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1da177e4 LT |
1 | /* SCTP kernel reference Implementation |
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 | * | |
8 | * This file is part of the SCTP kernel reference Implementation | |
9 | * | |
10 | * This module provides the abstraction for an SCTP association. | |
11 | * | |
12 | * The SCTP reference implementation is free software; | |
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 | * | |
18 | * The SCTP reference implementation is distributed in the hope that it | |
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 | |
25 | * along with GNU CC; see the file COPYING. If not, write to | |
26 | * the Free Software Foundation, 59 Temple Place - Suite 330, | |
27 | * Boston, MA 02111-1307, USA. | |
28 | * | |
29 | * Please send any bug reports or fixes you make to the | |
30 | * email address(es): | |
31 | * lksctp developers <lksctp-developers@lists.sourceforge.net> | |
32 | * | |
33 | * Or submit a bug report through the following website: | |
34 | * http://www.sf.net/projects/lksctp | |
35 | * | |
36 | * Written or modified by: | |
37 | * La Monte H.P. Yarroll <piggy@acm.org> | |
38 | * Karl Knutson <karl@athena.chicago.il.us> | |
39 | * Jon Grimm <jgrimm@us.ibm.com> | |
40 | * Xingang Guo <xingang.guo@intel.com> | |
41 | * Hui Huang <hui.huang@nokia.com> | |
42 | * Sridhar Samudrala <sri@us.ibm.com> | |
43 | * Daisy Chang <daisyc@us.ibm.com> | |
44 | * Ryan Layer <rmlayer@us.ibm.com> | |
45 | * Kevin Gao <kevin.gao@intel.com> | |
46 | * | |
47 | * Any bugs reported given to us we will try to fix... any fixes shared will | |
48 | * be incorporated into the next SCTP release. | |
49 | */ | |
50 | ||
51 | #include <linux/types.h> | |
52 | #include <linux/fcntl.h> | |
53 | #include <linux/poll.h> | |
54 | #include <linux/init.h> | |
1da177e4 LT |
55 | |
56 | #include <linux/slab.h> | |
57 | #include <linux/in.h> | |
58 | #include <net/ipv6.h> | |
59 | #include <net/sctp/sctp.h> | |
60 | #include <net/sctp/sm.h> | |
61 | ||
62 | /* Forward declarations for internal functions. */ | |
c4028958 | 63 | static void sctp_assoc_bh_rcv(struct work_struct *work); |
1da177e4 LT |
64 | |
65 | ||
66 | /* 1st Level Abstractions. */ | |
67 | ||
68 | /* Initialize a new association from provided memory. */ | |
69 | static struct sctp_association *sctp_association_init(struct sctp_association *asoc, | |
70 | const struct sctp_endpoint *ep, | |
71 | const struct sock *sk, | |
72 | sctp_scope_t scope, | |
dd0fc66f | 73 | gfp_t gfp) |
1da177e4 LT |
74 | { |
75 | struct sctp_sock *sp; | |
76 | int i; | |
77 | ||
78 | /* Retrieve the SCTP per socket area. */ | |
79 | sp = sctp_sk((struct sock *)sk); | |
80 | ||
81 | /* Init all variables to a known value. */ | |
82 | memset(asoc, 0, sizeof(struct sctp_association)); | |
83 | ||
84 | /* Discarding const is appropriate here. */ | |
85 | asoc->ep = (struct sctp_endpoint *)ep; | |
86 | sctp_endpoint_hold(asoc->ep); | |
87 | ||
88 | /* Hold the sock. */ | |
89 | asoc->base.sk = (struct sock *)sk; | |
90 | sock_hold(asoc->base.sk); | |
91 | ||
92 | /* Initialize the common base substructure. */ | |
93 | asoc->base.type = SCTP_EP_TYPE_ASSOCIATION; | |
94 | ||
95 | /* Initialize the object handling fields. */ | |
96 | atomic_set(&asoc->base.refcnt, 1); | |
97 | asoc->base.dead = 0; | |
98 | asoc->base.malloced = 0; | |
99 | ||
100 | /* Initialize the bind addr area. */ | |
101 | sctp_bind_addr_init(&asoc->base.bind_addr, ep->base.bind_addr.port); | |
102 | rwlock_init(&asoc->base.addr_lock); | |
103 | ||
104 | asoc->state = SCTP_STATE_CLOSED; | |
105 | ||
106 | /* Set these values from the socket values, a conversion between | |
107 | * millsecons to seconds/microseconds must also be done. | |
108 | */ | |
109 | asoc->cookie_life.tv_sec = sp->assocparams.sasoc_cookie_life / 1000; | |
110 | asoc->cookie_life.tv_usec = (sp->assocparams.sasoc_cookie_life % 1000) | |
111 | * 1000; | |
1da177e4 LT |
112 | asoc->frag_point = 0; |
113 | ||
114 | /* Set the association max_retrans and RTO values from the | |
115 | * socket values. | |
116 | */ | |
117 | asoc->max_retrans = sp->assocparams.sasoc_asocmaxrxt; | |
118 | asoc->rto_initial = msecs_to_jiffies(sp->rtoinfo.srto_initial); | |
119 | asoc->rto_max = msecs_to_jiffies(sp->rtoinfo.srto_max); | |
120 | asoc->rto_min = msecs_to_jiffies(sp->rtoinfo.srto_min); | |
121 | ||
122 | asoc->overall_error_count = 0; | |
123 | ||
52ccb8e9 FF |
124 | /* Initialize the association's heartbeat interval based on the |
125 | * sock configured value. | |
126 | */ | |
127 | asoc->hbinterval = msecs_to_jiffies(sp->hbinterval); | |
128 | ||
129 | /* Initialize path max retrans value. */ | |
130 | asoc->pathmaxrxt = sp->pathmaxrxt; | |
131 | ||
132 | /* Initialize default path MTU. */ | |
133 | asoc->pathmtu = sp->pathmtu; | |
134 | ||
135 | /* Set association default SACK delay */ | |
136 | asoc->sackdelay = msecs_to_jiffies(sp->sackdelay); | |
137 | ||
138 | /* Set the association default flags controlling | |
139 | * Heartbeat, SACK delay, and Path MTU Discovery. | |
140 | */ | |
141 | asoc->param_flags = sp->param_flags; | |
142 | ||
1da177e4 LT |
143 | /* Initialize the maximum mumber of new data packets that can be sent |
144 | * in a burst. | |
145 | */ | |
146 | asoc->max_burst = sctp_max_burst; | |
147 | ||
1e7d3d90 VY |
148 | /* initialize association timers */ |
149 | asoc->timeouts[SCTP_EVENT_TIMEOUT_NONE] = 0; | |
150 | asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_COOKIE] = asoc->rto_initial; | |
151 | asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_INIT] = asoc->rto_initial; | |
152 | asoc->timeouts[SCTP_EVENT_TIMEOUT_T2_SHUTDOWN] = asoc->rto_initial; | |
153 | asoc->timeouts[SCTP_EVENT_TIMEOUT_T3_RTX] = 0; | |
154 | asoc->timeouts[SCTP_EVENT_TIMEOUT_T4_RTO] = 0; | |
155 | ||
156 | /* sctpimpguide Section 2.12.2 | |
157 | * If the 'T5-shutdown-guard' timer is used, it SHOULD be set to the | |
158 | * recommended value of 5 times 'RTO.Max'. | |
159 | */ | |
d808ad9a | 160 | asoc->timeouts[SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD] |
1e7d3d90 VY |
161 | = 5 * asoc->rto_max; |
162 | ||
163 | asoc->timeouts[SCTP_EVENT_TIMEOUT_HEARTBEAT] = 0; | |
52ccb8e9 | 164 | asoc->timeouts[SCTP_EVENT_TIMEOUT_SACK] = asoc->sackdelay; |
1e7d3d90 VY |
165 | asoc->timeouts[SCTP_EVENT_TIMEOUT_AUTOCLOSE] = |
166 | sp->autoclose * HZ; | |
d808ad9a | 167 | |
