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scsi: fc: Export fc_bsg_jobdone and use it in FC drivers
[linux/fpc-iii.git] / net / sctp / sm_make_chunk.c
blob9e9690b7afe118636eb64751f9c58637be56c5e8
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, see
27 * <http://www.gnu.org/licenses/>.
28 *
29 * Please send any bug reports or fixes you make to the
30 * email address(es):
31 * lksctp developers <linux-sctp@vger.kernel.org>
32 *
33 * Written or modified by:
34 * La Monte H.P. Yarroll <piggy@acm.org>
35 * Karl Knutson <karl@athena.chicago.il.us>
36 * C. Robin <chris@hundredacre.ac.uk>
37 * Jon Grimm <jgrimm@us.ibm.com>
38 * Xingang Guo <xingang.guo@intel.com>
39 * Dajiang Zhang <dajiang.zhang@nokia.com>
40 * Sridhar Samudrala <sri@us.ibm.com>
41 * Daisy Chang <daisyc@us.ibm.com>
42 * Ardelle Fan <ardelle.fan@intel.com>
43 * Kevin Gao <kevin.gao@intel.com>
44 */
45
46 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
47
48 #include <crypto/hash.h>
49 #include <linux/types.h>
50 #include <linux/kernel.h>
51 #include <linux/ip.h>
52 #include <linux/ipv6.h>
53 #include <linux/net.h>
54 #include <linux/inet.h>
55 #include <linux/scatterlist.h>
56 #include <linux/slab.h>
57 #include <net/sock.h>
58
59 #include <linux/skbuff.h>
60 #include <linux/random.h> /* for get_random_bytes */
61 #include <net/sctp/sctp.h>
62 #include <net/sctp/sm.h>
63
64 static struct sctp_chunk *sctp_make_control(const struct sctp_association *asoc,
65 __u8 type, __u8 flags, int paylen,
66 gfp_t gfp);
67 static struct sctp_chunk *sctp_make_data(const struct sctp_association *asoc,
68 __u8 flags, int paylen, gfp_t gfp);
69 static struct sctp_chunk *_sctp_make_chunk(const struct sctp_association *asoc,
70 __u8 type, __u8 flags, int paylen,
71 gfp_t gfp);
72 static sctp_cookie_param_t *sctp_pack_cookie(const struct sctp_endpoint *ep,
73 const struct sctp_association *asoc,
74 const struct sctp_chunk *init_chunk,
75 int *cookie_len,
76 const __u8 *raw_addrs, int addrs_len);
77 static int sctp_process_param(struct sctp_association *asoc,
78 union sctp_params param,
79 const union sctp_addr *peer_addr,
80 gfp_t gfp);
81 static void *sctp_addto_param(struct sctp_chunk *chunk, int len,
82 const void *data);
83 static void *sctp_addto_chunk_fixed(struct sctp_chunk *, int len,
84 const void *data);
85
86 /* Control chunk destructor */
87 static void sctp_control_release_owner(struct sk_buff *skb)
88 {
89 /*TODO: do memory release */
90 }
91
92 static void sctp_control_set_owner_w(struct sctp_chunk *chunk)
93 {
94 struct sctp_association *asoc = chunk->asoc;
95 struct sk_buff *skb = chunk->skb;
96
97 /* TODO: properly account for control chunks.
98 * To do it right we'll need:
99 * 1) endpoint if association isn't known.
100 * 2) proper memory accounting.
101 *
102 * For now don't do anything for now.
103 */
104 skb->sk = asoc ? asoc->base.sk : NULL;
105 skb->destructor = sctp_control_release_owner;
106 }
107
108 /* What was the inbound interface for this chunk? */
109 int sctp_chunk_iif(const struct sctp_chunk *chunk)
110 {
111 struct sk_buff *skb = chunk->skb;
112
113 return SCTP_INPUT_CB(skb)->af->skb_iif(skb);
114 }
115
116 /* RFC 2960 3.3.2 Initiation (INIT) (1)
117 *
118 * Note 2: The ECN capable field is reserved for future use of
119 * Explicit Congestion Notification.
120 */
121 static const struct sctp_paramhdr ecap_param = {
122 SCTP_PARAM_ECN_CAPABLE,
123 cpu_to_be16(sizeof(struct sctp_paramhdr)),
124 };
125 static const struct sctp_paramhdr prsctp_param = {
126 SCTP_PARAM_FWD_TSN_SUPPORT,
127 cpu_to_be16(sizeof(struct sctp_paramhdr)),
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.
133 */
134 void sctp_init_cause(struct sctp_chunk *chunk, __be16 cause_code,
135 size_t paylen)
136 {
137 sctp_errhdr_t err;
138 __u16 len;
139
140 /* Cause code constants are now defined in network order. */
141 err.cause = cause_code;
142 len = sizeof(sctp_errhdr_t) + paylen;
143 err.length = htons(len);
144 chunk->subh.err_hdr = sctp_addto_chunk(chunk, sizeof(sctp_errhdr_t), &err);
145 }
146
147 /* A helper to initialize an op error inside a
148 * provided chunk, as most cause codes will be embedded inside an
149 * abort chunk. Differs from sctp_init_cause in that it won't oops
150 * if there isn't enough space in the op error chunk
151 */
152 static int sctp_init_cause_fixed(struct sctp_chunk *chunk, __be16 cause_code,
153 size_t paylen)
154 {
155 sctp_errhdr_t err;
156 __u16 len;
157
158 /* Cause code constants are now defined in network order. */
159 err.cause = cause_code;
160 len = sizeof(sctp_errhdr_t) + paylen;
161 err.length = htons(len);
162
163 if (skb_tailroom(chunk->skb) < len)
164 return -ENOSPC;
165 chunk->subh.err_hdr = sctp_addto_chunk_fixed(chunk,
166 sizeof(sctp_errhdr_t),
167 &err);
168 return 0;
169 }
170 /* 3.3.2 Initiation (INIT) (1)
171 *
172 * This chunk is used to initiate a SCTP association between two
173 * endpoints. The format of the INIT chunk is shown below:
174 *
175 * 0 1 2 3
176 * 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
177 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
178 * | Type = 1 | Chunk Flags | Chunk Length |
179 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
180 * | Initiate Tag |
181 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
182 * | Advertised Receiver Window Credit (a_rwnd) |
183 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
184 * | Number of Outbound Streams | Number of Inbound Streams |
185 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
186 * | Initial TSN |
187 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
188 * \ \
189 * / Optional/Variable-Length Parameters /
190 * \ \
191 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
192 *
193 *
194 * The INIT chunk contains the following parameters. Unless otherwise
195 * noted, each parameter MUST only be included once in the INIT chunk.
196 *
197 * Fixed Parameters Status
198 * ----------------------------------------------
199 * Initiate Tag Mandatory
200 * Advertised Receiver Window Credit Mandatory
201 * Number of Outbound Streams Mandatory
202 * Number of Inbound Streams Mandatory
203 * Initial TSN Mandatory
204 *
205 * Variable Parameters Status Type Value
206 * -------------------------------------------------------------
207 * IPv4 Address (Note 1) Optional 5
208 * IPv6 Address (Note 1) Optional 6
209 * Cookie Preservative Optional 9
210 * Reserved for ECN Capable (Note 2) Optional 32768 (0x8000)
211 * Host Name Address (Note 3) Optional 11
212 * Supported Address Types (Note 4) Optional 12
213 */
214 struct sctp_chunk *sctp_make_init(const struct sctp_association *asoc,
215 const struct sctp_bind_addr *bp,
216 gfp_t gfp, int vparam_len)
217 {
218 struct net *net = sock_net(asoc->base.sk);
219 struct sctp_endpoint *ep = asoc->ep;
220 sctp_inithdr_t init;
221 union sctp_params addrs;
222 size_t chunksize;
223 struct sctp_chunk *retval = NULL;
224 int num_types, addrs_len = 0;
225 struct sctp_sock *sp;
226 sctp_supported_addrs_param_t sat;
227 __be16 types[2];
228 sctp_adaptation_ind_param_t aiparam;
229 sctp_supported_ext_param_t ext_param;
230 int num_ext = 0;
231 __u8 extensions[3];
232 sctp_paramhdr_t *auth_chunks = NULL,
233 *auth_hmacs = NULL;
234
235 /* RFC 2960 3.3.2 Initiation (INIT) (1)
236 *
237 * Note 1: The INIT chunks can contain multiple addresses that
238 * can be IPv4 and/or IPv6 in any combination.
239 */
240 retval = NULL;
241
242 /* Convert the provided bind address list to raw format. */
243 addrs = sctp_bind_addrs_to_raw(bp, &addrs_len, gfp);
244
245 init.init_tag = htonl(asoc->c.my_vtag);
246 init.a_rwnd = htonl(asoc->rwnd);
247 init.num_outbound_streams = htons(asoc->c.sinit_num_ostreams);
248 init.num_inbound_streams = htons(asoc->c.sinit_max_instreams);
249 init.initial_tsn = htonl(asoc->c.initial_tsn);
250
251 /* How many address types are needed? */
252 sp = sctp_sk(asoc->base.sk);
253 num_types = sp->pf->supported_addrs(sp, types);
254
255 chunksize = sizeof(init) + addrs_len;
256 chunksize += SCTP_PAD4(SCTP_SAT_LEN(num_types));
257 chunksize += sizeof(ecap_param);
258
259 if (asoc->prsctp_enable)
260 chunksize += sizeof(prsctp_param);
261
262 /* ADDIP: Section 4.2.7:
263 * An implementation supporting this extension [ADDIP] MUST list
264 * the ASCONF,the ASCONF-ACK, and the AUTH chunks in its INIT and
265 * INIT-ACK parameters.
266 */
267 if (net->sctp.addip_enable) {
268 extensions[num_ext] = SCTP_CID_ASCONF;
269 extensions[num_ext+1] = SCTP_CID_ASCONF_ACK;
270 num_ext += 2;
271 }
272
273 if (sp->adaptation_ind)
274 chunksize += sizeof(aiparam);
275
276 chunksize += vparam_len;
277
278 /* Account for AUTH related parameters */
279 if (ep->auth_enable) {
280 /* Add random parameter length*/
281 chunksize += sizeof(asoc->c.auth_random);
282
283 /* Add HMACS parameter length if any were defined */
284 auth_hmacs = (sctp_paramhdr_t *)asoc->c.auth_hmacs;
285 if (auth_hmacs->length)
286 chunksize += SCTP_PAD4(ntohs(auth_hmacs->length));
287 else
288 auth_hmacs = NULL;
289
290 /* Add CHUNKS parameter length */
291 auth_chunks = (sctp_paramhdr_t *)asoc->c.auth_chunks;
292 if (auth_chunks->length)
293 chunksize += SCTP_PAD4(ntohs(auth_chunks->length));
294 else
295 auth_chunks = NULL;
296
297 extensions[num_ext] = SCTP_CID_AUTH;
298 num_ext += 1;
299 }
300
301 /* If we have any extensions to report, account for that */
302 if (num_ext)
303 chunksize += SCTP_PAD4(sizeof(sctp_supported_ext_param_t) +
304 num_ext);
305
306 /* RFC 2960 3.3.2 Initiation (INIT) (1)
307 *
308 * Note 3: An INIT chunk MUST NOT contain more than one Host
309 * Name address parameter. Moreover, the sender of the INIT
310 * MUST NOT combine any other address types with the Host Name
311 * address in the INIT. The receiver of INIT MUST ignore any
312 * other address types if the Host Name address parameter is
313 * present in the received INIT chunk.
314 *
315 * PLEASE DO NOT FIXME [This version does not support Host Name.]
316 */
317
318 retval = sctp_make_control(asoc, SCTP_CID_INIT, 0, chunksize, gfp);
319 if (!retval)
320 goto nodata;
321
322 retval->subh.init_hdr =
323 sctp_addto_chunk(retval, sizeof(init), &init);
324 retval->param_hdr.v =
325 sctp_addto_chunk(retval, addrs_len, addrs.v);
326
327 /* RFC 2960 3.3.2 Initiation (INIT) (1)
328 *
329 * Note 4: This parameter, when present, specifies all the
330 * address types the sending endpoint can support. The absence
331 * of this parameter indicates that the sending endpoint can
332 * support any address type.
333 */
334 sat.param_hdr.type = SCTP_PARAM_SUPPORTED_ADDRESS_TYPES;
335 sat.param_hdr.length = htons(SCTP_SAT_LEN(num_types));
336 sctp_addto_chunk(retval, sizeof(sat), &sat);
337 sctp_addto_chunk(retval, num_types * sizeof(__u16), &types);
338
339 sctp_addto_chunk(retval, sizeof(ecap_param), &ecap_param);
340
341 /* Add the supported extensions parameter. Be nice and add this
342 * fist before addiding the parameters for the extensions themselves
343 */
344 if (num_ext) {
345 ext_param.param_hdr.type = SCTP_PARAM_SUPPORTED_EXT;
346 ext_param.param_hdr.length =
347 htons(sizeof(sctp_supported_ext_param_t) + num_ext);
348 sctp_addto_chunk(retval, sizeof(sctp_supported_ext_param_t),
349 &ext_param);
350 sctp_addto_param(retval, num_ext, extensions);
351 }
352
353 if (asoc->prsctp_enable)
354 sctp_addto_chunk(retval, sizeof(prsctp_param), &prsctp_param);
355
356 if (sp->adaptation_ind) {
357 aiparam.param_hdr.type = SCTP_PARAM_ADAPTATION_LAYER_IND;
358 aiparam.param_hdr.length = htons(sizeof(aiparam));
359 aiparam.adaptation_ind = htonl(sp->adaptation_ind);
360 sctp_addto_chunk(retval, sizeof(aiparam), &aiparam);
361 }
362
363 /* Add SCTP-AUTH chunks to the parameter list */
364 if (ep->auth_enable) {
365 sctp_addto_chunk(retval, sizeof(asoc->c.auth_random),
366 asoc->c.auth_random);
367 if (auth_hmacs)
368 sctp_addto_chunk(retval, ntohs(auth_hmacs->length),
369 auth_hmacs);
370 if (auth_chunks)
371 sctp_addto_chunk(retval, ntohs(auth_chunks->length),
372 auth_chunks);
373 }
374 nodata:
375 kfree(addrs.v);
376 return retval;
377 }
378
379 struct sctp_chunk *sctp_make_init_ack(const struct sctp_association *asoc,
380 const struct sctp_chunk *chunk,
381 gfp_t gfp, int unkparam_len)
382 {
383 sctp_inithdr_t initack;
384 struct sctp_chunk *retval;
385 union sctp_params addrs;
386 struct sctp_sock *sp;
387 int addrs_len;
388 sctp_cookie_param_t *cookie;
389 int cookie_len;
390 size_t chunksize;
391 sctp_adaptation_ind_param_t aiparam;
392 sctp_supported_ext_param_t ext_param;
393 int num_ext = 0;
394 __u8 extensions[3];
395 sctp_paramhdr_t *auth_chunks = NULL,
396 *auth_hmacs = NULL,
397 *auth_random = NULL;
398
399 retval = NULL;
400
401 /* Note: there may be no addresses to embed. */
402 addrs = sctp_bind_addrs_to_raw(&asoc->base.bind_addr, &addrs_len, gfp);
403
404 initack.init_tag = htonl(asoc->c.my_vtag);
405 initack.a_rwnd = htonl(asoc->rwnd);
406 initack.num_outbound_streams = htons(asoc->c.sinit_num_ostreams);
407 initack.num_inbound_streams = htons(asoc->c.sinit_max_instreams);
408 initack.initial_tsn = htonl(asoc->c.initial_tsn);
409
410 /* FIXME: We really ought to build the cookie right
411 * into the packet instead of allocating more fresh memory.
412 */
413 cookie = sctp_pack_cookie(asoc->ep, asoc, chunk, &cookie_len,
414 addrs.v, addrs_len);
415 if (!cookie)
416 goto nomem_cookie;
417
418 /* Calculate the total size of allocation, include the reserved
419 * space for reporting unknown parameters if it is specified.
