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Merge git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending
[linux-2.6.git] / net / sctp / sm_sideeffect.c
blob8aab894aeabeecb410c9763e33824f5dec7a6c91
1 /* SCTP kernel implementation
2 * (C) Copyright IBM Corp. 2001, 2004
3 * Copyright (c) 1999 Cisco, Inc.
4 * Copyright (c) 1999-2001 Motorola, Inc.
5 *
6 * This file is part of the SCTP kernel implementation
7 *
8 * These functions work with the state functions in sctp_sm_statefuns.c
9 * to implement that state operations. These functions implement the
10 * steps which require modifying existing data structures.
11 *
12 * This SCTP implementation is free software;
13 * you can redistribute it and/or modify it under the terms of
14 * the GNU General Public License as published by
15 * the Free Software Foundation; either version 2, or (at your option)
16 * any later version.
17 *
18 * This SCTP implementation is distributed in the hope that it
19 * will be useful, but WITHOUT ANY WARRANTY; without even the implied
20 * ************************
21 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
22 * See the GNU General Public License for more details.
23 *
24 * You should have received a copy of the GNU General Public License
25 * along with GNU CC; see the file COPYING. If not, write to
26 * the Free Software Foundation, 59 Temple Place - Suite 330,
27 * Boston, MA 02111-1307, USA.
28 *
29 * Please send any bug reports or fixes you make to the
30 * email address(es):
31 * lksctp developers <lksctp-developers@lists.sourceforge.net>
32 *
33 * Or submit a bug report through the following website:
34 * http://www.sf.net/projects/lksctp
35 *
36 * Written or modified by:
37 * La Monte H.P. Yarroll <piggy@acm.org>
38 * Karl Knutson <karl@athena.chicago.il.us>
39 * Jon Grimm <jgrimm@austin.ibm.com>
40 * Hui Huang <hui.huang@nokia.com>
41 * Dajiang Zhang <dajiang.zhang@nokia.com>
42 * Daisy Chang <daisyc@us.ibm.com>
43 * Sridhar Samudrala <sri@us.ibm.com>
44 * Ardelle Fan <ardelle.fan@intel.com>
45 *
46 * Any bugs reported given to us we will try to fix... any fixes shared will
47 * be incorporated into the next SCTP release.
48 */
49
50 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
51
52 #include <linux/skbuff.h>
53 #include <linux/types.h>
54 #include <linux/socket.h>
55 #include <linux/ip.h>
56 #include <linux/gfp.h>
57 #include <net/sock.h>
58 #include <net/sctp/sctp.h>
59 #include <net/sctp/sm.h>
60
61 static int sctp_cmd_interpreter(sctp_event_t event_type,
62 sctp_subtype_t subtype,
63 sctp_state_t state,
64 struct sctp_endpoint *ep,
65 struct sctp_association *asoc,
66 void *event_arg,
67 sctp_disposition_t status,
68 sctp_cmd_seq_t *commands,
69 gfp_t gfp);
70 static int sctp_side_effects(sctp_event_t event_type, sctp_subtype_t subtype,
71 sctp_state_t state,
72 struct sctp_endpoint *ep,
73 struct sctp_association *asoc,
74 void *event_arg,
75 sctp_disposition_t status,
76 sctp_cmd_seq_t *commands,
77 gfp_t gfp);
78
79 static void sctp_cmd_hb_timer_update(sctp_cmd_seq_t *cmds,
80 struct sctp_transport *t);
81 /********************************************************************
82 * Helper functions
83 ********************************************************************/
84
85 /* A helper function for delayed processing of INET ECN CE bit. */
86 static void sctp_do_ecn_ce_work(struct sctp_association *asoc,
87 __u32 lowest_tsn)
88 {
89 /* Save the TSN away for comparison when we receive CWR */
90
91 asoc->last_ecne_tsn = lowest_tsn;
92 asoc->need_ecne = 1;
93 }
94
95 /* Helper function for delayed processing of SCTP ECNE chunk. */
96 /* RFC 2960 Appendix A
97 *
98 * RFC 2481 details a specific bit for a sender to send in
99 * the header of its next outbound TCP segment to indicate to
100 * its peer that it has reduced its congestion window. This
101 * is termed the CWR bit. For SCTP the same indication is made
102 * by including the CWR chunk. This chunk contains one data
103 * element, i.e. the TSN number that was sent in the ECNE chunk.
104 * This element represents the lowest TSN number in the datagram
105 * that was originally marked with the CE bit.
106 */
107 static struct sctp_chunk *sctp_do_ecn_ecne_work(struct sctp_association *asoc,
108 __u32 lowest_tsn,
109 struct sctp_chunk *chunk)
110 {
111 struct sctp_chunk *repl;
112
113 /* Our previously transmitted packet ran into some congestion
114 * so we should take action by reducing cwnd and ssthresh
115 * and then ACK our peer that we we've done so by
116 * sending a CWR.
117 */
118
119 /* First, try to determine if we want to actually lower
120 * our cwnd variables. Only lower them if the ECNE looks more
121 * recent than the last response.
122 */
123 if (TSN_lt(asoc->last_cwr_tsn, lowest_tsn)) {
124 struct sctp_transport *transport;
125
126 /* Find which transport's congestion variables
127 * need to be adjusted.
128 */
129 transport = sctp_assoc_lookup_tsn(asoc, lowest_tsn);
130
131 /* Update the congestion variables. */
132 if (transport)
133 sctp_transport_lower_cwnd(transport,
134 SCTP_LOWER_CWND_ECNE);
135 asoc->last_cwr_tsn = lowest_tsn;
136 }
137
138 /* Always try to quiet the other end. In case of lost CWR,
139 * resend last_cwr_tsn.
140 */
141 repl = sctp_make_cwr(asoc, asoc->last_cwr_tsn, chunk);
142
143 /* If we run out of memory, it will look like a lost CWR. We'll
144 * get back in sync eventually.
145 */
146 return repl;
147 }
148
149 /* Helper function to do delayed processing of ECN CWR chunk. */
150 static void sctp_do_ecn_cwr_work(struct sctp_association *asoc,
151 __u32 lowest_tsn)
152 {
153 /* Turn off ECNE getting auto-prepended to every outgoing
154 * packet
155 */
156 asoc->need_ecne = 0;
157 }
158
159 /* Generate SACK if necessary. We call this at the end of a packet. */
160 static int sctp_gen_sack(struct sctp_association *asoc, int force,
161 sctp_cmd_seq_t *commands)
162 {
163 __u32 ctsn, max_tsn_seen;
164 struct sctp_chunk *sack;
165 struct sctp_transport *trans = asoc->peer.last_data_from;
166 int error = 0;
167
168 if (force ||
169 (!trans && (asoc->param_flags & SPP_SACKDELAY_DISABLE)) ||
170 (trans && (trans->param_flags & SPP_SACKDELAY_DISABLE)))
171 asoc->peer.sack_needed = 1;
172
173 ctsn = sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map);
174 max_tsn_seen = sctp_tsnmap_get_max_tsn_seen(&asoc->peer.tsn_map);
175
176 /* From 12.2 Parameters necessary per association (i.e. the TCB):
177 *
178 * Ack State : This flag indicates if the next received packet
179 * : is to be responded to with a SACK. ...
180 * : When DATA chunks are out of order, SACK's
181 * : are not delayed (see Section 6).
182 *
183 * [This is actually not mentioned in Section 6, but we
184 * implement it here anyway. --piggy]
185 */
186 if (max_tsn_seen != ctsn)
187 asoc->peer.sack_needed = 1;
188
189 /* From 6.2 Acknowledgement on Reception of DATA Chunks:
190 *
191 * Section 4.2 of [RFC2581] SHOULD be followed. Specifically,
192 * an acknowledgement SHOULD be generated for at least every
193 * second packet (not every second DATA chunk) received, and
194 * SHOULD be generated within 200 ms of the arrival of any
195 * unacknowledged DATA chunk. ...
196 */
197 if (!asoc->peer.sack_needed) {
198 asoc->peer.sack_cnt++;
199
200 /* Set the SACK delay timeout based on the
201 * SACK delay for the last transport
202 * data was received from, or the default
203 * for the association.
