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60c778b2 | 1 | /* SCTP kernel implementation |
1da177e4 LT |
2 | * (C) Copyright IBM Corp. 2001, 2004 |
3 | * Copyright (c) 1999-2000 Cisco, Inc. | |
4 | * Copyright (c) 1999-2001 Motorola, Inc. | |
5 | * Copyright (c) 2001 Intel Corp. | |
6 | * Copyright (c) 2001 La Monte H.P. Yarroll | |
7 | * | |
60c778b2 | 8 | * This file is part of the SCTP kernel implementation |
1da177e4 LT |
9 | * |
10 | * This module provides the abstraction for an SCTP association. | |
11 | * | |
60c778b2 | 12 | * This SCTP implementation is free software; |
1da177e4 LT |
13 | * you can redistribute it and/or modify it under the terms of |
14 | * the GNU General Public License as published by | |
15 | * the Free Software Foundation; either version 2, or (at your option) | |
16 | * any later version. | |
17 | * | |
60c778b2 | 18 | * This SCTP implementation is distributed in the hope that it |
1da177e4 LT |
19 | * will be useful, but WITHOUT ANY WARRANTY; without even the implied |
20 | * ************************ | |
21 | * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. | |
22 | * See the GNU General Public License for more details. | |
23 | * | |
24 | * You should have received a copy of the GNU General Public License | |
4b2f13a2 JK |
25 | * along with GNU CC; see the file COPYING. If not, see |
26 | * <http://www.gnu.org/licenses/>. | |
1da177e4 LT |
27 | * |
28 | * Please send any bug reports or fixes you make to the | |
29 | * email address(es): | |
91705c61 | 30 | * lksctp developers <linux-sctp@vger.kernel.org> |
1da177e4 | 31 | * |
1da177e4 LT |
32 | * Written or modified by: |
33 | * La Monte H.P. Yarroll <piggy@acm.org> | |
34 | * Karl Knutson <karl@athena.chicago.il.us> | |
35 | * Jon Grimm <jgrimm@us.ibm.com> | |
36 | * Xingang Guo <xingang.guo@intel.com> | |
37 | * Hui Huang <hui.huang@nokia.com> | |
38 | * Sridhar Samudrala <sri@us.ibm.com> | |
39 | * Daisy Chang <daisyc@us.ibm.com> | |
40 | * Ryan Layer <rmlayer@us.ibm.com> | |
41 | * Kevin Gao <kevin.gao@intel.com> | |
1da177e4 LT |
42 | */ |
43 | ||
145ce502 JP |
44 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
45 | ||
1da177e4 LT |
46 | #include <linux/types.h> |
47 | #include <linux/fcntl.h> | |
48 | #include <linux/poll.h> | |
49 | #include <linux/init.h> | |
1da177e4 LT |
50 | |
51 | #include <linux/slab.h> | |
52 | #include <linux/in.h> | |
53 | #include <net/ipv6.h> | |
54 | #include <net/sctp/sctp.h> | |
55 | #include <net/sctp/sm.h> | |
56 | ||
57 | /* Forward declarations for internal functions. */ | |
b82e8f31 | 58 | static void sctp_select_active_and_retran_path(struct sctp_association *asoc); |
c4028958 | 59 | static void sctp_assoc_bh_rcv(struct work_struct *work); |
a08de64d | 60 | static void sctp_assoc_free_asconf_acks(struct sctp_association *asoc); |
8b4472cc | 61 | static void sctp_assoc_free_asconf_queue(struct sctp_association *asoc); |
1da177e4 | 62 | |
1da177e4 LT |
63 | /* 1st Level Abstractions. */ |
64 | ||
65 | /* Initialize a new association from provided memory. */ | |
1c662018 XL |
66 | static struct sctp_association *sctp_association_init( |
67 | struct sctp_association *asoc, | |
68 | const struct sctp_endpoint *ep, | |
69 | const struct sock *sk, | |
70 | enum sctp_scope scope, gfp_t gfp) | |
1da177e4 | 71 | { |
e1fc3b14 | 72 | struct net *net = sock_net(sk); |
1da177e4 | 73 | struct sctp_sock *sp; |
3c918704 | 74 | struct sctp_paramhdr *p; |
58194778 | 75 | int i; |
1da177e4 LT |
76 | |
77 | /* Retrieve the SCTP per socket area. */ | |
78 | sp = sctp_sk((struct sock *)sk); | |
79 | ||
1da177e4 LT |
80 | /* Discarding const is appropriate here. */ |
81 | asoc->ep = (struct sctp_endpoint *)ep; | |
1da177e4 | 82 | asoc->base.sk = (struct sock *)sk; |
2e0c9e79 DB |
83 | |
84 | sctp_endpoint_hold(asoc->ep); | |
1da177e4 LT |
85 | sock_hold(asoc->base.sk); |
86 | ||
87 | /* Initialize the common base substructure. */ | |
88 | asoc->base.type = SCTP_EP_TYPE_ASSOCIATION; | |
89 | ||
90 | /* Initialize the object handling fields. */ | |
c638457a | 91 | refcount_set(&asoc->base.refcnt, 1); |
1da177e4 LT |
92 | |
93 | /* Initialize the bind addr area. */ | |
94 | sctp_bind_addr_init(&asoc->base.bind_addr, ep->base.bind_addr.port); | |
1da177e4 LT |
95 | |
96 | asoc->state = SCTP_STATE_CLOSED; | |
52db882f | 97 | asoc->cookie_life = ms_to_ktime(sp->assocparams.sasoc_cookie_life); |
f68b2e05 | 98 | asoc->user_frag = sp->user_frag; |
1da177e4 LT |
99 | |
100 | /* Set the association max_retrans and RTO values from the | |
101 | * socket values. | |
102 | */ | |
103 | asoc->max_retrans = sp->assocparams.sasoc_asocmaxrxt; | |
e1fc3b14 | 104 | asoc->pf_retrans = net->sctp.pf_retrans; |
5aa93bcf | 105 | |
1da177e4 LT |
106 | asoc->rto_initial = msecs_to_jiffies(sp->rtoinfo.srto_initial); |
107 | asoc->rto_max = msecs_to_jiffies(sp->rtoinfo.srto_max); | |
108 | asoc->rto_min = msecs_to_jiffies(sp->rtoinfo.srto_min); | |
109 | ||
52ccb8e9 FF |
110 | /* Initialize the association's heartbeat interval based on the |
111 | * sock configured value. | |
112 | */ | |
113 | asoc->hbinterval = msecs_to_jiffies(sp->hbinterval); | |
114 | ||
115 | /* Initialize path max retrans value. */ | |
116 | asoc->pathmaxrxt = sp->pathmaxrxt; | |
117 | ||
8a9c58d2 XL |
118 | asoc->flowlabel = sp->flowlabel; |
119 | asoc->dscp = sp->dscp; | |
120 | ||
52ccb8e9 FF |
121 | /* Set association default SACK delay */ |
122 | asoc->sackdelay = msecs_to_jiffies(sp->sackdelay); | |
d364d927 | 123 | asoc->sackfreq = sp->sackfreq; |
52ccb8e9 FF |
124 | |
125 | /* Set the association default flags controlling | |
126 | * Heartbeat, SACK delay, and Path MTU Discovery. | |
127 | */ | |
128 | asoc->param_flags = sp->param_flags; | |
129 | ||
9d2c881a | 130 | /* Initialize the maximum number of new data packets that can be sent |
1da177e4 LT |
131 | * in a burst. |
132 | */ | |
70331571 | 133 | asoc->max_burst = sp->max_burst; |
1da177e4 | 134 | |
a1e3a059 XL |
135 | asoc->subscribe = sp->subscribe; |
136 | ||
1e7d3d90 | 137 | /* initialize association timers */ |
1e7d3d90 VY |
138 | asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_COOKIE] = asoc->rto_initial; |
139 | asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_INIT] = asoc->rto_initial; | |
140 | asoc->timeouts[SCTP_EVENT_TIMEOUT_T2_SHUTDOWN] = asoc->rto_initial; | |
1e7d3d90 VY |
141 | |
142 | /* sctpimpguide Section 2.12.2 | |
143 | * If the 'T5-shutdown-guard' timer is used, it SHOULD be set to the | |
144 | * recommended value of 5 times 'RTO.Max'. | |
145 | */ | |
d808ad9a | 146 | asoc->timeouts[SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD] |
1e7d3d90 VY |
147 | = 5 * asoc->rto_max; |
148 | ||
52ccb8e9 | 149 | asoc->timeouts[SCTP_EVENT_TIMEOUT_SACK] = asoc->sackdelay; |
9f70f46b | 150 | asoc->timeouts[SCTP_EVENT_TIMEOUT_AUTOCLOSE] = sp->autoclose * HZ; |
d808ad9a | 151 | |
421f91d2 | 152 | /* Initializes the timers */ |
b24b8a24 | 153 | for (i = SCTP_EVENT_TIMEOUT_NONE; i < SCTP_NUM_TIMEOUT_TYPES; ++i) |
9c3b5751 | 154 | timer_setup(&asoc->timers[i], sctp_timer_events[i], 0); |
1da177e4 LT |
155 | |
156 | /* Pull default initialization values from the sock options. | |
157 | * Note: This assumes that the values have already been | |
158 | * validated in the sock. | |
159 | */ | |
160 | asoc->c.sinit_max_instreams = sp->initmsg.sinit_max_instreams; | |
161 | asoc->c.sinit_num_ostreams = sp->initmsg.sinit_num_ostreams; | |
162 | asoc->max_init_attempts = sp->initmsg.sinit_max_attempts; | |
163 | ||
164 | asoc->max_init_timeo = | |
165 | msecs_to_jiffies(sp->initmsg.sinit_max_init_timeo); | |
166 | ||
1da177e4 LT |
167 | /* Set the local window size for receive. |
168 | * This is also the rcvbuf space per association. | |
169 | * RFC 6 - A SCTP receiver MUST be able to receive a minimum of | |
170 | * 1500 bytes in one SCTP packet. | |
171 | */ | |
049b3ff5 | 172 | if ((sk->sk_rcvbuf/2) < SCTP_DEFAULT_MINWINDOW) |
1da177e4 LT |
173 | asoc->rwnd = SCTP_DEFAULT_MINWINDOW; |
174 | else | |
049b3ff5 | 175 | asoc->rwnd = sk->sk_rcvbuf/2; |
1da177e4 LT |
176 | |
177 | asoc->a_rwnd = asoc->rwnd; | |
178 | ||
1da177e4 LT |
179 | /* Use my own max window until I learn something better. */ |
180 | asoc->peer.rwnd = SCTP_DEFAULT_MAXWINDOW; | |
181 | ||
049b3ff5 NH |
182 | /* Initialize the receive memory counter */ |
183 | atomic_set(&asoc->rmem_alloc, 0); | |
184 | ||
1da177e4 LT |
185 | init_waitqueue_head(&asoc->wait); |
186 | ||
187 | asoc->c.my_vtag = sctp_generate_tag(ep); | |
1da177e4 LT |
188 | asoc->c.my_port = ep->base.bind_addr.port; |
189 | ||
190 | asoc->c.initial_tsn = sctp_generate_tsn(ep); | |
191 | ||
192 | asoc->next_tsn = asoc->c.initial_tsn; | |
193 | ||
194 | asoc->ctsn_ack_point = asoc->next_tsn - 1; | |
195 | asoc->adv_peer_ack_point = asoc->ctsn_ack_point; | |
196 | asoc->highest_sacked = asoc->ctsn_ack_point; | |
197 | asoc->last_cwr_tsn = asoc->ctsn_ack_point; | |
