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;
175 /* RFC 2960 3.3.2 Initiation (INIT) (1)
177 * Note 1: The INIT chunks can contain multiple addresses that
178 * can be IPv4 and/or IPv6 in any combination.
182 /* Convert the provided bind address list to raw format. */
183 addrs = sctp_bind_addrs_to_raw(bp, &addrs_len, gfp);
185 init.init_tag = htonl(asoc->c.my_vtag);
186 init.a_rwnd = htonl(asoc->rwnd);
187 init.num_outbound_streams = htons(asoc->c.sinit_num_ostreams);
188 init.num_inbound_streams = htons(asoc->c.sinit_max_instreams);
189 init.initial_tsn = htonl(asoc->c.initial_tsn);
191 /* How many address types are needed? */
192 sp = sctp_sk(asoc->base.sk);
193 num_types = sp->pf->supported_addrs(sp, types);
195 chunksize = sizeof(init) + addrs_len + SCTP_SAT_LEN(num_types);
196 chunksize += sizeof(ecap_param);
197 if (sctp_prsctp_enable)
198 chunksize += sizeof(prsctp_param);
199 chunksize += vparam_len;
201 /* RFC 2960 3.3.2 Initiation (INIT) (1)
203 * Note 3: An INIT chunk MUST NOT contain more than one Host
204 * Name address parameter. Moreover, the sender of the INIT
205 * MUST NOT combine any other address types with the Host Name
206 * address in the INIT. The receiver of INIT MUST ignore any
207 * other address types if the Host Name address parameter is
208 * present in the received INIT chunk.
210 * PLEASE DO NOT FIXME [This version does not support Host Name.]
213 retval = sctp_make_chunk(asoc, SCTP_CID_INIT, 0, chunksize);
217 retval->subh.init_hdr =
218 sctp_addto_chunk(retval, sizeof(init), &init);
219 retval->param_hdr.v =
220 sctp_addto_chunk(retval, addrs_len, addrs.v);
222 /* RFC 2960 3.3.2 Initiation (INIT) (1)
224 * Note 4: This parameter, when present, specifies all the
225 * address types the sending endpoint can support. The absence
226 * of this parameter indicates that the sending endpoint can
227 * support any address type.
229 sat.param_hdr.type = SCTP_PARAM_SUPPORTED_ADDRESS_TYPES;
230 sat.param_hdr.length = htons(SCTP_SAT_LEN(num_types));
231 sctp_addto_chunk(retval, sizeof(sat), &sat);
232 sctp_addto_chunk(retval, num_types * sizeof(__u16), &types);
234 sctp_addto_chunk(retval, sizeof(ecap_param), &ecap_param);
235 if (sctp_prsctp_enable)
236 sctp_addto_chunk(retval, sizeof(prsctp_param), &prsctp_param);
243 struct sctp_chunk *sctp_make_init_ack(const struct sctp_association *asoc,
244 const struct sctp_chunk *chunk,
245 int gfp, int unkparam_len)
247 sctp_inithdr_t initack;
248 struct sctp_chunk *retval;
249 union sctp_params addrs;
251 sctp_cookie_param_t *cookie;
257 /* Note: there may be no addresses to embed. */
258 addrs = sctp_bind_addrs_to_raw(&asoc->base.bind_addr, &addrs_len, gfp);
260 initack.init_tag = htonl(asoc->c.my_vtag);
261 initack.a_rwnd = htonl(asoc->rwnd);
262 initack.num_outbound_streams = htons(asoc->c.sinit_num_ostreams);
263 initack.num_inbound_streams = htons(asoc->c.sinit_max_instreams);
264 initack.initial_tsn = htonl(asoc->c.initial_tsn);
266 /* FIXME: We really ought to build the cookie right
267 * into the packet instead of allocating more fresh memory.
269 cookie = sctp_pack_cookie(asoc->ep, asoc, chunk, &cookie_len,
274 /* Calculate the total size of allocation, include the reserved
275 * space for reporting unknown parameters if it is specified.
277 chunksize = sizeof(initack) + addrs_len + cookie_len + unkparam_len;
279 /* Tell peer that we'll do ECN only if peer advertised such cap. */
280 if (asoc->peer.ecn_capable)
281 chunksize += sizeof(ecap_param);
283 /* Tell peer that we'll do PR-SCTP only if peer advertised. */
284 if (asoc->peer.prsctp_capable)
285 chunksize += sizeof(prsctp_param);
287 /* Now allocate and fill out the chunk. */
288 retval = sctp_make_chunk(asoc, SCTP_CID_INIT_ACK, 0, chunksize);
292 /* Per the advice in RFC 2960 6.4, send this reply to
293 * the source of the INIT packet.
295 retval->transport = chunk->transport;
296 retval->subh.init_hdr =
297 sctp_addto_chunk(retval, sizeof(initack), &initack);
298 retval->param_hdr.v = sctp_addto_chunk(retval, addrs_len, addrs.v);
299 sctp_addto_chunk(retval, cookie_len, cookie);
300 if (asoc->peer.ecn_capable)
301 sctp_addto_chunk(retval, sizeof(ecap_param), &ecap_param);
302 if (asoc->peer.prsctp_capable)
303 sctp_addto_chunk(retval, sizeof(prsctp_param), &prsctp_param);
305 /* We need to remove the const qualifier at this point. */
306 retval->asoc = (struct sctp_association *) asoc;
308 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
310 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
311 * HEARTBEAT ACK, * etc.) to the same destination transport
312 * address from which it received the DATA or control chunk
313 * to which it is replying.
315 * [INIT ACK back to where the INIT came from.]
318 retval->transport = chunk->transport;
328 /* 3.3.11 Cookie Echo (COOKIE ECHO) (10):
330 * This chunk is used only during the initialization of an association.
331 * It is sent by the initiator of an association to its peer to complete
332 * the initialization process. This chunk MUST precede any DATA chunk
333 * sent within the association, but MAY be bundled with one or more DATA
334 * chunks in the same packet.
337 * 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
338 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
339 * | Type = 10 |Chunk Flags | Length |
340 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
343 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
347 * Set to zero on transmit and ignored on receipt.
349 * Length: 16 bits (unsigned integer)
351 * Set to the size of the chunk in bytes, including the 4 bytes of
352 * the chunk header and the size of the Cookie.
354 * Cookie: variable size
356 * This field must contain the exact cookie received in the
357 * State Cookie parameter from the previous INIT ACK.
359 * An implementation SHOULD make the cookie as small as possible
360 * to insure interoperability.
362 struct sctp_chunk *sctp_make_cookie_echo(const struct sctp_association *asoc,
363 const struct sctp_chunk *chunk)
365 struct sctp_chunk *retval;
369 cookie = asoc->peer.cookie;
370 cookie_len = asoc->peer.cookie_len;
372 /* Build a cookie echo chunk. */
373 retval = sctp_make_chunk(asoc, SCTP_CID_COOKIE_ECHO, 0, cookie_len);
376 retval->subh.cookie_hdr =
377 sctp_addto_chunk(retval, cookie_len, cookie);
379 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
381 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
382 * HEARTBEAT ACK, * etc.) to the same destination transport
383 * address from which it * received the DATA or control chunk
384 * to which it is replying.
386 * [COOKIE ECHO back to where the INIT ACK came from.]
389 retval->transport = chunk->transport;
395 /* 3.3.12 Cookie Acknowledgement (COOKIE ACK) (11):
397 * This chunk is used only during the initialization of an
398 * association. It is used to acknowledge the receipt of a COOKIE
399 * ECHO chunk. This chunk MUST precede any DATA or SACK chunk sent
400 * within the association, but MAY be bundled with one or more DATA
401 * chunks or SACK chunk in the same SCTP packet.
404 * 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
405 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
406 * | Type = 11 |Chunk Flags | Length = 4 |
407 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
409 * Chunk Flags: 8 bits
411 * Set to zero on transmit and ignored on receipt.
413 struct sctp_chunk *sctp_make_cookie_ack(const struct sctp_association *asoc,
414 const struct sctp_chunk *chunk)
416 struct sctp_chunk *retval;
418 retval = sctp_make_chunk(asoc, SCTP_CID_COOKIE_ACK, 0, 0);
420 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
422 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
423 * HEARTBEAT ACK, * etc.) to the same destination transport
424 * address from which it * received the DATA or control chunk
425 * to which it is replying.
427 * [COOKIE ACK back to where the COOKIE ECHO came from.]
430 retval->transport = chunk->transport;
436 * Appendix A: Explicit Congestion Notification:
439 * RFC 2481 details a specific bit for a sender to send in the header of
440 * its next outbound TCP segment to indicate to its peer that it has
441 * reduced its congestion window. This is termed the CWR bit. For
442 * SCTP the same indication is made by including the CWR chunk.
443 * This chunk contains one data element, i.e. the TSN number that
444 * was sent in the ECNE chunk. This element represents the lowest
445 * TSN number in the datagram that was originally marked with the
449 * 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
450 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
451 * | Chunk Type=13 | Flags=00000000| Chunk Length = 8 |
452 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
453 * | Lowest TSN Number |
454 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
456 * Note: The CWR is considered a Control chunk.
458 struct sctp_chunk *sctp_make_cwr(const struct sctp_association *asoc,
459 const __u32 lowest_tsn,
460 const struct sctp_chunk *chunk)
462 struct sctp_chunk *retval;
465 cwr.lowest_tsn = htonl(lowest_tsn);
466 retval = sctp_make_chunk(asoc, SCTP_CID_ECN_CWR, 0,
467 sizeof(sctp_cwrhdr_t));
472 retval->subh.ecn_cwr_hdr =
473 sctp_addto_chunk(retval, sizeof(cwr), &cwr);
475 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
477 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
478 * HEARTBEAT ACK, * etc.) to the same destination transport
479 * address from which it * received the DATA or control chunk
480 * to which it is replying.
