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 chunk->prsctp_param = sinfo->sinfo_timetolive;
727 /* Make a DATA chunk for the given association from the provided
728 * parameters. However, do not populate the data payload.
730 struct sctp_chunk *sctp_make_datafrag_empty(struct sctp_association *asoc,
731 const struct sctp_sndrcvinfo *sinfo,
732 int data_len, __u8 flags, __u16 ssn,
735 struct sctp_chunk *retval;
736 struct sctp_datahdr dp;
739 /* We assign the TSN as LATE as possible, not here when
740 * creating the chunk.
743 dp.stream = htons(sinfo->sinfo_stream);
744 dp.ppid = sinfo->sinfo_ppid;
746 /* Set the flags for an unordered send. */
747 if (sinfo->sinfo_flags & SCTP_UNORDERED) {
748 flags |= SCTP_DATA_UNORDERED;
753 chunk_len = sizeof(dp) + data_len;
754 retval = sctp_make_data(asoc, flags, chunk_len, gfp);
758 retval->subh.data_hdr = sctp_addto_chunk(retval, sizeof(dp), &dp);
759 memcpy(&retval->sinfo, sinfo, sizeof(struct sctp_sndrcvinfo));
760 sctp_set_prsctp_policy(retval, sinfo);
766 /* Create a selective ackowledgement (SACK) for the given
767 * association. This reports on which TSN's we've seen to date,
768 * including duplicates and gaps.
770 struct sctp_chunk *sctp_make_sack(const struct sctp_association *asoc)
772 struct sctp_chunk *retval;
773 struct sctp_sackhdr sack;
776 __u16 num_gabs, num_dup_tsns;
777 struct sctp_association *aptr = (struct sctp_association *)asoc;
778 struct sctp_tsnmap *map = (struct sctp_tsnmap *)&asoc->peer.tsn_map;
779 struct sctp_gap_ack_block gabs[SCTP_MAX_GABS];
780 struct sctp_transport *trans;
782 memset(gabs, 0, sizeof(gabs));
783 ctsn = sctp_tsnmap_get_ctsn(map);
785 pr_debug("%s: sackCTSNAck sent:0x%x\n", __func__, ctsn);
787 /* How much room is needed in the chunk? */
788 num_gabs = sctp_tsnmap_num_gabs(map, gabs);
789 num_dup_tsns = sctp_tsnmap_num_dups(map);
791 /* Initialize the SACK header. */
792 sack.cum_tsn_ack = htonl(ctsn);
793 sack.a_rwnd = htonl(asoc->a_rwnd);
794 sack.num_gap_ack_blocks = htons(num_gabs);
795 sack.num_dup_tsns = htons(num_dup_tsns);
798 + sizeof(struct sctp_gap_ack_block) * num_gabs
799 + sizeof(__u32) * num_dup_tsns;
801 /* Create the chunk. */
802 retval = sctp_make_control(asoc, SCTP_CID_SACK, 0, len, GFP_ATOMIC);
806 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
808 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
809 * HEARTBEAT ACK, etc.) to the same destination transport
810 * address from which it received the DATA or control chunk to
811 * which it is replying. This rule should also be followed if
812 * the endpoint is bundling DATA chunks together with the
815 * However, when acknowledging multiple DATA chunks received
816 * in packets from different source addresses in a single
817 * SACK, the SACK chunk may be transmitted to one of the
818 * destination transport addresses from which the DATA or
819 * control chunks being acknowledged were received.
821 * [BUG: We do not implement the following paragraph.
822 * Perhaps we should remember the last transport we used for a
823 * SACK and avoid that (if possible) if we have seen any
824 * duplicates. --piggy]
826 * When a receiver of a duplicate DATA chunk sends a SACK to a
827 * multi- homed endpoint it MAY be beneficial to vary the
828 * destination address and not use the source address of the
829 * DATA chunk. The reason being that receiving a duplicate
830 * from a multi-homed endpoint might indicate that the return
831 * path (as specified in the source address of the DATA chunk)
832 * for the SACK is broken.
834 * [Send to the address from which we last received a DATA chunk.]
836 retval->transport = asoc->peer.last_data_from;
838 retval->subh.sack_hdr =
839 sctp_addto_chunk(retval, sizeof(sack), &sack);
841 /* Add the gap ack block information. */
843 sctp_addto_chunk(retval, sizeof(__u32) * num_gabs,
846 /* Add the duplicate TSN information. */
848 aptr->stats.idupchunks += num_dup_tsns;
849 sctp_addto_chunk(retval, sizeof(__u32) * num_dup_tsns,
850 sctp_tsnmap_get_dups(map));
852 /* Once we have a sack generated, check to see what our sack
853 * generation is, if its 0, reset the transports to 0, and reset
854 * the association generation to 1
856 * The idea is that zero is never used as a valid generation for the
857 * association so no transport will match after a wrap event like this,
858 * Until the next sack
860 if (++aptr->peer.sack_generation == 0) {
861 list_for_each_entry(trans, &asoc->peer.transport_addr_list,
863 trans->sack_generation = 0;
864 aptr->peer.sack_generation = 1;
870 /* Make a SHUTDOWN chunk. */
871 struct sctp_chunk *sctp_make_shutdown(const struct sctp_association *asoc,
872 const struct sctp_chunk *chunk)
874 struct sctp_chunk *retval;
875 sctp_shutdownhdr_t shut;
878 ctsn = sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map);
879 shut.cum_tsn_ack = htonl(ctsn);
881 retval = sctp_make_control(asoc, SCTP_CID_SHUTDOWN, 0,
882 sizeof(sctp_shutdownhdr_t), GFP_ATOMIC);
886 retval->subh.shutdown_hdr =
887 sctp_addto_chunk(retval, sizeof(shut), &shut);
890 retval->transport = chunk->transport;
895 struct sctp_chunk *sctp_make_shutdown_ack(const struct sctp_association *asoc,
896 const struct sctp_chunk *chunk)
898 struct sctp_chunk *retval;
900 retval = sctp_make_control(asoc, SCTP_CID_SHUTDOWN_ACK, 0, 0,
903 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
905 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
906 * HEARTBEAT ACK, * etc.) to the same destination transport
907 * address from which it * received the DATA or control chunk
908 * to which it is replying.
910 * [ACK back to where the SHUTDOWN came from.]
913 retval->transport = chunk->transport;
918 struct sctp_chunk *sctp_make_shutdown_complete(
919 const struct sctp_association *asoc,
920 const struct sctp_chunk *chunk)
922 struct sctp_chunk *retval;
925 /* Set the T-bit if we have no association (vtag will be
928 flags |= asoc ? 0 : SCTP_CHUNK_FLAG_T;
930 retval = sctp_make_control(asoc, SCTP_CID_SHUTDOWN_COMPLETE, flags,
933 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
935 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
936 * HEARTBEAT ACK, * etc.) to the same destination transport
937 * address from which it * received the DATA or control chunk
938 * to which it is replying.
940 * [Report SHUTDOWN COMPLETE back to where the SHUTDOWN ACK
944 retval->transport = chunk->transport;
949 /* Create an ABORT. Note that we set the T bit if we have no
950 * association, except when responding to an INIT (sctpimpguide 2.41).
952 struct sctp_chunk *sctp_make_abort(const struct sctp_association *asoc,
953 const struct sctp_chunk *chunk,
956 struct sctp_chunk *retval;
959 /* Set the T-bit if we have no association and 'chunk' is not
960 * an INIT (vtag will be reflected).
963 if (chunk && chunk->chunk_hdr &&
964 chunk->chunk_hdr->type == SCTP_CID_INIT)
967 flags = SCTP_CHUNK_FLAG_T;
970 retval = sctp_make_control(asoc, SCTP_CID_ABORT, flags, hint,
973 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
975 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
976 * HEARTBEAT ACK, * etc.) to the same destination transport
977 * address from which it * received the DATA or control chunk
978 * to which it is replying.
980 * [ABORT back to where the offender came from.]
983 retval->transport = chunk->transport;
988 /* Helper to create ABORT with a NO_USER_DATA error. */
989 struct sctp_chunk *sctp_make_abort_no_data(
990 const struct sctp_association *asoc,
991 const struct sctp_chunk *chunk, __u32 tsn)
993 struct sctp_chunk *retval;
996 retval = sctp_make_abort(asoc, chunk, sizeof(sctp_errhdr_t)
1002 /* Put the tsn back into network byte order. */
1003 payload = htonl(tsn);
1004 sctp_init_cause(retval, SCTP_ERROR_NO_DATA, sizeof(payload));
1005 sctp_addto_chunk(retval, sizeof(payload), (const void *)&payload);
1007 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
1009 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
1010 * HEARTBEAT ACK, * etc.) to the same destination transport
1011 * address from which it * received the DATA or control chunk
1012 * to which it is replying.
1014 * [ABORT back to where the offender came from.]
1017 retval->transport = chunk->transport;
1023 /* Helper to create ABORT with a SCTP_ERROR_USER_ABORT error. */
1024 struct sctp_chunk *sctp_make_abort_user(const struct sctp_association *asoc,
1028 struct sctp_chunk *retval;
1029 void *payload = NULL;
1032 retval = sctp_make_abort(asoc, NULL, sizeof(sctp_errhdr_t) + paylen);
1037 /* Put the msg_iov together into payload. */
1038 payload = kmalloc(paylen, GFP_KERNEL);
1042 err = memcpy_from_msg(payload, msg, paylen);
1047 sctp_init_cause(retval, SCTP_ERROR_USER_ABORT, paylen);
1048 sctp_addto_chunk(retval, paylen, payload);
1058 sctp_chunk_free(retval);
1064 /* Append bytes to the end of a parameter. Will panic if chunk is not big
1067 static void *sctp_addto_param(struct sctp_chunk *chunk, int len,
1071 int chunklen = ntohs(chunk->chunk_hdr->length);
1073 target = skb_put(chunk->skb, len);
1076 memcpy(target, data, len);
1078 memset(target, 0, len);
1080 /* Adjust the chunk length field. */
1081 chunk->chunk_hdr->length = htons(chunklen + len);
1082 chunk->chunk_end = skb_tail_pointer(chunk->skb);
1087 /* Make an ABORT chunk with a PROTOCOL VIOLATION cause code. */
1088 struct sctp_chunk *sctp_make_abort_violation(
1089 const struct sctp_association *asoc,
1090 const struct sctp_chunk *chunk,
1091 const __u8 *payload,
1092 const size_t paylen)
1094 struct sctp_chunk *retval;
1095 struct sctp_paramhdr phdr;
1097 retval = sctp_make_abort(asoc, chunk, sizeof(sctp_errhdr_t) + paylen
1098 + sizeof(sctp_paramhdr_t));
1102 sctp_init_cause(retval, SCTP_ERROR_PROTO_VIOLATION, paylen
1103 + sizeof(sctp_paramhdr_t));
1105 phdr.type = htons(chunk->chunk_hdr->type);
1106 phdr.length = chunk->chunk_hdr->length;
1107 sctp_addto_chunk(retval, paylen, payload);
1108 sctp_addto_param(retval, sizeof(sctp_paramhdr_t), &phdr);
1114 struct sctp_chunk *sctp_make_violation_paramlen(
1115 const struct sctp_association *asoc,
1116 const struct sctp_chunk *chunk,
1117 struct sctp_paramhdr *param)
1119 struct sctp_chunk *retval;
1120 static const char error[] = "The following parameter had invalid length:";
1121 size_t payload_len = sizeof(error) + sizeof(sctp_errhdr_t) +
1122 sizeof(sctp_paramhdr_t);
1124 retval = sctp_make_abort(asoc, chunk, payload_len);
1128 sctp_init_cause(retval, SCTP_ERROR_PROTO_VIOLATION,
1129 sizeof(error) + sizeof(sctp_paramhdr_t));
1130 sctp_addto_chunk(retval, sizeof(error), error);
1131 sctp_addto_param(retval, sizeof(sctp_paramhdr_t), param);
1137 struct sctp_chunk *sctp_make_violation_max_retrans(
1138 const struct sctp_association *asoc,
1139 const struct sctp_chunk *chunk)
1141 struct sctp_chunk *retval;
1142 static const char error[] = "Association exceeded its max_retans count";
1143 size_t payload_len = sizeof(error) + sizeof(sctp_errhdr_t);
1145 retval = sctp_make_abort(asoc, chunk, payload_len);
1149 sctp_init_cause(retval, SCTP_ERROR_PROTO_VIOLATION, sizeof(error));
1150 sctp_addto_chunk(retval, sizeof(error), error);
1156 /* Make a HEARTBEAT chunk. */
1157 struct sctp_chunk *sctp_make_heartbeat(const struct sctp_association *asoc,
1158 const struct sctp_transport *transport)
1160 struct sctp_chunk *retval;
1161 sctp_sender_hb_info_t hbinfo;
1163 retval = sctp_make_control(asoc, SCTP_CID_HEARTBEAT, 0,
1164 sizeof(hbinfo), GFP_ATOMIC);
1169 hbinfo.param_hdr.type = SCTP_PARAM_HEARTBEAT_INFO;
1170 hbinfo.param_hdr.length = htons(sizeof(sctp_sender_hb_info_t));
1171 hbinfo.daddr = transport->ipaddr;
1172 hbinfo.sent_at = jiffies;
1173 hbinfo.hb_nonce = transport->hb_nonce;
1175 /* Cast away the 'const', as this is just telling the chunk
1176 * what transport it belongs to.
