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Merge git://git.kernel.org/pub/scm/linux/kernel/git/hskinnemoen/avr32-2.6
[linux-2.6/mini2440.git] / net / sctp / sm_make_chunk.c
blob6851ee94e974a76530d3f7587a4c7be064290b13
1 /* SCTP kernel 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 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 * This SCTP 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 * This SCTP 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 <linux/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
68 SCTP_STATIC
69 struct sctp_chunk *sctp_make_chunk(const struct sctp_association *asoc,
70 __u8 type, __u8 flags, int paylen);
71 static 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);
76 static int sctp_process_param(struct sctp_association *asoc,
77 union sctp_params param,
78 const union sctp_addr *peer_addr,
79 gfp_t gfp);
80 static void *sctp_addto_param(struct sctp_chunk *chunk, int len,
81 const void *data);
82
83 /* What was the inbound interface for this chunk? */
84 int sctp_chunk_iif(const struct sctp_chunk *chunk)
85 {
86 struct sctp_af *af;
87 int iif = 0;
88
89 af = sctp_get_af_specific(ipver2af(ip_hdr(chunk->skb)->version));
90 if (af)
91 iif = af->skb_iif(chunk->skb);
92
93 return iif;
94 }
95
96 /* RFC 2960 3.3.2 Initiation (INIT) (1)
97 *
98 * Note 2: The ECN capable field is reserved for future use of
99 * Explicit Congestion Notification.
100 */
101 static const struct sctp_paramhdr ecap_param = {
102 SCTP_PARAM_ECN_CAPABLE,
103 cpu_to_be16(sizeof(struct sctp_paramhdr)),
104 };
105 static const struct sctp_paramhdr prsctp_param = {
106 SCTP_PARAM_FWD_TSN_SUPPORT,
107 cpu_to_be16(sizeof(struct sctp_paramhdr)),
108 };
109
110 /* A helper to initialize to initialize an op error inside a
111 * provided chunk, as most cause codes will be embedded inside an
112 * abort chunk.
113 */
114 void sctp_init_cause(struct sctp_chunk *chunk, __be16 cause_code,
115 size_t paylen)
116 {
117 sctp_errhdr_t err;
118 __u16 len;
119
120 /* Cause code constants are now defined in network order. */
121 err.cause = cause_code;
122 len = sizeof(sctp_errhdr_t) + paylen;
123 err.length = htons(len);
124 chunk->subh.err_hdr = sctp_addto_chunk(chunk, sizeof(sctp_errhdr_t), &err);
125 }
126
127 /* 3.3.2 Initiation (INIT) (1)
128 *
129 * This chunk is used to initiate a SCTP association between two
130 * endpoints. The format of the INIT chunk is shown below:
131 *
132 * 0 1 2 3
133 * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
134 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
135 * | Type = 1 | Chunk Flags | Chunk Length |
136 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
137 * | Initiate Tag |
138 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
139 * | Advertised Receiver Window Credit (a_rwnd) |
140 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
141 * | Number of Outbound Streams | Number of Inbound Streams |
142 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
143 * | Initial TSN |
144 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
145 * \ \
146 * / Optional/Variable-Length Parameters /
147 * \ \
148 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
149 *
150 *
151 * The INIT chunk contains the following parameters. Unless otherwise
152 * noted, each parameter MUST only be included once in the INIT chunk.
153 *
154 * Fixed Parameters Status
155 * ----------------------------------------------
156 * Initiate Tag Mandatory
157 * Advertised Receiver Window Credit Mandatory
158 * Number of Outbound Streams Mandatory
159 * Number of Inbound Streams Mandatory
160 * Initial TSN Mandatory
161 *
162 * Variable Parameters Status Type Value
163 * -------------------------------------------------------------
164 * IPv4 Address (Note 1) Optional 5
165 * IPv6 Address (Note 1) Optional 6
166 * Cookie Preservative Optional 9
167 * Reserved for ECN Capable (Note 2) Optional 32768 (0x8000)
168 * Host Name Address (Note 3) Optional 11
169 * Supported Address Types (Note 4) Optional 12
170 */
171 struct sctp_chunk *sctp_make_init(const struct sctp_association *asoc,
172 const struct sctp_bind_addr *bp,
173 gfp_t gfp, int vparam_len)
174 {
175 sctp_inithdr_t init;
176 union sctp_params addrs;
177 size_t chunksize;
178 struct sctp_chunk *retval = NULL;
179 int num_types, addrs_len = 0;
180 struct sctp_sock *sp;
181 sctp_supported_addrs_param_t sat;
182 __be16 types[2];
183 sctp_adaptation_ind_param_t aiparam;
184 sctp_supported_ext_param_t ext_param;
185 int num_ext = 0;
186 __u8 extensions[3];
187 sctp_paramhdr_t *auth_chunks = NULL,
188 *auth_hmacs = NULL;
189
190 /* RFC 2960 3.3.2 Initiation (INIT) (1)
191 *
192 * Note 1: The INIT chunks can contain multiple addresses that
193 * can be IPv4 and/or IPv6 in any combination.
194 */
195 retval = NULL;
196
197 /* Convert the provided bind address list to raw format. */
198 addrs = sctp_bind_addrs_to_raw(bp, &addrs_len, gfp);
199
200 init.init_tag = htonl(asoc->c.my_vtag);
201 init.a_rwnd = htonl(asoc->rwnd);
202 init.num_outbound_streams = htons(asoc->c.sinit_num_ostreams);
203 init.num_inbound_streams = htons(asoc->c.sinit_max_instreams);
204 init.initial_tsn = htonl(asoc->c.initial_tsn);
205
206 /* How many address types are needed? */
207 sp = sctp_sk(asoc->base.sk);
208 num_types = sp->pf->supported_addrs(sp, types);
209
210 chunksize = sizeof(init) + addrs_len + SCTP_SAT_LEN(num_types);
211 chunksize += sizeof(ecap_param);
212
213 if (sctp_prsctp_enable)
214 chunksize += sizeof(prsctp_param);
215
216 /* ADDIP: Section 4.2.7:
217 * An implementation supporting this extension [ADDIP] MUST list
218 * the ASCONF,the ASCONF-ACK, and the AUTH chunks in its INIT and
219 * INIT-ACK parameters.
220 */
221 if (sctp_addip_enable) {
222 extensions[num_ext] = SCTP_CID_ASCONF;
223 extensions[num_ext+1] = SCTP_CID_ASCONF_ACK;
224 num_ext += 2;
225 }
226
227 if (sp->adaptation_ind)
228 chunksize += sizeof(aiparam);
229
230 chunksize += vparam_len;
231
232 /* Account for AUTH related parameters */
233 if (sctp_auth_enable) {
234 /* Add random parameter length*/
235 chunksize += sizeof(asoc->c.auth_random);
236
237 /* Add HMACS parameter length if any were defined */
238 auth_hmacs = (sctp_paramhdr_t *)asoc->c.auth_hmacs;
239 if (auth_hmacs->length)
240 chunksize += ntohs(auth_hmacs->length);
241 else
242 auth_hmacs = NULL;
243
244 /* Add CHUNKS parameter length */
245 auth_chunks = (sctp_paramhdr_t *)asoc->c.auth_chunks;
246 if (auth_chunks->length)
247 chunksize += ntohs(auth_chunks->length);
248 else
249 auth_chunks = NULL;
250
251 extensions[num_ext] = SCTP_CID_AUTH;
252 num_ext += 1;
253 }
254
255 /* If we have any extensions to report, account for that */
256 if (num_ext)
257 chunksize += sizeof(sctp_supported_ext_param_t) + num_ext;
258
259 /* RFC 2960 3.3.2 Initiation (INIT) (1)
260 *
261 * Note 3: An INIT chunk MUST NOT contain more than one Host
262 * Name address parameter. Moreover, the sender of the INIT
263 * MUST NOT combine any other address types with the Host Name
264 * address in the INIT. The receiver of INIT MUST ignore any
265 * other address types if the Host Name address parameter is
266 * present in the received INIT chunk.
267 *
268 * PLEASE DO NOT FIXME [This version does not support Host Name.]
269 */
270
271 retval = sctp_make_chunk(asoc, SCTP_CID_INIT, 0, chunksize);
272 if (!retval)
273 goto nodata;
274
275 retval->subh.init_hdr =
276 sctp_addto_chunk(retval, sizeof(init), &init);
277 retval->param_hdr.v =
278 sctp_addto_chunk(retval, addrs_len, addrs.v);
279
280 /* RFC 2960 3.3.2 Initiation (INIT) (1)
281 *
282 * Note 4: This parameter, when present, specifies all the
283 * address types the sending endpoint can support. The absence
284 * of this parameter indicates that the sending endpoint can
285 * support any address type.
286 */
287 sat.param_hdr.type = SCTP_PARAM_SUPPORTED_ADDRESS_TYPES;
288 sat.param_hdr.length = htons(SCTP_SAT_LEN(num_types));
289 sctp_addto_chunk(retval, sizeof(sat), &sat);
290 sctp_addto_chunk(retval, num_types * sizeof(__u16), &types);
291
292 sctp_addto_chunk(retval, sizeof(ecap_param), &ecap_param);
293
294 /* Add the supported extensions parameter. Be nice and add this
295 * fist before addiding the parameters for the extensions themselves
296 */
297 if (num_ext) {
298 ext_param.param_hdr.type = SCTP_PARAM_SUPPORTED_EXT;
299 ext_param.param_hdr.length =
300 htons(sizeof(sctp_supported_ext_param_t) + num_ext);
301 sctp_addto_chunk(retval, sizeof(sctp_supported_ext_param_t),
302 &ext_param);
303 sctp_addto_param(retval, num_ext, extensions);
304 }
305
306 if (sctp_prsctp_enable)
307 sctp_addto_chunk(retval, sizeof(prsctp_param), &prsctp_param);
308
309 if (sp->adaptation_ind) {
310 aiparam.param_hdr.type = SCTP_PARAM_ADAPTATION_LAYER_IND;
311 aiparam.param_hdr.length = htons(sizeof(aiparam));
312 aiparam.adaptation_ind = htonl(sp->adaptation_ind);
313 sctp_addto_chunk(retval, sizeof(aiparam), &aiparam);
314 }
315
316 /* Add SCTP-AUTH chunks to the parameter list */
317 if (sctp_auth_enable) {
318 sctp_addto_chunk(retval, sizeof(asoc->c.auth_random),
319 asoc->c.auth_random);
320 if (auth_hmacs)
321 sctp_addto_chunk(retval, ntohs(auth_hmacs->length),
322 auth_hmacs);
323 if (auth_chunks)
324 sctp_addto_chunk(retval, ntohs(auth_chunks->length),
325 auth_chunks);
326 }
327 nodata:
328 kfree(addrs.v);
329 return retval;
330 }
331
332 struct sctp_chunk *sctp_make_init_ack(const struct sctp_association *asoc,
333 const struct sctp_chunk *chunk,
334 gfp_t gfp, int unkparam_len)
335 {
336 sctp_inithdr_t initack;
337 struct sctp_chunk *retval;
338 union sctp_params addrs;
339 struct sctp_sock *sp;
340 int addrs_len;
341 sctp_cookie_param_t *cookie;
342 int cookie_len;
343 size_t chunksize;
344 sctp_adaptation_ind_param_t aiparam;
345 sctp_supported_ext_param_t ext_param;
346 int num_ext = 0;
347 __u8 extensions[3];
348 sctp_paramhdr_t *auth_chunks = NULL,
349 *auth_hmacs = NULL,
350 *auth_random = NULL;
351
352 retval = NULL;
353
354 /* Note: there may be no addresses to embed. */
355 addrs = sctp_bind_addrs_to_raw(&asoc->base.bind_addr, &addrs_len, gfp);
356
357 initack.init_tag = htonl(asoc->c.my_vtag);
358 initack.a_rwnd = htonl(asoc->rwnd);
359 initack.num_outbound_streams = htons(asoc->c.sinit_num_ostreams);
360 initack.num_inbound_streams = htons(asoc->c.sinit_max_instreams);
361 initack.initial_tsn = htonl(asoc->c.initial_tsn);
362
363 /* FIXME: We really ought to build the cookie right
364 * into the packet instead of allocating more fresh memory.
365 */
366 cookie = sctp_pack_cookie(asoc->ep, asoc, chunk, &cookie_len,
367 addrs.v, addrs_len);
368 if (!cookie)
369 goto nomem_cookie;
370
371 /* Calculate the total size of allocation, include the reserved
372 * space for reporting unknown parameters if it is specified.
373 */
374 sp = sctp_sk(asoc->base.sk);
375 chunksize = sizeof(initack) + addrs_len + cookie_len + unkparam_len;
376
377 /* Tell peer that we'll do ECN only if peer advertised such cap. */
378 if (asoc->peer.ecn_capable)
379 chunksize += sizeof(ecap_param);
380
381 if (asoc->peer.prsctp_capable)
382 chunksize += sizeof(prsctp_param);
383
384 if (asoc->peer.asconf_capable) {
385 extensions[num_ext] = SCTP_CID_ASCONF;
386 extensions[num_ext+1] = SCTP_CID_ASCONF_ACK;
387 num_ext += 2;
388 }
389
390 if (sp->adaptation_ind)
391 chunksize += sizeof(aiparam);
392
393 if (asoc->peer.auth_capable) {
394 auth_random = (sctp_paramhdr_t *)asoc->c.auth_random;
395 chunksize += ntohs(auth_random->length);
396
397 auth_hmacs = (sctp_paramhdr_t *)asoc->c.auth_hmacs;
398 if (auth_hmacs->length)
399 chunksize += ntohs(auth_hmacs->length);
400 else
401 auth_hmacs = NULL;
402
403 auth_chunks = (sctp_paramhdr_t *)asoc->c.auth_chunks;
404 if (auth_chunks->length)
405 chunksize += ntohs(auth_chunks->length);
406 else
407 auth_chunks = NULL;
408
409 extensions[num_ext] = SCTP_CID_AUTH;
410 num_ext += 1;
411 }
412
413 if (num_ext)
414 chunksize += sizeof(sctp_supported_ext_param_t) + num_ext;
415
416 /* Now allocate and fill out the chunk. */
417 retval = sctp_make_chunk(asoc, SCTP_CID_INIT_ACK, 0, chunksize);
418 if (!retval)
419 goto nomem_chunk;
420
421 /* Per the advice in RFC 2960 6.4, send this reply to
422 * the source of the INIT packet.
423 */
424 retval->transport = chunk->transport;
425 retval->subh.init_hdr =
426 sctp_addto_chunk(retval, sizeof(initack), &initack);
427 retval->param_hdr.v = sctp_addto_chunk(retval, addrs_len, addrs.v);
428 sctp_addto_chunk(retval, cookie_len, cookie);
429 if (asoc->peer.ecn_capable)
430 sctp_addto_chunk(retval, sizeof(ecap_param), &ecap_param);
431 if (num_ext) {
432 ext_param.param_hdr.type = SCTP_PARAM_SUPPORTED_EXT;
433 ext_param.param_hdr.length =
434 htons(sizeof(sctp_supported_ext_param_t) + num_ext);
435 sctp_addto_chunk(retval, sizeof(sctp_supported_ext_param_t),
436 &ext_param);
437 sctp_addto_param(retval, num_ext, extensions);
438 }
439 if (asoc->peer.prsctp_capable)
440 sctp_addto_chunk(retval, sizeof(prsctp_param), &prsctp_param);
441
442 if (sp->adaptation_ind) {
443 aiparam.param_hdr.type = SCTP_PARAM_ADAPTATION_LAYER_IND;
444 aiparam.param_hdr.length = htons(sizeof(aiparam));
445 aiparam.adaptation_ind = htonl(sp->adaptation_ind);
446 sctp_addto_chunk(retval, sizeof(aiparam), &aiparam);
447 }
448
449 if (asoc->peer.auth_capable) {
450 sctp_addto_chunk(retval, ntohs(auth_random->length),
451 auth_random);
452 if (auth_hmacs)
453 sctp_addto_chunk(retval, ntohs(auth_hmacs->length),
454 auth_hmacs);
455 if (auth_chunks)
456 sctp_addto_chunk(retval, ntohs(auth_chunks->length),
457 auth_chunks);
458 }
459
460 /* We need to remove the const qualifier at this point. */
461 retval->asoc = (struct sctp_association *) asoc;
462
463 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
464 *
465 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
466 * HEARTBEAT ACK, * etc.) to the same destination transport
467 * address from which it received the DATA or control chunk
468 * to which it is replying.
