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net: only use a single page of slop in MAX_SKB_FRAGS
[linux-2.6.git] / net / sctp / sm_make_chunk.c
bloba85eeeb55dd0022e009895c53a6d8593929b7691
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 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
54
55 #include <linux/types.h>
56 #include <linux/kernel.h>
57 #include <linux/ip.h>
58 #include <linux/ipv6.h>
59 #include <linux/net.h>
60 #include <linux/inet.h>
61 #include <linux/scatterlist.h>
62 #include <linux/crypto.h>
63 #include <linux/slab.h>
64 #include <net/sock.h>
65
66 #include <linux/skbuff.h>
67 #include <linux/random.h> /* for get_random_bytes */
68 #include <net/sctp/sctp.h>
69 #include <net/sctp/sm.h>
70
71 SCTP_STATIC
72 struct sctp_chunk *sctp_make_chunk(const struct sctp_association *asoc,
73 __u8 type, __u8 flags, int paylen);
74 static sctp_cookie_param_t *sctp_pack_cookie(const struct sctp_endpoint *ep,
75 const struct sctp_association *asoc,
76 const struct sctp_chunk *init_chunk,
77 int *cookie_len,
78 const __u8 *raw_addrs, int addrs_len);
79 static int sctp_process_param(struct sctp_association *asoc,
80 union sctp_params param,
81 const union sctp_addr *peer_addr,
82 gfp_t gfp);
83 static void *sctp_addto_param(struct sctp_chunk *chunk, int len,
84 const void *data);
85
86 /* What was the inbound interface for this chunk? */
87 int sctp_chunk_iif(const struct sctp_chunk *chunk)
88 {
89 struct sctp_af *af;
90 int iif = 0;
91
92 af = sctp_get_af_specific(ipver2af(ip_hdr(chunk->skb)->version));
93 if (af)
94 iif = af->skb_iif(chunk->skb);
95
96 return iif;
97 }
98
99 /* RFC 2960 3.3.2 Initiation (INIT) (1)
100 *
101 * Note 2: The ECN capable field is reserved for future use of
102 * Explicit Congestion Notification.
103 */
104 static const struct sctp_paramhdr ecap_param = {
105 SCTP_PARAM_ECN_CAPABLE,
106 cpu_to_be16(sizeof(struct sctp_paramhdr)),
107 };
108 static const struct sctp_paramhdr prsctp_param = {
109 SCTP_PARAM_FWD_TSN_SUPPORT,
110 cpu_to_be16(sizeof(struct sctp_paramhdr)),
111 };
112
113 /* A helper to initialize an op error inside a
114 * provided chunk, as most cause codes will be embedded inside an
115 * abort chunk.
116 */
117 void sctp_init_cause(struct sctp_chunk *chunk, __be16 cause_code,
118 size_t paylen)
119 {
120 sctp_errhdr_t err;
121 __u16 len;
122
123 /* Cause code constants are now defined in network order. */
124 err.cause = cause_code;
125 len = sizeof(sctp_errhdr_t) + paylen;
126 err.length = htons(len);
127 chunk->subh.err_hdr = sctp_addto_chunk(chunk, sizeof(sctp_errhdr_t), &err);
128 }
129
130 /* A helper to initialize an op error inside a
131 * provided chunk, as most cause codes will be embedded inside an
132 * abort chunk. Differs from sctp_init_cause in that it won't oops
133 * if there isn't enough space in the op error chunk
134 */
135 int sctp_init_cause_fixed(struct sctp_chunk *chunk, __be16 cause_code,
136 size_t paylen)
137 {
138 sctp_errhdr_t err;
139 __u16 len;
140
141 /* Cause code constants are now defined in network order. */
142 err.cause = cause_code;
143 len = sizeof(sctp_errhdr_t) + paylen;
144 err.length = htons(len);
145
146 if (skb_tailroom(chunk->skb) < len)
147 return -ENOSPC;
148 chunk->subh.err_hdr = sctp_addto_chunk_fixed(chunk,
149 sizeof(sctp_errhdr_t),
150 &err);
151 return 0;
152 }
153 /* 3.3.2 Initiation (INIT) (1)
154 *
155 * This chunk is used to initiate a SCTP association between two
156 * endpoints. The format of the INIT chunk is shown below:
157 *
158 * 0 1 2 3
159 * 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
160 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
161 * | Type = 1 | Chunk Flags | Chunk Length |
162 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
163 * | Initiate Tag |
164 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
165 * | Advertised Receiver Window Credit (a_rwnd) |
166 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
167 * | Number of Outbound Streams | Number of Inbound Streams |
168 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
169 * | Initial TSN |
170 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
171 * \ \
172 * / Optional/Variable-Length Parameters /
173 * \ \
174 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
175 *
176 *
177 * The INIT chunk contains the following parameters. Unless otherwise
178 * noted, each parameter MUST only be included once in the INIT chunk.
179 *
180 * Fixed Parameters Status
181 * ----------------------------------------------
182 * Initiate Tag Mandatory
183 * Advertised Receiver Window Credit Mandatory
184 * Number of Outbound Streams Mandatory
185 * Number of Inbound Streams Mandatory
186 * Initial TSN Mandatory
187 *
188 * Variable Parameters Status Type Value
189 * -------------------------------------------------------------
190 * IPv4 Address (Note 1) Optional 5
191 * IPv6 Address (Note 1) Optional 6
192 * Cookie Preservative Optional 9
193 * Reserved for ECN Capable (Note 2) Optional 32768 (0x8000)
194 * Host Name Address (Note 3) Optional 11
195 * Supported Address Types (Note 4) Optional 12
196 */
197 struct sctp_chunk *sctp_make_init(const struct sctp_association *asoc,
198 const struct sctp_bind_addr *bp,
199 gfp_t gfp, int vparam_len)
200 {
201 sctp_inithdr_t init;
202 union sctp_params addrs;
203 size_t chunksize;
204 struct sctp_chunk *retval = NULL;
205 int num_types, addrs_len = 0;
206 struct sctp_sock *sp;
207 sctp_supported_addrs_param_t sat;
208 __be16 types[2];
209 sctp_adaptation_ind_param_t aiparam;
210 sctp_supported_ext_param_t ext_param;
211 int num_ext = 0;
212 __u8 extensions[3];
213 sctp_paramhdr_t *auth_chunks = NULL,
214 *auth_hmacs = NULL;
215
216 /* RFC 2960 3.3.2 Initiation (INIT) (1)
217 *
218 * Note 1: The INIT chunks can contain multiple addresses that
219 * can be IPv4 and/or IPv6 in any combination.
220 */
221 retval = NULL;
222
223 /* Convert the provided bind address list to raw format. */
224 addrs = sctp_bind_addrs_to_raw(bp, &addrs_len, gfp);
225
226 init.init_tag = htonl(asoc->c.my_vtag);
227 init.a_rwnd = htonl(asoc->rwnd);
228 init.num_outbound_streams = htons(asoc->c.sinit_num_ostreams);
229 init.num_inbound_streams = htons(asoc->c.sinit_max_instreams);
230 init.initial_tsn = htonl(asoc->c.initial_tsn);
231
232 /* How many address types are needed? */
233 sp = sctp_sk(asoc->base.sk);
234 num_types = sp->pf->supported_addrs(sp, types);
235
236 chunksize = sizeof(init) + addrs_len;
237 chunksize += WORD_ROUND(SCTP_SAT_LEN(num_types));
238 chunksize += sizeof(ecap_param);
239
240 if (sctp_prsctp_enable)
241 chunksize += sizeof(prsctp_param);
242
243 /* ADDIP: Section 4.2.7:
244 * An implementation supporting this extension [ADDIP] MUST list
245 * the ASCONF,the ASCONF-ACK, and the AUTH chunks in its INIT and
246 * INIT-ACK parameters.
247 */
248 if (sctp_addip_enable) {
249 extensions[num_ext] = SCTP_CID_ASCONF;
250 extensions[num_ext+1] = SCTP_CID_ASCONF_ACK;
251 num_ext += 2;
252 }
253
254 if (sp->adaptation_ind)
255 chunksize += sizeof(aiparam);
256
257 chunksize += vparam_len;
258
259 /* Account for AUTH related parameters */
260 if (sctp_auth_enable) {
261 /* Add random parameter length*/
262 chunksize += sizeof(asoc->c.auth_random);
263
264 /* Add HMACS parameter length if any were defined */
265 auth_hmacs = (sctp_paramhdr_t *)asoc->c.auth_hmacs;
266 if (auth_hmacs->length)
267 chunksize += WORD_ROUND(ntohs(auth_hmacs->length));
268 else
269 auth_hmacs = NULL;
270
271 /* Add CHUNKS parameter length */
272 auth_chunks = (sctp_paramhdr_t *)asoc->c.auth_chunks;
273 if (auth_chunks->length)
274 chunksize += WORD_ROUND(ntohs(auth_chunks->length));
275 else
276 auth_chunks = NULL;
277
278 extensions[num_ext] = SCTP_CID_AUTH;
279 num_ext += 1;
280 }
281
282 /* If we have any extensions to report, account for that */
283 if (num_ext)
284 chunksize += WORD_ROUND(sizeof(sctp_supported_ext_param_t) +
285 num_ext);
286
287 /* RFC 2960 3.3.2 Initiation (INIT) (1)
288 *
289 * Note 3: An INIT chunk MUST NOT contain more than one Host
290 * Name address parameter. Moreover, the sender of the INIT
291 * MUST NOT combine any other address types with the Host Name
292 * address in the INIT. The receiver of INIT MUST ignore any
293 * other address types if the Host Name address parameter is
294 * present in the received INIT chunk.
295 *
296 * PLEASE DO NOT FIXME [This version does not support Host Name.]
297 */
298
299 retval = sctp_make_chunk(asoc, SCTP_CID_INIT, 0, chunksize);
300 if (!retval)
301 goto nodata;
302
303 retval->subh.init_hdr =
304 sctp_addto_chunk(retval, sizeof(init), &init);
305 retval->param_hdr.v =
306 sctp_addto_chunk(retval, addrs_len, addrs.v);
307
308 /* RFC 2960 3.3.2 Initiation (INIT) (1)
309 *
310 * Note 4: This parameter, when present, specifies all the
311 * address types the sending endpoint can support. The absence
312 * of this parameter indicates that the sending endpoint can
313 * support any address type.
314 */
315 sat.param_hdr.type = SCTP_PARAM_SUPPORTED_ADDRESS_TYPES;
316 sat.param_hdr.length = htons(SCTP_SAT_LEN(num_types));
317 sctp_addto_chunk(retval, sizeof(sat), &sat);
318 sctp_addto_chunk(retval, num_types * sizeof(__u16), &types);
319
320 sctp_addto_chunk(retval, sizeof(ecap_param), &ecap_param);
321
322 /* Add the supported extensions parameter. Be nice and add this
323 * fist before addiding the parameters for the extensions themselves
324 */
325 if (num_ext) {
326 ext_param.param_hdr.type = SCTP_PARAM_SUPPORTED_EXT;
327 ext_param.param_hdr.length =
328 htons(sizeof(sctp_supported_ext_param_t) + num_ext);
329 sctp_addto_chunk(retval, sizeof(sctp_supported_ext_param_t),
330 &ext_param);
331 sctp_addto_param(retval, num_ext, extensions);
332 }
333
334 if (sctp_prsctp_enable)
335 sctp_addto_chunk(retval, sizeof(prsctp_param), &prsctp_param);
336
337 if (sp->adaptation_ind) {
338 aiparam.param_hdr.type = SCTP_PARAM_ADAPTATION_LAYER_IND;
339 aiparam.param_hdr.length = htons(sizeof(aiparam));
340 aiparam.adaptation_ind = htonl(sp->adaptation_ind);
341 sctp_addto_chunk(retval, sizeof(aiparam), &aiparam);
342 }
343
344 /* Add SCTP-AUTH chunks to the parameter list */
345 if (sctp_auth_enable) {
346 sctp_addto_chunk(retval, sizeof(asoc->c.auth_random),
347 asoc->c.auth_random);
348 if (auth_hmacs)
349 sctp_addto_chunk(retval, ntohs(auth_hmacs->length),
350 auth_hmacs);
351 if (auth_chunks)
352 sctp_addto_chunk(retval, ntohs(auth_chunks->length),
353 auth_chunks);
354 }
355 nodata:
356 kfree(addrs.v);
357 return retval;
358 }
359
360 struct sctp_chunk *sctp_make_init_ack(const struct sctp_association *asoc,
361 const struct sctp_chunk *chunk,
362 gfp_t gfp, int unkparam_len)
363 {
364 sctp_inithdr_t initack;
365 struct sctp_chunk *retval;
366 union sctp_params addrs;
367 struct sctp_sock *sp;
368 int addrs_len;
369 sctp_cookie_param_t *cookie;
370 int cookie_len;
371 size_t chunksize;
372 sctp_adaptation_ind_param_t aiparam;
373 sctp_supported_ext_param_t ext_param;
374 int num_ext = 0;
375 __u8 extensions[3];
376 sctp_paramhdr_t *auth_chunks = NULL,
377 *auth_hmacs = NULL,
378 *auth_random = NULL;
379
380 retval = NULL;
381
382 /* Note: there may be no addresses to embed. */
383 addrs = sctp_bind_addrs_to_raw(&asoc->base.bind_addr, &addrs_len, gfp);
384
385 initack.init_tag = htonl(asoc->c.my_vtag);
386 initack.a_rwnd = htonl(asoc->rwnd);
387 initack.num_outbound_streams = htons(asoc->c.sinit_num_ostreams);
388 initack.num_inbound_streams = htons(asoc->c.sinit_max_instreams);
389 initack.initial_tsn = htonl(asoc->c.initial_tsn);
390
391 /* FIXME: We really ought to build the cookie right
392 * into the packet instead of allocating more fresh memory.
393 */
394 cookie = sctp_pack_cookie(asoc->ep, asoc, chunk, &cookie_len,
395 addrs.v, addrs_len);
396 if (!cookie)
397 goto nomem_cookie;
398
399 /* Calculate the total size of allocation, include the reserved
400 * space for reporting unknown parameters if it is specified.
401 */
402 sp = sctp_sk(asoc->base.sk);
403 chunksize = sizeof(initack) + addrs_len + cookie_len + unkparam_len;
404
405 /* Tell peer that we'll do ECN only if peer advertised such cap. */
406 if (asoc->peer.ecn_capable)
407 chunksize += sizeof(ecap_param);
408
409 if (asoc->peer.prsctp_capable)
410 chunksize += sizeof(prsctp_param);
411
412 if (asoc->peer.asconf_capable) {
413 extensions[num_ext] = SCTP_CID_ASCONF;
414 extensions[num_ext+1] = SCTP_CID_ASCONF_ACK;
415 num_ext += 2;
416 }
417
418 if (sp->adaptation_ind)
419 chunksize += sizeof(aiparam);
420
421 if (asoc->peer.auth_capable) {
422 auth_random = (sctp_paramhdr_t *)asoc->c.auth_random;
423 chunksize += ntohs(auth_random->length);
424
425 auth_hmacs = (sctp_paramhdr_t *)asoc->c.auth_hmacs;
426 if (auth_hmacs->length)
427 chunksize += WORD_ROUND(ntohs(auth_hmacs->length));
428 else
429 auth_hmacs = NULL;
430
431 auth_chunks = (sctp_paramhdr_t *)asoc->c.auth_chunks;
432 if (auth_chunks->length)
433 chunksize += WORD_ROUND(ntohs(auth_chunks->length));
434 else
435 auth_chunks = NULL;
436
437 extensions[num_ext] = SCTP_CID_AUTH;
438 num_ext += 1;
439 }
440
441 if (num_ext)
442 chunksize += WORD_ROUND(sizeof(sctp_supported_ext_param_t) +
443 num_ext);
444
445 /* Now allocate and fill out the chunk. */
446 retval = sctp_make_chunk(asoc, SCTP_CID_INIT_ACK, 0, chunksize);
447 if (!retval)
448 goto nomem_chunk;
449
450 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
451 *
452 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
453 * HEARTBEAT ACK, * etc.) to the same destination transport
454 * address from which it received the DATA or control chunk
455 * to which it is replying.
456 *
457 * [INIT ACK back to where the INIT came from.]
