1#ifndef _NF_NAT_HELPER_H
2#define _NF_NAT_HELPER_H
3/* NAT protocol helper routines. */
4
5#include <net/netfilter/nf_conntrack.h>
6
7struct sk_buff;
8
9/* These return true or false. */
10extern int __nf_nat_mangle_tcp_packet(struct sk_buff *skb,
11				      struct nf_conn *ct,
12				      enum ip_conntrack_info ctinfo,
13				      unsigned int match_offset,
14				      unsigned int match_len,
15				      const char *rep_buffer,
16				      unsigned int rep_len, bool adjust);
17
18static inline int nf_nat_mangle_tcp_packet(struct sk_buff *skb,
19					   struct nf_conn *ct,
20					   enum ip_conntrack_info ctinfo,
21					   unsigned int match_offset,
22					   unsigned int match_len,
23					   const char *rep_buffer,
24					   unsigned int rep_len)
25{
26	return __nf_nat_mangle_tcp_packet(skb, ct, ctinfo,
27					  match_offset, match_len,
28					  rep_buffer, rep_len, true);
29}
30
31extern int nf_nat_mangle_udp_packet(struct sk_buff *skb,
32				    struct nf_conn *ct,
33				    enum ip_conntrack_info ctinfo,
34				    unsigned int match_offset,
35				    unsigned int match_len,
36				    const char *rep_buffer,
37				    unsigned int rep_len);
38
39extern void nf_nat_set_seq_adjust(struct nf_conn *ct,
40				  enum ip_conntrack_info ctinfo,
41				  __be32 seq, s16 off);
42extern int nf_nat_seq_adjust(struct sk_buff *skb,
43			     struct nf_conn *ct,
44			     enum ip_conntrack_info ctinfo);
45extern int (*nf_nat_seq_adjust_hook)(struct sk_buff *skb,
46				     struct nf_conn *ct,
47				     enum ip_conntrack_info ctinfo);
48
49/* Setup NAT on this expected conntrack so it follows master, but goes
50 * to port ct->master->saved_proto. */
51extern void nf_nat_follow_master(struct nf_conn *ct,
52				 struct nf_conntrack_expect *this);
53
54extern s16 nf_nat_get_offset(const struct nf_conn *ct,
55			     enum ip_conntrack_dir dir,
56			     u32 seq);
57#endif
58