blob: 33ac8bf47b0e0d64b2ba9a75b136bc82eac1fa65 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/* SCTP kernel reference Implementation
2 * (C) Copyright IBM Corp. 2001, 2004
3 * Copyright (c) 1999-2000 Cisco, Inc.
4 * Copyright (c) 1999-2001 Motorola, Inc.
5 * Copyright (c) 2001-2002 Intel Corp.
6 *
7 * This file is part of the SCTP kernel reference Implementation
8 *
9 * These functions work with the state functions in sctp_sm_statefuns.c
10 * to implement the state operations. These functions implement the
11 * steps which require modifying existing data structures.
12 *
13 * The SCTP reference implementation is free software;
14 * you can redistribute it and/or modify it under the terms of
15 * the GNU General Public License as published by
16 * the Free Software Foundation; either version 2, or (at your option)
17 * any later version.
18 *
19 * The SCTP reference implementation is distributed in the hope that it
20 * will be useful, but WITHOUT ANY WARRANTY; without even the implied
21 * ************************
22 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
23 * See the GNU General Public License for more details.
24 *
25 * You should have received a copy of the GNU General Public License
26 * along with GNU CC; see the file COPYING. If not, write to
27 * the Free Software Foundation, 59 Temple Place - Suite 330,
28 * Boston, MA 02111-1307, USA.
29 *
30 * Please send any bug reports or fixes you make to the
31 * email address(es):
32 * lksctp developers <lksctp-developers@lists.sourceforge.net>
33 *
34 * Or submit a bug report through the following website:
35 * http://www.sf.net/projects/lksctp
36 *
37 * Written or modified by:
38 * La Monte H.P. Yarroll <piggy@acm.org>
39 * Karl Knutson <karl@athena.chicago.il.us>
40 * C. Robin <chris@hundredacre.ac.uk>
41 * Jon Grimm <jgrimm@us.ibm.com>
42 * Xingang Guo <xingang.guo@intel.com>
43 * Dajiang Zhang <dajiang.zhang@nokia.com>
44 * Sridhar Samudrala <sri@us.ibm.com>
45 * Daisy Chang <daisyc@us.ibm.com>
46 * Ardelle Fan <ardelle.fan@intel.com>
47 * Kevin Gao <kevin.gao@intel.com>
48 *
49 * Any bugs reported given to us we will try to fix... any fixes shared will
50 * be incorporated into the next SCTP release.
51 */
52
53#include <linux/types.h>
54#include <linux/kernel.h>
55#include <linux/ip.h>
56#include <linux/ipv6.h>
57#include <linux/net.h>
58#include <linux/inet.h>
59#include <asm/scatterlist.h>
60#include <linux/crypto.h>
61#include <net/sock.h>
62
63#include <linux/skbuff.h>
64#include <linux/random.h> /* for get_random_bytes */
65#include <net/sctp/sctp.h>
66#include <net/sctp/sm.h>
67
68extern kmem_cache_t *sctp_chunk_cachep;
69
70SCTP_STATIC
71struct sctp_chunk *sctp_make_chunk(const struct sctp_association *asoc,
72 __u8 type, __u8 flags, int paylen);
73static sctp_cookie_param_t *sctp_pack_cookie(const struct sctp_endpoint *ep,
74 const struct sctp_association *asoc,
75 const struct sctp_chunk *init_chunk,
76 int *cookie_len,
77 const __u8 *raw_addrs, int addrs_len);
78static int sctp_process_param(struct sctp_association *asoc,
79 union sctp_params param,
80 const union sctp_addr *peer_addr,
81 int gfp);
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 */
114void sctp_init_cause(struct sctp_chunk *chunk, __u16 cause_code,
115 const void *payload, size_t paylen)
116{
117 sctp_errhdr_t err;
118 int padlen;
119 __u16 len;
120
121 /* Cause code constants are now defined in network order. */
122 err.cause = cause_code;
123 len = sizeof(sctp_errhdr_t) + paylen;
124 padlen = len % 4;
125 err.length = htons(len);
126 len += padlen;
127 sctp_addto_chunk(chunk, sizeof(sctp_errhdr_t), &err);
128 chunk->subh.err_hdr = sctp_addto_chunk(chunk, paylen, payload);
129}
130
131/* 3.3.2 Initiation (INIT) (1)
132 *
133 * This chunk is used to initiate a SCTP association between two
134 * endpoints. The format of the INIT chunk is shown below:
135 *
136 * 0 1 2 3
137 * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
138 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
139 * | Type = 1 | Chunk Flags | Chunk Length |
140 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
141 * | Initiate Tag |
142 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
143 * | Advertised Receiver Window Credit (a_rwnd) |
144 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
145 * | Number of Outbound Streams | Number of Inbound Streams |
146 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
147 * | Initial TSN |
148 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
149 * \ \
150 * / Optional/Variable-Length Parameters /
151 * \ \
152 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
153 *
154 *
155 * The INIT chunk contains the following parameters. Unless otherwise
156 * noted, each parameter MUST only be included once in the INIT chunk.
157 *
158 * Fixed Parameters Status
159 * ----------------------------------------------
160 * Initiate Tag Mandatory
161 * Advertised Receiver Window Credit Mandatory
162 * Number of Outbound Streams Mandatory
163 * Number of Inbound Streams Mandatory
164 * Initial TSN Mandatory
165 *
166 * Variable Parameters Status Type Value
167 * -------------------------------------------------------------
168 * IPv4 Address (Note 1) Optional 5
169 * IPv6 Address (Note 1) Optional 6
170 * Cookie Preservative Optional 9
171 * Reserved for ECN Capable (Note 2) Optional 32768 (0x8000)
172 * Host Name Address (Note 3) Optional 11
173 * Supported Address Types (Note 4) Optional 12
174 */
175struct sctp_chunk *sctp_make_init(const struct sctp_association *asoc,
176 const struct sctp_bind_addr *bp,
177 int gfp, int vparam_len)
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;
186 __u16 types[2];
187 sctp_adaption_ind_param_t aiparam;
188
189 /* RFC 2960 3.3.2 Initiation (INIT) (1)
190 *
191 * Note 1: The INIT chunks can contain multiple addresses that
192 * can be IPv4 and/or IPv6 in any combination.
193 */
194 retval = NULL;
195
196 /* Convert the provided bind address list to raw format. */
197 addrs = sctp_bind_addrs_to_raw(bp, &addrs_len, gfp);
198
199 init.init_tag = htonl(asoc->c.my_vtag);
200 init.a_rwnd = htonl(asoc->rwnd);
201 init.num_outbound_streams = htons(asoc->c.sinit_num_ostreams);
202 init.num_inbound_streams = htons(asoc->c.sinit_max_instreams);
203 init.initial_tsn = htonl(asoc->c.initial_tsn);
204
205 /* How many address types are needed? */
206 sp = sctp_sk(asoc->base.sk);
207 num_types = sp->pf->supported_addrs(sp, types);
208
209 chunksize = sizeof(init) + addrs_len + SCTP_SAT_LEN(num_types);
210 chunksize += sizeof(ecap_param);
211 if (sctp_prsctp_enable)
212 chunksize += sizeof(prsctp_param);
213 chunksize += sizeof(aiparam);
214 chunksize += vparam_len;
215
216 /* RFC 2960 3.3.2 Initiation (INIT) (1)
217 *
218 * Note 3: An INIT chunk MUST NOT contain more than one Host
219 * Name address parameter. Moreover, the sender of the INIT
220 * MUST NOT combine any other address types with the Host Name
221 * address in the INIT. The receiver of INIT MUST ignore any
222 * other address types if the Host Name address parameter is
223 * present in the received INIT chunk.
224 *
225 * PLEASE DO NOT FIXME [This version does not support Host Name.]
226 */
227
228 retval = sctp_make_chunk(asoc, SCTP_CID_INIT, 0, chunksize);
229 if (!retval)
230 goto nodata;
231
232 retval->subh.init_hdr =
233 sctp_addto_chunk(retval, sizeof(init), &init);
234 retval->param_hdr.v =
235 sctp_addto_chunk(retval, addrs_len, addrs.v);
236
237 /* RFC 2960 3.3.2 Initiation (INIT) (1)
238 *
239 * Note 4: This parameter, when present, specifies all the
240 * address types the sending endpoint can support. The absence
241 * of this parameter indicates that the sending endpoint can
242 * support any address type.
243 */
244 sat.param_hdr.type = SCTP_PARAM_SUPPORTED_ADDRESS_TYPES;
245 sat.param_hdr.length = htons(SCTP_SAT_LEN(num_types));
246 sctp_addto_chunk(retval, sizeof(sat), &sat);
247 sctp_addto_chunk(retval, num_types * sizeof(__u16), &types);
248
249 sctp_addto_chunk(retval, sizeof(ecap_param), &ecap_param);
250 if (sctp_prsctp_enable)
251 sctp_addto_chunk(retval, sizeof(prsctp_param), &prsctp_param);
252 aiparam.param_hdr.type = SCTP_PARAM_ADAPTION_LAYER_IND;
253 aiparam.param_hdr.length = htons(sizeof(aiparam));
254 aiparam.adaption_ind = htonl(sp->adaption_ind);
255 sctp_addto_chunk(retval, sizeof(aiparam), &aiparam);
256nodata:
257 if (addrs.v)
258 kfree(addrs.v);
259 return retval;
260}
261
262struct sctp_chunk *sctp_make_init_ack(const struct sctp_association *asoc,
263 const struct sctp_chunk *chunk,
264 int gfp, int unkparam_len)
265{
266 sctp_inithdr_t initack;
267 struct sctp_chunk *retval;
268 union sctp_params addrs;
269 int addrs_len;
270 sctp_cookie_param_t *cookie;
271 int cookie_len;
272 size_t chunksize;
273 sctp_adaption_ind_param_t aiparam;
274
275 retval = NULL;
276
277 /* Note: there may be no addresses to embed. */
278 addrs = sctp_bind_addrs_to_raw(&asoc->base.bind_addr, &addrs_len, gfp);
279
280 initack.init_tag = htonl(asoc->c.my_vtag);
281 initack.a_rwnd = htonl(asoc->rwnd);
282 initack.num_outbound_streams = htons(asoc->c.sinit_num_ostreams);
283 initack.num_inbound_streams = htons(asoc->c.sinit_max_instreams);
284 initack.initial_tsn = htonl(asoc->c.initial_tsn);
285
286 /* FIXME: We really ought to build the cookie right
287 * into the packet instead of allocating more fresh memory.
288 */
289 cookie = sctp_pack_cookie(asoc->ep, asoc, chunk, &cookie_len,
290 addrs.v, addrs_len);
291 if (!cookie)
292 goto nomem_cookie;
293
294 /* Calculate the total size of allocation, include the reserved
295 * space for reporting unknown parameters if it is specified.
296 */
297 chunksize = sizeof(initack) + addrs_len + cookie_len + unkparam_len;
298
299 /* Tell peer that we'll do ECN only if peer advertised such cap. */
300 if (asoc->peer.ecn_capable)
301 chunksize += sizeof(ecap_param);
302
303 /* Tell peer that we'll do PR-SCTP only if peer advertised. */
304 if (asoc->peer.prsctp_capable)
305 chunksize += sizeof(prsctp_param);
306
307 chunksize += sizeof(aiparam);
308
309 /* Now allocate and fill out the chunk. */
310 retval = sctp_make_chunk(asoc, SCTP_CID_INIT_ACK, 0, chunksize);
311 if (!retval)
312 goto nomem_chunk;
313
314 /* Per the advice in RFC 2960 6.4, send this reply to
315 * the source of the INIT packet.
316 */
317 retval->transport = chunk->transport;
318 retval->subh.init_hdr =
319 sctp_addto_chunk(retval, sizeof(initack), &initack);
320 retval->param_hdr.v = sctp_addto_chunk(retval, addrs_len, addrs.v);
321 sctp_addto_chunk(retval, cookie_len, cookie);
322 if (asoc->peer.ecn_capable)
323 sctp_addto_chunk(retval, sizeof(ecap_param), &ecap_param);
324 if (asoc->peer.prsctp_capable)
325 sctp_addto_chunk(retval, sizeof(prsctp_param), &prsctp_param);
326
327 aiparam.param_hdr.type = SCTP_PARAM_ADAPTION_LAYER_IND;
328 aiparam.param_hdr.length = htons(sizeof(aiparam));
329 aiparam.adaption_ind = htonl(sctp_sk(asoc->base.sk)->adaption_ind);
330 sctp_addto_chunk(retval, sizeof(aiparam), &aiparam);
331
332 /* We need to remove the const qualifier at this point. */
333 retval->asoc = (struct sctp_association *) asoc;
334
335 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
336 *
337 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
338 * HEARTBEAT ACK, * etc.) to the same destination transport
339 * address from which it received the DATA or control chunk
340 * to which it is replying.
341 *
342 * [INIT ACK back to where the INIT came from.]
