act_api.c revision b854272b3c732316676e9128f7b9e6f1e1ff88b0 
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 <net/net_namespace.h>
22#include <net/sock.h>
23#include <net/sch_generic.h>
24#include <net/act_api.h>
25#include <net/netlink.h>
26
27void tcf_hash_destroy(struct tcf_common *p, struct tcf_hashinfo *hinfo)
28{
29	unsigned int h = tcf_hash(p->tcfc_index, hinfo->hmask);
30	struct tcf_common **p1p;
31
32	for (p1p = &hinfo->htab[h]; *p1p; p1p = &(*p1p)->tcfc_next) {
33		if (*p1p == p) {
34			write_lock_bh(hinfo->lock);
35			*p1p = p->tcfc_next;
36			write_unlock_bh(hinfo->lock);
37			gen_kill_estimator(&p->tcfc_bstats,
38					   &p->tcfc_rate_est);
39			kfree(p);
40			return;
41		}
42	}
43	BUG_TRAP(0);
44}
45EXPORT_SYMBOL(tcf_hash_destroy);
46
47int tcf_hash_release(struct tcf_common *p, int bind,
48		     struct tcf_hashinfo *hinfo)
49{
50	int ret = 0;
51
52	if (p) {
53		if (bind)
54			p->tcfc_bindcnt--;
55
56		p->tcfc_refcnt--;
57		if (p->tcfc_bindcnt <= 0 && p->tcfc_refcnt <= 0) {
58			tcf_hash_destroy(p, hinfo);
59			ret = 1;
60		}
61	}
62	return ret;
63}
64EXPORT_SYMBOL(tcf_hash_release);
65
66static int tcf_dump_walker(struct sk_buff *skb, struct netlink_callback *cb,
67			   struct tc_action *a, struct tcf_hashinfo *hinfo)
68{
69	struct tcf_common *p;
70	int err = 0, index = -1,i = 0, s_i = 0, n_i = 0;
71	struct rtattr *r ;
72
73	read_lock_bh(hinfo->lock);
74
75	s_i = cb->args[0];
76
77	for (i = 0; i < (hinfo->hmask + 1); i++) {
78		p = hinfo->htab[tcf_hash(i, hinfo->hmask)];
79
80		for (; p; p = p->tcfc_next) {
81			index++;
82			if (index < s_i)
83				continue;
84			a->priv = p;
85			a->order = n_i;
86			r = (struct rtattr *)skb_tail_pointer(skb);
87			RTA_PUT(skb, a->order, 0, NULL);
88			err = tcf_action_dump_1(skb, a, 0, 0);
89			if (err < 0) {
90				index--;
91				nlmsg_trim(skb, r);
92				goto done;
93			}
94			r->rta_len = skb_tail_pointer(skb) - (u8 *)r;
95			n_i++;
96			if (n_i >= TCA_ACT_MAX_PRIO)
97				goto done;
98		}
99	}
100done:
101	read_unlock_bh(hinfo->lock);
102	if (n_i)
103		cb->args[0] += n_i;
104	return n_i;
105
106rtattr_failure:
107	nlmsg_trim(skb, r);
108	goto done;
109}
110
111static int tcf_del_walker(struct sk_buff *skb, struct tc_action *a,
112			  struct tcf_hashinfo *hinfo)
113{
114	struct tcf_common *p, *s_p;
115	struct rtattr *r ;
116	int i= 0, n_i = 0;
117
118	r = (struct rtattr *)skb_tail_pointer(skb);
119	RTA_PUT(skb, a->order, 0, NULL);
120	RTA_PUT(skb, TCA_KIND, IFNAMSIZ, a->ops->kind);
121	for (i = 0; i < (hinfo->hmask + 1); i++) {
122		p = hinfo->htab[tcf_hash(i, hinfo->hmask)];
123
124		while (p != NULL) {
125			s_p = p->tcfc_next;
126			if (ACT_P_DELETED == tcf_hash_release(p, 0, hinfo))
127				 module_put(a->ops->owner);
128			n_i++;
129			p = s_p;
130		}
131	}
132	RTA_PUT(skb, TCA_FCNT, 4, &n_i);
133	r->rta_len = skb_tail_pointer(skb) - (u8 *)r;
134
135	return n_i;
136rtattr_failure:
137	nlmsg_trim(skb, r);
138	return -EINVAL;
139}
140
141int tcf_generic_walker(struct sk_buff *skb, struct netlink_callback *cb,
142		       int type, struct tc_action *a)
143{
144	struct tcf_hashinfo *hinfo = a->ops->hinfo;
145
146	if (type == RTM_DELACTION) {
147		return tcf_del_walker(skb, a, hinfo);
148	} else if (type == RTM_GETACTION) {
149		return tcf_dump_walker(skb, cb, a, hinfo);
150	} else {
151		printk("tcf_generic_walker: unknown action %d\n", type);
152		return -EINVAL;
153	}
154}
155EXPORT_SYMBOL(tcf_generic_walker);
156
157struct tcf_common *tcf_hash_lookup(u32 index, struct tcf_hashinfo *hinfo)
