-/* (C) 1999 Jérôme de Vivie <devivie@info.enserb.u-bordeaux.fr>
- * (C) 1999 Hervé Eychenne <eychenne@info.enserb.u-bordeaux.fr>
+/* (C) 1999 Jérôme de Vivie <devivie@info.enserb.u-bordeaux.fr>
+ * (C) 1999 Hervé Eychenne <eychenne@info.enserb.u-bordeaux.fr>
*
* 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
#include <linux/netfilter/x_tables.h>
#include <linux/netfilter/xt_limit.h>
+struct xt_limit_priv {
+ unsigned long prev;
+ uint32_t credit;
+};
+
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Herve Eychenne <rv@wallfire.org>");
-MODULE_DESCRIPTION("iptables rate limit match");
+MODULE_DESCRIPTION("Xtables: rate-limit match");
MODULE_ALIAS("ipt_limit");
MODULE_ALIAS("ip6t_limit");
#define CREDITS_PER_JIFFY POW2_BELOW32(MAX_CPJ)
static bool
-ipt_limit_match(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)
+limit_mt(const struct sk_buff *skb, const struct xt_match_param *par)
{
- struct xt_rateinfo *r = ((struct xt_rateinfo *)matchinfo)->master;
+ const struct xt_rateinfo *r = par->matchinfo;
+ struct xt_limit_priv *priv = r->master;
unsigned long now = jiffies;
spin_lock_bh(&limit_lock);
- r->credit += (now - xchg(&r->prev, now)) * CREDITS_PER_JIFFY;
- if (r->credit > r->credit_cap)
- r->credit = r->credit_cap;
+ priv->credit += (now - xchg(&priv->prev, now)) * CREDITS_PER_JIFFY;
+ if (priv->credit > r->credit_cap)
+ priv->credit = r->credit_cap;
- if (r->credit >= r->cost) {
+ if (priv->credit >= r->cost) {
/* We're not limited. */
- r->credit -= r->cost;
+ priv->credit -= r->cost;
spin_unlock_bh(&limit_lock);
return true;
}
return (user * HZ * CREDITS_PER_JIFFY) / XT_LIMIT_SCALE;
}
-static int
-ipt_limit_checkentry(const char *tablename,
- const void *inf,
- const struct xt_match *match,
- void *matchinfo,
- unsigned int hook_mask)
+static bool limit_mt_check(const struct xt_mtchk_param *par)
{
- struct xt_rateinfo *r = matchinfo;
+ struct xt_rateinfo *r = par->matchinfo;
+ struct xt_limit_priv *priv;
/* Check for overflow. */
if (r->burst == 0
|| user2credits(r->avg * r->burst) < user2credits(r->avg)) {
printk("Overflow in xt_limit, try lower: %u/%u\n",
r->avg, r->burst);
- return 0;
+ return false;
}
- /* For SMP, we only want to use one set of counters. */
- r->master = r;
+ priv = kmalloc(sizeof(*priv), GFP_KERNEL);
+ if (priv == NULL)
+ return false;
+
+ /* For SMP, we only want to use one set of state. */
+ r->master = priv;
if (r->cost == 0) {
/* User avg in seconds * XT_LIMIT_SCALE: convert to jiffies *
128. */
- r->prev = jiffies;
- r->credit = user2credits(r->avg * r->burst); /* Credits full. */
+ priv->prev = jiffies;
+ priv->credit = user2credits(r->avg * r->burst); /* Credits full. */
r->credit_cap = user2credits(r->avg * r->burst); /* Credits full. */
r->cost = user2credits(r->avg);
}
- return 1;
+ return true;
+}
+
+static void limit_mt_destroy(const struct xt_mtdtor_param *par)
+{
+ const struct xt_rateinfo *info = par->matchinfo;
+
+ kfree(info->master);
}
#ifdef CONFIG_COMPAT
/* To keep the full "prev" timestamp, the upper 32 bits are stored in the
* master pointer, which does not need to be preserved. */
-static void compat_from_user(void *dst, void *src)
+static void limit_mt_compat_from_user(void *dst, void *src)
{
- struct compat_xt_rateinfo *cm = src;
+ const struct compat_xt_rateinfo *cm = src;
struct xt_rateinfo m = {
.avg = cm->avg,
.burst = cm->burst,
memcpy(dst, &m, sizeof(m));
}
-static int compat_to_user(void __user *dst, void *src)
+static int limit_mt_compat_to_user(void __user *dst, void *src)
{
- struct xt_rateinfo *m = src;
+ const struct xt_rateinfo *m = src;
struct compat_xt_rateinfo cm = {
.avg = m->avg,
.burst = m->burst,
}
#endif /* CONFIG_COMPAT */
-static struct xt_match xt_limit_match[] = {
- {
- .name = "limit",
- .family = AF_INET,
- .checkentry = ipt_limit_checkentry,
- .match = ipt_limit_match,
- .matchsize = sizeof(struct xt_rateinfo),
+static struct xt_match limit_mt_reg __read_mostly = {
+ .name = "limit",
+ .revision = 0,
+ .family = NFPROTO_UNSPEC,
+ .match = limit_mt,
+ .checkentry = limit_mt_check,
+ .destroy = limit_mt_destroy,
+ .matchsize = sizeof(struct xt_rateinfo),
#ifdef CONFIG_COMPAT
- .compatsize = sizeof(struct compat_xt_rateinfo),
- .compat_from_user = compat_from_user,
- .compat_to_user = compat_to_user,
+ .compatsize = sizeof(struct compat_xt_rateinfo),
+ .compat_from_user = limit_mt_compat_from_user,
+ .compat_to_user = limit_mt_compat_to_user,
#endif
- .me = THIS_MODULE,
- },
- {
- .name = "limit",
- .family = AF_INET6,
- .checkentry = ipt_limit_checkentry,
- .match = ipt_limit_match,
- .matchsize = sizeof(struct xt_rateinfo),
- .me = THIS_MODULE,
- },
+ .me = THIS_MODULE,
};
-static int __init xt_limit_init(void)
+static int __init limit_mt_init(void)
{
- return xt_register_matches(xt_limit_match, ARRAY_SIZE(xt_limit_match));
+ return xt_register_match(&limit_mt_reg);
}
-static void __exit xt_limit_fini(void)
+static void __exit limit_mt_exit(void)
{
- xt_unregister_matches(xt_limit_match, ARRAY_SIZE(xt_limit_match));
+ xt_unregister_match(&limit_mt_reg);
}
-module_init(xt_limit_init);
-module_exit(xt_limit_fini);
+module_init(limit_mt_init);
+module_exit(limit_mt_exit);
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff