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Linus Torvalds1da177e2005-04-16 15:20:36 -07001/* SCTP kernel reference Implementation
2 * (C) Copyright IBM Corp. 2001, 2004
3 * Copyright (c) 1999-2000 Cisco, Inc.
4 * Copyright (c) 1999-2001 Motorola, Inc.
5 * Copyright (c) 2001-2002 Intel Corp.
6 *
7 * This file is part of the SCTP kernel reference Implementation
8 *
9 * These functions work with the state functions in sctp_sm_statefuns.c
10 * to implement the state operations. These functions implement the
11 * steps which require modifying existing data structures.
12 *
13 * The SCTP reference implementation is free software;
14 * you can redistribute it and/or modify it under the terms of
15 * the GNU General Public License as published by
16 * the Free Software Foundation; either version 2, or (at your option)
17 * any later version.
18 *
19 * The SCTP reference implementation is distributed in the hope that it
20 * will be useful, but WITHOUT ANY WARRANTY; without even the implied
21 * ************************
22 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
23 * See the GNU General Public License for more details.
24 *
25 * You should have received a copy of the GNU General Public License
26 * along with GNU CC; see the file COPYING. If not, write to
27 * the Free Software Foundation, 59 Temple Place - Suite 330,
28 * Boston, MA 02111-1307, USA.
29 *
30 * Please send any bug reports or fixes you make to the
31 * email address(es):
32 * lksctp developers <lksctp-developers@lists.sourceforge.net>
33 *
34 * Or submit a bug report through the following website:
35 * http://www.sf.net/projects/lksctp
36 *
37 * Written or modified by:
38 * La Monte H.P. Yarroll <piggy@acm.org>
39 * Karl Knutson <karl@athena.chicago.il.us>
40 * C. Robin <chris@hundredacre.ac.uk>
41 * Jon Grimm <jgrimm@us.ibm.com>
42 * Xingang Guo <xingang.guo@intel.com>
43 * Dajiang Zhang <dajiang.zhang@nokia.com>
44 * Sridhar Samudrala <sri@us.ibm.com>
45 * Daisy Chang <daisyc@us.ibm.com>
46 * Ardelle Fan <ardelle.fan@intel.com>
47 * Kevin Gao <kevin.gao@intel.com>
48 *
49 * Any bugs reported given to us we will try to fix... any fixes shared will
50 * be incorporated into the next SCTP release.
51 */
52
53#include <linux/types.h>
54#include <linux/kernel.h>
55#include <linux/ip.h>
56#include <linux/ipv6.h>
57#include <linux/net.h>
58#include <linux/inet.h>
59#include <asm/scatterlist.h>
60#include <linux/crypto.h>
61#include <net/sock.h>
62
63#include <linux/skbuff.h>
64#include <linux/random.h> /* for get_random_bytes */
65#include <net/sctp/sctp.h>
66#include <net/sctp/sm.h>
67
68extern kmem_cache_t *sctp_chunk_cachep;
69
70SCTP_STATIC
71struct sctp_chunk *sctp_make_chunk(const struct sctp_association *asoc,
72 __u8 type, __u8 flags, int paylen);
73static sctp_cookie_param_t *sctp_pack_cookie(const struct sctp_endpoint *ep,
74 const struct sctp_association *asoc,
75 const struct sctp_chunk *init_chunk,
76 int *cookie_len,
77 const __u8 *raw_addrs, int addrs_len);
78static int sctp_process_param(struct sctp_association *asoc,
79 union sctp_params param,
80 const union sctp_addr *peer_addr,
Al Virodd0fc662005-10-07 07:46:04 +010081 gfp_t gfp);
Linus Torvalds1da177e2005-04-16 15:20:36 -070082
83/* What was the inbound interface for this chunk? */
84int sctp_chunk_iif(const struct sctp_chunk *chunk)
85{
86 struct sctp_af *af;
87 int iif = 0;
88
89 af = sctp_get_af_specific(ipver2af(chunk->skb->nh.iph->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 */
101static const struct sctp_paramhdr ecap_param = {
102 SCTP_PARAM_ECN_CAPABLE,
103 __constant_htons(sizeof(struct sctp_paramhdr)),
104};
105static const struct sctp_paramhdr prsctp_param = {
106 SCTP_PARAM_FWD_TSN_SUPPORT,
107 __constant_htons(sizeof(struct sctp_paramhdr)),
108};
109
110/* A helper to initialize to initialize an op error inside a
111 * provided chunk, as most cause codes will be embedded inside an
112 * abort chunk.
113 */
114void sctp_init_cause(struct sctp_chunk *chunk, __u16 cause_code,
115 const void *payload, size_t paylen)
116{
117 sctp_errhdr_t err;
118 int padlen;
119 __u16 len;
120
121 /* Cause code constants are now defined in network order. */
122 err.cause = cause_code;
123 len = sizeof(sctp_errhdr_t) + paylen;
124 padlen = len % 4;
125 err.length = htons(len);
126 len += padlen;
127 sctp_addto_chunk(chunk, sizeof(sctp_errhdr_t), &err);
128 chunk->subh.err_hdr = sctp_addto_chunk(chunk, paylen, payload);
129}
130
131/* 3.3.2 Initiation (INIT) (1)
132 *
133 * This chunk is used to initiate a SCTP association between two
134 * endpoints. The format of the INIT chunk is shown below:
135 *
136 * 0 1 2 3
137 * 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
138 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
139 * | Type = 1 | Chunk Flags | Chunk Length |
140 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
141 * | Initiate Tag |
142 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
143 * | Advertised Receiver Window Credit (a_rwnd) |
144 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
145 * | Number of Outbound Streams | Number of Inbound Streams |
146 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
147 * | Initial TSN |
148 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
149 * \ \
150 * / Optional/Variable-Length Parameters /
151 * \ \
152 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
153 *
154 *
155 * The INIT chunk contains the following parameters. Unless otherwise
156 * noted, each parameter MUST only be included once in the INIT chunk.
157 *
158 * Fixed Parameters Status
159 * ----------------------------------------------
160 * Initiate Tag Mandatory
161 * Advertised Receiver Window Credit Mandatory
162 * Number of Outbound Streams Mandatory
163 * Number of Inbound Streams Mandatory
164 * Initial TSN Mandatory
165 *
166 * Variable Parameters Status Type Value
167 * -------------------------------------------------------------
168 * IPv4 Address (Note 1) Optional 5
169 * IPv6 Address (Note 1) Optional 6
170 * Cookie Preservative Optional 9
171 * Reserved for ECN Capable (Note 2) Optional 32768 (0x8000)
172 * Host Name Address (Note 3) Optional 11
173 * Supported Address Types (Note 4) Optional 12
174 */
175struct sctp_chunk *sctp_make_init(const struct sctp_association *asoc,
176 const struct sctp_bind_addr *bp,
Al Virodd0fc662005-10-07 07:46:04 +0100177 gfp_t gfp, int vparam_len)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700178{
179 sctp_inithdr_t init;
180 union sctp_params addrs;
181 size_t chunksize;
182 struct sctp_chunk *retval = NULL;
183 int num_types, addrs_len = 0;
184 struct sctp_sock *sp;
185 sctp_supported_addrs_param_t sat;
186 __u16 types[2];
187 sctp_adaption_ind_param_t aiparam;
188
189 /* RFC 2960 3.3.2 Initiation (INIT) (1)
190 *
191 * Note 1: The INIT chunks can contain multiple addresses that
192 * can be IPv4 and/or IPv6 in any combination.
193 */
194 retval = NULL;
195
196 /* Convert the provided bind address list to raw format. */
197 addrs = sctp_bind_addrs_to_raw(bp, &addrs_len, gfp);
198
199 init.init_tag = htonl(asoc->c.my_vtag);
200 init.a_rwnd = htonl(asoc->rwnd);
201 init.num_outbound_streams = htons(asoc->c.sinit_num_ostreams);
202 init.num_inbound_streams = htons(asoc->c.sinit_max_instreams);
203 init.initial_tsn = htonl(asoc->c.initial_tsn);
204
205 /* How many address types are needed? */
206 sp = sctp_sk(asoc->base.sk);
207 num_types = sp->pf->supported_addrs(sp, types);
208
209 chunksize = sizeof(init) + addrs_len + SCTP_SAT_LEN(num_types);
210 chunksize += sizeof(ecap_param);
211 if (sctp_prsctp_enable)
212 chunksize += sizeof(prsctp_param);
213 chunksize += sizeof(aiparam);
214 chunksize += vparam_len;
215
216 /* RFC 2960 3.3.2 Initiation (INIT) (1)
217 *
218 * Note 3: An INIT chunk MUST NOT contain more than one Host
219 * Name address parameter. Moreover, the sender of the INIT
220 * MUST NOT combine any other address types with the Host Name
221 * address in the INIT. The receiver of INIT MUST ignore any
222 * other address types if the Host Name address parameter is
223 * present in the received INIT chunk.
224 *
225 * PLEASE DO NOT FIXME [This version does not support Host Name.]
226 */
227
228 retval = sctp_make_chunk(asoc, SCTP_CID_INIT, 0, chunksize);
229 if (!retval)
230 goto nodata;
231
232 retval->subh.init_hdr =
233 sctp_addto_chunk(retval, sizeof(init), &init);
234 retval->param_hdr.v =
235 sctp_addto_chunk(retval, addrs_len, addrs.v);
236
237 /* RFC 2960 3.3.2 Initiation (INIT) (1)
238 *
239 * Note 4: This parameter, when present, specifies all the
240 * address types the sending endpoint can support. The absence
241 * of this parameter indicates that the sending endpoint can
242 * support any address type.
243 */
244 sat.param_hdr.type = SCTP_PARAM_SUPPORTED_ADDRESS_TYPES;
245 sat.param_hdr.length = htons(SCTP_SAT_LEN(num_types));
246 sctp_addto_chunk(retval, sizeof(sat), &sat);
247 sctp_addto_chunk(retval, num_types * sizeof(__u16), &types);
248
249 sctp_addto_chunk(retval, sizeof(ecap_param), &ecap_param);
250 if (sctp_prsctp_enable)
251 sctp_addto_chunk(retval, sizeof(prsctp_param), &prsctp_param);
252 aiparam.param_hdr.type = SCTP_PARAM_ADAPTION_LAYER_IND;
253 aiparam.param_hdr.length = htons(sizeof(aiparam));
254 aiparam.adaption_ind = htonl(sp->adaption_ind);
255 sctp_addto_chunk(retval, sizeof(aiparam), &aiparam);
256nodata:
Jesper Juhla51482b2005-11-08 09:41:34 -0800257 kfree(addrs.v);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700258 return retval;
259}
260
261struct sctp_chunk *sctp_make_init_ack(const struct sctp_association *asoc,
262 const struct sctp_chunk *chunk,
Al Virodd0fc662005-10-07 07:46:04 +0100263 gfp_t gfp, int unkparam_len)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700264{
265 sctp_inithdr_t initack;
266 struct sctp_chunk *retval;
267 union sctp_params addrs;
268 int addrs_len;
269 sctp_cookie_param_t *cookie;
270 int cookie_len;
271 size_t chunksize;
272 sctp_adaption_ind_param_t aiparam;
273
274 retval = NULL;
275
276 /* Note: there may be no addresses to embed. */
277 addrs = sctp_bind_addrs_to_raw(&asoc->base.bind_addr, &addrs_len, gfp);
278
279 initack.init_tag = htonl(asoc->c.my_vtag);
280 initack.a_rwnd = htonl(asoc->rwnd);
281 initack.num_outbound_streams = htons(asoc->c.sinit_num_ostreams);
282 initack.num_inbound_streams = htons(asoc->c.sinit_max_instreams);
283 initack.initial_tsn = htonl(asoc->c.initial_tsn);
284
285 /* FIXME: We really ought to build the cookie right
286 * into the packet instead of allocating more fresh memory.
287 */
288 cookie = sctp_pack_cookie(asoc->ep, asoc, chunk, &cookie_len,
289 addrs.v, addrs_len);
290 if (!cookie)
291 goto nomem_cookie;
292
293 /* Calculate the total size of allocation, include the reserved
294 * space for reporting unknown parameters if it is specified.
295 */
296 chunksize = sizeof(initack) + addrs_len + cookie_len + unkparam_len;
297
298 /* Tell peer that we'll do ECN only if peer advertised such cap. */
299 if (asoc->peer.ecn_capable)
300 chunksize += sizeof(ecap_param);
301
302 /* Tell peer that we'll do PR-SCTP only if peer advertised. */
303 if (asoc->peer.prsctp_capable)
304 chunksize += sizeof(prsctp_param);
305
306 chunksize += sizeof(aiparam);
307
308 /* Now allocate and fill out the chunk. */
309 retval = sctp_make_chunk(asoc, SCTP_CID_INIT_ACK, 0, chunksize);
310 if (!retval)
311 goto nomem_chunk;
312
313 /* Per the advice in RFC 2960 6.4, send this reply to
314 * the source of the INIT packet.
315 */
316 retval->transport = chunk->transport;
317 retval->subh.init_hdr =
318 sctp_addto_chunk(retval, sizeof(initack), &initack);
319 retval->param_hdr.v = sctp_addto_chunk(retval, addrs_len, addrs.v);
320 sctp_addto_chunk(retval, cookie_len, cookie);
321 if (asoc->peer.ecn_capable)
322 sctp_addto_chunk(retval, sizeof(ecap_param), &ecap_param);
323 if (asoc->peer.prsctp_capable)
324 sctp_addto_chunk(retval, sizeof(prsctp_param), &prsctp_param);
325
326 aiparam.param_hdr.type = SCTP_PARAM_ADAPTION_LAYER_IND;
327 aiparam.param_hdr.length = htons(sizeof(aiparam));
328 aiparam.adaption_ind = htonl(sctp_sk(asoc->base.sk)->adaption_ind);
329 sctp_addto_chunk(retval, sizeof(aiparam), &aiparam);
330
331 /* We need to remove the const qualifier at this point. */
332 retval->asoc = (struct sctp_association *) asoc;
333
334 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
335 *
336 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
337 * HEARTBEAT ACK, * etc.) to the same destination transport
338 * address from which it received the DATA or control chunk
339 * to which it is replying.
