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1da177e4
LT		 1/* SCTP kernel reference Implementation
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 *
7 * This file is part of the SCTP kernel reference Implementation
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 *
13 * The SCTP reference implementation is free software;
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 *
19 * The SCTP reference implementation is distributed in the hope that it
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>
59#include <asm/scatterlist.h>
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);
1da177e4
LT		 80
81/* What was the inbound interface for this chunk? */
82int sctp_chunk_iif(const struct sctp_chunk *chunk)
83{
84 struct sctp_af *af;
85 int iif = 0;
86
eddc9ec5 87 af = sctp_get_af_specific(ipver2af(ip_hdr(chunk->skb)->version));
1da177e4
LT		 88 if (af)
89 iif = af->skb_iif(chunk->skb);
90
91 return iif;
92}
93
94/* RFC 2960 3.3.2 Initiation (INIT) (1)
95 *
96 * Note 2: The ECN capable field is reserved for future use of
97 * Explicit Congestion Notification.
98 */
99static const struct sctp_paramhdr ecap_param = {
100 SCTP_PARAM_ECN_CAPABLE,
101 __constant_htons(sizeof(struct sctp_paramhdr)),
102};
103static const struct sctp_paramhdr prsctp_param = {
104 SCTP_PARAM_FWD_TSN_SUPPORT,
105 __constant_htons(sizeof(struct sctp_paramhdr)),
106};
107
108/* A helper to initialize to initialize an op error inside a
109 * provided chunk, as most cause codes will be embedded inside an
110 * abort chunk.
111 */
5bf2db03 112void sctp_init_cause(struct sctp_chunk *chunk, __be16 cause_code,
00f1c2df 113 size_t paylen)
1da177e4
LT		 114{
115 sctp_errhdr_t err;
1da177e4
LT		 116 __u16 len;
117
d808ad9a 118 /* Cause code constants are now defined in network order. */
1da177e4
LT		 119 err.cause = cause_code;
120 len = sizeof(sctp_errhdr_t) + paylen;
1da177e4 121 err.length = htons(len);
4a1c0107 122 chunk->subh.err_hdr = sctp_addto_chunk(chunk, sizeof(sctp_errhdr_t), &err);
1da177e4
LT		 123}
124
125/* 3.3.2 Initiation (INIT) (1)
126 *
127 * This chunk is used to initiate a SCTP association between two
128 * endpoints. The format of the INIT chunk is shown below:
129 *
130 * 0 1 2 3
131 * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
132 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
133 * | Type = 1 | Chunk Flags | Chunk Length |
134 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
135 * | Initiate Tag |
136 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
137 * | Advertised Receiver Window Credit (a_rwnd) |
138 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
139 * | Number of Outbound Streams | Number of Inbound Streams |
140 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
141 * | Initial TSN |
142 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
143 * \ \
144 * / Optional/Variable-Length Parameters /
145 * \ \
146 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
147 *
148 *
149 * The INIT chunk contains the following parameters. Unless otherwise
150 * noted, each parameter MUST only be included once in the INIT chunk.
151 *
152 * Fixed Parameters Status
153 * ----------------------------------------------
154 * Initiate Tag Mandatory
155 * Advertised Receiver Window Credit Mandatory
156 * Number of Outbound Streams Mandatory
157 * Number of Inbound Streams Mandatory
158 * Initial TSN Mandatory
159 *
160 * Variable Parameters Status Type Value
161 * -------------------------------------------------------------
162 * IPv4 Address (Note 1) Optional 5
163 * IPv6 Address (Note 1) Optional 6
164 * Cookie Preservative Optional 9
165 * Reserved for ECN Capable (Note 2) Optional 32768 (0x8000)
166 * Host Name Address (Note 3) Optional 11
167 * Supported Address Types (Note 4) Optional 12
168 */
169struct sctp_chunk *sctp_make_init(const struct sctp_association *asoc,
170 const struct sctp_bind_addr *bp,
dd0fc66f 171 gfp_t gfp, int vparam_len)
1da177e4
LT		 172{
173 sctp_inithdr_t init;
174 union sctp_params addrs;
175 size_t chunksize;
176 struct sctp_chunk *retval = NULL;
177 int num_types, addrs_len = 0;
178 struct sctp_sock *sp;
179 sctp_supported_addrs_param_t sat;
3dbe8656 180 __be16 types[2];
0f3fffd8 181 sctp_adaptation_ind_param_t aiparam;
131a47e3
VY		 182 sctp_supported_ext_param_t ext_param;
183 int num_ext = 0;
184 __u8 extensions[3];
730fc3d0
VY		 185 sctp_paramhdr_t *auth_chunks = NULL,
186 *auth_hmacs = NULL;
1da177e4
LT		 187
188 /* RFC 2960 3.3.2 Initiation (INIT) (1)
189 *
190 * Note 1: The INIT chunks can contain multiple addresses that
191 * can be IPv4 and/or IPv6 in any combination.
192 */
193 retval = NULL;
194
195 /* Convert the provided bind address list to raw format. */
196 addrs = sctp_bind_addrs_to_raw(bp, &addrs_len, gfp);
197
198 init.init_tag = htonl(asoc->c.my_vtag);
199 init.a_rwnd = htonl(asoc->rwnd);
200 init.num_outbound_streams = htons(asoc->c.sinit_num_ostreams);
201 init.num_inbound_streams = htons(asoc->c.sinit_max_instreams);
202 init.initial_tsn = htonl(asoc->c.initial_tsn);
203
204 /* How many address types are needed? */
205 sp = sctp_sk(asoc->base.sk);
206 num_types = sp->pf->supported_addrs(sp, types);
207
208 chunksize = sizeof(init) + addrs_len + SCTP_SAT_LEN(num_types);
209 chunksize += sizeof(ecap_param);
131a47e3 210 if (sctp_prsctp_enable) {
1da177e4 211 chunksize += sizeof(prsctp_param);
131a47e3
VY		 212 extensions[num_ext] = SCTP_CID_FWD_TSN;
213 num_ext += 1;
214 }
215 /* ADDIP: Section 4.2.7:
216 * An implementation supporting this extension [ADDIP] MUST list
217 * the ASCONF,the ASCONF-ACK, and the AUTH chunks in its INIT and
218 * INIT-ACK parameters.
131a47e3
VY		 219 */
220 if (sctp_addip_enable) {
221 extensions[num_ext] = SCTP_CID_ASCONF;
222 extensions[num_ext+1] = SCTP_CID_ASCONF_ACK;
223 num_ext += 2;
224 }
225
1da177e4
LT		 226 chunksize += sizeof(aiparam);
227 chunksize += vparam_len;
228
730fc3d0
VY		 229 /* Account for AUTH related parameters */
230 if (sctp_auth_enable) {
231 /* Add random parameter length*/
232 chunksize += sizeof(asoc->c.auth_random);
233
234 /* Add HMACS parameter length if any were defined */
235 auth_hmacs = (sctp_paramhdr_t *)asoc->c.auth_hmacs;
236 if (auth_hmacs->length)
237 chunksize += ntohs(auth_hmacs->length);
238 else
239 auth_hmacs = NULL;
240
241 /* Add CHUNKS parameter length */
242 auth_chunks = (sctp_paramhdr_t *)asoc->c.auth_chunks;
243 if (auth_chunks->length)
244 chunksize += ntohs(auth_chunks->length);
245 else
246 auth_hmacs = NULL;
247
248 extensions[num_ext] = SCTP_CID_AUTH;
249 num_ext += 1;
250 }
251
131a47e3
VY		 252 /* If we have any extensions to report, account for that */
253 if (num_ext)
254 chunksize += sizeof(sctp_supported_ext_param_t) + num_ext;
255
1da177e4
LT		 256 /* RFC 2960 3.3.2 Initiation (INIT) (1)
257 *
258 * Note 3: An INIT chunk MUST NOT contain more than one Host
259 * Name address parameter. Moreover, the sender of the INIT
260 * MUST NOT combine any other address types with the Host Name
261 * address in the INIT. The receiver of INIT MUST ignore any
262 * other address types if the Host Name address parameter is
263 * present in the received INIT chunk.
264 *
265 * PLEASE DO NOT FIXME [This version does not support Host Name.]
266 */
267
268 retval = sctp_make_chunk(asoc, SCTP_CID_INIT, 0, chunksize);
269 if (!retval)
270 goto nodata;
271
272 retval->subh.init_hdr =
273 sctp_addto_chunk(retval, sizeof(init), &init);
274 retval->param_hdr.v =
275 sctp_addto_chunk(retval, addrs_len, addrs.v);
276
277 /* RFC 2960 3.3.2 Initiation (INIT) (1)
278 *
279 * Note 4: This parameter, when present, specifies all the
280 * address types the sending endpoint can support. The absence
281 * of this parameter indicates that the sending endpoint can
282 * support any address type.
283 */
284 sat.param_hdr.type = SCTP_PARAM_SUPPORTED_ADDRESS_TYPES;
285 sat.param_hdr.length = htons(SCTP_SAT_LEN(num_types));
286 sctp_addto_chunk(retval, sizeof(sat), &sat);
287 sctp_addto_chunk(retval, num_types * sizeof(__u16), &types);
288
289 sctp_addto_chunk(retval, sizeof(ecap_param), &ecap_param);
131a47e3
VY		 290
291 /* Add the supported extensions paramter. Be nice and add this
292 * fist before addiding the parameters for the extensions themselves
293 */
294 if (num_ext) {
295 ext_param.param_hdr.type = SCTP_PARAM_SUPPORTED_EXT;
296 ext_param.param_hdr.length =
297 htons(sizeof(sctp_supported_ext_param_t) + num_ext);
298 sctp_addto_chunk(retval, sizeof(sctp_supported_ext_param_t),
299 &ext_param);
300 sctp_addto_chunk(retval, num_ext, extensions);
301 }
302
1da177e4
LT		 303 if (sctp_prsctp_enable)
304 sctp_addto_chunk(retval, sizeof(prsctp_param), &prsctp_param);
131a47e3 305
0f3fffd8 306 aiparam.param_hdr.type = SCTP_PARAM_ADAPTATION_LAYER_IND;
1da177e4 307 aiparam.param_hdr.length = htons(sizeof(aiparam));
0f3fffd8 308 aiparam.adaptation_ind = htonl(sp->adaptation_ind);
1da177e4 309 sctp_addto_chunk(retval, sizeof(aiparam), &aiparam);
131a47e3 310
730fc3d0
VY		 311 /* Add SCTP-AUTH chunks to the parameter list */
312 if (sctp_auth_enable) {
313 sctp_addto_chunk(retval, sizeof(asoc->c.auth_random),
314 asoc->c.auth_random);
315 if (auth_hmacs)
316 sctp_addto_chunk(retval, ntohs(auth_hmacs->length),
317 auth_hmacs);
318 if (auth_chunks)
319 sctp_addto_chunk(retval, ntohs(auth_chunks->length),
320 auth_chunks);
321 }
1da177e4 322nodata:
a51482bd 323 kfree(addrs.v);
1da177e4
LT		 324 return retval;
325}
326
327struct sctp_chunk *sctp_make_init_ack(const struct sctp_association *asoc,
328 const struct sctp_chunk *chunk,
dd0fc66f 329 gfp_t gfp, int unkparam_len)
1da177e4
LT		 330{
331 sctp_inithdr_t initack;
332 struct sctp_chunk *retval;
333 union sctp_params addrs;
334 int addrs_len;
335 sctp_cookie_param_t *cookie;
336 int cookie_len;
337 size_t chunksize;
0f3fffd8 338 sctp_adaptation_ind_param_t aiparam;
131a47e3
VY		 339 sctp_supported_ext_param_t ext_param;
340 int num_ext = 0;
341 __u8 extensions[3];
730fc3d0
VY		 342 sctp_paramhdr_t *auth_chunks = NULL,
343 *auth_hmacs = NULL,
344 *auth_random = NULL;
1da177e4
LT		 345
346 retval = NULL;
347
348 /* Note: there may be no addresses to embed. */
349 addrs = sctp_bind_addrs_to_raw(&asoc->base.bind_addr, &addrs_len, gfp);
350
351 initack.init_tag = htonl(asoc->c.my_vtag);
352 initack.a_rwnd = htonl(asoc->rwnd);
353 initack.num_outbound_streams = htons(asoc->c.sinit_num_ostreams);
354 initack.num_inbound_streams = htons(asoc->c.sinit_max_instreams);
355 initack.initial_tsn = htonl(asoc->c.initial_tsn);
356
357 /* FIXME: We really ought to build the cookie right
358 * into the packet instead of allocating more fresh memory.
359 */
360 cookie = sctp_pack_cookie(asoc->ep, asoc, chunk, &cookie_len,
361 addrs.v, addrs_len);
362 if (!cookie)
363 goto nomem_cookie;
364
365 /* Calculate the total size of allocation, include the reserved
366 * space for reporting unknown parameters if it is specified.
367 */
368 chunksize = sizeof(initack) + addrs_len + cookie_len + unkparam_len;
369
d808ad9a 370 /* Tell peer that we'll do ECN only if peer advertised such cap. */
1da177e4
LT		 371 if (asoc->peer.ecn_capable)
372 chunksize += sizeof(ecap_param);
373
d808ad9a 374 /* Tell peer that we'll do PR-SCTP only if peer advertised. */
131a47e3 375 if (asoc->peer.prsctp_capable) {
1da177e4 376 chunksize += sizeof(prsctp_param);
131a47e3
VY		 377 extensions[num_ext] = SCTP_CID_FWD_TSN;
378 num_ext += 1;
379 }
1da177e4 380
131a47e3
VY		 381 if (sctp_addip_enable) {
382 extensions[num_ext] = SCTP_CID_ASCONF;
383 extensions[num_ext+1] = SCTP_CID_ASCONF_ACK;
384 num_ext += 2;
385 }
386
387 chunksize += sizeof(ext_param) + num_ext;
1da177e4
LT		 388 chunksize += sizeof(aiparam);
389
730fc3d0
VY		 390 if (asoc->peer.auth_capable) {
391 auth_random = (sctp_paramhdr_t *)asoc->c.auth_random;
392 chunksize += ntohs(auth_random->length);
393
394 auth_hmacs = (sctp_paramhdr_t *)asoc->c.auth_hmacs;
395 if (auth_hmacs->length)
396 chunksize += ntohs(auth_hmacs->length);
397 else
398 auth_hmacs = NULL;
399
400 auth_chunks = (sctp_paramhdr_t *)asoc->c.auth_chunks;
401 if (auth_chunks->length)
402 chunksize += ntohs(auth_chunks->length);
403 else
404 auth_chunks = NULL;
405
406 extensions[num_ext] = SCTP_CID_AUTH;
407 num_ext += 1;
408 }
409
1da177e4
LT		 410 /* Now allocate and fill out the chunk. */
411 retval = sctp_make_chunk(asoc, SCTP_CID_INIT_ACK, 0, chunksize);
412 if (!retval)
413 goto nomem_chunk;
414
415 /* Per the advice in RFC 2960 6.4, send this reply to
416 * the source of the INIT packet.
