Commit | Line | Data |
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60c778b2 | 1 | /* SCTP kernel implementation |
1da177e4 LT |
2 | * (C) Copyright IBM Corp. 2001, 2004 |
3 | * Copyright (c) 1999-2000 Cisco, Inc. | |
4 | * Copyright (c) 1999-2001 Motorola, Inc. | |
5 | * Copyright (c) 2001 Intel Corp. | |
6 | * Copyright (c) 2001 La Monte H.P. Yarroll | |
7 | * | |
60c778b2 | 8 | * This file is part of the SCTP kernel implementation |
1da177e4 LT |
9 | * |
10 | * This module provides the abstraction for an SCTP association. | |
11 | * | |
60c778b2 | 12 | * This SCTP implementation is free software; |
1da177e4 LT |
13 | * you can redistribute it and/or modify it under the terms of |
14 | * the GNU General Public License as published by | |
15 | * the Free Software Foundation; either version 2, or (at your option) | |
16 | * any later version. | |
17 | * | |
60c778b2 | 18 | * This SCTP implementation is distributed in the hope that it |
1da177e4 LT |
19 | * will be useful, but WITHOUT ANY WARRANTY; without even the implied |
20 | * ************************ | |
21 | * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. | |
22 | * See the GNU General Public License for more details. | |
23 | * | |
24 | * You should have received a copy of the GNU General Public License | |
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); |
a08de64d | 64 | static void sctp_assoc_free_asconf_acks(struct sctp_association *asoc); |
1da177e4 LT |
65 | |
66 | ||
67 | /* 1st Level Abstractions. */ | |
68 | ||
69 | /* Initialize a new association from provided memory. */ | |
70 | static struct sctp_association *sctp_association_init(struct sctp_association *asoc, | |
71 | const struct sctp_endpoint *ep, | |
72 | const struct sock *sk, | |
73 | sctp_scope_t scope, | |
dd0fc66f | 74 | gfp_t gfp) |
1da177e4 LT |
75 | { |
76 | struct sctp_sock *sp; | |
77 | int i; | |
a29a5bd4 VY |
78 | sctp_paramhdr_t *p; |
79 | int err; | |
1da177e4 LT |
80 | |
81 | /* Retrieve the SCTP per socket area. */ | |
82 | sp = sctp_sk((struct sock *)sk); | |
83 | ||
84 | /* Init all variables to a known value. */ | |
85 | memset(asoc, 0, sizeof(struct sctp_association)); | |
86 | ||
87 | /* Discarding const is appropriate here. */ | |
88 | asoc->ep = (struct sctp_endpoint *)ep; | |
89 | sctp_endpoint_hold(asoc->ep); | |
90 | ||
91 | /* Hold the sock. */ | |
92 | asoc->base.sk = (struct sock *)sk; | |
93 | sock_hold(asoc->base.sk); | |
94 | ||
95 | /* Initialize the common base substructure. */ | |
96 | asoc->base.type = SCTP_EP_TYPE_ASSOCIATION; | |
97 | ||
98 | /* Initialize the object handling fields. */ | |
99 | atomic_set(&asoc->base.refcnt, 1); | |
100 | asoc->base.dead = 0; | |
101 | asoc->base.malloced = 0; | |
102 | ||
103 | /* Initialize the bind addr area. */ | |
104 | sctp_bind_addr_init(&asoc->base.bind_addr, ep->base.bind_addr.port); | |
1da177e4 LT |
105 | |
106 | asoc->state = SCTP_STATE_CLOSED; | |
107 | ||
108 | /* Set these values from the socket values, a conversion between | |
109 | * millsecons to seconds/microseconds must also be done. | |
110 | */ | |
111 | asoc->cookie_life.tv_sec = sp->assocparams.sasoc_cookie_life / 1000; | |
112 | asoc->cookie_life.tv_usec = (sp->assocparams.sasoc_cookie_life % 1000) | |
113 | * 1000; | |
1da177e4 LT |
114 | asoc->frag_point = 0; |
115 | ||
116 | /* Set the association max_retrans and RTO values from the | |
117 | * socket values. | |
118 | */ | |
119 | asoc->max_retrans = sp->assocparams.sasoc_asocmaxrxt; | |
120 | asoc->rto_initial = msecs_to_jiffies(sp->rtoinfo.srto_initial); | |
121 | asoc->rto_max = msecs_to_jiffies(sp->rtoinfo.srto_max); | |
122 | asoc->rto_min = msecs_to_jiffies(sp->rtoinfo.srto_min); | |
123 | ||
124 | asoc->overall_error_count = 0; | |
125 | ||
52ccb8e9 FF |
126 | /* Initialize the association's heartbeat interval based on the |
127 | * sock configured value. | |
128 | */ | |
129 | asoc->hbinterval = msecs_to_jiffies(sp->hbinterval); | |
130 | ||
131 | /* Initialize path max retrans value. */ | |
132 | asoc->pathmaxrxt = sp->pathmaxrxt; | |
133 | ||
134 | /* Initialize default path MTU. */ | |
135 | asoc->pathmtu = sp->pathmtu; | |
136 | ||
137 | /* Set association default SACK delay */ | |
138 | asoc->sackdelay = msecs_to_jiffies(sp->sackdelay); | |
139 | ||
140 | /* Set the association default flags controlling | |
141 | * Heartbeat, SACK delay, and Path MTU Discovery. | |
142 | */ | |
143 | asoc->param_flags = sp->param_flags; | |
144 | ||
1da177e4 LT |
145 | /* Initialize the maximum mumber of new data packets that can be sent |
146 | * in a burst. | |
147 | */ | |
70331571 | 148 | asoc->max_burst = sp->max_burst; |
1da177e4 | 149 | |
1e7d3d90 VY |
150 | /* initialize association timers */ |
151 | asoc->timeouts[SCTP_EVENT_TIMEOUT_NONE] = 0; | |
152 | asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_COOKIE] = asoc->rto_initial; | |
153 | asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_INIT] = asoc->rto_initial; | |
154 | asoc->timeouts[SCTP_EVENT_TIMEOUT_T2_SHUTDOWN] = asoc->rto_initial; | |
155 | asoc->timeouts[SCTP_EVENT_TIMEOUT_T3_RTX] = 0; | |
156 | asoc->timeouts[SCTP_EVENT_TIMEOUT_T4_RTO] = 0; | |
157 | ||
158 | /* sctpimpguide Section 2.12.2 | |
159 | * If the 'T5-shutdown-guard' timer is used, it SHOULD be set to the | |
160 | * recommended value of 5 times 'RTO.Max'. | |
161 | */ | |
d808ad9a | 162 | asoc->timeouts[SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD] |
1e7d3d90 VY |
163 | = 5 * asoc->rto_max; |
164 | ||
165 | asoc->timeouts[SCTP_EVENT_TIMEOUT_HEARTBEAT] = 0; | |
52ccb8e9 | 166 | asoc->timeouts[SCTP_EVENT_TIMEOUT_SACK] = asoc->sackdelay; |
1e7d3d90 VY |
167 | asoc->timeouts[SCTP_EVENT_TIMEOUT_AUTOCLOSE] = |
168 | sp->autoclose * HZ; | |
d808ad9a | 169 | |
1e7d3d90 | 170 | /* Initilizes the timers */ |
b24b8a24 PE |
171 | for (i = SCTP_EVENT_TIMEOUT_NONE; i < SCTP_NUM_TIMEOUT_TYPES; ++i) |
172 | setup_timer(&asoc->timers[i], sctp_timer_events[i], | |
173 | (unsigned long)asoc); | |
1da177e4 LT |
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); |
a08de64d | 246 | INIT_LIST_HEAD(&asoc->asconf_ack_list); |
1da177e4 LT |
247 | |
248 | /* Make an empty list of remote transport addresses. */ | |
249 | INIT_LIST_HEAD(&asoc->peer.transport_addr_list); | |
3f7a87d2 | 250 | asoc->peer.transport_count = 0; |
1da177e4 LT |
251 | |
252 | /* RFC 2960 5.1 Normal Establishment of an Association | |
253 | * | |
254 | * After the reception of the first data chunk in an | |
255 | * association the endpoint must immediately respond with a | |
256 | * sack to acknowledge the data chunk. Subsequent | |
257 | * acknowledgements should be done as described in Section | |
258 | * 6.2. | |
259 | * | |
260 | * [We implement this by telling a new association that it | |
261 | * already received one packet.] | |
262 | */ | |
263 | asoc->peer.sack_needed = 1; | |
