Commit | Line | Data |
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60c778b2 | 1 | /* SCTP kernel implementation |
1da177e4 LT |
2 | * (C) Copyright IBM Corp. 2001, 2004 |
3 | * Copyright (c) 1999-2000 Cisco, Inc. | |
4 | * Copyright (c) 1999-2001 Motorola, Inc. | |
5 | * Copyright (c) 2001 Intel Corp. | |
6 | * Copyright (c) 2001 La Monte H.P. Yarroll | |
7 | * | |
60c778b2 | 8 | * This file is part of the SCTP kernel implementation |
1da177e4 LT |
9 | * |
10 | * This module provides the abstraction for an SCTP association. | |
11 | * | |
60c778b2 | 12 | * This SCTP implementation is free software; |
1da177e4 LT |
13 | * 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 | * | |
60c778b2 | 18 | * This SCTP implementation is distributed in the hope that it |
1da177e4 LT |
19 | * 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 | |
4b2f13a2 JK |
25 | * along with GNU CC; see the file COPYING. If not, see |
26 | * <http://www.gnu.org/licenses/>. | |
1da177e4 LT |
27 | * |
28 | * Please send any bug reports or fixes you make to the | |
29 | * email address(es): | |
91705c61 | 30 | * lksctp developers <linux-sctp@vger.kernel.org> |
1da177e4 | 31 | * |
1da177e4 LT |
32 | * Written or modified by: |
33 | * La Monte H.P. Yarroll <piggy@acm.org> | |
34 | * Karl Knutson <karl@athena.chicago.il.us> | |
35 | * Jon Grimm <jgrimm@us.ibm.com> | |
36 | * Xingang Guo <xingang.guo@intel.com> | |
37 | * Hui Huang <hui.huang@nokia.com> | |
38 | * Sridhar Samudrala <sri@us.ibm.com> | |
39 | * Daisy Chang <daisyc@us.ibm.com> | |
40 | * Ryan Layer <rmlayer@us.ibm.com> | |
41 | * Kevin Gao <kevin.gao@intel.com> | |
1da177e4 LT |
42 | */ |
43 | ||
145ce502 JP |
44 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
45 | ||
1da177e4 LT |
46 | #include <linux/types.h> |
47 | #include <linux/fcntl.h> | |
48 | #include <linux/poll.h> | |
49 | #include <linux/init.h> | |
1da177e4 LT |
50 | |
51 | #include <linux/slab.h> | |
52 | #include <linux/in.h> | |
53 | #include <net/ipv6.h> | |
54 | #include <net/sctp/sctp.h> | |
55 | #include <net/sctp/sm.h> | |
56 | ||
57 | /* Forward declarations for internal functions. */ | |
b82e8f31 | 58 | static void sctp_select_active_and_retran_path(struct sctp_association *asoc); |
c4028958 | 59 | static void sctp_assoc_bh_rcv(struct work_struct *work); |
a08de64d | 60 | static void sctp_assoc_free_asconf_acks(struct sctp_association *asoc); |
8b4472cc | 61 | static void sctp_assoc_free_asconf_queue(struct sctp_association *asoc); |
1da177e4 | 62 | |
1da177e4 LT |
63 | /* 1st Level Abstractions. */ |
64 | ||
65 | /* Initialize a new association from provided memory. */ | |
1c662018 XL |
66 | static struct sctp_association *sctp_association_init( |
67 | struct sctp_association *asoc, | |
68 | const struct sctp_endpoint *ep, | |
69 | const struct sock *sk, | |
70 | enum sctp_scope scope, gfp_t gfp) | |
1da177e4 | 71 | { |
e1fc3b14 | 72 | struct net *net = sock_net(sk); |
1da177e4 | 73 | struct sctp_sock *sp; |
3c918704 | 74 | struct sctp_paramhdr *p; |
58194778 | 75 | int i; |
1da177e4 LT |
76 | |
77 | /* Retrieve the SCTP per socket area. */ | |
78 | sp = sctp_sk((struct sock *)sk); | |
79 | ||
1da177e4 LT |
80 | /* Discarding const is appropriate here. */ |
81 | asoc->ep = (struct sctp_endpoint *)ep; | |
1da177e4 | 82 | asoc->base.sk = (struct sock *)sk; |
2e0c9e79 DB |
83 | |
84 | sctp_endpoint_hold(asoc->ep); | |
1da177e4 LT |
85 | sock_hold(asoc->base.sk); |
86 | ||
87 | /* Initialize the common base substructure. */ | |
88 | asoc->base.type = SCTP_EP_TYPE_ASSOCIATION; | |
89 | ||
90 | /* Initialize the object handling fields. */ | |
c638457a | 91 | refcount_set(&asoc->base.refcnt, 1); |
1da177e4 LT |
92 | |
93 | /* Initialize the bind addr area. */ | |
94 | sctp_bind_addr_init(&asoc->base.bind_addr, ep->base.bind_addr.port); | |
1da177e4 LT |
95 | |
96 | asoc->state = SCTP_STATE_CLOSED; | |
52db882f | 97 | asoc->cookie_life = ms_to_ktime(sp->assocparams.sasoc_cookie_life); |
f68b2e05 | 98 | asoc->user_frag = sp->user_frag; |
1da177e4 LT |
99 | |
100 | /* Set the association max_retrans and RTO values from the | |
101 | * socket values. | |
102 | */ | |
103 | asoc->max_retrans = sp->assocparams.sasoc_asocmaxrxt; | |
e1fc3b14 | 104 | asoc->pf_retrans = net->sctp.pf_retrans; |
5aa93bcf | 105 | |
1da177e4 LT |
106 | asoc->rto_initial = msecs_to_jiffies(sp->rtoinfo.srto_initial); |
107 | asoc->rto_max = msecs_to_jiffies(sp->rtoinfo.srto_max); | |
108 | asoc->rto_min = msecs_to_jiffies(sp->rtoinfo.srto_min); | |
109 | ||
52ccb8e9 FF |
110 | /* Initialize the association's heartbeat interval based on the |
111 | * sock configured value. | |
112 | */ | |
113 | asoc->hbinterval = msecs_to_jiffies(sp->hbinterval); | |
114 | ||
115 | /* Initialize path max retrans value. */ | |
116 | asoc->pathmaxrxt = sp->pathmaxrxt; | |
117 | ||
118 | /* Initialize default path MTU. */ | |
119 | asoc->pathmtu = sp->pathmtu; | |
120 | ||
121 | /* Set association default SACK delay */ | |
122 | asoc->sackdelay = msecs_to_jiffies(sp->sackdelay); | |
d364d927 | 123 | asoc->sackfreq = sp->sackfreq; |
52ccb8e9 FF |
124 | |
125 | /* Set the association default flags controlling | |
126 | * Heartbeat, SACK delay, and Path MTU Discovery. | |
127 | */ | |
128 | asoc->param_flags = sp->param_flags; | |
129 | ||
9d2c881a | 130 | /* Initialize the maximum number of new data packets that can be sent |
1da177e4 LT |
131 | * in a burst. |
132 | */ | |
70331571 | 133 | asoc->max_burst = sp->max_burst; |
1da177e4 | 134 | |
1e7d3d90 | 135 | /* initialize association timers */ |
1e7d3d90 VY |
136 | asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_COOKIE] = asoc->rto_initial; |
137 | asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_INIT] = asoc->rto_initial; | |
138 | asoc->timeouts[SCTP_EVENT_TIMEOUT_T2_SHUTDOWN] = asoc->rto_initial; | |
1e7d3d90 VY |
139 | |
140 | /* sctpimpguide Section 2.12.2 | |
141 | * If the 'T5-shutdown-guard' timer is used, it SHOULD be set to the | |
142 | * recommended value of 5 times 'RTO.Max'. | |
143 | */ | |
d808ad9a | 144 | asoc->timeouts[SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD] |
1e7d3d90 VY |
145 | = 5 * asoc->rto_max; |
146 | ||
52ccb8e9 | 147 | asoc->timeouts[SCTP_EVENT_TIMEOUT_SACK] = asoc->sackdelay; |
9f70f46b | 148 | asoc->timeouts[SCTP_EVENT_TIMEOUT_AUTOCLOSE] = sp->autoclose * HZ; |
d808ad9a | 149 | |
421f91d2 | 150 | /* Initializes the timers */ |
b24b8a24 PE |
151 | for (i = SCTP_EVENT_TIMEOUT_NONE; i < SCTP_NUM_TIMEOUT_TYPES; ++i) |
152 | setup_timer(&asoc->timers[i], sctp_timer_events[i], | |
153 | (unsigned long)asoc); | |
1da177e4 LT |
154 | |
155 | /* Pull default initialization values from the sock options. | |
156 | * Note: This assumes that the values have already been | |
157 | * validated in the sock. | |
158 | */ | |
159 | asoc->c.sinit_max_instreams = sp->initmsg.sinit_max_instreams; | |
160 | asoc->c.sinit_num_ostreams = sp->initmsg.sinit_num_ostreams; | |
161 | asoc->max_init_attempts = sp->initmsg.sinit_max_attempts; | |
162 | ||
163 | asoc->max_init_timeo = | |
164 | msecs_to_jiffies(sp->initmsg.sinit_max_init_timeo); | |
165 | ||
1da177e4 LT |
166 | /* Set the local window size for receive. |
167 | * This is also the rcvbuf space per association. | |
168 | * RFC 6 - A SCTP receiver MUST be able to receive a minimum of | |
169 | * 1500 bytes in one SCTP packet. | |
170 | */ | |
049b3ff5 | 171 | if ((sk->sk_rcvbuf/2) < SCTP_DEFAULT_MINWINDOW) |
1da177e4 LT |
172 | asoc->rwnd = SCTP_DEFAULT_MINWINDOW; |
173 | else | |
049b3ff5 | 174 | asoc->rwnd = sk->sk_rcvbuf/2; |
1da177e4 LT |
175 | |
176 | asoc->a_rwnd = asoc->rwnd; | |
177 | ||
1da177e4 LT |
178 | /* Use my own max window until I learn something better. */ |
179 | asoc->peer.rwnd = SCTP_DEFAULT_MAXWINDOW; | |
180 | ||
049b3ff5 NH |
181 | /* Initialize the receive memory counter */ |
182 | atomic_set(&asoc->rmem_alloc, 0); | |
183 | ||
1da177e4 LT |
184 | init_waitqueue_head(&asoc->wait); |
185 | ||
186 | asoc->c.my_vtag = sctp_generate_tag(ep); | |
1da177e4 LT |
187 | asoc->c.my_port = ep->base.bind_addr.port; |
188 | ||
189 | asoc->c.initial_tsn = sctp_generate_tsn(ep); | |
190 | ||
191 | asoc->next_tsn = asoc->c.initial_tsn; | |
192 | ||
193 | asoc->ctsn_ack_point = asoc->next_tsn - 1; | |
194 | asoc->adv_peer_ack_point = asoc->ctsn_ack_point; | |
195 | asoc->highest_sacked = asoc->ctsn_ack_point; | |
196 | asoc->last_cwr_tsn = asoc->ctsn_ack_point; | |
1da177e4 | 197 | |
1da177e4 LT |
198 | /* ADDIP Section 4.1 Asconf Chunk Procedures |
199 | * | |
200 | * When an endpoint has an ASCONF signaled change to be sent to the | |
201 | * remote endpoint it should do the following: | |
202 | * ... | |
203 | * A2) a serial number should be assigned to the chunk. The serial | |
204 | * number SHOULD be a monotonically increasing number. The serial | |
205 | * numbers SHOULD be initialized at the start of the | |