1da177e4 | 198 | |
1da177e4 LT |
199 | /* ADDIP Section 4.1 Asconf Chunk Procedures |
200 | * | |
201 | * When an endpoint has an ASCONF signaled change to be sent to the | |
202 | * remote endpoint it should do the following: | |
203 | * ... | |
204 | * A2) a serial number should be assigned to the chunk. The serial | |
205 | * number SHOULD be a monotonically increasing number. The serial | |
206 | * numbers SHOULD be initialized at the start of the | |
207 | * association to the same value as the initial TSN. | |
208 | */ | |
209 | asoc->addip_serial = asoc->c.initial_tsn; | |
cc16f00f | 210 | asoc->strreset_outseq = asoc->c.initial_tsn; |
1da177e4 | 211 | |
79af02c2 | 212 | INIT_LIST_HEAD(&asoc->addip_chunk_list); |
a08de64d | 213 | INIT_LIST_HEAD(&asoc->asconf_ack_list); |
1da177e4 LT |
214 | |
215 | /* Make an empty list of remote transport addresses. */ | |
216 | INIT_LIST_HEAD(&asoc->peer.transport_addr_list); | |
217 | ||
218 | /* RFC 2960 5.1 Normal Establishment of an Association | |
219 | * | |
220 | * After the reception of the first data chunk in an | |
221 | * association the endpoint must immediately respond with a | |
222 | * sack to acknowledge the data chunk. Subsequent | |
223 | * acknowledgements should be done as described in Section | |
224 | * 6.2. | |
225 | * | |
226 | * [We implement this by telling a new association that it | |
227 | * already received one packet.] | |
228 | */ | |
229 | asoc->peer.sack_needed = 1; | |
4244854d | 230 | asoc->peer.sack_generation = 1; |
1da177e4 | 231 | |
73d9c4fd VY |
232 | /* Assume that the peer will tell us if he recognizes ASCONF |
233 | * as part of INIT exchange. | |
9d2c881a | 234 | * The sctp_addip_noauth option is there for backward compatibility |
73d9c4fd | 235 | * and will revert old behavior. |
1da177e4 | 236 | */ |
e1fc3b14 | 237 | if (net->sctp.addip_noauth) |
73d9c4fd | 238 | asoc->peer.asconf_capable = 1; |
1da177e4 LT |
239 | |
240 | /* Create an input queue. */ | |
241 | sctp_inq_init(&asoc->base.inqueue); | |
c4028958 | 242 | sctp_inq_set_th_handler(&asoc->base.inqueue, sctp_assoc_bh_rcv); |
1da177e4 LT |
243 | |
244 | /* Create an output queue. */ | |
245 | sctp_outq_init(asoc, &asoc->outqueue); | |
246 | ||
247 | if (!sctp_ulpq_init(&asoc->ulpq, asoc)) | |
248 | goto fail_init; | |
249 | ||
ff356414 XL |
250 | if (sctp_stream_init(&asoc->stream, asoc->c.sinit_num_ostreams, |
251 | 0, gfp)) | |
3dbcc105 XL |
252 | goto fail_init; |
253 | ||
4135cce7 XL |
254 | /* Initialize default path MTU. */ |
255 | asoc->pathmtu = sp->pathmtu; | |
256 | sctp_assoc_update_frag_point(asoc); | |
257 | ||
1da177e4 LT |
258 | /* Assume that peer would support both address types unless we are |
259 | * told otherwise. | |
260 | */ | |
261 | asoc->peer.ipv4_address = 1; | |
a2c39584 WY |
262 | if (asoc->base.sk->sk_family == PF_INET6) |
263 | asoc->peer.ipv6_address = 1; | |
1da177e4 LT |
264 | INIT_LIST_HEAD(&asoc->asocs); |
265 | ||
1da177e4 LT |
266 | asoc->default_stream = sp->default_stream; |
267 | asoc->default_ppid = sp->default_ppid; | |
268 | asoc->default_flags = sp->default_flags; | |
269 | asoc->default_context = sp->default_context; | |
270 | asoc->default_timetolive = sp->default_timetolive; | |
6ab792f5 | 271 | asoc->default_rcv_context = sp->default_rcv_context; |
1da177e4 | 272 | |
a29a5bd4 VY |
273 | /* AUTH related initializations */ |
274 | INIT_LIST_HEAD(&asoc->endpoint_shared_keys); | |
58194778 | 275 | if (sctp_auth_asoc_copy_shkeys(ep, asoc, gfp)) |
3dbcc105 | 276 | goto stream_free; |
a29a5bd4 VY |
277 | |
278 | asoc->active_key_id = ep->active_key_id; | |
28aa4c26 | 279 | asoc->prsctp_enable = ep->prsctp_enable; |
c28445c3 | 280 | asoc->reconf_enable = ep->reconf_enable; |
9fb657ae | 281 | asoc->strreset_enable = ep->strreset_enable; |
a29a5bd4 | 282 | |
a29a5bd4 VY |
283 | /* Save the hmacs and chunks list into this association */ |
284 | if (ep->auth_hmacs_list) | |
285 | memcpy(asoc->c.auth_hmacs, ep->auth_hmacs_list, | |
286 | ntohs(ep->auth_hmacs_list->param_hdr.length)); | |
287 | if (ep->auth_chunk_list) | |
288 | memcpy(asoc->c.auth_chunks, ep->auth_chunk_list, | |
289 | ntohs(ep->auth_chunk_list->param_hdr.length)); | |
290 | ||
291 | /* Get the AUTH random number for this association */ | |
3c918704 | 292 | p = (struct sctp_paramhdr *)asoc->c.auth_random; |
a29a5bd4 | 293 | p->type = SCTP_PARAM_RANDOM; |
3c918704 | 294 | p->length = htons(sizeof(*p) + SCTP_AUTH_RANDOM_LENGTH); |
a29a5bd4 VY |
295 | get_random_bytes(p+1, SCTP_AUTH_RANDOM_LENGTH); |
296 | ||
1da177e4 LT |
297 | return asoc; |
298 | ||
3dbcc105 | 299 | stream_free: |
cee360ab | 300 | sctp_stream_free(&asoc->stream); |
1da177e4 | 301 | fail_init: |
1da177e4 | 302 | sock_put(asoc->base.sk); |
2e0c9e79 | 303 | sctp_endpoint_put(asoc->ep); |
1da177e4 LT |
304 | return NULL; |
305 | } | |
306 | ||
307 | /* Allocate and initialize a new association */ | |
308 | struct sctp_association *sctp_association_new(const struct sctp_endpoint *ep, | |
1c662018 XL |
309 | const struct sock *sk, |
310 | enum sctp_scope scope, gfp_t gfp) | |
1da177e4 LT |
311 | { |
312 | struct sctp_association *asoc; | |
313 | ||
939cfa75 | 314 | asoc = kzalloc(sizeof(*asoc), gfp); |
1da177e4 LT |
315 | if (!asoc) |
316 | goto fail; | |
317 | ||
318 | if (!sctp_association_init(asoc, ep, sk, scope, gfp)) | |
319 | goto fail_init; | |
320 | ||
1da177e4 | 321 | SCTP_DBG_OBJCNT_INC(assoc); |
bb33381d DB |
322 | |
323 | pr_debug("Created asoc %p\n", asoc); | |
1da177e4 LT |
324 | |
325 | return asoc; | |
326 | ||
327 | fail_init: | |
328 | kfree(asoc); | |
329 | fail: | |
330 | return NULL; | |
331 | } | |
332 | ||
333 | /* Free this association if possible. There may still be users, so | |
334 | * the actual deallocation may be delayed. | |
335 | */ | |
336 | void sctp_association_free(struct sctp_association *asoc) | |
337 | { | |
338 | struct sock *sk = asoc->base.sk; | |
339 | struct sctp_transport *transport; | |
340 | struct list_head *pos, *temp; | |
341 | int i; | |
342 | ||
de76e695 VY |
343 | /* Only real associations count against the endpoint, so |
344 | * don't bother for if this is a temporary association. | |
345 | */ | |
d3217b15 | 346 | if (!list_empty(&asoc->asocs)) { |
de76e695 VY |
347 | list_del(&asoc->asocs); |
348 | ||
349 | /* Decrement the backlog value for a TCP-style listening | |
350 | * socket. | |
351 | */ | |
352 | if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING)) | |
353 | sk->sk_ack_backlog--; | |
354 | } | |
1da177e4 LT |
355 | |
356 | /* Mark as dead, so other users can know this structure is | |
357 | * going away. | |
358 | */ | |
0022d2dd | 359 | asoc->base.dead = true; |
1da177e4 LT |
360 | |
361 | /* Dispose of any data lying around in the outqueue. */ | |
362 | sctp_outq_free(&asoc->outqueue); | |
363 | ||
364 | /* Dispose of any pending messages for the upper layer. */ | |
365 | sctp_ulpq_free(&asoc->ulpq); | |
366 | ||
367 | /* Dispose of any pending chunks on the inqueue. */ | |
368 | sctp_inq_free(&asoc->base.inqueue); | |
369 | ||
8e1ee18c VY |
370 | sctp_tsnmap_free(&asoc->peer.tsn_map); |
371 | ||
a8386317 | 372 | /* Free stream information. */ |
cee360ab | 373 | sctp_stream_free(&asoc->stream); |
1da177e4 | 374 | |
7b9438de XL |
375 | if (asoc->strreset_chunk) |
376 | sctp_chunk_free(asoc->strreset_chunk); | |
377 | ||
1da177e4 LT |
378 | /* Clean up the bound address list. */ |
379 | sctp_bind_addr_free(&asoc->base.bind_addr); | |
380 | ||
381 | /* Do we need to go through all of our timers and | |
382 | * delete them? To be safe we will try to delete all, but we | |
383 | * should be able to go through and make a guess based | |
384 | * on our state. | |
385 | */ | |
386 | for (i = SCTP_EVENT_TIMEOUT_NONE; i < SCTP_NUM_TIMEOUT_TYPES; ++i) { | |
25cc4ae9 | 387 | if (del_timer(&asoc->timers[i])) |
1da177e4 LT |
388 | sctp_association_put(asoc); |
389 | } | |
390 | ||
391 | /* Free peer's cached cookie. */ | |
a51482bd | 392 | kfree(asoc->peer.cookie); |
730fc3d0 VY |
393 | kfree(asoc->peer.peer_random); |
394 | kfree(asoc->peer.peer_chunks); | |
395 | kfree(asoc->peer.peer_hmacs); | |
1da177e4 LT |
396 | |
397 | /* Release the transport structures. */ | |
398 | list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) { | |
399 | transport = list_entry(pos, struct sctp_transport, transports); | |
45122ca2 | 400 | list_del_rcu(pos); |
4f008781 | 401 | sctp_unhash_transport(transport); |
1da177e4 LT |
402 | sctp_transport_free(transport); |
403 | } | |
404 | ||
3f7a87d2 FF |
405 | asoc->peer.transport_count = 0; |
406 | ||
a000c01e | 407 | sctp_asconf_queue_teardown(asoc); |
1da177e4 | 408 | |
8a07eb0a | 409 | /* Free pending address space being deleted */ |
7d37d0c1 | 410 | kfree(asoc->asconf_addr_del_pending); |
8a07eb0a | 411 | |
a29a5bd4 VY |
412 | /* AUTH - Free the endpoint shared keys */ |
413 | sctp_auth_destroy_keys(&asoc->endpoint_shared_keys); | |
414 | ||