1e7d3d90 | 168 | /* Initilizes the timers */ |
1da177e4 | 169 | for (i = SCTP_EVENT_TIMEOUT_NONE; i < SCTP_NUM_TIMEOUT_TYPES; ++i) { |
1da177e4 LT |
170 | init_timer(&asoc->timers[i]); |
171 | asoc->timers[i].function = sctp_timer_events[i]; | |
172 | asoc->timers[i].data = (unsigned long) asoc; | |
173 | } | |
174 | ||
175 | /* Pull default initialization values from the sock options. | |
176 | * Note: This assumes that the values have already been | |
177 | * validated in the sock. | |
178 | */ | |
179 | asoc->c.sinit_max_instreams = sp->initmsg.sinit_max_instreams; | |
180 | asoc->c.sinit_num_ostreams = sp->initmsg.sinit_num_ostreams; | |
181 | asoc->max_init_attempts = sp->initmsg.sinit_max_attempts; | |
182 | ||
183 | asoc->max_init_timeo = | |
184 | msecs_to_jiffies(sp->initmsg.sinit_max_init_timeo); | |
185 | ||
186 | /* Allocate storage for the ssnmap after the inbound and outbound | |
187 | * streams have been negotiated during Init. | |
188 | */ | |
189 | asoc->ssnmap = NULL; | |
190 | ||
191 | /* Set the local window size for receive. | |
192 | * This is also the rcvbuf space per association. | |
193 | * RFC 6 - A SCTP receiver MUST be able to receive a minimum of | |
194 | * 1500 bytes in one SCTP packet. | |
195 | */ | |
049b3ff5 | 196 | if ((sk->sk_rcvbuf/2) < SCTP_DEFAULT_MINWINDOW) |
1da177e4 LT |
197 | asoc->rwnd = SCTP_DEFAULT_MINWINDOW; |
198 | else | |
049b3ff5 | 199 | asoc->rwnd = sk->sk_rcvbuf/2; |
1da177e4 LT |
200 | |
201 | asoc->a_rwnd = asoc->rwnd; | |
202 | ||
203 | asoc->rwnd_over = 0; | |
204 | ||
205 | /* Use my own max window until I learn something better. */ | |
206 | asoc->peer.rwnd = SCTP_DEFAULT_MAXWINDOW; | |
207 | ||
208 | /* Set the sndbuf size for transmit. */ | |
209 | asoc->sndbuf_used = 0; | |
210 | ||
049b3ff5 NH |
211 | /* Initialize the receive memory counter */ |
212 | atomic_set(&asoc->rmem_alloc, 0); | |
213 | ||
1da177e4 LT |
214 | init_waitqueue_head(&asoc->wait); |
215 | ||
216 | asoc->c.my_vtag = sctp_generate_tag(ep); | |
217 | asoc->peer.i.init_tag = 0; /* INIT needs a vtag of 0. */ | |
218 | asoc->c.peer_vtag = 0; | |
219 | asoc->c.my_ttag = 0; | |
220 | asoc->c.peer_ttag = 0; | |
221 | asoc->c.my_port = ep->base.bind_addr.port; | |
222 | ||
223 | asoc->c.initial_tsn = sctp_generate_tsn(ep); | |
224 | ||
225 | asoc->next_tsn = asoc->c.initial_tsn; | |
226 | ||
227 | asoc->ctsn_ack_point = asoc->next_tsn - 1; | |
228 | asoc->adv_peer_ack_point = asoc->ctsn_ack_point; | |
229 | asoc->highest_sacked = asoc->ctsn_ack_point; | |
230 | asoc->last_cwr_tsn = asoc->ctsn_ack_point; | |
231 | asoc->unack_data = 0; | |
232 | ||
1da177e4 LT |
233 | /* ADDIP Section 4.1 Asconf Chunk Procedures |
234 | * | |
235 | * When an endpoint has an ASCONF signaled change to be sent to the | |
236 | * remote endpoint it should do the following: | |
237 | * ... | |
238 | * A2) a serial number should be assigned to the chunk. The serial | |
239 | * number SHOULD be a monotonically increasing number. The serial | |
240 | * numbers SHOULD be initialized at the start of the | |
241 | * association to the same value as the initial TSN. | |
242 | */ | |
243 | asoc->addip_serial = asoc->c.initial_tsn; | |
244 | ||
79af02c2 | 245 | INIT_LIST_HEAD(&asoc->addip_chunk_list); |
1da177e4 LT |
246 | |
247 | /* Make an empty list of remote transport addresses. */ | |
248 | INIT_LIST_HEAD(&asoc->peer.transport_addr_list); | |
3f7a87d2 | 249 | asoc->peer.transport_count = 0; |
1da177e4 LT |
250 | |
251 | /* RFC 2960 5.1 Normal Establishment of an Association | |
252 | * | |
253 | * After the reception of the first data chunk in an | |
254 | * association the endpoint must immediately respond with a | |
255 | * sack to acknowledge the data chunk. Subsequent | |
256 | * acknowledgements should be done as described in Section | |
257 | * 6.2. | |
258 | * | |
259 | * [We implement this by telling a new association that it | |
260 | * already received one packet.] | |
261 | */ | |
262 | asoc->peer.sack_needed = 1; | |
263 | ||
264 | /* Assume that the peer recongizes ASCONF until reported otherwise | |
265 | * via an ERROR chunk. | |
266 | */ | |
267 | asoc->peer.asconf_capable = 1; | |
268 | ||
269 | /* Create an input queue. */ | |
270 | sctp_inq_init(&asoc->base.inqueue); | |
c4028958 | 271 | sctp_inq_set_th_handler(&asoc->base.inqueue, sctp_assoc_bh_rcv); |
1da177e4 LT |
272 | |
273 | /* Create an output queue. */ | |
274 | sctp_outq_init(asoc, &asoc->outqueue); | |
275 | ||
276 | if (!sctp_ulpq_init(&asoc->ulpq, asoc)) | |
277 | goto fail_init; | |
278 | ||
279 | /* Set up the tsn tracking. */ | |
280 | sctp_tsnmap_init(&asoc->peer.tsn_map, SCTP_TSN_MAP_SIZE, 0); | |
281 | ||
282 | asoc->need_ecne = 0; | |
283 | ||
284 | asoc->assoc_id = 0; | |
285 | ||
286 | /* Assume that peer would support both address types unless we are | |
287 | * told otherwise. | |
288 | */ | |
289 | asoc->peer.ipv4_address = 1; | |
290 | asoc->peer.ipv6_address = 1; | |
291 | INIT_LIST_HEAD(&asoc->asocs); | |
292 | ||
293 | asoc->autoclose = sp->autoclose; | |
294 | ||
295 | asoc->default_stream = sp->default_stream; | |
296 | asoc->default_ppid = sp->default_ppid; | |
297 | asoc->default_flags = sp->default_flags; | |
298 | asoc->default_context = sp->default_context; | |
299 | asoc->default_timetolive = sp->default_timetolive; | |
6ab792f5 | 300 | asoc->default_rcv_context = sp->default_rcv_context; |
1da177e4 LT |
301 | |
302 | return asoc; | |
303 | ||
304 | fail_init: | |
305 | sctp_endpoint_put(asoc->ep); | |
306 | sock_put(asoc->base.sk); | |
307 | return NULL; | |
308 | } | |
309 | ||
310 | /* Allocate and initialize a new association */ | |
311 | struct sctp_association *sctp_association_new(const struct sctp_endpoint *ep, | |
312 | const struct sock *sk, | |
3182cd84 | 313 | sctp_scope_t scope, |
dd0fc66f | 314 | gfp_t gfp) |
1da177e4 LT |
315 | { |
316 | struct sctp_association *asoc; | |
317 | ||
318 | asoc = t_new(struct sctp_association, gfp); | |
319 | if (!asoc) | |
320 | goto fail; | |
321 | ||
322 | if (!sctp_association_init(asoc, ep, sk, scope, gfp)) | |
323 | goto fail_init; | |
324 | ||
325 | asoc->base.malloced = 1; | |
326 | SCTP_DBG_OBJCNT_INC(assoc); | |
3f7a87d2 | 327 | SCTP_DEBUG_PRINTK("Created asoc %p\n", asoc); |
1da177e4 LT |
328 | |
329 | return asoc; | |
330 | ||
331 | fail_init: | |
332 | kfree(asoc); | |
333 | fail: | |
334 | return NULL; | |
335 | } | |
336 | ||
337 | /* Free this association if possible. There may still be users, so | |
