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 * This SCTP 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 * This SCTP 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, see 27 * <http://www.gnu.org/licenses/>. 28 * 29 * Please send any bug reports or fixes you make to the 30 * email address(es): 31 * lksctp developers <[email protected]> 32 * 33 * Or submit a bug report through the following website: 34 * http://www.sf.net/projects/lksctp 35 * 36 * Written or modified by: 37 * La Monte H.P. Yarroll <[email protected]> 38 * Karl Knutson <[email protected]> 39 * Jon Grimm <[email protected]> 40 * Xingang Guo <[email protected]> 41 * [email protected] 42 * [email protected] 43 * [email protected] 44 * Sridhar Samudrala <[email protected]> 45 * Kevin Gao <[email protected]> 46 * 47 * Any bugs reported given to us we will try to fix... any fixes shared will 48 * be incorporated into the next SCTP release. 49 */ 50 #ifndef __LINUX_SCTP_H__ 51 #define __LINUX_SCTP_H__ 52 53 #include <linux/in.h> /* We need in_addr. */ 54 #include <linux/in6.h> /* We need in6_addr. */ 55 #include <linux/skbuff.h> 56 57 #include <uapi/linux/sctp.h> 58 59 /* Section 3.1. SCTP Common Header Format */ 60 typedef struct sctphdr { 61 __be16 source; 62 __be16 dest; 63 __be32 vtag; 64 __le32 checksum; 65 } __packed sctp_sctphdr_t; 66 67 static inline struct sctphdr *sctp_hdr(const struct sk_buff *skb) 68 { 69 return (struct sctphdr *)skb_transport_header(skb); 70 } 71 72 /* Section 3.2. Chunk Field Descriptions. */ 73 typedef struct sctp_chunkhdr { 74 __u8 type; 75 __u8 flags; 76 __be16 length; 77 } __packed sctp_chunkhdr_t; 78 79 80 /* Section 3.2. Chunk Type Values. 81 * [Chunk Type] identifies the type of information contained in the Chunk 82 * Value field. It takes a value from 0 to 254. The value of 255 is 83 * reserved for future use as an extension field. 84 */ 85 typedef enum { 86 SCTP_CID_DATA = 0, 87 SCTP_CID_INIT = 1, 88 SCTP_CID_INIT_ACK = 2, 89 SCTP_CID_SACK = 3, 90 SCTP_CID_HEARTBEAT = 4, 91 SCTP_CID_HEARTBEAT_ACK = 5, 92 SCTP_CID_ABORT = 6, 93 SCTP_CID_SHUTDOWN = 7, 94 SCTP_CID_SHUTDOWN_ACK = 8, 95 SCTP_CID_ERROR = 9, 96 SCTP_CID_COOKIE_ECHO = 10, 97 SCTP_CID_COOKIE_ACK = 11, 98 SCTP_CID_ECN_ECNE = 12, 99 SCTP_CID_ECN_CWR = 13, 100 SCTP_CID_SHUTDOWN_COMPLETE = 14, 101 102 /* AUTH Extension Section 4.1 */ 103 SCTP_CID_AUTH = 0x0F, 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 } __packed sctp_paramhdr_t; 168 169 typedef enum { 170 171 /* RFC 2960 Section 3.3.5 */ 172 SCTP_PARAM_HEARTBEAT_INFO = cpu_to_be16(1), 173 /* RFC 2960 Section 3.3.2.1 */ 174 SCTP_PARAM_IPV4_ADDRESS = cpu_to_be16(5), 175 SCTP_PARAM_IPV6_ADDRESS = cpu_to_be16(6), 176 SCTP_PARAM_STATE_COOKIE = cpu_to_be16(7), 177 SCTP_PARAM_UNRECOGNIZED_PARAMETERS = cpu_to_be16(8), 178 SCTP_PARAM_COOKIE_PRESERVATIVE = cpu_to_be16(9), 179 SCTP_PARAM_HOST_NAME_ADDRESS = cpu_to_be16(11), 180 SCTP_PARAM_SUPPORTED_ADDRESS_TYPES = cpu_to_be16(12), 181 SCTP_PARAM_ECN_CAPABLE = cpu_to_be16(0x8000), 182 183 /* AUTH Extension Section 3 */ 184 SCTP_PARAM_RANDOM = cpu_to_be16(0x8002), 185 SCTP_PARAM_CHUNKS = cpu_to_be16(0x8003), 186 SCTP_PARAM_HMAC_ALGO = cpu_to_be16(0x8004), 187 188 /* Add-IP: Supported Extensions, Section 4.2 */ 189 SCTP_PARAM_SUPPORTED_EXT = cpu_to_be16(0x8008), 190 191 /* PR-SCTP Sec 