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         /* AUTH Extension Section 4.1 */
 106         SCTP_CID_AUTH                   = 0x0F,
 107
 108         /* PR-SCTP Sec 3.2 */
 109         SCTP_CID_FWD_TSN                = 0xC0,
 110
 111         /* Use hex, as defined in ADDIP sec. 3.1 */
 112         SCTP_CID_ASCONF                 = 0xC1,
 113         SCTP_CID_ASCONF_ACK             = 0x80,
 114 } sctp_cid_t; /* enum */
 115
 116
 117 /* Section 3.2
 118  *  Chunk Types are encoded such that the highest-order two bits specify
 119  *  the action that must be taken if the processing endpoint does not
 120  *  recognize the Chunk Type.
 121  */
 122 typedef enum {
 123         SCTP_CID_ACTION_DISCARD     = 0x00,
 124         SCTP_CID_ACTION_DISCARD_ERR = 0x40,
 125         SCTP_CID_ACTION_SKIP        = 0x80,
 126         SCTP_CID_ACTION_SKIP_ERR    = 0xc0,
 127 } sctp_cid_action_t;
 128
 129 enum { SCTP_CID_ACTION_MASK = 0xc0, };
 130
 131 /* This flag is used in Chunk Flags for ABORT and SHUTDOWN COMPLETE.
 132  *
 133  * 3.3.7 Abort Association (ABORT) (6):
 134  *    The T bit is set to 0 if the sender had a TCB that it destroyed.
 135  *    If the sender did not have a TCB it should set this bit to 1.
 136  */
 137 enum { SCTP_CHUNK_FLAG_T = 0x01 };
 138
 139 /*
 140  *  Set the T bit
 141  *
 142  *      0                   1                   2                   3
 143  *      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
 144  *     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 145  *     |   Type = 14   |Reserved     |T|      Length = 4               |
 146  *     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 147  *
 148  * Chunk Flags: 8 bits
 149  *
 150  *   Reserved:  7 bits
 151  *     Set to 0 on transmit and ignored on receipt.
 152  *
 153  *   T bit:  1 bit
 154  *     The T bit is set to 0 if the sender had a TCB that it destroyed. If
 155  *     the sender did NOT have a TCB it should set this bit to 1.
 156  *
 157  * Note: Special rules apply to this chunk for verification, please
 158  * see Section 8.5.1 for details.
 159  */
 160
 161 #define sctp_test_T_bit(c)    ((c)->chunk_hdr->flags & SCTP_CHUNK_FLAG_T)
 162
 163 /* RFC 2960
 164  * Section 3.2.1 Optional/Variable-length Parmaeter Format.
 165  */
 166
 167 typedef struct sctp_paramhdr {
 168         __be16 type;
 169         __be16 length;
 170 } __attribute__((packed)) sctp_paramhdr_t;
 171
 172 typedef enum {
 173
 174         /* RFC 2960 Section 3.3.5 */
 175         SCTP_PARAM_HEARTBEAT_INFO               = __constant_htons(1),
 176         /* RFC 2960 Section 3.3.2.1 */
 177         SCTP_PARAM_IPV4_ADDRESS                 = __constant_htons(5),
 178         SCTP_PARAM_IPV6_ADDRESS                 = __constant_htons(6),
 179         SCTP_PARAM_STATE_COOKIE                 = __constant_htons(7),
 180         SCTP_PARAM_UNRECOGNIZED_PARAMETERS      = __constant_htons(8),