458 */
459 retval->transport = chunk->transport;
460
461 retval->subh.init_hdr =
462 sctp_addto_chunk(retval, sizeof(initack), &initack);
463 retval->param_hdr.v = sctp_addto_chunk(retval, addrs_len, addrs.v);
464 sctp_addto_chunk(retval, cookie_len, cookie);
465 if (asoc->peer.ecn_capable)
466 sctp_addto_chunk(retval, sizeof(ecap_param), &ecap_param);
467 if (num_ext) {
468 ext_param.param_hdr.type = SCTP_PARAM_SUPPORTED_EXT;
469 ext_param.param_hdr.length =
470 htons(sizeof(sctp_supported_ext_param_t) + num_ext);
471 sctp_addto_chunk(retval, sizeof(sctp_supported_ext_param_t),
472 &ext_param);
473 sctp_addto_param(retval, num_ext, extensions);
474 }
475 if (asoc->peer.prsctp_capable)
476 sctp_addto_chunk(retval, sizeof(prsctp_param), &prsctp_param);
477
478 if (sp->adaptation_ind) {
479 aiparam.param_hdr.type = SCTP_PARAM_ADAPTATION_LAYER_IND;
480 aiparam.param_hdr.length = htons(sizeof(aiparam));
481 aiparam.adaptation_ind = htonl(sp->adaptation_ind);
482 sctp_addto_chunk(retval, sizeof(aiparam), &aiparam);
483 }
484
485 if (asoc->peer.auth_capable) {
486 sctp_addto_chunk(retval, ntohs(auth_random->length),
487 auth_random);
488 if (auth_hmacs)
489 sctp_addto_chunk(retval, ntohs(auth_hmacs->length),
490 auth_hmacs);
491 if (auth_chunks)
492 sctp_addto_chunk(retval, ntohs(auth_chunks->length),
493 auth_chunks);
494 }
495
496 /* We need to remove the const qualifier at this point. */
497 retval->asoc = (struct sctp_association *) asoc;
498
499 nomem_chunk:
500 kfree(cookie);
501 nomem_cookie:
502 kfree(addrs.v);
503 return retval;
504 }
505
506 /* 3.3.11 Cookie Echo (COOKIE ECHO) (10):
507 *
508 * This chunk is used only during the initialization of an association.
509 * It is sent by the initiator of an association to its peer to complete
510 * the initialization process. This chunk MUST precede any DATA chunk
511 * sent within the association, but MAY be bundled with one or more DATA
512 * chunks in the same packet.
513 *
514 * 0 1 2 3
515 * 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
516 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
517 * | Type = 10 |Chunk Flags | Length |
518 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
519 * / Cookie /
520 * \ \
521 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
522 *
523 * Chunk Flags: 8 bit
524 *
525 * Set to zero on transmit and ignored on receipt.
526 *
527 * Length: 16 bits (unsigned integer)
528 *
529 * Set to the size of the chunk in bytes, including the 4 bytes of
530 * the chunk header and the size of the Cookie.
531 *
532 * Cookie: variable size
533 *
534 * This field must contain the exact cookie received in the
535 * State Cookie parameter from the previous INIT ACK.
536 *
537 * An implementation SHOULD make the cookie as small as possible
538 * to insure interoperability.
539 */
540 struct sctp_chunk *sctp_make_cookie_echo(const struct sctp_association *asoc,
541 const struct sctp_chunk *chunk)
542 {
543 struct sctp_chunk *retval;
544 void *cookie;
545 int cookie_len;
546
547 cookie = asoc->peer.cookie;
548 cookie_len = asoc->peer.cookie_len;
549
550 /* Build a cookie echo chunk. */
551 retval = sctp_make_chunk(asoc, SCTP_CID_COOKIE_ECHO, 0, cookie_len);
552 if (!retval)
553 goto nodata;
554 retval->subh.cookie_hdr =
555 sctp_addto_chunk(retval, cookie_len, cookie);
556
557 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
558 *
559 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
560 * HEARTBEAT ACK, * etc.) to the same destination transport
561 * address from which it * received the DATA or control chunk
562 * to which it is replying.
563 *
564 * [COOKIE ECHO back to where the INIT ACK came from.]
565 */
566 if (chunk)
567 retval->transport = chunk->transport;
568
569 nodata:
570 return retval;
571 }
572
573 /* 3.3.12 Cookie Acknowledgement (COOKIE ACK) (11):
574 *
575 * This chunk is used only during the initialization of an
576 * association. It is used to acknowledge the receipt of a COOKIE
577 * ECHO chunk. This chunk MUST precede any DATA or SACK chunk sent
578 * within the association, but MAY be bundled with one or more DATA
579 * chunks or SACK chunk in the same SCTP packet.
580 *
581 * 0 1 2 3
582 * 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
583 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
584 * | Type = 11 |Chunk Flags | Length = 4 |
585 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
586 *
587 * Chunk Flags: 8 bits
588 *
589 * Set to zero on transmit and ignored on receipt.
590 */
591 struct sctp_chunk *sctp_make_cookie_ack(const struct sctp_association *asoc,
592 const struct sctp_chunk *chunk)
593 {
594 struct sctp_chunk *retval;
595
596 retval = sctp_make_chunk(asoc, SCTP_CID_COOKIE_ACK, 0, 0);
597
598 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
599 *
600 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
601 * HEARTBEAT ACK, * etc.) to the same destination transport
602 * address from which it * received the DATA or control chunk
603 * to which it is replying.
604 *
605 * [COOKIE ACK back to where the COOKIE ECHO came from.]
606 */
607 if (retval && chunk)
608 retval->transport = chunk->transport;
609
610 return retval;
611 }
612
613 /*
614 * Appendix A: Explicit Congestion Notification:
615 * CWR:
616 *
617 * RFC 2481 details a specific bit for a sender to send in the header of
618 * its next outbound TCP segment to indicate to its peer that it has
619 * reduced its congestion window. This is termed the CWR bit. For
620 * SCTP the same indication is made by including the CWR chunk.
621 * This chunk contains one data element, i.e. the TSN number that
622 * was sent in the ECNE chunk. This element represents the lowest
623 * TSN number in the datagram that was originally marked with the
624 * CE bit.
625 *
626 * 0 1 2 3
627 * 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
628 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
629 * | Chunk Type=13 | Flags=00000000| Chunk Length = 8 |
630 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
631 * | Lowest TSN Number |
632 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
633 *
634 * Note: The CWR is considered a Control chunk.
635 */
636 struct sctp_chunk *sctp_make_cwr(const struct sctp_association *asoc,
637 const __u32 lowest_tsn,
638 const struct sctp_chunk *chunk)
639 {
640 struct sctp_chunk *retval;
641 sctp_cwrhdr_t cwr;
642
643 cwr.lowest_tsn = htonl(lowest_tsn);
644 retval = sctp_make_chunk(asoc, SCTP_CID_ECN_CWR, 0,
645 sizeof(sctp_cwrhdr_t));
646
647 if (!retval)
648 goto nodata;
649
650 retval->subh.ecn_cwr_hdr =
651 sctp_addto_chunk(retval, sizeof(cwr), &cwr);
652
653 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
654 *
655 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
656 * HEARTBEAT ACK, * etc.) to the same destination transport
657 * address from which it * received the DATA or control chunk
658 * to which it is replying.
659 *
660 * [Report a reduced congestion window back to where the ECNE
661 * came from.]
662 */
663 if (chunk)
664 retval->transport = chunk->transport;
665
666 nodata:
667 return retval;
668 }
669
670 /* Make an ECNE chunk. This is a congestion experienced report. */
671 struct sctp_chunk *sctp_make_ecne(const struct sctp_association *asoc,
672 const __u32 lowest_tsn)
673 {
674 struct sctp_chunk *retval;
675 sctp_ecnehdr_t ecne;
676
677 ecne.lowest_tsn = htonl(lowest_tsn);
678 retval = sctp_make_chunk(asoc, SCTP_CID_ECN_ECNE, 0,
679 sizeof(sctp_ecnehdr_t));
680 if (!retval)
681 goto nodata;
682 retval->subh.ecne_hdr =
683 sctp_addto_chunk(retval, sizeof(ecne), &ecne);
684
685 nodata:
686 return retval;
687 }
688
689 /* Make a DATA chunk for the given association from the provided
690 * parameters. However, do not populate the data payload.
691 */
692 struct sctp_chunk *sctp_make_datafrag_empty(struct sctp_association *asoc,
693 const struct sctp_sndrcvinfo *sinfo,
694 int data_len, __u8 flags, __u16 ssn)
695 {
696 struct sctp_chunk *retval;
697 struct sctp_datahdr dp;
698 int chunk_len;
699
700 /* We assign the TSN as LATE as possible, not here when
701 * creating the chunk.
702 */
703 dp.tsn = 0;
704 dp.stream = htons(sinfo->sinfo_stream);
705 dp.ppid = sinfo->sinfo_ppid;
706
707 /* Set the flags for an unordered send. */
708 if (sinfo->sinfo_flags & SCTP_UNORDERED) {
709 flags |= SCTP_DATA_UNORDERED;
710 dp.ssn = 0;
711 } else
712 dp.ssn = htons(ssn);
713
714 chunk_len = sizeof(dp) + data_len;
715 retval = sctp_make_chunk(asoc, SCTP_CID_DATA, flags, chunk_len);
716 if (!retval)
717 goto nodata;
718
719 retval->subh.data_hdr = sctp_addto_chunk(retval, sizeof(dp), &dp);
720 memcpy(&retval->sinfo, sinfo, sizeof(struct sctp_sndrcvinfo));
721
722 nodata:
723 return retval;
724 }
725
726 /* Create a selective ackowledgement (SACK) for the given
727 * association. This reports on which TSN's we've seen to date,
728 * including duplicates and gaps.
729 */
730 struct sctp_chunk *sctp_make_sack(const struct sctp_association *asoc)
731 {
732 struct sctp_chunk *retval;
733 struct sctp_sackhdr sack;
734 int len;
735 __u32 ctsn;
736 __u16 num_gabs, num_dup_tsns;
737 struct sctp_tsnmap *map = (struct sctp_tsnmap *)&asoc->peer.tsn_map;
738 struct sctp_gap_ack_block gabs[SCTP_MAX_GABS];
739
740 memset(gabs, 0, sizeof(gabs));
741 ctsn = sctp_tsnmap_get_ctsn(map);
742 SCTP_DEBUG_PRINTK("sackCTSNAck sent: 0x%x.\n", ctsn);
743
744 /* How much room is needed in the chunk? */
745 num_gabs = sctp_tsnmap_num_gabs(map, gabs);
746 num_dup_tsns = sctp_tsnmap_num_dups(map);
747
748 /* Initialize the SACK header. */
749 sack.cum_tsn_ack = htonl(ctsn);
750 sack.a_rwnd = htonl(asoc->a_rwnd);
751 sack.num_gap_ack_blocks = htons(num_gabs);
752 sack.num_dup_tsns = htons(num_dup_tsns);
753
754 len = sizeof(sack)
755 + sizeof(struct sctp_gap_ack_block) * num_gabs
756 + sizeof(__u32) * num_dup_tsns;
757
758 /* Create the chunk. */
759 retval = sctp_make_chunk(asoc, SCTP_CID_SACK, 0, len);
760 if (!retval)
761 goto nodata;
762
763 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
764 *
765 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
766 * HEARTBEAT ACK, etc.) to the same destination transport
767 * address from which it received the DATA or control chunk to
768 * which it is replying. This rule should also be followed if
769 * the endpoint is bundling DATA chunks together with the
770 * reply chunk.
771 *
772 * However, when acknowledging multiple DATA chunks received
773 * in packets from different source addresses in a single
774 * SACK, the SACK chunk may be transmitted to one of the
775 * destination transport addresses from which the DATA or
776 * control chunks being acknowledged were received.
777 *
778 * [BUG: We do not implement the following paragraph.
779 * Perhaps we should remember the last transport we used for a
780 * SACK and avoid that (if possible) if we have seen any
781 * duplicates. --piggy]
782 *
783 * When a receiver of a duplicate DATA chunk sends a SACK to a
784 * multi- homed endpoint it MAY be beneficial to vary the
785 * destination address and not use the source address of the
786 * DATA chunk. The reason being that receiving a duplicate
787 * from a multi-homed endpoint might indicate that the return
788 * path (as specified in the source address of the DATA chunk)
789 * for the SACK is broken.
790 *
791 * [Send to the address from which we last received a DATA chunk.]
792 */
793 retval->transport = asoc->peer.last_data_from;
794
795 retval->subh.sack_hdr =
796 sctp_addto_chunk(retval, sizeof(sack), &sack);
797
798 /* Add the gap ack block information. */
799 if (num_gabs)
800 sctp_addto_chunk(retval, sizeof(__u32) * num_gabs,
801 gabs);
802
803 /* Add the duplicate TSN information. */
804 if (num_dup_tsns)
805 sctp_addto_chunk(retval, sizeof(__u32) * num_dup_tsns,
806 sctp_tsnmap_get_dups(map));
807
808 nodata:
809 return retval;
810 }
811
812 /* Make a SHUTDOWN chunk. */
813 struct sctp_chunk *sctp_make_shutdown(const struct sctp_association *asoc,
814 const struct sctp_chunk *chunk)
815 {
816 struct sctp_chunk *retval;
817 sctp_shutdownhdr_t shut;
818 __u32 ctsn;
819
820 ctsn = sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map);
821 shut.cum_tsn_ack = htonl(ctsn);
822
823 retval = sctp_make_chunk(asoc, SCTP_CID_SHUTDOWN, 0,
824 sizeof(sctp_shutdownhdr_t));
825 if (!retval)
826 goto nodata;
827
828 retval->subh.shutdown_hdr =
829 sctp_addto_chunk(retval, sizeof(shut), &shut);
830
831 if (chunk)
832 retval->transport = chunk->transport;
833 nodata:
834 return retval;
835 }
836
837 struct sctp_chunk *sctp_make_shutdown_ack(const struct sctp_association *asoc,
838 const struct sctp_chunk *chunk)
839 {
840 struct sctp_chunk *retval;
841
842 retval = sctp_make_chunk(asoc, SCTP_CID_SHUTDOWN_ACK, 0, 0);
843
844 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
845 *
846 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
847 * HEARTBEAT ACK, * etc.) to the same destination transport
848 * address from which it * received the DATA or control chunk
849 * to which it is replying.
850 *
851 * [ACK back to where the SHUTDOWN came from.]
852 */
853 if (retval && chunk)
854 retval->transport = chunk->transport;
855
856 return retval;
857 }
858
859 struct sctp_chunk *sctp_make_shutdown_complete(
860 const struct sctp_association *asoc,
861 const struct sctp_chunk *chunk)
862 {
863 struct sctp_chunk *retval;
864 __u8 flags = 0;
865
866 /* Set the T-bit if we have no association (vtag will be
867 * reflected)
868 */
869 flags |= asoc ? 0 : SCTP_CHUNK_FLAG_T;
870
871 retval = sctp_make_chunk(asoc, SCTP_CID_SHUTDOWN_COMPLETE, flags, 0);
872
873 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
874 *
875 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
876 * HEARTBEAT ACK, * etc.) to the same destination transport
877 * address from which it * received the DATA or control chunk
878 * to which it is replying.
879 *
880 * [Report SHUTDOWN COMPLETE back to where the SHUTDOWN ACK
881 * came from.]
882 */
883 if (retval && chunk)
884 retval->transport = chunk->transport;
885
886 return retval;
887 }
888
889 /* Create an ABORT. Note that we set the T bit if we have no
890 * association, except when responding to an INIT (sctpimpguide 2.41).
891 */
892 struct sctp_chunk *sctp_make_abort(const struct sctp_association *asoc,
893 const struct sctp_chunk *chunk,
894 const size_t hint)
895 {
896 struct sctp_chunk *retval;
897 __u8 flags = 0;
898
899 /* Set the T-bit if we have no association and 'chunk' is not
900 * an INIT (vtag will be reflected).
901 */
902 if (!asoc) {
903 if (chunk && chunk->chunk_hdr &&
904 chunk->chunk_hdr->type == SCTP_CID_INIT)
905 flags = 0;
906 else
907 flags = SCTP_CHUNK_FLAG_T;
908 }
909
910 retval = sctp_make_chunk(asoc, SCTP_CID_ABORT, flags, hint);
911
912 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
913 *
914 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
915 * HEARTBEAT ACK, * etc.) to the same destination transport
916 * address from which it * received the DATA or control chunk
917 * to which it is replying.
