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sctp: Fix kernel panic while process protocol violation parameter
[linux-2.6.git] / net / sctp / sm_make_chunk.c
blobd68869f966c3b3b99fb70f8361cae85452f98632
1 /* SCTP kernel implementation
2 * (C) Copyright IBM Corp. 2001, 2004
3 * Copyright (c) 1999-2000 Cisco, Inc.
4 * Copyright (c) 1999-2001 Motorola, Inc.
5 * Copyright (c) 2001-2002 Intel Corp.
6 *
7 * This file is part of the SCTP kernel implementation
8 *
9 * These functions work with the state functions in sctp_sm_statefuns.c
10 * to implement the state operations. These functions implement the
11 * steps which require modifying existing data structures.
12 *
13 * This SCTP implementation is free software;
14 * you can redistribute it and/or modify it under the terms of
15 * the GNU General Public License as published by
16 * the Free Software Foundation; either version 2, or (at your option)
17 * any later version.
18 *
19 * This SCTP implementation is distributed in the hope that it
20 * will be useful, but WITHOUT ANY WARRANTY; without even the implied
21 * ************************
22 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
23 * See the GNU General Public License for more details.
24 *
25 * You should have received a copy of the GNU General Public License
26 * along with GNU CC; see the file COPYING. If not, write to
27 * the Free Software Foundation, 59 Temple Place - Suite 330,
28 * Boston, MA 02111-1307, USA.
29 *
30 * Please send any bug reports or fixes you make to the
31 * email address(es):
32 * lksctp developers <lksctp-developers@lists.sourceforge.net>
33 *
34 * Or submit a bug report through the following website:
35 * http://www.sf.net/projects/lksctp
36 *
37 * Written or modified by:
38 * La Monte H.P. Yarroll <piggy@acm.org>
39 * Karl Knutson <karl@athena.chicago.il.us>
40 * C. Robin <chris@hundredacre.ac.uk>
41 * Jon Grimm <jgrimm@us.ibm.com>
42 * Xingang Guo <xingang.guo@intel.com>
43 * Dajiang Zhang <dajiang.zhang@nokia.com>
44 * Sridhar Samudrala <sri@us.ibm.com>
45 * Daisy Chang <daisyc@us.ibm.com>
46 * Ardelle Fan <ardelle.fan@intel.com>
47 * Kevin Gao <kevin.gao@intel.com>
48 *
49 * Any bugs reported given to us we will try to fix... any fixes shared will
50 * be incorporated into the next SCTP release.
51 */
52
53 #include <linux/types.h>
54 #include <linux/kernel.h>
55 #include <linux/ip.h>
56 #include <linux/ipv6.h>
57 #include <linux/net.h>
58 #include <linux/inet.h>
59 #include <linux/scatterlist.h>
60 #include <linux/crypto.h>
61 #include <net/sock.h>
62
63 #include <linux/skbuff.h>
64 #include <linux/random.h> /* for get_random_bytes */
65 #include <net/sctp/sctp.h>
66 #include <net/sctp/sm.h>
67
68 SCTP_STATIC
69 struct sctp_chunk *sctp_make_chunk(const struct sctp_association *asoc,
70 __u8 type, __u8 flags, int paylen);
71 static sctp_cookie_param_t *sctp_pack_cookie(const struct sctp_endpoint *ep,
72 const struct sctp_association *asoc,
73 const struct sctp_chunk *init_chunk,
74 int *cookie_len,
75 const __u8 *raw_addrs, int addrs_len);
76 static int sctp_process_param(struct sctp_association *asoc,
77 union sctp_params param,
78 const union sctp_addr *peer_addr,
79 gfp_t gfp);
80 static void *sctp_addto_param(struct sctp_chunk *chunk, int len,
81 const void *data);
82
83 /* What was the inbound interface for this chunk? */
84 int sctp_chunk_iif(const struct sctp_chunk *chunk)
85 {
86 struct sctp_af *af;
87 int iif = 0;
88
89 af = sctp_get_af_specific(ipver2af(ip_hdr(chunk->skb)->version));
90 if (af)
91 iif = af->skb_iif(chunk->skb);
92
93 return iif;
94 }
95
96 /* RFC 2960 3.3.2 Initiation (INIT) (1)
97 *
98 * Note 2: The ECN capable field is reserved for future use of
99 * Explicit Congestion Notification.
100 */
101 static const struct sctp_paramhdr ecap_param = {
102 SCTP_PARAM_ECN_CAPABLE,
103 __constant_htons(sizeof(struct sctp_paramhdr)),
104 };
105 static 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 */
114 void sctp_init_cause(struct sctp_chunk *chunk, __be16 cause_code,
115 size_t paylen)
116 {
117 sctp_errhdr_t err;
118 __u16 len;
119
120 /* Cause code constants are now defined in network order. */
121 err.cause = cause_code;
122 len = sizeof(sctp_errhdr_t) + paylen;
123 err.length = htons(len);
124 chunk->subh.err_hdr = sctp_addto_chunk(chunk, sizeof(sctp_errhdr_t), &err);
125 }
126
127 /* 3.3.2 Initiation (INIT) (1)
128 *
129 * This chunk is used to initiate a SCTP association between two
130 * endpoints. The format of the INIT chunk is shown below:
131 *
132 * 0 1 2 3
133 * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
134 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
135 * | Type = 1 | Chunk Flags | Chunk Length |
136 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
137 * | Initiate Tag |
138 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
139 * | Advertised Receiver Window Credit (a_rwnd) |
140 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
141 * | Number of Outbound Streams | Number of Inbound Streams |
142 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
143 * | Initial TSN |
144 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
145 * \ \
146 * / Optional/Variable-Length Parameters /
147 * \ \
148 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
149 *
150 *
151 * The INIT chunk contains the following parameters. Unless otherwise
152 * noted, each parameter MUST only be included once in the INIT chunk.
153 *
154 * Fixed Parameters Status
155 * ----------------------------------------------
156 * Initiate Tag Mandatory
157 * Advertised Receiver Window Credit Mandatory
158 * Number of Outbound Streams Mandatory
159 * Number of Inbound Streams Mandatory
160 * Initial TSN Mandatory
161 *
162 * Variable Parameters Status Type Value
163 * -------------------------------------------------------------
164 * IPv4 Address (Note 1) Optional 5
165 * IPv6 Address (Note 1) Optional 6
166 * Cookie Preservative Optional 9
167 * Reserved for ECN Capable (Note 2) Optional 32768 (0x8000)
168 * Host Name Address (Note 3) Optional 11
169 * Supported Address Types (Note 4) Optional 12
170 */
171 struct sctp_chunk *sctp_make_init(const struct sctp_association *asoc,
172 const struct sctp_bind_addr *bp,
173 gfp_t gfp, int vparam_len)
174 {
175 sctp_inithdr_t init;
176 union sctp_params addrs;
177 size_t chunksize;
178 struct sctp_chunk *retval = NULL;
179 int num_types, addrs_len = 0;
180 struct sctp_sock *sp;
181 sctp_supported_addrs_param_t sat;
182 __be16 types[2];
183 sctp_adaptation_ind_param_t aiparam;
184 sctp_supported_ext_param_t ext_param;
185 int num_ext = 0;
186 __u8 extensions[3];
187 sctp_paramhdr_t *auth_chunks = NULL,
188 *auth_hmacs = NULL;
189
190 /* RFC 2960 3.3.2 Initiation (INIT) (1)
191 *
192 * Note 1: The INIT chunks can contain multiple addresses that
193 * can be IPv4 and/or IPv6 in any combination.
194 */
195 retval = NULL;
196
197 /* Convert the provided bind address list to raw format. */
198 addrs = sctp_bind_addrs_to_raw(bp, &addrs_len, gfp);
199
200 init.init_tag = htonl(asoc->c.my_vtag);
201 init.a_rwnd = htonl(asoc->rwnd);
202 init.num_outbound_streams = htons(asoc->c.sinit_num_ostreams);
203 init.num_inbound_streams = htons(asoc->c.sinit_max_instreams);
204 init.initial_tsn = htonl(asoc->c.initial_tsn);
205
206 /* How many address types are needed? */
207 sp = sctp_sk(asoc->base.sk);
208 num_types = sp->pf->supported_addrs(sp, types);
209
210 chunksize = sizeof(init) + addrs_len + SCTP_SAT_LEN(num_types);
211 chunksize += sizeof(ecap_param);
212
213 if (sctp_prsctp_enable)
214 chunksize += sizeof(prsctp_param);
215
216 /* ADDIP: Section 4.2.7:
217 * An implementation supporting this extension [ADDIP] MUST list
218 * the ASCONF,the ASCONF-ACK, and the AUTH chunks in its INIT and
219 * INIT-ACK parameters.
220 */
221 if (sctp_addip_enable) {
222 extensions[num_ext] = SCTP_CID_ASCONF;
223 extensions[num_ext+1] = SCTP_CID_ASCONF_ACK;
224 num_ext += 2;
225 }
226
227 chunksize += sizeof(aiparam);
228 chunksize += vparam_len;
229
230 /* Account for AUTH related parameters */
231 if (sctp_auth_enable) {
232 /* Add random parameter length*/
233 chunksize += sizeof(asoc->c.auth_random);
234
235 /* Add HMACS parameter length if any were defined */
236 auth_hmacs = (sctp_paramhdr_t *)asoc->c.auth_hmacs;
237 if (auth_hmacs->length)
238 chunksize += ntohs(auth_hmacs->length);
239 else
240 auth_hmacs = NULL;
241
242 /* Add CHUNKS parameter length */
243 auth_chunks = (sctp_paramhdr_t *)asoc->c.auth_chunks;
244 if (auth_chunks->length)
245 chunksize += ntohs(auth_chunks->length);
246 else
247 auth_chunks = NULL;
248
249 extensions[num_ext] = SCTP_CID_AUTH;
250 num_ext += 1;
251 }
252
253 /* If we have any extensions to report, account for that */
254 if (num_ext)
255 chunksize += sizeof(sctp_supported_ext_param_t) + num_ext;
256
257 /* RFC 2960 3.3.2 Initiation (INIT) (1)
258 *
259 * Note 3: An INIT chunk MUST NOT contain more than one Host
260 * Name address parameter. Moreover, the sender of the INIT
261 * MUST NOT combine any other address types with the Host Name
262 * address in the INIT. The receiver of INIT MUST ignore any
263 * other address types if the Host Name address parameter is
264 * present in the received INIT chunk.
265 *
266 * PLEASE DO NOT FIXME [This version does not support Host Name.]
267 */
268
269 retval = sctp_make_chunk(asoc, SCTP_CID_INIT, 0, chunksize);
270 if (!retval)
271 goto nodata;
272
273 retval->subh.init_hdr =
274 sctp_addto_chunk(retval, sizeof(init), &init);
275 retval->param_hdr.v =
276 sctp_addto_chunk(retval, addrs_len, addrs.v);
277
278 /* RFC 2960 3.3.2 Initiation (INIT) (1)
279 *
280 * Note 4: This parameter, when present, specifies all the
281 * address types the sending endpoint can support. The absence
282 * of this parameter indicates that the sending endpoint can
283 * support any address type.
284 */
285 sat.param_hdr.type = SCTP_PARAM_SUPPORTED_ADDRESS_TYPES;
286 sat.param_hdr.length = htons(SCTP_SAT_LEN(num_types));
287 sctp_addto_chunk(retval, sizeof(sat), &sat);
288 sctp_addto_chunk(retval, num_types * sizeof(__u16), &types);
289
290 sctp_addto_chunk(retval, sizeof(ecap_param), &ecap_param);
291
292 /* Add the supported extensions parameter. Be nice and add this
293 * fist before addiding the parameters for the extensions themselves
294 */
295 if (num_ext) {
296 ext_param.param_hdr.type = SCTP_PARAM_SUPPORTED_EXT;
297 ext_param.param_hdr.length =
298 htons(sizeof(sctp_supported_ext_param_t) + num_ext);
299 sctp_addto_chunk(retval, sizeof(sctp_supported_ext_param_t),
300 &ext_param);
301 sctp_addto_param(retval, num_ext, extensions);
302 }
303
304 if (sctp_prsctp_enable)
305 sctp_addto_chunk(retval, sizeof(prsctp_param), &prsctp_param);
306
307 aiparam.param_hdr.type = SCTP_PARAM_ADAPTATION_LAYER_IND;
308 aiparam.param_hdr.length = htons(sizeof(aiparam));
309 aiparam.adaptation_ind = htonl(sp->adaptation_ind);
310 sctp_addto_chunk(retval, sizeof(aiparam), &aiparam);
311
312 /* Add SCTP-AUTH chunks to the parameter list */
313 if (sctp_auth_enable) {
314 sctp_addto_chunk(retval, sizeof(asoc->c.auth_random),
315 asoc->c.auth_random);
316 if (auth_hmacs)
317 sctp_addto_chunk(retval, ntohs(auth_hmacs->length),
318 auth_hmacs);
319 if (auth_chunks)
320 sctp_addto_chunk(retval, ntohs(auth_chunks->length),
321 auth_chunks);
322 }
323 nodata:
324 kfree(addrs.v);
325 return retval;
326 }
327
328 struct sctp_chunk *sctp_make_init_ack(const struct sctp_association *asoc,
329 const struct sctp_chunk *chunk,
330 gfp_t gfp, int unkparam_len)
331 {
332 sctp_inithdr_t initack;
333 struct sctp_chunk *retval;
334 union sctp_params addrs;
335 int addrs_len;
336 sctp_cookie_param_t *cookie;
337 int cookie_len;
338 size_t chunksize;
339 sctp_adaptation_ind_param_t aiparam;
340 sctp_supported_ext_param_t ext_param;
341 int num_ext = 0;
342 __u8 extensions[3];
343 sctp_paramhdr_t *auth_chunks = NULL,
344 *auth_hmacs = NULL,
345 *auth_random = NULL;
346
347 retval = NULL;
348
349 /* Note: there may be no addresses to embed. */
350 addrs = sctp_bind_addrs_to_raw(&asoc->base.bind_addr, &addrs_len, gfp);
351
352 initack.init_tag = htonl(asoc->c.my_vtag);
353 initack.a_rwnd = htonl(asoc->rwnd);
354 initack.num_outbound_streams = htons(asoc->c.sinit_num_ostreams);
355 initack.num_inbound_streams = htons(asoc->c.sinit_max_instreams);
356 initack.initial_tsn = htonl(asoc->c.initial_tsn);
357
358 /* FIXME: We really ought to build the cookie right
359 * into the packet instead of allocating more fresh memory.
360 */
361 cookie = sctp_pack_cookie(asoc->ep, asoc, chunk, &cookie_len,
362 addrs.v, addrs_len);
363 if (!cookie)
364 goto nomem_cookie;
365
366 /* Calculate the total size of allocation, include the reserved
367 * space for reporting unknown parameters if it is specified.
368 */
369 chunksize = sizeof(initack) + addrs_len + cookie_len + unkparam_len;
370
371 /* Tell peer that we'll do ECN only if peer advertised such cap. */
372 if (asoc->peer.ecn_capable)
373 chunksize += sizeof(ecap_param);
374
375 if (sctp_prsctp_enable)
376 chunksize += sizeof(prsctp_param);
377
378 if (sctp_addip_enable) {
379 extensions[num_ext] = SCTP_CID_ASCONF;
380 extensions[num_ext+1] = SCTP_CID_ASCONF_ACK;
381 num_ext += 2;
382 }
383
384 chunksize += sizeof(aiparam);
385
386 if (asoc->peer.auth_capable) {
387 auth_random = (sctp_paramhdr_t *)asoc->c.auth_random;
388 chunksize += ntohs(auth_random->length);
389
390 auth_hmacs = (sctp_paramhdr_t *)asoc->c.auth_hmacs;
391 if (auth_hmacs->length)
392 chunksize += ntohs(auth_hmacs->length);
393 else
394 auth_hmacs = NULL;
395
396 auth_chunks = (sctp_paramhdr_t *)asoc->c.auth_chunks;
397 if (auth_chunks->length)
398 chunksize += ntohs(auth_chunks->length);
399 else
400 auth_chunks = NULL;
401
402 extensions[num_ext] = SCTP_CID_AUTH;
403 num_ext += 1;
404 }
405
406 if (num_ext)
407 chunksize += sizeof(sctp_supported_ext_param_t) + num_ext;
408
409 /* Now allocate and fill out the chunk. */
410 retval = sctp_make_chunk(asoc, SCTP_CID_INIT_ACK, 0, chunksize);
411 if (!retval)
412 goto nomem_chunk;
413
414 /* Per the advice in RFC 2960 6.4, send this reply to
415 * the source of the INIT packet.