264 | ||
73d9c4fd VY |
265 | /* Assume that the peer will tell us if he recognizes ASCONF |
266 | * as part of INIT exchange. | |
267 | * The sctp_addip_noauth option is there for backward compatibilty | |
268 | * and will revert old behavior. | |
1da177e4 | 269 | */ |
88799fe5 | 270 | asoc->peer.asconf_capable = 0; |
73d9c4fd VY |
271 | if (sctp_addip_noauth) |
272 | asoc->peer.asconf_capable = 1; | |
1da177e4 LT |
273 | |
274 | /* Create an input queue. */ | |
275 | sctp_inq_init(&asoc->base.inqueue); | |
c4028958 | 276 | sctp_inq_set_th_handler(&asoc->base.inqueue, sctp_assoc_bh_rcv); |
1da177e4 LT |
277 | |
278 | /* Create an output queue. */ | |
279 | sctp_outq_init(asoc, &asoc->outqueue); | |
280 | ||
281 | if (!sctp_ulpq_init(&asoc->ulpq, asoc)) | |
282 | goto fail_init; | |
283 | ||
284 | /* Set up the tsn tracking. */ | |
285 | sctp_tsnmap_init(&asoc->peer.tsn_map, SCTP_TSN_MAP_SIZE, 0); | |
286 | ||
287 | asoc->need_ecne = 0; | |
288 | ||
289 | asoc->assoc_id = 0; | |
290 | ||
291 | /* Assume that peer would support both address types unless we are | |
292 | * told otherwise. | |
293 | */ | |
294 | asoc->peer.ipv4_address = 1; | |
295 | asoc->peer.ipv6_address = 1; | |
296 | INIT_LIST_HEAD(&asoc->asocs); | |
297 | ||
298 | asoc->autoclose = sp->autoclose; | |
299 | ||
300 | asoc->default_stream = sp->default_stream; | |
301 | asoc->default_ppid = sp->default_ppid; | |
302 | asoc->default_flags = sp->default_flags; | |
303 | asoc->default_context = sp->default_context; | |
304 | asoc->default_timetolive = sp->default_timetolive; | |
6ab792f5 | 305 | asoc->default_rcv_context = sp->default_rcv_context; |
1da177e4 | 306 | |
a29a5bd4 VY |
307 | /* AUTH related initializations */ |
308 | INIT_LIST_HEAD(&asoc->endpoint_shared_keys); | |
309 | err = sctp_auth_asoc_copy_shkeys(ep, asoc, gfp); | |
310 | if (err) | |
311 | goto fail_init; | |
312 | ||
313 | asoc->active_key_id = ep->active_key_id; | |
314 | asoc->asoc_shared_key = NULL; | |
315 | ||
316 | asoc->default_hmac_id = 0; | |
317 | /* Save the hmacs and chunks list into this association */ | |
318 | if (ep->auth_hmacs_list) | |
319 | memcpy(asoc->c.auth_hmacs, ep->auth_hmacs_list, | |
320 | ntohs(ep->auth_hmacs_list->param_hdr.length)); | |
321 | if (ep->auth_chunk_list) | |
322 | memcpy(asoc->c.auth_chunks, ep->auth_chunk_list, | |
323 | ntohs(ep->auth_chunk_list->param_hdr.length)); | |
324 | ||
325 | /* Get the AUTH random number for this association */ | |
326 | p = (sctp_paramhdr_t *)asoc->c.auth_random; | |
327 | p->type = SCTP_PARAM_RANDOM; | |
328 | p->length = htons(sizeof(sctp_paramhdr_t) + SCTP_AUTH_RANDOM_LENGTH); | |
329 | get_random_bytes(p+1, SCTP_AUTH_RANDOM_LENGTH); | |
330 | ||
1da177e4 LT |
331 | return asoc; |
332 | ||
333 | fail_init: | |
334 | sctp_endpoint_put(asoc->ep); | |
335 | sock_put(asoc->base.sk); | |
336 | return NULL; | |
337 | } | |
338 | ||
339 | /* Allocate and initialize a new association */ | |
340 | struct sctp_association *sctp_association_new(const struct sctp_endpoint *ep, | |
341 | const struct sock *sk, | |
3182cd84 | 342 | sctp_scope_t scope, |
dd0fc66f | 343 | gfp_t gfp) |
1da177e4 LT |
344 | { |
345 | struct sctp_association *asoc; | |
346 | ||
347 | asoc = t_new(struct sctp_association, gfp); | |
348 | if (!asoc) | |
349 | goto fail; | |
350 | ||
351 | if (!sctp_association_init(asoc, ep, sk, scope, gfp)) | |
352 | goto fail_init; | |
353 | ||
354 | asoc->base.malloced = 1; | |
355 | SCTP_DBG_OBJCNT_INC(assoc); | |
3f7a87d2 | 356 | SCTP_DEBUG_PRINTK("Created asoc %p\n", asoc); |
1da177e4 LT |
357 | |
358 | return asoc; | |
359 | ||
360 | fail_init: | |
361 | kfree(asoc); | |
362 | fail: | |
363 | return NULL; | |
364 | } | |
365 | ||
366 | /* Free this association if possible. There may still be users, so | |
367 | * the actual deallocation may be delayed. | |
368 | */ | |
369 | void sctp_association_free(struct sctp_association *asoc) | |
370 | { | |
371 | struct sock *sk = asoc->base.sk; | |
372 | struct sctp_transport *transport; | |
373 | struct list_head *pos, *temp; | |
374 | int i; | |
375 | ||
de76e695 VY |
376 | /* Only real associations count against the endpoint, so |
377 | * don't bother for if this is a temporary association. | |
378 | */ | |
379 | if (!asoc->temp) { | |
380 | list_del(&asoc->asocs); | |
381 | ||
382 | /* Decrement the backlog value for a TCP-style listening | |
383 | * socket. | |
384 | */ | |
385 | if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING)) | |
386 | sk->sk_ack_backlog--; | |
387 | } | |
1da177e4 LT |
388 | |
389 | /* Mark as dead, so other users can know this structure is | |
390 | * going away. | |
391 | */ | |
392 | asoc->base.dead = 1; | |
393 | ||
394 | /* Dispose of any data lying around in the outqueue. */ | |
395 | sctp_outq_free(&asoc->outqueue); | |
396 | ||
397 | /* Dispose of any pending messages for the upper layer. */ | |
398 | sctp_ulpq_free(&asoc->ulpq); | |
399 | ||
400 | /* Dispose of any pending chunks on the inqueue. */ | |
401 | sctp_inq_free(&asoc->base.inqueue); | |
402 | ||
403 | /* Free ssnmap storage. */ | |
404 | sctp_ssnmap_free(asoc->ssnmap); | |
405 | ||
406 | /* Clean up the bound address list. */ | |
407 | sctp_bind_addr_free(&asoc->base.bind_addr); | |
408 | ||
409 | /* Do we need to go through all of our timers and | |
410 | * delete them? To be safe we will try to delete all, but we | |
411 | * should be able to go through and make a guess based | |
412 | * on our state. | |
413 | */ | |
414 | for (i = SCTP_EVENT_TIMEOUT_NONE; i < SCTP_NUM_TIMEOUT_TYPES; ++i) { | |
415 | if (timer_pending(&asoc->timers[i]) && | |
416 | del_timer(&asoc->timers[i])) | |
417 | sctp_association_put(asoc); | |
418 | } | |
419 | ||
420 | /* Free peer's cached cookie. */ | |
a51482bd | 421 | kfree(asoc->peer.cookie); |
730fc3d0 VY |
422 | kfree(asoc->peer.peer_random); |
423 | kfree(asoc->peer.peer_chunks); | |
424 | kfree(asoc->peer.peer_hmacs); | |
1da177e4 LT |
425 | |
426 | /* Release the transport structures. */ | |
427 | list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) { | |
428 | transport = list_entry(pos, struct sctp_transport, transports); | |
429 | list_del(pos); | |
430 | sctp_transport_free(transport); | |
431 | } | |
432 | ||
3f7a87d2 FF |
433 | asoc->peer.transport_count = 0; |
434 | ||
1da177e4 | 435 | /* Free any cached ASCONF_ACK chunk. */ |
a08de64d | 436 | sctp_assoc_free_asconf_acks(asoc); |
1da177e4 LT |
437 | |
438 | /* Free any cached ASCONF chunk. */ | |
439 | if (asoc->addip_last_asconf) | |
440 | sctp_chunk_free(asoc->addip_last_asconf); | |
441 | ||
a29a5bd4 VY |
442 | /* AUTH - Free the endpoint shared keys */ |
443 | sctp_auth_destroy_keys(&asoc->endpoint_shared_keys); | |
444 | ||
445 | /* AUTH - Free the association shared key */ | |
446 | sctp_auth_key_put(asoc->asoc_shared_key); | |
447 | ||
1da177e4 LT |
448 | sctp_association_put(asoc); |