343 */
344 if (chunk)
345 retval->transport = chunk->transport;
346
347nomem_chunk:
348 kfree(cookie);
349nomem_cookie:
350 if (addrs.v)
351 kfree(addrs.v);
352 return retval;
353}
354
355/* 3.3.11 Cookie Echo (COOKIE ECHO) (10):
356 *
357 * This chunk is used only during the initialization of an association.
358 * It is sent by the initiator of an association to its peer to complete
359 * the initialization process. This chunk MUST precede any DATA chunk
360 * sent within the association, but MAY be bundled with one or more DATA
361 * chunks in the same packet.
362 *
363 * 0 1 2 3
364 * 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
365 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
366 * | Type = 10 |Chunk Flags | Length |
367 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
368 * / Cookie /
369 * \ \
370 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
371 *
372 * Chunk Flags: 8 bit
373 *
374 * Set to zero on transmit and ignored on receipt.
375 *
376 * Length: 16 bits (unsigned integer)
377 *
378 * Set to the size of the chunk in bytes, including the 4 bytes of
379 * the chunk header and the size of the Cookie.
380 *
381 * Cookie: variable size
382 *
383 * This field must contain the exact cookie received in the
384 * State Cookie parameter from the previous INIT ACK.
385 *
386 * An implementation SHOULD make the cookie as small as possible
387 * to insure interoperability.
388 */
389struct sctp_chunk *sctp_make_cookie_echo(const struct sctp_association *asoc,
390 const struct sctp_chunk *chunk)
391{
392 struct sctp_chunk *retval;
393 void *cookie;
394 int cookie_len;
395
396 cookie = asoc->peer.cookie;
397 cookie_len = asoc->peer.cookie_len;
398
399 /* Build a cookie echo chunk. */
400 retval = sctp_make_chunk(asoc, SCTP_CID_COOKIE_ECHO, 0, cookie_len);
401 if (!retval)
402 goto nodata;
403 retval->subh.cookie_hdr =
404 sctp_addto_chunk(retval, cookie_len, cookie);
405
406 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
407 *
408 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
409 * HEARTBEAT ACK, * etc.) to the same destination transport
410 * address from which it * received the DATA or control chunk
411 * to which it is replying.
412 *
413 * [COOKIE ECHO back to where the INIT ACK came from.]
414 */
415 if (chunk)
416 retval->transport = chunk->transport;
417
418nodata:
419 return retval;
420}
421
422/* 3.3.12 Cookie Acknowledgement (COOKIE ACK) (11):
423 *
424 * This chunk is used only during the initialization of an
425 * association. It is used to acknowledge the receipt of a COOKIE
426 * ECHO chunk. This chunk MUST precede any DATA or SACK chunk sent
427 * within the association, but MAY be bundled with one or more DATA
428 * chunks or SACK chunk in the same SCTP packet.
429 *
430 * 0 1 2 3
431 * 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
432 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
433 * | Type = 11 |Chunk Flags | Length = 4 |
434 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
435 *
436 * Chunk Flags: 8 bits
437 *
438 * Set to zero on transmit and ignored on receipt.
439 */
440struct sctp_chunk *sctp_make_cookie_ack(const struct sctp_association *asoc,
441 const struct sctp_chunk *chunk)
442{
443 struct sctp_chunk *retval;
444
445 retval = sctp_make_chunk(asoc, SCTP_CID_COOKIE_ACK, 0, 0);
446
447 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
448 *
449 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
450 * HEARTBEAT ACK, * etc.) to the same destination transport
451 * address from which it * received the DATA or control chunk
452 * to which it is replying.
453 *
454 * [COOKIE ACK back to where the COOKIE ECHO came from.]
455 */
456 if (retval && chunk)
457 retval->transport = chunk->transport;
458
459 return retval;
460}
461
462/*
463 * Appendix A: Explicit Congestion Notification:
464 * CWR:
465 *
466 * RFC 2481 details a specific bit for a sender to send in the header of
467 * its next outbound TCP segment to indicate to its peer that it has
468 * reduced its congestion window. This is termed the CWR bit. For
469 * SCTP the same indication is made by including the CWR chunk.
470 * This chunk contains one data element, i.e. the TSN number that
471 * was sent in the ECNE chunk. This element represents the lowest
472 * TSN number in the datagram that was originally marked with the
473 * CE bit.
474 *
475 * 0 1 2 3
476 * 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
477 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
478 * | Chunk Type=13 | Flags=00000000| Chunk Length = 8 |
479 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
480 * | Lowest TSN Number |
481 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
482 *
483 * Note: The CWR is considered a Control chunk.
484 */
485struct sctp_chunk *sctp_make_cwr(const struct sctp_association *asoc,
486 const __u32 lowest_tsn,
487 const struct sctp_chunk *chunk)
488{
489 struct sctp_chunk *retval;
490 sctp_cwrhdr_t cwr;
491
492 cwr.lowest_tsn = htonl(lowest_tsn);
493 retval = sctp_make_chunk(asoc, SCTP_CID_ECN_CWR, 0,
494 sizeof(sctp_cwrhdr_t));
495
496 if (!retval)
497 goto nodata;
498
499 retval->subh.ecn_cwr_hdr =
500 sctp_addto_chunk(retval, sizeof(cwr), &cwr);
501
502 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
503 *
504 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
505 * HEARTBEAT ACK, * etc.) to the same destination transport
506 * address from which it * received the DATA or control chunk
507 * to which it is replying.
508 *
509 * [Report a reduced congestion window back to where the ECNE
510 * came from.]
511 */
512 if (chunk)
513 retval->transport = chunk->transport;
514
515nodata:
516 return retval;
517}
518
519/* Make an ECNE chunk. This is a congestion experienced report. */
520struct sctp_chunk *sctp_make_ecne(const struct sctp_association *asoc,
521 const __u32 lowest_tsn)
522{
523 struct sctp_chunk *retval;
524 sctp_ecnehdr_t ecne;
525
526 ecne.lowest_tsn = htonl(lowest_tsn);
527 retval = sctp_make_chunk(asoc, SCTP_CID_ECN_ECNE, 0,
528 sizeof(sctp_ecnehdr_t));
529 if (!retval)
530 goto nodata;
531 retval->subh.ecne_hdr =
532 sctp_addto_chunk(retval, sizeof(ecne), &ecne);
533
534nodata:
535 return retval;
536}
537
538/* Make a DATA chunk for the given association from the provided
539 * parameters. However, do not populate the data payload.
540 */
541struct sctp_chunk *sctp_make_datafrag_empty(struct sctp_association *asoc,
542 const struct sctp_sndrcvinfo *sinfo,
543 int data_len, __u8 flags, __u16 ssn)
544{
545 struct sctp_chunk *retval;
546 struct sctp_datahdr dp;
547 int chunk_len;
548
549 /* We assign the TSN as LATE as possible, not here when
550 * creating the chunk.
551 */
552 dp.tsn = 0;
553 dp.stream = htons(sinfo->sinfo_stream);
554 dp.ppid = sinfo->sinfo_ppid;
555
556 /* Set the flags for an unordered send. */
557 if (sinfo->sinfo_flags & MSG_UNORDERED) {
558 flags |= SCTP_DATA_UNORDERED;
559 dp.ssn = 0;
560 } else
561 dp.ssn = htons(ssn);
562
563 chunk_len = sizeof(dp) + data_len;
564 retval = sctp_make_chunk(asoc, SCTP_CID_DATA, flags, chunk_len);
565 if (!retval)
566 goto nodata;
567
568 retval->subh.data_hdr = sctp_addto_chunk(retval, sizeof(dp), &dp);
569 memcpy(&retval->sinfo, sinfo, sizeof(struct sctp_sndrcvinfo));
570
571nodata:
572 return retval;
573}
574
575/* Create a selective ackowledgement (SACK) for the given
576 * association. This reports on which TSN's we've seen to date,
577 * including duplicates and gaps.
578 */
579struct sctp_chunk *sctp_make_sack(const struct sctp_association *asoc)
580{
581 struct sctp_chunk *retval;
582 struct sctp_sackhdr sack;
583 int len;
584 __u32 ctsn;
585 __u16 num_gabs, num_dup_tsns;
586 struct sctp_tsnmap *map = (struct sctp_tsnmap *)&asoc->peer.tsn_map;
587
588 ctsn = sctp_tsnmap_get_ctsn(map);
589 SCTP_DEBUG_PRINTK("sackCTSNAck sent: 0x%x.\n", ctsn);
590
591 /* How much room is needed in the chunk? */
592 num_gabs = sctp_tsnmap_num_gabs(map);
593 num_dup_tsns = sctp_tsnmap_num_dups(map);
594
595 /* Initialize the SACK header. */
596 sack.cum_tsn_ack = htonl(ctsn);
597 sack.a_rwnd = htonl(asoc->a_rwnd);
598 sack.num_gap_ack_blocks = htons(num_gabs);
599 sack.num_dup_tsns = htons(num_dup_tsns);
600
601 len = sizeof(sack)
602 + sizeof(struct sctp_gap_ack_block) * num_gabs
603 + sizeof(__u32) * num_dup_tsns;
604
605 /* Create the chunk. */
606 retval = sctp_make_chunk(asoc, SCTP_CID_SACK, 0, len);
607 if (!retval)
608 goto nodata;
609
610 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
611 *
612 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
613 * HEARTBEAT ACK, etc.) to the same destination transport
614 * address from which it received the DATA or control chunk to
615 * which it is replying. This rule should also be followed if
616 * the endpoint is bundling DATA chunks together with the
617 * reply chunk.
618 *
619 * However, when acknowledging multiple DATA chunks received
620 * in packets from different source addresses in a single
621 * SACK, the SACK chunk may be transmitted to one of the
622 * destination transport addresses from which the DATA or
623 * control chunks being acknowledged were received.
624 *
625 * [BUG: We do not implement the following paragraph.
626 * Perhaps we should remember the last transport we used for a
627 * SACK and avoid that (if possible) if we have seen any
628 * duplicates. --piggy]
629 *
630 * When a receiver of a duplicate DATA chunk sends a SACK to a
631 * multi- homed endpoint it MAY be beneficial to vary the
632 * destination address and not use the source address of the
633 * DATA chunk. The reason being that receiving a duplicate
634 * from a multi-homed endpoint might indicate that the return
635 * path (as specified in the source address of the DATA chunk)
636 * for the SACK is broken.
637 *
638 * [Send to the address from which we last received a DATA chunk.]
639 */
640 retval->transport = asoc->peer.last_data_from;
641
642 retval->subh.sack_hdr =
643 sctp_addto_chunk(retval, sizeof(sack), &sack);
644
645 /* Add the gap ack block information. */
646 if (num_gabs)
647 sctp_addto_chunk(retval, sizeof(__u32) * num_gabs,
648 sctp_tsnmap_get_gabs(map));
649
650 /* Add the duplicate TSN information. */
651 if (num_dup_tsns)
652 sctp_addto_chunk(retval, sizeof(__u32) * num_dup_tsns,
653 sctp_tsnmap_get_dups(map));
654
655nodata:
656 return retval;
657}
658
659/* Make a SHUTDOWN chunk. */
660struct sctp_chunk *sctp_make_shutdown(const struct sctp_association *asoc,
661 const struct sctp_chunk *chunk)
662{
663 struct sctp_chunk *retval;
664 sctp_shutdownhdr_t shut;
665 __u32 ctsn;
666
667 ctsn = sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map);
668 shut.cum_tsn_ack = htonl(ctsn);
669
670 retval = sctp_make_chunk(asoc, SCTP_CID_SHUTDOWN, 0,
671 sizeof(sctp_shutdownhdr_t));
672 if (!retval)
673 goto nodata;
674
675 retval->subh.shutdown_hdr =
676 sctp_addto_chunk(retval, sizeof(shut), &shut);
677
678 if (chunk)
679 retval->transport = chunk->transport;
680nodata:
681 return retval;
682}
683
684struct sctp_chunk *sctp_make_shutdown_ack(const struct sctp_association *asoc,
685 const struct sctp_chunk *chunk)
686{
687 struct sctp_chunk *retval;
688
689 retval = sctp_make_chunk(asoc, SCTP_CID_SHUTDOWN_ACK, 0, 0);
690
691 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
692 *
693 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
694 * HEARTBEAT ACK, * etc.) to the same destination transport
695 * address from which it * received the DATA or control chunk
696 * to which it is replying.
697 *
698 * [ACK back to where the SHUTDOWN came from.]
699 */
700 if (retval && chunk)
701 retval->transport = chunk->transport;
702
703 return retval;
704}
705
706struct sctp_chunk *sctp_make_shutdown_complete(
707 const struct sctp_association *asoc,
708 const struct sctp_chunk *chunk)
709{
710 struct sctp_chunk *retval;
711 __u8 flags = 0;
712
Jerome Forissier047a2422005-04-28 11:58:43 -0700713 /* Set the T-bit if we have no association (vtag will be
714 * reflected)
715 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700716 flags |= asoc ? 0 : SCTP_CHUNK_FLAG_T;
717
718 retval = sctp_make_chunk(asoc, SCTP_CID_SHUTDOWN_COMPLETE, flags, 0);
719
720 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
721 *
722 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
723 * HEARTBEAT ACK, * etc.) to the same destination transport
724 * address from which it * received the DATA or control chunk
725 * to which it is replying.
