blob: 72315137d7e7f20d5182291ef4b01102f030078b [file] [log] [blame]
Thomas Gleixner47505b82019-05-23 11:14:41 +02001// SPDX-License-Identifier: GPL-2.0-or-later
Vlad Yasevich60c778b2008-01-11 09:57:09 -05002/* SCTP kernel implementation
Linus Torvalds1da177e2005-04-16 15:20:36 -07003 * (C) Copyright IBM Corp. 2001, 2004
4 * Copyright (c) 1999-2000 Cisco, Inc.
5 * Copyright (c) 1999-2001 Motorola, Inc.
6 * Copyright (c) 2001 Intel Corp.
7 * Copyright (c) 2001 La Monte H.P. Yarroll
8 *
Vlad Yasevich60c778b2008-01-11 09:57:09 -05009 * This file is part of the SCTP kernel implementation
Linus Torvalds1da177e2005-04-16 15:20:36 -070010 *
11 * This module provides the abstraction for an SCTP association.
12 *
Linus Torvalds1da177e2005-04-16 15:20:36 -070013 * Please send any bug reports or fixes you make to the
14 * email address(es):
Daniel Borkmann91705c62013-07-23 14:51:47 +020015 * lksctp developers <linux-sctp@vger.kernel.org>
Linus Torvalds1da177e2005-04-16 15:20:36 -070016 *
Linus Torvalds1da177e2005-04-16 15:20:36 -070017 * Written or modified by:
18 * La Monte H.P. Yarroll <piggy@acm.org>
19 * Karl Knutson <karl@athena.chicago.il.us>
20 * Jon Grimm <jgrimm@us.ibm.com>
21 * Xingang Guo <xingang.guo@intel.com>
22 * Hui Huang <hui.huang@nokia.com>
23 * Sridhar Samudrala <sri@us.ibm.com>
24 * Daisy Chang <daisyc@us.ibm.com>
25 * Ryan Layer <rmlayer@us.ibm.com>
26 * Kevin Gao <kevin.gao@intel.com>
Linus Torvalds1da177e2005-04-16 15:20:36 -070027 */
28
Joe Perches145ce502010-08-24 13:21:08 +000029#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
30
Linus Torvalds1da177e2005-04-16 15:20:36 -070031#include <linux/types.h>
32#include <linux/fcntl.h>
33#include <linux/poll.h>
34#include <linux/init.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070035
36#include <linux/slab.h>
37#include <linux/in.h>
38#include <net/ipv6.h>
39#include <net/sctp/sctp.h>
40#include <net/sctp/sm.h>
41
42/* Forward declarations for internal functions. */
Daniel Borkmannb82e8f32014-06-11 18:19:29 +020043static void sctp_select_active_and_retran_path(struct sctp_association *asoc);
David Howellsc4028952006-11-22 14:57:56 +000044static void sctp_assoc_bh_rcv(struct work_struct *work);
Vlad Yasevicha08de642007-12-20 14:11:47 -080045static void sctp_assoc_free_asconf_acks(struct sctp_association *asoc);
Wei Yongjun8b4472c2011-05-24 21:48:02 +000046static void sctp_assoc_free_asconf_queue(struct sctp_association *asoc);
Linus Torvalds1da177e2005-04-16 15:20:36 -070047
Linus Torvalds1da177e2005-04-16 15:20:36 -070048/* 1st Level Abstractions. */
49
50/* Initialize a new association from provided memory. */
Xin Long1c662012017-08-05 19:59:54 +080051static struct sctp_association *sctp_association_init(
52 struct sctp_association *asoc,
53 const struct sctp_endpoint *ep,
54 const struct sock *sk,
55 enum sctp_scope scope, gfp_t gfp)
Linus Torvalds1da177e2005-04-16 15:20:36 -070056{
57 struct sctp_sock *sp;
Xin Long3c918702017-06-30 11:52:16 +080058 struct sctp_paramhdr *p;
Xin Long58194772017-03-20 18:00:28 +080059 int i;
Linus Torvalds1da177e2005-04-16 15:20:36 -070060
61 /* Retrieve the SCTP per socket area. */
62 sp = sctp_sk((struct sock *)sk);
63
Linus Torvalds1da177e2005-04-16 15:20:36 -070064 /* Discarding const is appropriate here. */
65 asoc->ep = (struct sctp_endpoint *)ep;
Linus Torvalds1da177e2005-04-16 15:20:36 -070066 asoc->base.sk = (struct sock *)sk;
Xin Long31243462019-11-23 11:56:49 +080067 asoc->base.net = sock_net(sk);
Daniel Borkmann2e0c9e72013-06-14 18:24:07 +020068
69 sctp_endpoint_hold(asoc->ep);
Linus Torvalds1da177e2005-04-16 15:20:36 -070070 sock_hold(asoc->base.sk);
71
72 /* Initialize the common base substructure. */
73 asoc->base.type = SCTP_EP_TYPE_ASSOCIATION;
74
75 /* Initialize the object handling fields. */
Reshetova, Elenac6384572017-07-04 15:53:28 +030076 refcount_set(&asoc->base.refcnt, 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -070077
78 /* Initialize the bind addr area. */
79 sctp_bind_addr_init(&asoc->base.bind_addr, ep->base.bind_addr.port);
Linus Torvalds1da177e2005-04-16 15:20:36 -070080
81 asoc->state = SCTP_STATE_CLOSED;
Daniel Borkmann52db8822013-06-25 18:17:27 +020082 asoc->cookie_life = ms_to_ktime(sp->assocparams.sasoc_cookie_life);
Vlad Yasevichf68b2e02009-09-04 18:21:00 -040083 asoc->user_frag = sp->user_frag;
Linus Torvalds1da177e2005-04-16 15:20:36 -070084
85 /* Set the association max_retrans and RTO values from the
86 * socket values.
87 */
88 asoc->max_retrans = sp->assocparams.sasoc_asocmaxrxt;
Xin Long8add5432019-01-28 15:08:29 +080089 asoc->pf_retrans = sp->pf_retrans;
Xin Long34515e92019-11-08 13:20:35 +080090 asoc->ps_retrans = sp->ps_retrans;
Xin Longaef587b2019-11-08 13:20:32 +080091 asoc->pf_expose = sp->pf_expose;
Neil Horman5aa93bc2012-07-21 07:56:07 +000092
Linus Torvalds1da177e2005-04-16 15:20:36 -070093 asoc->rto_initial = msecs_to_jiffies(sp->rtoinfo.srto_initial);
94 asoc->rto_max = msecs_to_jiffies(sp->rtoinfo.srto_max);
95 asoc->rto_min = msecs_to_jiffies(sp->rtoinfo.srto_min);
96
Frank Filz52ccb8e2005-12-22 11:36:46 -080097 /* Initialize the association's heartbeat interval based on the
98 * sock configured value.
99 */
100 asoc->hbinterval = msecs_to_jiffies(sp->hbinterval);
101
102 /* Initialize path max retrans value. */
103 asoc->pathmaxrxt = sp->pathmaxrxt;
104
Xin Long8a9c58d2018-07-02 18:21:12 +0800105 asoc->flowlabel = sp->flowlabel;
106 asoc->dscp = sp->dscp;
107
Frank Filz52ccb8e2005-12-22 11:36:46 -0800108 /* Set association default SACK delay */
109 asoc->sackdelay = msecs_to_jiffies(sp->sackdelay);
Wei Yongjund364d922008-05-09 15:13:26 -0700110 asoc->sackfreq = sp->sackfreq;
Frank Filz52ccb8e2005-12-22 11:36:46 -0800111
112 /* Set the association default flags controlling
113 * Heartbeat, SACK delay, and Path MTU Discovery.
114 */
115 asoc->param_flags = sp->param_flags;
116
wangweidong9d2c8812013-12-06 09:36:30 +0800117 /* Initialize the maximum number of new data packets that can be sent
Linus Torvalds1da177e2005-04-16 15:20:36 -0700118 * in a burst.
119 */
Vlad Yasevich70331572007-03-23 11:34:36 -0700120 asoc->max_burst = sp->max_burst;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700121
Xin Longa1e3a052018-11-18 16:08:52 +0800122 asoc->subscribe = sp->subscribe;
123
Vladislav Yasevich1e7d3d92005-11-11 16:06:16 -0800124 /* initialize association timers */
Vladislav Yasevich1e7d3d92005-11-11 16:06:16 -0800125 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_COOKIE] = asoc->rto_initial;
126 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_INIT] = asoc->rto_initial;
127 asoc->timeouts[SCTP_EVENT_TIMEOUT_T2_SHUTDOWN] = asoc->rto_initial;
Vladislav Yasevich1e7d3d92005-11-11 16:06:16 -0800128
129 /* sctpimpguide Section 2.12.2
130 * If the 'T5-shutdown-guard' timer is used, it SHOULD be set to the
131 * recommended value of 5 times 'RTO.Max'.
132 */
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +0900133 asoc->timeouts[SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD]
Vladislav Yasevich1e7d3d92005-11-11 16:06:16 -0800134 = 5 * asoc->rto_max;
135
Frank Filz52ccb8e2005-12-22 11:36:46 -0800136 asoc->timeouts[SCTP_EVENT_TIMEOUT_SACK] = asoc->sackdelay;
Neil Horman9f70f462013-12-10 06:48:15 -0500137 asoc->timeouts[SCTP_EVENT_TIMEOUT_AUTOCLOSE] = sp->autoclose * HZ;
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +0900138
Uwe Kleine-König421f91d2010-06-11 12:17:00 +0200139 /* Initializes the timers */
Pavel Emelyanovb24b8a22008-01-23 21:20:07 -0800140 for (i = SCTP_EVENT_TIMEOUT_NONE; i < SCTP_NUM_TIMEOUT_TYPES; ++i)
Kees Cook9c3b5752017-10-24 01:45:31 -0700141 timer_setup(&asoc->timers[i], sctp_timer_events[i], 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700142
143 /* Pull default initialization values from the sock options.
144 * Note: This assumes that the values have already been
145 * validated in the sock.
146 */
147 asoc->c.sinit_max_instreams = sp->initmsg.sinit_max_instreams;
148 asoc->c.sinit_num_ostreams = sp->initmsg.sinit_num_ostreams;
149 asoc->max_init_attempts = sp->initmsg.sinit_max_attempts;
150
151 asoc->max_init_timeo =
152 msecs_to_jiffies(sp->initmsg.sinit_max_init_timeo);
153
Linus Torvalds1da177e2005-04-16 15:20:36 -0700154 /* Set the local window size for receive.
155 * This is also the rcvbuf space per association.
156 * RFC 6 - A SCTP receiver MUST be able to receive a minimum of
157 * 1500 bytes in one SCTP packet.
