@@ -3,11 +3,24 @@
#include <uapi/linux/netfilter/nfnetlink_acct.h>
+struct nf_acct {
+ atomic64_t pkts;
+ atomic64_t bytes;
+ struct list_head head;
+ atomic_t refcnt;
+ char name[NFACCT_NAME_MAX];
+ struct rcu_head rcu_head;
+};
-struct nf_acct;
+enum nfnl_acct_udt_type {
+ NFNL_ACCT_UDT_PACKETS,
+ NFNL_ACCT_UDT_BYTES,
+};
struct nf_acct *nfnl_acct_find_get(const char *filter_name);
void nfnl_acct_put(struct nf_acct *acct);
-void nfnl_acct_update(const struct sk_buff *skb, struct nf_acct *nfacct);
+extern u64 nfnl_acct_update(const struct sk_buff *skb,
+ struct nf_acct *nfacct, int mode);
+void nfnl_quota_event(struct nf_acct *cur);
#endif /* _NFNL_ACCT_H */
@@ -20,6 +20,8 @@ enum nfnetlink_groups {
#define NFNLGRP_CONNTRACK_EXP_DESTROY NFNLGRP_CONNTRACK_EXP_DESTROY
NFNLGRP_NFTABLES,
#define NFNLGRP_NFTABLES NFNLGRP_NFTABLES
+ NFNLGRP_ACCT_QUOTA,
+#define NFNLGRP_ACCT_QUOTA NFNLGRP_ACCT_QUOTA
__NFNLGRP_MAX,
};
#define NFNLGRP_MAX (__NFNLGRP_MAX - 1)
@@ -19,6 +19,7 @@ enum nfnl_acct_type {
NFACCT_PKTS,
NFACCT_BYTES,
NFACCT_USE,
+ NFACCT_QUOTA,
__NFACCT_MAX
};
#define NFACCT_MAX (__NFACCT_MAX - 1)
@@ -3,11 +3,27 @@
#include <linux/netfilter/nfnetlink_acct.h>
+enum xt_quota_flags {
+ XT_NFACCT_QUOTA_PKTS = 1 << 0,
+ XT_NFACCT_QUOTA = 1 << 1,
+};
+
struct nf_acct;
+struct nf_acct_quota;
struct xt_nfacct_match_info {
char name[NFACCT_NAME_MAX];
- struct nf_acct *nfacct;
+ struct nf_acct *nfacct __aligned(8);
};
+struct xt_nfacct_match_info_v1 {
+ char name[NFACCT_NAME_MAX];
+ struct nf_acct *nfacct __aligned(8);
+
+ __u32 flags;
+ __aligned_u64 quota;
+
+ /* used internally by kernel */
+ struct nf_acct_quota *priv __aligned(8);
+};
#endif /* _XT_NFACCT_MATCH_H */
@@ -1108,7 +1108,8 @@ config NETFILTER_XT_MATCH_NFACCT
select NETFILTER_NETLINK_ACCT
help
This option allows you to use the extended accounting through
- nfnetlink_acct.
+ nfnetlink_acct. It is also possible to add quotas at the
+ packet and byte level.
To compile it as a module, choose M here. If unsure, say N.
@@ -29,15 +29,6 @@ MODULE_DESCRIPTION("nfacct: Extended Netfilter accounting infrastructure");
static LIST_HEAD(nfnl_acct_list);
-struct nf_acct {
- atomic64_t pkts;
- atomic64_t bytes;
- struct list_head head;
- atomic_t refcnt;
- char name[NFACCT_NAME_MAX];
- struct rcu_head rcu_head;
-};
-
static int
nfnl_acct_new(struct sock *nfnl, struct sk_buff *skb,
const struct nlmsghdr *nlh, const struct nlattr * const tb[])
@@ -92,7 +83,7 @@ nfnl_acct_new(struct sock *nfnl, struct sk_buff *skb,
return 0;
}
-static int
+int
nfnl_acct_fill_info(struct sk_buff *skb, u32 portid, u32 seq, u32 type,
int event, struct nf_acct *acct)
{
@@ -134,6 +125,7 @@ nla_put_failure:
nlmsg_cancel(skb, nlh);
return -1;
}
+EXPORT_SYMBOL_GPL(nfnl_acct_fill_info);
static int
nfnl_acct_dump(struct sk_buff *skb, struct netlink_callback *cb)
@@ -329,13 +321,41 @@ void nfnl_acct_put(struct nf_acct *acct)
}
EXPORT_SYMBOL_GPL(nfnl_acct_put);
-void nfnl_acct_update(const struct sk_buff *skb, struct nf_acct *nfacct)
+u64 nfnl_acct_update(const struct sk_buff *skb,
+ struct nf_acct *nfacct, int mode)
{
- atomic64_inc(&nfacct->pkts);