158{
159	struct tcf_common *p;
160
161	read_lock_bh(hinfo->lock);
162	for (p = hinfo->htab[tcf_hash(index, hinfo->hmask)]; p;
163	     p = p->tcfc_next) {
164		if (p->tcfc_index == index)
165			break;
166	}
167	read_unlock_bh(hinfo->lock);
168
169	return p;
170}
171EXPORT_SYMBOL(tcf_hash_lookup);
172
173u32 tcf_hash_new_index(u32 *idx_gen, struct tcf_hashinfo *hinfo)
174{
175	u32 val = *idx_gen;
176
177	do {
178		if (++val == 0)
179			val = 1;
180	} while (tcf_hash_lookup(val, hinfo));
181
182	return (*idx_gen = val);
183}
184EXPORT_SYMBOL(tcf_hash_new_index);
185
186int tcf_hash_search(struct tc_action *a, u32 index)
187{
188	struct tcf_hashinfo *hinfo = a->ops->hinfo;
189	struct tcf_common *p = tcf_hash_lookup(index, hinfo);
190
191	if (p) {
192		a->priv = p;
193		return 1;
194	}
195	return 0;
196}
197EXPORT_SYMBOL(tcf_hash_search);
198
199struct tcf_common *tcf_hash_check(u32 index, struct tc_action *a, int bind,
200				  struct tcf_hashinfo *hinfo)
201{
202	struct tcf_common *p = NULL;
203	if (index && (p = tcf_hash_lookup(index, hinfo)) != NULL) {
204		if (bind) {
205			p->tcfc_bindcnt++;
206			p->tcfc_refcnt++;
207		}
208		a->priv = p;
209	}
210	return p;
211}
212EXPORT_SYMBOL(tcf_hash_check);
213
214struct tcf_common *tcf_hash_create(u32 index, struct rtattr *est, struct tc_action *a, int size, int bind, u32 *idx_gen, struct tcf_hashinfo *hinfo)
215{
216	struct tcf_common *p = kzalloc(size, GFP_KERNEL);
217
218	if (unlikely(!p))
219		return p;
220	p->tcfc_refcnt = 1;
221	if (bind)
222		p->tcfc_bindcnt = 1;
223
224	spin_lock_init(&p->tcfc_lock);
225	p->tcfc_index = index ? index : tcf_hash_new_index(idx_gen, hinfo);
226	p->tcfc_tm.install = jiffies;
227	p->tcfc_tm.lastuse = jiffies;
228	if (est)
229		gen_new_estimator(&p->tcfc_bstats, &p->tcfc_rate_est,
230				  &p->tcfc_lock, est);
231	a->priv = (void *) p;
232	return p;
233}
234EXPORT_SYMBOL(tcf_hash_create);
235
236void tcf_hash_insert(struct tcf_common *p, struct tcf_hashinfo *hinfo)
237{
238	unsigned int h = tcf_hash(p->tcfc_index, hinfo->hmask);
239
240	write_lock_bh(hinfo->lock);
241	p->tcfc_next = hinfo->htab[h];
242	hinfo->htab[h] = p;
243	write_unlock_bh(hinfo->lock);
244}
245EXPORT_SYMBOL(tcf_hash_insert);
246
247static struct tc_action_ops *act_base = NULL;
248static DEFINE_RWLOCK(act_mod_lock);
249
250int tcf_register_action(struct tc_action_ops *act)
251{
252	struct tc_action_ops *a, **ap;
253
254	write_lock(&act_mod_lock);
255	for (ap = &act_base; (a = *ap) != NULL; ap = &a->next) {
256		if (act->type == a->type || (strcmp(act->kind, a->kind) == 0)) {
257			write_unlock(&act_mod_lock);
258			return -EEXIST;
259		}
260	}
261	act->next = NULL;
262	*ap = act;
263	write_unlock(&act_mod_lock);
264	return 0;
265}
266
267int tcf_unregister_action(struct tc_action_ops *act)
268{
269	struct tc_action_ops *a, **ap;
270	int err = -ENOENT;
271
272	write_lock(&act_mod_lock);
273	for (ap = &act_base; (a = *ap) != NULL; ap = &a->next)
274		if (a == act)
275			break;
276	if (a) {
277		*ap = a->next;
278		a->next = NULL;
279		err = 0;
280	}
281	write_unlock(&act_mod_lock);
282	return err;
283}
284
285/* lookup by name */
286static struct tc_action_ops *tc_lookup_action_n(char *kind)
287{
288	struct tc_action_ops *a = NULL;
289
290	if (kind) {
291		read_lock(&act_mod_lock);
292		for (a = act_base; a; a = a->next) {
293			if (strcmp(kind, a->kind) == 0) {
294				if (!try_module_get(a->owner)) {
295					read_unlock(&act_mod_lock);
