include/net/netfilter/nf_conntrack_extend.h

   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 IS_ENABLED(CONFIG_NF_NAT)
  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 #if IS_ENABLED(CONFIG_NET_ACT_CT)
  32         NF_CT_EXT_ACT_CT,
  33 #endif
  34         NF_CT_EXT_NUM,
  35 };
  36
  37 /* Extensions: optional stuff which isn't permanently in struct. */
  38 struct nf_ct_ext {
  39         u8 offset[NF_CT_EXT_NUM];
  40         u8 len;
  41         unsigned int gen_id;
  42         char data[] __aligned(8);
  43 };
  44
  45 static inline bool __nf_ct_ext_exist(const struct nf_ct_ext *ext, u8 id)
  46 {
  47         return !!ext->offset[id];
  48 }
  49
  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
  55 void *__nf_ct_ext_find(const struct nf_ct_ext *ext, u8 id);
  56
  57 static inline void *nf_ct_ext_find(const struct nf_conn *ct, u8 id)
  58 {
  59         struct nf_ct_ext *ext = ct->ext;
  60
  61         if (!ext || !__nf_ct_ext_exist(ext, id))
  62                 return NULL;
  63
  64         if (unlikely(ext->gen_id))
  65                 return __nf_ct_ext_find(ext, id);
  66
  67         return (void *)ct->ext + ct->ext->offset[id];
  68 }
  69
  70 /* Add this type, returns pointer to data or NULL. */
  71 void *nf_ct_ext_add(struct nf_conn *ct, enum nf_ct_ext_id id, gfp_t gfp);
  72
  73 /* ext genid.  if ext->id != ext_genid, extensions cannot be used
  74  * anymore unless conntrack has CONFIRMED bit set.
  75  */
  76 extern atomic_t nf_conntrack_ext_genid;
  77 void nf_ct_ext_bump_genid(void);
  78
  79 #endif /* _NF_CONNTRACK_EXTEND_H */