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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; | |
a29a5bd4 VY |
77 | sctp_paramhdr_t *p; |
78 | int err; | |
1da177e4 LT |
79 | |
80 | /* Retrieve the SCTP per socket area. */ | |
81 | sp = sctp_sk((struct sock *)sk); | |
82 | ||
83 | /* Init all variables to a known value. */ | |
84 | memset(asoc, 0, sizeof(struct sctp_association)); | |
85 | ||
86 | /* Discarding const is appropriate here. */ | |
87 | asoc->ep = (struct sctp_endpoint *)ep; | |
88 | sctp_endpoint_hold(asoc->ep); | |
89 | ||
90 | /* Hold the sock. */ | |
91 | asoc->base.sk = (struct sock *)sk; | |
92 | sock_hold(asoc->base.sk); | |
93 | ||
94 | /* Initialize the common base substructure. */ | |
95 | asoc->base.type = SCTP_EP_TYPE_ASSOCIATION; | |
96 | ||
97 | /* Initialize the object handling fields. */ | |
98 | atomic_set(&asoc->base.refcnt, 1); | |
99 | asoc->base.dead = 0; | |
100 | asoc->base.malloced = 0; | |
101 | ||
102 | /* Initialize the bind addr area. */ | |
103 | sctp_bind_addr_init(&asoc->base.bind_addr, ep->base.bind_addr.port); | |
1da177e4 LT |
104 | |
105 | asoc->state = SCTP_STATE_CLOSED; | |
106 | ||
107 | /* Set these values from the socket values, a conversion between | |
108 | * millsecons to seconds/microseconds must also be done. | |
109 | */ | |
110 | asoc->cookie_life.tv_sec = sp->assocparams.sasoc_cookie_life / 1000; | |
111 | asoc->cookie_life.tv_usec = (sp->assocparams.sasoc_cookie_life % 1000) | |
112 | * 1000; | |
1da177e4 LT |
113 | asoc->frag_point = 0; |
114 | ||
115 | /* Set the association max_retrans and RTO values from the | |
116 | * socket values. | |
117 | */ | |
118 | asoc->max_retrans = sp->assocparams.sasoc_asocmaxrxt; | |
119 | asoc->rto_initial = msecs_to_jiffies(sp->rtoinfo.srto_initial); | |
120 | asoc->rto_max = msecs_to_jiffies(sp->rtoinfo.srto_max); | |
121 | asoc->rto_min = msecs_to_jiffies(sp->rtoinfo.srto_min); | |
122 | ||
123 | asoc->overall_error_count = 0; | |
124 | ||
52ccb8e9 FF |
125 | /* Initialize the association's heartbeat interval based on the |
126 | * sock configured value. | |
127 | */ | |
128 | asoc->hbinterval = msecs_to_jiffies(sp->hbinterval); | |
129 | ||
130 | /* Initialize path max retrans value. */ | |
131 | asoc->pathmaxrxt = sp->pathmaxrxt; | |
132 | ||
133 | /* Initialize default path MTU. */ | |
134 | asoc->pathmtu = sp->pathmtu; | |
135 | ||
136 | /* Set association default SACK delay */ | |
137 | asoc->sackdelay = msecs_to_jiffies(sp->sackdelay); | |
138 | ||
139 | /* Set the association default flags controlling | |
140 | * Heartbeat, SACK delay, and Path MTU Discovery. | |
141 | */ | |
142 | asoc->param_flags = sp->param_flags; | |
143 | ||
1da177e4 LT |
144 | /* Initialize the maximum mumber of new data packets that can be sent |
145 | * in a burst. | |
146 | */ | |
70331571 | 147 | asoc->max_burst = sp->max_burst; |
1da177e4 | 148 | |
1e7d3d90 VY |
149 | /* initialize association timers */ |
150 | asoc->timeouts[SCTP_EVENT_TIMEOUT_NONE] = 0; | |
151 | asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_COOKIE] = asoc->rto_initial; | |
152 | asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_INIT] = asoc->rto_initial; | |
153 | asoc->timeouts[SCTP_EVENT_TIMEOUT_T2_SHUTDOWN] = asoc->rto_initial; | |
154 | asoc->timeouts[SCTP_EVENT_TIMEOUT_T3_RTX] = 0; | |
155 | asoc->timeouts[SCTP_EVENT_TIMEOUT_T4_RTO] = 0; | |
156 | ||
157 | /* sctpimpguide Section 2.12.2 | |
158 | * If the 'T5-shutdown-guard' timer is used, it SHOULD be set to the | |
159 | * recommended value of 5 times 'RTO.Max'. | |
160 | */ | |
d808ad9a | 161 | asoc->timeouts[SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD] |
1e7d3d90 VY |
162 | = 5 * asoc->rto_max; |
163 | ||
164 | asoc->timeouts[SCTP_EVENT_TIMEOUT_HEARTBEAT] = 0; | |
52ccb8e9 | 165 | asoc->timeouts[SCTP_EVENT_TIMEOUT_SACK] = asoc->sackdelay; |
1e7d3d90 VY |
166 | asoc->timeouts[SCTP_EVENT_TIMEOUT_AUTOCLOSE] = |
167 | sp->autoclose * HZ; | |
d808ad9a | 168 | |
1e7d3d90 | 169 | /* Initilizes the timers */ |
b24b8a24 PE |
170 | for (i = SCTP_EVENT_TIMEOUT_NONE; i < SCTP_NUM_TIMEOUT_TYPES; ++i) |
171 | setup_timer(&asoc->timers[i], sctp_timer_events[i], | |
172 | (unsigned long)asoc); | |
1da177e4 LT |
173 | |
174 | /* Pull default initialization values from the sock options. | |
175 | * Note: This assumes that the values have already been | |
176 | * validated in the sock. | |
177 | */ | |
178 | asoc->c.sinit_max_instreams = sp->initmsg.sinit_max_instreams; | |
179 | asoc->c.sinit_num_ostreams = sp->initmsg.sinit_num_ostreams; | |
180 | asoc->max_init_attempts = sp->initmsg.sinit_max_attempts; | |
181 | ||
182 | asoc->max_init_timeo = | |
183 | msecs_to_jiffies(sp->initmsg.sinit_max_init_timeo); | |
184 | ||
185 | /* Allocate storage for the ssnmap after the inbound and outbound | |
186 | * streams have been negotiated during Init. | |
187 | */ | |
188 | asoc->ssnmap = NULL; | |
189 | ||
190 | /* Set the local window size for receive. | |
191 | * This is also the rcvbuf space per association. | |
192 | * RFC 6 - A SCTP receiver MUST be able to receive a minimum of | |
193 | * 1500 bytes in one SCTP packet. | |
194 | */ | |
049b3ff5 | 195 | if ((sk->sk_rcvbuf/2) < SCTP_DEFAULT_MINWINDOW) |
1da177e4 LT |
196 | asoc->rwnd = SCTP_DEFAULT_MINWINDOW; |
197 | else | |
049b3ff5 | 198 | asoc->rwnd = sk->sk_rcvbuf/2; |
1da177e4 LT |
199 | |
200 | asoc->a_rwnd = asoc->rwnd; | |
201 | ||
202 | asoc->rwnd_over = 0; | |
203 | ||
204 | /* Use my own max window until I learn something better. */ | |
205 | asoc->peer.rwnd = SCTP_DEFAULT_MAXWINDOW; | |
206 | ||
207 | /* Set the sndbuf size for transmit. */ | |
208 | asoc->sndbuf_used = 0; | |
209 | ||
049b3ff5 NH |
210 | /* Initialize the receive memory counter */ |
211 | atomic_set(&asoc->rmem_alloc, 0); | |
212 | ||
1da177e4 LT |
213 | init_waitqueue_head(&asoc->wait); |
214 | ||
215 | asoc->c.my_vtag = sctp_generate_tag(ep); | |
216 | asoc->peer.i.init_tag = 0; /* INIT needs a vtag of 0. */ | |
217 | asoc->c.peer_vtag = 0; | |
218 | asoc->c.my_ttag = 0; | |
219 | asoc->c.peer_ttag = 0; | |
220 | asoc->c.my_port = ep->base.bind_addr.port; | |
221 | ||
222 | asoc->c.initial_tsn = sctp_generate_tsn(ep); | |
223 | ||
224 | asoc->next_tsn = asoc->c.initial_tsn; | |
225 | ||
226 | asoc->ctsn_ack_point = asoc->next_tsn - 1; | |
227 | asoc->adv_peer_ack_point = asoc->ctsn_ack_point; | |
228 | asoc->highest_sacked = asoc->ctsn_ack_point; | |
229 | asoc->last_cwr_tsn = asoc->ctsn_ack_point; | |
230 | asoc->unack_data = 0; | |
231 | ||
1da177e4 LT |
232 | /* ADDIP Section 4.1 Asconf Chunk Procedures |
233 | * | |
