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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
Linus Torvalds1da177e2005-04-16 15:20:36 -070069/* 1st Level Abstractions. */
70
71/* Initialize a new association from provided memory. */
72static struct sctp_association *sctp_association_init(struct sctp_association *asoc,
73 const struct sctp_endpoint *ep,
74 const struct sock *sk,
75 sctp_scope_t scope,
Al Virodd0fc662005-10-07 07:46:04 +010076 gfp_t gfp)
Linus Torvalds1da177e2005-04-16 15:20:36 -070077{
Eric W. Biedermane1fc3b12012-08-07 07:29:57 +000078 struct net *net = sock_net(sk);
Linus Torvalds1da177e2005-04-16 15:20:36 -070079 struct sctp_sock *sp;
80 int i;
Vlad Yasevicha29a5bd2007-09-16 19:31:35 -070081 sctp_paramhdr_t *p;
82 int err;
Linus Torvalds1da177e2005-04-16 15:20:36 -070083
84 /* Retrieve the SCTP per socket area. */
85 sp = sctp_sk((struct sock *)sk);
86
Linus Torvalds1da177e2005-04-16 15:20:36 -070087 /* Discarding const is appropriate here. */
88 asoc->ep = (struct sctp_endpoint *)ep;
Linus Torvalds1da177e2005-04-16 15:20:36 -070089 asoc->base.sk = (struct sock *)sk;
Daniel Borkmann2e0c9e72013-06-14 18:24:07 +020090
91 sctp_endpoint_hold(asoc->ep);
Linus Torvalds1da177e2005-04-16 15:20:36 -070092 sock_hold(asoc->base.sk);
93
94 /* Initialize the common base substructure. */
95 asoc->base.type = SCTP_EP_TYPE_ASSOCIATION;
96
97 /* Initialize the object handling fields. */
98 atomic_set(&asoc->base.refcnt, 1);
Daniel Borkmann0022d2d2013-04-15 03:27:18 +000099 asoc->base.dead = false;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700100
101 /* Initialize the bind addr area. */
102 sctp_bind_addr_init(&asoc->base.bind_addr, ep->base.bind_addr.port);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700103
104 asoc->state = SCTP_STATE_CLOSED;
Daniel Borkmann52db8822013-06-25 18:17:27 +0200105 asoc->cookie_life = ms_to_ktime(sp->assocparams.sasoc_cookie_life);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700106 asoc->frag_point = 0;
Vlad Yasevichf68b2e02009-09-04 18:21:00 -0400107 asoc->user_frag = sp->user_frag;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700108
109 /* Set the association max_retrans and RTO values from the
110 * socket values.
111 */
112 asoc->max_retrans = sp->assocparams.sasoc_asocmaxrxt;
Eric W. Biedermane1fc3b12012-08-07 07:29:57 +0000113 asoc->pf_retrans = net->sctp.pf_retrans;
Neil Horman5aa93bc2012-07-21 07:56:07 +0000114
Linus Torvalds1da177e2005-04-16 15:20:36 -0700115 asoc->rto_initial = msecs_to_jiffies(sp->rtoinfo.srto_initial);
116 asoc->rto_max = msecs_to_jiffies(sp->rtoinfo.srto_max);
117 asoc->rto_min = msecs_to_jiffies(sp->rtoinfo.srto_min);
118
119 asoc->overall_error_count = 0;
120
Frank Filz52ccb8e2005-12-22 11:36:46 -0800121 /* Initialize the association's heartbeat interval based on the
122 * sock configured value.
123 */
124 asoc->hbinterval = msecs_to_jiffies(sp->hbinterval);
125
126 /* Initialize path max retrans value. */
127 asoc->pathmaxrxt = sp->pathmaxrxt;
128
129 /* Initialize default path MTU. */
130 asoc->pathmtu = sp->pathmtu;
131
132 /* Set association default SACK delay */
133 asoc->sackdelay = msecs_to_jiffies(sp->sackdelay);
Wei Yongjund364d922008-05-09 15:13:26 -0700134 asoc->sackfreq = sp->sackfreq;
Frank Filz52ccb8e2005-12-22 11:36:46 -0800135
136 /* Set the association default flags controlling
137 * Heartbeat, SACK delay, and Path MTU Discovery.
138 */
139 asoc->param_flags = sp->param_flags;
140
Linus Torvalds1da177e2005-04-16 15:20:36 -0700141 /* Initialize the maximum mumber of new data packets that can be sent
142 * in a burst.
143 */
Vlad Yasevich70331572007-03-23 11:34:36 -0700144 asoc->max_burst = sp->max_burst;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700145
Vladislav Yasevich1e7d3d92005-11-11 16:06:16 -0800146 /* initialize association timers */
147 asoc->timeouts[SCTP_EVENT_TIMEOUT_NONE] = 0;
148 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_COOKIE] = asoc->rto_initial;
149 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_INIT] = asoc->rto_initial;
150 asoc->timeouts[SCTP_EVENT_TIMEOUT_T2_SHUTDOWN] = asoc->rto_initial;
151 asoc->timeouts[SCTP_EVENT_TIMEOUT_T3_RTX] = 0;
152 asoc->timeouts[SCTP_EVENT_TIMEOUT_T4_RTO] = 0;
153
154 /* sctpimpguide Section 2.12.2
155 * If the 'T5-shutdown-guard' timer is used, it SHOULD be set to the
156 * recommended value of 5 times 'RTO.Max'.
157 */
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +0900158 asoc->timeouts[SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD]
Vladislav Yasevich1e7d3d92005-11-11 16:06:16 -0800159 = 5 * asoc->rto_max;
160
161 asoc->timeouts[SCTP_EVENT_TIMEOUT_HEARTBEAT] = 0;
Frank Filz52ccb8e2005-12-22 11:36:46 -0800162 asoc->timeouts[SCTP_EVENT_TIMEOUT_SACK] = asoc->sackdelay;
Vladislav Yasevich1e7d3d92005-11-11 16:06:16 -0800163 asoc->timeouts[SCTP_EVENT_TIMEOUT_AUTOCLOSE] =
Eric W. Biedermane1fc3b12012-08-07 07:29:57 +0000164 min_t(unsigned long, sp->autoclose, net->sctp.max_autoclose) * HZ;
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +0900165
Uwe Kleine-König421f91d2010-06-11 12:17:00 +0200166 /* Initializes the timers */
Pavel Emelyanovb24b8a22008-01-23 21:20:07 -0800167 for (i = SCTP_EVENT_TIMEOUT_NONE; i < SCTP_NUM_TIMEOUT_TYPES; ++i)
168 setup_timer(&asoc->timers[i], sctp_timer_events[i],
169 (unsigned long)asoc);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700170
171 /* Pull default initialization values from the sock options.
172 * Note: This assumes that the values have already been
173 * validated in the sock.
174 */
175 asoc->c.sinit_max_instreams = sp->initmsg.sinit_max_instreams;
176 asoc->c.sinit_num_ostreams = sp->initmsg.sinit_num_ostreams;
177 asoc->max_init_attempts = sp->initmsg.sinit_max_attempts;
178
179 asoc->max_init_timeo =
180 msecs_to_jiffies(sp->initmsg.sinit_max_init_timeo);
181
182 /* Allocate storage for the ssnmap after the inbound and outbound
183 * streams have been negotiated during Init.
184 */
185 asoc->ssnmap = NULL;
186
187 /* Set the local window size for receive.
188 * This is also the rcvbuf space per association.
189 * RFC 6 - A SCTP receiver MUST be able to receive a minimum of
190 * 1500 bytes in one SCTP packet.
191 */
Neil Horman049b3ff2005-11-11 16:08:24 -0800192 if ((sk->sk_rcvbuf/2) < SCTP_DEFAULT_MINWINDOW)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700193 asoc->rwnd = SCTP_DEFAULT_MINWINDOW;
194 else
Neil Horman049b3ff2005-11-11 16:08:24 -0800195 asoc->rwnd = sk->sk_rcvbuf/2;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700196
197 asoc->a_rwnd = asoc->rwnd;
198
199 asoc->rwnd_over = 0;
Vlad Yasevich4d3c46e2009-09-04 18:20:59 -0400200 asoc->rwnd_press = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700201
202 /* Use my own max window until I learn something better. */
203 asoc->peer.rwnd = SCTP_DEFAULT_MAXWINDOW;
204
205 /* Set the sndbuf size for transmit. */
206 asoc->sndbuf_used = 0;
207
Neil Horman049b3ff2005-11-11 16:08:24 -0800208 /* Initialize the receive memory counter */
209 atomic_set(&asoc->rmem_alloc, 0);
210
Linus Torvalds1da177e2005-04-16 15:20:36 -0700211 init_waitqueue_head(&asoc->wait);
212
213 asoc->c.my_vtag = sctp_generate_tag(ep);
214 asoc->peer.i.init_tag = 0; /* INIT needs a vtag of 0. */
215 asoc->c.peer_vtag = 0;
216 asoc->c.my_ttag = 0;
217 asoc->c.peer_ttag = 0;
218 asoc->c.my_port = ep->base.bind_addr.port;
219
220 asoc->c.initial_tsn = sctp_generate_tsn(ep);
221
222 asoc->next_tsn = asoc->c.initial_tsn;
223
224 asoc->ctsn_ack_point = asoc->next_tsn - 1;
225 asoc->adv_peer_ack_point = asoc->ctsn_ack_point;
226 asoc->highest_sacked = asoc->ctsn_ack_point;
227 asoc->last_cwr_tsn = asoc->ctsn_ack_point;
228 asoc->unack_data = 0;
229
Linus Torvalds1da177e2005-04-16 15:20:36 -0700230 /* ADDIP Section 4.1 Asconf Chunk Procedures
231 *
232 * When an endpoint has an ASCONF signaled change to be sent to the
233 * remote endpoint it should do the following:
234 * ...