206 | * association to the same value as the initial TSN. | |
207 | */ | |
208 | asoc->addip_serial = asoc->c.initial_tsn; | |
cc16f00f | 209 | asoc->strreset_outseq = asoc->c.initial_tsn; |
1da177e4 | 210 | |
79af02c2 | 211 | INIT_LIST_HEAD(&asoc->addip_chunk_list); |
a08de64d | 212 | INIT_LIST_HEAD(&asoc->asconf_ack_list); |
1da177e4 LT |
213 | |
214 | /* Make an empty list of remote transport addresses. */ | |
215 | INIT_LIST_HEAD(&asoc->peer.transport_addr_list); | |
216 | ||
217 | /* RFC 2960 5.1 Normal Establishment of an Association | |
218 | * | |
219 | * After the reception of the first data chunk in an | |
220 | * association the endpoint must immediately respond with a | |
221 | * sack to acknowledge the data chunk. Subsequent | |
222 | * acknowledgements should be done as described in Section | |
223 | * 6.2. | |
224 | * | |
225 | * [We implement this by telling a new association that it | |
226 | * already received one packet.] | |
227 | */ | |
228 | asoc->peer.sack_needed = 1; | |
4244854d | 229 | asoc->peer.sack_generation = 1; |
1da177e4 | 230 | |
73d9c4fd VY |
231 | /* Assume that the peer will tell us if he recognizes ASCONF |
232 | * as part of INIT exchange. | |
9d2c881a | 233 | * The sctp_addip_noauth option is there for backward compatibility |
73d9c4fd | 234 | * and will revert old behavior. |
1da177e4 | 235 | */ |
e1fc3b14 | 236 | if (net->sctp.addip_noauth) |
73d9c4fd | 237 | asoc->peer.asconf_capable = 1; |
1da177e4 LT |
238 | |
239 | /* Create an input queue. */ | |
240 | sctp_inq_init(&asoc->base.inqueue); | |
c4028958 | 241 | sctp_inq_set_th_handler(&asoc->base.inqueue, sctp_assoc_bh_rcv); |
1da177e4 LT |
242 | |
243 | /* Create an output queue. */ | |
244 | sctp_outq_init(asoc, &asoc->outqueue); | |
245 | ||
246 | if (!sctp_ulpq_init(&asoc->ulpq, asoc)) | |
247 | goto fail_init; | |
248 | ||
ff356414 XL |
249 | if (sctp_stream_init(&asoc->stream, asoc->c.sinit_num_ostreams, |
250 | 0, gfp)) | |
3dbcc105 XL |
251 | goto fail_init; |
252 | ||
1da177e4 LT |
253 | /* Assume that peer would support both address types unless we are |
254 | * told otherwise. | |
255 | */ | |
256 | asoc->peer.ipv4_address = 1; | |
a2c39584 WY |
257 | if (asoc->base.sk->sk_family == PF_INET6) |
258 | asoc->peer.ipv6_address = 1; | |
1da177e4 LT |
259 | INIT_LIST_HEAD(&asoc->asocs); |
260 | ||
1da177e4 LT |
261 | asoc->default_stream = sp->default_stream; |
262 | asoc->default_ppid = sp->default_ppid; | |
263 | asoc->default_flags = sp->default_flags; | |
264 | asoc->default_context = sp->default_context; | |
265 | asoc->default_timetolive = sp->default_timetolive; | |
6ab792f5 | 266 | asoc->default_rcv_context = sp->default_rcv_context; |
1da177e4 | 267 | |
a29a5bd4 VY |
268 | /* AUTH related initializations */ |
269 | INIT_LIST_HEAD(&asoc->endpoint_shared_keys); | |
58194778 | 270 | if (sctp_auth_asoc_copy_shkeys(ep, asoc, gfp)) |
3dbcc105 | 271 | goto stream_free; |
a29a5bd4 VY |
272 | |
273 | asoc->active_key_id = ep->active_key_id; | |
28aa4c26 | 274 | asoc->prsctp_enable = ep->prsctp_enable; |
c28445c3 | 275 | asoc->reconf_enable = ep->reconf_enable; |
9fb657ae | 276 | asoc->strreset_enable = ep->strreset_enable; |
a29a5bd4 | 277 | |
a29a5bd4 VY |
278 | /* Save the hmacs and chunks list into this association */ |
279 | if (ep->auth_hmacs_list) | |
280 | memcpy(asoc->c.auth_hmacs, ep->auth_hmacs_list, | |
281 | ntohs(ep->auth_hmacs_list->param_hdr.length)); | |
282 | if (ep->auth_chunk_list) | |
283 | memcpy(asoc->c.auth_chunks, ep->auth_chunk_list, | |
284 | ntohs(ep->auth_chunk_list->param_hdr.length)); | |
285 | ||
286 | /* Get the AUTH random number for this association */ | |
3c918704 | 287 | p = (struct sctp_paramhdr *)asoc->c.auth_random; |
a29a5bd4 | 288 | p->type = SCTP_PARAM_RANDOM; |
3c918704 | 289 | p->length = htons(sizeof(*p) + SCTP_AUTH_RANDOM_LENGTH); |
a29a5bd4 VY |
290 | get_random_bytes(p+1, SCTP_AUTH_RANDOM_LENGTH); |
291 | ||
1da177e4 LT |
292 | return asoc; |
293 | ||
3dbcc105 | 294 | stream_free: |
cee360ab | 295 | sctp_stream_free(&asoc->stream); |
1da177e4 | 296 | fail_init: |
1da177e4 | 297 | sock_put(asoc->base.sk); |
2e0c9e79 | 298 | sctp_endpoint_put(asoc->ep); |
1da177e4 LT |
299 | return NULL; |
300 | } | |
301 | ||
302 | /* Allocate and initialize a new association */ | |
303 | struct sctp_association *sctp_association_new(const struct sctp_endpoint *ep, | |
1c662018 XL |
304 | const struct sock *sk, |
305 | enum sctp_scope scope, gfp_t gfp) | |
1da177e4 LT |
306 | { |
307 | struct sctp_association *asoc; | |
308 | ||
939cfa75 | 309 | asoc = kzalloc(sizeof(*asoc), gfp); |
1da177e4 LT |
310 | if (!asoc) |
311 | goto fail; | |
312 | ||
313 | if (!sctp_association_init(asoc, ep, sk, scope, gfp)) | |
314 | goto fail_init; | |
315 | ||
1da177e4 | 316 | SCTP_DBG_OBJCNT_INC(assoc); |
bb33381d DB |
317 | |
318 | pr_debug("Created asoc %p\n", asoc); | |
1da177e4 LT |
319 | |
320 | return asoc; | |
321 | ||
322 | fail_init: | |
323 | kfree(asoc); | |
324 | fail: | |
325 | return NULL; | |
326 | } | |
327 | ||
328 | /* Free this association if possible. There may still be users, so | |
329 | * the actual deallocation may be delayed. | |
330 | */ | |
331 | void sctp_association_free(struct sctp_association *asoc) | |
332 | { | |
333 | struct sock *sk = asoc->base.sk; | |
334 | struct sctp_transport *transport; | |
335 | struct list_head *pos, *temp; | |
336 | int i; | |
337 | ||
de76e695 VY |
338 | /* Only real associations count against the endpoint, so |
339 | * don't bother for if this is a temporary association. | |
340 | */ | |
d3217b15 | 341 | if (!list_empty(&asoc->asocs)) { |
de76e695 VY |
342 | list_del(&asoc->asocs); |
343 | ||
344 | /* Decrement the backlog value for a TCP-style listening | |
345 | * socket. | |
346 | */ | |
347 | if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING)) | |
348 | sk->sk_ack_backlog--; | |
349 | } | |
1da177e4 LT |
350 | |
351 | /* Mark as dead, so other users can know this structure is | |
352 | * going away. | |
353 | */ | |
0022d2dd | 354 | asoc->base.dead = true; |
1da177e4 LT |
355 | |
356 | /* Dispose of any data lying around in the outqueue. */ | |
357 | sctp_outq_free(&asoc->outqueue); | |
358 | ||
359 | /* Dispose of any pending messages for the upper layer. */ | |
360 | sctp_ulpq_free(&asoc->ulpq); | |
361 | ||
362 | /* Dispose of any pending chunks on the inqueue. */ | |
363 | sctp_inq_free(&asoc->base.inqueue); | |
364 | ||
8e1ee18c VY |
365 | sctp_tsnmap_free(&asoc->peer.tsn_map); |
366 | ||
a8386317 | 367 | /* Free stream information. */ |
cee360ab | 368 | sctp_stream_free(&asoc->stream); |
1da177e4 | 369 | |
7b9438de XL |
370 | if (asoc->strreset_chunk) |
371 | sctp_chunk_free(asoc->strreset_chunk); | |
372 | ||
1da177e4 LT |
373 | /* Clean up the bound address list. */ |
374 | sctp_bind_addr_free(&asoc->base.bind_addr); | |
375 | ||
376 | /* Do we need to go through all of our timers and | |
377 | * delete them? To be safe we will try to delete all, but we | |
378 | * should be able to go through and make a guess based | |
379 | * on our state. | |
380 | */ | |
381 | for (i = SCTP_EVENT_TIMEOUT_NONE; i < SCTP_NUM_TIMEOUT_TYPES; ++i) { | |
25cc4ae9 | 382 | if (del_timer(&asoc->timers[i])) |
1da177e4 LT |
383 | sctp_association_put(asoc); |
384 | } | |
385 | ||
386 | /* Free peer's cached cookie. */ | |
a51482bd | 387 | kfree(asoc->peer.cookie); |
730fc3d0 VY |
388 | kfree(asoc->peer.peer_random); |
389 | kfree(asoc->peer.peer_chunks); | |
390 | kfree(asoc->peer.peer_hmacs); | |
1da177e4 LT |
391 | |
392 | /* Release the transport structures. */ | |
393 | list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) { | |
394 | transport = list_entry(pos, struct sctp_transport, transports); | |
45122ca2 | 395 | list_del_rcu(pos); |
4f008781 | 396 | sctp_unhash_transport(transport); |
1da177e4 LT |
397 | sctp_transport_free(transport); |
398 | } | |
399 | ||
3f7a87d2 FF |
400 | asoc->peer.transport_count = 0; |
401 | ||
a000c01e | 402 | sctp_asconf_queue_teardown(asoc); |
1da177e4 | 403 | |
8a07eb0a | 404 | /* Free pending address space being deleted */ |
7d37d0c1 | 405 | kfree(asoc->asconf_addr_del_pending); |
8a07eb0a | 406 | |
a29a5bd4 VY |
407 | /* AUTH - Free the endpoint shared keys */ |
408 | sctp_auth_destroy_keys(&asoc->endpoint_shared_keys); | |
409 | ||
410 | /* AUTH - Free the association shared key */ | |
411 | sctp_auth_key_put(asoc->asoc_shared_key); | |
412 | ||
1da177e4 LT |
413 | sctp_association_put(asoc); |
414 | } | |
415 | ||
416 | /* Cleanup and free up an association. */ | |
417 | static void sctp_association_destroy(struct sctp_association *asoc) | |
418 | { | |
bb33381d DB |
419 | if (unlikely(!asoc->base.dead)) { |
420 | WARN(1, "Attempt to destroy undead association %p!\n", asoc); | |
421 | return; | |
422 | } | |
1da177e4 LT |
423 | |
424 | sctp_endpoint_put(asoc->ep); | |