469 *
470 * [INIT ACK back to where the INIT came from.]
471 */
472 if (chunk)
473 retval->transport = chunk->transport;
474
475 nomem_chunk:
476 kfree(cookie);
477 nomem_cookie:
478 kfree(addrs.v);
479 return retval;
480 }
481
482 /* 3.3.11 Cookie Echo (COOKIE ECHO) (10):
483 *
484 * This chunk is used only during the initialization of an association.
485 * It is sent by the initiator of an association to its peer to complete
486 * the initialization process. This chunk MUST precede any DATA chunk
487 * sent within the association, but MAY be bundled with one or more DATA
488 * chunks in the same packet.
489 *
490 * 0 1 2 3
491 * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
492 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
493 * | Type = 10 |Chunk Flags | Length |
494 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
495 * / Cookie /
496 * \ \
497 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
498 *
499 * Chunk Flags: 8 bit
500 *
501 * Set to zero on transmit and ignored on receipt.
502 *
503 * Length: 16 bits (unsigned integer)
504 *
505 * Set to the size of the chunk in bytes, including the 4 bytes of
506 * the chunk header and the size of the Cookie.
507 *
508 * Cookie: variable size
509 *
510 * This field must contain the exact cookie received in the
511 * State Cookie parameter from the previous INIT ACK.
512 *
513 * An implementation SHOULD make the cookie as small as possible
514 * to insure interoperability.
515 */
516 struct sctp_chunk *sctp_make_cookie_echo(const struct sctp_association *asoc,
517 const struct sctp_chunk *chunk)
518 {
519 struct sctp_chunk *retval;
520 void *cookie;
521 int cookie_len;
522
523 cookie = asoc->peer.cookie;
524 cookie_len = asoc->peer.cookie_len;
525
526 /* Build a cookie echo chunk. */
527 retval = sctp_make_chunk(asoc, SCTP_CID_COOKIE_ECHO, 0, cookie_len);
528 if (!retval)
529 goto nodata;
530 retval->subh.cookie_hdr =
531 sctp_addto_chunk(retval, cookie_len, cookie);
532
533 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
534 *
535 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
536 * HEARTBEAT ACK, * etc.) to the same destination transport
537 * address from which it * received the DATA or control chunk
538 * to which it is replying.
539 *
540 * [COOKIE ECHO back to where the INIT ACK came from.]
541 */
542 if (chunk)
543 retval->transport = chunk->transport;
544
545 nodata:
546 return retval;
547 }
548
549 /* 3.3.12 Cookie Acknowledgement (COOKIE ACK) (11):
550 *
551 * This chunk is used only during the initialization of an
552 * association. It is used to acknowledge the receipt of a COOKIE
553 * ECHO chunk. This chunk MUST precede any DATA or SACK chunk sent
554 * within the association, but MAY be bundled with one or more DATA
555 * chunks or SACK chunk in the same SCTP packet.
556 *
557 * 0 1 2 3
558 * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
559 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
560 * | Type = 11 |Chunk Flags | Length = 4 |
561 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
562 *
563 * Chunk Flags: 8 bits
564 *
565 * Set to zero on transmit and ignored on receipt.
566 */
567 struct sctp_chunk *sctp_make_cookie_ack(const struct sctp_association *asoc,
568 const struct sctp_chunk *chunk)
569 {
570 struct sctp_chunk *retval;
571
572 retval = sctp_make_chunk(asoc, SCTP_CID_COOKIE_ACK, 0, 0);
573
574 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
575 *
576 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
577 * HEARTBEAT ACK, * etc.) to the same destination transport
578 * address from which it * received the DATA or control chunk
579 * to which it is replying.
580 *
581 * [COOKIE ACK back to where the COOKIE ECHO came from.]
582 */
583 if (retval && chunk)
584 retval->transport = chunk->transport;
585
586 return retval;
587 }
588
589 /*
590 * Appendix A: Explicit Congestion Notification:
591 * CWR:
592 *
593 * RFC 2481 details a specific bit for a sender to send in the header of
594 * its next outbound TCP segment to indicate to its peer that it has
595 * reduced its congestion window. This is termed the CWR bit. For
596 * SCTP the same indication is made by including the CWR chunk.
597 * This chunk contains one data element, i.e. the TSN number that
598 * was sent in the ECNE chunk. This element represents the lowest
599 * TSN number in the datagram that was originally marked with the
600 * CE bit.
601 *
602 * 0 1 2 3
603 * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
604 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
605 * | Chunk Type=13 | Flags=00000000| Chunk Length = 8 |
606 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
607 * | Lowest TSN Number |
608 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
609 *
610 * Note: The CWR is considered a Control chunk.
611 */
612 struct sctp_chunk *sctp_make_cwr(const struct sctp_association *asoc,
613 const __u32 lowest_tsn,
614 const struct sctp_chunk *chunk)
615 {
616 struct sctp_chunk *retval;
617 sctp_cwrhdr_t cwr;
618
619 cwr.lowest_tsn = htonl(lowest_tsn);
620 retval = sctp_make_chunk(asoc, SCTP_CID_ECN_CWR, 0,
621 sizeof(sctp_cwrhdr_t));
622
623 if (!retval)
624 goto nodata;
625
626 retval->subh.ecn_cwr_hdr =
627 sctp_addto_chunk(retval, sizeof(cwr), &cwr);
628
629 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
630 *
631 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
632 * HEARTBEAT ACK, * etc.) to the same destination transport
633 * address from which it * received the DATA or control chunk
634 * to which it is replying.
635 *
636 * [Report a reduced congestion window back to where the ECNE
637 * came from.]
638 */
639 if (chunk)
640 retval->transport = chunk->transport;
641
642 nodata:
643 return retval;
644 }
645
646 /* Make an ECNE chunk. This is a congestion experienced report. */
647 struct sctp_chunk *sctp_make_ecne(const struct sctp_association *asoc,
648 const __u32 lowest_tsn)
649 {
650 struct sctp_chunk *retval;
651 sctp_ecnehdr_t ecne;
652
653 ecne.lowest_tsn = htonl(lowest_tsn);
654 retval = sctp_make_chunk(asoc, SCTP_CID_ECN_ECNE, 0,
655 sizeof(sctp_ecnehdr_t));
656 if (!retval)
657 goto nodata;
658 retval->subh.ecne_hdr =
659 sctp_addto_chunk(retval, sizeof(ecne), &ecne);
660
661 nodata:
662 return retval;
663 }
664
665 /* Make a DATA chunk for the given association from the provided
666 * parameters. However, do not populate the data payload.
667 */
668 struct sctp_chunk *sctp_make_datafrag_empty(struct sctp_association *asoc,
669 const struct sctp_sndrcvinfo *sinfo,
670 int data_len, __u8 flags, __u16 ssn)
671 {
672 struct sctp_chunk *retval;
673 struct sctp_datahdr dp;
674 int chunk_len;
675
676 /* We assign the TSN as LATE as possible, not here when
677 * creating the chunk.
678 */
679 dp.tsn = 0;
680 dp.stream = htons(sinfo->sinfo_stream);
681 dp.ppid = sinfo->sinfo_ppid;
682
683 /* Set the flags for an unordered send. */
684 if (sinfo->sinfo_flags & SCTP_UNORDERED) {
685 flags |= SCTP_DATA_UNORDERED;
686 dp.ssn = 0;
687 } else
688 dp.ssn = htons(ssn);
689
690 chunk_len = sizeof(dp) + data_len;
691 retval = sctp_make_chunk(asoc, SCTP_CID_DATA, flags, chunk_len);
692 if (!retval)
693 goto nodata;
694
695 retval->subh.data_hdr = sctp_addto_chunk(retval, sizeof(dp), &dp);
696 memcpy(&retval->sinfo, sinfo, sizeof(struct sctp_sndrcvinfo));
697
698 nodata:
699 return retval;
700 }
701
702 /* Create a selective ackowledgement (SACK) for the given
703 * association. This reports on which TSN's we've seen to date,
704 * including duplicates and gaps.
705 */
706 struct sctp_chunk *sctp_make_sack(const struct sctp_association *asoc)
707 {
708 struct sctp_chunk *retval;
709 struct sctp_sackhdr sack;
710 int len;
711 __u32 ctsn;
712 __u16 num_gabs, num_dup_tsns;
713 struct sctp_tsnmap *map = (struct sctp_tsnmap *)&asoc->peer.tsn_map;
714 struct sctp_gap_ack_block gabs[SCTP_MAX_GABS];
715
716 memset(gabs, 0, sizeof(gabs));
717 ctsn = sctp_tsnmap_get_ctsn(map);
718 SCTP_DEBUG_PRINTK("sackCTSNAck sent: 0x%x.\n", ctsn);
719
720 /* How much room is needed in the chunk? */
721 num_gabs = sctp_tsnmap_num_gabs(map, gabs);
722 num_dup_tsns = sctp_tsnmap_num_dups(map);
723
724 /* Initialize the SACK header. */
725 sack.cum_tsn_ack = htonl(ctsn);
726 sack.a_rwnd = htonl(asoc->a_rwnd);
727 sack.num_gap_ack_blocks = htons(num_gabs);
728 sack.num_dup_tsns = htons(num_dup_tsns);
729
730 len = sizeof(sack)
731 + sizeof(struct sctp_gap_ack_block) * num_gabs
732 + sizeof(__u32) * num_dup_tsns;
733
734 /* Create the chunk. */
735 retval = sctp_make_chunk(asoc, SCTP_CID_SACK, 0, len);
736 if (!retval)
737 goto nodata;
738
739 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
740 *
741 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
742 * HEARTBEAT ACK, etc.) to the same destination transport
743 * address from which it received the DATA or control chunk to
744 * which it is replying. This rule should also be followed if
745 * the endpoint is bundling DATA chunks together with the
746 * reply chunk.
747 *
748 * However, when acknowledging multiple DATA chunks received
749 * in packets from different source addresses in a single
750 * SACK, the SACK chunk may be transmitted to one of the
751 * destination transport addresses from which the DATA or
752 * control chunks being acknowledged were received.
753 *
754 * [BUG: We do not implement the following paragraph.
755 * Perhaps we should remember the last transport we used for a
756 * SACK and avoid that (if possible) if we have seen any
757 * duplicates. --piggy]
758 *
759 * When a receiver of a duplicate DATA chunk sends a SACK to a
760 * multi- homed endpoint it MAY be beneficial to vary the
761 * destination address and not use the source address of the
762 * DATA chunk. The reason being that receiving a duplicate
763 * from a multi-homed endpoint might indicate that the return
764 * path (as specified in the source address of the DATA chunk)
765 * for the SACK is broken.
766 *
767 * [Send to the address from which we last received a DATA chunk.]
768 */
769 retval->transport = asoc->peer.last_data_from;
770
771 retval->subh.sack_hdr =
772 sctp_addto_chunk(retval, sizeof(sack), &sack);
773
774 /* Add the gap ack block information. */
775 if (num_gabs)
776 sctp_addto_chunk(retval, sizeof(__u32) * num_gabs,
777 gabs);
778
779 /* Add the duplicate TSN information. */
780 if (num_dup_tsns)
781 sctp_addto_chunk(retval, sizeof(__u32) * num_dup_tsns,
782 sctp_tsnmap_get_dups(map));
783
784 nodata:
785 return retval;
786 }
787
788 /* Make a SHUTDOWN chunk. */
789 struct sctp_chunk *sctp_make_shutdown(const struct sctp_association *asoc,
790 const struct sctp_chunk *chunk)
791 {
792 struct sctp_chunk *retval;
793 sctp_shutdownhdr_t shut;
794 __u32 ctsn;
795
796 ctsn = sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map);
797 shut.cum_tsn_ack = htonl(ctsn);
798
799 retval = sctp_make_chunk(asoc, SCTP_CID_SHUTDOWN, 0,
800 sizeof(sctp_shutdownhdr_t));
801 if (!retval)
802 goto nodata;
803
804 retval->subh.shutdown_hdr =
805 sctp_addto_chunk(retval, sizeof(shut), &shut);
806
807 if (chunk)
808 retval->transport = chunk->transport;
809 nodata:
810 return retval;
811 }
812
813 struct sctp_chunk *sctp_make_shutdown_ack(const struct sctp_association *asoc,
814 const struct sctp_chunk *chunk)
815 {
816 struct sctp_chunk *retval;
817
818 retval = sctp_make_chunk(asoc, SCTP_CID_SHUTDOWN_ACK, 0, 0);
819
820 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
821 *
822 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
823 * HEARTBEAT ACK, * etc.) to the same destination transport
824 * address from which it * received the DATA or control chunk
825 * to which it is replying.
826 *
827 * [ACK back to where the SHUTDOWN came from.]
828 */
829 if (retval && chunk)
830 retval->transport = chunk->transport;
831
832 return retval;
833 }
834
835 struct sctp_chunk *sctp_make_shutdown_complete(
836 const struct sctp_association *asoc,
837 const struct sctp_chunk *chunk)
838 {
839 struct sctp_chunk *retval;
840 __u8 flags = 0;
841
842 /* Set the T-bit if we have no association (vtag will be
843 * reflected)
844 */
845 flags |= asoc ? 0 : SCTP_CHUNK_FLAG_T;
846
847 retval = sctp_make_chunk(asoc, SCTP_CID_SHUTDOWN_COMPLETE, flags, 0);
848
849 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
850 *
851 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
852 * HEARTBEAT ACK, * etc.) to the same destination transport
853 * address from which it * received the DATA or control chunk
854 * to which it is replying.
855 *
856 * [Report SHUTDOWN COMPLETE back to where the SHUTDOWN ACK
857 * came from.]
858 */
859 if (retval && chunk)
860 retval->transport = chunk->transport;
861
862 return retval;
863 }
864
865 /* Create an ABORT. Note that we set the T bit if we have no
866 * association, except when responding to an INIT (sctpimpguide 2.41).
867 */
868 struct sctp_chunk *sctp_make_abort(const struct sctp_association *asoc,
869 const struct sctp_chunk *chunk,
870 const size_t hint)
871 {
872 struct sctp_chunk *retval;
873 __u8 flags = 0;
874
875 /* Set the T-bit if we have no association and 'chunk' is not
876 * an INIT (vtag will be reflected).
877 */
878 if (!asoc) {
879 if (chunk && chunk->chunk_hdr &&
880 chunk->chunk_hdr->type == SCTP_CID_INIT)
881 flags = 0;
882 else
883 flags = SCTP_CHUNK_FLAG_T;
884 }
885
886 retval = sctp_make_chunk(asoc, SCTP_CID_ABORT, flags, hint);
887
888 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
889 *
890 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
891 * HEARTBEAT ACK, * etc.) to the same destination transport
892 * address from which it * received the DATA or control chunk
893 * to which it is replying.
894 *
895 * [ABORT back to where the offender came from.]
