4 #include <linux/skbuff.h>
5 #include <net/ip_tunnels.h>
7 #define GREPROTO_CISCO 0
8 #define GREPROTO_PPTP 1
10 #define GRE_IP_PROTO_MAX 2
13 int (*handler)(struct sk_buff *skb);
14 void (*err_handler)(struct sk_buff *skb, u32 info);
21 #define GRE_HEADER_SECTION 4
23 int gre_add_protocol(const struct gre_protocol *proto, u8 version);
24 int gre_del_protocol(const struct gre_protocol *proto, u8 version);
26 struct gre_cisco_protocol {
27 int (*handler)(struct sk_buff *skb, const struct tnl_ptk_info *tpi);
28 int (*err_handler)(struct sk_buff *skb, u32 info,
29 const struct tnl_ptk_info *tpi);
33 int gre_cisco_register(struct gre_cisco_protocol *proto);
34 int gre_cisco_unregister(struct gre_cisco_protocol *proto);
35 void gre_build_header(struct sk_buff *skb, const struct tnl_ptk_info *tpi,
37 struct sk_buff *gre_handle_offloads(struct sk_buff *skb, bool gre_csum);
39 static inline int ip_gre_calc_hlen(__be16 o_flags)
43 if (o_flags&TUNNEL_CSUM)
45 if (o_flags&TUNNEL_KEY)
47 if (o_flags&TUNNEL_SEQ)
52 static inline __be16 gre_flags_to_tnl_flags(__be16 flags)
57 tflags |= TUNNEL_CSUM;
58 if (flags & GRE_ROUTING)
59 tflags |= TUNNEL_ROUTING;
64 if (flags & GRE_STRICT)
65 tflags |= TUNNEL_STRICT;
68 if (flags & GRE_VERSION)
69 tflags |= TUNNEL_VERSION;
74 static inline __be16 tnl_flags_to_gre_flags(__be16 tflags)
78 if (tflags & TUNNEL_CSUM)
80 if (tflags & TUNNEL_ROUTING)
82 if (tflags & TUNNEL_KEY)
84 if (tflags & TUNNEL_SEQ)
86 if (tflags & TUNNEL_STRICT)
88 if (tflags & TUNNEL_REC)
90 if (tflags & TUNNEL_VERSION)