1 /* SCTP kernel reference Implementation
2 * (C) Copyright IBM Corp. 2001, 2003
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;
71 struct sctp_chunk *sctp_make_chunk(const struct sctp_association *asoc,
72 __u8 type, __u8 flags, int paylen);
73 static sctp_cookie_param_t *sctp_pack_cookie(const struct sctp_endpoint *ep,
74 const struct sctp_association *asoc,
75 const struct sctp_chunk *init_chunk,
77 const __u8 *raw_addrs, int addrs_len);
78 static int sctp_process_param(struct sctp_association *asoc,
79 union sctp_params param,
80 const union sctp_addr *peer_addr,
83 /* What was the inbound interface for this chunk? */
84 int sctp_chunk_iif(const struct sctp_chunk *chunk)
89 af = sctp_get_af_specific(ipver2af(chunk->skb->nh.iph->version));
91 iif = af->skb_iif(chunk->skb);
96 /* RFC 2960 3.3.2 Initiation (INIT) (1)
98 * Note 2: The ECN capable field is reserved for future use of
99 * Explicit Congestion Notification.
101 static const struct sctp_paramhdr ecap_param = {
102 SCTP_PARAM_ECN_CAPABLE,
103 __constant_htons(sizeof(struct sctp_paramhdr)),
105 static const struct sctp_paramhdr prsctp_param = {
106 SCTP_PARAM_FWD_TSN_SUPPORT,
107 __constant_htons(sizeof(struct sctp_paramhdr)),
110 /* A helper to initialize to initialize an op error inside a
111 * provided chunk, as most cause codes will be embedded inside an
114 void sctp_init_cause(struct sctp_chunk *chunk, __u16 cause_code,
115 const void *payload, size_t paylen)
121 /* Cause code constants are now defined in network order. */
122 err.cause = cause_code;
123 len = sizeof(sctp_errhdr_t) + paylen;
125 err.length = htons(len);
127 sctp_addto_chunk(chunk, sizeof(sctp_errhdr_t), &err);
128 chunk->subh.err_hdr = sctp_addto_chunk(chunk, paylen, payload);
131 /* 3.3.2 Initiation (INIT) (1)
133 * This chunk is used to initiate a SCTP association between two
134 * endpoints. The format of the INIT chunk is shown below:
137 * 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
138 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
139 * | Type = 1 | Chunk Flags | Chunk Length |
140 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
142 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
143 * | Advertised Receiver Window Credit (a_rwnd) |
144 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
145 * | Number of Outbound Streams | Number of Inbound Streams |
146 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
148 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
150 * / Optional/Variable-Length Parameters /
152 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
155 * The INIT chunk contains the following parameters. Unless otherwise
156 * noted, each parameter MUST only be included once in the INIT chunk.
158 * Fixed Parameters Status
159 * ----------------------------------------------
160 * Initiate Tag Mandatory
161 * Advertised Receiver Window Credit Mandatory
162 * Number of Outbound Streams Mandatory
163 * Number of Inbound Streams Mandatory
164 * Initial TSN Mandatory
166 * Variable Parameters Status Type Value
167 * -------------------------------------------------------------
168 * IPv4 Address (Note 1) Optional 5
169 * IPv6 Address (Note 1) Optional 6
170 * Cookie Preservative Optional 9
171 * Reserved for ECN Capable (Note 2) Optional 32768 (0x8000)
172 * Host Name Address (Note 3) Optional 11
173 * Supported Address Types (Note 4) Optional 12
175 struct sctp_chunk *sctp_make_init(const struct sctp_association *asoc,
176 const struct sctp_bind_addr *bp,
177 int gfp, int vparam_len)
180 union sctp_params addrs;
182 struct sctp_chunk *retval = NULL;
183 int num_types, addrs_len = 0;
185 sctp_supported_addrs_param_t sat;
187 sctp_adaption_ind_param_t aiparam;
189 /* RFC 2960 3.3.2 Initiation (INIT) (1)
191 * Note 1: The INIT chunks can contain multiple addresses that
192 * can be IPv4 and/or IPv6 in any combination.
196 /* Convert the provided bind address list to raw format. */
197 addrs = sctp_bind_addrs_to_raw(bp, &addrs_len, gfp);
199 init.init_tag = htonl(asoc->c.my_vtag);
200 init.a_rwnd = htonl(asoc->rwnd);
201 init.num_outbound_streams = htons(asoc->c.sinit_num_ostreams);
202 init.num_inbound_streams = htons(asoc->c.sinit_max_instreams);
203 init.initial_tsn = htonl(asoc->c.initial_tsn);
205 /* How many address types are needed? */
206 sp = sctp_sk(asoc->base.sk);
207 num_types = sp->pf->supported_addrs(sp, types);
209 chunksize = sizeof(init) + addrs_len + SCTP_SAT_LEN(num_types);
210 chunksize += sizeof(ecap_param);
211 if (sctp_prsctp_enable)
212 chunksize += sizeof(prsctp_param);
213 chunksize += sizeof(aiparam);
214 chunksize += vparam_len;
216 /* RFC 2960 3.3.2 Initiation (INIT) (1)
218 * Note 3: An INIT chunk MUST NOT contain more than one Host
219 * Name address parameter. Moreover, the sender of the INIT
220 * MUST NOT combine any other address types with the Host Name
221 * address in the INIT. The receiver of INIT MUST ignore any
222 * other address types if the Host Name address parameter is
223 * present in the received INIT chunk.
225 * PLEASE DO NOT FIXME [This version does not support Host Name.]
228 retval = sctp_make_chunk(asoc, SCTP_CID_INIT, 0, chunksize);
232 retval->subh.init_hdr =
233 sctp_addto_chunk(retval, sizeof(init), &init);
234 retval->param_hdr.v =
235 sctp_addto_chunk(retval, addrs_len, addrs.v);
237 /* RFC 2960 3.3.2 Initiation (INIT) (1)
239 * Note 4: This parameter, when present, specifies all the
240 * address types the sending endpoint can support. The absence
241 * of this parameter indicates that the sending endpoint can
242 * support any address type.
244 sat.param_hdr.type = SCTP_PARAM_SUPPORTED_ADDRESS_TYPES;
245 sat.param_hdr.length = htons(SCTP_SAT_LEN(num_types));
246 sctp_addto_chunk(retval, sizeof(sat), &sat);
247 sctp_addto_chunk(retval, num_types * sizeof(__u16), &types);
249 sctp_addto_chunk(retval, sizeof(ecap_param), &ecap_param);
250 if (sctp_prsctp_enable)
251 sctp_addto_chunk(retval, sizeof(prsctp_param), &prsctp_param);
252 aiparam.param_hdr.type = SCTP_PARAM_ADAPTION_LAYER_IND;
253 aiparam.param_hdr.length = htons(sizeof(aiparam));
254 aiparam.adaption_ind = htonl(sp->adaption_ind);
255 sctp_addto_chunk(retval, sizeof(aiparam), &aiparam);
262 struct sctp_chunk *sctp_make_init_ack(const struct sctp_association *asoc,
263 const struct sctp_chunk *chunk,
264 int gfp, int unkparam_len)
266 sctp_inithdr_t initack;
267 struct sctp_chunk *retval;
268 union sctp_params addrs;
270 sctp_cookie_param_t *cookie;
273 sctp_adaption_ind_param_t aiparam;
277 /* Note: there may be no addresses to embed. */
278 addrs = sctp_bind_addrs_to_raw(&asoc->base.bind_addr, &addrs_len, gfp);
280 initack.init_tag = htonl(asoc->c.my_vtag);
281 initack.a_rwnd = htonl(asoc->rwnd);
282 initack.num_outbound_streams = htons(asoc->c.sinit_num_ostreams);
283 initack.num_inbound_streams = htons(asoc->c.sinit_max_instreams);
284 initack.initial_tsn = htonl(asoc->c.initial_tsn);
286 /* FIXME: We really ought to build the cookie right
287 * into the packet instead of allocating more fresh memory.
289 cookie = sctp_pack_cookie(asoc->ep, asoc, chunk, &cookie_len,
294 /* Calculate the total size of allocation, include the reserved
295 * space for reporting unknown parameters if it is specified.
297 chunksize = sizeof(initack) + addrs_len + cookie_len + unkparam_len;
299 /* Tell peer that we'll do ECN only if peer advertised such cap. */
300 if (asoc->peer.ecn_capable)
301 chunksize += sizeof(ecap_param);
303 /* Tell peer that we'll do PR-SCTP only if peer advertised. */
304 if (asoc->peer.prsctp_capable)
305 chunksize += sizeof(prsctp_param);
307 chunksize += sizeof(aiparam);
309 /* Now allocate and fill out the chunk. */
310 retval = sctp_make_chunk(asoc, SCTP_CID_INIT_ACK, 0, chunksize);
314 /* Per the advice in RFC 2960 6.4, send this reply to
315 * the source of the INIT packet.
317 retval->transport = chunk->transport;
318 retval->subh.init_hdr =
319 sctp_addto_chunk(retval, sizeof(initack), &initack);
320 retval->param_hdr.v = sctp_addto_chunk(retval, addrs_len, addrs.v);
321 sctp_addto_chunk(retval, cookie_len, cookie);
322 if (asoc->peer.ecn_capable)
323 sctp_addto_chunk(retval, sizeof(ecap_param), &ecap_param);
324 if (asoc->peer.prsctp_capable)
325 sctp_addto_chunk(retval, sizeof(prsctp_param), &prsctp_param);
327 aiparam.param_hdr.type = SCTP_PARAM_ADAPTION_LAYER_IND;
328 aiparam.param_hdr.length = htons(sizeof(aiparam));
329 aiparam.adaption_ind = htonl(sctp_sk(asoc->base.sk)->adaption_ind);
330 sctp_addto_chunk(retval, sizeof(aiparam), &aiparam);
332 /* We need to remove the const qualifier at this point. */
333 retval->asoc = (struct sctp_association *) asoc;
335 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
337 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
338 * HEARTBEAT ACK, * etc.) to the same destination transport
339 * address from which it received the DATA or control chunk
340 * to which it is replying.
342 * [INIT ACK back to where the INIT came from.]
345 retval->transport = chunk->transport;
355 /* 3.3.11 Cookie Echo (COOKIE ECHO) (10):
357 * This chunk is used only during the initialization of an association.
358 * It is sent by the initiator of an association to its peer to complete
359 * the initialization process. This chunk MUST precede any DATA chunk
360 * sent within the association, but MAY be bundled with one or more DATA
361 * chunks in the same packet.
