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)
114 af = sctp_get_af_specific(ipver2af(ip_hdr(chunk->skb)->version));
116 iif = af->skb_iif(chunk->skb);
121 /* RFC 2960 3.3.2 Initiation (INIT) (1)
123 * Note 2: The ECN capable field is reserved for future use of
124 * Explicit Congestion Notification.
126 static const struct sctp_paramhdr ecap_param = {
127 SCTP_PARAM_ECN_CAPABLE,
128 cpu_to_be16(sizeof(struct sctp_paramhdr)),
130 static const struct sctp_paramhdr prsctp_param = {
131 SCTP_PARAM_FWD_TSN_SUPPORT,
132 cpu_to_be16(sizeof(struct sctp_paramhdr)),
135 /* A helper to initialize an op error inside a
136 * provided chunk, as most cause codes will be embedded inside an
139 void sctp_init_cause(struct sctp_chunk *chunk, __be16 cause_code,
145 /* Cause code constants are now defined in network order. */
146 err.cause = cause_code;
147 len = sizeof(sctp_errhdr_t) + paylen;
148 err.length = htons(len);
149 chunk->subh.err_hdr = sctp_addto_chunk(chunk, sizeof(sctp_errhdr_t), &err);
152 /* A helper to initialize an op error inside a
153 * provided chunk, as most cause codes will be embedded inside an
154 * abort chunk. Differs from sctp_init_cause in that it won't oops
155 * if there isn't enough space in the op error chunk
157 static int sctp_init_cause_fixed(struct sctp_chunk *chunk, __be16 cause_code,
163 /* Cause code constants are now defined in network order. */
164 err.cause = cause_code;
165 len = sizeof(sctp_errhdr_t) + paylen;
166 err.length = htons(len);
168 if (skb_tailroom(chunk->skb) < len)
170 chunk->subh.err_hdr = sctp_addto_chunk_fixed(chunk,
171 sizeof(sctp_errhdr_t),
175 /* 3.3.2 Initiation (INIT) (1)
177 * This chunk is used to initiate a SCTP association between two
178 * endpoints. The format of the INIT chunk is shown below:
181 * 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
182 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
183 * | Type = 1 | Chunk Flags | Chunk Length |
184 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
186 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
187 * | Advertised Receiver Window Credit (a_rwnd) |
188 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
189 * | Number of Outbound Streams | Number of Inbound Streams |
190 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
192 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
194 * / Optional/Variable-Length Parameters /
196 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
199 * The INIT chunk contains the following parameters. Unless otherwise
200 * noted, each parameter MUST only be included once in the INIT chunk.
202 * Fixed Parameters Status
203 * ----------------------------------------------
204 * Initiate Tag Mandatory
205 * Advertised Receiver Window Credit Mandatory
206 * Number of Outbound Streams Mandatory
207 * Number of Inbound Streams Mandatory
208 * Initial TSN Mandatory
210 * Variable Parameters Status Type Value
211 * -------------------------------------------------------------
212 * IPv4 Address (Note 1) Optional 5
213 * IPv6 Address (Note 1) Optional 6
214 * Cookie Preservative Optional 9
215 * Reserved for ECN Capable (Note 2) Optional 32768 (0x8000)
216 * Host Name Address (Note 3) Optional 11
217 * Supported Address Types (Note 4) Optional 12
219 struct sctp_chunk *sctp_make_init(const struct sctp_association *asoc,
220 const struct sctp_bind_addr *bp,
221 gfp_t gfp, int vparam_len)
223 struct net *net = sock_net(asoc->base.sk);
224 struct sctp_endpoint *ep = asoc->ep;
226 union sctp_params addrs;
228 struct sctp_chunk *retval = NULL;
229 int num_types, addrs_len = 0;
230 struct sctp_sock *sp;
231 sctp_supported_addrs_param_t sat;
233 sctp_adaptation_ind_param_t aiparam;
234 sctp_supported_ext_param_t ext_param;
237 sctp_paramhdr_t *auth_chunks = NULL,
240 /* RFC 2960 3.3.2 Initiation (INIT) (1)
242 * Note 1: The INIT chunks can contain multiple addresses that
243 * can be IPv4 and/or IPv6 in any combination.
247 /* Convert the provided bind address list to raw format. */
248 addrs = sctp_bind_addrs_to_raw(bp, &addrs_len, gfp);
250 init.init_tag = htonl(asoc->c.my_vtag);
251 init.a_rwnd = htonl(asoc->rwnd);
252 init.num_outbound_streams = htons(asoc->c.sinit_num_ostreams);
253 init.num_inbound_streams = htons(asoc->c.sinit_max_instreams);
254 init.initial_tsn = htonl(asoc->c.initial_tsn);
256 /* How many address types are needed? */
257 sp = sctp_sk(asoc->base.sk);
258 num_types = sp->pf->supported_addrs(sp, types);
260 chunksize = sizeof(init) + addrs_len;
261 chunksize += WORD_ROUND(SCTP_SAT_LEN(num_types));
262 chunksize += sizeof(ecap_param);
264 if (asoc->prsctp_enable)
265 chunksize += sizeof(prsctp_param);
267 /* ADDIP: Section 4.2.7:
268 * An implementation supporting this extension [ADDIP] MUST list
269 * the ASCONF,the ASCONF-ACK, and the AUTH chunks in its INIT and
270 * INIT-ACK parameters.
272 if (net->sctp.addip_enable) {
273 extensions[num_ext] = SCTP_CID_ASCONF;
274 extensions[num_ext+1] = SCTP_CID_ASCONF_ACK;
278 if (sp->adaptation_ind)
279 chunksize += sizeof(aiparam);
281 chunksize += vparam_len;
283 /* Account for AUTH related parameters */
284 if (ep->auth_enable) {
285 /* Add random parameter length*/
286 chunksize += sizeof(asoc->c.auth_random);
288 /* Add HMACS parameter length if any were defined */
289 auth_hmacs = (sctp_paramhdr_t *)asoc->c.auth_hmacs;
290 if (auth_hmacs->length)
291 chunksize += WORD_ROUND(ntohs(auth_hmacs->length));
295 /* Add CHUNKS parameter length */
296 auth_chunks = (sctp_paramhdr_t *)asoc->c.auth_chunks;
297 if (auth_chunks->length)
298 chunksize += WORD_ROUND(ntohs(auth_chunks->length));
302 extensions[num_ext] = SCTP_CID_AUTH;
306 /* If we have any extensions to report, account for that */
308 chunksize += WORD_ROUND(sizeof(sctp_supported_ext_param_t) +
311 /* RFC 2960 3.3.2 Initiation (INIT) (1)
313 * Note 3: An INIT chunk MUST NOT contain more than one Host
314 * Name address parameter. Moreover, the sender of the INIT
315 * MUST NOT combine any other address types with the Host Name
316 * address in the INIT. The receiver of INIT MUST ignore any
317 * other address types if the Host Name address parameter is
318 * present in the received INIT chunk.
320 * PLEASE DO NOT FIXME [This version does not support Host Name.]
323 retval = sctp_make_control(asoc, SCTP_CID_INIT, 0, chunksize, gfp);
327 retval->subh.init_hdr =
328 sctp_addto_chunk(retval, sizeof(init), &init);
329 retval->param_hdr.v =
330 sctp_addto_chunk(retval, addrs_len, addrs.v);
332 /* RFC 2960 3.3.2 Initiation (INIT) (1)
334 * Note 4: This parameter, when present, specifies all the
335 * address types the sending endpoint can support. The absence
336 * of this parameter indicates that the sending endpoint can
337 * support any address type.
339 sat.param_hdr.type = SCTP_PARAM_SUPPORTED_ADDRESS_TYPES;
340 sat.param_hdr.length = htons(SCTP_SAT_LEN(num_types));
341 sctp_addto_chunk(retval, sizeof(sat), &sat);
342 sctp_addto_chunk(retval, num_types * sizeof(__u16), &types);
344 sctp_addto_chunk(retval, sizeof(ecap_param), &ecap_param);
346 /* Add the supported extensions parameter. Be nice and add this
347 * fist before addiding the parameters for the extensions themselves
350 ext_param.param_hdr.type = SCTP_PARAM_SUPPORTED_EXT;
351 ext_param.param_hdr.length =
352 htons(sizeof(sctp_supported_ext_param_t) + num_ext);
353 sctp_addto_chunk(retval, sizeof(sctp_supported_ext_param_t),
355 sctp_addto_param(retval, num_ext, extensions);
358 if (asoc->prsctp_enable)
359 sctp_addto_chunk(retval, sizeof(prsctp_param), &prsctp_param);
361 if (sp->adaptation_ind) {
362 aiparam.param_hdr.type = SCTP_PARAM_ADAPTATION_LAYER_IND;
363 aiparam.param_hdr.length = htons(sizeof(aiparam));
364 aiparam.adaptation_ind = htonl(sp->adaptation_ind);
365 sctp_addto_chunk(retval, sizeof(aiparam), &aiparam);
368 /* Add SCTP-AUTH chunks to the parameter list */
369 if (ep->auth_enable) {
370 sctp_addto_chunk(retval, sizeof(asoc->c.auth_random),
371 asoc->c.auth_random);
373 sctp_addto_chunk(retval, ntohs(auth_hmacs->length),
376 sctp_addto_chunk(retval, ntohs(auth_chunks->length),
384 struct sctp_chunk *sctp_make_init_ack(const struct sctp_association *asoc,
385 const struct sctp_chunk *chunk,
386 gfp_t gfp, int unkparam_len)
388 sctp_inithdr_t initack;
389 struct sctp_chunk *retval;
390 union sctp_params addrs;
391 struct sctp_sock *sp;
393 sctp_cookie_param_t *cookie;
396 sctp_adaptation_ind_param_t aiparam;
397 sctp_supported_ext_param_t ext_param;
400 sctp_paramhdr_t *auth_chunks = NULL,
406 /* Note: there may be no addresses to embed. */
407 addrs = sctp_bind_addrs_to_raw(&asoc->base.bind_addr, &addrs_len, gfp);
409 initack.init_tag = htonl(asoc->c.my_vtag);
410 initack.a_rwnd = htonl(asoc->rwnd);
411 initack.num_outbound_streams = htons(asoc->c.sinit_num_ostreams);
412 initack.num_inbound_streams = htons(asoc->c.sinit_max_instreams);
413 initack.initial_tsn = htonl(asoc->c.initial_tsn);
415 /* FIXME: We really ought to build the cookie right
416 * into the packet instead of allocating more fresh memory.
418 cookie = sctp_pack_cookie(asoc->ep, asoc, chunk, &cookie_len,
423 /* Calculate the total size of allocation, include the reserved
424 * space for reporting unknown parameters if it is specified.
426 sp = sctp_sk(asoc->base.sk);
427 chunksize = sizeof(initack) + addrs_len + cookie_len + unkparam_len;
429 /* Tell peer that we'll do ECN only if peer advertised such cap. */
430 if (asoc->peer.ecn_capable)
431 chunksize += sizeof(ecap_param);
433 if (asoc->peer.prsctp_capable)
434 chunksize += sizeof(prsctp_param);
436 if (asoc->peer.asconf_capable) {
437 extensions[num_ext] = SCTP_CID_ASCONF;
438 extensions[num_ext+1] = SCTP_CID_ASCONF_ACK;
442 if (sp->adaptation_ind)
443 chunksize += sizeof(aiparam);
445 if (asoc->peer.auth_capable) {
446 auth_random = (sctp_paramhdr_t *)asoc->c.auth_random;
447 chunksize += ntohs(auth_random->length);
449 auth_hmacs = (sctp_paramhdr_t *)asoc->c.auth_hmacs;
450 if (auth_hmacs->length)
451 chunksize += WORD_ROUND(ntohs(auth_hmacs->length));
455 auth_chunks = (sctp_paramhdr_t *)asoc->c.auth_chunks;
456 if (auth_chunks->length)
457 chunksize += WORD_ROUND(ntohs(auth_chunks->length));
461 extensions[num_ext] = SCTP_CID_AUTH;
466 chunksize += WORD_ROUND(sizeof(sctp_supported_ext_param_t) +
469 /* Now allocate and fill out the chunk. */
470 retval = sctp_make_control(asoc, SCTP_CID_INIT_ACK, 0, chunksize, gfp);
474 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
476 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
477 * HEARTBEAT ACK, * etc.) to the same destination transport
478 * address from which it received the DATA or control chunk
479 * to which it is replying.
481 * [INIT ACK back to where the INIT came from.]
483 retval->transport = chunk->transport;
485 retval->subh.init_hdr =
486 sctp_addto_chunk(retval, sizeof(initack), &initack);
487 retval->param_hdr.v = sctp_addto_chunk(retval, addrs_len, addrs.v);
488 sctp_addto_chunk(retval, cookie_len, cookie);
489 if (asoc->peer.ecn_capable)
490 sctp_addto_chunk(retval, sizeof(ecap_param), &ecap_param);
492 ext_param.param_hdr.type = SCTP_PARAM_SUPPORTED_EXT;
493 ext_param.param_hdr.length =
494 htons(sizeof(sctp_supported_ext_param_t) + num_ext);
495 sctp_addto_chunk(retval, sizeof(sctp_supported_ext_param_t),
497 sctp_addto_param(retval, num_ext, extensions);
499 if (asoc->peer.prsctp_capable)
500 sctp_addto_chunk(retval, sizeof(prsctp_param), &prsctp_param);
502 if (sp->adaptation_ind) {
503 aiparam.param_hdr.type = SCTP_PARAM_ADAPTATION_LAYER_IND;
504 aiparam.param_hdr.length = htons(sizeof(aiparam));
505 aiparam.adaptation_ind = htonl(sp->adaptation_ind);
506 sctp_addto_chunk(retval, sizeof(aiparam), &aiparam);
509 if (asoc->peer.auth_capable) {
510 sctp_addto_chunk(retval, ntohs(auth_random->length),
513 sctp_addto_chunk(retval, ntohs(auth_hmacs->length),
516 sctp_addto_chunk(retval, ntohs(auth_chunks->length),
520 /* We need to remove the const qualifier at this point. */
521 retval->asoc = (struct sctp_association *) asoc;
530 /* 3.3.11 Cookie Echo (COOKIE ECHO) (10):
532 * This chunk is used only during the initialization of an association.