726 *
727 * [Report SHUTDOWN COMPLETE back to where the SHUTDOWN ACK
728 * came from.]
729 */
730 if (retval && chunk)
731 retval->transport = chunk->transport;
732
733 return retval;
734}
735
736/* Create an ABORT. Note that we set the T bit if we have no
Jerome Forissier047a2422005-04-28 11:58:43 -0700737 * association, except when responding to an INIT (sctpimpguide 2.41).
Linus Torvalds1da177e2005-04-16 15:20:36 -0700738 */
739struct sctp_chunk *sctp_make_abort(const struct sctp_association *asoc,
740 const struct sctp_chunk *chunk,
741 const size_t hint)
742{
743 struct sctp_chunk *retval;
744 __u8 flags = 0;
745
Jerome Forissier047a2422005-04-28 11:58:43 -0700746 /* Set the T-bit if we have no association and 'chunk' is not
747 * an INIT (vtag will be reflected).
748 */
749 if (!asoc) {
750 if (chunk && chunk->chunk_hdr &&
751 chunk->chunk_hdr->type == SCTP_CID_INIT)
752 flags = 0;
753 else
754 flags = SCTP_CHUNK_FLAG_T;
755 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700756
757 retval = sctp_make_chunk(asoc, SCTP_CID_ABORT, flags, hint);
758
759 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
760 *
761 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
762 * HEARTBEAT ACK, * etc.) to the same destination transport
763 * address from which it * received the DATA or control chunk
764 * to which it is replying.
765 *
766 * [ABORT back to where the offender came from.]
767 */
768 if (retval && chunk)
769 retval->transport = chunk->transport;
770
771 return retval;
772}
773
774/* Helper to create ABORT with a NO_USER_DATA error. */
775struct sctp_chunk *sctp_make_abort_no_data(
776 const struct sctp_association *asoc,
777 const struct sctp_chunk *chunk, __u32 tsn)
778{
779 struct sctp_chunk *retval;
780 __u32 payload;
781
782 retval = sctp_make_abort(asoc, chunk, sizeof(sctp_errhdr_t)
783 + sizeof(tsn));
784
785 if (!retval)
786 goto no_mem;
787
788 /* Put the tsn back into network byte order. */
789 payload = htonl(tsn);
790 sctp_init_cause(retval, SCTP_ERROR_NO_DATA, (const void *)&payload,
791 sizeof(payload));
792
793 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
794 *
795 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
796 * HEARTBEAT ACK, * etc.) to the same destination transport
797 * address from which it * received the DATA or control chunk
798 * to which it is replying.
799 *
800 * [ABORT back to where the offender came from.]
801 */
802 if (chunk)
803 retval->transport = chunk->transport;
804
805no_mem:
806 return retval;
807}
808
809/* Helper to create ABORT with a SCTP_ERROR_USER_ABORT error. */
810struct sctp_chunk *sctp_make_abort_user(const struct sctp_association *asoc,
811 const struct sctp_chunk *chunk,
812 const struct msghdr *msg)
813{
814 struct sctp_chunk *retval;
815 void *payload = NULL, *payoff;
816 size_t paylen = 0;
817 struct iovec *iov = NULL;
818 int iovlen = 0;
819
820 if (msg) {
821 iov = msg->msg_iov;
822 iovlen = msg->msg_iovlen;
823 paylen = get_user_iov_size(iov, iovlen);
824 }
825
826 retval = sctp_make_abort(asoc, chunk, sizeof(sctp_errhdr_t) + paylen);
827 if (!retval)
828 goto err_chunk;
829
830 if (paylen) {
831 /* Put the msg_iov together into payload. */
832 payload = kmalloc(paylen, GFP_ATOMIC);
833 if (!payload)
834 goto err_payload;
835 payoff = payload;
836
837 for (; iovlen > 0; --iovlen) {
838 if (copy_from_user(payoff, iov->iov_base,iov->iov_len))
839 goto err_copy;
840 payoff += iov->iov_len;
841 iov++;
842 }
843 }
844
845 sctp_init_cause(retval, SCTP_ERROR_USER_ABORT, payload, paylen);
846
847 if (paylen)
848 kfree(payload);
849
850 return retval;
851
852err_copy:
853 kfree(payload);
854err_payload:
855 sctp_chunk_free(retval);
856 retval = NULL;
857err_chunk:
858 return retval;
859}
860
861/* Make an ABORT chunk with a PROTOCOL VIOLATION cause code. */
862struct sctp_chunk *sctp_make_abort_violation(
863 const struct sctp_association *asoc,
864 const struct sctp_chunk *chunk,
865 const __u8 *payload,
866 const size_t paylen)
867{
868 struct sctp_chunk *retval;
869 struct sctp_paramhdr phdr;
870
871 retval = sctp_make_abort(asoc, chunk, sizeof(sctp_errhdr_t) + paylen
872 + sizeof(sctp_chunkhdr_t));
873 if (!retval)
874 goto end;
875
876 sctp_init_cause(retval, SCTP_ERROR_PROTO_VIOLATION, payload, paylen);
877
878 phdr.type = htons(chunk->chunk_hdr->type);
879 phdr.length = chunk->chunk_hdr->length;
880 sctp_addto_chunk(retval, sizeof(sctp_paramhdr_t), &phdr);
881
882end:
883 return retval;
884}
885
886/* Make a HEARTBEAT chunk. */
887struct sctp_chunk *sctp_make_heartbeat(const struct sctp_association *asoc,
888 const struct sctp_transport *transport,
889 const void *payload, const size_t paylen)
890{
891 struct sctp_chunk *retval = sctp_make_chunk(asoc, SCTP_CID_HEARTBEAT,
892 0, paylen);
893
894 if (!retval)
895 goto nodata;
896
897 /* Cast away the 'const', as this is just telling the chunk
898 * what transport it belongs to.
899 */
900 retval->transport = (struct sctp_transport *) transport;
901 retval->subh.hbs_hdr = sctp_addto_chunk(retval, paylen, payload);
902
903nodata:
904 return retval;
905}
906
907struct sctp_chunk *sctp_make_heartbeat_ack(const struct sctp_association *asoc,
908 const struct sctp_chunk *chunk,
909 const void *payload, const size_t paylen)
910{
911 struct sctp_chunk *retval;
912
913 retval = sctp_make_chunk(asoc, SCTP_CID_HEARTBEAT_ACK, 0, paylen);
914 if (!retval)
915 goto nodata;
916
917 retval->subh.hbs_hdr = sctp_addto_chunk(retval, paylen, payload);
918
919 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
920 *
921 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
922 * HEARTBEAT ACK, * etc.) to the same destination transport
923 * address from which it * received the DATA or control chunk
924 * to which it is replying.
925 *
926 * [HBACK back to where the HEARTBEAT came from.]
927 */
928 if (chunk)
929 retval->transport = chunk->transport;
930
931nodata:
932 return retval;
933}
934
935/* Create an Operation Error chunk with the specified space reserved.
936 * This routine can be used for containing multiple causes in the chunk.
937 */
938static struct sctp_chunk *sctp_make_op_error_space(
939 const struct sctp_association *asoc,
940 const struct sctp_chunk *chunk,
941 size_t size)
942{
943 struct sctp_chunk *retval;
944
945 retval = sctp_make_chunk(asoc, SCTP_CID_ERROR, 0,
946 sizeof(sctp_errhdr_t) + size);
947 if (!retval)
948 goto nodata;
949
950 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
951 *
952 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
953 * HEARTBEAT ACK, etc.) to the same destination transport
954 * address from which it received the DATA or control chunk
955 * to which it is replying.
956 *
957 */
958 if (chunk)
959 retval->transport = chunk->transport;
960
961nodata:
962 return retval;
963}
964
965/* Create an Operation Error chunk. */
966struct sctp_chunk *sctp_make_op_error(const struct sctp_association *asoc,
967 const struct sctp_chunk *chunk,
968 __u16 cause_code, const void *payload,
969 size_t paylen)
970{
971 struct sctp_chunk *retval;
972
973 retval = sctp_make_op_error_space(asoc, chunk, paylen);
974 if (!retval)
975 goto nodata;
976
977 sctp_init_cause(retval, cause_code, payload, paylen);
978
979nodata:
980 return retval;
981}
982
983/********************************************************************
984 * 2nd Level Abstractions
985 ********************************************************************/
986
987/* Turn an skb into a chunk.
988 * FIXME: Eventually move the structure directly inside the skb->cb[].
989 */
990struct sctp_chunk *sctp_chunkify(struct sk_buff *skb,
991 const struct sctp_association *asoc,
992 struct sock *sk)
993{
994 struct sctp_chunk *retval;
995
996 retval = kmem_cache_alloc(sctp_chunk_cachep, SLAB_ATOMIC);
997
998 if (!retval)
999 goto nodata;
1000 memset(retval, 0, sizeof(struct sctp_chunk));
1001
1002 if (!sk) {
1003 SCTP_DEBUG_PRINTK("chunkifying skb %p w/o an sk\n", skb);
1004 }
1005
1006 retval->skb = skb;
1007 retval->asoc = (struct sctp_association *)asoc;
1008 retval->resent = 0;
1009 retval->has_tsn = 0;
1010 retval->has_ssn = 0;
1011 retval->rtt_in_progress = 0;
1012 retval->sent_at = 0;
1013 retval->singleton = 1;
1014 retval->end_of_packet = 0;
1015 retval->ecn_ce_done = 0;
1016 retval->pdiscard = 0;
1017
1018 /* sctpimpguide-05.txt Section 2.8.2
1019 * M1) Each time a new DATA chunk is transmitted
1020 * set the 'TSN.Missing.Report' count for that TSN to 0. The
1021 * 'TSN.Missing.Report' count will be used to determine missing chunks
1022 * and when to fast retransmit.
1023 */
1024 retval->tsn_missing_report = 0;
1025 retval->tsn_gap_acked = 0;
1026 retval->fast_retransmit = 0;
1027
1028 /* If this is a fragmented message, track all fragments
1029 * of the message (for SEND_FAILED).
1030 */
1031 retval->msg = NULL;
1032
1033 /* Polish the bead hole. */
1034 INIT_LIST_HEAD(&retval->transmitted_list);
1035 INIT_LIST_HEAD(&retval->frag_list);
1036 SCTP_DBG_OBJCNT_INC(chunk);
1037 atomic_set(&retval->refcnt, 1);
1038
1039nodata:
1040 return retval;
1041}
1042
1043/* Set chunk->source and dest based on the IP header in chunk->skb. */
1044void sctp_init_addrs(struct sctp_chunk *chunk, union sctp_addr *src,
1045 union sctp_addr *dest)
1046{
1047 memcpy(&chunk->source, src, sizeof(union sctp_addr));
1048 memcpy(&chunk->dest, dest, sizeof(union sctp_addr));
1049}
1050
1051/* Extract the source address from a chunk. */
1052const union sctp_addr *sctp_source(const struct sctp_chunk *chunk)
1053{
1054 /* If we have a known transport, use that. */
1055 if (chunk->transport) {
1056 return &chunk->transport->ipaddr;
1057 } else {
1058 /* Otherwise, extract it from the IP header. */
1059 return &chunk->source;
1060 }
1061}
1062
1063/* Create a new chunk, setting the type and flags headers from the
1064 * arguments, reserving enough space for a 'paylen' byte payload.
