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)
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
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>
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>
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 static struct sctp_chunk *sctp_make_chunk(const struct sctp_association *asoc,
72 __u8 type, __u8 flags, int paylen);
73 static sctp_cookie_param_t *sctp_pack_cookie(const struct sctp_endpoint *ep,
74 const struct sctp_association *asoc,
75 const struct sctp_chunk *init_chunk,
77 const __u8 *raw_addrs, int addrs_len);
78 static int sctp_process_param(struct sctp_association *asoc,
79 union sctp_params param,
80 const union sctp_addr *peer_addr,
82 static void *sctp_addto_param(struct sctp_chunk *chunk, int len,
85 /* What was the inbound interface for this chunk? */
86 int sctp_chunk_iif(const struct sctp_chunk *chunk)
91 af = sctp_get_af_specific(ipver2af(ip_hdr(chunk->skb)->version));
93 iif = af->skb_iif(chunk->skb);
98 /* RFC 2960 3.3.2 Initiation (INIT) (1)
100 * Note 2: The ECN capable field is reserved for future use of
101 * Explicit Congestion Notification.
103 static const struct sctp_paramhdr ecap_param = {
104 SCTP_PARAM_ECN_CAPABLE,
105 cpu_to_be16(sizeof(struct sctp_paramhdr)),
107 static const struct sctp_paramhdr prsctp_param = {
108 SCTP_PARAM_FWD_TSN_SUPPORT,
109 cpu_to_be16(sizeof(struct sctp_paramhdr)),
112 /* A helper to initialize an op error inside a
113 * provided chunk, as most cause codes will be embedded inside an
116 void sctp_init_cause(struct sctp_chunk *chunk, __be16 cause_code,
122 /* Cause code constants are now defined in network order. */
123 err.cause = cause_code;
124 len = sizeof(sctp_errhdr_t) + paylen;
125 err.length = htons(len);
126 chunk->subh.err_hdr = sctp_addto_chunk(chunk, sizeof(sctp_errhdr_t), &err);
129 /* A helper to initialize an op error inside a
130 * provided chunk, as most cause codes will be embedded inside an
131 * abort chunk. Differs from sctp_init_cause in that it won't oops
132 * if there isn't enough space in the op error chunk
134 static int sctp_init_cause_fixed(struct sctp_chunk *chunk, __be16 cause_code,
140 /* Cause code constants are now defined in network order. */
141 err.cause = cause_code;
142 len = sizeof(sctp_errhdr_t) + paylen;
143 err.length = htons(len);
145 if (skb_tailroom(chunk->skb) < len)
147 chunk->subh.err_hdr = sctp_addto_chunk_fixed(chunk,
148 sizeof(sctp_errhdr_t),
152 /* 3.3.2 Initiation (INIT) (1)
154 * This chunk is used to initiate a SCTP association between two
155 * endpoints. The format of the INIT chunk is shown below:
158 * 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
159 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
160 * | Type = 1 | Chunk Flags | Chunk Length |
161 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
163 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
164 * | Advertised Receiver Window Credit (a_rwnd) |
165 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
166 * | Number of Outbound Streams | Number of Inbound Streams |
167 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
169 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
171 * / Optional/Variable-Length Parameters /
173 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
176 * The INIT chunk contains the following parameters. Unless otherwise
177 * noted, each parameter MUST only be included once in the INIT chunk.
179 * Fixed Parameters Status
180 * ----------------------------------------------
181 * Initiate Tag Mandatory
182 * Advertised Receiver Window Credit Mandatory
183 * Number of Outbound Streams Mandatory
184 * Number of Inbound Streams Mandatory
185 * Initial TSN Mandatory
187 * Variable Parameters Status Type Value
188 * -------------------------------------------------------------
189 * IPv4 Address (Note 1) Optional 5
190 * IPv6 Address (Note 1) Optional 6
191 * Cookie Preservative Optional 9
192 * Reserved for ECN Capable (Note 2) Optional 32768 (0x8000)
193 * Host Name Address (Note 3) Optional 11
194 * Supported Address Types (Note 4) Optional 12
196 struct sctp_chunk *sctp_make_init(const struct sctp_association *asoc,
197 const struct sctp_bind_addr *bp,
198 gfp_t gfp, int vparam_len)
200 struct net *net = sock_net(asoc->base.sk);
202 union sctp_params addrs;
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;
209 sctp_adaptation_ind_param_t aiparam;
210 sctp_supported_ext_param_t ext_param;
213 sctp_paramhdr_t *auth_chunks = 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.
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 (net->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 (net->sctp.addip_enable) {
249 extensions[num_ext] = SCTP_CID_ASCONF;
250 extensions[num_ext+1] = SCTP_CID_ASCONF_ACK;
254 if (sp->adaptation_ind)
255 chunksize += sizeof(aiparam);
257 chunksize += vparam_len;
259 /* Account for AUTH related parameters */
260 if (net->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));
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));
278 extensions[num_ext] = SCTP_CID_AUTH;
282 /* If we have any extensions to report, account for that */
284 chunksize += WORD_ROUND(sizeof(sctp_supported_ext_param_t) +
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);
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
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),
331 sctp_addto_param(retval, num_ext, extensions);
334 if (net->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 (net->sctp.auth_enable) {
346 sctp_addto_chunk(retval, sizeof(asoc->c.auth_random),
347 asoc->c.auth_random);
349 sctp_addto_chunk(retval, ntohs(auth_hmacs->length),
352 sctp_addto_chunk(retval, ntohs(auth_chunks->length),
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;
369 sctp_cookie_param_t *cookie;
372 sctp_adaptation_ind_param_t aiparam;
373 sctp_supported_ext_param_t ext_param;
376 sctp_paramhdr_t *auth_chunks = 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,
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;
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));
431 auth_chunks = (sctp_paramhdr_t *)asoc->c.auth_chunks;
432 if (auth_chunks->length)
433 chunksize += WORD_ROUND(ntohs(auth_chunks->length));
437 extensions[num_ext] = SCTP_CID_AUTH;
442 chunksize += WORD_ROUND(sizeof(sctp_supported_ext_param_t) +
445 /* Now allocate and fill out the chunk. */
446 retval = sctp_make_chunk(asoc, SCTP_CID_INIT_ACK, 0, chunksize);
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);
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),
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),
489 sctp_addto_chunk(retval, ntohs(auth_hmacs->length),
492 sctp_addto_chunk(retval, ntohs(auth_chunks->length),
496 /* We need to remove the const qualifier at this point. */
497 retval->asoc = (struct sctp_association *) asoc;
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.
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 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
521 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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;
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);
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.]
567 retval->transport = chunk->transport;
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.
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.]
608 retval->transport = chunk->transport;
614 * Appendix A: Explicit Congestion Notification:
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
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;
643 cwr.lowest_tsn = htonl(lowest_tsn);
644 retval = sctp_make_chunk(asoc, SCTP_CID_ECN_CWR, 0,
645 sizeof(sctp_cwrhdr_t));
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
664 retval->transport = chunk->transport;
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;
677 ecne.lowest_tsn = htonl(lowest_tsn);
678 retval = sctp_make_chunk(asoc, SCTP_CID_ECN_ECNE, 0,
679 sizeof(sctp_ecnehdr_t));
682 retval->subh.ecne_hdr =
683 sctp_addto_chunk(retval, sizeof(ecne), &ecne);
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;
700 /* We assign the TSN as LATE as possible, not here when
701 * creating the chunk.
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;
714 chunk_len = sizeof(dp) + data_len;
715 retval = sctp_make_chunk(asoc, SCTP_CID_DATA, flags, chunk_len);
719 retval->subh.data_hdr = sctp_addto_chunk(retval, sizeof(dp), &dp);
720 memcpy(&retval->sinfo, sinfo, sizeof(struct sctp_sndrcvinfo));
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;
736 __u16 num_gabs, num_dup_tsns;
737 struct sctp_association *aptr = (struct sctp_association *)asoc;
738 struct sctp_tsnmap *map = (struct sctp_tsnmap *)&asoc->peer.tsn_map;
739 struct sctp_gap_ack_block gabs[SCTP_MAX_GABS];
740 struct sctp_transport *trans;
742 memset(gabs, 0, sizeof(gabs));
743 ctsn = sctp_tsnmap_get_ctsn(map);
744 SCTP_DEBUG_PRINTK("sackCTSNAck sent: 0x%x.\n", ctsn);
746 /* How much room is needed in the chunk? */
747 num_gabs = sctp_tsnmap_num_gabs(map, gabs);
748 num_dup_tsns = sctp_tsnmap_num_dups(map);
750 /* Initialize the SACK header. */
751 sack.cum_tsn_ack = htonl(ctsn);
752 sack.a_rwnd = htonl(asoc->a_rwnd);
753 sack.num_gap_ack_blocks = htons(num_gabs);
754 sack.num_dup_tsns = htons(num_dup_tsns);
757 + sizeof(struct sctp_gap_ack_block) * num_gabs
758 + sizeof(__u32) * num_dup_tsns;
760 /* Create the chunk. */
761 retval = sctp_make_chunk(asoc, SCTP_CID_SACK, 0, len);
765 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
767 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
768 * HEARTBEAT ACK, etc.) to the same destination transport
769 * address from which it received the DATA or control chunk to
770 * which it is replying. This rule should also be followed if
771 * the endpoint is bundling DATA chunks together with the
774 * However, when acknowledging multiple DATA chunks received
775 * in packets from different source addresses in a single
776 * SACK, the SACK chunk may be transmitted to one of the
777 * destination transport addresses from which the DATA or
778 * control chunks being acknowledged were received.
780 * [BUG: We do not implement the following paragraph.
781 * Perhaps we should remember the last transport we used for a
782 * SACK and avoid that (if possible) if we have seen any
783 * duplicates. --piggy]
785 * When a receiver of a duplicate DATA chunk sends a SACK to a
786 * multi- homed endpoint it MAY be beneficial to vary the
787 * destination address and not use the source address of the
788 * DATA chunk. The reason being that receiving a duplicate
789 * from a multi-homed endpoint might indicate that the return
790 * path (as specified in the source address of the DATA chunk)
791 * for the SACK is broken.
793 * [Send to the address from which we last received a DATA chunk.]
795 retval->transport = asoc->peer.last_data_from;
797 retval->subh.sack_hdr =
798 sctp_addto_chunk(retval, sizeof(sack), &sack);
800 /* Add the gap ack block information. */
802 sctp_addto_chunk(retval, sizeof(__u32) * num_gabs,
805 /* Add the duplicate TSN information. */
807 aptr->stats.idupchunks += num_dup_tsns;
808 sctp_addto_chunk(retval, sizeof(__u32) * num_dup_tsns,
809 sctp_tsnmap_get_dups(map));
811 /* Once we have a sack generated, check to see what our sack
812 * generation is, if its 0, reset the transports to 0, and reset
813 * the association generation to 1
815 * The idea is that zero is never used as a valid generation for the
816 * association so no transport will match after a wrap event like this,
817 * Until the next sack
819 if (++aptr->peer.sack_generation == 0) {
820 list_for_each_entry(trans, &asoc->peer.transport_addr_list,
822 trans->sack_generation = 0;
823 aptr->peer.sack_generation = 1;
829 /* Make a SHUTDOWN chunk. */
830 struct sctp_chunk *sctp_make_shutdown(const struct sctp_association *asoc,
831 const struct sctp_chunk *chunk)
833 struct sctp_chunk *retval;
834 sctp_shutdownhdr_t shut;
837 ctsn = sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map);
838 shut.cum_tsn_ack = htonl(ctsn);
840 retval = sctp_make_chunk(asoc, SCTP_CID_SHUTDOWN, 0,
841 sizeof(sctp_shutdownhdr_t));
845 retval->subh.shutdown_hdr =
846 sctp_addto_chunk(retval, sizeof(shut), &shut);
849 retval->transport = chunk->transport;
854 struct sctp_chunk *sctp_make_shutdown_ack(const struct sctp_association *asoc,
855 const struct sctp_chunk *chunk)
857 struct sctp_chunk *retval;
859 retval = sctp_make_chunk(asoc, SCTP_CID_SHUTDOWN_ACK, 0, 0);
861 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
863 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
864 * HEARTBEAT ACK, * etc.) to the same destination transport
865 * address from which it * received the DATA or control chunk
866 * to which it is replying.
