/* SPDX-License-Identifier: GPL-2.0-or-later */

  /* 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.
   *

   * Please send any bug reports or fixes you make to the
   * email address(es):

   *    lksctp developers <linux-sctp@vger.kernel.org>

   *
   * Or submit a bug report through the following website:
   *    http://www.sf.net/projects/lksctp
   *
   * Written or modified by:
   *    La Monte H.P. Yarroll <piggy@acm.org>
   *    Karl Knutson <karl@athena.chicago.il.us>
   *    Jon Grimm <jgrimm@us.ibm.com>
   *    Xingang Guo <xingang.guo@intel.com>
   *    randall@sctp.chicago.il.us
   *    kmorneau@cisco.com
   *    qxie1@email.mot.com
   *    Sridhar Samudrala <sri@us.ibm.com>
   *    Kevin Gao <kevin.gao@intel.com>
   *
   * 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 <linux/in.h>		/* We need in_addr.  */
  #include <linux/in6.h>		/* We need in6_addr.  */

  #include <linux/skbuff.h>

  #include <uapi/linux/sctp.h>

  
  /* Section 3.1.  SCTP Common Header Format */

  struct sctphdr {

  	__be16 source;
  	__be16 dest;
  	__be32 vtag;

  	__le32 checksum;

  };

  static inline struct sctphdr *sctp_hdr(const struct sk_buff *skb)
  {

  	return (struct sctphdr *)skb_transport_header(skb);

  }

  /* Section 3.2.  Chunk Field Descriptions. */

  struct sctp_chunkhdr {

  	__u8 type;
  	__u8 flags;

  	__be16 length;

  };

  
  
  /* 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.
   */

  enum sctp_cid {

  	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,

  	/* sctp ndata 5.1. I-DATA */
  	SCTP_CID_I_DATA			= 0x40,

  	/* 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_I_FWD_TSN		= 0xC2,

  	SCTP_CID_ASCONF_ACK		= 0x80,

  	SCTP_CID_RECONF			= 0x82,

  }; /* 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.
   */

  enum {

  	SCTP_CID_ACTION_DISCARD     = 0x00,
  	SCTP_CID_ACTION_DISCARD_ERR = 0x40,
  	SCTP_CID_ACTION_SKIP        = 0x80,
  	SCTP_CID_ACTION_SKIP_ERR    = 0xc0,

  };

  
  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.
   */

  struct sctp_paramhdr {

  	__be16 type;
  	__be16 length;

  };

  enum sctp_param {

  
  	/* 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),

  	/* RE-CONFIG. Section 4 */
  	SCTP_PARAM_RESET_OUT_REQUEST		= cpu_to_be16(0x000d),
  	SCTP_PARAM_RESET_IN_REQUEST		= cpu_to_be16(0x000e),
  	SCTP_PARAM_RESET_TSN_REQUEST		= cpu_to_be16(0x000f),
  	SCTP_PARAM_RESET_RESPONSE		= cpu_to_be16(0x0010),
  	SCTP_PARAM_RESET_ADD_OUT_STREAMS	= cpu_to_be16(0x0011),
  	SCTP_PARAM_RESET_ADD_IN_STREAMS		= cpu_to_be16(0x0012),

  }; /* 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.
   *
   */

  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),

  };

  enum { SCTP_PARAM_ACTION_MASK = cpu_to_be16(0xc000), };

  
  /* RFC 2960 Section 3.3.1 Payload Data (DATA) (0) */

  struct sctp_datahdr {

  	__be32 tsn;
  	__be16 stream;
  	__be16 ssn;

  	__u32 ppid;

  	__u8  payload[];

  };

  struct sctp_data_chunk {

  	struct sctp_chunkhdr chunk_hdr;

  	struct sctp_datahdr data_hdr;

  };

  struct sctp_idatahdr {
  	__be32 tsn;
  	__be16 stream;
  	__be16 reserved;
  	__be32 mid;
  	union {
  		__u32 ppid;
  		__be32 fsn;
  	};
  	__u8 payload[0];
  };
  
  struct sctp_idata_chunk {
  	struct sctp_chunkhdr chunk_hdr;
  	struct sctp_idatahdr data_hdr;
  };

  /* 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.
   */

  struct sctp_inithdr {

  	__be32 init_tag;
  	__be32 a_rwnd;
  	__be16 num_outbound_streams;
  	__be16 num_inbound_streams;
  	__be32 initial_tsn;

  	__u8  params[];

  };

  struct sctp_init_chunk {

  	struct sctp_chunkhdr chunk_hdr;

  	struct sctp_inithdr init_hdr;