417 */
418 retval->transport = chunk->transport;
419 retval->subh.init_hdr =
420 sctp_addto_chunk(retval, sizeof(initack), &initack);
421 retval->param_hdr.v = sctp_addto_chunk(retval, addrs_len, addrs.v);
422 sctp_addto_chunk(retval, cookie_len, cookie);
423 if (asoc->peer.ecn_capable)
424 sctp_addto_chunk(retval, sizeof(ecap_param), &ecap_param);
131a47e3
VY		 425 if (num_ext) {
426 ext_param.param_hdr.type = SCTP_PARAM_SUPPORTED_EXT;
427 ext_param.param_hdr.length =
428 htons(sizeof(sctp_supported_ext_param_t) + num_ext);
429 sctp_addto_chunk(retval, sizeof(sctp_supported_ext_param_t),
430 &ext_param);
431 sctp_addto_chunk(retval, num_ext, extensions);
432 }
1da177e4
LT		 433 if (asoc->peer.prsctp_capable)
434 sctp_addto_chunk(retval, sizeof(prsctp_param), &prsctp_param);
435
0f3fffd8 436 aiparam.param_hdr.type = SCTP_PARAM_ADAPTATION_LAYER_IND;
1da177e4 437 aiparam.param_hdr.length = htons(sizeof(aiparam));
0f3fffd8 438 aiparam.adaptation_ind = htonl(sctp_sk(asoc->base.sk)->adaptation_ind);
1da177e4
LT		 439 sctp_addto_chunk(retval, sizeof(aiparam), &aiparam);
440
730fc3d0
VY		 441 if (asoc->peer.auth_capable) {
442 sctp_addto_chunk(retval, ntohs(auth_random->length),
443 auth_random);
444 if (auth_hmacs)
445 sctp_addto_chunk(retval, ntohs(auth_hmacs->length),
446 auth_hmacs);
447 if (auth_chunks)
448 sctp_addto_chunk(retval, ntohs(auth_chunks->length),
449 auth_chunks);
450 }
451
1da177e4
LT		 452 /* We need to remove the const qualifier at this point. */
453 retval->asoc = (struct sctp_association *) asoc;
454
455 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
456 *
457 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
458 * HEARTBEAT ACK, * etc.) to the same destination transport
459 * address from which it received the DATA or control chunk
460 * to which it is replying.
461 *
462 * [INIT ACK back to where the INIT came from.]
463 */
464 if (chunk)
465 retval->transport = chunk->transport;
466
467nomem_chunk:
468 kfree(cookie);
469nomem_cookie:
a51482bd 470 kfree(addrs.v);
1da177e4
LT		 471 return retval;
472}
473
474/* 3.3.11 Cookie Echo (COOKIE ECHO) (10):
475 *
476 * This chunk is used only during the initialization of an association.
477 * It is sent by the initiator of an association to its peer to complete
478 * the initialization process. This chunk MUST precede any DATA chunk
479 * sent within the association, but MAY be bundled with one or more DATA
480 * chunks in the same packet.
481 *
482 * 0 1 2 3
483 * 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
484 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
485 * | Type = 10 |Chunk Flags | Length |
486 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
487 * / Cookie /
488 * \ \
489 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
490 *
491 * Chunk Flags: 8 bit
492 *
493 * Set to zero on transmit and ignored on receipt.
494 *
495 * Length: 16 bits (unsigned integer)
496 *
497 * Set to the size of the chunk in bytes, including the 4 bytes of
498 * the chunk header and the size of the Cookie.
499 *
500 * Cookie: variable size
501 *
502 * This field must contain the exact cookie received in the
503 * State Cookie parameter from the previous INIT ACK.
504 *
505 * An implementation SHOULD make the cookie as small as possible
506 * to insure interoperability.
507 */
508struct sctp_chunk *sctp_make_cookie_echo(const struct sctp_association *asoc,
509 const struct sctp_chunk *chunk)
510{
511 struct sctp_chunk *retval;
512 void *cookie;
513 int cookie_len;
514
515 cookie = asoc->peer.cookie;
516 cookie_len = asoc->peer.cookie_len;
517
518 /* Build a cookie echo chunk. */
519 retval = sctp_make_chunk(asoc, SCTP_CID_COOKIE_ECHO, 0, cookie_len);
520 if (!retval)
521 goto nodata;
522 retval->subh.cookie_hdr =
523 sctp_addto_chunk(retval, cookie_len, cookie);
524
525 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
526 *
527 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
528 * HEARTBEAT ACK, * etc.) to the same destination transport
529 * address from which it * received the DATA or control chunk
530 * to which it is replying.
531 *
532 * [COOKIE ECHO back to where the INIT ACK came from.]
533 */
534 if (chunk)
535 retval->transport = chunk->transport;
536
537nodata:
538 return retval;
539}
540
541/* 3.3.12 Cookie Acknowledgement (COOKIE ACK) (11):
542 *
543 * This chunk is used only during the initialization of an
544 * association. It is used to acknowledge the receipt of a COOKIE
545 * ECHO chunk. This chunk MUST precede any DATA or SACK chunk sent
546 * within the association, but MAY be bundled with one or more DATA
547 * chunks or SACK chunk in the same SCTP packet.
548 *
549 * 0 1 2 3
550 * 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
551 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
552 * | Type = 11 |Chunk Flags | Length = 4 |
553 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
554 *
555 * Chunk Flags: 8 bits
556 *
557 * Set to zero on transmit and ignored on receipt.
558 */
559struct sctp_chunk *sctp_make_cookie_ack(const struct sctp_association *asoc,
560 const struct sctp_chunk *chunk)
561{
562 struct sctp_chunk *retval;
563
564 retval = sctp_make_chunk(asoc, SCTP_CID_COOKIE_ACK, 0, 0);
565
566 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
567 *
568 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
569 * HEARTBEAT ACK, * etc.) to the same destination transport
570 * address from which it * received the DATA or control chunk
571 * to which it is replying.
572 *
573 * [COOKIE ACK back to where the COOKIE ECHO came from.]
574 */
575 if (retval && chunk)
576 retval->transport = chunk->transport;
577
578 return retval;
579}
580
581/*
582 * Appendix A: Explicit Congestion Notification:
583 * CWR:
584 *
585 * RFC 2481 details a specific bit for a sender to send in the header of
586 * its next outbound TCP segment to indicate to its peer that it has
587 * reduced its congestion window. This is termed the CWR bit. For
588 * SCTP the same indication is made by including the CWR chunk.
589 * This chunk contains one data element, i.e. the TSN number that
590 * was sent in the ECNE chunk. This element represents the lowest
591 * TSN number in the datagram that was originally marked with the
592 * CE bit.
593 *
594 * 0 1 2 3
595 * 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
596 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
597 * | Chunk Type=13 | Flags=00000000| Chunk Length = 8 |
598 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
599 * | Lowest TSN Number |
600 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
601 *
602 * Note: The CWR is considered a Control chunk.
603 */
604struct sctp_chunk *sctp_make_cwr(const struct sctp_association *asoc,
605 const __u32 lowest_tsn,
606 const struct sctp_chunk *chunk)
607{
608 struct sctp_chunk *retval;
609 sctp_cwrhdr_t cwr;
610
611 cwr.lowest_tsn = htonl(lowest_tsn);
612 retval = sctp_make_chunk(asoc, SCTP_CID_ECN_CWR, 0,
613 sizeof(sctp_cwrhdr_t));
614
615 if (!retval)
616 goto nodata;
617
618 retval->subh.ecn_cwr_hdr =
619 sctp_addto_chunk(retval, sizeof(cwr), &cwr);
620
621 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
622 *
623 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
624 * HEARTBEAT ACK, * etc.) to the same destination transport
625 * address from which it * received the DATA or control chunk
626 * to which it is replying.
627 *
628 * [Report a reduced congestion window back to where the ECNE
629 * came from.]
630 */
631 if (chunk)
632 retval->transport = chunk->transport;
633
634nodata:
635 return retval;
636}
637
638/* Make an ECNE chunk. This is a congestion experienced report. */
639struct sctp_chunk *sctp_make_ecne(const struct sctp_association *asoc,
640 const __u32 lowest_tsn)
641{
642 struct sctp_chunk *retval;
643 sctp_ecnehdr_t ecne;
644
645 ecne.lowest_tsn = htonl(lowest_tsn);
646 retval = sctp_make_chunk(asoc, SCTP_CID_ECN_ECNE, 0,
647 sizeof(sctp_ecnehdr_t));
648 if (!retval)
649 goto nodata;
650 retval->subh.ecne_hdr =
651 sctp_addto_chunk(retval, sizeof(ecne), &ecne);
652
653nodata:
654 return retval;
655}
656
657/* Make a DATA chunk for the given association from the provided
658 * parameters. However, do not populate the data payload.
659 */
660struct sctp_chunk *sctp_make_datafrag_empty(struct sctp_association *asoc,
661 const struct sctp_sndrcvinfo *sinfo,
662 int data_len, __u8 flags, __u16 ssn)
663{
664 struct sctp_chunk *retval;
665 struct sctp_datahdr dp;
666 int chunk_len;
667
668 /* We assign the TSN as LATE as possible, not here when
669 * creating the chunk.
670 */
671 dp.tsn = 0;
672 dp.stream = htons(sinfo->sinfo_stream);
673 dp.ppid = sinfo->sinfo_ppid;
674
675 /* Set the flags for an unordered send. */
eaa5c54d 676 if (sinfo->sinfo_flags & SCTP_UNORDERED) {
1da177e4
LT		 677 flags |= SCTP_DATA_UNORDERED;
678 dp.ssn = 0;
679 } else
680 dp.ssn = htons(ssn);
681
682 chunk_len = sizeof(dp) + data_len;
683 retval = sctp_make_chunk(asoc, SCTP_CID_DATA, flags, chunk_len);
684 if (!retval)
685 goto nodata;
686
687 retval->subh.data_hdr = sctp_addto_chunk(retval, sizeof(dp), &dp);
688 memcpy(&retval->sinfo, sinfo, sizeof(struct sctp_sndrcvinfo));
689
690nodata:
691 return retval;
692}
693
694/* Create a selective ackowledgement (SACK) for the given
695 * association. This reports on which TSN's we've seen to date,
696 * including duplicates and gaps.
697 */
698struct sctp_chunk *sctp_make_sack(const struct sctp_association *asoc)
699{
700 struct sctp_chunk *retval;
701 struct sctp_sackhdr sack;
702 int len;
703 __u32 ctsn;
704 __u16 num_gabs, num_dup_tsns;
705 struct sctp_tsnmap *map = (struct sctp_tsnmap *)&asoc->peer.tsn_map;
706
707 ctsn = sctp_tsnmap_get_ctsn(map);
708 SCTP_DEBUG_PRINTK("sackCTSNAck sent: 0x%x.\n", ctsn);
709
710 /* How much room is needed in the chunk? */
711 num_gabs = sctp_tsnmap_num_gabs(map);
712 num_dup_tsns = sctp_tsnmap_num_dups(map);
713
714 /* Initialize the SACK header. */
715 sack.cum_tsn_ack = htonl(ctsn);
716 sack.a_rwnd = htonl(asoc->a_rwnd);
717 sack.num_gap_ack_blocks = htons(num_gabs);
718 sack.num_dup_tsns = htons(num_dup_tsns);
719
720 len = sizeof(sack)
721 + sizeof(struct sctp_gap_ack_block) * num_gabs
722 + sizeof(__u32) * num_dup_tsns;
723
724 /* Create the chunk. */
725 retval = sctp_make_chunk(asoc, SCTP_CID_SACK, 0, len);
726 if (!retval)
727 goto nodata;
728
729 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
730 *
731 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
732 * HEARTBEAT ACK, etc.) to the same destination transport
733 * address from which it received the DATA or control chunk to
734 * which it is replying. This rule should also be followed if
735 * the endpoint is bundling DATA chunks together with the
736 * reply chunk.
737 *
738 * However, when acknowledging multiple DATA chunks received
739 * in packets from different source addresses in a single
740 * SACK, the SACK chunk may be transmitted to one of the
741 * destination transport addresses from which the DATA or
742 * control chunks being acknowledged were received.
743 *
744 * [BUG: We do not implement the following paragraph.
745 * Perhaps we should remember the last transport we used for a
746 * SACK and avoid that (if possible) if we have seen any
747 * duplicates. --piggy]
748 *
749 * When a receiver of a duplicate DATA chunk sends a SACK to a
750 * multi- homed endpoint it MAY be beneficial to vary the
751 * destination address and not use the source address of the
752 * DATA chunk. The reason being that receiving a duplicate
753 * from a multi-homed endpoint might indicate that the return
754 * path (as specified in the source address of the DATA chunk)
755 * for the SACK is broken.
756 *
757 * [Send to the address from which we last received a DATA chunk.]
758 */
759 retval->transport = asoc->peer.last_data_from;
760
761 retval->subh.sack_hdr =
762 sctp_addto_chunk(retval, sizeof(sack), &sack);
763
764 /* Add the gap ack block information. */
765 if (num_gabs)
766 sctp_addto_chunk(retval, sizeof(__u32) * num_gabs,
767 sctp_tsnmap_get_gabs(map));
768
769 /* Add the duplicate TSN information. */
770 if (num_dup_tsns)
771 sctp_addto_chunk(retval, sizeof(__u32) * num_dup_tsns,
772 sctp_tsnmap_get_dups(map));
773
774nodata:
775 return retval;
776}
777
778/* Make a SHUTDOWN chunk. */
779struct sctp_chunk *sctp_make_shutdown(const struct sctp_association *asoc,
780 const struct sctp_chunk *chunk)
781{
782 struct sctp_chunk *retval;
783 sctp_shutdownhdr_t shut;
784 __u32 ctsn;
785
786 ctsn = sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map);
787 shut.cum_tsn_ack = htonl(ctsn);
788
789 retval = sctp_make_chunk(asoc, SCTP_CID_SHUTDOWN, 0,
790 sizeof(sctp_shutdownhdr_t));
791 if (!retval)
792 goto nodata;
793
794 retval->subh.shutdown_hdr =
795 sctp_addto_chunk(retval, sizeof(shut), &shut);
796
797 if (chunk)
798 retval->transport = chunk->transport;
799nodata:
800 return retval;
801}
802
803struct sctp_chunk *sctp_make_shutdown_ack(const struct sctp_association *asoc,
804 const struct sctp_chunk *chunk)
805{
806 struct sctp_chunk *retval;
807
808 retval = sctp_make_chunk(asoc, SCTP_CID_SHUTDOWN_ACK, 0, 0);
809
810 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
811 *
812 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
813 * HEARTBEAT ACK, * etc.) to the same destination transport
814 * address from which it * received the DATA or control chunk
815 * to which it is replying.
816 *
817 * [ACK back to where the SHUTDOWN came from.]
818 */
819 if (retval && chunk)
820 retval->transport = chunk->transport;
821
822 return retval;
823}
824
825struct sctp_chunk *sctp_make_shutdown_complete(
826 const struct sctp_association *asoc,
827 const struct sctp_chunk *chunk)
828{
829 struct sctp_chunk *retval;
830 __u8 flags = 0;
831
047a2428
JF		 832 /* Set the T-bit if we have no association (vtag will be
833 * reflected)
834 */
1da177e4
LT		 835 flags |= asoc ? 0 : SCTP_CHUNK_FLAG_T;
836
837 retval = sctp_make_chunk(asoc, SCTP_CID_SHUTDOWN_COMPLETE, flags, 0);
838
839 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
840 *
841 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
842 * HEARTBEAT ACK, * etc.) to the same destination transport
843 * address from which it * received the DATA or control chunk
844 * to which it is replying.
845 *
846 * [Report SHUTDOWN COMPLETE back to where the SHUTDOWN ACK
847 * came from.]
848 */
849 if (retval && chunk)
850 retval->transport = chunk->transport;
851
d808ad9a 852 return retval;
1da177e4
LT		 853}
854
855/* Create an ABORT. Note that we set the T bit if we have no
047a2428 856 * association, except when responding to an INIT (sctpimpguide 2.41).
1da177e4
LT		 857 */
858struct sctp_chunk *sctp_make_abort(const struct sctp_association *asoc,
859 const struct sctp_chunk *chunk,
860 const size_t hint)
861{
862 struct sctp_chunk *retval;
863 __u8 flags = 0;
864
047a2428
JF		 865 /* Set the T-bit if we have no association and 'chunk' is not
866 * an INIT (vtag will be reflected).
