1/*
2 * net/sched/cls_u32.c	Ugly (or Universal) 32bit key Packet Classifier.
3 *
4 *		This program is free software; you can redistribute it and/or
5 *		modify it under the terms of the GNU General Public License
6 *		as published by the Free Software Foundation; either version
7 *		2 of the License, or (at your option) any later version.
8 *
9 * Authors:	Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
10 *
11 *	The filters are packed to hash tables of key nodes
12 *	with a set of 32bit key/mask pairs at every node.
13 *	Nodes reference next level hash tables etc.
14 *
15 *	This scheme is the best universal classifier I managed to
16 *	invent; it is not super-fast, but it is not slow (provided you
17 *	program it correctly), and general enough.  And its relative
18 *	speed grows as the number of rules becomes larger.
19 *
20 *	It seems that it represents the best middle point between
21 *	speed and manageability both by human and by machine.
22 *
23 *	It is especially useful for link sharing combined with QoS;
24 *	pure RSVP doesn't need such a general approach and can use
25 *	much simpler (and faster) schemes, sort of cls_rsvp.c.
26 *
27 *	JHS: We should remove the CONFIG_NET_CLS_IND from here
28 *	eventually when the meta match extension is made available
29 *
30 *	nfmark match added by Catalin(ux aka Dino) BOIE <catab at umbrella.ro>
31 */
32
33#include <linux/module.h>
34#include <linux/slab.h>
35#include <linux/types.h>
36#include <linux/kernel.h>
37#include <linux/string.h>
38#include <linux/errno.h>
39#include <linux/percpu.h>
40#include <linux/rtnetlink.h>
41#include <linux/skbuff.h>
42#include <linux/bitmap.h>
43#include <net/netlink.h>
44#include <net/act_api.h>
45#include <net/pkt_cls.h>
46
47struct tc_u_knode {
48	struct tc_u_knode __rcu	*next;
49	u32			handle;
50	struct tc_u_hnode __rcu	*ht_up;
51	struct tcf_exts		exts;
52#ifdef CONFIG_NET_CLS_IND
53	int			ifindex;
54#endif
55	u8			fshift;
56	struct tcf_result	res;
57	struct tc_u_hnode __rcu	*ht_down;
58#ifdef CONFIG_CLS_U32_PERF
59	struct tc_u32_pcnt __percpu *pf;
60#endif
61#ifdef CONFIG_CLS_U32_MARK
62	u32			val;
63	u32			mask;
64	u32 __percpu		*pcpu_success;
65#endif
66	struct tcf_proto	*tp;
67	struct rcu_head		rcu;
68	/* The 'sel' field MUST be the last field in structure to allow for
69	 * tc_u32_keys allocated at end of structure.
70	 */
71	struct tc_u32_sel	sel;
72};
73
74struct tc_u_hnode {
75	struct tc_u_hnode __rcu	*next;
76	u32			handle;
77	u32			prio;
78	struct tc_u_common	*tp_c;
79	int			refcnt;
80	unsigned int		divisor;
81	struct rcu_head		rcu;
82	/* The 'ht' field MUST be the last field in structure to allow for
83	 * more entries allocated at end of structure.
84	 */
85	struct tc_u_knode __rcu	*ht[1];
86};
87
88struct tc_u_common {
89	struct tc_u_hnode __rcu	*hlist;
90	struct Qdisc		*q;
91	int			refcnt;
92	u32			hgenerator;
93	struct rcu_head		rcu;
94};
95
96static inline unsigned int u32_hash_fold(__be32 key,
97					 const struct tc_u32_sel *sel,
98					 u8 fshift)
99{
100	unsigned int h = ntohl(key & sel->hmask) >> fshift;
101
102	return h;
103}
104
105static int u32_classify(struct sk_buff *skb, const struct tcf_proto *tp, struct tcf_result *res)
106{
107	struct {
108		struct tc_u_knode *knode;
109		unsigned int	  off;
110	} stack[TC_U32_MAXDEPTH];
111
112	struct tc_u_hnode *ht = rcu_dereference_bh(tp->root);
113	unsigned int off = skb_network_offset(skb);
114	struct tc_u_knode *n;
115	int sdepth = 0;
116	int off2 = 0;
117	int sel = 0;
118#ifdef CONFIG_CLS_U32_PERF
119	int j;
120#endif
121	int i, r;
122
123next_ht:
124	n = rcu_dereference_bh(ht->ht[sel]);
125
126next_knode:
127	if (n) {