204 */
205 if (trans) {
206 /* We will need a SACK for the next packet. */
207 if (asoc->peer.sack_cnt >= trans->sackfreq - 1)
208 asoc->peer.sack_needed = 1;
209
210 asoc->timeouts[SCTP_EVENT_TIMEOUT_SACK] =
211 trans->sackdelay;
212 } else {
213 /* We will need a SACK for the next packet. */
214 if (asoc->peer.sack_cnt >= asoc->sackfreq - 1)
215 asoc->peer.sack_needed = 1;
216
217 asoc->timeouts[SCTP_EVENT_TIMEOUT_SACK] =
218 asoc->sackdelay;
219 }
220
221 /* Restart the SACK timer. */
222 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART,
223 SCTP_TO(SCTP_EVENT_TIMEOUT_SACK));
224 } else {
225 asoc->a_rwnd = asoc->rwnd;
226 sack = sctp_make_sack(asoc);
227 if (!sack)
228 goto nomem;
229
230 asoc->peer.sack_needed = 0;
231 asoc->peer.sack_cnt = 0;
232
233 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(sack));
234
235 /* Stop the SACK timer. */
236 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP,
237 SCTP_TO(SCTP_EVENT_TIMEOUT_SACK));
238 }
239
240 return error;
241 nomem:
242 error = -ENOMEM;
243 return error;
244 }
245
246 /* When the T3-RTX timer expires, it calls this function to create the
247 * relevant state machine event.
248 */
249 void sctp_generate_t3_rtx_event(unsigned long peer)
250 {
251 int error;
252 struct sctp_transport *transport = (struct sctp_transport *) peer;
253 struct sctp_association *asoc = transport->asoc;
254 struct net *net = sock_net(asoc->base.sk);
255
256 /* Check whether a task is in the sock. */
257
258 sctp_bh_lock_sock(asoc->base.sk);
259 if (sock_owned_by_user(asoc->base.sk)) {
260 SCTP_DEBUG_PRINTK("%s:Sock is busy.\n", __func__);
261
262 /* Try again later. */
263 if (!mod_timer(&transport->T3_rtx_timer, jiffies + (HZ/20)))
264 sctp_transport_hold(transport);
265 goto out_unlock;
266 }
267
268 /* Is this transport really dead and just waiting around for
269 * the timer to let go of the reference?
270 */
271 if (transport->dead)
272 goto out_unlock;
273
274 /* Run through the state machine. */
275 error = sctp_do_sm(net, SCTP_EVENT_T_TIMEOUT,
276 SCTP_ST_TIMEOUT(SCTP_EVENT_TIMEOUT_T3_RTX),
277 asoc->state,
278 asoc->ep, asoc,
279 transport, GFP_ATOMIC);
280
281 if (error)
282 asoc->base.sk->sk_err = -error;
283
284 out_unlock:
285 sctp_bh_unlock_sock(asoc->base.sk);
286 sctp_transport_put(transport);
287 }
288
289 /* This is a sa interface for producing timeout events. It works
290 * for timeouts which use the association as their parameter.
291 */
292 static void sctp_generate_timeout_event(struct sctp_association *asoc,
293 sctp_event_timeout_t timeout_type)
294 {
295 struct net *net = sock_net(asoc->base.sk);
296 int error = 0;
297
298 sctp_bh_lock_sock(asoc->base.sk);
299 if (sock_owned_by_user(asoc->base.sk)) {
300 SCTP_DEBUG_PRINTK("%s:Sock is busy: timer %d\n",
301 __func__,
302 timeout_type);
303
304 /* Try again later. */
305 if (!mod_timer(&asoc->timers[timeout_type], jiffies + (HZ/20)))
306 sctp_association_hold(asoc);
307 goto out_unlock;
308 }
309
310 /* Is this association really dead and just waiting around for
311 * the timer to let go of the reference?
312 */
313 if (asoc->base.dead)
314 goto out_unlock;
315
316 /* Run through the state machine. */
317 error = sctp_do_sm(net, SCTP_EVENT_T_TIMEOUT,
318 SCTP_ST_TIMEOUT(timeout_type),
319 asoc->state, asoc->ep, asoc,
320 (void *)timeout_type, GFP_ATOMIC);
321
322 if (error)
323 asoc->base.sk->sk_err = -error;
324
325 out_unlock:
326 sctp_bh_unlock_sock(asoc->base.sk);
327 sctp_association_put(asoc);
328 }
329
330 static void sctp_generate_t1_cookie_event(unsigned long data)
331 {
332 struct sctp_association *asoc = (struct sctp_association *) data;
333 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T1_COOKIE);
334 }
335
336 static void sctp_generate_t1_init_event(unsigned long data)
337 {
338 struct sctp_association *asoc = (struct sctp_association *) data;
339 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T1_INIT);
340 }
341
342 static void sctp_generate_t2_shutdown_event(unsigned long data)
343 {
344 struct sctp_association *asoc = (struct sctp_association *) data;
345 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T2_SHUTDOWN);
346 }
347
348 static void sctp_generate_t4_rto_event(unsigned long data)
349 {
350 struct sctp_association *asoc = (struct sctp_association *) data;
351 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T4_RTO);
352 }
353
354 static void sctp_generate_t5_shutdown_guard_event(unsigned long data)
355 {
356 struct sctp_association *asoc = (struct sctp_association *)data;
357 sctp_generate_timeout_event(asoc,
358 SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD);
359
360 } /* sctp_generate_t5_shutdown_guard_event() */
361
362 static void sctp_generate_autoclose_event(unsigned long data)
363 {
364 struct sctp_association *asoc = (struct sctp_association *) data;
365 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_AUTOCLOSE);
366 }
367
368 /* Generate a heart beat event. If the sock is busy, reschedule. Make
369 * sure that the transport is still valid.
370 */
371 void sctp_generate_heartbeat_event(unsigned long data)
372 {
373 int error = 0;
374 struct sctp_transport *transport = (struct sctp_transport *) data;
375 struct sctp_association *asoc = transport->asoc;
376 struct net *net = sock_net(asoc->base.sk);
377
378 sctp_bh_lock_sock(asoc->base.sk);
379 if (sock_owned_by_user(asoc->base.sk)) {
380 SCTP_DEBUG_PRINTK("%s:Sock is busy.\n", __func__);
381
382 /* Try again later. */
383 if (!mod_timer(&transport->hb_timer, jiffies + (HZ/20)))
384 sctp_transport_hold(transport);
385 goto out_unlock;
386 }
387
388 /* Is this structure just waiting around for us to actually
389 * get destroyed?
390 */
391 if (transport->dead)
392 goto out_unlock;
393
394 error = sctp_do_sm(net, SCTP_EVENT_T_TIMEOUT,
395 SCTP_ST_TIMEOUT(SCTP_EVENT_TIMEOUT_HEARTBEAT),
396 asoc->state, asoc->ep, asoc,
397 transport, GFP_ATOMIC);
398
399 if (error)
400 asoc->base.sk->sk_err = -error;
401
402 out_unlock:
403 sctp_bh_unlock_sock(asoc->base.sk);
404 sctp_transport_put(transport);
405 }
406
407 /* Handle the timeout of the ICMP protocol unreachable timer. Trigger
408 * the correct state machine transition that will close the association.
409 */
410 void sctp_generate_proto_unreach_event(unsigned long data)
411 {
412 struct sctp_transport *transport = (struct sctp_transport *) data;
413 struct sctp_association *asoc = transport->asoc;
414 struct net *net = sock_net(asoc->base.sk);
415
416 sctp_bh_lock_sock(asoc->base.sk);
417 if (sock_owned_by_user(asoc->base.sk)) {
418 SCTP_DEBUG_PRINTK("%s:Sock is busy.\n", __func__);
419
420 /* Try again later. */
421 if (!mod_timer(&transport->proto_unreach_timer,
422 jiffies + (HZ/20)))
423 sctp_association_hold(asoc);
424 goto out_unlock;
425 }
426
427 /* Is this structure just waiting around for us to actually
428 * get destroyed?
429 */
430 if (asoc->base.dead)
431 goto out_unlock;
432
433 sctp_do_sm(net, SCTP_EVENT_T_OTHER,
434 SCTP_ST_OTHER(SCTP_EVENT_ICMP_PROTO_UNREACH),
435 asoc->state, asoc->ep, asoc, transport, GFP_ATOMIC);
436
437 out_unlock:
438 sctp_bh_unlock_sock(asoc->base.sk);
439 sctp_association_put(asoc);
440 }
441
442
443 /* Inject a SACK Timeout event into the state machine. */
444 static void sctp_generate_sack_event(unsigned long data)
445 {
446 struct sctp_association *asoc = (struct sctp_association *) data;
447 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_SACK);
448 }
449
450 sctp_timer_event_t *sctp_timer_events[SCTP_NUM_TIMEOUT_TYPES] = {
451 NULL,
452 sctp_generate_t1_cookie_event,
453 sctp_generate_t1_init_event,
454 sctp_generate_t2_shutdown_event,
455 NULL,
456 sctp_generate_t4_rto_event,
457 sctp_generate_t5_shutdown_guard_event,
458 NULL,
459 sctp_generate_sack_event,
460 sctp_generate_autoclose_event,
461 };
462
463
464 /* RFC 2960 8.2 Path Failure Detection
465 *
466 * When its peer endpoint is multi-homed, an endpoint should keep a
467 * error counter for each of the destination transport addresses of the
468 * peer endpoint.
