summaryrefslogtreecommitdiffstats
path: root/include/linux/sctp.h
blob: f4d717b72dddce60e50a6601300c107c16150dec (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
/* SCTP kernel reference Implementation
 * (C) Copyright IBM Corp. 2001, 2004
 * Copyright (c) 1999-2000 Cisco, Inc.
 * Copyright (c) 1999-2001 Motorola, Inc.
 * Copyright (c) 2001 Intel Corp.
 * Copyright (c) 2001 Nokia, Inc.
 * Copyright (c) 2001 La Monte H.P. Yarroll
 *
 * This file is part of the SCTP kernel reference Implementation
 *
 * Various protocol defined structures.
 *
 * The SCTP reference implementation is free software;
 * you can redistribute it and/or modify it under the terms of
 * the GNU General Public License as published by
 * the Free Software Foundation; either version 2, or (at your option)
 * any later version.
 *
 * The SCTP reference implementation is distributed in the hope that it
 * will be useful, but WITHOUT ANY WARRANTY; without even the implied
 *                 ************************
 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 * See the GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with GNU CC; see the file COPYING.  If not, write to
 * the Free Software Foundation, 59 Temple Place - Suite 330,
 * Boston, MA 02111-1307, USA.
 *
 * Please send any bug reports or fixes you make to the
 * email address(es):
 *    lksctp developers <lksctp-developerst@lists.sourceforge.net>
 *
 * Or submit a bug report through the following website:
 *    http://www.sf.net/projects/lksctp
 *
 * Written or modified by:
 *    La Monte H.P. Yarroll <piggy@acm.org>
 *    Karl Knutson <karl@athena.chicago.il.us>
 *    Jon Grimm <jgrimm@us.ibm.com>
 *    Xingang Guo <xingang.guo@intel.com>
 *    randall@sctp.chicago.il.us
 *    kmorneau@cisco.com
 *    qxie1@email.mot.com
 *    Sridhar Samudrala <sri@us.ibm.com>
 *    Kevin Gao <kevin.gao@intel.com>
 *
 * Any bugs reported given to us we will try to fix... any fixes shared will
 * be incorporated into the next SCTP release.
 */
#ifndef __LINUX_SCTP_H__
#define __LINUX_SCTP_H__

#include <linux/in.h>		/* We need in_addr.  */
#include <linux/in6.h>		/* We need in6_addr.  */


/* Section 3.1.  SCTP Common Header Format */
typedef struct sctphdr {
	__be16 source;
	__be16 dest;
	__be32 vtag;
	__be32 checksum;
} __attribute__((packed)) sctp_sctphdr_t;

#ifdef __KERNEL__
#include <linux/skbuff.h>

static inline struct sctphdr *sctp_hdr(const struct sk_buff *skb)
{
	return (struct sctphdr *)skb_transport_header(skb);
}
#endif

/* Section 3.2.  Chunk Field Descriptions. */
typedef struct sctp_chunkhdr {
	__u8 type;
	__u8 flags;
	__be16 length;
} __attribute__((packed)) sctp_chunkhdr_t;


/* Section 3.2.  Chunk Type Values.
 * [Chunk Type] identifies the type of information contained in the Chunk
 * Value field. It takes a value from 0 to 254. The value of 255 is
 * reserved for future use as an extension field.
 */
typedef enum {
	SCTP_CID_DATA			= 0,
        SCTP_CID_INIT			= 1,
        SCTP_CID_INIT_ACK		= 2,
        SCTP_CID_SACK			= 3,
        SCTP_CID_HEARTBEAT		= 4,
        SCTP_CID_HEARTBEAT_ACK		= 5,
        SCTP_CID_ABORT			= 6,
        SCTP_CID_SHUTDOWN		= 7,
        SCTP_CID_SHUTDOWN_ACK		= 8,
        SCTP_CID_ERROR			= 9,
        SCTP_CID_COOKIE_ECHO		= 10,
        SCTP_CID_COOKIE_ACK	        = 11,
        SCTP_CID_ECN_ECNE		= 12,
        SCTP_CID_ECN_CWR		= 13,
        SCTP_CID_SHUTDOWN_COMPLETE	= 14,

