ARM: 6668/1: ptrace: remove single-step emulation code
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / net / sctp / sm_make_chunk.c
blob2cc46f0962ca37b63e398c633f794c5986977095
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.
7 * This file is part of the SCTP kernel implementation
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.
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.
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.
25 * You should have received a copy of the GNU General Public License
26 * along with GNU CC; see the file COPYING. If not, write to
27 * the Free Software Foundation, 59 Temple Place - Suite 330,
28 * Boston, MA 02111-1307, USA.
30 * Please send any bug reports or fixes you make to the
31 * email address(es):
32 * lksctp developers <lksctp-developers@lists.sourceforge.net>
34 * Or submit a bug report through the following website:
35 * http://www.sf.net/projects/lksctp
37 * Written or modified by:
38 * La Monte H.P. Yarroll <piggy@acm.org>
39 * Karl Knutson <karl@athena.chicago.il.us>
40 * C. Robin <chris@hundredacre.ac.uk>
41 * Jon Grimm <jgrimm@us.ibm.com>
42 * Xingang Guo <xingang.guo@intel.com>
43 * Dajiang Zhang <dajiang.zhang@nokia.com>
44 * Sridhar Samudrala <sri@us.ibm.com>
45 * Daisy Chang <daisyc@us.ibm.com>
46 * Ardelle Fan <ardelle.fan@intel.com>
47 * Kevin Gao <kevin.gao@intel.com>
49 * Any bugs reported given to us we will try to fix... any fixes shared will
50 * be incorporated into the next SCTP release.
53 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
55 #include <linux/types.h>
56 #include <linux/kernel.h>
57 #include <linux/ip.h>
58 #include <linux/ipv6.h>
59 #include <linux/net.h>
60 #include <linux/inet.h>
61 #include <linux/scatterlist.h>
62 #include <linux/crypto.h>
63 #include <linux/slab.h>
64 #include <net/sock.h>
66 #include <linux/skbuff.h>
67 #include <linux/random.h> /* for get_random_bytes */
68 #include <net/sctp/sctp.h>
69 #include <net/sctp/sm.h>
71 SCTP_STATIC
72 struct sctp_chunk *sctp_make_chunk(const struct sctp_association *asoc,
73 __u8 type, __u8 flags, int paylen);
74 static sctp_cookie_param_t *sctp_pack_cookie(const struct sctp_endpoint *ep,
75 const struct sctp_association *asoc,
76 const struct sctp_chunk *init_chunk,
77 int *cookie_len,
78 const __u8 *raw_addrs, int addrs_len);
79 static int sctp_process_param(struct sctp_association *asoc,
80 union sctp_params param,
81 const union sctp_addr *peer_addr,
82 gfp_t gfp);
83 static void *sctp_addto_param(struct sctp_chunk *chunk, int len,
84 const void *data);
86 /* What was the inbound interface for this chunk? */
87 int sctp_chunk_iif(const struct sctp_chunk *chunk)
89 struct sctp_af *af;
90 int iif = 0;
92 af = sctp_get_af_specific(ipver2af(ip_hdr(chunk->skb)->version));
93 if (af)
94 iif = af->skb_iif(chunk->skb);
96 return iif;
99 /* RFC 2960 3.3.2 Initiation (INIT) (1)
101 * Note 2: The ECN capable field is reserved for future use of
102 * Explicit Congestion Notification.
104 static const struct sctp_paramhdr ecap_param = {
105 SCTP_PARAM_ECN_CAPABLE,
106 cpu_to_be16(sizeof(struct sctp_paramhdr)),
108 static const struct sctp_paramhdr prsctp_param = {
109 SCTP_PARAM_FWD_TSN_SUPPORT,
110 cpu_to_be16(sizeof(struct sctp_paramhdr)),
113 /* A helper to initialize an op error inside a
114 * provided chunk, as most cause codes will be embedded inside an
115 * abort chunk.
117 void sctp_init_cause(struct sctp_chunk *chunk, __be16 cause_code,
118 size_t paylen)
120 sctp_errhdr_t err;
121 __u16 len;
123 /* Cause code constants are now defined in network order. */
124 err.cause = cause_code;
125 len = sizeof(sctp_errhdr_t) + paylen;
126 err.length = htons(len);
127 chunk->subh.err_hdr = sctp_addto_chunk(chunk, sizeof(sctp_errhdr_t), &err);
130 /* A helper to initialize an op error inside a
131 * provided chunk, as most cause codes will be embedded inside an
132 * abort chunk. Differs from sctp_init_cause in that it won't oops
133 * if there isn't enough space in the op error chunk
135 int sctp_init_cause_fixed(struct sctp_chunk *chunk, __be16 cause_code,
136 size_t paylen)
138 sctp_errhdr_t err;
139 __u16 len;
141 /* Cause code constants are now defined in network order. */
142 err.cause = cause_code;
143 len = sizeof(sctp_errhdr_t) + paylen;
144 err.length = htons(len);
146 if (skb_tailroom(chunk->skb) < len)
147 return -ENOSPC;
148 chunk->subh.err_hdr = sctp_addto_chunk_fixed(chunk,
149 sizeof(sctp_errhdr_t),
150 &err);
151 return 0;
153 /* 3.3.2 Initiation (INIT) (1)
155 * This chunk is used to initiate a SCTP association between two
156 * endpoints. The format of the INIT chunk is shown below:
158 * 0 1 2 3
159 * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
160 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
161 * | Type = 1 | Chunk Flags | Chunk Length |
162 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
163 * | Initiate Tag |
164 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
165 * | Advertised Receiver Window Credit (a_rwnd) |
166 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
167 * | Number of Outbound Streams | Number of Inbound Streams |
168 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
169 * | Initial TSN |
170 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
171 * \ \
172 * / Optional/Variable-Length Parameters /
173 * \ \
174 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
177 * The INIT chunk contains the following parameters. Unless otherwise
178 * noted, each parameter MUST only be included once in the INIT chunk.
180 * Fixed Parameters Status
181 * ----------------------------------------------
182 * Initiate Tag Mandatory
183 * Advertised Receiver Window Credit Mandatory
184 * Number of Outbound Streams Mandatory
185 * Number of Inbound Streams Mandatory
186 * Initial TSN Mandatory
188 * Variable Parameters Status Type Value
189 * -------------------------------------------------------------
190 * IPv4 Address (Note 1) Optional 5
191 * IPv6 Address (Note 1) Optional 6
192 * Cookie Preservative Optional 9
193 * Reserved for ECN Capable (Note 2) Optional 32768 (0x8000)
194 * Host Name Address (Note 3) Optional 11
195 * Supported Address Types (Note 4) Optional 12
197 struct sctp_chunk *sctp_make_init(const struct sctp_association *asoc,
198 const struct sctp_bind_addr *bp,
199 gfp_t gfp, int vparam_len)
201 sctp_inithdr_t init;
202 union sctp_params addrs;
203 size_t chunksize;
204 struct sctp_chunk *retval = NULL;
205 int num_types, addrs_len = 0;
206 struct sctp_sock *sp;
207 sctp_supported_addrs_param_t sat;
208 __be16 types[2];
209 sctp_adaptation_ind_param_t aiparam;
210 sctp_supported_ext_param_t ext_param;
211 int num_ext = 0;
212 __u8 extensions[3];
213 sctp_paramhdr_t *auth_chunks = NULL,
214 *auth_hmacs = NULL;
216 /* RFC 2960 3.3.2 Initiation (INIT) (1)
218 * Note 1: The INIT chunks can contain multiple addresses that
219 * can be IPv4 and/or IPv6 in any combination.
221 retval = NULL;
223 /* Convert the provided bind address list to raw format. */
224 addrs = sctp_bind_addrs_to_raw(bp, &addrs_len, gfp);
226 init.init_tag = htonl(asoc->c.my_vtag);
227 init.a_rwnd = htonl(asoc->rwnd);
228 init.num_outbound_streams = htons(asoc->c.sinit_num_ostreams);
229 init.num_inbound_streams = htons(asoc->c.sinit_max_instreams);
230 init.initial_tsn = htonl(asoc->c.initial_tsn);
232 /* How many address types are needed? */
233 sp = sctp_sk(asoc->base.sk);
234 num_types = sp->pf->supported_addrs(sp, types);
236 chunksize = sizeof(init) + addrs_len;
237 chunksize += WORD_ROUND(SCTP_SAT_LEN(num_types));
238 chunksize += sizeof(ecap_param);
240 if (sctp_prsctp_enable)
241 chunksize += sizeof(prsctp_param);
243 /* ADDIP: Section 4.2.7:
244 * An implementation supporting this extension [ADDIP] MUST list
245 * the ASCONF,the ASCONF-ACK, and the AUTH chunks in its INIT and
246 * INIT-ACK parameters.
248 if (sctp_addip_enable) {
249 extensions[num_ext] = SCTP_CID_ASCONF;
250 extensions[num_ext+1] = SCTP_CID_ASCONF_ACK;
251 num_ext += 2;
254 if (sp->adaptation_ind)
255 chunksize += sizeof(aiparam);
257 chunksize += vparam_len;
259 /* Account for AUTH related parameters */
260 if (sctp_auth_enable) {
261 /* Add random parameter length*/
262 chunksize += sizeof(asoc->c.auth_random);
264 /* Add HMACS parameter length if any were defined */
265 auth_hmacs = (sctp_paramhdr_t *)asoc->c.auth_hmacs;
266 if (auth_hmacs->length)
267 chunksize += WORD_ROUND(ntohs(auth_hmacs->length));
268 else
269 auth_hmacs = NULL;
271 /* Add CHUNKS parameter length */
272 auth_chunks = (sctp_paramhdr_t *)asoc->c.auth_chunks;
273 if (auth_chunks->length)
274 chunksize += WORD_ROUND(ntohs(auth_chunks->length));
275 else
276 auth_chunks = NULL;
278 extensions[num_ext] = SCTP_CID_AUTH;
279 num_ext += 1;
282 /* If we have any extensions to report, account for that */
283 if (num_ext)
284 chunksize += WORD_ROUND(sizeof(sctp_supported_ext_param_t) +
285 num_ext);
287 /* RFC 2960 3.3.2 Initiation (INIT) (1)
289 * Note 3: An INIT chunk MUST NOT contain more than one Host
290 * Name address parameter. Moreover, the sender of the INIT
291 * MUST NOT combine any other address types with the Host Name
292 * address in the INIT. The receiver of INIT MUST ignore any
293 * other address types if the Host Name address parameter is
294 * present in the received INIT chunk.
296 * PLEASE DO NOT FIXME [This version does not support Host Name.]
299 retval = sctp_make_chunk(asoc, SCTP_CID_INIT, 0, chunksize);
300 if (!retval)
301 goto nodata;
303 retval->subh.init_hdr =
304 sctp_addto_chunk(retval, sizeof(init), &init);
305 retval->param_hdr.v =
306 sctp_addto_chunk(retval, addrs_len, addrs.v);
308 /* RFC 2960 3.3.2 Initiation (INIT) (1)
310 * Note 4: This parameter, when present, specifies all the
311 * address types the sending endpoint can support. The absence
312 * of this parameter indicates that the sending endpoint can
313 * support any address type.
315 sat.param_hdr.type = SCTP_PARAM_SUPPORTED_ADDRESS_TYPES;
316 sat.param_hdr.length = htons(SCTP_SAT_LEN(num_types));
317 sctp_addto_chunk(retval, sizeof(sat), &sat);
318 sctp_addto_chunk(retval, num_types * sizeof(__u16), &types);
320 sctp_addto_chunk(retval, sizeof(ecap_param), &ecap_param);
322 /* Add the supported extensions parameter. Be nice and add this
323 * fist before addiding the parameters for the extensions themselves
325 if (num_ext) {
326 ext_param.param_hdr.type = SCTP_PARAM_SUPPORTED_EXT;
327 ext_param.param_hdr.length =
328 htons(sizeof(sctp_supported_ext_param_t) + num_ext);
329 sctp_addto_chunk(retval, sizeof(sctp_supported_ext_param_t),
330 &ext_param);
331 sctp_addto_param(retval, num_ext, extensions);
334 if (sctp_prsctp_enable)
335 sctp_addto_chunk(retval, sizeof(prsctp_param), &prsctp_param);
337 if (sp->adaptation_ind) {
338 aiparam.param_hdr.type = SCTP_PARAM_ADAPTATION_LAYER_IND;
339 aiparam.param_hdr.length = htons(sizeof(aiparam));
340 aiparam.adaptation_ind = htonl(sp->adaptation_ind);
341 sctp_addto_chunk(retval, sizeof(aiparam), &aiparam);
344 /* Add SCTP-AUTH chunks to the parameter list */
345 if (sctp_auth_enable) {
346 sctp_addto_chunk(retval, sizeof(asoc->c.auth_random),
347 asoc->c.auth_random);
348 if (auth_hmacs)
349 sctp_addto_chunk(retval, ntohs(auth_hmacs->length),
350 auth_hmacs);
351 if (auth_chunks)
352 sctp_addto_chunk(retval, ntohs(auth_chunks->length),
353 auth_chunks);
355 nodata:
356 kfree(addrs.v);
357 return retval;
360 struct sctp_chunk *sctp_make_init_ack(const struct sctp_association *asoc,
361 const struct sctp_chunk *chunk,
362 gfp_t gfp, int unkparam_len)
364 sctp_inithdr_t initack;
365 struct sctp_chunk *retval;
366 union sctp_params addrs;
367 struct sctp_sock *sp;
368 int addrs_len;
369 sctp_cookie_param_t *cookie;
370 int cookie_len;
371 size_t chunksize;
372 sctp_adaptation_ind_param_t aiparam;
373 sctp_supported_ext_param_t ext_param;
374 int num_ext = 0;
375 __u8 extensions[3];
376 sctp_paramhdr_t *auth_chunks = NULL,
377 *auth_hmacs = NULL,
378 *auth_random = NULL;
380 retval = NULL;
382 /* Note: there may be no addresses to embed. */
383 addrs = sctp_bind_addrs_to_raw(&asoc->base.bind_addr, &addrs_len, gfp);
385 initack.init_tag = htonl(asoc->c.my_vtag);
386 initack.a_rwnd = htonl(asoc->rwnd);
387 initack.num_outbound_streams = htons(asoc->c.sinit_num_ostreams);
388 initack.num_inbound_streams = htons(asoc->c.sinit_max_instreams);
389 initack.initial_tsn = htonl(asoc->c.initial_tsn);
391 /* FIXME: We really ought to build the cookie right
392 * into the packet instead of allocating more fresh memory.
394 cookie = sctp_pack_cookie(asoc->ep, asoc, chunk, &cookie_len,
395 addrs.v, addrs_len);
396 if (!cookie)
397 goto nomem_cookie;
399 /* Calculate the total size of allocation, include the reserved
400 * space for reporting unknown parameters if it is specified.
