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[linux-2.6-block.git] / net / sctp / sm_make_chunk.c
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60c778b2 1/* SCTP kernel implementation
1da177e4
LT		 2 * (C) Copyright IBM Corp. 2001, 2004
3 * Copyright (c) 1999-2000 Cisco, Inc.
4 * Copyright (c) 1999-2001 Motorola, Inc.
5 * Copyright (c) 2001-2002 Intel Corp.
6 *
60c778b2 7 * This file is part of the SCTP kernel implementation
1da177e4
LT		 8 *
9 * These functions work with the state functions in sctp_sm_statefuns.c
10 * to implement the state operations. These functions implement the
11 * steps which require modifying existing data structures.
12 *
60c778b2 13 * This SCTP implementation is free software;
1da177e4
LT		 14 * you can redistribute it and/or modify it under the terms of
15 * the GNU General Public License as published by
16 * the Free Software Foundation; either version 2, or (at your option)
17 * any later version.
18 *
60c778b2 19 * This SCTP implementation is distributed in the hope that it
1da177e4
LT		 20 * will be useful, but WITHOUT ANY WARRANTY; without even the implied
21 * ************************
22 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
23 * See the GNU General Public License for more details.
24 *
25 * You should have received a copy of the GNU General Public License
26 * along with GNU CC; see the file COPYING. If not, write to
27 * the Free Software Foundation, 59 Temple Place - Suite 330,
28 * Boston, MA 02111-1307, USA.
29 *
30 * Please send any bug reports or fixes you make to the
31 * email address(es):
32 * lksctp developers <lksctp-developers@lists.sourceforge.net>
33 *
34 * Or submit a bug report through the following website:
35 * http://www.sf.net/projects/lksctp
36 *
37 * Written or modified by:
38 * La Monte H.P. Yarroll <piggy@acm.org>
39 * Karl Knutson <karl@athena.chicago.il.us>
40 * C. Robin <chris@hundredacre.ac.uk>
41 * Jon Grimm <jgrimm@us.ibm.com>
42 * Xingang Guo <xingang.guo@intel.com>
43 * Dajiang Zhang <dajiang.zhang@nokia.com>
44 * Sridhar Samudrala <sri@us.ibm.com>
45 * Daisy Chang <daisyc@us.ibm.com>
46 * Ardelle Fan <ardelle.fan@intel.com>
47 * Kevin Gao <kevin.gao@intel.com>
48 *
49 * Any bugs reported given to us we will try to fix... any fixes shared will
50 * be incorporated into the next SCTP release.
51 */
52
53#include <linux/types.h>
54#include <linux/kernel.h>
55#include <linux/ip.h>
56#include <linux/ipv6.h>
57#include <linux/net.h>
58#include <linux/inet.h>
ebc3bbcf 59#include <linux/scatterlist.h>
1da177e4
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,
103 __constant_htons(sizeof(struct sctp_paramhdr)),
104};
105static const struct sctp_paramhdr prsctp_param = {
106 SCTP_PARAM_FWD_TSN_SUPPORT,
107 __constant_htons(sizeof(struct sctp_paramhdr)),
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
1da177e4
LT		 227 chunksize += sizeof(aiparam);
228 chunksize += vparam_len;
229
730fc3d0
VY		 230 /* Account for AUTH related parameters */
231 if (sctp_auth_enable) {
232 /* Add random parameter length*/
233 chunksize += sizeof(asoc->c.auth_random);
234
235 /* Add HMACS parameter length if any were defined */
236 auth_hmacs = (sctp_paramhdr_t *)asoc->c.auth_hmacs;
237 if (auth_hmacs->length)
238 chunksize += ntohs(auth_hmacs->length);
239 else
240 auth_hmacs = NULL;
241
242 /* Add CHUNKS parameter length */
243 auth_chunks = (sctp_paramhdr_t *)asoc->c.auth_chunks;
244 if (auth_chunks->length)
245 chunksize += ntohs(auth_chunks->length);
246 else
9baffaa6 247 auth_chunks = NULL;
730fc3d0
VY		 248
249 extensions[num_ext] = SCTP_CID_AUTH;
250 num_ext += 1;
251 }
252
131a47e3
VY		 253 /* If we have any extensions to report, account for that */
254 if (num_ext)
255 chunksize += sizeof(sctp_supported_ext_param_t) + num_ext;
256
1da177e4
LT		 257 /* RFC 2960 3.3.2 Initiation (INIT) (1)
258 *
259 * Note 3: An INIT chunk MUST NOT contain more than one Host
260 * Name address parameter. Moreover, the sender of the INIT
261 * MUST NOT combine any other address types with the Host Name
262 * address in the INIT. The receiver of INIT MUST ignore any
263 * other address types if the Host Name address parameter is
264 * present in the received INIT chunk.
265 *
266 * PLEASE DO NOT FIXME [This version does not support Host Name.]
267 */
268
269 retval = sctp_make_chunk(asoc, SCTP_CID_INIT, 0, chunksize);
270 if (!retval)
271 goto nodata;
272
273 retval->subh.init_hdr =
274 sctp_addto_chunk(retval, sizeof(init), &init);
275 retval->param_hdr.v =
276 sctp_addto_chunk(retval, addrs_len, addrs.v);
277
278 /* RFC 2960 3.3.2 Initiation (INIT) (1)
279 *
280 * Note 4: This parameter, when present, specifies all the
281 * address types the sending endpoint can support. The absence
282 * of this parameter indicates that the sending endpoint can
283 * support any address type.
284 */
285 sat.param_hdr.type = SCTP_PARAM_SUPPORTED_ADDRESS_TYPES;
286 sat.param_hdr.length = htons(SCTP_SAT_LEN(num_types));
287 sctp_addto_chunk(retval, sizeof(sat), &sat);
288 sctp_addto_chunk(retval, num_types * sizeof(__u16), &types);
289
290 sctp_addto_chunk(retval, sizeof(ecap_param), &ecap_param);
131a47e3 291
7aa1b54b 292 /* Add the supported extensions parameter. Be nice and add this
131a47e3
VY		 293 * fist before addiding the parameters for the extensions themselves
294 */
295 if (num_ext) {
296 ext_param.param_hdr.type = SCTP_PARAM_SUPPORTED_EXT;
297 ext_param.param_hdr.length =
298 htons(sizeof(sctp_supported_ext_param_t) + num_ext);
299 sctp_addto_chunk(retval, sizeof(sctp_supported_ext_param_t),
300 &ext_param);
8ee4be37 301 sctp_addto_param(retval, num_ext, extensions);
131a47e3
VY		 302 }
303
1da177e4
LT		 304 if (sctp_prsctp_enable)
305 sctp_addto_chunk(retval, sizeof(prsctp_param), &prsctp_param);
131a47e3 306
0f3fffd8 307 aiparam.param_hdr.type = SCTP_PARAM_ADAPTATION_LAYER_IND;
1da177e4 308 aiparam.param_hdr.length = htons(sizeof(aiparam));
0f3fffd8 309 aiparam.adaptation_ind = htonl(sp->adaptation_ind);
1da177e4 310 sctp_addto_chunk(retval, sizeof(aiparam), &aiparam);
131a47e3 311
730fc3d0
VY		 312 /* Add SCTP-AUTH chunks to the parameter list */
313 if (sctp_auth_enable) {
314 sctp_addto_chunk(retval, sizeof(asoc->c.auth_random),
315 asoc->c.auth_random);
316 if (auth_hmacs)
317 sctp_addto_chunk(retval, ntohs(auth_hmacs->length),
318 auth_hmacs);
319 if (auth_chunks)
320 sctp_addto_chunk(retval, ntohs(auth_chunks->length),
321 auth_chunks);
322 }
1da177e4 323nodata:
a51482bd 324 kfree(addrs.v);
1da177e4
LT		 325 return retval;
326}
327
328struct sctp_chunk *sctp_make_init_ack(const struct sctp_association *asoc,
329 const struct sctp_chunk *chunk,
dd0fc66f 330 gfp_t gfp, int unkparam_len)
1da177e4
LT		 331{
332 sctp_inithdr_t initack;
333 struct sctp_chunk *retval;
334 union sctp_params addrs;
335 int addrs_len;
336 sctp_cookie_param_t *cookie;
337 int cookie_len;
338 size_t chunksize;
0f3fffd8 339 sctp_adaptation_ind_param_t aiparam;
131a47e3
VY		 340 sctp_supported_ext_param_t ext_param;
341 int num_ext = 0;
342 __u8 extensions[3];
730fc3d0
VY		 343 sctp_paramhdr_t *auth_chunks = NULL,
344 *auth_hmacs = NULL,
345 *auth_random = NULL;
1da177e4
LT		 346
347 retval = NULL;
348
349 /* Note: there may be no addresses to embed. */
350 addrs = sctp_bind_addrs_to_raw(&asoc->base.bind_addr, &addrs_len, gfp);
351
352 initack.init_tag = htonl(asoc->c.my_vtag);
353 initack.a_rwnd = htonl(asoc->rwnd);
354 initack.num_outbound_streams = htons(asoc->c.sinit_num_ostreams);
355 initack.num_inbound_streams = htons(asoc->c.sinit_max_instreams);
356 initack.initial_tsn = htonl(asoc->c.initial_tsn);
357
358 /* FIXME: We really ought to build the cookie right
359 * into the packet instead of allocating more fresh memory.
360 */
361 cookie = sctp_pack_cookie(asoc->ep, asoc, chunk, &cookie_len,
362 addrs.v, addrs_len);
363 if (!cookie)
364 goto nomem_cookie;
365
366 /* Calculate the total size of allocation, include the reserved
367 * space for reporting unknown parameters if it is specified.
368 */
369 chunksize = sizeof(initack) + addrs_len + cookie_len + unkparam_len;
370
d808ad9a 371 /* Tell peer that we'll do ECN only if peer advertised such cap. */
1da177e4
LT		 372 if (asoc->peer.ecn_capable)
373 chunksize += sizeof(ecap_param);
374
036b579b
VY		 375 if (sctp_prsctp_enable)
376 chunksize += sizeof(prsctp_param);
377
131a47e3
VY		 378 if (sctp_addip_enable) {
379 extensions[num_ext] = SCTP_CID_ASCONF;
380 extensions[num_ext+1] = SCTP_CID_ASCONF_ACK;
381 num_ext += 2;
382 }
383
1da177e4
LT		 384 chunksize += sizeof(aiparam);
385
730fc3d0
VY		 386 if (asoc->peer.auth_capable) {
387 auth_random = (sctp_paramhdr_t *)asoc->c.auth_random;
388 chunksize += ntohs(auth_random->length);
389
390 auth_hmacs = (sctp_paramhdr_t *)asoc->c.auth_hmacs;
391 if (auth_hmacs->length)
392 chunksize += ntohs(auth_hmacs->length);
393 else
394 auth_hmacs = NULL;
395
396 auth_chunks = (sctp_paramhdr_t *)asoc->c.auth_chunks;
397 if (auth_chunks->length)
398 chunksize += ntohs(auth_chunks->length);
399 else
400 auth_chunks = NULL;
401
402 extensions[num_ext] = SCTP_CID_AUTH;
403 num_ext += 1;
404 }
405
8ee4be37
VY		 406 if (num_ext)
407 chunksize += sizeof(sctp_supported_ext_param_t) + num_ext;
408
1da177e4
LT		 409 /* Now allocate and fill out the chunk. */
410 retval = sctp_make_chunk(asoc, SCTP_CID_INIT_ACK, 0, chunksize);
411 if (!retval)
412 goto nomem_chunk;
413
414 /* Per the advice in RFC 2960 6.4, send this reply to
415 * the source of the INIT packet.
416 */
417 retval->transport = chunk->transport;
418 retval->subh.init_hdr =
419 sctp_addto_chunk(retval, sizeof(initack), &initack);
420 retval->param_hdr.v = sctp_addto_chunk(retval, addrs_len, addrs.v);
421 sctp_addto_chunk(retval, cookie_len, cookie);
422 if (asoc->peer.ecn_capable)
423 sctp_addto_chunk(retval, sizeof(ecap_param), &ecap_param);
131a47e3
VY		 424 if (num_ext) {
425 ext_param.param_hdr.type = SCTP_PARAM_SUPPORTED_EXT;
426 ext_param.param_hdr.length =
427 htons(sizeof(sctp_supported_ext_param_t) + num_ext);
428 sctp_addto_chunk(retval, sizeof(sctp_supported_ext_param_t),
429 &ext_param);
8ee4be37 430 sctp_addto_param(retval, num_ext, extensions);
131a47e3 431 }
1da177e4
LT		 432 if (asoc->peer.prsctp_capable)
433 sctp_addto_chunk(retval, sizeof(prsctp_param), &prsctp_param);
434
0f3fffd8 435 aiparam.param_hdr.type = SCTP_PARAM_ADAPTATION_LAYER_IND;
1da177e4 436 aiparam.param_hdr.length = htons(sizeof(aiparam));
0f3fffd8 437 aiparam.adaptation_ind = htonl(sctp_sk(asoc->base.sk)->adaptation_ind);
1da177e4
LT		 438 sctp_addto_chunk(retval, sizeof(aiparam), &aiparam);
439
730fc3d0
VY		 440 if (asoc->peer.auth_capable) {
441 sctp_addto_chunk(retval, ntohs(auth_random->length),
442 auth_random);
443 if (auth_hmacs)
444 sctp_addto_chunk(retval, ntohs(auth_hmacs->length),
445 auth_hmacs);
446 if (auth_chunks)
447 sctp_addto_chunk(retval, ntohs(auth_chunks->length),
448 auth_chunks);
449 }
450
1da177e4
LT		 451 /* We need to remove the const qualifier at this point. */
452 retval->asoc = (struct sctp_association *) asoc;
453
454 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
455 *
456 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
457 * HEARTBEAT ACK, * etc.) to the same destination transport
458 * address from which it received the DATA or control chunk
459 * to which it is replying.
460 *
461 * [INIT ACK back to where the INIT came from.]
462 */
463 if (chunk)
464 retval->transport = chunk->transport;
465
466nomem_chunk:
467 kfree(cookie);
468nomem_cookie:
a51482bd 469 kfree(addrs.v);
1da177e4
LT		 470 return retval;
471}
472
473/* 3.3.11 Cookie Echo (COOKIE ECHO) (10):
474 *
475 * This chunk is used only during the initialization of an association.
476 * It is sent by the initiator of an association to its peer to complete
477 * the initialization process. This chunk MUST precede any DATA chunk
478 * sent within the association, but MAY be bundled with one or more DATA
479 * chunks in the same packet.
480 *
481 * 0 1 2 3
482 * 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
483 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
484 * | Type = 10 |Chunk Flags | Length |
485 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
486 * / Cookie /
487 * \ \
488 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
489 *
490 * Chunk Flags: 8 bit
491 *
492 * Set to zero on transmit and ignored on receipt.
493 *
494 * Length: 16 bits (unsigned integer)
495 *
496 * Set to the size of the chunk in bytes, including the 4 bytes of
497 * the chunk header and the size of the Cookie.
498 *
499 * Cookie: variable size
500 *
501 * This field must contain the exact cookie received in the
502 * State Cookie parameter from the previous INIT ACK.
503 *
504 * An implementation SHOULD make the cookie as small as possible
505 * to insure interoperability.
506 */
507struct sctp_chunk *sctp_make_cookie_echo(const struct sctp_association *asoc,
508 const struct sctp_chunk *chunk)
509{
510 struct sctp_chunk *retval;
511 void *cookie;
512 int cookie_len;
513
514 cookie = asoc->peer.cookie;
515 cookie_len = asoc->peer.cookie_len;
516
517 /* Build a cookie echo chunk. */
518 retval = sctp_make_chunk(asoc, SCTP_CID_COOKIE_ECHO, 0, cookie_len);
519 if (!retval)
520 goto nodata;
521 retval->subh.cookie_hdr =
522 sctp_addto_chunk(retval, cookie_len, cookie);
523
524 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
525 *
526 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
527 * HEARTBEAT ACK, * etc.) to the same destination transport
528 * address from which it * received the DATA or control chunk
529 * to which it is replying.
530 *
531 * [COOKIE ECHO back to where the INIT ACK came from.]
532 */
533 if (chunk)
534 retval->transport = chunk->transport;
535
536nodata:
537 return retval;
538}
539
540/* 3.3.12 Cookie Acknowledgement (COOKIE ACK) (11):
541 *
542 * This chunk is used only during the initialization of an
543 * association. It is used to acknowledge the receipt of a COOKIE
544 * ECHO chunk. This chunk MUST precede any DATA or SACK chunk sent
545 * within the association, but MAY be bundled with one or more DATA
546 * chunks or SACK chunk in the same SCTP packet.