3.1 */ 192 SCTP_PARAM_FWD_TSN_SUPPORT = cpu_to_be16(0xc000), 193 194 /* Add-IP Extension. Section 3.2 */ 195 SCTP_PARAM_ADD_IP = cpu_to_be16(0xc001), 196 SCTP_PARAM_DEL_IP = cpu_to_be16(0xc002), 197 SCTP_PARAM_ERR_CAUSE = cpu_to_be16(0xc003), 198 SCTP_PARAM_SET_PRIMARY = cpu_to_be16(0xc004), 199 SCTP_PARAM_SUCCESS_REPORT = cpu_to_be16(0xc005), 200 SCTP_PARAM_ADAPTATION_LAYER_IND = cpu_to_be16(0xc006), 201 202 } sctp_param_t; /* enum */ 203 204 205 /* RFC 2960 Section 3.2.1 206 * The Parameter Types are encoded such that the highest-order two bits 207 * specify the action that must be taken if the processing endpoint does 208 * not recognize the Parameter Type. 209 * 210 */ 211 typedef enum { 212 SCTP_PARAM_ACTION_DISCARD = cpu_to_be16(0x0000), 213 SCTP_PARAM_ACTION_DISCARD_ERR = cpu_to_be16(0x4000), 214 SCTP_PARAM_ACTION_SKIP = cpu_to_be16(0x8000), 215 SCTP_PARAM_ACTION_SKIP_ERR = cpu_to_be16(0xc000), 216 } sctp_param_action_t; 217 218 enum { SCTP_PARAM_ACTION_MASK = cpu_to_be16(0xc000), }; 219 220 /* RFC 2960 Section 3.3.1 Payload Data (DATA) (0) */ 221 222 typedef struct sctp_datahdr { 223 __be32 tsn; 224 __be16 stream; 225 __be16 ssn; 226 __be32 ppid; 227 __u8 payload[0]; 228 } __packed sctp_datahdr_t; 229 230 typedef struct sctp_data_chunk { 231 sctp_chunkhdr_t chunk_hdr; 232 sctp_datahdr_t data_hdr; 233 } __packed sctp_data_chunk_t; 234 235 /* DATA Chuck Specific Flags */ 236 enum { 237 SCTP_DATA_MIDDLE_FRAG = 0x00, 238 SCTP_DATA_LAST_FRAG = 0x01, 239 SCTP_DATA_FIRST_FRAG = 0x02, 240 SCTP_DATA_NOT_FRAG = 0x03, 241 SCTP_DATA_UNORDERED = 0x04, 242 SCTP_DATA_SACK_IMM = 0x08, 243 }; 244 enum { SCTP_DATA_FRAG_MASK = 0x03, }; 245 246 247 /* RFC 2960 Section 3.3.2 Initiation (INIT) (1) 248 * 249 * This chunk is used to initiate a SCTP association between two 250 * endpoints. 251 */ 252 typedef struct sctp_inithdr { 253 __be32 init_tag; 254 __be32 a_rwnd; 255 __be16 num_outbound_streams; 256 __be16 num_inbound_streams; 257 __be32 initial_tsn; 258 __u8 params[0]; 259 } __packed sctp_inithdr_t; 260 261 typedef struct sctp_init_chunk { 262 sctp_chunkhdr_t chunk_hdr; 263 sctp_inithdr_t init_hdr; 264 } __packed sctp_init_chunk_t; 265 266 267 /* Section 3.3.2.1. IPv4 Address Parameter (5) */ 268 typedef struct sctp_ipv4addr_param { 269 sctp_paramhdr_t param_hdr; 270 struct in_addr addr; 271 } __packed sctp_ipv4addr_param_t; 272 273 /* Section 3.3.2.1. IPv6 Address Parameter (6) */ 274 typedef struct sctp_ipv6addr_param { 275 sctp_paramhdr_t param_hdr; 276 struct in6_addr addr; 277 } __packed sctp_ipv6addr_param_t; 278 279 /* Section 3.3.2.1 Cookie Preservative (9) */ 280 typedef struct sctp_cookie_preserve_param { 281 sctp_paramhdr_t param_hdr; 282 __be32 lifespan_increment; 283 } __packed sctp_cookie_preserve_param_t; 284 285 /* Section 3.3.2.1 Host Name Address (11) */ 286 typedef struct sctp_hostname_param { 287 sctp_paramhdr_t param_hdr; 288 uint8_t hostname[0]; 289 } __packed sctp_hostname_param_t; 290 291 /* Section 3.3.2.1 Supported Address Types (12) */ 292 typedef struct sctp_supported_addrs_param { 293 sctp_paramhdr_t param_hdr; 294 __be16 types[0]; 295 } __packed sctp_supported_addrs_param_t; 296 297 /* Appendix A. ECN Capable (32768) */ 298 typedef struct sctp_ecn_capable_param { 299 sctp_paramhdr_t param_hdr; 300 } __packed sctp_ecn_capable_param_t; 301 