416 */
417 retval->transport = chunk->transport;
418 retval->subh.init_hdr =
419 sctp_addto_chunk(retval, sizeof(initack), &initack);
420 retval->param_hdr.v = sctp_addto_chunk(retval, addrs_len, addrs.v);
421 sctp_addto_chunk(retval, cookie_len, cookie);
422 if (asoc->peer.ecn_capable)
423 sctp_addto_chunk(retval, sizeof(ecap_param), &ecap_param);
424 if (num_ext) {
425 ext_param.param_hdr.type = SCTP_PARAM_SUPPORTED_EXT;
426 ext_param.param_hdr.length =
427 htons(sizeof(sctp_supported_ext_param_t) + num_ext);
428 sctp_addto_chunk(retval, sizeof(sctp_supported_ext_param_t),
429 &ext_param);
430 sctp_addto_param(retval, num_ext, extensions);
431 }
432 if (asoc->peer.prsctp_capable)
433 sctp_addto_chunk(retval, sizeof(prsctp_param), &prsctp_param);
434
435 aiparam.param_hdr.type = SCTP_PARAM_ADAPTATION_LAYER_IND;
436 aiparam.param_hdr.length = htons(sizeof(aiparam));
437 aiparam.adaptation_ind = htonl(sctp_sk(asoc->base.sk)->adaptation_ind);
438 sctp_addto_chunk(retval, sizeof(aiparam), &aiparam);
439
440 if (asoc->peer.auth_capable) {
441 sctp_addto_chunk(retval, ntohs(auth_random->length),
442 auth_random);
443 if (auth_hmacs)
444 sctp_addto_chunk(retval, ntohs(auth_hmacs->length),
445 auth_hmacs);
446 if (auth_chunks)
447 sctp_addto_chunk(retval, ntohs(auth_chunks->length),
448 auth_chunks);
449 }
450
451 /* We need to remove the const qualifier at this point. */
452 retval->asoc = (struct sctp_association *) asoc;
453
454 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
455 *
456 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
457 * HEARTBEAT ACK, * etc.) to the same destination transport
458 * address from which it received the DATA or control chunk
459 * to which it is replying.
460 *
461 * [INIT ACK back to where the INIT came from.]
462 */
463 if (chunk)
464 retval->transport = chunk->transport;
465
466 nomem_chunk:
467 kfree(cookie);
468 nomem_cookie:
469 kfree(addrs.v);
470 return retval;
471 }
472
473 /* 3.3.11 Cookie Echo (COOKIE ECHO) (10):
474 *
475 * This chunk is used only during the initialization of an association.
476 * It is sent by the initiator of an association to its peer to complete
477 * the initialization process. This chunk MUST precede any DATA chunk
478 * sent within the association, but MAY be bundled with one or more DATA
479 * chunks in the same packet.
480 *
481 * 0 1 2 3
482 * 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
483 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
484 * | Type = 10 |Chunk Flags | Length |
485 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
486 * / Cookie /
487 * \ \
488 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
489 *
490 * Chunk Flags: 8 bit
491 *
492 * Set to zero on transmit and ignored on receipt.
493 *
494 * Length: 16 bits (unsigned integer)
495 *
496 * Set to the size of the chunk in bytes, including the 4 bytes of
497 * the chunk header and the size of the Cookie.
498 *
499 * Cookie: variable size
500 *
501 * This field must contain the exact cookie received in the
502 * State Cookie parameter from the previous INIT ACK.
503 *
504 * An implementation SHOULD make the cookie as small as possible
505 * to insure interoperability.
506 */
507 struct sctp_chunk *sctp_make_cookie_echo(const struct sctp_association *asoc,
508 const struct sctp_chunk *chunk)
509 {
510 struct sctp_chunk *retval;
511 void *cookie;
512 int cookie_len;
513
514 cookie = asoc->peer.cookie;
515 cookie_len = asoc->peer.cookie_len;
516
517 /* Build a cookie echo chunk. */
518 retval = sctp_make_chunk(asoc, SCTP_CID_COOKIE_ECHO, 0, cookie_len);
519 if (!retval)
520 goto nodata;
521 retval->subh.cookie_hdr =
522 sctp_addto_chunk(retval, cookie_len, cookie);
523
524 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
525 *
526 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
527 * HEARTBEAT ACK, * etc.) to the same destination transport
528 * address from which it * received the DATA or control chunk
529 * to which it is replying.
530 *
531 * [COOKIE ECHO back to where the INIT ACK came from.]
532 */
533 if (chunk)
534 retval->transport = chunk->transport;
535
536 nodata:
537 return retval;
538 }
539
540 /* 3.3.12 Cookie Acknowledgement (COOKIE ACK) (11):
541 *
542 * This chunk is used only during the initialization of an
543 * association. It is used to acknowledge the receipt of a COOKIE
544 * ECHO chunk. This chunk MUST precede any DATA or SACK chunk sent
545 * within the association, but MAY be bundled with one or more DATA
546 * chunks or SACK chunk in the same SCTP packet.
547 *
548 * 0 1 2 3
549 * 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
550 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
551 * | Type = 11 |Chunk Flags | Length = 4 |
552 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
553 *
554 * Chunk Flags: 8 bits
555 *
556 * Set to zero on transmit and ignored on receipt.
557 */
558 struct sctp_chunk *sctp_make_cookie_ack(const struct sctp_association *asoc,
559 const struct sctp_chunk *chunk)
560 {
561 struct sctp_chunk *retval;
562
563 retval = sctp_make_chunk(asoc, SCTP_CID_COOKIE_ACK, 0, 0);
564
565 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
566 *
567 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
568 * HEARTBEAT ACK, * etc.) to the same destination transport
569 * address from which it * received the DATA or control chunk
570 * to which it is replying.
571 *
572 * [COOKIE ACK back to where the COOKIE ECHO came from.]
573 */
574 if (retval && chunk)
575 retval->transport = chunk->transport;
576
577 return retval;
578 }
579
580 /*
581 * Appendix A: Explicit Congestion Notification:
582 * CWR:
583 *
584 * RFC 2481 details a specific bit for a sender to send in the header of
585 * its next outbound TCP segment to indicate to its peer that it has
586 * reduced its congestion window. This is termed the CWR bit. For
587 * SCTP the same indication is made by including the CWR chunk.
588 * This chunk contains one data element, i.e. the TSN number that
589 * was sent in the ECNE chunk. This element represents the lowest
590 * TSN number in the datagram that was originally marked with the
591 * CE bit.
592 *
593 * 0 1 2 3
594 * 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
595 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
596 * | Chunk Type=13 | Flags=00000000| Chunk Length = 8 |
597 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
598 * | Lowest TSN Number |
599 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
600 *
601 * Note: The CWR is considered a Control chunk.
602 */
603 struct sctp_chunk *sctp_make_cwr(const struct sctp_association *asoc,
604 const __u32 lowest_tsn,
605 const struct sctp_chunk *chunk)
606 {
607 struct sctp_chunk *retval;
608 sctp_cwrhdr_t cwr;
609
610 cwr.lowest_tsn = htonl(lowest_tsn);
611 retval = sctp_make_chunk(asoc, SCTP_CID_ECN_CWR, 0,
612 sizeof(sctp_cwrhdr_t));
613
614 if (!retval)
615 goto nodata;
616
617 retval->subh.ecn_cwr_hdr =
618 sctp_addto_chunk(retval, sizeof(cwr), &cwr);
619
620 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
621 *
622 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
623 * HEARTBEAT ACK, * etc.) to the same destination transport
624 * address from which it * received the DATA or control chunk
625 * to which it is replying.
626 *
627 * [Report a reduced congestion window back to where the ECNE
628 * came from.]
629 */
630 if (chunk)
631 retval->transport = chunk->transport;
632
633 nodata:
634 return retval;
635 }
636
637 /* Make an ECNE chunk. This is a congestion experienced report. */
638 struct sctp_chunk *sctp_make_ecne(const struct sctp_association *asoc,
639 const __u32 lowest_tsn)
640 {
641 struct sctp_chunk *retval;
642 sctp_ecnehdr_t ecne;
643
644 ecne.lowest_tsn = htonl(lowest_tsn);
645 retval = sctp_make_chunk(asoc, SCTP_CID_ECN_ECNE, 0,
646 sizeof(sctp_ecnehdr_t));
647 if (!retval)
648 goto nodata;
649 retval->subh.ecne_hdr =
650 sctp_addto_chunk(retval, sizeof(ecne), &ecne);
651
652 nodata:
653 return retval;
654 }
655
656 /* Make a DATA chunk for the given association from the provided
657 * parameters. However, do not populate the data payload.
658 */
659 struct sctp_chunk *sctp_make_datafrag_empty(struct sctp_association *asoc,
660 const struct sctp_sndrcvinfo *sinfo,
661 int data_len, __u8 flags, __u16 ssn)
662 {
663 struct sctp_chunk *retval;
664 struct sctp_datahdr dp;
665 int chunk_len;
666
667 /* We assign the TSN as LATE as possible, not here when
668 * creating the chunk.
669 */
670 dp.tsn = 0;
671 dp.stream = htons(sinfo->sinfo_stream);
672 dp.ppid = sinfo->sinfo_ppid;
673
674 /* Set the flags for an unordered send. */
675 if (sinfo->sinfo_flags & SCTP_UNORDERED) {
676 flags |= SCTP_DATA_UNORDERED;
677 dp.ssn = 0;
678 } else
679 dp.ssn = htons(ssn);
680
681 chunk_len = sizeof(dp) + data_len;
682 retval = sctp_make_chunk(asoc, SCTP_CID_DATA, flags, chunk_len);
683 if (!retval)
684 goto nodata;
685
686 retval->subh.data_hdr = sctp_addto_chunk(retval, sizeof(dp), &dp);
687 memcpy(&retval->sinfo, sinfo, sizeof(struct sctp_sndrcvinfo));
688
689 nodata:
690 return retval;
691 }
692
693 /* Create a selective ackowledgement (SACK) for the given
694 * association. This reports on which TSN's we've seen to date,
695 * including duplicates and gaps.
696 */
697 struct sctp_chunk *sctp_make_sack(const struct sctp_association *asoc)
698 {
699 struct sctp_chunk *retval;
700 struct sctp_sackhdr sack;
701 int len;
702 __u32 ctsn;
703 __u16 num_gabs, num_dup_tsns;
704 struct sctp_tsnmap *map = (struct sctp_tsnmap *)&asoc->peer.tsn_map;
705
706 ctsn = sctp_tsnmap_get_ctsn(map);
707 SCTP_DEBUG_PRINTK("sackCTSNAck sent: 0x%x.\n", ctsn);
708
709 /* How much room is needed in the chunk? */
710 num_gabs = sctp_tsnmap_num_gabs(map);
711 num_dup_tsns = sctp_tsnmap_num_dups(map);
712
713 /* Initialize the SACK header. */
714 sack.cum_tsn_ack = htonl(ctsn);
715 sack.a_rwnd = htonl(asoc->a_rwnd);
716 sack.num_gap_ack_blocks = htons(num_gabs);
717 sack.num_dup_tsns = htons(num_dup_tsns);
718
719 len = sizeof(sack)
720 + sizeof(struct sctp_gap_ack_block) * num_gabs
721 + sizeof(__u32) * num_dup_tsns;
722
723 /* Create the chunk. */
724 retval = sctp_make_chunk(asoc, SCTP_CID_SACK, 0, len);
725 if (!retval)
726 goto nodata;
727
728 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
729 *
730 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
731 * HEARTBEAT ACK, etc.) to the same destination transport
732 * address from which it received the DATA or control chunk to
733 * which it is replying. This rule should also be followed if
734 * the endpoint is bundling DATA chunks together with the
735 * reply chunk.
736 *
737 * However, when acknowledging multiple DATA chunks received
738 * in packets from different source addresses in a single
739 * SACK, the SACK chunk may be transmitted to one of the
740 * destination transport addresses from which the DATA or
741 * control chunks being acknowledged were received.
742 *
743 * [BUG: We do not implement the following paragraph.
744 * Perhaps we should remember the last transport we used for a
745 * SACK and avoid that (if possible) if we have seen any
746 * duplicates. --piggy]
747 *
748 * When a receiver of a duplicate DATA chunk sends a SACK to a
749 * multi- homed endpoint it MAY be beneficial to vary the
750 * destination address and not use the source address of the
751 * DATA chunk. The reason being that receiving a duplicate
752 * from a multi-homed endpoint might indicate that the return
753 * path (as specified in the source address of the DATA chunk)
754 * for the SACK is broken.
755 *
756 * [Send to the address from which we last received a DATA chunk.]
757 */
758 retval->transport = asoc->peer.last_data_from;
759
760 retval->subh.sack_hdr =
761 sctp_addto_chunk(retval, sizeof(sack), &sack);
762
763 /* Add the gap ack block information. */
764 if (num_gabs)
765 sctp_addto_chunk(retval, sizeof(__u32) * num_gabs,
766 sctp_tsnmap_get_gabs(map));
767
768 /* Add the duplicate TSN information. */
769 if (num_dup_tsns)
770 sctp_addto_chunk(retval, sizeof(__u32) * num_dup_tsns,
771 sctp_tsnmap_get_dups(map));
772
773 nodata:
774 return retval;
775 }
776
777 /* Make a SHUTDOWN chunk. */
778 struct sctp_chunk *sctp_make_shutdown(const struct sctp_association *asoc,
779 const struct sctp_chunk *chunk)
780 {
781 struct sctp_chunk *retval;
782 sctp_shutdownhdr_t shut;
783 __u32 ctsn;
784
785 ctsn = sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map);
786 shut.cum_tsn_ack = htonl(ctsn);
787
788 retval = sctp_make_chunk(asoc, SCTP_CID_SHUTDOWN, 0,
789 sizeof(sctp_shutdownhdr_t));
790 if (!retval)
791 goto nodata;
792
793 retval->subh.shutdown_hdr =
794 sctp_addto_chunk(retval, sizeof(shut), &shut);
795
796 if (chunk)
797 retval->transport = chunk->transport;
798 nodata:
799 return retval;
800 }
801
802 struct sctp_chunk *sctp_make_shutdown_ack(const struct sctp_association *asoc,
803 const struct sctp_chunk *chunk)
804 {
805 struct sctp_chunk *retval;
806
807 retval = sctp_make_chunk(asoc, SCTP_CID_SHUTDOWN_ACK, 0, 0);
808
809 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
810 *
811 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
812 * HEARTBEAT ACK, * etc.) to the same destination transport
813 * address from which it * received the DATA or control chunk
814 * to which it is replying.
815 *
816 * [ACK back to where the SHUTDOWN came from.]
817 */
818 if (retval && chunk)
819 retval->transport = chunk->transport;
820
821 return retval;
822 }
823
824 struct sctp_chunk *sctp_make_shutdown_complete(
825 const struct sctp_association *asoc,
826 const struct sctp_chunk *chunk)
827 {
828 struct sctp_chunk *retval;
829 __u8 flags = 0;
830
831 /* Set the T-bit if we have no association (vtag will be
832 * reflected)
833 */
834 flags |= asoc ? 0 : SCTP_CHUNK_FLAG_T;
835
836 retval = sctp_make_chunk(asoc, SCTP_CID_SHUTDOWN_COMPLETE, flags, 0);
837
838 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
839 *
840 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
841 * HEARTBEAT ACK, * etc.) to the same destination transport
842 * address from which it * received the DATA or control chunk
843 * to which it is replying.