402 sp = sctp_sk(asoc->base.sk);
403 chunksize = sizeof(initack) + addrs_len + cookie_len + unkparam_len;
405 /* Tell peer that we'll do ECN only if peer advertised such cap. */
406 if (asoc->peer.ecn_capable)
407 chunksize += sizeof(ecap_param);
409 if (asoc->peer.prsctp_capable)
410 chunksize += sizeof(prsctp_param);
412 if (asoc->peer.asconf_capable) {
413 extensions[num_ext] = SCTP_CID_ASCONF;
414 extensions[num_ext+1] = SCTP_CID_ASCONF_ACK;
415 num_ext += 2;
418 if (sp->adaptation_ind)
419 chunksize += sizeof(aiparam);
421 if (asoc->peer.auth_capable) {
422 auth_random = (sctp_paramhdr_t *)asoc->c.auth_random;
423 chunksize += ntohs(auth_random->length);
425 auth_hmacs = (sctp_paramhdr_t *)asoc->c.auth_hmacs;
426 if (auth_hmacs->length)
427 chunksize += WORD_ROUND(ntohs(auth_hmacs->length));
428 else
429 auth_hmacs = NULL;
431 auth_chunks = (sctp_paramhdr_t *)asoc->c.auth_chunks;
432 if (auth_chunks->length)
433 chunksize += WORD_ROUND(ntohs(auth_chunks->length));
434 else
435 auth_chunks = NULL;
437 extensions[num_ext] = SCTP_CID_AUTH;
438 num_ext += 1;
441 if (num_ext)
442 chunksize += WORD_ROUND(sizeof(sctp_supported_ext_param_t) +
443 num_ext);
445 /* Now allocate and fill out the chunk. */
446 retval = sctp_make_chunk(asoc, SCTP_CID_INIT_ACK, 0, chunksize);
447 if (!retval)
448 goto nomem_chunk;
450 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
452 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
453 * HEARTBEAT ACK, * etc.) to the same destination transport
454 * address from which it received the DATA or control chunk
455 * to which it is replying.
457 * [INIT ACK back to where the INIT came from.]
459 retval->transport = chunk->transport;
461 retval->subh.init_hdr =
462 sctp_addto_chunk(retval, sizeof(initack), &initack);
463 retval->param_hdr.v = sctp_addto_chunk(retval, addrs_len, addrs.v);
464 sctp_addto_chunk(retval, cookie_len, cookie);
465 if (asoc->peer.ecn_capable)
466 sctp_addto_chunk(retval, sizeof(ecap_param), &ecap_param);
467 if (num_ext) {
468 ext_param.param_hdr.type = SCTP_PARAM_SUPPORTED_EXT;
469 ext_param.param_hdr.length =
470 htons(sizeof(sctp_supported_ext_param_t) + num_ext);
471 sctp_addto_chunk(retval, sizeof(sctp_supported_ext_param_t),
472 &ext_param);
473 sctp_addto_param(retval, num_ext, extensions);
475 if (asoc->peer.prsctp_capable)
476 sctp_addto_chunk(retval, sizeof(prsctp_param), &prsctp_param);
478 if (sp->adaptation_ind) {
479 aiparam.param_hdr.type = SCTP_PARAM_ADAPTATION_LAYER_IND;
480 aiparam.param_hdr.length = htons(sizeof(aiparam));
481 aiparam.adaptation_ind = htonl(sp->adaptation_ind);
482 sctp_addto_chunk(retval, sizeof(aiparam), &aiparam);
485 if (asoc->peer.auth_capable) {
486 sctp_addto_chunk(retval, ntohs(auth_random->length),
487 auth_random);
488 if (auth_hmacs)
489 sctp_addto_chunk(retval, ntohs(auth_hmacs->length),
490 auth_hmacs);
491 if (auth_chunks)
492 sctp_addto_chunk(retval, ntohs(auth_chunks->length),
493 auth_chunks);
496 /* We need to remove the const qualifier at this point. */
497 retval->asoc = (struct sctp_association *) asoc;
499 nomem_chunk:
500 kfree(cookie);
501 nomem_cookie:
502 kfree(addrs.v);
503 return retval;
506 /* 3.3.11 Cookie Echo (COOKIE ECHO) (10):
508 * This chunk is used only during the initialization of an association.
509 * It is sent by the initiator of an association to its peer to complete
510 * the initialization process. This chunk MUST precede any DATA chunk
511 * sent within the association, but MAY be bundled with one or more DATA
512 * chunks in the same packet.
514 * 0 1 2 3
515 * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
516 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
517 * | Type = 10 |Chunk Flags | Length |
518 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
519 * / Cookie /
520 * \ \
521 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
523 * Chunk Flags: 8 bit
525 * Set to zero on transmit and ignored on receipt.
527 * Length: 16 bits (unsigned integer)
529 * Set to the size of the chunk in bytes, including the 4 bytes of
530 * the chunk header and the size of the Cookie.
532 * Cookie: variable size
534 * This field must contain the exact cookie received in the
535 * State Cookie parameter from the previous INIT ACK.
537 * An implementation SHOULD make the cookie as small as possible
538 * to insure interoperability.
540 struct sctp_chunk *sctp_make_cookie_echo(const struct sctp_association *asoc,
541 const struct sctp_chunk *chunk)
543 struct sctp_chunk *retval;
544 void *cookie;
545 int cookie_len;
547 cookie = asoc->peer.cookie;
548 cookie_len = asoc->peer.cookie_len;
550 /* Build a cookie echo chunk. */
551 retval = sctp_make_chunk(asoc, SCTP_CID_COOKIE_ECHO, 0, cookie_len);
552 if (!retval)
553 goto nodata;
554 retval->subh.cookie_hdr =
555 sctp_addto_chunk(retval, cookie_len, cookie);
557 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
559 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
560 * HEARTBEAT ACK, * etc.) to the same destination transport
561 * address from which it * received the DATA or control chunk
562 * to which it is replying.
564 * [COOKIE ECHO back to where the INIT ACK came from.]
566 if (chunk)
567 retval->transport = chunk->transport;
569 nodata:
570 return retval;
573 /* 3.3.12 Cookie Acknowledgement (COOKIE ACK) (11):
575 * This chunk is used only during the initialization of an
576 * association. It is used to acknowledge the receipt of a COOKIE
577 * ECHO chunk. This chunk MUST precede any DATA or SACK chunk sent
578 * within the association, but MAY be bundled with one or more DATA
579 * chunks or SACK chunk in the same SCTP packet.
581 * 0 1 2 3
582 * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
583 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
584 * | Type = 11 |Chunk Flags | Length = 4 |
585 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
587 * Chunk Flags: 8 bits
589 * Set to zero on transmit and ignored on receipt.
591 struct sctp_chunk *sctp_make_cookie_ack(const struct sctp_association *asoc,
592 const struct sctp_chunk *chunk)
594 struct sctp_chunk *retval;
596 retval = sctp_make_chunk(asoc, SCTP_CID_COOKIE_ACK, 0, 0);
598 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
600 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
601 * HEARTBEAT ACK, * etc.) to the same destination transport
602 * address from which it * received the DATA or control chunk
603 * to which it is replying.
605 * [COOKIE ACK back to where the COOKIE ECHO came from.]
607 if (retval && chunk)
608 retval->transport = chunk->transport;
610 return retval;
614 * Appendix A: Explicit Congestion Notification:
615 * CWR:
617 * RFC 2481 details a specific bit for a sender to send in the header of
618 * its next outbound TCP segment to indicate to its peer that it has
619 * reduced its congestion window. This is termed the CWR bit. For
620 * SCTP the same indication is made by including the CWR chunk.
621 * This chunk contains one data element, i.e. the TSN number that
622 * was sent in the ECNE chunk. This element represents the lowest
623 * TSN number in the datagram that was originally marked with the
624 * CE bit.
626 * 0 1 2 3
627 * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
628 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
629 * | Chunk Type=13 | Flags=00000000| Chunk Length = 8 |
630 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
631 * | Lowest TSN Number |
632 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
634 * Note: The CWR is considered a Control chunk.
636 struct sctp_chunk *sctp_make_cwr(const struct sctp_association *asoc,
637 const __u32 lowest_tsn,
638 const struct sctp_chunk *chunk)
640 struct sctp_chunk *retval;
641 sctp_cwrhdr_t cwr;
643 cwr.lowest_tsn = htonl(lowest_tsn);
644 retval = sctp_make_chunk(asoc, SCTP_CID_ECN_CWR, 0,
645 sizeof(sctp_cwrhdr_t));
647 if (!retval)
648 goto nodata;
650 retval->subh.ecn_cwr_hdr =
651 sctp_addto_chunk(retval, sizeof(cwr), &cwr);
653 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
655 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
656 * HEARTBEAT ACK, * etc.) to the same destination transport
657 * address from which it * received the DATA or control chunk
658 * to which it is replying.
660 * [Report a reduced congestion window back to where the ECNE
661 * came from.]
663 if (chunk)
664 retval->transport = chunk->transport;
666 nodata:
667 return retval;
670 /* Make an ECNE chunk. This is a congestion experienced report. */
671 struct sctp_chunk *sctp_make_ecne(const struct sctp_association *asoc,
672 const __u32 lowest_tsn)
674 struct sctp_chunk *retval;
675 sctp_ecnehdr_t ecne;
677 ecne.lowest_tsn = htonl(lowest_tsn);
678 retval = sctp_make_chunk(asoc, SCTP_CID_ECN_ECNE, 0,
679 sizeof(sctp_ecnehdr_t));
680 if (!retval)
681 goto nodata;
682 retval->subh.ecne_hdr =
683 sctp_addto_chunk(retval, sizeof(ecne), &ecne);
685 nodata:
686 return retval;
689 /* Make a DATA chunk for the given association from the provided
690 * parameters. However, do not populate the data payload.
692 struct sctp_chunk *sctp_make_datafrag_empty(struct sctp_association *asoc,
693 const struct sctp_sndrcvinfo *sinfo,
694 int data_len, __u8 flags, __u16 ssn)
696 struct sctp_chunk *retval;
697 struct sctp_datahdr dp;
698 int chunk_len;
700 /* We assign the TSN as LATE as possible, not here when
701 * creating the chunk.
703 dp.tsn = 0;
704 dp.stream = htons(sinfo->sinfo_stream);
705 dp.ppid = sinfo->sinfo_ppid;
707 /* Set the flags for an unordered send. */
708 if (sinfo->sinfo_flags & SCTP_UNORDERED) {
709 flags |= SCTP_DATA_UNORDERED;
710 dp.ssn = 0;
711 } else
712 dp.ssn = htons(ssn);
714 chunk_len = sizeof(dp) + data_len;
715 retval = sctp_make_chunk(asoc, SCTP_CID_DATA, flags, chunk_len);
716 if (!retval)
717 goto nodata;
719 retval->subh.data_hdr = sctp_addto_chunk(retval, sizeof(dp), &dp);
720 memcpy(&retval->sinfo, sinfo, sizeof(struct sctp_sndrcvinfo));
722 nodata:
723 return retval;
726 /* Create a selective ackowledgement (SACK) for the given
727 * association. This reports on which TSN's we've seen to date,
728 * including duplicates and gaps.
730 struct sctp_chunk *sctp_make_sack(const struct sctp_association *asoc)
732 struct sctp_chunk *retval;
733 struct sctp_sackhdr sack;
734 int len;
735 __u32 ctsn;
736 __u16 num_gabs, num_dup_tsns;
737 struct sctp_tsnmap *map = (struct sctp_tsnmap *)&asoc->peer.tsn_map;
738 struct sctp_gap_ack_block gabs[SCTP_MAX_GABS];
740 memset(gabs, 0, sizeof(gabs));
741 ctsn = sctp_tsnmap_get_ctsn(map);
742 SCTP_DEBUG_PRINTK("sackCTSNAck sent: 0x%x.\n", ctsn);
744 /* How much room is needed in the chunk? */
745 num_gabs = sctp_tsnmap_num_gabs(map, gabs);
746 num_dup_tsns = sctp_tsnmap_num_dups(map);
748 /* Initialize the SACK header. */
749 sack.cum_tsn_ack = htonl(ctsn);
750 sack.a_rwnd = htonl(asoc->a_rwnd);
751 sack.num_gap_ack_blocks = htons(num_gabs);
752 sack.num_dup_tsns = htons(num_dup_tsns);
754 len = sizeof(sack)
755 + sizeof(struct sctp_gap_ack_block) * num_gabs
756 + sizeof(__u32) * num_dup_tsns;
758 /* Create the chunk. */
759 retval = sctp_make_chunk(asoc, SCTP_CID_SACK, 0, len);
760 if (!retval)
761 goto nodata;
763 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
765 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
766 * HEARTBEAT ACK, etc.) to the same destination transport
767 * address from which it received the DATA or control chunk to
768 * which it is replying. This rule should also be followed if
769 * the endpoint is bundling DATA chunks together with the
770 * reply chunk.
772 * However, when acknowledging multiple DATA chunks received
773 * in packets from different source addresses in a single
774 * SACK, the SACK chunk may be transmitted to one of the
775 * destination transport addresses from which the DATA or
776 * control chunks being acknowledged were received.
778 * [BUG: We do not implement the following paragraph.
779 * Perhaps we should remember the last transport we used for a
780 * SACK and avoid that (if possible) if we have seen any
781 * duplicates. --piggy]
783 * When a receiver of a duplicate DATA chunk sends a SACK to a
784 * multi- homed endpoint it MAY be beneficial to vary the
785 * destination address and not use the source address of the
786 * DATA chunk. The reason being that receiving a duplicate
787 * from a multi-homed endpoint might indicate that the return
788 * path (as specified in the source address of the DATA chunk)
789 * for the SACK is broken.
791 * [Send to the address from which we last received a DATA chunk.]
793 retval->transport = asoc->peer.last_data_from;
795 retval->subh.sack_hdr =
796 sctp_addto_chunk(retval, sizeof(sack), &sack);
798 /* Add the gap ack block information. */
799 if (num_gabs)
800 sctp_addto_chunk(retval, sizeof(__u32) * num_gabs,
801 gabs);
803 /* Add the duplicate TSN information. */
804 if (num_dup_tsns)
805 sctp_addto_chunk(retval, sizeof(__u32) * num_dup_tsns,
806 sctp_tsnmap_get_dups(map));
808 nodata:
809 return retval;
812 /* Make a SHUTDOWN chunk. */
813 struct sctp_chunk *sctp_make_shutdown(const struct sctp_association *asoc,
814 const struct sctp_chunk *chunk)
816 struct sctp_chunk *retval;
817 sctp_shutdownhdr_t shut;
818 __u32 ctsn;
820 ctsn = sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map);
821 shut.cum_tsn_ack = htonl(ctsn);
823 retval = sctp_make_chunk(asoc, SCTP_CID_SHUTDOWN, 0,
824 sizeof(sctp_shutdownhdr_t));
825 if (!retval)
826 goto nodata;
828 retval->subh.shutdown_hdr =
829 sctp_addto_chunk(retval, sizeof(shut), &shut);
831 if (chunk)
832 retval->transport = chunk->transport;
833 nodata:
834 return retval;
837 struct sctp_chunk *sctp_make_shutdown_ack(const struct sctp_association *asoc,
838 const struct sctp_chunk *chunk)
840 struct sctp_chunk *retval;
842 retval = sctp_make_chunk(asoc, SCTP_CID_SHUTDOWN_ACK, 0, 0);
844 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
846 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
847 * HEARTBEAT ACK, * etc.) to the same destination transport
848 * address from which it * received the DATA or control chunk
849 * to which it is replying.
851 * [ACK back to where the SHUTDOWN came from.]