918 *
919 * [ABORT back to where the offender came from.]
920 */
921 if (retval && chunk)
922 retval->transport = chunk->transport;
923
924 return retval;
925 }
926
927 /* Helper to create ABORT with a NO_USER_DATA error. */
928 struct sctp_chunk *sctp_make_abort_no_data(
929 const struct sctp_association *asoc,
930 const struct sctp_chunk *chunk, __u32 tsn)
931 {
932 struct sctp_chunk *retval;
933 __be32 payload;
934
935 retval = sctp_make_abort(asoc, chunk, sizeof(sctp_errhdr_t)
936 + sizeof(tsn));
937
938 if (!retval)
939 goto no_mem;
940
941 /* Put the tsn back into network byte order. */
942 payload = htonl(tsn);
943 sctp_init_cause(retval, SCTP_ERROR_NO_DATA, sizeof(payload));
944 sctp_addto_chunk(retval, sizeof(payload), (const void *)&payload);
945
946 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
947 *
948 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
949 * HEARTBEAT ACK, * etc.) to the same destination transport
950 * address from which it * received the DATA or control chunk
951 * to which it is replying.
952 *
953 * [ABORT back to where the offender came from.]
954 */
955 if (chunk)
956 retval->transport = chunk->transport;
957
958 no_mem:
959 return retval;
960 }
961
962 /* Helper to create ABORT with a SCTP_ERROR_USER_ABORT error. */
963 struct sctp_chunk *sctp_make_abort_user(const struct sctp_association *asoc,
964 const struct msghdr *msg,
965 size_t paylen)
966 {
967 struct sctp_chunk *retval;
968 void *payload = NULL;
969 int err;
970
971 retval = sctp_make_abort(asoc, NULL, sizeof(sctp_errhdr_t) + paylen);
972 if (!retval)
973 goto err_chunk;
974
975 if (paylen) {
976 /* Put the msg_iov together into payload. */
977 payload = kmalloc(paylen, GFP_KERNEL);
978 if (!payload)
979 goto err_payload;
980
981 err = memcpy_fromiovec(payload, msg->msg_iov, paylen);
982 if (err < 0)
983 goto err_copy;
984 }
985
986 sctp_init_cause(retval, SCTP_ERROR_USER_ABORT, paylen);
987 sctp_addto_chunk(retval, paylen, payload);
988
989 if (paylen)
990 kfree(payload);
991
992 return retval;
993
994 err_copy:
995 kfree(payload);
996 err_payload:
997 sctp_chunk_free(retval);
998 retval = NULL;
999 err_chunk:
1000 return retval;
1001 }
1002
1003 /* Append bytes to the end of a parameter. Will panic if chunk is not big
1004 * enough.
1005 */
1006 static void *sctp_addto_param(struct sctp_chunk *chunk, int len,
1007 const void *data)
1008 {
1009 void *target;
1010 int chunklen = ntohs(chunk->chunk_hdr->length);
1011
1012 target = skb_put(chunk->skb, len);
1013
1014 if (data)
1015 memcpy(target, data, len);
1016 else
1017 memset(target, 0, len);
1018
1019 /* Adjust the chunk length field. */
1020 chunk->chunk_hdr->length = htons(chunklen + len);
1021 chunk->chunk_end = skb_tail_pointer(chunk->skb);
1022
1023 return target;
1024 }
1025
1026 /* Make an ABORT chunk with a PROTOCOL VIOLATION cause code. */
1027 struct sctp_chunk *sctp_make_abort_violation(
1028 const struct sctp_association *asoc,
1029 const struct sctp_chunk *chunk,
1030 const __u8 *payload,
1031 const size_t paylen)
1032 {
1033 struct sctp_chunk *retval;
1034 struct sctp_paramhdr phdr;
1035
1036 retval = sctp_make_abort(asoc, chunk, sizeof(sctp_errhdr_t) + paylen
1037 + sizeof(sctp_paramhdr_t));
1038 if (!retval)
1039 goto end;
1040
1041 sctp_init_cause(retval, SCTP_ERROR_PROTO_VIOLATION, paylen
1042 + sizeof(sctp_paramhdr_t));
1043
1044 phdr.type = htons(chunk->chunk_hdr->type);
1045 phdr.length = chunk->chunk_hdr->length;
1046 sctp_addto_chunk(retval, paylen, payload);
1047 sctp_addto_param(retval, sizeof(sctp_paramhdr_t), &phdr);
1048
1049 end:
1050 return retval;
1051 }
1052
1053 struct sctp_chunk *sctp_make_violation_paramlen(
1054 const struct sctp_association *asoc,
1055 const struct sctp_chunk *chunk,
1056 struct sctp_paramhdr *param)
1057 {
1058 struct sctp_chunk *retval;
1059 static const char error[] = "The following parameter had invalid length:";
1060 size_t payload_len = sizeof(error) + sizeof(sctp_errhdr_t) +
1061 sizeof(sctp_paramhdr_t);
1062
1063 retval = sctp_make_abort(asoc, chunk, payload_len);
1064 if (!retval)
1065 goto nodata;
1066
1067 sctp_init_cause(retval, SCTP_ERROR_PROTO_VIOLATION,
1068 sizeof(error) + sizeof(sctp_paramhdr_t));
1069 sctp_addto_chunk(retval, sizeof(error), error);
1070 sctp_addto_param(retval, sizeof(sctp_paramhdr_t), param);
1071
1072 nodata:
1073 return retval;
1074 }
1075
1076 /* Make a HEARTBEAT chunk. */
1077 struct sctp_chunk *sctp_make_heartbeat(const struct sctp_association *asoc,
1078 const struct sctp_transport *transport)
1079 {
1080 struct sctp_chunk *retval;
1081 sctp_sender_hb_info_t hbinfo;
1082
1083 retval = sctp_make_chunk(asoc, SCTP_CID_HEARTBEAT, 0, sizeof(hbinfo));
1084
1085 if (!retval)
1086 goto nodata;
1087
1088 hbinfo.param_hdr.type = SCTP_PARAM_HEARTBEAT_INFO;
1089 hbinfo.param_hdr.length = htons(sizeof(sctp_sender_hb_info_t));
1090 hbinfo.daddr = transport->ipaddr;
1091 hbinfo.sent_at = jiffies;
1092 hbinfo.hb_nonce = transport->hb_nonce;
1093
1094 /* Cast away the 'const', as this is just telling the chunk
1095 * what transport it belongs to.
1096 */
1097 retval->transport = (struct sctp_transport *) transport;
1098 retval->subh.hbs_hdr = sctp_addto_chunk(retval, sizeof(hbinfo),
1099 &hbinfo);
1100
1101 nodata:
1102 return retval;
1103 }
1104
1105 struct sctp_chunk *sctp_make_heartbeat_ack(const struct sctp_association *asoc,
1106 const struct sctp_chunk *chunk,
1107 const void *payload, const size_t paylen)
1108 {
1109 struct sctp_chunk *retval;
1110
1111 retval = sctp_make_chunk(asoc, SCTP_CID_HEARTBEAT_ACK, 0, paylen);
1112 if (!retval)
1113 goto nodata;
1114
1115 retval->subh.hbs_hdr = sctp_addto_chunk(retval, paylen, payload);
1116
1117 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
1118 *
1119 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
1120 * HEARTBEAT ACK, * etc.) to the same destination transport
1121 * address from which it * received the DATA or control chunk
1122 * to which it is replying.
1123 *
1124 * [HBACK back to where the HEARTBEAT came from.]
1125 */
1126 if (chunk)
1127 retval->transport = chunk->transport;
1128
1129 nodata:
1130 return retval;
1131 }
1132
1133 /* Create an Operation Error chunk with the specified space reserved.
1134 * This routine can be used for containing multiple causes in the chunk.
1135 */
1136 static struct sctp_chunk *sctp_make_op_error_space(
1137 const struct sctp_association *asoc,
1138 const struct sctp_chunk *chunk,
1139 size_t size)
1140 {
1141 struct sctp_chunk *retval;
1142
1143 retval = sctp_make_chunk(asoc, SCTP_CID_ERROR, 0,
1144 sizeof(sctp_errhdr_t) + size);
1145 if (!retval)
1146 goto nodata;
1147
1148 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
1149 *
1150 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
1151 * HEARTBEAT ACK, etc.) to the same destination transport
1152 * address from which it received the DATA or control chunk
1153 * to which it is replying.
1154 *
1155 */
1156 if (chunk)
1157 retval->transport = chunk->transport;
1158
1159 nodata:
1160 return retval;
1161 }
1162
1163 /* Create an Operation Error chunk of a fixed size,
1164 * specifically, max(asoc->pathmtu, SCTP_DEFAULT_MAXSEGMENT)
1165 * This is a helper function to allocate an error chunk for
1166 * for those invalid parameter codes in which we may not want
1167 * to report all the errors, if the incomming chunk is large
1168 */
1169 static inline struct sctp_chunk *sctp_make_op_error_fixed(
1170 const struct sctp_association *asoc,
1171 const struct sctp_chunk *chunk)
1172 {
1173 size_t size = asoc ? asoc->pathmtu : 0;
1174
1175 if (!size)
1176 size = SCTP_DEFAULT_MAXSEGMENT;
1177
1178 return sctp_make_op_error_space(asoc, chunk, size);
1179 }
1180
1181 /* Create an Operation Error chunk. */
1182 struct sctp_chunk *sctp_make_op_error(const struct sctp_association *asoc,
1183 const struct sctp_chunk *chunk,
1184 __be16 cause_code, const void *payload,
1185 size_t paylen, size_t reserve_tail)
1186 {
1187 struct sctp_chunk *retval;
1188
1189 retval = sctp_make_op_error_space(asoc, chunk, paylen + reserve_tail);
1190 if (!retval)
1191 goto nodata;
1192
1193 sctp_init_cause(retval, cause_code, paylen + reserve_tail);
1194 sctp_addto_chunk(retval, paylen, payload);
1195 if (reserve_tail)
1196 sctp_addto_param(retval, reserve_tail, NULL);
1197
1198 nodata:
1199 return retval;
1200 }
1201
1202 struct sctp_chunk *sctp_make_auth(const struct sctp_association *asoc)
1203 {
1204 struct sctp_chunk *retval;
1205 struct sctp_hmac *hmac_desc;
1206 struct sctp_authhdr auth_hdr;
1207 __u8 *hmac;
1208
1209 /* Get the first hmac that the peer told us to use */
1210 hmac_desc = sctp_auth_asoc_get_hmac(asoc);
1211 if (unlikely(!hmac_desc))
1212 return NULL;
1213
1214 retval = sctp_make_chunk(asoc, SCTP_CID_AUTH, 0,
1215 hmac_desc->hmac_len + sizeof(sctp_authhdr_t));
1216 if (!retval)
1217 return NULL;
1218
1219 auth_hdr.hmac_id = htons(hmac_desc->hmac_id);
1220 auth_hdr.shkey_id = htons(asoc->active_key_id);
1221
1222 retval->subh.auth_hdr = sctp_addto_chunk(retval, sizeof(sctp_authhdr_t),
1223 &auth_hdr);
1224
1225 hmac = skb_put(retval->skb, hmac_desc->hmac_len);
1226 memset(hmac, 0, hmac_desc->hmac_len);
1227
1228 /* Adjust the chunk header to include the empty MAC */
1229 retval->chunk_hdr->length =
1230 htons(ntohs(retval->chunk_hdr->length) + hmac_desc->hmac_len);
1231 retval->chunk_end = skb_tail_pointer(retval->skb);
1232
1233 return retval;
1234 }
1235
1236
1237 /********************************************************************
1238 * 2nd Level Abstractions
1239 ********************************************************************/
1240
1241 /* Turn an skb into a chunk.
1242 * FIXME: Eventually move the structure directly inside the skb->cb[].
1243 */
1244 struct sctp_chunk *sctp_chunkify(struct sk_buff *skb,
1245 const struct sctp_association *asoc,
1246 struct sock *sk)
1247 {
1248 struct sctp_chunk *retval;
1249
1250 retval = kmem_cache_zalloc(sctp_chunk_cachep, GFP_ATOMIC);
1251
1252 if (!retval)
1253 goto nodata;
1254
1255 if (!sk) {
1256 SCTP_DEBUG_PRINTK("chunkifying skb %p w/o an sk\n", skb);
1257 }
1258
1259 INIT_LIST_HEAD(&retval->list);
1260 retval->skb = skb;
1261 retval->asoc = (struct sctp_association *)asoc;
1262 retval->has_tsn = 0;
1263 retval->has_ssn = 0;
1264 retval->rtt_in_progress = 0;
1265 retval->sent_at = 0;
1266 retval->singleton = 1;
1267 retval->end_of_packet = 0;
1268 retval->ecn_ce_done = 0;
1269 retval->pdiscard = 0;
1270
1271 /* sctpimpguide-05.txt Section 2.8.2
1272 * M1) Each time a new DATA chunk is transmitted
1273 * set the 'TSN.Missing.Report' count for that TSN to 0. The
1274 * 'TSN.Missing.Report' count will be used to determine missing chunks
1275 * and when to fast retransmit.
1276 */
1277 retval->tsn_missing_report = 0;
1278 retval->tsn_gap_acked = 0;
1279 retval->fast_retransmit = SCTP_CAN_FRTX;
1280
1281 /* If this is a fragmented message, track all fragments
1282 * of the message (for SEND_FAILED).
1283 */
1284 retval->msg = NULL;
1285
1286 /* Polish the bead hole. */
1287 INIT_LIST_HEAD(&retval->transmitted_list);
1288 INIT_LIST_HEAD(&retval->frag_list);
1289 SCTP_DBG_OBJCNT_INC(chunk);
1290 atomic_set(&retval->refcnt, 1);
1291
1292 nodata:
1293 return retval;
1294 }
1295
1296 /* Set chunk->source and dest based on the IP header in chunk->skb. */
1297 void sctp_init_addrs(struct sctp_chunk *chunk, union sctp_addr *src,
1298 union sctp_addr *dest)
1299 {
1300 memcpy(&chunk->source, src, sizeof(union sctp_addr));
1301 memcpy(&chunk->dest, dest, sizeof(union sctp_addr));
1302 }
1303
1304 /* Extract the source address from a chunk. */
1305 const union sctp_addr *sctp_source(const struct sctp_chunk *chunk)
1306 {
1307 /* If we have a known transport, use that. */
1308 if (chunk->transport) {
1309 return &chunk->transport->ipaddr;
1310 } else {
1311 /* Otherwise, extract it from the IP header. */
1312 return &chunk->source;
1313 }
1314 }
1315
1316 /* Create a new chunk, setting the type and flags headers from the
1317 * arguments, reserving enough space for a 'paylen' byte payload.
