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         __be16 source;
  61         __be16 dest;
  62         __be32 vtag;
  63         __be32 checksum;
  64 } __attribute__((packed)) sctp_sctphdr_t;
  65
  66 #ifdef __KERNEL__
  67 #include <linux/skbuff.h>
  68
  69 static inline struct sctphdr *sctp_hdr(const struct sk_buff *skb)
  70 {
  71         return (struct sctphdr *)skb_transport_header(skb);
  72 }
  73 #endif
  74
  75 /* Section 3.2.  Chunk Field Descriptions. */
  76 typedef struct sctp_chunkhdr {
  77         __u8 type;
  78         __u8 flags;
  79         __be16 length;
  80 } __attribute__((packed)) sctp_chunkhdr_t;
  81
  82
  83 /* Section 3.2.  Chunk Type Values.
  84  * [Chunk Type] identifies the type of information contained in the Chunk
  85  * Value field. It takes a value from 0 to 254. The value of 255 is
  86  * reserved for future use as an extension field.
  87  */
  88 typedef enum {
  89         SCTP_CID_DATA                   = 0,
  90         SCTP_CID_INIT                   = 1,
  91         SCTP_CID_INIT_ACK               = 2,
  92         SCTP_CID_SACK                   = 3,
  93         SCTP_CID_HEARTBEAT              = 4,
  94         SCTP_CID_HEARTBEAT_ACK          = 5,
  95         SCTP_CID_ABORT                  = 6,
  96         SCTP_CID_SHUTDOWN               = 7,
  97         SCTP_CID_SHUTDOWN_ACK           = 8,
  98         SCTP_CID_ERROR                  = 9,
  99         SCTP_CID_COOKIE_ECHO            = 10,
 100         SCTP_CID_COOKIE_ACK             = 11,
 101         SCTP_CID_ECN_ECNE               = 12,
 102         SCTP_CID_ECN_CWR                = 13,
 103         SCTP_CID_SHUTDOWN_COMPLETE      = 14,
 104
 105         /* PR-SCTP Sec 3.2 */
 106         SCTP_CID_FWD_TSN                = 0xC0,
 107
 108         /* Use hex, as defined in ADDIP sec. 3.1 */
 109         SCTP_CID_ASCONF                 = 0xC1,
 110         SCTP_CID_ASCONF_ACK             = 0x80,
 111 } sctp_cid_t; /* enum */
 112
 113
 114 /* Section 3.2
 115  *  Chunk Types are encoded such that the highest-order two bits specify
 116  *  the action that must be taken if the processing endpoint does not
 117  *  recognize the Chunk Type.
 118  */
 119 typedef enum {
 120         SCTP_CID_ACTION_DISCARD     = 0x00,
 121         SCTP_CID_ACTION_DISCARD_ERR = 0x40,
 122         SCTP_CID_ACTION_SKIP        = 0x80,
 123         SCTP_CID_ACTION_SKIP_ERR    = 0xc0,
 124 } sctp_cid_action_t;
 125
 126 enum { SCTP_CID_ACTION_MASK = 0xc0, };
 127
 128 /* This flag is used in Chunk Flags for ABORT and SHUTDOWN COMPLETE.
 129  *
 130  * 3.3.7 Abort Association (ABORT) (6):
 131  *    The T bit is set to 0 if the sender had a TCB that it destroyed.
 132  *    If the sender did not have a TCB it should set this bit to 1.
 133  */
 134 enum { SCTP_CHUNK_FLAG_T = 0x01 };
 135
 136 /*
 137  *  Set the T bit
 138  *
 139  *      0                   1                   2                   3
 140  *      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
 141  *     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 142  *     |   Type = 14   |Reserved     |T|      Length = 4               |
 143  *     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 144  *
 145  * Chunk Flags: 8 bits
 146  *
 147  *   Reserved:  7 bits
 148  *     Set to 0 on transmit and ignored on receipt.
 149  *
 150  *   T bit:  1 bit
 151  *     The T bit is set to 0 if the sender had a TCB that it destroyed. If
 152  *     the sender did NOT have a TCB it should set this bit to 1.
 153  *
 154  * Note: Special rules apply to this chunk for verification, please
 155  * see Section 8.5.1 for details.