158 */
Neil Horman049b3ff2005-11-11 16:08:24 -0800159 if ((sk->sk_rcvbuf/2) < SCTP_DEFAULT_MINWINDOW)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700160 asoc->rwnd = SCTP_DEFAULT_MINWINDOW;
161 else
Neil Horman049b3ff2005-11-11 16:08:24 -0800162 asoc->rwnd = sk->sk_rcvbuf/2;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700163
164 asoc->a_rwnd = asoc->rwnd;
165
Linus Torvalds1da177e2005-04-16 15:20:36 -0700166 /* Use my own max window until I learn something better. */
167 asoc->peer.rwnd = SCTP_DEFAULT_MAXWINDOW;
168
Neil Horman049b3ff2005-11-11 16:08:24 -0800169 /* Initialize the receive memory counter */
170 atomic_set(&asoc->rmem_alloc, 0);
171
Linus Torvalds1da177e2005-04-16 15:20:36 -0700172 init_waitqueue_head(&asoc->wait);
173
174 asoc->c.my_vtag = sctp_generate_tag(ep);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700175 asoc->c.my_port = ep->base.bind_addr.port;
176
177 asoc->c.initial_tsn = sctp_generate_tsn(ep);
178
179 asoc->next_tsn = asoc->c.initial_tsn;
180
181 asoc->ctsn_ack_point = asoc->next_tsn - 1;
182 asoc->adv_peer_ack_point = asoc->ctsn_ack_point;
183 asoc->highest_sacked = asoc->ctsn_ack_point;
184 asoc->last_cwr_tsn = asoc->ctsn_ack_point;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700185
Linus Torvalds1da177e2005-04-16 15:20:36 -0700186 /* ADDIP Section 4.1 Asconf Chunk Procedures
187 *
188 * When an endpoint has an ASCONF signaled change to be sent to the
189 * remote endpoint it should do the following:
190 * ...
191 * A2) a serial number should be assigned to the chunk. The serial
192 * number SHOULD be a monotonically increasing number. The serial
193 * numbers SHOULD be initialized at the start of the
194 * association to the same value as the initial TSN.
195 */
196 asoc->addip_serial = asoc->c.initial_tsn;
Xin Longcc16f002017-01-18 00:44:42 +0800197 asoc->strreset_outseq = asoc->c.initial_tsn;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700198
David S. Miller79af02c2005-07-08 21:47:49 -0700199 INIT_LIST_HEAD(&asoc->addip_chunk_list);
Vlad Yasevicha08de642007-12-20 14:11:47 -0800200 INIT_LIST_HEAD(&asoc->asconf_ack_list);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700201
202 /* Make an empty list of remote transport addresses. */
203 INIT_LIST_HEAD(&asoc->peer.transport_addr_list);
204
205 /* RFC 2960 5.1 Normal Establishment of an Association
206 *
207 * After the reception of the first data chunk in an
208 * association the endpoint must immediately respond with a
209 * sack to acknowledge the data chunk. Subsequent
210 * acknowledgements should be done as described in Section
211 * 6.2.
212 *
213 * [We implement this by telling a new association that it
214 * already received one packet.]
215 */
216 asoc->peer.sack_needed = 1;
Neil Horman42448542012-06-30 03:04:26 +0000217 asoc->peer.sack_generation = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700218
Linus Torvalds1da177e2005-04-16 15:20:36 -0700219 /* Create an input queue. */
220 sctp_inq_init(&asoc->base.inqueue);
David Howellsc4028952006-11-22 14:57:56 +0000221 sctp_inq_set_th_handler(&asoc->base.inqueue, sctp_assoc_bh_rcv);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700222
223 /* Create an output queue. */
224 sctp_outq_init(asoc, &asoc->outqueue);
225
226 if (!sctp_ulpq_init(&asoc->ulpq, asoc))
227 goto fail_init;
228
Xin Longff356412017-05-31 16:36:32 +0800229 if (sctp_stream_init(&asoc->stream, asoc->c.sinit_num_ostreams,
230 0, gfp))
Xin Long3dbcc102017-03-30 01:00:53 +0800231 goto fail_init;
232
Xin Long4135cce2018-11-27 19:11:50 +0800233 /* Initialize default path MTU. */
234 asoc->pathmtu = sp->pathmtu;
235 sctp_assoc_update_frag_point(asoc);
236
Linus Torvalds1da177e2005-04-16 15:20:36 -0700237 /* Assume that peer would support both address types unless we are
238 * told otherwise.
239 */
240 asoc->peer.ipv4_address = 1;
Wei Yongjuna2c39582009-04-07 16:35:11 +0800241 if (asoc->base.sk->sk_family == PF_INET6)
242 asoc->peer.ipv6_address = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700243 INIT_LIST_HEAD(&asoc->asocs);
244
Linus Torvalds1da177e2005-04-16 15:20:36 -0700245 asoc->default_stream = sp->default_stream;
246 asoc->default_ppid = sp->default_ppid;
247 asoc->default_flags = sp->default_flags;
248 asoc->default_context = sp->default_context;
249 asoc->default_timetolive = sp->default_timetolive;
Ivan Skytte Jorgensen6ab792f2006-12-13 16:34:22 -0800250 asoc->default_rcv_context = sp->default_rcv_context;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700251
Vlad Yasevicha29a5bd2007-09-16 19:31:35 -0700252 /* AUTH related initializations */
253 INIT_LIST_HEAD(&asoc->endpoint_shared_keys);
Xin Long58194772017-03-20 18:00:28 +0800254 if (sctp_auth_asoc_copy_shkeys(ep, asoc, gfp))
Xin Long3dbcc102017-03-30 01:00:53 +0800255 goto stream_free;
Vlad Yasevicha29a5bd2007-09-16 19:31:35 -0700256
257 asoc->active_key_id = ep->active_key_id;
Xin Long9fb657a2017-01-18 00:44:46 +0800258 asoc->strreset_enable = ep->strreset_enable;
Vlad Yasevicha29a5bd2007-09-16 19:31:35 -0700259
Vlad Yasevicha29a5bd2007-09-16 19:31:35 -0700260 /* Save the hmacs and chunks list into this association */
261 if (ep->auth_hmacs_list)
262 memcpy(asoc->c.auth_hmacs, ep->auth_hmacs_list,
263 ntohs(ep->auth_hmacs_list->param_hdr.length));
264 if (ep->auth_chunk_list)
265 memcpy(asoc->c.auth_chunks, ep->auth_chunk_list,
266 ntohs(ep->auth_chunk_list->param_hdr.length));
267
268 /* Get the AUTH random number for this association */
Xin Long3c918702017-06-30 11:52:16 +0800269 p = (struct sctp_paramhdr *)asoc->c.auth_random;
Vlad Yasevicha29a5bd2007-09-16 19:31:35 -0700270 p->type = SCTP_PARAM_RANDOM;
Xin Long3c918702017-06-30 11:52:16 +0800271 p->length = htons(sizeof(*p) + SCTP_AUTH_RANDOM_LENGTH);
Vlad Yasevicha29a5bd2007-09-16 19:31:35 -0700272 get_random_bytes(p+1, SCTP_AUTH_RANDOM_LENGTH);
273
Linus Torvalds1da177e2005-04-16 15:20:36 -0700274 return asoc;
275
Xin Long3dbcc102017-03-30 01:00:53 +0800276stream_free:
Xin Longcee360a2017-05-31 16:36:31 +0800277 sctp_stream_free(&asoc->stream);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700278fail_init:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700279 sock_put(asoc->base.sk);
Daniel Borkmann2e0c9e72013-06-14 18:24:07 +0200280 sctp_endpoint_put(asoc->ep);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700281 return NULL;
282}
283
284/* Allocate and initialize a new association */
285struct sctp_association *sctp_association_new(const struct sctp_endpoint *ep,
Xin Long1c662012017-08-05 19:59:54 +0800286 const struct sock *sk,
287 enum sctp_scope scope, gfp_t gfp)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700288{
289 struct sctp_association *asoc;
290
Daniel Borkmann939cfa72013-06-17 11:40:04 +0200291 asoc = kzalloc(sizeof(*asoc), gfp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700292 if (!asoc)
293 goto fail;
294
295 if (!sctp_association_init(asoc, ep, sk, scope, gfp))
296 goto fail_init;
297
Linus Torvalds1da177e2005-04-16 15:20:36 -0700298 SCTP_DBG_OBJCNT_INC(assoc);
Daniel Borkmannbb333812013-06-28 19:49:40 +0200299
300 pr_debug("Created asoc %p\n", asoc);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700301
302 return asoc;
303
304fail_init:
305 kfree(asoc);
306fail:
307 return NULL;
308}
309
310/* Free this association if possible. There may still be users, so
311 * the actual deallocation may be delayed.
312 */
313void sctp_association_free(struct sctp_association *asoc)
314{
315 struct sock *sk = asoc->base.sk;
316 struct sctp_transport *transport;
317 struct list_head *pos, *temp;
318 int i;
319
Vlad Yasevichde76e692006-10-30 18:55:11 -0800320 /* Only real associations count against the endpoint, so
321 * don't bother for if this is a temporary association.
322 */
Xufeng Zhangd3217b12014-06-12 10:53:36 +0800323 if (!list_empty(&asoc->asocs)) {
Vlad Yasevichde76e692006-10-30 18:55:11 -0800324 list_del(&asoc->asocs);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700325
Vlad Yasevichde76e692006-10-30 18:55:11 -0800326 /* Decrement the backlog value for a TCP-style listening
327 * socket.
328 */
329 if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING))
Eric Dumazet7976a112019-11-05 14:11:52 -0800330 sk_acceptq_removed(sk);
Vlad Yasevichde76e692006-10-30 18:55:11 -0800331 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700332
333 /* Mark as dead, so other users can know this structure is
334 * going away.
335 */
Daniel Borkmann0022d2d2013-04-15 03:27:18 +0000336 asoc->base.dead = true;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700337
338 /* Dispose of any data lying around in the outqueue. */
339 sctp_outq_free(&asoc->outqueue);
340
341 /* Dispose of any pending messages for the upper layer. */
342 sctp_ulpq_free(&asoc->ulpq);
343
344 /* Dispose of any pending chunks on the inqueue. */
345 sctp_inq_free(&asoc->base.inqueue);
346
Vlad Yasevich8e1ee182008-10-08 14:18:39 -0700347 sctp_tsnmap_free(&asoc->peer.tsn_map);
348
Xin Longa8386312017-01-06 22:18:33 +0800349 /* Free stream information. */
Xin Longcee360a2017-05-31 16:36:31 +0800350 sctp_stream_free(&asoc->stream);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700351
Xin Long7b9438d2017-01-18 00:44:43 +0800352 if (asoc->strreset_chunk)
353 sctp_chunk_free(asoc->strreset_chunk);
354
Linus Torvalds1da177e2005-04-16 15:20:36 -0700355 /* Clean up the bound address list. */
356 sctp_bind_addr_free(&asoc->base.bind_addr);
357
358 /* Do we need to go through all of our timers and
359 * delete them? To be safe we will try to delete all, but we
360 * should be able to go through and make a guess based
361 * on our state.
