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[deliverable/linux.git] / net / sctp / sm_make_chunk.c
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1da177e4
LT		 1/* SCTP kernel reference Implementation
2 * (C) Copyright IBM Corp. 2001, 2004
3 * Copyright (c) 1999-2000 Cisco, Inc.
4 * Copyright (c) 1999-2001 Motorola, Inc.
5 * Copyright (c) 2001-2002 Intel Corp.
6 *
7 * This file is part of the SCTP kernel reference Implementation
8 *
9 * These functions work with the state functions in sctp_sm_statefuns.c
10 * to implement the state operations. These functions implement the
11 * steps which require modifying existing data structures.
12 *
13 * The SCTP reference implementation is free software;
14 * you can redistribute it and/or modify it under the terms of
15 * the GNU General Public License as published by
16 * the Free Software Foundation; either version 2, or (at your option)
17 * any later version.
18 *
19 * The SCTP reference implementation is distributed in the hope that it
20 * will be useful, but WITHOUT ANY WARRANTY; without even the implied
21 * ************************
22 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
23 * See the GNU General Public License for more details.
24 *
25 * You should have received a copy of the GNU General Public License
26 * along with GNU CC; see the file COPYING. If not, write to
27 * the Free Software Foundation, 59 Temple Place - Suite 330,
28 * Boston, MA 02111-1307, USA.
29 *
30 * Please send any bug reports or fixes you make to the
31 * email address(es):
32 * lksctp developers <lksctp-developers@lists.sourceforge.net>
33 *
34 * Or submit a bug report through the following website:
35 * http://www.sf.net/projects/lksctp
36 *
37 * Written or modified by:
38 * La Monte H.P. Yarroll <piggy@acm.org>
39 * Karl Knutson <karl@athena.chicago.il.us>
40 * C. Robin <chris@hundredacre.ac.uk>
41 * Jon Grimm <jgrimm@us.ibm.com>
42 * Xingang Guo <xingang.guo@intel.com>
43 * Dajiang Zhang <dajiang.zhang@nokia.com>
44 * Sridhar Samudrala <sri@us.ibm.com>
45 * Daisy Chang <daisyc@us.ibm.com>
46 * Ardelle Fan <ardelle.fan@intel.com>
47 * Kevin Gao <kevin.gao@intel.com>
48 *
49 * Any bugs reported given to us we will try to fix... any fixes shared will
50 * be incorporated into the next SCTP release.
51 */
52
53#include <linux/types.h>
54#include <linux/kernel.h>
55#include <linux/ip.h>
56#include <linux/ipv6.h>
57#include <linux/net.h>
58#include <linux/inet.h>
59#include <asm/scatterlist.h>
60#include <linux/crypto.h>
61#include <net/sock.h>
62
63#include <linux/skbuff.h>
64#include <linux/random.h> /* for get_random_bytes */
65#include <net/sctp/sctp.h>
66#include <net/sctp/sm.h>
67
e18b890b 68extern struct kmem_cache *sctp_chunk_cachep;
1da177e4
LT		 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,
dd0fc66f 81 gfp_t gfp);
1da177e4
LT		 82
83/* What was the inbound interface for this chunk? */
84int sctp_chunk_iif(const struct sctp_chunk *chunk)
85{
86 struct sctp_af *af;
87 int iif = 0;
88
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 */
5bf2db03 114void sctp_init_cause(struct sctp_chunk *chunk, __be16 cause_code,
1da177e4
LT		 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;
4a1c0107
VY		 127 chunk->subh.err_hdr = sctp_addto_chunk(chunk, sizeof(sctp_errhdr_t), &err);
128 sctp_addto_chunk(chunk, paylen, payload);
1da177e4
LT		 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,
dd0fc66f 177 gfp_t gfp, int vparam_len)
1da177e4
LT		 178{
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;
3dbe8656 186 __be16 types[2];
0f3fffd8 187 sctp_adaptation_ind_param_t aiparam;
1da177e4
LT		 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);
0f3fffd8 252 aiparam.param_hdr.type = SCTP_PARAM_ADAPTATION_LAYER_IND;
1da177e4 253 aiparam.param_hdr.length = htons(sizeof(aiparam));
0f3fffd8 254 aiparam.adaptation_ind = htonl(sp->adaptation_ind);
1da177e4
LT		 255 sctp_addto_chunk(retval, sizeof(aiparam), &aiparam);
256nodata:
a51482bd 257 kfree(addrs.v);
1da177e4
LT		 258 return retval;
259}
260
261struct sctp_chunk *sctp_make_init_ack(const struct sctp_association *asoc,
262 const struct sctp_chunk *chunk,
dd0fc66f 263 gfp_t gfp, int unkparam_len)
1da177e4
LT		 264{
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;
0f3fffd8 272 sctp_adaptation_ind_param_t aiparam;
1da177e4
LT		 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
0f3fffd8 326 aiparam.param_hdr.type = SCTP_PARAM_ADAPTATION_LAYER_IND;
1da177e4 327 aiparam.param_hdr.length = htons(sizeof(aiparam));
0f3fffd8 328 aiparam.adaptation_ind = htonl(sctp_sk(asoc->base.sk)->adaptation_ind);
1da177e4
LT		 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:
a51482bd 349 kfree(addrs.v);
1da177e4
LT		 350 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. */
eaa5c54d 555 if (sinfo->sinfo_flags & SCTP_UNORDERED) {
1da177e4
LT		 556 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
047a2428
JF		 711 /* Set the T-bit if we have no association (vtag will be
712 * reflected)
713 */
1da177e4
LT		 714 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
047a2428 735 * association, except when responding to an INIT (sctpimpguide 2.41).
1da177e4
LT		 736 */
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
047a2428
JF		 744 /* 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 }
1da177e4
LT		 754
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;
9f81bcd9 778 __be32 payload;
1da177e4
LT		 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,
c164a9ba
SS		 809 const struct msghdr *msg,
810 size_t paylen)
1da177e4
LT		 811{
812 struct sctp_chunk *retval;
c164a9ba
SS		 813 void *payload = NULL;
814 int err;
1da177e4 815
c164a9ba 816 retval = sctp_make_abort(asoc, NULL, sizeof(sctp_errhdr_t) + paylen);
1da177e4
LT		 817 if (!retval)
818 goto err_chunk;
819
820 if (paylen) {
821 /* Put the msg_iov together into payload. */
c164a9ba 822 payload = kmalloc(paylen, GFP_KERNEL);
1da177e4
LT		 823 if (!payload)
824 goto err_payload;
c164a9ba
SS		 825
826 err = memcpy_fromiovec(payload, msg->msg_iov, paylen);
827 if (err < 0)
828 goto err_copy;
1da177e4
LT		 829 }
830
831 sctp_init_cause(retval, SCTP_ERROR_USER_ABORT, payload, paylen);
832
833 if (paylen)
834 kfree(payload);
835
836 return retval;
837
838err_copy:
839 kfree(payload);
840err_payload:
841 sctp_chunk_free(retval);
842 retval = NULL;
843err_chunk:
844 return retval;
845}
846
847/* Make an ABORT chunk with a PROTOCOL VIOLATION cause code. */
848struct sctp_chunk *sctp_make_abort_violation(
849 const struct sctp_association *asoc,
850 const struct sctp_chunk *chunk,
851 const __u8 *payload,
852 const size_t paylen)
853{
854 struct sctp_chunk *retval;
855 struct sctp_paramhdr phdr;
856
857 retval = sctp_make_abort(asoc, chunk, sizeof(sctp_errhdr_t) + paylen
858 + sizeof(sctp_chunkhdr_t));
859 if (!retval)
860 goto end;
861
862 sctp_init_cause(retval, SCTP_ERROR_PROTO_VIOLATION, payload, paylen);
863
864 phdr.type = htons(chunk->chunk_hdr->type);
865 phdr.length = chunk->chunk_hdr->length;
866 sctp_addto_chunk(retval, sizeof(sctp_paramhdr_t), &phdr);
867
868end:
869 return retval;
870}
871
872/* Make a HEARTBEAT chunk. */
873struct sctp_chunk *sctp_make_heartbeat(const struct sctp_association *asoc,
874 const struct sctp_transport *transport,
875 const void *payload, const size_t paylen)
876{
877 struct sctp_chunk *retval = sctp_make_chunk(asoc, SCTP_CID_HEARTBEAT,
878 0, paylen);
879
880 if (!retval)
881 goto nodata;
882
883 /* Cast away the 'const', as this is just telling the chunk
884 * what transport it belongs to.
885 */
886 retval->transport = (struct sctp_transport *) transport;
887 retval->subh.hbs_hdr = sctp_addto_chunk(retval, paylen, payload);
888
889nodata:
890 return retval;
891}
892
893struct sctp_chunk *sctp_make_heartbeat_ack(const struct sctp_association *asoc,
894 const struct sctp_chunk *chunk,
895 const void *payload, const size_t paylen)
896{
897 struct sctp_chunk *retval;
898
899 retval = sctp_make_chunk(asoc, SCTP_CID_HEARTBEAT_ACK, 0, paylen);
900 if (!retval)
901 goto nodata;
902
903 retval->subh.hbs_hdr = sctp_addto_chunk(retval, paylen, payload);
904
905 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
906 *
907 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
908 * HEARTBEAT ACK, * etc.) to the same destination transport
909 * address from which it * received the DATA or control chunk
910 * to which it is replying.
911 *
912 * [HBACK back to where the HEARTBEAT came from.]
913 */
914 if (chunk)
915 retval->transport = chunk->transport;
916
917nodata:
918 return retval;
919}
920
921/* Create an Operation Error chunk with the specified space reserved.
922 * This routine can be used for containing multiple causes in the chunk.
923 */
924static struct sctp_chunk *sctp_make_op_error_space(
925 const struct sctp_association *asoc,
926 const struct sctp_chunk *chunk,
927 size_t size)
928{
929 struct sctp_chunk *retval;
930
931 retval = sctp_make_chunk(asoc, SCTP_CID_ERROR, 0,
932 sizeof(sctp_errhdr_t) + size);
933 if (!retval)
934 goto nodata;
935
936 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
937 *
938 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
939 * HEARTBEAT ACK, etc.) to the same destination transport
940 * address from which it received the DATA or control chunk
941 * to which it is replying.
942 *
943 */
944 if (chunk)
945 retval->transport = chunk->transport;
946
947nodata:
948 return retval;
949}
950
951/* Create an Operation Error chunk. */
952struct sctp_chunk *sctp_make_op_error(const struct sctp_association *asoc,
953 const struct sctp_chunk *chunk,
63706c5c 954 __be16 cause_code, const void *payload,
1da177e4
LT		 955 size_t paylen)
956{
957 struct sctp_chunk *retval;
958
959 retval = sctp_make_op_error_space(asoc, chunk, paylen);
960 if (!retval)
961 goto nodata;
962
963 sctp_init_cause(retval, cause_code, payload, paylen);
964
965nodata:
966 return retval;
967}
968
969/********************************************************************
970 * 2nd Level Abstractions
971 ********************************************************************/
972
973/* Turn an skb into a chunk.