235 * A2) a serial number should be assigned to the chunk. The serial
236 * number SHOULD be a monotonically increasing number. The serial
237 * numbers SHOULD be initialized at the start of the
238 * association to the same value as the initial TSN.
239 */
240 asoc->addip_serial = asoc->c.initial_tsn;
241
David S. Miller79af02c2005-07-08 21:47:49 -0700242 INIT_LIST_HEAD(&asoc->addip_chunk_list);
Vlad Yasevicha08de642007-12-20 14:11:47 -0800243 INIT_LIST_HEAD(&asoc->asconf_ack_list);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700244
245 /* Make an empty list of remote transport addresses. */
246 INIT_LIST_HEAD(&asoc->peer.transport_addr_list);
Frank Filz3f7a87d2005-06-20 13:14:57 -0700247 asoc->peer.transport_count = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700248
249 /* RFC 2960 5.1 Normal Establishment of an Association
250 *
251 * After the reception of the first data chunk in an
252 * association the endpoint must immediately respond with a
253 * sack to acknowledge the data chunk. Subsequent
254 * acknowledgements should be done as described in Section
255 * 6.2.
256 *
257 * [We implement this by telling a new association that it
258 * already received one packet.]
259 */
260 asoc->peer.sack_needed = 1;
Wei Yongjund364d922008-05-09 15:13:26 -0700261 asoc->peer.sack_cnt = 0;
Neil Horman42448542012-06-30 03:04:26 +0000262 asoc->peer.sack_generation = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700263
Vlad Yasevich73d9c4f2007-10-24 17:24:26 -0400264 /* Assume that the peer will tell us if he recognizes ASCONF
265 * as part of INIT exchange.
266 * The sctp_addip_noauth option is there for backward compatibilty
267 * and will revert old behavior.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700268 */
Vlad Yasevich88799fe2007-10-24 17:24:23 -0400269 asoc->peer.asconf_capable = 0;
Eric W. Biedermane1fc3b12012-08-07 07:29:57 +0000270 if (net->sctp.addip_noauth)
Vlad Yasevich73d9c4f2007-10-24 17:24:26 -0400271 asoc->peer.asconf_capable = 1;
Michio Honda8a07eb02011-04-26 20:19:36 +0900272 asoc->asconf_addr_del_pending = NULL;
273 asoc->src_out_of_asoc_ok = 0;
Michio Honda6af29cc2011-06-16 17:14:34 +0900274 asoc->new_transport = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700275
276 /* Create an input queue. */
277 sctp_inq_init(&asoc->base.inqueue);
David Howellsc4028952006-11-22 14:57:56 +0000278 sctp_inq_set_th_handler(&asoc->base.inqueue, sctp_assoc_bh_rcv);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700279
280 /* Create an output queue. */
281 sctp_outq_init(asoc, &asoc->outqueue);
282
283 if (!sctp_ulpq_init(&asoc->ulpq, asoc))
284 goto fail_init;
285
Vlad Yasevich8e1ee182008-10-08 14:18:39 -0700286 memset(&asoc->peer.tsn_map, 0, sizeof(struct sctp_tsnmap));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700287
288 asoc->need_ecne = 0;
289
290 asoc->assoc_id = 0;
291
292 /* Assume that peer would support both address types unless we are
293 * told otherwise.
294 */
295 asoc->peer.ipv4_address = 1;
Wei Yongjuna2c39582009-04-07 16:35:11 +0800296 if (asoc->base.sk->sk_family == PF_INET6)
297 asoc->peer.ipv6_address = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700298 INIT_LIST_HEAD(&asoc->asocs);
299
300 asoc->autoclose = sp->autoclose;
301
302 asoc->default_stream = sp->default_stream;
303 asoc->default_ppid = sp->default_ppid;
304 asoc->default_flags = sp->default_flags;
305 asoc->default_context = sp->default_context;
306 asoc->default_timetolive = sp->default_timetolive;
Ivan Skytte Jorgensen6ab792f2006-12-13 16:34:22 -0800307 asoc->default_rcv_context = sp->default_rcv_context;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700308
Michele Baldessari196d6752012-12-01 04:49:42 +0000309 /* SCTP_GET_ASSOC_STATS COUNTERS */
310 memset(&asoc->stats, 0, sizeof(struct sctp_priv_assoc_stats));
311
Vlad Yasevicha29a5bd2007-09-16 19:31:35 -0700312 /* AUTH related initializations */
313 INIT_LIST_HEAD(&asoc->endpoint_shared_keys);
314 err = sctp_auth_asoc_copy_shkeys(ep, asoc, gfp);
315 if (err)
316 goto fail_init;
317
318 asoc->active_key_id = ep->active_key_id;
319 asoc->asoc_shared_key = NULL;
320
321 asoc->default_hmac_id = 0;
322 /* Save the hmacs and chunks list into this association */
323 if (ep->auth_hmacs_list)
324 memcpy(asoc->c.auth_hmacs, ep->auth_hmacs_list,
325 ntohs(ep->auth_hmacs_list->param_hdr.length));
326 if (ep->auth_chunk_list)
327 memcpy(asoc->c.auth_chunks, ep->auth_chunk_list,
328 ntohs(ep->auth_chunk_list->param_hdr.length));
329
330 /* Get the AUTH random number for this association */
331 p = (sctp_paramhdr_t *)asoc->c.auth_random;
332 p->type = SCTP_PARAM_RANDOM;
333 p->length = htons(sizeof(sctp_paramhdr_t) + SCTP_AUTH_RANDOM_LENGTH);
334 get_random_bytes(p+1, SCTP_AUTH_RANDOM_LENGTH);
335
Linus Torvalds1da177e2005-04-16 15:20:36 -0700336 return asoc;
337
338fail_init:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700339 sock_put(asoc->base.sk);
Daniel Borkmann2e0c9e72013-06-14 18:24:07 +0200340 sctp_endpoint_put(asoc->ep);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700341 return NULL;
342}
343
344/* Allocate and initialize a new association */
345struct sctp_association *sctp_association_new(const struct sctp_endpoint *ep,
346 const struct sock *sk,
Alexey Dobriyan3182cd82005-07-11 20:57:47 -0700347 sctp_scope_t scope,
Al Virodd0fc662005-10-07 07:46:04 +0100348 gfp_t gfp)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700349{
350 struct sctp_association *asoc;
351
Daniel Borkmann939cfa72013-06-17 11:40:04 +0200352 asoc = kzalloc(sizeof(*asoc), gfp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700353 if (!asoc)
354 goto fail;
355
356 if (!sctp_association_init(asoc, ep, sk, scope, gfp))
357 goto fail_init;
358
Linus Torvalds1da177e2005-04-16 15:20:36 -0700359 SCTP_DBG_OBJCNT_INC(assoc);
Daniel Borkmannbb333812013-06-28 19:49:40 +0200360
361 pr_debug("Created asoc %p\n", asoc);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700362
363 return asoc;
364
365fail_init:
366 kfree(asoc);
367fail:
368 return NULL;
369}
370
371/* Free this association if possible. There may still be users, so
372 * the actual deallocation may be delayed.
373 */
374void sctp_association_free(struct sctp_association *asoc)
375{
376 struct sock *sk = asoc->base.sk;
377 struct sctp_transport *transport;
378 struct list_head *pos, *temp;
379 int i;
380
Vlad Yasevichde76e692006-10-30 18:55:11 -0800381 /* Only real associations count against the endpoint, so
382 * don't bother for if this is a temporary association.
383 */
384 if (!asoc->temp) {
385 list_del(&asoc->asocs);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700386
Vlad Yasevichde76e692006-10-30 18:55:11 -0800387 /* Decrement the backlog value for a TCP-style listening
388 * socket.
389 */
390 if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING))
391 sk->sk_ack_backlog--;
392 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700393
394 /* Mark as dead, so other users can know this structure is
395 * going away.
396 */
Daniel Borkmann0022d2d2013-04-15 03:27:18 +0000397 asoc->base.dead = true;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700398
399 /* Dispose of any data lying around in the outqueue. */
400 sctp_outq_free(&asoc->outqueue);
401
402 /* Dispose of any pending messages for the upper layer. */
403 sctp_ulpq_free(&asoc->ulpq);
404
405 /* Dispose of any pending chunks on the inqueue. */
406 sctp_inq_free(&asoc->base.inqueue);
407
Vlad Yasevich8e1ee182008-10-08 14:18:39 -0700408 sctp_tsnmap_free(&asoc->peer.tsn_map);
409
Linus Torvalds1da177e2005-04-16 15:20:36 -0700410 /* Free ssnmap storage. */
411 sctp_ssnmap_free(asoc->ssnmap);
412
413 /* Clean up the bound address list. */
414 sctp_bind_addr_free(&asoc->base.bind_addr);
415
416 /* Do we need to go through all of our timers and
417 * delete them? To be safe we will try to delete all, but we
418 * should be able to go through and make a guess based
419 * on our state.
