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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);
Linus Torvalds1da177e2005-04-16 15:20:36 -070067
Vlad Yasevich48143262009-11-23 15:54:01 -050068/* Keep track of the new idr low so that we don't re-use association id
69 * numbers too fast. It is protected by they idr spin lock is in the
70 * range of 1 - INT_MAX.
71 */
72static u32 idr_low = 1;
73
Linus Torvalds1da177e2005-04-16 15:20:36 -070074
75/* 1st Level Abstractions. */
76
77/* Initialize a new association from provided memory. */
78static struct sctp_association *sctp_association_init(struct sctp_association *asoc,
79 const struct sctp_endpoint *ep,
80 const struct sock *sk,
81 sctp_scope_t scope,
Al Virodd0fc662005-10-07 07:46:04 +010082 gfp_t gfp)
Linus Torvalds1da177e2005-04-16 15:20:36 -070083{
84 struct sctp_sock *sp;
85 int i;
Vlad Yasevicha29a5bd2007-09-16 19:31:35 -070086 sctp_paramhdr_t *p;
87 int err;
Linus Torvalds1da177e2005-04-16 15:20:36 -070088
89 /* Retrieve the SCTP per socket area. */
90 sp = sctp_sk((struct sock *)sk);
91
Linus Torvalds1da177e2005-04-16 15:20:36 -070092 /* Discarding const is appropriate here. */
93 asoc->ep = (struct sctp_endpoint *)ep;
94 sctp_endpoint_hold(asoc->ep);
95
96 /* Hold the sock. */
97 asoc->base.sk = (struct sock *)sk;
98 sock_hold(asoc->base.sk);
99
100 /* Initialize the common base substructure. */
101 asoc->base.type = SCTP_EP_TYPE_ASSOCIATION;
102
103 /* Initialize the object handling fields. */
104 atomic_set(&asoc->base.refcnt, 1);
105 asoc->base.dead = 0;
106 asoc->base.malloced = 0;
107
108 /* Initialize the bind addr area. */
109 sctp_bind_addr_init(&asoc->base.bind_addr, ep->base.bind_addr.port);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700110
111 asoc->state = SCTP_STATE_CLOSED;
112
113 /* Set these values from the socket values, a conversion between
114 * millsecons to seconds/microseconds must also be done.
115 */
116 asoc->cookie_life.tv_sec = sp->assocparams.sasoc_cookie_life / 1000;
117 asoc->cookie_life.tv_usec = (sp->assocparams.sasoc_cookie_life % 1000)
118 * 1000;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700119 asoc->frag_point = 0;
Vlad Yasevichf68b2e02009-09-04 18:21:00 -0400120 asoc->user_frag = sp->user_frag;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700121
122 /* Set the association max_retrans and RTO values from the
123 * socket values.
124 */
125 asoc->max_retrans = sp->assocparams.sasoc_asocmaxrxt;
126 asoc->rto_initial = msecs_to_jiffies(sp->rtoinfo.srto_initial);
127 asoc->rto_max = msecs_to_jiffies(sp->rtoinfo.srto_max);
128 asoc->rto_min = msecs_to_jiffies(sp->rtoinfo.srto_min);
129
130 asoc->overall_error_count = 0;
131
Frank Filz52ccb8e2005-12-22 11:36:46 -0800132 /* Initialize the association's heartbeat interval based on the
133 * sock configured value.
134 */
135 asoc->hbinterval = msecs_to_jiffies(sp->hbinterval);
136
137 /* Initialize path max retrans value. */
138 asoc->pathmaxrxt = sp->pathmaxrxt;
139
140 /* Initialize default path MTU. */
141 asoc->pathmtu = sp->pathmtu;
142
143 /* Set association default SACK delay */
144 asoc->sackdelay = msecs_to_jiffies(sp->sackdelay);
Wei Yongjund364d922008-05-09 15:13:26 -0700145 asoc->sackfreq = sp->sackfreq;
Frank Filz52ccb8e2005-12-22 11:36:46 -0800146
147 /* Set the association default flags controlling
148 * Heartbeat, SACK delay, and Path MTU Discovery.
149 */
150 asoc->param_flags = sp->param_flags;
151
Linus Torvalds1da177e2005-04-16 15:20:36 -0700152 /* Initialize the maximum mumber of new data packets that can be sent
153 * in a burst.
154 */
Vlad Yasevich70331572007-03-23 11:34:36 -0700155 asoc->max_burst = sp->max_burst;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700156
Vladislav Yasevich1e7d3d92005-11-11 16:06:16 -0800157 /* initialize association timers */
158 asoc->timeouts[SCTP_EVENT_TIMEOUT_NONE] = 0;
159 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_COOKIE] = asoc->rto_initial;
160 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_INIT] = asoc->rto_initial;
161 asoc->timeouts[SCTP_EVENT_TIMEOUT_T2_SHUTDOWN] = asoc->rto_initial;
162 asoc->timeouts[SCTP_EVENT_TIMEOUT_T3_RTX] = 0;
163 asoc->timeouts[SCTP_EVENT_TIMEOUT_T4_RTO] = 0;
164
165 /* sctpimpguide Section 2.12.2
166 * If the 'T5-shutdown-guard' timer is used, it SHOULD be set to the
167 * recommended value of 5 times 'RTO.Max'.
168 */
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +0900169 asoc->timeouts[SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD]
Vladislav Yasevich1e7d3d92005-11-11 16:06:16 -0800170 = 5 * asoc->rto_max;
171
172 asoc->timeouts[SCTP_EVENT_TIMEOUT_HEARTBEAT] = 0;
Frank Filz52ccb8e2005-12-22 11:36:46 -0800173 asoc->timeouts[SCTP_EVENT_TIMEOUT_SACK] = asoc->sackdelay;
Vladislav Yasevich1e7d3d92005-11-11 16:06:16 -0800174 asoc->timeouts[SCTP_EVENT_TIMEOUT_AUTOCLOSE] =
Andrei Pelinescu-Onciulda85b732009-11-23 15:54:01 -0500175 (unsigned long)sp->autoclose * HZ;
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +0900176
Uwe Kleine-König421f91d2010-06-11 12:17:00 +0200177 /* Initializes the timers */
Pavel Emelyanovb24b8a22008-01-23 21:20:07 -0800178 for (i = SCTP_EVENT_TIMEOUT_NONE; i < SCTP_NUM_TIMEOUT_TYPES; ++i)
179 setup_timer(&asoc->timers[i], sctp_timer_events[i],
180 (unsigned long)asoc);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700181
182 /* Pull default initialization values from the sock options.
183 * Note: This assumes that the values have already been
184 * validated in the sock.
185 */
186 asoc->c.sinit_max_instreams = sp->initmsg.sinit_max_instreams;
187 asoc->c.sinit_num_ostreams = sp->initmsg.sinit_num_ostreams;
188 asoc->max_init_attempts = sp->initmsg.sinit_max_attempts;
189
190 asoc->max_init_timeo =
191 msecs_to_jiffies(sp->initmsg.sinit_max_init_timeo);
192
193 /* Allocate storage for the ssnmap after the inbound and outbound
194 * streams have been negotiated during Init.
195 */
196 asoc->ssnmap = NULL;
197
198 /* Set the local window size for receive.
199 * This is also the rcvbuf space per association.
200 * RFC 6 - A SCTP receiver MUST be able to receive a minimum of
201 * 1500 bytes in one SCTP packet.
202 */
Neil Horman049b3ff2005-11-11 16:08:24 -0800203 if ((sk->sk_rcvbuf/2) < SCTP_DEFAULT_MINWINDOW)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700204 asoc->rwnd = SCTP_DEFAULT_MINWINDOW;
205 else
Neil Horman049b3ff2005-11-11 16:08:24 -0800206 asoc->rwnd = sk->sk_rcvbuf/2;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700207
208 asoc->a_rwnd = asoc->rwnd;
209
210 asoc->rwnd_over = 0;
Vlad Yasevich4d3c46e2009-09-04 18:20:59 -0400211 asoc->rwnd_press = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700212
213 /* Use my own max window until I learn something better. */
214 asoc->peer.rwnd = SCTP_DEFAULT_MAXWINDOW;
215
216 /* Set the sndbuf size for transmit. */
217 asoc->sndbuf_used = 0;
218
Neil Horman049b3ff2005-11-11 16:08:24 -0800219 /* Initialize the receive memory counter */
220 atomic_set(&asoc->rmem_alloc, 0);
221
Linus Torvalds1da177e2005-04-16 15:20:36 -0700222 init_waitqueue_head(&asoc->wait);
223
224 asoc->c.my_vtag = sctp_generate_tag(ep);
225 asoc->peer.i.init_tag = 0; /* INIT needs a vtag of 0. */
226 asoc->c.peer_vtag = 0;
227 asoc->c.my_ttag = 0;
228 asoc->c.peer_ttag = 0;
229 asoc->c.my_port = ep->base.bind_addr.port;
230
231 asoc->c.initial_tsn = sctp_generate_tsn(ep);
232
233 asoc->next_tsn = asoc->c.initial_tsn;
234
235 asoc->ctsn_ack_point = asoc->next_tsn - 1;
236 asoc->adv_peer_ack_point = asoc->ctsn_ack_point;
237 asoc->highest_sacked = asoc->ctsn_ack_point;
238 asoc->last_cwr_tsn = asoc->ctsn_ack_point;
239 asoc->unack_data = 0;
240
Linus Torvalds1da177e2005-04-16 15:20:36 -0700241 /* ADDIP Section 4.1 Asconf Chunk Procedures
242 *
243 * When an endpoint has an ASCONF signaled change to be sent to the
244 * remote endpoint it should do the following:
245 * ...
