Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
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#define GRE_IP_PROTO_MAX 2
11
12struct gre_protocol {
13 int (*handler)(struct sk_buff *skb);
14 void (*err_handler)(struct sk_buff *skb, u32 info);
15};
16
17struct gre_base_hdr {
18 __be16 flags;
19 __be16 protocol;
20};
21#define GRE_HEADER_SECTION 4
22
23int gre_add_protocol(const struct gre_protocol *proto, u8 version);
24int gre_del_protocol(const struct gre_protocol *proto, u8 version);
25
26struct 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);
30 u8 priority;
31};
32
33int gre_cisco_register(struct gre_cisco_protocol *proto);
34int gre_cisco_unregister(struct gre_cisco_protocol *proto);
35
36void gre_build_header(struct sk_buff *skb, const struct tnl_ptk_info *tpi,
37 int hdr_len);
38
39static inline struct sk_buff *gre_handle_offloads(struct sk_buff *skb,
40 bool gre_csum)
41{
42 return iptunnel_handle_offloads(skb, gre_csum, SKB_GSO_GRE);
43}
44
45
46static inline int ip_gre_calc_hlen(__be16 o_flags)
47{
48 int addend = 4;
49
50 if (o_flags&TUNNEL_CSUM)
51 addend += 4;
52 if (o_flags&TUNNEL_KEY)
53 addend += 4;
54 if (o_flags&TUNNEL_SEQ)
55 addend += 4;
56 return addend;
57}
58
59static inline __be16 gre_flags_to_tnl_flags(__be16 flags)
60{
61 __be16 tflags = 0;
62
63 if (flags & GRE_CSUM)
64 tflags |= TUNNEL_CSUM;
65 if (flags & GRE_ROUTING)
66 tflags |= TUNNEL_ROUTING;
67 if (flags & GRE_KEY)
68 tflags |= TUNNEL_KEY;
69 if (flags & GRE_SEQ)
70 tflags |= TUNNEL_SEQ;
71 if (flags & GRE_STRICT)
72 tflags |= TUNNEL_STRICT;
73 if (flags & GRE_REC)
74 tflags |= TUNNEL_REC;
75 if (flags & GRE_VERSION)
76 tflags |= TUNNEL_VERSION;
77
78 return tflags;
79}
80
81static inline __be16 tnl_flags_to_gre_flags(__be16 tflags)
82{
83 __be16 flags = 0;
84
85 if (tflags & TUNNEL_CSUM)
86 flags |= GRE_CSUM;
87 if (tflags & TUNNEL_ROUTING)
88 flags |= GRE_ROUTING;
89 if (tflags & TUNNEL_KEY)
90 flags |= GRE_KEY;
91 if (tflags & TUNNEL_SEQ)
92 flags |= GRE_SEQ;
93 if (tflags & TUNNEL_STRICT)
94 flags |= GRE_STRICT;
95 if (tflags & TUNNEL_REC)
96 flags |= GRE_REC;
97 if (tflags & TUNNEL_VERSION)
98 flags |= GRE_VERSION;
99
100 return flags;
101}
102
103#endif