449 | } | |
450 | ||
451 | /* Cleanup and free up an association. */ | |
452 | static void sctp_association_destroy(struct sctp_association *asoc) | |
453 | { | |
454 | SCTP_ASSERT(asoc->base.dead, "Assoc is not dead", return); | |
455 | ||
456 | sctp_endpoint_put(asoc->ep); | |
457 | sock_put(asoc->base.sk); | |
458 | ||
459 | if (asoc->assoc_id != 0) { | |
460 | spin_lock_bh(&sctp_assocs_id_lock); | |
461 | idr_remove(&sctp_assocs_id, asoc->assoc_id); | |
462 | spin_unlock_bh(&sctp_assocs_id_lock); | |
463 | } | |
464 | ||
049b3ff5 NH |
465 | BUG_TRAP(!atomic_read(&asoc->rmem_alloc)); |
466 | ||
1da177e4 LT |
467 | if (asoc->base.malloced) { |
468 | kfree(asoc); | |
469 | SCTP_DBG_OBJCNT_DEC(assoc); | |
470 | } | |
471 | } | |
472 | ||
473 | /* Change the primary destination address for the peer. */ | |
474 | void sctp_assoc_set_primary(struct sctp_association *asoc, | |
475 | struct sctp_transport *transport) | |
476 | { | |
477 | asoc->peer.primary_path = transport; | |
478 | ||
479 | /* Set a default msg_name for events. */ | |
480 | memcpy(&asoc->peer.primary_addr, &transport->ipaddr, | |
481 | sizeof(union sctp_addr)); | |
482 | ||
483 | /* If the primary path is changing, assume that the | |
484 | * user wants to use this new path. | |
485 | */ | |
ad8fec17 SS |
486 | if ((transport->state == SCTP_ACTIVE) || |
487 | (transport->state == SCTP_UNKNOWN)) | |
1da177e4 LT |
488 | asoc->peer.active_path = transport; |
489 | ||
490 | /* | |
491 | * SFR-CACC algorithm: | |
492 | * Upon the receipt of a request to change the primary | |
493 | * destination address, on the data structure for the new | |
494 | * primary destination, the sender MUST do the following: | |
495 | * | |
496 | * 1) If CHANGEOVER_ACTIVE is set, then there was a switch | |
497 | * to this destination address earlier. The sender MUST set | |
498 | * CYCLING_CHANGEOVER to indicate that this switch is a | |
499 | * double switch to the same destination address. | |
500 | */ | |
501 | if (transport->cacc.changeover_active) | |
502 | transport->cacc.cycling_changeover = 1; | |
503 | ||
504 | /* 2) The sender MUST set CHANGEOVER_ACTIVE to indicate that | |
505 | * a changeover has occurred. | |
506 | */ | |
507 | transport->cacc.changeover_active = 1; | |
508 | ||
509 | /* 3) The sender MUST store the next TSN to be sent in | |
510 | * next_tsn_at_change. | |
511 | */ | |
512 | transport->cacc.next_tsn_at_change = asoc->next_tsn; | |
513 | } | |
514 | ||
3f7a87d2 FF |
515 | /* Remove a transport from an association. */ |
516 | void sctp_assoc_rm_peer(struct sctp_association *asoc, | |
517 | struct sctp_transport *peer) | |
518 | { | |
519 | struct list_head *pos; | |
520 | struct sctp_transport *transport; | |
521 | ||
522 | SCTP_DEBUG_PRINTK_IPADDR("sctp_assoc_rm_peer:association %p addr: ", | |
523 | " port: %d\n", | |
524 | asoc, | |
525 | (&peer->ipaddr), | |
b3f5b3b6 | 526 | ntohs(peer->ipaddr.v4.sin_port)); |
3f7a87d2 FF |
527 | |
528 | /* If we are to remove the current retran_path, update it | |
529 | * to the next peer before removing this peer from the list. | |
530 | */ | |
531 | if (asoc->peer.retran_path == peer) | |
532 | sctp_assoc_update_retran_path(asoc); | |
533 | ||
534 | /* Remove this peer from the list. */ | |
535 | list_del(&peer->transports); | |
536 | ||
537 | /* Get the first transport of asoc. */ | |
538 | pos = asoc->peer.transport_addr_list.next; | |
539 | transport = list_entry(pos, struct sctp_transport, transports); | |
540 | ||
541 | /* Update any entries that match the peer to be deleted. */ | |
542 | if (asoc->peer.primary_path == peer) | |
543 | sctp_assoc_set_primary(asoc, transport); | |
544 | if (asoc->peer.active_path == peer) | |
545 | asoc->peer.active_path = transport; | |
546 | if (asoc->peer.last_data_from == peer) | |
547 | asoc->peer.last_data_from = transport; | |
548 | ||
549 | /* If we remove the transport an INIT was last sent to, set it to | |
550 | * NULL. Combined with the update of the retran path above, this | |
551 | * will cause the next INIT to be sent to the next available | |
552 | * transport, maintaining the cycle. | |
553 | */ | |
554 | if (asoc->init_last_sent_to == peer) | |
555 | asoc->init_last_sent_to = NULL; | |
556 | ||
557 | asoc->peer.transport_count--; | |
558 | ||
559 | sctp_transport_free(peer); | |
560 | } | |
561 | ||
1da177e4 LT |
562 | /* Add a transport address to an association. */ |
563 | struct sctp_transport *sctp_assoc_add_peer(struct sctp_association *asoc, | |
564 | const union sctp_addr *addr, | |
dd0fc66f | 565 | const gfp_t gfp, |
3f7a87d2 | 566 | const int peer_state) |
1da177e4 LT |
567 | { |
568 | struct sctp_transport *peer; | |
569 | struct sctp_sock *sp; | |
570 | unsigned short port; | |
571 | ||
572 | sp = sctp_sk(asoc->base.sk); | |
573 | ||
574 | /* AF_INET and AF_INET6 share common port field. */ | |
4bdf4b5f | 575 | port = ntohs(addr->v4.sin_port); |
1da177e4 | 576 | |
3f7a87d2 | 577 | SCTP_DEBUG_PRINTK_IPADDR("sctp_assoc_add_peer:association %p addr: ", |
ad8fec17 | 578 | " port: %d state:%d\n", |
3f7a87d2 FF |
579 | asoc, |
580 | addr, | |
4bdf4b5f | 581 | port, |
ad8fec17 | 582 | peer_state); |
3f7a87d2 | 583 | |
1da177e4 LT |
584 | /* Set the port if it has not been set yet. */ |
585 | if (0 == asoc->peer.port) | |
586 | asoc->peer.port = port; | |
587 | ||
588 | /* Check to see if this is a duplicate. */ | |
589 | peer = sctp_assoc_lookup_paddr(asoc, addr); | |
3f7a87d2 | 590 | if (peer) { |
ad8fec17 SS |
591 | if (peer->state == SCTP_UNKNOWN) { |
592 | if (peer_state == SCTP_ACTIVE) | |
593 | peer->state = SCTP_ACTIVE; | |
594 | if (peer_state == SCTP_UNCONFIRMED) | |
595 | peer->state = SCTP_UNCONFIRMED; | |
596 | } | |
1da177e4 | 597 | return peer; |
3f7a87d2 | 598 | } |
1da177e4 LT |
599 | |
600 | peer = sctp_transport_new(addr, gfp); | |
601 | if (!peer) | |
602 | return NULL; | |
603 | ||
604 | sctp_transport_set_owner(peer, asoc); | |
605 | ||
52ccb8e9 FF |
606 | /* Initialize the peer's heartbeat interval based on the |
607 | * association configured value. | |
608 | */ | |
609 | peer->hbinterval = asoc->hbinterval; | |
610 | ||
611 | /* Set the path max_retrans. */ | |
612 | peer->pathmaxrxt = asoc->pathmaxrxt; | |
613 | ||
614 | /* Initialize the peer's SACK delay timeout based on the | |
615 | * association configured value. | |
616 | */ | |
617 | peer->sackdelay = asoc->sackdelay; | |
618 | ||
619 | /* Enable/disable heartbeat, SACK delay, and path MTU discovery | |
620 | * based on association setting. | |
621 | */ | |
622 | peer->param_flags = asoc->param_flags; | |
623 | ||
1da177e4 | 624 | /* Initialize the pmtu of the transport. */ |
52ccb8e9 FF |
625 | if (peer->param_flags & SPP_PMTUD_ENABLE) |
626 | sctp_transport_pmtu(peer); | |
627 | else if (asoc->pathmtu) | |
628 | peer->pathmtu = asoc->pathmtu; | |
629 | else | |