425 | sock_put(asoc->base.sk); | |
426 | ||
427 | if (asoc->assoc_id != 0) { | |
428 | spin_lock_bh(&sctp_assocs_id_lock); | |
429 | idr_remove(&sctp_assocs_id, asoc->assoc_id); | |
430 | spin_unlock_bh(&sctp_assocs_id_lock); | |
431 | } | |
432 | ||
547b792c | 433 | WARN_ON(atomic_read(&asoc->rmem_alloc)); |
049b3ff5 | 434 | |
862b5ab9 | 435 | kfree_rcu(asoc, rcu); |
ff2266cd | 436 | SCTP_DBG_OBJCNT_DEC(assoc); |
1da177e4 LT |
437 | } |
438 | ||
439 | /* Change the primary destination address for the peer. */ | |
440 | void sctp_assoc_set_primary(struct sctp_association *asoc, | |
441 | struct sctp_transport *transport) | |
442 | { | |
319fa2a2 VY |
443 | int changeover = 0; |
444 | ||
445 | /* it's a changeover only if we already have a primary path | |
446 | * that we are changing | |
447 | */ | |
448 | if (asoc->peer.primary_path != NULL && | |
449 | asoc->peer.primary_path != transport) | |
450 | changeover = 1 ; | |
451 | ||
1da177e4 LT |
452 | asoc->peer.primary_path = transport; |
453 | ||
454 | /* Set a default msg_name for events. */ | |
455 | memcpy(&asoc->peer.primary_addr, &transport->ipaddr, | |
456 | sizeof(union sctp_addr)); | |
457 | ||
458 | /* If the primary path is changing, assume that the | |
459 | * user wants to use this new path. | |
460 | */ | |
ad8fec17 SS |
461 | if ((transport->state == SCTP_ACTIVE) || |
462 | (transport->state == SCTP_UNKNOWN)) | |
1da177e4 LT |
463 | asoc->peer.active_path = transport; |
464 | ||
465 | /* | |
466 | * SFR-CACC algorithm: | |
467 | * Upon the receipt of a request to change the primary | |
468 | * destination address, on the data structure for the new | |
469 | * primary destination, the sender MUST do the following: | |
470 | * | |
471 | * 1) If CHANGEOVER_ACTIVE is set, then there was a switch | |
472 | * to this destination address earlier. The sender MUST set | |
473 | * CYCLING_CHANGEOVER to indicate that this switch is a | |
474 | * double switch to the same destination address. | |
e0e9db17 VY |
475 | * |
476 | * Really, only bother is we have data queued or outstanding on | |
477 | * the association. | |
1da177e4 | 478 | */ |
e0e9db17 VY |
479 | if (!asoc->outqueue.outstanding_bytes && !asoc->outqueue.out_qlen) |
480 | return; | |
481 | ||
1da177e4 | 482 | if (transport->cacc.changeover_active) |
319fa2a2 | 483 | transport->cacc.cycling_changeover = changeover; |
1da177e4 LT |
484 | |
485 | /* 2) The sender MUST set CHANGEOVER_ACTIVE to indicate that | |
486 | * a changeover has occurred. | |
487 | */ | |
319fa2a2 | 488 | transport->cacc.changeover_active = changeover; |
1da177e4 LT |
489 | |
490 | /* 3) The sender MUST store the next TSN to be sent in | |
491 | * next_tsn_at_change. | |
492 | */ | |
493 | transport->cacc.next_tsn_at_change = asoc->next_tsn; | |
494 | } | |
495 | ||
3f7a87d2 FF |
496 | /* Remove a transport from an association. */ |
497 | void sctp_assoc_rm_peer(struct sctp_association *asoc, | |
498 | struct sctp_transport *peer) | |
499 | { | |
8376fdc9 XL |
500 | struct sctp_transport *transport; |
501 | struct list_head *pos; | |
502 | struct sctp_chunk *ch; | |
3f7a87d2 | 503 | |
bb33381d DB |
504 | pr_debug("%s: association:%p addr:%pISpc\n", |
505 | __func__, asoc, &peer->ipaddr.sa); | |
3f7a87d2 FF |
506 | |
507 | /* If we are to remove the current retran_path, update it | |
508 | * to the next peer before removing this peer from the list. | |
509 | */ | |
510 | if (asoc->peer.retran_path == peer) | |
511 | sctp_assoc_update_retran_path(asoc); | |
512 | ||
513 | /* Remove this peer from the list. */ | |
45122ca2 | 514 | list_del_rcu(&peer->transports); |
4f008781 XL |
515 | /* Remove this peer from the transport hashtable */ |
516 | sctp_unhash_transport(peer); | |
3f7a87d2 FF |
517 | |
518 | /* Get the first transport of asoc. */ | |
519 | pos = asoc->peer.transport_addr_list.next; | |
520 | transport = list_entry(pos, struct sctp_transport, transports); | |
521 | ||
522 | /* Update any entries that match the peer to be deleted. */ | |
523 | if (asoc->peer.primary_path == peer) | |
524 | sctp_assoc_set_primary(asoc, transport); | |
525 | if (asoc->peer.active_path == peer) | |
526 | asoc->peer.active_path = transport; | |
9494c7c5 WY |
527 | if (asoc->peer.retran_path == peer) |
528 | asoc->peer.retran_path = transport; | |
3f7a87d2 FF |
529 | if (asoc->peer.last_data_from == peer) |
530 | asoc->peer.last_data_from = transport; | |
531 | ||
7b9438de XL |
532 | if (asoc->strreset_chunk && |
533 | asoc->strreset_chunk->transport == peer) { | |
534 | asoc->strreset_chunk->transport = transport; | |
535 | sctp_transport_reset_reconf_timer(transport); | |
536 | } | |
537 | ||
3f7a87d2 FF |
538 | /* If we remove the transport an INIT was last sent to, set it to |
539 | * NULL. Combined with the update of the retran path above, this | |
540 | * will cause the next INIT to be sent to the next available | |
541 | * transport, maintaining the cycle. | |
542 | */ | |
543 | if (asoc->init_last_sent_to == peer) | |
544 | asoc->init_last_sent_to = NULL; | |
545 | ||
6345b199 WY |
546 | /* If we remove the transport an SHUTDOWN was last sent to, set it |
547 | * to NULL. Combined with the update of the retran path above, this | |
548 | * will cause the next SHUTDOWN to be sent to the next available | |
549 | * transport, maintaining the cycle. | |
550 | */ | |
551 | if (asoc->shutdown_last_sent_to == peer) | |
552 | asoc->shutdown_last_sent_to = NULL; | |
553 | ||
10a43cea WY |
554 | /* If we remove the transport an ASCONF was last sent to, set it to |
555 | * NULL. | |
556 | */ | |
557 | if (asoc->addip_last_asconf && | |
558 | asoc->addip_last_asconf->transport == peer) | |
559 | asoc->addip_last_asconf->transport = NULL; | |
560 | ||
31b02e15 VY |
561 | /* If we have something on the transmitted list, we have to |
562 | * save it off. The best place is the active path. | |
563 | */ | |
564 | if (!list_empty(&peer->transmitted)) { | |
565 | struct sctp_transport *active = asoc->peer.active_path; | |
31b02e15 VY |
566 | |
567 | /* Reset the transport of each chunk on this list */ | |
568 | list_for_each_entry(ch, &peer->transmitted, | |
569 | transmitted_list) { | |
570 | ch->transport = NULL; | |
571 | ch->rtt_in_progress = 0; | |
572 | } | |
573 | ||
574 | list_splice_tail_init(&peer->transmitted, | |
575 | &active->transmitted); | |
576 | ||
577 | /* Start a T3 timer here in case it wasn't running so | |
578 | * that these migrated packets have a chance to get | |
2bccbadf | 579 | * retransmitted. |
31b02e15 VY |
580 | */ |
581 | if (!timer_pending(&active->T3_rtx_timer)) | |
582 | if (!mod_timer(&active->T3_rtx_timer, | |
583 | jiffies + active->rto)) | |
584 | sctp_transport_hold(active); | |
585 | } | |
586 | ||
8376fdc9 XL |
587 | list_for_each_entry(ch, &asoc->outqueue.out_chunk_list, list) |
588 | if (ch->transport == peer) | |
589 | ch->transport = NULL; | |
590 | ||
3f7a87d2 FF |
591 | asoc->peer.transport_count--; |
592 | ||
593 | sctp_transport_free(peer); | |
594 | } | |
595 | ||
1da177e4 LT |
596 | /* Add a transport address to an association. */ |
597 | struct sctp_transport *sctp_assoc_add_peer(struct sctp_association *asoc, | |
598 | const union sctp_addr *addr, | |
dd0fc66f | 599 | const gfp_t gfp, |
3f7a87d2 | 600 | const int peer_state) |
1da177e4 | 601 | { |
89bf3450 | 602 | struct net *net = sock_net(asoc->base.sk); |
1da177e4 LT |
603 | struct sctp_transport *peer; |
604 | struct sctp_sock *sp; | |
605 | unsigned short port; | |
606 | ||
607 | sp = sctp_sk(asoc->base.sk); | |
608 | ||
609 | /* AF_INET and AF_INET6 share common port field. */ | |
4bdf4b5f | 610 | port = ntohs(addr->v4.sin_port); |
1da177e4 | 611 | |
bb33381d DB |
612 | pr_debug("%s: association:%p addr:%pISpc state:%d\n", __func__, |
613 | asoc, &addr->sa, peer_state); | |
3f7a87d2 | 614 | |
1da177e4 LT |
615 | /* Set the port if it has not been set yet. */ |
616 | if (0 == asoc->peer.port) | |
617 | asoc->peer.port = port; | |
618 | ||
619 | /* Check to see if this is a duplicate. */ | |
620 | peer = sctp_assoc_lookup_paddr(asoc, addr); | |
3f7a87d2 | 621 | if (peer) { |
add52379 VY |
622 | /* An UNKNOWN state is only set on transports added by |
623 | * user in sctp_connectx() call. Such transports should be | |
624 | * considered CONFIRMED per RFC 4960, Section 5.4. | |
625 | */ | |
ad8fec17 | 626 | if (peer->state == SCTP_UNKNOWN) { |
add52379 | 627 | peer->state = SCTP_ACTIVE; |
ad8fec17 | 628 | } |
1da177e4 | 629 | return peer; |
3f7a87d2 | 630 | } |
1da177e4 | 631 | |
89bf3450 | 632 | peer = sctp_transport_new(net, addr, gfp); |
1da177e4 LT |
633 | if (!peer) |
634 | return NULL; | |
635 | ||
636 | sctp_transport_set_owner(peer, asoc); | |
637 | ||
52ccb8e9 FF |
638 | /* Initialize the peer's heartbeat interval based on the |
639 | * association configured value. | |
640 | */ | |
641 | peer->hbinterval = asoc->hbinterval; | |
