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sctp: fix to calc the INIT/INIT-ACK chunk length correctly is set
[linux-2.6-block.git] / net / sctp / sm_make_chunk.c
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60c778b2 1/* SCTP kernel implementation
1da177e4
LT		 2 * (C) Copyright IBM Corp. 2001, 2004
3 * Copyright (c) 1999-2000 Cisco, Inc.
4 * Copyright (c) 1999-2001 Motorola, Inc.
5 * Copyright (c) 2001-2002 Intel Corp.
6 *
60c778b2 7 * This file is part of the SCTP kernel implementation
1da177e4
LT		 8 *
9 * These functions work with the state functions in sctp_sm_statefuns.c
10 * to implement the state operations. These functions implement the
11 * steps which require modifying existing data structures.
12 *
60c778b2 13 * This SCTP implementation is free software;
1da177e4
LT		 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 *
60c778b2 19 * This SCTP implementation is distributed in the hope that it
1da177e4
LT		 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-developers@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 * C. Robin <chris@hundredacre.ac.uk>
41 * Jon Grimm <jgrimm@us.ibm.com>
42 * Xingang Guo <xingang.guo@intel.com>
43 * Dajiang Zhang <dajiang.zhang@nokia.com>
44 * Sridhar Samudrala <sri@us.ibm.com>
45 * Daisy Chang <daisyc@us.ibm.com>
46 * Ardelle Fan <ardelle.fan@intel.com>
47 * Kevin Gao <kevin.gao@intel.com>
48 *
49 * Any bugs reported given to us we will try to fix... any fixes shared will
50 * be incorporated into the next SCTP release.
51 */
52
53#include <linux/types.h>
54#include <linux/kernel.h>
55#include <linux/ip.h>
56#include <linux/ipv6.h>
57#include <linux/net.h>
58#include <linux/inet.h>
ebc3bbcf 59#include <linux/scatterlist.h>
1da177e4 60#include <linux/crypto.h>
5a0e3ad6 61#include <linux/slab.h>
1da177e4
LT		 62#include <net/sock.h>
63
64#include <linux/skbuff.h>
65#include <linux/random.h> /* for get_random_bytes */
66#include <net/sctp/sctp.h>
67#include <net/sctp/sm.h>
68
1da177e4
LT		 69SCTP_STATIC
70struct sctp_chunk *sctp_make_chunk(const struct sctp_association *asoc,
71 __u8 type, __u8 flags, int paylen);
72static sctp_cookie_param_t *sctp_pack_cookie(const struct sctp_endpoint *ep,
73 const struct sctp_association *asoc,
74 const struct sctp_chunk *init_chunk,
75 int *cookie_len,
76 const __u8 *raw_addrs, int addrs_len);
77static int sctp_process_param(struct sctp_association *asoc,
78 union sctp_params param,
79 const union sctp_addr *peer_addr,
dd0fc66f 80 gfp_t gfp);
8ee4be37
VY		 81static void *sctp_addto_param(struct sctp_chunk *chunk, int len,
82 const void *data);
1da177e4
LT		 83
84/* What was the inbound interface for this chunk? */
85int sctp_chunk_iif(const struct sctp_chunk *chunk)
86{
87 struct sctp_af *af;
88 int iif = 0;
89
eddc9ec5 90 af = sctp_get_af_specific(ipver2af(ip_hdr(chunk->skb)->version));
1da177e4
LT		 91 if (af)
92 iif = af->skb_iif(chunk->skb);
93
94 return iif;
95}
96
97/* RFC 2960 3.3.2 Initiation (INIT) (1)
98 *
99 * Note 2: The ECN capable field is reserved for future use of
100 * Explicit Congestion Notification.
101 */
102static const struct sctp_paramhdr ecap_param = {
103 SCTP_PARAM_ECN_CAPABLE,
09640e63 104 cpu_to_be16(sizeof(struct sctp_paramhdr)),
1da177e4
LT		 105};
106static const struct sctp_paramhdr prsctp_param = {
107 SCTP_PARAM_FWD_TSN_SUPPORT,
09640e63 108 cpu_to_be16(sizeof(struct sctp_paramhdr)),
1da177e4
LT		 109};
110
111/* A helper to initialize to initialize an op error inside a
112 * provided chunk, as most cause codes will be embedded inside an
113 * abort chunk.
114 */
5bf2db03 115void sctp_init_cause(struct sctp_chunk *chunk, __be16 cause_code,
00f1c2df 116 size_t paylen)
1da177e4
LT		 117{
118 sctp_errhdr_t err;
1da177e4
LT		 119 __u16 len;
120
d808ad9a 121 /* Cause code constants are now defined in network order. */
1da177e4
LT		 122 err.cause = cause_code;
123 len = sizeof(sctp_errhdr_t) + paylen;
1da177e4 124 err.length = htons(len);
4a1c0107 125 chunk->subh.err_hdr = sctp_addto_chunk(chunk, sizeof(sctp_errhdr_t), &err);
1da177e4
LT		 126}
127
128/* 3.3.2 Initiation (INIT) (1)
129 *
130 * This chunk is used to initiate a SCTP association between two
131 * endpoints. The format of the INIT chunk is shown below:
132 *
133 * 0 1 2 3
134 * 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
135 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
136 * | Type = 1 | Chunk Flags | Chunk Length |
137 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
138 * | Initiate Tag |
139 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
140 * | Advertised Receiver Window Credit (a_rwnd) |
141 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
142 * | Number of Outbound Streams | Number of Inbound Streams |
143 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
144 * | Initial TSN |
145 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
146 * \ \
147 * / Optional/Variable-Length Parameters /
148 * \ \
149 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
150 *
151 *
152 * The INIT chunk contains the following parameters. Unless otherwise
153 * noted, each parameter MUST only be included once in the INIT chunk.
154 *
155 * Fixed Parameters Status
156 * ----------------------------------------------
157 * Initiate Tag Mandatory
158 * Advertised Receiver Window Credit Mandatory
159 * Number of Outbound Streams Mandatory
160 * Number of Inbound Streams Mandatory
161 * Initial TSN Mandatory
162 *
163 * Variable Parameters Status Type Value
164 * -------------------------------------------------------------
165 * IPv4 Address (Note 1) Optional 5
166 * IPv6 Address (Note 1) Optional 6
167 * Cookie Preservative Optional 9
168 * Reserved for ECN Capable (Note 2) Optional 32768 (0x8000)
169 * Host Name Address (Note 3) Optional 11
170 * Supported Address Types (Note 4) Optional 12
171 */
172struct sctp_chunk *sctp_make_init(const struct sctp_association *asoc,
173 const struct sctp_bind_addr *bp,
dd0fc66f 174 gfp_t gfp, int vparam_len)
1da177e4
LT		 175{
176 sctp_inithdr_t init;
177 union sctp_params addrs;
178 size_t chunksize;
179 struct sctp_chunk *retval = NULL;
180 int num_types, addrs_len = 0;
181 struct sctp_sock *sp;
182 sctp_supported_addrs_param_t sat;
3dbe8656 183 __be16 types[2];
0f3fffd8 184 sctp_adaptation_ind_param_t aiparam;
131a47e3
VY		 185 sctp_supported_ext_param_t ext_param;
186 int num_ext = 0;
187 __u8 extensions[3];
730fc3d0
VY		 188 sctp_paramhdr_t *auth_chunks = NULL,
189 *auth_hmacs = NULL;
1da177e4
LT		 190
191 /* RFC 2960 3.3.2 Initiation (INIT) (1)
192 *
193 * Note 1: The INIT chunks can contain multiple addresses that
194 * can be IPv4 and/or IPv6 in any combination.
195 */
196 retval = NULL;
197
198 /* Convert the provided bind address list to raw format. */
199 addrs = sctp_bind_addrs_to_raw(bp, &addrs_len, gfp);
200
201 init.init_tag = htonl(asoc->c.my_vtag);
202 init.a_rwnd = htonl(asoc->rwnd);
203 init.num_outbound_streams = htons(asoc->c.sinit_num_ostreams);
204 init.num_inbound_streams = htons(asoc->c.sinit_max_instreams);
205 init.initial_tsn = htonl(asoc->c.initial_tsn);
206
207 /* How many address types are needed? */
208 sp = sctp_sk(asoc->base.sk);
209 num_types = sp->pf->supported_addrs(sp, types);
210
a8170c35
WY		 211 chunksize = sizeof(init) + addrs_len;
212 chunksize += WORD_ROUND(SCTP_SAT_LEN(num_types));
1da177e4 213 chunksize += sizeof(ecap_param);
8ee4be37 214
036b579b
VY		 215 if (sctp_prsctp_enable)
216 chunksize += sizeof(prsctp_param);
217
131a47e3
VY		 218 /* ADDIP: Section 4.2.7:
219 * An implementation supporting this extension [ADDIP] MUST list
220 * the ASCONF,the ASCONF-ACK, and the AUTH chunks in its INIT and
221 * INIT-ACK parameters.
131a47e3
VY		 222 */
223 if (sctp_addip_enable) {
224 extensions[num_ext] = SCTP_CID_ASCONF;
225 extensions[num_ext+1] = SCTP_CID_ASCONF_ACK;
226 num_ext += 2;
227 }
228
6fc791ee 229 if (sp->adaptation_ind)
230 chunksize += sizeof(aiparam);
231
1da177e4
LT		 232 chunksize += vparam_len;
233
730fc3d0
VY		 234 /* Account for AUTH related parameters */
235 if (sctp_auth_enable) {
236 /* Add random parameter length*/
237 chunksize += sizeof(asoc->c.auth_random);
238
239 /* Add HMACS parameter length if any were defined */
240 auth_hmacs = (sctp_paramhdr_t *)asoc->c.auth_hmacs;
241 if (auth_hmacs->length)
a8170c35 242 chunksize += WORD_ROUND(ntohs(auth_hmacs->length));
730fc3d0
VY		 243 else
244 auth_hmacs = NULL;
245
246 /* Add CHUNKS parameter length */
247 auth_chunks = (sctp_paramhdr_t *)asoc->c.auth_chunks;
248 if (auth_chunks->length)
a8170c35 249 chunksize += WORD_ROUND(ntohs(auth_chunks->length));
730fc3d0 250 else
9baffaa6 251 auth_chunks = NULL;
730fc3d0
VY		 252
253 extensions[num_ext] = SCTP_CID_AUTH;
254 num_ext += 1;
255 }
256
131a47e3
VY		 257 /* If we have any extensions to report, account for that */
258 if (num_ext)
a8170c35
WY		 259 chunksize += WORD_ROUND(sizeof(sctp_supported_ext_param_t) +
260 num_ext);
131a47e3 261
1da177e4
LT		 262 /* RFC 2960 3.3.2 Initiation (INIT) (1)
263 *
264 * Note 3: An INIT chunk MUST NOT contain more than one Host
265 * Name address parameter. Moreover, the sender of the INIT
266 * MUST NOT combine any other address types with the Host Name
267 * address in the INIT. The receiver of INIT MUST ignore any
268 * other address types if the Host Name address parameter is
269 * present in the received INIT chunk.
270 *
271 * PLEASE DO NOT FIXME [This version does not support Host Name.]
272 */
273
274 retval = sctp_make_chunk(asoc, SCTP_CID_INIT, 0, chunksize);
275 if (!retval)
276 goto nodata;
277
278 retval->subh.init_hdr =
279 sctp_addto_chunk(retval, sizeof(init), &init);
280 retval->param_hdr.v =
281 sctp_addto_chunk(retval, addrs_len, addrs.v);
282
283 /* RFC 2960 3.3.2 Initiation (INIT) (1)
284 *
285 * Note 4: This parameter, when present, specifies all the
286 * address types the sending endpoint can support. The absence
287 * of this parameter indicates that the sending endpoint can
288 * support any address type.
289 */
290 sat.param_hdr.type = SCTP_PARAM_SUPPORTED_ADDRESS_TYPES;
291 sat.param_hdr.length = htons(SCTP_SAT_LEN(num_types));
292 sctp_addto_chunk(retval, sizeof(sat), &sat);
293 sctp_addto_chunk(retval, num_types * sizeof(__u16), &types);
294
295 sctp_addto_chunk(retval, sizeof(ecap_param), &ecap_param);
131a47e3 296
7aa1b54b 297 /* Add the supported extensions parameter. Be nice and add this
131a47e3
VY		 298 * fist before addiding the parameters for the extensions themselves
299 */
300 if (num_ext) {
301 ext_param.param_hdr.type = SCTP_PARAM_SUPPORTED_EXT;
302 ext_param.param_hdr.length =
303 htons(sizeof(sctp_supported_ext_param_t) + num_ext);
304 sctp_addto_chunk(retval, sizeof(sctp_supported_ext_param_t),
305 &ext_param);
8ee4be37 306 sctp_addto_param(retval, num_ext, extensions);
131a47e3
VY		 307 }
308
1da177e4
LT		 309 if (sctp_prsctp_enable)
310 sctp_addto_chunk(retval, sizeof(prsctp_param), &prsctp_param);
131a47e3 311
6fc791ee 312 if (sp->adaptation_ind) {
313 aiparam.param_hdr.type = SCTP_PARAM_ADAPTATION_LAYER_IND;
314 aiparam.param_hdr.length = htons(sizeof(aiparam));
315 aiparam.adaptation_ind = htonl(sp->adaptation_ind);
316 sctp_addto_chunk(retval, sizeof(aiparam), &aiparam);
317 }
131a47e3 318
730fc3d0
VY		 319 /* Add SCTP-AUTH chunks to the parameter list */
320 if (sctp_auth_enable) {
321 sctp_addto_chunk(retval, sizeof(asoc->c.auth_random),
322 asoc->c.auth_random);
323 if (auth_hmacs)
324 sctp_addto_chunk(retval, ntohs(auth_hmacs->length),
325 auth_hmacs);
326 if (auth_chunks)
327 sctp_addto_chunk(retval, ntohs(auth_chunks->length),
328 auth_chunks);
329 }
1da177e4 330nodata:
a51482bd 331 kfree(addrs.v);
1da177e4
LT		 332 return retval;
333}
334
335struct sctp_chunk *sctp_make_init_ack(const struct sctp_association *asoc,
336 const struct sctp_chunk *chunk,
dd0fc66f 337 gfp_t gfp, int unkparam_len)
1da177e4
LT		 338{
339 sctp_inithdr_t initack;
340 struct sctp_chunk *retval;
341 union sctp_params addrs;
6fc791ee 342 struct sctp_sock *sp;
1da177e4
LT		 343 int addrs_len;
344 sctp_cookie_param_t *cookie;
345 int cookie_len;
346 size_t chunksize;
0f3fffd8 347 sctp_adaptation_ind_param_t aiparam;
131a47e3
VY		 348 sctp_supported_ext_param_t ext_param;
349 int num_ext = 0;
350 __u8 extensions[3];
730fc3d0
VY		 351 sctp_paramhdr_t *auth_chunks = NULL,
352 *auth_hmacs = NULL,
353 *auth_random = NULL;
1da177e4
LT		 354
355 retval = NULL;
356
357 /* Note: there may be no addresses to embed. */
358 addrs = sctp_bind_addrs_to_raw(&asoc->base.bind_addr, &addrs_len, gfp);
359
360 initack.init_tag = htonl(asoc->c.my_vtag);
361 initack.a_rwnd = htonl(asoc->rwnd);
362 initack.num_outbound_streams = htons(asoc->c.sinit_num_ostreams);
363 initack.num_inbound_streams = htons(asoc->c.sinit_max_instreams);
364 initack.initial_tsn = htonl(asoc->c.initial_tsn);
365
366 /* FIXME: We really ought to build the cookie right
367 * into the packet instead of allocating more fresh memory.
368 */
369 cookie = sctp_pack_cookie(asoc->ep, asoc, chunk, &cookie_len,
370 addrs.v, addrs_len);
371 if (!cookie)
372 goto nomem_cookie;
373
374 /* Calculate the total size of allocation, include the reserved
375 * space for reporting unknown parameters if it is specified.
376 */
6fc791ee 377 sp = sctp_sk(asoc->base.sk);
1da177e4
LT		 378 chunksize = sizeof(initack) + addrs_len + cookie_len + unkparam_len;
379
d808ad9a 380 /* Tell peer that we'll do ECN only if peer advertised such cap. */
1da177e4
LT		 381 if (asoc->peer.ecn_capable)
382 chunksize += sizeof(ecap_param);
383
5ffad5ac 384 if (asoc->peer.prsctp_capable)
036b579b
VY		 385 chunksize += sizeof(prsctp_param);
386
5ffad5ac 387 if (asoc->peer.asconf_capable) {
131a47e3
VY		 388 extensions[num_ext] = SCTP_CID_ASCONF;
389 extensions[num_ext+1] = SCTP_CID_ASCONF_ACK;
390 num_ext += 2;
391 }
392
6fc791ee 393 if (sp->adaptation_ind)
394 chunksize += sizeof(aiparam);
1da177e4 395
730fc3d0
VY		 396 if (asoc->peer.auth_capable) {
397 auth_random = (sctp_paramhdr_t *)asoc->c.auth_random;
398 chunksize += ntohs(auth_random->length);
399
400 auth_hmacs = (sctp_paramhdr_t *)asoc->c.auth_hmacs;
401 if (auth_hmacs->length)
a8170c35 402 chunksize += WORD_ROUND(ntohs(auth_hmacs->length));
730fc3d0
VY		 403 else
404 auth_hmacs = NULL;
405
406 auth_chunks = (sctp_paramhdr_t *)asoc->c.auth_chunks;
407 if (auth_chunks->length)
a8170c35 408 chunksize += WORD_ROUND(ntohs(auth_chunks->length));
730fc3d0
VY		 409 else
410 auth_chunks = NULL;
411
412 extensions[num_ext] = SCTP_CID_AUTH;
413 num_ext += 1;
414 }
415
8ee4be37 416 if (num_ext)
a8170c35
WY		 417 chunksize += WORD_ROUND(sizeof(sctp_supported_ext_param_t) +
418 num_ext);
8ee4be37 419
1da177e4
LT		 420 /* Now allocate and fill out the chunk. */
421 retval = sctp_make_chunk(asoc, SCTP_CID_INIT_ACK, 0, chunksize);
422 if (!retval)
423 goto nomem_chunk;
424
425 /* Per the advice in RFC 2960 6.4, send this reply to
426 * the source of the INIT packet.
