xref: /linux/include/linux/sctp.h (revision 1a9239bb4253f9076b5b4b2a1a4e8d7defd77a95)
1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /* SCTP kernel reference Implementation
3  * (C) Copyright IBM Corp. 2001, 2004
4  * Copyright (c) 1999-2000 Cisco, Inc.
5  * Copyright (c) 1999-2001 Motorola, Inc.
6  * Copyright (c) 2001 Intel Corp.
7  * Copyright (c) 2001 Nokia, Inc.
8  * Copyright (c) 2001 La Monte H.P. Yarroll
9  *
10  * This file is part of the SCTP kernel reference Implementation
11  *
12  * Various protocol defined structures.
13  *
14  * Please send any bug reports or fixes you make to the
15  * email address(es):
16  *    lksctp developers <linux-sctp@vger.kernel.org>
17  *
18  * Or submit a bug report through the following website:
19  *    http://www.sf.net/projects/lksctp
20  *
21  * Written or modified by:
22  *    La Monte H.P. Yarroll <piggy@acm.org>
23  *    Karl Knutson <karl@athena.chicago.il.us>
24  *    Jon Grimm <jgrimm@us.ibm.com>
25  *    Xingang Guo <xingang.guo@intel.com>
26  *    randall@sctp.chicago.il.us
27  *    kmorneau@cisco.com
28  *    qxie1@email.mot.com
29  *    Sridhar Samudrala <sri@us.ibm.com>
30  *    Kevin Gao <kevin.gao@intel.com>
31  *
32  * Any bugs reported given to us we will try to fix... any fixes shared will
33  * be incorporated into the next SCTP release.
34  */
35 #ifndef __LINUX_SCTP_H__
36 #define __LINUX_SCTP_H__
37 
38 #include <linux/in.h>		/* We need in_addr.  */
39 #include <linux/in6.h>		/* We need in6_addr.  */
40 #include <linux/skbuff.h>
41 
42 #include <uapi/linux/sctp.h>
43 
44 /* Section 3.1.  SCTP Common Header Format */
45 struct sctphdr {
46 	__be16 source;
47 	__be16 dest;
48 	__be32 vtag;
49 	__le32 checksum;
50 };
51 
sctp_hdr(const struct sk_buff * skb)52 static inline struct sctphdr *sctp_hdr(const struct sk_buff *skb)
53 {
54 	return (struct sctphdr *)skb_transport_header(skb);
55 }
56 
57 /* Section 3.2.  Chunk Field Descriptions. */
58 struct sctp_chunkhdr {
59 	__u8 type;
60 	__u8 flags;
61 	__be16 length;
62 };
63 
64 
65 /* Section 3.2.  Chunk Type Values.
66  * [Chunk Type] identifies the type of information contained in the Chunk
67  * Value field. It takes a value from 0 to 254. The value of 255 is
68  * reserved for future use as an extension field.
69  */
70 enum sctp_cid {
71 	SCTP_CID_DATA			= 0,
72         SCTP_CID_INIT			= 1,
73         SCTP_CID_INIT_ACK		= 2,
74         SCTP_CID_SACK			= 3,
75         SCTP_CID_HEARTBEAT		= 4,
76         SCTP_CID_HEARTBEAT_ACK		= 5,
77         SCTP_CID_ABORT			= 6,
78         SCTP_CID_SHUTDOWN		= 7,
79         SCTP_CID_SHUTDOWN_ACK		= 8,
80         SCTP_CID_ERROR			= 9,
81         SCTP_CID_COOKIE_ECHO		= 10,
82         SCTP_CID_COOKIE_ACK	        = 11,
83         SCTP_CID_ECN_ECNE		= 12,
84         SCTP_CID_ECN_CWR		= 13,
85         SCTP_CID_SHUTDOWN_COMPLETE	= 14,
86 
87 	/* AUTH Extension Section 4.1 */
88 	SCTP_CID_AUTH			= 0x0F,
89 
90 	/* sctp ndata 5.1. I-DATA */
91 	SCTP_CID_I_DATA			= 0x40,
92 
93 	/* PR-SCTP Sec 3.2 */
94 	SCTP_CID_FWD_TSN		= 0xC0,
95 
96 	/* Use hex, as defined in ADDIP sec. 3.1 */
97 	SCTP_CID_ASCONF			= 0xC1,
98 	SCTP_CID_I_FWD_TSN		= 0xC2,
99 	SCTP_CID_ASCONF_ACK		= 0x80,
100 	SCTP_CID_RECONF			= 0x82,
101 	SCTP_CID_PAD			= 0x84,
102 }; /* enum */
103 
104 
105 /* Section 3.2
106  *  Chunk Types are encoded such that the highest-order two bits specify
107  *  the action that must be taken if the processing endpoint does not
108  *  recognize the Chunk Type.