246 * A2) a serial number should be assigned to the chunk. The serial
247 * number SHOULD be a monotonically increasing number. The serial
248 * numbers SHOULD be initialized at the start of the
249 * association to the same value as the initial TSN.
250 */
251 asoc->addip_serial = asoc->c.initial_tsn;
252
David S. Miller79af02c2005-07-08 21:47:49 -0700253 INIT_LIST_HEAD(&asoc->addip_chunk_list);
Vlad Yasevicha08de642007-12-20 14:11:47 -0800254 INIT_LIST_HEAD(&asoc->asconf_ack_list);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700255
256 /* Make an empty list of remote transport addresses. */
257 INIT_LIST_HEAD(&asoc->peer.transport_addr_list);
Frank Filz3f7a87d2005-06-20 13:14:57 -0700258 asoc->peer.transport_count = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700259
260 /* RFC 2960 5.1 Normal Establishment of an Association
261 *
262 * After the reception of the first data chunk in an
263 * association the endpoint must immediately respond with a
264 * sack to acknowledge the data chunk. Subsequent
265 * acknowledgements should be done as described in Section
266 * 6.2.
267 *
268 * [We implement this by telling a new association that it
269 * already received one packet.]
270 */
271 asoc->peer.sack_needed = 1;
Wei Yongjund364d922008-05-09 15:13:26 -0700272 asoc->peer.sack_cnt = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700273
Vlad Yasevich73d9c4f2007-10-24 17:24:26 -0400274 /* Assume that the peer will tell us if he recognizes ASCONF
275 * as part of INIT exchange.
276 * The sctp_addip_noauth option is there for backward compatibilty
277 * and will revert old behavior.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700278 */
Vlad Yasevich88799fe2007-10-24 17:24:23 -0400279 asoc->peer.asconf_capable = 0;
Vlad Yasevich73d9c4f2007-10-24 17:24:26 -0400280 if (sctp_addip_noauth)
281 asoc->peer.asconf_capable = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700282
283 /* Create an input queue. */
284 sctp_inq_init(&asoc->base.inqueue);
David Howellsc4028952006-11-22 14:57:56 +0000285 sctp_inq_set_th_handler(&asoc->base.inqueue, sctp_assoc_bh_rcv);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700286
287 /* Create an output queue. */
288 sctp_outq_init(asoc, &asoc->outqueue);
289
290 if (!sctp_ulpq_init(&asoc->ulpq, asoc))
291 goto fail_init;
292
Vlad Yasevich8e1ee182008-10-08 14:18:39 -0700293 memset(&asoc->peer.tsn_map, 0, sizeof(struct sctp_tsnmap));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700294
295 asoc->need_ecne = 0;
296
297 asoc->assoc_id = 0;
298
299 /* Assume that peer would support both address types unless we are
300 * told otherwise.
301 */
302 asoc->peer.ipv4_address = 1;
Wei Yongjuna2c39582009-04-07 16:35:11 +0800303 if (asoc->base.sk->sk_family == PF_INET6)
304 asoc->peer.ipv6_address = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700305 INIT_LIST_HEAD(&asoc->asocs);
306
307 asoc->autoclose = sp->autoclose;
308
309 asoc->default_stream = sp->default_stream;
310 asoc->default_ppid = sp->default_ppid;
311 asoc->default_flags = sp->default_flags;
312 asoc->default_context = sp->default_context;
313 asoc->default_timetolive = sp->default_timetolive;
Ivan Skytte Jorgensen6ab792f2006-12-13 16:34:22 -0800314 asoc->default_rcv_context = sp->default_rcv_context;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700315
Vlad Yasevicha29a5bd2007-09-16 19:31:35 -0700316 /* AUTH related initializations */
317 INIT_LIST_HEAD(&asoc->endpoint_shared_keys);
318 err = sctp_auth_asoc_copy_shkeys(ep, asoc, gfp);
319 if (err)
320 goto fail_init;
321
322 asoc->active_key_id = ep->active_key_id;
323 asoc->asoc_shared_key = NULL;
324
325 asoc->default_hmac_id = 0;
326 /* Save the hmacs and chunks list into this association */
327 if (ep->auth_hmacs_list)
328 memcpy(asoc->c.auth_hmacs, ep->auth_hmacs_list,
329 ntohs(ep->auth_hmacs_list->param_hdr.length));
330 if (ep->auth_chunk_list)
331 memcpy(asoc->c.auth_chunks, ep->auth_chunk_list,
332 ntohs(ep->auth_chunk_list->param_hdr.length));
333
334 /* Get the AUTH random number for this association */
335 p = (sctp_paramhdr_t *)asoc->c.auth_random;
336 p->type = SCTP_PARAM_RANDOM;
337 p->length = htons(sizeof(sctp_paramhdr_t) + SCTP_AUTH_RANDOM_LENGTH);
338 get_random_bytes(p+1, SCTP_AUTH_RANDOM_LENGTH);
339
Linus Torvalds1da177e2005-04-16 15:20:36 -0700340 return asoc;
341
342fail_init:
343 sctp_endpoint_put(asoc->ep);
344 sock_put(asoc->base.sk);
345 return NULL;
346}
347
348/* Allocate and initialize a new association */
349struct sctp_association *sctp_association_new(const struct sctp_endpoint *ep,
350 const struct sock *sk,
Alexey Dobriyan3182cd842005-07-11 20:57:47 -0700351 sctp_scope_t scope,
Al Virodd0fc662005-10-07 07:46:04 +0100352 gfp_t gfp)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700353{
354 struct sctp_association *asoc;
355
356 asoc = t_new(struct sctp_association, gfp);
357 if (!asoc)
358 goto fail;
359
360 if (!sctp_association_init(asoc, ep, sk, scope, gfp))
361 goto fail_init;
362
363 asoc->base.malloced = 1;
364 SCTP_DBG_OBJCNT_INC(assoc);
Frank Filz3f7a87d2005-06-20 13:14:57 -0700365 SCTP_DEBUG_PRINTK("Created asoc %p\n", asoc);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700366
367 return asoc;
368
369fail_init:
370 kfree(asoc);
371fail:
372 return NULL;
373}
374
375/* Free this association if possible. There may still be users, so
376 * the actual deallocation may be delayed.
377 */
378void sctp_association_free(struct sctp_association *asoc)
379{
380 struct sock *sk = asoc->base.sk;
381 struct sctp_transport *transport;
382 struct list_head *pos, *temp;
383 int i;
384
Vlad Yasevichde76e692006-10-30 18:55:11 -0800385 /* Only real associations count against the endpoint, so
386 * don't bother for if this is a temporary association.
387 */
388 if (!asoc->temp) {
389 list_del(&asoc->asocs);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700390
Vlad Yasevichde76e692006-10-30 18:55:11 -0800391 /* Decrement the backlog value for a TCP-style listening
392 * socket.
393 */
394 if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING))
395 sk->sk_ack_backlog--;
396 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700397
398 /* Mark as dead, so other users can know this structure is
399 * going away.
400 */
401 asoc->base.dead = 1;
402
403 /* Dispose of any data lying around in the outqueue. */
404 sctp_outq_free(&asoc->outqueue);
405
406 /* Dispose of any pending messages for the upper layer. */
407 sctp_ulpq_free(&asoc->ulpq);
408
409 /* Dispose of any pending chunks on the inqueue. */
410 sctp_inq_free(&asoc->base.inqueue);
411
Vlad Yasevich8e1ee182008-10-08 14:18:39 -0700412 sctp_tsnmap_free(&asoc->peer.tsn_map);
413
Linus Torvalds1da177e2005-04-16 15:20:36 -0700414 /* Free ssnmap storage. */
415 sctp_ssnmap_free(asoc->ssnmap);
416
417 /* Clean up the bound address list. */
418 sctp_bind_addr_free(&asoc->base.bind_addr);
419
420 /* Do we need to go through all of our timers and
421 * delete them? To be safe we will try to delete all, but we
422 * should be able to go through and make a guess based
423 * on our state.
