include/net/netfilter/nf_nat.h

   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
   8 enum 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
  20 /* NAT sequence number modifications */
  21 struct nf_nat_seq {
  22         /* position of the last TCP sequence number modification (if any) */
  23         u_int32_t correction_pos;
  24
  25         /* sequence number offset before and after last modification */
  26         int16_t offset_before, offset_after;
  27 };
  28
  29 /* Single range specification. */
  30 struct nf_nat_range
  31 {
  32         /* Set to OR of flags above. */
  33         unsigned int flags;
  34
  35         /* Inclusive: network order. */
  36         __be32 min_ip, max_ip;
  37
  38         /* Inclusive: network order */
  39         union nf_conntrack_man_proto min, max;
  40 };
  41
  42 /* For backwards compat: don't use in modern code. */
  43 struct nf_nat_multi_range_compat
  44 {
  45         unsigned int rangesize; /* Must be 1. */
  46
  47         /* hangs off end. */
  48         struct nf_nat_range range[1];
  49 };
  50
  51 #ifdef __KERNEL__
  52 #include <linux/list.h>
  53
  54 /* The structure embedded in the conntrack structure. */
  55 struct nf_nat_info
  56 {
  57         struct list_head bysource;
  58         struct nf_nat_seq seq[IP_CT_DIR_MAX];
  59 };
  60
  61 struct nf_conn;
  62
  63 /* Set up the info structure to map into this range. */
  64 extern unsigned int nf_nat_setup_info(struct nf_conn *ct,
  65                                       const struct nf_nat_range *range,
  66                                       unsigned int hooknum);
  67
  68 /* Is this tuple already taken? (not by us)*/
  69 extern int nf_nat_used_tuple(const struct nf_conntrack_tuple *tuple,
  70                              const struct nf_conn *ignored_conntrack);
  71
  72 extern int nf_nat_module_is_loaded;
  73
  74 #else  /* !__KERNEL__: iptables wants this to compile. */
  75 #define nf_nat_multi_range nf_nat_multi_range_compat
  76 #endif /*__KERNEL__*/
  77 #endif