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Vlad Yasevich60c778b2008-01-11 09:57:09 -05001/* SCTP kernel implementation
Linus Torvalds1da177e2005-04-16 15:20:36 -07002 * (C) Copyright IBM Corp. 2001, 2004
3 * Copyright (c) 1999-2000 Cisco, Inc.
4 * Copyright (c) 1999-2001 Motorola, Inc.
5 * Copyright (c) 2001 Intel Corp.
6 * Copyright (c) 2001 La Monte H.P. Yarroll
7 *
Vlad Yasevich60c778b2008-01-11 09:57:09 -05008 * This file is part of the SCTP kernel implementation
Linus Torvalds1da177e2005-04-16 15:20:36 -07009 *
10 * This module provides the abstraction for an SCTP association.
11 *
Vlad Yasevich60c778b2008-01-11 09:57:09 -050012 * This SCTP implementation is free software;
Linus Torvalds1da177e2005-04-16 15:20:36 -070013 * you can redistribute it and/or modify it under the terms of
14 * the GNU General Public License as published by
15 * the Free Software Foundation; either version 2, or (at your option)
16 * any later version.
17 *
Vlad Yasevich60c778b2008-01-11 09:57:09 -050018 * This SCTP implementation is distributed in the hope that it
Linus Torvalds1da177e2005-04-16 15:20:36 -070019 * will be useful, but WITHOUT ANY WARRANTY; without even the implied
20 * ************************
21 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
22 * See the GNU General Public License for more details.
23 *
24 * You should have received a copy of the GNU General Public License
25 * along with GNU CC; see the file COPYING. If not, write to
26 * the Free Software Foundation, 59 Temple Place - Suite 330,
27 * Boston, MA 02111-1307, USA.
28 *
29 * Please send any bug reports or fixes you make to the
30 * email address(es):
31 * lksctp developers <lksctp-developers@lists.sourceforge.net>
32 *
33 * Or submit a bug report through the following website:
34 * http://www.sf.net/projects/lksctp
35 *
36 * Written or modified by:
37 * La Monte H.P. Yarroll <piggy@acm.org>
38 * Karl Knutson <karl@athena.chicago.il.us>
39 * Jon Grimm <jgrimm@us.ibm.com>
40 * Xingang Guo <xingang.guo@intel.com>
41 * Hui Huang <hui.huang@nokia.com>
42 * Sridhar Samudrala <sri@us.ibm.com>
43 * Daisy Chang <daisyc@us.ibm.com>
44 * Ryan Layer <rmlayer@us.ibm.com>
45 * Kevin Gao <kevin.gao@intel.com>
46 *
47 * Any bugs reported given to us we will try to fix... any fixes shared will
48 * be incorporated into the next SCTP release.
49 */
50
Joe Perches145ce502010-08-24 13:21:08 +000051#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
52
Linus Torvalds1da177e2005-04-16 15:20:36 -070053#include <linux/types.h>
54#include <linux/fcntl.h>
55#include <linux/poll.h>
56#include <linux/init.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070057
58#include <linux/slab.h>
59#include <linux/in.h>
60#include <net/ipv6.h>
61#include <net/sctp/sctp.h>
62#include <net/sctp/sm.h>
63
64/* Forward declarations for internal functions. */
David Howellsc4028952006-11-22 14:57:56 +000065static void sctp_assoc_bh_rcv(struct work_struct *work);
Vlad Yasevicha08de642007-12-20 14:11:47 -080066static void sctp_assoc_free_asconf_acks(struct sctp_association *asoc);
Wei Yongjun8b4472c2011-05-24 21:48:02 +000067static void sctp_assoc_free_asconf_queue(struct sctp_association *asoc);
Linus Torvalds1da177e2005-04-16 15:20:36 -070068
Vlad Yasevich48143262009-11-23 15:54:01 -050069/* Keep track of the new idr low so that we don't re-use association id
70 * numbers too fast. It is protected by they idr spin lock is in the
71 * range of 1 - INT_MAX.
72 */
73static u32 idr_low = 1;
74
Linus Torvalds1da177e2005-04-16 15:20:36 -070075
76/* 1st Level Abstractions. */
77
78/* Initialize a new association from provided memory. */
79static struct sctp_association *sctp_association_init(struct sctp_association *asoc,
80 const struct sctp_endpoint *ep,
81 const struct sock *sk,
82 sctp_scope_t scope,
Al Virodd0fc662005-10-07 07:46:04 +010083 gfp_t gfp)
Linus Torvalds1da177e2005-04-16 15:20:36 -070084{
85 struct sctp_sock *sp;
86 int i;
Vlad Yasevicha29a5bd2007-09-16 19:31:35 -070087 sctp_paramhdr_t *p;
88 int err;
Linus Torvalds1da177e2005-04-16 15:20:36 -070089
90 /* Retrieve the SCTP per socket area. */
91 sp = sctp_sk((struct sock *)sk);
92
Linus Torvalds1da177e2005-04-16 15:20:36 -070093 /* Discarding const is appropriate here. */
94 asoc->ep = (struct sctp_endpoint *)ep;
95 sctp_endpoint_hold(asoc->ep);
96
97 /* Hold the sock. */
98 asoc->base.sk = (struct sock *)sk;
99 sock_hold(asoc->base.sk);
100
101 /* Initialize the common base substructure. */
102 asoc->base.type = SCTP_EP_TYPE_ASSOCIATION;
103
104 /* Initialize the object handling fields. */
105 atomic_set(&asoc->base.refcnt, 1);
106 asoc->base.dead = 0;
107 asoc->base.malloced = 0;
108
109 /* Initialize the bind addr area. */
110 sctp_bind_addr_init(&asoc->base.bind_addr, ep->base.bind_addr.port);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700111
112 asoc->state = SCTP_STATE_CLOSED;
113
114 /* Set these values from the socket values, a conversion between
115 * millsecons to seconds/microseconds must also be done.
116 */
117 asoc->cookie_life.tv_sec = sp->assocparams.sasoc_cookie_life / 1000;
118 asoc->cookie_life.tv_usec = (sp->assocparams.sasoc_cookie_life % 1000)
119 * 1000;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700120 asoc->frag_point = 0;
Vlad Yasevichf68b2e02009-09-04 18:21:00 -0400121 asoc->user_frag = sp->user_frag;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700122
123 /* Set the association max_retrans and RTO values from the
124 * socket values.
125 */
126 asoc->max_retrans = sp->assocparams.sasoc_asocmaxrxt;
127 asoc->rto_initial = msecs_to_jiffies(sp->rtoinfo.srto_initial);
128 asoc->rto_max = msecs_to_jiffies(sp->rtoinfo.srto_max);
129 asoc->rto_min = msecs_to_jiffies(sp->rtoinfo.srto_min);
130
131 asoc->overall_error_count = 0;
132
Frank Filz52ccb8e2005-12-22 11:36:46 -0800133 /* Initialize the association's heartbeat interval based on the
134 * sock configured value.
135 */
136 asoc->hbinterval = msecs_to_jiffies(sp->hbinterval);
137
138 /* Initialize path max retrans value. */
139 asoc->pathmaxrxt = sp->pathmaxrxt;
140
141 /* Initialize default path MTU. */
142 asoc->pathmtu = sp->pathmtu;
143
144 /* Set association default SACK delay */
145 asoc->sackdelay = msecs_to_jiffies(sp->sackdelay);
Wei Yongjund364d922008-05-09 15:13:26 -0700146 asoc->sackfreq = sp->sackfreq;
Frank Filz52ccb8e2005-12-22 11:36:46 -0800147
148 /* Set the association default flags controlling
149 * Heartbeat, SACK delay, and Path MTU Discovery.
150 */
151 asoc->param_flags = sp->param_flags;
152
Linus Torvalds1da177e2005-04-16 15:20:36 -0700153 /* Initialize the maximum mumber of new data packets that can be sent
154 * in a burst.
155 */
Vlad Yasevich70331572007-03-23 11:34:36 -0700156 asoc->max_burst = sp->max_burst;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700157
Vladislav Yasevich1e7d3d92005-11-11 16:06:16 -0800158 /* initialize association timers */
159 asoc->timeouts[SCTP_EVENT_TIMEOUT_NONE] = 0;
160 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_COOKIE] = asoc->rto_initial;
161 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_INIT] = asoc->rto_initial;
162 asoc->timeouts[SCTP_EVENT_TIMEOUT_T2_SHUTDOWN] = asoc->rto_initial;
163 asoc->timeouts[SCTP_EVENT_TIMEOUT_T3_RTX] = 0;
164 asoc->timeouts[SCTP_EVENT_TIMEOUT_T4_RTO] = 0;
165
166 /* sctpimpguide Section 2.12.2
167 * If the 'T5-shutdown-guard' timer is used, it SHOULD be set to the
168 * recommended value of 5 times 'RTO.Max'.
169 */
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +0900170 asoc->timeouts[SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD]
Vladislav Yasevich1e7d3d92005-11-11 16:06:16 -0800171 = 5 * asoc->rto_max;
172
173 asoc->timeouts[SCTP_EVENT_TIMEOUT_HEARTBEAT] = 0;
Frank Filz52ccb8e2005-12-22 11:36:46 -0800174 asoc->timeouts[SCTP_EVENT_TIMEOUT_SACK] = asoc->sackdelay;
Vladislav Yasevich1e7d3d92005-11-11 16:06:16 -0800175 asoc->timeouts[SCTP_EVENT_TIMEOUT_AUTOCLOSE] =
Andrei Pelinescu-Onciulda85b732009-11-23 15:54:01 -0500176 (unsigned long)sp->autoclose * HZ;
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +0900177
Uwe Kleine-König421f91d2010-06-11 12:17:00 +0200178 /* Initializes the timers */
Pavel Emelyanovb24b8a22008-01-23 21:20:07 -0800179 for (i = SCTP_EVENT_TIMEOUT_NONE; i < SCTP_NUM_TIMEOUT_TYPES; ++i)
180 setup_timer(&asoc->timers[i], sctp_timer_events[i],
181 (unsigned long)asoc);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700182
183 /* Pull default initialization values from the sock options.