340 *
341 * [INIT ACK back to where the INIT came from.]
342 */
343 if (chunk)
344 retval->transport = chunk->transport;
345
346nomem_chunk:
347 kfree(cookie);
348nomem_cookie:
Jesper Juhla51482b2005-11-08 09:41:34 -0800349 kfree(addrs.v);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700350 return retval;
351}
352
353/* 3.3.11 Cookie Echo (COOKIE ECHO) (10):
354 *
355 * This chunk is used only during the initialization of an association.
356 * It is sent by the initiator of an association to its peer to complete
357 * the initialization process. This chunk MUST precede any DATA chunk
358 * sent within the association, but MAY be bundled with one or more DATA
359 * chunks in the same packet.
360 *
361 * 0 1 2 3
362 * 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
363 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
364 * | Type = 10 |Chunk Flags | Length |
365 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
366 * / Cookie /
367 * \ \
368 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
369 *
370 * Chunk Flags: 8 bit
371 *
372 * Set to zero on transmit and ignored on receipt.
373 *
374 * Length: 16 bits (unsigned integer)
375 *
376 * Set to the size of the chunk in bytes, including the 4 bytes of
377 * the chunk header and the size of the Cookie.
378 *
379 * Cookie: variable size
380 *
381 * This field must contain the exact cookie received in the
382 * State Cookie parameter from the previous INIT ACK.
383 *
384 * An implementation SHOULD make the cookie as small as possible
385 * to insure interoperability.
386 */
387struct sctp_chunk *sctp_make_cookie_echo(const struct sctp_association *asoc,
388 const struct sctp_chunk *chunk)
389{
390 struct sctp_chunk *retval;
391 void *cookie;
392 int cookie_len;
393
394 cookie = asoc->peer.cookie;
395 cookie_len = asoc->peer.cookie_len;
396
397 /* Build a cookie echo chunk. */
398 retval = sctp_make_chunk(asoc, SCTP_CID_COOKIE_ECHO, 0, cookie_len);
399 if (!retval)
400 goto nodata;
401 retval->subh.cookie_hdr =
402 sctp_addto_chunk(retval, cookie_len, cookie);
403
404 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
405 *
406 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
407 * HEARTBEAT ACK, * etc.) to the same destination transport
408 * address from which it * received the DATA or control chunk
409 * to which it is replying.
410 *
411 * [COOKIE ECHO back to where the INIT ACK came from.]
412 */
413 if (chunk)
414 retval->transport = chunk->transport;
415
416nodata:
417 return retval;
418}
419
420/* 3.3.12 Cookie Acknowledgement (COOKIE ACK) (11):
421 *
422 * This chunk is used only during the initialization of an
423 * association. It is used to acknowledge the receipt of a COOKIE
424 * ECHO chunk. This chunk MUST precede any DATA or SACK chunk sent
425 * within the association, but MAY be bundled with one or more DATA
426 * chunks or SACK chunk in the same SCTP packet.
427 *
428 * 0 1 2 3
429 * 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
430 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
431 * | Type = 11 |Chunk Flags | Length = 4 |
432 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
433 *
434 * Chunk Flags: 8 bits
435 *
436 * Set to zero on transmit and ignored on receipt.
437 */
438struct sctp_chunk *sctp_make_cookie_ack(const struct sctp_association *asoc,
439 const struct sctp_chunk *chunk)
440{
441 struct sctp_chunk *retval;
442
443 retval = sctp_make_chunk(asoc, SCTP_CID_COOKIE_ACK, 0, 0);
444
445 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
446 *
447 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
448 * HEARTBEAT ACK, * etc.) to the same destination transport
449 * address from which it * received the DATA or control chunk
450 * to which it is replying.
451 *
452 * [COOKIE ACK back to where the COOKIE ECHO came from.]
453 */
454 if (retval && chunk)
455 retval->transport = chunk->transport;
456
457 return retval;
458}
459
460/*
461 * Appendix A: Explicit Congestion Notification:
462 * CWR:
463 *
464 * RFC 2481 details a specific bit for a sender to send in the header of
465 * its next outbound TCP segment to indicate to its peer that it has
466 * reduced its congestion window. This is termed the CWR bit. For
467 * SCTP the same indication is made by including the CWR chunk.
468 * This chunk contains one data element, i.e. the TSN number that
469 * was sent in the ECNE chunk. This element represents the lowest
470 * TSN number in the datagram that was originally marked with the
471 * CE bit.
472 *
473 * 0 1 2 3
474 * 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
475 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
476 * | Chunk Type=13 | Flags=00000000| Chunk Length = 8 |
477 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
478 * | Lowest TSN Number |
479 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
480 *
481 * Note: The CWR is considered a Control chunk.
482 */
483struct sctp_chunk *sctp_make_cwr(const struct sctp_association *asoc,
484 const __u32 lowest_tsn,
485 const struct sctp_chunk *chunk)
486{
487 struct sctp_chunk *retval;
488 sctp_cwrhdr_t cwr;
489
490 cwr.lowest_tsn = htonl(lowest_tsn);
491 retval = sctp_make_chunk(asoc, SCTP_CID_ECN_CWR, 0,
492 sizeof(sctp_cwrhdr_t));
493
494 if (!retval)
495 goto nodata;
496
497 retval->subh.ecn_cwr_hdr =
498 sctp_addto_chunk(retval, sizeof(cwr), &cwr);
499
500 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
501 *
502 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
503 * HEARTBEAT ACK, * etc.) to the same destination transport
504 * address from which it * received the DATA or control chunk
505 * to which it is replying.
506 *
507 * [Report a reduced congestion window back to where the ECNE
508 * came from.]
509 */
510 if (chunk)
511 retval->transport = chunk->transport;
512
513nodata:
514 return retval;
515}
516
517/* Make an ECNE chunk. This is a congestion experienced report. */
518struct sctp_chunk *sctp_make_ecne(const struct sctp_association *asoc,
519 const __u32 lowest_tsn)
520{
521 struct sctp_chunk *retval;
522 sctp_ecnehdr_t ecne;
523
524 ecne.lowest_tsn = htonl(lowest_tsn);
525 retval = sctp_make_chunk(asoc, SCTP_CID_ECN_ECNE, 0,
526 sizeof(sctp_ecnehdr_t));
527 if (!retval)
528 goto nodata;
529 retval->subh.ecne_hdr =
530 sctp_addto_chunk(retval, sizeof(ecne), &ecne);
531
532nodata:
533 return retval;
534}
535
536/* Make a DATA chunk for the given association from the provided
537 * parameters. However, do not populate the data payload.
538 */
539struct sctp_chunk *sctp_make_datafrag_empty(struct sctp_association *asoc,
540 const struct sctp_sndrcvinfo *sinfo,
541 int data_len, __u8 flags, __u16 ssn)
542{
543 struct sctp_chunk *retval;
544 struct sctp_datahdr dp;
545 int chunk_len;
546
547 /* We assign the TSN as LATE as possible, not here when
548 * creating the chunk.
549 */
550 dp.tsn = 0;
551 dp.stream = htons(sinfo->sinfo_stream);
552 dp.ppid = sinfo->sinfo_ppid;
553
554 /* Set the flags for an unordered send. */
Ivan Skytte Jorgenseneaa5c542005-10-28 15:10:00 -0700555 if (sinfo->sinfo_flags & SCTP_UNORDERED) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700556 flags |= SCTP_DATA_UNORDERED;
557 dp.ssn = 0;
558 } else
559 dp.ssn = htons(ssn);
560
561 chunk_len = sizeof(dp) + data_len;
562 retval = sctp_make_chunk(asoc, SCTP_CID_DATA, flags, chunk_len);
563 if (!retval)
564 goto nodata;
565
566 retval->subh.data_hdr = sctp_addto_chunk(retval, sizeof(dp), &dp);
567 memcpy(&retval->sinfo, sinfo, sizeof(struct sctp_sndrcvinfo));
568
569nodata:
570 return retval;
571}
572
573/* Create a selective ackowledgement (SACK) for the given
574 * association. This reports on which TSN's we've seen to date,
575 * including duplicates and gaps.
576 */
577struct sctp_chunk *sctp_make_sack(const struct sctp_association *asoc)
578{
579 struct sctp_chunk *retval;
580 struct sctp_sackhdr sack;
581 int len;
582 __u32 ctsn;
583 __u16 num_gabs, num_dup_tsns;
584 struct sctp_tsnmap *map = (struct sctp_tsnmap *)&asoc->peer.tsn_map;
585
586 ctsn = sctp_tsnmap_get_ctsn(map);
587 SCTP_DEBUG_PRINTK("sackCTSNAck sent: 0x%x.\n", ctsn);
588
589 /* How much room is needed in the chunk? */
590 num_gabs = sctp_tsnmap_num_gabs(map);
591 num_dup_tsns = sctp_tsnmap_num_dups(map);
592
593 /* Initialize the SACK header. */
594 sack.cum_tsn_ack = htonl(ctsn);
595 sack.a_rwnd = htonl(asoc->a_rwnd);
596 sack.num_gap_ack_blocks = htons(num_gabs);
597 sack.num_dup_tsns = htons(num_dup_tsns);
598
599 len = sizeof(sack)
600 + sizeof(struct sctp_gap_ack_block) * num_gabs
601 + sizeof(__u32) * num_dup_tsns;
602
603 /* Create the chunk. */
604 retval = sctp_make_chunk(asoc, SCTP_CID_SACK, 0, len);
605 if (!retval)
606 goto nodata;
607
608 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
609 *
610 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
611 * HEARTBEAT ACK, etc.) to the same destination transport
612 * address from which it received the DATA or control chunk to
613 * which it is replying. This rule should also be followed if
614 * the endpoint is bundling DATA chunks together with the
615 * reply chunk.
616 *
617 * However, when acknowledging multiple DATA chunks received
618 * in packets from different source addresses in a single
619 * SACK, the SACK chunk may be transmitted to one of the
620 * destination transport addresses from which the DATA or
621 * control chunks being acknowledged were received.
622 *
623 * [BUG: We do not implement the following paragraph.
624 * Perhaps we should remember the last transport we used for a
625 * SACK and avoid that (if possible) if we have seen any
626 * duplicates. --piggy]
627 *
628 * When a receiver of a duplicate DATA chunk sends a SACK to a
629 * multi- homed endpoint it MAY be beneficial to vary the
630 * destination address and not use the source address of the
631 * DATA chunk. The reason being that receiving a duplicate
632 * from a multi-homed endpoint might indicate that the return
633 * path (as specified in the source address of the DATA chunk)
634 * for the SACK is broken.
635 *
636 * [Send to the address from which we last received a DATA chunk.]
637 */
638 retval->transport = asoc->peer.last_data_from;
639
640 retval->subh.sack_hdr =
641 sctp_addto_chunk(retval, sizeof(sack), &sack);
642
643 /* Add the gap ack block information. */
644 if (num_gabs)
645 sctp_addto_chunk(retval, sizeof(__u32) * num_gabs,
646 sctp_tsnmap_get_gabs(map));
647
648 /* Add the duplicate TSN information. */
649 if (num_dup_tsns)
650 sctp_addto_chunk(retval, sizeof(__u32) * num_dup_tsns,
651 sctp_tsnmap_get_dups(map));
652
653nodata:
654 return retval;
655}
656
657/* Make a SHUTDOWN chunk. */
658struct sctp_chunk *sctp_make_shutdown(const struct sctp_association *asoc,
659 const struct sctp_chunk *chunk)
660{
661 struct sctp_chunk *retval;
662 sctp_shutdownhdr_t shut;
663 __u32 ctsn;
664
665 ctsn = sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map);
666 shut.cum_tsn_ack = htonl(ctsn);
667
668 retval = sctp_make_chunk(asoc, SCTP_CID_SHUTDOWN, 0,
669 sizeof(sctp_shutdownhdr_t));
670 if (!retval)
671 goto nodata;
672
673 retval->subh.shutdown_hdr =
674 sctp_addto_chunk(retval, sizeof(shut), &shut);
675
676 if (chunk)
677 retval->transport = chunk->transport;
678nodata:
679 return retval;
680}
681
682struct sctp_chunk *sctp_make_shutdown_ack(const struct sctp_association *asoc,
683 const struct sctp_chunk *chunk)
684{
685 struct sctp_chunk *retval;
686
687 retval = sctp_make_chunk(asoc, SCTP_CID_SHUTDOWN_ACK, 0, 0);
688
689 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
690 *
691 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
692 * HEARTBEAT ACK, * etc.) to the same destination transport
693 * address from which it * received the DATA or control chunk
694 * to which it is replying.
695 *
696 * [ACK back to where the SHUTDOWN came from.]