427 */
428 retval->transport = chunk->transport;
429 retval->subh.init_hdr =
430 sctp_addto_chunk(retval, sizeof(initack), &initack);
431 retval->param_hdr.v = sctp_addto_chunk(retval, addrs_len, addrs.v);
432 sctp_addto_chunk(retval, cookie_len, cookie);
433 if (asoc->peer.ecn_capable)
434 sctp_addto_chunk(retval, sizeof(ecap_param), &ecap_param);
131a47e3
VY		 435 if (num_ext) {
436 ext_param.param_hdr.type = SCTP_PARAM_SUPPORTED_EXT;
437 ext_param.param_hdr.length =
438 htons(sizeof(sctp_supported_ext_param_t) + num_ext);
439 sctp_addto_chunk(retval, sizeof(sctp_supported_ext_param_t),
440 &ext_param);
8ee4be37 441 sctp_addto_param(retval, num_ext, extensions);
131a47e3 442 }
1da177e4
LT		 443 if (asoc->peer.prsctp_capable)
444 sctp_addto_chunk(retval, sizeof(prsctp_param), &prsctp_param);
445
6fc791ee 446 if (sp->adaptation_ind) {
447 aiparam.param_hdr.type = SCTP_PARAM_ADAPTATION_LAYER_IND;
448 aiparam.param_hdr.length = htons(sizeof(aiparam));
449 aiparam.adaptation_ind = htonl(sp->adaptation_ind);
450 sctp_addto_chunk(retval, sizeof(aiparam), &aiparam);
451 }
1da177e4 452
730fc3d0
VY		 453 if (asoc->peer.auth_capable) {
454 sctp_addto_chunk(retval, ntohs(auth_random->length),
455 auth_random);
456 if (auth_hmacs)
457 sctp_addto_chunk(retval, ntohs(auth_hmacs->length),
458 auth_hmacs);
459 if (auth_chunks)
460 sctp_addto_chunk(retval, ntohs(auth_chunks->length),
461 auth_chunks);
462 }
463
1da177e4
LT		 464 /* We need to remove the const qualifier at this point. */
465 retval->asoc = (struct sctp_association *) asoc;
466
467 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
468 *
469 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
470 * HEARTBEAT ACK, * etc.) to the same destination transport
471 * address from which it received the DATA or control chunk
472 * to which it is replying.
473 *
474 * [INIT ACK back to where the INIT came from.]
475 */
476 if (chunk)
477 retval->transport = chunk->transport;
478
479nomem_chunk:
480 kfree(cookie);
481nomem_cookie:
a51482bd 482 kfree(addrs.v);
1da177e4
LT		 483 return retval;
484}
485
486/* 3.3.11 Cookie Echo (COOKIE ECHO) (10):
487 *
488 * This chunk is used only during the initialization of an association.
489 * It is sent by the initiator of an association to its peer to complete
490 * the initialization process. This chunk MUST precede any DATA chunk
491 * sent within the association, but MAY be bundled with one or more DATA
492 * chunks in the same packet.
493 *
494 * 0 1 2 3
495 * 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
496 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
497 * | Type = 10 |Chunk Flags | Length |
498 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
499 * / Cookie /
500 * \ \
501 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
502 *
503 * Chunk Flags: 8 bit
504 *
505 * Set to zero on transmit and ignored on receipt.
506 *
507 * Length: 16 bits (unsigned integer)
508 *
509 * Set to the size of the chunk in bytes, including the 4 bytes of
510 * the chunk header and the size of the Cookie.
511 *
512 * Cookie: variable size
513 *
514 * This field must contain the exact cookie received in the
515 * State Cookie parameter from the previous INIT ACK.
516 *
517 * An implementation SHOULD make the cookie as small as possible
518 * to insure interoperability.
519 */
520struct sctp_chunk *sctp_make_cookie_echo(const struct sctp_association *asoc,
521 const struct sctp_chunk *chunk)
522{
523 struct sctp_chunk *retval;
524 void *cookie;
525 int cookie_len;
526
527 cookie = asoc->peer.cookie;
528 cookie_len = asoc->peer.cookie_len;
529
530 /* Build a cookie echo chunk. */
531 retval = sctp_make_chunk(asoc, SCTP_CID_COOKIE_ECHO, 0, cookie_len);
532 if (!retval)
533 goto nodata;
534 retval->subh.cookie_hdr =
535 sctp_addto_chunk(retval, cookie_len, cookie);
536
537 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
538 *
539 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
540 * HEARTBEAT ACK, * etc.) to the same destination transport
541 * address from which it * received the DATA or control chunk
542 * to which it is replying.
543 *
544 * [COOKIE ECHO back to where the INIT ACK came from.]
545 */
546 if (chunk)
547 retval->transport = chunk->transport;
548
549nodata:
550 return retval;
551}
552
553/* 3.3.12 Cookie Acknowledgement (COOKIE ACK) (11):
554 *
555 * This chunk is used only during the initialization of an
556 * association. It is used to acknowledge the receipt of a COOKIE
557 * ECHO chunk. This chunk MUST precede any DATA or SACK chunk sent
558 * within the association, but MAY be bundled with one or more DATA
559 * chunks or SACK chunk in the same SCTP packet.
560 *
561 * 0 1 2 3
562 * 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
563 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
564 * | Type = 11 |Chunk Flags | Length = 4 |
565 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
566 *
567 * Chunk Flags: 8 bits
568 *
569 * Set to zero on transmit and ignored on receipt.
570 */
571struct sctp_chunk *sctp_make_cookie_ack(const struct sctp_association *asoc,
572 const struct sctp_chunk *chunk)
573{
574 struct sctp_chunk *retval;
575
576 retval = sctp_make_chunk(asoc, SCTP_CID_COOKIE_ACK, 0, 0);
577
578 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
579 *
580 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
581 * HEARTBEAT ACK, * etc.) to the same destination transport
582 * address from which it * received the DATA or control chunk
583 * to which it is replying.
584 *
585 * [COOKIE ACK back to where the COOKIE ECHO came from.]
586 */
587 if (retval && chunk)
588 retval->transport = chunk->transport;
589
590 return retval;
591}
592
593/*
594 * Appendix A: Explicit Congestion Notification:
595 * CWR:
596 *
597 * RFC 2481 details a specific bit for a sender to send in the header of
598 * its next outbound TCP segment to indicate to its peer that it has
599 * reduced its congestion window. This is termed the CWR bit. For
600 * SCTP the same indication is made by including the CWR chunk.
601 * This chunk contains one data element, i.e. the TSN number that
602 * was sent in the ECNE chunk. This element represents the lowest
603 * TSN number in the datagram that was originally marked with the
604 * CE bit.
605 *
606 * 0 1 2 3
607 * 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
608 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
609 * | Chunk Type=13 | Flags=00000000| Chunk Length = 8 |
610 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
611 * | Lowest TSN Number |
612 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
613 *
614 * Note: The CWR is considered a Control chunk.
615 */
616struct sctp_chunk *sctp_make_cwr(const struct sctp_association *asoc,
617 const __u32 lowest_tsn,
618 const struct sctp_chunk *chunk)
619{
620 struct sctp_chunk *retval;
621 sctp_cwrhdr_t cwr;
622
623 cwr.lowest_tsn = htonl(lowest_tsn);
624 retval = sctp_make_chunk(asoc, SCTP_CID_ECN_CWR, 0,
625 sizeof(sctp_cwrhdr_t));
626
627 if (!retval)
628 goto nodata;
629
630 retval->subh.ecn_cwr_hdr =
631 sctp_addto_chunk(retval, sizeof(cwr), &cwr);
632
633 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
634 *
635 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
636 * HEARTBEAT ACK, * etc.) to the same destination transport
637 * address from which it * received the DATA or control chunk
638 * to which it is replying.
639 *
640 * [Report a reduced congestion window back to where the ECNE
641 * came from.]
642 */
643 if (chunk)
644 retval->transport = chunk->transport;
645
646nodata:
647 return retval;
648}
649
650/* Make an ECNE chunk. This is a congestion experienced report. */
651struct sctp_chunk *sctp_make_ecne(const struct sctp_association *asoc,
652 const __u32 lowest_tsn)
653{
654 struct sctp_chunk *retval;
655 sctp_ecnehdr_t ecne;
656
657 ecne.lowest_tsn = htonl(lowest_tsn);
658 retval = sctp_make_chunk(asoc, SCTP_CID_ECN_ECNE, 0,
659 sizeof(sctp_ecnehdr_t));
660 if (!retval)
661 goto nodata;
662 retval->subh.ecne_hdr =
663 sctp_addto_chunk(retval, sizeof(ecne), &ecne);
664
665nodata:
666 return retval;
667}
668
669/* Make a DATA chunk for the given association from the provided
670 * parameters. However, do not populate the data payload.
671 */
672struct sctp_chunk *sctp_make_datafrag_empty(struct sctp_association *asoc,
673 const struct sctp_sndrcvinfo *sinfo,
674 int data_len, __u8 flags, __u16 ssn)
675{
676 struct sctp_chunk *retval;
677 struct sctp_datahdr dp;
678 int chunk_len;
679
680 /* We assign the TSN as LATE as possible, not here when
681 * creating the chunk.
682 */
683 dp.tsn = 0;
684 dp.stream = htons(sinfo->sinfo_stream);
685 dp.ppid = sinfo->sinfo_ppid;
686
687 /* Set the flags for an unordered send. */
eaa5c54d 688 if (sinfo->sinfo_flags & SCTP_UNORDERED) {
1da177e4
LT		 689 flags |= SCTP_DATA_UNORDERED;
690 dp.ssn = 0;
691 } else
692 dp.ssn = htons(ssn);
693
694 chunk_len = sizeof(dp) + data_len;
695 retval = sctp_make_chunk(asoc, SCTP_CID_DATA, flags, chunk_len);
696 if (!retval)
697 goto nodata;
698
699 retval->subh.data_hdr = sctp_addto_chunk(retval, sizeof(dp), &dp);
700 memcpy(&retval->sinfo, sinfo, sizeof(struct sctp_sndrcvinfo));
701
702nodata:
703 return retval;
704}
705
706/* Create a selective ackowledgement (SACK) for the given
707 * association. This reports on which TSN's we've seen to date,
708 * including duplicates and gaps.
709 */
710struct sctp_chunk *sctp_make_sack(const struct sctp_association *asoc)
711{
712 struct sctp_chunk *retval;
713 struct sctp_sackhdr sack;
714 int len;
715 __u32 ctsn;
716 __u16 num_gabs, num_dup_tsns;
717 struct sctp_tsnmap *map = (struct sctp_tsnmap *)&asoc->peer.tsn_map;
02015180 718 struct sctp_gap_ack_block gabs[SCTP_MAX_GABS];
1da177e4 719
02015180 720 memset(gabs, 0, sizeof(gabs));
1da177e4
LT		 721 ctsn = sctp_tsnmap_get_ctsn(map);
722 SCTP_DEBUG_PRINTK("sackCTSNAck sent: 0x%x.\n", ctsn);
723
724 /* How much room is needed in the chunk? */
02015180 725 num_gabs = sctp_tsnmap_num_gabs(map, gabs);
1da177e4
LT		 726 num_dup_tsns = sctp_tsnmap_num_dups(map);
727
728 /* Initialize the SACK header. */
729 sack.cum_tsn_ack = htonl(ctsn);
730 sack.a_rwnd = htonl(asoc->a_rwnd);
731 sack.num_gap_ack_blocks = htons(num_gabs);
732 sack.num_dup_tsns = htons(num_dup_tsns);
733
734 len = sizeof(sack)
735 + sizeof(struct sctp_gap_ack_block) * num_gabs
736 + sizeof(__u32) * num_dup_tsns;
737
738 /* Create the chunk. */
739 retval = sctp_make_chunk(asoc, SCTP_CID_SACK, 0, len);
740 if (!retval)
741 goto nodata;
742
743 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
744 *
745 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
746 * HEARTBEAT ACK, etc.) to the same destination transport
747 * address from which it received the DATA or control chunk to
748 * which it is replying. This rule should also be followed if
749 * the endpoint is bundling DATA chunks together with the
750 * reply chunk.
751 *
752 * However, when acknowledging multiple DATA chunks received
753 * in packets from different source addresses in a single
754 * SACK, the SACK chunk may be transmitted to one of the
755 * destination transport addresses from which the DATA or
756 * control chunks being acknowledged were received.
757 *
758 * [BUG: We do not implement the following paragraph.
759 * Perhaps we should remember the last transport we used for a
760 * SACK and avoid that (if possible) if we have seen any
761 * duplicates. --piggy]
762 *
763 * When a receiver of a duplicate DATA chunk sends a SACK to a
764 * multi- homed endpoint it MAY be beneficial to vary the
765 * destination address and not use the source address of the
766 * DATA chunk. The reason being that receiving a duplicate
767 * from a multi-homed endpoint might indicate that the return
768 * path (as specified in the source address of the DATA chunk)
769 * for the SACK is broken.
770 *
771 * [Send to the address from which we last received a DATA chunk.]
772 */
773 retval->transport = asoc->peer.last_data_from;
774
775 retval->subh.sack_hdr =
776 sctp_addto_chunk(retval, sizeof(sack), &sack);
777
778 /* Add the gap ack block information. */
779 if (num_gabs)
780 sctp_addto_chunk(retval, sizeof(__u32) * num_gabs,
02015180 781 gabs);
1da177e4
LT		 782
783 /* Add the duplicate TSN information. */
784 if (num_dup_tsns)
785 sctp_addto_chunk(retval, sizeof(__u32) * num_dup_tsns,
786 sctp_tsnmap_get_dups(map));
787
788nodata:
789 return retval;
790}
791
792/* Make a SHUTDOWN chunk. */
793struct sctp_chunk *sctp_make_shutdown(const struct sctp_association *asoc,
794 const struct sctp_chunk *chunk)
795{
796 struct sctp_chunk *retval;
797 sctp_shutdownhdr_t shut;
798 __u32 ctsn;
799
800 ctsn = sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map);
801 shut.cum_tsn_ack = htonl(ctsn);
802
803 retval = sctp_make_chunk(asoc, SCTP_CID_SHUTDOWN, 0,
804 sizeof(sctp_shutdownhdr_t));
805 if (!retval)
806 goto nodata;
807
808 retval->subh.shutdown_hdr =
809 sctp_addto_chunk(retval, sizeof(shut), &shut);
810
811 if (chunk)
812 retval->transport = chunk->transport;
813nodata:
814 return retval;
815}
816
817struct sctp_chunk *sctp_make_shutdown_ack(const struct sctp_association *asoc,
818 const struct sctp_chunk *chunk)
819{
820 struct sctp_chunk *retval;
821
822 retval = sctp_make_chunk(asoc, SCTP_CID_SHUTDOWN_ACK, 0, 0);
823
824 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
825 *
826 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
827 * HEARTBEAT ACK, * etc.) to the same destination transport
828 * address from which it * received the DATA or control chunk
829 * to which it is replying.
830 *
831 * [ACK back to where the SHUTDOWN came from.]
832 */
833 if (retval && chunk)
834 retval->transport = chunk->transport;
835
836 return retval;
837}
838
839struct sctp_chunk *sctp_make_shutdown_complete(
840 const struct sctp_association *asoc,
841 const struct sctp_chunk *chunk)
842{
843 struct sctp_chunk *retval;
844 __u8 flags = 0;
845
047a2428
JF		 846 /* Set the T-bit if we have no association (vtag will be
847 * reflected)
848 */
1da177e4
LT		 849 flags |= asoc ? 0 : SCTP_CHUNK_FLAG_T;
850
851 retval = sctp_make_chunk(asoc, SCTP_CID_SHUTDOWN_COMPLETE, flags, 0);
852
853 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
854 *
855 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
856 * HEARTBEAT ACK, * etc.) to the same destination transport
857 * address from which it * received the DATA or control chunk
858 * to which it is replying.
859 *
860 * [Report SHUTDOWN COMPLETE back to where the SHUTDOWN ACK
861 * came from.]
862 */
863 if (retval && chunk)
864 retval->transport = chunk->transport;
865
d808ad9a 866 return retval;
1da177e4
LT		 867}
868
869/* Create an ABORT. Note that we set the T bit if we have no
047a2428 870 * association, except when responding to an INIT (sctpimpguide 2.41).
1da177e4
LT		 871 */
872struct sctp_chunk *sctp_make_abort(const struct sctp_association *asoc,
873 const struct sctp_chunk *chunk,
874 const size_t hint)
875{
876 struct sctp_chunk *retval;
877 __u8 flags = 0;
878
047a2428
JF		 879 /* Set the T-bit if we have no association and 'chunk' is not
880 * an INIT (vtag will be reflected).