109  */
110 enum {
111 	SCTP_CID_ACTION_DISCARD     = 0x00,
112 	SCTP_CID_ACTION_DISCARD_ERR = 0x40,
113 	SCTP_CID_ACTION_SKIP        = 0x80,
114 	SCTP_CID_ACTION_SKIP_ERR    = 0xc0,
115 };
116 
117 enum { SCTP_CID_ACTION_MASK = 0xc0, };
118 
119 /* This flag is used in Chunk Flags for ABORT and SHUTDOWN COMPLETE.
120  *
121  * 3.3.7 Abort Association (ABORT) (6):
122  *    The T bit is set to 0 if the sender had a TCB that it destroyed.
123  *    If the sender did not have a TCB it should set this bit to 1.
124  */
125 enum { SCTP_CHUNK_FLAG_T = 0x01 };
126 
127 /*
128  *  Set the T bit
129  *
130  *      0                   1                   2                   3
131  *      0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
132  *     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
133  *     |   Type = 14   |Reserved     |T|      Length = 4               |
134  *     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
135  *
136  * Chunk Flags: 8 bits
137  *
138  *   Reserved:  7 bits
139  *     Set to 0 on transmit and ignored on receipt.
140  *
141  *   T bit:  1 bit
142  *     The T bit is set to 0 if the sender had a TCB that it destroyed. If
143  *     the sender did NOT have a TCB it should set this bit to 1.
144  *
145  * Note: Special rules apply to this chunk for verification, please
146  * see Section 8.5.1 for details.
147  */
148 
149 #define sctp_test_T_bit(c)    ((c)->chunk_hdr->flags & SCTP_CHUNK_FLAG_T)
150 
151 /* RFC 2960
152  * Section 3.2.1 Optional/Variable-length Parmaeter Format.
153  */
154 
155 struct sctp_paramhdr {
156 	__be16 type;
157 	__be16 length;
158 };
159 
160 enum sctp_param {
161 
162 	/* RFC 2960 Section 3.3.5 */
163 	SCTP_PARAM_HEARTBEAT_INFO		= cpu_to_be16(1),
164 	/* RFC 2960 Section 3.3.2.1 */
165 	SCTP_PARAM_IPV4_ADDRESS			= cpu_to_be16(5),
166 	SCTP_PARAM_IPV6_ADDRESS			= cpu_to_be16(6),
167 	SCTP_PARAM_STATE_COOKIE			= cpu_to_be16(7),
168 	SCTP_PARAM_UNRECOGNIZED_PARAMETERS	= cpu_to_be16(8),
169 	SCTP_PARAM_COOKIE_PRESERVATIVE		= cpu_to_be16(9),
170 	SCTP_PARAM_HOST_NAME_ADDRESS		= cpu_to_be16(11),
171 	SCTP_PARAM_SUPPORTED_ADDRESS_TYPES	= cpu_to_be16(12),
172 	SCTP_PARAM_ECN_CAPABLE			= cpu_to_be16(0x8000),
173 
174 	/* AUTH Extension Section 3 */
175 	SCTP_PARAM_RANDOM			= cpu_to_be16(0x8002),
176 	SCTP_PARAM_CHUNKS			= cpu_to_be16(0x8003),
177 	SCTP_PARAM_HMAC_ALGO			= cpu_to_be16(0x8004),
178 
179 	/* Add-IP: Supported Extensions, Section 4.2 */
