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ipv4: Prepare for change of rt->rt_iif encoding.
[deliverable/linux.git] / net / sctp / sm_sideeffect.c
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
255 /* Check whether a task is in the sock. */
256
257 sctp_bh_lock_sock(asoc->base.sk);
258 if (sock_owned_by_user(asoc->base.sk)) {
259 SCTP_DEBUG_PRINTK("%s:Sock is busy.\n", __func__);
260
261 /* Try again later. */
262 if (!mod_timer(&transport->T3_rtx_timer, jiffies + (HZ/20)))
263 sctp_transport_hold(transport);
264 goto out_unlock;
265 }
266
267 /* Is this transport really dead and just waiting around for
268 * the timer to let go of the reference?
269 */
270 if (transport->dead)
271 goto out_unlock;
272
273 /* Run through the state machine. */
274 error = sctp_do_sm(SCTP_EVENT_T_TIMEOUT,
275 SCTP_ST_TIMEOUT(SCTP_EVENT_TIMEOUT_T3_RTX),
276 asoc->state,
277 asoc->ep, asoc,
278 transport, GFP_ATOMIC);
279
280 if (error)
281 asoc->base.sk->sk_err = -error;
282
283 out_unlock:
284 sctp_bh_unlock_sock(asoc->base.sk);
285 sctp_transport_put(transport);
286 }
287
288 /* This is a sa interface for producing timeout events. It works
289 * for timeouts which use the association as their parameter.
290 */
291 static void sctp_generate_timeout_event(struct sctp_association *asoc,
292 sctp_event_timeout_t timeout_type)
293 {
294 int error = 0;
295
296 sctp_bh_lock_sock(asoc->base.sk);
297 if (sock_owned_by_user(asoc->base.sk)) {
298 SCTP_DEBUG_PRINTK("%s:Sock is busy: timer %d\n",
299 __func__,
300 timeout_type);
301
302 /* Try again later. */
303 if (!mod_timer(&asoc->timers[timeout_type], jiffies + (HZ/20)))
304 sctp_association_hold(asoc);
305 goto out_unlock;
306 }
307
308 /* Is this association really dead and just waiting around for
309 * the timer to let go of the reference?
310 */
311 if (asoc->base.dead)
312 goto out_unlock;
313
314 /* Run through the state machine. */
315 error = sctp_do_sm(SCTP_EVENT_T_TIMEOUT,
316 SCTP_ST_TIMEOUT(timeout_type),
317 asoc->state, asoc->ep, asoc,
318 (void *)timeout_type, GFP_ATOMIC);
319
320 if (error)
321 asoc->base.sk->sk_err = -error;
322
323 out_unlock:
324 sctp_bh_unlock_sock(asoc->base.sk);
325 sctp_association_put(asoc);
326 }
327
328 static void sctp_generate_t1_cookie_event(unsigned long data)
329 {
330 struct sctp_association *asoc = (struct sctp_association *) data;
331 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T1_COOKIE);
332 }
333
334 static void sctp_generate_t1_init_event(unsigned long data)
335 {
336 struct sctp_association *asoc = (struct sctp_association *) data;
337 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T1_INIT);
338 }
339
340 static void sctp_generate_t2_shutdown_event(unsigned long data)
341 {
342 struct sctp_association *asoc = (struct sctp_association *) data;
343 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T2_SHUTDOWN);
344 }
345
346 static void sctp_generate_t4_rto_event(unsigned long data)
347 {
348 struct sctp_association *asoc = (struct sctp_association *) data;
349 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T4_RTO);
350 }
351
352 static void sctp_generate_t5_shutdown_guard_event(unsigned long data)
353 {
354 struct sctp_association *asoc = (struct sctp_association *)data;
355 sctp_generate_timeout_event(asoc,
356 SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD);
357
358 } /* sctp_generate_t5_shutdown_guard_event() */
359
360 static void sctp_generate_autoclose_event(unsigned long data)
361 {
362 struct sctp_association *asoc = (struct sctp_association *) data;
363 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_AUTOCLOSE);
364 }
365
366 /* Generate a heart beat event. If the sock is busy, reschedule. Make
367 * sure that the transport is still valid.
368 */
369 void sctp_generate_heartbeat_event(unsigned long data)
370 {
371 int error = 0;
372 struct sctp_transport *transport = (struct sctp_transport *) data;
373 struct sctp_association *asoc = transport->asoc;
374
375 sctp_bh_lock_sock(asoc->base.sk);
376 if (sock_owned_by_user(asoc->base.sk)) {
377 SCTP_DEBUG_PRINTK("%s:Sock is busy.\n", __func__);
378
379 /* Try again later. */
380 if (!mod_timer(&transport->hb_timer, jiffies + (HZ/20)))
381 sctp_transport_hold(transport);
382 goto out_unlock;
383 }
384
385 /* Is this structure just waiting around for us to actually
386 * get destroyed?
387 */
388 if (transport->dead)
389 goto out_unlock;
390
391 error = sctp_do_sm(SCTP_EVENT_T_TIMEOUT,
392 SCTP_ST_TIMEOUT(SCTP_EVENT_TIMEOUT_HEARTBEAT),
393 asoc->state, asoc->ep, asoc,
394 transport, GFP_ATOMIC);
395
396 if (error)
397 asoc->base.sk->sk_err = -error;
398
399 out_unlock:
400 sctp_bh_unlock_sock(asoc->base.sk);
401 sctp_transport_put(transport);
402 }
403
404 /* Handle the timeout of the ICMP protocol unreachable timer. Trigger
405 * the correct state machine transition that will close the association.
406 */
407 void sctp_generate_proto_unreach_event(unsigned long data)
408 {
409 struct sctp_transport *transport = (struct sctp_transport *) data;
410 struct sctp_association *asoc = transport->asoc;
411
412 sctp_bh_lock_sock(asoc->base.sk);
413 if (sock_owned_by_user(asoc->base.sk)) {
414 SCTP_DEBUG_PRINTK("%s:Sock is busy.\n", __func__);
415
416 /* Try again later. */
417 if (!mod_timer(&transport->proto_unreach_timer,
418 jiffies + (HZ/20)))
419 sctp_association_hold(asoc);
420 goto out_unlock;
421 }
422
423 /* Is this structure just waiting around for us to actually
424 * get destroyed?
425 */
426 if (asoc->base.dead)
427 goto out_unlock;
428
429 sctp_do_sm(SCTP_EVENT_T_OTHER,
430 SCTP_ST_OTHER(SCTP_EVENT_ICMP_PROTO_UNREACH),
431 asoc->state, asoc->ep, asoc, transport, GFP_ATOMIC);
432
433 out_unlock:
434 sctp_bh_unlock_sock(asoc->base.sk);
435 sctp_association_put(asoc);
436 }
437
438
439 /* Inject a SACK Timeout event into the state machine. */
440 static void sctp_generate_sack_event(unsigned long data)
441 {
442 struct sctp_association *asoc = (struct sctp_association *) data;
443 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_SACK);
444 }
445
446 sctp_timer_event_t *sctp_timer_events[SCTP_NUM_TIMEOUT_TYPES] = {
447 NULL,
448 sctp_generate_t1_cookie_event,
449 sctp_generate_t1_init_event,
450 sctp_generate_t2_shutdown_event,
451 NULL,
452 sctp_generate_t4_rto_event,
453 sctp_generate_t5_shutdown_guard_event,
454 NULL,
455 sctp_generate_sack_event,
456 sctp_generate_autoclose_event,
457 };
458
459
460 /* RFC 2960 8.2 Path Failure Detection
461 *
462 * When its peer endpoint is multi-homed, an endpoint should keep a
463 * error counter for each of the destination transport addresses of the
464 * peer endpoint.