547 *
548 * 0 1 2 3
549 * 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
550 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
551 * | Type = 11 |Chunk Flags | Length = 4 |
552 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
553 *
554 * Chunk Flags: 8 bits
555 *
556 * Set to zero on transmit and ignored on receipt.
557 */
558struct sctp_chunk *sctp_make_cookie_ack(const struct sctp_association *asoc,
559 const struct sctp_chunk *chunk)
560{
561 struct sctp_chunk *retval;
562
563 retval = sctp_make_chunk(asoc, SCTP_CID_COOKIE_ACK, 0, 0);
564
565 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
566 *
567 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
568 * HEARTBEAT ACK, * etc.) to the same destination transport
569 * address from which it * received the DATA or control chunk
570 * to which it is replying.
571 *
572 * [COOKIE ACK back to where the COOKIE ECHO came from.]
573 */
574 if (retval && chunk)
575 retval->transport = chunk->transport;
576
577 return retval;
578}
579
580/*
581 * Appendix A: Explicit Congestion Notification:
582 * CWR:
583 *
584 * RFC 2481 details a specific bit for a sender to send in the header of
585 * its next outbound TCP segment to indicate to its peer that it has
586 * reduced its congestion window. This is termed the CWR bit. For
587 * SCTP the same indication is made by including the CWR chunk.
588 * This chunk contains one data element, i.e. the TSN number that
589 * was sent in the ECNE chunk. This element represents the lowest
590 * TSN number in the datagram that was originally marked with the
591 * CE bit.
592 *
593 * 0 1 2 3
594 * 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
595 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
596 * | Chunk Type=13 | Flags=00000000| Chunk Length = 8 |
597 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
598 * | Lowest TSN Number |
599 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
600 *
601 * Note: The CWR is considered a Control chunk.
602 */
603struct sctp_chunk *sctp_make_cwr(const struct sctp_association *asoc,
604 const __u32 lowest_tsn,
605 const struct sctp_chunk *chunk)
606{
607 struct sctp_chunk *retval;
608 sctp_cwrhdr_t cwr;
609
610 cwr.lowest_tsn = htonl(lowest_tsn);
611 retval = sctp_make_chunk(asoc, SCTP_CID_ECN_CWR, 0,
612 sizeof(sctp_cwrhdr_t));
613
614 if (!retval)
615 goto nodata;
616
617 retval->subh.ecn_cwr_hdr =
618 sctp_addto_chunk(retval, sizeof(cwr), &cwr);
619
620 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
621 *
622 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
623 * HEARTBEAT ACK, * etc.) to the same destination transport
624 * address from which it * received the DATA or control chunk
625 * to which it is replying.
626 *
627 * [Report a reduced congestion window back to where the ECNE
628 * came from.]
629 */
630 if (chunk)
631 retval->transport = chunk->transport;
632
633nodata:
634 return retval;
635}
636
637/* Make an ECNE chunk. This is a congestion experienced report. */
638struct sctp_chunk *sctp_make_ecne(const struct sctp_association *asoc,
639 const __u32 lowest_tsn)
640{
641 struct sctp_chunk *retval;
642 sctp_ecnehdr_t ecne;
643
644 ecne.lowest_tsn = htonl(lowest_tsn);
645 retval = sctp_make_chunk(asoc, SCTP_CID_ECN_ECNE, 0,
646 sizeof(sctp_ecnehdr_t));
647 if (!retval)
648 goto nodata;
649 retval->subh.ecne_hdr =
650 sctp_addto_chunk(retval, sizeof(ecne), &ecne);
651
652nodata:
653 return retval;
654}
655
656/* Make a DATA chunk for the given association from the provided
657 * parameters. However, do not populate the data payload.
658 */
659struct sctp_chunk *sctp_make_datafrag_empty(struct sctp_association *asoc,
660 const struct sctp_sndrcvinfo *sinfo,
661 int data_len, __u8 flags, __u16 ssn)
662{
663 struct sctp_chunk *retval;
664 struct sctp_datahdr dp;
665 int chunk_len;
666
667 /* We assign the TSN as LATE as possible, not here when
668 * creating the chunk.
669 */
670 dp.tsn = 0;
671 dp.stream = htons(sinfo->sinfo_stream);
672 dp.ppid = sinfo->sinfo_ppid;
673
674 /* Set the flags for an unordered send. */
eaa5c54d 675 if (sinfo->sinfo_flags & SCTP_UNORDERED) {
1da177e4
LT		 676 flags |= SCTP_DATA_UNORDERED;
677 dp.ssn = 0;
678 } else
679 dp.ssn = htons(ssn);
680
681 chunk_len = sizeof(dp) + data_len;
682 retval = sctp_make_chunk(asoc, SCTP_CID_DATA, flags, chunk_len);
683 if (!retval)
684 goto nodata;
685
686 retval->subh.data_hdr = sctp_addto_chunk(retval, sizeof(dp), &dp);
687 memcpy(&retval->sinfo, sinfo, sizeof(struct sctp_sndrcvinfo));
688
689nodata:
690 return retval;
691}
692
693/* Create a selective ackowledgement (SACK) for the given
694 * association. This reports on which TSN's we've seen to date,
695 * including duplicates and gaps.
696 */
697struct sctp_chunk *sctp_make_sack(const struct sctp_association *asoc)
698{
699 struct sctp_chunk *retval;
700 struct sctp_sackhdr sack;
701 int len;
702 __u32 ctsn;
703 __u16 num_gabs, num_dup_tsns;
704 struct sctp_tsnmap *map = (struct sctp_tsnmap *)&asoc->peer.tsn_map;
02015180 705 struct sctp_gap_ack_block gabs[SCTP_MAX_GABS];
1da177e4 706
02015180 707 memset(gabs, 0, sizeof(gabs));
1da177e4
LT		 708 ctsn = sctp_tsnmap_get_ctsn(map);
709 SCTP_DEBUG_PRINTK("sackCTSNAck sent: 0x%x.\n", ctsn);
710
711 /* How much room is needed in the chunk? */
02015180 712 num_gabs = sctp_tsnmap_num_gabs(map, gabs);
1da177e4
LT		 713 num_dup_tsns = sctp_tsnmap_num_dups(map);
714
715 /* Initialize the SACK header. */
716 sack.cum_tsn_ack = htonl(ctsn);
717 sack.a_rwnd = htonl(asoc->a_rwnd);
718 sack.num_gap_ack_blocks = htons(num_gabs);
719 sack.num_dup_tsns = htons(num_dup_tsns);
720
721 len = sizeof(sack)
722 + sizeof(struct sctp_gap_ack_block) * num_gabs
723 + sizeof(__u32) * num_dup_tsns;
724
725 /* Create the chunk. */
726 retval = sctp_make_chunk(asoc, SCTP_CID_SACK, 0, len);
727 if (!retval)
728 goto nodata;
729
730 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
731 *
732 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
733 * HEARTBEAT ACK, etc.) to the same destination transport
734 * address from which it received the DATA or control chunk to
735 * which it is replying. This rule should also be followed if
736 * the endpoint is bundling DATA chunks together with the
737 * reply chunk.
738 *
739 * However, when acknowledging multiple DATA chunks received
740 * in packets from different source addresses in a single
741 * SACK, the SACK chunk may be transmitted to one of the
742 * destination transport addresses from which the DATA or
743 * control chunks being acknowledged were received.
744 *
745 * [BUG: We do not implement the following paragraph.
746 * Perhaps we should remember the last transport we used for a
747 * SACK and avoid that (if possible) if we have seen any
748 * duplicates. --piggy]
749 *
750 * When a receiver of a duplicate DATA chunk sends a SACK to a
751 * multi- homed endpoint it MAY be beneficial to vary the
752 * destination address and not use the source address of the
753 * DATA chunk. The reason being that receiving a duplicate
754 * from a multi-homed endpoint might indicate that the return
755 * path (as specified in the source address of the DATA chunk)
756 * for the SACK is broken.
757 *
758 * [Send to the address from which we last received a DATA chunk.]
759 */
760 retval->transport = asoc->peer.last_data_from;
761
762 retval->subh.sack_hdr =
763 sctp_addto_chunk(retval, sizeof(sack), &sack);
764
765 /* Add the gap ack block information. */
766 if (num_gabs)
767 sctp_addto_chunk(retval, sizeof(__u32) * num_gabs,
02015180 768 gabs);
1da177e4
LT		 769
770 /* Add the duplicate TSN information. */
771 if (num_dup_tsns)
772 sctp_addto_chunk(retval, sizeof(__u32) * num_dup_tsns,
773 sctp_tsnmap_get_dups(map));
774
775nodata:
776 return retval;
777}
778
779/* Make a SHUTDOWN chunk. */
780struct sctp_chunk *sctp_make_shutdown(const struct sctp_association *asoc,
781 const struct sctp_chunk *chunk)
782{
783 struct sctp_chunk *retval;
784 sctp_shutdownhdr_t shut;
785 __u32 ctsn;
786
787 ctsn = sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map);
788 shut.cum_tsn_ack = htonl(ctsn);
789
790 retval = sctp_make_chunk(asoc, SCTP_CID_SHUTDOWN, 0,
791 sizeof(sctp_shutdownhdr_t));
792 if (!retval)
793 goto nodata;
794
795 retval->subh.shutdown_hdr =
796 sctp_addto_chunk(retval, sizeof(shut), &shut);
797
798 if (chunk)
799 retval->transport = chunk->transport;
800nodata:
801 return retval;
802}
803
804struct sctp_chunk *sctp_make_shutdown_ack(const struct sctp_association *asoc,
805 const struct sctp_chunk *chunk)
806{
807 struct sctp_chunk *retval;
808
809 retval = sctp_make_chunk(asoc, SCTP_CID_SHUTDOWN_ACK, 0, 0);
810
811 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
812 *
813 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
814 * HEARTBEAT ACK, * etc.) to the same destination transport
815 * address from which it * received the DATA or control chunk
816 * to which it is replying.
817 *
818 * [ACK back to where the SHUTDOWN came from.]
819 */
820 if (retval && chunk)
821 retval->transport = chunk->transport;
822
823 return retval;
824}
825
826struct sctp_chunk *sctp_make_shutdown_complete(
827 const struct sctp_association *asoc,
828 const struct sctp_chunk *chunk)
829{
830 struct sctp_chunk *retval;
831 __u8 flags = 0;
832
047a2428
JF		 833 /* Set the T-bit if we have no association (vtag will be
834 * reflected)
835 */
1da177e4
LT		 836 flags |= asoc ? 0 : SCTP_CHUNK_FLAG_T;
837
838 retval = sctp_make_chunk(asoc, SCTP_CID_SHUTDOWN_COMPLETE, flags, 0);
839
840 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
841 *
842 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
843 * HEARTBEAT ACK, * etc.) to the same destination transport
844 * address from which it * received the DATA or control chunk
845 * to which it is replying.
846 *
847 * [Report SHUTDOWN COMPLETE back to where the SHUTDOWN ACK
848 * came from.]
849 */
850 if (retval && chunk)
851 retval->transport = chunk->transport;
852
d808ad9a 853 return retval;
1da177e4
LT		 854}
855
856/* Create an ABORT. Note that we set the T bit if we have no
047a2428 857 * association, except when responding to an INIT (sctpimpguide 2.41).
1da177e4
LT		 858 */
859struct sctp_chunk *sctp_make_abort(const struct sctp_association *asoc,
860 const struct sctp_chunk *chunk,
861 const size_t hint)
862{
863 struct sctp_chunk *retval;
864 __u8 flags = 0;
865
047a2428
JF		 866 /* Set the T-bit if we have no association and 'chunk' is not
867 * an INIT (vtag will be reflected).
868 */
869 if (!asoc) {
870 if (chunk && chunk->chunk_hdr &&
871 chunk->chunk_hdr->type == SCTP_CID_INIT)
872 flags = 0;
873 else
874 flags = SCTP_CHUNK_FLAG_T;
875 }
1da177e4
LT		 876
877 retval = sctp_make_chunk(asoc, SCTP_CID_ABORT, flags, hint);
878
879 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
880 *
881 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
882 * HEARTBEAT ACK, * etc.) to the same destination transport
883 * address from which it * received the DATA or control chunk
884 * to which it is replying.
885 *
886 * [ABORT back to where the offender came from.]
887 */
888 if (retval && chunk)
889 retval->transport = chunk->transport;
890
891 return retval;
892}
893
894/* Helper to create ABORT with a NO_USER_DATA error. */
895struct sctp_chunk *sctp_make_abort_no_data(
896 const struct sctp_association *asoc,
897 const struct sctp_chunk *chunk, __u32 tsn)
898{
899 struct sctp_chunk *retval;
9f81bcd9 900 __be32 payload;
1da177e4
LT		 901
902 retval = sctp_make_abort(asoc, chunk, sizeof(sctp_errhdr_t)
903 + sizeof(tsn));
904
905 if (!retval)
906 goto no_mem;
907
908 /* Put the tsn back into network byte order. */
909 payload = htonl(tsn);
00f1c2df
WY		 910 sctp_init_cause(retval, SCTP_ERROR_NO_DATA, sizeof(payload));
911 sctp_addto_chunk(retval, sizeof(payload), (const void *)&payload);
1da177e4
LT		 912
913 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
914 *
915 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
916 * HEARTBEAT ACK, * etc.) to the same destination transport
917 * address from which it * received the DATA or control chunk
918 * to which it is replying.
919 *
920 * [ABORT back to where the offender came from.]
921 */
922 if (chunk)
923 retval->transport = chunk->transport;
924
925no_mem:
926 return retval;
927}
928
929/* Helper to create ABORT with a SCTP_ERROR_USER_ABORT error. */
930struct sctp_chunk *sctp_make_abort_user(const struct sctp_association *asoc,
c164a9ba
SS		 931 const struct msghdr *msg,
932 size_t paylen)
1da177e4
LT		 933{
934 struct sctp_chunk *retval;
c164a9ba
SS		 935 void *payload = NULL;
936 int err;
1da177e4 937
c164a9ba 938 retval = sctp_make_abort(asoc, NULL, sizeof(sctp_errhdr_t) + paylen);
1da177e4
LT		 939 if (!retval)
940 goto err_chunk;
941
942 if (paylen) {
943 /* Put the msg_iov together into payload. */
c164a9ba 944 payload = kmalloc(paylen, GFP_KERNEL);
1da177e4
LT		 945 if (!payload)
946 goto err_payload;
c164a9ba
SS		 947
948 err = memcpy_fromiovec(payload, msg->msg_iov, paylen);
949 if (err < 0)
950 goto err_copy;
1da177e4
LT		 951 }
952
00f1c2df
WY		 953 sctp_init_cause(retval, SCTP_ERROR_USER_ABORT, paylen);
954 sctp_addto_chunk(retval, paylen, payload);
1da177e4
LT		 955
956 if (paylen)
957 kfree(payload);
958
959 return retval;
960
961err_copy:
962 kfree(payload);
963err_payload:
964 sctp_chunk_free(retval);
965 retval = NULL;
966err_chunk:
967 return retval;
968}
969
5c94bf86
AB		 970/* Append bytes to the end of a parameter. Will panic if chunk is not big
971 * enough.