180 	SCTP_PARAM_SUPPORTED_EXT	= cpu_to_be16(0x8008),
181 
182 	/* PR-SCTP Sec 3.1 */
183 	SCTP_PARAM_FWD_TSN_SUPPORT	= cpu_to_be16(0xc000),
184 
185 	/* Add-IP Extension. Section 3.2 */
186 	SCTP_PARAM_ADD_IP		= cpu_to_be16(0xc001),
187 	SCTP_PARAM_DEL_IP		= cpu_to_be16(0xc002),
188 	SCTP_PARAM_ERR_CAUSE		= cpu_to_be16(0xc003),
189 	SCTP_PARAM_SET_PRIMARY		= cpu_to_be16(0xc004),
190 	SCTP_PARAM_SUCCESS_REPORT	= cpu_to_be16(0xc005),
191 	SCTP_PARAM_ADAPTATION_LAYER_IND = cpu_to_be16(0xc006),
192 
193 	/* RE-CONFIG. Section 4 */
194 	SCTP_PARAM_RESET_OUT_REQUEST		= cpu_to_be16(0x000d),
195 	SCTP_PARAM_RESET_IN_REQUEST		= cpu_to_be16(0x000e),
196 	SCTP_PARAM_RESET_TSN_REQUEST		= cpu_to_be16(0x000f),
197 	SCTP_PARAM_RESET_RESPONSE		= cpu_to_be16(0x0010),
198 	SCTP_PARAM_RESET_ADD_OUT_STREAMS	= cpu_to_be16(0x0011),
199 	SCTP_PARAM_RESET_ADD_IN_STREAMS		= cpu_to_be16(0x0012),
200 }; /* enum */
201 
202 
203 /* RFC 2960 Section 3.2.1
204  *  The Parameter Types are encoded such that the highest-order two bits
205  *  specify the action that must be taken if the processing endpoint does
206  *  not recognize the Parameter Type.
207  *
208  */
209 enum {
210 	SCTP_PARAM_ACTION_DISCARD     = cpu_to_be16(0x0000),
211 	SCTP_PARAM_ACTION_DISCARD_ERR = cpu_to_be16(0x4000),
212 	SCTP_PARAM_ACTION_SKIP        = cpu_to_be16(0x8000),
213 	SCTP_PARAM_ACTION_SKIP_ERR    = cpu_to_be16(0xc000),
214 };
215 
216 enum { SCTP_PARAM_ACTION_MASK = cpu_to_be16(0xc000), };
217 
218 /* RFC 2960 Section 3.3.1 Payload Data (DATA) (0) */
219 
220 struct sctp_datahdr {
221 	__be32 tsn;
222 	__be16 stream;
223 	__be16 ssn;
224 	__u32 ppid;
225 };
226 
227 struct sctp_data_chunk {
228 	struct sctp_chunkhdr chunk_hdr;
229 	struct sctp_datahdr data_hdr;
230 };
231 
232 struct sctp_idatahdr {
233 	__be32 tsn;
234 	__be16 stream;
235 	__be16 reserved;
236 	__be32 mid;
237 	union {
238 		__u32 ppid;
239 		__be32 fsn;
240 	};
241 };
242 
243 struct sctp_idata_chunk {
244 	struct sctp_chunkhdr chunk_hdr;
245 	struct sctp_idatahdr data_hdr;
246 };
247 
248 /* DATA Chuck Specific Flags */
249 enum {
250 	SCTP_DATA_MIDDLE_FRAG	= 0x00,
251 	SCTP_DATA_LAST_FRAG	= 0x01,
252 	SCTP_DATA_FIRST_FRAG	= 0x02,
253 	SCTP_DATA_NOT_FRAG	= 0x03,
254 	SCTP_DATA_UNORDERED	= 0x04,
255 	SCTP_DATA_SACK_IMM	= 0x08,
256 };
257 enum { SCTP_DATA_FRAG_MASK = 0x03, };
258 
259 
260 /* RFC 2960 Section 3.3.2 Initiation (INIT) (1)
261  *
262  *  This chunk is used to initiate a SCTP association between two
263  *  endpoints.
