1 /* SCTP kernel reference 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 reference 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 * The SCTP reference 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 * The SCTP reference 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 #include <linux/types.h>
54 #include <linux/kernel.h>
56 #include <linux/ipv6.h>
57 #include <linux/net.h>
58 #include <linux/inet.h>
59 #include <asm/scatterlist.h>
60 #include <linux/crypto.h>
63 #include <linux/skbuff.h>
64 #include <linux/random.h> /* for get_random_bytes */
65 #include <net/sctp/sctp.h>
66 #include <net/sctp/sm.h>
68 extern kmem_cache_t *sctp_chunk_cachep;
70 /* What was the inbound interface for this chunk? */
71 int sctp_chunk_iif(const struct sctp_chunk *chunk)
76 af = sctp_get_af_specific(ipver2af(chunk->skb->nh.iph->version));
78 iif = af->skb_iif(chunk->skb);
83 /* RFC 2960 3.3.2 Initiation (INIT) (1)
85 * Note 2: The ECN capable field is reserved for future use of
86 * Explicit Congestion Notification.
88 static const struct sctp_paramhdr ecap_param = {
89 SCTP_PARAM_ECN_CAPABLE,
90 __constant_htons(sizeof(struct sctp_paramhdr)),
92 static const struct sctp_paramhdr prsctp_param = {
93 SCTP_PARAM_FWD_TSN_SUPPORT,
94 __constant_htons(sizeof(struct sctp_paramhdr)),
97 /* A helper to initialize to initialize an op error inside a
98 * provided chunk, as most cause codes will be embedded inside an
101 void sctp_init_cause(struct sctp_chunk *chunk, __u16 cause_code,
102 const void *payload, size_t paylen)
108 /* Cause code constants are now defined in network order. */
109 err.cause = cause_code;
110 len = sizeof(sctp_errhdr_t) + paylen;
112 err.length = htons(len);
114 sctp_addto_chunk(chunk, sizeof(sctp_errhdr_t), &err);
115 chunk->subh.err_hdr = sctp_addto_chunk(chunk, paylen, payload);
118 /* 3.3.2 Initiation (INIT) (1)
120 * This chunk is used to initiate a SCTP association between two
121 * endpoints. The format of the INIT chunk is shown below:
124 * 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
125 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
126 * | Type = 1 | Chunk Flags | Chunk Length |
127 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
129 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
130 * | Advertised Receiver Window Credit (a_rwnd) |
131 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
132 * | Number of Outbound Streams | Number of Inbound Streams |
133 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
135 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
137 * / Optional/Variable-Length Parameters /
139 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
142 * The INIT chunk contains the following parameters. Unless otherwise
143 * noted, each parameter MUST only be included once in the INIT chunk.
145 * Fixed Parameters Status
146 * ----------------------------------------------
147 * Initiate Tag Mandatory
148 * Advertised Receiver Window Credit Mandatory
149 * Number of Outbound Streams Mandatory
150 * Number of Inbound Streams Mandatory
151 * Initial TSN Mandatory
153 * Variable Parameters Status Type Value
154 * -------------------------------------------------------------
155 * IPv4 Address (Note 1) Optional 5
156 * IPv6 Address (Note 1) Optional 6
157 * Cookie Preservative Optional 9
158 * Reserved for ECN Capable (Note 2) Optional 32768 (0x8000)
159 * Host Name Address (Note 3) Optional 11
160 * Supported Address Types (Note 4) Optional 12
162 struct sctp_chunk *sctp_make_init(const struct sctp_association *asoc,
163 const struct sctp_bind_addr *bp,
164 int gfp, int vparam_len)
167 union sctp_params addrs;
169 struct sctp_chunk *retval = NULL;
170 int num_types, addrs_len = 0;
172 sctp_supported_addrs_param_t sat;
174 sctp_adaption_ind_param_t aiparam;
176 /* RFC 2960 3.3.2 Initiation (INIT) (1)
178 * Note 1: The INIT chunks can contain multiple addresses that
179 * can be IPv4 and/or IPv6 in any combination.
183 /* Convert the provided bind address list to raw format. */
184 addrs = sctp_bind_addrs_to_raw(bp, &addrs_len, gfp);
186 init.init_tag = htonl(asoc->c.my_vtag);
187 init.a_rwnd = htonl(asoc->rwnd);
188 init.num_outbound_streams = htons(asoc->c.sinit_num_ostreams);
189 init.num_inbound_streams = htons(asoc->c.sinit_max_instreams);
190 init.initial_tsn = htonl(asoc->c.initial_tsn);
192 /* How many address types are needed? */
193 sp = sctp_sk(asoc->base.sk);
194 num_types = sp->pf->supported_addrs(sp, types);
196 chunksize = sizeof(init) + addrs_len + SCTP_SAT_LEN(num_types);
197 chunksize += sizeof(ecap_param);
198 if (sctp_prsctp_enable)
199 chunksize += sizeof(prsctp_param);
200 chunksize += sizeof(aiparam);
201 chunksize += vparam_len;
203 /* RFC 2960 3.3.2 Initiation (INIT) (1)
205 * Note 3: An INIT chunk MUST NOT contain more than one Host
206 * Name address parameter. Moreover, the sender of the INIT
207 * MUST NOT combine any other address types with the Host Name
208 * address in the INIT. The receiver of INIT MUST ignore any
209 * other address types if the Host Name address parameter is
210 * present in the received INIT chunk.
212 * PLEASE DO NOT FIXME [This version does not support Host Name.]
215 retval = sctp_make_chunk(asoc, SCTP_CID_INIT, 0, chunksize);
219 retval->subh.init_hdr =
220 sctp_addto_chunk(retval, sizeof(init), &init);
221 retval->param_hdr.v =
222 sctp_addto_chunk(retval, addrs_len, addrs.v);
224 /* RFC 2960 3.3.2 Initiation (INIT) (1)
226 * Note 4: This parameter, when present, specifies all the
227 * address types the sending endpoint can support. The absence
228 * of this parameter indicates that the sending endpoint can
229 * support any address type.
231 sat.param_hdr.type = SCTP_PARAM_SUPPORTED_ADDRESS_TYPES;
232 sat.param_hdr.length = htons(SCTP_SAT_LEN(num_types));
233 sctp_addto_chunk(retval, sizeof(sat), &sat);
234 sctp_addto_chunk(retval, num_types * sizeof(__u16), &types);
236 sctp_addto_chunk(retval, sizeof(ecap_param), &ecap_param);
237 if (sctp_prsctp_enable)
238 sctp_addto_chunk(retval, sizeof(prsctp_param), &prsctp_param);
239 aiparam.param_hdr.type = SCTP_PARAM_ADAPTION_LAYER_IND;
240 aiparam.param_hdr.length = htons(sizeof(aiparam));
241 aiparam.adaption_ind = htonl(sp->adaption_ind);
242 sctp_addto_chunk(retval, sizeof(aiparam), &aiparam);
249 struct sctp_chunk *sctp_make_init_ack(const struct sctp_association *asoc,
250 const struct sctp_chunk *chunk,
251 int gfp, int unkparam_len)
253 sctp_inithdr_t initack;
254 struct sctp_chunk *retval;
255 union sctp_params addrs;
257 sctp_cookie_param_t *cookie;
260 sctp_adaption_ind_param_t aiparam;
264 /* Note: there may be no addresses to embed. */
265 addrs = sctp_bind_addrs_to_raw(&asoc->base.bind_addr, &addrs_len, gfp);
267 initack.init_tag = htonl(asoc->c.my_vtag);
268 initack.a_rwnd = htonl(asoc->rwnd);
269 initack.num_outbound_streams = htons(asoc->c.sinit_num_ostreams);
270 initack.num_inbound_streams = htons(asoc->c.sinit_max_instreams);
271 initack.initial_tsn = htonl(asoc->c.initial_tsn);
273 /* FIXME: We really ought to build the cookie right
274 * into the packet instead of allocating more fresh memory.
276 cookie = sctp_pack_cookie(asoc->ep, asoc, chunk, &cookie_len,
281 /* Calculate the total size of allocation, include the reserved
282 * space for reporting unknown parameters if it is specified.
284 chunksize = sizeof(initack) + addrs_len + cookie_len + unkparam_len;
286 /* Tell peer that we'll do ECN only if peer advertised such cap. */
287 if (asoc->peer.ecn_capable)
288 chunksize += sizeof(ecap_param);
290 /* Tell peer that we'll do PR-SCTP only if peer advertised. */
291 if (asoc->peer.prsctp_capable)
292 chunksize += sizeof(prsctp_param);
294 chunksize += sizeof(aiparam);
296 /* Now allocate and fill out the chunk. */
297 retval = sctp_make_chunk(asoc, SCTP_CID_INIT_ACK, 0, chunksize);
301 /* Per the advice in RFC 2960 6.4, send this reply to
302 * the source of the INIT packet.
304 retval->transport = chunk->transport;
305 retval->subh.init_hdr =
306 sctp_addto_chunk(retval, sizeof(initack), &initack);
307 retval->param_hdr.v = sctp_addto_chunk(retval, addrs_len, addrs.v);
308 sctp_addto_chunk(retval, cookie_len, cookie);
309 if (asoc->peer.ecn_capable)
310 sctp_addto_chunk(retval, sizeof(ecap_param), &ecap_param);
311 if (asoc->peer.prsctp_capable)
312 sctp_addto_chunk(retval, sizeof(prsctp_param), &prsctp_param);
314 aiparam.param_hdr.type = SCTP_PARAM_ADAPTION_LAYER_IND;
315 aiparam.param_hdr.length = htons(sizeof(aiparam));
316 aiparam.adaption_ind = htonl(sctp_sk(asoc->base.sk)->adaption_ind);
317 sctp_addto_chunk(retval, sizeof(aiparam), &aiparam);
319 /* We need to remove the const qualifier at this point. */
320 retval->asoc = (struct sctp_association *) asoc;
322 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
324 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
325 * HEARTBEAT ACK, * etc.) to the same destination transport
326 * address from which it received the DATA or control chunk
327 * to which it is replying.
329 * [INIT ACK back to where the INIT came from.]
332 retval->transport = chunk->transport;
342 /* 3.3.11 Cookie Echo (COOKIE ECHO) (10):
344 * This chunk is used only during the initialization of an association.
345 * It is sent by the initiator of an association to its peer to complete
346 * the initialization process. This chunk MUST precede any DATA chunk
347 * sent within the association, but MAY be bundled with one or more DATA
348 * chunks in the same packet.