482 * [Report a reduced congestion window back to where the ECNE
486 retval->transport = chunk->transport;
492 /* Make an ECNE chunk. This is a congestion experienced report. */
493 struct sctp_chunk *sctp_make_ecne(const struct sctp_association *asoc,
494 const __u32 lowest_tsn)
496 struct sctp_chunk *retval;
499 ecne.lowest_tsn = htonl(lowest_tsn);
500 retval = sctp_make_chunk(asoc, SCTP_CID_ECN_ECNE, 0,
501 sizeof(sctp_ecnehdr_t));
504 retval->subh.ecne_hdr =
505 sctp_addto_chunk(retval, sizeof(ecne), &ecne);
511 /* Make a DATA chunk for the given association from the provided
512 * parameters. However, do not populate the data payload.
514 struct sctp_chunk *sctp_make_datafrag_empty(struct sctp_association *asoc,
515 const struct sctp_sndrcvinfo *sinfo,
516 int data_len, __u8 flags, __u16 ssn)
518 struct sctp_chunk *retval;
519 struct sctp_datahdr dp;
522 /* We assign the TSN as LATE as possible, not here when
523 * creating the chunk.
526 dp.stream = htons(sinfo->sinfo_stream);
527 dp.ppid = sinfo->sinfo_ppid;
529 /* Set the flags for an unordered send. */
530 if (sinfo->sinfo_flags & MSG_UNORDERED) {
531 flags |= SCTP_DATA_UNORDERED;
536 chunk_len = sizeof(dp) + data_len;
537 retval = sctp_make_chunk(asoc, SCTP_CID_DATA, flags, chunk_len);
541 retval->subh.data_hdr = sctp_addto_chunk(retval, sizeof(dp), &dp);
542 memcpy(&retval->sinfo, sinfo, sizeof(struct sctp_sndrcvinfo));
548 /* Make a DATA chunk for the given association. Populate the data
551 struct sctp_chunk *sctp_make_datafrag(struct sctp_association *asoc,
552 const struct sctp_sndrcvinfo *sinfo,
553 int data_len, const __u8 *data,
554 __u8 flags, __u16 ssn)
556 struct sctp_chunk *retval;
558 retval = sctp_make_datafrag_empty(asoc, sinfo, data_len, flags, ssn);
560 sctp_addto_chunk(retval, data_len, data);
565 /* Make a DATA chunk for the given association to ride on stream id
566 * 'stream', with a payload id of 'payload', and a body of 'data'.
568 struct sctp_chunk *sctp_make_data(struct sctp_association *asoc,
569 const struct sctp_sndrcvinfo *sinfo,
570 int data_len, const __u8 *data)
572 struct sctp_chunk *retval = NULL;
574 retval = sctp_make_data_empty(asoc, sinfo, data_len);
576 sctp_addto_chunk(retval, data_len, data);
580 /* Make a DATA chunk for the given association to ride on stream id
581 * 'stream', with a payload id of 'payload', and a body big enough to
582 * hold 'data_len' octets of data. We use this version when we need
583 * to build the message AFTER allocating memory.
585 struct sctp_chunk *sctp_make_data_empty(struct sctp_association *asoc,
586 const struct sctp_sndrcvinfo *sinfo,
589 __u8 flags = SCTP_DATA_NOT_FRAG;
591 return sctp_make_datafrag_empty(asoc, sinfo, data_len, flags, 0);
594 /* Create a selective ackowledgement (SACK) for the given
595 * association. This reports on which TSN's we've seen to date,
596 * including duplicates and gaps.
598 struct sctp_chunk *sctp_make_sack(const struct sctp_association *asoc)
600 struct sctp_chunk *retval;
601 struct sctp_sackhdr sack;
604 __u16 num_gabs, num_dup_tsns;
605 struct sctp_tsnmap *map = (struct sctp_tsnmap *)&asoc->peer.tsn_map;
607 ctsn = sctp_tsnmap_get_ctsn(map);
608 SCTP_DEBUG_PRINTK("sackCTSNAck sent: 0x%x.\n", ctsn);
610 /* How much room is needed in the chunk? */
611 num_gabs = sctp_tsnmap_num_gabs(map);
612 num_dup_tsns = sctp_tsnmap_num_dups(map);
614 /* Initialize the SACK header. */
615 sack.cum_tsn_ack = htonl(ctsn);
616 sack.a_rwnd = htonl(asoc->a_rwnd);
617 sack.num_gap_ack_blocks = htons(num_gabs);
618 sack.num_dup_tsns = htons(num_dup_tsns);
621 + sizeof(struct sctp_gap_ack_block) * num_gabs
622 + sizeof(__u32) * num_dup_tsns;
624 /* Create the chunk. */
625 retval = sctp_make_chunk(asoc, SCTP_CID_SACK, 0, len);
629 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
631 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
632 * HEARTBEAT ACK, etc.) to the same destination transport
633 * address from which it received the DATA or control chunk to
634 * which it is replying. This rule should also be followed if
635 * the endpoint is bundling DATA chunks together with the
638 * However, when acknowledging multiple DATA chunks received
639 * in packets from different source addresses in a single
640 * SACK, the SACK chunk may be transmitted to one of the
641 * destination transport addresses from which the DATA or
642 * control chunks being acknowledged were received.
644 * [BUG: We do not implement the following paragraph.
645 * Perhaps we should remember the last transport we used for a
646 * SACK and avoid that (if possible) if we have seen any
647 * duplicates. --piggy]
649 * When a receiver of a duplicate DATA chunk sends a SACK to a
650 * multi- homed endpoint it MAY be beneficial to vary the
651 * destination address and not use the source address of the
652 * DATA chunk. The reason being that receiving a duplicate
653 * from a multi-homed endpoint might indicate that the return
654 * path (as specified in the source address of the DATA chunk)
655 * for the SACK is broken.
657 * [Send to the address from which we last received a DATA chunk.]
659 retval->transport = asoc->peer.last_data_from;
661 retval->subh.sack_hdr =
662 sctp_addto_chunk(retval, sizeof(sack), &sack);
664 /* Add the gap ack block information. */
666 sctp_addto_chunk(retval, sizeof(__u32) * num_gabs,
667 sctp_tsnmap_get_gabs(map));
669 /* Add the duplicate TSN information. */
671 sctp_addto_chunk(retval, sizeof(__u32) * num_dup_tsns,
672 sctp_tsnmap_get_dups(map));
678 /* Make a SHUTDOWN chunk. */
679 struct sctp_chunk *sctp_make_shutdown(const struct sctp_association *asoc,
680 const struct sctp_chunk *chunk)
682 struct sctp_chunk *retval;
683 sctp_shutdownhdr_t shut;
686 ctsn = sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map);
687 shut.cum_tsn_ack = htonl(ctsn);
689 retval = sctp_make_chunk(asoc, SCTP_CID_SHUTDOWN, 0,
690 sizeof(sctp_shutdownhdr_t));
694 retval->subh.shutdown_hdr =
695 sctp_addto_chunk(retval, sizeof(shut), &shut);
698 retval->transport = chunk->transport;
703 struct sctp_chunk *sctp_make_shutdown_ack(const struct sctp_association *asoc,
704 const struct sctp_chunk *chunk)
706 struct sctp_chunk *retval;
708 retval = sctp_make_chunk(asoc, SCTP_CID_SHUTDOWN_ACK, 0, 0);
710 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
712 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
713 * HEARTBEAT ACK, * etc.) to the same destination transport
714 * address from which it * received the DATA or control chunk
715 * to which it is replying.
717 * [ACK back to where the SHUTDOWN came from.]
720 retval->transport = chunk->transport;
725 struct sctp_chunk *sctp_make_shutdown_complete(
726 const struct sctp_association *asoc,
727 const struct sctp_chunk *chunk)
729 struct sctp_chunk *retval;
732 /* Maybe set the T-bit if we have no association. */
733 flags |= asoc ? 0 : SCTP_CHUNK_FLAG_T;
735 retval = sctp_make_chunk(asoc, SCTP_CID_SHUTDOWN_COMPLETE, flags, 0);
737 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
739 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
740 * HEARTBEAT ACK, * etc.) to the same destination transport
741 * address from which it * received the DATA or control chunk
742 * to which it is replying.
744 * [Report SHUTDOWN COMPLETE back to where the SHUTDOWN ACK
748 retval->transport = chunk->transport;
753 /* Create an ABORT. Note that we set the T bit if we have no
756 struct sctp_chunk *sctp_make_abort(const struct sctp_association *asoc,
757 const struct sctp_chunk *chunk,
760 struct sctp_chunk *retval;
763 /* Maybe set the T-bit if we have no association. */
764 flags |= asoc ? 0 : SCTP_CHUNK_FLAG_T;
766 retval = sctp_make_chunk(asoc, SCTP_CID_ABORT, flags, hint);
768 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
770 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
771 * HEARTBEAT ACK, * etc.) to the same destination transport
772 * address from which it * received the DATA or control chunk
773 * to which it is replying.
775 * [ABORT back to where the offender came from.]
778 retval->transport = chunk->transport;
783 /* Helper to create ABORT with a NO_USER_DATA error. */
784 struct sctp_chunk *sctp_make_abort_no_data(
785 const struct sctp_association *asoc,
786 const struct sctp_chunk *chunk, __u32 tsn)
788 struct sctp_chunk *retval;
791 retval = sctp_make_abort(asoc, chunk, sizeof(sctp_errhdr_t)
797 /* Put the tsn back into network byte order. */
798 payload = htonl(tsn);
799 sctp_init_cause(retval, SCTP_ERROR_NO_DATA, (const void *)&payload,
802 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
804 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
805 * HEARTBEAT ACK, * etc.) to the same destination transport
806 * address from which it * received the DATA or control chunk
807 * to which it is replying.