264  */
265 struct sctp_inithdr {
266 	__be32 init_tag;
267 	__be32 a_rwnd;
268 	__be16 num_outbound_streams;
269 	__be16 num_inbound_streams;
270 	__be32 initial_tsn;
271 	/* __u8  params[]; */
272 };
273 
274 struct sctp_init_chunk {
275 	struct sctp_chunkhdr chunk_hdr;
276 	struct sctp_inithdr init_hdr;
277 };
278 
279 
280 /* Section 3.3.2.1. IPv4 Address Parameter (5) */
281 struct sctp_ipv4addr_param {
282 	struct sctp_paramhdr param_hdr;
283 	struct in_addr addr;
284 };
285 
286 /* Section 3.3.2.1. IPv6 Address Parameter (6) */
287 struct sctp_ipv6addr_param {
288 	struct sctp_paramhdr param_hdr;
289 	struct in6_addr addr;
290 };
291 
292 /* Section 3.3.2.1 Cookie Preservative (9) */
293 struct sctp_cookie_preserve_param {
294 	struct sctp_paramhdr param_hdr;
295 	__be32 lifespan_increment;
296 };
297 
298 /* Section 3.3.2.1 Host Name Address (11) */
299 struct sctp_hostname_param {
300 	struct sctp_paramhdr param_hdr;
301 	uint8_t hostname[];
302 };
303 
304 /* Section 3.3.2.1 Supported Address Types (12) */
305 struct sctp_supported_addrs_param {
306 	struct sctp_paramhdr param_hdr;
307 	__be16 types[];
308 };
309 
310 /* ADDIP Section 3.2.6 Adaptation Layer Indication */
311 struct sctp_adaptation_ind_param {
312 	struct sctp_paramhdr param_hdr;
313 	__be32 adaptation_ind;
314 };
315 
316 /* ADDIP Section 4.2.7 Supported Extensions Parameter */
317 struct sctp_supported_ext_param {
318 	struct sctp_paramhdr param_hdr;
319 	__u8 chunks[];
320 };
321 
322 /* AUTH Section 3.1 Random */
323 struct sctp_random_param {
324 	struct sctp_paramhdr param_hdr;
325 	__u8 random_val[];
326 };
327 
328 /* AUTH Section 3.2 Chunk List */
329 struct sctp_chunks_param {
330 	struct sctp_paramhdr param_hdr;
331 	__u8 chunks[];
332 };
333 
334 /* AUTH Section 3.3 HMAC Algorithm */
335 struct sctp_hmac_algo_param {
336 	struct sctp_paramhdr param_hdr;
337 	__be16 hmac_ids[];
338 };
339 
340 /* RFC 2960.  Section 3.3.3 Initiation Acknowledgement (INIT ACK) (2):
341  *   The INIT ACK chunk is used to acknowledge the initiation of an SCTP
342  *   association.
343  */
344 struct sctp_initack_chunk {
345 	struct sctp_chunkhdr chunk_hdr;
346 	struct sctp_inithdr init_hdr;
347 };
348 
349 /* Section 3.3.3.1 State Cookie (7) */
350 struct sctp_cookie_param {
351 	struct sctp_paramhdr p;
352 	__u8 body[];
353 };
354 
355 /* Section 3.3.3.1 Unrecognized Parameters (8) */
356 struct sctp_unrecognized_param {
357 	struct sctp_paramhdr param_hdr;
358 	struct sctp_paramhdr unrecognized;
359 };
360 
361 
362 
363 /*
364  * 3.3.4 Selective Acknowledgement (SACK) (3):
365  *
366  *  This chunk is sent to the peer endpoint to acknowledge received DATA
367  *  chunks and to inform the peer endpoint of gaps in the received
368  *  subsequences of DATA chunks as represented by their TSNs.
369  */
370 
371 struct sctp_gap_ack_block {
372 	__be16 start;
373 	__be16 end;
374 };
375 
376 union sctp_sack_variable {
377 	struct sctp_gap_ack_block gab;
378 	__be32 dup;
379 };
380 
381 struct sctp_sackhdr {
382 	__be32 cum_tsn_ack;
383 	__be32 a_rwnd;
384 	__be16 num_gap_ack_blocks;
385 	__be16 num_dup_tsns;
386 	/* union sctp_sack_variable variable[]; */
387 };
388 
389 struct sctp_sack_chunk {
390 	struct sctp_chunkhdr chunk_hdr;
391 	struct sctp_sackhdr sack_hdr;
392 };
393 
394 
395 /* RFC 2960.  Section 3.3.5 Heartbeat Request (HEARTBEAT) (4):
396  *
397  *  An endpoint should send this chunk to its peer endpoint to probe the
398  *  reachability of a particular destination transport address defined in
399  *  the present association.