1065 */
1066SCTP_STATIC
1067struct sctp_chunk *sctp_make_chunk(const struct sctp_association *asoc,
1068 __u8 type, __u8 flags, int paylen)
1069{
1070 struct sctp_chunk *retval;
1071 sctp_chunkhdr_t *chunk_hdr;
1072 struct sk_buff *skb;
1073 struct sock *sk;
1074
1075 /* No need to allocate LL here, as this is only a chunk. */
1076 skb = alloc_skb(WORD_ROUND(sizeof(sctp_chunkhdr_t) + paylen),
1077 GFP_ATOMIC);
1078 if (!skb)
1079 goto nodata;
1080
1081 /* Make room for the chunk header. */
1082 chunk_hdr = (sctp_chunkhdr_t *)skb_put(skb, sizeof(sctp_chunkhdr_t));
1083 chunk_hdr->type = type;
1084 chunk_hdr->flags = flags;
1085 chunk_hdr->length = htons(sizeof(sctp_chunkhdr_t));
1086
1087 sk = asoc ? asoc->base.sk : NULL;
1088 retval = sctp_chunkify(skb, asoc, sk);
1089 if (!retval) {
1090 kfree_skb(skb);
1091 goto nodata;
1092 }
1093
1094 retval->chunk_hdr = chunk_hdr;
1095 retval->chunk_end = ((__u8 *)chunk_hdr) + sizeof(struct sctp_chunkhdr);
1096
1097 /* Set the skb to the belonging sock for accounting. */
1098 skb->sk = sk;
1099
1100 return retval;
1101nodata:
1102 return NULL;
1103}
1104
1105
1106/* Release the memory occupied by a chunk. */
1107static void sctp_chunk_destroy(struct sctp_chunk *chunk)
1108{
1109 /* Free the chunk skb data and the SCTP_chunk stub itself. */
1110 dev_kfree_skb(chunk->skb);
1111
1112 SCTP_DBG_OBJCNT_DEC(chunk);
1113 kmem_cache_free(sctp_chunk_cachep, chunk);
1114}
1115
1116/* Possibly, free the chunk. */
1117void sctp_chunk_free(struct sctp_chunk *chunk)
1118{
1119 /* Make sure that we are not on any list. */
1120 skb_unlink((struct sk_buff *) chunk);
1121 list_del_init(&chunk->transmitted_list);
1122
1123 /* Release our reference on the message tracker. */
1124 if (chunk->msg)
1125 sctp_datamsg_put(chunk->msg);
1126
1127 sctp_chunk_put(chunk);
1128}
1129
1130/* Grab a reference to the chunk. */
1131void sctp_chunk_hold(struct sctp_chunk *ch)
1132{
1133 atomic_inc(&ch->refcnt);
1134}
1135
1136/* Release a reference to the chunk. */
1137void sctp_chunk_put(struct sctp_chunk *ch)
1138{
1139 if (atomic_dec_and_test(&ch->refcnt))
1140 sctp_chunk_destroy(ch);
1141}
1142
1143/* Append bytes to the end of a chunk. Will panic if chunk is not big
1144 * enough.
1145 */
1146void *sctp_addto_chunk(struct sctp_chunk *chunk, int len, const void *data)
1147{
1148 void *target;
1149 void *padding;
1150 int chunklen = ntohs(chunk->chunk_hdr->length);
1151 int padlen = chunklen % 4;
1152
1153 padding = skb_put(chunk->skb, padlen);
1154 target = skb_put(chunk->skb, len);
1155
1156 memset(padding, 0, padlen);
1157 memcpy(target, data, len);
1158
1159 /* Adjust the chunk length field. */
1160 chunk->chunk_hdr->length = htons(chunklen + padlen + len);
1161 chunk->chunk_end = chunk->skb->tail;
1162
1163 return target;
1164}
1165
1166/* Append bytes from user space to the end of a chunk. Will panic if
1167 * chunk is not big enough.
1168 * Returns a kernel err value.
1169 */
1170int sctp_user_addto_chunk(struct sctp_chunk *chunk, int off, int len,
1171 struct iovec *data)
1172{
1173 __u8 *target;
1174 int err = 0;
1175
1176 /* Make room in chunk for data. */
1177 target = skb_put(chunk->skb, len);
1178
1179 /* Copy data (whole iovec) into chunk */
1180 if ((err = memcpy_fromiovecend(target, data, off, len)))
1181 goto out;
1182
1183 /* Adjust the chunk length field. */
1184 chunk->chunk_hdr->length =
1185 htons(ntohs(chunk->chunk_hdr->length) + len);
1186 chunk->chunk_end = chunk->skb->tail;
1187
1188out:
1189 return err;
1190}
1191
1192/* Helper function to assign a TSN if needed. This assumes that both
1193 * the data_hdr and association have already been assigned.
1194 */
1195void sctp_chunk_assign_ssn(struct sctp_chunk *chunk)
1196{
1197 __u16 ssn;
1198 __u16 sid;
1199
1200 if (chunk->has_ssn)
1201 return;
1202
1203 /* This is the last possible instant to assign a SSN. */
1204 if (chunk->chunk_hdr->flags & SCTP_DATA_UNORDERED) {
1205 ssn = 0;
1206 } else {
1207 sid = htons(chunk->subh.data_hdr->stream);
1208 if (chunk->chunk_hdr->flags & SCTP_DATA_LAST_FRAG)
1209 ssn = sctp_ssn_next(&chunk->asoc->ssnmap->out, sid);
1210 else
1211 ssn = sctp_ssn_peek(&chunk->asoc->ssnmap->out, sid);
1212 ssn = htons(ssn);
1213 }
1214
1215 chunk->subh.data_hdr->ssn = ssn;
1216 chunk->has_ssn = 1;
1217}
1218
1219/* Helper function to assign a TSN if needed. This assumes that both
1220 * the data_hdr and association have already been assigned.
1221 */
1222void sctp_chunk_assign_tsn(struct sctp_chunk *chunk)
1223{
1224 if (!chunk->has_tsn) {
1225 /* This is the last possible instant to
1226 * assign a TSN.
1227 */
1228 chunk->subh.data_hdr->tsn =
1229 htonl(sctp_association_get_next_tsn(chunk->asoc));
1230 chunk->has_tsn = 1;
1231 }
1232}
1233
1234/* Create a CLOSED association to use with an incoming packet. */
1235struct sctp_association *sctp_make_temp_asoc(const struct sctp_endpoint *ep,
1236 struct sctp_chunk *chunk, int gfp)
1237{
1238 struct sctp_association *asoc;
1239 struct sk_buff *skb;
1240 sctp_scope_t scope;
1241 struct sctp_af *af;
1242
1243 /* Create the bare association. */
1244 scope = sctp_scope(sctp_source(chunk));
1245 asoc = sctp_association_new(ep, ep->base.sk, scope, gfp);
1246 if (!asoc)
1247 goto nodata;
1248 asoc->temp = 1;
1249 skb = chunk->skb;
1250 /* Create an entry for the source address of the packet. */
1251 af = sctp_get_af_specific(ipver2af(skb->nh.iph->version));
1252 if (unlikely(!af))
1253 goto fail;
1254 af->from_skb(&asoc->c.peer_addr, skb, 1);
1255nodata:
1256 return asoc;
1257
1258fail:
1259 sctp_association_free(asoc);
1260 return NULL;
1261}
1262
1263/* Build a cookie representing asoc.
1264 * This INCLUDES the param header needed to put the cookie in the INIT ACK.
1265 */
1266static sctp_cookie_param_t *sctp_pack_cookie(const struct sctp_endpoint *ep,
1267 const struct sctp_association *asoc,
1268 const struct sctp_chunk *init_chunk,
1269 int *cookie_len,
1270 const __u8 *raw_addrs, int addrs_len)
1271{
1272 sctp_cookie_param_t *retval;
1273 struct sctp_signed_cookie *cookie;
1274 struct scatterlist sg;
1275 int headersize, bodysize;
1276 unsigned int keylen;
1277 char *key;
1278
1279 headersize = sizeof(sctp_paramhdr_t) + SCTP_SECRET_SIZE;
1280 bodysize = sizeof(struct sctp_cookie)
1281 + ntohs(init_chunk->chunk_hdr->length) + addrs_len;
1282
1283 /* Pad out the cookie to a multiple to make the signature
1284 * functions simpler to write.
1285 */
1286 if (bodysize % SCTP_COOKIE_MULTIPLE)
1287 bodysize += SCTP_COOKIE_MULTIPLE
1288 - (bodysize % SCTP_COOKIE_MULTIPLE);
1289 *cookie_len = headersize + bodysize;
1290
1291 retval = (sctp_cookie_param_t *)kmalloc(*cookie_len, GFP_ATOMIC);
1292
1293 if (!retval) {
1294 *cookie_len = 0;
1295 goto nodata;
1296 }
1297
1298 /* Clear this memory since we are sending this data structure
1299 * out on the network.
1300 */
1301 memset(retval, 0x00, *cookie_len);
1302 cookie = (struct sctp_signed_cookie *) retval->body;
1303
1304 /* Set up the parameter header. */
1305 retval->p.type = SCTP_PARAM_STATE_COOKIE;
1306 retval->p.length = htons(*cookie_len);
1307
1308 /* Copy the cookie part of the association itself. */
1309 cookie->c = asoc->c;
1310 /* Save the raw address list length in the cookie. */
1311 cookie->c.raw_addr_list_len = addrs_len;
1312
1313 /* Remember PR-SCTP capability. */
1314 cookie->c.prsctp_capable = asoc->peer.prsctp_capable;
1315
1316 /* Save adaption indication in the cookie. */
1317 cookie->c.adaption_ind = asoc->peer.adaption_ind;
1318
1319 /* Set an expiration time for the cookie. */
1320 do_gettimeofday(&cookie->c.expiration);
1321 TIMEVAL_ADD(asoc->cookie_life, cookie->c.expiration);
1322
1323 /* Copy the peer's init packet. */
1324 memcpy(&cookie->c.peer_init[0], init_chunk->chunk_hdr,
1325 ntohs(init_chunk->chunk_hdr->length));
1326
1327 /* Copy the raw local address list of the association. */
1328 memcpy((__u8 *)&cookie->c.peer_init[0] +
1329 ntohs(init_chunk->chunk_hdr->length), raw_addrs, addrs_len);
1330
1331 if (sctp_sk(ep->base.sk)->hmac) {
1332 /* Sign the message. */
1333 sg.page = virt_to_page(&cookie->c);
1334 sg.offset = (unsigned long)(&cookie->c) % PAGE_SIZE;
1335 sg.length = bodysize;
1336 keylen = SCTP_SECRET_SIZE;
1337 key = (char *)ep->secret_key[ep->current_key];
1338
1339 sctp_crypto_hmac(sctp_sk(ep->base.sk)->hmac, key, &keylen,
1340 &sg, 1, cookie->signature);
1341 }
1342
1343nodata:
1344 return retval;
1345}
1346
1347/* Unpack the cookie from COOKIE ECHO chunk, recreating the association. */
1348struct sctp_association *sctp_unpack_cookie(
1349 const struct sctp_endpoint *ep,
1350 const struct sctp_association *asoc,
1351 struct sctp_chunk *chunk, int gfp,
1352 int *error, struct sctp_chunk **errp)
1353{
1354 struct sctp_association *retval = NULL;
1355 struct sctp_signed_cookie *cookie;
1356 struct sctp_cookie *bear_cookie;
1357 int headersize, bodysize, fixed_size;
1358 __u8 digest[SCTP_SIGNATURE_SIZE];
1359 struct scatterlist sg;
1360 unsigned int keylen, len;
1361 char *key;
1362 sctp_scope_t scope;
1363 struct sk_buff *skb = chunk->skb;
1364
1365 headersize = sizeof(sctp_chunkhdr_t) + SCTP_SECRET_SIZE;
1366 bodysize = ntohs(chunk->chunk_hdr->length) - headersize;
1367 fixed_size = headersize + sizeof(struct sctp_cookie);
1368
1369 /* Verify that the chunk looks like it even has a cookie.
1370 * There must be enough room for our cookie and our peer's
1371 * INIT chunk.
1372 */
1373 len = ntohs(chunk->chunk_hdr->length);
1374 if (len < fixed_size + sizeof(struct sctp_chunkhdr))
1375 goto malformed;
1376
1377 /* Verify that the cookie has been padded out. */
1378 if (bodysize % SCTP_COOKIE_MULTIPLE)
1379 goto malformed;
1380
1381 /* Process the cookie. */
1382 cookie = chunk->subh.cookie_hdr;
1383 bear_cookie = &cookie->c;
1384
1385 if (!sctp_sk(ep->base.sk)->hmac)
1386 goto no_hmac;
1387
1388 /* Check the signature. */
1389 keylen = SCTP_SECRET_SIZE;
1390 sg.page = virt_to_page(bear_cookie);
1391 sg.offset = (unsigned long)(bear_cookie) % PAGE_SIZE;
1392 sg.length = bodysize;
1393 key = (char *)ep->secret_key[ep->current_key];
1394
1395 memset(digest, 0x00, sizeof(digest));
1396 sctp_crypto_hmac(sctp_sk(ep->base.sk)->hmac, key, &keylen, &sg,
1397 1, digest);
1398
1399 if (memcmp(digest, cookie->signature, SCTP_SIGNATURE_SIZE)) {
1400 /* Try the previous key. */
1401 key = (char *)ep->secret_key[ep->last_key];
1402 memset(digest, 0x00, sizeof(digest));
1403 sctp_crypto_hmac(sctp_sk(ep->base.sk)->hmac, key, &keylen,
1404 &sg, 1, digest);
1405
1406 if (memcmp(digest, cookie->signature, SCTP_SIGNATURE_SIZE)) {
1407 /* Yikes! Still bad signature! */
1408 *error = -SCTP_IERROR_BAD_SIG;
1409 goto fail;
1410 }
1411 }
1412
1413no_hmac:
1414 /* IG Section 2.35.2:
1415 * 3) Compare the port numbers and the verification tag contained
1416 * within the COOKIE ECHO chunk to the actual port numbers and the
1417 * verification tag within the SCTP common header of the received
1418 * packet. If these values do not match the packet MUST be silently
1419 * discarded,
1420 */
1421 if (ntohl(chunk->sctp_hdr->vtag) != bear_cookie->my_vtag) {
1422 *error = -SCTP_IERROR_BAD_TAG;
1423 goto fail;
1424 }
1425
1426 if (ntohs(chunk->sctp_hdr->source) != bear_cookie->peer_addr.v4.sin_port ||
1427 ntohs(chunk->sctp_hdr->dest) != bear_cookie->my_port) {
1428 *error = -SCTP_IERROR_BAD_PORTS;
1429 goto fail;
1430 }
1431
1432 /* Check to see if the cookie is stale. If there is already
1433 * an association, there is no need to check cookie's expiration
1434 * for init collision case of lost COOKIE ACK.
