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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. */ | |
66 | static struct sctp_association *sctp_association_init(struct sctp_association *asoc, | |
67 | const struct sctp_endpoint *ep, | |
68 | const struct sock *sk, | |
69 | sctp_scope_t scope, | |
dd0fc66f | 70 | gfp_t gfp) |
1da177e4 | 71 | { |
e1fc3b14 | 72 | struct net *net = sock_net(sk); |
1da177e4 LT |
73 | struct sctp_sock *sp; |
74 | int i; | |
a29a5bd4 VY |
75 | sctp_paramhdr_t *p; |
76 | int err; | |
1da177e4 LT |
77 | |
78 | /* Retrieve the SCTP per socket area. */ | |
79 | sp = sctp_sk((struct sock *)sk); | |
80 | ||
1da177e4 LT |
81 | /* Discarding const is appropriate here. */ |
82 | asoc->ep = (struct sctp_endpoint *)ep; | |
1da177e4 | 83 | asoc->base.sk = (struct sock *)sk; |
2e0c9e79 DB |
84 | |
85 | sctp_endpoint_hold(asoc->ep); | |
1da177e4 LT |
86 | sock_hold(asoc->base.sk); |
87 | ||
88 | /* Initialize the common base substructure. */ | |
89 | asoc->base.type = SCTP_EP_TYPE_ASSOCIATION; | |
90 | ||
91 | /* Initialize the object handling fields. */ | |
92 | atomic_set(&asoc->base.refcnt, 1); | |
1da177e4 LT |
93 | |
94 | /* Initialize the bind addr area. */ | |
95 | sctp_bind_addr_init(&asoc->base.bind_addr, ep->base.bind_addr.port); | |
1da177e4 LT |
96 | |
97 | asoc->state = SCTP_STATE_CLOSED; | |
52db882f | 98 | asoc->cookie_life = ms_to_ktime(sp->assocparams.sasoc_cookie_life); |
f68b2e05 | 99 | asoc->user_frag = sp->user_frag; |
1da177e4 LT |
100 | |
101 | /* Set the association max_retrans and RTO values from the | |
102 | * socket values. | |
103 | */ | |
104 | asoc->max_retrans = sp->assocparams.sasoc_asocmaxrxt; | |
e1fc3b14 | 105 | asoc->pf_retrans = net->sctp.pf_retrans; |
5aa93bcf | 106 | |
1da177e4 LT |
107 | asoc->rto_initial = msecs_to_jiffies(sp->rtoinfo.srto_initial); |
108 | asoc->rto_max = msecs_to_jiffies(sp->rtoinfo.srto_max); | |
109 | asoc->rto_min = msecs_to_jiffies(sp->rtoinfo.srto_min); | |
110 | ||
52ccb8e9 FF |
111 | /* Initialize the association's heartbeat interval based on the |
112 | * sock configured value. | |
113 | */ | |
114 | asoc->hbinterval = msecs_to_jiffies(sp->hbinterval); | |
115 | ||
116 | /* Initialize path max retrans value. */ | |
117 | asoc->pathmaxrxt = sp->pathmaxrxt; | |
118 | ||
119 | /* Initialize default path MTU. */ | |
120 | asoc->pathmtu = sp->pathmtu; | |
121 | ||
122 | /* Set association default SACK delay */ | |
123 | asoc->sackdelay = msecs_to_jiffies(sp->sackdelay); | |
d364d927 | 124 | asoc->sackfreq = sp->sackfreq; |
52ccb8e9 FF |
125 | |
126 | /* Set the association default flags controlling | |
127 | * Heartbeat, SACK delay, and Path MTU Discovery. | |
128 | */ | |
129 | asoc->param_flags = sp->param_flags; | |
130 | ||
9d2c881a | 131 | /* Initialize the maximum number of new data packets that can be sent |
1da177e4 LT |
132 | * in a burst. |
133 | */ | |
70331571 | 134 | asoc->max_burst = sp->max_burst; |
1da177e4 | 135 | |
1e7d3d90 | 136 | /* initialize association timers */ |
1e7d3d90 VY |
137 | asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_COOKIE] = asoc->rto_initial; |
138 | asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_INIT] = asoc->rto_initial; | |
139 | asoc->timeouts[SCTP_EVENT_TIMEOUT_T2_SHUTDOWN] = asoc->rto_initial; | |
1e7d3d90 VY |
140 | |
141 | /* sctpimpguide Section 2.12.2 | |
142 | * If the 'T5-shutdown-guard' timer is used, it SHOULD be set to the | |
143 | * recommended value of 5 times 'RTO.Max'. | |
144 | */ | |
d808ad9a | 145 | asoc->timeouts[SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD] |
1e7d3d90 VY |
146 | = 5 * asoc->rto_max; |
147 | ||
52ccb8e9 | 148 | asoc->timeouts[SCTP_EVENT_TIMEOUT_SACK] = asoc->sackdelay; |
9f70f46b | 149 | asoc->timeouts[SCTP_EVENT_TIMEOUT_AUTOCLOSE] = sp->autoclose * HZ; |
d808ad9a | 150 | |
421f91d2 | 151 | /* Initializes the timers */ |
b24b8a24 PE |
152 | for (i = SCTP_EVENT_TIMEOUT_NONE; i < SCTP_NUM_TIMEOUT_TYPES; ++i) |
153 | setup_timer(&asoc->timers[i], sctp_timer_events[i], | |
154 | (unsigned long)asoc); | |
1da177e4 LT |
155 | |
156 | /* Pull default initialization values from the sock options. | |
157 | * Note: This assumes that the values have already been | |
158 | * validated in the sock. | |
159 | */ | |
160 | asoc->c.sinit_max_instreams = sp->initmsg.sinit_max_instreams; | |
161 | asoc->c.sinit_num_ostreams = sp->initmsg.sinit_num_ostreams; | |
162 | asoc->max_init_attempts = sp->initmsg.sinit_max_attempts; | |
163 | ||
164 | asoc->max_init_timeo = | |
165 | msecs_to_jiffies(sp->initmsg.sinit_max_init_timeo); | |
166 | ||
1da177e4 LT |
167 | /* Set the local window size for receive. |
168 | * This is also the rcvbuf space per association. | |
169 | * RFC 6 - A SCTP receiver MUST be able to receive a minimum of | |
170 | * 1500 bytes in one SCTP packet. | |
171 | */ | |
049b3ff5 | 172 | if ((sk->sk_rcvbuf/2) < SCTP_DEFAULT_MINWINDOW) |
1da177e4 LT |
173 | asoc->rwnd = SCTP_DEFAULT_MINWINDOW; |
174 | else | |
049b3ff5 | 175 | asoc->rwnd = sk->sk_rcvbuf/2; |
1da177e4 LT |
176 | |
177 | asoc->a_rwnd = asoc->rwnd; | |
178 | ||
1da177e4 LT |
179 | /* Use my own max window until I learn something better. */ |
180 | asoc->peer.rwnd = SCTP_DEFAULT_MAXWINDOW; | |
181 | ||
049b3ff5 NH |
182 | /* Initialize the receive memory counter */ |
183 | atomic_set(&asoc->rmem_alloc, 0); | |
184 | ||
1da177e4 LT |
185 | init_waitqueue_head(&asoc->wait); |
186 | ||
187 | asoc->c.my_vtag = sctp_generate_tag(ep); | |
1da177e4 LT |
188 | asoc->c.my_port = ep->base.bind_addr.port; |
189 | ||
190 | asoc->c.initial_tsn = sctp_generate_tsn(ep); | |
191 | ||
192 | asoc->next_tsn = asoc->c.initial_tsn; | |
193 | ||
194 | asoc->ctsn_ack_point = asoc->next_tsn - 1; | |
195 | asoc->adv_peer_ack_point = asoc->ctsn_ack_point; | |
196 | asoc->highest_sacked = asoc->ctsn_ack_point; | |
197 | asoc->last_cwr_tsn = asoc->ctsn_ack_point; | |
1da177e4 | 198 | |
1da177e4 LT |
199 | /* ADDIP Section 4.1 Asconf Chunk Procedures |
200 | * | |
201 | * When an endpoint has an ASCONF signaled change to be sent to the | |
202 | * remote endpoint it should do the following: | |
203 | * ... | |
204 | * A2) a serial number should be assigned to the chunk. The serial | |
205 | * number SHOULD be a monotonically increasing number. The serial | |
206 | * numbers SHOULD be initialized at the start of the | |
207 | * association to the same value as the initial TSN. | |
208 | */ | |
209 | asoc->addip_serial = asoc->c.initial_tsn; | |
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 | ||
1da177e4 LT |
249 | /* Assume that peer would support both address types unless we are |
250 | * told otherwise. | |
251 | */ | |
252 | asoc->peer.ipv4_address = 1; | |
a2c39584 WY |
253 | if (asoc->base.sk->sk_family == PF_INET6) |
254 | asoc->peer.ipv6_address = 1; | |
1da177e4 LT |
255 | INIT_LIST_HEAD(&asoc->asocs); |
256 | ||
1da177e4 LT |
257 | asoc->default_stream = sp->default_stream; |
258 | asoc->default_ppid = sp->default_ppid; | |
259 | asoc->default_flags = sp->default_flags; | |
260 | asoc->default_context = sp->default_context; | |
261 | asoc->default_timetolive = sp->default_timetolive; | |
6ab792f5 | 262 | asoc->default_rcv_context = sp->default_rcv_context; |
1da177e4 | 263 | |
a29a5bd4 VY |
264 | /* AUTH related initializations */ |
265 | INIT_LIST_HEAD(&asoc->endpoint_shared_keys); | |
266 | err = sctp_auth_asoc_copy_shkeys(ep, asoc, gfp); | |
267 | if (err) | |
268 | goto fail_init; | |
269 | ||
270 | asoc->active_key_id = ep->active_key_id; | |
a29a5bd4 | 271 | |
a29a5bd4 VY |
272 | /* Save the hmacs and chunks list into this association */ |
273 | if (ep->auth_hmacs_list) | |
274 | memcpy(asoc->c.auth_hmacs, ep->auth_hmacs_list, | |
275 | ntohs(ep->auth_hmacs_list->param_hdr.length)); | |
276 | if (ep->auth_chunk_list) | |
277 | memcpy(asoc->c.auth_chunks, ep->auth_chunk_list, | |
278 | ntohs(ep->auth_chunk_list->param_hdr.length)); | |
279 | ||
280 | /* Get the AUTH random number for this association */ | |