234 | * When an endpoint has an ASCONF signaled change to be sent to the | |
235 | * remote endpoint it should do the following: | |
236 | * ... | |
237 | * A2) a serial number should be assigned to the chunk. The serial | |
238 | * number SHOULD be a monotonically increasing number. The serial | |
239 | * numbers SHOULD be initialized at the start of the | |
240 | * association to the same value as the initial TSN. | |
241 | */ | |
242 | asoc->addip_serial = asoc->c.initial_tsn; | |
243 | ||
79af02c2 | 244 | INIT_LIST_HEAD(&asoc->addip_chunk_list); |
1da177e4 LT |
245 | |
246 | /* Make an empty list of remote transport addresses. */ | |
247 | INIT_LIST_HEAD(&asoc->peer.transport_addr_list); | |
3f7a87d2 | 248 | asoc->peer.transport_count = 0; |
1da177e4 LT |
249 | |
250 | /* RFC 2960 5.1 Normal Establishment of an Association | |
251 | * | |
252 | * After the reception of the first data chunk in an | |
253 | * association the endpoint must immediately respond with a | |
254 | * sack to acknowledge the data chunk. Subsequent | |
255 | * acknowledgements should be done as described in Section | |
256 | * 6.2. | |
257 | * | |
258 | * [We implement this by telling a new association that it | |
259 | * already received one packet.] | |
260 | */ | |
261 | asoc->peer.sack_needed = 1; | |
262 | ||
73d9c4fd VY |
263 | /* Assume that the peer will tell us if he recognizes ASCONF |
264 | * as part of INIT exchange. | |
265 | * The sctp_addip_noauth option is there for backward compatibilty | |
266 | * and will revert old behavior. | |
1da177e4 | 267 | */ |
88799fe5 | 268 | asoc->peer.asconf_capable = 0; |
73d9c4fd VY |
269 | if (sctp_addip_noauth) |
270 | asoc->peer.asconf_capable = 1; | |
1da177e4 LT |
271 | |
272 | /* Create an input queue. */ | |
273 | sctp_inq_init(&asoc->base.inqueue); | |
c4028958 | 274 | sctp_inq_set_th_handler(&asoc->base.inqueue, sctp_assoc_bh_rcv); |
1da177e4 LT |
275 | |
276 | /* Create an output queue. */ | |
277 | sctp_outq_init(asoc, &asoc->outqueue); | |
278 | ||
279 | if (!sctp_ulpq_init(&asoc->ulpq, asoc)) | |
280 | goto fail_init; | |
281 | ||
282 | /* Set up the tsn tracking. */ | |
283 | sctp_tsnmap_init(&asoc->peer.tsn_map, SCTP_TSN_MAP_SIZE, 0); | |
284 | ||
285 | asoc->need_ecne = 0; | |
286 | ||
287 | asoc->assoc_id = 0; | |
288 | ||
289 | /* Assume that peer would support both address types unless we are | |
290 | * told otherwise. | |
291 | */ | |
292 | asoc->peer.ipv4_address = 1; | |
293 | asoc->peer.ipv6_address = 1; | |
294 | INIT_LIST_HEAD(&asoc->asocs); | |
295 | ||
296 | asoc->autoclose = sp->autoclose; | |
297 | ||
298 | asoc->default_stream = sp->default_stream; | |
299 | asoc->default_ppid = sp->default_ppid; | |
300 | asoc->default_flags = sp->default_flags; | |
301 | asoc->default_context = sp->default_context; | |
302 | asoc->default_timetolive = sp->default_timetolive; | |
6ab792f5 | 303 | asoc->default_rcv_context = sp->default_rcv_context; |
1da177e4 | 304 | |
a29a5bd4 VY |
305 | /* AUTH related initializations */ |
306 | INIT_LIST_HEAD(&asoc->endpoint_shared_keys); | |
307 | err = sctp_auth_asoc_copy_shkeys(ep, asoc, gfp); | |
308 | if (err) | |
309 | goto fail_init; | |
310 | ||
311 | asoc->active_key_id = ep->active_key_id; | |
312 | asoc->asoc_shared_key = NULL; | |
313 | ||
314 | asoc->default_hmac_id = 0; | |
315 | /* Save the hmacs and chunks list into this association */ | |
316 | if (ep->auth_hmacs_list) | |
317 | memcpy(asoc->c.auth_hmacs, ep->auth_hmacs_list, | |
318 | ntohs(ep->auth_hmacs_list->param_hdr.length)); | |
319 | if (ep->auth_chunk_list) | |
320 | memcpy(asoc->c.auth_chunks, ep->auth_chunk_list, | |
321 | ntohs(ep->auth_chunk_list->param_hdr.length)); | |
322 | ||
323 | /* Get the AUTH random number for this association */ | |
324 | p = (sctp_paramhdr_t *)asoc->c.auth_random; | |
325 | p->type = SCTP_PARAM_RANDOM; | |
326 | p->length = htons(sizeof(sctp_paramhdr_t) + SCTP_AUTH_RANDOM_LENGTH); | |
327 | get_random_bytes(p+1, SCTP_AUTH_RANDOM_LENGTH); | |
328 | ||
1da177e4 LT |
329 | return asoc; |
330 | ||
331 | fail_init: | |
332 | sctp_endpoint_put(asoc->ep); | |
333 | sock_put(asoc->base.sk); | |
334 | return NULL; | |
335 | } | |
336 | ||
337 | /* Allocate and initialize a new association */ | |
338 | struct sctp_association *sctp_association_new(const struct sctp_endpoint *ep, | |
339 | const struct sock *sk, | |
3182cd84 | 340 | sctp_scope_t scope, |
dd0fc66f | 341 | gfp_t gfp) |
1da177e4 LT |
342 | { |
343 | struct sctp_association *asoc; | |
344 | ||
345 | asoc = t_new(struct sctp_association, gfp); | |
346 | if (!asoc) | |
347 | goto fail; | |
348 | ||
349 | if (!sctp_association_init(asoc, ep, sk, scope, gfp)) | |
350 | goto fail_init; | |
351 | ||
352 | asoc->base.malloced = 1; | |
353 | SCTP_DBG_OBJCNT_INC(assoc); | |
3f7a87d2 | 354 | SCTP_DEBUG_PRINTK("Created asoc %p\n", asoc); |
1da177e4 LT |
355 | |
356 | return asoc; | |
357 | ||
358 | fail_init: | |
359 | kfree(asoc); | |
360 | fail: | |
361 | return NULL; | |
362 | } | |
363 | ||
364 | /* Free this association if possible. There may still be users, so | |
365 | * the actual deallocation may be delayed. | |
366 | */ | |
367 | void sctp_association_free(struct sctp_association *asoc) | |
368 | { | |
369 | struct sock *sk = asoc->base.sk; | |
370 | struct sctp_transport *transport; | |
371 | struct list_head *pos, *temp; | |
372 | int i; | |
373 | ||
de76e695 VY |
374 | /* Only real associations count against the endpoint, so |
375 | * don't bother for if this is a temporary association. | |
376 | */ | |
377 | if (!asoc->temp) { | |
378 | list_del(&asoc->asocs); | |
379 | ||
380 | /* Decrement the backlog value for a TCP-style listening | |
381 | * socket. | |
382 | */ | |
383 | if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING)) | |
384 | sk->sk_ack_backlog--; | |
385 | } | |
1da177e4 LT |
386 | |
387 | /* Mark as dead, so other users can know this structure is | |
388 | * going away. | |
389 | */ | |
390 | asoc->base.dead = 1; | |
391 | ||
392 | /* Dispose of any data lying around in the outqueue. */ | |
393 | sctp_outq_free(&asoc->outqueue); | |
394 | ||
395 | /* Dispose of any pending messages for the upper layer. */ | |
396 | sctp_ulpq_free(&asoc->ulpq); | |
397 | ||
398 | /* Dispose of any pending chunks on the inqueue. */ | |
399 | sctp_inq_free(&asoc->base.inqueue); | |
400 | ||
401 | /* Free ssnmap storage. */ | |
402 | sctp_ssnmap_free(asoc->ssnmap); | |
403 | ||
404 | /* Clean up the bound address list. */ | |
405 | sctp_bind_addr_free(&asoc->base.bind_addr); | |
406 | ||
407 | /* Do we need to go through all of our timers and | |
408 | * delete them? To be safe we will try to delete all, but we | |