1178 retval->transport = (struct sctp_transport *) transport;
1179 retval->subh.hbs_hdr = sctp_addto_chunk(retval, sizeof(hbinfo),
1186 struct sctp_chunk *sctp_make_heartbeat_ack(const struct sctp_association *asoc,
1187 const struct sctp_chunk *chunk,
1188 const void *payload, const size_t paylen)
1190 struct sctp_chunk *retval;
1192 retval = sctp_make_control(asoc, SCTP_CID_HEARTBEAT_ACK, 0, paylen,
1197 retval->subh.hbs_hdr = sctp_addto_chunk(retval, paylen, payload);
1199 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
1201 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
1202 * HEARTBEAT ACK, * etc.) to the same destination transport
1203 * address from which it * received the DATA or control chunk
1204 * to which it is replying.
1206 * [HBACK back to where the HEARTBEAT came from.]
1209 retval->transport = chunk->transport;
1215 /* Create an Operation Error chunk with the specified space reserved.
1216 * This routine can be used for containing multiple causes in the chunk.
1218 static struct sctp_chunk *sctp_make_op_error_space(
1219 const struct sctp_association *asoc,
1220 const struct sctp_chunk *chunk,
1223 struct sctp_chunk *retval;
1225 retval = sctp_make_control(asoc, SCTP_CID_ERROR, 0,
1226 sizeof(sctp_errhdr_t) + size, GFP_ATOMIC);
1230 /* RFC 2960 6.4 Multi-homed SCTP Endpoints
1232 * An endpoint SHOULD transmit reply chunks (e.g., SACK,
1233 * HEARTBEAT ACK, etc.) to the same destination transport
1234 * address from which it received the DATA or control chunk
1235 * to which it is replying.
1239 retval->transport = chunk->transport;
1245 /* Create an Operation Error chunk of a fixed size,
1246 * specifically, max(asoc->pathmtu, SCTP_DEFAULT_MAXSEGMENT)
1247 * This is a helper function to allocate an error chunk for
1248 * for those invalid parameter codes in which we may not want
1249 * to report all the errors, if the incoming chunk is large
1251 static inline struct sctp_chunk *sctp_make_op_error_fixed(
1252 const struct sctp_association *asoc,
1253 const struct sctp_chunk *chunk)
1255 size_t size = asoc ? asoc->pathmtu : 0;
1258 size = SCTP_DEFAULT_MAXSEGMENT;
1260 return sctp_make_op_error_space(asoc, chunk, size);
1263 /* Create an Operation Error chunk. */
1264 struct sctp_chunk *sctp_make_op_error(const struct sctp_association *asoc,
1265 const struct sctp_chunk *chunk,
1266 __be16 cause_code, const void *payload,
1267 size_t paylen, size_t reserve_tail)
1269 struct sctp_chunk *retval;
1271 retval = sctp_make_op_error_space(asoc, chunk, paylen + reserve_tail);
1275 sctp_init_cause(retval, cause_code, paylen + reserve_tail);
1276 sctp_addto_chunk(retval, paylen, payload);
1278 sctp_addto_param(retval, reserve_tail, NULL);
1284 struct sctp_chunk *sctp_make_auth(const struct sctp_association *asoc)
1286 struct sctp_chunk *retval;
1287 struct sctp_hmac *hmac_desc;
1288 struct sctp_authhdr auth_hdr;
1291 /* Get the first hmac that the peer told us to use */
1292 hmac_desc = sctp_auth_asoc_get_hmac(asoc);
1293 if (unlikely(!hmac_desc))
1296 retval = sctp_make_control(asoc, SCTP_CID_AUTH, 0,
1297 hmac_desc->hmac_len + sizeof(sctp_authhdr_t),
1302 auth_hdr.hmac_id = htons(hmac_desc->hmac_id);
1303 auth_hdr.shkey_id = htons(asoc->active_key_id);
1305 retval->subh.auth_hdr = sctp_addto_chunk(retval, sizeof(sctp_authhdr_t),
1308 hmac = skb_put(retval->skb, hmac_desc->hmac_len);
1309 memset(hmac, 0, hmac_desc->hmac_len);
1311 /* Adjust the chunk header to include the empty MAC */
1312 retval->chunk_hdr->length =
1313 htons(ntohs(retval->chunk_hdr->length) + hmac_desc->hmac_len);
1314 retval->chunk_end = skb_tail_pointer(retval->skb);
1320 /********************************************************************
1321 * 2nd Level Abstractions
1322 ********************************************************************/
1324 /* Turn an skb into a chunk.
1325 * FIXME: Eventually move the structure directly inside the skb->cb[].
1327 * sctpimpguide-05.txt Section 2.8.2
1328 * M1) Each time a new DATA chunk is transmitted
1329 * set the 'TSN.Missing.Report' count for that TSN to 0. The
1330 * 'TSN.Missing.Report' count will be used to determine missing chunks
1331 * and when to fast retransmit.
1334 struct sctp_chunk *sctp_chunkify(struct sk_buff *skb,
1335 const struct sctp_association *asoc,
1336 struct sock *sk, gfp_t gfp)
1338 struct sctp_chunk *retval;
1340 retval = kmem_cache_zalloc(sctp_chunk_cachep, gfp);
1345 pr_debug("%s: chunkifying skb:%p w/o an sk\n", __func__, skb);
1347 INIT_LIST_HEAD(&retval->list);
1349 retval->asoc = (struct sctp_association *)asoc;
1350 retval->singleton = 1;
1352 retval->fast_retransmit = SCTP_CAN_FRTX;
1354 /* Polish the bead hole. */
1355 INIT_LIST_HEAD(&retval->transmitted_list);
1356 INIT_LIST_HEAD(&retval->frag_list);
1357 SCTP_DBG_OBJCNT_INC(chunk);
1358 atomic_set(&retval->refcnt, 1);
1364 /* Set chunk->source and dest based on the IP header in chunk->skb. */
1365 void sctp_init_addrs(struct sctp_chunk *chunk, union sctp_addr *src,
1366 union sctp_addr *dest)
1368 memcpy(&chunk->source, src, sizeof(union sctp_addr));
1369 memcpy(&chunk->dest, dest, sizeof(union sctp_addr));
1372 /* Extract the source address from a chunk. */
1373 const union sctp_addr *sctp_source(const struct sctp_chunk *chunk)
1375 /* If we have a known transport, use that. */
1376 if (chunk->transport) {
1377 return &chunk->transport->ipaddr;
1379 /* Otherwise, extract it from the IP header. */
1380 return &chunk->source;
1384 /* Create a new chunk, setting the type and flags headers from the
1385 * arguments, reserving enough space for a 'paylen' byte payload.
1387 static struct sctp_chunk *_sctp_make_chunk(const struct sctp_association *asoc,
1388 __u8 type, __u8 flags, int paylen,
1391 struct sctp_chunk *retval;
1392 sctp_chunkhdr_t *chunk_hdr;
1393 struct sk_buff *skb;
1396 /* No need to allocate LL here, as this is only a chunk. */
1397 skb = alloc_skb(WORD_ROUND(sizeof(sctp_chunkhdr_t) + paylen), gfp);
1401 /* Make room for the chunk header. */
1402 chunk_hdr = (sctp_chunkhdr_t *)skb_put(skb, sizeof(sctp_chunkhdr_t));
1403 chunk_hdr->type = type;
1404 chunk_hdr->flags = flags;
1405 chunk_hdr->length = htons(sizeof(sctp_chunkhdr_t));
1407 sk = asoc ? asoc->base.sk : NULL;
1408 retval = sctp_chunkify(skb, asoc, sk, gfp);
1414 retval->chunk_hdr = chunk_hdr;
1415 retval->chunk_end = ((__u8 *)chunk_hdr) + sizeof(struct sctp_chunkhdr);
1417 /* Determine if the chunk needs to be authenticated */
1418 if (sctp_auth_send_cid(type, asoc))
1426 static struct sctp_chunk *sctp_make_data(const struct sctp_association *asoc,
1427 __u8 flags, int paylen, gfp_t gfp)
1429 return _sctp_make_chunk(asoc, SCTP_CID_DATA, flags, paylen, gfp);
1432 static struct sctp_chunk *sctp_make_control(const struct sctp_association *asoc,
1433 __u8 type, __u8 flags, int paylen,
1436 struct sctp_chunk *chunk;
1438 chunk = _sctp_make_chunk(asoc, type, flags, paylen, gfp);
1440 sctp_control_set_owner_w(chunk);
1445 /* Release the memory occupied by a chunk. */
1446 static void sctp_chunk_destroy(struct sctp_chunk *chunk)
1448 BUG_ON(!list_empty(&chunk->list));
1449 list_del_init(&chunk->transmitted_list);
1451 consume_skb(chunk->skb);
1452 consume_skb(chunk->auth_chunk);
1454 SCTP_DBG_OBJCNT_DEC(chunk);
1455 kmem_cache_free(sctp_chunk_cachep, chunk);
1458 /* Possibly, free the chunk. */
1459 void sctp_chunk_free(struct sctp_chunk *chunk)
1461 /* Release our reference on the message tracker. */
1463 sctp_datamsg_put(chunk->msg);
1465 sctp_chunk_put(chunk);
1468 /* Grab a reference to the chunk. */
1469 void sctp_chunk_hold(struct sctp_chunk *ch)
1471 atomic_inc(&ch->refcnt);
1474 /* Release a reference to the chunk. */
1475 void sctp_chunk_put(struct sctp_chunk *ch)
1477 if (atomic_dec_and_test(&ch->refcnt))
1478 sctp_chunk_destroy(ch);
1481 /* Append bytes to the end of a chunk. Will panic if chunk is not big
1484 void *sctp_addto_chunk(struct sctp_chunk *chunk, int len, const void *data)
1488 int chunklen = ntohs(chunk->chunk_hdr->length);
1489 int padlen = WORD_ROUND(chunklen) - chunklen;
1491 padding = skb_put(chunk->skb, padlen);
1492 target = skb_put(chunk->skb, len);
1494 memset(padding, 0, padlen);
1495 memcpy(target, data, len);
1497 /* Adjust the chunk length field. */
1498 chunk->chunk_hdr->length = htons(chunklen + padlen + len);
1499 chunk->chunk_end = skb_tail_pointer(chunk->skb);
1504 /* Append bytes to the end of a chunk. Returns NULL if there isn't sufficient
1505 * space in the chunk
1507 static void *sctp_addto_chunk_fixed(struct sctp_chunk *chunk,
1508 int len, const void *data)
1510 if (skb_tailroom(chunk->skb) >= len)
1511 return sctp_addto_chunk(chunk, len, data);
1516 /* Append bytes from user space to the end of a chunk. Will panic if
1517 * chunk is not big enough.