338 | * the actual deallocation may be delayed. | |
339 | */ | |
340 | void sctp_association_free(struct sctp_association *asoc) | |
341 | { | |
342 | struct sock *sk = asoc->base.sk; | |
343 | struct sctp_transport *transport; | |
344 | struct list_head *pos, *temp; | |
345 | int i; | |
346 | ||
de76e695 VY |
347 | /* Only real associations count against the endpoint, so |
348 | * don't bother for if this is a temporary association. | |
349 | */ | |
350 | if (!asoc->temp) { | |
351 | list_del(&asoc->asocs); | |
352 | ||
353 | /* Decrement the backlog value for a TCP-style listening | |
354 | * socket. | |
355 | */ | |
356 | if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING)) | |
357 | sk->sk_ack_backlog--; | |
358 | } | |
1da177e4 LT |
359 | |
360 | /* Mark as dead, so other users can know this structure is | |
361 | * going away. | |
362 | */ | |
363 | asoc->base.dead = 1; | |
364 | ||
365 | /* Dispose of any data lying around in the outqueue. */ | |
366 | sctp_outq_free(&asoc->outqueue); | |
367 | ||
368 | /* Dispose of any pending messages for the upper layer. */ | |
369 | sctp_ulpq_free(&asoc->ulpq); | |
370 | ||
371 | /* Dispose of any pending chunks on the inqueue. */ | |
372 | sctp_inq_free(&asoc->base.inqueue); | |
373 | ||
374 | /* Free ssnmap storage. */ | |
375 | sctp_ssnmap_free(asoc->ssnmap); | |
376 | ||
377 | /* Clean up the bound address list. */ | |
378 | sctp_bind_addr_free(&asoc->base.bind_addr); | |
379 | ||
380 | /* Do we need to go through all of our timers and | |
381 | * delete them? To be safe we will try to delete all, but we | |
382 | * should be able to go through and make a guess based | |
383 | * on our state. | |
384 | */ | |
385 | for (i = SCTP_EVENT_TIMEOUT_NONE; i < SCTP_NUM_TIMEOUT_TYPES; ++i) { | |
386 | if (timer_pending(&asoc->timers[i]) && | |
387 | del_timer(&asoc->timers[i])) | |
388 | sctp_association_put(asoc); | |
389 | } | |
390 | ||
391 | /* Free peer's cached cookie. */ | |
a51482bd | 392 | kfree(asoc->peer.cookie); |
1da177e4 LT |
393 | |
394 | /* Release the transport structures. */ | |
395 | list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) { | |
396 | transport = list_entry(pos, struct sctp_transport, transports); | |
397 | list_del(pos); | |
398 | sctp_transport_free(transport); | |
399 | } | |
400 | ||
3f7a87d2 FF |
401 | asoc->peer.transport_count = 0; |
402 | ||
1da177e4 LT |
403 | /* Free any cached ASCONF_ACK chunk. */ |
404 | if (asoc->addip_last_asconf_ack) | |
405 | sctp_chunk_free(asoc->addip_last_asconf_ack); | |
406 | ||
407 | /* Free any cached ASCONF chunk. */ | |
408 | if (asoc->addip_last_asconf) | |
409 | sctp_chunk_free(asoc->addip_last_asconf); | |
410 | ||
411 | sctp_association_put(asoc); | |
412 | } | |
413 | ||
414 | /* Cleanup and free up an association. */ | |
415 | static void sctp_association_destroy(struct sctp_association *asoc) | |
416 | { | |
417 | SCTP_ASSERT(asoc->base.dead, "Assoc is not dead", return); | |
418 | ||
419 | sctp_endpoint_put(asoc->ep); | |
420 | sock_put(asoc->base.sk); | |
421 | ||
422 | if (asoc->assoc_id != 0) { | |
423 | spin_lock_bh(&sctp_assocs_id_lock); | |
424 | idr_remove(&sctp_assocs_id, asoc->assoc_id); | |
425 | spin_unlock_bh(&sctp_assocs_id_lock); | |
426 | } | |
427 | ||
049b3ff5 NH |
428 | BUG_TRAP(!atomic_read(&asoc->rmem_alloc)); |
429 | ||
1da177e4 LT |
430 | if (asoc->base.malloced) { |
431 | kfree(asoc); | |
432 | SCTP_DBG_OBJCNT_DEC(assoc); | |
433 | } | |
434 | } | |
435 | ||
436 | /* Change the primary destination address for the peer. */ | |
437 | void sctp_assoc_set_primary(struct sctp_association *asoc, | |
438 | struct sctp_transport *transport) | |
439 | { | |
440 | asoc->peer.primary_path = transport; | |
441 | ||
442 | /* Set a default msg_name for events. */ | |
443 | memcpy(&asoc->peer.primary_addr, &transport->ipaddr, | |
444 | sizeof(union sctp_addr)); | |
445 | ||
446 | /* If the primary path is changing, assume that the | |
447 | * user wants to use this new path. | |
448 | */ | |
ad8fec17 SS |
449 | if ((transport->state == SCTP_ACTIVE) || |
450 | (transport->state == SCTP_UNKNOWN)) | |
1da177e4 LT |
451 | asoc->peer.active_path = transport; |
452 | ||
453 | /* | |
454 | * SFR-CACC algorithm: | |
455 | * Upon the receipt of a request to change the primary | |
456 | * destination address, on the data structure for the new | |
457 | * primary destination, the sender MUST do the following: | |
458 | * | |
459 | * 1) If CHANGEOVER_ACTIVE is set, then there was a switch | |
460 | * to this destination address earlier. The sender MUST set | |
461 | * CYCLING_CHANGEOVER to indicate that this switch is a | |
462 | * double switch to the same destination address. | |
463 | */ | |
464 | if (transport->cacc.changeover_active) | |
465 | transport->cacc.cycling_changeover = 1; | |
466 | ||
467 | /* 2) The sender MUST set CHANGEOVER_ACTIVE to indicate that | |
468 | * a changeover has occurred. | |
469 | */ | |
470 | transport->cacc.changeover_active = 1; | |
471 | ||
472 | /* 3) The sender MUST store the next TSN to be sent in | |
473 | * next_tsn_at_change. | |
474 | */ | |
475 | transport->cacc.next_tsn_at_change = asoc->next_tsn; | |
476 | } | |
477 | ||
3f7a87d2 FF |
478 | /* Remove a transport from an association. */ |
479 | void sctp_assoc_rm_peer(struct sctp_association *asoc, | |
480 | struct sctp_transport *peer) | |
481 | { | |
482 | struct list_head *pos; | |
483 | struct sctp_transport *transport; | |
484 | ||
485 | SCTP_DEBUG_PRINTK_IPADDR("sctp_assoc_rm_peer:association %p addr: ", | |
486 | " port: %d\n", | |
487 | asoc, | |
488 | (&peer->ipaddr), | |
b3f5b3b6 | 489 | ntohs(peer->ipaddr.v4.sin_port)); |
3f7a87d2 FF |
490 | |
491 | /* If we are to remove the current retran_path, update it | |
492 | * to the next peer before removing this peer from the list. | |
493 | */ | |
494 | if (asoc->peer.retran_path == peer) | |
495 | sctp_assoc_update_retran_path(asoc); | |
496 | ||
497 | /* Remove this peer from the list. */ | |
498 | list_del(&peer->transports); | |
499 | ||
500 | /* Get the first transport of asoc. */ | |
501 | pos = asoc->peer.transport_addr_list.next; | |
502 | transport = list_entry(pos, struct sctp_transport, transports); | |
503 | ||
504 | /* Update any entries that match the peer to be deleted. */ | |
505 | if (asoc->peer.primary_path == peer) | |
506 | sctp_assoc_set_primary(asoc, transport); | |
