/* SCTP kernel reference Implementation
* (C) Copyright IBM Corp. 2001, 2004
* Copyright (c) 1999-2000 Cisco, Inc.
* Copyright (c) 1999-2001 Motorola, Inc.
* Copyright (c) 2001 Intel Corp.
* Copyright (c) 2001 Nokia, Inc.
* Copyright (c) 2001 La Monte H.P. Yarroll
*
* This file is part of the SCTP kernel reference Implementation
*
* Various protocol defined structures.
*
* This SCTP implementation 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, or (at your option)
* any later version.
*
* This SCTP implementation is distributed in the hope that it
* will be useful, but WITHOUT ANY WARRANTY; without even the implied
* ************************
* warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
* See the GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with GNU CC; see the file COPYING. If not, see
* .
*
* Please send any bug reports or fixes you make to the
* email address(es):
* lksctp developers
*
* Or submit a bug report through the following website:
* http://www.sf.net/projects/lksctp
*
* Written or modified by:
* La Monte H.P. Yarroll
* Karl Knutson
* Jon Grimm
* Xingang Guo
* randall@sctp.chicago.il.us
* kmorneau@cisco.com
* qxie1@email.mot.com
* Sridhar Samudrala
* Kevin Gao
*
* Any bugs reported given to us we will try to fix... any fixes shared will
* be incorporated into the next SCTP release.
*/
#ifndef __LINUX_SCTP_H__
#define __LINUX_SCTP_H__
#include /* We need in_addr. */
#include /* We need in6_addr. */
#include
#include
/* Section 3.1. SCTP Common Header Format */
typedef struct sctphdr {
__be16 source;
__be16 dest;
__be32 vtag;
__le32 checksum;
} __packed sctp_sctphdr_t;
static inline struct sctphdr *sctp_hdr(const struct sk_buff *skb)
{
return (struct sctphdr *)skb_transport_header(skb);
}
/* Section 3.2. Chunk Field Descriptions. */
typedef struct sctp_chunkhdr {
__u8 type;
__u8 flags;
__be16 length;
} __packed sctp_chunkhdr_t;
/* Section 3.2. Chunk Type Values.
* [Chunk Type] identifies the type of information contained in the Chunk
* Value field. It takes a value from 0 to 254. The value of 255 is
* reserved for future use as an extension field.
*/
typedef enum {
SCTP_CID_DATA = 0,
SCTP_CID_INIT = 1,
SCTP_CID_INIT_ACK = 2,
SCTP_CID_SACK = 3,
SCTP_CID_HEARTBEAT = 4,
SCTP_CID_HEARTBEAT_ACK = 5,
SCTP_CID_ABORT = 6,
SCTP_CID_SHUTDOWN = 7,
SCTP_CID_SHUTDOWN_ACK = 8,
SCTP_CID_ERROR = 9,
SCTP_CID_COOKIE_ECHO = 10,
SCTP_CID_COOKIE_ACK = 11,
SCTP_CID_ECN_ECNE = 12,
SCTP_CID_ECN_CWR = 13,
SCTP_CID_SHUTDOWN_COMPLETE = 14,
/* AUTH Extension Section 4.1 */
SCTP_CID_AUTH = 0x0F,
/* PR-SCTP Sec 3.2 */
SCTP_CID_FWD_TSN = 0xC0,
/* Use hex, as defined in ADDIP sec. 3.1 */
SCTP_CID_ASCONF = 0xC1,
SCTP_CID_ASCONF_ACK = 0x80,
} sctp_cid_t; /* enum */
/* Section 3.2
* Chunk Types are encoded such that the highest-order two bits specify
* the action that must be taken if the processing endpoint does not
* recognize the Chunk Type.
*/
typedef enum {
SCTP_CID_ACTION_DISCARD = 0x00,
SCTP_CID_ACTION_DISCARD_ERR = 0x40,
SCTP_CID_ACTION_SKIP = 0x80,
SCTP_CID_ACTION_SKIP_ERR = 0xc0,
} sctp_cid_action_t;
enum { SCTP_CID_ACTION_MASK = 0xc0, };
/* This flag is used in Chunk Flags for ABORT and SHUTDOWN COMPLETE.
*
* 3.3.7 Abort Association (ABORT) (6):
* The T bit is set to 0 if the sender had a TCB that it destroyed.