1518 * Returns a kernel err value.
1520 int sctp_user_addto_chunk(struct sctp_chunk *chunk, int len,
1521 struct iov_iter *from)
1526 /* Make room in chunk for data. */
1527 target = skb_put(chunk->skb, len);
1529 /* Copy data (whole iovec) into chunk */
1530 copied = copy_from_iter(target, len, from);
1534 /* Adjust the chunk length field. */
1535 chunk->chunk_hdr->length =
1536 htons(ntohs(chunk->chunk_hdr->length) + len);
1537 chunk->chunk_end = skb_tail_pointer(chunk->skb);
1542 /* Helper function to assign a TSN if needed. This assumes that both
1543 * the data_hdr and association have already been assigned.
1545 void sctp_chunk_assign_ssn(struct sctp_chunk *chunk)
1547 struct sctp_datamsg *msg;
1548 struct sctp_chunk *lchunk;
1549 struct sctp_stream *stream;
1556 /* All fragments will be on the same stream */
1557 sid = ntohs(chunk->subh.data_hdr->stream);
1558 stream = &chunk->asoc->ssnmap->out;
1560 /* Now assign the sequence number to the entire message.
1561 * All fragments must have the same stream sequence number.
1564 list_for_each_entry(lchunk, &msg->chunks, frag_list) {
1565 if (lchunk->chunk_hdr->flags & SCTP_DATA_UNORDERED) {
1568 if (lchunk->chunk_hdr->flags & SCTP_DATA_LAST_FRAG)
1569 ssn = sctp_ssn_next(stream, sid);
1571 ssn = sctp_ssn_peek(stream, sid);
1574 lchunk->subh.data_hdr->ssn = htons(ssn);
1575 lchunk->has_ssn = 1;
1579 /* Helper function to assign a TSN if needed. This assumes that both
1580 * the data_hdr and association have already been assigned.
1582 void sctp_chunk_assign_tsn(struct sctp_chunk *chunk)
1584 if (!chunk->has_tsn) {
1585 /* This is the last possible instant to
1588 chunk->subh.data_hdr->tsn =
1589 htonl(sctp_association_get_next_tsn(chunk->asoc));
1594 /* Create a CLOSED association to use with an incoming packet. */
1595 struct sctp_association *sctp_make_temp_asoc(const struct sctp_endpoint *ep,
1596 struct sctp_chunk *chunk,
1599 struct sctp_association *asoc;
1600 struct sk_buff *skb;
1604 /* Create the bare association. */
1605 scope = sctp_scope(sctp_source(chunk));
1606 asoc = sctp_association_new(ep, ep->base.sk, scope, gfp);
1611 /* Create an entry for the source address of the packet. */
1612 af = sctp_get_af_specific(ipver2af(ip_hdr(skb)->version));
1615 af->from_skb(&asoc->c.peer_addr, skb, 1);
1620 sctp_association_free(asoc);
1624 /* Build a cookie representing asoc.
1625 * This INCLUDES the param header needed to put the cookie in the INIT ACK.
1627 static sctp_cookie_param_t *sctp_pack_cookie(const struct sctp_endpoint *ep,
1628 const struct sctp_association *asoc,
1629 const struct sctp_chunk *init_chunk,
1631 const __u8 *raw_addrs, int addrs_len)
1633 sctp_cookie_param_t *retval;
1634 struct sctp_signed_cookie *cookie;
1635 int headersize, bodysize;
1637 /* Header size is static data prior to the actual cookie, including
1640 headersize = sizeof(sctp_paramhdr_t) +
1641 (sizeof(struct sctp_signed_cookie) -
1642 sizeof(struct sctp_cookie));
1643 bodysize = sizeof(struct sctp_cookie)
1644 + ntohs(init_chunk->chunk_hdr->length) + addrs_len;
1646 /* Pad out the cookie to a multiple to make the signature
1647 * functions simpler to write.
1649 if (bodysize % SCTP_COOKIE_MULTIPLE)
1650 bodysize += SCTP_COOKIE_MULTIPLE
1651 - (bodysize % SCTP_COOKIE_MULTIPLE);
1652 *cookie_len = headersize + bodysize;
1654 /* Clear this memory since we are sending this data structure
1655 * out on the network.
1657 retval = kzalloc(*cookie_len, GFP_ATOMIC);
1661 cookie = (struct sctp_signed_cookie *) retval->body;
1663 /* Set up the parameter header. */
1664 retval->p.type = SCTP_PARAM_STATE_COOKIE;
1665 retval->p.length = htons(*cookie_len);
1667 /* Copy the cookie part of the association itself. */
1668 cookie->c = asoc->c;
1669 /* Save the raw address list length in the cookie. */
1670 cookie->c.raw_addr_list_len = addrs_len;
1672 /* Remember PR-SCTP capability. */
1673 cookie->c.prsctp_capable = asoc->peer.prsctp_capable;
1675 /* Save adaptation indication in the cookie. */
1676 cookie->c.adaptation_ind = asoc->peer.adaptation_ind;
1678 /* Set an expiration time for the cookie. */
1679 cookie->c.expiration = ktime_add(asoc->cookie_life,
1682 /* Copy the peer's init packet. */
1683 memcpy(&cookie->c.peer_init[0], init_chunk->chunk_hdr,
1684 ntohs(init_chunk->chunk_hdr->length));
1686 /* Copy the raw local address list of the association. */
1687 memcpy((__u8 *)&cookie->c.peer_init[0] +
1688 ntohs(init_chunk->chunk_hdr->length), raw_addrs, addrs_len);
1690 if (sctp_sk(ep->base.sk)->hmac) {
1691 SHASH_DESC_ON_STACK(desc, sctp_sk(ep->base.sk)->hmac);
1694 /* Sign the message. */
1695 desc->tfm = sctp_sk(ep->base.sk)->hmac;
1698 err = crypto_shash_setkey(desc->tfm, ep->secret_key,
1699 sizeof(ep->secret_key)) ?:
1700 crypto_shash_digest(desc, (u8 *)&cookie->c, bodysize,
1702 shash_desc_zero(desc);
1716 /* Unpack the cookie from COOKIE ECHO chunk, recreating the association. */
1717 struct sctp_association *sctp_unpack_cookie(
1718 const struct sctp_endpoint *ep,
1719 const struct sctp_association *asoc,
1720 struct sctp_chunk *chunk, gfp_t gfp,
1721 int *error, struct sctp_chunk **errp)
1723 struct sctp_association *retval = NULL;
1724 struct sctp_signed_cookie *cookie;
1725 struct sctp_cookie *bear_cookie;
1726 int headersize, bodysize, fixed_size;
1727 __u8 *digest = ep->digest;
1730 struct sk_buff *skb = chunk->skb;
1733 /* Header size is static data prior to the actual cookie, including
1736 headersize = sizeof(sctp_chunkhdr_t) +
1737 (sizeof(struct sctp_signed_cookie) -
1738 sizeof(struct sctp_cookie));
1739 bodysize = ntohs(chunk->chunk_hdr->length) - headersize;
1740 fixed_size = headersize + sizeof(struct sctp_cookie);
1742 /* Verify that the chunk looks like it even has a cookie.
1743 * There must be enough room for our cookie and our peer's
1746 len = ntohs(chunk->chunk_hdr->length);
1747 if (len < fixed_size + sizeof(struct sctp_chunkhdr))
1750 /* Verify that the cookie has been padded out. */
1751 if (bodysize % SCTP_COOKIE_MULTIPLE)
1754 /* Process the cookie. */
1755 cookie = chunk->subh.cookie_hdr;
1756 bear_cookie = &cookie->c;
1758 if (!sctp_sk(ep->base.sk)->hmac)
1761 /* Check the signature. */
1763 SHASH_DESC_ON_STACK(desc, sctp_sk(ep->base.sk)->hmac);
1766 desc->tfm = sctp_sk(ep->base.sk)->hmac;
1769 err = crypto_shash_setkey(desc->tfm, ep->secret_key,
1770 sizeof(ep->secret_key)) ?:
1771 crypto_shash_digest(desc, (u8 *)bear_cookie, bodysize,
1773 shash_desc_zero(desc);
1776 *error = -SCTP_IERROR_NOMEM;
1781 if (memcmp(digest, cookie->signature, SCTP_SIGNATURE_SIZE)) {
1782 *error = -SCTP_IERROR_BAD_SIG;
1787 /* IG Section 2.35.2:
1788 * 3) Compare the port numbers and the verification tag contained
1789 * within the COOKIE ECHO chunk to the actual port numbers and the
1790 * verification tag within the SCTP common header of the received
1791 * packet. If these values do not match the packet MUST be silently
1794 if (ntohl(chunk->sctp_hdr->vtag) != bear_cookie->my_vtag) {
1795 *error = -SCTP_IERROR_BAD_TAG;
1799 if (chunk->sctp_hdr->source != bear_cookie->peer_addr.v4.sin_port ||
1800 ntohs(chunk->sctp_hdr->dest) != bear_cookie->my_port) {
1801 *error = -SCTP_IERROR_BAD_PORTS;
1805 /* Check to see if the cookie is stale. If there is already
1806 * an association, there is no need to check cookie's expiration
1807 * for init collision case of lost COOKIE ACK.
1808 * If skb has been timestamped, then use the stamp, otherwise
1809 * use current time. This introduces a small possibility that
1810 * that a cookie may be considered expired, but his would only slow
1811 * down the new association establishment instead of every packet.