972 */
973static void *sctp_addto_param(struct sctp_chunk *chunk, int len,
974 const void *data)
975{
976 void *target;
977 int chunklen = ntohs(chunk->chunk_hdr->length);
978
979 target = skb_put(chunk->skb, len);
980
981 memcpy(target, data, len);
982
983 /* Adjust the chunk length field. */
984 chunk->chunk_hdr->length = htons(chunklen + len);
985 chunk->chunk_end = skb_tail_pointer(chunk->skb);
986
987 return target;
988}
989
d808ad9a 990/* Make an ABORT chunk with a PROTOCOL VIOLATION cause code. */
1da177e4
LT		 991struct sctp_chunk *sctp_make_abort_violation(
992 const struct sctp_association *asoc,
993 const struct sctp_chunk *chunk,
994 const __u8 *payload,
995 const size_t paylen)
996{
997 struct sctp_chunk *retval;
998 struct sctp_paramhdr phdr;
999
1000 retval = sctp_make_abort(asoc, chunk, sizeof(sctp_errhdr_t) + paylen
00f1c2df 1001 + sizeof(sctp_paramhdr_t));
1da177e4
LT		 1002 if (!retval)
1003 goto end;
1004
00f1c2df
WY		 1005 sctp_init_cause(retval, SCTP_ERROR_PROTO_VIOLATION, paylen
1006 + sizeof(sctp_paramhdr_t));
1da177e4
LT		 1007
1008 phdr.type = htons(chunk->chunk_hdr->type);
1009 phdr.length = chunk->chunk_hdr->length;
00f1c2df
WY		 1010 sctp_addto_chunk(retval, paylen, payload);
1011 sctp_addto_param(retval, sizeof(sctp_paramhdr_t), &phdr);
1da177e4
LT		 1012
1013end:
1014 return retval;
1015}
1016
ba016670
WY		 1017struct sctp_chunk *sctp_make_violation_paramlen(
1018 const struct sctp_association *asoc,
1019 const struct sctp_chunk *chunk,
1020 struct sctp_paramhdr *param)
1021{
1022 struct sctp_chunk *retval;
1023 static const char error[] = "The following parameter had invalid length:";
1024 size_t payload_len = sizeof(error) + sizeof(sctp_errhdr_t) +
1025 sizeof(sctp_paramhdr_t);
1026
1027 retval = sctp_make_abort(asoc, chunk, payload_len);
1028 if (!retval)
1029 goto nodata;
1030
1031 sctp_init_cause(retval, SCTP_ERROR_PROTO_VIOLATION,
1032 sizeof(error) + sizeof(sctp_paramhdr_t));
1033 sctp_addto_chunk(retval, sizeof(error), error);
1034 sctp_addto_param(retval, sizeof(sctp_paramhdr_t), param);
1035
1036nodata:
1037 return retval;
1038}
1039
1da177e4
LT		 1040/* Make a HEARTBEAT chunk. */
1041struct sctp_chunk *sctp_make_heartbeat(const struct sctp_association *asoc,
1042 const struct sctp_transport *transport,
1043 const void *payload, const size_t paylen)
1044{
1045 struct sctp_chunk *retval = sctp_make_chunk(asoc, SCTP_CID_HEARTBEAT,
1046 0, paylen);
1047
1048 if (!retval)
1049 goto nodata;
1050
1051 /* Cast away the 'const', as this is just telling the chunk
1052 * what transport it belongs to.
1053 */
1054 retval->transport = (struct sctp_transport *) transport;
1055 retval->subh.hbs_hdr = sctp_addto_chunk(retval, paylen, payload);
1056
1057nodata:
1058 return retval;
1059}
1060
1061struct sctp_chunk *sctp_make_heartbeat_ack(const struct sctp_association *asoc,
1062 const struct sctp_chunk *chunk,
1063 const void *payload, const size_t paylen)
1064{
1065 struct sctp_chunk *retval;
1066
1067 retval = sctp_make_chunk(asoc, SCTP_CID_HEARTBEAT_ACK, 0, paylen);
1068 if (!retval)
1069 goto nodata;
1070
1071 retval->subh.hbs_hdr = sctp_addto_chunk(retval, paylen, payload);
1072
1073 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
1074 *
1075 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
1076 * HEARTBEAT ACK, * etc.) to the same destination transport
1077 * address from which it * received the DATA or control chunk
1078 * to which it is replying.
1079 *
1080 * [HBACK back to where the HEARTBEAT came from.]
1081 */
1082 if (chunk)
1083 retval->transport = chunk->transport;
1084
1085nodata:
1086 return retval;
1087}
1088
1089/* Create an Operation Error chunk with the specified space reserved.
1090 * This routine can be used for containing multiple causes in the chunk.
1091 */
1092static struct sctp_chunk *sctp_make_op_error_space(
1093 const struct sctp_association *asoc,
1094 const struct sctp_chunk *chunk,
1095 size_t size)
1096{
1097 struct sctp_chunk *retval;
1098
1099 retval = sctp_make_chunk(asoc, SCTP_CID_ERROR, 0,
1100 sizeof(sctp_errhdr_t) + size);
1101 if (!retval)
1102 goto nodata;
1103
1104 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
1105 *
1106 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
1107 * HEARTBEAT ACK, etc.) to the same destination transport
1108 * address from which it received the DATA or control chunk
1109 * to which it is replying.
1110 *
1111 */
1112 if (chunk)
1113 retval->transport = chunk->transport;
1114
1115nodata:
1116 return retval;
1117}
1118
1119/* Create an Operation Error chunk. */
1120struct sctp_chunk *sctp_make_op_error(const struct sctp_association *asoc,
1121 const struct sctp_chunk *chunk,
63706c5c 1122 __be16 cause_code, const void *payload,
1da177e4
LT		 1123 size_t paylen)
1124{
1125 struct sctp_chunk *retval;
1126
1127 retval = sctp_make_op_error_space(asoc, chunk, paylen);
1128 if (!retval)
1129 goto nodata;
1130
00f1c2df
WY		 1131 sctp_init_cause(retval, cause_code, paylen);
1132 sctp_addto_chunk(retval, paylen, payload);
1da177e4
LT		 1133
1134nodata:
1135 return retval;
1136}
1137
4cd57c80
VY		 1138struct sctp_chunk *sctp_make_auth(const struct sctp_association *asoc)
1139{
1140 struct sctp_chunk *retval;
1141 struct sctp_hmac *hmac_desc;
1142 struct sctp_authhdr auth_hdr;
1143 __u8 *hmac;
1144
1145 /* Get the first hmac that the peer told us to use */
1146 hmac_desc = sctp_auth_asoc_get_hmac(asoc);
1147 if (unlikely(!hmac_desc))
1148 return NULL;
1149
1150 retval = sctp_make_chunk(asoc, SCTP_CID_AUTH, 0,
1151 hmac_desc->hmac_len + sizeof(sctp_authhdr_t));
1152 if (!retval)
1153 return NULL;
1154
1155 auth_hdr.hmac_id = htons(hmac_desc->hmac_id);
1156 auth_hdr.shkey_id = htons(asoc->active_key_id);
1157
1158 retval->subh.auth_hdr = sctp_addto_chunk(retval, sizeof(sctp_authhdr_t),
1159 &auth_hdr);
1160
1161 hmac = skb_put(retval->skb, hmac_desc->hmac_len);
1162 memset(hmac, 0, hmac_desc->hmac_len);
1163
1164 /* Adjust the chunk header to include the empty MAC */
1165 retval->chunk_hdr->length =
1166 htons(ntohs(retval->chunk_hdr->length) + hmac_desc->hmac_len);
1167 retval->chunk_end = skb_tail_pointer(retval->skb);
1168
1169 return retval;
1170}
1171
1172
1da177e4
LT		 1173/********************************************************************
1174 * 2nd Level Abstractions
1175 ********************************************************************/
1176
1177/* Turn an skb into a chunk.
1178 * FIXME: Eventually move the structure directly inside the skb->cb[].
1179 */
1180struct sctp_chunk *sctp_chunkify(struct sk_buff *skb,
1181 const struct sctp_association *asoc,
1182 struct sock *sk)
1183{
1184 struct sctp_chunk *retval;
1185
c3762229 1186 retval = kmem_cache_zalloc(sctp_chunk_cachep, GFP_ATOMIC);
1da177e4
LT		 1187
1188 if (!retval)
1189 goto nodata;
1da177e4
LT		 1190
1191 if (!sk) {
1192 SCTP_DEBUG_PRINTK("chunkifying skb %p w/o an sk\n", skb);
1193 }
1194
79af02c2 1195 INIT_LIST_HEAD(&retval->list);
1da177e4
LT		 1196 retval->skb = skb;
1197 retval->asoc = (struct sctp_association *)asoc;
1198 retval->resent = 0;
1199 retval->has_tsn = 0;
1200 retval->has_ssn = 0;
1201 retval->rtt_in_progress = 0;
1202 retval->sent_at = 0;
1203 retval->singleton = 1;
1204 retval->end_of_packet = 0;
1205 retval->ecn_ce_done = 0;
1206 retval->pdiscard = 0;
1207
1208 /* sctpimpguide-05.txt Section 2.8.2
1209 * M1) Each time a new DATA chunk is transmitted
1210 * set the 'TSN.Missing.Report' count for that TSN to 0. The
1211 * 'TSN.Missing.Report' count will be used to determine missing chunks
1212 * and when to fast retransmit.
1213 */
1214 retval->tsn_missing_report = 0;
1215 retval->tsn_gap_acked = 0;
c226ef9b 1216 retval->fast_retransmit = SCTP_CAN_FRTX;
1da177e4
LT		 1217
1218 /* If this is a fragmented message, track all fragments
1219 * of the message (for SEND_FAILED).
1220 */
1221 retval->msg = NULL;
1222
1223 /* Polish the bead hole. */
1224 INIT_LIST_HEAD(&retval->transmitted_list);
1225 INIT_LIST_HEAD(&retval->frag_list);
1226 SCTP_DBG_OBJCNT_INC(chunk);
1227 atomic_set(&retval->refcnt, 1);
1228
1229nodata:
1230 return retval;
1231}
1232
1233/* Set chunk->source and dest based on the IP header in chunk->skb. */
1234void sctp_init_addrs(struct sctp_chunk *chunk, union sctp_addr *src,
1235 union sctp_addr *dest)
1236{
f235fca3 1237 memcpy(&chunk->source, src, sizeof(union sctp_addr));
16b0a030 1238 memcpy(&chunk->dest, dest, sizeof(union sctp_addr));
1da177e4
LT		 1239}
1240
1241/* Extract the source address from a chunk. */
1242const union sctp_addr *sctp_source(const struct sctp_chunk *chunk)
1243{
1244 /* If we have a known transport, use that. */
1245 if (chunk->transport) {
6a1e5f33 1246 return &chunk->transport->ipaddr;
1da177e4
LT		 1247 } else {
1248 /* Otherwise, extract it from the IP header. */
6a1e5f33 1249 return &chunk->source;
1da177e4
LT		 1250 }
1251}
1252
1253/* Create a new chunk, setting the type and flags headers from the
1254 * arguments, reserving enough space for a 'paylen' byte payload.
1255 */
1256SCTP_STATIC
1257struct sctp_chunk *sctp_make_chunk(const struct sctp_association *asoc,
1258 __u8 type, __u8 flags, int paylen)
1259{
1260 struct sctp_chunk *retval;
1261 sctp_chunkhdr_t *chunk_hdr;
1262 struct sk_buff *skb;
1263 struct sock *sk;
1264
1265 /* No need to allocate LL here, as this is only a chunk. */
1266 skb = alloc_skb(WORD_ROUND(sizeof(sctp_chunkhdr_t) + paylen),
1267 GFP_ATOMIC);
1268 if (!skb)
1269 goto nodata;
1270
1271 /* Make room for the chunk header. */
1272 chunk_hdr = (sctp_chunkhdr_t *)skb_put(skb, sizeof(sctp_chunkhdr_t));
1273 chunk_hdr->type = type;
1274 chunk_hdr->flags = flags;
1275 chunk_hdr->length = htons(sizeof(sctp_chunkhdr_t));
1276
1277 sk = asoc ? asoc->base.sk : NULL;
1278 retval = sctp_chunkify(skb, asoc, sk);
1279 if (!retval) {
1280 kfree_skb(skb);
1281 goto nodata;
1282 }
1283
1284 retval->chunk_hdr = chunk_hdr;
1285 retval->chunk_end = ((__u8 *)chunk_hdr) + sizeof(struct sctp_chunkhdr);
1286
4cd57c80
VY		 1287 /* Determine if the chunk needs to be authenticated */
1288 if (sctp_auth_send_cid(type, asoc))
1289 retval->auth = 1;
1290
1da177e4
LT		 1291 /* Set the skb to the belonging sock for accounting. */
1292 skb->sk = sk;
1293
1294 return retval;
1295nodata:
1296 return NULL;
1297}
1298
1299
1300/* Release the memory occupied by a chunk. */
1301static void sctp_chunk_destroy(struct sctp_chunk *chunk)
1302{
a08de64d
VY		 1303 BUG_ON(!list_empty(&chunk->list));
1304 list_del_init(&chunk->transmitted_list);
1305
1da177e4
LT		 1306 /* Free the chunk skb data and the SCTP_chunk stub itself. */
1307 dev_kfree_skb(chunk->skb);
1308
1309 SCTP_DBG_OBJCNT_DEC(chunk);
1310 kmem_cache_free(sctp_chunk_cachep, chunk);
1311}
1312
1313/* Possibly, free the chunk. */
1314void sctp_chunk_free(struct sctp_chunk *chunk)
1315{
1da177e4
LT		 1316 /* Release our reference on the message tracker. */
1317 if (chunk->msg)
1318 sctp_datamsg_put(chunk->msg);
1319
1320 sctp_chunk_put(chunk);
1321}
1322
1323/* Grab a reference to the chunk. */
1324void sctp_chunk_hold(struct sctp_chunk *ch)
1325{
1326 atomic_inc(&ch->refcnt);
1327}
1328
1329/* Release a reference to the chunk. */
1330void sctp_chunk_put(struct sctp_chunk *ch)
1331{
1332 if (atomic_dec_and_test(&ch->refcnt))
1333 sctp_chunk_destroy(ch);
1334}
1335
1336/* Append bytes to the end of a chunk. Will panic if chunk is not big
1337 * enough.
1338 */
1339void *sctp_addto_chunk(struct sctp_chunk *chunk, int len, const void *data)
1340{
1341 void *target;
1342 void *padding;
1343 int chunklen = ntohs(chunk->chunk_hdr->length);
8d614ade 1344 int padlen = WORD_ROUND(chunklen) - chunklen;
1da177e4
LT		 1345
1346 padding = skb_put(chunk->skb, padlen);
1347 target = skb_put(chunk->skb, len);
1348
1349 memset(padding, 0, padlen);
1350 memcpy(target, data, len);
1351
1352 /* Adjust the chunk length field. */
1353 chunk->chunk_hdr->length = htons(chunklen + padlen + len);
27a884dc 1354 chunk->chunk_end = skb_tail_pointer(chunk->skb);
1da177e4
LT		 1355
1356 return target;
1357}
1358
1359/* Append bytes from user space to the end of a chunk. Will panic if
1360 * chunk is not big enough.
1361 * Returns a kernel err value.
1362 */
1363int sctp_user_addto_chunk(struct sctp_chunk *chunk, int off, int len,
1364 struct iovec *data)
1365{
1366 __u8 *target;
1367 int err = 0;
1368
1369 /* Make room in chunk for data. */
1370 target = skb_put(chunk->skb, len);
1371
1372 /* Copy data (whole iovec) into chunk */
1373 if ((err = memcpy_fromiovecend(target, data, off, len)))
1374 goto out;
1375
1376 /* Adjust the chunk length field. */
1377 chunk->chunk_hdr->length =
1378 htons(ntohs(chunk->chunk_hdr->length) + len);
27a884dc 1379 chunk->chunk_end = skb_tail_pointer(chunk->skb);
1da177e4
LT		 1380
1381out:
1382 return err;
1383}
1384
1385/* Helper function to assign a TSN if needed. This assumes that both
1386 * the data_hdr and association have already been assigned.
1387 */
1388void sctp_chunk_assign_ssn(struct sctp_chunk *chunk)
1389{
ab3e5e7b
VY		 1390 struct sctp_datamsg *msg;
1391 struct sctp_chunk *lchunk;
1392 struct sctp_stream *stream;
1da177e4
LT		 1393 __u16 ssn;
1394 __u16 sid;
1395
1396 if (chunk->has_ssn)
1397 return;
1398
ab3e5e7b
VY		 1399 /* All fragments will be on the same stream */
1400 sid = ntohs(chunk->subh.data_hdr->stream);
1401 stream = &chunk->asoc->ssnmap->out;
1da177e4 1402
ab3e5e7b
VY		 1403 /* Now assign the sequence number to the entire message.
1404 * All fragments must have the same stream sequence number.
1405 */
1406 msg = chunk->msg;
1407 list_for_each_entry(lchunk, &msg->chunks, frag_list) {
1408 if (lchunk->chunk_hdr->flags & SCTP_DATA_UNORDERED) {
1409 ssn = 0;
1410 } else {
1411 if (lchunk->chunk_hdr->flags & SCTP_DATA_LAST_FRAG)
1412 ssn = sctp_ssn_next(stream, sid);
1413 else
1414 ssn = sctp_ssn_peek(stream, sid);
1415 }
1416
1417 lchunk->subh.data_hdr->ssn = htons(ssn);
1418 lchunk->has_ssn = 1;
1419 }
1da177e4
LT		 1420}
1421
1422/* Helper function to assign a TSN if needed. This assumes that both
1423 * the data_hdr and association have already been assigned.