469 *
470 * Each time the T3-rtx timer expires on any address, or when a
471 * HEARTBEAT sent to an idle address is not acknowledged within a RTO,
472 * the error counter of that destination address will be incremented.
473 * When the value in the error counter exceeds the protocol parameter
474 * 'Path.Max.Retrans' of that destination address, the endpoint should
475 * mark the destination transport address as inactive, and a
476 * notification SHOULD be sent to the upper layer.
477 *
478 */
479 static void sctp_do_8_2_transport_strike(sctp_cmd_seq_t *commands,
480 struct sctp_association *asoc,
481 struct sctp_transport *transport,
482 int is_hb)
483 {
484 /* The check for association's overall error counter exceeding the
485 * threshold is done in the state function.
486 */
487 /* We are here due to a timer expiration. If the timer was
488 * not a HEARTBEAT, then normal error tracking is done.
489 * If the timer was a heartbeat, we only increment error counts
490 * when we already have an outstanding HEARTBEAT that has not
491 * been acknowledged.
492 * Additionally, some tranport states inhibit error increments.
493 */
494 if (!is_hb) {
495 asoc->overall_error_count++;
496 if (transport->state != SCTP_INACTIVE)
497 transport->error_count++;
498 } else if (transport->hb_sent) {
499 if (transport->state != SCTP_UNCONFIRMED)
500 asoc->overall_error_count++;
501 if (transport->state != SCTP_INACTIVE)
502 transport->error_count++;
503 }
504
505 /* If the transport error count is greater than the pf_retrans
506 * threshold, and less than pathmaxrtx, then mark this transport
507 * as Partially Failed, ee SCTP Quick Failover Draft, secon 5.1,
508 * point 1
509 */
510 if ((transport->state != SCTP_PF) &&
511 (asoc->pf_retrans < transport->pathmaxrxt) &&
512 (transport->error_count > asoc->pf_retrans)) {
513
514 sctp_assoc_control_transport(asoc, transport,
515 SCTP_TRANSPORT_PF,
516 0);
517
518 /* Update the hb timer to resend a heartbeat every rto */
519 sctp_cmd_hb_timer_update(commands, transport);
520 }
521
522 if (transport->state != SCTP_INACTIVE &&
523 (transport->error_count > transport->pathmaxrxt)) {
524 SCTP_DEBUG_PRINTK_IPADDR("transport_strike:association %p",
525 " transport IP: port:%d failed.\n",
526 asoc,
527 (&transport->ipaddr),
528 ntohs(transport->ipaddr.v4.sin_port));
529 sctp_assoc_control_transport(asoc, transport,
530 SCTP_TRANSPORT_DOWN,
531 SCTP_FAILED_THRESHOLD);
532 }
533
534 /* E2) For the destination address for which the timer
535 * expires, set RTO <- RTO * 2 ("back off the timer"). The
536 * maximum value discussed in rule C7 above (RTO.max) may be
537 * used to provide an upper bound to this doubling operation.
538 *
539 * Special Case: the first HB doesn't trigger exponential backoff.
540 * The first unacknowledged HB triggers it. We do this with a flag
541 * that indicates that we have an outstanding HB.
542 */
543 if (!is_hb || transport->hb_sent) {
544 transport->rto = min((transport->rto * 2), transport->asoc->rto_max);
545 sctp_max_rto(asoc, transport);
546 }
547 }
548
549 /* Worker routine to handle INIT command failure. */
550 static void sctp_cmd_init_failed(sctp_cmd_seq_t *commands,
551 struct sctp_association *asoc,
552 unsigned int error)
553 {
554 struct sctp_ulpevent *event;
555
556 event = sctp_ulpevent_make_assoc_change(asoc,0, SCTP_CANT_STR_ASSOC,
557 (__u16)error, 0, 0, NULL,
558 GFP_ATOMIC);
559
560 if (event)
561 sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP,
562 SCTP_ULPEVENT(event));
563
564 sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE,
565 SCTP_STATE(SCTP_STATE_CLOSED));
566
567 /* SEND_FAILED sent later when cleaning up the association. */
568 asoc->outqueue.error = error;
569 sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL());
570 }
571
572 /* Worker routine to handle SCTP_CMD_ASSOC_FAILED. */
573 static void sctp_cmd_assoc_failed(sctp_cmd_seq_t *commands,
574 struct sctp_association *asoc,
575 sctp_event_t event_type,
576 sctp_subtype_t subtype,
577 struct sctp_chunk *chunk,
578 unsigned int error)
579 {
580 struct sctp_ulpevent *event;
581 struct sctp_chunk *abort;
582 /* Cancel any partial delivery in progress. */
583 sctp_ulpq_abort_pd(&asoc->ulpq, GFP_ATOMIC);
584
585 if (event_type == SCTP_EVENT_T_CHUNK && subtype.chunk == SCTP_CID_ABORT)
586 event = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_COMM_LOST,
587 (__u16)error, 0, 0, chunk,
588 GFP_ATOMIC);
589 else
590 event = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_COMM_LOST,
591 (__u16)error, 0, 0, NULL,
592 GFP_ATOMIC);
593 if (event)
594 sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP,
595 SCTP_ULPEVENT(event));
596
597 if (asoc->overall_error_count >= asoc->max_retrans) {
598 abort = sctp_make_violation_max_retrans(asoc, chunk);
599 if (abort)
600 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
601 SCTP_CHUNK(abort));
602 }
603
604 sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE,
605 SCTP_STATE(SCTP_STATE_CLOSED));
606
607 /* SEND_FAILED sent later when cleaning up the association. */
608 asoc->outqueue.error = error;
609 sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL());
610 }
611
612 /* Process an init chunk (may be real INIT/INIT-ACK or an embedded INIT
613 * inside the cookie. In reality, this is only used for INIT-ACK processing
614 * since all other cases use "temporary" associations and can do all
615 * their work in statefuns directly.
616 */
617 static int sctp_cmd_process_init(sctp_cmd_seq_t *commands,
618 struct sctp_association *asoc,
619 struct sctp_chunk *chunk,
620 sctp_init_chunk_t *peer_init,
621 gfp_t gfp)
622 {
623 int error;
624
625 /* We only process the init as a sideeffect in a single
626 * case. This is when we process the INIT-ACK. If we
627 * fail during INIT processing (due to malloc problems),
628 * just return the error and stop processing the stack.
629 */
630 if (!sctp_process_init(asoc, chunk, sctp_source(chunk), peer_init, gfp))
631 error = -ENOMEM;
632 else
633 error = 0;
634
635 return error;
636 }
637
638 /* Helper function to break out starting up of heartbeat timers. */
639 static void sctp_cmd_hb_timers_start(sctp_cmd_seq_t *cmds,
640 struct sctp_association *asoc)
641 {
642 struct sctp_transport *t;
643
644 /* Start a heartbeat timer for each transport on the association.
645 * hold a reference on the transport to make sure none of
646 * the needed data structures go away.