896 */
897 if (retval && chunk)
898 retval->transport = chunk->transport;
899
900 return retval;
901 }
902
903 /* Helper to create ABORT with a NO_USER_DATA error. */
904 struct sctp_chunk *sctp_make_abort_no_data(
905 const struct sctp_association *asoc,
906 const struct sctp_chunk *chunk, __u32 tsn)
907 {
908 struct sctp_chunk *retval;
909 __be32 payload;
910
911 retval = sctp_make_abort(asoc, chunk, sizeof(sctp_errhdr_t)
912 + sizeof(tsn));
913
914 if (!retval)
915 goto no_mem;
916
917 /* Put the tsn back into network byte order. */
918 payload = htonl(tsn);
919 sctp_init_cause(retval, SCTP_ERROR_NO_DATA, sizeof(payload));
920 sctp_addto_chunk(retval, sizeof(payload), (const void *)&payload);
921
922 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
923 *
924 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
925 * HEARTBEAT ACK, * etc.) to the same destination transport
926 * address from which it * received the DATA or control chunk
927 * to which it is replying.
928 *
929 * [ABORT back to where the offender came from.]
930 */
931 if (chunk)
932 retval->transport = chunk->transport;
933
934 no_mem:
935 return retval;
936 }
937
938 /* Helper to create ABORT with a SCTP_ERROR_USER_ABORT error. */
939 struct sctp_chunk *sctp_make_abort_user(const struct sctp_association *asoc,
940 const struct msghdr *msg,
941 size_t paylen)
942 {
943 struct sctp_chunk *retval;
944 void *payload = NULL;
945 int err;
946
947 retval = sctp_make_abort(asoc, NULL, sizeof(sctp_errhdr_t) + paylen);
948 if (!retval)
949 goto err_chunk;
950
951 if (paylen) {
952 /* Put the msg_iov together into payload. */
953 payload = kmalloc(paylen, GFP_KERNEL);
954 if (!payload)
955 goto err_payload;
956
957 err = memcpy_fromiovec(payload, msg->msg_iov, paylen);
958 if (err < 0)
959 goto err_copy;
960 }
961
962 sctp_init_cause(retval, SCTP_ERROR_USER_ABORT, paylen);
963 sctp_addto_chunk(retval, paylen, payload);
964
965 if (paylen)
966 kfree(payload);
967
968 return retval;
969
970 err_copy:
971 kfree(payload);
972 err_payload:
973 sctp_chunk_free(retval);
974 retval = NULL;
975 err_chunk:
976 return retval;
977 }
978
979 /* Append bytes to the end of a parameter. Will panic if chunk is not big
980 * enough.
981 */
982 static void *sctp_addto_param(struct sctp_chunk *chunk, int len,
983 const void *data)
984 {
985 void *target;
986 int chunklen = ntohs(chunk->chunk_hdr->length);
987
988 target = skb_put(chunk->skb, len);
989
990 memcpy(target, data, len);
991
992 /* Adjust the chunk length field. */
993 chunk->chunk_hdr->length = htons(chunklen + len);
994 chunk->chunk_end = skb_tail_pointer(chunk->skb);
995
996 return target;
997 }
998
999 /* Make an ABORT chunk with a PROTOCOL VIOLATION cause code. */
1000 struct sctp_chunk *sctp_make_abort_violation(
1001 const struct sctp_association *asoc,
1002 const struct sctp_chunk *chunk,
1003 const __u8 *payload,
1004 const size_t paylen)
1005 {
1006 struct sctp_chunk *retval;
1007 struct sctp_paramhdr phdr;
1008
1009 retval = sctp_make_abort(asoc, chunk, sizeof(sctp_errhdr_t) + paylen
1010 + sizeof(sctp_paramhdr_t));
1011 if (!retval)
1012 goto end;
1013
1014 sctp_init_cause(retval, SCTP_ERROR_PROTO_VIOLATION, paylen
1015 + sizeof(sctp_paramhdr_t));
1016
1017 phdr.type = htons(chunk->chunk_hdr->type);
1018 phdr.length = chunk->chunk_hdr->length;
1019 sctp_addto_chunk(retval, paylen, payload);
1020 sctp_addto_param(retval, sizeof(sctp_paramhdr_t), &phdr);
1021
1022 end:
1023 return retval;
1024 }
1025
1026 struct sctp_chunk *sctp_make_violation_paramlen(
1027 const struct sctp_association *asoc,
1028 const struct sctp_chunk *chunk,
1029 struct sctp_paramhdr *param)
1030 {
1031 struct sctp_chunk *retval;
1032 static const char error[] = "The following parameter had invalid length:";
1033 size_t payload_len = sizeof(error) + sizeof(sctp_errhdr_t) +
1034 sizeof(sctp_paramhdr_t);
1035
1036 retval = sctp_make_abort(asoc, chunk, payload_len);
1037 if (!retval)
1038 goto nodata;
1039
1040 sctp_init_cause(retval, SCTP_ERROR_PROTO_VIOLATION,
1041 sizeof(error) + sizeof(sctp_paramhdr_t));
1042 sctp_addto_chunk(retval, sizeof(error), error);
1043 sctp_addto_param(retval, sizeof(sctp_paramhdr_t), param);
1044
1045 nodata:
1046 return retval;
1047 }
1048
1049 /* Make a HEARTBEAT chunk. */
1050 struct sctp_chunk *sctp_make_heartbeat(const struct sctp_association *asoc,
1051 const struct sctp_transport *transport,
1052 const void *payload, const size_t paylen)
1053 {
1054 struct sctp_chunk *retval = sctp_make_chunk(asoc, SCTP_CID_HEARTBEAT,
1055 0, paylen);
1056
1057 if (!retval)
1058 goto nodata;
1059
1060 /* Cast away the 'const', as this is just telling the chunk
1061 * what transport it belongs to.
1062 */
1063 retval->transport = (struct sctp_transport *) transport;
1064 retval->subh.hbs_hdr = sctp_addto_chunk(retval, paylen, payload);
1065
1066 nodata:
1067 return retval;
1068 }
1069
1070 struct sctp_chunk *sctp_make_heartbeat_ack(const struct sctp_association *asoc,
1071 const struct sctp_chunk *chunk,
1072 const void *payload, const size_t paylen)
1073 {
1074 struct sctp_chunk *retval;
1075
1076 retval = sctp_make_chunk(asoc, SCTP_CID_HEARTBEAT_ACK, 0, paylen);
1077 if (!retval)
1078 goto nodata;
1079
1080 retval->subh.hbs_hdr = sctp_addto_chunk(retval, paylen, payload);
1081
1082 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
1083 *
1084 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
1085 * HEARTBEAT ACK, * etc.) to the same destination transport
1086 * address from which it * received the DATA or control chunk
1087 * to which it is replying.
1088 *
1089 * [HBACK back to where the HEARTBEAT came from.]
1090 */
1091 if (chunk)
1092 retval->transport = chunk->transport;
1093
1094 nodata:
1095 return retval;
1096 }
1097
1098 /* Create an Operation Error chunk with the specified space reserved.
1099 * This routine can be used for containing multiple causes in the chunk.
1100 */
1101 static struct sctp_chunk *sctp_make_op_error_space(
1102 const struct sctp_association *asoc,
1103 const struct sctp_chunk *chunk,
1104 size_t size)
1105 {
1106 struct sctp_chunk *retval;
1107
1108 retval = sctp_make_chunk(asoc, SCTP_CID_ERROR, 0,
1109 sizeof(sctp_errhdr_t) + size);
1110 if (!retval)
1111 goto nodata;
1112
1113 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
1114 *
1115 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
1116 * HEARTBEAT ACK, etc.) to the same destination transport
1117 * address from which it received the DATA or control chunk
1118 * to which it is replying.
1119 *
1120 */
1121 if (chunk)
1122 retval->transport = chunk->transport;
1123
1124 nodata:
1125 return retval;
1126 }
1127
1128 /* Create an Operation Error chunk. */
1129 struct sctp_chunk *sctp_make_op_error(const struct sctp_association *asoc,
1130 const struct sctp_chunk *chunk,
1131 __be16 cause_code, const void *payload,
1132 size_t paylen)
1133 {
1134 struct sctp_chunk *retval;
1135
1136 retval = sctp_make_op_error_space(asoc, chunk, paylen);
1137 if (!retval)
1138 goto nodata;
1139
1140 sctp_init_cause(retval, cause_code, paylen);
1141 sctp_addto_chunk(retval, paylen, payload);
1142
1143 nodata:
1144 return retval;
1145 }
1146
1147 struct sctp_chunk *sctp_make_auth(const struct sctp_association *asoc)
1148 {
1149 struct sctp_chunk *retval;
1150 struct sctp_hmac *hmac_desc;
1151 struct sctp_authhdr auth_hdr;
1152 __u8 *hmac;
1153
1154 /* Get the first hmac that the peer told us to use */
1155 hmac_desc = sctp_auth_asoc_get_hmac(asoc);
1156 if (unlikely(!hmac_desc))
1157 return NULL;
1158
1159 retval = sctp_make_chunk(asoc, SCTP_CID_AUTH, 0,
1160 hmac_desc->hmac_len + sizeof(sctp_authhdr_t));
1161 if (!retval)
1162 return NULL;
1163
1164 auth_hdr.hmac_id = htons(hmac_desc->hmac_id);
1165 auth_hdr.shkey_id = htons(asoc->active_key_id);
1166
1167 retval->subh.auth_hdr = sctp_addto_chunk(retval, sizeof(sctp_authhdr_t),
1168 &auth_hdr);
1169
1170 hmac = skb_put(retval->skb, hmac_desc->hmac_len);
1171 memset(hmac, 0, hmac_desc->hmac_len);
1172
1173 /* Adjust the chunk header to include the empty MAC */
1174 retval->chunk_hdr->length =
1175 htons(ntohs(retval->chunk_hdr->length) + hmac_desc->hmac_len);
1176 retval->chunk_end = skb_tail_pointer(retval->skb);
1177
1178 return retval;
1179 }
1180
1181
1182 /********************************************************************
1183 * 2nd Level Abstractions
1184 ********************************************************************/
1185
1186 /* Turn an skb into a chunk.
1187 * FIXME: Eventually move the structure directly inside the skb->cb[].
1188 */
1189 struct sctp_chunk *sctp_chunkify(struct sk_buff *skb,
1190 const struct sctp_association *asoc,
1191 struct sock *sk)
1192 {
1193 struct sctp_chunk *retval;
1194
1195 retval = kmem_cache_zalloc(sctp_chunk_cachep, GFP_ATOMIC);
1196
1197 if (!retval)
1198 goto nodata;
1199
1200 if (!sk) {
1201 SCTP_DEBUG_PRINTK("chunkifying skb %p w/o an sk\n", skb);
1202 }
1203
1204 INIT_LIST_HEAD(&retval->list);
1205 retval->skb = skb;
1206 retval->asoc = (struct sctp_association *)asoc;
1207 retval->resent = 0;
1208 retval->has_tsn = 0;
1209 retval->has_ssn = 0;
1210 retval->rtt_in_progress = 0;
1211 retval->sent_at = 0;
1212 retval->singleton = 1;
1213 retval->end_of_packet = 0;
1214 retval->ecn_ce_done = 0;
1215 retval->pdiscard = 0;
1216
1217 /* sctpimpguide-05.txt Section 2.8.2
1218 * M1) Each time a new DATA chunk is transmitted
1219 * set the 'TSN.Missing.Report' count for that TSN to 0. The
1220 * 'TSN.Missing.Report' count will be used to determine missing chunks
1221 * and when to fast retransmit.
1222 */
1223 retval->tsn_missing_report = 0;
1224 retval->tsn_gap_acked = 0;
1225 retval->fast_retransmit = SCTP_CAN_FRTX;
1226
1227 /* If this is a fragmented message, track all fragments
1228 * of the message (for SEND_FAILED).
1229 */
1230 retval->msg = NULL;
1231
1232 /* Polish the bead hole. */
1233 INIT_LIST_HEAD(&retval->transmitted_list);
1234 INIT_LIST_HEAD(&retval->frag_list);
1235 SCTP_DBG_OBJCNT_INC(chunk);
1236 atomic_set(&retval->refcnt, 1);
1237
1238 nodata:
1239 return retval;
1240 }
1241
1242 /* Set chunk->source and dest based on the IP header in chunk->skb. */
1243 void sctp_init_addrs(struct sctp_chunk *chunk, union sctp_addr *src,
1244 union sctp_addr *dest)
1245 {
1246 memcpy(&chunk->source, src, sizeof(union sctp_addr));
1247 memcpy(&chunk->dest, dest, sizeof(union sctp_addr));
1248 }
1249
1250 /* Extract the source address from a chunk. */
1251 const union sctp_addr *sctp_source(const struct sctp_chunk *chunk)
1252 {
1253 /* If we have a known transport, use that. */
1254 if (chunk->transport) {
1255 return &chunk->transport->ipaddr;
1256 } else {
1257 /* Otherwise, extract it from the IP header. */
1258 return &chunk->source;
1259 }
1260 }
1261
1262 /* Create a new chunk, setting the type and flags headers from the
1263 * arguments, reserving enough space for a 'paylen' byte payload.
1264 */
1265 SCTP_STATIC
1266 struct sctp_chunk *sctp_make_chunk(const struct sctp_association *asoc,
1267 __u8 type, __u8 flags, int paylen)
1268 {
1269 struct sctp_chunk *retval;
1270 sctp_chunkhdr_t *chunk_hdr;
1271 struct sk_buff *skb;
1272 struct sock *sk;
1273
1274 /* No need to allocate LL here, as this is only a chunk. */
1275 skb = alloc_skb(WORD_ROUND(sizeof(sctp_chunkhdr_t) + paylen),
1276 GFP_ATOMIC);
1277 if (!skb)
1278 goto nodata;
1279
1280 /* Make room for the chunk header. */
1281 chunk_hdr = (sctp_chunkhdr_t *)skb_put(skb, sizeof(sctp_chunkhdr_t));
1282 chunk_hdr->type = type;
1283 chunk_hdr->flags = flags;
1284 chunk_hdr->length = htons(sizeof(sctp_chunkhdr_t));
1285
1286 sk = asoc ? asoc->base.sk : NULL;
1287 retval = sctp_chunkify(skb, asoc, sk);
1288 if (!retval) {
1289 kfree_skb(skb);
1290 goto nodata;
1291 }
1292
1293 retval->chunk_hdr = chunk_hdr;
1294 retval->chunk_end = ((__u8 *)chunk_hdr) + sizeof(struct sctp_chunkhdr);
1295
1296 /* Determine if the chunk needs to be authenticated */
1297 if (sctp_auth_send_cid(type, asoc))
1298 retval->auth = 1;
1299
1300 /* Set the skb to the belonging sock for accounting. */
1301 skb->sk = sk;
1302
1303 return retval;
1304 nodata:
1305 return NULL;
1306 }
1307
1308
1309 /* Release the memory occupied by a chunk. */
1310 static void sctp_chunk_destroy(struct sctp_chunk *chunk)
1311 {
1312 BUG_ON(!list_empty(&chunk->list));
1313 list_del_init(&chunk->transmitted_list);
1314
1315 /* Free the chunk skb data and the SCTP_chunk stub itself. */
1316 dev_kfree_skb(chunk->skb);
1317
1318 SCTP_DBG_OBJCNT_DEC(chunk);
1319 kmem_cache_free(sctp_chunk_cachep, chunk);
1320 }
1321
1322 /* Possibly, free the chunk. */
1323 void sctp_chunk_free(struct sctp_chunk *chunk)
1324 {
1325 /* Release our reference on the message tracker. */
1326 if (chunk->msg)
1327 sctp_datamsg_put(chunk->msg);
1328
1329 sctp_chunk_put(chunk);
1330 }
1331
1332 /* Grab a reference to the chunk. */
1333 void sctp_chunk_hold(struct sctp_chunk *ch)
1334 {
1335 atomic_inc(&ch->refcnt);
1336 }
1337
1338 /* Release a reference to the chunk. */
1339 void sctp_chunk_put(struct sctp_chunk *ch)
1340 {
1341 if (atomic_dec_and_test(&ch->refcnt))
1342 sctp_chunk_destroy(ch);
1343 }
1344
1345 /* Append bytes to the end of a chunk. Will panic if chunk is not big
1346 * enough.