424 */
425 for (i = SCTP_EVENT_TIMEOUT_NONE; i < SCTP_NUM_TIMEOUT_TYPES; ++i) {
426 if (timer_pending(&asoc->timers[i]) &&
427 del_timer(&asoc->timers[i]))
428 sctp_association_put(asoc);
429 }
430
431 /* Free peer's cached cookie. */
Jesper Juhla51482b2005-11-08 09:41:34 -0800432 kfree(asoc->peer.cookie);
Vlad Yasevich730fc3d2007-09-16 19:32:11 -0700433 kfree(asoc->peer.peer_random);
434 kfree(asoc->peer.peer_chunks);
435 kfree(asoc->peer.peer_hmacs);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700436
437 /* Release the transport structures. */
438 list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
439 transport = list_entry(pos, struct sctp_transport, transports);
440 list_del(pos);
441 sctp_transport_free(transport);
442 }
443
Frank Filz3f7a87d2005-06-20 13:14:57 -0700444 asoc->peer.transport_count = 0;
445
Linus Torvalds1da177e2005-04-16 15:20:36 -0700446 /* Free any cached ASCONF_ACK chunk. */
Vlad Yasevicha08de642007-12-20 14:11:47 -0800447 sctp_assoc_free_asconf_acks(asoc);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700448
449 /* Free any cached ASCONF chunk. */
450 if (asoc->addip_last_asconf)
451 sctp_chunk_free(asoc->addip_last_asconf);
452
Vlad Yasevicha29a5bd2007-09-16 19:31:35 -0700453 /* AUTH - Free the endpoint shared keys */
454 sctp_auth_destroy_keys(&asoc->endpoint_shared_keys);
455
456 /* AUTH - Free the association shared key */
457 sctp_auth_key_put(asoc->asoc_shared_key);
458
Linus Torvalds1da177e2005-04-16 15:20:36 -0700459 sctp_association_put(asoc);
460}
461
462/* Cleanup and free up an association. */
463static void sctp_association_destroy(struct sctp_association *asoc)
464{
465 SCTP_ASSERT(asoc->base.dead, "Assoc is not dead", return);
466
467 sctp_endpoint_put(asoc->ep);
468 sock_put(asoc->base.sk);
469
470 if (asoc->assoc_id != 0) {
471 spin_lock_bh(&sctp_assocs_id_lock);
472 idr_remove(&sctp_assocs_id, asoc->assoc_id);
473 spin_unlock_bh(&sctp_assocs_id_lock);
474 }
475
Ilpo Järvinen547b7922008-07-25 21:43:18 -0700476 WARN_ON(atomic_read(&asoc->rmem_alloc));
Neil Horman049b3ff2005-11-11 16:08:24 -0800477
Linus Torvalds1da177e2005-04-16 15:20:36 -0700478 if (asoc->base.malloced) {
479 kfree(asoc);
480 SCTP_DBG_OBJCNT_DEC(assoc);
481 }
482}
483
484/* Change the primary destination address for the peer. */
485void sctp_assoc_set_primary(struct sctp_association *asoc,
486 struct sctp_transport *transport)
487{
Vlad Yasevich319fa2a2008-06-16 17:00:29 -0700488 int changeover = 0;
489
490 /* it's a changeover only if we already have a primary path
491 * that we are changing
492 */
493 if (asoc->peer.primary_path != NULL &&
494 asoc->peer.primary_path != transport)
495 changeover = 1 ;
496
Linus Torvalds1da177e2005-04-16 15:20:36 -0700497 asoc->peer.primary_path = transport;
498
499 /* Set a default msg_name for events. */
500 memcpy(&asoc->peer.primary_addr, &transport->ipaddr,
501 sizeof(union sctp_addr));
502
503 /* If the primary path is changing, assume that the
504 * user wants to use this new path.
505 */
Sridhar Samudralaad8fec12006-07-21 14:48:50 -0700506 if ((transport->state == SCTP_ACTIVE) ||
507 (transport->state == SCTP_UNKNOWN))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700508 asoc->peer.active_path = transport;
509
510 /*
511 * SFR-CACC algorithm:
512 * Upon the receipt of a request to change the primary
513 * destination address, on the data structure for the new
514 * primary destination, the sender MUST do the following:
515 *
516 * 1) If CHANGEOVER_ACTIVE is set, then there was a switch
517 * to this destination address earlier. The sender MUST set
518 * CYCLING_CHANGEOVER to indicate that this switch is a
519 * double switch to the same destination address.
Vlad Yaseviche0e9db12009-11-23 15:53:57 -0500520 *
521 * Really, only bother is we have data queued or outstanding on
522 * the association.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700523 */
Vlad Yaseviche0e9db12009-11-23 15:53:57 -0500524 if (!asoc->outqueue.outstanding_bytes && !asoc->outqueue.out_qlen)
525 return;
526
Linus Torvalds1da177e2005-04-16 15:20:36 -0700527 if (transport->cacc.changeover_active)
Vlad Yasevich319fa2a2008-06-16 17:00:29 -0700528 transport->cacc.cycling_changeover = changeover;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700529
530 /* 2) The sender MUST set CHANGEOVER_ACTIVE to indicate that
531 * a changeover has occurred.
532 */
Vlad Yasevich319fa2a2008-06-16 17:00:29 -0700533 transport->cacc.changeover_active = changeover;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700534
535 /* 3) The sender MUST store the next TSN to be sent in
536 * next_tsn_at_change.
537 */
538 transport->cacc.next_tsn_at_change = asoc->next_tsn;
539}
540
Frank Filz3f7a87d2005-06-20 13:14:57 -0700541/* Remove a transport from an association. */
542void sctp_assoc_rm_peer(struct sctp_association *asoc,
543 struct sctp_transport *peer)
544{
545 struct list_head *pos;
546 struct sctp_transport *transport;
547
548 SCTP_DEBUG_PRINTK_IPADDR("sctp_assoc_rm_peer:association %p addr: ",
549 " port: %d\n",
550 asoc,
551 (&peer->ipaddr),
Al Virob3f5b3b2006-11-20 17:22:43 -0800552 ntohs(peer->ipaddr.v4.sin_port));
Frank Filz3f7a87d2005-06-20 13:14:57 -0700553
554 /* If we are to remove the current retran_path, update it
555 * to the next peer before removing this peer from the list.
556 */
557 if (asoc->peer.retran_path == peer)
558 sctp_assoc_update_retran_path(asoc);
559
560 /* Remove this peer from the list. */
561 list_del(&peer->transports);
562
563 /* Get the first transport of asoc. */
564 pos = asoc->peer.transport_addr_list.next;
565 transport = list_entry(pos, struct sctp_transport, transports);
566
567 /* Update any entries that match the peer to be deleted. */
568 if (asoc->peer.primary_path == peer)
569 sctp_assoc_set_primary(asoc, transport);
570 if (asoc->peer.active_path == peer)
571 asoc->peer.active_path = transport;
572 if (asoc->peer.last_data_from == peer)
573 asoc->peer.last_data_from = transport;
574
575 /* If we remove the transport an INIT was last sent to, set it to
576 * NULL. Combined with the update of the retran path above, this
577 * will cause the next INIT to be sent to the next available
578 * transport, maintaining the cycle.
579 */
580 if (asoc->init_last_sent_to == peer)
581 asoc->init_last_sent_to = NULL;
582
Wei Yongjun6345b192009-04-26 23:13:35 +0800583 /* If we remove the transport an SHUTDOWN was last sent to, set it
584 * to NULL. Combined with the update of the retran path above, this
585 * will cause the next SHUTDOWN to be sent to the next available
586 * transport, maintaining the cycle.
587 */
588 if (asoc->shutdown_last_sent_to == peer)
589 asoc->shutdown_last_sent_to = NULL;
590
Wei Yongjun10a43ce2009-04-26 23:14:42 +0800591 /* If we remove the transport an ASCONF was last sent to, set it to
592 * NULL.
593 */
594 if (asoc->addip_last_asconf &&
595 asoc->addip_last_asconf->transport == peer)
596 asoc->addip_last_asconf->transport = NULL;
597
Vlad Yasevich31b02e12009-09-04 18:21:00 -0400598 /* If we have something on the transmitted list, we have to
599 * save it off. The best place is the active path.
600 */
601 if (!list_empty(&peer->transmitted)) {
602 struct sctp_transport *active = asoc->peer.active_path;
603 struct sctp_chunk *ch;
604
605 /* Reset the transport of each chunk on this list */
606 list_for_each_entry(ch, &peer->transmitted,
607 transmitted_list) {
608 ch->transport = NULL;
609 ch->rtt_in_progress = 0;
610 }
611
612 list_splice_tail_init(&peer->transmitted,
613 &active->transmitted);
614
615 /* Start a T3 timer here in case it wasn't running so
616 * that these migrated packets have a chance to get
617 * retrnasmitted.