351 * 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
352 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
353 * | Type = 10 |Chunk Flags | Length |
354 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
357 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
361 * Set to zero on transmit and ignored on receipt.
363 * Length: 16 bits (unsigned integer)
365 * Set to the size of the chunk in bytes, including the 4 bytes of
366 * the chunk header and the size of the Cookie.
368 * Cookie: variable size
370 * This field must contain the exact cookie received in the
371 * State Cookie parameter from the previous INIT ACK.
373 * An implementation SHOULD make the cookie as small as possible
374 * to insure interoperability.
376 struct sctp_chunk *sctp_make_cookie_echo(const struct sctp_association *asoc,
377 const struct sctp_chunk *chunk)
379 struct sctp_chunk *retval;
383 cookie = asoc->peer.cookie;
384 cookie_len = asoc->peer.cookie_len;
386 /* Build a cookie echo chunk. */
387 retval = sctp_make_chunk(asoc, SCTP_CID_COOKIE_ECHO, 0, cookie_len);
390 retval->subh.cookie_hdr =
391 sctp_addto_chunk(retval, cookie_len, cookie);
393 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
395 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
396 * HEARTBEAT ACK, * etc.) to the same destination transport
397 * address from which it * received the DATA or control chunk
398 * to which it is replying.
400 * [COOKIE ECHO back to where the INIT ACK came from.]
403 retval->transport = chunk->transport;
409 /* 3.3.12 Cookie Acknowledgement (COOKIE ACK) (11):
411 * This chunk is used only during the initialization of an
412 * association. It is used to acknowledge the receipt of a COOKIE
413 * ECHO chunk. This chunk MUST precede any DATA or SACK chunk sent
414 * within the association, but MAY be bundled with one or more DATA
415 * chunks or SACK chunk in the same SCTP packet.
418 * 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
419 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
420 * | Type = 11 |Chunk Flags | Length = 4 |
421 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
423 * Chunk Flags: 8 bits
425 * Set to zero on transmit and ignored on receipt.
427 struct sctp_chunk *sctp_make_cookie_ack(const struct sctp_association *asoc,
428 const struct sctp_chunk *chunk)
430 struct sctp_chunk *retval;
432 retval = sctp_make_chunk(asoc, SCTP_CID_COOKIE_ACK, 0, 0);
434 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
436 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
437 * HEARTBEAT ACK, * etc.) to the same destination transport
438 * address from which it * received the DATA or control chunk
439 * to which it is replying.
441 * [COOKIE ACK back to where the COOKIE ECHO came from.]
444 retval->transport = chunk->transport;
450 * Appendix A: Explicit Congestion Notification:
453 * RFC 2481 details a specific bit for a sender to send in the header of
454 * its next outbound TCP segment to indicate to its peer that it has
455 * reduced its congestion window. This is termed the CWR bit. For
456 * SCTP the same indication is made by including the CWR chunk.
457 * This chunk contains one data element, i.e. the TSN number that
458 * was sent in the ECNE chunk. This element represents the lowest
459 * TSN number in the datagram that was originally marked with the
463 * 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
464 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
465 * | Chunk Type=13 | Flags=00000000| Chunk Length = 8 |
466 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
467 * | Lowest TSN Number |
468 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
470 * Note: The CWR is considered a Control chunk.
472 struct sctp_chunk *sctp_make_cwr(const struct sctp_association *asoc,
473 const __u32 lowest_tsn,
474 const struct sctp_chunk *chunk)
476 struct sctp_chunk *retval;
479 cwr.lowest_tsn = htonl(lowest_tsn);
480 retval = sctp_make_chunk(asoc, SCTP_CID_ECN_CWR, 0,
481 sizeof(sctp_cwrhdr_t));
486 retval->subh.ecn_cwr_hdr =
487 sctp_addto_chunk(retval, sizeof(cwr), &cwr);
489 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
491 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
492 * HEARTBEAT ACK, * etc.) to the same destination transport
493 * address from which it * received the DATA or control chunk
494 * to which it is replying.
496 * [Report a reduced congestion window back to where the ECNE
500 retval->transport = chunk->transport;
506 /* Make an ECNE chunk. This is a congestion experienced report. */
507 struct sctp_chunk *sctp_make_ecne(const struct sctp_association *asoc,
508 const __u32 lowest_tsn)
510 struct sctp_chunk *retval;
513 ecne.lowest_tsn = htonl(lowest_tsn);
514 retval = sctp_make_chunk(asoc, SCTP_CID_ECN_ECNE, 0,
515 sizeof(sctp_ecnehdr_t));
518 retval->subh.ecne_hdr =
519 sctp_addto_chunk(retval, sizeof(ecne), &ecne);
525 /* Make a DATA chunk for the given association from the provided
526 * parameters. However, do not populate the data payload.
528 struct sctp_chunk *sctp_make_datafrag_empty(struct sctp_association *asoc,
529 const struct sctp_sndrcvinfo *sinfo,
530 int data_len, __u8 flags, __u16 ssn)
532 struct sctp_chunk *retval;
533 struct sctp_datahdr dp;
536 /* We assign the TSN as LATE as possible, not here when
537 * creating the chunk.
540 dp.stream = htons(sinfo->sinfo_stream);
541 dp.ppid = sinfo->sinfo_ppid;
543 /* Set the flags for an unordered send. */
544 if (sinfo->sinfo_flags & MSG_UNORDERED) {
545 flags |= SCTP_DATA_UNORDERED;
550 chunk_len = sizeof(dp) + data_len;
551 retval = sctp_make_chunk(asoc, SCTP_CID_DATA, flags, chunk_len);
555 retval->subh.data_hdr = sctp_addto_chunk(retval, sizeof(dp), &dp);
556 memcpy(&retval->sinfo, sinfo, sizeof(struct sctp_sndrcvinfo));
562 /* Make a DATA chunk for the given association. Populate the data
565 struct sctp_chunk *sctp_make_datafrag(struct sctp_association *asoc,
566 const struct sctp_sndrcvinfo *sinfo,
567 int data_len, const __u8 *data,
568 __u8 flags, __u16 ssn)
570 struct sctp_chunk *retval;
572 retval = sctp_make_datafrag_empty(asoc, sinfo, data_len, flags, ssn);
574 sctp_addto_chunk(retval, data_len, data);
579 /* Make a DATA chunk for the given association to ride on stream id
580 * 'stream', with a payload id of 'payload', and a body of 'data'.
582 struct sctp_chunk *sctp_make_data(struct sctp_association *asoc,
583 const struct sctp_sndrcvinfo *sinfo,
584 int data_len, const __u8 *data)
586 struct sctp_chunk *retval = NULL;
588 retval = sctp_make_data_empty(asoc, sinfo, data_len);
590 sctp_addto_chunk(retval, data_len, data);
594 /* Make a DATA chunk for the given association to ride on stream id
595 * 'stream', with a payload id of 'payload', and a body big enough to
596 * hold 'data_len' octets of data. We use this version when we need
597 * to build the message AFTER allocating memory.
599 struct sctp_chunk *sctp_make_data_empty(struct sctp_association *asoc,
600 const struct sctp_sndrcvinfo *sinfo,
603 __u8 flags = SCTP_DATA_NOT_FRAG;
605 return sctp_make_datafrag_empty(asoc, sinfo, data_len, flags, 0);
608 /* Create a selective ackowledgement (SACK) for the given
609 * association. This reports on which TSN's we've seen to date,
610 * including duplicates and gaps.
612 struct sctp_chunk *sctp_make_sack(const struct sctp_association *asoc)
614 struct sctp_chunk *retval;
615 struct sctp_sackhdr sack;
618 __u16 num_gabs, num_dup_tsns;
619 struct sctp_tsnmap *map = (struct sctp_tsnmap *)&asoc->peer.tsn_map;
621 ctsn = sctp_tsnmap_get_ctsn(map);
622 SCTP_DEBUG_PRINTK("sackCTSNAck sent: 0x%x.\n", ctsn);
624 /* How much room is needed in the chunk? */
625 num_gabs = sctp_tsnmap_num_gabs(map);
626 num_dup_tsns = sctp_tsnmap_num_dups(map);
628 /* Initialize the SACK header. */
629 sack.cum_tsn_ack = htonl(ctsn);
630 sack.a_rwnd = htonl(asoc->a_rwnd);
631 sack.num_gap_ack_blocks = htons(num_gabs);
632 sack.num_dup_tsns = htons(num_dup_tsns);
635 + sizeof(struct sctp_gap_ack_block) * num_gabs
636 + sizeof(__u32) * num_dup_tsns;
638 /* Create the chunk. */
639 retval = sctp_make_chunk(asoc, SCTP_CID_SACK, 0, len);
643 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
645 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
646 * HEARTBEAT ACK, etc.) to the same destination transport
647 * address from which it received the DATA or control chunk to
648 * which it is replying. This rule should also be followed if
649 * the endpoint is bundling DATA chunks together with the
652 * However, when acknowledging multiple DATA chunks received
653 * in packets from different source addresses in a single
654 * SACK, the SACK chunk may be transmitted to one of the
655 * destination transport addresses from which the DATA or
656 * control chunks being acknowledged were received.
658 * [BUG: We do not implement the following paragraph.
659 * Perhaps we should remember the last transport we used for a
660 * SACK and avoid that (if possible) if we have seen any
661 * duplicates. --piggy]
663 * When a receiver of a duplicate DATA chunk sends a SACK to a
664 * multi- homed endpoint it MAY be beneficial to vary the
665 * destination address and not use the source address of the
666 * DATA chunk. The reason being that receiving a duplicate
667 * from a multi-homed endpoint might indicate that the return
668 * path (as specified in the source address of the DATA chunk)
669 * for the SACK is broken.
671 * [Send to the address from which we last received a DATA chunk.]