281 | p = (sctp_paramhdr_t *)asoc->c.auth_random; | |
282 | p->type = SCTP_PARAM_RANDOM; | |
283 | p->length = htons(sizeof(sctp_paramhdr_t) + SCTP_AUTH_RANDOM_LENGTH); | |
284 | get_random_bytes(p+1, SCTP_AUTH_RANDOM_LENGTH); | |
285 | ||
1da177e4 LT |
286 | return asoc; |
287 | ||
288 | fail_init: | |
1da177e4 | 289 | sock_put(asoc->base.sk); |
2e0c9e79 | 290 | sctp_endpoint_put(asoc->ep); |
1da177e4 LT |
291 | return NULL; |
292 | } | |
293 | ||
294 | /* Allocate and initialize a new association */ | |
295 | struct sctp_association *sctp_association_new(const struct sctp_endpoint *ep, | |
296 | const struct sock *sk, | |
3182cd84 | 297 | sctp_scope_t scope, |
dd0fc66f | 298 | gfp_t gfp) |
1da177e4 LT |
299 | { |
300 | struct sctp_association *asoc; | |
301 | ||
939cfa75 | 302 | asoc = kzalloc(sizeof(*asoc), gfp); |
1da177e4 LT |
303 | if (!asoc) |
304 | goto fail; | |
305 | ||
306 | if (!sctp_association_init(asoc, ep, sk, scope, gfp)) | |
307 | goto fail_init; | |
308 | ||
1da177e4 | 309 | SCTP_DBG_OBJCNT_INC(assoc); |
bb33381d DB |
310 | |
311 | pr_debug("Created asoc %p\n", asoc); | |
1da177e4 LT |
312 | |
313 | return asoc; | |
314 | ||
315 | fail_init: | |
316 | kfree(asoc); | |
317 | fail: | |
318 | return NULL; | |
319 | } | |
320 | ||
321 | /* Free this association if possible. There may still be users, so | |
322 | * the actual deallocation may be delayed. | |
323 | */ | |
324 | void sctp_association_free(struct sctp_association *asoc) | |
325 | { | |
326 | struct sock *sk = asoc->base.sk; | |
327 | struct sctp_transport *transport; | |
328 | struct list_head *pos, *temp; | |
329 | int i; | |
330 | ||
de76e695 VY |
331 | /* Only real associations count against the endpoint, so |
332 | * don't bother for if this is a temporary association. | |
333 | */ | |
d3217b15 | 334 | if (!list_empty(&asoc->asocs)) { |
de76e695 VY |
335 | list_del(&asoc->asocs); |
336 | ||
337 | /* Decrement the backlog value for a TCP-style listening | |
338 | * socket. | |
339 | */ | |
340 | if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING)) | |
341 | sk->sk_ack_backlog--; | |
342 | } | |
1da177e4 LT |
343 | |
344 | /* Mark as dead, so other users can know this structure is | |
345 | * going away. | |
346 | */ | |
0022d2dd | 347 | asoc->base.dead = true; |
1da177e4 LT |
348 | |
349 | /* Dispose of any data lying around in the outqueue. */ | |
350 | sctp_outq_free(&asoc->outqueue); | |
351 | ||
352 | /* Dispose of any pending messages for the upper layer. */ | |
353 | sctp_ulpq_free(&asoc->ulpq); | |
354 | ||
355 | /* Dispose of any pending chunks on the inqueue. */ | |
356 | sctp_inq_free(&asoc->base.inqueue); | |
357 | ||
8e1ee18c VY |
358 | sctp_tsnmap_free(&asoc->peer.tsn_map); |
359 | ||
1da177e4 LT |
360 | /* Free ssnmap storage. */ |
361 | sctp_ssnmap_free(asoc->ssnmap); | |
362 | ||
363 | /* Clean up the bound address list. */ | |
364 | sctp_bind_addr_free(&asoc->base.bind_addr); | |
365 | ||
366 | /* Do we need to go through all of our timers and | |
367 | * delete them? To be safe we will try to delete all, but we | |
368 | * should be able to go through and make a guess based | |
369 | * on our state. | |
370 | */ | |
371 | for (i = SCTP_EVENT_TIMEOUT_NONE; i < SCTP_NUM_TIMEOUT_TYPES; ++i) { | |
25cc4ae9 | 372 | if (del_timer(&asoc->timers[i])) |
1da177e4 LT |
373 | sctp_association_put(asoc); |
374 | } | |
375 | ||
376 | /* Free peer's cached cookie. */ | |
a51482bd | 377 | kfree(asoc->peer.cookie); |
730fc3d0 VY |
378 | kfree(asoc->peer.peer_random); |
379 | kfree(asoc->peer.peer_chunks); | |
380 | kfree(asoc->peer.peer_hmacs); | |
1da177e4 LT |
381 | |
382 | /* Release the transport structures. */ | |
383 | list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) { | |
384 | transport = list_entry(pos, struct sctp_transport, transports); | |
45122ca2 | 385 | list_del_rcu(pos); |
1da177e4 LT |
386 | sctp_transport_free(transport); |
387 | } | |
388 | ||
3f7a87d2 FF |
389 | asoc->peer.transport_count = 0; |
390 | ||
a000c01e | 391 | sctp_asconf_queue_teardown(asoc); |
1da177e4 | 392 | |
8a07eb0a MH |
393 | /* Free pending address space being deleted */ |
394 | if (asoc->asconf_addr_del_pending != NULL) | |
395 | kfree(asoc->asconf_addr_del_pending); | |
396 | ||
a29a5bd4 VY |
397 | /* AUTH - Free the endpoint shared keys */ |
398 | sctp_auth_destroy_keys(&asoc->endpoint_shared_keys); | |
399 | ||
400 | /* AUTH - Free the association shared key */ | |
401 | sctp_auth_key_put(asoc->asoc_shared_key); | |
402 | ||
1da177e4 LT |
403 | sctp_association_put(asoc); |
404 | } | |
405 | ||
406 | /* Cleanup and free up an association. */ | |
407 | static void sctp_association_destroy(struct sctp_association *asoc) | |
408 | { | |
bb33381d DB |
409 | if (unlikely(!asoc->base.dead)) { |
410 | WARN(1, "Attempt to destroy undead association %p!\n", asoc); | |
411 | return; | |
412 | } | |
1da177e4 LT |
413 | |
414 | sctp_endpoint_put(asoc->ep); | |
415 | sock_put(asoc->base.sk); | |
416 | ||
417 | if (asoc->assoc_id != 0) { | |
418 | spin_lock_bh(&sctp_assocs_id_lock); | |
419 | idr_remove(&sctp_assocs_id, asoc->assoc_id); | |
420 | spin_unlock_bh(&sctp_assocs_id_lock); | |
421 | } | |
422 | ||
547b792c | 423 | WARN_ON(atomic_read(&asoc->rmem_alloc)); |
049b3ff5 | 424 | |
ff2266cd DB |
425 | kfree(asoc); |
426 | SCTP_DBG_OBJCNT_DEC(assoc); | |
1da177e4 LT |
427 | } |
428 | ||
429 | /* Change the primary destination address for the peer. */ | |
430 | void sctp_assoc_set_primary(struct sctp_association *asoc, | |
431 | struct sctp_transport *transport) | |
432 | { | |
319fa2a2 VY |
433 | int changeover = 0; |
434 | ||
435 | /* it's a changeover only if we already have a primary path | |
436 | * that we are changing | |
437 | */ | |
438 | if (asoc->peer.primary_path != NULL && | |
439 | asoc->peer.primary_path != transport) | |
440 | changeover = 1 ; | |
441 | ||
1da177e4 LT |
442 | asoc->peer.primary_path = transport; |
443 | ||
444 | /* Set a default msg_name for events. */ | |
445 | memcpy(&asoc->peer.primary_addr, &transport->ipaddr, | |
446 | sizeof(union sctp_addr)); | |
447 | ||
448 | /* If the primary path is changing, assume that the | |
449 | * user wants to use this new path. | |
450 | */ | |
ad8fec17 SS |
451 | if ((transport->state == SCTP_ACTIVE) || |
452 | (transport->state == SCTP_UNKNOWN)) | |
1da177e4 LT |
453 | asoc->peer.active_path = transport; |
454 | ||
455 | /* | |
456 | * SFR-CACC algorithm: | |
457 | * Upon the receipt of a request to change the primary | |
458 | * destination address, on the data structure for the new | |
459 | * primary destination, the sender MUST do the following: | |
460 | * | |
461 | * 1) If CHANGEOVER_ACTIVE is set, then there was a switch | |
462 | * to this destination address earlier. The sender MUST set | |
463 | * CYCLING_CHANGEOVER to indicate that this switch is a | |
464 | * double switch to the same destination address. | |
e0e9db17 VY |
465 | * |
466 | * Really, only bother is we have data queued or outstanding on | |
467 | * the association. | |
1da177e4 | 468 | */ |
e0e9db17 VY |
469 | if (!asoc->outqueue.outstanding_bytes && !asoc->outqueue.out_qlen) |
470 | return; | |
471 | ||
1da177e4 | 472 | if (transport->cacc.changeover_active) |
319fa2a2 | 473 | transport->cacc.cycling_changeover = changeover; |
1da177e4 LT |
474 | |
475 | /* 2) The sender MUST set CHANGEOVER_ACTIVE to indicate that | |
476 | * a changeover has occurred. | |
477 | */ | |
319fa2a2 | 478 | transport->cacc.changeover_active = changeover; |
1da177e4 LT |
479 | |
480 | /* 3) The sender MUST store the next TSN to be sent in | |
481 | * next_tsn_at_change. | |
482 | */ | |
483 | transport->cacc.next_tsn_at_change = asoc->next_tsn; | |
484 | } | |
485 | ||
3f7a87d2 FF |
486 | /* Remove a transport from an association. */ |
487 | void sctp_assoc_rm_peer(struct sctp_association *asoc, | |
488 | struct sctp_transport *peer) | |
489 | { | |
490 | struct list_head *pos; | |
491 | struct sctp_transport *transport; | |
492 | ||
bb33381d DB |
