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_range;
   8
   9 struct nf_nat_protocol {
  10         /* Protocol number. */
  11         unsigned int protonum;
  12
  13         struct module *me;
  14
  15         /* Translate a packet to the target according to manip type.
  16            Return true if succeeded. */
  17         bool (*manip_pkt)(struct sk_buff *skb,
  18                           unsigned int iphdroff,
  19                           const struct nf_conntrack_tuple *tuple,
  20                           enum nf_nat_manip_type maniptype);
  21
  22         /* Is the manipable part of the tuple between min and max incl? */
  23         bool (*in_range)(const struct nf_conntrack_tuple *tuple,
  24                          enum nf_nat_manip_type maniptype,
  25                          const union nf_conntrack_man_proto *min,
  26                          const union nf_conntrack_man_proto *max);
  27
  28         /* Alter the per-proto part of the tuple (depending on
  29            maniptype), to give a unique tuple in the given range if
  30            possible; return false if not.  Per-protocol part of tuple
  31            is initialized to the incoming packet. */
  32         bool (*unique_tuple)(struct nf_conntrack_tuple *tuple,
  33                              const struct nf_nat_range *range,
  34                              enum nf_nat_manip_type maniptype,
  35                              const struct nf_conn *ct);
  36
  37         int (*range_to_nlattr)(struct sk_buff *skb,
  38                                const struct nf_nat_range *range);
  39
  40         int (*nlattr_to_range)(struct nlattr *tb[],
  41                                struct nf_nat_range *range);
  42 };
  43
  44 /* Protocol registration. */
  45 extern int nf_nat_protocol_register(const struct nf_nat_protocol *proto);
  46 extern void nf_nat_protocol_unregister(const struct nf_nat_protocol *proto);
  47
  48 extern const struct nf_nat_protocol *nf_nat_proto_find_get(u_int8_t protocol);
  49 extern void nf_nat_proto_put(const struct nf_nat_protocol *proto);
  50
  51 /* Built-in protocols. */
  52 extern const struct nf_nat_protocol nf_nat_protocol_tcp;
  53 extern const struct nf_nat_protocol nf_nat_protocol_udp;
  54 extern const struct nf_nat_protocol nf_nat_protocol_icmp;
  55 extern const struct nf_nat_protocol nf_nat_unknown_protocol;
  56
  57 extern int init_protocols(void) __init;
  58 extern void cleanup_protocols(void);
  59 extern const struct nf_nat_protocol *find_nat_proto(u_int16_t protonum);
  60
  61 extern bool nf_nat_proto_in_range(const struct nf_conntrack_tuple *tuple,
  62                                   enum nf_nat_manip_type maniptype,
  63                                   const union nf_conntrack_man_proto *min,
  64                                   const union nf_conntrack_man_proto *max);
  65
  66 extern bool nf_nat_proto_unique_tuple(struct nf_conntrack_tuple *tuple,
  67                                       const struct nf_nat_range *range,
  68                                       enum nf_nat_manip_type maniptype,
  69                                       const struct nf_conn *ct,
  70                                       u_int16_t *rover);
  71
  72 extern int nf_nat_proto_range_to_nlattr(struct sk_buff *skb,
  73                                         const struct nf_nat_range *range);
  74 extern int nf_nat_proto_nlattr_to_range(struct nlattr *tb[],
  75                                         struct nf_nat_range *range);
  76
  77 #endif /*_NF_NAT_PROTO_H*/