 156  */
 157
 158 #define sctp_test_T_bit(c)    ((c)->chunk_hdr->flags & SCTP_CHUNK_FLAG_T)
 159
 160 /* RFC 2960
 161  * Section 3.2.1 Optional/Variable-length Parmaeter Format.
 162  */
 163
 164 typedef struct sctp_paramhdr {
 165         __be16 type;
 166         __be16 length;
 167 } __attribute__((packed)) sctp_paramhdr_t;
 168
 169 typedef enum {
 170
 171         /* RFC 2960 Section 3.3.5 */
 172         SCTP_PARAM_HEARTBEAT_INFO               = __constant_htons(1),
 173         /* RFC 2960 Section 3.3.2.1 */
 174         SCTP_PARAM_IPV4_ADDRESS                 = __constant_htons(5),
 175         SCTP_PARAM_IPV6_ADDRESS                 = __constant_htons(6),
 176         SCTP_PARAM_STATE_COOKIE                 = __constant_htons(7),
 177         SCTP_PARAM_UNRECOGNIZED_PARAMETERS      = __constant_htons(8),
 178         SCTP_PARAM_COOKIE_PRESERVATIVE          = __constant_htons(9),
 179         SCTP_PARAM_HOST_NAME_ADDRESS            = __constant_htons(11),
 180         SCTP_PARAM_SUPPORTED_ADDRESS_TYPES      = __constant_htons(12),
 181         SCTP_PARAM_ECN_CAPABLE                  = __constant_htons(0x8000),
 182
 183         /* PR-SCTP Sec 3.1 */
 184         SCTP_PARAM_FWD_TSN_SUPPORT      = __constant_htons(0xc000),
 185
 186         /* Add-IP Extension. Section 3.2 */
 187         SCTP_PARAM_ADD_IP               = __constant_htons(0xc001),
 188         SCTP_PARAM_DEL_IP               = __constant_htons(0xc002),
 189         SCTP_PARAM_ERR_CAUSE            = __constant_htons(0xc003),
 190         SCTP_PARAM_SET_PRIMARY          = __constant_htons(0xc004),
 191         SCTP_PARAM_SUCCESS_REPORT       = __constant_htons(0xc005),
 192         SCTP_PARAM_ADAPTATION_LAYER_IND = __constant_htons(0xc006),
 193
 194 } sctp_param_t; /* enum */
 195
 196
 197 /* RFC 2960 Section 3.2.1
 198  *  The Parameter Types are encoded such that the highest-order two bits
 199  *  specify the action that must be taken if the processing endpoint does
 200  *  not recognize the Parameter Type.
 201  *
 202  */
 203 typedef enum {
 204         SCTP_PARAM_ACTION_DISCARD     = __constant_htons(0x0000),
 205         SCTP_PARAM_ACTION_DISCARD_ERR = __constant_htons(0x4000),
 206         SCTP_PARAM_ACTION_SKIP        = __constant_htons(0x8000),
 207         SCTP_PARAM_ACTION_SKIP_ERR    = __constant_htons(0xc000),
 208 } sctp_param_action_t;
 209
 210 enum { SCTP_PARAM_ACTION_MASK = __constant_htons(0xc000), };
 211
 212 /* RFC 2960 Section 3.3.1 Payload Data (DATA) (0) */
 213
 214 typedef struct sctp_datahdr {
 215         __be32 tsn;
 216         __be16 stream;
 217         __be16 ssn;
 218         __be32 ppid;
 219         __u8  payload[0];
 220 } __attribute__((packed)) sctp_datahdr_t;
 221
 222 typedef struct sctp_data_chunk {
 223         sctp_chunkhdr_t chunk_hdr;
 224         sctp_datahdr_t  data_hdr;
 225 } __attribute__((packed)) sctp_data_chunk_t;
 226
 227 /* DATA Chuck Specific Flags */
 228 enum {
 229         SCTP_DATA_MIDDLE_FRAG   = 0x00,
 230         SCTP_DATA_LAST_FRAG     = 0x01,
 231         SCTP_DATA_FIRST_FRAG    = 0x02,
 232         SCTP_DATA_NOT_FRAG      = 0x03,
 233         SCTP_DATA_UNORDERED     = 0x04,
 234 };
 235 enum { SCTP_DATA_FRAG_MASK = 0x03, };
 236
 237
 238 /* RFC 2960 Section 3.3.2 Initiation (INIT) (1)
 239  *
 240  *  This chunk is used to initiate a SCTP association between two
 241  *  endpoints.
