(tb[TCA_ACT_OPTIONS], est, a, ovr, bind);
527         else
528                 err = a_o->init(nla, est, a, ovr, bind);
529         if (err < 0)
530                 goto err_free;
531
532         /* module count goes up only when brand new policy is created
533            if it exists and is only bound to in a_o->init() then
534            ACT_P_CREATED is not returned (a zero is).
535         */
536         if (err != ACT_P_CREATED)
537                 module_put(a_o->owner);
538         a->ops = a_o;
539
540         return a;
541
542 err_free:
543         kfree(a);
544 err_mod:
545         module_put(a_o->owner);
546 err_out:
547         return ERR_PTR(err);
548 }
549
550 struct tc_action *tcf_action_init(struct nlattr *nla, struct nlattr *est,
551                                   char *name, int ovr, int bind)
552 {
553         struct nlattr *tb[TCA_ACT_MAX_PRIO+1];
554         struct tc_action *head = NULL, *act, *act_prev = NULL;
555         int err;
556         int i;
557
558         err = nla_parse_nested(tb, TCA_ACT_MAX_PRIO, nla, NULL);
559         if (err < 0)
560                 return ERR_PTR(err);
561
562         for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
563                 act = tcf_action_init_1(tb[i], est, name, ovr, bind);
564                 if (IS_ERR(act))
565                         goto err;
566                 act->order = i;
567
568                 if (head == NULL)
569                         head = act;
570                 else
571                         act_prev->next = act;
572                 act_prev = act;
573         }
574         return head;
575
576 err:
577         if (head != NULL)
578                 tcf_action_destroy(head, bind);
579         return act;
580 }
581
582 int tcf_action_copy_stats(struct sk_buff *skb, struct tc_action *a,
583                           int compat_mode)
584 {
585         int err = 0;
586         struct gnet_dump d;
587         struct tcf_act_hdr *h = a->priv;
588
589         if (h == NULL)
590                 goto errout;
591
592         /* compat_mode being true specifies a call that is supposed
593          * to add additional backward compatiblity statistic TLVs.
594          */
595         if (compat_mode) {
596                 if (a->type == TCA_OLD_COMPAT)
597                         err = gnet_stats_start_copy_compat(skb, 0,
598                                 TCA_STATS, TCA_XSTATS, &h->tcf_lock, &d);
599                 else
600                         return 0;
601         } else
602                 err = gnet_stats_start_copy(skb, TCA_ACT_STATS,
603                                             &h->tcf_lock, &d);
604
605         if (err < 0)
606                 goto errout;
607
608         if (a->ops != NULL && a->ops->get_stats != NULL)
609                 if (a->ops->get_stats(skb, a) < 0)
610                         goto errout;
611
612         if (gnet_stats_copy_basic(&d, &h->tcf_bstats) < 0 ||
613             gnet_stats_copy_rate_est(&d, &h->tcf_rate_est) < 0 ||
614             gnet_stats_copy_queue(&d, &h->tcf_qstats) < 0)
615                 goto errout;
616
617         if (gnet_stats_finish_copy(&d) < 0)
618                 goto errout;
619
620         return 0;
621
622 errout:
623         return -1;
624 }
625
626 static int
627 tca_get_fill(struct sk_buff *skb, struct tc_action *a, u32 pid, u32 seq,
628              u16 flags, int event, int bind, int ref)
629 {
630         struct tcamsg *t;
631         struct nlmsghdr *nlh;
632         unsigned char *b = skb_tail_pointer(skb);
633         struct nlattr *nest;
634
635         nlh = NLMSG_NEW(skb, pid, seq, event, sizeof(*t), flags);
636
637         t = NLMSG_DATA(nlh);
638         t->tca_family = AF_UNSPEC;
639         t->tca__pad1 = 0;