302 /* ADDIP Section 3.2.6 Adaptation Layer Indication */ 303 typedef struct sctp_adaptation_ind_param { 304 struct sctp_paramhdr param_hdr; 305 __be32 adaptation_ind; 306 } __packed sctp_adaptation_ind_param_t; 307 308 /* ADDIP Section 4.2.7 Supported Extensions Parameter */ 309 typedef struct sctp_supported_ext_param { 310 struct sctp_paramhdr param_hdr; 311 __u8 chunks[0]; 312 } __packed sctp_supported_ext_param_t; 313 314 /* AUTH Section 3.1 Random */ 315 typedef struct sctp_random_param { 316 sctp_paramhdr_t param_hdr; 317 __u8 random_val[0]; 318 } __packed sctp_random_param_t; 319 320 /* AUTH Section 3.2 Chunk List */ 321 typedef struct sctp_chunks_param { 322 sctp_paramhdr_t param_hdr; 323 __u8 chunks[0]; 324 } __packed sctp_chunks_param_t; 325 326 /* AUTH Section 3.3 HMAC Algorithm */ 327 typedef struct sctp_hmac_algo_param { 328 sctp_paramhdr_t param_hdr; 329 __be16 hmac_ids[0]; 330 } __packed sctp_hmac_algo_param_t; 331 332 /* RFC 2960. Section 3.3.3 Initiation Acknowledgement (INIT ACK) (2): 333 * The INIT ACK chunk is used to acknowledge the initiation of an SCTP 334 * association. 335 */ 336 typedef sctp_init_chunk_t sctp_initack_chunk_t; 337 338 /* Section 3.3.3.1 State Cookie (7) */ 339 typedef struct sctp_cookie_param { 340 sctp_paramhdr_t p; 341 __u8 body[0]; 342 } __packed sctp_cookie_param_t; 343 344 /* Section 3.3.3.1 Unrecognized Parameters (8) */ 345 typedef struct sctp_unrecognized_param { 346 sctp_paramhdr_t param_hdr; 347 sctp_paramhdr_t unrecognized; 348 } __packed sctp_unrecognized_param_t; 349 350 351 352 /* 353 * 3.3.4 Selective Acknowledgement (SACK) (3): 354 * 355 * This chunk is sent to the peer endpoint to acknowledge received DATA 356 * chunks and to inform the peer endpoint of gaps in the received 357 * subsequences of DATA chunks as represented by their TSNs. 358 */ 359 360 typedef struct sctp_gap_ack_block { 361 __be16 start; 362 __be16 end; 363 } __packed sctp_gap_ack_block_t; 364 365 typedef __be32 sctp_dup_tsn_t; 366 367 typedef union { 368 sctp_gap_ack_block_t gab; 369 sctp_dup_tsn_t dup; 370 } sctp_sack_variable_t; 371 372 typedef struct sctp_sackhdr { 373 __be32 cum_tsn_ack; 374 __be32 a_rwnd; 375 __be16 num_gap_ack_blocks; 376 __be16 num_dup_tsns; 377 sctp_sack_variable_t variable[0]; 378 } __packed sctp_sackhdr_t; 379 380 typedef struct sctp_sack_chunk { 381 sctp_chunkhdr_t chunk_hdr; 382 sctp_sackhdr_t sack_hdr; 383 } __packed sctp_sack_chunk_t; 384 385 386 /* RFC 2960. Section 3.3.5 Heartbeat Request (HEARTBEAT) (4): 387 * 388 * An endpoint should send this chunk to its peer endpoint to probe the 389 * reachability of a particular destination transport address defined in 390 * the present association. 391 */ 392 393 typedef struct sctp_heartbeathdr { 394 sctp_paramhdr_t info; 395 } __packed sctp_heartbeathdr_t; 396 397 typedef struct sctp_heartbeat_chunk { 398 sctp_chunkhdr_t chunk_hdr; 399 sctp_heartbeathdr_t hb_hdr; 400 } __packed sctp_heartbeat_chunk_t; 401 402 403 /* For the abort and shutdown ACK we must carry the init tag in the 404 * common header. Just the common header is all that is needed with a 405 * chunk descriptor. 406 */ 407 typedef struct sctp_abort_chunk { 408 sctp_chunkhdr_t uh; 409 } __packed sctp_abort_chunk_t; 410 411 412 /* For the graceful shutdown we must carry the tag (in common header) 413 * and the highest consecutive acking value. 