	/* PR-SCTP Sec 3.2 */
	SCTP_CID_FWD_TSN		= 0xC0,

	/* Use hex, as defined in ADDIP sec. 3.1 */
	SCTP_CID_ASCONF			= 0xC1,
	SCTP_CID_ASCONF_ACK		= 0x80,
} sctp_cid_t; /* enum */


/* Section 3.2
 *  Chunk Types are encoded such that the highest-order two bits specify
 *  the action that must be taken if the processing endpoint does not
 *  recognize the Chunk Type.
 */
typedef enum {
	SCTP_CID_ACTION_DISCARD     = 0x00,
	SCTP_CID_ACTION_DISCARD_ERR = 0x40,
	SCTP_CID_ACTION_SKIP        = 0x80,
	SCTP_CID_ACTION_SKIP_ERR    = 0xc0,
} sctp_cid_action_t;

enum { SCTP_CID_ACTION_MASK = 0xc0, };

/* This flag is used in Chunk Flags for ABORT and SHUTDOWN COMPLETE.
 *
 * 3.3.7 Abort Association (ABORT) (6):
 *    The T bit is set to 0 if the sender had a TCB that it destroyed.
 *    If the sender did not have a TCB it should set this bit to 1.
 */
enum { SCTP_CHUNK_FLAG_T = 0x01 };

/*
 *  Set the T bit
 *
 *      0                   1                   2                   3
 *      0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
 *     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *     |   Type = 14   |Reserved     |T|      Length = 4               |
 *     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *
 * Chunk Flags: 8 bits
 *
 *   Reserved:  7 bits
 *     Set to 0 on transmit and ignored on receipt.
 *
 *   T bit:  1 bit
 *     The T bit is set to 0 if the sender had a TCB that it destroyed. If
 *     the sender did NOT have a TCB it should set this bit to 1.
 *
 * Note: Special rules apply to this chunk for verification, please
 * see Section 8.5.1 for details.
 */

#define sctp_test_T_bit(c)    ((c)->chunk_hdr->flags & SCTP_CHUNK_FLAG_T)

/* RFC 2960
 * Section 3.2.1 Optional/Variable-length Parmaeter Format.
 */

typedef struct sctp_paramhdr {
	__be16 type;
	__be16 length;
} __attribute__((packed)) sctp_paramhdr_t;

typedef enum {

	/* RFC 2960 Section 3.3.5 */
	SCTP_PARAM_HEARTBEAT_INFO		= __constant_htons(1),
	/* RFC 2960 Section 3.3.2.1 */
	SCTP_PARAM_IPV4_ADDRESS			= __constant_htons(5),
	SCTP_PARAM_IPV6_ADDRESS			= __constant_htons(6),
	SCTP_PARAM_STATE_COOKIE			= __constant_htons(7),
	SCTP_PARAM_UNRECOGNIZED_PARAMETERS	= __constant_htons(8),
	SCTP_PARAM_COOKIE_PRESERVATIVE		= __constant_htons(9),
	SCTP_PARAM_HOST_NAME_ADDRESS		= __constant_htons(11),
	SCTP_PARAM_SUPPORTED_ADDRESS_TYPES	= __constant_htons(12),
	SCTP_PARAM_ECN_CAPABLE			= __constant_htons(0x8000),

	/* Add-IP: Supported Extensions, Section 4.2 */
	SCTP_PARAM_SUPPORTED_EXT	= __constant_htons(0x8008),

	/* PR-SCTP Sec 3.1 */
	SCTP_PARAM_FWD_TSN_SUPPORT	= __constant_htons(0xc000),

	/* Add-IP Extension. Section 3.2 */
	SCTP_PARAM_ADD_IP		= __constant_htons(0xc001),
	SCTP_PARAM_DEL_IP		= __constant_htons(0xc002),
	SCTP_PARAM_ERR_CAUSE		= __constant_htons(0xc003),
	SCTP_PARAM_SET_PRIMARY		= __constant_htons(0xc004),
	SCTP_PARAM_SUCCESS_REPORT	= __constant_htons(0xc005),
	SCTP_PARAM_ADAPTATION_LAYER_IND = __constant_htons(0xc006),