465 *
466 * Each time the T3-rtx timer expires on any address, or when a
467 * HEARTBEAT sent to an idle address is not acknowledged within a RTO,
468 * the error counter of that destination address will be incremented.
469 * When the value in the error counter exceeds the protocol parameter
470 * 'Path.Max.Retrans' of that destination address, the endpoint should
471 * mark the destination transport address as inactive, and a
472 * notification SHOULD be sent to the upper layer.
473 *
474 */
475 static void sctp_do_8_2_transport_strike(sctp_cmd_seq_t *commands,
476 struct sctp_association *asoc,
477 struct sctp_transport *transport,
478 int is_hb)
479 {
480 /* The check for association's overall error counter exceeding the
481 * threshold is done in the state function.
482 */
483 /* We are here due to a timer expiration. If the timer was
484 * not a HEARTBEAT, then normal error tracking is done.
485 * If the timer was a heartbeat, we only increment error counts
486 * when we already have an outstanding HEARTBEAT that has not
487 * been acknowledged.
488 * Additionally, some tranport states inhibit error increments.
489 */
490 if (!is_hb) {
491 asoc->overall_error_count++;
492 if (transport->state != SCTP_INACTIVE)
493 transport->error_count++;
494 } else if (transport->hb_sent) {
495 if (transport->state != SCTP_UNCONFIRMED)
496 asoc->overall_error_count++;
497 if (transport->state != SCTP_INACTIVE)
498 transport->error_count++;
499 }
500
501 /* If the transport error count is greater than the pf_retrans
502 * threshold, and less than pathmaxrtx, then mark this transport
503 * as Partially Failed, ee SCTP Quick Failover Draft, secon 5.1,
504 * point 1
505 */
506 if ((transport->state != SCTP_PF) &&
507 (asoc->pf_retrans < transport->pathmaxrxt) &&
508 (transport->error_count > asoc->pf_retrans)) {
509
510 sctp_assoc_control_transport(asoc, transport,
511 SCTP_TRANSPORT_PF,
512 0);
513
514 /* Update the hb timer to resend a heartbeat every rto */
515 sctp_cmd_hb_timer_update(commands, transport);
516 }
517
518 if (transport->state != SCTP_INACTIVE &&
519 (transport->error_count > transport->pathmaxrxt)) {
520 SCTP_DEBUG_PRINTK_IPADDR("transport_strike:association %p",
521 " transport IP: port:%d failed.\n",
522 asoc,
523 (&transport->ipaddr),
524 ntohs(transport->ipaddr.v4.sin_port));
525 sctp_assoc_control_transport(asoc, transport,
526 SCTP_TRANSPORT_DOWN,
527 SCTP_FAILED_THRESHOLD);
528 }
529
530 /* E2) For the destination address for which the timer
531 * expires, set RTO <- RTO * 2 ("back off the timer"). The
532 * maximum value discussed in rule C7 above (RTO.max) may be
533 * used to provide an upper bound to this doubling operation.
534 *
535 * Special Case: the first HB doesn't trigger exponential backoff.
536 * The first unacknowledged HB triggers it. We do this with a flag
537 * that indicates that we have an outstanding HB.
538 */
539 if (!is_hb || transport->hb_sent) {
540 transport->rto = min((transport->rto * 2), transport->asoc->rto_max);
541 }
542 }
543
544 /* Worker routine to handle INIT command failure. */
545 static void sctp_cmd_init_failed(sctp_cmd_seq_t *commands,
546 struct sctp_association *asoc,
547 unsigned int error)
548 {
549 struct sctp_ulpevent *event;
550
551 event = sctp_ulpevent_make_assoc_change(asoc,0, SCTP_CANT_STR_ASSOC,
552 (__u16)error, 0, 0, NULL,
553 GFP_ATOMIC);
554
555 if (event)
556 sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP,
557 SCTP_ULPEVENT(event));
558
559 sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE,
560 SCTP_STATE(SCTP_STATE_CLOSED));
561
562 /* SEND_FAILED sent later when cleaning up the association. */
563 asoc->outqueue.error = error;
564 sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL());
565 }
566
567 /* Worker routine to handle SCTP_CMD_ASSOC_FAILED. */
568 static void sctp_cmd_assoc_failed(sctp_cmd_seq_t *commands,
569 struct sctp_association *asoc,
570 sctp_event_t event_type,
571 sctp_subtype_t subtype,
572 struct sctp_chunk *chunk,
573 unsigned int error)
574 {
575 struct sctp_ulpevent *event;
576
577 /* Cancel any partial delivery in progress. */
578 sctp_ulpq_abort_pd(&asoc->ulpq, GFP_ATOMIC);
579
580 if (event_type == SCTP_EVENT_T_CHUNK && subtype.chunk == SCTP_CID_ABORT)
581 event = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_COMM_LOST,
582 (__u16)error, 0, 0, chunk,
583 GFP_ATOMIC);
584 else
585 event = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_COMM_LOST,
586 (__u16)error, 0, 0, NULL,
587 GFP_ATOMIC);
588 if (event)
589 sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP,
590 SCTP_ULPEVENT(event));
591
592 sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE,
593 SCTP_STATE(SCTP_STATE_CLOSED));
594
595 /* SEND_FAILED sent later when cleaning up the association. */
596 asoc->outqueue.error = error;
597 sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL());
598 }
599
600 /* Process an init chunk (may be real INIT/INIT-ACK or an embedded INIT
601 * inside the cookie. In reality, this is only used for INIT-ACK processing
602 * since all other cases use "temporary" associations and can do all
603 * their work in statefuns directly.
604 */
605 static int sctp_cmd_process_init(sctp_cmd_seq_t *commands,
606 struct sctp_association *asoc,
607 struct sctp_chunk *chunk,
608 sctp_init_chunk_t *peer_init,
609 gfp_t gfp)
610 {
611 int error;
612
613 /* We only process the init as a sideeffect in a single
614 * case. This is when we process the INIT-ACK. If we
615 * fail during INIT processing (due to malloc problems),
616 * just return the error and stop processing the stack.
617 */
618 if (!sctp_process_init(asoc, chunk, sctp_source(chunk), peer_init, gfp))
619 error = -ENOMEM;
620 else
621 error = 0;
622
623 return error;
624 }
625
626 /* Helper function to break out starting up of heartbeat timers. */
627 static void sctp_cmd_hb_timers_start(sctp_cmd_seq_t *cmds,
628 struct sctp_association *asoc)
629 {
630 struct sctp_transport *t;
631
632 /* Start a heartbeat timer for each transport on the association.
633 * hold a reference on the transport to make sure none of
634 * the needed data structures go away.