184 * Note: This assumes that the values have already been
185 * validated in the sock.
186 */
187 asoc->c.sinit_max_instreams = sp->initmsg.sinit_max_instreams;
188 asoc->c.sinit_num_ostreams = sp->initmsg.sinit_num_ostreams;
189 asoc->max_init_attempts = sp->initmsg.sinit_max_attempts;
190
191 asoc->max_init_timeo =
192 msecs_to_jiffies(sp->initmsg.sinit_max_init_timeo);
193
194 /* Allocate storage for the ssnmap after the inbound and outbound
195 * streams have been negotiated during Init.
196 */
197 asoc->ssnmap = NULL;
198
199 /* Set the local window size for receive.
200 * This is also the rcvbuf space per association.
201 * RFC 6 - A SCTP receiver MUST be able to receive a minimum of
202 * 1500 bytes in one SCTP packet.
203 */
Neil Horman049b3ff2005-11-11 16:08:24 -0800204 if ((sk->sk_rcvbuf/2) < SCTP_DEFAULT_MINWINDOW)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700205 asoc->rwnd = SCTP_DEFAULT_MINWINDOW;
206 else
Neil Horman049b3ff2005-11-11 16:08:24 -0800207 asoc->rwnd = sk->sk_rcvbuf/2;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700208
209 asoc->a_rwnd = asoc->rwnd;
210
211 asoc->rwnd_over = 0;
Vlad Yasevich4d3c46e2009-09-04 18:20:59 -0400212 asoc->rwnd_press = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700213
214 /* Use my own max window until I learn something better. */
215 asoc->peer.rwnd = SCTP_DEFAULT_MAXWINDOW;
216
217 /* Set the sndbuf size for transmit. */
218 asoc->sndbuf_used = 0;
219
Neil Horman049b3ff2005-11-11 16:08:24 -0800220 /* Initialize the receive memory counter */
221 atomic_set(&asoc->rmem_alloc, 0);
222
Linus Torvalds1da177e2005-04-16 15:20:36 -0700223 init_waitqueue_head(&asoc->wait);
224
225 asoc->c.my_vtag = sctp_generate_tag(ep);
226 asoc->peer.i.init_tag = 0; /* INIT needs a vtag of 0. */
227 asoc->c.peer_vtag = 0;
228 asoc->c.my_ttag = 0;
229 asoc->c.peer_ttag = 0;
230 asoc->c.my_port = ep->base.bind_addr.port;
231
232 asoc->c.initial_tsn = sctp_generate_tsn(ep);
233
234 asoc->next_tsn = asoc->c.initial_tsn;
235
236 asoc->ctsn_ack_point = asoc->next_tsn - 1;
237 asoc->adv_peer_ack_point = asoc->ctsn_ack_point;
238 asoc->highest_sacked = asoc->ctsn_ack_point;
239 asoc->last_cwr_tsn = asoc->ctsn_ack_point;
240 asoc->unack_data = 0;
241
Linus Torvalds1da177e2005-04-16 15:20:36 -0700242 /* ADDIP Section 4.1 Asconf Chunk Procedures
243 *
244 * When an endpoint has an ASCONF signaled change to be sent to the
245 * remote endpoint it should do the following:
246 * ...
247 * A2) a serial number should be assigned to the chunk. The serial
248 * number SHOULD be a monotonically increasing number. The serial
249 * numbers SHOULD be initialized at the start of the
250 * association to the same value as the initial TSN.
251 */
252 asoc->addip_serial = asoc->c.initial_tsn;
253
David S. Miller79af02c2005-07-08 21:47:49 -0700254 INIT_LIST_HEAD(&asoc->addip_chunk_list);
Vlad Yasevicha08de642007-12-20 14:11:47 -0800255 INIT_LIST_HEAD(&asoc->asconf_ack_list);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700256
257 /* Make an empty list of remote transport addresses. */
258 INIT_LIST_HEAD(&asoc->peer.transport_addr_list);
Frank Filz3f7a87d2005-06-20 13:14:57 -0700259 asoc->peer.transport_count = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700260
261 /* RFC 2960 5.1 Normal Establishment of an Association
262 *
263 * After the reception of the first data chunk in an
264 * association the endpoint must immediately respond with a
265 * sack to acknowledge the data chunk. Subsequent
266 * acknowledgements should be done as described in Section
267 * 6.2.
268 *
269 * [We implement this by telling a new association that it
270 * already received one packet.]
271 */
272 asoc->peer.sack_needed = 1;
Wei Yongjund364d922008-05-09 15:13:26 -0700273 asoc->peer.sack_cnt = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700274
Vlad Yasevich73d9c4f2007-10-24 17:24:26 -0400275 /* Assume that the peer will tell us if he recognizes ASCONF
276 * as part of INIT exchange.
277 * The sctp_addip_noauth option is there for backward compatibilty
278 * and will revert old behavior.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700279 */
Vlad Yasevich88799fe2007-10-24 17:24:23 -0400280 asoc->peer.asconf_capable = 0;
Vlad Yasevich73d9c4f2007-10-24 17:24:26 -0400281 if (sctp_addip_noauth)
282 asoc->peer.asconf_capable = 1;
Michio Honda8a07eb02011-04-26 20:19:36 +0900283 asoc->asconf_addr_del_pending = NULL;
284 asoc->src_out_of_asoc_ok = 0;
Michio Honda6af29cc2011-06-16 17:14:34 +0900285 asoc->new_transport = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700286
287 /* Create an input queue. */
288 sctp_inq_init(&asoc->base.inqueue);
David Howellsc4028952006-11-22 14:57:56 +0000289 sctp_inq_set_th_handler(&asoc->base.inqueue, sctp_assoc_bh_rcv);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700290
291 /* Create an output queue. */
292 sctp_outq_init(asoc, &asoc->outqueue);
293
294 if (!sctp_ulpq_init(&asoc->ulpq, asoc))
295 goto fail_init;
296
Vlad Yasevich8e1ee182008-10-08 14:18:39 -0700297 memset(&asoc->peer.tsn_map, 0, sizeof(struct sctp_tsnmap));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700298
299 asoc->need_ecne = 0;
300
301 asoc->assoc_id = 0;
302
303 /* Assume that peer would support both address types unless we are
304 * told otherwise.
305 */
306 asoc->peer.ipv4_address = 1;
Wei Yongjuna2c39582009-04-07 16:35:11 +0800307 if (asoc->base.sk->sk_family == PF_INET6)
308 asoc->peer.ipv6_address = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700309 INIT_LIST_HEAD(&asoc->asocs);
310
311 asoc->autoclose = sp->autoclose;
312
313 asoc->default_stream = sp->default_stream;
314 asoc->default_ppid = sp->default_ppid;
315 asoc->default_flags = sp->default_flags;
316 asoc->default_context = sp->default_context;
317 asoc->default_timetolive = sp->default_timetolive;
Ivan Skytte Jorgensen6ab792f2006-12-13 16:34:22 -0800318 asoc->default_rcv_context = sp->default_rcv_context;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700319
Vlad Yasevicha29a5bd2007-09-16 19:31:35 -0700320 /* AUTH related initializations */
321 INIT_LIST_HEAD(&asoc->endpoint_shared_keys);
322 err = sctp_auth_asoc_copy_shkeys(ep, asoc, gfp);
323 if (err)
324 goto fail_init;
325
326 asoc->active_key_id = ep->active_key_id;
327 asoc->asoc_shared_key = NULL;
328
329 asoc->default_hmac_id = 0;
330 /* Save the hmacs and chunks list into this association */
331 if (ep->auth_hmacs_list)
332 memcpy(asoc->c.auth_hmacs, ep->auth_hmacs_list,
333 ntohs(ep->auth_hmacs_list->param_hdr.length));
334 if (ep->auth_chunk_list)
335 memcpy(asoc->c.auth_chunks, ep->auth_chunk_list,
336 ntohs(ep->auth_chunk_list->param_hdr.length));
337
338 /* Get the AUTH random number for this association */
339 p = (sctp_paramhdr_t *)asoc->c.auth_random;
340 p->type = SCTP_PARAM_RANDOM;
341 p->length = htons(sizeof(sctp_paramhdr_t) + SCTP_AUTH_RANDOM_LENGTH);
342 get_random_bytes(p+1, SCTP_AUTH_RANDOM_LENGTH);
343
Linus Torvalds1da177e2005-04-16 15:20:36 -0700344 return asoc;
345
346fail_init:
347 sctp_endpoint_put(asoc->ep);
348 sock_put(asoc->base.sk);
349 return NULL;
350}
351
352/* Allocate and initialize a new association */
353struct sctp_association *sctp_association_new(const struct sctp_endpoint *ep,
354 const struct sock *sk,
Alexey Dobriyan3182cd842005-07-11 20:57:47 -0700355 sctp_scope_t scope,
Al Virodd0fc662005-10-07 07:46:04 +0100356 gfp_t gfp)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700357{
358 struct sctp_association *asoc;
359
360 asoc = t_new(struct sctp_association, gfp);
361 if (!asoc)
362 goto fail;
363
364 if (!sctp_association_init(asoc, ep, sk, scope, gfp))
365 goto fail_init;
366
367 asoc->base.malloced = 1;
368 SCTP_DBG_OBJCNT_INC(assoc);
Frank Filz3f7a87d2005-06-20 13:14:57 -0700369 SCTP_DEBUG_PRINTK("Created asoc %p\n", asoc);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700370
371 return asoc;
372
373fail_init:
374 kfree(asoc);
375fail:
376 return NULL;
377}
378
379/* Free this association if possible. There may still be users, so
380 * the actual deallocation may be delayed.