415 | /* AUTH - Free the association shared key */ | |
416 | sctp_auth_key_put(asoc->asoc_shared_key); | |
417 | ||
1da177e4 LT |
418 | sctp_association_put(asoc); |
419 | } | |
420 | ||
421 | /* Cleanup and free up an association. */ | |
422 | static void sctp_association_destroy(struct sctp_association *asoc) | |
423 | { | |
bb33381d DB |
424 | if (unlikely(!asoc->base.dead)) { |
425 | WARN(1, "Attempt to destroy undead association %p!\n", asoc); | |
426 | return; | |
427 | } | |
1da177e4 LT |
428 | |
429 | sctp_endpoint_put(asoc->ep); | |
430 | sock_put(asoc->base.sk); | |
431 | ||
432 | if (asoc->assoc_id != 0) { | |
433 | spin_lock_bh(&sctp_assocs_id_lock); | |
434 | idr_remove(&sctp_assocs_id, asoc->assoc_id); | |
435 | spin_unlock_bh(&sctp_assocs_id_lock); | |
436 | } | |
437 | ||
547b792c | 438 | WARN_ON(atomic_read(&asoc->rmem_alloc)); |
049b3ff5 | 439 | |
fb6df5a6 | 440 | kfree_rcu(asoc, rcu); |
ff2266cd | 441 | SCTP_DBG_OBJCNT_DEC(assoc); |
1da177e4 LT |
442 | } |
443 | ||
444 | /* Change the primary destination address for the peer. */ | |
445 | void sctp_assoc_set_primary(struct sctp_association *asoc, | |
446 | struct sctp_transport *transport) | |
447 | { | |
319fa2a2 VY |
448 | int changeover = 0; |
449 | ||
450 | /* it's a changeover only if we already have a primary path | |
451 | * that we are changing | |
452 | */ | |
453 | if (asoc->peer.primary_path != NULL && | |
454 | asoc->peer.primary_path != transport) | |
455 | changeover = 1 ; | |
456 | ||
1da177e4 LT |
457 | asoc->peer.primary_path = transport; |
458 | ||
459 | /* Set a default msg_name for events. */ | |
460 | memcpy(&asoc->peer.primary_addr, &transport->ipaddr, | |
461 | sizeof(union sctp_addr)); | |
462 | ||
463 | /* If the primary path is changing, assume that the | |
464 | * user wants to use this new path. | |
465 | */ | |
ad8fec17 SS |
466 | if ((transport->state == SCTP_ACTIVE) || |
467 | (transport->state == SCTP_UNKNOWN)) | |
1da177e4 LT |
468 | asoc->peer.active_path = transport; |
469 | ||
470 | /* | |
471 | * SFR-CACC algorithm: | |
472 | * Upon the receipt of a request to change the primary | |
473 | * destination address, on the data structure for the new | |
474 | * primary destination, the sender MUST do the following: | |
475 | * | |
476 | * 1) If CHANGEOVER_ACTIVE is set, then there was a switch | |
477 | * to this destination address earlier. The sender MUST set | |
478 | * CYCLING_CHANGEOVER to indicate that this switch is a | |
479 | * double switch to the same destination address. | |
e0e9db17 VY |
480 | * |
481 | * Really, only bother is we have data queued or outstanding on | |
482 | * the association. | |
1da177e4 | 483 | */ |
e0e9db17 VY |
484 | if (!asoc->outqueue.outstanding_bytes && !asoc->outqueue.out_qlen) |
485 | return; | |
486 | ||
1da177e4 | 487 | if (transport->cacc.changeover_active) |
319fa2a2 | 488 | transport->cacc.cycling_changeover = changeover; |
1da177e4 LT |
489 | |
490 | /* 2) The sender MUST set CHANGEOVER_ACTIVE to indicate that | |
491 | * a changeover has occurred. | |
492 | */ | |
319fa2a2 | 493 | transport->cacc.changeover_active = changeover; |
1da177e4 LT |
494 | |
495 | /* 3) The sender MUST store the next TSN to be sent in | |
496 | * next_tsn_at_change. | |
497 | */ | |
498 | transport->cacc.next_tsn_at_change = asoc->next_tsn; | |
499 | } | |
500 | ||
3f7a87d2 FF |
501 | /* Remove a transport from an association. */ |
502 | void sctp_assoc_rm_peer(struct sctp_association *asoc, | |
503 | struct sctp_transport *peer) | |
504 | { | |
df132eff XL |
505 | struct sctp_transport *transport; |
506 | struct list_head *pos; | |
507 | struct sctp_chunk *ch; | |
3f7a87d2 | 508 | |
bb33381d DB |
509 | pr_debug("%s: association:%p addr:%pISpc\n", |
510 | __func__, asoc, &peer->ipaddr.sa); | |
3f7a87d2 FF |
511 | |
512 | /* If we are to remove the current retran_path, update it | |
513 | * to the next peer before removing this peer from the list. | |
514 | */ | |
515 | if (asoc->peer.retran_path == peer) | |
516 | sctp_assoc_update_retran_path(asoc); | |
517 | ||
518 | /* Remove this peer from the list. */ | |
45122ca2 | 519 | list_del_rcu(&peer->transports); |
4f008781 XL |
520 | /* Remove this peer from the transport hashtable */ |
521 | sctp_unhash_transport(peer); | |
3f7a87d2 FF |
522 | |
523 | /* Get the first transport of asoc. */ | |
524 | pos = asoc->peer.transport_addr_list.next; | |
525 | transport = list_entry(pos, struct sctp_transport, transports); | |
526 | ||
527 | /* Update any entries that match the peer to be deleted. */ | |
528 | if (asoc->peer.primary_path == peer) | |
529 | sctp_assoc_set_primary(asoc, transport); | |
530 | if (asoc->peer.active_path == peer) | |
531 | asoc->peer.active_path = transport; | |
9494c7c5 WY |
532 | if (asoc->peer.retran_path == peer) |
533 | asoc->peer.retran_path = transport; | |
3f7a87d2 FF |
534 | if (asoc->peer.last_data_from == peer) |
535 | asoc->peer.last_data_from = transport; | |
536 | ||
7b9438de XL |
537 | if (asoc->strreset_chunk && |
538 | asoc->strreset_chunk->transport == peer) { | |
539 | asoc->strreset_chunk->transport = transport; | |
540 | sctp_transport_reset_reconf_timer(transport); | |
541 | } | |
542 | ||
3f7a87d2 FF |
543 | /* If we remove the transport an INIT was last sent to, set it to |
544 | * NULL. Combined with the update of the retran path above, this | |
545 | * will cause the next INIT to be sent to the next available | |
546 | * transport, maintaining the cycle. | |
547 | */ | |
548 | if (asoc->init_last_sent_to == peer) | |
549 | asoc->init_last_sent_to = NULL; | |
550 | ||
6345b199 WY |
551 | /* If we remove the transport an SHUTDOWN was last sent to, set it |
552 | * to NULL. Combined with the update of the retran path above, this | |
553 | * will cause the next SHUTDOWN to be sent to the next available | |
554 | * transport, maintaining the cycle. | |
555 | */ | |
556 | if (asoc->shutdown_last_sent_to == peer) | |
557 | asoc->shutdown_last_sent_to = NULL; | |
558 | ||
10a43cea WY |
559 | /* If we remove the transport an ASCONF was last sent to, set it to |
560 | * NULL. | |
561 | */ | |
562 | if (asoc->addip_last_asconf && | |
563 | asoc->addip_last_asconf->transport == peer) | |
564 | asoc->addip_last_asconf->transport = NULL; | |
565 | ||
31b02e15 VY |
566 | /* If we have something on the transmitted list, we have to |
567 | * save it off. The best place is the active path. | |
568 | */ | |
569 | if (!list_empty(&peer->transmitted)) { | |
570 | struct sctp_transport *active = asoc->peer.active_path; | |
31b02e15 VY |
571 | |
572 | /* Reset the transport of each chunk on this list */ | |
573 | list_for_each_entry(ch, &peer->transmitted, | |
574 | transmitted_list) { | |
575 | ch->transport = NULL; | |
576 | ch->rtt_in_progress = 0; | |
577 | } | |
578 | ||
579 | list_splice_tail_init(&peer->transmitted, | |
580 | &active->transmitted); | |
581 | ||
582 | /* Start a T3 timer here in case it wasn't running so | |
583 | * that these migrated packets have a chance to get | |
2bccbadf | 584 | * retransmitted. |
31b02e15 VY |
585 | */ |
586 | if (!timer_pending(&active->T3_rtx_timer)) | |
587 | if (!mod_timer(&active->T3_rtx_timer, | |
588 | jiffies + active->rto)) | |
589 | sctp_transport_hold(active); | |
590 | } | |
591 | ||
df132eff XL |
592 | list_for_each_entry(ch, &asoc->outqueue.out_chunk_list, list) |
593 | if (ch->transport == peer) | |
594 | ch->transport = NULL; | |
595 | ||
3f7a87d2 FF |
596 | asoc->peer.transport_count--; |
597 | ||
598 | sctp_transport_free(peer); | |
599 | } | |
600 | ||
1da177e4 LT |
601 | /* Add a transport address to an association. */ |
602 | struct sctp_transport *sctp_assoc_add_peer(struct sctp_association *asoc, | |
603 | const union sctp_addr *addr, | |
dd0fc66f | 604 | const gfp_t gfp, |
3f7a87d2 | 605 | const int peer_state) |
1da177e4 | 606 | { |
89bf3450 | 607 | struct net *net = sock_net(asoc->base.sk); |
1da177e4 LT |
608 | struct sctp_transport *peer; |
609 | struct sctp_sock *sp; | |
610 | unsigned short port; | |
611 | ||
612 | sp = sctp_sk(asoc->base.sk); | |
613 | ||
614 | /* AF_INET and AF_INET6 share common port field. */ | |
4bdf4b5f | 615 | port = ntohs(addr->v4.sin_port); |
1da177e4 | 616 | |
bb33381d DB |
617 | pr_debug("%s: association:%p addr:%pISpc state:%d\n", __func__, |
618 | asoc, &addr->sa, peer_state); | |
3f7a87d2 | 619 | |
1da177e4 LT |
620 | /* Set the port if it has not been set yet. */ |
621 | if (0 == asoc->peer.port) | |
622 | asoc->peer.port = port; | |
623 | ||
624 | /* Check to see if this is a duplicate. */ | |
625 | peer = sctp_assoc_lookup_paddr(asoc, addr); | |
3f7a87d2 | 626 | if (peer) { |
add52379 VY |
627 | /* An UNKNOWN state is only set on transports added by |
628 | * user in sctp_connectx() call. Such transports should be | |
629 | * considered CONFIRMED per RFC 4960, Section 5.4. | |
630 | */ | |
ad8fec17 | 631 | if (peer->state == SCTP_UNKNOWN) { |