420 */
421 sp = sctp_sk(asoc->base.sk);
422 chunksize = sizeof(initack) + addrs_len + cookie_len + unkparam_len;
423
424 /* Tell peer that we'll do ECN only if peer advertised such cap. */
425 if (asoc->peer.ecn_capable)
426 chunksize += sizeof(ecap_param);
427
428 if (asoc->peer.prsctp_capable)
429 chunksize += sizeof(prsctp_param);
430
431 if (asoc->peer.asconf_capable) {
432 extensions[num_ext] = SCTP_CID_ASCONF;
433 extensions[num_ext+1] = SCTP_CID_ASCONF_ACK;
434 num_ext += 2;
435 }
436
437 if (sp->adaptation_ind)
438 chunksize += sizeof(aiparam);
439
440 if (asoc->peer.auth_capable) {
441 auth_random = (sctp_paramhdr_t *)asoc->c.auth_random;
442 chunksize += ntohs(auth_random->length);
443
444 auth_hmacs = (sctp_paramhdr_t *)asoc->c.auth_hmacs;
445 if (auth_hmacs->length)
446 chunksize += SCTP_PAD4(ntohs(auth_hmacs->length));
447 else
448 auth_hmacs = NULL;
449
450 auth_chunks = (sctp_paramhdr_t *)asoc->c.auth_chunks;
451 if (auth_chunks->length)
452 chunksize += SCTP_PAD4(ntohs(auth_chunks->length));
453 else
454 auth_chunks = NULL;
455
456 extensions[num_ext] = SCTP_CID_AUTH;
457 num_ext += 1;
458 }
459
460 if (num_ext)
461 chunksize += SCTP_PAD4(sizeof(sctp_supported_ext_param_t) +
462 num_ext);
463
464 /* Now allocate and fill out the chunk. */
465 retval = sctp_make_control(asoc, SCTP_CID_INIT_ACK, 0, chunksize, gfp);
466 if (!retval)
467 goto nomem_chunk;
468
469 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
470 *
471 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
472 * HEARTBEAT ACK, * etc.) to the same destination transport
473 * address from which it received the DATA or control chunk
474 * to which it is replying.
475 *
476 * [INIT ACK back to where the INIT came from.]
477 */
478 retval->transport = chunk->transport;
479
480 retval->subh.init_hdr =
481 sctp_addto_chunk(retval, sizeof(initack), &initack);
482 retval->param_hdr.v = sctp_addto_chunk(retval, addrs_len, addrs.v);
483 sctp_addto_chunk(retval, cookie_len, cookie);
484 if (asoc->peer.ecn_capable)
485 sctp_addto_chunk(retval, sizeof(ecap_param), &ecap_param);
486 if (num_ext) {
487 ext_param.param_hdr.type = SCTP_PARAM_SUPPORTED_EXT;
488 ext_param.param_hdr.length =
489 htons(sizeof(sctp_supported_ext_param_t) + num_ext);
490 sctp_addto_chunk(retval, sizeof(sctp_supported_ext_param_t),
491 &ext_param);
492 sctp_addto_param(retval, num_ext, extensions);
493 }
494 if (asoc->peer.prsctp_capable)
495 sctp_addto_chunk(retval, sizeof(prsctp_param), &prsctp_param);
496
497 if (sp->adaptation_ind) {
498 aiparam.param_hdr.type = SCTP_PARAM_ADAPTATION_LAYER_IND;
499 aiparam.param_hdr.length = htons(sizeof(aiparam));
500 aiparam.adaptation_ind = htonl(sp->adaptation_ind);
501 sctp_addto_chunk(retval, sizeof(aiparam), &aiparam);
502 }
503
504 if (asoc->peer.auth_capable) {
505 sctp_addto_chunk(retval, ntohs(auth_random->length),
506 auth_random);
507 if (auth_hmacs)
508 sctp_addto_chunk(retval, ntohs(auth_hmacs->length),
509 auth_hmacs);
510 if (auth_chunks)
511 sctp_addto_chunk(retval, ntohs(auth_chunks->length),
512 auth_chunks);
513 }
514
515 /* We need to remove the const qualifier at this point. */
516 retval->asoc = (struct sctp_association *) asoc;
517
518 nomem_chunk:
519 kfree(cookie);
520 nomem_cookie:
521 kfree(addrs.v);
522 return retval;
523 }
524
525 /* 3.3.11 Cookie Echo (COOKIE ECHO) (10):
526 *
527 * This chunk is used only during the initialization of an association.
528 * It is sent by the initiator of an association to its peer to complete
529 * the initialization process. This chunk MUST precede any DATA chunk
530 * sent within the association, but MAY be bundled with one or more DATA
531 * chunks in the same packet.
532 *
533 * 0 1 2 3
534 * 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
535 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
536 * | Type = 10 |Chunk Flags | Length |
537 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
538 * / Cookie /
539 * \ \
540 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
541 *
542 * Chunk Flags: 8 bit
543 *
544 * Set to zero on transmit and ignored on receipt.
545 *
546 * Length: 16 bits (unsigned integer)
547 *
548 * Set to the size of the chunk in bytes, including the 4 bytes of
549 * the chunk header and the size of the Cookie.
550 *
551 * Cookie: variable size
552 *
553 * This field must contain the exact cookie received in the
554 * State Cookie parameter from the previous INIT ACK.
555 *
556 * An implementation SHOULD make the cookie as small as possible
557 * to insure interoperability.
558 */
559 struct sctp_chunk *sctp_make_cookie_echo(const struct sctp_association *asoc,
560 const struct sctp_chunk *chunk)
561 {
562 struct sctp_chunk *retval;
563 void *cookie;
564 int cookie_len;
565
566 cookie = asoc->peer.cookie;
567 cookie_len = asoc->peer.cookie_len;
568
569 /* Build a cookie echo chunk. */
570 retval = sctp_make_control(asoc, SCTP_CID_COOKIE_ECHO, 0,
571 cookie_len, GFP_ATOMIC);
572 if (!retval)
573 goto nodata;
574 retval->subh.cookie_hdr =
575 sctp_addto_chunk(retval, cookie_len, cookie);
576
577 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
578 *
579 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
580 * HEARTBEAT ACK, * etc.) to the same destination transport
581 * address from which it * received the DATA or control chunk
582 * to which it is replying.
583 *
584 * [COOKIE ECHO back to where the INIT ACK came from.]
585 */
586 if (chunk)
587 retval->transport = chunk->transport;
588
589 nodata:
590 return retval;
591 }
592
593 /* 3.3.12 Cookie Acknowledgement (COOKIE ACK) (11):
594 *
595 * This chunk is used only during the initialization of an
596 * association. It is used to acknowledge the receipt of a COOKIE
597 * ECHO chunk. This chunk MUST precede any DATA or SACK chunk sent
598 * within the association, but MAY be bundled with one or more DATA
599 * chunks or SACK chunk in the same SCTP packet.
600 *
601 * 0 1 2 3
602 * 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
603 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
604 * | Type = 11 |Chunk Flags | Length = 4 |
605 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
606 *
607 * Chunk Flags: 8 bits
608 *
609 * Set to zero on transmit and ignored on receipt.
610 */
611 struct sctp_chunk *sctp_make_cookie_ack(const struct sctp_association *asoc,
612 const struct sctp_chunk *chunk)
613 {
614 struct sctp_chunk *retval;
615
616 retval = sctp_make_control(asoc, SCTP_CID_COOKIE_ACK, 0, 0, GFP_ATOMIC);
617
618 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
619 *
620 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
621 * HEARTBEAT ACK, * etc.) to the same destination transport
622 * address from which it * received the DATA or control chunk
623 * to which it is replying.
624 *
625 * [COOKIE ACK back to where the COOKIE ECHO came from.]
626 */
627 if (retval && chunk)
628 retval->transport = chunk->transport;
629
630 return retval;
631 }
632
633 /*
634 * Appendix A: Explicit Congestion Notification:
635 * CWR:
636 *
637 * RFC 2481 details a specific bit for a sender to send in the header of
638 * its next outbound TCP segment to indicate to its peer that it has
639 * reduced its congestion window. This is termed the CWR bit. For
640 * SCTP the same indication is made by including the CWR chunk.
641 * This chunk contains one data element, i.e. the TSN number that
642 * was sent in the ECNE chunk. This element represents the lowest
643 * TSN number in the datagram that was originally marked with the
644 * CE bit.
645 *
646 * 0 1 2 3
647 * 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
648 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
649 * | Chunk Type=13 | Flags=00000000| Chunk Length = 8 |
650 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
651 * | Lowest TSN Number |
652 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
653 *
654 * Note: The CWR is considered a Control chunk.
655 */
656 struct sctp_chunk *sctp_make_cwr(const struct sctp_association *asoc,
657 const __u32 lowest_tsn,
658 const struct sctp_chunk *chunk)
659 {
660 struct sctp_chunk *retval;
661 sctp_cwrhdr_t cwr;
662
663 cwr.lowest_tsn = htonl(lowest_tsn);
664 retval = sctp_make_control(asoc, SCTP_CID_ECN_CWR, 0,
665 sizeof(sctp_cwrhdr_t), GFP_ATOMIC);
666
667 if (!retval)
668 goto nodata;
669
670 retval->subh.ecn_cwr_hdr =
671 sctp_addto_chunk(retval, sizeof(cwr), &cwr);
672
673 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
674 *
675 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
676 * HEARTBEAT ACK, * etc.) to the same destination transport
677 * address from which it * received the DATA or control chunk
678 * to which it is replying.
679 *
680 * [Report a reduced congestion window back to where the ECNE
681 * came from.]
682 */
683 if (chunk)
684 retval->transport = chunk->transport;
685
686 nodata:
687 return retval;
688 }
689
690 /* Make an ECNE chunk. This is a congestion experienced report. */
691 struct sctp_chunk *sctp_make_ecne(const struct sctp_association *asoc,
692 const __u32 lowest_tsn)
693 {
694 struct sctp_chunk *retval;
695 sctp_ecnehdr_t ecne;
696
697 ecne.lowest_tsn = htonl(lowest_tsn);
698 retval = sctp_make_control(asoc, SCTP_CID_ECN_ECNE, 0,
699 sizeof(sctp_ecnehdr_t), GFP_ATOMIC);
700 if (!retval)
701 goto nodata;
702 retval->subh.ecne_hdr =
703 sctp_addto_chunk(retval, sizeof(ecne), &ecne);
704
705 nodata:
706 return retval;
707 }
708
709 /* Make a DATA chunk for the given association from the provided
710 * parameters. However, do not populate the data payload.
711 */
712 struct sctp_chunk *sctp_make_datafrag_empty(struct sctp_association *asoc,
713 const struct sctp_sndrcvinfo *sinfo,
714 int data_len, __u8 flags, __u16 ssn,
715 gfp_t gfp)
716 {
717 struct sctp_chunk *retval;
718 struct sctp_datahdr dp;
719 int chunk_len;
720
721 /* We assign the TSN as LATE as possible, not here when
722 * creating the chunk.
723 */
724 dp.tsn = 0;
725 dp.stream = htons(sinfo->sinfo_stream);
726 dp.ppid = sinfo->sinfo_ppid;
727
728 /* Set the flags for an unordered send. */
729 if (sinfo->sinfo_flags & SCTP_UNORDERED) {
730 flags |= SCTP_DATA_UNORDERED;
731 dp.ssn = 0;
732 } else
733 dp.ssn = htons(ssn);
734
735 chunk_len = sizeof(dp) + data_len;
736 retval = sctp_make_data(asoc, flags, chunk_len, gfp);
737 if (!retval)
738 goto nodata;
739
740 retval->subh.data_hdr = sctp_addto_chunk(retval, sizeof(dp), &dp);
741 memcpy(&retval->sinfo, sinfo, sizeof(struct sctp_sndrcvinfo));
742
743 nodata:
744 return retval;
745 }
746
747 /* Create a selective ackowledgement (SACK) for the given
748 * association. This reports on which TSN's we've seen to date,
749 * including duplicates and gaps.
750 */
751 struct sctp_chunk *sctp_make_sack(const struct sctp_association *asoc)
752 {
753 struct sctp_chunk *retval;
754 struct sctp_sackhdr sack;
755 int len;
756 __u32 ctsn;
757 __u16 num_gabs, num_dup_tsns;
758 struct sctp_association *aptr = (struct sctp_association *)asoc;
759 struct sctp_tsnmap *map = (struct sctp_tsnmap *)&asoc->peer.tsn_map;
760 struct sctp_gap_ack_block gabs[SCTP_MAX_GABS];
761 struct sctp_transport *trans;
762
763 memset(gabs, 0, sizeof(gabs));
764 ctsn = sctp_tsnmap_get_ctsn(map);
765
766 pr_debug("%s: sackCTSNAck sent:0x%x\n", __func__, ctsn);
767
768 /* How much room is needed in the chunk? */
769 num_gabs = sctp_tsnmap_num_gabs(map, gabs);
770 num_dup_tsns = sctp_tsnmap_num_dups(map);
771
772 /* Initialize the SACK header. */
773 sack.cum_tsn_ack = htonl(ctsn);
774 sack.a_rwnd = htonl(asoc->a_rwnd);
775 sack.num_gap_ack_blocks = htons(num_gabs);
776 sack.num_dup_tsns = htons(num_dup_tsns);
777
778 len = sizeof(sack)
779 + sizeof(struct sctp_gap_ack_block) * num_gabs
780 + sizeof(__u32) * num_dup_tsns;
781
782 /* Create the chunk. */
783 retval = sctp_make_control(asoc, SCTP_CID_SACK, 0, len, GFP_ATOMIC);
784 if (!retval)
785 goto nodata;
786
787 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
788 *
789 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
790 * HEARTBEAT ACK, etc.) to the same destination transport
791 * address from which it received the DATA or control chunk to
792 * which it is replying. This rule should also be followed if
793 * the endpoint is bundling DATA chunks together with the
794 * reply chunk.
795 *
796 * However, when acknowledging multiple DATA chunks received
797 * in packets from different source addresses in a single
798 * SACK, the SACK chunk may be transmitted to one of the
799 * destination transport addresses from which the DATA or
800 * control chunks being acknowledged were received.
801 *
802 * [BUG: We do not implement the following paragraph.
803 * Perhaps we should remember the last transport we used for a
804 * SACK and avoid that (if possible) if we have seen any
805 * duplicates. --piggy]
806 *
807 * When a receiver of a duplicate DATA chunk sends a SACK to a
808 * multi- homed endpoint it MAY be beneficial to vary the
809 * destination address and not use the source address of the
810 * DATA chunk. The reason being that receiving a duplicate
811 * from a multi-homed endpoint might indicate that the return
812 * path (as specified in the source address of the DATA chunk)
813 * for the SACK is broken.
814 *
815 * [Send to the address from which we last received a DATA chunk.]
816 */
817 retval->transport = asoc->peer.last_data_from;
818
819 retval->subh.sack_hdr =
820 sctp_addto_chunk(retval, sizeof(sack), &sack);
821
822 /* Add the gap ack block information. */
823 if (num_gabs)
824 sctp_addto_chunk(retval, sizeof(__u32) * num_gabs,
825 gabs);
826
827 /* Add the duplicate TSN information. */
828 if (num_dup_tsns) {
829 aptr->stats.idupchunks += num_dup_tsns;
830 sctp_addto_chunk(retval, sizeof(__u32) * num_dup_tsns,
831 sctp_tsnmap_get_dups(map));
832 }
833 /* Once we have a sack generated, check to see what our sack
834 * generation is, if its 0, reset the transports to 0, and reset
835 * the association generation to 1
836 *
837 * The idea is that zero is never used as a valid generation for the
838 * association so no transport will match after a wrap event like this,
839 * Until the next sack
840 */
841 if (++aptr->peer.sack_generation == 0) {
842 list_for_each_entry(trans, &asoc->peer.transport_addr_list,
843 transports)
844 trans->sack_generation = 0;
845 aptr->peer.sack_generation = 1;
846 }
847 nodata:
848 return retval;
849 }
850
851 /* Make a SHUTDOWN chunk. */
852 struct sctp_chunk *sctp_make_shutdown(const struct sctp_association *asoc,
853 const struct sctp_chunk *chunk)
854 {
855 struct sctp_chunk *retval;
856 sctp_shutdownhdr_t shut;
857 __u32 ctsn;
858
859 ctsn = sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map);
860 shut.cum_tsn_ack = htonl(ctsn);
861
862 retval = sctp_make_control(asoc, SCTP_CID_SHUTDOWN, 0,
863 sizeof(sctp_shutdownhdr_t), GFP_ATOMIC);
864 if (!retval)
865 goto nodata;
866
867 retval->subh.shutdown_hdr =
868 sctp_addto_chunk(retval, sizeof(shut), &shut);
869
870 if (chunk)
871 retval->transport = chunk->transport;
872 nodata:
873 return retval;
874 }
875
876 struct sctp_chunk *sctp_make_shutdown_ack(const struct sctp_association *asoc,
877 const struct sctp_chunk *chunk)
878 {
879 struct sctp_chunk *retval;
880
881 retval = sctp_make_control(asoc, SCTP_CID_SHUTDOWN_ACK, 0, 0,
882 GFP_ATOMIC);
883
884 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
885 *
886 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
887 * HEARTBEAT ACK, * etc.) to the same destination transport
888 * address from which it * received the DATA or control chunk
889 * to which it is replying.
890 *
891 * [ACK back to where the SHUTDOWN came from.]