381 */
382void sctp_association_free(struct sctp_association *asoc)
383{
384 struct sock *sk = asoc->base.sk;
385 struct sctp_transport *transport;
386 struct list_head *pos, *temp;
387 int i;
388
Vlad Yasevichde76e692006-10-30 18:55:11 -0800389 /* Only real associations count against the endpoint, so
390 * don't bother for if this is a temporary association.
391 */
392 if (!asoc->temp) {
393 list_del(&asoc->asocs);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700394
Vlad Yasevichde76e692006-10-30 18:55:11 -0800395 /* Decrement the backlog value for a TCP-style listening
396 * socket.
397 */
398 if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING))
399 sk->sk_ack_backlog--;
400 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700401
402 /* Mark as dead, so other users can know this structure is
403 * going away.
404 */
405 asoc->base.dead = 1;
406
407 /* Dispose of any data lying around in the outqueue. */
408 sctp_outq_free(&asoc->outqueue);
409
410 /* Dispose of any pending messages for the upper layer. */
411 sctp_ulpq_free(&asoc->ulpq);
412
413 /* Dispose of any pending chunks on the inqueue. */
414 sctp_inq_free(&asoc->base.inqueue);
415
Vlad Yasevich8e1ee182008-10-08 14:18:39 -0700416 sctp_tsnmap_free(&asoc->peer.tsn_map);
417
Linus Torvalds1da177e2005-04-16 15:20:36 -0700418 /* Free ssnmap storage. */
419 sctp_ssnmap_free(asoc->ssnmap);
420
421 /* Clean up the bound address list. */
422 sctp_bind_addr_free(&asoc->base.bind_addr);
423
424 /* Do we need to go through all of our timers and
425 * delete them? To be safe we will try to delete all, but we
426 * should be able to go through and make a guess based
427 * on our state.
428 */
429 for (i = SCTP_EVENT_TIMEOUT_NONE; i < SCTP_NUM_TIMEOUT_TYPES; ++i) {
430 if (timer_pending(&asoc->timers[i]) &&
431 del_timer(&asoc->timers[i]))
432 sctp_association_put(asoc);
433 }
434
435 /* Free peer's cached cookie. */
Jesper Juhla51482b2005-11-08 09:41:34 -0800436 kfree(asoc->peer.cookie);
Vlad Yasevich730fc3d2007-09-16 19:32:11 -0700437 kfree(asoc->peer.peer_random);
438 kfree(asoc->peer.peer_chunks);
439 kfree(asoc->peer.peer_hmacs);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700440
441 /* Release the transport structures. */
442 list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
443 transport = list_entry(pos, struct sctp_transport, transports);
444 list_del(pos);
445 sctp_transport_free(transport);
446 }
447
Frank Filz3f7a87d2005-06-20 13:14:57 -0700448 asoc->peer.transport_count = 0;
449
Wei Yongjuna000c012011-05-29 23:23:36 +0000450 sctp_asconf_queue_teardown(asoc);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700451
Michio Honda8a07eb02011-04-26 20:19:36 +0900452 /* Free pending address space being deleted */
453 if (asoc->asconf_addr_del_pending != NULL)
454 kfree(asoc->asconf_addr_del_pending);
455
Vlad Yasevicha29a5bd2007-09-16 19:31:35 -0700456 /* AUTH - Free the endpoint shared keys */
457 sctp_auth_destroy_keys(&asoc->endpoint_shared_keys);
458
459 /* AUTH - Free the association shared key */
460 sctp_auth_key_put(asoc->asoc_shared_key);
461
Linus Torvalds1da177e2005-04-16 15:20:36 -0700462 sctp_association_put(asoc);
463}
464
465/* Cleanup and free up an association. */
466static void sctp_association_destroy(struct sctp_association *asoc)
467{
468 SCTP_ASSERT(asoc->base.dead, "Assoc is not dead", return);
469
470 sctp_endpoint_put(asoc->ep);
471 sock_put(asoc->base.sk);
472
473 if (asoc->assoc_id != 0) {
474 spin_lock_bh(&sctp_assocs_id_lock);
475 idr_remove(&sctp_assocs_id, asoc->assoc_id);
476 spin_unlock_bh(&sctp_assocs_id_lock);
477 }
478
Ilpo Järvinen547b7922008-07-25 21:43:18 -0700479 WARN_ON(atomic_read(&asoc->rmem_alloc));
Neil Horman049b3ff2005-11-11 16:08:24 -0800480
Linus Torvalds1da177e2005-04-16 15:20:36 -0700481 if (asoc->base.malloced) {
482 kfree(asoc);
483 SCTP_DBG_OBJCNT_DEC(assoc);
484 }
485}
486
487/* Change the primary destination address for the peer. */
488void sctp_assoc_set_primary(struct sctp_association *asoc,
489 struct sctp_transport *transport)
490{
Vlad Yasevich319fa2a2008-06-16 17:00:29 -0700491 int changeover = 0;
492
493 /* it's a changeover only if we already have a primary path
494 * that we are changing
495 */
496 if (asoc->peer.primary_path != NULL &&
497 asoc->peer.primary_path != transport)
498 changeover = 1 ;
499
Linus Torvalds1da177e2005-04-16 15:20:36 -0700500 asoc->peer.primary_path = transport;
501
502 /* Set a default msg_name for events. */
503 memcpy(&asoc->peer.primary_addr, &transport->ipaddr,
504 sizeof(union sctp_addr));
505
506 /* If the primary path is changing, assume that the
507 * user wants to use this new path.
508 */
Sridhar Samudralaad8fec12006-07-21 14:48:50 -0700509 if ((transport->state == SCTP_ACTIVE) ||
510 (transport->state == SCTP_UNKNOWN))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700511 asoc->peer.active_path = transport;
512
513 /*
514 * SFR-CACC algorithm:
515 * Upon the receipt of a request to change the primary
516 * destination address, on the data structure for the new
517 * primary destination, the sender MUST do the following:
518 *
519 * 1) If CHANGEOVER_ACTIVE is set, then there was a switch
520 * to this destination address earlier. The sender MUST set
521 * CYCLING_CHANGEOVER to indicate that this switch is a
522 * double switch to the same destination address.
Vlad Yaseviche0e9db12009-11-23 15:53:57 -0500523 *
524 * Really, only bother is we have data queued or outstanding on
525 * the association.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700526 */
Vlad Yaseviche0e9db12009-11-23 15:53:57 -0500527 if (!asoc->outqueue.outstanding_bytes && !asoc->outqueue.out_qlen)
528 return;
529
Linus Torvalds1da177e2005-04-16 15:20:36 -0700530 if (transport->cacc.changeover_active)
Vlad Yasevich319fa2a2008-06-16 17:00:29 -0700531 transport->cacc.cycling_changeover = changeover;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700532
533 /* 2) The sender MUST set CHANGEOVER_ACTIVE to indicate that
534 * a changeover has occurred.
535 */
Vlad Yasevich319fa2a2008-06-16 17:00:29 -0700536 transport->cacc.changeover_active = changeover;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700537
538 /* 3) The sender MUST store the next TSN to be sent in
539 * next_tsn_at_change.
540 */
541 transport->cacc.next_tsn_at_change = asoc->next_tsn;
542}
543
Frank Filz3f7a87d2005-06-20 13:14:57 -0700544/* Remove a transport from an association. */
545void sctp_assoc_rm_peer(struct sctp_association *asoc,
546 struct sctp_transport *peer)
547{
548 struct list_head *pos;
549 struct sctp_transport *transport;
550
551 SCTP_DEBUG_PRINTK_IPADDR("sctp_assoc_rm_peer:association %p addr: ",
552 " port: %d\n",
553 asoc,
554 (&peer->ipaddr),
Al Virob3f5b3b2006-11-20 17:22:43 -0800555 ntohs(peer->ipaddr.v4.sin_port));
Frank Filz3f7a87d2005-06-20 13:14:57 -0700556
557 /* If we are to remove the current retran_path, update it
558 * to the next peer before removing this peer from the list.
559 */
560 if (asoc->peer.retran_path == peer)
561 sctp_assoc_update_retran_path(asoc);
562
563 /* Remove this peer from the list. */
564 list_del(&peer->transports);
565
566 /* Get the first transport of asoc. */
567 pos = asoc->peer.transport_addr_list.next;
568 transport = list_entry(pos, struct sctp_transport, transports);
569
570 /* Update any entries that match the peer to be deleted. */
571 if (asoc->peer.primary_path == peer)
572 sctp_assoc_set_primary(asoc, transport);
573 if (asoc->peer.active_path == peer)
574 asoc->peer.active_path = transport;
Wei Yongjun9494c7c2011-04-12 15:22:22 +0000575 if (asoc->peer.retran_path == peer)
576 asoc->peer.retran_path = transport;
Frank Filz3f7a87d2005-06-20 13:14:57 -0700577 if (asoc->peer.last_data_from == peer)
578 asoc->peer.last_data_from = transport;
579
580 /* If we remove the transport an INIT was last sent to, set it to
581 * NULL. Combined with the update of the retran path above, this
582 * will cause the next INIT to be sent to the next available
583 * transport, maintaining the cycle.
584 */
585 if (asoc->init_last_sent_to == peer)
586 asoc->init_last_sent_to = NULL;
587
Wei Yongjun6345b192009-04-26 23:13:35 +0800588 /* If we remove the transport an SHUTDOWN was last sent to, set it
589 * to NULL. Combined with the update of the retran path above, this
590 * will cause the next SHUTDOWN to be sent to the next available
591 * transport, maintaining the cycle.