 242  */
 243 typedef struct sctp_inithdr {
 244         __be32 init_tag;
 245         __be32 a_rwnd;
 246         __be16 num_outbound_streams;
 247         __be16 num_inbound_streams;
 248         __be32 initial_tsn;
 249         __u8  params[0];
 250 } __attribute__((packed)) sctp_inithdr_t;
 251
 252 typedef struct sctp_init_chunk {
 253         sctp_chunkhdr_t chunk_hdr;
 254         sctp_inithdr_t init_hdr;
 255 } __attribute__((packed)) sctp_init_chunk_t;
 256
 257
 258 /* Section 3.3.2.1. IPv4 Address Parameter (5) */
 259 typedef struct sctp_ipv4addr_param {
 260         sctp_paramhdr_t param_hdr;
 261         struct in_addr  addr;
 262 } __attribute__((packed)) sctp_ipv4addr_param_t;
 263
 264 /* Section 3.3.2.1. IPv6 Address Parameter (6) */
 265 typedef struct sctp_ipv6addr_param {
 266         sctp_paramhdr_t param_hdr;
 267         struct in6_addr addr;
 268 } __attribute__((packed)) sctp_ipv6addr_param_t;
 269
 270 /* Section 3.3.2.1 Cookie Preservative (9) */
 271 typedef struct sctp_cookie_preserve_param {
 272         sctp_paramhdr_t param_hdr;
 273         __be32          lifespan_increment;
 274 } __attribute__((packed)) sctp_cookie_preserve_param_t;
 275
 276 /* Section 3.3.2.1 Host Name Address (11) */
 277 typedef struct sctp_hostname_param {
 278         sctp_paramhdr_t param_hdr;
 279         uint8_t hostname[0];
 280 } __attribute__((packed)) sctp_hostname_param_t;
 281
 282 /* Section 3.3.2.1 Supported Address Types (12) */
 283 typedef struct sctp_supported_addrs_param {
 284         sctp_paramhdr_t param_hdr;
 285         __be16 types[0];
 286 } __attribute__((packed)) sctp_supported_addrs_param_t;
 287
 288 /* Appendix A. ECN Capable (32768) */
 289 typedef struct sctp_ecn_capable_param {
 290         sctp_paramhdr_t param_hdr;
 291 } __attribute__((packed)) sctp_ecn_capable_param_t;
 292
 293 /* ADDIP Section 3.2.6 Adaptation Layer Indication */
 294 typedef struct sctp_adaptation_ind_param {
 295         struct sctp_paramhdr param_hdr;
 296         __be32 adaptation_ind;
 297 } __attribute__((packed)) sctp_adaptation_ind_param_t;
 298
 299 /* RFC 2960.  Section 3.3.3 Initiation Acknowledgement (INIT ACK) (2):
 300  *   The INIT ACK chunk is used to acknowledge the initiation of an SCTP
 301  *   association.
 302  */
 303 typedef sctp_init_chunk_t sctp_initack_chunk_t;
 304
 305 /* Section 3.3.3.1 State Cookie (7) */
 306 typedef struct sctp_cookie_param {
 307         sctp_paramhdr_t p;
 308         __u8 body[0];
 309 } __attribute__((packed)) sctp_cookie_param_t;
 310
 311 /* Section 3.3.3.1 Unrecognized Parameters (8) */
 312 typedef struct sctp_unrecognized_param {
 313         sctp_paramhdr_t param_hdr;
 314         sctp_paramhdr_t unrecognized;
 315 } __attribute__((packed)) sctp_unrecognized_param_t;
 316
 317
 318
 319 /*
 320  * 3.3.4 Selective Acknowledgement (SACK) (3):
 321  *
 322  *  This chunk is sent to the peer endpoint to acknowledge received DATA
 323  *  chunks and to inform the peer endpoint of gaps in the received
 324  *  subsequences of DATA chunks as represented by their TSNs.
