netfilter: add IPv6 segment routing header 'srh' match

It allows matching packets based on Segment Routing Header
(SRH) information.
The implementation considers revision 7 of the SRH draft.
https://tools.ietf.org/html/draft-ietf-6man-segment-routing-header-07

Currently supported match options include:
(1) Next Header
(2) Hdr Ext Len
(3) Segments Left
(4) Last Entry
(5) Tag value of SRH

Signed-off-by: Ahmed Abdelsalam <amsalam20@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This commit is contained in:
Ahmed Abdelsalam
2018-01-07 19:22:02 +01:00
committed by Pablo Neira Ayuso
parent cbef426ce7
commit 202a8ff545
4 changed files with 228 additions and 0 deletions

View File

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/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
#ifndef _IP6T_SRH_H
#define _IP6T_SRH_H
#include <linux/types.h>
#include <linux/netfilter.h>
/* Values for "mt_flags" field in struct ip6t_srh */
#define IP6T_SRH_NEXTHDR 0x0001
#define IP6T_SRH_LEN_EQ 0x0002
#define IP6T_SRH_LEN_GT 0x0004
#define IP6T_SRH_LEN_LT 0x0008
#define IP6T_SRH_SEGS_EQ 0x0010
#define IP6T_SRH_SEGS_GT 0x0020
#define IP6T_SRH_SEGS_LT 0x0040
#define IP6T_SRH_LAST_EQ 0x0080
#define IP6T_SRH_LAST_GT 0x0100
#define IP6T_SRH_LAST_LT 0x0200
#define IP6T_SRH_TAG 0x0400
#define IP6T_SRH_MASK 0x07FF
/* Values for "mt_invflags" field in struct ip6t_srh */
#define IP6T_SRH_INV_NEXTHDR 0x0001
#define IP6T_SRH_INV_LEN_EQ 0x0002
#define IP6T_SRH_INV_LEN_GT 0x0004
#define IP6T_SRH_INV_LEN_LT 0x0008
#define IP6T_SRH_INV_SEGS_EQ 0x0010
#define IP6T_SRH_INV_SEGS_GT 0x0020
#define IP6T_SRH_INV_SEGS_LT 0x0040
#define IP6T_SRH_INV_LAST_EQ 0x0080
#define IP6T_SRH_INV_LAST_GT 0x0100
#define IP6T_SRH_INV_LAST_LT 0x0200
#define IP6T_SRH_INV_TAG 0x0400
#define IP6T_SRH_INV_MASK 0x07FF
/**
* struct ip6t_srh - SRH match options
* @ next_hdr: Next header field of SRH
* @ hdr_len: Extension header length field of SRH
* @ segs_left: Segments left field of SRH
* @ last_entry: Last entry field of SRH
* @ tag: Tag field of SRH
* @ mt_flags: match options
* @ mt_invflags: Invert the sense of match options
*/
struct ip6t_srh {
__u8 next_hdr;
__u8 hdr_len;
__u8 segs_left;
__u8 last_entry;
__u16 tag;
__u16 mt_flags;
__u16 mt_invflags;
};
#endif /*_IP6T_SRH_H*/