697 */
698 if (retval && chunk)
699 retval->transport = chunk->transport;
700
701 return retval;
702}
703
704struct sctp_chunk *sctp_make_shutdown_complete(
705 const struct sctp_association *asoc,
706 const struct sctp_chunk *chunk)
707{
708 struct sctp_chunk *retval;
709 __u8 flags = 0;
710
Jerome Forissier047a2422005-04-28 11:58:43 -0700711 /* Set the T-bit if we have no association (vtag will be
712 * reflected)
713 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700714 flags |= asoc ? 0 : SCTP_CHUNK_FLAG_T;
715
716 retval = sctp_make_chunk(asoc, SCTP_CID_SHUTDOWN_COMPLETE, flags, 0);
717
718 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
719 *
720 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
721 * HEARTBEAT ACK, * etc.) to the same destination transport
722 * address from which it * received the DATA or control chunk
723 * to which it is replying.
724 *
725 * [Report SHUTDOWN COMPLETE back to where the SHUTDOWN ACK
726 * came from.]
727 */
728 if (retval && chunk)
729 retval->transport = chunk->transport;
730
731 return retval;
732}
733
734/* Create an ABORT. Note that we set the T bit if we have no
Jerome Forissier047a2422005-04-28 11:58:43 -0700735 * association, except when responding to an INIT (sctpimpguide 2.41).
Linus Torvalds1da177e2005-04-16 15:20:36 -0700736 */
737struct sctp_chunk *sctp_make_abort(const struct sctp_association *asoc,
738 const struct sctp_chunk *chunk,
739 const size_t hint)
740{
741 struct sctp_chunk *retval;
742 __u8 flags = 0;
743
Jerome Forissier047a2422005-04-28 11:58:43 -0700744 /* Set the T-bit if we have no association and 'chunk' is not
745 * an INIT (vtag will be reflected).
746 */
747 if (!asoc) {
748 if (chunk && chunk->chunk_hdr &&
749 chunk->chunk_hdr->type == SCTP_CID_INIT)
750 flags = 0;
751 else
752 flags = SCTP_CHUNK_FLAG_T;
753 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700754
755 retval = sctp_make_chunk(asoc, SCTP_CID_ABORT, flags, hint);
756
757 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
758 *
759 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
760 * HEARTBEAT ACK, * etc.) to the same destination transport
761 * address from which it * received the DATA or control chunk
762 * to which it is replying.
763 *
764 * [ABORT back to where the offender came from.]
765 */
766 if (retval && chunk)
767 retval->transport = chunk->transport;
768
769 return retval;
770}
771
772/* Helper to create ABORT with a NO_USER_DATA error. */
773struct sctp_chunk *sctp_make_abort_no_data(
774 const struct sctp_association *asoc,
775 const struct sctp_chunk *chunk, __u32 tsn)
776{
777 struct sctp_chunk *retval;
778 __u32 payload;
779
780 retval = sctp_make_abort(asoc, chunk, sizeof(sctp_errhdr_t)
781 + sizeof(tsn));
782
783 if (!retval)
784 goto no_mem;
785
786 /* Put the tsn back into network byte order. */
787 payload = htonl(tsn);
788 sctp_init_cause(retval, SCTP_ERROR_NO_DATA, (const void *)&payload,
789 sizeof(payload));
790
791 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
792 *
793 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
794 * HEARTBEAT ACK, * etc.) to the same destination transport
795 * address from which it * received the DATA or control chunk
796 * to which it is replying.
797 *
798 * [ABORT back to where the offender came from.]
799 */
800 if (chunk)
801 retval->transport = chunk->transport;
802
803no_mem:
804 return retval;
805}
806
807/* Helper to create ABORT with a SCTP_ERROR_USER_ABORT error. */
808struct sctp_chunk *sctp_make_abort_user(const struct sctp_association *asoc,
809 const struct sctp_chunk *chunk,
810 const struct msghdr *msg)
811{
812 struct sctp_chunk *retval;
813 void *payload = NULL, *payoff;
814 size_t paylen = 0;
815 struct iovec *iov = NULL;
816 int iovlen = 0;
817
818 if (msg) {
819 iov = msg->msg_iov;
820 iovlen = msg->msg_iovlen;
821 paylen = get_user_iov_size(iov, iovlen);
822 }
823
824 retval = sctp_make_abort(asoc, chunk, sizeof(sctp_errhdr_t) + paylen);
825 if (!retval)
826 goto err_chunk;
827
828 if (paylen) {
829 /* Put the msg_iov together into payload. */
830 payload = kmalloc(paylen, GFP_ATOMIC);
831 if (!payload)
832 goto err_payload;
833 payoff = payload;
834
835 for (; iovlen > 0; --iovlen) {
836 if (copy_from_user(payoff, iov->iov_base,iov->iov_len))
837 goto err_copy;
838 payoff += iov->iov_len;
839 iov++;
840 }
841 }
842
843 sctp_init_cause(retval, SCTP_ERROR_USER_ABORT, payload, paylen);
844
845 if (paylen)
846 kfree(payload);
847
848 return retval;
849
850err_copy:
851 kfree(payload);
852err_payload:
853 sctp_chunk_free(retval);
854 retval = NULL;
855err_chunk:
856 return retval;
857}
858
859/* Make an ABORT chunk with a PROTOCOL VIOLATION cause code. */
860struct sctp_chunk *sctp_make_abort_violation(
861 const struct sctp_association *asoc,
862 const struct sctp_chunk *chunk,
863 const __u8 *payload,
864 const size_t paylen)
865{
866 struct sctp_chunk *retval;
867 struct sctp_paramhdr phdr;
868
869 retval = sctp_make_abort(asoc, chunk, sizeof(sctp_errhdr_t) + paylen
870 + sizeof(sctp_chunkhdr_t));
871 if (!retval)
872 goto end;
873
874 sctp_init_cause(retval, SCTP_ERROR_PROTO_VIOLATION, payload, paylen);
875
876 phdr.type = htons(chunk->chunk_hdr->type);
877 phdr.length = chunk->chunk_hdr->length;
878 sctp_addto_chunk(retval, sizeof(sctp_paramhdr_t), &phdr);
879
880end:
881 return retval;
882}
883
884/* Make a HEARTBEAT chunk. */
885struct sctp_chunk *sctp_make_heartbeat(const struct sctp_association *asoc,
886 const struct sctp_transport *transport,
887 const void *payload, const size_t paylen)
888{
889 struct sctp_chunk *retval = sctp_make_chunk(asoc, SCTP_CID_HEARTBEAT,
890 0, paylen);
891
892 if (!retval)
893 goto nodata;
894
895 /* Cast away the 'const', as this is just telling the chunk
896 * what transport it belongs to.
897 */
898 retval->transport = (struct sctp_transport *) transport;
899 retval->subh.hbs_hdr = sctp_addto_chunk(retval, paylen, payload);
900
901nodata:
902 return retval;
903}
904
905struct sctp_chunk *sctp_make_heartbeat_ack(const struct sctp_association *asoc,
906 const struct sctp_chunk *chunk,
907 const void *payload, const size_t paylen)
908{
909 struct sctp_chunk *retval;
910
911 retval = sctp_make_chunk(asoc, SCTP_CID_HEARTBEAT_ACK, 0, paylen);
912 if (!retval)
913 goto nodata;
914
915 retval->subh.hbs_hdr = sctp_addto_chunk(retval, paylen, payload);
916
917 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
918 *
919 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
920 * HEARTBEAT ACK, * etc.) to the same destination transport
921 * address from which it * received the DATA or control chunk
922 * to which it is replying.
923 *
924 * [HBACK back to where the HEARTBEAT came from.]
925 */
926 if (chunk)
927 retval->transport = chunk->transport;
928
929nodata:
930 return retval;
931}
932
933/* Create an Operation Error chunk with the specified space reserved.
934 * This routine can be used for containing multiple causes in the chunk.
935 */
936static struct sctp_chunk *sctp_make_op_error_space(
937 const struct sctp_association *asoc,
938 const struct sctp_chunk *chunk,
939 size_t size)
940{
941 struct sctp_chunk *retval;
942
943 retval = sctp_make_chunk(asoc, SCTP_CID_ERROR, 0,
944 sizeof(sctp_errhdr_t) + size);
945 if (!retval)
946 goto nodata;
947
948 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
949 *
950 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
951 * HEARTBEAT ACK, etc.) to the same destination transport
952 * address from which it received the DATA or control chunk
953 * to which it is replying.
954 *
955 */
956 if (chunk)
957 retval->transport = chunk->transport;
958
959nodata:
960 return retval;
961}
962
963/* Create an Operation Error chunk. */
964struct sctp_chunk *sctp_make_op_error(const struct sctp_association *asoc,
965 const struct sctp_chunk *chunk,
966 __u16 cause_code, const void *payload,
967 size_t paylen)
968{
969 struct sctp_chunk *retval;
970
971 retval = sctp_make_op_error_space(asoc, chunk, paylen);
972 if (!retval)
973 goto nodata;
974
975 sctp_init_cause(retval, cause_code, payload, paylen);
976
977nodata:
978 return retval;
979}
980
981/********************************************************************
982 * 2nd Level Abstractions
983 ********************************************************************/
984
985/* Turn an skb into a chunk.
986 * FIXME: Eventually move the structure directly inside the skb->cb[].
987 */
988struct sctp_chunk *sctp_chunkify(struct sk_buff *skb,
989 const struct sctp_association *asoc,
990 struct sock *sk)
991{
992 struct sctp_chunk *retval;
993
994 retval = kmem_cache_alloc(sctp_chunk_cachep, SLAB_ATOMIC);
995
996 if (!retval)
997 goto nodata;
998 memset(retval, 0, sizeof(struct sctp_chunk));
999
1000 if (!sk) {
1001 SCTP_DEBUG_PRINTK("chunkifying skb %p w/o an sk\n", skb);
1002 }
1003
David S. Miller79af02c2005-07-08 21:47:49 -07001004 INIT_LIST_HEAD(&retval->list);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001005 retval->skb = skb;
1006 retval->asoc = (struct sctp_association *)asoc;
1007 retval->resent = 0;
1008 retval->has_tsn = 0;
1009 retval->has_ssn = 0;
1010 retval->rtt_in_progress = 0;
1011 retval->sent_at = 0;
1012 retval->singleton = 1;
1013 retval->end_of_packet = 0;
1014 retval->ecn_ce_done = 0;
1015 retval->pdiscard = 0;
1016
1017 /* sctpimpguide-05.txt Section 2.8.2
1018 * M1) Each time a new DATA chunk is transmitted
1019 * set the 'TSN.Missing.Report' count for that TSN to 0. The
1020 * 'TSN.Missing.Report' count will be used to determine missing chunks
1021 * and when to fast retransmit.
1022 */
1023 retval->tsn_missing_report = 0;
1024 retval->tsn_gap_acked = 0;
1025 retval->fast_retransmit = 0;
1026
1027 /* If this is a fragmented message, track all fragments
1028 * of the message (for SEND_FAILED).
1029 */
1030 retval->msg = NULL;
1031
1032 /* Polish the bead hole. */
1033 INIT_LIST_HEAD(&retval->transmitted_list);
1034 INIT_LIST_HEAD(&retval->frag_list);
1035 SCTP_DBG_OBJCNT_INC(chunk);
1036 atomic_set(&retval->refcnt, 1);
1037
1038nodata:
1039 return retval;
1040}
1041
1042/* Set chunk->source and dest based on the IP header in chunk->skb. */
1043void sctp_init_addrs(struct sctp_chunk *chunk, union sctp_addr *src,
1044 union sctp_addr *dest)
1045{
1046 memcpy(&chunk->source, src, sizeof(union sctp_addr));
1047 memcpy(&chunk->dest, dest, sizeof(union sctp_addr));
1048}
1049
1050/* Extract the source address from a chunk. */
1051const union sctp_addr *sctp_source(const struct sctp_chunk *chunk)
1052{
1053 /* If we have a known transport, use that. */
1054 if (chunk->transport) {
1055 return &chunk->transport->ipaddr;
1056 } else {
1057 /* Otherwise, extract it from the IP header. */
1058 return &chunk->source;
1059 }
1060}
1061
1062/* Create a new chunk, setting the type and flags headers from the
1063 * arguments, reserving enough space for a 'paylen' byte payload.
1064 */
1065SCTP_STATIC
1066struct sctp_chunk *sctp_make_chunk(const struct sctp_association *asoc,
1067 __u8 type, __u8 flags, int paylen)
1068{
1069 struct sctp_chunk *retval;
1070 sctp_chunkhdr_t *chunk_hdr;
1071 struct sk_buff *skb;
1072 struct sock *sk;
1073
1074 /* No need to allocate LL here, as this is only a chunk. */
1075 skb = alloc_skb(WORD_ROUND(sizeof(sctp_chunkhdr_t) + paylen),
1076 GFP_ATOMIC);
1077 if (!skb)
1078 goto nodata;
1079
1080 /* Make room for the chunk header. */
1081 chunk_hdr = (sctp_chunkhdr_t *)skb_put(skb, sizeof(sctp_chunkhdr_t));
1082 chunk_hdr->type = type;
1083 chunk_hdr->flags = flags;
1084 chunk_hdr->length = htons(sizeof(sctp_chunkhdr_t));
1085
1086 sk = asoc ? asoc->base.sk : NULL;
1087 retval = sctp_chunkify(skb, asoc, sk);
1088 if (!retval) {
1089 kfree_skb(skb);
1090 goto nodata;
1091 }
1092
1093 retval->chunk_hdr = chunk_hdr;
1094 retval->chunk_end = ((__u8 *)chunk_hdr) + sizeof(struct sctp_chunkhdr);
1095
1096 /* Set the skb to the belonging sock for accounting. */
1097 skb->sk = sk;
1098
1099 return retval;
1100nodata:
1101 return NULL;
1102}
1103
1104
1105/* Release the memory occupied by a chunk. */
1106static void sctp_chunk_destroy(struct sctp_chunk *chunk)
1107{
1108 /* Free the chunk skb data and the SCTP_chunk stub itself. */
1109 dev_kfree_skb(chunk->skb);
1110
1111 SCTP_DBG_OBJCNT_DEC(chunk);
1112 kmem_cache_free(sctp_chunk_cachep, chunk);
1113}
1114
1115/* Possibly, free the chunk. */
1116void sctp_chunk_free(struct sctp_chunk *chunk)
1117{
David S. Miller79af02c2005-07-08 21:47:49 -07001118 BUG_ON(!list_empty(&chunk->list));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001119 list_del_init(&chunk->transmitted_list);
1120
1121 /* Release our reference on the message tracker. */
1122 if (chunk->msg)
1123 sctp_datamsg_put(chunk->msg);
1124
1125 sctp_chunk_put(chunk);
1126}
1127
1128/* Grab a reference to the chunk. */
1129void sctp_chunk_hold(struct sctp_chunk *ch)
1130{
1131 atomic_inc(&ch->refcnt);
1132}
1133
1134/* Release a reference to the chunk. */
1135void sctp_chunk_put(struct sctp_chunk *ch)
1136{
1137 if (atomic_dec_and_test(&ch->refcnt))
1138 sctp_chunk_destroy(ch);
1139}
1140
1141/* Append bytes to the end of a chunk. Will panic if chunk is not big
1142 * enough.