892 */
893 if (retval && chunk)
894 retval->transport = chunk->transport;
895
896 return retval;
897 }
898
899 struct sctp_chunk *sctp_make_shutdown_complete(
900 const struct sctp_association *asoc,
901 const struct sctp_chunk *chunk)
902 {
903 struct sctp_chunk *retval;
904 __u8 flags = 0;
905
906 /* Set the T-bit if we have no association (vtag will be
907 * reflected)
908 */
909 flags |= asoc ? 0 : SCTP_CHUNK_FLAG_T;
910
911 retval = sctp_make_control(asoc, SCTP_CID_SHUTDOWN_COMPLETE, flags,
912 0, GFP_ATOMIC);
913
914 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
915 *
916 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
917 * HEARTBEAT ACK, * etc.) to the same destination transport
918 * address from which it * received the DATA or control chunk
919 * to which it is replying.
920 *
921 * [Report SHUTDOWN COMPLETE back to where the SHUTDOWN ACK
922 * came from.]
923 */
924 if (retval && chunk)
925 retval->transport = chunk->transport;
926
927 return retval;
928 }
929
930 /* Create an ABORT. Note that we set the T bit if we have no
931 * association, except when responding to an INIT (sctpimpguide 2.41).
932 */
933 struct sctp_chunk *sctp_make_abort(const struct sctp_association *asoc,
934 const struct sctp_chunk *chunk,
935 const size_t hint)
936 {
937 struct sctp_chunk *retval;
938 __u8 flags = 0;
939
940 /* Set the T-bit if we have no association and 'chunk' is not
941 * an INIT (vtag will be reflected).
942 */
943 if (!asoc) {
944 if (chunk && chunk->chunk_hdr &&
945 chunk->chunk_hdr->type == SCTP_CID_INIT)
946 flags = 0;
947 else
948 flags = SCTP_CHUNK_FLAG_T;
949 }
950
951 retval = sctp_make_control(asoc, SCTP_CID_ABORT, flags, hint,
952 GFP_ATOMIC);
953
954 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
955 *
956 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
957 * HEARTBEAT ACK, * etc.) to the same destination transport
958 * address from which it * received the DATA or control chunk
959 * to which it is replying.
960 *
961 * [ABORT back to where the offender came from.]
962 */
963 if (retval && chunk)
964 retval->transport = chunk->transport;
965
966 return retval;
967 }
968
969 /* Helper to create ABORT with a NO_USER_DATA error. */
970 struct sctp_chunk *sctp_make_abort_no_data(
971 const struct sctp_association *asoc,
972 const struct sctp_chunk *chunk, __u32 tsn)
973 {
974 struct sctp_chunk *retval;
975 __be32 payload;
976
977 retval = sctp_make_abort(asoc, chunk, sizeof(sctp_errhdr_t)
978 + sizeof(tsn));
979
980 if (!retval)
981 goto no_mem;
982
983 /* Put the tsn back into network byte order. */
984 payload = htonl(tsn);
985 sctp_init_cause(retval, SCTP_ERROR_NO_DATA, sizeof(payload));
986 sctp_addto_chunk(retval, sizeof(payload), (const void *)&payload);
987
988 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
989 *
990 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
991 * HEARTBEAT ACK, * etc.) to the same destination transport
992 * address from which it * received the DATA or control chunk
993 * to which it is replying.
994 *
995 * [ABORT back to where the offender came from.]
996 */
997 if (chunk)
998 retval->transport = chunk->transport;
999
1000 no_mem:
1001 return retval;
1002 }
1003
1004 /* Helper to create ABORT with a SCTP_ERROR_USER_ABORT error. */
1005 struct sctp_chunk *sctp_make_abort_user(const struct sctp_association *asoc,
1006 struct msghdr *msg,
1007 size_t paylen)
1008 {
1009 struct sctp_chunk *retval;
1010 void *payload = NULL;
1011 int err;
1012
1013 retval = sctp_make_abort(asoc, NULL, sizeof(sctp_errhdr_t) + paylen);
1014 if (!retval)
1015 goto err_chunk;
1016
1017 if (paylen) {
1018 /* Put the msg_iov together into payload. */
1019 payload = kmalloc(paylen, GFP_KERNEL);
1020 if (!payload)
1021 goto err_payload;
1022
1023 err = memcpy_from_msg(payload, msg, paylen);
1024 if (err < 0)
1025 goto err_copy;
1026 }
1027
1028 sctp_init_cause(retval, SCTP_ERROR_USER_ABORT, paylen);
1029 sctp_addto_chunk(retval, paylen, payload);
1030
1031 if (paylen)
1032 kfree(payload);
1033
1034 return retval;
1035
1036 err_copy:
1037 kfree(payload);
1038 err_payload:
1039 sctp_chunk_free(retval);
1040 retval = NULL;
1041 err_chunk:
1042 return retval;
1043 }
1044
1045 /* Append bytes to the end of a parameter. Will panic if chunk is not big
1046 * enough.
1047 */
1048 static void *sctp_addto_param(struct sctp_chunk *chunk, int len,
1049 const void *data)
1050 {
1051 void *target;
1052 int chunklen = ntohs(chunk->chunk_hdr->length);
1053
1054 target = skb_put(chunk->skb, len);
1055
1056 if (data)
1057 memcpy(target, data, len);
1058 else
1059 memset(target, 0, len);
1060
1061 /* Adjust the chunk length field. */
1062 chunk->chunk_hdr->length = htons(chunklen + len);
1063 chunk->chunk_end = skb_tail_pointer(chunk->skb);
1064
1065 return target;
1066 }
1067
1068 /* Make an ABORT chunk with a PROTOCOL VIOLATION cause code. */
1069 struct sctp_chunk *sctp_make_abort_violation(
1070 const struct sctp_association *asoc,
1071 const struct sctp_chunk *chunk,
1072 const __u8 *payload,
1073 const size_t paylen)
1074 {
1075 struct sctp_chunk *retval;
1076 struct sctp_paramhdr phdr;
1077
1078 retval = sctp_make_abort(asoc, chunk, sizeof(sctp_errhdr_t) + paylen
1079 + sizeof(sctp_paramhdr_t));
1080 if (!retval)
1081 goto end;
1082
1083 sctp_init_cause(retval, SCTP_ERROR_PROTO_VIOLATION, paylen
1084 + sizeof(sctp_paramhdr_t));
1085
1086 phdr.type = htons(chunk->chunk_hdr->type);
1087 phdr.length = chunk->chunk_hdr->length;
1088 sctp_addto_chunk(retval, paylen, payload);
1089 sctp_addto_param(retval, sizeof(sctp_paramhdr_t), &phdr);
1090
1091 end:
1092 return retval;
1093 }
1094
1095 struct sctp_chunk *sctp_make_violation_paramlen(
1096 const struct sctp_association *asoc,
1097 const struct sctp_chunk *chunk,
1098 struct sctp_paramhdr *param)
1099 {
1100 struct sctp_chunk *retval;
1101 static const char error[] = "The following parameter had invalid length:";
1102 size_t payload_len = sizeof(error) + sizeof(sctp_errhdr_t) +
1103 sizeof(sctp_paramhdr_t);
1104
1105 retval = sctp_make_abort(asoc, chunk, payload_len);
1106 if (!retval)
1107 goto nodata;
1108
1109 sctp_init_cause(retval, SCTP_ERROR_PROTO_VIOLATION,
1110 sizeof(error) + sizeof(sctp_paramhdr_t));
1111 sctp_addto_chunk(retval, sizeof(error), error);
1112 sctp_addto_param(retval, sizeof(sctp_paramhdr_t), param);
1113
1114 nodata:
1115 return retval;
1116 }
1117
1118 struct sctp_chunk *sctp_make_violation_max_retrans(
1119 const struct sctp_association *asoc,
1120 const struct sctp_chunk *chunk)
1121 {
1122 struct sctp_chunk *retval;
1123 static const char error[] = "Association exceeded its max_retans count";
1124 size_t payload_len = sizeof(error) + sizeof(sctp_errhdr_t);
1125
1126 retval = sctp_make_abort(asoc, chunk, payload_len);
1127 if (!retval)
1128 goto nodata;
1129
1130 sctp_init_cause(retval, SCTP_ERROR_PROTO_VIOLATION, sizeof(error));
1131 sctp_addto_chunk(retval, sizeof(error), error);
1132
1133 nodata:
1134 return retval;
1135 }
1136
1137 /* Make a HEARTBEAT chunk. */
1138 struct sctp_chunk *sctp_make_heartbeat(const struct sctp_association *asoc,
1139 const struct sctp_transport *transport)
1140 {
1141 struct sctp_chunk *retval;
1142 sctp_sender_hb_info_t hbinfo;
1143
1144 retval = sctp_make_control(asoc, SCTP_CID_HEARTBEAT, 0,
1145 sizeof(hbinfo), GFP_ATOMIC);
1146
1147 if (!retval)
1148 goto nodata;
1149
1150 hbinfo.param_hdr.type = SCTP_PARAM_HEARTBEAT_INFO;
1151 hbinfo.param_hdr.length = htons(sizeof(sctp_sender_hb_info_t));
1152 hbinfo.daddr = transport->ipaddr;
1153 hbinfo.sent_at = jiffies;
1154 hbinfo.hb_nonce = transport->hb_nonce;
1155
1156 /* Cast away the 'const', as this is just telling the chunk
1157 * what transport it belongs to.
1158 */
1159 retval->transport = (struct sctp_transport *) transport;
1160 retval->subh.hbs_hdr = sctp_addto_chunk(retval, sizeof(hbinfo),
1161 &hbinfo);
1162
1163 nodata:
1164 return retval;
1165 }
1166
1167 struct sctp_chunk *sctp_make_heartbeat_ack(const struct sctp_association *asoc,
1168 const struct sctp_chunk *chunk,
1169 const void *payload, const size_t paylen)
1170 {
1171 struct sctp_chunk *retval;
1172
1173 retval = sctp_make_control(asoc, SCTP_CID_HEARTBEAT_ACK, 0, paylen,
1174 GFP_ATOMIC);
1175 if (!retval)
1176 goto nodata;
1177
1178 retval->subh.hbs_hdr = sctp_addto_chunk(retval, paylen, payload);
1179
1180 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
1181 *
1182 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
1183 * HEARTBEAT ACK, * etc.) to the same destination transport
1184 * address from which it * received the DATA or control chunk
1185 * to which it is replying.
1186 *
1187 * [HBACK back to where the HEARTBEAT came from.]
1188 */
1189 if (chunk)
1190 retval->transport = chunk->transport;
1191
1192 nodata:
1193 return retval;
1194 }
1195
1196 /* Create an Operation Error chunk with the specified space reserved.
1197 * This routine can be used for containing multiple causes in the chunk.
1198 */
1199 static struct sctp_chunk *sctp_make_op_error_space(
1200 const struct sctp_association *asoc,
1201 const struct sctp_chunk *chunk,
1202 size_t size)
1203 {
1204 struct sctp_chunk *retval;
1205
1206 retval = sctp_make_control(asoc, SCTP_CID_ERROR, 0,
1207 sizeof(sctp_errhdr_t) + size, GFP_ATOMIC);
1208 if (!retval)
1209 goto nodata;
1210
1211 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
1212 *
1213 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
1214 * HEARTBEAT ACK, etc.) to the same destination transport
1215 * address from which it received the DATA or control chunk
1216 * to which it is replying.
1217 *
1218 */
1219 if (chunk)
1220 retval->transport = chunk->transport;
1221
1222 nodata:
1223 return retval;
1224 }
1225
1226 /* Create an Operation Error chunk of a fixed size,
1227 * specifically, max(asoc->pathmtu, SCTP_DEFAULT_MAXSEGMENT)
1228 * This is a helper function to allocate an error chunk for
1229 * for those invalid parameter codes in which we may not want
1230 * to report all the errors, if the incoming chunk is large
1231 */
1232 static inline struct sctp_chunk *sctp_make_op_error_fixed(
1233 const struct sctp_association *asoc,
1234 const struct sctp_chunk *chunk)
1235 {
1236 size_t size = asoc ? asoc->pathmtu : 0;
1237
1238 if (!size)
1239 size = SCTP_DEFAULT_MAXSEGMENT;
1240
1241 return sctp_make_op_error_space(asoc, chunk, size);
1242 }
1243
1244 /* Create an Operation Error chunk. */
1245 struct sctp_chunk *sctp_make_op_error(const struct sctp_association *asoc,
1246 const struct sctp_chunk *chunk,
1247 __be16 cause_code, const void *payload,
1248 size_t paylen, size_t reserve_tail)
1249 {
1250 struct sctp_chunk *retval;
1251
1252 retval = sctp_make_op_error_space(asoc, chunk, paylen + reserve_tail);
1253 if (!retval)
1254 goto nodata;
1255
1256 sctp_init_cause(retval, cause_code, paylen + reserve_tail);
1257 sctp_addto_chunk(retval, paylen, payload);
1258 if (reserve_tail)
1259 sctp_addto_param(retval, reserve_tail, NULL);
1260
1261 nodata:
1262 return retval;
1263 }
1264
1265 struct sctp_chunk *sctp_make_auth(const struct sctp_association *asoc)
1266 {
1267 struct sctp_chunk *retval;
1268 struct sctp_hmac *hmac_desc;
1269 struct sctp_authhdr auth_hdr;
1270 __u8 *hmac;
1271
1272 /* Get the first hmac that the peer told us to use */
1273 hmac_desc = sctp_auth_asoc_get_hmac(asoc);
1274 if (unlikely(!hmac_desc))
1275 return NULL;
1276
1277 retval = sctp_make_control(asoc, SCTP_CID_AUTH, 0,
1278 hmac_desc->hmac_len + sizeof(sctp_authhdr_t),
1279 GFP_ATOMIC);
1280 if (!retval)
1281 return NULL;
1282
1283 auth_hdr.hmac_id = htons(hmac_desc->hmac_id);
1284 auth_hdr.shkey_id = htons(asoc->active_key_id);
1285
1286 retval->subh.auth_hdr = sctp_addto_chunk(retval, sizeof(sctp_authhdr_t),
1287 &auth_hdr);
1288
1289 hmac = skb_put(retval->skb, hmac_desc->hmac_len);
1290 memset(hmac, 0, hmac_desc->hmac_len);
1291
1292 /* Adjust the chunk header to include the empty MAC */
1293 retval->chunk_hdr->length =
1294 htons(ntohs(retval->chunk_hdr->length) + hmac_desc->hmac_len);
1295 retval->chunk_end = skb_tail_pointer(retval->skb);
1296
1297 return retval;
1298 }
1299
1300
1301 /********************************************************************
1302 * 2nd Level Abstractions
1303 ********************************************************************/
1304
1305 /* Turn an skb into a chunk.
1306 * FIXME: Eventually move the structure directly inside the skb->cb[].
1307 *
1308 * sctpimpguide-05.txt Section 2.8.2
1309 * M1) Each time a new DATA chunk is transmitted
1310 * set the 'TSN.Missing.Report' count for that TSN to 0. The
1311 * 'TSN.Missing.Report' count will be used to determine missing chunks
1312 * and when to fast retransmit.
1313 *
1314 */
1315 struct sctp_chunk *sctp_chunkify(struct sk_buff *skb,
1316 const struct sctp_association *asoc,
1317 struct sock *sk, gfp_t gfp)
1318 {
1319 struct sctp_chunk *retval;
1320
1321 retval = kmem_cache_zalloc(sctp_chunk_cachep, gfp);
1322
1323 if (!retval)
1324 goto nodata;
1325 if (!sk)
1326 pr_debug("%s: chunkifying skb:%p w/o an sk\n", __func__, skb);
1327
1328 INIT_LIST_HEAD(&retval->list);
1329 retval->skb = skb;
1330 retval->asoc = (struct sctp_association *)asoc;
1331 retval->singleton = 1;
1332
1333 retval->fast_retransmit = SCTP_CAN_FRTX;
1334
1335 /* Polish the bead hole. */
1336 INIT_LIST_HEAD(&retval->transmitted_list);
1337 INIT_LIST_HEAD(&retval->frag_list);
1338 SCTP_DBG_OBJCNT_INC(chunk);
1339 atomic_set(&retval->refcnt, 1);
1340
1341 nodata:
1342 return retval;
1343 }
1344
1345 /* Set chunk->source and dest based on the IP header in chunk->skb. */
1346 void sctp_init_addrs(struct sctp_chunk *chunk, union sctp_addr *src,
1347 union sctp_addr *dest)
1348 {
1349 memcpy(&chunk->source, src, sizeof(union sctp_addr));
1350 memcpy(&chunk->dest, dest, sizeof(union sctp_addr));
1351 }
1352
1353 /* Extract the source address from a chunk. */
1354 const union sctp_addr *sctp_source(const struct sctp_chunk *chunk)
1355 {
1356 /* If we have a known transport, use that. */
1357 if (chunk->transport) {
1358 return &chunk->transport->ipaddr;
1359 } else {
1360 /* Otherwise, extract it from the IP header. */
1361 return &chunk->source;
1362 }
1363 }
1364
1365 /* Create a new chunk, setting the type and flags headers from the
1366 * arguments, reserving enough space for a 'paylen' byte payload.