592 */
593 if (asoc->shutdown_last_sent_to == peer)
594 asoc->shutdown_last_sent_to = NULL;
595
Wei Yongjun10a43ce2009-04-26 23:14:42 +0800596 /* If we remove the transport an ASCONF was last sent to, set it to
597 * NULL.
598 */
599 if (asoc->addip_last_asconf &&
600 asoc->addip_last_asconf->transport == peer)
601 asoc->addip_last_asconf->transport = NULL;
602
Vlad Yasevich31b02e12009-09-04 18:21:00 -0400603 /* If we have something on the transmitted list, we have to
604 * save it off. The best place is the active path.
605 */
606 if (!list_empty(&peer->transmitted)) {
607 struct sctp_transport *active = asoc->peer.active_path;
608 struct sctp_chunk *ch;
609
610 /* Reset the transport of each chunk on this list */
611 list_for_each_entry(ch, &peer->transmitted,
612 transmitted_list) {
613 ch->transport = NULL;
614 ch->rtt_in_progress = 0;
615 }
616
617 list_splice_tail_init(&peer->transmitted,
618 &active->transmitted);
619
620 /* Start a T3 timer here in case it wasn't running so
621 * that these migrated packets have a chance to get
622 * retrnasmitted.
623 */
624 if (!timer_pending(&active->T3_rtx_timer))
625 if (!mod_timer(&active->T3_rtx_timer,
626 jiffies + active->rto))
627 sctp_transport_hold(active);
628 }
629
Frank Filz3f7a87d2005-06-20 13:14:57 -0700630 asoc->peer.transport_count--;
631
632 sctp_transport_free(peer);
633}
634
Linus Torvalds1da177e2005-04-16 15:20:36 -0700635/* Add a transport address to an association. */
636struct sctp_transport *sctp_assoc_add_peer(struct sctp_association *asoc,
637 const union sctp_addr *addr,
Al Virodd0fc662005-10-07 07:46:04 +0100638 const gfp_t gfp,
Frank Filz3f7a87d2005-06-20 13:14:57 -0700639 const int peer_state)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700640{
641 struct sctp_transport *peer;
642 struct sctp_sock *sp;
643 unsigned short port;
644
645 sp = sctp_sk(asoc->base.sk);
646
647 /* AF_INET and AF_INET6 share common port field. */
Al Viro4bdf4b52006-11-20 17:10:20 -0800648 port = ntohs(addr->v4.sin_port);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700649
Frank Filz3f7a87d2005-06-20 13:14:57 -0700650 SCTP_DEBUG_PRINTK_IPADDR("sctp_assoc_add_peer:association %p addr: ",
Sridhar Samudralaad8fec12006-07-21 14:48:50 -0700651 " port: %d state:%d\n",
Frank Filz3f7a87d2005-06-20 13:14:57 -0700652 asoc,
653 addr,
Al Viro4bdf4b52006-11-20 17:10:20 -0800654 port,
Sridhar Samudralaad8fec12006-07-21 14:48:50 -0700655 peer_state);
Frank Filz3f7a87d2005-06-20 13:14:57 -0700656
Linus Torvalds1da177e2005-04-16 15:20:36 -0700657 /* Set the port if it has not been set yet. */
658 if (0 == asoc->peer.port)
659 asoc->peer.port = port;
660
661 /* Check to see if this is a duplicate. */
662 peer = sctp_assoc_lookup_paddr(asoc, addr);
Frank Filz3f7a87d2005-06-20 13:14:57 -0700663 if (peer) {
Vlad Yasevichadd52372008-09-18 16:28:27 -0700664 /* An UNKNOWN state is only set on transports added by
665 * user in sctp_connectx() call. Such transports should be
666 * considered CONFIRMED per RFC 4960, Section 5.4.
667 */
Sridhar Samudralaad8fec12006-07-21 14:48:50 -0700668 if (peer->state == SCTP_UNKNOWN) {
Vlad Yasevichadd52372008-09-18 16:28:27 -0700669 peer->state = SCTP_ACTIVE;
Sridhar Samudralaad8fec12006-07-21 14:48:50 -0700670 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700671 return peer;
Frank Filz3f7a87d2005-06-20 13:14:57 -0700672 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700673
674 peer = sctp_transport_new(addr, gfp);
675 if (!peer)
676 return NULL;
677
678 sctp_transport_set_owner(peer, asoc);
679
Frank Filz52ccb8e2005-12-22 11:36:46 -0800680 /* Initialize the peer's heartbeat interval based on the
681 * association configured value.
682 */
683 peer->hbinterval = asoc->hbinterval;
684
685 /* Set the path max_retrans. */
686 peer->pathmaxrxt = asoc->pathmaxrxt;
687
688 /* Initialize the peer's SACK delay timeout based on the
689 * association configured value.
690 */
691 peer->sackdelay = asoc->sackdelay;
Wei Yongjund364d922008-05-09 15:13:26 -0700692 peer->sackfreq = asoc->sackfreq;
Frank Filz52ccb8e2005-12-22 11:36:46 -0800693
694 /* Enable/disable heartbeat, SACK delay, and path MTU discovery
695 * based on association setting.
696 */
697 peer->param_flags = asoc->param_flags;
698
Vlad Yasevich8da645e2009-09-04 18:21:01 -0400699 sctp_transport_route(peer, NULL, sp);
700
Linus Torvalds1da177e2005-04-16 15:20:36 -0700701 /* Initialize the pmtu of the transport. */
Vlad Yasevich8da645e2009-09-04 18:21:01 -0400702 if (peer->param_flags & SPP_PMTUD_DISABLE) {
703 if (asoc->pathmtu)
704 peer->pathmtu = asoc->pathmtu;
705 else
706 peer->pathmtu = SCTP_DEFAULT_MAXSEGMENT;
707 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700708
709 /* If this is the first transport addr on this association,
710 * initialize the association PMTU to the peer's PMTU.
711 * If not and the current association PMTU is higher than the new
712 * peer's PMTU, reset the association PMTU to the new peer's PMTU.
713 */
Frank Filz52ccb8e2005-12-22 11:36:46 -0800714 if (asoc->pathmtu)
715 asoc->pathmtu = min_t(int, peer->pathmtu, asoc->pathmtu);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700716 else
Frank Filz52ccb8e2005-12-22 11:36:46 -0800717 asoc->pathmtu = peer->pathmtu;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700718
719 SCTP_DEBUG_PRINTK("sctp_assoc_add_peer:association %p PMTU set to "
Frank Filz52ccb8e2005-12-22 11:36:46 -0800720 "%d\n", asoc, asoc->pathmtu);
Florian Westphal6d0ccba2008-07-18 23:04:39 -0700721 peer->pmtu_pending = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700722
Vlad Yasevichf68b2e02009-09-04 18:21:00 -0400723 asoc->frag_point = sctp_frag_point(asoc, asoc->pathmtu);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700724
725 /* The asoc->peer.port might not be meaningful yet, but
726 * initialize the packet structure anyway.
727 */
728 sctp_packet_init(&peer->packet, peer, asoc->base.bind_addr.port,
729 asoc->peer.port);
730
731 /* 7.2.1 Slow-Start
732 *
733 * o The initial cwnd before DATA transmission or after a sufficiently
734 * long idle period MUST be set to
735 * min(4*MTU, max(2*MTU, 4380 bytes))
736 *
737 * o The initial value of ssthresh MAY be arbitrarily high
738 * (for example, implementations MAY use the size of the
739 * receiver advertised window).
740 */
Frank Filz52ccb8e2005-12-22 11:36:46 -0800741 peer->cwnd = min(4*asoc->pathmtu, max_t(__u32, 2*asoc->pathmtu, 4380));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700742
743 /* At this point, we may not have the receiver's advertised window,
744 * so initialize ssthresh to the default value and it will be set
745 * later when we process the INIT.
746 */
747 peer->ssthresh = SCTP_DEFAULT_MAXWINDOW;
748
749 peer->partial_bytes_acked = 0;
750 peer->flight_size = 0;
Vlad Yasevich46d5a802009-11-23 15:54:00 -0500751 peer->burst_limited = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700752
Linus Torvalds1da177e2005-04-16 15:20:36 -0700753 /* Set the transport's RTO.initial value */
754 peer->rto = asoc->rto_initial;
755
Frank Filz3f7a87d2005-06-20 13:14:57 -0700756 /* Set the peer's active state. */
757 peer->state = peer_state;
758
Linus Torvalds1da177e2005-04-16 15:20:36 -0700759 /* Attach the remote transport to our asoc. */
760 list_add_tail(&peer->transports, &asoc->peer.transport_addr_list);
Frank Filz3f7a87d2005-06-20 13:14:57 -0700761 asoc->peer.transport_count++;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700762
763 /* If we do not yet have a primary path, set one. */
764 if (!asoc->peer.primary_path) {
765 sctp_assoc_set_primary(asoc, peer);
766 asoc->peer.retran_path = peer;
767 }
768
Vlad Yasevichfbdf5012010-04-30 22:39:26 -0400769 if (asoc->peer.active_path == asoc->peer.retran_path &&
770 peer->state != SCTP_UNCONFIRMED) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700771 asoc->peer.retran_path = peer;
Frank Filz3f7a87d2005-06-20 13:14:57 -0700772 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700773
774 return peer;
775}
776
777/* Delete a transport address from an association. */
778void sctp_assoc_del_peer(struct sctp_association *asoc,
779 const union sctp_addr *addr)
780{
781 struct list_head *pos;
782 struct list_head *temp;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700783 struct sctp_transport *transport;
784
785 list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
786 transport = list_entry(pos, struct sctp_transport, transports);
787 if (sctp_cmp_addr_exact(addr, &transport->ipaddr)) {
Frank Filz3f7a87d2005-06-20 13:14:57 -0700788 /* Do book keeping for removing the peer and free it. */
789 sctp_assoc_rm_peer(asoc, transport);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700790 break;
791 }
792 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700793}
794
795/* Lookup a transport by address. */
796struct sctp_transport *sctp_assoc_lookup_paddr(
797 const struct sctp_association *asoc,
798 const union sctp_addr *address)
799{
800 struct sctp_transport *t;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700801
802 /* Cycle through all transports searching for a peer address. */
803
Robert P. J. Day9dbc15f2008-04-12 18:54:24 -0700804 list_for_each_entry(t, &asoc->peer.transport_addr_list,
805 transports) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700806 if (sctp_cmp_addr_exact(address, &t->ipaddr))
807 return t;
808 }
809
810 return NULL;
811}
812
Vlad Yasevich42e30bf2007-12-20 14:08:56 -0800813/* Remove all transports except a give one */
814void sctp_assoc_del_nonprimary_peers(struct sctp_association *asoc,
815 struct sctp_transport *primary)
816{
817 struct sctp_transport *temp;
818 struct sctp_transport *t;
819
820 list_for_each_entry_safe(t, temp, &asoc->peer.transport_addr_list,
821 transports) {
822 /* if the current transport is not the primary one, delete it */
823 if (t != primary)
824 sctp_assoc_rm_peer(asoc, t);
825 }
Vlad Yasevich42e30bf2007-12-20 14:08:56 -0800826}
827
Linus Torvalds1da177e2005-04-16 15:20:36 -0700828/* Engage in transport control operations.
