1 #ifndef _NF_CONNTRACK_EXTEND_H
2 #define _NF_CONNTRACK_EXTEND_H
3
4 #include <linux/slab.h>
5
6 #include <net/netfilter/nf_conntrack.h>
7
8 enum nf_ct_ext_id {
9 NF_CT_EXT_HELPER,
10 #if defined(CONFIG_NF_NAT) || defined(CONFIG_NF_NAT_MODULE)
11 NF_CT_EXT_NAT,
12 #endif
13 NF_CT_EXT_ACCT,
14 #ifdef CONFIG_NF_CONNTRACK_EVENTS
15 NF_CT_EXT_ECACHE,
16 #endif
17 #ifdef CONFIG_NF_CONNTRACK_ZONES
18 NF_CT_EXT_ZONE,
19 #endif
20 #ifdef CONFIG_NF_CONNTRACK_TIMESTAMP
21 NF_CT_EXT_TSTAMP,
22 #endif
23 #ifdef CONFIG_NF_CONNTRACK_TIMEOUT
24 NF_CT_EXT_TIMEOUT,
25 #endif
26 NF_CT_EXT_NUM,
27 };
28
29 #define NF_CT_EXT_HELPER_TYPE struct nf_conn_help
30 #define NF_CT_EXT_NAT_TYPE struct nf_conn_nat
31 #define NF_CT_EXT_ACCT_TYPE struct nf_conn_counter
32 #define NF_CT_EXT_ECACHE_TYPE struct nf_conntrack_ecache
33 #define NF_CT_EXT_ZONE_TYPE struct nf_conntrack_zone
34 #define NF_CT_EXT_TSTAMP_TYPE struct nf_conn_tstamp
35 #define NF_CT_EXT_TIMEOUT_TYPE struct nf_conn_timeout
36
37 /* Extensions: optional stuff which isn't permanently in struct. */
38 struct nf_ct_ext {
39 struct rcu_head rcu;
40 u16 offset[NF_CT_EXT_NUM];
41 u16 len;
42 char data[0];
43 };
44
__nf_ct_ext_exist(const struct nf_ct_ext * ext,u8 id)45 static inline bool __nf_ct_ext_exist(const struct nf_ct_ext *ext, u8 id)
46 {
47 return !!ext->offset[id];
48 }
49
nf_ct_ext_exist(const struct nf_conn * ct,u8 id)50 static inline bool nf_ct_ext_exist(const struct nf_conn *ct, u8 id)
51 {
52 return (ct->ext && __nf_ct_ext_exist(ct->ext, id));
53 }
54
__nf_ct_ext_find(const struct nf_conn * ct,u8 id)55 static inline void *__nf_ct_ext_find(const struct nf_conn *ct, u8 id)
56 {
57 if (!nf_ct_ext_exist(ct, id))
58 return NULL;
59
60 return (void *)ct->ext + ct->ext->offset[id];
61 }
62 #define nf_ct_ext_find(ext, id) \
63 ((id##_TYPE *)__nf_ct_ext_find((ext), (id)))
64
65 /* Destroy all relationships */
66 extern void __nf_ct_ext_destroy(struct nf_conn *ct);
nf_ct_ext_destroy(struct nf_conn * ct)67 static inline void nf_ct_ext_destroy(struct nf_conn *ct)
68 {
69 if (ct->ext)
70 __nf_ct_ext_destroy(ct);
71 }
72
73 /* Free operation. If you want to free a object referred from private area,
74 * please implement __nf_ct_ext_free() and call it.
75 */
nf_ct_ext_free(struct nf_conn * ct)76 static inline void nf_ct_ext_free(struct nf_conn *ct)
77 {
78 if (ct->ext)
79 kfree(ct->ext);
80 }
81
82 /* Add this type, returns pointer to data or NULL. */
83 void *
84 __nf_ct_ext_add(struct nf_conn *ct, enum nf_ct_ext_id id, gfp_t gfp);
85 #define nf_ct_ext_add(ct, id, gfp) \
86 ((id##_TYPE *)__nf_ct_ext_add((ct), (id), (gfp)))
87
88 #define NF_CT_EXT_F_PREALLOC 0x0001
89
90 struct nf_ct_ext_type {
91 /* Destroys relationships (can be NULL). */
92 void (*destroy)(struct nf_conn *ct);
93 /* Called when realloacted (can be NULL).
94 Contents has already been moved. */
95 void (*move)(void *new, void *old);
96
97 enum nf_ct_ext_id id;
98
99 unsigned int flags;
100
101 /* Length and min alignment. */
102 u8 len;
103 u8 align;
104 /* initial size of nf_ct_ext. */
105 u8 alloc_size;
106 };
107
108 int nf_ct_extend_register(struct nf_ct_ext_type *type);
109 void nf_ct_extend_unregister(struct nf_ct_ext_type *type);
110 #endif /* _NF_CONNTRACK_EXTEND_H */
111