635 */
636 list_for_each_entry(t, &asoc->peer.transport_addr_list, transports) {
637
638 if (!mod_timer(&t->hb_timer, sctp_transport_timeout(t)))
639 sctp_transport_hold(t);
640 }
641 }
642
643 static void sctp_cmd_hb_timers_stop(sctp_cmd_seq_t *cmds,
644 struct sctp_association *asoc)
645 {
646 struct sctp_transport *t;
647
648 /* Stop all heartbeat timers. */
649
650 list_for_each_entry(t, &asoc->peer.transport_addr_list,
651 transports) {
652 if (del_timer(&t->hb_timer))
653 sctp_transport_put(t);
654 }
655 }
656
657 /* Helper function to stop any pending T3-RTX timers */
658 static void sctp_cmd_t3_rtx_timers_stop(sctp_cmd_seq_t *cmds,
659 struct sctp_association *asoc)
660 {
661 struct sctp_transport *t;
662
663 list_for_each_entry(t, &asoc->peer.transport_addr_list,
664 transports) {
665 if (timer_pending(&t->T3_rtx_timer) &&
666 del_timer(&t->T3_rtx_timer)) {
667 sctp_transport_put(t);
668 }
669 }
670 }
671
672
673 /* Helper function to update the heartbeat timer. */
674 static void sctp_cmd_hb_timer_update(sctp_cmd_seq_t *cmds,
675 struct sctp_transport *t)
676 {
677 /* Update the heartbeat timer. */
678 if (!mod_timer(&t->hb_timer, sctp_transport_timeout(t)))
679 sctp_transport_hold(t);
680 }
681
682 /* Helper function to handle the reception of an HEARTBEAT ACK. */
683 static void sctp_cmd_transport_on(sctp_cmd_seq_t *cmds,
684 struct sctp_association *asoc,
685 struct sctp_transport *t,
686 struct sctp_chunk *chunk)
687 {
688 sctp_sender_hb_info_t *hbinfo;
689 int was_unconfirmed = 0;
690
691 /* 8.3 Upon the receipt of the HEARTBEAT ACK, the sender of the
692 * HEARTBEAT should clear the error counter of the destination
693 * transport address to which the HEARTBEAT was sent.
694 */
695 t->error_count = 0;
696
697 /*
698 * Although RFC4960 specifies that the overall error count must
699 * be cleared when a HEARTBEAT ACK is received, we make an
700 * exception while in SHUTDOWN PENDING. If the peer keeps its
701 * window shut forever, we may never be able to transmit our
702 * outstanding data and rely on the retransmission limit be reached
703 * to shutdown the association.
704 */
705 if (t->asoc->state != SCTP_STATE_SHUTDOWN_PENDING)
706 t->asoc->overall_error_count = 0;
707
708 /* Clear the hb_sent flag to signal that we had a good
709 * acknowledgement.
710 */
711 t->hb_sent = 0;
712
713 /* Mark the destination transport address as active if it is not so
714 * marked.
715 */
716 if ((t->state == SCTP_INACTIVE) || (t->state == SCTP_UNCONFIRMED)) {
717 was_unconfirmed = 1;
718 sctp_assoc_control_transport(asoc, t, SCTP_TRANSPORT_UP,
719 SCTP_HEARTBEAT_SUCCESS);
720 }
721
722 if (t->state == SCTP_PF)
723 sctp_assoc_control_transport(asoc, t, SCTP_TRANSPORT_UP,
724 SCTP_HEARTBEAT_SUCCESS);
725
726 /* The receiver of the HEARTBEAT ACK should also perform an
727 * RTT measurement for that destination transport address
728 * using the time value carried in the HEARTBEAT ACK chunk.
729 * If the transport's rto_pending variable has been cleared,
730 * it was most likely due to a retransmit. However, we want
731 * to re-enable it to properly update the rto.
732 */
733 if (t->rto_pending == 0)
734 t->rto_pending = 1;
735
736 hbinfo = (sctp_sender_hb_info_t *) chunk->skb->data;
737 sctp_transport_update_rto(t, (jiffies - hbinfo->sent_at));
738
739 /* Update the heartbeat timer. */
740 if (!mod_timer(&t->hb_timer, sctp_transport_timeout(t)))
741 sctp_transport_hold(t);
742
743 if (was_unconfirmed && asoc->peer.transport_count == 1)
744 sctp_transport_immediate_rtx(t);
745 }
746
747
748 /* Helper function to process the process SACK command. */
749 static int sctp_cmd_process_sack(sctp_cmd_seq_t *cmds,
750 struct sctp_association *asoc,
751 struct sctp_sackhdr *sackh)
752 {
753 int err = 0;
754
755 if (sctp_outq_sack(&asoc->outqueue, sackh)) {
756 /* There are no more TSNs awaiting SACK. */
757 err = sctp_do_sm(SCTP_EVENT_T_OTHER,
758 SCTP_ST_OTHER(SCTP_EVENT_NO_PENDING_TSN),
759 asoc->state, asoc->ep, asoc, NULL,
760 GFP_ATOMIC);
761 }
762
763 return err;
764 }
765
766 /* Helper function to set the timeout value for T2-SHUTDOWN timer and to set
767 * the transport for a shutdown chunk.
768 */
769 static void sctp_cmd_setup_t2(sctp_cmd_seq_t *cmds,
770 struct sctp_association *asoc,
771 struct sctp_chunk *chunk)
772 {
773 struct sctp_transport *t;
774
775 if (chunk->transport)
776 t = chunk->transport;
777 else {
778 t = sctp_assoc_choose_alter_transport(asoc,
779 asoc->shutdown_last_sent_to);
780 chunk->transport = t;
781 }
782 asoc->shutdown_last_sent_to = t;
783 asoc->timeouts[SCTP_EVENT_TIMEOUT_T2_SHUTDOWN] = t->rto;
784 }
785
786 /* Helper function to change the state of an association. */
787 static void sctp_cmd_new_state(sctp_cmd_seq_t *cmds,
788 struct sctp_association *asoc,
789 sctp_state_t state)
790 {
791 struct sock *sk = asoc->base.sk;
792
793 asoc->state = state;
794
795 SCTP_DEBUG_PRINTK("sctp_cmd_new_state: asoc %p[%s]\n",
796 asoc, sctp_state_tbl[state]);
797
798 if (sctp_style(sk, TCP)) {
799 /* Change the sk->sk_state of a TCP-style socket that has
800 * successfully completed a connect() call.
801 */
802 if (sctp_state(asoc, ESTABLISHED) && sctp_sstate(sk, CLOSED))
803 sk->sk_state = SCTP_SS_ESTABLISHED;
804
805 /* Set the RCV_SHUTDOWN flag when a SHUTDOWN is received. */
806 if (sctp_state(asoc, SHUTDOWN_RECEIVED) &&
807 sctp_sstate(sk, ESTABLISHED))
808 sk->sk_shutdown |= RCV_SHUTDOWN;
809 }
810
811 if (sctp_state(asoc, COOKIE_WAIT)) {
812 /* Reset init timeouts since they may have been
813 * increased due to timer expirations.
