include/linux/sctp.h

   1 /* SCTP kernel reference Implementation
   2  * (C) Copyright IBM Corp. 2001, 2004
   3  * Copyright (c) 1999-2000 Cisco, Inc.
   4  * Copyright (c) 1999-2001 Motorola, Inc.
   5  * Copyright (c) 2001 Intel Corp.
   6  * Copyright (c) 2001 Nokia, Inc.
   7  * Copyright (c) 2001 La Monte H.P. Yarroll
   8  *
   9  * This file is part of the SCTP kernel reference Implementation
  10  *
  11  * Various protocol defined structures.
  12  *
  13  * The SCTP reference implementation is free software;
  14  * you can redistribute it and/or modify it under the terms of
  15  * the GNU General Public License as published by
  16  * the Free Software Foundation; either version 2, or (at your option)
  17  * any later version.
  18  *
  19  * The SCTP reference implementation is distributed in the hope that it
  20  * will be useful, but WITHOUT ANY WARRANTY; without even the implied
  21  *                 ************************
  22  * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  23  * See the GNU General Public License for more details.
  24  *
  25  * You should have received a copy of the GNU General Public License
  26  * along with GNU CC; see the file COPYING.  If not, write to
  27  * the Free Software Foundation, 59 Temple Place - Suite 330,
  28  * Boston, MA 02111-1307, USA.
  29  *
  30  * Please send any bug reports or fixes you make to the
  31  * email address(es):
  32  *    lksctp developers <lksctp-developerst@lists.sourceforge.net>
  33  *
  34  * Or submit a bug report through the following website:
  35  *    http://www.sf.net/projects/lksctp
  36  *
  37  * Written or modified by:
  38  *    La Monte H.P. Yarroll <piggy@acm.org>
  39  *    Karl Knutson <karl@athena.chicago.il.us>
  40  *    Jon Grimm <jgrimm@us.ibm.com>
  41  *    Xingang Guo <xingang.guo@intel.com>
  42  *    randall@sctp.chicago.il.us
  43  *    kmorneau@cisco.com
  44  *    qxie1@email.mot.com
  45  *    Sridhar Samudrala <sri@us.ibm.com>
  46  *    Kevin Gao <kevin.gao@intel.com>
  47  *
  48  * Any bugs reported given to us we will try to fix... any fixes shared will
  49  * be incorporated into the next SCTP release.
  50  */
  51 #ifndef __LINUX_SCTP_H__
  52 #define __LINUX_SCTP_H__
  53
  54 #include <linux/in.h>           /* We need in_addr.  */
  55 #include <linux/in6.h>          /* We need in6_addr.  */
  56
  57
  58 /* Section 3.1.  SCTP Common Header Format */
  59 typedef struct sctphdr {
  60         __u16 source;
  61         __u16 dest;
  62         __u32 vtag;
  63         __u32 checksum;
  64 } __attribute__((packed)) sctp_sctphdr_t;
  65
  66 /* Section 3.2.  Chunk Field Descriptions. */
  67 typedef struct sctp_chunkhdr {
  68         __u8 type;
  69         __u8 flags;
  70         __u16 length;
  71 } __attribute__((packed)) sctp_chunkhdr_t;
  72
  73
  74 /* Section 3.2.  Chunk Type Values.
  75  * [Chunk Type] identifies the type of information contained in the Chunk
  76  * Value field. It takes a value from 0 to 254. The value of 255 is
  77  * reserved for future use as an extension field.