881 */
882 if (!asoc) {
883 if (chunk && chunk->chunk_hdr &&
884 chunk->chunk_hdr->type == SCTP_CID_INIT)
885 flags = 0;
886 else
887 flags = SCTP_CHUNK_FLAG_T;
888 }
1da177e4
LT		 889
890 retval = sctp_make_chunk(asoc, SCTP_CID_ABORT, flags, hint);
891
892 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
893 *
894 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
895 * HEARTBEAT ACK, * etc.) to the same destination transport
896 * address from which it * received the DATA or control chunk
897 * to which it is replying.
898 *
899 * [ABORT back to where the offender came from.]
900 */
901 if (retval && chunk)
902 retval->transport = chunk->transport;
903
904 return retval;
905}
906
907/* Helper to create ABORT with a NO_USER_DATA error. */
908struct sctp_chunk *sctp_make_abort_no_data(
909 const struct sctp_association *asoc,
910 const struct sctp_chunk *chunk, __u32 tsn)
911{
912 struct sctp_chunk *retval;
9f81bcd9 913 __be32 payload;
1da177e4
LT		 914
915 retval = sctp_make_abort(asoc, chunk, sizeof(sctp_errhdr_t)
916 + sizeof(tsn));
917
918 if (!retval)
919 goto no_mem;
920
921 /* Put the tsn back into network byte order. */
922 payload = htonl(tsn);
00f1c2df
WY		 923 sctp_init_cause(retval, SCTP_ERROR_NO_DATA, sizeof(payload));
924 sctp_addto_chunk(retval, sizeof(payload), (const void *)&payload);
1da177e4
LT		 925
926 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
927 *
928 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
929 * HEARTBEAT ACK, * etc.) to the same destination transport
930 * address from which it * received the DATA or control chunk
931 * to which it is replying.
932 *
933 * [ABORT back to where the offender came from.]
934 */
935 if (chunk)
936 retval->transport = chunk->transport;
937
938no_mem:
939 return retval;
940}
941
942/* Helper to create ABORT with a SCTP_ERROR_USER_ABORT error. */
943struct sctp_chunk *sctp_make_abort_user(const struct sctp_association *asoc,
c164a9ba
SS		 944 const struct msghdr *msg,
945 size_t paylen)
1da177e4
LT		 946{
947 struct sctp_chunk *retval;
c164a9ba
SS		 948 void *payload = NULL;
949 int err;
1da177e4 950
c164a9ba 951 retval = sctp_make_abort(asoc, NULL, sizeof(sctp_errhdr_t) + paylen);
1da177e4
LT		 952 if (!retval)
953 goto err_chunk;
954
955 if (paylen) {
956 /* Put the msg_iov together into payload. */
c164a9ba 957 payload = kmalloc(paylen, GFP_KERNEL);
1da177e4
LT		 958 if (!payload)
959 goto err_payload;
c164a9ba
SS		 960
961 err = memcpy_fromiovec(payload, msg->msg_iov, paylen);
962 if (err < 0)
963 goto err_copy;
1da177e4
LT		 964 }
965
00f1c2df
WY		 966 sctp_init_cause(retval, SCTP_ERROR_USER_ABORT, paylen);
967 sctp_addto_chunk(retval, paylen, payload);
1da177e4
LT		 968
969 if (paylen)
970 kfree(payload);
971
972 return retval;
973
974err_copy:
975 kfree(payload);
976err_payload:
977 sctp_chunk_free(retval);
978 retval = NULL;
979err_chunk:
980 return retval;
981}
982
5c94bf86
AB		 983/* Append bytes to the end of a parameter. Will panic if chunk is not big
984 * enough.
985 */
986static void *sctp_addto_param(struct sctp_chunk *chunk, int len,
987 const void *data)
988{
989 void *target;
990 int chunklen = ntohs(chunk->chunk_hdr->length);
991
992 target = skb_put(chunk->skb, len);
993
6383cfb3
VY		 994 if (data)
995 memcpy(target, data, len);
996 else
997 memset(target, 0, len);
5c94bf86
AB		 998
999 /* Adjust the chunk length field. */
1000 chunk->chunk_hdr->length = htons(chunklen + len);
1001 chunk->chunk_end = skb_tail_pointer(chunk->skb);
1002
1003 return target;
1004}
1005
d808ad9a 1006/* Make an ABORT chunk with a PROTOCOL VIOLATION cause code. */
1da177e4
LT		 1007struct sctp_chunk *sctp_make_abort_violation(
1008 const struct sctp_association *asoc,
1009 const struct sctp_chunk *chunk,
1010 const __u8 *payload,
1011 const size_t paylen)
1012{
1013 struct sctp_chunk *retval;
1014 struct sctp_paramhdr phdr;
1015
1016 retval = sctp_make_abort(asoc, chunk, sizeof(sctp_errhdr_t) + paylen
00f1c2df 1017 + sizeof(sctp_paramhdr_t));
1da177e4
LT		 1018 if (!retval)
1019 goto end;
1020
00f1c2df
WY		 1021 sctp_init_cause(retval, SCTP_ERROR_PROTO_VIOLATION, paylen
1022 + sizeof(sctp_paramhdr_t));
1da177e4
LT		 1023
1024 phdr.type = htons(chunk->chunk_hdr->type);
1025 phdr.length = chunk->chunk_hdr->length;
00f1c2df
WY		 1026 sctp_addto_chunk(retval, paylen, payload);
1027 sctp_addto_param(retval, sizeof(sctp_paramhdr_t), &phdr);
1da177e4
LT		 1028
1029end:
1030 return retval;
1031}
1032
ba016670
WY		 1033struct sctp_chunk *sctp_make_violation_paramlen(
1034 const struct sctp_association *asoc,
1035 const struct sctp_chunk *chunk,
1036 struct sctp_paramhdr *param)
1037{
1038 struct sctp_chunk *retval;
1039 static const char error[] = "The following parameter had invalid length:";
1040 size_t payload_len = sizeof(error) + sizeof(sctp_errhdr_t) +
1041 sizeof(sctp_paramhdr_t);
1042
1043 retval = sctp_make_abort(asoc, chunk, payload_len);
1044 if (!retval)
1045 goto nodata;
1046
1047 sctp_init_cause(retval, SCTP_ERROR_PROTO_VIOLATION,
1048 sizeof(error) + sizeof(sctp_paramhdr_t));
1049 sctp_addto_chunk(retval, sizeof(error), error);
1050 sctp_addto_param(retval, sizeof(sctp_paramhdr_t), param);
1051
1052nodata:
1053 return retval;
1054}
1055
1da177e4
LT		 1056/* Make a HEARTBEAT chunk. */
1057struct sctp_chunk *sctp_make_heartbeat(const struct sctp_association *asoc,
1058 const struct sctp_transport *transport,
1059 const void *payload, const size_t paylen)
1060{
1061 struct sctp_chunk *retval = sctp_make_chunk(asoc, SCTP_CID_HEARTBEAT,
1062 0, paylen);
1063
1064 if (!retval)
1065 goto nodata;
1066
1067 /* Cast away the 'const', as this is just telling the chunk
1068 * what transport it belongs to.
1069 */
1070 retval->transport = (struct sctp_transport *) transport;
1071 retval->subh.hbs_hdr = sctp_addto_chunk(retval, paylen, payload);
1072
1073nodata:
1074 return retval;
1075}
1076
1077struct sctp_chunk *sctp_make_heartbeat_ack(const struct sctp_association *asoc,
1078 const struct sctp_chunk *chunk,
1079 const void *payload, const size_t paylen)
1080{
1081 struct sctp_chunk *retval;
1082
1083 retval = sctp_make_chunk(asoc, SCTP_CID_HEARTBEAT_ACK, 0, paylen);
1084 if (!retval)
1085 goto nodata;
1086
1087 retval->subh.hbs_hdr = sctp_addto_chunk(retval, paylen, payload);
1088
1089 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
1090 *
1091 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
1092 * HEARTBEAT ACK, * etc.) to the same destination transport
1093 * address from which it * received the DATA or control chunk
1094 * to which it is replying.
1095 *
1096 * [HBACK back to where the HEARTBEAT came from.]
1097 */
1098 if (chunk)
1099 retval->transport = chunk->transport;
1100
1101nodata:
1102 return retval;
1103}
1104
1105/* Create an Operation Error chunk with the specified space reserved.
1106 * This routine can be used for containing multiple causes in the chunk.
1107 */
1108static struct sctp_chunk *sctp_make_op_error_space(
1109 const struct sctp_association *asoc,
1110 const struct sctp_chunk *chunk,
1111 size_t size)
1112{
1113 struct sctp_chunk *retval;
1114
1115 retval = sctp_make_chunk(asoc, SCTP_CID_ERROR, 0,
1116 sizeof(sctp_errhdr_t) + size);
1117 if (!retval)
1118 goto nodata;
1119
1120 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
1121 *
1122 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
1123 * HEARTBEAT ACK, etc.) to the same destination transport
1124 * address from which it received the DATA or control chunk
1125 * to which it is replying.
1126 *
1127 */
1128 if (chunk)
1129 retval->transport = chunk->transport;
1130
1131nodata:
1132 return retval;
1133}
1134
1135/* Create an Operation Error chunk. */
1136struct sctp_chunk *sctp_make_op_error(const struct sctp_association *asoc,
1137 const struct sctp_chunk *chunk,
63706c5c 1138 __be16 cause_code, const void *payload,
6383cfb3 1139 size_t paylen, size_t reserve_tail)
1da177e4
LT		 1140{
1141 struct sctp_chunk *retval;
1142
6383cfb3 1143 retval = sctp_make_op_error_space(asoc, chunk, paylen + reserve_tail);
1da177e4
LT		 1144 if (!retval)
1145 goto nodata;
1146
6383cfb3 1147 sctp_init_cause(retval, cause_code, paylen + reserve_tail);
00f1c2df 1148 sctp_addto_chunk(retval, paylen, payload);
6383cfb3
VY		 1149 if (reserve_tail)
1150 sctp_addto_param(retval, reserve_tail, NULL);
1da177e4
LT		 1151
1152nodata:
1153 return retval;
1154}
1155
4cd57c80
VY		 1156struct sctp_chunk *sctp_make_auth(const struct sctp_association *asoc)
1157{
1158 struct sctp_chunk *retval;
1159 struct sctp_hmac *hmac_desc;
1160 struct sctp_authhdr auth_hdr;
1161 __u8 *hmac;
1162
1163 /* Get the first hmac that the peer told us to use */
1164 hmac_desc = sctp_auth_asoc_get_hmac(asoc);
1165 if (unlikely(!hmac_desc))
1166 return NULL;
1167
1168 retval = sctp_make_chunk(asoc, SCTP_CID_AUTH, 0,
1169 hmac_desc->hmac_len + sizeof(sctp_authhdr_t));
1170 if (!retval)
1171 return NULL;
1172
1173 auth_hdr.hmac_id = htons(hmac_desc->hmac_id);
1174 auth_hdr.shkey_id = htons(asoc->active_key_id);
1175
1176 retval->subh.auth_hdr = sctp_addto_chunk(retval, sizeof(sctp_authhdr_t),
1177 &auth_hdr);
1178
1179 hmac = skb_put(retval->skb, hmac_desc->hmac_len);
1180 memset(hmac, 0, hmac_desc->hmac_len);
1181
1182 /* Adjust the chunk header to include the empty MAC */
1183 retval->chunk_hdr->length =
1184 htons(ntohs(retval->chunk_hdr->length) + hmac_desc->hmac_len);
1185 retval->chunk_end = skb_tail_pointer(retval->skb);
1186
1187 return retval;
1188}
1189
1190
1da177e4
LT		 1191/********************************************************************
1192 * 2nd Level Abstractions
1193 ********************************************************************/
1194
1195/* Turn an skb into a chunk.
1196 * FIXME: Eventually move the structure directly inside the skb->cb[].
1197 */
1198struct sctp_chunk *sctp_chunkify(struct sk_buff *skb,
1199 const struct sctp_association *asoc,
1200 struct sock *sk)
1201{
1202 struct sctp_chunk *retval;
1203
c3762229 1204 retval = kmem_cache_zalloc(sctp_chunk_cachep, GFP_ATOMIC);
1da177e4
LT		 1205
1206 if (!retval)
1207 goto nodata;
1da177e4
LT		 1208
1209 if (!sk) {
1210 SCTP_DEBUG_PRINTK("chunkifying skb %p w/o an sk\n", skb);
1211 }
1212
79af02c2 1213 INIT_LIST_HEAD(&retval->list);
1da177e4
LT		 1214 retval->skb = skb;
1215 retval->asoc = (struct sctp_association *)asoc;
1216 retval->resent = 0;
1217 retval->has_tsn = 0;
1218 retval->has_ssn = 0;
1219 retval->rtt_in_progress = 0;
1220 retval->sent_at = 0;
1221 retval->singleton = 1;
1222 retval->end_of_packet = 0;
1223 retval->ecn_ce_done = 0;
1224 retval->pdiscard = 0;
1225
1226 /* sctpimpguide-05.txt Section 2.8.2
1227 * M1) Each time a new DATA chunk is transmitted
1228 * set the 'TSN.Missing.Report' count for that TSN to 0. The
1229 * 'TSN.Missing.Report' count will be used to determine missing chunks
1230 * and when to fast retransmit.
1231 */
1232 retval->tsn_missing_report = 0;
1233 retval->tsn_gap_acked = 0;
c226ef9b 1234 retval->fast_retransmit = SCTP_CAN_FRTX;
1da177e4
LT		 1235
1236 /* If this is a fragmented message, track all fragments
1237 * of the message (for SEND_FAILED).
1238 */
1239 retval->msg = NULL;
1240
1241 /* Polish the bead hole. */
1242 INIT_LIST_HEAD(&retval->transmitted_list);
1243 INIT_LIST_HEAD(&retval->frag_list);
1244 SCTP_DBG_OBJCNT_INC(chunk);
1245 atomic_set(&retval->refcnt, 1);
1246
1247nodata:
1248 return retval;
1249}
1250
1251/* Set chunk->source and dest based on the IP header in chunk->skb. */
1252void sctp_init_addrs(struct sctp_chunk *chunk, union sctp_addr *src,
1253 union sctp_addr *dest)
1254{
f235fca3 1255 memcpy(&chunk->source, src, sizeof(union sctp_addr));
16b0a030 1256 memcpy(&chunk->dest, dest, sizeof(union sctp_addr));
1da177e4
LT		 1257}
1258
1259/* Extract the source address from a chunk. */
1260const union sctp_addr *sctp_source(const struct sctp_chunk *chunk)
1261{
1262 /* If we have a known transport, use that. */
1263 if (chunk->transport) {
6a1e5f33 1264 return &chunk->transport->ipaddr;
1da177e4
LT		 1265 } else {
1266 /* Otherwise, extract it from the IP header. */
6a1e5f33 1267 return &chunk->source;
1da177e4
LT		 1268 }
1269}
1270
1271/* Create a new chunk, setting the type and flags headers from the
1272 * arguments, reserving enough space for a 'paylen' byte payload.
1273 */
1274SCTP_STATIC
1275struct sctp_chunk *sctp_make_chunk(const struct sctp_association *asoc,
1276 __u8 type, __u8 flags, int paylen)
1277{
1278 struct sctp_chunk *retval;
1279 sctp_chunkhdr_t *chunk_hdr;
1280 struct sk_buff *skb;
1281 struct sock *sk;
1282
1283 /* No need to allocate LL here, as this is only a chunk. */
1284 skb = alloc_skb(WORD_ROUND(sizeof(sctp_chunkhdr_t) + paylen),
1285 GFP_ATOMIC);
1286 if (!skb)
1287 goto nodata;
1288
1289 /* Make room for the chunk header. */
1290 chunk_hdr = (sctp_chunkhdr_t *)skb_put(skb, sizeof(sctp_chunkhdr_t));
1291 chunk_hdr->type = type;
1292 chunk_hdr->flags = flags;
1293 chunk_hdr->length = htons(sizeof(sctp_chunkhdr_t));
1294
1295 sk = asoc ? asoc->base.sk : NULL;
1296 retval = sctp_chunkify(skb, asoc, sk);
1297 if (!retval) {
1298 kfree_skb(skb);
1299 goto nodata;
1300 }
1301
1302 retval->chunk_hdr = chunk_hdr;
1303 retval->chunk_end = ((__u8 *)chunk_hdr) + sizeof(struct sctp_chunkhdr);
1304
4cd57c80
VY		 1305 /* Determine if the chunk needs to be authenticated */
1306 if (sctp_auth_send_cid(type, asoc))
1307 retval->auth = 1;
1308
1da177e4
LT		 1309 /* Set the skb to the belonging sock for accounting. */
1310 skb->sk = sk;
1311
1312 return retval;
1313nodata:
1314 return NULL;
1315}
1316
1317
1318/* Release the memory occupied by a chunk. */
1319static void sctp_chunk_destroy(struct sctp_chunk *chunk)
1320{
a08de64d
VY		 1321 BUG_ON(!list_empty(&chunk->list));
1322 list_del_init(&chunk->transmitted_list);
1323
1da177e4
LT		 1324 /* Free the chunk skb data and the SCTP_chunk stub itself. */
1325 dev_kfree_skb(chunk->skb);
1326
1327 SCTP_DBG_OBJCNT_DEC(chunk);
1328 kmem_cache_free(sctp_chunk_cachep, chunk);
1329}
1330
1331/* Possibly, free the chunk. */
1332void sctp_chunk_free(struct sctp_chunk *chunk)
1333{
1da177e4
LT		 1334 /* Release our reference on the message tracker. */
1335 if (chunk->msg)
1336 sctp_datamsg_put(chunk->msg);
1337
1338 sctp_chunk_put(chunk);
1339}
1340
1341/* Grab a reference to the chunk. */
1342void sctp_chunk_hold(struct sctp_chunk *ch)
1343{
1344 atomic_inc(&ch->refcnt);
1345}
1346
1347/* Release a reference to the chunk. */
1348void sctp_chunk_put(struct sctp_chunk *ch)
1349{
1350 if (atomic_dec_and_test(&ch->refcnt))
1351 sctp_chunk_destroy(ch);
1352}
1353
1354/* Append bytes to the end of a chunk. Will panic if chunk is not big
1355 * enough.