974 * FIXME: Eventually move the structure directly inside the skb->cb[].
975 */
976struct sctp_chunk *sctp_chunkify(struct sk_buff *skb,
977 const struct sctp_association *asoc,
978 struct sock *sk)
979{
980 struct sctp_chunk *retval;
981
54e6ecb2 982 retval = kmem_cache_alloc(sctp_chunk_cachep, GFP_ATOMIC);
1da177e4
LT		 983
984 if (!retval)
985 goto nodata;
986 memset(retval, 0, sizeof(struct sctp_chunk));
987
988 if (!sk) {
989 SCTP_DEBUG_PRINTK("chunkifying skb %p w/o an sk\n", skb);
990 }
991
79af02c2 992 INIT_LIST_HEAD(&retval->list);
1da177e4
LT		 993 retval->skb = skb;
994 retval->asoc = (struct sctp_association *)asoc;
995 retval->resent = 0;
996 retval->has_tsn = 0;
997 retval->has_ssn = 0;
998 retval->rtt_in_progress = 0;
999 retval->sent_at = 0;
1000 retval->singleton = 1;
1001 retval->end_of_packet = 0;
1002 retval->ecn_ce_done = 0;
1003 retval->pdiscard = 0;
1004
1005 /* sctpimpguide-05.txt Section 2.8.2
1006 * M1) Each time a new DATA chunk is transmitted
1007 * set the 'TSN.Missing.Report' count for that TSN to 0. The
1008 * 'TSN.Missing.Report' count will be used to determine missing chunks
1009 * and when to fast retransmit.
1010 */
1011 retval->tsn_missing_report = 0;
1012 retval->tsn_gap_acked = 0;
1013 retval->fast_retransmit = 0;
1014
1015 /* If this is a fragmented message, track all fragments
1016 * of the message (for SEND_FAILED).
1017 */
1018 retval->msg = NULL;
1019
1020 /* Polish the bead hole. */
1021 INIT_LIST_HEAD(&retval->transmitted_list);
1022 INIT_LIST_HEAD(&retval->frag_list);
1023 SCTP_DBG_OBJCNT_INC(chunk);
1024 atomic_set(&retval->refcnt, 1);
1025
1026nodata:
1027 return retval;
1028}
1029
1030/* Set chunk->source and dest based on the IP header in chunk->skb. */
1031void sctp_init_addrs(struct sctp_chunk *chunk, union sctp_addr *src,
1032 union sctp_addr *dest)
1033{
f235fca3 1034 memcpy(&chunk->source, src, sizeof(union sctp_addr));
16b0a030 1035 memcpy(&chunk->dest, dest, sizeof(union sctp_addr));
1da177e4
LT		 1036}
1037
1038/* Extract the source address from a chunk. */
1039const union sctp_addr *sctp_source(const struct sctp_chunk *chunk)
1040{
1041 /* If we have a known transport, use that. */
1042 if (chunk->transport) {
6a1e5f33 1043 return &chunk->transport->ipaddr;
1da177e4
LT		 1044 } else {
1045 /* Otherwise, extract it from the IP header. */
6a1e5f33 1046 return &chunk->source;
1da177e4
LT		 1047 }
1048}
1049
1050/* Create a new chunk, setting the type and flags headers from the
1051 * arguments, reserving enough space for a 'paylen' byte payload.
1052 */
1053SCTP_STATIC
1054struct sctp_chunk *sctp_make_chunk(const struct sctp_association *asoc,
1055 __u8 type, __u8 flags, int paylen)
1056{
1057 struct sctp_chunk *retval;
1058 sctp_chunkhdr_t *chunk_hdr;
1059 struct sk_buff *skb;
1060 struct sock *sk;
1061
1062 /* No need to allocate LL here, as this is only a chunk. */
1063 skb = alloc_skb(WORD_ROUND(sizeof(sctp_chunkhdr_t) + paylen),
1064 GFP_ATOMIC);
1065 if (!skb)
1066 goto nodata;
1067
1068 /* Make room for the chunk header. */
1069 chunk_hdr = (sctp_chunkhdr_t *)skb_put(skb, sizeof(sctp_chunkhdr_t));
1070 chunk_hdr->type = type;
1071 chunk_hdr->flags = flags;
1072 chunk_hdr->length = htons(sizeof(sctp_chunkhdr_t));
1073
1074 sk = asoc ? asoc->base.sk : NULL;
1075 retval = sctp_chunkify(skb, asoc, sk);
1076 if (!retval) {
1077 kfree_skb(skb);
1078 goto nodata;
1079 }
1080
1081 retval->chunk_hdr = chunk_hdr;
1082 retval->chunk_end = ((__u8 *)chunk_hdr) + sizeof(struct sctp_chunkhdr);
1083
1084 /* Set the skb to the belonging sock for accounting. */
1085 skb->sk = sk;
1086
1087 return retval;
1088nodata:
1089 return NULL;
1090}
1091
1092
1093/* Release the memory occupied by a chunk. */
1094static void sctp_chunk_destroy(struct sctp_chunk *chunk)
1095{
1096 /* Free the chunk skb data and the SCTP_chunk stub itself. */
1097 dev_kfree_skb(chunk->skb);
1098
1099 SCTP_DBG_OBJCNT_DEC(chunk);
1100 kmem_cache_free(sctp_chunk_cachep, chunk);
1101}
1102
1103/* Possibly, free the chunk. */
1104void sctp_chunk_free(struct sctp_chunk *chunk)
1105{
79af02c2 1106 BUG_ON(!list_empty(&chunk->list));
1da177e4
LT		 1107 list_del_init(&chunk->transmitted_list);
1108
1109 /* Release our reference on the message tracker. */
1110 if (chunk->msg)
1111 sctp_datamsg_put(chunk->msg);
1112
1113 sctp_chunk_put(chunk);
1114}
1115
1116/* Grab a reference to the chunk. */
1117void sctp_chunk_hold(struct sctp_chunk *ch)
1118{
1119 atomic_inc(&ch->refcnt);
1120}
1121
1122/* Release a reference to the chunk. */
1123void sctp_chunk_put(struct sctp_chunk *ch)
1124{
1125 if (atomic_dec_and_test(&ch->refcnt))
1126 sctp_chunk_destroy(ch);
1127}
1128
1129/* Append bytes to the end of a chunk. Will panic if chunk is not big
1130 * enough.
1131 */
1132void *sctp_addto_chunk(struct sctp_chunk *chunk, int len, const void *data)
1133{
1134 void *target;
1135 void *padding;
1136 int chunklen = ntohs(chunk->chunk_hdr->length);
1137 int padlen = chunklen % 4;
1138
1139 padding = skb_put(chunk->skb, padlen);
1140 target = skb_put(chunk->skb, len);
1141
1142 memset(padding, 0, padlen);
1143 memcpy(target, data, len);
1144
1145 /* Adjust the chunk length field. */
1146 chunk->chunk_hdr->length = htons(chunklen + padlen + len);
1147 chunk->chunk_end = chunk->skb->tail;
1148
1149 return target;
1150}
1151
1152/* Append bytes from user space to the end of a chunk. Will panic if
1153 * chunk is not big enough.
1154 * Returns a kernel err value.
1155 */
1156int sctp_user_addto_chunk(struct sctp_chunk *chunk, int off, int len,
1157 struct iovec *data)
1158{
1159 __u8 *target;
1160 int err = 0;
1161
1162 /* Make room in chunk for data. */
1163 target = skb_put(chunk->skb, len);
1164
1165 /* Copy data (whole iovec) into chunk */
1166 if ((err = memcpy_fromiovecend(target, data, off, len)))
1167 goto out;
1168
1169 /* Adjust the chunk length field. */
1170 chunk->chunk_hdr->length =
1171 htons(ntohs(chunk->chunk_hdr->length) + len);
1172 chunk->chunk_end = chunk->skb->tail;
1173
1174out:
1175 return err;
1176}
1177
1178/* Helper function to assign a TSN if needed. This assumes that both
1179 * the data_hdr and association have already been assigned.
1180 */
1181void sctp_chunk_assign_ssn(struct sctp_chunk *chunk)
1182{
1183 __u16 ssn;
1184 __u16 sid;
1185
1186 if (chunk->has_ssn)
1187 return;
1188
1189 /* This is the last possible instant to assign a SSN. */
1190 if (chunk->chunk_hdr->flags & SCTP_DATA_UNORDERED) {
1191 ssn = 0;
1192 } else {
dbc16db1 1193 sid = ntohs(chunk->subh.data_hdr->stream);
1da177e4
LT		 1194 if (chunk->chunk_hdr->flags & SCTP_DATA_LAST_FRAG)
1195 ssn = sctp_ssn_next(&chunk->asoc->ssnmap->out, sid);
1196 else
1197 ssn = sctp_ssn_peek(&chunk->asoc->ssnmap->out, sid);
1da177e4
LT		 1198 }
1199
9f81bcd9 1200 chunk->subh.data_hdr->ssn = htons(ssn);
1da177e4
LT		 1201 chunk->has_ssn = 1;
1202}
1203
1204/* Helper function to assign a TSN if needed. This assumes that both
1205 * the data_hdr and association have already been assigned.
1206 */
1207void sctp_chunk_assign_tsn(struct sctp_chunk *chunk)
1208{
1209 if (!chunk->has_tsn) {
1210 /* This is the last possible instant to
1211 * assign a TSN.
1212 */
1213 chunk->subh.data_hdr->tsn =
1214 htonl(sctp_association_get_next_tsn(chunk->asoc));
1215 chunk->has_tsn = 1;
1216 }
1217}
1218
1219/* Create a CLOSED association to use with an incoming packet. */
1220struct sctp_association *sctp_make_temp_asoc(const struct sctp_endpoint *ep,
3182cd84 1221 struct sctp_chunk *chunk,
dd0fc66f 1222 gfp_t gfp)
1da177e4
LT		 1223{
1224 struct sctp_association *asoc;
1225 struct sk_buff *skb;
1226 sctp_scope_t scope;
1227 struct sctp_af *af;
1228
1229 /* Create the bare association. */
1230 scope = sctp_scope(sctp_source(chunk));
1231 asoc = sctp_association_new(ep, ep->base.sk, scope, gfp);
1232 if (!asoc)
1233 goto nodata;
1234 asoc->temp = 1;
1235 skb = chunk->skb;
1236 /* Create an entry for the source address of the packet. */
1237 af = sctp_get_af_specific(ipver2af(skb->nh.iph->version));
1238 if (unlikely(!af))
1239 goto fail;
d55c41b1 1240 af->from_skb(&asoc->c.peer_addr, skb, 1);
1da177e4
LT		 1241nodata:
1242 return asoc;
1243
1244fail:
1245 sctp_association_free(asoc);
1246 return NULL;
1247}
1248
1249/* Build a cookie representing asoc.