1347 */
1348 void *sctp_addto_chunk(struct sctp_chunk *chunk, int len, const void *data)
1349 {
1350 void *target;
1351 void *padding;
1352 int chunklen = ntohs(chunk->chunk_hdr->length);
1353 int padlen = WORD_ROUND(chunklen) - chunklen;
1354
1355 padding = skb_put(chunk->skb, padlen);
1356 target = skb_put(chunk->skb, len);
1357
1358 memset(padding, 0, padlen);
1359 memcpy(target, data, len);
1360
1361 /* Adjust the chunk length field. */
1362 chunk->chunk_hdr->length = htons(chunklen + padlen + len);
1363 chunk->chunk_end = skb_tail_pointer(chunk->skb);
1364
1365 return target;
1366 }
1367
1368 /* Append bytes from user space to the end of a chunk. Will panic if
1369 * chunk is not big enough.
1370 * Returns a kernel err value.
1371 */
1372 int sctp_user_addto_chunk(struct sctp_chunk *chunk, int off, int len,
1373 struct iovec *data)
1374 {
1375 __u8 *target;
1376 int err = 0;
1377
1378 /* Make room in chunk for data. */
1379 target = skb_put(chunk->skb, len);
1380
1381 /* Copy data (whole iovec) into chunk */
1382 if ((err = memcpy_fromiovecend(target, data, off, len)))
1383 goto out;
1384
1385 /* Adjust the chunk length field. */
1386 chunk->chunk_hdr->length =
1387 htons(ntohs(chunk->chunk_hdr->length) + len);
1388 chunk->chunk_end = skb_tail_pointer(chunk->skb);
1389
1390 out:
1391 return err;
1392 }
1393
1394 /* Helper function to assign a TSN if needed. This assumes that both
1395 * the data_hdr and association have already been assigned.
1396 */
1397 void sctp_chunk_assign_ssn(struct sctp_chunk *chunk)
1398 {
1399 struct sctp_datamsg *msg;
1400 struct sctp_chunk *lchunk;
1401 struct sctp_stream *stream;
1402 __u16 ssn;
1403 __u16 sid;
1404
1405 if (chunk->has_ssn)
1406 return;
1407
1408 /* All fragments will be on the same stream */
1409 sid = ntohs(chunk->subh.data_hdr->stream);
1410 stream = &chunk->asoc->ssnmap->out;
1411
1412 /* Now assign the sequence number to the entire message.
1413 * All fragments must have the same stream sequence number.
1414 */
1415 msg = chunk->msg;
1416 list_for_each_entry(lchunk, &msg->chunks, frag_list) {
1417 if (lchunk->chunk_hdr->flags & SCTP_DATA_UNORDERED) {
1418 ssn = 0;
1419 } else {
1420 if (lchunk->chunk_hdr->flags & SCTP_DATA_LAST_FRAG)
1421 ssn = sctp_ssn_next(stream, sid);
1422 else
1423 ssn = sctp_ssn_peek(stream, sid);
1424 }
1425
1426 lchunk->subh.data_hdr->ssn = htons(ssn);
1427 lchunk->has_ssn = 1;
1428 }
1429 }
1430
1431 /* Helper function to assign a TSN if needed. This assumes that both
1432 * the data_hdr and association have already been assigned.
1433 */
1434 void sctp_chunk_assign_tsn(struct sctp_chunk *chunk)
1435 {
1436 if (!chunk->has_tsn) {
1437 /* This is the last possible instant to
1438 * assign a TSN.
1439 */
1440 chunk->subh.data_hdr->tsn =
1441 htonl(sctp_association_get_next_tsn(chunk->asoc));
1442 chunk->has_tsn = 1;
1443 }
1444 }
1445
1446 /* Create a CLOSED association to use with an incoming packet. */
1447 struct sctp_association *sctp_make_temp_asoc(const struct sctp_endpoint *ep,
1448 struct sctp_chunk *chunk,
1449 gfp_t gfp)
1450 {
1451 struct sctp_association *asoc;
1452 struct sk_buff *skb;
1453 sctp_scope_t scope;
1454 struct sctp_af *af;
1455
1456 /* Create the bare association. */
1457 scope = sctp_scope(sctp_source(chunk));
1458 asoc = sctp_association_new(ep, ep->base.sk, scope, gfp);
1459 if (!asoc)
1460 goto nodata;
1461 asoc->temp = 1;
1462 skb = chunk->skb;
1463 /* Create an entry for the source address of the packet. */
1464 af = sctp_get_af_specific(ipver2af(ip_hdr(skb)->version));
1465 if (unlikely(!af))
1466 goto fail;
1467 af->from_skb(&asoc->c.peer_addr, skb, 1);
1468 nodata:
1469 return asoc;
1470
1471 fail:
1472 sctp_association_free(asoc);
1473 return NULL;
1474 }
1475
1476 /* Build a cookie representing asoc.
1477 * This INCLUDES the param header needed to put the cookie in the INIT ACK.
1478 */
1479 static sctp_cookie_param_t *sctp_pack_cookie(const struct sctp_endpoint *ep,
1480 const struct sctp_association *asoc,
1481 const struct sctp_chunk *init_chunk,
1482 int *cookie_len,
1483 const __u8 *raw_addrs, int addrs_len)
1484 {
1485 sctp_cookie_param_t *retval;
1486 struct sctp_signed_cookie *cookie;
1487 struct scatterlist sg;
1488 int headersize, bodysize;
1489 unsigned int keylen;
1490 char *key;
1491
1492 /* Header size is static data prior to the actual cookie, including
1493 * any padding.
1494 */
1495 headersize = sizeof(sctp_paramhdr_t) +
1496 (sizeof(struct sctp_signed_cookie) -
1497 sizeof(struct sctp_cookie));
1498 bodysize = sizeof(struct sctp_cookie)
1499 + ntohs(init_chunk->chunk_hdr->length) + addrs_len;
1500
1501 /* Pad out the cookie to a multiple to make the signature
1502 * functions simpler to write.
1503 */
1504 if (bodysize % SCTP_COOKIE_MULTIPLE)
1505 bodysize += SCTP_COOKIE_MULTIPLE
1506 - (bodysize % SCTP_COOKIE_MULTIPLE);
1507 *cookie_len = headersize + bodysize;
1508
1509 /* Clear this memory since we are sending this data structure
1510 * out on the network.
1511 */
1512 retval = kzalloc(*cookie_len, GFP_ATOMIC);
1513 if (!retval)
1514 goto nodata;
1515
1516 cookie = (struct sctp_signed_cookie *) retval->body;
1517
1518 /* Set up the parameter header. */
1519 retval->p.type = SCTP_PARAM_STATE_COOKIE;
1520 retval->p.length = htons(*cookie_len);
1521
1522 /* Copy the cookie part of the association itself. */
1523 cookie->c = asoc->c;
1524 /* Save the raw address list length in the cookie. */
1525 cookie->c.raw_addr_list_len = addrs_len;
1526
1527 /* Remember PR-SCTP capability. */
1528 cookie->c.prsctp_capable = asoc->peer.prsctp_capable;
1529
1530 /* Save adaptation indication in the cookie. */
1531 cookie->c.adaptation_ind = asoc->peer.adaptation_ind;
1532
1533 /* Set an expiration time for the cookie. */
1534 do_gettimeofday(&cookie->c.expiration);
1535 TIMEVAL_ADD(asoc->cookie_life, cookie->c.expiration);
1536
1537 /* Copy the peer's init packet. */
1538 memcpy(&cookie->c.peer_init[0], init_chunk->chunk_hdr,
1539 ntohs(init_chunk->chunk_hdr->length));
1540
1541 /* Copy the raw local address list of the association. */
1542 memcpy((__u8 *)&cookie->c.peer_init[0] +
1543 ntohs(init_chunk->chunk_hdr->length), raw_addrs, addrs_len);
1544
1545 if (sctp_sk(ep->base.sk)->hmac) {
1546 struct hash_desc desc;
1547
1548 /* Sign the message. */
1549 sg_init_one(&sg, &cookie->c, bodysize);
1550 keylen = SCTP_SECRET_SIZE;
1551 key = (char *)ep->secret_key[ep->current_key];
1552 desc.tfm = sctp_sk(ep->base.sk)->hmac;
1553 desc.flags = 0;
1554
1555 if (crypto_hash_setkey(desc.tfm, key, keylen) ||
1556 crypto_hash_digest(&desc, &sg, bodysize, cookie->signature))
1557 goto free_cookie;
1558 }
1559
1560 return retval;
1561
1562 free_cookie:
1563 kfree(retval);
1564 nodata:
1565 *cookie_len = 0;
1566 return NULL;
1567 }
1568
1569 /* Unpack the cookie from COOKIE ECHO chunk, recreating the association. */
1570 struct sctp_association *sctp_unpack_cookie(
1571 const struct sctp_endpoint *ep,
1572 const struct sctp_association *asoc,
1573 struct sctp_chunk *chunk, gfp_t gfp,
1574 int *error, struct sctp_chunk **errp)
1575 {
1576 struct sctp_association *retval = NULL;
1577 struct sctp_signed_cookie *cookie;
1578 struct sctp_cookie *bear_cookie;
1579 int headersize, bodysize, fixed_size;
1580 __u8 *digest = ep->digest;
1581 struct scatterlist sg;
1582 unsigned int keylen, len;
1583 char *key;
1584 sctp_scope_t scope;
1585 struct sk_buff *skb = chunk->skb;
1586 struct timeval tv;
1587 struct hash_desc desc;
1588
1589 /* Header size is static data prior to the actual cookie, including
1590 * any padding.
1591 */
1592 headersize = sizeof(sctp_chunkhdr_t) +
1593 (sizeof(struct sctp_signed_cookie) -
1594 sizeof(struct sctp_cookie));
1595 bodysize = ntohs(chunk->chunk_hdr->length) - headersize;
1596 fixed_size = headersize + sizeof(struct sctp_cookie);
1597
1598 /* Verify that the chunk looks like it even has a cookie.
1599 * There must be enough room for our cookie and our peer's
1600 * INIT chunk.
1601 */
1602 len = ntohs(chunk->chunk_hdr->length);
1603 if (len < fixed_size + sizeof(struct sctp_chunkhdr))
1604 goto malformed;
1605
1606 /* Verify that the cookie has been padded out. */
1607 if (bodysize % SCTP_COOKIE_MULTIPLE)
1608 goto malformed;
1609
1610 /* Process the cookie. */
1611 cookie = chunk->subh.cookie_hdr;
1612 bear_cookie = &cookie->c;
1613
1614 if (!sctp_sk(ep->base.sk)->hmac)
1615 goto no_hmac;
1616
1617 /* Check the signature. */
1618 keylen = SCTP_SECRET_SIZE;
1619 sg_init_one(&sg, bear_cookie, bodysize);
1620 key = (char *)ep->secret_key[ep->current_key];
1621 desc.tfm = sctp_sk(ep->base.sk)->hmac;
1622 desc.flags = 0;
1623
1624 memset(digest, 0x00, SCTP_SIGNATURE_SIZE);
1625 if (crypto_hash_setkey(desc.tfm, key, keylen) ||
1626 crypto_hash_digest(&desc, &sg, bodysize, digest)) {
1627 *error = -SCTP_IERROR_NOMEM;
1628 goto fail;
1629 }
1630
1631 if (memcmp(digest, cookie->signature, SCTP_SIGNATURE_SIZE)) {
1632 /* Try the previous key. */
1633 key = (char *)ep->secret_key[ep->last_key];
1634 memset(digest, 0x00, SCTP_SIGNATURE_SIZE);
1635 if (crypto_hash_setkey(desc.tfm, key, keylen) ||
1636 crypto_hash_digest(&desc, &sg, bodysize, digest)) {
1637 *error = -SCTP_IERROR_NOMEM;
1638 goto fail;
1639 }
1640
1641 if (memcmp(digest, cookie->signature, SCTP_SIGNATURE_SIZE)) {
1642 /* Yikes! Still bad signature! */
1643 *error = -SCTP_IERROR_BAD_SIG;
1644 goto fail;
1645 }
1646 }
1647
1648 no_hmac:
1649 /* IG Section 2.35.2:
1650 * 3) Compare the port numbers and the verification tag contained
1651 * within the COOKIE ECHO chunk to the actual port numbers and the
1652 * verification tag within the SCTP common header of the received
1653 * packet. If these values do not match the packet MUST be silently
1654 * discarded,
1655 */
1656 if (ntohl(chunk->sctp_hdr->vtag) != bear_cookie->my_vtag) {
1657 *error = -SCTP_IERROR_BAD_TAG;
1658 goto fail;
1659 }
1660
1661 if (chunk->sctp_hdr->source != bear_cookie->peer_addr.v4.sin_port ||
1662 ntohs(chunk->sctp_hdr->dest) != bear_cookie->my_port) {
1663 *error = -SCTP_IERROR_BAD_PORTS;
1664 goto fail;
1665 }
1666
1667 /* Check to see if the cookie is stale. If there is already
1668 * an association, there is no need to check cookie's expiration
1669 * for init collision case of lost COOKIE ACK.
1670 * If skb has been timestamped, then use the stamp, otherwise
1671 * use current time. This introduces a small possibility that
1672 * that a cookie may be considered expired, but his would only slow
1673 * down the new association establishment instead of every packet.
1674 */
1675 if (sock_flag(ep->base.sk, SOCK_TIMESTAMP))
1676 skb_get_timestamp(skb, &tv);
1677 else
1678 do_gettimeofday(&tv);
1679
1680 if (!asoc && tv_lt(bear_cookie->expiration, tv)) {
1681 /*
1682 * Section 3.3.10.3 Stale Cookie Error (3)
1683 *
1684 * Cause of error
1685 * ---------------
1686 * Stale Cookie Error: Indicates the receipt of a valid State
1687 * Cookie that has expired.
1688 */
1689 len = ntohs(chunk->chunk_hdr->length);
1690 *errp = sctp_make_op_error_space(asoc, chunk, len);
1691 if (*errp) {
1692 suseconds_t usecs = (tv.tv_sec -
1693 bear_cookie->expiration.tv_sec) * 1000000L +
1694 tv.tv_usec - bear_cookie->expiration.tv_usec;
1695 __be32 n = htonl(usecs);
1696
1697 sctp_init_cause(*errp, SCTP_ERROR_STALE_COOKIE,
1698 sizeof(n));
1699 sctp_addto_chunk(*errp, sizeof(n), &n);
1700 *error = -SCTP_IERROR_STALE_COOKIE;
1701 } else
1702 *error = -SCTP_IERROR_NOMEM;
1703
1704 goto fail;
1705 }
1706
1707 /* Make a new base association. */
1708 scope = sctp_scope(sctp_source(chunk));
1709 retval = sctp_association_new(ep, ep->base.sk, scope, gfp);
1710 if (!retval) {
1711 *error = -SCTP_IERROR_NOMEM;
1712 goto fail;
1713 }
1714
1715 /* Set up our peer's port number. */
1716 retval->peer.port = ntohs(chunk->sctp_hdr->source);
1717
1718 /* Populate the association from the cookie. */
1719 memcpy(&retval->c, bear_cookie, sizeof(*bear_cookie));
1720
1721 if (sctp_assoc_set_bind_addr_from_cookie(retval, bear_cookie,
1722 GFP_ATOMIC) < 0) {
1723 *error = -SCTP_IERROR_NOMEM;
1724 goto fail;
1725 }
1726
1727 /* Also, add the destination address. */
1728 if (list_empty(&retval->base.bind_addr.address_list)) {
1729 sctp_add_bind_addr(&retval->base.bind_addr, &chunk->dest,
1730 SCTP_ADDR_SRC, GFP_ATOMIC);
1731 }
1732
1733 retval->next_tsn = retval->c.initial_tsn;
1734 retval->ctsn_ack_point = retval->next_tsn - 1;
1735 retval->addip_serial = retval->c.initial_tsn;
1736 retval->adv_peer_ack_point = retval->ctsn_ack_point;
1737 retval->peer.prsctp_capable = retval->c.prsctp_capable;
1738 retval->peer.adaptation_ind = retval->c.adaptation_ind;
1739
1740 /* The INIT stuff will be done by the side effects. */
1741 return retval;
1742
1743 fail:
1744 if (retval)
1745 sctp_association_free(retval);
1746
1747 return NULL;
1748
1749 malformed:
1750 /* Yikes! The packet is either corrupt or deliberately
1751 * malformed.