618 */
619 if (!timer_pending(&active->T3_rtx_timer))
620 if (!mod_timer(&active->T3_rtx_timer,
621 jiffies + active->rto))
622 sctp_transport_hold(active);
623 }
624
Frank Filz3f7a87d2005-06-20 13:14:57 -0700625 asoc->peer.transport_count--;
626
627 sctp_transport_free(peer);
628}
629
Linus Torvalds1da177e2005-04-16 15:20:36 -0700630/* Add a transport address to an association. */
631struct sctp_transport *sctp_assoc_add_peer(struct sctp_association *asoc,
632 const union sctp_addr *addr,
Al Virodd0fc662005-10-07 07:46:04 +0100633 const gfp_t gfp,
Frank Filz3f7a87d2005-06-20 13:14:57 -0700634 const int peer_state)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700635{
636 struct sctp_transport *peer;
637 struct sctp_sock *sp;
638 unsigned short port;
639
640 sp = sctp_sk(asoc->base.sk);
641
642 /* AF_INET and AF_INET6 share common port field. */
Al Viro4bdf4b52006-11-20 17:10:20 -0800643 port = ntohs(addr->v4.sin_port);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700644
Frank Filz3f7a87d2005-06-20 13:14:57 -0700645 SCTP_DEBUG_PRINTK_IPADDR("sctp_assoc_add_peer:association %p addr: ",
Sridhar Samudralaad8fec12006-07-21 14:48:50 -0700646 " port: %d state:%d\n",
Frank Filz3f7a87d2005-06-20 13:14:57 -0700647 asoc,
648 addr,
Al Viro4bdf4b52006-11-20 17:10:20 -0800649 port,
Sridhar Samudralaad8fec12006-07-21 14:48:50 -0700650 peer_state);
Frank Filz3f7a87d2005-06-20 13:14:57 -0700651
Linus Torvalds1da177e2005-04-16 15:20:36 -0700652 /* Set the port if it has not been set yet. */
653 if (0 == asoc->peer.port)
654 asoc->peer.port = port;
655
656 /* Check to see if this is a duplicate. */
657 peer = sctp_assoc_lookup_paddr(asoc, addr);
Frank Filz3f7a87d2005-06-20 13:14:57 -0700658 if (peer) {
Vlad Yasevichadd52372008-09-18 16:28:27 -0700659 /* An UNKNOWN state is only set on transports added by
660 * user in sctp_connectx() call. Such transports should be
661 * considered CONFIRMED per RFC 4960, Section 5.4.
662 */
Sridhar Samudralaad8fec12006-07-21 14:48:50 -0700663 if (peer->state == SCTP_UNKNOWN) {
Vlad Yasevichadd52372008-09-18 16:28:27 -0700664 peer->state = SCTP_ACTIVE;
Sridhar Samudralaad8fec12006-07-21 14:48:50 -0700665 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700666 return peer;
Frank Filz3f7a87d2005-06-20 13:14:57 -0700667 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700668
669 peer = sctp_transport_new(addr, gfp);
670 if (!peer)
671 return NULL;
672
673 sctp_transport_set_owner(peer, asoc);
674
Frank Filz52ccb8e2005-12-22 11:36:46 -0800675 /* Initialize the peer's heartbeat interval based on the
676 * association configured value.
677 */
678 peer->hbinterval = asoc->hbinterval;
679
680 /* Set the path max_retrans. */
681 peer->pathmaxrxt = asoc->pathmaxrxt;
682
683 /* Initialize the peer's SACK delay timeout based on the
684 * association configured value.
685 */
686 peer->sackdelay = asoc->sackdelay;
Wei Yongjund364d922008-05-09 15:13:26 -0700687 peer->sackfreq = asoc->sackfreq;
Frank Filz52ccb8e2005-12-22 11:36:46 -0800688
689 /* Enable/disable heartbeat, SACK delay, and path MTU discovery
690 * based on association setting.
691 */
692 peer->param_flags = asoc->param_flags;
693
Vlad Yasevich8da645e2009-09-04 18:21:01 -0400694 sctp_transport_route(peer, NULL, sp);
695
Linus Torvalds1da177e2005-04-16 15:20:36 -0700696 /* Initialize the pmtu of the transport. */
Vlad Yasevich8da645e2009-09-04 18:21:01 -0400697 if (peer->param_flags & SPP_PMTUD_DISABLE) {
698 if (asoc->pathmtu)
699 peer->pathmtu = asoc->pathmtu;
700 else
701 peer->pathmtu = SCTP_DEFAULT_MAXSEGMENT;
702 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700703
704 /* If this is the first transport addr on this association,
705 * initialize the association PMTU to the peer's PMTU.
706 * If not and the current association PMTU is higher than the new
707 * peer's PMTU, reset the association PMTU to the new peer's PMTU.
708 */
Frank Filz52ccb8e2005-12-22 11:36:46 -0800709 if (asoc->pathmtu)
710 asoc->pathmtu = min_t(int, peer->pathmtu, asoc->pathmtu);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700711 else
Frank Filz52ccb8e2005-12-22 11:36:46 -0800712 asoc->pathmtu = peer->pathmtu;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700713
714 SCTP_DEBUG_PRINTK("sctp_assoc_add_peer:association %p PMTU set to "
Frank Filz52ccb8e2005-12-22 11:36:46 -0800715 "%d\n", asoc, asoc->pathmtu);
Florian Westphal6d0ccba2008-07-18 23:04:39 -0700716 peer->pmtu_pending = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700717
Vlad Yasevichf68b2e02009-09-04 18:21:00 -0400718 asoc->frag_point = sctp_frag_point(asoc, asoc->pathmtu);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700719
720 /* The asoc->peer.port might not be meaningful yet, but
721 * initialize the packet structure anyway.
722 */
723 sctp_packet_init(&peer->packet, peer, asoc->base.bind_addr.port,
724 asoc->peer.port);
725
726 /* 7.2.1 Slow-Start
727 *
728 * o The initial cwnd before DATA transmission or after a sufficiently
729 * long idle period MUST be set to
730 * min(4*MTU, max(2*MTU, 4380 bytes))
731 *
732 * o The initial value of ssthresh MAY be arbitrarily high
733 * (for example, implementations MAY use the size of the
734 * receiver advertised window).
735 */
Frank Filz52ccb8e2005-12-22 11:36:46 -0800736 peer->cwnd = min(4*asoc->pathmtu, max_t(__u32, 2*asoc->pathmtu, 4380));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700737
738 /* At this point, we may not have the receiver's advertised window,
739 * so initialize ssthresh to the default value and it will be set
740 * later when we process the INIT.
741 */
742 peer->ssthresh = SCTP_DEFAULT_MAXWINDOW;
743
744 peer->partial_bytes_acked = 0;
745 peer->flight_size = 0;
Vlad Yasevich46d5a802009-11-23 15:54:00 -0500746 peer->burst_limited = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700747
Linus Torvalds1da177e2005-04-16 15:20:36 -0700748 /* Set the transport's RTO.initial value */
749 peer->rto = asoc->rto_initial;
750
Frank Filz3f7a87d2005-06-20 13:14:57 -0700751 /* Set the peer's active state. */
752 peer->state = peer_state;
753
Linus Torvalds1da177e2005-04-16 15:20:36 -0700754 /* Attach the remote transport to our asoc. */
755 list_add_tail(&peer->transports, &asoc->peer.transport_addr_list);
Frank Filz3f7a87d2005-06-20 13:14:57 -0700756 asoc->peer.transport_count++;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700757
758 /* If we do not yet have a primary path, set one. */
759 if (!asoc->peer.primary_path) {
760 sctp_assoc_set_primary(asoc, peer);
761 asoc->peer.retran_path = peer;
762 }
763
Vlad Yasevichfbdf5012010-04-30 22:39:26 -0400764 if (asoc->peer.active_path == asoc->peer.retran_path &&
765 peer->state != SCTP_UNCONFIRMED) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700766 asoc->peer.retran_path = peer;
Frank Filz3f7a87d2005-06-20 13:14:57 -0700767 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700768
769 return peer;
770}
771
772/* Delete a transport address from an association. */
773void sctp_assoc_del_peer(struct sctp_association *asoc,
774 const union sctp_addr *addr)
775{
776 struct list_head *pos;
777 struct list_head *temp;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700778 struct sctp_transport *transport;
779
780 list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
781 transport = list_entry(pos, struct sctp_transport, transports);
782 if (sctp_cmp_addr_exact(addr, &transport->ipaddr)) {
Frank Filz3f7a87d2005-06-20 13:14:57 -0700783 /* Do book keeping for removing the peer and free it. */
784 sctp_assoc_rm_peer(asoc, transport);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700785 break;
786 }
787 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700788}
789
790/* Lookup a transport by address. */
791struct sctp_transport *sctp_assoc_lookup_paddr(
792 const struct sctp_association *asoc,
793 const union sctp_addr *address)
794{
795 struct sctp_transport *t;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700796
797 /* Cycle through all transports searching for a peer address. */
798
Robert P. J. Day9dbc15f2008-04-12 18:54:24 -0700799 list_for_each_entry(t, &asoc->peer.transport_addr_list,
800 transports) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700801 if (sctp_cmp_addr_exact(address, &t->ipaddr))
802 return t;
803 }
804
805 return NULL;
806}
807
Vlad Yasevich42e30bf2007-12-20 14:08:56 -0800808/* Remove all transports except a give one */
809void sctp_assoc_del_nonprimary_peers(struct sctp_association *asoc,
810 struct sctp_transport *primary)
811{
812 struct sctp_transport *temp;
813 struct sctp_transport *t;
814
815 list_for_each_entry_safe(t, temp, &asoc->peer.transport_addr_list,
816 transports) {
817 /* if the current transport is not the primary one, delete it */
818 if (t != primary)
819 sctp_assoc_rm_peer(asoc, t);
820 }
Vlad Yasevich42e30bf2007-12-20 14:08:56 -0800821}
822
Linus Torvalds1da177e2005-04-16 15:20:36 -0700823/* Engage in transport control operations.
824 * Mark the transport up or down and send a notification to the user.
825 * Select and update the new active and retran paths.