809 * [ABORT back to where the offender came from.]
812 retval->transport = chunk->transport;
818 /* Helper to create ABORT with a SCTP_ERROR_USER_ABORT error. */
819 struct sctp_chunk *sctp_make_abort_user(const struct sctp_association *asoc,
820 const struct sctp_chunk *chunk,
821 const struct msghdr *msg)
823 struct sctp_chunk *retval;
824 void *payload = NULL, *payoff;
826 struct iovec *iov = NULL;
831 iovlen = msg->msg_iovlen;
832 paylen = get_user_iov_size(iov, iovlen);
835 retval = sctp_make_abort(asoc, chunk, sizeof(sctp_errhdr_t) + paylen);
840 /* Put the msg_iov together into payload. */
841 payload = kmalloc(paylen, GFP_ATOMIC);
846 for (; iovlen > 0; --iovlen) {
847 if (copy_from_user(payoff, iov->iov_base,iov->iov_len))
849 payoff += iov->iov_len;
854 sctp_init_cause(retval, SCTP_ERROR_USER_ABORT, payload, paylen);
864 sctp_chunk_free(retval);
870 /* Make a HEARTBEAT chunk. */
871 struct sctp_chunk *sctp_make_heartbeat(const struct sctp_association *asoc,
872 const struct sctp_transport *transport,
873 const void *payload, const size_t paylen)
875 struct sctp_chunk *retval = sctp_make_chunk(asoc, SCTP_CID_HEARTBEAT,
881 /* Cast away the 'const', as this is just telling the chunk
882 * what transport it belongs to.
884 retval->transport = (struct sctp_transport *) transport;
885 retval->subh.hbs_hdr = sctp_addto_chunk(retval, paylen, payload);
891 struct sctp_chunk *sctp_make_heartbeat_ack(const struct sctp_association *asoc,
892 const struct sctp_chunk *chunk,
893 const void *payload, const size_t paylen)
895 struct sctp_chunk *retval;
897 retval = sctp_make_chunk(asoc, SCTP_CID_HEARTBEAT_ACK, 0, paylen);
901 retval->subh.hbs_hdr = sctp_addto_chunk(retval, paylen, payload);
903 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
905 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
906 * HEARTBEAT ACK, * etc.) to the same destination transport
907 * address from which it * received the DATA or control chunk
908 * to which it is replying.
910 * [HBACK back to where the HEARTBEAT came from.]
913 retval->transport = chunk->transport;
919 /* Create an Operation Error chunk with the specified space reserved.
920 * This routine can be used for containing multiple causes in the chunk.
922 struct sctp_chunk *sctp_make_op_error_space(
923 const struct sctp_association *asoc,
924 const struct sctp_chunk *chunk,
927 struct sctp_chunk *retval;
929 retval = sctp_make_chunk(asoc, SCTP_CID_ERROR, 0,
930 sizeof(sctp_errhdr_t) + size);
934 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
936 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
937 * HEARTBEAT ACK, etc.) to the same destination transport
938 * address from which it received the DATA or control chunk
939 * to which it is replying.
943 retval->transport = chunk->transport;
949 /* Create an Operation Error chunk. */
950 struct sctp_chunk *sctp_make_op_error(const struct sctp_association *asoc,
951 const struct sctp_chunk *chunk,
952 __u16 cause_code, const void *payload,
955 struct sctp_chunk *retval;
957 retval = sctp_make_op_error_space(asoc, chunk, paylen);
961 sctp_init_cause(retval, cause_code, payload, paylen);
967 /********************************************************************
968 * 2nd Level Abstractions
969 ********************************************************************/
971 /* Turn an skb into a chunk.
972 * FIXME: Eventually move the structure directly inside the skb->cb[].
974 struct sctp_chunk *sctp_chunkify(struct sk_buff *skb,
975 const struct sctp_association *asoc,
978 struct sctp_chunk *retval;
980 retval = kmem_cache_alloc(sctp_chunk_cachep, SLAB_ATOMIC);
984 memset(retval, 0, sizeof(struct sctp_chunk));
987 SCTP_DEBUG_PRINTK("chunkifying skb %p w/o an sk\n", skb);
991 retval->asoc = (struct sctp_association *)asoc;
995 retval->rtt_in_progress = 0;
997 retval->singleton = 1;
998 retval->end_of_packet = 0;
999 retval->ecn_ce_done = 0;
1000 retval->pdiscard = 0;
1002 /* sctpimpguide-05.txt Section 2.8.2
1003 * M1) Each time a new DATA chunk is transmitted
1004 * set the 'TSN.Missing.Report' count for that TSN to 0. The
1005 * 'TSN.Missing.Report' count will be used to determine missing chunks
1006 * and when to fast retransmit.
1008 retval->tsn_missing_report = 0;
1009 retval->tsn_gap_acked = 0;
1010 retval->fast_retransmit = 0;
1012 /* If this is a fragmented message, track all fragments
1013 * of the message (for SEND_FAILED).
1017 /* Polish the bead hole. */
1018 INIT_LIST_HEAD(&retval->transmitted_list);
1019 INIT_LIST_HEAD(&retval->frag_list);
1020 SCTP_DBG_OBJCNT_INC(chunk);
1021 atomic_set(&retval->refcnt, 1);
1028 /* Set chunk->source and dest based on the IP header in chunk->skb. */
1029 void sctp_init_addrs(struct sctp_chunk *chunk, union sctp_addr *src,
1030 union sctp_addr *dest)
1032 memcpy(&chunk->source, src, sizeof(union sctp_addr));
1033 memcpy(&chunk->dest, dest, sizeof(union sctp_addr));
1036 /* Extract the source address from a chunk. */
1037 const union sctp_addr *sctp_source(const struct sctp_chunk *chunk)
1039 /* If we have a known transport, use that. */
1040 if (chunk->transport) {
1041 return &chunk->transport->ipaddr;
1043 /* Otherwise, extract it from the IP header. */
1044 return &chunk->source;
1048 /* Create a new chunk, setting the type and flags headers from the
1049 * arguments, reserving enough space for a 'paylen' byte payload.
1051 struct sctp_chunk *sctp_make_chunk(const struct sctp_association *asoc,
1052 __u8 type, __u8 flags, int paylen)
1054 struct sctp_chunk *retval;
1055 sctp_chunkhdr_t *chunk_hdr;
1056 struct sk_buff *skb;
1059 /* No need to allocate LL here, as this is only a chunk. */
1060 skb = alloc_skb(WORD_ROUND(sizeof(sctp_chunkhdr_t) + paylen),
1065 /* Make room for the chunk header. */
1066 chunk_hdr = (sctp_chunkhdr_t *)skb_put(skb, sizeof(sctp_chunkhdr_t));
1067 chunk_hdr->type = type;
1068 chunk_hdr->flags = flags;
1069 chunk_hdr->length = htons(sizeof(sctp_chunkhdr_t));
1071 sk = asoc ? asoc->base.sk : NULL;
1072 retval = sctp_chunkify(skb, asoc, sk);
1078 retval->chunk_hdr = chunk_hdr;
1079 retval->chunk_end = ((__u8 *)chunk_hdr) + sizeof(struct sctp_chunkhdr);
1081 /* Set the skb to the belonging sock for accounting. */
1090 /* Release the memory occupied by a chunk. */
1091 static void sctp_chunk_destroy(struct sctp_chunk *chunk)
1093 /* Free the chunk skb data and the SCTP_chunk stub itself. */
1094 dev_kfree_skb(chunk->skb);
1096 SCTP_DBG_OBJCNT_DEC(chunk);
1097 kmem_cache_free(sctp_chunk_cachep, chunk);
1100 /* Possibly, free the chunk. */
1101 void sctp_chunk_free(struct sctp_chunk *chunk)
1103 /* Make sure that we are not on any list. */
1104 skb_unlink((struct sk_buff *) chunk);
1105 list_del_init(&chunk->transmitted_list);
1107 /* Release our reference on the message tracker. */
1109 sctp_datamsg_put(chunk->msg);
1111 sctp_chunk_put(chunk);
1114 /* Grab a reference to the chunk. */
1115 void sctp_chunk_hold(struct sctp_chunk *ch)
1117 atomic_inc(&ch->refcnt);
1120 /* Release a reference to the chunk. */
1121 void sctp_chunk_put(struct sctp_chunk *ch)
1123 if (atomic_dec_and_test(&ch->refcnt))
1124 sctp_chunk_destroy(ch);
1127 /* Append bytes to the end of a chunk. Will panic if chunk is not big
1130 void *sctp_addto_chunk(struct sctp_chunk *chunk, int len, const void *data)
1134 int chunklen = ntohs(chunk->chunk_hdr->length);
1135 int padlen = chunklen % 4;
1137 padding = skb_put(chunk->skb, padlen);
1138 target = skb_put(chunk->skb, len);
1140 memset(padding, 0, padlen);
1141 memcpy(target, data, len);
1143 /* Adjust the chunk length field. */
1144 chunk->chunk_hdr->length = htons(chunklen + padlen + len);
1145 chunk->chunk_end = chunk->skb->tail;
1150 /* Append bytes from user space to the end of a chunk. Will panic if
1151 * chunk is not big enough.
1152 * Returns a kernel err value.
1154 int sctp_user_addto_chunk(struct sctp_chunk *chunk, int off, int len,
1160 /* Make room in chunk for data. */
1161 target = skb_put(chunk->skb, len);
1163 /* Copy data (whole iovec) into chunk */
1164 if ((err = memcpy_fromiovecend(target, data, off, len)))
1167 /* Adjust the chunk length field. */
1168 chunk->chunk_hdr->length =
1169 htons(ntohs(chunk->chunk_hdr->length) + len);
1170 chunk->chunk_end = chunk->skb->tail;
1176 /* Helper function to assign a TSN if needed. This assumes that both
1177 * the data_hdr and association have already been assigned.