* If the sender did not have a TCB it should set this bit to 1.
*/
enum { SCTP_CHUNK_FLAG_T = 0x01 };
/*
* Set the T bit
*
* 0 1 2 3
* 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
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Type = 14 |Reserved |T| Length = 4 |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
*
* Chunk Flags: 8 bits
*
* Reserved: 7 bits
* Set to 0 on transmit and ignored on receipt.
*
* T bit: 1 bit
* The T bit is set to 0 if the sender had a TCB that it destroyed. If
* the sender did NOT have a TCB it should set this bit to 1.
*
* Note: Special rules apply to this chunk for verification, please
* see Section 8.5.1 for details.
*/
#define sctp_test_T_bit(c) ((c)->chunk_hdr->flags & SCTP_CHUNK_FLAG_T)
/* RFC 2960
* Section 3.2.1 Optional/Variable-length Parmaeter Format.
*/
typedef struct sctp_paramhdr {
__be16 type;
__be16 length;
} __packed sctp_paramhdr_t;
typedef enum {
/* RFC 2960 Section 3.3.5 */
SCTP_PARAM_HEARTBEAT_INFO = cpu_to_be16(1),
/* RFC 2960 Section 3.3.2.1 */
SCTP_PARAM_IPV4_ADDRESS = cpu_to_be16(5),
SCTP_PARAM_IPV6_ADDRESS = cpu_to_be16(6),
SCTP_PARAM_STATE_COOKIE = cpu_to_be16(7),
SCTP_PARAM_UNRECOGNIZED_PARAMETERS = cpu_to_be16(8),
SCTP_PARAM_COOKIE_PRESERVATIVE = cpu_to_be16(9),
SCTP_PARAM_HOST_NAME_ADDRESS = cpu_to_be16(11),
SCTP_PARAM_SUPPORTED_ADDRESS_TYPES = cpu_to_be16(12),
SCTP_PARAM_ECN_CAPABLE = cpu_to_be16(0x8000),
/* AUTH Extension Section 3 */
SCTP_PARAM_RANDOM = cpu_to_be16(0x8002),
SCTP_PARAM_CHUNKS = cpu_to_be16(0x8003),
SCTP_PARAM_HMAC_ALGO = cpu_to_be16(0x8004),
/* Add-IP: Supported Extensions, Section 4.2 */
SCTP_PARAM_SUPPORTED_EXT = cpu_to_be16(0x8008),
/* PR-SCTP Sec 3.1 */
SCTP_PARAM_FWD_TSN_SUPPORT = cpu_to_be16(0xc000),
/* Add-IP Extension. Section 3.2 */
SCTP_PARAM_ADD_IP = cpu_to_be16(0xc001),
SCTP_PARAM_DEL_IP = cpu_to_be16(0xc002),
SCTP_PARAM_ERR_CAUSE = cpu_to_be16(0xc003),
SCTP_PARAM_SET_PRIMARY = cpu_to_be16(0xc004),
SCTP_PARAM_SUCCESS_REPORT = cpu_to_be16(0xc005),
SCTP_PARAM_ADAPTATION_LAYER_IND = cpu_to_be16(0xc006),
} sctp_param_t; /* enum */
/* RFC 2960 Section 3.2.1
* The Parameter Types are encoded such that the highest-order two bits
* specify the action that must be taken if the processing endpoint does
* not recognize the Parameter Type.
*
*/
typedef enum {
SCTP_PARAM_ACTION_DISCARD = cpu_to_be16(0x0000),
SCTP_PARAM_ACTION_DISCARD_ERR = cpu_to_be16(0x4000),
SCTP_PARAM_ACTION_SKIP = cpu_to_be16(0x8000),
SCTP_PARAM_ACTION_SKIP_ERR = cpu_to_be16(0xc000),
} sctp_param_action_t;
enum { SCTP_PARAM_ACTION_MASK = cpu_to_be16(0xc000), };
/* RFC 2960 Section 3.3.1 Payload Data (DATA) (0) */
typedef struct sctp_datahdr {
__be32 tsn;
__be16 stream;
__be16 ssn;
__be32 ppid;
__u8 payload[0];
} __packed sctp_datahdr_t;
typedef struct sctp_data_chunk {
sctp_chunkhdr_t chunk_hdr;
sctp_datahdr_t data_hdr;
} __packed sctp_data_chunk_t;
/* DATA Chuck Specific Flags */
enum {
SCTP_DATA_MIDDLE_FRAG = 0x00,
SCTP_DATA_LAST_FRAG = 0x01,
SCTP_DATA_FIRST_FRAG = 0x02,
SCTP_DATA_NOT_FRAG = 0x03,
SCTP_DATA_UNORDERED = 0x04,
SCTP_DATA_SACK_IMM = 0x08,
};
enum { SCTP_DATA_FRAG_MASK = 0x03, };
/* RFC 2960 Section 3.3.2 Initiation (INIT) (1)
*
* This chunk is used to initiate a SCTP association between two
* endpoints.