507 | if (asoc->peer.active_path == peer) | |
508 | asoc->peer.active_path = transport; | |
509 | if (asoc->peer.last_data_from == peer) | |
510 | asoc->peer.last_data_from = transport; | |
511 | ||
512 | /* If we remove the transport an INIT was last sent to, set it to | |
513 | * NULL. Combined with the update of the retran path above, this | |
514 | * will cause the next INIT to be sent to the next available | |
515 | * transport, maintaining the cycle. | |
516 | */ | |
517 | if (asoc->init_last_sent_to == peer) | |
518 | asoc->init_last_sent_to = NULL; | |
519 | ||
520 | asoc->peer.transport_count--; | |
521 | ||
522 | sctp_transport_free(peer); | |
523 | } | |
524 | ||
1da177e4 LT |
525 | /* Add a transport address to an association. */ |
526 | struct sctp_transport *sctp_assoc_add_peer(struct sctp_association *asoc, | |
527 | const union sctp_addr *addr, | |
dd0fc66f | 528 | const gfp_t gfp, |
3f7a87d2 | 529 | const int peer_state) |
1da177e4 LT |
530 | { |
531 | struct sctp_transport *peer; | |
532 | struct sctp_sock *sp; | |
533 | unsigned short port; | |
534 | ||
535 | sp = sctp_sk(asoc->base.sk); | |
536 | ||
537 | /* AF_INET and AF_INET6 share common port field. */ | |
4bdf4b5f | 538 | port = ntohs(addr->v4.sin_port); |
1da177e4 | 539 | |
3f7a87d2 | 540 | SCTP_DEBUG_PRINTK_IPADDR("sctp_assoc_add_peer:association %p addr: ", |
ad8fec17 | 541 | " port: %d state:%d\n", |
3f7a87d2 FF |
542 | asoc, |
543 | addr, | |
4bdf4b5f | 544 | port, |
ad8fec17 | 545 | peer_state); |
3f7a87d2 | 546 | |
1da177e4 LT |
547 | /* Set the port if it has not been set yet. */ |
548 | if (0 == asoc->peer.port) | |
549 | asoc->peer.port = port; | |
550 | ||
551 | /* Check to see if this is a duplicate. */ | |
552 | peer = sctp_assoc_lookup_paddr(asoc, addr); | |
3f7a87d2 | 553 | if (peer) { |
ad8fec17 SS |
554 | if (peer->state == SCTP_UNKNOWN) { |
555 | if (peer_state == SCTP_ACTIVE) | |
556 | peer->state = SCTP_ACTIVE; | |
557 | if (peer_state == SCTP_UNCONFIRMED) | |
558 | peer->state = SCTP_UNCONFIRMED; | |
559 | } | |
1da177e4 | 560 | return peer; |
3f7a87d2 | 561 | } |
1da177e4 LT |
562 | |
563 | peer = sctp_transport_new(addr, gfp); | |
564 | if (!peer) | |
565 | return NULL; | |
566 | ||
567 | sctp_transport_set_owner(peer, asoc); | |
568 | ||
52ccb8e9 FF |
569 | /* Initialize the peer's heartbeat interval based on the |
570 | * association configured value. | |
571 | */ | |
572 | peer->hbinterval = asoc->hbinterval; | |
573 | ||
574 | /* Set the path max_retrans. */ | |
575 | peer->pathmaxrxt = asoc->pathmaxrxt; | |
576 | ||
577 | /* Initialize the peer's SACK delay timeout based on the | |
578 | * association configured value. | |
579 | */ | |
580 | peer->sackdelay = asoc->sackdelay; | |
581 | ||
582 | /* Enable/disable heartbeat, SACK delay, and path MTU discovery | |
583 | * based on association setting. | |
584 | */ | |
585 | peer->param_flags = asoc->param_flags; | |
586 | ||
1da177e4 | 587 | /* Initialize the pmtu of the transport. */ |
52ccb8e9 FF |
588 | if (peer->param_flags & SPP_PMTUD_ENABLE) |
589 | sctp_transport_pmtu(peer); | |
590 | else if (asoc->pathmtu) | |
591 | peer->pathmtu = asoc->pathmtu; | |
592 | else | |
593 | peer->pathmtu = SCTP_DEFAULT_MAXSEGMENT; | |
1da177e4 LT |
594 | |
595 | /* If this is the first transport addr on this association, | |
596 | * initialize the association PMTU to the peer's PMTU. | |
597 | * If not and the current association PMTU is higher than the new | |
598 | * peer's PMTU, reset the association PMTU to the new peer's PMTU. | |
599 | */ | |
52ccb8e9 FF |
600 | if (asoc->pathmtu) |
601 | asoc->pathmtu = min_t(int, peer->pathmtu, asoc->pathmtu); | |
1da177e4 | 602 | else |
52ccb8e9 | 603 | asoc->pathmtu = peer->pathmtu; |
1da177e4 LT |
604 | |
605 | SCTP_DEBUG_PRINTK("sctp_assoc_add_peer:association %p PMTU set to " | |
52ccb8e9 | 606 | "%d\n", asoc, asoc->pathmtu); |
1da177e4 | 607 | |
52ccb8e9 | 608 | asoc->frag_point = sctp_frag_point(sp, asoc->pathmtu); |
1da177e4 LT |
609 | |
610 | /* The asoc->peer.port might not be meaningful yet, but | |
611 | * initialize the packet structure anyway. | |
612 | */ | |
613 | sctp_packet_init(&peer->packet, peer, asoc->base.bind_addr.port, | |
614 | asoc->peer.port); | |
615 | ||
616 | /* 7.2.1 Slow-Start | |
617 | * | |
618 | * o The initial cwnd before DATA transmission or after a sufficiently | |
619 | * long idle period MUST be set to | |
620 | * min(4*MTU, max(2*MTU, 4380 bytes)) | |
621 | * | |
622 | * o The initial value of ssthresh MAY be arbitrarily high | |
623 | * (for example, implementations MAY use the size of the | |
624 | * receiver advertised window). | |
625 | */ | |
52ccb8e9 | 626 | peer->cwnd = min(4*asoc->pathmtu, max_t(__u32, 2*asoc->pathmtu, 4380)); |
1da177e4 LT |
627 | |
628 | /* At this point, we may not have the receiver's advertised window, | |
629 | * so initialize ssthresh to the default value and it will be set | |
630 | * later when we process the INIT. | |
631 | */ | |
632 | peer->ssthresh = SCTP_DEFAULT_MAXWINDOW; | |
633 | ||
634 | peer->partial_bytes_acked = 0; | |
635 | peer->flight_size = 0; | |
636 | ||
1da177e4 LT |
637 | /* Set the transport's RTO.initial value */ |
638 | peer->rto = asoc->rto_initial; | |
639 | ||
3f7a87d2 FF |
640 | /* Set the peer's active state. */ |
641 | peer->state = peer_state; | |
642 | ||
1da177e4 LT |
643 | /* Attach the remote transport to our asoc. */ |
644 | list_add_tail(&peer->transports, &asoc->peer.transport_addr_list); | |
3f7a87d2 | 645 | asoc->peer.transport_count++; |
1da177e4 LT |
646 | |
647 | /* If we do not yet have a primary path, set one. */ | |
648 | if (!asoc->peer.primary_path) { | |
649 | sctp_assoc_set_primary(asoc, peer); | |
650 | asoc->peer.retran_path = peer; | |
651 | } | |
652 | ||
3f7a87d2 | 653 | if (asoc->peer.active_path == asoc->peer.retran_path) { |
1da177e4 | 654 | asoc->peer.retran_path = peer; |
3f7a87d2 | 655 | } |
1da177e4 LT |
656 | |
657 | return peer; | |
658 | } | |
659 | ||
660 | /* Delete a transport address from an association. */ | |
661 | void sctp_assoc_del_peer(struct sctp_association *asoc, | |
662 | const union sctp_addr *addr) | |
663 | { | |
664 | struct list_head *pos; | |
665 | struct list_head *temp; | |
1da177e4 LT |
666 | struct sctp_transport *transport; |
667 | ||
668 | list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) { | |
669 | transport = list_entry(pos, struct sctp_transport, transports); | |
