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 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
53 #include <linux/types.h>
54 #include <linux/fcntl.h>
55 #include <linux/poll.h>
56 #include <linux/init.h>
58 #include <linux/slab.h>
61 #include <net/sctp/sctp.h>
62 #include <net/sctp/sm.h>
64 /* Forward declarations for internal functions. */
65 static void sctp_assoc_bh_rcv(struct work_struct *work);
66 static void sctp_assoc_free_asconf_acks(struct sctp_association *asoc);
67 static void sctp_assoc_free_asconf_queue(struct sctp_association *asoc);
69 /* Keep track of the new idr low so that we don't re-use association id
70 * numbers too fast. It is protected by they idr spin lock is in the
71 * range of 1 - INT_MAX.
73 static u32 idr_low = 1;
76 /* 1st Level Abstractions. */
78 /* Initialize a new association from provided memory. */
79 static struct sctp_association *sctp_association_init(struct sctp_association *asoc,
80 const struct sctp_endpoint *ep,
81 const struct sock *sk,
85 struct net *net = sock_net(sk);
91 /* Retrieve the SCTP per socket area. */
92 sp = sctp_sk((struct sock *)sk);
94 /* Discarding const is appropriate here. */
95 asoc->ep = (struct sctp_endpoint *)ep;
96 sctp_endpoint_hold(asoc->ep);
99 asoc->base.sk = (struct sock *)sk;
100 sock_hold(asoc->base.sk);
102 /* Initialize the common base substructure. */
103 asoc->base.type = SCTP_EP_TYPE_ASSOCIATION;
105 /* Initialize the object handling fields. */
106 atomic_set(&asoc->base.refcnt, 1);
109 /* Initialize the bind addr area. */
110 sctp_bind_addr_init(&asoc->base.bind_addr, ep->base.bind_addr.port);
112 asoc->state = SCTP_STATE_CLOSED;
114 /* Set these values from the socket values, a conversion between
115 * millsecons to seconds/microseconds must also be done.
117 asoc->cookie_life.tv_sec = sp->assocparams.sasoc_cookie_life / 1000;
118 asoc->cookie_life.tv_usec = (sp->assocparams.sasoc_cookie_life % 1000)
120 asoc->frag_point = 0;
121 asoc->user_frag = sp->user_frag;
123 /* Set the association max_retrans and RTO values from the
126 asoc->max_retrans = sp->assocparams.sasoc_asocmaxrxt;
127 asoc->pf_retrans = net->sctp.pf_retrans;
129 asoc->rto_initial = msecs_to_jiffies(sp->rtoinfo.srto_initial);
130 asoc->rto_max = msecs_to_jiffies(sp->rtoinfo.srto_max);
131 asoc->rto_min = msecs_to_jiffies(sp->rtoinfo.srto_min);
133 asoc->overall_error_count = 0;
135 /* Initialize the association's heartbeat interval based on the
136 * sock configured value.
138 asoc->hbinterval = msecs_to_jiffies(sp->hbinterval);
140 /* Initialize path max retrans value. */
141 asoc->pathmaxrxt = sp->pathmaxrxt;
143 /* Initialize default path MTU. */
144 asoc->pathmtu = sp->pathmtu;
146 /* Set association default SACK delay */
147 asoc->sackdelay = msecs_to_jiffies(sp->sackdelay);
148 asoc->sackfreq = sp->sackfreq;
150 /* Set the association default flags controlling
151 * Heartbeat, SACK delay, and Path MTU Discovery.
153 asoc->param_flags = sp->param_flags;
155 /* Initialize the maximum mumber of new data packets that can be sent
158 asoc->max_burst = sp->max_burst;
160 /* initialize association timers */
161 asoc->timeouts[SCTP_EVENT_TIMEOUT_NONE] = 0;
162 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_COOKIE] = asoc->rto_initial;
163 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_INIT] = asoc->rto_initial;
164 asoc->timeouts[SCTP_EVENT_TIMEOUT_T2_SHUTDOWN] = asoc->rto_initial;
165 asoc->timeouts[SCTP_EVENT_TIMEOUT_T3_RTX] = 0;
166 asoc->timeouts[SCTP_EVENT_TIMEOUT_T4_RTO] = 0;
168 /* sctpimpguide Section 2.12.2
169 * If the 'T5-shutdown-guard' timer is used, it SHOULD be set to the
170 * recommended value of 5 times 'RTO.Max'.
172 asoc->timeouts[SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD]
175 asoc->timeouts[SCTP_EVENT_TIMEOUT_HEARTBEAT] = 0;
176 asoc->timeouts[SCTP_EVENT_TIMEOUT_SACK] = asoc->sackdelay;
177 asoc->timeouts[SCTP_EVENT_TIMEOUT_AUTOCLOSE] =
178 min_t(unsigned long, sp->autoclose, net->sctp.max_autoclose) * HZ;
180 /* Initializes the timers */
181 for (i = SCTP_EVENT_TIMEOUT_NONE; i < SCTP_NUM_TIMEOUT_TYPES; ++i)
182 setup_timer(&asoc->timers[i], sctp_timer_events[i],
183 (unsigned long)asoc);
185 /* Pull default initialization values from the sock options.
186 * Note: This assumes that the values have already been
187 * validated in the sock.
189 asoc->c.sinit_max_instreams = sp->initmsg.sinit_max_instreams;
190 asoc->c.sinit_num_ostreams = sp->initmsg.sinit_num_ostreams;
191 asoc->max_init_attempts = sp->initmsg.sinit_max_attempts;
193 asoc->max_init_timeo =
194 msecs_to_jiffies(sp->initmsg.sinit_max_init_timeo);
196 /* Allocate storage for the ssnmap after the inbound and outbound
197 * streams have been negotiated during Init.
201 /* Set the local window size for receive.
202 * This is also the rcvbuf space per association.
203 * RFC 6 - A SCTP receiver MUST be able to receive a minimum of
204 * 1500 bytes in one SCTP packet.