362 */
363 for (i = SCTP_EVENT_TIMEOUT_NONE; i < SCTP_NUM_TIMEOUT_TYPES; ++i) {
Ying Xue25cc4ae92013-02-03 20:32:57 +0000364 if (del_timer(&asoc->timers[i]))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700365 sctp_association_put(asoc);
366 }
367
368 /* Free peer's cached cookie. */
Jesper Juhla51482b2005-11-08 09:41:34 -0800369 kfree(asoc->peer.cookie);
Vlad Yasevich730fc3d2007-09-16 19:32:11 -0700370 kfree(asoc->peer.peer_random);
371 kfree(asoc->peer.peer_chunks);
372 kfree(asoc->peer.peer_hmacs);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700373
374 /* Release the transport structures. */
375 list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
376 transport = list_entry(pos, struct sctp_transport, transports);
Thomas Graf45122ca262012-12-06 09:25:05 +0000377 list_del_rcu(pos);
Xin Long4f008782015-12-30 23:50:47 +0800378 sctp_unhash_transport(transport);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700379 sctp_transport_free(transport);
380 }
381
Frank Filz3f7a87d2005-06-20 13:14:57 -0700382 asoc->peer.transport_count = 0;
383
Wei Yongjuna000c012011-05-29 23:23:36 +0000384 sctp_asconf_queue_teardown(asoc);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700385
Michio Honda8a07eb02011-04-26 20:19:36 +0900386 /* Free pending address space being deleted */
Markus Elfring7d37d0c2015-01-31 18:10:03 +0100387 kfree(asoc->asconf_addr_del_pending);
Michio Honda8a07eb02011-04-26 20:19:36 +0900388
Vlad Yasevicha29a5bd2007-09-16 19:31:35 -0700389 /* AUTH - Free the endpoint shared keys */
390 sctp_auth_destroy_keys(&asoc->endpoint_shared_keys);
391
392 /* AUTH - Free the association shared key */
393 sctp_auth_key_put(asoc->asoc_shared_key);
394
Linus Torvalds1da177e2005-04-16 15:20:36 -0700395 sctp_association_put(asoc);
396}
397
398/* Cleanup and free up an association. */
399static void sctp_association_destroy(struct sctp_association *asoc)
400{
Daniel Borkmannbb333812013-06-28 19:49:40 +0200401 if (unlikely(!asoc->base.dead)) {
402 WARN(1, "Attempt to destroy undead association %p!\n", asoc);
403 return;
404 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700405
406 sctp_endpoint_put(asoc->ep);
407 sock_put(asoc->base.sk);
408
409 if (asoc->assoc_id != 0) {
410 spin_lock_bh(&sctp_assocs_id_lock);
411 idr_remove(&sctp_assocs_id, asoc->assoc_id);
412 spin_unlock_bh(&sctp_assocs_id_lock);
413 }
414
Ilpo Järvinen547b7922008-07-25 21:43:18 -0700415 WARN_ON(atomic_read(&asoc->rmem_alloc));
Neil Horman049b3ff2005-11-11 16:08:24 -0800416
Xin Longfb6df5a2018-12-01 01:36:59 +0800417 kfree_rcu(asoc, rcu);
Daniel Borkmannff2266c2013-04-15 03:27:17 +0000418 SCTP_DBG_OBJCNT_DEC(assoc);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700419}
420
421/* Change the primary destination address for the peer. */
422void sctp_assoc_set_primary(struct sctp_association *asoc,
423 struct sctp_transport *transport)
424{
Vlad Yasevich319fa2a2008-06-16 17:00:29 -0700425 int changeover = 0;
426
427 /* it's a changeover only if we already have a primary path
428 * that we are changing
429 */
430 if (asoc->peer.primary_path != NULL &&
431 asoc->peer.primary_path != transport)
432 changeover = 1 ;
433
Linus Torvalds1da177e2005-04-16 15:20:36 -0700434 asoc->peer.primary_path = transport;
Jonas Falkevik50ce4c02020-05-27 11:59:43 +0200435 sctp_ulpevent_notify_peer_addr_change(transport,
Xin Long5cd0b912019-10-08 19:27:35 +0800436 SCTP_ADDR_MADE_PRIM, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700437
438 /* Set a default msg_name for events. */
439 memcpy(&asoc->peer.primary_addr, &transport->ipaddr,
440 sizeof(union sctp_addr));
441
442 /* If the primary path is changing, assume that the
443 * user wants to use this new path.
444 */
Sridhar Samudralaad8fec12006-07-21 14:48:50 -0700445 if ((transport->state == SCTP_ACTIVE) ||
446 (transport->state == SCTP_UNKNOWN))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700447 asoc->peer.active_path = transport;
448
449 /*
450 * SFR-CACC algorithm:
451 * Upon the receipt of a request to change the primary
452 * destination address, on the data structure for the new
453 * primary destination, the sender MUST do the following:
454 *
455 * 1) If CHANGEOVER_ACTIVE is set, then there was a switch
456 * to this destination address earlier. The sender MUST set
457 * CYCLING_CHANGEOVER to indicate that this switch is a
458 * double switch to the same destination address.
Vlad Yaseviche0e9db12009-11-23 15:53:57 -0500459 *
460 * Really, only bother is we have data queued or outstanding on
461 * the association.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700462 */
Vlad Yaseviche0e9db12009-11-23 15:53:57 -0500463 if (!asoc->outqueue.outstanding_bytes && !asoc->outqueue.out_qlen)
464 return;
465
Linus Torvalds1da177e2005-04-16 15:20:36 -0700466 if (transport->cacc.changeover_active)
Vlad Yasevich319fa2a2008-06-16 17:00:29 -0700467 transport->cacc.cycling_changeover = changeover;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700468
469 /* 2) The sender MUST set CHANGEOVER_ACTIVE to indicate that
470 * a changeover has occurred.
471 */
Vlad Yasevich319fa2a2008-06-16 17:00:29 -0700472 transport->cacc.changeover_active = changeover;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700473
474 /* 3) The sender MUST store the next TSN to be sent in
475 * next_tsn_at_change.
476 */
477 transport->cacc.next_tsn_at_change = asoc->next_tsn;
478}
479
Frank Filz3f7a87d2005-06-20 13:14:57 -0700480/* Remove a transport from an association. */
481void sctp_assoc_rm_peer(struct sctp_association *asoc,
482 struct sctp_transport *peer)
483{
Xin Longdf132ef2018-10-29 23:10:29 +0800484 struct sctp_transport *transport;
485 struct list_head *pos;
486 struct sctp_chunk *ch;
Frank Filz3f7a87d2005-06-20 13:14:57 -0700487
Daniel Borkmannbb333812013-06-28 19:49:40 +0200488 pr_debug("%s: association:%p addr:%pISpc\n",
489 __func__, asoc, &peer->ipaddr.sa);
Frank Filz3f7a87d2005-06-20 13:14:57 -0700490
491 /* If we are to remove the current retran_path, update it
492 * to the next peer before removing this peer from the list.
493 */
494 if (asoc->peer.retran_path == peer)
495 sctp_assoc_update_retran_path(asoc);
496
497 /* Remove this peer from the list. */
Thomas Graf45122ca262012-12-06 09:25:05 +0000498 list_del_rcu(&peer->transports);
Xin Long4f008782015-12-30 23:50:47 +0800499 /* Remove this peer from the transport hashtable */
500 sctp_unhash_transport(peer);
Frank Filz3f7a87d2005-06-20 13:14:57 -0700501
502 /* Get the first transport of asoc. */
503 pos = asoc->peer.transport_addr_list.next;
504 transport = list_entry(pos, struct sctp_transport, transports);
505
506 /* Update any entries that match the peer to be deleted. */
507 if (asoc->peer.primary_path == peer)
508 sctp_assoc_set_primary(asoc, transport);
509 if (asoc->peer.active_path == peer)
510 asoc->peer.active_path = transport;
Wei Yongjun9494c7c2011-04-12 15:22:22 +0000511 if (asoc->peer.retran_path == peer)
512 asoc->peer.retran_path = transport;
Frank Filz3f7a87d2005-06-20 13:14:57 -0700513 if (asoc->peer.last_data_from == peer)
514 asoc->peer.last_data_from = transport;
515
Xin Long7b9438d2017-01-18 00:44:43 +0800516 if (asoc->strreset_chunk &&
517 asoc->strreset_chunk->transport == peer) {
518 asoc->strreset_chunk->transport = transport;
519 sctp_transport_reset_reconf_timer(transport);
520 }
521
Frank Filz3f7a87d2005-06-20 13:14:57 -0700522 /* If we remove the transport an INIT was last sent to, set it to
523 * NULL. Combined with the update of the retran path above, this
524 * will cause the next INIT to be sent to the next available
525 * transport, maintaining the cycle.
526 */
527 if (asoc->init_last_sent_to == peer)
528 asoc->init_last_sent_to = NULL;
529
Wei Yongjun6345b192009-04-26 23:13:35 +0800530 /* If we remove the transport an SHUTDOWN was last sent to, set it
531 * to NULL. Combined with the update of the retran path above, this
532 * will cause the next SHUTDOWN to be sent to the next available
533 * transport, maintaining the cycle.
534 */
535 if (asoc->shutdown_last_sent_to == peer)
536 asoc->shutdown_last_sent_to = NULL;
537
Wei Yongjun10a43ce2009-04-26 23:14:42 +0800538 /* If we remove the transport an ASCONF was last sent to, set it to
539 * NULL.
540 */
541 if (asoc->addip_last_asconf &&
542 asoc->addip_last_asconf->transport == peer)
543 asoc->addip_last_asconf->transport = NULL;
544
Vlad Yasevich31b02e12009-09-04 18:21:00 -0400545 /* If we have something on the transmitted list, we have to
546 * save it off. The best place is the active path.
547 */
548 if (!list_empty(&peer->transmitted)) {
549 struct sctp_transport *active = asoc->peer.active_path;
Vlad Yasevich31b02e12009-09-04 18:21:00 -0400550
551 /* Reset the transport of each chunk on this list */
552 list_for_each_entry(ch, &peer->transmitted,
553 transmitted_list) {
554 ch->transport = NULL;
555 ch->rtt_in_progress = 0;
556 }
557
558 list_splice_tail_init(&peer->transmitted,
559 &active->transmitted);
560
561 /* Start a T3 timer here in case it wasn't running so
562 * that these migrated packets have a chance to get
wangweidong2bccbad2013-10-26 16:06:30 +0800563 * retransmitted.
Vlad Yasevich31b02e12009-09-04 18:21:00 -0400564 */
565 if (!timer_pending(&active->T3_rtx_timer))
566 if (!mod_timer(&active->T3_rtx_timer,
567 jiffies + active->rto))
568 sctp_transport_hold(active);
569 }
570
Xin Longdf132ef2018-10-29 23:10:29 +0800571 list_for_each_entry(ch, &asoc->outqueue.out_chunk_list, list)
572 if (ch->transport == peer)
573 ch->transport = NULL;
574
Frank Filz3f7a87d2005-06-20 13:14:57 -0700575 asoc->peer.transport_count--;
576
Jonas Falkevik50ce4c02020-05-27 11:59:43 +0200577 sctp_ulpevent_notify_peer_addr_change(peer, SCTP_ADDR_REMOVED, 0);
Frank Filz3f7a87d2005-06-20 13:14:57 -0700578 sctp_transport_free(peer);
579}
580
Linus Torvalds1da177e2005-04-16 15:20:36 -0700581/* Add a transport address to an association. */
582struct sctp_transport *sctp_assoc_add_peer(struct sctp_association *asoc,
583 const union sctp_addr *addr,
Al Virodd0fc662005-10-07 07:46:04 +0100584 const gfp_t gfp,
Frank Filz3f7a87d2005-06-20 13:14:57 -0700585 const int peer_state)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700586{
587 struct sctp_transport *peer;
588 struct sctp_sock *sp;
589 unsigned short port;
590
591 sp = sctp_sk(asoc->base.sk);
592
593 /* AF_INET and AF_INET6 share common port field. */
Al Viro4bdf4b52006-11-20 17:10:20 -0800594 port = ntohs(addr->v4.sin_port);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700595
Daniel Borkmannbb333812013-06-28 19:49:40 +0200596 pr_debug("%s: association:%p addr:%pISpc state:%d\n", __func__,
597 asoc, &addr->sa, peer_state);
Frank Filz3f7a87d2005-06-20 13:14:57 -0700598
Linus Torvalds1da177e2005-04-16 15:20:36 -0700599 /* Set the port if it has not been set yet. */
600 if (0 == asoc->peer.port)
601 asoc->peer.port = port;
602
603 /* Check to see if this is a duplicate. */
604 peer = sctp_assoc_lookup_paddr(asoc, addr);
Frank Filz3f7a87d2005-06-20 13:14:57 -0700605 if (peer) {
Vlad Yasevichadd52372008-09-18 16:28:27 -0700606 /* An UNKNOWN state is only set on transports added by
607 * user in sctp_connectx() call. Such transports should be
608 * considered CONFIRMED per RFC 4960, Section 5.4.