} sctp_param_t; /* enum */


/* RFC 2960 Section 3.2.1
 *  The Parameter Types are encoded such that the highest-order two bits
 *  specify the action that must be taken if the processing endpoint does
 *  not recognize the Parameter Type.
 *
 */
typedef enum {
	SCTP_PARAM_ACTION_DISCARD     = __constant_htons(0x0000),
	SCTP_PARAM_ACTION_DISCARD_ERR = __constant_htons(0x4000),
	SCTP_PARAM_ACTION_SKIP        = __constant_htons(0x8000),
	SCTP_PARAM_ACTION_SKIP_ERR    = __constant_htons(0xc000),
} sctp_param_action_t;

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

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

typedef struct sctp_datahdr {
	__be32 tsn;
	__be16 stream;
	__be16 ssn;
	__be32 ppid;
	__u8  payload[0];
} __attribute__((packed)) sctp_datahdr_t;

typedef struct sctp_data_chunk {
        sctp_chunkhdr_t chunk_hdr;
        sctp_datahdr_t  data_hdr;
} __attribute__((packed)) sctp_data_chunk_t;

/* DATA Chuck Specific Flags */
enum {
	SCTP_DATA_MIDDLE_FRAG	= 0x00,
	SCTP_DATA_LAST_FRAG	= 0x01,
	SCTP_DATA_FIRST_FRAG	= 0x02,
	SCTP_DATA_NOT_FRAG	= 0x03,
	SCTP_DATA_UNORDERED	= 0x04,
};
enum { SCTP_DATA_FRAG_MASK = 0x03, };


/* RFC 2960 Section 3.3.2 Initiation (INIT) (1)
 *
 *  This chunk is used to initiate a SCTP association between two
 *  endpoints.
 */
typedef struct sctp_inithdr {
	__be32 init_tag;
	__be32 a_rwnd;
	__be16 num_outbound_streams;
	__be16 num_inbound_streams;
	__be32 initial_tsn;
	__u8  params[0];
} __attribute__((packed)) sctp_inithdr_t;

typedef struct sctp_init_chunk {
	sctp_chunkhdr_t chunk_hdr;
	sctp_inithdr_t init_hdr;
} __attribute__((packed)) sctp_init_chunk_t;


/* Section 3.3.2.1. IPv4 Address Parameter (5) */
typedef struct sctp_ipv4addr_param {
	sctp_paramhdr_t param_hdr;
	struct in_addr  addr;
} __attribute__((packed)) sctp_ipv4addr_param_t;

/* Section 3.3.2.1. IPv6 Address Parameter (6) */
typedef struct sctp_ipv6addr_param {
	sctp_paramhdr_t param_hdr;
	struct in6_addr addr;
} __attribute__((packed)) sctp_ipv6addr_param_t;

/* Section 3.3.2.1 Cookie Preservative (9) */
typedef struct sctp_cookie_preserve_param {
	sctp_paramhdr_t param_hdr;
	__be32          lifespan_increment;
} __attribute__((packed)) sctp_cookie_preserve_param_t;

/* Section 3.3.2.1 Host Name Address (11) */
typedef struct sctp_hostname_param {
	sctp_paramhdr_t param_hdr;
	uint8_t hostname[0];
} __attribute__((packed)) sctp_hostname_param_t;

/* Section 3.3.2.1 Supported Address Types (12) */
typedef struct sctp_supported_addrs_param {
	sctp_paramhdr_t param_hdr;
	__be16 types[0];
} __attribute__((packed)) sctp_supported_addrs_param_t;

/* Appendix A. ECN Capable (32768) */
typedef struct sctp_ecn_capable_param {
	sctp_paramhdr_t param_hdr;
} __attribute__((packed)) sctp_ecn_capable_param_t;

/* ADDIP Section 3.2.6 Adaptation Layer Indication */
typedef struct sctp_adaptation_ind_param {
	struct sctp_paramhdr param_hdr;
	__be32 adaptation_ind;
} __attribute__((packed)) sctp_adaptation_ind_param_t;

