// SPDX-License-Identifier: GPL-2.0-only
/*
* (C) 2007 Patrick McHardy <[email protected]>
*/
#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, struct xt_action_param *par)
{
const struct xt_rateest_match_info *info = par->matchinfo;
struct gnet_stats_rate_est64 sample = {0};
u_int32_t bps1, bps2, pps1, pps2;
bool ret = true;
gen_estimator_read(&info->est1->rate_est, &sample);
if (info->flags & XT_RATEEST_MATCH_DELTA) {
bps1 = info->bps1 >= sample.bps ? info->bps1 - sample.bps : 0;
pps1 = info->pps1 >= sample.pps ? info->pps1 - sample.pps : 0;
} else {
bps1 = sample.bps;
pps1 = sample.pps;
}
if (info->flags & XT_RATEEST_MATCH_ABS) {
bps2 = info->bps2;
pps2 = info->pps2;
} else {
gen_estimator_read(&info->est2->rate_est, &sample);
if (info->flags & XT_RATEEST_MATCH_DELTA) {
bps2 = info->bps2 >= sample.bps ? info->bps2 - sample.bps : 0;
pps2 = info->pps2 >= sample.pps ? info->pps2 - sample.pps : 0;
} else {
bps2 = sample.bps;
pps2 = sample.pps;
}
}
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 &= pps1 == pps2;
break;
}
ret ^= info->flags & XT_RATEEST_MATCH_INVERT ? true : false;
return ret;
}
static int xt_rateest_mt_checkentry(const struct xt_mtchk_param *par)
{
struct xt_rateest_match_info *info = par->matchinfo;
struct xt_rateest *est1, *est2;
int ret = -EINVAL;
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;
}
ret = -ENOENT;
est1 = xt_rateest_lookup(par->net, info->name1);
if (!est1)
goto err1;
est2 = NULL;
if (info->flags & XT_RATEEST_MATCH_REL) {
est2 = xt_rateest_lookup(par->net, info->name2);
if (!est2)
goto err2;
}
info->est1 = est1;
info->est2 = est2;
return 0;
err2:
xt_rateest_put(par->net, est1);
err1:
return ret;
}
static void xt_rateest_mt_destroy(const struct xt_mtdtor_param *par)
{
struct xt_rateest_match_info *info = par->matchinfo;
xt_rateest_put(par->net, info->est1);
if (info->est2)
xt_rateest_put(par->net, 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),
.usersize = offsetof(struct xt_rateest_match_info, est1),
.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 <[email protected]>");
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);