1 #ifndef _NF_CONNTRACK_EXTEND_H 2 #define _NF_CONNTRACK_EXTEND_H 3 4 #include <net/netfilter/nf_conntrack.h> 5 6 enum nf_ct_ext_id 7 { 8 NF_CT_EXT_HELPER, 9 NF_CT_EXT_NAT, 10 NF_CT_EXT_NUM, 11 }; 12 13 #define NF_CT_EXT_HELPER_TYPE struct nf_conn_help 14 #define NF_CT_EXT_NAT_TYPE struct nf_conn_nat 15 16 /* Extensions: optional stuff which isn't permanently in struct. */ 17 struct nf_ct_ext { 18 u8 offset[NF_CT_EXT_NUM]; 19 u8 len; 20 char data[0]; 21 }; 22 23 static inline int nf_ct_ext_exist(const struct nf_conn *ct, u8 id) 24 { 25 return (ct->ext && ct->ext->offset[id]); 26 } 27 28 static inline void *__nf_ct_ext_find(const struct nf_conn *ct, u8 id) 29 { 30 if (!nf_ct_ext_exist(ct, id)) 31 return NULL; 32 33 return (void *)ct->ext + ct->ext->offset[id]; 34 } 35 #define nf_ct_ext_find(ext, id) \ 36 ((id##_TYPE *)__nf_ct_ext_find((ext), (id))) 37 38 /* Destroy all relationships */ 39 extern void __nf_ct_ext_destroy(struct nf_conn *ct); 40 static inline void nf_ct_ext_destroy(struct nf_conn *ct) 41 { 42 if (ct->ext) 43 __nf_ct_ext_destroy(ct); 44 } 45 46 /* Free operation. If you want to free a object referred from private area, 47 * please implement __nf_ct_ext_free() and call it. 48 */ 49 static inline void nf_ct_ext_free(struct nf_conn *ct) 50 { 51 if (ct->ext) 52 kfree(ct->ext); 53 } 54 55 /* Add this type, returns pointer to data or NULL. */ 56 void * 57 __nf_ct_ext_add(struct nf_conn *ct, enum nf_ct_ext_id id, gfp_t gfp); 58 #define nf_ct_ext_add(ct, id, gfp) \ 59 ((id##_TYPE *)__nf_ct_ext_add((ct), (id), (gfp))) 60 61 #define NF_CT_EXT_F_PREALLOC 0x0001 62 63 struct nf_ct_ext_type 64 { 65 /* Destroys relationships (can be NULL). */ 66 void (*destroy)(struct nf_conn *ct); 67 /* Called when realloacted (can be NULL). 68 Contents has already been moved. */ 69 void (*move)(void *new, void *old); 70 71 enum nf_ct_ext_id id; 72 73 unsigned int flags; 74 75 /* Length and min alignment. */ 76 u8 len; 77 u8 align; 78 /* initial size of nf_ct_ext. */ 79 u8 alloc_size; 80 }; 81 82 int nf_ct_extend_register(struct nf_ct_ext_type *type); 83 void nf_ct_extend_unregister(struct nf_ct_ext_type *type); 84 #endif /* _NF_CONNTRACK_EXTEND_H */ 85