 181         SCTP_PARAM_COOKIE_PRESERVATIVE          = __constant_htons(9),
 182         SCTP_PARAM_HOST_NAME_ADDRESS            = __constant_htons(11),
 183         SCTP_PARAM_SUPPORTED_ADDRESS_TYPES      = __constant_htons(12),
 184         SCTP_PARAM_ECN_CAPABLE                  = __constant_htons(0x8000),
 185
 186         /* AUTH Extension Section 3 */
 187         SCTP_PARAM_RANDOM                       = __constant_htons(0x8002),
 188         SCTP_PARAM_CHUNKS                       = __constant_htons(0x8003),
 189         SCTP_PARAM_HMAC_ALGO                    = __constant_htons(0x8004),
 190
 191         /* Add-IP: Supported Extensions, Section 4.2 */
 192         SCTP_PARAM_SUPPORTED_EXT        = __constant_htons(0x8008),
 193
 194         /* PR-SCTP Sec 3.1 */
 195         SCTP_PARAM_FWD_TSN_SUPPORT      = __constant_htons(0xc000),
 196
 197         /* Add-IP Extension. Section 3.2 */
 198         SCTP_PARAM_ADD_IP               = __constant_htons(0xc001),
 199         SCTP_PARAM_DEL_IP               = __constant_htons(0xc002),
 200         SCTP_PARAM_ERR_CAUSE            = __constant_htons(0xc003),
 201         SCTP_PARAM_SET_PRIMARY          = __constant_htons(0xc004),
 202         SCTP_PARAM_SUCCESS_REPORT       = __constant_htons(0xc005),
 203         SCTP_PARAM_ADAPTATION_LAYER_IND = __constant_htons(0xc006),
 204
 205 } sctp_param_t; /* enum */
 206
 207
 208 /* RFC 2960 Section 3.2.1
 209  *  The Parameter Types are encoded such that the highest-order two bits
 210  *  specify the action that must be taken if the processing endpoint does
 211  *  not recognize the Parameter Type.
 212  *
 213  */
 214 typedef enum {
 215         SCTP_PARAM_ACTION_DISCARD     = __constant_htons(0x0000),
 216         SCTP_PARAM_ACTION_DISCARD_ERR = __constant_htons(0x4000),
 217         SCTP_PARAM_ACTION_SKIP        = __constant_htons(0x8000),
 218         SCTP_PARAM_ACTION_SKIP_ERR    = __constant_htons(0xc000),
 219 } sctp_param_action_t;
 220
 221 enum { SCTP_PARAM_ACTION_MASK = __constant_htons(0xc000), };
 222
 223 /* RFC 2960 Section 3.3.1 Payload Data (DATA) (0) */
 224
 225 typedef struct sctp_datahdr {
 226         __be32 tsn;
 227         __be16 stream;
 228         __be16 ssn;
 229         __be32 ppid;
 230         __u8  payload[0];
 231 } __attribute__((packed)) sctp_datahdr_t;
 232
 233 typedef struct sctp_data_chunk {
 234         sctp_chunkhdr_t chunk_hdr;
 235         sctp_datahdr_t  data_hdr;
 236 } __attribute__((packed)) sctp_data_chunk_t;
 237
 238 /* DATA Chuck Specific Flags */
 239 enum {
 240         SCTP_DATA_MIDDLE_FRAG   = 0x00,
 241         SCTP_DATA_LAST_FRAG     = 0x01,
 242         SCTP_DATA_FIRST_FRAG    = 0x02,
 243         SCTP_DATA_NOT_FRAG      = 0x03,
 244         SCTP_DATA_UNORDERED     = 0x04,
 245 };
 246 enum { SCTP_DATA_FRAG_MASK = 0x03, };
 247
 248
 249 /* RFC 2960 Section 3.3.2 Initiation (INIT) (1)
 250  *
 251  *  This chunk is used to initiate a SCTP association between two
 252  *  endpoints.