826 */
827void sctp_assoc_control_transport(struct sctp_association *asoc,
828 struct sctp_transport *transport,
829 sctp_transport_cmd_t command,
830 sctp_sn_error_t error)
831{
832 struct sctp_transport *t = NULL;
833 struct sctp_transport *first;
834 struct sctp_transport *second;
835 struct sctp_ulpevent *event;
Al Viro0906e202006-11-20 17:03:01 -0800836 struct sockaddr_storage addr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700837 int spc_state = 0;
838
839 /* Record the transition on the transport. */
840 switch (command) {
841 case SCTP_TRANSPORT_UP:
Vlad Yasevich1ae41142007-03-23 11:32:26 -0700842 /* If we are moving from UNCONFIRMED state due
843 * to heartbeat success, report the SCTP_ADDR_CONFIRMED
844 * state to the user, otherwise report SCTP_ADDR_AVAILABLE.
845 */
846 if (SCTP_UNCONFIRMED == transport->state &&
847 SCTP_HEARTBEAT_SUCCESS == error)
848 spc_state = SCTP_ADDR_CONFIRMED;
849 else
850 spc_state = SCTP_ADDR_AVAILABLE;
Frank Filz3f7a87d2005-06-20 13:14:57 -0700851 transport->state = SCTP_ACTIVE;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700852 break;
853
854 case SCTP_TRANSPORT_DOWN:
Vlad Yasevich40187882009-06-23 11:28:05 -0400855 /* If the transport was never confirmed, do not transition it
856 * to inactive state. Also, release the cached route since
857 * there may be a better route next time.
Vlad Yasevichcc756892007-08-24 19:30:25 +0900858 */
859 if (transport->state != SCTP_UNCONFIRMED)
860 transport->state = SCTP_INACTIVE;
Vlad Yasevich40187882009-06-23 11:28:05 -0400861 else {
862 dst_release(transport->dst);
863 transport->dst = NULL;
864 }
Vlad Yasevichcc756892007-08-24 19:30:25 +0900865
Linus Torvalds1da177e2005-04-16 15:20:36 -0700866 spc_state = SCTP_ADDR_UNREACHABLE;
867 break;
868
869 default:
870 return;
Stephen Hemminger3ff50b72007-04-20 17:09:22 -0700871 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700872
873 /* Generate and send a SCTP_PEER_ADDR_CHANGE notification to the
874 * user.
875 */
Al Viro0906e202006-11-20 17:03:01 -0800876 memset(&addr, 0, sizeof(struct sockaddr_storage));
Al Viro8cec6b82006-11-20 17:23:01 -0800877 memcpy(&addr, &transport->ipaddr, transport->af_specific->sockaddr_len);
Al Viro0906e202006-11-20 17:03:01 -0800878 event = sctp_ulpevent_make_peer_addr_change(asoc, &addr,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700879 0, spc_state, error, GFP_ATOMIC);
880 if (event)
881 sctp_ulpq_tail_event(&asoc->ulpq, event);
882
883 /* Select new active and retran paths. */
884
885 /* Look for the two most recently used active transports.
886 *
887 * This code produces the wrong ordering whenever jiffies
888 * rolls over, but we still get usable transports, so we don't
889 * worry about it.
890 */
891 first = NULL; second = NULL;
892
Robert P. J. Day9dbc15f2008-04-12 18:54:24 -0700893 list_for_each_entry(t, &asoc->peer.transport_addr_list,
894 transports) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700895
Sridhar Samudralaad8fec12006-07-21 14:48:50 -0700896 if ((t->state == SCTP_INACTIVE) ||
897 (t->state == SCTP_UNCONFIRMED))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700898 continue;
899 if (!first || t->last_time_heard > first->last_time_heard) {
900 second = first;
901 first = t;
902 }
903 if (!second || t->last_time_heard > second->last_time_heard)
904 second = t;
905 }
906
907 /* RFC 2960 6.4 Multi-Homed SCTP Endpoints
908 *
909 * By default, an endpoint should always transmit to the
910 * primary path, unless the SCTP user explicitly specifies the
911 * destination transport address (and possibly source
912 * transport address) to use.
913 *
914 * [If the primary is active but not most recent, bump the most
915 * recently used transport.]
916 */
Sridhar Samudralaad8fec12006-07-21 14:48:50 -0700917 if (((asoc->peer.primary_path->state == SCTP_ACTIVE) ||
918 (asoc->peer.primary_path->state == SCTP_UNKNOWN)) &&
Linus Torvalds1da177e2005-04-16 15:20:36 -0700919 first != asoc->peer.primary_path) {
920 second = first;
921 first = asoc->peer.primary_path;
922 }
923
924 /* If we failed to find a usable transport, just camp on the
925 * primary, even if it is inactive.
926 */
927 if (!first) {
928 first = asoc->peer.primary_path;
929 second = asoc->peer.primary_path;
930 }
931
932 /* Set the active and retran transports. */
933 asoc->peer.active_path = first;
934 asoc->peer.retran_path = second;
935}
936
937/* Hold a reference to an association. */
938void sctp_association_hold(struct sctp_association *asoc)
939{
940 atomic_inc(&asoc->base.refcnt);
941}
942
943/* Release a reference to an association and cleanup
944 * if there are no more references.
945 */
946void sctp_association_put(struct sctp_association *asoc)
947{
948 if (atomic_dec_and_test(&asoc->base.refcnt))
949 sctp_association_destroy(asoc);
950}
951
952/* Allocate the next TSN, Transmission Sequence Number, for the given
953 * association.
954 */
955__u32 sctp_association_get_next_tsn(struct sctp_association *asoc)
956{
957 /* From Section 1.6 Serial Number Arithmetic:
958 * Transmission Sequence Numbers wrap around when they reach
959 * 2**32 - 1. That is, the next TSN a DATA chunk MUST use
960 * after transmitting TSN = 2*32 - 1 is TSN = 0.
961 */
962 __u32 retval = asoc->next_tsn;
963 asoc->next_tsn++;
964 asoc->unack_data++;
965
966 return retval;
967}
968
969/* Compare two addresses to see if they match. Wildcard addresses
970 * only match themselves.
971 */
972int sctp_cmp_addr_exact(const union sctp_addr *ss1,
973 const union sctp_addr *ss2)
974{
975 struct sctp_af *af;
976
977 af = sctp_get_af_specific(ss1->sa.sa_family);
978 if (unlikely(!af))
979 return 0;
980
981 return af->cmp_addr(ss1, ss2);
982}
983
984/* Return an ecne chunk to get prepended to a packet.
985 * Note: We are sly and return a shared, prealloced chunk. FIXME:
986 * No we don't, but we could/should.
987 */
988struct sctp_chunk *sctp_get_ecne_prepend(struct sctp_association *asoc)
989{
990 struct sctp_chunk *chunk;
991
992 /* Send ECNE if needed.
993 * Not being able to allocate a chunk here is not deadly.
994 */
995 if (asoc->need_ecne)
996 chunk = sctp_make_ecne(asoc, asoc->last_ecne_tsn);
997 else
998 chunk = NULL;
999
1000 return chunk;
1001}
1002
1003/*
1004 * Find which transport this TSN was sent on.
1005 */
1006struct sctp_transport *sctp_assoc_lookup_tsn(struct sctp_association *asoc,
1007 __u32 tsn)
1008{
1009 struct sctp_transport *active;
1010 struct sctp_transport *match;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001011 struct sctp_transport *transport;
1012 struct sctp_chunk *chunk;
Al Virodbc16db2006-11-20 17:01:42 -08001013 __be32 key = htonl(tsn);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001014
1015 match = NULL;
1016
1017 /*
1018 * FIXME: In general, find a more efficient data structure for
1019 * searching.
1020 */
1021
1022 /*
1023 * The general strategy is to search each transport's transmitted
1024 * list. Return which transport this TSN lives on.
1025 *
1026 * Let's be hopeful and check the active_path first.
1027 * Another optimization would be to know if there is only one
1028 * outbound path and not have to look for the TSN at all.