 325  */
 326
 327 typedef struct sctp_gap_ack_block {
 328         __be16 start;
 329         __be16 end;
 330 } __attribute__((packed)) sctp_gap_ack_block_t;
 331
 332 typedef __be32 sctp_dup_tsn_t;
 333
 334 typedef union {
 335         sctp_gap_ack_block_t    gab;
 336         sctp_dup_tsn_t          dup;
 337 } sctp_sack_variable_t;
 338
 339 typedef struct sctp_sackhdr {
 340         __be32 cum_tsn_ack;
 341         __be32 a_rwnd;
 342         __be16 num_gap_ack_blocks;
 343         __be16 num_dup_tsns;
 344         sctp_sack_variable_t variable[0];
 345 } __attribute__((packed)) sctp_sackhdr_t;
 346
 347 typedef struct sctp_sack_chunk {
 348         sctp_chunkhdr_t chunk_hdr;
 349         sctp_sackhdr_t sack_hdr;
 350 } __attribute__((packed)) sctp_sack_chunk_t;
 351
 352
 353 /* RFC 2960.  Section 3.3.5 Heartbeat Request (HEARTBEAT) (4):
 354  *
 355  *  An endpoint should send this chunk to its peer endpoint to probe the
 356  *  reachability of a particular destination transport address defined in
 357  *  the present association.
 358  */
 359
 360 typedef struct sctp_heartbeathdr {
 361         sctp_paramhdr_t info;
 362 } __attribute__((packed)) sctp_heartbeathdr_t;
 363
 364 typedef struct sctp_heartbeat_chunk {
 365         sctp_chunkhdr_t chunk_hdr;
 366         sctp_heartbeathdr_t hb_hdr;
 367 } __attribute__((packed)) sctp_heartbeat_chunk_t;
 368
 369
 370 /* For the abort and shutdown ACK we must carry the init tag in the
 371  * common header. Just the common header is all that is needed with a
 372  * chunk descriptor.
 373  */
 374 typedef struct sctp_abort_chunk {
 375         sctp_chunkhdr_t uh;
 376 } __attribute__((packed)) sctp_abort_chunk_t;
 377
 378
 379 /* For the graceful shutdown we must carry the tag (in common header)
 380  * and the highest consecutive acking value.
 381  */
 382 typedef struct sctp_shutdownhdr {
 383         __be32 cum_tsn_ack;
 384 } __attribute__((packed)) sctp_shutdownhdr_t;
 385
 386 struct sctp_shutdown_chunk_t {
 387         sctp_chunkhdr_t    chunk_hdr;
 388         sctp_shutdownhdr_t shutdown_hdr;
 389 } __attribute__ ((packed));
 390
 391 /* RFC 2960.  Section 3.3.10 Operation Error (ERROR) (9) */
 392
 393 typedef struct sctp_errhdr {
 394         __be16 cause;
 395         __be16 length;
 396         __u8  variable[0];
 397 } __attribute__((packed)) sctp_errhdr_t;
 398
 399 typedef struct sctp_operr_chunk {
 400         sctp_chunkhdr_t chunk_hdr;
 401         sctp_errhdr_t   err_hdr;
 402 } __attribute__((packed)) sctp_operr_chunk_t;
 403
 404 /* RFC 2960 3.3.10 - Operation Error
 405  *
 406  * Cause Code: 16 bits (unsigned integer)
 407  *
 408  *     Defines the type of error conditions being reported.
