root/include/net/netfilter/nf_nat_protocol.h

INCLUDED FROM

/* Header for use in defining a given protocol. */
#ifndef _NF_NAT_PROTOCOL_H
#define _NF_NAT_PROTOCOL_H
#include <net/netfilter/nf_nat.h>
#include <linux/netfilter/nfnetlink_conntrack.h>

struct nf_nat_range;

struct nf_nat_protocol
{
        /* Protocol number. */
        unsigned int protonum;

        struct module *me;

        /* Translate a packet to the target according to manip type.
           Return true if succeeded. */
        bool (*manip_pkt)(struct sk_buff *skb,
                          unsigned int iphdroff,
                          const struct nf_conntrack_tuple *tuple,
                          enum nf_nat_manip_type maniptype);

        /* Is the manipable part of the tuple between min and max incl? */
        bool (*in_range)(const struct nf_conntrack_tuple *tuple,
                         enum nf_nat_manip_type maniptype,
                         const union nf_conntrack_man_proto *min,
                         const union nf_conntrack_man_proto *max);

        /* Alter the per-proto part of the tuple (depending on
           maniptype), to give a unique tuple in the given range if
           possible; return false if not.  Per-protocol part of tuple
           is initialized to the incoming packet. */
        bool (*unique_tuple)(struct nf_conntrack_tuple *tuple,
                             const struct nf_nat_range *range,
                             enum nf_nat_manip_type maniptype,
                             const struct nf_conn *ct);

        int (*range_to_nlattr)(struct sk_buff *skb,
                               const struct nf_nat_range *range);

        int (*nlattr_to_range)(struct nlattr *tb[],
                               struct nf_nat_range *range);
};

/* Protocol registration. */
extern int nf_nat_protocol_register(const struct nf_nat_protocol *proto);
extern void nf_nat_protocol_unregister(const struct nf_nat_protocol *proto);

extern const struct nf_nat_protocol *nf_nat_proto_find_get(u_int8_t protocol);
extern void nf_nat_proto_put(const struct nf_nat_protocol *proto);

/* Built-in protocols. */
extern const struct nf_nat_protocol nf_nat_protocol_tcp;
extern const struct nf_nat_protocol nf_nat_protocol_udp;
extern const struct nf_nat_protocol nf_nat_protocol_icmp;
extern const struct nf_nat_protocol nf_nat_unknown_protocol;

extern int init_protocols(void) __init;
extern void cleanup_protocols(void);
extern const struct nf_nat_protocol *find_nat_proto(u_int16_t protonum);

extern bool nf_nat_proto_in_range(const struct nf_conntrack_tuple *tuple,
                                  enum nf_nat_manip_type maniptype,
                                  const union nf_conntrack_man_proto *min,
                                  const union nf_conntrack_man_proto *max);

extern bool nf_nat_proto_unique_tuple(struct nf_conntrack_tuple *tuple,
                                      const struct nf_nat_range *range,
                                      enum nf_nat_manip_type maniptype,
                                      const struct nf_conn *ct,
                                      u_int16_t *rover);

extern int nf_nat_proto_range_to_nlattr(struct sk_buff *skb,
                                        const struct nf_nat_range *range);
extern int nf_nat_proto_nlattr_to_range(struct nlattr *tb[],
                                        struct nf_nat_range *range);

#endif /*_NF_NAT_PROTO_H*/