844 *
845 * [Report SHUTDOWN COMPLETE back to where the SHUTDOWN ACK
846 * came from.]
847 */
848 if (retval && chunk)
849 retval->transport = chunk->transport;
850
851 return retval;
852 }
853
854 /* Create an ABORT. Note that we set the T bit if we have no
855 * association, except when responding to an INIT (sctpimpguide 2.41).
856 */
857 struct sctp_chunk *sctp_make_abort(const struct sctp_association *asoc,
858 const struct sctp_chunk *chunk,
859 const size_t hint)
860 {
861 struct sctp_chunk *retval;
862 __u8 flags = 0;
863
864 /* Set the T-bit if we have no association and 'chunk' is not
865 * an INIT (vtag will be reflected).
866 */
867 if (!asoc) {
868 if (chunk && chunk->chunk_hdr &&
869 chunk->chunk_hdr->type == SCTP_CID_INIT)
870 flags = 0;
871 else
872 flags = SCTP_CHUNK_FLAG_T;
873 }
874
875 retval = sctp_make_chunk(asoc, SCTP_CID_ABORT, flags, hint);
876
877 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
878 *
879 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
880 * HEARTBEAT ACK, * etc.) to the same destination transport
881 * address from which it * received the DATA or control chunk
882 * to which it is replying.
883 *
884 * [ABORT back to where the offender came from.]
885 */
886 if (retval && chunk)
887 retval->transport = chunk->transport;
888
889 return retval;
890 }
891
892 /* Helper to create ABORT with a NO_USER_DATA error. */
893 struct sctp_chunk *sctp_make_abort_no_data(
894 const struct sctp_association *asoc,
895 const struct sctp_chunk *chunk, __u32 tsn)
896 {
897 struct sctp_chunk *retval;
898 __be32 payload;
899
900 retval = sctp_make_abort(asoc, chunk, sizeof(sctp_errhdr_t)
901 + sizeof(tsn));
902
903 if (!retval)
904 goto no_mem;
905
906 /* Put the tsn back into network byte order. */
907 payload = htonl(tsn);
908 sctp_init_cause(retval, SCTP_ERROR_NO_DATA, sizeof(payload));
909 sctp_addto_chunk(retval, sizeof(payload), (const void *)&payload);
910
911 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
912 *
913 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
914 * HEARTBEAT ACK, * etc.) to the same destination transport
915 * address from which it * received the DATA or control chunk
916 * to which it is replying.
917 *
918 * [ABORT back to where the offender came from.]
919 */
920 if (chunk)
921 retval->transport = chunk->transport;
922
923 no_mem:
924 return retval;
925 }
926
927 /* Helper to create ABORT with a SCTP_ERROR_USER_ABORT error. */
928 struct sctp_chunk *sctp_make_abort_user(const struct sctp_association *asoc,
929 const struct msghdr *msg,
930 size_t paylen)
931 {
932 struct sctp_chunk *retval;
933 void *payload = NULL;
934 int err;
935
936 retval = sctp_make_abort(asoc, NULL, sizeof(sctp_errhdr_t) + paylen);
937 if (!retval)
938 goto err_chunk;
939
940 if (paylen) {
941 /* Put the msg_iov together into payload. */
942 payload = kmalloc(paylen, GFP_KERNEL);
943 if (!payload)
944 goto err_payload;
945
946 err = memcpy_fromiovec(payload, msg->msg_iov, paylen);
947 if (err < 0)
948 goto err_copy;
949 }
950
951 sctp_init_cause(retval, SCTP_ERROR_USER_ABORT, paylen);
952 sctp_addto_chunk(retval, paylen, payload);
953
954 if (paylen)
955 kfree(payload);
956
957 return retval;
958
959 err_copy:
960 kfree(payload);
961 err_payload:
962 sctp_chunk_free(retval);
963 retval = NULL;
964 err_chunk:
965 return retval;
966 }
967
968 /* Append bytes to the end of a parameter. Will panic if chunk is not big
969 * enough.
970 */
971 static void *sctp_addto_param(struct sctp_chunk *chunk, int len,
972 const void *data)
973 {
974 void *target;
975 int chunklen = ntohs(chunk->chunk_hdr->length);
976
977 target = skb_put(chunk->skb, len);
978
979 memcpy(target, data, len);
980
981 /* Adjust the chunk length field. */
982 chunk->chunk_hdr->length = htons(chunklen + len);
983 chunk->chunk_end = skb_tail_pointer(chunk->skb);
984
985 return target;
986 }
987
988 /* Make an ABORT chunk with a PROTOCOL VIOLATION cause code. */
989 struct sctp_chunk *sctp_make_abort_violation(
990 const struct sctp_association *asoc,
991 const struct sctp_chunk *chunk,
992 const __u8 *payload,
993 const size_t paylen)
994 {
995 struct sctp_chunk *retval;
996 struct sctp_paramhdr phdr;
997
998 retval = sctp_make_abort(asoc, chunk, sizeof(sctp_errhdr_t) + paylen
999 + sizeof(sctp_paramhdr_t));
1000 if (!retval)
1001 goto end;
1002
1003 sctp_init_cause(retval, SCTP_ERROR_PROTO_VIOLATION, paylen
1004 + sizeof(sctp_paramhdr_t));
1005
1006 phdr.type = htons(chunk->chunk_hdr->type);
1007 phdr.length = chunk->chunk_hdr->length;
1008 sctp_addto_chunk(retval, paylen, payload);
1009 sctp_addto_param(retval, sizeof(sctp_paramhdr_t), &phdr);
1010
1011 end:
1012 return retval;
1013 }
1014
1015 struct sctp_chunk *sctp_make_violation_paramlen(
1016 const struct sctp_association *asoc,
1017 const struct sctp_chunk *chunk,
1018 struct sctp_paramhdr *param)
1019 {
1020 struct sctp_chunk *retval;
1021 static const char error[] = "The following parameter had invalid length:";
1022 size_t payload_len = sizeof(error) + sizeof(sctp_errhdr_t) +
1023 sizeof(sctp_paramhdr_t);
1024
1025 retval = sctp_make_abort(asoc, chunk, payload_len);
1026 if (!retval)
1027 goto nodata;
1028
1029 sctp_init_cause(retval, SCTP_ERROR_PROTO_VIOLATION,
1030 sizeof(error) + sizeof(sctp_paramhdr_t));
1031 sctp_addto_chunk(retval, sizeof(error), error);
1032 sctp_addto_param(retval, sizeof(sctp_paramhdr_t), param);
1033
1034 nodata:
1035 return retval;
1036 }
1037
1038 /* Make a HEARTBEAT chunk. */
1039 struct sctp_chunk *sctp_make_heartbeat(const struct sctp_association *asoc,
1040 const struct sctp_transport *transport,
1041 const void *payload, const size_t paylen)
1042 {
1043 struct sctp_chunk *retval = sctp_make_chunk(asoc, SCTP_CID_HEARTBEAT,
1044 0, paylen);
1045
1046 if (!retval)
1047 goto nodata;
1048
1049 /* Cast away the 'const', as this is just telling the chunk
1050 * what transport it belongs to.
1051 */
1052 retval->transport = (struct sctp_transport *) transport;
1053 retval->subh.hbs_hdr = sctp_addto_chunk(retval, paylen, payload);
1054
1055 nodata:
1056 return retval;
1057 }
1058
1059 struct sctp_chunk *sctp_make_heartbeat_ack(const struct sctp_association *asoc,
1060 const struct sctp_chunk *chunk,
1061 const void *payload, const size_t paylen)
1062 {
1063 struct sctp_chunk *retval;
1064
1065 retval = sctp_make_chunk(asoc, SCTP_CID_HEARTBEAT_ACK, 0, paylen);
1066 if (!retval)
1067 goto nodata;
1068
1069 retval->subh.hbs_hdr = sctp_addto_chunk(retval, paylen, payload);
1070
1071 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
1072 *
1073 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
1074 * HEARTBEAT ACK, * etc.) to the same destination transport
1075 * address from which it * received the DATA or control chunk
1076 * to which it is replying.
1077 *
1078 * [HBACK back to where the HEARTBEAT came from.]
1079 */
1080 if (chunk)
1081 retval->transport = chunk->transport;
1082
1083 nodata:
1084 return retval;
1085 }
1086
1087 /* Create an Operation Error chunk with the specified space reserved.
1088 * This routine can be used for containing multiple causes in the chunk.
1089 */
1090 static struct sctp_chunk *sctp_make_op_error_space(
1091 const struct sctp_association *asoc,
1092 const struct sctp_chunk *chunk,
1093 size_t size)
1094 {
1095 struct sctp_chunk *retval;
1096
1097 retval = sctp_make_chunk(asoc, SCTP_CID_ERROR, 0,
1098 sizeof(sctp_errhdr_t) + size);
1099 if (!retval)
1100 goto nodata;
1101
1102 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
1103 *
1104 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
1105 * HEARTBEAT ACK, etc.) to the same destination transport
1106 * address from which it received the DATA or control chunk
1107 * to which it is replying.
1108 *
1109 */
1110 if (chunk)
1111 retval->transport = chunk->transport;
1112
1113 nodata:
1114 return retval;
1115 }
1116
1117 /* Create an Operation Error chunk. */
1118 struct sctp_chunk *sctp_make_op_error(const struct sctp_association *asoc,
1119 const struct sctp_chunk *chunk,
1120 __be16 cause_code, const void *payload,
1121 size_t paylen)
1122 {
1123 struct sctp_chunk *retval;
1124
1125 retval = sctp_make_op_error_space(asoc, chunk, paylen);
1126 if (!retval)
1127 goto nodata;
1128
1129 sctp_init_cause(retval, cause_code, paylen);
1130 sctp_addto_chunk(retval, paylen, payload);
1131
1132 nodata:
1133 return retval;
1134 }
1135
1136 struct sctp_chunk *sctp_make_auth(const struct sctp_association *asoc)
1137 {
1138 struct sctp_chunk *retval;
1139 struct sctp_hmac *hmac_desc;
1140 struct sctp_authhdr auth_hdr;
1141 __u8 *hmac;
1142
1143 /* Get the first hmac that the peer told us to use */
1144 hmac_desc = sctp_auth_asoc_get_hmac(asoc);
1145 if (unlikely(!hmac_desc))
1146 return NULL;
1147
1148 retval = sctp_make_chunk(asoc, SCTP_CID_AUTH, 0,
1149 hmac_desc->hmac_len + sizeof(sctp_authhdr_t));
1150 if (!retval)
1151 return NULL;
1152
1153 auth_hdr.hmac_id = htons(hmac_desc->hmac_id);
1154 auth_hdr.shkey_id = htons(asoc->active_key_id);
1155
1156 retval->subh.auth_hdr = sctp_addto_chunk(retval, sizeof(sctp_authhdr_t),
1157 &auth_hdr);
1158
1159 hmac = skb_put(retval->skb, hmac_desc->hmac_len);
1160 memset(hmac, 0, hmac_desc->hmac_len);
1161
1162 /* Adjust the chunk header to include the empty MAC */
1163 retval->chunk_hdr->length =
1164 htons(ntohs(retval->chunk_hdr->length) + hmac_desc->hmac_len);
1165 retval->chunk_end = skb_tail_pointer(retval->skb);
1166
1167 return retval;
1168 }
1169
1170
1171 /********************************************************************
1172 * 2nd Level Abstractions
1173 ********************************************************************/
1174
1175 /* Turn an skb into a chunk.
1176 * FIXME: Eventually move the structure directly inside the skb->cb[].
1177 */
1178 struct sctp_chunk *sctp_chunkify(struct sk_buff *skb,
1179 const struct sctp_association *asoc,
1180 struct sock *sk)
1181 {
1182 struct sctp_chunk *retval;
1183
1184 retval = kmem_cache_zalloc(sctp_chunk_cachep, GFP_ATOMIC);
1185
1186 if (!retval)
1187 goto nodata;
1188
1189 if (!sk) {
1190 SCTP_DEBUG_PRINTK("chunkifying skb %p w/o an sk\n", skb);
1191 }
1192
1193 INIT_LIST_HEAD(&retval->list);
1194 retval->skb = skb;
1195 retval->asoc = (struct sctp_association *)asoc;
1196 retval->resent = 0;
1197 retval->has_tsn = 0;
1198 retval->has_ssn = 0;
1199 retval->rtt_in_progress = 0;
1200 retval->sent_at = 0;
1201 retval->singleton = 1;
1202 retval->end_of_packet = 0;
1203 retval->ecn_ce_done = 0;
1204 retval->pdiscard = 0;
1205
1206 /* sctpimpguide-05.txt Section 2.8.2
1207 * M1) Each time a new DATA chunk is transmitted
1208 * set the 'TSN.Missing.Report' count for that TSN to 0. The
1209 * 'TSN.Missing.Report' count will be used to determine missing chunks
1210 * and when to fast retransmit.
1211 */
1212 retval->tsn_missing_report = 0;
1213 retval->tsn_gap_acked = 0;
1214 retval->fast_retransmit = 0;
1215
1216 /* If this is a fragmented message, track all fragments
1217 * of the message (for SEND_FAILED).
1218 */
1219 retval->msg = NULL;
1220
1221 /* Polish the bead hole. */
1222 INIT_LIST_HEAD(&retval->transmitted_list);
1223 INIT_LIST_HEAD(&retval->frag_list);
1224 SCTP_DBG_OBJCNT_INC(chunk);
1225 atomic_set(&retval->refcnt, 1);
1226
1227 nodata:
1228 return retval;
1229 }
1230
1231 /* Set chunk->source and dest based on the IP header in chunk->skb. */
1232 void sctp_init_addrs(struct sctp_chunk *chunk, union sctp_addr *src,
1233 union sctp_addr *dest)
1234 {
1235 memcpy(&chunk->source, src, sizeof(union sctp_addr));
1236 memcpy(&chunk->dest, dest, sizeof(union sctp_addr));
1237 }
1238
1239 /* Extract the source address from a chunk. */
1240 const union sctp_addr *sctp_source(const struct sctp_chunk *chunk)
1241 {
1242 /* If we have a known transport, use that. */
1243 if (chunk->transport) {
1244 return &chunk->transport->ipaddr;
1245 } else {
1246 /* Otherwise, extract it from the IP header. */
1247 return &chunk->source;
1248 }
1249 }
1250
1251 /* Create a new chunk, setting the type and flags headers from the
1252 * arguments, reserving enough space for a 'paylen' byte payload.