206 if ((sk->sk_rcvbuf/2) < SCTP_DEFAULT_MINWINDOW)
207 asoc->rwnd = SCTP_DEFAULT_MINWINDOW;
209 asoc->rwnd = sk->sk_rcvbuf/2;
211 asoc->a_rwnd = asoc->rwnd;
214 asoc->rwnd_press = 0;
216 /* Use my own max window until I learn something better. */
217 asoc->peer.rwnd = SCTP_DEFAULT_MAXWINDOW;
219 /* Set the sndbuf size for transmit. */
220 asoc->sndbuf_used = 0;
222 /* Initialize the receive memory counter */
223 atomic_set(&asoc->rmem_alloc, 0);
225 init_waitqueue_head(&asoc->wait);
227 asoc->c.my_vtag = sctp_generate_tag(ep);
228 asoc->peer.i.init_tag = 0; /* INIT needs a vtag of 0. */
229 asoc->c.peer_vtag = 0;
231 asoc->c.peer_ttag = 0;
232 asoc->c.my_port = ep->base.bind_addr.port;
234 asoc->c.initial_tsn = sctp_generate_tsn(ep);
236 asoc->next_tsn = asoc->c.initial_tsn;
238 asoc->ctsn_ack_point = asoc->next_tsn - 1;
239 asoc->adv_peer_ack_point = asoc->ctsn_ack_point;
240 asoc->highest_sacked = asoc->ctsn_ack_point;
241 asoc->last_cwr_tsn = asoc->ctsn_ack_point;
242 asoc->unack_data = 0;
244 /* ADDIP Section 4.1 Asconf Chunk Procedures
246 * When an endpoint has an ASCONF signaled change to be sent to the
247 * remote endpoint it should do the following:
249 * A2) a serial number should be assigned to the chunk. The serial
250 * number SHOULD be a monotonically increasing number. The serial
251 * numbers SHOULD be initialized at the start of the
252 * association to the same value as the initial TSN.
254 asoc->addip_serial = asoc->c.initial_tsn;
256 INIT_LIST_HEAD(&asoc->addip_chunk_list);
257 INIT_LIST_HEAD(&asoc->asconf_ack_list);
259 /* Make an empty list of remote transport addresses. */
260 INIT_LIST_HEAD(&asoc->peer.transport_addr_list);
261 asoc->peer.transport_count = 0;
263 /* RFC 2960 5.1 Normal Establishment of an Association
265 * After the reception of the first data chunk in an
266 * association the endpoint must immediately respond with a
267 * sack to acknowledge the data chunk. Subsequent
268 * acknowledgements should be done as described in Section
271 * [We implement this by telling a new association that it
272 * already received one packet.]
274 asoc->peer.sack_needed = 1;
275 asoc->peer.sack_cnt = 0;
276 asoc->peer.sack_generation = 1;
278 /* Assume that the peer will tell us if he recognizes ASCONF
279 * as part of INIT exchange.
280 * The sctp_addip_noauth option is there for backward compatibilty
281 * and will revert old behavior.
283 asoc->peer.asconf_capable = 0;
284 if (net->sctp.addip_noauth)
285 asoc->peer.asconf_capable = 1;
286 asoc->asconf_addr_del_pending = NULL;
287 asoc->src_out_of_asoc_ok = 0;
288 asoc->new_transport = NULL;
290 /* Create an input queue. */
291 sctp_inq_init(&asoc->base.inqueue);
292 sctp_inq_set_th_handler(&asoc->base.inqueue, sctp_assoc_bh_rcv);
294 /* Create an output queue. */
295 sctp_outq_init(asoc, &asoc->outqueue);
297 if (!sctp_ulpq_init(&asoc->ulpq, asoc))
300 memset(&asoc->peer.tsn_map, 0, sizeof(struct sctp_tsnmap));
306 /* Assume that peer would support both address types unless we are
309 asoc->peer.ipv4_address = 1;
310 if (asoc->base.sk->sk_family == PF_INET6)
311 asoc->peer.ipv6_address = 1;
312 INIT_LIST_HEAD(&asoc->asocs);
314 asoc->autoclose = sp->autoclose;
316 asoc->default_stream = sp->default_stream;
317 asoc->default_ppid = sp->default_ppid;
318 asoc->default_flags = sp->default_flags;
319 asoc->default_context = sp->default_context;
320 asoc->default_timetolive = sp->default_timetolive;
321 asoc->default_rcv_context = sp->default_rcv_context;
323 /* SCTP_GET_ASSOC_STATS COUNTERS */
324 memset(&asoc->stats, 0, sizeof(struct sctp_priv_assoc_stats));
326 /* AUTH related initializations */
327 INIT_LIST_HEAD(&asoc->endpoint_shared_keys);
328 err = sctp_auth_asoc_copy_shkeys(ep, asoc, gfp);
332 asoc->active_key_id = ep->active_key_id;
333 asoc->asoc_shared_key = NULL;
335 asoc->default_hmac_id = 0;
336 /* Save the hmacs and chunks list into this association */
337 if (ep->auth_hmacs_list)
338 memcpy(asoc->c.auth_hmacs, ep->auth_hmacs_list,
339 ntohs(ep->auth_hmacs_list->param_hdr.length));
340 if (ep->auth_chunk_list)
341 memcpy(asoc->c.auth_chunks, ep->auth_chunk_list,
342 ntohs(ep->auth_chunk_list->param_hdr.length));
344 /* Get the AUTH random number for this association */
345 p = (sctp_paramhdr_t *)asoc->c.auth_random;
346 p->type = SCTP_PARAM_RANDOM;
347 p->length = htons(sizeof(sctp_paramhdr_t) + SCTP_AUTH_RANDOM_LENGTH);
348 get_random_bytes(p+1, SCTP_AUTH_RANDOM_LENGTH);
353 sctp_endpoint_put(asoc->ep);
354 sock_put(asoc->base.sk);
358 /* Allocate and initialize a new association */
359 struct sctp_association *sctp_association_new(const struct sctp_endpoint *ep,
360 const struct sock *sk,
364 struct sctp_association *asoc;
366 asoc = t_new(struct sctp_association, gfp);
370 if (!sctp_association_init(asoc, ep, sk, scope, gfp))
373 SCTP_DBG_OBJCNT_INC(assoc);
374 SCTP_DEBUG_PRINTK("Created asoc %p\n", asoc);
384 /* Free this association if possible. There may still be users, so
385 * the actual deallocation may be delayed.