493 | pr_debug("%s: association:%p addr:%pISpc\n", |
494 | __func__, asoc, &peer->ipaddr.sa); | |
3f7a87d2 FF |
495 | |
496 | /* If we are to remove the current retran_path, update it | |
497 | * to the next peer before removing this peer from the list. | |
498 | */ | |
499 | if (asoc->peer.retran_path == peer) | |
500 | sctp_assoc_update_retran_path(asoc); | |
501 | ||
502 | /* Remove this peer from the list. */ | |
45122ca2 | 503 | list_del_rcu(&peer->transports); |
3f7a87d2 FF |
504 | |
505 | /* Get the first transport of asoc. */ | |
506 | pos = asoc->peer.transport_addr_list.next; | |
507 | transport = list_entry(pos, struct sctp_transport, transports); | |
508 | ||
509 | /* Update any entries that match the peer to be deleted. */ | |
510 | if (asoc->peer.primary_path == peer) | |
511 | sctp_assoc_set_primary(asoc, transport); | |
512 | if (asoc->peer.active_path == peer) | |
513 | asoc->peer.active_path = transport; | |
9494c7c5 WY |
514 | if (asoc->peer.retran_path == peer) |
515 | asoc->peer.retran_path = transport; | |
3f7a87d2 FF |
516 | if (asoc->peer.last_data_from == peer) |
517 | asoc->peer.last_data_from = transport; | |
518 | ||
519 | /* If we remove the transport an INIT was last sent to, set it to | |
520 | * NULL. Combined with the update of the retran path above, this | |
521 | * will cause the next INIT to be sent to the next available | |
522 | * transport, maintaining the cycle. | |
523 | */ | |
524 | if (asoc->init_last_sent_to == peer) | |
525 | asoc->init_last_sent_to = NULL; | |
526 | ||
6345b199 WY |
527 | /* If we remove the transport an SHUTDOWN was last sent to, set it |
528 | * to NULL. Combined with the update of the retran path above, this | |
529 | * will cause the next SHUTDOWN to be sent to the next available | |
530 | * transport, maintaining the cycle. | |
531 | */ | |
532 | if (asoc->shutdown_last_sent_to == peer) | |
533 | asoc->shutdown_last_sent_to = NULL; | |
534 | ||
10a43cea WY |
535 | /* If we remove the transport an ASCONF was last sent to, set it to |
536 | * NULL. | |
537 | */ | |
538 | if (asoc->addip_last_asconf && | |
539 | asoc->addip_last_asconf->transport == peer) | |
540 | asoc->addip_last_asconf->transport = NULL; | |
541 | ||
31b02e15 VY |
542 | /* If we have something on the transmitted list, we have to |
543 | * save it off. The best place is the active path. | |
544 | */ | |
545 | if (!list_empty(&peer->transmitted)) { | |
546 | struct sctp_transport *active = asoc->peer.active_path; | |
547 | struct sctp_chunk *ch; | |
548 | ||
549 | /* Reset the transport of each chunk on this list */ | |
550 | list_for_each_entry(ch, &peer->transmitted, | |
551 | transmitted_list) { | |
552 | ch->transport = NULL; | |
553 | ch->rtt_in_progress = 0; | |
554 | } | |
555 | ||
556 | list_splice_tail_init(&peer->transmitted, | |
557 | &active->transmitted); | |
558 | ||
559 | /* Start a T3 timer here in case it wasn't running so | |
560 | * that these migrated packets have a chance to get | |
2bccbadf | 561 | * retransmitted. |
31b02e15 VY |
562 | */ |
563 | if (!timer_pending(&active->T3_rtx_timer)) | |
564 | if (!mod_timer(&active->T3_rtx_timer, | |
565 | jiffies + active->rto)) | |
566 | sctp_transport_hold(active); | |
567 | } | |
568 | ||
3f7a87d2 FF |
569 | asoc->peer.transport_count--; |
570 | ||
571 | sctp_transport_free(peer); | |
572 | } | |
573 | ||
1da177e4 LT |
574 | /* Add a transport address to an association. */ |
575 | struct sctp_transport *sctp_assoc_add_peer(struct sctp_association *asoc, | |
576 | const union sctp_addr *addr, | |
dd0fc66f | 577 | const gfp_t gfp, |
3f7a87d2 | 578 | const int peer_state) |
1da177e4 | 579 | { |
89bf3450 | 580 | struct net *net = sock_net(asoc->base.sk); |
1da177e4 LT |
581 | struct sctp_transport *peer; |
582 | struct sctp_sock *sp; | |
583 | unsigned short port; | |
584 | ||
585 | sp = sctp_sk(asoc->base.sk); | |
586 | ||
587 | /* AF_INET and AF_INET6 share common port field. */ | |
4bdf4b5f | 588 | port = ntohs(addr->v4.sin_port); |
1da177e4 | 589 | |
bb33381d DB |
590 | pr_debug("%s: association:%p addr:%pISpc state:%d\n", __func__, |
591 | asoc, &addr->sa, peer_state); | |
3f7a87d2 | 592 | |
1da177e4 LT |
593 | /* Set the port if it has not been set yet. */ |
594 | if (0 == asoc->peer.port) | |
595 | asoc->peer.port = port; | |
596 | ||
597 | /* Check to see if this is a duplicate. */ | |
598 | peer = sctp_assoc_lookup_paddr(asoc, addr); | |
3f7a87d2 | 599 | if (peer) { |
add52379 VY |
600 | /* An UNKNOWN state is only set on transports added by |
601 | * user in sctp_connectx() call. Such transports should be | |
602 | * considered CONFIRMED per RFC 4960, Section 5.4. | |
603 | */ | |
ad8fec17 | 604 | if (peer->state == SCTP_UNKNOWN) { |
add52379 | 605 | peer->state = SCTP_ACTIVE; |
ad8fec17 | 606 | } |
1da177e4 | 607 | return peer; |
3f7a87d2 | 608 | } |
1da177e4 | 609 | |
89bf3450 | 610 | peer = sctp_transport_new(net, addr, gfp); |
1da177e4 LT |
611 | if (!peer) |
612 | return NULL; | |
613 | ||
614 | sctp_transport_set_owner(peer, asoc); | |
615 | ||
52ccb8e9 FF |
616 | /* Initialize the peer's heartbeat interval based on the |
617 | * association configured value. | |
618 | */ | |
619 | peer->hbinterval = asoc->hbinterval; | |
620 | ||
621 | /* Set the path max_retrans. */ | |
622 | peer->pathmaxrxt = asoc->pathmaxrxt; | |
623 | ||
2bccbadf | 624 | /* And the partial failure retrans threshold */ |
5aa93bcf NH |
625 | peer->pf_retrans = asoc->pf_retrans; |
626 | ||
52ccb8e9 FF |
627 | /* Initialize the peer's SACK delay timeout based on the |
628 | * association configured value. | |
629 | */ | |
630 | peer->sackdelay = asoc->sackdelay; | |
d364d927 | 631 | peer->sackfreq = asoc->sackfreq; |
52ccb8e9 FF |
632 | |
633 | /* Enable/disable heartbeat, SACK delay, and path MTU discovery | |
634 | * based on association setting. | |
635 | */ | |
636 | peer->param_flags = asoc->param_flags; | |
637 | ||
8da645e1 VY |
638 | sctp_transport_route(peer, NULL, sp); |
639 | ||
1da177e4 | 640 | /* Initialize the pmtu of the transport. */ |
8da645e1 VY |
641 | if (peer->param_flags & SPP_PMTUD_DISABLE) { |
642 | if (asoc->pathmtu) | |
643 | peer->pathmtu = asoc->pathmtu; | |
644 | else | |
645 | peer->pathmtu = SCTP_DEFAULT_MAXSEGMENT; | |
646 | } | |
1da177e4 LT |
647 | |
648 | /* If this is the first transport addr on this association, | |
649 | * initialize the association PMTU to the peer's PMTU. | |
650 | * If not and the current association PMTU is higher than the new | |
651 | * peer's PMTU, reset the association PMTU to the new peer's PMTU. | |
652 | */ | |
52ccb8e9 FF |
653 | if (asoc->pathmtu) |
654 | asoc->pathmtu = min_t(int, peer->pathmtu, asoc->pathmtu); | |
1da177e4 | 655 | else |
52ccb8e9 | 656 | asoc->pathmtu = peer->pathmtu; |
1da177e4 | 657 | |
bb33381d DB |
658 | pr_debug("%s: association:%p PMTU set to %d\n", __func__, asoc, |
659 | asoc->pathmtu); | |
660 | ||
6d0ccbac | 661 | peer->pmtu_pending = 0; |
1da177e4 | 662 | |
f68b2e05 | 663 | asoc->frag_point = sctp_frag_point(asoc, asoc->pathmtu); |
1da177e4 LT |
664 | |
665 | /* The asoc->peer.port might not be meaningful yet, but | |
666 | * initialize the packet structure anyway. | |
667 | */ | |
668 | sctp_packet_init(&peer->packet, peer, asoc->base.bind_addr.port, | |
669 | asoc->peer.port); | |
670 | ||
671 | /* 7.2.1 Slow-Start | |
672 | * | |
673 | * o The initial cwnd before DATA transmission or after a sufficiently | |
674 | * long idle period MUST be set to | |
675 | * min(4*MTU, max(2*MTU, 4380 bytes)) | |
676 | * | |
677 | * o The initial value of ssthresh MAY be arbitrarily high | |
678 | * (for example, implementations MAY use the size of the | |
679 | * receiver advertised window). | |
680 | */ | |
52ccb8e9 | 681 | peer->cwnd = min(4*asoc->pathmtu, max_t(__u32, 2*asoc->pathmtu, 4380)); |
1da177e4 LT |
682 | |
683 | /* At this point, we may not have the receiver's advertised window, | |
684 | * so initialize ssthresh to the default value and it will be set | |
685 | * later when we process the INIT. | |