1250 * This INCLUDES the param header needed to put the cookie in the INIT ACK.
1251 */
1252static sctp_cookie_param_t *sctp_pack_cookie(const struct sctp_endpoint *ep,
1253 const struct sctp_association *asoc,
1254 const struct sctp_chunk *init_chunk,
1255 int *cookie_len,
1256 const __u8 *raw_addrs, int addrs_len)
1257{
1258 sctp_cookie_param_t *retval;
1259 struct sctp_signed_cookie *cookie;
1260 struct scatterlist sg;
1261 int headersize, bodysize;
1262 unsigned int keylen;
1263 char *key;
1264
9834a2bb
VY		 1265 /* Header size is static data prior to the actual cookie, including
1266 * any padding.
1267 */
1268 headersize = sizeof(sctp_paramhdr_t) +
1269 (sizeof(struct sctp_signed_cookie) -
1270 sizeof(struct sctp_cookie));
1da177e4
LT		 1271 bodysize = sizeof(struct sctp_cookie)
1272 + ntohs(init_chunk->chunk_hdr->length) + addrs_len;
1273
1274 /* Pad out the cookie to a multiple to make the signature
1275 * functions simpler to write.
1276 */
1277 if (bodysize % SCTP_COOKIE_MULTIPLE)
1278 bodysize += SCTP_COOKIE_MULTIPLE
1279 - (bodysize % SCTP_COOKIE_MULTIPLE);
1280 *cookie_len = headersize + bodysize;
1281
1da177e4
LT		 1282 /* Clear this memory since we are sending this data structure
1283 * out on the network.
1284 */
af997d8c
ACM		 1285 retval = kzalloc(*cookie_len, GFP_ATOMIC);
1286 if (!retval)
1287 goto nodata;
1288
1da177e4
LT		 1289 cookie = (struct sctp_signed_cookie *) retval->body;
1290
1291 /* Set up the parameter header. */
1292 retval->p.type = SCTP_PARAM_STATE_COOKIE;
1293 retval->p.length = htons(*cookie_len);
1294
1295 /* Copy the cookie part of the association itself. */
1296 cookie->c = asoc->c;
1297 /* Save the raw address list length in the cookie. */
1298 cookie->c.raw_addr_list_len = addrs_len;
1299
1300 /* Remember PR-SCTP capability. */
1301 cookie->c.prsctp_capable = asoc->peer.prsctp_capable;
1302
0f3fffd8
ISJ		 1303 /* Save adaptation indication in the cookie. */
1304 cookie->c.adaptation_ind = asoc->peer.adaptation_ind;
1da177e4
LT		 1305
1306 /* Set an expiration time for the cookie. */
1307 do_gettimeofday(&cookie->c.expiration);
1308 TIMEVAL_ADD(asoc->cookie_life, cookie->c.expiration);
1309
1310 /* Copy the peer's init packet. */
1311 memcpy(&cookie->c.peer_init[0], init_chunk->chunk_hdr,
1312 ntohs(init_chunk->chunk_hdr->length));
1313
1314 /* Copy the raw local address list of the association. */
1315 memcpy((__u8 *)&cookie->c.peer_init[0] +
1316 ntohs(init_chunk->chunk_hdr->length), raw_addrs, addrs_len);
1317
1318 if (sctp_sk(ep->base.sk)->hmac) {
1b489e11
HX		 1319 struct hash_desc desc;
1320
1da177e4
LT		 1321 /* Sign the message. */
1322 sg.page = virt_to_page(&cookie->c);
1323 sg.offset = (unsigned long)(&cookie->c) % PAGE_SIZE;
1324 sg.length = bodysize;
1325 keylen = SCTP_SECRET_SIZE;
1326 key = (char *)ep->secret_key[ep->current_key];
1b489e11
HX		 1327 desc.tfm = sctp_sk(ep->base.sk)->hmac;
1328 desc.flags = 0;
1da177e4 1329
1b489e11
HX		 1330 if (crypto_hash_setkey(desc.tfm, key, keylen) ||
1331 crypto_hash_digest(&desc, &sg, bodysize, cookie->signature))
1332 goto free_cookie;
1da177e4
LT		 1333 }
1334
1da177e4 1335 return retval;
1b489e11
HX		 1336
1337free_cookie:
1338 kfree(retval);
1339nodata:
1340 *cookie_len = 0;
1341 return NULL;
1da177e4
LT		 1342}
1343
1344/* Unpack the cookie from COOKIE ECHO chunk, recreating the association. */
1345struct sctp_association *sctp_unpack_cookie(
1346 const struct sctp_endpoint *ep,
1347 const struct sctp_association *asoc,
dd0fc66f 1348 struct sctp_chunk *chunk, gfp_t gfp,
1da177e4
LT		 1349 int *error, struct sctp_chunk **errp)
1350{
1351 struct sctp_association *retval = NULL;
1352 struct sctp_signed_cookie *cookie;
1353 struct sctp_cookie *bear_cookie;
1354 int headersize, bodysize, fixed_size;
313e7b4d 1355 __u8 *digest = ep->digest;
1da177e4
LT		 1356 struct scatterlist sg;
1357 unsigned int keylen, len;
1358 char *key;
1359 sctp_scope_t scope;
1360 struct sk_buff *skb = chunk->skb;
a61bbcf2 1361 struct timeval tv;
1b489e11 1362 struct hash_desc desc;
1da177e4 1363
9834a2bb
VY		 1364 /* Header size is static data prior to the actual cookie, including
1365 * any padding.
1366 */
1367 headersize = sizeof(sctp_chunkhdr_t) +
1368 (sizeof(struct sctp_signed_cookie) -
1369 sizeof(struct sctp_cookie));
1da177e4
LT		 1370 bodysize = ntohs(chunk->chunk_hdr->length) - headersize;
1371 fixed_size = headersize + sizeof(struct sctp_cookie);
1372
1373 /* Verify that the chunk looks like it even has a cookie.
1374 * There must be enough room for our cookie and our peer's
1375 * INIT chunk.
1376 */
1377 len = ntohs(chunk->chunk_hdr->length);
1378 if (len < fixed_size + sizeof(struct sctp_chunkhdr))
1379 goto malformed;
1380
1381 /* Verify that the cookie has been padded out. */
1382 if (bodysize % SCTP_COOKIE_MULTIPLE)
1383 goto malformed;
1384
1385 /* Process the cookie. */
1386 cookie = chunk->subh.cookie_hdr;
1387 bear_cookie = &cookie->c;
1388
1389 if (!sctp_sk(ep->base.sk)->hmac)
1390 goto no_hmac;
1391
1392 /* Check the signature. */
1393 keylen = SCTP_SECRET_SIZE;
1394 sg.page = virt_to_page(bear_cookie);
1395 sg.offset = (unsigned long)(bear_cookie) % PAGE_SIZE;
1396 sg.length = bodysize;
1397 key = (char *)ep->secret_key[ep->current_key];
1b489e11
HX		 1398 desc.tfm = sctp_sk(ep->base.sk)->hmac;
1399 desc.flags = 0;
1da177e4 1400
8ca84481 1401 memset(digest, 0x00, SCTP_SIGNATURE_SIZE);
1b489e11
HX		 1402 if (crypto_hash_setkey(desc.tfm, key, keylen) ||
1403 crypto_hash_digest(&desc, &sg, bodysize, digest)) {
1404 *error = -SCTP_IERROR_NOMEM;
1405 goto fail;
1406 }
1da177e4
LT		 1407
1408 if (memcmp(digest, cookie->signature, SCTP_SIGNATURE_SIZE)) {
1409 /* Try the previous key. */
1410 key = (char *)ep->secret_key[ep->last_key];
8ca84481 1411 memset(digest, 0x00, SCTP_SIGNATURE_SIZE);
1b489e11
HX		 1412 if (crypto_hash_setkey(desc.tfm, key, keylen) ||
1413 crypto_hash_digest(&desc, &sg, bodysize, digest)) {
1414 *error = -SCTP_IERROR_NOMEM;
1415 goto fail;
1416 }
1da177e4
LT		 1417
1418 if (memcmp(digest, cookie->signature, SCTP_SIGNATURE_SIZE)) {
1419 /* Yikes! Still bad signature! */
1420 *error = -SCTP_IERROR_BAD_SIG;
1421 goto fail;
1422 }
1423 }
1424
1425no_hmac:
1426 /* IG Section 2.35.2:
1427 * 3) Compare the port numbers and the verification tag contained
1428 * within the COOKIE ECHO chunk to the actual port numbers and the
1429 * verification tag within the SCTP common header of the received
1430 * packet. If these values do not match the packet MUST be silently
1431 * discarded,
1432 */
1433 if (ntohl(chunk->sctp_hdr->vtag) != bear_cookie->my_vtag) {
1434 *error = -SCTP_IERROR_BAD_TAG;
1435 goto fail;
1436 }
1437
9b1dfad0 1438 if (chunk->sctp_hdr->source != bear_cookie->peer_addr.v4.sin_port ||
1da177e4
LT		 1439 ntohs(chunk->sctp_hdr->dest) != bear_cookie->my_port) {
1440 *error = -SCTP_IERROR_BAD_PORTS;
1441 goto fail;
1442 }
1443
1444 /* Check to see if the cookie is stale. If there is already
1445 * an association, there is no need to check cookie's expiration
1446 * for init collision case of lost COOKIE ACK.
f236218b
VY		 1447 * If skb has been timestamped, then use the stamp, otherwise
1448 * use current time. This introduces a small possibility that
1449 * that a cookie may be considered expired, but his would only slow
1450 * down the new association establishment instead of every packet.
1da177e4 1451 */
f236218b
VY		 1452 if (sock_flag(ep->base.sk, SOCK_TIMESTAMP))
1453 skb_get_timestamp(skb, &tv);
1454 else
1455 do_gettimeofday(&tv);
1456
a61bbcf2 1457 if (!asoc && tv_lt(bear_cookie->expiration, tv)) {
1da177e4
LT		 1458 __u16 len;
1459 /*
1460 * Section 3.3.10.3 Stale Cookie Error (3)
1461 *
1462 * Cause of error
1463 * ---------------
1464 * Stale Cookie Error: Indicates the receipt of a valid State
1465 * Cookie that has expired.