1318 */
1319 SCTP_STATIC
1320 struct sctp_chunk *sctp_make_chunk(const struct sctp_association *asoc,
1321 __u8 type, __u8 flags, int paylen)
1322 {
1323 struct sctp_chunk *retval;
1324 sctp_chunkhdr_t *chunk_hdr;
1325 struct sk_buff *skb;
1326 struct sock *sk;
1327
1328 /* No need to allocate LL here, as this is only a chunk. */
1329 skb = alloc_skb(WORD_ROUND(sizeof(sctp_chunkhdr_t) + paylen),
1330 GFP_ATOMIC);
1331 if (!skb)
1332 goto nodata;
1333
1334 /* Make room for the chunk header. */
1335 chunk_hdr = (sctp_chunkhdr_t *)skb_put(skb, sizeof(sctp_chunkhdr_t));
1336 chunk_hdr->type = type;
1337 chunk_hdr->flags = flags;
1338 chunk_hdr->length = htons(sizeof(sctp_chunkhdr_t));
1339
1340 sk = asoc ? asoc->base.sk : NULL;
1341 retval = sctp_chunkify(skb, asoc, sk);
1342 if (!retval) {
1343 kfree_skb(skb);
1344 goto nodata;
1345 }
1346
1347 retval->chunk_hdr = chunk_hdr;
1348 retval->chunk_end = ((__u8 *)chunk_hdr) + sizeof(struct sctp_chunkhdr);
1349
1350 /* Determine if the chunk needs to be authenticated */
1351 if (sctp_auth_send_cid(type, asoc))
1352 retval->auth = 1;
1353
1354 /* Set the skb to the belonging sock for accounting. */
1355 skb->sk = sk;
1356
1357 return retval;
1358 nodata:
1359 return NULL;
1360 }
1361
1362
1363 /* Release the memory occupied by a chunk. */
1364 static void sctp_chunk_destroy(struct sctp_chunk *chunk)
1365 {
1366 BUG_ON(!list_empty(&chunk->list));
1367 list_del_init(&chunk->transmitted_list);
1368
1369 /* Free the chunk skb data and the SCTP_chunk stub itself. */
1370 dev_kfree_skb(chunk->skb);
1371
1372 SCTP_DBG_OBJCNT_DEC(chunk);
1373 kmem_cache_free(sctp_chunk_cachep, chunk);
1374 }
1375
1376 /* Possibly, free the chunk. */
1377 void sctp_chunk_free(struct sctp_chunk *chunk)
1378 {
1379 /* Release our reference on the message tracker. */
1380 if (chunk->msg)
1381 sctp_datamsg_put(chunk->msg);
1382
1383 sctp_chunk_put(chunk);
1384 }
1385
1386 /* Grab a reference to the chunk. */
1387 void sctp_chunk_hold(struct sctp_chunk *ch)
1388 {
1389 atomic_inc(&ch->refcnt);
1390 }
1391
1392 /* Release a reference to the chunk. */
1393 void sctp_chunk_put(struct sctp_chunk *ch)
1394 {
1395 if (atomic_dec_and_test(&ch->refcnt))
1396 sctp_chunk_destroy(ch);
1397 }
1398
1399 /* Append bytes to the end of a chunk. Will panic if chunk is not big
1400 * enough.
1401 */
1402 void *sctp_addto_chunk(struct sctp_chunk *chunk, int len, const void *data)
1403 {
1404 void *target;
1405 void *padding;
1406 int chunklen = ntohs(chunk->chunk_hdr->length);
1407 int padlen = WORD_ROUND(chunklen) - chunklen;
1408
1409 padding = skb_put(chunk->skb, padlen);
1410 target = skb_put(chunk->skb, len);
1411
1412 memset(padding, 0, padlen);
1413 memcpy(target, data, len);
1414
1415 /* Adjust the chunk length field. */
1416 chunk->chunk_hdr->length = htons(chunklen + padlen + len);
1417 chunk->chunk_end = skb_tail_pointer(chunk->skb);
1418
1419 return target;
1420 }
1421
1422 /* Append bytes to the end of a chunk. Returns NULL if there isn't sufficient
1423 * space in the chunk
1424 */
1425 void *sctp_addto_chunk_fixed(struct sctp_chunk *chunk,
1426 int len, const void *data)
1427 {
1428 if (skb_tailroom(chunk->skb) >= len)
1429 return sctp_addto_chunk(chunk, len, data);
1430 else
1431 return NULL;
1432 }
1433
1434 /* Append bytes from user space to the end of a chunk. Will panic if
1435 * chunk is not big enough.
1436 * Returns a kernel err value.
1437 */
1438 int sctp_user_addto_chunk(struct sctp_chunk *chunk, int off, int len,
1439 struct iovec *data)
1440 {
1441 __u8 *target;
1442 int err = 0;
1443
1444 /* Make room in chunk for data. */
1445 target = skb_put(chunk->skb, len);
1446
1447 /* Copy data (whole iovec) into chunk */
1448 if ((err = memcpy_fromiovecend(target, data, off, len)))
1449 goto out;
1450
1451 /* Adjust the chunk length field. */
1452 chunk->chunk_hdr->length =
1453 htons(ntohs(chunk->chunk_hdr->length) + len);
1454 chunk->chunk_end = skb_tail_pointer(chunk->skb);
1455
1456 out:
1457 return err;
1458 }
1459
1460 /* Helper function to assign a TSN if needed. This assumes that both
1461 * the data_hdr and association have already been assigned.
1462 */
1463 void sctp_chunk_assign_ssn(struct sctp_chunk *chunk)
1464 {
1465 struct sctp_datamsg *msg;
1466 struct sctp_chunk *lchunk;
1467 struct sctp_stream *stream;
1468 __u16 ssn;
1469 __u16 sid;
1470
1471 if (chunk->has_ssn)
1472 return;
1473
1474 /* All fragments will be on the same stream */
1475 sid = ntohs(chunk->subh.data_hdr->stream);
1476 stream = &chunk->asoc->ssnmap->out;
1477
1478 /* Now assign the sequence number to the entire message.
1479 * All fragments must have the same stream sequence number.
1480 */
1481 msg = chunk->msg;
1482 list_for_each_entry(lchunk, &msg->chunks, frag_list) {
1483 if (lchunk->chunk_hdr->flags & SCTP_DATA_UNORDERED) {
1484 ssn = 0;
1485 } else {
1486 if (lchunk->chunk_hdr->flags & SCTP_DATA_LAST_FRAG)
1487 ssn = sctp_ssn_next(stream, sid);
1488 else
1489 ssn = sctp_ssn_peek(stream, sid);
1490 }
1491
1492 lchunk->subh.data_hdr->ssn = htons(ssn);
1493 lchunk->has_ssn = 1;
1494 }
1495 }
1496
1497 /* Helper function to assign a TSN if needed. This assumes that both
1498 * the data_hdr and association have already been assigned.
1499 */
1500 void sctp_chunk_assign_tsn(struct sctp_chunk *chunk)
1501 {
1502 if (!chunk->has_tsn) {
1503 /* This is the last possible instant to
1504 * assign a TSN.
1505 */
1506 chunk->subh.data_hdr->tsn =
1507 htonl(sctp_association_get_next_tsn(chunk->asoc));
1508 chunk->has_tsn = 1;
1509 }
1510 }
1511
1512 /* Create a CLOSED association to use with an incoming packet. */
1513 struct sctp_association *sctp_make_temp_asoc(const struct sctp_endpoint *ep,
1514 struct sctp_chunk *chunk,
1515 gfp_t gfp)
1516 {
1517 struct sctp_association *asoc;
1518 struct sk_buff *skb;
1519 sctp_scope_t scope;
1520 struct sctp_af *af;
1521
1522 /* Create the bare association. */
1523 scope = sctp_scope(sctp_source(chunk));
1524 asoc = sctp_association_new(ep, ep->base.sk, scope, gfp);
1525 if (!asoc)
1526 goto nodata;
1527 asoc->temp = 1;
1528 skb = chunk->skb;
1529 /* Create an entry for the source address of the packet. */
1530 af = sctp_get_af_specific(ipver2af(ip_hdr(skb)->version));
1531 if (unlikely(!af))
1532 goto fail;
1533 af->from_skb(&asoc->c.peer_addr, skb, 1);
1534 nodata:
1535 return asoc;
1536
1537 fail:
1538 sctp_association_free(asoc);
1539 return NULL;
1540 }
1541
1542 /* Build a cookie representing asoc.
1543 * This INCLUDES the param header needed to put the cookie in the INIT ACK.
1544 */
1545 static sctp_cookie_param_t *sctp_pack_cookie(const struct sctp_endpoint *ep,
1546 const struct sctp_association *asoc,
1547 const struct sctp_chunk *init_chunk,
1548 int *cookie_len,
1549 const __u8 *raw_addrs, int addrs_len)
1550 {
1551 sctp_cookie_param_t *retval;
1552 struct sctp_signed_cookie *cookie;
1553 struct scatterlist sg;
1554 int headersize, bodysize;
1555 unsigned int keylen;
1556 char *key;
1557
1558 /* Header size is static data prior to the actual cookie, including
1559 * any padding.
1560 */
1561 headersize = sizeof(sctp_paramhdr_t) +
1562 (sizeof(struct sctp_signed_cookie) -
1563 sizeof(struct sctp_cookie));
1564 bodysize = sizeof(struct sctp_cookie)
1565 + ntohs(init_chunk->chunk_hdr->length) + addrs_len;
1566
1567 /* Pad out the cookie to a multiple to make the signature
1568 * functions simpler to write.
1569 */
1570 if (bodysize % SCTP_COOKIE_MULTIPLE)
1571 bodysize += SCTP_COOKIE_MULTIPLE
1572 - (bodysize % SCTP_COOKIE_MULTIPLE);
1573 *cookie_len = headersize + bodysize;
1574
1575 /* Clear this memory since we are sending this data structure
1576 * out on the network.
1577 */
1578 retval = kzalloc(*cookie_len, GFP_ATOMIC);
1579 if (!retval)
1580 goto nodata;
1581
1582 cookie = (struct sctp_signed_cookie *) retval->body;
1583
1584 /* Set up the parameter header. */
1585 retval->p.type = SCTP_PARAM_STATE_COOKIE;
1586 retval->p.length = htons(*cookie_len);
1587
1588 /* Copy the cookie part of the association itself. */
1589 cookie->c = asoc->c;
1590 /* Save the raw address list length in the cookie. */
1591 cookie->c.raw_addr_list_len = addrs_len;
1592
1593 /* Remember PR-SCTP capability. */
1594 cookie->c.prsctp_capable = asoc->peer.prsctp_capable;
1595
1596 /* Save adaptation indication in the cookie. */
1597 cookie->c.adaptation_ind = asoc->peer.adaptation_ind;
1598
1599 /* Set an expiration time for the cookie. */
1600 do_gettimeofday(&cookie->c.expiration);
1601 TIMEVAL_ADD(asoc->cookie_life, cookie->c.expiration);
1602
1603 /* Copy the peer's init packet. */
1604 memcpy(&cookie->c.peer_init[0], init_chunk->chunk_hdr,
1605 ntohs(init_chunk->chunk_hdr->length));
1606
1607 /* Copy the raw local address list of the association. */
1608 memcpy((__u8 *)&cookie->c.peer_init[0] +
1609 ntohs(init_chunk->chunk_hdr->length), raw_addrs, addrs_len);
1610
1611 if (sctp_sk(ep->base.sk)->hmac) {
1612 struct hash_desc desc;
1613
1614 /* Sign the message. */
1615 sg_init_one(&sg, &cookie->c, bodysize);
1616 keylen = SCTP_SECRET_SIZE;
1617 key = (char *)ep->secret_key[ep->current_key];
1618 desc.tfm = sctp_sk(ep->base.sk)->hmac;
1619 desc.flags = 0;
1620
1621 if (crypto_hash_setkey(desc.tfm, key, keylen) ||
1622 crypto_hash_digest(&desc, &sg, bodysize, cookie->signature))
1623 goto free_cookie;
1624 }
1625
1626 return retval;
1627
1628 free_cookie:
1629 kfree(retval);
1630 nodata:
1631 *cookie_len = 0;
1632 return NULL;
1633 }
1634
1635 /* Unpack the cookie from COOKIE ECHO chunk, recreating the association. */
1636 struct sctp_association *sctp_unpack_cookie(
1637 const struct sctp_endpoint *ep,
1638 const struct sctp_association *asoc,
1639 struct sctp_chunk *chunk, gfp_t gfp,
1640 int *error, struct sctp_chunk **errp)
1641 {
1642 struct sctp_association *retval = NULL;
1643 struct sctp_signed_cookie *cookie;
1644 struct sctp_cookie *bear_cookie;
1645 int headersize, bodysize, fixed_size;
1646 __u8 *digest = ep->digest;
1647 struct scatterlist sg;
1648 unsigned int keylen, len;
1649 char *key;
1650 sctp_scope_t scope;
1651 struct sk_buff *skb = chunk->skb;
1652 struct timeval tv;
1653 struct hash_desc desc;
1654
1655 /* Header size is static data prior to the actual cookie, including
1656 * any padding.
1657 */
1658 headersize = sizeof(sctp_chunkhdr_t) +
1659 (sizeof(struct sctp_signed_cookie) -
1660 sizeof(struct sctp_cookie));
1661 bodysize = ntohs(chunk->chunk_hdr->length) - headersize;
1662 fixed_size = headersize + sizeof(struct sctp_cookie);
1663
1664 /* Verify that the chunk looks like it even has a cookie.
1665 * There must be enough room for our cookie and our peer's
1666 * INIT chunk.
1667 */
1668 len = ntohs(chunk->chunk_hdr->length);
1669 if (len < fixed_size + sizeof(struct sctp_chunkhdr))
1670 goto malformed;
1671
1672 /* Verify that the cookie has been padded out. */
1673 if (bodysize % SCTP_COOKIE_MULTIPLE)
1674 goto malformed;
1675
1676 /* Process the cookie. */
1677 cookie = chunk->subh.cookie_hdr;
1678 bear_cookie = &cookie->c;
1679
1680 if (!sctp_sk(ep->base.sk)->hmac)
1681 goto no_hmac;
1682
1683 /* Check the signature. */
1684 keylen = SCTP_SECRET_SIZE;
1685 sg_init_one(&sg, bear_cookie, bodysize);
1686 key = (char *)ep->secret_key[ep->current_key];
1687 desc.tfm = sctp_sk(ep->base.sk)->hmac;
1688 desc.flags = 0;
1689
1690 memset(digest, 0x00, SCTP_SIGNATURE_SIZE);
1691 if (crypto_hash_setkey(desc.tfm, key, keylen) ||
1692 crypto_hash_digest(&desc, &sg, bodysize, digest)) {
1693 *error = -SCTP_IERROR_NOMEM;
1694 goto fail;
1695 }
1696
1697 if (memcmp(digest, cookie->signature, SCTP_SIGNATURE_SIZE)) {
1698 /* Try the previous key. */
1699 key = (char *)ep->secret_key[ep->last_key];
1700 memset(digest, 0x00, SCTP_SIGNATURE_SIZE);
1701 if (crypto_hash_setkey(desc.tfm, key, keylen) ||
1702 crypto_hash_digest(&desc, &sg, bodysize, digest)) {
1703 *error = -SCTP_IERROR_NOMEM;
1704 goto fail;
1705 }
1706
1707 if (memcmp(digest, cookie->signature, SCTP_SIGNATURE_SIZE)) {
1708 /* Yikes! Still bad signature! */
1709 *error = -SCTP_IERROR_BAD_SIG;
1710 goto fail;
1711 }
1712 }
1713
1714 no_hmac:
1715 /* IG Section 2.35.2:
1716 * 3) Compare the port numbers and the verification tag contained
1717 * within the COOKIE ECHO chunk to the actual port numbers and the
1718 * verification tag within the SCTP common header of the received
1719 * packet. If these values do not match the packet MUST be silently
1720 * discarded,
1721 */
1722 if (ntohl(chunk->sctp_hdr->vtag) != bear_cookie->my_vtag) {
1723 *error = -SCTP_IERROR_BAD_TAG;
1724 goto fail;
1725 }
1726
1727 if (chunk->sctp_hdr->source != bear_cookie->peer_addr.v4.sin_port ||
1728 ntohs(chunk->sctp_hdr->dest) != bear_cookie->my_port) {
1729 *error = -SCTP_IERROR_BAD_PORTS;
1730 goto fail;
1731 }
1732
1733 /* Check to see if the cookie is stale. If there is already
1734 * an association, there is no need to check cookie's expiration
1735 * for init collision case of lost COOKIE ACK.
1736 * If skb has been timestamped, then use the stamp, otherwise
1737 * use current time. This introduces a small possibility that
1738 * that a cookie may be considered expired, but his would only slow
1739 * down the new association establishment instead of every packet.
1740 */
1741 if (sock_flag(ep->base.sk, SOCK_TIMESTAMP))
1742 skb_get_timestamp(skb, &tv);
1743 else
1744 do_gettimeofday(&tv);
1745
1746 if (!asoc && tv_lt(bear_cookie->expiration, tv)) {
1747 /*
1748 * Section 3.3.10.3 Stale Cookie Error (3)
1749 *
1750 * Cause of error
1751 * ---------------
1752 * Stale Cookie Error: Indicates the receipt of a valid State
1753 * Cookie that has expired.