 409  *    Cause Code
 410  *     Value           Cause Code
 411  *     ---------      ----------------
 412  *      1              Invalid Stream Identifier
 413  *      2              Missing Mandatory Parameter
 414  *      3              Stale Cookie Error
 415  *      4              Out of Resource
 416  *      5              Unresolvable Address
 417  *      6              Unrecognized Chunk Type
 418  *      7              Invalid Mandatory Parameter
 419  *      8              Unrecognized Parameters
 420  *      9              No User Data
 421  *     10              Cookie Received While Shutting Down
 422  */
 423 typedef enum {
 424
 425         SCTP_ERROR_NO_ERROR        = __constant_htons(0x00),
 426         SCTP_ERROR_INV_STRM        = __constant_htons(0x01),
 427         SCTP_ERROR_MISS_PARAM      = __constant_htons(0x02),
 428         SCTP_ERROR_STALE_COOKIE    = __constant_htons(0x03),
 429         SCTP_ERROR_NO_RESOURCE     = __constant_htons(0x04),
 430         SCTP_ERROR_DNS_FAILED      = __constant_htons(0x05),
 431         SCTP_ERROR_UNKNOWN_CHUNK   = __constant_htons(0x06),
 432         SCTP_ERROR_INV_PARAM       = __constant_htons(0x07),
 433         SCTP_ERROR_UNKNOWN_PARAM   = __constant_htons(0x08),
 434         SCTP_ERROR_NO_DATA         = __constant_htons(0x09),
 435         SCTP_ERROR_COOKIE_IN_SHUTDOWN = __constant_htons(0x0a),
 436
 437
 438         /* SCTP Implementation Guide:
 439          *  11  Restart of an association with new addresses
 440          *  12  User Initiated Abort
 441          *  13  Protocol Violation
 442          */
 443
 444         SCTP_ERROR_RESTART         = __constant_htons(0x0b),
 445         SCTP_ERROR_USER_ABORT      = __constant_htons(0x0c),
 446         SCTP_ERROR_PROTO_VIOLATION = __constant_htons(0x0d),
 447
 448         /* ADDIP Section 3.3  New Error Causes
 449          *
 450          * Four new Error Causes are added to the SCTP Operational Errors,
 451          * primarily for use in the ASCONF-ACK chunk.
 452          *
 453          * Value          Cause Code
 454          * ---------      ----------------
 455          * 0x0100          Request to Delete Last Remaining IP Address.
 456          * 0x0101          Operation Refused Due to Resource Shortage.
 457          * 0x0102          Request to Delete Source IP Address.
 458          * 0x0103          Association Aborted due to illegal ASCONF-ACK
 459          * 0x0104          Request refused - no authorization.
 460          */
 461         SCTP_ERROR_DEL_LAST_IP  = __constant_htons(0x0100),
 462         SCTP_ERROR_RSRC_LOW     = __constant_htons(0x0101),
 463         SCTP_ERROR_DEL_SRC_IP   = __constant_htons(0x0102),
 464         SCTP_ERROR_ASCONF_ACK   = __constant_htons(0x0103),
 465         SCTP_ERROR_REQ_REFUSED  = __constant_htons(0x0104)
 466 } sctp_error_t;
 467
 468
 469
 470 /* RFC 2960.  Appendix A.  Explicit Congestion Notification.
 471  *   Explicit Congestion Notification Echo (ECNE) (12)
 472  */
 473 typedef struct sctp_ecnehdr {
 474         __be32 lowest_tsn;
 475 } sctp_ecnehdr_t;
 476
 477 typedef struct sctp_ecne_chunk {
 478         sctp_chunkhdr_t chunk_hdr;
 479         sctp_ecnehdr_t ence_hdr;
 480 } __attribute__((packed)) sctp_ecne_chunk_t;
 481
 482 /* RFC 2960.  Appendix A.  Explicit Congestion Notification.
 483  *   Congestion Window Reduced (CWR) (13)
 484  */
 485 typedef struct sctp_cwrhdr {
 486         __be32 lowest_tsn;
 487 } sctp_cwrhdr_t;
 488
 489 typedef struct sctp_cwr_chunk {
 490         sctp_chunkhdr_t chunk_hdr;
 491         sctp_cwrhdr_t cwr_hdr;
 492 } __attribute__((packed)) sctp_cwr_chunk_t;
 493
 494 /* PR-SCTP
 495  * 3.2 Forward Cumulative TSN Chunk Definition (FORWARD TSN)
 496  *
 497  * Forward Cumulative TSN chunk has the following format:
 498  *
 499  *        0                   1                   2                   3
 500  *        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
 501  *      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 502  *      |   Type = 192  |  Flags = 0x00 |        Length = Variable      |
 503  *      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 504  *      |                      New Cumulative TSN                       |
 505  *      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 506  *      |         Stream-1              |       Stream Sequence-1       |
 507  *      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 508  *      \                                                               /
 509  *      /                                                               \
 510  *      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 511  *      |         Stream-N              |       Stream Sequence-N       |
 512  *      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 513  *
 514  *      Chunk Flags:
 515  *
 516  *        Set to all zeros on transmit and ignored on receipt.