1813 if (sock_flag(ep->base.sk, SOCK_TIMESTAMP))
1814 kt = skb_get_ktime(skb);
1816 kt = ktime_get_real();
1818 if (!asoc && ktime_before(bear_cookie->expiration, kt)) {
1820 * Section 3.3.10.3 Stale Cookie Error (3)
1824 * Stale Cookie Error: Indicates the receipt of a valid State
1825 * Cookie that has expired.
1827 len = ntohs(chunk->chunk_hdr->length);
1828 *errp = sctp_make_op_error_space(asoc, chunk, len);
1830 suseconds_t usecs = ktime_to_us(ktime_sub(kt, bear_cookie->expiration));
1831 __be32 n = htonl(usecs);
1833 sctp_init_cause(*errp, SCTP_ERROR_STALE_COOKIE,
1835 sctp_addto_chunk(*errp, sizeof(n), &n);
1836 *error = -SCTP_IERROR_STALE_COOKIE;
1838 *error = -SCTP_IERROR_NOMEM;
1843 /* Make a new base association. */
1844 scope = sctp_scope(sctp_source(chunk));
1845 retval = sctp_association_new(ep, ep->base.sk, scope, gfp);
1847 *error = -SCTP_IERROR_NOMEM;
1851 /* Set up our peer's port number. */
1852 retval->peer.port = ntohs(chunk->sctp_hdr->source);
1854 /* Populate the association from the cookie. */
1855 memcpy(&retval->c, bear_cookie, sizeof(*bear_cookie));
1857 if (sctp_assoc_set_bind_addr_from_cookie(retval, bear_cookie,
1859 *error = -SCTP_IERROR_NOMEM;
1863 /* Also, add the destination address. */
1864 if (list_empty(&retval->base.bind_addr.address_list)) {
1865 sctp_add_bind_addr(&retval->base.bind_addr, &chunk->dest,
1866 sizeof(chunk->dest), SCTP_ADDR_SRC,
1870 retval->next_tsn = retval->c.initial_tsn;
1871 retval->ctsn_ack_point = retval->next_tsn - 1;
1872 retval->addip_serial = retval->c.initial_tsn;
1873 retval->adv_peer_ack_point = retval->ctsn_ack_point;
1874 retval->peer.prsctp_capable = retval->c.prsctp_capable;
1875 retval->peer.adaptation_ind = retval->c.adaptation_ind;
1877 /* The INIT stuff will be done by the side effects. */
1882 sctp_association_free(retval);
1887 /* Yikes! The packet is either corrupt or deliberately
1890 *error = -SCTP_IERROR_MALFORMED;
1894 /********************************************************************
1895 * 3rd Level Abstractions
1896 ********************************************************************/
1898 struct __sctp_missing {
1904 * Report a missing mandatory parameter.
1906 static int sctp_process_missing_param(const struct sctp_association *asoc,
1907 sctp_param_t paramtype,
1908 struct sctp_chunk *chunk,
1909 struct sctp_chunk **errp)
1911 struct __sctp_missing report;
1914 len = WORD_ROUND(sizeof(report));
1916 /* Make an ERROR chunk, preparing enough room for
1917 * returning multiple unknown parameters.
1920 *errp = sctp_make_op_error_space(asoc, chunk, len);
1923 report.num_missing = htonl(1);
1924 report.type = paramtype;
1925 sctp_init_cause(*errp, SCTP_ERROR_MISS_PARAM,
1927 sctp_addto_chunk(*errp, sizeof(report), &report);
1930 /* Stop processing this chunk. */
1934 /* Report an Invalid Mandatory Parameter. */
1935 static int sctp_process_inv_mandatory(const struct sctp_association *asoc,
1936 struct sctp_chunk *chunk,
1937 struct sctp_chunk **errp)
1939 /* Invalid Mandatory Parameter Error has no payload. */
1942 *errp = sctp_make_op_error_space(asoc, chunk, 0);
1945 sctp_init_cause(*errp, SCTP_ERROR_INV_PARAM, 0);
1947 /* Stop processing this chunk. */
1951 static int sctp_process_inv_paramlength(const struct sctp_association *asoc,
1952 struct sctp_paramhdr *param,
1953 const struct sctp_chunk *chunk,
1954 struct sctp_chunk **errp)
1956 /* This is a fatal error. Any accumulated non-fatal errors are
1960 sctp_chunk_free(*errp);
1962 /* Create an error chunk and fill it in with our payload. */
1963 *errp = sctp_make_violation_paramlen(asoc, chunk, param);
1969 /* Do not attempt to handle the HOST_NAME parm. However, do
1970 * send back an indicator to the peer.
1972 static int sctp_process_hn_param(const struct sctp_association *asoc,
1973 union sctp_params param,
1974 struct sctp_chunk *chunk,
1975 struct sctp_chunk **errp)
1977 __u16 len = ntohs(param.p->length);
1979 /* Processing of the HOST_NAME parameter will generate an
1980 * ABORT. If we've accumulated any non-fatal errors, they
1981 * would be unrecognized parameters and we should not include
1982 * them in the ABORT.
1985 sctp_chunk_free(*errp);
1987 *errp = sctp_make_op_error_space(asoc, chunk, len);
1990 sctp_init_cause(*errp, SCTP_ERROR_DNS_FAILED, len);
1991 sctp_addto_chunk(*errp, len, param.v);
1994 /* Stop processing this chunk. */
1998 static int sctp_verify_ext_param(struct net *net, union sctp_params param)
2000 __u16 num_ext = ntohs(param.p->length) - sizeof(sctp_paramhdr_t);
2002 int have_asconf = 0;
2005 for (i = 0; i < num_ext; i++) {
2006 switch (param.ext->chunks[i]) {
2010 case SCTP_CID_ASCONF:
2011 case SCTP_CID_ASCONF_ACK:
2017 /* ADD-IP Security: The draft requires us to ABORT or ignore the
2018 * INIT/INIT-ACK if ADD-IP is listed, but AUTH is not. Do this
2019 * only if ADD-IP is turned on and we are not backward-compatible
2022 if (net->sctp.addip_noauth)
2025 if (net->sctp.addip_enable && !have_auth && have_asconf)
2031 static void sctp_process_ext_param(struct sctp_association *asoc,
2032 union sctp_params param)
2034 struct net *net = sock_net(asoc->base.sk);
2035 __u16 num_ext = ntohs(param.p->length) - sizeof(sctp_paramhdr_t);
2038 for (i = 0; i < num_ext; i++) {
2039 switch (param.ext->chunks[i]) {
2040 case SCTP_CID_FWD_TSN:
2041 if (asoc->prsctp_enable && !asoc->peer.prsctp_capable)
2042 asoc->peer.prsctp_capable = 1;
2045 /* if the peer reports AUTH, assume that he
2048 if (asoc->ep->auth_enable)
2049 asoc->peer.auth_capable = 1;
2051 case SCTP_CID_ASCONF:
2052 case SCTP_CID_ASCONF_ACK:
2053 if (net->sctp.addip_enable)
2054 asoc->peer.asconf_capable = 1;
2062 /* RFC 3.2.1 & the Implementers Guide 2.2.
2064 * The Parameter Types are encoded such that the
2065 * highest-order two bits specify the action that must be
2066 * taken if the processing endpoint does not recognize the
2069 * 00 - Stop processing this parameter; do not process any further
2070 * parameters within this chunk
2072 * 01 - Stop processing this parameter, do not process any further
2073 * parameters within this chunk, and report the unrecognized
2074 * parameter in an 'Unrecognized Parameter' ERROR chunk.
2076 * 10 - Skip this parameter and continue processing.
2078 * 11 - Skip this parameter and continue processing but
2079 * report the unrecognized parameter in an
2080 * 'Unrecognized Parameter' ERROR chunk.
2083 * SCTP_IERROR_NO_ERROR - continue with the chunk
2084 * SCTP_IERROR_ERROR - stop and report an error.
2085 * SCTP_IERROR_NOMEME - out of memory.
2087 static sctp_ierror_t sctp_process_unk_param(const struct sctp_association *asoc,
2088 union sctp_params param,
2089 struct sctp_chunk *chunk,
2090 struct sctp_chunk **errp)
2092 int retval = SCTP_IERROR_NO_ERROR;
2094 switch (param.p->type & SCTP_PARAM_ACTION_MASK) {
2095 case SCTP_PARAM_ACTION_DISCARD:
2096 retval = SCTP_IERROR_ERROR;
2098 case SCTP_PARAM_ACTION_SKIP:
2100 case SCTP_PARAM_ACTION_DISCARD_ERR:
2101 retval = SCTP_IERROR_ERROR;
2103 case SCTP_PARAM_ACTION_SKIP_ERR:
2104 /* Make an ERROR chunk, preparing enough room for
2105 * returning multiple unknown parameters.
2108 *errp = sctp_make_op_error_fixed(asoc, chunk);
2111 if (!sctp_init_cause_fixed(*errp, SCTP_ERROR_UNKNOWN_PARAM,
2112 WORD_ROUND(ntohs(param.p->length))))
2113 sctp_addto_chunk_fixed(*errp,
2114 WORD_ROUND(ntohs(param.p->length)),
2117 /* If there is no memory for generating the ERROR
2118 * report as specified, an ABORT will be triggered
2119 * to the peer and the association won't be
2122 retval = SCTP_IERROR_NOMEM;
2132 /* Verify variable length parameters
2134 * SCTP_IERROR_ABORT - trigger an ABORT
2135 * SCTP_IERROR_NOMEM - out of memory (abort)
2136 * SCTP_IERROR_ERROR - stop processing, trigger an ERROR
2137 * SCTP_IERROR_NO_ERROR - continue with the chunk
2139 static sctp_ierror_t sctp_verify_param(struct net *net,
2140 const struct sctp_endpoint *ep,
2141 const struct sctp_association *asoc,
2142 union sctp_params param,
2144 struct sctp_chunk *chunk,
2145 struct sctp_chunk **err_chunk)
2147 struct sctp_hmac_algo_param *hmacs;
2148 int retval = SCTP_IERROR_NO_ERROR;
2149 __u16 n_elt, id = 0;
2152 /* FIXME - This routine is not looking at each parameter per the
2153 * chunk type, i.e., unrecognized parameters should be further
2154 * identified based on the chunk id.
2157 switch (param.p->type) {
2158 case SCTP_PARAM_IPV4_ADDRESS:
2159 case SCTP_PARAM_IPV6_ADDRESS:
2160 case SCTP_PARAM_COOKIE_PRESERVATIVE:
2161 case SCTP_PARAM_SUPPORTED_ADDRESS_TYPES:
2162 case SCTP_PARAM_STATE_COOKIE:
2163 case SCTP_PARAM_HEARTBEAT_INFO:
2164 case SCTP_PARAM_UNRECOGNIZED_PARAMETERS:
2165 case SCTP_PARAM_ECN_CAPABLE:
2166 case SCTP_PARAM_ADAPTATION_LAYER_IND:
2169 case SCTP_PARAM_SUPPORTED_EXT:
2170 if (!sctp_verify_ext_param(net, param))
2171 return SCTP_IERROR_ABORT;
2174 case SCTP_PARAM_SET_PRIMARY:
2175 if (net->sctp.addip_enable)
2179 case SCTP_PARAM_HOST_NAME_ADDRESS:
2180 /* Tell the peer, we won't support this param. */
2181 sctp_process_hn_param(asoc, param, chunk, err_chunk);
2182 retval = SCTP_IERROR_ABORT;
2185 case SCTP_PARAM_FWD_TSN_SUPPORT:
2186 if (ep->prsctp_enable)
2190 case SCTP_PARAM_RANDOM:
2191 if (!ep->auth_enable)
2194 /* SCTP-AUTH: Secion 6.1
2195 * If the random number is not 32 byte long the association
2196 * MUST be aborted. The ABORT chunk SHOULD contain the error
2197 * cause 'Protocol Violation'.