400  */
401 
402 struct sctp_heartbeathdr {
403 	struct sctp_paramhdr info;
404 };
405 
406 struct sctp_heartbeat_chunk {
407 	struct sctp_chunkhdr chunk_hdr;
408 	struct sctp_heartbeathdr hb_hdr;
409 };
410 
411 
412 /* PAD chunk could be bundled with heartbeat chunk to probe pmtu */
413 struct sctp_pad_chunk {
414 	struct sctp_chunkhdr uh;
415 };
416 
417 
418 /* For the abort and shutdown ACK we must carry the init tag in the
419  * common header. Just the common header is all that is needed with a
420  * chunk descriptor.
421  */
422 struct sctp_abort_chunk {
423 	struct sctp_chunkhdr uh;
424 };
425 
426 
427 /* For the graceful shutdown we must carry the tag (in common header)
428  * and the highest consecutive acking value.
429  */
430 struct sctp_shutdownhdr {
431 	__be32 cum_tsn_ack;
432 };
433 
434 struct sctp_shutdown_chunk {
435 	struct sctp_chunkhdr chunk_hdr;
436 	struct sctp_shutdownhdr shutdown_hdr;
437 };
438 
439 /* RFC 2960.  Section 3.3.10 Operation Error (ERROR) (9) */
440 
441 struct sctp_errhdr {
442 	__be16 cause;
443 	__be16 length;
444 	/* __u8  variable[]; */
445 };
446 
447 struct sctp_operr_chunk {
448 	struct sctp_chunkhdr chunk_hdr;
449 	struct sctp_errhdr err_hdr;
450 };
451 
452 /* RFC 2960 3.3.10 - Operation Error
453  *
454  * Cause Code: 16 bits (unsigned integer)
455  *
456  *     Defines the type of error conditions being reported.
457  *    Cause Code
458  *     Value           Cause Code
459  *     ---------      ----------------
460  *      1              Invalid Stream Identifier
461  *      2              Missing Mandatory Parameter
462  *      3              Stale Cookie Error
463  *      4              Out of Resource
464  *      5              Unresolvable Address
465  *      6              Unrecognized Chunk Type
466  *      7              Invalid Mandatory Parameter
467  *      8              Unrecognized Parameters
468  *      9              No User Data
469  *     10              Cookie Received While Shutting Down
470  */
471 enum sctp_error {
472 
473 	SCTP_ERROR_NO_ERROR	   = cpu_to_be16(0x00),
474 	SCTP_ERROR_INV_STRM	   = cpu_to_be16(0x01),
475 	SCTP_ERROR_MISS_PARAM 	   = cpu_to_be16(0x02),
476 	SCTP_ERROR_STALE_COOKIE	   = cpu_to_be16(0x03),
477 	SCTP_ERROR_NO_RESOURCE 	   = cpu_to_be16(0x04),
478 	SCTP_ERROR_DNS_FAILED      = cpu_to_be16(0x05),
479 	SCTP_ERROR_UNKNOWN_CHUNK   = cpu_to_be16(0x06),
480 	SCTP_ERROR_INV_PARAM       = cpu_to_be16(0x07),
481 	SCTP_ERROR_UNKNOWN_PARAM   = cpu_to_be16(0x08),
482 	SCTP_ERROR_NO_DATA         = cpu_to_be16(0x09),
483 	SCTP_ERROR_COOKIE_IN_SHUTDOWN = cpu_to_be16(0x0a),
484 
485 
486 	/* SCTP Implementation Guide:
487 	 *  11  Restart of an association with new addresses
488 	 *  12  User Initiated Abort
489 	 *  13  Protocol Violation
490 	 *  14  Restart of an Association with New Encapsulation Port
491 	 */
492 
493 	SCTP_ERROR_RESTART         = cpu_to_be16(0x0b),
494 	SCTP_ERROR_USER_ABORT      = cpu_to_be16(0x0c),
495 	SCTP_ERROR_PROTO_VIOLATION = cpu_to_be16(0x0d),
496 	SCTP_ERROR_NEW_ENCAP_PORT  = cpu_to_be16(0x0e),
497 
498 	/* ADDIP Section 3.3  New Error Causes
499 	 *
500 	 * Four new Error Causes are added to the SCTP Operational Errors,
501 	 * primarily for use in the ASCONF-ACK chunk.