 253  */
 254 typedef struct sctp_inithdr {
 255         __be32 init_tag;
 256         __be32 a_rwnd;
 257         __be16 num_outbound_streams;
 258         __be16 num_inbound_streams;
 259         __be32 initial_tsn;
 260         __u8  params[0];
 261 } __attribute__((packed)) sctp_inithdr_t;
 262
 263 typedef struct sctp_init_chunk {
 264         sctp_chunkhdr_t chunk_hdr;
 265         sctp_inithdr_t init_hdr;
 266 } __attribute__((packed)) sctp_init_chunk_t;
 267
 268
 269 /* Section 3.3.2.1. IPv4 Address Parameter (5) */
 270 typedef struct sctp_ipv4addr_param {
 271         sctp_paramhdr_t param_hdr;
 272         struct in_addr  addr;
 273 } __attribute__((packed)) sctp_ipv4addr_param_t;
 274
 275 /* Section 3.3.2.1. IPv6 Address Parameter (6) */
 276 typedef struct sctp_ipv6addr_param {
 277         sctp_paramhdr_t param_hdr;
 278         struct in6_addr addr;
 279 } __attribute__((packed)) sctp_ipv6addr_param_t;
 280
 281 /* Section 3.3.2.1 Cookie Preservative (9) */
 282 typedef struct sctp_cookie_preserve_param {
 283         sctp_paramhdr_t param_hdr;
 284         __be32          lifespan_increment;
 285 } __attribute__((packed)) sctp_cookie_preserve_param_t;
 286
 287 /* Section 3.3.2.1 Host Name Address (11) */
 288 typedef struct sctp_hostname_param {
 289         sctp_paramhdr_t param_hdr;
 290         uint8_t hostname[0];
 291 } __attribute__((packed)) sctp_hostname_param_t;
 292
 293 /* Section 3.3.2.1 Supported Address Types (12) */
 294 typedef struct sctp_supported_addrs_param {
 295         sctp_paramhdr_t param_hdr;
 296         __be16 types[0];
 297 } __attribute__((packed)) sctp_supported_addrs_param_t;
 298
 299 /* Appendix A. ECN Capable (32768) */
 300 typedef struct sctp_ecn_capable_param {
 301         sctp_paramhdr_t param_hdr;
 302 } __attribute__((packed)) sctp_ecn_capable_param_t;
 303
 304 /* ADDIP Section 3.2.6 Adaptation Layer Indication */
 305 typedef struct sctp_adaptation_ind_param {
 306         struct sctp_paramhdr param_hdr;
 307         __be32 adaptation_ind;
 308 } __attribute__((packed)) sctp_adaptation_ind_param_t;
 309
 310 /* ADDIP Section 4.2.7 Supported Extensions Parameter */
 311 typedef struct sctp_supported_ext_param {
 312         struct sctp_paramhdr param_hdr;
 313         __u8 chunks[0];
 314 } __attribute__((packed)) sctp_supported_ext_param_t;
 315
 316 /* AUTH Section 3.1 Random */
 317 typedef struct sctp_random_param {
 318         sctp_paramhdr_t param_hdr;
 319         __u8 random_val[0];
 320 } __attribute__((packed)) sctp_random_param_t;
 321
 322 /* AUTH Section 3.2 Chunk List */
 323 typedef struct sctp_chunks_param {
 324         sctp_paramhdr_t param_hdr;
 325         __u8 chunks[0];
 326 } __attribute__((packed)) sctp_chunks_param_t;
 327
 328 /* AUTH Section 3.3 HMAC Algorithm */
 329 typedef struct sctp_hmac_algo_param {
 330         sctp_paramhdr_t param_hdr;
 331         __be16 hmac_ids[0];
 332 } __attribute__((packed)) sctp_hmac_algo_param_t;
 333
 334 /* RFC 2960.  Section 3.3.3 Initiation Acknowledgement (INIT ACK) (2):
 335  *   The INIT ACK chunk is used to acknowledge the initiation of an SCTP
 336  *   association.
 337  */
 338 typedef sctp_init_chunk_t sctp_initack_chunk_t;
 339
 340 /* Section 3.3.3.1 State Cookie (7) */
 341 typedef struct sctp_cookie_param {
 342         sctp_paramhdr_t p;
 343         __u8 body[0];
 344 } __attribute__((packed)) sctp_cookie_param_t;
 345
 346 /* Section 3.3.3.1 Unrecognized Parameters (8) */
 347 typedef struct sctp_unrecognized_param {
 348         sctp_paramhdr_t param_hdr;
 349         sctp_paramhdr_t unrecognized;
 350 } __attribute__((packed)) sctp_unrecognized_param_t;
 351
 352
 353
 354 /*
 355  * 3.3.4 Selective Acknowledgement (SACK) (3):
 356  *
 357  *  This chunk is sent to the peer endpoint to acknowledge received DATA
 358  *  chunks and to inform the peer endpoint of gaps in the received
 359  *  subsequences of DATA chunks as represented by their TSNs.