2199 if (SCTP_AUTH_RANDOM_LENGTH !=
2200 ntohs(param.p->length) - sizeof(sctp_paramhdr_t)) {
2201 sctp_process_inv_paramlength(asoc, param.p,
2203 retval = SCTP_IERROR_ABORT;
2207 case SCTP_PARAM_CHUNKS:
2208 if (!ep->auth_enable)
2211 /* SCTP-AUTH: Section 3.2
2212 * The CHUNKS parameter MUST be included once in the INIT or
2213 * INIT-ACK chunk if the sender wants to receive authenticated
2214 * chunks. Its maximum length is 260 bytes.
2216 if (260 < ntohs(param.p->length)) {
2217 sctp_process_inv_paramlength(asoc, param.p,
2219 retval = SCTP_IERROR_ABORT;
2223 case SCTP_PARAM_HMAC_ALGO:
2224 if (!ep->auth_enable)
2227 hmacs = (struct sctp_hmac_algo_param *)param.p;
2228 n_elt = (ntohs(param.p->length) - sizeof(sctp_paramhdr_t)) >> 1;
2230 /* SCTP-AUTH: Section 6.1
2231 * The HMAC algorithm based on SHA-1 MUST be supported and
2232 * included in the HMAC-ALGO parameter.
2234 for (i = 0; i < n_elt; i++) {
2235 id = ntohs(hmacs->hmac_ids[i]);
2237 if (id == SCTP_AUTH_HMAC_ID_SHA1)
2241 if (id != SCTP_AUTH_HMAC_ID_SHA1) {
2242 sctp_process_inv_paramlength(asoc, param.p, chunk,
2244 retval = SCTP_IERROR_ABORT;
2249 pr_debug("%s: unrecognized param:%d for chunk:%d\n",
2250 __func__, ntohs(param.p->type), cid);
2252 retval = sctp_process_unk_param(asoc, param, chunk, err_chunk);
2258 /* Verify the INIT packet before we process it. */
2259 int sctp_verify_init(struct net *net, const struct sctp_endpoint *ep,
2260 const struct sctp_association *asoc, sctp_cid_t cid,
2261 sctp_init_chunk_t *peer_init, struct sctp_chunk *chunk,
2262 struct sctp_chunk **errp)
2264 union sctp_params param;
2265 bool has_cookie = false;
2268 /* Check for missing mandatory parameters. Note: Initial TSN is
2269 * also mandatory, but is not checked here since the valid range
2270 * is 0..2**32-1. RFC4960, section 3.3.3.
2272 if (peer_init->init_hdr.num_outbound_streams == 0 ||
2273 peer_init->init_hdr.num_inbound_streams == 0 ||
2274 peer_init->init_hdr.init_tag == 0 ||
2275 ntohl(peer_init->init_hdr.a_rwnd) < SCTP_DEFAULT_MINWINDOW)
2276 return sctp_process_inv_mandatory(asoc, chunk, errp);
2278 sctp_walk_params(param, peer_init, init_hdr.params) {
2279 if (param.p->type == SCTP_PARAM_STATE_COOKIE)
2283 /* There is a possibility that a parameter length was bad and
2284 * in that case we would have stoped walking the parameters.
2285 * The current param.p would point at the bad one.
2286 * Current consensus on the mailing list is to generate a PROTOCOL
2287 * VIOLATION error. We build the ERROR chunk here and let the normal
2288 * error handling code build and send the packet.
2290 if (param.v != (void *)chunk->chunk_end)
2291 return sctp_process_inv_paramlength(asoc, param.p, chunk, errp);
2293 /* The only missing mandatory param possible today is
2294 * the state cookie for an INIT-ACK chunk.
2296 if ((SCTP_CID_INIT_ACK == cid) && !has_cookie)
2297 return sctp_process_missing_param(asoc, SCTP_PARAM_STATE_COOKIE,
2300 /* Verify all the variable length parameters */
2301 sctp_walk_params(param, peer_init, init_hdr.params) {
2302 result = sctp_verify_param(net, ep, asoc, param, cid,
2305 case SCTP_IERROR_ABORT:
2306 case SCTP_IERROR_NOMEM:
2308 case SCTP_IERROR_ERROR:
2310 case SCTP_IERROR_NO_ERROR:
2315 } /* for (loop through all parameters) */
2320 /* Unpack the parameters in an INIT packet into an association.
2321 * Returns 0 on failure, else success.
2322 * FIXME: This is an association method.
2324 int sctp_process_init(struct sctp_association *asoc, struct sctp_chunk *chunk,
2325 const union sctp_addr *peer_addr,
2326 sctp_init_chunk_t *peer_init, gfp_t gfp)
2328 struct net *net = sock_net(asoc->base.sk);
2329 union sctp_params param;
2330 struct sctp_transport *transport;
2331 struct list_head *pos, *temp;
2333 union sctp_addr addr;
2337 /* We must include the address that the INIT packet came from.
2338 * This is the only address that matters for an INIT packet.
2339 * When processing a COOKIE ECHO, we retrieve the from address
2340 * of the INIT from the cookie.
2343 /* This implementation defaults to making the first transport
2344 * added as the primary transport. The source address seems to
2345 * be a a better choice than any of the embedded addresses.
2347 if (!sctp_assoc_add_peer(asoc, peer_addr, gfp, SCTP_ACTIVE))
2350 if (sctp_cmp_addr_exact(sctp_source(chunk), peer_addr))
2353 /* Process the initialization parameters. */
2354 sctp_walk_params(param, peer_init, init_hdr.params) {
2355 if (!src_match && (param.p->type == SCTP_PARAM_IPV4_ADDRESS ||
2356 param.p->type == SCTP_PARAM_IPV6_ADDRESS)) {
2357 af = sctp_get_af_specific(param_type2af(param.p->type));
2358 af->from_addr_param(&addr, param.addr,
2359 chunk->sctp_hdr->source, 0);
2360 if (sctp_cmp_addr_exact(sctp_source(chunk), &addr))
2364 if (!sctp_process_param(asoc, param, peer_addr, gfp))
2368 /* source address of chunk may not match any valid address */
2372 /* AUTH: After processing the parameters, make sure that we
2373 * have all the required info to potentially do authentications.
2375 if (asoc->peer.auth_capable && (!asoc->peer.peer_random ||
2376 !asoc->peer.peer_hmacs))
2377 asoc->peer.auth_capable = 0;
2379 /* In a non-backward compatible mode, if the peer claims
2380 * support for ADD-IP but not AUTH, the ADD-IP spec states
2381 * that we MUST ABORT the association. Section 6. The section
2382 * also give us an option to silently ignore the packet, which
2383 * is what we'll do here.
2385 if (!net->sctp.addip_noauth &&
2386 (asoc->peer.asconf_capable && !asoc->peer.auth_capable)) {
2387 asoc->peer.addip_disabled_mask |= (SCTP_PARAM_ADD_IP |
2389 SCTP_PARAM_SET_PRIMARY);
2390 asoc->peer.asconf_capable = 0;
2394 /* Walk list of transports, removing transports in the UNKNOWN state. */
2395 list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
2396 transport = list_entry(pos, struct sctp_transport, transports);
2397 if (transport->state == SCTP_UNKNOWN) {
2398 sctp_assoc_rm_peer(asoc, transport);
2402 /* The fixed INIT headers are always in network byte
2405 asoc->peer.i.init_tag =
2406 ntohl(peer_init->init_hdr.init_tag);
2407 asoc->peer.i.a_rwnd =
2408 ntohl(peer_init->init_hdr.a_rwnd);
2409 asoc->peer.i.num_outbound_streams =
2410 ntohs(peer_init->init_hdr.num_outbound_streams);
2411 asoc->peer.i.num_inbound_streams =
2412 ntohs(peer_init->init_hdr.num_inbound_streams);
2413 asoc->peer.i.initial_tsn =
2414 ntohl(peer_init->init_hdr.initial_tsn);
2416 /* Apply the upper bounds for output streams based on peer's
2417 * number of inbound streams.
2419 if (asoc->c.sinit_num_ostreams >
2420 ntohs(peer_init->init_hdr.num_inbound_streams)) {
2421 asoc->c.sinit_num_ostreams =
2422 ntohs(peer_init->init_hdr.num_inbound_streams);
2425 if (asoc->c.sinit_max_instreams >
2426 ntohs(peer_init->init_hdr.num_outbound_streams)) {
2427 asoc->c.sinit_max_instreams =
2428 ntohs(peer_init->init_hdr.num_outbound_streams);
2431 /* Copy Initiation tag from INIT to VT_peer in cookie. */
2432 asoc->c.peer_vtag = asoc->peer.i.init_tag;
2434 /* Peer Rwnd : Current calculated value of the peer's rwnd. */
2435 asoc->peer.rwnd = asoc->peer.i.a_rwnd;
2437 /* Copy cookie in case we need to resend COOKIE-ECHO. */
2438 cookie = asoc->peer.cookie;
2440 asoc->peer.cookie = kmemdup(cookie, asoc->peer.cookie_len, gfp);
2441 if (!asoc->peer.cookie)
2445 /* RFC 2960 7.2.1 The initial value of ssthresh MAY be arbitrarily
2446 * high (for example, implementations MAY use the size of the receiver
2447 * advertised window).
2449 list_for_each_entry(transport, &asoc->peer.transport_addr_list,
2451 transport->ssthresh = asoc->peer.i.a_rwnd;
2454 /* Set up the TSN tracking pieces. */
2455 if (!sctp_tsnmap_init(&asoc->peer.tsn_map, SCTP_TSN_MAP_INITIAL,
2456 asoc->peer.i.initial_tsn, gfp))
2459 /* RFC 2960 6.5 Stream Identifier and Stream Sequence Number
2461 * The stream sequence number in all the streams shall start
2462 * from 0 when the association is established. Also, when the
2463 * stream sequence number reaches the value 65535 the next
2464 * stream sequence number shall be set to 0.
2467 /* Allocate storage for the negotiated streams if it is not a temporary
2473 asoc->ssnmap = sctp_ssnmap_new(asoc->c.sinit_max_instreams,
2474 asoc->c.sinit_num_ostreams, gfp);
2478 error = sctp_assoc_set_id(asoc, gfp);
2483 /* ADDIP Section 4.1 ASCONF Chunk Procedures
2485 * When an endpoint has an ASCONF signaled change to be sent to the
2486 * remote endpoint it should do the following:
2488 * A2) A serial number should be assigned to the Chunk. The serial
2489 * number should be a monotonically increasing number. All serial
2490 * numbers are defined to be initialized at the start of the
2491 * association to the same value as the Initial TSN.