647 */
648 list_for_each_entry(t, &asoc->peer.transport_addr_list, transports) {
649
650 if (!mod_timer(&t->hb_timer, sctp_transport_timeout(t)))
651 sctp_transport_hold(t);
652 }
653 }
654
655 static void sctp_cmd_hb_timers_stop(sctp_cmd_seq_t *cmds,
656 struct sctp_association *asoc)
657 {
658 struct sctp_transport *t;
659
660 /* Stop all heartbeat timers. */
661
662 list_for_each_entry(t, &asoc->peer.transport_addr_list,
663 transports) {
664 if (del_timer(&t->hb_timer))
665 sctp_transport_put(t);
666 }
667 }
668
669 /* Helper function to stop any pending T3-RTX timers */
670 static void sctp_cmd_t3_rtx_timers_stop(sctp_cmd_seq_t *cmds,
671 struct sctp_association *asoc)
672 {
673 struct sctp_transport *t;
674
675 list_for_each_entry(t, &asoc->peer.transport_addr_list,
676 transports) {
677 if (del_timer(&t->T3_rtx_timer))
678 sctp_transport_put(t);
679 }
680 }
681
682
683 /* Helper function to update the heartbeat timer. */
684 static void sctp_cmd_hb_timer_update(sctp_cmd_seq_t *cmds,
685 struct sctp_transport *t)
686 {
687 /* Update the heartbeat timer. */
688 if (!mod_timer(&t->hb_timer, sctp_transport_timeout(t)))
689 sctp_transport_hold(t);
690 }
691
692 /* Helper function to handle the reception of an HEARTBEAT ACK. */
693 static void sctp_cmd_transport_on(sctp_cmd_seq_t *cmds,
694 struct sctp_association *asoc,
695 struct sctp_transport *t,
696 struct sctp_chunk *chunk)
697 {
698 sctp_sender_hb_info_t *hbinfo;
699 int was_unconfirmed = 0;
700
701 /* 8.3 Upon the receipt of the HEARTBEAT ACK, the sender of the
702 * HEARTBEAT should clear the error counter of the destination
703 * transport address to which the HEARTBEAT was sent.
704 */
705 t->error_count = 0;
706
707 /*
708 * Although RFC4960 specifies that the overall error count must
709 * be cleared when a HEARTBEAT ACK is received, we make an
710 * exception while in SHUTDOWN PENDING. If the peer keeps its
711 * window shut forever, we may never be able to transmit our
712 * outstanding data and rely on the retransmission limit be reached
713 * to shutdown the association.
714 */
715 if (t->asoc->state != SCTP_STATE_SHUTDOWN_PENDING)
716 t->asoc->overall_error_count = 0;
717
718 /* Clear the hb_sent flag to signal that we had a good
719 * acknowledgement.
720 */
721 t->hb_sent = 0;
722
723 /* Mark the destination transport address as active if it is not so
724 * marked.
725 */
726 if ((t->state == SCTP_INACTIVE) || (t->state == SCTP_UNCONFIRMED)) {
727 was_unconfirmed = 1;
728 sctp_assoc_control_transport(asoc, t, SCTP_TRANSPORT_UP,
729 SCTP_HEARTBEAT_SUCCESS);
730 }
731
732 if (t->state == SCTP_PF)
733 sctp_assoc_control_transport(asoc, t, SCTP_TRANSPORT_UP,
734 SCTP_HEARTBEAT_SUCCESS);
735
736 /* The receiver of the HEARTBEAT ACK should also perform an
737 * RTT measurement for that destination transport address
738 * using the time value carried in the HEARTBEAT ACK chunk.
739 * If the transport's rto_pending variable has been cleared,
740 * it was most likely due to a retransmit. However, we want
741 * to re-enable it to properly update the rto.
742 */
743 if (t->rto_pending == 0)
744 t->rto_pending = 1;
745
746 hbinfo = (sctp_sender_hb_info_t *) chunk->skb->data;
747 sctp_transport_update_rto(t, (jiffies - hbinfo->sent_at));
748
749 /* Update the heartbeat timer. */
750 if (!mod_timer(&t->hb_timer, sctp_transport_timeout(t)))
751 sctp_transport_hold(t);
752
753 if (was_unconfirmed && asoc->peer.transport_count == 1)
754 sctp_transport_immediate_rtx(t);
755 }
756
757
758 /* Helper function to process the process SACK command. */
759 static int sctp_cmd_process_sack(sctp_cmd_seq_t *cmds,
760 struct sctp_association *asoc,
761 struct sctp_chunk *chunk)
762 {
763 int err = 0;
764
765 if (sctp_outq_sack(&asoc->outqueue, chunk)) {
766 struct net *net = sock_net(asoc->base.sk);
767
768 /* There are no more TSNs awaiting SACK. */
769 err = sctp_do_sm(net, SCTP_EVENT_T_OTHER,
770 SCTP_ST_OTHER(SCTP_EVENT_NO_PENDING_TSN),
771 asoc->state, asoc->ep, asoc, NULL,
772 GFP_ATOMIC);
773 }
774
775 return err;
776 }
777
778 /* Helper function to set the timeout value for T2-SHUTDOWN timer and to set
779 * the transport for a shutdown chunk.
780 */
781 static void sctp_cmd_setup_t2(sctp_cmd_seq_t *cmds,
782 struct sctp_association *asoc,
783 struct sctp_chunk *chunk)
784 {
785 struct sctp_transport *t;
786
787 if (chunk->transport)
788 t = chunk->transport;
789 else {
790 t = sctp_assoc_choose_alter_transport(asoc,
791 asoc->shutdown_last_sent_to);
792 chunk->transport = t;
793 }
794 asoc->shutdown_last_sent_to = t;
795 asoc->timeouts[SCTP_EVENT_TIMEOUT_T2_SHUTDOWN] = t->rto;
796 }
797
798 /* Helper function to change the state of an association. */
799 static void sctp_cmd_new_state(sctp_cmd_seq_t *cmds,
800 struct sctp_association *asoc,
801 sctp_state_t state)
802 {
803 struct sock *sk = asoc->base.sk;
804
805 asoc->state = state;
806
807 SCTP_DEBUG_PRINTK("sctp_cmd_new_state: asoc %p[%s]\n",
808 asoc, sctp_state_tbl[state]);
809
810 if (sctp_style(sk, TCP)) {
811 /* Change the sk->sk_state of a TCP-style socket that has
812 * successfully completed a connect() call.
813 */
814 if (sctp_state(asoc, ESTABLISHED) && sctp_sstate(sk, CLOSED))
815 sk->sk_state = SCTP_SS_ESTABLISHED;
816
817 /* Set the RCV_SHUTDOWN flag when a SHUTDOWN is received. */
818 if (sctp_state(asoc, SHUTDOWN_RECEIVED) &&
819 sctp_sstate(sk, ESTABLISHED))
820 sk->sk_shutdown |= RCV_SHUTDOWN;
821 }
822
823 if (sctp_state(asoc, COOKIE_WAIT)) {
824 /* Reset init timeouts since they may have been
825 * increased due to timer expirations.
826 */
827 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_INIT] =
828 asoc->rto_initial;
829 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_COOKIE] =
830 asoc->rto_initial;
831 }
832
833 if (sctp_state(asoc, ESTABLISHED) ||
834 sctp_state(asoc, CLOSED) ||
835 sctp_state(asoc, SHUTDOWN_RECEIVED)) {
836 /* Wake up any processes waiting in the asoc's wait queue in
837 * sctp_wait_for_connect() or sctp_wait_for_sndbuf().
838 */
839 if (waitqueue_active(&asoc->wait))
840 wake_up_interruptible(&asoc->wait);
841
842 /* Wake up any processes waiting in the sk's sleep queue of
843 * a TCP-style or UDP-style peeled-off socket in
844 * sctp_wait_for_accept() or sctp_wait_for_packet().
845 * For a UDP-style socket, the waiters are woken up by the
846 * notifications.
847 */
848 if (!sctp_style(sk, UDP))
849 sk->sk_state_change(sk);
850 }
851 }
852
853 /* Helper function to delete an association. */
854 static void sctp_cmd_delete_tcb(sctp_cmd_seq_t *cmds,
855 struct sctp_association *asoc)
856 {
857 struct sock *sk = asoc->base.sk;
858
859 /* If it is a non-temporary association belonging to a TCP-style
860 * listening socket that is not closed, do not free it so that accept()
861 * can pick it up later.
862 */
863 if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING) &&
864 (!asoc->temp) && (sk->sk_shutdown != SHUTDOWN_MASK))
865 return;
866
867 sctp_unhash_established(asoc);
868 sctp_association_free(asoc);
869 }
870
871 /*
872 * ADDIP Section 4.1 ASCONF Chunk Procedures
873 * A4) Start a T-4 RTO timer, using the RTO value of the selected
874 * destination address (we use active path instead of primary path just
875 * because primary path may be inactive.