533 * It is sent by the initiator of an association to its peer to complete
534 * the initialization process. This chunk MUST precede any DATA chunk
535 * sent within the association, but MAY be bundled with one or more DATA
536 * chunks in the same packet.
539 * 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
540 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
541 * | Type = 10 |Chunk Flags | Length |
542 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
545 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
549 * Set to zero on transmit and ignored on receipt.
551 * Length: 16 bits (unsigned integer)
553 * Set to the size of the chunk in bytes, including the 4 bytes of
554 * the chunk header and the size of the Cookie.
556 * Cookie: variable size
558 * This field must contain the exact cookie received in the
559 * State Cookie parameter from the previous INIT ACK.
561 * An implementation SHOULD make the cookie as small as possible
562 * to insure interoperability.
564 struct sctp_chunk *sctp_make_cookie_echo(const struct sctp_association *asoc,
565 const struct sctp_chunk *chunk)
567 struct sctp_chunk *retval;
571 cookie = asoc->peer.cookie;
572 cookie_len = asoc->peer.cookie_len;
574 /* Build a cookie echo chunk. */
575 retval = sctp_make_control(asoc, SCTP_CID_COOKIE_ECHO, 0,
576 cookie_len, GFP_ATOMIC);
579 retval->subh.cookie_hdr =
580 sctp_addto_chunk(retval, cookie_len, cookie);
582 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
584 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
585 * HEARTBEAT ACK, * etc.) to the same destination transport
586 * address from which it * received the DATA or control chunk
587 * to which it is replying.
589 * [COOKIE ECHO back to where the INIT ACK came from.]
592 retval->transport = chunk->transport;
598 /* 3.3.12 Cookie Acknowledgement (COOKIE ACK) (11):
600 * This chunk is used only during the initialization of an
601 * association. It is used to acknowledge the receipt of a COOKIE
602 * ECHO chunk. This chunk MUST precede any DATA or SACK chunk sent
603 * within the association, but MAY be bundled with one or more DATA
604 * chunks or SACK chunk in the same SCTP packet.
607 * 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
608 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
609 * | Type = 11 |Chunk Flags | Length = 4 |
610 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
612 * Chunk Flags: 8 bits
614 * Set to zero on transmit and ignored on receipt.
616 struct sctp_chunk *sctp_make_cookie_ack(const struct sctp_association *asoc,
617 const struct sctp_chunk *chunk)
619 struct sctp_chunk *retval;
621 retval = sctp_make_control(asoc, SCTP_CID_COOKIE_ACK, 0, 0, GFP_ATOMIC);
623 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
625 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
626 * HEARTBEAT ACK, * etc.) to the same destination transport
627 * address from which it * received the DATA or control chunk
628 * to which it is replying.
630 * [COOKIE ACK back to where the COOKIE ECHO came from.]
633 retval->transport = chunk->transport;
639 * Appendix A: Explicit Congestion Notification:
642 * RFC 2481 details a specific bit for a sender to send in the header of
643 * its next outbound TCP segment to indicate to its peer that it has
644 * reduced its congestion window. This is termed the CWR bit. For
645 * SCTP the same indication is made by including the CWR chunk.
646 * This chunk contains one data element, i.e. the TSN number that
647 * was sent in the ECNE chunk. This element represents the lowest
648 * TSN number in the datagram that was originally marked with the
652 * 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
653 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
654 * | Chunk Type=13 | Flags=00000000| Chunk Length = 8 |
655 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
656 * | Lowest TSN Number |
657 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
659 * Note: The CWR is considered a Control chunk.
661 struct sctp_chunk *sctp_make_cwr(const struct sctp_association *asoc,
662 const __u32 lowest_tsn,
663 const struct sctp_chunk *chunk)
665 struct sctp_chunk *retval;
668 cwr.lowest_tsn = htonl(lowest_tsn);
669 retval = sctp_make_control(asoc, SCTP_CID_ECN_CWR, 0,
670 sizeof(sctp_cwrhdr_t), GFP_ATOMIC);
675 retval->subh.ecn_cwr_hdr =
676 sctp_addto_chunk(retval, sizeof(cwr), &cwr);
678 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
680 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
681 * HEARTBEAT ACK, * etc.) to the same destination transport
682 * address from which it * received the DATA or control chunk
683 * to which it is replying.
685 * [Report a reduced congestion window back to where the ECNE
689 retval->transport = chunk->transport;
695 /* Make an ECNE chunk. This is a congestion experienced report. */
696 struct sctp_chunk *sctp_make_ecne(const struct sctp_association *asoc,
697 const __u32 lowest_tsn)
699 struct sctp_chunk *retval;
702 ecne.lowest_tsn = htonl(lowest_tsn);
703 retval = sctp_make_control(asoc, SCTP_CID_ECN_ECNE, 0,
704 sizeof(sctp_ecnehdr_t), GFP_ATOMIC);
707 retval->subh.ecne_hdr =
708 sctp_addto_chunk(retval, sizeof(ecne), &ecne);
714 static void sctp_set_prsctp_policy(struct sctp_chunk *chunk,
715 const struct sctp_sndrcvinfo *sinfo)
717 if (!chunk->asoc->prsctp_enable)
720 if (SCTP_PR_TTL_ENABLED(sinfo->sinfo_flags))
721 chunk->prsctp_param =
722 jiffies + msecs_to_jiffies(sinfo->sinfo_timetolive);
723 else if (SCTP_PR_RTX_ENABLED(sinfo->sinfo_flags) ||
724 SCTP_PR_PRIO_ENABLED(sinfo->sinfo_flags))
725 chunk->prsctp_param = sinfo->sinfo_timetolive;
728 /* Make a DATA chunk for the given association from the provided
729 * parameters. However, do not populate the data payload.
731 struct sctp_chunk *sctp_make_datafrag_empty(struct sctp_association *asoc,
732 const struct sctp_sndrcvinfo *sinfo,
733 int data_len, __u8 flags, __u16 ssn,
736 struct sctp_chunk *retval;
737 struct sctp_datahdr dp;
740 /* We assign the TSN as LATE as possible, not here when
741 * creating the chunk.
744 dp.stream = htons(sinfo->sinfo_stream);
745 dp.ppid = sinfo->sinfo_ppid;
747 /* Set the flags for an unordered send. */
748 if (sinfo->sinfo_flags & SCTP_UNORDERED) {
749 flags |= SCTP_DATA_UNORDERED;
754 chunk_len = sizeof(dp) + data_len;
755 retval = sctp_make_data(asoc, flags, chunk_len, gfp);
759 retval->subh.data_hdr = sctp_addto_chunk(retval, sizeof(dp), &dp);
760 memcpy(&retval->sinfo, sinfo, sizeof(struct sctp_sndrcvinfo));
761 sctp_set_prsctp_policy(retval, sinfo);
767 /* Create a selective ackowledgement (SACK) for the given
768 * association. This reports on which TSN's we've seen to date,
769 * including duplicates and gaps.
771 struct sctp_chunk *sctp_make_sack(const struct sctp_association *asoc)
773 struct sctp_chunk *retval;
774 struct sctp_sackhdr sack;
777 __u16 num_gabs, num_dup_tsns;
778 struct sctp_association *aptr = (struct sctp_association *)asoc;
779 struct sctp_tsnmap *map = (struct sctp_tsnmap *)&asoc->peer.tsn_map;
780 struct sctp_gap_ack_block gabs[SCTP_MAX_GABS];
781 struct sctp_transport *trans;
783 memset(gabs, 0, sizeof(gabs));
784 ctsn = sctp_tsnmap_get_ctsn(map);
786 pr_debug("%s: sackCTSNAck sent:0x%x\n", __func__, ctsn);
788 /* How much room is needed in the chunk? */
789 num_gabs = sctp_tsnmap_num_gabs(map, gabs);
790 num_dup_tsns = sctp_tsnmap_num_dups(map);
792 /* Initialize the SACK header. */
793 sack.cum_tsn_ack = htonl(ctsn);
794 sack.a_rwnd = htonl(asoc->a_rwnd);
795 sack.num_gap_ack_blocks = htons(num_gabs);
796 sack.num_dup_tsns = htons(num_dup_tsns);
799 + sizeof(struct sctp_gap_ack_block) * num_gabs
800 + sizeof(__u32) * num_dup_tsns;
802 /* Create the chunk. */
803 retval = sctp_make_control(asoc, SCTP_CID_SACK, 0, len, GFP_ATOMIC);
807 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
809 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
810 * HEARTBEAT ACK, etc.) to the same destination transport
811 * address from which it received the DATA or control chunk to
812 * which it is replying. This rule should also be followed if
813 * the endpoint is bundling DATA chunks together with the
816 * However, when acknowledging multiple DATA chunks received
817 * in packets from different source addresses in a single
818 * SACK, the SACK chunk may be transmitted to one of the
819 * destination transport addresses from which the DATA or
820 * control chunks being acknowledged were received.
822 * [BUG: We do not implement the following paragraph.
823 * Perhaps we should remember the last transport we used for a
824 * SACK and avoid that (if possible) if we have seen any
825 * duplicates. --piggy]
827 * When a receiver of a duplicate DATA chunk sends a SACK to a
828 * multi- homed endpoint it MAY be beneficial to vary the
829 * destination address and not use the source address of the
830 * DATA chunk. The reason being that receiving a duplicate
831 * from a multi-homed endpoint might indicate that the return
832 * path (as specified in the source address of the DATA chunk)
833 * for the SACK is broken.
835 * [Send to the address from which we last received a DATA chunk.]
837 retval->transport = asoc->peer.last_data_from;
839 retval->subh.sack_hdr =
840 sctp_addto_chunk(retval, sizeof(sack), &sack);
842 /* Add the gap ack block information. */
844 sctp_addto_chunk(retval, sizeof(__u32) * num_gabs,
847 /* Add the duplicate TSN information. */
849 aptr->stats.idupchunks += num_dup_tsns;
850 sctp_addto_chunk(retval, sizeof(__u32) * num_dup_tsns,
851 sctp_tsnmap_get_dups(map));
853 /* Once we have a sack generated, check to see what our sack
854 * generation is, if its 0, reset the transports to 0, and reset
855 * the association generation to 1
857 * The idea is that zero is never used as a valid generation for the
858 * association so no transport will match after a wrap event like this,
859 * Until the next sack
861 if (++aptr->peer.sack_generation == 0) {
862 list_for_each_entry(trans, &asoc->peer.transport_addr_list,
864 trans->sack_generation = 0;
865 aptr->peer.sack_generation = 1;
871 /* Make a SHUTDOWN chunk. */
872 struct sctp_chunk *sctp_make_shutdown(const struct sctp_association *asoc,
873 const struct sctp_chunk *chunk)
875 struct sctp_chunk *retval;
876 sctp_shutdownhdr_t shut;
879 ctsn = sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map);
880 shut.cum_tsn_ack = htonl(ctsn);
882 retval = sctp_make_control(asoc, SCTP_CID_SHUTDOWN, 0,
883 sizeof(sctp_shutdownhdr_t), GFP_ATOMIC);
887 retval->subh.shutdown_hdr =
888 sctp_addto_chunk(retval, sizeof(shut), &shut);
891 retval->transport = chunk->transport;
896 struct sctp_chunk *sctp_make_shutdown_ack(const struct sctp_association *asoc,
897 const struct sctp_chunk *chunk)
899 struct sctp_chunk *retval;
901 retval = sctp_make_control(asoc, SCTP_CID_SHUTDOWN_ACK, 0, 0,
904 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
906 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
907 * HEARTBEAT ACK, * etc.) to the same destination transport
908 * address from which it * received the DATA or control chunk
909 * to which it is replying.
911 * [ACK back to where the SHUTDOWN came from.]
914 retval->transport = chunk->transport;
919 struct sctp_chunk *sctp_make_shutdown_complete(
920 const struct sctp_association *asoc,
921 const struct sctp_chunk *chunk)
923 struct sctp_chunk *retval;
926 /* Set the T-bit if we have no association (vtag will be
929 flags |= asoc ? 0 : SCTP_CHUNK_FLAG_T;
931 retval = sctp_make_control(asoc, SCTP_CID_SHUTDOWN_COMPLETE, flags,
934 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
936 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
937 * HEARTBEAT ACK, * etc.) to the same destination transport
938 * address from which it * received the DATA or control chunk
939 * to which it is replying.
941 * [Report SHUTDOWN COMPLETE back to where the SHUTDOWN ACK
945 retval->transport = chunk->transport;
950 /* Create an ABORT. Note that we set the T bit if we have no
951 * association, except when responding to an INIT (sctpimpguide 2.41).
953 struct sctp_chunk *sctp_make_abort(const struct sctp_association *asoc,
954 const struct sctp_chunk *chunk,
957 struct sctp_chunk *retval;
960 /* Set the T-bit if we have no association and 'chunk' is not
961 * an INIT (vtag will be reflected).