1752 */
1753 *error = -SCTP_IERROR_MALFORMED;
1754 goto fail;
1755 }
1756
1757 /********************************************************************
1758 * 3rd Level Abstractions
1759 ********************************************************************/
1760
1761 struct __sctp_missing {
1762 __be32 num_missing;
1763 __be16 type;
1764 } __attribute__((packed));
1765
1766 /*
1767 * Report a missing mandatory parameter.
1768 */
1769 static int sctp_process_missing_param(const struct sctp_association *asoc,
1770 sctp_param_t paramtype,
1771 struct sctp_chunk *chunk,
1772 struct sctp_chunk **errp)
1773 {
1774 struct __sctp_missing report;
1775 __u16 len;
1776
1777 len = WORD_ROUND(sizeof(report));
1778
1779 /* Make an ERROR chunk, preparing enough room for
1780 * returning multiple unknown parameters.
1781 */
1782 if (!*errp)
1783 *errp = sctp_make_op_error_space(asoc, chunk, len);
1784
1785 if (*errp) {
1786 report.num_missing = htonl(1);
1787 report.type = paramtype;
1788 sctp_init_cause(*errp, SCTP_ERROR_MISS_PARAM,
1789 sizeof(report));
1790 sctp_addto_chunk(*errp, sizeof(report), &report);
1791 }
1792
1793 /* Stop processing this chunk. */
1794 return 0;
1795 }
1796
1797 /* Report an Invalid Mandatory Parameter. */
1798 static int sctp_process_inv_mandatory(const struct sctp_association *asoc,
1799 struct sctp_chunk *chunk,
1800 struct sctp_chunk **errp)
1801 {
1802 /* Invalid Mandatory Parameter Error has no payload. */
1803
1804 if (!*errp)
1805 *errp = sctp_make_op_error_space(asoc, chunk, 0);
1806
1807 if (*errp)
1808 sctp_init_cause(*errp, SCTP_ERROR_INV_PARAM, 0);
1809
1810 /* Stop processing this chunk. */
1811 return 0;
1812 }
1813
1814 static int sctp_process_inv_paramlength(const struct sctp_association *asoc,
1815 struct sctp_paramhdr *param,
1816 const struct sctp_chunk *chunk,
1817 struct sctp_chunk **errp)
1818 {
1819 /* This is a fatal error. Any accumulated non-fatal errors are
1820 * not reported.
1821 */
1822 if (*errp)
1823 sctp_chunk_free(*errp);
1824
1825 /* Create an error chunk and fill it in with our payload. */
1826 *errp = sctp_make_violation_paramlen(asoc, chunk, param);
1827
1828 return 0;
1829 }
1830
1831
1832 /* Do not attempt to handle the HOST_NAME parm. However, do
1833 * send back an indicator to the peer.
1834 */
1835 static int sctp_process_hn_param(const struct sctp_association *asoc,
1836 union sctp_params param,
1837 struct sctp_chunk *chunk,
1838 struct sctp_chunk **errp)
1839 {
1840 __u16 len = ntohs(param.p->length);
1841
1842 /* Processing of the HOST_NAME parameter will generate an
1843 * ABORT. If we've accumulated any non-fatal errors, they
1844 * would be unrecognized parameters and we should not include
1845 * them in the ABORT.
1846 */
1847 if (*errp)
1848 sctp_chunk_free(*errp);
1849
1850 *errp = sctp_make_op_error_space(asoc, chunk, len);
1851
1852 if (*errp) {
1853 sctp_init_cause(*errp, SCTP_ERROR_DNS_FAILED, len);
1854 sctp_addto_chunk(*errp, len, param.v);
1855 }
1856
1857 /* Stop processing this chunk. */
1858 return 0;
1859 }
1860
1861 static int sctp_verify_ext_param(union sctp_params param)
1862 {
1863 __u16 num_ext = ntohs(param.p->length) - sizeof(sctp_paramhdr_t);
1864 int have_auth = 0;
1865 int have_asconf = 0;
1866 int i;
1867
1868 for (i = 0; i < num_ext; i++) {
1869 switch (param.ext->chunks[i]) {
1870 case SCTP_CID_AUTH:
1871 have_auth = 1;
1872 break;
1873 case SCTP_CID_ASCONF:
1874 case SCTP_CID_ASCONF_ACK:
1875 have_asconf = 1;
1876 break;
1877 }
1878 }
1879
1880 /* ADD-IP Security: The draft requires us to ABORT or ignore the
1881 * INIT/INIT-ACK if ADD-IP is listed, but AUTH is not. Do this
1882 * only if ADD-IP is turned on and we are not backward-compatible
1883 * mode.
1884 */
1885 if (sctp_addip_noauth)
1886 return 1;
1887
1888 if (sctp_addip_enable && !have_auth && have_asconf)
1889 return 0;
1890
1891 return 1;
1892 }
1893
1894 static void sctp_process_ext_param(struct sctp_association *asoc,
1895 union sctp_params param)
1896 {
1897 __u16 num_ext = ntohs(param.p->length) - sizeof(sctp_paramhdr_t);
1898 int i;
1899
1900 for (i = 0; i < num_ext; i++) {
1901 switch (param.ext->chunks[i]) {
1902 case SCTP_CID_FWD_TSN:
1903 if (sctp_prsctp_enable &&
1904 !asoc->peer.prsctp_capable)
1905 asoc->peer.prsctp_capable = 1;
1906 break;
1907 case SCTP_CID_AUTH:
1908 /* if the peer reports AUTH, assume that he
1909 * supports AUTH.
1910 */
1911 if (sctp_auth_enable)
1912 asoc->peer.auth_capable = 1;
1913 break;
1914 case SCTP_CID_ASCONF:
1915 case SCTP_CID_ASCONF_ACK:
1916 if (sctp_addip_enable)
1917 asoc->peer.asconf_capable = 1;
1918 break;
1919 default:
1920 break;
1921 }
1922 }
1923 }
1924
1925 /* RFC 3.2.1 & the Implementers Guide 2.2.
1926 *
1927 * The Parameter Types are encoded such that the
1928 * highest-order two bits specify the action that must be
1929 * taken if the processing endpoint does not recognize the
1930 * Parameter Type.
1931 *
1932 * 00 - Stop processing this parameter; do not process any further
1933 * parameters within this chunk
1934 *
1935 * 01 - Stop processing this parameter, do not process any further
1936 * parameters within this chunk, and report the unrecognized
1937 * parameter in an 'Unrecognized Parameter' ERROR chunk.
1938 *
1939 * 10 - Skip this parameter and continue processing.
1940 *
1941 * 11 - Skip this parameter and continue processing but
1942 * report the unrecognized parameter in an
1943 * 'Unrecognized Parameter' ERROR chunk.
1944 *
1945 * Return value:
1946 * SCTP_IERROR_NO_ERROR - continue with the chunk
1947 * SCTP_IERROR_ERROR - stop and report an error.
1948 * SCTP_IERROR_NOMEME - out of memory.
1949 */
1950 static sctp_ierror_t sctp_process_unk_param(const struct sctp_association *asoc,
1951 union sctp_params param,
1952 struct sctp_chunk *chunk,
1953 struct sctp_chunk **errp)
1954 {
1955 int retval = SCTP_IERROR_NO_ERROR;
1956
1957 switch (param.p->type & SCTP_PARAM_ACTION_MASK) {
1958 case SCTP_PARAM_ACTION_DISCARD:
1959 retval = SCTP_IERROR_ERROR;
1960 break;
1961 case SCTP_PARAM_ACTION_SKIP:
1962 break;
1963 case SCTP_PARAM_ACTION_DISCARD_ERR:
1964 retval = SCTP_IERROR_ERROR;
1965 /* Fall through */
1966 case SCTP_PARAM_ACTION_SKIP_ERR:
1967 /* Make an ERROR chunk, preparing enough room for
1968 * returning multiple unknown parameters.
1969 */
1970 if (NULL == *errp)
1971 *errp = sctp_make_op_error_space(asoc, chunk,
1972 ntohs(chunk->chunk_hdr->length));
1973
1974 if (*errp) {
1975 sctp_init_cause(*errp, SCTP_ERROR_UNKNOWN_PARAM,
1976 WORD_ROUND(ntohs(param.p->length)));
1977 sctp_addto_chunk(*errp,
1978 WORD_ROUND(ntohs(param.p->length)),
1979 param.v);
1980 } else {
1981 /* If there is no memory for generating the ERROR
1982 * report as specified, an ABORT will be triggered
1983 * to the peer and the association won't be
1984 * established.
1985 */
1986 retval = SCTP_IERROR_NOMEM;
1987 }
1988 break;
1989 default:
1990 break;
1991 }
1992
1993 return retval;
1994 }
1995
1996 /* Verify variable length parameters
1997 * Return values:
1998 * SCTP_IERROR_ABORT - trigger an ABORT
1999 * SCTP_IERROR_NOMEM - out of memory (abort)
2000 * SCTP_IERROR_ERROR - stop processing, trigger an ERROR
2001 * SCTP_IERROR_NO_ERROR - continue with the chunk
2002 */
2003 static sctp_ierror_t sctp_verify_param(const struct sctp_association *asoc,
2004 union sctp_params param,
2005 sctp_cid_t cid,
2006 struct sctp_chunk *chunk,
2007 struct sctp_chunk **err_chunk)
2008 {
2009 struct sctp_hmac_algo_param *hmacs;
2010 int retval = SCTP_IERROR_NO_ERROR;
2011 __u16 n_elt, id = 0;
2012 int i;
2013
2014 /* FIXME - This routine is not looking at each parameter per the
2015 * chunk type, i.e., unrecognized parameters should be further
2016 * identified based on the chunk id.
2017 */
2018
2019 switch (param.p->type) {
2020 case SCTP_PARAM_IPV4_ADDRESS:
2021 case SCTP_PARAM_IPV6_ADDRESS:
2022 case SCTP_PARAM_COOKIE_PRESERVATIVE:
2023 case SCTP_PARAM_SUPPORTED_ADDRESS_TYPES:
2024 case SCTP_PARAM_STATE_COOKIE:
2025 case SCTP_PARAM_HEARTBEAT_INFO:
2026 case SCTP_PARAM_UNRECOGNIZED_PARAMETERS:
2027 case SCTP_PARAM_ECN_CAPABLE:
2028 case SCTP_PARAM_ADAPTATION_LAYER_IND:
2029 break;
2030
2031 case SCTP_PARAM_SUPPORTED_EXT:
2032 if (!sctp_verify_ext_param(param))
2033 return SCTP_IERROR_ABORT;
2034 break;
2035
2036 case SCTP_PARAM_SET_PRIMARY:
2037 if (sctp_addip_enable)
2038 break;
2039 goto fallthrough;
2040
2041 case SCTP_PARAM_HOST_NAME_ADDRESS:
2042 /* Tell the peer, we won't support this param. */
2043 sctp_process_hn_param(asoc, param, chunk, err_chunk);
2044 retval = SCTP_IERROR_ABORT;
2045 break;
2046
2047 case SCTP_PARAM_FWD_TSN_SUPPORT:
2048 if (sctp_prsctp_enable)
2049 break;
2050 goto fallthrough;
2051
2052 case SCTP_PARAM_RANDOM:
2053 if (!sctp_auth_enable)
2054 goto fallthrough;
2055
2056 /* SCTP-AUTH: Secion 6.1
2057 * If the random number is not 32 byte long the association
2058 * MUST be aborted. The ABORT chunk SHOULD contain the error
2059 * cause 'Protocol Violation'.
2060 */
2061 if (SCTP_AUTH_RANDOM_LENGTH !=
2062 ntohs(param.p->length) - sizeof(sctp_paramhdr_t)) {
2063 sctp_process_inv_paramlength(asoc, param.p,
2064 chunk, err_chunk);
2065 retval = SCTP_IERROR_ABORT;
2066 }
2067 break;
2068
2069 case SCTP_PARAM_CHUNKS:
2070 if (!sctp_auth_enable)
2071 goto fallthrough;
2072
2073 /* SCTP-AUTH: Section 3.2
2074 * The CHUNKS parameter MUST be included once in the INIT or
2075 * INIT-ACK chunk if the sender wants to receive authenticated
2076 * chunks. Its maximum length is 260 bytes.
2077 */
2078 if (260 < ntohs(param.p->length)) {
2079 sctp_process_inv_paramlength(asoc, param.p,
2080 chunk, err_chunk);
2081 retval = SCTP_IERROR_ABORT;
2082 }
2083 break;
2084
2085 case SCTP_PARAM_HMAC_ALGO:
2086 if (!sctp_auth_enable)
2087 goto fallthrough;
2088
2089 hmacs = (struct sctp_hmac_algo_param *)param.p;
2090 n_elt = (ntohs(param.p->length) - sizeof(sctp_paramhdr_t)) >> 1;
2091
2092 /* SCTP-AUTH: Section 6.1
2093 * The HMAC algorithm based on SHA-1 MUST be supported and
2094 * included in the HMAC-ALGO parameter.
2095 */
2096 for (i = 0; i < n_elt; i++) {
2097 id = ntohs(hmacs->hmac_ids[i]);
2098
2099 if (id == SCTP_AUTH_HMAC_ID_SHA1)
2100 break;
2101 }
2102
2103 if (id != SCTP_AUTH_HMAC_ID_SHA1) {
2104 sctp_process_inv_paramlength(asoc, param.p, chunk,
2105 err_chunk);
2106 retval = SCTP_IERROR_ABORT;
2107 }
2108 break;
2109 fallthrough:
2110 default:
2111 SCTP_DEBUG_PRINTK("Unrecognized param: %d for chunk %d.\n",
2112 ntohs(param.p->type), cid);
2113 retval = sctp_process_unk_param(asoc, param, chunk, err_chunk);
2114 break;
2115 }
2116 return retval;
2117 }
2118
2119 /* Verify the INIT packet before we process it. */
2120 int sctp_verify_init(const struct sctp_association *asoc,
2121 sctp_cid_t cid,
2122 sctp_init_chunk_t *peer_init,
2123 struct sctp_chunk *chunk,
2124 struct sctp_chunk **errp)
2125 {
2126 union sctp_params param;
2127 int has_cookie = 0;
2128 int result;
2129
2130 /* Verify stream values are non-zero. */
2131 if ((0 == peer_init->init_hdr.num_outbound_streams) ||
2132 (0 == peer_init->init_hdr.num_inbound_streams) ||
2133 (0 == peer_init->init_hdr.init_tag) ||
2134 (SCTP_DEFAULT_MINWINDOW > ntohl(peer_init->init_hdr.a_rwnd))) {
2135
2136 return sctp_process_inv_mandatory(asoc, chunk, errp);
2137 }
2138
2139 /* Check for missing mandatory parameters. */
2140 sctp_walk_params(param, peer_init, init_hdr.params) {
2141
2142 if (SCTP_PARAM_STATE_COOKIE == param.p->type)
2143 has_cookie = 1;
2144
2145 } /* for (loop through all parameters) */
2146
2147 /* There is a possibility that a parameter length was bad and
2148 * in that case we would have stoped walking the parameters.