876 */
877 static void sctp_cmd_setup_t4(sctp_cmd_seq_t *cmds,
878 struct sctp_association *asoc,
879 struct sctp_chunk *chunk)
880 {
881 struct sctp_transport *t;
882
883 t = sctp_assoc_choose_alter_transport(asoc, chunk->transport);
884 asoc->timeouts[SCTP_EVENT_TIMEOUT_T4_RTO] = t->rto;
885 chunk->transport = t;
886 }
887
888 /* Process an incoming Operation Error Chunk. */
889 static void sctp_cmd_process_operr(sctp_cmd_seq_t *cmds,
890 struct sctp_association *asoc,
891 struct sctp_chunk *chunk)
892 {
893 struct sctp_errhdr *err_hdr;
894 struct sctp_ulpevent *ev;
895
896 while (chunk->chunk_end > chunk->skb->data) {
897 err_hdr = (struct sctp_errhdr *)(chunk->skb->data);
898
899 ev = sctp_ulpevent_make_remote_error(asoc, chunk, 0,
900 GFP_ATOMIC);
901 if (!ev)
902 return;
903
904 sctp_ulpq_tail_event(&asoc->ulpq, ev);
905
906 switch (err_hdr->cause) {
907 case SCTP_ERROR_UNKNOWN_CHUNK:
908 {
909 sctp_chunkhdr_t *unk_chunk_hdr;
910
911 unk_chunk_hdr = (sctp_chunkhdr_t *)err_hdr->variable;
912 switch (unk_chunk_hdr->type) {
913 /* ADDIP 4.1 A9) If the peer responds to an ASCONF with
914 * an ERROR chunk reporting that it did not recognized
915 * the ASCONF chunk type, the sender of the ASCONF MUST
916 * NOT send any further ASCONF chunks and MUST stop its
917 * T-4 timer.
918 */
919 case SCTP_CID_ASCONF:
920 if (asoc->peer.asconf_capable == 0)
921 break;
922
923 asoc->peer.asconf_capable = 0;
924 sctp_add_cmd_sf(cmds, SCTP_CMD_TIMER_STOP,
925 SCTP_TO(SCTP_EVENT_TIMEOUT_T4_RTO));
926 break;
927 default:
928 break;
929 }
930 break;
931 }
932 default:
933 break;
934 }
935 }
936 }
937
938 /* Process variable FWDTSN chunk information. */
939 static void sctp_cmd_process_fwdtsn(struct sctp_ulpq *ulpq,
940 struct sctp_chunk *chunk)
941 {
942 struct sctp_fwdtsn_skip *skip;
943 /* Walk through all the skipped SSNs */
944 sctp_walk_fwdtsn(skip, chunk) {
945 sctp_ulpq_skip(ulpq, ntohs(skip->stream), ntohs(skip->ssn));
946 }
947 }
948
949 /* Helper function to remove the association non-primary peer
950 * transports.
951 */
952 static void sctp_cmd_del_non_primary(struct sctp_association *asoc)
953 {
954 struct sctp_transport *t;
955 struct list_head *pos;
956 struct list_head *temp;
957
958 list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
959 t = list_entry(pos, struct sctp_transport, transports);
960 if (!sctp_cmp_addr_exact(&t->ipaddr,
961 &asoc->peer.primary_addr)) {
962 sctp_assoc_del_peer(asoc, &t->ipaddr);
963 }
964 }
965 }
966
967 /* Helper function to set sk_err on a 1-1 style socket. */
968 static void sctp_cmd_set_sk_err(struct sctp_association *asoc, int error)
969 {
970 struct sock *sk = asoc->base.sk;
971
972 if (!sctp_style(sk, UDP))
973 sk->sk_err = error;
974 }
975
976 /* Helper function to generate an association change event */
977 static void sctp_cmd_assoc_change(sctp_cmd_seq_t *commands,
978 struct sctp_association *asoc,
979 u8 state)
980 {
981 struct sctp_ulpevent *ev;
982
983 ev = sctp_ulpevent_make_assoc_change(asoc, 0, state, 0,
984 asoc->c.sinit_num_ostreams,
985 asoc->c.sinit_max_instreams,
986 NULL, GFP_ATOMIC);
987 if (ev)
988 sctp_ulpq_tail_event(&asoc->ulpq, ev);
989 }
990
991 /* Helper function to generate an adaptation indication event */
992 static void sctp_cmd_adaptation_ind(sctp_cmd_seq_t *commands,
993 struct sctp_association *asoc)
994 {
995 struct sctp_ulpevent *ev;
996
997 ev = sctp_ulpevent_make_adaptation_indication(asoc, GFP_ATOMIC);
998
999 if (ev)
1000 sctp_ulpq_tail_event(&asoc->ulpq, ev);
1001 }
1002
1003
1004 static void sctp_cmd_t1_timer_update(struct sctp_association *asoc,
1005 sctp_event_timeout_t timer,
1006 char *name)
1007 {
1008 struct sctp_transport *t;
1009
1010 t = asoc->init_last_sent_to;
1011 asoc->init_err_counter++;
1012
1013 if (t->init_sent_count > (asoc->init_cycle + 1)) {
1014 asoc->timeouts[timer] *= 2;
1015 if (asoc->timeouts[timer] > asoc->max_init_timeo) {
1016 asoc->timeouts[timer] = asoc->max_init_timeo;
1017 }
1018 asoc->init_cycle++;
1019 SCTP_DEBUG_PRINTK(
1020 "T1 %s Timeout adjustment"
1021 " init_err_counter: %d"
1022 " cycle: %d"
1023 " timeout: %ld\n",
1024 name,
1025 asoc->init_err_counter,
1026 asoc->init_cycle,
1027 asoc->timeouts[timer]);
1028 }
1029
1030 }
1031
1032 /* Send the whole message, chunk by chunk, to the outqueue.
1033 * This way the whole message is queued up and bundling if
1034 * encouraged for small fragments.
1035 */
1036 static int sctp_cmd_send_msg(struct sctp_association *asoc,
1037 struct sctp_datamsg *msg)
1038 {
1039 struct sctp_chunk *chunk;
1040 int error = 0;
1041
1042 list_for_each_entry(chunk, &msg->chunks, frag_list) {
1043 error = sctp_outq_tail(&asoc->outqueue, chunk);
1044 if (error)
1045 break;
1046 }
1047
1048 return error;
1049 }
1050
1051
1052 /* Sent the next ASCONF packet currently stored in the association.
1053 * This happens after the ASCONF_ACK was succeffully processed.
1054 */
1055 static void sctp_cmd_send_asconf(struct sctp_association *asoc)
1056 {
1057 struct net *net = sock_net(asoc->base.sk);
1058
1059 /* Send the next asconf chunk from the addip chunk
1060 * queue.
1061 */
1062 if (!list_empty(&asoc->addip_chunk_list)) {
1063 struct list_head *entry = asoc->addip_chunk_list.next;
1064 struct sctp_chunk *asconf = list_entry(entry,
1065 struct sctp_chunk, list);
1066 list_del_init(entry);
1067
1068 /* Hold the chunk until an ASCONF_ACK is received. */
1069 sctp_chunk_hold(asconf);
1070 if (sctp_primitive_ASCONF(net, asoc, asconf))
1071 sctp_chunk_free(asconf);
1072 else
1073 asoc->addip_last_asconf = asconf;
1074 }
1075 }
1076
1077
1078 /* These three macros allow us to pull the debugging code out of the
1079 * main flow of sctp_do_sm() to keep attention focused on the real
1080 * functionality there.
1081 */
1082 #define DEBUG_PRE \
1083 SCTP_DEBUG_PRINTK("sctp_do_sm prefn: " \
1084 "ep %p, %s, %s, asoc %p[%s], %s\n", \
1085 ep, sctp_evttype_tbl[event_type], \
1086 (*debug_fn)(subtype), asoc, \
1087 sctp_state_tbl[state], state_fn->name)
1088
1089 #define DEBUG_POST \
1090 SCTP_DEBUG_PRINTK("sctp_do_sm postfn: " \
1091 "asoc %p, status: %s\n", \
1092 asoc, sctp_status_tbl[status])
1093
1094 #define DEBUG_POST_SFX \
1095 SCTP_DEBUG_PRINTK("sctp_do_sm post sfx: error %d, asoc %p[%s]\n", \
1096 error, asoc, \
1097 sctp_state_tbl[(asoc && sctp_id2assoc(ep->base.sk, \
1098 sctp_assoc2id(asoc)))?asoc->state:SCTP_STATE_CLOSED])
1099
1100 /*
1101 * This is the master state machine processing function.
1102 *
1103 * If you want to understand all of lksctp, this is a
1104 * good place to start.