409 | * should be able to go through and make a guess based | |
410 | * on our state. | |
411 | */ | |
412 | for (i = SCTP_EVENT_TIMEOUT_NONE; i < SCTP_NUM_TIMEOUT_TYPES; ++i) { | |
413 | if (timer_pending(&asoc->timers[i]) && | |
414 | del_timer(&asoc->timers[i])) | |
415 | sctp_association_put(asoc); | |
416 | } | |
417 | ||
418 | /* Free peer's cached cookie. */ | |
a51482bd | 419 | kfree(asoc->peer.cookie); |
730fc3d0 VY |
420 | kfree(asoc->peer.peer_random); |
421 | kfree(asoc->peer.peer_chunks); | |
422 | kfree(asoc->peer.peer_hmacs); | |
1da177e4 LT |
423 | |
424 | /* Release the transport structures. */ | |
425 | list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) { | |
426 | transport = list_entry(pos, struct sctp_transport, transports); | |
427 | list_del(pos); | |
428 | sctp_transport_free(transport); | |
429 | } | |
430 | ||
3f7a87d2 FF |
431 | asoc->peer.transport_count = 0; |
432 | ||
1da177e4 LT |
433 | /* Free any cached ASCONF_ACK chunk. */ |
434 | if (asoc->addip_last_asconf_ack) | |
435 | sctp_chunk_free(asoc->addip_last_asconf_ack); | |
436 | ||
437 | /* Free any cached ASCONF chunk. */ | |
438 | if (asoc->addip_last_asconf) | |
439 | sctp_chunk_free(asoc->addip_last_asconf); | |
440 | ||
a29a5bd4 VY |
441 | /* AUTH - Free the endpoint shared keys */ |
442 | sctp_auth_destroy_keys(&asoc->endpoint_shared_keys); | |
443 | ||
444 | /* AUTH - Free the association shared key */ | |
445 | sctp_auth_key_put(asoc->asoc_shared_key); | |
446 | ||
1da177e4 LT |
447 | sctp_association_put(asoc); |
448 | } | |
449 | ||
450 | /* Cleanup and free up an association. */ | |
451 | static void sctp_association_destroy(struct sctp_association *asoc) | |
452 | { | |
453 | SCTP_ASSERT(asoc->base.dead, "Assoc is not dead", return); | |
454 | ||
455 | sctp_endpoint_put(asoc->ep); | |
456 | sock_put(asoc->base.sk); | |
457 | ||
458 | if (asoc->assoc_id != 0) { | |
459 | spin_lock_bh(&sctp_assocs_id_lock); | |
460 | idr_remove(&sctp_assocs_id, asoc->assoc_id); | |
461 | spin_unlock_bh(&sctp_assocs_id_lock); | |
462 | } | |
463 | ||
049b3ff5 NH |
464 | BUG_TRAP(!atomic_read(&asoc->rmem_alloc)); |
465 | ||
1da177e4 LT |
466 | if (asoc->base.malloced) { |
467 | kfree(asoc); | |
468 | SCTP_DBG_OBJCNT_DEC(assoc); | |
469 | } | |
470 | } | |
471 | ||
472 | /* Change the primary destination address for the peer. */ | |
473 | void sctp_assoc_set_primary(struct sctp_association *asoc, | |
474 | struct sctp_transport *transport) | |
475 | { | |
476 | asoc->peer.primary_path = transport; | |
477 | ||
478 | /* Set a default msg_name for events. */ | |
479 | memcpy(&asoc->peer.primary_addr, &transport->ipaddr, | |
480 | sizeof(union sctp_addr)); | |
481 | ||
482 | /* If the primary path is changing, assume that the | |
483 | * user wants to use this new path. | |
484 | */ | |
ad8fec17 SS |
485 | if ((transport->state == SCTP_ACTIVE) || |
486 | (transport->state == SCTP_UNKNOWN)) | |
1da177e4 LT |
487 | asoc->peer.active_path = transport; |
488 | ||
489 | /* | |
490 | * SFR-CACC algorithm: | |
491 | * Upon the receipt of a request to change the primary | |
492 | * destination address, on the data structure for the new | |
493 | * primary destination, the sender MUST do the following: | |
494 | * | |
495 | * 1) If CHANGEOVER_ACTIVE is set, then there was a switch | |
496 | * to this destination address earlier. The sender MUST set | |
497 | * CYCLING_CHANGEOVER to indicate that this switch is a | |
498 | * double switch to the same destination address. | |
499 | */ | |
500 | if (transport->cacc.changeover_active) | |
501 | transport->cacc.cycling_changeover = 1; | |
502 | ||
503 | /* 2) The sender MUST set CHANGEOVER_ACTIVE to indicate that | |
504 | * a changeover has occurred. | |
505 | */ | |
506 | transport->cacc.changeover_active = 1; | |
507 | ||
508 | /* 3) The sender MUST store the next TSN to be sent in | |
509 | * next_tsn_at_change. | |
510 | */ | |
511 | transport->cacc.next_tsn_at_change = asoc->next_tsn; | |
512 | } | |
513 | ||
3f7a87d2 FF |
514 | /* Remove a transport from an association. */ |
515 | void sctp_assoc_rm_peer(struct sctp_association *asoc, | |
516 | struct sctp_transport *peer) | |
517 | { | |
518 | struct list_head *pos; | |
519 | struct sctp_transport *transport; | |
520 | ||
521 | SCTP_DEBUG_PRINTK_IPADDR("sctp_assoc_rm_peer:association %p addr: ", | |
522 | " port: %d\n", | |
523 | asoc, | |
524 | (&peer->ipaddr), | |
b3f5b3b6 | 525 | ntohs(peer->ipaddr.v4.sin_port)); |
3f7a87d2 FF |
526 | |
527 | /* If we are to remove the current retran_path, update it | |
528 | * to the next peer before removing this peer from the list. | |
529 | */ | |
530 | if (asoc->peer.retran_path == peer) | |
531 | sctp_assoc_update_retran_path(asoc); | |
532 | ||
533 | /* Remove this peer from the list. */ | |
534 | list_del(&peer->transports); | |
535 | ||
536 | /* Get the first transport of asoc. */ | |
537 | pos = asoc->peer.transport_addr_list.next; | |
538 | transport = list_entry(pos, struct sctp_transport, transports); | |
539 | ||
540 | /* Update any entries that match the peer to be deleted. */ | |
541 | if (asoc->peer.primary_path == peer) | |
542 | sctp_assoc_set_primary(asoc, transport); | |
543 | if (asoc->peer.active_path == peer) | |
544 | asoc->peer.active_path = transport; | |
545 | if (asoc->peer.last_data_from == peer) | |
546 | asoc->peer.last_data_from = transport; | |
547 | ||
548 | /* If we remove the transport an INIT was last sent to, set it to | |
549 | * NULL. Combined with the update of the retran path above, this | |
550 | * will cause the next INIT to be sent to the next available | |
551 | * transport, maintaining the cycle. | |
552 | */ | |
553 | if (asoc->init_last_sent_to == peer) | |
554 | asoc->init_last_sent_to = NULL; | |
555 | ||
556 | asoc->peer.transport_count--; | |
557 | ||
558 | sctp_transport_free(peer); | |
559 | } | |
560 | ||
1da177e4 LT |
561 | /* Add a transport address to an association. */ |
562 | struct sctp_transport *sctp_assoc_add_peer(struct sctp_association *asoc, | |
563 | const union sctp_addr *addr, | |
dd0fc66f | 564 | const gfp_t gfp, |
3f7a87d2 | 565 | const int peer_state) |
1da177e4 LT |
566 | { |
567 | struct sctp_transport *peer; | |
568 | struct sctp_sock *sp; | |
569 | unsigned short port; | |
570 | ||
571 | sp = sctp_sk(asoc->base.sk); | |
572 | ||
573 | /* AF_INET and AF_INET6 share common port field. */ | |
4bdf4b5f | 574 | port = ntohs(addr->v4.sin_port); |
1da177e4 | 575 | |
3f7a87d2 | 576 | SCTP_DEBUG_PRINTK_IPADDR("sctp_assoc_add_peer:association %p addr: ", |
ad8fec17 | 577 | " port: %d state:%d\n", |
3f7a87d2 FF |
578 | asoc, |
579 | addr, | |
