netfilter: nf_ct_ext: add timeout extension

This patch adds the timeout extension, which allows you to attach
specific timeout policies to flows.

This extension is only used by the template conntrack.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

2 files changed, 82 insertions, 0 deletions

diff --git a/include/net/netfilter/nf_conntrack_extend.h b/include/net/netfilter/nf_conntrack_extend.h
index 2dcf31703ac..96755c3798a 100644
--- a/include/net/netfilter/nf_conntrack_extend.h
+++ b/include/net/netfilter/nf_conntrack_extend.h
@@ -20,6 +20,9 @@ enum nf_ct_ext_id {
 #ifdef CONFIG_NF_CONNTRACK_TIMESTAMP
 	NF_CT_EXT_TSTAMP,
 #endif
+#ifdef CONFIG_NF_CONNTRACK_TIMEOUT
+	NF_CT_EXT_TIMEOUT,
+#endif
 	NF_CT_EXT_NUM,
 };
 
@@ -29,6 +32,7 @@ enum nf_ct_ext_id {
 #define NF_CT_EXT_ECACHE_TYPE struct nf_conntrack_ecache
 #define NF_CT_EXT_ZONE_TYPE struct nf_conntrack_zone
 #define NF_CT_EXT_TSTAMP_TYPE struct nf_conn_tstamp
+#define NF_CT_EXT_TIMEOUT_TYPE struct nf_conn_timeout
 
 /* Extensions: optional stuff which isn't permanently in struct. */
 struct nf_ct_ext {
diff --git a/include/net/netfilter/nf_conntrack_timeout.h b/include/net/netfilter/nf_conntrack_timeout.h
new file mode 100644
index 00000000000..0e04db4a086
--- /dev/null
+++ b/include/net/netfilter/nf_conntrack_timeout.h
@@ -0,0 +1,78 @@
+#ifndef _NF_CONNTRACK_TIMEOUT_H
+#define _NF_CONNTRACK_TIMEOUT_H
+
+#include <net/net_namespace.h>
+#include <linux/netfilter/nf_conntrack_common.h>
+#include <linux/netfilter/nf_conntrack_tuple_common.h>
+#include <net/netfilter/nf_conntrack.h>
+#include <net/netfilter/nf_conntrack_extend.h>
+
+#define CTNL_TIMEOUT_NAME_MAX	32
+
+struct ctnl_timeout {
+	struct list_head	head;
+	struct rcu_head		rcu_head;
+	atomic_t		refcnt;
+	char			name[CTNL_TIMEOUT_NAME_MAX];
+	__u16			l3num;
+	__u8			l4num;
+	char			data[0];
+};
+
+struct nf_conn_timeout {
+	struct ctnl_timeout	*timeout;
+};
+
+#define NF_CT_TIMEOUT_EXT_DATA(__t) (unsigned int *) &((__t)->timeout->data)
+
+static inline
+struct nf_conn_timeout *nf_ct_timeout_find(const struct nf_conn *ct)
+{
+#ifdef CONFIG_NF_CONNTRACK_TIMEOUT
+	return nf_ct_ext_find(ct, NF_CT_EXT_TIMEOUT);
+#else
+	return NULL;
+#endif
+}
+
+static inline
+struct nf_conn_timeout *nf_ct_timeout_ext_add(struct nf_conn *ct,
+					      struct ctnl_timeout *timeout,
+					      gfp_t gfp)
+{
+#ifdef CONFIG_NF_CONNTRACK_TIMEOUT
+	struct nf_conn_timeout *timeout_ext;
+
+	timeout_ext = nf_ct_ext_add(ct, NF_CT_EXT_TIMEOUT, gfp);
+	if (timeout_ext == NULL)
+		return NULL;
+
+	timeout_ext->timeout = timeout;
+
+	return timeout_ext;
+#else
+	return NULL;
+#endif
+};
+
+#ifdef CONFIG_NF_CONNTRACK_TIMEOUT
+extern int nf_conntrack_timeout_init(struct net *net);
+extern void nf_conntrack_timeout_fini(struct net *net);
+#else
+static inline int nf_conntrack_timeout_init(struct net *net)
+{
+        return 0;
+}
+
+static inline void nf_conntrack_timeout_fini(struct net *net)
+{
+        return;
+}
+#endif /* CONFIG_NF_CONNTRACK_TIMEOUT */
+
+#ifdef CONFIG_NF_CONNTRACK_TIMEOUT
+extern struct ctnl_timeout *(*nf_ct_timeout_find_get_hook)(const char *name);
+extern void (*nf_ct_timeout_put_hook)(struct ctnl_timeout *timeout);
+#endif
+
+#endif /* _NF_CONNTRACK_TIMEOUT_H */