420 */
421 for (i = SCTP_EVENT_TIMEOUT_NONE; i < SCTP_NUM_TIMEOUT_TYPES; ++i) {
Ying Xue25cc4ae2013-02-03 20:32:57 +0000422 if (del_timer(&asoc->timers[i]))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700423 sctp_association_put(asoc);
424 }
425
426 /* Free peer's cached cookie. */
Jesper Juhla51482b2005-11-08 09:41:34 -0800427 kfree(asoc->peer.cookie);
Vlad Yasevich730fc3d2007-09-16 19:32:11 -0700428 kfree(asoc->peer.peer_random);
429 kfree(asoc->peer.peer_chunks);
430 kfree(asoc->peer.peer_hmacs);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700431
432 /* Release the transport structures. */
433 list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
434 transport = list_entry(pos, struct sctp_transport, transports);
Thomas Graf45122ca262012-12-06 09:25:05 +0000435 list_del_rcu(pos);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700436 sctp_transport_free(transport);
437 }
438
Frank Filz3f7a87d2005-06-20 13:14:57 -0700439 asoc->peer.transport_count = 0;
440
Wei Yongjuna000c012011-05-29 23:23:36 +0000441 sctp_asconf_queue_teardown(asoc);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700442
Michio Honda8a07eb02011-04-26 20:19:36 +0900443 /* Free pending address space being deleted */
444 if (asoc->asconf_addr_del_pending != NULL)
445 kfree(asoc->asconf_addr_del_pending);
446
Vlad Yasevicha29a5bd2007-09-16 19:31:35 -0700447 /* AUTH - Free the endpoint shared keys */
448 sctp_auth_destroy_keys(&asoc->endpoint_shared_keys);
449
450 /* AUTH - Free the association shared key */
451 sctp_auth_key_put(asoc->asoc_shared_key);
452
Linus Torvalds1da177e2005-04-16 15:20:36 -0700453 sctp_association_put(asoc);
454}
455
456/* Cleanup and free up an association. */
457static void sctp_association_destroy(struct sctp_association *asoc)
458{
Daniel Borkmannbb333812013-06-28 19:49:40 +0200459 if (unlikely(!asoc->base.dead)) {
460 WARN(1, "Attempt to destroy undead association %p!\n", asoc);
461 return;
462 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700463
464 sctp_endpoint_put(asoc->ep);
465 sock_put(asoc->base.sk);
466
467 if (asoc->assoc_id != 0) {
468 spin_lock_bh(&sctp_assocs_id_lock);
469 idr_remove(&sctp_assocs_id, asoc->assoc_id);
470 spin_unlock_bh(&sctp_assocs_id_lock);
471 }
472
Ilpo Järvinen547b7922008-07-25 21:43:18 -0700473 WARN_ON(atomic_read(&asoc->rmem_alloc));
Neil Horman049b3ff2005-11-11 16:08:24 -0800474
Daniel Borkmannff2266c2013-04-15 03:27:17 +0000475 kfree(asoc);
476 SCTP_DBG_OBJCNT_DEC(assoc);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700477}
478
479/* Change the primary destination address for the peer. */
480void sctp_assoc_set_primary(struct sctp_association *asoc,
481 struct sctp_transport *transport)
482{
Vlad Yasevich319fa2a2008-06-16 17:00:29 -0700483 int changeover = 0;
484
485 /* it's a changeover only if we already have a primary path
486 * that we are changing
487 */
488 if (asoc->peer.primary_path != NULL &&
489 asoc->peer.primary_path != transport)
490 changeover = 1 ;
491
Linus Torvalds1da177e2005-04-16 15:20:36 -0700492 asoc->peer.primary_path = transport;
493
494 /* Set a default msg_name for events. */
495 memcpy(&asoc->peer.primary_addr, &transport->ipaddr,
496 sizeof(union sctp_addr));
497
498 /* If the primary path is changing, assume that the
499 * user wants to use this new path.
500 */
Sridhar Samudralaad8fec12006-07-21 14:48:50 -0700501 if ((transport->state == SCTP_ACTIVE) ||
502 (transport->state == SCTP_UNKNOWN))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700503 asoc->peer.active_path = transport;
504
505 /*
506 * SFR-CACC algorithm:
507 * Upon the receipt of a request to change the primary
508 * destination address, on the data structure for the new
509 * primary destination, the sender MUST do the following:
510 *
511 * 1) If CHANGEOVER_ACTIVE is set, then there was a switch
512 * to this destination address earlier. The sender MUST set
513 * CYCLING_CHANGEOVER to indicate that this switch is a
514 * double switch to the same destination address.
Vlad Yaseviche0e9db12009-11-23 15:53:57 -0500515 *
516 * Really, only bother is we have data queued or outstanding on
517 * the association.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700518 */
Vlad Yaseviche0e9db12009-11-23 15:53:57 -0500519 if (!asoc->outqueue.outstanding_bytes && !asoc->outqueue.out_qlen)
520 return;
521
Linus Torvalds1da177e2005-04-16 15:20:36 -0700522 if (transport->cacc.changeover_active)
Vlad Yasevich319fa2a2008-06-16 17:00:29 -0700523 transport->cacc.cycling_changeover = changeover;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700524
525 /* 2) The sender MUST set CHANGEOVER_ACTIVE to indicate that
526 * a changeover has occurred.
527 */
Vlad Yasevich319fa2a2008-06-16 17:00:29 -0700528 transport->cacc.changeover_active = changeover;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700529
530 /* 3) The sender MUST store the next TSN to be sent in
531 * next_tsn_at_change.
532 */
533 transport->cacc.next_tsn_at_change = asoc->next_tsn;
534}
535
Frank Filz3f7a87d2005-06-20 13:14:57 -0700536/* Remove a transport from an association. */
537void sctp_assoc_rm_peer(struct sctp_association *asoc,
538 struct sctp_transport *peer)
539{
540 struct list_head *pos;
541 struct sctp_transport *transport;
542
Daniel Borkmannbb333812013-06-28 19:49:40 +0200543 pr_debug("%s: association:%p addr:%pISpc\n",
544 __func__, asoc, &peer->ipaddr.sa);
Frank Filz3f7a87d2005-06-20 13:14:57 -0700545
546 /* If we are to remove the current retran_path, update it
547 * to the next peer before removing this peer from the list.
548 */
549 if (asoc->peer.retran_path == peer)
550 sctp_assoc_update_retran_path(asoc);
551
552 /* Remove this peer from the list. */
Thomas Graf45122ca262012-12-06 09:25:05 +0000553 list_del_rcu(&peer->transports);
Frank Filz3f7a87d2005-06-20 13:14:57 -0700554
555 /* Get the first transport of asoc. */
556 pos = asoc->peer.transport_addr_list.next;
557 transport = list_entry(pos, struct sctp_transport, transports);
558
559 /* Update any entries that match the peer to be deleted. */
560 if (asoc->peer.primary_path == peer)
561 sctp_assoc_set_primary(asoc, transport);
562 if (asoc->peer.active_path == peer)
563 asoc->peer.active_path = transport;
Wei Yongjun9494c7c2011-04-12 15:22:22 +0000564 if (asoc->peer.retran_path == peer)
565 asoc->peer.retran_path = transport;
Frank Filz3f7a87d2005-06-20 13:14:57 -0700566 if (asoc->peer.last_data_from == peer)
567 asoc->peer.last_data_from = transport;
568
569 /* If we remove the transport an INIT was last sent to, set it to
570 * NULL. Combined with the update of the retran path above, this
571 * will cause the next INIT to be sent to the next available
572 * transport, maintaining the cycle.
573 */
574 if (asoc->init_last_sent_to == peer)
575 asoc->init_last_sent_to = NULL;
576
Wei Yongjun6345b192009-04-26 23:13:35 +0800577 /* If we remove the transport an SHUTDOWN was last sent to, set it
578 * to NULL. Combined with the update of the retran path above, this
579 * will cause the next SHUTDOWN to be sent to the next available
580 * transport, maintaining the cycle.
581 */
582 if (asoc->shutdown_last_sent_to == peer)
583 asoc->shutdown_last_sent_to = NULL;
584
Wei Yongjun10a43ce2009-04-26 23:14:42 +0800585 /* If we remove the transport an ASCONF was last sent to, set it to
586 * NULL.
587 */
588 if (asoc->addip_last_asconf &&
589 asoc->addip_last_asconf->transport == peer)
590 asoc->addip_last_asconf->transport = NULL;
591
Vlad Yasevich31b02e12009-09-04 18:21:00 -0400592 /* If we have something on the transmitted list, we have to
593 * save it off. The best place is the active path.
594 */
595 if (!list_empty(&peer->transmitted)) {
596 struct sctp_transport *active = asoc->peer.active_path;
597 struct sctp_chunk *ch;
598
599 /* Reset the transport of each chunk on this list */
600 list_for_each_entry(ch, &peer->transmitted,
601 transmitted_list) {
602 ch->transport = NULL;
603 ch->rtt_in_progress = 0;
604 }
605
606 list_splice_tail_init(&peer->transmitted,
607 &active->transmitted);
608
609 /* Start a T3 timer here in case it wasn't running so
610 * that these migrated packets have a chance to get
611 * retrnasmitted.
612 */
613 if (!timer_pending(&active->T3_rtx_timer))
614 if (!mod_timer(&active->T3_rtx_timer,
615 jiffies + active->rto))
616 sctp_transport_hold(active);
617 }
618
Frank Filz3f7a87d2005-06-20 13:14:57 -0700619 asoc->peer.transport_count--;
620
621 sctp_transport_free(peer);
622}
623
Linus Torvalds1da177e2005-04-16 15:20:36 -0700624/* Add a transport address to an association. */
625struct sctp_transport *sctp_assoc_add_peer(struct sctp_association *asoc,
626 const union sctp_addr *addr,
Al Virodd0fc662005-10-07 07:46:04 +0100627 const gfp_t gfp,
Frank Filz3f7a87d2005-06-20 13:14:57 -0700628 const int peer_state)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700629{
Eric W. Biederman89bf3452012-08-07 07:26:14 +0000630 struct net *net = sock_net(asoc->base.sk);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700631 struct sctp_transport *peer;
632 struct sctp_sock *sp;
633 unsigned short port;
634
635 sp = sctp_sk(asoc->base.sk);
636
637 /* AF_INET and AF_INET6 share common port field. */
Al Viro4bdf4b52006-11-20 17:10:20 -0800638 port = ntohs(addr->v4.sin_port);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700639
Daniel Borkmannbb333812013-06-28 19:49:40 +0200640 pr_debug("%s: association:%p addr:%pISpc state:%d\n", __func__,
641 asoc, &addr->sa, peer_state);
Frank Filz3f7a87d2005-06-20 13:14:57 -0700642
Linus Torvalds1da177e2005-04-16 15:20:36 -0700643 /* Set the port if it has not been set yet. */
644 if (0 == asoc->peer.port)
645 asoc->peer.port = port;
646
647 /* Check to see if this is a duplicate. */
648 peer = sctp_assoc_lookup_paddr(asoc, addr);
Frank Filz3f7a87d2005-06-20 13:14:57 -0700649 if (peer) {
Vlad Yasevichadd52372008-09-18 16:28:27 -0700650 /* An UNKNOWN state is only set on transports added by
651 * user in sctp_connectx() call. Such transports should be
652 * considered CONFIRMED per RFC 4960, Section 5.4.