1435 */
1436 if (!asoc && tv_lt(bear_cookie->expiration, skb->stamp)) {
1437 __u16 len;
1438 /*
1439 * Section 3.3.10.3 Stale Cookie Error (3)
1440 *
1441 * Cause of error
1442 * ---------------
1443 * Stale Cookie Error: Indicates the receipt of a valid State
1444 * Cookie that has expired.
1445 */
1446 len = ntohs(chunk->chunk_hdr->length);
1447 *errp = sctp_make_op_error_space(asoc, chunk, len);
1448 if (*errp) {
1449 suseconds_t usecs = (skb->stamp.tv_sec -
1450 bear_cookie->expiration.tv_sec) * 1000000L +
1451 skb->stamp.tv_usec -
1452 bear_cookie->expiration.tv_usec;
1453
1454 usecs = htonl(usecs);
1455 sctp_init_cause(*errp, SCTP_ERROR_STALE_COOKIE,
1456 &usecs, sizeof(usecs));
1457 *error = -SCTP_IERROR_STALE_COOKIE;
1458 } else
1459 *error = -SCTP_IERROR_NOMEM;
1460
1461 goto fail;
1462 }
1463
1464 /* Make a new base association. */
1465 scope = sctp_scope(sctp_source(chunk));
1466 retval = sctp_association_new(ep, ep->base.sk, scope, gfp);
1467 if (!retval) {
1468 *error = -SCTP_IERROR_NOMEM;
1469 goto fail;
1470 }
1471
1472 /* Set up our peer's port number. */
1473 retval->peer.port = ntohs(chunk->sctp_hdr->source);
1474
1475 /* Populate the association from the cookie. */
1476 memcpy(&retval->c, bear_cookie, sizeof(*bear_cookie));
1477
1478 if (sctp_assoc_set_bind_addr_from_cookie(retval, bear_cookie,
1479 GFP_ATOMIC) < 0) {
1480 *error = -SCTP_IERROR_NOMEM;
1481 goto fail;
1482 }
1483
1484 /* Also, add the destination address. */
1485 if (list_empty(&retval->base.bind_addr.address_list)) {
1486 sctp_add_bind_addr(&retval->base.bind_addr, &chunk->dest,
1487 GFP_ATOMIC);
1488 }
1489
1490 retval->next_tsn = retval->c.initial_tsn;
1491 retval->ctsn_ack_point = retval->next_tsn - 1;
1492 retval->addip_serial = retval->c.initial_tsn;
1493 retval->adv_peer_ack_point = retval->ctsn_ack_point;
1494 retval->peer.prsctp_capable = retval->c.prsctp_capable;
1495 retval->peer.adaption_ind = retval->c.adaption_ind;
1496
1497 /* The INIT stuff will be done by the side effects. */
1498 return retval;
1499
1500fail:
1501 if (retval)
1502 sctp_association_free(retval);
1503
1504 return NULL;
1505
1506malformed:
1507 /* Yikes! The packet is either corrupt or deliberately
1508 * malformed.
1509 */
1510 *error = -SCTP_IERROR_MALFORMED;
1511 goto fail;
1512}
1513
1514/********************************************************************
1515 * 3rd Level Abstractions
1516 ********************************************************************/
1517
1518struct __sctp_missing {
1519 __u32 num_missing;
1520 __u16 type;
1521} __attribute__((packed));
1522
1523/*
1524 * Report a missing mandatory parameter.
1525 */
1526static int sctp_process_missing_param(const struct sctp_association *asoc,
1527 sctp_param_t paramtype,
1528 struct sctp_chunk *chunk,
1529 struct sctp_chunk **errp)
1530{
1531 struct __sctp_missing report;
1532 __u16 len;
1533
1534 len = WORD_ROUND(sizeof(report));
1535
1536 /* Make an ERROR chunk, preparing enough room for
1537 * returning multiple unknown parameters.
1538 */
1539 if (!*errp)
1540 *errp = sctp_make_op_error_space(asoc, chunk, len);
1541
1542 if (*errp) {
1543 report.num_missing = htonl(1);
1544 report.type = paramtype;
1545 sctp_init_cause(*errp, SCTP_ERROR_INV_PARAM,
1546 &report, sizeof(report));
1547 }
1548
1549 /* Stop processing this chunk. */
1550 return 0;
1551}
1552
1553/* Report an Invalid Mandatory Parameter. */
1554static int sctp_process_inv_mandatory(const struct sctp_association *asoc,
1555 struct sctp_chunk *chunk,
1556 struct sctp_chunk **errp)
1557{
1558 /* Invalid Mandatory Parameter Error has no payload. */
1559
1560 if (!*errp)
1561 *errp = sctp_make_op_error_space(asoc, chunk, 0);
1562
1563 if (*errp)
1564 sctp_init_cause(*errp, SCTP_ERROR_INV_PARAM, NULL, 0);
1565
1566 /* Stop processing this chunk. */
1567 return 0;
1568}
1569
1570static int sctp_process_inv_paramlength(const struct sctp_association *asoc,
1571 struct sctp_paramhdr *param,
1572 const struct sctp_chunk *chunk,
1573 struct sctp_chunk **errp)
1574{
1575 char error[] = "The following parameter had invalid length:";
1576 size_t payload_len = WORD_ROUND(sizeof(error)) +
1577 sizeof(sctp_paramhdr_t);
1578
1579
1580 /* Create an error chunk and fill it in with our payload. */
1581 if (!*errp)
1582 *errp = sctp_make_op_error_space(asoc, chunk, payload_len);
1583
1584 if (*errp) {
1585 sctp_init_cause(*errp, SCTP_ERROR_PROTO_VIOLATION, error,
1586 sizeof(error));
1587 sctp_addto_chunk(*errp, sizeof(sctp_paramhdr_t), param);
1588 }
1589
1590 return 0;
1591}
1592
1593
1594/* Do not attempt to handle the HOST_NAME parm. However, do
1595 * send back an indicator to the peer.
1596 */
1597static int sctp_process_hn_param(const struct sctp_association *asoc,
1598 union sctp_params param,
1599 struct sctp_chunk *chunk,
1600 struct sctp_chunk **errp)
1601{
1602 __u16 len = ntohs(param.p->length);
1603
1604 /* Make an ERROR chunk. */
1605 if (!*errp)
1606 *errp = sctp_make_op_error_space(asoc, chunk, len);
1607
1608 if (*errp)
1609 sctp_init_cause(*errp, SCTP_ERROR_DNS_FAILED,
1610 param.v, len);
1611
1612 /* Stop processing this chunk. */
1613 return 0;
1614}
1615
1616/* RFC 3.2.1 & the Implementers Guide 2.2.
1617 *
1618 * The Parameter Types are encoded such that the
1619 * highest-order two bits specify the action that must be
1620 * taken if the processing endpoint does not recognize the
1621 * Parameter Type.
1622 *
1623 * 00 - Stop processing this SCTP chunk and discard it,
1624 * do not process any further chunks within it.
1625 *
1626 * 01 - Stop processing this SCTP chunk and discard it,
1627 * do not process any further chunks within it, and report
1628 * the unrecognized parameter in an 'Unrecognized
1629 * Parameter Type' (in either an ERROR or in the INIT ACK).
1630 *
1631 * 10 - Skip this parameter and continue processing.
1632 *
1633 * 11 - Skip this parameter and continue processing but
1634 * report the unrecognized parameter in an
1635 * 'Unrecognized Parameter Type' (in either an ERROR or in
1636 * the INIT ACK).
1637 *
1638 * Return value:
1639 * 0 - discard the chunk
1640 * 1 - continue with the chunk
1641 */
1642static int sctp_process_unk_param(const struct sctp_association *asoc,
1643 union sctp_params param,
1644 struct sctp_chunk *chunk,
1645 struct sctp_chunk **errp)
1646{
1647 int retval = 1;
1648
1649 switch (param.p->type & SCTP_PARAM_ACTION_MASK) {
1650 case SCTP_PARAM_ACTION_DISCARD:
1651 retval = 0;
1652 break;
1653 case SCTP_PARAM_ACTION_DISCARD_ERR:
1654 retval = 0;
1655 /* Make an ERROR chunk, preparing enough room for
1656 * returning multiple unknown parameters.
1657 */
1658 if (NULL == *errp)
1659 *errp = sctp_make_op_error_space(asoc, chunk,
1660 ntohs(chunk->chunk_hdr->length));
1661
1662 if (*errp)
1663 sctp_init_cause(*errp, SCTP_ERROR_UNKNOWN_PARAM,
1664 param.v,
1665 WORD_ROUND(ntohs(param.p->length)));
1666
1667 break;
1668 case SCTP_PARAM_ACTION_SKIP:
1669 break;
1670 case SCTP_PARAM_ACTION_SKIP_ERR:
1671 /* Make an ERROR chunk, preparing enough room for
1672 * returning multiple unknown parameters.
1673 */
1674 if (NULL == *errp)
1675 *errp = sctp_make_op_error_space(asoc, chunk,
1676 ntohs(chunk->chunk_hdr->length));
1677
1678 if (*errp) {
1679 sctp_init_cause(*errp, SCTP_ERROR_UNKNOWN_PARAM,
1680 param.v,
1681 WORD_ROUND(ntohs(param.p->length)));
1682 } else {
1683 /* If there is no memory for generating the ERROR
1684 * report as specified, an ABORT will be triggered
1685 * to the peer and the association won't be
1686 * established.
1687 */
1688 retval = 0;
1689 }
1690
1691 break;
1692 default:
1693 break;
1694 }
1695
1696 return retval;
1697}
1698
1699/* Find unrecognized parameters in the chunk.
1700 * Return values:
1701 * 0 - discard the chunk
1702 * 1 - continue with the chunk
1703 */
1704static int sctp_verify_param(const struct sctp_association *asoc,
1705 union sctp_params param,
1706 sctp_cid_t cid,
1707 struct sctp_chunk *chunk,
1708 struct sctp_chunk **err_chunk)
1709{
1710 int retval = 1;
1711
1712 /* FIXME - This routine is not looking at each parameter per the
1713 * chunk type, i.e., unrecognized parameters should be further
1714 * identified based on the chunk id.
1715 */
1716
1717 switch (param.p->type) {
1718 case SCTP_PARAM_IPV4_ADDRESS:
1719 case SCTP_PARAM_IPV6_ADDRESS:
1720 case SCTP_PARAM_COOKIE_PRESERVATIVE:
1721 case SCTP_PARAM_SUPPORTED_ADDRESS_TYPES:
1722 case SCTP_PARAM_STATE_COOKIE:
1723 case SCTP_PARAM_HEARTBEAT_INFO:
1724 case SCTP_PARAM_UNRECOGNIZED_PARAMETERS:
1725 case SCTP_PARAM_ECN_CAPABLE:
1726 case SCTP_PARAM_ADAPTION_LAYER_IND:
1727 break;
1728
1729 case SCTP_PARAM_HOST_NAME_ADDRESS:
1730 /* Tell the peer, we won't support this param. */
1731 return sctp_process_hn_param(asoc, param, chunk, err_chunk);
1732 case SCTP_PARAM_FWD_TSN_SUPPORT:
1733 if (sctp_prsctp_enable)
1734 break;
1735 /* Fall Through */
1736 default:
1737 SCTP_DEBUG_PRINTK("Unrecognized param: %d for chunk %d.\n",
1738 ntohs(param.p->type), cid);
1739 return sctp_process_unk_param(asoc, param, chunk, err_chunk);
1740
1741 break;
1742 }
1743 return retval;
1744}
1745
1746/* Verify the INIT packet before we process it. */
1747int sctp_verify_init(const struct sctp_association *asoc,
1748 sctp_cid_t cid,
1749 sctp_init_chunk_t *peer_init,
1750 struct sctp_chunk *chunk,
1751 struct sctp_chunk **errp)
1752{
1753 union sctp_params param;
1754 int has_cookie = 0;
1755
1756 /* Verify stream values are non-zero. */
1757 if ((0 == peer_init->init_hdr.num_outbound_streams) ||
1758 (0 == peer_init->init_hdr.num_inbound_streams)) {
1759
1760 sctp_process_inv_mandatory(asoc, chunk, errp);
1761 return 0;
1762 }
1763
1764 /* Check for missing mandatory parameters. */
1765 sctp_walk_params(param, peer_init, init_hdr.params) {
1766
1767 if (SCTP_PARAM_STATE_COOKIE == param.p->type)
1768 has_cookie = 1;
1769
1770 } /* for (loop through all parameters) */
1771
1772 /* There is a possibility that a parameter length was bad and
1773 * in that case we would have stoped walking the parameters.