502 	 *
503 	 * Value          Cause Code
504 	 * ---------      ----------------
505 	 * 0x00A0          Request to Delete Last Remaining IP Address.
506 	 * 0x00A1          Operation Refused Due to Resource Shortage.
507 	 * 0x00A2          Request to Delete Source IP Address.
508 	 * 0x00A3          Association Aborted due to illegal ASCONF-ACK
509 	 * 0x00A4          Request refused - no authorization.
510 	 */
511 	SCTP_ERROR_DEL_LAST_IP	= cpu_to_be16(0x00A0),
512 	SCTP_ERROR_RSRC_LOW	= cpu_to_be16(0x00A1),
513 	SCTP_ERROR_DEL_SRC_IP	= cpu_to_be16(0x00A2),
514 	SCTP_ERROR_ASCONF_ACK   = cpu_to_be16(0x00A3),
515 	SCTP_ERROR_REQ_REFUSED	= cpu_to_be16(0x00A4),
516 
517 	/* AUTH Section 4.  New Error Cause
518 	 *
519 	 * This section defines a new error cause that will be sent if an AUTH
520 	 * chunk is received with an unsupported HMAC identifier.
521 	 * illustrates the new error cause.
522 	 *
523 	 * Cause Code      Error Cause Name
524 	 * --------------------------------------------------------------
525 	 * 0x0105          Unsupported HMAC Identifier
526 	 */
527 	 SCTP_ERROR_UNSUP_HMAC	= cpu_to_be16(0x0105)
528 };
529 
530 
531 
532 /* RFC 2960.  Appendix A.  Explicit Congestion Notification.
533  *   Explicit Congestion Notification Echo (ECNE) (12)
534  */
535 struct sctp_ecnehdr {
536 	__be32 lowest_tsn;
537 };
538 
539 struct sctp_ecne_chunk {
540 	struct sctp_chunkhdr chunk_hdr;
541 	struct sctp_ecnehdr ence_hdr;
542 };
543 
544 /* RFC 2960.  Appendix A.  Explicit Congestion Notification.
545  *   Congestion Window Reduced (CWR) (13)
546  */
547 struct sctp_cwrhdr {
548 	__be32 lowest_tsn;
549 };
550 
551 /* PR-SCTP
552  * 3.2 Forward Cumulative TSN Chunk Definition (FORWARD TSN)
553  *
554  * Forward Cumulative TSN chunk has the following format:
555  *
556  *        0                   1                   2                   3
557  *        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
558  *      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
559  *      |   Type = 192  |  Flags = 0x00 |        Length = Variable      |
560  *      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
561  *      |                      New Cumulative TSN                       |
562  *      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
563  *      |         Stream-1              |       Stream Sequence-1       |
564  *      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
565  *      \                                                               /
566  *      /                                                               \
567  *      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
568  *      |         Stream-N              |       Stream Sequence-N       |
569  *      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
570  *
571  *      Chunk Flags:
572  *
573  *        Set to all zeros on transmit and ignored on receipt.
574  *
575  *      New Cumulative TSN: 32 bit u_int
576  *
577  *       This indicates the new cumulative TSN to the data receiver. Upon
578  *       the reception of this value, the data receiver MUST consider
579  *       any missing TSNs earlier than or equal to this value as received
580  *       and stop reporting them as gaps in any subsequent SACKs.
581  *
582  *      Stream-N: 16 bit u_int
583  *
584  *       This field holds a stream number that was skipped by this
585  *       FWD-TSN.
586  *
587  *      Stream Sequence-N: 16 bit u_int
588  *       This field holds the sequence number associated with the stream
589  *       that was skipped. The stream sequence field holds the largest stream
590  *       sequence number in this stream being skipped.  The receiver of
591  *       the FWD-TSN's can use the Stream-N and Stream Sequence-N fields
592  *       to enable delivery of any stranded TSN's that remain on the stream
593  *       re-ordering queues. This field MUST NOT report TSN's corresponding
594  *       to DATA chunk that are marked as unordered. For ordered DATA
595  *       chunks this field MUST be filled in.