364 * 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
365 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
366 * | Type = 10 |Chunk Flags | Length |
367 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
370 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
374 * Set to zero on transmit and ignored on receipt.
376 * Length: 16 bits (unsigned integer)
378 * Set to the size of the chunk in bytes, including the 4 bytes of
379 * the chunk header and the size of the Cookie.
381 * Cookie: variable size
383 * This field must contain the exact cookie received in the
384 * State Cookie parameter from the previous INIT ACK.
386 * An implementation SHOULD make the cookie as small as possible
387 * to insure interoperability.
389 struct sctp_chunk *sctp_make_cookie_echo(const struct sctp_association *asoc,
390 const struct sctp_chunk *chunk)
392 struct sctp_chunk *retval;
396 cookie = asoc->peer.cookie;
397 cookie_len = asoc->peer.cookie_len;
399 /* Build a cookie echo chunk. */
400 retval = sctp_make_chunk(asoc, SCTP_CID_COOKIE_ECHO, 0, cookie_len);
403 retval->subh.cookie_hdr =
404 sctp_addto_chunk(retval, cookie_len, cookie);
406 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
408 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
409 * HEARTBEAT ACK, * etc.) to the same destination transport
410 * address from which it * received the DATA or control chunk
411 * to which it is replying.
413 * [COOKIE ECHO back to where the INIT ACK came from.]
416 retval->transport = chunk->transport;
422 /* 3.3.12 Cookie Acknowledgement (COOKIE ACK) (11):
424 * This chunk is used only during the initialization of an
425 * association. It is used to acknowledge the receipt of a COOKIE
426 * ECHO chunk. This chunk MUST precede any DATA or SACK chunk sent
427 * within the association, but MAY be bundled with one or more DATA
428 * chunks or SACK chunk in the same SCTP packet.
431 * 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
432 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
433 * | Type = 11 |Chunk Flags | Length = 4 |
434 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
436 * Chunk Flags: 8 bits
438 * Set to zero on transmit and ignored on receipt.
440 struct sctp_chunk *sctp_make_cookie_ack(const struct sctp_association *asoc,
441 const struct sctp_chunk *chunk)
443 struct sctp_chunk *retval;
445 retval = sctp_make_chunk(asoc, SCTP_CID_COOKIE_ACK, 0, 0);
447 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
449 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
450 * HEARTBEAT ACK, * etc.) to the same destination transport
451 * address from which it * received the DATA or control chunk
452 * to which it is replying.
454 * [COOKIE ACK back to where the COOKIE ECHO came from.]
457 retval->transport = chunk->transport;
463 * Appendix A: Explicit Congestion Notification:
466 * RFC 2481 details a specific bit for a sender to send in the header of
467 * its next outbound TCP segment to indicate to its peer that it has
468 * reduced its congestion window. This is termed the CWR bit. For
469 * SCTP the same indication is made by including the CWR chunk.
470 * This chunk contains one data element, i.e. the TSN number that
471 * was sent in the ECNE chunk. This element represents the lowest
472 * TSN number in the datagram that was originally marked with the
476 * 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
477 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
478 * | Chunk Type=13 | Flags=00000000| Chunk Length = 8 |
479 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
480 * | Lowest TSN Number |
481 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
483 * Note: The CWR is considered a Control chunk.
485 struct sctp_chunk *sctp_make_cwr(const struct sctp_association *asoc,
486 const __u32 lowest_tsn,
487 const struct sctp_chunk *chunk)
489 struct sctp_chunk *retval;
492 cwr.lowest_tsn = htonl(lowest_tsn);
493 retval = sctp_make_chunk(asoc, SCTP_CID_ECN_CWR, 0,
494 sizeof(sctp_cwrhdr_t));
499 retval->subh.ecn_cwr_hdr =
500 sctp_addto_chunk(retval, sizeof(cwr), &cwr);
502 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
504 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
505 * HEARTBEAT ACK, * etc.) to the same destination transport
506 * address from which it * received the DATA or control chunk
507 * to which it is replying.
509 * [Report a reduced congestion window back to where the ECNE
513 retval->transport = chunk->transport;
519 /* Make an ECNE chunk. This is a congestion experienced report. */
520 struct sctp_chunk *sctp_make_ecne(const struct sctp_association *asoc,
521 const __u32 lowest_tsn)
523 struct sctp_chunk *retval;
526 ecne.lowest_tsn = htonl(lowest_tsn);
527 retval = sctp_make_chunk(asoc, SCTP_CID_ECN_ECNE, 0,
528 sizeof(sctp_ecnehdr_t));
531 retval->subh.ecne_hdr =
532 sctp_addto_chunk(retval, sizeof(ecne), &ecne);
538 /* Make a DATA chunk for the given association from the provided
539 * parameters. However, do not populate the data payload.
541 struct sctp_chunk *sctp_make_datafrag_empty(struct sctp_association *asoc,
542 const struct sctp_sndrcvinfo *sinfo,
543 int data_len, __u8 flags, __u16 ssn)
545 struct sctp_chunk *retval;
546 struct sctp_datahdr dp;
549 /* We assign the TSN as LATE as possible, not here when
550 * creating the chunk.
553 dp.stream = htons(sinfo->sinfo_stream);
554 dp.ppid = sinfo->sinfo_ppid;
556 /* Set the flags for an unordered send. */
557 if (sinfo->sinfo_flags & MSG_UNORDERED) {
558 flags |= SCTP_DATA_UNORDERED;
563 chunk_len = sizeof(dp) + data_len;
564 retval = sctp_make_chunk(asoc, SCTP_CID_DATA, flags, chunk_len);
568 retval->subh.data_hdr = sctp_addto_chunk(retval, sizeof(dp), &dp);
569 memcpy(&retval->sinfo, sinfo, sizeof(struct sctp_sndrcvinfo));
575 /* Create a selective ackowledgement (SACK) for the given
576 * association. This reports on which TSN's we've seen to date,
577 * including duplicates and gaps.
579 struct sctp_chunk *sctp_make_sack(const struct sctp_association *asoc)
581 struct sctp_chunk *retval;
582 struct sctp_sackhdr sack;
585 __u16 num_gabs, num_dup_tsns;
586 struct sctp_tsnmap *map = (struct sctp_tsnmap *)&asoc->peer.tsn_map;
588 ctsn = sctp_tsnmap_get_ctsn(map);
589 SCTP_DEBUG_PRINTK("sackCTSNAck sent: 0x%x.\n", ctsn);
591 /* How much room is needed in the chunk? */
592 num_gabs = sctp_tsnmap_num_gabs(map);
593 num_dup_tsns = sctp_tsnmap_num_dups(map);
595 /* Initialize the SACK header. */
596 sack.cum_tsn_ack = htonl(ctsn);
597 sack.a_rwnd = htonl(asoc->a_rwnd);
598 sack.num_gap_ack_blocks = htons(num_gabs);
599 sack.num_dup_tsns = htons(num_dup_tsns);
602 + sizeof(struct sctp_gap_ack_block) * num_gabs
603 + sizeof(__u32) * num_dup_tsns;
605 /* Create the chunk. */
606 retval = sctp_make_chunk(asoc, SCTP_CID_SACK, 0, len);
610 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
612 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
613 * HEARTBEAT ACK, etc.) to the same destination transport
614 * address from which it received the DATA or control chunk to
615 * which it is replying. This rule should also be followed if
616 * the endpoint is bundling DATA chunks together with the
619 * However, when acknowledging multiple DATA chunks received
620 * in packets from different source addresses in a single
621 * SACK, the SACK chunk may be transmitted to one of the
622 * destination transport addresses from which the DATA or
623 * control chunks being acknowledged were received.
625 * [BUG: We do not implement the following paragraph.
626 * Perhaps we should remember the last transport we used for a
627 * SACK and avoid that (if possible) if we have seen any
628 * duplicates. --piggy]
630 * When a receiver of a duplicate DATA chunk sends a SACK to a
631 * multi- homed endpoint it MAY be beneficial to vary the
632 * destination address and not use the source address of the
633 * DATA chunk. The reason being that receiving a duplicate
634 * from a multi-homed endpoint might indicate that the return
635 * path (as specified in the source address of the DATA chunk)
636 * for the SACK is broken.
638 * [Send to the address from which we last received a DATA chunk.]
640 retval->transport = asoc->peer.last_data_from;
642 retval->subh.sack_hdr =
643 sctp_addto_chunk(retval, sizeof(sack), &sack);
645 /* Add the gap ack block information. */
647 sctp_addto_chunk(retval, sizeof(__u32) * num_gabs,
648 sctp_tsnmap_get_gabs(map));
650 /* Add the duplicate TSN information. */
652 sctp_addto_chunk(retval, sizeof(__u32) * num_dup_tsns,
653 sctp_tsnmap_get_dups(map));
659 /* Make a SHUTDOWN chunk. */
660 struct sctp_chunk *sctp_make_shutdown(const struct sctp_association *asoc,
661 const struct sctp_chunk *chunk)
663 struct sctp_chunk *retval;
664 sctp_shutdownhdr_t shut;
667 ctsn = sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map);
668 shut.cum_tsn_ack = htonl(ctsn);
670 retval = sctp_make_chunk(asoc, SCTP_CID_SHUTDOWN, 0,
671 sizeof(sctp_shutdownhdr_t));
675 retval->subh.shutdown_hdr =
676 sctp_addto_chunk(retval, sizeof(shut), &shut);
679 retval->transport = chunk->transport;
684 struct sctp_chunk *sctp_make_shutdown_ack(const struct sctp_association *asoc,
685 const struct sctp_chunk *chunk)
687 struct sctp_chunk *retval;
689 retval = sctp_make_chunk(asoc, SCTP_CID_SHUTDOWN_ACK, 0, 0);
691 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
693 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
694 * HEARTBEAT ACK, * etc.) to the same destination transport
695 * address from which it * received the DATA or control chunk
696 * to which it is replying.
698 * [ACK back to where the SHUTDOWN came from.]
701 retval->transport = chunk->transport;
706 struct sctp_chunk *sctp_make_shutdown_complete(
707 const struct sctp_association *asoc,
708 const struct sctp_chunk *chunk)
710 struct sctp_chunk *retval;
713 /* Maybe set the T-bit if we have no association. */
714 flags |= asoc ? 0 : SCTP_CHUNK_FLAG_T;
716 retval = sctp_make_chunk(asoc, SCTP_CID_SHUTDOWN_COMPLETE, flags, 0);
718 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
720 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
721 * HEARTBEAT ACK, * etc.) to the same destination transport
722 * address from which it * received the DATA or control chunk
723 * to which it is replying.