868 * [ACK back to where the SHUTDOWN came from.]
871 retval->transport = chunk->transport;
876 struct sctp_chunk *sctp_make_shutdown_complete(
877 const struct sctp_association *asoc,
878 const struct sctp_chunk *chunk)
880 struct sctp_chunk *retval;
883 /* Set the T-bit if we have no association (vtag will be
886 flags |= asoc ? 0 : SCTP_CHUNK_FLAG_T;
888 retval = sctp_make_chunk(asoc, SCTP_CID_SHUTDOWN_COMPLETE, flags, 0);
890 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
892 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
893 * HEARTBEAT ACK, * etc.) to the same destination transport
894 * address from which it * received the DATA or control chunk
895 * to which it is replying.
897 * [Report SHUTDOWN COMPLETE back to where the SHUTDOWN ACK
901 retval->transport = chunk->transport;
906 /* Create an ABORT. Note that we set the T bit if we have no
907 * association, except when responding to an INIT (sctpimpguide 2.41).
909 struct sctp_chunk *sctp_make_abort(const struct sctp_association *asoc,
910 const struct sctp_chunk *chunk,
913 struct sctp_chunk *retval;
916 /* Set the T-bit if we have no association and 'chunk' is not
917 * an INIT (vtag will be reflected).
920 if (chunk && chunk->chunk_hdr &&
921 chunk->chunk_hdr->type == SCTP_CID_INIT)
924 flags = SCTP_CHUNK_FLAG_T;
927 retval = sctp_make_chunk(asoc, SCTP_CID_ABORT, flags, hint);
929 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
931 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
932 * HEARTBEAT ACK, * etc.) to the same destination transport
933 * address from which it * received the DATA or control chunk
934 * to which it is replying.
936 * [ABORT back to where the offender came from.]
939 retval->transport = chunk->transport;
944 /* Helper to create ABORT with a NO_USER_DATA error. */
945 struct sctp_chunk *sctp_make_abort_no_data(
946 const struct sctp_association *asoc,
947 const struct sctp_chunk *chunk, __u32 tsn)
949 struct sctp_chunk *retval;
952 retval = sctp_make_abort(asoc, chunk, sizeof(sctp_errhdr_t)
958 /* Put the tsn back into network byte order. */
959 payload = htonl(tsn);
960 sctp_init_cause(retval, SCTP_ERROR_NO_DATA, sizeof(payload));
961 sctp_addto_chunk(retval, sizeof(payload), (const void *)&payload);
963 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
965 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
966 * HEARTBEAT ACK, * etc.) to the same destination transport
967 * address from which it * received the DATA or control chunk
968 * to which it is replying.
970 * [ABORT back to where the offender came from.]
973 retval->transport = chunk->transport;
979 /* Helper to create ABORT with a SCTP_ERROR_USER_ABORT error. */
980 struct sctp_chunk *sctp_make_abort_user(const struct sctp_association *asoc,
981 const struct msghdr *msg,
984 struct sctp_chunk *retval;
985 void *payload = NULL;
988 retval = sctp_make_abort(asoc, NULL, sizeof(sctp_errhdr_t) + paylen);
993 /* Put the msg_iov together into payload. */
994 payload = kmalloc(paylen, GFP_KERNEL);
998 err = memcpy_fromiovec(payload, msg->msg_iov, paylen);
1003 sctp_init_cause(retval, SCTP_ERROR_USER_ABORT, paylen);
1004 sctp_addto_chunk(retval, paylen, payload);
1014 sctp_chunk_free(retval);
1020 /* Append bytes to the end of a parameter. Will panic if chunk is not big
1023 static void *sctp_addto_param(struct sctp_chunk *chunk, int len,
1027 int chunklen = ntohs(chunk->chunk_hdr->length);
1029 target = skb_put(chunk->skb, len);
1032 memcpy(target, data, len);
1034 memset(target, 0, len);
1036 /* Adjust the chunk length field. */
1037 chunk->chunk_hdr->length = htons(chunklen + len);
1038 chunk->chunk_end = skb_tail_pointer(chunk->skb);
1043 /* Make an ABORT chunk with a PROTOCOL VIOLATION cause code. */
1044 struct sctp_chunk *sctp_make_abort_violation(
1045 const struct sctp_association *asoc,
1046 const struct sctp_chunk *chunk,
1047 const __u8 *payload,
1048 const size_t paylen)
1050 struct sctp_chunk *retval;
1051 struct sctp_paramhdr phdr;
1053 retval = sctp_make_abort(asoc, chunk, sizeof(sctp_errhdr_t) + paylen
1054 + sizeof(sctp_paramhdr_t));
1058 sctp_init_cause(retval, SCTP_ERROR_PROTO_VIOLATION, paylen
1059 + sizeof(sctp_paramhdr_t));
1061 phdr.type = htons(chunk->chunk_hdr->type);
1062 phdr.length = chunk->chunk_hdr->length;
1063 sctp_addto_chunk(retval, paylen, payload);
1064 sctp_addto_param(retval, sizeof(sctp_paramhdr_t), &phdr);
1070 struct sctp_chunk *sctp_make_violation_paramlen(
1071 const struct sctp_association *asoc,
1072 const struct sctp_chunk *chunk,
1073 struct sctp_paramhdr *param)
1075 struct sctp_chunk *retval;
1076 static const char error[] = "The following parameter had invalid length:";
1077 size_t payload_len = sizeof(error) + sizeof(sctp_errhdr_t) +
1078 sizeof(sctp_paramhdr_t);
1080 retval = sctp_make_abort(asoc, chunk, payload_len);
1084 sctp_init_cause(retval, SCTP_ERROR_PROTO_VIOLATION,
1085 sizeof(error) + sizeof(sctp_paramhdr_t));
1086 sctp_addto_chunk(retval, sizeof(error), error);
1087 sctp_addto_param(retval, sizeof(sctp_paramhdr_t), param);
1093 struct sctp_chunk *sctp_make_violation_max_retrans(
1094 const struct sctp_association *asoc,
1095 const struct sctp_chunk *chunk)
1097 struct sctp_chunk *retval;
1098 static const char error[] = "Association exceeded its max_retans count";
1099 size_t payload_len = sizeof(error) + sizeof(sctp_errhdr_t);
1101 retval = sctp_make_abort(asoc, chunk, payload_len);
1105 sctp_init_cause(retval, SCTP_ERROR_PROTO_VIOLATION, sizeof(error));
1106 sctp_addto_chunk(retval, sizeof(error), error);
1112 /* Make a HEARTBEAT chunk. */
1113 struct sctp_chunk *sctp_make_heartbeat(const struct sctp_association *asoc,
1114 const struct sctp_transport *transport)
1116 struct sctp_chunk *retval;
1117 sctp_sender_hb_info_t hbinfo;
1119 retval = sctp_make_chunk(asoc, SCTP_CID_HEARTBEAT, 0, sizeof(hbinfo));
1124 hbinfo.param_hdr.type = SCTP_PARAM_HEARTBEAT_INFO;
1125 hbinfo.param_hdr.length = htons(sizeof(sctp_sender_hb_info_t));
1126 hbinfo.daddr = transport->ipaddr;
1127 hbinfo.sent_at = jiffies;
1128 hbinfo.hb_nonce = transport->hb_nonce;
1130 /* Cast away the 'const', as this is just telling the chunk
1131 * what transport it belongs to.
1133 retval->transport = (struct sctp_transport *) transport;
1134 retval->subh.hbs_hdr = sctp_addto_chunk(retval, sizeof(hbinfo),
1141 struct sctp_chunk *sctp_make_heartbeat_ack(const struct sctp_association *asoc,
1142 const struct sctp_chunk *chunk,
1143 const void *payload, const size_t paylen)
1145 struct sctp_chunk *retval;
1147 retval = sctp_make_chunk(asoc, SCTP_CID_HEARTBEAT_ACK, 0, paylen);
1151 retval->subh.hbs_hdr = sctp_addto_chunk(retval, paylen, payload);
1153 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
1155 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
1156 * HEARTBEAT ACK, * etc.) to the same destination transport
1157 * address from which it * received the DATA or control chunk
1158 * to which it is replying.
1160 * [HBACK back to where the HEARTBEAT came from.]
1163 retval->transport = chunk->transport;
1169 /* Create an Operation Error chunk with the specified space reserved.
1170 * This routine can be used for containing multiple causes in the chunk.
1172 static struct sctp_chunk *sctp_make_op_error_space(
1173 const struct sctp_association *asoc,
1174 const struct sctp_chunk *chunk,
1177 struct sctp_chunk *retval;
1179 retval = sctp_make_chunk(asoc, SCTP_CID_ERROR, 0,
1180 sizeof(sctp_errhdr_t) + size);
1184 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
1186 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
1187 * HEARTBEAT ACK, etc.) to the same destination transport
1188 * address from which it received the DATA or control chunk
1189 * to which it is replying.
1193 retval->transport = chunk->transport;
1199 /* Create an Operation Error chunk of a fixed size,
1200 * specifically, max(asoc->pathmtu, SCTP_DEFAULT_MAXSEGMENT)
1201 * This is a helper function to allocate an error chunk for
1202 * for those invalid parameter codes in which we may not want
1203 * to report all the errors, if the incoming chunk is large
1205 static inline struct sctp_chunk *sctp_make_op_error_fixed(
1206 const struct sctp_association *asoc,
1207 const struct sctp_chunk *chunk)
1209 size_t size = asoc ? asoc->pathmtu : 0;
1212 size = SCTP_DEFAULT_MAXSEGMENT;
1214 return sctp_make_op_error_space(asoc, chunk, size);
1217 /* Create an Operation Error chunk. */
1218 struct sctp_chunk *sctp_make_op_error(const struct sctp_association *asoc,
1219 const struct sctp_chunk *chunk,
1220 __be16 cause_code, const void *payload,
1221 size_t paylen, size_t reserve_tail)
1223 struct sctp_chunk *retval;
1225 retval = sctp_make_op_error_space(asoc, chunk, paylen + reserve_tail);
1229 sctp_init_cause(retval, cause_code, paylen + reserve_tail);
1230 sctp_addto_chunk(retval, paylen, payload);
1232 sctp_addto_param(retval, reserve_tail, NULL);
1238 struct sctp_chunk *sctp_make_auth(const struct sctp_association *asoc)
1240 struct sctp_chunk *retval;
1241 struct sctp_hmac *hmac_desc;
1242 struct sctp_authhdr auth_hdr;
1245 /* Get the first hmac that the peer told us to use */
1246 hmac_desc = sctp_auth_asoc_get_hmac(asoc);
1247 if (unlikely(!hmac_desc))
1250 retval = sctp_make_chunk(asoc, SCTP_CID_AUTH, 0,
1251 hmac_desc->hmac_len + sizeof(sctp_authhdr_t));
1255 auth_hdr.hmac_id = htons(hmac_desc->hmac_id);
1256 auth_hdr.shkey_id = htons(asoc->active_key_id);
1258 retval->subh.auth_hdr = sctp_addto_chunk(retval, sizeof(sctp_authhdr_t),
1261 hmac = skb_put(retval->skb, hmac_desc->hmac_len);
1262 memset(hmac, 0, hmac_desc->hmac_len);
1264 /* Adjust the chunk header to include the empty MAC */
1265 retval->chunk_hdr->length =
1266 htons(ntohs(retval->chunk_hdr->length) + hmac_desc->hmac_len);
1267 retval->chunk_end = skb_tail_pointer(retval->skb);
1273 /********************************************************************
1274 * 2nd Level Abstractions
1275 ********************************************************************/
1277 /* Turn an skb into a chunk.
