blob: fdb86a515146107da927761efbf6ed1567707514 [file] [log] [blame]
/*
* (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 = (void *)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 = (void *)matchinfo;
xt_rateest_put(info->est1);
if (info->est2)
xt_rateest_put(info->est2);
}
static struct xt_match xt_rateest_match[] __read_mostly = {
{
.family = AF_INET,
.name = "rateest",
.match = xt_rateest_mt,
.checkentry = xt_rateest_mt_checkentry,
.destroy = xt_rateest_mt_destroy,
.matchsize = sizeof(struct xt_rateest_match_info),
.me = THIS_MODULE,
},
{
.family = AF_INET6,
.name = "rateest",
.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_matches(xt_rateest_match,
ARRAY_SIZE(xt_rateest_match));
}
static void __exit xt_rateest_mt_fini(void)
{
xt_unregister_matches(xt_rateest_match, ARRAY_SIZE(xt_rateest_match));
}
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);