LXR linux/include/net/netfilter/nf

   1#ifndef _NF_NAT_H
   2#define _NF_NAT_H
   3#include <linux/netfilter_ipv4.h>
   4#include <linux/netfilter/nf_nat.h>
   5#include <net/netfilter/nf_conntrack_tuple.h>
   6
   7enum nf_nat_manip_type {
   8        NF_NAT_MANIP_SRC,
   9        NF_NAT_MANIP_DST
  10};
  11
  12/* SRC manip occurs POST_ROUTING or LOCAL_IN */
  13#define HOOK2MANIP(hooknum) ((hooknum) != NF_INET_POST_ROUTING && \
  14                             (hooknum) != NF_INET_LOCAL_IN)
  15
  16#include <linux/list.h>
  17#include <linux/netfilter/nf_conntrack_pptp.h>
  18#include <net/netfilter/nf_conntrack_extend.h>
  19
  20/* per conntrack: nat application helper private data */
  21union nf_conntrack_nat_help {
  22        /* insert nat helper private data here */
  23#if defined(CONFIG_NF_NAT_PPTP) || defined(CONFIG_NF_NAT_PPTP_MODULE)
  24        struct nf_nat_pptp nat_pptp_info;
  25#endif
  26};
  27
  28struct nf_conn;
  29
  30/* The structure embedded in the conntrack structure. */
  31struct nf_conn_nat {
  32        struct hlist_node bysource;
  33        struct nf_conn *ct;
  34        union nf_conntrack_nat_help help;
  35#if defined(CONFIG_IP_NF_TARGET_MASQUERADE) || \
  36    defined(CONFIG_IP_NF_TARGET_MASQUERADE_MODULE) || \
  37    defined(CONFIG_IP6_NF_TARGET_MASQUERADE) || \
  38    defined(CONFIG_IP6_NF_TARGET_MASQUERADE_MODULE)
  39        int masq_index;
  40#endif
  41};
  42
  43/* Set up the info structure to map into this range. */
  44unsigned int nf_nat_setup_info(struct nf_conn *ct,
  45                               const struct nf_nat_range *range,
  46                               enum nf_nat_manip_type maniptype);
  47
  48extern unsigned int nf_nat_alloc_null_binding(struct nf_conn *ct,
  49                                              unsigned int hooknum);
  50
  51/* Is this tuple already taken? (not by us)*/
  52int nf_nat_used_tuple(const struct nf_conntrack_tuple *tuple,
  53                      const struct nf_conn *ignored_conntrack);
  54
  55static inline struct nf_conn_nat *nfct_nat(const struct nf_conn *ct)
  56{
  57#if defined(CONFIG_NF_NAT) || defined(CONFIG_NF_NAT_MODULE)
  58        return nf_ct_ext_find(ct, NF_CT_EXT_NAT);
  59#else
  60        return NULL;
  61#endif
  62}
  63
  64static inline bool nf_nat_oif_changed(unsigned int hooknum,
  65                                      enum ip_conntrack_info ctinfo,
  66                                      struct nf_conn_nat *nat,
  67                                      const struct net_device *out)
  68{
  69#if IS_ENABLED(CONFIG_IP_NF_TARGET_MASQUERADE) || \
  70    IS_ENABLED(CONFIG_IP6_NF_TARGET_MASQUERADE)
  71        return nat->masq_index && hooknum == NF_INET_POST_ROUTING &&
  72               CTINFO2DIR(ctinfo) == IP_CT_DIR_ORIGINAL &&
  73               nat->masq_index != out->ifindex;
  74#else
  75        return false;
  76#endif
  77}
  78
  79#endif
  80