630 | peer->pathmtu = SCTP_DEFAULT_MAXSEGMENT; | |
1da177e4 LT |
631 | |
632 | /* If this is the first transport addr on this association, | |
633 | * initialize the association PMTU to the peer's PMTU. | |
634 | * If not and the current association PMTU is higher than the new | |
635 | * peer's PMTU, reset the association PMTU to the new peer's PMTU. | |
636 | */ | |
52ccb8e9 FF |
637 | if (asoc->pathmtu) |
638 | asoc->pathmtu = min_t(int, peer->pathmtu, asoc->pathmtu); | |
1da177e4 | 639 | else |
52ccb8e9 | 640 | asoc->pathmtu = peer->pathmtu; |
1da177e4 LT |
641 | |
642 | SCTP_DEBUG_PRINTK("sctp_assoc_add_peer:association %p PMTU set to " | |
52ccb8e9 | 643 | "%d\n", asoc, asoc->pathmtu); |
1da177e4 | 644 | |
52ccb8e9 | 645 | asoc->frag_point = sctp_frag_point(sp, asoc->pathmtu); |
1da177e4 LT |
646 | |
647 | /* The asoc->peer.port might not be meaningful yet, but | |
648 | * initialize the packet structure anyway. | |
649 | */ | |
650 | sctp_packet_init(&peer->packet, peer, asoc->base.bind_addr.port, | |
651 | asoc->peer.port); | |
652 | ||
653 | /* 7.2.1 Slow-Start | |
654 | * | |
655 | * o The initial cwnd before DATA transmission or after a sufficiently | |
656 | * long idle period MUST be set to | |
657 | * min(4*MTU, max(2*MTU, 4380 bytes)) | |
658 | * | |
659 | * o The initial value of ssthresh MAY be arbitrarily high | |
660 | * (for example, implementations MAY use the size of the | |
661 | * receiver advertised window). | |
662 | */ | |
52ccb8e9 | 663 | peer->cwnd = min(4*asoc->pathmtu, max_t(__u32, 2*asoc->pathmtu, 4380)); |
1da177e4 LT |
664 | |
665 | /* At this point, we may not have the receiver's advertised window, | |
666 | * so initialize ssthresh to the default value and it will be set | |
667 | * later when we process the INIT. | |
668 | */ | |
669 | peer->ssthresh = SCTP_DEFAULT_MAXWINDOW; | |
670 | ||
671 | peer->partial_bytes_acked = 0; | |
672 | peer->flight_size = 0; | |
673 | ||
1da177e4 LT |
674 | /* Set the transport's RTO.initial value */ |
675 | peer->rto = asoc->rto_initial; | |
676 | ||
3f7a87d2 FF |
677 | /* Set the peer's active state. */ |
678 | peer->state = peer_state; | |
679 | ||
1da177e4 LT |
680 | /* Attach the remote transport to our asoc. */ |
681 | list_add_tail(&peer->transports, &asoc->peer.transport_addr_list); | |
3f7a87d2 | 682 | asoc->peer.transport_count++; |
1da177e4 LT |
683 | |
684 | /* If we do not yet have a primary path, set one. */ | |
685 | if (!asoc->peer.primary_path) { | |
686 | sctp_assoc_set_primary(asoc, peer); | |
687 | asoc->peer.retran_path = peer; | |
688 | } | |
689 | ||
3f7a87d2 | 690 | if (asoc->peer.active_path == asoc->peer.retran_path) { |
1da177e4 | 691 | asoc->peer.retran_path = peer; |
3f7a87d2 | 692 | } |
1da177e4 LT |
693 | |
694 | return peer; | |
695 | } | |
696 | ||
697 | /* Delete a transport address from an association. */ | |
698 | void sctp_assoc_del_peer(struct sctp_association *asoc, | |
699 | const union sctp_addr *addr) | |
700 | { | |
701 | struct list_head *pos; | |
702 | struct list_head *temp; | |
1da177e4 LT |
703 | struct sctp_transport *transport; |
704 | ||
705 | list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) { | |
706 | transport = list_entry(pos, struct sctp_transport, transports); | |
707 | if (sctp_cmp_addr_exact(addr, &transport->ipaddr)) { | |
3f7a87d2 FF |
708 | /* Do book keeping for removing the peer and free it. */ |
709 | sctp_assoc_rm_peer(asoc, transport); | |
1da177e4 LT |
710 | break; |
711 | } | |
712 | } | |
1da177e4 LT |
713 | } |
714 | ||
715 | /* Lookup a transport by address. */ | |
716 | struct sctp_transport *sctp_assoc_lookup_paddr( | |
717 | const struct sctp_association *asoc, | |
718 | const union sctp_addr *address) | |
719 | { | |
720 | struct sctp_transport *t; | |
721 | struct list_head *pos; | |
722 | ||
723 | /* Cycle through all transports searching for a peer address. */ | |
724 | ||
725 | list_for_each(pos, &asoc->peer.transport_addr_list) { | |
726 | t = list_entry(pos, struct sctp_transport, transports); | |
727 | if (sctp_cmp_addr_exact(address, &t->ipaddr)) | |
728 | return t; | |
729 | } | |
730 | ||
731 | return NULL; | |
732 | } | |
733 | ||
42e30bf3 VY |
734 | /* Remove all transports except a give one */ |
735 | void sctp_assoc_del_nonprimary_peers(struct sctp_association *asoc, | |
736 | struct sctp_transport *primary) | |
737 | { | |
738 | struct sctp_transport *temp; | |
739 | struct sctp_transport *t; | |
740 | ||
741 | list_for_each_entry_safe(t, temp, &asoc->peer.transport_addr_list, | |
742 | transports) { | |
743 | /* if the current transport is not the primary one, delete it */ | |
744 | if (t != primary) | |
745 | sctp_assoc_rm_peer(asoc, t); | |
746 | } | |
747 | ||
748 | return; | |
749 | } | |
750 | ||
1da177e4 LT |
751 | /* Engage in transport control operations. |
752 | * Mark the transport up or down and send a notification to the user. | |
753 | * Select and update the new active and retran paths. | |
754 | */ | |
755 | void sctp_assoc_control_transport(struct sctp_association *asoc, | |
756 | struct sctp_transport *transport, | |
757 | sctp_transport_cmd_t command, | |
758 | sctp_sn_error_t error) | |
759 | { | |
760 | struct sctp_transport *t = NULL; | |
761 | struct sctp_transport *first; | |
762 | struct sctp_transport *second; | |
763 | struct sctp_ulpevent *event; | |
0906e20f | 764 | struct sockaddr_storage addr; |
1da177e4 LT |
765 | struct list_head *pos; |
766 | int spc_state = 0; | |
767 | ||
768 | /* Record the transition on the transport. */ | |
769 | switch (command) { | |
770 | case SCTP_TRANSPORT_UP: | |
1ae4114d VY |
771 | /* If we are moving from UNCONFIRMED state due |
772 | * to heartbeat success, report the SCTP_ADDR_CONFIRMED | |
773 | * state to the user, otherwise report SCTP_ADDR_AVAILABLE. | |
774 | */ | |
775 | if (SCTP_UNCONFIRMED == transport->state && | |
776 | SCTP_HEARTBEAT_SUCCESS == error) | |
777 | spc_state = SCTP_ADDR_CONFIRMED; | |
778 | else | |
779 | spc_state = SCTP_ADDR_AVAILABLE; | |
3f7a87d2 | 780 | transport->state = SCTP_ACTIVE; |
1da177e4 LT |
781 | break; |
782 | ||
783 | case SCTP_TRANSPORT_DOWN: | |
cc75689a VY |
784 | /* if the transort was never confirmed, do not transition it |
785 | * to inactive state. | |
786 | */ | |
787 | if (transport->state != SCTP_UNCONFIRMED) | |
788 | transport->state = SCTP_INACTIVE; | |
789 | ||
1da177e4 LT |
790 | spc_state = SCTP_ADDR_UNREACHABLE; |
791 | break; | |
792 | ||
793 | default: | |
794 | return; | |
3ff50b79 | 795 | } |
1da177e4 LT |
796 | |
797 | /* Generate and send a SCTP_PEER_ADDR_CHANGE notification to the | |
798 | * user. | |
799 | */ | |
0906e20f | 800 | memset(&addr, 0, sizeof(struct sockaddr_storage)); |
8cec6b80 | 801 | memcpy(&addr, &transport->ipaddr, transport->af_specific->sockaddr_len); |
0906e20f | 802 | event = sctp_ulpevent_make_peer_addr_change(asoc, &addr, |