414 */ 415 typedef struct sctp_shutdownhdr { 416 __be32 cum_tsn_ack; 417 } __packed sctp_shutdownhdr_t; 418 419 struct sctp_shutdown_chunk_t { 420 sctp_chunkhdr_t chunk_hdr; 421 sctp_shutdownhdr_t shutdown_hdr; 422 } __packed; 423 424 /* RFC 2960. Section 3.3.10 Operation Error (ERROR) (9) */ 425 426 typedef struct sctp_errhdr { 427 __be16 cause; 428 __be16 length; 429 __u8 variable[0]; 430 } __packed sctp_errhdr_t; 431 432 typedef struct sctp_operr_chunk { 433 sctp_chunkhdr_t chunk_hdr; 434 sctp_errhdr_t err_hdr; 435 } __packed sctp_operr_chunk_t; 436 437 /* RFC 2960 3.3.10 - Operation Error 438 * 439 * Cause Code: 16 bits (unsigned integer) 440 * 441 * Defines the type of error conditions being reported. 442 * Cause Code 443 * Value Cause Code 444 * --------- ---------------- 445 * 1 Invalid Stream Identifier 446 * 2 Missing Mandatory Parameter 447 * 3 Stale Cookie Error 448 * 4 Out of Resource 449 * 5 Unresolvable Address 450 * 6 Unrecognized Chunk Type 451 * 7 Invalid Mandatory Parameter 452 * 8 Unrecognized Parameters 453 * 9 No User Data 454 * 10 Cookie Received While Shutting Down 455 */ 456 typedef enum { 457 458 SCTP_ERROR_NO_ERROR = cpu_to_be16(0x00), 459 SCTP_ERROR_INV_STRM = cpu_to_be16(0x01), 460 SCTP_ERROR_MISS_PARAM = cpu_to_be16(0x02), 461 SCTP_ERROR_STALE_COOKIE = cpu_to_be16(0x03), 462 SCTP_ERROR_NO_RESOURCE = cpu_to_be16(0x04), 463 SCTP_ERROR_DNS_FAILED = cpu_to_be16(0x05), 464 SCTP_ERROR_UNKNOWN_CHUNK = cpu_to_be16(0x06), 465 SCTP_ERROR_INV_PARAM = cpu_to_be16(0x07), 466 SCTP_ERROR_UNKNOWN_PARAM = cpu_to_be16(0x08), 467 SCTP_ERROR_NO_DATA = cpu_to_be16(0x09), 468 SCTP_ERROR_COOKIE_IN_SHUTDOWN = cpu_to_be16(0x0a), 469 470 471 /* SCTP Implementation Guide: 472 * 11 Restart of an association with new addresses 473 * 12 User Initiated Abort 474 * 13 Protocol Violation 475 */ 476 477 SCTP_ERROR_RESTART = cpu_to_be16(0x0b), 478 SCTP_ERROR_USER_ABORT = cpu_to_be16(0x0c), 479 SCTP_ERROR_PROTO_VIOLATION = cpu_to_be16(0x0d), 480 481 /* ADDIP Section 3.3 New Error Causes 482 * 483 * Four new Error Causes are added to the SCTP Operational Errors, 484 * primarily for use in the ASCONF-ACK chunk. 485 * 486 * Value Cause Code 487 * --------- ---------------- 488 * 0x00A0 Request to Delete Last Remaining IP Address. 489 * 0x00A1 Operation Refused Due to Resource Shortage. 490 * 0x00A2 Request to Delete Source IP Address. 491 * 0x00A3 Association Aborted due to illegal ASCONF-ACK 492 * 0x00A4 Request refused - no authorization. 493 */ 494 SCTP_ERROR_DEL_LAST_IP = cpu_to_be16(0x00A0), 495 SCTP_ERROR_RSRC_LOW = cpu_to_be16(0x00A1), 496 SCTP_ERROR_DEL_SRC_IP = cpu_to_be16(0x00A2), 497 SCTP_ERROR_ASCONF_ACK = cpu_to_be16(0x00A3), 498 SCTP_ERROR_REQ_REFUSED = cpu_to_be16(0x00A4), 499 500 /* AUTH Section 4. New Error Cause 501 * 502 * This section defines a new error cause that will be sent if an AUTH 503 * chunk is received with an unsupported HMAC identifier. 504 * illustrates the new error cause. 505 * 506 * Cause Code Error Cause Name 507 * -------------------------------------------------------------- 508 * 0x0105 Unsupported HMAC Identifier 509 */ 510 SCTP_ERROR_UNSUP_HMAC = cpu_to_be16(0x0105) 511 } sctp_error_t; 512 513 514 515 /* RFC 2960. Appendix A. Explicit Congestion Notification. 