  };

  
  
  /* Section 3.3.2.1. IPv4 Address Parameter (5) */

  struct sctp_ipv4addr_param {

  	struct sctp_paramhdr param_hdr;

  	struct in_addr addr;
  };

  
  /* Section 3.3.2.1. IPv6 Address Parameter (6) */

  struct sctp_ipv6addr_param {

  	struct sctp_paramhdr param_hdr;

  	struct in6_addr addr;

  };

  
  /* Section 3.3.2.1 Cookie Preservative (9) */

  struct sctp_cookie_preserve_param {

  	struct sctp_paramhdr param_hdr;

  	__be32 lifespan_increment;
  };

  
  /* Section 3.3.2.1 Host Name Address (11) */

  struct sctp_hostname_param {

  	struct sctp_paramhdr param_hdr;

  	uint8_t hostname[];

  };

  
  /* Section 3.3.2.1 Supported Address Types (12) */

  struct sctp_supported_addrs_param {

  	struct sctp_paramhdr param_hdr;

  	__be16 types[];

  };

  /* ADDIP Section 3.2.6 Adaptation Layer Indication */

  struct sctp_adaptation_ind_param {

  	struct sctp_paramhdr param_hdr;

  	__be32 adaptation_ind;

  };

  /* ADDIP Section 4.2.7 Supported Extensions Parameter */

  struct sctp_supported_ext_param {

  	struct sctp_paramhdr param_hdr;

  	__u8 chunks[];

  };

  /* AUTH Section 3.1 Random */

  struct sctp_random_param {

  	struct sctp_paramhdr param_hdr;

  	__u8 random_val[];

  };

  
  /* AUTH Section 3.2 Chunk List */

  struct sctp_chunks_param {

  	struct sctp_paramhdr param_hdr;

  	__u8 chunks[];

  };

  
  /* AUTH Section 3.3 HMAC Algorithm */

  struct sctp_hmac_algo_param {

  	struct sctp_paramhdr param_hdr;

  	__be16 hmac_ids[];

  };

  /* 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.
   */

  struct sctp_initack_chunk {
  	struct sctp_chunkhdr chunk_hdr;
  	struct sctp_inithdr init_hdr;
  };

  
  /* Section 3.3.3.1 State Cookie (7) */

  struct sctp_cookie_param {

  	struct sctp_paramhdr p;

  	__u8 body[];

  };

  
  /* Section 3.3.3.1 Unrecognized Parameters (8) */

  struct sctp_unrecognized_param {

  	struct sctp_paramhdr param_hdr;
  	struct sctp_paramhdr unrecognized;

  };

  
  
  
  /*
   * 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.
   */

  struct sctp_gap_ack_block {

  	__be16 start;
  	__be16 end;

  };

  union sctp_sack_variable {

  	struct sctp_gap_ack_block gab;

  	__be32 dup;

  };

  struct sctp_sackhdr {

  	__be32 cum_tsn_ack;
  	__be32 a_rwnd;
  	__be16 num_gap_ack_blocks;
  	__be16 num_dup_tsns;

  	union sctp_sack_variable variable[];

  };

  struct sctp_sack_chunk {

  	struct sctp_chunkhdr chunk_hdr;

  	struct sctp_sackhdr sack_hdr;

  };

  
  
  /* 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.
   */

  struct sctp_heartbeathdr {

  	struct sctp_paramhdr info;

  };

  struct sctp_heartbeat_chunk {

  	struct sctp_chunkhdr chunk_hdr;

  	struct sctp_heartbeathdr hb_hdr;

  };

  
  
  /* 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.
   */

  struct sctp_abort_chunk {

  	struct sctp_chunkhdr uh;

  };

  
  
  /* For the graceful shutdown we must carry the tag (in common header)
   * and the highest consecutive acking value.
   */

  struct sctp_shutdownhdr {

  	__be32 cum_tsn_ack;

  };

  struct sctp_shutdown_chunk {

  	struct sctp_chunkhdr chunk_hdr;

  	struct sctp_shutdownhdr shutdown_hdr;

  };

  
  /* RFC 2960.  Section 3.3.10 Operation Error (ERROR) (9) */

  struct sctp_errhdr {

  	__be16 cause;
  	__be16 length;

  	__u8  variable[];

  };

  struct sctp_operr_chunk {

  	struct sctp_chunkhdr chunk_hdr;

  	struct sctp_errhdr err_hdr;

  };

  
  /* 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
   */

  enum sctp_error {

  	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)

  };

  
  