1774 * The current param.p would point at the bad one.
1775 * Current consensus on the mailing list is to generate a PROTOCOL
1776 * VIOLATION error. We build the ERROR chunk here and let the normal
1777 * error handling code build and send the packet.
1778 */
1779 if (param.v < (void*)chunk->chunk_end - sizeof(sctp_paramhdr_t)) {
1780 sctp_process_inv_paramlength(asoc, param.p, chunk, errp);
1781 return 0;
1782 }
1783
1784 /* The only missing mandatory param possible today is
1785 * the state cookie for an INIT-ACK chunk.
1786 */
1787 if ((SCTP_CID_INIT_ACK == cid) && !has_cookie) {
1788 sctp_process_missing_param(asoc, SCTP_PARAM_STATE_COOKIE,
1789 chunk, errp);
1790 return 0;
1791 }
1792
1793 /* Find unrecognized parameters. */
1794
1795 sctp_walk_params(param, peer_init, init_hdr.params) {
1796
1797 if (!sctp_verify_param(asoc, param, cid, chunk, errp)) {
1798 if (SCTP_PARAM_HOST_NAME_ADDRESS == param.p->type)
1799 return 0;
1800 else
1801 return 1;
1802 }
1803
1804 } /* for (loop through all parameters) */
1805
1806 return 1;
1807}
1808
1809/* Unpack the parameters in an INIT packet into an association.
1810 * Returns 0 on failure, else success.
1811 * FIXME: This is an association method.
1812 */
1813int sctp_process_init(struct sctp_association *asoc, sctp_cid_t cid,
1814 const union sctp_addr *peer_addr,
1815 sctp_init_chunk_t *peer_init, int gfp)
1816{
1817 union sctp_params param;
1818 struct sctp_transport *transport;
1819 struct list_head *pos, *temp;
1820 char *cookie;
1821
1822 /* We must include the address that the INIT packet came from.
1823 * This is the only address that matters for an INIT packet.
1824 * When processing a COOKIE ECHO, we retrieve the from address
1825 * of the INIT from the cookie.
1826 */
1827
1828 /* This implementation defaults to making the first transport
1829 * added as the primary transport. The source address seems to
1830 * be a a better choice than any of the embedded addresses.
1831 */
1832 if (peer_addr)
1833 if(!sctp_assoc_add_peer(asoc, peer_addr, gfp))
1834 goto nomem;
1835
1836 /* Process the initialization parameters. */
1837
1838 sctp_walk_params(param, peer_init, init_hdr.params) {
1839
1840 if (!sctp_process_param(asoc, param, peer_addr, gfp))
1841 goto clean_up;
1842 }
1843
1844 /* The fixed INIT headers are always in network byte
1845 * order.
1846 */
1847 asoc->peer.i.init_tag =
1848 ntohl(peer_init->init_hdr.init_tag);
1849 asoc->peer.i.a_rwnd =
1850 ntohl(peer_init->init_hdr.a_rwnd);
1851 asoc->peer.i.num_outbound_streams =
1852 ntohs(peer_init->init_hdr.num_outbound_streams);
1853 asoc->peer.i.num_inbound_streams =
1854 ntohs(peer_init->init_hdr.num_inbound_streams);
1855 asoc->peer.i.initial_tsn =
1856 ntohl(peer_init->init_hdr.initial_tsn);
1857
1858 /* Apply the upper bounds for output streams based on peer's
1859 * number of inbound streams.
1860 */
1861 if (asoc->c.sinit_num_ostreams >
1862 ntohs(peer_init->init_hdr.num_inbound_streams)) {
1863 asoc->c.sinit_num_ostreams =
1864 ntohs(peer_init->init_hdr.num_inbound_streams);
1865 }
1866
1867 if (asoc->c.sinit_max_instreams >
1868 ntohs(peer_init->init_hdr.num_outbound_streams)) {
1869 asoc->c.sinit_max_instreams =
1870 ntohs(peer_init->init_hdr.num_outbound_streams);
1871 }
1872
1873 /* Copy Initiation tag from INIT to VT_peer in cookie. */
1874 asoc->c.peer_vtag = asoc->peer.i.init_tag;
1875
1876 /* Peer Rwnd : Current calculated value of the peer's rwnd. */
1877 asoc->peer.rwnd = asoc->peer.i.a_rwnd;
1878
1879 /* Copy cookie in case we need to resend COOKIE-ECHO. */
1880 cookie = asoc->peer.cookie;
1881 if (cookie) {
1882 asoc->peer.cookie = kmalloc(asoc->peer.cookie_len, gfp);
1883 if (!asoc->peer.cookie)
1884 goto clean_up;
1885 memcpy(asoc->peer.cookie, cookie, asoc->peer.cookie_len);
1886 }
1887
1888 /* RFC 2960 7.2.1 The initial value of ssthresh MAY be arbitrarily
1889 * high (for example, implementations MAY use the size of the receiver
1890 * advertised window).
1891 */
1892 list_for_each(pos, &asoc->peer.transport_addr_list) {
1893 transport = list_entry(pos, struct sctp_transport, transports);
1894 transport->ssthresh = asoc->peer.i.a_rwnd;
1895 }
1896
1897 /* Set up the TSN tracking pieces. */
1898 sctp_tsnmap_init(&asoc->peer.tsn_map, SCTP_TSN_MAP_SIZE,
1899 asoc->peer.i.initial_tsn);
1900
1901 /* RFC 2960 6.5 Stream Identifier and Stream Sequence Number
1902 *
1903 * The stream sequence number in all the streams shall start
1904 * from 0 when the association is established. Also, when the
1905 * stream sequence number reaches the value 65535 the next
1906 * stream sequence number shall be set to 0.
1907 */
1908
1909 /* Allocate storage for the negotiated streams if it is not a temporary * association.
1910 */
1911 if (!asoc->temp) {
1912 int assoc_id;
1913 int error;
1914
1915 asoc->ssnmap = sctp_ssnmap_new(asoc->c.sinit_max_instreams,
1916 asoc->c.sinit_num_ostreams, gfp);
1917 if (!asoc->ssnmap)
1918 goto clean_up;
1919
1920 retry:
1921 if (unlikely(!idr_pre_get(&sctp_assocs_id, gfp)))
1922 goto clean_up;
1923 spin_lock_bh(&sctp_assocs_id_lock);
1924 error = idr_get_new_above(&sctp_assocs_id, (void *)asoc, 1,
1925 &assoc_id);
1926 spin_unlock_bh(&sctp_assocs_id_lock);
1927 if (error == -EAGAIN)
1928 goto retry;
1929 else if (error)
1930 goto clean_up;
1931
1932 asoc->assoc_id = (sctp_assoc_t) assoc_id;
1933 }
1934
1935 /* ADDIP Section 4.1 ASCONF Chunk Procedures
1936 *
1937 * When an endpoint has an ASCONF signaled change to be sent to the
1938 * remote endpoint it should do the following:
1939 * ...
1940 * A2) A serial number should be assigned to the Chunk. The serial
1941 * number should be a monotonically increasing number. All serial
1942 * numbers are defined to be initialized at the start of the
1943 * association to the same value as the Initial TSN.
1944 */
1945 asoc->peer.addip_serial = asoc->peer.i.initial_tsn - 1;
1946 return 1;
1947
1948clean_up:
1949 /* Release the transport structures. */
1950 list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
1951 transport = list_entry(pos, struct sctp_transport, transports);
1952 list_del_init(pos);
1953 sctp_transport_free(transport);
1954 }
1955nomem:
1956 return 0;
1957}
1958
1959
1960/* Update asoc with the option described in param.
1961 *
1962 * RFC2960 3.3.2.1 Optional/Variable Length Parameters in INIT
1963 *
1964 * asoc is the association to update.
1965 * param is the variable length parameter to use for update.
1966 * cid tells us if this is an INIT, INIT ACK or COOKIE ECHO.
1967 * If the current packet is an INIT we want to minimize the amount of
1968 * work we do. In particular, we should not build transport
1969 * structures for the addresses.
1970 */
1971static int sctp_process_param(struct sctp_association *asoc,
1972 union sctp_params param,
1973 const union sctp_addr *peer_addr,
1974 int gfp)
1975{
1976 union sctp_addr addr;
1977 int i;
1978 __u16 sat;
1979 int retval = 1;
1980 sctp_scope_t scope;
1981 time_t stale;
1982 struct sctp_af *af;
1983
1984 /* We maintain all INIT parameters in network byte order all the
1985 * time. This allows us to not worry about whether the parameters
1986 * came from a fresh INIT, and INIT ACK, or were stored in a cookie.
1987 */
1988 switch (param.p->type) {
1989 case SCTP_PARAM_IPV6_ADDRESS:
1990 if (PF_INET6 != asoc->base.sk->sk_family)
1991 break;
1992 /* Fall through. */
1993 case SCTP_PARAM_IPV4_ADDRESS:
1994 af = sctp_get_af_specific(param_type2af(param.p->type));
1995 af->from_addr_param(&addr, param.addr, asoc->peer.port, 0);
1996 scope = sctp_scope(peer_addr);
1997 if (sctp_in_scope(&addr, scope))
1998 if (!sctp_assoc_add_peer(asoc, &addr, gfp))
1999 return 0;
2000 break;
2001
2002 case SCTP_PARAM_COOKIE_PRESERVATIVE:
2003 if (!sctp_cookie_preserve_enable)
2004 break;
2005
2006 stale = ntohl(param.life->lifespan_increment);
2007
2008 /* Suggested Cookie Life span increment's unit is msec,
2009 * (1/1000sec).
2010 */
2011 asoc->cookie_life.tv_sec += stale / 1000;
2012 asoc->cookie_life.tv_usec += (stale % 1000) * 1000;
2013 break;
2014
2015 case SCTP_PARAM_HOST_NAME_ADDRESS:
2016 SCTP_DEBUG_PRINTK("unimplemented SCTP_HOST_NAME_ADDRESS\n");
2017 break;
2018
2019 case SCTP_PARAM_SUPPORTED_ADDRESS_TYPES:
2020 /* Turn off the default values first so we'll know which
2021 * ones are really set by the peer.
2022 */
2023 asoc->peer.ipv4_address = 0;
2024 asoc->peer.ipv6_address = 0;
2025
2026 /* Cycle through address types; avoid divide by 0. */
2027 sat = ntohs(param.p->length) - sizeof(sctp_paramhdr_t);
2028 if (sat)
2029 sat /= sizeof(__u16);
2030
2031 for (i = 0; i < sat; ++i) {
2032 switch (param.sat->types[i]) {
2033 case SCTP_PARAM_IPV4_ADDRESS:
2034 asoc->peer.ipv4_address = 1;
2035 break;
2036
2037 case SCTP_PARAM_IPV6_ADDRESS:
2038 asoc->peer.ipv6_address = 1;
2039 break;
2040
2041 case SCTP_PARAM_HOST_NAME_ADDRESS:
2042 asoc->peer.hostname_address = 1;
2043 break;
2044
2045 default: /* Just ignore anything else. */
2046 break;
2047 };
2048 }
2049 break;
2050
2051 case SCTP_PARAM_STATE_COOKIE:
2052 asoc->peer.cookie_len =
2053 ntohs(param.p->length) - sizeof(sctp_paramhdr_t);
2054 asoc->peer.cookie = param.cookie->body;
2055 break;
2056
2057 case SCTP_PARAM_HEARTBEAT_INFO:
2058 /* Would be odd to receive, but it causes no problems. */
2059 break;
2060
2061 case SCTP_PARAM_UNRECOGNIZED_PARAMETERS:
2062 /* Rejected during verify stage. */
2063 break;
2064
2065 case SCTP_PARAM_ECN_CAPABLE:
2066 asoc->peer.ecn_capable = 1;
2067 break;
2068
2069 case SCTP_PARAM_ADAPTION_LAYER_IND:
2070 asoc->peer.adaption_ind = param.aind->adaption_ind;
2071 break;
2072
2073 case SCTP_PARAM_FWD_TSN_SUPPORT:
2074 if (sctp_prsctp_enable) {
2075 asoc->peer.prsctp_capable = 1;
2076 break;
2077 }
2078 /* Fall Through */
2079 default:
2080 /* Any unrecognized parameters should have been caught
2081 * and handled by sctp_verify_param() which should be
2082 * called prior to this routine. Simply log the error
2083 * here.
2084 */
2085 SCTP_DEBUG_PRINTK("Ignoring param: %d for association %p.\n",
2086 ntohs(param.p->type), asoc);
2087 break;
2088 };
2089
2090 return retval;
2091}
2092
2093/* Select a new verification tag. */
2094__u32 sctp_generate_tag(const struct sctp_endpoint *ep)
2095{
2096 /* I believe that this random number generator complies with RFC1750.
2097 * A tag of 0 is reserved for special cases (e.g. INIT).