1179 void sctp_chunk_assign_ssn(struct sctp_chunk *chunk)
1187 /* This is the last possible instant to assign a SSN. */
1188 if (chunk->chunk_hdr->flags & SCTP_DATA_UNORDERED) {
1191 sid = htons(chunk->subh.data_hdr->stream);
1192 if (chunk->chunk_hdr->flags & SCTP_DATA_LAST_FRAG)
1193 ssn = sctp_ssn_next(&chunk->asoc->ssnmap->out, sid);
1195 ssn = sctp_ssn_peek(&chunk->asoc->ssnmap->out, sid);
1199 chunk->subh.data_hdr->ssn = ssn;
1203 /* Helper function to assign a TSN if needed. This assumes that both
1204 * the data_hdr and association have already been assigned.
1206 void sctp_chunk_assign_tsn(struct sctp_chunk *chunk)
1208 if (!chunk->has_tsn) {
1209 /* This is the last possible instant to
1212 chunk->subh.data_hdr->tsn =
1213 htonl(sctp_association_get_next_tsn(chunk->asoc));
1218 /* Create a CLOSED association to use with an incoming packet. */
1219 struct sctp_association *sctp_make_temp_asoc(const struct sctp_endpoint *ep,
1220 struct sctp_chunk *chunk, int gfp)
1222 struct sctp_association *asoc;
1223 struct sk_buff *skb;
1227 /* Create the bare association. */
1228 scope = sctp_scope(sctp_source(chunk));
1229 asoc = sctp_association_new(ep, ep->base.sk, scope, gfp);
1234 /* Create an entry for the source address of the packet. */
1235 af = sctp_get_af_specific(ipver2af(skb->nh.iph->version));
1238 af->from_skb(&asoc->c.peer_addr, skb, 1);
1243 sctp_association_free(asoc);
1247 /* Build a cookie representing asoc.
1248 * This INCLUDES the param header needed to put the cookie in the INIT ACK.
1250 sctp_cookie_param_t *sctp_pack_cookie(const struct sctp_endpoint *ep,
1251 const struct sctp_association *asoc,
1252 const struct sctp_chunk *init_chunk,
1254 const __u8 *raw_addrs, int addrs_len)
1256 sctp_cookie_param_t *retval;
1257 struct sctp_signed_cookie *cookie;
1258 struct scatterlist sg;
1259 int headersize, bodysize;
1260 unsigned int keylen;
1263 headersize = sizeof(sctp_paramhdr_t) + SCTP_SECRET_SIZE;
1264 bodysize = sizeof(struct sctp_cookie)
1265 + ntohs(init_chunk->chunk_hdr->length) + addrs_len;
1267 /* Pad out the cookie to a multiple to make the signature
1268 * functions simpler to write.
1270 if (bodysize % SCTP_COOKIE_MULTIPLE)
1271 bodysize += SCTP_COOKIE_MULTIPLE
1272 - (bodysize % SCTP_COOKIE_MULTIPLE);
1273 *cookie_len = headersize + bodysize;
1275 retval = (sctp_cookie_param_t *)kmalloc(*cookie_len, GFP_ATOMIC);
1282 /* Clear this memory since we are sending this data structure
1283 * out on the network.
1285 memset(retval, 0x00, *cookie_len);
1286 cookie = (struct sctp_signed_cookie *) retval->body;
1288 /* Set up the parameter header. */
1289 retval->p.type = SCTP_PARAM_STATE_COOKIE;
1290 retval->p.length = htons(*cookie_len);
1292 /* Copy the cookie part of the association itself. */
1293 cookie->c = asoc->c;
1294 /* Save the raw address list length in the cookie. */
1295 cookie->c.raw_addr_list_len = addrs_len;
1297 /* Remember PR-SCTP capability. */
1298 cookie->c.prsctp_capable = asoc->peer.prsctp_capable;
1300 /* Set an expiration time for the cookie. */
1301 do_gettimeofday(&cookie->c.expiration);
1302 TIMEVAL_ADD(asoc->cookie_life, cookie->c.expiration);
1304 /* Copy the peer's init packet. */
1305 memcpy(&cookie->c.peer_init[0], init_chunk->chunk_hdr,
1306 ntohs(init_chunk->chunk_hdr->length));
1308 /* Copy the raw local address list of the association. */
1309 memcpy((__u8 *)&cookie->c.peer_init[0] +
1310 ntohs(init_chunk->chunk_hdr->length), raw_addrs, addrs_len);
1312 if (sctp_sk(ep->base.sk)->hmac) {
1313 /* Sign the message. */
1314 sg.page = virt_to_page(&cookie->c);
1315 sg.offset = (unsigned long)(&cookie->c) % PAGE_SIZE;
1316 sg.length = bodysize;
1317 keylen = SCTP_SECRET_SIZE;
1318 key = (char *)ep->secret_key[ep->current_key];
1320 sctp_crypto_hmac(sctp_sk(ep->base.sk)->hmac, key, &keylen,
1321 &sg, 1, cookie->signature);
1328 /* Unpack the cookie from COOKIE ECHO chunk, recreating the association. */
1329 struct sctp_association *sctp_unpack_cookie(
1330 const struct sctp_endpoint *ep,
1331 const struct sctp_association *asoc,
1332 struct sctp_chunk *chunk, int gfp,
1333 int *error, struct sctp_chunk **errp)
1335 struct sctp_association *retval = NULL;
1336 struct sctp_signed_cookie *cookie;
1337 struct sctp_cookie *bear_cookie;
1338 int headersize, bodysize, fixed_size;
1339 __u8 digest[SCTP_SIGNATURE_SIZE];
1340 struct scatterlist sg;
1341 unsigned int keylen, len;
1344 struct sk_buff *skb = chunk->skb;
1346 headersize = sizeof(sctp_chunkhdr_t) + SCTP_SECRET_SIZE;
1347 bodysize = ntohs(chunk->chunk_hdr->length) - headersize;
1348 fixed_size = headersize + sizeof(struct sctp_cookie);
1350 /* Verify that the chunk looks like it even has a cookie.
1351 * There must be enough room for our cookie and our peer's
1354 len = ntohs(chunk->chunk_hdr->length);
1355 if (len < fixed_size + sizeof(struct sctp_chunkhdr))
1358 /* Verify that the cookie has been padded out. */
1359 if (bodysize % SCTP_COOKIE_MULTIPLE)
1362 /* Process the cookie. */
1363 cookie = chunk->subh.cookie_hdr;
1364 bear_cookie = &cookie->c;
1366 if (!sctp_sk(ep->base.sk)->hmac)
1369 /* Check the signature. */
1370 keylen = SCTP_SECRET_SIZE;
1371 sg.page = virt_to_page(bear_cookie);
1372 sg.offset = (unsigned long)(bear_cookie) % PAGE_SIZE;
1373 sg.length = bodysize;
1374 key = (char *)ep->secret_key[ep->current_key];
1376 memset(digest, 0x00, sizeof(digest));
1377 sctp_crypto_hmac(sctp_sk(ep->base.sk)->hmac, key, &keylen, &sg,
1380 if (memcmp(digest, cookie->signature, SCTP_SIGNATURE_SIZE)) {
1381 /* Try the previous key. */
1382 key = (char *)ep->secret_key[ep->last_key];
1383 memset(digest, 0x00, sizeof(digest));
1384 sctp_crypto_hmac(sctp_sk(ep->base.sk)->hmac, key, &keylen,
1387 if (memcmp(digest, cookie->signature, SCTP_SIGNATURE_SIZE)) {
1388 /* Yikes! Still bad signature! */
1389 *error = -SCTP_IERROR_BAD_SIG;
1395 /* Check to see if the cookie is stale. If there is already
1396 * an association, there is no need to check cookie's expiration
1397 * for init collision case of lost COOKIE ACK.
1399 if (!asoc && tv_lt(bear_cookie->expiration, skb->stamp)) {
1402 * Section 3.3.10.3 Stale Cookie Error (3)
1406 * Stale Cookie Error: Indicates the receipt of a valid State
1407 * Cookie that has expired.
1409 len = ntohs(chunk->chunk_hdr->length);
1410 *errp = sctp_make_op_error_space(asoc, chunk, len);
1412 suseconds_t usecs = (skb->stamp.tv_sec -
1413 bear_cookie->expiration.tv_sec) * 1000000L +
1414 skb->stamp.tv_usec -
1415 bear_cookie->expiration.tv_usec;
1417 usecs = htonl(usecs);
1418 sctp_init_cause(*errp, SCTP_ERROR_STALE_COOKIE,
1419 &usecs, sizeof(usecs));
1420 *error = -SCTP_IERROR_STALE_COOKIE;
1422 *error = -SCTP_IERROR_NOMEM;
1427 /* Make a new base association. */
1428 scope = sctp_scope(sctp_source(chunk));
1429 retval = sctp_association_new(ep, ep->base.sk, scope, gfp);
1431 *error = -SCTP_IERROR_NOMEM;
1435 /* Set up our peer's port number. */
1436 retval->peer.port = ntohs(chunk->sctp_hdr->source);
1438 /* Populate the association from the cookie. */
1439 memcpy(&retval->c, bear_cookie, sizeof(*bear_cookie));
1441 if (sctp_assoc_set_bind_addr_from_cookie(retval, bear_cookie,
1443 *error = -SCTP_IERROR_NOMEM;
1447 /* Also, add the destination address. */
1448 if (list_empty(&retval->base.bind_addr.address_list)) {
1449 sctp_add_bind_addr(&retval->base.bind_addr, &chunk->dest,
1453 retval->next_tsn = retval->c.initial_tsn;
1454 retval->ctsn_ack_point = retval->next_tsn - 1;
1455 retval->addip_serial = retval->c.initial_tsn;
1456 retval->adv_peer_ack_point = retval->ctsn_ack_point;
1457 retval->peer.prsctp_capable = retval->c.prsctp_capable;
1459 /* The INIT stuff will be done by the side effects. */
1464 sctp_association_free(retval);
1469 /* Yikes! The packet is either corrupt or deliberately
1472 *error = -SCTP_IERROR_MALFORMED;
1476 /********************************************************************
1477 * 3rd Level Abstractions
1478 ********************************************************************/
1480 struct __sctp_missing {
1483 } __attribute__((packed));
1486 * Report a missing mandatory parameter.