1356 */
1357void *sctp_addto_chunk(struct sctp_chunk *chunk, int len, const void *data)
1358{
1359 void *target;
1360 void *padding;
1361 int chunklen = ntohs(chunk->chunk_hdr->length);
8d614ade 1362 int padlen = WORD_ROUND(chunklen) - chunklen;
1da177e4
LT		 1363
1364 padding = skb_put(chunk->skb, padlen);
1365 target = skb_put(chunk->skb, len);
1366
1367 memset(padding, 0, padlen);
1368 memcpy(target, data, len);
1369
1370 /* Adjust the chunk length field. */
1371 chunk->chunk_hdr->length = htons(chunklen + padlen + len);
27a884dc 1372 chunk->chunk_end = skb_tail_pointer(chunk->skb);
1da177e4
LT		 1373
1374 return target;
1375}
1376
1377/* Append bytes from user space to the end of a chunk. Will panic if
1378 * chunk is not big enough.
1379 * Returns a kernel err value.
1380 */
1381int sctp_user_addto_chunk(struct sctp_chunk *chunk, int off, int len,
1382 struct iovec *data)
1383{
1384 __u8 *target;
1385 int err = 0;
1386
1387 /* Make room in chunk for data. */
1388 target = skb_put(chunk->skb, len);
1389
1390 /* Copy data (whole iovec) into chunk */
1391 if ((err = memcpy_fromiovecend(target, data, off, len)))
1392 goto out;
1393
1394 /* Adjust the chunk length field. */
1395 chunk->chunk_hdr->length =
1396 htons(ntohs(chunk->chunk_hdr->length) + len);
27a884dc 1397 chunk->chunk_end = skb_tail_pointer(chunk->skb);
1da177e4
LT		 1398
1399out:
1400 return err;
1401}
1402
1403/* Helper function to assign a TSN if needed. This assumes that both
1404 * the data_hdr and association have already been assigned.
1405 */
1406void sctp_chunk_assign_ssn(struct sctp_chunk *chunk)
1407{
ab3e5e7b
VY		 1408 struct sctp_datamsg *msg;
1409 struct sctp_chunk *lchunk;
1410 struct sctp_stream *stream;
1da177e4
LT		 1411 __u16 ssn;
1412 __u16 sid;
1413
1414 if (chunk->has_ssn)
1415 return;
1416
ab3e5e7b
VY		 1417 /* All fragments will be on the same stream */
1418 sid = ntohs(chunk->subh.data_hdr->stream);
1419 stream = &chunk->asoc->ssnmap->out;
1da177e4 1420
ab3e5e7b
VY		 1421 /* Now assign the sequence number to the entire message.
1422 * All fragments must have the same stream sequence number.
1423 */
1424 msg = chunk->msg;
1425 list_for_each_entry(lchunk, &msg->chunks, frag_list) {
1426 if (lchunk->chunk_hdr->flags & SCTP_DATA_UNORDERED) {
1427 ssn = 0;
1428 } else {
1429 if (lchunk->chunk_hdr->flags & SCTP_DATA_LAST_FRAG)
1430 ssn = sctp_ssn_next(stream, sid);
1431 else
1432 ssn = sctp_ssn_peek(stream, sid);
1433 }
1434
1435 lchunk->subh.data_hdr->ssn = htons(ssn);
1436 lchunk->has_ssn = 1;
1437 }
1da177e4
LT		 1438}
1439
1440/* Helper function to assign a TSN if needed. This assumes that both
1441 * the data_hdr and association have already been assigned.
1442 */
1443void sctp_chunk_assign_tsn(struct sctp_chunk *chunk)
1444{
1445 if (!chunk->has_tsn) {
1446 /* This is the last possible instant to
1447 * assign a TSN.
1448 */
1449 chunk->subh.data_hdr->tsn =
1450 htonl(sctp_association_get_next_tsn(chunk->asoc));
1451 chunk->has_tsn = 1;
1452 }
1453}
1454
1455/* Create a CLOSED association to use with an incoming packet. */
1456struct sctp_association *sctp_make_temp_asoc(const struct sctp_endpoint *ep,
3182cd84 1457 struct sctp_chunk *chunk,
dd0fc66f 1458 gfp_t gfp)
1da177e4
LT		 1459{
1460 struct sctp_association *asoc;
1461 struct sk_buff *skb;
1462 sctp_scope_t scope;
1463 struct sctp_af *af;
1464
1465 /* Create the bare association. */
1466 scope = sctp_scope(sctp_source(chunk));
1467 asoc = sctp_association_new(ep, ep->base.sk, scope, gfp);
1468 if (!asoc)
1469 goto nodata;
1470 asoc->temp = 1;
1471 skb = chunk->skb;
1472 /* Create an entry for the source address of the packet. */
eddc9ec5 1473 af = sctp_get_af_specific(ipver2af(ip_hdr(skb)->version));
1da177e4
LT		 1474 if (unlikely(!af))
1475 goto fail;
d55c41b1 1476 af->from_skb(&asoc->c.peer_addr, skb, 1);
1da177e4
LT		 1477nodata:
1478 return asoc;
1479
1480fail:
1481 sctp_association_free(asoc);
1482 return NULL;
1483}
1484
1485/* Build a cookie representing asoc.
1486 * This INCLUDES the param header needed to put the cookie in the INIT ACK.
1487 */
1488static sctp_cookie_param_t *sctp_pack_cookie(const struct sctp_endpoint *ep,
1489 const struct sctp_association *asoc,
1490 const struct sctp_chunk *init_chunk,
1491 int *cookie_len,
1492 const __u8 *raw_addrs, int addrs_len)
1493{
1494 sctp_cookie_param_t *retval;
1495 struct sctp_signed_cookie *cookie;
1496 struct scatterlist sg;
1497 int headersize, bodysize;
1498 unsigned int keylen;
1499 char *key;
1500
9834a2bb
VY		 1501 /* Header size is static data prior to the actual cookie, including
1502 * any padding.
1503 */
d808ad9a
YH		 1504 headersize = sizeof(sctp_paramhdr_t) +
1505 (sizeof(struct sctp_signed_cookie) -
9834a2bb 1506 sizeof(struct sctp_cookie));
1da177e4
LT		 1507 bodysize = sizeof(struct sctp_cookie)
1508 + ntohs(init_chunk->chunk_hdr->length) + addrs_len;
1509
1510 /* Pad out the cookie to a multiple to make the signature
1511 * functions simpler to write.
1512 */
1513 if (bodysize % SCTP_COOKIE_MULTIPLE)
1514 bodysize += SCTP_COOKIE_MULTIPLE
1515 - (bodysize % SCTP_COOKIE_MULTIPLE);
1516 *cookie_len = headersize + bodysize;
1517
1da177e4
LT		 1518 /* Clear this memory since we are sending this data structure
1519 * out on the network.
1520 */
af997d8c
ACM		 1521 retval = kzalloc(*cookie_len, GFP_ATOMIC);
1522 if (!retval)
1523 goto nodata;
1524
1da177e4
LT		 1525 cookie = (struct sctp_signed_cookie *) retval->body;
1526
1527 /* Set up the parameter header. */
1528 retval->p.type = SCTP_PARAM_STATE_COOKIE;
1529 retval->p.length = htons(*cookie_len);
1530
1531 /* Copy the cookie part of the association itself. */
1532 cookie->c = asoc->c;
1533 /* Save the raw address list length in the cookie. */
1534 cookie->c.raw_addr_list_len = addrs_len;
1535
1536 /* Remember PR-SCTP capability. */
1537 cookie->c.prsctp_capable = asoc->peer.prsctp_capable;
1538
0f3fffd8
ISJ		 1539 /* Save adaptation indication in the cookie. */
1540 cookie->c.adaptation_ind = asoc->peer.adaptation_ind;
1da177e4
LT		 1541
1542 /* Set an expiration time for the cookie. */
1543 do_gettimeofday(&cookie->c.expiration);
1544 TIMEVAL_ADD(asoc->cookie_life, cookie->c.expiration);
1545
1546 /* Copy the peer's init packet. */
1547 memcpy(&cookie->c.peer_init[0], init_chunk->chunk_hdr,
1548 ntohs(init_chunk->chunk_hdr->length));
1549
1550 /* Copy the raw local address list of the association. */
1551 memcpy((__u8 *)&cookie->c.peer_init[0] +
1552 ntohs(init_chunk->chunk_hdr->length), raw_addrs, addrs_len);
1553
d808ad9a 1554 if (sctp_sk(ep->base.sk)->hmac) {
1b489e11
HX		 1555 struct hash_desc desc;
1556
1da177e4 1557 /* Sign the message. */
68e3f5dd 1558 sg_init_one(&sg, &cookie->c, bodysize);
1da177e4
LT		 1559 keylen = SCTP_SECRET_SIZE;
1560 key = (char *)ep->secret_key[ep->current_key];
d808ad9a
YH		 1561 desc.tfm = sctp_sk(ep->base.sk)->hmac;
1562 desc.flags = 0;
1da177e4 1563
1b489e11
HX		 1564 if (crypto_hash_setkey(desc.tfm, key, keylen) ||
1565 crypto_hash_digest(&desc, &sg, bodysize, cookie->signature))
1566 goto free_cookie;
1da177e4
LT		 1567 }
1568
1da177e4 1569 return retval;
1b489e11
HX		 1570
1571free_cookie:
1572 kfree(retval);
1573nodata:
1574 *cookie_len = 0;
1575 return NULL;
1da177e4
LT		 1576}
1577
1578/* Unpack the cookie from COOKIE ECHO chunk, recreating the association. */
1579struct sctp_association *sctp_unpack_cookie(
1580 const struct sctp_endpoint *ep,
1581 const struct sctp_association *asoc,
dd0fc66f 1582 struct sctp_chunk *chunk, gfp_t gfp,
1da177e4
LT		 1583 int *error, struct sctp_chunk **errp)
1584{
1585 struct sctp_association *retval = NULL;
1586 struct sctp_signed_cookie *cookie;
1587 struct sctp_cookie *bear_cookie;
1588 int headersize, bodysize, fixed_size;
313e7b4d 1589 __u8 *digest = ep->digest;
1da177e4
LT		 1590 struct scatterlist sg;
1591 unsigned int keylen, len;
1592 char *key;
1593 sctp_scope_t scope;
1594 struct sk_buff *skb = chunk->skb;
a61bbcf2 1595 struct timeval tv;
1b489e11 1596 struct hash_desc desc;
1da177e4 1597
9834a2bb
VY		 1598 /* Header size is static data prior to the actual cookie, including
1599 * any padding.
1600 */
1601 headersize = sizeof(sctp_chunkhdr_t) +
d808ad9a 1602 (sizeof(struct sctp_signed_cookie) -
9834a2bb 1603 sizeof(struct sctp_cookie));
1da177e4
LT		 1604 bodysize = ntohs(chunk->chunk_hdr->length) - headersize;
1605 fixed_size = headersize + sizeof(struct sctp_cookie);
1606
1607 /* Verify that the chunk looks like it even has a cookie.
1608 * There must be enough room for our cookie and our peer's
1609 * INIT chunk.
1610 */
1611 len = ntohs(chunk->chunk_hdr->length);
1612 if (len < fixed_size + sizeof(struct sctp_chunkhdr))
1613 goto malformed;
1614
1615 /* Verify that the cookie has been padded out. */
1616 if (bodysize % SCTP_COOKIE_MULTIPLE)
1617 goto malformed;
1618
1619 /* Process the cookie. */
1620 cookie = chunk->subh.cookie_hdr;
1621 bear_cookie = &cookie->c;
1622
1623 if (!sctp_sk(ep->base.sk)->hmac)
1624 goto no_hmac;
1625
1626 /* Check the signature. */
1627 keylen = SCTP_SECRET_SIZE;
68e3f5dd 1628 sg_init_one(&sg, bear_cookie, bodysize);
1da177e4 1629 key = (char *)ep->secret_key[ep->current_key];
1b489e11
HX		 1630 desc.tfm = sctp_sk(ep->base.sk)->hmac;
1631 desc.flags = 0;
1da177e4 1632
8ca84481 1633 memset(digest, 0x00, SCTP_SIGNATURE_SIZE);
1b489e11
HX		 1634 if (crypto_hash_setkey(desc.tfm, key, keylen) ||
1635 crypto_hash_digest(&desc, &sg, bodysize, digest)) {
1636 *error = -SCTP_IERROR_NOMEM;
1637 goto fail;
1638 }
1da177e4
LT		 1639
1640 if (memcmp(digest, cookie->signature, SCTP_SIGNATURE_SIZE)) {
1641 /* Try the previous key. */
1642 key = (char *)ep->secret_key[ep->last_key];
8ca84481 1643 memset(digest, 0x00, SCTP_SIGNATURE_SIZE);
1b489e11
HX		 1644 if (crypto_hash_setkey(desc.tfm, key, keylen) ||
1645 crypto_hash_digest(&desc, &sg, bodysize, digest)) {
1646 *error = -SCTP_IERROR_NOMEM;
1647 goto fail;
1648 }
1da177e4
LT		 1649
1650 if (memcmp(digest, cookie->signature, SCTP_SIGNATURE_SIZE)) {
1651 /* Yikes! Still bad signature! */
1652 *error = -SCTP_IERROR_BAD_SIG;
1653 goto fail;
1654 }
1655 }
1656
1657no_hmac:
1658 /* IG Section 2.35.2:
1659 * 3) Compare the port numbers and the verification tag contained
1660 * within the COOKIE ECHO chunk to the actual port numbers and the
1661 * verification tag within the SCTP common header of the received
1662 * packet. If these values do not match the packet MUST be silently
1663 * discarded,
1664 */
1665 if (ntohl(chunk->sctp_hdr->vtag) != bear_cookie->my_vtag) {
1666 *error = -SCTP_IERROR_BAD_TAG;
1667 goto fail;
1668 }
1669
9b1dfad0 1670 if (chunk->sctp_hdr->source != bear_cookie->peer_addr.v4.sin_port ||
1da177e4
LT		 1671 ntohs(chunk->sctp_hdr->dest) != bear_cookie->my_port) {
1672 *error = -SCTP_IERROR_BAD_PORTS;
1673 goto fail;
1674 }
1675
1676 /* Check to see if the cookie is stale. If there is already
1677 * an association, there is no need to check cookie's expiration
1678 * for init collision case of lost COOKIE ACK.
f236218b
VY		 1679 * If skb has been timestamped, then use the stamp, otherwise
1680 * use current time. This introduces a small possibility that
1681 * that a cookie may be considered expired, but his would only slow
1682 * down the new association establishment instead of every packet.
1da177e4 1683 */
f236218b
VY		 1684 if (sock_flag(ep->base.sk, SOCK_TIMESTAMP))
1685 skb_get_timestamp(skb, &tv);
1686 else
1687 do_gettimeofday(&tv);
1688
a61bbcf2 1689 if (!asoc && tv_lt(bear_cookie->expiration, tv)) {
1da177e4
LT		 1690 /*
1691 * Section 3.3.10.3 Stale Cookie Error (3)
1692 *
1693 * Cause of error
1694 * ---------------
1695 * Stale Cookie Error: Indicates the receipt of a valid State
1696 * Cookie that has expired.