1278 * FIXME: Eventually move the structure directly inside the skb->cb[].
1280 struct sctp_chunk *sctp_chunkify(struct sk_buff *skb,
1281 const struct sctp_association *asoc,
1284 struct sctp_chunk *retval;
1286 retval = kmem_cache_zalloc(sctp_chunk_cachep, GFP_ATOMIC);
1292 SCTP_DEBUG_PRINTK("chunkifying skb %p w/o an sk\n", skb);
1295 INIT_LIST_HEAD(&retval->list);
1297 retval->asoc = (struct sctp_association *)asoc;
1298 retval->has_tsn = 0;
1299 retval->has_ssn = 0;
1300 retval->rtt_in_progress = 0;
1301 retval->sent_at = 0;
1302 retval->singleton = 1;
1303 retval->end_of_packet = 0;
1304 retval->ecn_ce_done = 0;
1305 retval->pdiscard = 0;
1307 /* sctpimpguide-05.txt Section 2.8.2
1308 * M1) Each time a new DATA chunk is transmitted
1309 * set the 'TSN.Missing.Report' count for that TSN to 0. The
1310 * 'TSN.Missing.Report' count will be used to determine missing chunks
1311 * and when to fast retransmit.
1313 retval->tsn_missing_report = 0;
1314 retval->tsn_gap_acked = 0;
1315 retval->fast_retransmit = SCTP_CAN_FRTX;
1317 /* If this is a fragmented message, track all fragments
1318 * of the message (for SEND_FAILED).
1322 /* Polish the bead hole. */
1323 INIT_LIST_HEAD(&retval->transmitted_list);
1324 INIT_LIST_HEAD(&retval->frag_list);
1325 SCTP_DBG_OBJCNT_INC(chunk);
1326 atomic_set(&retval->refcnt, 1);
1332 /* Set chunk->source and dest based on the IP header in chunk->skb. */
1333 void sctp_init_addrs(struct sctp_chunk *chunk, union sctp_addr *src,
1334 union sctp_addr *dest)
1336 memcpy(&chunk->source, src, sizeof(union sctp_addr));
1337 memcpy(&chunk->dest, dest, sizeof(union sctp_addr));
1340 /* Extract the source address from a chunk. */
1341 const union sctp_addr *sctp_source(const struct sctp_chunk *chunk)
1343 /* If we have a known transport, use that. */
1344 if (chunk->transport) {
1345 return &chunk->transport->ipaddr;
1347 /* Otherwise, extract it from the IP header. */
1348 return &chunk->source;
1352 /* Create a new chunk, setting the type and flags headers from the
1353 * arguments, reserving enough space for a 'paylen' byte payload.
1355 static struct sctp_chunk *sctp_make_chunk(const struct sctp_association *asoc,
1356 __u8 type, __u8 flags, int paylen)
1358 struct sctp_chunk *retval;
1359 sctp_chunkhdr_t *chunk_hdr;
1360 struct sk_buff *skb;
1363 /* No need to allocate LL here, as this is only a chunk. */
1364 skb = alloc_skb(WORD_ROUND(sizeof(sctp_chunkhdr_t) + paylen),
1369 /* Make room for the chunk header. */
1370 chunk_hdr = (sctp_chunkhdr_t *)skb_put(skb, sizeof(sctp_chunkhdr_t));
1371 chunk_hdr->type = type;
1372 chunk_hdr->flags = flags;
1373 chunk_hdr->length = htons(sizeof(sctp_chunkhdr_t));
1375 sk = asoc ? asoc->base.sk : NULL;
1376 retval = sctp_chunkify(skb, asoc, sk);
1382 retval->chunk_hdr = chunk_hdr;
1383 retval->chunk_end = ((__u8 *)chunk_hdr) + sizeof(struct sctp_chunkhdr);
1385 /* Determine if the chunk needs to be authenticated */
1386 if (sctp_auth_send_cid(type, asoc))
1389 /* Set the skb to the belonging sock for accounting. */
1398 /* Release the memory occupied by a chunk. */
1399 static void sctp_chunk_destroy(struct sctp_chunk *chunk)
1401 BUG_ON(!list_empty(&chunk->list));
1402 list_del_init(&chunk->transmitted_list);
1404 /* Free the chunk skb data and the SCTP_chunk stub itself. */
1405 dev_kfree_skb(chunk->skb);
1407 SCTP_DBG_OBJCNT_DEC(chunk);
1408 kmem_cache_free(sctp_chunk_cachep, chunk);
1411 /* Possibly, free the chunk. */
1412 void sctp_chunk_free(struct sctp_chunk *chunk)
1414 /* Release our reference on the message tracker. */
1416 sctp_datamsg_put(chunk->msg);
1418 sctp_chunk_put(chunk);
1421 /* Grab a reference to the chunk. */
1422 void sctp_chunk_hold(struct sctp_chunk *ch)
1424 atomic_inc(&ch->refcnt);
1427 /* Release a reference to the chunk. */
1428 void sctp_chunk_put(struct sctp_chunk *ch)
1430 if (atomic_dec_and_test(&ch->refcnt))
1431 sctp_chunk_destroy(ch);
1434 /* Append bytes to the end of a chunk. Will panic if chunk is not big
1437 void *sctp_addto_chunk(struct sctp_chunk *chunk, int len, const void *data)
1441 int chunklen = ntohs(chunk->chunk_hdr->length);
1442 int padlen = WORD_ROUND(chunklen) - chunklen;
1444 padding = skb_put(chunk->skb, padlen);
1445 target = skb_put(chunk->skb, len);
1447 memset(padding, 0, padlen);
1448 memcpy(target, data, len);
1450 /* Adjust the chunk length field. */
1451 chunk->chunk_hdr->length = htons(chunklen + padlen + len);
1452 chunk->chunk_end = skb_tail_pointer(chunk->skb);
1457 /* Append bytes to the end of a chunk. Returns NULL if there isn't sufficient
1458 * space in the chunk
1460 void *sctp_addto_chunk_fixed(struct sctp_chunk *chunk,
1461 int len, const void *data)
1463 if (skb_tailroom(chunk->skb) >= len)
1464 return sctp_addto_chunk(chunk, len, data);
1469 /* Append bytes from user space to the end of a chunk. Will panic if
1470 * chunk is not big enough.
1471 * Returns a kernel err value.
1473 int sctp_user_addto_chunk(struct sctp_chunk *chunk, int off, int len,
1479 /* Make room in chunk for data. */
1480 target = skb_put(chunk->skb, len);
1482 /* Copy data (whole iovec) into chunk */
1483 if ((err = memcpy_fromiovecend(target, data, off, len)))
1486 /* Adjust the chunk length field. */
1487 chunk->chunk_hdr->length =
1488 htons(ntohs(chunk->chunk_hdr->length) + len);
1489 chunk->chunk_end = skb_tail_pointer(chunk->skb);
1495 /* Helper function to assign a TSN if needed. This assumes that both
1496 * the data_hdr and association have already been assigned.
1498 void sctp_chunk_assign_ssn(struct sctp_chunk *chunk)
1500 struct sctp_datamsg *msg;
1501 struct sctp_chunk *lchunk;
1502 struct sctp_stream *stream;
1509 /* All fragments will be on the same stream */
1510 sid = ntohs(chunk->subh.data_hdr->stream);
1511 stream = &chunk->asoc->ssnmap->out;
1513 /* Now assign the sequence number to the entire message.
1514 * All fragments must have the same stream sequence number.
1517 list_for_each_entry(lchunk, &msg->chunks, frag_list) {
1518 if (lchunk->chunk_hdr->flags & SCTP_DATA_UNORDERED) {
1521 if (lchunk->chunk_hdr->flags & SCTP_DATA_LAST_FRAG)
1522 ssn = sctp_ssn_next(stream, sid);
1524 ssn = sctp_ssn_peek(stream, sid);
1527 lchunk->subh.data_hdr->ssn = htons(ssn);
1528 lchunk->has_ssn = 1;
1532 /* Helper function to assign a TSN if needed. This assumes that both
1533 * the data_hdr and association have already been assigned.
1535 void sctp_chunk_assign_tsn(struct sctp_chunk *chunk)
1537 if (!chunk->has_tsn) {
1538 /* This is the last possible instant to
1541 chunk->subh.data_hdr->tsn =
1542 htonl(sctp_association_get_next_tsn(chunk->asoc));
1547 /* Create a CLOSED association to use with an incoming packet. */
1548 struct sctp_association *sctp_make_temp_asoc(const struct sctp_endpoint *ep,
1549 struct sctp_chunk *chunk,
1552 struct sctp_association *asoc;
1553 struct sk_buff *skb;
1557 /* Create the bare association. */
1558 scope = sctp_scope(sctp_source(chunk));
1559 asoc = sctp_association_new(ep, ep->base.sk, scope, gfp);
1564 /* Create an entry for the source address of the packet. */
1565 af = sctp_get_af_specific(ipver2af(ip_hdr(skb)->version));
1568 af->from_skb(&asoc->c.peer_addr, skb, 1);
1573 sctp_association_free(asoc);
1577 /* Build a cookie representing asoc.
1578 * This INCLUDES the param header needed to put the cookie in the INIT ACK.
1580 static sctp_cookie_param_t *sctp_pack_cookie(const struct sctp_endpoint *ep,
1581 const struct sctp_association *asoc,
1582 const struct sctp_chunk *init_chunk,
1584 const __u8 *raw_addrs, int addrs_len)
1586 sctp_cookie_param_t *retval;
1587 struct sctp_signed_cookie *cookie;
1588 struct scatterlist sg;
1589 int headersize, bodysize;
1591 /* Header size is static data prior to the actual cookie, including
1594 headersize = sizeof(sctp_paramhdr_t) +
1595 (sizeof(struct sctp_signed_cookie) -
1596 sizeof(struct sctp_cookie));
1597 bodysize = sizeof(struct sctp_cookie)
1598 + ntohs(init_chunk->chunk_hdr->length) + addrs_len;
1600 /* Pad out the cookie to a multiple to make the signature
1601 * functions simpler to write.
1603 if (bodysize % SCTP_COOKIE_MULTIPLE)
1604 bodysize += SCTP_COOKIE_MULTIPLE
1605 - (bodysize % SCTP_COOKIE_MULTIPLE);
1606 *cookie_len = headersize + bodysize;
1608 /* Clear this memory since we are sending this data structure
1609 * out on the network.