725 * [Report SHUTDOWN COMPLETE back to where the SHUTDOWN ACK
729 retval->transport = chunk->transport;
734 /* Create an ABORT. Note that we set the T bit if we have no
737 struct sctp_chunk *sctp_make_abort(const struct sctp_association *asoc,
738 const struct sctp_chunk *chunk,
741 struct sctp_chunk *retval;
744 /* Maybe set the T-bit if we have no association. */
745 flags |= asoc ? 0 : SCTP_CHUNK_FLAG_T;
747 retval = sctp_make_chunk(asoc, SCTP_CID_ABORT, flags, hint);
749 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
751 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
752 * HEARTBEAT ACK, * etc.) to the same destination transport
753 * address from which it * received the DATA or control chunk
754 * to which it is replying.
756 * [ABORT back to where the offender came from.]
759 retval->transport = chunk->transport;
764 /* Helper to create ABORT with a NO_USER_DATA error. */
765 struct sctp_chunk *sctp_make_abort_no_data(
766 const struct sctp_association *asoc,
767 const struct sctp_chunk *chunk, __u32 tsn)
769 struct sctp_chunk *retval;
772 retval = sctp_make_abort(asoc, chunk, sizeof(sctp_errhdr_t)
778 /* Put the tsn back into network byte order. */
779 payload = htonl(tsn);
780 sctp_init_cause(retval, SCTP_ERROR_NO_DATA, (const void *)&payload,
783 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
785 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
786 * HEARTBEAT ACK, * etc.) to the same destination transport
787 * address from which it * received the DATA or control chunk
788 * to which it is replying.
790 * [ABORT back to where the offender came from.]
793 retval->transport = chunk->transport;
799 /* Helper to create ABORT with a SCTP_ERROR_USER_ABORT error. */
800 struct sctp_chunk *sctp_make_abort_user(const struct sctp_association *asoc,
801 const struct msghdr *msg,
804 struct sctp_chunk *retval;
805 void *payload = NULL;
808 retval = sctp_make_abort(asoc, NULL, sizeof(sctp_errhdr_t) + paylen);
813 /* Put the msg_iov together into payload. */
814 payload = kmalloc(paylen, GFP_KERNEL);
818 err = memcpy_fromiovec(payload, msg->msg_iov, paylen);
823 sctp_init_cause(retval, SCTP_ERROR_USER_ABORT, payload, paylen);
833 sctp_chunk_free(retval);
839 /* Make an ABORT chunk with a PROTOCOL VIOLATION cause code. */
840 struct sctp_chunk *sctp_make_abort_violation(
841 const struct sctp_association *asoc,
842 const struct sctp_chunk *chunk,
846 struct sctp_chunk *retval;
847 struct sctp_paramhdr phdr;
849 retval = sctp_make_abort(asoc, chunk, sizeof(sctp_errhdr_t) + paylen
850 + sizeof(sctp_chunkhdr_t));
854 sctp_init_cause(retval, SCTP_ERROR_PROTO_VIOLATION, payload, paylen);
856 phdr.type = htons(chunk->chunk_hdr->type);
857 phdr.length = chunk->chunk_hdr->length;
858 sctp_addto_chunk(retval, sizeof(sctp_paramhdr_t), &phdr);
864 /* Make a HEARTBEAT chunk. */
865 struct sctp_chunk *sctp_make_heartbeat(const struct sctp_association *asoc,
866 const struct sctp_transport *transport,
867 const void *payload, const size_t paylen)
869 struct sctp_chunk *retval = sctp_make_chunk(asoc, SCTP_CID_HEARTBEAT,
875 /* Cast away the 'const', as this is just telling the chunk
876 * what transport it belongs to.
878 retval->transport = (struct sctp_transport *) transport;
879 retval->subh.hbs_hdr = sctp_addto_chunk(retval, paylen, payload);
885 struct sctp_chunk *sctp_make_heartbeat_ack(const struct sctp_association *asoc,
886 const struct sctp_chunk *chunk,
887 const void *payload, const size_t paylen)
889 struct sctp_chunk *retval;
891 retval = sctp_make_chunk(asoc, SCTP_CID_HEARTBEAT_ACK, 0, paylen);
895 retval->subh.hbs_hdr = sctp_addto_chunk(retval, paylen, payload);
897 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
899 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
900 * HEARTBEAT ACK, * etc.) to the same destination transport
901 * address from which it * received the DATA or control chunk
902 * to which it is replying.
904 * [HBACK back to where the HEARTBEAT came from.]
907 retval->transport = chunk->transport;
913 /* Create an Operation Error chunk with the specified space reserved.
914 * This routine can be used for containing multiple causes in the chunk.
916 static struct sctp_chunk *sctp_make_op_error_space(
917 const struct sctp_association *asoc,
918 const struct sctp_chunk *chunk,
921 struct sctp_chunk *retval;
923 retval = sctp_make_chunk(asoc, SCTP_CID_ERROR, 0,
924 sizeof(sctp_errhdr_t) + size);
928 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
930 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
931 * HEARTBEAT ACK, etc.) to the same destination transport
932 * address from which it received the DATA or control chunk
933 * to which it is replying.
937 retval->transport = chunk->transport;
943 /* Create an Operation Error chunk. */
944 struct sctp_chunk *sctp_make_op_error(const struct sctp_association *asoc,
945 const struct sctp_chunk *chunk,
946 __u16 cause_code, const void *payload,
949 struct sctp_chunk *retval;
951 retval = sctp_make_op_error_space(asoc, chunk, paylen);
955 sctp_init_cause(retval, cause_code, payload, paylen);
961 /********************************************************************
962 * 2nd Level Abstractions
963 ********************************************************************/
965 /* Turn an skb into a chunk.
966 * FIXME: Eventually move the structure directly inside the skb->cb[].
968 struct sctp_chunk *sctp_chunkify(struct sk_buff *skb,
969 const struct sctp_association *asoc,
972 struct sctp_chunk *retval;
974 retval = kmem_cache_alloc(sctp_chunk_cachep, SLAB_ATOMIC);
978 memset(retval, 0, sizeof(struct sctp_chunk));
981 SCTP_DEBUG_PRINTK("chunkifying skb %p w/o an sk\n", skb);
985 retval->asoc = (struct sctp_association *)asoc;
989 retval->rtt_in_progress = 0;
991 retval->singleton = 1;
992 retval->end_of_packet = 0;
993 retval->ecn_ce_done = 0;
994 retval->pdiscard = 0;
996 /* sctpimpguide-05.txt Section 2.8.2
997 * M1) Each time a new DATA chunk is transmitted
998 * set the 'TSN.Missing.Report' count for that TSN to 0. The
999 * 'TSN.Missing.Report' count will be used to determine missing chunks
1000 * and when to fast retransmit.
1002 retval->tsn_missing_report = 0;
1003 retval->tsn_gap_acked = 0;
1004 retval->fast_retransmit = 0;
1006 /* If this is a fragmented message, track all fragments
1007 * of the message (for SEND_FAILED).
1011 /* Polish the bead hole. */
1012 INIT_LIST_HEAD(&retval->transmitted_list);
1013 INIT_LIST_HEAD(&retval->frag_list);
1014 SCTP_DBG_OBJCNT_INC(chunk);
1015 atomic_set(&retval->refcnt, 1);
1021 /* Set chunk->source and dest based on the IP header in chunk->skb. */
1022 void sctp_init_addrs(struct sctp_chunk *chunk, union sctp_addr *src,
1023 union sctp_addr *dest)
1025 memcpy(&chunk->source, src, sizeof(union sctp_addr));
1026 memcpy(&chunk->dest, dest, sizeof(union sctp_addr));
1029 /* Extract the source address from a chunk. */
1030 const union sctp_addr *sctp_source(const struct sctp_chunk *chunk)
1032 /* If we have a known transport, use that. */
1033 if (chunk->transport) {
1034 return &chunk->transport->ipaddr;
1036 /* Otherwise, extract it from the IP header. */
1037 return &chunk->source;
1041 /* Create a new chunk, setting the type and flags headers from the
1042 * arguments, reserving enough space for a 'paylen' byte payload.
1045 struct sctp_chunk *sctp_make_chunk(const struct sctp_association *asoc,
1046 __u8 type, __u8 flags, int paylen)
1048 struct sctp_chunk *retval;
1049 sctp_chunkhdr_t *chunk_hdr;
1050 struct sk_buff *skb;
1053 /* No need to allocate LL here, as this is only a chunk. */
1054 skb = alloc_skb(WORD_ROUND(sizeof(sctp_chunkhdr_t) + paylen),
1059 /* Make room for the chunk header. */
1060 chunk_hdr = (sctp_chunkhdr_t *)skb_put(skb, sizeof(sctp_chunkhdr_t));
1061 chunk_hdr->type = type;
1062 chunk_hdr->flags = flags;
1063 chunk_hdr->length = htons(sizeof(sctp_chunkhdr_t));
1065 sk = asoc ? asoc->base.sk : NULL;
1066 retval = sctp_chunkify(skb, asoc, sk);
1072 retval->chunk_hdr = chunk_hdr;
1073 retval->chunk_end = ((__u8 *)chunk_hdr) + sizeof(struct sctp_chunkhdr);
1075 /* Set the skb to the belonging sock for accounting. */
1084 /* Release the memory occupied by a chunk. */
1085 static void sctp_chunk_destroy(struct sctp_chunk *chunk)
1087 /* Free the chunk skb data and the SCTP_chunk stub itself. */
1088 dev_kfree_skb(chunk->skb);
1090 SCTP_DBG_OBJCNT_DEC(chunk);
1091 kmem_cache_free(sctp_chunk_cachep, chunk);
1094 /* Possibly, free the chunk. */
1095 void sctp_chunk_free(struct sctp_chunk *chunk)
1097 /* Make sure that we are not on any list. */
1098 skb_unlink((struct sk_buff *) chunk);
1099 list_del_init(&chunk->transmitted_list);
1101 /* Release our reference on the message tracker. */
1103 sctp_datamsg_put(chunk->msg);
1105 sctp_chunk_put(chunk);
1108 /* Grab a reference to the chunk. */
1109 void sctp_chunk_hold(struct sctp_chunk *ch)
1111 atomic_inc(&ch->refcnt);
1114 /* Release a reference to the chunk. */
1115 void sctp_chunk_put(struct sctp_chunk *ch)
1117 if (atomic_dec_and_test(&ch->refcnt))
1118 sctp_chunk_destroy(ch);
1121 /* Append bytes to the end of a chunk. Will panic if chunk is not big
1124 void *sctp_addto_chunk(struct sctp_chunk *chunk, int len, const void *data)
1128 int chunklen = ntohs(chunk->chunk_hdr->length);
1129 int padlen = chunklen % 4;
1131 padding = skb_put(chunk->skb, padlen);
1132 target = skb_put(chunk->skb, len);
1134 memset(padding, 0, padlen);
1135 memcpy(target, data, len);
1137 /* Adjust the chunk length field. */
1138 chunk->chunk_hdr->length = htons(chunklen + padlen + len);
1139 chunk->chunk_end = chunk->skb->tail;
1144 /* Append bytes from user space to the end of a chunk. Will panic if
1145 * chunk is not big enough.