add52379 | 632 | peer->state = SCTP_ACTIVE; |
ad8fec17 | 633 | } |
1da177e4 | 634 | return peer; |
3f7a87d2 | 635 | } |
1da177e4 | 636 | |
89bf3450 | 637 | peer = sctp_transport_new(net, addr, gfp); |
1da177e4 LT |
638 | if (!peer) |
639 | return NULL; | |
640 | ||
641 | sctp_transport_set_owner(peer, asoc); | |
642 | ||
52ccb8e9 FF |
643 | /* Initialize the peer's heartbeat interval based on the |
644 | * association configured value. | |
645 | */ | |
646 | peer->hbinterval = asoc->hbinterval; | |
647 | ||
648 | /* Set the path max_retrans. */ | |
649 | peer->pathmaxrxt = asoc->pathmaxrxt; | |
650 | ||
2bccbadf | 651 | /* And the partial failure retrans threshold */ |
5aa93bcf NH |
652 | peer->pf_retrans = asoc->pf_retrans; |
653 | ||
52ccb8e9 FF |
654 | /* Initialize the peer's SACK delay timeout based on the |
655 | * association configured value. | |
656 | */ | |
657 | peer->sackdelay = asoc->sackdelay; | |
d364d927 | 658 | peer->sackfreq = asoc->sackfreq; |
52ccb8e9 | 659 | |
4be4139f XL |
660 | if (addr->sa.sa_family == AF_INET6) { |
661 | __be32 info = addr->v6.sin6_flowinfo; | |
662 | ||
663 | if (info) { | |
664 | peer->flowlabel = ntohl(info & IPV6_FLOWLABEL_MASK); | |
665 | peer->flowlabel |= SCTP_FLOWLABEL_SET_MASK; | |
666 | } else { | |
667 | peer->flowlabel = asoc->flowlabel; | |
668 | } | |
669 | } | |
8a9c58d2 XL |
670 | peer->dscp = asoc->dscp; |
671 | ||
52ccb8e9 FF |
672 | /* Enable/disable heartbeat, SACK delay, and path MTU discovery |
673 | * based on association setting. | |
674 | */ | |
675 | peer->param_flags = asoc->param_flags; | |
676 | ||
1da177e4 | 677 | /* Initialize the pmtu of the transport. */ |
800e00c1 | 678 | sctp_transport_route(peer, NULL, sp); |
1da177e4 LT |
679 | |
680 | /* If this is the first transport addr on this association, | |
681 | * initialize the association PMTU to the peer's PMTU. | |
682 | * If not and the current association PMTU is higher than the new | |
683 | * peer's PMTU, reset the association PMTU to the new peer's PMTU. | |
684 | */ | |
c4b2893d MRL |
685 | sctp_assoc_set_pmtu(asoc, asoc->pathmtu ? |
686 | min_t(int, peer->pathmtu, asoc->pathmtu) : | |
687 | peer->pathmtu); | |
bb33381d | 688 | |
6d0ccbac | 689 | peer->pmtu_pending = 0; |
1da177e4 | 690 | |
1da177e4 LT |
691 | /* The asoc->peer.port might not be meaningful yet, but |
692 | * initialize the packet structure anyway. | |
693 | */ | |
694 | sctp_packet_init(&peer->packet, peer, asoc->base.bind_addr.port, | |
695 | asoc->peer.port); | |
696 | ||
697 | /* 7.2.1 Slow-Start | |
698 | * | |
699 | * o The initial cwnd before DATA transmission or after a sufficiently | |
700 | * long idle period MUST be set to | |
701 | * min(4*MTU, max(2*MTU, 4380 bytes)) | |
702 | * | |
703 | * o The initial value of ssthresh MAY be arbitrarily high | |
704 | * (for example, implementations MAY use the size of the | |
705 | * receiver advertised window). | |
706 | */ | |
52ccb8e9 | 707 | peer->cwnd = min(4*asoc->pathmtu, max_t(__u32, 2*asoc->pathmtu, 4380)); |
1da177e4 LT |
708 | |
709 | /* At this point, we may not have the receiver's advertised window, | |
710 | * so initialize ssthresh to the default value and it will be set | |
711 | * later when we process the INIT. | |
712 | */ | |
713 | peer->ssthresh = SCTP_DEFAULT_MAXWINDOW; | |
714 | ||
715 | peer->partial_bytes_acked = 0; | |
716 | peer->flight_size = 0; | |
46d5a808 | 717 | peer->burst_limited = 0; |
1da177e4 | 718 | |
1da177e4 LT |
719 | /* Set the transport's RTO.initial value */ |
720 | peer->rto = asoc->rto_initial; | |
196d6759 | 721 | sctp_max_rto(asoc, peer); |
1da177e4 | 722 | |
3f7a87d2 FF |
723 | /* Set the peer's active state. */ |
724 | peer->state = peer_state; | |
725 | ||
7fda702f XL |
726 | /* Add this peer into the transport hashtable */ |
727 | if (sctp_hash_transport(peer)) { | |
728 | sctp_transport_free(peer); | |
729 | return NULL; | |
730 | } | |
731 | ||
1da177e4 | 732 | /* Attach the remote transport to our asoc. */ |
45122ca2 | 733 | list_add_tail_rcu(&peer->transports, &asoc->peer.transport_addr_list); |
3f7a87d2 | 734 | asoc->peer.transport_count++; |
1da177e4 LT |
735 | |
736 | /* If we do not yet have a primary path, set one. */ | |
737 | if (!asoc->peer.primary_path) { | |
738 | sctp_assoc_set_primary(asoc, peer); | |
739 | asoc->peer.retran_path = peer; | |
740 | } | |
741 | ||
fbdf501c VY |
742 | if (asoc->peer.active_path == asoc->peer.retran_path && |
743 | peer->state != SCTP_UNCONFIRMED) { | |
1da177e4 | 744 | asoc->peer.retran_path = peer; |
3f7a87d2 | 745 | } |
1da177e4 LT |
746 | |
747 | return peer; | |
748 | } | |
749 | ||
750 | /* Delete a transport address from an association. */ | |
751 | void sctp_assoc_del_peer(struct sctp_association *asoc, | |
752 | const union sctp_addr *addr) | |
753 | { | |
754 | struct list_head *pos; | |
755 | struct list_head *temp; | |
1da177e4 LT |
756 | struct sctp_transport *transport; |
757 | ||
758 | list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) { | |
759 | transport = list_entry(pos, struct sctp_transport, transports); | |
760 | if (sctp_cmp_addr_exact(addr, &transport->ipaddr)) { | |
3f7a87d2 FF |
761 | /* Do book keeping for removing the peer and free it. */ |
762 | sctp_assoc_rm_peer(asoc, transport); | |
1da177e4 LT |
763 | break; |
764 | } | |
765 | } | |
1da177e4 LT |
766 | } |
767 | ||
768 | /* Lookup a transport by address. */ | |
769 | struct sctp_transport *sctp_assoc_lookup_paddr( | |
770 | const struct sctp_association *asoc, | |
771 | const union sctp_addr *address) | |
772 | { | |
773 | struct sctp_transport *t; | |
1da177e4 LT |
774 | |
775 | /* Cycle through all transports searching for a peer address. */ | |
776 | ||
9dbc15f0 RD |
777 | list_for_each_entry(t, &asoc->peer.transport_addr_list, |
778 | transports) { | |
1da177e4 LT |
779 | if (sctp_cmp_addr_exact(address, &t->ipaddr)) |
780 | return t; | |
781 | } | |
782 | ||
783 | return NULL; | |
784 | } | |
785 | ||
42e30bf3 VY |
786 | /* Remove all transports except a give one */ |
787 | void sctp_assoc_del_nonprimary_peers(struct sctp_association *asoc, | |
788 | struct sctp_transport *primary) | |
789 | { | |
790 | struct sctp_transport *temp; | |
791 | struct sctp_transport *t; | |
792 | ||
793 | list_for_each_entry_safe(t, temp, &asoc->peer.transport_addr_list, | |
794 | transports) { | |
795 | /* if the current transport is not the primary one, delete it */ | |
796 | if (t != primary) | |
797 | sctp_assoc_rm_peer(asoc, t); | |
798 | } | |
42e30bf3 VY |
799 | } |
800 | ||
1da177e4 LT |
801 | /* Engage in transport control operations. |
802 | * Mark the transport up or down and send a notification to the user. | |
803 | * Select and update the new active and retran paths. | |
804 | */ | |
805 | void sctp_assoc_control_transport(struct sctp_association *asoc, | |
806 | struct sctp_transport *transport, | |
0ceaeebe | 807 | enum sctp_transport_cmd command, |
1da177e4 LT |
808 | sctp_sn_error_t error) |
809 | { | |
1da177e4 | 810 | struct sctp_ulpevent *event; |
0906e20f | 811 | struct sockaddr_storage addr; |
1da177e4 | 812 | int spc_state = 0; |
5aa93bcf | 813 | bool ulp_notify = true; |
1da177e4 LT |
814 | |
815 | /* Record the transition on the transport. */ | |
816 | switch (command) { | |
817 | case SCTP_TRANSPORT_UP: | |
1ae4114d VY |
818 | /* If we are moving from UNCONFIRMED state due |
819 | * to heartbeat success, report the SCTP_ADDR_CONFIRMED | |
820 | * state to the user, otherwise report SCTP_ADDR_AVAILABLE. | |
821 | */ | |
822 | if (SCTP_UNCONFIRMED == transport->state && | |
823 | SCTP_HEARTBEAT_SUCCESS == error) | |
824 | spc_state = SCTP_ADDR_CONFIRMED; | |
825 | else | |
826 | spc_state = SCTP_ADDR_AVAILABLE; | |
5aa93bcf | 827 | /* Don't inform ULP about transition from PF to |
ac4f9599 | 828 | * active state and set cwnd to 1 MTU, see SCTP |
5aa93bcf NH |
829 | * Quick failover draft section 5.1, point 5 |
830 | */ | |
831 | if (transport->state == SCTP_PF) { | |
832 | ulp_notify = false; | |
ac4f9599 | 833 | transport->cwnd = asoc->pathmtu; |
5aa93bcf | 834 | } |
3f7a87d2 | 835 | transport->state = SCTP_ACTIVE; |
1da177e4 LT |
836 | break; |
837 | ||
838 | case SCTP_TRANSPORT_DOWN: | |
40187886 VY |
839 | /* If the transport was never confirmed, do not transition it |
840 | * to inactive state. Also, release the cached route since | |
841 | * there may be a better route next time. | |
cc75689a VY |
842 | */ |
843 | if (transport->state != SCTP_UNCONFIRMED) | |
844 | transport->state = SCTP_INACTIVE; | |
40187886 | 845 | else { |
c86a773c | 846 | sctp_transport_dst_release(transport); |
061079ac | 847 | ulp_notify = false; |
40187886 | 848 | } |
cc75689a | 849 | |
1da177e4 LT |
850 | spc_state = SCTP_ADDR_UNREACHABLE; |
851 | break; | |
852 | ||
5aa93bcf NH |
853 | case SCTP_TRANSPORT_PF: |
854 | transport->state = SCTP_PF; | |
855 | ulp_notify = false; | |
856 | break; | |
857 | ||
1da177e4 LT |
858 | default: |