642 | ||
643 | /* Set the path max_retrans. */ | |
644 | peer->pathmaxrxt = asoc->pathmaxrxt; | |
645 | ||
2bccbadf | 646 | /* And the partial failure retrans threshold */ |
5aa93bcf NH |
647 | peer->pf_retrans = asoc->pf_retrans; |
648 | ||
52ccb8e9 FF |
649 | /* Initialize the peer's SACK delay timeout based on the |
650 | * association configured value. | |
651 | */ | |
652 | peer->sackdelay = asoc->sackdelay; | |
d364d927 | 653 | peer->sackfreq = asoc->sackfreq; |
52ccb8e9 FF |
654 | |
655 | /* Enable/disable heartbeat, SACK delay, and path MTU discovery | |
656 | * based on association setting. | |
657 | */ | |
658 | peer->param_flags = asoc->param_flags; | |
659 | ||
8da645e1 VY |
660 | sctp_transport_route(peer, NULL, sp); |
661 | ||
1da177e4 | 662 | /* Initialize the pmtu of the transport. */ |
8da645e1 VY |
663 | if (peer->param_flags & SPP_PMTUD_DISABLE) { |
664 | if (asoc->pathmtu) | |
665 | peer->pathmtu = asoc->pathmtu; | |
666 | else | |
667 | peer->pathmtu = SCTP_DEFAULT_MAXSEGMENT; | |
668 | } | |
1da177e4 LT |
669 | |
670 | /* If this is the first transport addr on this association, | |
671 | * initialize the association PMTU to the peer's PMTU. | |
672 | * If not and the current association PMTU is higher than the new | |
673 | * peer's PMTU, reset the association PMTU to the new peer's PMTU. | |
674 | */ | |
52ccb8e9 FF |
675 | if (asoc->pathmtu) |
676 | asoc->pathmtu = min_t(int, peer->pathmtu, asoc->pathmtu); | |
1da177e4 | 677 | else |
52ccb8e9 | 678 | asoc->pathmtu = peer->pathmtu; |
1da177e4 | 679 | |
bb33381d DB |
680 | pr_debug("%s: association:%p PMTU set to %d\n", __func__, asoc, |
681 | asoc->pathmtu); | |
682 | ||
6d0ccbac | 683 | peer->pmtu_pending = 0; |
1da177e4 | 684 | |
f68b2e05 | 685 | asoc->frag_point = sctp_frag_point(asoc, asoc->pathmtu); |
1da177e4 LT |
686 | |
687 | /* The asoc->peer.port might not be meaningful yet, but | |
688 | * initialize the packet structure anyway. | |
689 | */ | |
690 | sctp_packet_init(&peer->packet, peer, asoc->base.bind_addr.port, | |
691 | asoc->peer.port); | |
692 | ||
693 | /* 7.2.1 Slow-Start | |
694 | * | |
695 | * o The initial cwnd before DATA transmission or after a sufficiently | |
696 | * long idle period MUST be set to | |
697 | * min(4*MTU, max(2*MTU, 4380 bytes)) | |
698 | * | |
699 | * o The initial value of ssthresh MAY be arbitrarily high | |
700 | * (for example, implementations MAY use the size of the | |
701 | * receiver advertised window). | |
702 | */ | |
52ccb8e9 | 703 | peer->cwnd = min(4*asoc->pathmtu, max_t(__u32, 2*asoc->pathmtu, 4380)); |
1da177e4 LT |
704 | |
705 | /* At this point, we may not have the receiver's advertised window, | |
706 | * so initialize ssthresh to the default value and it will be set | |
707 | * later when we process the INIT. | |
708 | */ | |
709 | peer->ssthresh = SCTP_DEFAULT_MAXWINDOW; | |
710 | ||
711 | peer->partial_bytes_acked = 0; | |
712 | peer->flight_size = 0; | |
46d5a808 | 713 | peer->burst_limited = 0; |
1da177e4 | 714 | |
1da177e4 LT |
715 | /* Set the transport's RTO.initial value */ |
716 | peer->rto = asoc->rto_initial; | |
196d6759 | 717 | sctp_max_rto(asoc, peer); |
1da177e4 | 718 | |
3f7a87d2 FF |
719 | /* Set the peer's active state. */ |
720 | peer->state = peer_state; | |
721 | ||
7fda702f XL |
722 | /* Add this peer into the transport hashtable */ |
723 | if (sctp_hash_transport(peer)) { | |
724 | sctp_transport_free(peer); | |
725 | return NULL; | |
726 | } | |
727 | ||
1da177e4 | 728 | /* Attach the remote transport to our asoc. */ |
45122ca2 | 729 | list_add_tail_rcu(&peer->transports, &asoc->peer.transport_addr_list); |
3f7a87d2 | 730 | asoc->peer.transport_count++; |
1da177e4 LT |
731 | |
732 | /* If we do not yet have a primary path, set one. */ | |
733 | if (!asoc->peer.primary_path) { | |
734 | sctp_assoc_set_primary(asoc, peer); | |
735 | asoc->peer.retran_path = peer; | |
736 | } | |
737 | ||
fbdf501c VY |
738 | if (asoc->peer.active_path == asoc->peer.retran_path && |
739 | peer->state != SCTP_UNCONFIRMED) { | |
1da177e4 | 740 | asoc->peer.retran_path = peer; |
3f7a87d2 | 741 | } |
1da177e4 LT |
742 | |
743 | return peer; | |
744 | } | |
745 | ||
746 | /* Delete a transport address from an association. */ | |
747 | void sctp_assoc_del_peer(struct sctp_association *asoc, | |
748 | const union sctp_addr *addr) | |
749 | { | |
750 | struct list_head *pos; | |
751 | struct list_head *temp; | |
1da177e4 LT |
752 | struct sctp_transport *transport; |
753 | ||
754 | list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) { | |
755 | transport = list_entry(pos, struct sctp_transport, transports); | |
756 | if (sctp_cmp_addr_exact(addr, &transport->ipaddr)) { | |
3f7a87d2 FF |
757 | /* Do book keeping for removing the peer and free it. */ |
758 | sctp_assoc_rm_peer(asoc, transport); | |
1da177e4 LT |
759 | break; |
760 | } | |
761 | } | |
1da177e4 LT |
762 | } |
763 | ||
764 | /* Lookup a transport by address. */ | |
765 | struct sctp_transport *sctp_assoc_lookup_paddr( | |
766 | const struct sctp_association *asoc, | |
767 | const union sctp_addr *address) | |
768 | { | |
769 | struct sctp_transport *t; | |
1da177e4 LT |
770 | |
771 | /* Cycle through all transports searching for a peer address. */ | |
772 | ||
9dbc15f0 RD |
773 | list_for_each_entry(t, &asoc->peer.transport_addr_list, |
774 | transports) { | |
1da177e4 LT |
775 | if (sctp_cmp_addr_exact(address, &t->ipaddr)) |
776 | return t; | |
777 | } | |
778 | ||
779 | return NULL; | |
780 | } | |
781 | ||
42e30bf3 VY |
782 | /* Remove all transports except a give one */ |
783 | void sctp_assoc_del_nonprimary_peers(struct sctp_association *asoc, | |
784 | struct sctp_transport *primary) | |
785 | { | |
786 | struct sctp_transport *temp; | |
787 | struct sctp_transport *t; | |
788 | ||
789 | list_for_each_entry_safe(t, temp, &asoc->peer.transport_addr_list, | |
790 | transports) { | |
791 | /* if the current transport is not the primary one, delete it */ | |
792 | if (t != primary) | |
793 | sctp_assoc_rm_peer(asoc, t); | |
794 | } | |
42e30bf3 VY |
795 | } |
796 | ||
1da177e4 LT |
797 | /* Engage in transport control operations. |
798 | * Mark the transport up or down and send a notification to the user. | |
799 | * Select and update the new active and retran paths. | |
800 | */ | |
801 | void sctp_assoc_control_transport(struct sctp_association *asoc, | |
802 | struct sctp_transport *transport, | |
0ceaeebe | 803 | enum sctp_transport_cmd command, |
1da177e4 LT |
804 | sctp_sn_error_t error) |
805 | { | |
1da177e4 | 806 | struct sctp_ulpevent *event; |
0906e20f | 807 | struct sockaddr_storage addr; |
1da177e4 | 808 | int spc_state = 0; |
5aa93bcf | 809 | bool ulp_notify = true; |
1da177e4 LT |
810 | |
811 | /* Record the transition on the transport. */ | |
812 | switch (command) { | |
813 | case SCTP_TRANSPORT_UP: | |
1ae4114d VY |
814 | /* If we are moving from UNCONFIRMED state due |
815 | * to heartbeat success, report the SCTP_ADDR_CONFIRMED | |
816 | * state to the user, otherwise report SCTP_ADDR_AVAILABLE. | |
817 | */ | |
818 | if (SCTP_UNCONFIRMED == transport->state && | |
819 | SCTP_HEARTBEAT_SUCCESS == error) | |
820 | spc_state = SCTP_ADDR_CONFIRMED; | |
821 | else | |
822 | spc_state = SCTP_ADDR_AVAILABLE; | |
5aa93bcf | 823 | /* Don't inform ULP about transition from PF to |
ac4f9599 | 824 | * active state and set cwnd to 1 MTU, see SCTP |
5aa93bcf NH |
825 | * Quick failover draft section 5.1, point 5 |
826 | */ | |
827 | if (transport->state == SCTP_PF) { | |
828 | ulp_notify = false; | |
ac4f9599 | 829 | transport->cwnd = asoc->pathmtu; |
5aa93bcf | 830 | } |
3f7a87d2 | 831 | transport->state = SCTP_ACTIVE; |
1da177e4 LT |
832 | break; |
833 | ||
834 | case SCTP_TRANSPORT_DOWN: | |
40187886 VY |
835 | /* If the transport was never confirmed, do not transition it |
836 | * to inactive state. Also, release the cached route since | |
837 | * there may be a better route next time. | |
cc75689a VY |
838 | */ |
839 | if (transport->state != SCTP_UNCONFIRMED) | |
840 | transport->state = SCTP_INACTIVE; | |
40187886 | 841 | else { |
c86a773c | 842 | sctp_transport_dst_release(transport); |
061079ac | 843 | ulp_notify = false; |
40187886 | 844 | } |
cc75689a | 845 | |
1da177e4 LT |
846 | spc_state = SCTP_ADDR_UNREACHABLE; |
847 | break; | |
848 | ||
5aa93bcf NH |
849 | case SCTP_TRANSPORT_PF: |
850 | transport->state = SCTP_PF; | |
851 | ulp_notify = false; | |
852 | break; | |
853 | ||
1da177e4 LT |
854 | default: |
855 | return; | |
3ff50b79 | 856 | } |
1da177e4 | 857 | |
b82e8f31 DB |
858 | /* Generate and send a SCTP_PEER_ADDR_CHANGE notification |
859 | * to the user. | |
1da177e4 | 860 | */ |
5aa93bcf NH |
861 | if (ulp_notify) { |
862 | memset(&addr, 0, sizeof(struct sockaddr_storage)); | |
863 | memcpy(&addr, &transport->ipaddr, | |
864 | transport->af_specific->sockaddr_len); | |