4bdf4b5f | 580 | port, |
ad8fec17 | 581 | peer_state); |
3f7a87d2 | 582 | |
1da177e4 LT |
583 | /* Set the port if it has not been set yet. */ |
584 | if (0 == asoc->peer.port) | |
585 | asoc->peer.port = port; | |
586 | ||
587 | /* Check to see if this is a duplicate. */ | |
588 | peer = sctp_assoc_lookup_paddr(asoc, addr); | |
3f7a87d2 | 589 | if (peer) { |
ad8fec17 SS |
590 | if (peer->state == SCTP_UNKNOWN) { |
591 | if (peer_state == SCTP_ACTIVE) | |
592 | peer->state = SCTP_ACTIVE; | |
593 | if (peer_state == SCTP_UNCONFIRMED) | |
594 | peer->state = SCTP_UNCONFIRMED; | |
595 | } | |
1da177e4 | 596 | return peer; |
3f7a87d2 | 597 | } |
1da177e4 LT |
598 | |
599 | peer = sctp_transport_new(addr, gfp); | |
600 | if (!peer) | |
601 | return NULL; | |
602 | ||
603 | sctp_transport_set_owner(peer, asoc); | |
604 | ||
52ccb8e9 FF |
605 | /* Initialize the peer's heartbeat interval based on the |
606 | * association configured value. | |
607 | */ | |
608 | peer->hbinterval = asoc->hbinterval; | |
609 | ||
610 | /* Set the path max_retrans. */ | |
611 | peer->pathmaxrxt = asoc->pathmaxrxt; | |
612 | ||
613 | /* Initialize the peer's SACK delay timeout based on the | |
614 | * association configured value. | |
615 | */ | |
616 | peer->sackdelay = asoc->sackdelay; | |
617 | ||
618 | /* Enable/disable heartbeat, SACK delay, and path MTU discovery | |
619 | * based on association setting. | |
620 | */ | |
621 | peer->param_flags = asoc->param_flags; | |
622 | ||
1da177e4 | 623 | /* Initialize the pmtu of the transport. */ |
52ccb8e9 FF |
624 | if (peer->param_flags & SPP_PMTUD_ENABLE) |
625 | sctp_transport_pmtu(peer); | |
626 | else if (asoc->pathmtu) | |
627 | peer->pathmtu = asoc->pathmtu; | |
628 | else | |
629 | peer->pathmtu = SCTP_DEFAULT_MAXSEGMENT; | |
1da177e4 LT |
630 | |
631 | /* If this is the first transport addr on this association, | |
632 | * initialize the association PMTU to the peer's PMTU. | |
633 | * If not and the current association PMTU is higher than the new | |
634 | * peer's PMTU, reset the association PMTU to the new peer's PMTU. | |
635 | */ | |
52ccb8e9 FF |
636 | if (asoc->pathmtu) |
637 | asoc->pathmtu = min_t(int, peer->pathmtu, asoc->pathmtu); | |
1da177e4 | 638 | else |
52ccb8e9 | 639 | asoc->pathmtu = peer->pathmtu; |
1da177e4 LT |
640 | |
641 | SCTP_DEBUG_PRINTK("sctp_assoc_add_peer:association %p PMTU set to " | |
52ccb8e9 | 642 | "%d\n", asoc, asoc->pathmtu); |
1da177e4 | 643 | |
52ccb8e9 | 644 | asoc->frag_point = sctp_frag_point(sp, asoc->pathmtu); |
1da177e4 LT |
645 | |
646 | /* The asoc->peer.port might not be meaningful yet, but | |
647 | * initialize the packet structure anyway. | |
648 | */ | |
649 | sctp_packet_init(&peer->packet, peer, asoc->base.bind_addr.port, | |
650 | asoc->peer.port); | |
651 | ||
652 | /* 7.2.1 Slow-Start | |
653 | * | |
654 | * o The initial cwnd before DATA transmission or after a sufficiently | |
655 | * long idle period MUST be set to | |
656 | * min(4*MTU, max(2*MTU, 4380 bytes)) | |
657 | * | |
658 | * o The initial value of ssthresh MAY be arbitrarily high | |
659 | * (for example, implementations MAY use the size of the | |
660 | * receiver advertised window). | |
661 | */ | |
52ccb8e9 | 662 | peer->cwnd = min(4*asoc->pathmtu, max_t(__u32, 2*asoc->pathmtu, 4380)); |
1da177e4 LT |
663 | |
664 | /* At this point, we may not have the receiver's advertised window, | |
665 | * so initialize ssthresh to the default value and it will be set | |
666 | * later when we process the INIT. | |
667 | */ | |
668 | peer->ssthresh = SCTP_DEFAULT_MAXWINDOW; | |
669 | ||
670 | peer->partial_bytes_acked = 0; | |
671 | peer->flight_size = 0; | |
672 | ||
1da177e4 LT |
673 | /* Set the transport's RTO.initial value */ |
674 | peer->rto = asoc->rto_initial; | |
675 | ||
3f7a87d2 FF |
676 | /* Set the peer's active state. */ |
677 | peer->state = peer_state; | |
678 | ||
1da177e4 LT |
679 | /* Attach the remote transport to our asoc. */ |
680 | list_add_tail(&peer->transports, &asoc->peer.transport_addr_list); | |
3f7a87d2 | 681 | asoc->peer.transport_count++; |
1da177e4 LT |
682 | |
683 | /* If we do not yet have a primary path, set one. */ | |
684 | if (!asoc->peer.primary_path) { | |
685 | sctp_assoc_set_primary(asoc, peer); | |
686 | asoc->peer.retran_path = peer; | |
687 | } | |
688 | ||
3f7a87d2 | 689 | if (asoc->peer.active_path == asoc->peer.retran_path) { |
1da177e4 | 690 | asoc->peer.retran_path = peer; |
3f7a87d2 | 691 | } |
1da177e4 LT |
692 | |
693 | return peer; | |
694 | } | |
695 | ||
696 | /* Delete a transport address from an association. */ | |
697 | void sctp_assoc_del_peer(struct sctp_association *asoc, | |
698 | const union sctp_addr *addr) | |
699 | { | |
700 | struct list_head *pos; | |
701 | struct list_head *temp; | |
1da177e4 LT |
702 | struct sctp_transport *transport; |
703 | ||
704 | list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) { | |
705 | transport = list_entry(pos, struct sctp_transport, transports); | |
706 | if (sctp_cmp_addr_exact(addr, &transport->ipaddr)) { | |
3f7a87d2 FF |
707 | /* Do book keeping for removing the peer and free it. */ |
708 | sctp_assoc_rm_peer(asoc, transport); | |
1da177e4 LT |
709 | break; |
710 | } | |
711 | } | |
1da177e4 LT |
712 | } |
713 | ||
714 | /* Lookup a transport by address. */ | |
715 | struct sctp_transport *sctp_assoc_lookup_paddr( | |
716 | const struct sctp_association *asoc, | |
717 | const union sctp_addr *address) | |
718 | { | |
719 | struct sctp_transport *t; | |
720 | struct list_head *pos; | |
721 | ||
722 | /* Cycle through all transports searching for a peer address. */ | |
723 | ||
724 | list_for_each(pos, &asoc->peer.transport_addr_list) { | |
725 | t = list_entry(pos, struct sctp_transport, transports); | |
726 | if (sctp_cmp_addr_exact(address, &t->ipaddr)) | |
727 | return t; | |
728 | } | |
729 | ||
730 | return NULL; | |
731 | } | |
732 | ||
733 | /* Engage in transport control operations. | |
734 | * Mark the transport up or down and send a notification to the user. | |
735 | * Select and update the new active and retran paths. | |
736 | */ | |
737 | void sctp_assoc_control_transport(struct sctp_association *asoc, | |
738 | struct sctp_transport *transport, | |
739 | sctp_transport_cmd_t command, | |
740 | sctp_sn_error_t error) | |
741 | { | |
742 | struct sctp_transport *t = NULL; | |
743 | struct sctp_transport *first; | |
744 | struct sctp_transport *second; | |
745 | struct sctp_ulpevent *event; | |
0906e20f | 746 | struct sockaddr_storage addr; |
1da177e4 LT |
747 | struct list_head *pos; |
748 | int spc_state = 0; | |
749 | ||
750 | /* Record the transition on the transport. */ | |