867 */
868 if (!asoc) {
869 if (chunk && chunk->chunk_hdr &&
870 chunk->chunk_hdr->type == SCTP_CID_INIT)
871 flags = 0;
872 else
873 flags = SCTP_CHUNK_FLAG_T;
874 }
1da177e4
LT		 875
876 retval = sctp_make_chunk(asoc, SCTP_CID_ABORT, flags, hint);
877
878 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
879 *
880 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
881 * HEARTBEAT ACK, * etc.) to the same destination transport
882 * address from which it * received the DATA or control chunk
883 * to which it is replying.
884 *
885 * [ABORT back to where the offender came from.]
886 */
887 if (retval && chunk)
888 retval->transport = chunk->transport;
889
890 return retval;
891}
892
893/* Helper to create ABORT with a NO_USER_DATA error. */
894struct sctp_chunk *sctp_make_abort_no_data(
895 const struct sctp_association *asoc,
896 const struct sctp_chunk *chunk, __u32 tsn)
897{
898 struct sctp_chunk *retval;
9f81bcd9 899 __be32 payload;
1da177e4
LT		 900
901 retval = sctp_make_abort(asoc, chunk, sizeof(sctp_errhdr_t)
902 + sizeof(tsn));
903
904 if (!retval)
905 goto no_mem;
906
907 /* Put the tsn back into network byte order. */
908 payload = htonl(tsn);
00f1c2df
WY		 909 sctp_init_cause(retval, SCTP_ERROR_NO_DATA, sizeof(payload));
910 sctp_addto_chunk(retval, sizeof(payload), (const void *)&payload);
1da177e4
LT		 911
912 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
913 *
914 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
915 * HEARTBEAT ACK, * etc.) to the same destination transport
916 * address from which it * received the DATA or control chunk
917 * to which it is replying.
918 *
919 * [ABORT back to where the offender came from.]
920 */
921 if (chunk)
922 retval->transport = chunk->transport;
923
924no_mem:
925 return retval;
926}
927
928/* Helper to create ABORT with a SCTP_ERROR_USER_ABORT error. */
929struct sctp_chunk *sctp_make_abort_user(const struct sctp_association *asoc,
c164a9ba
SS		 930 const struct msghdr *msg,
931 size_t paylen)
1da177e4
LT		 932{
933 struct sctp_chunk *retval;
c164a9ba
SS		 934 void *payload = NULL;
935 int err;
1da177e4 936
c164a9ba 937 retval = sctp_make_abort(asoc, NULL, sizeof(sctp_errhdr_t) + paylen);
1da177e4
LT		 938 if (!retval)
939 goto err_chunk;
940
941 if (paylen) {
942 /* Put the msg_iov together into payload. */
c164a9ba 943 payload = kmalloc(paylen, GFP_KERNEL);
1da177e4
LT		 944 if (!payload)
945 goto err_payload;
c164a9ba
SS		 946
947 err = memcpy_fromiovec(payload, msg->msg_iov, paylen);
948 if (err < 0)
949 goto err_copy;
1da177e4
LT		 950 }
951
00f1c2df
WY		 952 sctp_init_cause(retval, SCTP_ERROR_USER_ABORT, paylen);
953 sctp_addto_chunk(retval, paylen, payload);
1da177e4
LT		 954
955 if (paylen)
956 kfree(payload);
957
958 return retval;
959
960err_copy:
961 kfree(payload);
962err_payload:
963 sctp_chunk_free(retval);
964 retval = NULL;
965err_chunk:
966 return retval;
967}
968
5c94bf86
AB		 969/* Append bytes to the end of a parameter. Will panic if chunk is not big
970 * enough.
971 */
972static void *sctp_addto_param(struct sctp_chunk *chunk, int len,
973 const void *data)
974{
975 void *target;
976 int chunklen = ntohs(chunk->chunk_hdr->length);
977
978 target = skb_put(chunk->skb, len);
979
980 memcpy(target, data, len);
981
982 /* Adjust the chunk length field. */
983 chunk->chunk_hdr->length = htons(chunklen + len);
984 chunk->chunk_end = skb_tail_pointer(chunk->skb);
985
986 return target;
987}
988
d808ad9a 989/* Make an ABORT chunk with a PROTOCOL VIOLATION cause code. */
1da177e4
LT		 990struct sctp_chunk *sctp_make_abort_violation(
991 const struct sctp_association *asoc,
992 const struct sctp_chunk *chunk,
993 const __u8 *payload,
994 const size_t paylen)
995{
996 struct sctp_chunk *retval;
997 struct sctp_paramhdr phdr;
998
999 retval = sctp_make_abort(asoc, chunk, sizeof(sctp_errhdr_t) + paylen
00f1c2df 1000 + sizeof(sctp_paramhdr_t));
1da177e4
LT		 1001 if (!retval)
1002 goto end;
1003
00f1c2df
WY		 1004 sctp_init_cause(retval, SCTP_ERROR_PROTO_VIOLATION, paylen
1005 + sizeof(sctp_paramhdr_t));
1da177e4
LT		 1006
1007 phdr.type = htons(chunk->chunk_hdr->type);
1008 phdr.length = chunk->chunk_hdr->length;
00f1c2df
WY		 1009 sctp_addto_chunk(retval, paylen, payload);
1010 sctp_addto_param(retval, sizeof(sctp_paramhdr_t), &phdr);
1da177e4
LT		 1011
1012end:
1013 return retval;
1014}
1015
1016/* Make a HEARTBEAT chunk. */
1017struct sctp_chunk *sctp_make_heartbeat(const struct sctp_association *asoc,
1018 const struct sctp_transport *transport,
1019 const void *payload, const size_t paylen)
1020{
1021 struct sctp_chunk *retval = sctp_make_chunk(asoc, SCTP_CID_HEARTBEAT,
1022 0, paylen);
1023
1024 if (!retval)
1025 goto nodata;
1026
1027 /* Cast away the 'const', as this is just telling the chunk
1028 * what transport it belongs to.
1029 */
1030 retval->transport = (struct sctp_transport *) transport;
1031 retval->subh.hbs_hdr = sctp_addto_chunk(retval, paylen, payload);
1032
1033nodata:
1034 return retval;
1035}
1036
1037struct sctp_chunk *sctp_make_heartbeat_ack(const struct sctp_association *asoc,
1038 const struct sctp_chunk *chunk,
1039 const void *payload, const size_t paylen)
1040{
1041 struct sctp_chunk *retval;
1042
1043 retval = sctp_make_chunk(asoc, SCTP_CID_HEARTBEAT_ACK, 0, paylen);
1044 if (!retval)
1045 goto nodata;
1046
1047 retval->subh.hbs_hdr = sctp_addto_chunk(retval, paylen, payload);
1048
1049 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
1050 *
1051 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
1052 * HEARTBEAT ACK, * etc.) to the same destination transport
1053 * address from which it * received the DATA or control chunk
1054 * to which it is replying.
1055 *
1056 * [HBACK back to where the HEARTBEAT came from.]
1057 */
1058 if (chunk)
1059 retval->transport = chunk->transport;
1060
1061nodata:
1062 return retval;
1063}
1064
1065/* Create an Operation Error chunk with the specified space reserved.
1066 * This routine can be used for containing multiple causes in the chunk.
1067 */
1068static struct sctp_chunk *sctp_make_op_error_space(
1069 const struct sctp_association *asoc,
1070 const struct sctp_chunk *chunk,
1071 size_t size)
1072{
1073 struct sctp_chunk *retval;
1074
1075 retval = sctp_make_chunk(asoc, SCTP_CID_ERROR, 0,
1076 sizeof(sctp_errhdr_t) + size);
1077 if (!retval)
1078 goto nodata;
1079
1080 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
1081 *
1082 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
1083 * HEARTBEAT ACK, etc.) to the same destination transport
1084 * address from which it received the DATA or control chunk
1085 * to which it is replying.
1086 *
1087 */
1088 if (chunk)
1089 retval->transport = chunk->transport;
1090
1091nodata:
1092 return retval;
1093}
1094
1095/* Create an Operation Error chunk. */
1096struct sctp_chunk *sctp_make_op_error(const struct sctp_association *asoc,
1097 const struct sctp_chunk *chunk,
63706c5c 1098 __be16 cause_code, const void *payload,
1da177e4
LT		 1099 size_t paylen)
1100{
1101 struct sctp_chunk *retval;
1102
1103 retval = sctp_make_op_error_space(asoc, chunk, paylen);
1104 if (!retval)
1105 goto nodata;
1106
00f1c2df
WY		 1107 sctp_init_cause(retval, cause_code, paylen);
1108 sctp_addto_chunk(retval, paylen, payload);
1da177e4
LT		 1109
1110nodata:
1111 return retval;
1112}
1113
4cd57c80
VY		 1114struct sctp_chunk *sctp_make_auth(const struct sctp_association *asoc)
1115{
1116 struct sctp_chunk *retval;
1117 struct sctp_hmac *hmac_desc;
1118 struct sctp_authhdr auth_hdr;
1119 __u8 *hmac;
1120
1121 /* Get the first hmac that the peer told us to use */
1122 hmac_desc = sctp_auth_asoc_get_hmac(asoc);
1123 if (unlikely(!hmac_desc))
1124 return NULL;
1125
1126 retval = sctp_make_chunk(asoc, SCTP_CID_AUTH, 0,
1127 hmac_desc->hmac_len + sizeof(sctp_authhdr_t));
1128 if (!retval)
1129 return NULL;
1130
1131 auth_hdr.hmac_id = htons(hmac_desc->hmac_id);
1132 auth_hdr.shkey_id = htons(asoc->active_key_id);
1133
1134 retval->subh.auth_hdr = sctp_addto_chunk(retval, sizeof(sctp_authhdr_t),
1135 &auth_hdr);
1136
1137 hmac = skb_put(retval->skb, hmac_desc->hmac_len);
1138 memset(hmac, 0, hmac_desc->hmac_len);
1139
1140 /* Adjust the chunk header to include the empty MAC */
1141 retval->chunk_hdr->length =
1142 htons(ntohs(retval->chunk_hdr->length) + hmac_desc->hmac_len);
1143 retval->chunk_end = skb_tail_pointer(retval->skb);
1144
1145 return retval;
1146}
1147
1148
1da177e4
LT		 1149/********************************************************************
1150 * 2nd Level Abstractions
1151 ********************************************************************/
1152
1153/* Turn an skb into a chunk.
1154 * FIXME: Eventually move the structure directly inside the skb->cb[].
1155 */
1156struct sctp_chunk *sctp_chunkify(struct sk_buff *skb,
1157 const struct sctp_association *asoc,
1158 struct sock *sk)
1159{
1160 struct sctp_chunk *retval;
1161
c3762229 1162 retval = kmem_cache_zalloc(sctp_chunk_cachep, GFP_ATOMIC);
1da177e4
LT		 1163
1164 if (!retval)
1165 goto nodata;
1da177e4
LT		 1166
1167 if (!sk) {
1168 SCTP_DEBUG_PRINTK("chunkifying skb %p w/o an sk\n", skb);
1169 }
1170
79af02c2 1171 INIT_LIST_HEAD(&retval->list);
1da177e4
LT		 1172 retval->skb = skb;
1173 retval->asoc = (struct sctp_association *)asoc;
1174 retval->resent = 0;
1175 retval->has_tsn = 0;
1176 retval->has_ssn = 0;
1177 retval->rtt_in_progress = 0;
1178 retval->sent_at = 0;
1179 retval->singleton = 1;
1180 retval->end_of_packet = 0;
1181 retval->ecn_ce_done = 0;
1182 retval->pdiscard = 0;
1183
1184 /* sctpimpguide-05.txt Section 2.8.2
1185 * M1) Each time a new DATA chunk is transmitted
1186 * set the 'TSN.Missing.Report' count for that TSN to 0. The
1187 * 'TSN.Missing.Report' count will be used to determine missing chunks
1188 * and when to fast retransmit.
1189 */
1190 retval->tsn_missing_report = 0;
1191 retval->tsn_gap_acked = 0;
1192 retval->fast_retransmit = 0;
1193
1194 /* If this is a fragmented message, track all fragments
1195 * of the message (for SEND_FAILED).
1196 */
1197 retval->msg = NULL;
1198
1199 /* Polish the bead hole. */
1200 INIT_LIST_HEAD(&retval->transmitted_list);
1201 INIT_LIST_HEAD(&retval->frag_list);
1202 SCTP_DBG_OBJCNT_INC(chunk);
1203 atomic_set(&retval->refcnt, 1);
1204
1205nodata:
1206 return retval;
1207}
1208
1209/* Set chunk->source and dest based on the IP header in chunk->skb. */
1210void sctp_init_addrs(struct sctp_chunk *chunk, union sctp_addr *src,
1211 union sctp_addr *dest)
1212{
f235fca3 1213 memcpy(&chunk->source, src, sizeof(union sctp_addr));
16b0a030 1214 memcpy(&chunk->dest, dest, sizeof(union sctp_addr));
1da177e4
LT		 1215}
1216
1217/* Extract the source address from a chunk. */
1218const union sctp_addr *sctp_source(const struct sctp_chunk *chunk)
1219{
1220 /* If we have a known transport, use that. */
1221 if (chunk->transport) {
6a1e5f33 1222 return &chunk->transport->ipaddr;
1da177e4
LT		 1223 } else {
1224 /* Otherwise, extract it from the IP header. */
6a1e5f33 1225 return &chunk->source;
1da177e4
LT		 1226 }
1227}
1228
1229/* Create a new chunk, setting the type and flags headers from the
1230 * arguments, reserving enough space for a 'paylen' byte payload.
1231 */
1232SCTP_STATIC
1233struct sctp_chunk *sctp_make_chunk(const struct sctp_association *asoc,
1234 __u8 type, __u8 flags, int paylen)
1235{
1236 struct sctp_chunk *retval;
1237 sctp_chunkhdr_t *chunk_hdr;
1238 struct sk_buff *skb;
1239 struct sock *sk;
1240
1241 /* No need to allocate LL here, as this is only a chunk. */
1242 skb = alloc_skb(WORD_ROUND(sizeof(sctp_chunkhdr_t) + paylen),
1243 GFP_ATOMIC);
1244 if (!skb)
1245 goto nodata;
1246
1247 /* Make room for the chunk header. */
1248 chunk_hdr = (sctp_chunkhdr_t *)skb_put(skb, sizeof(sctp_chunkhdr_t));
1249 chunk_hdr->type = type;
1250 chunk_hdr->flags = flags;
1251 chunk_hdr->length = htons(sizeof(sctp_chunkhdr_t));
1252
1253 sk = asoc ? asoc->base.sk : NULL;
1254 retval = sctp_chunkify(skb, asoc, sk);
1255 if (!retval) {
1256 kfree_skb(skb);
1257 goto nodata;
1258 }
1259
1260 retval->chunk_hdr = chunk_hdr;
1261 retval->chunk_end = ((__u8 *)chunk_hdr) + sizeof(struct sctp_chunkhdr);
1262
4cd57c80
VY		 1263 /* Determine if the chunk needs to be authenticated */
1264 if (sctp_auth_send_cid(type, asoc))
1265 retval->auth = 1;
1266
1da177e4
LT		 1267 /* Set the skb to the belonging sock for accounting. */
1268 skb->sk = sk;
1269
1270 return retval;
1271nodata:
1272 return NULL;
1273}
1274
1275
1276/* Release the memory occupied by a chunk. */
1277static void sctp_chunk_destroy(struct sctp_chunk *chunk)
1278{
1279 /* Free the chunk skb data and the SCTP_chunk stub itself. */
1280 dev_kfree_skb(chunk->skb);
1281
1282 SCTP_DBG_OBJCNT_DEC(chunk);
1283 kmem_cache_free(sctp_chunk_cachep, chunk);
1284}
1285
1286/* Possibly, free the chunk. */
1287void sctp_chunk_free(struct sctp_chunk *chunk)
1288{
79af02c2 1289 BUG_ON(!list_empty(&chunk->list));
1da177e4
LT		 1290 list_del_init(&chunk->transmitted_list);
1291
1292 /* Release our reference on the message tracker. */
1293 if (chunk->msg)
1294 sctp_datamsg_put(chunk->msg);
1295
1296 sctp_chunk_put(chunk);
1297}
1298
1299/* Grab a reference to the chunk. */
1300void sctp_chunk_hold(struct sctp_chunk *ch)
1301{
1302 atomic_inc(&ch->refcnt);
1303}
1304
1305/* Release a reference to the chunk. */
1306void sctp_chunk_put(struct sctp_chunk *ch)
1307{
1308 if (atomic_dec_and_test(&ch->refcnt))
1309 sctp_chunk_destroy(ch);
1310}
1311
1312/* Append bytes to the end of a chunk. Will panic if chunk is not big
1313 * enough.