1143 */
1144void *sctp_addto_chunk(struct sctp_chunk *chunk, int len, const void *data)
1145{
1146 void *target;
1147 void *padding;
1148 int chunklen = ntohs(chunk->chunk_hdr->length);
1149 int padlen = chunklen % 4;
1150
1151 padding = skb_put(chunk->skb, padlen);
1152 target = skb_put(chunk->skb, len);
1153
1154 memset(padding, 0, padlen);
1155 memcpy(target, data, len);
1156
1157 /* Adjust the chunk length field. */
1158 chunk->chunk_hdr->length = htons(chunklen + padlen + len);
1159 chunk->chunk_end = chunk->skb->tail;
1160
1161 return target;
1162}
1163
1164/* Append bytes from user space to the end of a chunk. Will panic if
1165 * chunk is not big enough.
1166 * Returns a kernel err value.
1167 */
1168int sctp_user_addto_chunk(struct sctp_chunk *chunk, int off, int len,
1169 struct iovec *data)
1170{
1171 __u8 *target;
1172 int err = 0;
1173
1174 /* Make room in chunk for data. */
1175 target = skb_put(chunk->skb, len);
1176
1177 /* Copy data (whole iovec) into chunk */
1178 if ((err = memcpy_fromiovecend(target, data, off, len)))
1179 goto out;
1180
1181 /* Adjust the chunk length field. */
1182 chunk->chunk_hdr->length =
1183 htons(ntohs(chunk->chunk_hdr->length) + len);
1184 chunk->chunk_end = chunk->skb->tail;
1185
1186out:
1187 return err;
1188}
1189
1190/* Helper function to assign a TSN if needed. This assumes that both
1191 * the data_hdr and association have already been assigned.
1192 */
1193void sctp_chunk_assign_ssn(struct sctp_chunk *chunk)
1194{
1195 __u16 ssn;
1196 __u16 sid;
1197
1198 if (chunk->has_ssn)
1199 return;
1200
1201 /* This is the last possible instant to assign a SSN. */
1202 if (chunk->chunk_hdr->flags & SCTP_DATA_UNORDERED) {
1203 ssn = 0;
1204 } else {
1205 sid = htons(chunk->subh.data_hdr->stream);
1206 if (chunk->chunk_hdr->flags & SCTP_DATA_LAST_FRAG)
1207 ssn = sctp_ssn_next(&chunk->asoc->ssnmap->out, sid);
1208 else
1209 ssn = sctp_ssn_peek(&chunk->asoc->ssnmap->out, sid);
1210 ssn = htons(ssn);
1211 }
1212
1213 chunk->subh.data_hdr->ssn = ssn;
1214 chunk->has_ssn = 1;
1215}
1216
1217/* Helper function to assign a TSN if needed. This assumes that both
1218 * the data_hdr and association have already been assigned.
1219 */
1220void sctp_chunk_assign_tsn(struct sctp_chunk *chunk)
1221{
1222 if (!chunk->has_tsn) {
1223 /* This is the last possible instant to
1224 * assign a TSN.
1225 */
1226 chunk->subh.data_hdr->tsn =
1227 htonl(sctp_association_get_next_tsn(chunk->asoc));
1228 chunk->has_tsn = 1;
1229 }
1230}
1231
1232/* Create a CLOSED association to use with an incoming packet. */
1233struct sctp_association *sctp_make_temp_asoc(const struct sctp_endpoint *ep,
Alexey Dobriyan3182cd842005-07-11 20:57:47 -07001234 struct sctp_chunk *chunk,
Al Virodd0fc662005-10-07 07:46:04 +01001235 gfp_t gfp)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001236{
1237 struct sctp_association *asoc;
1238 struct sk_buff *skb;
1239 sctp_scope_t scope;
1240 struct sctp_af *af;
1241
1242 /* Create the bare association. */
1243 scope = sctp_scope(sctp_source(chunk));
1244 asoc = sctp_association_new(ep, ep->base.sk, scope, gfp);
1245 if (!asoc)
1246 goto nodata;
1247 asoc->temp = 1;
1248 skb = chunk->skb;
1249 /* Create an entry for the source address of the packet. */
1250 af = sctp_get_af_specific(ipver2af(skb->nh.iph->version));
1251 if (unlikely(!af))
1252 goto fail;
1253 af->from_skb(&asoc->c.peer_addr, skb, 1);
1254nodata:
1255 return asoc;
1256
1257fail:
1258 sctp_association_free(asoc);
1259 return NULL;
1260}
1261
1262/* Build a cookie representing asoc.
1263 * This INCLUDES the param header needed to put the cookie in the INIT ACK.
1264 */
1265static sctp_cookie_param_t *sctp_pack_cookie(const struct sctp_endpoint *ep,
1266 const struct sctp_association *asoc,
1267 const struct sctp_chunk *init_chunk,
1268 int *cookie_len,
1269 const __u8 *raw_addrs, int addrs_len)
1270{
1271 sctp_cookie_param_t *retval;
1272 struct sctp_signed_cookie *cookie;
1273 struct scatterlist sg;
1274 int headersize, bodysize;
1275 unsigned int keylen;
1276 char *key;
1277
Vlad Yasevich9834a2b2006-01-17 11:52:12 -08001278 /* Header size is static data prior to the actual cookie, including
1279 * any padding.
1280 */
1281 headersize = sizeof(sctp_paramhdr_t) +
1282 (sizeof(struct sctp_signed_cookie) -
1283 sizeof(struct sctp_cookie));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001284 bodysize = sizeof(struct sctp_cookie)
1285 + ntohs(init_chunk->chunk_hdr->length) + addrs_len;
1286
1287 /* Pad out the cookie to a multiple to make the signature
1288 * functions simpler to write.
1289 */
1290 if (bodysize % SCTP_COOKIE_MULTIPLE)
1291 bodysize += SCTP_COOKIE_MULTIPLE
1292 - (bodysize % SCTP_COOKIE_MULTIPLE);
1293 *cookie_len = headersize + bodysize;
1294
Kris Katterjohn8b3a7002006-01-11 15:56:43 -08001295 retval = kmalloc(*cookie_len, GFP_ATOMIC);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001296
1297 if (!retval) {
1298 *cookie_len = 0;
1299 goto nodata;
1300 }
1301
1302 /* Clear this memory since we are sending this data structure
1303 * out on the network.
1304 */
1305 memset(retval, 0x00, *cookie_len);
1306 cookie = (struct sctp_signed_cookie *) retval->body;
1307
1308 /* Set up the parameter header. */
1309 retval->p.type = SCTP_PARAM_STATE_COOKIE;
1310 retval->p.length = htons(*cookie_len);
1311
1312 /* Copy the cookie part of the association itself. */
1313 cookie->c = asoc->c;
1314 /* Save the raw address list length in the cookie. */
1315 cookie->c.raw_addr_list_len = addrs_len;
1316
1317 /* Remember PR-SCTP capability. */
1318 cookie->c.prsctp_capable = asoc->peer.prsctp_capable;
1319
1320 /* Save adaption indication in the cookie. */
1321 cookie->c.adaption_ind = asoc->peer.adaption_ind;
1322
1323 /* Set an expiration time for the cookie. */
1324 do_gettimeofday(&cookie->c.expiration);
1325 TIMEVAL_ADD(asoc->cookie_life, cookie->c.expiration);
1326
1327 /* Copy the peer's init packet. */
1328 memcpy(&cookie->c.peer_init[0], init_chunk->chunk_hdr,
1329 ntohs(init_chunk->chunk_hdr->length));
1330
1331 /* Copy the raw local address list of the association. */
1332 memcpy((__u8 *)&cookie->c.peer_init[0] +
1333 ntohs(init_chunk->chunk_hdr->length), raw_addrs, addrs_len);
1334
1335 if (sctp_sk(ep->base.sk)->hmac) {
1336 /* Sign the message. */
1337 sg.page = virt_to_page(&cookie->c);
1338 sg.offset = (unsigned long)(&cookie->c) % PAGE_SIZE;
1339 sg.length = bodysize;
1340 keylen = SCTP_SECRET_SIZE;
1341 key = (char *)ep->secret_key[ep->current_key];
1342
1343 sctp_crypto_hmac(sctp_sk(ep->base.sk)->hmac, key, &keylen,
1344 &sg, 1, cookie->signature);
1345 }
1346
1347nodata:
1348 return retval;
1349}
1350
1351/* Unpack the cookie from COOKIE ECHO chunk, recreating the association. */
1352struct sctp_association *sctp_unpack_cookie(
1353 const struct sctp_endpoint *ep,
1354 const struct sctp_association *asoc,
Al Virodd0fc662005-10-07 07:46:04 +01001355 struct sctp_chunk *chunk, gfp_t gfp,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001356 int *error, struct sctp_chunk **errp)
1357{
1358 struct sctp_association *retval = NULL;
1359 struct sctp_signed_cookie *cookie;
1360 struct sctp_cookie *bear_cookie;
1361 int headersize, bodysize, fixed_size;
Vlad Yasevich313e7b42006-01-17 11:55:57 -08001362 __u8 *digest = ep->digest;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001363 struct scatterlist sg;
1364 unsigned int keylen, len;
1365 char *key;
1366 sctp_scope_t scope;
1367 struct sk_buff *skb = chunk->skb;
Patrick McHardya61bbcf2005-08-14 17:24:31 -07001368 struct timeval tv;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001369
Vlad Yasevich9834a2b2006-01-17 11:52:12 -08001370 /* Header size is static data prior to the actual cookie, including
1371 * any padding.
1372 */
1373 headersize = sizeof(sctp_chunkhdr_t) +
1374 (sizeof(struct sctp_signed_cookie) -
1375 sizeof(struct sctp_cookie));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001376 bodysize = ntohs(chunk->chunk_hdr->length) - headersize;
1377 fixed_size = headersize + sizeof(struct sctp_cookie);
1378
1379 /* Verify that the chunk looks like it even has a cookie.
1380 * There must be enough room for our cookie and our peer's
1381 * INIT chunk.
1382 */
1383 len = ntohs(chunk->chunk_hdr->length);
1384 if (len < fixed_size + sizeof(struct sctp_chunkhdr))
1385 goto malformed;
1386
1387 /* Verify that the cookie has been padded out. */
1388 if (bodysize % SCTP_COOKIE_MULTIPLE)
1389 goto malformed;
1390
1391 /* Process the cookie. */
1392 cookie = chunk->subh.cookie_hdr;
1393 bear_cookie = &cookie->c;
1394
1395 if (!sctp_sk(ep->base.sk)->hmac)
1396 goto no_hmac;
1397
1398 /* Check the signature. */
1399 keylen = SCTP_SECRET_SIZE;
1400 sg.page = virt_to_page(bear_cookie);
1401 sg.offset = (unsigned long)(bear_cookie) % PAGE_SIZE;
1402 sg.length = bodysize;
1403 key = (char *)ep->secret_key[ep->current_key];
1404
Al Viro8ca84482006-06-20 03:26:14 -07001405 memset(digest, 0x00, SCTP_SIGNATURE_SIZE);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001406 sctp_crypto_hmac(sctp_sk(ep->base.sk)->hmac, key, &keylen, &sg,
1407 1, digest);
1408
1409 if (memcmp(digest, cookie->signature, SCTP_SIGNATURE_SIZE)) {
1410 /* Try the previous key. */
1411 key = (char *)ep->secret_key[ep->last_key];
Al Viro8ca84482006-06-20 03:26:14 -07001412 memset(digest, 0x00, SCTP_SIGNATURE_SIZE);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001413 sctp_crypto_hmac(sctp_sk(ep->base.sk)->hmac, key, &keylen,
1414 &sg, 1, digest);
1415
1416 if (memcmp(digest, cookie->signature, SCTP_SIGNATURE_SIZE)) {
1417 /* Yikes! Still bad signature! */
1418 *error = -SCTP_IERROR_BAD_SIG;
1419 goto fail;
1420 }
1421 }
1422
1423no_hmac:
1424 /* IG Section 2.35.2:
1425 * 3) Compare the port numbers and the verification tag contained
1426 * within the COOKIE ECHO chunk to the actual port numbers and the
1427 * verification tag within the SCTP common header of the received
1428 * packet. If these values do not match the packet MUST be silently
1429 * discarded,
1430 */
1431 if (ntohl(chunk->sctp_hdr->vtag) != bear_cookie->my_vtag) {
1432 *error = -SCTP_IERROR_BAD_TAG;
1433 goto fail;
1434 }
1435
1436 if (ntohs(chunk->sctp_hdr->source) != bear_cookie->peer_addr.v4.sin_port ||
1437 ntohs(chunk->sctp_hdr->dest) != bear_cookie->my_port) {
1438 *error = -SCTP_IERROR_BAD_PORTS;
1439 goto fail;
1440 }
1441
1442 /* Check to see if the cookie is stale. If there is already
1443 * an association, there is no need to check cookie's expiration
1444 * for init collision case of lost COOKIE ACK.