1754 */
1755 len = ntohs(chunk->chunk_hdr->length);
1756 *errp = sctp_make_op_error_space(asoc, chunk, len);
1757 if (*errp) {
1758 suseconds_t usecs = (tv.tv_sec -
1759 bear_cookie->expiration.tv_sec) * 1000000L +
1760 tv.tv_usec - bear_cookie->expiration.tv_usec;
1761 __be32 n = htonl(usecs);
1762
1763 sctp_init_cause(*errp, SCTP_ERROR_STALE_COOKIE,
1764 sizeof(n));
1765 sctp_addto_chunk(*errp, sizeof(n), &n);
1766 *error = -SCTP_IERROR_STALE_COOKIE;
1767 } else
1768 *error = -SCTP_IERROR_NOMEM;
1769
1770 goto fail;
1771 }
1772
1773 /* Make a new base association. */
1774 scope = sctp_scope(sctp_source(chunk));
1775 retval = sctp_association_new(ep, ep->base.sk, scope, gfp);
1776 if (!retval) {
1777 *error = -SCTP_IERROR_NOMEM;
1778 goto fail;
1779 }
1780
1781 /* Set up our peer's port number. */
1782 retval->peer.port = ntohs(chunk->sctp_hdr->source);
1783
1784 /* Populate the association from the cookie. */
1785 memcpy(&retval->c, bear_cookie, sizeof(*bear_cookie));
1786
1787 if (sctp_assoc_set_bind_addr_from_cookie(retval, bear_cookie,
1788 GFP_ATOMIC) < 0) {
1789 *error = -SCTP_IERROR_NOMEM;
1790 goto fail;
1791 }
1792
1793 /* Also, add the destination address. */
1794 if (list_empty(&retval->base.bind_addr.address_list)) {
1795 sctp_add_bind_addr(&retval->base.bind_addr, &chunk->dest,
1796 SCTP_ADDR_SRC, GFP_ATOMIC);
1797 }
1798
1799 retval->next_tsn = retval->c.initial_tsn;
1800 retval->ctsn_ack_point = retval->next_tsn - 1;
1801 retval->addip_serial = retval->c.initial_tsn;
1802 retval->adv_peer_ack_point = retval->ctsn_ack_point;
1803 retval->peer.prsctp_capable = retval->c.prsctp_capable;
1804 retval->peer.adaptation_ind = retval->c.adaptation_ind;
1805
1806 /* The INIT stuff will be done by the side effects. */
1807 return retval;
1808
1809 fail:
1810 if (retval)
1811 sctp_association_free(retval);
1812
1813 return NULL;
1814
1815 malformed:
1816 /* Yikes! The packet is either corrupt or deliberately
1817 * malformed.
1818 */
1819 *error = -SCTP_IERROR_MALFORMED;
1820 goto fail;
1821 }
1822
1823 /********************************************************************
1824 * 3rd Level Abstractions
1825 ********************************************************************/
1826
1827 struct __sctp_missing {
1828 __be32 num_missing;
1829 __be16 type;
1830 } __packed;
1831
1832 /*
1833 * Report a missing mandatory parameter.
1834 */
1835 static int sctp_process_missing_param(const struct sctp_association *asoc,
1836 sctp_param_t paramtype,
1837 struct sctp_chunk *chunk,
1838 struct sctp_chunk **errp)
1839 {
1840 struct __sctp_missing report;
1841 __u16 len;
1842
1843 len = WORD_ROUND(sizeof(report));
1844
1845 /* Make an ERROR chunk, preparing enough room for
1846 * returning multiple unknown parameters.
1847 */
1848 if (!*errp)
1849 *errp = sctp_make_op_error_space(asoc, chunk, len);
1850
1851 if (*errp) {
1852 report.num_missing = htonl(1);
1853 report.type = paramtype;
1854 sctp_init_cause(*errp, SCTP_ERROR_MISS_PARAM,
1855 sizeof(report));
1856 sctp_addto_chunk(*errp, sizeof(report), &report);
1857 }
1858
1859 /* Stop processing this chunk. */
1860 return 0;
1861 }
1862
1863 /* Report an Invalid Mandatory Parameter. */
1864 static int sctp_process_inv_mandatory(const struct sctp_association *asoc,
1865 struct sctp_chunk *chunk,
1866 struct sctp_chunk **errp)
1867 {
1868 /* Invalid Mandatory Parameter Error has no payload. */
1869
1870 if (!*errp)
1871 *errp = sctp_make_op_error_space(asoc, chunk, 0);
1872
1873 if (*errp)
1874 sctp_init_cause(*errp, SCTP_ERROR_INV_PARAM, 0);
1875
1876 /* Stop processing this chunk. */
1877 return 0;
1878 }
1879
1880 static int sctp_process_inv_paramlength(const struct sctp_association *asoc,
1881 struct sctp_paramhdr *param,
1882 const struct sctp_chunk *chunk,
1883 struct sctp_chunk **errp)
1884 {
1885 /* This is a fatal error. Any accumulated non-fatal errors are
1886 * not reported.
1887 */
1888 if (*errp)
1889 sctp_chunk_free(*errp);
1890
1891 /* Create an error chunk and fill it in with our payload. */
1892 *errp = sctp_make_violation_paramlen(asoc, chunk, param);
1893
1894 return 0;
1895 }
1896
1897
1898 /* Do not attempt to handle the HOST_NAME parm. However, do
1899 * send back an indicator to the peer.
1900 */
1901 static int sctp_process_hn_param(const struct sctp_association *asoc,
1902 union sctp_params param,
1903 struct sctp_chunk *chunk,
1904 struct sctp_chunk **errp)
1905 {
1906 __u16 len = ntohs(param.p->length);
1907
1908 /* Processing of the HOST_NAME parameter will generate an
1909 * ABORT. If we've accumulated any non-fatal errors, they
1910 * would be unrecognized parameters and we should not include
1911 * them in the ABORT.
1912 */
1913 if (*errp)
1914 sctp_chunk_free(*errp);
1915
1916 *errp = sctp_make_op_error_space(asoc, chunk, len);
1917
1918 if (*errp) {
1919 sctp_init_cause(*errp, SCTP_ERROR_DNS_FAILED, len);
1920 sctp_addto_chunk(*errp, len, param.v);
1921 }
1922
1923 /* Stop processing this chunk. */
1924 return 0;
1925 }
1926
1927 static int sctp_verify_ext_param(union sctp_params param)
1928 {
1929 __u16 num_ext = ntohs(param.p->length) - sizeof(sctp_paramhdr_t);
1930 int have_auth = 0;
1931 int have_asconf = 0;
1932 int i;
1933
1934 for (i = 0; i < num_ext; i++) {
1935 switch (param.ext->chunks[i]) {
1936 case SCTP_CID_AUTH:
1937 have_auth = 1;
1938 break;
1939 case SCTP_CID_ASCONF:
1940 case SCTP_CID_ASCONF_ACK:
1941 have_asconf = 1;
1942 break;
1943 }
1944 }
1945
1946 /* ADD-IP Security: The draft requires us to ABORT or ignore the
1947 * INIT/INIT-ACK if ADD-IP is listed, but AUTH is not. Do this
1948 * only if ADD-IP is turned on and we are not backward-compatible
1949 * mode.
1950 */
1951 if (sctp_addip_noauth)
1952 return 1;
1953
1954 if (sctp_addip_enable && !have_auth && have_asconf)
1955 return 0;
1956
1957 return 1;
1958 }
1959
1960 static void sctp_process_ext_param(struct sctp_association *asoc,
1961 union sctp_params param)
1962 {
1963 __u16 num_ext = ntohs(param.p->length) - sizeof(sctp_paramhdr_t);
1964 int i;
1965
1966 for (i = 0; i < num_ext; i++) {
1967 switch (param.ext->chunks[i]) {
1968 case SCTP_CID_FWD_TSN:
1969 if (sctp_prsctp_enable &&
1970 !asoc->peer.prsctp_capable)
1971 asoc->peer.prsctp_capable = 1;
1972 break;
1973 case SCTP_CID_AUTH:
1974 /* if the peer reports AUTH, assume that he
1975 * supports AUTH.
1976 */
1977 if (sctp_auth_enable)
1978 asoc->peer.auth_capable = 1;
1979 break;
1980 case SCTP_CID_ASCONF:
1981 case SCTP_CID_ASCONF_ACK:
1982 if (sctp_addip_enable)
1983 asoc->peer.asconf_capable = 1;
1984 break;
1985 default:
1986 break;
1987 }
1988 }
1989 }
1990
1991 /* RFC 3.2.1 & the Implementers Guide 2.2.
1992 *
1993 * The Parameter Types are encoded such that the
1994 * highest-order two bits specify the action that must be
1995 * taken if the processing endpoint does not recognize the
1996 * Parameter Type.
1997 *
1998 * 00 - Stop processing this parameter; do not process any further
1999 * parameters within this chunk
2000 *
2001 * 01 - Stop processing this parameter, do not process any further
2002 * parameters within this chunk, and report the unrecognized
2003 * parameter in an 'Unrecognized Parameter' ERROR chunk.
2004 *
2005 * 10 - Skip this parameter and continue processing.
2006 *
2007 * 11 - Skip this parameter and continue processing but
2008 * report the unrecognized parameter in an
2009 * 'Unrecognized Parameter' ERROR chunk.
2010 *
2011 * Return value:
2012 * SCTP_IERROR_NO_ERROR - continue with the chunk
2013 * SCTP_IERROR_ERROR - stop and report an error.
2014 * SCTP_IERROR_NOMEME - out of memory.
2015 */
2016 static sctp_ierror_t sctp_process_unk_param(const struct sctp_association *asoc,
2017 union sctp_params param,
2018 struct sctp_chunk *chunk,
2019 struct sctp_chunk **errp)
2020 {
2021 int retval = SCTP_IERROR_NO_ERROR;
2022
2023 switch (param.p->type & SCTP_PARAM_ACTION_MASK) {
2024 case SCTP_PARAM_ACTION_DISCARD:
2025 retval = SCTP_IERROR_ERROR;
2026 break;
2027 case SCTP_PARAM_ACTION_SKIP:
2028 break;
2029 case SCTP_PARAM_ACTION_DISCARD_ERR:
2030 retval = SCTP_IERROR_ERROR;
2031 /* Fall through */
2032 case SCTP_PARAM_ACTION_SKIP_ERR:
2033 /* Make an ERROR chunk, preparing enough room for
2034 * returning multiple unknown parameters.
2035 */
2036 if (NULL == *errp)
2037 *errp = sctp_make_op_error_fixed(asoc, chunk);
2038
2039 if (*errp) {
2040 if (!sctp_init_cause_fixed(*errp, SCTP_ERROR_UNKNOWN_PARAM,
2041 WORD_ROUND(ntohs(param.p->length))))
2042 sctp_addto_chunk_fixed(*errp,
2043 WORD_ROUND(ntohs(param.p->length)),
2044 param.v);
2045 } else {
2046 /* If there is no memory for generating the ERROR
2047 * report as specified, an ABORT will be triggered
2048 * to the peer and the association won't be
2049 * established.
2050 */
2051 retval = SCTP_IERROR_NOMEM;
2052 }
2053 break;
2054 default:
2055 break;
2056 }
2057
2058 return retval;
2059 }
2060
2061 /* Verify variable length parameters
2062 * Return values:
2063 * SCTP_IERROR_ABORT - trigger an ABORT
2064 * SCTP_IERROR_NOMEM - out of memory (abort)
2065 * SCTP_IERROR_ERROR - stop processing, trigger an ERROR
2066 * SCTP_IERROR_NO_ERROR - continue with the chunk
2067 */
2068 static sctp_ierror_t sctp_verify_param(const struct sctp_association *asoc,
2069 union sctp_params param,
2070 sctp_cid_t cid,
2071 struct sctp_chunk *chunk,
2072 struct sctp_chunk **err_chunk)
2073 {
2074 struct sctp_hmac_algo_param *hmacs;
2075 int retval = SCTP_IERROR_NO_ERROR;
2076 __u16 n_elt, id = 0;
2077 int i;
2078
2079 /* FIXME - This routine is not looking at each parameter per the
2080 * chunk type, i.e., unrecognized parameters should be further
2081 * identified based on the chunk id.
2082 */
2083
2084 switch (param.p->type) {
2085 case SCTP_PARAM_IPV4_ADDRESS:
2086 case SCTP_PARAM_IPV6_ADDRESS:
2087 case SCTP_PARAM_COOKIE_PRESERVATIVE:
2088 case SCTP_PARAM_SUPPORTED_ADDRESS_TYPES:
2089 case SCTP_PARAM_STATE_COOKIE:
2090 case SCTP_PARAM_HEARTBEAT_INFO:
2091 case SCTP_PARAM_UNRECOGNIZED_PARAMETERS:
2092 case SCTP_PARAM_ECN_CAPABLE:
2093 case SCTP_PARAM_ADAPTATION_LAYER_IND:
2094 break;
2095
2096 case SCTP_PARAM_SUPPORTED_EXT:
2097 if (!sctp_verify_ext_param(param))
2098 return SCTP_IERROR_ABORT;
2099 break;
2100
2101 case SCTP_PARAM_SET_PRIMARY:
2102 if (sctp_addip_enable)
2103 break;
2104 goto fallthrough;
2105
2106 case SCTP_PARAM_HOST_NAME_ADDRESS:
2107 /* Tell the peer, we won't support this param. */
2108 sctp_process_hn_param(asoc, param, chunk, err_chunk);
2109 retval = SCTP_IERROR_ABORT;
2110 break;
2111
2112 case SCTP_PARAM_FWD_TSN_SUPPORT:
2113 if (sctp_prsctp_enable)
2114 break;
2115 goto fallthrough;
2116
2117 case SCTP_PARAM_RANDOM:
2118 if (!sctp_auth_enable)
2119 goto fallthrough;
2120
2121 /* SCTP-AUTH: Secion 6.1
2122 * If the random number is not 32 byte long the association
2123 * MUST be aborted. The ABORT chunk SHOULD contain the error
2124 * cause 'Protocol Violation'.
2125 */
2126 if (SCTP_AUTH_RANDOM_LENGTH !=
2127 ntohs(param.p->length) - sizeof(sctp_paramhdr_t)) {
2128 sctp_process_inv_paramlength(asoc, param.p,
2129 chunk, err_chunk);
2130 retval = SCTP_IERROR_ABORT;
2131 }
2132 break;
2133
2134 case SCTP_PARAM_CHUNKS:
2135 if (!sctp_auth_enable)
2136 goto fallthrough;
2137
2138 /* SCTP-AUTH: Section 3.2
2139 * The CHUNKS parameter MUST be included once in the INIT or
2140 * INIT-ACK chunk if the sender wants to receive authenticated
2141 * chunks. Its maximum length is 260 bytes.
2142 */
2143 if (260 < ntohs(param.p->length)) {
2144 sctp_process_inv_paramlength(asoc, param.p,
2145 chunk, err_chunk);
2146 retval = SCTP_IERROR_ABORT;
2147 }
2148 break;
2149
2150 case SCTP_PARAM_HMAC_ALGO:
2151 if (!sctp_auth_enable)
2152 goto fallthrough;
2153
2154 hmacs = (struct sctp_hmac_algo_param *)param.p;
2155 n_elt = (ntohs(param.p->length) - sizeof(sctp_paramhdr_t)) >> 1;
2156
2157 /* SCTP-AUTH: Section 6.1
2158 * The HMAC algorithm based on SHA-1 MUST be supported and
2159 * included in the HMAC-ALGO parameter.
2160 */
2161 for (i = 0; i < n_elt; i++) {
2162 id = ntohs(hmacs->hmac_ids[i]);
2163
2164 if (id == SCTP_AUTH_HMAC_ID_SHA1)
2165 break;
2166 }
2167
2168 if (id != SCTP_AUTH_HMAC_ID_SHA1) {
2169 sctp_process_inv_paramlength(asoc, param.p, chunk,
2170 err_chunk);
2171 retval = SCTP_IERROR_ABORT;
2172 }
2173 break;
2174 fallthrough:
2175 default:
2176 SCTP_DEBUG_PRINTK("Unrecognized param: %d for chunk %d.\n",
2177 ntohs(param.p->type), cid);
2178 retval = sctp_process_unk_param(asoc, param, chunk, err_chunk);
2179 break;
2180 }
2181 return retval;
2182 }
2183
2184 /* Verify the INIT packet before we process it. */
2185 int sctp_verify_init(const struct sctp_association *asoc,
2186 sctp_cid_t cid,
2187 sctp_init_chunk_t *peer_init,
2188 struct sctp_chunk *chunk,
2189 struct sctp_chunk **errp)
2190 {
2191 union sctp_params param;
2192 int has_cookie = 0;
2193 int result;
2194
2195 /* Verify stream values are non-zero. */
2196 if ((0 == peer_init->init_hdr.num_outbound_streams) ||
2197 (0 == peer_init->init_hdr.num_inbound_streams) ||
2198 (0 == peer_init->init_hdr.init_tag) ||
2199 (SCTP_DEFAULT_MINWINDOW > ntohl(peer_init->init_hdr.a_rwnd))) {
2200
2201 return sctp_process_inv_mandatory(asoc, chunk, errp);
2202 }
2203
2204 /* Check for missing mandatory parameters. */
2205 sctp_walk_params(param, peer_init, init_hdr.params) {
2206
2207 if (SCTP_PARAM_STATE_COOKIE == param.p->type)
2208 has_cookie = 1;
2209
2210 } /* for (loop through all parameters) */
2211
2212 /* There is a possibility that a parameter length was bad and
2213 * in that case we would have stoped walking the parameters.