609 */
Sridhar Samudralaad8fec12006-07-21 14:48:50 -0700610 if (peer->state == SCTP_UNKNOWN) {
Vlad Yasevichadd52372008-09-18 16:28:27 -0700611 peer->state = SCTP_ACTIVE;
Sridhar Samudralaad8fec12006-07-21 14:48:50 -0700612 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700613 return peer;
Frank Filz3f7a87d2005-06-20 13:14:57 -0700614 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700615
Xin Long4e7696d2019-12-09 13:45:18 +0800616 peer = sctp_transport_new(asoc->base.net, addr, gfp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700617 if (!peer)
618 return NULL;
619
620 sctp_transport_set_owner(peer, asoc);
621
Frank Filz52ccb8e2005-12-22 11:36:46 -0800622 /* Initialize the peer's heartbeat interval based on the
623 * association configured value.
624 */
625 peer->hbinterval = asoc->hbinterval;
626
627 /* Set the path max_retrans. */
628 peer->pathmaxrxt = asoc->pathmaxrxt;
629
wangweidong2bccbad2013-10-26 16:06:30 +0800630 /* And the partial failure retrans threshold */
Neil Horman5aa93bc2012-07-21 07:56:07 +0000631 peer->pf_retrans = asoc->pf_retrans;
Xin Long34515e92019-11-08 13:20:35 +0800632 /* And the primary path switchover retrans threshold */
633 peer->ps_retrans = asoc->ps_retrans;
Neil Horman5aa93bc2012-07-21 07:56:07 +0000634
Frank Filz52ccb8e2005-12-22 11:36:46 -0800635 /* Initialize the peer's SACK delay timeout based on the
636 * association configured value.
637 */
638 peer->sackdelay = asoc->sackdelay;
Wei Yongjund364d922008-05-09 15:13:26 -0700639 peer->sackfreq = asoc->sackfreq;
Frank Filz52ccb8e2005-12-22 11:36:46 -0800640
Xin Long4be41392018-07-02 18:21:14 +0800641 if (addr->sa.sa_family == AF_INET6) {
642 __be32 info = addr->v6.sin6_flowinfo;
643
644 if (info) {
645 peer->flowlabel = ntohl(info & IPV6_FLOWLABEL_MASK);
646 peer->flowlabel |= SCTP_FLOWLABEL_SET_MASK;
647 } else {
648 peer->flowlabel = asoc->flowlabel;
649 }
650 }
Xin Long8a9c58d2018-07-02 18:21:12 +0800651 peer->dscp = asoc->dscp;
652
Frank Filz52ccb8e2005-12-22 11:36:46 -0800653 /* Enable/disable heartbeat, SACK delay, and path MTU discovery
654 * based on association setting.
655 */
656 peer->param_flags = asoc->param_flags;
657
Linus Torvalds1da177e2005-04-16 15:20:36 -0700658 /* Initialize the pmtu of the transport. */
Marcelo Ricardo Leitner800e00c2018-04-26 16:58:51 -0300659 sctp_transport_route(peer, NULL, sp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700660
661 /* If this is the first transport addr on this association,
662 * initialize the association PMTU to the peer's PMTU.
663 * If not and the current association PMTU is higher than the new
664 * peer's PMTU, reset the association PMTU to the new peer's PMTU.
665 */
Marcelo Ricardo Leitnerc4b28932018-04-26 16:58:53 -0300666 sctp_assoc_set_pmtu(asoc, asoc->pathmtu ?
667 min_t(int, peer->pathmtu, asoc->pathmtu) :
668 peer->pathmtu);
Daniel Borkmannbb333812013-06-28 19:49:40 +0200669
Florian Westphal6d0ccba2008-07-18 23:04:39 -0700670 peer->pmtu_pending = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700671
Linus Torvalds1da177e2005-04-16 15:20:36 -0700672 /* The asoc->peer.port might not be meaningful yet, but
673 * initialize the packet structure anyway.
674 */
675 sctp_packet_init(&peer->packet, peer, asoc->base.bind_addr.port,
676 asoc->peer.port);
677
678 /* 7.2.1 Slow-Start
679 *
680 * o The initial cwnd before DATA transmission or after a sufficiently
681 * long idle period MUST be set to
682 * min(4*MTU, max(2*MTU, 4380 bytes))
683 *
684 * o The initial value of ssthresh MAY be arbitrarily high
685 * (for example, implementations MAY use the size of the
686 * receiver advertised window).
687 */
Frank Filz52ccb8e2005-12-22 11:36:46 -0800688 peer->cwnd = min(4*asoc->pathmtu, max_t(__u32, 2*asoc->pathmtu, 4380));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700689
690 /* At this point, we may not have the receiver's advertised window,
691 * so initialize ssthresh to the default value and it will be set
692 * later when we process the INIT.
693 */
694 peer->ssthresh = SCTP_DEFAULT_MAXWINDOW;
695
696 peer->partial_bytes_acked = 0;
697 peer->flight_size = 0;
Vlad Yasevich46d5a802009-11-23 15:54:00 -0500698 peer->burst_limited = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700699
Linus Torvalds1da177e2005-04-16 15:20:36 -0700700 /* Set the transport's RTO.initial value */
701 peer->rto = asoc->rto_initial;
Michele Baldessari196d6752012-12-01 04:49:42 +0000702 sctp_max_rto(asoc, peer);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700703
Frank Filz3f7a87d2005-06-20 13:14:57 -0700704 /* Set the peer's active state. */
705 peer->state = peer_state;
706
Xin Long7fda7022016-11-15 23:23:11 +0800707 /* Add this peer into the transport hashtable */
708 if (sctp_hash_transport(peer)) {
709 sctp_transport_free(peer);
710 return NULL;
711 }
712
Linus Torvalds1da177e2005-04-16 15:20:36 -0700713 /* Attach the remote transport to our asoc. */
Thomas Graf45122ca262012-12-06 09:25:05 +0000714 list_add_tail_rcu(&peer->transports, &asoc->peer.transport_addr_list);
Frank Filz3f7a87d2005-06-20 13:14:57 -0700715 asoc->peer.transport_count++;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700716
Jonas Falkevik50ce4c02020-05-27 11:59:43 +0200717 sctp_ulpevent_notify_peer_addr_change(peer, SCTP_ADDR_ADDED, 0);
Xin Long4b774032019-10-08 19:27:33 +0800718
Linus Torvalds1da177e2005-04-16 15:20:36 -0700719 /* If we do not yet have a primary path, set one. */
720 if (!asoc->peer.primary_path) {
721 sctp_assoc_set_primary(asoc, peer);
722 asoc->peer.retran_path = peer;
723 }
724
Vlad Yasevichfbdf5012010-04-30 22:39:26 -0400725 if (asoc->peer.active_path == asoc->peer.retran_path &&
726 peer->state != SCTP_UNCONFIRMED) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700727 asoc->peer.retran_path = peer;
Frank Filz3f7a87d2005-06-20 13:14:57 -0700728 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700729
730 return peer;
731}
732
733/* Delete a transport address from an association. */
734void sctp_assoc_del_peer(struct sctp_association *asoc,
735 const union sctp_addr *addr)
736{
737 struct list_head *pos;
738 struct list_head *temp;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700739 struct sctp_transport *transport;
740
741 list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
742 transport = list_entry(pos, struct sctp_transport, transports);
743 if (sctp_cmp_addr_exact(addr, &transport->ipaddr)) {
Frank Filz3f7a87d2005-06-20 13:14:57 -0700744 /* Do book keeping for removing the peer and free it. */
745 sctp_assoc_rm_peer(asoc, transport);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700746 break;
747 }
748 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700749}
750
751/* Lookup a transport by address. */
752struct sctp_transport *sctp_assoc_lookup_paddr(
753 const struct sctp_association *asoc,
754 const union sctp_addr *address)
755{
756 struct sctp_transport *t;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700757
758 /* Cycle through all transports searching for a peer address. */
759
Robert P. J. Day9dbc15f02008-04-12 18:54:24 -0700760 list_for_each_entry(t, &asoc->peer.transport_addr_list,
761 transports) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700762 if (sctp_cmp_addr_exact(address, &t->ipaddr))
763 return t;
764 }
765
766 return NULL;
767}
768
Vlad Yasevich42e30bf2007-12-20 14:08:56 -0800769/* Remove all transports except a give one */
770void sctp_assoc_del_nonprimary_peers(struct sctp_association *asoc,
771 struct sctp_transport *primary)
772{
773 struct sctp_transport *temp;
774 struct sctp_transport *t;
775
776 list_for_each_entry_safe(t, temp, &asoc->peer.transport_addr_list,
777 transports) {
778 /* if the current transport is not the primary one, delete it */
779 if (t != primary)
780 sctp_assoc_rm_peer(asoc, t);
781 }
Vlad Yasevich42e30bf2007-12-20 14:08:56 -0800782}
783
Linus Torvalds1da177e2005-04-16 15:20:36 -0700784/* Engage in transport control operations.
785 * Mark the transport up or down and send a notification to the user.
786 * Select and update the new active and retran paths.
787 */
788void sctp_assoc_control_transport(struct sctp_association *asoc,
789 struct sctp_transport *transport,
Xin Long0ceaeeb2017-08-05 19:59:55 +0800790 enum sctp_transport_cmd command,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700791 sctp_sn_error_t error)
792{
Xin Long768e1512019-11-08 13:20:33 +0800793 int spc_state = SCTP_ADDR_AVAILABLE;
Neil Horman5aa93bc2012-07-21 07:56:07 +0000794 bool ulp_notify = true;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700795
796 /* Record the transition on the transport. */
797 switch (command) {
798 case SCTP_TRANSPORT_UP:
Vlad Yasevich1ae41142007-03-23 11:32:26 -0700799 /* If we are moving from UNCONFIRMED state due
800 * to heartbeat success, report the SCTP_ADDR_CONFIRMED
801 * state to the user, otherwise report SCTP_ADDR_AVAILABLE.
802 */
Xin Long768e1512019-11-08 13:20:33 +0800803 if (transport->state == SCTP_PF &&
804 asoc->pf_expose != SCTP_PF_EXPOSE_ENABLE)
Neil Horman5aa93bc2012-07-21 07:56:07 +0000805 ulp_notify = false;
Xin Long768e1512019-11-08 13:20:33 +0800806 else if (transport->state == SCTP_UNCONFIRMED &&
807 error == SCTP_HEARTBEAT_SUCCESS)
808 spc_state = SCTP_ADDR_CONFIRMED;
809
Frank Filz3f7a87d2005-06-20 13:14:57 -0700810 transport->state = SCTP_ACTIVE;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700811 break;
812
813 case SCTP_TRANSPORT_DOWN:
Vlad Yasevich40187882009-06-23 11:28:05 -0400814 /* If the transport was never confirmed, do not transition it
815 * to inactive state. Also, release the cached route since
816 * there may be a better route next time.
