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v3.5.6
  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/rtnetlink.h>
 40#include <linux/skbuff.h>
 
 41#include <net/netlink.h>
 42#include <net/act_api.h>
 43#include <net/pkt_cls.h>
 
 44
 45struct tc_u_knode {
 46	struct tc_u_knode	*next;
 47	u32			handle;
 48	struct tc_u_hnode	*ht_up;
 49	struct tcf_exts		exts;
 50#ifdef CONFIG_NET_CLS_IND
 51	char                     indev[IFNAMSIZ];
 52#endif
 53	u8			fshift;
 54	struct tcf_result	res;
 55	struct tc_u_hnode	*ht_down;
 56#ifdef CONFIG_CLS_U32_PERF
 57	struct tc_u32_pcnt	*pf;
 58#endif
 
 59#ifdef CONFIG_CLS_U32_MARK
 60	struct tc_u32_mark	mark;
 
 
 61#endif
 
 
 
 
 
 62	struct tc_u32_sel	sel;
 63};
 64
 65struct tc_u_hnode {
 66	struct tc_u_hnode	*next;
 67	u32			handle;
 68	u32			prio;
 69	struct tc_u_common	*tp_c;
 70	int			refcnt;
 71	unsigned int		divisor;
 72	struct tc_u_knode	*ht[1];
 
 
 
 
 73};
 74
 75struct tc_u_common {
 76	struct tc_u_hnode	*hlist;
 77	struct Qdisc		*q;
 78	int			refcnt;
 79	u32			hgenerator;
 80};
 81
 82static const struct tcf_ext_map u32_ext_map = {
 83	.action = TCA_U32_ACT,
 84	.police = TCA_U32_POLICE
 85};
 86
 87static inline unsigned int u32_hash_fold(__be32 key,
 88					 const struct tc_u32_sel *sel,
 89					 u8 fshift)
 90{
 91	unsigned int h = ntohl(key & sel->hmask) >> fshift;
 92
 93	return h;
 94}
 95
 96static int u32_classify(struct sk_buff *skb, const struct tcf_proto *tp, struct tcf_result *res)
 
 97{
 98	struct {
 99		struct tc_u_knode *knode;
100		unsigned int	  off;
101	} stack[TC_U32_MAXDEPTH];
102
103	struct tc_u_hnode *ht = (struct tc_u_hnode *)tp->root;
104	unsigned int off = skb_network_offset(skb);
105	struct tc_u_knode *n;
106	int sdepth = 0;
107	int off2 = 0;
108	int sel = 0;
109#ifdef CONFIG_CLS_U32_PERF
110	int j;
111#endif
112	int i, r;
113
114next_ht:
115	n = ht->ht[sel];
116
117next_knode:
118	if (n) {
119		struct tc_u32_key *key = n->sel.keys;
120
121#ifdef CONFIG_CLS_U32_PERF
122		n->pf->rcnt += 1;
123		j = 0;
124#endif
125
 
 
 
 
 
126#ifdef CONFIG_CLS_U32_MARK
127		if ((skb->mark & n->mark.mask) != n->mark.val) {
128			n = n->next;
129			goto next_knode;
130		} else {
131			n->mark.success++;
132		}
133#endif
134
135		for (i = n->sel.nkeys; i > 0; i--, key++) {
136			int toff = off + key->off + (off2 & key->offmask);
137			__be32 *data, hdata;
138
139			if (skb_headroom(skb) + toff > INT_MAX)
140				goto out;
141
142			data = skb_header_pointer(skb, toff, 4, &hdata);
143			if (!data)
144				goto out;
145			if ((*data ^ key->val) & key->mask) {
146				n = n->next;
147				goto next_knode;
148			}
149#ifdef CONFIG_CLS_U32_PERF
150			n->pf->kcnts[j] += 1;
151			j++;
152#endif
153		}
154		if (n->ht_down == NULL) {
 
 
155check_terminal:
156			if (n->sel.flags & TC_U32_TERMINAL) {
157
158				*res = n->res;
159#ifdef CONFIG_NET_CLS_IND
160				if (!tcf_match_indev(skb, n->indev)) {
161					n = n->next;
162					goto next_knode;
163				}
164#endif
165#ifdef CONFIG_CLS_U32_PERF
166				n->pf->rhit += 1;
167#endif
168				r = tcf_exts_exec(skb, &n->exts, res);
169				if (r < 0) {
170					n = n->next;
171					goto next_knode;
172				}
173
174				return r;
175			}
176			n = n->next;
177			goto next_knode;
178		}
179
180		/* PUSH */
181		if (sdepth >= TC_U32_MAXDEPTH)
182			goto deadloop;
183		stack[sdepth].knode = n;
184		stack[sdepth].off = off;
185		sdepth++;
186
187		ht = n->ht_down;
188		sel = 0;
189		if (ht->divisor) {
190			__be32 *data, hdata;
191
192			data = skb_header_pointer(skb, off + n->sel.hoff, 4,
193						  &hdata);
194			if (!data)
195				goto out;
196			sel = ht->divisor & u32_hash_fold(*data, &n->sel,
197							  n->fshift);
198		}
199		if (!(n->sel.flags & (TC_U32_VAROFFSET | TC_U32_OFFSET | TC_U32_EAT)))
200			goto next_ht;
201
202		if (n->sel.flags & (TC_U32_OFFSET | TC_U32_VAROFFSET)) {
203			off2 = n->sel.off + 3;
204			if (n->sel.flags & TC_U32_VAROFFSET) {
205				__be16 *data, hdata;
206
207				data = skb_header_pointer(skb,
208							  off + n->sel.offoff,
209							  2, &hdata);
210				if (!data)
211					goto out;
212				off2 += ntohs(n->sel.offmask & *data) >>
213					n->sel.offshift;
214			}
215			off2 &= ~3;
216		}
217		if (n->sel.flags & TC_U32_EAT) {
218			off += off2;
219			off2 = 0;
220		}
221
222		if (off < skb->len)
223			goto next_ht;
224	}
225
226	/* POP */
227	if (sdepth--) {
228		n = stack[sdepth].knode;
229		ht = n->ht_up;
230		off = stack[sdepth].off;
231		goto check_terminal;
232	}
233out:
234	return -1;
235
236deadloop:
237	net_warn_ratelimited("cls_u32: dead loop\n");
238	return -1;
239}
240
241static struct tc_u_hnode *
242u32_lookup_ht(struct tc_u_common *tp_c, u32 handle)
243{
244	struct tc_u_hnode *ht;
245
246	for (ht = tp_c->hlist; ht; ht = ht->next)
 
 
247		if (ht->handle == handle)
248			break;
249
250	return ht;
251}
252
253static struct tc_u_knode *
254u32_lookup_key(struct tc_u_hnode *ht, u32 handle)
255{
256	unsigned int sel;
257	struct tc_u_knode *n = NULL;
258
259	sel = TC_U32_HASH(handle);
260	if (sel > ht->divisor)
261		goto out;
262
263	for (n = ht->ht[sel]; n; n = n->next)
 
 
264		if (n->handle == handle)
265			break;
266out:
267	return n;
268}
269
270
271static unsigned long u32_get(struct tcf_proto *tp, u32 handle)
272{
273	struct tc_u_hnode *ht;
274	struct tc_u_common *tp_c = tp->data;
275
276	if (TC_U32_HTID(handle) == TC_U32_ROOT)
277		ht = tp->root;
278	else
279		ht = u32_lookup_ht(tp_c, TC_U32_HTID(handle));
280
281	if (!ht)
282		return 0;
283
284	if (TC_U32_KEY(handle) == 0)
285		return (unsigned long)ht;
286
287	return (unsigned long)u32_lookup_key(ht, handle);
288}
289
290static void u32_put(struct tcf_proto *tp, unsigned long f)
291{
292}
293
294static u32 gen_new_htid(struct tc_u_common *tp_c)
295{
296	int i = 0x800;
297
 
 
 
298	do {
299		if (++tp_c->hgenerator == 0x7FF)
300			tp_c->hgenerator = 1;
301	} while (--i > 0 && u32_lookup_ht(tp_c, (tp_c->hgenerator|0x800)<<20));
302
303	return i > 0 ? (tp_c->hgenerator|0x800)<<20 : 0;
304}
305
306static int u32_init(struct tcf_proto *tp)
307{
308	struct tc_u_hnode *root_ht;
309	struct tc_u_common *tp_c;
310
311	tp_c = tp->q->u32_node;
312
313	root_ht = kzalloc(sizeof(*root_ht), GFP_KERNEL);
314	if (root_ht == NULL)
315		return -ENOBUFS;
316
317	root_ht->divisor = 0;
318	root_ht->refcnt++;
319	root_ht->handle = tp_c ? gen_new_htid(tp_c) : 0x80000000;
320	root_ht->prio = tp->prio;
321
322	if (tp_c == NULL) {
323		tp_c = kzalloc(sizeof(*tp_c), GFP_KERNEL);
324		if (tp_c == NULL) {
325			kfree(root_ht);
326			return -ENOBUFS;
327		}
328		tp_c->q = tp->q;
329		tp->q->u32_node = tp_c;
330	}
331
332	tp_c->refcnt++;
333	root_ht->next = tp_c->hlist;
334	tp_c->hlist = root_ht;
335	root_ht->tp_c = tp_c;
336
337	tp->root = root_ht;
338	tp->data = tp_c;
339	return 0;
340}
341
342static int u32_destroy_key(struct tcf_proto *tp, struct tc_u_knode *n)
 