1105 */
1106 int sctp_do_sm(struct net *net, sctp_event_t event_type, sctp_subtype_t subtype,
1107 sctp_state_t state,
1108 struct sctp_endpoint *ep,
1109 struct sctp_association *asoc,
1110 void *event_arg,
1111 gfp_t gfp)
1112 {
1113 sctp_cmd_seq_t commands;
1114 const sctp_sm_table_entry_t *state_fn;
1115 sctp_disposition_t status;
1116 int error = 0;
1117 typedef const char *(printfn_t)(sctp_subtype_t);
1118
1119 static printfn_t *table[] = {
1120 NULL, sctp_cname, sctp_tname, sctp_oname, sctp_pname,
1121 };
1122 printfn_t *debug_fn __attribute__ ((unused)) = table[event_type];
1123
1124 /* Look up the state function, run it, and then process the
1125 * side effects. These three steps are the heart of lksctp.
1126 */
1127 state_fn = sctp_sm_lookup_event(net, event_type, state, subtype);
1128
1129 sctp_init_cmd_seq(&commands);
1130
1131 DEBUG_PRE;
1132 status = (*state_fn->fn)(net, ep, asoc, subtype, event_arg, &commands);
1133 DEBUG_POST;
1134
1135 error = sctp_side_effects(event_type, subtype, state,
1136 ep, asoc, event_arg, status,
1137 &commands, gfp);
1138 DEBUG_POST_SFX;
1139
1140 return error;
1141 }
1142
1143 #undef DEBUG_PRE
1144 #undef DEBUG_POST
1145
1146 /*****************************************************************
1147 * This the master state function side effect processing function.
1148 *****************************************************************/
1149 static int sctp_side_effects(sctp_event_t event_type, sctp_subtype_t subtype,
1150 sctp_state_t state,
1151 struct sctp_endpoint *ep,
1152 struct sctp_association *asoc,
1153 void *event_arg,
1154 sctp_disposition_t status,
1155 sctp_cmd_seq_t *commands,
1156 gfp_t gfp)
1157 {
1158 int error;
1159
1160 /* FIXME - Most of the dispositions left today would be categorized
1161 * as "exceptional" dispositions. For those dispositions, it
1162 * may not be proper to run through any of the commands at all.
1163 * For example, the command interpreter might be run only with
1164 * disposition SCTP_DISPOSITION_CONSUME.
1165 */
1166 if (0 != (error = sctp_cmd_interpreter(event_type, subtype, state,
1167 ep, asoc,
1168 event_arg, status,
1169 commands, gfp)))
1170 goto bail;
1171
1172 switch (status) {
1173 case SCTP_DISPOSITION_DISCARD:
1174 SCTP_DEBUG_PRINTK("Ignored sctp protocol event - state %d, "
1175 "event_type %d, event_id %d\n",
1176 state, event_type, subtype.chunk);
1177 break;
1178
1179 case SCTP_DISPOSITION_NOMEM:
1180 /* We ran out of memory, so we need to discard this
1181 * packet.
1182 */
1183 /* BUG--we should now recover some memory, probably by
1184 * reneging...
1185 */
1186 error = -ENOMEM;
1187 break;
1188
1189 case SCTP_DISPOSITION_DELETE_TCB:
1190 /* This should now be a command. */
1191 break;
1192
1193 case SCTP_DISPOSITION_CONSUME:
1194 case SCTP_DISPOSITION_ABORT:
1195 /*
1196 * We should no longer have much work to do here as the
1197 * real work has been done as explicit commands above.
1198 */
1199 break;
1200
1201 case SCTP_DISPOSITION_VIOLATION:
1202 net_err_ratelimited("protocol violation state %d chunkid %d\n",
1203 state, subtype.chunk);
1204 break;
1205
1206 case SCTP_DISPOSITION_NOT_IMPL:
1207 pr_warn("unimplemented feature in state %d, event_type %d, event_id %d\n",
1208 state, event_type, subtype.chunk);
1209 break;
1210
1211 case SCTP_DISPOSITION_BUG:
1212 pr_err("bug in state %d, event_type %d, event_id %d\n",
1213 state, event_type, subtype.chunk);
1214 BUG();
1215 break;
1216
1217 default:
1218 pr_err("impossible disposition %d in state %d, event_type %d, event_id %d\n",
1219 status, state, event_type, subtype.chunk);
1220 BUG();
1221 break;
1222 }
1223
1224 bail:
1225 return error;
1226 }
1227
1228 /********************************************************************
1229 * 2nd Level Abstractions
1230 ********************************************************************/
1231
1232 /* This is the side-effect interpreter. */
1233 static int sctp_cmd_interpreter(sctp_event_t event_type,
1234 sctp_subtype_t subtype,
1235 sctp_state_t state,
1236 struct sctp_endpoint *ep,
1237 struct sctp_association *asoc,
1238 void *event_arg,
1239 sctp_disposition_t status,
1240 sctp_cmd_seq_t *commands,
1241 gfp_t gfp)
1242 {
1243 int error = 0;
1244 int force;
1245 sctp_cmd_t *cmd;
1246 struct sctp_chunk *new_obj;
1247 struct sctp_chunk *chunk = NULL;
1248 struct sctp_packet *packet;
1249 struct timer_list *timer;
1250 unsigned long timeout;
1251 struct sctp_transport *t;
1252 struct sctp_sackhdr sackh;
1253 int local_cork = 0;
1254
1255 if (SCTP_EVENT_T_TIMEOUT != event_type)
1256 chunk = event_arg;
1257
1258 /* Note: This whole file is a huge candidate for rework.
1259 * For example, each command could either have its own handler, so
1260 * the loop would look like:
1261 * while (cmds)
1262 * cmd->handle(x, y, z)
1263 * --jgrimm
1264 */
1265 while (NULL != (cmd = sctp_next_cmd(commands))) {
1266 switch (cmd->verb) {
1267 case SCTP_CMD_NOP:
1268 /* Do nothing. */
1269 break;
1270
1271 case SCTP_CMD_NEW_ASOC:
1272 /* Register a new association. */
1273 if (local_cork) {
1274 sctp_outq_uncork(&asoc->outqueue);
1275 local_cork = 0;
1276 }
1277 asoc = cmd->obj.asoc;
1278 /* Register with the endpoint. */
1279 sctp_endpoint_add_asoc(ep, asoc);
1280 sctp_hash_established(asoc);
1281 break;
1282
1283 case SCTP_CMD_UPDATE_ASSOC:
1284 sctp_assoc_update(asoc, cmd->obj.asoc);
1285 break;
1286
1287 case SCTP_CMD_PURGE_OUTQUEUE:
1288 sctp_outq_teardown(&asoc->outqueue);
1289 break;
1290
1291 case SCTP_CMD_DELETE_TCB:
1292 if (local_cork) {
1293 sctp_outq_uncork(&asoc->outqueue);
1294 local_cork = 0;
1295 }
1296 /* Delete the current association. */
1297 sctp_cmd_delete_tcb(commands, asoc);
1298 asoc = NULL;
1299 break;
1300
1301 case SCTP_CMD_NEW_STATE:
1302 /* Enter a new state. */
1303 sctp_cmd_new_state(commands, asoc, cmd->obj.state);
1304 break;
1305
1306 case SCTP_CMD_REPORT_TSN:
1307 /* Record the arrival of a TSN. */
1308 error = sctp_tsnmap_mark(&asoc->peer.tsn_map,
1309 cmd->obj.u32, NULL);
1310 break;
1311
1312 case SCTP_CMD_REPORT_FWDTSN:
1313 /* Move the Cumulattive TSN Ack ahead. */
1314 sctp_tsnmap_skip(&asoc->peer.tsn_map, cmd->obj.u32);
1315
1316 /* purge the fragmentation queue */
1317 sctp_ulpq_reasm_flushtsn(&asoc->ulpq, cmd->obj.u32);
1318
1319 /* Abort any in progress partial delivery. */
1320 sctp_ulpq_abort_pd(&asoc->ulpq, GFP_ATOMIC);
1321 break;
1322
1323 case SCTP_CMD_PROCESS_FWDTSN:
1324 sctp_cmd_process_fwdtsn(&asoc->ulpq, cmd->obj.chunk);
1325 break;
1326
1327 case SCTP_CMD_GEN_SACK:
1328 /* Generate a Selective ACK.
1329 * The argument tells us whether to just count
1330 * the packet and MAYBE generate a SACK, or
1331 * force a SACK out.