640         t->tca__pad2 = 0;
641
642         nest = nla_nest_start(skb, TCA_ACT_TAB);
643         if (nest == NULL)
644                 goto nla_put_failure;
645
646         if (tcf_action_dump(skb, a, bind, ref) < 0)
647                 goto nla_put_failure;
648
649         nla_nest_end(skb, nest);
650
651         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
652         return skb->len;
653
654 nla_put_failure:
655 nlmsg_failure:
656         nlmsg_trim(skb, b);
657         return -1;
658 }
659
660 static int
661 act_get_notify(u32 pid, struct nlmsghdr *n, struct tc_action *a, int event)
662 {
663         struct sk_buff *skb;
664
665         skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
666         if (!skb)
667                 return -ENOBUFS;
668         if (tca_get_fill(skb, a, pid, n->nlmsg_seq, 0, event, 0, 0) <= 0) {
669                 kfree_skb(skb);
670                 return -EINVAL;
671         }
672
673         return rtnl_unicast(skb, &init_net, pid);
674 }
675
676 static struct tc_action *
677 tcf_action_get_1(struct nlattr *nla, struct nlmsghdr *n, u32 pid)
678 {
679         struct nlattr *tb[TCA_ACT_MAX+1];
680         struct tc_action *a;
681         int index;
682         int err;
683
684         err = nla_parse_nested(tb, TCA_ACT_MAX, nla, NULL);
685         if (err < 0)
686                 goto err_out;
687
688         err = -EINVAL;
689         if (tb[TCA_ACT_INDEX] == NULL ||
690             nla_len(tb[TCA_ACT_INDEX]) < sizeof(index))
691                 goto err_out;
692         index = nla_get_u32(tb[TCA_ACT_INDEX]);
693
694         err = -ENOMEM;
695         a = kzalloc(sizeof(struct tc_action), GFP_KERNEL);
696         if (a == NULL)
697                 goto err_out;
698
699         err = -EINVAL;
700         a->ops = tc_lookup_action(tb[TCA_ACT_KIND]);
701         if (a->ops == NULL)
702                 goto err_free;
703         if (a->ops->lookup == NULL)
704                 goto err_mod;
705         err = -ENOENT;
706         if (a->ops->lookup(a, index) == 0)
707                 goto err_mod;
708
709         module_put(a->ops->owner);
710         return a;
711
712 err_mod:
713         module_put(a->ops->owner);
714 err_free:
715         kfree(a);
716 err_out:
717         return ERR_PTR(err);
718 }
719
720 static void cleanup_a(struct tc_action *act)
721 {
722         struct tc_action *a;
723
724         for (a = act; a; a = act) {
725                 act = a->next;
726                 kfree(a);
727         }
728 }
729
730 static struct tc_action *create_a(int i)
731 {
732         struct tc_action *act;
733
734         act = kzalloc(sizeof(*act), GFP_KERNEL);
735         if (act == NULL) {
736                 printk("create_a: failed to alloc!\n");
737                 return NULL;
738         }
739         act->order = i;
740         return act;
741 }
742
743 static int tca_action_flush(struct nlattr *nla, struct nlmsghdr *n, u32 pid)
744 {
745         struct sk_buff *skb;
746         unsigned char *b;
747         struct nlmsghdr *nlh;
748         struct tcamsg *t;
749         struct netlink_callback dcb;
750         struct nlattr *nest;
751         struct nlattr *tb[TCA_ACT_MAX+1];
752         struct nlattr *kind;
753         struct tc_action *a = create_a(0);
754         int err = -ENOMEM;
755
756         if (a == NULL) {
757                 printk("tca_action_flush: couldnt create tc_action\n");
758                 return err;
759         }
760
761         skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
762         if (!skb) {
763                 printk("tca_action_flush: failed skb alloc\n");
764                 kfree(a);
765                 return err;
766         }
767
768         b = skb_tail_pointer(skb);
769
