LXR linux/include/net/netfilter/nf

   1#ifndef _NF_NAT_H
   2#define _NF_NAT_H
   3#include <linux/netfilter_ipv4.h>
   4#include <net/netfilter/nf_conntrack_tuple.h>
   5
   6#define NF_NAT_MAPPING_TYPE_MAX_NAMELEN 16
   7
   8enum nf_nat_manip_type
   9{
  10        IP_NAT_MANIP_SRC,
  11        IP_NAT_MANIP_DST
  12};
  13
  14/* SRC manip occurs POST_ROUTING or LOCAL_IN */
  15#define HOOK2MANIP(hooknum) ((hooknum) != NF_IP_POST_ROUTING && (hooknum) != NF_IP_LOCAL_IN)
  16
  17#define IP_NAT_RANGE_MAP_IPS 1
  18#define IP_NAT_RANGE_PROTO_SPECIFIED 2
  19#define IP_NAT_RANGE_PROTO_RANDOM 4
  20
  21/* NAT sequence number modifications */
  22struct nf_nat_seq {
  23        /* position of the last TCP sequence number modification (if any) */
  24        u_int32_t correction_pos;
  25
  26        /* sequence number offset before and after last modification */
  27        int16_t offset_before, offset_after;
  28};
  29
  30/* Single range specification. */
  31struct nf_nat_range
  32{
  33        /* Set to OR of flags above. */
  34        unsigned int flags;
  35
  36        /* Inclusive: network order. */
  37        __be32 min_ip, max_ip;
  38
  39        /* Inclusive: network order */
  40        union nf_conntrack_man_proto min, max;
  41};
  42
  43/* For backwards compat: don't use in modern code. */
  44struct nf_nat_multi_range_compat
  45{
  46        unsigned int rangesize; /* Must be 1. */
  47
  48        /* hangs off end. */
  49        struct nf_nat_range range[1];
  50};
  51
  52#ifdef __KERNEL__
  53#include <linux/list.h>
  54#include <linux/netfilter/nf_conntrack_pptp.h>
  55#include <net/netfilter/nf_conntrack_extend.h>
  56
  57/* per conntrack: nat application helper private data */
  58union nf_conntrack_nat_help
  59{
  60        /* insert nat helper private data here */
  61        struct nf_nat_pptp nat_pptp_info;
  62};
  63
  64struct nf_conn;
  65
  66/* The structure embedded in the conntrack structure. */
  67struct nf_conn_nat
  68{
  69        struct hlist_node bysource;
  70        struct nf_nat_seq seq[IP_CT_DIR_MAX];
  71        struct nf_conn *ct;
  72        union nf_conntrack_nat_help help;
  73#if defined(CONFIG_IP_NF_TARGET_MASQUERADE) || \
  74    defined(CONFIG_IP_NF_TARGET_MASQUERADE_MODULE)
  75        int masq_index;
  76#endif
  77};
  78
  79/* Set up the info structure to map into this range. */
  80extern unsigned int nf_nat_setup_info(struct nf_conn *ct,
  81                                      const struct nf_nat_range *range,
  82                                      unsigned int hooknum);
  83
  84/* Is this tuple already taken? (not by us)*/
  85extern int nf_nat_used_tuple(const struct nf_conntrack_tuple *tuple,
  86                             const struct nf_conn *ignored_conntrack);
  87
  88static inline struct nf_conn_nat *nfct_nat(const struct nf_conn *ct)
  89{
  90        return nf_ct_ext_find(ct, NF_CT_EXT_NAT);
  91}
  92
  93#else  /* !__KERNEL__: iptables wants this to compile. */
  94#define nf_nat_multi_range nf_nat_multi_range_compat
  95#endif /*__KERNEL__*/
  96#endif
  97