1 /* SCTP kernel implementation
2 * (C) Copyright IBM Corp. 2001, 2004
3 * Copyright (c) 1999-2000 Cisco, Inc.
4 * Copyright (c) 1999-2001 Motorola, Inc.
5 * Copyright (c) 2001-2002 Intel Corp.
7 * This file is part of the SCTP kernel implementation
9 * These functions work with the state functions in sctp_sm_statefuns.c
10 * to implement the state operations. These functions implement the
11 * steps which require modifying existing data structures.
13 * This SCTP implementation is free software;
14 * you can redistribute it and/or modify it under the terms of
15 * the GNU General Public License as published by
16 * the Free Software Foundation; either version 2, or (at your option)
19 * This SCTP implementation is distributed in the hope that it
20 * will be useful, but WITHOUT ANY WARRANTY; without even the implied
21 * ************************
22 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
23 * See the GNU General Public License for more details.
25 * You should have received a copy of the GNU General Public License
26 * along with GNU CC; see the file COPYING. If not, see
27 * <http://www.gnu.org/licenses/>.
29 * Please send any bug reports or fixes you make to the
31 * lksctp developers <linux-sctp@vger.kernel.org>
33 * Written or modified by:
34 * La Monte H.P. Yarroll <piggy@acm.org>
35 * Karl Knutson <karl@athena.chicago.il.us>
36 * C. Robin <chris@hundredacre.ac.uk>
37 * Jon Grimm <jgrimm@us.ibm.com>
38 * Xingang Guo <xingang.guo@intel.com>
39 * Dajiang Zhang <dajiang.zhang@nokia.com>
40 * Sridhar Samudrala <sri@us.ibm.com>
41 * Daisy Chang <daisyc@us.ibm.com>
42 * Ardelle Fan <ardelle.fan@intel.com>
43 * Kevin Gao <kevin.gao@intel.com>
46 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
48 #include <crypto/hash.h>
49 #include <linux/types.h>
50 #include <linux/kernel.h>
52 #include <linux/ipv6.h>
53 #include <linux/net.h>
54 #include <linux/inet.h>
55 #include <linux/scatterlist.h>
56 #include <linux/slab.h>
59 #include <linux/skbuff.h>
60 #include <linux/random.h> /* for get_random_bytes */
61 #include <net/sctp/sctp.h>
62 #include <net/sctp/sm.h>
64 static struct sctp_chunk *sctp_make_control(const struct sctp_association *asoc,
65 __u8 type, __u8 flags, int paylen,
67 static struct sctp_chunk *sctp_make_data(const struct sctp_association *asoc,
68 __u8 flags, int paylen, gfp_t gfp);
69 static struct sctp_chunk *_sctp_make_chunk(const struct sctp_association *asoc,
70 __u8 type, __u8 flags, int paylen,
72 static sctp_cookie_param_t *sctp_pack_cookie(const struct sctp_endpoint *ep,
73 const struct sctp_association *asoc,
74 const struct sctp_chunk *init_chunk,
76 const __u8 *raw_addrs, int addrs_len);
77 static int sctp_process_param(struct sctp_association *asoc,
78 union sctp_params param,
79 const union sctp_addr *peer_addr,
81 static void *sctp_addto_param(struct sctp_chunk *chunk, int len,
83 static void *sctp_addto_chunk_fixed(struct sctp_chunk *, int len,
86 /* Control chunk destructor */
87 static void sctp_control_release_owner(struct sk_buff *skb)
89 /*TODO: do memory release */
92 static void sctp_control_set_owner_w(struct sctp_chunk *chunk)
94 struct sctp_association *asoc = chunk->asoc;
95 struct sk_buff *skb = chunk->skb;
97 /* TODO: properly account for control chunks.
98 * To do it right we'll need:
99 * 1) endpoint if association isn't known.
100 * 2) proper memory accounting.
102 * For now don't do anything for now.
104 skb->sk = asoc ? asoc->base.sk : NULL;
105 skb->destructor = sctp_control_release_owner;
108 /* What was the inbound interface for this chunk? */
109 int sctp_chunk_iif(const struct sctp_chunk *chunk)
111 struct sk_buff *skb = chunk->skb;
113 return SCTP_INPUT_CB(skb)->af->skb_iif(skb);
116 /* RFC 2960 3.3.2 Initiation (INIT) (1)
118 * Note 2: The ECN capable field is reserved for future use of
119 * Explicit Congestion Notification.
121 static const struct sctp_paramhdr ecap_param = {
122 SCTP_PARAM_ECN_CAPABLE,
123 cpu_to_be16(sizeof(struct sctp_paramhdr)),
125 static const struct sctp_paramhdr prsctp_param = {
126 SCTP_PARAM_FWD_TSN_SUPPORT,
127 cpu_to_be16(sizeof(struct sctp_paramhdr)),
130 /* A helper to initialize an op error inside a
131 * provided chunk, as most cause codes will be embedded inside an
134 void sctp_init_cause(struct sctp_chunk *chunk, __be16 cause_code,
140 /* Cause code constants are now defined in network order. */
141 err.cause = cause_code;
142 len = sizeof(sctp_errhdr_t) + paylen;
143 err.length = htons(len);
144 chunk->subh.err_hdr = sctp_addto_chunk(chunk, sizeof(sctp_errhdr_t), &err);
147 /* A helper to initialize an op error inside a
148 * provided chunk, as most cause codes will be embedded inside an
149 * abort chunk. Differs from sctp_init_cause in that it won't oops
150 * if there isn't enough space in the op error chunk
152 static int sctp_init_cause_fixed(struct sctp_chunk *chunk, __be16 cause_code,
158 /* Cause code constants are now defined in network order. */
159 err.cause = cause_code;
160 len = sizeof(sctp_errhdr_t) + paylen;
161 err.length = htons(len);
163 if (skb_tailroom(chunk->skb) < len)
165 chunk->subh.err_hdr = sctp_addto_chunk_fixed(chunk,
166 sizeof(sctp_errhdr_t),
170 /* 3.3.2 Initiation (INIT) (1)
172 * This chunk is used to initiate a SCTP association between two
173 * endpoints. The format of the INIT chunk is shown below:
176 * 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
177 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
178 * | Type = 1 | Chunk Flags | Chunk Length |
179 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
181 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
182 * | Advertised Receiver Window Credit (a_rwnd) |
183 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
184 * | Number of Outbound Streams | Number of Inbound Streams |
185 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
187 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
189 * / Optional/Variable-Length Parameters /
191 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
194 * The INIT chunk contains the following parameters. Unless otherwise
195 * noted, each parameter MUST only be included once in the INIT chunk.
197 * Fixed Parameters Status
198 * ----------------------------------------------
199 * Initiate Tag Mandatory
200 * Advertised Receiver Window Credit Mandatory
201 * Number of Outbound Streams Mandatory
202 * Number of Inbound Streams Mandatory
203 * Initial TSN Mandatory
205 * Variable Parameters Status Type Value
206 * -------------------------------------------------------------
207 * IPv4 Address (Note 1) Optional 5
208 * IPv6 Address (Note 1) Optional 6
209 * Cookie Preservative Optional 9
210 * Reserved for ECN Capable (Note 2) Optional 32768 (0x8000)
211 * Host Name Address (Note 3) Optional 11
212 * Supported Address Types (Note 4) Optional 12
214 struct sctp_chunk *sctp_make_init(const struct sctp_association *asoc,
215 const struct sctp_bind_addr *bp,
216 gfp_t gfp, int vparam_len)
218 struct net *net = sock_net(asoc->base.sk);
219 struct sctp_endpoint *ep = asoc->ep;
221 union sctp_params addrs;
223 struct sctp_chunk *retval = NULL;
224 int num_types, addrs_len = 0;
225 struct sctp_sock *sp;
226 sctp_supported_addrs_param_t sat;
228 sctp_adaptation_ind_param_t aiparam;
229 sctp_supported_ext_param_t ext_param;
232 sctp_paramhdr_t *auth_chunks = NULL,
235 /* RFC 2960 3.3.2 Initiation (INIT) (1)
237 * Note 1: The INIT chunks can contain multiple addresses that
238 * can be IPv4 and/or IPv6 in any combination.
242 /* Convert the provided bind address list to raw format. */
243 addrs = sctp_bind_addrs_to_raw(bp, &addrs_len, gfp);
245 init.init_tag = htonl(asoc->c.my_vtag);
246 init.a_rwnd = htonl(asoc->rwnd);
247 init.num_outbound_streams = htons(asoc->c.sinit_num_ostreams);
248 init.num_inbound_streams = htons(asoc->c.sinit_max_instreams);
249 init.initial_tsn = htonl(asoc->c.initial_tsn);
251 /* How many address types are needed? */
252 sp = sctp_sk(asoc->base.sk);
253 num_types = sp->pf->supported_addrs(sp, types);
255 chunksize = sizeof(init) + addrs_len;
256 chunksize += WORD_ROUND(SCTP_SAT_LEN(num_types));
257 chunksize += sizeof(ecap_param);
259 if (asoc->prsctp_enable)
260 chunksize += sizeof(prsctp_param);
262 /* ADDIP: Section 4.2.7:
263 * An implementation supporting this extension [ADDIP] MUST list
264 * the ASCONF,the ASCONF-ACK, and the AUTH chunks in its INIT and
265 * INIT-ACK parameters.
267 if (net->sctp.addip_enable) {
268 extensions[num_ext] = SCTP_CID_ASCONF;
269 extensions[num_ext+1] = SCTP_CID_ASCONF_ACK;
273 if (sp->adaptation_ind)
274 chunksize += sizeof(aiparam);
276 chunksize += vparam_len;
278 /* Account for AUTH related parameters */
279 if (ep->auth_enable) {
280 /* Add random parameter length*/
281 chunksize += sizeof(asoc->c.auth_random);
283 /* Add HMACS parameter length if any were defined */
284 auth_hmacs = (sctp_paramhdr_t *)asoc->c.auth_hmacs;
285 if (auth_hmacs->length)
286 chunksize += WORD_ROUND(ntohs(auth_hmacs->length));
290 /* Add CHUNKS parameter length */
291 auth_chunks = (sctp_paramhdr_t *)asoc->c.auth_chunks;
292 if (auth_chunks->length)
293 chunksize += WORD_ROUND(ntohs(auth_chunks->length));
297 extensions[num_ext] = SCTP_CID_AUTH;
301 /* If we have any extensions to report, account for that */
303 chunksize += WORD_ROUND(sizeof(sctp_supported_ext_param_t) +
306 /* RFC 2960 3.3.2 Initiation (INIT) (1)
308 * Note 3: An INIT chunk MUST NOT contain more than one Host
309 * Name address parameter. Moreover, the sender of the INIT
310 * MUST NOT combine any other address types with the Host Name
311 * address in the INIT. The receiver of INIT MUST ignore any
312 * other address types if the Host Name address parameter is
313 * present in the received INIT chunk.
315 * PLEASE DO NOT FIXME [This version does not support Host Name.]
318 retval = sctp_make_control(asoc, SCTP_CID_INIT, 0, chunksize, gfp);
322 retval->subh.init_hdr =
323 sctp_addto_chunk(retval, sizeof(init), &init);
324 retval->param_hdr.v =
325 sctp_addto_chunk(retval, addrs_len, addrs.v);
327 /* RFC 2960 3.3.2 Initiation (INIT) (1)
329 * Note 4: This parameter, when present, specifies all the
330 * address types the sending endpoint can support. The absence
331 * of this parameter indicates that the sending endpoint can
332 * support any address type.
334 sat.param_hdr.type = SCTP_PARAM_SUPPORTED_ADDRESS_TYPES;
335 sat.param_hdr.length = htons(SCTP_SAT_LEN(num_types));
336 sctp_addto_chunk(retval, sizeof(sat), &sat);
337 sctp_addto_chunk(retval, num_types * sizeof(__u16), &types);
339 sctp_addto_chunk(retval, sizeof(ecap_param), &ecap_param);
341 /* Add the supported extensions parameter. Be nice and add this
342 * fist before addiding the parameters for the extensions themselves
345 ext_param.param_hdr.type = SCTP_PARAM_SUPPORTED_EXT;
346 ext_param.param_hdr.length =
347 htons(sizeof(sctp_supported_ext_param_t) + num_ext);
348 sctp_addto_chunk(retval, sizeof(sctp_supported_ext_param_t),
350 sctp_addto_param(retval, num_ext, extensions);
353 if (asoc->prsctp_enable)
354 sctp_addto_chunk(retval, sizeof(prsctp_param), &prsctp_param);
356 if (sp->adaptation_ind) {
357 aiparam.param_hdr.type = SCTP_PARAM_ADAPTATION_LAYER_IND;
358 aiparam.param_hdr.length = htons(sizeof(aiparam));
359 aiparam.adaptation_ind = htonl(sp->adaptation_ind);
360 sctp_addto_chunk(retval, sizeof(aiparam), &aiparam);
363 /* Add SCTP-AUTH chunks to the parameter list */
364 if (ep->auth_enable) {
365 sctp_addto_chunk(retval, sizeof(asoc->c.auth_random),
366 asoc->c.auth_random);
368 sctp_addto_chunk(retval, ntohs(auth_hmacs->length),
371 sctp_addto_chunk(retval, ntohs(auth_chunks->length),
379 struct sctp_chunk *sctp_make_init_ack(const struct sctp_association *asoc,
380 const struct sctp_chunk *chunk,
381 gfp_t gfp, int unkparam_len)
383 sctp_inithdr_t initack;
384 struct sctp_chunk *retval;
385 union sctp_params addrs;
386 struct sctp_sock *sp;
388 sctp_cookie_param_t *cookie;
391 sctp_adaptation_ind_param_t aiparam;
392 sctp_supported_ext_param_t ext_param;
395 sctp_paramhdr_t *auth_chunks = NULL,
401 /* Note: there may be no addresses to embed. */
402 addrs = sctp_bind_addrs_to_raw(&asoc->base.bind_addr, &addrs_len, gfp);
404 initack.init_tag = htonl(asoc->c.my_vtag);
405 initack.a_rwnd = htonl(asoc->rwnd);
406 initack.num_outbound_streams = htons(asoc->c.sinit_num_ostreams);
407 initack.num_inbound_streams = htons(asoc->c.sinit_max_instreams);
408 initack.initial_tsn = htonl(asoc->c.initial_tsn);
410 /* FIXME: We really ought to build the cookie right
411 * into the packet instead of allocating more fresh memory.