853 if (retval && chunk)
854 retval->transport = chunk->transport;
856 return retval;
859 struct sctp_chunk *sctp_make_shutdown_complete(
860 const struct sctp_association *asoc,
861 const struct sctp_chunk *chunk)
863 struct sctp_chunk *retval;
864 __u8 flags = 0;
866 /* Set the T-bit if we have no association (vtag will be
867 * reflected)
869 flags |= asoc ? 0 : SCTP_CHUNK_FLAG_T;
871 retval = sctp_make_chunk(asoc, SCTP_CID_SHUTDOWN_COMPLETE, flags, 0);
873 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
875 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
876 * HEARTBEAT ACK, * etc.) to the same destination transport
877 * address from which it * received the DATA or control chunk
878 * to which it is replying.
880 * [Report SHUTDOWN COMPLETE back to where the SHUTDOWN ACK
881 * came from.]
883 if (retval && chunk)
884 retval->transport = chunk->transport;
886 return retval;
889 /* Create an ABORT. Note that we set the T bit if we have no
890 * association, except when responding to an INIT (sctpimpguide 2.41).
892 struct sctp_chunk *sctp_make_abort(const struct sctp_association *asoc,
893 const struct sctp_chunk *chunk,
894 const size_t hint)
896 struct sctp_chunk *retval;
897 __u8 flags = 0;
899 /* Set the T-bit if we have no association and 'chunk' is not
900 * an INIT (vtag will be reflected).
902 if (!asoc) {
903 if (chunk && chunk->chunk_hdr &&
904 chunk->chunk_hdr->type == SCTP_CID_INIT)
905 flags = 0;
906 else
907 flags = SCTP_CHUNK_FLAG_T;
910 retval = sctp_make_chunk(asoc, SCTP_CID_ABORT, flags, hint);
912 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
914 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
915 * HEARTBEAT ACK, * etc.) to the same destination transport
916 * address from which it * received the DATA or control chunk
917 * to which it is replying.
919 * [ABORT back to where the offender came from.]
921 if (retval && chunk)
922 retval->transport = chunk->transport;
924 return retval;
927 /* Helper to create ABORT with a NO_USER_DATA error. */
928 struct sctp_chunk *sctp_make_abort_no_data(
929 const struct sctp_association *asoc,
930 const struct sctp_chunk *chunk, __u32 tsn)
932 struct sctp_chunk *retval;
933 __be32 payload;
935 retval = sctp_make_abort(asoc, chunk, sizeof(sctp_errhdr_t)
936 + sizeof(tsn));
938 if (!retval)
939 goto no_mem;
941 /* Put the tsn back into network byte order. */
942 payload = htonl(tsn);
943 sctp_init_cause(retval, SCTP_ERROR_NO_DATA, sizeof(payload));
944 sctp_addto_chunk(retval, sizeof(payload), (const void *)&payload);
946 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
948 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
949 * HEARTBEAT ACK, * etc.) to the same destination transport
950 * address from which it * received the DATA or control chunk
951 * to which it is replying.
953 * [ABORT back to where the offender came from.]
955 if (chunk)
956 retval->transport = chunk->transport;
958 no_mem:
959 return retval;
962 /* Helper to create ABORT with a SCTP_ERROR_USER_ABORT error. */
963 struct sctp_chunk *sctp_make_abort_user(const struct sctp_association *asoc,
964 const struct msghdr *msg,
965 size_t paylen)
967 struct sctp_chunk *retval;
968 void *payload = NULL;
969 int err;
971 retval = sctp_make_abort(asoc, NULL, sizeof(sctp_errhdr_t) + paylen);
972 if (!retval)
973 goto err_chunk;
975 if (paylen) {
976 /* Put the msg_iov together into payload. */
977 payload = kmalloc(paylen, GFP_KERNEL);
978 if (!payload)
979 goto err_payload;
981 err = memcpy_fromiovec(payload, msg->msg_iov, paylen);
982 if (err < 0)
983 goto err_copy;
986 sctp_init_cause(retval, SCTP_ERROR_USER_ABORT, paylen);
987 sctp_addto_chunk(retval, paylen, payload);
989 if (paylen)
990 kfree(payload);
992 return retval;
994 err_copy:
995 kfree(payload);
996 err_payload:
997 sctp_chunk_free(retval);
998 retval = NULL;
999 err_chunk:
1000 return retval;
1003 /* Append bytes to the end of a parameter. Will panic if chunk is not big
1004 * enough.
1006 static void *sctp_addto_param(struct sctp_chunk *chunk, int len,
1007 const void *data)
1009 void *target;
1010 int chunklen = ntohs(chunk->chunk_hdr->length);
1012 target = skb_put(chunk->skb, len);
1014 if (data)
1015 memcpy(target, data, len);
1016 else
1017 memset(target, 0, len);
1019 /* Adjust the chunk length field. */
1020 chunk->chunk_hdr->length = htons(chunklen + len);
1021 chunk->chunk_end = skb_tail_pointer(chunk->skb);
1023 return target;
1026 /* Make an ABORT chunk with a PROTOCOL VIOLATION cause code. */
1027 struct sctp_chunk *sctp_make_abort_violation(
1028 const struct sctp_association *asoc,
1029 const struct sctp_chunk *chunk,
1030 const __u8 *payload,
1031 const size_t paylen)
1033 struct sctp_chunk *retval;
1034 struct sctp_paramhdr phdr;
1036 retval = sctp_make_abort(asoc, chunk, sizeof(sctp_errhdr_t) + paylen
1037 + sizeof(sctp_paramhdr_t));
1038 if (!retval)
1039 goto end;
1041 sctp_init_cause(retval, SCTP_ERROR_PROTO_VIOLATION, paylen
1042 + sizeof(sctp_paramhdr_t));
1044 phdr.type = htons(chunk->chunk_hdr->type);
1045 phdr.length = chunk->chunk_hdr->length;
1046 sctp_addto_chunk(retval, paylen, payload);
1047 sctp_addto_param(retval, sizeof(sctp_paramhdr_t), &phdr);
1049 end:
1050 return retval;
1053 struct sctp_chunk *sctp_make_violation_paramlen(
1054 const struct sctp_association *asoc,
1055 const struct sctp_chunk *chunk,
1056 struct sctp_paramhdr *param)
1058 struct sctp_chunk *retval;
1059 static const char error[] = "The following parameter had invalid length:";
1060 size_t payload_len = sizeof(error) + sizeof(sctp_errhdr_t) +
1061 sizeof(sctp_paramhdr_t);
1063 retval = sctp_make_abort(asoc, chunk, payload_len);
1064 if (!retval)
1065 goto nodata;
1067 sctp_init_cause(retval, SCTP_ERROR_PROTO_VIOLATION,
1068 sizeof(error) + sizeof(sctp_paramhdr_t));
1069 sctp_addto_chunk(retval, sizeof(error), error);
1070 sctp_addto_param(retval, sizeof(sctp_paramhdr_t), param);
1072 nodata:
1073 return retval;
1076 /* Make a HEARTBEAT chunk. */
1077 struct sctp_chunk *sctp_make_heartbeat(const struct sctp_association *asoc,
1078 const struct sctp_transport *transport,
1079 const void *payload, const size_t paylen)
1081 struct sctp_chunk *retval = sctp_make_chunk(asoc, SCTP_CID_HEARTBEAT,
1082 0, paylen);
1084 if (!retval)
1085 goto nodata;
1087 /* Cast away the 'const', as this is just telling the chunk
1088 * what transport it belongs to.
1090 retval->transport = (struct sctp_transport *) transport;
1091 retval->subh.hbs_hdr = sctp_addto_chunk(retval, paylen, payload);
1093 nodata:
1094 return retval;
1097 struct sctp_chunk *sctp_make_heartbeat_ack(const struct sctp_association *asoc,
1098 const struct sctp_chunk *chunk,
1099 const void *payload, const size_t paylen)
1101 struct sctp_chunk *retval;
1103 retval = sctp_make_chunk(asoc, SCTP_CID_HEARTBEAT_ACK, 0, paylen);
1104 if (!retval)
1105 goto nodata;
1107 retval->subh.hbs_hdr = sctp_addto_chunk(retval, paylen, payload);
1109 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
1111 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
1112 * HEARTBEAT ACK, * etc.) to the same destination transport
1113 * address from which it * received the DATA or control chunk
1114 * to which it is replying.
1116 * [HBACK back to where the HEARTBEAT came from.]
1118 if (chunk)
1119 retval->transport = chunk->transport;
1121 nodata:
1122 return retval;
1125 /* Create an Operation Error chunk with the specified space reserved.
1126 * This routine can be used for containing multiple causes in the chunk.
1128 static struct sctp_chunk *sctp_make_op_error_space(
1129 const struct sctp_association *asoc,
1130 const struct sctp_chunk *chunk,
1131 size_t size)
1133 struct sctp_chunk *retval;
1135 retval = sctp_make_chunk(asoc, SCTP_CID_ERROR, 0,
1136 sizeof(sctp_errhdr_t) + size);
1137 if (!retval)
1138 goto nodata;
1140 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
1142 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
1143 * HEARTBEAT ACK, etc.) to the same destination transport
1144 * address from which it received the DATA or control chunk
1145 * to which it is replying.
1148 if (chunk)
1149 retval->transport = chunk->transport;
1151 nodata:
1152 return retval;
1155 /* Create an Operation Error chunk of a fixed size,
1156 * specifically, max(asoc->pathmtu, SCTP_DEFAULT_MAXSEGMENT)
1157 * This is a helper function to allocate an error chunk for
1158 * for those invalid parameter codes in which we may not want
1159 * to report all the errors, if the incomming chunk is large
1161 static inline struct sctp_chunk *sctp_make_op_error_fixed(
1162 const struct sctp_association *asoc,
1163 const struct sctp_chunk *chunk)
1165 size_t size = asoc ? asoc->pathmtu : 0;
1167 if (!size)
1168 size = SCTP_DEFAULT_MAXSEGMENT;
1170 return sctp_make_op_error_space(asoc, chunk, size);
1173 /* Create an Operation Error chunk. */
1174 struct sctp_chunk *sctp_make_op_error(const struct sctp_association *asoc,
1175 const struct sctp_chunk *chunk,
1176 __be16 cause_code, const void *payload,
1177 size_t paylen, size_t reserve_tail)
1179 struct sctp_chunk *retval;
1181 retval = sctp_make_op_error_space(asoc, chunk, paylen + reserve_tail);
1182 if (!retval)
1183 goto nodata;
1185 sctp_init_cause(retval, cause_code, paylen + reserve_tail);
1186 sctp_addto_chunk(retval, paylen, payload);
1187 if (reserve_tail)
1188 sctp_addto_param(retval, reserve_tail, NULL);
1190 nodata:
1191 return retval;
1194 struct sctp_chunk *sctp_make_auth(const struct sctp_association *asoc)
1196 struct sctp_chunk *retval;
1197 struct sctp_hmac *hmac_desc;
1198 struct sctp_authhdr auth_hdr;
1199 __u8 *hmac;
1201 /* Get the first hmac that the peer told us to use */
1202 hmac_desc = sctp_auth_asoc_get_hmac(asoc);
1203 if (unlikely(!hmac_desc))
1204 return NULL;
1206 retval = sctp_make_chunk(asoc, SCTP_CID_AUTH, 0,
1207 hmac_desc->hmac_len + sizeof(sctp_authhdr_t));
1208 if (!retval)
1209 return NULL;
1211 auth_hdr.hmac_id = htons(hmac_desc->hmac_id);
1212 auth_hdr.shkey_id = htons(asoc->active_key_id);
1214 retval->subh.auth_hdr = sctp_addto_chunk(retval, sizeof(sctp_authhdr_t),
1215 &auth_hdr);
1217 hmac = skb_put(retval->skb, hmac_desc->hmac_len);
1218 memset(hmac, 0, hmac_desc->hmac_len);
1220 /* Adjust the chunk header to include the empty MAC */
1221 retval->chunk_hdr->length =
1222 htons(ntohs(retval->chunk_hdr->length) + hmac_desc->hmac_len);
1223 retval->chunk_end = skb_tail_pointer(retval->skb);
1225 return retval;
1229 /********************************************************************
1230 * 2nd Level Abstractions
1231 ********************************************************************/
1233 /* Turn an skb into a chunk.
1234 * FIXME: Eventually move the structure directly inside the skb->cb[].
1236 struct sctp_chunk *sctp_chunkify(struct sk_buff *skb,
1237 const struct sctp_association *asoc,
1238 struct sock *sk)
1240 struct sctp_chunk *retval;
1242 retval = kmem_cache_zalloc(sctp_chunk_cachep, GFP_ATOMIC);
1244 if (!retval)
1245 goto nodata;
1247 if (!sk) {
1248 SCTP_DEBUG_PRINTK("chunkifying skb %p w/o an sk\n", skb);
1251 INIT_LIST_HEAD(&retval->list);
1252 retval->skb = skb;
1253 retval->asoc = (struct sctp_association *)asoc;
1254 retval->has_tsn = 0;
1255 retval->has_ssn = 0;
1256 retval->rtt_in_progress = 0;
1257 retval->sent_at = 0;
1258 retval->singleton = 1;
1259 retval->end_of_packet = 0;
1260 retval->ecn_ce_done = 0;
1261 retval->pdiscard = 0;
1263 /* sctpimpguide-05.txt Section 2.8.2
1264 * M1) Each time a new DATA chunk is transmitted
1265 * set the 'TSN.Missing.Report' count for that TSN to 0. The
1266 * 'TSN.Missing.Report' count will be used to determine missing chunks
1267 * and when to fast retransmit.
1269 retval->tsn_missing_report = 0;
1270 retval->tsn_gap_acked = 0;
1271 retval->fast_retransmit = SCTP_CAN_FRTX;
1273 /* If this is a fragmented message, track all fragments
1274 * of the message (for SEND_FAILED).
1276 retval->msg = NULL;
1278 /* Polish the bead hole. */
1279 INIT_LIST_HEAD(&retval->transmitted_list);
1280 INIT_LIST_HEAD(&retval->frag_list);
1281 SCTP_DBG_OBJCNT_INC(chunk);
1282 atomic_set(&retval->refcnt, 1);
1284 nodata:
1285 return retval;
1288 /* Set chunk->source and dest based on the IP header in chunk->skb. */
1289 void sctp_init_addrs(struct sctp_chunk *chunk, union sctp_addr *src,
1290 union sctp_addr *dest)
1292 memcpy(&chunk->source, src, sizeof(union sctp_addr));
1293 memcpy(&chunk->dest, dest, sizeof(union sctp_addr));
1296 /* Extract the source address from a chunk. */
1297 const union sctp_addr *sctp_source(const struct sctp_chunk *chunk)
1299 /* If we have a known transport, use that. */
1300 if (chunk->transport) {
1301 return &chunk->transport->ipaddr;
1302 } else {
1303 /* Otherwise, extract it from the IP header. */
1304 return &chunk->source;
1308 /* Create a new chunk, setting the type and flags headers from the
1309 * arguments, reserving enough space for a 'paylen' byte payload.
