diff options
| -rw-r--r-- | include/linux/netfilter/xt_quota.h | 16 | ||||
| -rw-r--r-- | net/netfilter/Kconfig | 10 | ||||
| -rw-r--r-- | net/netfilter/Makefile | 1 | ||||
| -rw-r--r-- | net/netfilter/xt_quota.c | 96 |
4 files changed, 123 insertions, 0 deletions
diff --git a/include/linux/netfilter/xt_quota.h b/include/linux/netfilter/xt_quota.h new file mode 100644 index 000000000000..acd7fd77bbee --- /dev/null +++ b/include/linux/netfilter/xt_quota.h @@ -0,0 +1,16 @@ +#ifndef _XT_QUOTA_H +#define _XT_QUOTA_H + +enum xt_quota_flags { + XT_QUOTA_INVERT = 0x1, +}; +#define XT_QUOTA_MASK 0x1 + +struct xt_quota_info { + u_int32_t flags; + u_int32_t pad; + aligned_u64 quota; + struct xt_quota_info *master; +}; + +#endif /* _XT_QUOTA_H */ diff --git a/net/netfilter/Kconfig b/net/netfilter/Kconfig index e2893effdfaa..5543c7b74535 100644 --- a/net/netfilter/Kconfig +++ b/net/netfilter/Kconfig @@ -329,6 +329,16 @@ config NETFILTER_XT_MATCH_PKTTYPE To compile it as a module, choose M here. If unsure, say N. +config NETFILTER_XT_MATCH_QUOTA + tristate '"quota" match support' + depends on NETFILTER_XTABLES + help + This option adds a `quota' match, which allows to match on a + byte counter. + + If you want to compile it as a module, say M here and read + <file:Documentation/modules.txt>. If unsure, say `N'. + config NETFILTER_XT_MATCH_REALM tristate '"realm" match support' depends on NETFILTER_XTABLES diff --git a/net/netfilter/Makefile b/net/netfilter/Makefile index 95b7e416512d..4b6a6ea07373 100644 --- a/net/netfilter/Makefile +++ b/net/netfilter/Makefile @@ -44,6 +44,7 @@ obj-$(CONFIG_NETFILTER_XT_MATCH_MARK) += xt_mark.o obj-$(CONFIG_NETFILTER_XT_MATCH_MULTIPORT) += xt_multiport.o obj-$(CONFIG_NETFILTER_XT_MATCH_POLICY) += xt_policy.o obj-$(CONFIG_NETFILTER_XT_MATCH_PKTTYPE) += xt_pkttype.o +obj-$(CONFIG_NETFILTER_XT_MATCH_QUOTA) += xt_quota.o obj-$(CONFIG_NETFILTER_XT_MATCH_REALM) += xt_realm.o obj-$(CONFIG_NETFILTER_XT_MATCH_SCTP) += xt_sctp.o obj-$(CONFIG_NETFILTER_XT_MATCH_STATE) += xt_state.o diff --git a/net/netfilter/xt_quota.c b/net/netfilter/xt_quota.c new file mode 100644 index 000000000000..4cdba7469dc4 --- /dev/null +++ b/net/netfilter/xt_quota.c @@ -0,0 +1,96 @@ +/* + * netfilter module to enforce network quotas + * + * Sam Johnston <samj@samj.net> + */ +#include <linux/skbuff.h> +#include <linux/spinlock.h> + +#include <linux/netfilter/x_tables.h> +#include <linux/netfilter/xt_quota.h> + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Sam Johnston <samj@samj.net>"); + +static DEFINE_SPINLOCK(quota_lock); + +static int +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, int *hotdrop) +{ + struct xt_quota_info *q = ((struct xt_quota_info *)matchinfo)->master; + int ret = q->flags & XT_QUOTA_INVERT ? 1 : 0; + + spin_lock_bh("a_lock); + if (q->quota >= skb->len) { + q->quota -= skb->len; + ret ^= 1; + } else { + /* we do not allow even small packets from now on */ + q->quota = 0; + } + spin_unlock_bh("a_lock); + + return ret; +} + +static int +checkentry(const char *tablename, const void *entry, + const struct xt_match *match, void *matchinfo, + unsigned int matchsize, unsigned int hook_mask) +{ + struct xt_quota_info *q = (struct xt_quota_info *)matchinfo; + + if (q->flags & ~XT_QUOTA_MASK) + return 0; + /* For SMP, we only want to use one set of counters. */ + q->master = q; + return 1; +} + +static struct xt_match quota_match = { + .name = "quota", + .family = AF_INET, + .match = match, + .matchsize = sizeof(struct xt_quota_info), + .checkentry = checkentry, + .me = THIS_MODULE +}; + +static struct xt_match quota_match6 = { + .name = "quota", + .family = AF_INET6, + .match = match, + .matchsize = sizeof(struct xt_quota_info), + .checkentry = checkentry, + .me = THIS_MODULE +}; + +static int __init xt_quota_init(void) +{ + int ret; + + ret = xt_register_match("a_match); + if (ret) + goto err1; + ret = xt_register_match("a_match6); + if (ret) + goto err2; + return ret; + +err2: + xt_unregister_match("a_match); +err1: + return ret; +} + +static void __exit xt_quota_fini(void) +{ + xt_unregister_match("a_match6); + xt_unregister_match("a_match); +} + +module_init(xt_quota_init); +module_exit(xt_quota_fini); |