1314 */
1315void *sctp_addto_chunk(struct sctp_chunk *chunk, int len, const void *data)
1316{
1317 void *target;
1318 void *padding;
1319 int chunklen = ntohs(chunk->chunk_hdr->length);
8d614ade 1320 int padlen = WORD_ROUND(chunklen) - chunklen;
1da177e4
LT		 1321
1322 padding = skb_put(chunk->skb, padlen);
1323 target = skb_put(chunk->skb, len);
1324
1325 memset(padding, 0, padlen);
1326 memcpy(target, data, len);
1327
1328 /* Adjust the chunk length field. */
1329 chunk->chunk_hdr->length = htons(chunklen + padlen + len);
27a884dc 1330 chunk->chunk_end = skb_tail_pointer(chunk->skb);
1da177e4
LT		 1331
1332 return target;
1333}
1334
1335/* Append bytes from user space to the end of a chunk. Will panic if
1336 * chunk is not big enough.
1337 * Returns a kernel err value.
1338 */
1339int sctp_user_addto_chunk(struct sctp_chunk *chunk, int off, int len,
1340 struct iovec *data)
1341{
1342 __u8 *target;
1343 int err = 0;
1344
1345 /* Make room in chunk for data. */
1346 target = skb_put(chunk->skb, len);
1347
1348 /* Copy data (whole iovec) into chunk */
1349 if ((err = memcpy_fromiovecend(target, data, off, len)))
1350 goto out;
1351
1352 /* Adjust the chunk length field. */
1353 chunk->chunk_hdr->length =
1354 htons(ntohs(chunk->chunk_hdr->length) + len);
27a884dc 1355 chunk->chunk_end = skb_tail_pointer(chunk->skb);
1da177e4
LT		 1356
1357out:
1358 return err;
1359}
1360
1361/* Helper function to assign a TSN if needed. This assumes that both
1362 * the data_hdr and association have already been assigned.
1363 */
1364void sctp_chunk_assign_ssn(struct sctp_chunk *chunk)
1365{
ab3e5e7b
VY		 1366 struct sctp_datamsg *msg;
1367 struct sctp_chunk *lchunk;
1368 struct sctp_stream *stream;
1da177e4
LT		 1369 __u16 ssn;
1370 __u16 sid;
1371
1372 if (chunk->has_ssn)
1373 return;
1374
ab3e5e7b
VY		 1375 /* All fragments will be on the same stream */
1376 sid = ntohs(chunk->subh.data_hdr->stream);
1377 stream = &chunk->asoc->ssnmap->out;
1da177e4 1378
ab3e5e7b
VY		 1379 /* Now assign the sequence number to the entire message.
1380 * All fragments must have the same stream sequence number.
1381 */
1382 msg = chunk->msg;
1383 list_for_each_entry(lchunk, &msg->chunks, frag_list) {
1384 if (lchunk->chunk_hdr->flags & SCTP_DATA_UNORDERED) {
1385 ssn = 0;
1386 } else {
1387 if (lchunk->chunk_hdr->flags & SCTP_DATA_LAST_FRAG)
1388 ssn = sctp_ssn_next(stream, sid);
1389 else
1390 ssn = sctp_ssn_peek(stream, sid);
1391 }
1392
1393 lchunk->subh.data_hdr->ssn = htons(ssn);
1394 lchunk->has_ssn = 1;
1395 }
1da177e4
LT		 1396}
1397
1398/* Helper function to assign a TSN if needed. This assumes that both
1399 * the data_hdr and association have already been assigned.
1400 */
1401void sctp_chunk_assign_tsn(struct sctp_chunk *chunk)
1402{
1403 if (!chunk->has_tsn) {
1404 /* This is the last possible instant to
1405 * assign a TSN.
1406 */
1407 chunk->subh.data_hdr->tsn =
1408 htonl(sctp_association_get_next_tsn(chunk->asoc));
1409 chunk->has_tsn = 1;
1410 }
1411}
1412
1413/* Create a CLOSED association to use with an incoming packet. */
1414struct sctp_association *sctp_make_temp_asoc(const struct sctp_endpoint *ep,
3182cd84 1415 struct sctp_chunk *chunk,
dd0fc66f 1416 gfp_t gfp)
1da177e4
LT		 1417{
1418 struct sctp_association *asoc;
1419 struct sk_buff *skb;
1420 sctp_scope_t scope;
1421 struct sctp_af *af;
1422
1423 /* Create the bare association. */
1424 scope = sctp_scope(sctp_source(chunk));
1425 asoc = sctp_association_new(ep, ep->base.sk, scope, gfp);
1426 if (!asoc)
1427 goto nodata;
1428 asoc->temp = 1;
1429 skb = chunk->skb;
1430 /* Create an entry for the source address of the packet. */
eddc9ec5 1431 af = sctp_get_af_specific(ipver2af(ip_hdr(skb)->version));
1da177e4
LT		 1432 if (unlikely(!af))
1433 goto fail;
d55c41b1 1434 af->from_skb(&asoc->c.peer_addr, skb, 1);
1da177e4
LT		 1435nodata:
1436 return asoc;
1437
1438fail:
1439 sctp_association_free(asoc);
1440 return NULL;
1441}
1442
1443/* Build a cookie representing asoc.
1444 * This INCLUDES the param header needed to put the cookie in the INIT ACK.
1445 */
1446static sctp_cookie_param_t *sctp_pack_cookie(const struct sctp_endpoint *ep,
1447 const struct sctp_association *asoc,
1448 const struct sctp_chunk *init_chunk,
1449 int *cookie_len,
1450 const __u8 *raw_addrs, int addrs_len)
1451{
1452 sctp_cookie_param_t *retval;
1453 struct sctp_signed_cookie *cookie;
1454 struct scatterlist sg;
1455 int headersize, bodysize;
1456 unsigned int keylen;
1457 char *key;
1458
9834a2bb
VY		 1459 /* Header size is static data prior to the actual cookie, including
1460 * any padding.
1461 */
d808ad9a
YH		 1462 headersize = sizeof(sctp_paramhdr_t) +
1463 (sizeof(struct sctp_signed_cookie) -
9834a2bb 1464 sizeof(struct sctp_cookie));
1da177e4
LT		 1465 bodysize = sizeof(struct sctp_cookie)
1466 + ntohs(init_chunk->chunk_hdr->length) + addrs_len;
1467
1468 /* Pad out the cookie to a multiple to make the signature
1469 * functions simpler to write.
1470 */
1471 if (bodysize % SCTP_COOKIE_MULTIPLE)
1472 bodysize += SCTP_COOKIE_MULTIPLE
1473 - (bodysize % SCTP_COOKIE_MULTIPLE);
1474 *cookie_len = headersize + bodysize;
1475
1da177e4
LT		 1476 /* Clear this memory since we are sending this data structure
1477 * out on the network.
1478 */
af997d8c
ACM		 1479 retval = kzalloc(*cookie_len, GFP_ATOMIC);
1480 if (!retval)
1481 goto nodata;
1482
1da177e4
LT		 1483 cookie = (struct sctp_signed_cookie *) retval->body;
1484
1485 /* Set up the parameter header. */
1486 retval->p.type = SCTP_PARAM_STATE_COOKIE;
1487 retval->p.length = htons(*cookie_len);
1488
1489 /* Copy the cookie part of the association itself. */
1490 cookie->c = asoc->c;
1491 /* Save the raw address list length in the cookie. */
1492 cookie->c.raw_addr_list_len = addrs_len;
1493
1494 /* Remember PR-SCTP capability. */
1495 cookie->c.prsctp_capable = asoc->peer.prsctp_capable;
1496
0f3fffd8
ISJ		 1497 /* Save adaptation indication in the cookie. */
1498 cookie->c.adaptation_ind = asoc->peer.adaptation_ind;
1da177e4
LT		 1499
1500 /* Set an expiration time for the cookie. */
1501 do_gettimeofday(&cookie->c.expiration);
1502 TIMEVAL_ADD(asoc->cookie_life, cookie->c.expiration);
1503
1504 /* Copy the peer's init packet. */
1505 memcpy(&cookie->c.peer_init[0], init_chunk->chunk_hdr,
1506 ntohs(init_chunk->chunk_hdr->length));
1507
1508 /* Copy the raw local address list of the association. */
1509 memcpy((__u8 *)&cookie->c.peer_init[0] +
1510 ntohs(init_chunk->chunk_hdr->length), raw_addrs, addrs_len);
1511
d808ad9a 1512 if (sctp_sk(ep->base.sk)->hmac) {
1b489e11
HX		 1513 struct hash_desc desc;
1514
1da177e4 1515 /* Sign the message. */
fa05f128
JA		 1516 sg_init_table(&sg, 1);
1517 sg_set_page(&sg, virt_to_page(&cookie->c));
1da177e4
LT		 1518 sg.offset = (unsigned long)(&cookie->c) % PAGE_SIZE;
1519 sg.length = bodysize;
1520 keylen = SCTP_SECRET_SIZE;
1521 key = (char *)ep->secret_key[ep->current_key];
d808ad9a
YH		 1522 desc.tfm = sctp_sk(ep->base.sk)->hmac;
1523 desc.flags = 0;
1da177e4 1524
1b489e11
HX		 1525 if (crypto_hash_setkey(desc.tfm, key, keylen) ||
1526 crypto_hash_digest(&desc, &sg, bodysize, cookie->signature))
1527 goto free_cookie;
1da177e4
LT		 1528 }
1529
1da177e4 1530 return retval;
1b489e11
HX		 1531
1532free_cookie:
1533 kfree(retval);
1534nodata:
1535 *cookie_len = 0;
1536 return NULL;
1da177e4
LT		 1537}
1538
1539/* Unpack the cookie from COOKIE ECHO chunk, recreating the association. */
1540struct sctp_association *sctp_unpack_cookie(
1541 const struct sctp_endpoint *ep,
1542 const struct sctp_association *asoc,
dd0fc66f 1543 struct sctp_chunk *chunk, gfp_t gfp,
1da177e4
LT		 1544 int *error, struct sctp_chunk **errp)
1545{
1546 struct sctp_association *retval = NULL;
1547 struct sctp_signed_cookie *cookie;
1548 struct sctp_cookie *bear_cookie;
1549 int headersize, bodysize, fixed_size;
313e7b4d 1550 __u8 *digest = ep->digest;
1da177e4
LT		 1551 struct scatterlist sg;
1552 unsigned int keylen, len;
1553 char *key;
1554 sctp_scope_t scope;
1555 struct sk_buff *skb = chunk->skb;
a61bbcf2 1556 struct timeval tv;
1b489e11 1557 struct hash_desc desc;
1da177e4 1558
9834a2bb
VY		 1559 /* Header size is static data prior to the actual cookie, including
1560 * any padding.
1561 */
1562 headersize = sizeof(sctp_chunkhdr_t) +
d808ad9a 1563 (sizeof(struct sctp_signed_cookie) -
9834a2bb 1564 sizeof(struct sctp_cookie));
1da177e4
LT		 1565 bodysize = ntohs(chunk->chunk_hdr->length) - headersize;
1566 fixed_size = headersize + sizeof(struct sctp_cookie);
1567
1568 /* Verify that the chunk looks like it even has a cookie.
1569 * There must be enough room for our cookie and our peer's
1570 * INIT chunk.
1571 */
1572 len = ntohs(chunk->chunk_hdr->length);
1573 if (len < fixed_size + sizeof(struct sctp_chunkhdr))
1574 goto malformed;
1575
1576 /* Verify that the cookie has been padded out. */
1577 if (bodysize % SCTP_COOKIE_MULTIPLE)
1578 goto malformed;
1579
1580 /* Process the cookie. */
1581 cookie = chunk->subh.cookie_hdr;
1582 bear_cookie = &cookie->c;
1583
1584 if (!sctp_sk(ep->base.sk)->hmac)
1585 goto no_hmac;
1586
1587 /* Check the signature. */
1588 keylen = SCTP_SECRET_SIZE;
fa05f128
JA		 1589 sg_init_table(&sg, 1);
1590 sg_set_page(&sg, virt_to_page(bear_cookie));
1da177e4
LT		 1591 sg.offset = (unsigned long)(bear_cookie) % PAGE_SIZE;
1592 sg.length = bodysize;
1593 key = (char *)ep->secret_key[ep->current_key];
1b489e11
HX		 1594 desc.tfm = sctp_sk(ep->base.sk)->hmac;
1595 desc.flags = 0;
1da177e4 1596
8ca84481 1597 memset(digest, 0x00, SCTP_SIGNATURE_SIZE);
1b489e11
HX		 1598 if (crypto_hash_setkey(desc.tfm, key, keylen) ||
1599 crypto_hash_digest(&desc, &sg, bodysize, digest)) {
1600 *error = -SCTP_IERROR_NOMEM;
1601 goto fail;
1602 }
1da177e4
LT		 1603
1604 if (memcmp(digest, cookie->signature, SCTP_SIGNATURE_SIZE)) {
1605 /* Try the previous key. */
1606 key = (char *)ep->secret_key[ep->last_key];
8ca84481 1607 memset(digest, 0x00, SCTP_SIGNATURE_SIZE);
1b489e11
HX		 1608 if (crypto_hash_setkey(desc.tfm, key, keylen) ||
1609 crypto_hash_digest(&desc, &sg, bodysize, digest)) {
1610 *error = -SCTP_IERROR_NOMEM;
1611 goto fail;
1612 }
1da177e4
LT		 1613
1614 if (memcmp(digest, cookie->signature, SCTP_SIGNATURE_SIZE)) {
1615 /* Yikes! Still bad signature! */
1616 *error = -SCTP_IERROR_BAD_SIG;
1617 goto fail;
1618 }
1619 }
1620
1621no_hmac:
1622 /* IG Section 2.35.2:
1623 * 3) Compare the port numbers and the verification tag contained
1624 * within the COOKIE ECHO chunk to the actual port numbers and the
1625 * verification tag within the SCTP common header of the received
1626 * packet. If these values do not match the packet MUST be silently
1627 * discarded,
1628 */
1629 if (ntohl(chunk->sctp_hdr->vtag) != bear_cookie->my_vtag) {
1630 *error = -SCTP_IERROR_BAD_TAG;
1631 goto fail;
1632 }
1633
9b1dfad0 1634 if (chunk->sctp_hdr->source != bear_cookie->peer_addr.v4.sin_port ||
1da177e4
LT		 1635 ntohs(chunk->sctp_hdr->dest) != bear_cookie->my_port) {
1636 *error = -SCTP_IERROR_BAD_PORTS;
1637 goto fail;
1638 }
1639
1640 /* Check to see if the cookie is stale. If there is already
1641 * an association, there is no need to check cookie's expiration
1642 * for init collision case of lost COOKIE ACK.
f236218b
VY		 1643 * If skb has been timestamped, then use the stamp, otherwise
1644 * use current time. This introduces a small possibility that
1645 * that a cookie may be considered expired, but his would only slow
1646 * down the new association establishment instead of every packet.