296					return NULL;
297				}
298				break;
299			}
300		}
301		read_unlock(&act_mod_lock);
302	}
303	return a;
304}
305
306/* lookup by rtattr */
307static struct tc_action_ops *tc_lookup_action(struct rtattr *kind)
308{
309	struct tc_action_ops *a = NULL;
310
311	if (kind) {
312		read_lock(&act_mod_lock);
313		for (a = act_base; a; a = a->next) {
314			if (rtattr_strcmp(kind, a->kind) == 0) {
315				if (!try_module_get(a->owner)) {
316					read_unlock(&act_mod_lock);
317					return NULL;
318				}
319				break;
320			}
321		}
322		read_unlock(&act_mod_lock);
323	}
324	return a;
325}
326
327#if 0
328/* lookup by id */
329static struct tc_action_ops *tc_lookup_action_id(u32 type)
330{
331	struct tc_action_ops *a = NULL;
332
333	if (type) {
334		read_lock(&act_mod_lock);
335		for (a = act_base; a; a = a->next) {
336			if (a->type == type) {
337				if (!try_module_get(a->owner)) {
338					read_unlock(&act_mod_lock);
339					return NULL;
340				}
341				break;
342			}
343		}
344		read_unlock(&act_mod_lock);
345	}
346	return a;
347}
348#endif
349
350int tcf_action_exec(struct sk_buff *skb, struct tc_action *act,
351		    struct tcf_result *res)
352{
353	struct tc_action *a;
354	int ret = -1;
355
356	if (skb->tc_verd & TC_NCLS) {
357		skb->tc_verd = CLR_TC_NCLS(skb->tc_verd);
358		ret = TC_ACT_OK;
359		goto exec_done;
360	}
361	while ((a = act) != NULL) {
362repeat:
363		if (a->ops && a->ops->act) {
364			ret = a->ops->act(skb, a, res);
365			if (TC_MUNGED & skb->tc_verd) {
366				/* copied already, allow trampling */
367				skb->tc_verd = SET_TC_OK2MUNGE(skb->tc_verd);
368				skb->tc_verd = CLR_TC_MUNGED(skb->tc_verd);
369			}
370			if (ret == TC_ACT_REPEAT)
371				goto repeat;	/* we need a ttl - JHS */
372			if (ret != TC_ACT_PIPE)
373				goto exec_done;
374		}
375		act = a->next;
376	}
377exec_done:
378	return ret;
379}
380
381void tcf_action_destroy(struct tc_action *act, int bind)
382{
383	struct tc_action *a;
384
385	for (a = act; a; a = act) {
386		if (a->ops && a->ops->cleanup) {
387			if (a->ops->cleanup(a, bind) == ACT_P_DELETED)
388				module_put(a->ops->owner);
389			act = act->next;
390			kfree(a);
391		} else { /*FIXME: Remove later - catch insertion bugs*/
392			printk("tcf_action_destroy: BUG? destroying NULL ops\n");
393			act = act->next;
394			kfree(a);
395		}
396	}
397}
398
399int
400tcf_action_dump_old(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
401{
402	int err = -EINVAL;
403
404	if (a->ops == NULL || a->ops->dump == NULL)
405		return err;
406	return a->ops->dump(skb, a, bind, ref);
407}
408
409int
410tcf_action_dump_1(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
411{
412	int err = -EINVAL;
413	unsigned char *b = skb_tail_pointer(skb);
414	struct rtattr *r;
415
416	if (a->ops == NULL || a->ops->dump == NULL)
417		return err;
418
419	RTA_PUT(skb, TCA_KIND, IFNAMSIZ, a->ops->kind);
420	if (tcf_action_copy_stats(skb, a, 0))
421		goto rtattr_failure;
422	r = (struct rtattr *)skb_tail_pointer(skb);
423	RTA_PUT(skb, TCA_OPTIONS, 0, NULL);
424	if ((err = tcf_action_dump_old(skb, a, bind, ref)) > 0) {
425		r->rta_len = skb_tail_pointer(skb) - (u8 *)r;
426		return err;
427	}
428
429rtattr_failure:
430	nlmsg_trim(skb, b);
431	return -1;
432}
433
434int
435tcf_action_dump(struct sk_buff *skb, struct tc_action *act, int bind, int ref)
436{
437	struct tc_action *a;
438	int err = -EINVAL;
439	unsigned char *b = skb_tail_pointer(skb);
440	struct rtattr *r ;
441
442	while ((a = act) != NULL) {