1611 retval = kzalloc(*cookie_len, GFP_ATOMIC);
1615 cookie = (struct sctp_signed_cookie *) retval->body;
1617 /* Set up the parameter header. */
1618 retval->p.type = SCTP_PARAM_STATE_COOKIE;
1619 retval->p.length = htons(*cookie_len);
1621 /* Copy the cookie part of the association itself. */
1622 cookie->c = asoc->c;
1623 /* Save the raw address list length in the cookie. */
1624 cookie->c.raw_addr_list_len = addrs_len;
1626 /* Remember PR-SCTP capability. */
1627 cookie->c.prsctp_capable = asoc->peer.prsctp_capable;
1629 /* Save adaptation indication in the cookie. */
1630 cookie->c.adaptation_ind = asoc->peer.adaptation_ind;
1632 /* Set an expiration time for the cookie. */
1633 do_gettimeofday(&cookie->c.expiration);
1634 TIMEVAL_ADD(asoc->cookie_life, cookie->c.expiration);
1636 /* Copy the peer's init packet. */
1637 memcpy(&cookie->c.peer_init[0], init_chunk->chunk_hdr,
1638 ntohs(init_chunk->chunk_hdr->length));
1640 /* Copy the raw local address list of the association. */
1641 memcpy((__u8 *)&cookie->c.peer_init[0] +
1642 ntohs(init_chunk->chunk_hdr->length), raw_addrs, addrs_len);
1644 if (sctp_sk(ep->base.sk)->hmac) {
1645 struct hash_desc desc;
1647 /* Sign the message. */
1648 sg_init_one(&sg, &cookie->c, bodysize);
1649 desc.tfm = sctp_sk(ep->base.sk)->hmac;
1652 if (crypto_hash_setkey(desc.tfm, ep->secret_key,
1653 sizeof(ep->secret_key)) ||
1654 crypto_hash_digest(&desc, &sg, bodysize, cookie->signature))
1667 /* Unpack the cookie from COOKIE ECHO chunk, recreating the association. */
1668 struct sctp_association *sctp_unpack_cookie(
1669 const struct sctp_endpoint *ep,
1670 const struct sctp_association *asoc,
1671 struct sctp_chunk *chunk, gfp_t gfp,
1672 int *error, struct sctp_chunk **errp)
1674 struct sctp_association *retval = NULL;
1675 struct sctp_signed_cookie *cookie;
1676 struct sctp_cookie *bear_cookie;
1677 int headersize, bodysize, fixed_size;
1678 __u8 *digest = ep->digest;
1679 struct scatterlist sg;
1682 struct sk_buff *skb = chunk->skb;
1684 struct hash_desc desc;
1686 /* Header size is static data prior to the actual cookie, including
1689 headersize = sizeof(sctp_chunkhdr_t) +
1690 (sizeof(struct sctp_signed_cookie) -
1691 sizeof(struct sctp_cookie));
1692 bodysize = ntohs(chunk->chunk_hdr->length) - headersize;
1693 fixed_size = headersize + sizeof(struct sctp_cookie);
1695 /* Verify that the chunk looks like it even has a cookie.
1696 * There must be enough room for our cookie and our peer's
1699 len = ntohs(chunk->chunk_hdr->length);
1700 if (len < fixed_size + sizeof(struct sctp_chunkhdr))
1703 /* Verify that the cookie has been padded out. */
1704 if (bodysize % SCTP_COOKIE_MULTIPLE)
1707 /* Process the cookie. */
1708 cookie = chunk->subh.cookie_hdr;
1709 bear_cookie = &cookie->c;
1711 if (!sctp_sk(ep->base.sk)->hmac)
1714 /* Check the signature. */
1715 sg_init_one(&sg, bear_cookie, bodysize);
1716 desc.tfm = sctp_sk(ep->base.sk)->hmac;
1719 memset(digest, 0x00, SCTP_SIGNATURE_SIZE);
1720 if (crypto_hash_setkey(desc.tfm, ep->secret_key,
1721 sizeof(ep->secret_key)) ||
1722 crypto_hash_digest(&desc, &sg, bodysize, digest)) {
1723 *error = -SCTP_IERROR_NOMEM;
1727 if (memcmp(digest, cookie->signature, SCTP_SIGNATURE_SIZE)) {
1728 *error = -SCTP_IERROR_BAD_SIG;
1733 /* IG Section 2.35.2:
1734 * 3) Compare the port numbers and the verification tag contained
1735 * within the COOKIE ECHO chunk to the actual port numbers and the
1736 * verification tag within the SCTP common header of the received
1737 * packet. If these values do not match the packet MUST be silently
1740 if (ntohl(chunk->sctp_hdr->vtag) != bear_cookie->my_vtag) {
1741 *error = -SCTP_IERROR_BAD_TAG;
1745 if (chunk->sctp_hdr->source != bear_cookie->peer_addr.v4.sin_port ||
1746 ntohs(chunk->sctp_hdr->dest) != bear_cookie->my_port) {
1747 *error = -SCTP_IERROR_BAD_PORTS;
1751 /* Check to see if the cookie is stale. If there is already
1752 * an association, there is no need to check cookie's expiration
1753 * for init collision case of lost COOKIE ACK.
1754 * If skb has been timestamped, then use the stamp, otherwise
1755 * use current time. This introduces a small possibility that
1756 * that a cookie may be considered expired, but his would only slow
1757 * down the new association establishment instead of every packet.
1759 if (sock_flag(ep->base.sk, SOCK_TIMESTAMP))
1760 skb_get_timestamp(skb, &tv);
1762 do_gettimeofday(&tv);
1764 if (!asoc && tv_lt(bear_cookie->expiration, tv)) {
1766 * Section 3.3.10.3 Stale Cookie Error (3)
1770 * Stale Cookie Error: Indicates the receipt of a valid State
1771 * Cookie that has expired.
1773 len = ntohs(chunk->chunk_hdr->length);
1774 *errp = sctp_make_op_error_space(asoc, chunk, len);
1776 suseconds_t usecs = (tv.tv_sec -
1777 bear_cookie->expiration.tv_sec) * 1000000L +
1778 tv.tv_usec - bear_cookie->expiration.tv_usec;
1779 __be32 n = htonl(usecs);
1781 sctp_init_cause(*errp, SCTP_ERROR_STALE_COOKIE,
1783 sctp_addto_chunk(*errp, sizeof(n), &n);
1784 *error = -SCTP_IERROR_STALE_COOKIE;
1786 *error = -SCTP_IERROR_NOMEM;
1791 /* Make a new base association. */
1792 scope = sctp_scope(sctp_source(chunk));
1793 retval = sctp_association_new(ep, ep->base.sk, scope, gfp);
1795 *error = -SCTP_IERROR_NOMEM;
1799 /* Set up our peer's port number. */
1800 retval->peer.port = ntohs(chunk->sctp_hdr->source);
1802 /* Populate the association from the cookie. */
1803 memcpy(&retval->c, bear_cookie, sizeof(*bear_cookie));
1805 if (sctp_assoc_set_bind_addr_from_cookie(retval, bear_cookie,
1807 *error = -SCTP_IERROR_NOMEM;
1811 /* Also, add the destination address. */
1812 if (list_empty(&retval->base.bind_addr.address_list)) {
1813 sctp_add_bind_addr(&retval->base.bind_addr, &chunk->dest,
1814 SCTP_ADDR_SRC, GFP_ATOMIC);
1817 retval->next_tsn = retval->c.initial_tsn;
1818 retval->ctsn_ack_point = retval->next_tsn - 1;
1819 retval->addip_serial = retval->c.initial_tsn;
1820 retval->adv_peer_ack_point = retval->ctsn_ack_point;
1821 retval->peer.prsctp_capable = retval->c.prsctp_capable;
1822 retval->peer.adaptation_ind = retval->c.adaptation_ind;
1824 /* The INIT stuff will be done by the side effects. */
1829 sctp_association_free(retval);
1834 /* Yikes! The packet is either corrupt or deliberately
1837 *error = -SCTP_IERROR_MALFORMED;
1841 /********************************************************************
1842 * 3rd Level Abstractions
1843 ********************************************************************/
1845 struct __sctp_missing {
1851 * Report a missing mandatory parameter.
1853 static int sctp_process_missing_param(const struct sctp_association *asoc,
1854 sctp_param_t paramtype,
1855 struct sctp_chunk *chunk,
1856 struct sctp_chunk **errp)
1858 struct __sctp_missing report;
1861 len = WORD_ROUND(sizeof(report));
1863 /* Make an ERROR chunk, preparing enough room for
1864 * returning multiple unknown parameters.
1867 *errp = sctp_make_op_error_space(asoc, chunk, len);
1870 report.num_missing = htonl(1);
1871 report.type = paramtype;
1872 sctp_init_cause(*errp, SCTP_ERROR_MISS_PARAM,
1874 sctp_addto_chunk(*errp, sizeof(report), &report);
1877 /* Stop processing this chunk. */
1881 /* Report an Invalid Mandatory Parameter. */
1882 static int sctp_process_inv_mandatory(const struct sctp_association *asoc,
1883 struct sctp_chunk *chunk,
1884 struct sctp_chunk **errp)
1886 /* Invalid Mandatory Parameter Error has no payload. */
1889 *errp = sctp_make_op_error_space(asoc, chunk, 0);
1892 sctp_init_cause(*errp, SCTP_ERROR_INV_PARAM, 0);
1894 /* Stop processing this chunk. */
1898 static int sctp_process_inv_paramlength(const struct sctp_association *asoc,
1899 struct sctp_paramhdr *param,
1900 const struct sctp_chunk *chunk,
1901 struct sctp_chunk **errp)
1903 /* This is a fatal error. Any accumulated non-fatal errors are
1907 sctp_chunk_free(*errp);
1909 /* Create an error chunk and fill it in with our payload. */
1910 *errp = sctp_make_violation_paramlen(asoc, chunk, param);
1916 /* Do not attempt to handle the HOST_NAME parm. However, do
1917 * send back an indicator to the peer.
1919 static int sctp_process_hn_param(const struct sctp_association *asoc,
1920 union sctp_params param,
1921 struct sctp_chunk *chunk,
1922 struct sctp_chunk **errp)
1924 __u16 len = ntohs(param.p->length);
1926 /* Processing of the HOST_NAME parameter will generate an
1927 * ABORT. If we've accumulated any non-fatal errors, they
1928 * would be unrecognized parameters and we should not include
1929 * them in the ABORT.
1932 sctp_chunk_free(*errp);
1934 *errp = sctp_make_op_error_space(asoc, chunk, len);
1937 sctp_init_cause(*errp, SCTP_ERROR_DNS_FAILED, len);
1938 sctp_addto_chunk(*errp, len, param.v);
1941 /* Stop processing this chunk. */
1945 static int sctp_verify_ext_param(struct net *net, union sctp_params param)
1947 __u16 num_ext = ntohs(param.p->length) - sizeof(sctp_paramhdr_t);
1949 int have_asconf = 0;
1952 for (i = 0; i < num_ext; i++) {
1953 switch (param.ext->chunks[i]) {
1957 case SCTP_CID_ASCONF:
1958 case SCTP_CID_ASCONF_ACK:
1964 /* ADD-IP Security: The draft requires us to ABORT or ignore the
1965 * INIT/INIT-ACK if ADD-IP is listed, but AUTH is not. Do this
1966 * only if ADD-IP is turned on and we are not backward-compatible
1969 if (net->sctp.addip_noauth)
1972 if (net->sctp.addip_enable && !have_auth && have_asconf)
1978 static void sctp_process_ext_param(struct sctp_association *asoc,
1979 union sctp_params param)
1981 struct net *net = sock_net(asoc->base.sk);
1982 __u16 num_ext = ntohs(param.p->length) - sizeof(sctp_paramhdr_t);
1985 for (i = 0; i < num_ext; i++) {
1986 switch (param.ext->chunks[i]) {
1987 case SCTP_CID_FWD_TSN:
1988 if (net->sctp.prsctp_enable &&
1989 !asoc->peer.prsctp_capable)
1990 asoc->peer.prsctp_capable = 1;
1993 /* if the peer reports AUTH, assume that he
1996 if (net->sctp.auth_enable)
1997 asoc->peer.auth_capable = 1;
1999 case SCTP_CID_ASCONF:
2000 case SCTP_CID_ASCONF_ACK:
2001 if (net->sctp.addip_enable)
2002 asoc->peer.asconf_capable = 1;
2010 /* RFC 3.2.1 & the Implementers Guide 2.2.
2012 * The Parameter Types are encoded such that the
2013 * highest-order two bits specify the action that must be
2014 * taken if the processing endpoint does not recognize the
2017 * 00 - Stop processing this parameter; do not process any further
2018 * parameters within this chunk
2020 * 01 - Stop processing this parameter, do not process any further
2021 * parameters within this chunk, and report the unrecognized
2022 * parameter in an 'Unrecognized Parameter' ERROR chunk.