- atomic64_add(skb->len, &nfacct->bytes);
+ u64 pkts, bytes;
+
+ pkts = atomic64_inc_return(&nfacct->pkts);
+ bytes = atomic64_add_return(skb->len, &nfacct->bytes);
+
+ return (mode == NFNL_ACCT_UDT_PACKETS) ? pkts : bytes;
}
EXPORT_SYMBOL_GPL(nfnl_acct_update);
+void
+nfnl_quota_event(struct nf_acct *cur)
+{
+ int ret;
+ struct sk_buff *skb;
+
+ skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC);
+ if (skb == NULL)
+ return;
+
+ ret = nfnl_acct_fill_info(skb, 0, 0, NFACCT_QUOTA,
+ NFNL_MSG_ACCT_NEW, cur);
+
+ if (ret <= 0) {
+ kfree_skb(skb);
+ return;
+ }
+
+ netlink_broadcast(init_net.nfnl, skb, 0,
+ NFNLGRP_ACCT_QUOTA, GFP_ATOMIC);
+}
+EXPORT_SYMBOL_GPL(nfnl_quota_event);
+
static int __init nfnl_acct_init(void)
{
int ret;
@@ -9,8 +9,10 @@
#include <linux/module.h>
#include <linux/skbuff.h>
+#include <net/netlink.h>
#include <linux/netfilter/x_tables.h>
#include <linux/netfilter/nfnetlink_acct.h>
+#include <linux/netfilter/nfnetlink.h>
#include <linux/netfilter/xt_nfacct.h>
MODULE_AUTHOR("Pablo Neira Ayuso <pablo@netfilter.org>");
@@ -19,15 +21,62 @@ MODULE_LICENSE("GPL");
MODULE_ALIAS("ipt_nfacct");
MODULE_ALIAS("ip6t_nfacct");
+static LIST_HEAD(nfacct_list);
+static DEFINE_MUTEX(nfacct_list_mutex);
+
+struct nf_acct_quota {
+ char name[NFACCT_NAME_MAX];
+ int count;
+ u32 flags;
+ u64 quota;
+ struct list_head node;
+ atomic_t notified;
+};
+
static bool nfacct_mt(const struct sk_buff *skb, struct xt_action_param *par)
{
const struct xt_nfacct_match_info *info = par->targinfo;
+ u64 __always_unused val;
- nfnl_acct_update(skb, info->nfacct);
+ val = nfnl_acct_update(skb, info->nfacct, 0);
return true;
}
+static bool
+nfacct_mt_v1(const struct sk_buff *skb, struct xt_action_param *par)
+{
+ int mode;
+ u64 val;
+ const struct xt_nfacct_match_info_v1 *info = par->matchinfo;
+ struct nf_acct_quota *acct_quota = info->priv;
+ bool ret = true;
+
+ mode = (acct_quota->flags & XT_NFACCT_QUOTA_PKTS) ?
+ NFNL_ACCT_UDT_PACKETS : NFNL_ACCT_UDT_BYTES;
+
+ /* upgrade accounting stats */
+ val = nfnl_acct_update(skb, info->nfacct, mode);
+
+ /* no need to go further if we don't have a quota */
+ if (!(acct_quota->flags & XT_NFACCT_QUOTA))
+ return ret;
+
+ /* are we over the limit ? */
+ if (val <= info->quota) {
+ /* reset flag in case userspace cleared the counters */
+ atomic_set(&acct_quota->notified, 0);
+ ret = !ret;
+ }
+
+ if (val >= info->quota)
+ /* cmpxchg guarantees only one CPU can send a notification */
+ if (atomic_cmpxchg(&acct_quota->notified, 0, 1) == 0)
+ nfnl_quota_event(info->nfacct);
+
+ return ret;
+}
+
static int
nfacct_mt_checkentry(const struct xt_mtchk_param *par)
{
@@ -44,32 +93,140 @@ nfacct_mt_checkentry(const struct xt_mtchk_param *par)
return 0;
}
+static
+struct nf_acct_quota *nfacct_find_quota(char *name)
+{
+ struct nf_acct_quota *curr, *match = NULL;
+
+ mutex_lock(&nfacct_list_mutex);
+ list_for_each_entry(curr, &nfacct_list, node)
+ if (strncmp(curr->name, name, NFACCT_NAME_MAX) == 0) {
+ match = curr;
+ match->count++;
+ break;
+ }
+
+ mutex_unlock(&nfacct_list_mutex);
+
+ return match;
+}
+