814 */
815 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_INIT] =
816 asoc->rto_initial;
817 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_COOKIE] =
818 asoc->rto_initial;
819 }
820
821 if (sctp_state(asoc, ESTABLISHED) ||
822 sctp_state(asoc, CLOSED) ||
823 sctp_state(asoc, SHUTDOWN_RECEIVED)) {
824 /* Wake up any processes waiting in the asoc's wait queue in
825 * sctp_wait_for_connect() or sctp_wait_for_sndbuf().
826 */
827 if (waitqueue_active(&asoc->wait))
828 wake_up_interruptible(&asoc->wait);
829
830 /* Wake up any processes waiting in the sk's sleep queue of
831 * a TCP-style or UDP-style peeled-off socket in
832 * sctp_wait_for_accept() or sctp_wait_for_packet().
833 * For a UDP-style socket, the waiters are woken up by the
834 * notifications.
835 */
836 if (!sctp_style(sk, UDP))
837 sk->sk_state_change(sk);
838 }
839 }
840
841 /* Helper function to delete an association. */
842 static void sctp_cmd_delete_tcb(sctp_cmd_seq_t *cmds,
843 struct sctp_association *asoc)
844 {
845 struct sock *sk = asoc->base.sk;
846
847 /* If it is a non-temporary association belonging to a TCP-style
848 * listening socket that is not closed, do not free it so that accept()
849 * can pick it up later.
850 */
851 if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING) &&
852 (!asoc->temp) && (sk->sk_shutdown != SHUTDOWN_MASK))
853 return;
854
855 sctp_unhash_established(asoc);
856 sctp_association_free(asoc);
857 }
858
859 /*
860 * ADDIP Section 4.1 ASCONF Chunk Procedures
861 * A4) Start a T-4 RTO timer, using the RTO value of the selected
862 * destination address (we use active path instead of primary path just
863 * because primary path may be inactive.
864 */
865 static void sctp_cmd_setup_t4(sctp_cmd_seq_t *cmds,
866 struct sctp_association *asoc,
867 struct sctp_chunk *chunk)
868 {
869 struct sctp_transport *t;
870
871 t = sctp_assoc_choose_alter_transport(asoc, chunk->transport);
872 asoc->timeouts[SCTP_EVENT_TIMEOUT_T4_RTO] = t->rto;
873 chunk->transport = t;
874 }
875
876 /* Process an incoming Operation Error Chunk. */
877 static void sctp_cmd_process_operr(sctp_cmd_seq_t *cmds,
878 struct sctp_association *asoc,
879 struct sctp_chunk *chunk)
880 {
881 struct sctp_errhdr *err_hdr;
882 struct sctp_ulpevent *ev;
883
884 while (chunk->chunk_end > chunk->skb->data) {
885 err_hdr = (struct sctp_errhdr *)(chunk->skb->data);
886
887 ev = sctp_ulpevent_make_remote_error(asoc, chunk, 0,
888 GFP_ATOMIC);
889 if (!ev)
890 return;
891
892 sctp_ulpq_tail_event(&asoc->ulpq, ev);
893
894 switch (err_hdr->cause) {
895 case SCTP_ERROR_UNKNOWN_CHUNK:
896 {
897 sctp_chunkhdr_t *unk_chunk_hdr;
898
899 unk_chunk_hdr = (sctp_chunkhdr_t *)err_hdr->variable;
900 switch (unk_chunk_hdr->type) {
901 /* ADDIP 4.1 A9) If the peer responds to an ASCONF with
902 * an ERROR chunk reporting that it did not recognized
903 * the ASCONF chunk type, the sender of the ASCONF MUST
904 * NOT send any further ASCONF chunks and MUST stop its
905 * T-4 timer.
906 */
907 case SCTP_CID_ASCONF:
908 if (asoc->peer.asconf_capable == 0)
909 break;
910
911 asoc->peer.asconf_capable = 0;
912 sctp_add_cmd_sf(cmds, SCTP_CMD_TIMER_STOP,
913 SCTP_TO(SCTP_EVENT_TIMEOUT_T4_RTO));
914 break;
915 default:
916 break;
917 }
918 break;
919 }
920 default:
921 break;
922 }
923 }
924 }
925
926 /* Process variable FWDTSN chunk information. */
927 static void sctp_cmd_process_fwdtsn(struct sctp_ulpq *ulpq,
928 struct sctp_chunk *chunk)
929 {
930 struct sctp_fwdtsn_skip *skip;
931 /* Walk through all the skipped SSNs */
932 sctp_walk_fwdtsn(skip, chunk) {
933 sctp_ulpq_skip(ulpq, ntohs(skip->stream), ntohs(skip->ssn));
934 }
935 }
936
937 /* Helper function to remove the association non-primary peer
938 * transports.
939 */
940 static void sctp_cmd_del_non_primary(struct sctp_association *asoc)
941 {
942 struct sctp_transport *t;
943 struct list_head *pos;
944 struct list_head *temp;
945
946 list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
947 t = list_entry(pos, struct sctp_transport, transports);
948 if (!sctp_cmp_addr_exact(&t->ipaddr,
949 &asoc->peer.primary_addr)) {
950 sctp_assoc_del_peer(asoc, &t->ipaddr);
951 }
952 }
953 }
954
955 /* Helper function to set sk_err on a 1-1 style socket. */
956 static void sctp_cmd_set_sk_err(struct sctp_association *asoc, int error)
957 {
958 struct sock *sk = asoc->base.sk;
959
960 if (!sctp_style(sk, UDP))
961 sk->sk_err = error;
962 }
963
964 /* Helper function to generate an association change event */
965 static void sctp_cmd_assoc_change(sctp_cmd_seq_t *commands,
966 struct sctp_association *asoc,
967 u8 state)
968 {
969 struct sctp_ulpevent *ev;
970
971 ev = sctp_ulpevent_make_assoc_change(asoc, 0, state, 0,
972 asoc->c.sinit_num_ostreams,
973 asoc->c.sinit_max_instreams,
974 NULL, GFP_ATOMIC);
975 if (ev)
976 sctp_ulpq_tail_event(&asoc->ulpq, ev);
977 }
978
979 /* Helper function to generate an adaptation indication event */
980 static void sctp_cmd_adaptation_ind(sctp_cmd_seq_t *commands,
981 struct sctp_association *asoc)
982 {
983 struct sctp_ulpevent *ev;
984
985 ev = sctp_ulpevent_make_adaptation_indication(asoc, GFP_ATOMIC);
986
987 if (ev)
988 sctp_ulpq_tail_event(&asoc->ulpq, ev);
989 }
990
991
992 static void sctp_cmd_t1_timer_update(struct sctp_association *asoc,
993 sctp_event_timeout_t timer,
994 char *name)
995 {
996 struct sctp_transport *t;
997
998 t = asoc->init_last_sent_to;
999 asoc->init_err_counter++;
1000
1001 if (t->init_sent_count > (asoc->init_cycle + 1)) {
1002 asoc->timeouts[timer] *= 2;
1003 if (asoc->timeouts[timer] > asoc->max_init_timeo) {
1004 asoc->timeouts[timer] = asoc->max_init_timeo;
1005 }
1006 asoc->init_cycle++;
1007 SCTP_DEBUG_PRINTK(
1008 "T1 %s Timeout adjustment"
1009 " init_err_counter: %d"
1010 " cycle: %d"
1011 " timeout: %ld\n",
1012 name,
1013 asoc->init_err_counter,
1014 asoc->init_cycle,
1015 asoc->timeouts[timer]);
1016 }
1017
1018 }
1019
1020 /* Send the whole message, chunk by chunk, to the outqueue.