443		r = (struct rtattr *)skb_tail_pointer(skb);
444		act = a->next;
445		RTA_PUT(skb, a->order, 0, NULL);
446		err = tcf_action_dump_1(skb, a, bind, ref);
447		if (err < 0)
448			goto errout;
449		r->rta_len = skb_tail_pointer(skb) - (u8 *)r;
450	}
451
452	return 0;
453
454rtattr_failure:
455	err = -EINVAL;
456errout:
457	nlmsg_trim(skb, b);
458	return err;
459}
460
461struct tc_action *tcf_action_init_1(struct rtattr *rta, struct rtattr *est,
462				    char *name, int ovr, int bind, int *err)
463{
464	struct tc_action *a;
465	struct tc_action_ops *a_o;
466	char act_name[IFNAMSIZ];
467	struct rtattr *tb[TCA_ACT_MAX+1];
468	struct rtattr *kind;
469
470	*err = -EINVAL;
471
472	if (name == NULL) {
473		if (rtattr_parse_nested(tb, TCA_ACT_MAX, rta) < 0)
474			goto err_out;
475		kind = tb[TCA_ACT_KIND-1];
476		if (kind == NULL)
477			goto err_out;
478		if (rtattr_strlcpy(act_name, kind, IFNAMSIZ) >= IFNAMSIZ)
479			goto err_out;
480	} else {
481		if (strlcpy(act_name, name, IFNAMSIZ) >= IFNAMSIZ)
482			goto err_out;
483	}
484
485	a_o = tc_lookup_action_n(act_name);
486	if (a_o == NULL) {
487#ifdef CONFIG_KMOD
488		rtnl_unlock();
489		request_module("act_%s", act_name);
490		rtnl_lock();
491
492		a_o = tc_lookup_action_n(act_name);
493
494		/* We dropped the RTNL semaphore in order to
495		 * perform the module load.  So, even if we
496		 * succeeded in loading the module we have to
497		 * tell the caller to replay the request.  We
498		 * indicate this using -EAGAIN.
499		 */
500		if (a_o != NULL) {
501			*err = -EAGAIN;
502			goto err_mod;
503		}
504#endif
505		*err = -ENOENT;
506		goto err_out;
507	}
508
509	*err = -ENOMEM;
510	a = kzalloc(sizeof(*a), GFP_KERNEL);
511	if (a == NULL)
512		goto err_mod;
513
514	/* backward compatibility for policer */
515	if (name == NULL)
516		*err = a_o->init(tb[TCA_ACT_OPTIONS-1], est, a, ovr, bind);
517	else
518		*err = a_o->init(rta, est, a, ovr, bind);
519	if (*err < 0)
520		goto err_free;
521
522	/* module count goes up only when brand new policy is created
523	   if it exists and is only bound to in a_o->init() then
524	   ACT_P_CREATED is not returned (a zero is).
525	*/
526	if (*err != ACT_P_CREATED)
527		module_put(a_o->owner);
528	a->ops = a_o;
529
530	*err = 0;
531	return a;
532
533err_free:
534	kfree(a);
535err_mod:
536	module_put(a_o->owner);
537err_out:
538	return NULL;
539}
540
541struct tc_action *tcf_action_init(struct rtattr *rta, struct rtattr *est,
542				  char *name, int ovr, int bind, int *err)
543{
544	struct rtattr *tb[TCA_ACT_MAX_PRIO+1];
545	struct tc_action *head = NULL, *act, *act_prev = NULL;
546	int i;
547
548	if (rtattr_parse_nested(tb, TCA_ACT_MAX_PRIO, rta) < 0) {
549		*err = -EINVAL;
550		return head;
551	}
552
553	for (i=0; i < TCA_ACT_MAX_PRIO && tb[i]; i++) {
554		act = tcf_action_init_1(tb[i], est, name, ovr, bind, err);
555		if (act == NULL)
556			goto err;
557		act->order = i+1;
558
559		if (head == NULL)
560			head = act;
561		else
562			act_prev->next = act;
563		act_prev = act;
564	}
565	return head;
566
567err:
568	if (head != NULL)
569		tcf_action_destroy(head, bind);
570	return NULL;
571}
572
573int tcf_action_copy_stats(struct sk_buff *skb, struct tc_action *a,
574			  int compat_mode)
575{
576	int err = 0;
577	struct gnet_dump d;
578	struct tcf_act_hdr *h = a->priv;
579
580	if (h == NULL)
581		goto errout;
582
583	/* compat_mode being true specifies a call that is supposed
584	 * to add additional backward compatiblity statistic TLVs.