751 | switch (command) { | |
752 | case SCTP_TRANSPORT_UP: | |
1ae4114d VY |
753 | /* If we are moving from UNCONFIRMED state due |
754 | * to heartbeat success, report the SCTP_ADDR_CONFIRMED | |
755 | * state to the user, otherwise report SCTP_ADDR_AVAILABLE. | |
756 | */ | |
757 | if (SCTP_UNCONFIRMED == transport->state && | |
758 | SCTP_HEARTBEAT_SUCCESS == error) | |
759 | spc_state = SCTP_ADDR_CONFIRMED; | |
760 | else | |
761 | spc_state = SCTP_ADDR_AVAILABLE; | |
3f7a87d2 | 762 | transport->state = SCTP_ACTIVE; |
1da177e4 LT |
763 | break; |
764 | ||
765 | case SCTP_TRANSPORT_DOWN: | |
cc75689a VY |
766 | /* if the transort was never confirmed, do not transition it |
767 | * to inactive state. | |
768 | */ | |
769 | if (transport->state != SCTP_UNCONFIRMED) | |
770 | transport->state = SCTP_INACTIVE; | |
771 | ||
1da177e4 LT |
772 | spc_state = SCTP_ADDR_UNREACHABLE; |
773 | break; | |
774 | ||
775 | default: | |
776 | return; | |
3ff50b79 | 777 | } |
1da177e4 LT |
778 | |
779 | /* Generate and send a SCTP_PEER_ADDR_CHANGE notification to the | |
780 | * user. | |
781 | */ | |
0906e20f | 782 | memset(&addr, 0, sizeof(struct sockaddr_storage)); |
8cec6b80 | 783 | memcpy(&addr, &transport->ipaddr, transport->af_specific->sockaddr_len); |
0906e20f | 784 | event = sctp_ulpevent_make_peer_addr_change(asoc, &addr, |
1da177e4 LT |
785 | 0, spc_state, error, GFP_ATOMIC); |
786 | if (event) | |
787 | sctp_ulpq_tail_event(&asoc->ulpq, event); | |
788 | ||
789 | /* Select new active and retran paths. */ | |
790 | ||
791 | /* Look for the two most recently used active transports. | |
792 | * | |
793 | * This code produces the wrong ordering whenever jiffies | |
794 | * rolls over, but we still get usable transports, so we don't | |
795 | * worry about it. | |
796 | */ | |
797 | first = NULL; second = NULL; | |
798 | ||
799 | list_for_each(pos, &asoc->peer.transport_addr_list) { | |
800 | t = list_entry(pos, struct sctp_transport, transports); | |
801 | ||
ad8fec17 SS |
802 | if ((t->state == SCTP_INACTIVE) || |
803 | (t->state == SCTP_UNCONFIRMED)) | |
1da177e4 LT |
804 | continue; |
805 | if (!first || t->last_time_heard > first->last_time_heard) { | |
806 | second = first; | |
807 | first = t; | |
808 | } | |
809 | if (!second || t->last_time_heard > second->last_time_heard) | |
810 | second = t; | |
811 | } | |
812 | ||
813 | /* RFC 2960 6.4 Multi-Homed SCTP Endpoints | |
814 | * | |
815 | * By default, an endpoint should always transmit to the | |
816 | * primary path, unless the SCTP user explicitly specifies the | |
817 | * destination transport address (and possibly source | |
818 | * transport address) to use. | |
819 | * | |
820 | * [If the primary is active but not most recent, bump the most | |
821 | * recently used transport.] | |
822 | */ | |
ad8fec17 SS |
823 | if (((asoc->peer.primary_path->state == SCTP_ACTIVE) || |
824 | (asoc->peer.primary_path->state == SCTP_UNKNOWN)) && | |
1da177e4 LT |
825 | first != asoc->peer.primary_path) { |
826 | second = first; | |
827 | first = asoc->peer.primary_path; | |
828 | } | |
829 | ||
830 | /* If we failed to find a usable transport, just camp on the | |
831 | * primary, even if it is inactive. | |
832 | */ | |
833 | if (!first) { | |
834 | first = asoc->peer.primary_path; | |
835 | second = asoc->peer.primary_path; | |
836 | } | |
837 | ||
838 | /* Set the active and retran transports. */ | |
839 | asoc->peer.active_path = first; | |
840 | asoc->peer.retran_path = second; | |
841 | } | |
842 | ||
843 | /* Hold a reference to an association. */ | |
844 | void sctp_association_hold(struct sctp_association *asoc) | |
845 | { | |
846 | atomic_inc(&asoc->base.refcnt); | |
847 | } | |
848 | ||
849 | /* Release a reference to an association and cleanup | |
850 | * if there are no more references. | |
851 | */ | |
852 | void sctp_association_put(struct sctp_association *asoc) | |
853 | { | |
854 | if (atomic_dec_and_test(&asoc->base.refcnt)) | |
855 | sctp_association_destroy(asoc); | |
856 | } | |
857 | ||
858 | /* Allocate the next TSN, Transmission Sequence Number, for the given | |
859 | * association. | |
860 | */ | |
861 | __u32 sctp_association_get_next_tsn(struct sctp_association *asoc) | |
862 | { | |
863 | /* From Section 1.6 Serial Number Arithmetic: | |
864 | * Transmission Sequence Numbers wrap around when they reach | |
865 | * 2**32 - 1. That is, the next TSN a DATA chunk MUST use | |
866 | * after transmitting TSN = 2*32 - 1 is TSN = 0. | |
867 | */ | |
868 | __u32 retval = asoc->next_tsn; | |
869 | asoc->next_tsn++; | |
870 | asoc->unack_data++; | |
871 | ||
872 | return retval; | |
873 | } | |
874 | ||
875 | /* Compare two addresses to see if they match. Wildcard addresses | |
876 | * only match themselves. | |
877 | */ | |
878 | int sctp_cmp_addr_exact(const union sctp_addr *ss1, | |
879 | const union sctp_addr *ss2) | |
880 | { | |
881 | struct sctp_af *af; | |
882 | ||
883 | af = sctp_get_af_specific(ss1->sa.sa_family); | |
884 | if (unlikely(!af)) | |
885 | return 0; | |
886 | ||
887 | return af->cmp_addr(ss1, ss2); | |
888 | } | |
889 | ||
890 | /* Return an ecne chunk to get prepended to a packet. | |
891 | * Note: We are sly and return a shared, prealloced chunk. FIXME: | |
892 | * No we don't, but we could/should. | |
893 | */ | |
894 | struct sctp_chunk *sctp_get_ecne_prepend(struct sctp_association *asoc) | |
895 | { | |
896 | struct sctp_chunk *chunk; | |
897 | ||
898 | /* Send ECNE if needed. | |
899 | * Not being able to allocate a chunk here is not deadly. | |
900 | */ | |
901 | if (asoc->need_ecne) | |
902 | chunk = sctp_make_ecne(asoc, asoc->last_ecne_tsn); | |
903 | else | |
904 | chunk = NULL; | |
905 | ||
906 | return chunk; | |
907 | } | |
908 | ||
909 | /* | |
910 | * Find which transport this TSN was sent on. | |
911 | */ | |
912 | struct sctp_transport *sctp_assoc_lookup_tsn(struct sctp_association *asoc, | |
913 | __u32 tsn) | |
914 | { | |
915 | struct sctp_transport *active; | |
916 | struct sctp_transport *match; | |
917 | struct list_head *entry, *pos; | |
918 | struct sctp_transport *transport; | |
919 | struct sctp_chunk *chunk; | |
dbc16db1 | 920 | __be32 key = htonl(tsn); |
1da177e4 LT |
921 | |
922 | match = NULL; | |
923 | ||
924 | /* | |
925 | * FIXME: In general, find a more efficient data structure for | |
926 | * searching. | |
927 | */ | |
928 | ||
929 | /* | |
930 | * The general strategy is to search each transport's transmitted | |
931 | * list. Return which transport this TSN lives on. | |
932 | * | |
933 | * Let's be hopeful and check the active_path first. | |
934 | * Another optimization would be to know if there is only one | |