343{
344	tcf_unbind_filter(tp, &n->res);
345	tcf_exts_destroy(tp, &n->exts);
346	if (n->ht_down)
347		n->ht_down->refcnt--;
348#ifdef CONFIG_CLS_U32_PERF
349	kfree(n->pf);
 
 
 
 
 
350#endif
351	kfree(n);
352	return 0;
353}
354
355static int u32_delete_key(struct tcf_proto *tp, struct tc_u_knode* key)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
356{
357	struct tc_u_knode **kp;
358	struct tc_u_hnode *ht = key->ht_up;
 
 
 
 
 
 
 
 
359
360	if (ht) {
361		for (kp = &ht->ht[TC_U32_HASH(key->handle)]; *kp; kp = &(*kp)->next) {
362			if (*kp == key) {
363				tcf_tree_lock(tp);
364				*kp = key->next;
365				tcf_tree_unlock(tp);
366
367				u32_destroy_key(tp, key);
 
368				return 0;
369			}
370		}
371	}
372	WARN_ON(1);
373	return 0;
374}
375
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
376static void u32_clear_hnode(struct tcf_proto *tp, struct tc_u_hnode *ht)
377{
378	struct tc_u_knode *n;
379	unsigned int h;
380
381	for (h = 0; h <= ht->divisor; h++) {
382		while ((n = ht->ht[h]) != NULL) {
383			ht->ht[h] = n->next;
384
385			u32_destroy_key(tp, n);
 
 
386		}
387	}
388}
389
390static int u32_destroy_hnode(struct tcf_proto *tp, struct tc_u_hnode *ht)
391{
392	struct tc_u_common *tp_c = tp->data;
393	struct tc_u_hnode **hn;
 
394
395	WARN_ON(ht->refcnt);
396
397	u32_clear_hnode(tp, ht);
398
399	for (hn = &tp_c->hlist; *hn; hn = &(*hn)->next) {
400		if (*hn == ht) {
401			*hn = ht->next;
402			kfree(ht);
 
 
 
 
403			return 0;
404		}
405	}
406
407	WARN_ON(1);
408	return -ENOENT;
409}
410
411static void u32_destroy(struct tcf_proto *tp)
 
 
 
 
 
 
 
 
 
 
 
412{
413	struct tc_u_common *tp_c = tp->data;
414	struct tc_u_hnode *root_ht = tp->root;
415
416	WARN_ON(root_ht == NULL);
417
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
418	if (root_ht && --root_ht->refcnt == 0)
419		u32_destroy_hnode(tp, root_ht);
420
421	if (--tp_c->refcnt == 0) {
422		struct tc_u_hnode *ht;
423
424		tp->q->u32_node = NULL;
425
426		for (ht = tp_c->hlist; ht; ht = ht->next) {
 
 
427			ht->refcnt--;
428			u32_clear_hnode(tp, ht);
429		}
430
431		while ((ht = tp_c->hlist) != NULL) {
432			tp_c->hlist = ht->next;
433
434			WARN_ON(ht->refcnt != 0);
435
436			kfree(ht);
437		}
438
439		kfree(tp_c);
440	}
441
442	tp->data = NULL;
 
443}
444
445static int u32_delete(struct tcf_proto *tp, unsigned long arg)
446{
447	struct tc_u_hnode *ht = (struct tc_u_hnode *)arg;
 
448
449	if (ht == NULL)
450		return 0;
451
452	if (TC_U32_KEY(ht->handle))
 
453		return u32_delete_key(tp, (struct tc_u_knode *)ht);
 
454
455	if (tp->root == ht)
456		return -EINVAL;
457
458	if (ht->refcnt == 1) {
459		ht->refcnt--;
460		u32_destroy_hnode(tp, ht);
461	} else {
462		return -EBUSY;
463	}
464
465	return 0;
466}
467
 
468static u32 gen_new_kid(struct tc_u_hnode *ht, u32 handle)
469{
470	struct tc_u_knode *n;
471	unsigned int i = 0x7FF;
472
473	for (n = ht->ht[TC_U32_HASH(handle)]; n; n = n->next)
474		if (i < TC_U32_NODE(n->handle))
475			i = TC_U32_NODE(n->handle);
476	i++;
 
 
 
 
 
 
 
 
477
478	return handle | (i > 0xFFF ? 0xFFF : i);
 
479}
480
481static const struct nla_policy u32_policy[TCA_U32_MAX + 1] = {
482	[TCA_U32_CLASSID]	= { .type = NLA_U32 },
483	[TCA_U32_HASH]		= { .type = NLA_U32 },
484	[TCA_U32_LINK]		= { .type = NLA_U32 },
485	[TCA_U32_DIVISOR]	= { .type = NLA_U32 },
486	[TCA_U32_SEL]		= { .len = sizeof(struct tc_u32_sel) },
487	[TCA_U32_INDEV]		= { .type = NLA_STRING, .len = IFNAMSIZ },
488	[TCA_U32_MARK]		= { .len = sizeof(struct tc_u32_mark) },
 
489};
490
491static int u32_set_parms(struct tcf_proto *tp, unsigned long base,
492			 struct tc_u_hnode *ht,
493			 struct tc_u_knode *n, struct nlattr **tb,
494			 struct nlattr *est)
495{
496	int err;
497	struct tcf_exts e;
 
498
499	err = tcf_exts_validate(tp, tb, est, &e, &u32_ext_map);
500	if (err < 0)
501		return err;
 
 
 
502
503	err = -EINVAL;
504	if (tb[TCA_U32_LINK]) {
505		u32 handle = nla_get_u32(tb[TCA_U32_LINK]);
506		struct tc_u_hnode *ht_down = NULL, *ht_old;
507
508		if (TC_U32_KEY(handle))
509			goto errout;
510
511		if (handle) {
512			ht_down = u32_lookup_ht(ht->tp_c, handle);
513
514			if (ht_down == NULL)
515				goto errout;
516			ht_down->refcnt++;
517		}
518
519		tcf_tree_lock(tp);
520		ht_old = n->ht_down;
521		n->ht_down = ht_down;
522		tcf_tree_unlock(tp);
523
524		if (ht_old)
525			ht_old->refcnt--;
526	}
527	if (tb[TCA_U32_CLASSID]) {
528		n->res.classid = nla_get_u32(tb[TCA_U32_CLASSID]);
529		tcf_bind_filter(tp, &n->res, base);
530	}
531
532#ifdef CONFIG_NET_CLS_IND
533	if (tb[TCA_U32_INDEV]) {
534		err = tcf_change_indev(tp, n->indev, tb[TCA_U32_INDEV]);
535		if (err < 0)
 
536			goto errout;
 
537	}
538#endif
539	tcf_exts_change(tp, &n->exts, &e);
540
541	return 0;
542errout:
543	tcf_exts_destroy(tp, &e);
544	return err;
545}
546
547static int u32_change(struct tcf_proto *tp, unsigned long base, u32 handle,
548		      struct nlattr **tca,
549		      unsigned long *arg)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
550{
551	struct tc_u_common *tp_c = tp->data;
552	struct tc_u_hnode *ht;
553	struct tc_u_knode *n;
554	struct tc_u32_sel *s;
555	struct nlattr *opt = tca[TCA_OPTIONS];
556	struct nlattr *tb[TCA_U32_MAX + 1];
557	u32 htid;
558	int err;
 
 
 
559
560	if (opt == NULL)
561		return handle ? -EINVAL : 0;
562
563	err = nla_parse_nested(tb, TCA_U32_MAX, opt, u32_policy);
564	if (err < 0)
565		return err;
566
 
 
 
 
 
 
567	n = (struct tc_u_knode *)*arg;
568	if (n) {
 
 
569		if (TC_U32_KEY(n->handle) == 0)
570			return -EINVAL;
571
572		return u32_set_parms(tp, base, n->ht_up, n, tb, tca[TCA_RATE]);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
573	}
574
575	if (tb[TCA_U32_DIVISOR]) {
576		unsigned int divisor = nla_get_u32(tb[TCA_U32_DIVISOR]);
577
578		if (--divisor > 0x100)
579			return -EINVAL;
580		if (TC_U32_KEY(handle))
581			return -EINVAL;
582		if (handle == 0) {
583			handle = gen_new_htid(tp->data);
584			if (handle == 0)
585				return -ENOMEM;
586		}
587		ht = kzalloc(sizeof(*ht) + divisor*sizeof(void *), GFP_KERNEL);
588		if (ht == NULL)
589			return -ENOBUFS;
590		ht->tp_c = tp_c;
591		ht->refcnt = 1;
592		ht->divisor = divisor;
593		ht->handle = handle;
594		ht->prio = tp->prio;
595		ht->next = tp_c->hlist;
596		tp_c->hlist = ht;
 