1445 */
Patrick McHardya61bbcf2005-08-14 17:24:31 -07001446 skb_get_timestamp(skb, &tv);
1447 if (!asoc && tv_lt(bear_cookie->expiration, tv)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001448 __u16 len;
1449 /*
1450 * Section 3.3.10.3 Stale Cookie Error (3)
1451 *
1452 * Cause of error
1453 * ---------------
1454 * Stale Cookie Error: Indicates the receipt of a valid State
1455 * Cookie that has expired.
1456 */
1457 len = ntohs(chunk->chunk_hdr->length);
1458 *errp = sctp_make_op_error_space(asoc, chunk, len);
1459 if (*errp) {
Patrick McHardya61bbcf2005-08-14 17:24:31 -07001460 suseconds_t usecs = (tv.tv_sec -
Linus Torvalds1da177e2005-04-16 15:20:36 -07001461 bear_cookie->expiration.tv_sec) * 1000000L +
Patrick McHardya61bbcf2005-08-14 17:24:31 -07001462 tv.tv_usec - bear_cookie->expiration.tv_usec;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001463
1464 usecs = htonl(usecs);
1465 sctp_init_cause(*errp, SCTP_ERROR_STALE_COOKIE,
1466 &usecs, sizeof(usecs));
1467 *error = -SCTP_IERROR_STALE_COOKIE;
1468 } else
1469 *error = -SCTP_IERROR_NOMEM;
1470
1471 goto fail;
1472 }
1473
1474 /* Make a new base association. */
1475 scope = sctp_scope(sctp_source(chunk));
1476 retval = sctp_association_new(ep, ep->base.sk, scope, gfp);
1477 if (!retval) {
1478 *error = -SCTP_IERROR_NOMEM;
1479 goto fail;
1480 }
1481
1482 /* Set up our peer's port number. */
1483 retval->peer.port = ntohs(chunk->sctp_hdr->source);
1484
1485 /* Populate the association from the cookie. */
1486 memcpy(&retval->c, bear_cookie, sizeof(*bear_cookie));
1487
1488 if (sctp_assoc_set_bind_addr_from_cookie(retval, bear_cookie,
1489 GFP_ATOMIC) < 0) {
1490 *error = -SCTP_IERROR_NOMEM;
1491 goto fail;
1492 }
1493
1494 /* Also, add the destination address. */
1495 if (list_empty(&retval->base.bind_addr.address_list)) {
Sridhar Samudraladc022a92006-07-21 14:49:25 -07001496 sctp_add_bind_addr(&retval->base.bind_addr, &chunk->dest, 1,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001497 GFP_ATOMIC);
1498 }
1499
1500 retval->next_tsn = retval->c.initial_tsn;
1501 retval->ctsn_ack_point = retval->next_tsn - 1;
1502 retval->addip_serial = retval->c.initial_tsn;
1503 retval->adv_peer_ack_point = retval->ctsn_ack_point;
1504 retval->peer.prsctp_capable = retval->c.prsctp_capable;
1505 retval->peer.adaption_ind = retval->c.adaption_ind;
1506
1507 /* The INIT stuff will be done by the side effects. */
1508 return retval;
1509
1510fail:
1511 if (retval)
1512 sctp_association_free(retval);
1513
1514 return NULL;
1515
1516malformed:
1517 /* Yikes! The packet is either corrupt or deliberately
1518 * malformed.
1519 */
1520 *error = -SCTP_IERROR_MALFORMED;
1521 goto fail;
1522}
1523
1524/********************************************************************
1525 * 3rd Level Abstractions
1526 ********************************************************************/
1527
1528struct __sctp_missing {
1529 __u32 num_missing;
1530 __u16 type;
1531} __attribute__((packed));
1532
1533/*
1534 * Report a missing mandatory parameter.
1535 */
1536static int sctp_process_missing_param(const struct sctp_association *asoc,
1537 sctp_param_t paramtype,
1538 struct sctp_chunk *chunk,
1539 struct sctp_chunk **errp)
1540{
1541 struct __sctp_missing report;
1542 __u16 len;
1543
1544 len = WORD_ROUND(sizeof(report));
1545
1546 /* Make an ERROR chunk, preparing enough room for
1547 * returning multiple unknown parameters.
1548 */
1549 if (!*errp)
1550 *errp = sctp_make_op_error_space(asoc, chunk, len);
1551
1552 if (*errp) {
1553 report.num_missing = htonl(1);
1554 report.type = paramtype;
1555 sctp_init_cause(*errp, SCTP_ERROR_INV_PARAM,
1556 &report, sizeof(report));
1557 }
1558
1559 /* Stop processing this chunk. */
1560 return 0;
1561}
1562
1563/* Report an Invalid Mandatory Parameter. */
1564static int sctp_process_inv_mandatory(const struct sctp_association *asoc,
1565 struct sctp_chunk *chunk,
1566 struct sctp_chunk **errp)
1567{
1568 /* Invalid Mandatory Parameter Error has no payload. */
1569
1570 if (!*errp)
1571 *errp = sctp_make_op_error_space(asoc, chunk, 0);
1572
1573 if (*errp)
1574 sctp_init_cause(*errp, SCTP_ERROR_INV_PARAM, NULL, 0);
1575
1576 /* Stop processing this chunk. */
1577 return 0;
1578}
1579
1580static int sctp_process_inv_paramlength(const struct sctp_association *asoc,
1581 struct sctp_paramhdr *param,
1582 const struct sctp_chunk *chunk,
1583 struct sctp_chunk **errp)
1584{
1585 char error[] = "The following parameter had invalid length:";
1586 size_t payload_len = WORD_ROUND(sizeof(error)) +
1587 sizeof(sctp_paramhdr_t);
1588
1589
1590 /* Create an error chunk and fill it in with our payload. */
1591 if (!*errp)
1592 *errp = sctp_make_op_error_space(asoc, chunk, payload_len);
1593
1594 if (*errp) {
1595 sctp_init_cause(*errp, SCTP_ERROR_PROTO_VIOLATION, error,
1596 sizeof(error));
1597 sctp_addto_chunk(*errp, sizeof(sctp_paramhdr_t), param);
1598 }
1599
1600 return 0;
1601}
1602
1603
1604/* Do not attempt to handle the HOST_NAME parm. However, do
1605 * send back an indicator to the peer.
1606 */
1607static int sctp_process_hn_param(const struct sctp_association *asoc,
1608 union sctp_params param,
1609 struct sctp_chunk *chunk,
1610 struct sctp_chunk **errp)
1611{
1612 __u16 len = ntohs(param.p->length);
1613
1614 /* Make an ERROR chunk. */
1615 if (!*errp)
1616 *errp = sctp_make_op_error_space(asoc, chunk, len);
1617
1618 if (*errp)
1619 sctp_init_cause(*errp, SCTP_ERROR_DNS_FAILED,
1620 param.v, len);
1621
1622 /* Stop processing this chunk. */
1623 return 0;
1624}
1625
1626/* RFC 3.2.1 & the Implementers Guide 2.2.
1627 *
1628 * The Parameter Types are encoded such that the
1629 * highest-order two bits specify the action that must be
1630 * taken if the processing endpoint does not recognize the
1631 * Parameter Type.
1632 *
1633 * 00 - Stop processing this SCTP chunk and discard it,
1634 * do not process any further chunks within it.
1635 *
1636 * 01 - Stop processing this SCTP chunk and discard it,
1637 * do not process any further chunks within it, and report
1638 * the unrecognized parameter in an 'Unrecognized
1639 * Parameter Type' (in either an ERROR or in the INIT ACK).
1640 *
1641 * 10 - Skip this parameter and continue processing.
1642 *
1643 * 11 - Skip this parameter and continue processing but
1644 * report the unrecognized parameter in an
1645 * 'Unrecognized Parameter Type' (in either an ERROR or in
1646 * the INIT ACK).
1647 *
1648 * Return value:
1649 * 0 - discard the chunk
1650 * 1 - continue with the chunk
1651 */
1652static int sctp_process_unk_param(const struct sctp_association *asoc,
1653 union sctp_params param,
1654 struct sctp_chunk *chunk,
1655 struct sctp_chunk **errp)
1656{
1657 int retval = 1;
1658
1659 switch (param.p->type & SCTP_PARAM_ACTION_MASK) {
1660 case SCTP_PARAM_ACTION_DISCARD:
1661 retval = 0;
1662 break;
1663 case SCTP_PARAM_ACTION_DISCARD_ERR:
1664 retval = 0;
1665 /* Make an ERROR chunk, preparing enough room for
1666 * returning multiple unknown parameters.
1667 */
1668 if (NULL == *errp)
1669 *errp = sctp_make_op_error_space(asoc, chunk,
1670 ntohs(chunk->chunk_hdr->length));
1671
1672 if (*errp)
1673 sctp_init_cause(*errp, SCTP_ERROR_UNKNOWN_PARAM,
1674 param.v,
1675 WORD_ROUND(ntohs(param.p->length)));
1676
1677 break;
1678 case SCTP_PARAM_ACTION_SKIP:
1679 break;
1680 case SCTP_PARAM_ACTION_SKIP_ERR:
1681 /* Make an ERROR chunk, preparing enough room for
1682 * returning multiple unknown parameters.
1683 */
1684 if (NULL == *errp)
1685 *errp = sctp_make_op_error_space(asoc, chunk,
1686 ntohs(chunk->chunk_hdr->length));
1687
1688 if (*errp) {
1689 sctp_init_cause(*errp, SCTP_ERROR_UNKNOWN_PARAM,
1690 param.v,
1691 WORD_ROUND(ntohs(param.p->length)));
1692 } else {
1693 /* If there is no memory for generating the ERROR
1694 * report as specified, an ABORT will be triggered
1695 * to the peer and the association won't be
1696 * established.
1697 */
1698 retval = 0;
1699 }
1700
1701 break;
1702 default:
1703 break;
1704 }
1705
1706 return retval;
1707}
1708
1709/* Find unrecognized parameters in the chunk.
1710 * Return values:
1711 * 0 - discard the chunk
1712 * 1 - continue with the chunk
1713 */
1714static int sctp_verify_param(const struct sctp_association *asoc,
1715 union sctp_params param,
1716 sctp_cid_t cid,
1717 struct sctp_chunk *chunk,
1718 struct sctp_chunk **err_chunk)
1719{
1720 int retval = 1;
1721
1722 /* FIXME - This routine is not looking at each parameter per the
1723 * chunk type, i.e., unrecognized parameters should be further
1724 * identified based on the chunk id.
1725 */
1726
1727 switch (param.p->type) {
1728 case SCTP_PARAM_IPV4_ADDRESS:
1729 case SCTP_PARAM_IPV6_ADDRESS:
1730 case SCTP_PARAM_COOKIE_PRESERVATIVE:
1731 case SCTP_PARAM_SUPPORTED_ADDRESS_TYPES:
1732 case SCTP_PARAM_STATE_COOKIE:
1733 case SCTP_PARAM_HEARTBEAT_INFO:
1734 case SCTP_PARAM_UNRECOGNIZED_PARAMETERS:
1735 case SCTP_PARAM_ECN_CAPABLE:
1736 case SCTP_PARAM_ADAPTION_LAYER_IND:
1737 break;
1738
1739 case SCTP_PARAM_HOST_NAME_ADDRESS:
1740 /* Tell the peer, we won't support this param. */
1741 return sctp_process_hn_param(asoc, param, chunk, err_chunk);
1742 case SCTP_PARAM_FWD_TSN_SUPPORT:
1743 if (sctp_prsctp_enable)
1744 break;
1745 /* Fall Through */
1746 default:
1747 SCTP_DEBUG_PRINTK("Unrecognized param: %d for chunk %d.\n",
1748 ntohs(param.p->type), cid);
1749 return sctp_process_unk_param(asoc, param, chunk, err_chunk);
1750
1751 break;
1752 }
1753 return retval;
1754}
1755
1756/* Verify the INIT packet before we process it. */
1757int sctp_verify_init(const struct sctp_association *asoc,
1758 sctp_cid_t cid,
1759 sctp_init_chunk_t *peer_init,
1760 struct sctp_chunk *chunk,
1761 struct sctp_chunk **errp)
1762{
1763 union sctp_params param;
1764 int has_cookie = 0;
1765
1766 /* Verify stream values are non-zero. */
1767 if ((0 == peer_init->init_hdr.num_outbound_streams) ||
1768 (0 == peer_init->init_hdr.num_inbound_streams)) {
1769
1770 sctp_process_inv_mandatory(asoc, chunk, errp);
1771 return 0;
1772 }
1773
1774 /* Check for missing mandatory parameters. */
1775 sctp_walk_params(param, peer_init, init_hdr.params) {
1776
1777 if (SCTP_PARAM_STATE_COOKIE == param.p->type)
1778 has_cookie = 1;
1779
1780 } /* for (loop through all parameters) */
1781
1782 /* There is a possibility that a parameter length was bad and
1783 * in that case we would have stoped walking the parameters.