1466 */
1467 len = ntohs(chunk->chunk_hdr->length);
1468 *errp = sctp_make_op_error_space(asoc, chunk, len);
1469 if (*errp) {
a61bbcf2 1470 suseconds_t usecs = (tv.tv_sec -
1da177e4 1471 bear_cookie->expiration.tv_sec) * 1000000L +
a61bbcf2 1472 tv.tv_usec - bear_cookie->expiration.tv_usec;
34bcca28 1473 __be32 n = htonl(usecs);
1da177e4 1474
1da177e4 1475 sctp_init_cause(*errp, SCTP_ERROR_STALE_COOKIE,
34bcca28 1476 &n, sizeof(n));
1da177e4
LT		 1477 *error = -SCTP_IERROR_STALE_COOKIE;
1478 } else
1479 *error = -SCTP_IERROR_NOMEM;
1480
1481 goto fail;
1482 }
1483
1484 /* Make a new base association. */
1485 scope = sctp_scope(sctp_source(chunk));
1486 retval = sctp_association_new(ep, ep->base.sk, scope, gfp);
1487 if (!retval) {
1488 *error = -SCTP_IERROR_NOMEM;
1489 goto fail;
1490 }
1491
1492 /* Set up our peer's port number. */
1493 retval->peer.port = ntohs(chunk->sctp_hdr->source);
1494
1495 /* Populate the association from the cookie. */
1496 memcpy(&retval->c, bear_cookie, sizeof(*bear_cookie));
1497
1498 if (sctp_assoc_set_bind_addr_from_cookie(retval, bear_cookie,
1499 GFP_ATOMIC) < 0) {
1500 *error = -SCTP_IERROR_NOMEM;
1501 goto fail;
1502 }
1503
1504 /* Also, add the destination address. */
1505 if (list_empty(&retval->base.bind_addr.address_list)) {
16b0a030 1506 sctp_add_bind_addr(&retval->base.bind_addr, &chunk->dest, 1,
1da177e4
LT		 1507 GFP_ATOMIC);
1508 }
1509
1510 retval->next_tsn = retval->c.initial_tsn;
1511 retval->ctsn_ack_point = retval->next_tsn - 1;
1512 retval->addip_serial = retval->c.initial_tsn;
1513 retval->adv_peer_ack_point = retval->ctsn_ack_point;
1514 retval->peer.prsctp_capable = retval->c.prsctp_capable;
0f3fffd8 1515 retval->peer.adaptation_ind = retval->c.adaptation_ind;
1da177e4
LT		 1516
1517 /* The INIT stuff will be done by the side effects. */
1518 return retval;
1519
1520fail:
1521 if (retval)
1522 sctp_association_free(retval);
1523
1524 return NULL;
1525
1526malformed:
1527 /* Yikes! The packet is either corrupt or deliberately
1528 * malformed.
1529 */
1530 *error = -SCTP_IERROR_MALFORMED;
1531 goto fail;
1532}
1533
1534/********************************************************************
1535 * 3rd Level Abstractions
1536 ********************************************************************/
1537
1538struct __sctp_missing {
9f81bcd9
AV		 1539 __be32 num_missing;
1540 __be16 type;
1da177e4
LT		 1541} __attribute__((packed));
1542
1543/*
1544 * Report a missing mandatory parameter.
1545 */
1546static int sctp_process_missing_param(const struct sctp_association *asoc,
1547 sctp_param_t paramtype,
1548 struct sctp_chunk *chunk,
1549 struct sctp_chunk **errp)
1550{
1551 struct __sctp_missing report;
1552 __u16 len;
1553
1554 len = WORD_ROUND(sizeof(report));
1555
1556 /* Make an ERROR chunk, preparing enough room for
1557 * returning multiple unknown parameters.
1558 */
1559 if (!*errp)
1560 *errp = sctp_make_op_error_space(asoc, chunk, len);
1561
1562 if (*errp) {
1563 report.num_missing = htonl(1);
1564 report.type = paramtype;
ebdfcad4 1565 sctp_init_cause(*errp, SCTP_ERROR_MISS_PARAM,
1da177e4
LT		 1566 &report, sizeof(report));
1567 }
1568
1569 /* Stop processing this chunk. */
1570 return 0;
1571}
1572
1573/* Report an Invalid Mandatory Parameter. */
1574static int sctp_process_inv_mandatory(const struct sctp_association *asoc,
1575 struct sctp_chunk *chunk,
1576 struct sctp_chunk **errp)
1577{
1578 /* Invalid Mandatory Parameter Error has no payload. */
1579
1580 if (!*errp)
1581 *errp = sctp_make_op_error_space(asoc, chunk, 0);
1582
1583 if (*errp)
1584 sctp_init_cause(*errp, SCTP_ERROR_INV_PARAM, NULL, 0);
1585
1586 /* Stop processing this chunk. */
1587 return 0;
1588}
1589
1590static int sctp_process_inv_paramlength(const struct sctp_association *asoc,
1591 struct sctp_paramhdr *param,
1592 const struct sctp_chunk *chunk,
1593 struct sctp_chunk **errp)
1594{
1595 char error[] = "The following parameter had invalid length:";
1596 size_t payload_len = WORD_ROUND(sizeof(error)) +
1597 sizeof(sctp_paramhdr_t);
1598
1599
1600 /* Create an error chunk and fill it in with our payload. */
1601 if (!*errp)
1602 *errp = sctp_make_op_error_space(asoc, chunk, payload_len);
1603
1604 if (*errp) {
1605 sctp_init_cause(*errp, SCTP_ERROR_PROTO_VIOLATION, error,
1606 sizeof(error));
1607 sctp_addto_chunk(*errp, sizeof(sctp_paramhdr_t), param);
1608 }
1609
1610 return 0;
1611}
1612
1613
1614/* Do not attempt to handle the HOST_NAME parm. However, do
1615 * send back an indicator to the peer.
1616 */
1617static int sctp_process_hn_param(const struct sctp_association *asoc,
1618 union sctp_params param,
1619 struct sctp_chunk *chunk,
1620 struct sctp_chunk **errp)
1621{
1622 __u16 len = ntohs(param.p->length);
1623
1624 /* Make an ERROR chunk. */
1625 if (!*errp)
1626 *errp = sctp_make_op_error_space(asoc, chunk, len);
1627
1628 if (*errp)
1629 sctp_init_cause(*errp, SCTP_ERROR_DNS_FAILED,
1630 param.v, len);
1631
1632 /* Stop processing this chunk. */
1633 return 0;
1634}
1635
1636/* RFC 3.2.1 & the Implementers Guide 2.2.
1637 *
1638 * The Parameter Types are encoded such that the
1639 * highest-order two bits specify the action that must be
1640 * taken if the processing endpoint does not recognize the
1641 * Parameter Type.
1642 *
1643 * 00 - Stop processing this SCTP chunk and discard it,
1644 * do not process any further chunks within it.
1645 *
1646 * 01 - Stop processing this SCTP chunk and discard it,
1647 * do not process any further chunks within it, and report
1648 * the unrecognized parameter in an 'Unrecognized
1649 * Parameter Type' (in either an ERROR or in the INIT ACK).
1650 *
1651 * 10 - Skip this parameter and continue processing.
1652 *
1653 * 11 - Skip this parameter and continue processing but
1654 * report the unrecognized parameter in an
1655 * 'Unrecognized Parameter Type' (in either an ERROR or in
1656 * the INIT ACK).
1657 *
1658 * Return value:
1659 * 0 - discard the chunk
1660 * 1 - continue with the chunk
1661 */
1662static int sctp_process_unk_param(const struct sctp_association *asoc,
1663 union sctp_params param,
1664 struct sctp_chunk *chunk,
1665 struct sctp_chunk **errp)
1666{
1667 int retval = 1;
1668
1669 switch (param.p->type & SCTP_PARAM_ACTION_MASK) {
1670 case SCTP_PARAM_ACTION_DISCARD:
1671 retval = 0;
1672 break;
1673 case SCTP_PARAM_ACTION_DISCARD_ERR:
1674 retval = 0;
1675 /* Make an ERROR chunk, preparing enough room for
1676 * returning multiple unknown parameters.
1677 */
1678 if (NULL == *errp)
1679 *errp = sctp_make_op_error_space(asoc, chunk,
1680 ntohs(chunk->chunk_hdr->length));
1681
1682 if (*errp)
1683 sctp_init_cause(*errp, SCTP_ERROR_UNKNOWN_PARAM,
1684 param.v,
1685 WORD_ROUND(ntohs(param.p->length)));
1686
1687 break;
1688 case SCTP_PARAM_ACTION_SKIP:
1689 break;
1690 case SCTP_PARAM_ACTION_SKIP_ERR:
1691 /* Make an ERROR chunk, preparing enough room for
1692 * returning multiple unknown parameters.
1693 */
1694 if (NULL == *errp)
1695 *errp = sctp_make_op_error_space(asoc, chunk,
1696 ntohs(chunk->chunk_hdr->length));
1697
1698 if (*errp) {
1699 sctp_init_cause(*errp, SCTP_ERROR_UNKNOWN_PARAM,
1700 param.v,
1701 WORD_ROUND(ntohs(param.p->length)));
1702 } else {
1703 /* If there is no memory for generating the ERROR
1704 * report as specified, an ABORT will be triggered
1705 * to the peer and the association won't be
1706 * established.
1707 */
1708 retval = 0;
1709 }
1710
1711 break;
1712 default:
1713 break;
1714 }
1715
1716 return retval;
1717}
1718
1719/* Find unrecognized parameters in the chunk.
1720 * Return values:
1721 * 0 - discard the chunk
1722 * 1 - continue with the chunk
1723 */
1724static int sctp_verify_param(const struct sctp_association *asoc,
1725 union sctp_params param,
1726 sctp_cid_t cid,
1727 struct sctp_chunk *chunk,
1728 struct sctp_chunk **err_chunk)
1729{
1730 int retval = 1;
1731
1732 /* FIXME - This routine is not looking at each parameter per the
1733 * chunk type, i.e., unrecognized parameters should be further
1734 * identified based on the chunk id.