1146 * Returns a kernel err value.
1148 int sctp_user_addto_chunk(struct sctp_chunk *chunk, int off, int len,
1154 /* Make room in chunk for data. */
1155 target = skb_put(chunk->skb, len);
1157 /* Copy data (whole iovec) into chunk */
1158 if ((err = memcpy_fromiovecend(target, data, off, len)))
1161 /* Adjust the chunk length field. */
1162 chunk->chunk_hdr->length =
1163 htons(ntohs(chunk->chunk_hdr->length) + len);
1164 chunk->chunk_end = chunk->skb->tail;
1170 /* Helper function to assign a TSN if needed. This assumes that both
1171 * the data_hdr and association have already been assigned.
1173 void sctp_chunk_assign_ssn(struct sctp_chunk *chunk)
1181 /* This is the last possible instant to assign a SSN. */
1182 if (chunk->chunk_hdr->flags & SCTP_DATA_UNORDERED) {
1185 sid = htons(chunk->subh.data_hdr->stream);
1186 if (chunk->chunk_hdr->flags & SCTP_DATA_LAST_FRAG)
1187 ssn = sctp_ssn_next(&chunk->asoc->ssnmap->out, sid);
1189 ssn = sctp_ssn_peek(&chunk->asoc->ssnmap->out, sid);
1193 chunk->subh.data_hdr->ssn = ssn;
1197 /* Helper function to assign a TSN if needed. This assumes that both
1198 * the data_hdr and association have already been assigned.
1200 void sctp_chunk_assign_tsn(struct sctp_chunk *chunk)
1202 if (!chunk->has_tsn) {
1203 /* This is the last possible instant to
1206 chunk->subh.data_hdr->tsn =
1207 htonl(sctp_association_get_next_tsn(chunk->asoc));
1212 /* Create a CLOSED association to use with an incoming packet. */
1213 struct sctp_association *sctp_make_temp_asoc(const struct sctp_endpoint *ep,
1214 struct sctp_chunk *chunk, int gfp)
1216 struct sctp_association *asoc;
1217 struct sk_buff *skb;
1221 /* Create the bare association. */
1222 scope = sctp_scope(sctp_source(chunk));
1223 asoc = sctp_association_new(ep, ep->base.sk, scope, gfp);
1228 /* Create an entry for the source address of the packet. */
1229 af = sctp_get_af_specific(ipver2af(skb->nh.iph->version));
1232 af->from_skb(&asoc->c.peer_addr, skb, 1);
1237 sctp_association_free(asoc);
1241 /* Build a cookie representing asoc.
1242 * This INCLUDES the param header needed to put the cookie in the INIT ACK.
1244 static sctp_cookie_param_t *sctp_pack_cookie(const struct sctp_endpoint *ep,
1245 const struct sctp_association *asoc,
1246 const struct sctp_chunk *init_chunk,
1248 const __u8 *raw_addrs, int addrs_len)
1250 sctp_cookie_param_t *retval;
1251 struct sctp_signed_cookie *cookie;
1252 struct scatterlist sg;
1253 int headersize, bodysize;
1254 unsigned int keylen;
1257 headersize = sizeof(sctp_paramhdr_t) + SCTP_SECRET_SIZE;
1258 bodysize = sizeof(struct sctp_cookie)
1259 + ntohs(init_chunk->chunk_hdr->length) + addrs_len;
1261 /* Pad out the cookie to a multiple to make the signature
1262 * functions simpler to write.
1264 if (bodysize % SCTP_COOKIE_MULTIPLE)
1265 bodysize += SCTP_COOKIE_MULTIPLE
1266 - (bodysize % SCTP_COOKIE_MULTIPLE);
1267 *cookie_len = headersize + bodysize;
1269 retval = (sctp_cookie_param_t *)kmalloc(*cookie_len, GFP_ATOMIC);
1276 /* Clear this memory since we are sending this data structure
1277 * out on the network.
1279 memset(retval, 0x00, *cookie_len);
1280 cookie = (struct sctp_signed_cookie *) retval->body;
1282 /* Set up the parameter header. */
1283 retval->p.type = SCTP_PARAM_STATE_COOKIE;
1284 retval->p.length = htons(*cookie_len);
1286 /* Copy the cookie part of the association itself. */
1287 cookie->c = asoc->c;
1288 /* Save the raw address list length in the cookie. */
1289 cookie->c.raw_addr_list_len = addrs_len;
1291 /* Remember PR-SCTP capability. */
1292 cookie->c.prsctp_capable = asoc->peer.prsctp_capable;
1294 /* Save adaption indication in the cookie. */
1295 cookie->c.adaption_ind = asoc->peer.adaption_ind;
1297 /* Set an expiration time for the cookie. */
1298 do_gettimeofday(&cookie->c.expiration);
1299 TIMEVAL_ADD(asoc->cookie_life, cookie->c.expiration);
1301 /* Copy the peer's init packet. */
1302 memcpy(&cookie->c.peer_init[0], init_chunk->chunk_hdr,
1303 ntohs(init_chunk->chunk_hdr->length));
1305 /* Copy the raw local address list of the association. */
1306 memcpy((__u8 *)&cookie->c.peer_init[0] +
1307 ntohs(init_chunk->chunk_hdr->length), raw_addrs, addrs_len);
1309 if (sctp_sk(ep->base.sk)->hmac) {
1310 /* Sign the message. */
1311 sg.page = virt_to_page(&cookie->c);
1312 sg.offset = (unsigned long)(&cookie->c) % PAGE_SIZE;
1313 sg.length = bodysize;
1314 keylen = SCTP_SECRET_SIZE;
1315 key = (char *)ep->secret_key[ep->current_key];
1317 sctp_crypto_hmac(sctp_sk(ep->base.sk)->hmac, key, &keylen,
1318 &sg, 1, cookie->signature);
1325 /* Unpack the cookie from COOKIE ECHO chunk, recreating the association. */
1326 struct sctp_association *sctp_unpack_cookie(
1327 const struct sctp_endpoint *ep,
1328 const struct sctp_association *asoc,
1329 struct sctp_chunk *chunk, int gfp,
1330 int *error, struct sctp_chunk **errp)
1332 struct sctp_association *retval = NULL;
1333 struct sctp_signed_cookie *cookie;
1334 struct sctp_cookie *bear_cookie;
1335 int headersize, bodysize, fixed_size;
1336 __u8 digest[SCTP_SIGNATURE_SIZE];
1337 struct scatterlist sg;
1338 unsigned int keylen, len;
1341 struct sk_buff *skb = chunk->skb;
1343 headersize = sizeof(sctp_chunkhdr_t) + SCTP_SECRET_SIZE;
1344 bodysize = ntohs(chunk->chunk_hdr->length) - headersize;
1345 fixed_size = headersize + sizeof(struct sctp_cookie);
1347 /* Verify that the chunk looks like it even has a cookie.
1348 * There must be enough room for our cookie and our peer's
1351 len = ntohs(chunk->chunk_hdr->length);
1352 if (len < fixed_size + sizeof(struct sctp_chunkhdr))
1355 /* Verify that the cookie has been padded out. */
1356 if (bodysize % SCTP_COOKIE_MULTIPLE)
1359 /* Process the cookie. */
1360 cookie = chunk->subh.cookie_hdr;
1361 bear_cookie = &cookie->c;
1363 if (!sctp_sk(ep->base.sk)->hmac)
1366 /* Check the signature. */
1367 keylen = SCTP_SECRET_SIZE;
1368 sg.page = virt_to_page(bear_cookie);
1369 sg.offset = (unsigned long)(bear_cookie) % PAGE_SIZE;
1370 sg.length = bodysize;
1371 key = (char *)ep->secret_key[ep->current_key];
1373 memset(digest, 0x00, sizeof(digest));
1374 sctp_crypto_hmac(sctp_sk(ep->base.sk)->hmac, key, &keylen, &sg,
1377 if (memcmp(digest, cookie->signature, SCTP_SIGNATURE_SIZE)) {
1378 /* Try the previous key. */
1379 key = (char *)ep->secret_key[ep->last_key];
1380 memset(digest, 0x00, sizeof(digest));
1381 sctp_crypto_hmac(sctp_sk(ep->base.sk)->hmac, key, &keylen,
1384 if (memcmp(digest, cookie->signature, SCTP_SIGNATURE_SIZE)) {
1385 /* Yikes! Still bad signature! */
1386 *error = -SCTP_IERROR_BAD_SIG;
1392 /* IG Section 2.35.2:
1393 * 3) Compare the port numbers and the verification tag contained
1394 * within the COOKIE ECHO chunk to the actual port numbers and the
1395 * verification tag within the SCTP common header of the received
1396 * packet. If these values do not match the packet MUST be silently
1399 if (ntohl(chunk->sctp_hdr->vtag) != bear_cookie->my_vtag) {
1400 *error = -SCTP_IERROR_BAD_TAG;
1404 if (ntohs(chunk->sctp_hdr->source) != bear_cookie->peer_addr.v4.sin_port ||
1405 ntohs(chunk->sctp_hdr->dest) != bear_cookie->my_port) {
1406 *error = -SCTP_IERROR_BAD_PORTS;
1410 /* Check to see if the cookie is stale. If there is already
1411 * an association, there is no need to check cookie's expiration
1412 * for init collision case of lost COOKIE ACK.
1414 if (!asoc && tv_lt(bear_cookie->expiration, skb->stamp)) {
1417 * Section 3.3.10.3 Stale Cookie Error (3)
1421 * Stale Cookie Error: Indicates the receipt of a valid State
1422 * Cookie that has expired.