1784 * The current param.p would point at the bad one.
1785 * Current consensus on the mailing list is to generate a PROTOCOL
1786 * VIOLATION error. We build the ERROR chunk here and let the normal
1787 * error handling code build and send the packet.
1788 */
1789 if (param.v < (void*)chunk->chunk_end - sizeof(sctp_paramhdr_t)) {
1790 sctp_process_inv_paramlength(asoc, param.p, chunk, errp);
1791 return 0;
1792 }
1793
1794 /* The only missing mandatory param possible today is
1795 * the state cookie for an INIT-ACK chunk.
1796 */
1797 if ((SCTP_CID_INIT_ACK == cid) && !has_cookie) {
1798 sctp_process_missing_param(asoc, SCTP_PARAM_STATE_COOKIE,
1799 chunk, errp);
1800 return 0;
1801 }
1802
1803 /* Find unrecognized parameters. */
1804
1805 sctp_walk_params(param, peer_init, init_hdr.params) {
1806
1807 if (!sctp_verify_param(asoc, param, cid, chunk, errp)) {
1808 if (SCTP_PARAM_HOST_NAME_ADDRESS == param.p->type)
1809 return 0;
1810 else
1811 return 1;
1812 }
1813
1814 } /* for (loop through all parameters) */
1815
1816 return 1;
1817}
1818
1819/* Unpack the parameters in an INIT packet into an association.
1820 * Returns 0 on failure, else success.
1821 * FIXME: This is an association method.
1822 */
1823int sctp_process_init(struct sctp_association *asoc, sctp_cid_t cid,
1824 const union sctp_addr *peer_addr,
Al Virodd0fc662005-10-07 07:46:04 +01001825 sctp_init_chunk_t *peer_init, gfp_t gfp)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001826{
1827 union sctp_params param;
1828 struct sctp_transport *transport;
1829 struct list_head *pos, *temp;
1830 char *cookie;
1831
1832 /* We must include the address that the INIT packet came from.
1833 * This is the only address that matters for an INIT packet.
1834 * When processing a COOKIE ECHO, we retrieve the from address
1835 * of the INIT from the cookie.
1836 */
1837
1838 /* This implementation defaults to making the first transport
1839 * added as the primary transport. The source address seems to
1840 * be a a better choice than any of the embedded addresses.
1841 */
1842 if (peer_addr)
Frank Filz3f7a87d2005-06-20 13:14:57 -07001843 if(!sctp_assoc_add_peer(asoc, peer_addr, gfp, SCTP_ACTIVE))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001844 goto nomem;
1845
1846 /* Process the initialization parameters. */
1847
1848 sctp_walk_params(param, peer_init, init_hdr.params) {
1849
1850 if (!sctp_process_param(asoc, param, peer_addr, gfp))
1851 goto clean_up;
1852 }
1853
Frank Filz3f7a87d2005-06-20 13:14:57 -07001854 /* Walk list of transports, removing transports in the UNKNOWN state. */
1855 list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
1856 transport = list_entry(pos, struct sctp_transport, transports);
1857 if (transport->state == SCTP_UNKNOWN) {
1858 sctp_assoc_rm_peer(asoc, transport);
1859 }
1860 }
1861
Linus Torvalds1da177e2005-04-16 15:20:36 -07001862 /* The fixed INIT headers are always in network byte
1863 * order.
1864 */
1865 asoc->peer.i.init_tag =
1866 ntohl(peer_init->init_hdr.init_tag);
1867 asoc->peer.i.a_rwnd =
1868 ntohl(peer_init->init_hdr.a_rwnd);
1869 asoc->peer.i.num_outbound_streams =
1870 ntohs(peer_init->init_hdr.num_outbound_streams);
1871 asoc->peer.i.num_inbound_streams =
1872 ntohs(peer_init->init_hdr.num_inbound_streams);
1873 asoc->peer.i.initial_tsn =
1874 ntohl(peer_init->init_hdr.initial_tsn);
1875
1876 /* Apply the upper bounds for output streams based on peer's
1877 * number of inbound streams.
1878 */
1879 if (asoc->c.sinit_num_ostreams >
1880 ntohs(peer_init->init_hdr.num_inbound_streams)) {
1881 asoc->c.sinit_num_ostreams =
1882 ntohs(peer_init->init_hdr.num_inbound_streams);
1883 }
1884
1885 if (asoc->c.sinit_max_instreams >
1886 ntohs(peer_init->init_hdr.num_outbound_streams)) {
1887 asoc->c.sinit_max_instreams =
1888 ntohs(peer_init->init_hdr.num_outbound_streams);
1889 }
1890
1891 /* Copy Initiation tag from INIT to VT_peer in cookie. */
1892 asoc->c.peer_vtag = asoc->peer.i.init_tag;
1893
1894 /* Peer Rwnd : Current calculated value of the peer's rwnd. */
1895 asoc->peer.rwnd = asoc->peer.i.a_rwnd;
1896
1897 /* Copy cookie in case we need to resend COOKIE-ECHO. */
1898 cookie = asoc->peer.cookie;
1899 if (cookie) {
1900 asoc->peer.cookie = kmalloc(asoc->peer.cookie_len, gfp);
1901 if (!asoc->peer.cookie)
1902 goto clean_up;
1903 memcpy(asoc->peer.cookie, cookie, asoc->peer.cookie_len);
1904 }
1905
1906 /* RFC 2960 7.2.1 The initial value of ssthresh MAY be arbitrarily
1907 * high (for example, implementations MAY use the size of the receiver
1908 * advertised window).
1909 */
1910 list_for_each(pos, &asoc->peer.transport_addr_list) {
1911 transport = list_entry(pos, struct sctp_transport, transports);
1912 transport->ssthresh = asoc->peer.i.a_rwnd;
1913 }
1914
1915 /* Set up the TSN tracking pieces. */
1916 sctp_tsnmap_init(&asoc->peer.tsn_map, SCTP_TSN_MAP_SIZE,
1917 asoc->peer.i.initial_tsn);
1918
1919 /* RFC 2960 6.5 Stream Identifier and Stream Sequence Number
1920 *
1921 * The stream sequence number in all the streams shall start
1922 * from 0 when the association is established. Also, when the
1923 * stream sequence number reaches the value 65535 the next
1924 * stream sequence number shall be set to 0.
1925 */
1926
Frank Filz3f7a87d2005-06-20 13:14:57 -07001927 /* Allocate storage for the negotiated streams if it is not a temporary
1928 * association.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001929 */
1930 if (!asoc->temp) {
1931 int assoc_id;
1932 int error;
1933
1934 asoc->ssnmap = sctp_ssnmap_new(asoc->c.sinit_max_instreams,
1935 asoc->c.sinit_num_ostreams, gfp);
1936 if (!asoc->ssnmap)
1937 goto clean_up;
1938
1939 retry:
1940 if (unlikely(!idr_pre_get(&sctp_assocs_id, gfp)))
1941 goto clean_up;
1942 spin_lock_bh(&sctp_assocs_id_lock);
1943 error = idr_get_new_above(&sctp_assocs_id, (void *)asoc, 1,
1944 &assoc_id);
1945 spin_unlock_bh(&sctp_assocs_id_lock);
1946 if (error == -EAGAIN)
1947 goto retry;
1948 else if (error)
1949 goto clean_up;
1950
1951 asoc->assoc_id = (sctp_assoc_t) assoc_id;
1952 }
1953
1954 /* ADDIP Section 4.1 ASCONF Chunk Procedures
1955 *
1956 * When an endpoint has an ASCONF signaled change to be sent to the
1957 * remote endpoint it should do the following:
1958 * ...
1959 * A2) A serial number should be assigned to the Chunk. The serial
1960 * number should be a monotonically increasing number. All serial
1961 * numbers are defined to be initialized at the start of the
1962 * association to the same value as the Initial TSN.
1963 */
1964 asoc->peer.addip_serial = asoc->peer.i.initial_tsn - 1;
1965 return 1;
1966
1967clean_up:
1968 /* Release the transport structures. */
1969 list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
1970 transport = list_entry(pos, struct sctp_transport, transports);
1971 list_del_init(pos);
1972 sctp_transport_free(transport);
1973 }
Frank Filz3f7a87d2005-06-20 13:14:57 -07001974
1975 asoc->peer.transport_count = 0;
1976
Linus Torvalds1da177e2005-04-16 15:20:36 -07001977nomem:
1978 return 0;
1979}
1980
1981
1982/* Update asoc with the option described in param.
1983 *
1984 * RFC2960 3.3.2.1 Optional/Variable Length Parameters in INIT
1985 *
1986 * asoc is the association to update.
1987 * param is the variable length parameter to use for update.
1988 * cid tells us if this is an INIT, INIT ACK or COOKIE ECHO.
1989 * If the current packet is an INIT we want to minimize the amount of
1990 * work we do. In particular, we should not build transport
1991 * structures for the addresses.
1992 */
1993static int sctp_process_param(struct sctp_association *asoc,
1994 union sctp_params param,
1995 const union sctp_addr *peer_addr,
Al Virodd0fc662005-10-07 07:46:04 +01001996 gfp_t gfp)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001997{
1998 union sctp_addr addr;
1999 int i;
2000 __u16 sat;
2001 int retval = 1;
2002 sctp_scope_t scope;
2003 time_t stale;
2004 struct sctp_af *af;
2005
2006 /* We maintain all INIT parameters in network byte order all the
2007 * time. This allows us to not worry about whether the parameters
2008 * came from a fresh INIT, and INIT ACK, or were stored in a cookie.
2009 */
2010 switch (param.p->type) {
2011 case SCTP_PARAM_IPV6_ADDRESS:
2012 if (PF_INET6 != asoc->base.sk->sk_family)
2013 break;
2014 /* Fall through. */
2015 case SCTP_PARAM_IPV4_ADDRESS:
2016 af = sctp_get_af_specific(param_type2af(param.p->type));
2017 af->from_addr_param(&addr, param.addr, asoc->peer.port, 0);
2018 scope = sctp_scope(peer_addr);
2019 if (sctp_in_scope(&addr, scope))
Sridhar Samudralaad8fec12006-07-21 14:48:50 -07002020 if (!sctp_assoc_add_peer(asoc, &addr, gfp, SCTP_UNCONFIRMED))
Linus Torvalds1da177e2005-04-16 15:20:36 -07002021 return 0;
2022 break;
2023
2024 case SCTP_PARAM_COOKIE_PRESERVATIVE:
2025 if (!sctp_cookie_preserve_enable)
2026 break;
2027
2028 stale = ntohl(param.life->lifespan_increment);
2029
2030 /* Suggested Cookie Life span increment's unit is msec,
2031 * (1/1000sec).
2032 */
2033 asoc->cookie_life.tv_sec += stale / 1000;
2034 asoc->cookie_life.tv_usec += (stale % 1000) * 1000;
2035 break;
2036
2037 case SCTP_PARAM_HOST_NAME_ADDRESS:
2038 SCTP_DEBUG_PRINTK("unimplemented SCTP_HOST_NAME_ADDRESS\n");
2039 break;
2040
2041 case SCTP_PARAM_SUPPORTED_ADDRESS_TYPES:
2042 /* Turn off the default values first so we'll know which
2043 * ones are really set by the peer.
2044 */
2045 asoc->peer.ipv4_address = 0;
2046 asoc->peer.ipv6_address = 0;
2047
2048 /* Cycle through address types; avoid divide by 0. */
2049 sat = ntohs(param.p->length) - sizeof(sctp_paramhdr_t);
2050 if (sat)
2051 sat /= sizeof(__u16);
2052
2053 for (i = 0; i < sat; ++i) {
2054 switch (param.sat->types[i]) {
2055 case SCTP_PARAM_IPV4_ADDRESS:
2056 asoc->peer.ipv4_address = 1;
2057 break;
2058
2059 case SCTP_PARAM_IPV6_ADDRESS:
2060 asoc->peer.ipv6_address = 1;
2061 break;
2062
2063 case SCTP_PARAM_HOST_NAME_ADDRESS:
2064 asoc->peer.hostname_address = 1;
2065 break;
2066
2067 default: /* Just ignore anything else. */
2068 break;
2069 };
2070 }
2071 break;
2072
2073 case SCTP_PARAM_STATE_COOKIE:
2074 asoc->peer.cookie_len =
2075 ntohs(param.p->length) - sizeof(sctp_paramhdr_t);
2076 asoc->peer.cookie = param.cookie->body;
2077 break;
2078
2079 case SCTP_PARAM_HEARTBEAT_INFO:
2080 /* Would be odd to receive, but it causes no problems. */
2081 break;
2082
2083 case SCTP_PARAM_UNRECOGNIZED_PARAMETERS:
2084 /* Rejected during verify stage. */
2085 break;
2086
2087 case SCTP_PARAM_ECN_CAPABLE:
2088 asoc->peer.ecn_capable = 1;
2089 break;
2090
2091 case SCTP_PARAM_ADAPTION_LAYER_IND:
2092 asoc->peer.adaption_ind = param.aind->adaption_ind;
2093 break;
2094
2095 case SCTP_PARAM_FWD_TSN_SUPPORT:
2096 if (sctp_prsctp_enable) {
2097 asoc->peer.prsctp_capable = 1;
2098 break;
2099 }
2100 /* Fall Through */
2101 default:
2102 /* Any unrecognized parameters should have been caught
2103 * and handled by sctp_verify_param() which should be
2104 * called prior to this routine. Simply log the error
2105 * here.