*/
typedef struct sctp_inithdr {
__be32 init_tag;
__be32 a_rwnd;
__be16 num_outbound_streams;
__be16 num_inbound_streams;
__be32 initial_tsn;
__u8 params[0];
} __packed sctp_inithdr_t;
typedef struct sctp_init_chunk {
sctp_chunkhdr_t chunk_hdr;
sctp_inithdr_t init_hdr;
} __packed sctp_init_chunk_t;
/* Section 3.3.2.1. IPv4 Address Parameter (5) */
typedef struct sctp_ipv4addr_param {
sctp_paramhdr_t param_hdr;
struct in_addr addr;
} __packed sctp_ipv4addr_param_t;
/* Section 3.3.2.1. IPv6 Address Parameter (6) */
typedef struct sctp_ipv6addr_param {
sctp_paramhdr_t param_hdr;
struct in6_addr addr;
} __packed sctp_ipv6addr_param_t;
/* Section 3.3.2.1 Cookie Preservative (9) */
typedef struct sctp_cookie_preserve_param {
sctp_paramhdr_t param_hdr;
__be32 lifespan_increment;
} __packed sctp_cookie_preserve_param_t;
/* Section 3.3.2.1 Host Name Address (11) */
typedef struct sctp_hostname_param {
sctp_paramhdr_t param_hdr;
uint8_t hostname[0];
} __packed sctp_hostname_param_t;
/* Section 3.3.2.1 Supported Address Types (12) */
typedef struct sctp_supported_addrs_param {
sctp_paramhdr_t param_hdr;
__be16 types[0];
} __packed sctp_supported_addrs_param_t;
/* Appendix A. ECN Capable (32768) */
typedef struct sctp_ecn_capable_param {
sctp_paramhdr_t param_hdr;
} __packed sctp_ecn_capable_param_t;
/* ADDIP Section 3.2.6 Adaptation Layer Indication */
typedef struct sctp_adaptation_ind_param {
struct sctp_paramhdr param_hdr;
__be32 adaptation_ind;
} __packed sctp_adaptation_ind_param_t;
/* ADDIP Section 4.2.7 Supported Extensions Parameter */
typedef struct sctp_supported_ext_param {
struct sctp_paramhdr param_hdr;
__u8 chunks[0];
} __packed sctp_supported_ext_param_t;
/* AUTH Section 3.1 Random */
typedef struct sctp_random_param {
sctp_paramhdr_t param_hdr;
__u8 random_val[0];
} __packed sctp_random_param_t;
/* AUTH Section 3.2 Chunk List */
typedef struct sctp_chunks_param {
sctp_paramhdr_t param_hdr;
__u8 chunks[0];
} __packed sctp_chunks_param_t;
/* AUTH Section 3.3 HMAC Algorithm */
typedef struct sctp_hmac_algo_param {
sctp_paramhdr_t param_hdr;
__be16 hmac_ids[0];
} __packed sctp_hmac_algo_param_t;
/* RFC 2960. Section 3.3.3 Initiation Acknowledgement (INIT ACK) (2):
* The INIT ACK chunk is used to acknowledge the initiation of an SCTP
* association.