  78  */
  79 typedef enum {
  80         SCTP_CID_DATA                   = 0,
  81         SCTP_CID_INIT                   = 1,
  82         SCTP_CID_INIT_ACK               = 2,
  83         SCTP_CID_SACK                   = 3,
  84         SCTP_CID_HEARTBEAT              = 4,
  85         SCTP_CID_HEARTBEAT_ACK          = 5,
  86         SCTP_CID_ABORT                  = 6,
  87         SCTP_CID_SHUTDOWN               = 7,
  88         SCTP_CID_SHUTDOWN_ACK           = 8,
  89         SCTP_CID_ERROR                  = 9,
  90         SCTP_CID_COOKIE_ECHO            = 10,
  91         SCTP_CID_COOKIE_ACK             = 11,
  92         SCTP_CID_ECN_ECNE               = 12,
  93         SCTP_CID_ECN_CWR                = 13,
  94         SCTP_CID_SHUTDOWN_COMPLETE      = 14,
  95
  96         /* PR-SCTP Sec 3.2 */
  97         SCTP_CID_FWD_TSN                = 0xC0,
  98
  99         /* Use hex, as defined in ADDIP sec. 3.1 */
 100         SCTP_CID_ASCONF                 = 0xC1,
 101         SCTP_CID_ASCONF_ACK             = 0x80,
 102 } sctp_cid_t; /* enum */
 103
 104
 105 /* Section 3.2
 106  *  Chunk Types are encoded such that the highest-order two bits specify
 107  *  the action that must be taken if the processing endpoint does not
 108  *  recognize the Chunk Type.
 109  */
 110 typedef enum {
 111         SCTP_CID_ACTION_DISCARD     = 0x00,
 112         SCTP_CID_ACTION_DISCARD_ERR = 0x40,
 113         SCTP_CID_ACTION_SKIP        = 0x80,
 114         SCTP_CID_ACTION_SKIP_ERR    = 0xc0,
 115 } sctp_cid_action_t;
 116
 117 enum { SCTP_CID_ACTION_MASK = 0xc0, };
 118
 119 /* This flag is used in Chunk Flags for ABORT and SHUTDOWN COMPLETE.
 120  *
 121  * 3.3.7 Abort Association (ABORT) (6):
 122  *    The T bit is set to 0 if the sender had a TCB that it destroyed.
 123  *    If the sender did not have a TCB it should set this bit to 1.
 124  */
 125 enum { SCTP_CHUNK_FLAG_T = 0x01 };
 126
 127 /*
 128  *  Set the T bit
 129  *
 130  *      0                   1                   2                   3
 131  *      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
 132  *     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 133  *     |   Type = 14   |Reserved     |T|      Length = 4               |
 134  *     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 135  *
 136  * Chunk Flags: 8 bits
 137  *
 138  *   Reserved:  7 bits
 139  *     Set to 0 on transmit and ignored on receipt.
 140  *
 141  *   T bit:  1 bit
 142  *     The T bit is set to 0 if the sender had a TCB that it destroyed. If
 143  *     the sender did NOT have a TCB it should set this bit to 1.
 144  *
 145  * Note: Special rules apply to this chunk for verification, please
 146  * see Section 8.5.1 for details.
 147  */
 148
 149 #define sctp_test_T_bit(c)    ((c)->chunk_hdr->flags & SCTP_CHUNK_FLAG_T)
 150
 151 /* RFC 2960
 152  * Section 3.2.1 Optional/Variable-length Parmaeter Format.