2106 */
2107 SCTP_DEBUG_PRINTK("Ignoring param: %d for association %p.\n",
2108 ntohs(param.p->type), asoc);
2109 break;
2110 };
2111
2112 return retval;
2113}
2114
2115/* Select a new verification tag. */
2116__u32 sctp_generate_tag(const struct sctp_endpoint *ep)
2117{
2118 /* I believe that this random number generator complies with RFC1750.
2119 * A tag of 0 is reserved for special cases (e.g. INIT).
2120 */
2121 __u32 x;
2122
2123 do {
2124 get_random_bytes(&x, sizeof(__u32));
2125 } while (x == 0);
2126
2127 return x;
2128}
2129
2130/* Select an initial TSN to send during startup. */
2131__u32 sctp_generate_tsn(const struct sctp_endpoint *ep)
2132{
2133 __u32 retval;
2134
2135 get_random_bytes(&retval, sizeof(__u32));
2136 return retval;
2137}
2138
2139/*
2140 * ADDIP 3.1.1 Address Configuration Change Chunk (ASCONF)
2141 * 0 1 2 3
2142 * 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
2143 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2144 * | Type = 0xC1 | Chunk Flags | Chunk Length |
2145 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2146 * | Serial Number |
2147 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2148 * | Address Parameter |
2149 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2150 * | ASCONF Parameter #1 |
2151 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2152 * \ \
2153 * / .... /
2154 * \ \
2155 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2156 * | ASCONF Parameter #N |
2157 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2158 *
2159 * Address Parameter and other parameter will not be wrapped in this function
2160 */
2161static struct sctp_chunk *sctp_make_asconf(struct sctp_association *asoc,
2162 union sctp_addr *addr,
2163 int vparam_len)
2164{
2165 sctp_addiphdr_t asconf;
2166 struct sctp_chunk *retval;
2167 int length = sizeof(asconf) + vparam_len;
2168 union sctp_addr_param addrparam;
2169 int addrlen;
2170 struct sctp_af *af = sctp_get_af_specific(addr->v4.sin_family);
2171
2172 addrlen = af->to_addr_param(addr, &addrparam);
2173 if (!addrlen)
2174 return NULL;
2175 length += addrlen;
2176
2177 /* Create the chunk. */
2178 retval = sctp_make_chunk(asoc, SCTP_CID_ASCONF, 0, length);
2179 if (!retval)
2180 return NULL;
2181
2182 asconf.serial = htonl(asoc->addip_serial++);
2183
2184 retval->subh.addip_hdr =
2185 sctp_addto_chunk(retval, sizeof(asconf), &asconf);
2186 retval->param_hdr.v =
2187 sctp_addto_chunk(retval, addrlen, &addrparam);
2188
2189 return retval;
2190}
2191
2192/* ADDIP
2193 * 3.2.1 Add IP Address
2194 * 0 1 2 3
2195 * 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
2196 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2197 * | Type = 0xC001 | Length = Variable |
2198 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2199 * | ASCONF-Request Correlation ID |
2200 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2201 * | Address Parameter |
2202 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2203 *
2204 * 3.2.2 Delete IP Address
2205 * 0 1 2 3
2206 * 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
2207 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2208 * | Type = 0xC002 | Length = Variable |
2209 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2210 * | ASCONF-Request Correlation ID |
2211 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2212 * | Address Parameter |
2213 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2214 *
2215 */
2216struct sctp_chunk *sctp_make_asconf_update_ip(struct sctp_association *asoc,
2217 union sctp_addr *laddr,
2218 struct sockaddr *addrs,
2219 int addrcnt,
2220 __u16 flags)
2221{
2222 sctp_addip_param_t param;
2223 struct sctp_chunk *retval;
2224 union sctp_addr_param addr_param;
2225 union sctp_addr *addr;
2226 void *addr_buf;
2227 struct sctp_af *af;
2228 int paramlen = sizeof(param);
2229 int addr_param_len = 0;
2230 int totallen = 0;
2231 int i;
2232
2233 /* Get total length of all the address parameters. */
2234 addr_buf = addrs;
2235 for (i = 0; i < addrcnt; i++) {
2236 addr = (union sctp_addr *)addr_buf;
2237 af = sctp_get_af_specific(addr->v4.sin_family);
2238 addr_param_len = af->to_addr_param(addr, &addr_param);
2239
2240 totallen += paramlen;
2241 totallen += addr_param_len;
2242
2243 addr_buf += af->sockaddr_len;
2244 }
2245
2246 /* Create an asconf chunk with the required length. */
2247 retval = sctp_make_asconf(asoc, laddr, totallen);
2248 if (!retval)
2249 return NULL;
2250
2251 /* Add the address parameters to the asconf chunk. */
2252 addr_buf = addrs;
2253 for (i = 0; i < addrcnt; i++) {
2254 addr = (union sctp_addr *)addr_buf;
2255 af = sctp_get_af_specific(addr->v4.sin_family);
2256 addr_param_len = af->to_addr_param(addr, &addr_param);
2257 param.param_hdr.type = flags;
2258 param.param_hdr.length = htons(paramlen + addr_param_len);
2259 param.crr_id = i;
2260
2261 sctp_addto_chunk(retval, paramlen, &param);
2262 sctp_addto_chunk(retval, addr_param_len, &addr_param);
2263
2264 addr_buf += af->sockaddr_len;
2265 }
2266 return retval;
2267}
2268
2269/* ADDIP
2270 * 3.2.4 Set Primary IP Address
2271 * 0 1 2 3
2272 * 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
2273 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2274 * | Type =0xC004 | Length = Variable |
2275 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2276 * | ASCONF-Request Correlation ID |
2277 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2278 * | Address Parameter |
2279 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2280 *
2281 * Create an ASCONF chunk with Set Primary IP address parameter.
2282 */
2283struct sctp_chunk *sctp_make_asconf_set_prim(struct sctp_association *asoc,
2284 union sctp_addr *addr)
2285{
2286 sctp_addip_param_t param;
2287 struct sctp_chunk *retval;
2288 int len = sizeof(param);
2289 union sctp_addr_param addrparam;
2290 int addrlen;
2291 struct sctp_af *af = sctp_get_af_specific(addr->v4.sin_family);
2292
2293 addrlen = af->to_addr_param(addr, &addrparam);
2294 if (!addrlen)
2295 return NULL;
2296 len += addrlen;
2297
2298 /* Create the chunk and make asconf header. */
2299 retval = sctp_make_asconf(asoc, addr, len);
2300 if (!retval)
2301 return NULL;
2302
2303 param.param_hdr.type = SCTP_PARAM_SET_PRIMARY;
2304 param.param_hdr.length = htons(len);
2305 param.crr_id = 0;
2306
2307 sctp_addto_chunk(retval, sizeof(param), &param);
2308 sctp_addto_chunk(retval, addrlen, &addrparam);
2309
2310 return retval;
2311}
2312
2313/* ADDIP 3.1.2 Address Configuration Acknowledgement Chunk (ASCONF-ACK)
2314 * 0 1 2 3
2315 * 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
2316 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2317 * | Type = 0x80 | Chunk Flags | Chunk Length |
2318 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2319 * | Serial Number |
2320 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2321 * | ASCONF Parameter Response#1 |
2322 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2323 * \ \
2324 * / .... /
2325 * \ \
2326 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2327 * | ASCONF Parameter Response#N |
2328 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2329 *
2330 * Create an ASCONF_ACK chunk with enough space for the parameter responses.
2331 */
2332static struct sctp_chunk *sctp_make_asconf_ack(const struct sctp_association *asoc,
2333 __u32 serial, int vparam_len)
2334{
2335 sctp_addiphdr_t asconf;
2336 struct sctp_chunk *retval;
2337 int length = sizeof(asconf) + vparam_len;
2338
2339 /* Create the chunk. */
2340 retval = sctp_make_chunk(asoc, SCTP_CID_ASCONF_ACK, 0, length);
2341 if (!retval)
2342 return NULL;
2343
2344 asconf.serial = htonl(serial);
2345
2346 retval->subh.addip_hdr =
2347 sctp_addto_chunk(retval, sizeof(asconf), &asconf);
2348
2349 return retval;
2350}
2351
2352/* Add response parameters to an ASCONF_ACK chunk. */
2353static void sctp_add_asconf_response(struct sctp_chunk *chunk, __u32 crr_id,
2354 __u16 err_code, sctp_addip_param_t *asconf_param)
2355{
2356 sctp_addip_param_t ack_param;
2357 sctp_errhdr_t err_param;
2358 int asconf_param_len = 0;
2359 int err_param_len = 0;
2360 __u16 response_type;
2361
2362 if (SCTP_ERROR_NO_ERROR == err_code) {
2363 response_type = SCTP_PARAM_SUCCESS_REPORT;
2364 } else {
2365 response_type = SCTP_PARAM_ERR_CAUSE;
2366 err_param_len = sizeof(err_param);
2367 if (asconf_param)
2368 asconf_param_len =
2369 ntohs(asconf_param->param_hdr.length);
2370 }
2371
2372 /* Add Success Indication or Error Cause Indication parameter. */
2373 ack_param.param_hdr.type = response_type;
2374 ack_param.param_hdr.length = htons(sizeof(ack_param) +
2375 err_param_len +
2376 asconf_param_len);
2377 ack_param.crr_id = crr_id;
2378 sctp_addto_chunk(chunk, sizeof(ack_param), &ack_param);
2379
2380 if (SCTP_ERROR_NO_ERROR == err_code)
2381 return;
2382
2383 /* Add Error Cause parameter. */
2384 err_param.cause = err_code;
2385 err_param.length = htons(err_param_len + asconf_param_len);
2386 sctp_addto_chunk(chunk, err_param_len, &err_param);
2387
2388 /* Add the failed TLV copied from ASCONF chunk. */
2389 if (asconf_param)
2390 sctp_addto_chunk(chunk, asconf_param_len, asconf_param);
2391}
2392
2393/* Process a asconf parameter. */
2394static __u16 sctp_process_asconf_param(struct sctp_association *asoc,
2395 struct sctp_chunk *asconf,
2396 sctp_addip_param_t *asconf_param)
2397{
2398 struct sctp_transport *peer;
2399 struct sctp_af *af;
2400 union sctp_addr addr;
2401 struct list_head *pos;
2402 union sctp_addr_param *addr_param;
2403
2404 addr_param = (union sctp_addr_param *)
2405 ((void *)asconf_param + sizeof(sctp_addip_param_t));
2406
2407 af = sctp_get_af_specific(param_type2af(addr_param->v4.param_hdr.type));
2408 if (unlikely(!af))
2409 return SCTP_ERROR_INV_PARAM;
2410
2411 af->from_addr_param(&addr, addr_param, asoc->peer.port, 0);
2412 switch (asconf_param->param_hdr.type) {
2413 case SCTP_PARAM_ADD_IP:
2414 /* ADDIP 4.3 D9) If an endpoint receives an ADD IP address
2415 * request and does not have the local resources to add this
2416 * new address to the association, it MUST return an Error
2417 * Cause TLV set to the new error code 'Operation Refused
2418 * Due to Resource Shortage'.
2419 */
2420
Sridhar Samudralaad8fec12006-07-21 14:48:50 -07002421 peer = sctp_assoc_add_peer(asoc, &addr, GFP_ATOMIC, SCTP_UNCONFIRMED);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002422 if (!peer)
2423 return SCTP_ERROR_RSRC_LOW;
2424
2425 /* Start the heartbeat timer. */
2426 if (!mod_timer(&peer->hb_timer, sctp_transport_timeout(peer)))
2427 sctp_transport_hold(peer);
2428 break;
2429 case SCTP_PARAM_DEL_IP:
2430 /* ADDIP 4.3 D7) If a request is received to delete the
2431 * last remaining IP address of a peer endpoint, the receiver
2432 * MUST send an Error Cause TLV with the error cause set to the
2433 * new error code 'Request to Delete Last Remaining IP Address'.
2434 */
2435 pos = asoc->peer.transport_addr_list.next;
2436 if (pos->next == &asoc->peer.transport_addr_list)
2437 return SCTP_ERROR_DEL_LAST_IP;
2438
2439 /* ADDIP 4.3 D8) If a request is received to delete an IP
2440 * address which is also the source address of the IP packet
2441 * which contained the ASCONF chunk, the receiver MUST reject
2442 * this request. To reject the request the receiver MUST send
2443 * an Error Cause TLV set to the new error code 'Request to
2444 * Delete Source IP Address'
2445 */
2446 if (sctp_cmp_addr_exact(sctp_source(asconf), &addr))
2447 return SCTP_ERROR_DEL_SRC_IP;
2448
2449 sctp_assoc_del_peer(asoc, &addr);
2450 break;
2451 case SCTP_PARAM_SET_PRIMARY:
2452 peer = sctp_assoc_lookup_paddr(asoc, &addr);
2453 if (!peer)
2454 return SCTP_ERROR_INV_PARAM;
2455
2456 sctp_assoc_set_primary(asoc, peer);
2457 break;
2458 default:
2459 return SCTP_ERROR_INV_PARAM;
2460 break;
2461 }
2462
2463 return SCTP_ERROR_NO_ERROR;
2464}
2465
2466/* Process an incoming ASCONF chunk with the next expected serial no. and
2467 * return an ASCONF_ACK chunk to be sent in response.