128		struct tc_u32_key *key = n->sel.keys;
129
130#ifdef CONFIG_CLS_U32_PERF
131		__this_cpu_inc(n->pf->rcnt);
132		j = 0;
133#endif
134
135#ifdef CONFIG_CLS_U32_MARK
136		if ((skb->mark & n->mask) != n->val) {
137			n = rcu_dereference_bh(n->next);
138			goto next_knode;
139		} else {
140			__this_cpu_inc(*n->pcpu_success);
141		}
142#endif
143
144		for (i = n->sel.nkeys; i > 0; i--, key++) {
145			int toff = off + key->off + (off2 & key->offmask);
146			__be32 *data, hdata;
147
148			if (skb_headroom(skb) + toff > INT_MAX)
149				goto out;
150
151			data = skb_header_pointer(skb, toff, 4, &hdata);
152			if (!data)
153				goto out;
154			if ((*data ^ key->val) & key->mask) {
155				n = rcu_dereference_bh(n->next);
156				goto next_knode;
157			}
158#ifdef CONFIG_CLS_U32_PERF
159			__this_cpu_inc(n->pf->kcnts[j]);
160			j++;
161#endif
162		}
163
164		ht = rcu_dereference_bh(n->ht_down);
165		if (!ht) {
166check_terminal:
167			if (n->sel.flags & TC_U32_TERMINAL) {
168
169				*res = n->res;
170#ifdef CONFIG_NET_CLS_IND
171				if (!tcf_match_indev(skb, n->ifindex)) {
172					n = rcu_dereference_bh(n->next);
173					goto next_knode;
174				}
175#endif
176#ifdef CONFIG_CLS_U32_PERF
177				__this_cpu_inc(n->pf->rhit);
178#endif
179				r = tcf_exts_exec(skb, &n->exts, res);
180				if (r < 0) {
181					n = rcu_dereference_bh(n->next);
182					goto next_knode;
183				}
184
185				return r;
186			}
187			n = rcu_dereference_bh(n->next);
188			goto next_knode;
189		}
190
191		/* PUSH */
192		if (sdepth >= TC_U32_MAXDEPTH)
193			goto deadloop;
194		stack[sdepth].knode = n;
195		stack[sdepth].off = off;
196		sdepth++;
197
198		ht = rcu_dereference_bh(n->ht_down);
199		sel = 0;
200		if (ht->divisor) {
201			__be32 *data, hdata;
202
203			data = skb_header_pointer(skb, off + n->sel.hoff, 4,
204						  &hdata);
205			if (!data)
206				goto out;
207			sel = ht->divisor & u32_hash_fold(*data, &n->sel,
208							  n->fshift);
209		}
210		if (!(n->sel.flags & (TC_U32_VAROFFSET | TC_U32_OFFSET | TC_U32_EAT)))
211			goto next_ht;
212
213		if (n->sel.flags & (TC_U32_OFFSET | TC_U32_VAROFFSET)) {
214			off2 = n->sel.off + 3;
215			if (n->sel.flags & TC_U32_VAROFFSET) {
216				__be16 *data, hdata;
217
218				data = skb_header_pointer(skb,
219							  off + n->sel.offoff,
220							  2, &hdata);
221				if (!data)
222					goto out;
223				off2 += ntohs(n->sel.offmask & *data) >>
224					n->sel.offshift;
225			}
226			off2 &= ~3;
227		}
228		if (n->sel.flags & TC_U32_EAT) {
229			off += off2;
230			off2 = 0;
231		}
232
233		if (off < skb->len)
234			goto next_ht;
235	}
236
237	/* POP */
238	if (sdepth--) {
239		n = stack[sdepth].knode;
240		ht = rcu_dereference_bh(n->ht_up);
241		off = stack[sdepth].off;
242		goto check_terminal;
243	}
244out:
245	return -1;
246
247deadloop:
248	net_warn_ratelimited("cls_u32: dead loop\n");
249	return -1;
250}
251
252static struct tc_u_hnode *
253u32_lookup_ht(struct tc_u_common *tp_c, u32 handle)
254{
255	struct tc_u_hnode *ht;
256
257	for (ht = rtnl_dereference(tp_c->hlist);
258	     ht;
259	     ht = rtnl_dereference(ht->next))
260		if (ht->handle == handle)
261			break;
262
263	return ht;
264}
265
266static struct tc_u_knode *
267u32_lookup_key(struct tc_u_hnode *ht, u32 handle)
268{
269	unsigned int sel;
270	struct tc_u_knode *n = NULL;
271
272	sel = TC_U32_HASH(handle);
273	if (sel > ht->divisor)
274		goto out;
275
276	for (n = rtnl_dereference(ht->ht[sel]);
277	     n;
278	     n = rtnl_dereference(n->next))
279		if (n->handle == handle)
280			break;
281out:
282	return n;
283}
284
285
286static unsigned long u32_get(struct tcf_proto *tp, u32 handle)
287{