596  */
597 struct sctp_fwdtsn_skip {
598 	__be16 stream;
599 	__be16 ssn;
600 };
601 
602 struct sctp_fwdtsn_hdr {
603 	__be32 new_cum_tsn;
604 	/* struct sctp_fwdtsn_skip skip[]; */
605 };
606 
607 struct sctp_fwdtsn_chunk {
608 	struct sctp_chunkhdr chunk_hdr;
609 	struct sctp_fwdtsn_hdr fwdtsn_hdr;
610 };
611 
612 struct sctp_ifwdtsn_skip {
613 	__be16 stream;
614 	__u8 reserved;
615 	__u8 flags;
616 	__be32 mid;
617 };
618 
619 struct sctp_ifwdtsn_hdr {
620 	__be32 new_cum_tsn;
621 	/* struct sctp_ifwdtsn_skip skip[]; */
622 };
623 
624 struct sctp_ifwdtsn_chunk {
625 	struct sctp_chunkhdr chunk_hdr;
626 	struct sctp_ifwdtsn_hdr fwdtsn_hdr;
627 };
628 
629 /* ADDIP
630  * Section 3.1.1 Address Configuration Change Chunk (ASCONF)
631  *
632  * 	Serial Number: 32 bits (unsigned integer)
633  *	This value represents a Serial Number for the ASCONF Chunk. The
634  *	valid range of Serial Number is from 0 to 2^32-1.
635  *	Serial Numbers wrap back to 0 after reaching 2^32 -1.
636  *
637  *	Address Parameter: 8 or 20 bytes (depending on type)
638  *	The address is an address of the sender of the ASCONF chunk,
639  *	the address MUST be considered part of the association by the
640  *	peer endpoint. This field may be used by the receiver of the
641  *	ASCONF to help in finding the association. This parameter MUST
642  *	be present in every ASCONF message i.e. it is a mandatory TLV
643  *	parameter.
644  *
645  *	ASCONF Parameter: TLV format
646  *	Each Address configuration change is represented by a TLV
647  *	parameter as defined in Section 3.2. One or more requests may
648  *	be present in an ASCONF Chunk.
649  *
650  * Section 3.1.2 Address Configuration Acknowledgement Chunk (ASCONF-ACK)
651  *
652  *	Serial Number: 32 bits (unsigned integer)
653  *	This value represents the Serial Number for the received ASCONF
654  *	Chunk that is acknowledged by this chunk. This value is copied
655  *	from the received ASCONF Chunk.
656  *
657  *	ASCONF Parameter Response: TLV format
658  *	The ASCONF Parameter Response is used in the ASCONF-ACK to
659  *	report status of ASCONF processing.
660  */
661 struct sctp_addip_param {
662 	struct sctp_paramhdr param_hdr;
663 	__be32 crr_id;
664 };
665 
666 struct sctp_addiphdr {
667 	__be32	serial;
668 	/* __u8	params[]; */
669 };
670 
671 struct sctp_addip_chunk {
672 	struct sctp_chunkhdr chunk_hdr;
673 	struct sctp_addiphdr addip_hdr;
674 };
675 
676 /* AUTH
677  * Section 4.1  Authentication Chunk (AUTH)
678  *
679  *   This chunk is used to hold the result of the HMAC calculation.
680  *
681  *    0                   1                   2                   3
682  *    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
683  *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
684  *   | Type = 0x0F   |   Flags=0     |             Length            |
685  *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
686  *   |     Shared Key Identifier     |   HMAC Identifier             |
687  *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
688  *   |                                                               |
689  *   \                             HMAC                              /
690  *   /                                                               \
691  *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
692  *
693  *   Type: 1 byte (unsigned integer)
694  *   	This value MUST be set to 0x0F for  all AUTH-chunks.
695  *
696  *   Flags: 1 byte (unsigned integer)
697  *	Set to zero on transmit and ignored on receipt.
698  *
699  *   Length: 2 bytes (unsigned integer)
700  *   	This value holds the length of the HMAC in bytes plus 8.
701  *
702  *  Shared Key Identifier: 2 bytes (unsigned integer)
703  *	This value describes which endpoint pair shared key is used.
704  *
705  *   HMAC Identifier: 2 bytes (unsigned integer)
706  *   	This value describes which message digest is being used.  Table 2
707  *	shows the currently defined values.
708  *
709  *    The following Table 2 shows the currently defined values for HMAC
710  *       identifiers.