2214 * The current param.p would point at the bad one.
2215 * Current consensus on the mailing list is to generate a PROTOCOL
2216 * VIOLATION error. We build the ERROR chunk here and let the normal
2217 * error handling code build and send the packet.
2218 */
2219 if (param.v != (void*)chunk->chunk_end)
2220 return sctp_process_inv_paramlength(asoc, param.p, chunk, errp);
2221
2222 /* The only missing mandatory param possible today is
2223 * the state cookie for an INIT-ACK chunk.
2224 */
2225 if ((SCTP_CID_INIT_ACK == cid) && !has_cookie)
2226 return sctp_process_missing_param(asoc, SCTP_PARAM_STATE_COOKIE,
2227 chunk, errp);
2228
2229 /* Verify all the variable length parameters */
2230 sctp_walk_params(param, peer_init, init_hdr.params) {
2231
2232 result = sctp_verify_param(asoc, param, cid, chunk, errp);
2233 switch (result) {
2234 case SCTP_IERROR_ABORT:
2235 case SCTP_IERROR_NOMEM:
2236 return 0;
2237 case SCTP_IERROR_ERROR:
2238 return 1;
2239 case SCTP_IERROR_NO_ERROR:
2240 default:
2241 break;
2242 }
2243
2244 } /* for (loop through all parameters) */
2245
2246 return 1;
2247 }
2248
2249 /* Unpack the parameters in an INIT packet into an association.
2250 * Returns 0 on failure, else success.
2251 * FIXME: This is an association method.
2252 */
2253 int sctp_process_init(struct sctp_association *asoc, struct sctp_chunk *chunk,
2254 const union sctp_addr *peer_addr,
2255 sctp_init_chunk_t *peer_init, gfp_t gfp)
2256 {
2257 union sctp_params param;
2258 struct sctp_transport *transport;
2259 struct list_head *pos, *temp;
2260 struct sctp_af *af;
2261 union sctp_addr addr;
2262 char *cookie;
2263 int src_match = 0;
2264
2265 /* We must include the address that the INIT packet came from.
2266 * This is the only address that matters for an INIT packet.
2267 * When processing a COOKIE ECHO, we retrieve the from address
2268 * of the INIT from the cookie.
2269 */
2270
2271 /* This implementation defaults to making the first transport
2272 * added as the primary transport. The source address seems to
2273 * be a a better choice than any of the embedded addresses.
2274 */
2275 if(!sctp_assoc_add_peer(asoc, peer_addr, gfp, SCTP_ACTIVE))
2276 goto nomem;
2277
2278 if (sctp_cmp_addr_exact(sctp_source(chunk), peer_addr))
2279 src_match = 1;
2280
2281 /* Process the initialization parameters. */
2282 sctp_walk_params(param, peer_init, init_hdr.params) {
2283 if (!src_match && (param.p->type == SCTP_PARAM_IPV4_ADDRESS ||
2284 param.p->type == SCTP_PARAM_IPV6_ADDRESS)) {
2285 af = sctp_get_af_specific(param_type2af(param.p->type));
2286 af->from_addr_param(&addr, param.addr,
2287 chunk->sctp_hdr->source, 0);
2288 if (sctp_cmp_addr_exact(sctp_source(chunk), &addr))
2289 src_match = 1;
2290 }
2291
2292 if (!sctp_process_param(asoc, param, peer_addr, gfp))
2293 goto clean_up;
2294 }
2295
2296 /* source address of chunk may not match any valid address */
2297 if (!src_match)
2298 goto clean_up;
2299
2300 /* AUTH: After processing the parameters, make sure that we
2301 * have all the required info to potentially do authentications.
2302 */
2303 if (asoc->peer.auth_capable && (!asoc->peer.peer_random ||
2304 !asoc->peer.peer_hmacs))
2305 asoc->peer.auth_capable = 0;
2306
2307 /* In a non-backward compatible mode, if the peer claims
2308 * support for ADD-IP but not AUTH, the ADD-IP spec states
2309 * that we MUST ABORT the association. Section 6. The section
2310 * also give us an option to silently ignore the packet, which
2311 * is what we'll do here.
2312 */
2313 if (!sctp_addip_noauth &&
2314 (asoc->peer.asconf_capable && !asoc->peer.auth_capable)) {
2315 asoc->peer.addip_disabled_mask |= (SCTP_PARAM_ADD_IP |
2316 SCTP_PARAM_DEL_IP |
2317 SCTP_PARAM_SET_PRIMARY);
2318 asoc->peer.asconf_capable = 0;
2319 goto clean_up;
2320 }
2321
2322 /* Walk list of transports, removing transports in the UNKNOWN state. */
2323 list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
2324 transport = list_entry(pos, struct sctp_transport, transports);
2325 if (transport->state == SCTP_UNKNOWN) {
2326 sctp_assoc_rm_peer(asoc, transport);
2327 }
2328 }
2329
2330 /* The fixed INIT headers are always in network byte
2331 * order.
2332 */
2333 asoc->peer.i.init_tag =
2334 ntohl(peer_init->init_hdr.init_tag);
2335 asoc->peer.i.a_rwnd =
2336 ntohl(peer_init->init_hdr.a_rwnd);
2337 asoc->peer.i.num_outbound_streams =
2338 ntohs(peer_init->init_hdr.num_outbound_streams);
2339 asoc->peer.i.num_inbound_streams =
2340 ntohs(peer_init->init_hdr.num_inbound_streams);
2341 asoc->peer.i.initial_tsn =
2342 ntohl(peer_init->init_hdr.initial_tsn);
2343
2344 /* Apply the upper bounds for output streams based on peer's
2345 * number of inbound streams.
2346 */
2347 if (asoc->c.sinit_num_ostreams >
2348 ntohs(peer_init->init_hdr.num_inbound_streams)) {
2349 asoc->c.sinit_num_ostreams =
2350 ntohs(peer_init->init_hdr.num_inbound_streams);
2351 }
2352
2353 if (asoc->c.sinit_max_instreams >
2354 ntohs(peer_init->init_hdr.num_outbound_streams)) {
2355 asoc->c.sinit_max_instreams =
2356 ntohs(peer_init->init_hdr.num_outbound_streams);
2357 }
2358
2359 /* Copy Initiation tag from INIT to VT_peer in cookie. */
2360 asoc->c.peer_vtag = asoc->peer.i.init_tag;
2361
2362 /* Peer Rwnd : Current calculated value of the peer's rwnd. */
2363 asoc->peer.rwnd = asoc->peer.i.a_rwnd;
2364
2365 /* Copy cookie in case we need to resend COOKIE-ECHO. */
2366 cookie = asoc->peer.cookie;
2367 if (cookie) {
2368 asoc->peer.cookie = kmemdup(cookie, asoc->peer.cookie_len, gfp);
2369 if (!asoc->peer.cookie)
2370 goto clean_up;
2371 }
2372
2373 /* RFC 2960 7.2.1 The initial value of ssthresh MAY be arbitrarily
2374 * high (for example, implementations MAY use the size of the receiver
2375 * advertised window).
2376 */
2377 list_for_each_entry(transport, &asoc->peer.transport_addr_list,
2378 transports) {
2379 transport->ssthresh = asoc->peer.i.a_rwnd;
2380 }
2381
2382 /* Set up the TSN tracking pieces. */
2383 if (!sctp_tsnmap_init(&asoc->peer.tsn_map, SCTP_TSN_MAP_INITIAL,
2384 asoc->peer.i.initial_tsn, gfp))
2385 goto clean_up;
2386
2387 /* RFC 2960 6.5 Stream Identifier and Stream Sequence Number
2388 *
2389 * The stream sequence number in all the streams shall start
2390 * from 0 when the association is established. Also, when the
2391 * stream sequence number reaches the value 65535 the next
2392 * stream sequence number shall be set to 0.
2393 */
2394
2395 /* Allocate storage for the negotiated streams if it is not a temporary
2396 * association.
2397 */
2398 if (!asoc->temp) {
2399 int error;
2400
2401 asoc->ssnmap = sctp_ssnmap_new(asoc->c.sinit_max_instreams,
2402 asoc->c.sinit_num_ostreams, gfp);
2403 if (!asoc->ssnmap)
2404 goto clean_up;
2405
2406 error = sctp_assoc_set_id(asoc, gfp);
2407 if (error)
2408 goto clean_up;
2409 }
2410
2411 /* ADDIP Section 4.1 ASCONF Chunk Procedures
2412 *
2413 * When an endpoint has an ASCONF signaled change to be sent to the
2414 * remote endpoint it should do the following:
2415 * ...
2416 * A2) A serial number should be assigned to the Chunk. The serial
2417 * number should be a monotonically increasing number. All serial
2418 * numbers are defined to be initialized at the start of the
2419 * association to the same value as the Initial TSN.
2420 */
2421 asoc->peer.addip_serial = asoc->peer.i.initial_tsn - 1;
2422 return 1;
2423
2424 clean_up:
2425 /* Release the transport structures. */
2426 list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
2427 transport = list_entry(pos, struct sctp_transport, transports);
2428 if (transport->state != SCTP_ACTIVE)
2429 sctp_assoc_rm_peer(asoc, transport);
2430 }
2431
2432 nomem:
2433 return 0;
2434 }
2435
2436
2437 /* Update asoc with the option described in param.
2438 *
2439 * RFC2960 3.3.2.1 Optional/Variable Length Parameters in INIT
2440 *
2441 * asoc is the association to update.
2442 * param is the variable length parameter to use for update.
2443 * cid tells us if this is an INIT, INIT ACK or COOKIE ECHO.
2444 * If the current packet is an INIT we want to minimize the amount of
2445 * work we do. In particular, we should not build transport
2446 * structures for the addresses.
2447 */
2448 static int sctp_process_param(struct sctp_association *asoc,
2449 union sctp_params param,
2450 const union sctp_addr *peer_addr,
2451 gfp_t gfp)
2452 {
2453 union sctp_addr addr;
2454 int i;
2455 __u16 sat;
2456 int retval = 1;
2457 sctp_scope_t scope;
2458 time_t stale;
2459 struct sctp_af *af;
2460 union sctp_addr_param *addr_param;
2461 struct sctp_transport *t;
2462
2463 /* We maintain all INIT parameters in network byte order all the
2464 * time. This allows us to not worry about whether the parameters
2465 * came from a fresh INIT, and INIT ACK, or were stored in a cookie.
2466 */
2467 switch (param.p->type) {
2468 case SCTP_PARAM_IPV6_ADDRESS:
2469 if (PF_INET6 != asoc->base.sk->sk_family)
2470 break;
2471 goto do_addr_param;
2472
2473 case SCTP_PARAM_IPV4_ADDRESS:
2474 /* v4 addresses are not allowed on v6-only socket */
2475 if (ipv6_only_sock(asoc->base.sk))
2476 break;
2477 do_addr_param:
2478 af = sctp_get_af_specific(param_type2af(param.p->type));
2479 af->from_addr_param(&addr, param.addr, htons(asoc->peer.port), 0);
2480 scope = sctp_scope(peer_addr);
2481 if (sctp_in_scope(&addr, scope))
2482 if (!sctp_assoc_add_peer(asoc, &addr, gfp, SCTP_UNCONFIRMED))
2483 return 0;
2484 break;
2485
2486 case SCTP_PARAM_COOKIE_PRESERVATIVE:
2487 if (!sctp_cookie_preserve_enable)
2488 break;
2489
2490 stale = ntohl(param.life->lifespan_increment);
2491
2492 /* Suggested Cookie Life span increment's unit is msec,
2493 * (1/1000sec).
2494 */
2495 asoc->cookie_life.tv_sec += stale / 1000;
2496 asoc->cookie_life.tv_usec += (stale % 1000) * 1000;
2497 break;
2498
2499 case SCTP_PARAM_HOST_NAME_ADDRESS:
2500 SCTP_DEBUG_PRINTK("unimplemented SCTP_HOST_NAME_ADDRESS\n");
2501 break;
2502
2503 case SCTP_PARAM_SUPPORTED_ADDRESS_TYPES:
2504 /* Turn off the default values first so we'll know which
2505 * ones are really set by the peer.
2506 */
2507 asoc->peer.ipv4_address = 0;
2508 asoc->peer.ipv6_address = 0;
2509
2510 /* Assume that peer supports the address family
2511 * by which it sends a packet.
2512 */
2513 if (peer_addr->sa.sa_family == AF_INET6)
2514 asoc->peer.ipv6_address = 1;
2515 else if (peer_addr->sa.sa_family == AF_INET)
2516 asoc->peer.ipv4_address = 1;
2517
2518 /* Cycle through address types; avoid divide by 0. */
2519 sat = ntohs(param.p->length) - sizeof(sctp_paramhdr_t);
2520 if (sat)
2521 sat /= sizeof(__u16);
2522
2523 for (i = 0; i < sat; ++i) {
2524 switch (param.sat->types[i]) {
2525 case SCTP_PARAM_IPV4_ADDRESS:
2526 asoc->peer.ipv4_address = 1;
2527 break;
2528
2529 case SCTP_PARAM_IPV6_ADDRESS:
2530 if (PF_INET6 == asoc->base.sk->sk_family)
2531 asoc->peer.ipv6_address = 1;
2532 break;
2533
2534 case SCTP_PARAM_HOST_NAME_ADDRESS:
2535 asoc->peer.hostname_address = 1;
2536 break;
2537
2538 default: /* Just ignore anything else. */
2539 break;
2540 }
2541 }
2542 break;
2543
2544 case SCTP_PARAM_STATE_COOKIE:
2545 asoc->peer.cookie_len =
2546 ntohs(param.p->length) - sizeof(sctp_paramhdr_t);
2547 asoc->peer.cookie = param.cookie->body;
2548 break;
2549
2550 case SCTP_PARAM_HEARTBEAT_INFO:
2551 /* Would be odd to receive, but it causes no problems. */
2552 break;
2553
2554 case SCTP_PARAM_UNRECOGNIZED_PARAMETERS:
2555 /* Rejected during verify stage. */
2556 break;
2557
2558 case SCTP_PARAM_ECN_CAPABLE:
2559 asoc->peer.ecn_capable = 1;
2560 break;
2561
2562 case SCTP_PARAM_ADAPTATION_LAYER_IND:
2563 asoc->peer.adaptation_ind = ntohl(param.aind->adaptation_ind);
2564 break;
2565
2566 case SCTP_PARAM_SET_PRIMARY:
2567 if (!sctp_addip_enable)
2568 goto fall_through;
2569
2570 addr_param = param.v + sizeof(sctp_addip_param_t);
2571
2572 af = sctp_get_af_specific(param_type2af(param.p->type));
2573 af->from_addr_param(&addr, addr_param,
2574 htons(asoc->peer.port), 0);
2575
2576 /* if the address is invalid, we can't process it.
2577 * XXX: see spec for what to do.