829 * Mark the transport up or down and send a notification to the user.
830 * Select and update the new active and retran paths.
831 */
832void sctp_assoc_control_transport(struct sctp_association *asoc,
833 struct sctp_transport *transport,
834 sctp_transport_cmd_t command,
835 sctp_sn_error_t error)
836{
837 struct sctp_transport *t = NULL;
838 struct sctp_transport *first;
839 struct sctp_transport *second;
840 struct sctp_ulpevent *event;
Al Viro0906e202006-11-20 17:03:01 -0800841 struct sockaddr_storage addr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700842 int spc_state = 0;
843
844 /* Record the transition on the transport. */
845 switch (command) {
846 case SCTP_TRANSPORT_UP:
Vlad Yasevich1ae41142007-03-23 11:32:26 -0700847 /* If we are moving from UNCONFIRMED state due
848 * to heartbeat success, report the SCTP_ADDR_CONFIRMED
849 * state to the user, otherwise report SCTP_ADDR_AVAILABLE.
850 */
851 if (SCTP_UNCONFIRMED == transport->state &&
852 SCTP_HEARTBEAT_SUCCESS == error)
853 spc_state = SCTP_ADDR_CONFIRMED;
854 else
855 spc_state = SCTP_ADDR_AVAILABLE;
Frank Filz3f7a87d2005-06-20 13:14:57 -0700856 transport->state = SCTP_ACTIVE;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700857 break;
858
859 case SCTP_TRANSPORT_DOWN:
Vlad Yasevich40187882009-06-23 11:28:05 -0400860 /* If the transport was never confirmed, do not transition it
861 * to inactive state. Also, release the cached route since
862 * there may be a better route next time.
Vlad Yasevichcc756892007-08-24 19:30:25 +0900863 */
864 if (transport->state != SCTP_UNCONFIRMED)
865 transport->state = SCTP_INACTIVE;
Vlad Yasevich40187882009-06-23 11:28:05 -0400866 else {
867 dst_release(transport->dst);
868 transport->dst = NULL;
869 }
Vlad Yasevichcc756892007-08-24 19:30:25 +0900870
Linus Torvalds1da177e2005-04-16 15:20:36 -0700871 spc_state = SCTP_ADDR_UNREACHABLE;
872 break;
873
874 default:
875 return;
Stephen Hemminger3ff50b72007-04-20 17:09:22 -0700876 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700877
878 /* Generate and send a SCTP_PEER_ADDR_CHANGE notification to the
879 * user.
880 */
Al Viro0906e202006-11-20 17:03:01 -0800881 memset(&addr, 0, sizeof(struct sockaddr_storage));
Al Viro8cec6b82006-11-20 17:23:01 -0800882 memcpy(&addr, &transport->ipaddr, transport->af_specific->sockaddr_len);
Al Viro0906e202006-11-20 17:03:01 -0800883 event = sctp_ulpevent_make_peer_addr_change(asoc, &addr,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700884 0, spc_state, error, GFP_ATOMIC);
885 if (event)
886 sctp_ulpq_tail_event(&asoc->ulpq, event);
887
888 /* Select new active and retran paths. */
889
890 /* Look for the two most recently used active transports.
891 *
892 * This code produces the wrong ordering whenever jiffies
893 * rolls over, but we still get usable transports, so we don't
894 * worry about it.
895 */
896 first = NULL; second = NULL;
897
Robert P. J. Day9dbc15f2008-04-12 18:54:24 -0700898 list_for_each_entry(t, &asoc->peer.transport_addr_list,
899 transports) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700900
Sridhar Samudralaad8fec12006-07-21 14:48:50 -0700901 if ((t->state == SCTP_INACTIVE) ||
902 (t->state == SCTP_UNCONFIRMED))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700903 continue;
904 if (!first || t->last_time_heard > first->last_time_heard) {
905 second = first;
906 first = t;
907 }
908 if (!second || t->last_time_heard > second->last_time_heard)
909 second = t;
910 }
911
912 /* RFC 2960 6.4 Multi-Homed SCTP Endpoints
913 *
914 * By default, an endpoint should always transmit to the
915 * primary path, unless the SCTP user explicitly specifies the
916 * destination transport address (and possibly source
917 * transport address) to use.
918 *
919 * [If the primary is active but not most recent, bump the most
920 * recently used transport.]
921 */
Sridhar Samudralaad8fec12006-07-21 14:48:50 -0700922 if (((asoc->peer.primary_path->state == SCTP_ACTIVE) ||
923 (asoc->peer.primary_path->state == SCTP_UNKNOWN)) &&
Linus Torvalds1da177e2005-04-16 15:20:36 -0700924 first != asoc->peer.primary_path) {
925 second = first;
926 first = asoc->peer.primary_path;
927 }
928
929 /* If we failed to find a usable transport, just camp on the
930 * primary, even if it is inactive.
931 */
932 if (!first) {
933 first = asoc->peer.primary_path;
934 second = asoc->peer.primary_path;
935 }
936
937 /* Set the active and retran transports. */
938 asoc->peer.active_path = first;
939 asoc->peer.retran_path = second;
940}
941
942/* Hold a reference to an association. */
943void sctp_association_hold(struct sctp_association *asoc)
944{
945 atomic_inc(&asoc->base.refcnt);
946}
947
948/* Release a reference to an association and cleanup
949 * if there are no more references.
950 */
951void sctp_association_put(struct sctp_association *asoc)
952{
953 if (atomic_dec_and_test(&asoc->base.refcnt))
954 sctp_association_destroy(asoc);
955}
956
957/* Allocate the next TSN, Transmission Sequence Number, for the given
958 * association.
959 */
960__u32 sctp_association_get_next_tsn(struct sctp_association *asoc)
961{
962 /* From Section 1.6 Serial Number Arithmetic:
963 * Transmission Sequence Numbers wrap around when they reach
964 * 2**32 - 1. That is, the next TSN a DATA chunk MUST use
965 * after transmitting TSN = 2*32 - 1 is TSN = 0.
966 */
967 __u32 retval = asoc->next_tsn;
968 asoc->next_tsn++;
969 asoc->unack_data++;
970
971 return retval;
972}
973
974/* Compare two addresses to see if they match. Wildcard addresses
975 * only match themselves.
976 */
977int sctp_cmp_addr_exact(const union sctp_addr *ss1,
978 const union sctp_addr *ss2)
979{
980 struct sctp_af *af;
981
982 af = sctp_get_af_specific(ss1->sa.sa_family);
983 if (unlikely(!af))
984 return 0;
985
986 return af->cmp_addr(ss1, ss2);
987}
988
989/* Return an ecne chunk to get prepended to a packet.
990 * Note: We are sly and return a shared, prealloced chunk. FIXME:
991 * No we don't, but we could/should.
992 */
993struct sctp_chunk *sctp_get_ecne_prepend(struct sctp_association *asoc)
994{
995 struct sctp_chunk *chunk;
996
997 /* Send ECNE if needed.
998 * Not being able to allocate a chunk here is not deadly.
999 */
1000 if (asoc->need_ecne)
1001 chunk = sctp_make_ecne(asoc, asoc->last_ecne_tsn);
1002 else
1003 chunk = NULL;
1004
1005 return chunk;
1006}
1007
1008/*
1009 * Find which transport this TSN was sent on.
1010 */
1011struct sctp_transport *sctp_assoc_lookup_tsn(struct sctp_association *asoc,
1012 __u32 tsn)
1013{
1014 struct sctp_transport *active;
1015 struct sctp_transport *match;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001016 struct sctp_transport *transport;
1017 struct sctp_chunk *chunk;
Al Virodbc16db2006-11-20 17:01:42 -08001018 __be32 key = htonl(tsn);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001019
1020 match = NULL;
1021
1022 /*
1023 * FIXME: In general, find a more efficient data structure for
1024 * searching.
1025 */
1026
1027 /*
1028 * The general strategy is to search each transport's transmitted
1029 * list. Return which transport this TSN lives on.
1030 *
1031 * Let's be hopeful and check the active_path first.
1032 * Another optimization would be to know if there is only one
1033 * outbound path and not have to look for the TSN at all.