1253 */
1254 SCTP_STATIC
1255 struct sctp_chunk *sctp_make_chunk(const struct sctp_association *asoc,
1256 __u8 type, __u8 flags, int paylen)
1257 {
1258 struct sctp_chunk *retval;
1259 sctp_chunkhdr_t *chunk_hdr;
1260 struct sk_buff *skb;
1261 struct sock *sk;
1262
1263 /* No need to allocate LL here, as this is only a chunk. */
1264 skb = alloc_skb(WORD_ROUND(sizeof(sctp_chunkhdr_t) + paylen),
1265 GFP_ATOMIC);
1266 if (!skb)
1267 goto nodata;
1268
1269 /* Make room for the chunk header. */
1270 chunk_hdr = (sctp_chunkhdr_t *)skb_put(skb, sizeof(sctp_chunkhdr_t));
1271 chunk_hdr->type = type;
1272 chunk_hdr->flags = flags;
1273 chunk_hdr->length = htons(sizeof(sctp_chunkhdr_t));
1274
1275 sk = asoc ? asoc->base.sk : NULL;
1276 retval = sctp_chunkify(skb, asoc, sk);
1277 if (!retval) {
1278 kfree_skb(skb);
1279 goto nodata;
1280 }
1281
1282 retval->chunk_hdr = chunk_hdr;
1283 retval->chunk_end = ((__u8 *)chunk_hdr) + sizeof(struct sctp_chunkhdr);
1284
1285 /* Determine if the chunk needs to be authenticated */
1286 if (sctp_auth_send_cid(type, asoc))
1287 retval->auth = 1;
1288
1289 /* Set the skb to the belonging sock for accounting. */
1290 skb->sk = sk;
1291
1292 return retval;
1293 nodata:
1294 return NULL;
1295 }
1296
1297
1298 /* Release the memory occupied by a chunk. */
1299 static void sctp_chunk_destroy(struct sctp_chunk *chunk)
1300 {
1301 BUG_ON(!list_empty(&chunk->list));
1302 list_del_init(&chunk->transmitted_list);
1303
1304 /* Free the chunk skb data and the SCTP_chunk stub itself. */
1305 dev_kfree_skb(chunk->skb);
1306
1307 SCTP_DBG_OBJCNT_DEC(chunk);
1308 kmem_cache_free(sctp_chunk_cachep, chunk);
1309 }
1310
1311 /* Possibly, free the chunk. */
1312 void sctp_chunk_free(struct sctp_chunk *chunk)
1313 {
1314 /* Release our reference on the message tracker. */
1315 if (chunk->msg)
1316 sctp_datamsg_put(chunk->msg);
1317
1318 sctp_chunk_put(chunk);
1319 }
1320
1321 /* Grab a reference to the chunk. */
1322 void sctp_chunk_hold(struct sctp_chunk *ch)
1323 {
1324 atomic_inc(&ch->refcnt);
1325 }
1326
1327 /* Release a reference to the chunk. */
1328 void sctp_chunk_put(struct sctp_chunk *ch)
1329 {
1330 if (atomic_dec_and_test(&ch->refcnt))
1331 sctp_chunk_destroy(ch);
1332 }
1333
1334 /* Append bytes to the end of a chunk. Will panic if chunk is not big
1335 * enough.
1336 */
1337 void *sctp_addto_chunk(struct sctp_chunk *chunk, int len, const void *data)
1338 {
1339 void *target;
1340 void *padding;
1341 int chunklen = ntohs(chunk->chunk_hdr->length);
1342 int padlen = WORD_ROUND(chunklen) - chunklen;
1343
1344 padding = skb_put(chunk->skb, padlen);
1345 target = skb_put(chunk->skb, len);
1346
1347 memset(padding, 0, padlen);
1348 memcpy(target, data, len);
1349
1350 /* Adjust the chunk length field. */
1351 chunk->chunk_hdr->length = htons(chunklen + padlen + len);
1352 chunk->chunk_end = skb_tail_pointer(chunk->skb);
1353
1354 return target;
1355 }
1356
1357 /* Append bytes from user space to the end of a chunk. Will panic if
1358 * chunk is not big enough.
1359 * Returns a kernel err value.
1360 */
1361 int sctp_user_addto_chunk(struct sctp_chunk *chunk, int off, int len,
1362 struct iovec *data)
1363 {
1364 __u8 *target;
1365 int err = 0;
1366
1367 /* Make room in chunk for data. */
1368 target = skb_put(chunk->skb, len);
1369
1370 /* Copy data (whole iovec) into chunk */
1371 if ((err = memcpy_fromiovecend(target, data, off, len)))
1372 goto out;
1373
1374 /* Adjust the chunk length field. */
1375 chunk->chunk_hdr->length =
1376 htons(ntohs(chunk->chunk_hdr->length) + len);
1377 chunk->chunk_end = skb_tail_pointer(chunk->skb);
1378
1379 out:
1380 return err;
1381 }
1382
1383 /* Helper function to assign a TSN if needed. This assumes that both
1384 * the data_hdr and association have already been assigned.
1385 */
1386 void sctp_chunk_assign_ssn(struct sctp_chunk *chunk)
1387 {
1388 struct sctp_datamsg *msg;
1389 struct sctp_chunk *lchunk;
1390 struct sctp_stream *stream;
1391 __u16 ssn;
1392 __u16 sid;
1393
1394 if (chunk->has_ssn)
1395 return;
1396
1397 /* All fragments will be on the same stream */
1398 sid = ntohs(chunk->subh.data_hdr->stream);
1399 stream = &chunk->asoc->ssnmap->out;
1400
1401 /* Now assign the sequence number to the entire message.
1402 * All fragments must have the same stream sequence number.
1403 */
1404 msg = chunk->msg;
1405 list_for_each_entry(lchunk, &msg->chunks, frag_list) {
1406 if (lchunk->chunk_hdr->flags & SCTP_DATA_UNORDERED) {
1407 ssn = 0;
1408 } else {
1409 if (lchunk->chunk_hdr->flags & SCTP_DATA_LAST_FRAG)
1410 ssn = sctp_ssn_next(stream, sid);
1411 else
1412 ssn = sctp_ssn_peek(stream, sid);
1413 }
1414
1415 lchunk->subh.data_hdr->ssn = htons(ssn);
1416 lchunk->has_ssn = 1;
1417 }
1418 }
1419
1420 /* Helper function to assign a TSN if needed. This assumes that both
1421 * the data_hdr and association have already been assigned.
1422 */
1423 void sctp_chunk_assign_tsn(struct sctp_chunk *chunk)
1424 {
1425 if (!chunk->has_tsn) {
1426 /* This is the last possible instant to
1427 * assign a TSN.
1428 */
1429 chunk->subh.data_hdr->tsn =
1430 htonl(sctp_association_get_next_tsn(chunk->asoc));
1431 chunk->has_tsn = 1;
1432 }
1433 }
1434
1435 /* Create a CLOSED association to use with an incoming packet. */
1436 struct sctp_association *sctp_make_temp_asoc(const struct sctp_endpoint *ep,
1437 struct sctp_chunk *chunk,
1438 gfp_t gfp)
1439 {
1440 struct sctp_association *asoc;
1441 struct sk_buff *skb;
1442 sctp_scope_t scope;
1443 struct sctp_af *af;
1444
1445 /* Create the bare association. */
1446 scope = sctp_scope(sctp_source(chunk));
1447 asoc = sctp_association_new(ep, ep->base.sk, scope, gfp);
1448 if (!asoc)
1449 goto nodata;
1450 asoc->temp = 1;
1451 skb = chunk->skb;
1452 /* Create an entry for the source address of the packet. */
1453 af = sctp_get_af_specific(ipver2af(ip_hdr(skb)->version));
1454 if (unlikely(!af))
1455 goto fail;
1456 af->from_skb(&asoc->c.peer_addr, skb, 1);
1457 nodata:
1458 return asoc;
1459
1460 fail:
1461 sctp_association_free(asoc);
1462 return NULL;
1463 }
1464
1465 /* Build a cookie representing asoc.
1466 * This INCLUDES the param header needed to put the cookie in the INIT ACK.
1467 */
1468 static sctp_cookie_param_t *sctp_pack_cookie(const struct sctp_endpoint *ep,
1469 const struct sctp_association *asoc,
1470 const struct sctp_chunk *init_chunk,
1471 int *cookie_len,
1472 const __u8 *raw_addrs, int addrs_len)
1473 {
1474 sctp_cookie_param_t *retval;
1475 struct sctp_signed_cookie *cookie;
1476 struct scatterlist sg;
1477 int headersize, bodysize;
1478 unsigned int keylen;
1479 char *key;
1480
1481 /* Header size is static data prior to the actual cookie, including
1482 * any padding.
1483 */
1484 headersize = sizeof(sctp_paramhdr_t) +
1485 (sizeof(struct sctp_signed_cookie) -
1486 sizeof(struct sctp_cookie));
1487 bodysize = sizeof(struct sctp_cookie)
1488 + ntohs(init_chunk->chunk_hdr->length) + addrs_len;
1489
1490 /* Pad out the cookie to a multiple to make the signature
1491 * functions simpler to write.
1492 */
1493 if (bodysize % SCTP_COOKIE_MULTIPLE)
1494 bodysize += SCTP_COOKIE_MULTIPLE
1495 - (bodysize % SCTP_COOKIE_MULTIPLE);
1496 *cookie_len = headersize + bodysize;
1497
1498 /* Clear this memory since we are sending this data structure
1499 * out on the network.
1500 */
1501 retval = kzalloc(*cookie_len, GFP_ATOMIC);
1502 if (!retval)
1503 goto nodata;
1504
1505 cookie = (struct sctp_signed_cookie *) retval->body;
1506
1507 /* Set up the parameter header. */
1508 retval->p.type = SCTP_PARAM_STATE_COOKIE;
1509 retval->p.length = htons(*cookie_len);
1510
1511 /* Copy the cookie part of the association itself. */
1512 cookie->c = asoc->c;
1513 /* Save the raw address list length in the cookie. */
1514 cookie->c.raw_addr_list_len = addrs_len;
1515
1516 /* Remember PR-SCTP capability. */
1517 cookie->c.prsctp_capable = asoc->peer.prsctp_capable;
1518
1519 /* Save adaptation indication in the cookie. */
1520 cookie->c.adaptation_ind = asoc->peer.adaptation_ind;
1521
1522 /* Set an expiration time for the cookie. */
1523 do_gettimeofday(&cookie->c.expiration);
1524 TIMEVAL_ADD(asoc->cookie_life, cookie->c.expiration);
1525
1526 /* Copy the peer's init packet. */
1527 memcpy(&cookie->c.peer_init[0], init_chunk->chunk_hdr,
1528 ntohs(init_chunk->chunk_hdr->length));
1529
1530 /* Copy the raw local address list of the association. */
1531 memcpy((__u8 *)&cookie->c.peer_init[0] +
1532 ntohs(init_chunk->chunk_hdr->length), raw_addrs, addrs_len);
1533
1534 if (sctp_sk(ep->base.sk)->hmac) {
1535 struct hash_desc desc;
1536
1537 /* Sign the message. */
1538 sg_init_one(&sg, &cookie->c, bodysize);
1539 keylen = SCTP_SECRET_SIZE;
1540 key = (char *)ep->secret_key[ep->current_key];
1541 desc.tfm = sctp_sk(ep->base.sk)->hmac;
1542 desc.flags = 0;
1543
1544 if (crypto_hash_setkey(desc.tfm, key, keylen) ||
1545 crypto_hash_digest(&desc, &sg, bodysize, cookie->signature))
1546 goto free_cookie;
1547 }
1548
1549 return retval;
1550
1551 free_cookie:
1552 kfree(retval);
1553 nodata:
1554 *cookie_len = 0;
1555 return NULL;
1556 }
1557
1558 /* Unpack the cookie from COOKIE ECHO chunk, recreating the association. */
1559 struct sctp_association *sctp_unpack_cookie(
1560 const struct sctp_endpoint *ep,
1561 const struct sctp_association *asoc,
1562 struct sctp_chunk *chunk, gfp_t gfp,
1563 int *error, struct sctp_chunk **errp)
1564 {
1565 struct sctp_association *retval = NULL;
1566 struct sctp_signed_cookie *cookie;
1567 struct sctp_cookie *bear_cookie;
1568 int headersize, bodysize, fixed_size;
1569 __u8 *digest = ep->digest;
1570 struct scatterlist sg;
1571 unsigned int keylen, len;
1572 char *key;
1573 sctp_scope_t scope;
1574 struct sk_buff *skb = chunk->skb;
1575 struct timeval tv;
1576 struct hash_desc desc;
1577
1578 /* Header size is static data prior to the actual cookie, including
1579 * any padding.
1580 */
1581 headersize = sizeof(sctp_chunkhdr_t) +
1582 (sizeof(struct sctp_signed_cookie) -
1583 sizeof(struct sctp_cookie));
1584 bodysize = ntohs(chunk->chunk_hdr->length) - headersize;
1585 fixed_size = headersize + sizeof(struct sctp_cookie);
1586
1587 /* Verify that the chunk looks like it even has a cookie.
1588 * There must be enough room for our cookie and our peer's
1589 * INIT chunk.
1590 */
1591 len = ntohs(chunk->chunk_hdr->length);
1592 if (len < fixed_size + sizeof(struct sctp_chunkhdr))
1593 goto malformed;
1594
1595 /* Verify that the cookie has been padded out. */
1596 if (bodysize % SCTP_COOKIE_MULTIPLE)
1597 goto malformed;
1598
1599 /* Process the cookie. */
1600 cookie = chunk->subh.cookie_hdr;
1601 bear_cookie = &cookie->c;
1602
1603 if (!sctp_sk(ep->base.sk)->hmac)
1604 goto no_hmac;
1605
1606 /* Check the signature. */
1607 keylen = SCTP_SECRET_SIZE;
1608 sg_init_one(&sg, bear_cookie, bodysize);
1609 key = (char *)ep->secret_key[ep->current_key];
1610 desc.tfm = sctp_sk(ep->base.sk)->hmac;
1611 desc.flags = 0;
1612
1613 memset(digest, 0x00, SCTP_SIGNATURE_SIZE);
1614 if (crypto_hash_setkey(desc.tfm, key, keylen) ||
1615 crypto_hash_digest(&desc, &sg, bodysize, digest)) {
1616 *error = -SCTP_IERROR_NOMEM;
1617 goto fail;
1618 }
1619
1620 if (memcmp(digest, cookie->signature, SCTP_SIGNATURE_SIZE)) {
1621 /* Try the previous key. */
1622 key = (char *)ep->secret_key[ep->last_key];
1623 memset(digest, 0x00, SCTP_SIGNATURE_SIZE);
1624 if (crypto_hash_setkey(desc.tfm, key, keylen) ||
1625 crypto_hash_digest(&desc, &sg, bodysize, digest)) {
1626 *error = -SCTP_IERROR_NOMEM;
1627 goto fail;
1628 }
1629
1630 if (memcmp(digest, cookie->signature, SCTP_SIGNATURE_SIZE)) {
1631 /* Yikes! Still bad signature! */
1632 *error = -SCTP_IERROR_BAD_SIG;
1633 goto fail;
1634 }
1635 }
1636
1637 no_hmac:
1638 /* IG Section 2.35.2:
1639 * 3) Compare the port numbers and the verification tag contained
1640 * within the COOKIE ECHO chunk to the actual port numbers and the
1641 * verification tag within the SCTP common header of the received
1642 * packet. If these values do not match the packet MUST be silently
1643 * discarded,
1644 */
1645 if (ntohl(chunk->sctp_hdr->vtag) != bear_cookie->my_vtag) {
1646 *error = -SCTP_IERROR_BAD_TAG;
1647 goto fail;
1648 }
1649
1650 if (chunk->sctp_hdr->source != bear_cookie->peer_addr.v4.sin_port ||
1651 ntohs(chunk->sctp_hdr->dest) != bear_cookie->my_port) {
1652 *error = -SCTP_IERROR_BAD_PORTS;
1653 goto fail;
1654 }
1655
1656 /* Check to see if the cookie is stale. If there is already
1657 * an association, there is no need to check cookie's expiration
1658 * for init collision case of lost COOKIE ACK.
1659 * If skb has been timestamped, then use the stamp, otherwise
1660 * use current time. This introduces a small possibility that
1661 * that a cookie may be considered expired, but his would only slow
1662 * down the new association establishment instead of every packet.
1663 */
1664 if (sock_flag(ep->base.sk, SOCK_TIMESTAMP))
1665 skb_get_timestamp(skb, &tv);
1666 else
1667 do_gettimeofday(&tv);
1668
1669 if (!asoc && tv_lt(bear_cookie->expiration, tv)) {
1670 /*
1671 * Section 3.3.10.3 Stale Cookie Error (3)
1672 *
1673 * Cause of error
1674 * ---------------
1675 * Stale Cookie Error: Indicates the receipt of a valid State
1676 * Cookie that has expired.