1488 static int sctp_process_missing_param(const struct sctp_association *asoc,
1489 sctp_param_t paramtype,
1490 struct sctp_chunk *chunk,
1491 struct sctp_chunk **errp)
1493 struct __sctp_missing report;
1496 len = WORD_ROUND(sizeof(report));
1498 /* Make an ERROR chunk, preparing enough room for
1499 * returning multiple unknown parameters.
1502 *errp = sctp_make_op_error_space(asoc, chunk, len);
1505 report.num_missing = htonl(1);
1506 report.type = paramtype;
1507 sctp_init_cause(*errp, SCTP_ERROR_INV_PARAM,
1508 &report, sizeof(report));
1511 /* Stop processing this chunk. */
1515 /* Report an Invalid Mandatory Parameter. */
1516 static int sctp_process_inv_mandatory(const struct sctp_association *asoc,
1517 struct sctp_chunk *chunk,
1518 struct sctp_chunk **errp)
1520 /* Invalid Mandatory Parameter Error has no payload. */
1523 *errp = sctp_make_op_error_space(asoc, chunk, 0);
1526 sctp_init_cause(*errp, SCTP_ERROR_INV_PARAM, NULL, 0);
1528 /* Stop processing this chunk. */
1532 /* Do not attempt to handle the HOST_NAME parm. However, do
1533 * send back an indicator to the peer.
1535 static int sctp_process_hn_param(const struct sctp_association *asoc,
1536 union sctp_params param,
1537 struct sctp_chunk *chunk,
1538 struct sctp_chunk **errp)
1540 __u16 len = ntohs(param.p->length);
1542 /* Make an ERROR chunk. */
1544 *errp = sctp_make_op_error_space(asoc, chunk, len);
1547 sctp_init_cause(*errp, SCTP_ERROR_DNS_FAILED,
1550 /* Stop processing this chunk. */
1554 /* RFC 3.2.1 & the Implementers Guide 2.2.
1556 * The Parameter Types are encoded such that the
1557 * highest-order two bits specify the action that must be
1558 * taken if the processing endpoint does not recognize the
1561 * 00 - Stop processing this SCTP chunk and discard it,
1562 * do not process any further chunks within it.
1564 * 01 - Stop processing this SCTP chunk and discard it,
1565 * do not process any further chunks within it, and report
1566 * the unrecognized parameter in an 'Unrecognized
1567 * Parameter Type' (in either an ERROR or in the INIT ACK).
1569 * 10 - Skip this parameter and continue processing.
1571 * 11 - Skip this parameter and continue processing but
1572 * report the unrecognized parameter in an
1573 * 'Unrecognized Parameter Type' (in either an ERROR or in
1577 * 0 - discard the chunk
1578 * 1 - continue with the chunk
1580 static int sctp_process_unk_param(const struct sctp_association *asoc,
1581 union sctp_params param,
1582 struct sctp_chunk *chunk,
1583 struct sctp_chunk **errp)
1587 switch (param.p->type & SCTP_PARAM_ACTION_MASK) {
1588 case SCTP_PARAM_ACTION_DISCARD:
1591 case SCTP_PARAM_ACTION_DISCARD_ERR:
1593 /* Make an ERROR chunk, preparing enough room for
1594 * returning multiple unknown parameters.
1597 *errp = sctp_make_op_error_space(asoc, chunk,
1598 ntohs(chunk->chunk_hdr->length));
1601 sctp_init_cause(*errp, SCTP_ERROR_UNKNOWN_PARAM,
1603 WORD_ROUND(ntohs(param.p->length)));
1606 case SCTP_PARAM_ACTION_SKIP:
1608 case SCTP_PARAM_ACTION_SKIP_ERR:
1609 /* Make an ERROR chunk, preparing enough room for
1610 * returning multiple unknown parameters.
1613 *errp = sctp_make_op_error_space(asoc, chunk,
1614 ntohs(chunk->chunk_hdr->length));
1617 sctp_init_cause(*errp, SCTP_ERROR_UNKNOWN_PARAM,
1619 WORD_ROUND(ntohs(param.p->length)));
1621 /* If there is no memory for generating the ERROR
1622 * report as specified, an ABORT will be triggered
1623 * to the peer and the association won't be
1637 /* Find unrecognized parameters in the chunk.
1639 * 0 - discard the chunk
1640 * 1 - continue with the chunk
1642 static int sctp_verify_param(const struct sctp_association *asoc,
1643 union sctp_params param,
1645 struct sctp_chunk *chunk,
1646 struct sctp_chunk **err_chunk)
1650 /* FIXME - This routine is not looking at each parameter per the
1651 * chunk type, i.e., unrecognized parameters should be further
1652 * identified based on the chunk id.
1655 switch (param.p->type) {
1656 case SCTP_PARAM_IPV4_ADDRESS:
1657 case SCTP_PARAM_IPV6_ADDRESS:
1658 case SCTP_PARAM_COOKIE_PRESERVATIVE:
1659 case SCTP_PARAM_SUPPORTED_ADDRESS_TYPES:
1660 case SCTP_PARAM_STATE_COOKIE:
1661 case SCTP_PARAM_HEARTBEAT_INFO:
1662 case SCTP_PARAM_UNRECOGNIZED_PARAMETERS:
1663 case SCTP_PARAM_ECN_CAPABLE:
1666 case SCTP_PARAM_HOST_NAME_ADDRESS:
1667 /* Tell the peer, we won't support this param. */
1668 return sctp_process_hn_param(asoc, param, chunk, err_chunk);
1669 case SCTP_PARAM_FWD_TSN_SUPPORT:
1670 if (sctp_prsctp_enable)
1674 SCTP_DEBUG_PRINTK("Unrecognized param: %d for chunk %d.\n",
1675 ntohs(param.p->type), cid);
1676 return sctp_process_unk_param(asoc, param, chunk, err_chunk);
1683 /* Verify the INIT packet before we process it. */
1684 int sctp_verify_init(const struct sctp_association *asoc,
1686 sctp_init_chunk_t *peer_init,
1687 struct sctp_chunk *chunk,
1688 struct sctp_chunk **errp)
1690 union sctp_params param;
1693 /* Verify stream values are non-zero. */
1694 if ((0 == peer_init->init_hdr.num_outbound_streams) ||
1695 (0 == peer_init->init_hdr.num_inbound_streams)) {
1697 sctp_process_inv_mandatory(asoc, chunk, errp);
1701 /* Check for missing mandatory parameters. */
1702 sctp_walk_params(param, peer_init, init_hdr.params) {
1704 if (SCTP_PARAM_STATE_COOKIE == param.p->type)
1707 } /* for (loop through all parameters) */
1709 /* The only missing mandatory param possible today is
1710 * the state cookie for an INIT-ACK chunk.
1712 if ((SCTP_CID_INIT_ACK == cid) && !has_cookie) {
1713 sctp_process_missing_param(asoc, SCTP_PARAM_STATE_COOKIE,
1718 /* Find unrecognized parameters. */
1720 sctp_walk_params(param, peer_init, init_hdr.params) {
1722 if (!sctp_verify_param(asoc, param, cid, chunk, errp)) {
1723 if (SCTP_PARAM_HOST_NAME_ADDRESS == param.p->type)
1729 } /* for (loop through all parameters) */
1734 /* Unpack the parameters in an INIT packet into an association.
1735 * Returns 0 on failure, else success.
1736 * FIXME: This is an association method.
1738 int sctp_process_init(struct sctp_association *asoc, sctp_cid_t cid,
1739 const union sctp_addr *peer_addr,
1740 sctp_init_chunk_t *peer_init, int gfp)
1742 union sctp_params param;
1743 struct sctp_transport *transport;
1744 struct list_head *pos, *temp;
1747 /* We must include the address that the INIT packet came from.
1748 * This is the only address that matters for an INIT packet.
1749 * When processing a COOKIE ECHO, we retrieve the from address
1750 * of the INIT from the cookie.
1753 /* This implementation defaults to making the first transport
1754 * added as the primary transport. The source address seems to
1755 * be a a better choice than any of the embedded addresses.
1758 if(!sctp_assoc_add_peer(asoc, peer_addr, gfp))
1761 /* Process the initialization parameters. */
1763 sctp_walk_params(param, peer_init, init_hdr.params) {
1765 if (!sctp_process_param(asoc, param, peer_addr, gfp))
1769 /* The fixed INIT headers are always in network byte
1772 asoc->peer.i.init_tag =
1773 ntohl(peer_init->init_hdr.init_tag);
1774 asoc->peer.i.a_rwnd =
1775 ntohl(peer_init->init_hdr.a_rwnd);
1776 asoc->peer.i.num_outbound_streams =
1777 ntohs(peer_init->init_hdr.num_outbound_streams);
1778 asoc->peer.i.num_inbound_streams =
1779 ntohs(peer_init->init_hdr.num_inbound_streams);
1780 asoc->peer.i.initial_tsn =
1781 ntohl(peer_init->init_hdr.initial_tsn);
1783 /* Apply the upper bounds for output streams based on peer's
1784 * number of inbound streams.