1367 */
1368 static struct sctp_chunk *_sctp_make_chunk(const struct sctp_association *asoc,
1369 __u8 type, __u8 flags, int paylen,
1370 gfp_t gfp)
1371 {
1372 struct sctp_chunk *retval;
1373 sctp_chunkhdr_t *chunk_hdr;
1374 struct sk_buff *skb;
1375 struct sock *sk;
1376
1377 /* No need to allocate LL here, as this is only a chunk. */
1378 skb = alloc_skb(SCTP_PAD4(sizeof(sctp_chunkhdr_t) + paylen), gfp);
1379 if (!skb)
1380 goto nodata;
1381
1382 /* Make room for the chunk header. */
1383 chunk_hdr = (sctp_chunkhdr_t *)skb_put(skb, sizeof(sctp_chunkhdr_t));
1384 chunk_hdr->type = type;
1385 chunk_hdr->flags = flags;
1386 chunk_hdr->length = htons(sizeof(sctp_chunkhdr_t));
1387
1388 sk = asoc ? asoc->base.sk : NULL;
1389 retval = sctp_chunkify(skb, asoc, sk, gfp);
1390 if (!retval) {
1391 kfree_skb(skb);
1392 goto nodata;
1393 }
1394
1395 retval->chunk_hdr = chunk_hdr;
1396 retval->chunk_end = ((__u8 *)chunk_hdr) + sizeof(struct sctp_chunkhdr);
1397
1398 /* Determine if the chunk needs to be authenticated */
1399 if (sctp_auth_send_cid(type, asoc))
1400 retval->auth = 1;
1401
1402 return retval;
1403 nodata:
1404 return NULL;
1405 }
1406
1407 static struct sctp_chunk *sctp_make_data(const struct sctp_association *asoc,
1408 __u8 flags, int paylen, gfp_t gfp)
1409 {
1410 return _sctp_make_chunk(asoc, SCTP_CID_DATA, flags, paylen, gfp);
1411 }
1412
1413 static struct sctp_chunk *sctp_make_control(const struct sctp_association *asoc,
1414 __u8 type, __u8 flags, int paylen,
1415 gfp_t gfp)
1416 {
1417 struct sctp_chunk *chunk;
1418
1419 chunk = _sctp_make_chunk(asoc, type, flags, paylen, gfp);
1420 if (chunk)
1421 sctp_control_set_owner_w(chunk);
1422
1423 return chunk;
1424 }
1425
1426 /* Release the memory occupied by a chunk. */
1427 static void sctp_chunk_destroy(struct sctp_chunk *chunk)
1428 {
1429 BUG_ON(!list_empty(&chunk->list));
1430 list_del_init(&chunk->transmitted_list);
1431
1432 consume_skb(chunk->skb);
1433 consume_skb(chunk->auth_chunk);
1434
1435 SCTP_DBG_OBJCNT_DEC(chunk);
1436 kmem_cache_free(sctp_chunk_cachep, chunk);
1437 }
1438
1439 /* Possibly, free the chunk. */
1440 void sctp_chunk_free(struct sctp_chunk *chunk)
1441 {
1442 /* Release our reference on the message tracker. */
1443 if (chunk->msg)
1444 sctp_datamsg_put(chunk->msg);
1445
1446 sctp_chunk_put(chunk);
1447 }
1448
1449 /* Grab a reference to the chunk. */
1450 void sctp_chunk_hold(struct sctp_chunk *ch)
1451 {
1452 atomic_inc(&ch->refcnt);
1453 }
1454
1455 /* Release a reference to the chunk. */
1456 void sctp_chunk_put(struct sctp_chunk *ch)
1457 {
1458 if (atomic_dec_and_test(&ch->refcnt))
1459 sctp_chunk_destroy(ch);
1460 }
1461
1462 /* Append bytes to the end of a chunk. Will panic if chunk is not big
1463 * enough.
1464 */
1465 void *sctp_addto_chunk(struct sctp_chunk *chunk, int len, const void *data)
1466 {
1467 void *target;
1468 void *padding;
1469 int chunklen = ntohs(chunk->chunk_hdr->length);
1470 int padlen = SCTP_PAD4(chunklen) - chunklen;
1471
1472 padding = skb_put(chunk->skb, padlen);
1473 target = skb_put(chunk->skb, len);
1474
1475 memset(padding, 0, padlen);
1476 memcpy(target, data, len);
1477
1478 /* Adjust the chunk length field. */
1479 chunk->chunk_hdr->length = htons(chunklen + padlen + len);
1480 chunk->chunk_end = skb_tail_pointer(chunk->skb);
1481
1482 return target;
1483 }
1484
1485 /* Append bytes to the end of a chunk. Returns NULL if there isn't sufficient
1486 * space in the chunk
1487 */
1488 static void *sctp_addto_chunk_fixed(struct sctp_chunk *chunk,
1489 int len, const void *data)
1490 {
1491 if (skb_tailroom(chunk->skb) >= len)
1492 return sctp_addto_chunk(chunk, len, data);
1493 else
1494 return NULL;
1495 }
1496
1497 /* Append bytes from user space to the end of a chunk. Will panic if
1498 * chunk is not big enough.
1499 * Returns a kernel err value.
1500 */
1501 int sctp_user_addto_chunk(struct sctp_chunk *chunk, int len,
1502 struct iov_iter *from)
1503 {
1504 void *target;
1505 ssize_t copied;
1506
1507 /* Make room in chunk for data. */
1508 target = skb_put(chunk->skb, len);
1509
1510 /* Copy data (whole iovec) into chunk */
1511 copied = copy_from_iter(target, len, from);
1512 if (copied != len)
1513 return -EFAULT;
1514
1515 /* Adjust the chunk length field. */
1516 chunk->chunk_hdr->length =
1517 htons(ntohs(chunk->chunk_hdr->length) + len);
1518 chunk->chunk_end = skb_tail_pointer(chunk->skb);
1519
1520 return 0;
1521 }
1522
1523 /* Helper function to assign a TSN if needed. This assumes that both
1524 * the data_hdr and association have already been assigned.
1525 */
1526 void sctp_chunk_assign_ssn(struct sctp_chunk *chunk)
1527 {
1528 struct sctp_datamsg *msg;
1529 struct sctp_chunk *lchunk;
1530 struct sctp_stream *stream;
1531 __u16 ssn;
1532 __u16 sid;
1533
1534 if (chunk->has_ssn)
1535 return;
1536
1537 /* All fragments will be on the same stream */
1538 sid = ntohs(chunk->subh.data_hdr->stream);
1539 stream = &chunk->asoc->ssnmap->out;
1540
1541 /* Now assign the sequence number to the entire message.
1542 * All fragments must have the same stream sequence number.
1543 */
1544 msg = chunk->msg;
1545 list_for_each_entry(lchunk, &msg->chunks, frag_list) {
1546 if (lchunk->chunk_hdr->flags & SCTP_DATA_UNORDERED) {
1547 ssn = 0;
1548 } else {
1549 if (lchunk->chunk_hdr->flags & SCTP_DATA_LAST_FRAG)
1550 ssn = sctp_ssn_next(stream, sid);
1551 else
1552 ssn = sctp_ssn_peek(stream, sid);
1553 }
1554
1555 lchunk->subh.data_hdr->ssn = htons(ssn);
1556 lchunk->has_ssn = 1;
1557 }
1558 }
1559
1560 /* Helper function to assign a TSN if needed. This assumes that both
1561 * the data_hdr and association have already been assigned.
1562 */
1563 void sctp_chunk_assign_tsn(struct sctp_chunk *chunk)
1564 {
1565 if (!chunk->has_tsn) {
1566 /* This is the last possible instant to
1567 * assign a TSN.
1568 */
1569 chunk->subh.data_hdr->tsn =
1570 htonl(sctp_association_get_next_tsn(chunk->asoc));
1571 chunk->has_tsn = 1;
1572 }
1573 }
1574
1575 /* Create a CLOSED association to use with an incoming packet. */
1576 struct sctp_association *sctp_make_temp_asoc(const struct sctp_endpoint *ep,
1577 struct sctp_chunk *chunk,
1578 gfp_t gfp)
1579 {
1580 struct sctp_association *asoc;
1581 struct sk_buff *skb;
1582 sctp_scope_t scope;
1583
1584 /* Create the bare association. */
1585 scope = sctp_scope(sctp_source(chunk));
1586 asoc = sctp_association_new(ep, ep->base.sk, scope, gfp);
1587 if (!asoc)
1588 goto nodata;
1589 asoc->temp = 1;
1590 skb = chunk->skb;
1591 /* Create an entry for the source address of the packet. */
1592 SCTP_INPUT_CB(skb)->af->from_skb(&asoc->c.peer_addr, skb, 1);
1593
1594 nodata:
1595 return asoc;
1596 }
1597
1598 /* Build a cookie representing asoc.
1599 * This INCLUDES the param header needed to put the cookie in the INIT ACK.
1600 */
1601 static sctp_cookie_param_t *sctp_pack_cookie(const struct sctp_endpoint *ep,
1602 const struct sctp_association *asoc,
1603 const struct sctp_chunk *init_chunk,
1604 int *cookie_len,
1605 const __u8 *raw_addrs, int addrs_len)
1606 {
1607 sctp_cookie_param_t *retval;
1608 struct sctp_signed_cookie *cookie;
1609 int headersize, bodysize;
1610
1611 /* Header size is static data prior to the actual cookie, including
1612 * any padding.
1613 */
1614 headersize = sizeof(sctp_paramhdr_t) +
1615 (sizeof(struct sctp_signed_cookie) -
1616 sizeof(struct sctp_cookie));
1617 bodysize = sizeof(struct sctp_cookie)
1618 + ntohs(init_chunk->chunk_hdr->length) + addrs_len;
1619
1620 /* Pad out the cookie to a multiple to make the signature
1621 * functions simpler to write.
1622 */
1623 if (bodysize % SCTP_COOKIE_MULTIPLE)
1624 bodysize += SCTP_COOKIE_MULTIPLE
1625 - (bodysize % SCTP_COOKIE_MULTIPLE);
1626 *cookie_len = headersize + bodysize;
1627
1628 /* Clear this memory since we are sending this data structure
1629 * out on the network.
1630 */
1631 retval = kzalloc(*cookie_len, GFP_ATOMIC);
1632 if (!retval)
1633 goto nodata;
1634
1635 cookie = (struct sctp_signed_cookie *) retval->body;
1636
1637 /* Set up the parameter header. */
1638 retval->p.type = SCTP_PARAM_STATE_COOKIE;
1639 retval->p.length = htons(*cookie_len);
1640
1641 /* Copy the cookie part of the association itself. */
1642 cookie->c = asoc->c;
1643 /* Save the raw address list length in the cookie. */
1644 cookie->c.raw_addr_list_len = addrs_len;
1645
1646 /* Remember PR-SCTP capability. */
1647 cookie->c.prsctp_capable = asoc->peer.prsctp_capable;
1648
1649 /* Save adaptation indication in the cookie. */
1650 cookie->c.adaptation_ind = asoc->peer.adaptation_ind;
1651
1652 /* Set an expiration time for the cookie. */
1653 cookie->c.expiration = ktime_add(asoc->cookie_life,
1654 ktime_get_real());
1655
1656 /* Copy the peer's init packet. */
1657 memcpy(&cookie->c.peer_init[0], init_chunk->chunk_hdr,
1658 ntohs(init_chunk->chunk_hdr->length));
1659
1660 /* Copy the raw local address list of the association. */
1661 memcpy((__u8 *)&cookie->c.peer_init[0] +
1662 ntohs(init_chunk->chunk_hdr->length), raw_addrs, addrs_len);
1663
1664 if (sctp_sk(ep->base.sk)->hmac) {
1665 SHASH_DESC_ON_STACK(desc, sctp_sk(ep->base.sk)->hmac);
1666 int err;
1667
1668 /* Sign the message. */
1669 desc->tfm = sctp_sk(ep->base.sk)->hmac;
1670 desc->flags = 0;
1671
1672 err = crypto_shash_setkey(desc->tfm, ep->secret_key,
1673 sizeof(ep->secret_key)) ?:
1674 crypto_shash_digest(desc, (u8 *)&cookie->c, bodysize,
1675 cookie->signature);
1676 shash_desc_zero(desc);
1677 if (err)
1678 goto free_cookie;
1679 }
1680
1681 return retval;
1682
1683 free_cookie:
1684 kfree(retval);
1685 nodata:
1686 *cookie_len = 0;
1687 return NULL;
1688 }
1689
1690 /* Unpack the cookie from COOKIE ECHO chunk, recreating the association. */
1691 struct sctp_association *sctp_unpack_cookie(
1692 const struct sctp_endpoint *ep,
1693 const struct sctp_association *asoc,
1694 struct sctp_chunk *chunk, gfp_t gfp,
1695 int *error, struct sctp_chunk **errp)
1696 {
1697 struct sctp_association *retval = NULL;
1698 struct sctp_signed_cookie *cookie;
1699 struct sctp_cookie *bear_cookie;
1700 int headersize, bodysize, fixed_size;
1701 __u8 *digest = ep->digest;
1702 unsigned int len;
1703 sctp_scope_t scope;
1704 struct sk_buff *skb = chunk->skb;
1705 ktime_t kt;
1706
1707 /* Header size is static data prior to the actual cookie, including
1708 * any padding.
1709 */
1710 headersize = sizeof(sctp_chunkhdr_t) +
1711 (sizeof(struct sctp_signed_cookie) -
1712 sizeof(struct sctp_cookie));
1713 bodysize = ntohs(chunk->chunk_hdr->length) - headersize;
1714 fixed_size = headersize + sizeof(struct sctp_cookie);
1715
1716 /* Verify that the chunk looks like it even has a cookie.
1717 * There must be enough room for our cookie and our peer's
1718 * INIT chunk.
1719 */
1720 len = ntohs(chunk->chunk_hdr->length);
1721 if (len < fixed_size + sizeof(struct sctp_chunkhdr))
1722 goto malformed;
1723
1724 /* Verify that the cookie has been padded out. */
1725 if (bodysize % SCTP_COOKIE_MULTIPLE)
1726 goto malformed;
1727
1728 /* Process the cookie. */
1729 cookie = chunk->subh.cookie_hdr;
1730 bear_cookie = &cookie->c;
1731
1732 if (!sctp_sk(ep->base.sk)->hmac)
1733 goto no_hmac;
1734
1735 /* Check the signature. */
1736 {
1737 SHASH_DESC_ON_STACK(desc, sctp_sk(ep->base.sk)->hmac);
1738 int err;
1739
1740 desc->tfm = sctp_sk(ep->base.sk)->hmac;
1741 desc->flags = 0;
1742
1743 err = crypto_shash_setkey(desc->tfm, ep->secret_key,
1744 sizeof(ep->secret_key)) ?:
1745 crypto_shash_digest(desc, (u8 *)bear_cookie, bodysize,
1746 digest);
1747 shash_desc_zero(desc);
1748
1749 if (err) {
1750 *error = -SCTP_IERROR_NOMEM;
1751 goto fail;
1752 }
1753 }
1754
1755 if (memcmp(digest, cookie->signature, SCTP_SIGNATURE_SIZE)) {
1756 *error = -SCTP_IERROR_BAD_SIG;
1757 goto fail;
1758 }
1759
1760 no_hmac:
1761 /* IG Section 2.35.2:
1762 * 3) Compare the port numbers and the verification tag contained
1763 * within the COOKIE ECHO chunk to the actual port numbers and the
1764 * verification tag within the SCTP common header of the received
1765 * packet. If these values do not match the packet MUST be silently
1766 * discarded,
1767 */
1768 if (ntohl(chunk->sctp_hdr->vtag) != bear_cookie->my_vtag) {
1769 *error = -SCTP_IERROR_BAD_TAG;
1770 goto fail;
1771 }
1772
1773 if (chunk->sctp_hdr->source != bear_cookie->peer_addr.v4.sin_port ||
1774 ntohs(chunk->sctp_hdr->dest) != bear_cookie->my_port) {
1775 *error = -SCTP_IERROR_BAD_PORTS;
1776 goto fail;
1777 }
1778
1779 /* Check to see if the cookie is stale. If there is already
1780 * an association, there is no need to check cookie's expiration
1781 * for init collision case of lost COOKIE ACK.
1782 * If skb has been timestamped, then use the stamp, otherwise
1783 * use current time. This introduces a small possibility that
1784 * that a cookie may be considered expired, but his would only slow
1785 * down the new association establishment instead of every packet.
1786 */
1787 if (sock_flag(ep->base.sk, SOCK_TIMESTAMP))
1788 kt = skb_get_ktime(skb);
1789 else
1790 kt = ktime_get_real();
1791
1792 if (!asoc && ktime_before(bear_cookie->expiration, kt)) {
1793 /*
1794 * Section 3.3.10.3 Stale Cookie Error (3)
1795 *
1796 * Cause of error
1797 * ---------------
1798 * Stale Cookie Error: Indicates the receipt of a valid State
1799 * Cookie that has expired.
