LXR linux/include/net/netfilter/nf_conntrack

   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
   8enum 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_SEQADJ,
  14        NF_CT_EXT_ACCT,
  15#ifdef CONFIG_NF_CONNTRACK_EVENTS
  16        NF_CT_EXT_ECACHE,
  17#endif
  18#ifdef CONFIG_NF_CONNTRACK_ZONES
  19        NF_CT_EXT_ZONE,
  20#endif
  21#ifdef CONFIG_NF_CONNTRACK_TIMESTAMP
  22        NF_CT_EXT_TSTAMP,
  23#endif
  24#ifdef CONFIG_NF_CONNTRACK_TIMEOUT
  25        NF_CT_EXT_TIMEOUT,
  26#endif
  27#ifdef CONFIG_NF_CONNTRACK_LABELS
  28        NF_CT_EXT_LABELS,
  29#endif
  30#if IS_ENABLED(CONFIG_NETFILTER_SYNPROXY)
  31        NF_CT_EXT_SYNPROXY,
  32#endif
  33        NF_CT_EXT_NUM,
  34};
  35
  36#define NF_CT_EXT_HELPER_TYPE struct nf_conn_help
  37#define NF_CT_EXT_NAT_TYPE struct nf_conn_nat
  38#define NF_CT_EXT_SEQADJ_TYPE struct nf_conn_seqadj
  39#define NF_CT_EXT_ACCT_TYPE struct nf_conn_acct
  40#define NF_CT_EXT_ECACHE_TYPE struct nf_conntrack_ecache
  41#define NF_CT_EXT_ZONE_TYPE struct nf_conntrack_zone
  42#define NF_CT_EXT_TSTAMP_TYPE struct nf_conn_tstamp
  43#define NF_CT_EXT_TIMEOUT_TYPE struct nf_conn_timeout
  44#define NF_CT_EXT_LABELS_TYPE struct nf_conn_labels
  45#define NF_CT_EXT_SYNPROXY_TYPE struct nf_conn_synproxy
  46
  47/* Extensions: optional stuff which isn't permanently in struct. */
  48struct nf_ct_ext {
  49        struct rcu_head rcu;
  50        u16 offset[NF_CT_EXT_NUM];
  51        u16 len;
  52        char data[0];
  53};
  54
  55static inline bool __nf_ct_ext_exist(const struct nf_ct_ext *ext, u8 id)
  56{
  57        return !!ext->offset[id];
  58}
  59
  60static inline bool nf_ct_ext_exist(const struct nf_conn *ct, u8 id)
  61{
  62        return (ct->ext && __nf_ct_ext_exist(ct->ext, id));
  63}
  64
  65static inline void *__nf_ct_ext_find(const struct nf_conn *ct, u8 id)
  66{
  67        if (!nf_ct_ext_exist(ct, id))
  68                return NULL;
  69
  70        return (void *)ct->ext + ct->ext->offset[id];
  71}
  72#define nf_ct_ext_find(ext, id) \
  73        ((id##_TYPE *)__nf_ct_ext_find((ext), (id)))
  74
  75/* Destroy all relationships */
  76void __nf_ct_ext_destroy(struct nf_conn *ct);
  77static inline void nf_ct_ext_destroy(struct nf_conn *ct)
  78{
  79        if (ct->ext)
  80                __nf_ct_ext_destroy(ct);
  81}
  82
  83/* Free operation. If you want to free a object referred from private area,
  84 * please implement __nf_ct_ext_free() and call it.
  85 */
  86static inline void nf_ct_ext_free(struct nf_conn *ct)
  87{
  88        if (ct->ext)
  89                kfree_rcu(ct->ext, rcu);
  90}
  91
  92/* Add this type, returns pointer to data or NULL. */
  93void *__nf_ct_ext_add_length(struct nf_conn *ct, enum nf_ct_ext_id id,
  94                             size_t var_alloc_len, gfp_t gfp);
  95
  96#define nf_ct_ext_add(ct, id, gfp) \
  97        ((id##_TYPE *)__nf_ct_ext_add_length((ct), (id), 0, (gfp)))
  98#define nf_ct_ext_add_length(ct, id, len, gfp) \
  99        ((id##_TYPE *)__nf_ct_ext_add_length((ct), (id), (len), (gfp)))
 100
 101#define NF_CT_EXT_F_PREALLOC    0x0001
 102
 103struct nf_ct_ext_type {
 104        /* Destroys relationships (can be NULL). */
 105        void (*destroy)(struct nf_conn *ct);
 106        /* Called when realloacted (can be NULL).
 107           Contents has already been moved. */
 108        void (*move)(void *new, void *old);
 109
 110        enum nf_ct_ext_id id;
 111
 112        unsigned int flags;
 113
 114        /* Length and min alignment. */
 115        u8 len;
 116        u8 align;
 117        /* initial size of nf_ct_ext. */
 118        u8 alloc_size;
 119};
 120
 121int nf_ct_extend_register(struct nf_ct_ext_type *type);
 122void nf_ct_extend_unregister(struct nf_ct_ext_type *type);
 123#endif /* _NF_CONNTRACK_EXTEND_H */
 124