288	struct tc_u_hnode *ht;
289	struct tc_u_common *tp_c = tp->data;
290
291	if (TC_U32_HTID(handle) == TC_U32_ROOT)
292		ht = rtnl_dereference(tp->root);
293	else
294		ht = u32_lookup_ht(tp_c, TC_U32_HTID(handle));
295
296	if (!ht)
297		return 0;
298
299	if (TC_U32_KEY(handle) == 0)
300		return (unsigned long)ht;
301
302	return (unsigned long)u32_lookup_key(ht, handle);
303}
304
305static u32 gen_new_htid(struct tc_u_common *tp_c)
306{
307	int i = 0x800;
308
309	/* hgenerator only used inside rtnl lock it is safe to increment
310	 * without read _copy_ update semantics
311	 */
312	do {
313		if (++tp_c->hgenerator == 0x7FF)
314			tp_c->hgenerator = 1;
315	} while (--i > 0 && u32_lookup_ht(tp_c, (tp_c->hgenerator|0x800)<<20));
316
317	return i > 0 ? (tp_c->hgenerator|0x800)<<20 : 0;
318}
319
320static int u32_init(struct tcf_proto *tp)
321{
322	struct tc_u_hnode *root_ht;
323	struct tc_u_common *tp_c;
324
325	tp_c = tp->q->u32_node;
326
327	root_ht = kzalloc(sizeof(*root_ht), GFP_KERNEL);
328	if (root_ht == NULL)
329		return -ENOBUFS;
330
331	root_ht->divisor = 0;
332	root_ht->refcnt++;
333	root_ht->handle = tp_c ? gen_new_htid(tp_c) : 0x80000000;
334	root_ht->prio = tp->prio;
335
336	if (tp_c == NULL) {
337		tp_c = kzalloc(sizeof(*tp_c), GFP_KERNEL);
338		if (tp_c == NULL) {
339			kfree(root_ht);
340			return -ENOBUFS;
341		}
342		tp_c->q = tp->q;
343		tp->q->u32_node = tp_c;
344	}
345
346	tp_c->refcnt++;
347	RCU_INIT_POINTER(root_ht->next, tp_c->hlist);
348	rcu_assign_pointer(tp_c->hlist, root_ht);
349	root_ht->tp_c = tp_c;
350
351	rcu_assign_pointer(tp->root, root_ht);
352	tp->data = tp_c;
353	return 0;
354}
355
356static int u32_destroy_key(struct tcf_proto *tp,
357			   struct tc_u_knode *n,
358			   bool free_pf)
359{
360	tcf_exts_destroy(&n->exts);
361	if (n->ht_down)
362		n->ht_down->refcnt--;
363#ifdef CONFIG_CLS_U32_PERF
364	if (free_pf)
365		free_percpu(n->pf);
366#endif
367#ifdef CONFIG_CLS_U32_MARK
368	if (free_pf)
369		free_percpu(n->pcpu_success);
370#endif
371	kfree(n);
372	return 0;
373}
374
375/* u32_delete_key_rcu should be called when free'ing a copied
376 * version of a tc_u_knode obtained from u32_init_knode(). When
377 * copies are obtained from u32_init_knode() the statistics are
378 * shared between the old and new copies to allow readers to
379 * continue to update the statistics during the copy. To support
380 * this the u32_delete_key_rcu variant does not free the percpu
381 * statistics.
382 */
383static void u32_delete_key_rcu(struct rcu_head *rcu)
384{
385	struct tc_u_knode *key = container_of(rcu, struct tc_u_knode, rcu);
386
387	u32_destroy_key(key->tp, key, false);
388}
389
390/* u32_delete_key_freepf_rcu is the rcu callback variant
391 * that free's the entire structure including the statistics
392 * percpu variables. Only use this if the key is not a copy
393 * returned by u32_init_knode(). See u32_delete_key_rcu()
394 * for the variant that should be used with keys return from
395 * u32_init_knode()
396 */
397static void u32_delete_key_freepf_rcu(struct rcu_head *rcu)
398{
399	struct tc_u_knode *key = container_of(rcu, struct tc_u_knode, rcu);
400
401	u32_destroy_key(key->tp, key, true);
402}
403
404static int u32_delete_key(struct tcf_proto *tp, struct tc_u_knode *key)
405{
406	struct tc_u_knode __rcu **kp;
407	struct tc_u_knode *pkp;
408	struct tc_u_hnode *ht = rtnl_dereference(key->ht_up);
409
410	if (ht) {
411		kp = &ht->ht[TC_U32_HASH(key->handle)];
412		for (pkp = rtnl_dereference(*kp); pkp;
413		     kp = &pkp->next, pkp = rtnl_dereference(*kp)) {
414			if (pkp == key) {
415				RCU_INIT_POINTER(*kp, key->next);
416
417				tcf_unbind_filter(tp, &key->res);