2024 * 10 - Skip this parameter and continue processing.
2026 * 11 - Skip this parameter and continue processing but
2027 * report the unrecognized parameter in an
2028 * 'Unrecognized Parameter' ERROR chunk.
2031 * SCTP_IERROR_NO_ERROR - continue with the chunk
2032 * SCTP_IERROR_ERROR - stop and report an error.
2033 * SCTP_IERROR_NOMEME - out of memory.
2035 static sctp_ierror_t sctp_process_unk_param(const struct sctp_association *asoc,
2036 union sctp_params param,
2037 struct sctp_chunk *chunk,
2038 struct sctp_chunk **errp)
2040 int retval = SCTP_IERROR_NO_ERROR;
2042 switch (param.p->type & SCTP_PARAM_ACTION_MASK) {
2043 case SCTP_PARAM_ACTION_DISCARD:
2044 retval = SCTP_IERROR_ERROR;
2046 case SCTP_PARAM_ACTION_SKIP:
2048 case SCTP_PARAM_ACTION_DISCARD_ERR:
2049 retval = SCTP_IERROR_ERROR;
2051 case SCTP_PARAM_ACTION_SKIP_ERR:
2052 /* Make an ERROR chunk, preparing enough room for
2053 * returning multiple unknown parameters.
2056 *errp = sctp_make_op_error_fixed(asoc, chunk);
2059 if (!sctp_init_cause_fixed(*errp, SCTP_ERROR_UNKNOWN_PARAM,
2060 WORD_ROUND(ntohs(param.p->length))))
2061 sctp_addto_chunk_fixed(*errp,
2062 WORD_ROUND(ntohs(param.p->length)),
2065 /* If there is no memory for generating the ERROR
2066 * report as specified, an ABORT will be triggered
2067 * to the peer and the association won't be
2070 retval = SCTP_IERROR_NOMEM;
2080 /* Verify variable length parameters
2082 * SCTP_IERROR_ABORT - trigger an ABORT
2083 * SCTP_IERROR_NOMEM - out of memory (abort)
2084 * SCTP_IERROR_ERROR - stop processing, trigger an ERROR
2085 * SCTP_IERROR_NO_ERROR - continue with the chunk
2087 static sctp_ierror_t sctp_verify_param(struct net *net,
2088 const struct sctp_association *asoc,
2089 union sctp_params param,
2091 struct sctp_chunk *chunk,
2092 struct sctp_chunk **err_chunk)
2094 struct sctp_hmac_algo_param *hmacs;
2095 int retval = SCTP_IERROR_NO_ERROR;
2096 __u16 n_elt, id = 0;
2099 /* FIXME - This routine is not looking at each parameter per the
2100 * chunk type, i.e., unrecognized parameters should be further
2101 * identified based on the chunk id.
2104 switch (param.p->type) {
2105 case SCTP_PARAM_IPV4_ADDRESS:
2106 case SCTP_PARAM_IPV6_ADDRESS:
2107 case SCTP_PARAM_COOKIE_PRESERVATIVE:
2108 case SCTP_PARAM_SUPPORTED_ADDRESS_TYPES:
2109 case SCTP_PARAM_STATE_COOKIE:
2110 case SCTP_PARAM_HEARTBEAT_INFO:
2111 case SCTP_PARAM_UNRECOGNIZED_PARAMETERS:
2112 case SCTP_PARAM_ECN_CAPABLE:
2113 case SCTP_PARAM_ADAPTATION_LAYER_IND:
2116 case SCTP_PARAM_SUPPORTED_EXT:
2117 if (!sctp_verify_ext_param(net, param))
2118 return SCTP_IERROR_ABORT;
2121 case SCTP_PARAM_SET_PRIMARY:
2122 if (net->sctp.addip_enable)
2126 case SCTP_PARAM_HOST_NAME_ADDRESS:
2127 /* Tell the peer, we won't support this param. */
2128 sctp_process_hn_param(asoc, param, chunk, err_chunk);
2129 retval = SCTP_IERROR_ABORT;
2132 case SCTP_PARAM_FWD_TSN_SUPPORT:
2133 if (net->sctp.prsctp_enable)
2137 case SCTP_PARAM_RANDOM:
2138 if (!net->sctp.auth_enable)
2141 /* SCTP-AUTH: Secion 6.1
2142 * If the random number is not 32 byte long the association
2143 * MUST be aborted. The ABORT chunk SHOULD contain the error
2144 * cause 'Protocol Violation'.
2146 if (SCTP_AUTH_RANDOM_LENGTH !=
2147 ntohs(param.p->length) - sizeof(sctp_paramhdr_t)) {
2148 sctp_process_inv_paramlength(asoc, param.p,
2150 retval = SCTP_IERROR_ABORT;
2154 case SCTP_PARAM_CHUNKS:
2155 if (!net->sctp.auth_enable)
2158 /* SCTP-AUTH: Section 3.2
2159 * The CHUNKS parameter MUST be included once in the INIT or
2160 * INIT-ACK chunk if the sender wants to receive authenticated
2161 * chunks. Its maximum length is 260 bytes.
2163 if (260 < ntohs(param.p->length)) {
2164 sctp_process_inv_paramlength(asoc, param.p,
2166 retval = SCTP_IERROR_ABORT;
2170 case SCTP_PARAM_HMAC_ALGO:
2171 if (!net->sctp.auth_enable)
2174 hmacs = (struct sctp_hmac_algo_param *)param.p;
2175 n_elt = (ntohs(param.p->length) - sizeof(sctp_paramhdr_t)) >> 1;
2177 /* SCTP-AUTH: Section 6.1
2178 * The HMAC algorithm based on SHA-1 MUST be supported and
2179 * included in the HMAC-ALGO parameter.
2181 for (i = 0; i < n_elt; i++) {
2182 id = ntohs(hmacs->hmac_ids[i]);
2184 if (id == SCTP_AUTH_HMAC_ID_SHA1)
2188 if (id != SCTP_AUTH_HMAC_ID_SHA1) {
2189 sctp_process_inv_paramlength(asoc, param.p, chunk,
2191 retval = SCTP_IERROR_ABORT;
2196 SCTP_DEBUG_PRINTK("Unrecognized param: %d for chunk %d.\n",
2197 ntohs(param.p->type), cid);
2198 retval = sctp_process_unk_param(asoc, param, chunk, err_chunk);
2204 /* Verify the INIT packet before we process it. */
2205 int sctp_verify_init(struct net *net, const struct sctp_association *asoc,
2207 sctp_init_chunk_t *peer_init,
2208 struct sctp_chunk *chunk,
2209 struct sctp_chunk **errp)
2211 union sctp_params param;
2215 /* Verify stream values are non-zero. */
2216 if ((0 == peer_init->init_hdr.num_outbound_streams) ||
2217 (0 == peer_init->init_hdr.num_inbound_streams) ||
2218 (0 == peer_init->init_hdr.init_tag) ||
2219 (SCTP_DEFAULT_MINWINDOW > ntohl(peer_init->init_hdr.a_rwnd))) {
2221 return sctp_process_inv_mandatory(asoc, chunk, errp);
2224 /* Check for missing mandatory parameters. */
2225 sctp_walk_params(param, peer_init, init_hdr.params) {
2227 if (SCTP_PARAM_STATE_COOKIE == param.p->type)
2230 } /* for (loop through all parameters) */
2232 /* There is a possibility that a parameter length was bad and
2233 * in that case we would have stoped walking the parameters.
2234 * The current param.p would point at the bad one.
2235 * Current consensus on the mailing list is to generate a PROTOCOL
2236 * VIOLATION error. We build the ERROR chunk here and let the normal
2237 * error handling code build and send the packet.
2239 if (param.v != (void*)chunk->chunk_end)
2240 return sctp_process_inv_paramlength(asoc, param.p, chunk, errp);
2242 /* The only missing mandatory param possible today is
2243 * the state cookie for an INIT-ACK chunk.
2245 if ((SCTP_CID_INIT_ACK == cid) && !has_cookie)
2246 return sctp_process_missing_param(asoc, SCTP_PARAM_STATE_COOKIE,
2249 /* Verify all the variable length parameters */
2250 sctp_walk_params(param, peer_init, init_hdr.params) {
2252 result = sctp_verify_param(net, asoc, param, cid, chunk, errp);
2254 case SCTP_IERROR_ABORT:
2255 case SCTP_IERROR_NOMEM:
2257 case SCTP_IERROR_ERROR:
2259 case SCTP_IERROR_NO_ERROR:
2264 } /* for (loop through all parameters) */
2269 /* Unpack the parameters in an INIT packet into an association.
2270 * Returns 0 on failure, else success.
2271 * FIXME: This is an association method.
2273 int sctp_process_init(struct sctp_association *asoc, struct sctp_chunk *chunk,
2274 const union sctp_addr *peer_addr,
2275 sctp_init_chunk_t *peer_init, gfp_t gfp)
2277 struct net *net = sock_net(asoc->base.sk);
2278 union sctp_params param;
2279 struct sctp_transport *transport;
2280 struct list_head *pos, *temp;
2282 union sctp_addr addr;
2286 /* We must include the address that the INIT packet came from.
2287 * This is the only address that matters for an INIT packet.
2288 * When processing a COOKIE ECHO, we retrieve the from address
2289 * of the INIT from the cookie.
2292 /* This implementation defaults to making the first transport
2293 * added as the primary transport. The source address seems to
2294 * be a a better choice than any of the embedded addresses.
2296 if(!sctp_assoc_add_peer(asoc, peer_addr, gfp, SCTP_ACTIVE))
2299 if (sctp_cmp_addr_exact(sctp_source(chunk), peer_addr))
2302 /* Process the initialization parameters. */
2303 sctp_walk_params(param, peer_init, init_hdr.params) {
2304 if (!src_match && (param.p->type == SCTP_PARAM_IPV4_ADDRESS ||
2305 param.p->type == SCTP_PARAM_IPV6_ADDRESS)) {
2306 af = sctp_get_af_specific(param_type2af(param.p->type));
2307 af->from_addr_param(&addr, param.addr,
2308 chunk->sctp_hdr->source, 0);
2309 if (sctp_cmp_addr_exact(sctp_source(chunk), &addr))
2313 if (!sctp_process_param(asoc, param, peer_addr, gfp))
2317 /* source address of chunk may not match any valid address */
2321 /* AUTH: After processing the parameters, make sure that we
2322 * have all the required info to potentially do authentications.
2324 if (asoc->peer.auth_capable && (!asoc->peer.peer_random ||
2325 !asoc->peer.peer_hmacs))
2326 asoc->peer.auth_capable = 0;
2328 /* In a non-backward compatible mode, if the peer claims
2329 * support for ADD-IP but not AUTH, the ADD-IP spec states
2330 * that we MUST ABORT the association. Section 6. The section
2331 * also give us an option to silently ignore the packet, which
2332 * is what we'll do here.
2334 if (!net->sctp.addip_noauth &&
2335 (asoc->peer.asconf_capable && !asoc->peer.auth_capable)) {
2336 asoc->peer.addip_disabled_mask |= (SCTP_PARAM_ADD_IP |
2338 SCTP_PARAM_SET_PRIMARY);
2339 asoc->peer.asconf_capable = 0;
2343 /* Walk list of transports, removing transports in the UNKNOWN state. */
2344 list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
2345 transport = list_entry(pos, struct sctp_transport, transports);
2346 if (transport->state == SCTP_UNKNOWN) {
2347 sctp_assoc_rm_peer(asoc, transport);
2351 /* The fixed INIT headers are always in network byte
2354 asoc->peer.i.init_tag =
2355 ntohl(peer_init->init_hdr.init_tag);
2356 asoc->peer.i.a_rwnd =
2357 ntohl(peer_init->init_hdr.a_rwnd);
2358 asoc->peer.i.num_outbound_streams =
2359 ntohs(peer_init->init_hdr.num_outbound_streams);
2360 asoc->peer.i.num_inbound_streams =
2361 ntohs(peer_init->init_hdr.num_inbound_streams);
2362 asoc->peer.i.initial_tsn =
2363 ntohl(peer_init->init_hdr.initial_tsn);
2365 /* Apply the upper bounds for output streams based on peer's
2366 * number of inbound streams.