1424 len = ntohs(chunk->chunk_hdr->length);
1425 *errp = sctp_make_op_error_space(asoc, chunk, len);
1427 suseconds_t usecs = (skb->stamp.tv_sec -
1428 bear_cookie->expiration.tv_sec) * 1000000L +
1429 skb->stamp.tv_usec -
1430 bear_cookie->expiration.tv_usec;
1432 usecs = htonl(usecs);
1433 sctp_init_cause(*errp, SCTP_ERROR_STALE_COOKIE,
1434 &usecs, sizeof(usecs));
1435 *error = -SCTP_IERROR_STALE_COOKIE;
1437 *error = -SCTP_IERROR_NOMEM;
1442 /* Make a new base association. */
1443 scope = sctp_scope(sctp_source(chunk));
1444 retval = sctp_association_new(ep, ep->base.sk, scope, gfp);
1446 *error = -SCTP_IERROR_NOMEM;
1450 /* Set up our peer's port number. */
1451 retval->peer.port = ntohs(chunk->sctp_hdr->source);
1453 /* Populate the association from the cookie. */
1454 memcpy(&retval->c, bear_cookie, sizeof(*bear_cookie));
1456 if (sctp_assoc_set_bind_addr_from_cookie(retval, bear_cookie,
1458 *error = -SCTP_IERROR_NOMEM;
1462 /* Also, add the destination address. */
1463 if (list_empty(&retval->base.bind_addr.address_list)) {
1464 sctp_add_bind_addr(&retval->base.bind_addr, &chunk->dest,
1468 retval->next_tsn = retval->c.initial_tsn;
1469 retval->ctsn_ack_point = retval->next_tsn - 1;
1470 retval->addip_serial = retval->c.initial_tsn;
1471 retval->adv_peer_ack_point = retval->ctsn_ack_point;
1472 retval->peer.prsctp_capable = retval->c.prsctp_capable;
1473 retval->peer.adaption_ind = retval->c.adaption_ind;
1475 /* The INIT stuff will be done by the side effects. */
1480 sctp_association_free(retval);
1485 /* Yikes! The packet is either corrupt or deliberately
1488 *error = -SCTP_IERROR_MALFORMED;
1492 /********************************************************************
1493 * 3rd Level Abstractions
1494 ********************************************************************/
1496 struct __sctp_missing {
1499 } __attribute__((packed));;
1502 * Report a missing mandatory parameter.
1504 static int sctp_process_missing_param(const struct sctp_association *asoc,
1505 sctp_param_t paramtype,
1506 struct sctp_chunk *chunk,
1507 struct sctp_chunk **errp)
1509 struct __sctp_missing report;
1512 len = WORD_ROUND(sizeof(report));
1514 /* Make an ERROR chunk, preparing enough room for
1515 * returning multiple unknown parameters.
1518 *errp = sctp_make_op_error_space(asoc, chunk, len);
1521 report.num_missing = htonl(1);
1522 report.type = paramtype;
1523 sctp_init_cause(*errp, SCTP_ERROR_INV_PARAM,
1524 &report, sizeof(report));
1527 /* Stop processing this chunk. */
1531 /* Report an Invalid Mandatory Parameter. */
1532 static int sctp_process_inv_mandatory(const struct sctp_association *asoc,
1533 struct sctp_chunk *chunk,
1534 struct sctp_chunk **errp)
1536 /* Invalid Mandatory Parameter Error has no payload. */
1539 *errp = sctp_make_op_error_space(asoc, chunk, 0);
1542 sctp_init_cause(*errp, SCTP_ERROR_INV_PARAM, NULL, 0);
1544 /* Stop processing this chunk. */
1548 static int sctp_process_inv_paramlength(const struct sctp_association *asoc,
1549 struct sctp_paramhdr *param,
1550 const struct sctp_chunk *chunk,
1551 struct sctp_chunk **errp)
1553 char error[] = "The following parameter had invalid length:";
1554 size_t payload_len = WORD_ROUND(sizeof(error)) +
1555 sizeof(sctp_paramhdr_t);
1558 /* Create an error chunk and fill it in with our payload. */
1560 *errp = sctp_make_op_error_space(asoc, chunk, payload_len);
1563 sctp_init_cause(*errp, SCTP_ERROR_PROTO_VIOLATION, error,
1565 sctp_addto_chunk(*errp, sizeof(sctp_paramhdr_t), param);
1572 /* Do not attempt to handle the HOST_NAME parm. However, do
1573 * send back an indicator to the peer.
1575 static int sctp_process_hn_param(const struct sctp_association *asoc,
1576 union sctp_params param,
1577 struct sctp_chunk *chunk,
1578 struct sctp_chunk **errp)
1580 __u16 len = ntohs(param.p->length);
1582 /* Make an ERROR chunk. */
1584 *errp = sctp_make_op_error_space(asoc, chunk, len);
1587 sctp_init_cause(*errp, SCTP_ERROR_DNS_FAILED,
1590 /* Stop processing this chunk. */
1594 /* RFC 3.2.1 & the Implementers Guide 2.2.
1596 * The Parameter Types are encoded such that the
1597 * highest-order two bits specify the action that must be
1598 * taken if the processing endpoint does not recognize the
1601 * 00 - Stop processing this SCTP chunk and discard it,
1602 * do not process any further chunks within it.
1604 * 01 - Stop processing this SCTP chunk and discard it,
1605 * do not process any further chunks within it, and report
1606 * the unrecognized parameter in an 'Unrecognized
1607 * Parameter Type' (in either an ERROR or in the INIT ACK).
1609 * 10 - Skip this parameter and continue processing.
1611 * 11 - Skip this parameter and continue processing but
1612 * report the unrecognized parameter in an
1613 * 'Unrecognized Parameter Type' (in either an ERROR or in
1617 * 0 - discard the chunk
1618 * 1 - continue with the chunk
1620 static int sctp_process_unk_param(const struct sctp_association *asoc,
1621 union sctp_params param,
1622 struct sctp_chunk *chunk,
1623 struct sctp_chunk **errp)
1627 switch (param.p->type & SCTP_PARAM_ACTION_MASK) {
1628 case SCTP_PARAM_ACTION_DISCARD:
1631 case SCTP_PARAM_ACTION_DISCARD_ERR:
1633 /* Make an ERROR chunk, preparing enough room for
1634 * returning multiple unknown parameters.
1637 *errp = sctp_make_op_error_space(asoc, chunk,
1638 ntohs(chunk->chunk_hdr->length));
1641 sctp_init_cause(*errp, SCTP_ERROR_UNKNOWN_PARAM,
1643 WORD_ROUND(ntohs(param.p->length)));
1646 case SCTP_PARAM_ACTION_SKIP:
1648 case SCTP_PARAM_ACTION_SKIP_ERR:
1649 /* Make an ERROR chunk, preparing enough room for
1650 * returning multiple unknown parameters.
1653 *errp = sctp_make_op_error_space(asoc, chunk,
1654 ntohs(chunk->chunk_hdr->length));
1657 sctp_init_cause(*errp, SCTP_ERROR_UNKNOWN_PARAM,
1659 WORD_ROUND(ntohs(param.p->length)));
1661 /* If there is no memory for generating the ERROR
1662 * report as specified, an ABORT will be triggered
1663 * to the peer and the association won't be
1677 /* Find unrecognized parameters in the chunk.
1679 * 0 - discard the chunk
1680 * 1 - continue with the chunk
1682 static int sctp_verify_param(const struct sctp_association *asoc,
1683 union sctp_params param,
1685 struct sctp_chunk *chunk,
1686 struct sctp_chunk **err_chunk)
1690 /* FIXME - This routine is not looking at each parameter per the
1691 * chunk type, i.e., unrecognized parameters should be further
1692 * identified based on the chunk id.
1695 switch (param.p->type) {
1696 case SCTP_PARAM_IPV4_ADDRESS:
1697 case SCTP_PARAM_IPV6_ADDRESS:
1698 case SCTP_PARAM_COOKIE_PRESERVATIVE:
1699 case SCTP_PARAM_SUPPORTED_ADDRESS_TYPES:
1700 case SCTP_PARAM_STATE_COOKIE:
1701 case SCTP_PARAM_HEARTBEAT_INFO:
1702 case SCTP_PARAM_UNRECOGNIZED_PARAMETERS:
1703 case SCTP_PARAM_ECN_CAPABLE:
1704 case SCTP_PARAM_ADAPTION_LAYER_IND:
1707 case SCTP_PARAM_HOST_NAME_ADDRESS:
1708 /* Tell the peer, we won't support this param. */
1709 return sctp_process_hn_param(asoc, param, chunk, err_chunk);
1710 case SCTP_PARAM_FWD_TSN_SUPPORT:
1711 if (sctp_prsctp_enable)
1715 SCTP_DEBUG_PRINTK("Unrecognized param: %d for chunk %d.\n",
1716 ntohs(param.p->type), cid);
1717 return sctp_process_unk_param(asoc, param, chunk, err_chunk);
1724 /* Verify the INIT packet before we process it. */
1725 int sctp_verify_init(const struct sctp_association *asoc,
1727 sctp_init_chunk_t *peer_init,
1728 struct sctp_chunk *chunk,
1729 struct sctp_chunk **errp)
1731 union sctp_params param;
1734 /* Verify stream values are non-zero. */
1735 if ((0 == peer_init->init_hdr.num_outbound_streams) ||
1736 (0 == peer_init->init_hdr.num_inbound_streams)) {
1738 sctp_process_inv_mandatory(asoc, chunk, errp);
1742 /* Check for missing mandatory parameters. */
1743 sctp_walk_params(param, peer_init, init_hdr.params) {
1745 if (SCTP_PARAM_STATE_COOKIE == param.p->type)
1748 } /* for (loop through all parameters) */
1750 /* There is a possibility that a parameter length was bad and
1751 * in that case we would have stoped walking the parameters.
1752 * The current param.p would point at the bad one.
1753 * Current consensus on the mailing list is to generate a PROTOCOL
1754 * VIOLATION error. We build the ERROR chunk here and let the normal
1755 * error handling code build and send the packet.
1757 if (param.v < (void*)chunk->chunk_end - sizeof(sctp_paramhdr_t)) {
1758 sctp_process_inv_paramlength(asoc, param.p, chunk, errp);
1762 /* The only missing mandatory param possible today is
1763 * the state cookie for an INIT-ACK chunk.