686 | */ | |
687 | peer->ssthresh = SCTP_DEFAULT_MAXWINDOW; | |
688 | ||
689 | peer->partial_bytes_acked = 0; | |
690 | peer->flight_size = 0; | |
46d5a808 | 691 | peer->burst_limited = 0; |
1da177e4 | 692 | |
1da177e4 LT |
693 | /* Set the transport's RTO.initial value */ |
694 | peer->rto = asoc->rto_initial; | |
196d6759 | 695 | sctp_max_rto(asoc, peer); |
1da177e4 | 696 | |
3f7a87d2 FF |
697 | /* Set the peer's active state. */ |
698 | peer->state = peer_state; | |
699 | ||
1da177e4 | 700 | /* Attach the remote transport to our asoc. */ |
45122ca2 | 701 | list_add_tail_rcu(&peer->transports, &asoc->peer.transport_addr_list); |
3f7a87d2 | 702 | asoc->peer.transport_count++; |
1da177e4 LT |
703 | |
704 | /* If we do not yet have a primary path, set one. */ | |
705 | if (!asoc->peer.primary_path) { | |
706 | sctp_assoc_set_primary(asoc, peer); | |
707 | asoc->peer.retran_path = peer; | |
708 | } | |
709 | ||
fbdf501c VY |
710 | if (asoc->peer.active_path == asoc->peer.retran_path && |
711 | peer->state != SCTP_UNCONFIRMED) { | |
1da177e4 | 712 | asoc->peer.retran_path = peer; |
3f7a87d2 | 713 | } |
1da177e4 LT |
714 | |
715 | return peer; | |
716 | } | |
717 | ||
718 | /* Delete a transport address from an association. */ | |
719 | void sctp_assoc_del_peer(struct sctp_association *asoc, | |
720 | const union sctp_addr *addr) | |
721 | { | |
722 | struct list_head *pos; | |
723 | struct list_head *temp; | |
1da177e4 LT |
724 | struct sctp_transport *transport; |
725 | ||
726 | list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) { | |
727 | transport = list_entry(pos, struct sctp_transport, transports); | |
728 | if (sctp_cmp_addr_exact(addr, &transport->ipaddr)) { | |
3f7a87d2 FF |
729 | /* Do book keeping for removing the peer and free it. */ |
730 | sctp_assoc_rm_peer(asoc, transport); | |
1da177e4 LT |
731 | break; |
732 | } | |
733 | } | |
1da177e4 LT |
734 | } |
735 | ||
736 | /* Lookup a transport by address. */ | |
737 | struct sctp_transport *sctp_assoc_lookup_paddr( | |
738 | const struct sctp_association *asoc, | |
739 | const union sctp_addr *address) | |
740 | { | |
741 | struct sctp_transport *t; | |
1da177e4 LT |
742 | |
743 | /* Cycle through all transports searching for a peer address. */ | |
744 | ||
9dbc15f0 RD |
745 | list_for_each_entry(t, &asoc->peer.transport_addr_list, |
746 | transports) { | |
1da177e4 LT |
747 | if (sctp_cmp_addr_exact(address, &t->ipaddr)) |
748 | return t; | |
749 | } | |
750 | ||
751 | return NULL; | |
752 | } | |
753 | ||
42e30bf3 VY |
754 | /* Remove all transports except a give one */ |
755 | void sctp_assoc_del_nonprimary_peers(struct sctp_association *asoc, | |
756 | struct sctp_transport *primary) | |
757 | { | |
758 | struct sctp_transport *temp; | |
759 | struct sctp_transport *t; | |
760 | ||
761 | list_for_each_entry_safe(t, temp, &asoc->peer.transport_addr_list, | |
762 | transports) { | |
763 | /* if the current transport is not the primary one, delete it */ | |
764 | if (t != primary) | |
765 | sctp_assoc_rm_peer(asoc, t); | |
766 | } | |
42e30bf3 VY |
767 | } |
768 | ||
1da177e4 LT |
769 | /* Engage in transport control operations. |
770 | * Mark the transport up or down and send a notification to the user. | |
771 | * Select and update the new active and retran paths. | |
772 | */ | |
773 | void sctp_assoc_control_transport(struct sctp_association *asoc, | |
774 | struct sctp_transport *transport, | |
775 | sctp_transport_cmd_t command, | |
776 | sctp_sn_error_t error) | |
777 | { | |
1da177e4 | 778 | struct sctp_ulpevent *event; |
0906e20f | 779 | struct sockaddr_storage addr; |
1da177e4 | 780 | int spc_state = 0; |
5aa93bcf | 781 | bool ulp_notify = true; |
1da177e4 LT |
782 | |
783 | /* Record the transition on the transport. */ | |
784 | switch (command) { | |
785 | case SCTP_TRANSPORT_UP: | |
1ae4114d VY |
786 | /* If we are moving from UNCONFIRMED state due |
787 | * to heartbeat success, report the SCTP_ADDR_CONFIRMED | |
788 | * state to the user, otherwise report SCTP_ADDR_AVAILABLE. | |
789 | */ | |
790 | if (SCTP_UNCONFIRMED == transport->state && | |
791 | SCTP_HEARTBEAT_SUCCESS == error) | |
792 | spc_state = SCTP_ADDR_CONFIRMED; | |
793 | else | |
794 | spc_state = SCTP_ADDR_AVAILABLE; | |
5aa93bcf | 795 | /* Don't inform ULP about transition from PF to |
ac4f9599 | 796 | * active state and set cwnd to 1 MTU, see SCTP |
5aa93bcf NH |
797 | * Quick failover draft section 5.1, point 5 |
798 | */ | |
799 | if (transport->state == SCTP_PF) { | |
800 | ulp_notify = false; | |
ac4f9599 | 801 | transport->cwnd = asoc->pathmtu; |
5aa93bcf | 802 | } |
3f7a87d2 | 803 | transport->state = SCTP_ACTIVE; |
1da177e4 LT |
804 | break; |
805 | ||
806 | case SCTP_TRANSPORT_DOWN: | |
40187886 VY |
807 | /* If the transport was never confirmed, do not transition it |
808 | * to inactive state. Also, release the cached route since | |
809 | * there may be a better route next time. | |
cc75689a VY |
810 | */ |
811 | if (transport->state != SCTP_UNCONFIRMED) | |
812 | transport->state = SCTP_INACTIVE; | |
40187886 VY |
813 | else { |
814 | dst_release(transport->dst); | |
815 | transport->dst = NULL; | |
061079ac | 816 | ulp_notify = false; |
40187886 | 817 | } |
cc75689a | 818 | |
1da177e4 LT |
819 | spc_state = SCTP_ADDR_UNREACHABLE; |
820 | break; | |
821 | ||
5aa93bcf NH |
822 | case SCTP_TRANSPORT_PF: |
823 | transport->state = SCTP_PF; | |
824 | ulp_notify = false; | |
825 | break; | |
826 | ||
1da177e4 LT |
827 | default: |
828 | return; | |
3ff50b79 | 829 | } |
1da177e4 | 830 | |
b82e8f31 DB |
831 | /* Generate and send a SCTP_PEER_ADDR_CHANGE notification |
832 | * to the user. | |
1da177e4 | 833 | */ |
5aa93bcf NH |
834 | if (ulp_notify) { |
835 | memset(&addr, 0, sizeof(struct sockaddr_storage)); | |
836 | memcpy(&addr, &transport->ipaddr, | |
837 | transport->af_specific->sockaddr_len); | |
b82e8f31 | 838 | |
5aa93bcf NH |
839 | event = sctp_ulpevent_make_peer_addr_change(asoc, &addr, |
840 | 0, spc_state, error, GFP_ATOMIC); | |
841 | if (event) | |
842 | sctp_ulpq_tail_event(&asoc->ulpq, event); | |
843 | } | |
1da177e4 LT |
844 | |
845 | /* Select new active and retran paths. */ | |
b82e8f31 | 846 | sctp_select_active_and_retran_path(asoc); |
1da177e4 LT |
847 | } |
848 | ||
849 | /* Hold a reference to an association. */ | |
850 | void sctp_association_hold(struct sctp_association *asoc) | |
851 | { | |
852 | atomic_inc(&asoc->base.refcnt); | |
853 | } | |
854 | ||
855 | /* Release a reference to an association and cleanup | |
856 | * if there are no more references. | |
857 | */ | |
858 | void sctp_association_put(struct sctp_association *asoc) | |
859 | { | |
860 | if (atomic_dec_and_test(&asoc->base.refcnt)) | |
861 | sctp_association_destroy(asoc); | |
862 | } | |
863 | ||
864 | /* Allocate the next TSN, Transmission Sequence Number, for the given | |
865 | * association. | |
866 | */ | |
867 | __u32 sctp_association_get_next_tsn(struct sctp_association *asoc) | |
868 | { | |
869 | /* From Section 1.6 Serial Number Arithmetic: | |
870 | * Transmission Sequence Numbers wrap around when they reach | |
871 | * 2**32 - 1. That is, the next TSN a DATA chunk MUST use | |
872 | * after transmitting TSN = 2*32 - 1 is TSN = 0. | |
873 | */ | |
874 | __u32 retval = asoc->next_tsn; | |
875 | asoc->next_tsn++; | |
876 | asoc->unack_data++; | |
877 | ||
878 | return retval; | |
879 | } | |
880 | ||
881 | /* Compare two addresses to see if they match. Wildcard addresses | |
882 | * only match themselves. | |
883 | */ | |
884 | int sctp_cmp_addr_exact(const union sctp_addr *ss1, | |
885 | const union sctp_addr *ss2) | |
886 | { | |
887 | struct sctp_af *af; | |
888 | ||
889 | af = sctp_get_af_specific(ss1->sa.sa_family); | |
890 | if (unlikely(!af)) | |
891 | return 0; | |
892 | ||
893 | return af->cmp_addr(ss1, ss2); | |
894 | } | |
895 | ||
896 | /* Return an ecne chunk to get prepended to a packet. | |
897 | * Note: We are sly and return a shared, prealloced chunk. FIXME: | |
898 | * No we don't, but we could/should. | |
