linux_dsm_epyc7002/include/uapi/linux/seg6_iptunnel.h
David Lebrun 6c8702c60b ipv6: sr: add support for SRH encapsulation and injection with lwtunnels
This patch creates a new type of interfaceless lightweight tunnel (SEG6),
enabling the encapsulation and injection of SRH within locally emitted
packets and forwarded packets.

>From a configuration viewpoint, a seg6 tunnel would be configured as follows:

  ip -6 ro ad fc00::1/128 encap seg6 mode encap segs fc42::1,fc42::2,fc42::3 dev eth0

Any packet whose destination address is fc00::1 would thus be encapsulated
within an outer IPv6 header containing the SRH with three segments, and would
actually be routed to the first segment of the list. If `mode inline' was
specified instead of `mode encap', then the SRH would be directly inserted
after the IPv6 header without outer encapsulation.

The inline mode is only available if CONFIG_IPV6_SEG6_INLINE is enabled. This
feature was made configurable because direct header insertion may break
several mechanisms such as PMTUD or IPSec AH.

Signed-off-by: David Lebrun <david.lebrun@uclouvain.be>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-09 20:40:06 -05:00

45 lines
1013 B
C

/*
* SR-IPv6 implementation
*
* Author:
* David Lebrun <david.lebrun@uclouvain.be>
*
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#ifndef _UAPI_LINUX_SEG6_IPTUNNEL_H
#define _UAPI_LINUX_SEG6_IPTUNNEL_H
enum {
SEG6_IPTUNNEL_UNSPEC,
SEG6_IPTUNNEL_SRH,
__SEG6_IPTUNNEL_MAX,
};
#define SEG6_IPTUNNEL_MAX (__SEG6_IPTUNNEL_MAX - 1)
struct seg6_iptunnel_encap {
int mode;
struct ipv6_sr_hdr srh[0];
};
#define SEG6_IPTUN_ENCAP_SIZE(x) ((sizeof(*x)) + (((x)->srh->hdrlen + 1) << 3))
enum {
SEG6_IPTUN_MODE_INLINE,
SEG6_IPTUN_MODE_ENCAP,
};
static inline size_t seg6_lwt_headroom(struct seg6_iptunnel_encap *tuninfo)
{
int encap = (tuninfo->mode == SEG6_IPTUN_MODE_ENCAP);
return ((tuninfo->srh->hdrlen + 1) << 3) +
(encap * sizeof(struct ipv6hdr));
}
#endif