  
  /* RFC 2960.  Appendix A.  Explicit Congestion Notification.
   *   Explicit Congestion Notification Echo (ECNE) (12)
   */

  struct sctp_ecnehdr {

  	__be32 lowest_tsn;

  };

  struct sctp_ecne_chunk {

  	struct sctp_chunkhdr chunk_hdr;

  	struct sctp_ecnehdr ence_hdr;

  };

  
  /* RFC 2960.  Appendix A.  Explicit Congestion Notification.
   *   Congestion Window Reduced (CWR) (13)
   */

  struct sctp_cwrhdr {

  	__be32 lowest_tsn;

  };

  /* 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;

  };

  
  struct sctp_fwdtsn_hdr {

  	__be32 new_cum_tsn;

  	struct sctp_fwdtsn_skip skip[];

  };

  
  struct sctp_fwdtsn_chunk {
  	struct sctp_chunkhdr chunk_hdr;
  	struct sctp_fwdtsn_hdr fwdtsn_hdr;

  };

  struct sctp_ifwdtsn_skip {
  	__be16 stream;
  	__u8 reserved;
  	__u8 flags;
  	__be32 mid;
  };
  
  struct sctp_ifwdtsn_hdr {
  	__be32 new_cum_tsn;

  	struct sctp_ifwdtsn_skip skip[];

  };
  
  struct sctp_ifwdtsn_chunk {
  	struct sctp_chunkhdr chunk_hdr;
  	struct sctp_ifwdtsn_hdr fwdtsn_hdr;
  };

  
  /* 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.
   */

  struct sctp_addip_param {
  	struct sctp_paramhdr param_hdr;
  	__be32 crr_id;
  };

  struct sctp_addiphdr {

  	__be32	serial;

  	__u8	params[];

  };

  struct sctp_addip_chunk {

  	struct sctp_chunkhdr chunk_hdr;

  	struct sctp_addiphdr addip_hdr;

  };

  /* 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.
   */

  struct sctp_authhdr {

  	__be16 shkey_id;
  	__be16 hmac_id;

  	__u8   hmac[];

  };

  struct sctp_auth_chunk {

  	struct sctp_chunkhdr chunk_hdr;

  	struct sctp_authhdr auth_hdr;

  };

  struct sctp_infox {
  	struct sctp_info *sctpinfo;
  	struct sctp_association *asoc;
  };

  struct sctp_reconf_chunk {

  	struct sctp_chunkhdr chunk_hdr;

  	__u8 params[];

  };

  
  struct sctp_strreset_outreq {

  	struct sctp_paramhdr param_hdr;

  	__be32 request_seq;
  	__be32 response_seq;
  	__be32 send_reset_at_tsn;

  	__be16 list_of_streams[];

  };

  
  struct sctp_strreset_inreq {

  	struct sctp_paramhdr param_hdr;

  	__be32 request_seq;

  	__be16 list_of_streams[];

  };

  struct sctp_strreset_tsnreq {

  	struct sctp_paramhdr param_hdr;

  	__be32 request_seq;

  };

  struct sctp_strreset_addstrm {

  	struct sctp_paramhdr param_hdr;

  	__be32 request_seq;
  	__be16 number_of_streams;
  	__be16 reserved;

  };

  enum {
  	SCTP_STRRESET_NOTHING_TO_DO	= 0x00,
  	SCTP_STRRESET_PERFORMED		= 0x01,
  	SCTP_STRRESET_DENIED		= 0x02,
  	SCTP_STRRESET_ERR_WRONG_SSN	= 0x03,
  	SCTP_STRRESET_ERR_IN_PROGRESS	= 0x04,
  	SCTP_STRRESET_ERR_BAD_SEQNO	= 0x05,
  	SCTP_STRRESET_IN_PROGRESS	= 0x06,
  };
  
  struct sctp_strreset_resp {

  	struct sctp_paramhdr param_hdr;

  	__be32 response_seq;
  	__be32 result;

  };
  
  struct sctp_strreset_resptsn {

  	struct sctp_paramhdr param_hdr;

  	__be32 response_seq;
  	__be32 result;
  	__be32 senders_next_tsn;
  	__be32 receivers_next_tsn;

  };

  enum {
  	SCTP_DSCP_SET_MASK = 0x1,
  	SCTP_DSCP_VAL_MASK = 0xfc,
  	SCTP_FLOWLABEL_SET_MASK = 0x100000,
  	SCTP_FLOWLABEL_VAL_MASK = 0xfffff
  };

  #endif /* __LINUX_SCTP_H__ */