1677 */
1678 len = ntohs(chunk->chunk_hdr->length);
1679 *errp = sctp_make_op_error_space(asoc, chunk, len);
1680 if (*errp) {
1681 suseconds_t usecs = (tv.tv_sec -
1682 bear_cookie->expiration.tv_sec) * 1000000L +
1683 tv.tv_usec - bear_cookie->expiration.tv_usec;
1684 __be32 n = htonl(usecs);
1685
1686 sctp_init_cause(*errp, SCTP_ERROR_STALE_COOKIE,
1687 sizeof(n));
1688 sctp_addto_chunk(*errp, sizeof(n), &n);
1689 *error = -SCTP_IERROR_STALE_COOKIE;
1690 } else
1691 *error = -SCTP_IERROR_NOMEM;
1692
1693 goto fail;
1694 }
1695
1696 /* Make a new base association. */
1697 scope = sctp_scope(sctp_source(chunk));
1698 retval = sctp_association_new(ep, ep->base.sk, scope, gfp);
1699 if (!retval) {
1700 *error = -SCTP_IERROR_NOMEM;
1701 goto fail;
1702 }
1703
1704 /* Set up our peer's port number. */
1705 retval->peer.port = ntohs(chunk->sctp_hdr->source);
1706
1707 /* Populate the association from the cookie. */
1708 memcpy(&retval->c, bear_cookie, sizeof(*bear_cookie));
1709
1710 if (sctp_assoc_set_bind_addr_from_cookie(retval, bear_cookie,
1711 GFP_ATOMIC) < 0) {
1712 *error = -SCTP_IERROR_NOMEM;
1713 goto fail;
1714 }
1715
1716 /* Also, add the destination address. */
1717 if (list_empty(&retval->base.bind_addr.address_list)) {
1718 sctp_add_bind_addr(&retval->base.bind_addr, &chunk->dest,
1719 SCTP_ADDR_SRC, GFP_ATOMIC);
1720 }
1721
1722 retval->next_tsn = retval->c.initial_tsn;
1723 retval->ctsn_ack_point = retval->next_tsn - 1;
1724 retval->addip_serial = retval->c.initial_tsn;
1725 retval->adv_peer_ack_point = retval->ctsn_ack_point;
1726 retval->peer.prsctp_capable = retval->c.prsctp_capable;
1727 retval->peer.adaptation_ind = retval->c.adaptation_ind;
1728
1729 /* The INIT stuff will be done by the side effects. */
1730 return retval;
1731
1732 fail:
1733 if (retval)
1734 sctp_association_free(retval);
1735
1736 return NULL;
1737
1738 malformed:
1739 /* Yikes! The packet is either corrupt or deliberately
1740 * malformed.
1741 */
1742 *error = -SCTP_IERROR_MALFORMED;
1743 goto fail;
1744 }
1745
1746 /********************************************************************
1747 * 3rd Level Abstractions
1748 ********************************************************************/
1749
1750 struct __sctp_missing {
1751 __be32 num_missing;
1752 __be16 type;
1753 } __attribute__((packed));
1754
1755 /*
1756 * Report a missing mandatory parameter.
1757 */
1758 static int sctp_process_missing_param(const struct sctp_association *asoc,
1759 sctp_param_t paramtype,
1760 struct sctp_chunk *chunk,
1761 struct sctp_chunk **errp)
1762 {
1763 struct __sctp_missing report;
1764 __u16 len;
1765
1766 len = WORD_ROUND(sizeof(report));
1767
1768 /* Make an ERROR chunk, preparing enough room for
1769 * returning multiple unknown parameters.
1770 */
1771 if (!*errp)
1772 *errp = sctp_make_op_error_space(asoc, chunk, len);
1773
1774 if (*errp) {
1775 report.num_missing = htonl(1);
1776 report.type = paramtype;
1777 sctp_init_cause(*errp, SCTP_ERROR_MISS_PARAM,
1778 sizeof(report));
1779 sctp_addto_chunk(*errp, sizeof(report), &report);
1780 }
1781
1782 /* Stop processing this chunk. */
1783 return 0;
1784 }
1785
1786 /* Report an Invalid Mandatory Parameter. */
1787 static int sctp_process_inv_mandatory(const struct sctp_association *asoc,
1788 struct sctp_chunk *chunk,
1789 struct sctp_chunk **errp)
1790 {
1791 /* Invalid Mandatory Parameter Error has no payload. */
1792
1793 if (!*errp)
1794 *errp = sctp_make_op_error_space(asoc, chunk, 0);
1795
1796 if (*errp)
1797 sctp_init_cause(*errp, SCTP_ERROR_INV_PARAM, 0);
1798
1799 /* Stop processing this chunk. */
1800 return 0;
1801 }
1802
1803 static int sctp_process_inv_paramlength(const struct sctp_association *asoc,
1804 struct sctp_paramhdr *param,
1805 const struct sctp_chunk *chunk,
1806 struct sctp_chunk **errp)
1807 {
1808 /* This is a fatal error. Any accumulated non-fatal errors are
1809 * not reported.
1810 */
1811 if (*errp)
1812 sctp_chunk_free(*errp);
1813
1814 /* Create an error chunk and fill it in with our payload. */
1815 *errp = sctp_make_violation_paramlen(asoc, chunk, param);
1816
1817 return 0;
1818 }
1819
1820
1821 /* Do not attempt to handle the HOST_NAME parm. However, do
1822 * send back an indicator to the peer.
1823 */
1824 static int sctp_process_hn_param(const struct sctp_association *asoc,
1825 union sctp_params param,
1826 struct sctp_chunk *chunk,
1827 struct sctp_chunk **errp)
1828 {
1829 __u16 len = ntohs(param.p->length);
1830
1831 /* Processing of the HOST_NAME parameter will generate an
1832 * ABORT. If we've accumulated any non-fatal errors, they
1833 * would be unrecognized parameters and we should not include
1834 * them in the ABORT.
1835 */
1836 if (*errp)
1837 sctp_chunk_free(*errp);
1838
1839 *errp = sctp_make_op_error_space(asoc, chunk, len);
1840
1841 if (*errp) {
1842 sctp_init_cause(*errp, SCTP_ERROR_DNS_FAILED, len);
1843 sctp_addto_chunk(*errp, len, param.v);
1844 }
1845
1846 /* Stop processing this chunk. */
1847 return 0;
1848 }
1849
1850 static int sctp_verify_ext_param(union sctp_params param)
1851 {
1852 __u16 num_ext = ntohs(param.p->length) - sizeof(sctp_paramhdr_t);
1853 int have_auth = 0;
1854 int have_asconf = 0;
1855 int i;
1856
1857 for (i = 0; i < num_ext; i++) {
1858 switch (param.ext->chunks[i]) {
1859 case SCTP_CID_AUTH:
1860 have_auth = 1;
1861 break;
1862 case SCTP_CID_ASCONF:
1863 case SCTP_CID_ASCONF_ACK:
1864 have_asconf = 1;
1865 break;
1866 }
1867 }
1868
1869 /* ADD-IP Security: The draft requires us to ABORT or ignore the
1870 * INIT/INIT-ACK if ADD-IP is listed, but AUTH is not. Do this
1871 * only if ADD-IP is turned on and we are not backward-compatible
1872 * mode.
1873 */
1874 if (sctp_addip_noauth)
1875 return 1;
1876
1877 if (sctp_addip_enable && !have_auth && have_asconf)
1878 return 0;
1879
1880 return 1;
1881 }
1882
1883 static void sctp_process_ext_param(struct sctp_association *asoc,
1884 union sctp_params param)
1885 {
1886 __u16 num_ext = ntohs(param.p->length) - sizeof(sctp_paramhdr_t);
1887 int i;
1888
1889 for (i = 0; i < num_ext; i++) {
1890 switch (param.ext->chunks[i]) {
1891 case SCTP_CID_FWD_TSN:
1892 if (sctp_prsctp_enable &&
1893 !asoc->peer.prsctp_capable)
1894 asoc->peer.prsctp_capable = 1;
1895 break;
1896 case SCTP_CID_AUTH:
1897 /* if the peer reports AUTH, assume that he
1898 * supports AUTH.
1899 */
1900 if (sctp_auth_enable)
1901 asoc->peer.auth_capable = 1;
1902 break;
1903 case SCTP_CID_ASCONF:
1904 case SCTP_CID_ASCONF_ACK:
1905 if (sctp_addip_enable)
1906 asoc->peer.asconf_capable = 1;
1907 break;
1908 default:
1909 break;
1910 }
1911 }
1912 }
1913
1914 /* RFC 3.2.1 & the Implementers Guide 2.2.
1915 *
1916 * The Parameter Types are encoded such that the
1917 * highest-order two bits specify the action that must be
1918 * taken if the processing endpoint does not recognize the
1919 * Parameter Type.
1920 *
1921 * 00 - Stop processing this parameter; do not process any further
1922 * parameters within this chunk
1923 *
1924 * 01 - Stop processing this parameter, do not process any further
1925 * parameters within this chunk, and report the unrecognized
1926 * parameter in an 'Unrecognized Parameter' ERROR chunk.
1927 *
1928 * 10 - Skip this parameter and continue processing.
1929 *
1930 * 11 - Skip this parameter and continue processing but
1931 * report the unrecognized parameter in an
1932 * 'Unrecognized Parameter' ERROR chunk.
1933 *
1934 * Return value:
1935 * SCTP_IERROR_NO_ERROR - continue with the chunk
1936 * SCTP_IERROR_ERROR - stop and report an error.
1937 * SCTP_IERROR_NOMEME - out of memory.
1938 */
1939 static sctp_ierror_t sctp_process_unk_param(const struct sctp_association *asoc,
1940 union sctp_params param,
1941 struct sctp_chunk *chunk,
1942 struct sctp_chunk **errp)
1943 {
1944 int retval = SCTP_IERROR_NO_ERROR;
1945
1946 switch (param.p->type & SCTP_PARAM_ACTION_MASK) {
1947 case SCTP_PARAM_ACTION_DISCARD:
1948 retval = SCTP_IERROR_ERROR;
1949 break;
1950 case SCTP_PARAM_ACTION_SKIP:
1951 break;
1952 case SCTP_PARAM_ACTION_DISCARD_ERR:
1953 retval = SCTP_IERROR_ERROR;
1954 /* Fall through */
1955 case SCTP_PARAM_ACTION_SKIP_ERR:
1956 /* Make an ERROR chunk, preparing enough room for
1957 * returning multiple unknown parameters.
1958 */
1959 if (NULL == *errp)
1960 *errp = sctp_make_op_error_space(asoc, chunk,
1961 ntohs(chunk->chunk_hdr->length));
1962
1963 if (*errp) {
1964 sctp_init_cause(*errp, SCTP_ERROR_UNKNOWN_PARAM,
1965 WORD_ROUND(ntohs(param.p->length)));
1966 sctp_addto_chunk(*errp,
1967 WORD_ROUND(ntohs(param.p->length)),
1968 param.v);
1969 } else {
1970 /* If there is no memory for generating the ERROR
1971 * report as specified, an ABORT will be triggered
1972 * to the peer and the association won't be
1973 * established.
1974 */
1975 retval = SCTP_IERROR_NOMEM;
1976 }
1977 break;
1978 default:
1979 break;
1980 }
1981
1982 return retval;
1983 }
1984
1985 /* Verify variable length parameters
1986 * Return values:
1987 * SCTP_IERROR_ABORT - trigger an ABORT
1988 * SCTP_IERROR_NOMEM - out of memory (abort)
1989 * SCTP_IERROR_ERROR - stop processing, trigger an ERROR
1990 * SCTP_IERROR_NO_ERROR - continue with the chunk
1991 */
1992 static sctp_ierror_t sctp_verify_param(const struct sctp_association *asoc,
1993 union sctp_params param,
1994 sctp_cid_t cid,
1995 struct sctp_chunk *chunk,
1996 struct sctp_chunk **err_chunk)
1997 {
1998 struct sctp_hmac_algo_param *hmacs;
1999 int retval = SCTP_IERROR_NO_ERROR;
2000 __u16 n_elt, id = 0;
2001 int i;
2002
2003 /* FIXME - This routine is not looking at each parameter per the
2004 * chunk type, i.e., unrecognized parameters should be further
2005 * identified based on the chunk id.
2006 */
2007
2008 switch (param.p->type) {
2009 case SCTP_PARAM_IPV4_ADDRESS:
2010 case SCTP_PARAM_IPV6_ADDRESS:
2011 case SCTP_PARAM_COOKIE_PRESERVATIVE:
2012 case SCTP_PARAM_SUPPORTED_ADDRESS_TYPES:
2013 case SCTP_PARAM_STATE_COOKIE:
2014 case SCTP_PARAM_HEARTBEAT_INFO:
2015 case SCTP_PARAM_UNRECOGNIZED_PARAMETERS:
2016 case SCTP_PARAM_ECN_CAPABLE:
2017 case SCTP_PARAM_ADAPTATION_LAYER_IND:
2018 break;
2019
2020 case SCTP_PARAM_SUPPORTED_EXT:
2021 if (!sctp_verify_ext_param(param))
2022 return SCTP_IERROR_ABORT;
2023 break;
2024
2025 case SCTP_PARAM_SET_PRIMARY:
2026 if (sctp_addip_enable)
2027 break;
2028 goto fallthrough;
2029
2030 case SCTP_PARAM_HOST_NAME_ADDRESS:
2031 /* Tell the peer, we won't support this param. */
2032 sctp_process_hn_param(asoc, param, chunk, err_chunk);
2033 retval = SCTP_IERROR_ABORT;
2034 break;
2035
2036 case SCTP_PARAM_FWD_TSN_SUPPORT:
2037 if (sctp_prsctp_enable)
2038 break;
2039 goto fallthrough;
2040
2041 case SCTP_PARAM_RANDOM:
2042 if (!sctp_auth_enable)
2043 goto fallthrough;
2044
2045 /* SCTP-AUTH: Secion 6.1
2046 * If the random number is not 32 byte long the association
2047 * MUST be aborted. The ABORT chunk SHOULD contain the error
2048 * cause 'Protocol Violation'.
2049 */
2050 if (SCTP_AUTH_RANDOM_LENGTH !=
2051 ntohs(param.p->length) - sizeof(sctp_paramhdr_t)) {
2052 sctp_process_inv_paramlength(asoc, param.p,
2053 chunk, err_chunk);
2054 retval = SCTP_IERROR_ABORT;
2055 }
2056 break;
2057
2058 case SCTP_PARAM_CHUNKS:
2059 if (!sctp_auth_enable)
2060 goto fallthrough;
2061
2062 /* SCTP-AUTH: Section 3.2
2063 * The CHUNKS parameter MUST be included once in the INIT or
2064 * INIT-ACK chunk if the sender wants to receive authenticated
2065 * chunks. Its maximum length is 260 bytes.
2066 */
2067 if (260 < ntohs(param.p->length)) {
2068 sctp_process_inv_paramlength(asoc, param.p,
2069 chunk, err_chunk);
2070 retval = SCTP_IERROR_ABORT;
2071 }
2072 break;
2073
2074 case SCTP_PARAM_HMAC_ALGO:
2075 if (!sctp_auth_enable)
2076 goto fallthrough;
2077
2078 hmacs = (struct sctp_hmac_algo_param *)param.p;
2079 n_elt = (ntohs(param.p->length) - sizeof(sctp_paramhdr_t)) >> 1;
2080
2081 /* SCTP-AUTH: Section 6.1
2082 * The HMAC algorithm based on SHA-1 MUST be supported and
2083 * included in the HMAC-ALGO parameter.