 
 
 
 
 
 
597		*arg = (unsigned long)ht;
 
598		return 0;
599	}
600
601	if (tb[TCA_U32_HASH]) {
602		htid = nla_get_u32(tb[TCA_U32_HASH]);
603		if (TC_U32_HTID(htid) == TC_U32_ROOT) {
604			ht = tp->root;
605			htid = ht->handle;
606		} else {
607			ht = u32_lookup_ht(tp->data, TC_U32_HTID(htid));
608			if (ht == NULL)
609				return -EINVAL;
610		}
611	} else {
612		ht = tp->root;
613		htid = ht->handle;
614	}
615
616	if (ht->divisor < TC_U32_HASH(htid))
617		return -EINVAL;
618
619	if (handle) {
620		if (TC_U32_HTID(handle) && TC_U32_HTID(handle^htid))
621			return -EINVAL;
622		handle = htid | TC_U32_NODE(handle);
623	} else
624		handle = gen_new_kid(ht, htid);
625
626	if (tb[TCA_U32_SEL] == NULL)
627		return -EINVAL;
628
629	s = nla_data(tb[TCA_U32_SEL]);
630
631	n = kzalloc(sizeof(*n) + s->nkeys*sizeof(struct tc_u32_key), GFP_KERNEL);
632	if (n == NULL)
633		return -ENOBUFS;
634
635#ifdef CONFIG_CLS_U32_PERF
636	n->pf = kzalloc(sizeof(struct tc_u32_pcnt) + s->nkeys*sizeof(u64), GFP_KERNEL);
637	if (n->pf == NULL) {
 
638		kfree(n);
639		return -ENOBUFS;
640	}
641#endif
642
643	memcpy(&n->sel, s, sizeof(*s) + s->nkeys*sizeof(struct tc_u32_key));
644	n->ht_up = ht;
645	n->handle = handle;
646	n->fshift = s->hmask ? ffs(ntohl(s->hmask)) - 1 : 0;
 
 
 
 
 
 
647
648#ifdef CONFIG_CLS_U32_MARK
 
 
 
 
 
 
649	if (tb[TCA_U32_MARK]) {
650		struct tc_u32_mark *mark;
651
652		mark = nla_data(tb[TCA_U32_MARK]);
653		memcpy(&n->mark, mark, sizeof(struct tc_u32_mark));
654		n->mark.success = 0;
655	}
656#endif
657
658	err = u32_set_parms(tp, base, ht, n, tb, tca[TCA_RATE]);
659	if (err == 0) {
660		struct tc_u_knode **ins;
661		for (ins = &ht->ht[TC_U32_HASH(handle)]; *ins; ins = &(*ins)->next)
662			if (TC_U32_NODE(handle) < TC_U32_NODE((*ins)->handle))
663				break;
664
665		n->next = *ins;
666		tcf_tree_lock(tp);
667		*ins = n;
668		tcf_tree_unlock(tp);
 
 
 
 
 
669
 
 
670		*arg = (unsigned long)n;
671		return 0;
672	}
 
 
 
 
 
 
 
 
673#ifdef CONFIG_CLS_U32_PERF
674	kfree(n->pf);
675#endif
676	kfree(n);
677	return err;
678}
679
680static void u32_walk(struct tcf_proto *tp, struct tcf_walker *arg)
681{
682	struct tc_u_common *tp_c = tp->data;
683	struct tc_u_hnode *ht;
684	struct tc_u_knode *n;
685	unsigned int h;
686
687	if (arg->stop)
688		return;
689
690	for (ht = tp_c->hlist; ht; ht = ht->next) {
 
 
691		if (ht->prio != tp->prio)
692			continue;
693		if (arg->count >= arg->skip) {
694			if (arg->fn(tp, (unsigned long)ht, arg) < 0) {
695				arg->stop = 1;
696				return;
697			}
698		}
699		arg->count++;
700		for (h = 0; h <= ht->divisor; h++) {
701			for (n = ht->ht[h]; n; n = n->next) {
 
 
702				if (arg->count < arg->skip) {
703					arg->count++;
704					continue;
705				}
706				if (arg->fn(tp, (unsigned long)n, arg) < 0) {
707					arg->stop = 1;
708					return;
709				}
710				arg->count++;
711			}
712		}
713	}
714}
715
716static int u32_dump(struct tcf_proto *tp, unsigned long fh,
717		     struct sk_buff *skb, struct tcmsg *t)
718{
719	struct tc_u_knode *n = (struct tc_u_knode *)fh;
 
720	struct nlattr *nest;
721
722	if (n == NULL)
723		return skb->len;
724
725	t->tcm_handle = n->handle;
726
727	nest = nla_nest_start(skb, TCA_OPTIONS);
728	if (nest == NULL)
729		goto nla_put_failure;
730
731	if (TC_U32_KEY(n->handle) == 0) {
732		struct tc_u_hnode *ht = (struct tc_u_hnode *)fh;
733		u32 divisor = ht->divisor + 1;
734
735		if (nla_put_u32(skb, TCA_U32_DIVISOR, divisor))
736			goto nla_put_failure;
737	} else {
 
 
 
 
 
738		if (nla_put(skb, TCA_U32_SEL,
739			    sizeof(n->sel) + n->sel.nkeys*sizeof(struct tc_u32_key),
740			    &n->sel))
741			goto nla_put_failure;
742		if (n->ht_up) {
 
 
743			u32 htid = n->handle & 0xFFFFF000;
744			if (nla_put_u32(skb, TCA_U32_HASH, htid))
745				goto nla_put_failure;
746		}
747		if (n->res.classid &&
748		    nla_put_u32(skb, TCA_U32_CLASSID, n->res.classid))
749			goto nla_put_failure;
750		if (n->ht_down &&
751		    nla_put_u32(skb, TCA_U32_LINK, n->ht_down->handle))
 
 
752			goto nla_put_failure;
753
754#ifdef CONFIG_CLS_U32_MARK
755		if ((n->mark.val || n->mark.mask) &&
756		    nla_put(skb, TCA_U32_MARK, sizeof(n->mark), &n->mark))
757			goto nla_put_failure;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
758#endif
759
760		if (tcf_exts_dump(skb, &n->exts, &u32_ext_map) < 0)
761			goto nla_put_failure;
762
763#ifdef CONFIG_NET_CLS_IND
764		if (strlen(n->indev) &&
765		    nla_put_string(skb, TCA_U32_INDEV, n->indev))
766			goto nla_put_failure;
 
 
 
767#endif
768#ifdef CONFIG_CLS_U32_PERF
769		if (nla_put(skb, TCA_U32_PCNT,
770			    sizeof(struct tc_u32_pcnt) + n->sel.nkeys*sizeof(u64),
771			    n->pf))
 