1029 *
1030 */
1031
1032 active = asoc->peer.active_path;
1033
Robert P. J. Day9dbc15f2008-04-12 18:54:24 -07001034 list_for_each_entry(chunk, &active->transmitted,
1035 transmitted_list) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001036
1037 if (key == chunk->subh.data_hdr->tsn) {
1038 match = active;
1039 goto out;
1040 }
1041 }
1042
1043 /* If not found, go search all the other transports. */
Robert P. J. Day9dbc15f2008-04-12 18:54:24 -07001044 list_for_each_entry(transport, &asoc->peer.transport_addr_list,
1045 transports) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001046
1047 if (transport == active)
1048 break;
Robert P. J. Day9dbc15f2008-04-12 18:54:24 -07001049 list_for_each_entry(chunk, &transport->transmitted,
1050 transmitted_list) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001051 if (key == chunk->subh.data_hdr->tsn) {
1052 match = transport;
1053 goto out;
1054 }
1055 }
1056 }
1057out:
1058 return match;
1059}
1060
1061/* Is this the association we are looking for? */
1062struct sctp_transport *sctp_assoc_is_match(struct sctp_association *asoc,
1063 const union sctp_addr *laddr,
1064 const union sctp_addr *paddr)
1065{
1066 struct sctp_transport *transport;
1067
Al Viroe2fcced2006-11-20 17:08:41 -08001068 if ((htons(asoc->base.bind_addr.port) == laddr->v4.sin_port) &&
1069 (htons(asoc->peer.port) == paddr->v4.sin_port)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001070 transport = sctp_assoc_lookup_paddr(asoc, paddr);
1071 if (!transport)
1072 goto out;
1073
1074 if (sctp_bind_addr_match(&asoc->base.bind_addr, laddr,
1075 sctp_sk(asoc->base.sk)))
1076 goto out;
1077 }
1078 transport = NULL;
1079
1080out:
Linus Torvalds1da177e2005-04-16 15:20:36 -07001081 return transport;
1082}
1083
1084/* Do delayed input processing. This is scheduled by sctp_rcv(). */
David Howellsc4028952006-11-22 14:57:56 +00001085static void sctp_assoc_bh_rcv(struct work_struct *work)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001086{
David Howellsc4028952006-11-22 14:57:56 +00001087 struct sctp_association *asoc =
1088 container_of(work, struct sctp_association,
1089 base.inqueue.immediate);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001090 struct sctp_endpoint *ep;
1091 struct sctp_chunk *chunk;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001092 struct sctp_inq *inqueue;
1093 int state;
1094 sctp_subtype_t subtype;
1095 int error = 0;
1096
1097 /* The association should be held so we should be safe. */
1098 ep = asoc->ep;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001099
1100 inqueue = &asoc->base.inqueue;
1101 sctp_association_hold(asoc);
1102 while (NULL != (chunk = sctp_inq_pop(inqueue))) {
1103 state = asoc->state;
1104 subtype = SCTP_ST_CHUNK(chunk->chunk_hdr->type);
1105
Vlad Yasevichbbd0d592007-10-03 17:51:34 -07001106 /* SCTP-AUTH, Section 6.3:
1107 * The receiver has a list of chunk types which it expects
1108 * to be received only after an AUTH-chunk. This list has
1109 * been sent to the peer during the association setup. It
1110 * MUST silently discard these chunks if they are not placed
1111 * after an AUTH chunk in the packet.
1112 */
1113 if (sctp_auth_recv_cid(subtype.chunk, asoc) && !chunk->auth)
1114 continue;
1115
Linus Torvalds1da177e2005-04-16 15:20:36 -07001116 /* Remember where the last DATA chunk came from so we
1117 * know where to send the SACK.
1118 */
1119 if (sctp_chunk_is_data(chunk))
1120 asoc->peer.last_data_from = chunk->transport;
1121 else
1122 SCTP_INC_STATS(SCTP_MIB_INCTRLCHUNKS);
1123
1124 if (chunk->transport)
1125 chunk->transport->last_time_heard = jiffies;
1126
1127 /* Run through the state machine. */
1128 error = sctp_do_sm(SCTP_EVENT_T_CHUNK, subtype,
1129 state, ep, asoc, chunk, GFP_ATOMIC);
1130
1131 /* Check to see if the association is freed in response to
1132 * the incoming chunk. If so, get out of the while loop.
1133 */
1134 if (asoc->base.dead)
1135 break;
1136
1137 /* If there is an error on chunk, discard this packet. */
1138 if (error && chunk)
1139 chunk->pdiscard = 1;
1140 }
1141 sctp_association_put(asoc);
1142}
1143
1144/* This routine moves an association from its old sk to a new sk. */
1145void sctp_assoc_migrate(struct sctp_association *assoc, struct sock *newsk)
1146{
1147 struct sctp_sock *newsp = sctp_sk(newsk);
1148 struct sock *oldsk = assoc->base.sk;
1149
1150 /* Delete the association from the old endpoint's list of
1151 * associations.
1152 */
1153 list_del_init(&assoc->asocs);
1154
1155 /* Decrement the backlog value for a TCP-style socket. */
1156 if (sctp_style(oldsk, TCP))
1157 oldsk->sk_ack_backlog--;
1158
1159 /* Release references to the old endpoint and the sock. */
1160 sctp_endpoint_put(assoc->ep);
1161 sock_put(assoc->base.sk);
1162
1163 /* Get a reference to the new endpoint. */
1164 assoc->ep = newsp->ep;
1165 sctp_endpoint_hold(assoc->ep);
1166
1167 /* Get a reference to the new sock. */
1168 assoc->base.sk = newsk;
1169 sock_hold(assoc->base.sk);
1170
1171 /* Add the association to the new endpoint's list of associations. */
1172 sctp_endpoint_add_asoc(newsp->ep, assoc);
1173}
1174
1175/* Update an association (possibly from unexpected COOKIE-ECHO processing). */
1176void sctp_assoc_update(struct sctp_association *asoc,
1177 struct sctp_association *new)
1178{
1179 struct sctp_transport *trans;
1180 struct list_head *pos, *temp;
1181
1182 /* Copy in new parameters of peer. */
1183 asoc->c = new->c;
1184 asoc->peer.rwnd = new->peer.rwnd;
1185 asoc->peer.sack_needed = new->peer.sack_needed;
1186 asoc->peer.i = new->peer.i;
Vlad Yasevich8e1ee182008-10-08 14:18:39 -07001187 sctp_tsnmap_init(&asoc->peer.tsn_map, SCTP_TSN_MAP_INITIAL,
1188 asoc->peer.i.initial_tsn, GFP_ATOMIC);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001189
1190 /* Remove any peer addresses not present in the new association. */
1191 list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
1192 trans = list_entry(pos, struct sctp_transport, transports);
Vlad Yasevich0c427492010-04-28 08:47:19 +00001193 if (!sctp_assoc_lookup_paddr(new, &trans->ipaddr)) {
1194 sctp_assoc_rm_peer(asoc, trans);
1195 continue;
1196 }
Vlad Yasevich749bf922007-03-19 17:02:30 -07001197
1198 if (asoc->state >= SCTP_STATE_ESTABLISHED)
1199 sctp_transport_reset(trans);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001200 }
1201
1202 /* If the case is A (association restart), use
1203 * initial_tsn as next_tsn. If the case is B, use
1204 * current next_tsn in case data sent to peer
1205 * has been discarded and needs retransmission.
1206 */
1207 if (asoc->state >= SCTP_STATE_ESTABLISHED) {
1208 asoc->next_tsn = new->next_tsn;
1209 asoc->ctsn_ack_point = new->ctsn_ack_point;
1210 asoc->adv_peer_ack_point = new->adv_peer_ack_point;
1211
1212 /* Reinitialize SSN for both local streams
1213 * and peer's streams.
1214 */
1215 sctp_ssnmap_clear(asoc->ssnmap);
1216
Vlad Yasevich0b58a812007-03-19 17:01:17 -07001217 /* Flush the ULP reassembly and ordered queue.
1218 * Any data there will now be stale and will
1219 * cause problems.
1220 */
1221 sctp_ulpq_flush(&asoc->ulpq);
1222
Vlad Yasevich749bf922007-03-19 17:02:30 -07001223 /* reset the overall association error count so
1224 * that the restarted association doesn't get torn
1225 * down on the next retransmission timer.
1226 */
1227 asoc->overall_error_count = 0;
1228
Linus Torvalds1da177e2005-04-16 15:20:36 -07001229 } else {
1230 /* Add any peer addresses from the new association. */
Robert P. J. Day9dbc15f2008-04-12 18:54:24 -07001231 list_for_each_entry(trans, &new->peer.transport_addr_list,
1232 transports) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001233 if (!sctp_assoc_lookup_paddr(asoc, &trans->ipaddr))
1234 sctp_assoc_add_peer(asoc, &trans->ipaddr,
Sridhar Samudralaad8fec12006-07-21 14:48:50 -07001235 GFP_ATOMIC, trans->state);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001236 }
1237
1238 asoc->ctsn_ack_point = asoc->next_tsn - 1;
1239 asoc->adv_peer_ack_point = asoc->ctsn_ack_point;
1240 if (!asoc->ssnmap) {
1241 /* Move the ssnmap. */
1242 asoc->ssnmap = new->ssnmap;
1243 new->ssnmap = NULL;
1244 }
Vlad Yasevich07d93962007-05-04 13:55:27 -07001245
1246 if (!asoc->assoc_id) {
1247 /* get a new association id since we don't have one
1248 * yet.
1249 */
1250 sctp_assoc_set_id(asoc, GFP_ATOMIC);
1251 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001252 }
Vlad Yasevicha29a5bd2007-09-16 19:31:35 -07001253
Vlad Yasevich730fc3d2007-09-16 19:32:11 -07001254 /* SCTP-AUTH: Save the peer parameters from the new assocaitions
1255 * and also move the association shared keys over
1256 */
1257 kfree(asoc->peer.peer_random);
1258 asoc->peer.peer_random = new->peer.peer_random;
1259 new->peer.peer_random = NULL;
1260
1261 kfree(asoc->peer.peer_chunks);
1262 asoc->peer.peer_chunks = new->peer.peer_chunks;
1263 new->peer.peer_chunks = NULL;
1264
1265 kfree(asoc->peer.peer_hmacs);
1266 asoc->peer.peer_hmacs = new->peer.peer_hmacs;
1267 new->peer.peer_hmacs = NULL;
1268
1269 sctp_auth_key_put(asoc->asoc_shared_key);
1270 sctp_auth_asoc_init_active_key(asoc, GFP_ATOMIC);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001271}
1272
1273/* Update the retran path for sending a retransmitted packet.