1311 SCTP_STATIC
1312 struct sctp_chunk *sctp_make_chunk(const struct sctp_association *asoc,
1313 __u8 type, __u8 flags, int paylen)
1315 struct sctp_chunk *retval;
1316 sctp_chunkhdr_t *chunk_hdr;
1317 struct sk_buff *skb;
1318 struct sock *sk;
1320 /* No need to allocate LL here, as this is only a chunk. */
1321 skb = alloc_skb(WORD_ROUND(sizeof(sctp_chunkhdr_t) + paylen),
1322 GFP_ATOMIC);
1323 if (!skb)
1324 goto nodata;
1326 /* Make room for the chunk header. */
1327 chunk_hdr = (sctp_chunkhdr_t *)skb_put(skb, sizeof(sctp_chunkhdr_t));
1328 chunk_hdr->type = type;
1329 chunk_hdr->flags = flags;
1330 chunk_hdr->length = htons(sizeof(sctp_chunkhdr_t));
1332 sk = asoc ? asoc->base.sk : NULL;
1333 retval = sctp_chunkify(skb, asoc, sk);
1334 if (!retval) {
1335 kfree_skb(skb);
1336 goto nodata;
1339 retval->chunk_hdr = chunk_hdr;
1340 retval->chunk_end = ((__u8 *)chunk_hdr) + sizeof(struct sctp_chunkhdr);
1342 /* Determine if the chunk needs to be authenticated */
1343 if (sctp_auth_send_cid(type, asoc))
1344 retval->auth = 1;
1346 /* Set the skb to the belonging sock for accounting. */
1347 skb->sk = sk;
1349 return retval;
1350 nodata:
1351 return NULL;
1355 /* Release the memory occupied by a chunk. */
1356 static void sctp_chunk_destroy(struct sctp_chunk *chunk)
1358 BUG_ON(!list_empty(&chunk->list));
1359 list_del_init(&chunk->transmitted_list);
1361 /* Free the chunk skb data and the SCTP_chunk stub itself. */
1362 dev_kfree_skb(chunk->skb);
1364 SCTP_DBG_OBJCNT_DEC(chunk);
1365 kmem_cache_free(sctp_chunk_cachep, chunk);
1368 /* Possibly, free the chunk. */
1369 void sctp_chunk_free(struct sctp_chunk *chunk)
1371 /* Release our reference on the message tracker. */
1372 if (chunk->msg)
1373 sctp_datamsg_put(chunk->msg);
1375 sctp_chunk_put(chunk);
1378 /* Grab a reference to the chunk. */
1379 void sctp_chunk_hold(struct sctp_chunk *ch)
1381 atomic_inc(&ch->refcnt);
1384 /* Release a reference to the chunk. */
1385 void sctp_chunk_put(struct sctp_chunk *ch)
1387 if (atomic_dec_and_test(&ch->refcnt))
1388 sctp_chunk_destroy(ch);
1391 /* Append bytes to the end of a chunk. Will panic if chunk is not big
1392 * enough.
1394 void *sctp_addto_chunk(struct sctp_chunk *chunk, int len, const void *data)
1396 void *target;
1397 void *padding;
1398 int chunklen = ntohs(chunk->chunk_hdr->length);
1399 int padlen = WORD_ROUND(chunklen) - chunklen;
1401 padding = skb_put(chunk->skb, padlen);
1402 target = skb_put(chunk->skb, len);
1404 memset(padding, 0, padlen);
1405 memcpy(target, data, len);
1407 /* Adjust the chunk length field. */
1408 chunk->chunk_hdr->length = htons(chunklen + padlen + len);
1409 chunk->chunk_end = skb_tail_pointer(chunk->skb);
1411 return target;
1414 /* Append bytes to the end of a chunk. Returns NULL if there isn't sufficient
1415 * space in the chunk
1417 void *sctp_addto_chunk_fixed(struct sctp_chunk *chunk,
1418 int len, const void *data)
1420 if (skb_tailroom(chunk->skb) >= len)
1421 return sctp_addto_chunk(chunk, len, data);
1422 else
1423 return NULL;
1426 /* Append bytes from user space to the end of a chunk. Will panic if
1427 * chunk is not big enough.
1428 * Returns a kernel err value.
1430 int sctp_user_addto_chunk(struct sctp_chunk *chunk, int off, int len,
1431 struct iovec *data)
1433 __u8 *target;
1434 int err = 0;
1436 /* Make room in chunk for data. */
1437 target = skb_put(chunk->skb, len);
1439 /* Copy data (whole iovec) into chunk */
1440 if ((err = memcpy_fromiovecend(target, data, off, len)))
1441 goto out;
1443 /* Adjust the chunk length field. */
1444 chunk->chunk_hdr->length =
1445 htons(ntohs(chunk->chunk_hdr->length) + len);
1446 chunk->chunk_end = skb_tail_pointer(chunk->skb);
1448 out:
1449 return err;
1452 /* Helper function to assign a TSN if needed. This assumes that both
1453 * the data_hdr and association have already been assigned.
1455 void sctp_chunk_assign_ssn(struct sctp_chunk *chunk)
1457 struct sctp_datamsg *msg;
1458 struct sctp_chunk *lchunk;
1459 struct sctp_stream *stream;
1460 __u16 ssn;
1461 __u16 sid;
1463 if (chunk->has_ssn)
1464 return;
1466 /* All fragments will be on the same stream */
1467 sid = ntohs(chunk->subh.data_hdr->stream);
1468 stream = &chunk->asoc->ssnmap->out;
1470 /* Now assign the sequence number to the entire message.
1471 * All fragments must have the same stream sequence number.
1473 msg = chunk->msg;
1474 list_for_each_entry(lchunk, &msg->chunks, frag_list) {
1475 if (lchunk->chunk_hdr->flags & SCTP_DATA_UNORDERED) {
1476 ssn = 0;
1477 } else {
1478 if (lchunk->chunk_hdr->flags & SCTP_DATA_LAST_FRAG)
1479 ssn = sctp_ssn_next(stream, sid);
1480 else
1481 ssn = sctp_ssn_peek(stream, sid);
1484 lchunk->subh.data_hdr->ssn = htons(ssn);
1485 lchunk->has_ssn = 1;
1489 /* Helper function to assign a TSN if needed. This assumes that both
1490 * the data_hdr and association have already been assigned.
1492 void sctp_chunk_assign_tsn(struct sctp_chunk *chunk)
1494 if (!chunk->has_tsn) {
1495 /* This is the last possible instant to
1496 * assign a TSN.
1498 chunk->subh.data_hdr->tsn =
1499 htonl(sctp_association_get_next_tsn(chunk->asoc));
1500 chunk->has_tsn = 1;
1504 /* Create a CLOSED association to use with an incoming packet. */
1505 struct sctp_association *sctp_make_temp_asoc(const struct sctp_endpoint *ep,
1506 struct sctp_chunk *chunk,
1507 gfp_t gfp)
1509 struct sctp_association *asoc;
1510 struct sk_buff *skb;
1511 sctp_scope_t scope;
1512 struct sctp_af *af;
1514 /* Create the bare association. */
1515 scope = sctp_scope(sctp_source(chunk));
1516 asoc = sctp_association_new(ep, ep->base.sk, scope, gfp);
1517 if (!asoc)
1518 goto nodata;
1519 asoc->temp = 1;
1520 skb = chunk->skb;
1521 /* Create an entry for the source address of the packet. */
1522 af = sctp_get_af_specific(ipver2af(ip_hdr(skb)->version));
1523 if (unlikely(!af))
1524 goto fail;
1525 af->from_skb(&asoc->c.peer_addr, skb, 1);
1526 nodata:
1527 return asoc;
1529 fail:
1530 sctp_association_free(asoc);
1531 return NULL;
1534 /* Build a cookie representing asoc.
1535 * This INCLUDES the param header needed to put the cookie in the INIT ACK.
1537 static sctp_cookie_param_t *sctp_pack_cookie(const struct sctp_endpoint *ep,
1538 const struct sctp_association *asoc,
1539 const struct sctp_chunk *init_chunk,
1540 int *cookie_len,
1541 const __u8 *raw_addrs, int addrs_len)
1543 sctp_cookie_param_t *retval;
1544 struct sctp_signed_cookie *cookie;
1545 struct scatterlist sg;
1546 int headersize, bodysize;
1547 unsigned int keylen;
1548 char *key;
1550 /* Header size is static data prior to the actual cookie, including
1551 * any padding.
1553 headersize = sizeof(sctp_paramhdr_t) +
1554 (sizeof(struct sctp_signed_cookie) -
1555 sizeof(struct sctp_cookie));
1556 bodysize = sizeof(struct sctp_cookie)
1557 + ntohs(init_chunk->chunk_hdr->length) + addrs_len;
1559 /* Pad out the cookie to a multiple to make the signature
1560 * functions simpler to write.
1562 if (bodysize % SCTP_COOKIE_MULTIPLE)
1563 bodysize += SCTP_COOKIE_MULTIPLE
1564 - (bodysize % SCTP_COOKIE_MULTIPLE);
1565 *cookie_len = headersize + bodysize;
1567 /* Clear this memory since we are sending this data structure
1568 * out on the network.
1570 retval = kzalloc(*cookie_len, GFP_ATOMIC);
1571 if (!retval)
1572 goto nodata;
1574 cookie = (struct sctp_signed_cookie *) retval->body;
1576 /* Set up the parameter header. */
1577 retval->p.type = SCTP_PARAM_STATE_COOKIE;
1578 retval->p.length = htons(*cookie_len);
1580 /* Copy the cookie part of the association itself. */
1581 cookie->c = asoc->c;
1582 /* Save the raw address list length in the cookie. */
1583 cookie->c.raw_addr_list_len = addrs_len;
1585 /* Remember PR-SCTP capability. */
1586 cookie->c.prsctp_capable = asoc->peer.prsctp_capable;
1588 /* Save adaptation indication in the cookie. */
1589 cookie->c.adaptation_ind = asoc->peer.adaptation_ind;
1591 /* Set an expiration time for the cookie. */
1592 do_gettimeofday(&cookie->c.expiration);
1593 TIMEVAL_ADD(asoc->cookie_life, cookie->c.expiration);
1595 /* Copy the peer's init packet. */
1596 memcpy(&cookie->c.peer_init[0], init_chunk->chunk_hdr,
1597 ntohs(init_chunk->chunk_hdr->length));
1599 /* Copy the raw local address list of the association. */
1600 memcpy((__u8 *)&cookie->c.peer_init[0] +
1601 ntohs(init_chunk->chunk_hdr->length), raw_addrs, addrs_len);
1603 if (sctp_sk(ep->base.sk)->hmac) {
1604 struct hash_desc desc;
1606 /* Sign the message. */
1607 sg_init_one(&sg, &cookie->c, bodysize);
1608 keylen = SCTP_SECRET_SIZE;
1609 key = (char *)ep->secret_key[ep->current_key];
1610 desc.tfm = sctp_sk(ep->base.sk)->hmac;
1611 desc.flags = 0;
1613 if (crypto_hash_setkey(desc.tfm, key, keylen) ||
1614 crypto_hash_digest(&desc, &sg, bodysize, cookie->signature))
1615 goto free_cookie;
1618 return retval;
1620 free_cookie:
1621 kfree(retval);
1622 nodata:
1623 *cookie_len = 0;
1624 return NULL;
1627 /* Unpack the cookie from COOKIE ECHO chunk, recreating the association. */
1628 struct sctp_association *sctp_unpack_cookie(
1629 const struct sctp_endpoint *ep,
1630 const struct sctp_association *asoc,
1631 struct sctp_chunk *chunk, gfp_t gfp,
1632 int *error, struct sctp_chunk **errp)
1634 struct sctp_association *retval = NULL;
1635 struct sctp_signed_cookie *cookie;
1636 struct sctp_cookie *bear_cookie;
1637 int headersize, bodysize, fixed_size;
1638 __u8 *digest = ep->digest;
1639 struct scatterlist sg;
1640 unsigned int keylen, len;
1641 char *key;
1642 sctp_scope_t scope;
1643 struct sk_buff *skb = chunk->skb;
1644 struct timeval tv;
1645 struct hash_desc desc;
1647 /* Header size is static data prior to the actual cookie, including
1648 * any padding.
1650 headersize = sizeof(sctp_chunkhdr_t) +
1651 (sizeof(struct sctp_signed_cookie) -
1652 sizeof(struct sctp_cookie));
1653 bodysize = ntohs(chunk->chunk_hdr->length) - headersize;
1654 fixed_size = headersize + sizeof(struct sctp_cookie);
1656 /* Verify that the chunk looks like it even has a cookie.
1657 * There must be enough room for our cookie and our peer's
1658 * INIT chunk.
1660 len = ntohs(chunk->chunk_hdr->length);
1661 if (len < fixed_size + sizeof(struct sctp_chunkhdr))
1662 goto malformed;
1664 /* Verify that the cookie has been padded out. */
1665 if (bodysize % SCTP_COOKIE_MULTIPLE)
1666 goto malformed;
1668 /* Process the cookie. */
1669 cookie = chunk->subh.cookie_hdr;
1670 bear_cookie = &cookie->c;
1672 if (!sctp_sk(ep->base.sk)->hmac)
1673 goto no_hmac;
1675 /* Check the signature. */
1676 keylen = SCTP_SECRET_SIZE;
1677 sg_init_one(&sg, bear_cookie, bodysize);
1678 key = (char *)ep->secret_key[ep->current_key];
1679 desc.tfm = sctp_sk(ep->base.sk)->hmac;
1680 desc.flags = 0;
1682 memset(digest, 0x00, SCTP_SIGNATURE_SIZE);
1683 if (crypto_hash_setkey(desc.tfm, key, keylen) ||
1684 crypto_hash_digest(&desc, &sg, bodysize, digest)) {
1685 *error = -SCTP_IERROR_NOMEM;
1686 goto fail;
1689 if (memcmp(digest, cookie->signature, SCTP_SIGNATURE_SIZE)) {
1690 /* Try the previous key. */
1691 key = (char *)ep->secret_key[ep->last_key];
1692 memset(digest, 0x00, SCTP_SIGNATURE_SIZE);
1693 if (crypto_hash_setkey(desc.tfm, key, keylen) ||
1694 crypto_hash_digest(&desc, &sg, bodysize, digest)) {
1695 *error = -SCTP_IERROR_NOMEM;
1696 goto fail;
1699 if (memcmp(digest, cookie->signature, SCTP_SIGNATURE_SIZE)) {
1700 /* Yikes! Still bad signature! */
1701 *error = -SCTP_IERROR_BAD_SIG;
1702 goto fail;
1706 no_hmac:
1707 /* IG Section 2.35.2:
1708 * 3) Compare the port numbers and the verification tag contained
1709 * within the COOKIE ECHO chunk to the actual port numbers and the
1710 * verification tag within the SCTP common header of the received
1711 * packet. If these values do not match the packet MUST be silently
1712 * discarded,
1714 if (ntohl(chunk->sctp_hdr->vtag) != bear_cookie->my_vtag) {
1715 *error = -SCTP_IERROR_BAD_TAG;
1716 goto fail;
1719 if (chunk->sctp_hdr->source != bear_cookie->peer_addr.v4.sin_port ||
1720 ntohs(chunk->sctp_hdr->dest) != bear_cookie->my_port) {
1721 *error = -SCTP_IERROR_BAD_PORTS;
1722 goto fail;
1725 /* Check to see if the cookie is stale. If there is already
1726 * an association, there is no need to check cookie's expiration
1727 * for init collision case of lost COOKIE ACK.