772			goto nla_put_failure;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
773#endif
774	}
775
776	nla_nest_end(skb, nest);
777
778	if (TC_U32_KEY(n->handle))
779		if (tcf_exts_dump_stats(skb, &n->exts, &u32_ext_map) < 0)
780			goto nla_put_failure;
781	return skb->len;
782
783nla_put_failure:
784	nla_nest_cancel(skb, nest);
785	return -1;
786}
787
788static struct tcf_proto_ops cls_u32_ops __read_mostly = {
789	.kind		=	"u32",
790	.classify	=	u32_classify,
791	.init		=	u32_init,
792	.destroy	=	u32_destroy,
793	.get		=	u32_get,
794	.put		=	u32_put,
795	.change		=	u32_change,
796	.delete		=	u32_delete,
797	.walk		=	u32_walk,
798	.dump		=	u32_dump,
799	.owner		=	THIS_MODULE,
800};
801
802static int __init init_u32(void)
803{
804	pr_info("u32 classifier\n");
805#ifdef CONFIG_CLS_U32_PERF
806	pr_info("    Performance counters on\n");
807#endif
808#ifdef CONFIG_NET_CLS_IND
809	pr_info("    input device check on\n");
810#endif
811#ifdef CONFIG_NET_CLS_ACT
812	pr_info("    Actions configured\n");
813#endif
814	return register_tcf_proto_ops(&cls_u32_ops);
815}
816
817static void __exit exit_u32(void)
818{
819	unregister_tcf_proto_ops(&cls_u32_ops);
820}
821
822module_init(init_u32)
823module_exit(exit_u32)
824MODULE_LICENSE("GPL");
v4.10.11
   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#include <linux/netdevice.h>
  47
  48struct tc_u_knode {
  49	struct tc_u_knode __rcu	*next;
  50	u32			handle;
  51	struct tc_u_hnode __rcu	*ht_up;
  52	struct tcf_exts		exts;
  53#ifdef CONFIG_NET_CLS_IND
  54	int			ifindex;
  55#endif
  56	u8			fshift;
  57	struct tcf_result	res;
  58	struct tc_u_hnode __rcu	*ht_down;
  59#ifdef CONFIG_CLS_U32_PERF
  60	struct tc_u32_pcnt __percpu *pf;
  61#endif
  62	u32			flags;
  63#ifdef CONFIG_CLS_U32_MARK
  64	u32			val;
  65	u32			mask;
  66	u32 __percpu		*pcpu_success;
  67#endif
  68	struct tcf_proto	*tp;
  69	struct rcu_head		rcu;
  70	/* The 'sel' field MUST be the last field in structure to allow for
  71	 * tc_u32_keys allocated at end of structure.
  72	 */
  73	struct tc_u32_sel	sel;
  74};
  75
  76struct tc_u_hnode {
  77	struct tc_u_hnode __rcu	*next;
  78	u32			handle;
  79	u32			prio;
  80	struct tc_u_common	*tp_c;
  81	int			refcnt;
  82	unsigned int		divisor;
  83	struct rcu_head		rcu;
  84	/* The 'ht' field MUST be the last field in structure to allow for
  85	 * more entries allocated at end of structure.
  86	 */
  87	struct tc_u_knode __rcu	*ht[1];
  88};
  89
  90struct tc_u_common {
  91	struct tc_u_hnode __rcu	*hlist;
  92	struct Qdisc		*q;
  93	int			refcnt;
  94	u32			hgenerator;
  95	struct rcu_head		rcu;
 
 
 
 
  96};
  97
  98static inline unsigned int u32_hash_fold(__be32 key,
  99					 const struct tc_u32_sel *sel,
 100					 u8 fshift)
 101{
 102	unsigned int h = ntohl(key & sel->hmask) >> fshift;
 103
 104	return h;
 105}
 106
 107static int u32_classify(struct sk_buff *skb, const struct tcf_proto *tp,
 108			struct tcf_result *res)
 109{
 110	struct {
 111		struct tc_u_knode *knode;
 112		unsigned int	  off;
 113	} stack[TC_U32_MAXDEPTH];
 114
 115	struct tc_u_hnode *ht = rcu_dereference_bh(tp->root);
 116	unsigned int off = skb_network_offset(skb);
 117	struct tc_u_knode *n;
 118	int sdepth = 0;
 119	int off2 = 0;
 120	int sel = 0;
 121#ifdef CONFIG_CLS_U32_PERF
 122	int j;
 123#endif
 124	int i, r;
 125
 126next_ht:
 127	n = rcu_dereference_bh(ht->ht[sel]);
 128
 129next_knode:
 130	if (n) {
 131		struct tc_u32_key *key = n->sel.keys;
 132
 133#ifdef CONFIG_CLS_U32_PERF
 134		__this_cpu_inc(n->pf->rcnt);
 135		j = 0;
 136#endif
 137
 138		if (tc_skip_sw(n->flags)) {
 139			n = rcu_dereference_bh(n->next);
 140			goto next_knode;
 141		}
 142
 143#ifdef CONFIG_CLS_U32_MARK
 144		if ((skb->mark & n->mask) != n->val) {
 145			n = rcu_dereference_bh(n->next);
 146			goto next_knode;
 147		} else {
 148			__this_cpu_inc(*n->pcpu_success);
 149		}
 150#endif
 151
 152		for (i = n->sel.nkeys; i > 0; i--, key++) {
 153			int toff = off + key->off + (off2 & key->offmask);
 154			__be32 *data, hdata;
 155
 156			if (skb_headroom(skb) + toff > INT_MAX)
 157				goto out;
 158
 159			data = skb_header_pointer(skb, toff, 4, &hdata);
 160			if (!data)
 161				goto out;
 162			if ((*data ^ key->val) & key->mask) {
 163				n = rcu_dereference_bh(n->next);
 164				goto next_knode;
 165			}
 166#ifdef CONFIG_CLS_U32_PERF
 167			__this_cpu_inc(n->pf->kcnts[j]);
 168			j++;
 169#endif
 170		}
 171
 172		ht = rcu_dereference_bh(n->ht_down);
 173		if (!ht) {
 174check_terminal:
 175			if (n->sel.flags & TC_U32_TERMINAL) {
 176
 177				*res = n->res;
 178#ifdef CONFIG_NET_CLS_IND
 179				if (!tcf_match_indev(skb, n->ifindex)) {
 180					n = rcu_dereference_bh(n->next);
 181					goto next_knode;
 182				}
 183#endif
 184#ifdef CONFIG_CLS_U32_PERF
 185				__this_cpu_inc(n->pf->rhit);
 186#endif
 187				r = tcf_exts_exec(skb, &n->exts, res);
 188				if (r < 0) {
 189					n = rcu_dereference_bh(n->next);
 190					goto next_knode;
 191				}
 192
 193				return r;
 194			}
 195			n = rcu_dereference_bh(n->next);
 196			goto next_knode;
 197		}
 198
 199		/* PUSH */
 200		if (sdepth >= TC_U32_MAXDEPTH)
 201			goto deadloop;
 202		stack[sdepth].knode = n;
 203		stack[sdepth].off = off;
 204		sdepth++;
 205
 206		ht = rcu_dereference_bh(n->ht_down);
 207		sel = 0;
 208		if (ht->divisor) {
 209			__be32 *data, hdata;
 210
 211			data = skb_header_pointer(skb, off + n->sel.hoff, 4,
 212						  &hdata);
 213			if (!data)
 214				goto out;
 215			sel = ht->divisor & u32_hash_fold(*data, &n->sel,
 216							  n->fshift);
 217		}
 218		if (!(n->sel.flags & (TC_U32_VAROFFSET | TC_U32_OFFSET | TC_U32_EAT)))
 219			goto next_ht;
 220
 221		if (n->sel.flags & (TC_U32_OFFSET | TC_U32_VAROFFSET)) {
 222			off2 = n->sel.off + 3;
 223			if (n->sel.flags & TC_U32_VAROFFSET) {
 224				__be16 *data, hdata;
 225
 226				data = skb_header_pointer(skb,
 227							  off + n->sel.offoff,
 228							  2, &hdata);
 229				if (!data)
 230					goto out;
 231				off2 += ntohs(n->sel.offmask & *data) >>
 232					n->sel.offshift;
 233			}
 234			off2 &= ~3;
 235		}
 236		if (n->sel.flags & TC_U32_EAT) {
 237			off += off2;
 238			off2 = 0;
 239		}
 240
 241		if (off < skb->len)
 242			goto next_ht;
 243	}
 244
 245	/* POP */
 246	if (sdepth--) {
 247		n = stack[sdepth].knode;
 248		ht = rcu_dereference_bh(n->ht_up);
 249		off = stack[sdepth].off;
 250		goto check_terminal;
 251	}
 252out:
 253	return -1;
 254
 255deadloop:
 256	net_warn_ratelimited("cls_u32: dead loop\n");
 257	return -1;
 258}
 259
 260static struct tc_u_hnode *u32_lookup_ht(struct tc_u_common *tp_c, u32 handle)
 
 261{
 262	struct tc_u_hnode *ht;
 263
 264	for (ht = rtnl_dereference(tp_c->hlist);
 265	     ht;
 266	     ht = rtnl_dereference(ht->next))
 267		if (ht->handle == handle)
 268			break;
 269
 270	return ht;
 271}
 272
 273static struct tc_u_knode *u32_lookup_key(struct tc_u_hnode *ht, u32 handle)
 
 274{
 275	unsigned int sel;
 276	struct tc_u_knode *n = NULL;
 277
 278	sel = TC_U32_HASH(handle);
 279	if (sel > ht->divisor)
 280		goto out;
 281
 282	for (n = rtnl_dereference(ht->ht[sel]);
 283	     n;
 284	     n = rtnl_dereference(n->next))
 285		if (n->handle == handle)
 286			break;
 287out:
 288	return n;
 289}
 290
 291
 292static unsigned long u32_get(struct tcf_proto *tp, u32 handle)
 293{
 294	struct tc_u_hnode *ht;
 295	struct tc_u_common *tp_c = tp->data;
 296
 297	if (TC_U32_HTID(handle) == TC_U32_ROOT)
 298		ht = rtnl_dereference(tp->root);
 299	else
 300		ht = u32_lookup_ht(tp_c, TC_U32_HTID(handle));
 301
 302	if (!ht)
 303		return 0;
 304
 305	if (TC_U32_KEY(handle) == 0)
 306		return (unsigned long)ht;
 307
 308	return (unsigned long)u32_lookup_key(ht, handle);
 309}
 310
 