1da177e4 1647 */
f236218b
VY		 1648 if (sock_flag(ep->base.sk, SOCK_TIMESTAMP))
1649 skb_get_timestamp(skb, &tv);
1650 else
1651 do_gettimeofday(&tv);
1652
a61bbcf2 1653 if (!asoc && tv_lt(bear_cookie->expiration, tv)) {
1da177e4
LT		 1654 /*
1655 * Section 3.3.10.3 Stale Cookie Error (3)
1656 *
1657 * Cause of error
1658 * ---------------
1659 * Stale Cookie Error: Indicates the receipt of a valid State
1660 * Cookie that has expired.
1661 */
1662 len = ntohs(chunk->chunk_hdr->length);
1663 *errp = sctp_make_op_error_space(asoc, chunk, len);
1664 if (*errp) {
a61bbcf2 1665 suseconds_t usecs = (tv.tv_sec -
1da177e4 1666 bear_cookie->expiration.tv_sec) * 1000000L +
a61bbcf2 1667 tv.tv_usec - bear_cookie->expiration.tv_usec;
34bcca28 1668 __be32 n = htonl(usecs);
1da177e4 1669
1da177e4 1670 sctp_init_cause(*errp, SCTP_ERROR_STALE_COOKIE,
00f1c2df
WY		 1671 sizeof(n));
1672 sctp_addto_chunk(*errp, sizeof(n), &n);
1da177e4
LT		 1673 *error = -SCTP_IERROR_STALE_COOKIE;
1674 } else
1675 *error = -SCTP_IERROR_NOMEM;
1676
1677 goto fail;
1678 }
1679
1680 /* Make a new base association. */
1681 scope = sctp_scope(sctp_source(chunk));
1682 retval = sctp_association_new(ep, ep->base.sk, scope, gfp);
1683 if (!retval) {
1684 *error = -SCTP_IERROR_NOMEM;
1685 goto fail;
1686 }
1687
1688 /* Set up our peer's port number. */
1689 retval->peer.port = ntohs(chunk->sctp_hdr->source);
1690
1691 /* Populate the association from the cookie. */
1692 memcpy(&retval->c, bear_cookie, sizeof(*bear_cookie));
1693
1694 if (sctp_assoc_set_bind_addr_from_cookie(retval, bear_cookie,
1695 GFP_ATOMIC) < 0) {
1696 *error = -SCTP_IERROR_NOMEM;
1697 goto fail;
1698 }
1699
1700 /* Also, add the destination address. */
1701 if (list_empty(&retval->base.bind_addr.address_list)) {
16b0a030 1702 sctp_add_bind_addr(&retval->base.bind_addr, &chunk->dest, 1,
559cf710 1703 GFP_ATOMIC);
1da177e4
LT		 1704 }
1705
1706 retval->next_tsn = retval->c.initial_tsn;
1707 retval->ctsn_ack_point = retval->next_tsn - 1;
1708 retval->addip_serial = retval->c.initial_tsn;
1709 retval->adv_peer_ack_point = retval->ctsn_ack_point;
1710 retval->peer.prsctp_capable = retval->c.prsctp_capable;
0f3fffd8 1711 retval->peer.adaptation_ind = retval->c.adaptation_ind;
1da177e4
LT		 1712
1713 /* The INIT stuff will be done by the side effects. */
1714 return retval;
1715
1716fail:
1717 if (retval)
1718 sctp_association_free(retval);
1719
1720 return NULL;
1721
1722malformed:
1723 /* Yikes! The packet is either corrupt or deliberately
1724 * malformed.
1725 */
1726 *error = -SCTP_IERROR_MALFORMED;
1727 goto fail;
1728}
1729
1730/********************************************************************
1731 * 3rd Level Abstractions
1732 ********************************************************************/
1733
1734struct __sctp_missing {
9f81bcd9
AV		 1735 __be32 num_missing;
1736 __be16 type;
1da177e4
LT		 1737} __attribute__((packed));
1738
1739/*
1740 * Report a missing mandatory parameter.
1741 */
1742static int sctp_process_missing_param(const struct sctp_association *asoc,
1743 sctp_param_t paramtype,
1744 struct sctp_chunk *chunk,
1745 struct sctp_chunk **errp)
1746{
1747 struct __sctp_missing report;
1748 __u16 len;
1749
1750 len = WORD_ROUND(sizeof(report));
1751
1752 /* Make an ERROR chunk, preparing enough room for
1753 * returning multiple unknown parameters.
1754 */
1755 if (!*errp)
1756 *errp = sctp_make_op_error_space(asoc, chunk, len);
1757
1758 if (*errp) {
1759 report.num_missing = htonl(1);
1760 report.type = paramtype;
ebdfcad4 1761 sctp_init_cause(*errp, SCTP_ERROR_MISS_PARAM,
00f1c2df
WY		 1762 sizeof(report));
1763 sctp_addto_chunk(*errp, sizeof(report), &report);
1da177e4
LT		 1764 }
1765
1766 /* Stop processing this chunk. */
1767 return 0;
1768}
1769
1770/* Report an Invalid Mandatory Parameter. */
1771static int sctp_process_inv_mandatory(const struct sctp_association *asoc,
1772 struct sctp_chunk *chunk,
1773 struct sctp_chunk **errp)
1774{
1775 /* Invalid Mandatory Parameter Error has no payload. */
1776
1777 if (!*errp)
1778 *errp = sctp_make_op_error_space(asoc, chunk, 0);
1779
1780 if (*errp)
00f1c2df 1781 sctp_init_cause(*errp, SCTP_ERROR_INV_PARAM, 0);
1da177e4
LT		 1782
1783 /* Stop processing this chunk. */
1784 return 0;
1785}
1786
1787static int sctp_process_inv_paramlength(const struct sctp_association *asoc,
1788 struct sctp_paramhdr *param,
1789 const struct sctp_chunk *chunk,
1790 struct sctp_chunk **errp)
1791{
1792 char error[] = "The following parameter had invalid length:";
d808ad9a 1793 size_t payload_len = WORD_ROUND(sizeof(error)) +
1da177e4
LT		 1794 sizeof(sctp_paramhdr_t);
1795
1796
1797 /* Create an error chunk and fill it in with our payload. */
1798 if (!*errp)
1799 *errp = sctp_make_op_error_space(asoc, chunk, payload_len);
1800
1801 if (*errp) {
00f1c2df
WY		 1802 sctp_init_cause(*errp, SCTP_ERROR_PROTO_VIOLATION,
1803 sizeof(error) + sizeof(sctp_paramhdr_t));
1804 sctp_addto_chunk(*errp, sizeof(error), error);
1805 sctp_addto_param(*errp, sizeof(sctp_paramhdr_t), param);
1da177e4
LT		 1806 }
1807
1808 return 0;
1809}
1810
1811
1812/* Do not attempt to handle the HOST_NAME parm. However, do
1813 * send back an indicator to the peer.
1814 */
1815static int sctp_process_hn_param(const struct sctp_association *asoc,
1816 union sctp_params param,
1817 struct sctp_chunk *chunk,
1818 struct sctp_chunk **errp)
1819{
1820 __u16 len = ntohs(param.p->length);
1821
1822 /* Make an ERROR chunk. */
1823 if (!*errp)
1824 *errp = sctp_make_op_error_space(asoc, chunk, len);
1825
00f1c2df
WY		 1826 if (*errp) {
1827 sctp_init_cause(*errp, SCTP_ERROR_DNS_FAILED, len);
1828 sctp_addto_chunk(*errp, len, param.v);
1829 }
1da177e4
LT		 1830
1831 /* Stop processing this chunk. */
1832 return 0;
1833}
1834
131a47e3
VY		 1835static void sctp_process_ext_param(struct sctp_association *asoc,
1836 union sctp_params param)
1837{
1838 __u16 num_ext = ntohs(param.p->length) - sizeof(sctp_paramhdr_t);
1839 int i;
1840
1841 for (i = 0; i < num_ext; i++) {
1842 switch (param.ext->chunks[i]) {
1843 case SCTP_CID_FWD_TSN:
1844 if (sctp_prsctp_enable &&
1845 !asoc->peer.prsctp_capable)
1846 asoc->peer.prsctp_capable = 1;
1847 break;
730fc3d0
VY		 1848 case SCTP_CID_AUTH:
1849 /* if the peer reports AUTH, assume that he
1850 * supports AUTH.
1851 */
1852 asoc->peer.auth_capable = 1;
1853 break;
131a47e3
VY		 1854 case SCTP_CID_ASCONF:
1855 case SCTP_CID_ASCONF_ACK:
6b2f9cb6
VY		 1856 asoc->peer.addip_capable = 1;
1857 break;
131a47e3
VY		 1858 default:
1859 break;
1860 }
1861 }
1862}
1863
1da177e4
LT		 1864/* RFC 3.2.1 & the Implementers Guide 2.2.
1865 *
1866 * The Parameter Types are encoded such that the
1867 * highest-order two bits specify the action that must be
1868 * taken if the processing endpoint does not recognize the
1869 * Parameter Type.
1870 *
1871 * 00 - Stop processing this SCTP chunk and discard it,
1872 * do not process any further chunks within it.
1873 *
1874 * 01 - Stop processing this SCTP chunk and discard it,
1875 * do not process any further chunks within it, and report
1876 * the unrecognized parameter in an 'Unrecognized
1877 * Parameter Type' (in either an ERROR or in the INIT ACK).
1878 *
1879 * 10 - Skip this parameter and continue processing.
1880 *
1881 * 11 - Skip this parameter and continue processing but
1882 * report the unrecognized parameter in an
1883 * 'Unrecognized Parameter Type' (in either an ERROR or in
1884 * the INIT ACK).
1885 *
1886 * Return value:
1887 * 0 - discard the chunk
1888 * 1 - continue with the chunk
1889 */
1890static int sctp_process_unk_param(const struct sctp_association *asoc,
1891 union sctp_params param,
1892 struct sctp_chunk *chunk,
1893 struct sctp_chunk **errp)
1894{
1895 int retval = 1;
1896
1897 switch (param.p->type & SCTP_PARAM_ACTION_MASK) {
1898 case SCTP_PARAM_ACTION_DISCARD:
1899 retval = 0;
1900 break;
1901 case SCTP_PARAM_ACTION_DISCARD_ERR:
1902 retval = 0;
1903 /* Make an ERROR chunk, preparing enough room for
1904 * returning multiple unknown parameters.
1905 */
1906 if (NULL == *errp)
1907 *errp = sctp_make_op_error_space(asoc, chunk,
1908 ntohs(chunk->chunk_hdr->length));
1909
00f1c2df 1910 if (*errp) {
1da177e4 1911 sctp_init_cause(*errp, SCTP_ERROR_UNKNOWN_PARAM,
1da177e4 1912 WORD_ROUND(ntohs(param.p->length)));
00f1c2df
WY		 1913 sctp_addto_chunk(*errp,
1914 WORD_ROUND(ntohs(param.p->length)),
1915 param.v);
1916 }
1da177e4
LT		 1917
1918 break;
1919 case SCTP_PARAM_ACTION_SKIP:
1920 break;
1921 case SCTP_PARAM_ACTION_SKIP_ERR:
1922 /* Make an ERROR chunk, preparing enough room for
1923 * returning multiple unknown parameters.
1924 */
1925 if (NULL == *errp)
1926 *errp = sctp_make_op_error_space(asoc, chunk,
1927 ntohs(chunk->chunk_hdr->length));
1928
1929 if (*errp) {
1930 sctp_init_cause(*errp, SCTP_ERROR_UNKNOWN_PARAM,
1da177e4 1931 WORD_ROUND(ntohs(param.p->length)));
00f1c2df
WY		 1932 sctp_addto_chunk(*errp,
1933 WORD_ROUND(ntohs(param.p->length)),
1934 param.v);
1da177e4
LT		 1935 } else {
1936 /* If there is no memory for generating the ERROR
1937 * report as specified, an ABORT will be triggered
1938 * to the peer and the association won't be
1939 * established.
1940 */
1941 retval = 0;
1942 }
1943
1944 break;
1945 default:
1946 break;
1947 }
1948
1949 return retval;
1950}
1951
1952/* Find unrecognized parameters in the chunk.
1953 * Return values:
1954 * 0 - discard the chunk
1955 * 1 - continue with the chunk
1956 */
1957static int sctp_verify_param(const struct sctp_association *asoc,
1958 union sctp_params param,
1959 sctp_cid_t cid,
1960 struct sctp_chunk *chunk,
1961 struct sctp_chunk **err_chunk)
1962{
1963 int retval = 1;
1964
1965 /* FIXME - This routine is not looking at each parameter per the
1966 * chunk type, i.e., unrecognized parameters should be further
1967 * identified based on the chunk id.
1968 */
1969
1970 switch (param.p->type) {
1971 case SCTP_PARAM_IPV4_ADDRESS:
1972 case SCTP_PARAM_IPV6_ADDRESS:
1973 case SCTP_PARAM_COOKIE_PRESERVATIVE:
1974 case SCTP_PARAM_SUPPORTED_ADDRESS_TYPES:
1975 case SCTP_PARAM_STATE_COOKIE:
1976 case SCTP_PARAM_HEARTBEAT_INFO:
1977 case SCTP_PARAM_UNRECOGNIZED_PARAMETERS:
1978 case SCTP_PARAM_ECN_CAPABLE:
0f3fffd8 1979 case SCTP_PARAM_ADAPTATION_LAYER_IND:
131a47e3 1980 case SCTP_PARAM_SUPPORTED_EXT:
1da177e4
LT		 1981 break;
1982
1983 case SCTP_PARAM_HOST_NAME_ADDRESS:
1984 /* Tell the peer, we won't support this param. */
1985 return sctp_process_hn_param(asoc, param, chunk, err_chunk);
131a47e3 1986
1da177e4
LT		 1987 case SCTP_PARAM_FWD_TSN_SUPPORT:
1988 if (sctp_prsctp_enable)
1989 break;
730fc3d0
VY		 1990 goto fallthrough;
1991
1992 case SCTP_PARAM_RANDOM:
1993 if (!sctp_auth_enable)
1994 goto fallthrough;
1995
1996 /* SCTP-AUTH: Secion 6.1
1997 * If the random number is not 32 byte long the association
1998 * MUST be aborted. The ABORT chunk SHOULD contain the error
1999 * cause 'Protocol Violation'.
2000 */
2001 if (SCTP_AUTH_RANDOM_LENGTH !=
2002 ntohs(param.p->length) - sizeof(sctp_paramhdr_t))
2003 return sctp_process_inv_paramlength(asoc, param.p,
2004 chunk, err_chunk);
2005 break;
2006
2007 case SCTP_PARAM_CHUNKS:
2008 if (!sctp_auth_enable)
2009 goto fallthrough;
2010
2011 /* SCTP-AUTH: Section 3.2
2012 * The CHUNKS parameter MUST be included once in the INIT or
2013 * INIT-ACK chunk if the sender wants to receive authenticated
2014 * chunks. Its maximum length is 260 bytes.