/* ADDIP Section 4.2.7 Supported Extensions Parameter */
typedef struct sctp_supported_ext_param {
	struct sctp_paramhdr param_hdr;
	__u8 chunks[0];
} __attribute__((packed)) sctp_supported_ext_param_t;

/* RFC 2960.  Section 3.3.3 Initiation Acknowledgement (INIT ACK) (2):
 *   The INIT ACK chunk is used to acknowledge the initiation of an SCTP
 *   association.
 */
typedef sctp_init_chunk_t sctp_initack_chunk_t;

/* Section 3.3.3.1 State Cookie (7) */
typedef struct sctp_cookie_param {
	sctp_paramhdr_t p;
	__u8 body[0];
} __attribute__((packed)) sctp_cookie_param_t;

/* Section 3.3.3.1 Unrecognized Parameters (8) */
typedef struct sctp_unrecognized_param {
	sctp_paramhdr_t param_hdr;
	sctp_paramhdr_t unrecognized;
} __attribute__((packed)) sctp_unrecognized_param_t;



/*
 * 3.3.4 Selective Acknowledgement (SACK) (3):
 *
 *  This chunk is sent to the peer endpoint to acknowledge received DATA
 *  chunks and to inform the peer endpoint of gaps in the received
 *  subsequences of DATA chunks as represented by their TSNs.
 */

typedef struct sctp_gap_ack_block {
	__be16 start;
	__be16 end;
} __attribute__((packed)) sctp_gap_ack_block_t;

typedef __be32 sctp_dup_tsn_t;

typedef union {
	sctp_gap_ack_block_t	gab;
        sctp_dup_tsn_t		dup;
} sctp_sack_variable_t;

typedef struct sctp_sackhdr {
	__be32 cum_tsn_ack;
	__be32 a_rwnd;
	__be16 num_gap_ack_blocks;
	__be16 num_dup_tsns;
	sctp_sack_variable_t variable[0];
} __attribute__((packed)) sctp_sackhdr_t;

typedef struct sctp_sack_chunk {
	sctp_chunkhdr_t chunk_hdr;
	sctp_sackhdr_t sack_hdr;
} __attribute__((packed)) sctp_sack_chunk_t;


/* RFC 2960.  Section 3.3.5 Heartbeat Request (HEARTBEAT) (4):
 *
 *  An endpoint should send this chunk to its peer endpoint to probe the
 *  reachability of a particular destination transport address defined in
 *  the present association.
 */

typedef struct sctp_heartbeathdr {
	sctp_paramhdr_t info;
} __attribute__((packed)) sctp_heartbeathdr_t;

typedef struct sctp_heartbeat_chunk {
	sctp_chunkhdr_t chunk_hdr;
	sctp_heartbeathdr_t hb_hdr;
} __attribute__((packed)) sctp_heartbeat_chunk_t;


/* For the abort and shutdown ACK we must carry the init tag in the
 * common header. Just the common header is all that is needed with a
 * chunk descriptor.
 */
typedef struct sctp_abort_chunk {
        sctp_chunkhdr_t uh;
} __attribute__((packed)) sctp_abort_chunk_t;


/* For the graceful shutdown we must carry the tag (in common header)
 * and the highest consecutive acking value.
 */
typedef struct sctp_shutdownhdr {
	__be32 cum_tsn_ack;
} __attribute__((packed)) sctp_shutdownhdr_t;

struct sctp_shutdown_chunk_t {
        sctp_chunkhdr_t    chunk_hdr;
        sctp_shutdownhdr_t shutdown_hdr;
} __attribute__ ((packed));

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

typedef struct sctp_errhdr {
	__be16 cause;
	__be16 length;
	__u8  variable[0];
} __attribute__((packed)) sctp_errhdr_t;

typedef struct sctp_operr_chunk {
        sctp_chunkhdr_t chunk_hdr;
	sctp_errhdr_t   err_hdr;
} __attribute__((packed)) sctp_operr_chunk_t;