 
 
 
 311static u32 gen_new_htid(struct tc_u_common *tp_c)
 312{
 313	int i = 0x800;
 314
 315	/* hgenerator only used inside rtnl lock it is safe to increment
 316	 * without read _copy_ update semantics
 317	 */
 318	do {
 319		if (++tp_c->hgenerator == 0x7FF)
 320			tp_c->hgenerator = 1;
 321	} while (--i > 0 && u32_lookup_ht(tp_c, (tp_c->hgenerator|0x800)<<20));
 322
 323	return i > 0 ? (tp_c->hgenerator|0x800)<<20 : 0;
 324}
 325
 326static int u32_init(struct tcf_proto *tp)
 327{
 328	struct tc_u_hnode *root_ht;
 329	struct tc_u_common *tp_c;
 330
 331	tp_c = tp->q->u32_node;
 332
 333	root_ht = kzalloc(sizeof(*root_ht), GFP_KERNEL);
 334	if (root_ht == NULL)
 335		return -ENOBUFS;
 336
 337	root_ht->divisor = 0;
 338	root_ht->refcnt++;
 339	root_ht->handle = tp_c ? gen_new_htid(tp_c) : 0x80000000;
 340	root_ht->prio = tp->prio;
 341
 342	if (tp_c == NULL) {
 343		tp_c = kzalloc(sizeof(*tp_c), GFP_KERNEL);
 344		if (tp_c == NULL) {
 345			kfree(root_ht);
 346			return -ENOBUFS;
 347		}
 348		tp_c->q = tp->q;
 349		tp->q->u32_node = tp_c;
 350	}
 351
 352	tp_c->refcnt++;
 353	RCU_INIT_POINTER(root_ht->next, tp_c->hlist);
 354	rcu_assign_pointer(tp_c->hlist, root_ht);
 355	root_ht->tp_c = tp_c;
 356
 357	rcu_assign_pointer(tp->root, root_ht);
 358	tp->data = tp_c;
 359	return 0;
 360}
 361
 362static int u32_destroy_key(struct tcf_proto *tp, struct tc_u_knode *n,
 363			   bool free_pf)
 364{
 365	tcf_exts_destroy(&n->exts);
 
 366	if (n->ht_down)
 367		n->ht_down->refcnt--;
 368#ifdef CONFIG_CLS_U32_PERF
 369	if (free_pf)
 370		free_percpu(n->pf);
 371#endif
 372#ifdef CONFIG_CLS_U32_MARK
 373	if (free_pf)
 374		free_percpu(n->pcpu_success);
 375#endif
 376	kfree(n);
 377	return 0;
 378}
 379
 380/* u32_delete_key_rcu should be called when free'ing a copied
 381 * version of a tc_u_knode obtained from u32_init_knode(). When
 382 * copies are obtained from u32_init_knode() the statistics are
 383 * shared between the old and new copies to allow readers to
 384 * continue to update the statistics during the copy. To support
 385 * this the u32_delete_key_rcu variant does not free the percpu
 386 * statistics.
 387 */
 388static void u32_delete_key_rcu(struct rcu_head *rcu)
 389{
 390	struct tc_u_knode *key = container_of(rcu, struct tc_u_knode, rcu);
 391
 392	u32_destroy_key(key->tp, key, false);
 393}
 394
 395/* u32_delete_key_freepf_rcu is the rcu callback variant
 396 * that free's the entire structure including the statistics
 397 * percpu variables. Only use this if the key is not a copy
 398 * returned by u32_init_knode(). See u32_delete_key_rcu()
 399 * for the variant that should be used with keys return from
 400 * u32_init_knode()
 401 */
 402static void u32_delete_key_freepf_rcu(struct rcu_head *rcu)
 403{
 404	struct tc_u_knode *key = container_of(rcu, struct tc_u_knode, rcu);
 405
 406	u32_destroy_key(key->tp, key, true);
 407}
 408
 409static int u32_delete_key(struct tcf_proto *tp, struct tc_u_knode *key)
 410{
 411	struct tc_u_knode __rcu **kp;
 412	struct tc_u_knode *pkp;
 413	struct tc_u_hnode *ht = rtnl_dereference(key->ht_up);
 414
 415	if (ht) {
 416		kp = &ht->ht[TC_U32_HASH(key->handle)];
 417		for (pkp = rtnl_dereference(*kp); pkp;
 418		     kp = &pkp->next, pkp = rtnl_dereference(*kp)) {
 419			if (pkp == key) {
 420				RCU_INIT_POINTER(*kp, key->next);
 421
 422				tcf_unbind_filter(tp, &key->res);
 423				call_rcu(&key->rcu, u32_delete_key_freepf_rcu);
 424				return 0;
 425			}
 426		}
 427	}
 428	WARN_ON(1);
 429	return 0;
 430}
 431
 432static void u32_remove_hw_knode(struct tcf_proto *tp, u32 handle)
 433{
 434	struct net_device *dev = tp->q->dev_queue->dev;
 435	struct tc_cls_u32_offload u32_offload = {0};
 436	struct tc_to_netdev offload;
 437
 438	offload.type = TC_SETUP_CLSU32;
 439	offload.cls_u32 = &u32_offload;
 440
 441	if (tc_should_offload(dev, tp, 0)) {
 442		offload.cls_u32->command = TC_CLSU32_DELETE_KNODE;
 443		offload.cls_u32->knode.handle = handle;
 444		dev->netdev_ops->ndo_setup_tc(dev, tp->q->handle,
 445					      tp->protocol, &offload);
 446	}
 447}
 448
 449static int u32_replace_hw_hnode(struct tcf_proto *tp, struct tc_u_hnode *h,
 450				u32 flags)
 451{
 452	struct net_device *dev = tp->q->dev_queue->dev;
 453	struct tc_cls_u32_offload u32_offload = {0};
 454	struct tc_to_netdev offload;
 455	int err;
 456
 457	if (!tc_should_offload(dev, tp, flags))
 458		return tc_skip_sw(flags) ? -EINVAL : 0;
 459
 460	offload.type = TC_SETUP_CLSU32;
 461	offload.cls_u32 = &u32_offload;
 462
 463	offload.cls_u32->command = TC_CLSU32_NEW_HNODE;
 464	offload.cls_u32->hnode.divisor = h->divisor;
 465	offload.cls_u32->hnode.handle = h->handle;
 466	offload.cls_u32->hnode.prio = h->prio;
 467
 468	err = dev->netdev_ops->ndo_setup_tc(dev, tp->q->handle,
 469					    tp->protocol, &offload);
 470	if (tc_skip_sw(flags))
 471		return err;
 472
 473	return 0;
 474}
 475
 476static void u32_clear_hw_hnode(struct tcf_proto *tp, struct tc_u_hnode *h)
 477{
 478	struct net_device *dev = tp->q->dev_queue->dev;
 479	struct tc_cls_u32_offload u32_offload = {0};
 480	struct tc_to_netdev offload;
 481
 482	offload.type = TC_SETUP_CLSU32;
 483	offload.cls_u32 = &u32_offload;
 484
 485	if (tc_should_offload(dev, tp, 0)) {
 486		offload.cls_u32->command = TC_CLSU32_DELETE_HNODE;
 487		offload.cls_u32->hnode.divisor = h->divisor;
 488		offload.cls_u32->hnode.handle = h->handle;
 489		offload.cls_u32->hnode.prio = h->prio;
 490
 491		dev->netdev_ops->ndo_setup_tc(dev, tp->q->handle,
 492					      tp->protocol, &offload);
 493	}
 494}
 495
 496static int u32_replace_hw_knode(struct tcf_proto *tp, struct tc_u_knode *n,
 497				u32 flags)
 498{
 499	struct net_device *dev = tp->q->dev_queue->dev;
 500	struct tc_cls_u32_offload u32_offload = {0};
 501	struct tc_to_netdev offload;
 502	int err;
 503
 504	offload.type = TC_SETUP_CLSU32;
 505	offload.cls_u32 = &u32_offload;
 506
 507	if (!tc_should_offload(dev, tp, flags))
 508		return tc_skip_sw(flags) ? -EINVAL : 0;
 509
 510	offload.cls_u32->command = TC_CLSU32_REPLACE_KNODE;
 511	offload.cls_u32->knode.handle = n->handle;
 512	offload.cls_u32->knode.fshift = n->fshift;
 513#ifdef CONFIG_CLS_U32_MARK
 514	offload.cls_u32->knode.val = n->val;
 515	offload.cls_u32->knode.mask = n->mask;
 516#else
 517	offload.cls_u32->knode.val = 0;
 518	offload.cls_u32->knode.mask = 0;
 519#endif
 520	offload.cls_u32->knode.sel = &n->sel;
 521	offload.cls_u32->knode.exts = &n->exts;
 522	if (n->ht_down)
 523		offload.cls_u32->knode.link_handle = n->ht_down->handle;
 524
 525	err = dev->netdev_ops->ndo_setup_tc(dev, tp->q->handle,
 526					    tp->protocol, &offload);
 527	if (tc_skip_sw(flags))
 528		return err;
 529
 530	return 0;
 531}
 532
 533static void u32_clear_hnode(struct tcf_proto *tp, struct tc_u_hnode *ht)
 534{
 535	struct tc_u_knode *n;
 536	unsigned int h;
 537
 538	for (h = 0; h <= ht->divisor; h++) {
 539		while ((n = rtnl_dereference(ht->ht[h])) != NULL) {
 540			RCU_INIT_POINTER(ht->ht[h],
 541					 rtnl_dereference(n->next));
 542			tcf_unbind_filter(tp, &n->res);
 543			u32_remove_hw_knode(tp, n->handle);
 544			call_rcu(&n->rcu, u32_delete_key_freepf_rcu);
 545		}
 546	}
 547}
 548
 549static int u32_destroy_hnode(struct tcf_proto *tp, struct tc_u_hnode *ht)
 550{
 551	struct tc_u_common *tp_c = tp->data;
 552	struct tc_u_hnode __rcu **hn;
 553	struct tc_u_hnode *phn;
 554
 555	WARN_ON(ht->refcnt);
 556
 557	u32_clear_hnode(tp, ht);
 558
 559	hn = &tp_c->hlist;
 560	for (phn = rtnl_dereference(*hn);
 561	     phn;
 562	     hn = &phn->next, phn = rtnl_dereference(*hn)) {
 563		if (phn == ht) {
 564			u32_clear_hw_hnode(tp, ht);
 565			RCU_INIT_POINTER(*hn, ht->next);
 566			kfree_rcu(ht, rcu);
 567			return 0;
 568		}
 569	}
 570
 