1034 *
1035 */
1036
1037 active = asoc->peer.active_path;
1038
Robert P. J. Day9dbc15f2008-04-12 18:54:24 -07001039 list_for_each_entry(chunk, &active->transmitted,
1040 transmitted_list) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001041
1042 if (key == chunk->subh.data_hdr->tsn) {
1043 match = active;
1044 goto out;
1045 }
1046 }
1047
1048 /* If not found, go search all the other transports. */
Robert P. J. Day9dbc15f2008-04-12 18:54:24 -07001049 list_for_each_entry(transport, &asoc->peer.transport_addr_list,
1050 transports) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001051
1052 if (transport == active)
1053 break;
Robert P. J. Day9dbc15f2008-04-12 18:54:24 -07001054 list_for_each_entry(chunk, &transport->transmitted,
1055 transmitted_list) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001056 if (key == chunk->subh.data_hdr->tsn) {
1057 match = transport;
1058 goto out;
1059 }
1060 }
1061 }
1062out:
1063 return match;
1064}
1065
1066/* Is this the association we are looking for? */
1067struct sctp_transport *sctp_assoc_is_match(struct sctp_association *asoc,
1068 const union sctp_addr *laddr,
1069 const union sctp_addr *paddr)
1070{
1071 struct sctp_transport *transport;
1072
Al Viroe2fcced2006-11-20 17:08:41 -08001073 if ((htons(asoc->base.bind_addr.port) == laddr->v4.sin_port) &&
1074 (htons(asoc->peer.port) == paddr->v4.sin_port)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001075 transport = sctp_assoc_lookup_paddr(asoc, paddr);
1076 if (!transport)
1077 goto out;
1078
1079 if (sctp_bind_addr_match(&asoc->base.bind_addr, laddr,
1080 sctp_sk(asoc->base.sk)))
1081 goto out;
1082 }
1083 transport = NULL;
1084
1085out:
Linus Torvalds1da177e2005-04-16 15:20:36 -07001086 return transport;
1087}
1088
1089/* Do delayed input processing. This is scheduled by sctp_rcv(). */
David Howellsc4028952006-11-22 14:57:56 +00001090static void sctp_assoc_bh_rcv(struct work_struct *work)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001091{
David Howellsc4028952006-11-22 14:57:56 +00001092 struct sctp_association *asoc =
1093 container_of(work, struct sctp_association,
1094 base.inqueue.immediate);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001095 struct sctp_endpoint *ep;
1096 struct sctp_chunk *chunk;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001097 struct sctp_inq *inqueue;
1098 int state;
1099 sctp_subtype_t subtype;
1100 int error = 0;
1101
1102 /* The association should be held so we should be safe. */
1103 ep = asoc->ep;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001104
1105 inqueue = &asoc->base.inqueue;
1106 sctp_association_hold(asoc);
1107 while (NULL != (chunk = sctp_inq_pop(inqueue))) {
1108 state = asoc->state;
1109 subtype = SCTP_ST_CHUNK(chunk->chunk_hdr->type);
1110
Vlad Yasevichbbd0d592007-10-03 17:51:34 -07001111 /* SCTP-AUTH, Section 6.3:
1112 * The receiver has a list of chunk types which it expects
1113 * to be received only after an AUTH-chunk. This list has
1114 * been sent to the peer during the association setup. It
1115 * MUST silently discard these chunks if they are not placed
1116 * after an AUTH chunk in the packet.
1117 */
1118 if (sctp_auth_recv_cid(subtype.chunk, asoc) && !chunk->auth)
1119 continue;
1120
Linus Torvalds1da177e2005-04-16 15:20:36 -07001121 /* Remember where the last DATA chunk came from so we
1122 * know where to send the SACK.
1123 */
1124 if (sctp_chunk_is_data(chunk))
1125 asoc->peer.last_data_from = chunk->transport;
1126 else
1127 SCTP_INC_STATS(SCTP_MIB_INCTRLCHUNKS);
1128
1129 if (chunk->transport)
1130 chunk->transport->last_time_heard = jiffies;
1131
1132 /* Run through the state machine. */
1133 error = sctp_do_sm(SCTP_EVENT_T_CHUNK, subtype,
1134 state, ep, asoc, chunk, GFP_ATOMIC);
1135
1136 /* Check to see if the association is freed in response to
1137 * the incoming chunk. If so, get out of the while loop.
1138 */
1139 if (asoc->base.dead)
1140 break;
1141
1142 /* If there is an error on chunk, discard this packet. */
1143 if (error && chunk)
1144 chunk->pdiscard = 1;
1145 }
1146 sctp_association_put(asoc);
1147}
1148
1149/* This routine moves an association from its old sk to a new sk. */
1150void sctp_assoc_migrate(struct sctp_association *assoc, struct sock *newsk)
1151{
1152 struct sctp_sock *newsp = sctp_sk(newsk);
1153 struct sock *oldsk = assoc->base.sk;
1154
1155 /* Delete the association from the old endpoint's list of
1156 * associations.
1157 */
1158 list_del_init(&assoc->asocs);
1159
1160 /* Decrement the backlog value for a TCP-style socket. */
1161 if (sctp_style(oldsk, TCP))
1162 oldsk->sk_ack_backlog--;
1163
1164 /* Release references to the old endpoint and the sock. */
1165 sctp_endpoint_put(assoc->ep);
1166 sock_put(assoc->base.sk);
1167
1168 /* Get a reference to the new endpoint. */
1169 assoc->ep = newsp->ep;
1170 sctp_endpoint_hold(assoc->ep);
1171
1172 /* Get a reference to the new sock. */
1173 assoc->base.sk = newsk;
1174 sock_hold(assoc->base.sk);
1175
1176 /* Add the association to the new endpoint's list of associations. */
1177 sctp_endpoint_add_asoc(newsp->ep, assoc);
1178}
1179
1180/* Update an association (possibly from unexpected COOKIE-ECHO processing). */
1181void sctp_assoc_update(struct sctp_association *asoc,
1182 struct sctp_association *new)
1183{
1184 struct sctp_transport *trans;
1185 struct list_head *pos, *temp;
1186
1187 /* Copy in new parameters of peer. */
1188 asoc->c = new->c;
1189 asoc->peer.rwnd = new->peer.rwnd;
1190 asoc->peer.sack_needed = new->peer.sack_needed;
1191 asoc->peer.i = new->peer.i;
Vlad Yasevich8e1ee182008-10-08 14:18:39 -07001192 sctp_tsnmap_init(&asoc->peer.tsn_map, SCTP_TSN_MAP_INITIAL,
1193 asoc->peer.i.initial_tsn, GFP_ATOMIC);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001194
1195 /* Remove any peer addresses not present in the new association. */
1196 list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
1197 trans = list_entry(pos, struct sctp_transport, transports);
Vlad Yasevich0c427492010-04-28 08:47:19 +00001198 if (!sctp_assoc_lookup_paddr(new, &trans->ipaddr)) {
1199 sctp_assoc_rm_peer(asoc, trans);
1200 continue;
1201 }
Vlad Yasevich749bf922007-03-19 17:02:30 -07001202
1203 if (asoc->state >= SCTP_STATE_ESTABLISHED)
1204 sctp_transport_reset(trans);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001205 }
1206
1207 /* If the case is A (association restart), use
1208 * initial_tsn as next_tsn. If the case is B, use
1209 * current next_tsn in case data sent to peer
1210 * has been discarded and needs retransmission.
1211 */
1212 if (asoc->state >= SCTP_STATE_ESTABLISHED) {
1213 asoc->next_tsn = new->next_tsn;
1214 asoc->ctsn_ack_point = new->ctsn_ack_point;
1215 asoc->adv_peer_ack_point = new->adv_peer_ack_point;
1216
1217 /* Reinitialize SSN for both local streams
1218 * and peer's streams.
1219 */
1220 sctp_ssnmap_clear(asoc->ssnmap);
1221
Vlad Yasevich0b58a812007-03-19 17:01:17 -07001222 /* Flush the ULP reassembly and ordered queue.
1223 * Any data there will now be stale and will
1224 * cause problems.
1225 */
1226 sctp_ulpq_flush(&asoc->ulpq);
1227
Vlad Yasevich749bf922007-03-19 17:02:30 -07001228 /* reset the overall association error count so
1229 * that the restarted association doesn't get torn
1230 * down on the next retransmission timer.
1231 */
1232 asoc->overall_error_count = 0;
1233
Linus Torvalds1da177e2005-04-16 15:20:36 -07001234 } else {
1235 /* Add any peer addresses from the new association. */
Robert P. J. Day9dbc15f2008-04-12 18:54:24 -07001236 list_for_each_entry(trans, &new->peer.transport_addr_list,
1237 transports) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001238 if (!sctp_assoc_lookup_paddr(asoc, &trans->ipaddr))
1239 sctp_assoc_add_peer(asoc, &trans->ipaddr,
Sridhar Samudralaad8fec12006-07-21 14:48:50 -07001240 GFP_ATOMIC, trans->state);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001241 }
1242
1243 asoc->ctsn_ack_point = asoc->next_tsn - 1;
1244 asoc->adv_peer_ack_point = asoc->ctsn_ack_point;
1245 if (!asoc->ssnmap) {
1246 /* Move the ssnmap. */
1247 asoc->ssnmap = new->ssnmap;
1248 new->ssnmap = NULL;
1249 }
Vlad Yasevich07d93962007-05-04 13:55:27 -07001250
1251 if (!asoc->assoc_id) {
1252 /* get a new association id since we don't have one
1253 * yet.
1254 */
1255 sctp_assoc_set_id(asoc, GFP_ATOMIC);
1256 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001257 }
Vlad Yasevicha29a5bd2007-09-16 19:31:35 -07001258
Vlad Yasevich730fc3d2007-09-16 19:32:11 -07001259 /* SCTP-AUTH: Save the peer parameters from the new assocaitions
1260 * and also move the association shared keys over
1261 */
1262 kfree(asoc->peer.peer_random);
1263 asoc->peer.peer_random = new->peer.peer_random;
1264 new->peer.peer_random = NULL;
1265
1266 kfree(asoc->peer.peer_chunks);
1267 asoc->peer.peer_chunks = new->peer.peer_chunks;
1268 new->peer.peer_chunks = NULL;
1269
1270 kfree(asoc->peer.peer_hmacs);
1271 asoc->peer.peer_hmacs = new->peer.peer_hmacs;
1272 new->peer.peer_hmacs = NULL;
1273
1274 sctp_auth_key_put(asoc->asoc_shared_key);
1275 sctp_auth_asoc_init_active_key(asoc, GFP_ATOMIC);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001276}
1277
1278/* Update the retran path for sending a retransmitted packet.