 360  */
 361
 362 typedef struct sctp_gap_ack_block {
 363         __be16 start;
 364         __be16 end;
 365 } __attribute__((packed)) sctp_gap_ack_block_t;
 366
 367 typedef __be32 sctp_dup_tsn_t;
 368
 369 typedef union {
 370         sctp_gap_ack_block_t    gab;
 371         sctp_dup_tsn_t          dup;
 372 } sctp_sack_variable_t;
 373
 374 typedef struct sctp_sackhdr {
 375         __be32 cum_tsn_ack;
 376         __be32 a_rwnd;
 377         __be16 num_gap_ack_blocks;
 378         __be16 num_dup_tsns;
 379         sctp_sack_variable_t variable[0];
 380 } __attribute__((packed)) sctp_sackhdr_t;
 381
 382 typedef struct sctp_sack_chunk {
 383         sctp_chunkhdr_t chunk_hdr;
 384         sctp_sackhdr_t sack_hdr;
 385 } __attribute__((packed)) sctp_sack_chunk_t;
 386
 387
 388 /* RFC 2960.  Section 3.3.5 Heartbeat Request (HEARTBEAT) (4):
 389  *
 390  *  An endpoint should send this chunk to its peer endpoint to probe the
 391  *  reachability of a particular destination transport address defined in
 392  *  the present association.
 393  */
 394
 395 typedef struct sctp_heartbeathdr {
 396         sctp_paramhdr_t info;
 397 } __attribute__((packed)) sctp_heartbeathdr_t;
 398
 399 typedef struct sctp_heartbeat_chunk {
 400         sctp_chunkhdr_t chunk_hdr;
 401         sctp_heartbeathdr_t hb_hdr;
 402 } __attribute__((packed)) sctp_heartbeat_chunk_t;
 403
 404
 405 /* For the abort and shutdown ACK we must carry the init tag in the
 406  * common header. Just the common header is all that is needed with a
 407  * chunk descriptor.
 408  */
 409 typedef struct sctp_abort_chunk {
 410         sctp_chunkhdr_t uh;
 411 } __attribute__((packed)) sctp_abort_chunk_t;
 412
 413
 414 /* For the graceful shutdown we must carry the tag (in common header)
 415  * and the highest consecutive acking value.
 416  */
 417 typedef struct sctp_shutdownhdr {
 418         __be32 cum_tsn_ack;
 419 } __attribute__((packed)) sctp_shutdownhdr_t;
 420
 421 struct sctp_shutdown_chunk_t {
 422         sctp_chunkhdr_t    chunk_hdr;
 423         sctp_shutdownhdr_t shutdown_hdr;
 424 } __attribute__ ((packed));
 425
 426 /* RFC 2960.  Section 3.3.10 Operation Error (ERROR) (9) */
 427
 428 typedef struct sctp_errhdr {
 429         __be16 cause;
 430         __be16 length;
 431         __u8  variable[0];
 432 } __attribute__((packed)) sctp_errhdr_t;
 433
 434 typedef struct sctp_operr_chunk {
 435         sctp_chunkhdr_t chunk_hdr;
 436         sctp_errhdr_t   err_hdr;
 437 } __attribute__((packed)) sctp_operr_chunk_t;
 438
 439 /* RFC 2960 3.3.10 - Operation Error
 440  *
 441  * Cause Code: 16 bits (unsigned integer)
 442  *
 443  *     Defines the type of error conditions being reported.
