xref: /linux/include/uapi/linux/seg6_iptunnel.h (revision 71e2f4dd5a65bd8dbca0b77661e75eea471168f8)
1 /* SPDX-License-Identifier: GPL-2.0+ WITH Linux-syscall-note */
2 /*
3  *  SR-IPv6 implementation
4  *
5  *  Author:
6  *  David Lebrun <david.lebrun@uclouvain.be>
7  *
8  *
9  *  This program is free software; you can redistribute it and/or
10  *      modify it under the terms of the GNU General Public License
11  *      as published by the Free Software Foundation; either version
12  *      2 of the License, or (at your option) any later version.
13  */
14 
15 #ifndef _UAPI_LINUX_SEG6_IPTUNNEL_H
16 #define _UAPI_LINUX_SEG6_IPTUNNEL_H
17 
18 #include <linux/seg6.h>		/* For struct ipv6_sr_hdr. */
19 
20 enum {
21 	SEG6_IPTUNNEL_UNSPEC,
22 	SEG6_IPTUNNEL_SRH,
23 	__SEG6_IPTUNNEL_MAX,
24 };
25 #define SEG6_IPTUNNEL_MAX (__SEG6_IPTUNNEL_MAX - 1)
26 
27 struct seg6_iptunnel_encap {
28 	int mode;
29 	struct ipv6_sr_hdr srh[0];
30 };
31 
32 #define SEG6_IPTUN_ENCAP_SIZE(x) ((sizeof(*x)) + (((x)->srh->hdrlen + 1) << 3))
33 
34 enum {
35 	SEG6_IPTUN_MODE_INLINE,
36 	SEG6_IPTUN_MODE_ENCAP,
37 	SEG6_IPTUN_MODE_L2ENCAP,
38 };
39 
40 #ifdef __KERNEL__
41 
42 static inline size_t seg6_lwt_headroom(struct seg6_iptunnel_encap *tuninfo)
43 {
44 	int head = 0;
45 
46 	switch (tuninfo->mode) {
47 	case SEG6_IPTUN_MODE_INLINE:
48 		break;
49 	case SEG6_IPTUN_MODE_ENCAP:
50 		head = sizeof(struct ipv6hdr);
51 		break;
52 	case SEG6_IPTUN_MODE_L2ENCAP:
53 		return 0;
54 	}
55 
56 	return ((tuninfo->srh->hdrlen + 1) << 3) + head;
57 }
58 
59 #endif
60 
61 #endif
62