1da177e4 LT |
803 | 0, spc_state, error, GFP_ATOMIC); |
804 | if (event) | |
805 | sctp_ulpq_tail_event(&asoc->ulpq, event); | |
806 | ||
807 | /* Select new active and retran paths. */ | |
808 | ||
809 | /* Look for the two most recently used active transports. | |
810 | * | |
811 | * This code produces the wrong ordering whenever jiffies | |
812 | * rolls over, but we still get usable transports, so we don't | |
813 | * worry about it. | |
814 | */ | |
815 | first = NULL; second = NULL; | |
816 | ||
817 | list_for_each(pos, &asoc->peer.transport_addr_list) { | |
818 | t = list_entry(pos, struct sctp_transport, transports); | |
819 | ||
ad8fec17 SS |
820 | if ((t->state == SCTP_INACTIVE) || |
821 | (t->state == SCTP_UNCONFIRMED)) | |
1da177e4 LT |
822 | continue; |
823 | if (!first || t->last_time_heard > first->last_time_heard) { | |
824 | second = first; | |
825 | first = t; | |
826 | } | |
827 | if (!second || t->last_time_heard > second->last_time_heard) | |
828 | second = t; | |
829 | } | |
830 | ||
831 | /* RFC 2960 6.4 Multi-Homed SCTP Endpoints | |
832 | * | |
833 | * By default, an endpoint should always transmit to the | |
834 | * primary path, unless the SCTP user explicitly specifies the | |
835 | * destination transport address (and possibly source | |
836 | * transport address) to use. | |
837 | * | |
838 | * [If the primary is active but not most recent, bump the most | |
839 | * recently used transport.] | |
840 | */ | |
ad8fec17 SS |
841 | if (((asoc->peer.primary_path->state == SCTP_ACTIVE) || |
842 | (asoc->peer.primary_path->state == SCTP_UNKNOWN)) && | |
1da177e4 LT |
843 | first != asoc->peer.primary_path) { |
844 | second = first; | |
845 | first = asoc->peer.primary_path; | |
846 | } | |
847 | ||
848 | /* If we failed to find a usable transport, just camp on the | |
849 | * primary, even if it is inactive. | |
850 | */ | |
851 | if (!first) { | |
852 | first = asoc->peer.primary_path; | |
853 | second = asoc->peer.primary_path; | |
854 | } | |
855 | ||
856 | /* Set the active and retran transports. */ | |
857 | asoc->peer.active_path = first; | |
858 | asoc->peer.retran_path = second; | |
859 | } | |
860 | ||
861 | /* Hold a reference to an association. */ | |
862 | void sctp_association_hold(struct sctp_association *asoc) | |
863 | { | |
864 | atomic_inc(&asoc->base.refcnt); | |
865 | } | |
866 | ||
867 | /* Release a reference to an association and cleanup | |
868 | * if there are no more references. | |
869 | */ | |
870 | void sctp_association_put(struct sctp_association *asoc) | |
871 | { | |
872 | if (atomic_dec_and_test(&asoc->base.refcnt)) | |
873 | sctp_association_destroy(asoc); | |
874 | } | |
875 | ||
876 | /* Allocate the next TSN, Transmission Sequence Number, for the given | |
877 | * association. | |
878 | */ | |
879 | __u32 sctp_association_get_next_tsn(struct sctp_association *asoc) | |
880 | { | |
881 | /* From Section 1.6 Serial Number Arithmetic: | |
882 | * Transmission Sequence Numbers wrap around when they reach | |
883 | * 2**32 - 1. That is, the next TSN a DATA chunk MUST use | |
884 | * after transmitting TSN = 2*32 - 1 is TSN = 0. | |
885 | */ | |
886 | __u32 retval = asoc->next_tsn; | |
887 | asoc->next_tsn++; | |
888 | asoc->unack_data++; | |
889 | ||
890 | return retval; | |
891 | } | |
892 | ||
893 | /* Compare two addresses to see if they match. Wildcard addresses | |
894 | * only match themselves. | |
895 | */ | |
896 | int sctp_cmp_addr_exact(const union sctp_addr *ss1, | |
897 | const union sctp_addr *ss2) | |
898 | { | |
899 | struct sctp_af *af; | |
900 | ||
901 | af = sctp_get_af_specific(ss1->sa.sa_family); | |
902 | if (unlikely(!af)) | |
903 | return 0; | |
904 | ||
905 | return af->cmp_addr(ss1, ss2); | |
906 | } | |
907 | ||
908 | /* Return an ecne chunk to get prepended to a packet. | |
909 | * Note: We are sly and return a shared, prealloced chunk. FIXME: | |
910 | * No we don't, but we could/should. | |
911 | */ | |
912 | struct sctp_chunk *sctp_get_ecne_prepend(struct sctp_association *asoc) | |
913 | { | |
914 | struct sctp_chunk *chunk; | |
915 | ||
916 | /* Send ECNE if needed. | |
917 | * Not being able to allocate a chunk here is not deadly. | |
918 | */ | |
919 | if (asoc->need_ecne) | |
920 | chunk = sctp_make_ecne(asoc, asoc->last_ecne_tsn); | |
921 | else | |
922 | chunk = NULL; | |
923 | ||
924 | return chunk; | |
925 | } | |
926 | ||
927 | /* | |
928 | * Find which transport this TSN was sent on. | |
929 | */ | |
930 | struct sctp_transport *sctp_assoc_lookup_tsn(struct sctp_association *asoc, | |
931 | __u32 tsn) | |
932 | { | |
933 | struct sctp_transport *active; | |
934 | struct sctp_transport *match; | |
935 | struct list_head *entry, *pos; | |
936 | struct sctp_transport *transport; | |
937 | struct sctp_chunk *chunk; | |
dbc16db1 | 938 | __be32 key = htonl(tsn); |
1da177e4 LT |
939 | |
940 | match = NULL; | |
941 | ||
942 | /* | |
943 | * FIXME: In general, find a more efficient data structure for | |
944 | * searching. | |
945 | */ | |
946 | ||
947 | /* | |
948 | * The general strategy is to search each transport's transmitted | |
949 | * list. Return which transport this TSN lives on. | |
950 | * | |
951 | * Let's be hopeful and check the active_path first. | |
952 | * Another optimization would be to know if there is only one | |
953 | * outbound path and not have to look for the TSN at all. | |
954 | * | |
955 | */ | |
956 | ||
957 | active = asoc->peer.active_path; | |
958 | ||
959 | list_for_each(entry, &active->transmitted) { | |
960 | chunk = list_entry(entry, struct sctp_chunk, transmitted_list); | |
961 | ||
962 | if (key == chunk->subh.data_hdr->tsn) { | |
963 | match = active; | |
964 | goto out; | |
965 | } | |
966 | } | |
967 | ||
968 | /* If not found, go search all the other transports. */ | |
969 | list_for_each(pos, &asoc->peer.transport_addr_list) { | |
970 | transport = list_entry(pos, struct sctp_transport, transports); | |
971 | ||
972 | if (transport == active) | |
973 | break; | |
974 | list_for_each(entry, &transport->transmitted) { | |
975 | chunk = list_entry(entry, struct sctp_chunk, | |
976 | transmitted_list); | |
977 | if (key == chunk->subh.data_hdr->tsn) { | |
978 | match = transport; | |
979 | goto out; | |
980 | } | |
981 | } | |
982 | } | |
983 | out: | |
984 | return match; | |
985 | } | |
986 | ||
987 | /* Is this the association we are looking for? */ | |
988 | struct sctp_transport *sctp_assoc_is_match(struct sctp_association *asoc, | |
989 | const union sctp_addr *laddr, | |
990 | const union sctp_addr *paddr) | |
991 | { | |
992 | struct sctp_transport *transport; | |
993 | ||
e2fccedb AV |
994 | if ((htons(asoc->base.bind_addr.port) == laddr->v4.sin_port) && |
995 | (htons(asoc->peer.port) == paddr->v4.sin_port)) { | |
1da177e4 LT |
996 | transport = sctp_assoc_lookup_paddr(asoc, paddr); |
997 | if (!transport) | |