1728 * If skb has been timestamped, then use the stamp, otherwise
1729 * use current time. This introduces a small possibility that
1730 * that a cookie may be considered expired, but his would only slow
1731 * down the new association establishment instead of every packet.
1733 if (sock_flag(ep->base.sk, SOCK_TIMESTAMP))
1734 skb_get_timestamp(skb, &tv);
1735 else
1736 do_gettimeofday(&tv);
1738 if (!asoc && tv_lt(bear_cookie->expiration, tv)) {
1740 * Section 3.3.10.3 Stale Cookie Error (3)
1742 * Cause of error
1743 * ---------------
1744 * Stale Cookie Error: Indicates the receipt of a valid State
1745 * Cookie that has expired.
1747 len = ntohs(chunk->chunk_hdr->length);
1748 *errp = sctp_make_op_error_space(asoc, chunk, len);
1749 if (*errp) {
1750 suseconds_t usecs = (tv.tv_sec -
1751 bear_cookie->expiration.tv_sec) * 1000000L +
1752 tv.tv_usec - bear_cookie->expiration.tv_usec;
1753 __be32 n = htonl(usecs);
1755 sctp_init_cause(*errp, SCTP_ERROR_STALE_COOKIE,
1756 sizeof(n));
1757 sctp_addto_chunk(*errp, sizeof(n), &n);
1758 *error = -SCTP_IERROR_STALE_COOKIE;
1759 } else
1760 *error = -SCTP_IERROR_NOMEM;
1762 goto fail;
1765 /* Make a new base association. */
1766 scope = sctp_scope(sctp_source(chunk));
1767 retval = sctp_association_new(ep, ep->base.sk, scope, gfp);
1768 if (!retval) {
1769 *error = -SCTP_IERROR_NOMEM;
1770 goto fail;
1773 /* Set up our peer's port number. */
1774 retval->peer.port = ntohs(chunk->sctp_hdr->source);
1776 /* Populate the association from the cookie. */
1777 memcpy(&retval->c, bear_cookie, sizeof(*bear_cookie));
1779 if (sctp_assoc_set_bind_addr_from_cookie(retval, bear_cookie,
1780 GFP_ATOMIC) < 0) {
1781 *error = -SCTP_IERROR_NOMEM;
1782 goto fail;
1785 /* Also, add the destination address. */
1786 if (list_empty(&retval->base.bind_addr.address_list)) {
1787 sctp_add_bind_addr(&retval->base.bind_addr, &chunk->dest,
1788 SCTP_ADDR_SRC, GFP_ATOMIC);
1791 retval->next_tsn = retval->c.initial_tsn;
1792 retval->ctsn_ack_point = retval->next_tsn - 1;
1793 retval->addip_serial = retval->c.initial_tsn;
1794 retval->adv_peer_ack_point = retval->ctsn_ack_point;
1795 retval->peer.prsctp_capable = retval->c.prsctp_capable;
1796 retval->peer.adaptation_ind = retval->c.adaptation_ind;
1798 /* The INIT stuff will be done by the side effects. */
1799 return retval;
1801 fail:
1802 if (retval)
1803 sctp_association_free(retval);
1805 return NULL;
1807 malformed:
1808 /* Yikes! The packet is either corrupt or deliberately
1809 * malformed.
1811 *error = -SCTP_IERROR_MALFORMED;
1812 goto fail;
1815 /********************************************************************
1816 * 3rd Level Abstractions
1817 ********************************************************************/
1819 struct __sctp_missing {
1820 __be32 num_missing;
1821 __be16 type;
1822 } __packed;
1825 * Report a missing mandatory parameter.
1827 static int sctp_process_missing_param(const struct sctp_association *asoc,
1828 sctp_param_t paramtype,
1829 struct sctp_chunk *chunk,
1830 struct sctp_chunk **errp)
1832 struct __sctp_missing report;
1833 __u16 len;
1835 len = WORD_ROUND(sizeof(report));
1837 /* Make an ERROR chunk, preparing enough room for
1838 * returning multiple unknown parameters.
1840 if (!*errp)
1841 *errp = sctp_make_op_error_space(asoc, chunk, len);
1843 if (*errp) {
1844 report.num_missing = htonl(1);
1845 report.type = paramtype;
1846 sctp_init_cause(*errp, SCTP_ERROR_MISS_PARAM,
1847 sizeof(report));
1848 sctp_addto_chunk(*errp, sizeof(report), &report);
1851 /* Stop processing this chunk. */
1852 return 0;
1855 /* Report an Invalid Mandatory Parameter. */
1856 static int sctp_process_inv_mandatory(const struct sctp_association *asoc,
1857 struct sctp_chunk *chunk,
1858 struct sctp_chunk **errp)
1860 /* Invalid Mandatory Parameter Error has no payload. */
1862 if (!*errp)
1863 *errp = sctp_make_op_error_space(asoc, chunk, 0);
1865 if (*errp)
1866 sctp_init_cause(*errp, SCTP_ERROR_INV_PARAM, 0);
1868 /* Stop processing this chunk. */
1869 return 0;
1872 static int sctp_process_inv_paramlength(const struct sctp_association *asoc,
1873 struct sctp_paramhdr *param,
1874 const struct sctp_chunk *chunk,
1875 struct sctp_chunk **errp)
1877 /* This is a fatal error. Any accumulated non-fatal errors are
1878 * not reported.
1880 if (*errp)
1881 sctp_chunk_free(*errp);
1883 /* Create an error chunk and fill it in with our payload. */
1884 *errp = sctp_make_violation_paramlen(asoc, chunk, param);
1886 return 0;
1890 /* Do not attempt to handle the HOST_NAME parm. However, do
1891 * send back an indicator to the peer.
1893 static int sctp_process_hn_param(const struct sctp_association *asoc,
1894 union sctp_params param,
1895 struct sctp_chunk *chunk,
1896 struct sctp_chunk **errp)
1898 __u16 len = ntohs(param.p->length);
1900 /* Processing of the HOST_NAME parameter will generate an
1901 * ABORT. If we've accumulated any non-fatal errors, they
1902 * would be unrecognized parameters and we should not include
1903 * them in the ABORT.
1905 if (*errp)
1906 sctp_chunk_free(*errp);
1908 *errp = sctp_make_op_error_space(asoc, chunk, len);
1910 if (*errp) {
1911 sctp_init_cause(*errp, SCTP_ERROR_DNS_FAILED, len);
1912 sctp_addto_chunk(*errp, len, param.v);
1915 /* Stop processing this chunk. */
1916 return 0;
1919 static int sctp_verify_ext_param(union sctp_params param)
1921 __u16 num_ext = ntohs(param.p->length) - sizeof(sctp_paramhdr_t);
1922 int have_auth = 0;
1923 int have_asconf = 0;
1924 int i;
1926 for (i = 0; i < num_ext; i++) {
1927 switch (param.ext->chunks[i]) {
1928 case SCTP_CID_AUTH:
1929 have_auth = 1;
1930 break;
1931 case SCTP_CID_ASCONF:
1932 case SCTP_CID_ASCONF_ACK:
1933 have_asconf = 1;
1934 break;
1938 /* ADD-IP Security: The draft requires us to ABORT or ignore the
1939 * INIT/INIT-ACK if ADD-IP is listed, but AUTH is not. Do this
1940 * only if ADD-IP is turned on and we are not backward-compatible
1941 * mode.
1943 if (sctp_addip_noauth)
1944 return 1;
1946 if (sctp_addip_enable && !have_auth && have_asconf)
1947 return 0;
1949 return 1;
1952 static void sctp_process_ext_param(struct sctp_association *asoc,
1953 union sctp_params param)
1955 __u16 num_ext = ntohs(param.p->length) - sizeof(sctp_paramhdr_t);
1956 int i;
1958 for (i = 0; i < num_ext; i++) {
1959 switch (param.ext->chunks[i]) {
1960 case SCTP_CID_FWD_TSN:
1961 if (sctp_prsctp_enable &&
1962 !asoc->peer.prsctp_capable)
1963 asoc->peer.prsctp_capable = 1;
1964 break;
1965 case SCTP_CID_AUTH:
1966 /* if the peer reports AUTH, assume that he
1967 * supports AUTH.
1969 if (sctp_auth_enable)
1970 asoc->peer.auth_capable = 1;
1971 break;
1972 case SCTP_CID_ASCONF:
1973 case SCTP_CID_ASCONF_ACK:
1974 if (sctp_addip_enable)
1975 asoc->peer.asconf_capable = 1;
1976 break;
1977 default:
1978 break;
1983 /* RFC 3.2.1 & the Implementers Guide 2.2.
1985 * The Parameter Types are encoded such that the
1986 * highest-order two bits specify the action that must be
1987 * taken if the processing endpoint does not recognize the
1988 * Parameter Type.
1990 * 00 - Stop processing this parameter; do not process any further
1991 * parameters within this chunk
1993 * 01 - Stop processing this parameter, do not process any further
1994 * parameters within this chunk, and report the unrecognized
1995 * parameter in an 'Unrecognized Parameter' ERROR chunk.
1997 * 10 - Skip this parameter and continue processing.
1999 * 11 - Skip this parameter and continue processing but
2000 * report the unrecognized parameter in an
2001 * 'Unrecognized Parameter' ERROR chunk.
2003 * Return value:
2004 * SCTP_IERROR_NO_ERROR - continue with the chunk
2005 * SCTP_IERROR_ERROR - stop and report an error.
2006 * SCTP_IERROR_NOMEME - out of memory.
2008 static sctp_ierror_t sctp_process_unk_param(const struct sctp_association *asoc,
2009 union sctp_params param,
2010 struct sctp_chunk *chunk,
2011 struct sctp_chunk **errp)
2013 int retval = SCTP_IERROR_NO_ERROR;
2015 switch (param.p->type & SCTP_PARAM_ACTION_MASK) {
2016 case SCTP_PARAM_ACTION_DISCARD:
2017 retval = SCTP_IERROR_ERROR;
2018 break;
2019 case SCTP_PARAM_ACTION_SKIP:
2020 break;
2021 case SCTP_PARAM_ACTION_DISCARD_ERR:
2022 retval = SCTP_IERROR_ERROR;
2023 /* Fall through */
2024 case SCTP_PARAM_ACTION_SKIP_ERR:
2025 /* Make an ERROR chunk, preparing enough room for
2026 * returning multiple unknown parameters.
2028 if (NULL == *errp)
2029 *errp = sctp_make_op_error_fixed(asoc, chunk);
2031 if (*errp) {
2032 sctp_init_cause_fixed(*errp, SCTP_ERROR_UNKNOWN_PARAM,
2033 WORD_ROUND(ntohs(param.p->length)));
2034 sctp_addto_chunk_fixed(*errp,
2035 WORD_ROUND(ntohs(param.p->length)),
2036 param.v);
2037 } else {
2038 /* If there is no memory for generating the ERROR
2039 * report as specified, an ABORT will be triggered
2040 * to the peer and the association won't be
2041 * established.
2043 retval = SCTP_IERROR_NOMEM;
2045 break;
2046 default:
2047 break;
2050 return retval;
2053 /* Verify variable length parameters
2054 * Return values:
2055 * SCTP_IERROR_ABORT - trigger an ABORT
2056 * SCTP_IERROR_NOMEM - out of memory (abort)
2057 * SCTP_IERROR_ERROR - stop processing, trigger an ERROR
2058 * SCTP_IERROR_NO_ERROR - continue with the chunk
2060 static sctp_ierror_t sctp_verify_param(const struct sctp_association *asoc,
2061 union sctp_params param,
2062 sctp_cid_t cid,
2063 struct sctp_chunk *chunk,
2064 struct sctp_chunk **err_chunk)
2066 struct sctp_hmac_algo_param *hmacs;
2067 int retval = SCTP_IERROR_NO_ERROR;
2068 __u16 n_elt, id = 0;
2069 int i;
2071 /* FIXME - This routine is not looking at each parameter per the
2072 * chunk type, i.e., unrecognized parameters should be further
2073 * identified based on the chunk id.
2076 switch (param.p->type) {
2077 case SCTP_PARAM_IPV4_ADDRESS:
2078 case SCTP_PARAM_IPV6_ADDRESS:
2079 case SCTP_PARAM_COOKIE_PRESERVATIVE:
2080 case SCTP_PARAM_SUPPORTED_ADDRESS_TYPES:
2081 case SCTP_PARAM_STATE_COOKIE:
2082 case SCTP_PARAM_HEARTBEAT_INFO:
2083 case SCTP_PARAM_UNRECOGNIZED_PARAMETERS:
2084 case SCTP_PARAM_ECN_CAPABLE:
2085 case SCTP_PARAM_ADAPTATION_LAYER_IND:
2086 break;
2088 case SCTP_PARAM_SUPPORTED_EXT:
2089 if (!sctp_verify_ext_param(param))
2090 return SCTP_IERROR_ABORT;
2091 break;
2093 case SCTP_PARAM_SET_PRIMARY:
2094 if (sctp_addip_enable)
2095 break;
2096 goto fallthrough;
2098 case SCTP_PARAM_HOST_NAME_ADDRESS:
2099 /* Tell the peer, we won't support this param. */
2100 sctp_process_hn_param(asoc, param, chunk, err_chunk);
2101 retval = SCTP_IERROR_ABORT;
2102 break;
2104 case SCTP_PARAM_FWD_TSN_SUPPORT:
2105 if (sctp_prsctp_enable)
2106 break;
2107 goto fallthrough;
2109 case SCTP_PARAM_RANDOM:
2110 if (!sctp_auth_enable)
2111 goto fallthrough;
2113 /* SCTP-AUTH: Secion 6.1
2114 * If the random number is not 32 byte long the association
2115 * MUST be aborted. The ABORT chunk SHOULD contain the error
2116 * cause 'Protocol Violation'.
2118 if (SCTP_AUTH_RANDOM_LENGTH !=
2119 ntohs(param.p->length) - sizeof(sctp_paramhdr_t)) {
2120 sctp_process_inv_paramlength(asoc, param.p,
2121 chunk, err_chunk);
2122 retval = SCTP_IERROR_ABORT;
2124 break;
2126 case SCTP_PARAM_CHUNKS:
2127 if (!sctp_auth_enable)
2128 goto fallthrough;
2130 /* SCTP-AUTH: Section 3.2
2131 * The CHUNKS parameter MUST be included once in the INIT or
2132 * INIT-ACK chunk if the sender wants to receive authenticated
2133 * chunks. Its maximum length is 260 bytes.
2135 if (260 < ntohs(param.p->length)) {
2136 sctp_process_inv_paramlength(asoc, param.p,
2137 chunk, err_chunk);
2138 retval = SCTP_IERROR_ABORT;
2140 break;
2142 case SCTP_PARAM_HMAC_ALGO:
2143 if (!sctp_auth_enable)
2144 goto fallthrough;
2146 hmacs = (struct sctp_hmac_algo_param *)param.p;
2147 n_elt = (ntohs(param.p->length) - sizeof(sctp_paramhdr_t)) >> 1;
2149 /* SCTP-AUTH: Section 6.1
2150 * The HMAC algorithm based on SHA-1 MUST be supported and
2151 * included in the HMAC-ALGO parameter.