b82e8f31 | 865 | |
5aa93bcf NH |
866 | event = sctp_ulpevent_make_peer_addr_change(asoc, &addr, |
867 | 0, spc_state, error, GFP_ATOMIC); | |
868 | if (event) | |
869 | sctp_ulpq_tail_event(&asoc->ulpq, event); | |
870 | } | |
1da177e4 LT |
871 | |
872 | /* Select new active and retran paths. */ | |
b82e8f31 | 873 | sctp_select_active_and_retran_path(asoc); |
1da177e4 LT |
874 | } |
875 | ||
876 | /* Hold a reference to an association. */ | |
877 | void sctp_association_hold(struct sctp_association *asoc) | |
878 | { | |
c638457a | 879 | refcount_inc(&asoc->base.refcnt); |
1da177e4 LT |
880 | } |
881 | ||
882 | /* Release a reference to an association and cleanup | |
883 | * if there are no more references. | |
884 | */ | |
885 | void sctp_association_put(struct sctp_association *asoc) | |
886 | { | |
c638457a | 887 | if (refcount_dec_and_test(&asoc->base.refcnt)) |
1da177e4 LT |
888 | sctp_association_destroy(asoc); |
889 | } | |
890 | ||
891 | /* Allocate the next TSN, Transmission Sequence Number, for the given | |
892 | * association. | |
893 | */ | |
894 | __u32 sctp_association_get_next_tsn(struct sctp_association *asoc) | |
895 | { | |
896 | /* From Section 1.6 Serial Number Arithmetic: | |
897 | * Transmission Sequence Numbers wrap around when they reach | |
898 | * 2**32 - 1. That is, the next TSN a DATA chunk MUST use | |
899 | * after transmitting TSN = 2*32 - 1 is TSN = 0. | |
900 | */ | |
901 | __u32 retval = asoc->next_tsn; | |
902 | asoc->next_tsn++; | |
903 | asoc->unack_data++; | |
904 | ||
905 | return retval; | |
906 | } | |
907 | ||
908 | /* Compare two addresses to see if they match. Wildcard addresses | |
909 | * only match themselves. | |
910 | */ | |
911 | int sctp_cmp_addr_exact(const union sctp_addr *ss1, | |
912 | const union sctp_addr *ss2) | |
913 | { | |
914 | struct sctp_af *af; | |
915 | ||
916 | af = sctp_get_af_specific(ss1->sa.sa_family); | |
917 | if (unlikely(!af)) | |
918 | return 0; | |
919 | ||
920 | return af->cmp_addr(ss1, ss2); | |
921 | } | |
922 | ||
923 | /* Return an ecne chunk to get prepended to a packet. | |
924 | * Note: We are sly and return a shared, prealloced chunk. FIXME: | |
925 | * No we don't, but we could/should. | |
926 | */ | |
927 | struct sctp_chunk *sctp_get_ecne_prepend(struct sctp_association *asoc) | |
928 | { | |
8b7318d3 | 929 | if (!asoc->need_ecne) |
930 | return NULL; | |
1da177e4 LT |
931 | |
932 | /* Send ECNE if needed. | |
933 | * Not being able to allocate a chunk here is not deadly. | |
934 | */ | |
8b7318d3 | 935 | return sctp_make_ecne(asoc, asoc->last_ecne_tsn); |
1da177e4 LT |
936 | } |
937 | ||
938 | /* | |
939 | * Find which transport this TSN was sent on. | |
940 | */ | |
941 | struct sctp_transport *sctp_assoc_lookup_tsn(struct sctp_association *asoc, | |
942 | __u32 tsn) | |
943 | { | |
944 | struct sctp_transport *active; | |
945 | struct sctp_transport *match; | |
1da177e4 LT |
946 | struct sctp_transport *transport; |
947 | struct sctp_chunk *chunk; | |
dbc16db1 | 948 | __be32 key = htonl(tsn); |
1da177e4 LT |
949 | |
950 | match = NULL; | |
951 | ||
952 | /* | |
953 | * FIXME: In general, find a more efficient data structure for | |
954 | * searching. | |
955 | */ | |
956 | ||
957 | /* | |
958 | * The general strategy is to search each transport's transmitted | |
959 | * list. Return which transport this TSN lives on. | |
960 | * | |
961 | * Let's be hopeful and check the active_path first. | |
962 | * Another optimization would be to know if there is only one | |
963 | * outbound path and not have to look for the TSN at all. | |
964 | * | |
965 | */ | |
966 | ||
967 | active = asoc->peer.active_path; | |
968 | ||
9dbc15f0 RD |
969 | list_for_each_entry(chunk, &active->transmitted, |
970 | transmitted_list) { | |
1da177e4 LT |
971 | |
972 | if (key == chunk->subh.data_hdr->tsn) { | |
973 | match = active; | |
974 | goto out; | |
975 | } | |
976 | } | |
977 | ||
978 | /* If not found, go search all the other transports. */ | |
9dbc15f0 RD |
979 | list_for_each_entry(transport, &asoc->peer.transport_addr_list, |
980 | transports) { | |
1da177e4 LT |
981 | |
982 | if (transport == active) | |
2317f449 | 983 | continue; |
9dbc15f0 RD |
984 | list_for_each_entry(chunk, &transport->transmitted, |
985 | transmitted_list) { | |
1da177e4 LT |
986 | if (key == chunk->subh.data_hdr->tsn) { |
987 | match = transport; | |
988 | goto out; | |
989 | } | |
990 | } | |
991 | } | |
992 | out: | |
993 | return match; | |
994 | } | |
995 | ||
996 | /* Is this the association we are looking for? */ | |
997 | struct sctp_transport *sctp_assoc_is_match(struct sctp_association *asoc, | |
4110cc25 | 998 | struct net *net, |
1da177e4 LT |
999 | const union sctp_addr *laddr, |
1000 | const union sctp_addr *paddr) | |
1001 | { | |
1002 | struct sctp_transport *transport; | |
1003 | ||
e2fccedb | 1004 | if ((htons(asoc->base.bind_addr.port) == laddr->v4.sin_port) && |
4110cc25 EB |
1005 | (htons(asoc->peer.port) == paddr->v4.sin_port) && |
1006 | net_eq(sock_net(asoc->base.sk), net)) { | |
1da177e4 LT |
1007 | transport = sctp_assoc_lookup_paddr(asoc, paddr); |
1008 | if (!transport) | |
1009 | goto out; | |
1010 | ||
1011 | if (sctp_bind_addr_match(&asoc->base.bind_addr, laddr, | |
1012 | sctp_sk(asoc->base.sk))) | |
1013 | goto out; | |
1014 | } | |
1015 | transport = NULL; | |
1016 | ||
1017 | out: | |
1da177e4 LT |
1018 | return transport; |
1019 | } | |
1020 | ||
1021 | /* Do delayed input processing. This is scheduled by sctp_rcv(). */ | |
c4028958 | 1022 | static void sctp_assoc_bh_rcv(struct work_struct *work) |
1da177e4 | 1023 | { |
c4028958 DH |
1024 | struct sctp_association *asoc = |
1025 | container_of(work, struct sctp_association, | |
1026 | base.inqueue.immediate); | |
55e26eb9 | 1027 | struct net *net = sock_net(asoc->base.sk); |
bfc6f827 | 1028 | union sctp_subtype subtype; |
1da177e4 LT |
1029 | struct sctp_endpoint *ep; |
1030 | struct sctp_chunk *chunk; | |
1da177e4 | 1031 | struct sctp_inq *inqueue; |
3b54f1fd | 1032 | int first_time = 1; /* is this the first time through the loop */ |
1da177e4 | 1033 | int error = 0; |
3b54f1fd | 1034 | int state; |
1da177e4 LT |
1035 | |
1036 | /* The association should be held so we should be safe. */ | |
1037 | ep = asoc->ep; | |
1da177e4 LT |
1038 | |
1039 | inqueue = &asoc->base.inqueue; | |
1040 | sctp_association_hold(asoc); | |
1041 | while (NULL != (chunk = sctp_inq_pop(inqueue))) { | |
1042 | state = asoc->state; | |
1043 | subtype = SCTP_ST_CHUNK(chunk->chunk_hdr->type); | |
1044 | ||
3b54f1fd XL |
1045 | /* If the first chunk in the packet is AUTH, do special |
1046 | * processing specified in Section 6.3 of SCTP-AUTH spec | |
1047 | */ | |
1048 | if (first_time && subtype.chunk == SCTP_CID_AUTH) { | |
1049 | struct sctp_chunkhdr *next_hdr; | |
1050 | ||
1051 | next_hdr = sctp_inq_peek(inqueue); | |
1052 | if (!next_hdr) | |
1053 | goto normal; | |
1054 | ||
1055 | /* If the next chunk is COOKIE-ECHO, skip the AUTH | |
1056 | * chunk while saving a pointer to it so we can do | |
1057 | * Authentication later (during cookie-echo | |
1058 | * processing). | |
1059 | */ | |
1060 | if (next_hdr->type == SCTP_CID_COOKIE_ECHO) { | |
1061 | chunk->auth_chunk = skb_clone(chunk->skb, | |
1062 | GFP_ATOMIC); | |
1063 | chunk->auth = 1; | |
1064 | continue; | |
1065 | } | |
1066 | } | |
1067 | ||
1068 | normal: | |
bbd0d598 VY |
1069 | /* SCTP-AUTH, Section 6.3: |
1070 | * The receiver has a list of chunk types which it expects | |
1071 | * to be received only after an AUTH-chunk. This list has | |
1072 | * been sent to the peer during the association setup. It | |
1073 | * MUST silently discard these chunks if they are not placed | |
1074 | * after an AUTH chunk in the packet. | |
1075 | */ | |
1076 | if (sctp_auth_recv_cid(subtype.chunk, asoc) && !chunk->auth) | |
1077 | continue; | |
1078 | ||
1da177e4 LT |
1079 | /* Remember where the last DATA chunk came from so we |
1080 | * know where to send the SACK. | |
1081 | */ | |
1082 | if (sctp_chunk_is_data(chunk)) | |
1083 | asoc->peer.last_data_from = chunk->transport; | |
196d6759 | 1084 | else { |
55e26eb9 | 1085 | SCTP_INC_STATS(net, SCTP_MIB_INCTRLCHUNKS); |
196d6759 MB |
1086 | asoc->stats.ictrlchunks++; |
1087 | if (chunk->chunk_hdr->type == SCTP_CID_SACK) | |
1088 | asoc->stats.isacks++; | |
1089 | } | |
1da177e4 LT |
1090 | |
1091 | if (chunk->transport) | |
e575235f | 1092 | chunk->transport->last_time_heard = ktime_get(); |
1da177e4 LT |
1093 | |
1094 | /* Run through the state machine. */ | |
55e26eb9 | 1095 | error = sctp_do_sm(net, SCTP_EVENT_T_CHUNK, subtype, |
1da177e4 LT |
1096 | state, ep, asoc, chunk, GFP_ATOMIC); |
1097 | ||
1098 | /* Check to see if the association is freed in response to | |
1099 | * the incoming chunk. If so, get out of the while loop. | |
1100 | */ | |
1101 | if (asoc->base.dead) | |