1021 * This way the whole message is queued up and bundling if
1022 * encouraged for small fragments.
1023 */
1024 static int sctp_cmd_send_msg(struct sctp_association *asoc,
1025 struct sctp_datamsg *msg)
1026 {
1027 struct sctp_chunk *chunk;
1028 int error = 0;
1029
1030 list_for_each_entry(chunk, &msg->chunks, frag_list) {
1031 error = sctp_outq_tail(&asoc->outqueue, chunk);
1032 if (error)
1033 break;
1034 }
1035
1036 return error;
1037 }
1038
1039
1040 /* Sent the next ASCONF packet currently stored in the association.
1041 * This happens after the ASCONF_ACK was succeffully processed.
1042 */
1043 static void sctp_cmd_send_asconf(struct sctp_association *asoc)
1044 {
1045 /* Send the next asconf chunk from the addip chunk
1046 * queue.
1047 */
1048 if (!list_empty(&asoc->addip_chunk_list)) {
1049 struct list_head *entry = asoc->addip_chunk_list.next;
1050 struct sctp_chunk *asconf = list_entry(entry,
1051 struct sctp_chunk, list);
1052 list_del_init(entry);
1053
1054 /* Hold the chunk until an ASCONF_ACK is received. */
1055 sctp_chunk_hold(asconf);
1056 if (sctp_primitive_ASCONF(asoc, asconf))
1057 sctp_chunk_free(asconf);
1058 else
1059 asoc->addip_last_asconf = asconf;
1060 }
1061 }
1062
1063
1064 /* These three macros allow us to pull the debugging code out of the
1065 * main flow of sctp_do_sm() to keep attention focused on the real
1066 * functionality there.
1067 */
1068 #define DEBUG_PRE \
1069 SCTP_DEBUG_PRINTK("sctp_do_sm prefn: " \
1070 "ep %p, %s, %s, asoc %p[%s], %s\n", \
1071 ep, sctp_evttype_tbl[event_type], \
1072 (*debug_fn)(subtype), asoc, \
1073 sctp_state_tbl[state], state_fn->name)
1074
1075 #define DEBUG_POST \
1076 SCTP_DEBUG_PRINTK("sctp_do_sm postfn: " \
1077 "asoc %p, status: %s\n", \
1078 asoc, sctp_status_tbl[status])
1079
1080 #define DEBUG_POST_SFX \
1081 SCTP_DEBUG_PRINTK("sctp_do_sm post sfx: error %d, asoc %p[%s]\n", \
1082 error, asoc, \
1083 sctp_state_tbl[(asoc && sctp_id2assoc(ep->base.sk, \
1084 sctp_assoc2id(asoc)))?asoc->state:SCTP_STATE_CLOSED])
1085
1086 /*
1087 * This is the master state machine processing function.
1088 *
1089 * If you want to understand all of lksctp, this is a
1090 * good place to start.
1091 */
1092 int sctp_do_sm(sctp_event_t event_type, sctp_subtype_t subtype,
1093 sctp_state_t state,
1094 struct sctp_endpoint *ep,
1095 struct sctp_association *asoc,
1096 void *event_arg,
1097 gfp_t gfp)
1098 {
1099 sctp_cmd_seq_t commands;
1100 const sctp_sm_table_entry_t *state_fn;
1101 sctp_disposition_t status;
1102 int error = 0;
1103 typedef const char *(printfn_t)(sctp_subtype_t);
1104
1105 static printfn_t *table[] = {
1106 NULL, sctp_cname, sctp_tname, sctp_oname, sctp_pname,
1107 };
1108 printfn_t *debug_fn __attribute__ ((unused)) = table[event_type];
1109
1110 /* Look up the state function, run it, and then process the
1111 * side effects. These three steps are the heart of lksctp.
1112 */
1113 state_fn = sctp_sm_lookup_event(event_type, state, subtype);
1114
1115 sctp_init_cmd_seq(&commands);
1116
1117 DEBUG_PRE;
1118 status = (*state_fn->fn)(ep, asoc, subtype, event_arg, &commands);
1119 DEBUG_POST;
1120
1121 error = sctp_side_effects(event_type, subtype, state,
1122 ep, asoc, event_arg, status,
1123 &commands, gfp);
1124 DEBUG_POST_SFX;
1125
1126 return error;
1127 }
1128
1129 #undef DEBUG_PRE
1130 #undef DEBUG_POST
1131
1132 /*****************************************************************
1133 * This the master state function side effect processing function.
1134 *****************************************************************/
1135 static int sctp_side_effects(sctp_event_t event_type, sctp_subtype_t subtype,
1136 sctp_state_t state,
1137 struct sctp_endpoint *ep,
1138 struct sctp_association *asoc,
1139 void *event_arg,
1140 sctp_disposition_t status,
1141 sctp_cmd_seq_t *commands,
1142 gfp_t gfp)
1143 {
1144 int error;
1145
1146 /* FIXME - Most of the dispositions left today would be categorized
1147 * as "exceptional" dispositions. For those dispositions, it
1148 * may not be proper to run through any of the commands at all.
1149 * For example, the command interpreter might be run only with
1150 * disposition SCTP_DISPOSITION_CONSUME.
1151 */
1152 if (0 != (error = sctp_cmd_interpreter(event_type, subtype, state,
1153 ep, asoc,
1154 event_arg, status,
1155 commands, gfp)))
1156 goto bail;
1157
1158 switch (status) {
1159 case SCTP_DISPOSITION_DISCARD:
1160 SCTP_DEBUG_PRINTK("Ignored sctp protocol event - state %d, "
1161 "event_type %d, event_id %d\n",
1162 state, event_type, subtype.chunk);
1163 break;
1164
1165 case SCTP_DISPOSITION_NOMEM:
1166 /* We ran out of memory, so we need to discard this
1167 * packet.
1168 */
1169 /* BUG--we should now recover some memory, probably by
1170 * reneging...
1171 */
1172 error = -ENOMEM;
1173 break;
1174
1175 case SCTP_DISPOSITION_DELETE_TCB:
1176 /* This should now be a command. */
1177 break;
1178
1179 case SCTP_DISPOSITION_CONSUME:
1180 case SCTP_DISPOSITION_ABORT:
1181 /*
1182 * We should no longer have much work to do here as the
1183 * real work has been done as explicit commands above.