413 cookie = sctp_pack_cookie(asoc->ep, asoc, chunk, &cookie_len,
418 /* Calculate the total size of allocation, include the reserved
419 * space for reporting unknown parameters if it is specified.
421 sp = sctp_sk(asoc->base.sk);
422 chunksize = sizeof(initack) + addrs_len + cookie_len + unkparam_len;
424 /* Tell peer that we'll do ECN only if peer advertised such cap. */
425 if (asoc->peer.ecn_capable)
426 chunksize += sizeof(ecap_param);
428 if (asoc->peer.prsctp_capable)
429 chunksize += sizeof(prsctp_param);
431 if (asoc->peer.asconf_capable) {
432 extensions[num_ext] = SCTP_CID_ASCONF;
433 extensions[num_ext+1] = SCTP_CID_ASCONF_ACK;
437 if (sp->adaptation_ind)
438 chunksize += sizeof(aiparam);
440 if (asoc->peer.auth_capable) {
441 auth_random = (sctp_paramhdr_t *)asoc->c.auth_random;
442 chunksize += ntohs(auth_random->length);
444 auth_hmacs = (sctp_paramhdr_t *)asoc->c.auth_hmacs;
445 if (auth_hmacs->length)
446 chunksize += WORD_ROUND(ntohs(auth_hmacs->length));
450 auth_chunks = (sctp_paramhdr_t *)asoc->c.auth_chunks;
451 if (auth_chunks->length)
452 chunksize += WORD_ROUND(ntohs(auth_chunks->length));
456 extensions[num_ext] = SCTP_CID_AUTH;
461 chunksize += WORD_ROUND(sizeof(sctp_supported_ext_param_t) +
464 /* Now allocate and fill out the chunk. */
465 retval = sctp_make_control(asoc, SCTP_CID_INIT_ACK, 0, chunksize, gfp);
469 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
471 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
472 * HEARTBEAT ACK, * etc.) to the same destination transport
473 * address from which it received the DATA or control chunk
474 * to which it is replying.
476 * [INIT ACK back to where the INIT came from.]
478 retval->transport = chunk->transport;
480 retval->subh.init_hdr =
481 sctp_addto_chunk(retval, sizeof(initack), &initack);
482 retval->param_hdr.v = sctp_addto_chunk(retval, addrs_len, addrs.v);
483 sctp_addto_chunk(retval, cookie_len, cookie);
484 if (asoc->peer.ecn_capable)
485 sctp_addto_chunk(retval, sizeof(ecap_param), &ecap_param);
487 ext_param.param_hdr.type = SCTP_PARAM_SUPPORTED_EXT;
488 ext_param.param_hdr.length =
489 htons(sizeof(sctp_supported_ext_param_t) + num_ext);
490 sctp_addto_chunk(retval, sizeof(sctp_supported_ext_param_t),
492 sctp_addto_param(retval, num_ext, extensions);
494 if (asoc->peer.prsctp_capable)
495 sctp_addto_chunk(retval, sizeof(prsctp_param), &prsctp_param);
497 if (sp->adaptation_ind) {
498 aiparam.param_hdr.type = SCTP_PARAM_ADAPTATION_LAYER_IND;
499 aiparam.param_hdr.length = htons(sizeof(aiparam));
500 aiparam.adaptation_ind = htonl(sp->adaptation_ind);
501 sctp_addto_chunk(retval, sizeof(aiparam), &aiparam);
504 if (asoc->peer.auth_capable) {
505 sctp_addto_chunk(retval, ntohs(auth_random->length),
508 sctp_addto_chunk(retval, ntohs(auth_hmacs->length),
511 sctp_addto_chunk(retval, ntohs(auth_chunks->length),
515 /* We need to remove the const qualifier at this point. */
516 retval->asoc = (struct sctp_association *) asoc;
525 /* 3.3.11 Cookie Echo (COOKIE ECHO) (10):
527 * This chunk is used only during the initialization of an association.
528 * It is sent by the initiator of an association to its peer to complete
529 * the initialization process. This chunk MUST precede any DATA chunk
530 * sent within the association, but MAY be bundled with one or more DATA
531 * chunks in the same packet.
534 * 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
535 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
536 * | Type = 10 |Chunk Flags | Length |
537 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
540 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
544 * Set to zero on transmit and ignored on receipt.
546 * Length: 16 bits (unsigned integer)
548 * Set to the size of the chunk in bytes, including the 4 bytes of
549 * the chunk header and the size of the Cookie.
551 * Cookie: variable size
553 * This field must contain the exact cookie received in the
554 * State Cookie parameter from the previous INIT ACK.
556 * An implementation SHOULD make the cookie as small as possible
557 * to insure interoperability.
559 struct sctp_chunk *sctp_make_cookie_echo(const struct sctp_association *asoc,
560 const struct sctp_chunk *chunk)
562 struct sctp_chunk *retval;
566 cookie = asoc->peer.cookie;
567 cookie_len = asoc->peer.cookie_len;
569 /* Build a cookie echo chunk. */
570 retval = sctp_make_control(asoc, SCTP_CID_COOKIE_ECHO, 0,
571 cookie_len, GFP_ATOMIC);
574 retval->subh.cookie_hdr =
575 sctp_addto_chunk(retval, cookie_len, cookie);
577 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
579 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
580 * HEARTBEAT ACK, * etc.) to the same destination transport
581 * address from which it * received the DATA or control chunk
582 * to which it is replying.
584 * [COOKIE ECHO back to where the INIT ACK came from.]
587 retval->transport = chunk->transport;
593 /* 3.3.12 Cookie Acknowledgement (COOKIE ACK) (11):
595 * This chunk is used only during the initialization of an
596 * association. It is used to acknowledge the receipt of a COOKIE
597 * ECHO chunk. This chunk MUST precede any DATA or SACK chunk sent
598 * within the association, but MAY be bundled with one or more DATA
599 * chunks or SACK chunk in the same SCTP packet.
602 * 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
603 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
604 * | Type = 11 |Chunk Flags | Length = 4 |
605 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
607 * Chunk Flags: 8 bits
609 * Set to zero on transmit and ignored on receipt.
611 struct sctp_chunk *sctp_make_cookie_ack(const struct sctp_association *asoc,
612 const struct sctp_chunk *chunk)
614 struct sctp_chunk *retval;
616 retval = sctp_make_control(asoc, SCTP_CID_COOKIE_ACK, 0, 0, GFP_ATOMIC);
618 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
620 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
621 * HEARTBEAT ACK, * etc.) to the same destination transport
622 * address from which it * received the DATA or control chunk
623 * to which it is replying.
625 * [COOKIE ACK back to where the COOKIE ECHO came from.]
628 retval->transport = chunk->transport;
634 * Appendix A: Explicit Congestion Notification:
637 * RFC 2481 details a specific bit for a sender to send in the header of
638 * its next outbound TCP segment to indicate to its peer that it has
639 * reduced its congestion window. This is termed the CWR bit. For
640 * SCTP the same indication is made by including the CWR chunk.
641 * This chunk contains one data element, i.e. the TSN number that
642 * was sent in the ECNE chunk. This element represents the lowest
643 * TSN number in the datagram that was originally marked with the
647 * 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
648 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
649 * | Chunk Type=13 | Flags=00000000| Chunk Length = 8 |
650 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
651 * | Lowest TSN Number |
652 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
654 * Note: The CWR is considered a Control chunk.
656 struct sctp_chunk *sctp_make_cwr(const struct sctp_association *asoc,
657 const __u32 lowest_tsn,
658 const struct sctp_chunk *chunk)
660 struct sctp_chunk *retval;
663 cwr.lowest_tsn = htonl(lowest_tsn);
664 retval = sctp_make_control(asoc, SCTP_CID_ECN_CWR, 0,
665 sizeof(sctp_cwrhdr_t), GFP_ATOMIC);
670 retval->subh.ecn_cwr_hdr =
671 sctp_addto_chunk(retval, sizeof(cwr), &cwr);
673 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
675 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
676 * HEARTBEAT ACK, * etc.) to the same destination transport
677 * address from which it * received the DATA or control chunk
678 * to which it is replying.
680 * [Report a reduced congestion window back to where the ECNE
684 retval->transport = chunk->transport;
690 /* Make an ECNE chunk. This is a congestion experienced report. */
691 struct sctp_chunk *sctp_make_ecne(const struct sctp_association *asoc,
692 const __u32 lowest_tsn)
694 struct sctp_chunk *retval;
697 ecne.lowest_tsn = htonl(lowest_tsn);
698 retval = sctp_make_control(asoc, SCTP_CID_ECN_ECNE, 0,
699 sizeof(sctp_ecnehdr_t), GFP_ATOMIC);
702 retval->subh.ecne_hdr =
703 sctp_addto_chunk(retval, sizeof(ecne), &ecne);
709 static void sctp_set_prsctp_policy(struct sctp_chunk *chunk,
710 const struct sctp_sndrcvinfo *sinfo)
712 if (!chunk->asoc->prsctp_enable)
715 if (SCTP_PR_TTL_ENABLED(sinfo->sinfo_flags))
716 chunk->prsctp_param =
717 jiffies + msecs_to_jiffies(sinfo->sinfo_timetolive);
718 else if (SCTP_PR_RTX_ENABLED(sinfo->sinfo_flags) ||
719 SCTP_PR_PRIO_ENABLED(sinfo->sinfo_flags))
720 chunk->prsctp_param = sinfo->sinfo_timetolive;
723 /* Make a DATA chunk for the given association from the provided
724 * parameters. However, do not populate the data payload.
726 struct sctp_chunk *sctp_make_datafrag_empty(struct sctp_association *asoc,
727 const struct sctp_sndrcvinfo *sinfo,
728 int data_len, __u8 flags, __u16 ssn,
731 struct sctp_chunk *retval;
732 struct sctp_datahdr dp;
735 /* We assign the TSN as LATE as possible, not here when
736 * creating the chunk.
739 dp.stream = htons(sinfo->sinfo_stream);
740 dp.ppid = sinfo->sinfo_ppid;
742 /* Set the flags for an unordered send. */
743 if (sinfo->sinfo_flags & SCTP_UNORDERED) {
744 flags |= SCTP_DATA_UNORDERED;
749 chunk_len = sizeof(dp) + data_len;
750 retval = sctp_make_data(asoc, flags, chunk_len, gfp);
754 retval->subh.data_hdr = sctp_addto_chunk(retval, sizeof(dp), &dp);
755 memcpy(&retval->sinfo, sinfo, sizeof(struct sctp_sndrcvinfo));
756 sctp_set_prsctp_policy(retval, sinfo);
762 /* Create a selective ackowledgement (SACK) for the given
763 * association. This reports on which TSN's we've seen to date,
764 * including duplicates and gaps.
766 struct sctp_chunk *sctp_make_sack(const struct sctp_association *asoc)
768 struct sctp_chunk *retval;
769 struct sctp_sackhdr sack;
772 __u16 num_gabs, num_dup_tsns;
773 struct sctp_association *aptr = (struct sctp_association *)asoc;
774 struct sctp_tsnmap *map = (struct sctp_tsnmap *)&asoc->peer.tsn_map;
775 struct sctp_gap_ack_block gabs[SCTP_MAX_GABS];
776 struct sctp_transport *trans;
778 memset(gabs, 0, sizeof(gabs));
779 ctsn = sctp_tsnmap_get_ctsn(map);
781 pr_debug("%s: sackCTSNAck sent:0x%x\n", __func__, ctsn);
783 /* How much room is needed in the chunk? */
784 num_gabs = sctp_tsnmap_num_gabs(map, gabs);
785 num_dup_tsns = sctp_tsnmap_num_dups(map);
787 /* Initialize the SACK header. */
788 sack.cum_tsn_ack = htonl(ctsn);
789 sack.a_rwnd = htonl(asoc->a_rwnd);
790 sack.num_gap_ack_blocks = htons(num_gabs);
791 sack.num_dup_tsns = htons(num_dup_tsns);
794 + sizeof(struct sctp_gap_ack_block) * num_gabs
795 + sizeof(__u32) * num_dup_tsns;
797 /* Create the chunk. */
798 retval = sctp_make_control(asoc, SCTP_CID_SACK, 0, len, GFP_ATOMIC);
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 to
807 * which it is replying. This rule should also be followed if
808 * the endpoint is bundling DATA chunks together with the
811 * However, when acknowledging multiple DATA chunks received
812 * in packets from different source addresses in a single
813 * SACK, the SACK chunk may be transmitted to one of the
814 * destination transport addresses from which the DATA or
815 * control chunks being acknowledged were received.
817 * [BUG: We do not implement the following paragraph.
818 * Perhaps we should remember the last transport we used for a
819 * SACK and avoid that (if possible) if we have seen any
820 * duplicates. --piggy]
822 * When a receiver of a duplicate DATA chunk sends a SACK to a
823 * multi- homed endpoint it MAY be beneficial to vary the
824 * destination address and not use the source address of the
825 * DATA chunk. The reason being that receiving a duplicate
826 * from a multi-homed endpoint might indicate that the return
827 * path (as specified in the source address of the DATA chunk)
828 * for the SACK is broken.
830 * [Send to the address from which we last received a DATA chunk.]