 444  *    Cause Code
 445  *     Value           Cause Code
 446  *     ---------      ----------------
 447  *      1              Invalid Stream Identifier
 448  *      2              Missing Mandatory Parameter
 449  *      3              Stale Cookie Error
 450  *      4              Out of Resource
 451  *      5              Unresolvable Address
 452  *      6              Unrecognized Chunk Type
 453  *      7              Invalid Mandatory Parameter
 454  *      8              Unrecognized Parameters
 455  *      9              No User Data
 456  *     10              Cookie Received While Shutting Down
 457  */
 458 typedef enum {
 459
 460         SCTP_ERROR_NO_ERROR        = __constant_htons(0x00),
 461         SCTP_ERROR_INV_STRM        = __constant_htons(0x01),
 462         SCTP_ERROR_MISS_PARAM      = __constant_htons(0x02),
 463         SCTP_ERROR_STALE_COOKIE    = __constant_htons(0x03),
 464         SCTP_ERROR_NO_RESOURCE     = __constant_htons(0x04),
 465         SCTP_ERROR_DNS_FAILED      = __constant_htons(0x05),
 466         SCTP_ERROR_UNKNOWN_CHUNK   = __constant_htons(0x06),
 467         SCTP_ERROR_INV_PARAM       = __constant_htons(0x07),
 468         SCTP_ERROR_UNKNOWN_PARAM   = __constant_htons(0x08),
 469         SCTP_ERROR_NO_DATA         = __constant_htons(0x09),
 470         SCTP_ERROR_COOKIE_IN_SHUTDOWN = __constant_htons(0x0a),
 471
 472
 473         /* SCTP Implementation Guide:
 474          *  11  Restart of an association with new addresses
 475          *  12  User Initiated Abort
 476          *  13  Protocol Violation
 477          */
 478
 479         SCTP_ERROR_RESTART         = __constant_htons(0x0b),
 480         SCTP_ERROR_USER_ABORT      = __constant_htons(0x0c),
 481         SCTP_ERROR_PROTO_VIOLATION = __constant_htons(0x0d),
 482
 483         /* ADDIP Section 3.3  New Error Causes
 484          *
 485          * Four new Error Causes are added to the SCTP Operational Errors,
 486          * primarily for use in the ASCONF-ACK chunk.
 487          *
 488          * Value          Cause Code
 489          * ---------      ----------------
 490          * 0x0100          Request to Delete Last Remaining IP Address.
 491          * 0x0101          Operation Refused Due to Resource Shortage.
 492          * 0x0102          Request to Delete Source IP Address.
 493          * 0x0103          Association Aborted due to illegal ASCONF-ACK
 494          * 0x0104          Request refused - no authorization.
 495          */
 496         SCTP_ERROR_DEL_LAST_IP  = __constant_htons(0x0100),
 497         SCTP_ERROR_RSRC_LOW     = __constant_htons(0x0101),
 498         SCTP_ERROR_DEL_SRC_IP   = __constant_htons(0x0102),
 499         SCTP_ERROR_ASCONF_ACK   = __constant_htons(0x0103),
 500         SCTP_ERROR_REQ_REFUSED  = __constant_htons(0x0104),
 501
 502         /* AUTH Section 4.  New Error Cause
 503          *
 504          * This section defines a new error cause that will be sent if an AUTH
 505          * chunk is received with an unsupported HMAC identifier.
 506          * illustrates the new error cause.
 507          *
 508          * Cause Code      Error Cause Name
 509          * --------------------------------------------------------------
 510          * 0x0105          Unsupported HMAC Identifier
 511          */
 512          SCTP_ERROR_UNSUP_HMAC  = __constant_htons(0x0105)
 513 } sctp_error_t;
 514
 515
 516
 517 /* RFC 2960.  Appendix A.  Explicit Congestion Notification.
 518  *   Explicit Congestion Notification Echo (ECNE) (12)
 519  */
 520 typedef struct sctp_ecnehdr {
 521         __be32 lowest_tsn;
 522 } sctp_ecnehdr_t;
 523
 524 typedef struct sctp_ecne_chunk {
 525         sctp_chunkhdr_t chunk_hdr;
 526         sctp_ecnehdr_t ence_hdr;
 527 } __attribute__((packed)) sctp_ecne_chunk_t;
 528
 529 /* RFC 2960.  Appendix A.  Explicit Congestion Notification.