1424 */
1425void sctp_chunk_assign_tsn(struct sctp_chunk *chunk)
1426{
1427 if (!chunk->has_tsn) {
1428 /* This is the last possible instant to
1429 * assign a TSN.
1430 */
1431 chunk->subh.data_hdr->tsn =
1432 htonl(sctp_association_get_next_tsn(chunk->asoc));
1433 chunk->has_tsn = 1;
1434 }
1435}
1436
1437/* Create a CLOSED association to use with an incoming packet. */
1438struct sctp_association *sctp_make_temp_asoc(const struct sctp_endpoint *ep,
3182cd84 1439 struct sctp_chunk *chunk,
dd0fc66f 1440 gfp_t gfp)
1da177e4
LT		 1441{
1442 struct sctp_association *asoc;
1443 struct sk_buff *skb;
1444 sctp_scope_t scope;
1445 struct sctp_af *af;
1446
1447 /* Create the bare association. */
1448 scope = sctp_scope(sctp_source(chunk));
1449 asoc = sctp_association_new(ep, ep->base.sk, scope, gfp);
1450 if (!asoc)
1451 goto nodata;
1452 asoc->temp = 1;
1453 skb = chunk->skb;
1454 /* Create an entry for the source address of the packet. */
eddc9ec5 1455 af = sctp_get_af_specific(ipver2af(ip_hdr(skb)->version));
1da177e4
LT		 1456 if (unlikely(!af))
1457 goto fail;
d55c41b1 1458 af->from_skb(&asoc->c.peer_addr, skb, 1);
1da177e4
LT		 1459nodata:
1460 return asoc;
1461
1462fail:
1463 sctp_association_free(asoc);
1464 return NULL;
1465}
1466
1467/* Build a cookie representing asoc.
1468 * This INCLUDES the param header needed to put the cookie in the INIT ACK.
1469 */
1470static sctp_cookie_param_t *sctp_pack_cookie(const struct sctp_endpoint *ep,
1471 const struct sctp_association *asoc,
1472 const struct sctp_chunk *init_chunk,
1473 int *cookie_len,
1474 const __u8 *raw_addrs, int addrs_len)
1475{
1476 sctp_cookie_param_t *retval;
1477 struct sctp_signed_cookie *cookie;
1478 struct scatterlist sg;
1479 int headersize, bodysize;
1480 unsigned int keylen;
1481 char *key;
1482
9834a2bb
VY		 1483 /* Header size is static data prior to the actual cookie, including
1484 * any padding.
1485 */
d808ad9a
YH		 1486 headersize = sizeof(sctp_paramhdr_t) +
1487 (sizeof(struct sctp_signed_cookie) -
9834a2bb 1488 sizeof(struct sctp_cookie));
1da177e4
LT		 1489 bodysize = sizeof(struct sctp_cookie)
1490 + ntohs(init_chunk->chunk_hdr->length) + addrs_len;
1491
1492 /* Pad out the cookie to a multiple to make the signature
1493 * functions simpler to write.
1494 */
1495 if (bodysize % SCTP_COOKIE_MULTIPLE)
1496 bodysize += SCTP_COOKIE_MULTIPLE
1497 - (bodysize % SCTP_COOKIE_MULTIPLE);
1498 *cookie_len = headersize + bodysize;
1499
1da177e4
LT		 1500 /* Clear this memory since we are sending this data structure
1501 * out on the network.
1502 */
af997d8c
ACM		 1503 retval = kzalloc(*cookie_len, GFP_ATOMIC);
1504 if (!retval)
1505 goto nodata;
1506
1da177e4
LT		 1507 cookie = (struct sctp_signed_cookie *) retval->body;
1508
1509 /* Set up the parameter header. */
1510 retval->p.type = SCTP_PARAM_STATE_COOKIE;
1511 retval->p.length = htons(*cookie_len);
1512
1513 /* Copy the cookie part of the association itself. */
1514 cookie->c = asoc->c;
1515 /* Save the raw address list length in the cookie. */
1516 cookie->c.raw_addr_list_len = addrs_len;
1517
1518 /* Remember PR-SCTP capability. */
1519 cookie->c.prsctp_capable = asoc->peer.prsctp_capable;
1520
0f3fffd8
ISJ		 1521 /* Save adaptation indication in the cookie. */
1522 cookie->c.adaptation_ind = asoc->peer.adaptation_ind;
1da177e4
LT		 1523
1524 /* Set an expiration time for the cookie. */
1525 do_gettimeofday(&cookie->c.expiration);
1526 TIMEVAL_ADD(asoc->cookie_life, cookie->c.expiration);
1527
1528 /* Copy the peer's init packet. */
1529 memcpy(&cookie->c.peer_init[0], init_chunk->chunk_hdr,
1530 ntohs(init_chunk->chunk_hdr->length));
1531
1532 /* Copy the raw local address list of the association. */
1533 memcpy((__u8 *)&cookie->c.peer_init[0] +
1534 ntohs(init_chunk->chunk_hdr->length), raw_addrs, addrs_len);
1535
d808ad9a 1536 if (sctp_sk(ep->base.sk)->hmac) {
1b489e11
HX		 1537 struct hash_desc desc;
1538
1da177e4 1539 /* Sign the message. */
68e3f5dd 1540 sg_init_one(&sg, &cookie->c, bodysize);
1da177e4
LT		 1541 keylen = SCTP_SECRET_SIZE;
1542 key = (char *)ep->secret_key[ep->current_key];
d808ad9a
YH		 1543 desc.tfm = sctp_sk(ep->base.sk)->hmac;
1544 desc.flags = 0;
1da177e4 1545
1b489e11
HX		 1546 if (crypto_hash_setkey(desc.tfm, key, keylen) ||
1547 crypto_hash_digest(&desc, &sg, bodysize, cookie->signature))
1548 goto free_cookie;
1da177e4
LT		 1549 }
1550
1da177e4 1551 return retval;
1b489e11
HX		 1552
1553free_cookie:
1554 kfree(retval);
1555nodata:
1556 *cookie_len = 0;
1557 return NULL;
1da177e4
LT		 1558}
1559
1560/* Unpack the cookie from COOKIE ECHO chunk, recreating the association. */
1561struct sctp_association *sctp_unpack_cookie(
1562 const struct sctp_endpoint *ep,
1563 const struct sctp_association *asoc,
dd0fc66f 1564 struct sctp_chunk *chunk, gfp_t gfp,
1da177e4
LT		 1565 int *error, struct sctp_chunk **errp)
1566{
1567 struct sctp_association *retval = NULL;
1568 struct sctp_signed_cookie *cookie;
1569 struct sctp_cookie *bear_cookie;
1570 int headersize, bodysize, fixed_size;
313e7b4d 1571 __u8 *digest = ep->digest;
1da177e4
LT		 1572 struct scatterlist sg;
1573 unsigned int keylen, len;
1574 char *key;
1575 sctp_scope_t scope;
1576 struct sk_buff *skb = chunk->skb;
a61bbcf2 1577 struct timeval tv;
1b489e11 1578 struct hash_desc desc;
1da177e4 1579
9834a2bb
VY		 1580 /* Header size is static data prior to the actual cookie, including
1581 * any padding.
1582 */
1583 headersize = sizeof(sctp_chunkhdr_t) +
d808ad9a 1584 (sizeof(struct sctp_signed_cookie) -
9834a2bb 1585 sizeof(struct sctp_cookie));
1da177e4
LT		 1586 bodysize = ntohs(chunk->chunk_hdr->length) - headersize;
1587 fixed_size = headersize + sizeof(struct sctp_cookie);
1588
1589 /* Verify that the chunk looks like it even has a cookie.
1590 * There must be enough room for our cookie and our peer's
1591 * INIT chunk.
1592 */
1593 len = ntohs(chunk->chunk_hdr->length);
1594 if (len < fixed_size + sizeof(struct sctp_chunkhdr))
1595 goto malformed;
1596
1597 /* Verify that the cookie has been padded out. */
1598 if (bodysize % SCTP_COOKIE_MULTIPLE)
1599 goto malformed;
1600
1601 /* Process the cookie. */
1602 cookie = chunk->subh.cookie_hdr;
1603 bear_cookie = &cookie->c;
1604
1605 if (!sctp_sk(ep->base.sk)->hmac)
1606 goto no_hmac;
1607
1608 /* Check the signature. */
1609 keylen = SCTP_SECRET_SIZE;
68e3f5dd 1610 sg_init_one(&sg, bear_cookie, bodysize);
1da177e4 1611 key = (char *)ep->secret_key[ep->current_key];
1b489e11
HX		 1612 desc.tfm = sctp_sk(ep->base.sk)->hmac;
1613 desc.flags = 0;
1da177e4 1614
8ca84481 1615 memset(digest, 0x00, SCTP_SIGNATURE_SIZE);
1b489e11
HX		 1616 if (crypto_hash_setkey(desc.tfm, key, keylen) ||
1617 crypto_hash_digest(&desc, &sg, bodysize, digest)) {
1618 *error = -SCTP_IERROR_NOMEM;
1619 goto fail;
1620 }
1da177e4
LT		 1621
1622 if (memcmp(digest, cookie->signature, SCTP_SIGNATURE_SIZE)) {
1623 /* Try the previous key. */
1624 key = (char *)ep->secret_key[ep->last_key];
8ca84481 1625 memset(digest, 0x00, SCTP_SIGNATURE_SIZE);
1b489e11
HX		 1626 if (crypto_hash_setkey(desc.tfm, key, keylen) ||
1627 crypto_hash_digest(&desc, &sg, bodysize, digest)) {
1628 *error = -SCTP_IERROR_NOMEM;
1629 goto fail;
1630 }
1da177e4
LT		 1631
1632 if (memcmp(digest, cookie->signature, SCTP_SIGNATURE_SIZE)) {
1633 /* Yikes! Still bad signature! */
1634 *error = -SCTP_IERROR_BAD_SIG;
1635 goto fail;
1636 }
1637 }
1638
1639no_hmac:
1640 /* IG Section 2.35.2:
1641 * 3) Compare the port numbers and the verification tag contained
1642 * within the COOKIE ECHO chunk to the actual port numbers and the
1643 * verification tag within the SCTP common header of the received
1644 * packet. If these values do not match the packet MUST be silently
1645 * discarded,
1646 */
1647 if (ntohl(chunk->sctp_hdr->vtag) != bear_cookie->my_vtag) {
1648 *error = -SCTP_IERROR_BAD_TAG;
1649 goto fail;
1650 }
1651
9b1dfad0 1652 if (chunk->sctp_hdr->source != bear_cookie->peer_addr.v4.sin_port ||
1da177e4
LT		 1653 ntohs(chunk->sctp_hdr->dest) != bear_cookie->my_port) {
1654 *error = -SCTP_IERROR_BAD_PORTS;
1655 goto fail;
1656 }
1657
1658 /* Check to see if the cookie is stale. If there is already
1659 * an association, there is no need to check cookie's expiration
1660 * for init collision case of lost COOKIE ACK.
f236218b
VY		 1661 * If skb has been timestamped, then use the stamp, otherwise
1662 * use current time. This introduces a small possibility that
1663 * that a cookie may be considered expired, but his would only slow
1664 * down the new association establishment instead of every packet.
1da177e4 1665 */
f236218b
VY		 1666 if (sock_flag(ep->base.sk, SOCK_TIMESTAMP))
1667 skb_get_timestamp(skb, &tv);
1668 else
1669 do_gettimeofday(&tv);
1670
a61bbcf2 1671 if (!asoc && tv_lt(bear_cookie->expiration, tv)) {
1da177e4
LT		 1672 /*
1673 * Section 3.3.10.3 Stale Cookie Error (3)
1674 *
1675 * Cause of error
1676 * ---------------
1677 * Stale Cookie Error: Indicates the receipt of a valid State
1678 * Cookie that has expired.
1679 */
1680 len = ntohs(chunk->chunk_hdr->length);
1681 *errp = sctp_make_op_error_space(asoc, chunk, len);
1682 if (*errp) {
a61bbcf2 1683 suseconds_t usecs = (tv.tv_sec -
1da177e4 1684 bear_cookie->expiration.tv_sec) * 1000000L +
a61bbcf2 1685 tv.tv_usec - bear_cookie->expiration.tv_usec;
34bcca28 1686 __be32 n = htonl(usecs);
1da177e4 1687
1da177e4 1688 sctp_init_cause(*errp, SCTP_ERROR_STALE_COOKIE,
00f1c2df
WY		 1689 sizeof(n));
1690 sctp_addto_chunk(*errp, sizeof(n), &n);
1da177e4
LT		 1691 *error = -SCTP_IERROR_STALE_COOKIE;
1692 } else
1693 *error = -SCTP_IERROR_NOMEM;
1694
1695 goto fail;
1696 }
1697
1698 /* Make a new base association. */
1699 scope = sctp_scope(sctp_source(chunk));
1700 retval = sctp_association_new(ep, ep->base.sk, scope, gfp);
1701 if (!retval) {
1702 *error = -SCTP_IERROR_NOMEM;
1703 goto fail;
1704 }
1705
1706 /* Set up our peer's port number. */
1707 retval->peer.port = ntohs(chunk->sctp_hdr->source);
1708
1709 /* Populate the association from the cookie. */
1710 memcpy(&retval->c, bear_cookie, sizeof(*bear_cookie));
1711
1712 if (sctp_assoc_set_bind_addr_from_cookie(retval, bear_cookie,
1713 GFP_ATOMIC) < 0) {
1714 *error = -SCTP_IERROR_NOMEM;
1715 goto fail;
1716 }
1717
1718 /* Also, add the destination address. */
1719 if (list_empty(&retval->base.bind_addr.address_list)) {
f57d96b2
VY		 1720 sctp_add_bind_addr(&retval->base.bind_addr, &chunk->dest,
1721 SCTP_ADDR_SRC, GFP_ATOMIC);
1da177e4
LT		 1722 }
1723
1724 retval->next_tsn = retval->c.initial_tsn;
1725 retval->ctsn_ack_point = retval->next_tsn - 1;
1726 retval->addip_serial = retval->c.initial_tsn;
1727 retval->adv_peer_ack_point = retval->ctsn_ack_point;
1728 retval->peer.prsctp_capable = retval->c.prsctp_capable;
0f3fffd8 1729 retval->peer.adaptation_ind = retval->c.adaptation_ind;
1da177e4
LT		 1730
1731 /* The INIT stuff will be done by the side effects. */
1732 return retval;
1733
1734fail:
1735 if (retval)
1736 sctp_association_free(retval);
1737
1738 return NULL;
1739
1740malformed:
1741 /* Yikes! The packet is either corrupt or deliberately
1742 * malformed.
1743 */
1744 *error = -SCTP_IERROR_MALFORMED;
1745 goto fail;
1746}
1747
1748/********************************************************************
1749 * 3rd Level Abstractions
1750 ********************************************************************/
1751
1752struct __sctp_missing {
9f81bcd9
AV		 1753 __be32 num_missing;
1754 __be16 type;
1da177e4
LT		 1755} __attribute__((packed));
1756
1757/*
1758 * Report a missing mandatory parameter.
1759 */
1760static int sctp_process_missing_param(const struct sctp_association *asoc,
1761 sctp_param_t paramtype,
1762 struct sctp_chunk *chunk,
1763 struct sctp_chunk **errp)
1764{
1765 struct __sctp_missing report;
1766 __u16 len;
1767
1768 len = WORD_ROUND(sizeof(report));
1769
1770 /* Make an ERROR chunk, preparing enough room for
1771 * returning multiple unknown parameters.