670 | if (sctp_cmp_addr_exact(addr, &transport->ipaddr)) { | |
3f7a87d2 FF |
671 | /* Do book keeping for removing the peer and free it. */ |
672 | sctp_assoc_rm_peer(asoc, transport); | |
1da177e4 LT |
673 | break; |
674 | } | |
675 | } | |
1da177e4 LT |
676 | } |
677 | ||
678 | /* Lookup a transport by address. */ | |
679 | struct sctp_transport *sctp_assoc_lookup_paddr( | |
680 | const struct sctp_association *asoc, | |
681 | const union sctp_addr *address) | |
682 | { | |
683 | struct sctp_transport *t; | |
684 | struct list_head *pos; | |
685 | ||
686 | /* Cycle through all transports searching for a peer address. */ | |
687 | ||
688 | list_for_each(pos, &asoc->peer.transport_addr_list) { | |
689 | t = list_entry(pos, struct sctp_transport, transports); | |
690 | if (sctp_cmp_addr_exact(address, &t->ipaddr)) | |
691 | return t; | |
692 | } | |
693 | ||
694 | return NULL; | |
695 | } | |
696 | ||
697 | /* Engage in transport control operations. | |
698 | * Mark the transport up or down and send a notification to the user. | |
699 | * Select and update the new active and retran paths. | |
700 | */ | |
701 | void sctp_assoc_control_transport(struct sctp_association *asoc, | |
702 | struct sctp_transport *transport, | |
703 | sctp_transport_cmd_t command, | |
704 | sctp_sn_error_t error) | |
705 | { | |
706 | struct sctp_transport *t = NULL; | |
707 | struct sctp_transport *first; | |
708 | struct sctp_transport *second; | |
709 | struct sctp_ulpevent *event; | |
0906e20f | 710 | struct sockaddr_storage addr; |
1da177e4 LT |
711 | struct list_head *pos; |
712 | int spc_state = 0; | |
713 | ||
714 | /* Record the transition on the transport. */ | |
715 | switch (command) { | |
716 | case SCTP_TRANSPORT_UP: | |
3f7a87d2 | 717 | transport->state = SCTP_ACTIVE; |
1da177e4 LT |
718 | spc_state = SCTP_ADDR_AVAILABLE; |
719 | break; | |
720 | ||
721 | case SCTP_TRANSPORT_DOWN: | |
3f7a87d2 | 722 | transport->state = SCTP_INACTIVE; |
1da177e4 LT |
723 | spc_state = SCTP_ADDR_UNREACHABLE; |
724 | break; | |
725 | ||
726 | default: | |
727 | return; | |
728 | }; | |
729 | ||
730 | /* Generate and send a SCTP_PEER_ADDR_CHANGE notification to the | |
731 | * user. | |
732 | */ | |
0906e20f | 733 | memset(&addr, 0, sizeof(struct sockaddr_storage)); |
8cec6b80 | 734 | memcpy(&addr, &transport->ipaddr, transport->af_specific->sockaddr_len); |
0906e20f | 735 | event = sctp_ulpevent_make_peer_addr_change(asoc, &addr, |
1da177e4 LT |
736 | 0, spc_state, error, GFP_ATOMIC); |
737 | if (event) | |
738 | sctp_ulpq_tail_event(&asoc->ulpq, event); | |
739 | ||
740 | /* Select new active and retran paths. */ | |
741 | ||
742 | /* Look for the two most recently used active transports. | |
743 | * | |
744 | * This code produces the wrong ordering whenever jiffies | |
745 | * rolls over, but we still get usable transports, so we don't | |
746 | * worry about it. | |
747 | */ | |
748 | first = NULL; second = NULL; | |
749 | ||
750 | list_for_each(pos, &asoc->peer.transport_addr_list) { | |
751 | t = list_entry(pos, struct sctp_transport, transports); | |
752 | ||
ad8fec17 SS |
753 | if ((t->state == SCTP_INACTIVE) || |
754 | (t->state == SCTP_UNCONFIRMED)) | |
1da177e4 LT |
755 | continue; |
756 | if (!first || t->last_time_heard > first->last_time_heard) { | |
757 | second = first; | |
758 | first = t; | |
759 | } | |
760 | if (!second || t->last_time_heard > second->last_time_heard) | |
761 | second = t; | |
762 | } | |
763 | ||
764 | /* RFC 2960 6.4 Multi-Homed SCTP Endpoints | |
765 | * | |
766 | * By default, an endpoint should always transmit to the | |
767 | * primary path, unless the SCTP user explicitly specifies the | |
768 | * destination transport address (and possibly source | |
769 | * transport address) to use. | |
770 | * | |
771 | * [If the primary is active but not most recent, bump the most | |
772 | * recently used transport.] | |
773 | */ | |
ad8fec17 SS |
774 | if (((asoc->peer.primary_path->state == SCTP_ACTIVE) || |
775 | (asoc->peer.primary_path->state == SCTP_UNKNOWN)) && | |
1da177e4 LT |
776 | first != asoc->peer.primary_path) { |
777 | second = first; | |
778 | first = asoc->peer.primary_path; | |
779 | } | |
780 | ||
781 | /* If we failed to find a usable transport, just camp on the | |
782 | * primary, even if it is inactive. | |
783 | */ | |
784 | if (!first) { | |
785 | first = asoc->peer.primary_path; | |
786 | second = asoc->peer.primary_path; | |
787 | } | |
788 | ||
789 | /* Set the active and retran transports. */ | |
790 | asoc->peer.active_path = first; | |
791 | asoc->peer.retran_path = second; | |
792 | } | |
793 | ||
794 | /* Hold a reference to an association. */ | |
795 | void sctp_association_hold(struct sctp_association *asoc) | |
796 | { | |
797 | atomic_inc(&asoc->base.refcnt); | |
798 | } | |
799 | ||
800 | /* Release a reference to an association and cleanup | |
801 | * if there are no more references. | |
802 | */ | |
803 | void sctp_association_put(struct sctp_association *asoc) | |
804 | { | |
805 | if (atomic_dec_and_test(&asoc->base.refcnt)) | |
806 | sctp_association_destroy(asoc); | |
807 | } | |
808 | ||
809 | /* Allocate the next TSN, Transmission Sequence Number, for the given | |
810 | * association. | |
811 | */ | |
812 | __u32 sctp_association_get_next_tsn(struct sctp_association *asoc) | |
813 | { | |
814 | /* From Section 1.6 Serial Number Arithmetic: | |
815 | * Transmission Sequence Numbers wrap around when they reach | |
816 | * 2**32 - 1. That is, the next TSN a DATA chunk MUST use | |
817 | * after transmitting TSN = 2*32 - 1 is TSN = 0. | |
818 | */ | |
819 | __u32 retval = asoc->next_tsn; | |
820 | asoc->next_tsn++; | |
821 | asoc->unack_data++; | |
822 | ||
823 | return retval; | |
824 | } | |
825 | ||
826 | /* Compare two addresses to see if they match. Wildcard addresses | |
827 | * only match themselves. | |
828 | */ | |
829 | int sctp_cmp_addr_exact(const union sctp_addr *ss1, | |
830 | const union sctp_addr *ss2) | |
831 | { | |
832 | struct sctp_af *af; | |
833 | ||
834 | af = sctp_get_af_specific(ss1->sa.sa_family); | |
835 | if (unlikely(!af)) | |
836 | return 0; | |
837 | ||
838 | return af->cmp_addr(ss1, ss2); | |
839 | } | |
840 | ||
841 | /* Return an ecne chunk to get prepended to a packet. | |
842 | * Note: We are sly and return a shared, prealloced chunk. FIXME: | |
843 | * No we don't, but we could/should. | |
844 | */ | |