2578 */
2579 if (!af->addr_valid(&addr, NULL, NULL))
2580 break;
2581
2582 t = sctp_assoc_lookup_paddr(asoc, &addr);
2583 if (!t)
2584 break;
2585
2586 sctp_assoc_set_primary(asoc, t);
2587 break;
2588
2589 case SCTP_PARAM_SUPPORTED_EXT:
2590 sctp_process_ext_param(asoc, param);
2591 break;
2592
2593 case SCTP_PARAM_FWD_TSN_SUPPORT:
2594 if (sctp_prsctp_enable) {
2595 asoc->peer.prsctp_capable = 1;
2596 break;
2597 }
2598 /* Fall Through */
2599 goto fall_through;
2600
2601 case SCTP_PARAM_RANDOM:
2602 if (!sctp_auth_enable)
2603 goto fall_through;
2604
2605 /* Save peer's random parameter */
2606 asoc->peer.peer_random = kmemdup(param.p,
2607 ntohs(param.p->length), gfp);
2608 if (!asoc->peer.peer_random) {
2609 retval = 0;
2610 break;
2611 }
2612 break;
2613
2614 case SCTP_PARAM_HMAC_ALGO:
2615 if (!sctp_auth_enable)
2616 goto fall_through;
2617
2618 /* Save peer's HMAC list */
2619 asoc->peer.peer_hmacs = kmemdup(param.p,
2620 ntohs(param.p->length), gfp);
2621 if (!asoc->peer.peer_hmacs) {
2622 retval = 0;
2623 break;
2624 }
2625
2626 /* Set the default HMAC the peer requested*/
2627 sctp_auth_asoc_set_default_hmac(asoc, param.hmac_algo);
2628 break;
2629
2630 case SCTP_PARAM_CHUNKS:
2631 if (!sctp_auth_enable)
2632 goto fall_through;
2633
2634 asoc->peer.peer_chunks = kmemdup(param.p,
2635 ntohs(param.p->length), gfp);
2636 if (!asoc->peer.peer_chunks)
2637 retval = 0;
2638 break;
2639 fall_through:
2640 default:
2641 /* Any unrecognized parameters should have been caught
2642 * and handled by sctp_verify_param() which should be
2643 * called prior to this routine. Simply log the error
2644 * here.
2645 */
2646 SCTP_DEBUG_PRINTK("Ignoring param: %d for association %p.\n",
2647 ntohs(param.p->type), asoc);
2648 break;
2649 }
2650
2651 return retval;
2652 }
2653
2654 /* Select a new verification tag. */
2655 __u32 sctp_generate_tag(const struct sctp_endpoint *ep)
2656 {
2657 /* I believe that this random number generator complies with RFC1750.
2658 * A tag of 0 is reserved for special cases (e.g. INIT).
2659 */
2660 __u32 x;
2661
2662 do {
2663 get_random_bytes(&x, sizeof(__u32));
2664 } while (x == 0);
2665
2666 return x;
2667 }
2668
2669 /* Select an initial TSN to send during startup. */
2670 __u32 sctp_generate_tsn(const struct sctp_endpoint *ep)
2671 {
2672 __u32 retval;
2673
2674 get_random_bytes(&retval, sizeof(__u32));
2675 return retval;
2676 }
2677
2678 /*
2679 * ADDIP 3.1.1 Address Configuration Change Chunk (ASCONF)
2680 * 0 1 2 3
2681 * 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
2682 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2683 * | Type = 0xC1 | Chunk Flags | Chunk Length |
2684 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2685 * | Serial Number |
2686 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2687 * | Address Parameter |
2688 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2689 * | ASCONF Parameter #1 |
2690 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2691 * \ \
2692 * / .... /
2693 * \ \
2694 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2695 * | ASCONF Parameter #N |
2696 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2697 *
2698 * Address Parameter and other parameter will not be wrapped in this function
2699 */
2700 static struct sctp_chunk *sctp_make_asconf(struct sctp_association *asoc,
2701 union sctp_addr *addr,
2702 int vparam_len)
2703 {
2704 sctp_addiphdr_t asconf;
2705 struct sctp_chunk *retval;
2706 int length = sizeof(asconf) + vparam_len;
2707 union sctp_addr_param addrparam;
2708 int addrlen;
2709 struct sctp_af *af = sctp_get_af_specific(addr->v4.sin_family);
2710
2711 addrlen = af->to_addr_param(addr, &addrparam);
2712 if (!addrlen)
2713 return NULL;
2714 length += addrlen;
2715
2716 /* Create the chunk. */
2717 retval = sctp_make_chunk(asoc, SCTP_CID_ASCONF, 0, length);
2718 if (!retval)
2719 return NULL;
2720
2721 asconf.serial = htonl(asoc->addip_serial++);
2722
2723 retval->subh.addip_hdr =
2724 sctp_addto_chunk(retval, sizeof(asconf), &asconf);
2725 retval->param_hdr.v =
2726 sctp_addto_chunk(retval, addrlen, &addrparam);
2727
2728 return retval;
2729 }
2730
2731 /* ADDIP
2732 * 3.2.1 Add IP Address
2733 * 0 1 2 3
2734 * 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
2735 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2736 * | Type = 0xC001 | Length = Variable |
2737 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2738 * | ASCONF-Request Correlation ID |
2739 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2740 * | Address Parameter |
2741 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2742 *
2743 * 3.2.2 Delete IP Address
2744 * 0 1 2 3
2745 * 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
2746 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2747 * | Type = 0xC002 | Length = Variable |
2748 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2749 * | ASCONF-Request Correlation ID |
2750 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2751 * | Address Parameter |
2752 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2753 *
2754 */
2755 struct sctp_chunk *sctp_make_asconf_update_ip(struct sctp_association *asoc,
2756 union sctp_addr *laddr,
2757 struct sockaddr *addrs,
2758 int addrcnt,
2759 __be16 flags)
2760 {
2761 sctp_addip_param_t param;
2762 struct sctp_chunk *retval;
2763 union sctp_addr_param addr_param;
2764 union sctp_addr *addr;
2765 void *addr_buf;
2766 struct sctp_af *af;
2767 int paramlen = sizeof(param);
2768 int addr_param_len = 0;
2769 int totallen = 0;
2770 int i;
2771 int del_pickup = 0;
2772
2773 /* Get total length of all the address parameters. */
2774 addr_buf = addrs;
2775 for (i = 0; i < addrcnt; i++) {
2776 addr = addr_buf;
2777 af = sctp_get_af_specific(addr->v4.sin_family);
2778 addr_param_len = af->to_addr_param(addr, &addr_param);
2779
2780 totallen += paramlen;
2781 totallen += addr_param_len;
2782
2783 addr_buf += af->sockaddr_len;
2784 if (asoc->asconf_addr_del_pending && !del_pickup) {
2785 /* reuse the parameter length from the same scope one */
2786 totallen += paramlen;
2787 totallen += addr_param_len;
2788 del_pickup = 1;
2789 SCTP_DEBUG_PRINTK("mkasconf_update_ip: picked same-scope del_pending addr, totallen for all addresses is %d\n", totallen);
2790 }
2791 }
2792
2793 /* Create an asconf chunk with the required length. */
2794 retval = sctp_make_asconf(asoc, laddr, totallen);
2795 if (!retval)
2796 return NULL;
2797
2798 /* Add the address parameters to the asconf chunk. */
2799 addr_buf = addrs;
2800 for (i = 0; i < addrcnt; i++) {
2801 addr = addr_buf;
2802 af = sctp_get_af_specific(addr->v4.sin_family);
2803 addr_param_len = af->to_addr_param(addr, &addr_param);
2804 param.param_hdr.type = flags;
2805 param.param_hdr.length = htons(paramlen + addr_param_len);
2806 param.crr_id = i;
2807
2808 sctp_addto_chunk(retval, paramlen, &param);
2809 sctp_addto_chunk(retval, addr_param_len, &addr_param);
2810
2811 addr_buf += af->sockaddr_len;
2812 }
2813 if (flags == SCTP_PARAM_ADD_IP && del_pickup) {
2814 addr = asoc->asconf_addr_del_pending;
2815 af = sctp_get_af_specific(addr->v4.sin_family);
2816 addr_param_len = af->to_addr_param(addr, &addr_param);
2817 param.param_hdr.type = SCTP_PARAM_DEL_IP;
2818 param.param_hdr.length = htons(paramlen + addr_param_len);
2819 param.crr_id = i;
2820
2821 sctp_addto_chunk(retval, paramlen, &param);
2822 sctp_addto_chunk(retval, addr_param_len, &addr_param);
2823 }
2824 return retval;
2825 }
2826
2827 /* ADDIP
2828 * 3.2.4 Set Primary IP Address
2829 * 0 1 2 3
2830 * 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
2831 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2832 * | Type =0xC004 | Length = Variable |
2833 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2834 * | ASCONF-Request Correlation ID |
2835 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2836 * | Address Parameter |
2837 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2838 *
2839 * Create an ASCONF chunk with Set Primary IP address parameter.
2840 */
2841 struct sctp_chunk *sctp_make_asconf_set_prim(struct sctp_association *asoc,
2842 union sctp_addr *addr)
2843 {
2844 sctp_addip_param_t param;
2845 struct sctp_chunk *retval;
2846 int len = sizeof(param);
2847 union sctp_addr_param addrparam;
2848 int addrlen;
2849 struct sctp_af *af = sctp_get_af_specific(addr->v4.sin_family);
2850
2851 addrlen = af->to_addr_param(addr, &addrparam);
2852 if (!addrlen)
2853 return NULL;
2854 len += addrlen;
2855
2856 /* Create the chunk and make asconf header. */
2857 retval = sctp_make_asconf(asoc, addr, len);
2858 if (!retval)
2859 return NULL;
2860
2861 param.param_hdr.type = SCTP_PARAM_SET_PRIMARY;
2862 param.param_hdr.length = htons(len);
2863 param.crr_id = 0;
2864
2865 sctp_addto_chunk(retval, sizeof(param), &param);
2866 sctp_addto_chunk(retval, addrlen, &addrparam);
2867
2868 return retval;
2869 }
2870
2871 /* ADDIP 3.1.2 Address Configuration Acknowledgement Chunk (ASCONF-ACK)
2872 * 0 1 2 3
2873 * 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
2874 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2875 * | Type = 0x80 | Chunk Flags | Chunk Length |
2876 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2877 * | Serial Number |
2878 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2879 * | ASCONF Parameter Response#1 |
2880 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2881 * \ \
2882 * / .... /
2883 * \ \
2884 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2885 * | ASCONF Parameter Response#N |
2886 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2887 *
2888 * Create an ASCONF_ACK chunk with enough space for the parameter responses.
2889 */
2890 static struct sctp_chunk *sctp_make_asconf_ack(const struct sctp_association *asoc,
2891 __u32 serial, int vparam_len)
2892 {
2893 sctp_addiphdr_t asconf;
2894 struct sctp_chunk *retval;
2895 int length = sizeof(asconf) + vparam_len;
2896
2897 /* Create the chunk. */
2898 retval = sctp_make_chunk(asoc, SCTP_CID_ASCONF_ACK, 0, length);
2899 if (!retval)
2900 return NULL;
2901
2902 asconf.serial = htonl(serial);
2903
2904 retval->subh.addip_hdr =
2905 sctp_addto_chunk(retval, sizeof(asconf), &asconf);
2906
2907 return retval;
2908 }
2909
2910 /* Add response parameters to an ASCONF_ACK chunk. */
2911 static void sctp_add_asconf_response(struct sctp_chunk *chunk, __be32 crr_id,
2912 __be16 err_code, sctp_addip_param_t *asconf_param)
2913 {
2914 sctp_addip_param_t ack_param;
2915 sctp_errhdr_t err_param;
2916 int asconf_param_len = 0;
2917 int err_param_len = 0;
2918 __be16 response_type;
2919
2920 if (SCTP_ERROR_NO_ERROR == err_code) {
2921 response_type = SCTP_PARAM_SUCCESS_REPORT;
2922 } else {
2923 response_type = SCTP_PARAM_ERR_CAUSE;
2924 err_param_len = sizeof(err_param);
2925 if (asconf_param)
2926 asconf_param_len =
2927 ntohs(asconf_param->param_hdr.length);
2928 }
2929
2930 /* Add Success Indication or Error Cause Indication parameter. */
2931 ack_param.param_hdr.type = response_type;
2932 ack_param.param_hdr.length = htons(sizeof(ack_param) +
2933 err_param_len +
2934 asconf_param_len);
2935 ack_param.crr_id = crr_id;
2936 sctp_addto_chunk(chunk, sizeof(ack_param), &ack_param);
2937
2938 if (SCTP_ERROR_NO_ERROR == err_code)
2939 return;
2940
2941 /* Add Error Cause parameter. */
2942 err_param.cause = err_code;
2943 err_param.length = htons(err_param_len + asconf_param_len);
2944 sctp_addto_chunk(chunk, err_param_len, &err_param);
2945
2946 /* Add the failed TLV copied from ASCONF chunk. */
2947 if (asconf_param)
2948 sctp_addto_chunk(chunk, asconf_param_len, asconf_param);
2949 }
2950
2951 /* Process a asconf parameter. */
2952 static __be16 sctp_process_asconf_param(struct sctp_association *asoc,
2953 struct sctp_chunk *asconf,
2954 sctp_addip_param_t *asconf_param)
2955 {
2956 struct sctp_transport *peer;
2957 struct sctp_af *af;
2958 union sctp_addr addr;
2959 union sctp_addr_param *addr_param;
2960
2961 addr_param = (void *)asconf_param + sizeof(sctp_addip_param_t);
2962
2963 if (asconf_param->param_hdr.type != SCTP_PARAM_ADD_IP &&
2964 asconf_param->param_hdr.type != SCTP_PARAM_DEL_IP &&
2965 asconf_param->param_hdr.type != SCTP_PARAM_SET_PRIMARY)
2966 return SCTP_ERROR_UNKNOWN_PARAM;
2967
2968 switch (addr_param->p.type) {
2969 case SCTP_PARAM_IPV6_ADDRESS:
2970 if (!asoc->peer.ipv6_address)
2971 return SCTP_ERROR_DNS_FAILED;
2972 break;
2973 case SCTP_PARAM_IPV4_ADDRESS:
2974 if (!asoc->peer.ipv4_address)
2975 return SCTP_ERROR_DNS_FAILED;
2976 break;
2977 default:
2978 return SCTP_ERROR_DNS_FAILED;
2979 }
2980
2981 af = sctp_get_af_specific(param_type2af(addr_param->p.type));
2982 if (unlikely(!af))
2983 return SCTP_ERROR_DNS_FAILED;
2984
2985 af->from_addr_param(&addr, addr_param, htons(asoc->peer.port), 0);
2986
2987 /* ADDIP 4.2.1 This parameter MUST NOT contain a broadcast
2988 * or multicast address.
2989 * (note: wildcard is permitted and requires special handling so
2990 * make sure we check for that)
2991 */
2992 if (!af->is_any(&addr) && !af->addr_valid(&addr, NULL, asconf->skb))
2993 return SCTP_ERROR_DNS_FAILED;
2994
2995 switch (asconf_param->param_hdr.type) {
2996 case SCTP_PARAM_ADD_IP:
2997 /* Section 4.2.1:
2998 * If the address 0.0.0.0 or ::0 is provided, the source
2999 * address of the packet MUST be added.
3000 */
3001 if (af->is_any(&addr))
3002 memcpy(&addr, &asconf->source, sizeof(addr));
3003
3004 /* ADDIP 4.3 D9) If an endpoint receives an ADD IP address
3005 * request and does not have the local resources to add this
3006 * new address to the association, it MUST return an Error
3007 * Cause TLV set to the new error code 'Operation Refused
3008 * Due to Resource Shortage'.
3009 */
3010
3011 peer = sctp_assoc_add_peer(asoc, &addr, GFP_ATOMIC, SCTP_UNCONFIRMED);
3012 if (!peer)
3013 return SCTP_ERROR_RSRC_LOW;
3014
3015 /* Start the heartbeat timer. */
3016 if (!mod_timer(&peer->hb_timer, sctp_transport_timeout(peer)))
3017 sctp_transport_hold(peer);
3018 asoc->new_transport = peer;
3019 break;
3020 case SCTP_PARAM_DEL_IP:
3021 /* ADDIP 4.3 D7) If a request is received to delete the
3022 * last remaining IP address of a peer endpoint, the receiver
3023 * MUST send an Error Cause TLV with the error cause set to the
3024 * new error code 'Request to Delete Last Remaining IP Address'.