2468 */
2469struct sctp_chunk *sctp_process_asconf(struct sctp_association *asoc,
2470 struct sctp_chunk *asconf)
2471{
2472 sctp_addiphdr_t *hdr;
2473 union sctp_addr_param *addr_param;
2474 sctp_addip_param_t *asconf_param;
2475 struct sctp_chunk *asconf_ack;
2476
2477 __u16 err_code;
2478 int length = 0;
2479 int chunk_len = asconf->skb->len;
2480 __u32 serial;
2481 int all_param_pass = 1;
2482
2483 hdr = (sctp_addiphdr_t *)asconf->skb->data;
2484 serial = ntohl(hdr->serial);
2485
2486 /* Skip the addiphdr and store a pointer to address parameter. */
2487 length = sizeof(sctp_addiphdr_t);
2488 addr_param = (union sctp_addr_param *)(asconf->skb->data + length);
2489 chunk_len -= length;
2490
2491 /* Skip the address parameter and store a pointer to the first
2492 * asconf paramter.
2493 */
2494 length = ntohs(addr_param->v4.param_hdr.length);
2495 asconf_param = (sctp_addip_param_t *)((void *)addr_param + length);
2496 chunk_len -= length;
2497
2498 /* create an ASCONF_ACK chunk.
2499 * Based on the definitions of parameters, we know that the size of
2500 * ASCONF_ACK parameters are less than or equal to the twice of ASCONF
2501 * paramters.
2502 */
2503 asconf_ack = sctp_make_asconf_ack(asoc, serial, chunk_len * 2);
2504 if (!asconf_ack)
2505 goto done;
2506
2507 /* Process the TLVs contained within the ASCONF chunk. */
2508 while (chunk_len > 0) {
2509 err_code = sctp_process_asconf_param(asoc, asconf,
2510 asconf_param);
2511 /* ADDIP 4.1 A7)
2512 * If an error response is received for a TLV parameter,
2513 * all TLVs with no response before the failed TLV are
2514 * considered successful if not reported. All TLVs after
2515 * the failed response are considered unsuccessful unless
2516 * a specific success indication is present for the parameter.
2517 */
2518 if (SCTP_ERROR_NO_ERROR != err_code)
2519 all_param_pass = 0;
2520
2521 if (!all_param_pass)
2522 sctp_add_asconf_response(asconf_ack,
2523 asconf_param->crr_id, err_code,
2524 asconf_param);
2525
2526 /* ADDIP 4.3 D11) When an endpoint receiving an ASCONF to add
2527 * an IP address sends an 'Out of Resource' in its response, it
2528 * MUST also fail any subsequent add or delete requests bundled
2529 * in the ASCONF.
2530 */
2531 if (SCTP_ERROR_RSRC_LOW == err_code)
2532 goto done;
2533
2534 /* Move to the next ASCONF param. */
2535 length = ntohs(asconf_param->param_hdr.length);
2536 asconf_param = (sctp_addip_param_t *)((void *)asconf_param +
2537 length);
2538 chunk_len -= length;
2539 }
2540
2541done:
2542 asoc->peer.addip_serial++;
2543
2544 /* If we are sending a new ASCONF_ACK hold a reference to it in assoc
2545 * after freeing the reference to old asconf ack if any.
2546 */
2547 if (asconf_ack) {
2548 if (asoc->addip_last_asconf_ack)
2549 sctp_chunk_free(asoc->addip_last_asconf_ack);
2550
2551 sctp_chunk_hold(asconf_ack);
2552 asoc->addip_last_asconf_ack = asconf_ack;
2553 }
2554
2555 return asconf_ack;
2556}
2557
2558/* Process a asconf parameter that is successfully acked. */
2559static int sctp_asconf_param_success(struct sctp_association *asoc,
2560 sctp_addip_param_t *asconf_param)
2561{
2562 struct sctp_af *af;
2563 union sctp_addr addr;
2564 struct sctp_bind_addr *bp = &asoc->base.bind_addr;
2565 union sctp_addr_param *addr_param;
2566 struct list_head *pos;
2567 struct sctp_transport *transport;
Sridhar Samudraladc022a92006-07-21 14:49:25 -07002568 struct sctp_sockaddr_entry *saddr;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002569 int retval = 0;
2570
2571 addr_param = (union sctp_addr_param *)
2572 ((void *)asconf_param + sizeof(sctp_addip_param_t));
2573
2574 /* We have checked the packet before, so we do not check again. */
2575 af = sctp_get_af_specific(param_type2af(addr_param->v4.param_hdr.type));
2576 af->from_addr_param(&addr, addr_param, bp->port, 0);
2577
2578 switch (asconf_param->param_hdr.type) {
2579 case SCTP_PARAM_ADD_IP:
2580 sctp_local_bh_disable();
2581 sctp_write_lock(&asoc->base.addr_lock);
Sridhar Samudraladc022a92006-07-21 14:49:25 -07002582 list_for_each(pos, &bp->address_list) {
2583 saddr = list_entry(pos, struct sctp_sockaddr_entry, list);
2584 if (sctp_cmp_addr_exact(&saddr->a, &addr))
2585 saddr->use_as_src = 1;
2586 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07002587 sctp_write_unlock(&asoc->base.addr_lock);
2588 sctp_local_bh_enable();
2589 break;
2590 case SCTP_PARAM_DEL_IP:
2591 sctp_local_bh_disable();
2592 sctp_write_lock(&asoc->base.addr_lock);
2593 retval = sctp_del_bind_addr(bp, &addr);
2594 sctp_write_unlock(&asoc->base.addr_lock);
2595 sctp_local_bh_enable();
2596 list_for_each(pos, &asoc->peer.transport_addr_list) {
2597 transport = list_entry(pos, struct sctp_transport,
2598 transports);
Sridhar Samudraladc022a92006-07-21 14:49:25 -07002599 dst_release(transport->dst);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002600 sctp_transport_route(transport, NULL,
2601 sctp_sk(asoc->base.sk));
2602 }
2603 break;
2604 default:
2605 break;
2606 }
2607
2608 return retval;
2609}
2610
2611/* Get the corresponding ASCONF response error code from the ASCONF_ACK chunk
2612 * for the given asconf parameter. If there is no response for this parameter,
2613 * return the error code based on the third argument 'no_err'.
2614 * ADDIP 4.1
2615 * A7) If an error response is received for a TLV parameter, all TLVs with no
2616 * response before the failed TLV are considered successful if not reported.
2617 * All TLVs after the failed response are considered unsuccessful unless a
2618 * specific success indication is present for the parameter.
2619 */
2620static __u16 sctp_get_asconf_response(struct sctp_chunk *asconf_ack,
2621 sctp_addip_param_t *asconf_param,
2622 int no_err)
2623{
2624 sctp_addip_param_t *asconf_ack_param;
2625 sctp_errhdr_t *err_param;
2626 int length;
2627 int asconf_ack_len = asconf_ack->skb->len;
2628 __u16 err_code;
2629
2630 if (no_err)
2631 err_code = SCTP_ERROR_NO_ERROR;
2632 else
2633 err_code = SCTP_ERROR_REQ_REFUSED;
2634
2635 /* Skip the addiphdr from the asconf_ack chunk and store a pointer to
2636 * the first asconf_ack parameter.
2637 */
2638 length = sizeof(sctp_addiphdr_t);
2639 asconf_ack_param = (sctp_addip_param_t *)(asconf_ack->skb->data +
2640 length);
2641 asconf_ack_len -= length;
2642
2643 while (asconf_ack_len > 0) {
2644 if (asconf_ack_param->crr_id == asconf_param->crr_id) {
2645 switch(asconf_ack_param->param_hdr.type) {
2646 case SCTP_PARAM_SUCCESS_REPORT:
2647 return SCTP_ERROR_NO_ERROR;
2648 case SCTP_PARAM_ERR_CAUSE:
2649 length = sizeof(sctp_addip_param_t);
2650 err_param = (sctp_errhdr_t *)
2651 ((void *)asconf_ack_param + length);
2652 asconf_ack_len -= length;
2653 if (asconf_ack_len > 0)
2654 return err_param->cause;
2655 else
2656 return SCTP_ERROR_INV_PARAM;
2657 break;
2658 default:
2659 return SCTP_ERROR_INV_PARAM;
2660 }
2661 }
2662
2663 length = ntohs(asconf_ack_param->param_hdr.length);
2664 asconf_ack_param = (sctp_addip_param_t *)
2665 ((void *)asconf_ack_param + length);
2666 asconf_ack_len -= length;
2667 }
2668
2669 return err_code;
2670}
2671
2672/* Process an incoming ASCONF_ACK chunk against the cached last ASCONF chunk. */
2673int sctp_process_asconf_ack(struct sctp_association *asoc,
2674 struct sctp_chunk *asconf_ack)
2675{
2676 struct sctp_chunk *asconf = asoc->addip_last_asconf;
2677 union sctp_addr_param *addr_param;
2678 sctp_addip_param_t *asconf_param;
2679 int length = 0;
2680 int asconf_len = asconf->skb->len;
2681 int all_param_pass = 0;
2682 int no_err = 1;
2683 int retval = 0;
2684 __u16 err_code = SCTP_ERROR_NO_ERROR;
2685
2686 /* Skip the chunkhdr and addiphdr from the last asconf sent and store
2687 * a pointer to address parameter.
2688 */
2689 length = sizeof(sctp_addip_chunk_t);
2690 addr_param = (union sctp_addr_param *)(asconf->skb->data + length);
2691 asconf_len -= length;
2692
2693 /* Skip the address parameter in the last asconf sent and store a
2694 * pointer to the first asconf paramter.
2695 */
2696 length = ntohs(addr_param->v4.param_hdr.length);
2697 asconf_param = (sctp_addip_param_t *)((void *)addr_param + length);
2698 asconf_len -= length;
2699
2700 /* ADDIP 4.1
2701 * A8) If there is no response(s) to specific TLV parameter(s), and no
2702 * failures are indicated, then all request(s) are considered
2703 * successful.
2704 */
2705 if (asconf_ack->skb->len == sizeof(sctp_addiphdr_t))
2706 all_param_pass = 1;
2707
2708 /* Process the TLVs contained in the last sent ASCONF chunk. */
2709 while (asconf_len > 0) {
2710 if (all_param_pass)
2711 err_code = SCTP_ERROR_NO_ERROR;
2712 else {
2713 err_code = sctp_get_asconf_response(asconf_ack,
2714 asconf_param,
2715 no_err);
2716 if (no_err && (SCTP_ERROR_NO_ERROR != err_code))
2717 no_err = 0;
2718 }
2719
2720 switch (err_code) {
2721 case SCTP_ERROR_NO_ERROR:
2722 retval = sctp_asconf_param_success(asoc, asconf_param);
2723 break;
2724
2725 case SCTP_ERROR_RSRC_LOW:
2726 retval = 1;
2727 break;
2728
2729 case SCTP_ERROR_INV_PARAM:
2730 /* Disable sending this type of asconf parameter in
2731 * future.
2732 */
2733 asoc->peer.addip_disabled_mask |=
2734 asconf_param->param_hdr.type;
2735 break;
2736
2737 case SCTP_ERROR_REQ_REFUSED:
2738 case SCTP_ERROR_DEL_LAST_IP:
2739 case SCTP_ERROR_DEL_SRC_IP:
2740 default:
2741 break;
2742 }
2743
2744 /* Skip the processed asconf parameter and move to the next
2745 * one.
2746 */
2747 length = ntohs(asconf_param->param_hdr.length);
2748 asconf_param = (sctp_addip_param_t *)((void *)asconf_param +
2749 length);
2750 asconf_len -= length;
2751 }
2752
2753 /* Free the cached last sent asconf chunk. */
2754 sctp_chunk_free(asconf);
2755 asoc->addip_last_asconf = NULL;
2756
2757 /* Send the next asconf chunk from the addip chunk queue. */
David S. Miller79af02c2005-07-08 21:47:49 -07002758 if (!list_empty(&asoc->addip_chunk_list)) {
2759 struct list_head *entry = asoc->addip_chunk_list.next;
2760 asconf = list_entry(entry, struct sctp_chunk, list);
2761
2762 list_del_init(entry);
2763
Linus Torvalds1da177e2005-04-16 15:20:36 -07002764 /* Hold the chunk until an ASCONF_ACK is received. */
2765 sctp_chunk_hold(asconf);
2766 if (sctp_primitive_ASCONF(asoc, asconf))
2767 sctp_chunk_free(asconf);
2768 else
2769 asoc->addip_last_asconf = asconf;
2770 }
2771
2772 return retval;
2773}
2774
2775/* Make a FWD TSN chunk. */
2776struct sctp_chunk *sctp_make_fwdtsn(const struct sctp_association *asoc,
2777 __u32 new_cum_tsn, size_t nstreams,
2778 struct sctp_fwdtsn_skip *skiplist)
2779{
2780 struct sctp_chunk *retval = NULL;
2781 struct sctp_fwdtsn_chunk *ftsn_chunk;
2782 struct sctp_fwdtsn_hdr ftsn_hdr;
2783 struct sctp_fwdtsn_skip skip;
2784 size_t hint;
2785 int i;
2786
2787 hint = (nstreams + 1) * sizeof(__u32);
2788
Linus Torvalds1da177e2005-04-16 15:20:36 -07002789 retval = sctp_make_chunk(asoc, SCTP_CID_FWD_TSN, 0, hint);
2790
2791 if (!retval)
2792 return NULL;
2793
2794 ftsn_chunk = (struct sctp_fwdtsn_chunk *)retval->subh.fwdtsn_hdr;
2795
2796 ftsn_hdr.new_cum_tsn = htonl(new_cum_tsn);
2797 retval->subh.fwdtsn_hdr =
2798 sctp_addto_chunk(retval, sizeof(ftsn_hdr), &ftsn_hdr);
2799
2800 for (i = 0; i < nstreams; i++) {
2801 skip.stream = skiplist[i].stream;
2802 skip.ssn = skiplist[i].ssn;
2803 sctp_addto_chunk(retval, sizeof(skip), &skip);
2804 }
2805
2806 return retval;
2807}