832 retval->transport = asoc->peer.last_data_from;
834 retval->subh.sack_hdr =
835 sctp_addto_chunk(retval, sizeof(sack), &sack);
837 /* Add the gap ack block information. */
839 sctp_addto_chunk(retval, sizeof(__u32) * num_gabs,
842 /* Add the duplicate TSN information. */
844 aptr->stats.idupchunks += num_dup_tsns;
845 sctp_addto_chunk(retval, sizeof(__u32) * num_dup_tsns,
846 sctp_tsnmap_get_dups(map));
848 /* Once we have a sack generated, check to see what our sack
849 * generation is, if its 0, reset the transports to 0, and reset
850 * the association generation to 1
852 * The idea is that zero is never used as a valid generation for the
853 * association so no transport will match after a wrap event like this,
854 * Until the next sack
856 if (++aptr->peer.sack_generation == 0) {
857 list_for_each_entry(trans, &asoc->peer.transport_addr_list,
859 trans->sack_generation = 0;
860 aptr->peer.sack_generation = 1;
866 /* Make a SHUTDOWN chunk. */
867 struct sctp_chunk *sctp_make_shutdown(const struct sctp_association *asoc,
868 const struct sctp_chunk *chunk)
870 struct sctp_chunk *retval;
871 sctp_shutdownhdr_t shut;
874 ctsn = sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map);
875 shut.cum_tsn_ack = htonl(ctsn);
877 retval = sctp_make_control(asoc, SCTP_CID_SHUTDOWN, 0,
878 sizeof(sctp_shutdownhdr_t), GFP_ATOMIC);
882 retval->subh.shutdown_hdr =
883 sctp_addto_chunk(retval, sizeof(shut), &shut);
886 retval->transport = chunk->transport;
891 struct sctp_chunk *sctp_make_shutdown_ack(const struct sctp_association *asoc,
892 const struct sctp_chunk *chunk)
894 struct sctp_chunk *retval;
896 retval = sctp_make_control(asoc, SCTP_CID_SHUTDOWN_ACK, 0, 0,
899 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
901 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
902 * HEARTBEAT ACK, * etc.) to the same destination transport
903 * address from which it * received the DATA or control chunk
904 * to which it is replying.
906 * [ACK back to where the SHUTDOWN came from.]
909 retval->transport = chunk->transport;
914 struct sctp_chunk *sctp_make_shutdown_complete(
915 const struct sctp_association *asoc,
916 const struct sctp_chunk *chunk)
918 struct sctp_chunk *retval;
921 /* Set the T-bit if we have no association (vtag will be
924 flags |= asoc ? 0 : SCTP_CHUNK_FLAG_T;
926 retval = sctp_make_control(asoc, SCTP_CID_SHUTDOWN_COMPLETE, flags,
929 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
931 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
932 * HEARTBEAT ACK, * etc.) to the same destination transport
933 * address from which it * received the DATA or control chunk
934 * to which it is replying.
936 * [Report SHUTDOWN COMPLETE back to where the SHUTDOWN ACK
940 retval->transport = chunk->transport;
945 /* Create an ABORT. Note that we set the T bit if we have no
946 * association, except when responding to an INIT (sctpimpguide 2.41).
948 struct sctp_chunk *sctp_make_abort(const struct sctp_association *asoc,
949 const struct sctp_chunk *chunk,
952 struct sctp_chunk *retval;
955 /* Set the T-bit if we have no association and 'chunk' is not
956 * an INIT (vtag will be reflected).
959 if (chunk && chunk->chunk_hdr &&
960 chunk->chunk_hdr->type == SCTP_CID_INIT)
963 flags = SCTP_CHUNK_FLAG_T;
966 retval = sctp_make_control(asoc, SCTP_CID_ABORT, flags, hint,
969 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
971 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
972 * HEARTBEAT ACK, * etc.) to the same destination transport
973 * address from which it * received the DATA or control chunk
974 * to which it is replying.
976 * [ABORT back to where the offender came from.]
979 retval->transport = chunk->transport;
984 /* Helper to create ABORT with a NO_USER_DATA error. */
985 struct sctp_chunk *sctp_make_abort_no_data(
986 const struct sctp_association *asoc,
987 const struct sctp_chunk *chunk, __u32 tsn)
989 struct sctp_chunk *retval;
992 retval = sctp_make_abort(asoc, chunk, sizeof(sctp_errhdr_t)
998 /* Put the tsn back into network byte order. */
999 payload = htonl(tsn);
1000 sctp_init_cause(retval, SCTP_ERROR_NO_DATA, sizeof(payload));
1001 sctp_addto_chunk(retval, sizeof(payload), (const void *)&payload);
1003 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
1005 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
1006 * HEARTBEAT ACK, * etc.) to the same destination transport
1007 * address from which it * received the DATA or control chunk
1008 * to which it is replying.
1010 * [ABORT back to where the offender came from.]
1013 retval->transport = chunk->transport;
1019 /* Helper to create ABORT with a SCTP_ERROR_USER_ABORT error. */
1020 struct sctp_chunk *sctp_make_abort_user(const struct sctp_association *asoc,
1024 struct sctp_chunk *retval;
1025 void *payload = NULL;
1028 retval = sctp_make_abort(asoc, NULL, sizeof(sctp_errhdr_t) + paylen);
1033 /* Put the msg_iov together into payload. */
1034 payload = kmalloc(paylen, GFP_KERNEL);
1038 err = memcpy_from_msg(payload, msg, paylen);
1043 sctp_init_cause(retval, SCTP_ERROR_USER_ABORT, paylen);
1044 sctp_addto_chunk(retval, paylen, payload);
1054 sctp_chunk_free(retval);
1060 /* Append bytes to the end of a parameter. Will panic if chunk is not big
1063 static void *sctp_addto_param(struct sctp_chunk *chunk, int len,
1067 int chunklen = ntohs(chunk->chunk_hdr->length);
1069 target = skb_put(chunk->skb, len);
1072 memcpy(target, data, len);
1074 memset(target, 0, len);
1076 /* Adjust the chunk length field. */
1077 chunk->chunk_hdr->length = htons(chunklen + len);
1078 chunk->chunk_end = skb_tail_pointer(chunk->skb);
1083 /* Make an ABORT chunk with a PROTOCOL VIOLATION cause code. */
1084 struct sctp_chunk *sctp_make_abort_violation(
1085 const struct sctp_association *asoc,
1086 const struct sctp_chunk *chunk,
1087 const __u8 *payload,
1088 const size_t paylen)
1090 struct sctp_chunk *retval;
1091 struct sctp_paramhdr phdr;
1093 retval = sctp_make_abort(asoc, chunk, sizeof(sctp_errhdr_t) + paylen
1094 + sizeof(sctp_paramhdr_t));
1098 sctp_init_cause(retval, SCTP_ERROR_PROTO_VIOLATION, paylen
1099 + sizeof(sctp_paramhdr_t));
1101 phdr.type = htons(chunk->chunk_hdr->type);
1102 phdr.length = chunk->chunk_hdr->length;
1103 sctp_addto_chunk(retval, paylen, payload);
1104 sctp_addto_param(retval, sizeof(sctp_paramhdr_t), &phdr);
1110 struct sctp_chunk *sctp_make_violation_paramlen(
1111 const struct sctp_association *asoc,
1112 const struct sctp_chunk *chunk,
1113 struct sctp_paramhdr *param)
1115 struct sctp_chunk *retval;
1116 static const char error[] = "The following parameter had invalid length:";
1117 size_t payload_len = sizeof(error) + sizeof(sctp_errhdr_t) +
1118 sizeof(sctp_paramhdr_t);
1120 retval = sctp_make_abort(asoc, chunk, payload_len);
1124 sctp_init_cause(retval, SCTP_ERROR_PROTO_VIOLATION,
1125 sizeof(error) + sizeof(sctp_paramhdr_t));
1126 sctp_addto_chunk(retval, sizeof(error), error);
1127 sctp_addto_param(retval, sizeof(sctp_paramhdr_t), param);
1133 struct sctp_chunk *sctp_make_violation_max_retrans(
1134 const struct sctp_association *asoc,
1135 const struct sctp_chunk *chunk)
1137 struct sctp_chunk *retval;
1138 static const char error[] = "Association exceeded its max_retans count";
1139 size_t payload_len = sizeof(error) + sizeof(sctp_errhdr_t);
1141 retval = sctp_make_abort(asoc, chunk, payload_len);
1145 sctp_init_cause(retval, SCTP_ERROR_PROTO_VIOLATION, sizeof(error));
1146 sctp_addto_chunk(retval, sizeof(error), error);
1152 /* Make a HEARTBEAT chunk. */
1153 struct sctp_chunk *sctp_make_heartbeat(const struct sctp_association *asoc,
1154 const struct sctp_transport *transport)
1156 struct sctp_chunk *retval;
1157 sctp_sender_hb_info_t hbinfo;
1159 retval = sctp_make_control(asoc, SCTP_CID_HEARTBEAT, 0,
1160 sizeof(hbinfo), GFP_ATOMIC);
1165 hbinfo.param_hdr.type = SCTP_PARAM_HEARTBEAT_INFO;
1166 hbinfo.param_hdr.length = htons(sizeof(sctp_sender_hb_info_t));
1167 hbinfo.daddr = transport->ipaddr;
1168 hbinfo.sent_at = jiffies;
1169 hbinfo.hb_nonce = transport->hb_nonce;
1171 /* Cast away the 'const', as this is just telling the chunk
1172 * what transport it belongs to.
1174 retval->transport = (struct sctp_transport *) transport;
1175 retval->subh.hbs_hdr = sctp_addto_chunk(retval, sizeof(hbinfo),
1182 struct sctp_chunk *sctp_make_heartbeat_ack(const struct sctp_association *asoc,
1183 const struct sctp_chunk *chunk,
1184 const void *payload, const size_t paylen)
1186 struct sctp_chunk *retval;
1188 retval = sctp_make_control(asoc, SCTP_CID_HEARTBEAT_ACK, 0, paylen,
1193 retval->subh.hbs_hdr = sctp_addto_chunk(retval, paylen, payload);
1195 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
1197 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
1198 * HEARTBEAT ACK, * etc.) to the same destination transport
1199 * address from which it * received the DATA or control chunk
1200 * to which it is replying.
1202 * [HBACK back to where the HEARTBEAT came from.]
1205 retval->transport = chunk->transport;
1211 /* Create an Operation Error chunk with the specified space reserved.
1212 * This routine can be used for containing multiple causes in the chunk.
1214 static struct sctp_chunk *sctp_make_op_error_space(
1215 const struct sctp_association *asoc,
1216 const struct sctp_chunk *chunk,
1219 struct sctp_chunk *retval;
1221 retval = sctp_make_control(asoc, SCTP_CID_ERROR, 0,
1222 sizeof(sctp_errhdr_t) + size, GFP_ATOMIC);
1226 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
1228 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
1229 * HEARTBEAT ACK, etc.) to the same destination transport
1230 * address from which it received the DATA or control chunk
1231 * to which it is replying.
1235 retval->transport = chunk->transport;
1241 /* Create an Operation Error chunk of a fixed size,
1242 * specifically, max(asoc->pathmtu, SCTP_DEFAULT_MAXSEGMENT)
1243 * This is a helper function to allocate an error chunk for
1244 * for those invalid parameter codes in which we may not want
1245 * to report all the errors, if the incoming chunk is large
1247 static inline struct sctp_chunk *sctp_make_op_error_fixed(
1248 const struct sctp_association *asoc,
1249 const struct sctp_chunk *chunk)
1251 size_t size = asoc ? asoc->pathmtu : 0;
1254 size = SCTP_DEFAULT_MAXSEGMENT;
1256 return sctp_make_op_error_space(asoc, chunk, size);
1259 /* Create an Operation Error chunk. */
1260 struct sctp_chunk *sctp_make_op_error(const struct sctp_association *asoc,
1261 const struct sctp_chunk *chunk,
1262 __be16 cause_code, const void *payload,
1263 size_t paylen, size_t reserve_tail)
1265 struct sctp_chunk *retval;
1267 retval = sctp_make_op_error_space(asoc, chunk, paylen + reserve_tail);
1271 sctp_init_cause(retval, cause_code, paylen + reserve_tail);
1272 sctp_addto_chunk(retval, paylen, payload);
1274 sctp_addto_param(retval, reserve_tail, NULL);
1280 struct sctp_chunk *sctp_make_auth(const struct sctp_association *asoc)
1282 struct sctp_chunk *retval;
1283 struct sctp_hmac *hmac_desc;
1284 struct sctp_authhdr auth_hdr;
1287 /* Get the first hmac that the peer told us to use */
1288 hmac_desc = sctp_auth_asoc_get_hmac(asoc);
1289 if (unlikely(!hmac_desc))
1292 retval = sctp_make_control(asoc, SCTP_CID_AUTH, 0,
1293 hmac_desc->hmac_len + sizeof(sctp_authhdr_t),
1298 auth_hdr.hmac_id = htons(hmac_desc->hmac_id);
1299 auth_hdr.shkey_id = htons(asoc->active_key_id);
1301 retval->subh.auth_hdr = sctp_addto_chunk(retval, sizeof(sctp_authhdr_t),
1304 hmac = skb_put(retval->skb, hmac_desc->hmac_len);
1305 memset(hmac, 0, hmac_desc->hmac_len);
1307 /* Adjust the chunk header to include the empty MAC */
1308 retval->chunk_hdr->length =
1309 htons(ntohs(retval->chunk_hdr->length) + hmac_desc->hmac_len);
1310 retval->chunk_end = skb_tail_pointer(retval->skb);
1316 /********************************************************************
1317 * 2nd Level Abstractions
1318 ********************************************************************/
1320 /* Turn an skb into a chunk.
1321 * FIXME: Eventually move the structure directly inside the skb->cb[].
1323 * sctpimpguide-05.txt Section 2.8.2
1324 * M1) Each time a new DATA chunk is transmitted
1325 * set the 'TSN.Missing.Report' count for that TSN to 0. The
1326 * 'TSN.Missing.Report' count will be used to determine missing chunks
1327 * and when to fast retransmit.