2149 * The current param.p would point at the bad one.
2150 * Current consensus on the mailing list is to generate a PROTOCOL
2151 * VIOLATION error. We build the ERROR chunk here and let the normal
2152 * error handling code build and send the packet.
2153 */
2154 if (param.v != (void*)chunk->chunk_end)
2155 return sctp_process_inv_paramlength(asoc, param.p, chunk, errp);
2156
2157 /* The only missing mandatory param possible today is
2158 * the state cookie for an INIT-ACK chunk.
2159 */
2160 if ((SCTP_CID_INIT_ACK == cid) && !has_cookie)
2161 return sctp_process_missing_param(asoc, SCTP_PARAM_STATE_COOKIE,
2162 chunk, errp);
2163
2164 /* Verify all the variable length parameters */
2165 sctp_walk_params(param, peer_init, init_hdr.params) {
2166
2167 result = sctp_verify_param(asoc, param, cid, chunk, errp);
2168 switch (result) {
2169 case SCTP_IERROR_ABORT:
2170 case SCTP_IERROR_NOMEM:
2171 return 0;
2172 case SCTP_IERROR_ERROR:
2173 return 1;
2174 case SCTP_IERROR_NO_ERROR:
2175 default:
2176 break;
2177 }
2178
2179 } /* for (loop through all parameters) */
2180
2181 return 1;
2182 }
2183
2184 /* Unpack the parameters in an INIT packet into an association.
2185 * Returns 0 on failure, else success.
2186 * FIXME: This is an association method.
2187 */
2188 int sctp_process_init(struct sctp_association *asoc, sctp_cid_t cid,
2189 const union sctp_addr *peer_addr,
2190 sctp_init_chunk_t *peer_init, gfp_t gfp)
2191 {
2192 union sctp_params param;
2193 struct sctp_transport *transport;
2194 struct list_head *pos, *temp;
2195 char *cookie;
2196
2197 /* We must include the address that the INIT packet came from.
2198 * This is the only address that matters for an INIT packet.
2199 * When processing a COOKIE ECHO, we retrieve the from address
2200 * of the INIT from the cookie.
2201 */
2202
2203 /* This implementation defaults to making the first transport
2204 * added as the primary transport. The source address seems to
2205 * be a a better choice than any of the embedded addresses.
2206 */
2207 if (peer_addr) {
2208 if(!sctp_assoc_add_peer(asoc, peer_addr, gfp, SCTP_ACTIVE))
2209 goto nomem;
2210 }
2211
2212 /* Process the initialization parameters. */
2213 sctp_walk_params(param, peer_init, init_hdr.params) {
2214
2215 if (!sctp_process_param(asoc, param, peer_addr, gfp))
2216 goto clean_up;
2217 }
2218
2219 /* AUTH: After processing the parameters, make sure that we
2220 * have all the required info to potentially do authentications.
2221 */
2222 if (asoc->peer.auth_capable && (!asoc->peer.peer_random ||
2223 !asoc->peer.peer_hmacs))
2224 asoc->peer.auth_capable = 0;
2225
2226 /* In a non-backward compatible mode, if the peer claims
2227 * support for ADD-IP but not AUTH, the ADD-IP spec states
2228 * that we MUST ABORT the association. Section 6. The section
2229 * also give us an option to silently ignore the packet, which
2230 * is what we'll do here.
2231 */
2232 if (!sctp_addip_noauth &&
2233 (asoc->peer.asconf_capable && !asoc->peer.auth_capable)) {
2234 asoc->peer.addip_disabled_mask |= (SCTP_PARAM_ADD_IP |
2235 SCTP_PARAM_DEL_IP |
2236 SCTP_PARAM_SET_PRIMARY);
2237 asoc->peer.asconf_capable = 0;
2238 goto clean_up;
2239 }
2240
2241 /* Walk list of transports, removing transports in the UNKNOWN state. */
2242 list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
2243 transport = list_entry(pos, struct sctp_transport, transports);
2244 if (transport->state == SCTP_UNKNOWN) {
2245 sctp_assoc_rm_peer(asoc, transport);
2246 }
2247 }
2248
2249 /* The fixed INIT headers are always in network byte
2250 * order.
2251 */
2252 asoc->peer.i.init_tag =
2253 ntohl(peer_init->init_hdr.init_tag);
2254 asoc->peer.i.a_rwnd =
2255 ntohl(peer_init->init_hdr.a_rwnd);
2256 asoc->peer.i.num_outbound_streams =
2257 ntohs(peer_init->init_hdr.num_outbound_streams);
2258 asoc->peer.i.num_inbound_streams =
2259 ntohs(peer_init->init_hdr.num_inbound_streams);
2260 asoc->peer.i.initial_tsn =
2261 ntohl(peer_init->init_hdr.initial_tsn);
2262
2263 /* Apply the upper bounds for output streams based on peer's
2264 * number of inbound streams.
2265 */
2266 if (asoc->c.sinit_num_ostreams >
2267 ntohs(peer_init->init_hdr.num_inbound_streams)) {
2268 asoc->c.sinit_num_ostreams =
2269 ntohs(peer_init->init_hdr.num_inbound_streams);
2270 }
2271
2272 if (asoc->c.sinit_max_instreams >
2273 ntohs(peer_init->init_hdr.num_outbound_streams)) {
2274 asoc->c.sinit_max_instreams =
2275 ntohs(peer_init->init_hdr.num_outbound_streams);
2276 }
2277
2278 /* Copy Initiation tag from INIT to VT_peer in cookie. */
2279 asoc->c.peer_vtag = asoc->peer.i.init_tag;
2280
2281 /* Peer Rwnd : Current calculated value of the peer's rwnd. */
2282 asoc->peer.rwnd = asoc->peer.i.a_rwnd;
2283
2284 /* Copy cookie in case we need to resend COOKIE-ECHO. */
2285 cookie = asoc->peer.cookie;
2286 if (cookie) {
2287 asoc->peer.cookie = kmemdup(cookie, asoc->peer.cookie_len, gfp);
2288 if (!asoc->peer.cookie)
2289 goto clean_up;
2290 }
2291
2292 /* RFC 2960 7.2.1 The initial value of ssthresh MAY be arbitrarily
2293 * high (for example, implementations MAY use the size of the receiver
2294 * advertised window).
2295 */
2296 list_for_each_entry(transport, &asoc->peer.transport_addr_list,
2297 transports) {
2298 transport->ssthresh = asoc->peer.i.a_rwnd;
2299 }
2300
2301 /* Set up the TSN tracking pieces. */
2302 if (!sctp_tsnmap_init(&asoc->peer.tsn_map, SCTP_TSN_MAP_INITIAL,
2303 asoc->peer.i.initial_tsn, gfp))
2304 goto clean_up;
2305
2306 /* RFC 2960 6.5 Stream Identifier and Stream Sequence Number
2307 *
2308 * The stream sequence number in all the streams shall start
2309 * from 0 when the association is established. Also, when the
2310 * stream sequence number reaches the value 65535 the next
2311 * stream sequence number shall be set to 0.
2312 */
2313
2314 /* Allocate storage for the negotiated streams if it is not a temporary
2315 * association.
2316 */
2317 if (!asoc->temp) {
2318 int error;
2319
2320 asoc->ssnmap = sctp_ssnmap_new(asoc->c.sinit_max_instreams,
2321 asoc->c.sinit_num_ostreams, gfp);
2322 if (!asoc->ssnmap)
2323 goto clean_up;
2324
2325 error = sctp_assoc_set_id(asoc, gfp);
2326 if (error)
2327 goto clean_up;
2328 }
2329
2330 /* ADDIP Section 4.1 ASCONF Chunk Procedures
2331 *
2332 * When an endpoint has an ASCONF signaled change to be sent to the
2333 * remote endpoint it should do the following:
2334 * ...
2335 * A2) A serial number should be assigned to the Chunk. The serial
2336 * number should be a monotonically increasing number. All serial
2337 * numbers are defined to be initialized at the start of the
2338 * association to the same value as the Initial TSN.
2339 */
2340 asoc->peer.addip_serial = asoc->peer.i.initial_tsn - 1;
2341 return 1;
2342
2343 clean_up:
2344 /* Release the transport structures. */
2345 list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
2346 transport = list_entry(pos, struct sctp_transport, transports);
2347 if (transport->state != SCTP_ACTIVE)
2348 sctp_assoc_rm_peer(asoc, transport);
2349 }
2350
2351 nomem:
2352 return 0;
2353 }
2354
2355
2356 /* Update asoc with the option described in param.
2357 *
2358 * RFC2960 3.3.2.1 Optional/Variable Length Parameters in INIT
2359 *
2360 * asoc is the association to update.
2361 * param is the variable length parameter to use for update.
2362 * cid tells us if this is an INIT, INIT ACK or COOKIE ECHO.
2363 * If the current packet is an INIT we want to minimize the amount of
2364 * work we do. In particular, we should not build transport
2365 * structures for the addresses.
2366 */
2367 static int sctp_process_param(struct sctp_association *asoc,
2368 union sctp_params param,
2369 const union sctp_addr *peer_addr,
2370 gfp_t gfp)
2371 {
2372 union sctp_addr addr;
2373 int i;
2374 __u16 sat;
2375 int retval = 1;
2376 sctp_scope_t scope;
2377 time_t stale;
2378 struct sctp_af *af;
2379 union sctp_addr_param *addr_param;
2380 struct sctp_transport *t;
2381
2382 /* We maintain all INIT parameters in network byte order all the
2383 * time. This allows us to not worry about whether the parameters
2384 * came from a fresh INIT, and INIT ACK, or were stored in a cookie.
2385 */
2386 switch (param.p->type) {
2387 case SCTP_PARAM_IPV6_ADDRESS:
2388 if (PF_INET6 != asoc->base.sk->sk_family)
2389 break;
2390 goto do_addr_param;
2391
2392 case SCTP_PARAM_IPV4_ADDRESS:
2393 /* v4 addresses are not allowed on v6-only socket */
2394 if (ipv6_only_sock(asoc->base.sk))
2395 break;
2396 do_addr_param:
2397 af = sctp_get_af_specific(param_type2af(param.p->type));
2398 af->from_addr_param(&addr, param.addr, htons(asoc->peer.port), 0);
2399 scope = sctp_scope(peer_addr);
2400 if (sctp_in_scope(&addr, scope))
2401 if (!sctp_assoc_add_peer(asoc, &addr, gfp, SCTP_UNCONFIRMED))
2402 return 0;
2403 break;
2404
2405 case SCTP_PARAM_COOKIE_PRESERVATIVE:
2406 if (!sctp_cookie_preserve_enable)
2407 break;
2408
2409 stale = ntohl(param.life->lifespan_increment);
2410
2411 /* Suggested Cookie Life span increment's unit is msec,
2412 * (1/1000sec).
2413 */
2414 asoc->cookie_life.tv_sec += stale / 1000;
2415 asoc->cookie_life.tv_usec += (stale % 1000) * 1000;
2416 break;
2417
2418 case SCTP_PARAM_HOST_NAME_ADDRESS:
2419 SCTP_DEBUG_PRINTK("unimplemented SCTP_HOST_NAME_ADDRESS\n");
2420 break;
2421
2422 case SCTP_PARAM_SUPPORTED_ADDRESS_TYPES:
2423 /* Turn off the default values first so we'll know which
2424 * ones are really set by the peer.
2425 */
2426 asoc->peer.ipv4_address = 0;
2427 asoc->peer.ipv6_address = 0;
2428
2429 /* Assume that peer supports the address family
2430 * by which it sends a packet.
2431 */
2432 if (peer_addr->sa.sa_family == AF_INET6)
2433 asoc->peer.ipv6_address = 1;
2434 else if (peer_addr->sa.sa_family == AF_INET)
2435 asoc->peer.ipv4_address = 1;
2436
2437 /* Cycle through address types; avoid divide by 0. */
2438 sat = ntohs(param.p->length) - sizeof(sctp_paramhdr_t);
2439 if (sat)
2440 sat /= sizeof(__u16);
2441
2442 for (i = 0; i < sat; ++i) {
2443 switch (param.sat->types[i]) {
2444 case SCTP_PARAM_IPV4_ADDRESS:
2445 asoc->peer.ipv4_address = 1;
2446 break;
2447
2448 case SCTP_PARAM_IPV6_ADDRESS:
2449 if (PF_INET6 == asoc->base.sk->sk_family)
2450 asoc->peer.ipv6_address = 1;
2451 break;
2452
2453 case SCTP_PARAM_HOST_NAME_ADDRESS:
2454 asoc->peer.hostname_address = 1;
2455 break;
2456
2457 default: /* Just ignore anything else. */
2458 break;
2459 }
2460 }
2461 break;
2462
2463 case SCTP_PARAM_STATE_COOKIE:
2464 asoc->peer.cookie_len =
2465 ntohs(param.p->length) - sizeof(sctp_paramhdr_t);
2466 asoc->peer.cookie = param.cookie->body;
2467 break;
2468
2469 case SCTP_PARAM_HEARTBEAT_INFO:
2470 /* Would be odd to receive, but it causes no problems. */
2471 break;
2472
2473 case SCTP_PARAM_UNRECOGNIZED_PARAMETERS:
2474 /* Rejected during verify stage. */
2475 break;
2476
2477 case SCTP_PARAM_ECN_CAPABLE:
2478 asoc->peer.ecn_capable = 1;
2479 break;
2480
2481 case SCTP_PARAM_ADAPTATION_LAYER_IND:
2482 asoc->peer.adaptation_ind = ntohl(param.aind->adaptation_ind);
2483 break;
2484
2485 case SCTP_PARAM_SET_PRIMARY:
2486 if (!sctp_addip_enable)
2487 goto fall_through;
2488
2489 addr_param = param.v + sizeof(sctp_addip_param_t);
2490
2491 af = sctp_get_af_specific(param_type2af(param.p->type));
2492 af->from_addr_param(&addr, addr_param,
2493 htons(asoc->peer.port), 0);
2494
2495 /* if the address is invalid, we can't process it.
2496 * XXX: see spec for what to do.
2497 */
2498 if (!af->addr_valid(&addr, NULL, NULL))
2499 break;
2500
2501 t = sctp_assoc_lookup_paddr(asoc, &addr);
2502 if (!t)
2503 break;
2504
2505 sctp_assoc_set_primary(asoc, t);
2506 break;
2507
2508 case SCTP_PARAM_SUPPORTED_EXT:
2509 sctp_process_ext_param(asoc, param);
2510 break;
2511
2512 case SCTP_PARAM_FWD_TSN_SUPPORT:
2513 if (sctp_prsctp_enable) {
2514 asoc->peer.prsctp_capable = 1;
2515 break;
2516 }
2517 /* Fall Through */
2518 goto fall_through;
2519
2520 case SCTP_PARAM_RANDOM:
2521 if (!sctp_auth_enable)
2522 goto fall_through;
2523
2524 /* Save peer's random parameter */
2525 asoc->peer.peer_random = kmemdup(param.p,
2526 ntohs(param.p->length), gfp);
2527 if (!asoc->peer.peer_random) {
2528 retval = 0;
2529 break;
2530 }
2531 break;
2532
2533 case SCTP_PARAM_HMAC_ALGO:
2534 if (!sctp_auth_enable)
2535 goto fall_through;
2536
2537 /* Save peer's HMAC list */
2538 asoc->peer.peer_hmacs = kmemdup(param.p,
2539 ntohs(param.p->length), gfp);
2540 if (!asoc->peer.peer_hmacs) {
2541 retval = 0;
2542 break;
2543 }
2544
2545 /* Set the default HMAC the peer requested*/
2546 sctp_auth_asoc_set_default_hmac(asoc, param.hmac_algo);
2547 break;
2548
2549 case SCTP_PARAM_CHUNKS:
2550 if (!sctp_auth_enable)
2551 goto fall_through;
2552
2553 asoc->peer.peer_chunks = kmemdup(param.p,
2554 ntohs(param.p->length), gfp);
2555 if (!asoc->peer.peer_chunks)
2556 retval = 0;
2557 break;
2558 fall_through:
2559 default:
2560 /* Any unrecognized parameters should have been caught
2561 * and handled by sctp_verify_param() which should be
2562 * called prior to this routine. Simply log the error
2563 * here.