 153  */
 154
 155 typedef struct sctp_paramhdr {
 156         __u16 type;
 157         __u16 length;
 158 } __attribute__((packed)) sctp_paramhdr_t;
 159
 160 typedef enum {
 161
 162         /* RFC 2960 Section 3.3.5 */
 163         SCTP_PARAM_HEARTBEAT_INFO               = __constant_htons(1),
 164         /* RFC 2960 Section 3.3.2.1 */
 165         SCTP_PARAM_IPV4_ADDRESS                 = __constant_htons(5),
 166         SCTP_PARAM_IPV6_ADDRESS                 = __constant_htons(6),
 167         SCTP_PARAM_STATE_COOKIE                 = __constant_htons(7),
 168         SCTP_PARAM_UNRECOGNIZED_PARAMETERS      = __constant_htons(8),
 169         SCTP_PARAM_COOKIE_PRESERVATIVE          = __constant_htons(9),
 170         SCTP_PARAM_HOST_NAME_ADDRESS            = __constant_htons(11),
 171         SCTP_PARAM_SUPPORTED_ADDRESS_TYPES      = __constant_htons(12),
 172         SCTP_PARAM_ECN_CAPABLE                  = __constant_htons(0x8000),
 173
 174         /* PR-SCTP Sec 3.1 */
 175         SCTP_PARAM_FWD_TSN_SUPPORT      = __constant_htons(0xc000),
 176
 177         /* Add-IP Extension. Section 3.2 */
 178         SCTP_PARAM_ADD_IP               = __constant_htons(0xc001),
 179         SCTP_PARAM_DEL_IP               = __constant_htons(0xc002),
 180         SCTP_PARAM_ERR_CAUSE            = __constant_htons(0xc003),
 181         SCTP_PARAM_SET_PRIMARY          = __constant_htons(0xc004),
 182         SCTP_PARAM_SUCCESS_REPORT       = __constant_htons(0xc005),
 183         SCTP_PARAM_ADAPTION_LAYER_IND   = __constant_htons(0xc006),
 184
 185 } sctp_param_t; /* enum */
 186
 187
 188 /* RFC 2960 Section 3.2.1
 189  *  The Parameter Types are encoded such that the highest-order two bits
 190  *  specify the action that must be taken if the processing endpoint does
 191  *  not recognize the Parameter Type.
 192  *
 193  */
 194 typedef enum {
 195         SCTP_PARAM_ACTION_DISCARD     = __constant_htons(0x0000),
 196         SCTP_PARAM_ACTION_DISCARD_ERR = __constant_htons(0x4000),
 197         SCTP_PARAM_ACTION_SKIP        = __constant_htons(0x8000),
 198         SCTP_PARAM_ACTION_SKIP_ERR    = __constant_htons(0xc000),
 199 } sctp_param_action_t;
 200
 201 enum { SCTP_PARAM_ACTION_MASK = __constant_htons(0xc000), };
 202
 203 /* RFC 2960 Section 3.3.1 Payload Data (DATA) (0) */
 204
 205 typedef struct sctp_datahdr {
 206         __u32 tsn;
 207         __u16 stream;
 208         __u16 ssn;
 209         __u32 ppid;
 210         __u8  payload[0];
 211 } __attribute__((packed)) sctp_datahdr_t;
 212
 213 typedef struct sctp_data_chunk {
 214         sctp_chunkhdr_t chunk_hdr;
 215         sctp_datahdr_t  data_hdr;
 216 } __attribute__((packed)) sctp_data_chunk_t;
 217
 218 /* DATA Chuck Specific Flags */
 219 enum {
 220         SCTP_DATA_MIDDLE_FRAG   = 0x00,
 221         SCTP_DATA_LAST_FRAG     = 0x01,
 222         SCTP_DATA_FIRST_FRAG    = 0x02,
 223         SCTP_DATA_NOT_FRAG      = 0x03,
 224         SCTP_DATA_UNORDERED     = 0x04,
 225 };
 226 enum { SCTP_DATA_FRAG_MASK = 0x03, };
 227
 228
 229 /* RFC 2960 Section 3.3.2 Initiation (INIT) (1)
 230  *
 231  *  This chunk is used to initiate a SCTP association between two
 232  *  endpoints.