2493 asoc->peer.addip_serial = asoc->peer.i.initial_tsn - 1;
2497 /* Release the transport structures. */
2498 list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
2499 transport = list_entry(pos, struct sctp_transport, transports);
2500 if (transport->state != SCTP_ACTIVE)
2501 sctp_assoc_rm_peer(asoc, transport);
2509 /* Update asoc with the option described in param.
2511 * RFC2960 3.3.2.1 Optional/Variable Length Parameters in INIT
2513 * asoc is the association to update.
2514 * param is the variable length parameter to use for update.
2515 * cid tells us if this is an INIT, INIT ACK or COOKIE ECHO.
2516 * If the current packet is an INIT we want to minimize the amount of
2517 * work we do. In particular, we should not build transport
2518 * structures for the addresses.
2520 static int sctp_process_param(struct sctp_association *asoc,
2521 union sctp_params param,
2522 const union sctp_addr *peer_addr,
2525 struct net *net = sock_net(asoc->base.sk);
2526 union sctp_addr addr;
2533 union sctp_addr_param *addr_param;
2534 struct sctp_transport *t;
2535 struct sctp_endpoint *ep = asoc->ep;
2537 /* We maintain all INIT parameters in network byte order all the
2538 * time. This allows us to not worry about whether the parameters
2539 * came from a fresh INIT, and INIT ACK, or were stored in a cookie.
2541 switch (param.p->type) {
2542 case SCTP_PARAM_IPV6_ADDRESS:
2543 if (PF_INET6 != asoc->base.sk->sk_family)
2547 case SCTP_PARAM_IPV4_ADDRESS:
2548 /* v4 addresses are not allowed on v6-only socket */
2549 if (ipv6_only_sock(asoc->base.sk))
2552 af = sctp_get_af_specific(param_type2af(param.p->type));
2553 af->from_addr_param(&addr, param.addr, htons(asoc->peer.port), 0);
2554 scope = sctp_scope(peer_addr);
2555 if (sctp_in_scope(net, &addr, scope))
2556 if (!sctp_assoc_add_peer(asoc, &addr, gfp, SCTP_UNCONFIRMED))
2560 case SCTP_PARAM_COOKIE_PRESERVATIVE:
2561 if (!net->sctp.cookie_preserve_enable)
2564 stale = ntohl(param.life->lifespan_increment);
2566 /* Suggested Cookie Life span increment's unit is msec,
2569 asoc->cookie_life = ktime_add_ms(asoc->cookie_life, stale);
2572 case SCTP_PARAM_HOST_NAME_ADDRESS:
2573 pr_debug("%s: unimplemented SCTP_HOST_NAME_ADDRESS\n", __func__);
2576 case SCTP_PARAM_SUPPORTED_ADDRESS_TYPES:
2577 /* Turn off the default values first so we'll know which
2578 * ones are really set by the peer.
2580 asoc->peer.ipv4_address = 0;
2581 asoc->peer.ipv6_address = 0;
2583 /* Assume that peer supports the address family
2584 * by which it sends a packet.
2586 if (peer_addr->sa.sa_family == AF_INET6)
2587 asoc->peer.ipv6_address = 1;
2588 else if (peer_addr->sa.sa_family == AF_INET)
2589 asoc->peer.ipv4_address = 1;
2591 /* Cycle through address types; avoid divide by 0. */
2592 sat = ntohs(param.p->length) - sizeof(sctp_paramhdr_t);
2594 sat /= sizeof(__u16);
2596 for (i = 0; i < sat; ++i) {
2597 switch (param.sat->types[i]) {
2598 case SCTP_PARAM_IPV4_ADDRESS:
2599 asoc->peer.ipv4_address = 1;
2602 case SCTP_PARAM_IPV6_ADDRESS:
2603 if (PF_INET6 == asoc->base.sk->sk_family)
2604 asoc->peer.ipv6_address = 1;
2607 case SCTP_PARAM_HOST_NAME_ADDRESS:
2608 asoc->peer.hostname_address = 1;
2611 default: /* Just ignore anything else. */
2617 case SCTP_PARAM_STATE_COOKIE:
2618 asoc->peer.cookie_len =
2619 ntohs(param.p->length) - sizeof(sctp_paramhdr_t);
2620 asoc->peer.cookie = param.cookie->body;
2623 case SCTP_PARAM_HEARTBEAT_INFO:
2624 /* Would be odd to receive, but it causes no problems. */
2627 case SCTP_PARAM_UNRECOGNIZED_PARAMETERS:
2628 /* Rejected during verify stage. */
2631 case SCTP_PARAM_ECN_CAPABLE:
2632 asoc->peer.ecn_capable = 1;
2635 case SCTP_PARAM_ADAPTATION_LAYER_IND:
2636 asoc->peer.adaptation_ind = ntohl(param.aind->adaptation_ind);
2639 case SCTP_PARAM_SET_PRIMARY:
2640 if (!net->sctp.addip_enable)
2643 addr_param = param.v + sizeof(sctp_addip_param_t);
2645 af = sctp_get_af_specific(param_type2af(addr_param->p.type));
2649 af->from_addr_param(&addr, addr_param,
2650 htons(asoc->peer.port), 0);
2652 /* if the address is invalid, we can't process it.
2653 * XXX: see spec for what to do.
2655 if (!af->addr_valid(&addr, NULL, NULL))
2658 t = sctp_assoc_lookup_paddr(asoc, &addr);
2662 sctp_assoc_set_primary(asoc, t);
2665 case SCTP_PARAM_SUPPORTED_EXT:
2666 sctp_process_ext_param(asoc, param);
2669 case SCTP_PARAM_FWD_TSN_SUPPORT:
2670 if (asoc->prsctp_enable) {
2671 asoc->peer.prsctp_capable = 1;
2677 case SCTP_PARAM_RANDOM:
2678 if (!ep->auth_enable)
2681 /* Save peer's random parameter */
2682 asoc->peer.peer_random = kmemdup(param.p,
2683 ntohs(param.p->length), gfp);
2684 if (!asoc->peer.peer_random) {
2690 case SCTP_PARAM_HMAC_ALGO:
2691 if (!ep->auth_enable)
2694 /* Save peer's HMAC list */
2695 asoc->peer.peer_hmacs = kmemdup(param.p,
2696 ntohs(param.p->length), gfp);
2697 if (!asoc->peer.peer_hmacs) {
2702 /* Set the default HMAC the peer requested*/
2703 sctp_auth_asoc_set_default_hmac(asoc, param.hmac_algo);
2706 case SCTP_PARAM_CHUNKS:
2707 if (!ep->auth_enable)
2710 asoc->peer.peer_chunks = kmemdup(param.p,
2711 ntohs(param.p->length), gfp);
2712 if (!asoc->peer.peer_chunks)
2717 /* Any unrecognized parameters should have been caught
2718 * and handled by sctp_verify_param() which should be
2719 * called prior to this routine. Simply log the error
2722 pr_debug("%s: ignoring param:%d for association:%p.\n",
2723 __func__, ntohs(param.p->type), asoc);
2730 /* Select a new verification tag. */
2731 __u32 sctp_generate_tag(const struct sctp_endpoint *ep)
2733 /* I believe that this random number generator complies with RFC1750.
2734 * A tag of 0 is reserved for special cases (e.g. INIT).
2739 get_random_bytes(&x, sizeof(__u32));
2745 /* Select an initial TSN to send during startup. */
2746 __u32 sctp_generate_tsn(const struct sctp_endpoint *ep)
2750 get_random_bytes(&retval, sizeof(__u32));
2755 * ADDIP 3.1.1 Address Configuration Change Chunk (ASCONF)
2757 * 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
2758 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2759 * | Type = 0xC1 | Chunk Flags | Chunk Length |
2760 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2762 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2763 * | Address Parameter |
2764 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2765 * | ASCONF Parameter #1 |
2766 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2770 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2771 * | ASCONF Parameter #N |
2772 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2774 * Address Parameter and other parameter will not be wrapped in this function
2776 static struct sctp_chunk *sctp_make_asconf(struct sctp_association *asoc,
2777 union sctp_addr *addr,
2780 sctp_addiphdr_t asconf;
2781 struct sctp_chunk *retval;
2782 int length = sizeof(asconf) + vparam_len;
2783 union sctp_addr_param addrparam;
2785 struct sctp_af *af = sctp_get_af_specific(addr->v4.sin_family);
2787 addrlen = af->to_addr_param(addr, &addrparam);
2792 /* Create the chunk. */
2793 retval = sctp_make_control(asoc, SCTP_CID_ASCONF, 0, length,
2798 asconf.serial = htonl(asoc->addip_serial++);
2800 retval->subh.addip_hdr =
2801 sctp_addto_chunk(retval, sizeof(asconf), &asconf);
2802 retval->param_hdr.v =
2803 sctp_addto_chunk(retval, addrlen, &addrparam);
2809 * 3.2.1 Add IP Address
2811 * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
2812 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2813 * | Type = 0xC001 | Length = Variable |
2814 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2815 * | ASCONF-Request Correlation ID |
2816 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2817 * | Address Parameter |
2818 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2820 * 3.2.2 Delete IP Address
2822 * 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
2823 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2824 * | Type = 0xC002 | Length = Variable |
2825 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2826 * | ASCONF-Request Correlation ID |
2827 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2828 * | Address Parameter |
2829 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2832 struct sctp_chunk *sctp_make_asconf_update_ip(struct sctp_association *asoc,
2833 union sctp_addr *laddr,
2834 struct sockaddr *addrs,
2838 sctp_addip_param_t param;
2839 struct sctp_chunk *retval;
2840 union sctp_addr_param addr_param;
2841 union sctp_addr *addr;
2844 int paramlen = sizeof(param);
2845 int addr_param_len = 0;
2850 /* Get total length of all the address parameters. */
2852 for (i = 0; i < addrcnt; i++) {
2854 af = sctp_get_af_specific(addr->v4.sin_family);
2855 addr_param_len = af->to_addr_param(addr, &addr_param);
2857 totallen += paramlen;
2858 totallen += addr_param_len;
2860 addr_buf += af->sockaddr_len;
2861 if (asoc->asconf_addr_del_pending && !del_pickup) {
2862 /* reuse the parameter length from the same scope one */
2863 totallen += paramlen;
2864 totallen += addr_param_len;
2867 pr_debug("%s: picked same-scope del_pending addr, "
2868 "totallen for all addresses is %d\n",
2869 __func__, totallen);
2873 /* Create an asconf chunk with the required length. */
2874 retval = sctp_make_asconf(asoc, laddr, totallen);
2878 /* Add the address parameters to the asconf chunk. */
2880 for (i = 0; i < addrcnt; i++) {
2882 af = sctp_get_af_specific(addr->v4.sin_family);
2883 addr_param_len = af->to_addr_param(addr, &addr_param);
2884 param.param_hdr.type = flags;
2885 param.param_hdr.length = htons(paramlen + addr_param_len);
2888 sctp_addto_chunk(retval, paramlen, ¶m);
2889 sctp_addto_chunk(retval, addr_param_len, &addr_param);
2891 addr_buf += af->sockaddr_len;
2893 if (flags == SCTP_PARAM_ADD_IP && del_pickup) {
2894 addr = asoc->asconf_addr_del_pending;
2895 af = sctp_get_af_specific(addr->v4.sin_family);
2896 addr_param_len = af->to_addr_param(addr, &addr_param);
2897 param.param_hdr.type = SCTP_PARAM_DEL_IP;
2898 param.param_hdr.length = htons(paramlen + addr_param_len);
2901 sctp_addto_chunk(retval, paramlen, ¶m);
2902 sctp_addto_chunk(retval, addr_param_len, &addr_param);
2908 * 3.2.4 Set Primary IP Address
2910 * 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
2911 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2912 * | Type =0xC004 | Length = Variable |
2913 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2914 * | ASCONF-Request Correlation ID |
2915 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2916 * | Address Parameter |
2917 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2919 * Create an ASCONF chunk with Set Primary IP address parameter.