935 | * outbound path and not have to look for the TSN at all. | |
936 | * | |
937 | */ | |
938 | ||
939 | active = asoc->peer.active_path; | |
940 | ||
941 | list_for_each(entry, &active->transmitted) { | |
942 | chunk = list_entry(entry, struct sctp_chunk, transmitted_list); | |
943 | ||
944 | if (key == chunk->subh.data_hdr->tsn) { | |
945 | match = active; | |
946 | goto out; | |
947 | } | |
948 | } | |
949 | ||
950 | /* If not found, go search all the other transports. */ | |
951 | list_for_each(pos, &asoc->peer.transport_addr_list) { | |
952 | transport = list_entry(pos, struct sctp_transport, transports); | |
953 | ||
954 | if (transport == active) | |
955 | break; | |
956 | list_for_each(entry, &transport->transmitted) { | |
957 | chunk = list_entry(entry, struct sctp_chunk, | |
958 | transmitted_list); | |
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, | |
971 | const union sctp_addr *laddr, | |
972 | const union sctp_addr *paddr) | |
973 | { | |
974 | struct sctp_transport *transport; | |
975 | ||
e2fccedb AV |
976 | if ((htons(asoc->base.bind_addr.port) == laddr->v4.sin_port) && |
977 | (htons(asoc->peer.port) == paddr->v4.sin_port)) { | |
1da177e4 LT |
978 | transport = sctp_assoc_lookup_paddr(asoc, paddr); |
979 | if (!transport) | |
980 | goto out; | |
981 | ||
982 | if (sctp_bind_addr_match(&asoc->base.bind_addr, laddr, | |
983 | sctp_sk(asoc->base.sk))) | |
984 | goto out; | |
985 | } | |
986 | transport = NULL; | |
987 | ||
988 | out: | |
1da177e4 LT |
989 | return transport; |
990 | } | |
991 | ||
992 | /* Do delayed input processing. This is scheduled by sctp_rcv(). */ | |
c4028958 | 993 | static void sctp_assoc_bh_rcv(struct work_struct *work) |
1da177e4 | 994 | { |
c4028958 DH |
995 | struct sctp_association *asoc = |
996 | container_of(work, struct sctp_association, | |
997 | base.inqueue.immediate); | |
1da177e4 LT |
998 | struct sctp_endpoint *ep; |
999 | struct sctp_chunk *chunk; | |
1000 | struct sock *sk; | |
1001 | struct sctp_inq *inqueue; | |
1002 | int state; | |
1003 | sctp_subtype_t subtype; | |
1004 | int error = 0; | |
1005 | ||
1006 | /* The association should be held so we should be safe. */ | |
1007 | ep = asoc->ep; | |
1008 | sk = asoc->base.sk; | |
1009 | ||
1010 | inqueue = &asoc->base.inqueue; | |
1011 | sctp_association_hold(asoc); | |
1012 | while (NULL != (chunk = sctp_inq_pop(inqueue))) { | |
1013 | state = asoc->state; | |
1014 | subtype = SCTP_ST_CHUNK(chunk->chunk_hdr->type); | |
1015 | ||
bbd0d598 VY |
1016 | /* SCTP-AUTH, Section 6.3: |
1017 | * The receiver has a list of chunk types which it expects | |
1018 | * to be received only after an AUTH-chunk. This list has | |
1019 | * been sent to the peer during the association setup. It | |
1020 | * MUST silently discard these chunks if they are not placed | |
1021 | * after an AUTH chunk in the packet. | |
1022 | */ | |
1023 | if (sctp_auth_recv_cid(subtype.chunk, asoc) && !chunk->auth) | |
1024 | continue; | |
1025 | ||
1da177e4 LT |
1026 | /* Remember where the last DATA chunk came from so we |
1027 | * know where to send the SACK. | |
1028 | */ | |
1029 | if (sctp_chunk_is_data(chunk)) | |
1030 | asoc->peer.last_data_from = chunk->transport; | |
1031 | else | |
1032 | SCTP_INC_STATS(SCTP_MIB_INCTRLCHUNKS); | |
1033 | ||
1034 | if (chunk->transport) | |
1035 | chunk->transport->last_time_heard = jiffies; | |
1036 | ||
1037 | /* Run through the state machine. */ | |
1038 | error = sctp_do_sm(SCTP_EVENT_T_CHUNK, subtype, | |
1039 | state, ep, asoc, chunk, GFP_ATOMIC); | |
1040 | ||
1041 | /* Check to see if the association is freed in response to | |
1042 | * the incoming chunk. If so, get out of the while loop. | |
1043 | */ | |
1044 | if (asoc->base.dead) | |
1045 | break; | |
1046 | ||
1047 | /* If there is an error on chunk, discard this packet. */ | |
1048 | if (error && chunk) | |
1049 | chunk->pdiscard = 1; | |
1050 | } | |
1051 | sctp_association_put(asoc); | |
1052 | } | |
1053 | ||
1054 | /* This routine moves an association from its old sk to a new sk. */ | |
1055 | void sctp_assoc_migrate(struct sctp_association *assoc, struct sock *newsk) | |
1056 | { | |
1057 | struct sctp_sock *newsp = sctp_sk(newsk); | |
1058 | struct sock *oldsk = assoc->base.sk; | |
1059 | ||
1060 | /* Delete the association from the old endpoint's list of | |
1061 | * associations. | |
1062 | */ | |
1063 | list_del_init(&assoc->asocs); | |
1064 | ||
1065 | /* Decrement the backlog value for a TCP-style socket. */ | |
1066 | if (sctp_style(oldsk, TCP)) | |
1067 | oldsk->sk_ack_backlog--; | |
1068 | ||
1069 | /* Release references to the old endpoint and the sock. */ | |
1070 | sctp_endpoint_put(assoc->ep); | |
1071 | sock_put(assoc->base.sk); | |
1072 | ||
1073 | /* Get a reference to the new endpoint. */ | |
1074 | assoc->ep = newsp->ep; | |
1075 | sctp_endpoint_hold(assoc->ep); | |
1076 | ||
1077 | /* Get a reference to the new sock. */ | |
1078 | assoc->base.sk = newsk; | |
1079 | sock_hold(assoc->base.sk); | |
1080 | ||
1081 | /* Add the association to the new endpoint's list of associations. */ | |
1082 | sctp_endpoint_add_asoc(newsp->ep, assoc); | |
1083 | } | |
1084 | ||
1085 | /* Update an association (possibly from unexpected COOKIE-ECHO processing). */ | |
1086 | void sctp_assoc_update(struct sctp_association *asoc, | |
1087 | struct sctp_association *new) | |
1088 | { | |
1089 | struct sctp_transport *trans; | |
1090 | struct list_head *pos, *temp; | |
1091 | ||
1092 | /* Copy in new parameters of peer. */ | |
1093 | asoc->c = new->c; | |
1094 | asoc->peer.rwnd = new->peer.rwnd; | |
1095 | asoc->peer.sack_needed = new->peer.sack_needed; | |
1096 | asoc->peer.i = new->peer.i; | |
1097 | sctp_tsnmap_init(&asoc->peer.tsn_map, SCTP_TSN_MAP_SIZE, | |
1098 | asoc->peer.i.initial_tsn); | |
1099 | ||
1100 | /* Remove any peer addresses not present in the new association. */ | |
1101 | list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) { | |
1102 | trans = list_entry(pos, struct sctp_transport, transports); | |
1103 | if (!sctp_assoc_lookup_paddr(new, &trans->ipaddr)) | |
1104 | sctp_assoc_del_peer(asoc, &trans->ipaddr); | |
749bf921 VY |
1105 | |
1106 | if (asoc->state >= SCTP_STATE_ESTABLISHED) | |
1107 | sctp_transport_reset(trans); | |
1da177e4 LT |
1108 | } |
1109 | ||
1110 | /* If the case is A (association restart), use | |
1111 | * initial_tsn as next_tsn. If the case is B, use | |
1112 | * current next_tsn in case data sent to peer | |
1113 | * has been discarded and needs retransmission. | |
1114 | */ | |
1115 | if (asoc->state >= SCTP_STATE_ESTABLISHED) { | |
1116 | asoc->next_tsn = new->next_tsn; | |