387 void sctp_association_free(struct sctp_association *asoc)
389 struct sock *sk = asoc->base.sk;
390 struct sctp_transport *transport;
391 struct list_head *pos, *temp;
394 /* Only real associations count against the endpoint, so
395 * don't bother for if this is a temporary association.
398 list_del(&asoc->asocs);
400 /* Decrement the backlog value for a TCP-style listening
403 if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING))
404 sk->sk_ack_backlog--;
407 /* Mark as dead, so other users can know this structure is
412 /* Dispose of any data lying around in the outqueue. */
413 sctp_outq_free(&asoc->outqueue);
415 /* Dispose of any pending messages for the upper layer. */
416 sctp_ulpq_free(&asoc->ulpq);
418 /* Dispose of any pending chunks on the inqueue. */
419 sctp_inq_free(&asoc->base.inqueue);
421 sctp_tsnmap_free(&asoc->peer.tsn_map);
423 /* Free ssnmap storage. */
424 sctp_ssnmap_free(asoc->ssnmap);
426 /* Clean up the bound address list. */
427 sctp_bind_addr_free(&asoc->base.bind_addr);
429 /* Do we need to go through all of our timers and
430 * delete them? To be safe we will try to delete all, but we
431 * should be able to go through and make a guess based
434 for (i = SCTP_EVENT_TIMEOUT_NONE; i < SCTP_NUM_TIMEOUT_TYPES; ++i) {
435 if (del_timer(&asoc->timers[i]))
436 sctp_association_put(asoc);
439 /* Free peer's cached cookie. */
440 kfree(asoc->peer.cookie);
441 kfree(asoc->peer.peer_random);
442 kfree(asoc->peer.peer_chunks);
443 kfree(asoc->peer.peer_hmacs);
445 /* Release the transport structures. */
446 list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
447 transport = list_entry(pos, struct sctp_transport, transports);
449 sctp_transport_free(transport);
452 asoc->peer.transport_count = 0;
454 sctp_asconf_queue_teardown(asoc);
456 /* Free pending address space being deleted */
457 if (asoc->asconf_addr_del_pending != NULL)
458 kfree(asoc->asconf_addr_del_pending);
460 /* AUTH - Free the endpoint shared keys */
461 sctp_auth_destroy_keys(&asoc->endpoint_shared_keys);
463 /* AUTH - Free the association shared key */
464 sctp_auth_key_put(asoc->asoc_shared_key);
466 sctp_association_put(asoc);
469 /* Cleanup and free up an association. */
470 static void sctp_association_destroy(struct sctp_association *asoc)
472 SCTP_ASSERT(asoc->base.dead, "Assoc is not dead", return);
474 sctp_endpoint_put(asoc->ep);
475 sock_put(asoc->base.sk);
477 if (asoc->assoc_id != 0) {
478 spin_lock_bh(&sctp_assocs_id_lock);
479 idr_remove(&sctp_assocs_id, asoc->assoc_id);
480 spin_unlock_bh(&sctp_assocs_id_lock);
483 WARN_ON(atomic_read(&asoc->rmem_alloc));
486 SCTP_DBG_OBJCNT_DEC(assoc);
489 /* Change the primary destination address for the peer. */
490 void sctp_assoc_set_primary(struct sctp_association *asoc,
491 struct sctp_transport *transport)
495 /* it's a changeover only if we already have a primary path
496 * that we are changing
498 if (asoc->peer.primary_path != NULL &&
499 asoc->peer.primary_path != transport)
502 asoc->peer.primary_path = transport;
504 /* Set a default msg_name for events. */
505 memcpy(&asoc->peer.primary_addr, &transport->ipaddr,
506 sizeof(union sctp_addr));
508 /* If the primary path is changing, assume that the
509 * user wants to use this new path.
511 if ((transport->state == SCTP_ACTIVE) ||
512 (transport->state == SCTP_UNKNOWN))
513 asoc->peer.active_path = transport;
516 * SFR-CACC algorithm:
517 * Upon the receipt of a request to change the primary
518 * destination address, on the data structure for the new
519 * primary destination, the sender MUST do the following:
521 * 1) If CHANGEOVER_ACTIVE is set, then there was a switch
522 * to this destination address earlier. The sender MUST set
523 * CYCLING_CHANGEOVER to indicate that this switch is a
524 * double switch to the same destination address.
526 * Really, only bother is we have data queued or outstanding on
529 if (!asoc->outqueue.outstanding_bytes && !asoc->outqueue.out_qlen)
532 if (transport->cacc.changeover_active)
533 transport->cacc.cycling_changeover = changeover;
535 /* 2) The sender MUST set CHANGEOVER_ACTIVE to indicate that
536 * a changeover has occurred.
538 transport->cacc.changeover_active = changeover;
540 /* 3) The sender MUST store the next TSN to be sent in
541 * next_tsn_at_change.
543 transport->cacc.next_tsn_at_change = asoc->next_tsn;
546 /* Remove a transport from an association. */
547 void sctp_assoc_rm_peer(struct sctp_association *asoc,
548 struct sctp_transport *peer)
550 struct list_head *pos;
551 struct sctp_transport *transport;
553 SCTP_DEBUG_PRINTK_IPADDR("sctp_assoc_rm_peer:association %p addr: ",
557 ntohs(peer->ipaddr.v4.sin_port));
559 /* If we are to remove the current retran_path, update it
560 * to the next peer before removing this peer from the list.