418				call_rcu(&key->rcu, u32_delete_key_freepf_rcu);
419				return 0;
420			}
421		}
422	}
423	WARN_ON(1);
424	return 0;
425}
426
427static void u32_clear_hnode(struct tcf_proto *tp, struct tc_u_hnode *ht)
428{
429	struct tc_u_knode *n;
430	unsigned int h;
431
432	for (h = 0; h <= ht->divisor; h++) {
433		while ((n = rtnl_dereference(ht->ht[h])) != NULL) {
434			RCU_INIT_POINTER(ht->ht[h],
435					 rtnl_dereference(n->next));
436			tcf_unbind_filter(tp, &n->res);
437			call_rcu(&n->rcu, u32_delete_key_freepf_rcu);
438		}
439	}
440}
441
442static int u32_destroy_hnode(struct tcf_proto *tp, struct tc_u_hnode *ht)
443{
444	struct tc_u_common *tp_c = tp->data;
445	struct tc_u_hnode __rcu **hn;
446	struct tc_u_hnode *phn;
447
448	WARN_ON(ht->refcnt);
449
450	u32_clear_hnode(tp, ht);
451
452	hn = &tp_c->hlist;
453	for (phn = rtnl_dereference(*hn);
454	     phn;
455	     hn = &phn->next, phn = rtnl_dereference(*hn)) {
456		if (phn == ht) {
457			RCU_INIT_POINTER(*hn, ht->next);
458			kfree_rcu(ht, rcu);
459			return 0;
460		}
461	}
462
463	return -ENOENT;
464}
465
466static bool ht_empty(struct tc_u_hnode *ht)
467{
468	unsigned int h;
469
470	for (h = 0; h <= ht->divisor; h++)
471		if (rcu_access_pointer(ht->ht[h]))
472			return false;
473
474	return true;
475}
476
477static bool u32_destroy(struct tcf_proto *tp, bool force)
478{
479	struct tc_u_common *tp_c = tp->data;
480	struct tc_u_hnode *root_ht = rtnl_dereference(tp->root);
481
482	WARN_ON(root_ht == NULL);
483
484	if (!force) {
485		if (root_ht) {
486			if (root_ht->refcnt > 1)
487				return false;
488			if (root_ht->refcnt == 1) {
489				if (!ht_empty(root_ht))
490					return false;
491			}
492		}
493
494		if (tp_c->refcnt > 1)
495			return false;
496
497		if (tp_c->refcnt == 1) {
498			struct tc_u_hnode *ht;
499
500			for (ht = rtnl_dereference(tp_c->hlist);
501			     ht;
502			     ht = rtnl_dereference(ht->next))
503				if (!ht_empty(ht))
504					return false;
505		}
506	}
507
508	if (root_ht && --root_ht->refcnt == 0)
509		u32_destroy_hnode(tp, root_ht);
510
511	if (--tp_c->refcnt == 0) {
512		struct tc_u_hnode *ht;
513
514		tp->q->u32_node = NULL;
515
516		for (ht = rtnl_dereference(tp_c->hlist);
517		     ht;
518		     ht = rtnl_dereference(ht->next)) {
519			ht->refcnt--;
520			u32_clear_hnode(tp, ht);
521		}
522
523		while ((ht = rtnl_dereference(tp_c->hlist)) != NULL) {
524			RCU_INIT_POINTER(tp_c->hlist, ht->next);
525			kfree_rcu(ht, rcu);
526		}
527
528		kfree(tp_c);
529	}
530
531	tp->data = NULL;
532	return true;
533}
534
535static int u32_delete(struct tcf_proto *tp, unsigned long arg)
536{
537	struct tc_u_hnode *ht = (struct tc_u_hnode *)arg;
538	struct tc_u_hnode *root_ht = rtnl_dereference(tp->root);
539
540	if (ht == NULL)
541		return 0;
542
543	if (TC_U32_KEY(ht->handle))
544		return u32_delete_key(tp, (struct tc_u_knode *)ht);
545
546	if (root_ht == ht)
547		return -EINVAL;
548
549	if (ht->refcnt == 1) {
550		ht->refcnt--;
551		u32_destroy_hnode(tp, ht);
552	} else {
553		return -EBUSY;
554	}
555
556	return 0;
557}
558
559#define NR_U32_NODE (1<<12)
560static u32 gen_new_kid(struct tc_u_hnode *ht, u32 handle)
561{
562	struct tc_u_knode *n;
563	unsigned long i;
564	unsigned long *bitmap = kzalloc(BITS_TO_LONGS(NR_U32_NODE) * sizeof(unsigned long),
565					GFP_KERNEL);
566	if (!bitmap)
567		return handle | 0xFFF;
568
569	for (n = rtnl_dereference(ht->ht[TC_U32_HASH(handle)]);
570	     n;
571	     n = rtnl_dereference(n->next))
572		set_bit(TC_U32_NODE(n->handle), bitmap);
573
574	i = find_next_zero_bit(bitmap, NR_U32_NODE, 0x800);
575	if (i >= NR_U32_NODE)
576		i = find_next_zero_bit(bitmap, NR_U32_NODE, 1);