1735 */
1736
1737 switch (param.p->type) {
1738 case SCTP_PARAM_IPV4_ADDRESS:
1739 case SCTP_PARAM_IPV6_ADDRESS:
1740 case SCTP_PARAM_COOKIE_PRESERVATIVE:
1741 case SCTP_PARAM_SUPPORTED_ADDRESS_TYPES:
1742 case SCTP_PARAM_STATE_COOKIE:
1743 case SCTP_PARAM_HEARTBEAT_INFO:
1744 case SCTP_PARAM_UNRECOGNIZED_PARAMETERS:
1745 case SCTP_PARAM_ECN_CAPABLE:
0f3fffd8 1746 case SCTP_PARAM_ADAPTATION_LAYER_IND:
1da177e4
LT		 1747 break;
1748
1749 case SCTP_PARAM_HOST_NAME_ADDRESS:
1750 /* Tell the peer, we won't support this param. */
1751 return sctp_process_hn_param(asoc, param, chunk, err_chunk);
1752 case SCTP_PARAM_FWD_TSN_SUPPORT:
1753 if (sctp_prsctp_enable)
1754 break;
1755 /* Fall Through */
1756 default:
1757 SCTP_DEBUG_PRINTK("Unrecognized param: %d for chunk %d.\n",
1758 ntohs(param.p->type), cid);
1759 return sctp_process_unk_param(asoc, param, chunk, err_chunk);
1760
1761 break;
1762 }
1763 return retval;
1764}
1765
1766/* Verify the INIT packet before we process it. */
1767int sctp_verify_init(const struct sctp_association *asoc,
1768 sctp_cid_t cid,
1769 sctp_init_chunk_t *peer_init,
1770 struct sctp_chunk *chunk,
1771 struct sctp_chunk **errp)
1772{
1773 union sctp_params param;
1774 int has_cookie = 0;
1775
1776 /* Verify stream values are non-zero. */
1777 if ((0 == peer_init->init_hdr.num_outbound_streams) ||
d023f629
VY		 1778 (0 == peer_init->init_hdr.num_inbound_streams) ||
1779 (0 == peer_init->init_hdr.init_tag) ||
1780 (SCTP_DEFAULT_MINWINDOW > ntohl(peer_init->init_hdr.a_rwnd))) {
1da177e4
LT		 1781
1782 sctp_process_inv_mandatory(asoc, chunk, errp);
1783 return 0;
1784 }
1785
1786 /* Check for missing mandatory parameters. */
1787 sctp_walk_params(param, peer_init, init_hdr.params) {
1788
1789 if (SCTP_PARAM_STATE_COOKIE == param.p->type)
1790 has_cookie = 1;
1791
1792 } /* for (loop through all parameters) */
1793
1794 /* There is a possibility that a parameter length was bad and
1795 * in that case we would have stoped walking the parameters.
1796 * The current param.p would point at the bad one.
1797 * Current consensus on the mailing list is to generate a PROTOCOL
1798 * VIOLATION error. We build the ERROR chunk here and let the normal
1799 * error handling code build and send the packet.
1800 */
1801 if (param.v < (void*)chunk->chunk_end - sizeof(sctp_paramhdr_t)) {
1802 sctp_process_inv_paramlength(asoc, param.p, chunk, errp);
1803 return 0;
1804 }
1805
1806 /* The only missing mandatory param possible today is
1807 * the state cookie for an INIT-ACK chunk.
1808 */
1809 if ((SCTP_CID_INIT_ACK == cid) && !has_cookie) {
1810 sctp_process_missing_param(asoc, SCTP_PARAM_STATE_COOKIE,
1811 chunk, errp);
1812 return 0;
1813 }
1814
1815 /* Find unrecognized parameters. */
1816
1817 sctp_walk_params(param, peer_init, init_hdr.params) {
1818
1819 if (!sctp_verify_param(asoc, param, cid, chunk, errp)) {
1820 if (SCTP_PARAM_HOST_NAME_ADDRESS == param.p->type)
1821 return 0;
1822 else
1823 return 1;
1824 }
1825
1826 } /* for (loop through all parameters) */
1827
1828 return 1;
1829}
1830
1831/* Unpack the parameters in an INIT packet into an association.
1832 * Returns 0 on failure, else success.
1833 * FIXME: This is an association method.
1834 */
1835int sctp_process_init(struct sctp_association *asoc, sctp_cid_t cid,
1836 const union sctp_addr *peer_addr,
dd0fc66f 1837 sctp_init_chunk_t *peer_init, gfp_t gfp)
1da177e4
LT		 1838{
1839 union sctp_params param;
1840 struct sctp_transport *transport;
1841 struct list_head *pos, *temp;
1842 char *cookie;
1843
1844 /* We must include the address that the INIT packet came from.
1845 * This is the only address that matters for an INIT packet.
1846 * When processing a COOKIE ECHO, we retrieve the from address
1847 * of the INIT from the cookie.
1848 */
1849
1850 /* This implementation defaults to making the first transport
1851 * added as the primary transport. The source address seems to
1852 * be a a better choice than any of the embedded addresses.
1853 */
4bdf4b5f 1854 if (peer_addr) {
6a1e5f33 1855 if(!sctp_assoc_add_peer(asoc, peer_addr, gfp, SCTP_ACTIVE))
1da177e4 1856 goto nomem;
4bdf4b5f 1857 }
1da177e4
LT		 1858
1859 /* Process the initialization parameters. */
1860
1861 sctp_walk_params(param, peer_init, init_hdr.params) {
1862
1863 if (!sctp_process_param(asoc, param, peer_addr, gfp))
1864 goto clean_up;
1865 }
1866
3f7a87d2
FF		 1867 /* Walk list of transports, removing transports in the UNKNOWN state. */
1868 list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
1869 transport = list_entry(pos, struct sctp_transport, transports);
1870 if (transport->state == SCTP_UNKNOWN) {
1871 sctp_assoc_rm_peer(asoc, transport);
1872 }
1873 }
1874
1da177e4
LT		 1875 /* The fixed INIT headers are always in network byte
1876 * order.
1877 */
1878 asoc->peer.i.init_tag =
1879 ntohl(peer_init->init_hdr.init_tag);
1880 asoc->peer.i.a_rwnd =
1881 ntohl(peer_init->init_hdr.a_rwnd);
1882 asoc->peer.i.num_outbound_streams =
1883 ntohs(peer_init->init_hdr.num_outbound_streams);
1884 asoc->peer.i.num_inbound_streams =
1885 ntohs(peer_init->init_hdr.num_inbound_streams);
1886 asoc->peer.i.initial_tsn =
1887 ntohl(peer_init->init_hdr.initial_tsn);
1888
1889 /* Apply the upper bounds for output streams based on peer's
1890 * number of inbound streams.
1891 */
1892 if (asoc->c.sinit_num_ostreams >
1893 ntohs(peer_init->init_hdr.num_inbound_streams)) {
1894 asoc->c.sinit_num_ostreams =
1895 ntohs(peer_init->init_hdr.num_inbound_streams);
1896 }
1897
1898 if (asoc->c.sinit_max_instreams >
1899 ntohs(peer_init->init_hdr.num_outbound_streams)) {
1900 asoc->c.sinit_max_instreams =
1901 ntohs(peer_init->init_hdr.num_outbound_streams);
1902 }
1903
1904 /* Copy Initiation tag from INIT to VT_peer in cookie. */
1905 asoc->c.peer_vtag = asoc->peer.i.init_tag;
1906
1907 /* Peer Rwnd : Current calculated value of the peer's rwnd. */
1908 asoc->peer.rwnd = asoc->peer.i.a_rwnd;
1909
1910 /* Copy cookie in case we need to resend COOKIE-ECHO. */
1911 cookie = asoc->peer.cookie;
1912 if (cookie) {
af997d8c 1913 asoc->peer.cookie = kmemdup(cookie, asoc->peer.cookie_len, gfp);
1da177e4
LT		 1914 if (!asoc->peer.cookie)
1915 goto clean_up;
1da177e4
LT		 1916 }
1917
1918 /* RFC 2960 7.2.1 The initial value of ssthresh MAY be arbitrarily
1919 * high (for example, implementations MAY use the size of the receiver
1920 * advertised window).
1921 */
1922 list_for_each(pos, &asoc->peer.transport_addr_list) {
1923 transport = list_entry(pos, struct sctp_transport, transports);
1924 transport->ssthresh = asoc->peer.i.a_rwnd;
1925 }
1926
1927 /* Set up the TSN tracking pieces. */
1928 sctp_tsnmap_init(&asoc->peer.tsn_map, SCTP_TSN_MAP_SIZE,
1929 asoc->peer.i.initial_tsn);
1930
1931 /* RFC 2960 6.5 Stream Identifier and Stream Sequence Number
1932 *
1933 * The stream sequence number in all the streams shall start
1934 * from 0 when the association is established. Also, when the
1935 * stream sequence number reaches the value 65535 the next
1936 * stream sequence number shall be set to 0.
1937 */
1938
3f7a87d2
FF		 1939 /* Allocate storage for the negotiated streams if it is not a temporary
1940 * association.
1da177e4
LT		 1941 */
1942 if (!asoc->temp) {
1943 int assoc_id;
1944 int error;
1945
1946 asoc->ssnmap = sctp_ssnmap_new(asoc->c.sinit_max_instreams,
1947 asoc->c.sinit_num_ostreams, gfp);
1948 if (!asoc->ssnmap)
1949 goto clean_up;
1950
1951 retry:
1952 if (unlikely(!idr_pre_get(&sctp_assocs_id, gfp)))
1953 goto clean_up;
1954 spin_lock_bh(&sctp_assocs_id_lock);
1955 error = idr_get_new_above(&sctp_assocs_id, (void *)asoc, 1,
1956 &assoc_id);
1957 spin_unlock_bh(&sctp_assocs_id_lock);
1958 if (error == -EAGAIN)
1959 goto retry;
1960 else if (error)
1961 goto clean_up;
1962
1963 asoc->assoc_id = (sctp_assoc_t) assoc_id;
1964 }
1965
1966 /* ADDIP Section 4.1 ASCONF Chunk Procedures
1967 *
1968 * When an endpoint has an ASCONF signaled change to be sent to the
1969 * remote endpoint it should do the following:
1970 * ...
1971 * A2) A serial number should be assigned to the Chunk. The serial
1972 * number should be a monotonically increasing number. All serial
1973 * numbers are defined to be initialized at the start of the
1974 * association to the same value as the Initial TSN.
1975 */
1976 asoc->peer.addip_serial = asoc->peer.i.initial_tsn - 1;
1977 return 1;
1978
1979clean_up:
1980 /* Release the transport structures. */
1981 list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
1982 transport = list_entry(pos, struct sctp_transport, transports);
1983 list_del_init(pos);
1984 sctp_transport_free(transport);
1985 }
3f7a87d2
FF		 1986
1987 asoc->peer.transport_count = 0;
1988
1da177e4
LT		 1989nomem:
1990 return 0;
1991}
1992
1993
1994/* Update asoc with the option described in param.
1995 *
1996 * RFC2960 3.3.2.1 Optional/Variable Length Parameters in INIT
1997 *
1998 * asoc is the association to update.
1999 * param is the variable length parameter to use for update.
2000 * cid tells us if this is an INIT, INIT ACK or COOKIE ECHO.
2001 * If the current packet is an INIT we want to minimize the amount of
2002 * work we do. In particular, we should not build transport
2003 * structures for the addresses.