2153 for (i = 0; i < n_elt; i++) {
2154 id = ntohs(hmacs->hmac_ids[i]);
2156 if (id == SCTP_AUTH_HMAC_ID_SHA1)
2157 break;
2160 if (id != SCTP_AUTH_HMAC_ID_SHA1) {
2161 sctp_process_inv_paramlength(asoc, param.p, chunk,
2162 err_chunk);
2163 retval = SCTP_IERROR_ABORT;
2165 break;
2166 fallthrough:
2167 default:
2168 SCTP_DEBUG_PRINTK("Unrecognized param: %d for chunk %d.\n",
2169 ntohs(param.p->type), cid);
2170 retval = sctp_process_unk_param(asoc, param, chunk, err_chunk);
2171 break;
2173 return retval;
2176 /* Verify the INIT packet before we process it. */
2177 int sctp_verify_init(const struct sctp_association *asoc,
2178 sctp_cid_t cid,
2179 sctp_init_chunk_t *peer_init,
2180 struct sctp_chunk *chunk,
2181 struct sctp_chunk **errp)
2183 union sctp_params param;
2184 int has_cookie = 0;
2185 int result;
2187 /* Verify stream values are non-zero. */
2188 if ((0 == peer_init->init_hdr.num_outbound_streams) ||
2189 (0 == peer_init->init_hdr.num_inbound_streams) ||
2190 (0 == peer_init->init_hdr.init_tag) ||
2191 (SCTP_DEFAULT_MINWINDOW > ntohl(peer_init->init_hdr.a_rwnd))) {
2193 return sctp_process_inv_mandatory(asoc, chunk, errp);
2196 /* Check for missing mandatory parameters. */
2197 sctp_walk_params(param, peer_init, init_hdr.params) {
2199 if (SCTP_PARAM_STATE_COOKIE == param.p->type)
2200 has_cookie = 1;
2202 } /* for (loop through all parameters) */
2204 /* There is a possibility that a parameter length was bad and
2205 * in that case we would have stoped walking the parameters.
2206 * The current param.p would point at the bad one.
2207 * Current consensus on the mailing list is to generate a PROTOCOL
2208 * VIOLATION error. We build the ERROR chunk here and let the normal
2209 * error handling code build and send the packet.
2211 if (param.v != (void*)chunk->chunk_end)
2212 return sctp_process_inv_paramlength(asoc, param.p, chunk, errp);
2214 /* The only missing mandatory param possible today is
2215 * the state cookie for an INIT-ACK chunk.
2217 if ((SCTP_CID_INIT_ACK == cid) && !has_cookie)
2218 return sctp_process_missing_param(asoc, SCTP_PARAM_STATE_COOKIE,
2219 chunk, errp);
2221 /* Verify all the variable length parameters */
2222 sctp_walk_params(param, peer_init, init_hdr.params) {
2224 result = sctp_verify_param(asoc, param, cid, chunk, errp);
2225 switch (result) {
2226 case SCTP_IERROR_ABORT:
2227 case SCTP_IERROR_NOMEM:
2228 return 0;
2229 case SCTP_IERROR_ERROR:
2230 return 1;
2231 case SCTP_IERROR_NO_ERROR:
2232 default:
2233 break;
2236 } /* for (loop through all parameters) */
2238 return 1;
2241 /* Unpack the parameters in an INIT packet into an association.
2242 * Returns 0 on failure, else success.
2243 * FIXME: This is an association method.
2245 int sctp_process_init(struct sctp_association *asoc, sctp_cid_t cid,
2246 const union sctp_addr *peer_addr,
2247 sctp_init_chunk_t *peer_init, gfp_t gfp)
2249 union sctp_params param;
2250 struct sctp_transport *transport;
2251 struct list_head *pos, *temp;
2252 char *cookie;
2254 /* We must include the address that the INIT packet came from.
2255 * This is the only address that matters for an INIT packet.
2256 * When processing a COOKIE ECHO, we retrieve the from address
2257 * of the INIT from the cookie.
2260 /* This implementation defaults to making the first transport
2261 * added as the primary transport. The source address seems to
2262 * be a a better choice than any of the embedded addresses.
2264 if (peer_addr) {
2265 if(!sctp_assoc_add_peer(asoc, peer_addr, gfp, SCTP_ACTIVE))
2266 goto nomem;
2269 /* Process the initialization parameters. */
2270 sctp_walk_params(param, peer_init, init_hdr.params) {
2272 if (!sctp_process_param(asoc, param, peer_addr, gfp))
2273 goto clean_up;
2276 /* AUTH: After processing the parameters, make sure that we
2277 * have all the required info to potentially do authentications.
2279 if (asoc->peer.auth_capable && (!asoc->peer.peer_random ||
2280 !asoc->peer.peer_hmacs))
2281 asoc->peer.auth_capable = 0;
2283 /* In a non-backward compatible mode, if the peer claims
2284 * support for ADD-IP but not AUTH, the ADD-IP spec states
2285 * that we MUST ABORT the association. Section 6. The section
2286 * also give us an option to silently ignore the packet, which
2287 * is what we'll do here.
2289 if (!sctp_addip_noauth &&
2290 (asoc->peer.asconf_capable && !asoc->peer.auth_capable)) {
2291 asoc->peer.addip_disabled_mask |= (SCTP_PARAM_ADD_IP |
2292 SCTP_PARAM_DEL_IP |
2293 SCTP_PARAM_SET_PRIMARY);
2294 asoc->peer.asconf_capable = 0;
2295 goto clean_up;
2298 /* Walk list of transports, removing transports in the UNKNOWN state. */
2299 list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
2300 transport = list_entry(pos, struct sctp_transport, transports);
2301 if (transport->state == SCTP_UNKNOWN) {
2302 sctp_assoc_rm_peer(asoc, transport);
2306 /* The fixed INIT headers are always in network byte
2307 * order.
2309 asoc->peer.i.init_tag =
2310 ntohl(peer_init->init_hdr.init_tag);
2311 asoc->peer.i.a_rwnd =
2312 ntohl(peer_init->init_hdr.a_rwnd);
2313 asoc->peer.i.num_outbound_streams =
2314 ntohs(peer_init->init_hdr.num_outbound_streams);
2315 asoc->peer.i.num_inbound_streams =
2316 ntohs(peer_init->init_hdr.num_inbound_streams);
2317 asoc->peer.i.initial_tsn =
2318 ntohl(peer_init->init_hdr.initial_tsn);
2320 /* Apply the upper bounds for output streams based on peer's
2321 * number of inbound streams.
2323 if (asoc->c.sinit_num_ostreams >
2324 ntohs(peer_init->init_hdr.num_inbound_streams)) {
2325 asoc->c.sinit_num_ostreams =
2326 ntohs(peer_init->init_hdr.num_inbound_streams);
2329 if (asoc->c.sinit_max_instreams >
2330 ntohs(peer_init->init_hdr.num_outbound_streams)) {
2331 asoc->c.sinit_max_instreams =
2332 ntohs(peer_init->init_hdr.num_outbound_streams);
2335 /* Copy Initiation tag from INIT to VT_peer in cookie. */
2336 asoc->c.peer_vtag = asoc->peer.i.init_tag;
2338 /* Peer Rwnd : Current calculated value of the peer's rwnd. */
2339 asoc->peer.rwnd = asoc->peer.i.a_rwnd;
2341 /* Copy cookie in case we need to resend COOKIE-ECHO. */
2342 cookie = asoc->peer.cookie;
2343 if (cookie) {
2344 asoc->peer.cookie = kmemdup(cookie, asoc->peer.cookie_len, gfp);
2345 if (!asoc->peer.cookie)
2346 goto clean_up;
2349 /* RFC 2960 7.2.1 The initial value of ssthresh MAY be arbitrarily
2350 * high (for example, implementations MAY use the size of the receiver
2351 * advertised window).
2353 list_for_each_entry(transport, &asoc->peer.transport_addr_list,
2354 transports) {
2355 transport->ssthresh = asoc->peer.i.a_rwnd;
2358 /* Set up the TSN tracking pieces. */
2359 if (!sctp_tsnmap_init(&asoc->peer.tsn_map, SCTP_TSN_MAP_INITIAL,
2360 asoc->peer.i.initial_tsn, gfp))
2361 goto clean_up;
2363 /* RFC 2960 6.5 Stream Identifier and Stream Sequence Number
2365 * The stream sequence number in all the streams shall start
2366 * from 0 when the association is established. Also, when the
2367 * stream sequence number reaches the value 65535 the next
2368 * stream sequence number shall be set to 0.
2371 /* Allocate storage for the negotiated streams if it is not a temporary
2372 * association.
2374 if (!asoc->temp) {
2375 int error;
2377 asoc->ssnmap = sctp_ssnmap_new(asoc->c.sinit_max_instreams,
2378 asoc->c.sinit_num_ostreams, gfp);
2379 if (!asoc->ssnmap)
2380 goto clean_up;
2382 error = sctp_assoc_set_id(asoc, gfp);
2383 if (error)
2384 goto clean_up;
2387 /* ADDIP Section 4.1 ASCONF Chunk Procedures
2389 * When an endpoint has an ASCONF signaled change to be sent to the
2390 * remote endpoint it should do the following:
2391 * ...
2392 * A2) A serial number should be assigned to the Chunk. The serial
2393 * number should be a monotonically increasing number. All serial
2394 * numbers are defined to be initialized at the start of the
2395 * association to the same value as the Initial TSN.
2397 asoc->peer.addip_serial = asoc->peer.i.initial_tsn - 1;
2398 return 1;
2400 clean_up:
2401 /* Release the transport structures. */
2402 list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
2403 transport = list_entry(pos, struct sctp_transport, transports);
2404 if (transport->state != SCTP_ACTIVE)
2405 sctp_assoc_rm_peer(asoc, transport);
2408 nomem:
2409 return 0;
2413 /* Update asoc with the option described in param.
2415 * RFC2960 3.3.2.1 Optional/Variable Length Parameters in INIT
2417 * asoc is the association to update.
2418 * param is the variable length parameter to use for update.
2419 * cid tells us if this is an INIT, INIT ACK or COOKIE ECHO.
2420 * If the current packet is an INIT we want to minimize the amount of
2421 * work we do. In particular, we should not build transport
2422 * structures for the addresses.
2424 static int sctp_process_param(struct sctp_association *asoc,
2425 union sctp_params param,
2426 const union sctp_addr *peer_addr,
2427 gfp_t gfp)
2429 union sctp_addr addr;
2430 int i;
2431 __u16 sat;
2432 int retval = 1;
2433 sctp_scope_t scope;
2434 time_t stale;
2435 struct sctp_af *af;
2436 union sctp_addr_param *addr_param;
2437 struct sctp_transport *t;
2439 /* We maintain all INIT parameters in network byte order all the
2440 * time. This allows us to not worry about whether the parameters
2441 * came from a fresh INIT, and INIT ACK, or were stored in a cookie.
2443 switch (param.p->type) {
2444 case SCTP_PARAM_IPV6_ADDRESS:
2445 if (PF_INET6 != asoc->base.sk->sk_family)
2446 break;
2447 goto do_addr_param;
2449 case SCTP_PARAM_IPV4_ADDRESS:
2450 /* v4 addresses are not allowed on v6-only socket */
2451 if (ipv6_only_sock(asoc->base.sk))
2452 break;
2453 do_addr_param:
2454 af = sctp_get_af_specific(param_type2af(param.p->type));
2455 af->from_addr_param(&addr, param.addr, htons(asoc->peer.port), 0);
2456 scope = sctp_scope(peer_addr);
2457 if (sctp_in_scope(&addr, scope))
2458 if (!sctp_assoc_add_peer(asoc, &addr, gfp, SCTP_UNCONFIRMED))
2459 return 0;
2460 break;
2462 case SCTP_PARAM_COOKIE_PRESERVATIVE:
2463 if (!sctp_cookie_preserve_enable)
2464 break;
2466 stale = ntohl(param.life->lifespan_increment);
2468 /* Suggested Cookie Life span increment's unit is msec,
2469 * (1/1000sec).
2471 asoc->cookie_life.tv_sec += stale / 1000;
2472 asoc->cookie_life.tv_usec += (stale % 1000) * 1000;
2473 break;
2475 case SCTP_PARAM_HOST_NAME_ADDRESS:
2476 SCTP_DEBUG_PRINTK("unimplemented SCTP_HOST_NAME_ADDRESS\n");
2477 break;
2479 case SCTP_PARAM_SUPPORTED_ADDRESS_TYPES:
2480 /* Turn off the default values first so we'll know which
2481 * ones are really set by the peer.
2483 asoc->peer.ipv4_address = 0;
2484 asoc->peer.ipv6_address = 0;
2486 /* Assume that peer supports the address family
2487 * by which it sends a packet.
2489 if (peer_addr->sa.sa_family == AF_INET6)
2490 asoc->peer.ipv6_address = 1;
2491 else if (peer_addr->sa.sa_family == AF_INET)
2492 asoc->peer.ipv4_address = 1;
2494 /* Cycle through address types; avoid divide by 0. */
2495 sat = ntohs(param.p->length) - sizeof(sctp_paramhdr_t);
2496 if (sat)
2497 sat /= sizeof(__u16);
2499 for (i = 0; i < sat; ++i) {
2500 switch (param.sat->types[i]) {
2501 case SCTP_PARAM_IPV4_ADDRESS:
2502 asoc->peer.ipv4_address = 1;
2503 break;
2505 case SCTP_PARAM_IPV6_ADDRESS:
2506 if (PF_INET6 == asoc->base.sk->sk_family)
2507 asoc->peer.ipv6_address = 1;
2508 break;
2510 case SCTP_PARAM_HOST_NAME_ADDRESS:
2511 asoc->peer.hostname_address = 1;
2512 break;
2514 default: /* Just ignore anything else. */
2515 break;
2518 break;
2520 case SCTP_PARAM_STATE_COOKIE:
2521 asoc->peer.cookie_len =
2522 ntohs(param.p->length) - sizeof(sctp_paramhdr_t);
2523 asoc->peer.cookie = param.cookie->body;
2524 break;
2526 case SCTP_PARAM_HEARTBEAT_INFO:
2527 /* Would be odd to receive, but it causes no problems. */
2528 break;
2530 case SCTP_PARAM_UNRECOGNIZED_PARAMETERS:
2531 /* Rejected during verify stage. */
2532 break;
2534 case SCTP_PARAM_ECN_CAPABLE:
2535 asoc->peer.ecn_capable = 1;
2536 break;
2538 case SCTP_PARAM_ADAPTATION_LAYER_IND:
2539 asoc->peer.adaptation_ind = ntohl(param.aind->adaptation_ind);
2540 break;
2542 case SCTP_PARAM_SET_PRIMARY:
2543 if (!sctp_addip_enable)
2544 goto fall_through;
2546 addr_param = param.v + sizeof(sctp_addip_param_t);
2548 af = sctp_get_af_specific(param_type2af(param.p->type));
2549 af->from_addr_param(&addr, addr_param,
2550 htons(asoc->peer.port), 0);
2552 /* if the address is invalid, we can't process it.
2553 * XXX: see spec for what to do.