770         err = nla_parse_nested(tb, TCA_ACT_MAX, nla, NULL);
771         if (err < 0)
772                 goto err_out;
773
774         err = -EINVAL;
775         kind = tb[TCA_ACT_KIND];
776         a->ops = tc_lookup_action(kind);
777         if (a->ops == NULL)
778                 goto err_out;
779
780         nlh = NLMSG_PUT(skb, pid, n->nlmsg_seq, RTM_DELACTION, sizeof(*t));
781         t = NLMSG_DATA(nlh);
782         t->tca_family = AF_UNSPEC;
783         t->tca__pad1 = 0;
784         t->tca__pad2 = 0;
785
786         nest = nla_nest_start(skb, TCA_ACT_TAB);
787         if (nest == NULL)
788                 goto nla_put_failure;
789
790         err = a->ops->walk(skb, &dcb, RTM_DELACTION, a);
791         if (err < 0)
792                 goto nla_put_failure;
793         if (err == 0)
794                 goto noflush_out;
795
796         nla_nest_end(skb, nest);
797
798         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
799         nlh->nlmsg_flags |= NLM_F_ROOT;
800         module_put(a->ops->owner);
801         kfree(a);
802         err = rtnetlink_send(skb, &init_net, pid, RTNLGRP_TC, n->nlmsg_flags&NLM_F_ECHO);
803         if (err > 0)
804                 return 0;
805
806         return err;
807
808 nla_put_failure:
809 nlmsg_failure:
810         module_put(a->ops->owner);
811 err_out:
812 noflush_out:
813         kfree_skb(skb);
814         kfree(a);
815         return err;
816 }
817
818 static int
819 tca_action_gd(struct nlattr *nla, struct nlmsghdr *n, u32 pid, int event)
820 {
821         int i, ret;
822         struct nlattr *tb[TCA_ACT_MAX_PRIO+1];
823         struct tc_action *head = NULL, *act, *act_prev = NULL;
824
825         ret = nla_parse_nested(tb, TCA_ACT_MAX_PRIO, nla, NULL);
826         if (ret < 0)
827                 return ret;
828
829         if (event == RTM_DELACTION && n->nlmsg_flags&NLM_F_ROOT) {
830                 if (tb[1] != NULL)
831                         return tca_action_flush(tb[1], n, pid);
832                 else
833                         return -EINVAL;
834         }
835
836         for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
837                 act = tcf_action_get_1(tb[i], n, pid);
838                 if (IS_ERR(act)) {
839                         ret = PTR_ERR(act);
840                         goto err;
841                 }
842                 act->order = i;
843
844                 if (head == NULL)
845                         head = act;
846                 else
847                         act_prev->next = act;
848                 act_prev = act;
849         }
850
851         if (event == RTM_GETACTION)
852                 ret = act_get_notify(pid, n, head, event);
853         else { /* delete */
854                 struct sk_buff *skb;
855
856                 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
857                 if (!skb) {
858                         ret = -ENOBUFS;
859                         goto err;
860                 }
861
862                 if (tca_get_fill(skb, head, pid, n->nlmsg_seq, 0, event,
863                                  0, 1) <= 0) {
864                         kfree_skb(skb);
865                         ret = -EINVAL;
866                         goto err;
867                 }
868
869                 /* now do the delete */
870                 tcf_action_destroy(head, 0);
871                 ret = rtnetlink_send(skb, &init_net, pid, RTNLGRP_TC,
872                                      n->nlmsg_flags&NLM_F_ECHO);
873                 if (ret > 0)
874                         return 0;
875                 return ret;
876         }
877 err:
878         cleanup_a(head);
879         return ret;
880 }
881
882 static int tcf_add_notify(struct tc_action *a, u32 pid, u32 seq, int event,
