[deliverable/linux.git] / net / netfilter / xt_rateest.c

/*
 * (C) 2007 Patrick McHardy <kaber@trash.net>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */
#include <linux/module.h>
#include <linux/skbuff.h>
#include <linux/gen_stats.h>

#include <linux/netfilter/x_tables.h>
#include <linux/netfilter/xt_rateest.h>
#include <net/netfilter/xt_rateest.h>


static bool xt_rateest_mt(const struct sk_buff *skb,
			  const struct net_device *in,
			  const struct net_device *out,
			  const struct xt_match *match,
			  const void *matchinfo,
			  int offset,
			  unsigned int protoff,
			  bool *hotdrop)
{
	const struct xt_rateest_match_info *info = matchinfo;
	struct gnet_stats_rate_est *r;
	u_int32_t bps1, bps2, pps1, pps2;
	bool ret = true;

	spin_lock_bh(&info->est1->lock);
	r = &info->est1->rstats;
	if (info->flags & XT_RATEEST_MATCH_DELTA) {
		bps1 = info->bps1 >= r->bps ? info->bps1 - r->bps : 0;
		pps1 = info->pps1 >= r->pps ? info->pps1 - r->pps : 0;
	} else {
		bps1 = r->bps;
		pps1 = r->pps;
	}
	spin_unlock_bh(&info->est1->lock);

	if (info->flags & XT_RATEEST_MATCH_ABS) {
		bps2 = info->bps2;
		pps2 = info->pps2;
	} else {
		spin_lock_bh(&info->est2->lock);
		r = &info->est2->rstats;
		if (info->flags & XT_RATEEST_MATCH_DELTA) {
			bps2 = info->bps2 >= r->bps ? info->bps2 - r->bps : 0;
			pps2 = info->pps2 >= r->pps ? info->pps2 - r->pps : 0;
		} else {
			bps2 = r->bps;
			pps2 = r->pps;
		}
		spin_unlock_bh(&info->est2->lock);
	}

	switch (info->mode) {
	case XT_RATEEST_MATCH_LT:
		if (info->flags & XT_RATEEST_MATCH_BPS)
			ret &= bps1 < bps2;
		if (info->flags & XT_RATEEST_MATCH_PPS)
			ret &= pps1 < pps2;
		break;
	case XT_RATEEST_MATCH_GT:
		if (info->flags & XT_RATEEST_MATCH_BPS)
			ret &= bps1 > bps2;
		if (info->flags & XT_RATEEST_MATCH_PPS)
			ret &= pps1 > pps2;
		break;
	case XT_RATEEST_MATCH_EQ:
		if (info->flags & XT_RATEEST_MATCH_BPS)
			ret &= bps1 == bps2;
		if (info->flags & XT_RATEEST_MATCH_PPS)
			ret &= pps2 == pps2;
		break;
	}

	ret ^= info->flags & XT_RATEEST_MATCH_INVERT ? true : false;
	return ret;
}

static bool xt_rateest_mt_checkentry(const char *tablename,
				     const void *ip,
				     const struct xt_match *match,
				     void *matchinfo,
				     unsigned int hook_mask)
{
	struct xt_rateest_match_info *info = matchinfo;
	struct xt_rateest *est1, *est2;

	if (hweight32(info->flags & (XT_RATEEST_MATCH_ABS |
				     XT_RATEEST_MATCH_REL)) != 1)
		goto err1;

	if (!(info->flags & (XT_RATEEST_MATCH_BPS | XT_RATEEST_MATCH_PPS)))
		goto err1;

	switch (info->mode) {
	case XT_RATEEST_MATCH_EQ:
	case XT_RATEEST_MATCH_LT:
	case XT_RATEEST_MATCH_GT:
		break;
	default:
		goto err1;
	}

	est1 = xt_rateest_lookup(info->name1);
	if (!est1)
		goto err1;

	if (info->flags & XT_RATEEST_MATCH_REL) {
		est2 = xt_rateest_lookup(info->name2);
		if (!est2)
			goto err2;
	} else
		est2 = NULL;