1274 * Round-robin through the active transports, else round-robin
1275 * through the inactive transports as this is the next best thing
1276 * we can try.
1277 */
1278void sctp_assoc_update_retran_path(struct sctp_association *asoc)
1279{
1280 struct sctp_transport *t, *next;
1281 struct list_head *head = &asoc->peer.transport_addr_list;
1282 struct list_head *pos;
1283
Gui Jianfeng4141ddc2008-06-04 12:37:33 -07001284 if (asoc->peer.transport_count == 1)
1285 return;
1286
Linus Torvalds1da177e2005-04-16 15:20:36 -07001287 /* Find the next transport in a round-robin fashion. */
1288 t = asoc->peer.retran_path;
1289 pos = &t->transports;
1290 next = NULL;
1291
1292 while (1) {
1293 /* Skip the head. */
1294 if (pos->next == head)
1295 pos = head->next;
1296 else
1297 pos = pos->next;
1298
1299 t = list_entry(pos, struct sctp_transport, transports);
1300
Gui Jianfeng4141ddc2008-06-04 12:37:33 -07001301 /* We have exhausted the list, but didn't find any
1302 * other active transports. If so, use the next
1303 * transport.
1304 */
1305 if (t == asoc->peer.retran_path) {
1306 t = next;
1307 break;
1308 }
1309
Linus Torvalds1da177e2005-04-16 15:20:36 -07001310 /* Try to find an active transport. */
1311
Sridhar Samudralaad8fec12006-07-21 14:48:50 -07001312 if ((t->state == SCTP_ACTIVE) ||
1313 (t->state == SCTP_UNKNOWN)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001314 break;
1315 } else {
1316 /* Keep track of the next transport in case
1317 * we don't find any active transport.
1318 */
Vlad Yasevichfbdf5012010-04-30 22:39:26 -04001319 if (t->state != SCTP_UNCONFIRMED && !next)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001320 next = t;
1321 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001322 }
1323
Vlad Yasevichd598b162010-04-30 22:41:09 -04001324 if (t)
1325 asoc->peer.retran_path = t;
Vlad Yasevich25f7bf72011-04-12 15:20:48 +00001326 else
1327 t = asoc->peer.retran_path;
Frank Filz3f7a87d2005-06-20 13:14:57 -07001328
1329 SCTP_DEBUG_PRINTK_IPADDR("sctp_assoc_update_retran_path:association"
1330 " %p addr: ",
1331 " port: %d\n",
1332 asoc,
1333 (&t->ipaddr),
Al Virob3f5b3b2006-11-20 17:22:43 -08001334 ntohs(t->ipaddr.v4.sin_port));
Frank Filz3f7a87d2005-06-20 13:14:57 -07001335}
1336
Wei Yongjun9919b452009-05-12 21:52:51 +08001337/* Choose the transport for sending retransmit packet. */
1338struct sctp_transport *sctp_assoc_choose_alter_transport(
1339 struct sctp_association *asoc, struct sctp_transport *last_sent_to)
Frank Filz3f7a87d2005-06-20 13:14:57 -07001340{
Wei Yongjun9919b452009-05-12 21:52:51 +08001341 /* If this is the first time packet is sent, use the active path,
1342 * else use the retran path. If the last packet was sent over the
Frank Filz3f7a87d2005-06-20 13:14:57 -07001343 * retran path, update the retran path and use it.
1344 */
Wei Yongjun9919b452009-05-12 21:52:51 +08001345 if (!last_sent_to)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001346 return asoc->peer.active_path;
1347 else {
Wei Yongjun9919b452009-05-12 21:52:51 +08001348 if (last_sent_to == asoc->peer.retran_path)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001349 sctp_assoc_update_retran_path(asoc);
1350 return asoc->peer.retran_path;
1351 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001352}
1353
1354/* Update the association's pmtu and frag_point by going through all the
1355 * transports. This routine is called when a transport's PMTU has changed.
1356 */
1357void sctp_assoc_sync_pmtu(struct sctp_association *asoc)
1358{
1359 struct sctp_transport *t;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001360 __u32 pmtu = 0;
1361
1362 if (!asoc)
1363 return;
1364
1365 /* Get the lowest pmtu of all the transports. */
Robert P. J. Day9dbc15f2008-04-12 18:54:24 -07001366 list_for_each_entry(t, &asoc->peer.transport_addr_list,
1367 transports) {
Vlad Yasevich8a479492007-06-07 14:21:05 -04001368 if (t->pmtu_pending && t->dst) {
1369 sctp_transport_update_pmtu(t, dst_mtu(t->dst));
1370 t->pmtu_pending = 0;
1371 }
Frank Filz52ccb8e2005-12-22 11:36:46 -08001372 if (!pmtu || (t->pathmtu < pmtu))
1373 pmtu = t->pathmtu;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001374 }
1375
1376 if (pmtu) {
Frank Filz52ccb8e2005-12-22 11:36:46 -08001377 asoc->pathmtu = pmtu;
Vlad Yasevichf68b2e02009-09-04 18:21:00 -04001378 asoc->frag_point = sctp_frag_point(asoc, pmtu);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001379 }
1380
1381 SCTP_DEBUG_PRINTK("%s: asoc:%p, pmtu:%d, frag_point:%d\n",
Harvey Harrison0dc47872008-03-05 20:47:47 -08001382 __func__, asoc, asoc->pathmtu, asoc->frag_point);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001383}
1384
1385/* Should we send a SACK to update our peer? */
1386static inline int sctp_peer_needs_update(struct sctp_association *asoc)
1387{
1388 switch (asoc->state) {
1389 case SCTP_STATE_ESTABLISHED:
1390 case SCTP_STATE_SHUTDOWN_PENDING:
1391 case SCTP_STATE_SHUTDOWN_RECEIVED:
1392 case SCTP_STATE_SHUTDOWN_SENT:
1393 if ((asoc->rwnd > asoc->a_rwnd) &&
Vlad Yasevich90f2f532009-11-23 15:53:57 -05001394 ((asoc->rwnd - asoc->a_rwnd) >= max_t(__u32,
1395 (asoc->base.sk->sk_rcvbuf >> sctp_rwnd_upd_shift),
1396 asoc->pathmtu)))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001397 return 1;
1398 break;
1399 default:
1400 break;
1401 }
1402 return 0;
1403}
1404
1405/* Increase asoc's rwnd by len and send any window update SACK if needed. */
1406void sctp_assoc_rwnd_increase(struct sctp_association *asoc, unsigned len)
1407{
1408 struct sctp_chunk *sack;
1409 struct timer_list *timer;
1410
1411 if (asoc->rwnd_over) {
1412 if (asoc->rwnd_over >= len) {
1413 asoc->rwnd_over -= len;
1414 } else {
1415 asoc->rwnd += (len - asoc->rwnd_over);
1416 asoc->rwnd_over = 0;
1417 }
1418 } else {
1419 asoc->rwnd += len;
1420 }
1421
Vlad Yasevich4d3c46e2009-09-04 18:20:59 -04001422 /* If we had window pressure, start recovering it
1423 * once our rwnd had reached the accumulated pressure
1424 * threshold. The idea is to recover slowly, but up
1425 * to the initial advertised window.
1426 */
1427 if (asoc->rwnd_press && asoc->rwnd >= asoc->rwnd_press) {
1428 int change = min(asoc->pathmtu, asoc->rwnd_press);
1429 asoc->rwnd += change;
1430 asoc->rwnd_press -= change;
1431 }
1432
Linus Torvalds1da177e2005-04-16 15:20:36 -07001433 SCTP_DEBUG_PRINTK("%s: asoc %p rwnd increased by %d to (%u, %u) "
Harvey Harrison0dc47872008-03-05 20:47:47 -08001434 "- %u\n", __func__, asoc, len, asoc->rwnd,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001435 asoc->rwnd_over, asoc->a_rwnd);
1436
1437 /* Send a window update SACK if the rwnd has increased by at least the
1438 * minimum of the association's PMTU and half of the receive buffer.
1439 * The algorithm used is similar to the one described in
1440 * Section 4.2.3.3 of RFC 1122.