1102 | break; | |
1103 | ||
1104 | /* If there is an error on chunk, discard this packet. */ | |
1105 | if (error && chunk) | |
1106 | chunk->pdiscard = 1; | |
3b54f1fd XL |
1107 | |
1108 | if (first_time) | |
1109 | first_time = 0; | |
1da177e4 LT |
1110 | } |
1111 | sctp_association_put(asoc); | |
1112 | } | |
1113 | ||
1114 | /* This routine moves an association from its old sk to a new sk. */ | |
1115 | void sctp_assoc_migrate(struct sctp_association *assoc, struct sock *newsk) | |
1116 | { | |
1117 | struct sctp_sock *newsp = sctp_sk(newsk); | |
1118 | struct sock *oldsk = assoc->base.sk; | |
1119 | ||
1120 | /* Delete the association from the old endpoint's list of | |
1121 | * associations. | |
1122 | */ | |
1123 | list_del_init(&assoc->asocs); | |
1124 | ||
1125 | /* Decrement the backlog value for a TCP-style socket. */ | |
1126 | if (sctp_style(oldsk, TCP)) | |
1127 | oldsk->sk_ack_backlog--; | |
1128 | ||
1129 | /* Release references to the old endpoint and the sock. */ | |
1130 | sctp_endpoint_put(assoc->ep); | |
1131 | sock_put(assoc->base.sk); | |
1132 | ||
1133 | /* Get a reference to the new endpoint. */ | |
1134 | assoc->ep = newsp->ep; | |
1135 | sctp_endpoint_hold(assoc->ep); | |
1136 | ||
1137 | /* Get a reference to the new sock. */ | |
1138 | assoc->base.sk = newsk; | |
1139 | sock_hold(assoc->base.sk); | |
1140 | ||
1141 | /* Add the association to the new endpoint's list of associations. */ | |
1142 | sctp_endpoint_add_asoc(newsp->ep, assoc); | |
1143 | } | |
1144 | ||
1145 | /* Update an association (possibly from unexpected COOKIE-ECHO processing). */ | |
5ee8aa68 XL |
1146 | int sctp_assoc_update(struct sctp_association *asoc, |
1147 | struct sctp_association *new) | |
1da177e4 LT |
1148 | { |
1149 | struct sctp_transport *trans; | |
1150 | struct list_head *pos, *temp; | |
1151 | ||
1152 | /* Copy in new parameters of peer. */ | |
1153 | asoc->c = new->c; | |
1154 | asoc->peer.rwnd = new->peer.rwnd; | |
1155 | asoc->peer.sack_needed = new->peer.sack_needed; | |
1be9a950 | 1156 | asoc->peer.auth_capable = new->peer.auth_capable; |
1da177e4 | 1157 | asoc->peer.i = new->peer.i; |
5ee8aa68 XL |
1158 | |
1159 | if (!sctp_tsnmap_init(&asoc->peer.tsn_map, SCTP_TSN_MAP_INITIAL, | |
1160 | asoc->peer.i.initial_tsn, GFP_ATOMIC)) | |
1161 | return -ENOMEM; | |
1da177e4 LT |
1162 | |
1163 | /* Remove any peer addresses not present in the new association. */ | |
1164 | list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) { | |
1165 | trans = list_entry(pos, struct sctp_transport, transports); | |
0c42749c VY |
1166 | if (!sctp_assoc_lookup_paddr(new, &trans->ipaddr)) { |
1167 | sctp_assoc_rm_peer(asoc, trans); | |
1168 | continue; | |
1169 | } | |
749bf921 VY |
1170 | |
1171 | if (asoc->state >= SCTP_STATE_ESTABLISHED) | |
1172 | sctp_transport_reset(trans); | |
1da177e4 LT |
1173 | } |
1174 | ||
1175 | /* If the case is A (association restart), use | |
1176 | * initial_tsn as next_tsn. If the case is B, use | |
1177 | * current next_tsn in case data sent to peer | |
1178 | * has been discarded and needs retransmission. | |
1179 | */ | |
1180 | if (asoc->state >= SCTP_STATE_ESTABLISHED) { | |
1181 | asoc->next_tsn = new->next_tsn; | |
1182 | asoc->ctsn_ack_point = new->ctsn_ack_point; | |
1183 | asoc->adv_peer_ack_point = new->adv_peer_ack_point; | |
1184 | ||
1185 | /* Reinitialize SSN for both local streams | |
1186 | * and peer's streams. | |
1187 | */ | |
cee360ab | 1188 | sctp_stream_clear(&asoc->stream); |
1da177e4 | 1189 | |
0b58a811 VY |
1190 | /* Flush the ULP reassembly and ordered queue. |
1191 | * Any data there will now be stale and will | |
1192 | * cause problems. | |
1193 | */ | |
1194 | sctp_ulpq_flush(&asoc->ulpq); | |
1195 | ||
749bf921 VY |
1196 | /* reset the overall association error count so |
1197 | * that the restarted association doesn't get torn | |
1198 | * down on the next retransmission timer. | |
1199 | */ | |
1200 | asoc->overall_error_count = 0; | |
1201 | ||
1da177e4 LT |
1202 | } else { |
1203 | /* Add any peer addresses from the new association. */ | |
9dbc15f0 | 1204 | list_for_each_entry(trans, &new->peer.transport_addr_list, |
5ee8aa68 XL |
1205 | transports) |
1206 | if (!sctp_assoc_lookup_paddr(asoc, &trans->ipaddr) && | |
1207 | !sctp_assoc_add_peer(asoc, &trans->ipaddr, | |
1208 | GFP_ATOMIC, trans->state)) | |
1209 | return -ENOMEM; | |
1da177e4 LT |
1210 | |
1211 | asoc->ctsn_ack_point = asoc->next_tsn - 1; | |
1212 | asoc->adv_peer_ack_point = asoc->ctsn_ack_point; | |
3ab21379 | 1213 | |
cee360ab XL |
1214 | if (sctp_state(asoc, COOKIE_WAIT)) |
1215 | sctp_stream_update(&asoc->stream, &new->stream); | |
07d93967 | 1216 | |
4abf5a65 | 1217 | /* get a new assoc id if we don't have one yet. */ |
5ee8aa68 XL |
1218 | if (sctp_assoc_set_id(asoc, GFP_ATOMIC)) |
1219 | return -ENOMEM; | |
1da177e4 | 1220 | } |
a29a5bd4 | 1221 | |
9d2c881a | 1222 | /* SCTP-AUTH: Save the peer parameters from the new associations |
730fc3d0 VY |
1223 | * and also move the association shared keys over |
1224 | */ | |
1225 | kfree(asoc->peer.peer_random); | |
1226 | asoc->peer.peer_random = new->peer.peer_random; | |
1227 | new->peer.peer_random = NULL; | |
1228 | ||
1229 | kfree(asoc->peer.peer_chunks); | |
1230 | asoc->peer.peer_chunks = new->peer.peer_chunks; | |
1231 | new->peer.peer_chunks = NULL; | |
1232 | ||
1233 | kfree(asoc->peer.peer_hmacs); | |
1234 | asoc->peer.peer_hmacs = new->peer.peer_hmacs; | |
1235 | new->peer.peer_hmacs = NULL; | |
1236 | ||
5ee8aa68 | 1237 | return sctp_auth_asoc_init_active_key(asoc, GFP_ATOMIC); |
1da177e4 LT |
1238 | } |
1239 | ||
1240 | /* Update the retran path for sending a retransmitted packet. | |
4c47af4d DB |
1241 | * See also RFC4960, 6.4. Multi-Homed SCTP Endpoints: |
1242 | * | |
1243 | * When there is outbound data to send and the primary path | |
1244 | * becomes inactive (e.g., due to failures), or where the | |
1245 | * SCTP user explicitly requests to send data to an | |
1246 | * inactive destination transport address, before reporting | |
1247 | * an error to its ULP, the SCTP endpoint should try to send | |
1248 | * the data to an alternate active destination transport | |
1249 | * address if one exists. | |
1250 | * | |
1251 | * When retransmitting data that timed out, if the endpoint | |
1252 | * is multihomed, it should consider each source-destination | |
1253 | * address pair in its retransmission selection policy. | |
1254 | * When retransmitting timed-out data, the endpoint should | |
1255 | * attempt to pick the most divergent source-destination | |
1256 | * pair from the original source-destination pair to which | |
1257 | * the packet was transmitted. | |
1258 | * | |
1259 | * Note: Rules for picking the most divergent source-destination | |
1260 | * pair are an implementation decision and are not specified | |
1261 | * within this document. | |
1262 | * | |
1263 | * Our basic strategy is to round-robin transports in priorities | |
2103d6b8 | 1264 | * according to sctp_trans_score() e.g., if no such |
4c47af4d DB |
1265 | * transport with state SCTP_ACTIVE exists, round-robin through |
1266 | * SCTP_UNKNOWN, etc. You get the picture. | |
1da177e4 | 1267 | */ |
4c47af4d | 1268 | static u8 sctp_trans_score(const struct sctp_transport *trans) |
1da177e4 | 1269 | { |
2103d6b8 DV |
1270 | switch (trans->state) { |
1271 | case SCTP_ACTIVE: | |
1272 | return 3; /* best case */ | |
1273 | case SCTP_UNKNOWN: | |
1274 | return 2; | |
1275 | case SCTP_PF: | |
1276 | return 1; | |
1277 | default: /* case SCTP_INACTIVE */ | |
1278 | return 0; /* worst case */ | |
1279 | } | |
4c47af4d | 1280 | } |
1da177e4 | 1281 | |
a7288c4d DB |
1282 | static struct sctp_transport *sctp_trans_elect_tie(struct sctp_transport *trans1, |
1283 | struct sctp_transport *trans2) | |
1284 | { | |
1285 | if (trans1->error_count > trans2->error_count) { | |
1286 | return trans2; | |
1287 | } else if (trans1->error_count == trans2->error_count && | |
1288 | ktime_after(trans2->last_time_heard, | |
1289 | trans1->last_time_heard)) { | |
1290 | return trans2; | |
1291 | } else { | |
1292 | return trans1; | |
1293 | } | |
1294 | } | |
1295 | ||
4c47af4d DB |
1296 | static struct sctp_transport *sctp_trans_elect_best(struct sctp_transport *curr, |
1297 | struct sctp_transport *best) | |
1298 | { | |
a7288c4d DB |
1299 | u8 score_curr, score_best; |
1300 | ||
ea4f19c1 | 1301 | if (best == NULL || curr == best) |
4c47af4d | 1302 | return curr; |
4141ddc0 | 1303 | |
a7288c4d DB |
1304 | score_curr = sctp_trans_score(curr); |
1305 | score_best = sctp_trans_score(best); | |
1306 | ||
1307 | /* First, try a score-based selection if both transport states | |
1308 | * differ. If we're in a tie, lets try to make a more clever | |
1309 | * decision here based on error counts and last time heard. | |
1310 | */ | |
1311 | if (score_curr > score_best) | |