1332 */
1333 force = cmd->obj.i32;
1334 error = sctp_gen_sack(asoc, force, commands);
1335 break;
1336
1337 case SCTP_CMD_PROCESS_SACK:
1338 /* Process an inbound SACK. */
1339 error = sctp_cmd_process_sack(commands, asoc,
1340 cmd->obj.chunk);
1341 break;
1342
1343 case SCTP_CMD_GEN_INIT_ACK:
1344 /* Generate an INIT ACK chunk. */
1345 new_obj = sctp_make_init_ack(asoc, chunk, GFP_ATOMIC,
1346 0);
1347 if (!new_obj)
1348 goto nomem;
1349
1350 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
1351 SCTP_CHUNK(new_obj));
1352 break;
1353
1354 case SCTP_CMD_PEER_INIT:
1355 /* Process a unified INIT from the peer.
1356 * Note: Only used during INIT-ACK processing. If
1357 * there is an error just return to the outter
1358 * layer which will bail.
1359 */
1360 error = sctp_cmd_process_init(commands, asoc, chunk,
1361 cmd->obj.init, gfp);
1362 break;
1363
1364 case SCTP_CMD_GEN_COOKIE_ECHO:
1365 /* Generate a COOKIE ECHO chunk. */
1366 new_obj = sctp_make_cookie_echo(asoc, chunk);
1367 if (!new_obj) {
1368 if (cmd->obj.chunk)
1369 sctp_chunk_free(cmd->obj.chunk);
1370 goto nomem;
1371 }
1372 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
1373 SCTP_CHUNK(new_obj));
1374
1375 /* If there is an ERROR chunk to be sent along with
1376 * the COOKIE_ECHO, send it, too.
1377 */
1378 if (cmd->obj.chunk)
1379 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
1380 SCTP_CHUNK(cmd->obj.chunk));
1381
1382 if (new_obj->transport) {
1383 new_obj->transport->init_sent_count++;
1384 asoc->init_last_sent_to = new_obj->transport;
1385 }
1386
1387 /* FIXME - Eventually come up with a cleaner way to
1388 * enabling COOKIE-ECHO + DATA bundling during
1389 * multihoming stale cookie scenarios, the following
1390 * command plays with asoc->peer.retran_path to
1391 * avoid the problem of sending the COOKIE-ECHO and
1392 * DATA in different paths, which could result
1393 * in the association being ABORTed if the DATA chunk
1394 * is processed first by the server. Checking the
1395 * init error counter simply causes this command
1396 * to be executed only during failed attempts of
1397 * association establishment.
1398 */
1399 if ((asoc->peer.retran_path !=
1400 asoc->peer.primary_path) &&
1401 (asoc->init_err_counter > 0)) {
1402 sctp_add_cmd_sf(commands,
1403 SCTP_CMD_FORCE_PRIM_RETRAN,
1404 SCTP_NULL());
1405 }
1406
1407 break;
1408
1409 case SCTP_CMD_GEN_SHUTDOWN:
1410 /* Generate SHUTDOWN when in SHUTDOWN_SENT state.
1411 * Reset error counts.
1412 */
1413 asoc->overall_error_count = 0;
1414
1415 /* Generate a SHUTDOWN chunk. */
1416 new_obj = sctp_make_shutdown(asoc, chunk);
1417 if (!new_obj)
1418 goto nomem;
1419 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
1420 SCTP_CHUNK(new_obj));
1421 break;
1422
1423 case SCTP_CMD_CHUNK_ULP:
1424 /* Send a chunk to the sockets layer. */
1425 SCTP_DEBUG_PRINTK("sm_sideff: %s %p, %s %p.\n",
1426 "chunk_up:", cmd->obj.chunk,
1427 "ulpq:", &asoc->ulpq);
1428 sctp_ulpq_tail_data(&asoc->ulpq, cmd->obj.chunk,
1429 GFP_ATOMIC);
1430 break;
1431
1432 case SCTP_CMD_EVENT_ULP:
1433 /* Send a notification to the sockets layer. */
1434 SCTP_DEBUG_PRINTK("sm_sideff: %s %p, %s %p.\n",
1435 "event_up:",cmd->obj.ulpevent,
1436 "ulpq:",&asoc->ulpq);
1437 sctp_ulpq_tail_event(&asoc->ulpq, cmd->obj.ulpevent);
1438 break;
1439
1440 case SCTP_CMD_REPLY:
1441 /* If an caller has not already corked, do cork. */
1442 if (!asoc->outqueue.cork) {
1443 sctp_outq_cork(&asoc->outqueue);
1444 local_cork = 1;
1445 }
1446 /* Send a chunk to our peer. */
1447 error = sctp_outq_tail(&asoc->outqueue, cmd->obj.chunk);
1448 break;
1449
1450 case SCTP_CMD_SEND_PKT:
1451 /* Send a full packet to our peer. */
1452 packet = cmd->obj.packet;
1453 sctp_packet_transmit(packet);
1454 sctp_ootb_pkt_free(packet);
1455 break;
1456
1457 case SCTP_CMD_T1_RETRAN:
1458 /* Mark a transport for retransmission. */
1459 sctp_retransmit(&asoc->outqueue, cmd->obj.transport,
1460 SCTP_RTXR_T1_RTX);
1461 break;
1462
1463 case SCTP_CMD_RETRAN:
1464 /* Mark a transport for retransmission. */
1465 sctp_retransmit(&asoc->outqueue, cmd->obj.transport,
1466 SCTP_RTXR_T3_RTX);
1467 break;
1468
1469 case SCTP_CMD_ECN_CE:
1470 /* Do delayed CE processing. */
1471 sctp_do_ecn_ce_work(asoc, cmd->obj.u32);
1472 break;
1473
1474 case SCTP_CMD_ECN_ECNE:
1475 /* Do delayed ECNE processing. */
1476 new_obj = sctp_do_ecn_ecne_work(asoc, cmd->obj.u32,
1477 chunk);
1478 if (new_obj)
1479 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
1480 SCTP_CHUNK(new_obj));
1481 break;
1482
1483 case SCTP_CMD_ECN_CWR:
1484 /* Do delayed CWR processing. */
1485 sctp_do_ecn_cwr_work(asoc, cmd->obj.u32);
1486 break;
1487
1488 case SCTP_CMD_SETUP_T2:
1489 sctp_cmd_setup_t2(commands, asoc, cmd->obj.chunk);
1490 break;
1491
1492 case SCTP_CMD_TIMER_START_ONCE:
1493 timer = &asoc->timers[cmd->obj.to];
1494
1495 if (timer_pending(timer))
1496 break;
1497 /* fall through */
1498
1499 case SCTP_CMD_TIMER_START:
1500 timer = &asoc->timers[cmd->obj.to];
1501 timeout = asoc->timeouts[cmd->obj.to];
1502 BUG_ON(!timeout);
1503
1504 timer->expires = jiffies + timeout;
1505 sctp_association_hold(asoc);
1506 add_timer(timer);
1507 break;
1508
1509 case SCTP_CMD_TIMER_RESTART:
1510 timer = &asoc->timers[cmd->obj.to];
1511 timeout = asoc->timeouts[cmd->obj.to];
1512 if (!mod_timer(timer, jiffies + timeout))
1513 sctp_association_hold(asoc);
1514 break;
1515
1516 case SCTP_CMD_TIMER_STOP:
1517 timer = &asoc->timers[cmd->obj.to];
1518 if (del_timer(timer))
1519 sctp_association_put(asoc);
1520 break;
1521
1522 case SCTP_CMD_INIT_CHOOSE_TRANSPORT:
1523 chunk = cmd->obj.chunk;
1524 t = sctp_assoc_choose_alter_transport(asoc,
1525 asoc->init_last_sent_to);
1526 asoc->init_last_sent_to = t;
1527 chunk->transport = t;
1528 t->init_sent_count++;
1529 /* Set the new transport as primary */
1530 sctp_assoc_set_primary(asoc, t);
1531 break;
1532
1533 case SCTP_CMD_INIT_RESTART:
1534 /* Do the needed accounting and updates
1535 * associated with restarting an initialization
1536 * timer. Only multiply the timeout by two if
1537 * all transports have been tried at the current
1538 * timeout.
1539 */
1540 sctp_cmd_t1_timer_update(asoc,
1541 SCTP_EVENT_TIMEOUT_T1_INIT,
1542 "INIT");
1543
1544 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART,
1545 SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT));
1546 break;
1547
1548 case SCTP_CMD_COOKIEECHO_RESTART:
1549 /* Do the needed accounting and updates
1550 * associated with restarting an initialization
1551 * timer. Only multiply the timeout by two if
1552 * all transports have been tried at the current
1553 * timeout.