/* RFC 2960 3.3.10 - Operation Error
 *
 * Cause Code: 16 bits (unsigned integer)
 *
 *     Defines the type of error conditions being reported.
 *    Cause Code
 *     Value           Cause Code
 *     ---------      ----------------
 *      1              Invalid Stream Identifier
 *      2              Missing Mandatory Parameter
 *      3              Stale Cookie Error
 *      4              Out of Resource
 *      5              Unresolvable Address
 *      6              Unrecognized Chunk Type
 *      7              Invalid Mandatory Parameter
 *      8              Unrecognized Parameters
 *      9              No User Data
 *     10              Cookie Received While Shutting Down
 */
typedef enum {

	SCTP_ERROR_NO_ERROR	   = __constant_htons(0x00),
	SCTP_ERROR_INV_STRM	   = __constant_htons(0x01),
	SCTP_ERROR_MISS_PARAM 	   = __constant_htons(0x02),
	SCTP_ERROR_STALE_COOKIE	   = __constant_htons(0x03),
	SCTP_ERROR_NO_RESOURCE 	   = __constant_htons(0x04),
	SCTP_ERROR_DNS_FAILED      = __constant_htons(0x05),
	SCTP_ERROR_UNKNOWN_CHUNK   = __constant_htons(0x06),
	SCTP_ERROR_INV_PARAM       = __constant_htons(0x07),
	SCTP_ERROR_UNKNOWN_PARAM   = __constant_htons(0x08),
	SCTP_ERROR_NO_DATA         = __constant_htons(0x09),
	SCTP_ERROR_COOKIE_IN_SHUTDOWN = __constant_htons(0x0a),


	/* SCTP Implementation Guide:
	 *  11  Restart of an association with new addresses
	 *  12  User Initiated Abort
	 *  13  Protocol Violation
	 */

	SCTP_ERROR_RESTART         = __constant_htons(0x0b),
	SCTP_ERROR_USER_ABORT      = __constant_htons(0x0c),
	SCTP_ERROR_PROTO_VIOLATION = __constant_htons(0x0d),

	/* ADDIP Section 3.3  New Error Causes
	 *
	 * Four new Error Causes are added to the SCTP Operational Errors,
	 * primarily for use in the ASCONF-ACK chunk.
	 *
	 * Value          Cause Code
	 * ---------      ----------------
	 * 0x0100          Request to Delete Last Remaining IP Address.
	 * 0x0101          Operation Refused Due to Resource Shortage.
	 * 0x0102          Request to Delete Source IP Address.
	 * 0x0103          Association Aborted due to illegal ASCONF-ACK
	 * 0x0104          Request refused - no authorization.
	 */
	SCTP_ERROR_DEL_LAST_IP	= __constant_htons(0x0100),
	SCTP_ERROR_RSRC_LOW	= __constant_htons(0x0101),
	SCTP_ERROR_DEL_SRC_IP	= __constant_htons(0x0102),
	SCTP_ERROR_ASCONF_ACK   = __constant_htons(0x0103),
	SCTP_ERROR_REQ_REFUSED	= __constant_htons(0x0104)
} sctp_error_t;



/* RFC 2960.  Appendix A.  Explicit Congestion Notification.
 *   Explicit Congestion Notification Echo (ECNE) (12)
 */
typedef struct sctp_ecnehdr {
	__be32 lowest_tsn;
} sctp_ecnehdr_t;

typedef struct sctp_ecne_chunk {
	sctp_chunkhdr_t chunk_hdr;
	sctp_ecnehdr_t ence_hdr;
} __attribute__((packed)) sctp_ecne_chunk_t;

/* RFC 2960.  Appendix A.  Explicit Congestion Notification.
 *   Congestion Window Reduced (CWR) (13)
 */
typedef struct sctp_cwrhdr {
	__be32 lowest_tsn;
} sctp_cwrhdr_t;

typedef struct sctp_cwr_chunk {
	sctp_chunkhdr_t chunk_hdr;
	sctp_cwrhdr_t cwr_hdr;
} __attribute__((packed)) sctp_cwr_chunk_t;

