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