1184 */
1185 break;
1186
1187 case SCTP_DISPOSITION_VIOLATION:
1188 net_err_ratelimited("protocol violation state %d chunkid %d\n",
1189 state, subtype.chunk);
1190 break;
1191
1192 case SCTP_DISPOSITION_NOT_IMPL:
1193 pr_warn("unimplemented feature in state %d, event_type %d, event_id %d\n",
1194 state, event_type, subtype.chunk);
1195 break;
1196
1197 case SCTP_DISPOSITION_BUG:
1198 pr_err("bug in state %d, event_type %d, event_id %d\n",
1199 state, event_type, subtype.chunk);
1200 BUG();
1201 break;
1202
1203 default:
1204 pr_err("impossible disposition %d in state %d, event_type %d, event_id %d\n",
1205 status, state, event_type, subtype.chunk);
1206 BUG();
1207 break;
1208 }
1209
1210 bail:
1211 return error;
1212 }
1213
1214 /********************************************************************
1215 * 2nd Level Abstractions
1216 ********************************************************************/
1217
1218 /* This is the side-effect interpreter. */
1219 static int sctp_cmd_interpreter(sctp_event_t event_type,
1220 sctp_subtype_t subtype,
1221 sctp_state_t state,
1222 struct sctp_endpoint *ep,
1223 struct sctp_association *asoc,
1224 void *event_arg,
1225 sctp_disposition_t status,
1226 sctp_cmd_seq_t *commands,
1227 gfp_t gfp)
1228 {
1229 int error = 0;
1230 int force;
1231 sctp_cmd_t *cmd;
1232 struct sctp_chunk *new_obj;
1233 struct sctp_chunk *chunk = NULL;
1234 struct sctp_packet *packet;
1235 struct timer_list *timer;
1236 unsigned long timeout;
1237 struct sctp_transport *t;
1238 struct sctp_sackhdr sackh;
1239 int local_cork = 0;
1240
1241 if (SCTP_EVENT_T_TIMEOUT != event_type)
1242 chunk = event_arg;
1243
1244 /* Note: This whole file is a huge candidate for rework.
1245 * For example, each command could either have its own handler, so
1246 * the loop would look like:
1247 * while (cmds)
1248 * cmd->handle(x, y, z)
1249 * --jgrimm
1250 */
1251 while (NULL != (cmd = sctp_next_cmd(commands))) {
1252 switch (cmd->verb) {
1253 case SCTP_CMD_NOP:
1254 /* Do nothing. */
1255 break;
1256
1257 case SCTP_CMD_NEW_ASOC:
1258 /* Register a new association. */
1259 if (local_cork) {
1260 sctp_outq_uncork(&asoc->outqueue);
1261 local_cork = 0;
1262 }
1263 asoc = cmd->obj.ptr;
1264 /* Register with the endpoint. */
1265 sctp_endpoint_add_asoc(ep, asoc);
1266 sctp_hash_established(asoc);
1267 break;
1268
1269 case SCTP_CMD_UPDATE_ASSOC:
1270 sctp_assoc_update(asoc, cmd->obj.ptr);
1271 break;
1272
1273 case SCTP_CMD_PURGE_OUTQUEUE:
1274 sctp_outq_teardown(&asoc->outqueue);
1275 break;
1276
1277 case SCTP_CMD_DELETE_TCB:
1278 if (local_cork) {
1279 sctp_outq_uncork(&asoc->outqueue);
1280 local_cork = 0;
1281 }
1282 /* Delete the current association. */
1283 sctp_cmd_delete_tcb(commands, asoc);
1284 asoc = NULL;
1285 break;
1286
1287 case SCTP_CMD_NEW_STATE:
1288 /* Enter a new state. */
1289 sctp_cmd_new_state(commands, asoc, cmd->obj.state);
1290 break;
1291
1292 case SCTP_CMD_REPORT_TSN:
1293 /* Record the arrival of a TSN. */
1294 error = sctp_tsnmap_mark(&asoc->peer.tsn_map,
1295 cmd->obj.u32, NULL);
1296 break;
1297
1298 case SCTP_CMD_REPORT_FWDTSN:
1299 /* Move the Cumulattive TSN Ack ahead. */
1300 sctp_tsnmap_skip(&asoc->peer.tsn_map, cmd->obj.u32);
1301
1302 /* purge the fragmentation queue */
1303 sctp_ulpq_reasm_flushtsn(&asoc->ulpq, cmd->obj.u32);
1304
1305 /* Abort any in progress partial delivery. */
1306 sctp_ulpq_abort_pd(&asoc->ulpq, GFP_ATOMIC);
1307 break;
1308
1309 case SCTP_CMD_PROCESS_FWDTSN:
1310 sctp_cmd_process_fwdtsn(&asoc->ulpq, cmd->obj.ptr);
1311 break;
1312
1313 case SCTP_CMD_GEN_SACK:
1314 /* Generate a Selective ACK.
1315 * The argument tells us whether to just count
1316 * the packet and MAYBE generate a SACK, or
1317 * force a SACK out.
1318 */
1319 force = cmd->obj.i32;
1320 error = sctp_gen_sack(asoc, force, commands);
1321 break;
1322
1323 case SCTP_CMD_PROCESS_SACK:
1324 /* Process an inbound SACK. */
1325 error = sctp_cmd_process_sack(commands, asoc,
1326 cmd->obj.ptr);
1327 break;
1328
1329 case SCTP_CMD_GEN_INIT_ACK:
1330 /* Generate an INIT ACK chunk. */
1331 new_obj = sctp_make_init_ack(asoc, chunk, GFP_ATOMIC,
1332 0);
1333 if (!new_obj)
1334 goto nomem;
1335
1336 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
1337 SCTP_CHUNK(new_obj));
1338 break;
1339
1340 case SCTP_CMD_PEER_INIT:
1341 /* Process a unified INIT from the peer.
1342 * Note: Only used during INIT-ACK processing. If
1343 * there is an error just return to the outter
1344 * layer which will bail.
1345 */
1346 error = sctp_cmd_process_init(commands, asoc, chunk,
1347 cmd->obj.ptr, gfp);
1348 break;
1349
1350 case SCTP_CMD_GEN_COOKIE_ECHO:
1351 /* Generate a COOKIE ECHO chunk. */
1352 new_obj = sctp_make_cookie_echo(asoc, chunk);
1353 if (!new_obj) {
1354 if (cmd->obj.ptr)
1355 sctp_chunk_free(cmd->obj.ptr);
1356 goto nomem;
1357 }
1358 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
1359 SCTP_CHUNK(new_obj));
1360
1361 /* If there is an ERROR chunk to be sent along with
1362 * the COOKIE_ECHO, send it, too.
1363 */
1364 if (cmd->obj.ptr)
1365 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
1366 SCTP_CHUNK(cmd->obj.ptr));
1367
1368 if (new_obj->transport) {
1369 new_obj->transport->init_sent_count++;
1370 asoc->init_last_sent_to = new_obj->transport;
1371 }
1372
1373 /* FIXME - Eventually come up with a cleaner way to
1374 * enabling COOKIE-ECHO + DATA bundling during
1375 * multihoming stale cookie scenarios, the following
1376 * command plays with asoc->peer.retran_path to
1377 * avoid the problem of sending the COOKIE-ECHO and
1378 * DATA in different paths, which could result
1379 * in the association being ABORTed if the DATA chunk
1380 * is processed first by the server. Checking the
1381 * init error counter simply causes this command
1382 * to be executed only during failed attempts of
1383 * association establishment.
1384 */
1385 if ((asoc->peer.retran_path !=
1386 asoc->peer.primary_path) &&
1387 (asoc->init_err_counter > 0)) {
1388 sctp_add_cmd_sf(commands,
1389 SCTP_CMD_FORCE_PRIM_RETRAN,
1390 SCTP_NULL());
1391 }
1392
1393 break;
1394
1395 case SCTP_CMD_GEN_SHUTDOWN:
1396 /* Generate SHUTDOWN when in SHUTDOWN_SENT state.