2368 if (asoc->c.sinit_num_ostreams >
2369 ntohs(peer_init->init_hdr.num_inbound_streams)) {
2370 asoc->c.sinit_num_ostreams =
2371 ntohs(peer_init->init_hdr.num_inbound_streams);
2374 if (asoc->c.sinit_max_instreams >
2375 ntohs(peer_init->init_hdr.num_outbound_streams)) {
2376 asoc->c.sinit_max_instreams =
2377 ntohs(peer_init->init_hdr.num_outbound_streams);
2380 /* Copy Initiation tag from INIT to VT_peer in cookie. */
2381 asoc->c.peer_vtag = asoc->peer.i.init_tag;
2383 /* Peer Rwnd : Current calculated value of the peer's rwnd. */
2384 asoc->peer.rwnd = asoc->peer.i.a_rwnd;
2386 /* Copy cookie in case we need to resend COOKIE-ECHO. */
2387 cookie = asoc->peer.cookie;
2389 asoc->peer.cookie = kmemdup(cookie, asoc->peer.cookie_len, gfp);
2390 if (!asoc->peer.cookie)
2394 /* RFC 2960 7.2.1 The initial value of ssthresh MAY be arbitrarily
2395 * high (for example, implementations MAY use the size of the receiver
2396 * advertised window).
2398 list_for_each_entry(transport, &asoc->peer.transport_addr_list,
2400 transport->ssthresh = asoc->peer.i.a_rwnd;
2403 /* Set up the TSN tracking pieces. */
2404 if (!sctp_tsnmap_init(&asoc->peer.tsn_map, SCTP_TSN_MAP_INITIAL,
2405 asoc->peer.i.initial_tsn, gfp))
2408 /* RFC 2960 6.5 Stream Identifier and Stream Sequence Number
2410 * The stream sequence number in all the streams shall start
2411 * from 0 when the association is established. Also, when the
2412 * stream sequence number reaches the value 65535 the next
2413 * stream sequence number shall be set to 0.
2416 /* Allocate storage for the negotiated streams if it is not a temporary
2422 asoc->ssnmap = sctp_ssnmap_new(asoc->c.sinit_max_instreams,
2423 asoc->c.sinit_num_ostreams, gfp);
2427 error = sctp_assoc_set_id(asoc, gfp);
2432 /* ADDIP Section 4.1 ASCONF Chunk Procedures
2434 * When an endpoint has an ASCONF signaled change to be sent to the
2435 * remote endpoint it should do the following:
2437 * A2) A serial number should be assigned to the Chunk. The serial
2438 * number should be a monotonically increasing number. All serial
2439 * numbers are defined to be initialized at the start of the
2440 * association to the same value as the Initial TSN.
2442 asoc->peer.addip_serial = asoc->peer.i.initial_tsn - 1;
2446 /* Release the transport structures. */
2447 list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
2448 transport = list_entry(pos, struct sctp_transport, transports);
2449 if (transport->state != SCTP_ACTIVE)
2450 sctp_assoc_rm_peer(asoc, transport);
2458 /* Update asoc with the option described in param.
2460 * RFC2960 3.3.2.1 Optional/Variable Length Parameters in INIT
2462 * asoc is the association to update.
2463 * param is the variable length parameter to use for update.
2464 * cid tells us if this is an INIT, INIT ACK or COOKIE ECHO.
2465 * If the current packet is an INIT we want to minimize the amount of
2466 * work we do. In particular, we should not build transport
2467 * structures for the addresses.
2469 static int sctp_process_param(struct sctp_association *asoc,
2470 union sctp_params param,
2471 const union sctp_addr *peer_addr,
2474 struct net *net = sock_net(asoc->base.sk);
2475 union sctp_addr addr;
2482 union sctp_addr_param *addr_param;
2483 struct sctp_transport *t;
2485 /* We maintain all INIT parameters in network byte order all the
2486 * time. This allows us to not worry about whether the parameters
2487 * came from a fresh INIT, and INIT ACK, or were stored in a cookie.
2489 switch (param.p->type) {
2490 case SCTP_PARAM_IPV6_ADDRESS:
2491 if (PF_INET6 != asoc->base.sk->sk_family)
2495 case SCTP_PARAM_IPV4_ADDRESS:
2496 /* v4 addresses are not allowed on v6-only socket */
2497 if (ipv6_only_sock(asoc->base.sk))
2500 af = sctp_get_af_specific(param_type2af(param.p->type));
2501 af->from_addr_param(&addr, param.addr, htons(asoc->peer.port), 0);
2502 scope = sctp_scope(peer_addr);
2503 if (sctp_in_scope(net, &addr, scope))
2504 if (!sctp_assoc_add_peer(asoc, &addr, gfp, SCTP_UNCONFIRMED))
2508 case SCTP_PARAM_COOKIE_PRESERVATIVE:
2509 if (!net->sctp.cookie_preserve_enable)
2512 stale = ntohl(param.life->lifespan_increment);
2514 /* Suggested Cookie Life span increment's unit is msec,
2517 asoc->cookie_life.tv_sec += stale / 1000;
2518 asoc->cookie_life.tv_usec += (stale % 1000) * 1000;
2521 case SCTP_PARAM_HOST_NAME_ADDRESS:
2522 SCTP_DEBUG_PRINTK("unimplemented SCTP_HOST_NAME_ADDRESS\n");
2525 case SCTP_PARAM_SUPPORTED_ADDRESS_TYPES:
2526 /* Turn off the default values first so we'll know which
2527 * ones are really set by the peer.
2529 asoc->peer.ipv4_address = 0;
2530 asoc->peer.ipv6_address = 0;
2532 /* Assume that peer supports the address family
2533 * by which it sends a packet.
2535 if (peer_addr->sa.sa_family == AF_INET6)
2536 asoc->peer.ipv6_address = 1;
2537 else if (peer_addr->sa.sa_family == AF_INET)
2538 asoc->peer.ipv4_address = 1;
2540 /* Cycle through address types; avoid divide by 0. */
2541 sat = ntohs(param.p->length) - sizeof(sctp_paramhdr_t);
2543 sat /= sizeof(__u16);
2545 for (i = 0; i < sat; ++i) {
2546 switch (param.sat->types[i]) {
2547 case SCTP_PARAM_IPV4_ADDRESS:
2548 asoc->peer.ipv4_address = 1;
2551 case SCTP_PARAM_IPV6_ADDRESS:
2552 if (PF_INET6 == asoc->base.sk->sk_family)
2553 asoc->peer.ipv6_address = 1;
2556 case SCTP_PARAM_HOST_NAME_ADDRESS:
2557 asoc->peer.hostname_address = 1;
2560 default: /* Just ignore anything else. */
2566 case SCTP_PARAM_STATE_COOKIE:
2567 asoc->peer.cookie_len =
2568 ntohs(param.p->length) - sizeof(sctp_paramhdr_t);
2569 asoc->peer.cookie = param.cookie->body;
2572 case SCTP_PARAM_HEARTBEAT_INFO:
2573 /* Would be odd to receive, but it causes no problems. */
2576 case SCTP_PARAM_UNRECOGNIZED_PARAMETERS:
2577 /* Rejected during verify stage. */
2580 case SCTP_PARAM_ECN_CAPABLE:
2581 asoc->peer.ecn_capable = 1;
2584 case SCTP_PARAM_ADAPTATION_LAYER_IND:
2585 asoc->peer.adaptation_ind = ntohl(param.aind->adaptation_ind);
2588 case SCTP_PARAM_SET_PRIMARY:
2589 if (!net->sctp.addip_enable)
2592 addr_param = param.v + sizeof(sctp_addip_param_t);
2594 af = sctp_get_af_specific(param_type2af(param.p->type));
2595 af->from_addr_param(&addr, addr_param,
2596 htons(asoc->peer.port), 0);
2598 /* if the address is invalid, we can't process it.
2599 * XXX: see spec for what to do.
2601 if (!af->addr_valid(&addr, NULL, NULL))
2604 t = sctp_assoc_lookup_paddr(asoc, &addr);
2608 sctp_assoc_set_primary(asoc, t);
2611 case SCTP_PARAM_SUPPORTED_EXT:
2612 sctp_process_ext_param(asoc, param);
2615 case SCTP_PARAM_FWD_TSN_SUPPORT:
2616 if (net->sctp.prsctp_enable) {
2617 asoc->peer.prsctp_capable = 1;
2623 case SCTP_PARAM_RANDOM:
2624 if (!net->sctp.auth_enable)
2627 /* Save peer's random parameter */
2628 asoc->peer.peer_random = kmemdup(param.p,
2629 ntohs(param.p->length), gfp);
2630 if (!asoc->peer.peer_random) {
2636 case SCTP_PARAM_HMAC_ALGO:
2637 if (!net->sctp.auth_enable)
2640 /* Save peer's HMAC list */
2641 asoc->peer.peer_hmacs = kmemdup(param.p,
2642 ntohs(param.p->length), gfp);
2643 if (!asoc->peer.peer_hmacs) {
2648 /* Set the default HMAC the peer requested*/
2649 sctp_auth_asoc_set_default_hmac(asoc, param.hmac_algo);
2652 case SCTP_PARAM_CHUNKS:
2653 if (!net->sctp.auth_enable)
2656 asoc->peer.peer_chunks = kmemdup(param.p,
2657 ntohs(param.p->length), gfp);
2658 if (!asoc->peer.peer_chunks)
2663 /* Any unrecognized parameters should have been caught
2664 * and handled by sctp_verify_param() which should be
2665 * called prior to this routine. Simply log the error
2668 SCTP_DEBUG_PRINTK("Ignoring param: %d for association %p.\n",
2669 ntohs(param.p->type), asoc);
2676 /* Select a new verification tag. */
2677 __u32 sctp_generate_tag(const struct sctp_endpoint *ep)
2679 /* I believe that this random number generator complies with RFC1750.
2680 * A tag of 0 is reserved for special cases (e.g. INIT).