577
578	kfree(bitmap);
579	return handle | (i >= NR_U32_NODE ? 0xFFF : i);
580}
581
582static const struct nla_policy u32_policy[TCA_U32_MAX + 1] = {
583	[TCA_U32_CLASSID]	= { .type = NLA_U32 },
584	[TCA_U32_HASH]		= { .type = NLA_U32 },
585	[TCA_U32_LINK]		= { .type = NLA_U32 },
586	[TCA_U32_DIVISOR]	= { .type = NLA_U32 },
587	[TCA_U32_SEL]		= { .len = sizeof(struct tc_u32_sel) },
588	[TCA_U32_INDEV]		= { .type = NLA_STRING, .len = IFNAMSIZ },
589	[TCA_U32_MARK]		= { .len = sizeof(struct tc_u32_mark) },
590};
591
592static int u32_set_parms(struct net *net, struct tcf_proto *tp,
593			 unsigned long base, struct tc_u_hnode *ht,
594			 struct tc_u_knode *n, struct nlattr **tb,
595			 struct nlattr *est, bool ovr)
596{
597	int err;
598	struct tcf_exts e;
599
600	tcf_exts_init(&e, TCA_U32_ACT, TCA_U32_POLICE);
601	err = tcf_exts_validate(net, tp, tb, est, &e, ovr);
602	if (err < 0)
603		return err;
604
605	err = -EINVAL;
606	if (tb[TCA_U32_LINK]) {
607		u32 handle = nla_get_u32(tb[TCA_U32_LINK]);
608		struct tc_u_hnode *ht_down = NULL, *ht_old;
609
610		if (TC_U32_KEY(handle))
611			goto errout;
612
613		if (handle) {
614			ht_down = u32_lookup_ht(ht->tp_c, handle);
615
616			if (ht_down == NULL)
617				goto errout;
618			ht_down->refcnt++;
619		}
620
621		ht_old = rtnl_dereference(n->ht_down);
622		rcu_assign_pointer(n->ht_down, ht_down);
623
624		if (ht_old)
625			ht_old->refcnt--;
626	}
627	if (tb[TCA_U32_CLASSID]) {
628		n->res.classid = nla_get_u32(tb[TCA_U32_CLASSID]);
629		tcf_bind_filter(tp, &n->res, base);
630	}
631
632#ifdef CONFIG_NET_CLS_IND
633	if (tb[TCA_U32_INDEV]) {
634		int ret;
635		ret = tcf_change_indev(net, tb[TCA_U32_INDEV]);
636		if (ret < 0)
637			goto errout;
638		n->ifindex = ret;
639	}
640#endif
641	tcf_exts_change(tp, &n->exts, &e);
642
643	return 0;
644errout:
645	tcf_exts_destroy(&e);
646	return err;
647}
648
649static void u32_replace_knode(struct tcf_proto *tp,
650			      struct tc_u_common *tp_c,
651			      struct tc_u_knode *n)
652{
653	struct tc_u_knode __rcu **ins;
654	struct tc_u_knode *pins;
655	struct tc_u_hnode *ht;
656
657	if (TC_U32_HTID(n->handle) == TC_U32_ROOT)
658		ht = rtnl_dereference(tp->root);
659	else
660		ht = u32_lookup_ht(tp_c, TC_U32_HTID(n->handle));
661
662	ins = &ht->ht[TC_U32_HASH(n->handle)];
663
664	/* The node must always exist for it to be replaced if this is not the
665	 * case then something went very wrong elsewhere.
666	 */
667	for (pins = rtnl_dereference(*ins); ;
668	     ins = &pins->next, pins = rtnl_dereference(*ins))
669		if (pins->handle == n->handle)
670			break;
671
672	RCU_INIT_POINTER(n->next, pins->next);
673	rcu_assign_pointer(*ins, n);
674}
675
676static struct tc_u_knode *u32_init_knode(struct tcf_proto *tp,
677					 struct tc_u_knode *n)
678{
679	struct tc_u_knode *new;
680	struct tc_u32_sel *s = &n->sel;
681
682	new = kzalloc(sizeof(*n) + s->nkeys*sizeof(struct tc_u32_key),
683		      GFP_KERNEL);
684
685	if (!new)
686		return NULL;
687
688	RCU_INIT_POINTER(new->next, n->next);
689	new->handle = n->handle;
690	RCU_INIT_POINTER(new->ht_up, n->ht_up);
691
692#ifdef CONFIG_NET_CLS_IND
693	new->ifindex = n->ifindex;
694#endif
695	new->fshift = n->fshift;
696	new->res = n->res;
697	RCU_INIT_POINTER(new->ht_down, n->ht_down);
698
699	/* bump reference count as long as we hold pointer to structure */
700	if (new->ht_down)
701		new->ht_down->refcnt++;
702
703#ifdef CONFIG_CLS_U32_PERF
704	/* Statistics may be incremented by readers during update
705	 * so we must keep them in tact. When the node is later destroyed
706	 * a special destroy call must be made to not free the pf memory.