 233  */
 234 typedef struct sctp_inithdr {
 235         __u32 init_tag;
 236         __u32 a_rwnd;
 237         __u16 num_outbound_streams;
 238         __u16 num_inbound_streams;
 239         __u32 initial_tsn;
 240         __u8  params[0];
 241 } __attribute__((packed)) sctp_inithdr_t;
 242
 243 typedef struct sctp_init_chunk {
 244         sctp_chunkhdr_t chunk_hdr;
 245         sctp_inithdr_t init_hdr;
 246 } __attribute__((packed)) sctp_init_chunk_t;
 247
 248
 249 /* Section 3.3.2.1. IPv4 Address Parameter (5) */
 250 typedef struct sctp_ipv4addr_param {
 251         sctp_paramhdr_t param_hdr;
 252         struct in_addr  addr;
 253 } __attribute__((packed)) sctp_ipv4addr_param_t;
 254
 255 /* Section 3.3.2.1. IPv6 Address Parameter (6) */
 256 typedef struct sctp_ipv6addr_param {
 257         sctp_paramhdr_t param_hdr;
 258         struct in6_addr addr;
 259 } __attribute__((packed)) sctp_ipv6addr_param_t;
 260
 261 /* Section 3.3.2.1 Cookie Preservative (9) */
 262 typedef struct sctp_cookie_preserve_param {
 263         sctp_paramhdr_t param_hdr;
 264         uint32_t        lifespan_increment;
 265 } __attribute__((packed)) sctp_cookie_preserve_param_t;
 266
 267 /* Section 3.3.2.1 Host Name Address (11) */
 268 typedef struct sctp_hostname_param {
 269         sctp_paramhdr_t param_hdr;
 270         uint8_t hostname[0];
 271 } __attribute__((packed)) sctp_hostname_param_t;
 272
 273 /* Section 3.3.2.1 Supported Address Types (12) */
 274 typedef struct sctp_supported_addrs_param {
 275         sctp_paramhdr_t param_hdr;
 276         uint16_t types[0];
 277 } __attribute__((packed)) sctp_supported_addrs_param_t;
 278
 279 /* Appendix A. ECN Capable (32768) */
 280 typedef struct sctp_ecn_capable_param {
 281         sctp_paramhdr_t param_hdr;
 282 } __attribute__((packed)) sctp_ecn_capable_param_t;
 283
 284
 285
 286 /* RFC 2960.  Section 3.3.3 Initiation Acknowledgement (INIT ACK) (2):
 287  *   The INIT ACK chunk is used to acknowledge the initiation of an SCTP
 288  *   association.
 289  */
 290 typedef sctp_init_chunk_t sctp_initack_chunk_t;
 291
 292 /* Section 3.3.3.1 State Cookie (7) */
 293 typedef struct sctp_cookie_param {
 294         sctp_paramhdr_t p;
 295         __u8 body[0];
 296 } __attribute__((packed)) sctp_cookie_param_t;
 297
 298 /* Section 3.3.3.1 Unrecognized Parameters (8) */
 299 typedef struct sctp_unrecognized_param {
 300         sctp_paramhdr_t param_hdr;
 301         sctp_paramhdr_t unrecognized;
 302 } __attribute__((packed)) sctp_unrecognized_param_t;
 303
 304
 305
 306 /*
 307  * 3.3.4 Selective Acknowledgement (SACK) (3):
 308  *
 309  *  This chunk is sent to the peer endpoint to acknowledge received DATA
 310  *  chunks and to inform the peer endpoint of gaps in the received
 311  *  subsequences of DATA chunks as represented by their TSNs.
 312  */
 313
 314 typedef struct sctp_gap_ack_block {
 315         __u16 start;
 316         __u16 end;
 317 } __attribute__((packed)) sctp_gap_ack_block_t;
 318
 319 typedef uint32_t sctp_dup_tsn_t;
 320
 321 typedef union {
 322         sctp_gap_ack_block_t    gab;
 323         sctp_dup_tsn_t          dup;
 324 } sctp_sack_variable_t;
 325
 326 typedef struct sctp_sackhdr {
 327         __u32 cum_tsn_ack;
 328         __u32 a_rwnd;
 329         __u16 num_gap_ack_blocks;
 330         __u16 num_dup_tsns;
 331         sctp_sack_variable_t variable[0];
 332 } __attribute__((packed)) sctp_sackhdr_t;
 333
 334 typedef struct sctp_sack_chunk {
 335         sctp_chunkhdr_t chunk_hdr;
 336         sctp_sackhdr_t sack_hdr;
 337 } __attribute__((packed)) sctp_sack_chunk_t;
 338
 339
 340 /* RFC 2960.  Section 3.3.5 Heartbeat Request (HEARTBEAT) (4):
 341  *
 342  *  An endpoint should send this chunk to its peer endpoint to probe the
 343  *  reachability of a particular destination transport address defined in
 344  *  the present association.