2555 if (!af->addr_valid(&addr, NULL, NULL))
2556 break;
2558 t = sctp_assoc_lookup_paddr(asoc, &addr);
2559 if (!t)
2560 break;
2562 sctp_assoc_set_primary(asoc, t);
2563 break;
2565 case SCTP_PARAM_SUPPORTED_EXT:
2566 sctp_process_ext_param(asoc, param);
2567 break;
2569 case SCTP_PARAM_FWD_TSN_SUPPORT:
2570 if (sctp_prsctp_enable) {
2571 asoc->peer.prsctp_capable = 1;
2572 break;
2574 /* Fall Through */
2575 goto fall_through;
2577 case SCTP_PARAM_RANDOM:
2578 if (!sctp_auth_enable)
2579 goto fall_through;
2581 /* Save peer's random parameter */
2582 asoc->peer.peer_random = kmemdup(param.p,
2583 ntohs(param.p->length), gfp);
2584 if (!asoc->peer.peer_random) {
2585 retval = 0;
2586 break;
2588 break;
2590 case SCTP_PARAM_HMAC_ALGO:
2591 if (!sctp_auth_enable)
2592 goto fall_through;
2594 /* Save peer's HMAC list */
2595 asoc->peer.peer_hmacs = kmemdup(param.p,
2596 ntohs(param.p->length), gfp);
2597 if (!asoc->peer.peer_hmacs) {
2598 retval = 0;
2599 break;
2602 /* Set the default HMAC the peer requested*/
2603 sctp_auth_asoc_set_default_hmac(asoc, param.hmac_algo);
2604 break;
2606 case SCTP_PARAM_CHUNKS:
2607 if (!sctp_auth_enable)
2608 goto fall_through;
2610 asoc->peer.peer_chunks = kmemdup(param.p,
2611 ntohs(param.p->length), gfp);
2612 if (!asoc->peer.peer_chunks)
2613 retval = 0;
2614 break;
2615 fall_through:
2616 default:
2617 /* Any unrecognized parameters should have been caught
2618 * and handled by sctp_verify_param() which should be
2619 * called prior to this routine. Simply log the error
2620 * here.
2622 SCTP_DEBUG_PRINTK("Ignoring param: %d for association %p.\n",
2623 ntohs(param.p->type), asoc);
2624 break;
2627 return retval;
2630 /* Select a new verification tag. */
2631 __u32 sctp_generate_tag(const struct sctp_endpoint *ep)
2633 /* I believe that this random number generator complies with RFC1750.
2634 * A tag of 0 is reserved for special cases (e.g. INIT).
2636 __u32 x;
2638 do {
2639 get_random_bytes(&x, sizeof(__u32));
2640 } while (x == 0);
2642 return x;
2645 /* Select an initial TSN to send during startup. */
2646 __u32 sctp_generate_tsn(const struct sctp_endpoint *ep)
2648 __u32 retval;
2650 get_random_bytes(&retval, sizeof(__u32));
2651 return retval;
2655 * ADDIP 3.1.1 Address Configuration Change Chunk (ASCONF)
2656 * 0 1 2 3
2657 * 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
2658 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2659 * | Type = 0xC1 | Chunk Flags | Chunk Length |
2660 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2661 * | Serial Number |
2662 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2663 * | Address Parameter |
2664 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2665 * | ASCONF Parameter #1 |
2666 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2667 * \ \
2668 * / .... /
2669 * \ \
2670 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2671 * | ASCONF Parameter #N |
2672 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2674 * Address Parameter and other parameter will not be wrapped in this function
2676 static struct sctp_chunk *sctp_make_asconf(struct sctp_association *asoc,
2677 union sctp_addr *addr,
2678 int vparam_len)
2680 sctp_addiphdr_t asconf;
2681 struct sctp_chunk *retval;
2682 int length = sizeof(asconf) + vparam_len;
2683 union sctp_addr_param addrparam;
2684 int addrlen;
2685 struct sctp_af *af = sctp_get_af_specific(addr->v4.sin_family);
2687 addrlen = af->to_addr_param(addr, &addrparam);
2688 if (!addrlen)
2689 return NULL;
2690 length += addrlen;
2692 /* Create the chunk. */
2693 retval = sctp_make_chunk(asoc, SCTP_CID_ASCONF, 0, length);
2694 if (!retval)
2695 return NULL;
2697 asconf.serial = htonl(asoc->addip_serial++);
2699 retval->subh.addip_hdr =
2700 sctp_addto_chunk(retval, sizeof(asconf), &asconf);
2701 retval->param_hdr.v =
2702 sctp_addto_chunk(retval, addrlen, &addrparam);
2704 return retval;
2707 /* ADDIP
2708 * 3.2.1 Add IP Address
2709 * 0 1 2 3
2710 * 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
2711 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2712 * | Type = 0xC001 | Length = Variable |
2713 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2714 * | ASCONF-Request Correlation ID |
2715 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2716 * | Address Parameter |
2717 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2719 * 3.2.2 Delete IP Address
2720 * 0 1 2 3
2721 * 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
2722 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2723 * | Type = 0xC002 | Length = Variable |
2724 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2725 * | ASCONF-Request Correlation ID |
2726 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2727 * | Address Parameter |
2728 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2731 struct sctp_chunk *sctp_make_asconf_update_ip(struct sctp_association *asoc,
2732 union sctp_addr *laddr,
2733 struct sockaddr *addrs,
2734 int addrcnt,
2735 __be16 flags)
2737 sctp_addip_param_t param;
2738 struct sctp_chunk *retval;
2739 union sctp_addr_param addr_param;
2740 union sctp_addr *addr;
2741 void *addr_buf;
2742 struct sctp_af *af;
2743 int paramlen = sizeof(param);
2744 int addr_param_len = 0;
2745 int totallen = 0;
2746 int i;
2748 /* Get total length of all the address parameters. */
2749 addr_buf = addrs;
2750 for (i = 0; i < addrcnt; i++) {
2751 addr = (union sctp_addr *)addr_buf;
2752 af = sctp_get_af_specific(addr->v4.sin_family);
2753 addr_param_len = af->to_addr_param(addr, &addr_param);
2755 totallen += paramlen;
2756 totallen += addr_param_len;
2758 addr_buf += af->sockaddr_len;
2761 /* Create an asconf chunk with the required length. */
2762 retval = sctp_make_asconf(asoc, laddr, totallen);
2763 if (!retval)
2764 return NULL;
2766 /* Add the address parameters to the asconf chunk. */
2767 addr_buf = addrs;
2768 for (i = 0; i < addrcnt; i++) {
2769 addr = (union sctp_addr *)addr_buf;
2770 af = sctp_get_af_specific(addr->v4.sin_family);
2771 addr_param_len = af->to_addr_param(addr, &addr_param);
2772 param.param_hdr.type = flags;
2773 param.param_hdr.length = htons(paramlen + addr_param_len);
2774 param.crr_id = i;
2776 sctp_addto_chunk(retval, paramlen, &param);
2777 sctp_addto_chunk(retval, addr_param_len, &addr_param);
2779 addr_buf += af->sockaddr_len;
2781 return retval;
2784 /* ADDIP
2785 * 3.2.4 Set Primary IP Address
2786 * 0 1 2 3
2787 * 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
2788 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2789 * | Type =0xC004 | Length = Variable |
2790 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2791 * | ASCONF-Request Correlation ID |
2792 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2793 * | Address Parameter |
2794 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2796 * Create an ASCONF chunk with Set Primary IP address parameter.
2798 struct sctp_chunk *sctp_make_asconf_set_prim(struct sctp_association *asoc,
2799 union sctp_addr *addr)
2801 sctp_addip_param_t param;
2802 struct sctp_chunk *retval;
2803 int len = sizeof(param);
2804 union sctp_addr_param addrparam;
2805 int addrlen;
2806 struct sctp_af *af = sctp_get_af_specific(addr->v4.sin_family);
2808 addrlen = af->to_addr_param(addr, &addrparam);
2809 if (!addrlen)
2810 return NULL;
2811 len += addrlen;
2813 /* Create the chunk and make asconf header. */
2814 retval = sctp_make_asconf(asoc, addr, len);
2815 if (!retval)
2816 return NULL;
2818 param.param_hdr.type = SCTP_PARAM_SET_PRIMARY;
2819 param.param_hdr.length = htons(len);
2820 param.crr_id = 0;
2822 sctp_addto_chunk(retval, sizeof(param), &param);
2823 sctp_addto_chunk(retval, addrlen, &addrparam);
2825 return retval;
2828 /* ADDIP 3.1.2 Address Configuration Acknowledgement Chunk (ASCONF-ACK)
2829 * 0 1 2 3
2830 * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
2831 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2832 * | Type = 0x80 | Chunk Flags | Chunk Length |
2833 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2834 * | Serial Number |
2835 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2836 * | ASCONF Parameter Response#1 |
2837 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2838 * \ \
2839 * / .... /
2840 * \ \
2841 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2842 * | ASCONF Parameter Response#N |
2843 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2845 * Create an ASCONF_ACK chunk with enough space for the parameter responses.
2847 static struct sctp_chunk *sctp_make_asconf_ack(const struct sctp_association *asoc,
2848 __u32 serial, int vparam_len)
2850 sctp_addiphdr_t asconf;
2851 struct sctp_chunk *retval;
2852 int length = sizeof(asconf) + vparam_len;
2854 /* Create the chunk. */
2855 retval = sctp_make_chunk(asoc, SCTP_CID_ASCONF_ACK, 0, length);
2856 if (!retval)
2857 return NULL;
2859 asconf.serial = htonl(serial);
2861 retval->subh.addip_hdr =
2862 sctp_addto_chunk(retval, sizeof(asconf), &asconf);
2864 return retval;
2867 /* Add response parameters to an ASCONF_ACK chunk. */
2868 static void sctp_add_asconf_response(struct sctp_chunk *chunk, __be32 crr_id,
2869 __be16 err_code, sctp_addip_param_t *asconf_param)
2871 sctp_addip_param_t ack_param;
2872 sctp_errhdr_t err_param;
2873 int asconf_param_len = 0;
2874 int err_param_len = 0;
2875 __be16 response_type;
2877 if (SCTP_ERROR_NO_ERROR == err_code) {
2878 response_type = SCTP_PARAM_SUCCESS_REPORT;
2879 } else {
2880 response_type = SCTP_PARAM_ERR_CAUSE;
2881 err_param_len = sizeof(err_param);
2882 if (asconf_param)
2883 asconf_param_len =
2884 ntohs(asconf_param->param_hdr.length);
2887 /* Add Success Indication or Error Cause Indication parameter. */
2888 ack_param.param_hdr.type = response_type;
2889 ack_param.param_hdr.length = htons(sizeof(ack_param) +
2890 err_param_len +
2891 asconf_param_len);
2892 ack_param.crr_id = crr_id;
2893 sctp_addto_chunk(chunk, sizeof(ack_param), &ack_param);
2895 if (SCTP_ERROR_NO_ERROR == err_code)
2896 return;
2898 /* Add Error Cause parameter. */
2899 err_param.cause = err_code;
2900 err_param.length = htons(err_param_len + asconf_param_len);
2901 sctp_addto_chunk(chunk, err_param_len, &err_param);
2903 /* Add the failed TLV copied from ASCONF chunk. */
2904 if (asconf_param)
2905 sctp_addto_chunk(chunk, asconf_param_len, asconf_param);
2908 /* Process a asconf parameter. */
2909 static __be16 sctp_process_asconf_param(struct sctp_association *asoc,
2910 struct sctp_chunk *asconf,
2911 sctp_addip_param_t *asconf_param)
2913 struct sctp_transport *peer;
2914 struct sctp_af *af;
2915 union sctp_addr addr;
2916 union sctp_addr_param *addr_param;
2918 addr_param = (union sctp_addr_param *)
2919 ((void *)asconf_param + sizeof(sctp_addip_param_t));
2921 if (asconf_param->param_hdr.type != SCTP_PARAM_ADD_IP &&
2922 asconf_param->param_hdr.type != SCTP_PARAM_DEL_IP &&
2923 asconf_param->param_hdr.type != SCTP_PARAM_SET_PRIMARY)
2924 return SCTP_ERROR_UNKNOWN_PARAM;
2926 switch (addr_param->v4.param_hdr.type) {
2927 case SCTP_PARAM_IPV6_ADDRESS:
2928 if (!asoc->peer.ipv6_address)
2929 return SCTP_ERROR_DNS_FAILED;
2930 break;
2931 case SCTP_PARAM_IPV4_ADDRESS:
2932 if (!asoc->peer.ipv4_address)
2933 return SCTP_ERROR_DNS_FAILED;
2934 break;
2935 default:
2936 return SCTP_ERROR_DNS_FAILED;
2939 af = sctp_get_af_specific(param_type2af(addr_param->v4.param_hdr.type));
2940 if (unlikely(!af))
2941 return SCTP_ERROR_DNS_FAILED;
2943 af->from_addr_param(&addr, addr_param, htons(asoc->peer.port), 0);
2945 /* ADDIP 4.2.1 This parameter MUST NOT contain a broadcast
2946 * or multicast address.
2947 * (note: wildcard is permitted and requires special handling so
2948 * make sure we check for that)
2950 if (!af->is_any(&addr) && !af->addr_valid(&addr, NULL, asconf->skb))
2951 return SCTP_ERROR_DNS_FAILED;
2953 switch (asconf_param->param_hdr.type) {
2954 case SCTP_PARAM_ADD_IP:
2955 /* Section 4.2.1:
2956 * If the address 0.0.0.0 or ::0 is provided, the source
2957 * address of the packet MUST be added.
2959 if (af->is_any(&addr))
2960 memcpy(&addr, &asconf->source, sizeof(addr));
2962 /* ADDIP 4.3 D9) If an endpoint receives an ADD IP address
2963 * request and does not have the local resources to add this
2964 * new address to the association, it MUST return an Error
2965 * Cause TLV set to the new error code 'Operation Refused
2966 * Due to Resource Shortage'.
2969 peer = sctp_assoc_add_peer(asoc, &addr, GFP_ATOMIC, SCTP_UNCONFIRMED);
2970 if (!peer)
2971 return SCTP_ERROR_RSRC_LOW;
2973 /* Start the heartbeat timer. */
2974 if (!mod_timer(&peer->hb_timer, sctp_transport_timeout(peer)))
2975 sctp_transport_hold(peer);
2976 break;
2977 case SCTP_PARAM_DEL_IP:
2978 /* ADDIP 4.3 D7) If a request is received to delete the
2979 * last remaining IP address of a peer endpoint, the receiver
2980 * MUST send an Error Cause TLV with the error cause set to the
2981 * new error code 'Request to Delete Last Remaining IP Address'.
2983 if (asoc->peer.transport_count == 1)
2984 return SCTP_ERROR_DEL_LAST_IP;
2986 /* ADDIP 4.3 D8) If a request is received to delete an IP
2987 * address which is also the source address of the IP packet
2988 * which contained the ASCONF chunk, the receiver MUST reject
2989 * this request. To reject the request the receiver MUST send
2990 * an Error Cause TLV set to the new error code 'Request to
2991 * Delete Source IP Address'
2993 if (sctp_cmp_addr_exact(sctp_source(asconf), &addr))
2994 return SCTP_ERROR_DEL_SRC_IP;
2996 /* Section 4.2.2
2997 * If the address 0.0.0.0 or ::0 is provided, all
2998 * addresses of the peer except the source address of the
2999 * packet MUST be deleted.