707	 */
708	new->pf = n->pf;
709#endif
710
711#ifdef CONFIG_CLS_U32_MARK
712	new->val = n->val;
713	new->mask = n->mask;
714	/* Similarly success statistics must be moved as pointers */
715	new->pcpu_success = n->pcpu_success;
716#endif
717	new->tp = tp;
718	memcpy(&new->sel, s, sizeof(*s) + s->nkeys*sizeof(struct tc_u32_key));
719
720	tcf_exts_init(&new->exts, TCA_U32_ACT, TCA_U32_POLICE);
721
722	return new;
723}
724
725static int u32_change(struct net *net, struct sk_buff *in_skb,
726		      struct tcf_proto *tp, unsigned long base, u32 handle,
727		      struct nlattr **tca,
728		      unsigned long *arg, bool ovr)
729{
730	struct tc_u_common *tp_c = tp->data;
731	struct tc_u_hnode *ht;
732	struct tc_u_knode *n;
733	struct tc_u32_sel *s;
734	struct nlattr *opt = tca[TCA_OPTIONS];
735	struct nlattr *tb[TCA_U32_MAX + 1];
736	u32 htid;
737	int err;
738#ifdef CONFIG_CLS_U32_PERF
739	size_t size;
740#endif
741
742	if (opt == NULL)
743		return handle ? -EINVAL : 0;
744
745	err = nla_parse_nested(tb, TCA_U32_MAX, opt, u32_policy);
746	if (err < 0)
747		return err;
748
749	n = (struct tc_u_knode *)*arg;
750	if (n) {
751		struct tc_u_knode *new;
752
753		if (TC_U32_KEY(n->handle) == 0)
754			return -EINVAL;
755
756		new = u32_init_knode(tp, n);
757		if (!new)
758			return -ENOMEM;
759
760		err = u32_set_parms(net, tp, base,
761				    rtnl_dereference(n->ht_up), new, tb,
762				    tca[TCA_RATE], ovr);
763
764		if (err) {
765			u32_destroy_key(tp, new, false);
766			return err;
767		}
768
769		u32_replace_knode(tp, tp_c, new);
770		tcf_unbind_filter(tp, &n->res);
771		call_rcu(&n->rcu, u32_delete_key_rcu);
772		return 0;
773	}
774
775	if (tb[TCA_U32_DIVISOR]) {
776		unsigned int divisor = nla_get_u32(tb[TCA_U32_DIVISOR]);
777
778		if (--divisor > 0x100)
779			return -EINVAL;
780		if (TC_U32_KEY(handle))
781			return -EINVAL;
782		if (handle == 0) {
783			handle = gen_new_htid(tp->data);
784			if (handle == 0)
785				return -ENOMEM;
786		}
787		ht = kzalloc(sizeof(*ht) + divisor*sizeof(void *), GFP_KERNEL);
788		if (ht == NULL)
789			return -ENOBUFS;
790		ht->tp_c = tp_c;
791		ht->refcnt = 1;
792		ht->divisor = divisor;
793		ht->handle = handle;
794		ht->prio = tp->prio;
795		RCU_INIT_POINTER(ht->next, tp_c->hlist);
796		rcu_assign_pointer(tp_c->hlist, ht);
797		*arg = (unsigned long)ht;
798		return 0;
799	}
800
801	if (tb[TCA_U32_HASH]) {
802		htid = nla_get_u32(tb[TCA_U32_HASH]);
803		if (TC_U32_HTID(htid) == TC_U32_ROOT) {
804			ht = rtnl_dereference(tp->root);
805			htid = ht->handle;
806		} else {
807			ht = u32_lookup_ht(tp->data, TC_U32_HTID(htid));
808			if (ht == NULL)
809				return -EINVAL;
810		}
811	} else {
812		ht = rtnl_dereference(tp->root);
813		htid = ht->handle;
814	}
815
816	if (ht->divisor < TC_U32_HASH(htid))
817		return -EINVAL;
818
819	if (handle) {
820		if (TC_U32_HTID(handle) && TC_U32_HTID(handle^htid))
821			return -EINVAL;
822		handle = htid | TC_U32_NODE(handle);
823	} else
824		handle = gen_new_kid(ht, htid);
825
826	if (tb[TCA_U32_SEL] == NULL)
827		return -EINVAL;
828
829	s = nla_data(tb[TCA_U32_SEL]);
830
831	n = kzalloc(sizeof(*n) + s->nkeys*sizeof(struct tc_u32_key), GFP_KERNEL);
832	if (n == NULL)
833		return -ENOBUFS;
834