 345  */
 346
 347 typedef struct sctp_heartbeathdr {
 348         sctp_paramhdr_t info;
 349 } __attribute__((packed)) sctp_heartbeathdr_t;
 350
 351 typedef struct sctp_heartbeat_chunk {
 352         sctp_chunkhdr_t chunk_hdr;
 353         sctp_heartbeathdr_t hb_hdr;
 354 } __attribute__((packed)) sctp_heartbeat_chunk_t;
 355
 356
 357 /* For the abort and shutdown ACK we must carry the init tag in the
 358  * common header. Just the common header is all that is needed with a
 359  * chunk descriptor.
 360  */
 361 typedef struct sctp_abort_chunk {
 362         sctp_chunkhdr_t uh;
 363 } __attribute__((packed)) sctp_abort_chunkt_t;
 364
 365
 366 /* For the graceful shutdown we must carry the tag (in common header)
 367  * and the highest consecutive acking value.
 368  */
 369 typedef struct sctp_shutdownhdr {
 370         __u32 cum_tsn_ack;
 371 } __attribute__((packed)) sctp_shutdownhdr_t;
 372
 373 struct sctp_shutdown_chunk_t {
 374         sctp_chunkhdr_t    chunk_hdr;
 375         sctp_shutdownhdr_t shutdown_hdr;
 376 } __attribute__ ((packed));
 377
 378 /* RFC 2960.  Section 3.3.10 Operation Error (ERROR) (9) */
 379
 380 typedef struct sctp_errhdr {
 381         __u16 cause;
 382         __u16 length;
 383         __u8  variable[0];
 384 } __attribute__((packed)) sctp_errhdr_t;
 385
 386 typedef struct sctp_operr_chunk {
 387         sctp_chunkhdr_t chunk_hdr;
 388         sctp_errhdr_t   err_hdr;
 389 } __attribute__((packed)) sctp_operr_chunk_t;
 390
 391 /* RFC 2960 3.3.10 - Operation Error
 392  *
 393  * Cause Code: 16 bits (unsigned integer)
 394  *
 395  *     Defines the type of error conditions being reported.
 396  *    Cause Code
 397  *     Value           Cause Code
 398  *     ---------      ----------------
 399  *      1              Invalid Stream Identifier
 400  *      2              Missing Mandatory Parameter
 401  *      3              Stale Cookie Error
 402  *      4              Out of Resource
 403  *      5              Unresolvable Address
 404  *      6              Unrecognized Chunk Type
 405  *      7              Invalid Mandatory Parameter
 406  *      8              Unrecognized Parameters
 407  *      9              No User Data
 408  *     10              Cookie Received While Shutting Down
 409  */
 410 typedef enum {
 411
 412         SCTP_ERROR_NO_ERROR        = __constant_htons(0x00),
 413         SCTP_ERROR_INV_STRM        = __constant_htons(0x01),
 414         SCTP_ERROR_MISS_PARAM      = __constant_htons(0x02),
 415         SCTP_ERROR_STALE_COOKIE    = __constant_htons(0x03),
 416         SCTP_ERROR_NO_RESOURCE     = __constant_htons(0x04),
 417         SCTP_ERROR_DNS_FAILED      = __constant_htons(0x05),
 418         SCTP_ERROR_UNKNOWN_CHUNK   = __constant_htons(0x06),
 419         SCTP_ERROR_INV_PARAM       = __constant_htons(0x07),
 420         SCTP_ERROR_UNKNOWN_PARAM   = __constant_htons(0x08),
 421         SCTP_ERROR_NO_DATA         = __constant_htons(0x09),
 422         SCTP_ERROR_COOKIE_IN_SHUTDOWN = __constant_htons(0x0a),
 423
 424
 425         /* SCTP Implementation Guide:
 426          *  11  Restart of an association with new addresses
 427          *  12  User Initiated Abort
 428          *  13  Protocol Violation
 429          */
 430
 431         SCTP_ERROR_RESTART         = __constant_htons(0x0b),
 432         SCTP_ERROR_USER_ABORT      = __constant_htons(0x0c),
 433         SCTP_ERROR_PROTO_VIOLATION = __constant_htons(0x0d),
 434
 435         /* ADDIP Section 3.3  New Error Causes
 436          *
 437          * Four new Error Causes are added to the SCTP Operational Errors,
 438          * primarily for use in the ASCONF-ACK chunk.