 571	return -ENOENT;
 572}
 573
 574static bool ht_empty(struct tc_u_hnode *ht)
 575{
 576	unsigned int h;
 577
 578	for (h = 0; h <= ht->divisor; h++)
 579		if (rcu_access_pointer(ht->ht[h]))
 580			return false;
 581
 582	return true;
 583}
 584
 585static bool u32_destroy(struct tcf_proto *tp, bool force)
 586{
 587	struct tc_u_common *tp_c = tp->data;
 588	struct tc_u_hnode *root_ht = rtnl_dereference(tp->root);
 589
 590	WARN_ON(root_ht == NULL);
 591
 592	if (!force) {
 593		if (root_ht) {
 594			if (root_ht->refcnt > 1)
 595				return false;
 596			if (root_ht->refcnt == 1) {
 597				if (!ht_empty(root_ht))
 598					return false;
 599			}
 600		}
 601
 602		if (tp_c->refcnt > 1)
 603			return false;
 604
 605		if (tp_c->refcnt == 1) {
 606			struct tc_u_hnode *ht;
 607
 608			for (ht = rtnl_dereference(tp_c->hlist);
 609			     ht;
 610			     ht = rtnl_dereference(ht->next))
 611				if (!ht_empty(ht))
 612					return false;
 613		}
 614	}
 615
 616	if (root_ht && --root_ht->refcnt == 0)
 617		u32_destroy_hnode(tp, root_ht);
 618
 619	if (--tp_c->refcnt == 0) {
 620		struct tc_u_hnode *ht;
 621
 622		tp->q->u32_node = NULL;
 623
 624		for (ht = rtnl_dereference(tp_c->hlist);
 625		     ht;
 626		     ht = rtnl_dereference(ht->next)) {
 627			ht->refcnt--;
 628			u32_clear_hnode(tp, ht);
 629		}
 630
 631		while ((ht = rtnl_dereference(tp_c->hlist)) != NULL) {
 632			RCU_INIT_POINTER(tp_c->hlist, ht->next);
 633			kfree_rcu(ht, rcu);
 
 
 
 634		}
 635
 636		kfree(tp_c);
 637	}
 638
 639	tp->data = NULL;
 640	return true;
 641}
 642
 643static int u32_delete(struct tcf_proto *tp, unsigned long arg)
 644{
 645	struct tc_u_hnode *ht = (struct tc_u_hnode *)arg;
 646	struct tc_u_hnode *root_ht = rtnl_dereference(tp->root);
 647
 648	if (ht == NULL)
 649		return 0;
 650
 651	if (TC_U32_KEY(ht->handle)) {
 652		u32_remove_hw_knode(tp, ht->handle);
 653		return u32_delete_key(tp, (struct tc_u_knode *)ht);
 654	}
 655
 656	if (root_ht == ht)
 657		return -EINVAL;
 658
 659	if (ht->refcnt == 1) {
 660		ht->refcnt--;
 661		u32_destroy_hnode(tp, ht);
 662	} else {
 663		return -EBUSY;
 664	}
 665
 666	return 0;
 667}
 668
 669#define NR_U32_NODE (1<<12)
 670static u32 gen_new_kid(struct tc_u_hnode *ht, u32 handle)
 671{
 672	struct tc_u_knode *n;
 673	unsigned long i;
 674	unsigned long *bitmap = kzalloc(BITS_TO_LONGS(NR_U32_NODE) * sizeof(unsigned long),
 675					GFP_KERNEL);
 676	if (!bitmap)
 677		return handle | 0xFFF;
 678
 679	for (n = rtnl_dereference(ht->ht[TC_U32_HASH(handle)]);
 680	     n;
 681	     n = rtnl_dereference(n->next))
 682		set_bit(TC_U32_NODE(n->handle), bitmap);
 683
 684	i = find_next_zero_bit(bitmap, NR_U32_NODE, 0x800);
 685	if (i >= NR_U32_NODE)
 686		i = find_next_zero_bit(bitmap, NR_U32_NODE, 1);
 687
 688	kfree(bitmap);
 689	return handle | (i >= NR_U32_NODE ? 0xFFF : i);
 690}
 691
 692static const struct nla_policy u32_policy[TCA_U32_MAX + 1] = {
 693	[TCA_U32_CLASSID]	= { .type = NLA_U32 },
 694	[TCA_U32_HASH]		= { .type = NLA_U32 },
 695	[TCA_U32_LINK]		= { .type = NLA_U32 },
 696	[TCA_U32_DIVISOR]	= { .type = NLA_U32 },
 697	[TCA_U32_SEL]		= { .len = sizeof(struct tc_u32_sel) },
 698	[TCA_U32_INDEV]		= { .type = NLA_STRING, .len = IFNAMSIZ },
 699	[TCA_U32_MARK]		= { .len = sizeof(struct tc_u32_mark) },
 700	[TCA_U32_FLAGS]		= { .type = NLA_U32 },
 701};
 702
 703static int u32_set_parms(struct net *net, struct tcf_proto *tp,
 704			 unsigned long base, struct tc_u_hnode *ht,
 705			 struct tc_u_knode *n, struct nlattr **tb,
 706			 struct nlattr *est, bool ovr)
 707{
 
 708	struct tcf_exts e;
 709	int err;
 710
 711	err = tcf_exts_init(&e, TCA_U32_ACT, TCA_U32_POLICE);
 712	if (err < 0)
 713		return err;
 714	err = tcf_exts_validate(net, tp, tb, est, &e, ovr);
 715	if (err < 0)
 716		goto errout;
 717
 718	err = -EINVAL;
 719	if (tb[TCA_U32_LINK]) {
 720		u32 handle = nla_get_u32(tb[TCA_U32_LINK]);
 721		struct tc_u_hnode *ht_down = NULL, *ht_old;
 722
 723		if (TC_U32_KEY(handle))
 724			goto errout;
 725
 726		if (handle) {
 727			ht_down = u32_lookup_ht(ht->tp_c, handle);
 728
 729			if (ht_down == NULL)
 730				goto errout;
 731			ht_down->refcnt++;
 732		}
 733
 734		ht_old = rtnl_dereference(n->ht_down);
 735		rcu_assign_pointer(n->ht_down, ht_down);
 