673 retval->transport = asoc->peer.last_data_from;
675 retval->subh.sack_hdr =
676 sctp_addto_chunk(retval, sizeof(sack), &sack);
678 /* Add the gap ack block information. */
680 sctp_addto_chunk(retval, sizeof(__u32) * num_gabs,
681 sctp_tsnmap_get_gabs(map));
683 /* Add the duplicate TSN information. */
685 sctp_addto_chunk(retval, sizeof(__u32) * num_dup_tsns,
686 sctp_tsnmap_get_dups(map));
692 /* Make a SHUTDOWN chunk. */
693 struct sctp_chunk *sctp_make_shutdown(const struct sctp_association *asoc,
694 const struct sctp_chunk *chunk)
696 struct sctp_chunk *retval;
697 sctp_shutdownhdr_t shut;
700 ctsn = sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map);
701 shut.cum_tsn_ack = htonl(ctsn);
703 retval = sctp_make_chunk(asoc, SCTP_CID_SHUTDOWN, 0,
704 sizeof(sctp_shutdownhdr_t));
708 retval->subh.shutdown_hdr =
709 sctp_addto_chunk(retval, sizeof(shut), &shut);
712 retval->transport = chunk->transport;
717 struct sctp_chunk *sctp_make_shutdown_ack(const struct sctp_association *asoc,
718 const struct sctp_chunk *chunk)
720 struct sctp_chunk *retval;
722 retval = sctp_make_chunk(asoc, SCTP_CID_SHUTDOWN_ACK, 0, 0);
724 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
726 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
727 * HEARTBEAT ACK, * etc.) to the same destination transport
728 * address from which it * received the DATA or control chunk
729 * to which it is replying.
731 * [ACK back to where the SHUTDOWN came from.]
734 retval->transport = chunk->transport;
739 struct sctp_chunk *sctp_make_shutdown_complete(
740 const struct sctp_association *asoc,
741 const struct sctp_chunk *chunk)
743 struct sctp_chunk *retval;
746 /* Maybe set the T-bit if we have no association. */
747 flags |= asoc ? 0 : SCTP_CHUNK_FLAG_T;
749 retval = sctp_make_chunk(asoc, SCTP_CID_SHUTDOWN_COMPLETE, flags, 0);
751 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
753 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
754 * HEARTBEAT ACK, * etc.) to the same destination transport
755 * address from which it * received the DATA or control chunk
756 * to which it is replying.
758 * [Report SHUTDOWN COMPLETE back to where the SHUTDOWN ACK
762 retval->transport = chunk->transport;
767 /* Create an ABORT. Note that we set the T bit if we have no
770 struct sctp_chunk *sctp_make_abort(const struct sctp_association *asoc,
771 const struct sctp_chunk *chunk,
774 struct sctp_chunk *retval;
777 /* Maybe set the T-bit if we have no association. */
778 flags |= asoc ? 0 : SCTP_CHUNK_FLAG_T;
780 retval = sctp_make_chunk(asoc, SCTP_CID_ABORT, flags, hint);
782 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
784 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
785 * HEARTBEAT ACK, * etc.) to the same destination transport
786 * address from which it * received the DATA or control chunk
787 * to which it is replying.
789 * [ABORT back to where the offender came from.]
792 retval->transport = chunk->transport;
797 /* Helper to create ABORT with a NO_USER_DATA error. */
798 struct sctp_chunk *sctp_make_abort_no_data(
799 const struct sctp_association *asoc,
800 const struct sctp_chunk *chunk, __u32 tsn)
802 struct sctp_chunk *retval;
805 retval = sctp_make_abort(asoc, chunk, sizeof(sctp_errhdr_t)
811 /* Put the tsn back into network byte order. */
812 payload = htonl(tsn);
813 sctp_init_cause(retval, SCTP_ERROR_NO_DATA, (const void *)&payload,
816 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
818 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
819 * HEARTBEAT ACK, * etc.) to the same destination transport
820 * address from which it * received the DATA or control chunk
821 * to which it is replying.
823 * [ABORT back to where the offender came from.]
826 retval->transport = chunk->transport;
832 /* Helper to create ABORT with a SCTP_ERROR_USER_ABORT error. */
833 struct sctp_chunk *sctp_make_abort_user(const struct sctp_association *asoc,
834 const struct sctp_chunk *chunk,
835 const struct msghdr *msg)
837 struct sctp_chunk *retval;
838 void *payload = NULL, *payoff;
840 struct iovec *iov = NULL;
845 iovlen = msg->msg_iovlen;
846 paylen = get_user_iov_size(iov, iovlen);
849 retval = sctp_make_abort(asoc, chunk, sizeof(sctp_errhdr_t) + paylen);
854 /* Put the msg_iov together into payload. */
855 payload = kmalloc(paylen, GFP_ATOMIC);
860 for (; iovlen > 0; --iovlen) {
861 if (copy_from_user(payoff, iov->iov_base,iov->iov_len))
863 payoff += iov->iov_len;
868 sctp_init_cause(retval, SCTP_ERROR_USER_ABORT, payload, paylen);
878 sctp_chunk_free(retval);
884 /* Make a HEARTBEAT chunk. */
885 struct sctp_chunk *sctp_make_heartbeat(const struct sctp_association *asoc,
886 const struct sctp_transport *transport,
887 const void *payload, const size_t paylen)
889 struct sctp_chunk *retval = sctp_make_chunk(asoc, SCTP_CID_HEARTBEAT,
895 /* Cast away the 'const', as this is just telling the chunk
896 * what transport it belongs to.
898 retval->transport = (struct sctp_transport *) transport;
899 retval->subh.hbs_hdr = sctp_addto_chunk(retval, paylen, payload);
905 struct sctp_chunk *sctp_make_heartbeat_ack(const struct sctp_association *asoc,
906 const struct sctp_chunk *chunk,
907 const void *payload, const size_t paylen)
909 struct sctp_chunk *retval;
911 retval = sctp_make_chunk(asoc, SCTP_CID_HEARTBEAT_ACK, 0, paylen);
915 retval->subh.hbs_hdr = sctp_addto_chunk(retval, paylen, payload);
917 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
919 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
920 * HEARTBEAT ACK, * etc.) to the same destination transport
921 * address from which it * received the DATA or control chunk
922 * to which it is replying.
924 * [HBACK back to where the HEARTBEAT came from.]
927 retval->transport = chunk->transport;
933 /* Create an Operation Error chunk with the specified space reserved.
934 * This routine can be used for containing multiple causes in the chunk.
936 struct sctp_chunk *sctp_make_op_error_space(
937 const struct sctp_association *asoc,
938 const struct sctp_chunk *chunk,
941 struct sctp_chunk *retval;
943 retval = sctp_make_chunk(asoc, SCTP_CID_ERROR, 0,
944 sizeof(sctp_errhdr_t) + size);
948 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
950 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
951 * HEARTBEAT ACK, etc.) to the same destination transport
952 * address from which it received the DATA or control chunk
953 * to which it is replying.
957 retval->transport = chunk->transport;
963 /* Create an Operation Error chunk. */
964 struct sctp_chunk *sctp_make_op_error(const struct sctp_association *asoc,
965 const struct sctp_chunk *chunk,
966 __u16 cause_code, const void *payload,
969 struct sctp_chunk *retval;
971 retval = sctp_make_op_error_space(asoc, chunk, paylen);
975 sctp_init_cause(retval, cause_code, payload, paylen);
981 /********************************************************************
982 * 2nd Level Abstractions
983 ********************************************************************/
985 /* Turn an skb into a chunk.
986 * FIXME: Eventually move the structure directly inside the skb->cb[].
988 struct sctp_chunk *sctp_chunkify(struct sk_buff *skb,
989 const struct sctp_association *asoc,
992 struct sctp_chunk *retval;
994 retval = kmem_cache_alloc(sctp_chunk_cachep, SLAB_ATOMIC);
998 memset(retval, 0, sizeof(struct sctp_chunk));
1001 SCTP_DEBUG_PRINTK("chunkifying skb %p w/o an sk\n", skb);
1005 retval->asoc = (struct sctp_association *)asoc;
1007 retval->has_tsn = 0;
1008 retval->has_ssn = 0;
1009 retval->rtt_in_progress = 0;
1010 retval->sent_at = 0;
1011 retval->singleton = 1;
1012 retval->end_of_packet = 0;
1013 retval->ecn_ce_done = 0;
1014 retval->pdiscard = 0;
1016 /* sctpimpguide-05.txt Section 2.8.2
1017 * M1) Each time a new DATA chunk is transmitted
1018 * set the 'TSN.Missing.Report' count for that TSN to 0. The
1019 * 'TSN.Missing.Report' count will be used to determine missing chunks
1020 * and when to fast retransmit.
1022 retval->tsn_missing_report = 0;
1023 retval->tsn_gap_acked = 0;
1024 retval->fast_retransmit = 0;
1026 /* If this is a fragmented message, track all fragments
1027 * of the message (for SEND_FAILED).
1031 /* Polish the bead hole. */
1032 INIT_LIST_HEAD(&retval->transmitted_list);
1033 INIT_LIST_HEAD(&retval->frag_list);
1034 SCTP_DBG_OBJCNT_INC(chunk);
1035 atomic_set(&retval->refcnt, 1);
1042 /* Set chunk->source and dest based on the IP header in chunk->skb. */
1043 void sctp_init_addrs(struct sctp_chunk *chunk, union sctp_addr *src,
1044 union sctp_addr *dest)
1046 memcpy(&chunk->source, src, sizeof(union sctp_addr));
1047 memcpy(&chunk->dest, dest, sizeof(union sctp_addr));
1050 /* Extract the source address from a chunk. */
1051 const union sctp_addr *sctp_source(const struct sctp_chunk *chunk)
1053 /* If we have a known transport, use that. */
1054 if (chunk->transport) {
1055 return &chunk->transport->ipaddr;
1057 /* Otherwise, extract it from the IP header. */
1058 return &chunk->source;
1062 /* Create a new chunk, setting the type and flags headers from the
1063 * arguments, reserving enough space for a 'paylen' byte payload.