 439          *
 440          * Value          Cause Code
 441          * ---------      ----------------
 442          * 0x0100          Request to Delete Last Remaining IP Address.
 443          * 0x0101          Operation Refused Due to Resource Shortage.
 444          * 0x0102          Request to Delete Source IP Address.
 445          * 0x0103          Association Aborted due to illegal ASCONF-ACK
 446          * 0x0104          Request refused - no authorization.
 447          */
 448         SCTP_ERROR_DEL_LAST_IP  = __constant_htons(0x0100),
 449         SCTP_ERROR_RSRC_LOW     = __constant_htons(0x0101),
 450         SCTP_ERROR_DEL_SRC_IP   = __constant_htons(0x0102),
 451         SCTP_ERROR_ASCONF_ACK   = __constant_htons(0x0103),
 452         SCTP_ERROR_REQ_REFUSED  = __constant_htons(0x0104)
 453 } sctp_error_t;
 454
 455
 456
 457 /* RFC 2960.  Appendix A.  Explicit Congestion Notification.
 458  *   Explicit Congestion Notification Echo (ECNE) (12)
 459  */
 460 typedef struct sctp_ecnehdr {
 461         __u32 lowest_tsn;
 462 } sctp_ecnehdr_t;
 463
 464 typedef struct sctp_ecne_chunk {
 465         sctp_chunkhdr_t chunk_hdr;
 466         sctp_ecnehdr_t ence_hdr;
 467 } __attribute__((packed)) sctp_ecne_chunk_t;
 468
 469 /* RFC 2960.  Appendix A.  Explicit Congestion Notification.
 470  *   Congestion Window Reduced (CWR) (13)
 471  */
 472 typedef struct sctp_cwrhdr {
 473         __u32 lowest_tsn;
 474 } sctp_cwrhdr_t;
 475
 476 typedef struct sctp_cwr_chunk {
 477         sctp_chunkhdr_t chunk_hdr;
 478         sctp_cwrhdr_t cwr_hdr;
 479 } __attribute__((packed)) sctp_cwr_chunk_t;
 480
 481 /* PR-SCTP
 482  * 3.2 Forward Cumulative TSN Chunk Definition (FORWARD TSN)
 483  *
 484  * Forward Cumulative TSN chunk has the following format:
 485  *
 486  *        0                   1                   2                   3
 487  *        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
 488  *      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 489  *      |   Type = 192  |  Flags = 0x00 |        Length = Variable      |
 490  *      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 491  *      |                      New Cumulative TSN                       |
 492  *      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 493  *      |         Stream-1              |       Stream Sequence-1       |
 494  *      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 495  *      \                                                               /
 496  *      /                                                               \
 497  *      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 498  *      |         Stream-N              |       Stream Sequence-N       |
 499  *      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 500  *
 501  *      Chunk Flags:
 502  *
 503  *        Set to all zeros on transmit and ignored on receipt.