998 | goto out; | |
999 | ||
1000 | if (sctp_bind_addr_match(&asoc->base.bind_addr, laddr, | |
1001 | sctp_sk(asoc->base.sk))) | |
1002 | goto out; | |
1003 | } | |
1004 | transport = NULL; | |
1005 | ||
1006 | out: | |
1da177e4 LT |
1007 | return transport; |
1008 | } | |
1009 | ||
1010 | /* Do delayed input processing. This is scheduled by sctp_rcv(). */ | |
c4028958 | 1011 | static void sctp_assoc_bh_rcv(struct work_struct *work) |
1da177e4 | 1012 | { |
c4028958 DH |
1013 | struct sctp_association *asoc = |
1014 | container_of(work, struct sctp_association, | |
1015 | base.inqueue.immediate); | |
1da177e4 LT |
1016 | struct sctp_endpoint *ep; |
1017 | struct sctp_chunk *chunk; | |
1018 | struct sock *sk; | |
1019 | struct sctp_inq *inqueue; | |
1020 | int state; | |
1021 | sctp_subtype_t subtype; | |
1022 | int error = 0; | |
1023 | ||
1024 | /* The association should be held so we should be safe. */ | |
1025 | ep = asoc->ep; | |
1026 | sk = asoc->base.sk; | |
1027 | ||
1028 | inqueue = &asoc->base.inqueue; | |
1029 | sctp_association_hold(asoc); | |
1030 | while (NULL != (chunk = sctp_inq_pop(inqueue))) { | |
1031 | state = asoc->state; | |
1032 | subtype = SCTP_ST_CHUNK(chunk->chunk_hdr->type); | |
1033 | ||
bbd0d598 VY |
1034 | /* SCTP-AUTH, Section 6.3: |
1035 | * The receiver has a list of chunk types which it expects | |
1036 | * to be received only after an AUTH-chunk. This list has | |
1037 | * been sent to the peer during the association setup. It | |
1038 | * MUST silently discard these chunks if they are not placed | |
1039 | * after an AUTH chunk in the packet. | |
1040 | */ | |
1041 | if (sctp_auth_recv_cid(subtype.chunk, asoc) && !chunk->auth) | |
1042 | continue; | |
1043 | ||
1da177e4 LT |
1044 | /* Remember where the last DATA chunk came from so we |
1045 | * know where to send the SACK. | |
1046 | */ | |
1047 | if (sctp_chunk_is_data(chunk)) | |
1048 | asoc->peer.last_data_from = chunk->transport; | |
1049 | else | |
1050 | SCTP_INC_STATS(SCTP_MIB_INCTRLCHUNKS); | |
1051 | ||
1052 | if (chunk->transport) | |
1053 | chunk->transport->last_time_heard = jiffies; | |
1054 | ||
1055 | /* Run through the state machine. */ | |
1056 | error = sctp_do_sm(SCTP_EVENT_T_CHUNK, subtype, | |
1057 | state, ep, asoc, chunk, GFP_ATOMIC); | |
1058 | ||
1059 | /* Check to see if the association is freed in response to | |
1060 | * the incoming chunk. If so, get out of the while loop. | |
1061 | */ | |
1062 | if (asoc->base.dead) | |
1063 | break; | |
1064 | ||
1065 | /* If there is an error on chunk, discard this packet. */ | |
1066 | if (error && chunk) | |
1067 | chunk->pdiscard = 1; | |
1068 | } | |
1069 | sctp_association_put(asoc); | |
1070 | } | |
1071 | ||
1072 | /* This routine moves an association from its old sk to a new sk. */ | |
1073 | void sctp_assoc_migrate(struct sctp_association *assoc, struct sock *newsk) | |
1074 | { | |
1075 | struct sctp_sock *newsp = sctp_sk(newsk); | |
1076 | struct sock *oldsk = assoc->base.sk; | |
1077 | ||
1078 | /* Delete the association from the old endpoint's list of | |
1079 | * associations. | |
1080 | */ | |
1081 | list_del_init(&assoc->asocs); | |
1082 | ||
1083 | /* Decrement the backlog value for a TCP-style socket. */ | |
1084 | if (sctp_style(oldsk, TCP)) | |
1085 | oldsk->sk_ack_backlog--; | |
1086 | ||
1087 | /* Release references to the old endpoint and the sock. */ | |
1088 | sctp_endpoint_put(assoc->ep); | |
1089 | sock_put(assoc->base.sk); | |
1090 | ||
1091 | /* Get a reference to the new endpoint. */ | |
1092 | assoc->ep = newsp->ep; | |
1093 | sctp_endpoint_hold(assoc->ep); | |
1094 | ||
1095 | /* Get a reference to the new sock. */ | |
1096 | assoc->base.sk = newsk; | |
1097 | sock_hold(assoc->base.sk); | |
1098 | ||
1099 | /* Add the association to the new endpoint's list of associations. */ | |
1100 | sctp_endpoint_add_asoc(newsp->ep, assoc); | |
1101 | } | |
1102 | ||
1103 | /* Update an association (possibly from unexpected COOKIE-ECHO processing). */ | |
1104 | void sctp_assoc_update(struct sctp_association *asoc, | |
1105 | struct sctp_association *new) | |
1106 | { | |
1107 | struct sctp_transport *trans; | |
1108 | struct list_head *pos, *temp; | |
1109 | ||
1110 | /* Copy in new parameters of peer. */ | |
1111 | asoc->c = new->c; | |
1112 | asoc->peer.rwnd = new->peer.rwnd; | |
1113 | asoc->peer.sack_needed = new->peer.sack_needed; | |
1114 | asoc->peer.i = new->peer.i; | |
1115 | sctp_tsnmap_init(&asoc->peer.tsn_map, SCTP_TSN_MAP_SIZE, | |
1116 | asoc->peer.i.initial_tsn); | |
1117 | ||
1118 | /* Remove any peer addresses not present in the new association. */ | |
1119 | list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) { | |
1120 | trans = list_entry(pos, struct sctp_transport, transports); | |
1121 | if (!sctp_assoc_lookup_paddr(new, &trans->ipaddr)) | |
1122 | sctp_assoc_del_peer(asoc, &trans->ipaddr); | |
749bf921 VY |
1123 | |
1124 | if (asoc->state >= SCTP_STATE_ESTABLISHED) | |
1125 | sctp_transport_reset(trans); | |
1da177e4 LT |
1126 | } |
1127 | ||
1128 | /* If the case is A (association restart), use | |
1129 | * initial_tsn as next_tsn. If the case is B, use | |
1130 | * current next_tsn in case data sent to peer | |
1131 | * has been discarded and needs retransmission. | |
1132 | */ | |
1133 | if (asoc->state >= SCTP_STATE_ESTABLISHED) { | |
1134 | asoc->next_tsn = new->next_tsn; | |
1135 | asoc->ctsn_ack_point = new->ctsn_ack_point; | |
1136 | asoc->adv_peer_ack_point = new->adv_peer_ack_point; | |
1137 | ||
1138 | /* Reinitialize SSN for both local streams | |
1139 | * and peer's streams. | |
1140 | */ | |
1141 | sctp_ssnmap_clear(asoc->ssnmap); | |
1142 | ||
0b58a811 VY |
1143 | /* Flush the ULP reassembly and ordered queue. |
1144 | * Any data there will now be stale and will | |
1145 | * cause problems. | |
1146 | */ | |
1147 | sctp_ulpq_flush(&asoc->ulpq); | |
1148 | ||
749bf921 VY |
1149 | /* reset the overall association error count so |
1150 | * that the restarted association doesn't get torn | |
1151 | * down on the next retransmission timer. | |
1152 | */ | |
1153 | asoc->overall_error_count = 0; | |
1154 | ||
1da177e4 LT |
1155 | } else { |
1156 | /* Add any peer addresses from the new association. */ | |
1157 | list_for_each(pos, &new->peer.transport_addr_list) { | |
1158 | trans = list_entry(pos, struct sctp_transport, | |
1159 | transports); | |
1160 | if (!sctp_assoc_lookup_paddr(asoc, &trans->ipaddr)) | |
1161 | sctp_assoc_add_peer(asoc, &trans->ipaddr, | |
ad8fec17 | 1162 | GFP_ATOMIC, trans->state); |
1da177e4 LT |
1163 | } |
1164 | ||
1165 | asoc->ctsn_ack_point = asoc->next_tsn - 1; | |
1166 | asoc->adv_peer_ack_point = asoc->ctsn_ack_point; | |
1167 | if (!asoc->ssnmap) { | |
1168 | /* Move the ssnmap. */ | |
1169 | asoc->ssnmap = new->ssnmap; | |
1170 | new->ssnmap = NULL; | |
1171 | } | |
07d93967 VY |
1172 | |
