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Vector Packet Processing
sr_packet.h
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#ifndef included_vnet_sr_packet_h
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#define included_vnet_sr_packet_h
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#include <
vnet/ip/ip.h
>
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/*
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* ipv6 segment-routing header format
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*
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* Copyright (c) 2013 Cisco and/or its affiliates.
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at:
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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/*
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* The Segment Routing Header (SRH) is defined as follows:
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*
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* 0 1 2 3
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* 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
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* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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* | Next Header | Hdr Ext Len | Routing Type | Segments Left |
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* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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* | Last Entry | Flags | Tag |
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* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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* | |
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* | Segment List[0] (128 bits IPv6 address) |
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* | |
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* | |
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* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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* | |
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* | |
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* ...
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* | |
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* | |
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* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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* | |
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* | Segment List[n] (128 bits IPv6 address) |
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* | |
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* | |
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* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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* // //
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* // Optional Type Length Value objects (variable) //
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* // //
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* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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*
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* where:
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*
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* o Next Header: 8-bit selector. Identifies the type of header
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* immediately following the SRH.
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*
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* o Hdr Ext Len: 8-bit unsigned integer, is the length of the SRH
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* header in 8-octet units, not including the first 8 octets.
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*
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* o Routing Type: TBD, to be assigned by IANA (suggested value: 4).
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*
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* o Segments Left. Defined in [RFC8200], it contains the index, in
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* the Segment List, of the next segment to inspect. Segments Left
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* is decremented at each segment.
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*
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* o Last Entry: contains the index (zero based), in the Segment List,
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* of the the last element of the Segment List
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*
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* o Flags: 8 bits of flags. Following flags are defined:
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*
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* 0 1 2 3 4 5 6 7
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* +-+-+-+-+-+-+-+-+
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* |U|P|O|A|H| U |
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* +-+-+-+-+-+-+-+-+
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*
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* U: Unused and for future use. SHOULD be unset on transmission
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* and MUST be ignored on receipt.
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*
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* P-flag: Protected flag. Set when the packet has been rerouted
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* through FRR mechanism by an SR endpoint node.
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*
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* O-flag: OAM flag. When set, it indicates that this packet is
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* an operations and management (OAM) packet.
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*
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* A-flag: Alert flag. If present, it means important Type Length
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* Value (TLV) objects are present. See Section 3.1 for details
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* on TLVs objects.
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*
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* H-flag: HMAC flag. If set, the HMAC TLV is present and is
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* encoded as the last TLV of the SRH. In other words, the last
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* 36 octets of the SRH represent the HMAC information. See
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* Section 3.1.5 for details on the HMAC TLV.
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*
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* o Tag: tag a packet as part of a class or group of packets, e.g.,
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* packets sharing the same set of properties. When tag is not used
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* at source it MUST be set to zero on transmission. When tag is not
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* used during SRH Processing it SHOULD be ignored.
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*
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* o Segment List[n]: 128 bit IPv6 addresses representing the nth
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* segment in the Segment List. The Segment List is encoded starting
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* from the last segment of the path. I.e., the first element of the
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* segment list (Segment List [0]) contains the last segment of the
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* path while the last segment of the Segment List (Segment List[n])
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* contains the first segment of the path. The index contained in
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* "Segments Left" identifies the current active segment.
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*
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* o Type Length Value (TLV) are described in Section 3.1.
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*
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*/
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#ifndef IPPROTO_IPV6_ROUTE
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#define IPPROTO_IPV6_ROUTE 43
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#endif
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#define ROUTING_HEADER_TYPE_SR 4
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typedef
struct
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{
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/* Protocol for next header. */
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u8
protocol
;
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/*
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* Length of routing header in 8 octet units,
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* not including the first 8 octets
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*/
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u8
length
;
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/* Type of routing header; type 4 = segement routing */
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u8
type
;
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/* Next segment in the segment list */
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u8
segments_left
;
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/* Pointer to the first segment in the header */
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u8
last_entry
;
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/* Flag bits */
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#define IP6_SR_HEADER_FLAG_PROTECTED (0x40)
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#define IP6_SR_HEADER_FLAG_OAM (0x20)
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#define IP6_SR_HEADER_FLAG_ALERT (0x10)
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#define IP6_SR_HEADER_FLAG_HMAC (0x80)
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/* values 0x0, 0x4 - 0x7 are reserved */
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u8
flags
;
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u16
tag
;
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/* The segment elts */
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ip6_address_t
segments[0];
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} __attribute__ ((packed))
ip6_sr_header_t
;
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/*
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* fd.io coding-style-patch-verification: ON
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*
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* Local Variables:
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* eval: (c-set-style "gnu")
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* End:
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*/
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#endif
/* included_vnet_sr_packet_h */
ip6_sr_header_t::segments_left
u8 segments_left
Definition:
sr_packet.h:133
ip6_sr_header_t::last_entry
u8 last_entry
Definition:
sr_packet.h:136
ip.h
u8
unsigned char u8
Definition:
types.h:56
ip6_sr_header_t::tag
u16 tag
Definition:
sr_packet.h:146
ip6_sr_header_t::protocol
u8 protocol
Definition:
sr_packet.h:122
ip6_sr_header_t::type
u8 type
Definition:
sr_packet.h:130
u16
unsigned short u16
Definition:
types.h:57
ip6_sr_header_t::flags
u8 flags
Definition:
sr_packet.h:145
ip6_sr_header_t
Definition:
sr_packet.h:119
ip6_sr_header_t::length
u8 length
Definition:
sr_packet.h:127
ip6_address_t
Definition:
ip6_packet.h:46
src
vnet
srv6
sr_packet.h
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