1786 if (asoc->c.sinit_num_ostreams >
1787 ntohs(peer_init->init_hdr.num_inbound_streams)) {
1788 asoc->c.sinit_num_ostreams =
1789 ntohs(peer_init->init_hdr.num_inbound_streams);
1792 if (asoc->c.sinit_max_instreams >
1793 ntohs(peer_init->init_hdr.num_outbound_streams)) {
1794 asoc->c.sinit_max_instreams =
1795 ntohs(peer_init->init_hdr.num_outbound_streams);
1798 /* Copy Initiation tag from INIT to VT_peer in cookie. */
1799 asoc->c.peer_vtag = asoc->peer.i.init_tag;
1801 /* Peer Rwnd : Current calculated value of the peer's rwnd. */
1802 asoc->peer.rwnd = asoc->peer.i.a_rwnd;
1804 /* Copy cookie in case we need to resend COOKIE-ECHO. */
1805 cookie = asoc->peer.cookie;
1807 asoc->peer.cookie = kmalloc(asoc->peer.cookie_len, gfp);
1808 if (!asoc->peer.cookie)
1810 memcpy(asoc->peer.cookie, cookie, asoc->peer.cookie_len);
1813 /* RFC 2960 7.2.1 The initial value of ssthresh MAY be arbitrarily
1814 * high (for example, implementations MAY use the size of the receiver
1815 * advertised window).
1817 list_for_each(pos, &asoc->peer.transport_addr_list) {
1818 transport = list_entry(pos, struct sctp_transport, transports);
1819 transport->ssthresh = asoc->peer.i.a_rwnd;
1822 /* Set up the TSN tracking pieces. */
1823 sctp_tsnmap_init(&asoc->peer.tsn_map, SCTP_TSN_MAP_SIZE,
1824 asoc->peer.i.initial_tsn);
1826 /* RFC 2960 6.5 Stream Identifier and Stream Sequence Number
1828 * The stream sequence number in all the streams shall start
1829 * from 0 when the association is established. Also, when the
1830 * stream sequence number reaches the value 65535 the next
1831 * stream sequence number shall be set to 0.
1834 /* Allocate storage for the negotiated streams if it is not a temporary * association.
1837 sctp_assoc_t assoc_id;
1839 asoc->ssnmap = sctp_ssnmap_new(asoc->c.sinit_max_instreams,
1840 asoc->c.sinit_num_ostreams, gfp);
1845 if (unlikely(!idr_pre_get(&sctp_assocs_id, gfp)))
1847 spin_lock_bh(&sctp_assocs_id_lock);
1848 assoc_id = (sctp_assoc_t)idr_get_new(&sctp_assocs_id,
1850 spin_unlock_bh(&sctp_assocs_id_lock);
1851 } while (unlikely((int)assoc_id == -1));
1853 asoc->assoc_id = assoc_id;
1856 /* ADDIP Section 4.1 ASCONF Chunk Procedures
1858 * When an endpoint has an ASCONF signaled change to be sent to the
1859 * remote endpoint it should do the following:
1861 * A2) A serial number should be assigned to the Chunk. The serial
1862 * number should be a monotonically increasing number. All serial
1863 * numbers are defined to be initialized at the start of the
1864 * association to the same value as the Initial TSN.
1866 asoc->peer.addip_serial = asoc->peer.i.initial_tsn - 1;
1870 /* Release the transport structures. */
1871 list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
1872 transport = list_entry(pos, struct sctp_transport, transports);
1874 sctp_transport_free(transport);
1881 /* Update asoc with the option described in param.
1883 * RFC2960 3.3.2.1 Optional/Variable Length Parameters in INIT
1885 * asoc is the association to update.
1886 * param is the variable length parameter to use for update.
1887 * cid tells us if this is an INIT, INIT ACK or COOKIE ECHO.
1888 * If the current packet is an INIT we want to minimize the amount of
1889 * work we do. In particular, we should not build transport
1890 * structures for the addresses.
1892 int sctp_process_param(struct sctp_association *asoc, union sctp_params param,
1893 const union sctp_addr *peer_addr, int gfp)
1895 union sctp_addr addr;
1903 /* We maintain all INIT parameters in network byte order all the
1904 * time. This allows us to not worry about whether the parameters
1905 * came from a fresh INIT, and INIT ACK, or were stored in a cookie.
1907 switch (param.p->type) {
1908 case SCTP_PARAM_IPV6_ADDRESS:
1909 if (PF_INET6 != asoc->base.sk->sk_family)
1912 case SCTP_PARAM_IPV4_ADDRESS:
1913 af = sctp_get_af_specific(param_type2af(param.p->type));
1914 af->from_addr_param(&addr, param.addr, asoc->peer.port, 0);
1915 scope = sctp_scope(peer_addr);
1916 if (sctp_in_scope(&addr, scope))
1917 if (!sctp_assoc_add_peer(asoc, &addr, gfp))
1921 case SCTP_PARAM_COOKIE_PRESERVATIVE:
1922 if (!sctp_cookie_preserve_enable)
1925 stale = ntohl(param.life->lifespan_increment);
1927 /* Suggested Cookie Life span increment's unit is msec,
1930 asoc->cookie_life.tv_sec += stale / 1000;
1931 asoc->cookie_life.tv_usec += (stale % 1000) * 1000;
1934 case SCTP_PARAM_HOST_NAME_ADDRESS:
1935 SCTP_DEBUG_PRINTK("unimplemented SCTP_HOST_NAME_ADDRESS\n");
1938 case SCTP_PARAM_SUPPORTED_ADDRESS_TYPES:
1939 /* Turn off the default values first so we'll know which
1940 * ones are really set by the peer.
1942 asoc->peer.ipv4_address = 0;
1943 asoc->peer.ipv6_address = 0;
1945 /* Cycle through address types; avoid divide by 0. */
1946 sat = ntohs(param.p->length) - sizeof(sctp_paramhdr_t);
1948 sat /= sizeof(__u16);
1950 for (i = 0; i < sat; ++i) {
1951 switch (param.sat->types[i]) {
1952 case SCTP_PARAM_IPV4_ADDRESS:
1953 asoc->peer.ipv4_address = 1;
1956 case SCTP_PARAM_IPV6_ADDRESS:
1957 asoc->peer.ipv6_address = 1;
1960 case SCTP_PARAM_HOST_NAME_ADDRESS:
1961 asoc->peer.hostname_address = 1;
1964 default: /* Just ignore anything else. */
1970 case SCTP_PARAM_STATE_COOKIE:
1971 asoc->peer.cookie_len =
1972 ntohs(param.p->length) - sizeof(sctp_paramhdr_t);
1973 asoc->peer.cookie = param.cookie->body;
1976 case SCTP_PARAM_HEARTBEAT_INFO:
1977 /* Would be odd to receive, but it causes no problems. */
1980 case SCTP_PARAM_UNRECOGNIZED_PARAMETERS:
1981 /* Rejected during verify stage. */
1984 case SCTP_PARAM_ECN_CAPABLE:
1985 asoc->peer.ecn_capable = 1;
1988 case SCTP_PARAM_FWD_TSN_SUPPORT:
1989 if (sctp_prsctp_enable) {
1990 asoc->peer.prsctp_capable = 1;
1995 /* Any unrecognized parameters should have been caught
1996 * and handled by sctp_verify_param() which should be
1997 * called prior to this routine. Simply log the error
2000 SCTP_DEBUG_PRINTK("Ignoring param: %d for association %p.\n",
2001 ntohs(param.p->type), asoc);
2008 /* Select a new verification tag. */
2009 __u32 sctp_generate_tag(const struct sctp_endpoint *ep)
2011 /* I believe that this random number generator complies with RFC1750.
2012 * A tag of 0 is reserved for special cases (e.g. INIT).