1117 | asoc->ctsn_ack_point = new->ctsn_ack_point; | |
1118 | asoc->adv_peer_ack_point = new->adv_peer_ack_point; | |
1119 | ||
1120 | /* Reinitialize SSN for both local streams | |
1121 | * and peer's streams. | |
1122 | */ | |
1123 | sctp_ssnmap_clear(asoc->ssnmap); | |
1124 | ||
0b58a811 VY |
1125 | /* Flush the ULP reassembly and ordered queue. |
1126 | * Any data there will now be stale and will | |
1127 | * cause problems. | |
1128 | */ | |
1129 | sctp_ulpq_flush(&asoc->ulpq); | |
1130 | ||
749bf921 VY |
1131 | /* reset the overall association error count so |
1132 | * that the restarted association doesn't get torn | |
1133 | * down on the next retransmission timer. | |
1134 | */ | |
1135 | asoc->overall_error_count = 0; | |
1136 | ||
1da177e4 LT |
1137 | } else { |
1138 | /* Add any peer addresses from the new association. */ | |
1139 | list_for_each(pos, &new->peer.transport_addr_list) { | |
1140 | trans = list_entry(pos, struct sctp_transport, | |
1141 | transports); | |
1142 | if (!sctp_assoc_lookup_paddr(asoc, &trans->ipaddr)) | |
1143 | sctp_assoc_add_peer(asoc, &trans->ipaddr, | |
ad8fec17 | 1144 | GFP_ATOMIC, trans->state); |
1da177e4 LT |
1145 | } |
1146 | ||
1147 | asoc->ctsn_ack_point = asoc->next_tsn - 1; | |
1148 | asoc->adv_peer_ack_point = asoc->ctsn_ack_point; | |
1149 | if (!asoc->ssnmap) { | |
1150 | /* Move the ssnmap. */ | |
1151 | asoc->ssnmap = new->ssnmap; | |
1152 | new->ssnmap = NULL; | |
1153 | } | |
07d93967 VY |
1154 | |
1155 | if (!asoc->assoc_id) { | |
1156 | /* get a new association id since we don't have one | |
1157 | * yet. | |
1158 | */ | |
1159 | sctp_assoc_set_id(asoc, GFP_ATOMIC); | |
1160 | } | |
1da177e4 | 1161 | } |
a29a5bd4 | 1162 | |
730fc3d0 VY |
1163 | /* SCTP-AUTH: Save the peer parameters from the new assocaitions |
1164 | * and also move the association shared keys over | |
1165 | */ | |
1166 | kfree(asoc->peer.peer_random); | |
1167 | asoc->peer.peer_random = new->peer.peer_random; | |
1168 | new->peer.peer_random = NULL; | |
1169 | ||
1170 | kfree(asoc->peer.peer_chunks); | |
1171 | asoc->peer.peer_chunks = new->peer.peer_chunks; | |
1172 | new->peer.peer_chunks = NULL; | |
1173 | ||
1174 | kfree(asoc->peer.peer_hmacs); | |
1175 | asoc->peer.peer_hmacs = new->peer.peer_hmacs; | |
1176 | new->peer.peer_hmacs = NULL; | |
1177 | ||
1178 | sctp_auth_key_put(asoc->asoc_shared_key); | |
1179 | sctp_auth_asoc_init_active_key(asoc, GFP_ATOMIC); | |
1da177e4 LT |
1180 | } |
1181 | ||
1182 | /* Update the retran path for sending a retransmitted packet. | |
1183 | * Round-robin through the active transports, else round-robin | |
1184 | * through the inactive transports as this is the next best thing | |
1185 | * we can try. | |
1186 | */ | |
1187 | void sctp_assoc_update_retran_path(struct sctp_association *asoc) | |
1188 | { | |
1189 | struct sctp_transport *t, *next; | |
1190 | struct list_head *head = &asoc->peer.transport_addr_list; | |
1191 | struct list_head *pos; | |
1192 | ||
1193 | /* Find the next transport in a round-robin fashion. */ | |
1194 | t = asoc->peer.retran_path; | |
1195 | pos = &t->transports; | |
1196 | next = NULL; | |
1197 | ||
1198 | while (1) { | |
1199 | /* Skip the head. */ | |
1200 | if (pos->next == head) | |
1201 | pos = head->next; | |
1202 | else | |
1203 | pos = pos->next; | |
1204 | ||
1205 | t = list_entry(pos, struct sctp_transport, transports); | |
1206 | ||
1207 | /* Try to find an active transport. */ | |
1208 | ||
ad8fec17 SS |
1209 | if ((t->state == SCTP_ACTIVE) || |
1210 | (t->state == SCTP_UNKNOWN)) { | |
1da177e4 LT |
1211 | break; |
1212 | } else { | |
1213 | /* Keep track of the next transport in case | |
1214 | * we don't find any active transport. | |
1215 | */ | |
1216 | if (!next) | |
1217 | next = t; | |
1218 | } | |
1219 | ||
1220 | /* We have exhausted the list, but didn't find any | |
1221 | * other active transports. If so, use the next | |
1222 | * transport. | |
1223 | */ | |
1224 | if (t == asoc->peer.retran_path) { | |
1225 | t = next; | |
1226 | break; | |
1227 | } | |
1228 | } | |
1229 | ||
1230 | asoc->peer.retran_path = t; | |
3f7a87d2 FF |
1231 | |
1232 | SCTP_DEBUG_PRINTK_IPADDR("sctp_assoc_update_retran_path:association" | |
1233 | " %p addr: ", | |
1234 | " port: %d\n", | |
1235 | asoc, | |
1236 | (&t->ipaddr), | |
b3f5b3b6 | 1237 | ntohs(t->ipaddr.v4.sin_port)); |
3f7a87d2 FF |
1238 | } |
1239 | ||
1240 | /* Choose the transport for sending a INIT packet. */ | |
1241 | struct sctp_transport *sctp_assoc_choose_init_transport( | |
1242 | struct sctp_association *asoc) | |
1243 | { | |
1244 | struct sctp_transport *t; | |
1245 | ||
1246 | /* Use the retran path. If the last INIT was sent over the | |
1247 | * retran path, update the retran path and use it. | |
1248 | */ | |
1249 | if (!asoc->init_last_sent_to) { | |
1250 | t = asoc->peer.active_path; | |
1251 | } else { | |
1252 | if (asoc->init_last_sent_to == asoc->peer.retran_path) | |
1253 | sctp_assoc_update_retran_path(asoc); | |
1254 | t = asoc->peer.retran_path; | |
1255 | } | |
1256 | ||
1257 | SCTP_DEBUG_PRINTK_IPADDR("sctp_assoc_update_retran_path:association" | |
1258 | " %p addr: ", | |
1259 | " port: %d\n", | |
1260 | asoc, | |
1261 | (&t->ipaddr), | |
b3f5b3b6 | 1262 | ntohs(t->ipaddr.v4.sin_port)); |
3f7a87d2 FF |
1263 | |
1264 | return t; | |
1da177e4 LT |
1265 | } |
1266 | ||
1267 | /* Choose the transport for sending a SHUTDOWN packet. */ | |
1268 | struct sctp_transport *sctp_assoc_choose_shutdown_transport( | |
1269 | struct sctp_association *asoc) | |
1270 | { | |
1271 | /* If this is the first time SHUTDOWN is sent, use the active path, | |
1272 | * else use the retran path. If the last SHUTDOWN was sent over the | |
1273 | * retran path, update the retran path and use it. | |
1274 | */ | |
1275 | if (!asoc->shutdown_last_sent_to) | |
1276 | return asoc->peer.active_path; | |
1277 | else { | |
1278 | if (asoc->shutdown_last_sent_to == asoc->peer.retran_path) | |
1279 | sctp_assoc_update_retran_path(asoc); | |
1280 | return asoc->peer.retran_path; | |
1281 | } | |
1282 | ||
1283 | } | |
1284 | ||
1285 | /* Update the association's pmtu and frag_point by going through all the | |
1286 | * transports. This routine is called when a transport's PMTU has changed. | |
1287 | */ | |
1288 | void sctp_assoc_sync_pmtu(struct sctp_association *asoc) | |
1289 | { | |
1290 | struct sctp_transport *t; | |
1291 | struct list_head *pos; | |
1292 | __u32 pmtu = 0; | |
1293 | ||
1294 | if (!asoc) | |
1295 | return; | |
1296 | ||
1297 | /* Get the lowest pmtu of all the transports. */ | |
1298 | list_for_each(pos, &asoc->peer.transport_addr_list) { | |