 
 736
 737		if (ht_old)
 738			ht_old->refcnt--;
 739	}
 740	if (tb[TCA_U32_CLASSID]) {
 741		n->res.classid = nla_get_u32(tb[TCA_U32_CLASSID]);
 742		tcf_bind_filter(tp, &n->res, base);
 743	}
 744
 745#ifdef CONFIG_NET_CLS_IND
 746	if (tb[TCA_U32_INDEV]) {
 747		int ret;
 748		ret = tcf_change_indev(net, tb[TCA_U32_INDEV]);
 749		if (ret < 0)
 750			goto errout;
 751		n->ifindex = ret;
 752	}
 753#endif
 754	tcf_exts_change(tp, &n->exts, &e);
 755
 756	return 0;
 757errout:
 758	tcf_exts_destroy(&e);
 759	return err;
 760}
 761
 762static void u32_replace_knode(struct tcf_proto *tp, struct tc_u_common *tp_c,
 763			      struct tc_u_knode *n)
 764{
 765	struct tc_u_knode __rcu **ins;
 766	struct tc_u_knode *pins;
 767	struct tc_u_hnode *ht;
 768
 769	if (TC_U32_HTID(n->handle) == TC_U32_ROOT)
 770		ht = rtnl_dereference(tp->root);
 771	else
 772		ht = u32_lookup_ht(tp_c, TC_U32_HTID(n->handle));
 773
 774	ins = &ht->ht[TC_U32_HASH(n->handle)];
 775
 776	/* The node must always exist for it to be replaced if this is not the
 777	 * case then something went very wrong elsewhere.
 778	 */
 779	for (pins = rtnl_dereference(*ins); ;
 780	     ins = &pins->next, pins = rtnl_dereference(*ins))
 781		if (pins->handle == n->handle)
 782			break;
 783
 784	RCU_INIT_POINTER(n->next, pins->next);
 785	rcu_assign_pointer(*ins, n);
 786}
 787
 788static struct tc_u_knode *u32_init_knode(struct tcf_proto *tp,
 789					 struct tc_u_knode *n)
 790{
 791	struct tc_u_knode *new;
 792	struct tc_u32_sel *s = &n->sel;
 793
 794	new = kzalloc(sizeof(*n) + s->nkeys*sizeof(struct tc_u32_key),
 795		      GFP_KERNEL);
 796
 797	if (!new)
 798		return NULL;
 799
 800	RCU_INIT_POINTER(new->next, n->next);
 801	new->handle = n->handle;
 802	RCU_INIT_POINTER(new->ht_up, n->ht_up);
 803
 804#ifdef CONFIG_NET_CLS_IND
 805	new->ifindex = n->ifindex;
 806#endif
 807	new->fshift = n->fshift;
 808	new->res = n->res;
 809	new->flags = n->flags;
 810	RCU_INIT_POINTER(new->ht_down, n->ht_down);
 811
 812	/* bump reference count as long as we hold pointer to structure */
 813	if (new->ht_down)
 814		new->ht_down->refcnt++;
 815
 816#ifdef CONFIG_CLS_U32_PERF
 817	/* Statistics may be incremented by readers during update
 818	 * so we must keep them in tact. When the node is later destroyed
 819	 * a special destroy call must be made to not free the pf memory.
 820	 */
 821	new->pf = n->pf;
 822#endif
 823
 824#ifdef CONFIG_CLS_U32_MARK
 825	new->val = n->val;
 826	new->mask = n->mask;
 827	/* Similarly success statistics must be moved as pointers */
 828	new->pcpu_success = n->pcpu_success;
 829#endif
 830	new->tp = tp;
 831	memcpy(&new->sel, s, sizeof(*s) + s->nkeys*sizeof(struct tc_u32_key));
 832
 833	if (tcf_exts_init(&new->exts, TCA_U32_ACT, TCA_U32_POLICE)) {
 834		kfree(new);
 835		return NULL;
 836	}
 837
 838	return new;
 839}
 840
 841static int u32_change(struct net *net, struct sk_buff *in_skb,
 842		      struct tcf_proto *tp, unsigned long base, u32 handle,
 843		      struct nlattr **tca, unsigned long *arg, bool ovr)
 844{
 845	struct tc_u_common *tp_c = tp->data;
 846	struct tc_u_hnode *ht;
 847	struct tc_u_knode *n;
 848	struct tc_u32_sel *s;
 849	struct nlattr *opt = tca[TCA_OPTIONS];
 850	struct nlattr *tb[TCA_U32_MAX + 1];
 851	u32 htid, flags = 0;
 852	int err;
 853#ifdef CONFIG_CLS_U32_PERF
 854	size_t size;
 855#endif
 856
 857	if (opt == NULL)
 858		return handle ? -EINVAL : 0;
 859
 860	err = nla_parse_nested(tb, TCA_U32_MAX, opt, u32_policy);
 861	if (err < 0)
 862		return err;
 863
 864	if (tb[TCA_U32_FLAGS]) {
 865		flags = nla_get_u32(tb[TCA_U32_FLAGS]);
 866		if (!tc_flags_valid(flags))
 867			return -EINVAL;
 868	}
 869
 870	n = (struct tc_u_knode *)*arg;
 871	if (n) {
 872		struct tc_u_knode *new;
 873
 874		if (TC_U32_KEY(n->handle) == 0)
 875			return -EINVAL;
 876
 877		if (n->flags != flags)
 878			return -EINVAL;
 879
 880		new = u32_init_knode(tp, n);
 881		if (!new)
 882			return -ENOMEM;
 883
 884		err = u32_set_parms(net, tp, base,
 885				    rtnl_dereference(n->ht_up), new, tb,
 886				    tca[TCA_RATE], ovr);
 887
 888		if (err) {
 889			u32_destroy_key(tp, new, false);
 890			return err;
 891		}
 892
 893		err = u32_replace_hw_knode(tp, new, flags);
 894		if (err) {
 895			u32_destroy_key(tp, new, false);
 896			return err;
 897		}
 898
 899		u32_replace_knode(tp, tp_c, new);
 900		tcf_unbind_filter(tp, &n->res);
 901		call_rcu(&n->rcu, u32_delete_key_rcu);
 902		return 0;
 903	}
 904
 905	if (tb[TCA_U32_DIVISOR]) {
 906		unsigned int divisor = nla_get_u32(tb[TCA_U32_DIVISOR]);
 907
 908		if (--divisor > 0x100)
 909			return -EINVAL;
 910		if (TC_U32_KEY(handle))
 911			return -EINVAL;
 912		if (handle == 0) {
 913			handle = gen_new_htid(tp->data);
 914			if (handle == 0)
 915				return -ENOMEM;
 916		}
 917		ht = kzalloc(sizeof(*ht) + divisor*sizeof(void *), GFP_KERNEL);
 918		if (ht == NULL)
 919			return -ENOBUFS;
 920		ht->tp_c = tp_c;
 921		ht->refcnt = 1;
 922		ht->divisor = divisor;
 923		ht->handle = handle;
 924		ht->prio = tp->prio;
 925
 926		err = u32_replace_hw_hnode(tp, ht, flags);
 927		if (err) {
 928			kfree(ht);
 929			return err;
 930		}
 931
 932		RCU_INIT_POINTER(ht->next, tp_c->hlist);
 933		rcu_assign_pointer(tp_c->hlist, ht);
 934		*arg = (unsigned long)ht;
 935
 936		return 0;
 937	}
 938
 939	if (tb[TCA_U32_HASH]) {
 940		htid = nla_get_u32(tb[TCA_U32_HASH]);
 941		if (TC_U32_HTID(htid) == TC_U32_ROOT) {
 942			ht = rtnl_dereference(tp->root);
 943			htid = ht->handle;
 944		} else {
 945			ht = u32_lookup_ht(tp->data, TC_U32_HTID(htid));
 946			if (ht == NULL)
 947				return -EINVAL;
 948		}
 949	} else {
 950		ht = rtnl_dereference(tp->root);
 951		htid = ht->handle;
 952	}
 953
 954	if (ht->divisor < TC_U32_HASH(htid))
 955		return -EINVAL;
 956
 957	if (handle) {
 958		if (TC_U32_HTID(handle) && TC_U32_HTID(handle^htid))
 959			return -EINVAL;
 960		handle = htid | TC_U32_NODE(handle);
 961	} else
 962		handle = gen_new_kid(ht, htid);
 963
 964	if (tb[TCA_U32_SEL] == NULL)
 965		return -EINVAL;
 966
 967	s = nla_data(tb[TCA_U32_SEL]);
 968
 969	n = kzalloc(sizeof(*n) + s->nkeys*sizeof(struct tc_u32_key), GFP_KERNEL);
 970	if (n == NULL)
 971		return -ENOBUFS;
 972
 973#ifdef CONFIG_CLS_U32_PERF
 974	size = sizeof(struct tc_u32_pcnt) + s->nkeys * sizeof(u64);
 975	n->pf = __alloc_percpu(size, __alignof__(struct tc_u32_pcnt));
 976	if (!n->pf) {
 977		kfree(n);
 978		return -ENOBUFS;
 979	}
 980#endif
 981
 982	memcpy(&n->sel, s, sizeof(*s) + s->nkeys*sizeof(struct tc_u32_key));
 983	RCU_INIT_POINTER(n->ht_up, ht);
 984	n->handle = handle;
 985	n->fshift = s->hmask ? ffs(ntohl(s->hmask)) - 1 : 0;
 986	n->flags = flags;
 987	n->tp = tp;
 988
 989	err = tcf_exts_init(&n->exts, TCA_U32_ACT, TCA_U32_POLICE);
 990	if (err < 0)
 991		goto errout;
 992
 993#ifdef CONFIG_CLS_U32_MARK
 994	n->pcpu_success = alloc_percpu(u32);
 995	if (!n->pcpu_success) {
 996		err = -ENOMEM;
 997		goto errout;
 998	}
 999
1000	if (tb[TCA_U32_MARK]) {
1001		struct tc_u32_mark *mark;
1002
1003		mark = nla_data(tb[TCA_U32_MARK]);
1004		n->val = mark->val;
1005		n->mask = mark->mask;
1006	}
1007#endif
1008
1009	err = u32_set_parms(net, tp, base, ht, n, tb, tca[TCA_RATE], ovr);
1010	if (err == 0) {
1011		struct tc_u_knode __rcu **ins;
1012		struct tc_u_knode *pins;
 