1697 */
1698 len = ntohs(chunk->chunk_hdr->length);
1699 *errp = sctp_make_op_error_space(asoc, chunk, len);
1700 if (*errp) {
a61bbcf2 1701 suseconds_t usecs = (tv.tv_sec -
1da177e4 1702 bear_cookie->expiration.tv_sec) * 1000000L +
a61bbcf2 1703 tv.tv_usec - bear_cookie->expiration.tv_usec;
34bcca28 1704 __be32 n = htonl(usecs);
1da177e4 1705
1da177e4 1706 sctp_init_cause(*errp, SCTP_ERROR_STALE_COOKIE,
00f1c2df
WY		 1707 sizeof(n));
1708 sctp_addto_chunk(*errp, sizeof(n), &n);
1da177e4
LT		 1709 *error = -SCTP_IERROR_STALE_COOKIE;
1710 } else
1711 *error = -SCTP_IERROR_NOMEM;
1712
1713 goto fail;
1714 }
1715
1716 /* Make a new base association. */
1717 scope = sctp_scope(sctp_source(chunk));
1718 retval = sctp_association_new(ep, ep->base.sk, scope, gfp);
1719 if (!retval) {
1720 *error = -SCTP_IERROR_NOMEM;
1721 goto fail;
1722 }
1723
1724 /* Set up our peer's port number. */
1725 retval->peer.port = ntohs(chunk->sctp_hdr->source);
1726
1727 /* Populate the association from the cookie. */
1728 memcpy(&retval->c, bear_cookie, sizeof(*bear_cookie));
1729
1730 if (sctp_assoc_set_bind_addr_from_cookie(retval, bear_cookie,
1731 GFP_ATOMIC) < 0) {
1732 *error = -SCTP_IERROR_NOMEM;
1733 goto fail;
1734 }
1735
1736 /* Also, add the destination address. */
1737 if (list_empty(&retval->base.bind_addr.address_list)) {
f57d96b2
VY		 1738 sctp_add_bind_addr(&retval->base.bind_addr, &chunk->dest,
1739 SCTP_ADDR_SRC, GFP_ATOMIC);
1da177e4
LT		 1740 }
1741
1742 retval->next_tsn = retval->c.initial_tsn;
1743 retval->ctsn_ack_point = retval->next_tsn - 1;
1744 retval->addip_serial = retval->c.initial_tsn;
1745 retval->adv_peer_ack_point = retval->ctsn_ack_point;
1746 retval->peer.prsctp_capable = retval->c.prsctp_capable;
0f3fffd8 1747 retval->peer.adaptation_ind = retval->c.adaptation_ind;
1da177e4
LT		 1748
1749 /* The INIT stuff will be done by the side effects. */
1750 return retval;
1751
1752fail:
1753 if (retval)
1754 sctp_association_free(retval);
1755
1756 return NULL;
1757
1758malformed:
1759 /* Yikes! The packet is either corrupt or deliberately
1760 * malformed.
1761 */
1762 *error = -SCTP_IERROR_MALFORMED;
1763 goto fail;
1764}
1765
1766/********************************************************************
1767 * 3rd Level Abstractions
1768 ********************************************************************/
1769
1770struct __sctp_missing {
9f81bcd9
AV		 1771 __be32 num_missing;
1772 __be16 type;
1da177e4
LT		 1773} __attribute__((packed));
1774
1775/*
1776 * Report a missing mandatory parameter.
1777 */
1778static int sctp_process_missing_param(const struct sctp_association *asoc,
1779 sctp_param_t paramtype,
1780 struct sctp_chunk *chunk,
1781 struct sctp_chunk **errp)
1782{
1783 struct __sctp_missing report;
1784 __u16 len;
1785
1786 len = WORD_ROUND(sizeof(report));
1787
1788 /* Make an ERROR chunk, preparing enough room for
1789 * returning multiple unknown parameters.
1790 */
1791 if (!*errp)
1792 *errp = sctp_make_op_error_space(asoc, chunk, len);
1793
1794 if (*errp) {
1795 report.num_missing = htonl(1);
1796 report.type = paramtype;
ebdfcad4 1797 sctp_init_cause(*errp, SCTP_ERROR_MISS_PARAM,
00f1c2df
WY		 1798 sizeof(report));
1799 sctp_addto_chunk(*errp, sizeof(report), &report);
1da177e4
LT		 1800 }
1801
1802 /* Stop processing this chunk. */
1803 return 0;
1804}
1805
1806/* Report an Invalid Mandatory Parameter. */
1807static int sctp_process_inv_mandatory(const struct sctp_association *asoc,
1808 struct sctp_chunk *chunk,
1809 struct sctp_chunk **errp)
1810{
1811 /* Invalid Mandatory Parameter Error has no payload. */
1812
1813 if (!*errp)
1814 *errp = sctp_make_op_error_space(asoc, chunk, 0);
1815
1816 if (*errp)
00f1c2df 1817 sctp_init_cause(*errp, SCTP_ERROR_INV_PARAM, 0);
1da177e4
LT		 1818
1819 /* Stop processing this chunk. */
1820 return 0;
1821}
1822
1823static int sctp_process_inv_paramlength(const struct sctp_association *asoc,
1824 struct sctp_paramhdr *param,
1825 const struct sctp_chunk *chunk,
1826 struct sctp_chunk **errp)
1827{
7ab90804
VY		 1828 /* This is a fatal error. Any accumulated non-fatal errors are
1829 * not reported.
1830 */
1831 if (*errp)
1832 sctp_chunk_free(*errp);
1833
1da177e4 1834 /* Create an error chunk and fill it in with our payload. */
ba016670 1835 *errp = sctp_make_violation_paramlen(asoc, chunk, param);
1da177e4
LT		 1836
1837 return 0;
1838}
1839
1840
1841/* Do not attempt to handle the HOST_NAME parm. However, do
1842 * send back an indicator to the peer.
1843 */
1844static int sctp_process_hn_param(const struct sctp_association *asoc,
1845 union sctp_params param,
1846 struct sctp_chunk *chunk,
1847 struct sctp_chunk **errp)
1848{
1849 __u16 len = ntohs(param.p->length);
1850
7ab90804
VY		 1851 /* Processing of the HOST_NAME parameter will generate an
1852 * ABORT. If we've accumulated any non-fatal errors, they
1853 * would be unrecognized parameters and we should not include
1854 * them in the ABORT.
1855 */
1856 if (*errp)
1857 sctp_chunk_free(*errp);
1858
1859 *errp = sctp_make_op_error_space(asoc, chunk, len);
1da177e4 1860
00f1c2df
WY		 1861 if (*errp) {
1862 sctp_init_cause(*errp, SCTP_ERROR_DNS_FAILED, len);
1863 sctp_addto_chunk(*errp, len, param.v);
1864 }
1da177e4
LT		 1865
1866 /* Stop processing this chunk. */
1867 return 0;
1868}
1869
d6701191
VY		 1870static int sctp_verify_ext_param(union sctp_params param)
1871{
1872 __u16 num_ext = ntohs(param.p->length) - sizeof(sctp_paramhdr_t);
1873 int have_auth = 0;
1874 int have_asconf = 0;
1875 int i;
1876
1877 for (i = 0; i < num_ext; i++) {
1878 switch (param.ext->chunks[i]) {
1879 case SCTP_CID_AUTH:
1880 have_auth = 1;
1881 break;
1882 case SCTP_CID_ASCONF:
1883 case SCTP_CID_ASCONF_ACK:
1884 have_asconf = 1;
1885 break;
1886 }
1887 }
1888
1889 /* ADD-IP Security: The draft requires us to ABORT or ignore the
1890 * INIT/INIT-ACK if ADD-IP is listed, but AUTH is not. Do this
1891 * only if ADD-IP is turned on and we are not backward-compatible
1892 * mode.
1893 */
1894 if (sctp_addip_noauth)
1895 return 1;
1896
1897 if (sctp_addip_enable && !have_auth && have_asconf)
1898 return 0;
1899
1900 return 1;
1901}
1902
131a47e3
VY		 1903static void sctp_process_ext_param(struct sctp_association *asoc,
1904 union sctp_params param)
1905{
1906 __u16 num_ext = ntohs(param.p->length) - sizeof(sctp_paramhdr_t);
1907 int i;
1908
1909 for (i = 0; i < num_ext; i++) {
1910 switch (param.ext->chunks[i]) {
1911 case SCTP_CID_FWD_TSN:
1912 if (sctp_prsctp_enable &&
1913 !asoc->peer.prsctp_capable)
1914 asoc->peer.prsctp_capable = 1;
1915 break;
730fc3d0
VY		 1916 case SCTP_CID_AUTH:
1917 /* if the peer reports AUTH, assume that he
1918 * supports AUTH.
1919 */
0ef46e28
VY		 1920 if (sctp_auth_enable)
1921 asoc->peer.auth_capable = 1;
730fc3d0 1922 break;
131a47e3
VY		 1923 case SCTP_CID_ASCONF:
1924 case SCTP_CID_ASCONF_ACK:
0ef46e28
VY		 1925 if (sctp_addip_enable)
1926 asoc->peer.asconf_capable = 1;
6b2f9cb6 1927 break;
131a47e3
VY		 1928 default:
1929 break;
1930 }
1931 }
1932}
1933
1da177e4
LT		 1934/* RFC 3.2.1 & the Implementers Guide 2.2.
1935 *
1936 * The Parameter Types are encoded such that the
1937 * highest-order two bits specify the action that must be
1938 * taken if the processing endpoint does not recognize the
1939 * Parameter Type.
1940 *
7ab90804
VY		 1941 * 00 - Stop processing this parameter; do not process any further
1942 * parameters within this chunk
1da177e4 1943 *
7ab90804
VY		 1944 * 01 - Stop processing this parameter, do not process any further
1945 * parameters within this chunk, and report the unrecognized
1946 * parameter in an 'Unrecognized Parameter' ERROR chunk.
1da177e4
LT		 1947 *
1948 * 10 - Skip this parameter and continue processing.
1949 *
1950 * 11 - Skip this parameter and continue processing but
1951 * report the unrecognized parameter in an
7ab90804 1952 * 'Unrecognized Parameter' ERROR chunk.
1da177e4
LT		 1953 *
1954 * Return value:
7ab90804
VY		 1955 * SCTP_IERROR_NO_ERROR - continue with the chunk
1956 * SCTP_IERROR_ERROR - stop and report an error.
1957 * SCTP_IERROR_NOMEME - out of memory.
1da177e4 1958 */
7ab90804
VY		 1959static sctp_ierror_t sctp_process_unk_param(const struct sctp_association *asoc,
1960 union sctp_params param,
1961 struct sctp_chunk *chunk,
1962 struct sctp_chunk **errp)
1da177e4 1963{
7ab90804 1964 int retval = SCTP_IERROR_NO_ERROR;
1da177e4
LT		 1965
1966 switch (param.p->type & SCTP_PARAM_ACTION_MASK) {
1967 case SCTP_PARAM_ACTION_DISCARD:
7ab90804 1968 retval = SCTP_IERROR_ERROR;
1da177e4
LT		 1969 break;
1970 case SCTP_PARAM_ACTION_SKIP:
1971 break;
7ab90804
VY		 1972 case SCTP_PARAM_ACTION_DISCARD_ERR:
1973 retval = SCTP_IERROR_ERROR;
1974 /* Fall through */
1da177e4
LT		 1975 case SCTP_PARAM_ACTION_SKIP_ERR:
1976 /* Make an ERROR chunk, preparing enough room for
1977 * returning multiple unknown parameters.
1978 */
1979 if (NULL == *errp)
1980 *errp = sctp_make_op_error_space(asoc, chunk,
1981 ntohs(chunk->chunk_hdr->length));
1982
1983 if (*errp) {
1984 sctp_init_cause(*errp, SCTP_ERROR_UNKNOWN_PARAM,
1da177e4 1985 WORD_ROUND(ntohs(param.p->length)));
00f1c2df
WY		 1986 sctp_addto_chunk(*errp,
1987 WORD_ROUND(ntohs(param.p->length)),
1988 param.v);
1da177e4
LT		 1989 } else {
1990 /* If there is no memory for generating the ERROR
1991 * report as specified, an ABORT will be triggered
1992 * to the peer and the association won't be
1993 * established.
1994 */
7ab90804 1995 retval = SCTP_IERROR_NOMEM;
1da177e4 1996 }
1da177e4
LT		 1997 break;
1998 default:
1999 break;
2000 }
2001
2002 return retval;
2003}
2004
7ab90804 2005/* Verify variable length parameters
1da177e4 2006 * Return values:
7ab90804
VY		 2007 * SCTP_IERROR_ABORT - trigger an ABORT
2008 * SCTP_IERROR_NOMEM - out of memory (abort)
2009 * SCTP_IERROR_ERROR - stop processing, trigger an ERROR
2010 * SCTP_IERROR_NO_ERROR - continue with the chunk
1da177e4 2011 */
7ab90804
VY		 2012static sctp_ierror_t sctp_verify_param(const struct sctp_association *asoc,
2013 union sctp_params param,
2014 sctp_cid_t cid,
2015 struct sctp_chunk *chunk,
2016 struct sctp_chunk **err_chunk)
1da177e4 2017{
72da7b38 2018 struct sctp_hmac_algo_param *hmacs;
7ab90804 2019 int retval = SCTP_IERROR_NO_ERROR;
72da7b38
WY		 2020 __u16 n_elt, id = 0;
2021 int i;
1da177e4
LT		 2022
2023 /* FIXME - This routine is not looking at each parameter per the
2024 * chunk type, i.e., unrecognized parameters should be further
2025 * identified based on the chunk id.
2026 */
2027
2028 switch (param.p->type) {
2029 case SCTP_PARAM_IPV4_ADDRESS:
2030 case SCTP_PARAM_IPV6_ADDRESS:
2031 case SCTP_PARAM_COOKIE_PRESERVATIVE:
2032 case SCTP_PARAM_SUPPORTED_ADDRESS_TYPES:
2033 case SCTP_PARAM_STATE_COOKIE:
2034 case SCTP_PARAM_HEARTBEAT_INFO:
2035 case SCTP_PARAM_UNRECOGNIZED_PARAMETERS:
2036 case SCTP_PARAM_ECN_CAPABLE:
0f3fffd8 2037 case SCTP_PARAM_ADAPTATION_LAYER_IND:
d6701191
VY		 2038 break;
2039
131a47e3 2040 case SCTP_PARAM_SUPPORTED_EXT:
d6701191
VY		 2041 if (!sctp_verify_ext_param(param))
2042 return SCTP_IERROR_ABORT;
1da177e4
LT		 2043 break;
2044
d6de3097
VY		 2045 case SCTP_PARAM_SET_PRIMARY:
2046 if (sctp_addip_enable)
2047 break;
2048 goto fallthrough;
2049
1da177e4
LT		 2050 case SCTP_PARAM_HOST_NAME_ADDRESS:
2051 /* Tell the peer, we won't support this param. */
7ab90804
VY		 2052 sctp_process_hn_param(asoc, param, chunk, err_chunk);
2053 retval = SCTP_IERROR_ABORT;
2054 break;
131a47e3 2055
1da177e4
LT		 2056 case SCTP_PARAM_FWD_TSN_SUPPORT:
2057 if (sctp_prsctp_enable)
2058 break;
730fc3d0
VY		 2059 goto fallthrough;
2060
2061 case SCTP_PARAM_RANDOM:
2062 if (!sctp_auth_enable)
2063 goto fallthrough;
2064
2065 /* SCTP-AUTH: Secion 6.1
2066 * If the random number is not 32 byte long the association
2067 * MUST be aborted. The ABORT chunk SHOULD contain the error
2068 * cause 'Protocol Violation'.
2069 */
2070 if (SCTP_AUTH_RANDOM_LENGTH !=
7ab90804
VY		 2071 ntohs(param.p->length) - sizeof(sctp_paramhdr_t)) {
2072 sctp_process_inv_paramlength(asoc, param.p,
730fc3d0 2073 chunk, err_chunk);
7ab90804
VY		 2074 retval = SCTP_IERROR_ABORT;
2075 }
730fc3d0
VY		 2076 break;
2077
2078 case SCTP_PARAM_CHUNKS:
2079 if (!sctp_auth_enable)
2080 goto fallthrough;
2081
2082 /* SCTP-AUTH: Section 3.2
2083 * The CHUNKS parameter MUST be included once in the INIT or
2084 * INIT-ACK chunk if the sender wants to receive authenticated
2085 * chunks. Its maximum length is 260 bytes.
2086 */
7ab90804
VY		 2087 if (260 < ntohs(param.p->length)) {
2088 sctp_process_inv_paramlength(asoc, param.p,
2089 chunk, err_chunk);
2090 retval = SCTP_IERROR_ABORT;
2091 }
730fc3d0
VY		 2092 break;
2093
2094 case SCTP_PARAM_HMAC_ALGO:
72da7b38
WY		 2095 if (!sctp_auth_enable)
2096 goto fallthrough;
2097
2098 hmacs = (struct sctp_hmac_algo_param *)param.p;
2099 n_elt = (ntohs(param.p->length) - sizeof(sctp_paramhdr_t)) >> 1;
2100
2101 /* SCTP-AUTH: Section 6.1
2102 * The HMAC algorithm based on SHA-1 MUST be supported and
2103 * included in the HMAC-ALGO parameter.
2104 */
2105 for (i = 0; i < n_elt; i++) {
2106 id = ntohs(hmacs->hmac_ids[i]);
2107
2108 if (id == SCTP_AUTH_HMAC_ID_SHA1)
2109 break;
2110 }
2111
2112 if (id != SCTP_AUTH_HMAC_ID_SHA1) {
2113 sctp_process_inv_paramlength(asoc, param.p, chunk,
2114 err_chunk);
2115 retval = SCTP_IERROR_ABORT;
2116 }
2117 break;
730fc3d0 2118fallthrough:
1da177e4
LT		 2119 default:
2120 SCTP_DEBUG_PRINTK("Unrecognized param: %d for chunk %d.\n",
2121 ntohs(param.p->type), cid);
7ab90804 2122 retval = sctp_process_unk_param(asoc, param, chunk, err_chunk);
1da177e4
LT		 2123 break;
2124 }
2125 return retval;
2126}
2127
2128/* Verify the INIT packet before we process it. */
2129int sctp_verify_init(const struct sctp_association *asoc,
2130 sctp_cid_t cid,
2131 sctp_init_chunk_t *peer_init,
2132 struct sctp_chunk *chunk,
2133 struct sctp_chunk **errp)
2134{
2135 union sctp_params param;
2136 int has_cookie = 0;
7ab90804 2137 int result;
1da177e4
LT		 2138
2139 /* Verify stream values are non-zero. */
2140 if ((0 == peer_init->init_hdr.num_outbound_streams) ||
d023f629
VY		 2141 (0 == peer_init->init_hdr.num_inbound_streams) ||
2142 (0 == peer_init->init_hdr.init_tag) ||
2143 (SCTP_DEFAULT_MINWINDOW > ntohl(peer_init->init_hdr.a_rwnd))) {
1da177e4 2144
7ab90804 2145 return sctp_process_inv_mandatory(asoc, chunk, errp);
1da177e4
LT		 2146 }
2147
2148 /* Check for missing mandatory parameters. */
2149 sctp_walk_params(param, peer_init, init_hdr.params) {
2150
2151 if (SCTP_PARAM_STATE_COOKIE == param.p->type)
2152 has_cookie = 1;
2153
2154 } /* for (loop through all parameters) */
2155
2156 /* There is a possibility that a parameter length was bad and
2157 * in that case we would have stoped walking the parameters.