883                           u16 flags)
884 {
885         struct tcamsg *t;
886         struct nlmsghdr *nlh;
887         struct sk_buff *skb;
888         struct nlattr *nest;
889         unsigned char *b;
890         int err = 0;
891
892         skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
893         if (!skb)
894                 return -ENOBUFS;
895
896         b = skb_tail_pointer(skb);
897
898         nlh = NLMSG_NEW(skb, pid, seq, event, sizeof(*t), flags);
899         t = NLMSG_DATA(nlh);
900         t->tca_family = AF_UNSPEC;
901         t->tca__pad1 = 0;
902         t->tca__pad2 = 0;
903
904         nest = nla_nest_start(skb, TCA_ACT_TAB);
905         if (nest == NULL)
906                 goto nla_put_failure;
907
908         if (tcf_action_dump(skb, a, 0, 0) < 0)
909                 goto nla_put_failure;
910
911         nla_nest_end(skb, nest);
912
913         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
914         NETLINK_CB(skb).dst_group = RTNLGRP_TC;
915
916         err = rtnetlink_send(skb, &init_net, pid, RTNLGRP_TC, flags&NLM_F_ECHO);
917         if (err > 0)
918                 err = 0;
919         return err;
920
921 nla_put_failure:
922 nlmsg_failure:
923         kfree_skb(skb);
924         return -1;
925 }
926
927
928 static int
929 tcf_action_add(struct nlattr *nla, struct nlmsghdr *n, u32 pid, int ovr)
930 {
931         int ret = 0;
932         struct tc_action *act;
933         struct tc_action *a;
934         u32 seq = n->nlmsg_seq;
935
936         act = tcf_action_init(nla, NULL, NULL, ovr, 0);
937         if (act == NULL)
938                 goto done;
939         if (IS_ERR(act)) {
940                 ret = PTR_ERR(act);
941                 goto done;
942         }
943
944         /* dump then free all the actions after update; inserted policy
945          * stays intact
946          * */
947         ret = tcf_add_notify(act, pid, seq, RTM_NEWACTION, n->nlmsg_flags);
948         for (a = act; a; a = act) {
949                 act = a->next;
950                 kfree(a);
951         }
952 done:
953         return ret;
954 }
955
956 static int tc_ctl_action(struct sk_buff *skb, struct nlmsghdr *n, void *arg)
957 {
958         struct net *net = sock_net(skb->sk);
959         struct nlattr *tca[TCA_ACT_MAX + 1];
960         u32 pid = skb ? NETLINK_CB(skb).pid : 0;
961         int ret = 0, ovr = 0;
962
963         if (net != &init_net)
964                 return -EINVAL;
965
966         ret = nlmsg_parse(n, sizeof(struct tcamsg), tca, TCA_ACT_MAX, NULL);
967         if (ret < 0)
968                 return ret;
969
970         if (tca[TCA_ACT_TAB] == NULL) {
971                 printk("tc_ctl_action: received NO action attribs\n");
972                 return -EINVAL;
973         }
974
975         /* n->nlmsg_flags&NLM_F_CREATE
976          * */
977         switch (n->nlmsg_type) {
978         case RTM_NEWACTION:
979                 /* we are going to assume all other flags
980                  * imply create only if it doesnt exist
981                  * Note that CREATE | EXCL implies that
982                  * but since we want avoid ambiguity (eg when flags
983                  * is zero) then just set this
984                  */
985                 if (n->nlmsg_flags&NLM_F_REPLACE)
986                         ovr = 1;
987 replay:
988                 ret = tcf_action_add(tca[TCA_ACT_TAB], n, pid, ovr);
989                 if (ret == -EAGAIN)
990                         goto replay;
991                 break;
992         case RTM_DELACTION:
993                 ret = tca_action_gd(tca[TCA_ACT_TAB], n, pid, RTM_DELACTION);
994                 break;
995         case RTM_GETACTION:
996                 ret = tca_action_gd(tca[TCA_ACT_TAB], n, pid, RTM_GETACTION);