1800 */
1801 len = ntohs(chunk->chunk_hdr->length);
1802 *errp = sctp_make_op_error_space(asoc, chunk, len);
1803 if (*errp) {
1804 suseconds_t usecs = ktime_to_us(ktime_sub(kt, bear_cookie->expiration));
1805 __be32 n = htonl(usecs);
1806
1807 sctp_init_cause(*errp, SCTP_ERROR_STALE_COOKIE,
1808 sizeof(n));
1809 sctp_addto_chunk(*errp, sizeof(n), &n);
1810 *error = -SCTP_IERROR_STALE_COOKIE;
1811 } else
1812 *error = -SCTP_IERROR_NOMEM;
1813
1814 goto fail;
1815 }
1816
1817 /* Make a new base association. */
1818 scope = sctp_scope(sctp_source(chunk));
1819 retval = sctp_association_new(ep, ep->base.sk, scope, gfp);
1820 if (!retval) {
1821 *error = -SCTP_IERROR_NOMEM;
1822 goto fail;
1823 }
1824
1825 /* Set up our peer's port number. */
1826 retval->peer.port = ntohs(chunk->sctp_hdr->source);
1827
1828 /* Populate the association from the cookie. */
1829 memcpy(&retval->c, bear_cookie, sizeof(*bear_cookie));
1830
1831 if (sctp_assoc_set_bind_addr_from_cookie(retval, bear_cookie,
1832 GFP_ATOMIC) < 0) {
1833 *error = -SCTP_IERROR_NOMEM;
1834 goto fail;
1835 }
1836
1837 /* Also, add the destination address. */
1838 if (list_empty(&retval->base.bind_addr.address_list)) {
1839 sctp_add_bind_addr(&retval->base.bind_addr, &chunk->dest,
1840 sizeof(chunk->dest), SCTP_ADDR_SRC,
1841 GFP_ATOMIC);
1842 }
1843
1844 retval->next_tsn = retval->c.initial_tsn;
1845 retval->ctsn_ack_point = retval->next_tsn - 1;
1846 retval->addip_serial = retval->c.initial_tsn;
1847 retval->adv_peer_ack_point = retval->ctsn_ack_point;
1848 retval->peer.prsctp_capable = retval->c.prsctp_capable;
1849 retval->peer.adaptation_ind = retval->c.adaptation_ind;
1850
1851 /* The INIT stuff will be done by the side effects. */
1852 return retval;
1853
1854 fail:
1855 if (retval)
1856 sctp_association_free(retval);
1857
1858 return NULL;
1859
1860 malformed:
1861 /* Yikes! The packet is either corrupt or deliberately
1862 * malformed.
1863 */
1864 *error = -SCTP_IERROR_MALFORMED;
1865 goto fail;
1866 }
1867
1868 /********************************************************************
1869 * 3rd Level Abstractions
1870 ********************************************************************/
1871
1872 struct __sctp_missing {
1873 __be32 num_missing;
1874 __be16 type;
1875 } __packed;
1876
1877 /*
1878 * Report a missing mandatory parameter.
1879 */
1880 static int sctp_process_missing_param(const struct sctp_association *asoc,
1881 sctp_param_t paramtype,
1882 struct sctp_chunk *chunk,
1883 struct sctp_chunk **errp)
1884 {
1885 struct __sctp_missing report;
1886 __u16 len;
1887
1888 len = SCTP_PAD4(sizeof(report));
1889
1890 /* Make an ERROR chunk, preparing enough room for
1891 * returning multiple unknown parameters.
1892 */
1893 if (!*errp)
1894 *errp = sctp_make_op_error_space(asoc, chunk, len);
1895
1896 if (*errp) {
1897 report.num_missing = htonl(1);
1898 report.type = paramtype;
1899 sctp_init_cause(*errp, SCTP_ERROR_MISS_PARAM,
1900 sizeof(report));
1901 sctp_addto_chunk(*errp, sizeof(report), &report);
1902 }
1903
1904 /* Stop processing this chunk. */
1905 return 0;
1906 }
1907
1908 /* Report an Invalid Mandatory Parameter. */
1909 static int sctp_process_inv_mandatory(const struct sctp_association *asoc,
1910 struct sctp_chunk *chunk,
1911 struct sctp_chunk **errp)
1912 {
1913 /* Invalid Mandatory Parameter Error has no payload. */
1914
1915 if (!*errp)
1916 *errp = sctp_make_op_error_space(asoc, chunk, 0);
1917
1918 if (*errp)
1919 sctp_init_cause(*errp, SCTP_ERROR_INV_PARAM, 0);
1920
1921 /* Stop processing this chunk. */
1922 return 0;
1923 }
1924
1925 static int sctp_process_inv_paramlength(const struct sctp_association *asoc,
1926 struct sctp_paramhdr *param,
1927 const struct sctp_chunk *chunk,
1928 struct sctp_chunk **errp)
1929 {
1930 /* This is a fatal error. Any accumulated non-fatal errors are
1931 * not reported.
1932 */
1933 if (*errp)
1934 sctp_chunk_free(*errp);
1935
1936 /* Create an error chunk and fill it in with our payload. */
1937 *errp = sctp_make_violation_paramlen(asoc, chunk, param);
1938
1939 return 0;
1940 }
1941
1942
1943 /* Do not attempt to handle the HOST_NAME parm. However, do
1944 * send back an indicator to the peer.
1945 */
1946 static int sctp_process_hn_param(const struct sctp_association *asoc,
1947 union sctp_params param,
1948 struct sctp_chunk *chunk,
1949 struct sctp_chunk **errp)
1950 {
1951 __u16 len = ntohs(param.p->length);
1952
1953 /* Processing of the HOST_NAME parameter will generate an
1954 * ABORT. If we've accumulated any non-fatal errors, they
1955 * would be unrecognized parameters and we should not include
1956 * them in the ABORT.
1957 */
1958 if (*errp)
1959 sctp_chunk_free(*errp);
1960
1961 *errp = sctp_make_op_error_space(asoc, chunk, len);
1962
1963 if (*errp) {
1964 sctp_init_cause(*errp, SCTP_ERROR_DNS_FAILED, len);
1965 sctp_addto_chunk(*errp, len, param.v);
1966 }
1967
1968 /* Stop processing this chunk. */
1969 return 0;
1970 }
1971
1972 static int sctp_verify_ext_param(struct net *net, union sctp_params param)
1973 {
1974 __u16 num_ext = ntohs(param.p->length) - sizeof(sctp_paramhdr_t);
1975 int have_auth = 0;
1976 int have_asconf = 0;
1977 int i;
1978
1979 for (i = 0; i < num_ext; i++) {
1980 switch (param.ext->chunks[i]) {
1981 case SCTP_CID_AUTH:
1982 have_auth = 1;
1983 break;
1984 case SCTP_CID_ASCONF:
1985 case SCTP_CID_ASCONF_ACK:
1986 have_asconf = 1;
1987 break;
1988 }
1989 }
1990
1991 /* ADD-IP Security: The draft requires us to ABORT or ignore the
1992 * INIT/INIT-ACK if ADD-IP is listed, but AUTH is not. Do this
1993 * only if ADD-IP is turned on and we are not backward-compatible
1994 * mode.
1995 */
1996 if (net->sctp.addip_noauth)
1997 return 1;
1998
1999 if (net->sctp.addip_enable && !have_auth && have_asconf)
2000 return 0;
2001
2002 return 1;
2003 }
2004
2005 static void sctp_process_ext_param(struct sctp_association *asoc,
2006 union sctp_params param)
2007 {
2008 struct net *net = sock_net(asoc->base.sk);
2009 __u16 num_ext = ntohs(param.p->length) - sizeof(sctp_paramhdr_t);
2010 int i;
2011
2012 for (i = 0; i < num_ext; i++) {
2013 switch (param.ext->chunks[i]) {
2014 case SCTP_CID_FWD_TSN:
2015 if (asoc->prsctp_enable && !asoc->peer.prsctp_capable)
2016 asoc->peer.prsctp_capable = 1;
2017 break;
2018 case SCTP_CID_AUTH:
2019 /* if the peer reports AUTH, assume that he
2020 * supports AUTH.
2021 */
2022 if (asoc->ep->auth_enable)
2023 asoc->peer.auth_capable = 1;
2024 break;
2025 case SCTP_CID_ASCONF:
2026 case SCTP_CID_ASCONF_ACK:
2027 if (net->sctp.addip_enable)
2028 asoc->peer.asconf_capable = 1;
2029 break;
2030 default:
2031 break;
2032 }
2033 }
2034 }
2035
2036 /* RFC 3.2.1 & the Implementers Guide 2.2.
2037 *
2038 * The Parameter Types are encoded such that the
2039 * highest-order two bits specify the action that must be
2040 * taken if the processing endpoint does not recognize the
2041 * Parameter Type.
2042 *
2043 * 00 - Stop processing this parameter; do not process any further
2044 * parameters within this chunk
2045 *
2046 * 01 - Stop processing this parameter, do not process any further
2047 * parameters within this chunk, and report the unrecognized
2048 * parameter in an 'Unrecognized Parameter' ERROR chunk.
2049 *
2050 * 10 - Skip this parameter and continue processing.
2051 *
2052 * 11 - Skip this parameter and continue processing but
2053 * report the unrecognized parameter in an
2054 * 'Unrecognized Parameter' ERROR chunk.
2055 *
2056 * Return value:
2057 * SCTP_IERROR_NO_ERROR - continue with the chunk
2058 * SCTP_IERROR_ERROR - stop and report an error.
2059 * SCTP_IERROR_NOMEME - out of memory.
2060 */
2061 static sctp_ierror_t sctp_process_unk_param(const struct sctp_association *asoc,
2062 union sctp_params param,
2063 struct sctp_chunk *chunk,
2064 struct sctp_chunk **errp)
2065 {
2066 int retval = SCTP_IERROR_NO_ERROR;
2067
2068 switch (param.p->type & SCTP_PARAM_ACTION_MASK) {
2069 case SCTP_PARAM_ACTION_DISCARD:
2070 retval = SCTP_IERROR_ERROR;
2071 break;
2072 case SCTP_PARAM_ACTION_SKIP:
2073 break;
2074 case SCTP_PARAM_ACTION_DISCARD_ERR:
2075 retval = SCTP_IERROR_ERROR;
2076 /* Fall through */
2077 case SCTP_PARAM_ACTION_SKIP_ERR:
2078 /* Make an ERROR chunk, preparing enough room for
2079 * returning multiple unknown parameters.
2080 */
2081 if (NULL == *errp)
2082 *errp = sctp_make_op_error_fixed(asoc, chunk);
2083
2084 if (*errp) {
2085 if (!sctp_init_cause_fixed(*errp, SCTP_ERROR_UNKNOWN_PARAM,
2086 SCTP_PAD4(ntohs(param.p->length))))
2087 sctp_addto_chunk_fixed(*errp,
2088 SCTP_PAD4(ntohs(param.p->length)),
2089 param.v);
2090 } else {
2091 /* If there is no memory for generating the ERROR
2092 * report as specified, an ABORT will be triggered
2093 * to the peer and the association won't be
2094 * established.
2095 */
2096 retval = SCTP_IERROR_NOMEM;
2097 }
2098 break;
2099 default:
2100 break;
2101 }
2102
2103 return retval;
2104 }
2105
2106 /* Verify variable length parameters
2107 * Return values:
2108 * SCTP_IERROR_ABORT - trigger an ABORT
2109 * SCTP_IERROR_NOMEM - out of memory (abort)
2110 * SCTP_IERROR_ERROR - stop processing, trigger an ERROR
2111 * SCTP_IERROR_NO_ERROR - continue with the chunk
2112 */
2113 static sctp_ierror_t sctp_verify_param(struct net *net,
2114 const struct sctp_endpoint *ep,
2115 const struct sctp_association *asoc,
2116 union sctp_params param,
2117 sctp_cid_t cid,
2118 struct sctp_chunk *chunk,
2119 struct sctp_chunk **err_chunk)
2120 {
2121 struct sctp_hmac_algo_param *hmacs;
2122 int retval = SCTP_IERROR_NO_ERROR;
2123 __u16 n_elt, id = 0;
2124 int i;
2125
2126 /* FIXME - This routine is not looking at each parameter per the
2127 * chunk type, i.e., unrecognized parameters should be further
2128 * identified based on the chunk id.
2129 */
2130
2131 switch (param.p->type) {
2132 case SCTP_PARAM_IPV4_ADDRESS:
2133 case SCTP_PARAM_IPV6_ADDRESS:
2134 case SCTP_PARAM_COOKIE_PRESERVATIVE:
2135 case SCTP_PARAM_SUPPORTED_ADDRESS_TYPES:
2136 case SCTP_PARAM_STATE_COOKIE:
2137 case SCTP_PARAM_HEARTBEAT_INFO:
2138 case SCTP_PARAM_UNRECOGNIZED_PARAMETERS:
2139 case SCTP_PARAM_ECN_CAPABLE:
2140 case SCTP_PARAM_ADAPTATION_LAYER_IND:
2141 break;
2142
2143 case SCTP_PARAM_SUPPORTED_EXT:
2144 if (!sctp_verify_ext_param(net, param))
2145 return SCTP_IERROR_ABORT;
2146 break;
2147
2148 case SCTP_PARAM_SET_PRIMARY:
2149 if (net->sctp.addip_enable)
2150 break;
2151 goto fallthrough;
2152
2153 case SCTP_PARAM_HOST_NAME_ADDRESS:
2154 /* Tell the peer, we won't support this param. */
2155 sctp_process_hn_param(asoc, param, chunk, err_chunk);
2156 retval = SCTP_IERROR_ABORT;
2157 break;
2158
2159 case SCTP_PARAM_FWD_TSN_SUPPORT:
2160 if (ep->prsctp_enable)
2161 break;
2162 goto fallthrough;
2163
2164 case SCTP_PARAM_RANDOM:
2165 if (!ep->auth_enable)
2166 goto fallthrough;
2167
2168 /* SCTP-AUTH: Secion 6.1
2169 * If the random number is not 32 byte long the association
2170 * MUST be aborted. The ABORT chunk SHOULD contain the error
2171 * cause 'Protocol Violation'.
2172 */
2173 if (SCTP_AUTH_RANDOM_LENGTH !=
2174 ntohs(param.p->length) - sizeof(sctp_paramhdr_t)) {
2175 sctp_process_inv_paramlength(asoc, param.p,
2176 chunk, err_chunk);
2177 retval = SCTP_IERROR_ABORT;
2178 }
2179 break;
2180
2181 case SCTP_PARAM_CHUNKS:
2182 if (!ep->auth_enable)
2183 goto fallthrough;
2184
2185 /* SCTP-AUTH: Section 3.2
2186 * The CHUNKS parameter MUST be included once in the INIT or
2187 * INIT-ACK chunk if the sender wants to receive authenticated
2188 * chunks. Its maximum length is 260 bytes.
2189 */
2190 if (260 < ntohs(param.p->length)) {
2191 sctp_process_inv_paramlength(asoc, param.p,
2192 chunk, err_chunk);
2193 retval = SCTP_IERROR_ABORT;
2194 }
2195 break;
2196
2197 case SCTP_PARAM_HMAC_ALGO:
2198 if (!ep->auth_enable)
2199 goto fallthrough;
2200
2201 hmacs = (struct sctp_hmac_algo_param *)param.p;
2202 n_elt = (ntohs(param.p->length) - sizeof(sctp_paramhdr_t)) >> 1;
2203
2204 /* SCTP-AUTH: Section 6.1
2205 * The HMAC algorithm based on SHA-1 MUST be supported and
2206 * included in the HMAC-ALGO parameter.
2207 */
2208 for (i = 0; i < n_elt; i++) {
2209 id = ntohs(hmacs->hmac_ids[i]);
2210
2211 if (id == SCTP_AUTH_HMAC_ID_SHA1)
2212 break;
2213 }
2214
2215 if (id != SCTP_AUTH_HMAC_ID_SHA1) {
2216 sctp_process_inv_paramlength(asoc, param.p, chunk,
2217 err_chunk);
2218 retval = SCTP_IERROR_ABORT;
2219 }
2220 break;
2221 fallthrough:
2222 default:
2223 pr_debug("%s: unrecognized param:%d for chunk:%d\n",
2224 __func__, ntohs(param.p->type), cid);
2225
2226 retval = sctp_process_unk_param(asoc, param, chunk, err_chunk);
2227 break;
2228 }
2229 return retval;
2230 }
2231
2232 /* Verify the INIT packet before we process it. */
2233 int sctp_verify_init(struct net *net, const struct sctp_endpoint *ep,
2234 const struct sctp_association *asoc, sctp_cid_t cid,
2235 sctp_init_chunk_t *peer_init, struct sctp_chunk *chunk,
2236 struct sctp_chunk **errp)
2237 {
2238 union sctp_params param;
2239 bool has_cookie = false;
2240 int result;
2241
2242 /* Check for missing mandatory parameters. Note: Initial TSN is
2243 * also mandatory, but is not checked here since the valid range
2244 * is 0..2**32-1. RFC4960, section 3.3.3.