845 | struct sctp_chunk *sctp_get_ecne_prepend(struct sctp_association *asoc) | |
846 | { | |
847 | struct sctp_chunk *chunk; | |
848 | ||
849 | /* Send ECNE if needed. | |
850 | * Not being able to allocate a chunk here is not deadly. | |
851 | */ | |
852 | if (asoc->need_ecne) | |
853 | chunk = sctp_make_ecne(asoc, asoc->last_ecne_tsn); | |
854 | else | |
855 | chunk = NULL; | |
856 | ||
857 | return chunk; | |
858 | } | |
859 | ||
860 | /* | |
861 | * Find which transport this TSN was sent on. | |
862 | */ | |
863 | struct sctp_transport *sctp_assoc_lookup_tsn(struct sctp_association *asoc, | |
864 | __u32 tsn) | |
865 | { | |
866 | struct sctp_transport *active; | |
867 | struct sctp_transport *match; | |
868 | struct list_head *entry, *pos; | |
869 | struct sctp_transport *transport; | |
870 | struct sctp_chunk *chunk; | |
dbc16db1 | 871 | __be32 key = htonl(tsn); |
1da177e4 LT |
872 | |
873 | match = NULL; | |
874 | ||
875 | /* | |
876 | * FIXME: In general, find a more efficient data structure for | |
877 | * searching. | |
878 | */ | |
879 | ||
880 | /* | |
881 | * The general strategy is to search each transport's transmitted | |
882 | * list. Return which transport this TSN lives on. | |
883 | * | |
884 | * Let's be hopeful and check the active_path first. | |
885 | * Another optimization would be to know if there is only one | |
886 | * outbound path and not have to look for the TSN at all. | |
887 | * | |
888 | */ | |
889 | ||
890 | active = asoc->peer.active_path; | |
891 | ||
892 | list_for_each(entry, &active->transmitted) { | |
893 | chunk = list_entry(entry, struct sctp_chunk, transmitted_list); | |
894 | ||
895 | if (key == chunk->subh.data_hdr->tsn) { | |
896 | match = active; | |
897 | goto out; | |
898 | } | |
899 | } | |
900 | ||
901 | /* If not found, go search all the other transports. */ | |
902 | list_for_each(pos, &asoc->peer.transport_addr_list) { | |
903 | transport = list_entry(pos, struct sctp_transport, transports); | |
904 | ||
905 | if (transport == active) | |
906 | break; | |
907 | list_for_each(entry, &transport->transmitted) { | |
908 | chunk = list_entry(entry, struct sctp_chunk, | |
909 | transmitted_list); | |
910 | if (key == chunk->subh.data_hdr->tsn) { | |
911 | match = transport; | |
912 | goto out; | |
913 | } | |
914 | } | |
915 | } | |
916 | out: | |
917 | return match; | |
918 | } | |
919 | ||
920 | /* Is this the association we are looking for? */ | |
921 | struct sctp_transport *sctp_assoc_is_match(struct sctp_association *asoc, | |
922 | const union sctp_addr *laddr, | |
923 | const union sctp_addr *paddr) | |
924 | { | |
925 | struct sctp_transport *transport; | |
926 | ||
927 | sctp_read_lock(&asoc->base.addr_lock); | |
928 | ||
e2fccedb AV |
929 | if ((htons(asoc->base.bind_addr.port) == laddr->v4.sin_port) && |
930 | (htons(asoc->peer.port) == paddr->v4.sin_port)) { | |
1da177e4 LT |
931 | transport = sctp_assoc_lookup_paddr(asoc, paddr); |
932 | if (!transport) | |
933 | goto out; | |
934 | ||
935 | if (sctp_bind_addr_match(&asoc->base.bind_addr, laddr, | |
936 | sctp_sk(asoc->base.sk))) | |
937 | goto out; | |
938 | } | |
939 | transport = NULL; | |
940 | ||
941 | out: | |
942 | sctp_read_unlock(&asoc->base.addr_lock); | |
943 | return transport; | |
944 | } | |
945 | ||
946 | /* Do delayed input processing. This is scheduled by sctp_rcv(). */ | |
c4028958 | 947 | static void sctp_assoc_bh_rcv(struct work_struct *work) |
1da177e4 | 948 | { |
c4028958 DH |
949 | struct sctp_association *asoc = |
950 | container_of(work, struct sctp_association, | |
951 | base.inqueue.immediate); | |
1da177e4 LT |
952 | struct sctp_endpoint *ep; |
953 | struct sctp_chunk *chunk; | |
954 | struct sock *sk; | |
955 | struct sctp_inq *inqueue; | |
956 | int state; | |
957 | sctp_subtype_t subtype; | |
958 | int error = 0; | |
959 | ||
960 | /* The association should be held so we should be safe. */ | |
961 | ep = asoc->ep; | |
962 | sk = asoc->base.sk; | |
963 | ||
964 | inqueue = &asoc->base.inqueue; | |
965 | sctp_association_hold(asoc); | |
966 | while (NULL != (chunk = sctp_inq_pop(inqueue))) { | |
967 | state = asoc->state; | |
968 | subtype = SCTP_ST_CHUNK(chunk->chunk_hdr->type); | |
969 | ||
970 | /* Remember where the last DATA chunk came from so we | |
971 | * know where to send the SACK. | |
972 | */ | |
973 | if (sctp_chunk_is_data(chunk)) | |
974 | asoc->peer.last_data_from = chunk->transport; | |
975 | else | |
976 | SCTP_INC_STATS(SCTP_MIB_INCTRLCHUNKS); | |
977 | ||
978 | if (chunk->transport) | |
979 | chunk->transport->last_time_heard = jiffies; | |
980 | ||
981 | /* Run through the state machine. */ | |
982 | error = sctp_do_sm(SCTP_EVENT_T_CHUNK, subtype, | |
983 | state, ep, asoc, chunk, GFP_ATOMIC); | |
984 | ||
985 | /* Check to see if the association is freed in response to | |
986 | * the incoming chunk. If so, get out of the while loop. | |
987 | */ | |
988 | if (asoc->base.dead) | |
989 | break; | |
990 | ||
991 | /* If there is an error on chunk, discard this packet. */ | |
992 | if (error && chunk) | |
993 | chunk->pdiscard = 1; | |
994 | } | |
995 | sctp_association_put(asoc); | |
996 | } | |
997 | ||
998 | /* This routine moves an association from its old sk to a new sk. */ | |
999 | void sctp_assoc_migrate(struct sctp_association *assoc, struct sock *newsk) | |
1000 | { | |
1001 | struct sctp_sock *newsp = sctp_sk(newsk); | |
1002 | struct sock *oldsk = assoc->base.sk; | |
1003 | ||
1004 | /* Delete the association from the old endpoint's list of | |
1005 | * associations. | |
1006 | */ | |
1007 | list_del_init(&assoc->asocs); | |
1008 | ||
1009 | /* Decrement the backlog value for a TCP-style socket. */ | |
1010 | if (sctp_style(oldsk, TCP)) | |
1011 | oldsk->sk_ack_backlog--; | |
1012 | ||
1013 | /* Release references to the old endpoint and the sock. */ | |
1014 | sctp_endpoint_put(assoc->ep); | |
1015 | sock_put(assoc->base.sk); | |
1016 | ||
1017 | /* Get a reference to the new endpoint. */ | |
1018 | assoc->ep = newsp->ep; | |
1019 | sctp_endpoint_hold(assoc->ep); | |
1020 | ||
1021 | /* Get a reference to the new sock. */ | |
1022 | assoc->base.sk = newsk; | |
1023 | sock_hold(assoc->base.sk); | |
1024 | ||
1025 | /* Add the association to the new endpoint's list of associations. */ | |
1026 | sctp_endpoint_add_asoc(newsp->ep, assoc); | |
1027 | } | |
1028 | ||
1029 | /* Update an association (possibly from unexpected COOKIE-ECHO processing). */ | |