997                 break;
998         default:
999                 BUG();
1000         }
1001
1002         return ret;
1003 }
1004
1005 static struct nlattr *
1006 find_dump_kind(struct nlmsghdr *n)
1007 {
1008         struct nlattr *tb1, *tb2[TCA_ACT_MAX+1];
1009         struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
1010         struct nlattr *nla[TCAA_MAX + 1];
1011         struct nlattr *kind;
1012
1013         if (nlmsg_parse(n, sizeof(struct tcamsg), nla, TCAA_MAX, NULL) < 0)
1014                 return NULL;
1015         tb1 = nla[TCA_ACT_TAB];
1016         if (tb1 == NULL)
1017                 return NULL;
1018
1019         if (nla_parse(tb, TCA_ACT_MAX_PRIO, nla_data(tb1),
1020                       NLMSG_ALIGN(nla_len(tb1)), NULL) < 0)
1021                 return NULL;
1022
1023         if (tb[1] == NULL)
1024                 return NULL;
1025         if (nla_parse(tb2, TCA_ACT_MAX, nla_data(tb[1]),
1026                       nla_len(tb[1]), NULL) < 0)
1027                 return NULL;
1028         kind = tb2[TCA_ACT_KIND];
1029
1030         return kind;
1031 }
1032
1033 static int
1034 tc_dump_action(struct sk_buff *skb, struct netlink_callback *cb)
1035 {
1036         struct net *net = sock_net(skb->sk);
1037         struct nlmsghdr *nlh;
1038         unsigned char *b = skb_tail_pointer(skb);
1039         struct nlattr *nest;
1040         struct tc_action_ops *a_o;
1041         struct tc_action a;
1042         int ret = 0;
1043         struct tcamsg *t = (struct tcamsg *) NLMSG_DATA(cb->nlh);
1044         struct nlattr *kind = find_dump_kind(cb->nlh);
1045
1046         if (net != &init_net)
1047                 return 0;
1048
1049         if (kind == NULL) {
1050                 printk("tc_dump_action: action bad kind\n");
1051                 return 0;
1052         }
1053
1054         a_o = tc_lookup_action(kind);
1055         if (a_o == NULL) {
1056                 return 0;
1057         }
1058
1059         memset(&a, 0, sizeof(struct tc_action));
1060         a.ops = a_o;
1061
1062         if (a_o->walk == NULL) {
1063                 printk("tc_dump_action: %s !capable of dumping table\n", a_o->kind);
1064                 goto nla_put_failure;
1065         }
1066
1067         nlh = NLMSG_PUT(skb, NETLINK_CB(cb->skb).pid, cb->nlh->nlmsg_seq,
1068                         cb->nlh->nlmsg_type, sizeof(*t));
1069         t = NLMSG_DATA(nlh);
1070         t->tca_family = AF_UNSPEC;
1071         t->tca__pad1 = 0;
1072         t->tca__pad2 = 0;
1073
1074         nest = nla_nest_start(skb, TCA_ACT_TAB);
1075         if (nest == NULL)
1076                 goto nla_put_failure;
1077
1078         ret = a_o->walk(skb, cb, RTM_GETACTION, &a);
1079         if (ret < 0)
1080                 goto nla_put_failure;
1081
1082         if (ret > 0) {
1083                 nla_nest_end(skb, nest);
1084                 ret = skb->len;
1085         } else
1086                 nla_nest_cancel(skb, nest);
1087
1088         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1089         if (NETLINK_CB(cb->skb).pid && ret)
1090                 nlh->nlmsg_flags |= NLM_F_MULTI;
1091         module_put(a_o->owner);
1092         return skb->len;
1093
1094 nla_put_failure:
1095 nlmsg_failure:
1096         module_put(a_o->owner);
1097         nlmsg_trim(skb, b);
1098         return skb->len;
1099 }
1100
1101 static int __init tc_action_init(void)
1102 {
1103         rtnl_register(PF_UNSPEC, RTM_NEWACTION, tc_ctl_action, NULL);
1104         rtnl_register(PF_UNSPEC, RTM_DELACTION, tc_ctl_action, NULL);
1105         rtnl_register(PF_UNSPEC, RTM_GETACTION, tc_ctl_action, tc_dump_action);
1106
1107         return 0;
1108 }
1109
1110 subsys_initcall(tc_action_init);