2015 */
2016 if (260 < ntohs(param.p->length))
2017 return sctp_process_inv_paramlength(asoc, param.p,
2018 chunk, err_chunk);
2019 break;
2020
2021 case SCTP_PARAM_HMAC_ALGO:
2022 if (!sctp_auth_enable)
2023 break;
d808ad9a 2024 /* Fall Through */
730fc3d0 2025fallthrough:
1da177e4
LT		 2026 default:
2027 SCTP_DEBUG_PRINTK("Unrecognized param: %d for chunk %d.\n",
2028 ntohs(param.p->type), cid);
2029 return sctp_process_unk_param(asoc, param, chunk, err_chunk);
2030
2031 break;
2032 }
2033 return retval;
2034}
2035
2036/* Verify the INIT packet before we process it. */
2037int sctp_verify_init(const struct sctp_association *asoc,
2038 sctp_cid_t cid,
2039 sctp_init_chunk_t *peer_init,
2040 struct sctp_chunk *chunk,
2041 struct sctp_chunk **errp)
2042{
2043 union sctp_params param;
2044 int has_cookie = 0;
2045
2046 /* Verify stream values are non-zero. */
2047 if ((0 == peer_init->init_hdr.num_outbound_streams) ||
d023f629
VY		 2048 (0 == peer_init->init_hdr.num_inbound_streams) ||
2049 (0 == peer_init->init_hdr.init_tag) ||
2050 (SCTP_DEFAULT_MINWINDOW > ntohl(peer_init->init_hdr.a_rwnd))) {
1da177e4
LT		 2051
2052 sctp_process_inv_mandatory(asoc, chunk, errp);
2053 return 0;
2054 }
2055
2056 /* Check for missing mandatory parameters. */
2057 sctp_walk_params(param, peer_init, init_hdr.params) {
2058
2059 if (SCTP_PARAM_STATE_COOKIE == param.p->type)
2060 has_cookie = 1;
2061
2062 } /* for (loop through all parameters) */
2063
2064 /* There is a possibility that a parameter length was bad and
2065 * in that case we would have stoped walking the parameters.
2066 * The current param.p would point at the bad one.
2067 * Current consensus on the mailing list is to generate a PROTOCOL
2068 * VIOLATION error. We build the ERROR chunk here and let the normal
2069 * error handling code build and send the packet.
2070 */
cb243a1a 2071 if (param.v != (void*)chunk->chunk_end) {
1da177e4
LT		 2072 sctp_process_inv_paramlength(asoc, param.p, chunk, errp);
2073 return 0;
2074 }
2075
2076 /* The only missing mandatory param possible today is
2077 * the state cookie for an INIT-ACK chunk.
2078 */
2079 if ((SCTP_CID_INIT_ACK == cid) && !has_cookie) {
2080 sctp_process_missing_param(asoc, SCTP_PARAM_STATE_COOKIE,
2081 chunk, errp);
2082 return 0;
2083 }
2084
2085 /* Find unrecognized parameters. */
2086
2087 sctp_walk_params(param, peer_init, init_hdr.params) {
2088
2089 if (!sctp_verify_param(asoc, param, cid, chunk, errp)) {
2090 if (SCTP_PARAM_HOST_NAME_ADDRESS == param.p->type)
2091 return 0;
2092 else
2093 return 1;
2094 }
2095
2096 } /* for (loop through all parameters) */
2097
2098 return 1;
2099}
2100
2101/* Unpack the parameters in an INIT packet into an association.
2102 * Returns 0 on failure, else success.
2103 * FIXME: This is an association method.
2104 */
2105int sctp_process_init(struct sctp_association *asoc, sctp_cid_t cid,
2106 const union sctp_addr *peer_addr,
dd0fc66f 2107 sctp_init_chunk_t *peer_init, gfp_t gfp)
1da177e4
LT		 2108{
2109 union sctp_params param;
2110 struct sctp_transport *transport;
2111 struct list_head *pos, *temp;
2112 char *cookie;
2113
2114 /* We must include the address that the INIT packet came from.
2115 * This is the only address that matters for an INIT packet.
2116 * When processing a COOKIE ECHO, we retrieve the from address
2117 * of the INIT from the cookie.
2118 */
2119
2120 /* This implementation defaults to making the first transport
2121 * added as the primary transport. The source address seems to
2122 * be a a better choice than any of the embedded addresses.
2123 */
4bdf4b5f 2124 if (peer_addr) {
6a1e5f33 2125 if(!sctp_assoc_add_peer(asoc, peer_addr, gfp, SCTP_ACTIVE))
1da177e4 2126 goto nomem;
4bdf4b5f 2127 }
1da177e4
LT		 2128
2129 /* Process the initialization parameters. */
1da177e4
LT		 2130 sctp_walk_params(param, peer_init, init_hdr.params) {
2131
2132 if (!sctp_process_param(asoc, param, peer_addr, gfp))
d808ad9a 2133 goto clean_up;
1da177e4
LT		 2134 }
2135
730fc3d0
VY		 2136 /* AUTH: After processing the parameters, make sure that we
2137 * have all the required info to potentially do authentications.
2138 */
2139 if (asoc->peer.auth_capable && (!asoc->peer.peer_random ||
2140 !asoc->peer.peer_hmacs))
2141 asoc->peer.auth_capable = 0;
2142
6b2f9cb6
VY		 2143
2144 /* If the peer claims support for ADD-IP without support
2145 * for AUTH, disable support for ADD-IP.
2146 */
2147 if (asoc->peer.addip_capable && !asoc->peer.auth_capable) {
2148 asoc->peer.addip_disabled_mask |= (SCTP_PARAM_ADD_IP |
2149 SCTP_PARAM_DEL_IP |
2150 SCTP_PARAM_SET_PRIMARY);
2151 }
2152
3f7a87d2
FF		 2153 /* Walk list of transports, removing transports in the UNKNOWN state. */
2154 list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
2155 transport = list_entry(pos, struct sctp_transport, transports);
2156 if (transport->state == SCTP_UNKNOWN) {
2157 sctp_assoc_rm_peer(asoc, transport);
2158 }
2159 }
2160
1da177e4
LT		 2161 /* The fixed INIT headers are always in network byte
2162 * order.
2163 */
2164 asoc->peer.i.init_tag =
2165 ntohl(peer_init->init_hdr.init_tag);
2166 asoc->peer.i.a_rwnd =
2167 ntohl(peer_init->init_hdr.a_rwnd);
2168 asoc->peer.i.num_outbound_streams =
2169 ntohs(peer_init->init_hdr.num_outbound_streams);
2170 asoc->peer.i.num_inbound_streams =
2171 ntohs(peer_init->init_hdr.num_inbound_streams);
2172 asoc->peer.i.initial_tsn =
2173 ntohl(peer_init->init_hdr.initial_tsn);
2174
2175 /* Apply the upper bounds for output streams based on peer's
2176 * number of inbound streams.
2177 */
2178 if (asoc->c.sinit_num_ostreams >
2179 ntohs(peer_init->init_hdr.num_inbound_streams)) {
2180 asoc->c.sinit_num_ostreams =
2181 ntohs(peer_init->init_hdr.num_inbound_streams);
2182 }
2183
2184 if (asoc->c.sinit_max_instreams >
2185 ntohs(peer_init->init_hdr.num_outbound_streams)) {
2186 asoc->c.sinit_max_instreams =
2187 ntohs(peer_init->init_hdr.num_outbound_streams);
2188 }
2189
2190 /* Copy Initiation tag from INIT to VT_peer in cookie. */
2191 asoc->c.peer_vtag = asoc->peer.i.init_tag;
2192
2193 /* Peer Rwnd : Current calculated value of the peer's rwnd. */
2194 asoc->peer.rwnd = asoc->peer.i.a_rwnd;
2195
2196 /* Copy cookie in case we need to resend COOKIE-ECHO. */
2197 cookie = asoc->peer.cookie;
2198 if (cookie) {
af997d8c 2199 asoc->peer.cookie = kmemdup(cookie, asoc->peer.cookie_len, gfp);
1da177e4
LT		 2200 if (!asoc->peer.cookie)
2201 goto clean_up;
1da177e4
LT		 2202 }
2203
2204 /* RFC 2960 7.2.1 The initial value of ssthresh MAY be arbitrarily
2205 * high (for example, implementations MAY use the size of the receiver
2206 * advertised window).
2207 */
2208 list_for_each(pos, &asoc->peer.transport_addr_list) {
2209 transport = list_entry(pos, struct sctp_transport, transports);
2210 transport->ssthresh = asoc->peer.i.a_rwnd;
2211 }
2212
2213 /* Set up the TSN tracking pieces. */
2214 sctp_tsnmap_init(&asoc->peer.tsn_map, SCTP_TSN_MAP_SIZE,
2215 asoc->peer.i.initial_tsn);
2216
2217 /* RFC 2960 6.5 Stream Identifier and Stream Sequence Number
2218 *
2219 * The stream sequence number in all the streams shall start
2220 * from 0 when the association is established. Also, when the
2221 * stream sequence number reaches the value 65535 the next
2222 * stream sequence number shall be set to 0.
2223 */
2224
3f7a87d2 2225 /* Allocate storage for the negotiated streams if it is not a temporary
d808ad9a 2226 * association.
1da177e4
LT		 2227 */
2228 if (!asoc->temp) {
1da177e4
LT		 2229 int error;
2230
2231 asoc->ssnmap = sctp_ssnmap_new(asoc->c.sinit_max_instreams,
2232 asoc->c.sinit_num_ostreams, gfp);
2233 if (!asoc->ssnmap)
2234 goto clean_up;
2235
07d93967
VY		 2236 error = sctp_assoc_set_id(asoc, gfp);
2237 if (error)
1da177e4 2238 goto clean_up;
1da177e4
LT		 2239 }
2240
2241 /* ADDIP Section 4.1 ASCONF Chunk Procedures
2242 *
2243 * When an endpoint has an ASCONF signaled change to be sent to the
2244 * remote endpoint it should do the following:
2245 * ...
2246 * A2) A serial number should be assigned to the Chunk. The serial
2247 * number should be a monotonically increasing number. All serial
2248 * numbers are defined to be initialized at the start of the
2249 * association to the same value as the Initial TSN.
2250 */
2251 asoc->peer.addip_serial = asoc->peer.i.initial_tsn - 1;
2252 return 1;
2253
2254clean_up:
2255 /* Release the transport structures. */
2256 list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
2257 transport = list_entry(pos, struct sctp_transport, transports);
2258 list_del_init(pos);
2259 sctp_transport_free(transport);
2260 }
3f7a87d2
FF		 2261
2262 asoc->peer.transport_count = 0;
2263
1da177e4
LT		 2264nomem:
2265 return 0;
2266}
2267
2268
2269/* Update asoc with the option described in param.
2270 *
2271 * RFC2960 3.3.2.1 Optional/Variable Length Parameters in INIT
2272 *
2273 * asoc is the association to update.
2274 * param is the variable length parameter to use for update.
2275 * cid tells us if this is an INIT, INIT ACK or COOKIE ECHO.
2276 * If the current packet is an INIT we want to minimize the amount of
2277 * work we do. In particular, we should not build transport
2278 * structures for the addresses.
2279 */
2280static int sctp_process_param(struct sctp_association *asoc,
2281 union sctp_params param,
2282 const union sctp_addr *peer_addr,
dd0fc66f 2283 gfp_t gfp)
1da177e4
LT		 2284{
2285 union sctp_addr addr;
2286 int i;
2287 __u16 sat;
2288 int retval = 1;
2289 sctp_scope_t scope;
2290 time_t stale;
2291 struct sctp_af *af;
2292
2293 /* We maintain all INIT parameters in network byte order all the
2294 * time. This allows us to not worry about whether the parameters
2295 * came from a fresh INIT, and INIT ACK, or were stored in a cookie.
2296 */
2297 switch (param.p->type) {
2298 case SCTP_PARAM_IPV6_ADDRESS:
2299 if (PF_INET6 != asoc->base.sk->sk_family)
2300 break;
2301 /* Fall through. */
2302 case SCTP_PARAM_IPV4_ADDRESS:
2303 af = sctp_get_af_specific(param_type2af(param.p->type));
dd86d136 2304 af->from_addr_param(&addr, param.addr, htons(asoc->peer.port), 0);
1da177e4 2305 scope = sctp_scope(peer_addr);
dd86d136
AV		 2306 if (sctp_in_scope(&addr, scope))
2307 if (!sctp_assoc_add_peer(asoc, &addr, gfp, SCTP_UNCONFIRMED))
1da177e4
LT		 2308 return 0;
2309 break;
2310
2311 case SCTP_PARAM_COOKIE_PRESERVATIVE:
2312 if (!sctp_cookie_preserve_enable)
2313 break;
2314
2315 stale = ntohl(param.life->lifespan_increment);
2316
2317 /* Suggested Cookie Life span increment's unit is msec,
2318 * (1/1000sec).
2319 */
2320 asoc->cookie_life.tv_sec += stale / 1000;
2321 asoc->cookie_life.tv_usec += (stale % 1000) * 1000;
2322 break;
2323
2324 case SCTP_PARAM_HOST_NAME_ADDRESS:
2325 SCTP_DEBUG_PRINTK("unimplemented SCTP_HOST_NAME_ADDRESS\n");
2326 break;
2327
2328 case SCTP_PARAM_SUPPORTED_ADDRESS_TYPES:
2329 /* Turn off the default values first so we'll know which
2330 * ones are really set by the peer.
2331 */
2332 asoc->peer.ipv4_address = 0;
2333 asoc->peer.ipv6_address = 0;
2334
2335 /* Cycle through address types; avoid divide by 0. */
2336 sat = ntohs(param.p->length) - sizeof(sctp_paramhdr_t);
2337 if (sat)
2338 sat /= sizeof(__u16);
2339
2340 for (i = 0; i < sat; ++i) {
2341 switch (param.sat->types[i]) {
2342 case SCTP_PARAM_IPV4_ADDRESS:
2343 asoc->peer.ipv4_address = 1;
2344 break;
2345
2346 case SCTP_PARAM_IPV6_ADDRESS:
2347 asoc->peer.ipv6_address = 1;
2348 break;
2349
2350 case SCTP_PARAM_HOST_NAME_ADDRESS:
2351 asoc->peer.hostname_address = 1;
2352 break;
2353
2354 default: /* Just ignore anything else. */
2355 break;
3ff50b79 2356 }
1da177e4
LT		 2357 }
2358 break;
2359
2360 case SCTP_PARAM_STATE_COOKIE:
2361 asoc->peer.cookie_len =
2362 ntohs(param.p->length) - sizeof(sctp_paramhdr_t);
2363 asoc->peer.cookie = param.cookie->body;
2364 break;
2365
2366 case SCTP_PARAM_HEARTBEAT_INFO:
2367 /* Would be odd to receive, but it causes no problems. */
2368 break;
2369
2370 case SCTP_PARAM_UNRECOGNIZED_PARAMETERS:
2371 /* Rejected during verify stage. */
2372 break;
2373
2374 case SCTP_PARAM_ECN_CAPABLE:
2375 asoc->peer.ecn_capable = 1;
2376 break;
2377
0f3fffd8
ISJ		 2378 case SCTP_PARAM_ADAPTATION_LAYER_IND:
2379 asoc->peer.adaptation_ind = param.aind->adaptation_ind;
1da177e4
LT		 2380 break;
2381
131a47e3
VY		 2382 case SCTP_PARAM_SUPPORTED_EXT:
2383 sctp_process_ext_param(asoc, param);
2384 break;
2385
1da177e4
LT		 2386 case SCTP_PARAM_FWD_TSN_SUPPORT:
2387 if (sctp_prsctp_enable) {
2388 asoc->peer.prsctp_capable = 1;
2389 break;
2390 }
d808ad9a 2391 /* Fall Through */
730fc3d0
VY		 2392 goto fall_through;
2393
2394 case SCTP_PARAM_RANDOM:
2395 if (!sctp_auth_enable)
2396 goto fall_through;
2397
2398 /* Save peer's random parameter */
2399 asoc->peer.peer_random = kmemdup(param.p,
2400 ntohs(param.p->length), gfp);
2401 if (!asoc->peer.peer_random) {
2402 retval = 0;
2403 break;
2404 }
2405 break;
2406
2407 case SCTP_PARAM_HMAC_ALGO:
2408 if (!sctp_auth_enable)
2409 goto fall_through;
2410
2411 /* Save peer's HMAC list */
2412 asoc->peer.peer_hmacs = kmemdup(param.p,
2413 ntohs(param.p->length), gfp);
2414 if (!asoc->peer.peer_hmacs) {
2415 retval = 0;
2416 break;
2417 }
2418
2419 /* Set the default HMAC the peer requested*/
2420 sctp_auth_asoc_set_default_hmac(asoc, param.hmac_algo);
2421 break;
2422
2423 case SCTP_PARAM_CHUNKS:
2424 if (!sctp_auth_enable)
2425 goto fall_through;
2426
2427 asoc->peer.peer_chunks = kmemdup(param.p,
2428 ntohs(param.p->length), gfp);
2429 if (!asoc->peer.peer_chunks)
2430 retval = 0;
2431 break;
2432fall_through:
1da177e4
LT		 2433 default:
2434 /* Any unrecognized parameters should have been caught
2435 * and handled by sctp_verify_param() which should be
2436 * called prior to this routine. Simply log the error
2437 * here.