859 | return; | |
3ff50b79 | 860 | } |
1da177e4 | 861 | |
b82e8f31 DB |
862 | /* Generate and send a SCTP_PEER_ADDR_CHANGE notification |
863 | * to the user. | |
1da177e4 | 864 | */ |
5aa93bcf NH |
865 | if (ulp_notify) { |
866 | memset(&addr, 0, sizeof(struct sockaddr_storage)); | |
867 | memcpy(&addr, &transport->ipaddr, | |
868 | transport->af_specific->sockaddr_len); | |
b82e8f31 | 869 | |
5aa93bcf NH |
870 | event = sctp_ulpevent_make_peer_addr_change(asoc, &addr, |
871 | 0, spc_state, error, GFP_ATOMIC); | |
872 | if (event) | |
9162e0ed | 873 | asoc->stream.si->enqueue_event(&asoc->ulpq, event); |
5aa93bcf | 874 | } |
1da177e4 LT |
875 | |
876 | /* Select new active and retran paths. */ | |
b82e8f31 | 877 | sctp_select_active_and_retran_path(asoc); |
1da177e4 LT |
878 | } |
879 | ||
880 | /* Hold a reference to an association. */ | |
881 | void sctp_association_hold(struct sctp_association *asoc) | |
882 | { | |
c638457a | 883 | refcount_inc(&asoc->base.refcnt); |
1da177e4 LT |
884 | } |
885 | ||
886 | /* Release a reference to an association and cleanup | |
887 | * if there are no more references. | |
888 | */ | |
889 | void sctp_association_put(struct sctp_association *asoc) | |
890 | { | |
c638457a | 891 | if (refcount_dec_and_test(&asoc->base.refcnt)) |
1da177e4 LT |
892 | sctp_association_destroy(asoc); |
893 | } | |
894 | ||
895 | /* Allocate the next TSN, Transmission Sequence Number, for the given | |
896 | * association. | |
897 | */ | |
898 | __u32 sctp_association_get_next_tsn(struct sctp_association *asoc) | |
899 | { | |
900 | /* From Section 1.6 Serial Number Arithmetic: | |
901 | * Transmission Sequence Numbers wrap around when they reach | |
902 | * 2**32 - 1. That is, the next TSN a DATA chunk MUST use | |
903 | * after transmitting TSN = 2*32 - 1 is TSN = 0. | |
904 | */ | |
905 | __u32 retval = asoc->next_tsn; | |
906 | asoc->next_tsn++; | |
907 | asoc->unack_data++; | |
908 | ||
909 | return retval; | |
910 | } | |
911 | ||
912 | /* Compare two addresses to see if they match. Wildcard addresses | |
913 | * only match themselves. | |
914 | */ | |
915 | int sctp_cmp_addr_exact(const union sctp_addr *ss1, | |
916 | const union sctp_addr *ss2) | |
917 | { | |
918 | struct sctp_af *af; | |
919 | ||
920 | af = sctp_get_af_specific(ss1->sa.sa_family); | |
921 | if (unlikely(!af)) | |
922 | return 0; | |
923 | ||
924 | return af->cmp_addr(ss1, ss2); | |
925 | } | |
926 | ||
927 | /* Return an ecne chunk to get prepended to a packet. | |
928 | * Note: We are sly and return a shared, prealloced chunk. FIXME: | |
929 | * No we don't, but we could/should. | |
930 | */ | |
931 | struct sctp_chunk *sctp_get_ecne_prepend(struct sctp_association *asoc) | |
932 | { | |
8b7318d3 | 933 | if (!asoc->need_ecne) |
934 | return NULL; | |
1da177e4 LT |
935 | |
936 | /* Send ECNE if needed. | |
937 | * Not being able to allocate a chunk here is not deadly. | |
938 | */ | |
8b7318d3 | 939 | return sctp_make_ecne(asoc, asoc->last_ecne_tsn); |
1da177e4 LT |
940 | } |
941 | ||
942 | /* | |
943 | * Find which transport this TSN was sent on. | |
944 | */ | |
945 | struct sctp_transport *sctp_assoc_lookup_tsn(struct sctp_association *asoc, | |
946 | __u32 tsn) | |
947 | { | |
948 | struct sctp_transport *active; | |
949 | struct sctp_transport *match; | |
1da177e4 LT |
950 | struct sctp_transport *transport; |
951 | struct sctp_chunk *chunk; | |
dbc16db1 | 952 | __be32 key = htonl(tsn); |
1da177e4 LT |
953 | |
954 | match = NULL; | |
955 | ||
956 | /* | |
957 | * FIXME: In general, find a more efficient data structure for | |
958 | * searching. | |
959 | */ | |
960 | ||
961 | /* | |
962 | * The general strategy is to search each transport's transmitted | |
963 | * list. Return which transport this TSN lives on. | |
964 | * | |
965 | * Let's be hopeful and check the active_path first. | |
966 | * Another optimization would be to know if there is only one | |
967 | * outbound path and not have to look for the TSN at all. | |
968 | * | |
969 | */ | |
970 | ||
971 | active = asoc->peer.active_path; | |
972 | ||
9dbc15f0 RD |
973 | list_for_each_entry(chunk, &active->transmitted, |
974 | transmitted_list) { | |
1da177e4 LT |
975 | |
976 | if (key == chunk->subh.data_hdr->tsn) { | |
977 | match = active; | |
978 | goto out; | |
979 | } | |
980 | } | |
981 | ||
982 | /* If not found, go search all the other transports. */ | |
9dbc15f0 RD |
983 | list_for_each_entry(transport, &asoc->peer.transport_addr_list, |
984 | transports) { | |
1da177e4 LT |
985 | |
986 | if (transport == active) | |
2317f449 | 987 | continue; |
9dbc15f0 RD |
988 | list_for_each_entry(chunk, &transport->transmitted, |
989 | transmitted_list) { | |
1da177e4 LT |
990 | if (key == chunk->subh.data_hdr->tsn) { |
991 | match = transport; | |
992 | goto out; | |
993 | } | |
994 | } | |
995 | } | |
996 | out: | |
997 | return match; | |
998 | } | |
999 | ||
1da177e4 | 1000 | /* Do delayed input processing. This is scheduled by sctp_rcv(). */ |
c4028958 | 1001 | static void sctp_assoc_bh_rcv(struct work_struct *work) |
1da177e4 | 1002 | { |
c4028958 DH |
1003 | struct sctp_association *asoc = |
1004 | container_of(work, struct sctp_association, | |
1005 | base.inqueue.immediate); | |
55e26eb9 | 1006 | struct net *net = sock_net(asoc->base.sk); |
bfc6f827 | 1007 | union sctp_subtype subtype; |
1da177e4 LT |
1008 | struct sctp_endpoint *ep; |
1009 | struct sctp_chunk *chunk; | |
1da177e4 | 1010 | struct sctp_inq *inqueue; |
59d8d443 | 1011 | int first_time = 1; /* is this the first time through the loop */ |
1da177e4 | 1012 | int error = 0; |
59d8d443 | 1013 | int state; |
1da177e4 LT |
1014 | |
1015 | /* The association should be held so we should be safe. */ | |
1016 | ep = asoc->ep; | |
1da177e4 LT |
1017 | |
1018 | inqueue = &asoc->base.inqueue; | |
1019 | sctp_association_hold(asoc); | |
1020 | while (NULL != (chunk = sctp_inq_pop(inqueue))) { | |
1021 | state = asoc->state; | |
1022 | subtype = SCTP_ST_CHUNK(chunk->chunk_hdr->type); | |
1023 | ||
59d8d443 XL |
1024 | /* If the first chunk in the packet is AUTH, do special |
1025 | * processing specified in Section 6.3 of SCTP-AUTH spec | |
1026 | */ | |
1027 | if (first_time && subtype.chunk == SCTP_CID_AUTH) { | |
1028 | struct sctp_chunkhdr *next_hdr; | |
1029 | ||
1030 | next_hdr = sctp_inq_peek(inqueue); | |
1031 | if (!next_hdr) | |
1032 | goto normal; | |
1033 | ||
1034 | /* If the next chunk is COOKIE-ECHO, skip the AUTH | |
1035 | * chunk while saving a pointer to it so we can do | |
1036 | * Authentication later (during cookie-echo | |
1037 | * processing). | |
1038 | */ | |
1039 | if (next_hdr->type == SCTP_CID_COOKIE_ECHO) { | |
1040 | chunk->auth_chunk = skb_clone(chunk->skb, | |
1041 | GFP_ATOMIC); | |
1042 | chunk->auth = 1; | |
1043 | continue; | |
1044 | } | |
1045 | } | |
1046 | ||
1047 | normal: | |
bbd0d598 VY |
1048 | /* SCTP-AUTH, Section 6.3: |
1049 | * The receiver has a list of chunk types which it expects | |
1050 | * to be received only after an AUTH-chunk. This list has | |
1051 | * been sent to the peer during the association setup. It | |
1052 | * MUST silently discard these chunks if they are not placed | |
1053 | * after an AUTH chunk in the packet. | |
1054 | */ | |
1055 | if (sctp_auth_recv_cid(subtype.chunk, asoc) && !chunk->auth) | |
1056 | continue; | |
1057 | ||
1da177e4 LT |
1058 | /* Remember where the last DATA chunk came from so we |
1059 | * know where to send the SACK. | |
1060 | */ | |
1061 | if (sctp_chunk_is_data(chunk)) | |
1062 | asoc->peer.last_data_from = chunk->transport; | |
196d6759 | 1063 | else { |
55e26eb9 | 1064 | SCTP_INC_STATS(net, SCTP_MIB_INCTRLCHUNKS); |
196d6759 MB |
1065 | asoc->stats.ictrlchunks++; |
1066 | if (chunk->chunk_hdr->type == SCTP_CID_SACK) | |
1067 | asoc->stats.isacks++; | |
1068 | } | |
1da177e4 LT |
1069 | |
1070 | if (chunk->transport) | |
e575235f | 1071 | chunk->transport->last_time_heard = ktime_get(); |
1da177e4 LT |
1072 | |
1073 | /* Run through the state machine. */ | |
55e26eb9 | 1074 | error = sctp_do_sm(net, SCTP_EVENT_T_CHUNK, subtype, |
1da177e4 LT |
1075 | state, ep, asoc, chunk, GFP_ATOMIC); |
1076 | ||
1077 | /* Check to see if the association is freed in response to | |
1078 | * the incoming chunk. If so, get out of the while loop. | |
1079 | */ | |
1080 | if (asoc->base.dead) | |
1081 | break; | |
1082 | ||
1083 | /* If there is an error on chunk, discard this packet. */ | |
1084 | if (error && chunk) | |
1085 | chunk->pdiscard = 1; | |
59d8d443 XL |
1086 | |
1087 | if (first_time) | |
1088 | first_time = 0; | |
1da177e4 LT |
1089 | } |
1090 | sctp_association_put(asoc); | |
1091 | } | |
1092 | ||
1093 | /* This routine moves an association from its old sk to a new sk. */ | |
1094 | void sctp_assoc_migrate(struct sctp_association *assoc, struct sock *newsk) | |
1095 | { | |
1096 | struct sctp_sock *newsp = sctp_sk(newsk); | |
