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
7struct nf_nat_range;
8struct nf_nat_l3proto;
9
10struct 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. */
45int nf_nat_l4proto_register(u8 l3proto, const struct nf_nat_l4proto *l4proto);
46void nf_nat_l4proto_unregister(u8 l3proto,
47			       const struct nf_nat_l4proto *l4proto);
48
49const struct nf_nat_l4proto *__nf_nat_l4proto_find(u8 l3proto, u8 l4proto);
50
51/* Built-in protocols. */
52extern const struct nf_nat_l4proto nf_nat_l4proto_tcp;
53extern const struct nf_nat_l4proto nf_nat_l4proto_udp;
54extern const struct nf_nat_l4proto nf_nat_l4proto_icmp;
55extern const struct nf_nat_l4proto nf_nat_l4proto_icmpv6;
56extern const struct nf_nat_l4proto nf_nat_l4proto_unknown;
57
58bool nf_nat_l4proto_in_range(const struct nf_conntrack_tuple *tuple,
59			     enum nf_nat_manip_type maniptype,
60			     const union nf_conntrack_man_proto *min,
61			     const union nf_conntrack_man_proto *max);
62
63void nf_nat_l4proto_unique_tuple(const struct nf_nat_l3proto *l3proto,
64				 struct nf_conntrack_tuple *tuple,
65				 const struct nf_nat_range *range,
66				 enum nf_nat_manip_type maniptype,
67				 const struct nf_conn *ct, u16 *rover);
68
69int nf_nat_l4proto_nlattr_to_range(struct nlattr *tb[],
70				   struct nf_nat_range *range);
71
72#endif /*_NF_NAT_L4PROTO_H*/
73