1030 | void sctp_assoc_update(struct sctp_association *asoc, | |
1031 | struct sctp_association *new) | |
1032 | { | |
1033 | struct sctp_transport *trans; | |
1034 | struct list_head *pos, *temp; | |
1035 | ||
1036 | /* Copy in new parameters of peer. */ | |
1037 | asoc->c = new->c; | |
1038 | asoc->peer.rwnd = new->peer.rwnd; | |
1039 | asoc->peer.sack_needed = new->peer.sack_needed; | |
1040 | asoc->peer.i = new->peer.i; | |
1041 | sctp_tsnmap_init(&asoc->peer.tsn_map, SCTP_TSN_MAP_SIZE, | |
1042 | asoc->peer.i.initial_tsn); | |
1043 | ||
1044 | /* Remove any peer addresses not present in the new association. */ | |
1045 | list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) { | |
1046 | trans = list_entry(pos, struct sctp_transport, transports); | |
1047 | if (!sctp_assoc_lookup_paddr(new, &trans->ipaddr)) | |
1048 | sctp_assoc_del_peer(asoc, &trans->ipaddr); | |
749bf921 VY |
1049 | |
1050 | if (asoc->state >= SCTP_STATE_ESTABLISHED) | |
1051 | sctp_transport_reset(trans); | |
1da177e4 LT |
1052 | } |
1053 | ||
1054 | /* If the case is A (association restart), use | |
1055 | * initial_tsn as next_tsn. If the case is B, use | |
1056 | * current next_tsn in case data sent to peer | |
1057 | * has been discarded and needs retransmission. | |
1058 | */ | |
1059 | if (asoc->state >= SCTP_STATE_ESTABLISHED) { | |
1060 | asoc->next_tsn = new->next_tsn; | |
1061 | asoc->ctsn_ack_point = new->ctsn_ack_point; | |
1062 | asoc->adv_peer_ack_point = new->adv_peer_ack_point; | |
1063 | ||
1064 | /* Reinitialize SSN for both local streams | |
1065 | * and peer's streams. | |
1066 | */ | |
1067 | sctp_ssnmap_clear(asoc->ssnmap); | |
1068 | ||
0b58a811 VY |
1069 | /* Flush the ULP reassembly and ordered queue. |
1070 | * Any data there will now be stale and will | |
1071 | * cause problems. | |
1072 | */ | |
1073 | sctp_ulpq_flush(&asoc->ulpq); | |
1074 | ||
749bf921 VY |
1075 | /* reset the overall association error count so |
1076 | * that the restarted association doesn't get torn | |
1077 | * down on the next retransmission timer. | |
1078 | */ | |
1079 | asoc->overall_error_count = 0; | |
1080 | ||
1da177e4 LT |
1081 | } else { |
1082 | /* Add any peer addresses from the new association. */ | |
1083 | list_for_each(pos, &new->peer.transport_addr_list) { | |
1084 | trans = list_entry(pos, struct sctp_transport, | |
1085 | transports); | |
1086 | if (!sctp_assoc_lookup_paddr(asoc, &trans->ipaddr)) | |
1087 | sctp_assoc_add_peer(asoc, &trans->ipaddr, | |
ad8fec17 | 1088 | GFP_ATOMIC, trans->state); |
1da177e4 LT |
1089 | } |
1090 | ||
1091 | asoc->ctsn_ack_point = asoc->next_tsn - 1; | |
1092 | asoc->adv_peer_ack_point = asoc->ctsn_ack_point; | |
1093 | if (!asoc->ssnmap) { | |
1094 | /* Move the ssnmap. */ | |
1095 | asoc->ssnmap = new->ssnmap; | |
1096 | new->ssnmap = NULL; | |
1097 | } | |
1098 | } | |
1099 | } | |
1100 | ||
1101 | /* Update the retran path for sending a retransmitted packet. | |
1102 | * Round-robin through the active transports, else round-robin | |
1103 | * through the inactive transports as this is the next best thing | |
1104 | * we can try. | |
1105 | */ | |
1106 | void sctp_assoc_update_retran_path(struct sctp_association *asoc) | |
1107 | { | |
1108 | struct sctp_transport *t, *next; | |
1109 | struct list_head *head = &asoc->peer.transport_addr_list; | |
1110 | struct list_head *pos; | |
1111 | ||
1112 | /* Find the next transport in a round-robin fashion. */ | |
1113 | t = asoc->peer.retran_path; | |
1114 | pos = &t->transports; | |
1115 | next = NULL; | |
1116 | ||
1117 | while (1) { | |
1118 | /* Skip the head. */ | |
1119 | if (pos->next == head) | |
1120 | pos = head->next; | |
1121 | else | |
1122 | pos = pos->next; | |
1123 | ||
1124 | t = list_entry(pos, struct sctp_transport, transports); | |
1125 | ||
1126 | /* Try to find an active transport. */ | |
1127 | ||
ad8fec17 SS |
1128 | if ((t->state == SCTP_ACTIVE) || |
1129 | (t->state == SCTP_UNKNOWN)) { | |
1da177e4 LT |
1130 | break; |
1131 | } else { | |
1132 | /* Keep track of the next transport in case | |
1133 | * we don't find any active transport. | |
1134 | */ | |
1135 | if (!next) | |
1136 | next = t; | |
1137 | } | |
1138 | ||
1139 | /* We have exhausted the list, but didn't find any | |
1140 | * other active transports. If so, use the next | |
1141 | * transport. | |
1142 | */ | |
1143 | if (t == asoc->peer.retran_path) { | |
1144 | t = next; | |
1145 | break; | |
1146 | } | |
1147 | } | |
1148 | ||
1149 | asoc->peer.retran_path = t; | |
3f7a87d2 FF |
1150 | |
1151 | SCTP_DEBUG_PRINTK_IPADDR("sctp_assoc_update_retran_path:association" | |
1152 | " %p addr: ", | |
1153 | " port: %d\n", | |
1154 | asoc, | |
1155 | (&t->ipaddr), | |
b3f5b3b6 | 1156 | ntohs(t->ipaddr.v4.sin_port)); |
3f7a87d2 FF |
1157 | } |
1158 | ||
1159 | /* Choose the transport for sending a INIT packet. */ | |
1160 | struct sctp_transport *sctp_assoc_choose_init_transport( | |
1161 | struct sctp_association *asoc) | |
1162 | { | |
1163 | struct sctp_transport *t; | |
1164 | ||
1165 | /* Use the retran path. If the last INIT was sent over the | |
1166 | * retran path, update the retran path and use it. | |
1167 | */ | |
1168 | if (!asoc->init_last_sent_to) { | |
1169 | t = asoc->peer.active_path; | |
1170 | } else { | |
1171 | if (asoc->init_last_sent_to == asoc->peer.retran_path) | |
1172 | sctp_assoc_update_retran_path(asoc); | |
1173 | t = asoc->peer.retran_path; | |
1174 | } | |
1175 | ||
1176 | SCTP_DEBUG_PRINTK_IPADDR("sctp_assoc_update_retran_path:association" | |
1177 | " %p addr: ", | |
1178 | " port: %d\n", | |
1179 | asoc, | |
1180 | (&t->ipaddr), | |
b3f5b3b6 | 1181 | ntohs(t->ipaddr.v4.sin_port)); |
3f7a87d2 FF |
1182 | |
1183 | return t; | |
1da177e4 LT |
1184 | } |
1185 | ||
1186 | /* Choose the transport for sending a SHUTDOWN packet. */ | |
1187 | struct sctp_transport *sctp_assoc_choose_shutdown_transport( | |
1188 | struct sctp_association *asoc) | |
1189 | { | |
1190 | /* If this is the first time SHUTDOWN is sent, use the active path, | |
1191 | * else use the retran path. If the last SHUTDOWN was sent over the | |
1192 | * retran path, update the retran path and use it. | |
1193 | */ | |
1194 | if (!asoc->shutdown_last_sent_to) | |
1195 | return asoc->peer.active_path; | |
1196 | else { | |
1197 | if (asoc->shutdown_last_sent_to == asoc->peer.retran_path) | |
1198 | sctp_assoc_update_retran_path(asoc); | |
1199 | return asoc->peer.retran_path; | |
1200 | } | |