1065 struct sctp_chunk *sctp_make_chunk(const struct sctp_association *asoc,
1066 __u8 type, __u8 flags, int paylen)
1068 struct sctp_chunk *retval;
1069 sctp_chunkhdr_t *chunk_hdr;
1070 struct sk_buff *skb;
1073 /* No need to allocate LL here, as this is only a chunk. */
1074 skb = alloc_skb(WORD_ROUND(sizeof(sctp_chunkhdr_t) + paylen),
1079 /* Make room for the chunk header. */
1080 chunk_hdr = (sctp_chunkhdr_t *)skb_put(skb, sizeof(sctp_chunkhdr_t));
1081 chunk_hdr->type = type;
1082 chunk_hdr->flags = flags;
1083 chunk_hdr->length = htons(sizeof(sctp_chunkhdr_t));
1085 sk = asoc ? asoc->base.sk : NULL;
1086 retval = sctp_chunkify(skb, asoc, sk);
1092 retval->chunk_hdr = chunk_hdr;
1093 retval->chunk_end = ((__u8 *)chunk_hdr) + sizeof(struct sctp_chunkhdr);
1095 /* Set the skb to the belonging sock for accounting. */
1104 /* Release the memory occupied by a chunk. */
1105 static void sctp_chunk_destroy(struct sctp_chunk *chunk)
1107 /* Free the chunk skb data and the SCTP_chunk stub itself. */
1108 dev_kfree_skb(chunk->skb);
1110 SCTP_DBG_OBJCNT_DEC(chunk);
1111 kmem_cache_free(sctp_chunk_cachep, chunk);
1114 /* Possibly, free the chunk. */
1115 void sctp_chunk_free(struct sctp_chunk *chunk)
1117 /* Make sure that we are not on any list. */
1118 skb_unlink((struct sk_buff *) chunk);
1119 list_del_init(&chunk->transmitted_list);
1121 /* Release our reference on the message tracker. */
1123 sctp_datamsg_put(chunk->msg);
1125 sctp_chunk_put(chunk);
1128 /* Grab a reference to the chunk. */
1129 void sctp_chunk_hold(struct sctp_chunk *ch)
1131 atomic_inc(&ch->refcnt);
1134 /* Release a reference to the chunk. */
1135 void sctp_chunk_put(struct sctp_chunk *ch)
1137 if (atomic_dec_and_test(&ch->refcnt))
1138 sctp_chunk_destroy(ch);
1141 /* Append bytes to the end of a chunk. Will panic if chunk is not big
1144 void *sctp_addto_chunk(struct sctp_chunk *chunk, int len, const void *data)
1148 int chunklen = ntohs(chunk->chunk_hdr->length);
1149 int padlen = chunklen % 4;
1151 padding = skb_put(chunk->skb, padlen);
1152 target = skb_put(chunk->skb, len);
1154 memset(padding, 0, padlen);
1155 memcpy(target, data, len);
1157 /* Adjust the chunk length field. */
1158 chunk->chunk_hdr->length = htons(chunklen + padlen + len);
1159 chunk->chunk_end = chunk->skb->tail;
1164 /* Append bytes from user space to the end of a chunk. Will panic if
1165 * chunk is not big enough.
1166 * Returns a kernel err value.
1168 int sctp_user_addto_chunk(struct sctp_chunk *chunk, int off, int len,
1174 /* Make room in chunk for data. */
1175 target = skb_put(chunk->skb, len);
1177 /* Copy data (whole iovec) into chunk */
1178 if ((err = memcpy_fromiovecend(target, data, off, len)))
1181 /* Adjust the chunk length field. */
1182 chunk->chunk_hdr->length =
1183 htons(ntohs(chunk->chunk_hdr->length) + len);
1184 chunk->chunk_end = chunk->skb->tail;
1190 /* Helper function to assign a TSN if needed. This assumes that both
1191 * the data_hdr and association have already been assigned.
1193 void sctp_chunk_assign_ssn(struct sctp_chunk *chunk)
1201 /* This is the last possible instant to assign a SSN. */
1202 if (chunk->chunk_hdr->flags & SCTP_DATA_UNORDERED) {
1205 sid = htons(chunk->subh.data_hdr->stream);
1206 if (chunk->chunk_hdr->flags & SCTP_DATA_LAST_FRAG)
1207 ssn = sctp_ssn_next(&chunk->asoc->ssnmap->out, sid);
1209 ssn = sctp_ssn_peek(&chunk->asoc->ssnmap->out, sid);
1213 chunk->subh.data_hdr->ssn = ssn;
1217 /* Helper function to assign a TSN if needed. This assumes that both
1218 * the data_hdr and association have already been assigned.
1220 void sctp_chunk_assign_tsn(struct sctp_chunk *chunk)
1222 if (!chunk->has_tsn) {
1223 /* This is the last possible instant to
1226 chunk->subh.data_hdr->tsn =
1227 htonl(sctp_association_get_next_tsn(chunk->asoc));
1232 /* Create a CLOSED association to use with an incoming packet. */
1233 struct sctp_association *sctp_make_temp_asoc(const struct sctp_endpoint *ep,
1234 struct sctp_chunk *chunk, int gfp)
1236 struct sctp_association *asoc;
1237 struct sk_buff *skb;
1241 /* Create the bare association. */
1242 scope = sctp_scope(sctp_source(chunk));
1243 asoc = sctp_association_new(ep, ep->base.sk, scope, gfp);
1248 /* Create an entry for the source address of the packet. */
1249 af = sctp_get_af_specific(ipver2af(skb->nh.iph->version));
1252 af->from_skb(&asoc->c.peer_addr, skb, 1);
1257 sctp_association_free(asoc);
1261 /* Build a cookie representing asoc.
1262 * This INCLUDES the param header needed to put the cookie in the INIT ACK.
1264 sctp_cookie_param_t *sctp_pack_cookie(const struct sctp_endpoint *ep,
1265 const struct sctp_association *asoc,
1266 const struct sctp_chunk *init_chunk,
1268 const __u8 *raw_addrs, int addrs_len)
1270 sctp_cookie_param_t *retval;
1271 struct sctp_signed_cookie *cookie;
1272 struct scatterlist sg;
1273 int headersize, bodysize;
1274 unsigned int keylen;
1277 headersize = sizeof(sctp_paramhdr_t) + SCTP_SECRET_SIZE;
1278 bodysize = sizeof(struct sctp_cookie)
1279 + ntohs(init_chunk->chunk_hdr->length) + addrs_len;
1281 /* Pad out the cookie to a multiple to make the signature
1282 * functions simpler to write.
1284 if (bodysize % SCTP_COOKIE_MULTIPLE)
1285 bodysize += SCTP_COOKIE_MULTIPLE
1286 - (bodysize % SCTP_COOKIE_MULTIPLE);
1287 *cookie_len = headersize + bodysize;
1289 retval = (sctp_cookie_param_t *)kmalloc(*cookie_len, GFP_ATOMIC);
1296 /* Clear this memory since we are sending this data structure
1297 * out on the network.
1299 memset(retval, 0x00, *cookie_len);
1300 cookie = (struct sctp_signed_cookie *) retval->body;
1302 /* Set up the parameter header. */
1303 retval->p.type = SCTP_PARAM_STATE_COOKIE;
1304 retval->p.length = htons(*cookie_len);
1306 /* Copy the cookie part of the association itself. */
1307 cookie->c = asoc->c;
1308 /* Save the raw address list length in the cookie. */
1309 cookie->c.raw_addr_list_len = addrs_len;
1311 /* Remember PR-SCTP capability. */
1312 cookie->c.prsctp_capable = asoc->peer.prsctp_capable;
1314 /* Save adaption indication in the cookie. */
1315 cookie->c.adaption_ind = asoc->peer.adaption_ind;
1317 /* Set an expiration time for the cookie. */
1318 do_gettimeofday(&cookie->c.expiration);
1319 TIMEVAL_ADD(asoc->cookie_life, cookie->c.expiration);
1321 /* Copy the peer's init packet. */
1322 memcpy(&cookie->c.peer_init[0], init_chunk->chunk_hdr,
1323 ntohs(init_chunk->chunk_hdr->length));
1325 /* Copy the raw local address list of the association. */
1326 memcpy((__u8 *)&cookie->c.peer_init[0] +
1327 ntohs(init_chunk->chunk_hdr->length), raw_addrs, addrs_len);
1329 if (sctp_sk(ep->base.sk)->hmac) {
1330 /* Sign the message. */
1331 sg.page = virt_to_page(&cookie->c);
1332 sg.offset = (unsigned long)(&cookie->c) % PAGE_SIZE;
1333 sg.length = bodysize;
1334 keylen = SCTP_SECRET_SIZE;
1335 key = (char *)ep->secret_key[ep->current_key];
1337 sctp_crypto_hmac(sctp_sk(ep->base.sk)->hmac, key, &keylen,
1338 &sg, 1, cookie->signature);
1345 /* Unpack the cookie from COOKIE ECHO chunk, recreating the association. */
1346 struct sctp_association *sctp_unpack_cookie(
1347 const struct sctp_endpoint *ep,
1348 const struct sctp_association *asoc,
1349 struct sctp_chunk *chunk, int gfp,
1350 int *error, struct sctp_chunk **errp)
1352 struct sctp_association *retval = NULL;
1353 struct sctp_signed_cookie *cookie;
1354 struct sctp_cookie *bear_cookie;
1355 int headersize, bodysize, fixed_size;
1356 __u8 digest[SCTP_SIGNATURE_SIZE];
1357 struct scatterlist sg;
1358 unsigned int keylen, len;
1361 struct sk_buff *skb = chunk->skb;
1363 headersize = sizeof(sctp_chunkhdr_t) + SCTP_SECRET_SIZE;
1364 bodysize = ntohs(chunk->chunk_hdr->length) - headersize;
1365 fixed_size = headersize + sizeof(struct sctp_cookie);
1367 /* Verify that the chunk looks like it even has a cookie.
1368 * There must be enough room for our cookie and our peer's
1371 len = ntohs(chunk->chunk_hdr->length);
1372 if (len < fixed_size + sizeof(struct sctp_chunkhdr))
1375 /* Verify that the cookie has been padded out. */
1376 if (bodysize % SCTP_COOKIE_MULTIPLE)
1379 /* Process the cookie. */
1380 cookie = chunk->subh.cookie_hdr;
1381 bear_cookie = &cookie->c;
1383 if (!sctp_sk(ep->base.sk)->hmac)
1386 /* Check the signature. */
1387 keylen = SCTP_SECRET_SIZE;
1388 sg.page = virt_to_page(bear_cookie);
1389 sg.offset = (unsigned long)(bear_cookie) % PAGE_SIZE;
1390 sg.length = bodysize;
1391 key = (char *)ep->secret_key[ep->current_key];
1393 memset(digest, 0x00, sizeof(digest));
1394 sctp_crypto_hmac(sctp_sk(ep->base.sk)->hmac, key, &keylen, &sg,
1397 if (memcmp(digest, cookie->signature, SCTP_SIGNATURE_SIZE)) {
1398 /* Try the previous key. */
1399 key = (char *)ep->secret_key[ep->last_key];
1400 memset(digest, 0x00, sizeof(digest));
1401 sctp_crypto_hmac(sctp_sk(ep->base.sk)->hmac, key, &keylen,
1404 if (memcmp(digest, cookie->signature, SCTP_SIGNATURE_SIZE)) {
1405 /* Yikes! Still bad signature! */
1406 *error = -SCTP_IERROR_BAD_SIG;
1412 /* Check to see if the cookie is stale. If there is already
1413 * an association, there is no need to check cookie's expiration
1414 * for init collision case of lost COOKIE ACK.
