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
36int gre_offload_init(void);
37void gre_offload_exit(void);
38
39void gre_build_header(struct sk_buff *skb, const struct tnl_ptk_info *tpi,
40 int hdr_len);
41
42static inline struct sk_buff *gre_handle_offloads(struct sk_buff *skb,
43 bool gre_csum)
44{
45 return iptunnel_handle_offloads(skb, gre_csum, SKB_GSO_GRE);
46}
47
48
49static inline int ip_gre_calc_hlen(__be16 o_flags)
50{
51 int addend = 4;
52
53 if (o_flags&TUNNEL_CSUM)
54 addend += 4;
55 if (o_flags&TUNNEL_KEY)
56 addend += 4;
57 if (o_flags&TUNNEL_SEQ)
58 addend += 4;
59 return addend;
60}
61
62static inline __be16 gre_flags_to_tnl_flags(__be16 flags)
63{
64 __be16 tflags = 0;
65
66 if (flags & GRE_CSUM)
67 tflags |= TUNNEL_CSUM;
68 if (flags & GRE_ROUTING)
69 tflags |= TUNNEL_ROUTING;
70 if (flags & GRE_KEY)
71 tflags |= TUNNEL_KEY;
72 if (flags & GRE_SEQ)
73 tflags |= TUNNEL_SEQ;
74 if (flags & GRE_STRICT)
75 tflags |= TUNNEL_STRICT;
76 if (flags & GRE_REC)
77 tflags |= TUNNEL_REC;
78 if (flags & GRE_VERSION)
79 tflags |= TUNNEL_VERSION;
80
81 return tflags;
82}
83
84static inline __be16 tnl_flags_to_gre_flags(__be16 tflags)
85{
86 __be16 flags = 0;
87
88 if (tflags & TUNNEL_CSUM)
89 flags |= GRE_CSUM;
90 if (tflags & TUNNEL_ROUTING)
91 flags |= GRE_ROUTING;
92 if (tflags & TUNNEL_KEY)
93 flags |= GRE_KEY;
94 if (tflags & TUNNEL_SEQ)
95 flags |= GRE_SEQ;
96 if (tflags & TUNNEL_STRICT)
97 flags |= GRE_STRICT;
98 if (tflags & TUNNEL_REC)
99 flags |= GRE_REC;
100 if (tflags & TUNNEL_VERSION)
101 flags |= GRE_VERSION;
102
103 return flags;
104}
105
106#endif