2438 */
2439 SCTP_DEBUG_PRINTK("Ignoring param: %d for association %p.\n",
2440 ntohs(param.p->type), asoc);
2441 break;
3ff50b79 2442 }
1da177e4
LT		 2443
2444 return retval;
2445}
2446
2447/* Select a new verification tag. */
2448__u32 sctp_generate_tag(const struct sctp_endpoint *ep)
2449{
2450 /* I believe that this random number generator complies with RFC1750.
2451 * A tag of 0 is reserved for special cases (e.g. INIT).
2452 */
2453 __u32 x;
2454
2455 do {
2456 get_random_bytes(&x, sizeof(__u32));
2457 } while (x == 0);
2458
2459 return x;
2460}
2461
2462/* Select an initial TSN to send during startup. */
2463__u32 sctp_generate_tsn(const struct sctp_endpoint *ep)
2464{
2465 __u32 retval;
2466
2467 get_random_bytes(&retval, sizeof(__u32));
2468 return retval;
2469}
2470
2471/*
2472 * ADDIP 3.1.1 Address Configuration Change Chunk (ASCONF)
2473 * 0 1 2 3
2474 * 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
2475 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2476 * | Type = 0xC1 | Chunk Flags | Chunk Length |
2477 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2478 * | Serial Number |
2479 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2480 * | Address Parameter |
2481 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2482 * | ASCONF Parameter #1 |
2483 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2484 * \ \
2485 * / .... /
2486 * \ \
2487 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2488 * | ASCONF Parameter #N |
2489 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2490 *
d808ad9a 2491 * Address Parameter and other parameter will not be wrapped in this function
1da177e4
LT		 2492 */
2493static struct sctp_chunk *sctp_make_asconf(struct sctp_association *asoc,
2494 union sctp_addr *addr,
2495 int vparam_len)
2496{
2497 sctp_addiphdr_t asconf;
2498 struct sctp_chunk *retval;
2499 int length = sizeof(asconf) + vparam_len;
2500 union sctp_addr_param addrparam;
2501 int addrlen;
2502 struct sctp_af *af = sctp_get_af_specific(addr->v4.sin_family);
2503
2504 addrlen = af->to_addr_param(addr, &addrparam);
2505 if (!addrlen)
2506 return NULL;
2507 length += addrlen;
2508
2509 /* Create the chunk. */
2510 retval = sctp_make_chunk(asoc, SCTP_CID_ASCONF, 0, length);
2511 if (!retval)
2512 return NULL;
2513
2514 asconf.serial = htonl(asoc->addip_serial++);
2515
2516 retval->subh.addip_hdr =
2517 sctp_addto_chunk(retval, sizeof(asconf), &asconf);
2518 retval->param_hdr.v =
2519 sctp_addto_chunk(retval, addrlen, &addrparam);
2520
2521 return retval;
2522}
2523
2524/* ADDIP
2525 * 3.2.1 Add IP Address
2526 * 0 1 2 3
2527 * 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
2528 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2529 * | Type = 0xC001 | Length = Variable |
2530 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2531 * | ASCONF-Request Correlation ID |
2532 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2533 * | Address Parameter |
2534 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2535 *
2536 * 3.2.2 Delete IP Address
2537 * 0 1 2 3
2538 * 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
2539 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2540 * | Type = 0xC002 | Length = Variable |
2541 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2542 * | ASCONF-Request Correlation ID |
2543 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2544 * | Address Parameter |
2545 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2546 *
2547 */
2548struct sctp_chunk *sctp_make_asconf_update_ip(struct sctp_association *asoc,
2549 union sctp_addr *laddr,
2550 struct sockaddr *addrs,
2551 int addrcnt,
dbc16db1 2552 __be16 flags)
1da177e4
LT		 2553{
2554 sctp_addip_param_t param;
2555 struct sctp_chunk *retval;
2556 union sctp_addr_param addr_param;
2557 union sctp_addr *addr;
2558 void *addr_buf;
2559 struct sctp_af *af;
2560 int paramlen = sizeof(param);
2561 int addr_param_len = 0;
2562 int totallen = 0;
2563 int i;
2564
2565 /* Get total length of all the address parameters. */
2566 addr_buf = addrs;
2567 for (i = 0; i < addrcnt; i++) {
2568 addr = (union sctp_addr *)addr_buf;
2569 af = sctp_get_af_specific(addr->v4.sin_family);
2570 addr_param_len = af->to_addr_param(addr, &addr_param);
2571
2572 totallen += paramlen;
2573 totallen += addr_param_len;
2574
2575 addr_buf += af->sockaddr_len;
2576 }
2577
2578 /* Create an asconf chunk with the required length. */
2579 retval = sctp_make_asconf(asoc, laddr, totallen);
2580 if (!retval)
2581 return NULL;
2582
2583 /* Add the address parameters to the asconf chunk. */
2584 addr_buf = addrs;
2585 for (i = 0; i < addrcnt; i++) {
2586 addr = (union sctp_addr *)addr_buf;
2587 af = sctp_get_af_specific(addr->v4.sin_family);
2588 addr_param_len = af->to_addr_param(addr, &addr_param);
2589 param.param_hdr.type = flags;
2590 param.param_hdr.length = htons(paramlen + addr_param_len);
2591 param.crr_id = i;
2592
2593 sctp_addto_chunk(retval, paramlen, &param);
2594 sctp_addto_chunk(retval, addr_param_len, &addr_param);
2595
2596 addr_buf += af->sockaddr_len;
2597 }
2598 return retval;
2599}
2600
2601/* ADDIP
2602 * 3.2.4 Set Primary IP Address
2603 * 0 1 2 3
2604 * 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
2605 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2606 * | Type =0xC004 | Length = Variable |
2607 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2608 * | ASCONF-Request Correlation ID |
2609 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2610 * | Address Parameter |
2611 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2612 *
d808ad9a 2613 * Create an ASCONF chunk with Set Primary IP address parameter.
1da177e4
LT		 2614 */
2615struct sctp_chunk *sctp_make_asconf_set_prim(struct sctp_association *asoc,
2616 union sctp_addr *addr)
2617{
2618 sctp_addip_param_t param;
2619 struct sctp_chunk *retval;
2620 int len = sizeof(param);
2621 union sctp_addr_param addrparam;
2622 int addrlen;
2623 struct sctp_af *af = sctp_get_af_specific(addr->v4.sin_family);
2624
2625 addrlen = af->to_addr_param(addr, &addrparam);
2626 if (!addrlen)
2627 return NULL;
2628 len += addrlen;
2629
2630 /* Create the chunk and make asconf header. */
2631 retval = sctp_make_asconf(asoc, addr, len);
2632 if (!retval)
2633 return NULL;
2634
2635 param.param_hdr.type = SCTP_PARAM_SET_PRIMARY;
2636 param.param_hdr.length = htons(len);
2637 param.crr_id = 0;
2638
2639 sctp_addto_chunk(retval, sizeof(param), &param);
2640 sctp_addto_chunk(retval, addrlen, &addrparam);
2641
2642 return retval;
2643}
2644
2645/* ADDIP 3.1.2 Address Configuration Acknowledgement Chunk (ASCONF-ACK)
2646 * 0 1 2 3
2647 * 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
2648 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2649 * | Type = 0x80 | Chunk Flags | Chunk Length |
2650 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2651 * | Serial Number |
2652 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2653 * | ASCONF Parameter Response#1 |
2654 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2655 * \ \
2656 * / .... /
2657 * \ \
2658 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2659 * | ASCONF Parameter Response#N |
2660 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2661 *
d808ad9a 2662 * Create an ASCONF_ACK chunk with enough space for the parameter responses.
1da177e4
LT		 2663 */
2664static struct sctp_chunk *sctp_make_asconf_ack(const struct sctp_association *asoc,
2665 __u32 serial, int vparam_len)
2666{
2667 sctp_addiphdr_t asconf;
2668 struct sctp_chunk *retval;
2669 int length = sizeof(asconf) + vparam_len;
2670
2671 /* Create the chunk. */
2672 retval = sctp_make_chunk(asoc, SCTP_CID_ASCONF_ACK, 0, length);
2673 if (!retval)
2674 return NULL;
2675
2676 asconf.serial = htonl(serial);
2677
2678 retval->subh.addip_hdr =
2679 sctp_addto_chunk(retval, sizeof(asconf), &asconf);
2680
2681 return retval;
2682}
2683
2684/* Add response parameters to an ASCONF_ACK chunk. */
9f81bcd9 2685static void sctp_add_asconf_response(struct sctp_chunk *chunk, __be32 crr_id,
dbc16db1 2686 __be16 err_code, sctp_addip_param_t *asconf_param)
1da177e4
LT		 2687{
2688 sctp_addip_param_t ack_param;
2689 sctp_errhdr_t err_param;
2690 int asconf_param_len = 0;
2691 int err_param_len = 0;
dbc16db1 2692 __be16 response_type;
1da177e4
LT		 2693
2694 if (SCTP_ERROR_NO_ERROR == err_code) {
2695 response_type = SCTP_PARAM_SUCCESS_REPORT;
2696 } else {
2697 response_type = SCTP_PARAM_ERR_CAUSE;
2698 err_param_len = sizeof(err_param);
2699 if (asconf_param)
2700 asconf_param_len =
2701 ntohs(asconf_param->param_hdr.length);
2702 }
2703
d808ad9a 2704 /* Add Success Indication or Error Cause Indication parameter. */
1da177e4
LT		 2705 ack_param.param_hdr.type = response_type;
2706 ack_param.param_hdr.length = htons(sizeof(ack_param) +
2707 err_param_len +
2708 asconf_param_len);
2709 ack_param.crr_id = crr_id;
2710 sctp_addto_chunk(chunk, sizeof(ack_param), &ack_param);
2711
2712 if (SCTP_ERROR_NO_ERROR == err_code)
2713 return;
2714
2715 /* Add Error Cause parameter. */
2716 err_param.cause = err_code;
2717 err_param.length = htons(err_param_len + asconf_param_len);
2718 sctp_addto_chunk(chunk, err_param_len, &err_param);
2719
2720 /* Add the failed TLV copied from ASCONF chunk. */
2721 if (asconf_param)
2722 sctp_addto_chunk(chunk, asconf_param_len, asconf_param);
2723}
2724
2725/* Process a asconf parameter. */
dbc16db1 2726static __be16 sctp_process_asconf_param(struct sctp_association *asoc,
1da177e4
LT		 2727 struct sctp_chunk *asconf,
2728 sctp_addip_param_t *asconf_param)
2729{
2730 struct sctp_transport *peer;
2731 struct sctp_af *af;
2732 union sctp_addr addr;
2733 struct list_head *pos;
2734 union sctp_addr_param *addr_param;
5f242a13 2735
1da177e4
LT		 2736 addr_param = (union sctp_addr_param *)
2737 ((void *)asconf_param + sizeof(sctp_addip_param_t));
2738
2739 af = sctp_get_af_specific(param_type2af(addr_param->v4.param_hdr.type));
2740 if (unlikely(!af))
2741 return SCTP_ERROR_INV_PARAM;
2742
dd86d136 2743 af->from_addr_param(&addr, addr_param, htons(asoc->peer.port), 0);
1da177e4
LT		 2744 switch (asconf_param->param_hdr.type) {
2745 case SCTP_PARAM_ADD_IP:
2746 /* ADDIP 4.3 D9) If an endpoint receives an ADD IP address
d808ad9a
YH		 2747 * request and does not have the local resources to add this
2748 * new address to the association, it MUST return an Error
2749 * Cause TLV set to the new error code 'Operation Refused
2750 * Due to Resource Shortage'.
2751 */
1da177e4 2752
dd86d136 2753 peer = sctp_assoc_add_peer(asoc, &addr, GFP_ATOMIC, SCTP_UNCONFIRMED);
1da177e4
LT		 2754 if (!peer)
2755 return SCTP_ERROR_RSRC_LOW;
2756
2757 /* Start the heartbeat timer. */
2758 if (!mod_timer(&peer->hb_timer, sctp_transport_timeout(peer)))
2759 sctp_transport_hold(peer);
2760 break;
2761 case SCTP_PARAM_DEL_IP:
2762 /* ADDIP 4.3 D7) If a request is received to delete the
d808ad9a
YH		 2763 * last remaining IP address of a peer endpoint, the receiver
2764 * MUST send an Error Cause TLV with the error cause set to the
2765 * new error code 'Request to Delete Last Remaining IP Address'.
2766 */
1da177e4
LT		 2767 pos = asoc->peer.transport_addr_list.next;
2768 if (pos->next == &asoc->peer.transport_addr_list)
2769 return SCTP_ERROR_DEL_LAST_IP;
2770
2771 /* ADDIP 4.3 D8) If a request is received to delete an IP
2772 * address which is also the source address of the IP packet
2773 * which contained the ASCONF chunk, the receiver MUST reject
2774 * this request. To reject the request the receiver MUST send
2775 * an Error Cause TLV set to the new error code 'Request to
2776 * Delete Source IP Address'
2777 */
6a1e5f33 2778 if (sctp_cmp_addr_exact(sctp_source(asconf), &addr))
1da177e4
LT		 2779 return SCTP_ERROR_DEL_SRC_IP;
2780
dd86d136 2781 sctp_assoc_del_peer(asoc, &addr);
1da177e4
LT		 2782 break;
2783 case SCTP_PARAM_SET_PRIMARY:
dd86d136 2784 peer = sctp_assoc_lookup_paddr(asoc, &addr);
1da177e4
LT		 2785 if (!peer)
2786 return SCTP_ERROR_INV_PARAM;
2787
2788 sctp_assoc_set_primary(asoc, peer);
2789 break;
2790 default:
2791 return SCTP_ERROR_INV_PARAM;
2792 break;
2793 }
2794
2795 return SCTP_ERROR_NO_ERROR;
2796}
2797
6f4c618d
WY		 2798/* Verify the ASCONF packet before we process it. */
2799int sctp_verify_asconf(const struct sctp_association *asoc,
2800 struct sctp_paramhdr *param_hdr, void *chunk_end,
2801 struct sctp_paramhdr **errp) {
2802 sctp_addip_param_t *asconf_param;
2803 union sctp_params param;
2804 int length, plen;
2805
2806 param.v = (sctp_paramhdr_t *) param_hdr;
2807 while (param.v <= chunk_end - sizeof(sctp_paramhdr_t)) {
2808 length = ntohs(param.p->length);
2809 *errp = param.p;
2810
2811 if (param.v > chunk_end - length ||
2812 length < sizeof(sctp_paramhdr_t))
2813 return 0;
2814
2815 switch (param.p->type) {
2816 case SCTP_PARAM_ADD_IP:
2817 case SCTP_PARAM_DEL_IP:
2818 case SCTP_PARAM_SET_PRIMARY:
2819 asconf_param = (sctp_addip_param_t *)param.v;
2820 plen = ntohs(asconf_param->param_hdr.length);
2821 if (plen < sizeof(sctp_addip_param_t) +
2822 sizeof(sctp_paramhdr_t))
2823 return 0;
2824 break;
2825 case SCTP_PARAM_SUCCESS_REPORT:
2826 case SCTP_PARAM_ADAPTATION_LAYER_IND:
2827 if (length != sizeof(sctp_addip_param_t))
2828 return 0;
2829
2830 break;
2831 default:
2832 break;
2833 }
2834
2835 param.v += WORD_ROUND(length);
2836 }
2837
2838 if (param.v != chunk_end)
2839 return 0;
2840
2841 return 1;
2842}
2843
d808ad9a 2844/* Process an incoming ASCONF chunk with the next expected serial no. and
1da177e4
LT		 2845 * return an ASCONF_ACK chunk to be sent in response.