 
1013
1014		err = u32_replace_hw_knode(tp, n, flags);
1015		if (err)
1016			goto errhw;
1017
1018		ins = &ht->ht[TC_U32_HASH(handle)];
1019		for (pins = rtnl_dereference(*ins); pins;
1020		     ins = &pins->next, pins = rtnl_dereference(*ins))
1021			if (TC_U32_NODE(handle) < TC_U32_NODE(pins->handle))
1022				break;
1023
1024		RCU_INIT_POINTER(n->next, pins);
1025		rcu_assign_pointer(*ins, n);
1026		*arg = (unsigned long)n;
1027		return 0;
1028	}
1029
1030errhw:
1031#ifdef CONFIG_CLS_U32_MARK
1032	free_percpu(n->pcpu_success);
1033#endif
1034
1035errout:
1036	tcf_exts_destroy(&n->exts);
1037#ifdef CONFIG_CLS_U32_PERF
1038	free_percpu(n->pf);
1039#endif
1040	kfree(n);
1041	return err;
1042}
1043
1044static void u32_walk(struct tcf_proto *tp, struct tcf_walker *arg)
1045{
1046	struct tc_u_common *tp_c = tp->data;
1047	struct tc_u_hnode *ht;
1048	struct tc_u_knode *n;
1049	unsigned int h;
1050
1051	if (arg->stop)
1052		return;
1053
1054	for (ht = rtnl_dereference(tp_c->hlist);
1055	     ht;
1056	     ht = rtnl_dereference(ht->next)) {
1057		if (ht->prio != tp->prio)
1058			continue;
1059		if (arg->count >= arg->skip) {
1060			if (arg->fn(tp, (unsigned long)ht, arg) < 0) {
1061				arg->stop = 1;
1062				return;
1063			}
1064		}
1065		arg->count++;
1066		for (h = 0; h <= ht->divisor; h++) {
1067			for (n = rtnl_dereference(ht->ht[h]);
1068			     n;
1069			     n = rtnl_dereference(n->next)) {
1070				if (arg->count < arg->skip) {
1071					arg->count++;
1072					continue;
1073				}
1074				if (arg->fn(tp, (unsigned long)n, arg) < 0) {
1075					arg->stop = 1;
1076					return;
1077				}
1078				arg->count++;
1079			}
1080		}
1081	}
1082}
1083
1084static int u32_dump(struct net *net, struct tcf_proto *tp, unsigned long fh,
1085		    struct sk_buff *skb, struct tcmsg *t)
1086{
1087	struct tc_u_knode *n = (struct tc_u_knode *)fh;
1088	struct tc_u_hnode *ht_up, *ht_down;
1089	struct nlattr *nest;
1090
1091	if (n == NULL)
1092		return skb->len;
1093
1094	t->tcm_handle = n->handle;
1095
1096	nest = nla_nest_start(skb, TCA_OPTIONS);
1097	if (nest == NULL)
1098		goto nla_put_failure;
1099
1100	if (TC_U32_KEY(n->handle) == 0) {
1101		struct tc_u_hnode *ht = (struct tc_u_hnode *)fh;
1102		u32 divisor = ht->divisor + 1;
1103
1104		if (nla_put_u32(skb, TCA_U32_DIVISOR, divisor))
1105			goto nla_put_failure;
1106	} else {
1107#ifdef CONFIG_CLS_U32_PERF
1108		struct tc_u32_pcnt *gpf;
1109		int cpu;
1110#endif
1111
1112		if (nla_put(skb, TCA_U32_SEL,
1113			    sizeof(n->sel) + n->sel.nkeys*sizeof(struct tc_u32_key),
1114			    &n->sel))
1115			goto nla_put_failure;
1116
1117		ht_up = rtnl_dereference(n->ht_up);
1118		if (ht_up) {
1119			u32 htid = n->handle & 0xFFFFF000;
1120			if (nla_put_u32(skb, TCA_U32_HASH, htid))
1121				goto nla_put_failure;
1122		}
1123		if (n->res.classid &&
1124		    nla_put_u32(skb, TCA_U32_CLASSID, n->res.classid))
1125			goto nla_put_failure;
1126
1127		ht_down = rtnl_dereference(n->ht_down);
1128		if (ht_down &&
1129		    nla_put_u32(skb, TCA_U32_LINK, ht_down->handle))
1130			goto nla_put_failure;
1131
1132		if (n->flags && nla_put_u32(skb, TCA_U32_FLAGS, n->flags))
 
 
1133			goto nla_put_failure;
1134
1135#ifdef CONFIG_CLS_U32_MARK
1136		if ((n->val || n->mask)) {
1137			struct tc_u32_mark mark = {.val = n->val,
1138						   .mask = n->mask,
1139						   .success = 0};
1140			int cpum;
1141
1142			for_each_possible_cpu(cpum) {
1143				__u32 cnt = *per_cpu_ptr(n->pcpu_success, cpum);
1144
1145				mark.success += cnt;
1146			}
1147
1148			if (nla_put(skb, TCA_U32_MARK, sizeof(mark), &mark))
1149				goto nla_put_failure;
1150		}
1151#endif
1152
1153		if (tcf_exts_dump(skb, &n->exts) < 0)
1154			goto nla_put_failure;
1155
1156#ifdef CONFIG_NET_CLS_IND
1157		if (n->ifindex) {
1158			struct net_device *dev;
1159			dev = __dev_get_by_index(net, n->ifindex);
1160			if (dev && nla_put_string(skb, TCA_U32_INDEV, dev->name))
1161				goto nla_put_failure;
1162		}
1163#endif
1164#ifdef CONFIG_CLS_U32_PERF
1165		gpf = kzalloc(sizeof(struct tc_u32_pcnt) +
1166			      n->sel.nkeys * sizeof(u64),
1167			      GFP_KERNEL);
1168		if (!gpf)
1169			goto nla_put_failure;
1170
1171		for_each_possible_cpu(cpu) {
1172			int i;
1173			struct tc_u32_pcnt *pf = per_cpu_ptr(n->pf, cpu);
1174
1175			gpf->rcnt += pf->rcnt;
1176			gpf->rhit += pf->rhit;
1177			for (i = 0; i < n->sel.nkeys; i++)
1178				gpf->kcnts[i] += pf->kcnts[i];
1179		}
1180
1181		if (nla_put_64bit(skb, TCA_U32_PCNT,
1182				  sizeof(struct tc_u32_pcnt) +
1183				  n->sel.nkeys * sizeof(u64),
1184				  gpf, TCA_U32_PAD)) {
1185			kfree(gpf);
1186			goto nla_put_failure;
1187		}
1188		kfree(gpf);
1189#endif
1190	}
1191
1192	nla_nest_end(skb, nest);
1193
1194	if (TC_U32_KEY(n->handle))
1195		if (tcf_exts_dump_stats(skb, &n->exts) < 0)
1196			goto nla_put_failure;
1197	return skb->len;
1198
1199nla_put_failure:
1200	nla_nest_cancel(skb, nest);
1201	return -1;
1202}
1203
1204static struct tcf_proto_ops cls_u32_ops __read_mostly = {
1205	.kind		=	"u32",
1206	.classify	=	u32_classify,
1207	.init		=	u32_init,
1208	.destroy	=	u32_destroy,
1209	.get		=	u32_get,
 
1210	.change		=	u32_change,
1211	.delete		=	u32_delete,
1212	.walk		=	u32_walk,
1213	.dump		=	u32_dump,
1214	.owner		=	THIS_MODULE,
1215};
1216
1217static int __init init_u32(void)
1218{
1219	pr_info("u32 classifier\n");
1220#ifdef CONFIG_CLS_U32_PERF
1221	pr_info("    Performance counters on\n");
1222#endif
1223#ifdef CONFIG_NET_CLS_IND
1224	pr_info("    input device check on\n");
1225#endif
1226#ifdef CONFIG_NET_CLS_ACT
1227	pr_info("    Actions configured\n");
1228#endif
1229	return register_tcf_proto_ops(&cls_u32_ops);
1230}
1231
1232static void __exit exit_u32(void)
1233{
1234	unregister_tcf_proto_ops(&cls_u32_ops);
1235}
1236
1237module_init(init_u32)
1238module_exit(exit_u32)
1239MODULE_LICENSE("GPL");