1416 if (!asoc && tv_lt(bear_cookie->expiration, skb->stamp)) {
1419 * Section 3.3.10.3 Stale Cookie Error (3)
1423 * Stale Cookie Error: Indicates the receipt of a valid State
1424 * Cookie that has expired.
1426 len = ntohs(chunk->chunk_hdr->length);
1427 *errp = sctp_make_op_error_space(asoc, chunk, len);
1429 suseconds_t usecs = (skb->stamp.tv_sec -
1430 bear_cookie->expiration.tv_sec) * 1000000L +
1431 skb->stamp.tv_usec -
1432 bear_cookie->expiration.tv_usec;
1434 usecs = htonl(usecs);
1435 sctp_init_cause(*errp, SCTP_ERROR_STALE_COOKIE,
1436 &usecs, sizeof(usecs));
1437 *error = -SCTP_IERROR_STALE_COOKIE;
1439 *error = -SCTP_IERROR_NOMEM;
1444 /* Make a new base association. */
1445 scope = sctp_scope(sctp_source(chunk));
1446 retval = sctp_association_new(ep, ep->base.sk, scope, gfp);
1448 *error = -SCTP_IERROR_NOMEM;
1452 /* Set up our peer's port number. */
1453 retval->peer.port = ntohs(chunk->sctp_hdr->source);
1455 /* Populate the association from the cookie. */
1456 memcpy(&retval->c, bear_cookie, sizeof(*bear_cookie));
1458 if (sctp_assoc_set_bind_addr_from_cookie(retval, bear_cookie,
1460 *error = -SCTP_IERROR_NOMEM;
1464 /* Also, add the destination address. */
1465 if (list_empty(&retval->base.bind_addr.address_list)) {
1466 sctp_add_bind_addr(&retval->base.bind_addr, &chunk->dest,
1470 retval->next_tsn = retval->c.initial_tsn;
1471 retval->ctsn_ack_point = retval->next_tsn - 1;
1472 retval->addip_serial = retval->c.initial_tsn;
1473 retval->adv_peer_ack_point = retval->ctsn_ack_point;
1474 retval->peer.prsctp_capable = retval->c.prsctp_capable;
1475 retval->peer.adaption_ind = retval->c.adaption_ind;
1477 /* The INIT stuff will be done by the side effects. */
1482 sctp_association_free(retval);
1487 /* Yikes! The packet is either corrupt or deliberately
1490 *error = -SCTP_IERROR_MALFORMED;
1494 /********************************************************************
1495 * 3rd Level Abstractions
1496 ********************************************************************/
1498 struct __sctp_missing {
1501 } __attribute__((packed));
1504 * Report a missing mandatory parameter.
1506 static int sctp_process_missing_param(const struct sctp_association *asoc,
1507 sctp_param_t paramtype,
1508 struct sctp_chunk *chunk,
1509 struct sctp_chunk **errp)
1511 struct __sctp_missing report;
1514 len = WORD_ROUND(sizeof(report));
1516 /* Make an ERROR chunk, preparing enough room for
1517 * returning multiple unknown parameters.
1520 *errp = sctp_make_op_error_space(asoc, chunk, len);
1523 report.num_missing = htonl(1);
1524 report.type = paramtype;
1525 sctp_init_cause(*errp, SCTP_ERROR_INV_PARAM,
1526 &report, sizeof(report));
1529 /* Stop processing this chunk. */
1533 /* Report an Invalid Mandatory Parameter. */
1534 static int sctp_process_inv_mandatory(const struct sctp_association *asoc,
1535 struct sctp_chunk *chunk,
1536 struct sctp_chunk **errp)
1538 /* Invalid Mandatory Parameter Error has no payload. */
1541 *errp = sctp_make_op_error_space(asoc, chunk, 0);
1544 sctp_init_cause(*errp, SCTP_ERROR_INV_PARAM, NULL, 0);
1546 /* Stop processing this chunk. */
1550 /* Do not attempt to handle the HOST_NAME parm. However, do
1551 * send back an indicator to the peer.
1553 static int sctp_process_hn_param(const struct sctp_association *asoc,
1554 union sctp_params param,
1555 struct sctp_chunk *chunk,
1556 struct sctp_chunk **errp)
1558 __u16 len = ntohs(param.p->length);
1560 /* Make an ERROR chunk. */
1562 *errp = sctp_make_op_error_space(asoc, chunk, len);
1565 sctp_init_cause(*errp, SCTP_ERROR_DNS_FAILED,
1568 /* Stop processing this chunk. */
1572 /* RFC 3.2.1 & the Implementers Guide 2.2.
1574 * The Parameter Types are encoded such that the
1575 * highest-order two bits specify the action that must be
1576 * taken if the processing endpoint does not recognize the
1579 * 00 - Stop processing this SCTP chunk and discard it,
1580 * do not process any further chunks within it.
1582 * 01 - Stop processing this SCTP chunk and discard it,
1583 * do not process any further chunks within it, and report
1584 * the unrecognized parameter in an 'Unrecognized
1585 * Parameter Type' (in either an ERROR or in the INIT ACK).
1587 * 10 - Skip this parameter and continue processing.
1589 * 11 - Skip this parameter and continue processing but
1590 * report the unrecognized parameter in an
1591 * 'Unrecognized Parameter Type' (in either an ERROR or in
1595 * 0 - discard the chunk
1596 * 1 - continue with the chunk
1598 static int sctp_process_unk_param(const struct sctp_association *asoc,
1599 union sctp_params param,
1600 struct sctp_chunk *chunk,
1601 struct sctp_chunk **errp)
1605 switch (param.p->type & SCTP_PARAM_ACTION_MASK) {
1606 case SCTP_PARAM_ACTION_DISCARD:
1609 case SCTP_PARAM_ACTION_DISCARD_ERR:
1611 /* Make an ERROR chunk, preparing enough room for
1612 * returning multiple unknown parameters.
1615 *errp = sctp_make_op_error_space(asoc, chunk,
1616 ntohs(chunk->chunk_hdr->length));
1619 sctp_init_cause(*errp, SCTP_ERROR_UNKNOWN_PARAM,
1621 WORD_ROUND(ntohs(param.p->length)));
1624 case SCTP_PARAM_ACTION_SKIP:
1626 case SCTP_PARAM_ACTION_SKIP_ERR:
1627 /* Make an ERROR chunk, preparing enough room for
1628 * returning multiple unknown parameters.
1631 *errp = sctp_make_op_error_space(asoc, chunk,
1632 ntohs(chunk->chunk_hdr->length));
1635 sctp_init_cause(*errp, SCTP_ERROR_UNKNOWN_PARAM,
1637 WORD_ROUND(ntohs(param.p->length)));
1639 /* If there is no memory for generating the ERROR
1640 * report as specified, an ABORT will be triggered
1641 * to the peer and the association won't be
1655 /* Find unrecognized parameters in the chunk.
1657 * 0 - discard the chunk
1658 * 1 - continue with the chunk
1660 static int sctp_verify_param(const struct sctp_association *asoc,
1661 union sctp_params param,
1663 struct sctp_chunk *chunk,
1664 struct sctp_chunk **err_chunk)
1668 /* FIXME - This routine is not looking at each parameter per the
1669 * chunk type, i.e., unrecognized parameters should be further
1670 * identified based on the chunk id.
1673 switch (param.p->type) {
1674 case SCTP_PARAM_IPV4_ADDRESS:
1675 case SCTP_PARAM_IPV6_ADDRESS:
1676 case SCTP_PARAM_COOKIE_PRESERVATIVE:
1677 case SCTP_PARAM_SUPPORTED_ADDRESS_TYPES:
1678 case SCTP_PARAM_STATE_COOKIE:
1679 case SCTP_PARAM_HEARTBEAT_INFO:
1680 case SCTP_PARAM_UNRECOGNIZED_PARAMETERS:
1681 case SCTP_PARAM_ECN_CAPABLE:
1682 case SCTP_PARAM_ADAPTION_LAYER_IND:
1685 case SCTP_PARAM_HOST_NAME_ADDRESS:
1686 /* Tell the peer, we won't support this param. */
1687 return sctp_process_hn_param(asoc, param, chunk, err_chunk);
1688 case SCTP_PARAM_FWD_TSN_SUPPORT:
1689 if (sctp_prsctp_enable)
1693 SCTP_DEBUG_PRINTK("Unrecognized param: %d for chunk %d.\n",
1694 ntohs(param.p->type), cid);
1695 return sctp_process_unk_param(asoc, param, chunk, err_chunk);
1702 /* Verify the INIT packet before we process it. */
1703 int sctp_verify_init(const struct sctp_association *asoc,
1705 sctp_init_chunk_t *peer_init,
1706 struct sctp_chunk *chunk,
1707 struct sctp_chunk **errp)
1709 union sctp_params param;
1712 /* Verify stream values are non-zero. */
1713 if ((0 == peer_init->init_hdr.num_outbound_streams) ||
1714 (0 == peer_init->init_hdr.num_inbound_streams)) {
1716 sctp_process_inv_mandatory(asoc, chunk, errp);
1720 /* Check for missing mandatory parameters. */
1721 sctp_walk_params(param, peer_init, init_hdr.params) {
1723 if (SCTP_PARAM_STATE_COOKIE == param.p->type)
1726 } /* for (loop through all parameters) */
1728 /* The only missing mandatory param possible today is
1729 * the state cookie for an INIT-ACK chunk.
1731 if ((SCTP_CID_INIT_ACK == cid) && !has_cookie) {
1732 sctp_process_missing_param(asoc, SCTP_PARAM_STATE_COOKIE,
1737 /* Find unrecognized parameters. */
1739 sctp_walk_params(param, peer_init, init_hdr.params) {
1741 if (!sctp_verify_param(asoc, param, cid, chunk, errp)) {
1742 if (SCTP_PARAM_HOST_NAME_ADDRESS == param.p->type)
1748 } /* for (loop through all parameters) */
1753 /* Unpack the parameters in an INIT packet into an association.
1754 * Returns 0 on failure, else success.