1330 struct sctp_chunk *sctp_chunkify(struct sk_buff *skb,
1331 const struct sctp_association *asoc,
1332 struct sock *sk, gfp_t gfp)
1334 struct sctp_chunk *retval;
1336 retval = kmem_cache_zalloc(sctp_chunk_cachep, gfp);
1341 pr_debug("%s: chunkifying skb:%p w/o an sk\n", __func__, skb);
1343 INIT_LIST_HEAD(&retval->list);
1345 retval->asoc = (struct sctp_association *)asoc;
1346 retval->singleton = 1;
1348 retval->fast_retransmit = SCTP_CAN_FRTX;
1350 /* Polish the bead hole. */
1351 INIT_LIST_HEAD(&retval->transmitted_list);
1352 INIT_LIST_HEAD(&retval->frag_list);
1353 SCTP_DBG_OBJCNT_INC(chunk);
1354 atomic_set(&retval->refcnt, 1);
1360 /* Set chunk->source and dest based on the IP header in chunk->skb. */
1361 void sctp_init_addrs(struct sctp_chunk *chunk, union sctp_addr *src,
1362 union sctp_addr *dest)
1364 memcpy(&chunk->source, src, sizeof(union sctp_addr));
1365 memcpy(&chunk->dest, dest, sizeof(union sctp_addr));
1368 /* Extract the source address from a chunk. */
1369 const union sctp_addr *sctp_source(const struct sctp_chunk *chunk)
1371 /* If we have a known transport, use that. */
1372 if (chunk->transport) {
1373 return &chunk->transport->ipaddr;
1375 /* Otherwise, extract it from the IP header. */
1376 return &chunk->source;
1380 /* Create a new chunk, setting the type and flags headers from the
1381 * arguments, reserving enough space for a 'paylen' byte payload.
1383 static struct sctp_chunk *_sctp_make_chunk(const struct sctp_association *asoc,
1384 __u8 type, __u8 flags, int paylen,
1387 struct sctp_chunk *retval;
1388 sctp_chunkhdr_t *chunk_hdr;
1389 struct sk_buff *skb;
1392 /* No need to allocate LL here, as this is only a chunk. */
1393 skb = alloc_skb(WORD_ROUND(sizeof(sctp_chunkhdr_t) + paylen), gfp);
1397 /* Make room for the chunk header. */
1398 chunk_hdr = (sctp_chunkhdr_t *)skb_put(skb, sizeof(sctp_chunkhdr_t));
1399 chunk_hdr->type = type;
1400 chunk_hdr->flags = flags;
1401 chunk_hdr->length = htons(sizeof(sctp_chunkhdr_t));
1403 sk = asoc ? asoc->base.sk : NULL;
1404 retval = sctp_chunkify(skb, asoc, sk, gfp);
1410 retval->chunk_hdr = chunk_hdr;
1411 retval->chunk_end = ((__u8 *)chunk_hdr) + sizeof(struct sctp_chunkhdr);
1413 /* Determine if the chunk needs to be authenticated */
1414 if (sctp_auth_send_cid(type, asoc))
1422 static struct sctp_chunk *sctp_make_data(const struct sctp_association *asoc,
1423 __u8 flags, int paylen, gfp_t gfp)
1425 return _sctp_make_chunk(asoc, SCTP_CID_DATA, flags, paylen, gfp);
1428 static struct sctp_chunk *sctp_make_control(const struct sctp_association *asoc,
1429 __u8 type, __u8 flags, int paylen,
1432 struct sctp_chunk *chunk;
1434 chunk = _sctp_make_chunk(asoc, type, flags, paylen, gfp);
1436 sctp_control_set_owner_w(chunk);
1441 /* Release the memory occupied by a chunk. */
1442 static void sctp_chunk_destroy(struct sctp_chunk *chunk)
1444 BUG_ON(!list_empty(&chunk->list));
1445 list_del_init(&chunk->transmitted_list);
1447 consume_skb(chunk->skb);
1448 consume_skb(chunk->auth_chunk);
1450 SCTP_DBG_OBJCNT_DEC(chunk);
1451 kmem_cache_free(sctp_chunk_cachep, chunk);
1454 /* Possibly, free the chunk. */
1455 void sctp_chunk_free(struct sctp_chunk *chunk)
1457 /* Release our reference on the message tracker. */
1459 sctp_datamsg_put(chunk->msg);
1461 sctp_chunk_put(chunk);
1464 /* Grab a reference to the chunk. */
1465 void sctp_chunk_hold(struct sctp_chunk *ch)
1467 atomic_inc(&ch->refcnt);
1470 /* Release a reference to the chunk. */
1471 void sctp_chunk_put(struct sctp_chunk *ch)
1473 if (atomic_dec_and_test(&ch->refcnt))
1474 sctp_chunk_destroy(ch);
1477 /* Append bytes to the end of a chunk. Will panic if chunk is not big
1480 void *sctp_addto_chunk(struct sctp_chunk *chunk, int len, const void *data)
1484 int chunklen = ntohs(chunk->chunk_hdr->length);
1485 int padlen = WORD_ROUND(chunklen) - chunklen;
1487 padding = skb_put(chunk->skb, padlen);
1488 target = skb_put(chunk->skb, len);
1490 memset(padding, 0, padlen);
1491 memcpy(target, data, len);
1493 /* Adjust the chunk length field. */
1494 chunk->chunk_hdr->length = htons(chunklen + padlen + len);
1495 chunk->chunk_end = skb_tail_pointer(chunk->skb);
1500 /* Append bytes to the end of a chunk. Returns NULL if there isn't sufficient
1501 * space in the chunk
1503 static void *sctp_addto_chunk_fixed(struct sctp_chunk *chunk,
1504 int len, const void *data)
1506 if (skb_tailroom(chunk->skb) >= len)
1507 return sctp_addto_chunk(chunk, len, data);
1512 /* Append bytes from user space to the end of a chunk. Will panic if
1513 * chunk is not big enough.
1514 * Returns a kernel err value.
1516 int sctp_user_addto_chunk(struct sctp_chunk *chunk, int len,
1517 struct iov_iter *from)
1522 /* Make room in chunk for data. */
1523 target = skb_put(chunk->skb, len);
1525 /* Copy data (whole iovec) into chunk */
1526 copied = copy_from_iter(target, len, from);
1530 /* Adjust the chunk length field. */
1531 chunk->chunk_hdr->length =
1532 htons(ntohs(chunk->chunk_hdr->length) + len);
1533 chunk->chunk_end = skb_tail_pointer(chunk->skb);
1538 /* Helper function to assign a TSN if needed. This assumes that both
1539 * the data_hdr and association have already been assigned.
1541 void sctp_chunk_assign_ssn(struct sctp_chunk *chunk)
1543 struct sctp_datamsg *msg;
1544 struct sctp_chunk *lchunk;
1545 struct sctp_stream *stream;
1552 /* All fragments will be on the same stream */
1553 sid = ntohs(chunk->subh.data_hdr->stream);
1554 stream = &chunk->asoc->ssnmap->out;
1556 /* Now assign the sequence number to the entire message.
1557 * All fragments must have the same stream sequence number.
1560 list_for_each_entry(lchunk, &msg->chunks, frag_list) {
1561 if (lchunk->chunk_hdr->flags & SCTP_DATA_UNORDERED) {
1564 if (lchunk->chunk_hdr->flags & SCTP_DATA_LAST_FRAG)
1565 ssn = sctp_ssn_next(stream, sid);
1567 ssn = sctp_ssn_peek(stream, sid);
1570 lchunk->subh.data_hdr->ssn = htons(ssn);
1571 lchunk->has_ssn = 1;
1575 /* Helper function to assign a TSN if needed. This assumes that both
1576 * the data_hdr and association have already been assigned.
1578 void sctp_chunk_assign_tsn(struct sctp_chunk *chunk)
1580 if (!chunk->has_tsn) {
1581 /* This is the last possible instant to
1584 chunk->subh.data_hdr->tsn =
1585 htonl(sctp_association_get_next_tsn(chunk->asoc));
1590 /* Create a CLOSED association to use with an incoming packet. */
1591 struct sctp_association *sctp_make_temp_asoc(const struct sctp_endpoint *ep,
1592 struct sctp_chunk *chunk,
1595 struct sctp_association *asoc;
1596 struct sk_buff *skb;
1599 /* Create the bare association. */
1600 scope = sctp_scope(sctp_source(chunk));
1601 asoc = sctp_association_new(ep, ep->base.sk, scope, gfp);
1606 /* Create an entry for the source address of the packet. */
1607 SCTP_INPUT_CB(skb)->af->from_skb(&asoc->c.peer_addr, skb, 1);
1613 /* Build a cookie representing asoc.
1614 * This INCLUDES the param header needed to put the cookie in the INIT ACK.
1616 static sctp_cookie_param_t *sctp_pack_cookie(const struct sctp_endpoint *ep,
1617 const struct sctp_association *asoc,
1618 const struct sctp_chunk *init_chunk,
1620 const __u8 *raw_addrs, int addrs_len)
1622 sctp_cookie_param_t *retval;
1623 struct sctp_signed_cookie *cookie;
1624 int headersize, bodysize;
1626 /* Header size is static data prior to the actual cookie, including
1629 headersize = sizeof(sctp_paramhdr_t) +
1630 (sizeof(struct sctp_signed_cookie) -
1631 sizeof(struct sctp_cookie));
1632 bodysize = sizeof(struct sctp_cookie)
1633 + ntohs(init_chunk->chunk_hdr->length) + addrs_len;
1635 /* Pad out the cookie to a multiple to make the signature
1636 * functions simpler to write.
1638 if (bodysize % SCTP_COOKIE_MULTIPLE)
1639 bodysize += SCTP_COOKIE_MULTIPLE
1640 - (bodysize % SCTP_COOKIE_MULTIPLE);
1641 *cookie_len = headersize + bodysize;
1643 /* Clear this memory since we are sending this data structure
1644 * out on the network.
1646 retval = kzalloc(*cookie_len, GFP_ATOMIC);
1650 cookie = (struct sctp_signed_cookie *) retval->body;
1652 /* Set up the parameter header. */
1653 retval->p.type = SCTP_PARAM_STATE_COOKIE;
1654 retval->p.length = htons(*cookie_len);
1656 /* Copy the cookie part of the association itself. */
1657 cookie->c = asoc->c;
1658 /* Save the raw address list length in the cookie. */
1659 cookie->c.raw_addr_list_len = addrs_len;
1661 /* Remember PR-SCTP capability. */
1662 cookie->c.prsctp_capable = asoc->peer.prsctp_capable;
1664 /* Save adaptation indication in the cookie. */
1665 cookie->c.adaptation_ind = asoc->peer.adaptation_ind;
1667 /* Set an expiration time for the cookie. */
1668 cookie->c.expiration = ktime_add(asoc->cookie_life,
1671 /* Copy the peer's init packet. */
1672 memcpy(&cookie->c.peer_init[0], init_chunk->chunk_hdr,
1673 ntohs(init_chunk->chunk_hdr->length));
1675 /* Copy the raw local address list of the association. */
1676 memcpy((__u8 *)&cookie->c.peer_init[0] +
1677 ntohs(init_chunk->chunk_hdr->length), raw_addrs, addrs_len);
1679 if (sctp_sk(ep->base.sk)->hmac) {
1680 SHASH_DESC_ON_STACK(desc, sctp_sk(ep->base.sk)->hmac);
1683 /* Sign the message. */
1684 desc->tfm = sctp_sk(ep->base.sk)->hmac;
1687 err = crypto_shash_setkey(desc->tfm, ep->secret_key,
1688 sizeof(ep->secret_key)) ?:
1689 crypto_shash_digest(desc, (u8 *)&cookie->c, bodysize,
1691 shash_desc_zero(desc);
1705 /* Unpack the cookie from COOKIE ECHO chunk, recreating the association. */
1706 struct sctp_association *sctp_unpack_cookie(
1707 const struct sctp_endpoint *ep,
1708 const struct sctp_association *asoc,
1709 struct sctp_chunk *chunk, gfp_t gfp,
1710 int *error, struct sctp_chunk **errp)
1712 struct sctp_association *retval = NULL;
1713 struct sctp_signed_cookie *cookie;
1714 struct sctp_cookie *bear_cookie;
1715 int headersize, bodysize, fixed_size;
1716 __u8 *digest = ep->digest;
1719 struct sk_buff *skb = chunk->skb;
1722 /* Header size is static data prior to the actual cookie, including
1725 headersize = sizeof(sctp_chunkhdr_t) +
1726 (sizeof(struct sctp_signed_cookie) -
1727 sizeof(struct sctp_cookie));
1728 bodysize = ntohs(chunk->chunk_hdr->length) - headersize;
1729 fixed_size = headersize + sizeof(struct sctp_cookie);
1731 /* Verify that the chunk looks like it even has a cookie.
1732 * There must be enough room for our cookie and our peer's
1735 len = ntohs(chunk->chunk_hdr->length);
1736 if (len < fixed_size + sizeof(struct sctp_chunkhdr))
1739 /* Verify that the cookie has been padded out. */
1740 if (bodysize % SCTP_COOKIE_MULTIPLE)
1743 /* Process the cookie. */
1744 cookie = chunk->subh.cookie_hdr;
1745 bear_cookie = &cookie->c;
1747 if (!sctp_sk(ep->base.sk)->hmac)
1750 /* Check the signature. */
1752 SHASH_DESC_ON_STACK(desc, sctp_sk(ep->base.sk)->hmac);
1755 desc->tfm = sctp_sk(ep->base.sk)->hmac;
1758 err = crypto_shash_setkey(desc->tfm, ep->secret_key,
1759 sizeof(ep->secret_key)) ?:
1760 crypto_shash_digest(desc, (u8 *)bear_cookie, bodysize,
1762 shash_desc_zero(desc);
1765 *error = -SCTP_IERROR_NOMEM;
1770 if (memcmp(digest, cookie->signature, SCTP_SIGNATURE_SIZE)) {
1771 *error = -SCTP_IERROR_BAD_SIG;
1776 /* IG Section 2.35.2:
1777 * 3) Compare the port numbers and the verification tag contained
1778 * within the COOKIE ECHO chunk to the actual port numbers and the
1779 * verification tag within the SCTP common header of the received
1780 * packet. If these values do not match the packet MUST be silently
1783 if (ntohl(chunk->sctp_hdr->vtag) != bear_cookie->my_vtag) {
1784 *error = -SCTP_IERROR_BAD_TAG;
1788 if (chunk->sctp_hdr->source != bear_cookie->peer_addr.v4.sin_port ||
1789 ntohs(chunk->sctp_hdr->dest) != bear_cookie->my_port) {
1790 *error = -SCTP_IERROR_BAD_PORTS;
1794 /* Check to see if the cookie is stale. If there is already
1795 * an association, there is no need to check cookie's expiration
1796 * for init collision case of lost COOKIE ACK.