1765 if ((SCTP_CID_INIT_ACK == cid) && !has_cookie) {
1766 sctp_process_missing_param(asoc, SCTP_PARAM_STATE_COOKIE,
1771 /* Find unrecognized parameters. */
1773 sctp_walk_params(param, peer_init, init_hdr.params) {
1775 if (!sctp_verify_param(asoc, param, cid, chunk, errp)) {
1776 if (SCTP_PARAM_HOST_NAME_ADDRESS == param.p->type)
1782 } /* for (loop through all parameters) */
1787 /* Unpack the parameters in an INIT packet into an association.
1788 * Returns 0 on failure, else success.
1789 * FIXME: This is an association method.
1791 int sctp_process_init(struct sctp_association *asoc, sctp_cid_t cid,
1792 const union sctp_addr *peer_addr,
1793 sctp_init_chunk_t *peer_init, int gfp)
1795 union sctp_params param;
1796 struct sctp_transport *transport;
1797 struct list_head *pos, *temp;
1800 /* We must include the address that the INIT packet came from.
1801 * This is the only address that matters for an INIT packet.
1802 * When processing a COOKIE ECHO, we retrieve the from address
1803 * of the INIT from the cookie.
1806 /* This implementation defaults to making the first transport
1807 * added as the primary transport. The source address seems to
1808 * be a a better choice than any of the embedded addresses.
1811 if(!sctp_assoc_add_peer(asoc, peer_addr, gfp))
1814 /* Process the initialization parameters. */
1816 sctp_walk_params(param, peer_init, init_hdr.params) {
1818 if (!sctp_process_param(asoc, param, peer_addr, gfp))
1822 /* The fixed INIT headers are always in network byte
1825 asoc->peer.i.init_tag =
1826 ntohl(peer_init->init_hdr.init_tag);
1827 asoc->peer.i.a_rwnd =
1828 ntohl(peer_init->init_hdr.a_rwnd);
1829 asoc->peer.i.num_outbound_streams =
1830 ntohs(peer_init->init_hdr.num_outbound_streams);
1831 asoc->peer.i.num_inbound_streams =
1832 ntohs(peer_init->init_hdr.num_inbound_streams);
1833 asoc->peer.i.initial_tsn =
1834 ntohl(peer_init->init_hdr.initial_tsn);
1836 /* Apply the upper bounds for output streams based on peer's
1837 * number of inbound streams.
1839 if (asoc->c.sinit_num_ostreams >
1840 ntohs(peer_init->init_hdr.num_inbound_streams)) {
1841 asoc->c.sinit_num_ostreams =
1842 ntohs(peer_init->init_hdr.num_inbound_streams);
1845 if (asoc->c.sinit_max_instreams >
1846 ntohs(peer_init->init_hdr.num_outbound_streams)) {
1847 asoc->c.sinit_max_instreams =
1848 ntohs(peer_init->init_hdr.num_outbound_streams);
1851 /* Copy Initiation tag from INIT to VT_peer in cookie. */
1852 asoc->c.peer_vtag = asoc->peer.i.init_tag;
1854 /* Peer Rwnd : Current calculated value of the peer's rwnd. */
1855 asoc->peer.rwnd = asoc->peer.i.a_rwnd;
1857 /* Copy cookie in case we need to resend COOKIE-ECHO. */
1858 cookie = asoc->peer.cookie;
1860 asoc->peer.cookie = kmalloc(asoc->peer.cookie_len, gfp);
1861 if (!asoc->peer.cookie)
1863 memcpy(asoc->peer.cookie, cookie, asoc->peer.cookie_len);
1866 /* RFC 2960 7.2.1 The initial value of ssthresh MAY be arbitrarily
1867 * high (for example, implementations MAY use the size of the receiver
1868 * advertised window).
1870 list_for_each(pos, &asoc->peer.transport_addr_list) {
1871 transport = list_entry(pos, struct sctp_transport, transports);
1872 transport->ssthresh = asoc->peer.i.a_rwnd;
1875 /* Set up the TSN tracking pieces. */
1876 sctp_tsnmap_init(&asoc->peer.tsn_map, SCTP_TSN_MAP_SIZE,
1877 asoc->peer.i.initial_tsn);
1879 /* RFC 2960 6.5 Stream Identifier and Stream Sequence Number
1881 * The stream sequence number in all the streams shall start
1882 * from 0 when the association is established. Also, when the
1883 * stream sequence number reaches the value 65535 the next
1884 * stream sequence number shall be set to 0.
1887 /* Allocate storage for the negotiated streams if it is not a temporary * association.
1890 asoc->ssnmap = sctp_ssnmap_new(asoc->c.sinit_max_instreams,
1891 asoc->c.sinit_num_ostreams, gfp);
1896 /* ADDIP Section 4.1 ASCONF Chunk Procedures
1898 * When an endpoint has an ASCONF signaled change to be sent to the
1899 * remote endpoint it should do the following:
1901 * A2) A serial number should be assigned to the Chunk. The serial
1902 * number should be a monotonically increasing number. All serial
1903 * numbers are defined to be initialized at the start of the
1904 * association to the same value as the Initial TSN.
1906 asoc->peer.addip_serial = asoc->peer.i.initial_tsn - 1;
1911 /* Release the transport structures. */
1912 list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
1913 transport = list_entry(pos, struct sctp_transport, transports);
1915 sctp_transport_free(transport);
1922 /* Update asoc with the option described in param.
1924 * RFC2960 3.3.2.1 Optional/Variable Length Parameters in INIT
1926 * asoc is the association to update.
1927 * param is the variable length parameter to use for update.
1928 * cid tells us if this is an INIT, INIT ACK or COOKIE ECHO.
1929 * If the current packet is an INIT we want to minimize the amount of
1930 * work we do. In particular, we should not build transport
1931 * structures for the addresses.
1933 static int sctp_process_param(struct sctp_association *asoc,
1934 union sctp_params param,
1935 const union sctp_addr *peer_addr,
1938 union sctp_addr addr;
1946 /* We maintain all INIT parameters in network byte order all the
1947 * time. This allows us to not worry about whether the parameters
1948 * came from a fresh INIT, and INIT ACK, or were stored in a cookie.
1950 switch (param.p->type) {
1951 case SCTP_PARAM_IPV6_ADDRESS:
1952 if (PF_INET6 != asoc->base.sk->family)
1955 case SCTP_PARAM_IPV4_ADDRESS:
1956 af = sctp_get_af_specific(param_type2af(param.p->type));
1957 af->from_addr_param(&addr, param.addr, asoc->peer.port, 0);
1958 scope = sctp_scope(peer_addr);
1959 if (sctp_in_scope(&addr, scope))
1960 if (!sctp_assoc_add_peer(asoc, &addr, gfp))
1964 case SCTP_PARAM_COOKIE_PRESERVATIVE:
1965 if (!sctp_cookie_preserve_enable)
1968 stale = ntohl(param.life->lifespan_increment);
1970 /* Suggested Cookie Life span increment's unit is msec,
1973 asoc->cookie_life.tv_sec += stale / 1000;
1974 asoc->cookie_life.tv_usec += (stale % 1000) * 1000;
1977 case SCTP_PARAM_HOST_NAME_ADDRESS:
1978 SCTP_DEBUG_PRINTK("unimplemented SCTP_HOST_NAME_ADDRESS\n");
1981 case SCTP_PARAM_SUPPORTED_ADDRESS_TYPES:
1982 /* Turn off the default values first so we'll know which
1983 * ones are really set by the peer.
1985 asoc->peer.ipv4_address = 0;
1986 asoc->peer.ipv6_address = 0;
1988 /* Cycle through address types; avoid divide by 0. */
1989 sat = ntohs(param.p->length) - sizeof(sctp_paramhdr_t);
1991 sat /= sizeof(__u16);
1993 for (i = 0; i < sat; ++i) {
1994 switch (param.sat->types[i]) {
1995 case SCTP_PARAM_IPV4_ADDRESS:
1996 asoc->peer.ipv4_address = 1;
1999 case SCTP_PARAM_IPV6_ADDRESS:
2000 asoc->peer.ipv6_address = 1;
2003 case SCTP_PARAM_HOST_NAME_ADDRESS:
2004 asoc->peer.hostname_address = 1;
2007 default: /* Just ignore anything else. */
2013 case SCTP_PARAM_STATE_COOKIE:
2014 asoc->peer.cookie_len =
2015 ntohs(param.p->length) - sizeof(sctp_paramhdr_t);
2016 asoc->peer.cookie = param.cookie->body;
2019 case SCTP_PARAM_HEARTBEAT_INFO:
2020 /* Would be odd to receive, but it causes no problems. */
2023 case SCTP_PARAM_UNRECOGNIZED_PARAMETERS:
2024 /* Rejected during verify stage. */
2027 case SCTP_PARAM_ECN_CAPABLE:
2028 asoc->peer.ecn_capable = 1;
2031 case SCTP_PARAM_ADAPTION_LAYER_IND:
2032 asoc->peer.adaption_ind = param.aind->adaption_ind;
2035 case SCTP_PARAM_FWD_TSN_SUPPORT:
2036 if (sctp_prsctp_enable) {
2037 asoc->peer.prsctp_capable = 1;
2042 /* Any unrecognized parameters should have been caught
2043 * and handled by sctp_verify_param() which should be
2044 * called prior to this routine. Simply log the error
2047 SCTP_DEBUG_PRINTK("Ignoring param: %d for association %p.\n",
2048 ntohs(param.p->type), asoc);
2055 /* Select a new verification tag. */
2056 __u32 sctp_generate_tag(const struct sctp_endpoint *ep)
2058 /* I believe that this random number generator complies with RFC1750.
2059 * A tag of 0 is reserved for special cases (e.g. INIT).