1755 * FIXME: This is an association method.
1757 int sctp_process_init(struct sctp_association *asoc, sctp_cid_t cid,
1758 const union sctp_addr *peer_addr,
1759 sctp_init_chunk_t *peer_init, int gfp)
1761 union sctp_params param;
1762 struct sctp_transport *transport;
1763 struct list_head *pos, *temp;
1766 /* We must include the address that the INIT packet came from.
1767 * This is the only address that matters for an INIT packet.
1768 * When processing a COOKIE ECHO, we retrieve the from address
1769 * of the INIT from the cookie.
1772 /* This implementation defaults to making the first transport
1773 * added as the primary transport. The source address seems to
1774 * be a a better choice than any of the embedded addresses.
1777 if(!sctp_assoc_add_peer(asoc, peer_addr, gfp))
1780 /* Process the initialization parameters. */
1782 sctp_walk_params(param, peer_init, init_hdr.params) {
1784 if (!sctp_process_param(asoc, param, peer_addr, gfp))
1788 /* The fixed INIT headers are always in network byte
1791 asoc->peer.i.init_tag =
1792 ntohl(peer_init->init_hdr.init_tag);
1793 asoc->peer.i.a_rwnd =
1794 ntohl(peer_init->init_hdr.a_rwnd);
1795 asoc->peer.i.num_outbound_streams =
1796 ntohs(peer_init->init_hdr.num_outbound_streams);
1797 asoc->peer.i.num_inbound_streams =
1798 ntohs(peer_init->init_hdr.num_inbound_streams);
1799 asoc->peer.i.initial_tsn =
1800 ntohl(peer_init->init_hdr.initial_tsn);
1802 /* Apply the upper bounds for output streams based on peer's
1803 * number of inbound streams.
1805 if (asoc->c.sinit_num_ostreams >
1806 ntohs(peer_init->init_hdr.num_inbound_streams)) {
1807 asoc->c.sinit_num_ostreams =
1808 ntohs(peer_init->init_hdr.num_inbound_streams);
1811 if (asoc->c.sinit_max_instreams >
1812 ntohs(peer_init->init_hdr.num_outbound_streams)) {
1813 asoc->c.sinit_max_instreams =
1814 ntohs(peer_init->init_hdr.num_outbound_streams);
1817 /* Copy Initiation tag from INIT to VT_peer in cookie. */
1818 asoc->c.peer_vtag = asoc->peer.i.init_tag;
1820 /* Peer Rwnd : Current calculated value of the peer's rwnd. */
1821 asoc->peer.rwnd = asoc->peer.i.a_rwnd;
1823 /* Copy cookie in case we need to resend COOKIE-ECHO. */
1824 cookie = asoc->peer.cookie;
1826 asoc->peer.cookie = kmalloc(asoc->peer.cookie_len, gfp);
1827 if (!asoc->peer.cookie)
1829 memcpy(asoc->peer.cookie, cookie, asoc->peer.cookie_len);
1832 /* RFC 2960 7.2.1 The initial value of ssthresh MAY be arbitrarily
1833 * high (for example, implementations MAY use the size of the receiver
1834 * advertised window).
1836 list_for_each(pos, &asoc->peer.transport_addr_list) {
1837 transport = list_entry(pos, struct sctp_transport, transports);
1838 transport->ssthresh = asoc->peer.i.a_rwnd;
1841 /* Set up the TSN tracking pieces. */
1842 sctp_tsnmap_init(&asoc->peer.tsn_map, SCTP_TSN_MAP_SIZE,
1843 asoc->peer.i.initial_tsn);
1845 /* RFC 2960 6.5 Stream Identifier and Stream Sequence Number
1847 * The stream sequence number in all the streams shall start
1848 * from 0 when the association is established. Also, when the
1849 * stream sequence number reaches the value 65535 the next
1850 * stream sequence number shall be set to 0.
1853 /* Allocate storage for the negotiated streams if it is not a temporary * association.
1859 asoc->ssnmap = sctp_ssnmap_new(asoc->c.sinit_max_instreams,
1860 asoc->c.sinit_num_ostreams, gfp);
1865 if (unlikely(!idr_pre_get(&sctp_assocs_id, gfp)))
1867 spin_lock_bh(&sctp_assocs_id_lock);
1868 error = idr_get_new_above(&sctp_assocs_id, (void *)asoc, 1,
1870 spin_unlock_bh(&sctp_assocs_id_lock);
1871 if (error == -EAGAIN)
1876 asoc->assoc_id = (sctp_assoc_t) assoc_id;
1879 /* ADDIP Section 4.1 ASCONF Chunk Procedures
1881 * When an endpoint has an ASCONF signaled change to be sent to the
1882 * remote endpoint it should do the following:
1884 * A2) A serial number should be assigned to the Chunk. The serial
1885 * number should be a monotonically increasing number. All serial
1886 * numbers are defined to be initialized at the start of the
1887 * association to the same value as the Initial TSN.
1889 asoc->peer.addip_serial = asoc->peer.i.initial_tsn - 1;
1893 /* Release the transport structures. */
1894 list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
1895 transport = list_entry(pos, struct sctp_transport, transports);
1897 sctp_transport_free(transport);
1904 /* Update asoc with the option described in param.
1906 * RFC2960 3.3.2.1 Optional/Variable Length Parameters in INIT
1908 * asoc is the association to update.
1909 * param is the variable length parameter to use for update.
1910 * cid tells us if this is an INIT, INIT ACK or COOKIE ECHO.
1911 * If the current packet is an INIT we want to minimize the amount of
1912 * work we do. In particular, we should not build transport
1913 * structures for the addresses.
1915 int sctp_process_param(struct sctp_association *asoc, union sctp_params param,
1916 const union sctp_addr *peer_addr, int gfp)
1918 union sctp_addr addr;
1926 /* We maintain all INIT parameters in network byte order all the
1927 * time. This allows us to not worry about whether the parameters
1928 * came from a fresh INIT, and INIT ACK, or were stored in a cookie.
1930 switch (param.p->type) {
1931 case SCTP_PARAM_IPV6_ADDRESS:
1932 if (PF_INET6 != asoc->base.sk->sk_family)
1935 case SCTP_PARAM_IPV4_ADDRESS:
1936 af = sctp_get_af_specific(param_type2af(param.p->type));
1937 af->from_addr_param(&addr, param.addr, asoc->peer.port, 0);
1938 scope = sctp_scope(peer_addr);
1939 if (sctp_in_scope(&addr, scope))
1940 if (!sctp_assoc_add_peer(asoc, &addr, gfp))
1944 case SCTP_PARAM_COOKIE_PRESERVATIVE:
1945 if (!sctp_cookie_preserve_enable)
1948 stale = ntohl(param.life->lifespan_increment);
1950 /* Suggested Cookie Life span increment's unit is msec,
1953 asoc->cookie_life.tv_sec += stale / 1000;
1954 asoc->cookie_life.tv_usec += (stale % 1000) * 1000;
1957 case SCTP_PARAM_HOST_NAME_ADDRESS:
1958 SCTP_DEBUG_PRINTK("unimplemented SCTP_HOST_NAME_ADDRESS\n");
1961 case SCTP_PARAM_SUPPORTED_ADDRESS_TYPES:
1962 /* Turn off the default values first so we'll know which
1963 * ones are really set by the peer.
1965 asoc->peer.ipv4_address = 0;
1966 asoc->peer.ipv6_address = 0;
1968 /* Cycle through address types; avoid divide by 0. */
1969 sat = ntohs(param.p->length) - sizeof(sctp_paramhdr_t);
1971 sat /= sizeof(__u16);
1973 for (i = 0; i < sat; ++i) {
1974 switch (param.sat->types[i]) {
1975 case SCTP_PARAM_IPV4_ADDRESS:
1976 asoc->peer.ipv4_address = 1;
1979 case SCTP_PARAM_IPV6_ADDRESS:
1980 asoc->peer.ipv6_address = 1;
1983 case SCTP_PARAM_HOST_NAME_ADDRESS:
1984 asoc->peer.hostname_address = 1;
1987 default: /* Just ignore anything else. */
1993 case SCTP_PARAM_STATE_COOKIE:
1994 asoc->peer.cookie_len =
1995 ntohs(param.p->length) - sizeof(sctp_paramhdr_t);
1996 asoc->peer.cookie = param.cookie->body;
1999 case SCTP_PARAM_HEARTBEAT_INFO:
2000 /* Would be odd to receive, but it causes no problems. */
2003 case SCTP_PARAM_UNRECOGNIZED_PARAMETERS:
2004 /* Rejected during verify stage. */
2007 case SCTP_PARAM_ECN_CAPABLE:
2008 asoc->peer.ecn_capable = 1;
2011 case SCTP_PARAM_ADAPTION_LAYER_IND:
2012 asoc->peer.adaption_ind = param.aind->adaption_ind;
2015 case SCTP_PARAM_FWD_TSN_SUPPORT:
2016 if (sctp_prsctp_enable) {
2017 asoc->peer.prsctp_capable = 1;
2022 /* Any unrecognized parameters should have been caught
2023 * and handled by sctp_verify_param() which should be
2024 * called prior to this routine. Simply log the error
2027 SCTP_DEBUG_PRINTK("Ignoring param: %d for association %p.\n",
2028 ntohs(param.p->type), asoc);
2035 /* Select a new verification tag. */
2036 __u32 sctp_generate_tag(const struct sctp_endpoint *ep)
2038 /* I believe that this random number generator complies with RFC1750.
2039 * A tag of 0 is reserved for special cases (e.g. INIT).