1772 */
1773 if (!*errp)
1774 *errp = sctp_make_op_error_space(asoc, chunk, len);
1775
1776 if (*errp) {
1777 report.num_missing = htonl(1);
1778 report.type = paramtype;
ebdfcad4 1779 sctp_init_cause(*errp, SCTP_ERROR_MISS_PARAM,
00f1c2df
WY		 1780 sizeof(report));
1781 sctp_addto_chunk(*errp, sizeof(report), &report);
1da177e4
LT		 1782 }
1783
1784 /* Stop processing this chunk. */
1785 return 0;
1786}
1787
1788/* Report an Invalid Mandatory Parameter. */
1789static int sctp_process_inv_mandatory(const struct sctp_association *asoc,
1790 struct sctp_chunk *chunk,
1791 struct sctp_chunk **errp)
1792{
1793 /* Invalid Mandatory Parameter Error has no payload. */
1794
1795 if (!*errp)
1796 *errp = sctp_make_op_error_space(asoc, chunk, 0);
1797
1798 if (*errp)
00f1c2df 1799 sctp_init_cause(*errp, SCTP_ERROR_INV_PARAM, 0);
1da177e4
LT		 1800
1801 /* Stop processing this chunk. */
1802 return 0;
1803}
1804
1805static int sctp_process_inv_paramlength(const struct sctp_association *asoc,
1806 struct sctp_paramhdr *param,
1807 const struct sctp_chunk *chunk,
1808 struct sctp_chunk **errp)
1809{
7ab90804
VY		 1810 /* This is a fatal error. Any accumulated non-fatal errors are
1811 * not reported.
1812 */
1813 if (*errp)
1814 sctp_chunk_free(*errp);
1815
1da177e4 1816 /* Create an error chunk and fill it in with our payload. */
ba016670 1817 *errp = sctp_make_violation_paramlen(asoc, chunk, param);
1da177e4
LT		 1818
1819 return 0;
1820}
1821
1822
1823/* Do not attempt to handle the HOST_NAME parm. However, do
1824 * send back an indicator to the peer.
1825 */
1826static int sctp_process_hn_param(const struct sctp_association *asoc,
1827 union sctp_params param,
1828 struct sctp_chunk *chunk,
1829 struct sctp_chunk **errp)
1830{
1831 __u16 len = ntohs(param.p->length);
1832
7ab90804
VY		 1833 /* Processing of the HOST_NAME parameter will generate an
1834 * ABORT. If we've accumulated any non-fatal errors, they
1835 * would be unrecognized parameters and we should not include
1836 * them in the ABORT.
1837 */
1838 if (*errp)
1839 sctp_chunk_free(*errp);
1840
1841 *errp = sctp_make_op_error_space(asoc, chunk, len);
1da177e4 1842
00f1c2df
WY		 1843 if (*errp) {
1844 sctp_init_cause(*errp, SCTP_ERROR_DNS_FAILED, len);
1845 sctp_addto_chunk(*errp, len, param.v);
1846 }
1da177e4
LT		 1847
1848 /* Stop processing this chunk. */
1849 return 0;
1850}
1851
d6701191
VY		 1852static int sctp_verify_ext_param(union sctp_params param)
1853{
1854 __u16 num_ext = ntohs(param.p->length) - sizeof(sctp_paramhdr_t);
1855 int have_auth = 0;
1856 int have_asconf = 0;
1857 int i;
1858
1859 for (i = 0; i < num_ext; i++) {
1860 switch (param.ext->chunks[i]) {
1861 case SCTP_CID_AUTH:
1862 have_auth = 1;
1863 break;
1864 case SCTP_CID_ASCONF:
1865 case SCTP_CID_ASCONF_ACK:
1866 have_asconf = 1;
1867 break;
1868 }
1869 }
1870
1871 /* ADD-IP Security: The draft requires us to ABORT or ignore the
1872 * INIT/INIT-ACK if ADD-IP is listed, but AUTH is not. Do this
1873 * only if ADD-IP is turned on and we are not backward-compatible
1874 * mode.
1875 */
1876 if (sctp_addip_noauth)
1877 return 1;
1878
1879 if (sctp_addip_enable && !have_auth && have_asconf)
1880 return 0;
1881
1882 return 1;
1883}
1884
131a47e3
VY		 1885static void sctp_process_ext_param(struct sctp_association *asoc,
1886 union sctp_params param)
1887{
1888 __u16 num_ext = ntohs(param.p->length) - sizeof(sctp_paramhdr_t);
1889 int i;
1890
1891 for (i = 0; i < num_ext; i++) {
1892 switch (param.ext->chunks[i]) {
1893 case SCTP_CID_FWD_TSN:
1894 if (sctp_prsctp_enable &&
1895 !asoc->peer.prsctp_capable)
1896 asoc->peer.prsctp_capable = 1;
1897 break;
730fc3d0
VY		 1898 case SCTP_CID_AUTH:
1899 /* if the peer reports AUTH, assume that he
1900 * supports AUTH.
1901 */
0ef46e28
VY		 1902 if (sctp_auth_enable)
1903 asoc->peer.auth_capable = 1;
730fc3d0 1904 break;
131a47e3
VY		 1905 case SCTP_CID_ASCONF:
1906 case SCTP_CID_ASCONF_ACK:
0ef46e28
VY		 1907 if (sctp_addip_enable)
1908 asoc->peer.asconf_capable = 1;
6b2f9cb6 1909 break;
131a47e3
VY		 1910 default:
1911 break;
1912 }
1913 }
1914}
1915
1da177e4
LT		 1916/* RFC 3.2.1 & the Implementers Guide 2.2.
1917 *
1918 * The Parameter Types are encoded such that the
1919 * highest-order two bits specify the action that must be
1920 * taken if the processing endpoint does not recognize the
1921 * Parameter Type.
1922 *
7ab90804
VY		 1923 * 00 - Stop processing this parameter; do not process any further
1924 * parameters within this chunk
1da177e4 1925 *
7ab90804
VY		 1926 * 01 - Stop processing this parameter, do not process any further
1927 * parameters within this chunk, and report the unrecognized
1928 * parameter in an 'Unrecognized Parameter' ERROR chunk.
1da177e4
LT		 1929 *
1930 * 10 - Skip this parameter and continue processing.
1931 *
1932 * 11 - Skip this parameter and continue processing but
1933 * report the unrecognized parameter in an
7ab90804 1934 * 'Unrecognized Parameter' ERROR chunk.
1da177e4
LT		 1935 *
1936 * Return value:
7ab90804
VY		 1937 * SCTP_IERROR_NO_ERROR - continue with the chunk
1938 * SCTP_IERROR_ERROR - stop and report an error.
1939 * SCTP_IERROR_NOMEME - out of memory.
1da177e4 1940 */
7ab90804
VY		 1941static sctp_ierror_t sctp_process_unk_param(const struct sctp_association *asoc,
1942 union sctp_params param,
1943 struct sctp_chunk *chunk,
1944 struct sctp_chunk **errp)
1da177e4 1945{
7ab90804 1946 int retval = SCTP_IERROR_NO_ERROR;
1da177e4
LT		 1947
1948 switch (param.p->type & SCTP_PARAM_ACTION_MASK) {
1949 case SCTP_PARAM_ACTION_DISCARD:
7ab90804 1950 retval = SCTP_IERROR_ERROR;
1da177e4
LT		 1951 break;
1952 case SCTP_PARAM_ACTION_SKIP:
1953 break;
7ab90804
VY		 1954 case SCTP_PARAM_ACTION_DISCARD_ERR:
1955 retval = SCTP_IERROR_ERROR;
1956 /* Fall through */
1da177e4
LT		 1957 case SCTP_PARAM_ACTION_SKIP_ERR:
1958 /* Make an ERROR chunk, preparing enough room for
1959 * returning multiple unknown parameters.
1960 */
1961 if (NULL == *errp)
1962 *errp = sctp_make_op_error_space(asoc, chunk,
1963 ntohs(chunk->chunk_hdr->length));
1964
1965 if (*errp) {
1966 sctp_init_cause(*errp, SCTP_ERROR_UNKNOWN_PARAM,
1da177e4 1967 WORD_ROUND(ntohs(param.p->length)));
00f1c2df
WY		 1968 sctp_addto_chunk(*errp,
1969 WORD_ROUND(ntohs(param.p->length)),
1970 param.v);
1da177e4
LT		 1971 } else {
1972 /* If there is no memory for generating the ERROR
1973 * report as specified, an ABORT will be triggered
1974 * to the peer and the association won't be
1975 * established.
1976 */
7ab90804 1977 retval = SCTP_IERROR_NOMEM;
1da177e4 1978 }
1da177e4
LT		 1979 break;
1980 default:
1981 break;
1982 }
1983
1984 return retval;
1985}
1986
7ab90804 1987/* Verify variable length parameters
1da177e4 1988 * Return values:
7ab90804
VY		 1989 * SCTP_IERROR_ABORT - trigger an ABORT
1990 * SCTP_IERROR_NOMEM - out of memory (abort)
1991 * SCTP_IERROR_ERROR - stop processing, trigger an ERROR
1992 * SCTP_IERROR_NO_ERROR - continue with the chunk
1da177e4 1993 */
7ab90804
VY		 1994static sctp_ierror_t sctp_verify_param(const struct sctp_association *asoc,
1995 union sctp_params param,
1996 sctp_cid_t cid,
1997 struct sctp_chunk *chunk,
1998 struct sctp_chunk **err_chunk)
1da177e4 1999{
72da7b38 2000 struct sctp_hmac_algo_param *hmacs;
7ab90804 2001 int retval = SCTP_IERROR_NO_ERROR;
72da7b38
WY		 2002 __u16 n_elt, id = 0;
2003 int i;
1da177e4
LT		 2004
2005 /* FIXME - This routine is not looking at each parameter per the
2006 * chunk type, i.e., unrecognized parameters should be further
2007 * identified based on the chunk id.
2008 */
2009
2010 switch (param.p->type) {
2011 case SCTP_PARAM_IPV4_ADDRESS:
2012 case SCTP_PARAM_IPV6_ADDRESS:
2013 case SCTP_PARAM_COOKIE_PRESERVATIVE:
2014 case SCTP_PARAM_SUPPORTED_ADDRESS_TYPES:
2015 case SCTP_PARAM_STATE_COOKIE:
2016 case SCTP_PARAM_HEARTBEAT_INFO:
2017 case SCTP_PARAM_UNRECOGNIZED_PARAMETERS:
2018 case SCTP_PARAM_ECN_CAPABLE:
0f3fffd8 2019 case SCTP_PARAM_ADAPTATION_LAYER_IND:
d6701191
VY		 2020 break;
2021
131a47e3 2022 case SCTP_PARAM_SUPPORTED_EXT:
d6701191
VY		 2023 if (!sctp_verify_ext_param(param))
2024 return SCTP_IERROR_ABORT;
1da177e4
LT		 2025 break;
2026
d6de3097
VY		 2027 case SCTP_PARAM_SET_PRIMARY:
2028 if (sctp_addip_enable)
2029 break;
2030 goto fallthrough;
2031
1da177e4
LT		 2032 case SCTP_PARAM_HOST_NAME_ADDRESS:
2033 /* Tell the peer, we won't support this param. */
7ab90804
VY		 2034 sctp_process_hn_param(asoc, param, chunk, err_chunk);
2035 retval = SCTP_IERROR_ABORT;
2036 break;
131a47e3 2037
1da177e4
LT		 2038 case SCTP_PARAM_FWD_TSN_SUPPORT:
2039 if (sctp_prsctp_enable)
2040 break;
730fc3d0
VY		 2041 goto fallthrough;
2042
2043 case SCTP_PARAM_RANDOM:
2044 if (!sctp_auth_enable)
2045 goto fallthrough;
2046
2047 /* SCTP-AUTH: Secion 6.1
2048 * If the random number is not 32 byte long the association
2049 * MUST be aborted. The ABORT chunk SHOULD contain the error
2050 * cause 'Protocol Violation'.
2051 */
2052 if (SCTP_AUTH_RANDOM_LENGTH !=
7ab90804
VY		 2053 ntohs(param.p->length) - sizeof(sctp_paramhdr_t)) {
2054 sctp_process_inv_paramlength(asoc, param.p,
730fc3d0 2055 chunk, err_chunk);
7ab90804
VY		 2056 retval = SCTP_IERROR_ABORT;
2057 }
730fc3d0
VY		 2058 break;
2059
2060 case SCTP_PARAM_CHUNKS:
2061 if (!sctp_auth_enable)
2062 goto fallthrough;
2063
2064 /* SCTP-AUTH: Section 3.2
2065 * The CHUNKS parameter MUST be included once in the INIT or
2066 * INIT-ACK chunk if the sender wants to receive authenticated
2067 * chunks. Its maximum length is 260 bytes.
2068 */
7ab90804
VY		 2069 if (260 < ntohs(param.p->length)) {
2070 sctp_process_inv_paramlength(asoc, param.p,
2071 chunk, err_chunk);
2072 retval = SCTP_IERROR_ABORT;
2073 }
730fc3d0
VY		 2074 break;
2075
2076 case SCTP_PARAM_HMAC_ALGO:
72da7b38
WY		 2077 if (!sctp_auth_enable)
2078 goto fallthrough;
2079
2080 hmacs = (struct sctp_hmac_algo_param *)param.p;
2081 n_elt = (ntohs(param.p->length) - sizeof(sctp_paramhdr_t)) >> 1;
2082
2083 /* SCTP-AUTH: Section 6.1
2084 * The HMAC algorithm based on SHA-1 MUST be supported and
2085 * included in the HMAC-ALGO parameter.
2086 */
2087 for (i = 0; i < n_elt; i++) {
2088 id = ntohs(hmacs->hmac_ids[i]);
2089
2090 if (id == SCTP_AUTH_HMAC_ID_SHA1)
2091 break;
2092 }
2093
2094 if (id != SCTP_AUTH_HMAC_ID_SHA1) {
2095 sctp_process_inv_paramlength(asoc, param.p, chunk,
2096 err_chunk);
2097 retval = SCTP_IERROR_ABORT;
2098 }
2099 break;
730fc3d0 2100fallthrough:
1da177e4
LT		 2101 default:
2102 SCTP_DEBUG_PRINTK("Unrecognized param: %d for chunk %d.\n",
2103 ntohs(param.p->type), cid);
7ab90804 2104 retval = sctp_process_unk_param(asoc, param, chunk, err_chunk);
1da177e4
LT		 2105 break;
2106 }
2107 return retval;
2108}
2109
2110/* Verify the INIT packet before we process it. */
2111int sctp_verify_init(const struct sctp_association *asoc,
2112 sctp_cid_t cid,
2113 sctp_init_chunk_t *peer_init,
2114 struct sctp_chunk *chunk,
2115 struct sctp_chunk **errp)
2116{
2117 union sctp_params param;
2118 int has_cookie = 0;
7ab90804 2119 int result;
1da177e4
LT		 2120
2121 /* Verify stream values are non-zero. */
2122 if ((0 == peer_init->init_hdr.num_outbound_streams) ||
d023f629
VY		 2123 (0 == peer_init->init_hdr.num_inbound_streams) ||
2124 (0 == peer_init->init_hdr.init_tag) ||
2125 (SCTP_DEFAULT_MINWINDOW > ntohl(peer_init->init_hdr.a_rwnd))) {
1da177e4 2126
7ab90804 2127 return sctp_process_inv_mandatory(asoc, chunk, errp);
1da177e4
LT		 2128 }
2129
2130 /* Check for missing mandatory parameters. */
2131 sctp_walk_params(param, peer_init, init_hdr.params) {
2132
2133 if (SCTP_PARAM_STATE_COOKIE == param.p->type)
2134 has_cookie = 1;
2135
2136 } /* for (loop through all parameters) */
2137
2138 /* There is a possibility that a parameter length was bad and
2139 * in that case we would have stoped walking the parameters.
2140 * The current param.p would point at the bad one.
2141 * Current consensus on the mailing list is to generate a PROTOCOL
2142 * VIOLATION error. We build the ERROR chunk here and let the normal
2143 * error handling code build and send the packet.
2144 */
7ab90804
VY		 2145 if (param.v != (void*)chunk->chunk_end)
2146 return sctp_process_inv_paramlength(asoc, param.p, chunk, errp);
1da177e4
LT		 2147
2148 /* The only missing mandatory param possible today is
2149 * the state cookie for an INIT-ACK chunk.
2150 */
7ab90804
VY		 2151 if ((SCTP_CID_INIT_ACK == cid) && !has_cookie)
2152 return sctp_process_missing_param(asoc, SCTP_PARAM_STATE_COOKIE,
2153 chunk, errp);
1da177e4 2154
7ab90804 2155 /* Verify all the variable length parameters */
1da177e4
LT		 2156 sctp_walk_params(param, peer_init, init_hdr.params) {
2157
7ab90804
VY		 2158 result = sctp_verify_param(asoc, param, cid, chunk, errp);
2159 switch (result) {
2160 case SCTP_IERROR_ABORT:
2161 case SCTP_IERROR_NOMEM:
1da177e4 2162 return 0;
7ab90804 2163 case SCTP_IERROR_ERROR:
1da177e4 2164 return 1;
7ab90804
VY		 2165 case SCTP_IERROR_NO_ERROR:
2166 default:
2167 break;
1da177e4
LT		 2168 }
2169
2170 } /* for (loop through all parameters) */
2171
2172 return 1;
2173}
2174
2175/* Unpack the parameters in an INIT packet into an association.