1397 * Reset error counts.
1398 */
1399 asoc->overall_error_count = 0;
1400
1401 /* Generate a SHUTDOWN chunk. */
1402 new_obj = sctp_make_shutdown(asoc, chunk);
1403 if (!new_obj)
1404 goto nomem;
1405 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
1406 SCTP_CHUNK(new_obj));
1407 break;
1408
1409 case SCTP_CMD_CHUNK_ULP:
1410 /* Send a chunk to the sockets layer. */
1411 SCTP_DEBUG_PRINTK("sm_sideff: %s %p, %s %p.\n",
1412 "chunk_up:", cmd->obj.ptr,
1413 "ulpq:", &asoc->ulpq);
1414 sctp_ulpq_tail_data(&asoc->ulpq, cmd->obj.ptr,
1415 GFP_ATOMIC);
1416 break;
1417
1418 case SCTP_CMD_EVENT_ULP:
1419 /* Send a notification to the sockets layer. */
1420 SCTP_DEBUG_PRINTK("sm_sideff: %s %p, %s %p.\n",
1421 "event_up:",cmd->obj.ptr,
1422 "ulpq:",&asoc->ulpq);
1423 sctp_ulpq_tail_event(&asoc->ulpq, cmd->obj.ptr);
1424 break;
1425
1426 case SCTP_CMD_REPLY:
1427 /* If an caller has not already corked, do cork. */
1428 if (!asoc->outqueue.cork) {
1429 sctp_outq_cork(&asoc->outqueue);
1430 local_cork = 1;
1431 }
1432 /* Send a chunk to our peer. */
1433 error = sctp_outq_tail(&asoc->outqueue, cmd->obj.ptr);
1434 break;
1435
1436 case SCTP_CMD_SEND_PKT:
1437 /* Send a full packet to our peer. */
1438 packet = cmd->obj.ptr;
1439 sctp_packet_transmit(packet);
1440 sctp_ootb_pkt_free(packet);
1441 break;
1442
1443 case SCTP_CMD_T1_RETRAN:
1444 /* Mark a transport for retransmission. */
1445 sctp_retransmit(&asoc->outqueue, cmd->obj.transport,
1446 SCTP_RTXR_T1_RTX);
1447 break;
1448
1449 case SCTP_CMD_RETRAN:
1450 /* Mark a transport for retransmission. */
1451 sctp_retransmit(&asoc->outqueue, cmd->obj.transport,
1452 SCTP_RTXR_T3_RTX);
1453 break;
1454
1455 case SCTP_CMD_ECN_CE:
1456 /* Do delayed CE processing. */
1457 sctp_do_ecn_ce_work(asoc, cmd->obj.u32);
1458 break;
1459
1460 case SCTP_CMD_ECN_ECNE:
1461 /* Do delayed ECNE processing. */
1462 new_obj = sctp_do_ecn_ecne_work(asoc, cmd->obj.u32,
1463 chunk);
1464 if (new_obj)
1465 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
1466 SCTP_CHUNK(new_obj));
1467 break;
1468
1469 case SCTP_CMD_ECN_CWR:
1470 /* Do delayed CWR processing. */
1471 sctp_do_ecn_cwr_work(asoc, cmd->obj.u32);
1472 break;
1473
1474 case SCTP_CMD_SETUP_T2:
1475 sctp_cmd_setup_t2(commands, asoc, cmd->obj.ptr);
1476 break;
1477
1478 case SCTP_CMD_TIMER_START_ONCE:
1479 timer = &asoc->timers[cmd->obj.to];
1480
1481 if (timer_pending(timer))
1482 break;
1483 /* fall through */
1484
1485 case SCTP_CMD_TIMER_START:
1486 timer = &asoc->timers[cmd->obj.to];
1487 timeout = asoc->timeouts[cmd->obj.to];
1488 BUG_ON(!timeout);
1489
1490 timer->expires = jiffies + timeout;
1491 sctp_association_hold(asoc);
1492 add_timer(timer);
1493 break;
1494
1495 case SCTP_CMD_TIMER_RESTART:
1496 timer = &asoc->timers[cmd->obj.to];
1497 timeout = asoc->timeouts[cmd->obj.to];
1498 if (!mod_timer(timer, jiffies + timeout))
1499 sctp_association_hold(asoc);
1500 break;
1501
1502 case SCTP_CMD_TIMER_STOP:
1503 timer = &asoc->timers[cmd->obj.to];
1504 if (timer_pending(timer) && del_timer(timer))
1505 sctp_association_put(asoc);
1506 break;
1507
1508 case SCTP_CMD_INIT_CHOOSE_TRANSPORT:
1509 chunk = cmd->obj.ptr;
1510 t = sctp_assoc_choose_alter_transport(asoc,
1511 asoc->init_last_sent_to);
1512 asoc->init_last_sent_to = t;
1513 chunk->transport = t;
1514 t->init_sent_count++;
1515 /* Set the new transport as primary */
1516 sctp_assoc_set_primary(asoc, t);
1517 break;
1518
1519 case SCTP_CMD_INIT_RESTART:
1520 /* Do the needed accounting and updates
1521 * associated with restarting an initialization
1522 * timer. Only multiply the timeout by two if
1523 * all transports have been tried at the current
1524 * timeout.
1525 */
1526 sctp_cmd_t1_timer_update(asoc,
1527 SCTP_EVENT_TIMEOUT_T1_INIT,
1528 "INIT");
1529
1530 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART,
1531 SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT));
1532 break;
1533
1534 case SCTP_CMD_COOKIEECHO_RESTART:
1535 /* Do the needed accounting and updates
1536 * associated with restarting an initialization
1537 * timer. Only multiply the timeout by two if
1538 * all transports have been tried at the current
1539 * timeout.
1540 */
1541 sctp_cmd_t1_timer_update(asoc,
1542 SCTP_EVENT_TIMEOUT_T1_COOKIE,
1543 "COOKIE");
1544
1545 /* If we've sent any data bundled with
1546 * COOKIE-ECHO we need to resend.