2044 get_random_bytes(&x, sizeof(__u32));
2050 /* Select an initial TSN to send during startup. */
2051 __u32 sctp_generate_tsn(const struct sctp_endpoint *ep)
2055 get_random_bytes(&retval, sizeof(__u32));
2060 * ADDIP 3.1.1 Address Configuration Change Chunk (ASCONF)
2062 * 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
2063 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2064 * | Type = 0xC1 | Chunk Flags | Chunk Length |
2065 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2067 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2068 * | Address Parameter |
2069 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2070 * | ASCONF Parameter #1 |
2071 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2075 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2076 * | ASCONF Parameter #N |
2077 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2079 * Address Parameter and other parameter will not be wrapped in this function
2081 struct sctp_chunk *sctp_make_asconf(struct sctp_association *asoc,
2082 union sctp_addr *addr, int vparam_len)
2084 sctp_addiphdr_t asconf;
2085 struct sctp_chunk *retval;
2086 int length = sizeof(asconf) + vparam_len;
2087 union sctp_addr_param addrparam;
2089 struct sctp_af *af = sctp_get_af_specific(addr->v4.sin_family);
2091 addrlen = af->to_addr_param(addr, &addrparam);
2096 /* Create the chunk. */
2097 retval = sctp_make_chunk(asoc, SCTP_CID_ASCONF, 0, length);
2101 asconf.serial = htonl(asoc->addip_serial++);
2103 retval->subh.addip_hdr =
2104 sctp_addto_chunk(retval, sizeof(asconf), &asconf);
2105 retval->param_hdr.v =
2106 sctp_addto_chunk(retval, addrlen, &addrparam);
2112 * 3.2.1 Add IP Address
2114 * 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
2115 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2116 * | Type = 0xC001 | Length = Variable |
2117 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2118 * | ASCONF-Request Correlation ID |
2119 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2120 * | Address Parameter |
2121 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2123 * 3.2.2 Delete IP Address
2125 * 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
2126 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2127 * | Type = 0xC002 | Length = Variable |
2128 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2129 * | ASCONF-Request Correlation ID |
2130 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2131 * | Address Parameter |
2132 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2135 struct sctp_chunk *sctp_make_asconf_update_ip(struct sctp_association *asoc,
2136 union sctp_addr *laddr,
2137 struct sockaddr *addrs,
2141 sctp_addip_param_t param;
2142 struct sctp_chunk *retval;
2143 union sctp_addr_param addr_param;
2144 union sctp_addr *addr;
2147 int paramlen = sizeof(param);
2148 int addr_param_len = 0;
2152 /* Get total length of all the address parameters. */
2154 for (i = 0; i < addrcnt; i++) {
2155 addr = (union sctp_addr *)addr_buf;
2156 af = sctp_get_af_specific(addr->v4.sin_family);
2157 addr_param_len = af->to_addr_param(addr, &addr_param);
2159 totallen += paramlen;
2160 totallen += addr_param_len;
2162 addr_buf += af->sockaddr_len;
2165 /* Create an asconf chunk with the required length. */
2166 retval = sctp_make_asconf(asoc, laddr, totallen);
2170 /* Add the address parameters to the asconf chunk. */
2172 for (i = 0; i < addrcnt; i++) {
2173 addr = (union sctp_addr *)addr_buf;
2174 af = sctp_get_af_specific(addr->v4.sin_family);
2175 addr_param_len = af->to_addr_param(addr, &addr_param);
2176 param.param_hdr.type = flags;
2177 param.param_hdr.length = htons(paramlen + addr_param_len);
2180 sctp_addto_chunk(retval, paramlen, ¶m);
2181 sctp_addto_chunk(retval, addr_param_len, &addr_param);
2183 addr_buf += af->sockaddr_len;
2189 * 3.2.4 Set Primary IP Address
2191 * 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
2192 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2193 * | Type =0xC004 | Length = Variable |
2194 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2195 * | ASCONF-Request Correlation ID |
2196 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2197 * | Address Parameter |
2198 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2200 * Create an ASCONF chunk with Set Primary IP address parameter.
2202 struct sctp_chunk *sctp_make_asconf_set_prim(struct sctp_association *asoc,
2203 union sctp_addr *addr)
2205 sctp_addip_param_t param;
2206 struct sctp_chunk *retval;
2207 int len = sizeof(param);
2208 union sctp_addr_param addrparam;
2210 struct sctp_af *af = sctp_get_af_specific(addr->v4.sin_family);
2212 addrlen = af->to_addr_param(addr, &addrparam);
2217 /* Create the chunk and make asconf header. */
2218 retval = sctp_make_asconf(asoc, addr, len);
2222 param.param_hdr.type = SCTP_PARAM_SET_PRIMARY;
2223 param.param_hdr.length = htons(len);
2226 sctp_addto_chunk(retval, sizeof(param), ¶m);
2227 sctp_addto_chunk(retval, addrlen, &addrparam);
2232 /* ADDIP 3.1.2 Address Configuration Acknowledgement Chunk (ASCONF-ACK)
2234 * 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
2235 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2236 * | Type = 0x80 | Chunk Flags | Chunk Length |
2237 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2239 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2240 * | ASCONF Parameter Response#1 |
2241 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2245 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2246 * | ASCONF Parameter Response#N |
2247 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2249 * Create an ASCONF_ACK chunk with enough space for the parameter responses.
2251 struct sctp_chunk *sctp_make_asconf_ack(const struct sctp_association *asoc,
2252 __u32 serial, int vparam_len)
2254 sctp_addiphdr_t asconf;
2255 struct sctp_chunk *retval;
2256 int length = sizeof(asconf) + vparam_len;
2258 /* Create the chunk. */
2259 retval = sctp_make_chunk(asoc, SCTP_CID_ASCONF_ACK, 0, length);
2263 asconf.serial = htonl(serial);
2265 retval->subh.addip_hdr =
2266 sctp_addto_chunk(retval, sizeof(asconf), &asconf);
2271 /* Add response parameters to an ASCONF_ACK chunk. */
2272 static void sctp_add_asconf_response(struct sctp_chunk *chunk, __u32 crr_id,
2273 __u16 err_code, sctp_addip_param_t *asconf_param)
2275 sctp_addip_param_t ack_param;
2276 sctp_errhdr_t err_param;
2277 int asconf_param_len = 0;
2278 int err_param_len = 0;
2279 __u16 response_type;
2281 if (SCTP_ERROR_NO_ERROR == err_code) {
2282 response_type = SCTP_PARAM_SUCCESS_REPORT;
2284 response_type = SCTP_PARAM_ERR_CAUSE;
2285 err_param_len = sizeof(err_param);
2288 ntohs(asconf_param->param_hdr.length);
2291 /* Add Success Indication or Error Cause Indication parameter. */
2292 ack_param.param_hdr.type = response_type;
2293 ack_param.param_hdr.length = htons(sizeof(ack_param) +
2296 ack_param.crr_id = crr_id;
2297 sctp_addto_chunk(chunk, sizeof(ack_param), &ack_param);
2299 if (SCTP_ERROR_NO_ERROR == err_code)
2302 /* Add Error Cause parameter. */
2303 err_param.cause = err_code;
2304 err_param.length = htons(err_param_len + asconf_param_len);
2305 sctp_addto_chunk(chunk, err_param_len, &err_param);
2307 /* Add the failed TLV copied from ASCONF chunk. */
2309 sctp_addto_chunk(chunk, asconf_param_len, asconf_param);
2312 /* Process a asconf parameter. */
2313 static __u16 sctp_process_asconf_param(struct sctp_association *asoc,
2314 struct sctp_chunk *asconf,
2315 sctp_addip_param_t *asconf_param)
2317 struct sctp_transport *peer;
2319 union sctp_addr addr;
2320 struct list_head *pos;
2321 union sctp_addr_param *addr_param;
2323 addr_param = (union sctp_addr_param *)
2324 ((void *)asconf_param + sizeof(sctp_addip_param_t));
2326 af = sctp_get_af_specific(param_type2af(addr_param->v4.param_hdr.type));
2328 return SCTP_ERROR_INV_PARAM;
2330 af->from_addr_param(&addr, addr_param, asoc->peer.port, 0);
2331 switch (asconf_param->param_hdr.type) {
2332 case SCTP_PARAM_ADD_IP:
2333 /* ADDIP 4.3 D9) If an endpoint receives an ADD IP address
2334 * request and does not have the local resources to add this
2335 * new address to the association, it MUST return an Error
2336 * Cause TLV set to the new error code 'Operation Refused
2337 * Due to Resource Shortage'.
2340 peer = sctp_assoc_add_peer(asoc, &addr, GFP_ATOMIC);
2342 return SCTP_ERROR_RSRC_LOW;
2344 /* Start the heartbeat timer. */
2345 if (!mod_timer(&peer->hb_timer, sctp_transport_timeout(peer)))
2346 sctp_transport_hold(peer);
2348 case SCTP_PARAM_DEL_IP:
2349 /* ADDIP 4.3 D7) If a request is received to delete the
2350 * last remaining IP address of a peer endpoint, the receiver
2351 * MUST send an Error Cause TLV with the error cause set to the
2352 * new error code 'Request to Delete Last Remaining IP Address'.
2354 pos = asoc->peer.transport_addr_list.next;
2355 if (pos->next == &asoc->peer.transport_addr_list)
2356 return SCTP_ERROR_DEL_LAST_IP;
2358 /* ADDIP 4.3 D8) If a request is received to delete an IP
2359 * address which is also the source address of the IP packet
2360 * which contained the ASCONF chunk, the receiver MUST reject
2361 * this request. To reject the request the receiver MUST send
2362 * an Error Cause TLV set to the new error code 'Request to
2363 * Delete Source IP Address'
2365 if (sctp_cmp_addr_exact(sctp_source(asconf), &addr))
2366 return SCTP_ERROR_DEL_SRC_IP;
2368 sctp_assoc_del_peer(asoc, &addr);
2370 case SCTP_PARAM_SET_PRIMARY:
2371 peer = sctp_assoc_lookup_paddr(asoc, &addr);
2373 return SCTP_ERROR_INV_PARAM;
2375 sctp_assoc_set_primary(asoc, peer);
2378 return SCTP_ERROR_INV_PARAM;
2382 return SCTP_ERROR_NO_ERROR;
2385 /* Process an incoming ASCONF chunk with the next expected serial no. and
2386 * return an ASCONF_ACK chunk to be sent in response.
2388 struct sctp_chunk *sctp_process_asconf(struct sctp_association *asoc,
2389 struct sctp_chunk *asconf)
2391 sctp_addiphdr_t *hdr;
2392 union sctp_addr_param *addr_param;
2393 sctp_addip_param_t *asconf_param;
2394 struct sctp_chunk *asconf_ack;
2398 int chunk_len = asconf->skb->len;
2400 int all_param_pass = 1;
2402 hdr = (sctp_addiphdr_t *)asconf->skb->data;
2403 serial = ntohl(hdr->serial);
2405 /* Skip the addiphdr and store a pointer to address parameter. */
2406 length = sizeof(sctp_addiphdr_t);
2407 addr_param = (union sctp_addr_param *)(asconf->skb->data + length);
2408 chunk_len -= length;
2410 /* Skip the address parameter and store a pointer to the first
2413 length = ntohs(addr_param->v4.param_hdr.length);
2414 asconf_param = (sctp_addip_param_t *)((void *)addr_param + length);
2415 chunk_len -= length;
2417 /* create an ASCONF_ACK chunk.