2176 * Returns 0 on failure, else success.
2177 * FIXME: This is an association method.
2178 */
2179int sctp_process_init(struct sctp_association *asoc, sctp_cid_t cid,
2180 const union sctp_addr *peer_addr,
dd0fc66f 2181 sctp_init_chunk_t *peer_init, gfp_t gfp)
1da177e4
LT		 2182{
2183 union sctp_params param;
2184 struct sctp_transport *transport;
2185 struct list_head *pos, *temp;
2186 char *cookie;
2187
2188 /* We must include the address that the INIT packet came from.
2189 * This is the only address that matters for an INIT packet.
2190 * When processing a COOKIE ECHO, we retrieve the from address
2191 * of the INIT from the cookie.
2192 */
2193
2194 /* This implementation defaults to making the first transport
2195 * added as the primary transport. The source address seems to
2196 * be a a better choice than any of the embedded addresses.
2197 */
4bdf4b5f 2198 if (peer_addr) {
6a1e5f33 2199 if(!sctp_assoc_add_peer(asoc, peer_addr, gfp, SCTP_ACTIVE))
1da177e4 2200 goto nomem;
4bdf4b5f 2201 }
1da177e4
LT		 2202
2203 /* Process the initialization parameters. */
1da177e4
LT		 2204 sctp_walk_params(param, peer_init, init_hdr.params) {
2205
2206 if (!sctp_process_param(asoc, param, peer_addr, gfp))
d808ad9a 2207 goto clean_up;
1da177e4
LT		 2208 }
2209
730fc3d0
VY		 2210 /* AUTH: After processing the parameters, make sure that we
2211 * have all the required info to potentially do authentications.
2212 */
2213 if (asoc->peer.auth_capable && (!asoc->peer.peer_random ||
2214 !asoc->peer.peer_hmacs))
2215 asoc->peer.auth_capable = 0;
2216
d6701191
VY		 2217 /* In a non-backward compatible mode, if the peer claims
2218 * support for ADD-IP but not AUTH, the ADD-IP spec states
2219 * that we MUST ABORT the association. Section 6. The section
2220 * also give us an option to silently ignore the packet, which
2221 * is what we'll do here.
6b2f9cb6 2222 */
73d9c4fd
VY		 2223 if (!sctp_addip_noauth &&
2224 (asoc->peer.asconf_capable && !asoc->peer.auth_capable)) {
6b2f9cb6
VY		 2225 asoc->peer.addip_disabled_mask |= (SCTP_PARAM_ADD_IP |
2226 SCTP_PARAM_DEL_IP |
2227 SCTP_PARAM_SET_PRIMARY);
88799fe5 2228 asoc->peer.asconf_capable = 0;
d6701191 2229 goto clean_up;
6b2f9cb6
VY		 2230 }
2231
3f7a87d2
FF		 2232 /* Walk list of transports, removing transports in the UNKNOWN state. */
2233 list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
2234 transport = list_entry(pos, struct sctp_transport, transports);
2235 if (transport->state == SCTP_UNKNOWN) {
2236 sctp_assoc_rm_peer(asoc, transport);
2237 }
2238 }
2239
1da177e4
LT		 2240 /* The fixed INIT headers are always in network byte
2241 * order.
2242 */
2243 asoc->peer.i.init_tag =
2244 ntohl(peer_init->init_hdr.init_tag);
2245 asoc->peer.i.a_rwnd =
2246 ntohl(peer_init->init_hdr.a_rwnd);
2247 asoc->peer.i.num_outbound_streams =
2248 ntohs(peer_init->init_hdr.num_outbound_streams);
2249 asoc->peer.i.num_inbound_streams =
2250 ntohs(peer_init->init_hdr.num_inbound_streams);
2251 asoc->peer.i.initial_tsn =
2252 ntohl(peer_init->init_hdr.initial_tsn);
2253
2254 /* Apply the upper bounds for output streams based on peer's
2255 * number of inbound streams.
2256 */
2257 if (asoc->c.sinit_num_ostreams >
2258 ntohs(peer_init->init_hdr.num_inbound_streams)) {
2259 asoc->c.sinit_num_ostreams =
2260 ntohs(peer_init->init_hdr.num_inbound_streams);
2261 }
2262
2263 if (asoc->c.sinit_max_instreams >
2264 ntohs(peer_init->init_hdr.num_outbound_streams)) {
2265 asoc->c.sinit_max_instreams =
2266 ntohs(peer_init->init_hdr.num_outbound_streams);
2267 }
2268
2269 /* Copy Initiation tag from INIT to VT_peer in cookie. */
2270 asoc->c.peer_vtag = asoc->peer.i.init_tag;
2271
2272 /* Peer Rwnd : Current calculated value of the peer's rwnd. */
2273 asoc->peer.rwnd = asoc->peer.i.a_rwnd;
2274
2275 /* Copy cookie in case we need to resend COOKIE-ECHO. */
2276 cookie = asoc->peer.cookie;
2277 if (cookie) {
af997d8c 2278 asoc->peer.cookie = kmemdup(cookie, asoc->peer.cookie_len, gfp);
1da177e4
LT		 2279 if (!asoc->peer.cookie)
2280 goto clean_up;
1da177e4
LT		 2281 }
2282
2283 /* RFC 2960 7.2.1 The initial value of ssthresh MAY be arbitrarily
2284 * high (for example, implementations MAY use the size of the receiver
2285 * advertised window).
2286 */
9dbc15f0
RD		 2287 list_for_each_entry(transport, &asoc->peer.transport_addr_list,
2288 transports) {
1da177e4
LT		 2289 transport->ssthresh = asoc->peer.i.a_rwnd;
2290 }
2291
2292 /* Set up the TSN tracking pieces. */
8e1ee18c
VY		 2293 if (!sctp_tsnmap_init(&asoc->peer.tsn_map, SCTP_TSN_MAP_INITIAL,
2294 asoc->peer.i.initial_tsn, gfp))
2295 goto clean_up;
1da177e4
LT		 2296
2297 /* RFC 2960 6.5 Stream Identifier and Stream Sequence Number
2298 *
2299 * The stream sequence number in all the streams shall start
2300 * from 0 when the association is established. Also, when the
2301 * stream sequence number reaches the value 65535 the next
2302 * stream sequence number shall be set to 0.
2303 */
2304
3f7a87d2 2305 /* Allocate storage for the negotiated streams if it is not a temporary
d808ad9a 2306 * association.
1da177e4
LT		 2307 */
2308 if (!asoc->temp) {
1da177e4
LT		 2309 int error;
2310
2311 asoc->ssnmap = sctp_ssnmap_new(asoc->c.sinit_max_instreams,
2312 asoc->c.sinit_num_ostreams, gfp);
2313 if (!asoc->ssnmap)
2314 goto clean_up;
2315
07d93967
VY		 2316 error = sctp_assoc_set_id(asoc, gfp);
2317 if (error)
1da177e4 2318 goto clean_up;
1da177e4
LT		 2319 }
2320
2321 /* ADDIP Section 4.1 ASCONF Chunk Procedures
2322 *
2323 * When an endpoint has an ASCONF signaled change to be sent to the
2324 * remote endpoint it should do the following:
2325 * ...
2326 * A2) A serial number should be assigned to the Chunk. The serial
2327 * number should be a monotonically increasing number. All serial
2328 * numbers are defined to be initialized at the start of the
2329 * association to the same value as the Initial TSN.
2330 */
2331 asoc->peer.addip_serial = asoc->peer.i.initial_tsn - 1;
2332 return 1;
2333
2334clean_up:
2335 /* Release the transport structures. */
2336 list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
2337 transport = list_entry(pos, struct sctp_transport, transports);
add52379
VY		 2338 if (transport->state != SCTP_ACTIVE)
2339 sctp_assoc_rm_peer(asoc, transport);
1da177e4 2340 }
3f7a87d2 2341
1da177e4
LT		 2342nomem:
2343 return 0;
2344}
2345
2346
2347/* Update asoc with the option described in param.
2348 *
2349 * RFC2960 3.3.2.1 Optional/Variable Length Parameters in INIT
2350 *
2351 * asoc is the association to update.
2352 * param is the variable length parameter to use for update.
2353 * cid tells us if this is an INIT, INIT ACK or COOKIE ECHO.
2354 * If the current packet is an INIT we want to minimize the amount of
2355 * work we do. In particular, we should not build transport
2356 * structures for the addresses.
2357 */
2358static int sctp_process_param(struct sctp_association *asoc,
2359 union sctp_params param,
2360 const union sctp_addr *peer_addr,
dd0fc66f 2361 gfp_t gfp)
1da177e4
LT		 2362{
2363 union sctp_addr addr;
2364 int i;
2365 __u16 sat;
2366 int retval = 1;
2367 sctp_scope_t scope;
2368 time_t stale;
2369 struct sctp_af *af;
d6de3097
VY		 2370 union sctp_addr_param *addr_param;
2371 struct sctp_transport *t;
1da177e4
LT		 2372
2373 /* We maintain all INIT parameters in network byte order all the
2374 * time. This allows us to not worry about whether the parameters
2375 * came from a fresh INIT, and INIT ACK, or were stored in a cookie.
2376 */
2377 switch (param.p->type) {
2378 case SCTP_PARAM_IPV6_ADDRESS:
2379 if (PF_INET6 != asoc->base.sk->sk_family)
2380 break;
7dab83de
VY		 2381 goto do_addr_param;
2382
1da177e4 2383 case SCTP_PARAM_IPV4_ADDRESS:
7dab83de
VY		 2384 /* v4 addresses are not allowed on v6-only socket */
2385 if (ipv6_only_sock(asoc->base.sk))
2386 break;
2387do_addr_param:
1da177e4 2388 af = sctp_get_af_specific(param_type2af(param.p->type));
dd86d136 2389 af->from_addr_param(&addr, param.addr, htons(asoc->peer.port), 0);
1da177e4 2390 scope = sctp_scope(peer_addr);
dd86d136
AV		 2391 if (sctp_in_scope(&addr, scope))
2392 if (!sctp_assoc_add_peer(asoc, &addr, gfp, SCTP_UNCONFIRMED))
1da177e4
LT		 2393 return 0;
2394 break;
2395
2396 case SCTP_PARAM_COOKIE_PRESERVATIVE:
2397 if (!sctp_cookie_preserve_enable)
2398 break;
2399
2400 stale = ntohl(param.life->lifespan_increment);
2401
2402 /* Suggested Cookie Life span increment's unit is msec,
2403 * (1/1000sec).
2404 */
2405 asoc->cookie_life.tv_sec += stale / 1000;
2406 asoc->cookie_life.tv_usec += (stale % 1000) * 1000;
2407 break;
2408
2409 case SCTP_PARAM_HOST_NAME_ADDRESS:
2410 SCTP_DEBUG_PRINTK("unimplemented SCTP_HOST_NAME_ADDRESS\n");
2411 break;
2412
2413 case SCTP_PARAM_SUPPORTED_ADDRESS_TYPES:
2414 /* Turn off the default values first so we'll know which
2415 * ones are really set by the peer.
2416 */
2417 asoc->peer.ipv4_address = 0;
2418 asoc->peer.ipv6_address = 0;
2419
140ee960
GJ		 2420 /* Assume that peer supports the address family
2421 * by which it sends a packet.
2422 */
2423 if (peer_addr->sa.sa_family == AF_INET6)
2424 asoc->peer.ipv6_address = 1;
2425 else if (peer_addr->sa.sa_family == AF_INET)
2426 asoc->peer.ipv4_address = 1;
2427
1da177e4
LT		 2428 /* Cycle through address types; avoid divide by 0. */
2429 sat = ntohs(param.p->length) - sizeof(sctp_paramhdr_t);
2430 if (sat)
2431 sat /= sizeof(__u16);
2432
2433 for (i = 0; i < sat; ++i) {
2434 switch (param.sat->types[i]) {
2435 case SCTP_PARAM_IPV4_ADDRESS:
2436 asoc->peer.ipv4_address = 1;
2437 break;
2438
2439 case SCTP_PARAM_IPV6_ADDRESS:
6e40a915
WY		 2440 if (PF_INET6 == asoc->base.sk->sk_family)
2441 asoc->peer.ipv6_address = 1;
1da177e4
LT		 2442 break;
2443
2444 case SCTP_PARAM_HOST_NAME_ADDRESS:
2445 asoc->peer.hostname_address = 1;
2446 break;
2447
2448 default: /* Just ignore anything else. */
2449 break;
3ff50b79 2450 }
1da177e4
LT		 2451 }
2452 break;
2453
2454 case SCTP_PARAM_STATE_COOKIE:
2455 asoc->peer.cookie_len =
2456 ntohs(param.p->length) - sizeof(sctp_paramhdr_t);
2457 asoc->peer.cookie = param.cookie->body;
2458 break;
2459
2460 case SCTP_PARAM_HEARTBEAT_INFO:
2461 /* Would be odd to receive, but it causes no problems. */
2462 break;
2463
2464 case SCTP_PARAM_UNRECOGNIZED_PARAMETERS:
2465 /* Rejected during verify stage. */
2466 break;
2467
2468 case SCTP_PARAM_ECN_CAPABLE:
2469 asoc->peer.ecn_capable = 1;
2470 break;
2471
0f3fffd8 2472 case SCTP_PARAM_ADAPTATION_LAYER_IND:
e69c4e0f 2473 asoc->peer.adaptation_ind = ntohl(param.aind->adaptation_ind);
1da177e4
LT		 2474 break;
2475
d6de3097 2476 case SCTP_PARAM_SET_PRIMARY:
0ef46e28
VY		 2477 if (!sctp_addip_enable)
2478 goto fall_through;
2479
d6de3097
VY		 2480 addr_param = param.v + sizeof(sctp_addip_param_t);
2481
2482 af = sctp_get_af_specific(param_type2af(param.p->type));
2483 af->from_addr_param(&addr, addr_param,
2484 htons(asoc->peer.port), 0);
2485
2486 /* if the address is invalid, we can't process it.
2487 * XXX: see spec for what to do.
2488 */
2489 if (!af->addr_valid(&addr, NULL, NULL))
2490 break;
2491
2492 t = sctp_assoc_lookup_paddr(asoc, &addr);
2493 if (!t)
2494 break;
2495
2496 sctp_assoc_set_primary(asoc, t);
2497 break;
2498
131a47e3
VY		 2499 case SCTP_PARAM_SUPPORTED_EXT:
2500 sctp_process_ext_param(asoc, param);
2501 break;
2502
1da177e4
LT		 2503 case SCTP_PARAM_FWD_TSN_SUPPORT:
2504 if (sctp_prsctp_enable) {
2505 asoc->peer.prsctp_capable = 1;
2506 break;
2507 }
d808ad9a 2508 /* Fall Through */
730fc3d0
VY		 2509 goto fall_through;
2510
2511 case SCTP_PARAM_RANDOM:
2512 if (!sctp_auth_enable)
2513 goto fall_through;
2514
2515 /* Save peer's random parameter */
2516 asoc->peer.peer_random = kmemdup(param.p,
2517 ntohs(param.p->length), gfp);
2518 if (!asoc->peer.peer_random) {
2519 retval = 0;
2520 break;
2521 }
2522 break;
2523
2524 case SCTP_PARAM_HMAC_ALGO:
2525 if (!sctp_auth_enable)
2526 goto fall_through;
2527
2528 /* Save peer's HMAC list */
2529 asoc->peer.peer_hmacs = kmemdup(param.p,
2530 ntohs(param.p->length), gfp);
2531 if (!asoc->peer.peer_hmacs) {
2532 retval = 0;
2533 break;
2534 }
2535
2536 /* Set the default HMAC the peer requested*/
2537 sctp_auth_asoc_set_default_hmac(asoc, param.hmac_algo);
2538 break;
2539
2540 case SCTP_PARAM_CHUNKS:
2541 if (!sctp_auth_enable)
2542 goto fall_through;
2543
2544 asoc->peer.peer_chunks = kmemdup(param.p,
2545 ntohs(param.p->length), gfp);
2546 if (!asoc->peer.peer_chunks)
2547 retval = 0;
2548 break;
2549fall_through:
1da177e4
LT		 2550 default:
2551 /* Any unrecognized parameters should have been caught
2552 * and handled by sctp_verify_param() which should be
2553 * called prior to this routine. Simply log the error
2554 * here.