2245 */
2246 if (peer_init->init_hdr.num_outbound_streams == 0 ||
2247 peer_init->init_hdr.num_inbound_streams == 0 ||
2248 peer_init->init_hdr.init_tag == 0 ||
2249 ntohl(peer_init->init_hdr.a_rwnd) < SCTP_DEFAULT_MINWINDOW)
2250 return sctp_process_inv_mandatory(asoc, chunk, errp);
2251
2252 sctp_walk_params(param, peer_init, init_hdr.params) {
2253 if (param.p->type == SCTP_PARAM_STATE_COOKIE)
2254 has_cookie = true;
2255 }
2256
2257 /* There is a possibility that a parameter length was bad and
2258 * in that case we would have stoped walking the parameters.
2259 * The current param.p would point at the bad one.
2260 * Current consensus on the mailing list is to generate a PROTOCOL
2261 * VIOLATION error. We build the ERROR chunk here and let the normal
2262 * error handling code build and send the packet.
2263 */
2264 if (param.v != (void *)chunk->chunk_end)
2265 return sctp_process_inv_paramlength(asoc, param.p, chunk, errp);
2266
2267 /* The only missing mandatory param possible today is
2268 * the state cookie for an INIT-ACK chunk.
2269 */
2270 if ((SCTP_CID_INIT_ACK == cid) && !has_cookie)
2271 return sctp_process_missing_param(asoc, SCTP_PARAM_STATE_COOKIE,
2272 chunk, errp);
2273
2274 /* Verify all the variable length parameters */
2275 sctp_walk_params(param, peer_init, init_hdr.params) {
2276 result = sctp_verify_param(net, ep, asoc, param, cid,
2277 chunk, errp);
2278 switch (result) {
2279 case SCTP_IERROR_ABORT:
2280 case SCTP_IERROR_NOMEM:
2281 return 0;
2282 case SCTP_IERROR_ERROR:
2283 return 1;
2284 case SCTP_IERROR_NO_ERROR:
2285 default:
2286 break;
2287 }
2288
2289 } /* for (loop through all parameters) */
2290
2291 return 1;
2292 }
2293
2294 /* Unpack the parameters in an INIT packet into an association.
2295 * Returns 0 on failure, else success.
2296 * FIXME: This is an association method.
2297 */
2298 int sctp_process_init(struct sctp_association *asoc, struct sctp_chunk *chunk,
2299 const union sctp_addr *peer_addr,
2300 sctp_init_chunk_t *peer_init, gfp_t gfp)
2301 {
2302 struct net *net = sock_net(asoc->base.sk);
2303 union sctp_params param;
2304 struct sctp_transport *transport;
2305 struct list_head *pos, *temp;
2306 struct sctp_af *af;
2307 union sctp_addr addr;
2308 char *cookie;
2309 int src_match = 0;
2310
2311 /* We must include the address that the INIT packet came from.
2312 * This is the only address that matters for an INIT packet.
2313 * When processing a COOKIE ECHO, we retrieve the from address
2314 * of the INIT from the cookie.
2315 */
2316
2317 /* This implementation defaults to making the first transport
2318 * added as the primary transport. The source address seems to
2319 * be a a better choice than any of the embedded addresses.
2320 */
2321 if (!sctp_assoc_add_peer(asoc, peer_addr, gfp, SCTP_ACTIVE))
2322 goto nomem;
2323
2324 if (sctp_cmp_addr_exact(sctp_source(chunk), peer_addr))
2325 src_match = 1;
2326
2327 /* Process the initialization parameters. */
2328 sctp_walk_params(param, peer_init, init_hdr.params) {
2329 if (!src_match && (param.p->type == SCTP_PARAM_IPV4_ADDRESS ||
2330 param.p->type == SCTP_PARAM_IPV6_ADDRESS)) {
2331 af = sctp_get_af_specific(param_type2af(param.p->type));
2332 af->from_addr_param(&addr, param.addr,
2333 chunk->sctp_hdr->source, 0);
2334 if (sctp_cmp_addr_exact(sctp_source(chunk), &addr))
2335 src_match = 1;
2336 }
2337
2338 if (!sctp_process_param(asoc, param, peer_addr, gfp))
2339 goto clean_up;
2340 }
2341
2342 /* source address of chunk may not match any valid address */
2343 if (!src_match)
2344 goto clean_up;
2345
2346 /* AUTH: After processing the parameters, make sure that we
2347 * have all the required info to potentially do authentications.
2348 */
2349 if (asoc->peer.auth_capable && (!asoc->peer.peer_random ||
2350 !asoc->peer.peer_hmacs))
2351 asoc->peer.auth_capable = 0;
2352
2353 /* In a non-backward compatible mode, if the peer claims
2354 * support for ADD-IP but not AUTH, the ADD-IP spec states
2355 * that we MUST ABORT the association. Section 6. The section
2356 * also give us an option to silently ignore the packet, which
2357 * is what we'll do here.
2358 */
2359 if (!net->sctp.addip_noauth &&
2360 (asoc->peer.asconf_capable && !asoc->peer.auth_capable)) {
2361 asoc->peer.addip_disabled_mask |= (SCTP_PARAM_ADD_IP |
2362 SCTP_PARAM_DEL_IP |
2363 SCTP_PARAM_SET_PRIMARY);
2364 asoc->peer.asconf_capable = 0;
2365 goto clean_up;
2366 }
2367
2368 /* Walk list of transports, removing transports in the UNKNOWN state. */
2369 list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
2370 transport = list_entry(pos, struct sctp_transport, transports);
2371 if (transport->state == SCTP_UNKNOWN) {
2372 sctp_assoc_rm_peer(asoc, transport);
2373 }
2374 }
2375
2376 /* The fixed INIT headers are always in network byte
2377 * order.
2378 */
2379 asoc->peer.i.init_tag =
2380 ntohl(peer_init->init_hdr.init_tag);
2381 asoc->peer.i.a_rwnd =
2382 ntohl(peer_init->init_hdr.a_rwnd);
2383 asoc->peer.i.num_outbound_streams =
2384 ntohs(peer_init->init_hdr.num_outbound_streams);
2385 asoc->peer.i.num_inbound_streams =
2386 ntohs(peer_init->init_hdr.num_inbound_streams);
2387 asoc->peer.i.initial_tsn =
2388 ntohl(peer_init->init_hdr.initial_tsn);
2389
2390 /* Apply the upper bounds for output streams based on peer's
2391 * number of inbound streams.
2392 */
2393 if (asoc->c.sinit_num_ostreams >
2394 ntohs(peer_init->init_hdr.num_inbound_streams)) {
2395 asoc->c.sinit_num_ostreams =
2396 ntohs(peer_init->init_hdr.num_inbound_streams);
2397 }
2398
2399 if (asoc->c.sinit_max_instreams >
2400 ntohs(peer_init->init_hdr.num_outbound_streams)) {
2401 asoc->c.sinit_max_instreams =
2402 ntohs(peer_init->init_hdr.num_outbound_streams);
2403 }
2404
2405 /* Copy Initiation tag from INIT to VT_peer in cookie. */
2406 asoc->c.peer_vtag = asoc->peer.i.init_tag;
2407
2408 /* Peer Rwnd : Current calculated value of the peer's rwnd. */
2409 asoc->peer.rwnd = asoc->peer.i.a_rwnd;
2410
2411 /* Copy cookie in case we need to resend COOKIE-ECHO. */
2412 cookie = asoc->peer.cookie;
2413 if (cookie) {
2414 asoc->peer.cookie = kmemdup(cookie, asoc->peer.cookie_len, gfp);
2415 if (!asoc->peer.cookie)
2416 goto clean_up;
2417 }
2418
2419 /* RFC 2960 7.2.1 The initial value of ssthresh MAY be arbitrarily
2420 * high (for example, implementations MAY use the size of the receiver
2421 * advertised window).
2422 */
2423 list_for_each_entry(transport, &asoc->peer.transport_addr_list,
2424 transports) {
2425 transport->ssthresh = asoc->peer.i.a_rwnd;
2426 }
2427
2428 /* Set up the TSN tracking pieces. */
2429 if (!sctp_tsnmap_init(&asoc->peer.tsn_map, SCTP_TSN_MAP_INITIAL,
2430 asoc->peer.i.initial_tsn, gfp))
2431 goto clean_up;
2432
2433 /* RFC 2960 6.5 Stream Identifier and Stream Sequence Number
2434 *
2435 * The stream sequence number in all the streams shall start
2436 * from 0 when the association is established. Also, when the
2437 * stream sequence number reaches the value 65535 the next
2438 * stream sequence number shall be set to 0.
2439 */
2440
2441 /* Allocate storage for the negotiated streams if it is not a temporary
2442 * association.
2443 */
2444 if (!asoc->temp) {
2445 int error;
2446
2447 asoc->ssnmap = sctp_ssnmap_new(asoc->c.sinit_max_instreams,
2448 asoc->c.sinit_num_ostreams, gfp);
2449 if (!asoc->ssnmap)
2450 goto clean_up;
2451
2452 error = sctp_assoc_set_id(asoc, gfp);
2453 if (error)
2454 goto clean_up;
2455 }
2456
2457 /* ADDIP Section 4.1 ASCONF Chunk Procedures
2458 *
2459 * When an endpoint has an ASCONF signaled change to be sent to the
2460 * remote endpoint it should do the following:
2461 * ...
2462 * A2) A serial number should be assigned to the Chunk. The serial
2463 * number should be a monotonically increasing number. All serial
2464 * numbers are defined to be initialized at the start of the
2465 * association to the same value as the Initial TSN.
2466 */
2467 asoc->peer.addip_serial = asoc->peer.i.initial_tsn - 1;
2468 return 1;
2469
2470 clean_up:
2471 /* Release the transport structures. */
2472 list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
2473 transport = list_entry(pos, struct sctp_transport, transports);
2474 if (transport->state != SCTP_ACTIVE)
2475 sctp_assoc_rm_peer(asoc, transport);
2476 }
2477
2478 nomem:
2479 return 0;
2480 }
2481
2482
2483 /* Update asoc with the option described in param.
2484 *
2485 * RFC2960 3.3.2.1 Optional/Variable Length Parameters in INIT
2486 *
2487 * asoc is the association to update.
2488 * param is the variable length parameter to use for update.
2489 * cid tells us if this is an INIT, INIT ACK or COOKIE ECHO.
2490 * If the current packet is an INIT we want to minimize the amount of
2491 * work we do. In particular, we should not build transport
2492 * structures for the addresses.
2493 */
2494 static int sctp_process_param(struct sctp_association *asoc,
2495 union sctp_params param,
2496 const union sctp_addr *peer_addr,
2497 gfp_t gfp)
2498 {
2499 struct net *net = sock_net(asoc->base.sk);
2500 union sctp_addr addr;
2501 int i;
2502 __u16 sat;
2503 int retval = 1;
2504 sctp_scope_t scope;
2505 u32 stale;
2506 struct sctp_af *af;
2507 union sctp_addr_param *addr_param;
2508 struct sctp_transport *t;
2509 struct sctp_endpoint *ep = asoc->ep;
2510
2511 /* We maintain all INIT parameters in network byte order all the
2512 * time. This allows us to not worry about whether the parameters
2513 * came from a fresh INIT, and INIT ACK, or were stored in a cookie.
2514 */
2515 switch (param.p->type) {
2516 case SCTP_PARAM_IPV6_ADDRESS:
2517 if (PF_INET6 != asoc->base.sk->sk_family)
2518 break;
2519 goto do_addr_param;
2520
2521 case SCTP_PARAM_IPV4_ADDRESS:
2522 /* v4 addresses are not allowed on v6-only socket */
2523 if (ipv6_only_sock(asoc->base.sk))
2524 break;
2525 do_addr_param:
2526 af = sctp_get_af_specific(param_type2af(param.p->type));
2527 af->from_addr_param(&addr, param.addr, htons(asoc->peer.port), 0);
2528 scope = sctp_scope(peer_addr);
2529 if (sctp_in_scope(net, &addr, scope))
2530 if (!sctp_assoc_add_peer(asoc, &addr, gfp, SCTP_UNCONFIRMED))
2531 return 0;
2532 break;
2533
2534 case SCTP_PARAM_COOKIE_PRESERVATIVE:
2535 if (!net->sctp.cookie_preserve_enable)
2536 break;
2537
2538 stale = ntohl(param.life->lifespan_increment);
2539
2540 /* Suggested Cookie Life span increment's unit is msec,
2541 * (1/1000sec).
2542 */
2543 asoc->cookie_life = ktime_add_ms(asoc->cookie_life, stale);
2544 break;
2545
2546 case SCTP_PARAM_HOST_NAME_ADDRESS:
2547 pr_debug("%s: unimplemented SCTP_HOST_NAME_ADDRESS\n", __func__);
2548 break;
2549
2550 case SCTP_PARAM_SUPPORTED_ADDRESS_TYPES:
2551 /* Turn off the default values first so we'll know which
2552 * ones are really set by the peer.
2553 */
2554 asoc->peer.ipv4_address = 0;
2555 asoc->peer.ipv6_address = 0;
2556
2557 /* Assume that peer supports the address family
2558 * by which it sends a packet.
2559 */
2560 if (peer_addr->sa.sa_family == AF_INET6)
2561 asoc->peer.ipv6_address = 1;
2562 else if (peer_addr->sa.sa_family == AF_INET)
2563 asoc->peer.ipv4_address = 1;
2564
2565 /* Cycle through address types; avoid divide by 0. */
2566 sat = ntohs(param.p->length) - sizeof(sctp_paramhdr_t);
2567 if (sat)
2568 sat /= sizeof(__u16);
2569
2570 for (i = 0; i < sat; ++i) {
2571 switch (param.sat->types[i]) {
2572 case SCTP_PARAM_IPV4_ADDRESS:
2573 asoc->peer.ipv4_address = 1;
2574 break;
2575
2576 case SCTP_PARAM_IPV6_ADDRESS:
2577 if (PF_INET6 == asoc->base.sk->sk_family)
2578 asoc->peer.ipv6_address = 1;
2579 break;
2580
2581 case SCTP_PARAM_HOST_NAME_ADDRESS:
2582 asoc->peer.hostname_address = 1;
2583 break;
2584
2585 default: /* Just ignore anything else. */
2586 break;
2587 }
2588 }
2589 break;
2590
2591 case SCTP_PARAM_STATE_COOKIE:
2592 asoc->peer.cookie_len =
2593 ntohs(param.p->length) - sizeof(sctp_paramhdr_t);
2594 asoc->peer.cookie = param.cookie->body;
2595 break;
2596
2597 case SCTP_PARAM_HEARTBEAT_INFO:
2598 /* Would be odd to receive, but it causes no problems. */
2599 break;
2600
2601 case SCTP_PARAM_UNRECOGNIZED_PARAMETERS:
2602 /* Rejected during verify stage. */
2603 break;
2604
2605 case SCTP_PARAM_ECN_CAPABLE:
2606 asoc->peer.ecn_capable = 1;
2607 break;
2608
2609 case SCTP_PARAM_ADAPTATION_LAYER_IND:
2610 asoc->peer.adaptation_ind = ntohl(param.aind->adaptation_ind);
2611 break;
2612
2613 case SCTP_PARAM_SET_PRIMARY:
2614 if (!net->sctp.addip_enable)
2615 goto fall_through;
2616
2617 addr_param = param.v + sizeof(sctp_addip_param_t);
2618
2619 af = sctp_get_af_specific(param_type2af(addr_param->p.type));
2620 if (af == NULL)
2621 break;
2622
2623 af->from_addr_param(&addr, addr_param,
2624 htons(asoc->peer.port), 0);
2625
2626 /* if the address is invalid, we can't process it.
2627 * XXX: see spec for what to do.