899 | */ | |
900 | struct sctp_chunk *sctp_get_ecne_prepend(struct sctp_association *asoc) | |
901 | { | |
8b7318d3 | 902 | if (!asoc->need_ecne) |
903 | return NULL; | |
1da177e4 LT |
904 | |
905 | /* Send ECNE if needed. | |
906 | * Not being able to allocate a chunk here is not deadly. | |
907 | */ | |
8b7318d3 | 908 | return sctp_make_ecne(asoc, asoc->last_ecne_tsn); |
1da177e4 LT |
909 | } |
910 | ||
911 | /* | |
912 | * Find which transport this TSN was sent on. | |
913 | */ | |
914 | struct sctp_transport *sctp_assoc_lookup_tsn(struct sctp_association *asoc, | |
915 | __u32 tsn) | |
916 | { | |
917 | struct sctp_transport *active; | |
918 | struct sctp_transport *match; | |
1da177e4 LT |
919 | struct sctp_transport *transport; |
920 | struct sctp_chunk *chunk; | |
dbc16db1 | 921 | __be32 key = htonl(tsn); |
1da177e4 LT |
922 | |
923 | match = NULL; | |
924 | ||
925 | /* | |
926 | * FIXME: In general, find a more efficient data structure for | |
927 | * searching. | |
928 | */ | |
929 | ||
930 | /* | |
931 | * The general strategy is to search each transport's transmitted | |
932 | * list. Return which transport this TSN lives on. | |
933 | * | |
934 | * Let's be hopeful and check the active_path first. | |
935 | * Another optimization would be to know if there is only one | |
936 | * outbound path and not have to look for the TSN at all. | |
937 | * | |
938 | */ | |
939 | ||
940 | active = asoc->peer.active_path; | |
941 | ||
9dbc15f0 RD |
942 | list_for_each_entry(chunk, &active->transmitted, |
943 | transmitted_list) { | |
1da177e4 LT |
944 | |
945 | if (key == chunk->subh.data_hdr->tsn) { | |
946 | match = active; | |
947 | goto out; | |
948 | } | |
949 | } | |
950 | ||
951 | /* If not found, go search all the other transports. */ | |
9dbc15f0 RD |
952 | list_for_each_entry(transport, &asoc->peer.transport_addr_list, |
953 | transports) { | |
1da177e4 LT |
954 | |
955 | if (transport == active) | |
2317f449 | 956 | continue; |
9dbc15f0 RD |
957 | list_for_each_entry(chunk, &transport->transmitted, |
958 | transmitted_list) { | |
1da177e4 LT |
959 | if (key == chunk->subh.data_hdr->tsn) { |
960 | match = transport; | |
961 | goto out; | |
962 | } | |
963 | } | |
964 | } | |
965 | out: | |
966 | return match; | |
967 | } | |
968 | ||
969 | /* Is this the association we are looking for? */ | |
970 | struct sctp_transport *sctp_assoc_is_match(struct sctp_association *asoc, | |
4110cc25 | 971 | struct net *net, |
1da177e4 LT |
972 | const union sctp_addr *laddr, |
973 | const union sctp_addr *paddr) | |
974 | { | |
975 | struct sctp_transport *transport; | |
976 | ||
e2fccedb | 977 | if ((htons(asoc->base.bind_addr.port) == laddr->v4.sin_port) && |
4110cc25 EB |
978 | (htons(asoc->peer.port) == paddr->v4.sin_port) && |
979 | net_eq(sock_net(asoc->base.sk), net)) { | |
1da177e4 LT |
980 | transport = sctp_assoc_lookup_paddr(asoc, paddr); |
981 | if (!transport) | |
982 | goto out; | |
983 | ||
984 | if (sctp_bind_addr_match(&asoc->base.bind_addr, laddr, | |
985 | sctp_sk(asoc->base.sk))) | |
986 | goto out; | |
987 | } | |
988 | transport = NULL; | |
989 | ||
990 | out: | |
1da177e4 LT |
991 | return transport; |
992 | } | |
993 | ||
994 | /* Do delayed input processing. This is scheduled by sctp_rcv(). */ | |
c4028958 | 995 | static void sctp_assoc_bh_rcv(struct work_struct *work) |
1da177e4 | 996 | { |
c4028958 DH |
997 | struct sctp_association *asoc = |
998 | container_of(work, struct sctp_association, | |
999 | base.inqueue.immediate); | |
55e26eb9 | 1000 | struct net *net = sock_net(asoc->base.sk); |
1da177e4 LT |
1001 | struct sctp_endpoint *ep; |
1002 | struct sctp_chunk *chunk; | |
1da177e4 LT |
1003 | struct sctp_inq *inqueue; |
1004 | int state; | |
1005 | sctp_subtype_t subtype; | |
1006 | int error = 0; | |
1007 | ||
1008 | /* The association should be held so we should be safe. */ | |
1009 | ep = asoc->ep; | |
1da177e4 LT |
1010 | |
1011 | inqueue = &asoc->base.inqueue; | |
1012 | sctp_association_hold(asoc); | |
1013 | while (NULL != (chunk = sctp_inq_pop(inqueue))) { | |
1014 | state = asoc->state; | |
1015 | subtype = SCTP_ST_CHUNK(chunk->chunk_hdr->type); | |
1016 | ||
bbd0d598 VY |
1017 | /* SCTP-AUTH, Section 6.3: |
1018 | * The receiver has a list of chunk types which it expects | |
1019 | * to be received only after an AUTH-chunk. This list has | |
1020 | * been sent to the peer during the association setup. It | |
1021 | * MUST silently discard these chunks if they are not placed | |
1022 | * after an AUTH chunk in the packet. | |
1023 | */ | |
1024 | if (sctp_auth_recv_cid(subtype.chunk, asoc) && !chunk->auth) | |
1025 | continue; | |
1026 | ||
1da177e4 LT |
1027 | /* Remember where the last DATA chunk came from so we |
1028 | * know where to send the SACK. | |
1029 | */ | |
1030 | if (sctp_chunk_is_data(chunk)) | |
1031 | asoc->peer.last_data_from = chunk->transport; | |
196d6759 | 1032 | else { |
55e26eb9 | 1033 | SCTP_INC_STATS(net, SCTP_MIB_INCTRLCHUNKS); |
196d6759 MB |
1034 | asoc->stats.ictrlchunks++; |
1035 | if (chunk->chunk_hdr->type == SCTP_CID_SACK) | |
1036 | asoc->stats.isacks++; | |
1037 | } | |
1da177e4 LT |
1038 | |
1039 | if (chunk->transport) | |
e575235f | 1040 | chunk->transport->last_time_heard = ktime_get(); |
1da177e4 LT |
1041 | |
1042 | /* Run through the state machine. */ | |
55e26eb9 | 1043 | error = sctp_do_sm(net, SCTP_EVENT_T_CHUNK, subtype, |
1da177e4 LT |
1044 | state, ep, asoc, chunk, GFP_ATOMIC); |
1045 | ||
1046 | /* Check to see if the association is freed in response to | |
1047 | * the incoming chunk. If so, get out of the while loop. | |
1048 | */ | |
1049 | if (asoc->base.dead) | |
1050 | break; | |
1051 | ||
1052 | /* If there is an error on chunk, discard this packet. */ | |
1053 | if (error && chunk) | |
1054 | chunk->pdiscard = 1; | |
1055 | } | |
1056 | sctp_association_put(asoc); | |
1057 | } | |
1058 | ||
1059 | /* This routine moves an association from its old sk to a new sk. */ | |
1060 | void sctp_assoc_migrate(struct sctp_association *assoc, struct sock *newsk) | |
1061 | { | |
1062 | struct sctp_sock *newsp = sctp_sk(newsk); | |
1063 | struct sock *oldsk = assoc->base.sk; | |
1064 | ||
1065 | /* Delete the association from the old endpoint's list of | |
1066 | * associations. | |
1067 | */ | |
1068 | list_del_init(&assoc->asocs); | |
1069 | ||
1070 | /* Decrement the backlog value for a TCP-style socket. */ | |
1071 | if (sctp_style(oldsk, TCP)) | |
1072 | oldsk->sk_ack_backlog--; | |
1073 | ||
1074 | /* Release references to the old endpoint and the sock. */ | |
1075 | sctp_endpoint_put(assoc->ep); | |
1076 | sock_put(assoc->base.sk); | |
1077 | ||
1078 | /* Get a reference to the new endpoint. */ | |
1079 | assoc->ep = newsp->ep; | |
1080 | sctp_endpoint_hold(assoc->ep); | |
1081 | ||
1082 | /* Get a reference to the new sock. */ | |
1083 | assoc->base.sk = newsk; | |
1084 | sock_hold(assoc->base.sk); | |
1085 | ||
1086 | /* Add the association to the new endpoint's list of associations. */ | |
1087 | sctp_endpoint_add_asoc(newsp->ep, assoc); | |
1088 | } | |
1089 | ||
1090 | /* Update an association (possibly from unexpected COOKIE-ECHO processing). */ | |
1091 | void sctp_assoc_update(struct sctp_association *asoc, | |
1092 | struct sctp_association *new) | |
1093 | { | |
1094 | struct sctp_transport *trans; | |
1095 | struct list_head *pos, *temp; | |
1096 | ||
1097 | /* Copy in new parameters of peer. */ | |
1098 | asoc->c = new->c; | |
1099 | asoc->peer.rwnd = new->peer.rwnd; | |
1100 | asoc->peer.sack_needed = new->peer.sack_needed; | |
1be9a950 | 1101 | asoc->peer.auth_capable = new->peer.auth_capable; |
1da177e4 | 1102 | asoc->peer.i = new->peer.i; |
8e1ee18c VY |
1103 | sctp_tsnmap_init(&asoc->peer.tsn_map, SCTP_TSN_MAP_INITIAL, |
1104 | asoc->peer.i.initial_tsn, GFP_ATOMIC); | |
1da177e4 LT |
1105 | |
1106 | /* Remove any peer addresses not present in the new association. */ | |
1107 | list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) { | |