 517  *
 518  *      New Cumulative TSN: 32 bit u_int
 519  *
 520  *       This indicates the new cumulative TSN to the data receiver. Upon
 521  *       the reception of this value, the data receiver MUST consider
 522  *       any missing TSNs earlier than or equal to this value as received
 523  *       and stop reporting them as gaps in any subsequent SACKs.
 524  *
 525  *      Stream-N: 16 bit u_int
 526  *
 527  *       This field holds a stream number that was skipped by this
 528  *       FWD-TSN.
 529  *
 530  *      Stream Sequence-N: 16 bit u_int
 531  *       This field holds the sequence number associated with the stream
 532  *       that was skipped. The stream sequence field holds the largest stream
 533  *       sequence number in this stream being skipped.  The receiver of
 534  *       the FWD-TSN's can use the Stream-N and Stream Sequence-N fields
 535  *       to enable delivery of any stranded TSN's that remain on the stream
 536  *       re-ordering queues. This field MUST NOT report TSN's corresponding
 537  *       to DATA chunk that are marked as unordered. For ordered DATA
 538  *       chunks this field MUST be filled in.
 539  */
 540 struct sctp_fwdtsn_skip {
 541         __be16 stream;
 542         __be16 ssn;
 543 } __attribute__((packed));
 544
 545 struct sctp_fwdtsn_hdr {
 546         __be32 new_cum_tsn;
 547         struct sctp_fwdtsn_skip skip[0];
 548 } __attribute((packed));
 549
 550 struct sctp_fwdtsn_chunk {
 551         struct sctp_chunkhdr chunk_hdr;
 552         struct sctp_fwdtsn_hdr fwdtsn_hdr;
 553 } __attribute((packed));
 554
 555
 556 /* ADDIP
 557  * Section 3.1.1 Address Configuration Change Chunk (ASCONF)
 558  *
 559  *      Serial Number: 32 bits (unsigned integer)
 560  *      This value represents a Serial Number for the ASCONF Chunk. The
 561  *      valid range of Serial Number is from 0 to 2^32-1.
 562  *      Serial Numbers wrap back to 0 after reaching 2^32 -1.
 563  *
 564  *      Address Parameter: 8 or 20 bytes (depending on type)
 565  *      The address is an address of the sender of the ASCONF chunk,
 566  *      the address MUST be considered part of the association by the
 567  *      peer endpoint. This field may be used by the receiver of the
 568  *      ASCONF to help in finding the association. This parameter MUST
 569  *      be present in every ASCONF message i.e. it is a mandatory TLV
 570  *      parameter.
 571  *
 572  *      ASCONF Parameter: TLV format
 573  *      Each Address configuration change is represented by a TLV
 574  *      parameter as defined in Section 3.2. One or more requests may
 575  *      be present in an ASCONF Chunk.
 576  *
 577  * Section 3.1.2 Address Configuration Acknowledgement Chunk (ASCONF-ACK)
 578  *
 579  *      Serial Number: 32 bits (unsigned integer)
 580  *      This value represents the Serial Number for the received ASCONF
 581  *      Chunk that is acknowledged by this chunk. This value is copied
 582  *      from the received ASCONF Chunk.
 583  *
 584  *      ASCONF Parameter Response: TLV format
 585  *      The ASCONF Parameter Response is used in the ASCONF-ACK to
 586  *      report status of ASCONF processing.
 587  */
 588 typedef struct sctp_addip_param {
 589         sctp_paramhdr_t param_hdr;
 590         __be32          crr_id;
 591 } __attribute__((packed)) sctp_addip_param_t;
 592
 593 typedef struct sctp_addiphdr {
 594         __be32  serial;
 595         __u8    params[0];
 596 } __attribute__((packed)) sctp_addiphdr_t;
 597
 598 typedef struct sctp_addip_chunk {
 599         sctp_chunkhdr_t chunk_hdr;
 600         sctp_addiphdr_t addip_hdr;
 601 } __attribute__((packed)) sctp_addip_chunk_t;
 602
 603 #endif /* __LINUX_SCTP_H__ */