653 */
Sridhar Samudralaad8fec12006-07-21 14:48:50 -0700654 if (peer->state == SCTP_UNKNOWN) {
Vlad Yasevichadd52372008-09-18 16:28:27 -0700655 peer->state = SCTP_ACTIVE;
Sridhar Samudralaad8fec12006-07-21 14:48:50 -0700656 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700657 return peer;
Frank Filz3f7a87d2005-06-20 13:14:57 -0700658 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700659
Eric W. Biederman89bf3452012-08-07 07:26:14 +0000660 peer = sctp_transport_new(net, addr, gfp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700661 if (!peer)
662 return NULL;
663
664 sctp_transport_set_owner(peer, asoc);
665
Frank Filz52ccb8e2005-12-22 11:36:46 -0800666 /* Initialize the peer's heartbeat interval based on the
667 * association configured value.
668 */
669 peer->hbinterval = asoc->hbinterval;
670
671 /* Set the path max_retrans. */
672 peer->pathmaxrxt = asoc->pathmaxrxt;
673
Neil Horman5aa93bc2012-07-21 07:56:07 +0000674 /* And the partial failure retrnas threshold */
675 peer->pf_retrans = asoc->pf_retrans;
676
Frank Filz52ccb8e2005-12-22 11:36:46 -0800677 /* Initialize the peer's SACK delay timeout based on the
678 * association configured value.
679 */
680 peer->sackdelay = asoc->sackdelay;
Wei Yongjund364d922008-05-09 15:13:26 -0700681 peer->sackfreq = asoc->sackfreq;
Frank Filz52ccb8e2005-12-22 11:36:46 -0800682
683 /* Enable/disable heartbeat, SACK delay, and path MTU discovery
684 * based on association setting.
685 */
686 peer->param_flags = asoc->param_flags;
687
Vlad Yasevich8da645e2009-09-04 18:21:01 -0400688 sctp_transport_route(peer, NULL, sp);
689
Linus Torvalds1da177e2005-04-16 15:20:36 -0700690 /* Initialize the pmtu of the transport. */
Vlad Yasevich8da645e2009-09-04 18:21:01 -0400691 if (peer->param_flags & SPP_PMTUD_DISABLE) {
692 if (asoc->pathmtu)
693 peer->pathmtu = asoc->pathmtu;
694 else
695 peer->pathmtu = SCTP_DEFAULT_MAXSEGMENT;
696 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700697
698 /* If this is the first transport addr on this association,
699 * initialize the association PMTU to the peer's PMTU.
700 * If not and the current association PMTU is higher than the new
701 * peer's PMTU, reset the association PMTU to the new peer's PMTU.
702 */
Frank Filz52ccb8e2005-12-22 11:36:46 -0800703 if (asoc->pathmtu)
704 asoc->pathmtu = min_t(int, peer->pathmtu, asoc->pathmtu);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700705 else
Frank Filz52ccb8e2005-12-22 11:36:46 -0800706 asoc->pathmtu = peer->pathmtu;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700707
Daniel Borkmannbb333812013-06-28 19:49:40 +0200708 pr_debug("%s: association:%p PMTU set to %d\n", __func__, asoc,
709 asoc->pathmtu);
710
Florian Westphal6d0ccba2008-07-18 23:04:39 -0700711 peer->pmtu_pending = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700712
Vlad Yasevichf68b2e02009-09-04 18:21:00 -0400713 asoc->frag_point = sctp_frag_point(asoc, asoc->pathmtu);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700714
715 /* The asoc->peer.port might not be meaningful yet, but
716 * initialize the packet structure anyway.
717 */
718 sctp_packet_init(&peer->packet, peer, asoc->base.bind_addr.port,
719 asoc->peer.port);
720
721 /* 7.2.1 Slow-Start
722 *
723 * o The initial cwnd before DATA transmission or after a sufficiently
724 * long idle period MUST be set to
725 * min(4*MTU, max(2*MTU, 4380 bytes))
726 *
727 * o The initial value of ssthresh MAY be arbitrarily high
728 * (for example, implementations MAY use the size of the
729 * receiver advertised window).
730 */
Frank Filz52ccb8e2005-12-22 11:36:46 -0800731 peer->cwnd = min(4*asoc->pathmtu, max_t(__u32, 2*asoc->pathmtu, 4380));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700732
733 /* At this point, we may not have the receiver's advertised window,
734 * so initialize ssthresh to the default value and it will be set
735 * later when we process the INIT.
736 */
737 peer->ssthresh = SCTP_DEFAULT_MAXWINDOW;
738
739 peer->partial_bytes_acked = 0;
740 peer->flight_size = 0;
Vlad Yasevich46d5a802009-11-23 15:54:00 -0500741 peer->burst_limited = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700742
Linus Torvalds1da177e2005-04-16 15:20:36 -0700743 /* Set the transport's RTO.initial value */
744 peer->rto = asoc->rto_initial;
Michele Baldessari196d6752012-12-01 04:49:42 +0000745 sctp_max_rto(asoc, peer);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700746
Frank Filz3f7a87d2005-06-20 13:14:57 -0700747 /* Set the peer's active state. */
748 peer->state = peer_state;
749
Linus Torvalds1da177e2005-04-16 15:20:36 -0700750 /* Attach the remote transport to our asoc. */
Thomas Graf45122ca262012-12-06 09:25:05 +0000751 list_add_tail_rcu(&peer->transports, &asoc->peer.transport_addr_list);
Frank Filz3f7a87d2005-06-20 13:14:57 -0700752 asoc->peer.transport_count++;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700753
754 /* If we do not yet have a primary path, set one. */
755 if (!asoc->peer.primary_path) {
756 sctp_assoc_set_primary(asoc, peer);
757 asoc->peer.retran_path = peer;
758 }
759
Vlad Yasevichfbdf5012010-04-30 22:39:26 -0400760 if (asoc->peer.active_path == asoc->peer.retran_path &&
761 peer->state != SCTP_UNCONFIRMED) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700762 asoc->peer.retran_path = peer;
Frank Filz3f7a87d2005-06-20 13:14:57 -0700763 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700764
765 return peer;
766}
767
768/* Delete a transport address from an association. */
769void sctp_assoc_del_peer(struct sctp_association *asoc,
770 const union sctp_addr *addr)
771{
772 struct list_head *pos;
773 struct list_head *temp;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700774 struct sctp_transport *transport;
775
776 list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
777 transport = list_entry(pos, struct sctp_transport, transports);
778 if (sctp_cmp_addr_exact(addr, &transport->ipaddr)) {
Frank Filz3f7a87d2005-06-20 13:14:57 -0700779 /* Do book keeping for removing the peer and free it. */
780 sctp_assoc_rm_peer(asoc, transport);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700781 break;
782 }
783 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700784}
785
786/* Lookup a transport by address. */
787struct sctp_transport *sctp_assoc_lookup_paddr(
788 const struct sctp_association *asoc,
789 const union sctp_addr *address)
790{
791 struct sctp_transport *t;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700792
793 /* Cycle through all transports searching for a peer address. */
794
Robert P. J. Day9dbc15f2008-04-12 18:54:24 -0700795 list_for_each_entry(t, &asoc->peer.transport_addr_list,
796 transports) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700797 if (sctp_cmp_addr_exact(address, &t->ipaddr))
798 return t;
799 }
800
801 return NULL;
802}
803
Vlad Yasevich42e30bf2007-12-20 14:08:56 -0800804/* Remove all transports except a give one */
805void sctp_assoc_del_nonprimary_peers(struct sctp_association *asoc,
806 struct sctp_transport *primary)
807{
808 struct sctp_transport *temp;
809 struct sctp_transport *t;
810
811 list_for_each_entry_safe(t, temp, &asoc->peer.transport_addr_list,
812 transports) {
813 /* if the current transport is not the primary one, delete it */
814 if (t != primary)
815 sctp_assoc_rm_peer(asoc, t);
816 }
Vlad Yasevich42e30bf2007-12-20 14:08:56 -0800817}
818
Linus Torvalds1da177e2005-04-16 15:20:36 -0700819/* Engage in transport control operations.
820 * Mark the transport up or down and send a notification to the user.
821 * Select and update the new active and retran paths.
822 */
823void sctp_assoc_control_transport(struct sctp_association *asoc,
824 struct sctp_transport *transport,
825 sctp_transport_cmd_t command,
826 sctp_sn_error_t error)
827{
828 struct sctp_transport *t = NULL;
829 struct sctp_transport *first;
830 struct sctp_transport *second;
831 struct sctp_ulpevent *event;
Al Viro0906e202006-11-20 17:03:01 -0800832 struct sockaddr_storage addr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700833 int spc_state = 0;
Neil Horman5aa93bc2012-07-21 07:56:07 +0000834 bool ulp_notify = true;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700835
836 /* Record the transition on the transport. */
837 switch (command) {
838 case SCTP_TRANSPORT_UP:
Vlad Yasevich1ae4114d2007-03-23 11:32:26 -0700839 /* If we are moving from UNCONFIRMED state due
840 * to heartbeat success, report the SCTP_ADDR_CONFIRMED
841 * state to the user, otherwise report SCTP_ADDR_AVAILABLE.