3001 if (af->is_any(&addr)) {
3002 sctp_assoc_set_primary(asoc, asconf->transport);
3003 sctp_assoc_del_nonprimary_peers(asoc,
3004 asconf->transport);
3005 } else
3006 sctp_assoc_del_peer(asoc, &addr);
3007 break;
3008 case SCTP_PARAM_SET_PRIMARY:
3009 /* ADDIP Section 4.2.4
3010 * If the address 0.0.0.0 or ::0 is provided, the receiver
3011 * MAY mark the source address of the packet as its
3012 * primary.
3014 if (af->is_any(&addr))
3015 memcpy(&addr.v4, sctp_source(asconf), sizeof(addr));
3017 peer = sctp_assoc_lookup_paddr(asoc, &addr);
3018 if (!peer)
3019 return SCTP_ERROR_DNS_FAILED;
3021 sctp_assoc_set_primary(asoc, peer);
3022 break;
3025 return SCTP_ERROR_NO_ERROR;
3028 /* Verify the ASCONF packet before we process it. */
3029 int sctp_verify_asconf(const struct sctp_association *asoc,
3030 struct sctp_paramhdr *param_hdr, void *chunk_end,
3031 struct sctp_paramhdr **errp) {
3032 sctp_addip_param_t *asconf_param;
3033 union sctp_params param;
3034 int length, plen;
3036 param.v = (sctp_paramhdr_t *) param_hdr;
3037 while (param.v <= chunk_end - sizeof(sctp_paramhdr_t)) {
3038 length = ntohs(param.p->length);
3039 *errp = param.p;
3041 if (param.v > chunk_end - length ||
3042 length < sizeof(sctp_paramhdr_t))
3043 return 0;
3045 switch (param.p->type) {
3046 case SCTP_PARAM_ADD_IP:
3047 case SCTP_PARAM_DEL_IP:
3048 case SCTP_PARAM_SET_PRIMARY:
3049 asconf_param = (sctp_addip_param_t *)param.v;
3050 plen = ntohs(asconf_param->param_hdr.length);
3051 if (plen < sizeof(sctp_addip_param_t) +
3052 sizeof(sctp_paramhdr_t))
3053 return 0;
3054 break;
3055 case SCTP_PARAM_SUCCESS_REPORT:
3056 case SCTP_PARAM_ADAPTATION_LAYER_IND:
3057 if (length != sizeof(sctp_addip_param_t))
3058 return 0;
3060 break;
3061 default:
3062 break;
3065 param.v += WORD_ROUND(length);
3068 if (param.v != chunk_end)
3069 return 0;
3071 return 1;
3074 /* Process an incoming ASCONF chunk with the next expected serial no. and
3075 * return an ASCONF_ACK chunk to be sent in response.
3077 struct sctp_chunk *sctp_process_asconf(struct sctp_association *asoc,
3078 struct sctp_chunk *asconf)
3080 sctp_addiphdr_t *hdr;
3081 union sctp_addr_param *addr_param;
3082 sctp_addip_param_t *asconf_param;
3083 struct sctp_chunk *asconf_ack;
3085 __be16 err_code;
3086 int length = 0;
3087 int chunk_len;
3088 __u32 serial;
3089 int all_param_pass = 1;
3091 chunk_len = ntohs(asconf->chunk_hdr->length) - sizeof(sctp_chunkhdr_t);
3092 hdr = (sctp_addiphdr_t *)asconf->skb->data;
3093 serial = ntohl(hdr->serial);
3095 /* Skip the addiphdr and store a pointer to address parameter. */
3096 length = sizeof(sctp_addiphdr_t);
3097 addr_param = (union sctp_addr_param *)(asconf->skb->data + length);
3098 chunk_len -= length;
3100 /* Skip the address parameter and store a pointer to the first
3101 * asconf parameter.
3103 length = ntohs(addr_param->v4.param_hdr.length);
3104 asconf_param = (sctp_addip_param_t *)((void *)addr_param + length);
3105 chunk_len -= length;
3107 /* create an ASCONF_ACK chunk.
3108 * Based on the definitions of parameters, we know that the size of
3109 * ASCONF_ACK parameters are less than or equal to the twice of ASCONF
3110 * parameters.
3112 asconf_ack = sctp_make_asconf_ack(asoc, serial, chunk_len * 2);
3113 if (!asconf_ack)
3114 goto done;
3116 /* Process the TLVs contained within the ASCONF chunk. */
3117 while (chunk_len > 0) {
3118 err_code = sctp_process_asconf_param(asoc, asconf,
3119 asconf_param);
3120 /* ADDIP 4.1 A7)
3121 * If an error response is received for a TLV parameter,
3122 * all TLVs with no response before the failed TLV are
3123 * considered successful if not reported. All TLVs after
3124 * the failed response are considered unsuccessful unless
3125 * a specific success indication is present for the parameter.
3127 if (SCTP_ERROR_NO_ERROR != err_code)
3128 all_param_pass = 0;
3130 if (!all_param_pass)
3131 sctp_add_asconf_response(asconf_ack,
3132 asconf_param->crr_id, err_code,
3133 asconf_param);
3135 /* ADDIP 4.3 D11) When an endpoint receiving an ASCONF to add
3136 * an IP address sends an 'Out of Resource' in its response, it
3137 * MUST also fail any subsequent add or delete requests bundled
3138 * in the ASCONF.
3140 if (SCTP_ERROR_RSRC_LOW == err_code)
3141 goto done;
3143 /* Move to the next ASCONF param. */
3144 length = ntohs(asconf_param->param_hdr.length);
3145 asconf_param = (sctp_addip_param_t *)((void *)asconf_param +
3146 length);
3147 chunk_len -= length;
3150 done:
3151 asoc->peer.addip_serial++;
3153 /* If we are sending a new ASCONF_ACK hold a reference to it in assoc
3154 * after freeing the reference to old asconf ack if any.
3156 if (asconf_ack) {
3157 sctp_chunk_hold(asconf_ack);
3158 list_add_tail(&asconf_ack->transmitted_list,
3159 &asoc->asconf_ack_list);
3162 return asconf_ack;
3165 /* Process a asconf parameter that is successfully acked. */
3166 static void sctp_asconf_param_success(struct sctp_association *asoc,
3167 sctp_addip_param_t *asconf_param)
3169 struct sctp_af *af;
3170 union sctp_addr addr;
3171 struct sctp_bind_addr *bp = &asoc->base.bind_addr;
3172 union sctp_addr_param *addr_param;
3173 struct sctp_transport *transport;
3174 struct sctp_sockaddr_entry *saddr;
3176 addr_param = (union sctp_addr_param *)
3177 ((void *)asconf_param + sizeof(sctp_addip_param_t));
3179 /* We have checked the packet before, so we do not check again. */
3180 af = sctp_get_af_specific(param_type2af(addr_param->v4.param_hdr.type));
3181 af->from_addr_param(&addr, addr_param, htons(bp->port), 0);
3183 switch (asconf_param->param_hdr.type) {
3184 case SCTP_PARAM_ADD_IP:
3185 /* This is always done in BH context with a socket lock
3186 * held, so the list can not change.
3188 local_bh_disable();
3189 list_for_each_entry(saddr, &bp->address_list, list) {
3190 if (sctp_cmp_addr_exact(&saddr->a, &addr))
3191 saddr->state = SCTP_ADDR_SRC;
3193 local_bh_enable();
3194 list_for_each_entry(transport, &asoc->peer.transport_addr_list,
3195 transports) {
3196 if (transport->state == SCTP_ACTIVE)
3197 continue;
3198 dst_release(transport->dst);
3199 sctp_transport_route(transport, NULL,
3200 sctp_sk(asoc->base.sk));
3202 break;
3203 case SCTP_PARAM_DEL_IP:
3204 local_bh_disable();
3205 sctp_del_bind_addr(bp, &addr);
3206 local_bh_enable();
3207 list_for_each_entry(transport, &asoc->peer.transport_addr_list,
3208 transports) {
3209 dst_release(transport->dst);
3210 sctp_transport_route(transport, NULL,
3211 sctp_sk(asoc->base.sk));
3213 break;
3214 default:
3215 break;
3219 /* Get the corresponding ASCONF response error code from the ASCONF_ACK chunk
3220 * for the given asconf parameter. If there is no response for this parameter,
3221 * return the error code based on the third argument 'no_err'.
3222 * ADDIP 4.1
3223 * A7) If an error response is received for a TLV parameter, all TLVs with no
3224 * response before the failed TLV are considered successful if not reported.
3225 * All TLVs after the failed response are considered unsuccessful unless a
3226 * specific success indication is present for the parameter.
3228 static __be16 sctp_get_asconf_response(struct sctp_chunk *asconf_ack,
3229 sctp_addip_param_t *asconf_param,
3230 int no_err)
3232 sctp_addip_param_t *asconf_ack_param;
3233 sctp_errhdr_t *err_param;
3234 int length;
3235 int asconf_ack_len;
3236 __be16 err_code;
3238 if (no_err)
3239 err_code = SCTP_ERROR_NO_ERROR;
3240 else
3241 err_code = SCTP_ERROR_REQ_REFUSED;
3243 asconf_ack_len = ntohs(asconf_ack->chunk_hdr->length) -
3244 sizeof(sctp_chunkhdr_t);
3246 /* Skip the addiphdr from the asconf_ack chunk and store a pointer to
3247 * the first asconf_ack parameter.
3249 length = sizeof(sctp_addiphdr_t);
3250 asconf_ack_param = (sctp_addip_param_t *)(asconf_ack->skb->data +
3251 length);
3252 asconf_ack_len -= length;
3254 while (asconf_ack_len > 0) {
3255 if (asconf_ack_param->crr_id == asconf_param->crr_id) {
3256 switch(asconf_ack_param->param_hdr.type) {
3257 case SCTP_PARAM_SUCCESS_REPORT:
3258 return SCTP_ERROR_NO_ERROR;
3259 case SCTP_PARAM_ERR_CAUSE:
3260 length = sizeof(sctp_addip_param_t);
3261 err_param = (sctp_errhdr_t *)
3262 ((void *)asconf_ack_param + length);
3263 asconf_ack_len -= length;
3264 if (asconf_ack_len > 0)
3265 return err_param->cause;
3266 else
3267 return SCTP_ERROR_INV_PARAM;
3268 break;
3269 default:
3270 return SCTP_ERROR_INV_PARAM;
3274 length = ntohs(asconf_ack_param->param_hdr.length);
3275 asconf_ack_param = (sctp_addip_param_t *)
3276 ((void *)asconf_ack_param + length);
3277 asconf_ack_len -= length;
3280 return err_code;
3283 /* Process an incoming ASCONF_ACK chunk against the cached last ASCONF chunk. */
3284 int sctp_process_asconf_ack(struct sctp_association *asoc,
3285 struct sctp_chunk *asconf_ack)
3287 struct sctp_chunk *asconf = asoc->addip_last_asconf;
3288 union sctp_addr_param *addr_param;
3289 sctp_addip_param_t *asconf_param;
3290 int length = 0;
3291 int asconf_len = asconf->skb->len;
3292 int all_param_pass = 0;
3293 int no_err = 1;
3294 int retval = 0;
3295 __be16 err_code = SCTP_ERROR_NO_ERROR;
3297 /* Skip the chunkhdr and addiphdr from the last asconf sent and store
3298 * a pointer to address parameter.
3300 length = sizeof(sctp_addip_chunk_t);
3301 addr_param = (union sctp_addr_param *)(asconf->skb->data + length);
3302 asconf_len -= length;
3304 /* Skip the address parameter in the last asconf sent and store a
3305 * pointer to the first asconf parameter.
3307 length = ntohs(addr_param->v4.param_hdr.length);
3308 asconf_param = (sctp_addip_param_t *)((void *)addr_param + length);
3309 asconf_len -= length;
3311 /* ADDIP 4.1
3312 * A8) If there is no response(s) to specific TLV parameter(s), and no
3313 * failures are indicated, then all request(s) are considered
3314 * successful.
3316 if (asconf_ack->skb->len == sizeof(sctp_addiphdr_t))
3317 all_param_pass = 1;
3319 /* Process the TLVs contained in the last sent ASCONF chunk. */
3320 while (asconf_len > 0) {
3321 if (all_param_pass)
3322 err_code = SCTP_ERROR_NO_ERROR;
3323 else {
3324 err_code = sctp_get_asconf_response(asconf_ack,
3325 asconf_param,
3326 no_err);
3327 if (no_err && (SCTP_ERROR_NO_ERROR != err_code))
3328 no_err = 0;
3331 switch (err_code) {
3332 case SCTP_ERROR_NO_ERROR:
3333 sctp_asconf_param_success(asoc, asconf_param);
3334 break;
3336 case SCTP_ERROR_RSRC_LOW:
3337 retval = 1;
3338 break;
3340 case SCTP_ERROR_UNKNOWN_PARAM:
3341 /* Disable sending this type of asconf parameter in
3342 * future.
3344 asoc->peer.addip_disabled_mask |=
3345 asconf_param->param_hdr.type;
3346 break;
3348 case SCTP_ERROR_REQ_REFUSED:
3349 case SCTP_ERROR_DEL_LAST_IP:
3350 case SCTP_ERROR_DEL_SRC_IP:
3351 default:
3352 break;
3355 /* Skip the processed asconf parameter and move to the next
3356 * one.
3358 length = ntohs(asconf_param->param_hdr.length);
3359 asconf_param = (sctp_addip_param_t *)((void *)asconf_param +
3360 length);
3361 asconf_len -= length;
3364 /* Free the cached last sent asconf chunk. */
3365 list_del_init(&asconf->transmitted_list);
3366 sctp_chunk_free(asconf);
3367 asoc->addip_last_asconf = NULL;
3369 return retval;
3372 /* Make a FWD TSN chunk. */
3373 struct sctp_chunk *sctp_make_fwdtsn(const struct sctp_association *asoc,
3374 __u32 new_cum_tsn, size_t nstreams,
3375 struct sctp_fwdtsn_skip *skiplist)
3377 struct sctp_chunk *retval = NULL;
3378 struct sctp_fwdtsn_chunk *ftsn_chunk;
3379 struct sctp_fwdtsn_hdr ftsn_hdr;
3380 struct sctp_fwdtsn_skip skip;
3381 size_t hint;
3382 int i;
3384 hint = (nstreams + 1) * sizeof(__u32);
3386 retval = sctp_make_chunk(asoc, SCTP_CID_FWD_TSN, 0, hint);
3388 if (!retval)
3389 return NULL;
3391 ftsn_chunk = (struct sctp_fwdtsn_chunk *)retval->subh.fwdtsn_hdr;
3393 ftsn_hdr.new_cum_tsn = htonl(new_cum_tsn);
3394 retval->subh.fwdtsn_hdr =
3395 sctp_addto_chunk(retval, sizeof(ftsn_hdr), &ftsn_hdr);
3397 for (i = 0; i < nstreams; i++) {
3398 skip.stream = skiplist[i].stream;
3399 skip.ssn = skiplist[i].ssn;
3400 sctp_addto_chunk(retval, sizeof(skip), &skip);
3403 return retval;