From 1ababeba4a21f3dba3da3523c670b207fb2feb62 Mon Sep 17 00:00:00 2001 From: David Lebrun Date: Tue, 8 Nov 2016 14:57:39 +0100 Subject: ipv6: implement dataplane support for rthdr type 4 (Segment Routing Header) Implement minimal support for processing of SR-enabled packets as described in https://tools.ietf.org/html/draft-ietf-6man-segment-routing-header-02. This patch implements the following operations: - Intermediate segment endpoint: incrementation of active segment and rerouting. - Egress for SR-encapsulated packets: decapsulation of outer IPv6 header + SRH and routing of inner packet. - Cleanup flag support for SR-inlined packets: removal of SRH if we are the penultimate segment endpoint. A per-interface sysctl seg6_enabled is provided, to accept/deny SR-enabled packets. Default is deny. This patch does not provide support for HMAC-signed packets. Signed-off-by: David Lebrun Signed-off-by: David S. Miller --- include/linux/ipv6.h | 1 + include/linux/seg6.h | 6 ++++++ include/net/seg6.h | 36 +++++++++++++++++++++++++++++++ include/uapi/linux/ipv6.h | 2 ++ include/uapi/linux/seg6.h | 54 +++++++++++++++++++++++++++++++++++++++++++++++ 5 files changed, 99 insertions(+) create mode 100644 include/linux/seg6.h create mode 100644 include/net/seg6.h create mode 100644 include/uapi/linux/seg6.h (limited to 'include') diff --git a/include/linux/ipv6.h b/include/linux/ipv6.h index 1afb6e8d35c3..68d3f71f0abf 100644 --- a/include/linux/ipv6.h +++ b/include/linux/ipv6.h @@ -64,6 +64,7 @@ struct ipv6_devconf { } stable_secret; __s32 use_oif_addrs_only; __s32 keep_addr_on_down; + __s32 seg6_enabled; struct ctl_table_header *sysctl_header; }; diff --git a/include/linux/seg6.h b/include/linux/seg6.h new file mode 100644 index 000000000000..7a66d2b4c5a6 --- /dev/null +++ b/include/linux/seg6.h @@ -0,0 +1,6 @@ +#ifndef _LINUX_SEG6_H +#define _LINUX_SEG6_H + +#include + +#endif diff --git a/include/net/seg6.h b/include/net/seg6.h new file mode 100644 index 000000000000..4dd52a7e95f1 --- /dev/null +++ b/include/net/seg6.h @@ -0,0 +1,36 @@ +/* + * SR-IPv6 implementation + * + * Author: + * David Lebrun + * + * + * 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 _NET_SEG6_H +#define _NET_SEG6_H + +static inline void update_csum_diff4(struct sk_buff *skb, __be32 from, + __be32 to) +{ + __be32 diff[] = { ~from, to }; + + skb->csum = ~csum_partial((char *)diff, sizeof(diff), ~skb->csum); +} + +static inline void update_csum_diff16(struct sk_buff *skb, __be32 *from, + __be32 *to) +{ + __be32 diff[] = { + ~from[0], ~from[1], ~from[2], ~from[3], + to[0], to[1], to[2], to[3], + }; + + skb->csum = ~csum_partial((char *)diff, sizeof(diff), ~skb->csum); +} + +#endif diff --git a/include/uapi/linux/ipv6.h b/include/uapi/linux/ipv6.h index 8c2772340c3f..7ff1d654e333 100644 --- a/include/uapi/linux/ipv6.h +++ b/include/uapi/linux/ipv6.h @@ -39,6 +39,7 @@ struct in6_ifreq { #define IPV6_SRCRT_STRICT 0x01 /* Deprecated; will be removed */ #define IPV6_SRCRT_TYPE_0 0 /* Deprecated; will be removed */ #define IPV6_SRCRT_TYPE_2 2 /* IPv6 type 2 Routing Header */ +#define IPV6_SRCRT_TYPE_4 4 /* Segment Routing with IPv6 */ /* * routing header @@ -178,6 +179,7 @@ enum { DEVCONF_DROP_UNSOLICITED_NA, DEVCONF_KEEP_ADDR_ON_DOWN, DEVCONF_RTR_SOLICIT_MAX_INTERVAL, + DEVCONF_SEG6_ENABLED, DEVCONF_MAX }; diff --git a/include/uapi/linux/seg6.h b/include/uapi/linux/seg6.h new file mode 100644 index 000000000000..c396a8052f73 --- /dev/null +++ b/include/uapi/linux/seg6.h @@ -0,0 +1,54 @@ +/* + * SR-IPv6 implementation + * + * Author: + * David Lebrun + * + * + * 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_H +#define _UAPI_LINUX_SEG6_H + +/* + * SRH + */ +struct ipv6_sr_hdr { + __u8 nexthdr; + __u8 hdrlen; + __u8 type; + __u8 segments_left; + __u8 first_segment; + __u8 flag_1; + __u8 flag_2; + __u8 reserved; + + struct in6_addr segments[0]; +}; + +#define SR6_FLAG1_CLEANUP (1 << 7) +#define SR6_FLAG1_PROTECTED (1 << 6) +#define SR6_FLAG1_OAM (1 << 5) +#define SR6_FLAG1_ALERT (1 << 4) +#define SR6_FLAG1_HMAC (1 << 3) + +#define SR6_TLV_INGRESS 1 +#define SR6_TLV_EGRESS 2 +#define SR6_TLV_OPAQUE 3 +#define SR6_TLV_PADDING 4 +#define SR6_TLV_HMAC 5 + +#define sr_has_cleanup(srh) ((srh)->flag_1 & SR6_FLAG1_CLEANUP) +#define sr_has_hmac(srh) ((srh)->flag_1 & SR6_FLAG1_HMAC) + +struct sr6_tlv { + __u8 type; + __u8 len; + __u8 data[0]; +}; + +#endif -- cgit v1.2.3-70-g09d2