585	 */
586	if (compat_mode) {
587		if (a->type == TCA_OLD_COMPAT)
588			err = gnet_stats_start_copy_compat(skb, 0,
589				TCA_STATS, TCA_XSTATS, &h->tcf_lock, &d);
590		else
591			return 0;
592	} else
593		err = gnet_stats_start_copy(skb, TCA_ACT_STATS,
594					    &h->tcf_lock, &d);
595
596	if (err < 0)
597		goto errout;
598
599	if (a->ops != NULL && a->ops->get_stats != NULL)
600		if (a->ops->get_stats(skb, a) < 0)
601			goto errout;
602
603	if (gnet_stats_copy_basic(&d, &h->tcf_bstats) < 0 ||
604	    gnet_stats_copy_rate_est(&d, &h->tcf_rate_est) < 0 ||
605	    gnet_stats_copy_queue(&d, &h->tcf_qstats) < 0)
606		goto errout;
607
608	if (gnet_stats_finish_copy(&d) < 0)
609		goto errout;
610
611	return 0;
612
613errout:
614	return -1;
615}
616
617static int
618tca_get_fill(struct sk_buff *skb, struct tc_action *a, u32 pid, u32 seq,
619	     u16 flags, int event, int bind, int ref)
620{
621	struct tcamsg *t;
622	struct nlmsghdr *nlh;
623	unsigned char *b = skb_tail_pointer(skb);
624	struct rtattr *x;
625
626	nlh = NLMSG_NEW(skb, pid, seq, event, sizeof(*t), flags);
627
628	t = NLMSG_DATA(nlh);
629	t->tca_family = AF_UNSPEC;
630	t->tca__pad1 = 0;
631	t->tca__pad2 = 0;
632
633	x = (struct rtattr *)skb_tail_pointer(skb);
634	RTA_PUT(skb, TCA_ACT_TAB, 0, NULL);
635
636	if (tcf_action_dump(skb, a, bind, ref) < 0)
637		goto rtattr_failure;
638
639	x->rta_len = skb_tail_pointer(skb) - (u8 *)x;
640
641	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
642	return skb->len;
643
644rtattr_failure:
645nlmsg_failure:
646	nlmsg_trim(skb, b);
647	return -1;
648}
649
650static int
651act_get_notify(u32 pid, struct nlmsghdr *n, struct tc_action *a, int event)
652{
653	struct sk_buff *skb;
654
655	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
656	if (!skb)
657		return -ENOBUFS;
658	if (tca_get_fill(skb, a, pid, n->nlmsg_seq, 0, event, 0, 0) <= 0) {
659		kfree_skb(skb);
660		return -EINVAL;
661	}
662
663	return rtnl_unicast(skb, pid);
664}
665
666static struct tc_action *
667tcf_action_get_1(struct rtattr *rta, struct nlmsghdr *n, u32 pid, int *err)
668{
669	struct rtattr *tb[TCA_ACT_MAX+1];
670	struct tc_action *a;
671	int index;
672
673	*err = -EINVAL;
674	if (rtattr_parse_nested(tb, TCA_ACT_MAX, rta) < 0)
675		return NULL;
676
677	if (tb[TCA_ACT_INDEX - 1] == NULL ||
678	    RTA_PAYLOAD(tb[TCA_ACT_INDEX - 1]) < sizeof(index))
679		return NULL;
680	index = *(int *)RTA_DATA(tb[TCA_ACT_INDEX - 1]);
681
682	*err = -ENOMEM;
683	a = kzalloc(sizeof(struct tc_action), GFP_KERNEL);
684	if (a == NULL)
685		return NULL;
686
687	*err = -EINVAL;
688	a->ops = tc_lookup_action(tb[TCA_ACT_KIND - 1]);
689	if (a->ops == NULL)
690		goto err_free;
691	if (a->ops->lookup == NULL)
692		goto err_mod;
693	*err = -ENOENT;
694	if (a->ops->lookup(a, index) == 0)
695		goto err_mod;
696
697	module_put(a->ops->owner);
698	*err = 0;
699	return a;
700err_mod:
701	module_put(a->ops->owner);
702err_free:
703	kfree(a);
704	return NULL;
705}
706
707static void cleanup_a(struct tc_action *act)
708{
709	struct tc_action *a;
710
711	for (a = act; a; a = act) {
712		act = a->next;
713		kfree(a);
714	}