1279 * Round-robin through the active transports, else round-robin
1280 * through the inactive transports as this is the next best thing
1281 * we can try.
1282 */
1283void sctp_assoc_update_retran_path(struct sctp_association *asoc)
1284{
1285 struct sctp_transport *t, *next;
1286 struct list_head *head = &asoc->peer.transport_addr_list;
1287 struct list_head *pos;
1288
Gui Jianfeng4141ddc2008-06-04 12:37:33 -07001289 if (asoc->peer.transport_count == 1)
1290 return;
1291
Linus Torvalds1da177e2005-04-16 15:20:36 -07001292 /* Find the next transport in a round-robin fashion. */
1293 t = asoc->peer.retran_path;
1294 pos = &t->transports;
1295 next = NULL;
1296
1297 while (1) {
1298 /* Skip the head. */
1299 if (pos->next == head)
1300 pos = head->next;
1301 else
1302 pos = pos->next;
1303
1304 t = list_entry(pos, struct sctp_transport, transports);
1305
Gui Jianfeng4141ddc2008-06-04 12:37:33 -07001306 /* We have exhausted the list, but didn't find any
1307 * other active transports. If so, use the next
1308 * transport.
1309 */
1310 if (t == asoc->peer.retran_path) {
1311 t = next;
1312 break;
1313 }
1314
Linus Torvalds1da177e2005-04-16 15:20:36 -07001315 /* Try to find an active transport. */
1316
Sridhar Samudralaad8fec12006-07-21 14:48:50 -07001317 if ((t->state == SCTP_ACTIVE) ||
1318 (t->state == SCTP_UNKNOWN)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001319 break;
1320 } else {
1321 /* Keep track of the next transport in case
1322 * we don't find any active transport.
1323 */
Vlad Yasevichfbdf5012010-04-30 22:39:26 -04001324 if (t->state != SCTP_UNCONFIRMED && !next)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001325 next = t;
1326 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001327 }
1328
Vlad Yasevichd598b162010-04-30 22:41:09 -04001329 if (t)
1330 asoc->peer.retran_path = t;
Vlad Yasevich25f7bf72011-04-12 15:20:48 +00001331 else
1332 t = asoc->peer.retran_path;
Frank Filz3f7a87d2005-06-20 13:14:57 -07001333
1334 SCTP_DEBUG_PRINTK_IPADDR("sctp_assoc_update_retran_path:association"
1335 " %p addr: ",
1336 " port: %d\n",
1337 asoc,
1338 (&t->ipaddr),
Al Virob3f5b3b2006-11-20 17:22:43 -08001339 ntohs(t->ipaddr.v4.sin_port));
Frank Filz3f7a87d2005-06-20 13:14:57 -07001340}
1341
Wei Yongjun9919b452009-05-12 21:52:51 +08001342/* Choose the transport for sending retransmit packet. */
1343struct sctp_transport *sctp_assoc_choose_alter_transport(
1344 struct sctp_association *asoc, struct sctp_transport *last_sent_to)
Frank Filz3f7a87d2005-06-20 13:14:57 -07001345{
Wei Yongjun9919b452009-05-12 21:52:51 +08001346 /* If this is the first time packet is sent, use the active path,
1347 * else use the retran path. If the last packet was sent over the
Frank Filz3f7a87d2005-06-20 13:14:57 -07001348 * retran path, update the retran path and use it.
1349 */
Wei Yongjun9919b452009-05-12 21:52:51 +08001350 if (!last_sent_to)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001351 return asoc->peer.active_path;
1352 else {
Wei Yongjun9919b452009-05-12 21:52:51 +08001353 if (last_sent_to == asoc->peer.retran_path)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001354 sctp_assoc_update_retran_path(asoc);
1355 return asoc->peer.retran_path;
1356 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001357}
1358
1359/* Update the association's pmtu and frag_point by going through all the
1360 * transports. This routine is called when a transport's PMTU has changed.
1361 */
1362void sctp_assoc_sync_pmtu(struct sctp_association *asoc)
1363{
1364 struct sctp_transport *t;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001365 __u32 pmtu = 0;
1366
1367 if (!asoc)
1368 return;
1369
1370 /* Get the lowest pmtu of all the transports. */
Robert P. J. Day9dbc15f2008-04-12 18:54:24 -07001371 list_for_each_entry(t, &asoc->peer.transport_addr_list,
1372 transports) {
Vlad Yasevich8a479492007-06-07 14:21:05 -04001373 if (t->pmtu_pending && t->dst) {
1374 sctp_transport_update_pmtu(t, dst_mtu(t->dst));
1375 t->pmtu_pending = 0;
1376 }
Frank Filz52ccb8e2005-12-22 11:36:46 -08001377 if (!pmtu || (t->pathmtu < pmtu))
1378 pmtu = t->pathmtu;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001379 }
1380
1381 if (pmtu) {
Frank Filz52ccb8e2005-12-22 11:36:46 -08001382 asoc->pathmtu = pmtu;
Vlad Yasevichf68b2e02009-09-04 18:21:00 -04001383 asoc->frag_point = sctp_frag_point(asoc, pmtu);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001384 }
1385
1386 SCTP_DEBUG_PRINTK("%s: asoc:%p, pmtu:%d, frag_point:%d\n",
Harvey Harrison0dc47872008-03-05 20:47:47 -08001387 __func__, asoc, asoc->pathmtu, asoc->frag_point);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001388}
1389
1390/* Should we send a SACK to update our peer? */
1391static inline int sctp_peer_needs_update(struct sctp_association *asoc)
1392{
1393 switch (asoc->state) {
1394 case SCTP_STATE_ESTABLISHED:
1395 case SCTP_STATE_SHUTDOWN_PENDING:
1396 case SCTP_STATE_SHUTDOWN_RECEIVED:
1397 case SCTP_STATE_SHUTDOWN_SENT:
1398 if ((asoc->rwnd > asoc->a_rwnd) &&
Vlad Yasevich90f2f532009-11-23 15:53:57 -05001399 ((asoc->rwnd - asoc->a_rwnd) >= max_t(__u32,
1400 (asoc->base.sk->sk_rcvbuf >> sctp_rwnd_upd_shift),
1401 asoc->pathmtu)))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001402 return 1;
1403 break;
1404 default:
1405 break;
1406 }
1407 return 0;
1408}
1409
1410/* Increase asoc's rwnd by len and send any window update SACK if needed. */
1411void sctp_assoc_rwnd_increase(struct sctp_association *asoc, unsigned len)
1412{
1413 struct sctp_chunk *sack;
1414 struct timer_list *timer;
1415
1416 if (asoc->rwnd_over) {
1417 if (asoc->rwnd_over >= len) {
1418 asoc->rwnd_over -= len;
1419 } else {
1420 asoc->rwnd += (len - asoc->rwnd_over);
1421 asoc->rwnd_over = 0;
1422 }
1423 } else {
1424 asoc->rwnd += len;
1425 }
1426
Vlad Yasevich4d3c46e2009-09-04 18:20:59 -04001427 /* If we had window pressure, start recovering it
1428 * once our rwnd had reached the accumulated pressure
1429 * threshold. The idea is to recover slowly, but up
1430 * to the initial advertised window.
1431 */
1432 if (asoc->rwnd_press && asoc->rwnd >= asoc->rwnd_press) {
1433 int change = min(asoc->pathmtu, asoc->rwnd_press);
1434 asoc->rwnd += change;
1435 asoc->rwnd_press -= change;
1436 }
1437
Linus Torvalds1da177e2005-04-16 15:20:36 -07001438 SCTP_DEBUG_PRINTK("%s: asoc %p rwnd increased by %d to (%u, %u) "
Harvey Harrison0dc47872008-03-05 20:47:47 -08001439 "- %u\n", __func__, asoc, len, asoc->rwnd,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001440 asoc->rwnd_over, asoc->a_rwnd);
1441
1442 /* Send a window update SACK if the rwnd has increased by at least the
1443 * minimum of the association's PMTU and half of the receive buffer.
1444 * The algorithm used is similar to the one described in
1445 * Section 4.2.3.3 of RFC 1122.
1446 */
1447 if (sctp_peer_needs_update(asoc)) {
1448 asoc->a_rwnd = asoc->rwnd;
1449 SCTP_DEBUG_PRINTK("%s: Sending window update SACK- asoc: %p "
Harvey Harrison0dc47872008-03-05 20:47:47 -08001450 "rwnd: %u a_rwnd: %u\n", __func__,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001451 asoc, asoc->rwnd, asoc->a_rwnd);
1452 sack = sctp_make_sack(asoc);
1453 if (!sack)
1454 return;
1455
1456 asoc->peer.sack_needed = 0;
1457
1458 sctp_outq_tail(&asoc->outqueue, sack);
1459
1460 /* Stop the SACK timer. */
1461 timer = &asoc->timers[SCTP_EVENT_TIMEOUT_SACK];
1462 if (timer_pending(timer) && del_timer(timer))
1463 sctp_association_put(asoc);
1464 }
1465}
1466
1467/* Decrease asoc's rwnd by len. */
1468void sctp_assoc_rwnd_decrease(struct sctp_association *asoc, unsigned len)
1469{
Vlad Yasevich4d3c46e2009-09-04 18:20:59 -04001470 int rx_count;
1471 int over = 0;
1472
Linus Torvalds1da177e2005-04-16 15:20:36 -07001473 SCTP_ASSERT(asoc->rwnd, "rwnd zero", return);
1474 SCTP_ASSERT(!asoc->rwnd_over, "rwnd_over not zero", return);
Vlad Yasevich4d3c46e2009-09-04 18:20:59 -04001475
1476 if (asoc->ep->rcvbuf_policy)
1477 rx_count = atomic_read(&asoc->rmem_alloc);
1478 else
1479 rx_count = atomic_read(&asoc->base.sk->sk_rmem_alloc);
1480
1481 /* If we've reached or overflowed our receive buffer, announce
1482 * a 0 rwnd if rwnd would still be positive. Store the
1483 * the pottential pressure overflow so that the window can be restored
1484 * back to original value.