2158 * The current param.p would point at the bad one.
2159 * Current consensus on the mailing list is to generate a PROTOCOL
2160 * VIOLATION error. We build the ERROR chunk here and let the normal
2161 * error handling code build and send the packet.
2162 */
7ab90804
VY		 2163 if (param.v != (void*)chunk->chunk_end)
2164 return sctp_process_inv_paramlength(asoc, param.p, chunk, errp);
1da177e4
LT		 2165
2166 /* The only missing mandatory param possible today is
2167 * the state cookie for an INIT-ACK chunk.
2168 */
7ab90804
VY		 2169 if ((SCTP_CID_INIT_ACK == cid) && !has_cookie)
2170 return sctp_process_missing_param(asoc, SCTP_PARAM_STATE_COOKIE,
2171 chunk, errp);
1da177e4 2172
7ab90804 2173 /* Verify all the variable length parameters */
1da177e4
LT		 2174 sctp_walk_params(param, peer_init, init_hdr.params) {
2175
7ab90804
VY		 2176 result = sctp_verify_param(asoc, param, cid, chunk, errp);
2177 switch (result) {
2178 case SCTP_IERROR_ABORT:
2179 case SCTP_IERROR_NOMEM:
1da177e4 2180 return 0;
7ab90804 2181 case SCTP_IERROR_ERROR:
1da177e4 2182 return 1;
7ab90804
VY		 2183 case SCTP_IERROR_NO_ERROR:
2184 default:
2185 break;
1da177e4
LT		 2186 }
2187
2188 } /* for (loop through all parameters) */
2189
2190 return 1;
2191}
2192
2193/* Unpack the parameters in an INIT packet into an association.
2194 * Returns 0 on failure, else success.
2195 * FIXME: This is an association method.
2196 */
2197int sctp_process_init(struct sctp_association *asoc, sctp_cid_t cid,
2198 const union sctp_addr *peer_addr,
dd0fc66f 2199 sctp_init_chunk_t *peer_init, gfp_t gfp)
1da177e4
LT		 2200{
2201 union sctp_params param;
2202 struct sctp_transport *transport;
2203 struct list_head *pos, *temp;
2204 char *cookie;
2205
2206 /* We must include the address that the INIT packet came from.
2207 * This is the only address that matters for an INIT packet.
2208 * When processing a COOKIE ECHO, we retrieve the from address
2209 * of the INIT from the cookie.
2210 */
2211
2212 /* This implementation defaults to making the first transport
2213 * added as the primary transport. The source address seems to
2214 * be a a better choice than any of the embedded addresses.
2215 */
4bdf4b5f 2216 if (peer_addr) {
6a1e5f33 2217 if(!sctp_assoc_add_peer(asoc, peer_addr, gfp, SCTP_ACTIVE))
1da177e4 2218 goto nomem;
4bdf4b5f 2219 }
1da177e4
LT		 2220
2221 /* Process the initialization parameters. */
1da177e4
LT		 2222 sctp_walk_params(param, peer_init, init_hdr.params) {
2223
2224 if (!sctp_process_param(asoc, param, peer_addr, gfp))
d808ad9a 2225 goto clean_up;
1da177e4
LT		 2226 }
2227
730fc3d0
VY		 2228 /* AUTH: After processing the parameters, make sure that we
2229 * have all the required info to potentially do authentications.
2230 */
2231 if (asoc->peer.auth_capable && (!asoc->peer.peer_random ||
2232 !asoc->peer.peer_hmacs))
2233 asoc->peer.auth_capable = 0;
2234
d6701191
VY		 2235 /* In a non-backward compatible mode, if the peer claims
2236 * support for ADD-IP but not AUTH, the ADD-IP spec states
2237 * that we MUST ABORT the association. Section 6. The section
2238 * also give us an option to silently ignore the packet, which
2239 * is what we'll do here.
6b2f9cb6 2240 */
73d9c4fd
VY		 2241 if (!sctp_addip_noauth &&
2242 (asoc->peer.asconf_capable && !asoc->peer.auth_capable)) {
6b2f9cb6
VY		 2243 asoc->peer.addip_disabled_mask |= (SCTP_PARAM_ADD_IP |
2244 SCTP_PARAM_DEL_IP |
2245 SCTP_PARAM_SET_PRIMARY);
88799fe5 2246 asoc->peer.asconf_capable = 0;
d6701191 2247 goto clean_up;
6b2f9cb6
VY		 2248 }
2249
3f7a87d2
FF		 2250 /* Walk list of transports, removing transports in the UNKNOWN state. */
2251 list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
2252 transport = list_entry(pos, struct sctp_transport, transports);
2253 if (transport->state == SCTP_UNKNOWN) {
2254 sctp_assoc_rm_peer(asoc, transport);
2255 }
2256 }
2257
1da177e4
LT		 2258 /* The fixed INIT headers are always in network byte
2259 * order.
2260 */
2261 asoc->peer.i.init_tag =
2262 ntohl(peer_init->init_hdr.init_tag);
2263 asoc->peer.i.a_rwnd =
2264 ntohl(peer_init->init_hdr.a_rwnd);
2265 asoc->peer.i.num_outbound_streams =
2266 ntohs(peer_init->init_hdr.num_outbound_streams);
2267 asoc->peer.i.num_inbound_streams =
2268 ntohs(peer_init->init_hdr.num_inbound_streams);
2269 asoc->peer.i.initial_tsn =
2270 ntohl(peer_init->init_hdr.initial_tsn);
2271
2272 /* Apply the upper bounds for output streams based on peer's
2273 * number of inbound streams.
2274 */
2275 if (asoc->c.sinit_num_ostreams >
2276 ntohs(peer_init->init_hdr.num_inbound_streams)) {
2277 asoc->c.sinit_num_ostreams =
2278 ntohs(peer_init->init_hdr.num_inbound_streams);
2279 }
2280
2281 if (asoc->c.sinit_max_instreams >
2282 ntohs(peer_init->init_hdr.num_outbound_streams)) {
2283 asoc->c.sinit_max_instreams =
2284 ntohs(peer_init->init_hdr.num_outbound_streams);
2285 }
2286
2287 /* Copy Initiation tag from INIT to VT_peer in cookie. */
2288 asoc->c.peer_vtag = asoc->peer.i.init_tag;
2289
2290 /* Peer Rwnd : Current calculated value of the peer's rwnd. */
2291 asoc->peer.rwnd = asoc->peer.i.a_rwnd;
2292
2293 /* Copy cookie in case we need to resend COOKIE-ECHO. */
2294 cookie = asoc->peer.cookie;
2295 if (cookie) {
af997d8c 2296 asoc->peer.cookie = kmemdup(cookie, asoc->peer.cookie_len, gfp);
1da177e4
LT		 2297 if (!asoc->peer.cookie)
2298 goto clean_up;
1da177e4
LT		 2299 }
2300
2301 /* RFC 2960 7.2.1 The initial value of ssthresh MAY be arbitrarily
2302 * high (for example, implementations MAY use the size of the receiver
2303 * advertised window).
2304 */
9dbc15f0
RD		 2305 list_for_each_entry(transport, &asoc->peer.transport_addr_list,
2306 transports) {
1da177e4
LT		 2307 transport->ssthresh = asoc->peer.i.a_rwnd;
2308 }
2309
2310 /* Set up the TSN tracking pieces. */
8e1ee18c
VY		 2311 if (!sctp_tsnmap_init(&asoc->peer.tsn_map, SCTP_TSN_MAP_INITIAL,
2312 asoc->peer.i.initial_tsn, gfp))
2313 goto clean_up;
1da177e4
LT		 2314
2315 /* RFC 2960 6.5 Stream Identifier and Stream Sequence Number
2316 *
2317 * The stream sequence number in all the streams shall start
2318 * from 0 when the association is established. Also, when the
2319 * stream sequence number reaches the value 65535 the next
2320 * stream sequence number shall be set to 0.
2321 */
2322
3f7a87d2 2323 /* Allocate storage for the negotiated streams if it is not a temporary
d808ad9a 2324 * association.
1da177e4
LT		 2325 */
2326 if (!asoc->temp) {
1da177e4
LT		 2327 int error;
2328
2329 asoc->ssnmap = sctp_ssnmap_new(asoc->c.sinit_max_instreams,
2330 asoc->c.sinit_num_ostreams, gfp);
2331 if (!asoc->ssnmap)
2332 goto clean_up;
2333
07d93967
VY		 2334 error = sctp_assoc_set_id(asoc, gfp);
2335 if (error)
1da177e4 2336 goto clean_up;
1da177e4
LT		 2337 }
2338
2339 /* ADDIP Section 4.1 ASCONF Chunk Procedures
2340 *
2341 * When an endpoint has an ASCONF signaled change to be sent to the
2342 * remote endpoint it should do the following:
2343 * ...
2344 * A2) A serial number should be assigned to the Chunk. The serial
2345 * number should be a monotonically increasing number. All serial
2346 * numbers are defined to be initialized at the start of the
2347 * association to the same value as the Initial TSN.
2348 */
2349 asoc->peer.addip_serial = asoc->peer.i.initial_tsn - 1;
2350 return 1;
2351
2352clean_up:
2353 /* Release the transport structures. */
2354 list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
2355 transport = list_entry(pos, struct sctp_transport, transports);
add52379
VY		 2356 if (transport->state != SCTP_ACTIVE)
2357 sctp_assoc_rm_peer(asoc, transport);
1da177e4 2358 }
3f7a87d2 2359
1da177e4
LT		 2360nomem:
2361 return 0;
2362}
2363
2364
2365/* Update asoc with the option described in param.
2366 *
2367 * RFC2960 3.3.2.1 Optional/Variable Length Parameters in INIT
2368 *
2369 * asoc is the association to update.
2370 * param is the variable length parameter to use for update.
2371 * cid tells us if this is an INIT, INIT ACK or COOKIE ECHO.
2372 * If the current packet is an INIT we want to minimize the amount of
2373 * work we do. In particular, we should not build transport
2374 * structures for the addresses.
2375 */
2376static int sctp_process_param(struct sctp_association *asoc,
2377 union sctp_params param,
2378 const union sctp_addr *peer_addr,
dd0fc66f 2379 gfp_t gfp)
1da177e4
LT		 2380{
2381 union sctp_addr addr;
2382 int i;
2383 __u16 sat;
2384 int retval = 1;
2385 sctp_scope_t scope;
2386 time_t stale;
2387 struct sctp_af *af;
d6de3097
VY		 2388 union sctp_addr_param *addr_param;
2389 struct sctp_transport *t;
1da177e4
LT		 2390
2391 /* We maintain all INIT parameters in network byte order all the
2392 * time. This allows us to not worry about whether the parameters
2393 * came from a fresh INIT, and INIT ACK, or were stored in a cookie.
2394 */
2395 switch (param.p->type) {
2396 case SCTP_PARAM_IPV6_ADDRESS:
2397 if (PF_INET6 != asoc->base.sk->sk_family)
2398 break;
7dab83de
VY		 2399 goto do_addr_param;
2400
1da177e4 2401 case SCTP_PARAM_IPV4_ADDRESS:
7dab83de
VY		 2402 /* v4 addresses are not allowed on v6-only socket */
2403 if (ipv6_only_sock(asoc->base.sk))
2404 break;
2405do_addr_param:
1da177e4 2406 af = sctp_get_af_specific(param_type2af(param.p->type));
dd86d136 2407 af->from_addr_param(&addr, param.addr, htons(asoc->peer.port), 0);
1da177e4 2408 scope = sctp_scope(peer_addr);
dd86d136
AV		 2409 if (sctp_in_scope(&addr, scope))
2410 if (!sctp_assoc_add_peer(asoc, &addr, gfp, SCTP_UNCONFIRMED))
1da177e4
LT		 2411 return 0;
2412 break;
2413
2414 case SCTP_PARAM_COOKIE_PRESERVATIVE:
2415 if (!sctp_cookie_preserve_enable)
2416 break;
2417
2418 stale = ntohl(param.life->lifespan_increment);
2419
2420 /* Suggested Cookie Life span increment's unit is msec,
2421 * (1/1000sec).
2422 */
2423 asoc->cookie_life.tv_sec += stale / 1000;
2424 asoc->cookie_life.tv_usec += (stale % 1000) * 1000;
2425 break;
2426
2427 case SCTP_PARAM_HOST_NAME_ADDRESS:
2428 SCTP_DEBUG_PRINTK("unimplemented SCTP_HOST_NAME_ADDRESS\n");
2429 break;
2430
2431 case SCTP_PARAM_SUPPORTED_ADDRESS_TYPES:
2432 /* Turn off the default values first so we'll know which
2433 * ones are really set by the peer.
2434 */
2435 asoc->peer.ipv4_address = 0;
2436 asoc->peer.ipv6_address = 0;
2437
140ee960
GJ		 2438 /* Assume that peer supports the address family
2439 * by which it sends a packet.
2440 */
2441 if (peer_addr->sa.sa_family == AF_INET6)
2442 asoc->peer.ipv6_address = 1;
2443 else if (peer_addr->sa.sa_family == AF_INET)
2444 asoc->peer.ipv4_address = 1;
2445
1da177e4
LT		 2446 /* Cycle through address types; avoid divide by 0. */
2447 sat = ntohs(param.p->length) - sizeof(sctp_paramhdr_t);
2448 if (sat)
2449 sat /= sizeof(__u16);
2450
2451 for (i = 0; i < sat; ++i) {
2452 switch (param.sat->types[i]) {
2453 case SCTP_PARAM_IPV4_ADDRESS:
2454 asoc->peer.ipv4_address = 1;
2455 break;
2456
2457 case SCTP_PARAM_IPV6_ADDRESS:
6e40a915
WY		 2458 if (PF_INET6 == asoc->base.sk->sk_family)
2459 asoc->peer.ipv6_address = 1;
1da177e4
LT		 2460 break;
2461
2462 case SCTP_PARAM_HOST_NAME_ADDRESS:
2463 asoc->peer.hostname_address = 1;
2464 break;
2465
2466 default: /* Just ignore anything else. */
2467 break;
3ff50b79 2468 }
1da177e4
LT		 2469 }
2470 break;
2471
2472 case SCTP_PARAM_STATE_COOKIE:
2473 asoc->peer.cookie_len =
2474 ntohs(param.p->length) - sizeof(sctp_paramhdr_t);
2475 asoc->peer.cookie = param.cookie->body;
2476 break;
2477
2478 case SCTP_PARAM_HEARTBEAT_INFO:
2479 /* Would be odd to receive, but it causes no problems. */
2480 break;
2481
2482 case SCTP_PARAM_UNRECOGNIZED_PARAMETERS:
2483 /* Rejected during verify stage. */
2484 break;
2485
2486 case SCTP_PARAM_ECN_CAPABLE:
2487 asoc->peer.ecn_capable = 1;
2488 break;
2489
0f3fffd8 2490 case SCTP_PARAM_ADAPTATION_LAYER_IND:
e69c4e0f 2491 asoc->peer.adaptation_ind = ntohl(param.aind->adaptation_ind);
1da177e4
LT		 2492 break;
2493
d6de3097 2494 case SCTP_PARAM_SET_PRIMARY:
0ef46e28
VY		 2495 if (!sctp_addip_enable)
2496 goto fall_through;
2497
d6de3097
VY		 2498 addr_param = param.v + sizeof(sctp_addip_param_t);
2499
2500 af = sctp_get_af_specific(param_type2af(param.p->type));
2501 af->from_addr_param(&addr, addr_param,
2502 htons(asoc->peer.port), 0);
2503
2504 /* if the address is invalid, we can't process it.
2505 * XXX: see spec for what to do.