964 if (chunk && chunk->chunk_hdr &&
965 chunk->chunk_hdr->type == SCTP_CID_INIT)
968 flags = SCTP_CHUNK_FLAG_T;
971 retval = sctp_make_control(asoc, SCTP_CID_ABORT, flags, hint,
974 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
976 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
977 * HEARTBEAT ACK, * etc.) to the same destination transport
978 * address from which it * received the DATA or control chunk
979 * to which it is replying.
981 * [ABORT back to where the offender came from.]
984 retval->transport = chunk->transport;
989 /* Helper to create ABORT with a NO_USER_DATA error. */
990 struct sctp_chunk *sctp_make_abort_no_data(
991 const struct sctp_association *asoc,
992 const struct sctp_chunk *chunk, __u32 tsn)
994 struct sctp_chunk *retval;
997 retval = sctp_make_abort(asoc, chunk, sizeof(sctp_errhdr_t)
1003 /* Put the tsn back into network byte order. */
1004 payload = htonl(tsn);
1005 sctp_init_cause(retval, SCTP_ERROR_NO_DATA, sizeof(payload));
1006 sctp_addto_chunk(retval, sizeof(payload), (const void *)&payload);
1008 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
1010 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
1011 * HEARTBEAT ACK, * etc.) to the same destination transport
1012 * address from which it * received the DATA or control chunk
1013 * to which it is replying.
1015 * [ABORT back to where the offender came from.]
1018 retval->transport = chunk->transport;
1024 /* Helper to create ABORT with a SCTP_ERROR_USER_ABORT error. */
1025 struct sctp_chunk *sctp_make_abort_user(const struct sctp_association *asoc,
1029 struct sctp_chunk *retval;
1030 void *payload = NULL;
1033 retval = sctp_make_abort(asoc, NULL, sizeof(sctp_errhdr_t) + paylen);
1038 /* Put the msg_iov together into payload. */
1039 payload = kmalloc(paylen, GFP_KERNEL);
1043 err = memcpy_from_msg(payload, msg, paylen);
1048 sctp_init_cause(retval, SCTP_ERROR_USER_ABORT, paylen);
1049 sctp_addto_chunk(retval, paylen, payload);
1059 sctp_chunk_free(retval);
1065 /* Append bytes to the end of a parameter. Will panic if chunk is not big
1068 static void *sctp_addto_param(struct sctp_chunk *chunk, int len,
1072 int chunklen = ntohs(chunk->chunk_hdr->length);
1074 target = skb_put(chunk->skb, len);
1077 memcpy(target, data, len);
1079 memset(target, 0, len);
1081 /* Adjust the chunk length field. */
1082 chunk->chunk_hdr->length = htons(chunklen + len);
1083 chunk->chunk_end = skb_tail_pointer(chunk->skb);
1088 /* Make an ABORT chunk with a PROTOCOL VIOLATION cause code. */
1089 struct sctp_chunk *sctp_make_abort_violation(
1090 const struct sctp_association *asoc,
1091 const struct sctp_chunk *chunk,
1092 const __u8 *payload,
1093 const size_t paylen)
1095 struct sctp_chunk *retval;
1096 struct sctp_paramhdr phdr;
1098 retval = sctp_make_abort(asoc, chunk, sizeof(sctp_errhdr_t) + paylen
1099 + sizeof(sctp_paramhdr_t));
1103 sctp_init_cause(retval, SCTP_ERROR_PROTO_VIOLATION, paylen
1104 + sizeof(sctp_paramhdr_t));
1106 phdr.type = htons(chunk->chunk_hdr->type);
1107 phdr.length = chunk->chunk_hdr->length;
1108 sctp_addto_chunk(retval, paylen, payload);
1109 sctp_addto_param(retval, sizeof(sctp_paramhdr_t), &phdr);
1115 struct sctp_chunk *sctp_make_violation_paramlen(
1116 const struct sctp_association *asoc,
1117 const struct sctp_chunk *chunk,
1118 struct sctp_paramhdr *param)
1120 struct sctp_chunk *retval;
1121 static const char error[] = "The following parameter had invalid length:";
1122 size_t payload_len = sizeof(error) + sizeof(sctp_errhdr_t) +
1123 sizeof(sctp_paramhdr_t);
1125 retval = sctp_make_abort(asoc, chunk, payload_len);
1129 sctp_init_cause(retval, SCTP_ERROR_PROTO_VIOLATION,
1130 sizeof(error) + sizeof(sctp_paramhdr_t));
1131 sctp_addto_chunk(retval, sizeof(error), error);
1132 sctp_addto_param(retval, sizeof(sctp_paramhdr_t), param);
1138 struct sctp_chunk *sctp_make_violation_max_retrans(
1139 const struct sctp_association *asoc,
1140 const struct sctp_chunk *chunk)
1142 struct sctp_chunk *retval;
1143 static const char error[] = "Association exceeded its max_retans count";
1144 size_t payload_len = sizeof(error) + sizeof(sctp_errhdr_t);
1146 retval = sctp_make_abort(asoc, chunk, payload_len);
1150 sctp_init_cause(retval, SCTP_ERROR_PROTO_VIOLATION, sizeof(error));
1151 sctp_addto_chunk(retval, sizeof(error), error);
1157 /* Make a HEARTBEAT chunk. */
1158 struct sctp_chunk *sctp_make_heartbeat(const struct sctp_association *asoc,
1159 const struct sctp_transport *transport)
1161 struct sctp_chunk *retval;
1162 sctp_sender_hb_info_t hbinfo;
1164 retval = sctp_make_control(asoc, SCTP_CID_HEARTBEAT, 0,
1165 sizeof(hbinfo), GFP_ATOMIC);
1170 hbinfo.param_hdr.type = SCTP_PARAM_HEARTBEAT_INFO;
1171 hbinfo.param_hdr.length = htons(sizeof(sctp_sender_hb_info_t));
1172 hbinfo.daddr = transport->ipaddr;
1173 hbinfo.sent_at = jiffies;
1174 hbinfo.hb_nonce = transport->hb_nonce;
1176 /* Cast away the 'const', as this is just telling the chunk
1177 * what transport it belongs to.
1179 retval->transport = (struct sctp_transport *) transport;
1180 retval->subh.hbs_hdr = sctp_addto_chunk(retval, sizeof(hbinfo),
1187 struct sctp_chunk *sctp_make_heartbeat_ack(const struct sctp_association *asoc,
1188 const struct sctp_chunk *chunk,
1189 const void *payload, const size_t paylen)
1191 struct sctp_chunk *retval;
1193 retval = sctp_make_control(asoc, SCTP_CID_HEARTBEAT_ACK, 0, paylen,
1198 retval->subh.hbs_hdr = sctp_addto_chunk(retval, paylen, payload);
1200 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
1202 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
1203 * HEARTBEAT ACK, * etc.) to the same destination transport
1204 * address from which it * received the DATA or control chunk
1205 * to which it is replying.
1207 * [HBACK back to where the HEARTBEAT came from.]
1210 retval->transport = chunk->transport;
1216 /* Create an Operation Error chunk with the specified space reserved.
1217 * This routine can be used for containing multiple causes in the chunk.
1219 static struct sctp_chunk *sctp_make_op_error_space(
1220 const struct sctp_association *asoc,
1221 const struct sctp_chunk *chunk,
1224 struct sctp_chunk *retval;
1226 retval = sctp_make_control(asoc, SCTP_CID_ERROR, 0,
1227 sizeof(sctp_errhdr_t) + size, GFP_ATOMIC);
1231 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
1233 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
1234 * HEARTBEAT ACK, etc.) to the same destination transport
1235 * address from which it received the DATA or control chunk
1236 * to which it is replying.
1240 retval->transport = chunk->transport;
1246 /* Create an Operation Error chunk of a fixed size,
1247 * specifically, max(asoc->pathmtu, SCTP_DEFAULT_MAXSEGMENT)
1248 * This is a helper function to allocate an error chunk for
1249 * for those invalid parameter codes in which we may not want
1250 * to report all the errors, if the incoming chunk is large
1252 static inline struct sctp_chunk *sctp_make_op_error_fixed(
1253 const struct sctp_association *asoc,
1254 const struct sctp_chunk *chunk)
1256 size_t size = asoc ? asoc->pathmtu : 0;
1259 size = SCTP_DEFAULT_MAXSEGMENT;
1261 return sctp_make_op_error_space(asoc, chunk, size);
1264 /* Create an Operation Error chunk. */
1265 struct sctp_chunk *sctp_make_op_error(const struct sctp_association *asoc,
1266 const struct sctp_chunk *chunk,
1267 __be16 cause_code, const void *payload,
1268 size_t paylen, size_t reserve_tail)
1270 struct sctp_chunk *retval;
1272 retval = sctp_make_op_error_space(asoc, chunk, paylen + reserve_tail);
1276 sctp_init_cause(retval, cause_code, paylen + reserve_tail);
1277 sctp_addto_chunk(retval, paylen, payload);
1279 sctp_addto_param(retval, reserve_tail, NULL);
1285 struct sctp_chunk *sctp_make_auth(const struct sctp_association *asoc)
1287 struct sctp_chunk *retval;
1288 struct sctp_hmac *hmac_desc;
1289 struct sctp_authhdr auth_hdr;
1292 /* Get the first hmac that the peer told us to use */
1293 hmac_desc = sctp_auth_asoc_get_hmac(asoc);
1294 if (unlikely(!hmac_desc))
1297 retval = sctp_make_control(asoc, SCTP_CID_AUTH, 0,
1298 hmac_desc->hmac_len + sizeof(sctp_authhdr_t),
1303 auth_hdr.hmac_id = htons(hmac_desc->hmac_id);
1304 auth_hdr.shkey_id = htons(asoc->active_key_id);
1306 retval->subh.auth_hdr = sctp_addto_chunk(retval, sizeof(sctp_authhdr_t),
1309 hmac = skb_put(retval->skb, hmac_desc->hmac_len);
1310 memset(hmac, 0, hmac_desc->hmac_len);
1312 /* Adjust the chunk header to include the empty MAC */
1313 retval->chunk_hdr->length =
1314 htons(ntohs(retval->chunk_hdr->length) + hmac_desc->hmac_len);
1315 retval->chunk_end = skb_tail_pointer(retval->skb);
1321 /********************************************************************
1322 * 2nd Level Abstractions
1323 ********************************************************************/
1325 /* Turn an skb into a chunk.
1326 * FIXME: Eventually move the structure directly inside the skb->cb[].
1328 * sctpimpguide-05.txt Section 2.8.2
1329 * M1) Each time a new DATA chunk is transmitted
1330 * set the 'TSN.Missing.Report' count for that TSN to 0. The
1331 * 'TSN.Missing.Report' count will be used to determine missing chunks
1332 * and when to fast retransmit.
1335 struct sctp_chunk *sctp_chunkify(struct sk_buff *skb,
1336 const struct sctp_association *asoc,
1337 struct sock *sk, gfp_t gfp)
1339 struct sctp_chunk *retval;
1341 retval = kmem_cache_zalloc(sctp_chunk_cachep, gfp);
1346 pr_debug("%s: chunkifying skb:%p w/o an sk\n", __func__, skb);
1348 INIT_LIST_HEAD(&retval->list);
1350 retval->asoc = (struct sctp_association *)asoc;
1351 retval->singleton = 1;
1353 retval->fast_retransmit = SCTP_CAN_FRTX;
1355 /* Polish the bead hole. */
1356 INIT_LIST_HEAD(&retval->transmitted_list);
1357 INIT_LIST_HEAD(&retval->frag_list);
1358 SCTP_DBG_OBJCNT_INC(chunk);
1359 atomic_set(&retval->refcnt, 1);
1365 /* Set chunk->source and dest based on the IP header in chunk->skb. */
1366 void sctp_init_addrs(struct sctp_chunk *chunk, union sctp_addr *src,
1367 union sctp_addr *dest)
1369 memcpy(&chunk->source, src, sizeof(union sctp_addr));
1370 memcpy(&chunk->dest, dest, sizeof(union sctp_addr));
1373 /* Extract the source address from a chunk. */
1374 const union sctp_addr *sctp_source(const struct sctp_chunk *chunk)
1376 /* If we have a known transport, use that. */
1377 if (chunk->transport) {
1378 return &chunk->transport->ipaddr;
1380 /* Otherwise, extract it from the IP header. */
1381 return &chunk->source;
1385 /* Create a new chunk, setting the type and flags headers from the
1386 * arguments, reserving enough space for a 'paylen' byte payload.
