include/net/netfilter/nf_nat_helper.h

   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
   7 struct sk_buff;
   8
   9 /* These return true or false. */
  10 extern int __nf_nat_mangle_tcp_packet(struct sk_buff *skb,
  11                                       struct nf_conn *ct,
  12                                       enum ip_conntrack_info ctinfo,
  13                                       unsigned int protoff,
  14                                       unsigned int match_offset,
  15                                       unsigned int match_len,
  16                                       const char *rep_buffer,
  17                                       unsigned int rep_len, bool adjust);
  18
  19 static inline int nf_nat_mangle_tcp_packet(struct sk_buff *skb,
  20                                            struct nf_conn *ct,
  21                                            enum ip_conntrack_info ctinfo,
  22                                            unsigned int protoff,
  23                                            unsigned int match_offset,
  24                                            unsigned int match_len,
  25                                            const char *rep_buffer,
  26                                            unsigned int rep_len)
  27 {
  28         return __nf_nat_mangle_tcp_packet(skb, ct, ctinfo, protoff,
  29                                           match_offset, match_len,
  30                                           rep_buffer, rep_len, true);
  31 }
  32
  33 extern int nf_nat_mangle_udp_packet(struct sk_buff *skb,
  34                                     struct nf_conn *ct,
  35                                     enum ip_conntrack_info ctinfo,
  36                                     unsigned int protoff,
  37                                     unsigned int match_offset,
  38                                     unsigned int match_len,
  39                                     const char *rep_buffer,
  40                                     unsigned int rep_len);
  41
  42 extern void nf_nat_set_seq_adjust(struct nf_conn *ct,
  43                                   enum ip_conntrack_info ctinfo,
  44                                   __be32 seq, s16 off);
  45 extern int nf_nat_seq_adjust(struct sk_buff *skb,
  46                              struct nf_conn *ct,
  47                              enum ip_conntrack_info ctinfo,
  48                              unsigned int protoff);
  49 extern int (*nf_nat_seq_adjust_hook)(struct sk_buff *skb,
  50                                      struct nf_conn *ct,
  51                                      enum ip_conntrack_info ctinfo,
  52                                      unsigned int protoff);
  53
  54 /* Setup NAT on this expected conntrack so it follows master, but goes
  55  * to port ct->master->saved_proto. */
  56 extern void nf_nat_follow_master(struct nf_conn *ct,
  57                                  struct nf_conntrack_expect *this);
  58
  59 extern s16 nf_nat_get_offset(const struct nf_conn *ct,
  60                              enum ip_conntrack_dir dir,
  61                              u32 seq);
  62
  63 extern void nf_nat_tcp_seq_adjust(struct sk_buff *skb, struct nf_conn *ct,
  64                                   u32 dir, int off);
  65
  66 #endif