2506 */
2507 if (!af->addr_valid(&addr, NULL, NULL))
2508 break;
2509
2510 t = sctp_assoc_lookup_paddr(asoc, &addr);
2511 if (!t)
2512 break;
2513
2514 sctp_assoc_set_primary(asoc, t);
2515 break;
2516
131a47e3
VY		 2517 case SCTP_PARAM_SUPPORTED_EXT:
2518 sctp_process_ext_param(asoc, param);
2519 break;
2520
1da177e4
LT		 2521 case SCTP_PARAM_FWD_TSN_SUPPORT:
2522 if (sctp_prsctp_enable) {
2523 asoc->peer.prsctp_capable = 1;
2524 break;
2525 }
d808ad9a 2526 /* Fall Through */
730fc3d0
VY		 2527 goto fall_through;
2528
2529 case SCTP_PARAM_RANDOM:
2530 if (!sctp_auth_enable)
2531 goto fall_through;
2532
2533 /* Save peer's random parameter */
2534 asoc->peer.peer_random = kmemdup(param.p,
2535 ntohs(param.p->length), gfp);
2536 if (!asoc->peer.peer_random) {
2537 retval = 0;
2538 break;
2539 }
2540 break;
2541
2542 case SCTP_PARAM_HMAC_ALGO:
2543 if (!sctp_auth_enable)
2544 goto fall_through;
2545
2546 /* Save peer's HMAC list */
2547 asoc->peer.peer_hmacs = kmemdup(param.p,
2548 ntohs(param.p->length), gfp);
2549 if (!asoc->peer.peer_hmacs) {
2550 retval = 0;
2551 break;
2552 }
2553
2554 /* Set the default HMAC the peer requested*/
2555 sctp_auth_asoc_set_default_hmac(asoc, param.hmac_algo);
2556 break;
2557
2558 case SCTP_PARAM_CHUNKS:
2559 if (!sctp_auth_enable)
2560 goto fall_through;
2561
2562 asoc->peer.peer_chunks = kmemdup(param.p,
2563 ntohs(param.p->length), gfp);
2564 if (!asoc->peer.peer_chunks)
2565 retval = 0;
2566 break;
2567fall_through:
1da177e4
LT		 2568 default:
2569 /* Any unrecognized parameters should have been caught
2570 * and handled by sctp_verify_param() which should be
2571 * called prior to this routine. Simply log the error
2572 * here.
2573 */
2574 SCTP_DEBUG_PRINTK("Ignoring param: %d for association %p.\n",
2575 ntohs(param.p->type), asoc);
2576 break;
3ff50b79 2577 }
1da177e4
LT		 2578
2579 return retval;
2580}
2581
2582/* Select a new verification tag. */
2583__u32 sctp_generate_tag(const struct sctp_endpoint *ep)
2584{
2585 /* I believe that this random number generator complies with RFC1750.
2586 * A tag of 0 is reserved for special cases (e.g. INIT).
2587 */
2588 __u32 x;
2589
2590 do {
2591 get_random_bytes(&x, sizeof(__u32));
2592 } while (x == 0);
2593
2594 return x;
2595}
2596
2597/* Select an initial TSN to send during startup. */
2598__u32 sctp_generate_tsn(const struct sctp_endpoint *ep)
2599{
2600 __u32 retval;
2601
2602 get_random_bytes(&retval, sizeof(__u32));
2603 return retval;
2604}
2605
2606/*
2607 * ADDIP 3.1.1 Address Configuration Change Chunk (ASCONF)
2608 * 0 1 2 3
2609 * 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
2610 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2611 * | Type = 0xC1 | Chunk Flags | Chunk Length |
2612 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2613 * | Serial Number |
2614 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2615 * | Address Parameter |
2616 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2617 * | ASCONF Parameter #1 |
2618 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2619 * \ \
2620 * / .... /
2621 * \ \
2622 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2623 * | ASCONF Parameter #N |
2624 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2625 *
d808ad9a 2626 * Address Parameter and other parameter will not be wrapped in this function
1da177e4
LT		 2627 */
2628static struct sctp_chunk *sctp_make_asconf(struct sctp_association *asoc,
2629 union sctp_addr *addr,
2630 int vparam_len)
2631{
2632 sctp_addiphdr_t asconf;
2633 struct sctp_chunk *retval;
2634 int length = sizeof(asconf) + vparam_len;
2635 union sctp_addr_param addrparam;
2636 int addrlen;
2637 struct sctp_af *af = sctp_get_af_specific(addr->v4.sin_family);
2638
2639 addrlen = af->to_addr_param(addr, &addrparam);
2640 if (!addrlen)
2641 return NULL;
2642 length += addrlen;
2643
2644 /* Create the chunk. */
2645 retval = sctp_make_chunk(asoc, SCTP_CID_ASCONF, 0, length);
2646 if (!retval)
2647 return NULL;
2648
2649 asconf.serial = htonl(asoc->addip_serial++);
2650
2651 retval->subh.addip_hdr =
2652 sctp_addto_chunk(retval, sizeof(asconf), &asconf);
2653 retval->param_hdr.v =
2654 sctp_addto_chunk(retval, addrlen, &addrparam);
2655
2656 return retval;
2657}
2658
2659/* ADDIP
2660 * 3.2.1 Add IP Address
2661 * 0 1 2 3
2662 * 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
2663 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2664 * | Type = 0xC001 | Length = Variable |
2665 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2666 * | ASCONF-Request Correlation ID |
2667 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2668 * | Address Parameter |
2669 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2670 *
2671 * 3.2.2 Delete IP Address
2672 * 0 1 2 3
2673 * 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
2674 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2675 * | Type = 0xC002 | Length = Variable |
2676 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2677 * | ASCONF-Request Correlation ID |
2678 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2679 * | Address Parameter |
2680 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2681 *
2682 */
2683struct sctp_chunk *sctp_make_asconf_update_ip(struct sctp_association *asoc,
2684 union sctp_addr *laddr,
2685 struct sockaddr *addrs,
2686 int addrcnt,
dbc16db1 2687 __be16 flags)
1da177e4
LT		 2688{
2689 sctp_addip_param_t param;
2690 struct sctp_chunk *retval;
2691 union sctp_addr_param addr_param;
2692 union sctp_addr *addr;
2693 void *addr_buf;
2694 struct sctp_af *af;
2695 int paramlen = sizeof(param);
2696 int addr_param_len = 0;
2697 int totallen = 0;
2698 int i;
2699
2700 /* Get total length of all the address parameters. */
2701 addr_buf = addrs;
2702 for (i = 0; i < addrcnt; i++) {
2703 addr = (union sctp_addr *)addr_buf;
2704 af = sctp_get_af_specific(addr->v4.sin_family);
2705 addr_param_len = af->to_addr_param(addr, &addr_param);
2706
2707 totallen += paramlen;
2708 totallen += addr_param_len;
2709
2710 addr_buf += af->sockaddr_len;
2711 }
2712
2713 /* Create an asconf chunk with the required length. */
2714 retval = sctp_make_asconf(asoc, laddr, totallen);
2715 if (!retval)
2716 return NULL;
2717
2718 /* Add the address parameters to the asconf chunk. */
2719 addr_buf = addrs;
2720 for (i = 0; i < addrcnt; i++) {
2721 addr = (union sctp_addr *)addr_buf;
2722 af = sctp_get_af_specific(addr->v4.sin_family);
2723 addr_param_len = af->to_addr_param(addr, &addr_param);
2724 param.param_hdr.type = flags;
2725 param.param_hdr.length = htons(paramlen + addr_param_len);
2726 param.crr_id = i;
2727
2728 sctp_addto_chunk(retval, paramlen, &param);
2729 sctp_addto_chunk(retval, addr_param_len, &addr_param);
2730
2731 addr_buf += af->sockaddr_len;
2732 }
2733 return retval;
2734}
2735
2736/* ADDIP
2737 * 3.2.4 Set Primary IP Address
2738 * 0 1 2 3
2739 * 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
2740 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2741 * | Type =0xC004 | Length = Variable |
2742 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2743 * | ASCONF-Request Correlation ID |
2744 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2745 * | Address Parameter |
2746 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2747 *
d808ad9a 2748 * Create an ASCONF chunk with Set Primary IP address parameter.
1da177e4
LT		 2749 */
2750struct sctp_chunk *sctp_make_asconf_set_prim(struct sctp_association *asoc,
2751 union sctp_addr *addr)
2752{
2753 sctp_addip_param_t param;
2754 struct sctp_chunk *retval;
2755 int len = sizeof(param);
2756 union sctp_addr_param addrparam;
2757 int addrlen;
2758 struct sctp_af *af = sctp_get_af_specific(addr->v4.sin_family);
2759
2760 addrlen = af->to_addr_param(addr, &addrparam);
2761 if (!addrlen)
2762 return NULL;
2763 len += addrlen;
2764
2765 /* Create the chunk and make asconf header. */
2766 retval = sctp_make_asconf(asoc, addr, len);
2767 if (!retval)
2768 return NULL;
2769
2770 param.param_hdr.type = SCTP_PARAM_SET_PRIMARY;
2771 param.param_hdr.length = htons(len);
2772 param.crr_id = 0;
2773
2774 sctp_addto_chunk(retval, sizeof(param), &param);
2775 sctp_addto_chunk(retval, addrlen, &addrparam);
2776
2777 return retval;
2778}
2779
2780/* ADDIP 3.1.2 Address Configuration Acknowledgement Chunk (ASCONF-ACK)
2781 * 0 1 2 3
2782 * 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
2783 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2784 * | Type = 0x80 | Chunk Flags | Chunk Length |
2785 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2786 * | Serial Number |
2787 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2788 * | ASCONF Parameter Response#1 |
2789 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2790 * \ \
2791 * / .... /
2792 * \ \
2793 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2794 * | ASCONF Parameter Response#N |
2795 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2796 *
d808ad9a 2797 * Create an ASCONF_ACK chunk with enough space for the parameter responses.
1da177e4
LT		 2798 */
2799static struct sctp_chunk *sctp_make_asconf_ack(const struct sctp_association *asoc,
2800 __u32 serial, int vparam_len)
2801{
2802 sctp_addiphdr_t asconf;
2803 struct sctp_chunk *retval;
2804 int length = sizeof(asconf) + vparam_len;
2805
2806 /* Create the chunk. */
2807 retval = sctp_make_chunk(asoc, SCTP_CID_ASCONF_ACK, 0, length);
2808 if (!retval)
2809 return NULL;
2810
2811 asconf.serial = htonl(serial);
2812
2813 retval->subh.addip_hdr =
2814 sctp_addto_chunk(retval, sizeof(asconf), &asconf);
2815
2816 return retval;
2817}
2818
2819/* Add response parameters to an ASCONF_ACK chunk. */
9f81bcd9 2820static void sctp_add_asconf_response(struct sctp_chunk *chunk, __be32 crr_id,
dbc16db1 2821 __be16 err_code, sctp_addip_param_t *asconf_param)
1da177e4
LT		 2822{
2823 sctp_addip_param_t ack_param;
2824 sctp_errhdr_t err_param;
2825 int asconf_param_len = 0;
2826 int err_param_len = 0;
dbc16db1 2827 __be16 response_type;
1da177e4
LT		 2828
2829 if (SCTP_ERROR_NO_ERROR == err_code) {
2830 response_type = SCTP_PARAM_SUCCESS_REPORT;
2831 } else {
2832 response_type = SCTP_PARAM_ERR_CAUSE;
2833 err_param_len = sizeof(err_param);
2834 if (asconf_param)
2835 asconf_param_len =
2836 ntohs(asconf_param->param_hdr.length);
2837 }
2838
d808ad9a 2839 /* Add Success Indication or Error Cause Indication parameter. */
1da177e4
LT		 2840 ack_param.param_hdr.type = response_type;
2841 ack_param.param_hdr.length = htons(sizeof(ack_param) +
2842 err_param_len +
2843 asconf_param_len);
2844 ack_param.crr_id = crr_id;
2845 sctp_addto_chunk(chunk, sizeof(ack_param), &ack_param);
2846
2847 if (SCTP_ERROR_NO_ERROR == err_code)
2848 return;
2849
2850 /* Add Error Cause parameter. */
2851 err_param.cause = err_code;
2852 err_param.length = htons(err_param_len + asconf_param_len);
2853 sctp_addto_chunk(chunk, err_param_len, &err_param);
2854
2855 /* Add the failed TLV copied from ASCONF chunk. */
2856 if (asconf_param)
2857 sctp_addto_chunk(chunk, asconf_param_len, asconf_param);
2858}
2859
2860/* Process a asconf parameter. */
dbc16db1 2861static __be16 sctp_process_asconf_param(struct sctp_association *asoc,
1da177e4
LT		 2862 struct sctp_chunk *asconf,
2863 sctp_addip_param_t *asconf_param)
2864{
2865 struct sctp_transport *peer;
2866 struct sctp_af *af;
2867 union sctp_addr addr;
1da177e4 2868 union sctp_addr_param *addr_param;
5f242a13 2869
c1cc678a
PM		 2870 addr_param = (union sctp_addr_param *)
2871 ((void *)asconf_param + sizeof(sctp_addip_param_t));
2872
44e65c1e
WY		 2873 if (asconf_param->param_hdr.type != SCTP_PARAM_ADD_IP &&
2874 asconf_param->param_hdr.type != SCTP_PARAM_DEL_IP &&
2875 asconf_param->param_hdr.type != SCTP_PARAM_SET_PRIMARY)
2876 return SCTP_ERROR_UNKNOWN_PARAM;
2877
c4492586
WY		 2878 switch (addr_param->v4.param_hdr.type) {
2879 case SCTP_PARAM_IPV6_ADDRESS:
2880 if (!asoc->peer.ipv6_address)
945e5abc 2881 return SCTP_ERROR_DNS_FAILED;
c4492586
WY		 2882 break;
2883 case SCTP_PARAM_IPV4_ADDRESS:
2884 if (!asoc->peer.ipv4_address)
945e5abc 2885 return SCTP_ERROR_DNS_FAILED;
c4492586
WY		 2886 break;
2887 default:
945e5abc 2888 return SCTP_ERROR_DNS_FAILED;
c4492586
WY		 2889 }
2890
1da177e4
LT		 2891 af = sctp_get_af_specific(param_type2af(addr_param->v4.param_hdr.type));
2892 if (unlikely(!af))
945e5abc 2893 return SCTP_ERROR_DNS_FAILED;
1da177e4 2894
dd86d136 2895 af->from_addr_param(&addr, addr_param, htons(asoc->peer.port), 0);
42e30bf3
VY		 2896
2897 /* ADDIP 4.2.1 This parameter MUST NOT contain a broadcast
2898 * or multicast address.
2899 * (note: wildcard is permitted and requires special handling so
2900 * make sure we check for that)
2901 */
2902 if (!af->is_any(&addr) && !af->addr_valid(&addr, NULL, asconf->skb))
945e5abc 2903 return SCTP_ERROR_DNS_FAILED;
42e30bf3 2904
1da177e4
LT		 2905 switch (asconf_param->param_hdr.type) {
2906 case SCTP_PARAM_ADD_IP:
42e30bf3
VY		 2907 /* Section 4.2.1:
2908 * If the address 0.0.0.0 or ::0 is provided, the source
2909 * address of the packet MUST be added.
2910 */
2911 if (af->is_any(&addr))
2912 memcpy(&addr, &asconf->source, sizeof(addr));
2913
1da177e4 2914 /* ADDIP 4.3 D9) If an endpoint receives an ADD IP address
d808ad9a
YH		 2915 * request and does not have the local resources to add this
2916 * new address to the association, it MUST return an Error
2917 * Cause TLV set to the new error code 'Operation Refused
2918 * Due to Resource Shortage'.
2919 */
1da177e4 2920
dd86d136 2921 peer = sctp_assoc_add_peer(asoc, &addr, GFP_ATOMIC, SCTP_UNCONFIRMED);
1da177e4
LT		 2922 if (!peer)
2923 return SCTP_ERROR_RSRC_LOW;
2924
2925 /* Start the heartbeat timer. */
2926 if (!mod_timer(&peer->hb_timer, sctp_transport_timeout(peer)))
2927 sctp_transport_hold(peer);
2928 break;
2929 case SCTP_PARAM_DEL_IP:
2930 /* ADDIP 4.3 D7) If a request is received to delete the
d808ad9a
YH		 2931 * last remaining IP address of a peer endpoint, the receiver
2932 * MUST send an Error Cause TLV with the error cause set to the
2933 * new error code 'Request to Delete Last Remaining IP Address'.
2934 */
42e30bf3 2935 if (asoc->peer.transport_count == 1)
1da177e4
LT		 2936 return SCTP_ERROR_DEL_LAST_IP;
2937
2938 /* ADDIP 4.3 D8) If a request is received to delete an IP
2939 * address which is also the source address of the IP packet
2940 * which contained the ASCONF chunk, the receiver MUST reject
2941 * this request. To reject the request the receiver MUST send
2942 * an Error Cause TLV set to the new error code 'Request to
2943 * Delete Source IP Address'
2944 */
6a1e5f33 2945 if (sctp_cmp_addr_exact(sctp_source(asconf), &addr))
1da177e4
LT		 2946 return SCTP_ERROR_DEL_SRC_IP;
2947
42e30bf3
VY		 2948 /* Section 4.2.2
2949 * If the address 0.0.0.0 or ::0 is provided, all
2950 * addresses of the peer except the source address of the
2951 * packet MUST be deleted.
2952 */
2953 if (af->is_any(&addr)) {
2954 sctp_assoc_set_primary(asoc, asconf->transport);
2955 sctp_assoc_del_nonprimary_peers(asoc,
2956 asconf->transport);
2957 } else
2958 sctp_assoc_del_peer(asoc, &addr);
1da177e4
LT		 2959 break;
2960 case SCTP_PARAM_SET_PRIMARY:
42e30bf3
VY		 2961 /* ADDIP Section 4.2.4
2962 * If the address 0.0.0.0 or ::0 is provided, the receiver
2963 * MAY mark the source address of the packet as its
2964 * primary.