Vlad Yasevichcc756892007-08-24 19:30:25 +0900817 */
Xin Long768e1512019-11-08 13:20:33 +0800818 if (transport->state != SCTP_UNCONFIRMED) {
Vlad Yasevichcc756892007-08-24 19:30:25 +0900819 transport->state = SCTP_INACTIVE;
Xin Long768e1512019-11-08 13:20:33 +0800820 spc_state = SCTP_ADDR_UNREACHABLE;
821 } else {
Julian Anastasovc86a7732017-02-06 23:14:13 +0200822 sctp_transport_dst_release(transport);
zhuyj061079a2014-08-20 17:31:43 +0800823 ulp_notify = false;
Vlad Yasevich40187882009-06-23 11:28:05 -0400824 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700825 break;
826
Neil Horman5aa93bc2012-07-21 07:56:07 +0000827 case SCTP_TRANSPORT_PF:
828 transport->state = SCTP_PF;
Xin Long768e1512019-11-08 13:20:33 +0800829 if (asoc->pf_expose != SCTP_PF_EXPOSE_ENABLE)
830 ulp_notify = false;
831 else
832 spc_state = SCTP_ADDR_POTENTIALLY_FAILED;
Neil Horman5aa93bc2012-07-21 07:56:07 +0000833 break;
834
Linus Torvalds1da177e2005-04-16 15:20:36 -0700835 default:
836 return;
Stephen Hemminger3ff50b72007-04-20 17:09:22 -0700837 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700838
Daniel Borkmannb82e8f32014-06-11 18:19:29 +0200839 /* Generate and send a SCTP_PEER_ADDR_CHANGE notification
840 * to the user.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700841 */
Xin Long4b774032019-10-08 19:27:33 +0800842 if (ulp_notify)
Jonas Falkevik50ce4c02020-05-27 11:59:43 +0200843 sctp_ulpevent_notify_peer_addr_change(transport,
Xin Long4b774032019-10-08 19:27:33 +0800844 spc_state, error);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700845
846 /* Select new active and retran paths. */
Daniel Borkmannb82e8f32014-06-11 18:19:29 +0200847 sctp_select_active_and_retran_path(asoc);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700848}
849
850/* Hold a reference to an association. */
851void sctp_association_hold(struct sctp_association *asoc)
852{
Reshetova, Elenac6384572017-07-04 15:53:28 +0300853 refcount_inc(&asoc->base.refcnt);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700854}
855
856/* Release a reference to an association and cleanup
857 * if there are no more references.
858 */
859void sctp_association_put(struct sctp_association *asoc)
860{
Reshetova, Elenac6384572017-07-04 15:53:28 +0300861 if (refcount_dec_and_test(&asoc->base.refcnt))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700862 sctp_association_destroy(asoc);
863}
864
865/* Allocate the next TSN, Transmission Sequence Number, for the given
866 * association.
867 */
868__u32 sctp_association_get_next_tsn(struct sctp_association *asoc)
869{
870 /* From Section 1.6 Serial Number Arithmetic:
871 * Transmission Sequence Numbers wrap around when they reach
872 * 2**32 - 1. That is, the next TSN a DATA chunk MUST use
873 * after transmitting TSN = 2*32 - 1 is TSN = 0.
874 */
875 __u32 retval = asoc->next_tsn;
876 asoc->next_tsn++;
877 asoc->unack_data++;
878
879 return retval;
880}
881
882/* Compare two addresses to see if they match. Wildcard addresses
883 * only match themselves.
884 */
885int sctp_cmp_addr_exact(const union sctp_addr *ss1,
886 const union sctp_addr *ss2)
887{
888 struct sctp_af *af;
889
890 af = sctp_get_af_specific(ss1->sa.sa_family);
891 if (unlikely(!af))
892 return 0;
893
894 return af->cmp_addr(ss1, ss2);
895}
896
897/* Return an ecne chunk to get prepended to a packet.
898 * Note: We are sly and return a shared, prealloced chunk. FIXME:
899 * No we don't, but we could/should.
900 */
901struct sctp_chunk *sctp_get_ecne_prepend(struct sctp_association *asoc)
902{
wangweidong8b7318d2013-12-06 09:36:28 +0800903 if (!asoc->need_ecne)
904 return NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700905
906 /* Send ECNE if needed.
907 * Not being able to allocate a chunk here is not deadly.
908 */
wangweidong8b7318d2013-12-06 09:36:28 +0800909 return sctp_make_ecne(asoc, asoc->last_ecne_tsn);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700910}
911
912/*
913 * Find which transport this TSN was sent on.
914 */
915struct sctp_transport *sctp_assoc_lookup_tsn(struct sctp_association *asoc,
916 __u32 tsn)
917{
918 struct sctp_transport *active;
919 struct sctp_transport *match;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700920 struct sctp_transport *transport;
921 struct sctp_chunk *chunk;
Al Virodbc16db2006-11-20 17:01:42 -0800922 __be32 key = htonl(tsn);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700923
924 match = NULL;
925
926 /*
927 * FIXME: In general, find a more efficient data structure for
928 * searching.
929 */
930
931 /*
932 * The general strategy is to search each transport's transmitted
933 * list. Return which transport this TSN lives on.
934 *
935 * Let's be hopeful and check the active_path first.
936 * Another optimization would be to know if there is only one
937 * outbound path and not have to look for the TSN at all.
938 *
939 */
940
941 active = asoc->peer.active_path;
942
Robert P. J. Day9dbc15f02008-04-12 18:54:24 -0700943 list_for_each_entry(chunk, &active->transmitted,
944 transmitted_list) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700945
946 if (key == chunk->subh.data_hdr->tsn) {
947 match = active;
948 goto out;
949 }
950 }
951
952 /* If not found, go search all the other transports. */
Robert P. J. Day9dbc15f02008-04-12 18:54:24 -0700953 list_for_each_entry(transport, &asoc->peer.transport_addr_list,
954 transports) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700955
956 if (transport == active)
Xufeng Zhang2317f442013-03-07 21:39:37 +0000957 continue;
Robert P. J. Day9dbc15f02008-04-12 18:54:24 -0700958 list_for_each_entry(chunk, &transport->transmitted,
959 transmitted_list) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700960 if (key == chunk->subh.data_hdr->tsn) {
961 match = transport;
962 goto out;
963 }
964 }
965 }
966out:
967 return match;
968}
969
Linus Torvalds1da177e2005-04-16 15:20:36 -0700970/* Do delayed input processing. This is scheduled by sctp_rcv(). */
David Howellsc4028952006-11-22 14:57:56 +0000971static void sctp_assoc_bh_rcv(struct work_struct *work)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700972{
David Howellsc4028952006-11-22 14:57:56 +0000973 struct sctp_association *asoc =
974 container_of(work, struct sctp_association,
975 base.inqueue.immediate);
Xin Long4e7696d2019-12-09 13:45:18 +0800976 struct net *net = asoc->base.net;
Xin Longbfc6f822017-08-05 20:00:04 +0800977 union sctp_subtype subtype;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700978 struct sctp_endpoint *ep;
979 struct sctp_chunk *chunk;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700980 struct sctp_inq *inqueue;
Xin Long59d8d442018-05-05 14:59:47 +0800981 int first_time = 1; /* is this the first time through the loop */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700982 int error = 0;
Xin Long59d8d442018-05-05 14:59:47 +0800983 int state;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700984
985 /* The association should be held so we should be safe. */
986 ep = asoc->ep;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700987
988 inqueue = &asoc->base.inqueue;
989 sctp_association_hold(asoc);
990 while (NULL != (chunk = sctp_inq_pop(inqueue))) {
991 state = asoc->state;
992 subtype = SCTP_ST_CHUNK(chunk->chunk_hdr->type);
993
Xin Long59d8d442018-05-05 14:59:47 +0800994 /* If the first chunk in the packet is AUTH, do special
995 * processing specified in Section 6.3 of SCTP-AUTH spec
996 */
997 if (first_time && subtype.chunk == SCTP_CID_AUTH) {
998 struct sctp_chunkhdr *next_hdr;
999
1000 next_hdr = sctp_inq_peek(inqueue);
1001 if (!next_hdr)
1002 goto normal;
1003
1004 /* If the next chunk is COOKIE-ECHO, skip the AUTH
1005 * chunk while saving a pointer to it so we can do
1006 * Authentication later (during cookie-echo
1007 * processing).
1008 */
1009 if (next_hdr->type == SCTP_CID_COOKIE_ECHO) {
1010 chunk->auth_chunk = skb_clone(chunk->skb,
1011 GFP_ATOMIC);
1012 chunk->auth = 1;
1013 continue;
1014 }
1015 }
1016
1017normal:
Vlad Yasevichbbd0d592007-10-03 17:51:34 -07001018 /* SCTP-AUTH, Section 6.3:
1019 * The receiver has a list of chunk types which it expects
1020 * to be received only after an AUTH-chunk. This list has
1021 * been sent to the peer during the association setup. It
1022 * MUST silently discard these chunks if they are not placed
1023 * after an AUTH chunk in the packet.
1024 */
1025 if (sctp_auth_recv_cid(subtype.chunk, asoc) && !chunk->auth)
1026 continue;
1027
Linus Torvalds1da177e2005-04-16 15:20:36 -07001028 /* Remember where the last DATA chunk came from so we
1029 * know where to send the SACK.
1030 */
1031 if (sctp_chunk_is_data(chunk))
1032 asoc->peer.last_data_from = chunk->transport;
Michele Baldessari196d6752012-12-01 04:49:42 +00001033 else {
Eric W. Biederman55e26eb2012-08-07 07:25:24 +00001034 SCTP_INC_STATS(net, SCTP_MIB_INCTRLCHUNKS);
Michele Baldessari196d6752012-12-01 04:49:42 +00001035 asoc->stats.ictrlchunks++;
1036 if (chunk->chunk_hdr->type == SCTP_CID_SACK)
1037 asoc->stats.isacks++;
1038 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001039
1040 if (chunk->transport)
Daniel Borkmanne5752352014-06-11 18:19:30 +02001041 chunk->transport->last_time_heard = ktime_get();
Linus Torvalds1da177e2005-04-16 15:20:36 -07001042
1043 /* Run through the state machine. */
Eric W. Biederman55e26eb2012-08-07 07:25:24 +00001044 error = sctp_do_sm(net, SCTP_EVENT_T_CHUNK, subtype,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001045 state, ep, asoc, chunk, GFP_ATOMIC);
1046
1047 /* Check to see if the association is freed in response to
1048 * the incoming chunk. If so, get out of the while loop.
1049 */
1050 if (asoc->base.dead)
1051 break;
1052
1053 /* If there is an error on chunk, discard this packet. */
1054 if (error && chunk)
1055 chunk->pdiscard = 1;
Xin Long59d8d442018-05-05 14:59:47 +08001056
1057 if (first_time)
1058 first_time = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001059 }
1060 sctp_association_put(asoc);
1061}
1062
1063/* This routine moves an association from its old sk to a new sk. */
1064void sctp_assoc_migrate(struct sctp_association *assoc, struct sock *newsk)
1065{
1066 struct sctp_sock *newsp = sctp_sk(newsk);
1067 struct sock *oldsk = assoc->base.sk;
1068
1069 /* Delete the association from the old endpoint's list of
1070 * associations.