562 if (asoc->peer.retran_path == peer)
563 sctp_assoc_update_retran_path(asoc);
565 /* Remove this peer from the list. */
566 list_del_rcu(&peer->transports);
568 /* Get the first transport of asoc. */
569 pos = asoc->peer.transport_addr_list.next;
570 transport = list_entry(pos, struct sctp_transport, transports);
572 /* Update any entries that match the peer to be deleted. */
573 if (asoc->peer.primary_path == peer)
574 sctp_assoc_set_primary(asoc, transport);
575 if (asoc->peer.active_path == peer)
576 asoc->peer.active_path = transport;
577 if (asoc->peer.retran_path == peer)
578 asoc->peer.retran_path = transport;
579 if (asoc->peer.last_data_from == peer)
580 asoc->peer.last_data_from = transport;
582 /* If we remove the transport an INIT was last sent to, set it to
583 * NULL. Combined with the update of the retran path above, this
584 * will cause the next INIT to be sent to the next available
585 * transport, maintaining the cycle.
587 if (asoc->init_last_sent_to == peer)
588 asoc->init_last_sent_to = NULL;
590 /* If we remove the transport an SHUTDOWN was last sent to, set it
591 * to NULL. Combined with the update of the retran path above, this
592 * will cause the next SHUTDOWN to be sent to the next available
593 * transport, maintaining the cycle.
595 if (asoc->shutdown_last_sent_to == peer)
596 asoc->shutdown_last_sent_to = NULL;
598 /* If we remove the transport an ASCONF was last sent to, set it to
601 if (asoc->addip_last_asconf &&
602 asoc->addip_last_asconf->transport == peer)
603 asoc->addip_last_asconf->transport = NULL;
605 /* If we have something on the transmitted list, we have to
606 * save it off. The best place is the active path.
608 if (!list_empty(&peer->transmitted)) {
609 struct sctp_transport *active = asoc->peer.active_path;
610 struct sctp_chunk *ch;
612 /* Reset the transport of each chunk on this list */
613 list_for_each_entry(ch, &peer->transmitted,
615 ch->transport = NULL;
616 ch->rtt_in_progress = 0;
619 list_splice_tail_init(&peer->transmitted,
620 &active->transmitted);
622 /* Start a T3 timer here in case it wasn't running so
623 * that these migrated packets have a chance to get
626 if (!timer_pending(&active->T3_rtx_timer))
627 if (!mod_timer(&active->T3_rtx_timer,
628 jiffies + active->rto))
629 sctp_transport_hold(active);
632 asoc->peer.transport_count--;
634 sctp_transport_free(peer);
637 /* Add a transport address to an association. */
638 struct sctp_transport *sctp_assoc_add_peer(struct sctp_association *asoc,
639 const union sctp_addr *addr,
641 const int peer_state)
643 struct net *net = sock_net(asoc->base.sk);
644 struct sctp_transport *peer;
645 struct sctp_sock *sp;
648 sp = sctp_sk(asoc->base.sk);
650 /* AF_INET and AF_INET6 share common port field. */
651 port = ntohs(addr->v4.sin_port);
653 SCTP_DEBUG_PRINTK_IPADDR("sctp_assoc_add_peer:association %p addr: ",
654 " port: %d state:%d\n",
660 /* Set the port if it has not been set yet. */
661 if (0 == asoc->peer.port)
662 asoc->peer.port = port;
664 /* Check to see if this is a duplicate. */
665 peer = sctp_assoc_lookup_paddr(asoc, addr);
667 /* An UNKNOWN state is only set on transports added by
668 * user in sctp_connectx() call. Such transports should be
669 * considered CONFIRMED per RFC 4960, Section 5.4.
671 if (peer->state == SCTP_UNKNOWN) {
672 peer->state = SCTP_ACTIVE;
677 peer = sctp_transport_new(net, addr, gfp);
681 sctp_transport_set_owner(peer, asoc);
683 /* Initialize the peer's heartbeat interval based on the
684 * association configured value.
686 peer->hbinterval = asoc->hbinterval;
688 /* Set the path max_retrans. */
689 peer->pathmaxrxt = asoc->pathmaxrxt;
691 /* And the partial failure retrnas threshold */
692 peer->pf_retrans = asoc->pf_retrans;
694 /* Initialize the peer's SACK delay timeout based on the
695 * association configured value.
697 peer->sackdelay = asoc->sackdelay;
698 peer->sackfreq = asoc->sackfreq;
700 /* Enable/disable heartbeat, SACK delay, and path MTU discovery
701 * based on association setting.
703 peer->param_flags = asoc->param_flags;
705 sctp_transport_route(peer, NULL, sp);
707 /* Initialize the pmtu of the transport. */
708 if (peer->param_flags & SPP_PMTUD_DISABLE) {
710 peer->pathmtu = asoc->pathmtu;
712 peer->pathmtu = SCTP_DEFAULT_MAXSEGMENT;
715 /* If this is the first transport addr on this association,
716 * initialize the association PMTU to the peer's PMTU.
717 * If not and the current association PMTU is higher than the new
718 * peer's PMTU, reset the association PMTU to the new peer's PMTU.
721 asoc->pathmtu = min_t(int, peer->pathmtu, asoc->pathmtu);
723 asoc->pathmtu = peer->pathmtu;
725 SCTP_DEBUG_PRINTK("sctp_assoc_add_peer:association %p PMTU set to "
726 "%d\n", asoc, asoc->pathmtu);
727 peer->pmtu_pending = 0;
729 asoc->frag_point = sctp_frag_point(asoc, asoc->pathmtu);
731 /* The asoc->peer.port might not be meaningful yet, but
732 * initialize the packet structure anyway.
734 sctp_packet_init(&peer->packet, peer, asoc->base.bind_addr.port,
739 * o The initial cwnd before DATA transmission or after a sufficiently
740 * long idle period MUST be set to
741 * min(4*MTU, max(2*MTU, 4380 bytes))
743 * o The initial value of ssthresh MAY be arbitrarily high
744 * (for example, implementations MAY use the size of the
745 * receiver advertised window).
747 peer->cwnd = min(4*asoc->pathmtu, max_t(__u32, 2*asoc->pathmtu, 4380));
749 /* At this point, we may not have the receiver's advertised window,
750 * so initialize ssthresh to the default value and it will be set
751 * later when we process the INIT.
753 peer->ssthresh = SCTP_DEFAULT_MAXWINDOW;
755 peer->partial_bytes_acked = 0;
756 peer->flight_size = 0;
757 peer->burst_limited = 0;
759 /* Set the transport's RTO.initial value */
760 peer->rto = asoc->rto_initial;
761 sctp_max_rto(asoc, peer);
763 /* Set the peer's active state. */
764 peer->state = peer_state;
766 /* Attach the remote transport to our asoc. */
767 list_add_tail_rcu(&peer->transports, &asoc->peer.transport_addr_list);
768 asoc->peer.transport_count++;
770 /* If we do not yet have a primary path, set one. */
771 if (!asoc->peer.primary_path) {
772 sctp_assoc_set_primary(asoc, peer);
773 asoc->peer.retran_path = peer;
776 if (asoc->peer.active_path == asoc->peer.retran_path &&
777 peer->state != SCTP_UNCONFIRMED) {
778 asoc->peer.retran_path = peer;
784 /* Delete a transport address from an association. */
785 void sctp_assoc_del_peer(struct sctp_association *asoc,
786 const union sctp_addr *addr)
788 struct list_head *pos;
789 struct list_head *temp;
790 struct sctp_transport *transport;
792 list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
793 transport = list_entry(pos, struct sctp_transport, transports);
794 if (sctp_cmp_addr_exact(addr, &transport->ipaddr)) {
795 /* Do book keeping for removing the peer and free it. */
796 sctp_assoc_rm_peer(asoc, transport);
802 /* Lookup a transport by address. */
803 struct sctp_transport *sctp_assoc_lookup_paddr(
804 const struct sctp_association *asoc,
805 const union sctp_addr *address)
807 struct sctp_transport *t;
809 /* Cycle through all transports searching for a peer address. */
811 list_for_each_entry(t, &asoc->peer.transport_addr_list,
813 if (sctp_cmp_addr_exact(address, &t->ipaddr))
820 /* Remove all transports except a give one */
821 void sctp_assoc_del_nonprimary_peers(struct sctp_association *asoc,
822 struct sctp_transport *primary)
824 struct sctp_transport *temp;
825 struct sctp_transport *t;
827 list_for_each_entry_safe(t, temp, &asoc->peer.transport_addr_list,
829 /* if the current transport is not the primary one, delete it */
831 sctp_assoc_rm_peer(asoc, t);
835 /* Engage in transport control operations.
836 * Mark the transport up or down and send a notification to the user.
837 * Select and update the new active and retran paths.
839 void sctp_assoc_control_transport(struct sctp_association *asoc,
840 struct sctp_transport *transport,
841 sctp_transport_cmd_t command,
842 sctp_sn_error_t error)
844 struct sctp_transport *t = NULL;
845 struct sctp_transport *first;
846 struct sctp_transport *second;
847 struct sctp_ulpevent *event;
848 struct sockaddr_storage addr;
850 bool ulp_notify = true;
852 /* Record the transition on the transport. */
854 case SCTP_TRANSPORT_UP:
855 /* If we are moving from UNCONFIRMED state due
856 * to heartbeat success, report the SCTP_ADDR_CONFIRMED
857 * state to the user, otherwise report SCTP_ADDR_AVAILABLE.
859 if (SCTP_UNCONFIRMED == transport->state &&
860 SCTP_HEARTBEAT_SUCCESS == error)
861 spc_state = SCTP_ADDR_CONFIRMED;
863 spc_state = SCTP_ADDR_AVAILABLE;
864 /* Don't inform ULP about transition from PF to
865 * active state and set cwnd to 1, see SCTP
866 * Quick failover draft section 5.1, point 5
868 if (transport->state == SCTP_PF) {
872 transport->state = SCTP_ACTIVE;
875 case SCTP_TRANSPORT_DOWN:
876 /* If the transport was never confirmed, do not transition it
877 * to inactive state. Also, release the cached route since
878 * there may be a better route next time.
880 if (transport->state != SCTP_UNCONFIRMED)
881 transport->state = SCTP_INACTIVE;
883 dst_release(transport->dst);
884 transport->dst = NULL;
887 spc_state = SCTP_ADDR_UNREACHABLE;
890 case SCTP_TRANSPORT_PF:
891 transport->state = SCTP_PF;
899 /* Generate and send a SCTP_PEER_ADDR_CHANGE notification to the
903 memset(&addr, 0, sizeof(struct sockaddr_storage));
904 memcpy(&addr, &transport->ipaddr,
905 transport->af_specific->sockaddr_len);
906 event = sctp_ulpevent_make_peer_addr_change(asoc, &addr,
907 0, spc_state, error, GFP_ATOMIC);
909 sctp_ulpq_tail_event(&asoc->ulpq, event);
912 /* Select new active and retran paths. */
914 /* Look for the two most recently used active transports.
916 * This code produces the wrong ordering whenever jiffies
917 * rolls over, but we still get usable transports, so we don't
920 first = NULL; second = NULL;
922 list_for_each_entry(t, &asoc->peer.transport_addr_list,
925 if ((t->state == SCTP_INACTIVE) ||
926 (t->state == SCTP_UNCONFIRMED) ||
927 (t->state == SCTP_PF))
929 if (!first || t->last_time_heard > first->last_time_heard) {
933 if (!second || t->last_time_heard > second->last_time_heard)
937 /* RFC 2960 6.4 Multi-Homed SCTP Endpoints
939 * By default, an endpoint should always transmit to the
940 * primary path, unless the SCTP user explicitly specifies the
941 * destination transport address (and possibly source
942 * transport address) to use.
944 * [If the primary is active but not most recent, bump the most
945 * recently used transport.]
947 if (((asoc->peer.primary_path->state == SCTP_ACTIVE) ||
948 (asoc->peer.primary_path->state == SCTP_UNKNOWN)) &&
949 first != asoc->peer.primary_path) {
951 first = asoc->peer.primary_path;
954 /* If we failed to find a usable transport, just camp on the
955 * primary, even if it is inactive.
958 first = asoc->peer.primary_path;
959 second = asoc->peer.primary_path;
962 /* Set the active and retran transports. */
963 asoc->peer.active_path = first;
964 asoc->peer.retran_path = second;
967 /* Hold a reference to an association. */
968 void sctp_association_hold(struct sctp_association *asoc)
970 atomic_inc(&asoc->base.refcnt);
973 /* Release a reference to an association and cleanup
974 * if there are no more references.
976 void sctp_association_put(struct sctp_association *asoc)
978 if (atomic_dec_and_test(&asoc->base.refcnt))
979 sctp_association_destroy(asoc);
982 /* Allocate the next TSN, Transmission Sequence Number, for the given
985 __u32 sctp_association_get_next_tsn(struct sctp_association *asoc)
987 /* From Section 1.6 Serial Number Arithmetic:
988 * Transmission Sequence Numbers wrap around when they reach
989 * 2**32 - 1. That is, the next TSN a DATA chunk MUST use
990 * after transmitting TSN = 2*32 - 1 is TSN = 0.
992 __u32 retval = asoc->next_tsn;
999 /* Compare two addresses to see if they match. Wildcard addresses
1000 * only match themselves.
1002 int sctp_cmp_addr_exact(const union sctp_addr *ss1,
1003 const union sctp_addr *ss2)
1007 af = sctp_get_af_specific(ss1->sa.sa_family);
1011 return af->cmp_addr(ss1, ss2);
1014 /* Return an ecne chunk to get prepended to a packet.
1015 * Note: We are sly and return a shared, prealloced chunk. FIXME:
1016 * No we don't, but we could/should.
1018 struct sctp_chunk *sctp_get_ecne_prepend(struct sctp_association *asoc)
1020 struct sctp_chunk *chunk;
1022 /* Send ECNE if needed.
1023 * Not being able to allocate a chunk here is not deadly.
1025 if (asoc->need_ecne)
1026 chunk = sctp_make_ecne(asoc, asoc->last_ecne_tsn);
1034 * Find which transport this TSN was sent on.
1036 struct sctp_transport *sctp_assoc_lookup_tsn(struct sctp_association *asoc,
1039 struct sctp_transport *active;
1040 struct sctp_transport *match;
1041 struct sctp_transport *transport;
1042 struct sctp_chunk *chunk;
1043 __be32 key = htonl(tsn);
1048 * FIXME: In general, find a more efficient data structure for
1053 * The general strategy is to search each transport's transmitted
1054 * list. Return which transport this TSN lives on.
1056 * Let's be hopeful and check the active_path first.
1057 * Another optimization would be to know if there is only one
1058 * outbound path and not have to look for the TSN at all.
1062 active = asoc->peer.active_path;
1064 list_for_each_entry(chunk, &active->transmitted,
1067 if (key == chunk->subh.data_hdr->tsn) {
1073 /* If not found, go search all the other transports. */
1074 list_for_each_entry(transport, &asoc->peer.transport_addr_list,
1077 if (transport == active)
1079 list_for_each_entry(chunk, &transport->transmitted,
1081 if (key == chunk->subh.data_hdr->tsn) {
1091 /* Is this the association we are looking for? */
1092 struct sctp_transport *sctp_assoc_is_match(struct sctp_association *asoc,
1094 const union sctp_addr *laddr,
1095 const union sctp_addr *paddr)
1097 struct sctp_transport *transport;
1099 if ((htons(asoc->base.bind_addr.port) == laddr->v4.sin_port) &&
1100 (htons(asoc->peer.port) == paddr->v4.sin_port) &&
1101 net_eq(sock_net(asoc->base.sk), net)) {
1102 transport = sctp_assoc_lookup_paddr(asoc, paddr);
1106 if (sctp_bind_addr_match(&asoc->base.bind_addr, laddr,
1107 sctp_sk(asoc->base.sk)))
1116 /* Do delayed input processing. This is scheduled by sctp_rcv(). */
1117 static void sctp_assoc_bh_rcv(struct work_struct *work)
1119 struct sctp_association *asoc =
1120 container_of(work, struct sctp_association,
1121 base.inqueue.immediate);
1122 struct net *net = sock_net(asoc->base.sk);
1123 struct sctp_endpoint *ep;
1124 struct sctp_chunk *chunk;
1125 struct sctp_inq *inqueue;
1127 sctp_subtype_t subtype;
1130 /* The association should be held so we should be safe. */
1133 inqueue = &asoc->base.inqueue;
1134 sctp_association_hold(asoc);
1135 while (NULL != (chunk = sctp_inq_pop(inqueue))) {
1136 state = asoc->state;
1137 subtype = SCTP_ST_CHUNK(chunk->chunk_hdr->type);
1139 /* SCTP-AUTH, Section 6.3:
1140 * The receiver has a list of chunk types which it expects
1141 * to be received only after an AUTH-chunk. This list has
1142 * been sent to the peer during the association setup. It
1143 * MUST silently discard these chunks if they are not placed
1144 * after an AUTH chunk in the packet.
1146 if (sctp_auth_recv_cid(subtype.chunk, asoc) && !chunk->auth)
1149 /* Remember where the last DATA chunk came from so we
1150 * know where to send the SACK.