1797 * If skb has been timestamped, then use the stamp, otherwise
1798 * use current time. This introduces a small possibility that
1799 * that a cookie may be considered expired, but his would only slow
1800 * down the new association establishment instead of every packet.
1802 if (sock_flag(ep->base.sk, SOCK_TIMESTAMP))
1803 kt = skb_get_ktime(skb);
1805 kt = ktime_get_real();
1807 if (!asoc && ktime_before(bear_cookie->expiration, kt)) {
1809 * Section 3.3.10.3 Stale Cookie Error (3)
1813 * Stale Cookie Error: Indicates the receipt of a valid State
1814 * Cookie that has expired.
1816 len = ntohs(chunk->chunk_hdr->length);
1817 *errp = sctp_make_op_error_space(asoc, chunk, len);
1819 suseconds_t usecs = ktime_to_us(ktime_sub(kt, bear_cookie->expiration));
1820 __be32 n = htonl(usecs);
1822 sctp_init_cause(*errp, SCTP_ERROR_STALE_COOKIE,
1824 sctp_addto_chunk(*errp, sizeof(n), &n);
1825 *error = -SCTP_IERROR_STALE_COOKIE;
1827 *error = -SCTP_IERROR_NOMEM;
1832 /* Make a new base association. */
1833 scope = sctp_scope(sctp_source(chunk));
1834 retval = sctp_association_new(ep, ep->base.sk, scope, gfp);
1836 *error = -SCTP_IERROR_NOMEM;
1840 /* Set up our peer's port number. */
1841 retval->peer.port = ntohs(chunk->sctp_hdr->source);
1843 /* Populate the association from the cookie. */
1844 memcpy(&retval->c, bear_cookie, sizeof(*bear_cookie));
1846 if (sctp_assoc_set_bind_addr_from_cookie(retval, bear_cookie,
1848 *error = -SCTP_IERROR_NOMEM;
1852 /* Also, add the destination address. */
1853 if (list_empty(&retval->base.bind_addr.address_list)) {
1854 sctp_add_bind_addr(&retval->base.bind_addr, &chunk->dest,
1855 sizeof(chunk->dest), SCTP_ADDR_SRC,
1859 retval->next_tsn = retval->c.initial_tsn;
1860 retval->ctsn_ack_point = retval->next_tsn - 1;
1861 retval->addip_serial = retval->c.initial_tsn;
1862 retval->adv_peer_ack_point = retval->ctsn_ack_point;
1863 retval->peer.prsctp_capable = retval->c.prsctp_capable;
1864 retval->peer.adaptation_ind = retval->c.adaptation_ind;
1866 /* The INIT stuff will be done by the side effects. */
1871 sctp_association_free(retval);
1876 /* Yikes! The packet is either corrupt or deliberately
1879 *error = -SCTP_IERROR_MALFORMED;
1883 /********************************************************************
1884 * 3rd Level Abstractions
1885 ********************************************************************/
1887 struct __sctp_missing {
1893 * Report a missing mandatory parameter.
1895 static int sctp_process_missing_param(const struct sctp_association *asoc,
1896 sctp_param_t paramtype,
1897 struct sctp_chunk *chunk,
1898 struct sctp_chunk **errp)
1900 struct __sctp_missing report;
1903 len = WORD_ROUND(sizeof(report));
1905 /* Make an ERROR chunk, preparing enough room for
1906 * returning multiple unknown parameters.
1909 *errp = sctp_make_op_error_space(asoc, chunk, len);
1912 report.num_missing = htonl(1);
1913 report.type = paramtype;
1914 sctp_init_cause(*errp, SCTP_ERROR_MISS_PARAM,
1916 sctp_addto_chunk(*errp, sizeof(report), &report);
1919 /* Stop processing this chunk. */
1923 /* Report an Invalid Mandatory Parameter. */
1924 static int sctp_process_inv_mandatory(const struct sctp_association *asoc,
1925 struct sctp_chunk *chunk,
1926 struct sctp_chunk **errp)
1928 /* Invalid Mandatory Parameter Error has no payload. */
1931 *errp = sctp_make_op_error_space(asoc, chunk, 0);
1934 sctp_init_cause(*errp, SCTP_ERROR_INV_PARAM, 0);
1936 /* Stop processing this chunk. */
1940 static int sctp_process_inv_paramlength(const struct sctp_association *asoc,
1941 struct sctp_paramhdr *param,
1942 const struct sctp_chunk *chunk,
1943 struct sctp_chunk **errp)
1945 /* This is a fatal error. Any accumulated non-fatal errors are
1949 sctp_chunk_free(*errp);
1951 /* Create an error chunk and fill it in with our payload. */
1952 *errp = sctp_make_violation_paramlen(asoc, chunk, param);
1958 /* Do not attempt to handle the HOST_NAME parm. However, do
1959 * send back an indicator to the peer.
1961 static int sctp_process_hn_param(const struct sctp_association *asoc,
1962 union sctp_params param,
1963 struct sctp_chunk *chunk,
1964 struct sctp_chunk **errp)
1966 __u16 len = ntohs(param.p->length);
1968 /* Processing of the HOST_NAME parameter will generate an
1969 * ABORT. If we've accumulated any non-fatal errors, they
1970 * would be unrecognized parameters and we should not include
1971 * them in the ABORT.
1974 sctp_chunk_free(*errp);
1976 *errp = sctp_make_op_error_space(asoc, chunk, len);
1979 sctp_init_cause(*errp, SCTP_ERROR_DNS_FAILED, len);
1980 sctp_addto_chunk(*errp, len, param.v);
1983 /* Stop processing this chunk. */
1987 static int sctp_verify_ext_param(struct net *net, union sctp_params param)
1989 __u16 num_ext = ntohs(param.p->length) - sizeof(sctp_paramhdr_t);
1991 int have_asconf = 0;
1994 for (i = 0; i < num_ext; i++) {
1995 switch (param.ext->chunks[i]) {
1999 case SCTP_CID_ASCONF:
2000 case SCTP_CID_ASCONF_ACK:
2006 /* ADD-IP Security: The draft requires us to ABORT or ignore the
2007 * INIT/INIT-ACK if ADD-IP is listed, but AUTH is not. Do this
2008 * only if ADD-IP is turned on and we are not backward-compatible
2011 if (net->sctp.addip_noauth)
2014 if (net->sctp.addip_enable && !have_auth && have_asconf)
2020 static void sctp_process_ext_param(struct sctp_association *asoc,
2021 union sctp_params param)
2023 struct net *net = sock_net(asoc->base.sk);
2024 __u16 num_ext = ntohs(param.p->length) - sizeof(sctp_paramhdr_t);
2027 for (i = 0; i < num_ext; i++) {
2028 switch (param.ext->chunks[i]) {
2029 case SCTP_CID_FWD_TSN:
2030 if (asoc->prsctp_enable && !asoc->peer.prsctp_capable)
2031 asoc->peer.prsctp_capable = 1;
2034 /* if the peer reports AUTH, assume that he
2037 if (asoc->ep->auth_enable)
2038 asoc->peer.auth_capable = 1;
2040 case SCTP_CID_ASCONF:
2041 case SCTP_CID_ASCONF_ACK:
2042 if (net->sctp.addip_enable)
2043 asoc->peer.asconf_capable = 1;
2051 /* RFC 3.2.1 & the Implementers Guide 2.2.
2053 * The Parameter Types are encoded such that the
2054 * highest-order two bits specify the action that must be
2055 * taken if the processing endpoint does not recognize the
2058 * 00 - Stop processing this parameter; do not process any further
2059 * parameters within this chunk
2061 * 01 - Stop processing this parameter, do not process any further
2062 * parameters within this chunk, and report the unrecognized
2063 * parameter in an 'Unrecognized Parameter' ERROR chunk.
2065 * 10 - Skip this parameter and continue processing.
2067 * 11 - Skip this parameter and continue processing but
2068 * report the unrecognized parameter in an
2069 * 'Unrecognized Parameter' ERROR chunk.
2072 * SCTP_IERROR_NO_ERROR - continue with the chunk
2073 * SCTP_IERROR_ERROR - stop and report an error.
2074 * SCTP_IERROR_NOMEME - out of memory.
2076 static sctp_ierror_t sctp_process_unk_param(const struct sctp_association *asoc,
2077 union sctp_params param,
2078 struct sctp_chunk *chunk,
2079 struct sctp_chunk **errp)
2081 int retval = SCTP_IERROR_NO_ERROR;
2083 switch (param.p->type & SCTP_PARAM_ACTION_MASK) {
2084 case SCTP_PARAM_ACTION_DISCARD:
2085 retval = SCTP_IERROR_ERROR;
2087 case SCTP_PARAM_ACTION_SKIP:
2089 case SCTP_PARAM_ACTION_DISCARD_ERR:
2090 retval = SCTP_IERROR_ERROR;
2092 case SCTP_PARAM_ACTION_SKIP_ERR:
2093 /* Make an ERROR chunk, preparing enough room for
2094 * returning multiple unknown parameters.
2097 *errp = sctp_make_op_error_fixed(asoc, chunk);
2100 if (!sctp_init_cause_fixed(*errp, SCTP_ERROR_UNKNOWN_PARAM,
2101 WORD_ROUND(ntohs(param.p->length))))
2102 sctp_addto_chunk_fixed(*errp,
2103 WORD_ROUND(ntohs(param.p->length)),
2106 /* If there is no memory for generating the ERROR
2107 * report as specified, an ABORT will be triggered
2108 * to the peer and the association won't be
2111 retval = SCTP_IERROR_NOMEM;
2121 /* Verify variable length parameters
2123 * SCTP_IERROR_ABORT - trigger an ABORT
2124 * SCTP_IERROR_NOMEM - out of memory (abort)
2125 * SCTP_IERROR_ERROR - stop processing, trigger an ERROR
2126 * SCTP_IERROR_NO_ERROR - continue with the chunk
2128 static sctp_ierror_t sctp_verify_param(struct net *net,
2129 const struct sctp_endpoint *ep,
2130 const struct sctp_association *asoc,
2131 union sctp_params param,
2133 struct sctp_chunk *chunk,
2134 struct sctp_chunk **err_chunk)
2136 struct sctp_hmac_algo_param *hmacs;
2137 int retval = SCTP_IERROR_NO_ERROR;
2138 __u16 n_elt, id = 0;
2141 /* FIXME - This routine is not looking at each parameter per the
2142 * chunk type, i.e., unrecognized parameters should be further
2143 * identified based on the chunk id.
2146 switch (param.p->type) {
2147 case SCTP_PARAM_IPV4_ADDRESS:
2148 case SCTP_PARAM_IPV6_ADDRESS:
2149 case SCTP_PARAM_COOKIE_PRESERVATIVE:
2150 case SCTP_PARAM_SUPPORTED_ADDRESS_TYPES:
2151 case SCTP_PARAM_STATE_COOKIE:
2152 case SCTP_PARAM_HEARTBEAT_INFO:
2153 case SCTP_PARAM_UNRECOGNIZED_PARAMETERS:
2154 case SCTP_PARAM_ECN_CAPABLE:
2155 case SCTP_PARAM_ADAPTATION_LAYER_IND:
2158 case SCTP_PARAM_SUPPORTED_EXT:
2159 if (!sctp_verify_ext_param(net, param))
2160 return SCTP_IERROR_ABORT;
2163 case SCTP_PARAM_SET_PRIMARY:
2164 if (net->sctp.addip_enable)
2168 case SCTP_PARAM_HOST_NAME_ADDRESS:
2169 /* Tell the peer, we won't support this param. */
2170 sctp_process_hn_param(asoc, param, chunk, err_chunk);
2171 retval = SCTP_IERROR_ABORT;
2174 case SCTP_PARAM_FWD_TSN_SUPPORT:
2175 if (ep->prsctp_enable)
2179 case SCTP_PARAM_RANDOM:
2180 if (!ep->auth_enable)
2183 /* SCTP-AUTH: Secion 6.1
2184 * If the random number is not 32 byte long the association
2185 * MUST be aborted. The ABORT chunk SHOULD contain the error
2186 * cause 'Protocol Violation'.
2188 if (SCTP_AUTH_RANDOM_LENGTH !=
2189 ntohs(param.p->length) - sizeof(sctp_paramhdr_t)) {
2190 sctp_process_inv_paramlength(asoc, param.p,
2192 retval = SCTP_IERROR_ABORT;
2196 case SCTP_PARAM_CHUNKS:
2197 if (!ep->auth_enable)
2200 /* SCTP-AUTH: Section 3.2
2201 * The CHUNKS parameter MUST be included once in the INIT or
2202 * INIT-ACK chunk if the sender wants to receive authenticated
2203 * chunks. Its maximum length is 260 bytes.
2205 if (260 < ntohs(param.p->length)) {
2206 sctp_process_inv_paramlength(asoc, param.p,
2208 retval = SCTP_IERROR_ABORT;
2212 case SCTP_PARAM_HMAC_ALGO:
2213 if (!ep->auth_enable)
2216 hmacs = (struct sctp_hmac_algo_param *)param.p;
2217 n_elt = (ntohs(param.p->length) - sizeof(sctp_paramhdr_t)) >> 1;
2219 /* SCTP-AUTH: Section 6.1
2220 * The HMAC algorithm based on SHA-1 MUST be supported and
2221 * included in the HMAC-ALGO parameter.