2064 get_random_bytes(&x, sizeof(__u32));
2070 /* Select an initial TSN to send during startup. */
2071 __u32 sctp_generate_tsn(const struct sctp_endpoint *ep)
2075 get_random_bytes(&retval, sizeof(__u32));
2080 * ADDIP 3.1.1 Address Configuration Change Chunk (ASCONF)
2082 * 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
2083 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2084 * | Type = 0xC1 | Chunk Flags | Chunk Length |
2085 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2087 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2088 * | Address Parameter |
2089 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2090 * | ASCONF Parameter #1 |
2091 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2095 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2096 * | ASCONF Parameter #N |
2097 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2099 * Address Parameter and other parameter will not be wrapped in this function
2101 static struct sctp_chunk *sctp_make_asconf(struct sctp_association *asoc,
2102 union sctp_addr *addr,
2105 sctp_addiphdr_t asconf;
2106 struct sctp_chunk *retval;
2107 int length = sizeof(asconf) + vparam_len;
2108 union sctp_addr_param addrparam;
2110 struct sctp_af *af = sctp_get_af_specific(addr->v4.sin_family);
2112 addrlen = af->to_addr_param(addr, &addrparam);
2117 /* Create the chunk. */
2118 retval = sctp_make_chunk(asoc, SCTP_CID_ASCONF, 0, length);
2122 asconf.serial = htonl(asoc->addip_serial++);
2124 retval->subh.addip_hdr =
2125 sctp_addto_chunk(retval, sizeof(asconf), &asconf);
2126 retval->param_hdr.v =
2127 sctp_addto_chunk(retval, addrlen, &addrparam);
2133 * 3.2.1 Add IP Address
2135 * 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
2136 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2137 * | Type = 0xC001 | Length = Variable |
2138 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2139 * | ASCONF-Request Correlation ID |
2140 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2141 * | Address Parameter |
2142 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2144 * 3.2.2 Delete IP Address
2146 * 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
2147 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2148 * | Type = 0xC002 | Length = Variable |
2149 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2150 * | ASCONF-Request Correlation ID |
2151 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2152 * | Address Parameter |
2153 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2156 struct sctp_chunk *sctp_make_asconf_update_ip(struct sctp_association *asoc,
2157 union sctp_addr *laddr,
2158 struct sockaddr *addrs,
2162 sctp_addip_param_t param;
2163 struct sctp_chunk *retval;
2164 union sctp_addr_param addr_param;
2165 union sctp_addr *addr;
2168 int paramlen = sizeof(param);
2169 int addr_param_len = 0;
2173 /* Get total length of all the address parameters. */
2175 for (i = 0; i < addrcnt; i++) {
2176 addr = (union sctp_addr *)addr_buf;
2177 af = sctp_get_af_specific(addr->v4.sin_family);
2178 addr_param_len = af->to_addr_param(addr, &addr_param);
2180 totallen += paramlen;
2181 totallen += addr_param_len;
2183 addr_buf += af->sockaddr_len;
2186 /* Create an asconf chunk with the required length. */
2187 retval = sctp_make_asconf(asoc, laddr, totallen);
2191 /* Add the address parameters to the asconf chunk. */
2193 for (i = 0; i < addrcnt; i++) {
2194 addr = (union sctp_addr *)addr_buf;
2195 af = sctp_get_af_specific(addr->v4.sin_family);
2196 addr_param_len = af->to_addr_param(addr, &addr_param);
2197 param.param_hdr.type = flags;
2198 param.param_hdr.length = htons(paramlen + addr_param_len);
2201 sctp_addto_chunk(retval, paramlen, ¶m);
2202 sctp_addto_chunk(retval, addr_param_len, &addr_param);
2204 addr_buf += af->sockaddr_len;
2210 * 3.2.4 Set Primary IP Address
2212 * 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
2213 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2214 * | Type =0xC004 | Length = Variable |
2215 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2216 * | ASCONF-Request Correlation ID |
2217 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2218 * | Address Parameter |
2219 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2221 * Create an ASCONF chunk with Set Primary IP address parameter.
2223 struct sctp_chunk *sctp_make_asconf_set_prim(struct sctp_association *asoc,
2224 union sctp_addr *addr)
2226 sctp_addip_param_t param;
2227 struct sctp_chunk *retval;
2228 int len = sizeof(param);
2229 union sctp_addr_param addrparam;
2231 struct sctp_af *af = sctp_get_af_specific(addr->v4.sin_family);
2233 addrlen = af->to_addr_param(addr, &addrparam);
2238 /* Create the chunk and make asconf header. */
2239 retval = sctp_make_asconf(asoc, addr, len);
2243 param.param_hdr.type = SCTP_PARAM_SET_PRIMARY;
2244 param.param_hdr.length = htons(len);
2247 sctp_addto_chunk(retval, sizeof(param), ¶m);
2248 sctp_addto_chunk(retval, addrlen, &addrparam);
2253 /* ADDIP 3.1.2 Address Configuration Acknowledgement Chunk (ASCONF-ACK)
2255 * 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
2256 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2257 * | Type = 0x80 | Chunk Flags | Chunk Length |
2258 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2260 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2261 * | ASCONF Parameter Response#1 |
2262 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2266 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2267 * | ASCONF Parameter Response#N |
2268 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2270 * Create an ASCONF_ACK chunk with enough space for the parameter responses.
2272 static struct sctp_chunk *sctp_make_asconf_ack(const struct sctp_association *asoc,
2273 __u32 serial, int vparam_len)
2275 sctp_addiphdr_t asconf;
2276 struct sctp_chunk *retval;
2277 int length = sizeof(asconf) + vparam_len;
2279 /* Create the chunk. */
2280 retval = sctp_make_chunk(asoc, SCTP_CID_ASCONF_ACK, 0, length);
2284 asconf.serial = htonl(serial);
2286 retval->subh.addip_hdr =
2287 sctp_addto_chunk(retval, sizeof(asconf), &asconf);
2292 /* Add response parameters to an ASCONF_ACK chunk. */
2293 static void sctp_add_asconf_response(struct sctp_chunk *chunk, __u32 crr_id,
2294 __u16 err_code, sctp_addip_param_t *asconf_param)
2296 sctp_addip_param_t ack_param;
2297 sctp_errhdr_t err_param;
2298 int asconf_param_len = 0;
2299 int err_param_len = 0;
2300 __u16 response_type;
2302 if (SCTP_ERROR_NO_ERROR == err_code) {
2303 response_type = SCTP_PARAM_SUCCESS_REPORT;
2305 response_type = SCTP_PARAM_ERR_CAUSE;
2306 err_param_len = sizeof(err_param);
2309 ntohs(asconf_param->param_hdr.length);
2312 /* Add Success Indication or Error Cause Indication parameter. */
2313 ack_param.param_hdr.type = response_type;
2314 ack_param.param_hdr.length = htons(sizeof(ack_param) +
2317 ack_param.crr_id = crr_id;
2318 sctp_addto_chunk(chunk, sizeof(ack_param), &ack_param);
2320 if (SCTP_ERROR_NO_ERROR == err_code)
2323 /* Add Error Cause parameter. */
2324 err_param.cause = err_code;
2325 err_param.length = htons(err_param_len + asconf_param_len);
2326 sctp_addto_chunk(chunk, err_param_len, &err_param);
2328 /* Add the failed TLV copied from ASCONF chunk. */
2330 sctp_addto_chunk(chunk, asconf_param_len, asconf_param);
2333 /* Process a asconf parameter. */
2334 static __u16 sctp_process_asconf_param(struct sctp_association *asoc,
2335 struct sctp_chunk *asconf,
2336 sctp_addip_param_t *asconf_param)
2338 struct sctp_transport *peer;
2340 union sctp_addr addr;
2341 struct list_head *pos;
2342 union sctp_addr_param *addr_param;
2344 addr_param = (union sctp_addr_param *)
2345 ((void *)asconf_param + sizeof(sctp_addip_param_t));
2347 af = sctp_get_af_specific(param_type2af(addr_param->v4.param_hdr.type));
2349 return SCTP_ERROR_INV_PARAM;
2351 af->from_addr_param(&addr, addr_param, asoc->peer.port, 0);
2352 switch (asconf_param->param_hdr.type) {
2353 case SCTP_PARAM_ADD_IP:
2354 /* ADDIP 4.3 D9) If an endpoint receives an ADD IP address
2355 * request and does not have the local resources to add this
2356 * new address to the association, it MUST return an Error
2357 * Cause TLV set to the new error code 'Operation Refused
2358 * Due to Resource Shortage'.
2361 peer = sctp_assoc_add_peer(asoc, &addr, GFP_ATOMIC);
2363 return SCTP_ERROR_RSRC_LOW;
2365 /* Start the heartbeat timer. */
2366 if (!mod_timer(&peer->hb_timer, sctp_transport_timeout(peer)))
2367 sctp_transport_hold(peer);
2369 case SCTP_PARAM_DEL_IP:
2370 /* ADDIP 4.3 D7) If a request is received to delete the
2371 * last remaining IP address of a peer endpoint, the receiver
2372 * MUST send an Error Cause TLV with the error cause set to the
2373 * new error code 'Request to Delete Last Remaining IP Address'.
2375 pos = asoc->peer.transport_addr_list.next;
2376 if (pos->next == &asoc->peer.transport_addr_list)
2377 return SCTP_ERROR_DEL_LAST_IP;
2379 /* ADDIP 4.3 D8) If a request is received to delete an IP
2380 * address which is also the source address of the IP packet
2381 * which contained the ASCONF chunk, the receiver MUST reject
2382 * this request. To reject the request the receiver MUST send
2383 * an Error Cause TLV set to the new error code 'Request to
2384 * Delete Source IP Address'
2386 if (sctp_cmp_addr_exact(sctp_source(asconf), &addr))
2387 return SCTP_ERROR_DEL_SRC_IP;
2389 sctp_assoc_del_peer(asoc, &addr);
2391 case SCTP_PARAM_SET_PRIMARY:
2392 peer = sctp_assoc_lookup_paddr(asoc, &addr);
2394 return SCTP_ERROR_INV_PARAM;
2396 sctp_assoc_set_primary(asoc, peer);
2399 return SCTP_ERROR_INV_PARAM;
2403 return SCTP_ERROR_NO_ERROR;
2406 /* Process an incoming ASCONF chunk with the next expected serial no. and
2407 * return an ASCONF_ACK chunk to be sent in response.
2409 struct sctp_chunk *sctp_process_asconf(struct sctp_association *asoc,
2410 struct sctp_chunk *asconf)
2412 sctp_addiphdr_t *hdr;
2413 union sctp_addr_param *addr_param;
2414 sctp_addip_param_t *asconf_param;
2415 struct sctp_chunk *asconf_ack;
2419 int chunk_len = asconf->skb->len;
2421 int all_param_pass = 1;
2423 hdr = (sctp_addiphdr_t *)asconf->skb->data;
2424 serial = ntohl(hdr->serial);
2426 /* Skip the addiphdr and store a pointer to address parameter. */
2427 length = sizeof(sctp_addiphdr_t);
2428 addr_param = (union sctp_addr_param *)(asconf->skb->data + length);
2429 chunk_len -= length;
2431 /* Skip the address parameter and store a pointer to the first
2434 length = ntohs(addr_param->v4.param_hdr.length);
2435 asconf_param = (sctp_addip_param_t *)((void *)addr_param + length);
2436 chunk_len -= length;
2438 /* create an ASCONF_ACK chunk.