711  *
712  *	 +-----------------+--------------------------+
713  *	 | HMAC Identifier | Message Digest Algorithm |
714  *	 +-----------------+--------------------------+
715  *	 | 0               | Reserved                 |
716  *	 | 1               | SHA-1 defined in [8]     |
717  *	 | 2               | Reserved                 |
718  *	 | 3               | SHA-256 defined in [8]   |
719  *	 +-----------------+--------------------------+
720  *
721  *
722  *   HMAC: n bytes (unsigned integer) This hold the result of the HMAC
723  *      calculation.
724  */
725 struct sctp_authhdr {
726 	__be16 shkey_id;
727 	__be16 hmac_id;
728 	/* __u8   hmac[]; */
729 };
730 
731 struct sctp_auth_chunk {
732 	struct sctp_chunkhdr chunk_hdr;
733 	struct sctp_authhdr auth_hdr;
734 };
735 
736 struct sctp_infox {
737 	struct sctp_info *sctpinfo;
738 	struct sctp_association *asoc;
739 };
740 
741 struct sctp_reconf_chunk {
742 	struct sctp_chunkhdr chunk_hdr;
743 	/* __u8 params[]; */
744 };
745 
746 struct sctp_strreset_outreq {
747 	struct sctp_paramhdr param_hdr;
748 	__be32 request_seq;
749 	__be32 response_seq;
750 	__be32 send_reset_at_tsn;
751 	__be16 list_of_streams[];
752 };
753 
754 struct sctp_strreset_inreq {
755 	struct sctp_paramhdr param_hdr;
756 	__be32 request_seq;
757 	__be16 list_of_streams[];
758 };
759 
760 struct sctp_strreset_tsnreq {
761 	struct sctp_paramhdr param_hdr;
762 	__be32 request_seq;
763 };
764 
765 struct sctp_strreset_addstrm {
766 	struct sctp_paramhdr param_hdr;
767 	__be32 request_seq;
768 	__be16 number_of_streams;
769 	__be16 reserved;
770 };
771 
772 enum {
773 	SCTP_STRRESET_NOTHING_TO_DO	= 0x00,
774 	SCTP_STRRESET_PERFORMED		= 0x01,
775 	SCTP_STRRESET_DENIED		= 0x02,
776 	SCTP_STRRESET_ERR_WRONG_SSN	= 0x03,
777 	SCTP_STRRESET_ERR_IN_PROGRESS	= 0x04,
778 	SCTP_STRRESET_ERR_BAD_SEQNO	= 0x05,
779 	SCTP_STRRESET_IN_PROGRESS	= 0x06,
780 };
781 
782 struct sctp_strreset_resp {
783 	struct sctp_paramhdr param_hdr;
784 	__be32 response_seq;
785 	__be32 result;
786 };
787 
788 struct sctp_strreset_resptsn {
789 	struct sctp_paramhdr param_hdr;
790 	__be32 response_seq;
791 	__be32 result;
792 	__be32 senders_next_tsn;
793 	__be32 receivers_next_tsn;
794 };
795 
796 enum {
797 	SCTP_DSCP_SET_MASK = 0x1,
798 	SCTP_DSCP_VAL_MASK = 0xfc,
799 	SCTP_FLOWLABEL_SET_MASK = 0x100000,
800 	SCTP_FLOWLABEL_VAL_MASK = 0xfffff
801 };
802 
803 /* UDP Encapsulation
804  * draft-tuexen-tsvwg-sctp-udp-encaps-cons-03.html#section-4-4
805  *
806  *   The error cause indicating an "Restart of an Association with
807  *   New Encapsulation Port"
808  *
809  * 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
810  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
811  * |        Cause Code = 14        |       Cause Length = 8        |
812  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
813  * |   Current Encapsulation Port  |     New Encapsulation Port    |
814  * +-------------------------------+-------------------------------+
815  */
816 struct sctp_new_encap_port_hdr {
817 	__be16 cur_port;
818 	__be16 new_port;
819 };
820 
821 /* Round an int up to the next multiple of 4.  */
822 #define SCTP_PAD4(s) (((s)+3)&~3)
823 /* Truncate to the previous multiple of 4.  */
824 #define SCTP_TRUNC4(s) ((s)&~3)
825 
826 #endif /* __LINUX_SCTP_H__ */
827