842 */
843 if (SCTP_UNCONFIRMED == transport->state &&
844 SCTP_HEARTBEAT_SUCCESS == error)
845 spc_state = SCTP_ADDR_CONFIRMED;
846 else
847 spc_state = SCTP_ADDR_AVAILABLE;
Neil Horman5aa93bc2012-07-21 07:56:07 +0000848 /* Don't inform ULP about transition from PF to
849 * active state and set cwnd to 1, see SCTP
850 * Quick failover draft section 5.1, point 5
851 */
852 if (transport->state == SCTP_PF) {
853 ulp_notify = false;
854 transport->cwnd = 1;
855 }
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
Neil Horman5aa93bc2012-07-21 07:56:07 +0000874 case SCTP_TRANSPORT_PF:
875 transport->state = SCTP_PF;
876 ulp_notify = false;
877 break;
878
Linus Torvalds1da177e2005-04-16 15:20:36 -0700879 default:
880 return;
Stephen Hemminger3ff50b72007-04-20 17:09:22 -0700881 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700882
883 /* Generate and send a SCTP_PEER_ADDR_CHANGE notification to the
884 * user.
885 */
Neil Horman5aa93bc2012-07-21 07:56:07 +0000886 if (ulp_notify) {
887 memset(&addr, 0, sizeof(struct sockaddr_storage));
888 memcpy(&addr, &transport->ipaddr,
889 transport->af_specific->sockaddr_len);
890 event = sctp_ulpevent_make_peer_addr_change(asoc, &addr,
891 0, spc_state, error, GFP_ATOMIC);
892 if (event)
893 sctp_ulpq_tail_event(&asoc->ulpq, event);
894 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700895
896 /* Select new active and retran paths. */
897
898 /* Look for the two most recently used active transports.
899 *
900 * This code produces the wrong ordering whenever jiffies
901 * rolls over, but we still get usable transports, so we don't
902 * worry about it.
903 */
904 first = NULL; second = NULL;
905
Robert P. J. Day9dbc15f2008-04-12 18:54:24 -0700906 list_for_each_entry(t, &asoc->peer.transport_addr_list,
907 transports) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700908
Sridhar Samudralaad8fec12006-07-21 14:48:50 -0700909 if ((t->state == SCTP_INACTIVE) ||
Neil Horman5aa93bc2012-07-21 07:56:07 +0000910 (t->state == SCTP_UNCONFIRMED) ||
911 (t->state == SCTP_PF))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700912 continue;
913 if (!first || t->last_time_heard > first->last_time_heard) {
914 second = first;
915 first = t;
916 }
917 if (!second || t->last_time_heard > second->last_time_heard)
918 second = t;
919 }
920
921 /* RFC 2960 6.4 Multi-Homed SCTP Endpoints
922 *
923 * By default, an endpoint should always transmit to the
924 * primary path, unless the SCTP user explicitly specifies the
925 * destination transport address (and possibly source
926 * transport address) to use.
927 *
928 * [If the primary is active but not most recent, bump the most
929 * recently used transport.]
930 */
Sridhar Samudralaad8fec12006-07-21 14:48:50 -0700931 if (((asoc->peer.primary_path->state == SCTP_ACTIVE) ||
932 (asoc->peer.primary_path->state == SCTP_UNKNOWN)) &&
Linus Torvalds1da177e2005-04-16 15:20:36 -0700933 first != asoc->peer.primary_path) {
934 second = first;
935 first = asoc->peer.primary_path;
936 }
937
938 /* If we failed to find a usable transport, just camp on the
939 * primary, even if it is inactive.
940 */
941 if (!first) {
942 first = asoc->peer.primary_path;
943 second = asoc->peer.primary_path;
944 }
945
946 /* Set the active and retran transports. */
947 asoc->peer.active_path = first;
948 asoc->peer.retran_path = second;
949}
950
951/* Hold a reference to an association. */
952void sctp_association_hold(struct sctp_association *asoc)
953{
954 atomic_inc(&asoc->base.refcnt);
955}
956
957/* Release a reference to an association and cleanup
958 * if there are no more references.
959 */
960void sctp_association_put(struct sctp_association *asoc)
961{
962 if (atomic_dec_and_test(&asoc->base.refcnt))
963 sctp_association_destroy(asoc);
964}
965
966/* Allocate the next TSN, Transmission Sequence Number, for the given
967 * association.
968 */
969__u32 sctp_association_get_next_tsn(struct sctp_association *asoc)
970{
971 /* From Section 1.6 Serial Number Arithmetic:
972 * Transmission Sequence Numbers wrap around when they reach
973 * 2**32 - 1. That is, the next TSN a DATA chunk MUST use
974 * after transmitting TSN = 2*32 - 1 is TSN = 0.
975 */
976 __u32 retval = asoc->next_tsn;
977 asoc->next_tsn++;
978 asoc->unack_data++;
979
980 return retval;
981}
982
983/* Compare two addresses to see if they match. Wildcard addresses
984 * only match themselves.
985 */
986int sctp_cmp_addr_exact(const union sctp_addr *ss1,
987 const union sctp_addr *ss2)
988{
989 struct sctp_af *af;
990
991 af = sctp_get_af_specific(ss1->sa.sa_family);
992 if (unlikely(!af))
993 return 0;
994
995 return af->cmp_addr(ss1, ss2);
996}
997
998/* Return an ecne chunk to get prepended to a packet.
999 * Note: We are sly and return a shared, prealloced chunk. FIXME:
1000 * No we don't, but we could/should.
1001 */
1002struct sctp_chunk *sctp_get_ecne_prepend(struct sctp_association *asoc)
1003{
1004 struct sctp_chunk *chunk;
1005
1006 /* Send ECNE if needed.
1007 * Not being able to allocate a chunk here is not deadly.
1008 */
1009 if (asoc->need_ecne)
1010 chunk = sctp_make_ecne(asoc, asoc->last_ecne_tsn);
1011 else
1012 chunk = NULL;
1013
1014 return chunk;
1015}
1016
1017/*
1018 * Find which transport this TSN was sent on.
1019 */
1020struct sctp_transport *sctp_assoc_lookup_tsn(struct sctp_association *asoc,
1021 __u32 tsn)
1022{
1023 struct sctp_transport *active;
1024 struct sctp_transport *match;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001025 struct sctp_transport *transport;
1026 struct sctp_chunk *chunk;
Al Virodbc16db2006-11-20 17:01:42 -08001027 __be32 key = htonl(tsn);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001028
1029 match = NULL;
1030
1031 /*
1032 * FIXME: In general, find a more efficient data structure for
1033 * searching.
1034 */
1035
1036 /*
1037 * The general strategy is to search each transport's transmitted
1038 * list. Return which transport this TSN lives on.
1039 *
1040 * Let's be hopeful and check the active_path first.
1041 * Another optimization would be to know if there is only one
1042 * outbound path and not have to look for the TSN at all.
1043 *
1044 */
1045
1046 active = asoc->peer.active_path;
1047
Robert P. J. Day9dbc15f2008-04-12 18:54:24 -07001048 list_for_each_entry(chunk, &active->transmitted,
1049 transmitted_list) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001050
1051 if (key == chunk->subh.data_hdr->tsn) {
1052 match = active;
1053 goto out;
1054 }
1055 }
1056
1057 /* If not found, go search all the other transports. */
Robert P. J. Day9dbc15f2008-04-12 18:54:24 -07001058 list_for_each_entry(transport, &asoc->peer.transport_addr_list,
1059 transports) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001060
1061 if (transport == active)
Xufeng Zhang2317f442013-03-07 21:39:37 +00001062 continue;
Robert P. J. Day9dbc15f2008-04-12 18:54:24 -07001063 list_for_each_entry(chunk, &transport->transmitted,
1064 transmitted_list) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001065 if (key == chunk->subh.data_hdr->tsn) {
1066 match = transport;
1067 goto out;
1068 }
1069 }
1070 }
1071out:
1072 return match;
1073}
1074
1075/* Is this the association we are looking for? */
1076struct sctp_transport *sctp_assoc_is_match(struct sctp_association *asoc,
Eric W. Biederman4110cc22012-08-06 08:41:13 +00001077 struct net *net,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001078 const union sctp_addr *laddr,
1079 const union sctp_addr *paddr)
1080{
1081 struct sctp_transport *transport;
1082
Al Viroe2fcced2006-11-20 17:08:41 -08001083 if ((htons(asoc->base.bind_addr.port) == laddr->v4.sin_port) &&
Eric W. Biederman4110cc22012-08-06 08:41:13 +00001084 (htons(asoc->peer.port) == paddr->v4.sin_port) &&
1085 net_eq(sock_net(asoc->base.sk), net)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001086 transport = sctp_assoc_lookup_paddr(asoc, paddr);
1087 if (!transport)
1088 goto out;
1089
1090 if (sctp_bind_addr_match(&asoc->base.bind_addr, laddr,
1091 sctp_sk(asoc->base.sk)))
1092 goto out;
1093 }
1094 transport = NULL;
1095
1096out:
Linus Torvalds1da177e2005-04-16 15:20:36 -07001097 return transport;
1098}
1099
1100/* Do delayed input processing. This is scheduled by sctp_rcv(). */
David Howellsc4028952006-11-22 14:57:56 +00001101static void sctp_assoc_bh_rcv(struct work_struct *work)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001102{
David Howellsc4028952006-11-22 14:57:56 +00001103 struct sctp_association *asoc =
1104 container_of(work, struct sctp_association,
1105 base.inqueue.immediate);
Eric W. Biederman55e26eb2012-08-07 07:25:24 +00001106 struct net *net = sock_net(asoc->base.sk);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001107 struct sctp_endpoint *ep;
1108 struct sctp_chunk *chunk;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001109 struct sctp_inq *inqueue;
1110 int state;
1111 sctp_subtype_t subtype;
1112 int error = 0;
1113
1114 /* The association should be held so we should be safe. */
1115 ep = asoc->ep;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001116
1117 inqueue = &asoc->base.inqueue;
1118 sctp_association_hold(asoc);
1119 while (NULL != (chunk = sctp_inq_pop(inqueue))) {
1120 state = asoc->state;
1121 subtype = SCTP_ST_CHUNK(chunk->chunk_hdr->type);
1122
Vlad Yasevichbbd0d592007-10-03 17:51:34 -07001123 /* SCTP-AUTH, Section 6.3:
1124 * The receiver has a list of chunk types which it expects
1125 * to be received only after an AUTH-chunk. This list has
1126 * been sent to the peer during the association setup. It
1127 * MUST silently discard these chunks if they are not placed
1128 * after an AUTH chunk in the packet.