1547 */
1548 list_for_each_entry(t, &asoc->peer.transport_addr_list,
1549 transports) {
1550 sctp_retransmit_mark(&asoc->outqueue, t,
1551 SCTP_RTXR_T1_RTX);
1552 }
1553
1554 sctp_add_cmd_sf(commands,
1555 SCTP_CMD_TIMER_RESTART,
1556 SCTP_TO(SCTP_EVENT_TIMEOUT_T1_COOKIE));
1557 break;
1558
1559 case SCTP_CMD_INIT_FAILED:
1560 sctp_cmd_init_failed(commands, asoc, cmd->obj.err);
1561 break;
1562
1563 case SCTP_CMD_ASSOC_FAILED:
1564 sctp_cmd_assoc_failed(commands, asoc, event_type,
1565 subtype, chunk, cmd->obj.err);
1566 break;
1567
1568 case SCTP_CMD_INIT_COUNTER_INC:
1569 asoc->init_err_counter++;
1570 break;
1571
1572 case SCTP_CMD_INIT_COUNTER_RESET:
1573 asoc->init_err_counter = 0;
1574 asoc->init_cycle = 0;
1575 list_for_each_entry(t, &asoc->peer.transport_addr_list,
1576 transports) {
1577 t->init_sent_count = 0;
1578 }
1579 break;
1580
1581 case SCTP_CMD_REPORT_DUP:
1582 sctp_tsnmap_mark_dup(&asoc->peer.tsn_map,
1583 cmd->obj.u32);
1584 break;
1585
1586 case SCTP_CMD_REPORT_BAD_TAG:
1587 SCTP_DEBUG_PRINTK("vtag mismatch!\n");
1588 break;
1589
1590 case SCTP_CMD_STRIKE:
1591 /* Mark one strike against a transport. */
1592 sctp_do_8_2_transport_strike(commands, asoc,
1593 cmd->obj.transport, 0);
1594 break;
1595
1596 case SCTP_CMD_TRANSPORT_IDLE:
1597 t = cmd->obj.transport;
1598 sctp_transport_lower_cwnd(t, SCTP_LOWER_CWND_INACTIVE);
1599 break;
1600
1601 case SCTP_CMD_TRANSPORT_HB_SENT:
1602 t = cmd->obj.transport;
1603 sctp_do_8_2_transport_strike(commands, asoc,
1604 t, 1);
1605 t->hb_sent = 1;
1606 break;
1607
1608 case SCTP_CMD_TRANSPORT_ON:
1609 t = cmd->obj.transport;
1610 sctp_cmd_transport_on(commands, asoc, t, chunk);
1611 break;
1612
1613 case SCTP_CMD_HB_TIMERS_START:
1614 sctp_cmd_hb_timers_start(commands, asoc);
1615 break;
1616
1617 case SCTP_CMD_HB_TIMER_UPDATE:
1618 t = cmd->obj.transport;
1619 sctp_cmd_hb_timer_update(commands, t);
1620 break;
1621
1622 case SCTP_CMD_HB_TIMERS_STOP:
1623 sctp_cmd_hb_timers_stop(commands, asoc);
1624 break;
1625
1626 case SCTP_CMD_REPORT_ERROR:
1627 error = cmd->obj.error;
1628 break;
1629
1630 case SCTP_CMD_PROCESS_CTSN:
1631 /* Dummy up a SACK for processing. */
1632 sackh.cum_tsn_ack = cmd->obj.be32;
1633 sackh.a_rwnd = asoc->peer.rwnd +
1634 asoc->outqueue.outstanding_bytes;
1635 sackh.num_gap_ack_blocks = 0;
1636 sackh.num_dup_tsns = 0;
1637 sctp_add_cmd_sf(commands, SCTP_CMD_PROCESS_SACK,
1638 SCTP_SACKH(&sackh));
1639 break;
1640
1641 case SCTP_CMD_DISCARD_PACKET:
1642 /* We need to discard the whole packet.
1643 * Uncork the queue since there might be
1644 * responses pending
1645 */
1646 chunk->pdiscard = 1;
1647 if (asoc) {
1648 sctp_outq_uncork(&asoc->outqueue);
1649 local_cork = 0;
1650 }
1651 break;
1652
1653 case SCTP_CMD_RTO_PENDING:
1654 t = cmd->obj.transport;
1655 t->rto_pending = 1;
1656 break;
1657
1658 case SCTP_CMD_PART_DELIVER:
1659 sctp_ulpq_partial_delivery(&asoc->ulpq, cmd->obj.ptr,
1660 GFP_ATOMIC);
1661 break;
1662
1663 case SCTP_CMD_RENEGE:
1664 sctp_ulpq_renege(&asoc->ulpq, cmd->obj.ptr,
1665 GFP_ATOMIC);
1666 break;
1667
1668 case SCTP_CMD_SETUP_T4:
1669 sctp_cmd_setup_t4(commands, asoc, cmd->obj.ptr);
1670 break;
1671
1672 case SCTP_CMD_PROCESS_OPERR:
1673 sctp_cmd_process_operr(commands, asoc, chunk);
1674 break;
1675 case SCTP_CMD_CLEAR_INIT_TAG:
1676 asoc->peer.i.init_tag = 0;
1677 break;
1678 case SCTP_CMD_DEL_NON_PRIMARY:
1679 sctp_cmd_del_non_primary(asoc);
1680 break;
1681 case SCTP_CMD_T3_RTX_TIMERS_STOP:
1682 sctp_cmd_t3_rtx_timers_stop(commands, asoc);
1683 break;
1684 case SCTP_CMD_FORCE_PRIM_RETRAN:
1685 t = asoc->peer.retran_path;
1686 asoc->peer.retran_path = asoc->peer.primary_path;
1687 error = sctp_outq_uncork(&asoc->outqueue);
1688 local_cork = 0;
1689 asoc->peer.retran_path = t;
1690 break;
1691 case SCTP_CMD_SET_SK_ERR:
1692 sctp_cmd_set_sk_err(asoc, cmd->obj.error);
1693 break;
1694 case SCTP_CMD_ASSOC_CHANGE:
1695 sctp_cmd_assoc_change(commands, asoc,
1696 cmd->obj.u8);
1697 break;
1698 case SCTP_CMD_ADAPTATION_IND:
1699 sctp_cmd_adaptation_ind(commands, asoc);
1700 break;
1701
1702 case SCTP_CMD_ASSOC_SHKEY:
1703 error = sctp_auth_asoc_init_active_key(asoc,
1704 GFP_ATOMIC);
1705 break;
1706 case SCTP_CMD_UPDATE_INITTAG:
1707 asoc->peer.i.init_tag = cmd->obj.u32;
1708 break;
1709 case SCTP_CMD_SEND_MSG:
1710 if (!asoc->outqueue.cork) {
1711 sctp_outq_cork(&asoc->outqueue);
1712 local_cork = 1;
1713 }
1714 error = sctp_cmd_send_msg(asoc, cmd->obj.msg);
1715 break;
1716 case SCTP_CMD_SEND_NEXT_ASCONF:
1717 sctp_cmd_send_asconf(asoc);
1718 break;
1719 case SCTP_CMD_PURGE_ASCONF_QUEUE:
1720 sctp_asconf_queue_teardown(asoc);
1721 break;
1722
1723 case SCTP_CMD_SET_ASOC:
1724 asoc = cmd->obj.asoc;
1725 break;
1726
1727 default:
1728 pr_warn("Impossible command: %u, %p\n",
1729 cmd->verb, cmd->obj.ptr);
1730 break;
1731 }
1732
1733 if (error)
1734 break;
1735 }
1736
1737 out:
1738 /* If this is in response to a received chunk, wait until
1739 * we are done with the packet to open the queue so that we don't
1740 * send multiple packets in response to a single request.
1741 */
1742 if (asoc && SCTP_EVENT_T_CHUNK == event_type && chunk) {
1743 if (chunk->end_of_packet || chunk->singleton)
1744 error = sctp_outq_uncork(&asoc->outqueue);
1745 } else if (local_cork)
1746 error = sctp_outq_uncork(&asoc->outqueue);
1747 return error;
1748 nomem:
1749 error = -ENOMEM;
1750 goto out;
1751 }
1752
Linux kernel - Deliverables
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