 530  *   Congestion Window Reduced (CWR) (13)
 531  */
 532 typedef struct sctp_cwrhdr {
 533         __be32 lowest_tsn;
 534 } sctp_cwrhdr_t;
 535
 536 typedef struct sctp_cwr_chunk {
 537         sctp_chunkhdr_t chunk_hdr;
 538         sctp_cwrhdr_t cwr_hdr;
 539 } __attribute__((packed)) sctp_cwr_chunk_t;
 540
 541 /* PR-SCTP
 542  * 3.2 Forward Cumulative TSN Chunk Definition (FORWARD TSN)
 543  *
 544  * Forward Cumulative TSN chunk has the following format:
 545  *
 546  *        0                   1                   2                   3
 547  *        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
 548  *      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 549  *      |   Type = 192  |  Flags = 0x00 |        Length = Variable      |
 550  *      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 551  *      |                      New Cumulative TSN                       |
 552  *      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 553  *      |         Stream-1              |       Stream Sequence-1       |
 554  *      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 555  *      \                                                               /
 556  *      /                                                               \
 557  *      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 558  *      |         Stream-N              |       Stream Sequence-N       |
 559  *      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 560  *
 561  *      Chunk Flags:
 562  *
 563  *        Set to all zeros on transmit and ignored on receipt.
 564  *
 565  *      New Cumulative TSN: 32 bit u_int
 566  *
 567  *       This indicates the new cumulative TSN to the data receiver. Upon
 568  *       the reception of this value, the data receiver MUST consider
 569  *       any missing TSNs earlier than or equal to this value as received
 570  *       and stop reporting them as gaps in any subsequent SACKs.
 571  *
 572  *      Stream-N: 16 bit u_int
 573  *
 574  *       This field holds a stream number that was skipped by this
 575  *       FWD-TSN.
 576  *
 577  *      Stream Sequence-N: 16 bit u_int
 578  *       This field holds the sequence number associated with the stream
 579  *       that was skipped. The stream sequence field holds the largest stream
 580  *       sequence number in this stream being skipped.  The receiver of
 581  *       the FWD-TSN's can use the Stream-N and Stream Sequence-N fields
 582  *       to enable delivery of any stranded TSN's that remain on the stream
 583  *       re-ordering queues. This field MUST NOT report TSN's corresponding
 584  *       to DATA chunk that are marked as unordered. For ordered DATA
 585  *       chunks this field MUST be filled in.
 586  */
 587 struct sctp_fwdtsn_skip {
 588         __be16 stream;
 589         __be16 ssn;
 590 } __attribute__((packed));
 591
 592 struct sctp_fwdtsn_hdr {
 593         __be32 new_cum_tsn;
 594         struct sctp_fwdtsn_skip skip[0];
 595 } __attribute((packed));
 596
 597 struct sctp_fwdtsn_chunk {
 598         struct sctp_chunkhdr chunk_hdr;
 599         struct sctp_fwdtsn_hdr fwdtsn_hdr;
 600 } __attribute((packed));
 601
 602
 603 /* ADDIP
 604  * Section 3.1.1 Address Configuration Change Chunk (ASCONF)
 605  *
 606  *      Serial Number: 32 bits (unsigned integer)
 607  *      This value represents a Serial Number for the ASCONF Chunk. The
 608  *      valid range of Serial Number is from 0 to 2^32-1.
 609  *      Serial Numbers wrap back to 0 after reaching 2^32 -1.
 610  *
 611  *      Address Parameter: 8 or 20 bytes (depending on type)
 612  *      The address is an address of the sender of the ASCONF chunk,
 613  *      the address MUST be considered part of the association by the
 614  *      peer endpoint. This field may be used by the receiver of the
 615  *      ASCONF to help in finding the association. This parameter MUST
 616  *      be present in every ASCONF message i.e. it is a mandatory TLV
 617  *      parameter.