715}
716
717static struct tc_action *create_a(int i)
718{
719	struct tc_action *act;
720
721	act = kzalloc(sizeof(*act), GFP_KERNEL);
722	if (act == NULL) {
723		printk("create_a: failed to alloc!\n");
724		return NULL;
725	}
726	act->order = i;
727	return act;
728}
729
730static int tca_action_flush(struct rtattr *rta, struct nlmsghdr *n, u32 pid)
731{
732	struct sk_buff *skb;
733	unsigned char *b;
734	struct nlmsghdr *nlh;
735	struct tcamsg *t;
736	struct netlink_callback dcb;
737	struct rtattr *x;
738	struct rtattr *tb[TCA_ACT_MAX+1];
739	struct rtattr *kind;
740	struct tc_action *a = create_a(0);
741	int err = -EINVAL;
742
743	if (a == NULL) {
744		printk("tca_action_flush: couldnt create tc_action\n");
745		return err;
746	}
747
748	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
749	if (!skb) {
750		printk("tca_action_flush: failed skb alloc\n");
751		kfree(a);
752		return -ENOBUFS;
753	}
754
755	b = skb_tail_pointer(skb);
756
757	if (rtattr_parse_nested(tb, TCA_ACT_MAX, rta) < 0)
758		goto err_out;
759
760	kind = tb[TCA_ACT_KIND-1];
761	a->ops = tc_lookup_action(kind);
762	if (a->ops == NULL)
763		goto err_out;
764
765	nlh = NLMSG_PUT(skb, pid, n->nlmsg_seq, RTM_DELACTION, sizeof(*t));
766	t = NLMSG_DATA(nlh);
767	t->tca_family = AF_UNSPEC;
768	t->tca__pad1 = 0;
769	t->tca__pad2 = 0;
770
771	x = (struct rtattr *)skb_tail_pointer(skb);
772	RTA_PUT(skb, TCA_ACT_TAB, 0, NULL);
773
774	err = a->ops->walk(skb, &dcb, RTM_DELACTION, a);
775	if (err < 0)
776		goto rtattr_failure;
777
778	x->rta_len = skb_tail_pointer(skb) - (u8 *)x;
779
780	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
781	nlh->nlmsg_flags |= NLM_F_ROOT;
782	module_put(a->ops->owner);
783	kfree(a);
784	err = rtnetlink_send(skb, pid, RTNLGRP_TC, n->nlmsg_flags&NLM_F_ECHO);
785	if (err > 0)
786		return 0;
787
788	return err;
789
790rtattr_failure:
791nlmsg_failure:
792	module_put(a->ops->owner);
793err_out:
794	kfree_skb(skb);
795	kfree(a);
796	return err;
797}
798
799static int
800tca_action_gd(struct rtattr *rta, struct nlmsghdr *n, u32 pid, int event)
801{
802	int i, ret = 0;
803	struct rtattr *tb[TCA_ACT_MAX_PRIO+1];
804	struct tc_action *head = NULL, *act, *act_prev = NULL;
805
806	if (rtattr_parse_nested(tb, TCA_ACT_MAX_PRIO, rta) < 0)
807		return -EINVAL;
808
809	if (event == RTM_DELACTION && n->nlmsg_flags&NLM_F_ROOT) {
810		if (tb[0] != NULL && tb[1] == NULL)
811			return tca_action_flush(tb[0], n, pid);
812	}
813
814	for (i=0; i < TCA_ACT_MAX_PRIO && tb[i]; i++) {
815		act = tcf_action_get_1(tb[i], n, pid, &ret);
816		if (act == NULL)
817			goto err;
818		act->order = i+1;
819
820		if (head == NULL)
821			head = act;
822		else
823			act_prev->next = act;
824		act_prev = act;
825	}
826
827	if (event == RTM_GETACTION)
828		ret = act_get_notify(pid, n, head, event);
829	else { /* delete */
830		struct sk_buff *skb;
831
832		skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
833		if (!skb) {
834			ret = -ENOBUFS;
835			goto err;
836		}
837
838		if (tca_get_fill(skb, head, pid, n->nlmsg_seq, 0, event,
839				 0, 1) <= 0) {
840			kfree_skb(skb);
841			ret = -EINVAL;
842			goto err;
