diff options
Diffstat (limited to 'net/netfilter/xt_statistic.c')
| -rw-r--r-- | net/netfilter/xt_statistic.c | 86 |
1 files changed, 43 insertions, 43 deletions
diff --git a/net/netfilter/xt_statistic.c b/net/netfilter/xt_statistic.c index 43133080da7..11de55e7a86 100644 --- a/net/netfilter/xt_statistic.c +++ b/net/netfilter/xt_statistic.c @@ -12,9 +12,15 @@ #include <linux/spinlock.h> #include <linux/skbuff.h> #include <linux/net.h> +#include <linux/slab.h> #include <linux/netfilter/xt_statistic.h> #include <linux/netfilter/x_tables.h> +#include <linux/module.h> + +struct xt_statistic_priv { + atomic_t count; +} ____cacheline_aligned_in_smp; MODULE_LICENSE("GPL"); MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>"); @@ -22,79 +28,73 @@ MODULE_DESCRIPTION("Xtables: statistics-based matching (\"Nth\", random)"); MODULE_ALIAS("ipt_statistic"); MODULE_ALIAS("ip6t_statistic"); -static DEFINE_SPINLOCK(nth_lock); - static bool -statistic_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) +statistic_mt(const struct sk_buff *skb, struct xt_action_param *par) { - struct xt_statistic_info *info = (struct xt_statistic_info *)matchinfo; + const struct xt_statistic_info *info = par->matchinfo; bool ret = info->flags & XT_STATISTIC_INVERT; + int nval, oval; switch (info->mode) { case XT_STATISTIC_MODE_RANDOM: - if ((net_random() & 0x7FFFFFFF) < info->u.random.probability) + if ((prandom_u32() & 0x7FFFFFFF) < info->u.random.probability) ret = !ret; break; case XT_STATISTIC_MODE_NTH: - info = info->master; - spin_lock_bh(&nth_lock); - if (info->u.nth.count++ == info->u.nth.every) { - info->u.nth.count = 0; + do { + oval = atomic_read(&info->master->count); + nval = (oval == info->u.nth.every) ? 0 : oval + 1; + } while (atomic_cmpxchg(&info->master->count, oval, nval) != oval); + if (nval == 0) ret = !ret; - } - spin_unlock_bh(&nth_lock); break; } return ret; } -static bool -statistic_mt_check(const char *tablename, const void *entry, - const struct xt_match *match, void *matchinfo, - unsigned int hook_mask) +static int statistic_mt_check(const struct xt_mtchk_param *par) { - struct xt_statistic_info *info = matchinfo; + struct xt_statistic_info *info = par->matchinfo; if (info->mode > XT_STATISTIC_MODE_MAX || info->flags & ~XT_STATISTIC_MASK) - return false; - info->master = info; - return true; + return -EINVAL; + + info->master = kzalloc(sizeof(*info->master), GFP_KERNEL); + if (info->master == NULL) + return -ENOMEM; + atomic_set(&info->master->count, info->u.nth.count); + + return 0; +} + +static void statistic_mt_destroy(const struct xt_mtdtor_param *par) +{ + const struct xt_statistic_info *info = par->matchinfo; + + kfree(info->master); } -static struct xt_match statistic_mt_reg[] __read_mostly = { - { - .name = "statistic", - .family = AF_INET, - .checkentry = statistic_mt_check, - .match = statistic_mt, - .matchsize = sizeof(struct xt_statistic_info), - .me = THIS_MODULE, - }, - { - .name = "statistic", - .family = AF_INET6, - .checkentry = statistic_mt_check, - .match = statistic_mt, - .matchsize = sizeof(struct xt_statistic_info), - .me = THIS_MODULE, - }, +static struct xt_match xt_statistic_mt_reg __read_mostly = { + .name = "statistic", + .revision = 0, + .family = NFPROTO_UNSPEC, + .match = statistic_mt, + .checkentry = statistic_mt_check, + .destroy = statistic_mt_destroy, + .matchsize = sizeof(struct xt_statistic_info), + .me = THIS_MODULE, }; static int __init statistic_mt_init(void) { - return xt_register_matches(statistic_mt_reg, - ARRAY_SIZE(statistic_mt_reg)); + return xt_register_match(&xt_statistic_mt_reg); } static void __exit statistic_mt_exit(void) { - xt_unregister_matches(statistic_mt_reg, - ARRAY_SIZE(statistic_mt_reg)); + xt_unregister_match(&xt_statistic_mt_reg); } module_init(statistic_mt_init); |
