ip_nat.h
上传用户:lgb322
上传日期:2013-02-24
资源大小:30529k
文件大小:3k
- #ifndef _IP_NAT_H
- #define _IP_NAT_H
- #include <linux/netfilter_ipv4.h>
- #include <linux/netfilter_ipv4/ip_conntrack_tuple.h>
- #define IP_NAT_MAPPING_TYPE_MAX_NAMELEN 16
- enum ip_nat_manip_type
- {
- IP_NAT_MANIP_SRC,
- IP_NAT_MANIP_DST
- };
- /* SRC manip occurs only on POST_ROUTING */
- #define HOOK2MANIP(hooknum) ((hooknum) != NF_IP_POST_ROUTING)
- /* 2.3.19 (I hope) will define this in linux/netfilter_ipv4.h. */
- #ifndef SO_ORIGINAL_DST
- #define SO_ORIGINAL_DST 80
- #endif
- #define IP_NAT_RANGE_MAP_IPS 1
- #define IP_NAT_RANGE_PROTO_SPECIFIED 2
- /* Used internally by get_unique_tuple(). */
- #define IP_NAT_RANGE_FULL 4
- /* NAT sequence number modifications */
- struct ip_nat_seq {
- /* position of the last TCP sequence number
- * modification (if any) */
- u_int32_t correction_pos;
- /* sequence number offset before and after last modification */
- int32_t offset_before, offset_after;
- };
- /* Single range specification. */
- struct ip_nat_range
- {
- /* Set to OR of flags above. */
- unsigned int flags;
- /* Inclusive: network order. */
- u_int32_t min_ip, max_ip;
- /* Inclusive: network order */
- union ip_conntrack_manip_proto min, max;
- };
- /* A range consists of an array of 1 or more ip_nat_range */
- struct ip_nat_multi_range
- {
- unsigned int rangesize;
- /* hangs off end. */
- struct ip_nat_range range[1];
- };
- #ifdef __KERNEL__
- #include <linux/list.h>
- #include <linux/netfilter_ipv4/lockhelp.h>
- /* Protects NAT hash tables, and NAT-private part of conntracks. */
- DECLARE_RWLOCK_EXTERN(ip_nat_lock);
- /* Hashes for by-source and IP/protocol. */
- struct ip_nat_hash
- {
- struct list_head list;
- /* conntrack we're embedded in: NULL if not in hash. */
- struct ip_conntrack *conntrack;
- };
- /* Worst case: local-out manip + 1 post-routing, and reverse dirn. */
- #define IP_NAT_MAX_MANIPS (2*3)
- struct ip_nat_info_manip
- {
- /* The direction. */
- u_int8_t direction;
- /* Which hook the manipulation happens on. */
- u_int8_t hooknum;
- /* The manipulation type. */
- u_int8_t maniptype;
- /* Manipulations to occur at each conntrack in this dirn. */
- struct ip_conntrack_manip manip;
- };
-
- /* The structure embedded in the conntrack structure. */
- struct ip_nat_info
- {
- /* Set to zero when conntrack created: bitmask of maniptypes */
- int initialized;
- unsigned int num_manips;
- /* Manipulations to be done on this conntrack. */
- struct ip_nat_info_manip manips[IP_NAT_MAX_MANIPS];
- /* The mapping type which created us (NULL for null mapping). */
- const struct ip_nat_mapping_type *mtype;
- struct ip_nat_hash bysource, byipsproto;
- /* Helper (NULL if none). */
- struct ip_nat_helper *helper;
- struct ip_nat_seq seq[IP_CT_DIR_MAX];
- };
- /* Set up the info structure to map into this range. */
- extern unsigned int ip_nat_setup_info(struct ip_conntrack *conntrack,
- const struct ip_nat_multi_range *mr,
- unsigned int hooknum);
- /* Is this tuple already taken? (not by us)*/
- extern int ip_nat_used_tuple(const struct ip_conntrack_tuple *tuple,
- const struct ip_conntrack *ignored_conntrack);
- /* Calculate relative checksum. */
- extern u_int16_t ip_nat_cheat_check(u_int32_t oldvalinv,
- u_int32_t newval,
- u_int16_t oldcheck);
- #endif /*__KERNEL__*/
- #endif