include/net/netfilter/nf_nat_protocol.h

   1 /* Header for use in defining a given protocol. */
   2 #ifndef _NF_NAT_PROTOCOL_H
   3 #define _NF_NAT_PROTOCOL_H
   4 #include <net/netfilter/nf_nat.h>
   5 #include <linux/netfilter/nfnetlink_conntrack.h>
   6
   7 struct nf_nat_ipv4_range;
   8
   9 struct nf_nat_protocol {
  10         /* Protocol number. */
  11         unsigned int protonum;
  12
  13         /* Translate a packet to the target according to manip type.
  14            Return true if succeeded. */
  15         bool (*manip_pkt)(struct sk_buff *skb,
  16                           unsigned int iphdroff,
  17                           const struct nf_conntrack_tuple *tuple,
  18                           enum nf_nat_manip_type maniptype);
  19
  20         /* Is the manipable part of the tuple between min and max incl? */
  21         bool (*in_range)(const struct nf_conntrack_tuple *tuple,
  22                          enum nf_nat_manip_type maniptype,
  23                          const union nf_conntrack_man_proto *min,
  24                          const union nf_conntrack_man_proto *max);
  25
  26         /* Alter the per-proto part of the tuple (depending on
  27            maniptype), to give a unique tuple in the given range if
  28            possible.  Per-protocol part of tuple is initialized to the
  29            incoming packet. */
  30         void (*unique_tuple)(struct nf_conntrack_tuple *tuple,
  31                              const struct nf_nat_ipv4_range *range,
  32                              enum nf_nat_manip_type maniptype,
  33                              const struct nf_conn *ct);
  34
  35         int (*nlattr_to_range)(struct nlattr *tb[],
  36                                struct nf_nat_ipv4_range *range);
  37 };
  38
  39 /* Protocol registration. */
  40 extern int nf_nat_protocol_register(const struct nf_nat_protocol *proto);
  41 extern void nf_nat_protocol_unregister(const struct nf_nat_protocol *proto);
  42
  43 /* Built-in protocols. */
  44 extern const struct nf_nat_protocol nf_nat_protocol_tcp;
  45 extern const struct nf_nat_protocol nf_nat_protocol_udp;
  46 extern const struct nf_nat_protocol nf_nat_protocol_icmp;
  47 extern const struct nf_nat_protocol nf_nat_unknown_protocol;
  48
  49 extern int init_protocols(void) __init;
  50 extern void cleanup_protocols(void);
  51 extern const struct nf_nat_protocol *find_nat_proto(u_int16_t protonum);
  52
  53 extern bool nf_nat_proto_in_range(const struct nf_conntrack_tuple *tuple,
  54                                   enum nf_nat_manip_type maniptype,
  55                                   const union nf_conntrack_man_proto *min,
  56                                   const union nf_conntrack_man_proto *max);
  57
  58 extern void nf_nat_proto_unique_tuple(struct nf_conntrack_tuple *tuple,
  59                                       const struct nf_nat_ipv4_range *range,
  60                                       enum nf_nat_manip_type maniptype,
  61                                       const struct nf_conn *ct,
  62                                       u_int16_t *rover);
  63
  64 extern int nf_nat_proto_nlattr_to_range(struct nlattr *tb[],
  65                                         struct nf_nat_ipv4_range *range);
  66
  67 #endif /*_NF_NAT_PROTO_H*/