*/
typedef sctp_init_chunk_t sctp_initack_chunk_t;
/* Section 3.3.3.1 State Cookie (7) */
typedef struct sctp_cookie_param {
sctp_paramhdr_t p;
__u8 body[0];
} __packed sctp_cookie_param_t;
/* Section 3.3.3.1 Unrecognized Parameters (8) */
typedef struct sctp_unrecognized_param {
sctp_paramhdr_t param_hdr;
sctp_paramhdr_t unrecognized;
} __packed sctp_unrecognized_param_t;
/*
* 3.3.4 Selective Acknowledgement (SACK) (3):
*
* This chunk is sent to the peer endpoint to acknowledge received DATA
* chunks and to inform the peer endpoint of gaps in the received
* subsequences of DATA chunks as represented by their TSNs.
*/
typedef struct sctp_gap_ack_block {
__be16 start;
__be16 end;
} __packed sctp_gap_ack_block_t;
typedef __be32 sctp_dup_tsn_t;
typedef union {
sctp_gap_ack_block_t gab;
sctp_dup_tsn_t dup;
} sctp_sack_variable_t;
typedef struct sctp_sackhdr {
__be32 cum_tsn_ack;
__be32 a_rwnd;
__be16 num_gap_ack_blocks;
__be16 num_dup_tsns;
sctp_sack_variable_t variable[0];
} __packed sctp_sackhdr_t;
typedef struct sctp_sack_chunk {
sctp_chunkhdr_t chunk_hdr;
sctp_sackhdr_t sack_hdr;
} __packed sctp_sack_chunk_t;
/* RFC 2960. Section 3.3.5 Heartbeat Request (HEARTBEAT) (4):
*
* An endpoint should send this chunk to its peer endpoint to probe the
* reachability of a particular destination transport address defined in
* the present association.
*/
typedef struct sctp_heartbeathdr {
sctp_paramhdr_t info;
} __packed sctp_heartbeathdr_t;
typedef struct sctp_heartbeat_chunk {
sctp_chunkhdr_t chunk_hdr;
sctp_heartbeathdr_t hb_hdr;
} __packed sctp_heartbeat_chunk_t;
/* For the abort and shutdown ACK we must carry the init tag in the
* common header. Just the common header is all that is needed with a
* chunk descriptor.
*/
typedef struct sctp_abort_chunk {
sctp_chunkhdr_t uh;
} __packed sctp_abort_chunk_t;
/* For the graceful shutdown we must carry the tag (in common header)
* and the highest consecutive acking value.
*/
typedef struct sctp_shutdownhdr {
__be32 cum_tsn_ack;
} __packed sctp_shutdownhdr_t;
struct sctp_shutdown_chunk_t {
sctp_chunkhdr_t chunk_hdr;
sctp_shutdownhdr_t shutdown_hdr;
} __packed;
/* RFC 2960. Section 3.3.10 Operation Error (ERROR) (9) */
typedef struct sctp_errhdr {
__be16 cause;
__be16 length;
__u8 variable[0];
} __packed sctp_errhdr_t;
typedef struct sctp_operr_chunk {
sctp_chunkhdr_t chunk_hdr;
sctp_errhdr_t err_hdr;
} __packed sctp_operr_chunk_t;
/* RFC 2960 3.3.10 - Operation Error
*
* Cause Code: 16 bits (unsigned integer)
*
* Defines the type of error conditions being reported.
* Cause Code
* Value Cause Code
* --------- ----------------
* 1 Invalid Stream Identifier
* 2 Missing Mandatory Parameter
* 3 Stale Cookie Error
* 4 Out of Resource
* 5 Unresolvable Address
* 6 Unrecognized Chunk Type
* 7 Invalid Mandatory Parameter
* 8 Unrecognized Parameters
* 9 No User Data
* 10 Cookie Received While Shutting Down
*/
typedef enum {
SCTP_ERROR_NO_ERROR = cpu_to_be16(0x00),
SCTP_ERROR_INV_STRM = cpu_to_be16(0x01),
SCTP_ERROR_MISS_PARAM = cpu_to_be16(0x02),
SCTP_ERROR_STALE_COOKIE = cpu_to_be16(0x03),
SCTP_ERROR_NO_RESOURCE = cpu_to_be16(0x04),
SCTP_ERROR_DNS_FAILED = cpu_to_be16(0x05),
SCTP_ERROR_UNKNOWN_CHUNK = cpu_to_be16(0x06),
SCTP_ERROR_INV_PARAM = cpu_to_be16(0x07),
SCTP_ERROR_UNKNOWN_PARAM = cpu_to_be16(0x08),
SCTP_ERROR_NO_DATA = cpu_to_be16(0x09),
SCTP_ERROR_COOKIE_IN_SHUTDOWN = cpu_to_be16(0x0a),
/* SCTP Implementation Guide:
* 11 Restart of an association with new addresses
* 12 User Initiated Abort
* 13 Protocol Violation
*/
SCTP_ERROR_RESTART = cpu_to_be16(0x0b),
SCTP_ERROR_USER_ABORT = cpu_to_be16(0x0c),
SCTP_ERROR_PROTO_VIOLATION = cpu_to_be16(0x0d),
/* ADDIP Section 3.3 New Error Causes
*
* Four new Error Causes are added to the SCTP Operational Errors,
* primarily for use in the ASCONF-ACK chunk.