2564 */
2565 SCTP_DEBUG_PRINTK("Ignoring param: %d for association %p.\n",
2566 ntohs(param.p->type), asoc);
2567 break;
2568 }
2569
2570 return retval;
2571 }
2572
2573 /* Select a new verification tag. */
2574 __u32 sctp_generate_tag(const struct sctp_endpoint *ep)
2575 {
2576 /* I believe that this random number generator complies with RFC1750.
2577 * A tag of 0 is reserved for special cases (e.g. INIT).
2578 */
2579 __u32 x;
2580
2581 do {
2582 get_random_bytes(&x, sizeof(__u32));
2583 } while (x == 0);
2584
2585 return x;
2586 }
2587
2588 /* Select an initial TSN to send during startup. */
2589 __u32 sctp_generate_tsn(const struct sctp_endpoint *ep)
2590 {
2591 __u32 retval;
2592
2593 get_random_bytes(&retval, sizeof(__u32));
2594 return retval;
2595 }
2596
2597 /*
2598 * ADDIP 3.1.1 Address Configuration Change Chunk (ASCONF)
2599 * 0 1 2 3
2600 * 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
2601 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2602 * | Type = 0xC1 | Chunk Flags | Chunk Length |
2603 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2604 * | Serial Number |
2605 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2606 * | Address Parameter |
2607 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2608 * | ASCONF Parameter #1 |
2609 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2610 * \ \
2611 * / .... /
2612 * \ \
2613 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2614 * | ASCONF Parameter #N |
2615 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2616 *
2617 * Address Parameter and other parameter will not be wrapped in this function
2618 */
2619 static struct sctp_chunk *sctp_make_asconf(struct sctp_association *asoc,
2620 union sctp_addr *addr,
2621 int vparam_len)
2622 {
2623 sctp_addiphdr_t asconf;
2624 struct sctp_chunk *retval;
2625 int length = sizeof(asconf) + vparam_len;
2626 union sctp_addr_param addrparam;
2627 int addrlen;
2628 struct sctp_af *af = sctp_get_af_specific(addr->v4.sin_family);
2629
2630 addrlen = af->to_addr_param(addr, &addrparam);
2631 if (!addrlen)
2632 return NULL;
2633 length += addrlen;
2634
2635 /* Create the chunk. */
2636 retval = sctp_make_chunk(asoc, SCTP_CID_ASCONF, 0, length);
2637 if (!retval)
2638 return NULL;
2639
2640 asconf.serial = htonl(asoc->addip_serial++);
2641
2642 retval->subh.addip_hdr =
2643 sctp_addto_chunk(retval, sizeof(asconf), &asconf);
2644 retval->param_hdr.v =
2645 sctp_addto_chunk(retval, addrlen, &addrparam);
2646
2647 return retval;
2648 }
2649
2650 /* ADDIP
2651 * 3.2.1 Add IP Address
2652 * 0 1 2 3
2653 * 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
2654 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2655 * | Type = 0xC001 | Length = Variable |
2656 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2657 * | ASCONF-Request Correlation ID |
2658 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2659 * | Address Parameter |
2660 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2661 *
2662 * 3.2.2 Delete IP Address
2663 * 0 1 2 3
2664 * 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
2665 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2666 * | Type = 0xC002 | Length = Variable |
2667 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2668 * | ASCONF-Request Correlation ID |
2669 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2670 * | Address Parameter |
2671 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2672 *
2673 */
2674 struct sctp_chunk *sctp_make_asconf_update_ip(struct sctp_association *asoc,
2675 union sctp_addr *laddr,
2676 struct sockaddr *addrs,
2677 int addrcnt,
2678 __be16 flags)
2679 {
2680 sctp_addip_param_t param;
2681 struct sctp_chunk *retval;
2682 union sctp_addr_param addr_param;
2683 union sctp_addr *addr;
2684 void *addr_buf;
2685 struct sctp_af *af;
2686 int paramlen = sizeof(param);
2687 int addr_param_len = 0;
2688 int totallen = 0;
2689 int i;
2690
2691 /* Get total length of all the address parameters. */
2692 addr_buf = addrs;
2693 for (i = 0; i < addrcnt; i++) {
2694 addr = (union sctp_addr *)addr_buf;
2695 af = sctp_get_af_specific(addr->v4.sin_family);
2696 addr_param_len = af->to_addr_param(addr, &addr_param);
2697
2698 totallen += paramlen;
2699 totallen += addr_param_len;
2700
2701 addr_buf += af->sockaddr_len;
2702 }
2703
2704 /* Create an asconf chunk with the required length. */
2705 retval = sctp_make_asconf(asoc, laddr, totallen);
2706 if (!retval)
2707 return NULL;
2708
2709 /* Add the address parameters to the asconf chunk. */
2710 addr_buf = addrs;
2711 for (i = 0; i < addrcnt; i++) {
2712 addr = (union sctp_addr *)addr_buf;
2713 af = sctp_get_af_specific(addr->v4.sin_family);
2714 addr_param_len = af->to_addr_param(addr, &addr_param);
2715 param.param_hdr.type = flags;
2716 param.param_hdr.length = htons(paramlen + addr_param_len);
2717 param.crr_id = i;
2718
2719 sctp_addto_chunk(retval, paramlen, &param);
2720 sctp_addto_chunk(retval, addr_param_len, &addr_param);
2721
2722 addr_buf += af->sockaddr_len;
2723 }
2724 return retval;
2725 }
2726
2727 /* ADDIP
2728 * 3.2.4 Set Primary IP Address
2729 * 0 1 2 3
2730 * 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
2731 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2732 * | Type =0xC004 | Length = Variable |
2733 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2734 * | ASCONF-Request Correlation ID |
2735 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2736 * | Address Parameter |
2737 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2738 *
2739 * Create an ASCONF chunk with Set Primary IP address parameter.
2740 */
2741 struct sctp_chunk *sctp_make_asconf_set_prim(struct sctp_association *asoc,
2742 union sctp_addr *addr)
2743 {
2744 sctp_addip_param_t param;
2745 struct sctp_chunk *retval;
2746 int len = sizeof(param);
2747 union sctp_addr_param addrparam;
2748 int addrlen;
2749 struct sctp_af *af = sctp_get_af_specific(addr->v4.sin_family);
2750
2751 addrlen = af->to_addr_param(addr, &addrparam);
2752 if (!addrlen)
2753 return NULL;
2754 len += addrlen;
2755
2756 /* Create the chunk and make asconf header. */
2757 retval = sctp_make_asconf(asoc, addr, len);
2758 if (!retval)
2759 return NULL;
2760
2761 param.param_hdr.type = SCTP_PARAM_SET_PRIMARY;
2762 param.param_hdr.length = htons(len);
2763 param.crr_id = 0;
2764
2765 sctp_addto_chunk(retval, sizeof(param), &param);
2766 sctp_addto_chunk(retval, addrlen, &addrparam);
2767
2768 return retval;
2769 }
2770
2771 /* ADDIP 3.1.2 Address Configuration Acknowledgement Chunk (ASCONF-ACK)
2772 * 0 1 2 3
2773 * 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
2774 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2775 * | Type = 0x80 | Chunk Flags | Chunk Length |
2776 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2777 * | Serial Number |
2778 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2779 * | ASCONF Parameter Response#1 |
2780 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2781 * \ \
2782 * / .... /
2783 * \ \
2784 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2785 * | ASCONF Parameter Response#N |
2786 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2787 *
2788 * Create an ASCONF_ACK chunk with enough space for the parameter responses.
2789 */
2790 static struct sctp_chunk *sctp_make_asconf_ack(const struct sctp_association *asoc,
2791 __u32 serial, int vparam_len)
2792 {
2793 sctp_addiphdr_t asconf;
2794 struct sctp_chunk *retval;
2795 int length = sizeof(asconf) + vparam_len;
2796
2797 /* Create the chunk. */
2798 retval = sctp_make_chunk(asoc, SCTP_CID_ASCONF_ACK, 0, length);
2799 if (!retval)
2800 return NULL;
2801
2802 asconf.serial = htonl(serial);
2803
2804 retval->subh.addip_hdr =
2805 sctp_addto_chunk(retval, sizeof(asconf), &asconf);
2806
2807 return retval;
2808 }
2809
2810 /* Add response parameters to an ASCONF_ACK chunk. */
2811 static void sctp_add_asconf_response(struct sctp_chunk *chunk, __be32 crr_id,
2812 __be16 err_code, sctp_addip_param_t *asconf_param)
2813 {
2814 sctp_addip_param_t ack_param;
2815 sctp_errhdr_t err_param;
2816 int asconf_param_len = 0;
2817 int err_param_len = 0;
2818 __be16 response_type;
2819
2820 if (SCTP_ERROR_NO_ERROR == err_code) {
2821 response_type = SCTP_PARAM_SUCCESS_REPORT;
2822 } else {
2823 response_type = SCTP_PARAM_ERR_CAUSE;
2824 err_param_len = sizeof(err_param);
2825 if (asconf_param)
2826 asconf_param_len =
2827 ntohs(asconf_param->param_hdr.length);
2828 }
2829
2830 /* Add Success Indication or Error Cause Indication parameter. */
2831 ack_param.param_hdr.type = response_type;
2832 ack_param.param_hdr.length = htons(sizeof(ack_param) +
2833 err_param_len +
2834 asconf_param_len);
2835 ack_param.crr_id = crr_id;
2836 sctp_addto_chunk(chunk, sizeof(ack_param), &ack_param);
2837
2838 if (SCTP_ERROR_NO_ERROR == err_code)
2839 return;
2840
2841 /* Add Error Cause parameter. */
2842 err_param.cause = err_code;
2843 err_param.length = htons(err_param_len + asconf_param_len);
2844 sctp_addto_chunk(chunk, err_param_len, &err_param);
2845
2846 /* Add the failed TLV copied from ASCONF chunk. */
2847 if (asconf_param)
2848 sctp_addto_chunk(chunk, asconf_param_len, asconf_param);
2849 }
2850
2851 /* Process a asconf parameter. */
2852 static __be16 sctp_process_asconf_param(struct sctp_association *asoc,
2853 struct sctp_chunk *asconf,
2854 sctp_addip_param_t *asconf_param)
2855 {
2856 struct sctp_transport *peer;
2857 struct sctp_af *af;
2858 union sctp_addr addr;
2859 union sctp_addr_param *addr_param;
2860
2861 addr_param = (union sctp_addr_param *)
2862 ((void *)asconf_param + sizeof(sctp_addip_param_t));
2863
2864 switch (addr_param->v4.param_hdr.type) {
2865 case SCTP_PARAM_IPV6_ADDRESS:
2866 if (!asoc->peer.ipv6_address)
2867 return SCTP_ERROR_INV_PARAM;
2868 break;
2869 case SCTP_PARAM_IPV4_ADDRESS:
2870 if (!asoc->peer.ipv4_address)
2871 return SCTP_ERROR_INV_PARAM;
2872 break;
2873 default:
2874 return SCTP_ERROR_INV_PARAM;
2875 }
2876
2877 af = sctp_get_af_specific(param_type2af(addr_param->v4.param_hdr.type));
2878 if (unlikely(!af))
2879 return SCTP_ERROR_INV_PARAM;
2880
2881 af->from_addr_param(&addr, addr_param, htons(asoc->peer.port), 0);
2882
2883 /* ADDIP 4.2.1 This parameter MUST NOT contain a broadcast
2884 * or multicast address.
2885 * (note: wildcard is permitted and requires special handling so
2886 * make sure we check for that)
2887 */
2888 if (!af->is_any(&addr) && !af->addr_valid(&addr, NULL, asconf->skb))
2889 return SCTP_ERROR_INV_PARAM;
2890
2891 switch (asconf_param->param_hdr.type) {
2892 case SCTP_PARAM_ADD_IP:
2893 /* Section 4.2.1:
2894 * If the address 0.0.0.0 or ::0 is provided, the source
2895 * address of the packet MUST be added.
2896 */
2897 if (af->is_any(&addr))
2898 memcpy(&addr, &asconf->source, sizeof(addr));
2899
2900 /* ADDIP 4.3 D9) If an endpoint receives an ADD IP address
2901 * request and does not have the local resources to add this
2902 * new address to the association, it MUST return an Error
2903 * Cause TLV set to the new error code 'Operation Refused
2904 * Due to Resource Shortage'.
2905 */
2906
2907 peer = sctp_assoc_add_peer(asoc, &addr, GFP_ATOMIC, SCTP_UNCONFIRMED);
2908 if (!peer)
2909 return SCTP_ERROR_RSRC_LOW;
2910
2911 /* Start the heartbeat timer. */
2912 if (!mod_timer(&peer->hb_timer, sctp_transport_timeout(peer)))
2913 sctp_transport_hold(peer);
2914 break;
2915 case SCTP_PARAM_DEL_IP:
2916 /* ADDIP 4.3 D7) If a request is received to delete the
2917 * last remaining IP address of a peer endpoint, the receiver
2918 * MUST send an Error Cause TLV with the error cause set to the
2919 * new error code 'Request to Delete Last Remaining IP Address'.
2920 */
2921 if (asoc->peer.transport_count == 1)
2922 return SCTP_ERROR_DEL_LAST_IP;
2923
2924 /* ADDIP 4.3 D8) If a request is received to delete an IP
2925 * address which is also the source address of the IP packet
2926 * which contained the ASCONF chunk, the receiver MUST reject
2927 * this request. To reject the request the receiver MUST send
2928 * an Error Cause TLV set to the new error code 'Request to
2929 * Delete Source IP Address'
2930 */
2931 if (sctp_cmp_addr_exact(sctp_source(asconf), &addr))
2932 return SCTP_ERROR_DEL_SRC_IP;
2933
2934 /* Section 4.2.2
2935 * If the address 0.0.0.0 or ::0 is provided, all
2936 * addresses of the peer except the source address of the
2937 * packet MUST be deleted.
2938 */
2939 if (af->is_any(&addr)) {
2940 sctp_assoc_set_primary(asoc, asconf->transport);
2941 sctp_assoc_del_nonprimary_peers(asoc,
2942 asconf->transport);
2943 } else
2944 sctp_assoc_del_peer(asoc, &addr);
2945 break;
2946 case SCTP_PARAM_SET_PRIMARY:
2947 /* ADDIP Section 4.2.4
2948 * If the address 0.0.0.0 or ::0 is provided, the receiver
2949 * MAY mark the source address of the packet as its
2950 * primary.
