1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef _NF_CONNTRACK_EXTEND_H 3 #define _NF_CONNTRACK_EXTEND_H 4 5 #include <linux/slab.h> 6 7 #include <net/netfilter/nf_conntrack.h> 8 9 enum nf_ct_ext_id { 10 NF_CT_EXT_HELPER, 11 #if defined(CONFIG_NF_NAT) || defined(CONFIG_NF_NAT_MODULE) 12 NF_CT_EXT_NAT, 13 #endif 14 NF_CT_EXT_SEQADJ, 15 NF_CT_EXT_ACCT, 16 #ifdef CONFIG_NF_CONNTRACK_EVENTS 17 NF_CT_EXT_ECACHE, 18 #endif 19 #ifdef CONFIG_NF_CONNTRACK_TIMESTAMP 20 NF_CT_EXT_TSTAMP, 21 #endif 22 #ifdef CONFIG_NF_CONNTRACK_TIMEOUT 23 NF_CT_EXT_TIMEOUT, 24 #endif 25 #ifdef CONFIG_NF_CONNTRACK_LABELS 26 NF_CT_EXT_LABELS, 27 #endif 28 #if IS_ENABLED(CONFIG_NETFILTER_SYNPROXY) 29 NF_CT_EXT_SYNPROXY, 30 #endif 31 NF_CT_EXT_NUM, 32 }; 33 34 #define NF_CT_EXT_HELPER_TYPE struct nf_conn_help 35 #define NF_CT_EXT_NAT_TYPE struct nf_conn_nat 36 #define NF_CT_EXT_SEQADJ_TYPE struct nf_conn_seqadj 37 #define NF_CT_EXT_ACCT_TYPE struct nf_conn_acct 38 #define NF_CT_EXT_ECACHE_TYPE struct nf_conntrack_ecache 39 #define NF_CT_EXT_TSTAMP_TYPE struct nf_conn_tstamp 40 #define NF_CT_EXT_TIMEOUT_TYPE struct nf_conn_timeout 41 #define NF_CT_EXT_LABELS_TYPE struct nf_conn_labels 42 #define NF_CT_EXT_SYNPROXY_TYPE struct nf_conn_synproxy 43 44 /* Extensions: optional stuff which isn't permanently in struct. */ 45 struct nf_ct_ext { 46 struct rcu_head rcu; 47 u8 offset[NF_CT_EXT_NUM]; 48 u8 len; 49 char data[0]; 50 }; 51 52 static inline bool __nf_ct_ext_exist(const struct nf_ct_ext *ext, u8 id) 53 { 54 return !!ext->offset[id]; 55 } 56 57 static inline bool nf_ct_ext_exist(const struct nf_conn *ct, u8 id) 58 { 59 return (ct->ext && __nf_ct_ext_exist(ct->ext, id)); 60 } 61 62 static inline void *__nf_ct_ext_find(const struct nf_conn *ct, u8 id) 63 { 64 if (!nf_ct_ext_exist(ct, id)) 65 return NULL; 66 67 return (void *)ct->ext + ct->ext->offset[id]; 68 } 69 #define nf_ct_ext_find(ext, id) \ 70 ((id##_TYPE *)__nf_ct_ext_find((ext), (id))) 71 72 /* Destroy all relationships */ 73 void nf_ct_ext_destroy(struct nf_conn *ct); 74 75 /* Free operation. If you want to free a object referred from private area, 76 * please implement __nf_ct_ext_free() and call it. 77 */ 78 static inline void nf_ct_ext_free(struct nf_conn *ct) 79 { 80 if (ct->ext) 81 kfree_rcu(ct->ext, rcu); 82 } 83 84 /* Add this type, returns pointer to data or NULL. */ 85 void *nf_ct_ext_add(struct nf_conn *ct, enum nf_ct_ext_id id, gfp_t gfp); 86 87 struct nf_ct_ext_type { 88 /* Destroys relationships (can be NULL). */ 89 void (*destroy)(struct nf_conn *ct); 90 91 enum nf_ct_ext_id id; 92 93 /* Length and min alignment. */ 94 u8 len; 95 u8 align; 96 }; 97 98 int nf_ct_extend_register(const struct nf_ct_ext_type *type); 99 void nf_ct_extend_unregister(const struct nf_ct_ext_type *type); 100 #endif /* _NF_CONNTRACK_EXTEND_H */ 101