2628 */
2629 if (!af->addr_valid(&addr, NULL, NULL))
2630 break;
2631
2632 t = sctp_assoc_lookup_paddr(asoc, &addr);
2633 if (!t)
2634 break;
2635
2636 sctp_assoc_set_primary(asoc, t);
2637 break;
2638
2639 case SCTP_PARAM_SUPPORTED_EXT:
2640 sctp_process_ext_param(asoc, param);
2641 break;
2642
2643 case SCTP_PARAM_FWD_TSN_SUPPORT:
2644 if (asoc->prsctp_enable) {
2645 asoc->peer.prsctp_capable = 1;
2646 break;
2647 }
2648 /* Fall Through */
2649 goto fall_through;
2650
2651 case SCTP_PARAM_RANDOM:
2652 if (!ep->auth_enable)
2653 goto fall_through;
2654
2655 /* Save peer's random parameter */
2656 asoc->peer.peer_random = kmemdup(param.p,
2657 ntohs(param.p->length), gfp);
2658 if (!asoc->peer.peer_random) {
2659 retval = 0;
2660 break;
2661 }
2662 break;
2663
2664 case SCTP_PARAM_HMAC_ALGO:
2665 if (!ep->auth_enable)
2666 goto fall_through;
2667
2668 /* Save peer's HMAC list */
2669 asoc->peer.peer_hmacs = kmemdup(param.p,
2670 ntohs(param.p->length), gfp);
2671 if (!asoc->peer.peer_hmacs) {
2672 retval = 0;
2673 break;
2674 }
2675
2676 /* Set the default HMAC the peer requested*/
2677 sctp_auth_asoc_set_default_hmac(asoc, param.hmac_algo);
2678 break;
2679
2680 case SCTP_PARAM_CHUNKS:
2681 if (!ep->auth_enable)
2682 goto fall_through;
2683
2684 asoc->peer.peer_chunks = kmemdup(param.p,
2685 ntohs(param.p->length), gfp);
2686 if (!asoc->peer.peer_chunks)
2687 retval = 0;
2688 break;
2689 fall_through:
2690 default:
2691 /* Any unrecognized parameters should have been caught
2692 * and handled by sctp_verify_param() which should be
2693 * called prior to this routine. Simply log the error
2694 * here.
2695 */
2696 pr_debug("%s: ignoring param:%d for association:%p.\n",
2697 __func__, ntohs(param.p->type), asoc);
2698 break;
2699 }
2700
2701 return retval;
2702 }
2703
2704 /* Select a new verification tag. */
2705 __u32 sctp_generate_tag(const struct sctp_endpoint *ep)
2706 {
2707 /* I believe that this random number generator complies with RFC1750.
2708 * A tag of 0 is reserved for special cases (e.g. INIT).
2709 */
2710 __u32 x;
2711
2712 do {
2713 get_random_bytes(&x, sizeof(__u32));
2714 } while (x == 0);
2715
2716 return x;
2717 }
2718
2719 /* Select an initial TSN to send during startup. */
2720 __u32 sctp_generate_tsn(const struct sctp_endpoint *ep)
2721 {
2722 __u32 retval;
2723
2724 get_random_bytes(&retval, sizeof(__u32));
2725 return retval;
2726 }
2727
2728 /*
2729 * ADDIP 3.1.1 Address Configuration Change Chunk (ASCONF)
2730 * 0 1 2 3
2731 * 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
2732 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2733 * | Type = 0xC1 | Chunk Flags | Chunk Length |
2734 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2735 * | Serial Number |
2736 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2737 * | Address Parameter |
2738 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2739 * | ASCONF Parameter #1 |
2740 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2741 * \ \
2742 * / .... /
2743 * \ \
2744 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2745 * | ASCONF Parameter #N |
2746 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2747 *
2748 * Address Parameter and other parameter will not be wrapped in this function
2749 */
2750 static struct sctp_chunk *sctp_make_asconf(struct sctp_association *asoc,
2751 union sctp_addr *addr,
2752 int vparam_len)
2753 {
2754 sctp_addiphdr_t asconf;
2755 struct sctp_chunk *retval;
2756 int length = sizeof(asconf) + vparam_len;
2757 union sctp_addr_param addrparam;
2758 int addrlen;
2759 struct sctp_af *af = sctp_get_af_specific(addr->v4.sin_family);
2760
2761 addrlen = af->to_addr_param(addr, &addrparam);
2762 if (!addrlen)
2763 return NULL;
2764 length += addrlen;
2765
2766 /* Create the chunk. */
2767 retval = sctp_make_control(asoc, SCTP_CID_ASCONF, 0, length,
2768 GFP_ATOMIC);
2769 if (!retval)
2770 return NULL;
2771
2772 asconf.serial = htonl(asoc->addip_serial++);
2773
2774 retval->subh.addip_hdr =
2775 sctp_addto_chunk(retval, sizeof(asconf), &asconf);
2776 retval->param_hdr.v =
2777 sctp_addto_chunk(retval, addrlen, &addrparam);
2778
2779 return retval;
2780 }
2781
2782 /* ADDIP
2783 * 3.2.1 Add IP Address
2784 * 0 1 2 3
2785 * 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
2786 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2787 * | Type = 0xC001 | Length = Variable |
2788 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2789 * | ASCONF-Request Correlation ID |
2790 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2791 * | Address Parameter |
2792 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2793 *
2794 * 3.2.2 Delete IP Address
2795 * 0 1 2 3
2796 * 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
2797 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2798 * | Type = 0xC002 | Length = Variable |
2799 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2800 * | ASCONF-Request Correlation ID |
2801 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2802 * | Address Parameter |
2803 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2804 *
2805 */
2806 struct sctp_chunk *sctp_make_asconf_update_ip(struct sctp_association *asoc,
2807 union sctp_addr *laddr,
2808 struct sockaddr *addrs,
2809 int addrcnt,
2810 __be16 flags)
2811 {
2812 sctp_addip_param_t param;
2813 struct sctp_chunk *retval;
2814 union sctp_addr_param addr_param;
2815 union sctp_addr *addr;
2816 void *addr_buf;
2817 struct sctp_af *af;
2818 int paramlen = sizeof(param);
2819 int addr_param_len = 0;
2820 int totallen = 0;
2821 int i;
2822 int del_pickup = 0;
2823
2824 /* Get total length of all the address parameters. */
2825 addr_buf = addrs;
2826 for (i = 0; i < addrcnt; i++) {
2827 addr = addr_buf;
2828 af = sctp_get_af_specific(addr->v4.sin_family);
2829 addr_param_len = af->to_addr_param(addr, &addr_param);
2830
2831 totallen += paramlen;
2832 totallen += addr_param_len;
2833
2834 addr_buf += af->sockaddr_len;
2835 if (asoc->asconf_addr_del_pending && !del_pickup) {
2836 /* reuse the parameter length from the same scope one */
2837 totallen += paramlen;
2838 totallen += addr_param_len;
2839 del_pickup = 1;
2840
2841 pr_debug("%s: picked same-scope del_pending addr, "
2842 "totallen for all addresses is %d\n",
2843 __func__, totallen);
2844 }
2845 }
2846
2847 /* Create an asconf chunk with the required length. */
2848 retval = sctp_make_asconf(asoc, laddr, totallen);
2849 if (!retval)
2850 return NULL;
2851
2852 /* Add the address parameters to the asconf chunk. */
2853 addr_buf = addrs;
2854 for (i = 0; i < addrcnt; i++) {
2855 addr = addr_buf;
2856 af = sctp_get_af_specific(addr->v4.sin_family);
2857 addr_param_len = af->to_addr_param(addr, &addr_param);
2858 param.param_hdr.type = flags;
2859 param.param_hdr.length = htons(paramlen + addr_param_len);
2860 param.crr_id = i;
2861
2862 sctp_addto_chunk(retval, paramlen, &param);
2863 sctp_addto_chunk(retval, addr_param_len, &addr_param);
2864
2865 addr_buf += af->sockaddr_len;
2866 }
2867 if (flags == SCTP_PARAM_ADD_IP && del_pickup) {
2868 addr = asoc->asconf_addr_del_pending;
2869 af = sctp_get_af_specific(addr->v4.sin_family);
2870 addr_param_len = af->to_addr_param(addr, &addr_param);
2871 param.param_hdr.type = SCTP_PARAM_DEL_IP;
2872 param.param_hdr.length = htons(paramlen + addr_param_len);
2873 param.crr_id = i;
2874
2875 sctp_addto_chunk(retval, paramlen, &param);
2876 sctp_addto_chunk(retval, addr_param_len, &addr_param);
2877 }
2878 return retval;
2879 }
2880
2881 /* ADDIP
2882 * 3.2.4 Set Primary IP Address
2883 * 0 1 2 3
2884 * 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
2885 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2886 * | Type =0xC004 | Length = Variable |
2887 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2888 * | ASCONF-Request Correlation ID |
2889 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2890 * | Address Parameter |
2891 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2892 *
2893 * Create an ASCONF chunk with Set Primary IP address parameter.
2894 */
2895 struct sctp_chunk *sctp_make_asconf_set_prim(struct sctp_association *asoc,
2896 union sctp_addr *addr)
2897 {
2898 sctp_addip_param_t param;
2899 struct sctp_chunk *retval;
2900 int len = sizeof(param);
2901 union sctp_addr_param addrparam;
2902 int addrlen;
2903 struct sctp_af *af = sctp_get_af_specific(addr->v4.sin_family);
2904
2905 addrlen = af->to_addr_param(addr, &addrparam);
2906 if (!addrlen)
2907 return NULL;
2908 len += addrlen;
2909
2910 /* Create the chunk and make asconf header. */
2911 retval = sctp_make_asconf(asoc, addr, len);
2912 if (!retval)
2913 return NULL;
2914
2915 param.param_hdr.type = SCTP_PARAM_SET_PRIMARY;
2916 param.param_hdr.length = htons(len);
2917 param.crr_id = 0;
2918
2919 sctp_addto_chunk(retval, sizeof(param), &param);
2920 sctp_addto_chunk(retval, addrlen, &addrparam);
2921
2922 return retval;
2923 }
2924
2925 /* ADDIP 3.1.2 Address Configuration Acknowledgement Chunk (ASCONF-ACK)
2926 * 0 1 2 3
2927 * 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
2928 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2929 * | Type = 0x80 | Chunk Flags | Chunk Length |
2930 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2931 * | Serial Number |
2932 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2933 * | ASCONF Parameter Response#1 |
2934 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2935 * \ \
2936 * / .... /
2937 * \ \
2938 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2939 * | ASCONF Parameter Response#N |
2940 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2941 *
2942 * Create an ASCONF_ACK chunk with enough space for the parameter responses.
2943 */
2944 static struct sctp_chunk *sctp_make_asconf_ack(const struct sctp_association *asoc,
2945 __u32 serial, int vparam_len)
2946 {
2947 sctp_addiphdr_t asconf;
2948 struct sctp_chunk *retval;
2949 int length = sizeof(asconf) + vparam_len;
2950
2951 /* Create the chunk. */
2952 retval = sctp_make_control(asoc, SCTP_CID_ASCONF_ACK, 0, length,
2953 GFP_ATOMIC);
2954 if (!retval)
2955 return NULL;
2956
2957 asconf.serial = htonl(serial);
2958
2959 retval->subh.addip_hdr =
2960 sctp_addto_chunk(retval, sizeof(asconf), &asconf);
2961
2962 return retval;
2963 }
2964
2965 /* Add response parameters to an ASCONF_ACK chunk. */
2966 static void sctp_add_asconf_response(struct sctp_chunk *chunk, __be32 crr_id,
2967 __be16 err_code, sctp_addip_param_t *asconf_param)
2968 {
2969 sctp_addip_param_t ack_param;
2970 sctp_errhdr_t err_param;
2971 int asconf_param_len = 0;
2972 int err_param_len = 0;
2973 __be16 response_type;
2974
2975 if (SCTP_ERROR_NO_ERROR == err_code) {
2976 response_type = SCTP_PARAM_SUCCESS_REPORT;
2977 } else {
2978 response_type = SCTP_PARAM_ERR_CAUSE;
2979 err_param_len = sizeof(err_param);
2980 if (asconf_param)
2981 asconf_param_len =
2982 ntohs(asconf_param->param_hdr.length);
2983 }
2984
2985 /* Add Success Indication or Error Cause Indication parameter. */
2986 ack_param.param_hdr.type = response_type;
2987 ack_param.param_hdr.length = htons(sizeof(ack_param) +
2988 err_param_len +
2989 asconf_param_len);
2990 ack_param.crr_id = crr_id;
2991 sctp_addto_chunk(chunk, sizeof(ack_param), &ack_param);
2992
2993 if (SCTP_ERROR_NO_ERROR == err_code)
2994 return;
2995
2996 /* Add Error Cause parameter. */
2997 err_param.cause = err_code;
2998 err_param.length = htons(err_param_len + asconf_param_len);
2999 sctp_addto_chunk(chunk, err_param_len, &err_param);
3000
3001 /* Add the failed TLV copied from ASCONF chunk. */
3002 if (asconf_param)
3003 sctp_addto_chunk(chunk, asconf_param_len, asconf_param);
3004 }
3005
3006 /* Process a asconf parameter. */
3007 static __be16 sctp_process_asconf_param(struct sctp_association *asoc,
3008 struct sctp_chunk *asconf,
3009 sctp_addip_param_t *asconf_param)
3010 {
3011 struct sctp_transport *peer;
3012 struct sctp_af *af;
3013 union sctp_addr addr;
3014 union sctp_addr_param *addr_param;
3015
3016 addr_param = (void *)asconf_param + sizeof(sctp_addip_param_t);
3017
3018 if (asconf_param->param_hdr.type != SCTP_PARAM_ADD_IP &&
3019 asconf_param->param_hdr.type != SCTP_PARAM_DEL_IP &&
3020 asconf_param->param_hdr.type != SCTP_PARAM_SET_PRIMARY)
3021 return SCTP_ERROR_UNKNOWN_PARAM;
3022
3023 switch (addr_param->p.type) {
3024 case SCTP_PARAM_IPV6_ADDRESS:
3025 if (!asoc->peer.ipv6_address)
3026 return SCTP_ERROR_DNS_FAILED;
3027 break;
3028 case SCTP_PARAM_IPV4_ADDRESS:
3029 if (!asoc->peer.ipv4_address)
3030 return SCTP_ERROR_DNS_FAILED;
3031 break;
3032 default:
3033 return SCTP_ERROR_DNS_FAILED;
3034 }
3035
3036 af = sctp_get_af_specific(param_type2af(addr_param->p.type));
3037 if (unlikely(!af))
3038 return SCTP_ERROR_DNS_FAILED;
3039
3040 af->from_addr_param(&addr, addr_param, htons(asoc->peer.port), 0);
3041
3042 /* ADDIP 4.2.1 This parameter MUST NOT contain a broadcast
3043 * or multicast address.
3044 * (note: wildcard is permitted and requires special handling so
3045 * make sure we check for that)
3046 */
3047 if (!af->is_any(&addr) && !af->addr_valid(&addr, NULL, asconf->skb))
3048 return SCTP_ERROR_DNS_FAILED;
3049
3050 switch (asconf_param->param_hdr.type) {
3051 case SCTP_PARAM_ADD_IP:
3052 /* Section 4.2.1:
3053 * If the address 0.0.0.0 or ::0 is provided, the source
3054 * address of the packet MUST be added.
3055 */
3056 if (af->is_any(&addr))
3057 memcpy(&addr, &asconf->source, sizeof(addr));
3058
3059 /* ADDIP 4.3 D9) If an endpoint receives an ADD IP address
3060 * request and does not have the local resources to add this
3061 * new address to the association, it MUST return an Error
3062 * Cause TLV set to the new error code 'Operation Refused
3063 * Due to Resource Shortage'.
3064 */
3065
3066 peer = sctp_assoc_add_peer(asoc, &addr, GFP_ATOMIC, SCTP_UNCONFIRMED);
3067 if (!peer)
3068 return SCTP_ERROR_RSRC_LOW;
3069
3070 /* Start the heartbeat timer. */
3071 sctp_transport_reset_hb_timer(peer);
3072 asoc->new_transport = peer;
3073 break;
3074 case SCTP_PARAM_DEL_IP:
3075 /* ADDIP 4.3 D7) If a request is received to delete the
3076 * last remaining IP address of a peer endpoint, the receiver
3077 * MUST send an Error Cause TLV with the error cause set to the
3078 * new error code 'Request to Delete Last Remaining IP Address'.
3079 */
3080 if (asoc->peer.transport_count == 1)
3081 return SCTP_ERROR_DEL_LAST_IP;
3082
3083 /* ADDIP 4.3 D8) If a request is received to delete an IP
3084 * address which is also the source address of the IP packet
3085 * which contained the ASCONF chunk, the receiver MUST reject
3086 * this request. To reject the request the receiver MUST send
3087 * an Error Cause TLV set to the new error code 'Request to
3088 * Delete Source IP Address'
3089 */
3090 if (sctp_cmp_addr_exact(&asconf->source, &addr))
3091 return SCTP_ERROR_DEL_SRC_IP;
3092
3093 /* Section 4.2.2
3094 * If the address 0.0.0.0 or ::0 is provided, all
3095 * addresses of the peer except the source address of the
3096 * packet MUST be deleted.
3097 */
3098 if (af->is_any(&addr)) {
3099 sctp_assoc_set_primary(asoc, asconf->transport);
3100 sctp_assoc_del_nonprimary_peers(asoc,
3101 asconf->transport);
3102 return SCTP_ERROR_NO_ERROR;
3103 }
3104
3105 /* If the address is not part of the association, the
3106 * ASCONF-ACK with Error Cause Indication Parameter
3107 * which including cause of Unresolvable Address should
3108 * be sent.