1173 | if (!asoc->assoc_id) { | |
1174 | /* get a new association id since we don't have one | |
1175 | * yet. | |
1176 | */ | |
1177 | sctp_assoc_set_id(asoc, GFP_ATOMIC); | |
1178 | } | |
1da177e4 | 1179 | } |
a29a5bd4 | 1180 | |
730fc3d0 VY |
1181 | /* SCTP-AUTH: Save the peer parameters from the new assocaitions |
1182 | * and also move the association shared keys over | |
1183 | */ | |
1184 | kfree(asoc->peer.peer_random); | |
1185 | asoc->peer.peer_random = new->peer.peer_random; | |
1186 | new->peer.peer_random = NULL; | |
1187 | ||
1188 | kfree(asoc->peer.peer_chunks); | |
1189 | asoc->peer.peer_chunks = new->peer.peer_chunks; | |
1190 | new->peer.peer_chunks = NULL; | |
1191 | ||
1192 | kfree(asoc->peer.peer_hmacs); | |
1193 | asoc->peer.peer_hmacs = new->peer.peer_hmacs; | |
1194 | new->peer.peer_hmacs = NULL; | |
1195 | ||
1196 | sctp_auth_key_put(asoc->asoc_shared_key); | |
1197 | sctp_auth_asoc_init_active_key(asoc, GFP_ATOMIC); | |
1da177e4 LT |
1198 | } |
1199 | ||
1200 | /* Update the retran path for sending a retransmitted packet. | |
1201 | * Round-robin through the active transports, else round-robin | |
1202 | * through the inactive transports as this is the next best thing | |
1203 | * we can try. | |
1204 | */ | |
1205 | void sctp_assoc_update_retran_path(struct sctp_association *asoc) | |
1206 | { | |
1207 | struct sctp_transport *t, *next; | |
1208 | struct list_head *head = &asoc->peer.transport_addr_list; | |
1209 | struct list_head *pos; | |
1210 | ||
1211 | /* Find the next transport in a round-robin fashion. */ | |
1212 | t = asoc->peer.retran_path; | |
1213 | pos = &t->transports; | |
1214 | next = NULL; | |
1215 | ||
1216 | while (1) { | |
1217 | /* Skip the head. */ | |
1218 | if (pos->next == head) | |
1219 | pos = head->next; | |
1220 | else | |
1221 | pos = pos->next; | |
1222 | ||
1223 | t = list_entry(pos, struct sctp_transport, transports); | |
1224 | ||
1225 | /* Try to find an active transport. */ | |
1226 | ||
ad8fec17 SS |
1227 | if ((t->state == SCTP_ACTIVE) || |
1228 | (t->state == SCTP_UNKNOWN)) { | |
1da177e4 LT |
1229 | break; |
1230 | } else { | |
1231 | /* Keep track of the next transport in case | |
1232 | * we don't find any active transport. | |
1233 | */ | |
1234 | if (!next) | |
1235 | next = t; | |
1236 | } | |
1237 | ||
1238 | /* We have exhausted the list, but didn't find any | |
1239 | * other active transports. If so, use the next | |
1240 | * transport. | |
1241 | */ | |
1242 | if (t == asoc->peer.retran_path) { | |
1243 | t = next; | |
1244 | break; | |
1245 | } | |
1246 | } | |
1247 | ||
1248 | asoc->peer.retran_path = t; | |
3f7a87d2 FF |
1249 | |
1250 | SCTP_DEBUG_PRINTK_IPADDR("sctp_assoc_update_retran_path:association" | |
1251 | " %p addr: ", | |
1252 | " port: %d\n", | |
1253 | asoc, | |
1254 | (&t->ipaddr), | |
b3f5b3b6 | 1255 | ntohs(t->ipaddr.v4.sin_port)); |
3f7a87d2 FF |
1256 | } |
1257 | ||
1258 | /* Choose the transport for sending a INIT packet. */ | |
1259 | struct sctp_transport *sctp_assoc_choose_init_transport( | |
1260 | struct sctp_association *asoc) | |
1261 | { | |
1262 | struct sctp_transport *t; | |
1263 | ||
1264 | /* Use the retran path. If the last INIT was sent over the | |
1265 | * retran path, update the retran path and use it. | |
1266 | */ | |
1267 | if (!asoc->init_last_sent_to) { | |
1268 | t = asoc->peer.active_path; | |
1269 | } else { | |
1270 | if (asoc->init_last_sent_to == asoc->peer.retran_path) | |
1271 | sctp_assoc_update_retran_path(asoc); | |
1272 | t = asoc->peer.retran_path; | |
1273 | } | |
1274 | ||
1275 | SCTP_DEBUG_PRINTK_IPADDR("sctp_assoc_update_retran_path:association" | |
1276 | " %p addr: ", | |
1277 | " port: %d\n", | |
1278 | asoc, | |
1279 | (&t->ipaddr), | |
b3f5b3b6 | 1280 | ntohs(t->ipaddr.v4.sin_port)); |
3f7a87d2 FF |
1281 | |
1282 | return t; | |
1da177e4 LT |
1283 | } |
1284 | ||
1285 | /* Choose the transport for sending a SHUTDOWN packet. */ | |
1286 | struct sctp_transport *sctp_assoc_choose_shutdown_transport( | |
1287 | struct sctp_association *asoc) | |
1288 | { | |
1289 | /* If this is the first time SHUTDOWN is sent, use the active path, | |
1290 | * else use the retran path. If the last SHUTDOWN was sent over the | |
1291 | * retran path, update the retran path and use it. | |
1292 | */ | |
1293 | if (!asoc->shutdown_last_sent_to) | |
1294 | return asoc->peer.active_path; | |
1295 | else { | |
1296 | if (asoc->shutdown_last_sent_to == asoc->peer.retran_path) | |
1297 | sctp_assoc_update_retran_path(asoc); | |
1298 | return asoc->peer.retran_path; | |
1299 | } | |
1300 | ||
1301 | } | |
1302 | ||
1303 | /* Update the association's pmtu and frag_point by going through all the | |
1304 | * transports. This routine is called when a transport's PMTU has changed. | |
1305 | */ | |
1306 | void sctp_assoc_sync_pmtu(struct sctp_association *asoc) | |
1307 | { | |
1308 | struct sctp_transport *t; | |
1309 | struct list_head *pos; | |
1310 | __u32 pmtu = 0; | |
1311 | ||
1312 | if (!asoc) | |
1313 | return; | |
1314 | ||
1315 | /* Get the lowest pmtu of all the transports. */ | |
1316 | list_for_each(pos, &asoc->peer.transport_addr_list) { | |
1317 | t = list_entry(pos, struct sctp_transport, transports); | |
8a479491 VY |
1318 | if (t->pmtu_pending && t->dst) { |
1319 | sctp_transport_update_pmtu(t, dst_mtu(t->dst)); | |
1320 | t->pmtu_pending = 0; | |
1321 | } | |
52ccb8e9 FF |
1322 | if (!pmtu || (t->pathmtu < pmtu)) |
1323 | pmtu = t->pathmtu; | |
1da177e4 LT |
1324 | } |
1325 | ||
1326 | if (pmtu) { | |
1327 | struct sctp_sock *sp = sctp_sk(asoc->base.sk); | |
52ccb8e9 | 1328 | asoc->pathmtu = pmtu; |
1da177e4 LT |
1329 | asoc->frag_point = sctp_frag_point(sp, pmtu); |
1330 | } | |
1331 | ||
1332 | SCTP_DEBUG_PRINTK("%s: asoc:%p, pmtu:%d, frag_point:%d\n", | |
0dc47877 | 1333 | __func__, asoc, asoc->pathmtu, asoc->frag_point); |
1da177e4 LT |
1334 | } |
1335 | ||
1336 | /* Should we send a SACK to update our peer? */ | |
1337 | static inline int sctp_peer_needs_update(struct sctp_association *asoc) | |
1338 | { | |
1339 | switch (asoc->state) { | |
1340 | case SCTP_STATE_ESTABLISHED: | |
1341 | case SCTP_STATE_SHUTDOWN_PENDING: | |
1342 | case SCTP_STATE_SHUTDOWN_RECEIVED: | |
1343 | case SCTP_STATE_SHUTDOWN_SENT: | |
1344 | if ((asoc->rwnd > asoc->a_rwnd) && | |
1345 | ((asoc->rwnd - asoc->a_rwnd) >= | |
52ccb8e9 | 1346 | min_t(__u32, (asoc->base.sk->sk_rcvbuf >> 1), asoc->pathmtu))) |
1da177e4 LT |
1347 | return 1; |
1348 | break; | |
1349 | default: | |
1350 | break; | |
1351 | } | |
1352 | return 0; | |
1353 | } | |
1354 | ||
1355 | /* Increase asoc's rwnd by len and send any window update SACK if needed. */ | |
1356 | void sctp_assoc_rwnd_increase(struct sctp_association *asoc, unsigned len) | |
1357 | { | |
1358 | struct sctp_chunk *sack; | |
1359 | struct timer_list *timer; | |
1360 | ||