1201 | ||
1202 | } | |
1203 | ||
1204 | /* Update the association's pmtu and frag_point by going through all the | |
1205 | * transports. This routine is called when a transport's PMTU has changed. | |
1206 | */ | |
1207 | void sctp_assoc_sync_pmtu(struct sctp_association *asoc) | |
1208 | { | |
1209 | struct sctp_transport *t; | |
1210 | struct list_head *pos; | |
1211 | __u32 pmtu = 0; | |
1212 | ||
1213 | if (!asoc) | |
1214 | return; | |
1215 | ||
1216 | /* Get the lowest pmtu of all the transports. */ | |
1217 | list_for_each(pos, &asoc->peer.transport_addr_list) { | |
1218 | t = list_entry(pos, struct sctp_transport, transports); | |
52ccb8e9 FF |
1219 | if (!pmtu || (t->pathmtu < pmtu)) |
1220 | pmtu = t->pathmtu; | |
1da177e4 LT |
1221 | } |
1222 | ||
1223 | if (pmtu) { | |
1224 | struct sctp_sock *sp = sctp_sk(asoc->base.sk); | |
52ccb8e9 | 1225 | asoc->pathmtu = pmtu; |
1da177e4 LT |
1226 | asoc->frag_point = sctp_frag_point(sp, pmtu); |
1227 | } | |
1228 | ||
1229 | SCTP_DEBUG_PRINTK("%s: asoc:%p, pmtu:%d, frag_point:%d\n", | |
52ccb8e9 | 1230 | __FUNCTION__, asoc, asoc->pathmtu, asoc->frag_point); |
1da177e4 LT |
1231 | } |
1232 | ||
1233 | /* Should we send a SACK to update our peer? */ | |
1234 | static inline int sctp_peer_needs_update(struct sctp_association *asoc) | |
1235 | { | |
1236 | switch (asoc->state) { | |
1237 | case SCTP_STATE_ESTABLISHED: | |
1238 | case SCTP_STATE_SHUTDOWN_PENDING: | |
1239 | case SCTP_STATE_SHUTDOWN_RECEIVED: | |
1240 | case SCTP_STATE_SHUTDOWN_SENT: | |
1241 | if ((asoc->rwnd > asoc->a_rwnd) && | |
1242 | ((asoc->rwnd - asoc->a_rwnd) >= | |
52ccb8e9 | 1243 | min_t(__u32, (asoc->base.sk->sk_rcvbuf >> 1), asoc->pathmtu))) |
1da177e4 LT |
1244 | return 1; |
1245 | break; | |
1246 | default: | |
1247 | break; | |
1248 | } | |
1249 | return 0; | |
1250 | } | |
1251 | ||
1252 | /* Increase asoc's rwnd by len and send any window update SACK if needed. */ | |
1253 | void sctp_assoc_rwnd_increase(struct sctp_association *asoc, unsigned len) | |
1254 | { | |
1255 | struct sctp_chunk *sack; | |
1256 | struct timer_list *timer; | |
1257 | ||
1258 | if (asoc->rwnd_over) { | |
1259 | if (asoc->rwnd_over >= len) { | |
1260 | asoc->rwnd_over -= len; | |
1261 | } else { | |
1262 | asoc->rwnd += (len - asoc->rwnd_over); | |
1263 | asoc->rwnd_over = 0; | |
1264 | } | |
1265 | } else { | |
1266 | asoc->rwnd += len; | |
1267 | } | |
1268 | ||
1269 | SCTP_DEBUG_PRINTK("%s: asoc %p rwnd increased by %d to (%u, %u) " | |
1270 | "- %u\n", __FUNCTION__, asoc, len, asoc->rwnd, | |
1271 | asoc->rwnd_over, asoc->a_rwnd); | |
1272 | ||
1273 | /* Send a window update SACK if the rwnd has increased by at least the | |
1274 | * minimum of the association's PMTU and half of the receive buffer. | |
1275 | * The algorithm used is similar to the one described in | |
1276 | * Section 4.2.3.3 of RFC 1122. | |
1277 | */ | |
1278 | if (sctp_peer_needs_update(asoc)) { | |
1279 | asoc->a_rwnd = asoc->rwnd; | |
1280 | SCTP_DEBUG_PRINTK("%s: Sending window update SACK- asoc: %p " | |
1281 | "rwnd: %u a_rwnd: %u\n", __FUNCTION__, | |
1282 | asoc, asoc->rwnd, asoc->a_rwnd); | |
1283 | sack = sctp_make_sack(asoc); | |
1284 | if (!sack) | |
1285 | return; | |
1286 | ||
1287 | asoc->peer.sack_needed = 0; | |
1288 | ||
1289 | sctp_outq_tail(&asoc->outqueue, sack); | |
1290 | ||
1291 | /* Stop the SACK timer. */ | |
1292 | timer = &asoc->timers[SCTP_EVENT_TIMEOUT_SACK]; | |
1293 | if (timer_pending(timer) && del_timer(timer)) | |
1294 | sctp_association_put(asoc); | |
1295 | } | |
1296 | } | |
1297 | ||
1298 | /* Decrease asoc's rwnd by len. */ | |
1299 | void sctp_assoc_rwnd_decrease(struct sctp_association *asoc, unsigned len) | |
1300 | { | |
1301 | SCTP_ASSERT(asoc->rwnd, "rwnd zero", return); | |
1302 | SCTP_ASSERT(!asoc->rwnd_over, "rwnd_over not zero", return); | |
1303 | if (asoc->rwnd >= len) { | |
1304 | asoc->rwnd -= len; | |
1305 | } else { | |
1306 | asoc->rwnd_over = len - asoc->rwnd; | |
1307 | asoc->rwnd = 0; | |
1308 | } | |
1309 | SCTP_DEBUG_PRINTK("%s: asoc %p rwnd decreased by %d to (%u, %u)\n", | |
1310 | __FUNCTION__, asoc, len, asoc->rwnd, | |
1311 | asoc->rwnd_over); | |
1312 | } | |
1313 | ||
1314 | /* Build the bind address list for the association based on info from the | |
1315 | * local endpoint and the remote peer. | |
1316 | */ | |
3182cd84 | 1317 | int sctp_assoc_set_bind_addr_from_ep(struct sctp_association *asoc, |
dd0fc66f | 1318 | gfp_t gfp) |
1da177e4 LT |
1319 | { |
1320 | sctp_scope_t scope; | |
1321 | int flags; | |
1322 | ||
1323 | /* Use scoping rules to determine the subset of addresses from | |
1324 | * the endpoint. | |
1325 | */ | |
1326 | scope = sctp_scope(&asoc->peer.active_path->ipaddr); | |
1327 | flags = (PF_INET6 == asoc->base.sk->sk_family) ? SCTP_ADDR6_ALLOWED : 0; | |
1328 | if (asoc->peer.ipv4_address) | |
1329 | flags |= SCTP_ADDR4_PEERSUPP; | |
1330 | if (asoc->peer.ipv6_address) | |
1331 | flags |= SCTP_ADDR6_PEERSUPP; | |
1332 | ||
1333 | return sctp_bind_addr_copy(&asoc->base.bind_addr, | |
1334 | &asoc->ep->base.bind_addr, | |
1335 | scope, gfp, flags); | |
1336 | } | |
1337 | ||
1338 | /* Build the association's bind address list from the cookie. */ | |
1339 | int sctp_assoc_set_bind_addr_from_cookie(struct sctp_association *asoc, | |
3182cd84 | 1340 | struct sctp_cookie *cookie, |
dd0fc66f | 1341 | gfp_t gfp) |
1da177e4 LT |
1342 | { |
1343 | int var_size2 = ntohs(cookie->peer_init->chunk_hdr.length); | |
1344 | int var_size3 = cookie->raw_addr_list_len; | |
1345 | __u8 *raw = (__u8 *)cookie->peer_init + var_size2; | |
1346 | ||
1347 | return sctp_raw_to_bind_addrs(&asoc->base.bind_addr, raw, var_size3, | |
1348 | asoc->ep->base.bind_addr.port, gfp); | |
1349 | } | |
1350 | ||
d808ad9a YH |
1351 | /* Lookup laddr in the bind address list of an association. */ |
1352 | int sctp_assoc_lookup_laddr(struct sctp_association *asoc, | |
1da177e4 LT |
1353 | const union sctp_addr *laddr) |
1354 | { | |
1355 | int found; | |
1356 | ||
1357 | sctp_read_lock(&asoc->base.addr_lock); | |
1358 | if ((asoc->base.bind_addr.port == ntohs(laddr->v4.sin_port)) && | |
1359 | sctp_bind_addr_match(&asoc->base.bind_addr, laddr, | |
d808ad9a | 1360 | sctp_sk(asoc->base.sk))) { |
1da177e4 LT |
1361 | found = 1; |
1362 | goto out; | |
1363 | } | |
1364 | ||
1365 | found = 0; | |
1366 | out: | |
1367 | sctp_read_unlock(&asoc->base.addr_lock); | |
1368 | return found; | |
1369 | } |