*
* Value Cause Code
* --------- ----------------
* 0x00A0 Request to Delete Last Remaining IP Address.
* 0x00A1 Operation Refused Due to Resource Shortage.
* 0x00A2 Request to Delete Source IP Address.
* 0x00A3 Association Aborted due to illegal ASCONF-ACK
* 0x00A4 Request refused - no authorization.
*/
SCTP_ERROR_DEL_LAST_IP = cpu_to_be16(0x00A0),
SCTP_ERROR_RSRC_LOW = cpu_to_be16(0x00A1),
SCTP_ERROR_DEL_SRC_IP = cpu_to_be16(0x00A2),
SCTP_ERROR_ASCONF_ACK = cpu_to_be16(0x00A3),
SCTP_ERROR_REQ_REFUSED = cpu_to_be16(0x00A4),
/* AUTH Section 4. New Error Cause
*
* This section defines a new error cause that will be sent if an AUTH
* chunk is received with an unsupported HMAC identifier.
* illustrates the new error cause.
*
* Cause Code Error Cause Name
* --------------------------------------------------------------
* 0x0105 Unsupported HMAC Identifier
*/
SCTP_ERROR_UNSUP_HMAC = cpu_to_be16(0x0105)
} sctp_error_t;
/* RFC 2960. Appendix A. Explicit Congestion Notification.
* Explicit Congestion Notification Echo (ECNE) (12)
*/
typedef struct sctp_ecnehdr {
__be32 lowest_tsn;
} sctp_ecnehdr_t;
typedef struct sctp_ecne_chunk {
sctp_chunkhdr_t chunk_hdr;
sctp_ecnehdr_t ence_hdr;
} __packed sctp_ecne_chunk_t;
/* RFC 2960. Appendix A. Explicit Congestion Notification.
* Congestion Window Reduced (CWR) (13)
*/
typedef struct sctp_cwrhdr {
__be32 lowest_tsn;
} sctp_cwrhdr_t;
typedef struct sctp_cwr_chunk {
sctp_chunkhdr_t chunk_hdr;
sctp_cwrhdr_t cwr_hdr;
} __packed sctp_cwr_chunk_t;
/* PR-SCTP
* 3.2 Forward Cumulative TSN Chunk Definition (FORWARD TSN)
*
* Forward Cumulative TSN chunk has the following format:
*
* 0 1 2 3
* 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
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Type = 192 | Flags = 0x00 | Length = Variable |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | New Cumulative TSN |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Stream-1 | Stream Sequence-1 |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* \ /
* / \
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Stream-N | Stream Sequence-N |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
*
* Chunk Flags:
*
* Set to all zeros on transmit and ignored on receipt.
*
* New Cumulative TSN: 32 bit u_int
*
* This indicates the new cumulative TSN to the data receiver. Upon
* the reception of this value, the data receiver MUST consider
* any missing TSNs earlier than or equal to this value as received
* and stop reporting them as gaps in any subsequent SACKs.
*
* Stream-N: 16 bit u_int
*
* This field holds a stream number that was skipped by this
* FWD-TSN.
*
* Stream Sequence-N: 16 bit u_int
* This field holds the sequence number associated with the stream
* that was skipped. The stream sequence field holds the largest stream
* sequence number in this stream being skipped. The receiver of
* the FWD-TSN's can use the Stream-N and Stream Sequence-N fields
* to enable delivery of any stranded TSN's that remain on the stream
* re-ordering queues. This field MUST NOT report TSN's corresponding
* to DATA chunk that are marked as unordered. For ordered DATA
* chunks this field MUST be filled in.