2223 for (i = 0; i < n_elt; i++) {
2224 id = ntohs(hmacs->hmac_ids[i]);
2226 if (id == SCTP_AUTH_HMAC_ID_SHA1)
2230 if (id != SCTP_AUTH_HMAC_ID_SHA1) {
2231 sctp_process_inv_paramlength(asoc, param.p, chunk,
2233 retval = SCTP_IERROR_ABORT;
2238 pr_debug("%s: unrecognized param:%d for chunk:%d\n",
2239 __func__, ntohs(param.p->type), cid);
2241 retval = sctp_process_unk_param(asoc, param, chunk, err_chunk);
2247 /* Verify the INIT packet before we process it. */
2248 int sctp_verify_init(struct net *net, const struct sctp_endpoint *ep,
2249 const struct sctp_association *asoc, sctp_cid_t cid,
2250 sctp_init_chunk_t *peer_init, struct sctp_chunk *chunk,
2251 struct sctp_chunk **errp)
2253 union sctp_params param;
2254 bool has_cookie = false;
2257 /* Check for missing mandatory parameters. Note: Initial TSN is
2258 * also mandatory, but is not checked here since the valid range
2259 * is 0..2**32-1. RFC4960, section 3.3.3.
2261 if (peer_init->init_hdr.num_outbound_streams == 0 ||
2262 peer_init->init_hdr.num_inbound_streams == 0 ||
2263 peer_init->init_hdr.init_tag == 0 ||
2264 ntohl(peer_init->init_hdr.a_rwnd) < SCTP_DEFAULT_MINWINDOW)
2265 return sctp_process_inv_mandatory(asoc, chunk, errp);
2267 sctp_walk_params(param, peer_init, init_hdr.params) {
2268 if (param.p->type == SCTP_PARAM_STATE_COOKIE)
2272 /* There is a possibility that a parameter length was bad and
2273 * in that case we would have stoped walking the parameters.
2274 * The current param.p would point at the bad one.
2275 * Current consensus on the mailing list is to generate a PROTOCOL
2276 * VIOLATION error. We build the ERROR chunk here and let the normal
2277 * error handling code build and send the packet.
2279 if (param.v != (void *)chunk->chunk_end)
2280 return sctp_process_inv_paramlength(asoc, param.p, chunk, errp);
2282 /* The only missing mandatory param possible today is
2283 * the state cookie for an INIT-ACK chunk.
2285 if ((SCTP_CID_INIT_ACK == cid) && !has_cookie)
2286 return sctp_process_missing_param(asoc, SCTP_PARAM_STATE_COOKIE,
2289 /* Verify all the variable length parameters */
2290 sctp_walk_params(param, peer_init, init_hdr.params) {
2291 result = sctp_verify_param(net, ep, asoc, param, cid,
2294 case SCTP_IERROR_ABORT:
2295 case SCTP_IERROR_NOMEM:
2297 case SCTP_IERROR_ERROR:
2299 case SCTP_IERROR_NO_ERROR:
2304 } /* for (loop through all parameters) */
2309 /* Unpack the parameters in an INIT packet into an association.
2310 * Returns 0 on failure, else success.
2311 * FIXME: This is an association method.
2313 int sctp_process_init(struct sctp_association *asoc, struct sctp_chunk *chunk,
2314 const union sctp_addr *peer_addr,
2315 sctp_init_chunk_t *peer_init, gfp_t gfp)
2317 struct net *net = sock_net(asoc->base.sk);
2318 union sctp_params param;
2319 struct sctp_transport *transport;
2320 struct list_head *pos, *temp;
2322 union sctp_addr addr;
2326 /* We must include the address that the INIT packet came from.
2327 * This is the only address that matters for an INIT packet.
2328 * When processing a COOKIE ECHO, we retrieve the from address
2329 * of the INIT from the cookie.
2332 /* This implementation defaults to making the first transport
2333 * added as the primary transport. The source address seems to
2334 * be a a better choice than any of the embedded addresses.
2336 if (!sctp_assoc_add_peer(asoc, peer_addr, gfp, SCTP_ACTIVE))
2339 if (sctp_cmp_addr_exact(sctp_source(chunk), peer_addr))
2342 /* Process the initialization parameters. */
2343 sctp_walk_params(param, peer_init, init_hdr.params) {
2344 if (!src_match && (param.p->type == SCTP_PARAM_IPV4_ADDRESS ||
2345 param.p->type == SCTP_PARAM_IPV6_ADDRESS)) {
2346 af = sctp_get_af_specific(param_type2af(param.p->type));
2347 af->from_addr_param(&addr, param.addr,
2348 chunk->sctp_hdr->source, 0);
2349 if (sctp_cmp_addr_exact(sctp_source(chunk), &addr))
2353 if (!sctp_process_param(asoc, param, peer_addr, gfp))
2357 /* source address of chunk may not match any valid address */
2361 /* AUTH: After processing the parameters, make sure that we
2362 * have all the required info to potentially do authentications.
2364 if (asoc->peer.auth_capable && (!asoc->peer.peer_random ||
2365 !asoc->peer.peer_hmacs))
2366 asoc->peer.auth_capable = 0;
2368 /* In a non-backward compatible mode, if the peer claims
2369 * support for ADD-IP but not AUTH, the ADD-IP spec states
2370 * that we MUST ABORT the association. Section 6. The section
2371 * also give us an option to silently ignore the packet, which
2372 * is what we'll do here.
2374 if (!net->sctp.addip_noauth &&
2375 (asoc->peer.asconf_capable && !asoc->peer.auth_capable)) {
2376 asoc->peer.addip_disabled_mask |= (SCTP_PARAM_ADD_IP |
2378 SCTP_PARAM_SET_PRIMARY);
2379 asoc->peer.asconf_capable = 0;
2383 /* Walk list of transports, removing transports in the UNKNOWN state. */
2384 list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
2385 transport = list_entry(pos, struct sctp_transport, transports);
2386 if (transport->state == SCTP_UNKNOWN) {
2387 sctp_assoc_rm_peer(asoc, transport);
2391 /* The fixed INIT headers are always in network byte
2394 asoc->peer.i.init_tag =
2395 ntohl(peer_init->init_hdr.init_tag);
2396 asoc->peer.i.a_rwnd =
2397 ntohl(peer_init->init_hdr.a_rwnd);
2398 asoc->peer.i.num_outbound_streams =
2399 ntohs(peer_init->init_hdr.num_outbound_streams);
2400 asoc->peer.i.num_inbound_streams =
2401 ntohs(peer_init->init_hdr.num_inbound_streams);
2402 asoc->peer.i.initial_tsn =
2403 ntohl(peer_init->init_hdr.initial_tsn);
2405 /* Apply the upper bounds for output streams based on peer's
2406 * number of inbound streams.
2408 if (asoc->c.sinit_num_ostreams >
2409 ntohs(peer_init->init_hdr.num_inbound_streams)) {
2410 asoc->c.sinit_num_ostreams =
2411 ntohs(peer_init->init_hdr.num_inbound_streams);
2414 if (asoc->c.sinit_max_instreams >
2415 ntohs(peer_init->init_hdr.num_outbound_streams)) {
2416 asoc->c.sinit_max_instreams =
2417 ntohs(peer_init->init_hdr.num_outbound_streams);
2420 /* Copy Initiation tag from INIT to VT_peer in cookie. */
2421 asoc->c.peer_vtag = asoc->peer.i.init_tag;
2423 /* Peer Rwnd : Current calculated value of the peer's rwnd. */
2424 asoc->peer.rwnd = asoc->peer.i.a_rwnd;
2426 /* Copy cookie in case we need to resend COOKIE-ECHO. */
2427 cookie = asoc->peer.cookie;
2429 asoc->peer.cookie = kmemdup(cookie, asoc->peer.cookie_len, gfp);
2430 if (!asoc->peer.cookie)
2434 /* RFC 2960 7.2.1 The initial value of ssthresh MAY be arbitrarily
2435 * high (for example, implementations MAY use the size of the receiver
2436 * advertised window).
2438 list_for_each_entry(transport, &asoc->peer.transport_addr_list,
2440 transport->ssthresh = asoc->peer.i.a_rwnd;
2443 /* Set up the TSN tracking pieces. */
2444 if (!sctp_tsnmap_init(&asoc->peer.tsn_map, SCTP_TSN_MAP_INITIAL,
2445 asoc->peer.i.initial_tsn, gfp))
2448 /* RFC 2960 6.5 Stream Identifier and Stream Sequence Number
2450 * The stream sequence number in all the streams shall start
2451 * from 0 when the association is established. Also, when the
2452 * stream sequence number reaches the value 65535 the next
2453 * stream sequence number shall be set to 0.
2456 /* Allocate storage for the negotiated streams if it is not a temporary
2462 asoc->ssnmap = sctp_ssnmap_new(asoc->c.sinit_max_instreams,
2463 asoc->c.sinit_num_ostreams, gfp);
2467 error = sctp_assoc_set_id(asoc, gfp);
2472 /* ADDIP Section 4.1 ASCONF Chunk Procedures
2474 * When an endpoint has an ASCONF signaled change to be sent to the
2475 * remote endpoint it should do the following:
2477 * A2) A serial number should be assigned to the Chunk. The serial
2478 * number should be a monotonically increasing number. All serial
2479 * numbers are defined to be initialized at the start of the
2480 * association to the same value as the Initial TSN.
2482 asoc->peer.addip_serial = asoc->peer.i.initial_tsn - 1;
2486 /* Release the transport structures. */
2487 list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
2488 transport = list_entry(pos, struct sctp_transport, transports);
2489 if (transport->state != SCTP_ACTIVE)
2490 sctp_assoc_rm_peer(asoc, transport);
2498 /* Update asoc with the option described in param.
2500 * RFC2960 3.3.2.1 Optional/Variable Length Parameters in INIT
2502 * asoc is the association to update.
2503 * param is the variable length parameter to use for update.
2504 * cid tells us if this is an INIT, INIT ACK or COOKIE ECHO.
2505 * If the current packet is an INIT we want to minimize the amount of
2506 * work we do. In particular, we should not build transport
2507 * structures for the addresses.
2509 static int sctp_process_param(struct sctp_association *asoc,
2510 union sctp_params param,
2511 const union sctp_addr *peer_addr,
2514 struct net *net = sock_net(asoc->base.sk);
2515 union sctp_addr addr;
2522 union sctp_addr_param *addr_param;
2523 struct sctp_transport *t;
2524 struct sctp_endpoint *ep = asoc->ep;
2526 /* We maintain all INIT parameters in network byte order all the
2527 * time. This allows us to not worry about whether the parameters
2528 * came from a fresh INIT, and INIT ACK, or were stored in a cookie.
2530 switch (param.p->type) {
2531 case SCTP_PARAM_IPV6_ADDRESS:
2532 if (PF_INET6 != asoc->base.sk->sk_family)
2536 case SCTP_PARAM_IPV4_ADDRESS:
2537 /* v4 addresses are not allowed on v6-only socket */
2538 if (ipv6_only_sock(asoc->base.sk))
2541 af = sctp_get_af_specific(param_type2af(param.p->type));
2542 af->from_addr_param(&addr, param.addr, htons(asoc->peer.port), 0);
2543 scope = sctp_scope(peer_addr);
2544 if (sctp_in_scope(net, &addr, scope))
2545 if (!sctp_assoc_add_peer(asoc, &addr, gfp, SCTP_UNCONFIRMED))
2549 case SCTP_PARAM_COOKIE_PRESERVATIVE:
2550 if (!net->sctp.cookie_preserve_enable)
2553 stale = ntohl(param.life->lifespan_increment);
2555 /* Suggested Cookie Life span increment's unit is msec,
2558 asoc->cookie_life = ktime_add_ms(asoc->cookie_life, stale);
2561 case SCTP_PARAM_HOST_NAME_ADDRESS:
2562 pr_debug("%s: unimplemented SCTP_HOST_NAME_ADDRESS\n", __func__);
2565 case SCTP_PARAM_SUPPORTED_ADDRESS_TYPES:
2566 /* Turn off the default values first so we'll know which
2567 * ones are really set by the peer.
2569 asoc->peer.ipv4_address = 0;
2570 asoc->peer.ipv6_address = 0;
2572 /* Assume that peer supports the address family
2573 * by which it sends a packet.
2575 if (peer_addr->sa.sa_family == AF_INET6)
2576 asoc->peer.ipv6_address = 1;
2577 else if (peer_addr->sa.sa_family == AF_INET)
2578 asoc->peer.ipv4_address = 1;
2580 /* Cycle through address types; avoid divide by 0. */
2581 sat = ntohs(param.p->length) - sizeof(sctp_paramhdr_t);
2583 sat /= sizeof(__u16);
2585 for (i = 0; i < sat; ++i) {
2586 switch (param.sat->types[i]) {
2587 case SCTP_PARAM_IPV4_ADDRESS:
2588 asoc->peer.ipv4_address = 1;
2591 case SCTP_PARAM_IPV6_ADDRESS:
2592 if (PF_INET6 == asoc->base.sk->sk_family)
2593 asoc->peer.ipv6_address = 1;
2596 case SCTP_PARAM_HOST_NAME_ADDRESS:
2597 asoc->peer.hostname_address = 1;
2600 default: /* Just ignore anything else. */
2606 case SCTP_PARAM_STATE_COOKIE:
2607 asoc->peer.cookie_len =
2608 ntohs(param.p->length) - sizeof(sctp_paramhdr_t);
2609 asoc->peer.cookie = param.cookie->body;
2612 case SCTP_PARAM_HEARTBEAT_INFO:
2613 /* Would be odd to receive, but it causes no problems. */
2616 case SCTP_PARAM_UNRECOGNIZED_PARAMETERS:
2617 /* Rejected during verify stage. */
2620 case SCTP_PARAM_ECN_CAPABLE:
2621 asoc->peer.ecn_capable = 1;
2624 case SCTP_PARAM_ADAPTATION_LAYER_IND:
2625 asoc->peer.adaptation_ind = ntohl(param.aind->adaptation_ind);
2628 case SCTP_PARAM_SET_PRIMARY:
2629 if (!net->sctp.addip_enable)
2632 addr_param = param.v + sizeof(sctp_addip_param_t);
2634 af = sctp_get_af_specific(param_type2af(addr_param->p.type));
2638 af->from_addr_param(&addr, addr_param,
2639 htons(asoc->peer.port), 0);
2641 /* if the address is invalid, we can't process it.
2642 * XXX: see spec for what to do.