2084 */
2085 for (i = 0; i < n_elt; i++) {
2086 id = ntohs(hmacs->hmac_ids[i]);
2087
2088 if (id == SCTP_AUTH_HMAC_ID_SHA1)
2089 break;
2090 }
2091
2092 if (id != SCTP_AUTH_HMAC_ID_SHA1) {
2093 sctp_process_inv_paramlength(asoc, param.p, chunk,
2094 err_chunk);
2095 retval = SCTP_IERROR_ABORT;
2096 }
2097 break;
2098 fallthrough:
2099 default:
2100 SCTP_DEBUG_PRINTK("Unrecognized param: %d for chunk %d.\n",
2101 ntohs(param.p->type), cid);
2102 retval = sctp_process_unk_param(asoc, param, chunk, err_chunk);
2103 break;
2104 }
2105 return retval;
2106 }
2107
2108 /* Verify the INIT packet before we process it. */
2109 int sctp_verify_init(const struct sctp_association *asoc,
2110 sctp_cid_t cid,
2111 sctp_init_chunk_t *peer_init,
2112 struct sctp_chunk *chunk,
2113 struct sctp_chunk **errp)
2114 {
2115 union sctp_params param;
2116 int has_cookie = 0;
2117 int result;
2118
2119 /* Verify stream values are non-zero. */
2120 if ((0 == peer_init->init_hdr.num_outbound_streams) ||
2121 (0 == peer_init->init_hdr.num_inbound_streams) ||
2122 (0 == peer_init->init_hdr.init_tag) ||
2123 (SCTP_DEFAULT_MINWINDOW > ntohl(peer_init->init_hdr.a_rwnd))) {
2124
2125 return sctp_process_inv_mandatory(asoc, chunk, errp);
2126 }
2127
2128 /* Check for missing mandatory parameters. */
2129 sctp_walk_params(param, peer_init, init_hdr.params) {
2130
2131 if (SCTP_PARAM_STATE_COOKIE == param.p->type)
2132 has_cookie = 1;
2133
2134 } /* for (loop through all parameters) */
2135
2136 /* There is a possibility that a parameter length was bad and
2137 * in that case we would have stoped walking the parameters.
2138 * The current param.p would point at the bad one.
2139 * Current consensus on the mailing list is to generate a PROTOCOL
2140 * VIOLATION error. We build the ERROR chunk here and let the normal
2141 * error handling code build and send the packet.
2142 */
2143 if (param.v != (void*)chunk->chunk_end)
2144 return sctp_process_inv_paramlength(asoc, param.p, chunk, errp);
2145
2146 /* The only missing mandatory param possible today is
2147 * the state cookie for an INIT-ACK chunk.
2148 */
2149 if ((SCTP_CID_INIT_ACK == cid) && !has_cookie)
2150 return sctp_process_missing_param(asoc, SCTP_PARAM_STATE_COOKIE,
2151 chunk, errp);
2152
2153 /* Verify all the variable length parameters */
2154 sctp_walk_params(param, peer_init, init_hdr.params) {
2155
2156 result = sctp_verify_param(asoc, param, cid, chunk, errp);
2157 switch (result) {
2158 case SCTP_IERROR_ABORT:
2159 case SCTP_IERROR_NOMEM:
2160 return 0;
2161 case SCTP_IERROR_ERROR:
2162 return 1;
2163 case SCTP_IERROR_NO_ERROR:
2164 default:
2165 break;
2166 }
2167
2168 } /* for (loop through all parameters) */
2169
2170 return 1;
2171 }
2172
2173 /* Unpack the parameters in an INIT packet into an association.
2174 * Returns 0 on failure, else success.
2175 * FIXME: This is an association method.
2176 */
2177 int sctp_process_init(struct sctp_association *asoc, sctp_cid_t cid,
2178 const union sctp_addr *peer_addr,
2179 sctp_init_chunk_t *peer_init, gfp_t gfp)
2180 {
2181 union sctp_params param;
2182 struct sctp_transport *transport;
2183 struct list_head *pos, *temp;
2184 char *cookie;
2185
2186 /* We must include the address that the INIT packet came from.
2187 * This is the only address that matters for an INIT packet.
2188 * When processing a COOKIE ECHO, we retrieve the from address
2189 * of the INIT from the cookie.
2190 */
2191
2192 /* This implementation defaults to making the first transport
2193 * added as the primary transport. The source address seems to
2194 * be a a better choice than any of the embedded addresses.
2195 */
2196 if (peer_addr) {
2197 if(!sctp_assoc_add_peer(asoc, peer_addr, gfp, SCTP_ACTIVE))
2198 goto nomem;
2199 }
2200
2201 /* Process the initialization parameters. */
2202 sctp_walk_params(param, peer_init, init_hdr.params) {
2203
2204 if (!sctp_process_param(asoc, param, peer_addr, gfp))
2205 goto clean_up;
2206 }
2207
2208 /* AUTH: After processing the parameters, make sure that we
2209 * have all the required info to potentially do authentications.
2210 */
2211 if (asoc->peer.auth_capable && (!asoc->peer.peer_random ||
2212 !asoc->peer.peer_hmacs))
2213 asoc->peer.auth_capable = 0;
2214
2215 /* In a non-backward compatible mode, if the peer claims
2216 * support for ADD-IP but not AUTH, the ADD-IP spec states
2217 * that we MUST ABORT the association. Section 6. The section
2218 * also give us an option to silently ignore the packet, which
2219 * is what we'll do here.
2220 */
2221 if (!sctp_addip_noauth &&
2222 (asoc->peer.asconf_capable && !asoc->peer.auth_capable)) {
2223 asoc->peer.addip_disabled_mask |= (SCTP_PARAM_ADD_IP |
2224 SCTP_PARAM_DEL_IP |
2225 SCTP_PARAM_SET_PRIMARY);
2226 asoc->peer.asconf_capable = 0;
2227 goto clean_up;
2228 }
2229
2230 /* Walk list of transports, removing transports in the UNKNOWN state. */
2231 list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
2232 transport = list_entry(pos, struct sctp_transport, transports);
2233 if (transport->state == SCTP_UNKNOWN) {
2234 sctp_assoc_rm_peer(asoc, transport);
2235 }
2236 }
2237
2238 /* The fixed INIT headers are always in network byte
2239 * order.
2240 */
2241 asoc->peer.i.init_tag =
2242 ntohl(peer_init->init_hdr.init_tag);
2243 asoc->peer.i.a_rwnd =
2244 ntohl(peer_init->init_hdr.a_rwnd);
2245 asoc->peer.i.num_outbound_streams =
2246 ntohs(peer_init->init_hdr.num_outbound_streams);
2247 asoc->peer.i.num_inbound_streams =
2248 ntohs(peer_init->init_hdr.num_inbound_streams);
2249 asoc->peer.i.initial_tsn =
2250 ntohl(peer_init->init_hdr.initial_tsn);
2251
2252 /* Apply the upper bounds for output streams based on peer's
2253 * number of inbound streams.
2254 */
2255 if (asoc->c.sinit_num_ostreams >
2256 ntohs(peer_init->init_hdr.num_inbound_streams)) {
2257 asoc->c.sinit_num_ostreams =
2258 ntohs(peer_init->init_hdr.num_inbound_streams);
2259 }
2260
2261 if (asoc->c.sinit_max_instreams >
2262 ntohs(peer_init->init_hdr.num_outbound_streams)) {
2263 asoc->c.sinit_max_instreams =
2264 ntohs(peer_init->init_hdr.num_outbound_streams);
2265 }
2266
2267 /* Copy Initiation tag from INIT to VT_peer in cookie. */
2268 asoc->c.peer_vtag = asoc->peer.i.init_tag;
2269
2270 /* Peer Rwnd : Current calculated value of the peer's rwnd. */
2271 asoc->peer.rwnd = asoc->peer.i.a_rwnd;
2272
2273 /* Copy cookie in case we need to resend COOKIE-ECHO. */
2274 cookie = asoc->peer.cookie;
2275 if (cookie) {
2276 asoc->peer.cookie = kmemdup(cookie, asoc->peer.cookie_len, gfp);
2277 if (!asoc->peer.cookie)
2278 goto clean_up;
2279 }
2280
2281 /* RFC 2960 7.2.1 The initial value of ssthresh MAY be arbitrarily
2282 * high (for example, implementations MAY use the size of the receiver
2283 * advertised window).
2284 */
2285 list_for_each_entry(transport, &asoc->peer.transport_addr_list,
2286 transports) {
2287 transport->ssthresh = asoc->peer.i.a_rwnd;
2288 }
2289
2290 /* Set up the TSN tracking pieces. */
2291 sctp_tsnmap_init(&asoc->peer.tsn_map, SCTP_TSN_MAP_SIZE,
2292 asoc->peer.i.initial_tsn);
2293
2294 /* RFC 2960 6.5 Stream Identifier and Stream Sequence Number
2295 *
2296 * The stream sequence number in all the streams shall start
2297 * from 0 when the association is established. Also, when the
2298 * stream sequence number reaches the value 65535 the next
2299 * stream sequence number shall be set to 0.
2300 */
2301
2302 /* Allocate storage for the negotiated streams if it is not a temporary
2303 * association.
2304 */
2305 if (!asoc->temp) {
2306 int error;
2307
2308 asoc->ssnmap = sctp_ssnmap_new(asoc->c.sinit_max_instreams,
2309 asoc->c.sinit_num_ostreams, gfp);
2310 if (!asoc->ssnmap)
2311 goto clean_up;
2312
2313 error = sctp_assoc_set_id(asoc, gfp);
2314 if (error)
2315 goto clean_up;
2316 }
2317
2318 /* ADDIP Section 4.1 ASCONF Chunk Procedures
2319 *
2320 * When an endpoint has an ASCONF signaled change to be sent to the
2321 * remote endpoint it should do the following:
2322 * ...
2323 * A2) A serial number should be assigned to the Chunk. The serial
2324 * number should be a monotonically increasing number. All serial
2325 * numbers are defined to be initialized at the start of the
2326 * association to the same value as the Initial TSN.
2327 */
2328 asoc->peer.addip_serial = asoc->peer.i.initial_tsn - 1;
2329 return 1;
2330
2331 clean_up:
2332 /* Release the transport structures. */
2333 list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
2334 transport = list_entry(pos, struct sctp_transport, transports);
2335 if (transport->state != SCTP_ACTIVE)
2336 sctp_assoc_rm_peer(asoc, transport);
2337 }
2338
2339 nomem:
2340 return 0;
2341 }
2342
2343
2344 /* Update asoc with the option described in param.
2345 *
2346 * RFC2960 3.3.2.1 Optional/Variable Length Parameters in INIT
2347 *
2348 * asoc is the association to update.
2349 * param is the variable length parameter to use for update.
2350 * cid tells us if this is an INIT, INIT ACK or COOKIE ECHO.
2351 * If the current packet is an INIT we want to minimize the amount of
2352 * work we do. In particular, we should not build transport
2353 * structures for the addresses.
2354 */
2355 static int sctp_process_param(struct sctp_association *asoc,
2356 union sctp_params param,
2357 const union sctp_addr *peer_addr,
2358 gfp_t gfp)
2359 {
2360 union sctp_addr addr;
2361 int i;
2362 __u16 sat;
2363 int retval = 1;
2364 sctp_scope_t scope;
2365 time_t stale;
2366 struct sctp_af *af;
2367 union sctp_addr_param *addr_param;
2368 struct sctp_transport *t;
2369
2370 /* We maintain all INIT parameters in network byte order all the
2371 * time. This allows us to not worry about whether the parameters
2372 * came from a fresh INIT, and INIT ACK, or were stored in a cookie.
2373 */
2374 switch (param.p->type) {
2375 case SCTP_PARAM_IPV6_ADDRESS:
2376 if (PF_INET6 != asoc->base.sk->sk_family)
2377 break;
2378 goto do_addr_param;
2379
2380 case SCTP_PARAM_IPV4_ADDRESS:
2381 /* v4 addresses are not allowed on v6-only socket */
2382 if (ipv6_only_sock(asoc->base.sk))
2383 break;
2384 do_addr_param:
2385 af = sctp_get_af_specific(param_type2af(param.p->type));
2386 af->from_addr_param(&addr, param.addr, htons(asoc->peer.port), 0);
2387 scope = sctp_scope(peer_addr);
2388 if (sctp_in_scope(&addr, scope))
2389 if (!sctp_assoc_add_peer(asoc, &addr, gfp, SCTP_UNCONFIRMED))
2390 return 0;
2391 break;
2392
2393 case SCTP_PARAM_COOKIE_PRESERVATIVE:
2394 if (!sctp_cookie_preserve_enable)
2395 break;
2396
2397 stale = ntohl(param.life->lifespan_increment);
2398
2399 /* Suggested Cookie Life span increment's unit is msec,
2400 * (1/1000sec).
2401 */
2402 asoc->cookie_life.tv_sec += stale / 1000;
2403 asoc->cookie_life.tv_usec += (stale % 1000) * 1000;
2404 break;
2405
2406 case SCTP_PARAM_HOST_NAME_ADDRESS:
2407 SCTP_DEBUG_PRINTK("unimplemented SCTP_HOST_NAME_ADDRESS\n");
2408 break;
2409
2410 case SCTP_PARAM_SUPPORTED_ADDRESS_TYPES:
2411 /* Turn off the default values first so we'll know which
2412 * ones are really set by the peer.
2413 */
2414 asoc->peer.ipv4_address = 0;
2415 asoc->peer.ipv6_address = 0;
2416
2417 /* Assume that peer supports the address family
2418 * by which it sends a packet.
2419 */
2420 if (peer_addr->sa.sa_family == AF_INET6)
2421 asoc->peer.ipv6_address = 1;
2422 else if (peer_addr->sa.sa_family == AF_INET)
2423 asoc->peer.ipv4_address = 1;
2424
2425 /* Cycle through address types; avoid divide by 0. */
2426 sat = ntohs(param.p->length) - sizeof(sctp_paramhdr_t);
2427 if (sat)
2428 sat /= sizeof(__u16);
2429
2430 for (i = 0; i < sat; ++i) {
2431 switch (param.sat->types[i]) {
2432 case SCTP_PARAM_IPV4_ADDRESS:
2433 asoc->peer.ipv4_address = 1;
2434 break;
2435
2436 case SCTP_PARAM_IPV6_ADDRESS:
2437 if (PF_INET6 == asoc->base.sk->sk_family)
2438 asoc->peer.ipv6_address = 1;
2439 break;
2440
2441 case SCTP_PARAM_HOST_NAME_ADDRESS:
2442 asoc->peer.hostname_address = 1;
2443 break;
2444
2445 default: /* Just ignore anything else. */
2446 break;
2447 }
2448 }
2449 break;
2450
2451 case SCTP_PARAM_STATE_COOKIE:
2452 asoc->peer.cookie_len =
2453 ntohs(param.p->length) - sizeof(sctp_paramhdr_t);
2454 asoc->peer.cookie = param.cookie->body;
2455 break;
2456
2457 case SCTP_PARAM_HEARTBEAT_INFO:
2458 /* Would be odd to receive, but it causes no problems. */
2459 break;
2460
2461 case SCTP_PARAM_UNRECOGNIZED_PARAMETERS:
2462 /* Rejected during verify stage. */
2463 break;
2464
2465 case SCTP_PARAM_ECN_CAPABLE:
2466 asoc->peer.ecn_capable = 1;
2467 break;
2468
2469 case SCTP_PARAM_ADAPTATION_LAYER_IND:
2470 asoc->peer.adaptation_ind = param.aind->adaptation_ind;
2471 break;
2472
2473 case SCTP_PARAM_SET_PRIMARY:
2474 if (!sctp_addip_enable)
2475 goto fall_through;
2476
2477 addr_param = param.v + sizeof(sctp_addip_param_t);
2478
2479 af = sctp_get_af_specific(param_type2af(param.p->type));
2480 af->from_addr_param(&addr, addr_param,
2481 htons(asoc->peer.port), 0);
2482
2483 /* if the address is invalid, we can't process it.
2484 * XXX: see spec for what to do.