2004 */
2005static int sctp_process_param(struct sctp_association *asoc,
2006 union sctp_params param,
2007 const union sctp_addr *peer_addr,
dd0fc66f 2008 gfp_t gfp)
1da177e4
LT		 2009{
2010 union sctp_addr addr;
2011 int i;
2012 __u16 sat;
2013 int retval = 1;
2014 sctp_scope_t scope;
2015 time_t stale;
2016 struct sctp_af *af;
2017
2018 /* We maintain all INIT parameters in network byte order all the
2019 * time. This allows us to not worry about whether the parameters
2020 * came from a fresh INIT, and INIT ACK, or were stored in a cookie.
2021 */
2022 switch (param.p->type) {
2023 case SCTP_PARAM_IPV6_ADDRESS:
2024 if (PF_INET6 != asoc->base.sk->sk_family)
2025 break;
2026 /* Fall through. */
2027 case SCTP_PARAM_IPV4_ADDRESS:
2028 af = sctp_get_af_specific(param_type2af(param.p->type));
dd86d136 2029 af->from_addr_param(&addr, param.addr, htons(asoc->peer.port), 0);
1da177e4 2030 scope = sctp_scope(peer_addr);
dd86d136
AV		 2031 if (sctp_in_scope(&addr, scope))
2032 if (!sctp_assoc_add_peer(asoc, &addr, gfp, SCTP_UNCONFIRMED))
1da177e4
LT		 2033 return 0;
2034 break;
2035
2036 case SCTP_PARAM_COOKIE_PRESERVATIVE:
2037 if (!sctp_cookie_preserve_enable)
2038 break;
2039
2040 stale = ntohl(param.life->lifespan_increment);
2041
2042 /* Suggested Cookie Life span increment's unit is msec,
2043 * (1/1000sec).
2044 */
2045 asoc->cookie_life.tv_sec += stale / 1000;
2046 asoc->cookie_life.tv_usec += (stale % 1000) * 1000;
2047 break;
2048
2049 case SCTP_PARAM_HOST_NAME_ADDRESS:
2050 SCTP_DEBUG_PRINTK("unimplemented SCTP_HOST_NAME_ADDRESS\n");
2051 break;
2052
2053 case SCTP_PARAM_SUPPORTED_ADDRESS_TYPES:
2054 /* Turn off the default values first so we'll know which
2055 * ones are really set by the peer.
2056 */
2057 asoc->peer.ipv4_address = 0;
2058 asoc->peer.ipv6_address = 0;
2059
2060 /* Cycle through address types; avoid divide by 0. */
2061 sat = ntohs(param.p->length) - sizeof(sctp_paramhdr_t);
2062 if (sat)
2063 sat /= sizeof(__u16);
2064
2065 for (i = 0; i < sat; ++i) {
2066 switch (param.sat->types[i]) {
2067 case SCTP_PARAM_IPV4_ADDRESS:
2068 asoc->peer.ipv4_address = 1;
2069 break;
2070
2071 case SCTP_PARAM_IPV6_ADDRESS:
2072 asoc->peer.ipv6_address = 1;
2073 break;
2074
2075 case SCTP_PARAM_HOST_NAME_ADDRESS:
2076 asoc->peer.hostname_address = 1;
2077 break;
2078
2079 default: /* Just ignore anything else. */
2080 break;
2081 };
2082 }
2083 break;
2084
2085 case SCTP_PARAM_STATE_COOKIE:
2086 asoc->peer.cookie_len =
2087 ntohs(param.p->length) - sizeof(sctp_paramhdr_t);
2088 asoc->peer.cookie = param.cookie->body;
2089 break;
2090
2091 case SCTP_PARAM_HEARTBEAT_INFO:
2092 /* Would be odd to receive, but it causes no problems. */
2093 break;
2094
2095 case SCTP_PARAM_UNRECOGNIZED_PARAMETERS:
2096 /* Rejected during verify stage. */
2097 break;
2098
2099 case SCTP_PARAM_ECN_CAPABLE:
2100 asoc->peer.ecn_capable = 1;
2101 break;
2102
0f3fffd8
ISJ		 2103 case SCTP_PARAM_ADAPTATION_LAYER_IND:
2104 asoc->peer.adaptation_ind = param.aind->adaptation_ind;
1da177e4
LT		 2105 break;
2106
2107 case SCTP_PARAM_FWD_TSN_SUPPORT:
2108 if (sctp_prsctp_enable) {
2109 asoc->peer.prsctp_capable = 1;
2110 break;
2111 }
2112 /* Fall Through */
2113 default:
2114 /* Any unrecognized parameters should have been caught
2115 * and handled by sctp_verify_param() which should be
2116 * called prior to this routine. Simply log the error
2117 * here.
2118 */
2119 SCTP_DEBUG_PRINTK("Ignoring param: %d for association %p.\n",
2120 ntohs(param.p->type), asoc);
2121 break;
2122 };
2123
2124 return retval;
2125}
2126
2127/* Select a new verification tag. */
2128__u32 sctp_generate_tag(const struct sctp_endpoint *ep)
2129{
2130 /* I believe that this random number generator complies with RFC1750.
2131 * A tag of 0 is reserved for special cases (e.g. INIT).
2132 */
2133 __u32 x;
2134
2135 do {
2136 get_random_bytes(&x, sizeof(__u32));
2137 } while (x == 0);
2138
2139 return x;
2140}
2141
2142/* Select an initial TSN to send during startup. */
2143__u32 sctp_generate_tsn(const struct sctp_endpoint *ep)
2144{
2145 __u32 retval;
2146
2147 get_random_bytes(&retval, sizeof(__u32));
2148 return retval;
2149}
2150
2151/*
2152 * ADDIP 3.1.1 Address Configuration Change Chunk (ASCONF)
2153 * 0 1 2 3
2154 * 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
2155 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2156 * | Type = 0xC1 | Chunk Flags | Chunk Length |
2157 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2158 * | Serial Number |
2159 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2160 * | Address Parameter |
2161 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2162 * | ASCONF Parameter #1 |
2163 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2164 * \ \
2165 * / .... /
2166 * \ \
2167 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2168 * | ASCONF Parameter #N |
2169 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2170 *
2171 * Address Parameter and other parameter will not be wrapped in this function
2172 */
2173static struct sctp_chunk *sctp_make_asconf(struct sctp_association *asoc,
2174 union sctp_addr *addr,
2175 int vparam_len)
2176{
2177 sctp_addiphdr_t asconf;
2178 struct sctp_chunk *retval;
2179 int length = sizeof(asconf) + vparam_len;
2180 union sctp_addr_param addrparam;
2181 int addrlen;
2182 struct sctp_af *af = sctp_get_af_specific(addr->v4.sin_family);
2183
2184 addrlen = af->to_addr_param(addr, &addrparam);
2185 if (!addrlen)
2186 return NULL;
2187 length += addrlen;
2188
2189 /* Create the chunk. */
2190 retval = sctp_make_chunk(asoc, SCTP_CID_ASCONF, 0, length);
2191 if (!retval)
2192 return NULL;
2193
2194 asconf.serial = htonl(asoc->addip_serial++);
2195
2196 retval->subh.addip_hdr =
2197 sctp_addto_chunk(retval, sizeof(asconf), &asconf);
2198 retval->param_hdr.v =
2199 sctp_addto_chunk(retval, addrlen, &addrparam);
2200
2201 return retval;
2202}
2203
2204/* ADDIP
2205 * 3.2.1 Add IP Address
2206 * 0 1 2 3
2207 * 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
2208 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2209 * | Type = 0xC001 | Length = Variable |
2210 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2211 * | ASCONF-Request Correlation ID |
2212 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2213 * | Address Parameter |
2214 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2215 *
2216 * 3.2.2 Delete IP Address
2217 * 0 1 2 3
2218 * 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
2219 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2220 * | Type = 0xC002 | Length = Variable |
2221 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2222 * | ASCONF-Request Correlation ID |
2223 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2224 * | Address Parameter |
2225 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2226 *
2227 */
2228struct sctp_chunk *sctp_make_asconf_update_ip(struct sctp_association *asoc,
2229 union sctp_addr *laddr,
2230 struct sockaddr *addrs,
2231 int addrcnt,
dbc16db1 2232 __be16 flags)
1da177e4
LT		 2233{
2234 sctp_addip_param_t param;
2235 struct sctp_chunk *retval;
2236 union sctp_addr_param addr_param;
2237 union sctp_addr *addr;
2238 void *addr_buf;
2239 struct sctp_af *af;
2240 int paramlen = sizeof(param);
2241 int addr_param_len = 0;
2242 int totallen = 0;
2243 int i;
2244
2245 /* Get total length of all the address parameters. */
2246 addr_buf = addrs;
2247 for (i = 0; i < addrcnt; i++) {
2248 addr = (union sctp_addr *)addr_buf;
2249 af = sctp_get_af_specific(addr->v4.sin_family);
2250 addr_param_len = af->to_addr_param(addr, &addr_param);
2251
2252 totallen += paramlen;
2253 totallen += addr_param_len;
2254
2255 addr_buf += af->sockaddr_len;
2256 }
2257
2258 /* Create an asconf chunk with the required length. */
2259 retval = sctp_make_asconf(asoc, laddr, totallen);
2260 if (!retval)
2261 return NULL;
2262
2263 /* Add the address parameters to the asconf chunk. */
2264 addr_buf = addrs;
2265 for (i = 0; i < addrcnt; i++) {
2266 addr = (union sctp_addr *)addr_buf;
2267 af = sctp_get_af_specific(addr->v4.sin_family);
2268 addr_param_len = af->to_addr_param(addr, &addr_param);
2269 param.param_hdr.type = flags;
2270 param.param_hdr.length = htons(paramlen + addr_param_len);
2271 param.crr_id = i;
2272
2273 sctp_addto_chunk(retval, paramlen, &param);
2274 sctp_addto_chunk(retval, addr_param_len, &addr_param);
2275
2276 addr_buf += af->sockaddr_len;
2277 }
2278 return retval;
2279}
2280
2281/* ADDIP
2282 * 3.2.4 Set Primary IP Address
2283 * 0 1 2 3
2284 * 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
2285 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2286 * | Type =0xC004 | Length = Variable |
2287 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2288 * | ASCONF-Request Correlation ID |
2289 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2290 * | Address Parameter |
2291 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2292 *
2293 * Create an ASCONF chunk with Set Primary IP address parameter.