1299 | t = list_entry(pos, struct sctp_transport, transports); | |
8a479491 VY |
1300 | if (t->pmtu_pending && t->dst) { |
1301 | sctp_transport_update_pmtu(t, dst_mtu(t->dst)); | |
1302 | t->pmtu_pending = 0; | |
1303 | } | |
52ccb8e9 FF |
1304 | if (!pmtu || (t->pathmtu < pmtu)) |
1305 | pmtu = t->pathmtu; | |
1da177e4 LT |
1306 | } |
1307 | ||
1308 | if (pmtu) { | |
1309 | struct sctp_sock *sp = sctp_sk(asoc->base.sk); | |
52ccb8e9 | 1310 | asoc->pathmtu = pmtu; |
1da177e4 LT |
1311 | asoc->frag_point = sctp_frag_point(sp, pmtu); |
1312 | } | |
1313 | ||
1314 | SCTP_DEBUG_PRINTK("%s: asoc:%p, pmtu:%d, frag_point:%d\n", | |
52ccb8e9 | 1315 | __FUNCTION__, asoc, asoc->pathmtu, asoc->frag_point); |
1da177e4 LT |
1316 | } |
1317 | ||
1318 | /* Should we send a SACK to update our peer? */ | |
1319 | static inline int sctp_peer_needs_update(struct sctp_association *asoc) | |
1320 | { | |
1321 | switch (asoc->state) { | |
1322 | case SCTP_STATE_ESTABLISHED: | |
1323 | case SCTP_STATE_SHUTDOWN_PENDING: | |
1324 | case SCTP_STATE_SHUTDOWN_RECEIVED: | |
1325 | case SCTP_STATE_SHUTDOWN_SENT: | |
1326 | if ((asoc->rwnd > asoc->a_rwnd) && | |
1327 | ((asoc->rwnd - asoc->a_rwnd) >= | |
52ccb8e9 | 1328 | min_t(__u32, (asoc->base.sk->sk_rcvbuf >> 1), asoc->pathmtu))) |
1da177e4 LT |
1329 | return 1; |
1330 | break; | |
1331 | default: | |
1332 | break; | |
1333 | } | |
1334 | return 0; | |
1335 | } | |
1336 | ||
1337 | /* Increase asoc's rwnd by len and send any window update SACK if needed. */ | |
1338 | void sctp_assoc_rwnd_increase(struct sctp_association *asoc, unsigned len) | |
1339 | { | |
1340 | struct sctp_chunk *sack; | |
1341 | struct timer_list *timer; | |
1342 | ||
1343 | if (asoc->rwnd_over) { | |
1344 | if (asoc->rwnd_over >= len) { | |
1345 | asoc->rwnd_over -= len; | |
1346 | } else { | |
1347 | asoc->rwnd += (len - asoc->rwnd_over); | |
1348 | asoc->rwnd_over = 0; | |
1349 | } | |
1350 | } else { | |
1351 | asoc->rwnd += len; | |
1352 | } | |
1353 | ||
1354 | SCTP_DEBUG_PRINTK("%s: asoc %p rwnd increased by %d to (%u, %u) " | |
1355 | "- %u\n", __FUNCTION__, asoc, len, asoc->rwnd, | |
1356 | asoc->rwnd_over, asoc->a_rwnd); | |
1357 | ||
1358 | /* Send a window update SACK if the rwnd has increased by at least the | |
1359 | * minimum of the association's PMTU and half of the receive buffer. | |
1360 | * The algorithm used is similar to the one described in | |
1361 | * Section 4.2.3.3 of RFC 1122. | |
1362 | */ | |
1363 | if (sctp_peer_needs_update(asoc)) { | |
1364 | asoc->a_rwnd = asoc->rwnd; | |
1365 | SCTP_DEBUG_PRINTK("%s: Sending window update SACK- asoc: %p " | |
1366 | "rwnd: %u a_rwnd: %u\n", __FUNCTION__, | |
1367 | asoc, asoc->rwnd, asoc->a_rwnd); | |
1368 | sack = sctp_make_sack(asoc); | |
1369 | if (!sack) | |
1370 | return; | |
1371 | ||
1372 | asoc->peer.sack_needed = 0; | |
1373 | ||
1374 | sctp_outq_tail(&asoc->outqueue, sack); | |
1375 | ||
1376 | /* Stop the SACK timer. */ | |
1377 | timer = &asoc->timers[SCTP_EVENT_TIMEOUT_SACK]; | |
1378 | if (timer_pending(timer) && del_timer(timer)) | |
1379 | sctp_association_put(asoc); | |
1380 | } | |
1381 | } | |
1382 | ||
1383 | /* Decrease asoc's rwnd by len. */ | |
1384 | void sctp_assoc_rwnd_decrease(struct sctp_association *asoc, unsigned len) | |
1385 | { | |
1386 | SCTP_ASSERT(asoc->rwnd, "rwnd zero", return); | |
1387 | SCTP_ASSERT(!asoc->rwnd_over, "rwnd_over not zero", return); | |
1388 | if (asoc->rwnd >= len) { | |
1389 | asoc->rwnd -= len; | |
1390 | } else { | |
1391 | asoc->rwnd_over = len - asoc->rwnd; | |
1392 | asoc->rwnd = 0; | |
1393 | } | |
1394 | SCTP_DEBUG_PRINTK("%s: asoc %p rwnd decreased by %d to (%u, %u)\n", | |
1395 | __FUNCTION__, asoc, len, asoc->rwnd, | |
1396 | asoc->rwnd_over); | |
1397 | } | |
1398 | ||
1399 | /* Build the bind address list for the association based on info from the | |
1400 | * local endpoint and the remote peer. | |
1401 | */ | |
3182cd84 | 1402 | int sctp_assoc_set_bind_addr_from_ep(struct sctp_association *asoc, |
dd0fc66f | 1403 | gfp_t gfp) |
1da177e4 LT |
1404 | { |
1405 | sctp_scope_t scope; | |
1406 | int flags; | |
1407 | ||
1408 | /* Use scoping rules to determine the subset of addresses from | |
1409 | * the endpoint. | |
1410 | */ | |
1411 | scope = sctp_scope(&asoc->peer.active_path->ipaddr); | |
1412 | flags = (PF_INET6 == asoc->base.sk->sk_family) ? SCTP_ADDR6_ALLOWED : 0; | |
1413 | if (asoc->peer.ipv4_address) | |
1414 | flags |= SCTP_ADDR4_PEERSUPP; | |
1415 | if (asoc->peer.ipv6_address) | |
1416 | flags |= SCTP_ADDR6_PEERSUPP; | |
1417 | ||
1418 | return sctp_bind_addr_copy(&asoc->base.bind_addr, | |
1419 | &asoc->ep->base.bind_addr, | |
1420 | scope, gfp, flags); | |
1421 | } | |
1422 | ||
1423 | /* Build the association's bind address list from the cookie. */ | |
1424 | int sctp_assoc_set_bind_addr_from_cookie(struct sctp_association *asoc, | |
3182cd84 | 1425 | struct sctp_cookie *cookie, |
dd0fc66f | 1426 | gfp_t gfp) |
1da177e4 LT |
1427 | { |
1428 | int var_size2 = ntohs(cookie->peer_init->chunk_hdr.length); | |
1429 | int var_size3 = cookie->raw_addr_list_len; | |
1430 | __u8 *raw = (__u8 *)cookie->peer_init + var_size2; | |
1431 | ||
1432 | return sctp_raw_to_bind_addrs(&asoc->base.bind_addr, raw, var_size3, | |
1433 | asoc->ep->base.bind_addr.port, gfp); | |
1434 | } | |
1435 | ||
d808ad9a YH |
1436 | /* Lookup laddr in the bind address list of an association. */ |
1437 | int sctp_assoc_lookup_laddr(struct sctp_association *asoc, | |
1da177e4 LT |
1438 | const union sctp_addr *laddr) |
1439 | { | |
559cf710 | 1440 | int found = 0; |
1da177e4 | 1441 | |
1da177e4 LT |
1442 | if ((asoc->base.bind_addr.port == ntohs(laddr->v4.sin_port)) && |
1443 | sctp_bind_addr_match(&asoc->base.bind_addr, laddr, | |
559cf710 | 1444 | sctp_sk(asoc->base.sk))) |
1da177e4 | 1445 | found = 1; |
1da177e4 | 1446 | |
1da177e4 LT |
1447 | return found; |
1448 | } | |
07d93967 VY |
1449 | |
1450 | /* Set an association id for a given association */ | |
1451 | int sctp_assoc_set_id(struct sctp_association *asoc, gfp_t gfp) | |
1452 | { | |
1453 | int assoc_id; | |
1454 | int error = 0; | |
1455 | retry: | |
1456 | if (unlikely(!idr_pre_get(&sctp_assocs_id, gfp))) | |
1457 | return -ENOMEM; | |
1458 | ||
1459 | spin_lock_bh(&sctp_assocs_id_lock); | |
1460 | error = idr_get_new_above(&sctp_assocs_id, (void *)asoc, | |
1461 | 1, &assoc_id); | |
1462 | spin_unlock_bh(&sctp_assocs_id_lock); | |
1463 | if (error == -EAGAIN) | |
1464 | goto retry; | |
1465 | else if (error) | |
1466 | return error; | |
1467 | ||
1468 | asoc->assoc_id = (sctp_assoc_t) assoc_id; | |
1469 | return error; | |
1470 | } |