835#ifdef CONFIG_CLS_U32_PERF
836	size = sizeof(struct tc_u32_pcnt) + s->nkeys * sizeof(u64);
837	n->pf = __alloc_percpu(size, __alignof__(struct tc_u32_pcnt));
838	if (!n->pf) {
839		kfree(n);
840		return -ENOBUFS;
841	}
842#endif
843
844	memcpy(&n->sel, s, sizeof(*s) + s->nkeys*sizeof(struct tc_u32_key));
845	RCU_INIT_POINTER(n->ht_up, ht);
846	n->handle = handle;
847	n->fshift = s->hmask ? ffs(ntohl(s->hmask)) - 1 : 0;
848	tcf_exts_init(&n->exts, TCA_U32_ACT, TCA_U32_POLICE);
849	n->tp = tp;
850
851#ifdef CONFIG_CLS_U32_MARK
852	n->pcpu_success = alloc_percpu(u32);
853	if (!n->pcpu_success) {
854		err = -ENOMEM;
855		goto errout;
856	}
857
858	if (tb[TCA_U32_MARK]) {
859		struct tc_u32_mark *mark;
860
861		mark = nla_data(tb[TCA_U32_MARK]);
862		n->val = mark->val;
863		n->mask = mark->mask;
864	}
865#endif
866
867	err = u32_set_parms(net, tp, base, ht, n, tb, tca[TCA_RATE], ovr);
868	if (err == 0) {
869		struct tc_u_knode __rcu **ins;
870		struct tc_u_knode *pins;
871
872		ins = &ht->ht[TC_U32_HASH(handle)];
873		for (pins = rtnl_dereference(*ins); pins;
874		     ins = &pins->next, pins = rtnl_dereference(*ins))
875			if (TC_U32_NODE(handle) < TC_U32_NODE(pins->handle))
876				break;
877
878		RCU_INIT_POINTER(n->next, pins);
879		rcu_assign_pointer(*ins, n);
880
881		*arg = (unsigned long)n;
882		return 0;
883	}
884
885#ifdef CONFIG_CLS_U32_MARK
886	free_percpu(n->pcpu_success);
887errout:
888#endif
889
890#ifdef CONFIG_CLS_U32_PERF
891	free_percpu(n->pf);
892#endif
893	kfree(n);
894	return err;
895}
896
897static void u32_walk(struct tcf_proto *tp, struct tcf_walker *arg)
898{
899	struct tc_u_common *tp_c = tp->data;
900	struct tc_u_hnode *ht;
901	struct tc_u_knode *n;
902	unsigned int h;
903
904	if (arg->stop)
905		return;
906
907	for (ht = rtnl_dereference(tp_c->hlist);
908	     ht;
909	     ht = rtnl_dereference(ht->next)) {
910		if (ht->prio != tp->prio)
911			continue;
912		if (arg->count >= arg->skip) {
913			if (arg->fn(tp, (unsigned long)ht, arg) < 0) {
914				arg->stop = 1;
915				return;
916			}
917		}
918		arg->count++;
919		for (h = 0; h <= ht->divisor; h++) {
920			for (n = rtnl_dereference(ht->ht[h]);
921			     n;
922			     n = rtnl_dereference(n->next)) {
923				if (arg->count < arg->skip) {
924					arg->count++;
925					continue;
926				}
927				if (arg->fn(tp, (unsigned long)n, arg) < 0) {
928					arg->stop = 1;
929					return;
930				}
931				arg->count++;
932			}
933		}
934	}
935}
936
937static int u32_dump(struct net *net, struct tcf_proto *tp, unsigned long fh,
938		     struct sk_buff *skb, struct tcmsg *t)
939{
940	struct tc_u_knode *n = (struct tc_u_knode *)fh;
941	struct tc_u_hnode *ht_up, *ht_down;
942	struct nlattr *nest;
943
944	if (n == NULL)
945		return skb->len;
946
947	t->tcm_handle = n->handle;
948
949	nest = nla_nest_start(skb, TCA_OPTIONS);
950	if (nest == NULL)
951		goto nla_put_failure;
952
953	if (TC_U32_KEY(n->handle) == 0) {
954		struct tc_u_hnode *ht = (struct tc_u_hnode *)fh;
955		u32 divisor = ht->divisor + 1;
956
957		if (nla_put_u32(skb, TCA_U32_DIVISOR, divisor))
958			goto nla_put_failure;
959	} else {
960#ifdef CONFIG_CLS_U32_PERF
961		struct tc_u32_pcnt *gpf;
962		int cpu;
963#endif
964