2418 * Based on the definitions of parameters, we know that the size of
2419 * ASCONF_ACK parameters are less than or equal to the twice of ASCONF
2422 asconf_ack = sctp_make_asconf_ack(asoc, serial, chunk_len * 2);
2426 /* Process the TLVs contained within the ASCONF chunk. */
2427 while (chunk_len > 0) {
2428 err_code = sctp_process_asconf_param(asoc, asconf,
2431 * If an error response is received for a TLV parameter,
2432 * all TLVs with no response before the failed TLV are
2433 * considered successful if not reported. All TLVs after
2434 * the failed response are considered unsuccessful unless
2435 * a specific success indication is present for the parameter.
2437 if (SCTP_ERROR_NO_ERROR != err_code)
2440 if (!all_param_pass)
2441 sctp_add_asconf_response(asconf_ack,
2442 asconf_param->crr_id, err_code,
2445 /* ADDIP 4.3 D11) When an endpoint receiving an ASCONF to add
2446 * an IP address sends an 'Out of Resource' in its response, it
2447 * MUST also fail any subsequent add or delete requests bundled
2450 if (SCTP_ERROR_RSRC_LOW == err_code)
2453 /* Move to the next ASCONF param. */
2454 length = ntohs(asconf_param->param_hdr.length);
2455 asconf_param = (sctp_addip_param_t *)((void *)asconf_param +
2457 chunk_len -= length;
2461 asoc->peer.addip_serial++;
2463 /* If we are sending a new ASCONF_ACK hold a reference to it in assoc
2464 * after freeing the reference to old asconf ack if any.
2467 if (asoc->addip_last_asconf_ack)
2468 sctp_chunk_free(asoc->addip_last_asconf_ack);
2470 sctp_chunk_hold(asconf_ack);
2471 asoc->addip_last_asconf_ack = asconf_ack;
2477 /* Process a asconf parameter that is successfully acked. */
2478 static int sctp_asconf_param_success(struct sctp_association *asoc,
2479 sctp_addip_param_t *asconf_param)
2482 union sctp_addr addr;
2483 struct sctp_bind_addr *bp = &asoc->base.bind_addr;
2484 union sctp_addr_param *addr_param;
2485 struct list_head *pos;
2486 struct sctp_transport *transport;
2489 addr_param = (union sctp_addr_param *)
2490 ((void *)asconf_param + sizeof(sctp_addip_param_t));
2492 /* We have checked the packet before, so we do not check again. */
2493 af = sctp_get_af_specific(param_type2af(addr_param->v4.param_hdr.type));
2494 af->from_addr_param(&addr, addr_param, bp->port, 0);
2496 switch (asconf_param->param_hdr.type) {
2497 case SCTP_PARAM_ADD_IP:
2498 sctp_local_bh_disable();
2499 sctp_write_lock(&asoc->base.addr_lock);
2500 retval = sctp_add_bind_addr(bp, &addr, GFP_ATOMIC);
2501 sctp_write_unlock(&asoc->base.addr_lock);
2502 sctp_local_bh_enable();
2504 case SCTP_PARAM_DEL_IP:
2505 sctp_local_bh_disable();
2506 sctp_write_lock(&asoc->base.addr_lock);
2507 retval = sctp_del_bind_addr(bp, &addr);
2508 sctp_write_unlock(&asoc->base.addr_lock);
2509 sctp_local_bh_enable();
2510 list_for_each(pos, &asoc->peer.transport_addr_list) {
2511 transport = list_entry(pos, struct sctp_transport,
2513 sctp_transport_route(transport, NULL,
2514 sctp_sk(asoc->base.sk));
2524 /* Get the corresponding ASCONF response error code from the ASCONF_ACK chunk
2525 * for the given asconf parameter. If there is no response for this parameter,
2526 * return the error code based on the third argument 'no_err'.
2528 * A7) If an error response is received for a TLV parameter, all TLVs with no
2529 * response before the failed TLV are considered successful if not reported.
2530 * All TLVs after the failed response are considered unsuccessful unless a
2531 * specific success indication is present for the parameter.
2533 static __u16 sctp_get_asconf_response(struct sctp_chunk *asconf_ack,
2534 sctp_addip_param_t *asconf_param,
2537 sctp_addip_param_t *asconf_ack_param;
2538 sctp_errhdr_t *err_param;
2540 int asconf_ack_len = asconf_ack->skb->len;
2544 err_code = SCTP_ERROR_NO_ERROR;
2546 err_code = SCTP_ERROR_REQ_REFUSED;
2548 /* Skip the addiphdr from the asconf_ack chunk and store a pointer to
2549 * the first asconf_ack parameter.
2551 length = sizeof(sctp_addiphdr_t);
2552 asconf_ack_param = (sctp_addip_param_t *)(asconf_ack->skb->data +
2554 asconf_ack_len -= length;
2556 while (asconf_ack_len > 0) {
2557 if (asconf_ack_param->crr_id == asconf_param->crr_id) {
2558 switch(asconf_ack_param->param_hdr.type) {
2559 case SCTP_PARAM_SUCCESS_REPORT:
2560 return SCTP_ERROR_NO_ERROR;
2561 case SCTP_PARAM_ERR_CAUSE:
2562 length = sizeof(sctp_addip_param_t);
2563 err_param = (sctp_errhdr_t *)
2564 ((void *)asconf_ack_param + length);
2565 asconf_ack_len -= length;
2566 if (asconf_ack_len > 0)
2567 return err_param->cause;
2569 return SCTP_ERROR_INV_PARAM;
2572 return SCTP_ERROR_INV_PARAM;
2576 length = ntohs(asconf_ack_param->param_hdr.length);
2577 asconf_ack_param = (sctp_addip_param_t *)
2578 ((void *)asconf_ack_param + length);
2579 asconf_ack_len -= length;
2585 /* Process an incoming ASCONF_ACK chunk against the cached last ASCONF chunk. */
2586 int sctp_process_asconf_ack(struct sctp_association *asoc,
2587 struct sctp_chunk *asconf_ack)
2589 struct sctp_chunk *asconf = asoc->addip_last_asconf;
2590 union sctp_addr_param *addr_param;
2591 sctp_addip_param_t *asconf_param;
2593 int asconf_len = asconf->skb->len;
2594 int all_param_pass = 0;
2597 __u16 err_code = SCTP_ERROR_NO_ERROR;
2599 /* Skip the chunkhdr and addiphdr from the last asconf sent and store
2600 * a pointer to address parameter.
2602 length = sizeof(sctp_addip_chunk_t);
2603 addr_param = (union sctp_addr_param *)(asconf->skb->data + length);
2604 asconf_len -= length;
2606 /* Skip the address parameter in the last asconf sent and store a
2607 * pointer to the first asconf paramter.
2609 length = ntohs(addr_param->v4.param_hdr.length);
2610 asconf_param = (sctp_addip_param_t *)((void *)addr_param + length);
2611 asconf_len -= length;
2614 * A8) If there is no response(s) to specific TLV parameter(s), and no
2615 * failures are indicated, then all request(s) are considered
2618 if (asconf_ack->skb->len == sizeof(sctp_addiphdr_t))
2621 /* Process the TLVs contained in the last sent ASCONF chunk. */
2622 while (asconf_len > 0) {
2624 err_code = SCTP_ERROR_NO_ERROR;
2626 err_code = sctp_get_asconf_response(asconf_ack,
2629 if (no_err && (SCTP_ERROR_NO_ERROR != err_code))
2634 case SCTP_ERROR_NO_ERROR:
2635 retval = sctp_asconf_param_success(asoc, asconf_param);
2638 case SCTP_ERROR_RSRC_LOW:
2642 case SCTP_ERROR_INV_PARAM:
2643 /* Disable sending this type of asconf parameter in
2646 asoc->peer.addip_disabled_mask |=
2647 asconf_param->param_hdr.type;
2650 case SCTP_ERROR_REQ_REFUSED:
2651 case SCTP_ERROR_DEL_LAST_IP:
2652 case SCTP_ERROR_DEL_SRC_IP:
2657 /* Skip the processed asconf parameter and move to the next
2660 length = ntohs(asconf_param->param_hdr.length);
2661 asconf_param = (sctp_addip_param_t *)((void *)asconf_param +
2663 asconf_len -= length;
2666 /* Free the cached last sent asconf chunk. */
2667 sctp_chunk_free(asconf);
2668 asoc->addip_last_asconf = NULL;
2670 /* Send the next asconf chunk from the addip chunk queue. */
2671 asconf = (struct sctp_chunk *)__skb_dequeue(&asoc->addip_chunks);
2673 /* Hold the chunk until an ASCONF_ACK is received. */
2674 sctp_chunk_hold(asconf);
2675 if (sctp_primitive_ASCONF(asoc, asconf))
2676 sctp_chunk_free(asconf);
2678 asoc->addip_last_asconf = asconf;
2684 /* Make a FWD TSN chunk. */
2685 struct sctp_chunk *sctp_make_fwdtsn(const struct sctp_association *asoc,
2686 __u32 new_cum_tsn, size_t nstreams,
2687 struct sctp_fwdtsn_skip *skiplist)
2689 struct sctp_chunk *retval = NULL;
2690 struct sctp_fwdtsn_chunk *ftsn_chunk;
2691 struct sctp_fwdtsn_hdr ftsn_hdr;
2692 struct sctp_fwdtsn_skip skip;
2696 hint = (nstreams + 1) * sizeof(__u32);
2698 /* Maybe set the T-bit if we have no association. */
2699 retval = sctp_make_chunk(asoc, SCTP_CID_FWD_TSN, 0, hint);
2704 ftsn_chunk = (struct sctp_fwdtsn_chunk *)retval->subh.fwdtsn_hdr;
2706 ftsn_hdr.new_cum_tsn = htonl(new_cum_tsn);
2707 retval->subh.fwdtsn_hdr =
2708 sctp_addto_chunk(retval, sizeof(ftsn_hdr), &ftsn_hdr);
2710 for (i = 0; i < nstreams; i++) {
2711 skip.stream = skiplist[i].stream;
2712 skip.ssn = skiplist[i].ssn;
2713 sctp_addto_chunk(retval, sizeof(skip), &skip);