1108 | trans = list_entry(pos, struct sctp_transport, transports); | |
0c42749c VY |
1109 | if (!sctp_assoc_lookup_paddr(new, &trans->ipaddr)) { |
1110 | sctp_assoc_rm_peer(asoc, trans); | |
1111 | continue; | |
1112 | } | |
749bf921 VY |
1113 | |
1114 | if (asoc->state >= SCTP_STATE_ESTABLISHED) | |
1115 | sctp_transport_reset(trans); | |
1da177e4 LT |
1116 | } |
1117 | ||
1118 | /* If the case is A (association restart), use | |
1119 | * initial_tsn as next_tsn. If the case is B, use | |
1120 | * current next_tsn in case data sent to peer | |
1121 | * has been discarded and needs retransmission. | |
1122 | */ | |
1123 | if (asoc->state >= SCTP_STATE_ESTABLISHED) { | |
1124 | asoc->next_tsn = new->next_tsn; | |
1125 | asoc->ctsn_ack_point = new->ctsn_ack_point; | |
1126 | asoc->adv_peer_ack_point = new->adv_peer_ack_point; | |
1127 | ||
1128 | /* Reinitialize SSN for both local streams | |
1129 | * and peer's streams. | |
1130 | */ | |
1131 | sctp_ssnmap_clear(asoc->ssnmap); | |
1132 | ||
0b58a811 VY |
1133 | /* Flush the ULP reassembly and ordered queue. |
1134 | * Any data there will now be stale and will | |
1135 | * cause problems. | |
1136 | */ | |
1137 | sctp_ulpq_flush(&asoc->ulpq); | |
1138 | ||
749bf921 VY |
1139 | /* reset the overall association error count so |
1140 | * that the restarted association doesn't get torn | |
1141 | * down on the next retransmission timer. | |
1142 | */ | |
1143 | asoc->overall_error_count = 0; | |
1144 | ||
1da177e4 LT |
1145 | } else { |
1146 | /* Add any peer addresses from the new association. */ | |
9dbc15f0 RD |
1147 | list_for_each_entry(trans, &new->peer.transport_addr_list, |
1148 | transports) { | |
1da177e4 LT |
1149 | if (!sctp_assoc_lookup_paddr(asoc, &trans->ipaddr)) |
1150 | sctp_assoc_add_peer(asoc, &trans->ipaddr, | |
ad8fec17 | 1151 | GFP_ATOMIC, trans->state); |
1da177e4 LT |
1152 | } |
1153 | ||
1154 | asoc->ctsn_ack_point = asoc->next_tsn - 1; | |
1155 | asoc->adv_peer_ack_point = asoc->ctsn_ack_point; | |
1156 | if (!asoc->ssnmap) { | |
1157 | /* Move the ssnmap. */ | |
1158 | asoc->ssnmap = new->ssnmap; | |
1159 | new->ssnmap = NULL; | |
1160 | } | |
07d93967 VY |
1161 | |
1162 | if (!asoc->assoc_id) { | |
1163 | /* get a new association id since we don't have one | |
1164 | * yet. | |
1165 | */ | |
1166 | sctp_assoc_set_id(asoc, GFP_ATOMIC); | |
1167 | } | |
1da177e4 | 1168 | } |
a29a5bd4 | 1169 | |
9d2c881a | 1170 | /* SCTP-AUTH: Save the peer parameters from the new associations |
730fc3d0 VY |
1171 | * and also move the association shared keys over |
1172 | */ | |
1173 | kfree(asoc->peer.peer_random); | |
1174 | asoc->peer.peer_random = new->peer.peer_random; | |
1175 | new->peer.peer_random = NULL; | |
1176 | ||
1177 | kfree(asoc->peer.peer_chunks); | |
1178 | asoc->peer.peer_chunks = new->peer.peer_chunks; | |
1179 | new->peer.peer_chunks = NULL; | |
1180 | ||
1181 | kfree(asoc->peer.peer_hmacs); | |
1182 | asoc->peer.peer_hmacs = new->peer.peer_hmacs; | |
1183 | new->peer.peer_hmacs = NULL; | |
1184 | ||
730fc3d0 | 1185 | sctp_auth_asoc_init_active_key(asoc, GFP_ATOMIC); |
1da177e4 LT |
1186 | } |
1187 | ||
1188 | /* Update the retran path for sending a retransmitted packet. | |
4c47af4d DB |
1189 | * See also RFC4960, 6.4. Multi-Homed SCTP Endpoints: |
1190 | * | |
1191 | * When there is outbound data to send and the primary path | |
1192 | * becomes inactive (e.g., due to failures), or where the | |
1193 | * SCTP user explicitly requests to send data to an | |
1194 | * inactive destination transport address, before reporting | |
1195 | * an error to its ULP, the SCTP endpoint should try to send | |
1196 | * the data to an alternate active destination transport | |
1197 | * address if one exists. | |
1198 | * | |
1199 | * When retransmitting data that timed out, if the endpoint | |
1200 | * is multihomed, it should consider each source-destination | |
1201 | * address pair in its retransmission selection policy. | |
1202 | * When retransmitting timed-out data, the endpoint should | |
1203 | * attempt to pick the most divergent source-destination | |
1204 | * pair from the original source-destination pair to which | |
1205 | * the packet was transmitted. | |
1206 | * | |
1207 | * Note: Rules for picking the most divergent source-destination | |
1208 | * pair are an implementation decision and are not specified | |
1209 | * within this document. | |
1210 | * | |
1211 | * Our basic strategy is to round-robin transports in priorities | |
1212 | * according to sctp_state_prio_map[] e.g., if no such | |
1213 | * transport with state SCTP_ACTIVE exists, round-robin through | |
1214 | * SCTP_UNKNOWN, etc. You get the picture. | |
1da177e4 | 1215 | */ |
4c47af4d DB |
1216 | static const u8 sctp_trans_state_to_prio_map[] = { |
1217 | [SCTP_ACTIVE] = 3, /* best case */ | |
1218 | [SCTP_UNKNOWN] = 2, | |
1219 | [SCTP_PF] = 1, | |
1220 | [SCTP_INACTIVE] = 0, /* worst case */ | |
1221 | }; | |
1222 | ||
1223 | static u8 sctp_trans_score(const struct sctp_transport *trans) | |
1da177e4 | 1224 | { |
4c47af4d DB |
1225 | return sctp_trans_state_to_prio_map[trans->state]; |
1226 | } | |
1da177e4 | 1227 | |
a7288c4d DB |
1228 | static struct sctp_transport *sctp_trans_elect_tie(struct sctp_transport *trans1, |
1229 | struct sctp_transport *trans2) | |
1230 | { | |
1231 | if (trans1->error_count > trans2->error_count) { | |
1232 | return trans2; | |
1233 | } else if (trans1->error_count == trans2->error_count && | |
1234 | ktime_after(trans2->last_time_heard, | |
1235 | trans1->last_time_heard)) { | |
1236 | return trans2; | |
1237 | } else { | |
1238 | return trans1; | |
1239 | } | |
1240 | } | |
1241 | ||
4c47af4d DB |
1242 | static struct sctp_transport *sctp_trans_elect_best(struct sctp_transport *curr, |
1243 | struct sctp_transport *best) | |
1244 | { | |
a7288c4d DB |
1245 | u8 score_curr, score_best; |
1246 | ||
ea4f19c1 | 1247 | if (best == NULL || curr == best) |
4c47af4d | 1248 | return curr; |
4141ddc0 | 1249 | |
a7288c4d DB |
1250 | score_curr = sctp_trans_score(curr); |
1251 | score_best = sctp_trans_score(best); | |
1252 | ||
1253 | /* First, try a score-based selection if both transport states | |
1254 | * differ. If we're in a tie, lets try to make a more clever | |
1255 | * decision here based on error counts and last time heard. | |
1256 | */ | |
1257 | if (score_curr > score_best) | |
1258 | return curr; | |
1259 | else if (score_curr == score_best) | |
1260 | return sctp_trans_elect_tie(curr, best); | |
1261 | else | |
1262 | return best; | |
4c47af4d | 1263 | } |
1da177e4 | 1264 | |
4c47af4d DB |
1265 | void sctp_assoc_update_retran_path(struct sctp_association *asoc) |
1266 | { | |
1267 | struct sctp_transport *trans = asoc->peer.retran_path; | |
1268 | struct sctp_transport *trans_next = NULL; | |
1da177e4 | 1269 | |
4c47af4d DB |
1270 | /* We're done as we only have the one and only path. */ |
1271 | if (asoc->peer.transport_count == 1) | |
1272 | return; | |
1273 | /* If active_path and retran_path are the same and active, | |
1274 | * then this is the only active path. Use it. | |
1275 | */ | |
1276 | if (asoc->peer.active_path == asoc->peer.retran_path && | |
1277 | asoc->peer.active_path->state == SCTP_ACTIVE) | |
1278 | return; | |
1da177e4 | 1279 | |
4c47af4d DB |
1280 | /* Iterate from retran_path's successor back to retran_path. */ |
1281 | for (trans = list_next_entry(trans, transports); 1; | |
1282 | trans = list_next_entry(trans, transports)) { | |
1283 | /* Manually skip the head element. */ | |
1284 | if (&trans->transports == &asoc->peer.transport_addr_list) | |
1285 | continue; | |
1286 | if (trans->state == SCTP_UNCONFIRMED) | |
1287 | continue; | |
1288 | trans_next = sctp_trans_elect_best(trans, trans_next); | |
1289 | /* Active is good enough for immediate return. */ | |
1290 | if (trans_next->state == SCTP_ACTIVE) | |
4141ddc0 | 1291 | break; |
4c47af4d DB |
1292 | /* We've reached the end, time to update path. */ |
1293 | if (trans == asoc->peer.retran_path) | |