3109 */
3110 peer = sctp_assoc_lookup_paddr(asoc, &addr);
3111 if (!peer)
3112 return SCTP_ERROR_DNS_FAILED;
3113
3114 sctp_assoc_rm_peer(asoc, peer);
3115 break;
3116 case SCTP_PARAM_SET_PRIMARY:
3117 /* ADDIP Section 4.2.4
3118 * If the address 0.0.0.0 or ::0 is provided, the receiver
3119 * MAY mark the source address of the packet as its
3120 * primary.
3121 */
3122 if (af->is_any(&addr))
3123 memcpy(&addr.v4, sctp_source(asconf), sizeof(addr));
3124
3125 peer = sctp_assoc_lookup_paddr(asoc, &addr);
3126 if (!peer)
3127 return SCTP_ERROR_DNS_FAILED;
3128
3129 sctp_assoc_set_primary(asoc, peer);
3130 break;
3131 }
3132
3133 return SCTP_ERROR_NO_ERROR;
3134 }
3135
3136 /* Verify the ASCONF packet before we process it. */
3137 bool sctp_verify_asconf(const struct sctp_association *asoc,
3138 struct sctp_chunk *chunk, bool addr_param_needed,
3139 struct sctp_paramhdr **errp)
3140 {
3141 sctp_addip_chunk_t *addip = (sctp_addip_chunk_t *) chunk->chunk_hdr;
3142 union sctp_params param;
3143 bool addr_param_seen = false;
3144
3145 sctp_walk_params(param, addip, addip_hdr.params) {
3146 size_t length = ntohs(param.p->length);
3147
3148 *errp = param.p;
3149 switch (param.p->type) {
3150 case SCTP_PARAM_ERR_CAUSE:
3151 break;
3152 case SCTP_PARAM_IPV4_ADDRESS:
3153 if (length != sizeof(sctp_ipv4addr_param_t))
3154 return false;
3155 /* ensure there is only one addr param and it's in the
3156 * beginning of addip_hdr params, or we reject it.
3157 */
3158 if (param.v != addip->addip_hdr.params)
3159 return false;
3160 addr_param_seen = true;
3161 break;
3162 case SCTP_PARAM_IPV6_ADDRESS:
3163 if (length != sizeof(sctp_ipv6addr_param_t))
3164 return false;
3165 if (param.v != addip->addip_hdr.params)
3166 return false;
3167 addr_param_seen = true;
3168 break;
3169 case SCTP_PARAM_ADD_IP:
3170 case SCTP_PARAM_DEL_IP:
3171 case SCTP_PARAM_SET_PRIMARY:
3172 /* In ASCONF chunks, these need to be first. */
3173 if (addr_param_needed && !addr_param_seen)
3174 return false;
3175 length = ntohs(param.addip->param_hdr.length);
3176 if (length < sizeof(sctp_addip_param_t) +
3177 sizeof(sctp_paramhdr_t))
3178 return false;
3179 break;
3180 case SCTP_PARAM_SUCCESS_REPORT:
3181 case SCTP_PARAM_ADAPTATION_LAYER_IND:
3182 if (length != sizeof(sctp_addip_param_t))
3183 return false;
3184 break;
3185 default:
3186 /* This is unkown to us, reject! */
3187 return false;
3188 }
3189 }
3190
3191 /* Remaining sanity checks. */
3192 if (addr_param_needed && !addr_param_seen)
3193 return false;
3194 if (!addr_param_needed && addr_param_seen)
3195 return false;
3196 if (param.v != chunk->chunk_end)
3197 return false;
3198
3199 return true;
3200 }
3201
3202 /* Process an incoming ASCONF chunk with the next expected serial no. and
3203 * return an ASCONF_ACK chunk to be sent in response.
3204 */
3205 struct sctp_chunk *sctp_process_asconf(struct sctp_association *asoc,
3206 struct sctp_chunk *asconf)
3207 {
3208 sctp_addip_chunk_t *addip = (sctp_addip_chunk_t *) asconf->chunk_hdr;
3209 bool all_param_pass = true;
3210 union sctp_params param;
3211 sctp_addiphdr_t *hdr;
3212 union sctp_addr_param *addr_param;
3213 sctp_addip_param_t *asconf_param;
3214 struct sctp_chunk *asconf_ack;
3215 __be16 err_code;
3216 int length = 0;
3217 int chunk_len;
3218 __u32 serial;
3219
3220 chunk_len = ntohs(asconf->chunk_hdr->length) - sizeof(sctp_chunkhdr_t);
3221 hdr = (sctp_addiphdr_t *)asconf->skb->data;
3222 serial = ntohl(hdr->serial);
3223
3224 /* Skip the addiphdr and store a pointer to address parameter. */
3225 length = sizeof(sctp_addiphdr_t);
3226 addr_param = (union sctp_addr_param *)(asconf->skb->data + length);
3227 chunk_len -= length;
3228
3229 /* Skip the address parameter and store a pointer to the first
3230 * asconf parameter.
3231 */
3232 length = ntohs(addr_param->p.length);
3233 asconf_param = (void *)addr_param + length;
3234 chunk_len -= length;
3235
3236 /* create an ASCONF_ACK chunk.
3237 * Based on the definitions of parameters, we know that the size of
3238 * ASCONF_ACK parameters are less than or equal to the fourfold of ASCONF
3239 * parameters.
3240 */
3241 asconf_ack = sctp_make_asconf_ack(asoc, serial, chunk_len * 4);
3242 if (!asconf_ack)
3243 goto done;
3244
3245 /* Process the TLVs contained within the ASCONF chunk. */
3246 sctp_walk_params(param, addip, addip_hdr.params) {
3247 /* Skip preceeding address parameters. */
3248 if (param.p->type == SCTP_PARAM_IPV4_ADDRESS ||
3249 param.p->type == SCTP_PARAM_IPV6_ADDRESS)
3250 continue;
3251
3252 err_code = sctp_process_asconf_param(asoc, asconf,
3253 param.addip);
3254 /* ADDIP 4.1 A7)
3255 * If an error response is received for a TLV parameter,
3256 * all TLVs with no response before the failed TLV are
3257 * considered successful if not reported. All TLVs after
3258 * the failed response are considered unsuccessful unless
3259 * a specific success indication is present for the parameter.
3260 */
3261 if (err_code != SCTP_ERROR_NO_ERROR)
3262 all_param_pass = false;
3263 if (!all_param_pass)
3264 sctp_add_asconf_response(asconf_ack, param.addip->crr_id,
3265 err_code, param.addip);
3266
3267 /* ADDIP 4.3 D11) When an endpoint receiving an ASCONF to add
3268 * an IP address sends an 'Out of Resource' in its response, it
3269 * MUST also fail any subsequent add or delete requests bundled
3270 * in the ASCONF.
3271 */
3272 if (err_code == SCTP_ERROR_RSRC_LOW)
3273 goto done;
3274 }
3275 done:
3276 asoc->peer.addip_serial++;
3277
3278 /* If we are sending a new ASCONF_ACK hold a reference to it in assoc
3279 * after freeing the reference to old asconf ack if any.
3280 */
3281 if (asconf_ack) {
3282 sctp_chunk_hold(asconf_ack);
3283 list_add_tail(&asconf_ack->transmitted_list,
3284 &asoc->asconf_ack_list);
3285 }
3286
3287 return asconf_ack;
3288 }
3289
3290 /* Process a asconf parameter that is successfully acked. */
3291 static void sctp_asconf_param_success(struct sctp_association *asoc,
3292 sctp_addip_param_t *asconf_param)
3293 {
3294 struct sctp_af *af;
3295 union sctp_addr addr;
3296 struct sctp_bind_addr *bp = &asoc->base.bind_addr;
3297 union sctp_addr_param *addr_param;
3298 struct sctp_transport *transport;
3299 struct sctp_sockaddr_entry *saddr;
3300
3301 addr_param = (void *)asconf_param + sizeof(sctp_addip_param_t);
3302
3303 /* We have checked the packet before, so we do not check again. */
3304 af = sctp_get_af_specific(param_type2af(addr_param->p.type));
3305 af->from_addr_param(&addr, addr_param, htons(bp->port), 0);
3306
3307 switch (asconf_param->param_hdr.type) {
3308 case SCTP_PARAM_ADD_IP:
3309 /* This is always done in BH context with a socket lock
3310 * held, so the list can not change.
3311 */
3312 local_bh_disable();
3313 list_for_each_entry(saddr, &bp->address_list, list) {
3314 if (sctp_cmp_addr_exact(&saddr->a, &addr))
3315 saddr->state = SCTP_ADDR_SRC;
3316 }
3317 local_bh_enable();
3318 list_for_each_entry(transport, &asoc->peer.transport_addr_list,
3319 transports) {
3320 dst_release(transport->dst);
3321 transport->dst = NULL;
3322 }
3323 break;
3324 case SCTP_PARAM_DEL_IP:
3325 local_bh_disable();
3326 sctp_del_bind_addr(bp, &addr);
3327 if (asoc->asconf_addr_del_pending != NULL &&
3328 sctp_cmp_addr_exact(asoc->asconf_addr_del_pending, &addr)) {
3329 kfree(asoc->asconf_addr_del_pending);
3330 asoc->asconf_addr_del_pending = NULL;
3331 }
3332 local_bh_enable();
3333 list_for_each_entry(transport, &asoc->peer.transport_addr_list,
3334 transports) {
3335 dst_release(transport->dst);
3336 transport->dst = NULL;
3337 }
3338 break;
3339 default:
3340 break;
3341 }
3342 }
3343
3344 /* Get the corresponding ASCONF response error code from the ASCONF_ACK chunk
3345 * for the given asconf parameter. If there is no response for this parameter,
3346 * return the error code based on the third argument 'no_err'.
3347 * ADDIP 4.1
3348 * A7) If an error response is received for a TLV parameter, all TLVs with no
3349 * response before the failed TLV are considered successful if not reported.
3350 * All TLVs after the failed response are considered unsuccessful unless a
3351 * specific success indication is present for the parameter.
3352 */
3353 static __be16 sctp_get_asconf_response(struct sctp_chunk *asconf_ack,
3354 sctp_addip_param_t *asconf_param,
3355 int no_err)
3356 {
3357 sctp_addip_param_t *asconf_ack_param;
3358 sctp_errhdr_t *err_param;
3359 int length;
3360 int asconf_ack_len;
3361 __be16 err_code;
3362
3363 if (no_err)
3364 err_code = SCTP_ERROR_NO_ERROR;
3365 else
3366 err_code = SCTP_ERROR_REQ_REFUSED;
3367
3368 asconf_ack_len = ntohs(asconf_ack->chunk_hdr->length) -
3369 sizeof(sctp_chunkhdr_t);
3370
3371 /* Skip the addiphdr from the asconf_ack chunk and store a pointer to
3372 * the first asconf_ack parameter.
3373 */
3374 length = sizeof(sctp_addiphdr_t);
3375 asconf_ack_param = (sctp_addip_param_t *)(asconf_ack->skb->data +
3376 length);
3377 asconf_ack_len -= length;
3378
3379 while (asconf_ack_len > 0) {
3380 if (asconf_ack_param->crr_id == asconf_param->crr_id) {
3381 switch (asconf_ack_param->param_hdr.type) {
3382 case SCTP_PARAM_SUCCESS_REPORT:
3383 return SCTP_ERROR_NO_ERROR;
3384 case SCTP_PARAM_ERR_CAUSE:
3385 length = sizeof(sctp_addip_param_t);
3386 err_param = (void *)asconf_ack_param + length;
3387 asconf_ack_len -= length;
3388 if (asconf_ack_len > 0)
3389 return err_param->cause;
3390 else
3391 return SCTP_ERROR_INV_PARAM;
3392 break;
3393 default:
3394 return SCTP_ERROR_INV_PARAM;
3395 }
3396 }
3397
3398 length = ntohs(asconf_ack_param->param_hdr.length);
3399 asconf_ack_param = (void *)asconf_ack_param + length;
3400 asconf_ack_len -= length;
3401 }
3402
3403 return err_code;
3404 }
3405
3406 /* Process an incoming ASCONF_ACK chunk against the cached last ASCONF chunk. */
3407 int sctp_process_asconf_ack(struct sctp_association *asoc,
3408 struct sctp_chunk *asconf_ack)
3409 {
3410 struct sctp_chunk *asconf = asoc->addip_last_asconf;
3411 union sctp_addr_param *addr_param;
3412 sctp_addip_param_t *asconf_param;
3413 int length = 0;
3414 int asconf_len = asconf->skb->len;
3415 int all_param_pass = 0;
3416 int no_err = 1;
3417 int retval = 0;
3418 __be16 err_code = SCTP_ERROR_NO_ERROR;
3419
3420 /* Skip the chunkhdr and addiphdr from the last asconf sent and store
3421 * a pointer to address parameter.
3422 */
3423 length = sizeof(sctp_addip_chunk_t);
3424 addr_param = (union sctp_addr_param *)(asconf->skb->data + length);
3425 asconf_len -= length;
3426
3427 /* Skip the address parameter in the last asconf sent and store a
3428 * pointer to the first asconf parameter.
3429 */
3430 length = ntohs(addr_param->p.length);
3431 asconf_param = (void *)addr_param + length;
3432 asconf_len -= length;
3433
3434 /* ADDIP 4.1
3435 * A8) If there is no response(s) to specific TLV parameter(s), and no
3436 * failures are indicated, then all request(s) are considered
3437 * successful.
3438 */
3439 if (asconf_ack->skb->len == sizeof(sctp_addiphdr_t))
3440 all_param_pass = 1;
3441
3442 /* Process the TLVs contained in the last sent ASCONF chunk. */
3443 while (asconf_len > 0) {
3444 if (all_param_pass)
3445 err_code = SCTP_ERROR_NO_ERROR;
3446 else {
3447 err_code = sctp_get_asconf_response(asconf_ack,
3448 asconf_param,
3449 no_err);
3450 if (no_err && (SCTP_ERROR_NO_ERROR != err_code))
3451 no_err = 0;
3452 }
3453
3454 switch (err_code) {
3455 case SCTP_ERROR_NO_ERROR:
3456 sctp_asconf_param_success(asoc, asconf_param);
3457 break;
3458
3459 case SCTP_ERROR_RSRC_LOW:
3460 retval = 1;
3461 break;
3462
3463 case SCTP_ERROR_UNKNOWN_PARAM:
3464 /* Disable sending this type of asconf parameter in
3465 * future.
3466 */
3467 asoc->peer.addip_disabled_mask |=
3468 asconf_param->param_hdr.type;
3469 break;
3470
3471 case SCTP_ERROR_REQ_REFUSED:
3472 case SCTP_ERROR_DEL_LAST_IP:
3473 case SCTP_ERROR_DEL_SRC_IP:
3474 default:
3475 break;
3476 }
3477
3478 /* Skip the processed asconf parameter and move to the next
3479 * one.
3480 */
3481 length = ntohs(asconf_param->param_hdr.length);
3482 asconf_param = (void *)asconf_param + length;
3483 asconf_len -= length;
3484 }
3485
3486 if (no_err && asoc->src_out_of_asoc_ok) {
3487 asoc->src_out_of_asoc_ok = 0;
3488 sctp_transport_immediate_rtx(asoc->peer.primary_path);
3489 }
3490
3491 /* Free the cached last sent asconf chunk. */
3492 list_del_init(&asconf->transmitted_list);
3493 sctp_chunk_free(asconf);
3494 asoc->addip_last_asconf = NULL;
3495
3496 return retval;
3497 }
3498
3499 /* Make a FWD TSN chunk. */
3500 struct sctp_chunk *sctp_make_fwdtsn(const struct sctp_association *asoc,
3501 __u32 new_cum_tsn, size_t nstreams,
3502 struct sctp_fwdtsn_skip *skiplist)
3503 {
3504 struct sctp_chunk *retval = NULL;
3505 struct sctp_fwdtsn_hdr ftsn_hdr;
3506 struct sctp_fwdtsn_skip skip;
3507 size_t hint;
3508 int i;
3509
3510 hint = (nstreams + 1) * sizeof(__u32);
3511
3512 retval = sctp_make_control(asoc, SCTP_CID_FWD_TSN, 0, hint, GFP_ATOMIC);
3513
3514 if (!retval)
3515 return NULL;
3516
3517 ftsn_hdr.new_cum_tsn = htonl(new_cum_tsn);
3518 retval->subh.fwdtsn_hdr =
3519 sctp_addto_chunk(retval, sizeof(ftsn_hdr), &ftsn_hdr);
3520
3521 for (i = 0; i < nstreams; i++) {
3522 skip.stream = skiplist[i].stream;
3523 skip.ssn = skiplist[i].ssn;
3524 sctp_addto_chunk(retval, sizeof(skip), &skip);
3525 }
3526
3527 return retval;
3528 }
Linux with added FPC-III support