2555 */
2556 SCTP_DEBUG_PRINTK("Ignoring param: %d for association %p.\n",
2557 ntohs(param.p->type), asoc);
2558 break;
3ff50b79 2559 }
1da177e4
LT		 2560
2561 return retval;
2562}
2563
2564/* Select a new verification tag. */
2565__u32 sctp_generate_tag(const struct sctp_endpoint *ep)
2566{
2567 /* I believe that this random number generator complies with RFC1750.
2568 * A tag of 0 is reserved for special cases (e.g. INIT).
2569 */
2570 __u32 x;
2571
2572 do {
2573 get_random_bytes(&x, sizeof(__u32));
2574 } while (x == 0);
2575
2576 return x;
2577}
2578
2579/* Select an initial TSN to send during startup. */
2580__u32 sctp_generate_tsn(const struct sctp_endpoint *ep)
2581{
2582 __u32 retval;
2583
2584 get_random_bytes(&retval, sizeof(__u32));
2585 return retval;
2586}
2587
2588/*
2589 * ADDIP 3.1.1 Address Configuration Change Chunk (ASCONF)
2590 * 0 1 2 3
2591 * 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
2592 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2593 * | Type = 0xC1 | Chunk Flags | Chunk Length |
2594 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2595 * | Serial Number |
2596 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2597 * | Address Parameter |
2598 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2599 * | ASCONF Parameter #1 |
2600 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2601 * \ \
2602 * / .... /
2603 * \ \
2604 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2605 * | ASCONF Parameter #N |
2606 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2607 *
d808ad9a 2608 * Address Parameter and other parameter will not be wrapped in this function
1da177e4
LT		 2609 */
2610static struct sctp_chunk *sctp_make_asconf(struct sctp_association *asoc,
2611 union sctp_addr *addr,
2612 int vparam_len)
2613{
2614 sctp_addiphdr_t asconf;
2615 struct sctp_chunk *retval;
2616 int length = sizeof(asconf) + vparam_len;
2617 union sctp_addr_param addrparam;
2618 int addrlen;
2619 struct sctp_af *af = sctp_get_af_specific(addr->v4.sin_family);
2620
2621 addrlen = af->to_addr_param(addr, &addrparam);
2622 if (!addrlen)
2623 return NULL;
2624 length += addrlen;
2625
2626 /* Create the chunk. */
2627 retval = sctp_make_chunk(asoc, SCTP_CID_ASCONF, 0, length);
2628 if (!retval)
2629 return NULL;
2630
2631 asconf.serial = htonl(asoc->addip_serial++);
2632
2633 retval->subh.addip_hdr =
2634 sctp_addto_chunk(retval, sizeof(asconf), &asconf);
2635 retval->param_hdr.v =
2636 sctp_addto_chunk(retval, addrlen, &addrparam);
2637
2638 return retval;
2639}
2640
2641/* ADDIP
2642 * 3.2.1 Add IP Address
2643 * 0 1 2 3
2644 * 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
2645 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2646 * | Type = 0xC001 | Length = Variable |
2647 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2648 * | ASCONF-Request Correlation ID |
2649 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2650 * | Address Parameter |
2651 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2652 *
2653 * 3.2.2 Delete IP Address
2654 * 0 1 2 3
2655 * 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
2656 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2657 * | Type = 0xC002 | Length = Variable |
2658 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2659 * | ASCONF-Request Correlation ID |
2660 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2661 * | Address Parameter |
2662 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2663 *
2664 */
2665struct sctp_chunk *sctp_make_asconf_update_ip(struct sctp_association *asoc,
2666 union sctp_addr *laddr,
2667 struct sockaddr *addrs,
2668 int addrcnt,
dbc16db1 2669 __be16 flags)
1da177e4
LT		 2670{
2671 sctp_addip_param_t param;
2672 struct sctp_chunk *retval;
2673 union sctp_addr_param addr_param;
2674 union sctp_addr *addr;
2675 void *addr_buf;
2676 struct sctp_af *af;
2677 int paramlen = sizeof(param);
2678 int addr_param_len = 0;
2679 int totallen = 0;
2680 int i;
2681
2682 /* Get total length of all the address parameters. */
2683 addr_buf = addrs;
2684 for (i = 0; i < addrcnt; i++) {
2685 addr = (union sctp_addr *)addr_buf;
2686 af = sctp_get_af_specific(addr->v4.sin_family);
2687 addr_param_len = af->to_addr_param(addr, &addr_param);
2688
2689 totallen += paramlen;
2690 totallen += addr_param_len;
2691
2692 addr_buf += af->sockaddr_len;
2693 }
2694
2695 /* Create an asconf chunk with the required length. */
2696 retval = sctp_make_asconf(asoc, laddr, totallen);
2697 if (!retval)
2698 return NULL;
2699
2700 /* Add the address parameters to the asconf chunk. */
2701 addr_buf = addrs;
2702 for (i = 0; i < addrcnt; i++) {
2703 addr = (union sctp_addr *)addr_buf;
2704 af = sctp_get_af_specific(addr->v4.sin_family);
2705 addr_param_len = af->to_addr_param(addr, &addr_param);
2706 param.param_hdr.type = flags;
2707 param.param_hdr.length = htons(paramlen + addr_param_len);
2708 param.crr_id = i;
2709
2710 sctp_addto_chunk(retval, paramlen, &param);
2711 sctp_addto_chunk(retval, addr_param_len, &addr_param);
2712
2713 addr_buf += af->sockaddr_len;
2714 }
2715 return retval;
2716}
2717
2718/* ADDIP
2719 * 3.2.4 Set Primary IP Address
2720 * 0 1 2 3
2721 * 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
2722 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2723 * | Type =0xC004 | Length = Variable |
2724 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2725 * | ASCONF-Request Correlation ID |
2726 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2727 * | Address Parameter |
2728 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2729 *
d808ad9a 2730 * Create an ASCONF chunk with Set Primary IP address parameter.
1da177e4
LT		 2731 */
2732struct sctp_chunk *sctp_make_asconf_set_prim(struct sctp_association *asoc,
2733 union sctp_addr *addr)
2734{
2735 sctp_addip_param_t param;
2736 struct sctp_chunk *retval;
2737 int len = sizeof(param);
2738 union sctp_addr_param addrparam;
2739 int addrlen;
2740 struct sctp_af *af = sctp_get_af_specific(addr->v4.sin_family);
2741
2742 addrlen = af->to_addr_param(addr, &addrparam);
2743 if (!addrlen)
2744 return NULL;
2745 len += addrlen;
2746
2747 /* Create the chunk and make asconf header. */
2748 retval = sctp_make_asconf(asoc, addr, len);
2749 if (!retval)
2750 return NULL;
2751
2752 param.param_hdr.type = SCTP_PARAM_SET_PRIMARY;
2753 param.param_hdr.length = htons(len);
2754 param.crr_id = 0;
2755
2756 sctp_addto_chunk(retval, sizeof(param), &param);
2757 sctp_addto_chunk(retval, addrlen, &addrparam);
2758
2759 return retval;
2760}
2761
2762/* ADDIP 3.1.2 Address Configuration Acknowledgement Chunk (ASCONF-ACK)
2763 * 0 1 2 3
2764 * 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
2765 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2766 * | Type = 0x80 | Chunk Flags | Chunk Length |
2767 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2768 * | Serial Number |
2769 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2770 * | ASCONF Parameter Response#1 |
2771 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2772 * \ \
2773 * / .... /
2774 * \ \
2775 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2776 * | ASCONF Parameter Response#N |
2777 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2778 *
d808ad9a 2779 * Create an ASCONF_ACK chunk with enough space for the parameter responses.
1da177e4
LT		 2780 */
2781static struct sctp_chunk *sctp_make_asconf_ack(const struct sctp_association *asoc,
2782 __u32 serial, int vparam_len)
2783{
2784 sctp_addiphdr_t asconf;
2785 struct sctp_chunk *retval;
2786 int length = sizeof(asconf) + vparam_len;
2787
2788 /* Create the chunk. */
2789 retval = sctp_make_chunk(asoc, SCTP_CID_ASCONF_ACK, 0, length);
2790 if (!retval)
2791 return NULL;
2792
2793 asconf.serial = htonl(serial);
2794
2795 retval->subh.addip_hdr =
2796 sctp_addto_chunk(retval, sizeof(asconf), &asconf);
2797
2798 return retval;
2799}
2800
2801/* Add response parameters to an ASCONF_ACK chunk. */
9f81bcd9 2802static void sctp_add_asconf_response(struct sctp_chunk *chunk, __be32 crr_id,
dbc16db1 2803 __be16 err_code, sctp_addip_param_t *asconf_param)
1da177e4
LT		 2804{
2805 sctp_addip_param_t ack_param;
2806 sctp_errhdr_t err_param;
2807 int asconf_param_len = 0;
2808 int err_param_len = 0;
dbc16db1 2809 __be16 response_type;
1da177e4
LT		 2810
2811 if (SCTP_ERROR_NO_ERROR == err_code) {
2812 response_type = SCTP_PARAM_SUCCESS_REPORT;
2813 } else {
2814 response_type = SCTP_PARAM_ERR_CAUSE;
2815 err_param_len = sizeof(err_param);
2816 if (asconf_param)
2817 asconf_param_len =
2818 ntohs(asconf_param->param_hdr.length);
2819 }
2820
d808ad9a 2821 /* Add Success Indication or Error Cause Indication parameter. */
1da177e4
LT		 2822 ack_param.param_hdr.type = response_type;
2823 ack_param.param_hdr.length = htons(sizeof(ack_param) +
2824 err_param_len +
2825 asconf_param_len);
2826 ack_param.crr_id = crr_id;
2827 sctp_addto_chunk(chunk, sizeof(ack_param), &ack_param);
2828
2829 if (SCTP_ERROR_NO_ERROR == err_code)
2830 return;
2831
2832 /* Add Error Cause parameter. */
2833 err_param.cause = err_code;
2834 err_param.length = htons(err_param_len + asconf_param_len);
2835 sctp_addto_chunk(chunk, err_param_len, &err_param);
2836
2837 /* Add the failed TLV copied from ASCONF chunk. */
2838 if (asconf_param)
2839 sctp_addto_chunk(chunk, asconf_param_len, asconf_param);
2840}
2841
2842/* Process a asconf parameter. */
dbc16db1 2843static __be16 sctp_process_asconf_param(struct sctp_association *asoc,
1da177e4
LT		 2844 struct sctp_chunk *asconf,
2845 sctp_addip_param_t *asconf_param)
2846{
2847 struct sctp_transport *peer;
2848 struct sctp_af *af;
2849 union sctp_addr addr;
1da177e4 2850 union sctp_addr_param *addr_param;
5f242a13 2851
c1cc678a
PM		 2852 addr_param = (union sctp_addr_param *)
2853 ((void *)asconf_param + sizeof(sctp_addip_param_t));
2854
c4492586
WY		 2855 switch (addr_param->v4.param_hdr.type) {
2856 case SCTP_PARAM_IPV6_ADDRESS:
2857 if (!asoc->peer.ipv6_address)
2858 return SCTP_ERROR_INV_PARAM;
2859 break;
2860 case SCTP_PARAM_IPV4_ADDRESS:
2861 if (!asoc->peer.ipv4_address)
2862 return SCTP_ERROR_INV_PARAM;
2863 break;
2864 default:
2865 return SCTP_ERROR_INV_PARAM;
2866 }
2867
1da177e4
LT		 2868 af = sctp_get_af_specific(param_type2af(addr_param->v4.param_hdr.type));
2869 if (unlikely(!af))
2870 return SCTP_ERROR_INV_PARAM;
2871
dd86d136 2872 af->from_addr_param(&addr, addr_param, htons(asoc->peer.port), 0);
42e30bf3
VY		 2873
2874 /* ADDIP 4.2.1 This parameter MUST NOT contain a broadcast
2875 * or multicast address.
2876 * (note: wildcard is permitted and requires special handling so
2877 * make sure we check for that)
2878 */
2879 if (!af->is_any(&addr) && !af->addr_valid(&addr, NULL, asconf->skb))
2880 return SCTP_ERROR_INV_PARAM;
2881
1da177e4
LT		 2882 switch (asconf_param->param_hdr.type) {
2883 case SCTP_PARAM_ADD_IP:
42e30bf3
VY		 2884 /* Section 4.2.1:
2885 * If the address 0.0.0.0 or ::0 is provided, the source
2886 * address of the packet MUST be added.
2887 */
2888 if (af->is_any(&addr))
2889 memcpy(&addr, &asconf->source, sizeof(addr));
2890
1da177e4 2891 /* ADDIP 4.3 D9) If an endpoint receives an ADD IP address
d808ad9a
YH		 2892 * request and does not have the local resources to add this
2893 * new address to the association, it MUST return an Error
2894 * Cause TLV set to the new error code 'Operation Refused
2895 * Due to Resource Shortage'.
2896 */
1da177e4 2897
dd86d136 2898 peer = sctp_assoc_add_peer(asoc, &addr, GFP_ATOMIC, SCTP_UNCONFIRMED);
1da177e4
LT		 2899 if (!peer)
2900 return SCTP_ERROR_RSRC_LOW;
2901
2902 /* Start the heartbeat timer. */
2903 if (!mod_timer(&peer->hb_timer, sctp_transport_timeout(peer)))
2904 sctp_transport_hold(peer);
2905 break;
2906 case SCTP_PARAM_DEL_IP:
2907 /* ADDIP 4.3 D7) If a request is received to delete the
d808ad9a
YH		 2908 * last remaining IP address of a peer endpoint, the receiver
2909 * MUST send an Error Cause TLV with the error cause set to the
2910 * new error code 'Request to Delete Last Remaining IP Address'.
2911 */
42e30bf3 2912 if (asoc->peer.transport_count == 1)
1da177e4
LT		 2913 return SCTP_ERROR_DEL_LAST_IP;
2914
2915 /* ADDIP 4.3 D8) If a request is received to delete an IP
2916 * address which is also the source address of the IP packet
2917 * which contained the ASCONF chunk, the receiver MUST reject
2918 * this request. To reject the request the receiver MUST send
2919 * an Error Cause TLV set to the new error code 'Request to
2920 * Delete Source IP Address'
2921 */
6a1e5f33 2922 if (sctp_cmp_addr_exact(sctp_source(asconf), &addr))
1da177e4
LT		 2923 return SCTP_ERROR_DEL_SRC_IP;
2924
42e30bf3
VY		 2925 /* Section 4.2.2
2926 * If the address 0.0.0.0 or ::0 is provided, all
2927 * addresses of the peer except the source address of the
2928 * packet MUST be deleted.
2929 */
2930 if (af->is_any(&addr)) {
2931 sctp_assoc_set_primary(asoc, asconf->transport);
2932 sctp_assoc_del_nonprimary_peers(asoc,
2933 asconf->transport);
2934 } else
2935 sctp_assoc_del_peer(asoc, &addr);
1da177e4
LT		 2936 break;
2937 case SCTP_PARAM_SET_PRIMARY:
42e30bf3
VY		 2938 /* ADDIP Section 4.2.4
2939 * If the address 0.0.0.0 or ::0 is provided, the receiver
2940 * MAY mark the source address of the packet as its
2941 * primary.