1097 | struct sock *oldsk = assoc->base.sk; | |
1098 | ||
1099 | /* Delete the association from the old endpoint's list of | |
1100 | * associations. | |
1101 | */ | |
1102 | list_del_init(&assoc->asocs); | |
1103 | ||
1104 | /* Decrement the backlog value for a TCP-style socket. */ | |
1105 | if (sctp_style(oldsk, TCP)) | |
1106 | oldsk->sk_ack_backlog--; | |
1107 | ||
1108 | /* Release references to the old endpoint and the sock. */ | |
1109 | sctp_endpoint_put(assoc->ep); | |
1110 | sock_put(assoc->base.sk); | |
1111 | ||
1112 | /* Get a reference to the new endpoint. */ | |
1113 | assoc->ep = newsp->ep; | |
1114 | sctp_endpoint_hold(assoc->ep); | |
1115 | ||
1116 | /* Get a reference to the new sock. */ | |
1117 | assoc->base.sk = newsk; | |
1118 | sock_hold(assoc->base.sk); | |
1119 | ||
1120 | /* Add the association to the new endpoint's list of associations. */ | |
1121 | sctp_endpoint_add_asoc(newsp->ep, assoc); | |
1122 | } | |
1123 | ||
1124 | /* Update an association (possibly from unexpected COOKIE-ECHO processing). */ | |
5ee8aa68 XL |
1125 | int sctp_assoc_update(struct sctp_association *asoc, |
1126 | struct sctp_association *new) | |
1da177e4 LT |
1127 | { |
1128 | struct sctp_transport *trans; | |
1129 | struct list_head *pos, *temp; | |
1130 | ||
1131 | /* Copy in new parameters of peer. */ | |
1132 | asoc->c = new->c; | |
1133 | asoc->peer.rwnd = new->peer.rwnd; | |
1134 | asoc->peer.sack_needed = new->peer.sack_needed; | |
1be9a950 | 1135 | asoc->peer.auth_capable = new->peer.auth_capable; |
1da177e4 | 1136 | asoc->peer.i = new->peer.i; |
5ee8aa68 XL |
1137 | |
1138 | if (!sctp_tsnmap_init(&asoc->peer.tsn_map, SCTP_TSN_MAP_INITIAL, | |
1139 | asoc->peer.i.initial_tsn, GFP_ATOMIC)) | |
1140 | return -ENOMEM; | |
1da177e4 LT |
1141 | |
1142 | /* Remove any peer addresses not present in the new association. */ | |
1143 | list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) { | |
1144 | trans = list_entry(pos, struct sctp_transport, transports); | |
0c42749c VY |
1145 | if (!sctp_assoc_lookup_paddr(new, &trans->ipaddr)) { |
1146 | sctp_assoc_rm_peer(asoc, trans); | |
1147 | continue; | |
1148 | } | |
749bf921 VY |
1149 | |
1150 | if (asoc->state >= SCTP_STATE_ESTABLISHED) | |
1151 | sctp_transport_reset(trans); | |
1da177e4 LT |
1152 | } |
1153 | ||
1154 | /* If the case is A (association restart), use | |
1155 | * initial_tsn as next_tsn. If the case is B, use | |
1156 | * current next_tsn in case data sent to peer | |
1157 | * has been discarded and needs retransmission. | |
1158 | */ | |
1159 | if (asoc->state >= SCTP_STATE_ESTABLISHED) { | |
1160 | asoc->next_tsn = new->next_tsn; | |
1161 | asoc->ctsn_ack_point = new->ctsn_ack_point; | |
1162 | asoc->adv_peer_ack_point = new->adv_peer_ack_point; | |
1163 | ||
1164 | /* Reinitialize SSN for both local streams | |
1165 | * and peer's streams. | |
1166 | */ | |
cee360ab | 1167 | sctp_stream_clear(&asoc->stream); |
1da177e4 | 1168 | |
0b58a811 VY |
1169 | /* Flush the ULP reassembly and ordered queue. |
1170 | * Any data there will now be stale and will | |
1171 | * cause problems. | |
1172 | */ | |
1173 | sctp_ulpq_flush(&asoc->ulpq); | |
1174 | ||
749bf921 VY |
1175 | /* reset the overall association error count so |
1176 | * that the restarted association doesn't get torn | |
1177 | * down on the next retransmission timer. | |
1178 | */ | |
1179 | asoc->overall_error_count = 0; | |
1180 | ||
1da177e4 LT |
1181 | } else { |
1182 | /* Add any peer addresses from the new association. */ | |
9dbc15f0 | 1183 | list_for_each_entry(trans, &new->peer.transport_addr_list, |
5ee8aa68 XL |
1184 | transports) |
1185 | if (!sctp_assoc_lookup_paddr(asoc, &trans->ipaddr) && | |
1186 | !sctp_assoc_add_peer(asoc, &trans->ipaddr, | |
1187 | GFP_ATOMIC, trans->state)) | |
1188 | return -ENOMEM; | |
1da177e4 LT |
1189 | |
1190 | asoc->ctsn_ack_point = asoc->next_tsn - 1; | |
1191 | asoc->adv_peer_ack_point = asoc->ctsn_ack_point; | |
3ab21379 | 1192 | |
cee360ab XL |
1193 | if (sctp_state(asoc, COOKIE_WAIT)) |
1194 | sctp_stream_update(&asoc->stream, &new->stream); | |
07d93967 | 1195 | |
4abf5a65 | 1196 | /* get a new assoc id if we don't have one yet. */ |
5ee8aa68 XL |
1197 | if (sctp_assoc_set_id(asoc, GFP_ATOMIC)) |
1198 | return -ENOMEM; | |
1da177e4 | 1199 | } |
a29a5bd4 | 1200 | |
9d2c881a | 1201 | /* SCTP-AUTH: Save the peer parameters from the new associations |
730fc3d0 VY |
1202 | * and also move the association shared keys over |
1203 | */ | |
1204 | kfree(asoc->peer.peer_random); | |
1205 | asoc->peer.peer_random = new->peer.peer_random; | |
1206 | new->peer.peer_random = NULL; | |
1207 | ||
1208 | kfree(asoc->peer.peer_chunks); | |
1209 | asoc->peer.peer_chunks = new->peer.peer_chunks; | |
1210 | new->peer.peer_chunks = NULL; | |
1211 | ||
1212 | kfree(asoc->peer.peer_hmacs); | |
1213 | asoc->peer.peer_hmacs = new->peer.peer_hmacs; | |
1214 | new->peer.peer_hmacs = NULL; | |
1215 | ||
5ee8aa68 | 1216 | return sctp_auth_asoc_init_active_key(asoc, GFP_ATOMIC); |
1da177e4 LT |
1217 | } |
1218 | ||
1219 | /* Update the retran path for sending a retransmitted packet. | |
4c47af4d DB |
1220 | * See also RFC4960, 6.4. Multi-Homed SCTP Endpoints: |
1221 | * | |
1222 | * When there is outbound data to send and the primary path | |
1223 | * becomes inactive (e.g., due to failures), or where the | |
1224 | * SCTP user explicitly requests to send data to an | |
1225 | * inactive destination transport address, before reporting | |
1226 | * an error to its ULP, the SCTP endpoint should try to send | |
1227 | * the data to an alternate active destination transport | |
1228 | * address if one exists. | |
1229 | * | |
1230 | * When retransmitting data that timed out, if the endpoint | |
1231 | * is multihomed, it should consider each source-destination | |
1232 | * address pair in its retransmission selection policy. | |
1233 | * When retransmitting timed-out data, the endpoint should | |
1234 | * attempt to pick the most divergent source-destination | |
1235 | * pair from the original source-destination pair to which | |
1236 | * the packet was transmitted. | |
1237 | * | |
1238 | * Note: Rules for picking the most divergent source-destination | |
1239 | * pair are an implementation decision and are not specified | |
1240 | * within this document. | |
1241 | * | |
1242 | * Our basic strategy is to round-robin transports in priorities | |
2103d6b8 | 1243 | * according to sctp_trans_score() e.g., if no such |
4c47af4d DB |
1244 | * transport with state SCTP_ACTIVE exists, round-robin through |
1245 | * SCTP_UNKNOWN, etc. You get the picture. | |
1da177e4 | 1246 | */ |
4c47af4d | 1247 | static u8 sctp_trans_score(const struct sctp_transport *trans) |
1da177e4 | 1248 | { |
2103d6b8 DV |
1249 | switch (trans->state) { |
1250 | case SCTP_ACTIVE: | |
1251 | return 3; /* best case */ | |
1252 | case SCTP_UNKNOWN: | |
1253 | return 2; | |
1254 | case SCTP_PF: | |
1255 | return 1; | |
1256 | default: /* case SCTP_INACTIVE */ | |
1257 | return 0; /* worst case */ | |
1258 | } | |
4c47af4d | 1259 | } |
1da177e4 | 1260 | |
a7288c4d DB |
1261 | static struct sctp_transport *sctp_trans_elect_tie(struct sctp_transport *trans1, |
1262 | struct sctp_transport *trans2) | |
1263 | { | |
1264 | if (trans1->error_count > trans2->error_count) { | |
1265 | return trans2; | |
1266 | } else if (trans1->error_count == trans2->error_count && | |
1267 | ktime_after(trans2->last_time_heard, | |
1268 | trans1->last_time_heard)) { | |
1269 | return trans2; | |
1270 | } else { | |
1271 | return trans1; | |
1272 | } | |
1273 | } | |
1274 | ||
4c47af4d DB |
1275 | static struct sctp_transport *sctp_trans_elect_best(struct sctp_transport *curr, |
1276 | struct sctp_transport *best) | |
1277 | { | |
a7288c4d DB |
1278 | u8 score_curr, score_best; |
1279 | ||
ea4f19c1 | 1280 | if (best == NULL || curr == best) |
4c47af4d | 1281 | return curr; |
4141ddc0 | 1282 | |
a7288c4d DB |
1283 | score_curr = sctp_trans_score(curr); |
1284 | score_best = sctp_trans_score(best); | |
1285 | ||
1286 | /* First, try a score-based selection if both transport states | |
1287 | * differ. If we're in a tie, lets try to make a more clever | |
1288 | * decision here based on error counts and last time heard. | |
1289 | */ | |
1290 | if (score_curr > score_best) | |
1291 | return curr; | |
1292 | else if (score_curr == score_best) | |
39d2adeb | 1293 | return sctp_trans_elect_tie(best, curr); |
a7288c4d DB |
1294 | else |
1295 | return best; | |
4c47af4d | 1296 | } |
1da177e4 | 1297 | |
4c47af4d DB |
1298 | void sctp_assoc_update_retran_path(struct sctp_association *asoc) |
1299 | { | |
1300 | struct sctp_transport *trans = asoc->peer.retran_path; | |
1301 | struct sctp_transport *trans_next = NULL; | |
1da177e4 | 1302 | |
4c47af4d DB |
1303 | /* We're done as we only have the one and only path. */ |
1304 | if (asoc->peer.transport_count == 1) | |
1305 | return; | |