1388 static struct sctp_chunk *_sctp_make_chunk(const struct sctp_association *asoc,
1389 __u8 type, __u8 flags, int paylen,
1392 struct sctp_chunk *retval;
1393 sctp_chunkhdr_t *chunk_hdr;
1394 struct sk_buff *skb;
1397 /* No need to allocate LL here, as this is only a chunk. */
1398 skb = alloc_skb(WORD_ROUND(sizeof(sctp_chunkhdr_t) + paylen), gfp);
1402 /* Make room for the chunk header. */
1403 chunk_hdr = (sctp_chunkhdr_t *)skb_put(skb, sizeof(sctp_chunkhdr_t));
1404 chunk_hdr->type = type;
1405 chunk_hdr->flags = flags;
1406 chunk_hdr->length = htons(sizeof(sctp_chunkhdr_t));
1408 sk = asoc ? asoc->base.sk : NULL;
1409 retval = sctp_chunkify(skb, asoc, sk, gfp);
1415 retval->chunk_hdr = chunk_hdr;
1416 retval->chunk_end = ((__u8 *)chunk_hdr) + sizeof(struct sctp_chunkhdr);
1418 /* Determine if the chunk needs to be authenticated */
1419 if (sctp_auth_send_cid(type, asoc))
1427 static struct sctp_chunk *sctp_make_data(const struct sctp_association *asoc,
1428 __u8 flags, int paylen, gfp_t gfp)
1430 return _sctp_make_chunk(asoc, SCTP_CID_DATA, flags, paylen, gfp);
1433 static struct sctp_chunk *sctp_make_control(const struct sctp_association *asoc,
1434 __u8 type, __u8 flags, int paylen,
1437 struct sctp_chunk *chunk;
1439 chunk = _sctp_make_chunk(asoc, type, flags, paylen, gfp);
1441 sctp_control_set_owner_w(chunk);
1446 /* Release the memory occupied by a chunk. */
1447 static void sctp_chunk_destroy(struct sctp_chunk *chunk)
1449 BUG_ON(!list_empty(&chunk->list));
1450 list_del_init(&chunk->transmitted_list);
1452 consume_skb(chunk->skb);
1453 consume_skb(chunk->auth_chunk);
1455 SCTP_DBG_OBJCNT_DEC(chunk);
1456 kmem_cache_free(sctp_chunk_cachep, chunk);
1459 /* Possibly, free the chunk. */
1460 void sctp_chunk_free(struct sctp_chunk *chunk)
1462 /* Release our reference on the message tracker. */
1464 sctp_datamsg_put(chunk->msg);
1466 sctp_chunk_put(chunk);
1469 /* Grab a reference to the chunk. */
1470 void sctp_chunk_hold(struct sctp_chunk *ch)
1472 atomic_inc(&ch->refcnt);
1475 /* Release a reference to the chunk. */
1476 void sctp_chunk_put(struct sctp_chunk *ch)
1478 if (atomic_dec_and_test(&ch->refcnt))
1479 sctp_chunk_destroy(ch);
1482 /* Append bytes to the end of a chunk. Will panic if chunk is not big
1485 void *sctp_addto_chunk(struct sctp_chunk *chunk, int len, const void *data)
1489 int chunklen = ntohs(chunk->chunk_hdr->length);
1490 int padlen = WORD_ROUND(chunklen) - chunklen;
1492 padding = skb_put(chunk->skb, padlen);
1493 target = skb_put(chunk->skb, len);
1495 memset(padding, 0, padlen);
1496 memcpy(target, data, len);
1498 /* Adjust the chunk length field. */
1499 chunk->chunk_hdr->length = htons(chunklen + padlen + len);
1500 chunk->chunk_end = skb_tail_pointer(chunk->skb);
1505 /* Append bytes to the end of a chunk. Returns NULL if there isn't sufficient
1506 * space in the chunk
1508 static void *sctp_addto_chunk_fixed(struct sctp_chunk *chunk,
1509 int len, const void *data)
1511 if (skb_tailroom(chunk->skb) >= len)
1512 return sctp_addto_chunk(chunk, len, data);
1517 /* Append bytes from user space to the end of a chunk. Will panic if
1518 * chunk is not big enough.
1519 * Returns a kernel err value.
1521 int sctp_user_addto_chunk(struct sctp_chunk *chunk, int len,
1522 struct iov_iter *from)
1527 /* Make room in chunk for data. */
1528 target = skb_put(chunk->skb, len);
1530 /* Copy data (whole iovec) into chunk */
1531 copied = copy_from_iter(target, len, from);
1535 /* Adjust the chunk length field. */
1536 chunk->chunk_hdr->length =
1537 htons(ntohs(chunk->chunk_hdr->length) + len);
1538 chunk->chunk_end = skb_tail_pointer(chunk->skb);
1543 /* Helper function to assign a TSN if needed. This assumes that both
1544 * the data_hdr and association have already been assigned.
1546 void sctp_chunk_assign_ssn(struct sctp_chunk *chunk)
1548 struct sctp_datamsg *msg;
1549 struct sctp_chunk *lchunk;
1550 struct sctp_stream *stream;
1557 /* All fragments will be on the same stream */
1558 sid = ntohs(chunk->subh.data_hdr->stream);
1559 stream = &chunk->asoc->ssnmap->out;
1561 /* Now assign the sequence number to the entire message.
1562 * All fragments must have the same stream sequence number.
1565 list_for_each_entry(lchunk, &msg->chunks, frag_list) {
1566 if (lchunk->chunk_hdr->flags & SCTP_DATA_UNORDERED) {
1569 if (lchunk->chunk_hdr->flags & SCTP_DATA_LAST_FRAG)
1570 ssn = sctp_ssn_next(stream, sid);
1572 ssn = sctp_ssn_peek(stream, sid);
1575 lchunk->subh.data_hdr->ssn = htons(ssn);
1576 lchunk->has_ssn = 1;
1580 /* Helper function to assign a TSN if needed. This assumes that both
1581 * the data_hdr and association have already been assigned.
1583 void sctp_chunk_assign_tsn(struct sctp_chunk *chunk)
1585 if (!chunk->has_tsn) {
1586 /* This is the last possible instant to
1589 chunk->subh.data_hdr->tsn =
1590 htonl(sctp_association_get_next_tsn(chunk->asoc));
1595 /* Create a CLOSED association to use with an incoming packet. */
1596 struct sctp_association *sctp_make_temp_asoc(const struct sctp_endpoint *ep,
1597 struct sctp_chunk *chunk,
1600 struct sctp_association *asoc;
1601 struct sk_buff *skb;
1605 /* Create the bare association. */
1606 scope = sctp_scope(sctp_source(chunk));
1607 asoc = sctp_association_new(ep, ep->base.sk, scope, gfp);
1612 /* Create an entry for the source address of the packet. */
1613 af = sctp_get_af_specific(ipver2af(ip_hdr(skb)->version));
1616 af->from_skb(&asoc->c.peer_addr, skb, 1);
1621 sctp_association_free(asoc);
1625 /* Build a cookie representing asoc.
1626 * This INCLUDES the param header needed to put the cookie in the INIT ACK.
1628 static sctp_cookie_param_t *sctp_pack_cookie(const struct sctp_endpoint *ep,
1629 const struct sctp_association *asoc,
1630 const struct sctp_chunk *init_chunk,
1632 const __u8 *raw_addrs, int addrs_len)
1634 sctp_cookie_param_t *retval;
1635 struct sctp_signed_cookie *cookie;
1636 int headersize, bodysize;
1638 /* Header size is static data prior to the actual cookie, including
1641 headersize = sizeof(sctp_paramhdr_t) +
1642 (sizeof(struct sctp_signed_cookie) -
1643 sizeof(struct sctp_cookie));
1644 bodysize = sizeof(struct sctp_cookie)
1645 + ntohs(init_chunk->chunk_hdr->length) + addrs_len;
1647 /* Pad out the cookie to a multiple to make the signature
1648 * functions simpler to write.
1650 if (bodysize % SCTP_COOKIE_MULTIPLE)
1651 bodysize += SCTP_COOKIE_MULTIPLE
1652 - (bodysize % SCTP_COOKIE_MULTIPLE);
1653 *cookie_len = headersize + bodysize;
1655 /* Clear this memory since we are sending this data structure
1656 * out on the network.
1658 retval = kzalloc(*cookie_len, GFP_ATOMIC);
1662 cookie = (struct sctp_signed_cookie *) retval->body;
1664 /* Set up the parameter header. */
1665 retval->p.type = SCTP_PARAM_STATE_COOKIE;
1666 retval->p.length = htons(*cookie_len);
1668 /* Copy the cookie part of the association itself. */
1669 cookie->c = asoc->c;
1670 /* Save the raw address list length in the cookie. */
1671 cookie->c.raw_addr_list_len = addrs_len;
1673 /* Remember PR-SCTP capability. */
1674 cookie->c.prsctp_capable = asoc->peer.prsctp_capable;
1676 /* Save adaptation indication in the cookie. */
1677 cookie->c.adaptation_ind = asoc->peer.adaptation_ind;
1679 /* Set an expiration time for the cookie. */
1680 cookie->c.expiration = ktime_add(asoc->cookie_life,
1683 /* Copy the peer's init packet. */
1684 memcpy(&cookie->c.peer_init[0], init_chunk->chunk_hdr,
1685 ntohs(init_chunk->chunk_hdr->length));
1687 /* Copy the raw local address list of the association. */
1688 memcpy((__u8 *)&cookie->c.peer_init[0] +
1689 ntohs(init_chunk->chunk_hdr->length), raw_addrs, addrs_len);
1691 if (sctp_sk(ep->base.sk)->hmac) {
1692 SHASH_DESC_ON_STACK(desc, sctp_sk(ep->base.sk)->hmac);
1695 /* Sign the message. */
1696 desc->tfm = sctp_sk(ep->base.sk)->hmac;
1699 err = crypto_shash_setkey(desc->tfm, ep->secret_key,
1700 sizeof(ep->secret_key)) ?:
1701 crypto_shash_digest(desc, (u8 *)&cookie->c, bodysize,
1703 shash_desc_zero(desc);
1717 /* Unpack the cookie from COOKIE ECHO chunk, recreating the association. */
1718 struct sctp_association *sctp_unpack_cookie(
1719 const struct sctp_endpoint *ep,
1720 const struct sctp_association *asoc,
1721 struct sctp_chunk *chunk, gfp_t gfp,
1722 int *error, struct sctp_chunk **errp)
1724 struct sctp_association *retval = NULL;
1725 struct sctp_signed_cookie *cookie;
1726 struct sctp_cookie *bear_cookie;
1727 int headersize, bodysize, fixed_size;
1728 __u8 *digest = ep->digest;
1731 struct sk_buff *skb = chunk->skb;
1734 /* Header size is static data prior to the actual cookie, including
1737 headersize = sizeof(sctp_chunkhdr_t) +
1738 (sizeof(struct sctp_signed_cookie) -
1739 sizeof(struct sctp_cookie));
1740 bodysize = ntohs(chunk->chunk_hdr->length) - headersize;
1741 fixed_size = headersize + sizeof(struct sctp_cookie);
1743 /* Verify that the chunk looks like it even has a cookie.
1744 * There must be enough room for our cookie and our peer's
1747 len = ntohs(chunk->chunk_hdr->length);
1748 if (len < fixed_size + sizeof(struct sctp_chunkhdr))
1751 /* Verify that the cookie has been padded out. */
1752 if (bodysize % SCTP_COOKIE_MULTIPLE)
1755 /* Process the cookie. */
1756 cookie = chunk->subh.cookie_hdr;
1757 bear_cookie = &cookie->c;
1759 if (!sctp_sk(ep->base.sk)->hmac)
1762 /* Check the signature. */
1764 SHASH_DESC_ON_STACK(desc, sctp_sk(ep->base.sk)->hmac);
1767 desc->tfm = sctp_sk(ep->base.sk)->hmac;
1770 err = crypto_shash_setkey(desc->tfm, ep->secret_key,
1771 sizeof(ep->secret_key)) ?:
1772 crypto_shash_digest(desc, (u8 *)bear_cookie, bodysize,
1774 shash_desc_zero(desc);
1777 *error = -SCTP_IERROR_NOMEM;
1782 if (memcmp(digest, cookie->signature, SCTP_SIGNATURE_SIZE)) {
1783 *error = -SCTP_IERROR_BAD_SIG;
1788 /* IG Section 2.35.2:
1789 * 3) Compare the port numbers and the verification tag contained
1790 * within the COOKIE ECHO chunk to the actual port numbers and the
1791 * verification tag within the SCTP common header of the received
1792 * packet. If these values do not match the packet MUST be silently
1795 if (ntohl(chunk->sctp_hdr->vtag) != bear_cookie->my_vtag) {
1796 *error = -SCTP_IERROR_BAD_TAG;
1800 if (chunk->sctp_hdr->source != bear_cookie->peer_addr.v4.sin_port ||
1801 ntohs(chunk->sctp_hdr->dest) != bear_cookie->my_port) {
1802 *error = -SCTP_IERROR_BAD_PORTS;
1806 /* Check to see if the cookie is stale. If there is already
1807 * an association, there is no need to check cookie's expiration
1808 * for init collision case of lost COOKIE ACK.
1809 * If skb has been timestamped, then use the stamp, otherwise
1810 * use current time. This introduces a small possibility that
1811 * that a cookie may be considered expired, but his would only slow
1812 * down the new association establishment instead of every packet.
1814 if (sock_flag(ep->base.sk, SOCK_TIMESTAMP))
1815 kt = skb_get_ktime(skb);
1817 kt = ktime_get_real();
1819 if (!asoc && ktime_before(bear_cookie->expiration, kt)) {
1821 * Section 3.3.10.3 Stale Cookie Error (3)
1825 * Stale Cookie Error: Indicates the receipt of a valid State
1826 * Cookie that has expired.