2644 if (!af->addr_valid(&addr, NULL, NULL))
2647 t = sctp_assoc_lookup_paddr(asoc, &addr);
2651 sctp_assoc_set_primary(asoc, t);
2654 case SCTP_PARAM_SUPPORTED_EXT:
2655 sctp_process_ext_param(asoc, param);
2658 case SCTP_PARAM_FWD_TSN_SUPPORT:
2659 if (asoc->prsctp_enable) {
2660 asoc->peer.prsctp_capable = 1;
2666 case SCTP_PARAM_RANDOM:
2667 if (!ep->auth_enable)
2670 /* Save peer's random parameter */
2671 asoc->peer.peer_random = kmemdup(param.p,
2672 ntohs(param.p->length), gfp);
2673 if (!asoc->peer.peer_random) {
2679 case SCTP_PARAM_HMAC_ALGO:
2680 if (!ep->auth_enable)
2683 /* Save peer's HMAC list */
2684 asoc->peer.peer_hmacs = kmemdup(param.p,
2685 ntohs(param.p->length), gfp);
2686 if (!asoc->peer.peer_hmacs) {
2691 /* Set the default HMAC the peer requested*/
2692 sctp_auth_asoc_set_default_hmac(asoc, param.hmac_algo);
2695 case SCTP_PARAM_CHUNKS:
2696 if (!ep->auth_enable)
2699 asoc->peer.peer_chunks = kmemdup(param.p,
2700 ntohs(param.p->length), gfp);
2701 if (!asoc->peer.peer_chunks)
2706 /* Any unrecognized parameters should have been caught
2707 * and handled by sctp_verify_param() which should be
2708 * called prior to this routine. Simply log the error
2711 pr_debug("%s: ignoring param:%d for association:%p.\n",
2712 __func__, ntohs(param.p->type), asoc);
2719 /* Select a new verification tag. */
2720 __u32 sctp_generate_tag(const struct sctp_endpoint *ep)
2722 /* I believe that this random number generator complies with RFC1750.
2723 * A tag of 0 is reserved for special cases (e.g. INIT).
2728 get_random_bytes(&x, sizeof(__u32));
2734 /* Select an initial TSN to send during startup. */
2735 __u32 sctp_generate_tsn(const struct sctp_endpoint *ep)
2739 get_random_bytes(&retval, sizeof(__u32));
2744 * ADDIP 3.1.1 Address Configuration Change Chunk (ASCONF)
2746 * 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
2747 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2748 * | Type = 0xC1 | Chunk Flags | Chunk Length |
2749 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2751 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2752 * | Address Parameter |
2753 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2754 * | ASCONF Parameter #1 |
2755 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2759 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2760 * | ASCONF Parameter #N |
2761 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2763 * Address Parameter and other parameter will not be wrapped in this function
2765 static struct sctp_chunk *sctp_make_asconf(struct sctp_association *asoc,
2766 union sctp_addr *addr,
2769 sctp_addiphdr_t asconf;
2770 struct sctp_chunk *retval;
2771 int length = sizeof(asconf) + vparam_len;
2772 union sctp_addr_param addrparam;
2774 struct sctp_af *af = sctp_get_af_specific(addr->v4.sin_family);
2776 addrlen = af->to_addr_param(addr, &addrparam);
2781 /* Create the chunk. */
2782 retval = sctp_make_control(asoc, SCTP_CID_ASCONF, 0, length,
2787 asconf.serial = htonl(asoc->addip_serial++);
2789 retval->subh.addip_hdr =
2790 sctp_addto_chunk(retval, sizeof(asconf), &asconf);
2791 retval->param_hdr.v =
2792 sctp_addto_chunk(retval, addrlen, &addrparam);
2798 * 3.2.1 Add IP Address
2800 * 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
2801 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2802 * | Type = 0xC001 | Length = Variable |
2803 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2804 * | ASCONF-Request Correlation ID |
2805 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2806 * | Address Parameter |
2807 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2809 * 3.2.2 Delete IP Address
2811 * 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
2812 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2813 * | Type = 0xC002 | Length = Variable |
2814 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2815 * | ASCONF-Request Correlation ID |
2816 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2817 * | Address Parameter |
2818 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2821 struct sctp_chunk *sctp_make_asconf_update_ip(struct sctp_association *asoc,
2822 union sctp_addr *laddr,
2823 struct sockaddr *addrs,
2827 sctp_addip_param_t param;
2828 struct sctp_chunk *retval;
2829 union sctp_addr_param addr_param;
2830 union sctp_addr *addr;
2833 int paramlen = sizeof(param);
2834 int addr_param_len = 0;
2839 /* Get total length of all the address parameters. */
2841 for (i = 0; i < addrcnt; i++) {
2843 af = sctp_get_af_specific(addr->v4.sin_family);
2844 addr_param_len = af->to_addr_param(addr, &addr_param);
2846 totallen += paramlen;
2847 totallen += addr_param_len;
2849 addr_buf += af->sockaddr_len;
2850 if (asoc->asconf_addr_del_pending && !del_pickup) {
2851 /* reuse the parameter length from the same scope one */
2852 totallen += paramlen;
2853 totallen += addr_param_len;
2856 pr_debug("%s: picked same-scope del_pending addr, "
2857 "totallen for all addresses is %d\n",
2858 __func__, totallen);
2862 /* Create an asconf chunk with the required length. */
2863 retval = sctp_make_asconf(asoc, laddr, totallen);
2867 /* Add the address parameters to the asconf chunk. */
2869 for (i = 0; i < addrcnt; i++) {
2871 af = sctp_get_af_specific(addr->v4.sin_family);
2872 addr_param_len = af->to_addr_param(addr, &addr_param);
2873 param.param_hdr.type = flags;
2874 param.param_hdr.length = htons(paramlen + addr_param_len);
2877 sctp_addto_chunk(retval, paramlen, ¶m);
2878 sctp_addto_chunk(retval, addr_param_len, &addr_param);
2880 addr_buf += af->sockaddr_len;
2882 if (flags == SCTP_PARAM_ADD_IP && del_pickup) {
2883 addr = asoc->asconf_addr_del_pending;
2884 af = sctp_get_af_specific(addr->v4.sin_family);
2885 addr_param_len = af->to_addr_param(addr, &addr_param);
2886 param.param_hdr.type = SCTP_PARAM_DEL_IP;
2887 param.param_hdr.length = htons(paramlen + addr_param_len);
2890 sctp_addto_chunk(retval, paramlen, ¶m);
2891 sctp_addto_chunk(retval, addr_param_len, &addr_param);
2897 * 3.2.4 Set Primary IP Address
2899 * 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
2900 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2901 * | Type =0xC004 | Length = Variable |
2902 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2903 * | ASCONF-Request Correlation ID |
2904 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2905 * | Address Parameter |
2906 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2908 * Create an ASCONF chunk with Set Primary IP address parameter.
2910 struct sctp_chunk *sctp_make_asconf_set_prim(struct sctp_association *asoc,
2911 union sctp_addr *addr)
2913 sctp_addip_param_t param;
2914 struct sctp_chunk *retval;
2915 int len = sizeof(param);
2916 union sctp_addr_param addrparam;
2918 struct sctp_af *af = sctp_get_af_specific(addr->v4.sin_family);
2920 addrlen = af->to_addr_param(addr, &addrparam);
2925 /* Create the chunk and make asconf header. */
2926 retval = sctp_make_asconf(asoc, addr, len);
2930 param.param_hdr.type = SCTP_PARAM_SET_PRIMARY;
2931 param.param_hdr.length = htons(len);
2934 sctp_addto_chunk(retval, sizeof(param), ¶m);
2935 sctp_addto_chunk(retval, addrlen, &addrparam);
2940 /* ADDIP 3.1.2 Address Configuration Acknowledgement Chunk (ASCONF-ACK)
2942 * 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
2943 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2944 * | Type = 0x80 | Chunk Flags | Chunk Length |
2945 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2947 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2948 * | ASCONF Parameter Response#1 |
2949 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2953 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2954 * | ASCONF Parameter Response#N |
2955 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2957 * Create an ASCONF_ACK chunk with enough space for the parameter responses.
2959 static struct sctp_chunk *sctp_make_asconf_ack(const struct sctp_association *asoc,
2960 __u32 serial, int vparam_len)
2962 sctp_addiphdr_t asconf;
2963 struct sctp_chunk *retval;
2964 int length = sizeof(asconf) + vparam_len;
2966 /* Create the chunk. */
2967 retval = sctp_make_control(asoc, SCTP_CID_ASCONF_ACK, 0, length,
2972 asconf.serial = htonl(serial);
2974 retval->subh.addip_hdr =
2975 sctp_addto_chunk(retval, sizeof(asconf), &asconf);
2980 /* Add response parameters to an ASCONF_ACK chunk. */
2981 static void sctp_add_asconf_response(struct sctp_chunk *chunk, __be32 crr_id,
2982 __be16 err_code, sctp_addip_param_t *asconf_param)
2984 sctp_addip_param_t ack_param;
2985 sctp_errhdr_t err_param;
2986 int asconf_param_len = 0;
2987 int err_param_len = 0;
2988 __be16 response_type;
2990 if (SCTP_ERROR_NO_ERROR == err_code) {
2991 response_type = SCTP_PARAM_SUCCESS_REPORT;
2993 response_type = SCTP_PARAM_ERR_CAUSE;
2994 err_param_len = sizeof(err_param);
2997 ntohs(asconf_param->param_hdr.length);
3000 /* Add Success Indication or Error Cause Indication parameter. */
3001 ack_param.param_hdr.type = response_type;
3002 ack_param.param_hdr.length = htons(sizeof(ack_param) +
3005 ack_param.crr_id = crr_id;
3006 sctp_addto_chunk(chunk, sizeof(ack_param), &ack_param);
3008 if (SCTP_ERROR_NO_ERROR == err_code)
3011 /* Add Error Cause parameter. */
3012 err_param.cause = err_code;
3013 err_param.length = htons(err_param_len + asconf_param_len);
3014 sctp_addto_chunk(chunk, err_param_len, &err_param);
3016 /* Add the failed TLV copied from ASCONF chunk. */
3018 sctp_addto_chunk(chunk, asconf_param_len, asconf_param);
3021 /* Process a asconf parameter. */
3022 static __be16 sctp_process_asconf_param(struct sctp_association *asoc,
3023 struct sctp_chunk *asconf,
3024 sctp_addip_param_t *asconf_param)
3026 struct sctp_transport *peer;
3028 union sctp_addr addr;
3029 union sctp_addr_param *addr_param;
3031 addr_param = (void *)asconf_param + sizeof(sctp_addip_param_t);
3033 if (asconf_param->param_hdr.type != SCTP_PARAM_ADD_IP &&
3034 asconf_param->param_hdr.type != SCTP_PARAM_DEL_IP &&
3035 asconf_param->param_hdr.type != SCTP_PARAM_SET_PRIMARY)
3036 return SCTP_ERROR_UNKNOWN_PARAM;
3038 switch (addr_param->p.type) {
3039 case SCTP_PARAM_IPV6_ADDRESS:
3040 if (!asoc->peer.ipv6_address)
3041 return SCTP_ERROR_DNS_FAILED;
3043 case SCTP_PARAM_IPV4_ADDRESS:
3044 if (!asoc->peer.ipv4_address)
3045 return SCTP_ERROR_DNS_FAILED;
3048 return SCTP_ERROR_DNS_FAILED;
3051 af = sctp_get_af_specific(param_type2af(addr_param->p.type));
3053 return SCTP_ERROR_DNS_FAILED;
3055 af->from_addr_param(&addr, addr_param, htons(asoc->peer.port), 0);
3057 /* ADDIP 4.2.1 This parameter MUST NOT contain a broadcast
3058 * or multicast address.
3059 * (note: wildcard is permitted and requires special handling so
3060 * make sure we check for that)
3062 if (!af->is_any(&addr) && !af->addr_valid(&addr, NULL, asconf->skb))
3063 return SCTP_ERROR_DNS_FAILED;
3065 switch (asconf_param->param_hdr.type) {
3066 case SCTP_PARAM_ADD_IP:
3068 * If the address 0.0.0.0 or ::0 is provided, the source
3069 * address of the packet MUST be added.
3071 if (af->is_any(&addr))
3072 memcpy(&addr, &asconf->source, sizeof(addr));
3074 /* ADDIP 4.3 D9) If an endpoint receives an ADD IP address
3075 * request and does not have the local resources to add this
3076 * new address to the association, it MUST return an Error
3077 * Cause TLV set to the new error code 'Operation Refused
3078 * Due to Resource Shortage'.
3081 peer = sctp_assoc_add_peer(asoc, &addr, GFP_ATOMIC, SCTP_UNCONFIRMED);
3083 return SCTP_ERROR_RSRC_LOW;
3085 /* Start the heartbeat timer. */
3086 sctp_transport_reset_hb_timer(peer);
3087 asoc->new_transport = peer;
3089 case SCTP_PARAM_DEL_IP:
3090 /* ADDIP 4.3 D7) If a request is received to delete the
3091 * last remaining IP address of a peer endpoint, the receiver
3092 * MUST send an Error Cause TLV with the error cause set to the
3093 * new error code 'Request to Delete Last Remaining IP Address'.
3095 if (asoc->peer.transport_count == 1)
3096 return SCTP_ERROR_DEL_LAST_IP;
3098 /* ADDIP 4.3 D8) If a request is received to delete an IP
3099 * address which is also the source address of the IP packet
3100 * which contained the ASCONF chunk, the receiver MUST reject
3101 * this request. To reject the request the receiver MUST send
3102 * an Error Cause TLV set to the new error code 'Request to
3103 * Delete Source IP Address'
3105 if (sctp_cmp_addr_exact(&asconf->source, &addr))
3106 return SCTP_ERROR_DEL_SRC_IP;
3109 * If the address 0.0.0.0 or ::0 is provided, all
3110 * addresses of the peer except the source address of the
3111 * packet MUST be deleted.