2965 */
2966 if (af->is_any(&addr))
2967 memcpy(&addr.v4, sctp_source(asconf), sizeof(addr));
2968
dd86d136 2969 peer = sctp_assoc_lookup_paddr(asoc, &addr);
1da177e4 2970 if (!peer)
945e5abc 2971 return SCTP_ERROR_DNS_FAILED;
1da177e4
LT		 2972
2973 sctp_assoc_set_primary(asoc, peer);
2974 break;
1da177e4
LT		 2975 }
2976
2977 return SCTP_ERROR_NO_ERROR;
2978}
2979
6f4c618d
WY		 2980/* Verify the ASCONF packet before we process it. */
2981int sctp_verify_asconf(const struct sctp_association *asoc,
2982 struct sctp_paramhdr *param_hdr, void *chunk_end,
2983 struct sctp_paramhdr **errp) {
2984 sctp_addip_param_t *asconf_param;
2985 union sctp_params param;
2986 int length, plen;
2987
2988 param.v = (sctp_paramhdr_t *) param_hdr;
2989 while (param.v <= chunk_end - sizeof(sctp_paramhdr_t)) {
2990 length = ntohs(param.p->length);
2991 *errp = param.p;
2992
2993 if (param.v > chunk_end - length ||
2994 length < sizeof(sctp_paramhdr_t))
2995 return 0;
2996
2997 switch (param.p->type) {
2998 case SCTP_PARAM_ADD_IP:
2999 case SCTP_PARAM_DEL_IP:
3000 case SCTP_PARAM_SET_PRIMARY:
3001 asconf_param = (sctp_addip_param_t *)param.v;
3002 plen = ntohs(asconf_param->param_hdr.length);
3003 if (plen < sizeof(sctp_addip_param_t) +
3004 sizeof(sctp_paramhdr_t))
3005 return 0;
3006 break;
3007 case SCTP_PARAM_SUCCESS_REPORT:
3008 case SCTP_PARAM_ADAPTATION_LAYER_IND:
3009 if (length != sizeof(sctp_addip_param_t))
3010 return 0;
3011
3012 break;
3013 default:
3014 break;
3015 }
3016
3017 param.v += WORD_ROUND(length);
3018 }
3019
3020 if (param.v != chunk_end)
3021 return 0;
3022
3023 return 1;
3024}
3025
d808ad9a 3026/* Process an incoming ASCONF chunk with the next expected serial no. and
1da177e4
LT		 3027 * return an ASCONF_ACK chunk to be sent in response.
3028 */
3029struct sctp_chunk *sctp_process_asconf(struct sctp_association *asoc,
3030 struct sctp_chunk *asconf)
3031{
3032 sctp_addiphdr_t *hdr;
3033 union sctp_addr_param *addr_param;
3034 sctp_addip_param_t *asconf_param;
3035 struct sctp_chunk *asconf_ack;
3036
dbc16db1 3037 __be16 err_code;
1da177e4 3038 int length = 0;
f3830ccc 3039 int chunk_len;
1da177e4
LT		 3040 __u32 serial;
3041 int all_param_pass = 1;
3042
f3830ccc 3043 chunk_len = ntohs(asconf->chunk_hdr->length) - sizeof(sctp_chunkhdr_t);
1da177e4
LT		 3044 hdr = (sctp_addiphdr_t *)asconf->skb->data;
3045 serial = ntohl(hdr->serial);
3046
d808ad9a 3047 /* Skip the addiphdr and store a pointer to address parameter. */
1da177e4
LT		 3048 length = sizeof(sctp_addiphdr_t);
3049 addr_param = (union sctp_addr_param *)(asconf->skb->data + length);
3050 chunk_len -= length;
3051
3052 /* Skip the address parameter and store a pointer to the first
7aa1b54b 3053 * asconf parameter.
d808ad9a 3054 */
1da177e4
LT		 3055 length = ntohs(addr_param->v4.param_hdr.length);
3056 asconf_param = (sctp_addip_param_t *)((void *)addr_param + length);
3057 chunk_len -= length;
3058
d808ad9a 3059 /* create an ASCONF_ACK chunk.
1da177e4
LT		 3060 * Based on the definitions of parameters, we know that the size of
3061 * ASCONF_ACK parameters are less than or equal to the twice of ASCONF
7aa1b54b 3062 * parameters.
1da177e4
LT		 3063 */
3064 asconf_ack = sctp_make_asconf_ack(asoc, serial, chunk_len * 2);
3065 if (!asconf_ack)
3066 goto done;
3067
3068 /* Process the TLVs contained within the ASCONF chunk. */
3069 while (chunk_len > 0) {
3070 err_code = sctp_process_asconf_param(asoc, asconf,
3071 asconf_param);
3072 /* ADDIP 4.1 A7)
3073 * If an error response is received for a TLV parameter,
3074 * all TLVs with no response before the failed TLV are
3075 * considered successful if not reported. All TLVs after
3076 * the failed response are considered unsuccessful unless
3077 * a specific success indication is present for the parameter.
3078 */
3079 if (SCTP_ERROR_NO_ERROR != err_code)
3080 all_param_pass = 0;
3081
3082 if (!all_param_pass)
3083 sctp_add_asconf_response(asconf_ack,
3084 asconf_param->crr_id, err_code,
3085 asconf_param);
3086
3087 /* ADDIP 4.3 D11) When an endpoint receiving an ASCONF to add
3088 * an IP address sends an 'Out of Resource' in its response, it
3089 * MUST also fail any subsequent add or delete requests bundled
d808ad9a 3090 * in the ASCONF.
1da177e4
LT		 3091 */
3092 if (SCTP_ERROR_RSRC_LOW == err_code)
3093 goto done;
3094
3095 /* Move to the next ASCONF param. */
3096 length = ntohs(asconf_param->param_hdr.length);
3097 asconf_param = (sctp_addip_param_t *)((void *)asconf_param +
3098 length);
3099 chunk_len -= length;
3100 }
d808ad9a 3101
1da177e4
LT		 3102done:
3103 asoc->peer.addip_serial++;
3104
3105 /* If we are sending a new ASCONF_ACK hold a reference to it in assoc
d808ad9a 3106 * after freeing the reference to old asconf ack if any.
1da177e4
LT		 3107 */
3108 if (asconf_ack) {
1da177e4 3109 sctp_chunk_hold(asconf_ack);
a08de64d
VY		 3110 list_add_tail(&asconf_ack->transmitted_list,
3111 &asoc->asconf_ack_list);
1da177e4
LT		 3112 }
3113
3114 return asconf_ack;
3115}
3116
3117/* Process a asconf parameter that is successfully acked. */
425e0f68 3118static void sctp_asconf_param_success(struct sctp_association *asoc,
1da177e4
LT		 3119 sctp_addip_param_t *asconf_param)
3120{
3121 struct sctp_af *af;
3122 union sctp_addr addr;
3123 struct sctp_bind_addr *bp = &asoc->base.bind_addr;
3124 union sctp_addr_param *addr_param;
1da177e4 3125 struct sctp_transport *transport;
dc022a98 3126 struct sctp_sockaddr_entry *saddr;
1da177e4
LT		 3127
3128 addr_param = (union sctp_addr_param *)
3129 ((void *)asconf_param + sizeof(sctp_addip_param_t));
3130
3131 /* We have checked the packet before, so we do not check again. */
3132 af = sctp_get_af_specific(param_type2af(addr_param->v4.param_hdr.type));
dd86d136 3133 af->from_addr_param(&addr, addr_param, htons(bp->port), 0);
1da177e4
LT		 3134
3135 switch (asconf_param->param_hdr.type) {
3136 case SCTP_PARAM_ADD_IP:
559cf710
VY		 3137 /* This is always done in BH context with a socket lock
3138 * held, so the list can not change.
3139 */
0ed90fb0 3140 local_bh_disable();
559cf710 3141 list_for_each_entry(saddr, &bp->address_list, list) {
dd86d136 3142 if (sctp_cmp_addr_exact(&saddr->a, &addr))
f57d96b2 3143 saddr->state = SCTP_ADDR_SRC;
dc022a98 3144 }
0ed90fb0 3145 local_bh_enable();
3cd9749c
WY		 3146 list_for_each_entry(transport, &asoc->peer.transport_addr_list,
3147 transports) {
3148 if (transport->state == SCTP_ACTIVE)
3149 continue;
3150 dst_release(transport->dst);
3151 sctp_transport_route(transport, NULL,
3152 sctp_sk(asoc->base.sk));
3153 }
1da177e4
LT		 3154 break;
3155 case SCTP_PARAM_DEL_IP:
0ed90fb0 3156 local_bh_disable();
425e0f68 3157 sctp_del_bind_addr(bp, &addr);
0ed90fb0 3158 local_bh_enable();
9dbc15f0
RD		 3159 list_for_each_entry(transport, &asoc->peer.transport_addr_list,
3160 transports) {
dc022a98 3161 dst_release(transport->dst);
1da177e4
LT		 3162 sctp_transport_route(transport, NULL,
3163 sctp_sk(asoc->base.sk));
3164 }
3165 break;
3166 default:
3167 break;
3168 }
1da177e4
LT		 3169}
3170
3171/* Get the corresponding ASCONF response error code from the ASCONF_ACK chunk
3172 * for the given asconf parameter. If there is no response for this parameter,
d808ad9a 3173 * return the error code based on the third argument 'no_err'.
1da177e4
LT		 3174 * ADDIP 4.1
3175 * A7) If an error response is received for a TLV parameter, all TLVs with no
3176 * response before the failed TLV are considered successful if not reported.
3177 * All TLVs after the failed response are considered unsuccessful unless a
3178 * specific success indication is present for the parameter.
3179 */
dbc16db1 3180static __be16 sctp_get_asconf_response(struct sctp_chunk *asconf_ack,
1da177e4
LT		 3181 sctp_addip_param_t *asconf_param,
3182 int no_err)
3183{
3184 sctp_addip_param_t *asconf_ack_param;
3185 sctp_errhdr_t *err_param;
3186 int length;
f3830ccc 3187 int asconf_ack_len;
dbc16db1 3188 __be16 err_code;
1da177e4
LT		 3189
3190 if (no_err)
3191 err_code = SCTP_ERROR_NO_ERROR;
3192 else
3193 err_code = SCTP_ERROR_REQ_REFUSED;
3194
f3830ccc
WY		 3195 asconf_ack_len = ntohs(asconf_ack->chunk_hdr->length) -
3196 sizeof(sctp_chunkhdr_t);
3197
1da177e4
LT		 3198 /* Skip the addiphdr from the asconf_ack chunk and store a pointer to
3199 * the first asconf_ack parameter.
d808ad9a 3200 */
1da177e4
LT		 3201 length = sizeof(sctp_addiphdr_t);
3202 asconf_ack_param = (sctp_addip_param_t *)(asconf_ack->skb->data +
3203 length);
3204 asconf_ack_len -= length;
3205
3206 while (asconf_ack_len > 0) {
3207 if (asconf_ack_param->crr_id == asconf_param->crr_id) {
3208 switch(asconf_ack_param->param_hdr.type) {
3209 case SCTP_PARAM_SUCCESS_REPORT:
3210 return SCTP_ERROR_NO_ERROR;
3211 case SCTP_PARAM_ERR_CAUSE:
3212 length = sizeof(sctp_addip_param_t);
3213 err_param = (sctp_errhdr_t *)
3214 ((void *)asconf_ack_param + length);
3215 asconf_ack_len -= length;
3216 if (asconf_ack_len > 0)
3217 return err_param->cause;
3218 else
3219 return SCTP_ERROR_INV_PARAM;
3220 break;
3221 default:
3222 return SCTP_ERROR_INV_PARAM;
3223 }
3224 }
3225
3226 length = ntohs(asconf_ack_param->param_hdr.length);
3227 asconf_ack_param = (sctp_addip_param_t *)
3228 ((void *)asconf_ack_param + length);
3229 asconf_ack_len -= length;
3230 }
3231
3232 return err_code;
3233}
3234
3235/* Process an incoming ASCONF_ACK chunk against the cached last ASCONF chunk. */
3236int sctp_process_asconf_ack(struct sctp_association *asoc,
3237 struct sctp_chunk *asconf_ack)
3238{
3239 struct sctp_chunk *asconf = asoc->addip_last_asconf;
3240 union sctp_addr_param *addr_param;
3241 sctp_addip_param_t *asconf_param;
3242 int length = 0;
3243 int asconf_len = asconf->skb->len;
3244 int all_param_pass = 0;
3245 int no_err = 1;
3246 int retval = 0;
dbc16db1 3247 __be16 err_code = SCTP_ERROR_NO_ERROR;
1da177e4
LT		 3248
3249 /* Skip the chunkhdr and addiphdr from the last asconf sent and store
3250 * a pointer to address parameter.
d808ad9a 3251 */
1da177e4
LT		 3252 length = sizeof(sctp_addip_chunk_t);
3253 addr_param = (union sctp_addr_param *)(asconf->skb->data + length);
3254 asconf_len -= length;
3255
3256 /* Skip the address parameter in the last asconf sent and store a
7aa1b54b 3257 * pointer to the first asconf parameter.
d808ad9a 3258 */
1da177e4
LT		 3259 length = ntohs(addr_param->v4.param_hdr.length);
3260 asconf_param = (sctp_addip_param_t *)((void *)addr_param + length);
3261 asconf_len -= length;
3262
3263 /* ADDIP 4.1
3264 * A8) If there is no response(s) to specific TLV parameter(s), and no
3265 * failures are indicated, then all request(s) are considered
3266 * successful.
3267 */
3268 if (asconf_ack->skb->len == sizeof(sctp_addiphdr_t))
3269 all_param_pass = 1;
3270
3271 /* Process the TLVs contained in the last sent ASCONF chunk. */
3272 while (asconf_len > 0) {
3273 if (all_param_pass)
3274 err_code = SCTP_ERROR_NO_ERROR;
3275 else {
3276 err_code = sctp_get_asconf_response(asconf_ack,
3277 asconf_param,
3278 no_err);
3279 if (no_err && (SCTP_ERROR_NO_ERROR != err_code))
3280 no_err = 0;
3281 }
3282
3283 switch (err_code) {
3284 case SCTP_ERROR_NO_ERROR:
425e0f68 3285 sctp_asconf_param_success(asoc, asconf_param);
1da177e4
LT		 3286 break;
3287
3288 case SCTP_ERROR_RSRC_LOW:
3289 retval = 1;
3290 break;
3291
a987f762 3292 case SCTP_ERROR_UNKNOWN_PARAM:
1da177e4
LT		 3293 /* Disable sending this type of asconf parameter in
3294 * future.
d808ad9a 3295 */
1da177e4
LT		 3296 asoc->peer.addip_disabled_mask |=
3297 asconf_param->param_hdr.type;
3298 break;
3299
3300 case SCTP_ERROR_REQ_REFUSED:
3301 case SCTP_ERROR_DEL_LAST_IP:
3302 case SCTP_ERROR_DEL_SRC_IP:
3303 default:
3304 break;
3305 }
3306
3307 /* Skip the processed asconf parameter and move to the next
3308 * one.
d808ad9a 3309 */
1da177e4
LT		 3310 length = ntohs(asconf_param->param_hdr.length);
3311 asconf_param = (sctp_addip_param_t *)((void *)asconf_param +
3312 length);
3313 asconf_len -= length;
3314 }
3315
3316 /* Free the cached last sent asconf chunk. */
5f9646c3 3317 list_del_init(&asconf->transmitted_list);
1da177e4
LT		 3318 sctp_chunk_free(asconf);
3319 asoc->addip_last_asconf = NULL;
3320
3321 /* Send the next asconf chunk from the addip chunk queue. */
79af02c2
DM		 3322 if (!list_empty(&asoc->addip_chunk_list)) {
3323 struct list_head *entry = asoc->addip_chunk_list.next;
3324 asconf = list_entry(entry, struct sctp_chunk, list);
3325
3326 list_del_init(entry);
3327
1da177e4
LT		 3328 /* Hold the chunk until an ASCONF_ACK is received. */
3329 sctp_chunk_hold(asconf);
3330 if (sctp_primitive_ASCONF(asoc, asconf))
3331 sctp_chunk_free(asconf);
3332 else
3333 asoc->addip_last_asconf = asconf;
3334 }
3335
3336 return retval;
3337}
3338
d808ad9a 3339/* Make a FWD TSN chunk. */
1da177e4
LT		 3340struct sctp_chunk *sctp_make_fwdtsn(const struct sctp_association *asoc,
3341 __u32 new_cum_tsn, size_t nstreams,
3342 struct sctp_fwdtsn_skip *skiplist)
3343{
3344 struct sctp_chunk *retval = NULL;
3345 struct sctp_fwdtsn_chunk *ftsn_chunk;
d808ad9a 3346 struct sctp_fwdtsn_hdr ftsn_hdr;
1da177e4
LT		 3347 struct sctp_fwdtsn_skip skip;
3348 size_t hint;
3349 int i;
3350
3351 hint = (nstreams + 1) * sizeof(__u32);
3352
1da177e4
LT		 3353 retval = sctp_make_chunk(asoc, SCTP_CID_FWD_TSN, 0, hint);
3354
3355 if (!retval)
3356 return NULL;
3357
3358 ftsn_chunk = (struct sctp_fwdtsn_chunk *)retval->subh.fwdtsn_hdr;
3359
3360 ftsn_hdr.new_cum_tsn = htonl(new_cum_tsn);
3361 retval->subh.fwdtsn_hdr =
3362 sctp_addto_chunk(retval, sizeof(ftsn_hdr), &ftsn_hdr);
3363
3364 for (i = 0; i < nstreams; i++) {
3365 skip.stream = skiplist[i].stream;
3366 skip.ssn = skiplist[i].ssn;
3367 sctp_addto_chunk(retval, sizeof(skip), &skip);
3368 }
3369
3370 return retval;
3371}
Linux 6.x block layer and io_uring tree(s)