1485 */
1486 if (rx_count >= asoc->base.sk->sk_rcvbuf)
1487 over = 1;
1488
Linus Torvalds1da177e2005-04-16 15:20:36 -07001489 if (asoc->rwnd >= len) {
1490 asoc->rwnd -= len;
Vlad Yasevich4d3c46e2009-09-04 18:20:59 -04001491 if (over) {
Vlad Yasevich65883372010-04-30 22:41:10 -04001492 asoc->rwnd_press += asoc->rwnd;
Vlad Yasevich4d3c46e2009-09-04 18:20:59 -04001493 asoc->rwnd = 0;
1494 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001495 } else {
1496 asoc->rwnd_over = len - asoc->rwnd;
1497 asoc->rwnd = 0;
1498 }
Vlad Yasevich4d3c46e2009-09-04 18:20:59 -04001499 SCTP_DEBUG_PRINTK("%s: asoc %p rwnd decreased by %d to (%u, %u, %u)\n",
Harvey Harrison0dc47872008-03-05 20:47:47 -08001500 __func__, asoc, len, asoc->rwnd,
Vlad Yasevich4d3c46e2009-09-04 18:20:59 -04001501 asoc->rwnd_over, asoc->rwnd_press);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001502}
1503
1504/* Build the bind address list for the association based on info from the
1505 * local endpoint and the remote peer.
1506 */
Alexey Dobriyan3182cd842005-07-11 20:57:47 -07001507int sctp_assoc_set_bind_addr_from_ep(struct sctp_association *asoc,
Vlad Yasevich409b95a2009-11-10 08:57:34 +00001508 sctp_scope_t scope, gfp_t gfp)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001509{
Linus Torvalds1da177e2005-04-16 15:20:36 -07001510 int flags;
1511
1512 /* Use scoping rules to determine the subset of addresses from
1513 * the endpoint.
1514 */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001515 flags = (PF_INET6 == asoc->base.sk->sk_family) ? SCTP_ADDR6_ALLOWED : 0;
1516 if (asoc->peer.ipv4_address)
1517 flags |= SCTP_ADDR4_PEERSUPP;
1518 if (asoc->peer.ipv6_address)
1519 flags |= SCTP_ADDR6_PEERSUPP;
1520
1521 return sctp_bind_addr_copy(&asoc->base.bind_addr,
1522 &asoc->ep->base.bind_addr,
1523 scope, gfp, flags);
1524}
1525
1526/* Build the association's bind address list from the cookie. */
1527int sctp_assoc_set_bind_addr_from_cookie(struct sctp_association *asoc,
Alexey Dobriyan3182cd842005-07-11 20:57:47 -07001528 struct sctp_cookie *cookie,
Al Virodd0fc662005-10-07 07:46:04 +01001529 gfp_t gfp)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001530{
1531 int var_size2 = ntohs(cookie->peer_init->chunk_hdr.length);
1532 int var_size3 = cookie->raw_addr_list_len;
1533 __u8 *raw = (__u8 *)cookie->peer_init + var_size2;
1534
1535 return sctp_raw_to_bind_addrs(&asoc->base.bind_addr, raw, var_size3,
1536 asoc->ep->base.bind_addr.port, gfp);
1537}
1538
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +09001539/* Lookup laddr in the bind address list of an association. */
1540int sctp_assoc_lookup_laddr(struct sctp_association *asoc,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001541 const union sctp_addr *laddr)
1542{
Vlad Yasevich559cf712007-09-16 16:03:28 -07001543 int found = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001544
Linus Torvalds1da177e2005-04-16 15:20:36 -07001545 if ((asoc->base.bind_addr.port == ntohs(laddr->v4.sin_port)) &&
1546 sctp_bind_addr_match(&asoc->base.bind_addr, laddr,
Vlad Yasevich559cf712007-09-16 16:03:28 -07001547 sctp_sk(asoc->base.sk)))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001548 found = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001549
Linus Torvalds1da177e2005-04-16 15:20:36 -07001550 return found;
1551}
Vlad Yasevich07d93962007-05-04 13:55:27 -07001552
1553/* Set an association id for a given association */
1554int sctp_assoc_set_id(struct sctp_association *asoc, gfp_t gfp)
1555{
1556 int assoc_id;
1557 int error = 0;
Vlad Yasevichc6ba68a2009-06-01 12:41:15 -04001558
1559 /* If the id is already assigned, keep it. */
1560 if (asoc->assoc_id)
1561 return error;
Vlad Yasevich07d93962007-05-04 13:55:27 -07001562retry:
1563 if (unlikely(!idr_pre_get(&sctp_assocs_id, gfp)))
1564 return -ENOMEM;
1565
1566 spin_lock_bh(&sctp_assocs_id_lock);
1567 error = idr_get_new_above(&sctp_assocs_id, (void *)asoc,
Vlad Yasevich48143262009-11-23 15:54:01 -05001568 idr_low, &assoc_id);
1569 if (!error) {
1570 idr_low = assoc_id + 1;
1571 if (idr_low == INT_MAX)
1572 idr_low = 1;
1573 }
Vlad Yasevich07d93962007-05-04 13:55:27 -07001574 spin_unlock_bh(&sctp_assocs_id_lock);
1575 if (error == -EAGAIN)
1576 goto retry;
1577 else if (error)
1578 return error;
1579
1580 asoc->assoc_id = (sctp_assoc_t) assoc_id;
1581 return error;
1582}
Vlad Yasevicha08de642007-12-20 14:11:47 -08001583
Wei Yongjun8b4472c2011-05-24 21:48:02 +00001584/* Free the ASCONF queue */
1585static void sctp_assoc_free_asconf_queue(struct sctp_association *asoc)
1586{
1587 struct sctp_chunk *asconf;
1588 struct sctp_chunk *tmp;
1589
1590 list_for_each_entry_safe(asconf, tmp, &asoc->addip_chunk_list, list) {
1591 list_del_init(&asconf->list);
1592 sctp_chunk_free(asconf);
1593 }
1594}
1595
Vlad Yasevicha08de642007-12-20 14:11:47 -08001596/* Free asconf_ack cache */
1597static void sctp_assoc_free_asconf_acks(struct sctp_association *asoc)
1598{
1599 struct sctp_chunk *ack;
1600 struct sctp_chunk *tmp;
1601
1602 list_for_each_entry_safe(ack, tmp, &asoc->asconf_ack_list,
1603 transmitted_list) {
1604 list_del_init(&ack->transmitted_list);
1605 sctp_chunk_free(ack);
1606 }
1607}
1608
1609/* Clean up the ASCONF_ACK queue */
1610void sctp_assoc_clean_asconf_ack_cache(const struct sctp_association *asoc)
1611{
1612 struct sctp_chunk *ack;
1613 struct sctp_chunk *tmp;
1614
Lucas De Marchi25985ed2011-03-30 22:57:33 -03001615 /* We can remove all the entries from the queue up to
Vlad Yasevicha08de642007-12-20 14:11:47 -08001616 * the "Peer-Sequence-Number".
1617 */
1618 list_for_each_entry_safe(ack, tmp, &asoc->asconf_ack_list,
1619 transmitted_list) {
1620 if (ack->subh.addip_hdr->serial ==
1621 htonl(asoc->peer.addip_serial))
1622 break;
1623
1624 list_del_init(&ack->transmitted_list);
1625 sctp_chunk_free(ack);
1626 }
1627}
1628
1629/* Find the ASCONF_ACK whose serial number matches ASCONF */
1630struct sctp_chunk *sctp_assoc_lookup_asconf_ack(
1631 const struct sctp_association *asoc,
1632 __be32 serial)
1633{
Wei Yongjuna8699812008-02-05 23:35:04 +09001634 struct sctp_chunk *ack;
Vlad Yasevicha08de642007-12-20 14:11:47 -08001635
1636 /* Walk through the list of cached ASCONF-ACKs and find the
1637 * ack chunk whose serial number matches that of the request.
1638 */
1639 list_for_each_entry(ack, &asoc->asconf_ack_list, transmitted_list) {
1640 if (ack->subh.addip_hdr->serial == serial) {
1641 sctp_chunk_hold(ack);
Wei Yongjuna8699812008-02-05 23:35:04 +09001642 return ack;
Vlad Yasevicha08de642007-12-20 14:11:47 -08001643 }
1644 }
1645
Wei Yongjuna8699812008-02-05 23:35:04 +09001646 return NULL;
Vlad Yasevicha08de642007-12-20 14:11:47 -08001647}
Wei Yongjuna000c012011-05-29 23:23:36 +00001648
1649void sctp_asconf_queue_teardown(struct sctp_association *asoc)
1650{
1651 /* Free any cached ASCONF_ACK chunk. */
1652 sctp_assoc_free_asconf_acks(asoc);
1653
1654 /* Free the ASCONF queue. */
1655 sctp_assoc_free_asconf_queue(asoc);
1656
1657 /* Free any cached ASCONF chunk. */
1658 if (asoc->addip_last_asconf)
1659 sctp_chunk_free(asoc->addip_last_asconf);
1660}