2017 get_random_bytes(&x, sizeof(__u32));
2023 /* Select an initial TSN to send during startup. */
2024 __u32 sctp_generate_tsn(const struct sctp_endpoint *ep)
2028 get_random_bytes(&retval, sizeof(__u32));
2033 * ADDIP 3.1.1 Address Configuration Change Chunk (ASCONF)
2035 * 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
2036 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2037 * | Type = 0xC1 | Chunk Flags | Chunk Length |
2038 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2040 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2041 * | Address Parameter |
2042 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2043 * | ASCONF Parameter #1 |
2044 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2048 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2049 * | ASCONF Parameter #N |
2050 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2052 * Address Parameter and other parameter will not be wrapped in this function
2054 struct sctp_chunk *sctp_make_asconf(struct sctp_association *asoc,
2055 union sctp_addr *addr, int vparam_len)
2057 sctp_addiphdr_t asconf;
2058 struct sctp_chunk *retval;
2059 int length = sizeof(asconf) + vparam_len;
2060 union sctp_addr_param addrparam;
2062 struct sctp_af *af = sctp_get_af_specific(addr->v4.sin_family);
2064 addrlen = af->to_addr_param(addr, &addrparam);
2069 /* Create the chunk. */
2070 retval = sctp_make_chunk(asoc, SCTP_CID_ASCONF, 0, length);
2074 asconf.serial = htonl(asoc->addip_serial++);
2076 retval->subh.addip_hdr =
2077 sctp_addto_chunk(retval, sizeof(asconf), &asconf);
2078 retval->param_hdr.v =
2079 sctp_addto_chunk(retval, addrlen, &addrparam);
2085 * 3.2.1 Add IP Address
2087 * 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
2088 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2089 * | Type = 0xC001 | Length = Variable |
2090 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2091 * | ASCONF-Request Correlation ID |
2092 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2093 * | Address Parameter |
2094 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2096 * 3.2.2 Delete IP Address
2098 * 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
2099 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2100 * | Type = 0xC002 | Length = Variable |
2101 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2102 * | ASCONF-Request Correlation ID |
2103 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2104 * | Address Parameter |
2105 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2108 struct sctp_chunk *sctp_make_asconf_update_ip(struct sctp_association *asoc,
2109 union sctp_addr *laddr,
2110 struct sockaddr *addrs,
2114 sctp_addip_param_t param;
2115 struct sctp_chunk *retval;
2116 union sctp_addr_param addr_param;
2117 union sctp_addr *addr;
2120 int paramlen = sizeof(param);
2121 int addr_param_len = 0;
2125 /* Get total length of all the address parameters. */
2127 for (i = 0; i < addrcnt; i++) {
2128 addr = (union sctp_addr *)addr_buf;
2129 af = sctp_get_af_specific(addr->v4.sin_family);
2130 addr_param_len = af->to_addr_param(addr, &addr_param);
2132 totallen += paramlen;
2133 totallen += addr_param_len;
2135 addr_buf += af->sockaddr_len;
2138 /* Create an asconf chunk with the required length. */
2139 retval = sctp_make_asconf(asoc, laddr, totallen);
2143 /* Add the address parameters to the asconf chunk. */
2145 for (i = 0; i < addrcnt; i++) {
2146 addr = (union sctp_addr *)addr_buf;
2147 af = sctp_get_af_specific(addr->v4.sin_family);
2148 addr_param_len = af->to_addr_param(addr, &addr_param);
2149 param.param_hdr.type = flags;
2150 param.param_hdr.length = htons(paramlen + addr_param_len);
2153 sctp_addto_chunk(retval, paramlen, ¶m);
2154 sctp_addto_chunk(retval, addr_param_len, &addr_param);
2156 addr_buf += af->sockaddr_len;
2162 * 3.2.4 Set Primary IP Address
2164 * 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
2165 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2166 * | Type =0xC004 | Length = Variable |
2167 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2168 * | ASCONF-Request Correlation ID |
2169 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2170 * | Address Parameter |
2171 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2173 * Create an ASCONF chunk with Set Primary IP address parameter.
2175 struct sctp_chunk *sctp_make_asconf_set_prim(struct sctp_association *asoc,
2176 union sctp_addr *addr)
2178 sctp_addip_param_t param;
2179 struct sctp_chunk *retval;
2180 int len = sizeof(param);
2181 union sctp_addr_param addrparam;
2183 struct sctp_af *af = sctp_get_af_specific(addr->v4.sin_family);
2185 addrlen = af->to_addr_param(addr, &addrparam);
2190 /* Create the chunk and make asconf header. */
2191 retval = sctp_make_asconf(asoc, addr, len);
2195 param.param_hdr.type = SCTP_PARAM_SET_PRIMARY;
2196 param.param_hdr.length = htons(len);
2199 sctp_addto_chunk(retval, sizeof(param), ¶m);
2200 sctp_addto_chunk(retval, addrlen, &addrparam);
2205 /* ADDIP 3.1.2 Address Configuration Acknowledgement Chunk (ASCONF-ACK)
2207 * 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
2208 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2209 * | Type = 0x80 | Chunk Flags | Chunk Length |
2210 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2212 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2213 * | ASCONF Parameter Response#1 |
2214 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2218 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2219 * | ASCONF Parameter Response#N |
2220 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2222 * Create an ASCONF_ACK chunk with enough space for the parameter responses.
2224 struct sctp_chunk *sctp_make_asconf_ack(const struct sctp_association *asoc,
2225 __u32 serial, int vparam_len)
2227 sctp_addiphdr_t asconf;
2228 struct sctp_chunk *retval;
2229 int length = sizeof(asconf) + vparam_len;
2231 /* Create the chunk. */
2232 retval = sctp_make_chunk(asoc, SCTP_CID_ASCONF_ACK, 0, length);
2236 asconf.serial = htonl(serial);
2238 retval->subh.addip_hdr =
2239 sctp_addto_chunk(retval, sizeof(asconf), &asconf);
2244 /* Add response parameters to an ASCONF_ACK chunk. */
2245 static void sctp_add_asconf_response(struct sctp_chunk *chunk, __u32 crr_id,
2246 __u16 err_code, sctp_addip_param_t *asconf_param)
2248 sctp_addip_param_t ack_param;
2249 sctp_errhdr_t err_param;
2250 int asconf_param_len = 0;
2251 int err_param_len = 0;
2252 __u16 response_type;
2254 if (SCTP_ERROR_NO_ERROR == err_code) {
2255 response_type = SCTP_PARAM_SUCCESS_REPORT;
2257 response_type = SCTP_PARAM_ERR_CAUSE;
2258 err_param_len = sizeof(err_param);
2261 ntohs(asconf_param->param_hdr.length);
2264 /* Add Success Indication or Error Cause Indication parameter. */
2265 ack_param.param_hdr.type = response_type;
2266 ack_param.param_hdr.length = htons(sizeof(ack_param) +
2269 ack_param.crr_id = crr_id;
2270 sctp_addto_chunk(chunk, sizeof(ack_param), &ack_param);
2272 if (SCTP_ERROR_NO_ERROR == err_code)
2275 /* Add Error Cause parameter. */
2276 err_param.cause = err_code;
2277 err_param.length = htons(err_param_len + asconf_param_len);
2278 sctp_addto_chunk(chunk, err_param_len, &err_param);
2280 /* Add the failed TLV copied from ASCONF chunk. */
2282 sctp_addto_chunk(chunk, asconf_param_len, asconf_param);
2285 /* Process a asconf parameter. */
2286 static __u16 sctp_process_asconf_param(struct sctp_association *asoc,
2287 struct sctp_chunk *asconf,
2288 sctp_addip_param_t *asconf_param)
2290 struct sctp_transport *peer;
2292 union sctp_addr addr;
2293 struct list_head *pos;
2294 union sctp_addr_param *addr_param;
2296 addr_param = (union sctp_addr_param *)
2297 ((void *)asconf_param + sizeof(sctp_addip_param_t));
2299 af = sctp_get_af_specific(param_type2af(addr_param->v4.param_hdr.type));
2301 return SCTP_ERROR_INV_PARAM;
2303 af->from_addr_param(&addr, addr_param, asoc->peer.port, 0);
2304 switch (asconf_param->param_hdr.type) {
2305 case SCTP_PARAM_ADD_IP:
2306 /* ADDIP 4.3 D9) If an endpoint receives an ADD IP address
2307 * request and does not have the local resources to add this
2308 * new address to the association, it MUST return an Error
2309 * Cause TLV set to the new error code 'Operation Refused
2310 * Due to Resource Shortage'.
2313 peer = sctp_assoc_add_peer(asoc, &addr, GFP_ATOMIC);
2315 return SCTP_ERROR_RSRC_LOW;
2317 /* Start the heartbeat timer. */
2318 if (!mod_timer(&peer->hb_timer, sctp_transport_timeout(peer)))
2319 sctp_transport_hold(peer);
2321 case SCTP_PARAM_DEL_IP:
2322 /* ADDIP 4.3 D7) If a request is received to delete the
2323 * last remaining IP address of a peer endpoint, the receiver
2324 * MUST send an Error Cause TLV with the error cause set to the
2325 * new error code 'Request to Delete Last Remaining IP Address'.
2327 pos = asoc->peer.transport_addr_list.next;
2328 if (pos->next == &asoc->peer.transport_addr_list)
2329 return SCTP_ERROR_DEL_LAST_IP;
2331 /* ADDIP 4.3 D8) If a request is received to delete an IP
2332 * address which is also the source address of the IP packet
2333 * which contained the ASCONF chunk, the receiver MUST reject
2334 * this request. To reject the request the receiver MUST send
2335 * an Error Cause TLV set to the new error code 'Request to
2336 * Delete Source IP Address'
2338 if (sctp_cmp_addr_exact(sctp_source(asconf), &addr))
2339 return SCTP_ERROR_DEL_SRC_IP;
2341 sctp_assoc_del_peer(asoc, &addr);
2343 case SCTP_PARAM_SET_PRIMARY:
2344 peer = sctp_assoc_lookup_paddr(asoc, &addr);
2346 return SCTP_ERROR_INV_PARAM;
2348 sctp_assoc_set_primary(asoc, peer);
2351 return SCTP_ERROR_INV_PARAM;
2355 return SCTP_ERROR_NO_ERROR;
2358 /* Process an incoming ASCONF chunk with the next expected serial no. and
2359 * return an ASCONF_ACK chunk to be sent in response.
2361 struct sctp_chunk *sctp_process_asconf(struct sctp_association *asoc,
2362 struct sctp_chunk *asconf)
2364 sctp_addiphdr_t *hdr;
2365 union sctp_addr_param *addr_param;
2366 sctp_addip_param_t *asconf_param;
2367 struct sctp_chunk *asconf_ack;
2371 int chunk_len = asconf->skb->len;
2373 int all_param_pass = 1;
2375 hdr = (sctp_addiphdr_t *)asconf->skb->data;
2376 serial = ntohl(hdr->serial);
2378 /* Skip the addiphdr and store a pointer to address parameter. */
2379 length = sizeof(sctp_addiphdr_t);
2380 addr_param = (union sctp_addr_param *)(asconf->skb->data + length);
2381 chunk_len -= length;
2383 /* Skip the address parameter and store a pointer to the first
2386 length = ntohs(addr_param->v4.param_hdr.length);
2387 asconf_param = (sctp_addip_param_t *)((void *)addr_param + length);
2388 chunk_len -= length;
2390 /* create an ASCONF_ACK chunk.
