include/net/netfilter/nf_nat_l4proto.h

   1 /* Header for use in defining a given protocol. */
   2 #ifndef _NF_NAT_L4PROTO_H
   3 #define _NF_NAT_L4PROTO_H
   4 #include <net/netfilter/nf_nat.h>
   5 #include <linux/netfilter/nfnetlink_conntrack.h>
   6
   7 struct nf_nat_range;
   8 struct nf_nat_l3proto;
   9
  10 struct nf_nat_l4proto {
  11         /* Protocol number. */
  12         u8 l4proto;
  13
  14         /* Translate a packet to the target according to manip type.
  15          * Return true if succeeded.
  16          */
  17         bool (*manip_pkt)(struct sk_buff *skb,
  18                           const struct nf_nat_l3proto *l3proto,
  19                           unsigned int iphdroff, unsigned int hdroff,
  20                           const struct nf_conntrack_tuple *tuple,
  21                           enum nf_nat_manip_type maniptype);
  22
  23         /* Is the manipable part of the tuple between min and max incl? */
  24         bool (*in_range)(const struct nf_conntrack_tuple *tuple,
  25                          enum nf_nat_manip_type maniptype,
  26                          const union nf_conntrack_man_proto *min,
  27                          const union nf_conntrack_man_proto *max);
  28
  29         /* Alter the per-proto part of the tuple (depending on
  30          * maniptype), to give a unique tuple in the given range if
  31          * possible.  Per-protocol part of tuple is initialized to the
  32          * incoming packet.
  33          */
  34         void (*unique_tuple)(const struct nf_nat_l3proto *l3proto,
  35                              struct nf_conntrack_tuple *tuple,
  36                              const struct nf_nat_range *range,
  37                              enum nf_nat_manip_type maniptype,
  38                              const struct nf_conn *ct);
  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_l4proto_register(u8 l3proto, const struct nf_nat_l4proto *l4proto);
  46 extern void nf_nat_l4proto_unregister(u8 l3proto, const struct nf_nat_l4proto *l4proto);
  47
  48 extern const struct nf_nat_l4proto *__nf_nat_l4proto_find(u8 l3proto, u8 l4proto);
  49
  50 /* Built-in protocols. */
  51 extern const struct nf_nat_l4proto nf_nat_l4proto_tcp;
  52 extern const struct nf_nat_l4proto nf_nat_l4proto_udp;
  53 extern const struct nf_nat_l4proto nf_nat_l4proto_icmp;
  54 extern const struct nf_nat_l4proto nf_nat_l4proto_unknown;
  55
  56 extern bool nf_nat_l4proto_in_range(const struct nf_conntrack_tuple *tuple,
  57                                     enum nf_nat_manip_type maniptype,
  58                                     const union nf_conntrack_man_proto *min,
  59                                     const union nf_conntrack_man_proto *max);
  60
  61 extern void nf_nat_l4proto_unique_tuple(const struct nf_nat_l3proto *l3proto,
  62                                         struct nf_conntrack_tuple *tuple,
  63                                         const struct nf_nat_range *range,
  64                                         enum nf_nat_manip_type maniptype,
  65                                         const struct nf_conn *ct,
  66                                         u16 *rover);
  67
  68 extern int nf_nat_l4proto_nlattr_to_range(struct nlattr *tb[],
  69                                           struct nf_nat_range *range);
  70
  71 #endif /*_NF_NAT_L4PROTO_H*/