843		}
844
845		/* now do the delete */
846		tcf_action_destroy(head, 0);
847		ret = rtnetlink_send(skb, pid, RTNLGRP_TC,
848				     n->nlmsg_flags&NLM_F_ECHO);
849		if (ret > 0)
850			return 0;
851		return ret;
852	}
853err:
854	cleanup_a(head);
855	return ret;
856}
857
858static int tcf_add_notify(struct tc_action *a, u32 pid, u32 seq, int event,
859			  u16 flags)
860{
861	struct tcamsg *t;
862	struct nlmsghdr *nlh;
863	struct sk_buff *skb;
864	struct rtattr *x;
865	unsigned char *b;
866	int err = 0;
867
868	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
869	if (!skb)
870		return -ENOBUFS;
871
872	b = skb_tail_pointer(skb);
873
874	nlh = NLMSG_NEW(skb, pid, seq, event, sizeof(*t), flags);
875	t = NLMSG_DATA(nlh);
876	t->tca_family = AF_UNSPEC;
877	t->tca__pad1 = 0;
878	t->tca__pad2 = 0;
879
880	x = (struct rtattr *)skb_tail_pointer(skb);
881	RTA_PUT(skb, TCA_ACT_TAB, 0, NULL);
882
883	if (tcf_action_dump(skb, a, 0, 0) < 0)
884		goto rtattr_failure;
885
886	x->rta_len = skb_tail_pointer(skb) - (u8 *)x;
887
888	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
889	NETLINK_CB(skb).dst_group = RTNLGRP_TC;
890
891	err = rtnetlink_send(skb, pid, RTNLGRP_TC, flags&NLM_F_ECHO);
892	if (err > 0)
893		err = 0;
894	return err;
895
896rtattr_failure:
897nlmsg_failure:
898	kfree_skb(skb);
899	return -1;
900}
901
902
903static int
904tcf_action_add(struct rtattr *rta, struct nlmsghdr *n, u32 pid, int ovr)
905{
906	int ret = 0;
907	struct tc_action *act;
908	struct tc_action *a;
909	u32 seq = n->nlmsg_seq;
910
911	act = tcf_action_init(rta, NULL, NULL, ovr, 0, &ret);
912	if (act == NULL)
913		goto done;
914
915	/* dump then free all the actions after update; inserted policy
916	 * stays intact
917	 * */
918	ret = tcf_add_notify(act, pid, seq, RTM_NEWACTION, n->nlmsg_flags);
919	for (a = act; a; a = act) {
920		act = a->next;
921		kfree(a);
922	}
923done:
924	return ret;
925}
926
927static int tc_ctl_action(struct sk_buff *skb, struct nlmsghdr *n, void *arg)
928{
929	struct net *net = skb->sk->sk_net;
930	struct rtattr **tca = arg;
931	u32 pid = skb ? NETLINK_CB(skb).pid : 0;
932	int ret = 0, ovr = 0;
933
934	if (net != &init_net)
935		return -EINVAL;
936
937	if (tca[TCA_ACT_TAB-1] == NULL) {
938		printk("tc_ctl_action: received NO action attribs\n");
939		return -EINVAL;
940	}
941
942	/* n->nlmsg_flags&NLM_F_CREATE
943	 * */
944	switch (n->nlmsg_type) {
945	case RTM_NEWACTION:
946		/* we are going to assume all other flags
947		 * imply create only if it doesnt exist
948		 * Note that CREATE | EXCL implies that
949		 * but since we want avoid ambiguity (eg when flags
950		 * is zero) then just set this
951		 */
952		if (n->nlmsg_flags&NLM_F_REPLACE)
953			ovr = 1;
954replay:
955		ret = tcf_action_add(tca[TCA_ACT_TAB-1], n, pid, ovr);
956		if (ret == -EAGAIN)
957			goto replay;
958		break;
959	case RTM_DELACTION:
960		ret = tca_action_gd(tca[TCA_ACT_TAB-1], n, pid, RTM_DELACTION);
961		break;
962	case RTM_GETACTION:
963		ret = tca_action_gd(tca[TCA_ACT_TAB-1], n, pid, RTM_GETACTION);
964		break;
965	default:
966		BUG();
967	}
968
969	return ret;
970}
971