1129 */
1130 if (sctp_auth_recv_cid(subtype.chunk, asoc) && !chunk->auth)
1131 continue;
1132
Linus Torvalds1da177e2005-04-16 15:20:36 -07001133 /* Remember where the last DATA chunk came from so we
1134 * know where to send the SACK.
1135 */
1136 if (sctp_chunk_is_data(chunk))
1137 asoc->peer.last_data_from = chunk->transport;
Michele Baldessari196d6752012-12-01 04:49:42 +00001138 else {
Eric W. Biederman55e26eb2012-08-07 07:25:24 +00001139 SCTP_INC_STATS(net, SCTP_MIB_INCTRLCHUNKS);
Michele Baldessari196d6752012-12-01 04:49:42 +00001140 asoc->stats.ictrlchunks++;
1141 if (chunk->chunk_hdr->type == SCTP_CID_SACK)
1142 asoc->stats.isacks++;
1143 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001144
1145 if (chunk->transport)
1146 chunk->transport->last_time_heard = jiffies;
1147
1148 /* Run through the state machine. */
Eric W. Biederman55e26eb2012-08-07 07:25:24 +00001149 error = sctp_do_sm(net, SCTP_EVENT_T_CHUNK, subtype,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001150 state, ep, asoc, chunk, GFP_ATOMIC);
1151
1152 /* Check to see if the association is freed in response to
1153 * the incoming chunk. If so, get out of the while loop.
1154 */
1155 if (asoc->base.dead)
1156 break;
1157
1158 /* If there is an error on chunk, discard this packet. */
1159 if (error && chunk)
1160 chunk->pdiscard = 1;
1161 }
1162 sctp_association_put(asoc);
1163}
1164
1165/* This routine moves an association from its old sk to a new sk. */
1166void sctp_assoc_migrate(struct sctp_association *assoc, struct sock *newsk)
1167{
1168 struct sctp_sock *newsp = sctp_sk(newsk);
1169 struct sock *oldsk = assoc->base.sk;
1170
1171 /* Delete the association from the old endpoint's list of
1172 * associations.
1173 */
1174 list_del_init(&assoc->asocs);
1175
1176 /* Decrement the backlog value for a TCP-style socket. */
1177 if (sctp_style(oldsk, TCP))
1178 oldsk->sk_ack_backlog--;
1179
1180 /* Release references to the old endpoint and the sock. */
1181 sctp_endpoint_put(assoc->ep);
1182 sock_put(assoc->base.sk);
1183
1184 /* Get a reference to the new endpoint. */
1185 assoc->ep = newsp->ep;
1186 sctp_endpoint_hold(assoc->ep);
1187
1188 /* Get a reference to the new sock. */
1189 assoc->base.sk = newsk;
1190 sock_hold(assoc->base.sk);
1191
1192 /* Add the association to the new endpoint's list of associations. */
1193 sctp_endpoint_add_asoc(newsp->ep, assoc);
1194}
1195
1196/* Update an association (possibly from unexpected COOKIE-ECHO processing). */
1197void sctp_assoc_update(struct sctp_association *asoc,
1198 struct sctp_association *new)
1199{
1200 struct sctp_transport *trans;
1201 struct list_head *pos, *temp;
1202
1203 /* Copy in new parameters of peer. */
1204 asoc->c = new->c;
1205 asoc->peer.rwnd = new->peer.rwnd;
1206 asoc->peer.sack_needed = new->peer.sack_needed;
1207 asoc->peer.i = new->peer.i;
Vlad Yasevich8e1ee182008-10-08 14:18:39 -07001208 sctp_tsnmap_init(&asoc->peer.tsn_map, SCTP_TSN_MAP_INITIAL,
1209 asoc->peer.i.initial_tsn, GFP_ATOMIC);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001210
1211 /* Remove any peer addresses not present in the new association. */
1212 list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
1213 trans = list_entry(pos, struct sctp_transport, transports);
Vlad Yasevich0c427492010-04-28 08:47:19 +00001214 if (!sctp_assoc_lookup_paddr(new, &trans->ipaddr)) {
1215 sctp_assoc_rm_peer(asoc, trans);
1216 continue;
1217 }
Vlad Yasevich749bf922007-03-19 17:02:30 -07001218
1219 if (asoc->state >= SCTP_STATE_ESTABLISHED)
1220 sctp_transport_reset(trans);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001221 }
1222
1223 /* If the case is A (association restart), use
1224 * initial_tsn as next_tsn. If the case is B, use
1225 * current next_tsn in case data sent to peer
1226 * has been discarded and needs retransmission.
1227 */
1228 if (asoc->state >= SCTP_STATE_ESTABLISHED) {
1229 asoc->next_tsn = new->next_tsn;
1230 asoc->ctsn_ack_point = new->ctsn_ack_point;
1231 asoc->adv_peer_ack_point = new->adv_peer_ack_point;
1232
1233 /* Reinitialize SSN for both local streams
1234 * and peer's streams.
1235 */
1236 sctp_ssnmap_clear(asoc->ssnmap);
1237
Vlad Yasevich0b58a812007-03-19 17:01:17 -07001238 /* Flush the ULP reassembly and ordered queue.
1239 * Any data there will now be stale and will
1240 * cause problems.
1241 */
1242 sctp_ulpq_flush(&asoc->ulpq);
1243
Vlad Yasevich749bf922007-03-19 17:02:30 -07001244 /* reset the overall association error count so
1245 * that the restarted association doesn't get torn
1246 * down on the next retransmission timer.
1247 */
1248 asoc->overall_error_count = 0;
1249
Linus Torvalds1da177e2005-04-16 15:20:36 -07001250 } else {
1251 /* Add any peer addresses from the new association. */
Robert P. J. Day9dbc15f2008-04-12 18:54:24 -07001252 list_for_each_entry(trans, &new->peer.transport_addr_list,
1253 transports) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001254 if (!sctp_assoc_lookup_paddr(asoc, &trans->ipaddr))
1255 sctp_assoc_add_peer(asoc, &trans->ipaddr,
Sridhar Samudralaad8fec12006-07-21 14:48:50 -07001256 GFP_ATOMIC, trans->state);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001257 }
1258
1259 asoc->ctsn_ack_point = asoc->next_tsn - 1;
1260 asoc->adv_peer_ack_point = asoc->ctsn_ack_point;
1261 if (!asoc->ssnmap) {
1262 /* Move the ssnmap. */
1263 asoc->ssnmap = new->ssnmap;
1264 new->ssnmap = NULL;
1265 }
Vlad Yasevich07d93962007-05-04 13:55:27 -07001266
1267 if (!asoc->assoc_id) {
1268 /* get a new association id since we don't have one
1269 * yet.
1270 */
1271 sctp_assoc_set_id(asoc, GFP_ATOMIC);
1272 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001273 }
Vlad Yasevicha29a5bd2007-09-16 19:31:35 -07001274
Vlad Yasevich730fc3d2007-09-16 19:32:11 -07001275 /* SCTP-AUTH: Save the peer parameters from the new assocaitions
1276 * and also move the association shared keys over
1277 */
1278 kfree(asoc->peer.peer_random);
1279 asoc->peer.peer_random = new->peer.peer_random;
1280 new->peer.peer_random = NULL;
1281
1282 kfree(asoc->peer.peer_chunks);
1283 asoc->peer.peer_chunks = new->peer.peer_chunks;
1284 new->peer.peer_chunks = NULL;
1285
1286 kfree(asoc->peer.peer_hmacs);
1287 asoc->peer.peer_hmacs = new->peer.peer_hmacs;
1288 new->peer.peer_hmacs = NULL;
1289
1290 sctp_auth_key_put(asoc->asoc_shared_key);
1291 sctp_auth_asoc_init_active_key(asoc, GFP_ATOMIC);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001292}
1293
1294/* Update the retran path for sending a retransmitted packet.
1295 * Round-robin through the active transports, else round-robin
1296 * through the inactive transports as this is the next best thing
1297 * we can try.