*/
struct sctp_fwdtsn_skip {
__be16 stream;
__be16 ssn;
} __packed;
struct sctp_fwdtsn_hdr {
__be32 new_cum_tsn;
struct sctp_fwdtsn_skip skip[0];
} __packed;
struct sctp_fwdtsn_chunk {
struct sctp_chunkhdr chunk_hdr;
struct sctp_fwdtsn_hdr fwdtsn_hdr;
} __packed;
/* ADDIP
* Section 3.1.1 Address Configuration Change Chunk (ASCONF)
*
* Serial Number: 32 bits (unsigned integer)
* This value represents a Serial Number for the ASCONF Chunk. The
* valid range of Serial Number is from 0 to 2^32-1.
* Serial Numbers wrap back to 0 after reaching 2^32 -1.
*
* Address Parameter: 8 or 20 bytes (depending on type)
* The address is an address of the sender of the ASCONF chunk,
* the address MUST be considered part of the association by the
* peer endpoint. This field may be used by the receiver of the
* ASCONF to help in finding the association. This parameter MUST
* be present in every ASCONF message i.e. it is a mandatory TLV
* parameter.
*
* ASCONF Parameter: TLV format
* Each Address configuration change is represented by a TLV
* parameter as defined in Section 3.2. One or more requests may
* be present in an ASCONF Chunk.
*
* Section 3.1.2 Address Configuration Acknowledgement Chunk (ASCONF-ACK)
*
* Serial Number: 32 bits (unsigned integer)
* This value represents the Serial Number for the received ASCONF
* Chunk that is acknowledged by this chunk. This value is copied
* from the received ASCONF Chunk.
*
* ASCONF Parameter Response: TLV format
* The ASCONF Parameter Response is used in the ASCONF-ACK to
* report status of ASCONF processing.
*/
typedef struct sctp_addip_param {
sctp_paramhdr_t param_hdr;
__be32 crr_id;
} __packed sctp_addip_param_t;
typedef struct sctp_addiphdr {
__be32 serial;
__u8 params[0];
} __packed sctp_addiphdr_t;
typedef struct sctp_addip_chunk {
sctp_chunkhdr_t chunk_hdr;
sctp_addiphdr_t addip_hdr;
} __packed sctp_addip_chunk_t;
/* AUTH
* Section 4.1 Authentication Chunk (AUTH)
*
* This chunk is used to hold the result of the HMAC calculation.
*
* 0 1 2 3
* 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
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Type = 0x0F | Flags=0 | Length |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Shared Key Identifier | HMAC Identifier |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | |
* \ HMAC /
* / \
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
*
* Type: 1 byte (unsigned integer)
* This value MUST be set to 0x0F for all AUTH-chunks.
*
* Flags: 1 byte (unsigned integer)
* Set to zero on transmit and ignored on receipt.
*
* Length: 2 bytes (unsigned integer)
* This value holds the length of the HMAC in bytes plus 8.
*
* Shared Key Identifier: 2 bytes (unsigned integer)
* This value describes which endpoint pair shared key is used.
*
* HMAC Identifier: 2 bytes (unsigned integer)
* This value describes which message digest is being used. Table 2
* shows the currently defined values.
*
* The following Table 2 shows the currently defined values for HMAC
* identifiers.
*
* +-----------------+--------------------------+
* | HMAC Identifier | Message Digest Algorithm |
* +-----------------+--------------------------+
* | 0 | Reserved |
* | 1 | SHA-1 defined in [8] |
* | 2 | Reserved |
* | 3 | SHA-256 defined in [8] |
* +-----------------+--------------------------+
*
*
* HMAC: n bytes (unsigned integer) This hold the result of the HMAC
* calculation.
*/
typedef struct sctp_authhdr {
__be16 shkey_id;
__be16 hmac_id;
__u8 hmac[0];
} __packed sctp_authhdr_t;
typedef struct sctp_auth_chunk {
sctp_chunkhdr_t chunk_hdr;
sctp_authhdr_t auth_hdr;
} __packed sctp_auth_chunk_t;
#endif /* __LINUX_SCTP_H__ */