2294 */
2295struct sctp_chunk *sctp_make_asconf_set_prim(struct sctp_association *asoc,
2296 union sctp_addr *addr)
2297{
2298 sctp_addip_param_t param;
2299 struct sctp_chunk *retval;
2300 int len = sizeof(param);
2301 union sctp_addr_param addrparam;
2302 int addrlen;
2303 struct sctp_af *af = sctp_get_af_specific(addr->v4.sin_family);
2304
2305 addrlen = af->to_addr_param(addr, &addrparam);
2306 if (!addrlen)
2307 return NULL;
2308 len += addrlen;
2309
2310 /* Create the chunk and make asconf header. */
2311 retval = sctp_make_asconf(asoc, addr, len);
2312 if (!retval)
2313 return NULL;
2314
2315 param.param_hdr.type = SCTP_PARAM_SET_PRIMARY;
2316 param.param_hdr.length = htons(len);
2317 param.crr_id = 0;
2318
2319 sctp_addto_chunk(retval, sizeof(param), &param);
2320 sctp_addto_chunk(retval, addrlen, &addrparam);
2321
2322 return retval;
2323}
2324
2325/* ADDIP 3.1.2 Address Configuration Acknowledgement Chunk (ASCONF-ACK)
2326 * 0 1 2 3
2327 * 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
2328 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2329 * | Type = 0x80 | Chunk Flags | Chunk Length |
2330 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2331 * | Serial Number |
2332 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2333 * | ASCONF Parameter Response#1 |
2334 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2335 * \ \
2336 * / .... /
2337 * \ \
2338 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2339 * | ASCONF Parameter Response#N |
2340 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2341 *
2342 * Create an ASCONF_ACK chunk with enough space for the parameter responses.
2343 */
2344static struct sctp_chunk *sctp_make_asconf_ack(const struct sctp_association *asoc,
2345 __u32 serial, int vparam_len)
2346{
2347 sctp_addiphdr_t asconf;
2348 struct sctp_chunk *retval;
2349 int length = sizeof(asconf) + vparam_len;
2350
2351 /* Create the chunk. */
2352 retval = sctp_make_chunk(asoc, SCTP_CID_ASCONF_ACK, 0, length);
2353 if (!retval)
2354 return NULL;
2355
2356 asconf.serial = htonl(serial);
2357
2358 retval->subh.addip_hdr =
2359 sctp_addto_chunk(retval, sizeof(asconf), &asconf);
2360
2361 return retval;
2362}
2363
2364/* Add response parameters to an ASCONF_ACK chunk. */
9f81bcd9 2365static void sctp_add_asconf_response(struct sctp_chunk *chunk, __be32 crr_id,
dbc16db1 2366 __be16 err_code, sctp_addip_param_t *asconf_param)
1da177e4
LT		 2367{
2368 sctp_addip_param_t ack_param;
2369 sctp_errhdr_t err_param;
2370 int asconf_param_len = 0;
2371 int err_param_len = 0;
dbc16db1 2372 __be16 response_type;
1da177e4
LT		 2373
2374 if (SCTP_ERROR_NO_ERROR == err_code) {
2375 response_type = SCTP_PARAM_SUCCESS_REPORT;
2376 } else {
2377 response_type = SCTP_PARAM_ERR_CAUSE;
2378 err_param_len = sizeof(err_param);
2379 if (asconf_param)
2380 asconf_param_len =
2381 ntohs(asconf_param->param_hdr.length);
2382 }
2383
2384 /* Add Success Indication or Error Cause Indication parameter. */
2385 ack_param.param_hdr.type = response_type;
2386 ack_param.param_hdr.length = htons(sizeof(ack_param) +
2387 err_param_len +
2388 asconf_param_len);
2389 ack_param.crr_id = crr_id;
2390 sctp_addto_chunk(chunk, sizeof(ack_param), &ack_param);
2391
2392 if (SCTP_ERROR_NO_ERROR == err_code)
2393 return;
2394
2395 /* Add Error Cause parameter. */
2396 err_param.cause = err_code;
2397 err_param.length = htons(err_param_len + asconf_param_len);
2398 sctp_addto_chunk(chunk, err_param_len, &err_param);
2399
2400 /* Add the failed TLV copied from ASCONF chunk. */
2401 if (asconf_param)
2402 sctp_addto_chunk(chunk, asconf_param_len, asconf_param);
2403}
2404
2405/* Process a asconf parameter. */
dbc16db1 2406static __be16 sctp_process_asconf_param(struct sctp_association *asoc,
1da177e4
LT		 2407 struct sctp_chunk *asconf,
2408 sctp_addip_param_t *asconf_param)
2409{
2410 struct sctp_transport *peer;
2411 struct sctp_af *af;
2412 union sctp_addr addr;
2413 struct list_head *pos;
2414 union sctp_addr_param *addr_param;
5f242a13 2415
1da177e4
LT		 2416 addr_param = (union sctp_addr_param *)
2417 ((void *)asconf_param + sizeof(sctp_addip_param_t));
2418
2419 af = sctp_get_af_specific(param_type2af(addr_param->v4.param_hdr.type));
2420 if (unlikely(!af))
2421 return SCTP_ERROR_INV_PARAM;
2422
dd86d136 2423 af->from_addr_param(&addr, addr_param, htons(asoc->peer.port), 0);
1da177e4
LT		 2424 switch (asconf_param->param_hdr.type) {
2425 case SCTP_PARAM_ADD_IP:
2426 /* ADDIP 4.3 D9) If an endpoint receives an ADD IP address
2427 * request and does not have the local resources to add this
2428 * new address to the association, it MUST return an Error
2429 * Cause TLV set to the new error code 'Operation Refused
2430 * Due to Resource Shortage'.
2431 */
2432
dd86d136 2433 peer = sctp_assoc_add_peer(asoc, &addr, GFP_ATOMIC, SCTP_UNCONFIRMED);
1da177e4
LT		 2434 if (!peer)
2435 return SCTP_ERROR_RSRC_LOW;
2436
2437 /* Start the heartbeat timer. */
2438 if (!mod_timer(&peer->hb_timer, sctp_transport_timeout(peer)))
2439 sctp_transport_hold(peer);
2440 break;
2441 case SCTP_PARAM_DEL_IP:
2442 /* ADDIP 4.3 D7) If a request is received to delete the
2443 * last remaining IP address of a peer endpoint, the receiver
2444 * MUST send an Error Cause TLV with the error cause set to the
2445 * new error code 'Request to Delete Last Remaining IP Address'.
2446 */
2447 pos = asoc->peer.transport_addr_list.next;
2448 if (pos->next == &asoc->peer.transport_addr_list)
2449 return SCTP_ERROR_DEL_LAST_IP;
2450
2451 /* ADDIP 4.3 D8) If a request is received to delete an IP
2452 * address which is also the source address of the IP packet
2453 * which contained the ASCONF chunk, the receiver MUST reject
2454 * this request. To reject the request the receiver MUST send
2455 * an Error Cause TLV set to the new error code 'Request to
2456 * Delete Source IP Address'
2457 */
6a1e5f33 2458 if (sctp_cmp_addr_exact(sctp_source(asconf), &addr))
1da177e4
LT		 2459 return SCTP_ERROR_DEL_SRC_IP;
2460
dd86d136 2461 sctp_assoc_del_peer(asoc, &addr);
1da177e4
LT		 2462 break;
2463 case SCTP_PARAM_SET_PRIMARY:
dd86d136 2464 peer = sctp_assoc_lookup_paddr(asoc, &addr);
1da177e4
LT		 2465 if (!peer)
2466 return SCTP_ERROR_INV_PARAM;
2467
2468 sctp_assoc_set_primary(asoc, peer);
2469 break;
2470 default:
2471 return SCTP_ERROR_INV_PARAM;
2472 break;
2473 }
2474
2475 return SCTP_ERROR_NO_ERROR;
2476}
2477
2478/* Process an incoming ASCONF chunk with the next expected serial no. and
2479 * return an ASCONF_ACK chunk to be sent in response.
2480 */
2481struct sctp_chunk *sctp_process_asconf(struct sctp_association *asoc,
2482 struct sctp_chunk *asconf)
2483{
2484 sctp_addiphdr_t *hdr;
2485 union sctp_addr_param *addr_param;
2486 sctp_addip_param_t *asconf_param;
2487 struct sctp_chunk *asconf_ack;
2488
dbc16db1 2489 __be16 err_code;
1da177e4
LT		 2490 int length = 0;
2491 int chunk_len = asconf->skb->len;
2492 __u32 serial;
2493 int all_param_pass = 1;
2494
2495 hdr = (sctp_addiphdr_t *)asconf->skb->data;
2496 serial = ntohl(hdr->serial);
2497
2498 /* Skip the addiphdr and store a pointer to address parameter. */
2499 length = sizeof(sctp_addiphdr_t);
2500 addr_param = (union sctp_addr_param *)(asconf->skb->data + length);
2501 chunk_len -= length;
2502
2503 /* Skip the address parameter and store a pointer to the first
2504 * asconf paramter.
2505 */
2506 length = ntohs(addr_param->v4.param_hdr.length);
2507 asconf_param = (sctp_addip_param_t *)((void *)addr_param + length);
2508 chunk_len -= length;
2509
2510 /* create an ASCONF_ACK chunk.
2511 * Based on the definitions of parameters, we know that the size of
2512 * ASCONF_ACK parameters are less than or equal to the twice of ASCONF
2513 * paramters.
2514 */
2515 asconf_ack = sctp_make_asconf_ack(asoc, serial, chunk_len * 2);
2516 if (!asconf_ack)
2517 goto done;
2518
2519 /* Process the TLVs contained within the ASCONF chunk. */
2520 while (chunk_len > 0) {
2521 err_code = sctp_process_asconf_param(asoc, asconf,
2522 asconf_param);
2523 /* ADDIP 4.1 A7)
2524 * If an error response is received for a TLV parameter,
2525 * all TLVs with no response before the failed TLV are
2526 * considered successful if not reported. All TLVs after
2527 * the failed response are considered unsuccessful unless
2528 * a specific success indication is present for the parameter.
2529 */
2530 if (SCTP_ERROR_NO_ERROR != err_code)
2531 all_param_pass = 0;
2532
2533 if (!all_param_pass)
2534 sctp_add_asconf_response(asconf_ack,
2535 asconf_param->crr_id, err_code,
2536 asconf_param);
2537
2538 /* ADDIP 4.3 D11) When an endpoint receiving an ASCONF to add
2539 * an IP address sends an 'Out of Resource' in its response, it
2540 * MUST also fail any subsequent add or delete requests bundled
2541 * in the ASCONF.
2542 */
2543 if (SCTP_ERROR_RSRC_LOW == err_code)
2544 goto done;
2545
2546 /* Move to the next ASCONF param. */
2547 length = ntohs(asconf_param->param_hdr.length);
2548 asconf_param = (sctp_addip_param_t *)((void *)asconf_param +
2549 length);
2550 chunk_len -= length;
2551 }
2552
2553done:
2554 asoc->peer.addip_serial++;
2555
2556 /* If we are sending a new ASCONF_ACK hold a reference to it in assoc
2557 * after freeing the reference to old asconf ack if any.