2921 struct sctp_chunk *sctp_make_asconf_set_prim(struct sctp_association *asoc,
2922 union sctp_addr *addr)
2924 sctp_addip_param_t param;
2925 struct sctp_chunk *retval;
2926 int len = sizeof(param);
2927 union sctp_addr_param addrparam;
2929 struct sctp_af *af = sctp_get_af_specific(addr->v4.sin_family);
2931 addrlen = af->to_addr_param(addr, &addrparam);
2936 /* Create the chunk and make asconf header. */
2937 retval = sctp_make_asconf(asoc, addr, len);
2941 param.param_hdr.type = SCTP_PARAM_SET_PRIMARY;
2942 param.param_hdr.length = htons(len);
2945 sctp_addto_chunk(retval, sizeof(param), ¶m);
2946 sctp_addto_chunk(retval, addrlen, &addrparam);
2951 /* ADDIP 3.1.2 Address Configuration Acknowledgement Chunk (ASCONF-ACK)
2953 * 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
2954 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2955 * | Type = 0x80 | Chunk Flags | Chunk Length |
2956 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2958 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2959 * | ASCONF Parameter Response#1 |
2960 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2964 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2965 * | ASCONF Parameter Response#N |
2966 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2968 * Create an ASCONF_ACK chunk with enough space for the parameter responses.
2970 static struct sctp_chunk *sctp_make_asconf_ack(const struct sctp_association *asoc,
2971 __u32 serial, int vparam_len)
2973 sctp_addiphdr_t asconf;
2974 struct sctp_chunk *retval;
2975 int length = sizeof(asconf) + vparam_len;
2977 /* Create the chunk. */
2978 retval = sctp_make_control(asoc, SCTP_CID_ASCONF_ACK, 0, length,
2983 asconf.serial = htonl(serial);
2985 retval->subh.addip_hdr =
2986 sctp_addto_chunk(retval, sizeof(asconf), &asconf);
2991 /* Add response parameters to an ASCONF_ACK chunk. */
2992 static void sctp_add_asconf_response(struct sctp_chunk *chunk, __be32 crr_id,
2993 __be16 err_code, sctp_addip_param_t *asconf_param)
2995 sctp_addip_param_t ack_param;
2996 sctp_errhdr_t err_param;
2997 int asconf_param_len = 0;
2998 int err_param_len = 0;
2999 __be16 response_type;
3001 if (SCTP_ERROR_NO_ERROR == err_code) {
3002 response_type = SCTP_PARAM_SUCCESS_REPORT;
3004 response_type = SCTP_PARAM_ERR_CAUSE;
3005 err_param_len = sizeof(err_param);
3008 ntohs(asconf_param->param_hdr.length);
3011 /* Add Success Indication or Error Cause Indication parameter. */
3012 ack_param.param_hdr.type = response_type;
3013 ack_param.param_hdr.length = htons(sizeof(ack_param) +
3016 ack_param.crr_id = crr_id;
3017 sctp_addto_chunk(chunk, sizeof(ack_param), &ack_param);
3019 if (SCTP_ERROR_NO_ERROR == err_code)
3022 /* Add Error Cause parameter. */
3023 err_param.cause = err_code;
3024 err_param.length = htons(err_param_len + asconf_param_len);
3025 sctp_addto_chunk(chunk, err_param_len, &err_param);
3027 /* Add the failed TLV copied from ASCONF chunk. */
3029 sctp_addto_chunk(chunk, asconf_param_len, asconf_param);
3032 /* Process a asconf parameter. */
3033 static __be16 sctp_process_asconf_param(struct sctp_association *asoc,
3034 struct sctp_chunk *asconf,
3035 sctp_addip_param_t *asconf_param)
3037 struct sctp_transport *peer;
3039 union sctp_addr addr;
3040 union sctp_addr_param *addr_param;
3042 addr_param = (void *)asconf_param + sizeof(sctp_addip_param_t);
3044 if (asconf_param->param_hdr.type != SCTP_PARAM_ADD_IP &&
3045 asconf_param->param_hdr.type != SCTP_PARAM_DEL_IP &&
3046 asconf_param->param_hdr.type != SCTP_PARAM_SET_PRIMARY)
3047 return SCTP_ERROR_UNKNOWN_PARAM;
3049 switch (addr_param->p.type) {
3050 case SCTP_PARAM_IPV6_ADDRESS:
3051 if (!asoc->peer.ipv6_address)
3052 return SCTP_ERROR_DNS_FAILED;
3054 case SCTP_PARAM_IPV4_ADDRESS:
3055 if (!asoc->peer.ipv4_address)
3056 return SCTP_ERROR_DNS_FAILED;
3059 return SCTP_ERROR_DNS_FAILED;
3062 af = sctp_get_af_specific(param_type2af(addr_param->p.type));
3064 return SCTP_ERROR_DNS_FAILED;
3066 af->from_addr_param(&addr, addr_param, htons(asoc->peer.port), 0);
3068 /* ADDIP 4.2.1 This parameter MUST NOT contain a broadcast
3069 * or multicast address.
3070 * (note: wildcard is permitted and requires special handling so
3071 * make sure we check for that)
3073 if (!af->is_any(&addr) && !af->addr_valid(&addr, NULL, asconf->skb))
3074 return SCTP_ERROR_DNS_FAILED;
3076 switch (asconf_param->param_hdr.type) {
3077 case SCTP_PARAM_ADD_IP:
3079 * If the address 0.0.0.0 or ::0 is provided, the source
3080 * address of the packet MUST be added.
3082 if (af->is_any(&addr))
3083 memcpy(&addr, &asconf->source, sizeof(addr));
3085 /* ADDIP 4.3 D9) If an endpoint receives an ADD IP address
3086 * request and does not have the local resources to add this
3087 * new address to the association, it MUST return an Error
3088 * Cause TLV set to the new error code 'Operation Refused
3089 * Due to Resource Shortage'.
3092 peer = sctp_assoc_add_peer(asoc, &addr, GFP_ATOMIC, SCTP_UNCONFIRMED);
3094 return SCTP_ERROR_RSRC_LOW;
3096 /* Start the heartbeat timer. */
3097 sctp_transport_reset_hb_timer(peer);
3098 asoc->new_transport = peer;
3100 case SCTP_PARAM_DEL_IP:
3101 /* ADDIP 4.3 D7) If a request is received to delete the
3102 * last remaining IP address of a peer endpoint, the receiver
3103 * MUST send an Error Cause TLV with the error cause set to the
3104 * new error code 'Request to Delete Last Remaining IP Address'.
3106 if (asoc->peer.transport_count == 1)
3107 return SCTP_ERROR_DEL_LAST_IP;
3109 /* ADDIP 4.3 D8) If a request is received to delete an IP
3110 * address which is also the source address of the IP packet
3111 * which contained the ASCONF chunk, the receiver MUST reject
3112 * this request. To reject the request the receiver MUST send
3113 * an Error Cause TLV set to the new error code 'Request to
3114 * Delete Source IP Address'
3116 if (sctp_cmp_addr_exact(&asconf->source, &addr))
3117 return SCTP_ERROR_DEL_SRC_IP;
3120 * If the address 0.0.0.0 or ::0 is provided, all
3121 * addresses of the peer except the source address of the
3122 * packet MUST be deleted.
3124 if (af->is_any(&addr)) {
3125 sctp_assoc_set_primary(asoc, asconf->transport);
3126 sctp_assoc_del_nonprimary_peers(asoc,
3128 return SCTP_ERROR_NO_ERROR;
3131 /* If the address is not part of the association, the
3132 * ASCONF-ACK with Error Cause Indication Parameter
3133 * which including cause of Unresolvable Address should
3136 peer = sctp_assoc_lookup_paddr(asoc, &addr);
3138 return SCTP_ERROR_DNS_FAILED;
3140 sctp_assoc_rm_peer(asoc, peer);
3142 case SCTP_PARAM_SET_PRIMARY:
3143 /* ADDIP Section 4.2.4
3144 * If the address 0.0.0.0 or ::0 is provided, the receiver
3145 * MAY mark the source address of the packet as its
3148 if (af->is_any(&addr))
3149 memcpy(&addr.v4, sctp_source(asconf), sizeof(addr));
3151 peer = sctp_assoc_lookup_paddr(asoc, &addr);
3153 return SCTP_ERROR_DNS_FAILED;
3155 sctp_assoc_set_primary(asoc, peer);
3159 return SCTP_ERROR_NO_ERROR;
3162 /* Verify the ASCONF packet before we process it. */
3163 bool sctp_verify_asconf(const struct sctp_association *asoc,
3164 struct sctp_chunk *chunk, bool addr_param_needed,
3165 struct sctp_paramhdr **errp)
3167 sctp_addip_chunk_t *addip = (sctp_addip_chunk_t *) chunk->chunk_hdr;
3168 union sctp_params param;
3169 bool addr_param_seen = false;
3171 sctp_walk_params(param, addip, addip_hdr.params) {
3172 size_t length = ntohs(param.p->length);
3175 switch (param.p->type) {
3176 case SCTP_PARAM_ERR_CAUSE:
3178 case SCTP_PARAM_IPV4_ADDRESS:
3179 if (length != sizeof(sctp_ipv4addr_param_t))
3181 /* ensure there is only one addr param and it's in the
3182 * beginning of addip_hdr params, or we reject it.
3184 if (param.v != addip->addip_hdr.params)
3186 addr_param_seen = true;
3188 case SCTP_PARAM_IPV6_ADDRESS:
3189 if (length != sizeof(sctp_ipv6addr_param_t))
3191 if (param.v != addip->addip_hdr.params)
3193 addr_param_seen = true;
3195 case SCTP_PARAM_ADD_IP:
3196 case SCTP_PARAM_DEL_IP:
3197 case SCTP_PARAM_SET_PRIMARY:
3198 /* In ASCONF chunks, these need to be first. */
3199 if (addr_param_needed && !addr_param_seen)
3201 length = ntohs(param.addip->param_hdr.length);
3202 if (length < sizeof(sctp_addip_param_t) +
3203 sizeof(sctp_paramhdr_t))
3206 case SCTP_PARAM_SUCCESS_REPORT:
3207 case SCTP_PARAM_ADAPTATION_LAYER_IND:
3208 if (length != sizeof(sctp_addip_param_t))
3212 /* This is unkown to us, reject! */
3217 /* Remaining sanity checks. */
3218 if (addr_param_needed && !addr_param_seen)
3220 if (!addr_param_needed && addr_param_seen)
3222 if (param.v != chunk->chunk_end)
3228 /* Process an incoming ASCONF chunk with the next expected serial no. and
3229 * return an ASCONF_ACK chunk to be sent in response.