2685 get_random_bytes(&x, sizeof(__u32));
2691 /* Select an initial TSN to send during startup. */
2692 __u32 sctp_generate_tsn(const struct sctp_endpoint *ep)
2696 get_random_bytes(&retval, sizeof(__u32));
2701 * ADDIP 3.1.1 Address Configuration Change Chunk (ASCONF)
2703 * 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
2704 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2705 * | Type = 0xC1 | Chunk Flags | Chunk Length |
2706 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2708 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2709 * | Address Parameter |
2710 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2711 * | ASCONF Parameter #1 |
2712 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2716 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2717 * | ASCONF Parameter #N |
2718 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2720 * Address Parameter and other parameter will not be wrapped in this function
2722 static struct sctp_chunk *sctp_make_asconf(struct sctp_association *asoc,
2723 union sctp_addr *addr,
2726 sctp_addiphdr_t asconf;
2727 struct sctp_chunk *retval;
2728 int length = sizeof(asconf) + vparam_len;
2729 union sctp_addr_param addrparam;
2731 struct sctp_af *af = sctp_get_af_specific(addr->v4.sin_family);
2733 addrlen = af->to_addr_param(addr, &addrparam);
2738 /* Create the chunk. */
2739 retval = sctp_make_chunk(asoc, SCTP_CID_ASCONF, 0, length);
2743 asconf.serial = htonl(asoc->addip_serial++);
2745 retval->subh.addip_hdr =
2746 sctp_addto_chunk(retval, sizeof(asconf), &asconf);
2747 retval->param_hdr.v =
2748 sctp_addto_chunk(retval, addrlen, &addrparam);
2754 * 3.2.1 Add IP Address
2756 * 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
2757 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2758 * | Type = 0xC001 | Length = Variable |
2759 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2760 * | ASCONF-Request Correlation ID |
2761 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2762 * | Address Parameter |
2763 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2765 * 3.2.2 Delete IP Address
2767 * 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
2768 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2769 * | Type = 0xC002 | Length = Variable |
2770 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2771 * | ASCONF-Request Correlation ID |
2772 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2773 * | Address Parameter |
2774 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2777 struct sctp_chunk *sctp_make_asconf_update_ip(struct sctp_association *asoc,
2778 union sctp_addr *laddr,
2779 struct sockaddr *addrs,
2783 sctp_addip_param_t param;
2784 struct sctp_chunk *retval;
2785 union sctp_addr_param addr_param;
2786 union sctp_addr *addr;
2789 int paramlen = sizeof(param);
2790 int addr_param_len = 0;
2795 /* Get total length of all the address parameters. */
2797 for (i = 0; i < addrcnt; i++) {
2799 af = sctp_get_af_specific(addr->v4.sin_family);
2800 addr_param_len = af->to_addr_param(addr, &addr_param);
2802 totallen += paramlen;
2803 totallen += addr_param_len;
2805 addr_buf += af->sockaddr_len;
2806 if (asoc->asconf_addr_del_pending && !del_pickup) {
2807 /* reuse the parameter length from the same scope one */
2808 totallen += paramlen;
2809 totallen += addr_param_len;
2811 SCTP_DEBUG_PRINTK("mkasconf_update_ip: picked same-scope del_pending addr, totallen for all addresses is %d\n", totallen);
2815 /* Create an asconf chunk with the required length. */
2816 retval = sctp_make_asconf(asoc, laddr, totallen);
2820 /* Add the address parameters to the asconf chunk. */
2822 for (i = 0; i < addrcnt; i++) {
2824 af = sctp_get_af_specific(addr->v4.sin_family);
2825 addr_param_len = af->to_addr_param(addr, &addr_param);
2826 param.param_hdr.type = flags;
2827 param.param_hdr.length = htons(paramlen + addr_param_len);
2830 sctp_addto_chunk(retval, paramlen, ¶m);
2831 sctp_addto_chunk(retval, addr_param_len, &addr_param);
2833 addr_buf += af->sockaddr_len;
2835 if (flags == SCTP_PARAM_ADD_IP && del_pickup) {
2836 addr = asoc->asconf_addr_del_pending;
2837 af = sctp_get_af_specific(addr->v4.sin_family);
2838 addr_param_len = af->to_addr_param(addr, &addr_param);
2839 param.param_hdr.type = SCTP_PARAM_DEL_IP;
2840 param.param_hdr.length = htons(paramlen + addr_param_len);
2843 sctp_addto_chunk(retval, paramlen, ¶m);
2844 sctp_addto_chunk(retval, addr_param_len, &addr_param);
2850 * 3.2.4 Set Primary IP Address
2852 * 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
2853 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2854 * | Type =0xC004 | Length = Variable |
2855 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2856 * | ASCONF-Request Correlation ID |
2857 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2858 * | Address Parameter |
2859 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2861 * Create an ASCONF chunk with Set Primary IP address parameter.
2863 struct sctp_chunk *sctp_make_asconf_set_prim(struct sctp_association *asoc,
2864 union sctp_addr *addr)
2866 sctp_addip_param_t param;
2867 struct sctp_chunk *retval;
2868 int len = sizeof(param);
2869 union sctp_addr_param addrparam;
2871 struct sctp_af *af = sctp_get_af_specific(addr->v4.sin_family);
2873 addrlen = af->to_addr_param(addr, &addrparam);
2878 /* Create the chunk and make asconf header. */
2879 retval = sctp_make_asconf(asoc, addr, len);
2883 param.param_hdr.type = SCTP_PARAM_SET_PRIMARY;
2884 param.param_hdr.length = htons(len);
2887 sctp_addto_chunk(retval, sizeof(param), ¶m);
2888 sctp_addto_chunk(retval, addrlen, &addrparam);
2893 /* ADDIP 3.1.2 Address Configuration Acknowledgement Chunk (ASCONF-ACK)
2895 * 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
2896 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2897 * | Type = 0x80 | Chunk Flags | Chunk Length |
2898 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2900 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2901 * | ASCONF Parameter Response#1 |
2902 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2906 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2907 * | ASCONF Parameter Response#N |
2908 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2910 * Create an ASCONF_ACK chunk with enough space for the parameter responses.
2912 static struct sctp_chunk *sctp_make_asconf_ack(const struct sctp_association *asoc,
2913 __u32 serial, int vparam_len)
2915 sctp_addiphdr_t asconf;
2916 struct sctp_chunk *retval;
2917 int length = sizeof(asconf) + vparam_len;
2919 /* Create the chunk. */
2920 retval = sctp_make_chunk(asoc, SCTP_CID_ASCONF_ACK, 0, length);
2924 asconf.serial = htonl(serial);
2926 retval->subh.addip_hdr =
2927 sctp_addto_chunk(retval, sizeof(asconf), &asconf);
2932 /* Add response parameters to an ASCONF_ACK chunk. */
2933 static void sctp_add_asconf_response(struct sctp_chunk *chunk, __be32 crr_id,
2934 __be16 err_code, sctp_addip_param_t *asconf_param)
2936 sctp_addip_param_t ack_param;
2937 sctp_errhdr_t err_param;
2938 int asconf_param_len = 0;
2939 int err_param_len = 0;
2940 __be16 response_type;
2942 if (SCTP_ERROR_NO_ERROR == err_code) {
2943 response_type = SCTP_PARAM_SUCCESS_REPORT;
2945 response_type = SCTP_PARAM_ERR_CAUSE;
2946 err_param_len = sizeof(err_param);
2949 ntohs(asconf_param->param_hdr.length);
2952 /* Add Success Indication or Error Cause Indication parameter. */
2953 ack_param.param_hdr.type = response_type;
2954 ack_param.param_hdr.length = htons(sizeof(ack_param) +
2957 ack_param.crr_id = crr_id;
2958 sctp_addto_chunk(chunk, sizeof(ack_param), &ack_param);
2960 if (SCTP_ERROR_NO_ERROR == err_code)
2963 /* Add Error Cause parameter. */
2964 err_param.cause = err_code;
2965 err_param.length = htons(err_param_len + asconf_param_len);
2966 sctp_addto_chunk(chunk, err_param_len, &err_param);
2968 /* Add the failed TLV copied from ASCONF chunk. */
2970 sctp_addto_chunk(chunk, asconf_param_len, asconf_param);
2973 /* Process a asconf parameter. */
2974 static __be16 sctp_process_asconf_param(struct sctp_association *asoc,
2975 struct sctp_chunk *asconf,
2976 sctp_addip_param_t *asconf_param)
2978 struct sctp_transport *peer;
2980 union sctp_addr addr;
2981 union sctp_addr_param *addr_param;
2983 addr_param = (void *)asconf_param + sizeof(sctp_addip_param_t);
2985 if (asconf_param->param_hdr.type != SCTP_PARAM_ADD_IP &&
2986 asconf_param->param_hdr.type != SCTP_PARAM_DEL_IP &&
2987 asconf_param->param_hdr.type != SCTP_PARAM_SET_PRIMARY)
2988 return SCTP_ERROR_UNKNOWN_PARAM;
2990 switch (addr_param->p.type) {
2991 case SCTP_PARAM_IPV6_ADDRESS:
2992 if (!asoc->peer.ipv6_address)
2993 return SCTP_ERROR_DNS_FAILED;
2995 case SCTP_PARAM_IPV4_ADDRESS:
2996 if (!asoc->peer.ipv4_address)
2997 return SCTP_ERROR_DNS_FAILED;
3000 return SCTP_ERROR_DNS_FAILED;
3003 af = sctp_get_af_specific(param_type2af(addr_param->p.type));
3005 return SCTP_ERROR_DNS_FAILED;
3007 af->from_addr_param(&addr, addr_param, htons(asoc->peer.port), 0);
3009 /* ADDIP 4.2.1 This parameter MUST NOT contain a broadcast
3010 * or multicast address.
3011 * (note: wildcard is permitted and requires special handling so
3012 * make sure we check for that)
3014 if (!af->is_any(&addr) && !af->addr_valid(&addr, NULL, asconf->skb))
3015 return SCTP_ERROR_DNS_FAILED;
3017 switch (asconf_param->param_hdr.type) {
3018 case SCTP_PARAM_ADD_IP:
3020 * If the address 0.0.0.0 or ::0 is provided, the source
3021 * address of the packet MUST be added.
3023 if (af->is_any(&addr))
3024 memcpy(&addr, &asconf->source, sizeof(addr));
3026 /* ADDIP 4.3 D9) If an endpoint receives an ADD IP address
3027 * request and does not have the local resources to add this
3028 * new address to the association, it MUST return an Error
3029 * Cause TLV set to the new error code 'Operation Refused
3030 * Due to Resource Shortage'.
3033 peer = sctp_assoc_add_peer(asoc, &addr, GFP_ATOMIC, SCTP_UNCONFIRMED);
3035 return SCTP_ERROR_RSRC_LOW;
3037 /* Start the heartbeat timer. */
3038 if (!mod_timer(&peer->hb_timer, sctp_transport_timeout(peer)))
3039 sctp_transport_hold(peer);
3040 asoc->new_transport = peer;
3042 case SCTP_PARAM_DEL_IP:
3043 /* ADDIP 4.3 D7) If a request is received to delete the
3044 * last remaining IP address of a peer endpoint, the receiver
3045 * MUST send an Error Cause TLV with the error cause set to the
3046 * new error code 'Request to Delete Last Remaining IP Address'.
3048 if (asoc->peer.transport_count == 1)
3049 return SCTP_ERROR_DEL_LAST_IP;
3051 /* ADDIP 4.3 D8) If a request is received to delete an IP
3052 * address which is also the source address of the IP packet
3053 * which contained the ASCONF chunk, the receiver MUST reject
3054 * this request. To reject the request the receiver MUST send
3055 * an Error Cause TLV set to the new error code 'Request to
3056 * Delete Source IP Address'
3058 if (sctp_cmp_addr_exact(&asconf->source, &addr))
3059 return SCTP_ERROR_DEL_SRC_IP;
3062 * If the address 0.0.0.0 or ::0 is provided, all
3063 * addresses of the peer except the source address of the
3064 * packet MUST be deleted.
3066 if (af->is_any(&addr)) {
3067 sctp_assoc_set_primary(asoc, asconf->transport);
3068 sctp_assoc_del_nonprimary_peers(asoc,
3071 sctp_assoc_del_peer(asoc, &addr);
3073 case SCTP_PARAM_SET_PRIMARY:
3074 /* ADDIP Section 4.2.4
3075 * If the address 0.0.0.0 or ::0 is provided, the receiver
3076 * MAY mark the source address of the packet as its
3079 if (af->is_any(&addr))
3080 memcpy(&addr.v4, sctp_source(asconf), sizeof(addr));
3082 peer = sctp_assoc_lookup_paddr(asoc, &addr);
3084 return SCTP_ERROR_DNS_FAILED;
3086 sctp_assoc_set_primary(asoc, peer);
3090 return SCTP_ERROR_NO_ERROR;
3093 /* Verify the ASCONF packet before we process it. */
3094 int sctp_verify_asconf(const struct sctp_association *asoc,
3095 struct sctp_paramhdr *param_hdr, void *chunk_end,
3096 struct sctp_paramhdr **errp) {
3097 sctp_addip_param_t *asconf_param;
3098 union sctp_params param;
3101 param.v = (sctp_paramhdr_t *) param_hdr;
3102 while (param.v <= chunk_end - sizeof(sctp_paramhdr_t)) {
3103 length = ntohs(param.p->length);
3106 if (param.v > chunk_end - length ||
3107 length < sizeof(sctp_paramhdr_t))
3110 switch (param.p->type) {
3111 case SCTP_PARAM_ADD_IP:
3112 case SCTP_PARAM_DEL_IP:
3113 case SCTP_PARAM_SET_PRIMARY:
3114 asconf_param = (sctp_addip_param_t *)param.v;
3115 plen = ntohs(asconf_param->param_hdr.length);
3116 if (plen < sizeof(sctp_addip_param_t) +
3117 sizeof(sctp_paramhdr_t))
3120 case SCTP_PARAM_SUCCESS_REPORT:
3121 case SCTP_PARAM_ADAPTATION_LAYER_IND:
3122 if (length != sizeof(sctp_addip_param_t))
3130 param.v += WORD_ROUND(length);
3133 if (param.v != chunk_end)
3139 /* Process an incoming ASCONF chunk with the next expected serial no. and
3140 * return an ASCONF_ACK chunk to be sent in response.