2846 */
2847struct sctp_chunk *sctp_process_asconf(struct sctp_association *asoc,
2848 struct sctp_chunk *asconf)
2849{
2850 sctp_addiphdr_t *hdr;
2851 union sctp_addr_param *addr_param;
2852 sctp_addip_param_t *asconf_param;
2853 struct sctp_chunk *asconf_ack;
2854
dbc16db1 2855 __be16 err_code;
1da177e4
LT		 2856 int length = 0;
2857 int chunk_len = asconf->skb->len;
2858 __u32 serial;
2859 int all_param_pass = 1;
2860
2861 hdr = (sctp_addiphdr_t *)asconf->skb->data;
2862 serial = ntohl(hdr->serial);
2863
d808ad9a 2864 /* Skip the addiphdr and store a pointer to address parameter. */
1da177e4
LT		 2865 length = sizeof(sctp_addiphdr_t);
2866 addr_param = (union sctp_addr_param *)(asconf->skb->data + length);
2867 chunk_len -= length;
2868
2869 /* Skip the address parameter and store a pointer to the first
2870 * asconf paramter.
d808ad9a 2871 */
1da177e4
LT		 2872 length = ntohs(addr_param->v4.param_hdr.length);
2873 asconf_param = (sctp_addip_param_t *)((void *)addr_param + length);
2874 chunk_len -= length;
2875
d808ad9a 2876 /* create an ASCONF_ACK chunk.
1da177e4
LT		 2877 * Based on the definitions of parameters, we know that the size of
2878 * ASCONF_ACK parameters are less than or equal to the twice of ASCONF
2879 * paramters.
2880 */
2881 asconf_ack = sctp_make_asconf_ack(asoc, serial, chunk_len * 2);
2882 if (!asconf_ack)
2883 goto done;
2884
2885 /* Process the TLVs contained within the ASCONF chunk. */
2886 while (chunk_len > 0) {
2887 err_code = sctp_process_asconf_param(asoc, asconf,
2888 asconf_param);
2889 /* ADDIP 4.1 A7)
2890 * If an error response is received for a TLV parameter,
2891 * all TLVs with no response before the failed TLV are
2892 * considered successful if not reported. All TLVs after
2893 * the failed response are considered unsuccessful unless
2894 * a specific success indication is present for the parameter.
2895 */
2896 if (SCTP_ERROR_NO_ERROR != err_code)
2897 all_param_pass = 0;
2898
2899 if (!all_param_pass)
2900 sctp_add_asconf_response(asconf_ack,
2901 asconf_param->crr_id, err_code,
2902 asconf_param);
2903
2904 /* ADDIP 4.3 D11) When an endpoint receiving an ASCONF to add
2905 * an IP address sends an 'Out of Resource' in its response, it
2906 * MUST also fail any subsequent add or delete requests bundled
d808ad9a 2907 * in the ASCONF.
1da177e4
LT		 2908 */
2909 if (SCTP_ERROR_RSRC_LOW == err_code)
2910 goto done;
2911
2912 /* Move to the next ASCONF param. */
2913 length = ntohs(asconf_param->param_hdr.length);
2914 asconf_param = (sctp_addip_param_t *)((void *)asconf_param +
2915 length);
2916 chunk_len -= length;
2917 }
d808ad9a 2918
1da177e4
LT		 2919done:
2920 asoc->peer.addip_serial++;
2921
2922 /* If we are sending a new ASCONF_ACK hold a reference to it in assoc
d808ad9a 2923 * after freeing the reference to old asconf ack if any.
1da177e4
LT		 2924 */
2925 if (asconf_ack) {
2926 if (asoc->addip_last_asconf_ack)
2927 sctp_chunk_free(asoc->addip_last_asconf_ack);
2928
2929 sctp_chunk_hold(asconf_ack);
2930 asoc->addip_last_asconf_ack = asconf_ack;
2931 }
2932
2933 return asconf_ack;
2934}
2935
2936/* Process a asconf parameter that is successfully acked. */
2937static int sctp_asconf_param_success(struct sctp_association *asoc,
2938 sctp_addip_param_t *asconf_param)
2939{
2940 struct sctp_af *af;
2941 union sctp_addr addr;
2942 struct sctp_bind_addr *bp = &asoc->base.bind_addr;
2943 union sctp_addr_param *addr_param;
2944 struct list_head *pos;
2945 struct sctp_transport *transport;
dc022a98 2946 struct sctp_sockaddr_entry *saddr;
1da177e4
LT		 2947 int retval = 0;
2948
2949 addr_param = (union sctp_addr_param *)
2950 ((void *)asconf_param + sizeof(sctp_addip_param_t));
2951
2952 /* We have checked the packet before, so we do not check again. */
2953 af = sctp_get_af_specific(param_type2af(addr_param->v4.param_hdr.type));
dd86d136 2954 af->from_addr_param(&addr, addr_param, htons(bp->port), 0);
1da177e4
LT		 2955
2956 switch (asconf_param->param_hdr.type) {
2957 case SCTP_PARAM_ADD_IP:
559cf710
VY		 2958 /* This is always done in BH context with a socket lock
2959 * held, so the list can not change.
2960 */
2961 list_for_each_entry(saddr, &bp->address_list, list) {
dd86d136 2962 if (sctp_cmp_addr_exact(&saddr->a, &addr))
dc022a98
SS		 2963 saddr->use_as_src = 1;
2964 }
1da177e4
LT		 2965 break;
2966 case SCTP_PARAM_DEL_IP:
559cf710 2967 retval = sctp_del_bind_addr(bp, &addr, call_rcu_bh);
1da177e4
LT		 2968 list_for_each(pos, &asoc->peer.transport_addr_list) {
2969 transport = list_entry(pos, struct sctp_transport,
2970 transports);
dc022a98 2971 dst_release(transport->dst);
1da177e4
LT		 2972 sctp_transport_route(transport, NULL,
2973 sctp_sk(asoc->base.sk));
2974 }
2975 break;
2976 default:
2977 break;
2978 }
2979
2980 return retval;
2981}
2982
2983/* Get the corresponding ASCONF response error code from the ASCONF_ACK chunk
2984 * for the given asconf parameter. If there is no response for this parameter,
d808ad9a 2985 * return the error code based on the third argument 'no_err'.
1da177e4
LT		 2986 * ADDIP 4.1
2987 * A7) If an error response is received for a TLV parameter, all TLVs with no
2988 * response before the failed TLV are considered successful if not reported.
2989 * All TLVs after the failed response are considered unsuccessful unless a
2990 * specific success indication is present for the parameter.
2991 */
dbc16db1 2992static __be16 sctp_get_asconf_response(struct sctp_chunk *asconf_ack,
1da177e4
LT		 2993 sctp_addip_param_t *asconf_param,
2994 int no_err)
2995{
2996 sctp_addip_param_t *asconf_ack_param;
2997 sctp_errhdr_t *err_param;
2998 int length;
2999 int asconf_ack_len = asconf_ack->skb->len;
dbc16db1 3000 __be16 err_code;
1da177e4
LT		 3001
3002 if (no_err)
3003 err_code = SCTP_ERROR_NO_ERROR;
3004 else
3005 err_code = SCTP_ERROR_REQ_REFUSED;
3006
3007 /* Skip the addiphdr from the asconf_ack chunk and store a pointer to
3008 * the first asconf_ack parameter.
d808ad9a 3009 */
1da177e4
LT		 3010 length = sizeof(sctp_addiphdr_t);
3011 asconf_ack_param = (sctp_addip_param_t *)(asconf_ack->skb->data +
3012 length);
3013 asconf_ack_len -= length;
3014
3015 while (asconf_ack_len > 0) {
3016 if (asconf_ack_param->crr_id == asconf_param->crr_id) {
3017 switch(asconf_ack_param->param_hdr.type) {
3018 case SCTP_PARAM_SUCCESS_REPORT:
3019 return SCTP_ERROR_NO_ERROR;
3020 case SCTP_PARAM_ERR_CAUSE:
3021 length = sizeof(sctp_addip_param_t);
3022 err_param = (sctp_errhdr_t *)
3023 ((void *)asconf_ack_param + length);
3024 asconf_ack_len -= length;
3025 if (asconf_ack_len > 0)
3026 return err_param->cause;
3027 else
3028 return SCTP_ERROR_INV_PARAM;
3029 break;
3030 default:
3031 return SCTP_ERROR_INV_PARAM;
3032 }
3033 }
3034
3035 length = ntohs(asconf_ack_param->param_hdr.length);
3036 asconf_ack_param = (sctp_addip_param_t *)
3037 ((void *)asconf_ack_param + length);
3038 asconf_ack_len -= length;
3039 }
3040
3041 return err_code;
3042}
3043
3044/* Process an incoming ASCONF_ACK chunk against the cached last ASCONF chunk. */
3045int sctp_process_asconf_ack(struct sctp_association *asoc,
3046 struct sctp_chunk *asconf_ack)
3047{
3048 struct sctp_chunk *asconf = asoc->addip_last_asconf;
3049 union sctp_addr_param *addr_param;
3050 sctp_addip_param_t *asconf_param;
3051 int length = 0;
3052 int asconf_len = asconf->skb->len;
3053 int all_param_pass = 0;
3054 int no_err = 1;
3055 int retval = 0;
dbc16db1 3056 __be16 err_code = SCTP_ERROR_NO_ERROR;
1da177e4
LT		 3057
3058 /* Skip the chunkhdr and addiphdr from the last asconf sent and store
3059 * a pointer to address parameter.
d808ad9a 3060 */
1da177e4
LT		 3061 length = sizeof(sctp_addip_chunk_t);
3062 addr_param = (union sctp_addr_param *)(asconf->skb->data + length);
3063 asconf_len -= length;
3064
3065 /* Skip the address parameter in the last asconf sent and store a
3066 * pointer to the first asconf paramter.
d808ad9a 3067 */
1da177e4
LT		 3068 length = ntohs(addr_param->v4.param_hdr.length);
3069 asconf_param = (sctp_addip_param_t *)((void *)addr_param + length);
3070 asconf_len -= length;
3071
3072 /* ADDIP 4.1
3073 * A8) If there is no response(s) to specific TLV parameter(s), and no
3074 * failures are indicated, then all request(s) are considered
3075 * successful.
3076 */
3077 if (asconf_ack->skb->len == sizeof(sctp_addiphdr_t))
3078 all_param_pass = 1;
3079
3080 /* Process the TLVs contained in the last sent ASCONF chunk. */
3081 while (asconf_len > 0) {
3082 if (all_param_pass)
3083 err_code = SCTP_ERROR_NO_ERROR;
3084 else {
3085 err_code = sctp_get_asconf_response(asconf_ack,
3086 asconf_param,
3087 no_err);
3088 if (no_err && (SCTP_ERROR_NO_ERROR != err_code))
3089 no_err = 0;
3090 }
3091
3092 switch (err_code) {
3093 case SCTP_ERROR_NO_ERROR:
3094 retval = sctp_asconf_param_success(asoc, asconf_param);
3095 break;
3096
3097 case SCTP_ERROR_RSRC_LOW:
3098 retval = 1;
3099 break;
3100
3101 case SCTP_ERROR_INV_PARAM:
3102 /* Disable sending this type of asconf parameter in
3103 * future.
d808ad9a 3104 */
1da177e4
LT		 3105 asoc->peer.addip_disabled_mask |=
3106 asconf_param->param_hdr.type;
3107 break;
3108
3109 case SCTP_ERROR_REQ_REFUSED:
3110 case SCTP_ERROR_DEL_LAST_IP:
3111 case SCTP_ERROR_DEL_SRC_IP:
3112 default:
3113 break;
3114 }
3115
3116 /* Skip the processed asconf parameter and move to the next
3117 * one.
d808ad9a 3118 */
1da177e4
LT		 3119 length = ntohs(asconf_param->param_hdr.length);
3120 asconf_param = (sctp_addip_param_t *)((void *)asconf_param +
3121 length);
3122 asconf_len -= length;
3123 }
3124
3125 /* Free the cached last sent asconf chunk. */
3126 sctp_chunk_free(asconf);
3127 asoc->addip_last_asconf = NULL;
3128
3129 /* Send the next asconf chunk from the addip chunk queue. */
79af02c2
DM		 3130 if (!list_empty(&asoc->addip_chunk_list)) {
3131 struct list_head *entry = asoc->addip_chunk_list.next;
3132 asconf = list_entry(entry, struct sctp_chunk, list);
3133
3134 list_del_init(entry);
3135
1da177e4
LT		 3136 /* Hold the chunk until an ASCONF_ACK is received. */
3137 sctp_chunk_hold(asconf);
3138 if (sctp_primitive_ASCONF(asoc, asconf))
3139 sctp_chunk_free(asconf);
3140 else
3141 asoc->addip_last_asconf = asconf;
3142 }
3143
3144 return retval;
3145}
3146
d808ad9a 3147/* Make a FWD TSN chunk. */
1da177e4
LT		 3148struct sctp_chunk *sctp_make_fwdtsn(const struct sctp_association *asoc,
3149 __u32 new_cum_tsn, size_t nstreams,
3150 struct sctp_fwdtsn_skip *skiplist)
3151{
3152 struct sctp_chunk *retval = NULL;
3153 struct sctp_fwdtsn_chunk *ftsn_chunk;
d808ad9a 3154 struct sctp_fwdtsn_hdr ftsn_hdr;
1da177e4
LT		 3155 struct sctp_fwdtsn_skip skip;
3156 size_t hint;
3157 int i;
3158
3159 hint = (nstreams + 1) * sizeof(__u32);
3160
1da177e4
LT		 3161 retval = sctp_make_chunk(asoc, SCTP_CID_FWD_TSN, 0, hint);
3162
3163 if (!retval)
3164 return NULL;
3165
3166 ftsn_chunk = (struct sctp_fwdtsn_chunk *)retval->subh.fwdtsn_hdr;
3167
3168 ftsn_hdr.new_cum_tsn = htonl(new_cum_tsn);
3169 retval->subh.fwdtsn_hdr =
3170 sctp_addto_chunk(retval, sizeof(ftsn_hdr), &ftsn_hdr);
3171
3172 for (i = 0; i < nstreams; i++) {
3173 skip.stream = skiplist[i].stream;
3174 skip.ssn = skiplist[i].ssn;
3175 sctp_addto_chunk(retval, sizeof(skip), &skip);
3176 }
3177
3178 return retval;
3179}
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