1071 */
1072 list_del_init(&assoc->asocs);
1073
1074 /* Decrement the backlog value for a TCP-style socket. */
1075 if (sctp_style(oldsk, TCP))
Eric Dumazet7976a112019-11-05 14:11:52 -08001076 sk_acceptq_removed(oldsk);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001077
1078 /* Release references to the old endpoint and the sock. */
1079 sctp_endpoint_put(assoc->ep);
1080 sock_put(assoc->base.sk);
1081
1082 /* Get a reference to the new endpoint. */
1083 assoc->ep = newsp->ep;
1084 sctp_endpoint_hold(assoc->ep);
1085
1086 /* Get a reference to the new sock. */
1087 assoc->base.sk = newsk;
1088 sock_hold(assoc->base.sk);
1089
1090 /* Add the association to the new endpoint's list of associations. */
1091 sctp_endpoint_add_asoc(newsp->ep, assoc);
1092}
1093
1094/* Update an association (possibly from unexpected COOKIE-ECHO processing). */
Xin Long5ee8aa62017-06-20 16:05:11 +08001095int sctp_assoc_update(struct sctp_association *asoc,
1096 struct sctp_association *new)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001097{
1098 struct sctp_transport *trans;
1099 struct list_head *pos, *temp;
1100
1101 /* Copy in new parameters of peer. */
1102 asoc->c = new->c;
1103 asoc->peer.rwnd = new->peer.rwnd;
1104 asoc->peer.sack_needed = new->peer.sack_needed;
Daniel Borkmann1be9a952014-07-22 15:22:45 +02001105 asoc->peer.auth_capable = new->peer.auth_capable;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001106 asoc->peer.i = new->peer.i;
Xin Long5ee8aa62017-06-20 16:05:11 +08001107
1108 if (!sctp_tsnmap_init(&asoc->peer.tsn_map, SCTP_TSN_MAP_INITIAL,
1109 asoc->peer.i.initial_tsn, GFP_ATOMIC))
1110 return -ENOMEM;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001111
1112 /* Remove any peer addresses not present in the new association. */
1113 list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
1114 trans = list_entry(pos, struct sctp_transport, transports);
Vlad Yasevich0c427492010-04-28 08:47:19 +00001115 if (!sctp_assoc_lookup_paddr(new, &trans->ipaddr)) {
1116 sctp_assoc_rm_peer(asoc, trans);
1117 continue;
1118 }
Vlad Yasevich749bf922007-03-19 17:02:30 -07001119
1120 if (asoc->state >= SCTP_STATE_ESTABLISHED)
1121 sctp_transport_reset(trans);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001122 }
1123
1124 /* If the case is A (association restart), use
1125 * initial_tsn as next_tsn. If the case is B, use
1126 * current next_tsn in case data sent to peer
1127 * has been discarded and needs retransmission.
1128 */
1129 if (asoc->state >= SCTP_STATE_ESTABLISHED) {
1130 asoc->next_tsn = new->next_tsn;
1131 asoc->ctsn_ack_point = new->ctsn_ack_point;
1132 asoc->adv_peer_ack_point = new->adv_peer_ack_point;
1133
1134 /* Reinitialize SSN for both local streams
1135 * and peer's streams.
1136 */
Xin Longcee360a2017-05-31 16:36:31 +08001137 sctp_stream_clear(&asoc->stream);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001138
Vlad Yasevich0b58a812007-03-19 17:01:17 -07001139 /* Flush the ULP reassembly and ordered queue.
1140 * Any data there will now be stale and will
1141 * cause problems.
1142 */
1143 sctp_ulpq_flush(&asoc->ulpq);
1144
Vlad Yasevich749bf922007-03-19 17:02:30 -07001145 /* reset the overall association error count so
1146 * that the restarted association doesn't get torn
1147 * down on the next retransmission timer.
1148 */
1149 asoc->overall_error_count = 0;
1150
Linus Torvalds1da177e2005-04-16 15:20:36 -07001151 } else {
1152 /* Add any peer addresses from the new association. */
Robert P. J. Day9dbc15f02008-04-12 18:54:24 -07001153 list_for_each_entry(trans, &new->peer.transport_addr_list,
Xin Long5ee8aa62017-06-20 16:05:11 +08001154 transports)
1155 if (!sctp_assoc_lookup_paddr(asoc, &trans->ipaddr) &&
1156 !sctp_assoc_add_peer(asoc, &trans->ipaddr,
1157 GFP_ATOMIC, trans->state))
1158 return -ENOMEM;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001159
1160 asoc->ctsn_ack_point = asoc->next_tsn - 1;
1161 asoc->adv_peer_ack_point = asoc->ctsn_ack_point;
Xin Long3ab21372017-05-23 13:28:54 +08001162
Xin Longcee360a2017-05-31 16:36:31 +08001163 if (sctp_state(asoc, COOKIE_WAIT))
1164 sctp_stream_update(&asoc->stream, &new->stream);
Vlad Yasevich07d93962007-05-04 13:55:27 -07001165
Xin Long4abf5a62017-06-10 15:27:12 +08001166 /* get a new assoc id if we don't have one yet. */
Xin Long5ee8aa62017-06-20 16:05:11 +08001167 if (sctp_assoc_set_id(asoc, GFP_ATOMIC))
1168 return -ENOMEM;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001169 }
Vlad Yasevicha29a5bd2007-09-16 19:31:35 -07001170
wangweidong9d2c8812013-12-06 09:36:30 +08001171 /* SCTP-AUTH: Save the peer parameters from the new associations
Vlad Yasevich730fc3d2007-09-16 19:32:11 -07001172 * and also move the association shared keys over
1173 */
1174 kfree(asoc->peer.peer_random);
1175 asoc->peer.peer_random = new->peer.peer_random;
1176 new->peer.peer_random = NULL;
1177
1178 kfree(asoc->peer.peer_chunks);
1179 asoc->peer.peer_chunks = new->peer.peer_chunks;
1180 new->peer.peer_chunks = NULL;
1181
1182 kfree(asoc->peer.peer_hmacs);
1183 asoc->peer.peer_hmacs = new->peer.peer_hmacs;
1184 new->peer.peer_hmacs = NULL;
1185
Xin Long5ee8aa62017-06-20 16:05:11 +08001186 return sctp_auth_asoc_init_active_key(asoc, GFP_ATOMIC);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001187}
1188
1189/* Update the retran path for sending a retransmitted packet.
Daniel Borkmann4c47af42014-02-20 20:51:06 +01001190 * See also RFC4960, 6.4. Multi-Homed SCTP Endpoints:
1191 *
1192 * When there is outbound data to send and the primary path
1193 * becomes inactive (e.g., due to failures), or where the
1194 * SCTP user explicitly requests to send data to an
1195 * inactive destination transport address, before reporting
1196 * an error to its ULP, the SCTP endpoint should try to send
1197 * the data to an alternate active destination transport
1198 * address if one exists.
1199 *
1200 * When retransmitting data that timed out, if the endpoint
1201 * is multihomed, it should consider each source-destination
1202 * address pair in its retransmission selection policy.
1203 * When retransmitting timed-out data, the endpoint should
1204 * attempt to pick the most divergent source-destination
1205 * pair from the original source-destination pair to which
1206 * the packet was transmitted.
1207 *
1208 * Note: Rules for picking the most divergent source-destination
1209 * pair are an implementation decision and are not specified
1210 * within this document.
1211 *
1212 * Our basic strategy is to round-robin transports in priorities
Denys Vlasenko2103d6b2015-09-28 14:34:04 +02001213 * according to sctp_trans_score() e.g., if no such
Daniel Borkmann4c47af42014-02-20 20:51:06 +01001214 * transport with state SCTP_ACTIVE exists, round-robin through
1215 * SCTP_UNKNOWN, etc. You get the picture.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001216 */
Daniel Borkmann4c47af42014-02-20 20:51:06 +01001217static u8 sctp_trans_score(const struct sctp_transport *trans)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001218{
Denys Vlasenko2103d6b2015-09-28 14:34:04 +02001219 switch (trans->state) {
1220 case SCTP_ACTIVE:
1221 return 3; /* best case */
1222 case SCTP_UNKNOWN:
1223 return 2;
1224 case SCTP_PF:
1225 return 1;
1226 default: /* case SCTP_INACTIVE */
1227 return 0; /* worst case */
1228 }
Frank Filz3f7a87d2005-06-20 13:14:57 -07001229}
1230
Daniel Borkmanna7288c42014-06-11 18:19:31 +02001231static struct sctp_transport *sctp_trans_elect_tie(struct sctp_transport *trans1,
1232 struct sctp_transport *trans2)
1233{
1234 if (trans1->error_count > trans2->error_count) {
1235 return trans2;
1236 } else if (trans1->error_count == trans2->error_count &&
1237 ktime_after(trans2->last_time_heard,
1238 trans1->last_time_heard)) {
1239 return trans2;
1240 } else {
1241 return trans1;
1242 }
1243}
1244
Daniel Borkmann4c47af42014-02-20 20:51:06 +01001245static struct sctp_transport *sctp_trans_elect_best(struct sctp_transport *curr,
1246 struct sctp_transport *best)
1247{
Daniel Borkmanna7288c42014-06-11 18:19:31 +02001248 u8 score_curr, score_best;
1249
Daniel Borkmannea4f19c2014-08-22 13:03:29 +02001250 if (best == NULL || curr == best)
Daniel Borkmann4c47af42014-02-20 20:51:06 +01001251 return curr;
1252
Daniel Borkmanna7288c42014-06-11 18:19:31 +02001253 score_curr = sctp_trans_score(curr);
1254 score_best = sctp_trans_score(best);
1255
1256 /* First, try a score-based selection if both transport states
1257 * differ. If we're in a tie, lets try to make a more clever
1258 * decision here based on error counts and last time heard.
1259 */
1260 if (score_curr > score_best)
1261 return curr;
1262 else if (score_curr == score_best)
Xin Long39d2ade2016-03-10 15:31:57 +08001263 return sctp_trans_elect_tie(best, curr);
Daniel Borkmanna7288c42014-06-11 18:19:31 +02001264 else
1265 return best;
Daniel Borkmann4c47af42014-02-20 20:51:06 +01001266}
1267
1268void sctp_assoc_update_retran_path(struct sctp_association *asoc)
1269{
1270 struct sctp_transport *trans = asoc->peer.retran_path;
1271 struct sctp_transport *trans_next = NULL;
1272
1273 /* We're done as we only have the one and only path. */
1274 if (asoc->peer.transport_count == 1)
1275 return;
1276 /* If active_path and retran_path are the same and active,
1277 * then this is the only active path. Use it.
1278 */
1279 if (asoc->peer.active_path == asoc->peer.retran_path &&
1280 asoc->peer.active_path->state == SCTP_ACTIVE)
1281 return;
1282
1283 /* Iterate from retran_path's successor back to retran_path. */
1284 for (trans = list_next_entry(trans, transports); 1;
1285 trans = list_next_entry(trans, transports)) {
1286 /* Manually skip the head element. */
1287 if (&trans->transports == &asoc->peer.transport_addr_list)
1288 continue;
1289 if (trans->state == SCTP_UNCONFIRMED)
1290 continue;
1291 trans_next = sctp_trans_elect_best(trans, trans_next);
1292 /* Active is good enough for immediate return. */
1293 if (trans_next->state == SCTP_ACTIVE)
1294 break;
1295 /* We've reached the end, time to update path. */
1296 if (trans == asoc->peer.retran_path)
1297 break;
1298 }
1299
Daniel Borkmann433131b2014-03-13 14:45:26 +01001300 asoc->peer.retran_path = trans_next;
Daniel Borkmann4c47af42014-02-20 20:51:06 +01001301
1302 pr_debug("%s: association:%p updated new path to addr:%pISpc\n",
1303 __func__, asoc, &asoc->peer.retran_path->ipaddr.sa);
1304}
1305
Daniel Borkmannb82e8f32014-06-11 18:19:29 +02001306static void sctp_select_active_and_retran_path(struct sctp_association *asoc)
1307{
1308 struct sctp_transport *trans, *trans_pri = NULL, *trans_sec = NULL;
Daniel Borkmanna7288c42014-06-11 18:19:31 +02001309 struct sctp_transport *trans_pf = NULL;
Daniel Borkmannb82e8f32014-06-11 18:19:29 +02001310
1311 /* Look for the two most recently used active transports. */
1312 list_for_each_entry(trans, &asoc->peer.transport_addr_list,
1313 transports) {
Daniel Borkmanna7288c42014-06-11 18:19:31 +02001314 /* Skip uninteresting transports. */
Daniel Borkmannb82e8f32014-06-11 18:19:29 +02001315 if (trans->state == SCTP_INACTIVE ||
Daniel Borkmanna7288c42014-06-11 18:19:31 +02001316 trans->state == SCTP_UNCONFIRMED)
Daniel Borkmannb82e8f32014-06-11 18:19:29 +02001317 continue;
Daniel Borkmanna7288c42014-06-11 18:19:31 +02001318 /* Keep track of the best PF transport from our
1319 * list in case we don't find an active one.