516 * Explicit Congestion Notification Echo (ECNE) (12) 517 */ 518 typedef struct sctp_ecnehdr { 519 __be32 lowest_tsn; 520 } sctp_ecnehdr_t; 521 522 typedef struct sctp_ecne_chunk { 523 sctp_chunkhdr_t chunk_hdr; 524 sctp_ecnehdr_t ence_hdr; 525 } __packed sctp_ecne_chunk_t; 526 527 /* RFC 2960. Appendix A. Explicit Congestion Notification. 528 * Congestion Window Reduced (CWR) (13) 529 */ 530 typedef struct sctp_cwrhdr { 531 __be32 lowest_tsn; 532 } sctp_cwrhdr_t; 533 534 typedef struct sctp_cwr_chunk { 535 sctp_chunkhdr_t chunk_hdr; 536 sctp_cwrhdr_t cwr_hdr; 537 } __packed sctp_cwr_chunk_t; 538 539 /* PR-SCTP 540 * 3.2 Forward Cumulative TSN Chunk Definition (FORWARD TSN) 541 * 542 * Forward Cumulative TSN chunk has the following format: 543 * 544 * 0 1 2 3 545 * 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 1 546 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 547 * | Type = 192 | Flags = 0x00 | Length = Variable | 548 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 549 * | New Cumulative TSN | 550 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 551 * | Stream-1 | Stream Sequence-1 | 552 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 553 * \ / 554 * / \ 555 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 556 * | Stream-N | Stream Sequence-N | 557 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 558 * 559 * Chunk Flags: 560 * 561 * Set to all zeros on transmit and ignored on receipt. 562 * 563 * New Cumulative TSN: 32 bit u_int 564 * 565 * This indicates the new cumulative TSN to the data receiver. Upon 566 * the reception of this value, the data receiver MUST consider 567 * any missing TSNs earlier than or equal to this value as received 568 * and stop reporting them as gaps in any subsequent SACKs. 569 * 570 * Stream-N: 16 bit u_int 571 * 572 * This field holds a stream number that was skipped by this 573 * FWD-TSN. 574 * 575 * Stream Sequence-N: 16 bit u_int 576 * This field holds the sequence number associated with the stream 577 * that was skipped. The stream sequence field holds the largest stream 578 * sequence number in this stream being skipped. The receiver of 579 * the FWD-TSN's can use the Stream-N and Stream Sequence-N fields 580 * to enable delivery of any stranded TSN's that remain on the stream 581 * re-ordering queues. This field MUST NOT report TSN's corresponding 582 * to DATA chunk that are marked as unordered. For ordered DATA 583 * chunks this field MUST be filled in. 584 */ 585 struct sctp_fwdtsn_skip { 586 __be16 stream; 587 __be16 ssn; 588 } __packed; 589 590 struct sctp_fwdtsn_hdr { 591 __be32 new_cum_tsn; 592 struct sctp_fwdtsn_skip skip[0]; 593 } __packed; 594 595 struct sctp_fwdtsn_chunk { 596 struct sctp_chunkhdr chunk_hdr; 597 struct sctp_fwdtsn_hdr fwdtsn_hdr; 598 } __packed; 599 600 601 /* ADDIP 602 * Section 3.1.1 Address Configuration Change Chunk (ASCONF) 603 * 604 * Serial Number: 32 bits (unsigned integer) 605 * This value represents a Serial Number for the ASCONF Chunk. The 606 * valid range of Serial Number is from 0 to 2^32-1. 607 * Serial Numbers wrap back to 0 after reaching 2^32 -1. 