2485 */
2486 if (!af->addr_valid(&addr, NULL, NULL))
2487 break;
2488
2489 t = sctp_assoc_lookup_paddr(asoc, &addr);
2490 if (!t)
2491 break;
2492
2493 sctp_assoc_set_primary(asoc, t);
2494 break;
2495
2496 case SCTP_PARAM_SUPPORTED_EXT:
2497 sctp_process_ext_param(asoc, param);
2498 break;
2499
2500 case SCTP_PARAM_FWD_TSN_SUPPORT:
2501 if (sctp_prsctp_enable) {
2502 asoc->peer.prsctp_capable = 1;
2503 break;
2504 }
2505 /* Fall Through */
2506 goto fall_through;
2507
2508 case SCTP_PARAM_RANDOM:
2509 if (!sctp_auth_enable)
2510 goto fall_through;
2511
2512 /* Save peer's random parameter */
2513 asoc->peer.peer_random = kmemdup(param.p,
2514 ntohs(param.p->length), gfp);
2515 if (!asoc->peer.peer_random) {
2516 retval = 0;
2517 break;
2518 }
2519 break;
2520
2521 case SCTP_PARAM_HMAC_ALGO:
2522 if (!sctp_auth_enable)
2523 goto fall_through;
2524
2525 /* Save peer's HMAC list */
2526 asoc->peer.peer_hmacs = kmemdup(param.p,
2527 ntohs(param.p->length), gfp);
2528 if (!asoc->peer.peer_hmacs) {
2529 retval = 0;
2530 break;
2531 }
2532
2533 /* Set the default HMAC the peer requested*/
2534 sctp_auth_asoc_set_default_hmac(asoc, param.hmac_algo);
2535 break;
2536
2537 case SCTP_PARAM_CHUNKS:
2538 if (!sctp_auth_enable)
2539 goto fall_through;
2540
2541 asoc->peer.peer_chunks = kmemdup(param.p,
2542 ntohs(param.p->length), gfp);
2543 if (!asoc->peer.peer_chunks)
2544 retval = 0;
2545 break;
2546 fall_through:
2547 default:
2548 /* Any unrecognized parameters should have been caught
2549 * and handled by sctp_verify_param() which should be
2550 * called prior to this routine. Simply log the error
2551 * here.
2552 */
2553 SCTP_DEBUG_PRINTK("Ignoring param: %d for association %p.\n",
2554 ntohs(param.p->type), asoc);
2555 break;
2556 }
2557
2558 return retval;
2559 }
2560
2561 /* Select a new verification tag. */
2562 __u32 sctp_generate_tag(const struct sctp_endpoint *ep)
2563 {
2564 /* I believe that this random number generator complies with RFC1750.
2565 * A tag of 0 is reserved for special cases (e.g. INIT).
2566 */
2567 __u32 x;
2568
2569 do {
2570 get_random_bytes(&x, sizeof(__u32));
2571 } while (x == 0);
2572
2573 return x;
2574 }
2575
2576 /* Select an initial TSN to send during startup. */
2577 __u32 sctp_generate_tsn(const struct sctp_endpoint *ep)
2578 {
2579 __u32 retval;
2580
2581 get_random_bytes(&retval, sizeof(__u32));
2582 return retval;
2583 }
2584
2585 /*
2586 * ADDIP 3.1.1 Address Configuration Change Chunk (ASCONF)
2587 * 0 1 2 3
2588 * 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
2589 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2590 * | Type = 0xC1 | Chunk Flags | Chunk Length |
2591 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2592 * | Serial Number |
2593 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2594 * | Address Parameter |
2595 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2596 * | ASCONF Parameter #1 |
2597 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2598 * \ \
2599 * / .... /
2600 * \ \
2601 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2602 * | ASCONF Parameter #N |
2603 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2604 *
2605 * Address Parameter and other parameter will not be wrapped in this function
2606 */
2607 static struct sctp_chunk *sctp_make_asconf(struct sctp_association *asoc,
2608 union sctp_addr *addr,
2609 int vparam_len)
2610 {
2611 sctp_addiphdr_t asconf;
2612 struct sctp_chunk *retval;
2613 int length = sizeof(asconf) + vparam_len;
2614 union sctp_addr_param addrparam;
2615 int addrlen;
2616 struct sctp_af *af = sctp_get_af_specific(addr->v4.sin_family);
2617
2618 addrlen = af->to_addr_param(addr, &addrparam);
2619 if (!addrlen)
2620 return NULL;
2621 length += addrlen;
2622
2623 /* Create the chunk. */
2624 retval = sctp_make_chunk(asoc, SCTP_CID_ASCONF, 0, length);
2625 if (!retval)
2626 return NULL;
2627
2628 asconf.serial = htonl(asoc->addip_serial++);
2629
2630 retval->subh.addip_hdr =
2631 sctp_addto_chunk(retval, sizeof(asconf), &asconf);
2632 retval->param_hdr.v =
2633 sctp_addto_chunk(retval, addrlen, &addrparam);
2634
2635 return retval;
2636 }
2637
2638 /* ADDIP
2639 * 3.2.1 Add IP Address
2640 * 0 1 2 3
2641 * 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
2642 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2643 * | Type = 0xC001 | Length = Variable |
2644 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2645 * | ASCONF-Request Correlation ID |
2646 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2647 * | Address Parameter |
2648 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2649 *
2650 * 3.2.2 Delete IP Address
2651 * 0 1 2 3
2652 * 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
2653 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2654 * | Type = 0xC002 | Length = Variable |
2655 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2656 * | ASCONF-Request Correlation ID |
2657 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2658 * | Address Parameter |
2659 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2660 *
2661 */
2662 struct sctp_chunk *sctp_make_asconf_update_ip(struct sctp_association *asoc,
2663 union sctp_addr *laddr,
2664 struct sockaddr *addrs,
2665 int addrcnt,
2666 __be16 flags)
2667 {
2668 sctp_addip_param_t param;
2669 struct sctp_chunk *retval;
2670 union sctp_addr_param addr_param;
2671 union sctp_addr *addr;
2672 void *addr_buf;
2673 struct sctp_af *af;
2674 int paramlen = sizeof(param);
2675 int addr_param_len = 0;
2676 int totallen = 0;
2677 int i;
2678
2679 /* Get total length of all the address parameters. */
2680 addr_buf = addrs;
2681 for (i = 0; i < addrcnt; i++) {
2682 addr = (union sctp_addr *)addr_buf;
2683 af = sctp_get_af_specific(addr->v4.sin_family);
2684 addr_param_len = af->to_addr_param(addr, &addr_param);
2685
2686 totallen += paramlen;
2687 totallen += addr_param_len;
2688
2689 addr_buf += af->sockaddr_len;
2690 }
2691
2692 /* Create an asconf chunk with the required length. */
2693 retval = sctp_make_asconf(asoc, laddr, totallen);
2694 if (!retval)
2695 return NULL;
2696
2697 /* Add the address parameters to the asconf chunk. */
2698 addr_buf = addrs;
2699 for (i = 0; i < addrcnt; i++) {
2700 addr = (union sctp_addr *)addr_buf;
2701 af = sctp_get_af_specific(addr->v4.sin_family);
2702 addr_param_len = af->to_addr_param(addr, &addr_param);
2703 param.param_hdr.type = flags;
2704 param.param_hdr.length = htons(paramlen + addr_param_len);
2705 param.crr_id = i;
2706
2707 sctp_addto_chunk(retval, paramlen, &param);
2708 sctp_addto_chunk(retval, addr_param_len, &addr_param);
2709
2710 addr_buf += af->sockaddr_len;
2711 }
2712 return retval;
2713 }
2714
2715 /* ADDIP
2716 * 3.2.4 Set Primary IP Address
2717 * 0 1 2 3
2718 * 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
2719 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2720 * | Type =0xC004 | Length = Variable |
2721 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2722 * | ASCONF-Request Correlation ID |
2723 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2724 * | Address Parameter |
2725 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2726 *
2727 * Create an ASCONF chunk with Set Primary IP address parameter.
2728 */
2729 struct sctp_chunk *sctp_make_asconf_set_prim(struct sctp_association *asoc,
2730 union sctp_addr *addr)
2731 {
2732 sctp_addip_param_t param;
2733 struct sctp_chunk *retval;
2734 int len = sizeof(param);
2735 union sctp_addr_param addrparam;
2736 int addrlen;
2737 struct sctp_af *af = sctp_get_af_specific(addr->v4.sin_family);
2738
2739 addrlen = af->to_addr_param(addr, &addrparam);
2740 if (!addrlen)
2741 return NULL;
2742 len += addrlen;
2743
2744 /* Create the chunk and make asconf header. */
2745 retval = sctp_make_asconf(asoc, addr, len);
2746 if (!retval)
2747 return NULL;
2748
2749 param.param_hdr.type = SCTP_PARAM_SET_PRIMARY;
2750 param.param_hdr.length = htons(len);
2751 param.crr_id = 0;
2752
2753 sctp_addto_chunk(retval, sizeof(param), &param);
2754 sctp_addto_chunk(retval, addrlen, &addrparam);
2755
2756 return retval;
2757 }
2758
2759 /* ADDIP 3.1.2 Address Configuration Acknowledgement Chunk (ASCONF-ACK)
2760 * 0 1 2 3
2761 * 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
2762 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2763 * | Type = 0x80 | Chunk Flags | Chunk Length |
2764 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2765 * | Serial Number |
2766 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2767 * | ASCONF Parameter Response#1 |
2768 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2769 * \ \
2770 * / .... /
2771 * \ \
2772 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2773 * | ASCONF Parameter Response#N |
2774 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2775 *
2776 * Create an ASCONF_ACK chunk with enough space for the parameter responses.
2777 */
2778 static struct sctp_chunk *sctp_make_asconf_ack(const struct sctp_association *asoc,
2779 __u32 serial, int vparam_len)
2780 {
2781 sctp_addiphdr_t asconf;
2782 struct sctp_chunk *retval;
2783 int length = sizeof(asconf) + vparam_len;
2784
2785 /* Create the chunk. */
2786 retval = sctp_make_chunk(asoc, SCTP_CID_ASCONF_ACK, 0, length);
2787 if (!retval)
2788 return NULL;
2789
2790 asconf.serial = htonl(serial);
2791
2792 retval->subh.addip_hdr =
2793 sctp_addto_chunk(retval, sizeof(asconf), &asconf);
2794
2795 return retval;
2796 }
2797
2798 /* Add response parameters to an ASCONF_ACK chunk. */
2799 static void sctp_add_asconf_response(struct sctp_chunk *chunk, __be32 crr_id,
2800 __be16 err_code, sctp_addip_param_t *asconf_param)
2801 {
2802 sctp_addip_param_t ack_param;
2803 sctp_errhdr_t err_param;
2804 int asconf_param_len = 0;
2805 int err_param_len = 0;
2806 __be16 response_type;
2807
2808 if (SCTP_ERROR_NO_ERROR == err_code) {
2809 response_type = SCTP_PARAM_SUCCESS_REPORT;
2810 } else {
2811 response_type = SCTP_PARAM_ERR_CAUSE;
2812 err_param_len = sizeof(err_param);
2813 if (asconf_param)
2814 asconf_param_len =
2815 ntohs(asconf_param->param_hdr.length);
2816 }
2817
2818 /* Add Success Indication or Error Cause Indication parameter. */
2819 ack_param.param_hdr.type = response_type;
2820 ack_param.param_hdr.length = htons(sizeof(ack_param) +
2821 err_param_len +
2822 asconf_param_len);
2823 ack_param.crr_id = crr_id;
2824 sctp_addto_chunk(chunk, sizeof(ack_param), &ack_param);
2825
2826 if (SCTP_ERROR_NO_ERROR == err_code)
2827 return;
2828
2829 /* Add Error Cause parameter. */
2830 err_param.cause = err_code;
2831 err_param.length = htons(err_param_len + asconf_param_len);
2832 sctp_addto_chunk(chunk, err_param_len, &err_param);
2833
2834 /* Add the failed TLV copied from ASCONF chunk. */
2835 if (asconf_param)
2836 sctp_addto_chunk(chunk, asconf_param_len, asconf_param);
2837 }
2838
2839 /* Process a asconf parameter. */
2840 static __be16 sctp_process_asconf_param(struct sctp_association *asoc,
2841 struct sctp_chunk *asconf,
2842 sctp_addip_param_t *asconf_param)
2843 {
2844 struct sctp_transport *peer;
2845 struct sctp_af *af;
2846 union sctp_addr addr;
2847 union sctp_addr_param *addr_param;
2848
2849 addr_param = (union sctp_addr_param *)
2850 ((void *)asconf_param + sizeof(sctp_addip_param_t));
2851
2852 switch (addr_param->v4.param_hdr.type) {
2853 case SCTP_PARAM_IPV6_ADDRESS:
2854 if (!asoc->peer.ipv6_address)
2855 return SCTP_ERROR_INV_PARAM;
2856 break;
2857 case SCTP_PARAM_IPV4_ADDRESS:
2858 if (!asoc->peer.ipv4_address)
2859 return SCTP_ERROR_INV_PARAM;
2860 break;
2861 default:
2862 return SCTP_ERROR_INV_PARAM;
2863 }
2864
2865 af = sctp_get_af_specific(param_type2af(addr_param->v4.param_hdr.type));
2866 if (unlikely(!af))
2867 return SCTP_ERROR_INV_PARAM;
2868
2869 af->from_addr_param(&addr, addr_param, htons(asoc->peer.port), 0);
2870
2871 /* ADDIP 4.2.1 This parameter MUST NOT contain a broadcast
2872 * or multicast address.
2873 * (note: wildcard is permitted and requires special handling so
2874 * make sure we check for that)
2875 */
2876 if (!af->is_any(&addr) && !af->addr_valid(&addr, NULL, asconf->skb))
2877 return SCTP_ERROR_INV_PARAM;
2878
2879 switch (asconf_param->param_hdr.type) {
2880 case SCTP_PARAM_ADD_IP:
2881 /* Section 4.2.1:
2882 * If the address 0.0.0.0 or ::0 is provided, the source
2883 * address of the packet MUST be added.
2884 */
2885 if (af->is_any(&addr))
2886 memcpy(&addr, &asconf->source, sizeof(addr));
2887
2888 /* ADDIP 4.3 D9) If an endpoint receives an ADD IP address
2889 * request and does not have the local resources to add this
2890 * new address to the association, it MUST return an Error
2891 * Cause TLV set to the new error code 'Operation Refused
2892 * Due to Resource Shortage'.
2893 */
2894
2895 peer = sctp_assoc_add_peer(asoc, &addr, GFP_ATOMIC, SCTP_UNCONFIRMED);
2896 if (!peer)
2897 return SCTP_ERROR_RSRC_LOW;
2898
2899 /* Start the heartbeat timer. */
2900 if (!mod_timer(&peer->hb_timer, sctp_transport_timeout(peer)))
2901 sctp_transport_hold(peer);
2902 break;
2903 case SCTP_PARAM_DEL_IP:
2904 /* ADDIP 4.3 D7) If a request is received to delete the
2905 * last remaining IP address of a peer endpoint, the receiver
2906 * MUST send an Error Cause TLV with the error cause set to the
2907 * new error code 'Request to Delete Last Remaining IP Address'.
2908 */
2909 if (asoc->peer.transport_count == 1)
2910 return SCTP_ERROR_DEL_LAST_IP;
2911
2912 /* ADDIP 4.3 D8) If a request is received to delete an IP
2913 * address which is also the source address of the IP packet
2914 * which contained the ASCONF chunk, the receiver MUST reject
2915 * this request. To reject the request the receiver MUST send
2916 * an Error Cause TLV set to the new error code 'Request to
2917 * Delete Source IP Address'
2918 */
2919 if (sctp_cmp_addr_exact(sctp_source(asconf), &addr))
2920 return SCTP_ERROR_DEL_SRC_IP;
2921
2922 /* Section 4.2.2
2923 * If the address 0.0.0.0 or ::0 is provided, all
2924 * addresses of the peer except the source address of the
2925 * packet MUST be deleted.
2926 */
2927 if (af->is_any(&addr)) {
2928 sctp_assoc_set_primary(asoc, asconf->transport);
2929 sctp_assoc_del_nonprimary_peers(asoc,
2930 asconf->transport);
2931 } else
2932 sctp_assoc_del_peer(asoc, &addr);
2933 break;
2934 case SCTP_PARAM_SET_PRIMARY:
2935 /* ADDIP Section 4.2.4
2936 * If the address 0.0.0.0 or ::0 is provided, the receiver
2937 * MAY mark the source address of the packet as its
2938 * primary.