	info->est1 = est1;
	info->est2 = est2;
	return true;

err2:
	xt_rateest_put(est1);
err1:
	return false;
}

static void xt_rateest_mt_destroy(const struct xt_match *match,
				  void *matchinfo)
{
	struct xt_rateest_match_info *info = matchinfo;

	xt_rateest_put(info->est1);
	if (info->est2)
		xt_rateest_put(info->est2);
}

static struct xt_match xt_rateest_mt_reg __read_mostly = {
	.name       = "rateest",
	.revision   = 0,
	.family     = NFPROTO_UNSPEC,
	.match      = xt_rateest_mt,
	.checkentry = xt_rateest_mt_checkentry,
	.destroy    = xt_rateest_mt_destroy,
	.matchsize  = sizeof(struct xt_rateest_match_info),
	.me         = THIS_MODULE,
};

static int __init xt_rateest_mt_init(void)
{
	return xt_register_match(&xt_rateest_mt_reg);
}

static void __exit xt_rateest_mt_fini(void)
{
	xt_unregister_match(&xt_rateest_mt_reg);
}

MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("xtables rate estimator match");
MODULE_ALIAS("ipt_rateest");
MODULE_ALIAS("ip6t_rateest");
module_init(xt_rateest_mt_init);
module_exit(xt_rateest_mt_fini);
Commit	Line	Data
50c164a8 PM	1	/*
	2	* (C) 2007 Patrick McHardy <kaber@trash.net>
	3	*
	4	* This program is free software; you can redistribute it and/or modify
	5	* it under the terms of the GNU General Public License version 2 as
	6	* published by the Free Software Foundation.
	7	*/
	8	#include <linux/module.h>
	9	#include <linux/skbuff.h>
	10	#include <linux/gen_stats.h>
	11
	12	#include <linux/netfilter/x_tables.h>
	13	#include <linux/netfilter/xt_rateest.h>
	14	#include <net/netfilter/xt_rateest.h>
	15
	16
	17	static bool xt_rateest_mt(const struct sk_buff *skb,
	18	const struct net_device *in,
	19	const struct net_device *out,
	20	const struct xt_match *match,
	21	const void *matchinfo,
	22	int offset,
	23	unsigned int protoff,
	24	bool *hotdrop)
	25	{
	26	const struct xt_rateest_match_info *info = matchinfo;
	27	struct gnet_stats_rate_est *r;
	28	u_int32_t bps1, bps2, pps1, pps2;
	29	bool ret = true;
	30
	31	spin_lock_bh(&info->est1->lock);
	32	r = &info->est1->rstats;
	33	if (info->flags & XT_RATEEST_MATCH_DELTA) {
	34	bps1 = info->bps1 >= r->bps ? info->bps1 - r->bps : 0;
	35	pps1 = info->pps1 >= r->pps ? info->pps1 - r->pps : 0;
	36	} else {
	37	bps1 = r->bps;
	38	pps1 = r->pps;
	39	}
	40	spin_unlock_bh(&info->est1->lock);
	41
	42	if (info->flags & XT_RATEEST_MATCH_ABS) {
	43	bps2 = info->bps2;
	44	pps2 = info->pps2;
	45	} else {
	46	spin_lock_bh(&info->est2->lock);
	47	r = &info->est2->rstats;
	48	if (info->flags & XT_RATEEST_MATCH_DELTA) {
	49	bps2 = info->bps2 >= r->bps ? info->bps2 - r->bps : 0;
	50	pps2 = info->pps2 >= r->pps ? info->pps2 - r->pps : 0;
	51	} else {
	52	bps2 = r->bps;
	53	pps2 = r->pps;
	54	}
	55	spin_unlock_bh(&info->est2->lock);
	56	}
	57
	58	switch (info->mode) {
	59	case XT_RATEEST_MATCH_LT:
	60	if (info->flags & XT_RATEEST_MATCH_BPS)
	61	ret &= bps1 < bps2;
	62	if (info->flags & XT_RATEEST_MATCH_PPS)
	63	ret &= pps1 < pps2;
	64	break;
65	case XT_RATEEST_MATCH_GT:
66	if (info->flags & XT_RATEEST_MATCH_BPS)
67	ret &= bps1 > bps2;
68	if (info->flags & XT_RATEEST_MATCH_PPS)
69	ret &= pps1 > pps2;
70	break;
71	case XT_RATEEST_MATCH_EQ:
72	if (info->flags & XT_RATEEST_MATCH_BPS)
73	ret &= bps1 == bps2;
74	if (info->flags & XT_RATEEST_MATCH_PPS)
75	ret &= pps2 == pps2;
76	break;
77	}
78
79	ret ^= info->flags & XT_RATEEST_MATCH_INVERT ? true : false;
80	return ret;
81	}
82
83	static bool xt_rateest_mt_checkentry(const char *tablename,
84	const void *ip,
85	const struct xt_match *match,
86	void *matchinfo,
87	unsigned int hook_mask)
88	{
3cf93c96	89	struct xt_rateest_match_info *info = matchinfo;
50c164a8 PM	90	struct xt_rateest est1, est2;
	91
	92	if (hweight32(info->flags & (XT_RATEEST_MATCH_ABS \|
	93	XT_RATEEST_MATCH_REL)) != 1)
	94	goto err1;
	95
	96	if (!(info->flags & (XT_RATEEST_MATCH_BPS \| XT_RATEEST_MATCH_PPS)))
	97	goto err1;
	98
	99	switch (info->mode) {
	100	case XT_RATEEST_MATCH_EQ:
	101	case XT_RATEEST_MATCH_LT:
	102	case XT_RATEEST_MATCH_GT:
	103	break;
	104	default:
	105	goto err1;
	106	}
	107
	108	est1 = xt_rateest_lookup(info->name1);
	109	if (!est1)
	110	goto err1;
	111
	112	if (info->flags & XT_RATEEST_MATCH_REL) {
	113	est2 = xt_rateest_lookup(info->name2);
	114	if (!est2)
	115	goto err2;
	116	} else
	117	est2 = NULL;
	118
	119
	120	info->est1 = est1;
	121	info->est2 = est2;
	122	return true;
	123
	124	err2:
	125	xt_rateest_put(est1);
	126	err1:
	127	return false;
	128	}
	129
	130	static void xt_rateest_mt_destroy(const struct xt_match *match,
	131	void *matchinfo)
	132	{
3cf93c96	133	struct xt_rateest_match_info *info = matchinfo;
50c164a8 PM	134
	135	xt_rateest_put(info->est1);
	136	if (info->est2)
	137	xt_rateest_put(info->est2);
	138	}
	139
55b69e91 JE	140	static struct xt_match xt_rateest_mt_reg __read_mostly = {
	141	.name = "rateest",
	142	.revision = 0,
	143	.family = NFPROTO_UNSPEC,
	144	.match = xt_rateest_mt,
	145	.checkentry = xt_rateest_mt_checkentry,
	146	.destroy = xt_rateest_mt_destroy,
	147	.matchsize = sizeof(struct xt_rateest_match_info),
	148	.me = THIS_MODULE,
50c164a8 PM	149	};
	150
	151	static int __init xt_rateest_mt_init(void)
	152	{
55b69e91	153	return xt_register_match(&xt_rateest_mt_reg);
50c164a8 PM	154	}
	155
	156	static void __exit xt_rateest_mt_fini(void)
	157	{
55b69e91	158	xt_unregister_match(&xt_rateest_mt_reg);
50c164a8 PM	159	}
	160
	161	MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
	162	MODULE_LICENSE("GPL");
	163	MODULE_DESCRIPTION("xtables rate estimator match");
	164	MODULE_ALIAS("ipt_rateest");
	165	MODULE_ALIAS("ip6t_rateest");
	166	module_init(xt_rateest_mt_init);
	167	module_exit(xt_rateest_mt_fini);