 618  *
 619  *      ASCONF Parameter: TLV format
 620  *      Each Address configuration change is represented by a TLV
 621  *      parameter as defined in Section 3.2. One or more requests may
 622  *      be present in an ASCONF Chunk.
 623  *
 624  * Section 3.1.2 Address Configuration Acknowledgement Chunk (ASCONF-ACK)
 625  *
 626  *      Serial Number: 32 bits (unsigned integer)
 627  *      This value represents the Serial Number for the received ASCONF
 628  *      Chunk that is acknowledged by this chunk. This value is copied
 629  *      from the received ASCONF Chunk.
 630  *
 631  *      ASCONF Parameter Response: TLV format
 632  *      The ASCONF Parameter Response is used in the ASCONF-ACK to
 633  *      report status of ASCONF processing.
 634  */
 635 typedef struct sctp_addip_param {
 636         sctp_paramhdr_t param_hdr;
 637         __be32          crr_id;
 638 } __attribute__((packed)) sctp_addip_param_t;
 639
 640 typedef struct sctp_addiphdr {
 641         __be32  serial;
 642         __u8    params[0];
 643 } __attribute__((packed)) sctp_addiphdr_t;
 644
 645 typedef struct sctp_addip_chunk {
 646         sctp_chunkhdr_t chunk_hdr;
 647         sctp_addiphdr_t addip_hdr;
 648 } __attribute__((packed)) sctp_addip_chunk_t;
 649
 650 /* AUTH
 651  * Section 4.1  Authentication Chunk (AUTH)
 652  *
 653  *   This chunk is used to hold the result of the HMAC calculation.
 654  *
 655  *    0                   1                   2                   3
 656  *    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
 657  *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 658  *   | Type = 0x0F   |   Flags=0     |             Length            |
 659  *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 660  *   |     Shared Key Identifier     |   HMAC Identifier             |
 661  *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 662  *   |                                                               |
 663  *   \                             HMAC                              /
 664  *   /                                                               \
 665  *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 666  *
 667  *   Type: 1 byte (unsigned integer)
 668  *      This value MUST be set to 0x0F for  all AUTH-chunks.
 669  *
 670  *   Flags: 1 byte (unsigned integer)
 671  *      Set to zero on transmit and ignored on receipt.
 672  *
 673  *   Length: 2 bytes (unsigned integer)
 674  *      This value holds the length of the HMAC in bytes plus 8.
 675  *
 676  *  Shared Key Identifier: 2 bytes (unsigned integer)
 677  *      This value describes which endpoint pair shared key is used.
 678  *
 679  *   HMAC Identifier: 2 bytes (unsigned integer)
 680  *      This value describes which message digest is being used.  Table 2
 681  *      shows the currently defined values.
 682  *
 683  *    The following Table 2 shows the currently defined values for HMAC
 684  *       identifiers.
 685  *
 686  *       +-----------------+--------------------------+
 687  *       | HMAC Identifier | Message Digest Algorithm |
 688  *       +-----------------+--------------------------+
 689  *       | 0               | Reserved                 |
 690  *       | 1               | SHA-1 defined in [8]     |
 691  *       | 2               | Reserved                 |
 692  *       | 3               | SHA-256 defined in [8]   |
 693  *       +-----------------+--------------------------+
 694  *
 695  *
 696  *   HMAC: n bytes (unsigned integer) This hold the result of the HMAC
 697  *      calculation.
 698  */
 699 typedef struct sctp_authhdr {
 700         __be16 shkey_id;
 701         __be16 hmac_id;
 702         __u8   hmac[0];
 703 } __attribute__((packed)) sctp_authhdr_t;
 704
 705 typedef struct sctp_auth_chunk {
 706         sctp_chunkhdr_t chunk_hdr;
 707         sctp_authhdr_t auth_hdr;
 708 } __attribute__((packed)) sctp_auth_chunk_t;
 709
 710 #endif /* __LINUX_SCTP_H__ */