1306 | /* If active_path and retran_path are the same and active, | |
1307 | * then this is the only active path. Use it. | |
1308 | */ | |
1309 | if (asoc->peer.active_path == asoc->peer.retran_path && | |
1310 | asoc->peer.active_path->state == SCTP_ACTIVE) | |
1311 | return; | |
1da177e4 | 1312 | |
4c47af4d DB |
1313 | /* Iterate from retran_path's successor back to retran_path. */ |
1314 | for (trans = list_next_entry(trans, transports); 1; | |
1315 | trans = list_next_entry(trans, transports)) { | |
1316 | /* Manually skip the head element. */ | |
1317 | if (&trans->transports == &asoc->peer.transport_addr_list) | |
1318 | continue; | |
1319 | if (trans->state == SCTP_UNCONFIRMED) | |
1320 | continue; | |
1321 | trans_next = sctp_trans_elect_best(trans, trans_next); | |
1322 | /* Active is good enough for immediate return. */ | |
1323 | if (trans_next->state == SCTP_ACTIVE) | |
4141ddc0 | 1324 | break; |
4c47af4d DB |
1325 | /* We've reached the end, time to update path. */ |
1326 | if (trans == asoc->peer.retran_path) | |
1da177e4 | 1327 | break; |
1da177e4 LT |
1328 | } |
1329 | ||
433131ba | 1330 | asoc->peer.retran_path = trans_next; |
3f7a87d2 | 1331 | |
4c47af4d DB |
1332 | pr_debug("%s: association:%p updated new path to addr:%pISpc\n", |
1333 | __func__, asoc, &asoc->peer.retran_path->ipaddr.sa); | |
3f7a87d2 FF |
1334 | } |
1335 | ||
b82e8f31 DB |
1336 | static void sctp_select_active_and_retran_path(struct sctp_association *asoc) |
1337 | { | |
1338 | struct sctp_transport *trans, *trans_pri = NULL, *trans_sec = NULL; | |
a7288c4d | 1339 | struct sctp_transport *trans_pf = NULL; |
b82e8f31 DB |
1340 | |
1341 | /* Look for the two most recently used active transports. */ | |
1342 | list_for_each_entry(trans, &asoc->peer.transport_addr_list, | |
1343 | transports) { | |
a7288c4d | 1344 | /* Skip uninteresting transports. */ |
b82e8f31 | 1345 | if (trans->state == SCTP_INACTIVE || |
a7288c4d | 1346 | trans->state == SCTP_UNCONFIRMED) |
b82e8f31 | 1347 | continue; |
a7288c4d DB |
1348 | /* Keep track of the best PF transport from our |
1349 | * list in case we don't find an active one. | |
1350 | */ | |
1351 | if (trans->state == SCTP_PF) { | |
1352 | trans_pf = sctp_trans_elect_best(trans, trans_pf); | |
1353 | continue; | |
1354 | } | |
1355 | /* For active transports, pick the most recent ones. */ | |
b82e8f31 | 1356 | if (trans_pri == NULL || |
e575235f DB |
1357 | ktime_after(trans->last_time_heard, |
1358 | trans_pri->last_time_heard)) { | |
b82e8f31 DB |
1359 | trans_sec = trans_pri; |
1360 | trans_pri = trans; | |
1361 | } else if (trans_sec == NULL || | |
e575235f DB |
1362 | ktime_after(trans->last_time_heard, |
1363 | trans_sec->last_time_heard)) { | |
b82e8f31 DB |
1364 | trans_sec = trans; |
1365 | } | |
1366 | } | |
1367 | ||
1368 | /* RFC 2960 6.4 Multi-Homed SCTP Endpoints | |
1369 | * | |
1370 | * By default, an endpoint should always transmit to the primary | |
1371 | * path, unless the SCTP user explicitly specifies the | |
1372 | * destination transport address (and possibly source transport | |
1373 | * address) to use. [If the primary is active but not most recent, | |
1374 | * bump the most recently used transport.] | |
1375 | */ | |
1376 | if ((asoc->peer.primary_path->state == SCTP_ACTIVE || | |
1377 | asoc->peer.primary_path->state == SCTP_UNKNOWN) && | |
1378 | asoc->peer.primary_path != trans_pri) { | |
1379 | trans_sec = trans_pri; | |
1380 | trans_pri = asoc->peer.primary_path; | |
1381 | } | |
1382 | ||
1383 | /* We did not find anything useful for a possible retransmission | |
1384 | * path; either primary path that we found is the the same as | |
1385 | * the current one, or we didn't generally find an active one. | |
1386 | */ | |
1387 | if (trans_sec == NULL) | |
1388 | trans_sec = trans_pri; | |
1389 | ||
1390 | /* If we failed to find a usable transport, just camp on the | |
aa4a83ee | 1391 | * active or pick a PF iff it's the better choice. |
b82e8f31 DB |
1392 | */ |
1393 | if (trans_pri == NULL) { | |
aa4a83ee DB |
1394 | trans_pri = sctp_trans_elect_best(asoc->peer.active_path, trans_pf); |
1395 | trans_sec = trans_pri; | |
b82e8f31 DB |
1396 | } |
1397 | ||
1398 | /* Set the active and retran transports. */ | |
1399 | asoc->peer.active_path = trans_pri; | |
1400 | asoc->peer.retran_path = trans_sec; | |
1401 | } | |
1402 | ||
4c47af4d DB |
1403 | struct sctp_transport * |
1404 | sctp_assoc_choose_alter_transport(struct sctp_association *asoc, | |
1405 | struct sctp_transport *last_sent_to) | |
3f7a87d2 | 1406 | { |
9919b455 WY |
1407 | /* If this is the first time packet is sent, use the active path, |
1408 | * else use the retran path. If the last packet was sent over the | |
3f7a87d2 FF |
1409 | * retran path, update the retran path and use it. |
1410 | */ | |
4c47af4d | 1411 | if (last_sent_to == NULL) { |
1da177e4 | 1412 | return asoc->peer.active_path; |
4c47af4d | 1413 | } else { |
9919b455 | 1414 | if (last_sent_to == asoc->peer.retran_path) |
1da177e4 | 1415 | sctp_assoc_update_retran_path(asoc); |
4c47af4d | 1416 | |
1da177e4 LT |
1417 | return asoc->peer.retran_path; |
1418 | } | |
1da177e4 LT |
1419 | } |
1420 | ||
2f5e3c9d MRL |
1421 | void sctp_assoc_update_frag_point(struct sctp_association *asoc) |
1422 | { | |
1423 | int frag = sctp_mtu_payload(sctp_sk(asoc->base.sk), asoc->pathmtu, | |
1424 | sctp_datachk_len(&asoc->stream)); | |
1425 | ||
1426 | if (asoc->user_frag) | |
1427 | frag = min_t(int, frag, asoc->user_frag); | |
1428 | ||
1429 | frag = min_t(int, frag, SCTP_MAX_CHUNK_LEN - | |
1430 | sctp_datachk_len(&asoc->stream)); | |
1431 | ||
1432 | asoc->frag_point = SCTP_TRUNC4(frag); | |
1433 | } | |
1434 | ||
c4b2893d MRL |
1435 | void sctp_assoc_set_pmtu(struct sctp_association *asoc, __u32 pmtu) |
1436 | { | |
2f5e3c9d | 1437 | if (asoc->pathmtu != pmtu) { |
c4b2893d | 1438 | asoc->pathmtu = pmtu; |
2f5e3c9d MRL |
1439 | sctp_assoc_update_frag_point(asoc); |
1440 | } | |
c4b2893d MRL |
1441 | |
1442 | pr_debug("%s: asoc:%p, pmtu:%d, frag_point:%d\n", __func__, asoc, | |
1443 | asoc->pathmtu, asoc->frag_point); | |
1444 | } | |
1445 | ||
1da177e4 LT |
1446 | /* Update the association's pmtu and frag_point by going through all the |
1447 | * transports. This routine is called when a transport's PMTU has changed. | |
1448 | */ | |
3ebfdf08 | 1449 | void sctp_assoc_sync_pmtu(struct sctp_association *asoc) |
1da177e4 LT |
1450 | { |
1451 | struct sctp_transport *t; | |
1da177e4 LT |
1452 | __u32 pmtu = 0; |
1453 | ||
1454 | if (!asoc) | |
1455 | return; | |
1456 | ||
1457 | /* Get the lowest pmtu of all the transports. */ | |
6ff0f871 | 1458 | list_for_each_entry(t, &asoc->peer.transport_addr_list, transports) { |
8a479491 | 1459 | if (t->pmtu_pending && t->dst) { |
d805397c XL |
1460 | sctp_transport_update_pmtu(t, |
1461 | atomic_read(&t->mtu_info)); | |
8a479491 VY |
1462 | t->pmtu_pending = 0; |
1463 | } | |
52ccb8e9 FF |
1464 | if (!pmtu || (t->pathmtu < pmtu)) |
1465 | pmtu = t->pathmtu; | |
1da177e4 LT |
1466 | } |
1467 | ||
c4b2893d | 1468 | sctp_assoc_set_pmtu(asoc, pmtu); |
1da177e4 LT |
1469 | } |
1470 | ||
1471 | /* Should we send a SACK to update our peer? */ | |
ce4a03db | 1472 | static inline bool sctp_peer_needs_update(struct sctp_association *asoc) |
1da177e4 | 1473 | { |
e1fc3b14 | 1474 | struct net *net = sock_net(asoc->base.sk); |
1da177e4 LT |
1475 | switch (asoc->state) { |
1476 | case SCTP_STATE_ESTABLISHED: | |
1477 | case SCTP_STATE_SHUTDOWN_PENDING: | |
1478 | case SCTP_STATE_SHUTDOWN_RECEIVED: | |
1479 | case SCTP_STATE_SHUTDOWN_SENT: | |
1480 | if ((asoc->rwnd > asoc->a_rwnd) && | |
90f2f531 | 1481 | ((asoc->rwnd - asoc->a_rwnd) >= max_t(__u32, |
e1fc3b14 | 1482 | (asoc->base.sk->sk_rcvbuf >> net->sctp.rwnd_upd_shift), |
90f2f531 | 1483 | asoc->pathmtu))) |
ce4a03db | 1484 | return true; |
1da177e4 LT |
1485 | break; |
1486 | default: | |
1487 | break; | |
1488 | } | |
ce4a03db | 1489 | return false; |
1da177e4 LT |
1490 | } |
1491 | ||
362d5204 DB |
1492 | /* Increase asoc's rwnd by len and send any window update SACK if needed. */ |
1493 | void sctp_assoc_rwnd_increase(struct sctp_association *asoc, unsigned int len) | |
1da177e4 LT |
1494 | { |
1495 | struct sctp_chunk *sack; | |
1496 | struct timer_list *timer; | |
1497 | ||
362d5204 DB |
1498 | if (asoc->rwnd_over) { |
1499 | if (asoc->rwnd_over >= len) { | |
1500 | asoc->rwnd_over -= len; | |
1501 | } else { | |
1502 | asoc->rwnd += (len - asoc->rwnd_over); | |
1503 | asoc->rwnd_over = 0; | |
1504 | } | |
1505 | } else { | |
1506 | asoc->rwnd += len; | |
1507 | } | |
1da177e4 | 1508 | |
362d5204 DB |
1509 | /* If we had window pressure, start recovering it |
1510 | * once our rwnd had reached the accumulated pressure | |
1511 | * threshold. The idea is to recover slowly, but up | |
1512 | * to the initial advertised window. | |
1513 | */ | |
1636098c | 1514 | if (asoc->rwnd_press) { |
362d5204 DB |