1312 | return curr; | |
1313 | else if (score_curr == score_best) | |
39d2adeb | 1314 | return sctp_trans_elect_tie(best, curr); |
a7288c4d DB |
1315 | else |
1316 | return best; | |
4c47af4d | 1317 | } |
1da177e4 | 1318 | |
4c47af4d DB |
1319 | void sctp_assoc_update_retran_path(struct sctp_association *asoc) |
1320 | { | |
1321 | struct sctp_transport *trans = asoc->peer.retran_path; | |
1322 | struct sctp_transport *trans_next = NULL; | |
1da177e4 | 1323 | |
4c47af4d DB |
1324 | /* We're done as we only have the one and only path. */ |
1325 | if (asoc->peer.transport_count == 1) | |
1326 | return; | |
1327 | /* If active_path and retran_path are the same and active, | |
1328 | * then this is the only active path. Use it. | |
1329 | */ | |
1330 | if (asoc->peer.active_path == asoc->peer.retran_path && | |
1331 | asoc->peer.active_path->state == SCTP_ACTIVE) | |
1332 | return; | |
1da177e4 | 1333 | |
4c47af4d DB |
1334 | /* Iterate from retran_path's successor back to retran_path. */ |
1335 | for (trans = list_next_entry(trans, transports); 1; | |
1336 | trans = list_next_entry(trans, transports)) { | |
1337 | /* Manually skip the head element. */ | |
1338 | if (&trans->transports == &asoc->peer.transport_addr_list) | |
1339 | continue; | |
1340 | if (trans->state == SCTP_UNCONFIRMED) | |
1341 | continue; | |
1342 | trans_next = sctp_trans_elect_best(trans, trans_next); | |
1343 | /* Active is good enough for immediate return. */ | |
1344 | if (trans_next->state == SCTP_ACTIVE) | |
4141ddc0 | 1345 | break; |
4c47af4d DB |
1346 | /* We've reached the end, time to update path. */ |
1347 | if (trans == asoc->peer.retran_path) | |
1da177e4 | 1348 | break; |
1da177e4 LT |
1349 | } |
1350 | ||
433131ba | 1351 | asoc->peer.retran_path = trans_next; |
3f7a87d2 | 1352 | |
4c47af4d DB |
1353 | pr_debug("%s: association:%p updated new path to addr:%pISpc\n", |
1354 | __func__, asoc, &asoc->peer.retran_path->ipaddr.sa); | |
3f7a87d2 FF |
1355 | } |
1356 | ||
b82e8f31 DB |
1357 | static void sctp_select_active_and_retran_path(struct sctp_association *asoc) |
1358 | { | |
1359 | struct sctp_transport *trans, *trans_pri = NULL, *trans_sec = NULL; | |
a7288c4d | 1360 | struct sctp_transport *trans_pf = NULL; |
b82e8f31 DB |
1361 | |
1362 | /* Look for the two most recently used active transports. */ | |
1363 | list_for_each_entry(trans, &asoc->peer.transport_addr_list, | |
1364 | transports) { | |
a7288c4d | 1365 | /* Skip uninteresting transports. */ |
b82e8f31 | 1366 | if (trans->state == SCTP_INACTIVE || |
a7288c4d | 1367 | trans->state == SCTP_UNCONFIRMED) |
b82e8f31 | 1368 | continue; |
a7288c4d DB |
1369 | /* Keep track of the best PF transport from our |
1370 | * list in case we don't find an active one. | |
1371 | */ | |
1372 | if (trans->state == SCTP_PF) { | |
1373 | trans_pf = sctp_trans_elect_best(trans, trans_pf); | |
1374 | continue; | |
1375 | } | |
1376 | /* For active transports, pick the most recent ones. */ | |
b82e8f31 | 1377 | if (trans_pri == NULL || |
e575235f DB |
1378 | ktime_after(trans->last_time_heard, |
1379 | trans_pri->last_time_heard)) { | |
b82e8f31 DB |
1380 | trans_sec = trans_pri; |
1381 | trans_pri = trans; | |
1382 | } else if (trans_sec == NULL || | |
e575235f DB |
1383 | ktime_after(trans->last_time_heard, |
1384 | trans_sec->last_time_heard)) { | |
b82e8f31 DB |
1385 | trans_sec = trans; |
1386 | } | |
1387 | } | |
1388 | ||
1389 | /* RFC 2960 6.4 Multi-Homed SCTP Endpoints | |
1390 | * | |
1391 | * By default, an endpoint should always transmit to the primary | |
1392 | * path, unless the SCTP user explicitly specifies the | |
1393 | * destination transport address (and possibly source transport | |
1394 | * address) to use. [If the primary is active but not most recent, | |
1395 | * bump the most recently used transport.] | |
1396 | */ | |
1397 | if ((asoc->peer.primary_path->state == SCTP_ACTIVE || | |
1398 | asoc->peer.primary_path->state == SCTP_UNKNOWN) && | |
1399 | asoc->peer.primary_path != trans_pri) { | |
1400 | trans_sec = trans_pri; | |
1401 | trans_pri = asoc->peer.primary_path; | |
1402 | } | |
1403 | ||
1404 | /* We did not find anything useful for a possible retransmission | |
1405 | * path; either primary path that we found is the the same as | |
1406 | * the current one, or we didn't generally find an active one. | |
1407 | */ | |
1408 | if (trans_sec == NULL) | |
1409 | trans_sec = trans_pri; | |
1410 | ||
1411 | /* If we failed to find a usable transport, just camp on the | |
aa4a83ee | 1412 | * active or pick a PF iff it's the better choice. |
b82e8f31 DB |
1413 | */ |
1414 | if (trans_pri == NULL) { | |
aa4a83ee DB |
1415 | trans_pri = sctp_trans_elect_best(asoc->peer.active_path, trans_pf); |
1416 | trans_sec = trans_pri; | |
b82e8f31 DB |
1417 | } |
1418 | ||
1419 | /* Set the active and retran transports. */ | |
1420 | asoc->peer.active_path = trans_pri; | |
1421 | asoc->peer.retran_path = trans_sec; | |
1422 | } | |
1423 | ||
4c47af4d DB |
1424 | struct sctp_transport * |
1425 | sctp_assoc_choose_alter_transport(struct sctp_association *asoc, | |
1426 | struct sctp_transport *last_sent_to) | |
3f7a87d2 | 1427 | { |
9919b455 WY |
1428 | /* If this is the first time packet is sent, use the active path, |
1429 | * else use the retran path. If the last packet was sent over the | |
3f7a87d2 FF |
1430 | * retran path, update the retran path and use it. |
1431 | */ | |
4c47af4d | 1432 | if (last_sent_to == NULL) { |
1da177e4 | 1433 | return asoc->peer.active_path; |
4c47af4d | 1434 | } else { |
9919b455 | 1435 | if (last_sent_to == asoc->peer.retran_path) |
1da177e4 | 1436 | sctp_assoc_update_retran_path(asoc); |
4c47af4d | 1437 | |
1da177e4 LT |
1438 | return asoc->peer.retran_path; |
1439 | } | |
1da177e4 LT |
1440 | } |
1441 | ||
1442 | /* Update the association's pmtu and frag_point by going through all the | |
1443 | * transports. This routine is called when a transport's PMTU has changed. | |
1444 | */ | |
3ebfdf08 | 1445 | void sctp_assoc_sync_pmtu(struct sctp_association *asoc) |
1da177e4 LT |
1446 | { |
1447 | struct sctp_transport *t; | |
1da177e4 LT |
1448 | __u32 pmtu = 0; |
1449 | ||
1450 | if (!asoc) | |
1451 | return; | |
1452 | ||
1453 | /* Get the lowest pmtu of all the transports. */ | |
9dbc15f0 RD |
1454 | list_for_each_entry(t, &asoc->peer.transport_addr_list, |
1455 | transports) { | |
8a479491 | 1456 | if (t->pmtu_pending && t->dst) { |
3ebfdf08 XL |
1457 | sctp_transport_update_pmtu( |
1458 | t, SCTP_TRUNC4(dst_mtu(t->dst))); | |
8a479491 VY |
1459 | t->pmtu_pending = 0; |
1460 | } | |
52ccb8e9 FF |
1461 | if (!pmtu || (t->pathmtu < pmtu)) |
1462 | pmtu = t->pathmtu; | |
1da177e4 LT |
1463 | } |
1464 | ||
1465 | if (pmtu) { | |
52ccb8e9 | 1466 | asoc->pathmtu = pmtu; |
f68b2e05 | 1467 | asoc->frag_point = sctp_frag_point(asoc, pmtu); |
1da177e4 LT |
1468 | } |
1469 | ||
bb33381d DB |
1470 | pr_debug("%s: asoc:%p, pmtu:%d, frag_point:%d\n", __func__, asoc, |
1471 | asoc->pathmtu, asoc->frag_point); | |
1da177e4 LT |
1472 | } |
1473 | ||
1474 | /* Should we send a SACK to update our peer? */ | |
ce4a03db | 1475 | static inline bool sctp_peer_needs_update(struct sctp_association *asoc) |
1da177e4 | 1476 | { |
e1fc3b14 | 1477 | struct net *net = sock_net(asoc->base.sk); |
1da177e4 LT |
1478 | switch (asoc->state) { |
1479 | case SCTP_STATE_ESTABLISHED: | |
1480 | case SCTP_STATE_SHUTDOWN_PENDING: | |
1481 | case SCTP_STATE_SHUTDOWN_RECEIVED: | |
1482 | case SCTP_STATE_SHUTDOWN_SENT: | |
1483 | if ((asoc->rwnd > asoc->a_rwnd) && | |
90f2f531 | 1484 | ((asoc->rwnd - asoc->a_rwnd) >= max_t(__u32, |
e1fc3b14 | 1485 | (asoc->base.sk->sk_rcvbuf >> net->sctp.rwnd_upd_shift), |
90f2f531 | 1486 | asoc->pathmtu))) |
ce4a03db | 1487 | return true; |
1da177e4 LT |
1488 | break; |
1489 | default: | |
1490 | break; | |
1491 | } | |
ce4a03db | 1492 | return false; |
1da177e4 LT |
1493 | } |
1494 | ||
362d5204 DB |
1495 | /* Increase asoc's rwnd by len and send any window update SACK if needed. */ |
1496 | void sctp_assoc_rwnd_increase(struct sctp_association *asoc, unsigned int len) | |
1da177e4 LT |
1497 | { |
1498 | struct sctp_chunk *sack; | |
1499 | struct timer_list *timer; | |
1500 | ||
362d5204 DB |
1501 | if (asoc->rwnd_over) { |
1502 | if (asoc->rwnd_over >= len) { | |
1503 | asoc->rwnd_over -= len; | |
1504 | } else { | |
1505 | asoc->rwnd += (len - asoc->rwnd_over); | |
1506 | asoc->rwnd_over = 0; | |
1507 | } | |
1508 | } else { | |
1509 | asoc->rwnd += len; | |
1510 | } | |
1da177e4 | 1511 | |
362d5204 DB |
1512 | /* If we had window pressure, start recovering it |
1513 | * once our rwnd had reached the accumulated pressure | |
1514 | * threshold. The idea is to recover slowly, but up | |
1515 | * to the initial advertised window. | |
1516 | */ | |
1636098c | 1517 | if (asoc->rwnd_press) { |
362d5204 DB |
1518 | int change = min(asoc->pathmtu, asoc->rwnd_press); |