1298 */
1299void sctp_assoc_update_retran_path(struct sctp_association *asoc)
1300{
1301 struct sctp_transport *t, *next;
1302 struct list_head *head = &asoc->peer.transport_addr_list;
1303 struct list_head *pos;
1304
Gui Jianfeng4141ddc2008-06-04 12:37:33 -07001305 if (asoc->peer.transport_count == 1)
1306 return;
1307
Linus Torvalds1da177e2005-04-16 15:20:36 -07001308 /* Find the next transport in a round-robin fashion. */
1309 t = asoc->peer.retran_path;
1310 pos = &t->transports;
1311 next = NULL;
1312
1313 while (1) {
1314 /* Skip the head. */
1315 if (pos->next == head)
1316 pos = head->next;
1317 else
1318 pos = pos->next;
1319
1320 t = list_entry(pos, struct sctp_transport, transports);
1321
Gui Jianfeng4141ddc2008-06-04 12:37:33 -07001322 /* We have exhausted the list, but didn't find any
1323 * other active transports. If so, use the next
1324 * transport.
1325 */
1326 if (t == asoc->peer.retran_path) {
1327 t = next;
1328 break;
1329 }
1330
Linus Torvalds1da177e2005-04-16 15:20:36 -07001331 /* Try to find an active transport. */
1332
Sridhar Samudralaad8fec12006-07-21 14:48:50 -07001333 if ((t->state == SCTP_ACTIVE) ||
1334 (t->state == SCTP_UNKNOWN)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001335 break;
1336 } else {
1337 /* Keep track of the next transport in case
1338 * we don't find any active transport.
1339 */
Vlad Yasevichfbdf5012010-04-30 22:39:26 -04001340 if (t->state != SCTP_UNCONFIRMED && !next)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001341 next = t;
1342 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001343 }
1344
Vlad Yasevichd598b162010-04-30 22:41:09 -04001345 if (t)
1346 asoc->peer.retran_path = t;
Vlad Yasevich25f7bf72011-04-12 15:20:48 +00001347 else
1348 t = asoc->peer.retran_path;
Frank Filz3f7a87d2005-06-20 13:14:57 -07001349
Daniel Borkmannbb333812013-06-28 19:49:40 +02001350 pr_debug("%s: association:%p addr:%pISpc\n", __func__, asoc,
1351 &t->ipaddr.sa);
Frank Filz3f7a87d2005-06-20 13:14:57 -07001352}
1353
Wei Yongjun9919b452009-05-12 21:52:51 +08001354/* Choose the transport for sending retransmit packet. */
1355struct sctp_transport *sctp_assoc_choose_alter_transport(
1356 struct sctp_association *asoc, struct sctp_transport *last_sent_to)
Frank Filz3f7a87d2005-06-20 13:14:57 -07001357{
Wei Yongjun9919b452009-05-12 21:52:51 +08001358 /* If this is the first time packet is sent, use the active path,
1359 * else use the retran path. If the last packet was sent over the
Frank Filz3f7a87d2005-06-20 13:14:57 -07001360 * retran path, update the retran path and use it.
1361 */
Wei Yongjun9919b452009-05-12 21:52:51 +08001362 if (!last_sent_to)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001363 return asoc->peer.active_path;
1364 else {
Wei Yongjun9919b452009-05-12 21:52:51 +08001365 if (last_sent_to == asoc->peer.retran_path)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001366 sctp_assoc_update_retran_path(asoc);
1367 return asoc->peer.retran_path;
1368 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001369}
1370
1371/* Update the association's pmtu and frag_point by going through all the
1372 * transports. This routine is called when a transport's PMTU has changed.
1373 */
David S. Miller02f3d4c2012-07-16 03:57:14 -07001374void sctp_assoc_sync_pmtu(struct sock *sk, struct sctp_association *asoc)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001375{
1376 struct sctp_transport *t;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001377 __u32 pmtu = 0;
1378
1379 if (!asoc)
1380 return;
1381
1382 /* Get the lowest pmtu of all the transports. */
Robert P. J. Day9dbc15f2008-04-12 18:54:24 -07001383 list_for_each_entry(t, &asoc->peer.transport_addr_list,
1384 transports) {
Vlad Yasevich8a479492007-06-07 14:21:05 -04001385 if (t->pmtu_pending && t->dst) {
David S. Miller02f3d4c2012-07-16 03:57:14 -07001386 sctp_transport_update_pmtu(sk, t, dst_mtu(t->dst));
Vlad Yasevich8a479492007-06-07 14:21:05 -04001387 t->pmtu_pending = 0;
1388 }
Frank Filz52ccb8e2005-12-22 11:36:46 -08001389 if (!pmtu || (t->pathmtu < pmtu))
1390 pmtu = t->pathmtu;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001391 }
1392
1393 if (pmtu) {
Frank Filz52ccb8e2005-12-22 11:36:46 -08001394 asoc->pathmtu = pmtu;
Vlad Yasevichf68b2e02009-09-04 18:21:00 -04001395 asoc->frag_point = sctp_frag_point(asoc, pmtu);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001396 }
1397
Daniel Borkmannbb333812013-06-28 19:49:40 +02001398 pr_debug("%s: asoc:%p, pmtu:%d, frag_point:%d\n", __func__, asoc,
1399 asoc->pathmtu, asoc->frag_point);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001400}
1401
1402/* Should we send a SACK to update our peer? */
1403static inline int sctp_peer_needs_update(struct sctp_association *asoc)
1404{
Eric W. Biedermane1fc3b12012-08-07 07:29:57 +00001405 struct net *net = sock_net(asoc->base.sk);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001406 switch (asoc->state) {
1407 case SCTP_STATE_ESTABLISHED:
1408 case SCTP_STATE_SHUTDOWN_PENDING:
1409 case SCTP_STATE_SHUTDOWN_RECEIVED:
1410 case SCTP_STATE_SHUTDOWN_SENT:
1411 if ((asoc->rwnd > asoc->a_rwnd) &&
Vlad Yasevich90f2f532009-11-23 15:53:57 -05001412 ((asoc->rwnd - asoc->a_rwnd) >= max_t(__u32,
Eric W. Biedermane1fc3b12012-08-07 07:29:57 +00001413 (asoc->base.sk->sk_rcvbuf >> net->sctp.rwnd_upd_shift),
Vlad Yasevich90f2f532009-11-23 15:53:57 -05001414 asoc->pathmtu)))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001415 return 1;
1416 break;
1417 default:
1418 break;
1419 }
1420 return 0;
1421}
1422
1423/* Increase asoc's rwnd by len and send any window update SACK if needed. */
Eric Dumazet95c96172012-04-15 05:58:06 +00001424void sctp_assoc_rwnd_increase(struct sctp_association *asoc, unsigned int len)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001425{
1426 struct sctp_chunk *sack;
1427 struct timer_list *timer;
1428
1429 if (asoc->rwnd_over) {
1430 if (asoc->rwnd_over >= len) {
1431 asoc->rwnd_over -= len;
1432 } else {
1433 asoc->rwnd += (len - asoc->rwnd_over);
1434 asoc->rwnd_over = 0;
1435 }
1436 } else {
1437 asoc->rwnd += len;
1438 }
1439
Vlad Yasevich4d3c46e2009-09-04 18:20:59 -04001440 /* If we had window pressure, start recovering it
1441 * once our rwnd had reached the accumulated pressure
1442 * threshold. The idea is to recover slowly, but up
1443 * to the initial advertised window.
1444 */
1445 if (asoc->rwnd_press && asoc->rwnd >= asoc->rwnd_press) {
1446 int change = min(asoc->pathmtu, asoc->rwnd_press);
1447 asoc->rwnd += change;
1448 asoc->rwnd_press -= change;
1449 }
1450
Daniel Borkmannbb333812013-06-28 19:49:40 +02001451 pr_debug("%s: asoc:%p rwnd increased by %d to (%u, %u) - %u\n",
1452 __func__, asoc, len, asoc->rwnd, asoc->rwnd_over,
1453 asoc->a_rwnd);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001454
1455 /* Send a window update SACK if the rwnd has increased by at least the
1456 * minimum of the association's PMTU and half of the receive buffer.
1457 * The algorithm used is similar to the one described in
1458 * Section 4.2.3.3 of RFC 1122.
1459 */
1460 if (sctp_peer_needs_update(asoc)) {
1461 asoc->a_rwnd = asoc->rwnd;
Daniel Borkmannbb333812013-06-28 19:49:40 +02001462
1463 pr_debug("%s: sending window update SACK- asoc:%p rwnd:%u "
1464 "a_rwnd:%u\n", __func__, asoc, asoc->rwnd,
1465 asoc->a_rwnd);
1466
Linus Torvalds1da177e2005-04-16 15:20:36 -07001467 sack = sctp_make_sack(asoc);
1468 if (!sack)
1469 return;
1470
1471 asoc->peer.sack_needed = 0;
1472
1473 sctp_outq_tail(&asoc->outqueue, sack);
1474
1475 /* Stop the SACK timer. */
1476 timer = &asoc->timers[SCTP_EVENT_TIMEOUT_SACK];
Ying Xue25cc4ae2013-02-03 20:32:57 +00001477 if (del_timer(timer))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001478 sctp_association_put(asoc);
1479 }
1480}
1481
1482/* Decrease asoc's rwnd by len. */
Eric Dumazet95c96172012-04-15 05:58:06 +00001483void sctp_assoc_rwnd_decrease(struct sctp_association *asoc, unsigned int len)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001484{
Vlad Yasevich4d3c46e2009-09-04 18:20:59 -04001485 int rx_count;
1486 int over = 0;
1487
Daniel Borkmannbb333812013-06-28 19:49:40 +02001488 if (unlikely(!asoc->rwnd || asoc->rwnd_over))
1489 pr_debug("%s: association:%p has asoc->rwnd:%u, "
1490 "asoc->rwnd_over:%u!\n", __func__, asoc,
1491 asoc->rwnd, asoc->rwnd_over);
Vlad Yasevich4d3c46e2009-09-04 18:20:59 -04001492
1493 if (asoc->ep->rcvbuf_policy)
1494 rx_count = atomic_read(&asoc->rmem_alloc);
1495 else
1496 rx_count = atomic_read(&asoc->base.sk->sk_rmem_alloc);
1497
1498 /* If we've reached or overflowed our receive buffer, announce
1499 * a 0 rwnd if rwnd would still be positive. Store the
1500 * the pottential pressure overflow so that the window can be restored
1501 * back to original value.