608 * 609 * Address Parameter: 8 or 20 bytes (depending on type) 610 * The address is an address of the sender of the ASCONF chunk, 611 * the address MUST be considered part of the association by the 612 * peer endpoint. This field may be used by the receiver of the 613 * ASCONF to help in finding the association. This parameter MUST 614 * be present in every ASCONF message i.e. it is a mandatory TLV 615 * parameter. 616 * 617 * ASCONF Parameter: TLV format 618 * Each Address configuration change is represented by a TLV 619 * parameter as defined in Section 3.2. One or more requests may 620 * be present in an ASCONF Chunk. 621 * 622 * Section 3.1.2 Address Configuration Acknowledgement Chunk (ASCONF-ACK) 623 * 624 * Serial Number: 32 bits (unsigned integer) 625 * This value represents the Serial Number for the received ASCONF 626 * Chunk that is acknowledged by this chunk. This value is copied 627 * from the received ASCONF Chunk. 628 * 629 * ASCONF Parameter Response: TLV format 630 * The ASCONF Parameter Response is used in the ASCONF-ACK to 631 * report status of ASCONF processing. 632 */ 633 typedef struct sctp_addip_param { 634 sctp_paramhdr_t param_hdr; 635 __be32 crr_id; 636 } __packed sctp_addip_param_t; 637 638 typedef struct sctp_addiphdr { 639 __be32 serial; 640 __u8 params[0]; 641 } __packed sctp_addiphdr_t; 642 643 typedef struct sctp_addip_chunk { 644 sctp_chunkhdr_t chunk_hdr; 645 sctp_addiphdr_t addip_hdr; 646 } __packed sctp_addip_chunk_t; 647 648 /* AUTH 649 * Section 4.1 Authentication Chunk (AUTH) 650 * 651 * This chunk is used to hold the result of the HMAC calculation. 652 * 653 * 0 1 2 3 654 * 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 1 655 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 656 * | Type = 0x0F | Flags=0 | Length | 657 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 658 * | Shared Key Identifier | HMAC Identifier | 659 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 660 * | | 661 * \ HMAC / 662 * / \ 663 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 664 * 665 * Type: 1 byte (unsigned integer) 666 * This value MUST be set to 0x0F for all AUTH-chunks. 667 * 668 * Flags: 1 byte (unsigned integer) 669 * Set to zero on transmit and ignored on receipt. 670 * 671 * Length: 2 bytes (unsigned integer) 672 * This value holds the length of the HMAC in bytes plus 8. 673 * 674 * Shared Key Identifier: 2 bytes (unsigned integer) 675 * This value describes which endpoint pair shared key is used. 676 * 677 * HMAC Identifier: 2 bytes (unsigned integer) 678 * This value describes which message digest is being used. Table 2 679 * shows the currently defined values. 680 * 681 * The following Table 2 shows the currently defined values for HMAC 682 * identifiers. 683 * 684 * +-----------------+--------------------------+ 685 * | HMAC Identifier | Message Digest Algorithm | 686 * +-----------------+--------------------------+ 687 * | 0 | Reserved | 688 * | 1 | SHA-1 defined in [8] | 689 * | 2 | Reserved | 690 * | 3 | SHA-256 defined in [8] | 691 * +-----------------+--------------------------+ 692 * 693 * 694 * HMAC: n bytes (unsigned integer) This hold the result of the HMAC 695 * calculation. 696 */ 697 typedef struct sctp_authhdr { 698 __be16 shkey_id; 699 __be16 hmac_id; 700 __u8 hmac[0]; 701 } __packed sctp_authhdr_t; 702 703 typedef struct sctp_auth_chunk { 704 sctp_chunkhdr_t chunk_hdr; 705 sctp_authhdr_t auth_hdr; 706 } __packed sctp_auth_chunk_t; 707 708 #endif /* __LINUX_SCTP_H__ */ 709