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Diffstat (limited to 'net/netfilter/xt_limit.c')
-rw-r--r--net/netfilter/xt_limit.c116
1 files changed, 58 insertions, 58 deletions
diff --git a/net/netfilter/xt_limit.c b/net/netfilter/xt_limit.c
index aad9ab8d204..bef85059655 100644
--- a/net/netfilter/xt_limit.c
+++ b/net/netfilter/xt_limit.c
@@ -1,11 +1,14 @@
/* (C) 1999 Jérôme de Vivie <devivie@info.enserb.u-bordeaux.fr>
* (C) 1999 Hervé Eychenne <eychenne@info.enserb.u-bordeaux.fr>
+ * (C) 2006-2012 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.
*/
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+#include <linux/slab.h>
#include <linux/module.h>
#include <linux/skbuff.h>
#include <linux/spinlock.h>
@@ -14,6 +17,11 @@
#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("Xtables: rate-limit match");
@@ -58,23 +66,20 @@ static DEFINE_SPINLOCK(limit_lock);
#define CREDITS_PER_JIFFY POW2_BELOW32(MAX_CPJ)
static bool
-limit_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)
+limit_mt(const struct sk_buff *skb, struct xt_action_param *par)
{
- struct xt_rateinfo *r =
- ((const 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;
}
@@ -84,8 +89,7 @@ limit_mt(const struct sk_buff *skb, const struct net_device *in,
}
/* Precision saver. */
-static u_int32_t
-user2credits(u_int32_t user)
+static u32 user2credits(u32 user)
{
/* If multiplying would overflow... */
if (user > 0xFFFFFFFF / (HZ*CREDITS_PER_JIFFY))
@@ -95,32 +99,41 @@ user2credits(u_int32_t user)
return (user * HZ * CREDITS_PER_JIFFY) / XT_LIMIT_SCALE;
}
-static bool
-limit_mt_check(const char *tablename, const void *inf,
- const struct xt_match *match, void *matchinfo,
- unsigned int hook_mask)
+static int 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 false;
+ pr_info("Overflow, try lower: %u/%u\n",
+ r->avg, r->burst);
+ return -ERANGE;
}
- /* For SMP, we only want to use one set of counters. */
- r->master = r;
+ priv = kmalloc(sizeof(*priv), GFP_KERNEL);
+ if (priv == NULL)
+ return -ENOMEM;
+
+ /* For SMP, we only want to use one set of state. */
+ r->master = priv;
+ /* User avg in seconds * XT_LIMIT_SCALE: convert to jiffies *
+ 128. */
+ priv->prev = jiffies;
+ priv->credit = user2credits(r->avg * r->burst); /* Credits full. */
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. */
- r->credit_cap = user2credits(r->avg * r->burst); /* Credits full. */
+ r->credit_cap = priv->credit; /* Credits full. */
r->cost = user2credits(r->avg);
}
- return true;
+ return 0;
+}
+
+static void limit_mt_destroy(const struct xt_mtdtor_param *par)
+{
+ const struct xt_rateinfo *info = par->matchinfo;
+
+ kfree(info->master);
}
#ifdef CONFIG_COMPAT
@@ -137,7 +150,7 @@ struct compat_xt_rateinfo {
/* 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 limit_mt_compat_from_user(void *dst, void *src)
+static void limit_mt_compat_from_user(void *dst, const void *src)
{
const struct compat_xt_rateinfo *cm = src;
struct xt_rateinfo m = {
@@ -151,7 +164,7 @@ static void limit_mt_compat_from_user(void *dst, void *src)
memcpy(dst, &m, sizeof(m));
}
-static int limit_mt_compat_to_user(void __user *dst, void *src)
+static int limit_mt_compat_to_user(void __user *dst, const void *src)
{
const struct xt_rateinfo *m = src;
struct compat_xt_rateinfo cm = {
@@ -167,43 +180,30 @@ static int limit_mt_compat_to_user(void __user *dst, void *src)
}
#endif /* CONFIG_COMPAT */
-static struct xt_match limit_mt_reg[] __read_mostly = {
- {
- .name = "limit",
- .family = AF_INET,
- .checkentry = limit_mt_check,
- .match = limit_mt,
- .matchsize = sizeof(struct xt_rateinfo),
-#ifdef CONFIG_COMPAT
- .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 = limit_mt_check,
- .match = limit_mt,
- .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 = limit_mt_compat_from_user,
- .compat_to_user = limit_mt_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,
- },
+ .me = THIS_MODULE,
};
static int __init limit_mt_init(void)
{
- return xt_register_matches(limit_mt_reg, ARRAY_SIZE(limit_mt_reg));
+ return xt_register_match(&limit_mt_reg);
}
static void __exit limit_mt_exit(void)
{
- xt_unregister_matches(limit_mt_reg, ARRAY_SIZE(limit_mt_reg));
+ xt_unregister_match(&limit_mt_reg);
}
module_init(limit_mt_init);
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2025-11-10 10:23:48 +0000