1 /* SCTP kernel implementation
2 * (C) Copyright IBM Corp. 2001, 2004
3 * Copyright (c) 1999-2000 Cisco, Inc.
4 * Copyright (c) 1999-2001 Motorola, Inc.
5 * Copyright (c) 2001 Intel Corp.
6 * Copyright (c) 2001 La Monte H.P. Yarroll
8 * This file is part of the SCTP kernel implementation
10 * This module provides the abstraction for an SCTP association.
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)
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.
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.
29 * Please send any bug reports or fixes you make to the
31 * lksctp developers <lksctp-developers@lists.sourceforge.net>
33 * Or submit a bug report through the following website:
34 * http://www.sf.net/projects/lksctp
36 * Written or modified by:
37 * La Monte H.P. Yarroll <piggy@acm.org>
38 * Karl Knutson <karl@athena.chicago.il.us>
39 * Jon Grimm <jgrimm@us.ibm.com>
40 * Xingang Guo <xingang.guo@intel.com>
41 * Hui Huang <hui.huang@nokia.com>
42 * Sridhar Samudrala <sri@us.ibm.com>
43 * Daisy Chang <daisyc@us.ibm.com>
44 * Ryan Layer <rmlayer@us.ibm.com>
45 * Kevin Gao <kevin.gao@intel.com>
47 * Any bugs reported given to us we will try to fix... any fixes shared will
48 * be incorporated into the next SCTP release.
51 #include <linux/types.h>
52 #include <linux/fcntl.h>
53 #include <linux/poll.h>
54 #include <linux/init.h>
56 #include <linux/slab.h>
59 #include <net/sctp/sctp.h>
60 #include <net/sctp/sm.h>
62 /* Forward declarations for internal functions. */
63 static void sctp_assoc_bh_rcv(struct work_struct *work);
64 static void sctp_assoc_free_asconf_acks(struct sctp_association *asoc);
67 /* 1st Level Abstractions. */
69 /* Initialize a new association from provided memory. */
70 static struct sctp_association *sctp_association_init(struct sctp_association *asoc,
71 const struct sctp_endpoint *ep,
72 const struct sock *sk,
81 /* Retrieve the SCTP per socket area. */
82 sp = sctp_sk((struct sock *)sk);
84 /* Init all variables to a known value. */
85 memset(asoc, 0, sizeof(struct sctp_association));
87 /* Discarding const is appropriate here. */
88 asoc->ep = (struct sctp_endpoint *)ep;
89 sctp_endpoint_hold(asoc->ep);
92 asoc->base.sk = (struct sock *)sk;
93 sock_hold(asoc->base.sk);
95 /* Initialize the common base substructure. */
96 asoc->base.type = SCTP_EP_TYPE_ASSOCIATION;
98 /* Initialize the object handling fields. */
99 atomic_set(&asoc->base.refcnt, 1);
101 asoc->base.malloced = 0;
103 /* Initialize the bind addr area. */
104 sctp_bind_addr_init(&asoc->base.bind_addr, ep->base.bind_addr.port);
106 asoc->state = SCTP_STATE_CLOSED;
108 /* Set these values from the socket values, a conversion between
109 * millsecons to seconds/microseconds must also be done.
111 asoc->cookie_life.tv_sec = sp->assocparams.sasoc_cookie_life / 1000;
112 asoc->cookie_life.tv_usec = (sp->assocparams.sasoc_cookie_life % 1000)
114 asoc->frag_point = 0;
115 asoc->user_frag = sp->user_frag;
117 /* Set the association max_retrans and RTO values from the
120 asoc->max_retrans = sp->assocparams.sasoc_asocmaxrxt;
121 asoc->rto_initial = msecs_to_jiffies(sp->rtoinfo.srto_initial);
122 asoc->rto_max = msecs_to_jiffies(sp->rtoinfo.srto_max);
123 asoc->rto_min = msecs_to_jiffies(sp->rtoinfo.srto_min);
125 asoc->overall_error_count = 0;
127 /* Initialize the association's heartbeat interval based on the
128 * sock configured value.
130 asoc->hbinterval = msecs_to_jiffies(sp->hbinterval);
132 /* Initialize path max retrans value. */
133 asoc->pathmaxrxt = sp->pathmaxrxt;
135 /* Initialize default path MTU. */
136 asoc->pathmtu = sp->pathmtu;
138 /* Set association default SACK delay */
139 asoc->sackdelay = msecs_to_jiffies(sp->sackdelay);
140 asoc->sackfreq = sp->sackfreq;
142 /* Set the association default flags controlling
143 * Heartbeat, SACK delay, and Path MTU Discovery.
145 asoc->param_flags = sp->param_flags;
147 /* Initialize the maximum mumber of new data packets that can be sent
150 asoc->max_burst = sp->max_burst;
152 /* initialize association timers */
153 asoc->timeouts[SCTP_EVENT_TIMEOUT_NONE] = 0;
154 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_COOKIE] = asoc->rto_initial;
155 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_INIT] = asoc->rto_initial;
156 asoc->timeouts[SCTP_EVENT_TIMEOUT_T2_SHUTDOWN] = asoc->rto_initial;
157 asoc->timeouts[SCTP_EVENT_TIMEOUT_T3_RTX] = 0;
158 asoc->timeouts[SCTP_EVENT_TIMEOUT_T4_RTO] = 0;
160 /* sctpimpguide Section 2.12.2
161 * If the 'T5-shutdown-guard' timer is used, it SHOULD be set to the
162 * recommended value of 5 times 'RTO.Max'.
164 asoc->timeouts[SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD]
167 asoc->timeouts[SCTP_EVENT_TIMEOUT_HEARTBEAT] = 0;
168 asoc->timeouts[SCTP_EVENT_TIMEOUT_SACK] = asoc->sackdelay;
169 asoc->timeouts[SCTP_EVENT_TIMEOUT_AUTOCLOSE] =
172 /* Initilizes the timers */
173 for (i = SCTP_EVENT_TIMEOUT_NONE; i < SCTP_NUM_TIMEOUT_TYPES; ++i)
174 setup_timer(&asoc->timers[i], sctp_timer_events[i],
175 (unsigned long)asoc);
177 /* Pull default initialization values from the sock options.
178 * Note: This assumes that the values have already been
179 * validated in the sock.
181 asoc->c.sinit_max_instreams = sp->initmsg.sinit_max_instreams;
182 asoc->c.sinit_num_ostreams = sp->initmsg.sinit_num_ostreams;
183 asoc->max_init_attempts = sp->initmsg.sinit_max_attempts;
185 asoc->max_init_timeo =
186 msecs_to_jiffies(sp->initmsg.sinit_max_init_timeo);
188 /* Allocate storage for the ssnmap after the inbound and outbound
189 * streams have been negotiated during Init.
193 /* Set the local window size for receive.
194 * This is also the rcvbuf space per association.
195 * RFC 6 - A SCTP receiver MUST be able to receive a minimum of
196 * 1500 bytes in one SCTP packet.
198 if ((sk->sk_rcvbuf/2) < SCTP_DEFAULT_MINWINDOW)
199 asoc->rwnd = SCTP_DEFAULT_MINWINDOW;
201 asoc->rwnd = sk->sk_rcvbuf/2;
203 asoc->a_rwnd = asoc->rwnd;
206 asoc->rwnd_press = 0;
208 /* Use my own max window until I learn something better. */
209 asoc->peer.rwnd = SCTP_DEFAULT_MAXWINDOW;
211 /* Set the sndbuf size for transmit. */
212 asoc->sndbuf_used = 0;
214 /* Initialize the receive memory counter */
215 atomic_set(&asoc->rmem_alloc, 0);
217 init_waitqueue_head(&asoc->wait);
219 asoc->c.my_vtag = sctp_generate_tag(ep);
220 asoc->peer.i.init_tag = 0; /* INIT needs a vtag of 0. */
221 asoc->c.peer_vtag = 0;
223 asoc->c.peer_ttag = 0;
224 asoc->c.my_port = ep->base.bind_addr.port;
226 asoc->c.initial_tsn = sctp_generate_tsn(ep);
228 asoc->next_tsn = asoc->c.initial_tsn;
230 asoc->ctsn_ack_point = asoc->next_tsn - 1;
231 asoc->adv_peer_ack_point = asoc->ctsn_ack_point;
232 asoc->highest_sacked = asoc->ctsn_ack_point;
233 asoc->last_cwr_tsn = asoc->ctsn_ack_point;
234 asoc->unack_data = 0;
236 /* ADDIP Section 4.1 Asconf Chunk Procedures
238 * When an endpoint has an ASCONF signaled change to be sent to the
239 * remote endpoint it should do the following:
241 * A2) a serial number should be assigned to the chunk. The serial
242 * number SHOULD be a monotonically increasing number. The serial
243 * numbers SHOULD be initialized at the start of the
244 * association to the same value as the initial TSN.
246 asoc->addip_serial = asoc->c.initial_tsn;
248 INIT_LIST_HEAD(&asoc->addip_chunk_list);
249 INIT_LIST_HEAD(&asoc->asconf_ack_list);
251 /* Make an empty list of remote transport addresses. */
252 INIT_LIST_HEAD(&asoc->peer.transport_addr_list);
253 asoc->peer.transport_count = 0;
255 /* RFC 2960 5.1 Normal Establishment of an Association
257 * After the reception of the first data chunk in an
258 * association the endpoint must immediately respond with a
259 * sack to acknowledge the data chunk. Subsequent
260 * acknowledgements should be done as described in Section
263 * [We implement this by telling a new association that it
264 * already received one packet.]
266 asoc->peer.sack_needed = 1;
267 asoc->peer.sack_cnt = 0;
269 /* Assume that the peer will tell us if he recognizes ASCONF
270 * as part of INIT exchange.
271 * The sctp_addip_noauth option is there for backward compatibilty
272 * and will revert old behavior.
274 asoc->peer.asconf_capable = 0;
275 if (sctp_addip_noauth)
276 asoc->peer.asconf_capable = 1;
278 /* Create an input queue. */
279 sctp_inq_init(&asoc->base.inqueue);
280 sctp_inq_set_th_handler(&asoc->base.inqueue, sctp_assoc_bh_rcv);
282 /* Create an output queue. */
283 sctp_outq_init(asoc, &asoc->outqueue);
285 if (!sctp_ulpq_init(&asoc->ulpq, asoc))
288 memset(&asoc->peer.tsn_map, 0, sizeof(struct sctp_tsnmap));
294 /* Assume that peer would support both address types unless we are
297 asoc->peer.ipv4_address = 1;
298 if (asoc->base.sk->sk_family == PF_INET6)
299 asoc->peer.ipv6_address = 1;
300 INIT_LIST_HEAD(&asoc->asocs);
302 asoc->autoclose = sp->autoclose;
304 asoc->default_stream = sp->default_stream;
305 asoc->default_ppid = sp->default_ppid;
306 asoc->default_flags = sp->default_flags;
307 asoc->default_context = sp->default_context;
308 asoc->default_timetolive = sp->default_timetolive;
309 asoc->default_rcv_context = sp->default_rcv_context;
311 /* AUTH related initializations */
312 INIT_LIST_HEAD(&asoc->endpoint_shared_keys);
313 err = sctp_auth_asoc_copy_shkeys(ep, asoc, gfp);
317 asoc->active_key_id = ep->active_key_id;
318 asoc->asoc_shared_key = NULL;
320 asoc->default_hmac_id = 0;
321 /* Save the hmacs and chunks list into this association */
322 if (ep->auth_hmacs_list)
323 memcpy(asoc->c.auth_hmacs, ep->auth_hmacs_list,
324 ntohs(ep->auth_hmacs_list->param_hdr.length));
325 if (ep->auth_chunk_list)
326 memcpy(asoc->c.auth_chunks, ep->auth_chunk_list,
327 ntohs(ep->auth_chunk_list->param_hdr.length));
329 /* Get the AUTH random number for this association */
330 p = (sctp_paramhdr_t *)asoc->c.auth_random;
331 p->type = SCTP_PARAM_RANDOM;
332 p->length = htons(sizeof(sctp_paramhdr_t) + SCTP_AUTH_RANDOM_LENGTH);
333 get_random_bytes(p+1, SCTP_AUTH_RANDOM_LENGTH);
338 sctp_endpoint_put(asoc->ep);
339 sock_put(asoc->base.sk);
343 /* Allocate and initialize a new association */
344 struct sctp_association *sctp_association_new(const struct sctp_endpoint *ep,
345 const struct sock *sk,
349 struct sctp_association *asoc;
351 asoc = t_new(struct sctp_association, gfp);
355 if (!sctp_association_init(asoc, ep, sk, scope, gfp))
358 asoc->base.malloced = 1;
359 SCTP_DBG_OBJCNT_INC(assoc);
360 SCTP_DEBUG_PRINTK("Created asoc %p\n", asoc);
370 /* Free this association if possible. There may still be users, so
371 * the actual deallocation may be delayed.
373 void sctp_association_free(struct sctp_association *asoc)
375 struct sock *sk = asoc->base.sk;
376 struct sctp_transport *transport;
377 struct list_head *pos, *temp;
380 /* Only real associations count against the endpoint, so
381 * don't bother for if this is a temporary association.
384 list_del(&asoc->asocs);
386 /* Decrement the backlog value for a TCP-style listening
389 if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING))
390 sk->sk_ack_backlog--;
393 /* Mark as dead, so other users can know this structure is
398 /* Dispose of any data lying around in the outqueue. */
399 sctp_outq_free(&asoc->outqueue);
401 /* Dispose of any pending messages for the upper layer. */
402 sctp_ulpq_free(&asoc->ulpq);
404 /* Dispose of any pending chunks on the inqueue. */
405 sctp_inq_free(&asoc->base.inqueue);
407 sctp_tsnmap_free(&asoc->peer.tsn_map);
409 /* Free ssnmap storage. */
410 sctp_ssnmap_free(asoc->ssnmap);
412 /* Clean up the bound address list. */
413 sctp_bind_addr_free(&asoc->base.bind_addr);
415 /* Do we need to go through all of our timers and
416 * delete them? To be safe we will try to delete all, but we
417 * should be able to go through and make a guess based
420 for (i = SCTP_EVENT_TIMEOUT_NONE; i < SCTP_NUM_TIMEOUT_TYPES; ++i) {
421 if (timer_pending(&asoc->timers[i]) &&
422 del_timer(&asoc->timers[i]))
423 sctp_association_put(asoc);
426 /* Free peer's cached cookie. */
427 kfree(asoc->peer.cookie);
428 kfree(asoc->peer.peer_random);
429 kfree(asoc->peer.peer_chunks);
430 kfree(asoc->peer.peer_hmacs);
432 /* Release the transport structures. */
433 list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
434 transport = list_entry(pos, struct sctp_transport, transports);
436 sctp_transport_free(transport);
439 asoc->peer.transport_count = 0;
441 /* Free any cached ASCONF_ACK chunk. */
442 sctp_assoc_free_asconf_acks(asoc);
444 /* Free any cached ASCONF chunk. */
445 if (asoc->addip_last_asconf)
446 sctp_chunk_free(asoc->addip_last_asconf);
448 /* AUTH - Free the endpoint shared keys */
449 sctp_auth_destroy_keys(&asoc->endpoint_shared_keys);
451 /* AUTH - Free the association shared key */
452 sctp_auth_key_put(asoc->asoc_shared_key);
454 sctp_association_put(asoc);
457 /* Cleanup and free up an association. */
458 static void sctp_association_destroy(struct sctp_association *asoc)
460 SCTP_ASSERT(asoc->base.dead, "Assoc is not dead", return);
462 sctp_endpoint_put(asoc->ep);
463 sock_put(asoc->base.sk);
465 if (asoc->assoc_id != 0) {
466 spin_lock_bh(&sctp_assocs_id_lock);
467 idr_remove(&sctp_assocs_id, asoc->assoc_id);
468 spin_unlock_bh(&sctp_assocs_id_lock);
471 WARN_ON(atomic_read(&asoc->rmem_alloc));
473 if (asoc->base.malloced) {
475 SCTP_DBG_OBJCNT_DEC(assoc);
479 /* Change the primary destination address for the peer. */
480 void sctp_assoc_set_primary(struct sctp_association *asoc,
481 struct sctp_transport *transport)
485 /* it's a changeover only if we already have a primary path
486 * that we are changing
488 if (asoc->peer.primary_path != NULL &&
489 asoc->peer.primary_path != transport)
492 asoc->peer.primary_path = transport;
494 /* Set a default msg_name for events. */
495 memcpy(&asoc->peer.primary_addr, &transport->ipaddr,
496 sizeof(union sctp_addr));
498 /* If the primary path is changing, assume that the
499 * user wants to use this new path.
501 if ((transport->state == SCTP_ACTIVE) ||
502 (transport->state == SCTP_UNKNOWN))
503 asoc->peer.active_path = transport;
506 * SFR-CACC algorithm:
507 * Upon the receipt of a request to change the primary
508 * destination address, on the data structure for the new
509 * primary destination, the sender MUST do the following:
511 * 1) If CHANGEOVER_ACTIVE is set, then there was a switch
512 * to this destination address earlier. The sender MUST set
513 * CYCLING_CHANGEOVER to indicate that this switch is a
514 * double switch to the same destination address.
516 if (transport->cacc.changeover_active)
517 transport->cacc.cycling_changeover = changeover;
519 /* 2) The sender MUST set CHANGEOVER_ACTIVE to indicate that
520 * a changeover has occurred.
522 transport->cacc.changeover_active = changeover;
524 /* 3) The sender MUST store the next TSN to be sent in
525 * next_tsn_at_change.
527 transport->cacc.next_tsn_at_change = asoc->next_tsn;
530 /* Remove a transport from an association. */
531 void sctp_assoc_rm_peer(struct sctp_association *asoc,
532 struct sctp_transport *peer)
534 struct list_head *pos;
535 struct sctp_transport *transport;
537 SCTP_DEBUG_PRINTK_IPADDR("sctp_assoc_rm_peer:association %p addr: ",
541 ntohs(peer->ipaddr.v4.sin_port));
543 /* If we are to remove the current retran_path, update it
544 * to the next peer before removing this peer from the list.
546 if (asoc->peer.retran_path == peer)
547 sctp_assoc_update_retran_path(asoc);
549 /* Remove this peer from the list. */
550 list_del(&peer->transports);
552 /* Get the first transport of asoc. */
553 pos = asoc->peer.transport_addr_list.next;
554 transport = list_entry(pos, struct sctp_transport, transports);
556 /* Update any entries that match the peer to be deleted. */
557 if (asoc->peer.primary_path == peer)
558 sctp_assoc_set_primary(asoc, transport);
559 if (asoc->peer.active_path == peer)
560 asoc->peer.active_path = transport;
561 if (asoc->peer.last_data_from == peer)
562 asoc->peer.last_data_from = transport;
564 /* If we remove the transport an INIT was last sent to, set it to
565 * NULL. Combined with the update of the retran path above, this
566 * will cause the next INIT to be sent to the next available
567 * transport, maintaining the cycle.
569 if (asoc->init_last_sent_to == peer)
570 asoc->init_last_sent_to = NULL;
572 /* If we remove the transport an SHUTDOWN was last sent to, set it
573 * to NULL. Combined with the update of the retran path above, this
574 * will cause the next SHUTDOWN to be sent to the next available
575 * transport, maintaining the cycle.
577 if (asoc->shutdown_last_sent_to == peer)
578 asoc->shutdown_last_sent_to = NULL;
580 /* If we remove the transport an ASCONF was last sent to, set it to
583 if (asoc->addip_last_asconf &&
584 asoc->addip_last_asconf->transport == peer)
585 asoc->addip_last_asconf->transport = NULL;
587 asoc->peer.transport_count--;
589 sctp_transport_free(peer);
592 /* Add a transport address to an association. */
593 struct sctp_transport *sctp_assoc_add_peer(struct sctp_association *asoc,
594 const union sctp_addr *addr,
596 const int peer_state)
598 struct sctp_transport *peer;
599 struct sctp_sock *sp;
602 sp = sctp_sk(asoc->base.sk);
604 /* AF_INET and AF_INET6 share common port field. */
605 port = ntohs(addr->v4.sin_port);
607 SCTP_DEBUG_PRINTK_IPADDR("sctp_assoc_add_peer:association %p addr: ",
608 " port: %d state:%d\n",
614 /* Set the port if it has not been set yet. */
615 if (0 == asoc->peer.port)
616 asoc->peer.port = port;
618 /* Check to see if this is a duplicate. */
619 peer = sctp_assoc_lookup_paddr(asoc, addr);
621 /* An UNKNOWN state is only set on transports added by
622 * user in sctp_connectx() call. Such transports should be
623 * considered CONFIRMED per RFC 4960, Section 5.4.
625 if (peer->state == SCTP_UNKNOWN) {
626 peer->state = SCTP_ACTIVE;
631 peer = sctp_transport_new(addr, gfp);
635 sctp_transport_set_owner(peer, asoc);
637 /* Initialize the peer's heartbeat interval based on the
638 * association configured value.
640 peer->hbinterval = asoc->hbinterval;
642 /* Set the path max_retrans. */
643 peer->pathmaxrxt = asoc->pathmaxrxt;
645 /* Initialize the peer's SACK delay timeout based on the
646 * association configured value.
648 peer->sackdelay = asoc->sackdelay;
649 peer->sackfreq = asoc->sackfreq;
651 /* Enable/disable heartbeat, SACK delay, and path MTU discovery
652 * based on association setting.
654 peer->param_flags = asoc->param_flags;
656 /* Initialize the pmtu of the transport. */
657 if (peer->param_flags & SPP_PMTUD_ENABLE)
658 sctp_transport_pmtu(peer);
659 else if (asoc->pathmtu)
660 peer->pathmtu = asoc->pathmtu;
662 peer->pathmtu = SCTP_DEFAULT_MAXSEGMENT;
664 /* If this is the first transport addr on this association,
665 * initialize the association PMTU to the peer's PMTU.
666 * If not and the current association PMTU is higher than the new
667 * peer's PMTU, reset the association PMTU to the new peer's PMTU.
670 asoc->pathmtu = min_t(int, peer->pathmtu, asoc->pathmtu);
672 asoc->pathmtu = peer->pathmtu;
674 SCTP_DEBUG_PRINTK("sctp_assoc_add_peer:association %p PMTU set to "
675 "%d\n", asoc, asoc->pathmtu);
676 peer->pmtu_pending = 0;
678 asoc->frag_point = sctp_frag_point(asoc, asoc->pathmtu);
680 /* The asoc->peer.port might not be meaningful yet, but
681 * initialize the packet structure anyway.
683 sctp_packet_init(&peer->packet, peer, asoc->base.bind_addr.port,
688 * o The initial cwnd before DATA transmission or after a sufficiently
689 * long idle period MUST be set to
690 * min(4*MTU, max(2*MTU, 4380 bytes))
692 * o The initial value of ssthresh MAY be arbitrarily high
693 * (for example, implementations MAY use the size of the
694 * receiver advertised window).
696 peer->cwnd = min(4*asoc->pathmtu, max_t(__u32, 2*asoc->pathmtu, 4380));
698 /* At this point, we may not have the receiver's advertised window,
699 * so initialize ssthresh to the default value and it will be set
700 * later when we process the INIT.
702 peer->ssthresh = SCTP_DEFAULT_MAXWINDOW;
704 peer->partial_bytes_acked = 0;
705 peer->flight_size = 0;
707 /* Set the transport's RTO.initial value */
708 peer->rto = asoc->rto_initial;
710 /* Set the peer's active state. */
711 peer->state = peer_state;
713 /* Attach the remote transport to our asoc. */
714 list_add_tail(&peer->transports, &asoc->peer.transport_addr_list);
715 asoc->peer.transport_count++;
717 /* If we do not yet have a primary path, set one. */
718 if (!asoc->peer.primary_path) {
719 sctp_assoc_set_primary(asoc, peer);
720 asoc->peer.retran_path = peer;
723 if (asoc->peer.active_path == asoc->peer.retran_path) {
724 asoc->peer.retran_path = peer;
730 /* Delete a transport address from an association. */
731 void sctp_assoc_del_peer(struct sctp_association *asoc,
732 const union sctp_addr *addr)
734 struct list_head *pos;
735 struct list_head *temp;
736 struct sctp_transport *transport;
738 list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
739 transport = list_entry(pos, struct sctp_transport, transports);
740 if (sctp_cmp_addr_exact(addr, &transport->ipaddr)) {
741 /* Do book keeping for removing the peer and free it. */
742 sctp_assoc_rm_peer(asoc, transport);
748 /* Lookup a transport by address. */
749 struct sctp_transport *sctp_assoc_lookup_paddr(
750 const struct sctp_association *asoc,
751 const union sctp_addr *address)
753 struct sctp_transport *t;
755 /* Cycle through all transports searching for a peer address. */
757 list_for_each_entry(t, &asoc->peer.transport_addr_list,
759 if (sctp_cmp_addr_exact(address, &t->ipaddr))
766 /* Remove all transports except a give one */
767 void sctp_assoc_del_nonprimary_peers(struct sctp_association *asoc,
768 struct sctp_transport *primary)
770 struct sctp_transport *temp;
771 struct sctp_transport *t;
773 list_for_each_entry_safe(t, temp, &asoc->peer.transport_addr_list,
775 /* if the current transport is not the primary one, delete it */
777 sctp_assoc_rm_peer(asoc, t);
783 /* Engage in transport control operations.
784 * Mark the transport up or down and send a notification to the user.
785 * Select and update the new active and retran paths.
787 void sctp_assoc_control_transport(struct sctp_association *asoc,
788 struct sctp_transport *transport,
789 sctp_transport_cmd_t command,
790 sctp_sn_error_t error)
792 struct sctp_transport *t = NULL;
793 struct sctp_transport *first;
794 struct sctp_transport *second;
795 struct sctp_ulpevent *event;
796 struct sockaddr_storage addr;
799 /* Record the transition on the transport. */
801 case SCTP_TRANSPORT_UP:
802 /* If we are moving from UNCONFIRMED state due
803 * to heartbeat success, report the SCTP_ADDR_CONFIRMED
804 * state to the user, otherwise report SCTP_ADDR_AVAILABLE.
806 if (SCTP_UNCONFIRMED == transport->state &&
807 SCTP_HEARTBEAT_SUCCESS == error)
808 spc_state = SCTP_ADDR_CONFIRMED;
810 spc_state = SCTP_ADDR_AVAILABLE;
811 transport->state = SCTP_ACTIVE;
814 case SCTP_TRANSPORT_DOWN:
815 /* If the transport was never confirmed, do not transition it
816 * to inactive state. Also, release the cached route since
817 * there may be a better route next time.
819 if (transport->state != SCTP_UNCONFIRMED)
820 transport->state = SCTP_INACTIVE;
822 dst_release(transport->dst);
823 transport->dst = NULL;
826 spc_state = SCTP_ADDR_UNREACHABLE;
833 /* Generate and send a SCTP_PEER_ADDR_CHANGE notification to the
836 memset(&addr, 0, sizeof(struct sockaddr_storage));
837 memcpy(&addr, &transport->ipaddr, transport->af_specific->sockaddr_len);
838 event = sctp_ulpevent_make_peer_addr_change(asoc, &addr,
839 0, spc_state, error, GFP_ATOMIC);
841 sctp_ulpq_tail_event(&asoc->ulpq, event);
843 /* Select new active and retran paths. */
845 /* Look for the two most recently used active transports.
847 * This code produces the wrong ordering whenever jiffies
848 * rolls over, but we still get usable transports, so we don't
851 first = NULL; second = NULL;
853 list_for_each_entry(t, &asoc->peer.transport_addr_list,
856 if ((t->state == SCTP_INACTIVE) ||
857 (t->state == SCTP_UNCONFIRMED))
859 if (!first || t->last_time_heard > first->last_time_heard) {
863 if (!second || t->last_time_heard > second->last_time_heard)
867 /* RFC 2960 6.4 Multi-Homed SCTP Endpoints
869 * By default, an endpoint should always transmit to the
870 * primary path, unless the SCTP user explicitly specifies the
871 * destination transport address (and possibly source
872 * transport address) to use.
874 * [If the primary is active but not most recent, bump the most
875 * recently used transport.]
877 if (((asoc->peer.primary_path->state == SCTP_ACTIVE) ||
878 (asoc->peer.primary_path->state == SCTP_UNKNOWN)) &&
879 first != asoc->peer.primary_path) {
881 first = asoc->peer.primary_path;
884 /* If we failed to find a usable transport, just camp on the
885 * primary, even if it is inactive.
888 first = asoc->peer.primary_path;
889 second = asoc->peer.primary_path;
892 /* Set the active and retran transports. */
893 asoc->peer.active_path = first;
894 asoc->peer.retran_path = second;
897 /* Hold a reference to an association. */
898 void sctp_association_hold(struct sctp_association *asoc)
900 atomic_inc(&asoc->base.refcnt);
903 /* Release a reference to an association and cleanup
904 * if there are no more references.
906 void sctp_association_put(struct sctp_association *asoc)
908 if (atomic_dec_and_test(&asoc->base.refcnt))
909 sctp_association_destroy(asoc);
912 /* Allocate the next TSN, Transmission Sequence Number, for the given
915 __u32 sctp_association_get_next_tsn(struct sctp_association *asoc)
917 /* From Section 1.6 Serial Number Arithmetic:
918 * Transmission Sequence Numbers wrap around when they reach
919 * 2**32 - 1. That is, the next TSN a DATA chunk MUST use
920 * after transmitting TSN = 2*32 - 1 is TSN = 0.
922 __u32 retval = asoc->next_tsn;
929 /* Compare two addresses to see if they match. Wildcard addresses
930 * only match themselves.
932 int sctp_cmp_addr_exact(const union sctp_addr *ss1,
933 const union sctp_addr *ss2)
937 af = sctp_get_af_specific(ss1->sa.sa_family);
941 return af->cmp_addr(ss1, ss2);
944 /* Return an ecne chunk to get prepended to a packet.
945 * Note: We are sly and return a shared, prealloced chunk. FIXME:
946 * No we don't, but we could/should.
948 struct sctp_chunk *sctp_get_ecne_prepend(struct sctp_association *asoc)
950 struct sctp_chunk *chunk;
952 /* Send ECNE if needed.
953 * Not being able to allocate a chunk here is not deadly.
956 chunk = sctp_make_ecne(asoc, asoc->last_ecne_tsn);
964 * Find which transport this TSN was sent on.
966 struct sctp_transport *sctp_assoc_lookup_tsn(struct sctp_association *asoc,
969 struct sctp_transport *active;
970 struct sctp_transport *match;
971 struct sctp_transport *transport;
972 struct sctp_chunk *chunk;
973 __be32 key = htonl(tsn);
978 * FIXME: In general, find a more efficient data structure for
983 * The general strategy is to search each transport's transmitted
984 * list. Return which transport this TSN lives on.
986 * Let's be hopeful and check the active_path first.
987 * Another optimization would be to know if there is only one
988 * outbound path and not have to look for the TSN at all.
992 active = asoc->peer.active_path;
994 list_for_each_entry(chunk, &active->transmitted,
997 if (key == chunk->subh.data_hdr->tsn) {
1003 /* If not found, go search all the other transports. */
1004 list_for_each_entry(transport, &asoc->peer.transport_addr_list,
1007 if (transport == active)
1009 list_for_each_entry(chunk, &transport->transmitted,
1011 if (key == chunk->subh.data_hdr->tsn) {
1021 /* Is this the association we are looking for? */
1022 struct sctp_transport *sctp_assoc_is_match(struct sctp_association *asoc,
1023 const union sctp_addr *laddr,
1024 const union sctp_addr *paddr)
1026 struct sctp_transport *transport;
1028 if ((htons(asoc->base.bind_addr.port) == laddr->v4.sin_port) &&
1029 (htons(asoc->peer.port) == paddr->v4.sin_port)) {
1030 transport = sctp_assoc_lookup_paddr(asoc, paddr);
1034 if (sctp_bind_addr_match(&asoc->base.bind_addr, laddr,
1035 sctp_sk(asoc->base.sk)))
1044 /* Do delayed input processing. This is scheduled by sctp_rcv(). */
1045 static void sctp_assoc_bh_rcv(struct work_struct *work)
1047 struct sctp_association *asoc =
1048 container_of(work, struct sctp_association,
1049 base.inqueue.immediate);
1050 struct sctp_endpoint *ep;
1051 struct sctp_chunk *chunk;
1053 struct sctp_inq *inqueue;
1055 sctp_subtype_t subtype;
1058 /* The association should be held so we should be safe. */
1062 inqueue = &asoc->base.inqueue;
1063 sctp_association_hold(asoc);
1064 while (NULL != (chunk = sctp_inq_pop(inqueue))) {
1065 state = asoc->state;
1066 subtype = SCTP_ST_CHUNK(chunk->chunk_hdr->type);
1068 /* SCTP-AUTH, Section 6.3:
1069 * The receiver has a list of chunk types which it expects
1070 * to be received only after an AUTH-chunk. This list has
1071 * been sent to the peer during the association setup. It
1072 * MUST silently discard these chunks if they are not placed
1073 * after an AUTH chunk in the packet.
1075 if (sctp_auth_recv_cid(subtype.chunk, asoc) && !chunk->auth)
1078 /* Remember where the last DATA chunk came from so we
1079 * know where to send the SACK.
1081 if (sctp_chunk_is_data(chunk))
1082 asoc->peer.last_data_from = chunk->transport;
1084 SCTP_INC_STATS(SCTP_MIB_INCTRLCHUNKS);
1086 if (chunk->transport)
1087 chunk->transport->last_time_heard = jiffies;
1089 /* Run through the state machine. */
1090 error = sctp_do_sm(SCTP_EVENT_T_CHUNK, subtype,
1091 state, ep, asoc, chunk, GFP_ATOMIC);
1093 /* Check to see if the association is freed in response to
1094 * the incoming chunk. If so, get out of the while loop.
1096 if (asoc->base.dead)
1099 /* If there is an error on chunk, discard this packet. */
1101 chunk->pdiscard = 1;
1103 sctp_association_put(asoc);
1106 /* This routine moves an association from its old sk to a new sk. */
1107 void sctp_assoc_migrate(struct sctp_association *assoc, struct sock *newsk)
1109 struct sctp_sock *newsp = sctp_sk(newsk);
1110 struct sock *oldsk = assoc->base.sk;
1112 /* Delete the association from the old endpoint's list of
1115 list_del_init(&assoc->asocs);
1117 /* Decrement the backlog value for a TCP-style socket. */
1118 if (sctp_style(oldsk, TCP))
1119 oldsk->sk_ack_backlog--;
1121 /* Release references to the old endpoint and the sock. */
1122 sctp_endpoint_put(assoc->ep);
1123 sock_put(assoc->base.sk);
1125 /* Get a reference to the new endpoint. */
1126 assoc->ep = newsp->ep;
1127 sctp_endpoint_hold(assoc->ep);
1129 /* Get a reference to the new sock. */
1130 assoc->base.sk = newsk;
1131 sock_hold(assoc->base.sk);
1133 /* Add the association to the new endpoint's list of associations. */
1134 sctp_endpoint_add_asoc(newsp->ep, assoc);
1137 /* Update an association (possibly from unexpected COOKIE-ECHO processing). */
1138 void sctp_assoc_update(struct sctp_association *asoc,
1139 struct sctp_association *new)
1141 struct sctp_transport *trans;
1142 struct list_head *pos, *temp;
1144 /* Copy in new parameters of peer. */
1146 asoc->peer.rwnd = new->peer.rwnd;
1147 asoc->peer.sack_needed = new->peer.sack_needed;
1148 asoc->peer.i = new->peer.i;
1149 sctp_tsnmap_init(&asoc->peer.tsn_map, SCTP_TSN_MAP_INITIAL,
1150 asoc->peer.i.initial_tsn, GFP_ATOMIC);
1152 /* Remove any peer addresses not present in the new association. */
1153 list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
1154 trans = list_entry(pos, struct sctp_transport, transports);
1155 if (!sctp_assoc_lookup_paddr(new, &trans->ipaddr))
1156 sctp_assoc_del_peer(asoc, &trans->ipaddr);
1158 if (asoc->state >= SCTP_STATE_ESTABLISHED)
1159 sctp_transport_reset(trans);
1162 /* If the case is A (association restart), use
1163 * initial_tsn as next_tsn. If the case is B, use
1164 * current next_tsn in case data sent to peer
1165 * has been discarded and needs retransmission.
1167 if (asoc->state >= SCTP_STATE_ESTABLISHED) {
1168 asoc->next_tsn = new->next_tsn;
1169 asoc->ctsn_ack_point = new->ctsn_ack_point;
1170 asoc->adv_peer_ack_point = new->adv_peer_ack_point;
1172 /* Reinitialize SSN for both local streams
1173 * and peer's streams.
1175 sctp_ssnmap_clear(asoc->ssnmap);
1177 /* Flush the ULP reassembly and ordered queue.
1178 * Any data there will now be stale and will
1181 sctp_ulpq_flush(&asoc->ulpq);
1183 /* reset the overall association error count so
1184 * that the restarted association doesn't get torn
1185 * down on the next retransmission timer.
1187 asoc->overall_error_count = 0;
1190 /* Add any peer addresses from the new association. */
1191 list_for_each_entry(trans, &new->peer.transport_addr_list,
1193 if (!sctp_assoc_lookup_paddr(asoc, &trans->ipaddr))
1194 sctp_assoc_add_peer(asoc, &trans->ipaddr,
1195 GFP_ATOMIC, trans->state);
1198 asoc->ctsn_ack_point = asoc->next_tsn - 1;
1199 asoc->adv_peer_ack_point = asoc->ctsn_ack_point;
1200 if (!asoc->ssnmap) {
1201 /* Move the ssnmap. */
1202 asoc->ssnmap = new->ssnmap;
1206 if (!asoc->assoc_id) {
1207 /* get a new association id since we don't have one
1210 sctp_assoc_set_id(asoc, GFP_ATOMIC);
1214 /* SCTP-AUTH: Save the peer parameters from the new assocaitions
1215 * and also move the association shared keys over
1217 kfree(asoc->peer.peer_random);
1218 asoc->peer.peer_random = new->peer.peer_random;
1219 new->peer.peer_random = NULL;
1221 kfree(asoc->peer.peer_chunks);
1222 asoc->peer.peer_chunks = new->peer.peer_chunks;
1223 new->peer.peer_chunks = NULL;
1225 kfree(asoc->peer.peer_hmacs);
1226 asoc->peer.peer_hmacs = new->peer.peer_hmacs;
1227 new->peer.peer_hmacs = NULL;
1229 sctp_auth_key_put(asoc->asoc_shared_key);
1230 sctp_auth_asoc_init_active_key(asoc, GFP_ATOMIC);
1233 /* Update the retran path for sending a retransmitted packet.
1234 * Round-robin through the active transports, else round-robin
1235 * through the inactive transports as this is the next best thing
1238 void sctp_assoc_update_retran_path(struct sctp_association *asoc)
1240 struct sctp_transport *t, *next;
1241 struct list_head *head = &asoc->peer.transport_addr_list;
1242 struct list_head *pos;
1244 if (asoc->peer.transport_count == 1)
1247 /* Find the next transport in a round-robin fashion. */
1248 t = asoc->peer.retran_path;
1249 pos = &t->transports;
1253 /* Skip the head. */
1254 if (pos->next == head)
1259 t = list_entry(pos, struct sctp_transport, transports);
1261 /* We have exhausted the list, but didn't find any
1262 * other active transports. If so, use the next
1265 if (t == asoc->peer.retran_path) {
1270 /* Try to find an active transport. */
1272 if ((t->state == SCTP_ACTIVE) ||
1273 (t->state == SCTP_UNKNOWN)) {
1276 /* Keep track of the next transport in case
1277 * we don't find any active transport.
1284 asoc->peer.retran_path = t;
1286 SCTP_DEBUG_PRINTK_IPADDR("sctp_assoc_update_retran_path:association"
1291 ntohs(t->ipaddr.v4.sin_port));
1294 /* Choose the transport for sending retransmit packet. */
1295 struct sctp_transport *sctp_assoc_choose_alter_transport(
1296 struct sctp_association *asoc, struct sctp_transport *last_sent_to)
1298 /* If this is the first time packet is sent, use the active path,
1299 * else use the retran path. If the last packet was sent over the
1300 * retran path, update the retran path and use it.
1303 return asoc->peer.active_path;
1305 if (last_sent_to == asoc->peer.retran_path)
1306 sctp_assoc_update_retran_path(asoc);
1307 return asoc->peer.retran_path;
1311 /* Update the association's pmtu and frag_point by going through all the
1312 * transports. This routine is called when a transport's PMTU has changed.
1314 void sctp_assoc_sync_pmtu(struct sctp_association *asoc)
1316 struct sctp_transport *t;
1322 /* Get the lowest pmtu of all the transports. */
1323 list_for_each_entry(t, &asoc->peer.transport_addr_list,
1325 if (t->pmtu_pending && t->dst) {
1326 sctp_transport_update_pmtu(t, dst_mtu(t->dst));
1327 t->pmtu_pending = 0;
1329 if (!pmtu || (t->pathmtu < pmtu))
1334 asoc->pathmtu = pmtu;
1335 asoc->frag_point = sctp_frag_point(asoc, pmtu);
1338 SCTP_DEBUG_PRINTK("%s: asoc:%p, pmtu:%d, frag_point:%d\n",
1339 __func__, asoc, asoc->pathmtu, asoc->frag_point);
1342 /* Should we send a SACK to update our peer? */
1343 static inline int sctp_peer_needs_update(struct sctp_association *asoc)
1345 switch (asoc->state) {
1346 case SCTP_STATE_ESTABLISHED:
1347 case SCTP_STATE_SHUTDOWN_PENDING:
1348 case SCTP_STATE_SHUTDOWN_RECEIVED:
1349 case SCTP_STATE_SHUTDOWN_SENT:
1350 if ((asoc->rwnd > asoc->a_rwnd) &&
1351 ((asoc->rwnd - asoc->a_rwnd) >=
1352 min_t(__u32, (asoc->base.sk->sk_rcvbuf >> 1), asoc->pathmtu)))
1361 /* Increase asoc's rwnd by len and send any window update SACK if needed. */
1362 void sctp_assoc_rwnd_increase(struct sctp_association *asoc, unsigned len)
1364 struct sctp_chunk *sack;
1365 struct timer_list *timer;
1367 if (asoc->rwnd_over) {
1368 if (asoc->rwnd_over >= len) {
1369 asoc->rwnd_over -= len;
1371 asoc->rwnd += (len - asoc->rwnd_over);
1372 asoc->rwnd_over = 0;
1378 /* If we had window pressure, start recovering it
1379 * once our rwnd had reached the accumulated pressure
1380 * threshold. The idea is to recover slowly, but up
1381 * to the initial advertised window.
1383 if (asoc->rwnd_press && asoc->rwnd >= asoc->rwnd_press) {
1384 int change = min(asoc->pathmtu, asoc->rwnd_press);
1385 asoc->rwnd += change;
1386 asoc->rwnd_press -= change;
1389 SCTP_DEBUG_PRINTK("%s: asoc %p rwnd increased by %d to (%u, %u) "
1390 "- %u\n", __func__, asoc, len, asoc->rwnd,
1391 asoc->rwnd_over, asoc->a_rwnd);
1393 /* Send a window update SACK if the rwnd has increased by at least the
1394 * minimum of the association's PMTU and half of the receive buffer.
1395 * The algorithm used is similar to the one described in
1396 * Section 4.2.3.3 of RFC 1122.
1398 if (sctp_peer_needs_update(asoc)) {
1399 asoc->a_rwnd = asoc->rwnd;
1400 SCTP_DEBUG_PRINTK("%s: Sending window update SACK- asoc: %p "
1401 "rwnd: %u a_rwnd: %u\n", __func__,
1402 asoc, asoc->rwnd, asoc->a_rwnd);
1403 sack = sctp_make_sack(asoc);
1407 asoc->peer.sack_needed = 0;
1409 sctp_outq_tail(&asoc->outqueue, sack);
1411 /* Stop the SACK timer. */
1412 timer = &asoc->timers[SCTP_EVENT_TIMEOUT_SACK];
1413 if (timer_pending(timer) && del_timer(timer))
1414 sctp_association_put(asoc);
1418 /* Decrease asoc's rwnd by len. */
1419 void sctp_assoc_rwnd_decrease(struct sctp_association *asoc, unsigned len)
1424 SCTP_ASSERT(asoc->rwnd, "rwnd zero", return);
1425 SCTP_ASSERT(!asoc->rwnd_over, "rwnd_over not zero", return);
1427 if (asoc->ep->rcvbuf_policy)
1428 rx_count = atomic_read(&asoc->rmem_alloc);
1430 rx_count = atomic_read(&asoc->base.sk->sk_rmem_alloc);
1432 /* If we've reached or overflowed our receive buffer, announce
1433 * a 0 rwnd if rwnd would still be positive. Store the
1434 * the pottential pressure overflow so that the window can be restored
1435 * back to original value.
1437 if (rx_count >= asoc->base.sk->sk_rcvbuf)
1440 if (asoc->rwnd >= len) {
1443 asoc->rwnd_press = asoc->rwnd;
1447 asoc->rwnd_over = len - asoc->rwnd;
1450 SCTP_DEBUG_PRINTK("%s: asoc %p rwnd decreased by %d to (%u, %u, %u)\n",
1451 __func__, asoc, len, asoc->rwnd,
1452 asoc->rwnd_over, asoc->rwnd_press);
1455 /* Build the bind address list for the association based on info from the
1456 * local endpoint and the remote peer.
1458 int sctp_assoc_set_bind_addr_from_ep(struct sctp_association *asoc,
1464 /* Use scoping rules to determine the subset of addresses from
1467 scope = sctp_scope(&asoc->peer.active_path->ipaddr);
1468 flags = (PF_INET6 == asoc->base.sk->sk_family) ? SCTP_ADDR6_ALLOWED : 0;
1469 if (asoc->peer.ipv4_address)
1470 flags |= SCTP_ADDR4_PEERSUPP;
1471 if (asoc->peer.ipv6_address)
1472 flags |= SCTP_ADDR6_PEERSUPP;
1474 return sctp_bind_addr_copy(&asoc->base.bind_addr,
1475 &asoc->ep->base.bind_addr,
1479 /* Build the association's bind address list from the cookie. */
1480 int sctp_assoc_set_bind_addr_from_cookie(struct sctp_association *asoc,
1481 struct sctp_cookie *cookie,
1484 int var_size2 = ntohs(cookie->peer_init->chunk_hdr.length);
1485 int var_size3 = cookie->raw_addr_list_len;
1486 __u8 *raw = (__u8 *)cookie->peer_init + var_size2;
1488 return sctp_raw_to_bind_addrs(&asoc->base.bind_addr, raw, var_size3,
1489 asoc->ep->base.bind_addr.port, gfp);
1492 /* Lookup laddr in the bind address list of an association. */
1493 int sctp_assoc_lookup_laddr(struct sctp_association *asoc,
1494 const union sctp_addr *laddr)
1498 if ((asoc->base.bind_addr.port == ntohs(laddr->v4.sin_port)) &&
1499 sctp_bind_addr_match(&asoc->base.bind_addr, laddr,
1500 sctp_sk(asoc->base.sk)))
1506 /* Set an association id for a given association */
1507 int sctp_assoc_set_id(struct sctp_association *asoc, gfp_t gfp)
1512 /* If the id is already assigned, keep it. */
1516 if (unlikely(!idr_pre_get(&sctp_assocs_id, gfp)))
1519 spin_lock_bh(&sctp_assocs_id_lock);
1520 error = idr_get_new_above(&sctp_assocs_id, (void *)asoc,
1522 spin_unlock_bh(&sctp_assocs_id_lock);
1523 if (error == -EAGAIN)
1528 asoc->assoc_id = (sctp_assoc_t) assoc_id;
1532 /* Free asconf_ack cache */
1533 static void sctp_assoc_free_asconf_acks(struct sctp_association *asoc)
1535 struct sctp_chunk *ack;
1536 struct sctp_chunk *tmp;
1538 list_for_each_entry_safe(ack, tmp, &asoc->asconf_ack_list,
1540 list_del_init(&ack->transmitted_list);
1541 sctp_chunk_free(ack);
1545 /* Clean up the ASCONF_ACK queue */
1546 void sctp_assoc_clean_asconf_ack_cache(const struct sctp_association *asoc)
1548 struct sctp_chunk *ack;
1549 struct sctp_chunk *tmp;
1551 /* We can remove all the entries from the queue upto
1552 * the "Peer-Sequence-Number".
1554 list_for_each_entry_safe(ack, tmp, &asoc->asconf_ack_list,
1556 if (ack->subh.addip_hdr->serial ==
1557 htonl(asoc->peer.addip_serial))
1560 list_del_init(&ack->transmitted_list);
1561 sctp_chunk_free(ack);
1565 /* Find the ASCONF_ACK whose serial number matches ASCONF */
1566 struct sctp_chunk *sctp_assoc_lookup_asconf_ack(
1567 const struct sctp_association *asoc,
1570 struct sctp_chunk *ack;
1572 /* Walk through the list of cached ASCONF-ACKs and find the
1573 * ack chunk whose serial number matches that of the request.
1575 list_for_each_entry(ack, &asoc->asconf_ack_list, transmitted_list) {
1576 if (ack->subh.addip_hdr->serial == serial) {
1577 sctp_chunk_hold(ack);