include/net/netfilter/nf_nat_l4proto.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 /* Header for use in defining a given protocol. */
   3 #ifndef _NF_NAT_L4PROTO_H
   4 #define _NF_NAT_L4PROTO_H
   5 #include <net/netfilter/nf_nat.h>
   6 #include <linux/netfilter/nfnetlink_conntrack.h>
   7
   8 struct nf_nat_range;
   9 struct nf_nat_l3proto;
  10
  11 struct nf_nat_l4proto {
  12         /* Protocol number. */
  13         u8 l4proto;
  14
  15         /* Translate a packet to the target according to manip type.
  16          * Return true if succeeded.
  17          */
  18         bool (*manip_pkt)(struct sk_buff *skb,
  19                           const struct nf_nat_l3proto *l3proto,
  20                           unsigned int iphdroff, unsigned int hdroff,
  21                           const struct nf_conntrack_tuple *tuple,
  22                           enum nf_nat_manip_type maniptype);
  23
  24         /* Is the manipable part of the tuple between min and max incl? */
  25         bool (*in_range)(const struct nf_conntrack_tuple *tuple,
  26                          enum nf_nat_manip_type maniptype,
  27                          const union nf_conntrack_man_proto *min,
  28                          const union nf_conntrack_man_proto *max);
  29
  30         /* Alter the per-proto part of the tuple (depending on
  31          * maniptype), to give a unique tuple in the given range if
  32          * possible.  Per-protocol part of tuple is initialized to the
  33          * incoming packet.
  34          */
  35         void (*unique_tuple)(const struct nf_nat_l3proto *l3proto,
  36                              struct nf_conntrack_tuple *tuple,
  37                              const struct nf_nat_range *range,
  38                              enum nf_nat_manip_type maniptype,
  39                              const struct nf_conn *ct);
  40
  41         int (*nlattr_to_range)(struct nlattr *tb[],
  42                                struct nf_nat_range *range);
  43 };
  44
  45 /* Protocol registration. */
  46 int nf_nat_l4proto_register(u8 l3proto, const struct nf_nat_l4proto *l4proto);
  47 void nf_nat_l4proto_unregister(u8 l3proto,
  48                                const struct nf_nat_l4proto *l4proto);
  49
  50 const struct nf_nat_l4proto *__nf_nat_l4proto_find(u8 l3proto, u8 l4proto);
  51
  52 /* Built-in protocols. */
  53 extern const struct nf_nat_l4proto nf_nat_l4proto_tcp;
  54 extern const struct nf_nat_l4proto nf_nat_l4proto_udp;
  55 extern const struct nf_nat_l4proto nf_nat_l4proto_icmp;
  56 extern const struct nf_nat_l4proto nf_nat_l4proto_icmpv6;
  57 extern const struct nf_nat_l4proto nf_nat_l4proto_unknown;
  58 #ifdef CONFIG_NF_NAT_PROTO_DCCP
  59 extern const struct nf_nat_l4proto nf_nat_l4proto_dccp;
  60 #endif
  61 #ifdef CONFIG_NF_NAT_PROTO_SCTP
  62 extern const struct nf_nat_l4proto nf_nat_l4proto_sctp;
  63 #endif
  64 #ifdef CONFIG_NF_NAT_PROTO_UDPLITE
  65 extern const struct nf_nat_l4proto nf_nat_l4proto_udplite;
  66 #endif
  67
  68 bool nf_nat_l4proto_in_range(const struct nf_conntrack_tuple *tuple,
  69                              enum nf_nat_manip_type maniptype,
  70                              const union nf_conntrack_man_proto *min,
  71                              const union nf_conntrack_man_proto *max);
  72
  73 void nf_nat_l4proto_unique_tuple(const struct nf_nat_l3proto *l3proto,
  74                                  struct nf_conntrack_tuple *tuple,
  75                                  const struct nf_nat_range *range,
  76                                  enum nf_nat_manip_type maniptype,
  77                                  const struct nf_conn *ct, u16 *rover);
  78
  79 int nf_nat_l4proto_nlattr_to_range(struct nlattr *tb[],
  80                                    struct nf_nat_range *range);
  81
  82 #endif /*_NF_NAT_L4PROTO_H*/