1828 len = ntohs(chunk->chunk_hdr->length);
1829 *errp = sctp_make_op_error_space(asoc, chunk, len);
1831 suseconds_t usecs = ktime_to_us(ktime_sub(kt, bear_cookie->expiration));
1832 __be32 n = htonl(usecs);
1834 sctp_init_cause(*errp, SCTP_ERROR_STALE_COOKIE,
1836 sctp_addto_chunk(*errp, sizeof(n), &n);
1837 *error = -SCTP_IERROR_STALE_COOKIE;
1839 *error = -SCTP_IERROR_NOMEM;
1844 /* Make a new base association. */
1845 scope = sctp_scope(sctp_source(chunk));
1846 retval = sctp_association_new(ep, ep->base.sk, scope, gfp);
1848 *error = -SCTP_IERROR_NOMEM;
1852 /* Set up our peer's port number. */
1853 retval->peer.port = ntohs(chunk->sctp_hdr->source);
1855 /* Populate the association from the cookie. */
1856 memcpy(&retval->c, bear_cookie, sizeof(*bear_cookie));
1858 if (sctp_assoc_set_bind_addr_from_cookie(retval, bear_cookie,
1860 *error = -SCTP_IERROR_NOMEM;
1864 /* Also, add the destination address. */
1865 if (list_empty(&retval->base.bind_addr.address_list)) {
1866 sctp_add_bind_addr(&retval->base.bind_addr, &chunk->dest,
1867 sizeof(chunk->dest), SCTP_ADDR_SRC,
1871 retval->next_tsn = retval->c.initial_tsn;
1872 retval->ctsn_ack_point = retval->next_tsn - 1;
1873 retval->addip_serial = retval->c.initial_tsn;
1874 retval->adv_peer_ack_point = retval->ctsn_ack_point;
1875 retval->peer.prsctp_capable = retval->c.prsctp_capable;
1876 retval->peer.adaptation_ind = retval->c.adaptation_ind;
1878 /* The INIT stuff will be done by the side effects. */
1883 sctp_association_free(retval);
1888 /* Yikes! The packet is either corrupt or deliberately
1891 *error = -SCTP_IERROR_MALFORMED;
1895 /********************************************************************
1896 * 3rd Level Abstractions
1897 ********************************************************************/
1899 struct __sctp_missing {
1905 * Report a missing mandatory parameter.
1907 static int sctp_process_missing_param(const struct sctp_association *asoc,
1908 sctp_param_t paramtype,
1909 struct sctp_chunk *chunk,
1910 struct sctp_chunk **errp)
1912 struct __sctp_missing report;
1915 len = WORD_ROUND(sizeof(report));
1917 /* Make an ERROR chunk, preparing enough room for
1918 * returning multiple unknown parameters.
1921 *errp = sctp_make_op_error_space(asoc, chunk, len);
1924 report.num_missing = htonl(1);
1925 report.type = paramtype;
1926 sctp_init_cause(*errp, SCTP_ERROR_MISS_PARAM,
1928 sctp_addto_chunk(*errp, sizeof(report), &report);
1931 /* Stop processing this chunk. */
1935 /* Report an Invalid Mandatory Parameter. */
1936 static int sctp_process_inv_mandatory(const struct sctp_association *asoc,
1937 struct sctp_chunk *chunk,
1938 struct sctp_chunk **errp)
1940 /* Invalid Mandatory Parameter Error has no payload. */
1943 *errp = sctp_make_op_error_space(asoc, chunk, 0);
1946 sctp_init_cause(*errp, SCTP_ERROR_INV_PARAM, 0);
1948 /* Stop processing this chunk. */
1952 static int sctp_process_inv_paramlength(const struct sctp_association *asoc,
1953 struct sctp_paramhdr *param,
1954 const struct sctp_chunk *chunk,
1955 struct sctp_chunk **errp)
1957 /* This is a fatal error. Any accumulated non-fatal errors are
1961 sctp_chunk_free(*errp);
1963 /* Create an error chunk and fill it in with our payload. */
1964 *errp = sctp_make_violation_paramlen(asoc, chunk, param);
1970 /* Do not attempt to handle the HOST_NAME parm. However, do
1971 * send back an indicator to the peer.
1973 static int sctp_process_hn_param(const struct sctp_association *asoc,
1974 union sctp_params param,
1975 struct sctp_chunk *chunk,
1976 struct sctp_chunk **errp)
1978 __u16 len = ntohs(param.p->length);
1980 /* Processing of the HOST_NAME parameter will generate an
1981 * ABORT. If we've accumulated any non-fatal errors, they
1982 * would be unrecognized parameters and we should not include
1983 * them in the ABORT.
1986 sctp_chunk_free(*errp);
1988 *errp = sctp_make_op_error_space(asoc, chunk, len);
1991 sctp_init_cause(*errp, SCTP_ERROR_DNS_FAILED, len);
1992 sctp_addto_chunk(*errp, len, param.v);
1995 /* Stop processing this chunk. */
1999 static int sctp_verify_ext_param(struct net *net, union sctp_params param)
2001 __u16 num_ext = ntohs(param.p->length) - sizeof(sctp_paramhdr_t);
2003 int have_asconf = 0;
2006 for (i = 0; i < num_ext; i++) {
2007 switch (param.ext->chunks[i]) {
2011 case SCTP_CID_ASCONF:
2012 case SCTP_CID_ASCONF_ACK:
2018 /* ADD-IP Security: The draft requires us to ABORT or ignore the
2019 * INIT/INIT-ACK if ADD-IP is listed, but AUTH is not. Do this
2020 * only if ADD-IP is turned on and we are not backward-compatible
2023 if (net->sctp.addip_noauth)
2026 if (net->sctp.addip_enable && !have_auth && have_asconf)
2032 static void sctp_process_ext_param(struct sctp_association *asoc,
2033 union sctp_params param)
2035 struct net *net = sock_net(asoc->base.sk);
2036 __u16 num_ext = ntohs(param.p->length) - sizeof(sctp_paramhdr_t);
2039 for (i = 0; i < num_ext; i++) {
2040 switch (param.ext->chunks[i]) {
2041 case SCTP_CID_FWD_TSN:
2042 if (asoc->prsctp_enable && !asoc->peer.prsctp_capable)
2043 asoc->peer.prsctp_capable = 1;
2046 /* if the peer reports AUTH, assume that he
2049 if (asoc->ep->auth_enable)
2050 asoc->peer.auth_capable = 1;
2052 case SCTP_CID_ASCONF:
2053 case SCTP_CID_ASCONF_ACK:
2054 if (net->sctp.addip_enable)
2055 asoc->peer.asconf_capable = 1;
2063 /* RFC 3.2.1 & the Implementers Guide 2.2.
2065 * The Parameter Types are encoded such that the
2066 * highest-order two bits specify the action that must be
2067 * taken if the processing endpoint does not recognize the
2070 * 00 - Stop processing this parameter; do not process any further
2071 * parameters within this chunk
2073 * 01 - Stop processing this parameter, do not process any further
2074 * parameters within this chunk, and report the unrecognized
2075 * parameter in an 'Unrecognized Parameter' ERROR chunk.
2077 * 10 - Skip this parameter and continue processing.
2079 * 11 - Skip this parameter and continue processing but
2080 * report the unrecognized parameter in an
2081 * 'Unrecognized Parameter' ERROR chunk.
2084 * SCTP_IERROR_NO_ERROR - continue with the chunk
2085 * SCTP_IERROR_ERROR - stop and report an error.
2086 * SCTP_IERROR_NOMEME - out of memory.
2088 static sctp_ierror_t sctp_process_unk_param(const struct sctp_association *asoc,
2089 union sctp_params param,
2090 struct sctp_chunk *chunk,
2091 struct sctp_chunk **errp)
2093 int retval = SCTP_IERROR_NO_ERROR;
2095 switch (param.p->type & SCTP_PARAM_ACTION_MASK) {
2096 case SCTP_PARAM_ACTION_DISCARD:
2097 retval = SCTP_IERROR_ERROR;
2099 case SCTP_PARAM_ACTION_SKIP:
2101 case SCTP_PARAM_ACTION_DISCARD_ERR:
2102 retval = SCTP_IERROR_ERROR;
2104 case SCTP_PARAM_ACTION_SKIP_ERR:
2105 /* Make an ERROR chunk, preparing enough room for
2106 * returning multiple unknown parameters.
2109 *errp = sctp_make_op_error_fixed(asoc, chunk);
2112 if (!sctp_init_cause_fixed(*errp, SCTP_ERROR_UNKNOWN_PARAM,
2113 WORD_ROUND(ntohs(param.p->length))))
2114 sctp_addto_chunk_fixed(*errp,
2115 WORD_ROUND(ntohs(param.p->length)),
2118 /* If there is no memory for generating the ERROR
2119 * report as specified, an ABORT will be triggered
2120 * to the peer and the association won't be
2123 retval = SCTP_IERROR_NOMEM;
2133 /* Verify variable length parameters
2135 * SCTP_IERROR_ABORT - trigger an ABORT
2136 * SCTP_IERROR_NOMEM - out of memory (abort)
2137 * SCTP_IERROR_ERROR - stop processing, trigger an ERROR
2138 * SCTP_IERROR_NO_ERROR - continue with the chunk
2140 static sctp_ierror_t sctp_verify_param(struct net *net,
2141 const struct sctp_endpoint *ep,
2142 const struct sctp_association *asoc,
2143 union sctp_params param,
2145 struct sctp_chunk *chunk,
2146 struct sctp_chunk **err_chunk)
2148 struct sctp_hmac_algo_param *hmacs;
2149 int retval = SCTP_IERROR_NO_ERROR;
2150 __u16 n_elt, id = 0;
2153 /* FIXME - This routine is not looking at each parameter per the
2154 * chunk type, i.e., unrecognized parameters should be further
2155 * identified based on the chunk id.
2158 switch (param.p->type) {
2159 case SCTP_PARAM_IPV4_ADDRESS:
2160 case SCTP_PARAM_IPV6_ADDRESS:
2161 case SCTP_PARAM_COOKIE_PRESERVATIVE:
2162 case SCTP_PARAM_SUPPORTED_ADDRESS_TYPES:
2163 case SCTP_PARAM_STATE_COOKIE:
2164 case SCTP_PARAM_HEARTBEAT_INFO:
2165 case SCTP_PARAM_UNRECOGNIZED_PARAMETERS:
2166 case SCTP_PARAM_ECN_CAPABLE:
2167 case SCTP_PARAM_ADAPTATION_LAYER_IND:
2170 case SCTP_PARAM_SUPPORTED_EXT:
2171 if (!sctp_verify_ext_param(net, param))
2172 return SCTP_IERROR_ABORT;
2175 case SCTP_PARAM_SET_PRIMARY:
2176 if (net->sctp.addip_enable)
2180 case SCTP_PARAM_HOST_NAME_ADDRESS:
2181 /* Tell the peer, we won't support this param. */
2182 sctp_process_hn_param(asoc, param, chunk, err_chunk);
2183 retval = SCTP_IERROR_ABORT;
2186 case SCTP_PARAM_FWD_TSN_SUPPORT:
2187 if (ep->prsctp_enable)
2191 case SCTP_PARAM_RANDOM:
2192 if (!ep->auth_enable)
2195 /* SCTP-AUTH: Secion 6.1
2196 * If the random number is not 32 byte long the association
2197 * MUST be aborted. The ABORT chunk SHOULD contain the error
2198 * cause 'Protocol Violation'.
2200 if (SCTP_AUTH_RANDOM_LENGTH !=
2201 ntohs(param.p->length) - sizeof(sctp_paramhdr_t)) {
2202 sctp_process_inv_paramlength(asoc, param.p,
2204 retval = SCTP_IERROR_ABORT;
2208 case SCTP_PARAM_CHUNKS:
2209 if (!ep->auth_enable)
2212 /* SCTP-AUTH: Section 3.2
2213 * The CHUNKS parameter MUST be included once in the INIT or
2214 * INIT-ACK chunk if the sender wants to receive authenticated
2215 * chunks. Its maximum length is 260 bytes.
2217 if (260 < ntohs(param.p->length)) {
2218 sctp_process_inv_paramlength(asoc, param.p,
2220 retval = SCTP_IERROR_ABORT;
2224 case SCTP_PARAM_HMAC_ALGO:
2225 if (!ep->auth_enable)
2228 hmacs = (struct sctp_hmac_algo_param *)param.p;
2229 n_elt = (ntohs(param.p->length) - sizeof(sctp_paramhdr_t)) >> 1;
2231 /* SCTP-AUTH: Section 6.1
2232 * The HMAC algorithm based on SHA-1 MUST be supported and
2233 * included in the HMAC-ALGO parameter.
2235 for (i = 0; i < n_elt; i++) {
2236 id = ntohs(hmacs->hmac_ids[i]);
2238 if (id == SCTP_AUTH_HMAC_ID_SHA1)
2242 if (id != SCTP_AUTH_HMAC_ID_SHA1) {
2243 sctp_process_inv_paramlength(asoc, param.p, chunk,
2245 retval = SCTP_IERROR_ABORT;
2250 pr_debug("%s: unrecognized param:%d for chunk:%d\n",
2251 __func__, ntohs(param.p->type), cid);
2253 retval = sctp_process_unk_param(asoc, param, chunk, err_chunk);
2259 /* Verify the INIT packet before we process it. */
2260 int sctp_verify_init(struct net *net, const struct sctp_endpoint *ep,
2261 const struct sctp_association *asoc, sctp_cid_t cid,
2262 sctp_init_chunk_t *peer_init, struct sctp_chunk *chunk,
2263 struct sctp_chunk **errp)
2265 union sctp_params param;
2266 bool has_cookie = false;
2269 /* Check for missing mandatory parameters. Note: Initial TSN is
2270 * also mandatory, but is not checked here since the valid range
2271 * is 0..2**32-1. RFC4960, section 3.3.3.
2273 if (peer_init->init_hdr.num_outbound_streams == 0 ||
2274 peer_init->init_hdr.num_inbound_streams == 0 ||
2275 peer_init->init_hdr.init_tag == 0 ||
2276 ntohl(peer_init->init_hdr.a_rwnd) < SCTP_DEFAULT_MINWINDOW)
2277 return sctp_process_inv_mandatory(asoc, chunk, errp);
2279 sctp_walk_params(param, peer_init, init_hdr.params) {
2280 if (param.p->type == SCTP_PARAM_STATE_COOKIE)
2284 /* There is a possibility that a parameter length was bad and
2285 * in that case we would have stoped walking the parameters.
2286 * The current param.p would point at the bad one.