1515 | int change = min(asoc->pathmtu, asoc->rwnd_press); |
1516 | asoc->rwnd += change; | |
1517 | asoc->rwnd_press -= change; | |
1518 | } | |
4d3c46e6 | 1519 | |
362d5204 DB |
1520 | pr_debug("%s: asoc:%p rwnd increased by %d to (%u, %u) - %u\n", |
1521 | __func__, asoc, len, asoc->rwnd, asoc->rwnd_over, | |
1522 | asoc->a_rwnd); | |
1da177e4 LT |
1523 | |
1524 | /* Send a window update SACK if the rwnd has increased by at least the | |
1525 | * minimum of the association's PMTU and half of the receive buffer. | |
1526 | * The algorithm used is similar to the one described in | |
1527 | * Section 4.2.3.3 of RFC 1122. | |
1528 | */ | |
362d5204 | 1529 | if (sctp_peer_needs_update(asoc)) { |
1da177e4 | 1530 | asoc->a_rwnd = asoc->rwnd; |
bb33381d DB |
1531 | |
1532 | pr_debug("%s: sending window update SACK- asoc:%p rwnd:%u " | |
1533 | "a_rwnd:%u\n", __func__, asoc, asoc->rwnd, | |
1534 | asoc->a_rwnd); | |
1535 | ||
1da177e4 LT |
1536 | sack = sctp_make_sack(asoc); |
1537 | if (!sack) | |
1538 | return; | |
1539 | ||
1540 | asoc->peer.sack_needed = 0; | |
1541 | ||
cea8768f | 1542 | sctp_outq_tail(&asoc->outqueue, sack, GFP_ATOMIC); |
1da177e4 LT |
1543 | |
1544 | /* Stop the SACK timer. */ | |
1545 | timer = &asoc->timers[SCTP_EVENT_TIMEOUT_SACK]; | |
25cc4ae9 | 1546 | if (del_timer(timer)) |
1da177e4 LT |
1547 | sctp_association_put(asoc); |
1548 | } | |
1549 | } | |
1550 | ||
362d5204 DB |
1551 | /* Decrease asoc's rwnd by len. */ |
1552 | void sctp_assoc_rwnd_decrease(struct sctp_association *asoc, unsigned int len) | |
1553 | { | |
1554 | int rx_count; | |
1555 | int over = 0; | |
1556 | ||
1557 | if (unlikely(!asoc->rwnd || asoc->rwnd_over)) | |
1558 | pr_debug("%s: association:%p has asoc->rwnd:%u, " | |
1559 | "asoc->rwnd_over:%u!\n", __func__, asoc, | |
1560 | asoc->rwnd, asoc->rwnd_over); | |
1561 | ||
1562 | if (asoc->ep->rcvbuf_policy) | |
1563 | rx_count = atomic_read(&asoc->rmem_alloc); | |
1564 | else | |
1565 | rx_count = atomic_read(&asoc->base.sk->sk_rmem_alloc); | |
1566 | ||
1567 | /* If we've reached or overflowed our receive buffer, announce | |
1568 | * a 0 rwnd if rwnd would still be positive. Store the | |
1569 | * the potential pressure overflow so that the window can be restored | |
1570 | * back to original value. | |
1571 | */ | |
1572 | if (rx_count >= asoc->base.sk->sk_rcvbuf) | |
1573 | over = 1; | |
1574 | ||
1575 | if (asoc->rwnd >= len) { | |
1576 | asoc->rwnd -= len; | |
1577 | if (over) { | |
1578 | asoc->rwnd_press += asoc->rwnd; | |
1579 | asoc->rwnd = 0; | |
1580 | } | |
1581 | } else { | |
58b94d88 | 1582 | asoc->rwnd_over += len - asoc->rwnd; |
362d5204 DB |
1583 | asoc->rwnd = 0; |
1584 | } | |
1585 | ||
1586 | pr_debug("%s: asoc:%p rwnd decreased by %d to (%u, %u, %u)\n", | |
1587 | __func__, asoc, len, asoc->rwnd, asoc->rwnd_over, | |
1588 | asoc->rwnd_press); | |
1589 | } | |
1da177e4 LT |
1590 | |
1591 | /* Build the bind address list for the association based on info from the | |
1592 | * local endpoint and the remote peer. | |
1593 | */ | |
3182cd84 | 1594 | int sctp_assoc_set_bind_addr_from_ep(struct sctp_association *asoc, |
1c662018 | 1595 | enum sctp_scope scope, gfp_t gfp) |
1da177e4 | 1596 | { |
1da177e4 LT |
1597 | int flags; |
1598 | ||
1599 | /* Use scoping rules to determine the subset of addresses from | |
1600 | * the endpoint. | |
1601 | */ | |
1da177e4 LT |
1602 | flags = (PF_INET6 == asoc->base.sk->sk_family) ? SCTP_ADDR6_ALLOWED : 0; |
1603 | if (asoc->peer.ipv4_address) | |
1604 | flags |= SCTP_ADDR4_PEERSUPP; | |
1605 | if (asoc->peer.ipv6_address) | |
1606 | flags |= SCTP_ADDR6_PEERSUPP; | |
1607 | ||
4db67e80 EB |
1608 | return sctp_bind_addr_copy(sock_net(asoc->base.sk), |
1609 | &asoc->base.bind_addr, | |
1da177e4 LT |
1610 | &asoc->ep->base.bind_addr, |
1611 | scope, gfp, flags); | |
1612 | } | |
1613 | ||
1614 | /* Build the association's bind address list from the cookie. */ | |
1615 | int sctp_assoc_set_bind_addr_from_cookie(struct sctp_association *asoc, | |
3182cd84 | 1616 | struct sctp_cookie *cookie, |
dd0fc66f | 1617 | gfp_t gfp) |
1da177e4 LT |
1618 | { |
1619 | int var_size2 = ntohs(cookie->peer_init->chunk_hdr.length); | |
1620 | int var_size3 = cookie->raw_addr_list_len; | |
1621 | __u8 *raw = (__u8 *)cookie->peer_init + var_size2; | |
1622 | ||
1623 | return sctp_raw_to_bind_addrs(&asoc->base.bind_addr, raw, var_size3, | |
1624 | asoc->ep->base.bind_addr.port, gfp); | |
1625 | } | |
1626 | ||
d808ad9a YH |
1627 | /* Lookup laddr in the bind address list of an association. */ |
1628 | int sctp_assoc_lookup_laddr(struct sctp_association *asoc, | |
1da177e4 LT |
1629 | const union sctp_addr *laddr) |
1630 | { | |
559cf710 | 1631 | int found = 0; |
1da177e4 | 1632 | |
1da177e4 LT |
1633 | if ((asoc->base.bind_addr.port == ntohs(laddr->v4.sin_port)) && |
1634 | sctp_bind_addr_match(&asoc->base.bind_addr, laddr, | |
559cf710 | 1635 | sctp_sk(asoc->base.sk))) |
1da177e4 | 1636 | found = 1; |
1da177e4 | 1637 | |
1da177e4 LT |
1638 | return found; |
1639 | } | |
07d93967 VY |
1640 | |
1641 | /* Set an association id for a given association */ | |
1642 | int sctp_assoc_set_id(struct sctp_association *asoc, gfp_t gfp) | |
1643 | { | |
d0164adc | 1644 | bool preload = gfpflags_allow_blocking(gfp); |
94960e8c | 1645 | int ret; |
c6ba68a2 VY |
1646 | |
1647 | /* If the id is already assigned, keep it. */ | |
1648 | if (asoc->assoc_id) | |
94960e8c | 1649 | return 0; |
07d93967 | 1650 | |
94960e8c TH |
1651 | if (preload) |
1652 | idr_preload(gfp); | |
07d93967 | 1653 | spin_lock_bh(&sctp_assocs_id_lock); |
713e00a3 JL |
1654 | /* 0 is not a valid assoc_id, must be >= 1 */ |
1655 | ret = idr_alloc_cyclic(&sctp_assocs_id, asoc, 1, 0, GFP_NOWAIT); | |
07d93967 | 1656 | spin_unlock_bh(&sctp_assocs_id_lock); |
94960e8c TH |
1657 | if (preload) |
1658 | idr_preload_end(); | |
1659 | if (ret < 0) | |
1660 | return ret; | |
07d93967 | 1661 | |
94960e8c TH |
1662 | asoc->assoc_id = (sctp_assoc_t)ret; |
1663 | return 0; | |
07d93967 | 1664 | } |
a08de64d | 1665 | |
8b4472cc WY |
1666 | /* Free the ASCONF queue */ |
1667 | static void sctp_assoc_free_asconf_queue(struct sctp_association *asoc) | |
1668 | { | |
1669 | struct sctp_chunk *asconf; | |
1670 | struct sctp_chunk *tmp; | |
1671 | ||
1672 | list_for_each_entry_safe(asconf, tmp, &asoc->addip_chunk_list, list) { | |
1673 | list_del_init(&asconf->list); | |
1674 | sctp_chunk_free(asconf); | |
1675 | } | |
1676 | } | |
1677 | ||
a08de64d VY |
1678 | /* Free asconf_ack cache */ |
1679 | static void sctp_assoc_free_asconf_acks(struct sctp_association *asoc) | |
1680 | { | |
1681 | struct sctp_chunk *ack; | |
1682 | struct sctp_chunk *tmp; | |
1683 | ||
1684 | list_for_each_entry_safe(ack, tmp, &asoc->asconf_ack_list, | |
1685 | transmitted_list) { | |
1686 | list_del_init(&ack->transmitted_list); | |
1687 | sctp_chunk_free(ack); | |
1688 | } | |
1689 | } | |
1690 | ||
1691 | /* Clean up the ASCONF_ACK queue */ | |
1692 | void sctp_assoc_clean_asconf_ack_cache(const struct sctp_association *asoc) | |
1693 | { | |
1694 | struct sctp_chunk *ack; | |
1695 | struct sctp_chunk *tmp; | |
1696 | ||
25985edc | 1697 | /* We can remove all the entries from the queue up to |
a08de64d VY |
1698 | * the "Peer-Sequence-Number". |
1699 | */ | |
1700 | list_for_each_entry_safe(ack, tmp, &asoc->asconf_ack_list, | |
1701 | transmitted_list) { | |
1702 | if (ack->subh.addip_hdr->serial == | |
1703 | htonl(asoc->peer.addip_serial)) | |
1704 | break; | |
1705 | ||
1706 | list_del_init(&ack->transmitted_list); | |
1707 | sctp_chunk_free(ack); | |
1708 | } | |
1709 | } | |
1710 | ||
1711 | /* Find the ASCONF_ACK whose serial number matches ASCONF */ | |
1712 | struct sctp_chunk *sctp_assoc_lookup_asconf_ack( | |
1713 | const struct sctp_association *asoc, | |
1714 | __be32 serial) | |
1715 | { | |
a8699814 | 1716 | struct sctp_chunk *ack; |
a08de64d VY |
1717 | |
1718 | /* Walk through the list of cached ASCONF-ACKs and find the | |
1719 | * ack chunk whose serial number matches that of the request. | |
1720 | */ | |
1721 | list_for_each_entry(ack, &asoc->asconf_ack_list, transmitted_list) { | |
b69040d8 DB |
1722 | if (sctp_chunk_pending(ack)) |
1723 | continue; | |
a08de64d VY |
1724 | if (ack->subh.addip_hdr->serial == serial) { |
1725 | sctp_chunk_hold(ack); | |
a8699814 | 1726 | return ack; |
a08de64d VY |
1727 | } |
1728 | } | |
1729 | ||
a8699814 | 1730 | return NULL; |
a08de64d | 1731 | } |
a000c01e WY |
1732 | |
1733 | void sctp_asconf_queue_teardown(struct sctp_association *asoc) | |
1734 | { | |
1735 | /* Free any cached ASCONF_ACK chunk. */ | |
1736 | sctp_assoc_free_asconf_acks(asoc); | |
1737 | ||
1738 | /* Free the ASCONF queue. */ | |
1739 | sctp_assoc_free_asconf_queue(asoc); | |
1740 | ||
1741 | /* Free any cached ASCONF chunk. */ | |
1742 | if (asoc->addip_last_asconf) | |
1743 | sctp_chunk_free(asoc->addip_last_asconf); | |
1744 | } |