2098 */
2099 __u32 x;
2100
2101 do {
2102 get_random_bytes(&x, sizeof(__u32));
2103 } while (x == 0);
2104
2105 return x;
2106}
2107
2108/* Select an initial TSN to send during startup. */
2109__u32 sctp_generate_tsn(const struct sctp_endpoint *ep)
2110{
2111 __u32 retval;
2112
2113 get_random_bytes(&retval, sizeof(__u32));
2114 return retval;
2115}
2116
2117/*
2118 * ADDIP 3.1.1 Address Configuration Change Chunk (ASCONF)
2119 * 0 1 2 3
2120 * 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
2121 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2122 * | Type = 0xC1 | Chunk Flags | Chunk Length |
2123 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2124 * | Serial Number |
2125 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2126 * | Address Parameter |
2127 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2128 * | ASCONF Parameter #1 |
2129 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2130 * \ \
2131 * / .... /
2132 * \ \
2133 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2134 * | ASCONF Parameter #N |
2135 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2136 *
2137 * Address Parameter and other parameter will not be wrapped in this function
2138 */
2139static struct sctp_chunk *sctp_make_asconf(struct sctp_association *asoc,
2140 union sctp_addr *addr,
2141 int vparam_len)
2142{
2143 sctp_addiphdr_t asconf;
2144 struct sctp_chunk *retval;
2145 int length = sizeof(asconf) + vparam_len;
2146 union sctp_addr_param addrparam;
2147 int addrlen;
2148 struct sctp_af *af = sctp_get_af_specific(addr->v4.sin_family);
2149
2150 addrlen = af->to_addr_param(addr, &addrparam);
2151 if (!addrlen)
2152 return NULL;
2153 length += addrlen;
2154
2155 /* Create the chunk. */
2156 retval = sctp_make_chunk(asoc, SCTP_CID_ASCONF, 0, length);
2157 if (!retval)
2158 return NULL;
2159
2160 asconf.serial = htonl(asoc->addip_serial++);
2161
2162 retval->subh.addip_hdr =
2163 sctp_addto_chunk(retval, sizeof(asconf), &asconf);
2164 retval->param_hdr.v =
2165 sctp_addto_chunk(retval, addrlen, &addrparam);
2166
2167 return retval;
2168}
2169
2170/* ADDIP
2171 * 3.2.1 Add IP Address
2172 * 0 1 2 3
2173 * 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
2174 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2175 * | Type = 0xC001 | Length = Variable |
2176 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2177 * | ASCONF-Request Correlation ID |
2178 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2179 * | Address Parameter |
2180 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2181 *
2182 * 3.2.2 Delete IP Address
2183 * 0 1 2 3
2184 * 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
2185 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2186 * | Type = 0xC002 | Length = Variable |
2187 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2188 * | ASCONF-Request Correlation ID |
2189 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2190 * | Address Parameter |
2191 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2192 *
2193 */
2194struct sctp_chunk *sctp_make_asconf_update_ip(struct sctp_association *asoc,
2195 union sctp_addr *laddr,
2196 struct sockaddr *addrs,
2197 int addrcnt,
2198 __u16 flags)
2199{
2200 sctp_addip_param_t param;
2201 struct sctp_chunk *retval;
2202 union sctp_addr_param addr_param;
2203 union sctp_addr *addr;
2204 void *addr_buf;
2205 struct sctp_af *af;
2206 int paramlen = sizeof(param);
2207 int addr_param_len = 0;
2208 int totallen = 0;
2209 int i;
2210
2211 /* Get total length of all the address parameters. */
2212 addr_buf = addrs;
2213 for (i = 0; i < addrcnt; i++) {
2214 addr = (union sctp_addr *)addr_buf;
2215 af = sctp_get_af_specific(addr->v4.sin_family);
2216 addr_param_len = af->to_addr_param(addr, &addr_param);
2217
2218 totallen += paramlen;
2219 totallen += addr_param_len;
2220
2221 addr_buf += af->sockaddr_len;
2222 }
2223
2224 /* Create an asconf chunk with the required length. */
2225 retval = sctp_make_asconf(asoc, laddr, totallen);
2226 if (!retval)
2227 return NULL;
2228
2229 /* Add the address parameters to the asconf chunk. */
2230 addr_buf = addrs;
2231 for (i = 0; i < addrcnt; i++) {
2232 addr = (union sctp_addr *)addr_buf;
2233 af = sctp_get_af_specific(addr->v4.sin_family);
2234 addr_param_len = af->to_addr_param(addr, &addr_param);
2235 param.param_hdr.type = flags;
2236 param.param_hdr.length = htons(paramlen + addr_param_len);
2237 param.crr_id = i;
2238
2239 sctp_addto_chunk(retval, paramlen, &param);
2240 sctp_addto_chunk(retval, addr_param_len, &addr_param);
2241
2242 addr_buf += af->sockaddr_len;
2243 }
2244 return retval;
2245}
2246
2247/* ADDIP
2248 * 3.2.4 Set Primary IP Address
2249 * 0 1 2 3
2250 * 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
2251 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2252 * | Type =0xC004 | Length = Variable |
2253 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2254 * | ASCONF-Request Correlation ID |
2255 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2256 * | Address Parameter |
2257 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2258 *
2259 * Create an ASCONF chunk with Set Primary IP address parameter.
2260 */
2261struct sctp_chunk *sctp_make_asconf_set_prim(struct sctp_association *asoc,
2262 union sctp_addr *addr)
2263{
2264 sctp_addip_param_t param;
2265 struct sctp_chunk *retval;
2266 int len = sizeof(param);
2267 union sctp_addr_param addrparam;
2268 int addrlen;
2269 struct sctp_af *af = sctp_get_af_specific(addr->v4.sin_family);
2270
2271 addrlen = af->to_addr_param(addr, &addrparam);
2272 if (!addrlen)
2273 return NULL;
2274 len += addrlen;
2275
2276 /* Create the chunk and make asconf header. */
2277 retval = sctp_make_asconf(asoc, addr, len);
2278 if (!retval)
2279 return NULL;
2280
2281 param.param_hdr.type = SCTP_PARAM_SET_PRIMARY;
2282 param.param_hdr.length = htons(len);
2283 param.crr_id = 0;
2284
2285 sctp_addto_chunk(retval, sizeof(param), &param);
2286 sctp_addto_chunk(retval, addrlen, &addrparam);
2287
2288 return retval;
2289}
2290
2291/* ADDIP 3.1.2 Address Configuration Acknowledgement Chunk (ASCONF-ACK)
2292 * 0 1 2 3
2293 * 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
2294 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2295 * | Type = 0x80 | Chunk Flags | Chunk Length |
2296 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2297 * | Serial Number |
2298 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2299 * | ASCONF Parameter Response#1 |
2300 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2301 * \ \
2302 * / .... /
2303 * \ \
2304 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2305 * | ASCONF Parameter Response#N |
2306 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2307 *
2308 * Create an ASCONF_ACK chunk with enough space for the parameter responses.
2309 */
2310static struct sctp_chunk *sctp_make_asconf_ack(const struct sctp_association *asoc,
2311 __u32 serial, int vparam_len)
2312{
2313 sctp_addiphdr_t asconf;
2314 struct sctp_chunk *retval;
2315 int length = sizeof(asconf) + vparam_len;
2316
2317 /* Create the chunk. */
2318 retval = sctp_make_chunk(asoc, SCTP_CID_ASCONF_ACK, 0, length);
2319 if (!retval)
2320 return NULL;
2321
2322 asconf.serial = htonl(serial);
2323
2324 retval->subh.addip_hdr =
2325 sctp_addto_chunk(retval, sizeof(asconf), &asconf);
2326
2327 return retval;
2328}
2329
2330/* Add response parameters to an ASCONF_ACK chunk. */
2331static void sctp_add_asconf_response(struct sctp_chunk *chunk, __u32 crr_id,
2332 __u16 err_code, sctp_addip_param_t *asconf_param)
2333{
2334 sctp_addip_param_t ack_param;
2335 sctp_errhdr_t err_param;
2336 int asconf_param_len = 0;
2337 int err_param_len = 0;
2338 __u16 response_type;
2339
2340 if (SCTP_ERROR_NO_ERROR == err_code) {
2341 response_type = SCTP_PARAM_SUCCESS_REPORT;
2342 } else {
2343 response_type = SCTP_PARAM_ERR_CAUSE;
2344 err_param_len = sizeof(err_param);
2345 if (asconf_param)
2346 asconf_param_len =
2347 ntohs(asconf_param->param_hdr.length);
2348 }
2349
2350 /* Add Success Indication or Error Cause Indication parameter. */
2351 ack_param.param_hdr.type = response_type;
2352 ack_param.param_hdr.length = htons(sizeof(ack_param) +
2353 err_param_len +
2354 asconf_param_len);
2355 ack_param.crr_id = crr_id;
2356 sctp_addto_chunk(chunk, sizeof(ack_param), &ack_param);
2357
2358 if (SCTP_ERROR_NO_ERROR == err_code)
2359 return;
2360
2361 /* Add Error Cause parameter. */
2362 err_param.cause = err_code;
2363 err_param.length = htons(err_param_len + asconf_param_len);
2364 sctp_addto_chunk(chunk, err_param_len, &err_param);
2365
2366 /* Add the failed TLV copied from ASCONF chunk. */
2367 if (asconf_param)
2368 sctp_addto_chunk(chunk, asconf_param_len, asconf_param);
2369}
2370
2371/* Process a asconf parameter. */
2372static __u16 sctp_process_asconf_param(struct sctp_association *asoc,
2373 struct sctp_chunk *asconf,
2374 sctp_addip_param_t *asconf_param)
2375{
2376 struct sctp_transport *peer;
2377 struct sctp_af *af;
2378 union sctp_addr addr;
2379 struct list_head *pos;
2380 union sctp_addr_param *addr_param;
2381
2382 addr_param = (union sctp_addr_param *)
2383 ((void *)asconf_param + sizeof(sctp_addip_param_t));
2384
2385 af = sctp_get_af_specific(param_type2af(addr_param->v4.param_hdr.type));
2386 if (unlikely(!af))
2387 return SCTP_ERROR_INV_PARAM;
2388
2389 af->from_addr_param(&addr, addr_param, asoc->peer.port, 0);
2390 switch (asconf_param->param_hdr.type) {
2391 case SCTP_PARAM_ADD_IP:
2392 /* ADDIP 4.3 D9) If an endpoint receives an ADD IP address
2393 * request and does not have the local resources to add this
2394 * new address to the association, it MUST return an Error
2395 * Cause TLV set to the new error code 'Operation Refused
2396 * Due to Resource Shortage'.
2397 */
2398
2399 peer = sctp_assoc_add_peer(asoc, &addr, GFP_ATOMIC);
2400 if (!peer)
2401 return SCTP_ERROR_RSRC_LOW;
2402
2403 /* Start the heartbeat timer. */
2404 if (!mod_timer(&peer->hb_timer, sctp_transport_timeout(peer)))
2405 sctp_transport_hold(peer);
2406 break;
2407 case SCTP_PARAM_DEL_IP:
2408 /* ADDIP 4.3 D7) If a request is received to delete the
2409 * last remaining IP address of a peer endpoint, the receiver
2410 * MUST send an Error Cause TLV with the error cause set to the
2411 * new error code 'Request to Delete Last Remaining IP Address'.
2412 */
2413 pos = asoc->peer.transport_addr_list.next;
2414 if (pos->next == &asoc->peer.transport_addr_list)
2415 return SCTP_ERROR_DEL_LAST_IP;
2416
2417 /* ADDIP 4.3 D8) If a request is received to delete an IP
2418 * address which is also the source address of the IP packet
2419 * which contained the ASCONF chunk, the receiver MUST reject
2420 * this request. To reject the request the receiver MUST send
2421 * an Error Cause TLV set to the new error code 'Request to
2422 * Delete Source IP Address'
2423 */
2424 if (sctp_cmp_addr_exact(sctp_source(asconf), &addr))
2425 return SCTP_ERROR_DEL_SRC_IP;
2426
2427 sctp_assoc_del_peer(asoc, &addr);
2428 break;
2429 case SCTP_PARAM_SET_PRIMARY:
2430 peer = sctp_assoc_lookup_paddr(asoc, &addr);
2431 if (!peer)
2432 return SCTP_ERROR_INV_PARAM;
2433
2434 sctp_assoc_set_primary(asoc, peer);
2435 break;
2436 default:
2437 return SCTP_ERROR_INV_PARAM;
2438 break;
2439 }
2440
2441 return SCTP_ERROR_NO_ERROR;
2442}
2443
2444/* Process an incoming ASCONF chunk with the next expected serial no. and
2445 * return an ASCONF_ACK chunk to be sent in response.