1320 */
1321 if (trans->state == SCTP_PF) {
1322 trans_pf = sctp_trans_elect_best(trans, trans_pf);
1323 continue;
1324 }
1325 /* For active transports, pick the most recent ones. */
Daniel Borkmannb82e8f32014-06-11 18:19:29 +02001326 if (trans_pri == NULL ||
Daniel Borkmanne5752352014-06-11 18:19:30 +02001327 ktime_after(trans->last_time_heard,
1328 trans_pri->last_time_heard)) {
Daniel Borkmannb82e8f32014-06-11 18:19:29 +02001329 trans_sec = trans_pri;
1330 trans_pri = trans;
1331 } else if (trans_sec == NULL ||
Daniel Borkmanne5752352014-06-11 18:19:30 +02001332 ktime_after(trans->last_time_heard,
1333 trans_sec->last_time_heard)) {
Daniel Borkmannb82e8f32014-06-11 18:19:29 +02001334 trans_sec = trans;
1335 }
1336 }
1337
1338 /* RFC 2960 6.4 Multi-Homed SCTP Endpoints
1339 *
1340 * By default, an endpoint should always transmit to the primary
1341 * path, unless the SCTP user explicitly specifies the
1342 * destination transport address (and possibly source transport
1343 * address) to use. [If the primary is active but not most recent,
1344 * bump the most recently used transport.]
1345 */
1346 if ((asoc->peer.primary_path->state == SCTP_ACTIVE ||
1347 asoc->peer.primary_path->state == SCTP_UNKNOWN) &&
1348 asoc->peer.primary_path != trans_pri) {
1349 trans_sec = trans_pri;
1350 trans_pri = asoc->peer.primary_path;
1351 }
1352
1353 /* We did not find anything useful for a possible retransmission
1354 * path; either primary path that we found is the the same as
1355 * the current one, or we didn't generally find an active one.
1356 */
1357 if (trans_sec == NULL)
1358 trans_sec = trans_pri;
1359
1360 /* If we failed to find a usable transport, just camp on the
Daniel Borkmannaa4a83e2014-08-22 13:03:30 +02001361 * active or pick a PF iff it's the better choice.
Daniel Borkmannb82e8f32014-06-11 18:19:29 +02001362 */
1363 if (trans_pri == NULL) {
Daniel Borkmannaa4a83e2014-08-22 13:03:30 +02001364 trans_pri = sctp_trans_elect_best(asoc->peer.active_path, trans_pf);
1365 trans_sec = trans_pri;
Daniel Borkmannb82e8f32014-06-11 18:19:29 +02001366 }
1367
1368 /* Set the active and retran transports. */
1369 asoc->peer.active_path = trans_pri;
1370 asoc->peer.retran_path = trans_sec;
1371}
1372
Daniel Borkmann4c47af42014-02-20 20:51:06 +01001373struct sctp_transport *
1374sctp_assoc_choose_alter_transport(struct sctp_association *asoc,
1375 struct sctp_transport *last_sent_to)
Frank Filz3f7a87d2005-06-20 13:14:57 -07001376{
Wei Yongjun9919b452009-05-12 21:52:51 +08001377 /* If this is the first time packet is sent, use the active path,
1378 * else use the retran path. If the last packet was sent over the
Frank Filz3f7a87d2005-06-20 13:14:57 -07001379 * retran path, update the retran path and use it.
1380 */
Daniel Borkmann4c47af42014-02-20 20:51:06 +01001381 if (last_sent_to == NULL) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001382 return asoc->peer.active_path;
Daniel Borkmann4c47af42014-02-20 20:51:06 +01001383 } else {
Wei Yongjun9919b452009-05-12 21:52:51 +08001384 if (last_sent_to == asoc->peer.retran_path)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001385 sctp_assoc_update_retran_path(asoc);
Daniel Borkmann4c47af42014-02-20 20:51:06 +01001386
Linus Torvalds1da177e2005-04-16 15:20:36 -07001387 return asoc->peer.retran_path;
1388 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001389}
1390
Marcelo Ricardo Leitner2f5e3c92018-04-26 16:58:55 -03001391void sctp_assoc_update_frag_point(struct sctp_association *asoc)
1392{
1393 int frag = sctp_mtu_payload(sctp_sk(asoc->base.sk), asoc->pathmtu,
1394 sctp_datachk_len(&asoc->stream));
1395
1396 if (asoc->user_frag)
1397 frag = min_t(int, frag, asoc->user_frag);
1398
1399 frag = min_t(int, frag, SCTP_MAX_CHUNK_LEN -
1400 sctp_datachk_len(&asoc->stream));
1401
1402 asoc->frag_point = SCTP_TRUNC4(frag);
1403}
1404
Marcelo Ricardo Leitnerc4b28932018-04-26 16:58:53 -03001405void sctp_assoc_set_pmtu(struct sctp_association *asoc, __u32 pmtu)
1406{
Marcelo Ricardo Leitner2f5e3c92018-04-26 16:58:55 -03001407 if (asoc->pathmtu != pmtu) {
Marcelo Ricardo Leitnerc4b28932018-04-26 16:58:53 -03001408 asoc->pathmtu = pmtu;
Marcelo Ricardo Leitner2f5e3c92018-04-26 16:58:55 -03001409 sctp_assoc_update_frag_point(asoc);
1410 }
Marcelo Ricardo Leitnerc4b28932018-04-26 16:58:53 -03001411
1412 pr_debug("%s: asoc:%p, pmtu:%d, frag_point:%d\n", __func__, asoc,
1413 asoc->pathmtu, asoc->frag_point);
1414}
1415
Linus Torvalds1da177e2005-04-16 15:20:36 -07001416/* Update the association's pmtu and frag_point by going through all the
1417 * transports. This routine is called when a transport's PMTU has changed.
1418 */
Xin Long3ebfdf02017-04-04 13:39:55 +08001419void sctp_assoc_sync_pmtu(struct sctp_association *asoc)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001420{
1421 struct sctp_transport *t;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001422 __u32 pmtu = 0;
1423
1424 if (!asoc)
1425 return;
1426
1427 /* Get the lowest pmtu of all the transports. */
Marcelo Ricardo Leitner6ff0f872018-04-26 16:58:57 -03001428 list_for_each_entry(t, &asoc->peer.transport_addr_list, transports) {
Vlad Yasevich8a479492007-06-07 14:21:05 -04001429 if (t->pmtu_pending && t->dst) {
Xin Longd8053972018-10-15 19:58:29 +08001430 sctp_transport_update_pmtu(t,
1431 atomic_read(&t->mtu_info));
Vlad Yasevich8a479492007-06-07 14:21:05 -04001432 t->pmtu_pending = 0;
1433 }
Frank Filz52ccb8e2005-12-22 11:36:46 -08001434 if (!pmtu || (t->pathmtu < pmtu))
1435 pmtu = t->pathmtu;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001436 }
1437
Marcelo Ricardo Leitnerc4b28932018-04-26 16:58:53 -03001438 sctp_assoc_set_pmtu(asoc, pmtu);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001439}
1440
1441/* Should we send a SACK to update our peer? */
wangweidongce4a03d2013-12-06 09:36:29 +08001442static inline bool sctp_peer_needs_update(struct sctp_association *asoc)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001443{
Xin Long4e7696d2019-12-09 13:45:18 +08001444 struct net *net = asoc->base.net;
1445
Linus Torvalds1da177e2005-04-16 15:20:36 -07001446 switch (asoc->state) {
1447 case SCTP_STATE_ESTABLISHED:
1448 case SCTP_STATE_SHUTDOWN_PENDING:
1449 case SCTP_STATE_SHUTDOWN_RECEIVED:
1450 case SCTP_STATE_SHUTDOWN_SENT:
1451 if ((asoc->rwnd > asoc->a_rwnd) &&
Vlad Yasevich90f2f532009-11-23 15:53:57 -05001452 ((asoc->rwnd - asoc->a_rwnd) >= max_t(__u32,
Eric W. Biedermane1fc3b12012-08-07 07:29:57 +00001453 (asoc->base.sk->sk_rcvbuf >> net->sctp.rwnd_upd_shift),
Vlad Yasevich90f2f532009-11-23 15:53:57 -05001454 asoc->pathmtu)))
wangweidongce4a03d2013-12-06 09:36:29 +08001455 return true;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001456 break;
1457 default:
1458 break;
1459 }
wangweidongce4a03d2013-12-06 09:36:29 +08001460 return false;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001461}
1462
Daniel Borkmann362d5202014-04-14 21:45:17 +02001463/* Increase asoc's rwnd by len and send any window update SACK if needed. */
1464void sctp_assoc_rwnd_increase(struct sctp_association *asoc, unsigned int len)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001465{
1466 struct sctp_chunk *sack;
1467 struct timer_list *timer;
1468
Daniel Borkmann362d5202014-04-14 21:45:17 +02001469 if (asoc->rwnd_over) {
1470 if (asoc->rwnd_over >= len) {
1471 asoc->rwnd_over -= len;
1472 } else {
1473 asoc->rwnd += (len - asoc->rwnd_over);
1474 asoc->rwnd_over = 0;
1475 }
1476 } else {
1477 asoc->rwnd += len;
1478 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001479
Daniel Borkmann362d5202014-04-14 21:45:17 +02001480 /* If we had window pressure, start recovering it
1481 * once our rwnd had reached the accumulated pressure
1482 * threshold. The idea is to recover slowly, but up
1483 * to the initial advertised window.
1484 */
Marcelo Ricardo Leitner16360982016-12-23 14:29:37 -02001485 if (asoc->rwnd_press) {
Daniel Borkmann362d5202014-04-14 21:45:17 +02001486 int change = min(asoc->pathmtu, asoc->rwnd_press);
1487 asoc->rwnd += change;
1488 asoc->rwnd_press -= change;
1489 }
Vlad Yasevich4d3c46e2009-09-04 18:20:59 -04001490
Daniel Borkmann362d5202014-04-14 21:45:17 +02001491 pr_debug("%s: asoc:%p rwnd increased by %d to (%u, %u) - %u\n",
1492 __func__, asoc, len, asoc->rwnd, asoc->rwnd_over,
1493 asoc->a_rwnd);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001494
1495 /* Send a window update SACK if the rwnd has increased by at least the
1496 * minimum of the association's PMTU and half of the receive buffer.
1497 * The algorithm used is similar to the one described in
1498 * Section 4.2.3.3 of RFC 1122.