2558 */
2559 if (asconf_ack) {
2560 if (asoc->addip_last_asconf_ack)
2561 sctp_chunk_free(asoc->addip_last_asconf_ack);
2562
2563 sctp_chunk_hold(asconf_ack);
2564 asoc->addip_last_asconf_ack = asconf_ack;
2565 }
2566
2567 return asconf_ack;
2568}
2569
2570/* Process a asconf parameter that is successfully acked. */
2571static int sctp_asconf_param_success(struct sctp_association *asoc,
2572 sctp_addip_param_t *asconf_param)
2573{
2574 struct sctp_af *af;
2575 union sctp_addr addr;
2576 struct sctp_bind_addr *bp = &asoc->base.bind_addr;
2577 union sctp_addr_param *addr_param;
2578 struct list_head *pos;
2579 struct sctp_transport *transport;
dc022a98 2580 struct sctp_sockaddr_entry *saddr;
1da177e4
LT		 2581 int retval = 0;
2582
2583 addr_param = (union sctp_addr_param *)
2584 ((void *)asconf_param + sizeof(sctp_addip_param_t));
2585
2586 /* We have checked the packet before, so we do not check again. */
2587 af = sctp_get_af_specific(param_type2af(addr_param->v4.param_hdr.type));
dd86d136 2588 af->from_addr_param(&addr, addr_param, htons(bp->port), 0);
1da177e4
LT		 2589
2590 switch (asconf_param->param_hdr.type) {
2591 case SCTP_PARAM_ADD_IP:
2592 sctp_local_bh_disable();
2593 sctp_write_lock(&asoc->base.addr_lock);
dc022a98
SS		 2594 list_for_each(pos, &bp->address_list) {
2595 saddr = list_entry(pos, struct sctp_sockaddr_entry, list);
dd86d136 2596 if (sctp_cmp_addr_exact(&saddr->a, &addr))
dc022a98
SS		 2597 saddr->use_as_src = 1;
2598 }
1da177e4
LT		 2599 sctp_write_unlock(&asoc->base.addr_lock);
2600 sctp_local_bh_enable();
2601 break;
2602 case SCTP_PARAM_DEL_IP:
2603 sctp_local_bh_disable();
2604 sctp_write_lock(&asoc->base.addr_lock);
dd86d136 2605 retval = sctp_del_bind_addr(bp, &addr);
1da177e4
LT		 2606 sctp_write_unlock(&asoc->base.addr_lock);
2607 sctp_local_bh_enable();
2608 list_for_each(pos, &asoc->peer.transport_addr_list) {
2609 transport = list_entry(pos, struct sctp_transport,
2610 transports);
dc022a98 2611 dst_release(transport->dst);
1da177e4
LT		 2612 sctp_transport_route(transport, NULL,
2613 sctp_sk(asoc->base.sk));
2614 }
2615 break;
2616 default:
2617 break;
2618 }
2619
2620 return retval;
2621}
2622
2623/* Get the corresponding ASCONF response error code from the ASCONF_ACK chunk
2624 * for the given asconf parameter. If there is no response for this parameter,
2625 * return the error code based on the third argument 'no_err'.
2626 * ADDIP 4.1
2627 * A7) If an error response is received for a TLV parameter, all TLVs with no
2628 * response before the failed TLV are considered successful if not reported.
2629 * All TLVs after the failed response are considered unsuccessful unless a
2630 * specific success indication is present for the parameter.
2631 */
dbc16db1 2632static __be16 sctp_get_asconf_response(struct sctp_chunk *asconf_ack,
1da177e4
LT		 2633 sctp_addip_param_t *asconf_param,
2634 int no_err)
2635{
2636 sctp_addip_param_t *asconf_ack_param;
2637 sctp_errhdr_t *err_param;
2638 int length;
2639 int asconf_ack_len = asconf_ack->skb->len;
dbc16db1 2640 __be16 err_code;
1da177e4
LT		 2641
2642 if (no_err)
2643 err_code = SCTP_ERROR_NO_ERROR;
2644 else
2645 err_code = SCTP_ERROR_REQ_REFUSED;
2646
2647 /* Skip the addiphdr from the asconf_ack chunk and store a pointer to
2648 * the first asconf_ack parameter.
2649 */
2650 length = sizeof(sctp_addiphdr_t);
2651 asconf_ack_param = (sctp_addip_param_t *)(asconf_ack->skb->data +
2652 length);
2653 asconf_ack_len -= length;
2654
2655 while (asconf_ack_len > 0) {
2656 if (asconf_ack_param->crr_id == asconf_param->crr_id) {
2657 switch(asconf_ack_param->param_hdr.type) {
2658 case SCTP_PARAM_SUCCESS_REPORT:
2659 return SCTP_ERROR_NO_ERROR;
2660 case SCTP_PARAM_ERR_CAUSE:
2661 length = sizeof(sctp_addip_param_t);
2662 err_param = (sctp_errhdr_t *)
2663 ((void *)asconf_ack_param + length);
2664 asconf_ack_len -= length;
2665 if (asconf_ack_len > 0)
2666 return err_param->cause;
2667 else
2668 return SCTP_ERROR_INV_PARAM;
2669 break;
2670 default:
2671 return SCTP_ERROR_INV_PARAM;
2672 }
2673 }
2674
2675 length = ntohs(asconf_ack_param->param_hdr.length);
2676 asconf_ack_param = (sctp_addip_param_t *)
2677 ((void *)asconf_ack_param + length);
2678 asconf_ack_len -= length;
2679 }
2680
2681 return err_code;
2682}
2683
2684/* Process an incoming ASCONF_ACK chunk against the cached last ASCONF chunk. */
2685int sctp_process_asconf_ack(struct sctp_association *asoc,
2686 struct sctp_chunk *asconf_ack)
2687{
2688 struct sctp_chunk *asconf = asoc->addip_last_asconf;
2689 union sctp_addr_param *addr_param;
2690 sctp_addip_param_t *asconf_param;
2691 int length = 0;
2692 int asconf_len = asconf->skb->len;
2693 int all_param_pass = 0;
2694 int no_err = 1;
2695 int retval = 0;
dbc16db1 2696 __be16 err_code = SCTP_ERROR_NO_ERROR;
1da177e4
LT		 2697
2698 /* Skip the chunkhdr and addiphdr from the last asconf sent and store
2699 * a pointer to address parameter.
2700 */
2701 length = sizeof(sctp_addip_chunk_t);
2702 addr_param = (union sctp_addr_param *)(asconf->skb->data + length);
2703 asconf_len -= length;
2704
2705 /* Skip the address parameter in the last asconf sent and store a
2706 * pointer to the first asconf paramter.
2707 */
2708 length = ntohs(addr_param->v4.param_hdr.length);
2709 asconf_param = (sctp_addip_param_t *)((void *)addr_param + length);
2710 asconf_len -= length;
2711
2712 /* ADDIP 4.1
2713 * A8) If there is no response(s) to specific TLV parameter(s), and no
2714 * failures are indicated, then all request(s) are considered
2715 * successful.
2716 */
2717 if (asconf_ack->skb->len == sizeof(sctp_addiphdr_t))
2718 all_param_pass = 1;
2719
2720 /* Process the TLVs contained in the last sent ASCONF chunk. */
2721 while (asconf_len > 0) {
2722 if (all_param_pass)
2723 err_code = SCTP_ERROR_NO_ERROR;
2724 else {
2725 err_code = sctp_get_asconf_response(asconf_ack,
2726 asconf_param,
2727 no_err);
2728 if (no_err && (SCTP_ERROR_NO_ERROR != err_code))
2729 no_err = 0;
2730 }
2731
2732 switch (err_code) {
2733 case SCTP_ERROR_NO_ERROR:
2734 retval = sctp_asconf_param_success(asoc, asconf_param);
2735 break;
2736
2737 case SCTP_ERROR_RSRC_LOW:
2738 retval = 1;
2739 break;
2740
2741 case SCTP_ERROR_INV_PARAM:
2742 /* Disable sending this type of asconf parameter in
2743 * future.
2744 */
2745 asoc->peer.addip_disabled_mask |=
2746 asconf_param->param_hdr.type;
2747 break;
2748
2749 case SCTP_ERROR_REQ_REFUSED:
2750 case SCTP_ERROR_DEL_LAST_IP:
2751 case SCTP_ERROR_DEL_SRC_IP:
2752 default:
2753 break;
2754 }
2755
2756 /* Skip the processed asconf parameter and move to the next
2757 * one.
2758 */
2759 length = ntohs(asconf_param->param_hdr.length);
2760 asconf_param = (sctp_addip_param_t *)((void *)asconf_param +
2761 length);
2762 asconf_len -= length;
2763 }
2764
2765 /* Free the cached last sent asconf chunk. */
2766 sctp_chunk_free(asconf);
2767 asoc->addip_last_asconf = NULL;
2768
2769 /* Send the next asconf chunk from the addip chunk queue. */
79af02c2
DM		 2770 if (!list_empty(&asoc->addip_chunk_list)) {
2771 struct list_head *entry = asoc->addip_chunk_list.next;
2772 asconf = list_entry(entry, struct sctp_chunk, list);
2773
2774 list_del_init(entry);
2775
1da177e4
LT		 2776 /* Hold the chunk until an ASCONF_ACK is received. */
2777 sctp_chunk_hold(asconf);
2778 if (sctp_primitive_ASCONF(asoc, asconf))
2779 sctp_chunk_free(asconf);
2780 else
2781 asoc->addip_last_asconf = asconf;
2782 }
2783
2784 return retval;
2785}
2786
2787/* Make a FWD TSN chunk. */
2788struct sctp_chunk *sctp_make_fwdtsn(const struct sctp_association *asoc,
2789 __u32 new_cum_tsn, size_t nstreams,
2790 struct sctp_fwdtsn_skip *skiplist)
2791{
2792 struct sctp_chunk *retval = NULL;
2793 struct sctp_fwdtsn_chunk *ftsn_chunk;
2794 struct sctp_fwdtsn_hdr ftsn_hdr;
2795 struct sctp_fwdtsn_skip skip;
2796 size_t hint;
2797 int i;
2798
2799 hint = (nstreams + 1) * sizeof(__u32);
2800
1da177e4
LT		 2801 retval = sctp_make_chunk(asoc, SCTP_CID_FWD_TSN, 0, hint);
2802
2803 if (!retval)
2804 return NULL;
2805
2806 ftsn_chunk = (struct sctp_fwdtsn_chunk *)retval->subh.fwdtsn_hdr;
2807
2808 ftsn_hdr.new_cum_tsn = htonl(new_cum_tsn);
2809 retval->subh.fwdtsn_hdr =
2810 sctp_addto_chunk(retval, sizeof(ftsn_hdr), &ftsn_hdr);
2811
2812 for (i = 0; i < nstreams; i++) {
2813 skip.stream = skiplist[i].stream;
2814 skip.ssn = skiplist[i].ssn;
2815 sctp_addto_chunk(retval, sizeof(skip), &skip);
2816 }
2817
2818 return retval;
2819}
Linux kernel - Deliverables
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