1da177e4 | 1294 | break; |
1da177e4 LT |
1295 | } |
1296 | ||
433131ba | 1297 | asoc->peer.retran_path = trans_next; |
3f7a87d2 | 1298 | |
4c47af4d DB |
1299 | pr_debug("%s: association:%p updated new path to addr:%pISpc\n", |
1300 | __func__, asoc, &asoc->peer.retran_path->ipaddr.sa); | |
3f7a87d2 FF |
1301 | } |
1302 | ||
b82e8f31 DB |
1303 | static void sctp_select_active_and_retran_path(struct sctp_association *asoc) |
1304 | { | |
1305 | struct sctp_transport *trans, *trans_pri = NULL, *trans_sec = NULL; | |
a7288c4d | 1306 | struct sctp_transport *trans_pf = NULL; |
b82e8f31 DB |
1307 | |
1308 | /* Look for the two most recently used active transports. */ | |
1309 | list_for_each_entry(trans, &asoc->peer.transport_addr_list, | |
1310 | transports) { | |
a7288c4d | 1311 | /* Skip uninteresting transports. */ |
b82e8f31 | 1312 | if (trans->state == SCTP_INACTIVE || |
a7288c4d | 1313 | trans->state == SCTP_UNCONFIRMED) |
b82e8f31 | 1314 | continue; |
a7288c4d DB |
1315 | /* Keep track of the best PF transport from our |
1316 | * list in case we don't find an active one. | |
1317 | */ | |
1318 | if (trans->state == SCTP_PF) { | |
1319 | trans_pf = sctp_trans_elect_best(trans, trans_pf); | |
1320 | continue; | |
1321 | } | |
1322 | /* For active transports, pick the most recent ones. */ | |
b82e8f31 | 1323 | if (trans_pri == NULL || |
e575235f DB |
1324 | ktime_after(trans->last_time_heard, |
1325 | trans_pri->last_time_heard)) { | |
b82e8f31 DB |
1326 | trans_sec = trans_pri; |
1327 | trans_pri = trans; | |
1328 | } else if (trans_sec == NULL || | |
e575235f DB |
1329 | ktime_after(trans->last_time_heard, |
1330 | trans_sec->last_time_heard)) { | |
b82e8f31 DB |
1331 | trans_sec = trans; |
1332 | } | |
1333 | } | |
1334 | ||
1335 | /* RFC 2960 6.4 Multi-Homed SCTP Endpoints | |
1336 | * | |
1337 | * By default, an endpoint should always transmit to the primary | |
1338 | * path, unless the SCTP user explicitly specifies the | |
1339 | * destination transport address (and possibly source transport | |
1340 | * address) to use. [If the primary is active but not most recent, | |
1341 | * bump the most recently used transport.] | |
1342 | */ | |
1343 | if ((asoc->peer.primary_path->state == SCTP_ACTIVE || | |
1344 | asoc->peer.primary_path->state == SCTP_UNKNOWN) && | |
1345 | asoc->peer.primary_path != trans_pri) { | |
1346 | trans_sec = trans_pri; | |
1347 | trans_pri = asoc->peer.primary_path; | |
1348 | } | |
1349 | ||
1350 | /* We did not find anything useful for a possible retransmission | |
1351 | * path; either primary path that we found is the the same as | |
1352 | * the current one, or we didn't generally find an active one. | |
1353 | */ | |
1354 | if (trans_sec == NULL) | |
1355 | trans_sec = trans_pri; | |
1356 | ||
1357 | /* If we failed to find a usable transport, just camp on the | |
aa4a83ee | 1358 | * active or pick a PF iff it's the better choice. |
b82e8f31 DB |
1359 | */ |
1360 | if (trans_pri == NULL) { | |
aa4a83ee DB |
1361 | trans_pri = sctp_trans_elect_best(asoc->peer.active_path, trans_pf); |
1362 | trans_sec = trans_pri; | |
b82e8f31 DB |
1363 | } |
1364 | ||
1365 | /* Set the active and retran transports. */ | |
1366 | asoc->peer.active_path = trans_pri; | |
1367 | asoc->peer.retran_path = trans_sec; | |
1368 | } | |
1369 | ||
4c47af4d DB |
1370 | struct sctp_transport * |
1371 | sctp_assoc_choose_alter_transport(struct sctp_association *asoc, | |
1372 | struct sctp_transport *last_sent_to) | |
3f7a87d2 | 1373 | { |
9919b455 WY |
1374 | /* If this is the first time packet is sent, use the active path, |
1375 | * else use the retran path. If the last packet was sent over the | |
3f7a87d2 FF |
1376 | * retran path, update the retran path and use it. |
1377 | */ | |
4c47af4d | 1378 | if (last_sent_to == NULL) { |
1da177e4 | 1379 | return asoc->peer.active_path; |
4c47af4d | 1380 | } else { |
9919b455 | 1381 | if (last_sent_to == asoc->peer.retran_path) |
1da177e4 | 1382 | sctp_assoc_update_retran_path(asoc); |
4c47af4d | 1383 | |
1da177e4 LT |
1384 | return asoc->peer.retran_path; |
1385 | } | |
1da177e4 LT |
1386 | } |
1387 | ||
1388 | /* Update the association's pmtu and frag_point by going through all the | |
1389 | * transports. This routine is called when a transport's PMTU has changed. | |
1390 | */ | |
02f3d4ce | 1391 | void sctp_assoc_sync_pmtu(struct sock *sk, struct sctp_association *asoc) |
1da177e4 LT |
1392 | { |
1393 | struct sctp_transport *t; | |
1da177e4 LT |
1394 | __u32 pmtu = 0; |
1395 | ||
1396 | if (!asoc) | |
1397 | return; | |
1398 | ||
1399 | /* Get the lowest pmtu of all the transports. */ | |
9dbc15f0 RD |
1400 | list_for_each_entry(t, &asoc->peer.transport_addr_list, |
1401 | transports) { | |
8a479491 | 1402 | if (t->pmtu_pending && t->dst) { |
02f3d4ce | 1403 | sctp_transport_update_pmtu(sk, t, dst_mtu(t->dst)); |
8a479491 VY |
1404 | t->pmtu_pending = 0; |
1405 | } | |
52ccb8e9 FF |
1406 | if (!pmtu || (t->pathmtu < pmtu)) |
1407 | pmtu = t->pathmtu; | |
1da177e4 LT |
1408 | } |
1409 | ||
1410 | if (pmtu) { | |
52ccb8e9 | 1411 | asoc->pathmtu = pmtu; |
f68b2e05 | 1412 | asoc->frag_point = sctp_frag_point(asoc, pmtu); |
1da177e4 LT |
1413 | } |
1414 | ||
bb33381d DB |
1415 | pr_debug("%s: asoc:%p, pmtu:%d, frag_point:%d\n", __func__, asoc, |
1416 | asoc->pathmtu, asoc->frag_point); | |
1da177e4 LT |
1417 | } |
1418 | ||
1419 | /* Should we send a SACK to update our peer? */ | |
ce4a03db | 1420 | static inline bool sctp_peer_needs_update(struct sctp_association *asoc) |
1da177e4 | 1421 | { |
e1fc3b14 | 1422 | struct net *net = sock_net(asoc->base.sk); |
1da177e4 LT |
1423 | switch (asoc->state) { |
1424 | case SCTP_STATE_ESTABLISHED: | |
1425 | case SCTP_STATE_SHUTDOWN_PENDING: | |
1426 | case SCTP_STATE_SHUTDOWN_RECEIVED: | |
1427 | case SCTP_STATE_SHUTDOWN_SENT: | |
1428 | if ((asoc->rwnd > asoc->a_rwnd) && | |
90f2f531 | 1429 | ((asoc->rwnd - asoc->a_rwnd) >= max_t(__u32, |
e1fc3b14 | 1430 | (asoc->base.sk->sk_rcvbuf >> net->sctp.rwnd_upd_shift), |
90f2f531 | 1431 | asoc->pathmtu))) |
ce4a03db | 1432 | return true; |
1da177e4 LT |
1433 | break; |
1434 | default: | |
1435 | break; | |
1436 | } | |
ce4a03db | 1437 | return false; |
1da177e4 LT |
1438 | } |
1439 | ||
362d5204 DB |
1440 | /* Increase asoc's rwnd by len and send any window update SACK if needed. */ |
1441 | void sctp_assoc_rwnd_increase(struct sctp_association *asoc, unsigned int len) | |
1da177e4 LT |
1442 | { |
1443 | struct sctp_chunk *sack; | |
1444 | struct timer_list *timer; | |
1445 | ||
362d5204 DB |
1446 | if (asoc->rwnd_over) { |
1447 | if (asoc->rwnd_over >= len) { | |
1448 | asoc->rwnd_over -= len; | |
1449 | } else { | |
1450 | asoc->rwnd += (len - asoc->rwnd_over); | |
1451 | asoc->rwnd_over = 0; | |
1452 | } | |
1453 | } else { | |
1454 | asoc->rwnd += len; | |
1455 | } | |
1da177e4 | 1456 | |
362d5204 DB |
1457 | /* If we had window pressure, start recovering it |
1458 | * once our rwnd had reached the accumulated pressure | |
1459 | * threshold. The idea is to recover slowly, but up | |
1460 | * to the initial advertised window. | |
1461 | */ | |
1462 | if (asoc->rwnd_press && asoc->rwnd >= asoc->rwnd_press) { | |
1463 | int change = min(asoc->pathmtu, asoc->rwnd_press); | |
1464 | asoc->rwnd += change; | |
1465 | asoc->rwnd_press -= change; | |
1466 | } | |
4d3c46e6 | 1467 | |
362d5204 DB |
1468 | pr_debug("%s: asoc:%p rwnd increased by %d to (%u, %u) - %u\n", |
1469 | __func__, asoc, len, asoc->rwnd, asoc->rwnd_over, | |
1470 | asoc->a_rwnd); | |
1da177e4 LT |
1471 | |
1472 | /* Send a window update SACK if the rwnd has increased by at least the | |
1473 | * minimum of the association's PMTU and half of the receive buffer. | |
1474 | * The algorithm used is similar to the one described in | |
1475 | * Section 4.2.3.3 of RFC 1122. | |
1476 | */ | |
362d5204 | 1477 | if (sctp_peer_needs_update(asoc)) { |
1da177e4 | 1478 | asoc->a_rwnd = asoc->rwnd; |
bb33381d DB |
1479 | |
1480 | pr_debug("%s: sending window update SACK- asoc:%p rwnd:%u " | |