1152 if (sctp_chunk_is_data(chunk))
1153 asoc->peer.last_data_from = chunk->transport;
1155 SCTP_INC_STATS(net, SCTP_MIB_INCTRLCHUNKS);
1156 asoc->stats.ictrlchunks++;
1157 if (chunk->chunk_hdr->type == SCTP_CID_SACK)
1158 asoc->stats.isacks++;
1161 if (chunk->transport)
1162 chunk->transport->last_time_heard = jiffies;
1164 /* Run through the state machine. */
1165 error = sctp_do_sm(net, SCTP_EVENT_T_CHUNK, subtype,
1166 state, ep, asoc, chunk, GFP_ATOMIC);
1168 /* Check to see if the association is freed in response to
1169 * the incoming chunk. If so, get out of the while loop.
1171 if (asoc->base.dead)
1174 /* If there is an error on chunk, discard this packet. */
1176 chunk->pdiscard = 1;
1178 sctp_association_put(asoc);
1181 /* This routine moves an association from its old sk to a new sk. */
1182 void sctp_assoc_migrate(struct sctp_association *assoc, struct sock *newsk)
1184 struct sctp_sock *newsp = sctp_sk(newsk);
1185 struct sock *oldsk = assoc->base.sk;
1187 /* Delete the association from the old endpoint's list of
1190 list_del_init(&assoc->asocs);
1192 /* Decrement the backlog value for a TCP-style socket. */
1193 if (sctp_style(oldsk, TCP))
1194 oldsk->sk_ack_backlog--;
1196 /* Release references to the old endpoint and the sock. */
1197 sctp_endpoint_put(assoc->ep);
1198 sock_put(assoc->base.sk);
1200 /* Get a reference to the new endpoint. */
1201 assoc->ep = newsp->ep;
1202 sctp_endpoint_hold(assoc->ep);
1204 /* Get a reference to the new sock. */
1205 assoc->base.sk = newsk;
1206 sock_hold(assoc->base.sk);
1208 /* Add the association to the new endpoint's list of associations. */
1209 sctp_endpoint_add_asoc(newsp->ep, assoc);
1212 /* Update an association (possibly from unexpected COOKIE-ECHO processing). */
1213 void sctp_assoc_update(struct sctp_association *asoc,
1214 struct sctp_association *new)
1216 struct sctp_transport *trans;
1217 struct list_head *pos, *temp;
1219 /* Copy in new parameters of peer. */
1221 asoc->peer.rwnd = new->peer.rwnd;
1222 asoc->peer.sack_needed = new->peer.sack_needed;
1223 asoc->peer.i = new->peer.i;
1224 sctp_tsnmap_init(&asoc->peer.tsn_map, SCTP_TSN_MAP_INITIAL,
1225 asoc->peer.i.initial_tsn, GFP_ATOMIC);
1227 /* Remove any peer addresses not present in the new association. */
1228 list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
1229 trans = list_entry(pos, struct sctp_transport, transports);
1230 if (!sctp_assoc_lookup_paddr(new, &trans->ipaddr)) {
1231 sctp_assoc_rm_peer(asoc, trans);
1235 if (asoc->state >= SCTP_STATE_ESTABLISHED)
1236 sctp_transport_reset(trans);
1239 /* If the case is A (association restart), use
1240 * initial_tsn as next_tsn. If the case is B, use
1241 * current next_tsn in case data sent to peer
1242 * has been discarded and needs retransmission.
1244 if (asoc->state >= SCTP_STATE_ESTABLISHED) {
1245 asoc->next_tsn = new->next_tsn;
1246 asoc->ctsn_ack_point = new->ctsn_ack_point;
1247 asoc->adv_peer_ack_point = new->adv_peer_ack_point;
1249 /* Reinitialize SSN for both local streams
1250 * and peer's streams.
1252 sctp_ssnmap_clear(asoc->ssnmap);
1254 /* Flush the ULP reassembly and ordered queue.
1255 * Any data there will now be stale and will
1258 sctp_ulpq_flush(&asoc->ulpq);
1260 /* reset the overall association error count so
1261 * that the restarted association doesn't get torn
1262 * down on the next retransmission timer.
1264 asoc->overall_error_count = 0;
1267 /* Add any peer addresses from the new association. */
1268 list_for_each_entry(trans, &new->peer.transport_addr_list,
1270 if (!sctp_assoc_lookup_paddr(asoc, &trans->ipaddr))
1271 sctp_assoc_add_peer(asoc, &trans->ipaddr,
1272 GFP_ATOMIC, trans->state);
1275 asoc->ctsn_ack_point = asoc->next_tsn - 1;
1276 asoc->adv_peer_ack_point = asoc->ctsn_ack_point;
1277 if (!asoc->ssnmap) {
1278 /* Move the ssnmap. */
1279 asoc->ssnmap = new->ssnmap;
1283 if (!asoc->assoc_id) {
1284 /* get a new association id since we don't have one
1287 sctp_assoc_set_id(asoc, GFP_ATOMIC);
1291 /* SCTP-AUTH: Save the peer parameters from the new assocaitions
1292 * and also move the association shared keys over
1294 kfree(asoc->peer.peer_random);
1295 asoc->peer.peer_random = new->peer.peer_random;
1296 new->peer.peer_random = NULL;
1298 kfree(asoc->peer.peer_chunks);
1299 asoc->peer.peer_chunks = new->peer.peer_chunks;
1300 new->peer.peer_chunks = NULL;
1302 kfree(asoc->peer.peer_hmacs);
1303 asoc->peer.peer_hmacs = new->peer.peer_hmacs;
1304 new->peer.peer_hmacs = NULL;
1306 sctp_auth_key_put(asoc->asoc_shared_key);
1307 sctp_auth_asoc_init_active_key(asoc, GFP_ATOMIC);
1310 /* Update the retran path for sending a retransmitted packet.