2942 */
2943 if (af->is_any(&addr))
2944 memcpy(&addr.v4, sctp_source(asconf), sizeof(addr));
2945
dd86d136 2946 peer = sctp_assoc_lookup_paddr(asoc, &addr);
1da177e4
LT		 2947 if (!peer)
2948 return SCTP_ERROR_INV_PARAM;
2949
2950 sctp_assoc_set_primary(asoc, peer);
2951 break;
2952 default:
2953 return SCTP_ERROR_INV_PARAM;
2954 break;
2955 }
2956
2957 return SCTP_ERROR_NO_ERROR;
2958}
2959
6f4c618d
WY		 2960/* Verify the ASCONF packet before we process it. */
2961int sctp_verify_asconf(const struct sctp_association *asoc,
2962 struct sctp_paramhdr *param_hdr, void *chunk_end,
2963 struct sctp_paramhdr **errp) {
2964 sctp_addip_param_t *asconf_param;
2965 union sctp_params param;
2966 int length, plen;
2967
2968 param.v = (sctp_paramhdr_t *) param_hdr;
2969 while (param.v <= chunk_end - sizeof(sctp_paramhdr_t)) {
2970 length = ntohs(param.p->length);
2971 *errp = param.p;
2972
2973 if (param.v > chunk_end - length ||
2974 length < sizeof(sctp_paramhdr_t))
2975 return 0;
2976
2977 switch (param.p->type) {
2978 case SCTP_PARAM_ADD_IP:
2979 case SCTP_PARAM_DEL_IP:
2980 case SCTP_PARAM_SET_PRIMARY:
2981 asconf_param = (sctp_addip_param_t *)param.v;
2982 plen = ntohs(asconf_param->param_hdr.length);
2983 if (plen < sizeof(sctp_addip_param_t) +
2984 sizeof(sctp_paramhdr_t))
2985 return 0;
2986 break;
2987 case SCTP_PARAM_SUCCESS_REPORT:
2988 case SCTP_PARAM_ADAPTATION_LAYER_IND:
2989 if (length != sizeof(sctp_addip_param_t))
2990 return 0;
2991
2992 break;
2993 default:
2994 break;
2995 }
2996
2997 param.v += WORD_ROUND(length);
2998 }
2999
3000 if (param.v != chunk_end)
3001 return 0;
3002
3003 return 1;
3004}
3005
d808ad9a 3006/* Process an incoming ASCONF chunk with the next expected serial no. and
1da177e4
LT		 3007 * return an ASCONF_ACK chunk to be sent in response.
3008 */
3009struct sctp_chunk *sctp_process_asconf(struct sctp_association *asoc,
3010 struct sctp_chunk *asconf)
3011{
3012 sctp_addiphdr_t *hdr;
3013 union sctp_addr_param *addr_param;
3014 sctp_addip_param_t *asconf_param;
3015 struct sctp_chunk *asconf_ack;
3016
dbc16db1 3017 __be16 err_code;
1da177e4 3018 int length = 0;
f3830ccc 3019 int chunk_len;
1da177e4
LT		 3020 __u32 serial;
3021 int all_param_pass = 1;
3022
f3830ccc 3023 chunk_len = ntohs(asconf->chunk_hdr->length) - sizeof(sctp_chunkhdr_t);
1da177e4
LT		 3024 hdr = (sctp_addiphdr_t *)asconf->skb->data;
3025 serial = ntohl(hdr->serial);
3026
d808ad9a 3027 /* Skip the addiphdr and store a pointer to address parameter. */
1da177e4
LT		 3028 length = sizeof(sctp_addiphdr_t);
3029 addr_param = (union sctp_addr_param *)(asconf->skb->data + length);
3030 chunk_len -= length;
3031
3032 /* Skip the address parameter and store a pointer to the first
7aa1b54b 3033 * asconf parameter.
d808ad9a 3034 */
1da177e4
LT		 3035 length = ntohs(addr_param->v4.param_hdr.length);
3036 asconf_param = (sctp_addip_param_t *)((void *)addr_param + length);
3037 chunk_len -= length;
3038
d808ad9a 3039 /* create an ASCONF_ACK chunk.
1da177e4
LT		 3040 * Based on the definitions of parameters, we know that the size of
3041 * ASCONF_ACK parameters are less than or equal to the twice of ASCONF
7aa1b54b 3042 * parameters.
1da177e4
LT		 3043 */
3044 asconf_ack = sctp_make_asconf_ack(asoc, serial, chunk_len * 2);
3045 if (!asconf_ack)
3046 goto done;
3047
3048 /* Process the TLVs contained within the ASCONF chunk. */
3049 while (chunk_len > 0) {
3050 err_code = sctp_process_asconf_param(asoc, asconf,
3051 asconf_param);
3052 /* ADDIP 4.1 A7)
3053 * If an error response is received for a TLV parameter,
3054 * all TLVs with no response before the failed TLV are
3055 * considered successful if not reported. All TLVs after
3056 * the failed response are considered unsuccessful unless
3057 * a specific success indication is present for the parameter.
3058 */
3059 if (SCTP_ERROR_NO_ERROR != err_code)
3060 all_param_pass = 0;
3061
3062 if (!all_param_pass)
3063 sctp_add_asconf_response(asconf_ack,
3064 asconf_param->crr_id, err_code,
3065 asconf_param);
3066
3067 /* ADDIP 4.3 D11) When an endpoint receiving an ASCONF to add
3068 * an IP address sends an 'Out of Resource' in its response, it
3069 * MUST also fail any subsequent add or delete requests bundled
d808ad9a 3070 * in the ASCONF.
1da177e4
LT		 3071 */
3072 if (SCTP_ERROR_RSRC_LOW == err_code)
3073 goto done;
3074
3075 /* Move to the next ASCONF param. */
3076 length = ntohs(asconf_param->param_hdr.length);
3077 asconf_param = (sctp_addip_param_t *)((void *)asconf_param +
3078 length);
3079 chunk_len -= length;
3080 }
d808ad9a 3081
1da177e4
LT		 3082done:
3083 asoc->peer.addip_serial++;
3084
3085 /* If we are sending a new ASCONF_ACK hold a reference to it in assoc
d808ad9a 3086 * after freeing the reference to old asconf ack if any.
1da177e4
LT		 3087 */
3088 if (asconf_ack) {
1da177e4 3089 sctp_chunk_hold(asconf_ack);
a08de64d
VY		 3090 list_add_tail(&asconf_ack->transmitted_list,
3091 &asoc->asconf_ack_list);
1da177e4
LT		 3092 }
3093
3094 return asconf_ack;
3095}
3096
3097/* Process a asconf parameter that is successfully acked. */
3098static int sctp_asconf_param_success(struct sctp_association *asoc,
3099 sctp_addip_param_t *asconf_param)
3100{
3101 struct sctp_af *af;
3102 union sctp_addr addr;
3103 struct sctp_bind_addr *bp = &asoc->base.bind_addr;
3104 union sctp_addr_param *addr_param;
1da177e4 3105 struct sctp_transport *transport;
dc022a98 3106 struct sctp_sockaddr_entry *saddr;
1da177e4
LT		 3107 int retval = 0;
3108
3109 addr_param = (union sctp_addr_param *)
3110 ((void *)asconf_param + sizeof(sctp_addip_param_t));
3111
3112 /* We have checked the packet before, so we do not check again. */
3113 af = sctp_get_af_specific(param_type2af(addr_param->v4.param_hdr.type));
dd86d136 3114 af->from_addr_param(&addr, addr_param, htons(bp->port), 0);
1da177e4
LT		 3115
3116 switch (asconf_param->param_hdr.type) {
3117 case SCTP_PARAM_ADD_IP:
559cf710
VY		 3118 /* This is always done in BH context with a socket lock
3119 * held, so the list can not change.
3120 */
0ed90fb0 3121 local_bh_disable();
559cf710 3122 list_for_each_entry(saddr, &bp->address_list, list) {
dd86d136 3123 if (sctp_cmp_addr_exact(&saddr->a, &addr))
f57d96b2 3124 saddr->state = SCTP_ADDR_SRC;
dc022a98 3125 }
0ed90fb0 3126 local_bh_enable();
1da177e4
LT		 3127 break;
3128 case SCTP_PARAM_DEL_IP:
0ed90fb0
VY		 3129 local_bh_disable();
3130 retval = sctp_del_bind_addr(bp, &addr);
3131 local_bh_enable();
9dbc15f0
RD		 3132 list_for_each_entry(transport, &asoc->peer.transport_addr_list,
3133 transports) {
dc022a98 3134 dst_release(transport->dst);
1da177e4
LT		 3135 sctp_transport_route(transport, NULL,
3136 sctp_sk(asoc->base.sk));
3137 }
3138 break;
3139 default:
3140 break;
3141 }
3142
3143 return retval;
3144}
3145
3146/* Get the corresponding ASCONF response error code from the ASCONF_ACK chunk
3147 * for the given asconf parameter. If there is no response for this parameter,
d808ad9a 3148 * return the error code based on the third argument 'no_err'.
1da177e4
LT		 3149 * ADDIP 4.1
3150 * A7) If an error response is received for a TLV parameter, all TLVs with no
3151 * response before the failed TLV are considered successful if not reported.
3152 * All TLVs after the failed response are considered unsuccessful unless a
3153 * specific success indication is present for the parameter.
3154 */
dbc16db1 3155static __be16 sctp_get_asconf_response(struct sctp_chunk *asconf_ack,
1da177e4
LT		 3156 sctp_addip_param_t *asconf_param,
3157 int no_err)
3158{
3159 sctp_addip_param_t *asconf_ack_param;
3160 sctp_errhdr_t *err_param;
3161 int length;
f3830ccc 3162 int asconf_ack_len;
dbc16db1 3163 __be16 err_code;
1da177e4
LT		 3164
3165 if (no_err)
3166 err_code = SCTP_ERROR_NO_ERROR;
3167 else
3168 err_code = SCTP_ERROR_REQ_REFUSED;
3169
f3830ccc
WY		 3170 asconf_ack_len = ntohs(asconf_ack->chunk_hdr->length) -
3171 sizeof(sctp_chunkhdr_t);
3172
1da177e4
LT		 3173 /* Skip the addiphdr from the asconf_ack chunk and store a pointer to
3174 * the first asconf_ack parameter.
d808ad9a 3175 */
1da177e4
LT		 3176 length = sizeof(sctp_addiphdr_t);
3177 asconf_ack_param = (sctp_addip_param_t *)(asconf_ack->skb->data +
3178 length);
3179 asconf_ack_len -= length;
3180
3181 while (asconf_ack_len > 0) {
3182 if (asconf_ack_param->crr_id == asconf_param->crr_id) {
3183 switch(asconf_ack_param->param_hdr.type) {
3184 case SCTP_PARAM_SUCCESS_REPORT:
3185 return SCTP_ERROR_NO_ERROR;
3186 case SCTP_PARAM_ERR_CAUSE:
3187 length = sizeof(sctp_addip_param_t);
3188 err_param = (sctp_errhdr_t *)
3189 ((void *)asconf_ack_param + length);
3190 asconf_ack_len -= length;
3191 if (asconf_ack_len > 0)
3192 return err_param->cause;
3193 else
3194 return SCTP_ERROR_INV_PARAM;
3195 break;
3196 default:
3197 return SCTP_ERROR_INV_PARAM;
3198 }
3199 }
3200
3201 length = ntohs(asconf_ack_param->param_hdr.length);
3202 asconf_ack_param = (sctp_addip_param_t *)
3203 ((void *)asconf_ack_param + length);
3204 asconf_ack_len -= length;
3205 }
3206
3207 return err_code;
3208}
3209
3210/* Process an incoming ASCONF_ACK chunk against the cached last ASCONF chunk. */
3211int sctp_process_asconf_ack(struct sctp_association *asoc,
3212 struct sctp_chunk *asconf_ack)
3213{
3214 struct sctp_chunk *asconf = asoc->addip_last_asconf;
3215 union sctp_addr_param *addr_param;
3216 sctp_addip_param_t *asconf_param;
3217 int length = 0;
3218 int asconf_len = asconf->skb->len;
3219 int all_param_pass = 0;
3220 int no_err = 1;
3221 int retval = 0;
dbc16db1 3222 __be16 err_code = SCTP_ERROR_NO_ERROR;
1da177e4
LT		 3223
3224 /* Skip the chunkhdr and addiphdr from the last asconf sent and store
3225 * a pointer to address parameter.
d808ad9a 3226 */
1da177e4
LT		 3227 length = sizeof(sctp_addip_chunk_t);
3228 addr_param = (union sctp_addr_param *)(asconf->skb->data + length);
3229 asconf_len -= length;
3230
3231 /* Skip the address parameter in the last asconf sent and store a
7aa1b54b 3232 * pointer to the first asconf parameter.
d808ad9a 3233 */
1da177e4
LT		 3234 length = ntohs(addr_param->v4.param_hdr.length);
3235 asconf_param = (sctp_addip_param_t *)((void *)addr_param + length);
3236 asconf_len -= length;
3237
3238 /* ADDIP 4.1
3239 * A8) If there is no response(s) to specific TLV parameter(s), and no
3240 * failures are indicated, then all request(s) are considered
3241 * successful.
3242 */
3243 if (asconf_ack->skb->len == sizeof(sctp_addiphdr_t))
3244 all_param_pass = 1;
3245
3246 /* Process the TLVs contained in the last sent ASCONF chunk. */
3247 while (asconf_len > 0) {
3248 if (all_param_pass)
3249 err_code = SCTP_ERROR_NO_ERROR;
3250 else {
3251 err_code = sctp_get_asconf_response(asconf_ack,
3252 asconf_param,
3253 no_err);
3254 if (no_err && (SCTP_ERROR_NO_ERROR != err_code))
3255 no_err = 0;
3256 }
3257
3258 switch (err_code) {
3259 case SCTP_ERROR_NO_ERROR:
3260 retval = sctp_asconf_param_success(asoc, asconf_param);
3261 break;
3262
3263 case SCTP_ERROR_RSRC_LOW:
3264 retval = 1;
3265 break;
3266
3267 case SCTP_ERROR_INV_PARAM:
3268 /* Disable sending this type of asconf parameter in
3269 * future.
d808ad9a 3270 */
1da177e4
LT		 3271 asoc->peer.addip_disabled_mask |=
3272 asconf_param->param_hdr.type;
3273 break;
3274
3275 case SCTP_ERROR_REQ_REFUSED:
3276 case SCTP_ERROR_DEL_LAST_IP:
3277 case SCTP_ERROR_DEL_SRC_IP:
3278 default:
3279 break;
3280 }
3281
3282 /* Skip the processed asconf parameter and move to the next
3283 * one.
d808ad9a 3284 */
1da177e4
LT		 3285 length = ntohs(asconf_param->param_hdr.length);
3286 asconf_param = (sctp_addip_param_t *)((void *)asconf_param +
3287 length);
3288 asconf_len -= length;
3289 }
3290
3291 /* Free the cached last sent asconf chunk. */
5f9646c3 3292 list_del_init(&asconf->transmitted_list);
1da177e4
LT		 3293 sctp_chunk_free(asconf);
3294 asoc->addip_last_asconf = NULL;
3295
3296 /* Send the next asconf chunk from the addip chunk queue. */
79af02c2
DM		 3297 if (!list_empty(&asoc->addip_chunk_list)) {
3298 struct list_head *entry = asoc->addip_chunk_list.next;
3299 asconf = list_entry(entry, struct sctp_chunk, list);
3300
3301 list_del_init(entry);
3302
1da177e4
LT		 3303 /* Hold the chunk until an ASCONF_ACK is received. */
3304 sctp_chunk_hold(asconf);
3305 if (sctp_primitive_ASCONF(asoc, asconf))
3306 sctp_chunk_free(asconf);
3307 else
3308 asoc->addip_last_asconf = asconf;
3309 }
3310
3311 return retval;
3312}
3313
d808ad9a 3314/* Make a FWD TSN chunk. */
1da177e4
LT		 3315struct sctp_chunk *sctp_make_fwdtsn(const struct sctp_association *asoc,
3316 __u32 new_cum_tsn, size_t nstreams,
3317 struct sctp_fwdtsn_skip *skiplist)
3318{
3319 struct sctp_chunk *retval = NULL;
3320 struct sctp_fwdtsn_chunk *ftsn_chunk;
d808ad9a 3321 struct sctp_fwdtsn_hdr ftsn_hdr;
1da177e4
LT		 3322 struct sctp_fwdtsn_skip skip;
3323 size_t hint;
3324 int i;
3325
3326 hint = (nstreams + 1) * sizeof(__u32);
3327
1da177e4
LT		 3328 retval = sctp_make_chunk(asoc, SCTP_CID_FWD_TSN, 0, hint);
3329
3330 if (!retval)
3331 return NULL;
3332
3333 ftsn_chunk = (struct sctp_fwdtsn_chunk *)retval->subh.fwdtsn_hdr;
3334
3335 ftsn_hdr.new_cum_tsn = htonl(new_cum_tsn);
3336 retval->subh.fwdtsn_hdr =
3337 sctp_addto_chunk(retval, sizeof(ftsn_hdr), &ftsn_hdr);
3338
3339 for (i = 0; i < nstreams; i++) {
3340 skip.stream = skiplist[i].stream;
3341 skip.ssn = skiplist[i].ssn;
3342 sctp_addto_chunk(retval, sizeof(skip), &skip);
3343 }
3344
3345 return retval;
3346}
Linux 6.x block layer and io_uring tree(s)