1499 */
Daniel Borkmann362d5202014-04-14 21:45:17 +02001500 if (sctp_peer_needs_update(asoc)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001501 asoc->a_rwnd = asoc->rwnd;
Daniel Borkmannbb333812013-06-28 19:49:40 +02001502
1503 pr_debug("%s: sending window update SACK- asoc:%p rwnd:%u "
1504 "a_rwnd:%u\n", __func__, asoc, asoc->rwnd,
1505 asoc->a_rwnd);
1506
Linus Torvalds1da177e2005-04-16 15:20:36 -07001507 sack = sctp_make_sack(asoc);
1508 if (!sack)
1509 return;
1510
1511 asoc->peer.sack_needed = 0;
1512
Marcelo Ricardo Leitnercea87682016-03-10 18:33:07 -03001513 sctp_outq_tail(&asoc->outqueue, sack, GFP_ATOMIC);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001514
1515 /* Stop the SACK timer. */
1516 timer = &asoc->timers[SCTP_EVENT_TIMEOUT_SACK];
Ying Xue25cc4ae92013-02-03 20:32:57 +00001517 if (del_timer(timer))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001518 sctp_association_put(asoc);
1519 }
1520}
1521
Daniel Borkmann362d5202014-04-14 21:45:17 +02001522/* Decrease asoc's rwnd by len. */
1523void sctp_assoc_rwnd_decrease(struct sctp_association *asoc, unsigned int len)
1524{
1525 int rx_count;
1526 int over = 0;
1527
1528 if (unlikely(!asoc->rwnd || asoc->rwnd_over))
1529 pr_debug("%s: association:%p has asoc->rwnd:%u, "
1530 "asoc->rwnd_over:%u!\n", __func__, asoc,
1531 asoc->rwnd, asoc->rwnd_over);
1532
1533 if (asoc->ep->rcvbuf_policy)
1534 rx_count = atomic_read(&asoc->rmem_alloc);
1535 else
1536 rx_count = atomic_read(&asoc->base.sk->sk_rmem_alloc);
1537
1538 /* If we've reached or overflowed our receive buffer, announce
1539 * a 0 rwnd if rwnd would still be positive. Store the
1540 * the potential pressure overflow so that the window can be restored
1541 * back to original value.
1542 */
1543 if (rx_count >= asoc->base.sk->sk_rcvbuf)
1544 over = 1;
1545
1546 if (asoc->rwnd >= len) {
1547 asoc->rwnd -= len;
1548 if (over) {
1549 asoc->rwnd_press += asoc->rwnd;
1550 asoc->rwnd = 0;
1551 }
1552 } else {
Marcelo Ricardo Leitner58b94d82016-12-23 14:29:02 -02001553 asoc->rwnd_over += len - asoc->rwnd;
Daniel Borkmann362d5202014-04-14 21:45:17 +02001554 asoc->rwnd = 0;
1555 }
1556
1557 pr_debug("%s: asoc:%p rwnd decreased by %d to (%u, %u, %u)\n",
1558 __func__, asoc, len, asoc->rwnd, asoc->rwnd_over,
1559 asoc->rwnd_press);
1560}
Linus Torvalds1da177e2005-04-16 15:20:36 -07001561
1562/* Build the bind address list for the association based on info from the
1563 * local endpoint and the remote peer.
1564 */
Alexey Dobriyan3182cd82005-07-11 20:57:47 -07001565int sctp_assoc_set_bind_addr_from_ep(struct sctp_association *asoc,
Xin Long1c662012017-08-05 19:59:54 +08001566 enum sctp_scope scope, gfp_t gfp)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001567{
Linus Torvalds1da177e2005-04-16 15:20:36 -07001568 int flags;
1569
1570 /* Use scoping rules to determine the subset of addresses from
1571 * the endpoint.
1572 */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001573 flags = (PF_INET6 == asoc->base.sk->sk_family) ? SCTP_ADDR6_ALLOWED : 0;
1574 if (asoc->peer.ipv4_address)
1575 flags |= SCTP_ADDR4_PEERSUPP;
1576 if (asoc->peer.ipv6_address)
1577 flags |= SCTP_ADDR6_PEERSUPP;
1578
Xin Long4e7696d2019-12-09 13:45:18 +08001579 return sctp_bind_addr_copy(asoc->base.net,
Eric W. Biederman4db67e82012-08-06 08:42:04 +00001580 &asoc->base.bind_addr,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001581 &asoc->ep->base.bind_addr,
1582 scope, gfp, flags);
1583}
1584
1585/* Build the association's bind address list from the cookie. */
1586int sctp_assoc_set_bind_addr_from_cookie(struct sctp_association *asoc,
Alexey Dobriyan3182cd82005-07-11 20:57:47 -07001587 struct sctp_cookie *cookie,
Al Virodd0fc662005-10-07 07:46:04 +01001588 gfp_t gfp)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001589{
1590 int var_size2 = ntohs(cookie->peer_init->chunk_hdr.length);
1591 int var_size3 = cookie->raw_addr_list_len;
1592 __u8 *raw = (__u8 *)cookie->peer_init + var_size2;
1593
1594 return sctp_raw_to_bind_addrs(&asoc->base.bind_addr, raw, var_size3,
1595 asoc->ep->base.bind_addr.port, gfp);
1596}
1597
YOSHIFUJI Hideakid808ad92007-02-09 23:25:18 +09001598/* Lookup laddr in the bind address list of an association. */
1599int sctp_assoc_lookup_laddr(struct sctp_association *asoc,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001600 const union sctp_addr *laddr)
1601{
Vlad Yasevich559cf712007-09-16 16:03:28 -07001602 int found = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001603
Linus Torvalds1da177e2005-04-16 15:20:36 -07001604 if ((asoc->base.bind_addr.port == ntohs(laddr->v4.sin_port)) &&
1605 sctp_bind_addr_match(&asoc->base.bind_addr, laddr,
Vlad Yasevich559cf712007-09-16 16:03:28 -07001606 sctp_sk(asoc->base.sk)))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001607 found = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001608
Linus Torvalds1da177e2005-04-16 15:20:36 -07001609 return found;
1610}
Vlad Yasevich07d93962007-05-04 13:55:27 -07001611
1612/* Set an association id for a given association */
1613int sctp_assoc_set_id(struct sctp_association *asoc, gfp_t gfp)
1614{
Mel Gormand0164ad2015-11-06 16:28:21 -08001615 bool preload = gfpflags_allow_blocking(gfp);
Tejun Heo94960e82013-02-27 17:05:00 -08001616 int ret;
Vlad Yasevichc6ba68a2009-06-01 12:41:15 -04001617
1618 /* If the id is already assigned, keep it. */
1619 if (asoc->assoc_id)
Tejun Heo94960e82013-02-27 17:05:00 -08001620 return 0;
Vlad Yasevich07d93962007-05-04 13:55:27 -07001621
Tejun Heo94960e82013-02-27 17:05:00 -08001622 if (preload)
1623 idr_preload(gfp);
Vlad Yasevich07d93962007-05-04 13:55:27 -07001624 spin_lock_bh(&sctp_assocs_id_lock);
Xin Long80df2702019-01-28 15:08:23 +08001625 /* 0, 1, 2 are used as SCTP_FUTURE_ASSOC, SCTP_CURRENT_ASSOC and
1626 * SCTP_ALL_ASSOC, so an available id must be > SCTP_ALL_ASSOC.
1627 */
1628 ret = idr_alloc_cyclic(&sctp_assocs_id, asoc, SCTP_ALL_ASSOC + 1, 0,
1629 GFP_NOWAIT);
Vlad Yasevich07d93962007-05-04 13:55:27 -07001630 spin_unlock_bh(&sctp_assocs_id_lock);
Tejun Heo94960e82013-02-27 17:05:00 -08001631 if (preload)
1632 idr_preload_end();
1633 if (ret < 0)
1634 return ret;
Vlad Yasevich07d93962007-05-04 13:55:27 -07001635
Tejun Heo94960e82013-02-27 17:05:00 -08001636 asoc->assoc_id = (sctp_assoc_t)ret;
1637 return 0;
Vlad Yasevich07d93962007-05-04 13:55:27 -07001638}
Vlad Yasevicha08de642007-12-20 14:11:47 -08001639
Wei Yongjun8b4472c2011-05-24 21:48:02 +00001640/* Free the ASCONF queue */
1641static void sctp_assoc_free_asconf_queue(struct sctp_association *asoc)
1642{
1643 struct sctp_chunk *asconf;
1644 struct sctp_chunk *tmp;
1645
1646 list_for_each_entry_safe(asconf, tmp, &asoc->addip_chunk_list, list) {
1647 list_del_init(&asconf->list);
1648 sctp_chunk_free(asconf);
1649 }
1650}
1651
Vlad Yasevicha08de642007-12-20 14:11:47 -08001652/* Free asconf_ack cache */
1653static void sctp_assoc_free_asconf_acks(struct sctp_association *asoc)
1654{
1655 struct sctp_chunk *ack;
1656 struct sctp_chunk *tmp;
1657
1658 list_for_each_entry_safe(ack, tmp, &asoc->asconf_ack_list,
1659 transmitted_list) {
1660 list_del_init(&ack->transmitted_list);
1661 sctp_chunk_free(ack);
1662 }
1663}
1664
1665/* Clean up the ASCONF_ACK queue */
1666void sctp_assoc_clean_asconf_ack_cache(const struct sctp_association *asoc)
1667{
1668 struct sctp_chunk *ack;
1669 struct sctp_chunk *tmp;
1670
Lucas De Marchi25985ed2011-03-30 22:57:33 -03001671 /* We can remove all the entries from the queue up to
Vlad Yasevicha08de642007-12-20 14:11:47 -08001672 * the "Peer-Sequence-Number".
1673 */
1674 list_for_each_entry_safe(ack, tmp, &asoc->asconf_ack_list,
1675 transmitted_list) {
1676 if (ack->subh.addip_hdr->serial ==
1677 htonl(asoc->peer.addip_serial))
1678 break;
1679
1680 list_del_init(&ack->transmitted_list);
1681 sctp_chunk_free(ack);
1682 }
1683}
1684
1685/* Find the ASCONF_ACK whose serial number matches ASCONF */
1686struct sctp_chunk *sctp_assoc_lookup_asconf_ack(
1687 const struct sctp_association *asoc,
1688 __be32 serial)
1689{
Wei Yongjuna8699812008-02-05 23:35:04 +09001690 struct sctp_chunk *ack;
Vlad Yasevicha08de642007-12-20 14:11:47 -08001691
1692 /* Walk through the list of cached ASCONF-ACKs and find the
1693 * ack chunk whose serial number matches that of the request.
1694 */
1695 list_for_each_entry(ack, &asoc->asconf_ack_list, transmitted_list) {
Daniel Borkmannb69040d2014-10-09 22:55:32 +02001696 if (sctp_chunk_pending(ack))
1697 continue;
Vlad Yasevicha08de642007-12-20 14:11:47 -08001698 if (ack->subh.addip_hdr->serial == serial) {
1699 sctp_chunk_hold(ack);
Wei Yongjuna8699812008-02-05 23:35:04 +09001700 return ack;
Vlad Yasevicha08de642007-12-20 14:11:47 -08001701 }
1702 }
1703
Wei Yongjuna8699812008-02-05 23:35:04 +09001704 return NULL;
Vlad Yasevicha08de642007-12-20 14:11:47 -08001705}
Wei Yongjuna000c012011-05-29 23:23:36 +00001706
1707void sctp_asconf_queue_teardown(struct sctp_association *asoc)
1708{
1709 /* Free any cached ASCONF_ACK chunk. */
1710 sctp_assoc_free_asconf_acks(asoc);
1711
1712 /* Free the ASCONF queue. */
1713 sctp_assoc_free_asconf_queue(asoc);
1714
1715 /* Free any cached ASCONF chunk. */
1716 if (asoc->addip_last_asconf)
1717 sctp_chunk_free(asoc->addip_last_asconf);
1718}