1519 | asoc->rwnd += change; | |
1520 | asoc->rwnd_press -= change; | |
1521 | } | |
4d3c46e6 | 1522 | |
362d5204 DB |
1523 | pr_debug("%s: asoc:%p rwnd increased by %d to (%u, %u) - %u\n", |
1524 | __func__, asoc, len, asoc->rwnd, asoc->rwnd_over, | |
1525 | asoc->a_rwnd); | |
1da177e4 LT |
1526 | |
1527 | /* Send a window update SACK if the rwnd has increased by at least the | |
1528 | * minimum of the association's PMTU and half of the receive buffer. | |
1529 | * The algorithm used is similar to the one described in | |
1530 | * Section 4.2.3.3 of RFC 1122. | |
1531 | */ | |
362d5204 | 1532 | if (sctp_peer_needs_update(asoc)) { |
1da177e4 | 1533 | asoc->a_rwnd = asoc->rwnd; |
bb33381d DB |
1534 | |
1535 | pr_debug("%s: sending window update SACK- asoc:%p rwnd:%u " | |
1536 | "a_rwnd:%u\n", __func__, asoc, asoc->rwnd, | |
1537 | asoc->a_rwnd); | |
1538 | ||
1da177e4 LT |
1539 | sack = sctp_make_sack(asoc); |
1540 | if (!sack) | |
1541 | return; | |
1542 | ||
1543 | asoc->peer.sack_needed = 0; | |
1544 | ||
cea8768f | 1545 | sctp_outq_tail(&asoc->outqueue, sack, GFP_ATOMIC); |
1da177e4 LT |
1546 | |
1547 | /* Stop the SACK timer. */ | |
1548 | timer = &asoc->timers[SCTP_EVENT_TIMEOUT_SACK]; | |
25cc4ae9 | 1549 | if (del_timer(timer)) |
1da177e4 LT |
1550 | sctp_association_put(asoc); |
1551 | } | |
1552 | } | |
1553 | ||
362d5204 DB |
1554 | /* Decrease asoc's rwnd by len. */ |
1555 | void sctp_assoc_rwnd_decrease(struct sctp_association *asoc, unsigned int len) | |
1556 | { | |
1557 | int rx_count; | |
1558 | int over = 0; | |
1559 | ||
1560 | if (unlikely(!asoc->rwnd || asoc->rwnd_over)) | |
1561 | pr_debug("%s: association:%p has asoc->rwnd:%u, " | |
1562 | "asoc->rwnd_over:%u!\n", __func__, asoc, | |
1563 | asoc->rwnd, asoc->rwnd_over); | |
1564 | ||
1565 | if (asoc->ep->rcvbuf_policy) | |
1566 | rx_count = atomic_read(&asoc->rmem_alloc); | |
1567 | else | |
1568 | rx_count = atomic_read(&asoc->base.sk->sk_rmem_alloc); | |
1569 | ||
1570 | /* If we've reached or overflowed our receive buffer, announce | |
1571 | * a 0 rwnd if rwnd would still be positive. Store the | |
1572 | * the potential pressure overflow so that the window can be restored | |
1573 | * back to original value. | |
1574 | */ | |
1575 | if (rx_count >= asoc->base.sk->sk_rcvbuf) | |
1576 | over = 1; | |
1577 | ||
1578 | if (asoc->rwnd >= len) { | |
1579 | asoc->rwnd -= len; | |
1580 | if (over) { | |
1581 | asoc->rwnd_press += asoc->rwnd; | |
1582 | asoc->rwnd = 0; | |
1583 | } | |
1584 | } else { | |
58b94d88 | 1585 | asoc->rwnd_over += len - asoc->rwnd; |
362d5204 DB |
1586 | asoc->rwnd = 0; |
1587 | } | |
1588 | ||
1589 | pr_debug("%s: asoc:%p rwnd decreased by %d to (%u, %u, %u)\n", | |
1590 | __func__, asoc, len, asoc->rwnd, asoc->rwnd_over, | |
1591 | asoc->rwnd_press); | |
1592 | } | |
1da177e4 LT |
1593 | |
1594 | /* Build the bind address list for the association based on info from the | |
1595 | * local endpoint and the remote peer. | |
1596 | */ | |
3182cd84 | 1597 | int sctp_assoc_set_bind_addr_from_ep(struct sctp_association *asoc, |
1c662018 | 1598 | enum sctp_scope scope, gfp_t gfp) |
1da177e4 | 1599 | { |
1da177e4 LT |
1600 | int flags; |
1601 | ||
1602 | /* Use scoping rules to determine the subset of addresses from | |
1603 | * the endpoint. | |
1604 | */ | |
1da177e4 LT |
1605 | flags = (PF_INET6 == asoc->base.sk->sk_family) ? SCTP_ADDR6_ALLOWED : 0; |
1606 | if (asoc->peer.ipv4_address) | |
1607 | flags |= SCTP_ADDR4_PEERSUPP; | |
1608 | if (asoc->peer.ipv6_address) | |
1609 | flags |= SCTP_ADDR6_PEERSUPP; | |
1610 | ||
4db67e80 EB |
1611 | return sctp_bind_addr_copy(sock_net(asoc->base.sk), |
1612 | &asoc->base.bind_addr, | |
1da177e4 LT |
1613 | &asoc->ep->base.bind_addr, |
1614 | scope, gfp, flags); | |
1615 | } | |
1616 | ||
1617 | /* Build the association's bind address list from the cookie. */ | |
1618 | int sctp_assoc_set_bind_addr_from_cookie(struct sctp_association *asoc, | |
3182cd84 | 1619 | struct sctp_cookie *cookie, |
dd0fc66f | 1620 | gfp_t gfp) |
1da177e4 LT |
1621 | { |
1622 | int var_size2 = ntohs(cookie->peer_init->chunk_hdr.length); | |
1623 | int var_size3 = cookie->raw_addr_list_len; | |
1624 | __u8 *raw = (__u8 *)cookie->peer_init + var_size2; | |
1625 | ||
1626 | return sctp_raw_to_bind_addrs(&asoc->base.bind_addr, raw, var_size3, | |
1627 | asoc->ep->base.bind_addr.port, gfp); | |
1628 | } | |
1629 | ||
d808ad9a YH |
1630 | /* Lookup laddr in the bind address list of an association. */ |
1631 | int sctp_assoc_lookup_laddr(struct sctp_association *asoc, | |
1da177e4 LT |
1632 | const union sctp_addr *laddr) |
1633 | { | |
559cf710 | 1634 | int found = 0; |
1da177e4 | 1635 | |
1da177e4 LT |
1636 | if ((asoc->base.bind_addr.port == ntohs(laddr->v4.sin_port)) && |
1637 | sctp_bind_addr_match(&asoc->base.bind_addr, laddr, | |
559cf710 | 1638 | sctp_sk(asoc->base.sk))) |
1da177e4 | 1639 | found = 1; |
1da177e4 | 1640 | |
1da177e4 LT |
1641 | return found; |
1642 | } | |
07d93967 VY |
1643 | |
1644 | /* Set an association id for a given association */ | |
1645 | int sctp_assoc_set_id(struct sctp_association *asoc, gfp_t gfp) | |
1646 | { | |
d0164adc | 1647 | bool preload = gfpflags_allow_blocking(gfp); |
94960e8c | 1648 | int ret; |
c6ba68a2 VY |
1649 | |
1650 | /* If the id is already assigned, keep it. */ | |
1651 | if (asoc->assoc_id) | |
94960e8c | 1652 | return 0; |
07d93967 | 1653 | |
94960e8c TH |
1654 | if (preload) |
1655 | idr_preload(gfp); | |
07d93967 | 1656 | spin_lock_bh(&sctp_assocs_id_lock); |
713e00a3 JL |
1657 | /* 0 is not a valid assoc_id, must be >= 1 */ |
1658 | ret = idr_alloc_cyclic(&sctp_assocs_id, asoc, 1, 0, GFP_NOWAIT); | |
07d93967 | 1659 | spin_unlock_bh(&sctp_assocs_id_lock); |
94960e8c TH |
1660 | if (preload) |
1661 | idr_preload_end(); | |
1662 | if (ret < 0) | |
1663 | return ret; | |
07d93967 | 1664 | |
94960e8c TH |
1665 | asoc->assoc_id = (sctp_assoc_t)ret; |
1666 | return 0; | |
07d93967 | 1667 | } |
a08de64d | 1668 | |
8b4472cc WY |
1669 | /* Free the ASCONF queue */ |
1670 | static void sctp_assoc_free_asconf_queue(struct sctp_association *asoc) | |
1671 | { | |
1672 | struct sctp_chunk *asconf; | |
1673 | struct sctp_chunk *tmp; | |
1674 | ||
1675 | list_for_each_entry_safe(asconf, tmp, &asoc->addip_chunk_list, list) { | |
1676 | list_del_init(&asconf->list); | |
1677 | sctp_chunk_free(asconf); | |
1678 | } | |
1679 | } | |
1680 | ||
a08de64d VY |
1681 | /* Free asconf_ack cache */ |
1682 | static void sctp_assoc_free_asconf_acks(struct sctp_association *asoc) | |
1683 | { | |
1684 | struct sctp_chunk *ack; | |
1685 | struct sctp_chunk *tmp; | |
1686 | ||
1687 | list_for_each_entry_safe(ack, tmp, &asoc->asconf_ack_list, | |
1688 | transmitted_list) { | |
1689 | list_del_init(&ack->transmitted_list); | |
1690 | sctp_chunk_free(ack); | |
1691 | } | |
1692 | } | |
1693 | ||
1694 | /* Clean up the ASCONF_ACK queue */ | |
1695 | void sctp_assoc_clean_asconf_ack_cache(const struct sctp_association *asoc) | |
1696 | { | |
1697 | struct sctp_chunk *ack; | |
1698 | struct sctp_chunk *tmp; | |
1699 | ||
25985edc | 1700 | /* We can remove all the entries from the queue up to |
a08de64d VY |
1701 | * the "Peer-Sequence-Number". |
1702 | */ | |
1703 | list_for_each_entry_safe(ack, tmp, &asoc->asconf_ack_list, | |
1704 | transmitted_list) { | |
1705 | if (ack->subh.addip_hdr->serial == | |
1706 | htonl(asoc->peer.addip_serial)) | |
1707 | break; | |
1708 | ||
1709 | list_del_init(&ack->transmitted_list); | |
1710 | sctp_chunk_free(ack); | |
1711 | } | |
1712 | } | |
1713 | ||
1714 | /* Find the ASCONF_ACK whose serial number matches ASCONF */ | |
1715 | struct sctp_chunk *sctp_assoc_lookup_asconf_ack( | |
1716 | const struct sctp_association *asoc, | |
1717 | __be32 serial) | |
1718 | { | |
a8699814 | 1719 | struct sctp_chunk *ack; |
a08de64d VY |
1720 | |
1721 | /* Walk through the list of cached ASCONF-ACKs and find the | |
1722 | * ack chunk whose serial number matches that of the request. | |
1723 | */ | |
1724 | list_for_each_entry(ack, &asoc->asconf_ack_list, transmitted_list) { | |
b69040d8 DB |
1725 | if (sctp_chunk_pending(ack)) |
1726 | continue; | |
a08de64d VY |
1727 | if (ack->subh.addip_hdr->serial == serial) { |
1728 | sctp_chunk_hold(ack); | |
a8699814 | 1729 | return ack; |
a08de64d VY |
1730 | } |
1731 | } | |
1732 | ||
a8699814 | 1733 | return NULL; |
a08de64d | 1734 | } |
a000c01e WY |
1735 | |
1736 | void sctp_asconf_queue_teardown(struct sctp_association *asoc) | |
1737 | { | |
1738 | /* Free any cached ASCONF_ACK chunk. */ | |
1739 | sctp_assoc_free_asconf_acks(asoc); | |
1740 | ||
1741 | /* Free the ASCONF queue. */ | |
1742 | sctp_assoc_free_asconf_queue(asoc); | |
1743 | ||
1744 | /* Free any cached ASCONF chunk. */ | |
1745 | if (asoc->addip_last_asconf) | |
1746 | sctp_chunk_free(asoc->addip_last_asconf); | |
1747 | } |