972static struct rtattr *
973find_dump_kind(struct nlmsghdr *n)
974{
975	struct rtattr *tb1, *tb2[TCA_ACT_MAX+1];
976	struct rtattr *tb[TCA_ACT_MAX_PRIO + 1];
977	struct rtattr *rta[TCAA_MAX + 1];
978	struct rtattr *kind;
979	int min_len = NLMSG_LENGTH(sizeof(struct tcamsg));
980	int attrlen = n->nlmsg_len - NLMSG_ALIGN(min_len);
981	struct rtattr *attr = (void *) n + NLMSG_ALIGN(min_len);
982
983	if (rtattr_parse(rta, TCAA_MAX, attr, attrlen) < 0)
984		return NULL;
985	tb1 = rta[TCA_ACT_TAB - 1];
986	if (tb1 == NULL)
987		return NULL;
988
989	if (rtattr_parse(tb, TCA_ACT_MAX_PRIO, RTA_DATA(tb1),
990			 NLMSG_ALIGN(RTA_PAYLOAD(tb1))) < 0)
991		return NULL;
992	if (tb[0] == NULL)
993		return NULL;
994
995	if (rtattr_parse(tb2, TCA_ACT_MAX, RTA_DATA(tb[0]),
996			 RTA_PAYLOAD(tb[0])) < 0)
997		return NULL;
998	kind = tb2[TCA_ACT_KIND-1];
999
1000	return kind;
1001}
1002
1003static int
1004tc_dump_action(struct sk_buff *skb, struct netlink_callback *cb)
1005{
1006	struct net *net = skb->sk->sk_net;
1007	struct nlmsghdr *nlh;
1008	unsigned char *b = skb_tail_pointer(skb);
1009	struct rtattr *x;
1010	struct tc_action_ops *a_o;
1011	struct tc_action a;
1012	int ret = 0;
1013	struct tcamsg *t = (struct tcamsg *) NLMSG_DATA(cb->nlh);
1014	struct rtattr *kind = find_dump_kind(cb->nlh);
1015
1016	if (net != &init_net)
1017		return 0;
1018
1019	if (kind == NULL) {
1020		printk("tc_dump_action: action bad kind\n");
1021		return 0;
1022	}
1023
1024	a_o = tc_lookup_action(kind);
1025	if (a_o == NULL) {
1026		return 0;
1027	}
1028
1029	memset(&a, 0, sizeof(struct tc_action));
1030	a.ops = a_o;
1031
1032	if (a_o->walk == NULL) {
1033		printk("tc_dump_action: %s !capable of dumping table\n", a_o->kind);
1034		goto rtattr_failure;
1035	}
1036
1037	nlh = NLMSG_PUT(skb, NETLINK_CB(cb->skb).pid, cb->nlh->nlmsg_seq,
1038			cb->nlh->nlmsg_type, sizeof(*t));
1039	t = NLMSG_DATA(nlh);
1040	t->tca_family = AF_UNSPEC;
1041	t->tca__pad1 = 0;
1042	t->tca__pad2 = 0;
1043
1044	x = (struct rtattr *)skb_tail_pointer(skb);
1045	RTA_PUT(skb, TCA_ACT_TAB, 0, NULL);
1046
1047	ret = a_o->walk(skb, cb, RTM_GETACTION, &a);
1048	if (ret < 0)
1049		goto rtattr_failure;
1050
1051	if (ret > 0) {
1052		x->rta_len = skb_tail_pointer(skb) - (u8 *)x;
1053		ret = skb->len;
1054	} else
1055		nlmsg_trim(skb, x);
1056
1057	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1058	if (NETLINK_CB(cb->skb).pid && ret)
1059		nlh->nlmsg_flags |= NLM_F_MULTI;
1060	module_put(a_o->owner);
1061	return skb->len;
1062
1063rtattr_failure:
1064nlmsg_failure:
1065	module_put(a_o->owner);
1066	nlmsg_trim(skb, b);
1067	return skb->len;
1068}
1069
1070static int __init tc_action_init(void)
1071{
1072	rtnl_register(PF_UNSPEC, RTM_NEWACTION, tc_ctl_action, NULL);
1073	rtnl_register(PF_UNSPEC, RTM_DELACTION, tc_ctl_action, NULL);
1074	rtnl_register(PF_UNSPEC, RTM_GETACTION, tc_ctl_action, tc_dump_action);
1075
1076	return 0;
1077}
1078
1079subsys_initcall(tc_action_init);
1080
1081EXPORT_SYMBOL(tcf_register_action);
1082EXPORT_SYMBOL(tcf_unregister_action);
1083EXPORT_SYMBOL(tcf_action_exec);
1084EXPORT_SYMBOL(tcf_action_dump_1);
1085