2439 * Based on the definitions of parameters, we know that the size of
2440 * ASCONF_ACK parameters are less than or equal to the twice of ASCONF
2443 asconf_ack = sctp_make_asconf_ack(asoc, serial, chunk_len * 2);
2447 /* Process the TLVs contained within the ASCONF chunk. */
2448 while (chunk_len > 0) {
2449 err_code = sctp_process_asconf_param(asoc, asconf,
2452 * If an error response is received for a TLV parameter,
2453 * all TLVs with no response before the failed TLV are
2454 * considered successful if not reported. All TLVs after
2455 * the failed response are considered unsuccessful unless
2456 * a specific success indication is present for the parameter.
2458 if (SCTP_ERROR_NO_ERROR != err_code)
2461 if (!all_param_pass)
2462 sctp_add_asconf_response(asconf_ack,
2463 asconf_param->crr_id, err_code,
2466 /* ADDIP 4.3 D11) When an endpoint receiving an ASCONF to add
2467 * an IP address sends an 'Out of Resource' in its response, it
2468 * MUST also fail any subsequent add or delete requests bundled
2471 if (SCTP_ERROR_RSRC_LOW == err_code)
2474 /* Move to the next ASCONF param. */
2475 length = ntohs(asconf_param->param_hdr.length);
2476 asconf_param = (sctp_addip_param_t *)((void *)asconf_param +
2478 chunk_len -= length;
2482 asoc->peer.addip_serial++;
2484 /* If we are sending a new ASCONF_ACK hold a reference to it in assoc
2485 * after freeing the reference to old asconf ack if any.
2488 if (asoc->addip_last_asconf_ack)
2489 sctp_chunk_free(asoc->addip_last_asconf_ack);
2491 sctp_chunk_hold(asconf_ack);
2492 asoc->addip_last_asconf_ack = asconf_ack;
2498 /* Process a asconf parameter that is successfully acked. */
2499 static int sctp_asconf_param_success(struct sctp_association *asoc,
2500 sctp_addip_param_t *asconf_param)
2503 union sctp_addr addr;
2504 struct sctp_bind_addr *bp = &asoc->base.bind_addr;
2505 union sctp_addr_param *addr_param;
2506 struct list_head *pos;
2507 struct sctp_transport *transport;
2510 addr_param = (union sctp_addr_param *)
2511 ((void *)asconf_param + sizeof(sctp_addip_param_t));
2513 /* We have checked the packet before, so we do not check again. */
2514 af = sctp_get_af_specific(param_type2af(addr_param->v4.param_hdr.type));
2515 af->from_addr_param(&addr, addr_param, bp->port, 0);
2517 switch (asconf_param->param_hdr.type) {
2518 case SCTP_PARAM_ADD_IP:
2519 sctp_local_bh_disable();
2520 sctp_write_lock(&asoc->base.addr_lock);
2521 retval = sctp_add_bind_addr(bp, &addr, GFP_ATOMIC);
2522 sctp_write_unlock(&asoc->base.addr_lock);
2523 sctp_local_bh_enable();
2525 case SCTP_PARAM_DEL_IP:
2526 sctp_local_bh_disable();
2527 sctp_write_lock(&asoc->base.addr_lock);
2528 retval = sctp_del_bind_addr(bp, &addr);
2529 sctp_write_unlock(&asoc->base.addr_lock);
2530 sctp_local_bh_enable();
2531 list_for_each(pos, &asoc->peer.transport_addr_list) {
2532 transport = list_entry(pos, struct sctp_transport,
2534 sctp_transport_route(transport, NULL,
2535 sctp_sk(asoc->base.sk));
2545 /* Get the corresponding ASCONF response error code from the ASCONF_ACK chunk
2546 * for the given asconf parameter. If there is no response for this parameter,
2547 * return the error code based on the third argument 'no_err'.
2549 * A7) If an error response is received for a TLV parameter, all TLVs with no
2550 * response before the failed TLV are considered successful if not reported.
2551 * All TLVs after the failed response are considered unsuccessful unless a
2552 * specific success indication is present for the parameter.
2554 static __u16 sctp_get_asconf_response(struct sctp_chunk *asconf_ack,
2555 sctp_addip_param_t *asconf_param,
2558 sctp_addip_param_t *asconf_ack_param;
2559 sctp_errhdr_t *err_param;
2561 int asconf_ack_len = asconf_ack->skb->len;
2565 err_code = SCTP_ERROR_NO_ERROR;
2567 err_code = SCTP_ERROR_REQ_REFUSED;
2569 /* Skip the addiphdr from the asconf_ack chunk and store a pointer to
2570 * the first asconf_ack parameter.
2572 length = sizeof(sctp_addiphdr_t);
2573 asconf_ack_param = (sctp_addip_param_t *)(asconf_ack->skb->data +
2575 asconf_ack_len -= length;
2577 while (asconf_ack_len > 0) {
2578 if (asconf_ack_param->crr_id == asconf_param->crr_id) {
2579 switch(asconf_ack_param->param_hdr.type) {
2580 case SCTP_PARAM_SUCCESS_REPORT:
2581 return SCTP_ERROR_NO_ERROR;
2582 case SCTP_PARAM_ERR_CAUSE:
2583 length = sizeof(sctp_addip_param_t);
2584 err_param = (sctp_errhdr_t *)
2585 ((void *)asconf_ack_param + length);
2586 asconf_ack_len -= length;
2587 if (asconf_ack_len > 0)
2588 return err_param->cause;
2590 return SCTP_ERROR_INV_PARAM;
2593 return SCTP_ERROR_INV_PARAM;
2597 length = ntohs(asconf_ack_param->param_hdr.length);
2598 asconf_ack_param = (sctp_addip_param_t *)
2599 ((void *)asconf_ack_param + length);
2600 asconf_ack_len -= length;
2606 /* Process an incoming ASCONF_ACK chunk against the cached last ASCONF chunk. */
2607 int sctp_process_asconf_ack(struct sctp_association *asoc,
2608 struct sctp_chunk *asconf_ack)
2610 struct sctp_chunk *asconf = asoc->addip_last_asconf;
2611 union sctp_addr_param *addr_param;
2612 sctp_addip_param_t *asconf_param;
2614 int asconf_len = asconf->skb->len;
2615 int all_param_pass = 0;
2618 __u16 err_code = SCTP_ERROR_NO_ERROR;
2620 /* Skip the chunkhdr and addiphdr from the last asconf sent and store
2621 * a pointer to address parameter.
2623 length = sizeof(sctp_addip_chunk_t);
2624 addr_param = (union sctp_addr_param *)(asconf->skb->data + length);
2625 asconf_len -= length;
2627 /* Skip the address parameter in the last asconf sent and store a
2628 * pointer to the first asconf paramter.
2630 length = ntohs(addr_param->v4.param_hdr.length);
2631 asconf_param = (sctp_addip_param_t *)((void *)addr_param + length);
2632 asconf_len -= length;
2635 * A8) If there is no response(s) to specific TLV parameter(s), and no
2636 * failures are indicated, then all request(s) are considered
2639 if (asconf_ack->skb->len == sizeof(sctp_addiphdr_t))
2642 /* Process the TLVs contained in the last sent ASCONF chunk. */
2643 while (asconf_len > 0) {
2645 err_code = SCTP_ERROR_NO_ERROR;
2647 err_code = sctp_get_asconf_response(asconf_ack,
2650 if (no_err && (SCTP_ERROR_NO_ERROR != err_code))
2655 case SCTP_ERROR_NO_ERROR:
2656 retval = sctp_asconf_param_success(asoc, asconf_param);
2659 case SCTP_ERROR_RSRC_LOW:
2663 case SCTP_ERROR_INV_PARAM:
2664 /* Disable sending this type of asconf parameter in
2667 asoc->peer.addip_disabled_mask |=
2668 asconf_param->param_hdr.type;
2671 case SCTP_ERROR_REQ_REFUSED:
2672 case SCTP_ERROR_DEL_LAST_IP:
2673 case SCTP_ERROR_DEL_SRC_IP:
2678 /* Skip the processed asconf parameter and move to the next
2681 length = ntohs(asconf_param->param_hdr.length);
2682 asconf_param = (sctp_addip_param_t *)((void *)asconf_param +
2684 asconf_len -= length;
2687 /* Free the cached last sent asconf chunk. */
2688 sctp_chunk_free(asconf);
2689 asoc->addip_last_asconf = NULL;
2691 /* Send the next asconf chunk from the addip chunk queue. */
2692 asconf = (struct sctp_chunk *)__skb_dequeue(&asoc->addip_chunks);
2694 /* Hold the chunk until an ASCONF_ACK is received. */
2695 sctp_chunk_hold(asconf);
2696 if (sctp_primitive_ASCONF(asoc, asconf))
2697 sctp_chunk_free(asconf);
2699 asoc->addip_last_asconf = asconf;
2705 /* Make a FWD TSN chunk. */
2706 struct sctp_chunk *sctp_make_fwdtsn(const struct sctp_association *asoc,
2707 __u32 new_cum_tsn, size_t nstreams,
2708 struct sctp_fwdtsn_skip *skiplist)
2710 struct sctp_chunk *retval = NULL;
2711 struct sctp_fwdtsn_chunk *ftsn_chunk;
2712 struct sctp_fwdtsn_hdr ftsn_hdr;
2713 struct sctp_fwdtsn_skip skip;
2717 hint = (nstreams + 1) * sizeof(__u32);
2719 /* Maybe set the T-bit if we have no association. */
2720 retval = sctp_make_chunk(asoc, SCTP_CID_FWD_TSN, 0, hint);
2725 ftsn_chunk = (struct sctp_fwdtsn_chunk *)retval->subh.fwdtsn_hdr;
2727 ftsn_hdr.new_cum_tsn = htonl(new_cum_tsn);
2728 retval->subh.fwdtsn_hdr =
2729 sctp_addto_chunk(retval, sizeof(ftsn_hdr), &ftsn_hdr);
2731 for (i = 0; i < nstreams; i++) {
2732 skip.stream = skiplist[i].stream;
2733 skip.ssn = skiplist[i].ssn;
2734 sctp_addto_chunk(retval, sizeof(skip), &skip);