3142 struct sctp_chunk *sctp_process_asconf(struct sctp_association *asoc,
3143 struct sctp_chunk *asconf)
3145 sctp_addiphdr_t *hdr;
3146 union sctp_addr_param *addr_param;
3147 sctp_addip_param_t *asconf_param;
3148 struct sctp_chunk *asconf_ack;
3154 int all_param_pass = 1;
3156 chunk_len = ntohs(asconf->chunk_hdr->length) - sizeof(sctp_chunkhdr_t);
3157 hdr = (sctp_addiphdr_t *)asconf->skb->data;
3158 serial = ntohl(hdr->serial);
3160 /* Skip the addiphdr and store a pointer to address parameter. */
3161 length = sizeof(sctp_addiphdr_t);
3162 addr_param = (union sctp_addr_param *)(asconf->skb->data + length);
3163 chunk_len -= length;
3165 /* Skip the address parameter and store a pointer to the first
3168 length = ntohs(addr_param->p.length);
3169 asconf_param = (void *)addr_param + length;
3170 chunk_len -= length;
3172 /* create an ASCONF_ACK chunk.
3173 * Based on the definitions of parameters, we know that the size of
3174 * ASCONF_ACK parameters are less than or equal to the fourfold of ASCONF
3177 asconf_ack = sctp_make_asconf_ack(asoc, serial, chunk_len * 4);
3181 /* Process the TLVs contained within the ASCONF chunk. */
3182 while (chunk_len > 0) {
3183 err_code = sctp_process_asconf_param(asoc, asconf,
3186 * If an error response is received for a TLV parameter,
3187 * all TLVs with no response before the failed TLV are
3188 * considered successful if not reported. All TLVs after
3189 * the failed response are considered unsuccessful unless
3190 * a specific success indication is present for the parameter.
3192 if (SCTP_ERROR_NO_ERROR != err_code)
3195 if (!all_param_pass)
3196 sctp_add_asconf_response(asconf_ack,
3197 asconf_param->crr_id, err_code,
3200 /* ADDIP 4.3 D11) When an endpoint receiving an ASCONF to add
3201 * an IP address sends an 'Out of Resource' in its response, it
3202 * MUST also fail any subsequent add or delete requests bundled
3205 if (SCTP_ERROR_RSRC_LOW == err_code)
3208 /* Move to the next ASCONF param. */
3209 length = ntohs(asconf_param->param_hdr.length);
3210 asconf_param = (void *)asconf_param + length;
3211 chunk_len -= length;
3215 asoc->peer.addip_serial++;
3217 /* If we are sending a new ASCONF_ACK hold a reference to it in assoc
3218 * after freeing the reference to old asconf ack if any.
3221 sctp_chunk_hold(asconf_ack);
3222 list_add_tail(&asconf_ack->transmitted_list,
3223 &asoc->asconf_ack_list);
3229 /* Process a asconf parameter that is successfully acked. */
3230 static void sctp_asconf_param_success(struct sctp_association *asoc,
3231 sctp_addip_param_t *asconf_param)
3234 union sctp_addr addr;
3235 struct sctp_bind_addr *bp = &asoc->base.bind_addr;
3236 union sctp_addr_param *addr_param;
3237 struct sctp_transport *transport;
3238 struct sctp_sockaddr_entry *saddr;
3240 addr_param = (void *)asconf_param + sizeof(sctp_addip_param_t);
3242 /* We have checked the packet before, so we do not check again. */
3243 af = sctp_get_af_specific(param_type2af(addr_param->p.type));
3244 af->from_addr_param(&addr, addr_param, htons(bp->port), 0);
3246 switch (asconf_param->param_hdr.type) {
3247 case SCTP_PARAM_ADD_IP:
3248 /* This is always done in BH context with a socket lock
3249 * held, so the list can not change.
3252 list_for_each_entry(saddr, &bp->address_list, list) {
3253 if (sctp_cmp_addr_exact(&saddr->a, &addr))
3254 saddr->state = SCTP_ADDR_SRC;
3257 list_for_each_entry(transport, &asoc->peer.transport_addr_list,
3259 dst_release(transport->dst);
3260 transport->dst = NULL;
3263 case SCTP_PARAM_DEL_IP:
3265 sctp_del_bind_addr(bp, &addr);
3266 if (asoc->asconf_addr_del_pending != NULL &&
3267 sctp_cmp_addr_exact(asoc->asconf_addr_del_pending, &addr)) {
3268 kfree(asoc->asconf_addr_del_pending);
3269 asoc->asconf_addr_del_pending = NULL;
3272 list_for_each_entry(transport, &asoc->peer.transport_addr_list,
3274 dst_release(transport->dst);
3275 transport->dst = NULL;
3283 /* Get the corresponding ASCONF response error code from the ASCONF_ACK chunk
3284 * for the given asconf parameter. If there is no response for this parameter,
3285 * return the error code based on the third argument 'no_err'.
3287 * A7) If an error response is received for a TLV parameter, all TLVs with no
3288 * response before the failed TLV are considered successful if not reported.
3289 * All TLVs after the failed response are considered unsuccessful unless a
3290 * specific success indication is present for the parameter.
3292 static __be16 sctp_get_asconf_response(struct sctp_chunk *asconf_ack,
3293 sctp_addip_param_t *asconf_param,
3296 sctp_addip_param_t *asconf_ack_param;
3297 sctp_errhdr_t *err_param;
3303 err_code = SCTP_ERROR_NO_ERROR;
3305 err_code = SCTP_ERROR_REQ_REFUSED;
3307 asconf_ack_len = ntohs(asconf_ack->chunk_hdr->length) -
3308 sizeof(sctp_chunkhdr_t);
3310 /* Skip the addiphdr from the asconf_ack chunk and store a pointer to
3311 * the first asconf_ack parameter.
3313 length = sizeof(sctp_addiphdr_t);
3314 asconf_ack_param = (sctp_addip_param_t *)(asconf_ack->skb->data +
3316 asconf_ack_len -= length;
3318 while (asconf_ack_len > 0) {
3319 if (asconf_ack_param->crr_id == asconf_param->crr_id) {
3320 switch(asconf_ack_param->param_hdr.type) {
3321 case SCTP_PARAM_SUCCESS_REPORT:
3322 return SCTP_ERROR_NO_ERROR;
3323 case SCTP_PARAM_ERR_CAUSE:
3324 length = sizeof(sctp_addip_param_t);
3325 err_param = (void *)asconf_ack_param + length;
3326 asconf_ack_len -= length;
3327 if (asconf_ack_len > 0)
3328 return err_param->cause;
3330 return SCTP_ERROR_INV_PARAM;
3333 return SCTP_ERROR_INV_PARAM;
3337 length = ntohs(asconf_ack_param->param_hdr.length);
3338 asconf_ack_param = (void *)asconf_ack_param + length;
3339 asconf_ack_len -= length;
3345 /* Process an incoming ASCONF_ACK chunk against the cached last ASCONF chunk. */
3346 int sctp_process_asconf_ack(struct sctp_association *asoc,
3347 struct sctp_chunk *asconf_ack)
3349 struct sctp_chunk *asconf = asoc->addip_last_asconf;
3350 union sctp_addr_param *addr_param;
3351 sctp_addip_param_t *asconf_param;
3353 int asconf_len = asconf->skb->len;
3354 int all_param_pass = 0;
3357 __be16 err_code = SCTP_ERROR_NO_ERROR;
3359 /* Skip the chunkhdr and addiphdr from the last asconf sent and store
3360 * a pointer to address parameter.
3362 length = sizeof(sctp_addip_chunk_t);
3363 addr_param = (union sctp_addr_param *)(asconf->skb->data + length);
3364 asconf_len -= length;
3366 /* Skip the address parameter in the last asconf sent and store a
3367 * pointer to the first asconf parameter.
3369 length = ntohs(addr_param->p.length);
3370 asconf_param = (void *)addr_param + length;
3371 asconf_len -= length;
3374 * A8) If there is no response(s) to specific TLV parameter(s), and no
3375 * failures are indicated, then all request(s) are considered
3378 if (asconf_ack->skb->len == sizeof(sctp_addiphdr_t))
3381 /* Process the TLVs contained in the last sent ASCONF chunk. */
3382 while (asconf_len > 0) {
3384 err_code = SCTP_ERROR_NO_ERROR;
3386 err_code = sctp_get_asconf_response(asconf_ack,
3389 if (no_err && (SCTP_ERROR_NO_ERROR != err_code))
3394 case SCTP_ERROR_NO_ERROR:
3395 sctp_asconf_param_success(asoc, asconf_param);
3398 case SCTP_ERROR_RSRC_LOW:
3402 case SCTP_ERROR_UNKNOWN_PARAM:
3403 /* Disable sending this type of asconf parameter in
3406 asoc->peer.addip_disabled_mask |=
3407 asconf_param->param_hdr.type;
3410 case SCTP_ERROR_REQ_REFUSED:
3411 case SCTP_ERROR_DEL_LAST_IP:
3412 case SCTP_ERROR_DEL_SRC_IP:
3417 /* Skip the processed asconf parameter and move to the next
3420 length = ntohs(asconf_param->param_hdr.length);
3421 asconf_param = (void *)asconf_param + length;
3422 asconf_len -= length;
3425 if (no_err && asoc->src_out_of_asoc_ok) {
3426 asoc->src_out_of_asoc_ok = 0;
3427 sctp_transport_immediate_rtx(asoc->peer.primary_path);
3430 /* Free the cached last sent asconf chunk. */
3431 list_del_init(&asconf->transmitted_list);
3432 sctp_chunk_free(asconf);
3433 asoc->addip_last_asconf = NULL;
3438 /* Make a FWD TSN chunk. */
3439 struct sctp_chunk *sctp_make_fwdtsn(const struct sctp_association *asoc,
3440 __u32 new_cum_tsn, size_t nstreams,
3441 struct sctp_fwdtsn_skip *skiplist)
3443 struct sctp_chunk *retval = NULL;
3444 struct sctp_fwdtsn_hdr ftsn_hdr;
3445 struct sctp_fwdtsn_skip skip;
3449 hint = (nstreams + 1) * sizeof(__u32);
3451 retval = sctp_make_chunk(asoc, SCTP_CID_FWD_TSN, 0, hint);
3456 ftsn_hdr.new_cum_tsn = htonl(new_cum_tsn);
3457 retval->subh.fwdtsn_hdr =
3458 sctp_addto_chunk(retval, sizeof(ftsn_hdr), &ftsn_hdr);
3460 for (i = 0; i < nstreams; i++) {
3461 skip.stream = skiplist[i].stream;
3462 skip.ssn = skiplist[i].ssn;
3463 sctp_addto_chunk(retval, sizeof(skip), &skip);