1481 | "a_rwnd:%u\n", __func__, asoc, asoc->rwnd, | |
1482 | asoc->a_rwnd); | |
1483 | ||
1da177e4 LT |
1484 | sack = sctp_make_sack(asoc); |
1485 | if (!sack) | |
1486 | return; | |
1487 | ||
1488 | asoc->peer.sack_needed = 0; | |
1489 | ||
1490 | sctp_outq_tail(&asoc->outqueue, sack); | |
1491 | ||
1492 | /* Stop the SACK timer. */ | |
1493 | timer = &asoc->timers[SCTP_EVENT_TIMEOUT_SACK]; | |
25cc4ae9 | 1494 | if (del_timer(timer)) |
1da177e4 LT |
1495 | sctp_association_put(asoc); |
1496 | } | |
1497 | } | |
1498 | ||
362d5204 DB |
1499 | /* Decrease asoc's rwnd by len. */ |
1500 | void sctp_assoc_rwnd_decrease(struct sctp_association *asoc, unsigned int len) | |
1501 | { | |
1502 | int rx_count; | |
1503 | int over = 0; | |
1504 | ||
1505 | if (unlikely(!asoc->rwnd || asoc->rwnd_over)) | |
1506 | pr_debug("%s: association:%p has asoc->rwnd:%u, " | |
1507 | "asoc->rwnd_over:%u!\n", __func__, asoc, | |
1508 | asoc->rwnd, asoc->rwnd_over); | |
1509 | ||
1510 | if (asoc->ep->rcvbuf_policy) | |
1511 | rx_count = atomic_read(&asoc->rmem_alloc); | |
1512 | else | |
1513 | rx_count = atomic_read(&asoc->base.sk->sk_rmem_alloc); | |
1514 | ||
1515 | /* If we've reached or overflowed our receive buffer, announce | |
1516 | * a 0 rwnd if rwnd would still be positive. Store the | |
1517 | * the potential pressure overflow so that the window can be restored | |
1518 | * back to original value. | |
1519 | */ | |
1520 | if (rx_count >= asoc->base.sk->sk_rcvbuf) | |
1521 | over = 1; | |
1522 | ||
1523 | if (asoc->rwnd >= len) { | |
1524 | asoc->rwnd -= len; | |
1525 | if (over) { | |
1526 | asoc->rwnd_press += asoc->rwnd; | |
1527 | asoc->rwnd = 0; | |
1528 | } | |
1529 | } else { | |
1530 | asoc->rwnd_over = len - asoc->rwnd; | |
1531 | asoc->rwnd = 0; | |
1532 | } | |
1533 | ||
1534 | pr_debug("%s: asoc:%p rwnd decreased by %d to (%u, %u, %u)\n", | |
1535 | __func__, asoc, len, asoc->rwnd, asoc->rwnd_over, | |
1536 | asoc->rwnd_press); | |
1537 | } | |
1da177e4 LT |
1538 | |
1539 | /* Build the bind address list for the association based on info from the | |
1540 | * local endpoint and the remote peer. | |
1541 | */ | |
3182cd84 | 1542 | int sctp_assoc_set_bind_addr_from_ep(struct sctp_association *asoc, |
409b95af | 1543 | sctp_scope_t scope, gfp_t gfp) |
1da177e4 | 1544 | { |
1da177e4 LT |
1545 | int flags; |
1546 | ||
1547 | /* Use scoping rules to determine the subset of addresses from | |
1548 | * the endpoint. | |
1549 | */ | |
1da177e4 LT |
1550 | flags = (PF_INET6 == asoc->base.sk->sk_family) ? SCTP_ADDR6_ALLOWED : 0; |
1551 | if (asoc->peer.ipv4_address) | |
1552 | flags |= SCTP_ADDR4_PEERSUPP; | |
1553 | if (asoc->peer.ipv6_address) | |
1554 | flags |= SCTP_ADDR6_PEERSUPP; | |
1555 | ||
4db67e80 EB |
1556 | return sctp_bind_addr_copy(sock_net(asoc->base.sk), |
1557 | &asoc->base.bind_addr, | |
1da177e4 LT |
1558 | &asoc->ep->base.bind_addr, |
1559 | scope, gfp, flags); | |
1560 | } | |
1561 | ||
1562 | /* Build the association's bind address list from the cookie. */ | |
1563 | int sctp_assoc_set_bind_addr_from_cookie(struct sctp_association *asoc, | |
3182cd84 | 1564 | struct sctp_cookie *cookie, |
dd0fc66f | 1565 | gfp_t gfp) |
1da177e4 LT |
1566 | { |
1567 | int var_size2 = ntohs(cookie->peer_init->chunk_hdr.length); | |
1568 | int var_size3 = cookie->raw_addr_list_len; | |
1569 | __u8 *raw = (__u8 *)cookie->peer_init + var_size2; | |
1570 | ||
1571 | return sctp_raw_to_bind_addrs(&asoc->base.bind_addr, raw, var_size3, | |
1572 | asoc->ep->base.bind_addr.port, gfp); | |
1573 | } | |
1574 | ||
d808ad9a YH |
1575 | /* Lookup laddr in the bind address list of an association. */ |
1576 | int sctp_assoc_lookup_laddr(struct sctp_association *asoc, | |
1da177e4 LT |
1577 | const union sctp_addr *laddr) |
1578 | { | |
559cf710 | 1579 | int found = 0; |
1da177e4 | 1580 | |
1da177e4 LT |
1581 | if ((asoc->base.bind_addr.port == ntohs(laddr->v4.sin_port)) && |
1582 | sctp_bind_addr_match(&asoc->base.bind_addr, laddr, | |
559cf710 | 1583 | sctp_sk(asoc->base.sk))) |
1da177e4 | 1584 | found = 1; |
1da177e4 | 1585 | |
1da177e4 LT |
1586 | return found; |
1587 | } | |
07d93967 VY |
1588 | |
1589 | /* Set an association id for a given association */ | |
1590 | int sctp_assoc_set_id(struct sctp_association *asoc, gfp_t gfp) | |
1591 | { | |
9b87d465 | 1592 | bool preload = !!(gfp & __GFP_WAIT); |
94960e8c | 1593 | int ret; |
c6ba68a2 VY |
1594 | |
1595 | /* If the id is already assigned, keep it. */ | |
1596 | if (asoc->assoc_id) | |
94960e8c | 1597 | return 0; |
07d93967 | 1598 | |
94960e8c TH |
1599 | if (preload) |
1600 | idr_preload(gfp); | |
07d93967 | 1601 | spin_lock_bh(&sctp_assocs_id_lock); |
713e00a3 JL |
1602 | /* 0 is not a valid assoc_id, must be >= 1 */ |
1603 | ret = idr_alloc_cyclic(&sctp_assocs_id, asoc, 1, 0, GFP_NOWAIT); | |
07d93967 | 1604 | spin_unlock_bh(&sctp_assocs_id_lock); |
94960e8c TH |
1605 | if (preload) |
1606 | idr_preload_end(); | |
1607 | if (ret < 0) | |
1608 | return ret; | |
07d93967 | 1609 | |
94960e8c TH |
1610 | asoc->assoc_id = (sctp_assoc_t)ret; |
1611 | return 0; | |
07d93967 | 1612 | } |
a08de64d | 1613 | |
8b4472cc WY |
1614 | /* Free the ASCONF queue */ |
1615 | static void sctp_assoc_free_asconf_queue(struct sctp_association *asoc) | |
1616 | { | |
1617 | struct sctp_chunk *asconf; | |
1618 | struct sctp_chunk *tmp; | |
1619 | ||
1620 | list_for_each_entry_safe(asconf, tmp, &asoc->addip_chunk_list, list) { | |
1621 | list_del_init(&asconf->list); | |
1622 | sctp_chunk_free(asconf); | |
1623 | } | |
1624 | } | |
1625 | ||
a08de64d VY |
1626 | /* Free asconf_ack cache */ |
1627 | static void sctp_assoc_free_asconf_acks(struct sctp_association *asoc) | |
1628 | { | |
1629 | struct sctp_chunk *ack; | |
1630 | struct sctp_chunk *tmp; | |
1631 | ||
1632 | list_for_each_entry_safe(ack, tmp, &asoc->asconf_ack_list, | |
1633 | transmitted_list) { | |
1634 | list_del_init(&ack->transmitted_list); | |
1635 | sctp_chunk_free(ack); | |
1636 | } | |
1637 | } | |
1638 | ||
1639 | /* Clean up the ASCONF_ACK queue */ | |
1640 | void sctp_assoc_clean_asconf_ack_cache(const struct sctp_association *asoc) | |
1641 | { | |
1642 | struct sctp_chunk *ack; | |
1643 | struct sctp_chunk *tmp; | |
1644 | ||
25985edc | 1645 | /* We can remove all the entries from the queue up to |
a08de64d VY |
1646 | * the "Peer-Sequence-Number". |
1647 | */ | |
1648 | list_for_each_entry_safe(ack, tmp, &asoc->asconf_ack_list, | |
1649 | transmitted_list) { | |
1650 | if (ack->subh.addip_hdr->serial == | |
1651 | htonl(asoc->peer.addip_serial)) | |
1652 | break; | |
1653 | ||
1654 | list_del_init(&ack->transmitted_list); | |
1655 | sctp_chunk_free(ack); | |
1656 | } | |
1657 | } | |
1658 | ||
1659 | /* Find the ASCONF_ACK whose serial number matches ASCONF */ | |
1660 | struct sctp_chunk *sctp_assoc_lookup_asconf_ack( | |
1661 | const struct sctp_association *asoc, | |
1662 | __be32 serial) | |
1663 | { | |
a8699814 | 1664 | struct sctp_chunk *ack; |
a08de64d VY |
1665 | |
1666 | /* Walk through the list of cached ASCONF-ACKs and find the | |
1667 | * ack chunk whose serial number matches that of the request. | |
1668 | */ | |
1669 | list_for_each_entry(ack, &asoc->asconf_ack_list, transmitted_list) { | |
b69040d8 DB |
1670 | if (sctp_chunk_pending(ack)) |
1671 | continue; | |
a08de64d VY |
1672 | if (ack->subh.addip_hdr->serial == serial) { |
1673 | sctp_chunk_hold(ack); | |
a8699814 | 1674 | return ack; |
a08de64d VY |
1675 | } |
1676 | } | |
1677 | ||
a8699814 | 1678 | return NULL; |
a08de64d | 1679 | } |
a000c01e WY |
1680 | |
1681 | void sctp_asconf_queue_teardown(struct sctp_association *asoc) | |
1682 | { | |
1683 | /* Free any cached ASCONF_ACK chunk. */ | |
1684 | sctp_assoc_free_asconf_acks(asoc); | |
1685 | ||
1686 | /* Free the ASCONF queue. */ | |
1687 | sctp_assoc_free_asconf_queue(asoc); | |
1688 | ||
1689 | /* Free any cached ASCONF chunk. */ | |
1690 | if (asoc->addip_last_asconf) | |
1691 | sctp_chunk_free(asoc->addip_last_asconf); | |
1692 | } |