 504  *
 505  *      New Cumulative TSN: 32 bit u_int
 506  *
 507  *       This indicates the new cumulative TSN to the data receiver. Upon
 508  *       the reception of this value, the data receiver MUST consider
 509  *       any missing TSNs earlier than or equal to this value as received
 510  *       and stop reporting them as gaps in any subsequent SACKs.
 511  *
 512  *      Stream-N: 16 bit u_int
 513  *
 514  *       This field holds a stream number that was skipped by this
 515  *       FWD-TSN.
 516  *
 517  *      Stream Sequence-N: 16 bit u_int
 518  *       This field holds the sequence number associated with the stream
 519  *       that was skipped. The stream sequence field holds the largest stream
 520  *       sequence number in this stream being skipped.  The receiver of
 521  *       the FWD-TSN's can use the Stream-N and Stream Sequence-N fields
 522  *       to enable delivery of any stranded TSN's that remain on the stream
 523  *       re-ordering queues. This field MUST NOT report TSN's corresponding
 524  *       to DATA chunk that are marked as unordered. For ordered DATA
 525  *       chunks this field MUST be filled in.
 526  */
 527 struct sctp_fwdtsn_skip {
 528         __u16 stream;
 529         __u16 ssn;
 530 } __attribute__((packed));
 531
 532 struct sctp_fwdtsn_hdr {
 533         __u32 new_cum_tsn;
 534         struct sctp_fwdtsn_skip skip[0];
 535 } __attribute((packed));
 536
 537 struct sctp_fwdtsn_chunk {
 538         struct sctp_chunkhdr chunk_hdr;
 539         struct sctp_fwdtsn_hdr fwdtsn_hdr;
 540 } __attribute((packed));
 541
 542
 543 /* ADDIP
 544  * Section 3.1.1 Address Configuration Change Chunk (ASCONF)
 545  *
 546  *      Serial Number: 32 bits (unsigned integer)
 547  *      This value represents a Serial Number for the ASCONF Chunk. The
 548  *      valid range of Serial Number is from 0 to 2^32-1.
 549  *      Serial Numbers wrap back to 0 after reaching 2^32 -1.
 550  *
 551  *      Address Parameter: 8 or 20 bytes (depending on type)
 552  *      The address is an address of the sender of the ASCONF chunk,
 553  *      the address MUST be considered part of the association by the
 554  *      peer endpoint. This field may be used by the receiver of the
 555  *      ASCONF to help in finding the association. This parameter MUST
 556  *      be present in every ASCONF message i.e. it is a mandatory TLV
 557  *      parameter.
 558  *
 559  *      ASCONF Parameter: TLV format
 560  *      Each Address configuration change is represented by a TLV
 561  *      parameter as defined in Section 3.2. One or more requests may
 562  *      be present in an ASCONF Chunk.
 563  *
 564  * Section 3.1.2 Address Configuration Acknowledgement Chunk (ASCONF-ACK)
 565  *
 566  *      Serial Number: 32 bits (unsigned integer)
 567  *      This value represents the Serial Number for the received ASCONF
 568  *      Chunk that is acknowledged by this chunk. This value is copied
 569  *      from the received ASCONF Chunk.
 570  *
 571  *      ASCONF Parameter Response: TLV format
 572  *      The ASCONF Parameter Response is used in the ASCONF-ACK to
 573  *      report status of ASCONF processing.
 574  */
 575 typedef struct sctp_addip_param {
 576         sctp_paramhdr_t param_hdr;
 577         __u32           crr_id;
 578 } __attribute__((packed)) sctp_addip_param_t;
 579
 580 typedef struct sctp_addiphdr {
 581         __u32   serial;
 582         __u8    params[0];
 583 } __attribute__((packed)) sctp_addiphdr_t;
 584
 585 typedef struct sctp_addip_chunk {
 586         sctp_chunkhdr_t chunk_hdr;
 587         sctp_addiphdr_t addip_hdr;
 588 } __attribute__((packed)) sctp_addip_chunk_t;
 589
 590 #endif /* __LINUX_SCTP_H__ */