/* PR-SCTP
 * 3.2 Forward Cumulative TSN Chunk Definition (FORWARD TSN)
 *
 * Forward Cumulative TSN chunk has the following format:
 *
 *        0                   1                   2                   3
 *        0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
 *      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *      |   Type = 192  |  Flags = 0x00 |        Length = Variable      |
 *      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *      |                      New Cumulative TSN                       |
 *      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *      |         Stream-1              |       Stream Sequence-1       |
 *      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *      \                                                               /
 *      /                                                               \
 *      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *      |         Stream-N              |       Stream Sequence-N       |
 *      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *
 *      Chunk Flags:
 *
 *        Set to all zeros on transmit and ignored on receipt.
 *
 *      New Cumulative TSN: 32 bit u_int
 *
 *       This indicates the new cumulative TSN to the data receiver. Upon
 *       the reception of this value, the data receiver MUST consider
 *       any missing TSNs earlier than or equal to this value as received
 *       and stop reporting them as gaps in any subsequent SACKs.
 *
 *      Stream-N: 16 bit u_int
 *
 *       This field holds a stream number that was skipped by this
 *       FWD-TSN.
 *
 *      Stream Sequence-N: 16 bit u_int
 *       This field holds the sequence number associated with the stream
 *       that was skipped. The stream sequence field holds the largest stream
 *       sequence number in this stream being skipped.  The receiver of
 *       the FWD-TSN's can use the Stream-N and Stream Sequence-N fields
 *       to enable delivery of any stranded TSN's that remain on the stream
 *       re-ordering queues. This field MUST NOT report TSN's corresponding
 *       to DATA chunk that are marked as unordered. For ordered DATA
 *       chunks this field MUST be filled in.
 */
struct sctp_fwdtsn_skip {
	__be16 stream;
	__be16 ssn;
} __attribute__((packed));

struct sctp_fwdtsn_hdr {
	__be32 new_cum_tsn;
	struct sctp_fwdtsn_skip skip[0];
} __attribute((packed));

struct sctp_fwdtsn_chunk {
	struct sctp_chunkhdr chunk_hdr;
	struct sctp_fwdtsn_hdr fwdtsn_hdr;
} __attribute((packed));


/* ADDIP
 * Section 3.1.1 Address Configuration Change Chunk (ASCONF)
 *
 * 	Serial Number: 32 bits (unsigned integer)
 *	This value represents a Serial Number for the ASCONF Chunk. The
 *	valid range of Serial Number is from 0 to 2^32-1.
 *	Serial Numbers wrap back to 0 after reaching 2^32 -1.
 *
 *	Address Parameter: 8 or 20 bytes (depending on type)
 *	The address is an address of the sender of the ASCONF chunk,
 *	the address MUST be considered part of the association by the
 *	peer endpoint. This field may be used by the receiver of the 
 *	ASCONF to help in finding the association. This parameter MUST
 *	be present in every ASCONF message i.e. it is a mandatory TLV
 *	parameter.
 *
 *	ASCONF Parameter: TLV format
 *	Each Address configuration change is represented by a TLV
 *	parameter as defined in Section 3.2. One or more requests may
 *	be present in an ASCONF Chunk.
 *
 * Section 3.1.2 Address Configuration Acknowledgement Chunk (ASCONF-ACK)
 * 
 *	Serial Number: 32 bits (unsigned integer)
 *	This value represents the Serial Number for the received ASCONF
 *	Chunk that is acknowledged by this chunk. This value is copied
 *	from the received ASCONF Chunk. 
 *
 *	ASCONF Parameter Response: TLV format
 *	The ASCONF Parameter Response is used in the ASCONF-ACK to
 *	report status of ASCONF processing.
 */
typedef struct sctp_addip_param {
	sctp_paramhdr_t	param_hdr;
	__be32		crr_id;
} __attribute__((packed)) sctp_addip_param_t;

typedef struct sctp_addiphdr {
	__be32	serial;
	__u8	params[0];
} __attribute__((packed)) sctp_addiphdr_t;

typedef struct sctp_addip_chunk {
	sctp_chunkhdr_t chunk_hdr;
	sctp_addiphdr_t addip_hdr;
} __attribute__((packed)) sctp_addip_chunk_t;

#endif /* __LINUX_SCTP_H__ */