1441 */
1442 if (sctp_peer_needs_update(asoc)) {
1443 asoc->a_rwnd = asoc->rwnd;
1444 SCTP_DEBUG_PRINTK("%s: Sending window update SACK- asoc: %p "
Harvey Harrison0dc47872008-03-05 20:47:47 -08001445 "rwnd: %u a_rwnd: %u\n", __func__,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001446 asoc, asoc->rwnd, asoc->a_rwnd);
1447 sack = sctp_make_sack(asoc);
1448 if (!sack)
1449 return;
1450
1451 asoc->peer.sack_needed = 0;
1452
1453 sctp_outq_tail(&asoc->outqueue, sack);
1454
1455 /* Stop the SACK timer. */
1456 timer = &asoc->timers[SCTP_EVENT_TIMEOUT_SACK];
1457 if (timer_pending(timer) && del_timer(timer))
1458 sctp_association_put(asoc);
1459 }
1460}
1461
1462/* Decrease asoc's rwnd by len. */
1463void sctp_assoc_rwnd_decrease(struct sctp_association *asoc, unsigned len)
1464{
Vlad Yasevich4d3c46e2009-09-04 18:20:59 -04001465 int rx_count;
1466 int over = 0;
1467
Linus Torvalds1da177e2005-04-16 15:20:36 -07001468 SCTP_ASSERT(asoc->rwnd, "rwnd zero", return);
1469 SCTP_ASSERT(!asoc->rwnd_over, "rwnd_over not zero", return);
Vlad Yasevich4d3c46e2009-09-04 18:20:59 -04001470
1471 if (asoc->ep->rcvbuf_policy)
1472 rx_count = atomic_read(&asoc->rmem_alloc);
1473 else
1474 rx_count = atomic_read(&asoc->base.sk->sk_rmem_alloc);
1475
1476 /* If we've reached or overflowed our receive buffer, announce
1477 * a 0 rwnd if rwnd would still be positive. Store the
1478 * the pottential pressure overflow so that the window can be restored
1479 * back to original value.
1480 */
1481 if (rx_count >= asoc->base.sk->sk_rcvbuf)
1482 over = 1;
1483
Linus Torvalds1da177e2005-04-16 15:20:36 -07001484 if (asoc->rwnd >= len) {
1485 asoc->rwnd -= len;
Vlad Yasevich4d3c46e2009-09-04 18:20:59 -04001486 if (over) {
Vlad Yasevich65883372010-04-30 22:41:10 -04001487 asoc->rwnd_press += asoc->rwnd;
Vlad Yasevich4d3c46e2009-09-04 18:20:59 -04001488 asoc->rwnd = 0;
1489 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001490 } else {
1491 asoc->rwnd_over = len - asoc->rwnd;
1492 asoc->rwnd = 0;
1493 }
Vlad Yasevich4d3c46e2009-09-04 18:20:59 -04001494 SCTP_DEBUG_PRINTK("%s: asoc %p rwnd decreased by %d to (%u, %u, %u)\n",
Harvey Harrison0dc47872008-03-05 20:47:47 -08001495 __func__, asoc, len, asoc->rwnd,
Vlad Yasevich4d3c46e2009-09-04 18:20:59 -04001496 asoc->rwnd_over, asoc->rwnd_press);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001497}
1498
1499/* Build the bind address list for the association based on info from the
1500 * local endpoint and the remote peer.
1501 */
Alexey Dobriyan3182cd842005-07-11 20:57:47 -07001502int sctp_assoc_set_bind_addr_from_ep(struct sctp_association *asoc,
Vlad Yasevich409b95a2009-11-10 08:57:34 +00001503 sctp_scope_t scope, gfp_t gfp)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001504{
Linus Torvalds1da177e2005-04-16 15:20:36 -07001505 int flags;
1506
1507 /* Use scoping rules to determine the subset of addresses from
1508 * the endpoint.
1509 */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001510 flags = (PF_INET6 == asoc->base.sk->sk_family) ? SCTP_ADDR6_ALLOWED : 0;
1511 if (asoc->peer.ipv4_address)
1512 flags |= SCTP_ADDR4_PEERSUPP;
1513 if (asoc->peer.ipv6_address)
1514 flags |= SCTP_ADDR6_PEERSUPP;
1515
1516 return sctp_bind_addr_copy(&asoc->base.bind_addr,
1517 &asoc->ep->base.bind_addr,
1518 scope, gfp, flags);
1519}
1520
1521/* Build the association's bind address list from the cookie. */
1522int sctp_assoc_set_bind_addr_from_cookie(struct sctp_association *asoc,
Alexey Dobriyan3182cd842005-07-11 20:57:47 -07001523 struct sctp_cookie *cookie,
Al Virodd0fc662005-10-07 07:46:04 +01001524 gfp_t gfp)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001525{
1526 int var_size2 = ntohs(cookie->peer_init->chunk_hdr.length);
1527 int var_size3 = cookie->raw_addr_list_len;
1528 __u8 *raw = (__u8 *)cookie->peer_init + var_size2;
1529
1530 return sctp_raw_to_bind_addrs(&asoc->base.bind_addr, raw, var_size3,
1531 asoc->ep->base.bind_addr.port, gfp);
1532}
1533
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +09001534/* Lookup laddr in the bind address list of an association. */
1535int sctp_assoc_lookup_laddr(struct sctp_association *asoc,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001536 const union sctp_addr *laddr)
1537{
Vlad Yasevich559cf712007-09-16 16:03:28 -07001538 int found = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001539
Linus Torvalds1da177e2005-04-16 15:20:36 -07001540 if ((asoc->base.bind_addr.port == ntohs(laddr->v4.sin_port)) &&
1541 sctp_bind_addr_match(&asoc->base.bind_addr, laddr,
Vlad Yasevich559cf712007-09-16 16:03:28 -07001542 sctp_sk(asoc->base.sk)))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001543 found = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001544
Linus Torvalds1da177e2005-04-16 15:20:36 -07001545 return found;
1546}
Vlad Yasevich07d93962007-05-04 13:55:27 -07001547
1548/* Set an association id for a given association */
1549int sctp_assoc_set_id(struct sctp_association *asoc, gfp_t gfp)
1550{
1551 int assoc_id;
1552 int error = 0;
Vlad Yasevichc6ba68a2009-06-01 12:41:15 -04001553
1554 /* If the id is already assigned, keep it. */
1555 if (asoc->assoc_id)
1556 return error;
Vlad Yasevich07d93962007-05-04 13:55:27 -07001557retry:
1558 if (unlikely(!idr_pre_get(&sctp_assocs_id, gfp)))
1559 return -ENOMEM;
1560
1561 spin_lock_bh(&sctp_assocs_id_lock);
1562 error = idr_get_new_above(&sctp_assocs_id, (void *)asoc,
Vlad Yasevich48143262009-11-23 15:54:01 -05001563 idr_low, &assoc_id);
1564 if (!error) {
1565 idr_low = assoc_id + 1;
1566 if (idr_low == INT_MAX)
1567 idr_low = 1;
1568 }
Vlad Yasevich07d93962007-05-04 13:55:27 -07001569 spin_unlock_bh(&sctp_assocs_id_lock);
1570 if (error == -EAGAIN)
1571 goto retry;
1572 else if (error)
1573 return error;
1574
1575 asoc->assoc_id = (sctp_assoc_t) assoc_id;
1576 return error;
1577}
Vlad Yasevicha08de642007-12-20 14:11:47 -08001578
1579/* Free asconf_ack cache */
1580static void sctp_assoc_free_asconf_acks(struct sctp_association *asoc)
1581{
1582 struct sctp_chunk *ack;
1583 struct sctp_chunk *tmp;
1584
1585 list_for_each_entry_safe(ack, tmp, &asoc->asconf_ack_list,
1586 transmitted_list) {
1587 list_del_init(&ack->transmitted_list);
1588 sctp_chunk_free(ack);
1589 }
1590}
1591
1592/* Clean up the ASCONF_ACK queue */
1593void sctp_assoc_clean_asconf_ack_cache(const struct sctp_association *asoc)
1594{
1595 struct sctp_chunk *ack;
1596 struct sctp_chunk *tmp;
1597
Lucas De Marchi25985ed2011-03-30 22:57:33 -03001598 /* We can remove all the entries from the queue up to
Vlad Yasevicha08de642007-12-20 14:11:47 -08001599 * the "Peer-Sequence-Number".
1600 */
1601 list_for_each_entry_safe(ack, tmp, &asoc->asconf_ack_list,
1602 transmitted_list) {
1603 if (ack->subh.addip_hdr->serial ==
1604 htonl(asoc->peer.addip_serial))
1605 break;
1606
1607 list_del_init(&ack->transmitted_list);
1608 sctp_chunk_free(ack);
1609 }
1610}
1611
1612/* Find the ASCONF_ACK whose serial number matches ASCONF */
1613struct sctp_chunk *sctp_assoc_lookup_asconf_ack(
1614 const struct sctp_association *asoc,
1615 __be32 serial)
1616{
Wei Yongjuna8699812008-02-05 23:35:04 +09001617 struct sctp_chunk *ack;
Vlad Yasevicha08de642007-12-20 14:11:47 -08001618
1619 /* Walk through the list of cached ASCONF-ACKs and find the
1620 * ack chunk whose serial number matches that of the request.
1621 */
1622 list_for_each_entry(ack, &asoc->asconf_ack_list, transmitted_list) {
1623 if (ack->subh.addip_hdr->serial == serial) {
1624 sctp_chunk_hold(ack);
Wei Yongjuna8699812008-02-05 23:35:04 +09001625 return ack;
Vlad Yasevicha08de642007-12-20 14:11:47 -08001626 }
1627 }
1628
Wei Yongjuna8699812008-02-05 23:35:04 +09001629 return NULL;
Vlad Yasevicha08de642007-12-20 14:11:47 -08001630}