1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _NF_CONNTRACK_TIMEOUT_H
3 #define _NF_CONNTRACK_TIMEOUT_H
4 
5 #include <net/net_namespace.h>
6 #include <linux/netfilter/nf_conntrack_common.h>
7 #include <linux/netfilter/nf_conntrack_tuple_common.h>
8 #include <linux/refcount.h>
9 #include <net/netfilter/nf_conntrack.h>
10 #include <net/netfilter/nf_conntrack_extend.h>
11 
12 #define CTNL_TIMEOUT_NAME_MAX	32
13 
14 struct nf_ct_timeout {
15 	__u16			l3num;
16 	const struct nf_conntrack_l4proto *l4proto;
17 	char			data[];
18 };
19 
20 struct ctnl_timeout {
21 	struct list_head	head;
22 	struct rcu_head		rcu_head;
23 	refcount_t		refcnt;
24 	char			name[CTNL_TIMEOUT_NAME_MAX];
25 	struct nf_ct_timeout	timeout;
26 };
27 
28 struct nf_conn_timeout {
29 	struct nf_ct_timeout __rcu *timeout;
30 };
31 
32 static inline unsigned int *
33 nf_ct_timeout_data(const struct nf_conn_timeout *t)
34 {
35 #ifdef CONFIG_NF_CONNTRACK_TIMEOUT
36 	struct nf_ct_timeout *timeout;
37 
38 	timeout = rcu_dereference(t->timeout);
39 	if (timeout == NULL)
40 		return NULL;
41 
42 	return (unsigned int *)timeout->data;
43 #else
44 	return NULL;
45 #endif
46 }
47 
48 static inline
49 struct nf_conn_timeout *nf_ct_timeout_find(const struct nf_conn *ct)
50 {
51 #ifdef CONFIG_NF_CONNTRACK_TIMEOUT
52 	return nf_ct_ext_find(ct, NF_CT_EXT_TIMEOUT);
53 #else
54 	return NULL;
55 #endif
56 }
57 
58 static inline
59 struct nf_conn_timeout *nf_ct_timeout_ext_add(struct nf_conn *ct,
60 					      struct nf_ct_timeout *timeout,
61 					      gfp_t gfp)
62 {
63 #ifdef CONFIG_NF_CONNTRACK_TIMEOUT
64 	struct nf_conn_timeout *timeout_ext;
65 
66 	timeout_ext = nf_ct_ext_add(ct, NF_CT_EXT_TIMEOUT, gfp);
67 	if (timeout_ext == NULL)
68 		return NULL;
69 
70 	rcu_assign_pointer(timeout_ext->timeout, timeout);
71 
72 	return timeout_ext;
73 #else
74 	return NULL;
75 #endif
76 };
77 
78 static inline unsigned int *nf_ct_timeout_lookup(const struct nf_conn *ct)
79 {
80 	unsigned int *timeouts = NULL;
81 #ifdef CONFIG_NF_CONNTRACK_TIMEOUT
82 	struct nf_conn_timeout *timeout_ext;
83 
84 	timeout_ext = nf_ct_timeout_find(ct);
85 	if (timeout_ext)
86 		timeouts = nf_ct_timeout_data(timeout_ext);
87 #endif
88 	return timeouts;
89 }
90 
91 #ifdef CONFIG_NF_CONNTRACK_TIMEOUT
92 void nf_ct_untimeout(struct net *net, struct nf_ct_timeout *timeout);
93 int nf_ct_set_timeout(struct net *net, struct nf_conn *ct, u8 l3num, u8 l4num,
94 		      const char *timeout_name);
95 void nf_ct_destroy_timeout(struct nf_conn *ct);
96 #else
97 static inline int nf_ct_set_timeout(struct net *net, struct nf_conn *ct,
98 				    u8 l3num, u8 l4num,
99 				    const char *timeout_name)
100 {
101 	return -EOPNOTSUPP;
102 }
103 
104 static inline void nf_ct_destroy_timeout(struct nf_conn *ct)
105 {
106 	return;
107 }
108 #endif /* CONFIG_NF_CONNTRACK_TIMEOUT */
109 
110 #ifdef CONFIG_NF_CONNTRACK_TIMEOUT
111 struct nf_ct_timeout_hooks {
112 	struct nf_ct_timeout *(*timeout_find_get)(struct net *net, const char *name);
113 	void (*timeout_put)(struct nf_ct_timeout *timeout);
114 };
115 
116 extern const struct nf_ct_timeout_hooks *nf_ct_timeout_hook;
117 #endif
118 
119 #endif /* _NF_CONNTRACK_TIMEOUT_H */
120