2951 */
2952 if (af->is_any(&addr))
2953 memcpy(&addr.v4, sctp_source(asconf), sizeof(addr));
2954
2955 peer = sctp_assoc_lookup_paddr(asoc, &addr);
2956 if (!peer)
2957 return SCTP_ERROR_INV_PARAM;
2958
2959 sctp_assoc_set_primary(asoc, peer);
2960 break;
2961 default:
2962 return SCTP_ERROR_INV_PARAM;
2963 break;
2964 }
2965
2966 return SCTP_ERROR_NO_ERROR;
2967 }
2968
2969 /* Verify the ASCONF packet before we process it. */
2970 int sctp_verify_asconf(const struct sctp_association *asoc,
2971 struct sctp_paramhdr *param_hdr, void *chunk_end,
2972 struct sctp_paramhdr **errp) {
2973 sctp_addip_param_t *asconf_param;
2974 union sctp_params param;
2975 int length, plen;
2976
2977 param.v = (sctp_paramhdr_t *) param_hdr;
2978 while (param.v <= chunk_end - sizeof(sctp_paramhdr_t)) {
2979 length = ntohs(param.p->length);
2980 *errp = param.p;
2981
2982 if (param.v > chunk_end - length ||
2983 length < sizeof(sctp_paramhdr_t))
2984 return 0;
2985
2986 switch (param.p->type) {
2987 case SCTP_PARAM_ADD_IP:
2988 case SCTP_PARAM_DEL_IP:
2989 case SCTP_PARAM_SET_PRIMARY:
2990 asconf_param = (sctp_addip_param_t *)param.v;
2991 plen = ntohs(asconf_param->param_hdr.length);
2992 if (plen < sizeof(sctp_addip_param_t) +
2993 sizeof(sctp_paramhdr_t))
2994 return 0;
2995 break;
2996 case SCTP_PARAM_SUCCESS_REPORT:
2997 case SCTP_PARAM_ADAPTATION_LAYER_IND:
2998 if (length != sizeof(sctp_addip_param_t))
2999 return 0;
3000
3001 break;
3002 default:
3003 break;
3004 }
3005
3006 param.v += WORD_ROUND(length);
3007 }
3008
3009 if (param.v != chunk_end)
3010 return 0;
3011
3012 return 1;
3013 }
3014
3015 /* Process an incoming ASCONF chunk with the next expected serial no. and
3016 * return an ASCONF_ACK chunk to be sent in response.
3017 */
3018 struct sctp_chunk *sctp_process_asconf(struct sctp_association *asoc,
3019 struct sctp_chunk *asconf)
3020 {
3021 sctp_addiphdr_t *hdr;
3022 union sctp_addr_param *addr_param;
3023 sctp_addip_param_t *asconf_param;
3024 struct sctp_chunk *asconf_ack;
3025
3026 __be16 err_code;
3027 int length = 0;
3028 int chunk_len;
3029 __u32 serial;
3030 int all_param_pass = 1;
3031
3032 chunk_len = ntohs(asconf->chunk_hdr->length) - sizeof(sctp_chunkhdr_t);
3033 hdr = (sctp_addiphdr_t *)asconf->skb->data;
3034 serial = ntohl(hdr->serial);
3035
3036 /* Skip the addiphdr and store a pointer to address parameter. */
3037 length = sizeof(sctp_addiphdr_t);
3038 addr_param = (union sctp_addr_param *)(asconf->skb->data + length);
3039 chunk_len -= length;
3040
3041 /* Skip the address parameter and store a pointer to the first
3042 * asconf parameter.
3043 */
3044 length = ntohs(addr_param->v4.param_hdr.length);
3045 asconf_param = (sctp_addip_param_t *)((void *)addr_param + length);
3046 chunk_len -= length;
3047
3048 /* create an ASCONF_ACK chunk.
3049 * Based on the definitions of parameters, we know that the size of
3050 * ASCONF_ACK parameters are less than or equal to the twice of ASCONF
3051 * parameters.
3052 */
3053 asconf_ack = sctp_make_asconf_ack(asoc, serial, chunk_len * 2);
3054 if (!asconf_ack)
3055 goto done;
3056
3057 /* Process the TLVs contained within the ASCONF chunk. */
3058 while (chunk_len > 0) {
3059 err_code = sctp_process_asconf_param(asoc, asconf,
3060 asconf_param);
3061 /* ADDIP 4.1 A7)
3062 * If an error response is received for a TLV parameter,
3063 * all TLVs with no response before the failed TLV are
3064 * considered successful if not reported. All TLVs after
3065 * the failed response are considered unsuccessful unless
3066 * a specific success indication is present for the parameter.
3067 */
3068 if (SCTP_ERROR_NO_ERROR != err_code)
3069 all_param_pass = 0;
3070
3071 if (!all_param_pass)
3072 sctp_add_asconf_response(asconf_ack,
3073 asconf_param->crr_id, err_code,
3074 asconf_param);
3075
3076 /* ADDIP 4.3 D11) When an endpoint receiving an ASCONF to add
3077 * an IP address sends an 'Out of Resource' in its response, it
3078 * MUST also fail any subsequent add or delete requests bundled
3079 * in the ASCONF.
3080 */
3081 if (SCTP_ERROR_RSRC_LOW == err_code)
3082 goto done;
3083
3084 /* Move to the next ASCONF param. */
3085 length = ntohs(asconf_param->param_hdr.length);
3086 asconf_param = (sctp_addip_param_t *)((void *)asconf_param +
3087 length);
3088 chunk_len -= length;
3089 }
3090
3091 done:
3092 asoc->peer.addip_serial++;
3093
3094 /* If we are sending a new ASCONF_ACK hold a reference to it in assoc
3095 * after freeing the reference to old asconf ack if any.
3096 */
3097 if (asconf_ack) {
3098 sctp_chunk_hold(asconf_ack);
3099 list_add_tail(&asconf_ack->transmitted_list,
3100 &asoc->asconf_ack_list);
3101 }
3102
3103 return asconf_ack;
3104 }
3105
3106 /* Process a asconf parameter that is successfully acked. */
3107 static int sctp_asconf_param_success(struct sctp_association *asoc,
3108 sctp_addip_param_t *asconf_param)
3109 {
3110 struct sctp_af *af;
3111 union sctp_addr addr;
3112 struct sctp_bind_addr *bp = &asoc->base.bind_addr;
3113 union sctp_addr_param *addr_param;
3114 struct sctp_transport *transport;
3115 struct sctp_sockaddr_entry *saddr;
3116 int retval = 0;
3117
3118 addr_param = (union sctp_addr_param *)
3119 ((void *)asconf_param + sizeof(sctp_addip_param_t));
3120
3121 /* We have checked the packet before, so we do not check again. */
3122 af = sctp_get_af_specific(param_type2af(addr_param->v4.param_hdr.type));
3123 af->from_addr_param(&addr, addr_param, htons(bp->port), 0);
3124
3125 switch (asconf_param->param_hdr.type) {
3126 case SCTP_PARAM_ADD_IP:
3127 /* This is always done in BH context with a socket lock
3128 * held, so the list can not change.
3129 */
3130 local_bh_disable();
3131 list_for_each_entry(saddr, &bp->address_list, list) {
3132 if (sctp_cmp_addr_exact(&saddr->a, &addr))
3133 saddr->state = SCTP_ADDR_SRC;
3134 }
3135 local_bh_enable();
3136 break;
3137 case SCTP_PARAM_DEL_IP:
3138 local_bh_disable();
3139 retval = sctp_del_bind_addr(bp, &addr);
3140 local_bh_enable();
3141 list_for_each_entry(transport, &asoc->peer.transport_addr_list,
3142 transports) {
3143 dst_release(transport->dst);
3144 sctp_transport_route(transport, NULL,
3145 sctp_sk(asoc->base.sk));
3146 }
3147 break;
3148 default:
3149 break;
3150 }
3151
3152 return retval;
3153 }
3154
3155 /* Get the corresponding ASCONF response error code from the ASCONF_ACK chunk
3156 * for the given asconf parameter. If there is no response for this parameter,
3157 * return the error code based on the third argument 'no_err'.
3158 * ADDIP 4.1
3159 * A7) If an error response is received for a TLV parameter, all TLVs with no
3160 * response before the failed TLV are considered successful if not reported.
3161 * All TLVs after the failed response are considered unsuccessful unless a
3162 * specific success indication is present for the parameter.
3163 */
3164 static __be16 sctp_get_asconf_response(struct sctp_chunk *asconf_ack,
3165 sctp_addip_param_t *asconf_param,
3166 int no_err)
3167 {
3168 sctp_addip_param_t *asconf_ack_param;
3169 sctp_errhdr_t *err_param;
3170 int length;
3171 int asconf_ack_len;
3172 __be16 err_code;
3173
3174 if (no_err)
3175 err_code = SCTP_ERROR_NO_ERROR;
3176 else
3177 err_code = SCTP_ERROR_REQ_REFUSED;
3178
3179 asconf_ack_len = ntohs(asconf_ack->chunk_hdr->length) -
3180 sizeof(sctp_chunkhdr_t);
3181
3182 /* Skip the addiphdr from the asconf_ack chunk and store a pointer to
3183 * the first asconf_ack parameter.
3184 */
3185 length = sizeof(sctp_addiphdr_t);
3186 asconf_ack_param = (sctp_addip_param_t *)(asconf_ack->skb->data +
3187 length);
3188 asconf_ack_len -= length;
3189
3190 while (asconf_ack_len > 0) {
3191 if (asconf_ack_param->crr_id == asconf_param->crr_id) {
3192 switch(asconf_ack_param->param_hdr.type) {
3193 case SCTP_PARAM_SUCCESS_REPORT:
3194 return SCTP_ERROR_NO_ERROR;
3195 case SCTP_PARAM_ERR_CAUSE:
3196 length = sizeof(sctp_addip_param_t);
3197 err_param = (sctp_errhdr_t *)
3198 ((void *)asconf_ack_param + length);
3199 asconf_ack_len -= length;
3200 if (asconf_ack_len > 0)
3201 return err_param->cause;
3202 else
3203 return SCTP_ERROR_INV_PARAM;
3204 break;
3205 default:
3206 return SCTP_ERROR_INV_PARAM;
3207 }
3208 }
3209
3210 length = ntohs(asconf_ack_param->param_hdr.length);
3211 asconf_ack_param = (sctp_addip_param_t *)
3212 ((void *)asconf_ack_param + length);
3213 asconf_ack_len -= length;
3214 }
3215
3216 return err_code;
3217 }
3218
3219 /* Process an incoming ASCONF_ACK chunk against the cached last ASCONF chunk. */
3220 int sctp_process_asconf_ack(struct sctp_association *asoc,
3221 struct sctp_chunk *asconf_ack)
3222 {
3223 struct sctp_chunk *asconf = asoc->addip_last_asconf;
3224 union sctp_addr_param *addr_param;
3225 sctp_addip_param_t *asconf_param;
3226 int length = 0;
3227 int asconf_len = asconf->skb->len;
3228 int all_param_pass = 0;
3229 int no_err = 1;
3230 int retval = 0;
3231 __be16 err_code = SCTP_ERROR_NO_ERROR;
3232
3233 /* Skip the chunkhdr and addiphdr from the last asconf sent and store
3234 * a pointer to address parameter.
3235 */
3236 length = sizeof(sctp_addip_chunk_t);
3237 addr_param = (union sctp_addr_param *)(asconf->skb->data + length);
3238 asconf_len -= length;
3239
3240 /* Skip the address parameter in the last asconf sent and store a
3241 * pointer to the first asconf parameter.
3242 */
3243 length = ntohs(addr_param->v4.param_hdr.length);
3244 asconf_param = (sctp_addip_param_t *)((void *)addr_param + length);
3245 asconf_len -= length;
3246
3247 /* ADDIP 4.1
3248 * A8) If there is no response(s) to specific TLV parameter(s), and no
3249 * failures are indicated, then all request(s) are considered
3250 * successful.
3251 */
3252 if (asconf_ack->skb->len == sizeof(sctp_addiphdr_t))
3253 all_param_pass = 1;
3254
3255 /* Process the TLVs contained in the last sent ASCONF chunk. */
3256 while (asconf_len > 0) {
3257 if (all_param_pass)
3258 err_code = SCTP_ERROR_NO_ERROR;
3259 else {
3260 err_code = sctp_get_asconf_response(asconf_ack,
3261 asconf_param,
3262 no_err);
3263 if (no_err && (SCTP_ERROR_NO_ERROR != err_code))
3264 no_err = 0;
3265 }
3266
3267 switch (err_code) {
3268 case SCTP_ERROR_NO_ERROR:
3269 retval = sctp_asconf_param_success(asoc, asconf_param);
3270 break;
3271
3272 case SCTP_ERROR_RSRC_LOW:
3273 retval = 1;
3274 break;
3275
3276 case SCTP_ERROR_INV_PARAM:
3277 /* Disable sending this type of asconf parameter in
3278 * future.
3279 */
3280 asoc->peer.addip_disabled_mask |=
3281 asconf_param->param_hdr.type;
3282 break;
3283
3284 case SCTP_ERROR_REQ_REFUSED:
3285 case SCTP_ERROR_DEL_LAST_IP:
3286 case SCTP_ERROR_DEL_SRC_IP:
3287 default:
3288 break;
3289 }
3290
3291 /* Skip the processed asconf parameter and move to the next
3292 * one.
3293 */
3294 length = ntohs(asconf_param->param_hdr.length);
3295 asconf_param = (sctp_addip_param_t *)((void *)asconf_param +
3296 length);
3297 asconf_len -= length;
3298 }
3299
3300 /* Free the cached last sent asconf chunk. */
3301 list_del_init(&asconf->transmitted_list);
3302 sctp_chunk_free(asconf);
3303 asoc->addip_last_asconf = NULL;
3304
3305 /* Send the next asconf chunk from the addip chunk queue. */
3306 if (!list_empty(&asoc->addip_chunk_list)) {
3307 struct list_head *entry = asoc->addip_chunk_list.next;
3308 asconf = list_entry(entry, struct sctp_chunk, list);
3309
3310 list_del_init(entry);
3311
3312 /* Hold the chunk until an ASCONF_ACK is received. */
3313 sctp_chunk_hold(asconf);
3314 if (sctp_primitive_ASCONF(asoc, asconf))
3315 sctp_chunk_free(asconf);
3316 else
3317 asoc->addip_last_asconf = asconf;
3318 }
3319
3320 return retval;
3321 }
3322
3323 /* Make a FWD TSN chunk. */
3324 struct sctp_chunk *sctp_make_fwdtsn(const struct sctp_association *asoc,
3325 __u32 new_cum_tsn, size_t nstreams,
3326 struct sctp_fwdtsn_skip *skiplist)
3327 {
3328 struct sctp_chunk *retval = NULL;
3329 struct sctp_fwdtsn_chunk *ftsn_chunk;
3330 struct sctp_fwdtsn_hdr ftsn_hdr;
3331 struct sctp_fwdtsn_skip skip;
3332 size_t hint;
3333 int i;
3334
3335 hint = (nstreams + 1) * sizeof(__u32);
3336
3337 retval = sctp_make_chunk(asoc, SCTP_CID_FWD_TSN, 0, hint);
3338
3339 if (!retval)
3340 return NULL;
3341
3342 ftsn_chunk = (struct sctp_fwdtsn_chunk *)retval->subh.fwdtsn_hdr;
3343
3344 ftsn_hdr.new_cum_tsn = htonl(new_cum_tsn);
3345 retval->subh.fwdtsn_hdr =
3346 sctp_addto_chunk(retval, sizeof(ftsn_hdr), &ftsn_hdr);
3347
3348 for (i = 0; i < nstreams; i++) {
3349 skip.stream = skiplist[i].stream;
3350 skip.ssn = skiplist[i].ssn;
3351 sctp_addto_chunk(retval, sizeof(skip), &skip);
3352 }
3353
3354 return retval;
3355 }
Support for the Chinese Samsung S3C2440 based development boards