965		if (nla_put(skb, TCA_U32_SEL,
966			    sizeof(n->sel) + n->sel.nkeys*sizeof(struct tc_u32_key),
967			    &n->sel))
968			goto nla_put_failure;
969
970		ht_up = rtnl_dereference(n->ht_up);
971		if (ht_up) {
972			u32 htid = n->handle & 0xFFFFF000;
973			if (nla_put_u32(skb, TCA_U32_HASH, htid))
974				goto nla_put_failure;
975		}
976		if (n->res.classid &&
977		    nla_put_u32(skb, TCA_U32_CLASSID, n->res.classid))
978			goto nla_put_failure;
979
980		ht_down = rtnl_dereference(n->ht_down);
981		if (ht_down &&
982		    nla_put_u32(skb, TCA_U32_LINK, ht_down->handle))
983			goto nla_put_failure;
984
985#ifdef CONFIG_CLS_U32_MARK
986		if ((n->val || n->mask)) {
987			struct tc_u32_mark mark = {.val = n->val,
988						   .mask = n->mask,
989						   .success = 0};
990			int cpum;
991
992			for_each_possible_cpu(cpum) {
993				__u32 cnt = *per_cpu_ptr(n->pcpu_success, cpum);
994
995				mark.success += cnt;
996			}
997
998			if (nla_put(skb, TCA_U32_MARK, sizeof(mark), &mark))
999				goto nla_put_failure;
1000		}
1001#endif
1002
1003		if (tcf_exts_dump(skb, &n->exts) < 0)
1004			goto nla_put_failure;
1005
1006#ifdef CONFIG_NET_CLS_IND
1007		if (n->ifindex) {
1008			struct net_device *dev;
1009			dev = __dev_get_by_index(net, n->ifindex);
1010			if (dev && nla_put_string(skb, TCA_U32_INDEV, dev->name))
1011				goto nla_put_failure;
1012		}
1013#endif
1014#ifdef CONFIG_CLS_U32_PERF
1015		gpf = kzalloc(sizeof(struct tc_u32_pcnt) +
1016			      n->sel.nkeys * sizeof(u64),
1017			      GFP_KERNEL);
1018		if (!gpf)
1019			goto nla_put_failure;
1020
1021		for_each_possible_cpu(cpu) {
1022			int i;
1023			struct tc_u32_pcnt *pf = per_cpu_ptr(n->pf, cpu);
1024
1025			gpf->rcnt += pf->rcnt;
1026			gpf->rhit += pf->rhit;
1027			for (i = 0; i < n->sel.nkeys; i++)
1028				gpf->kcnts[i] += pf->kcnts[i];
1029		}
1030
1031		if (nla_put(skb, TCA_U32_PCNT,
1032			    sizeof(struct tc_u32_pcnt) + n->sel.nkeys*sizeof(u64),
1033			    gpf)) {
1034			kfree(gpf);
1035			goto nla_put_failure;
1036		}
1037		kfree(gpf);
1038#endif
1039	}
1040
1041	nla_nest_end(skb, nest);
1042
1043	if (TC_U32_KEY(n->handle))
1044		if (tcf_exts_dump_stats(skb, &n->exts) < 0)
1045			goto nla_put_failure;
1046	return skb->len;
1047
1048nla_put_failure:
1049	nla_nest_cancel(skb, nest);
1050	return -1;
1051}
1052
1053static struct tcf_proto_ops cls_u32_ops __read_mostly = {
1054	.kind		=	"u32",
1055	.classify	=	u32_classify,
1056	.init		=	u32_init,
1057	.destroy	=	u32_destroy,
1058	.get		=	u32_get,
1059	.change		=	u32_change,
1060	.delete		=	u32_delete,
1061	.walk		=	u32_walk,
1062	.dump		=	u32_dump,
1063	.owner		=	THIS_MODULE,
1064};
1065
1066static int __init init_u32(void)
1067{
1068	pr_info("u32 classifier\n");
1069#ifdef CONFIG_CLS_U32_PERF
1070	pr_info("    Performance counters on\n");
1071#endif
1072#ifdef CONFIG_NET_CLS_IND
1073	pr_info("    input device check on\n");
1074#endif
1075#ifdef CONFIG_NET_CLS_ACT
1076	pr_info("    Actions configured\n");
1077#endif
1078	return register_tcf_proto_ops(&cls_u32_ops);
1079}
1080
1081static void __exit exit_u32(void)
1082{
1083	unregister_tcf_proto_ops(&cls_u32_ops);
1084}
1085
1086module_init(init_u32)
1087module_exit(exit_u32)
1088MODULE_LICENSE("GPL");
1089