1502 */
1503 if (rx_count >= asoc->base.sk->sk_rcvbuf)
1504 over = 1;
1505
Linus Torvalds1da177e2005-04-16 15:20:36 -07001506 if (asoc->rwnd >= len) {
1507 asoc->rwnd -= len;
Vlad Yasevich4d3c46e2009-09-04 18:20:59 -04001508 if (over) {
Vlad Yasevich65883372010-04-30 22:41:10 -04001509 asoc->rwnd_press += asoc->rwnd;
Vlad Yasevich4d3c46e2009-09-04 18:20:59 -04001510 asoc->rwnd = 0;
1511 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001512 } else {
1513 asoc->rwnd_over = len - asoc->rwnd;
1514 asoc->rwnd = 0;
1515 }
Daniel Borkmannbb333812013-06-28 19:49:40 +02001516
1517 pr_debug("%s: asoc:%p rwnd decreased by %d to (%u, %u, %u)\n",
1518 __func__, asoc, len, asoc->rwnd, asoc->rwnd_over,
1519 asoc->rwnd_press);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001520}
1521
1522/* Build the bind address list for the association based on info from the
1523 * local endpoint and the remote peer.
1524 */
Alexey Dobriyan3182cd82005-07-11 20:57:47 -07001525int sctp_assoc_set_bind_addr_from_ep(struct sctp_association *asoc,
Vlad Yasevich409b95a2009-11-10 08:57:34 +00001526 sctp_scope_t scope, gfp_t gfp)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001527{
Linus Torvalds1da177e2005-04-16 15:20:36 -07001528 int flags;
1529
1530 /* Use scoping rules to determine the subset of addresses from
1531 * the endpoint.
1532 */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001533 flags = (PF_INET6 == asoc->base.sk->sk_family) ? SCTP_ADDR6_ALLOWED : 0;
1534 if (asoc->peer.ipv4_address)
1535 flags |= SCTP_ADDR4_PEERSUPP;
1536 if (asoc->peer.ipv6_address)
1537 flags |= SCTP_ADDR6_PEERSUPP;
1538
Eric W. Biederman4db67e82012-08-06 08:42:04 +00001539 return sctp_bind_addr_copy(sock_net(asoc->base.sk),
1540 &asoc->base.bind_addr,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001541 &asoc->ep->base.bind_addr,
1542 scope, gfp, flags);
1543}
1544
1545/* Build the association's bind address list from the cookie. */
1546int sctp_assoc_set_bind_addr_from_cookie(struct sctp_association *asoc,
Alexey Dobriyan3182cd82005-07-11 20:57:47 -07001547 struct sctp_cookie *cookie,
Al Virodd0fc662005-10-07 07:46:04 +01001548 gfp_t gfp)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001549{
1550 int var_size2 = ntohs(cookie->peer_init->chunk_hdr.length);
1551 int var_size3 = cookie->raw_addr_list_len;
1552 __u8 *raw = (__u8 *)cookie->peer_init + var_size2;
1553
1554 return sctp_raw_to_bind_addrs(&asoc->base.bind_addr, raw, var_size3,
1555 asoc->ep->base.bind_addr.port, gfp);
1556}
1557
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +09001558/* Lookup laddr in the bind address list of an association. */
1559int sctp_assoc_lookup_laddr(struct sctp_association *asoc,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001560 const union sctp_addr *laddr)
1561{
Vlad Yasevich559cf712007-09-16 16:03:28 -07001562 int found = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001563
Linus Torvalds1da177e2005-04-16 15:20:36 -07001564 if ((asoc->base.bind_addr.port == ntohs(laddr->v4.sin_port)) &&
1565 sctp_bind_addr_match(&asoc->base.bind_addr, laddr,
Vlad Yasevich559cf712007-09-16 16:03:28 -07001566 sctp_sk(asoc->base.sk)))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001567 found = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001568
Linus Torvalds1da177e2005-04-16 15:20:36 -07001569 return found;
1570}
Vlad Yasevich07d93962007-05-04 13:55:27 -07001571
1572/* Set an association id for a given association */
1573int sctp_assoc_set_id(struct sctp_association *asoc, gfp_t gfp)
1574{
Tejun Heo94960e82013-02-27 17:05:00 -08001575 bool preload = gfp & __GFP_WAIT;
1576 int ret;
Vlad Yasevichc6ba68a2009-06-01 12:41:15 -04001577
1578 /* If the id is already assigned, keep it. */
1579 if (asoc->assoc_id)
Tejun Heo94960e82013-02-27 17:05:00 -08001580 return 0;
Vlad Yasevich07d93962007-05-04 13:55:27 -07001581
Tejun Heo94960e82013-02-27 17:05:00 -08001582 if (preload)
1583 idr_preload(gfp);
Vlad Yasevich07d93962007-05-04 13:55:27 -07001584 spin_lock_bh(&sctp_assocs_id_lock);
Jeff Layton713e00a2013-04-29 16:21:22 -07001585 /* 0 is not a valid assoc_id, must be >= 1 */
1586 ret = idr_alloc_cyclic(&sctp_assocs_id, asoc, 1, 0, GFP_NOWAIT);
Vlad Yasevich07d93962007-05-04 13:55:27 -07001587 spin_unlock_bh(&sctp_assocs_id_lock);
Tejun Heo94960e82013-02-27 17:05:00 -08001588 if (preload)
1589 idr_preload_end();
1590 if (ret < 0)
1591 return ret;
Vlad Yasevich07d93962007-05-04 13:55:27 -07001592
Tejun Heo94960e82013-02-27 17:05:00 -08001593 asoc->assoc_id = (sctp_assoc_t)ret;
1594 return 0;
Vlad Yasevich07d93962007-05-04 13:55:27 -07001595}
Vlad Yasevicha08de642007-12-20 14:11:47 -08001596
Wei Yongjun8b4472c2011-05-24 21:48:02 +00001597/* Free the ASCONF queue */
1598static void sctp_assoc_free_asconf_queue(struct sctp_association *asoc)
1599{
1600 struct sctp_chunk *asconf;
1601 struct sctp_chunk *tmp;
1602
1603 list_for_each_entry_safe(asconf, tmp, &asoc->addip_chunk_list, list) {
1604 list_del_init(&asconf->list);
1605 sctp_chunk_free(asconf);
1606 }
1607}
1608
Vlad Yasevicha08de642007-12-20 14:11:47 -08001609/* Free asconf_ack cache */
1610static void sctp_assoc_free_asconf_acks(struct sctp_association *asoc)
1611{
1612 struct sctp_chunk *ack;
1613 struct sctp_chunk *tmp;
1614
1615 list_for_each_entry_safe(ack, tmp, &asoc->asconf_ack_list,
1616 transmitted_list) {
1617 list_del_init(&ack->transmitted_list);
1618 sctp_chunk_free(ack);
1619 }
1620}
1621
1622/* Clean up the ASCONF_ACK queue */
1623void sctp_assoc_clean_asconf_ack_cache(const struct sctp_association *asoc)
1624{
1625 struct sctp_chunk *ack;
1626 struct sctp_chunk *tmp;
1627
Lucas De Marchi25985ed2011-03-30 22:57:33 -03001628 /* We can remove all the entries from the queue up to
Vlad Yasevicha08de642007-12-20 14:11:47 -08001629 * the "Peer-Sequence-Number".
1630 */
1631 list_for_each_entry_safe(ack, tmp, &asoc->asconf_ack_list,
1632 transmitted_list) {
1633 if (ack->subh.addip_hdr->serial ==
1634 htonl(asoc->peer.addip_serial))
1635 break;
1636
1637 list_del_init(&ack->transmitted_list);
1638 sctp_chunk_free(ack);
1639 }
1640}
1641
1642/* Find the ASCONF_ACK whose serial number matches ASCONF */
1643struct sctp_chunk *sctp_assoc_lookup_asconf_ack(
1644 const struct sctp_association *asoc,
1645 __be32 serial)
1646{
Wei Yongjuna8699812008-02-05 23:35:04 +09001647 struct sctp_chunk *ack;
Vlad Yasevicha08de642007-12-20 14:11:47 -08001648
1649 /* Walk through the list of cached ASCONF-ACKs and find the
1650 * ack chunk whose serial number matches that of the request.
1651 */
1652 list_for_each_entry(ack, &asoc->asconf_ack_list, transmitted_list) {
1653 if (ack->subh.addip_hdr->serial == serial) {
1654 sctp_chunk_hold(ack);
Wei Yongjuna8699812008-02-05 23:35:04 +09001655 return ack;
Vlad Yasevicha08de642007-12-20 14:11:47 -08001656 }
1657 }
1658
Wei Yongjuna8699812008-02-05 23:35:04 +09001659 return NULL;
Vlad Yasevicha08de642007-12-20 14:11:47 -08001660}
Wei Yongjuna000c012011-05-29 23:23:36 +00001661
1662void sctp_asconf_queue_teardown(struct sctp_association *asoc)
1663{
1664 /* Free any cached ASCONF_ACK chunk. */
1665 sctp_assoc_free_asconf_acks(asoc);
1666
1667 /* Free the ASCONF queue. */
1668 sctp_assoc_free_asconf_queue(asoc);
1669
1670 /* Free any cached ASCONF chunk. */
1671 if (asoc->addip_last_asconf)
1672 sctp_chunk_free(asoc->addip_last_asconf);
1673}