2287 * Current consensus on the mailing list is to generate a PROTOCOL
2288 * VIOLATION error. We build the ERROR chunk here and let the normal
2289 * error handling code build and send the packet.
2291 if (param.v != (void *)chunk->chunk_end)
2292 return sctp_process_inv_paramlength(asoc, param.p, chunk, errp);
2294 /* The only missing mandatory param possible today is
2295 * the state cookie for an INIT-ACK chunk.
2297 if ((SCTP_CID_INIT_ACK == cid) && !has_cookie)
2298 return sctp_process_missing_param(asoc, SCTP_PARAM_STATE_COOKIE,
2301 /* Verify all the variable length parameters */
2302 sctp_walk_params(param, peer_init, init_hdr.params) {
2303 result = sctp_verify_param(net, ep, asoc, param, cid,
2306 case SCTP_IERROR_ABORT:
2307 case SCTP_IERROR_NOMEM:
2309 case SCTP_IERROR_ERROR:
2311 case SCTP_IERROR_NO_ERROR:
2316 } /* for (loop through all parameters) */
2321 /* Unpack the parameters in an INIT packet into an association.
2322 * Returns 0 on failure, else success.
2323 * FIXME: This is an association method.
2325 int sctp_process_init(struct sctp_association *asoc, struct sctp_chunk *chunk,
2326 const union sctp_addr *peer_addr,
2327 sctp_init_chunk_t *peer_init, gfp_t gfp)
2329 struct net *net = sock_net(asoc->base.sk);
2330 union sctp_params param;
2331 struct sctp_transport *transport;
2332 struct list_head *pos, *temp;
2334 union sctp_addr addr;
2338 /* We must include the address that the INIT packet came from.
2339 * This is the only address that matters for an INIT packet.
2340 * When processing a COOKIE ECHO, we retrieve the from address
2341 * of the INIT from the cookie.
2344 /* This implementation defaults to making the first transport
2345 * added as the primary transport. The source address seems to
2346 * be a a better choice than any of the embedded addresses.
2348 if (!sctp_assoc_add_peer(asoc, peer_addr, gfp, SCTP_ACTIVE))
2351 if (sctp_cmp_addr_exact(sctp_source(chunk), peer_addr))
2354 /* Process the initialization parameters. */
2355 sctp_walk_params(param, peer_init, init_hdr.params) {
2356 if (!src_match && (param.p->type == SCTP_PARAM_IPV4_ADDRESS ||
2357 param.p->type == SCTP_PARAM_IPV6_ADDRESS)) {
2358 af = sctp_get_af_specific(param_type2af(param.p->type));
2359 af->from_addr_param(&addr, param.addr,
2360 chunk->sctp_hdr->source, 0);
2361 if (sctp_cmp_addr_exact(sctp_source(chunk), &addr))
2365 if (!sctp_process_param(asoc, param, peer_addr, gfp))
2369 /* source address of chunk may not match any valid address */
2373 /* AUTH: After processing the parameters, make sure that we
2374 * have all the required info to potentially do authentications.
2376 if (asoc->peer.auth_capable && (!asoc->peer.peer_random ||
2377 !asoc->peer.peer_hmacs))
2378 asoc->peer.auth_capable = 0;
2380 /* In a non-backward compatible mode, if the peer claims
2381 * support for ADD-IP but not AUTH, the ADD-IP spec states
2382 * that we MUST ABORT the association. Section 6. The section
2383 * also give us an option to silently ignore the packet, which
2384 * is what we'll do here.
2386 if (!net->sctp.addip_noauth &&
2387 (asoc->peer.asconf_capable && !asoc->peer.auth_capable)) {
2388 asoc->peer.addip_disabled_mask |= (SCTP_PARAM_ADD_IP |
2390 SCTP_PARAM_SET_PRIMARY);
2391 asoc->peer.asconf_capable = 0;
2395 /* Walk list of transports, removing transports in the UNKNOWN state. */
2396 list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
2397 transport = list_entry(pos, struct sctp_transport, transports);
2398 if (transport->state == SCTP_UNKNOWN) {
2399 sctp_assoc_rm_peer(asoc, transport);
2403 /* The fixed INIT headers are always in network byte
2406 asoc->peer.i.init_tag =
2407 ntohl(peer_init->init_hdr.init_tag);
2408 asoc->peer.i.a_rwnd =
2409 ntohl(peer_init->init_hdr.a_rwnd);
2410 asoc->peer.i.num_outbound_streams =
2411 ntohs(peer_init->init_hdr.num_outbound_streams);
2412 asoc->peer.i.num_inbound_streams =
2413 ntohs(peer_init->init_hdr.num_inbound_streams);
2414 asoc->peer.i.initial_tsn =
2415 ntohl(peer_init->init_hdr.initial_tsn);
2417 /* Apply the upper bounds for output streams based on peer's
2418 * number of inbound streams.
2420 if (asoc->c.sinit_num_ostreams >
2421 ntohs(peer_init->init_hdr.num_inbound_streams)) {
2422 asoc->c.sinit_num_ostreams =
2423 ntohs(peer_init->init_hdr.num_inbound_streams);
2426 if (asoc->c.sinit_max_instreams >
2427 ntohs(peer_init->init_hdr.num_outbound_streams)) {
2428 asoc->c.sinit_max_instreams =
2429 ntohs(peer_init->init_hdr.num_outbound_streams);
2432 /* Copy Initiation tag from INIT to VT_peer in cookie. */
2433 asoc->c.peer_vtag = asoc->peer.i.init_tag;
2435 /* Peer Rwnd : Current calculated value of the peer's rwnd. */
2436 asoc->peer.rwnd = asoc->peer.i.a_rwnd;
2438 /* Copy cookie in case we need to resend COOKIE-ECHO. */
2439 cookie = asoc->peer.cookie;
2441 asoc->peer.cookie = kmemdup(cookie, asoc->peer.cookie_len, gfp);
2442 if (!asoc->peer.cookie)
2446 /* RFC 2960 7.2.1 The initial value of ssthresh MAY be arbitrarily
2447 * high (for example, implementations MAY use the size of the receiver
2448 * advertised window).
2450 list_for_each_entry(transport, &asoc->peer.transport_addr_list,
2452 transport->ssthresh = asoc->peer.i.a_rwnd;
2455 /* Set up the TSN tracking pieces. */
2456 if (!sctp_tsnmap_init(&asoc->peer.tsn_map, SCTP_TSN_MAP_INITIAL,
2457 asoc->peer.i.initial_tsn, gfp))
2460 /* RFC 2960 6.5 Stream Identifier and Stream Sequence Number
2462 * The stream sequence number in all the streams shall start
2463 * from 0 when the association is established. Also, when the
2464 * stream sequence number reaches the value 65535 the next
2465 * stream sequence number shall be set to 0.
2468 /* Allocate storage for the negotiated streams if it is not a temporary
2474 asoc->ssnmap = sctp_ssnmap_new(asoc->c.sinit_max_instreams,
2475 asoc->c.sinit_num_ostreams, gfp);
2479 error = sctp_assoc_set_id(asoc, gfp);
2484 /* ADDIP Section 4.1 ASCONF Chunk Procedures
2486 * When an endpoint has an ASCONF signaled change to be sent to the
2487 * remote endpoint it should do the following:
2489 * A2) A serial number should be assigned to the Chunk. The serial
2490 * number should be a monotonically increasing number. All serial
2491 * numbers are defined to be initialized at the start of the
2492 * association to the same value as the Initial TSN.
2494 asoc->peer.addip_serial = asoc->peer.i.initial_tsn - 1;
2498 /* Release the transport structures. */
2499 list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
2500 transport = list_entry(pos, struct sctp_transport, transports);
2501 if (transport->state != SCTP_ACTIVE)
2502 sctp_assoc_rm_peer(asoc, transport);
2510 /* Update asoc with the option described in param.
2512 * RFC2960 3.3.2.1 Optional/Variable Length Parameters in INIT
2514 * asoc is the association to update.
2515 * param is the variable length parameter to use for update.
2516 * cid tells us if this is an INIT, INIT ACK or COOKIE ECHO.
2517 * If the current packet is an INIT we want to minimize the amount of
2518 * work we do. In particular, we should not build transport
2519 * structures for the addresses.
2521 static int sctp_process_param(struct sctp_association *asoc,
2522 union sctp_params param,
2523 const union sctp_addr *peer_addr,
2526 struct net *net = sock_net(asoc->base.sk);
2527 union sctp_addr addr;
2534 union sctp_addr_param *addr_param;
2535 struct sctp_transport *t;
2536 struct sctp_endpoint *ep = asoc->ep;
2538 /* We maintain all INIT parameters in network byte order all the
2539 * time. This allows us to not worry about whether the parameters
2540 * came from a fresh INIT, and INIT ACK, or were stored in a cookie.
2542 switch (param.p->type) {
2543 case SCTP_PARAM_IPV6_ADDRESS:
2544 if (PF_INET6 != asoc->base.sk->sk_family)
2548 case SCTP_PARAM_IPV4_ADDRESS:
2549 /* v4 addresses are not allowed on v6-only socket */
2550 if (ipv6_only_sock(asoc->base.sk))
2553 af = sctp_get_af_specific(param_type2af(param.p->type));
2554 af->from_addr_param(&addr, param.addr, htons(asoc->peer.port), 0);
2555 scope = sctp_scope(peer_addr);
2556 if (sctp_in_scope(net, &addr, scope))
2557 if (!sctp_assoc_add_peer(asoc, &addr, gfp, SCTP_UNCONFIRMED))
2561 case SCTP_PARAM_COOKIE_PRESERVATIVE:
2562 if (!net->sctp.cookie_preserve_enable)
2565 stale = ntohl(param.life->lifespan_increment);
2567 /* Suggested Cookie Life span increment's unit is msec,
2570 asoc->cookie_life = ktime_add_ms(asoc->cookie_life, stale);
2573 case SCTP_PARAM_HOST_NAME_ADDRESS:
2574 pr_debug("%s: unimplemented SCTP_HOST_NAME_ADDRESS\n", __func__);
2577 case SCTP_PARAM_SUPPORTED_ADDRESS_TYPES:
2578 /* Turn off the default values first so we'll know which
2579 * ones are really set by the peer.
2581 asoc->peer.ipv4_address = 0;
2582 asoc->peer.ipv6_address = 0;
2584 /* Assume that peer supports the address family
2585 * by which it sends a packet.
2587 if (peer_addr->sa.sa_family == AF_INET6)
2588 asoc->peer.ipv6_address = 1;
2589 else if (peer_addr->sa.sa_family == AF_INET)
2590 asoc->peer.ipv4_address = 1;
2592 /* Cycle through address types; avoid divide by 0. */
2593 sat = ntohs(param.p->length) - sizeof(sctp_paramhdr_t);
2595 sat /= sizeof(__u16);
2597 for (i = 0; i < sat; ++i) {
2598 switch (param.sat->types[i]) {
2599 case SCTP_PARAM_IPV4_ADDRESS:
2600 asoc->peer.ipv4_address = 1;
2603 case SCTP_PARAM_IPV6_ADDRESS:
2604 if (PF_INET6 == asoc->base.sk->sk_family)
2605 asoc->peer.ipv6_address = 1;
2608 case SCTP_PARAM_HOST_NAME_ADDRESS:
2609 asoc->peer.hostname_address = 1;
2612 default: /* Just ignore anything else. */
2618 case SCTP_PARAM_STATE_COOKIE:
2619 asoc->peer.cookie_len =
2620 ntohs(param.p->length) - sizeof(sctp_paramhdr_t);
2621 asoc->peer.cookie = param.cookie->body;
2624 case SCTP_PARAM_HEARTBEAT_INFO:
2625 /* Would be odd to receive, but it causes no problems. */
2628 case SCTP_PARAM_UNRECOGNIZED_PARAMETERS:
2629 /* Rejected during verify stage. */
2632 case SCTP_PARAM_ECN_CAPABLE:
2633 asoc->peer.ecn_capable = 1;
2636 case SCTP_PARAM_ADAPTATION_LAYER_IND:
2637 asoc->peer.adaptation_ind = ntohl(param.aind->adaptation_ind);
2640 case SCTP_PARAM_SET_PRIMARY:
2641 if (!net->sctp.addip_enable)
2644 addr_param = param.v + sizeof(sctp_addip_param_t);
2646 af = sctp_get_af_specific(param_type2af(addr_param->p.type));
2650 af->from_addr_param(&addr, addr_param,
2651 htons(asoc->peer.port), 0);
2653 /* if the address is invalid, we can't process it.
2654 * XXX: see spec for what to do.
2656 if (!af->addr_valid(&addr, NULL, NULL))
2659 t = sctp_assoc_lookup_paddr(asoc, &addr);
2663 sctp_assoc_set_primary(asoc, t);
2666 case SCTP_PARAM_SUPPORTED_EXT:
2667 sctp_process_ext_param(asoc, param);
2670 case SCTP_PARAM_FWD_TSN_SUPPORT:
2671 if (asoc->prsctp_enable) {
2672 asoc->peer.prsctp_capable = 1;
2678 case SCTP_PARAM_RANDOM:
2679 if (!ep->auth_enable)
2682 /* Save peer's random parameter */
2683 asoc->peer.peer_random = kmemdup(param.p,
2684 ntohs(param.p->length), gfp);
2685 if (!asoc->peer.peer_random) {
2691 case SCTP_PARAM_HMAC_ALGO:
2692 if (!ep->auth_enable)
2695 /* Save peer's HMAC list */
2696 asoc->peer.peer_hmacs = kmemdup(param.p,
2697 ntohs(param.p->length), gfp);
2698 if (!asoc->peer.peer_hmacs) {
2703 /* Set the default HMAC the peer requested*/
2704 sctp_auth_asoc_set_default_hmac(asoc, param.hmac_algo);
2707 case SCTP_PARAM_CHUNKS:
2708 if (!ep->auth_enable)
2711 asoc->peer.peer_chunks = kmemdup(param.p,
2712 ntohs(param.p->length), gfp);
2713 if (!asoc->peer.peer_chunks)
2718 /* Any unrecognized parameters should have been caught
2719 * and handled by sctp_verify_param() which should be
2720 * called prior to this routine. Simply log the error
2723 pr_debug("%s: ignoring param:%d for association:%p.\n",
2724 __func__, ntohs(param.p->type), asoc);
2731 /* Select a new verification tag. */
2732 __u32 sctp_generate_tag(const struct sctp_endpoint *ep)
2734 /* I believe that this random number generator complies with RFC1750.