1554 */
1555 sctp_cmd_t1_timer_update(asoc,
1556 SCTP_EVENT_TIMEOUT_T1_COOKIE,
1557 "COOKIE");
1558
1559 /* If we've sent any data bundled with
1560 * COOKIE-ECHO we need to resend.
1561 */
1562 list_for_each_entry(t, &asoc->peer.transport_addr_list,
1563 transports) {
1564 sctp_retransmit_mark(&asoc->outqueue, t,
1565 SCTP_RTXR_T1_RTX);
1566 }
1567
1568 sctp_add_cmd_sf(commands,
1569 SCTP_CMD_TIMER_RESTART,
1570 SCTP_TO(SCTP_EVENT_TIMEOUT_T1_COOKIE));
1571 break;
1572
1573 case SCTP_CMD_INIT_FAILED:
1574 sctp_cmd_init_failed(commands, asoc, cmd->obj.err);
1575 break;
1576
1577 case SCTP_CMD_ASSOC_FAILED:
1578 sctp_cmd_assoc_failed(commands, asoc, event_type,
1579 subtype, chunk, cmd->obj.err);
1580 break;
1581
1582 case SCTP_CMD_INIT_COUNTER_INC:
1583 asoc->init_err_counter++;
1584 break;
1585
1586 case SCTP_CMD_INIT_COUNTER_RESET:
1587 asoc->init_err_counter = 0;
1588 asoc->init_cycle = 0;
1589 list_for_each_entry(t, &asoc->peer.transport_addr_list,
1590 transports) {
1591 t->init_sent_count = 0;
1592 }
1593 break;
1594
1595 case SCTP_CMD_REPORT_DUP:
1596 sctp_tsnmap_mark_dup(&asoc->peer.tsn_map,
1597 cmd->obj.u32);
1598 break;
1599
1600 case SCTP_CMD_REPORT_BAD_TAG:
1601 SCTP_DEBUG_PRINTK("vtag mismatch!\n");
1602 break;
1603
1604 case SCTP_CMD_STRIKE:
1605 /* Mark one strike against a transport. */
1606 sctp_do_8_2_transport_strike(commands, asoc,
1607 cmd->obj.transport, 0);
1608 break;
1609
1610 case SCTP_CMD_TRANSPORT_IDLE:
1611 t = cmd->obj.transport;
1612 sctp_transport_lower_cwnd(t, SCTP_LOWER_CWND_INACTIVE);
1613 break;
1614
1615 case SCTP_CMD_TRANSPORT_HB_SENT:
1616 t = cmd->obj.transport;
1617 sctp_do_8_2_transport_strike(commands, asoc,
1618 t, 1);
1619 t->hb_sent = 1;
1620 break;
1621
1622 case SCTP_CMD_TRANSPORT_ON:
1623 t = cmd->obj.transport;
1624 sctp_cmd_transport_on(commands, asoc, t, chunk);
1625 break;
1626
1627 case SCTP_CMD_HB_TIMERS_START:
1628 sctp_cmd_hb_timers_start(commands, asoc);
1629 break;
1630
1631 case SCTP_CMD_HB_TIMER_UPDATE:
1632 t = cmd->obj.transport;
1633 sctp_cmd_hb_timer_update(commands, t);
1634 break;
1635
1636 case SCTP_CMD_HB_TIMERS_STOP:
1637 sctp_cmd_hb_timers_stop(commands, asoc);
1638 break;
1639
1640 case SCTP_CMD_REPORT_ERROR:
1641 error = cmd->obj.error;
1642 break;
1643
1644 case SCTP_CMD_PROCESS_CTSN:
1645 /* Dummy up a SACK for processing. */
1646 sackh.cum_tsn_ack = cmd->obj.be32;
1647 sackh.a_rwnd = asoc->peer.rwnd +
1648 asoc->outqueue.outstanding_bytes;
1649 sackh.num_gap_ack_blocks = 0;
1650 sackh.num_dup_tsns = 0;
1651 chunk->subh.sack_hdr = &sackh;
1652 sctp_add_cmd_sf(commands, SCTP_CMD_PROCESS_SACK,
1653 SCTP_CHUNK(chunk));
1654 break;
1655
1656 case SCTP_CMD_DISCARD_PACKET:
1657 /* We need to discard the whole packet.
1658 * Uncork the queue since there might be
1659 * responses pending
1660 */
1661 chunk->pdiscard = 1;
1662 if (asoc) {
1663 sctp_outq_uncork(&asoc->outqueue);
1664 local_cork = 0;
1665 }
1666 break;
1667
1668 case SCTP_CMD_RTO_PENDING:
1669 t = cmd->obj.transport;
1670 t->rto_pending = 1;
1671 break;
1672
1673 case SCTP_CMD_PART_DELIVER:
1674 sctp_ulpq_partial_delivery(&asoc->ulpq, GFP_ATOMIC);
1675 break;
1676
1677 case SCTP_CMD_RENEGE:
1678 sctp_ulpq_renege(&asoc->ulpq, cmd->obj.chunk,
1679 GFP_ATOMIC);
1680 break;
1681
1682 case SCTP_CMD_SETUP_T4:
1683 sctp_cmd_setup_t4(commands, asoc, cmd->obj.chunk);
1684 break;
1685
1686 case SCTP_CMD_PROCESS_OPERR:
1687 sctp_cmd_process_operr(commands, asoc, chunk);
1688 break;
1689 case SCTP_CMD_CLEAR_INIT_TAG:
1690 asoc->peer.i.init_tag = 0;
1691 break;
1692 case SCTP_CMD_DEL_NON_PRIMARY:
1693 sctp_cmd_del_non_primary(asoc);
1694 break;
1695 case SCTP_CMD_T3_RTX_TIMERS_STOP:
1696 sctp_cmd_t3_rtx_timers_stop(commands, asoc);
1697 break;
1698 case SCTP_CMD_FORCE_PRIM_RETRAN:
1699 t = asoc->peer.retran_path;
1700 asoc->peer.retran_path = asoc->peer.primary_path;
1701 error = sctp_outq_uncork(&asoc->outqueue);
1702 local_cork = 0;
1703 asoc->peer.retran_path = t;
1704 break;
1705 case SCTP_CMD_SET_SK_ERR:
1706 sctp_cmd_set_sk_err(asoc, cmd->obj.error);
1707 break;
1708 case SCTP_CMD_ASSOC_CHANGE:
1709 sctp_cmd_assoc_change(commands, asoc,
1710 cmd->obj.u8);
1711 break;
1712 case SCTP_CMD_ADAPTATION_IND:
1713 sctp_cmd_adaptation_ind(commands, asoc);
1714 break;
1715
1716 case SCTP_CMD_ASSOC_SHKEY:
1717 error = sctp_auth_asoc_init_active_key(asoc,
1718 GFP_ATOMIC);
1719 break;
1720 case SCTP_CMD_UPDATE_INITTAG:
1721 asoc->peer.i.init_tag = cmd->obj.u32;
1722 break;
1723 case SCTP_CMD_SEND_MSG:
1724 if (!asoc->outqueue.cork) {
1725 sctp_outq_cork(&asoc->outqueue);
1726 local_cork = 1;
1727 }
1728 error = sctp_cmd_send_msg(asoc, cmd->obj.msg);
1729 break;
1730 case SCTP_CMD_SEND_NEXT_ASCONF:
1731 sctp_cmd_send_asconf(asoc);
1732 break;
1733 case SCTP_CMD_PURGE_ASCONF_QUEUE:
1734 sctp_asconf_queue_teardown(asoc);
1735 break;
1736
1737 case SCTP_CMD_SET_ASOC:
1738 asoc = cmd->obj.asoc;
1739 break;
1740
1741 default:
1742 pr_warn("Impossible command: %u\n",
1743 cmd->verb);
1744 break;
1745 }
1746
1747 if (error)
1748 break;
1749 }
1750
1751 out:
1752 /* If this is in response to a received chunk, wait until
1753 * we are done with the packet to open the queue so that we don't
1754 * send multiple packets in response to a single request.
1755 */
1756 if (asoc && SCTP_EVENT_T_CHUNK == event_type && chunk) {
1757 if (chunk->end_of_packet || chunk->singleton)
1758 error = sctp_outq_uncork(&asoc->outqueue);
1759 } else if (local_cork)
1760 error = sctp_outq_uncork(&asoc->outqueue);
1761 return error;
1762 nomem:
1763 error = -ENOMEM;
1764 goto out;
1765 }
1766
Linus' kernel tree