3113 if (af->is_any(&addr)) {
3114 sctp_assoc_set_primary(asoc, asconf->transport);
3115 sctp_assoc_del_nonprimary_peers(asoc,
3117 return SCTP_ERROR_NO_ERROR;
3120 /* If the address is not part of the association, the
3121 * ASCONF-ACK with Error Cause Indication Parameter
3122 * which including cause of Unresolvable Address should
3125 peer = sctp_assoc_lookup_paddr(asoc, &addr);
3127 return SCTP_ERROR_DNS_FAILED;
3129 sctp_assoc_rm_peer(asoc, peer);
3131 case SCTP_PARAM_SET_PRIMARY:
3132 /* ADDIP Section 4.2.4
3133 * If the address 0.0.0.0 or ::0 is provided, the receiver
3134 * MAY mark the source address of the packet as its
3137 if (af->is_any(&addr))
3138 memcpy(&addr.v4, sctp_source(asconf), sizeof(addr));
3140 peer = sctp_assoc_lookup_paddr(asoc, &addr);
3142 return SCTP_ERROR_DNS_FAILED;
3144 sctp_assoc_set_primary(asoc, peer);
3148 return SCTP_ERROR_NO_ERROR;
3151 /* Verify the ASCONF packet before we process it. */
3152 bool sctp_verify_asconf(const struct sctp_association *asoc,
3153 struct sctp_chunk *chunk, bool addr_param_needed,
3154 struct sctp_paramhdr **errp)
3156 sctp_addip_chunk_t *addip = (sctp_addip_chunk_t *) chunk->chunk_hdr;
3157 union sctp_params param;
3158 bool addr_param_seen = false;
3160 sctp_walk_params(param, addip, addip_hdr.params) {
3161 size_t length = ntohs(param.p->length);
3164 switch (param.p->type) {
3165 case SCTP_PARAM_ERR_CAUSE:
3167 case SCTP_PARAM_IPV4_ADDRESS:
3168 if (length != sizeof(sctp_ipv4addr_param_t))
3170 /* ensure there is only one addr param and it's in the
3171 * beginning of addip_hdr params, or we reject it.
3173 if (param.v != addip->addip_hdr.params)
3175 addr_param_seen = true;
3177 case SCTP_PARAM_IPV6_ADDRESS:
3178 if (length != sizeof(sctp_ipv6addr_param_t))
3180 if (param.v != addip->addip_hdr.params)
3182 addr_param_seen = true;
3184 case SCTP_PARAM_ADD_IP:
3185 case SCTP_PARAM_DEL_IP:
3186 case SCTP_PARAM_SET_PRIMARY:
3187 /* In ASCONF chunks, these need to be first. */
3188 if (addr_param_needed && !addr_param_seen)
3190 length = ntohs(param.addip->param_hdr.length);
3191 if (length < sizeof(sctp_addip_param_t) +
3192 sizeof(sctp_paramhdr_t))
3195 case SCTP_PARAM_SUCCESS_REPORT:
3196 case SCTP_PARAM_ADAPTATION_LAYER_IND:
3197 if (length != sizeof(sctp_addip_param_t))
3201 /* This is unkown to us, reject! */
3206 /* Remaining sanity checks. */
3207 if (addr_param_needed && !addr_param_seen)
3209 if (!addr_param_needed && addr_param_seen)
3211 if (param.v != chunk->chunk_end)
3217 /* Process an incoming ASCONF chunk with the next expected serial no. and
3218 * return an ASCONF_ACK chunk to be sent in response.
3220 struct sctp_chunk *sctp_process_asconf(struct sctp_association *asoc,
3221 struct sctp_chunk *asconf)
3223 sctp_addip_chunk_t *addip = (sctp_addip_chunk_t *) asconf->chunk_hdr;
3224 bool all_param_pass = true;
3225 union sctp_params param;
3226 sctp_addiphdr_t *hdr;
3227 union sctp_addr_param *addr_param;
3228 sctp_addip_param_t *asconf_param;
3229 struct sctp_chunk *asconf_ack;
3235 chunk_len = ntohs(asconf->chunk_hdr->length) - sizeof(sctp_chunkhdr_t);
3236 hdr = (sctp_addiphdr_t *)asconf->skb->data;
3237 serial = ntohl(hdr->serial);
3239 /* Skip the addiphdr and store a pointer to address parameter. */
3240 length = sizeof(sctp_addiphdr_t);
3241 addr_param = (union sctp_addr_param *)(asconf->skb->data + length);
3242 chunk_len -= length;
3244 /* Skip the address parameter and store a pointer to the first
3247 length = ntohs(addr_param->p.length);
3248 asconf_param = (void *)addr_param + length;
3249 chunk_len -= length;
3251 /* create an ASCONF_ACK chunk.
3252 * Based on the definitions of parameters, we know that the size of
3253 * ASCONF_ACK parameters are less than or equal to the fourfold of ASCONF
3256 asconf_ack = sctp_make_asconf_ack(asoc, serial, chunk_len * 4);
3260 /* Process the TLVs contained within the ASCONF chunk. */
3261 sctp_walk_params(param, addip, addip_hdr.params) {
3262 /* Skip preceeding address parameters. */
3263 if (param.p->type == SCTP_PARAM_IPV4_ADDRESS ||
3264 param.p->type == SCTP_PARAM_IPV6_ADDRESS)
3267 err_code = sctp_process_asconf_param(asoc, asconf,
3270 * If an error response is received for a TLV parameter,
3271 * all TLVs with no response before the failed TLV are
3272 * considered successful if not reported. All TLVs after
3273 * the failed response are considered unsuccessful unless
3274 * a specific success indication is present for the parameter.
3276 if (err_code != SCTP_ERROR_NO_ERROR)
3277 all_param_pass = false;
3278 if (!all_param_pass)
3279 sctp_add_asconf_response(asconf_ack, param.addip->crr_id,
3280 err_code, param.addip);
3282 /* ADDIP 4.3 D11) When an endpoint receiving an ASCONF to add
3283 * an IP address sends an 'Out of Resource' in its response, it
3284 * MUST also fail any subsequent add or delete requests bundled
3287 if (err_code == SCTP_ERROR_RSRC_LOW)
3291 asoc->peer.addip_serial++;
3293 /* If we are sending a new ASCONF_ACK hold a reference to it in assoc
3294 * after freeing the reference to old asconf ack if any.
3297 sctp_chunk_hold(asconf_ack);
3298 list_add_tail(&asconf_ack->transmitted_list,
3299 &asoc->asconf_ack_list);
3305 /* Process a asconf parameter that is successfully acked. */
3306 static void sctp_asconf_param_success(struct sctp_association *asoc,
3307 sctp_addip_param_t *asconf_param)
3310 union sctp_addr addr;
3311 struct sctp_bind_addr *bp = &asoc->base.bind_addr;
3312 union sctp_addr_param *addr_param;
3313 struct sctp_transport *transport;
3314 struct sctp_sockaddr_entry *saddr;
3316 addr_param = (void *)asconf_param + sizeof(sctp_addip_param_t);
3318 /* We have checked the packet before, so we do not check again. */
3319 af = sctp_get_af_specific(param_type2af(addr_param->p.type));
3320 af->from_addr_param(&addr, addr_param, htons(bp->port), 0);
3322 switch (asconf_param->param_hdr.type) {
3323 case SCTP_PARAM_ADD_IP:
3324 /* This is always done in BH context with a socket lock
3325 * held, so the list can not change.
3328 list_for_each_entry(saddr, &bp->address_list, list) {
3329 if (sctp_cmp_addr_exact(&saddr->a, &addr))
3330 saddr->state = SCTP_ADDR_SRC;
3333 list_for_each_entry(transport, &asoc->peer.transport_addr_list,
3335 dst_release(transport->dst);
3336 transport->dst = NULL;
3339 case SCTP_PARAM_DEL_IP:
3341 sctp_del_bind_addr(bp, &addr);
3342 if (asoc->asconf_addr_del_pending != NULL &&
3343 sctp_cmp_addr_exact(asoc->asconf_addr_del_pending, &addr)) {
3344 kfree(asoc->asconf_addr_del_pending);
3345 asoc->asconf_addr_del_pending = NULL;
3348 list_for_each_entry(transport, &asoc->peer.transport_addr_list,
3350 dst_release(transport->dst);
3351 transport->dst = NULL;
3359 /* Get the corresponding ASCONF response error code from the ASCONF_ACK chunk
3360 * for the given asconf parameter. If there is no response for this parameter,
3361 * return the error code based on the third argument 'no_err'.
3363 * A7) If an error response is received for a TLV parameter, all TLVs with no
3364 * response before the failed TLV are considered successful if not reported.
3365 * All TLVs after the failed response are considered unsuccessful unless a
3366 * specific success indication is present for the parameter.
3368 static __be16 sctp_get_asconf_response(struct sctp_chunk *asconf_ack,
3369 sctp_addip_param_t *asconf_param,
3372 sctp_addip_param_t *asconf_ack_param;
3373 sctp_errhdr_t *err_param;
3379 err_code = SCTP_ERROR_NO_ERROR;
3381 err_code = SCTP_ERROR_REQ_REFUSED;
3383 asconf_ack_len = ntohs(asconf_ack->chunk_hdr->length) -
3384 sizeof(sctp_chunkhdr_t);
3386 /* Skip the addiphdr from the asconf_ack chunk and store a pointer to
3387 * the first asconf_ack parameter.
3389 length = sizeof(sctp_addiphdr_t);
3390 asconf_ack_param = (sctp_addip_param_t *)(asconf_ack->skb->data +
3392 asconf_ack_len -= length;
3394 while (asconf_ack_len > 0) {
3395 if (asconf_ack_param->crr_id == asconf_param->crr_id) {
3396 switch (asconf_ack_param->param_hdr.type) {
3397 case SCTP_PARAM_SUCCESS_REPORT:
3398 return SCTP_ERROR_NO_ERROR;
3399 case SCTP_PARAM_ERR_CAUSE:
3400 length = sizeof(sctp_addip_param_t);
3401 err_param = (void *)asconf_ack_param + length;
3402 asconf_ack_len -= length;
3403 if (asconf_ack_len > 0)
3404 return err_param->cause;
3406 return SCTP_ERROR_INV_PARAM;
3409 return SCTP_ERROR_INV_PARAM;
3413 length = ntohs(asconf_ack_param->param_hdr.length);
3414 asconf_ack_param = (void *)asconf_ack_param + length;
3415 asconf_ack_len -= length;
3421 /* Process an incoming ASCONF_ACK chunk against the cached last ASCONF chunk. */
3422 int sctp_process_asconf_ack(struct sctp_association *asoc,
3423 struct sctp_chunk *asconf_ack)
3425 struct sctp_chunk *asconf = asoc->addip_last_asconf;
3426 union sctp_addr_param *addr_param;
3427 sctp_addip_param_t *asconf_param;
3429 int asconf_len = asconf->skb->len;
3430 int all_param_pass = 0;
3433 __be16 err_code = SCTP_ERROR_NO_ERROR;
3435 /* Skip the chunkhdr and addiphdr from the last asconf sent and store
3436 * a pointer to address parameter.
3438 length = sizeof(sctp_addip_chunk_t);
3439 addr_param = (union sctp_addr_param *)(asconf->skb->data + length);
3440 asconf_len -= length;
3442 /* Skip the address parameter in the last asconf sent and store a
3443 * pointer to the first asconf parameter.
3445 length = ntohs(addr_param->p.length);
3446 asconf_param = (void *)addr_param + length;
3447 asconf_len -= length;
3450 * A8) If there is no response(s) to specific TLV parameter(s), and no
3451 * failures are indicated, then all request(s) are considered
3454 if (asconf_ack->skb->len == sizeof(sctp_addiphdr_t))
3457 /* Process the TLVs contained in the last sent ASCONF chunk. */
3458 while (asconf_len > 0) {
3460 err_code = SCTP_ERROR_NO_ERROR;
3462 err_code = sctp_get_asconf_response(asconf_ack,
3465 if (no_err && (SCTP_ERROR_NO_ERROR != err_code))
3470 case SCTP_ERROR_NO_ERROR:
3471 sctp_asconf_param_success(asoc, asconf_param);
3474 case SCTP_ERROR_RSRC_LOW:
3478 case SCTP_ERROR_UNKNOWN_PARAM:
3479 /* Disable sending this type of asconf parameter in
3482 asoc->peer.addip_disabled_mask |=
3483 asconf_param->param_hdr.type;
3486 case SCTP_ERROR_REQ_REFUSED:
3487 case SCTP_ERROR_DEL_LAST_IP:
3488 case SCTP_ERROR_DEL_SRC_IP:
3493 /* Skip the processed asconf parameter and move to the next
3496 length = ntohs(asconf_param->param_hdr.length);
3497 asconf_param = (void *)asconf_param + length;
3498 asconf_len -= length;
3501 if (no_err && asoc->src_out_of_asoc_ok) {
3502 asoc->src_out_of_asoc_ok = 0;
3503 sctp_transport_immediate_rtx(asoc->peer.primary_path);
3506 /* Free the cached last sent asconf chunk. */
3507 list_del_init(&asconf->transmitted_list);
3508 sctp_chunk_free(asconf);
3509 asoc->addip_last_asconf = NULL;
3514 /* Make a FWD TSN chunk. */
3515 struct sctp_chunk *sctp_make_fwdtsn(const struct sctp_association *asoc,
3516 __u32 new_cum_tsn, size_t nstreams,
3517 struct sctp_fwdtsn_skip *skiplist)
3519 struct sctp_chunk *retval = NULL;
3520 struct sctp_fwdtsn_hdr ftsn_hdr;
3521 struct sctp_fwdtsn_skip skip;
3525 hint = (nstreams + 1) * sizeof(__u32);
3527 retval = sctp_make_control(asoc, SCTP_CID_FWD_TSN, 0, hint, GFP_ATOMIC);
3532 ftsn_hdr.new_cum_tsn = htonl(new_cum_tsn);
3533 retval->subh.fwdtsn_hdr =
3534 sctp_addto_chunk(retval, sizeof(ftsn_hdr), &ftsn_hdr);
3536 for (i = 0; i < nstreams; i++) {
3537 skip.stream = skiplist[i].stream;
3538 skip.ssn = skiplist[i].ssn;
3539 sctp_addto_chunk(retval, sizeof(skip), &skip);