2939 */
2940 if (af->is_any(&addr))
2941 memcpy(&addr.v4, sctp_source(asconf), sizeof(addr));
2942
2943 peer = sctp_assoc_lookup_paddr(asoc, &addr);
2944 if (!peer)
2945 return SCTP_ERROR_INV_PARAM;
2946
2947 sctp_assoc_set_primary(asoc, peer);
2948 break;
2949 default:
2950 return SCTP_ERROR_INV_PARAM;
2951 break;
2952 }
2953
2954 return SCTP_ERROR_NO_ERROR;
2955 }
2956
2957 /* Verify the ASCONF packet before we process it. */
2958 int sctp_verify_asconf(const struct sctp_association *asoc,
2959 struct sctp_paramhdr *param_hdr, void *chunk_end,
2960 struct sctp_paramhdr **errp) {
2961 sctp_addip_param_t *asconf_param;
2962 union sctp_params param;
2963 int length, plen;
2964
2965 param.v = (sctp_paramhdr_t *) param_hdr;
2966 while (param.v <= chunk_end - sizeof(sctp_paramhdr_t)) {
2967 length = ntohs(param.p->length);
2968 *errp = param.p;
2969
2970 if (param.v > chunk_end - length ||
2971 length < sizeof(sctp_paramhdr_t))
2972 return 0;
2973
2974 switch (param.p->type) {
2975 case SCTP_PARAM_ADD_IP:
2976 case SCTP_PARAM_DEL_IP:
2977 case SCTP_PARAM_SET_PRIMARY:
2978 asconf_param = (sctp_addip_param_t *)param.v;
2979 plen = ntohs(asconf_param->param_hdr.length);
2980 if (plen < sizeof(sctp_addip_param_t) +
2981 sizeof(sctp_paramhdr_t))
2982 return 0;
2983 break;
2984 case SCTP_PARAM_SUCCESS_REPORT:
2985 case SCTP_PARAM_ADAPTATION_LAYER_IND:
2986 if (length != sizeof(sctp_addip_param_t))
2987 return 0;
2988
2989 break;
2990 default:
2991 break;
2992 }
2993
2994 param.v += WORD_ROUND(length);
2995 }
2996
2997 if (param.v != chunk_end)
2998 return 0;
2999
3000 return 1;
3001 }
3002
3003 /* Process an incoming ASCONF chunk with the next expected serial no. and
3004 * return an ASCONF_ACK chunk to be sent in response.
3005 */
3006 struct sctp_chunk *sctp_process_asconf(struct sctp_association *asoc,
3007 struct sctp_chunk *asconf)
3008 {
3009 sctp_addiphdr_t *hdr;
3010 union sctp_addr_param *addr_param;
3011 sctp_addip_param_t *asconf_param;
3012 struct sctp_chunk *asconf_ack;
3013
3014 __be16 err_code;
3015 int length = 0;
3016 int chunk_len;
3017 __u32 serial;
3018 int all_param_pass = 1;
3019
3020 chunk_len = ntohs(asconf->chunk_hdr->length) - sizeof(sctp_chunkhdr_t);
3021 hdr = (sctp_addiphdr_t *)asconf->skb->data;
3022 serial = ntohl(hdr->serial);
3023
3024 /* Skip the addiphdr and store a pointer to address parameter. */
3025 length = sizeof(sctp_addiphdr_t);
3026 addr_param = (union sctp_addr_param *)(asconf->skb->data + length);
3027 chunk_len -= length;
3028
3029 /* Skip the address parameter and store a pointer to the first
3030 * asconf parameter.
3031 */
3032 length = ntohs(addr_param->v4.param_hdr.length);
3033 asconf_param = (sctp_addip_param_t *)((void *)addr_param + length);
3034 chunk_len -= length;
3035
3036 /* create an ASCONF_ACK chunk.
3037 * Based on the definitions of parameters, we know that the size of
3038 * ASCONF_ACK parameters are less than or equal to the twice of ASCONF
3039 * parameters.
3040 */
3041 asconf_ack = sctp_make_asconf_ack(asoc, serial, chunk_len * 2);
3042 if (!asconf_ack)
3043 goto done;
3044
3045 /* Process the TLVs contained within the ASCONF chunk. */
3046 while (chunk_len > 0) {
3047 err_code = sctp_process_asconf_param(asoc, asconf,
3048 asconf_param);
3049 /* ADDIP 4.1 A7)
3050 * If an error response is received for a TLV parameter,
3051 * all TLVs with no response before the failed TLV are
3052 * considered successful if not reported. All TLVs after
3053 * the failed response are considered unsuccessful unless
3054 * a specific success indication is present for the parameter.
3055 */
3056 if (SCTP_ERROR_NO_ERROR != err_code)
3057 all_param_pass = 0;
3058
3059 if (!all_param_pass)
3060 sctp_add_asconf_response(asconf_ack,
3061 asconf_param->crr_id, err_code,
3062 asconf_param);
3063
3064 /* ADDIP 4.3 D11) When an endpoint receiving an ASCONF to add
3065 * an IP address sends an 'Out of Resource' in its response, it
3066 * MUST also fail any subsequent add or delete requests bundled
3067 * in the ASCONF.
3068 */
3069 if (SCTP_ERROR_RSRC_LOW == err_code)
3070 goto done;
3071
3072 /* Move to the next ASCONF param. */
3073 length = ntohs(asconf_param->param_hdr.length);
3074 asconf_param = (sctp_addip_param_t *)((void *)asconf_param +
3075 length);
3076 chunk_len -= length;
3077 }
3078
3079 done:
3080 asoc->peer.addip_serial++;
3081
3082 /* If we are sending a new ASCONF_ACK hold a reference to it in assoc
3083 * after freeing the reference to old asconf ack if any.
3084 */
3085 if (asconf_ack) {
3086 sctp_chunk_hold(asconf_ack);
3087 list_add_tail(&asconf_ack->transmitted_list,
3088 &asoc->asconf_ack_list);
3089 }
3090
3091 return asconf_ack;
3092 }
3093
3094 /* Process a asconf parameter that is successfully acked. */
3095 static int sctp_asconf_param_success(struct sctp_association *asoc,
3096 sctp_addip_param_t *asconf_param)
3097 {
3098 struct sctp_af *af;
3099 union sctp_addr addr;
3100 struct sctp_bind_addr *bp = &asoc->base.bind_addr;
3101 union sctp_addr_param *addr_param;
3102 struct sctp_transport *transport;
3103 struct sctp_sockaddr_entry *saddr;
3104 int retval = 0;
3105
3106 addr_param = (union sctp_addr_param *)
3107 ((void *)asconf_param + sizeof(sctp_addip_param_t));
3108
3109 /* We have checked the packet before, so we do not check again. */
3110 af = sctp_get_af_specific(param_type2af(addr_param->v4.param_hdr.type));
3111 af->from_addr_param(&addr, addr_param, htons(bp->port), 0);
3112
3113 switch (asconf_param->param_hdr.type) {
3114 case SCTP_PARAM_ADD_IP:
3115 /* This is always done in BH context with a socket lock
3116 * held, so the list can not change.
3117 */
3118 local_bh_disable();
3119 list_for_each_entry(saddr, &bp->address_list, list) {
3120 if (sctp_cmp_addr_exact(&saddr->a, &addr))
3121 saddr->state = SCTP_ADDR_SRC;
3122 }
3123 local_bh_enable();
3124 break;
3125 case SCTP_PARAM_DEL_IP:
3126 local_bh_disable();
3127 retval = sctp_del_bind_addr(bp, &addr);
3128 local_bh_enable();
3129 list_for_each_entry(transport, &asoc->peer.transport_addr_list,
3130 transports) {
3131 dst_release(transport->dst);
3132 sctp_transport_route(transport, NULL,
3133 sctp_sk(asoc->base.sk));
3134 }
3135 break;
3136 default:
3137 break;
3138 }
3139
3140 return retval;
3141 }
3142
3143 /* Get the corresponding ASCONF response error code from the ASCONF_ACK chunk
3144 * for the given asconf parameter. If there is no response for this parameter,
3145 * return the error code based on the third argument 'no_err'.
3146 * ADDIP 4.1
3147 * A7) If an error response is received for a TLV parameter, all TLVs with no
3148 * response before the failed TLV are considered successful if not reported.
3149 * All TLVs after the failed response are considered unsuccessful unless a
3150 * specific success indication is present for the parameter.
3151 */
3152 static __be16 sctp_get_asconf_response(struct sctp_chunk *asconf_ack,
3153 sctp_addip_param_t *asconf_param,
3154 int no_err)
3155 {
3156 sctp_addip_param_t *asconf_ack_param;
3157 sctp_errhdr_t *err_param;
3158 int length;
3159 int asconf_ack_len;
3160 __be16 err_code;
3161
3162 if (no_err)
3163 err_code = SCTP_ERROR_NO_ERROR;
3164 else
3165 err_code = SCTP_ERROR_REQ_REFUSED;
3166
3167 asconf_ack_len = ntohs(asconf_ack->chunk_hdr->length) -
3168 sizeof(sctp_chunkhdr_t);
3169
3170 /* Skip the addiphdr from the asconf_ack chunk and store a pointer to
3171 * the first asconf_ack parameter.
3172 */
3173 length = sizeof(sctp_addiphdr_t);
3174 asconf_ack_param = (sctp_addip_param_t *)(asconf_ack->skb->data +
3175 length);
3176 asconf_ack_len -= length;
3177
3178 while (asconf_ack_len > 0) {
3179 if (asconf_ack_param->crr_id == asconf_param->crr_id) {
3180 switch(asconf_ack_param->param_hdr.type) {
3181 case SCTP_PARAM_SUCCESS_REPORT:
3182 return SCTP_ERROR_NO_ERROR;
3183 case SCTP_PARAM_ERR_CAUSE:
3184 length = sizeof(sctp_addip_param_t);
3185 err_param = (sctp_errhdr_t *)
3186 ((void *)asconf_ack_param + length);
3187 asconf_ack_len -= length;
3188 if (asconf_ack_len > 0)
3189 return err_param->cause;
3190 else
3191 return SCTP_ERROR_INV_PARAM;
3192 break;
3193 default:
3194 return SCTP_ERROR_INV_PARAM;
3195 }
3196 }
3197
3198 length = ntohs(asconf_ack_param->param_hdr.length);
3199 asconf_ack_param = (sctp_addip_param_t *)
3200 ((void *)asconf_ack_param + length);
3201 asconf_ack_len -= length;
3202 }
3203
3204 return err_code;
3205 }
3206
3207 /* Process an incoming ASCONF_ACK chunk against the cached last ASCONF chunk. */
3208 int sctp_process_asconf_ack(struct sctp_association *asoc,
3209 struct sctp_chunk *asconf_ack)
3210 {
3211 struct sctp_chunk *asconf = asoc->addip_last_asconf;
3212 union sctp_addr_param *addr_param;
3213 sctp_addip_param_t *asconf_param;
3214 int length = 0;
3215 int asconf_len = asconf->skb->len;
3216 int all_param_pass = 0;
3217 int no_err = 1;
3218 int retval = 0;
3219 __be16 err_code = SCTP_ERROR_NO_ERROR;
3220
3221 /* Skip the chunkhdr and addiphdr from the last asconf sent and store
3222 * a pointer to address parameter.
3223 */
3224 length = sizeof(sctp_addip_chunk_t);
3225 addr_param = (union sctp_addr_param *)(asconf->skb->data + length);
3226 asconf_len -= length;
3227
3228 /* Skip the address parameter in the last asconf sent and store a
3229 * pointer to the first asconf parameter.
3230 */
3231 length = ntohs(addr_param->v4.param_hdr.length);
3232 asconf_param = (sctp_addip_param_t *)((void *)addr_param + length);
3233 asconf_len -= length;
3234
3235 /* ADDIP 4.1
3236 * A8) If there is no response(s) to specific TLV parameter(s), and no
3237 * failures are indicated, then all request(s) are considered
3238 * successful.
3239 */
3240 if (asconf_ack->skb->len == sizeof(sctp_addiphdr_t))
3241 all_param_pass = 1;
3242
3243 /* Process the TLVs contained in the last sent ASCONF chunk. */
3244 while (asconf_len > 0) {
3245 if (all_param_pass)
3246 err_code = SCTP_ERROR_NO_ERROR;
3247 else {
3248 err_code = sctp_get_asconf_response(asconf_ack,
3249 asconf_param,
3250 no_err);
3251 if (no_err && (SCTP_ERROR_NO_ERROR != err_code))
3252 no_err = 0;
3253 }
3254
3255 switch (err_code) {
3256 case SCTP_ERROR_NO_ERROR:
3257 retval = sctp_asconf_param_success(asoc, asconf_param);
3258 break;
3259
3260 case SCTP_ERROR_RSRC_LOW:
3261 retval = 1;
3262 break;
3263
3264 case SCTP_ERROR_INV_PARAM:
3265 /* Disable sending this type of asconf parameter in
3266 * future.
3267 */
3268 asoc->peer.addip_disabled_mask |=
3269 asconf_param->param_hdr.type;
3270 break;
3271
3272 case SCTP_ERROR_REQ_REFUSED:
3273 case SCTP_ERROR_DEL_LAST_IP:
3274 case SCTP_ERROR_DEL_SRC_IP:
3275 default:
3276 break;
3277 }
3278
3279 /* Skip the processed asconf parameter and move to the next
3280 * one.
3281 */
3282 length = ntohs(asconf_param->param_hdr.length);
3283 asconf_param = (sctp_addip_param_t *)((void *)asconf_param +
3284 length);
3285 asconf_len -= length;
3286 }
3287
3288 /* Free the cached last sent asconf chunk. */
3289 list_del_init(&asconf->transmitted_list);
3290 sctp_chunk_free(asconf);
3291 asoc->addip_last_asconf = NULL;
3292
3293 /* Send the next asconf chunk from the addip chunk queue. */
3294 if (!list_empty(&asoc->addip_chunk_list)) {
3295 struct list_head *entry = asoc->addip_chunk_list.next;
3296 asconf = list_entry(entry, struct sctp_chunk, list);
3297
3298 list_del_init(entry);
3299
3300 /* Hold the chunk until an ASCONF_ACK is received. */
3301 sctp_chunk_hold(asconf);
3302 if (sctp_primitive_ASCONF(asoc, asconf))
3303 sctp_chunk_free(asconf);
3304 else
3305 asoc->addip_last_asconf = asconf;
3306 }
3307
3308 return retval;
3309 }
3310
3311 /* Make a FWD TSN chunk. */
3312 struct sctp_chunk *sctp_make_fwdtsn(const struct sctp_association *asoc,
3313 __u32 new_cum_tsn, size_t nstreams,
3314 struct sctp_fwdtsn_skip *skiplist)
3315 {
3316 struct sctp_chunk *retval = NULL;
3317 struct sctp_fwdtsn_chunk *ftsn_chunk;
3318 struct sctp_fwdtsn_hdr ftsn_hdr;
3319 struct sctp_fwdtsn_skip skip;
3320 size_t hint;
3321 int i;
3322
3323 hint = (nstreams + 1) * sizeof(__u32);
3324
3325 retval = sctp_make_chunk(asoc, SCTP_CID_FWD_TSN, 0, hint);
3326
3327 if (!retval)
3328 return NULL;
3329
3330 ftsn_chunk = (struct sctp_fwdtsn_chunk *)retval->subh.fwdtsn_hdr;
3331
3332 ftsn_hdr.new_cum_tsn = htonl(new_cum_tsn);
3333 retval->subh.fwdtsn_hdr =
3334 sctp_addto_chunk(retval, sizeof(ftsn_hdr), &ftsn_hdr);
3335
3336 for (i = 0; i < nstreams; i++) {
3337 skip.stream = skiplist[i].stream;
3338 skip.ssn = skiplist[i].ssn;
3339 sctp_addto_chunk(retval, sizeof(skip), &skip);
3340 }
3341
3342 return retval;
3343 }
Linus' kernel tree