include/net/gre.h

   1 #ifndef __LINUX_GRE_H
   2 #define __LINUX_GRE_H
   3
   4 #include <linux/skbuff.h>
   5 #include <net/ip_tunnels.h>
   6
   7 #define GREPROTO_CISCO          0
   8 #define GREPROTO_PPTP           1
   9 #define GREPROTO_MAX            2
  10
  11 struct gre_protocol {
  12         int  (*handler)(struct sk_buff *skb);
  13         void (*err_handler)(struct sk_buff *skb, u32 info);
  14 };
  15
  16 struct gre_base_hdr {
  17         __be16 flags;
  18         __be16 protocol;
  19 };
  20 #define GRE_HEADER_SECTION 4
  21
  22 int gre_add_protocol(const struct gre_protocol *proto, u8 version);
  23 int gre_del_protocol(const struct gre_protocol *proto, u8 version);
  24
  25 static inline __be16 gre_flags_to_tnl_flags(__be16 flags)
  26 {
  27         __be16 tflags = 0;
  28
  29         if (flags & GRE_CSUM)
  30                 tflags |= TUNNEL_CSUM;
  31         if (flags & GRE_ROUTING)
  32                 tflags |= TUNNEL_ROUTING;
  33         if (flags & GRE_KEY)
  34                 tflags |= TUNNEL_KEY;
  35         if (flags & GRE_SEQ)
  36                 tflags |= TUNNEL_SEQ;
  37         if (flags & GRE_STRICT)
  38                 tflags |= TUNNEL_STRICT;
  39         if (flags & GRE_REC)
  40                 tflags |= TUNNEL_REC;
  41         if (flags & GRE_VERSION)
  42                 tflags |= TUNNEL_VERSION;
  43
  44         return tflags;
  45 }
  46
  47 static inline __be16 tnl_flags_to_gre_flags(__be16 tflags)
  48 {
  49         __be16 flags = 0;
  50
  51         if (tflags & TUNNEL_CSUM)
  52                 flags |= GRE_CSUM;
  53         if (tflags & TUNNEL_ROUTING)
  54                 flags |= GRE_ROUTING;
  55         if (tflags & TUNNEL_KEY)
  56                 flags |= GRE_KEY;
  57         if (tflags & TUNNEL_SEQ)
  58                 flags |= GRE_SEQ;
  59         if (tflags & TUNNEL_STRICT)
  60                 flags |= GRE_STRICT;
  61         if (tflags & TUNNEL_REC)
  62                 flags |= GRE_REC;
  63         if (tflags & TUNNEL_VERSION)
  64                 flags |= GRE_VERSION;
  65
  66         return flags;
  67 }
  68
  69 #endif