3025 */
3026 if (asoc->peer.transport_count == 1)
3027 return SCTP_ERROR_DEL_LAST_IP;
3028
3029 /* ADDIP 4.3 D8) If a request is received to delete an IP
3030 * address which is also the source address of the IP packet
3031 * which contained the ASCONF chunk, the receiver MUST reject
3032 * this request. To reject the request the receiver MUST send
3033 * an Error Cause TLV set to the new error code 'Request to
3034 * Delete Source IP Address'
3035 */
3036 if (sctp_cmp_addr_exact(&asconf->source, &addr))
3037 return SCTP_ERROR_DEL_SRC_IP;
3038
3039 /* Section 4.2.2
3040 * If the address 0.0.0.0 or ::0 is provided, all
3041 * addresses of the peer except the source address of the
3042 * packet MUST be deleted.
3043 */
3044 if (af->is_any(&addr)) {
3045 sctp_assoc_set_primary(asoc, asconf->transport);
3046 sctp_assoc_del_nonprimary_peers(asoc,
3047 asconf->transport);
3048 } else
3049 sctp_assoc_del_peer(asoc, &addr);
3050 break;
3051 case SCTP_PARAM_SET_PRIMARY:
3052 /* ADDIP Section 4.2.4
3053 * If the address 0.0.0.0 or ::0 is provided, the receiver
3054 * MAY mark the source address of the packet as its
3055 * primary.
3056 */
3057 if (af->is_any(&addr))
3058 memcpy(&addr.v4, sctp_source(asconf), sizeof(addr));
3059
3060 peer = sctp_assoc_lookup_paddr(asoc, &addr);
3061 if (!peer)
3062 return SCTP_ERROR_DNS_FAILED;
3063
3064 sctp_assoc_set_primary(asoc, peer);
3065 break;
3066 }
3067
3068 return SCTP_ERROR_NO_ERROR;
3069 }
3070
3071 /* Verify the ASCONF packet before we process it. */
3072 int sctp_verify_asconf(const struct sctp_association *asoc,
3073 struct sctp_paramhdr *param_hdr, void *chunk_end,
3074 struct sctp_paramhdr **errp) {
3075 sctp_addip_param_t *asconf_param;
3076 union sctp_params param;
3077 int length, plen;
3078
3079 param.v = (sctp_paramhdr_t *) param_hdr;
3080 while (param.v <= chunk_end - sizeof(sctp_paramhdr_t)) {
3081 length = ntohs(param.p->length);
3082 *errp = param.p;
3083
3084 if (param.v > chunk_end - length ||
3085 length < sizeof(sctp_paramhdr_t))
3086 return 0;
3087
3088 switch (param.p->type) {
3089 case SCTP_PARAM_ADD_IP:
3090 case SCTP_PARAM_DEL_IP:
3091 case SCTP_PARAM_SET_PRIMARY:
3092 asconf_param = (sctp_addip_param_t *)param.v;
3093 plen = ntohs(asconf_param->param_hdr.length);
3094 if (plen < sizeof(sctp_addip_param_t) +
3095 sizeof(sctp_paramhdr_t))
3096 return 0;
3097 break;
3098 case SCTP_PARAM_SUCCESS_REPORT:
3099 case SCTP_PARAM_ADAPTATION_LAYER_IND:
3100 if (length != sizeof(sctp_addip_param_t))
3101 return 0;
3102
3103 break;
3104 default:
3105 break;
3106 }
3107
3108 param.v += WORD_ROUND(length);
3109 }
3110
3111 if (param.v != chunk_end)
3112 return 0;
3113
3114 return 1;
3115 }
3116
3117 /* Process an incoming ASCONF chunk with the next expected serial no. and
3118 * return an ASCONF_ACK chunk to be sent in response.
3119 */
3120 struct sctp_chunk *sctp_process_asconf(struct sctp_association *asoc,
3121 struct sctp_chunk *asconf)
3122 {
3123 sctp_addiphdr_t *hdr;
3124 union sctp_addr_param *addr_param;
3125 sctp_addip_param_t *asconf_param;
3126 struct sctp_chunk *asconf_ack;
3127
3128 __be16 err_code;
3129 int length = 0;
3130 int chunk_len;
3131 __u32 serial;
3132 int all_param_pass = 1;
3133
3134 chunk_len = ntohs(asconf->chunk_hdr->length) - sizeof(sctp_chunkhdr_t);
3135 hdr = (sctp_addiphdr_t *)asconf->skb->data;
3136 serial = ntohl(hdr->serial);
3137
3138 /* Skip the addiphdr and store a pointer to address parameter. */
3139 length = sizeof(sctp_addiphdr_t);
3140 addr_param = (union sctp_addr_param *)(asconf->skb->data + length);
3141 chunk_len -= length;
3142
3143 /* Skip the address parameter and store a pointer to the first
3144 * asconf parameter.
3145 */
3146 length = ntohs(addr_param->p.length);
3147 asconf_param = (void *)addr_param + length;
3148 chunk_len -= length;
3149
3150 /* create an ASCONF_ACK chunk.
3151 * Based on the definitions of parameters, we know that the size of
3152 * ASCONF_ACK parameters are less than or equal to the fourfold of ASCONF
3153 * parameters.
3154 */
3155 asconf_ack = sctp_make_asconf_ack(asoc, serial, chunk_len * 4);
3156 if (!asconf_ack)
3157 goto done;
3158
3159 /* Process the TLVs contained within the ASCONF chunk. */
3160 while (chunk_len > 0) {
3161 err_code = sctp_process_asconf_param(asoc, asconf,
3162 asconf_param);
3163 /* ADDIP 4.1 A7)
3164 * If an error response is received for a TLV parameter,
3165 * all TLVs with no response before the failed TLV are
3166 * considered successful if not reported. All TLVs after
3167 * the failed response are considered unsuccessful unless
3168 * a specific success indication is present for the parameter.
3169 */
3170 if (SCTP_ERROR_NO_ERROR != err_code)
3171 all_param_pass = 0;
3172
3173 if (!all_param_pass)
3174 sctp_add_asconf_response(asconf_ack,
3175 asconf_param->crr_id, err_code,
3176 asconf_param);
3177
3178 /* ADDIP 4.3 D11) When an endpoint receiving an ASCONF to add
3179 * an IP address sends an 'Out of Resource' in its response, it
3180 * MUST also fail any subsequent add or delete requests bundled
3181 * in the ASCONF.
3182 */
3183 if (SCTP_ERROR_RSRC_LOW == err_code)
3184 goto done;
3185
3186 /* Move to the next ASCONF param. */
3187 length = ntohs(asconf_param->param_hdr.length);
3188 asconf_param = (void *)asconf_param + length;
3189 chunk_len -= length;
3190 }
3191
3192 done:
3193 asoc->peer.addip_serial++;
3194
3195 /* If we are sending a new ASCONF_ACK hold a reference to it in assoc
3196 * after freeing the reference to old asconf ack if any.
3197 */
3198 if (asconf_ack) {
3199 sctp_chunk_hold(asconf_ack);
3200 list_add_tail(&asconf_ack->transmitted_list,
3201 &asoc->asconf_ack_list);
3202 }
3203
3204 return asconf_ack;
3205 }
3206
3207 /* Process a asconf parameter that is successfully acked. */
3208 static void sctp_asconf_param_success(struct sctp_association *asoc,
3209 sctp_addip_param_t *asconf_param)
3210 {
3211 struct sctp_af *af;
3212 union sctp_addr addr;
3213 struct sctp_bind_addr *bp = &asoc->base.bind_addr;
3214 union sctp_addr_param *addr_param;
3215 struct sctp_transport *transport;
3216 struct sctp_sockaddr_entry *saddr;
3217
3218 addr_param = (void *)asconf_param + sizeof(sctp_addip_param_t);
3219
3220 /* We have checked the packet before, so we do not check again. */
3221 af = sctp_get_af_specific(param_type2af(addr_param->p.type));
3222 af->from_addr_param(&addr, addr_param, htons(bp->port), 0);
3223
3224 switch (asconf_param->param_hdr.type) {
3225 case SCTP_PARAM_ADD_IP:
3226 /* This is always done in BH context with a socket lock
3227 * held, so the list can not change.
3228 */
3229 local_bh_disable();
3230 list_for_each_entry(saddr, &bp->address_list, list) {
3231 if (sctp_cmp_addr_exact(&saddr->a, &addr))
3232 saddr->state = SCTP_ADDR_SRC;
3233 }
3234 local_bh_enable();
3235 list_for_each_entry(transport, &asoc->peer.transport_addr_list,
3236 transports) {
3237 dst_release(transport->dst);
3238 transport->dst = NULL;
3239 }
3240 break;
3241 case SCTP_PARAM_DEL_IP:
3242 local_bh_disable();
3243 sctp_del_bind_addr(bp, &addr);
3244 if (asoc->asconf_addr_del_pending != NULL &&
3245 sctp_cmp_addr_exact(asoc->asconf_addr_del_pending, &addr)) {
3246 kfree(asoc->asconf_addr_del_pending);
3247 asoc->asconf_addr_del_pending = NULL;
3248 }
3249 local_bh_enable();
3250 list_for_each_entry(transport, &asoc->peer.transport_addr_list,
3251 transports) {
3252 dst_release(transport->dst);
3253 transport->dst = NULL;
3254 }
3255 break;
3256 default:
3257 break;
3258 }
3259 }
3260
3261 /* Get the corresponding ASCONF response error code from the ASCONF_ACK chunk
3262 * for the given asconf parameter. If there is no response for this parameter,
3263 * return the error code based on the third argument 'no_err'.
3264 * ADDIP 4.1
3265 * A7) If an error response is received for a TLV parameter, all TLVs with no
3266 * response before the failed TLV are considered successful if not reported.
3267 * All TLVs after the failed response are considered unsuccessful unless a
3268 * specific success indication is present for the parameter.
3269 */
3270 static __be16 sctp_get_asconf_response(struct sctp_chunk *asconf_ack,
3271 sctp_addip_param_t *asconf_param,
3272 int no_err)
3273 {
3274 sctp_addip_param_t *asconf_ack_param;
3275 sctp_errhdr_t *err_param;
3276 int length;
3277 int asconf_ack_len;
3278 __be16 err_code;
3279
3280 if (no_err)
3281 err_code = SCTP_ERROR_NO_ERROR;
3282 else
3283 err_code = SCTP_ERROR_REQ_REFUSED;
3284
3285 asconf_ack_len = ntohs(asconf_ack->chunk_hdr->length) -
3286 sizeof(sctp_chunkhdr_t);
3287
3288 /* Skip the addiphdr from the asconf_ack chunk and store a pointer to
3289 * the first asconf_ack parameter.
3290 */
3291 length = sizeof(sctp_addiphdr_t);
3292 asconf_ack_param = (sctp_addip_param_t *)(asconf_ack->skb->data +
3293 length);
3294 asconf_ack_len -= length;
3295
3296 while (asconf_ack_len > 0) {
3297 if (asconf_ack_param->crr_id == asconf_param->crr_id) {
3298 switch(asconf_ack_param->param_hdr.type) {
3299 case SCTP_PARAM_SUCCESS_REPORT:
3300 return SCTP_ERROR_NO_ERROR;
3301 case SCTP_PARAM_ERR_CAUSE:
3302 length = sizeof(sctp_addip_param_t);
3303 err_param = (void *)asconf_ack_param + length;
3304 asconf_ack_len -= length;
3305 if (asconf_ack_len > 0)
3306 return err_param->cause;
3307 else
3308 return SCTP_ERROR_INV_PARAM;
3309 break;
3310 default:
3311 return SCTP_ERROR_INV_PARAM;
3312 }
3313 }
3314
3315 length = ntohs(asconf_ack_param->param_hdr.length);
3316 asconf_ack_param = (void *)asconf_ack_param + length;
3317 asconf_ack_len -= length;
3318 }
3319
3320 return err_code;
3321 }
3322
3323 /* Process an incoming ASCONF_ACK chunk against the cached last ASCONF chunk. */
3324 int sctp_process_asconf_ack(struct sctp_association *asoc,
3325 struct sctp_chunk *asconf_ack)
3326 {
3327 struct sctp_chunk *asconf = asoc->addip_last_asconf;
3328 union sctp_addr_param *addr_param;
3329 sctp_addip_param_t *asconf_param;
3330 int length = 0;
3331 int asconf_len = asconf->skb->len;
3332 int all_param_pass = 0;
3333 int no_err = 1;
3334 int retval = 0;
3335 __be16 err_code = SCTP_ERROR_NO_ERROR;
3336
3337 /* Skip the chunkhdr and addiphdr from the last asconf sent and store
3338 * a pointer to address parameter.
3339 */
3340 length = sizeof(sctp_addip_chunk_t);
3341 addr_param = (union sctp_addr_param *)(asconf->skb->data + length);
3342 asconf_len -= length;
3343
3344 /* Skip the address parameter in the last asconf sent and store a
3345 * pointer to the first asconf parameter.
3346 */
3347 length = ntohs(addr_param->p.length);
3348 asconf_param = (void *)addr_param + length;
3349 asconf_len -= length;
3350
3351 /* ADDIP 4.1
3352 * A8) If there is no response(s) to specific TLV parameter(s), and no
3353 * failures are indicated, then all request(s) are considered
3354 * successful.
3355 */
3356 if (asconf_ack->skb->len == sizeof(sctp_addiphdr_t))
3357 all_param_pass = 1;
3358
3359 /* Process the TLVs contained in the last sent ASCONF chunk. */
3360 while (asconf_len > 0) {
3361 if (all_param_pass)
3362 err_code = SCTP_ERROR_NO_ERROR;
3363 else {
3364 err_code = sctp_get_asconf_response(asconf_ack,
3365 asconf_param,
3366 no_err);
3367 if (no_err && (SCTP_ERROR_NO_ERROR != err_code))
3368 no_err = 0;
3369 }
3370
3371 switch (err_code) {
3372 case SCTP_ERROR_NO_ERROR:
3373 sctp_asconf_param_success(asoc, asconf_param);
3374 break;
3375
3376 case SCTP_ERROR_RSRC_LOW:
3377 retval = 1;
3378 break;
3379
3380 case SCTP_ERROR_UNKNOWN_PARAM:
3381 /* Disable sending this type of asconf parameter in
3382 * future.
3383 */
3384 asoc->peer.addip_disabled_mask |=
3385 asconf_param->param_hdr.type;
3386 break;
3387
3388 case SCTP_ERROR_REQ_REFUSED:
3389 case SCTP_ERROR_DEL_LAST_IP:
3390 case SCTP_ERROR_DEL_SRC_IP:
3391 default:
3392 break;
3393 }
3394
3395 /* Skip the processed asconf parameter and move to the next
3396 * one.
3397 */
3398 length = ntohs(asconf_param->param_hdr.length);
3399 asconf_param = (void *)asconf_param + length;
3400 asconf_len -= length;
3401 }
3402
3403 if (no_err && asoc->src_out_of_asoc_ok) {
3404 asoc->src_out_of_asoc_ok = 0;
3405 sctp_transport_immediate_rtx(asoc->peer.primary_path);
3406 }
3407
3408 /* Free the cached last sent asconf chunk. */
3409 list_del_init(&asconf->transmitted_list);
3410 sctp_chunk_free(asconf);
3411 asoc->addip_last_asconf = NULL;
3412
3413 return retval;
3414 }
3415
3416 /* Make a FWD TSN chunk. */
3417 struct sctp_chunk *sctp_make_fwdtsn(const struct sctp_association *asoc,
3418 __u32 new_cum_tsn, size_t nstreams,
3419 struct sctp_fwdtsn_skip *skiplist)
3420 {
3421 struct sctp_chunk *retval = NULL;
3422 struct sctp_fwdtsn_hdr ftsn_hdr;
3423 struct sctp_fwdtsn_skip skip;
3424 size_t hint;
3425 int i;
3426
3427 hint = (nstreams + 1) * sizeof(__u32);
3428
3429 retval = sctp_make_chunk(asoc, SCTP_CID_FWD_TSN, 0, hint);
3430
3431 if (!retval)
3432 return NULL;
3433
3434 ftsn_hdr.new_cum_tsn = htonl(new_cum_tsn);
3435 retval->subh.fwdtsn_hdr =
3436 sctp_addto_chunk(retval, sizeof(ftsn_hdr), &ftsn_hdr);
3437
3438 for (i = 0; i < nstreams; i++) {
3439 skip.stream = skiplist[i].stream;
3440 skip.ssn = skiplist[i].ssn;
3441 sctp_addto_chunk(retval, sizeof(skip), &skip);
3442 }
3443
3444 return retval;
3445 }
Linus' kernel tree