2735 * A tag of 0 is reserved for special cases (e.g. INIT).
2740 get_random_bytes(&x, sizeof(__u32));
2746 /* Select an initial TSN to send during startup. */
2747 __u32 sctp_generate_tsn(const struct sctp_endpoint *ep)
2751 get_random_bytes(&retval, sizeof(__u32));
2756 * ADDIP 3.1.1 Address Configuration Change Chunk (ASCONF)
2758 * 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
2759 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2760 * | Type = 0xC1 | Chunk Flags | Chunk Length |
2761 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2763 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2764 * | Address Parameter |
2765 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2766 * | ASCONF Parameter #1 |
2767 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2771 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2772 * | ASCONF Parameter #N |
2773 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2775 * Address Parameter and other parameter will not be wrapped in this function
2777 static struct sctp_chunk *sctp_make_asconf(struct sctp_association *asoc,
2778 union sctp_addr *addr,
2781 sctp_addiphdr_t asconf;
2782 struct sctp_chunk *retval;
2783 int length = sizeof(asconf) + vparam_len;
2784 union sctp_addr_param addrparam;
2786 struct sctp_af *af = sctp_get_af_specific(addr->v4.sin_family);
2788 addrlen = af->to_addr_param(addr, &addrparam);
2793 /* Create the chunk. */
2794 retval = sctp_make_control(asoc, SCTP_CID_ASCONF, 0, length,
2799 asconf.serial = htonl(asoc->addip_serial++);
2801 retval->subh.addip_hdr =
2802 sctp_addto_chunk(retval, sizeof(asconf), &asconf);
2803 retval->param_hdr.v =
2804 sctp_addto_chunk(retval, addrlen, &addrparam);
2810 * 3.2.1 Add IP Address
2812 * 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
2813 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2814 * | Type = 0xC001 | Length = Variable |
2815 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2816 * | ASCONF-Request Correlation ID |
2817 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2818 * | Address Parameter |
2819 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2821 * 3.2.2 Delete IP Address
2823 * 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
2824 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2825 * | Type = 0xC002 | Length = Variable |
2826 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2827 * | ASCONF-Request Correlation ID |
2828 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2829 * | Address Parameter |
2830 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2833 struct sctp_chunk *sctp_make_asconf_update_ip(struct sctp_association *asoc,
2834 union sctp_addr *laddr,
2835 struct sockaddr *addrs,
2839 sctp_addip_param_t param;
2840 struct sctp_chunk *retval;
2841 union sctp_addr_param addr_param;
2842 union sctp_addr *addr;
2845 int paramlen = sizeof(param);
2846 int addr_param_len = 0;
2851 /* Get total length of all the address parameters. */
2853 for (i = 0; i < addrcnt; i++) {
2855 af = sctp_get_af_specific(addr->v4.sin_family);
2856 addr_param_len = af->to_addr_param(addr, &addr_param);
2858 totallen += paramlen;
2859 totallen += addr_param_len;
2861 addr_buf += af->sockaddr_len;
2862 if (asoc->asconf_addr_del_pending && !del_pickup) {
2863 /* reuse the parameter length from the same scope one */
2864 totallen += paramlen;
2865 totallen += addr_param_len;
2868 pr_debug("%s: picked same-scope del_pending addr, "
2869 "totallen for all addresses is %d\n",
2870 __func__, totallen);
2874 /* Create an asconf chunk with the required length. */
2875 retval = sctp_make_asconf(asoc, laddr, totallen);
2879 /* Add the address parameters to the asconf chunk. */
2881 for (i = 0; i < addrcnt; i++) {
2883 af = sctp_get_af_specific(addr->v4.sin_family);
2884 addr_param_len = af->to_addr_param(addr, &addr_param);
2885 param.param_hdr.type = flags;
2886 param.param_hdr.length = htons(paramlen + addr_param_len);
2889 sctp_addto_chunk(retval, paramlen, ¶m);
2890 sctp_addto_chunk(retval, addr_param_len, &addr_param);
2892 addr_buf += af->sockaddr_len;
2894 if (flags == SCTP_PARAM_ADD_IP && del_pickup) {
2895 addr = asoc->asconf_addr_del_pending;
2896 af = sctp_get_af_specific(addr->v4.sin_family);
2897 addr_param_len = af->to_addr_param(addr, &addr_param);
2898 param.param_hdr.type = SCTP_PARAM_DEL_IP;
2899 param.param_hdr.length = htons(paramlen + addr_param_len);
2902 sctp_addto_chunk(retval, paramlen, ¶m);
2903 sctp_addto_chunk(retval, addr_param_len, &addr_param);
2909 * 3.2.4 Set Primary IP Address
2911 * 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
2912 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2913 * | Type =0xC004 | Length = Variable |
2914 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2915 * | ASCONF-Request Correlation ID |
2916 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2917 * | Address Parameter |
2918 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2920 * Create an ASCONF chunk with Set Primary IP address parameter.
2922 struct sctp_chunk *sctp_make_asconf_set_prim(struct sctp_association *asoc,
2923 union sctp_addr *addr)
2925 sctp_addip_param_t param;
2926 struct sctp_chunk *retval;
2927 int len = sizeof(param);
2928 union sctp_addr_param addrparam;
2930 struct sctp_af *af = sctp_get_af_specific(addr->v4.sin_family);
2932 addrlen = af->to_addr_param(addr, &addrparam);
2937 /* Create the chunk and make asconf header. */
2938 retval = sctp_make_asconf(asoc, addr, len);
2942 param.param_hdr.type = SCTP_PARAM_SET_PRIMARY;
2943 param.param_hdr.length = htons(len);
2946 sctp_addto_chunk(retval, sizeof(param), ¶m);
2947 sctp_addto_chunk(retval, addrlen, &addrparam);
2952 /* ADDIP 3.1.2 Address Configuration Acknowledgement Chunk (ASCONF-ACK)
2954 * 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
2955 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2956 * | Type = 0x80 | Chunk Flags | Chunk Length |
2957 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2959 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2960 * | ASCONF Parameter Response#1 |
2961 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2965 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2966 * | ASCONF Parameter Response#N |
2967 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2969 * Create an ASCONF_ACK chunk with enough space for the parameter responses.
2971 static struct sctp_chunk *sctp_make_asconf_ack(const struct sctp_association *asoc,
2972 __u32 serial, int vparam_len)
2974 sctp_addiphdr_t asconf;
2975 struct sctp_chunk *retval;
2976 int length = sizeof(asconf) + vparam_len;
2978 /* Create the chunk. */
2979 retval = sctp_make_control(asoc, SCTP_CID_ASCONF_ACK, 0, length,
2984 asconf.serial = htonl(serial);
2986 retval->subh.addip_hdr =
2987 sctp_addto_chunk(retval, sizeof(asconf), &asconf);
2992 /* Add response parameters to an ASCONF_ACK chunk. */
2993 static void sctp_add_asconf_response(struct sctp_chunk *chunk, __be32 crr_id,
2994 __be16 err_code, sctp_addip_param_t *asconf_param)
2996 sctp_addip_param_t ack_param;
2997 sctp_errhdr_t err_param;
2998 int asconf_param_len = 0;
2999 int err_param_len = 0;
3000 __be16 response_type;
3002 if (SCTP_ERROR_NO_ERROR == err_code) {
3003 response_type = SCTP_PARAM_SUCCESS_REPORT;
3005 response_type = SCTP_PARAM_ERR_CAUSE;
3006 err_param_len = sizeof(err_param);
3009 ntohs(asconf_param->param_hdr.length);
3012 /* Add Success Indication or Error Cause Indication parameter. */
3013 ack_param.param_hdr.type = response_type;
3014 ack_param.param_hdr.length = htons(sizeof(ack_param) +
3017 ack_param.crr_id = crr_id;
3018 sctp_addto_chunk(chunk, sizeof(ack_param), &ack_param);
3020 if (SCTP_ERROR_NO_ERROR == err_code)
3023 /* Add Error Cause parameter. */
3024 err_param.cause = err_code;
3025 err_param.length = htons(err_param_len + asconf_param_len);
3026 sctp_addto_chunk(chunk, err_param_len, &err_param);
3028 /* Add the failed TLV copied from ASCONF chunk. */
3030 sctp_addto_chunk(chunk, asconf_param_len, asconf_param);
3033 /* Process a asconf parameter. */
3034 static __be16 sctp_process_asconf_param(struct sctp_association *asoc,
3035 struct sctp_chunk *asconf,
3036 sctp_addip_param_t *asconf_param)
3038 struct sctp_transport *peer;
3040 union sctp_addr addr;
3041 union sctp_addr_param *addr_param;
3043 addr_param = (void *)asconf_param + sizeof(sctp_addip_param_t);
3045 if (asconf_param->param_hdr.type != SCTP_PARAM_ADD_IP &&
3046 asconf_param->param_hdr.type != SCTP_PARAM_DEL_IP &&
3047 asconf_param->param_hdr.type != SCTP_PARAM_SET_PRIMARY)
3048 return SCTP_ERROR_UNKNOWN_PARAM;
3050 switch (addr_param->p.type) {
3051 case SCTP_PARAM_IPV6_ADDRESS:
3052 if (!asoc->peer.ipv6_address)
3053 return SCTP_ERROR_DNS_FAILED;
3055 case SCTP_PARAM_IPV4_ADDRESS:
3056 if (!asoc->peer.ipv4_address)
3057 return SCTP_ERROR_DNS_FAILED;
3060 return SCTP_ERROR_DNS_FAILED;
3063 af = sctp_get_af_specific(param_type2af(addr_param->p.type));
3065 return SCTP_ERROR_DNS_FAILED;
3067 af->from_addr_param(&addr, addr_param, htons(asoc->peer.port), 0);
3069 /* ADDIP 4.2.1 This parameter MUST NOT contain a broadcast
3070 * or multicast address.
3071 * (note: wildcard is permitted and requires special handling so
3072 * make sure we check for that)
3074 if (!af->is_any(&addr) && !af->addr_valid(&addr, NULL, asconf->skb))
3075 return SCTP_ERROR_DNS_FAILED;
3077 switch (asconf_param->param_hdr.type) {
3078 case SCTP_PARAM_ADD_IP:
3080 * If the address 0.0.0.0 or ::0 is provided, the source
3081 * address of the packet MUST be added.
3083 if (af->is_any(&addr))
3084 memcpy(&addr, &asconf->source, sizeof(addr));
3086 /* ADDIP 4.3 D9) If an endpoint receives an ADD IP address
3087 * request and does not have the local resources to add this
3088 * new address to the association, it MUST return an Error
3089 * Cause TLV set to the new error code 'Operation Refused
3090 * Due to Resource Shortage'.
3093 peer = sctp_assoc_add_peer(asoc, &addr, GFP_ATOMIC, SCTP_UNCONFIRMED);
3095 return SCTP_ERROR_RSRC_LOW;
3097 /* Start the heartbeat timer. */
3098 sctp_transport_reset_hb_timer(peer);
3099 asoc->new_transport = peer;
3101 case SCTP_PARAM_DEL_IP:
3102 /* ADDIP 4.3 D7) If a request is received to delete the
3103 * last remaining IP address of a peer endpoint, the receiver
3104 * MUST send an Error Cause TLV with the error cause set to the
3105 * new error code 'Request to Delete Last Remaining IP Address'.
3107 if (asoc->peer.transport_count == 1)
3108 return SCTP_ERROR_DEL_LAST_IP;
3110 /* ADDIP 4.3 D8) If a request is received to delete an IP
3111 * address which is also the source address of the IP packet
3112 * which contained the ASCONF chunk, the receiver MUST reject
3113 * this request. To reject the request the receiver MUST send
3114 * an Error Cause TLV set to the new error code 'Request to
3115 * Delete Source IP Address'
3117 if (sctp_cmp_addr_exact(&asconf->source, &addr))
3118 return SCTP_ERROR_DEL_SRC_IP;
3121 * If the address 0.0.0.0 or ::0 is provided, all
3122 * addresses of the peer except the source address of the
3123 * packet MUST be deleted.