2446 */
2447struct sctp_chunk *sctp_process_asconf(struct sctp_association *asoc,
2448 struct sctp_chunk *asconf)
2449{
2450 sctp_addiphdr_t *hdr;
2451 union sctp_addr_param *addr_param;
2452 sctp_addip_param_t *asconf_param;
2453 struct sctp_chunk *asconf_ack;
2454
2455 __u16 err_code;
2456 int length = 0;
2457 int chunk_len = asconf->skb->len;
2458 __u32 serial;
2459 int all_param_pass = 1;
2460
2461 hdr = (sctp_addiphdr_t *)asconf->skb->data;
2462 serial = ntohl(hdr->serial);
2463
2464 /* Skip the addiphdr and store a pointer to address parameter. */
2465 length = sizeof(sctp_addiphdr_t);
2466 addr_param = (union sctp_addr_param *)(asconf->skb->data + length);
2467 chunk_len -= length;
2468
2469 /* Skip the address parameter and store a pointer to the first
2470 * asconf paramter.
2471 */
2472 length = ntohs(addr_param->v4.param_hdr.length);
2473 asconf_param = (sctp_addip_param_t *)((void *)addr_param + length);
2474 chunk_len -= length;
2475
2476 /* create an ASCONF_ACK chunk.
2477 * Based on the definitions of parameters, we know that the size of
2478 * ASCONF_ACK parameters are less than or equal to the twice of ASCONF
2479 * paramters.
2480 */
2481 asconf_ack = sctp_make_asconf_ack(asoc, serial, chunk_len * 2);
2482 if (!asconf_ack)
2483 goto done;
2484
2485 /* Process the TLVs contained within the ASCONF chunk. */
2486 while (chunk_len > 0) {
2487 err_code = sctp_process_asconf_param(asoc, asconf,
2488 asconf_param);
2489 /* ADDIP 4.1 A7)
2490 * If an error response is received for a TLV parameter,
2491 * all TLVs with no response before the failed TLV are
2492 * considered successful if not reported. All TLVs after
2493 * the failed response are considered unsuccessful unless
2494 * a specific success indication is present for the parameter.
2495 */
2496 if (SCTP_ERROR_NO_ERROR != err_code)
2497 all_param_pass = 0;
2498
2499 if (!all_param_pass)
2500 sctp_add_asconf_response(asconf_ack,
2501 asconf_param->crr_id, err_code,
2502 asconf_param);
2503
2504 /* ADDIP 4.3 D11) When an endpoint receiving an ASCONF to add
2505 * an IP address sends an 'Out of Resource' in its response, it
2506 * MUST also fail any subsequent add or delete requests bundled
2507 * in the ASCONF.
2508 */
2509 if (SCTP_ERROR_RSRC_LOW == err_code)
2510 goto done;
2511
2512 /* Move to the next ASCONF param. */
2513 length = ntohs(asconf_param->param_hdr.length);
2514 asconf_param = (sctp_addip_param_t *)((void *)asconf_param +
2515 length);
2516 chunk_len -= length;
2517 }
2518
2519done:
2520 asoc->peer.addip_serial++;
2521
2522 /* If we are sending a new ASCONF_ACK hold a reference to it in assoc
2523 * after freeing the reference to old asconf ack if any.
2524 */
2525 if (asconf_ack) {
2526 if (asoc->addip_last_asconf_ack)
2527 sctp_chunk_free(asoc->addip_last_asconf_ack);
2528
2529 sctp_chunk_hold(asconf_ack);
2530 asoc->addip_last_asconf_ack = asconf_ack;
2531 }
2532
2533 return asconf_ack;
2534}
2535
2536/* Process a asconf parameter that is successfully acked. */
2537static int sctp_asconf_param_success(struct sctp_association *asoc,
2538 sctp_addip_param_t *asconf_param)
2539{
2540 struct sctp_af *af;
2541 union sctp_addr addr;
2542 struct sctp_bind_addr *bp = &asoc->base.bind_addr;
2543 union sctp_addr_param *addr_param;
2544 struct list_head *pos;
2545 struct sctp_transport *transport;
2546 int retval = 0;
2547
2548 addr_param = (union sctp_addr_param *)
2549 ((void *)asconf_param + sizeof(sctp_addip_param_t));
2550
2551 /* We have checked the packet before, so we do not check again. */
2552 af = sctp_get_af_specific(param_type2af(addr_param->v4.param_hdr.type));
2553 af->from_addr_param(&addr, addr_param, bp->port, 0);
2554
2555 switch (asconf_param->param_hdr.type) {
2556 case SCTP_PARAM_ADD_IP:
2557 sctp_local_bh_disable();
2558 sctp_write_lock(&asoc->base.addr_lock);
2559 retval = sctp_add_bind_addr(bp, &addr, GFP_ATOMIC);
2560 sctp_write_unlock(&asoc->base.addr_lock);
2561 sctp_local_bh_enable();
2562 break;
2563 case SCTP_PARAM_DEL_IP:
2564 sctp_local_bh_disable();
2565 sctp_write_lock(&asoc->base.addr_lock);
2566 retval = sctp_del_bind_addr(bp, &addr);
2567 sctp_write_unlock(&asoc->base.addr_lock);
2568 sctp_local_bh_enable();
2569 list_for_each(pos, &asoc->peer.transport_addr_list) {
2570 transport = list_entry(pos, struct sctp_transport,
2571 transports);
2572 sctp_transport_route(transport, NULL,
2573 sctp_sk(asoc->base.sk));
2574 }
2575 break;
2576 default:
2577 break;
2578 }
2579
2580 return retval;
2581}
2582
2583/* Get the corresponding ASCONF response error code from the ASCONF_ACK chunk
2584 * for the given asconf parameter. If there is no response for this parameter,
2585 * return the error code based on the third argument 'no_err'.
2586 * ADDIP 4.1
2587 * A7) If an error response is received for a TLV parameter, all TLVs with no
2588 * response before the failed TLV are considered successful if not reported.
2589 * All TLVs after the failed response are considered unsuccessful unless a
2590 * specific success indication is present for the parameter.
2591 */
2592static __u16 sctp_get_asconf_response(struct sctp_chunk *asconf_ack,
2593 sctp_addip_param_t *asconf_param,
2594 int no_err)
2595{
2596 sctp_addip_param_t *asconf_ack_param;
2597 sctp_errhdr_t *err_param;
2598 int length;
2599 int asconf_ack_len = asconf_ack->skb->len;
2600 __u16 err_code;
2601
2602 if (no_err)
2603 err_code = SCTP_ERROR_NO_ERROR;
2604 else
2605 err_code = SCTP_ERROR_REQ_REFUSED;
2606
2607 /* Skip the addiphdr from the asconf_ack chunk and store a pointer to
2608 * the first asconf_ack parameter.
2609 */
2610 length = sizeof(sctp_addiphdr_t);
2611 asconf_ack_param = (sctp_addip_param_t *)(asconf_ack->skb->data +
2612 length);
2613 asconf_ack_len -= length;
2614
2615 while (asconf_ack_len > 0) {
2616 if (asconf_ack_param->crr_id == asconf_param->crr_id) {
2617 switch(asconf_ack_param->param_hdr.type) {
2618 case SCTP_PARAM_SUCCESS_REPORT:
2619 return SCTP_ERROR_NO_ERROR;
2620 case SCTP_PARAM_ERR_CAUSE:
2621 length = sizeof(sctp_addip_param_t);
2622 err_param = (sctp_errhdr_t *)
2623 ((void *)asconf_ack_param + length);
2624 asconf_ack_len -= length;
2625 if (asconf_ack_len > 0)
2626 return err_param->cause;
2627 else
2628 return SCTP_ERROR_INV_PARAM;
2629 break;
2630 default:
2631 return SCTP_ERROR_INV_PARAM;
2632 }
2633 }
2634
2635 length = ntohs(asconf_ack_param->param_hdr.length);
2636 asconf_ack_param = (sctp_addip_param_t *)
2637 ((void *)asconf_ack_param + length);
2638 asconf_ack_len -= length;
2639 }
2640
2641 return err_code;
2642}
2643
2644/* Process an incoming ASCONF_ACK chunk against the cached last ASCONF chunk. */
2645int sctp_process_asconf_ack(struct sctp_association *asoc,
2646 struct sctp_chunk *asconf_ack)
2647{
2648 struct sctp_chunk *asconf = asoc->addip_last_asconf;
2649 union sctp_addr_param *addr_param;
2650 sctp_addip_param_t *asconf_param;
2651 int length = 0;
2652 int asconf_len = asconf->skb->len;
2653 int all_param_pass = 0;
2654 int no_err = 1;
2655 int retval = 0;
2656 __u16 err_code = SCTP_ERROR_NO_ERROR;
2657
2658 /* Skip the chunkhdr and addiphdr from the last asconf sent and store
2659 * a pointer to address parameter.
2660 */
2661 length = sizeof(sctp_addip_chunk_t);
2662 addr_param = (union sctp_addr_param *)(asconf->skb->data + length);
2663 asconf_len -= length;
2664
2665 /* Skip the address parameter in the last asconf sent and store a
2666 * pointer to the first asconf paramter.
2667 */
2668 length = ntohs(addr_param->v4.param_hdr.length);
2669 asconf_param = (sctp_addip_param_t *)((void *)addr_param + length);
2670 asconf_len -= length;
2671
2672 /* ADDIP 4.1
2673 * A8) If there is no response(s) to specific TLV parameter(s), and no
2674 * failures are indicated, then all request(s) are considered
2675 * successful.
2676 */
2677 if (asconf_ack->skb->len == sizeof(sctp_addiphdr_t))
2678 all_param_pass = 1;
2679
2680 /* Process the TLVs contained in the last sent ASCONF chunk. */
2681 while (asconf_len > 0) {
2682 if (all_param_pass)
2683 err_code = SCTP_ERROR_NO_ERROR;
2684 else {
2685 err_code = sctp_get_asconf_response(asconf_ack,
2686 asconf_param,
2687 no_err);
2688 if (no_err && (SCTP_ERROR_NO_ERROR != err_code))
2689 no_err = 0;
2690 }
2691
2692 switch (err_code) {
2693 case SCTP_ERROR_NO_ERROR:
2694 retval = sctp_asconf_param_success(asoc, asconf_param);
2695 break;
2696
2697 case SCTP_ERROR_RSRC_LOW:
2698 retval = 1;
2699 break;
2700
2701 case SCTP_ERROR_INV_PARAM:
2702 /* Disable sending this type of asconf parameter in
2703 * future.
2704 */
2705 asoc->peer.addip_disabled_mask |=
2706 asconf_param->param_hdr.type;
2707 break;
2708
2709 case SCTP_ERROR_REQ_REFUSED:
2710 case SCTP_ERROR_DEL_LAST_IP:
2711 case SCTP_ERROR_DEL_SRC_IP:
2712 default:
2713 break;
2714 }
2715
2716 /* Skip the processed asconf parameter and move to the next
2717 * one.
2718 */
2719 length = ntohs(asconf_param->param_hdr.length);
2720 asconf_param = (sctp_addip_param_t *)((void *)asconf_param +
2721 length);
2722 asconf_len -= length;
2723 }
2724
2725 /* Free the cached last sent asconf chunk. */
2726 sctp_chunk_free(asconf);
2727 asoc->addip_last_asconf = NULL;
2728
2729 /* Send the next asconf chunk from the addip chunk queue. */
2730 asconf = (struct sctp_chunk *)__skb_dequeue(&asoc->addip_chunks);
2731 if (asconf) {
2732 /* Hold the chunk until an ASCONF_ACK is received. */
2733 sctp_chunk_hold(asconf);
2734 if (sctp_primitive_ASCONF(asoc, asconf))
2735 sctp_chunk_free(asconf);
2736 else
2737 asoc->addip_last_asconf = asconf;
2738 }
2739
2740 return retval;
2741}
2742
2743/* Make a FWD TSN chunk. */
2744struct sctp_chunk *sctp_make_fwdtsn(const struct sctp_association *asoc,
2745 __u32 new_cum_tsn, size_t nstreams,
2746 struct sctp_fwdtsn_skip *skiplist)
2747{
2748 struct sctp_chunk *retval = NULL;
2749 struct sctp_fwdtsn_chunk *ftsn_chunk;
2750 struct sctp_fwdtsn_hdr ftsn_hdr;
2751 struct sctp_fwdtsn_skip skip;
2752 size_t hint;
2753 int i;
2754
2755 hint = (nstreams + 1) * sizeof(__u32);
2756
Linus Torvalds1da177e2005-04-16 15:20:36 -07002757 retval = sctp_make_chunk(asoc, SCTP_CID_FWD_TSN, 0, hint);
2758
2759 if (!retval)
2760 return NULL;
2761
2762 ftsn_chunk = (struct sctp_fwdtsn_chunk *)retval->subh.fwdtsn_hdr;
2763
2764 ftsn_hdr.new_cum_tsn = htonl(new_cum_tsn);
2765 retval->subh.fwdtsn_hdr =
2766 sctp_addto_chunk(retval, sizeof(ftsn_hdr), &ftsn_hdr);
2767
2768 for (i = 0; i < nstreams; i++) {
2769 skip.stream = skiplist[i].stream;
2770 skip.ssn = skiplist[i].ssn;
2771 sctp_addto_chunk(retval, sizeof(skip), &skip);
2772 }
2773
2774 return retval;
2775}