3231 struct sctp_chunk *sctp_process_asconf(struct sctp_association *asoc,
3232 struct sctp_chunk *asconf)
3234 sctp_addip_chunk_t *addip = (sctp_addip_chunk_t *) asconf->chunk_hdr;
3235 bool all_param_pass = true;
3236 union sctp_params param;
3237 sctp_addiphdr_t *hdr;
3238 union sctp_addr_param *addr_param;
3239 sctp_addip_param_t *asconf_param;
3240 struct sctp_chunk *asconf_ack;
3246 chunk_len = ntohs(asconf->chunk_hdr->length) - sizeof(sctp_chunkhdr_t);
3247 hdr = (sctp_addiphdr_t *)asconf->skb->data;
3248 serial = ntohl(hdr->serial);
3250 /* Skip the addiphdr and store a pointer to address parameter. */
3251 length = sizeof(sctp_addiphdr_t);
3252 addr_param = (union sctp_addr_param *)(asconf->skb->data + length);
3253 chunk_len -= length;
3255 /* Skip the address parameter and store a pointer to the first
3258 length = ntohs(addr_param->p.length);
3259 asconf_param = (void *)addr_param + length;
3260 chunk_len -= length;
3262 /* create an ASCONF_ACK chunk.
3263 * Based on the definitions of parameters, we know that the size of
3264 * ASCONF_ACK parameters are less than or equal to the fourfold of ASCONF
3267 asconf_ack = sctp_make_asconf_ack(asoc, serial, chunk_len * 4);
3271 /* Process the TLVs contained within the ASCONF chunk. */
3272 sctp_walk_params(param, addip, addip_hdr.params) {
3273 /* Skip preceeding address parameters. */
3274 if (param.p->type == SCTP_PARAM_IPV4_ADDRESS ||
3275 param.p->type == SCTP_PARAM_IPV6_ADDRESS)
3278 err_code = sctp_process_asconf_param(asoc, asconf,
3281 * If an error response is received for a TLV parameter,
3282 * all TLVs with no response before the failed TLV are
3283 * considered successful if not reported. All TLVs after
3284 * the failed response are considered unsuccessful unless
3285 * a specific success indication is present for the parameter.
3287 if (err_code != SCTP_ERROR_NO_ERROR)
3288 all_param_pass = false;
3289 if (!all_param_pass)
3290 sctp_add_asconf_response(asconf_ack, param.addip->crr_id,
3291 err_code, param.addip);
3293 /* ADDIP 4.3 D11) When an endpoint receiving an ASCONF to add
3294 * an IP address sends an 'Out of Resource' in its response, it
3295 * MUST also fail any subsequent add or delete requests bundled
3298 if (err_code == SCTP_ERROR_RSRC_LOW)
3302 asoc->peer.addip_serial++;
3304 /* If we are sending a new ASCONF_ACK hold a reference to it in assoc
3305 * after freeing the reference to old asconf ack if any.
3308 sctp_chunk_hold(asconf_ack);
3309 list_add_tail(&asconf_ack->transmitted_list,
3310 &asoc->asconf_ack_list);
3316 /* Process a asconf parameter that is successfully acked. */
3317 static void sctp_asconf_param_success(struct sctp_association *asoc,
3318 sctp_addip_param_t *asconf_param)
3321 union sctp_addr addr;
3322 struct sctp_bind_addr *bp = &asoc->base.bind_addr;
3323 union sctp_addr_param *addr_param;
3324 struct sctp_transport *transport;
3325 struct sctp_sockaddr_entry *saddr;
3327 addr_param = (void *)asconf_param + sizeof(sctp_addip_param_t);
3329 /* We have checked the packet before, so we do not check again. */
3330 af = sctp_get_af_specific(param_type2af(addr_param->p.type));
3331 af->from_addr_param(&addr, addr_param, htons(bp->port), 0);
3333 switch (asconf_param->param_hdr.type) {
3334 case SCTP_PARAM_ADD_IP:
3335 /* This is always done in BH context with a socket lock
3336 * held, so the list can not change.
3339 list_for_each_entry(saddr, &bp->address_list, list) {
3340 if (sctp_cmp_addr_exact(&saddr->a, &addr))
3341 saddr->state = SCTP_ADDR_SRC;
3344 list_for_each_entry(transport, &asoc->peer.transport_addr_list,
3346 dst_release(transport->dst);
3347 transport->dst = NULL;
3350 case SCTP_PARAM_DEL_IP:
3352 sctp_del_bind_addr(bp, &addr);
3353 if (asoc->asconf_addr_del_pending != NULL &&
3354 sctp_cmp_addr_exact(asoc->asconf_addr_del_pending, &addr)) {
3355 kfree(asoc->asconf_addr_del_pending);
3356 asoc->asconf_addr_del_pending = NULL;
3359 list_for_each_entry(transport, &asoc->peer.transport_addr_list,
3361 dst_release(transport->dst);
3362 transport->dst = NULL;
3370 /* Get the corresponding ASCONF response error code from the ASCONF_ACK chunk
3371 * for the given asconf parameter. If there is no response for this parameter,
3372 * return the error code based on the third argument 'no_err'.
3374 * A7) If an error response is received for a TLV parameter, all TLVs with no
3375 * response before the failed TLV are considered successful if not reported.
3376 * All TLVs after the failed response are considered unsuccessful unless a
3377 * specific success indication is present for the parameter.
3379 static __be16 sctp_get_asconf_response(struct sctp_chunk *asconf_ack,
3380 sctp_addip_param_t *asconf_param,
3383 sctp_addip_param_t *asconf_ack_param;
3384 sctp_errhdr_t *err_param;
3390 err_code = SCTP_ERROR_NO_ERROR;
3392 err_code = SCTP_ERROR_REQ_REFUSED;
3394 asconf_ack_len = ntohs(asconf_ack->chunk_hdr->length) -
3395 sizeof(sctp_chunkhdr_t);
3397 /* Skip the addiphdr from the asconf_ack chunk and store a pointer to
3398 * the first asconf_ack parameter.
3400 length = sizeof(sctp_addiphdr_t);
3401 asconf_ack_param = (sctp_addip_param_t *)(asconf_ack->skb->data +
3403 asconf_ack_len -= length;
3405 while (asconf_ack_len > 0) {
3406 if (asconf_ack_param->crr_id == asconf_param->crr_id) {
3407 switch (asconf_ack_param->param_hdr.type) {
3408 case SCTP_PARAM_SUCCESS_REPORT:
3409 return SCTP_ERROR_NO_ERROR;
3410 case SCTP_PARAM_ERR_CAUSE:
3411 length = sizeof(sctp_addip_param_t);
3412 err_param = (void *)asconf_ack_param + length;
3413 asconf_ack_len -= length;
3414 if (asconf_ack_len > 0)
3415 return err_param->cause;
3417 return SCTP_ERROR_INV_PARAM;
3420 return SCTP_ERROR_INV_PARAM;
3424 length = ntohs(asconf_ack_param->param_hdr.length);
3425 asconf_ack_param = (void *)asconf_ack_param + length;
3426 asconf_ack_len -= length;
3432 /* Process an incoming ASCONF_ACK chunk against the cached last ASCONF chunk. */
3433 int sctp_process_asconf_ack(struct sctp_association *asoc,
3434 struct sctp_chunk *asconf_ack)
3436 struct sctp_chunk *asconf = asoc->addip_last_asconf;
3437 union sctp_addr_param *addr_param;
3438 sctp_addip_param_t *asconf_param;
3440 int asconf_len = asconf->skb->len;
3441 int all_param_pass = 0;
3444 __be16 err_code = SCTP_ERROR_NO_ERROR;
3446 /* Skip the chunkhdr and addiphdr from the last asconf sent and store
3447 * a pointer to address parameter.
3449 length = sizeof(sctp_addip_chunk_t);
3450 addr_param = (union sctp_addr_param *)(asconf->skb->data + length);
3451 asconf_len -= length;
3453 /* Skip the address parameter in the last asconf sent and store a
3454 * pointer to the first asconf parameter.
3456 length = ntohs(addr_param->p.length);
3457 asconf_param = (void *)addr_param + length;
3458 asconf_len -= length;
3461 * A8) If there is no response(s) to specific TLV parameter(s), and no
3462 * failures are indicated, then all request(s) are considered
3465 if (asconf_ack->skb->len == sizeof(sctp_addiphdr_t))
3468 /* Process the TLVs contained in the last sent ASCONF chunk. */
3469 while (asconf_len > 0) {
3471 err_code = SCTP_ERROR_NO_ERROR;
3473 err_code = sctp_get_asconf_response(asconf_ack,
3476 if (no_err && (SCTP_ERROR_NO_ERROR != err_code))
3481 case SCTP_ERROR_NO_ERROR:
3482 sctp_asconf_param_success(asoc, asconf_param);
3485 case SCTP_ERROR_RSRC_LOW:
3489 case SCTP_ERROR_UNKNOWN_PARAM:
3490 /* Disable sending this type of asconf parameter in
3493 asoc->peer.addip_disabled_mask |=
3494 asconf_param->param_hdr.type;
3497 case SCTP_ERROR_REQ_REFUSED:
3498 case SCTP_ERROR_DEL_LAST_IP:
3499 case SCTP_ERROR_DEL_SRC_IP:
3504 /* Skip the processed asconf parameter and move to the next
3507 length = ntohs(asconf_param->param_hdr.length);
3508 asconf_param = (void *)asconf_param + length;
3509 asconf_len -= length;
3512 if (no_err && asoc->src_out_of_asoc_ok) {
3513 asoc->src_out_of_asoc_ok = 0;
3514 sctp_transport_immediate_rtx(asoc->peer.primary_path);
3517 /* Free the cached last sent asconf chunk. */
3518 list_del_init(&asconf->transmitted_list);
3519 sctp_chunk_free(asconf);
3520 asoc->addip_last_asconf = NULL;
3525 /* Make a FWD TSN chunk. */
3526 struct sctp_chunk *sctp_make_fwdtsn(const struct sctp_association *asoc,
3527 __u32 new_cum_tsn, size_t nstreams,
3528 struct sctp_fwdtsn_skip *skiplist)
3530 struct sctp_chunk *retval = NULL;
3531 struct sctp_fwdtsn_hdr ftsn_hdr;
3532 struct sctp_fwdtsn_skip skip;
3536 hint = (nstreams + 1) * sizeof(__u32);
3538 retval = sctp_make_control(asoc, SCTP_CID_FWD_TSN, 0, hint, GFP_ATOMIC);
3543 ftsn_hdr.new_cum_tsn = htonl(new_cum_tsn);
3544 retval->subh.fwdtsn_hdr =
3545 sctp_addto_chunk(retval, sizeof(ftsn_hdr), &ftsn_hdr);
3547 for (i = 0; i < nstreams; i++) {
3548 skip.stream = skiplist[i].stream;
3549 skip.ssn = skiplist[i].ssn;
3550 sctp_addto_chunk(retval, sizeof(skip), &skip);