3125 if (af->is_any(&addr)) {
3126 sctp_assoc_set_primary(asoc, asconf->transport);
3127 sctp_assoc_del_nonprimary_peers(asoc,
3129 return SCTP_ERROR_NO_ERROR;
3132 /* If the address is not part of the association, the
3133 * ASCONF-ACK with Error Cause Indication Parameter
3134 * which including cause of Unresolvable Address should
3137 peer = sctp_assoc_lookup_paddr(asoc, &addr);
3139 return SCTP_ERROR_DNS_FAILED;
3141 sctp_assoc_rm_peer(asoc, peer);
3143 case SCTP_PARAM_SET_PRIMARY:
3144 /* ADDIP Section 4.2.4
3145 * If the address 0.0.0.0 or ::0 is provided, the receiver
3146 * MAY mark the source address of the packet as its
3149 if (af->is_any(&addr))
3150 memcpy(&addr.v4, sctp_source(asconf), sizeof(addr));
3152 peer = sctp_assoc_lookup_paddr(asoc, &addr);
3154 return SCTP_ERROR_DNS_FAILED;
3156 sctp_assoc_set_primary(asoc, peer);
3160 return SCTP_ERROR_NO_ERROR;
3163 /* Verify the ASCONF packet before we process it. */
3164 bool sctp_verify_asconf(const struct sctp_association *asoc,
3165 struct sctp_chunk *chunk, bool addr_param_needed,
3166 struct sctp_paramhdr **errp)
3168 sctp_addip_chunk_t *addip = (sctp_addip_chunk_t *) chunk->chunk_hdr;
3169 union sctp_params param;
3170 bool addr_param_seen = false;
3172 sctp_walk_params(param, addip, addip_hdr.params) {
3173 size_t length = ntohs(param.p->length);
3176 switch (param.p->type) {
3177 case SCTP_PARAM_ERR_CAUSE:
3179 case SCTP_PARAM_IPV4_ADDRESS:
3180 if (length != sizeof(sctp_ipv4addr_param_t))
3182 /* ensure there is only one addr param and it's in the
3183 * beginning of addip_hdr params, or we reject it.
3185 if (param.v != addip->addip_hdr.params)
3187 addr_param_seen = true;
3189 case SCTP_PARAM_IPV6_ADDRESS:
3190 if (length != sizeof(sctp_ipv6addr_param_t))
3192 if (param.v != addip->addip_hdr.params)
3194 addr_param_seen = true;
3196 case SCTP_PARAM_ADD_IP:
3197 case SCTP_PARAM_DEL_IP:
3198 case SCTP_PARAM_SET_PRIMARY:
3199 /* In ASCONF chunks, these need to be first. */
3200 if (addr_param_needed && !addr_param_seen)
3202 length = ntohs(param.addip->param_hdr.length);
3203 if (length < sizeof(sctp_addip_param_t) +
3204 sizeof(sctp_paramhdr_t))
3207 case SCTP_PARAM_SUCCESS_REPORT:
3208 case SCTP_PARAM_ADAPTATION_LAYER_IND:
3209 if (length != sizeof(sctp_addip_param_t))
3213 /* This is unkown to us, reject! */
3218 /* Remaining sanity checks. */
3219 if (addr_param_needed && !addr_param_seen)
3221 if (!addr_param_needed && addr_param_seen)
3223 if (param.v != chunk->chunk_end)
3229 /* Process an incoming ASCONF chunk with the next expected serial no. and
3230 * return an ASCONF_ACK chunk to be sent in response.
3232 struct sctp_chunk *sctp_process_asconf(struct sctp_association *asoc,
3233 struct sctp_chunk *asconf)
3235 sctp_addip_chunk_t *addip = (sctp_addip_chunk_t *) asconf->chunk_hdr;
3236 bool all_param_pass = true;
3237 union sctp_params param;
3238 sctp_addiphdr_t *hdr;
3239 union sctp_addr_param *addr_param;
3240 sctp_addip_param_t *asconf_param;
3241 struct sctp_chunk *asconf_ack;
3247 chunk_len = ntohs(asconf->chunk_hdr->length) - sizeof(sctp_chunkhdr_t);
3248 hdr = (sctp_addiphdr_t *)asconf->skb->data;
3249 serial = ntohl(hdr->serial);
3251 /* Skip the addiphdr and store a pointer to address parameter. */
3252 length = sizeof(sctp_addiphdr_t);
3253 addr_param = (union sctp_addr_param *)(asconf->skb->data + length);
3254 chunk_len -= length;
3256 /* Skip the address parameter and store a pointer to the first
3259 length = ntohs(addr_param->p.length);
3260 asconf_param = (void *)addr_param + length;
3261 chunk_len -= length;
3263 /* create an ASCONF_ACK chunk.
3264 * Based on the definitions of parameters, we know that the size of
3265 * ASCONF_ACK parameters are less than or equal to the fourfold of ASCONF
3268 asconf_ack = sctp_make_asconf_ack(asoc, serial, chunk_len * 4);
3272 /* Process the TLVs contained within the ASCONF chunk. */
3273 sctp_walk_params(param, addip, addip_hdr.params) {
3274 /* Skip preceeding address parameters. */
3275 if (param.p->type == SCTP_PARAM_IPV4_ADDRESS ||
3276 param.p->type == SCTP_PARAM_IPV6_ADDRESS)
3279 err_code = sctp_process_asconf_param(asoc, asconf,
3282 * If an error response is received for a TLV parameter,
3283 * all TLVs with no response before the failed TLV are
3284 * considered successful if not reported. All TLVs after
3285 * the failed response are considered unsuccessful unless
3286 * a specific success indication is present for the parameter.
3288 if (err_code != SCTP_ERROR_NO_ERROR)
3289 all_param_pass = false;
3290 if (!all_param_pass)
3291 sctp_add_asconf_response(asconf_ack, param.addip->crr_id,
3292 err_code, param.addip);
3294 /* ADDIP 4.3 D11) When an endpoint receiving an ASCONF to add
3295 * an IP address sends an 'Out of Resource' in its response, it
3296 * MUST also fail any subsequent add or delete requests bundled
3299 if (err_code == SCTP_ERROR_RSRC_LOW)
3303 asoc->peer.addip_serial++;
3305 /* If we are sending a new ASCONF_ACK hold a reference to it in assoc
3306 * after freeing the reference to old asconf ack if any.
3309 sctp_chunk_hold(asconf_ack);
3310 list_add_tail(&asconf_ack->transmitted_list,
3311 &asoc->asconf_ack_list);
3317 /* Process a asconf parameter that is successfully acked. */
3318 static void sctp_asconf_param_success(struct sctp_association *asoc,
3319 sctp_addip_param_t *asconf_param)
3322 union sctp_addr addr;
3323 struct sctp_bind_addr *bp = &asoc->base.bind_addr;
3324 union sctp_addr_param *addr_param;
3325 struct sctp_transport *transport;
3326 struct sctp_sockaddr_entry *saddr;
3328 addr_param = (void *)asconf_param + sizeof(sctp_addip_param_t);
3330 /* We have checked the packet before, so we do not check again. */
3331 af = sctp_get_af_specific(param_type2af(addr_param->p.type));
3332 af->from_addr_param(&addr, addr_param, htons(bp->port), 0);
3334 switch (asconf_param->param_hdr.type) {
3335 case SCTP_PARAM_ADD_IP:
3336 /* This is always done in BH context with a socket lock
3337 * held, so the list can not change.
3340 list_for_each_entry(saddr, &bp->address_list, list) {
3341 if (sctp_cmp_addr_exact(&saddr->a, &addr))
3342 saddr->state = SCTP_ADDR_SRC;
3345 list_for_each_entry(transport, &asoc->peer.transport_addr_list,
3347 dst_release(transport->dst);
3348 transport->dst = NULL;
3351 case SCTP_PARAM_DEL_IP:
3353 sctp_del_bind_addr(bp, &addr);
3354 if (asoc->asconf_addr_del_pending != NULL &&
3355 sctp_cmp_addr_exact(asoc->asconf_addr_del_pending, &addr)) {
3356 kfree(asoc->asconf_addr_del_pending);
3357 asoc->asconf_addr_del_pending = NULL;
3360 list_for_each_entry(transport, &asoc->peer.transport_addr_list,
3362 dst_release(transport->dst);
3363 transport->dst = NULL;
3371 /* Get the corresponding ASCONF response error code from the ASCONF_ACK chunk
3372 * for the given asconf parameter. If there is no response for this parameter,
3373 * return the error code based on the third argument 'no_err'.
3375 * A7) If an error response is received for a TLV parameter, all TLVs with no
3376 * response before the failed TLV are considered successful if not reported.
3377 * All TLVs after the failed response are considered unsuccessful unless a
3378 * specific success indication is present for the parameter.
3380 static __be16 sctp_get_asconf_response(struct sctp_chunk *asconf_ack,
3381 sctp_addip_param_t *asconf_param,
3384 sctp_addip_param_t *asconf_ack_param;
3385 sctp_errhdr_t *err_param;
3391 err_code = SCTP_ERROR_NO_ERROR;
3393 err_code = SCTP_ERROR_REQ_REFUSED;
3395 asconf_ack_len = ntohs(asconf_ack->chunk_hdr->length) -
3396 sizeof(sctp_chunkhdr_t);
3398 /* Skip the addiphdr from the asconf_ack chunk and store a pointer to
3399 * the first asconf_ack parameter.
3401 length = sizeof(sctp_addiphdr_t);
3402 asconf_ack_param = (sctp_addip_param_t *)(asconf_ack->skb->data +
3404 asconf_ack_len -= length;
3406 while (asconf_ack_len > 0) {
3407 if (asconf_ack_param->crr_id == asconf_param->crr_id) {
3408 switch (asconf_ack_param->param_hdr.type) {
3409 case SCTP_PARAM_SUCCESS_REPORT:
3410 return SCTP_ERROR_NO_ERROR;
3411 case SCTP_PARAM_ERR_CAUSE:
3412 length = sizeof(sctp_addip_param_t);
3413 err_param = (void *)asconf_ack_param + length;
3414 asconf_ack_len -= length;
3415 if (asconf_ack_len > 0)
3416 return err_param->cause;
3418 return SCTP_ERROR_INV_PARAM;
3421 return SCTP_ERROR_INV_PARAM;
3425 length = ntohs(asconf_ack_param->param_hdr.length);
3426 asconf_ack_param = (void *)asconf_ack_param + length;
3427 asconf_ack_len -= length;
3433 /* Process an incoming ASCONF_ACK chunk against the cached last ASCONF chunk. */
3434 int sctp_process_asconf_ack(struct sctp_association *asoc,
3435 struct sctp_chunk *asconf_ack)
3437 struct sctp_chunk *asconf = asoc->addip_last_asconf;
3438 union sctp_addr_param *addr_param;
3439 sctp_addip_param_t *asconf_param;
3441 int asconf_len = asconf->skb->len;
3442 int all_param_pass = 0;
3445 __be16 err_code = SCTP_ERROR_NO_ERROR;
3447 /* Skip the chunkhdr and addiphdr from the last asconf sent and store
3448 * a pointer to address parameter.
3450 length = sizeof(sctp_addip_chunk_t);
3451 addr_param = (union sctp_addr_param *)(asconf->skb->data + length);
3452 asconf_len -= length;
3454 /* Skip the address parameter in the last asconf sent and store a
3455 * pointer to the first asconf parameter.
3457 length = ntohs(addr_param->p.length);
3458 asconf_param = (void *)addr_param + length;
3459 asconf_len -= length;
3462 * A8) If there is no response(s) to specific TLV parameter(s), and no
3463 * failures are indicated, then all request(s) are considered
3466 if (asconf_ack->skb->len == sizeof(sctp_addiphdr_t))
3469 /* Process the TLVs contained in the last sent ASCONF chunk. */
3470 while (asconf_len > 0) {
3472 err_code = SCTP_ERROR_NO_ERROR;
3474 err_code = sctp_get_asconf_response(asconf_ack,
3477 if (no_err && (SCTP_ERROR_NO_ERROR != err_code))
3482 case SCTP_ERROR_NO_ERROR:
3483 sctp_asconf_param_success(asoc, asconf_param);
3486 case SCTP_ERROR_RSRC_LOW:
3490 case SCTP_ERROR_UNKNOWN_PARAM:
3491 /* Disable sending this type of asconf parameter in
3494 asoc->peer.addip_disabled_mask |=
3495 asconf_param->param_hdr.type;
3498 case SCTP_ERROR_REQ_REFUSED:
3499 case SCTP_ERROR_DEL_LAST_IP:
3500 case SCTP_ERROR_DEL_SRC_IP:
3505 /* Skip the processed asconf parameter and move to the next
3508 length = ntohs(asconf_param->param_hdr.length);
3509 asconf_param = (void *)asconf_param + length;
3510 asconf_len -= length;
3513 if (no_err && asoc->src_out_of_asoc_ok) {
3514 asoc->src_out_of_asoc_ok = 0;
3515 sctp_transport_immediate_rtx(asoc->peer.primary_path);
3518 /* Free the cached last sent asconf chunk. */
3519 list_del_init(&asconf->transmitted_list);
3520 sctp_chunk_free(asconf);
3521 asoc->addip_last_asconf = NULL;
3526 /* Make a FWD TSN chunk. */
3527 struct sctp_chunk *sctp_make_fwdtsn(const struct sctp_association *asoc,
3528 __u32 new_cum_tsn, size_t nstreams,
3529 struct sctp_fwdtsn_skip *skiplist)
3531 struct sctp_chunk *retval = NULL;
3532 struct sctp_fwdtsn_hdr ftsn_hdr;
3533 struct sctp_fwdtsn_skip skip;
3537 hint = (nstreams + 1) * sizeof(__u32);
3539 retval = sctp_make_control(asoc, SCTP_CID_FWD_TSN, 0, hint, GFP_ATOMIC);
3544 ftsn_hdr.new_cum_tsn = htonl(new_cum_tsn);
3545 retval->subh.fwdtsn_hdr =
3546 sctp_addto_chunk(retval, sizeof(ftsn_hdr), &ftsn_hdr);
3548 for (i = 0; i < nstreams; i++) {
3549 skip.stream = skiplist[i].stream;
3550 skip.ssn = skiplist[i].ssn;
3551 sctp_addto_chunk(retval, sizeof(skip), &skip);