1361 | if (asoc->rwnd_over) { | |
1362 | if (asoc->rwnd_over >= len) { | |
1363 | asoc->rwnd_over -= len; | |
1364 | } else { | |
1365 | asoc->rwnd += (len - asoc->rwnd_over); | |
1366 | asoc->rwnd_over = 0; | |
1367 | } | |
1368 | } else { | |
1369 | asoc->rwnd += len; | |
1370 | } | |
1371 | ||
1372 | SCTP_DEBUG_PRINTK("%s: asoc %p rwnd increased by %d to (%u, %u) " | |
0dc47877 | 1373 | "- %u\n", __func__, asoc, len, asoc->rwnd, |
1da177e4 LT |
1374 | asoc->rwnd_over, asoc->a_rwnd); |
1375 | ||
1376 | /* Send a window update SACK if the rwnd has increased by at least the | |
1377 | * minimum of the association's PMTU and half of the receive buffer. | |
1378 | * The algorithm used is similar to the one described in | |
1379 | * Section 4.2.3.3 of RFC 1122. | |
1380 | */ | |
1381 | if (sctp_peer_needs_update(asoc)) { | |
1382 | asoc->a_rwnd = asoc->rwnd; | |
1383 | SCTP_DEBUG_PRINTK("%s: Sending window update SACK- asoc: %p " | |
0dc47877 | 1384 | "rwnd: %u a_rwnd: %u\n", __func__, |
1da177e4 LT |
1385 | asoc, asoc->rwnd, asoc->a_rwnd); |
1386 | sack = sctp_make_sack(asoc); | |
1387 | if (!sack) | |
1388 | return; | |
1389 | ||
1390 | asoc->peer.sack_needed = 0; | |
1391 | ||
1392 | sctp_outq_tail(&asoc->outqueue, sack); | |
1393 | ||
1394 | /* Stop the SACK timer. */ | |
1395 | timer = &asoc->timers[SCTP_EVENT_TIMEOUT_SACK]; | |
1396 | if (timer_pending(timer) && del_timer(timer)) | |
1397 | sctp_association_put(asoc); | |
1398 | } | |
1399 | } | |
1400 | ||
1401 | /* Decrease asoc's rwnd by len. */ | |
1402 | void sctp_assoc_rwnd_decrease(struct sctp_association *asoc, unsigned len) | |
1403 | { | |
1404 | SCTP_ASSERT(asoc->rwnd, "rwnd zero", return); | |
1405 | SCTP_ASSERT(!asoc->rwnd_over, "rwnd_over not zero", return); | |
1406 | if (asoc->rwnd >= len) { | |
1407 | asoc->rwnd -= len; | |
1408 | } else { | |
1409 | asoc->rwnd_over = len - asoc->rwnd; | |
1410 | asoc->rwnd = 0; | |
1411 | } | |
1412 | SCTP_DEBUG_PRINTK("%s: asoc %p rwnd decreased by %d to (%u, %u)\n", | |
0dc47877 | 1413 | __func__, asoc, len, asoc->rwnd, |
1da177e4 LT |
1414 | asoc->rwnd_over); |
1415 | } | |
1416 | ||
1417 | /* Build the bind address list for the association based on info from the | |
1418 | * local endpoint and the remote peer. | |
1419 | */ | |
3182cd84 | 1420 | int sctp_assoc_set_bind_addr_from_ep(struct sctp_association *asoc, |
dd0fc66f | 1421 | gfp_t gfp) |
1da177e4 LT |
1422 | { |
1423 | sctp_scope_t scope; | |
1424 | int flags; | |
1425 | ||
1426 | /* Use scoping rules to determine the subset of addresses from | |
1427 | * the endpoint. | |
1428 | */ | |
1429 | scope = sctp_scope(&asoc->peer.active_path->ipaddr); | |
1430 | flags = (PF_INET6 == asoc->base.sk->sk_family) ? SCTP_ADDR6_ALLOWED : 0; | |
1431 | if (asoc->peer.ipv4_address) | |
1432 | flags |= SCTP_ADDR4_PEERSUPP; | |
1433 | if (asoc->peer.ipv6_address) | |
1434 | flags |= SCTP_ADDR6_PEERSUPP; | |
1435 | ||
1436 | return sctp_bind_addr_copy(&asoc->base.bind_addr, | |
1437 | &asoc->ep->base.bind_addr, | |
1438 | scope, gfp, flags); | |
1439 | } | |
1440 | ||
1441 | /* Build the association's bind address list from the cookie. */ | |
1442 | int sctp_assoc_set_bind_addr_from_cookie(struct sctp_association *asoc, | |
3182cd84 | 1443 | struct sctp_cookie *cookie, |
dd0fc66f | 1444 | gfp_t gfp) |
1da177e4 LT |
1445 | { |
1446 | int var_size2 = ntohs(cookie->peer_init->chunk_hdr.length); | |
1447 | int var_size3 = cookie->raw_addr_list_len; | |
1448 | __u8 *raw = (__u8 *)cookie->peer_init + var_size2; | |
1449 | ||
1450 | return sctp_raw_to_bind_addrs(&asoc->base.bind_addr, raw, var_size3, | |
1451 | asoc->ep->base.bind_addr.port, gfp); | |
1452 | } | |
1453 | ||
d808ad9a YH |
1454 | /* Lookup laddr in the bind address list of an association. */ |
1455 | int sctp_assoc_lookup_laddr(struct sctp_association *asoc, | |
1da177e4 LT |
1456 | const union sctp_addr *laddr) |
1457 | { | |
559cf710 | 1458 | int found = 0; |
1da177e4 | 1459 | |
1da177e4 LT |
1460 | if ((asoc->base.bind_addr.port == ntohs(laddr->v4.sin_port)) && |
1461 | sctp_bind_addr_match(&asoc->base.bind_addr, laddr, | |
559cf710 | 1462 | sctp_sk(asoc->base.sk))) |
1da177e4 | 1463 | found = 1; |
1da177e4 | 1464 | |
1da177e4 LT |
1465 | return found; |
1466 | } | |
07d93967 VY |
1467 | |
1468 | /* Set an association id for a given association */ | |
1469 | int sctp_assoc_set_id(struct sctp_association *asoc, gfp_t gfp) | |
1470 | { | |
1471 | int assoc_id; | |
1472 | int error = 0; | |
1473 | retry: | |
1474 | if (unlikely(!idr_pre_get(&sctp_assocs_id, gfp))) | |
1475 | return -ENOMEM; | |
1476 | ||
1477 | spin_lock_bh(&sctp_assocs_id_lock); | |
1478 | error = idr_get_new_above(&sctp_assocs_id, (void *)asoc, | |
1479 | 1, &assoc_id); | |
1480 | spin_unlock_bh(&sctp_assocs_id_lock); | |
1481 | if (error == -EAGAIN) | |
1482 | goto retry; | |
1483 | else if (error) | |
1484 | return error; | |
1485 | ||
1486 | asoc->assoc_id = (sctp_assoc_t) assoc_id; | |
1487 | return error; | |
1488 | } | |
a08de64d VY |
1489 | |
1490 | /* Free asconf_ack cache */ | |
1491 | static void sctp_assoc_free_asconf_acks(struct sctp_association *asoc) | |
1492 | { | |
1493 | struct sctp_chunk *ack; | |
1494 | struct sctp_chunk *tmp; | |
1495 | ||
1496 | list_for_each_entry_safe(ack, tmp, &asoc->asconf_ack_list, | |
1497 | transmitted_list) { | |
1498 | list_del_init(&ack->transmitted_list); | |
1499 | sctp_chunk_free(ack); | |
1500 | } | |
1501 | } | |
1502 | ||
1503 | /* Clean up the ASCONF_ACK queue */ | |
1504 | void sctp_assoc_clean_asconf_ack_cache(const struct sctp_association *asoc) | |
1505 | { | |
1506 | struct sctp_chunk *ack; | |
1507 | struct sctp_chunk *tmp; | |
1508 | ||
1509 | /* We can remove all the entries from the queue upto | |
1510 | * the "Peer-Sequence-Number". | |
1511 | */ | |
1512 | list_for_each_entry_safe(ack, tmp, &asoc->asconf_ack_list, | |
1513 | transmitted_list) { | |
1514 | if (ack->subh.addip_hdr->serial == | |
1515 | htonl(asoc->peer.addip_serial)) | |
1516 | break; | |
1517 | ||
1518 | list_del_init(&ack->transmitted_list); | |
1519 | sctp_chunk_free(ack); | |
1520 | } | |
1521 | } | |
1522 | ||
1523 | /* Find the ASCONF_ACK whose serial number matches ASCONF */ | |
1524 | struct sctp_chunk *sctp_assoc_lookup_asconf_ack( | |
1525 | const struct sctp_association *asoc, | |
1526 | __be32 serial) | |
1527 | { | |
a8699814 | 1528 | struct sctp_chunk *ack; |
a08de64d VY |
1529 | |
1530 | /* Walk through the list of cached ASCONF-ACKs and find the | |
1531 | * ack chunk whose serial number matches that of the request. | |
1532 | */ | |
1533 | list_for_each_entry(ack, &asoc->asconf_ack_list, transmitted_list) { | |
1534 | if (ack->subh.addip_hdr->serial == serial) { | |
1535 | sctp_chunk_hold(ack); | |
a8699814 | 1536 | return ack; |
a08de64d VY |
1537 | } |
1538 | } | |
1539 | ||
a8699814 | 1540 | return NULL; |
a08de64d | 1541 | } |