+static struct nf_acct_quota *
+nfacct_create_quota(struct xt_nfacct_match_info_v1 *info)
+{
+ struct nf_acct_quota *acct_quota;
+
+ mutex_lock(&nfacct_list_mutex);
+
+ acct_quota = kmalloc(sizeof(struct nf_acct_quota), GFP_ATOMIC);
+
+ if (!acct_quota) {
+ mutex_unlock(&nfacct_list_mutex);
+ return NULL;
+ }
+
+ strncpy(acct_quota->name, info->name, NFACCT_NAME_MAX);
+ acct_quota->flags = info->flags;
+ acct_quota->quota = info->quota;
+ acct_quota->count = 1;
+ atomic_set(&acct_quota->notified, 0);
+ list_add_tail(&acct_quota->node, &nfacct_list);
+
+ mutex_unlock(&nfacct_list_mutex);
+
+ return acct_quota;
+}
+
+static int
+nfacct_mt_checkentry_v1(const struct xt_mtchk_param *par)
+{
+ struct xt_nfacct_match_info_v1 *info = par->matchinfo;
+ struct nf_acct *nfacct;
+ struct nf_acct_quota *acct_quota = NULL;
+
+ nfacct = nfnl_acct_find_get(info->name);
+ if (nfacct == NULL) {
+ pr_info("xt_nfacct: invalid accounting object `%s'\n",
+ info->name);
+ return -ENOENT;
+ }
+
+ info->nfacct = nfacct;
+
+ if (info->flags & XT_NFACCT_QUOTA) {
+ /* get quota object from list */
+ acct_quota = nfacct_find_quota(info->name);
+
+ /* object doesn't exist - create it */
+ if (acct_quota == NULL) {
+ acct_quota = nfacct_create_quota(info);
+ /* something went wrong - get out of here */
+ if (acct_quota == NULL) {
+ nfnl_acct_put(info->nfacct);
+ return -ENOMEM;
+ }
+ }
+ }
+
+ info->priv = acct_quota;
+
+ return 0;
+}
+
static void
nfacct_mt_destroy(const struct xt_mtdtor_param *par)
{
const struct xt_nfacct_match_info *info = par->matchinfo;
+ nfnl_acct_put(info->nfacct);
+}
+
+static void
+nfacct_mt_destroy_v1(const struct xt_mtdtor_param *par)
+{
+ const struct xt_nfacct_match_info_v1 *info = par->matchinfo;
+ struct nf_acct_quota *acct_quota = info->priv;
nfnl_acct_put(info->nfacct);
+
+ mutex_lock(&nfacct_list_mutex);
+ if (--acct_quota->count == 0) {
+ list_del(&acct_quota->node);
+ kfree(acct_quota);
+ }
+ mutex_unlock(&nfacct_list_mutex);
}
-static struct xt_match nfacct_mt_reg __read_mostly = {
- .name = "nfacct",
- .family = NFPROTO_UNSPEC,
- .checkentry = nfacct_mt_checkentry,
- .match = nfacct_mt,
- .destroy = nfacct_mt_destroy,
- .matchsize = sizeof(struct xt_nfacct_match_info),
- .me = THIS_MODULE,
+static struct xt_match nfacct_mt_reg[] __read_mostly = {
+ {
+ .name = "nfacct",
+ .family = NFPROTO_UNSPEC,
+ .checkentry = nfacct_mt_checkentry,
+ .match = nfacct_mt,
+ .destroy = nfacct_mt_destroy,
+ .matchsize = sizeof(struct xt_nfacct_match_info),
+ .me = THIS_MODULE,
+ },
+ {
+ .name = "nfacct",
+ .revision = 1,
+ .family = NFPROTO_UNSPEC,
+ .checkentry = nfacct_mt_checkentry_v1,
+ .match = nfacct_mt_v1,
+ .destroy = nfacct_mt_destroy_v1,
+ .matchsize = sizeof(struct xt_nfacct_match_info_v1),
+ .me = THIS_MODULE,
+ },
+
};
static int __init nfacct_mt_init(void)
{
- return xt_register_match(&nfacct_mt_reg);
+ return xt_register_matches(nfacct_mt_reg, ARRAY_SIZE(nfacct_mt_reg));
}
static void __exit nfacct_mt_exit(void)
{
- xt_unregister_match(&nfacct_mt_reg);
+ xt_unregister_matches(nfacct_mt_reg, ARRAY_SIZE(nfacct_mt_reg));
}
module_init(nfacct_mt_init);