2391 * Based on the definitions of parameters, we know that the size of
2392 * ASCONF_ACK parameters are less than or equal to the twice of ASCONF
2395 asconf_ack = sctp_make_asconf_ack(asoc, serial, chunk_len * 2);
2399 /* Process the TLVs contained within the ASCONF chunk. */
2400 while (chunk_len > 0) {
2401 err_code = sctp_process_asconf_param(asoc, asconf,
2404 * If an error response is received for a TLV parameter,
2405 * all TLVs with no response before the failed TLV are
2406 * considered successful if not reported. All TLVs after
2407 * the failed response are considered unsuccessful unless
2408 * a specific success indication is present for the parameter.
2410 if (SCTP_ERROR_NO_ERROR != err_code)
2413 if (!all_param_pass)
2414 sctp_add_asconf_response(asconf_ack,
2415 asconf_param->crr_id, err_code,
2418 /* ADDIP 4.3 D11) When an endpoint receiving an ASCONF to add
2419 * an IP address sends an 'Out of Resource' in its response, it
2420 * MUST also fail any subsequent add or delete requests bundled
2423 if (SCTP_ERROR_RSRC_LOW == err_code)
2426 /* Move to the next ASCONF param. */
2427 length = ntohs(asconf_param->param_hdr.length);
2428 asconf_param = (sctp_addip_param_t *)((void *)asconf_param +
2430 chunk_len -= length;
2434 asoc->peer.addip_serial++;
2436 /* If we are sending a new ASCONF_ACK hold a reference to it in assoc
2437 * after freeing the reference to old asconf ack if any.
2440 if (asoc->addip_last_asconf_ack)
2441 sctp_chunk_free(asoc->addip_last_asconf_ack);
2443 sctp_chunk_hold(asconf_ack);
2444 asoc->addip_last_asconf_ack = asconf_ack;
2450 /* Process a asconf parameter that is successfully acked. */
2451 static int sctp_asconf_param_success(struct sctp_association *asoc,
2452 sctp_addip_param_t *asconf_param)
2455 union sctp_addr addr;
2456 struct sctp_bind_addr *bp = &asoc->base.bind_addr;
2457 union sctp_addr_param *addr_param;
2460 addr_param = (union sctp_addr_param *)
2461 ((void *)asconf_param + sizeof(sctp_addip_param_t));
2463 /* We have checked the packet before, so we do not check again. */
2464 af = sctp_get_af_specific(param_type2af(addr_param->v4.param_hdr.type));
2465 af->from_addr_param(&addr, addr_param, bp->port, 0);
2467 switch (asconf_param->param_hdr.type) {
2468 case SCTP_PARAM_ADD_IP:
2469 sctp_local_bh_disable();
2470 sctp_write_lock(&asoc->base.addr_lock);
2471 retval = sctp_add_bind_addr(bp, &addr, GFP_ATOMIC);
2472 sctp_write_unlock(&asoc->base.addr_lock);
2473 sctp_local_bh_enable();
2475 case SCTP_PARAM_DEL_IP:
2476 sctp_local_bh_disable();
2477 sctp_write_lock(&asoc->base.addr_lock);
2478 retval = sctp_del_bind_addr(bp, &addr);
2479 sctp_write_unlock(&asoc->base.addr_lock);
2480 sctp_local_bh_enable();
2489 /* Get the corresponding ASCONF response error code from the ASCONF_ACK chunk
2490 * for the given asconf parameter. If there is no response for this parameter,
2491 * return the error code based on the third argument 'no_err'.
2493 * A7) If an error response is received for a TLV parameter, all TLVs with no
2494 * response before the failed TLV are considered successful if not reported.
2495 * All TLVs after the failed response are considered unsuccessful unless a
2496 * specific success indication is present for the parameter.
2498 static __u16 sctp_get_asconf_response(struct sctp_chunk *asconf_ack,
2499 sctp_addip_param_t *asconf_param,
2502 sctp_addip_param_t *asconf_ack_param;
2503 sctp_errhdr_t *err_param;
2505 int asconf_ack_len = asconf_ack->skb->len;
2509 err_code = SCTP_ERROR_NO_ERROR;
2511 err_code = SCTP_ERROR_REQ_REFUSED;
2513 /* Skip the addiphdr from the asconf_ack chunk and store a pointer to
2514 * the first asconf_ack parameter.
2516 length = sizeof(sctp_addiphdr_t);
2517 asconf_ack_param = (sctp_addip_param_t *)(asconf_ack->skb->data +
2519 asconf_ack_len -= length;
2521 while (asconf_ack_len > 0) {
2522 if (asconf_ack_param->crr_id == asconf_param->crr_id) {
2523 switch(asconf_ack_param->param_hdr.type) {
2524 case SCTP_PARAM_SUCCESS_REPORT:
2525 return SCTP_ERROR_NO_ERROR;
2526 case SCTP_PARAM_ERR_CAUSE:
2527 length = sizeof(sctp_addip_param_t);
2528 err_param = (sctp_errhdr_t *)
2529 ((void *)asconf_ack_param + length);
2530 asconf_ack_len -= length;
2531 if (asconf_ack_len > 0)
2532 return err_param->cause;
2534 return SCTP_ERROR_INV_PARAM;
2537 return SCTP_ERROR_INV_PARAM;
2541 length = ntohs(asconf_ack_param->param_hdr.length);
2542 asconf_ack_param = (sctp_addip_param_t *)
2543 ((void *)asconf_ack_param + length);
2544 asconf_ack_len -= length;
2550 /* Process an incoming ASCONF_ACK chunk against the cached last ASCONF chunk. */
2551 int sctp_process_asconf_ack(struct sctp_association *asoc,
2552 struct sctp_chunk *asconf_ack)
2554 struct sctp_chunk *asconf = asoc->addip_last_asconf;
2555 union sctp_addr_param *addr_param;
2556 sctp_addip_param_t *asconf_param;
2558 int asconf_len = asconf->skb->len;
2559 int all_param_pass = 0;
2562 __u16 err_code = SCTP_ERROR_NO_ERROR;
2564 /* Skip the chunkhdr and addiphdr from the last asconf sent and store
2565 * a pointer to address parameter.
2567 length = sizeof(sctp_addip_chunk_t);
2568 addr_param = (union sctp_addr_param *)(asconf->skb->data + length);
2569 asconf_len -= length;
2571 /* Skip the address parameter in the last asconf sent and store a
2572 * pointer to the first asconf paramter.
2574 length = ntohs(addr_param->v4.param_hdr.length);
2575 asconf_param = (sctp_addip_param_t *)((void *)addr_param + length);
2576 asconf_len -= length;
2579 * A8) If there is no response(s) to specific TLV parameter(s), and no
2580 * failures are indicated, then all request(s) are considered
2583 if (asconf_ack->skb->len == sizeof(sctp_addiphdr_t))
2586 /* Process the TLVs contained in the last sent ASCONF chunk. */
2587 while (asconf_len > 0) {
2589 err_code = SCTP_ERROR_NO_ERROR;
2591 err_code = sctp_get_asconf_response(asconf_ack,
2594 if (no_err && (SCTP_ERROR_NO_ERROR != err_code))
2599 case SCTP_ERROR_NO_ERROR:
2600 retval = sctp_asconf_param_success(asoc, asconf_param);
2603 case SCTP_ERROR_RSRC_LOW:
2607 case SCTP_ERROR_INV_PARAM:
2608 /* Disable sending this type of asconf parameter in
2611 asoc->peer.addip_disabled_mask |=
2612 asconf_param->param_hdr.type;
2615 case SCTP_ERROR_REQ_REFUSED:
2616 case SCTP_ERROR_DEL_LAST_IP:
2617 case SCTP_ERROR_DEL_SRC_IP:
2622 /* Skip the processed asconf parameter and move to the next
2625 length = ntohs(asconf_param->param_hdr.length);
2626 asconf_param = (sctp_addip_param_t *)((void *)asconf_param +
2628 asconf_len -= length;
2631 /* Free the cached last sent asconf chunk. */
2632 sctp_chunk_free(asconf);
2633 asoc->addip_last_asconf = NULL;
2635 /* Send the next asconf chunk from the addip chunk queue. */
2636 asconf = (struct sctp_chunk *)__skb_dequeue(&asoc->addip_chunks);
2638 /* Hold the chunk until an ASCONF_ACK is received. */
2639 sctp_chunk_hold(asconf);
2640 if (sctp_primitive_ASCONF(asoc, asconf))
2641 sctp_chunk_free(asconf);
2643 asoc->addip_last_asconf = asconf;
2649 /* Make a FWD TSN chunk. */
2650 struct sctp_chunk *sctp_make_fwdtsn(const struct sctp_association *asoc,
2651 __u32 new_cum_tsn, size_t nstreams,
2652 struct sctp_fwdtsn_skip *skiplist)
2654 struct sctp_chunk *retval = NULL;
2655 struct sctp_fwdtsn_chunk *ftsn_chunk;
2656 struct sctp_fwdtsn_hdr ftsn_hdr;
2657 struct sctp_fwdtsn_skip skip;
2661 hint = (nstreams + 1) * sizeof(__u32);
2663 /* Maybe set the T-bit if we have no association. */
2664 retval = sctp_make_chunk(asoc, SCTP_CID_FWD_TSN, 0, hint);
2669 ftsn_chunk = (struct sctp_fwdtsn_chunk *)retval->subh.fwdtsn_hdr;
2671 ftsn_hdr.new_cum_tsn = htonl(new_cum_tsn);
2672 retval->subh.fwdtsn_hdr =
2673 sctp_addto_chunk(retval, sizeof(ftsn_hdr), &ftsn_hdr);
2675 for (i = 0; i < nstreams; i++) {
2676 skip.stream = skiplist[i].stream;
2677 skip.ssn = skiplist[i].ssn;
2678 sctp_addto_chunk(retval, sizeof(skip), &skip);