1311 * Round-robin through the active transports, else round-robin
1312 * through the inactive transports as this is the next best thing
1315 void sctp_assoc_update_retran_path(struct sctp_association *asoc)
1317 struct sctp_transport *t, *next;
1318 struct list_head *head = &asoc->peer.transport_addr_list;
1319 struct list_head *pos;
1321 if (asoc->peer.transport_count == 1)
1324 /* Find the next transport in a round-robin fashion. */
1325 t = asoc->peer.retran_path;
1326 pos = &t->transports;
1330 /* Skip the head. */
1331 if (pos->next == head)
1336 t = list_entry(pos, struct sctp_transport, transports);
1338 /* We have exhausted the list, but didn't find any
1339 * other active transports. If so, use the next
1342 if (t == asoc->peer.retran_path) {
1347 /* Try to find an active transport. */
1349 if ((t->state == SCTP_ACTIVE) ||
1350 (t->state == SCTP_UNKNOWN)) {
1353 /* Keep track of the next transport in case
1354 * we don't find any active transport.
1356 if (t->state != SCTP_UNCONFIRMED && !next)
1362 asoc->peer.retran_path = t;
1364 t = asoc->peer.retran_path;
1366 SCTP_DEBUG_PRINTK_IPADDR("sctp_assoc_update_retran_path:association"
1371 ntohs(t->ipaddr.v4.sin_port));
1374 /* Choose the transport for sending retransmit packet. */
1375 struct sctp_transport *sctp_assoc_choose_alter_transport(
1376 struct sctp_association *asoc, struct sctp_transport *last_sent_to)
1378 /* If this is the first time packet is sent, use the active path,
1379 * else use the retran path. If the last packet was sent over the
1380 * retran path, update the retran path and use it.
1383 return asoc->peer.active_path;
1385 if (last_sent_to == asoc->peer.retran_path)
1386 sctp_assoc_update_retran_path(asoc);
1387 return asoc->peer.retran_path;
1391 /* Update the association's pmtu and frag_point by going through all the
1392 * transports. This routine is called when a transport's PMTU has changed.
1394 void sctp_assoc_sync_pmtu(struct sock *sk, struct sctp_association *asoc)
1396 struct sctp_transport *t;
1402 /* Get the lowest pmtu of all the transports. */
1403 list_for_each_entry(t, &asoc->peer.transport_addr_list,
1405 if (t->pmtu_pending && t->dst) {
1406 sctp_transport_update_pmtu(sk, t, dst_mtu(t->dst));
1407 t->pmtu_pending = 0;
1409 if (!pmtu || (t->pathmtu < pmtu))
1414 asoc->pathmtu = pmtu;
1415 asoc->frag_point = sctp_frag_point(asoc, pmtu);
1418 SCTP_DEBUG_PRINTK("%s: asoc:%p, pmtu:%d, frag_point:%d\n",
1419 __func__, asoc, asoc->pathmtu, asoc->frag_point);
1422 /* Should we send a SACK to update our peer? */
1423 static inline int sctp_peer_needs_update(struct sctp_association *asoc)
1425 struct net *net = sock_net(asoc->base.sk);
1426 switch (asoc->state) {
1427 case SCTP_STATE_ESTABLISHED:
1428 case SCTP_STATE_SHUTDOWN_PENDING:
1429 case SCTP_STATE_SHUTDOWN_RECEIVED:
1430 case SCTP_STATE_SHUTDOWN_SENT:
1431 if ((asoc->rwnd > asoc->a_rwnd) &&
1432 ((asoc->rwnd - asoc->a_rwnd) >= max_t(__u32,
1433 (asoc->base.sk->sk_rcvbuf >> net->sctp.rwnd_upd_shift),
1443 /* Increase asoc's rwnd by len and send any window update SACK if needed. */
1444 void sctp_assoc_rwnd_increase(struct sctp_association *asoc, unsigned int len)
1446 struct sctp_chunk *sack;
1447 struct timer_list *timer;
1449 if (asoc->rwnd_over) {
1450 if (asoc->rwnd_over >= len) {
1451 asoc->rwnd_over -= len;
1453 asoc->rwnd += (len - asoc->rwnd_over);
1454 asoc->rwnd_over = 0;
1460 /* If we had window pressure, start recovering it
1461 * once our rwnd had reached the accumulated pressure
1462 * threshold. The idea is to recover slowly, but up
1463 * to the initial advertised window.
1465 if (asoc->rwnd_press && asoc->rwnd >= asoc->rwnd_press) {
1466 int change = min(asoc->pathmtu, asoc->rwnd_press);
1467 asoc->rwnd += change;
1468 asoc->rwnd_press -= change;
1471 SCTP_DEBUG_PRINTK("%s: asoc %p rwnd increased by %d to (%u, %u) "
1472 "- %u\n", __func__, asoc, len, asoc->rwnd,
1473 asoc->rwnd_over, asoc->a_rwnd);
1475 /* Send a window update SACK if the rwnd has increased by at least the
1476 * minimum of the association's PMTU and half of the receive buffer.
1477 * The algorithm used is similar to the one described in
1478 * Section 4.2.3.3 of RFC 1122.
1480 if (sctp_peer_needs_update(asoc)) {
1481 asoc->a_rwnd = asoc->rwnd;
1482 SCTP_DEBUG_PRINTK("%s: Sending window update SACK- asoc: %p "
1483 "rwnd: %u a_rwnd: %u\n", __func__,
1484 asoc, asoc->rwnd, asoc->a_rwnd);
1485 sack = sctp_make_sack(asoc);
1489 asoc->peer.sack_needed = 0;
1491 sctp_outq_tail(&asoc->outqueue, sack);
1493 /* Stop the SACK timer. */
1494 timer = &asoc->timers[SCTP_EVENT_TIMEOUT_SACK];
1495 if (del_timer(timer))
1496 sctp_association_put(asoc);
1500 /* Decrease asoc's rwnd by len. */
1501 void sctp_assoc_rwnd_decrease(struct sctp_association *asoc, unsigned int len)
1506 SCTP_ASSERT(asoc->rwnd, "rwnd zero", return);
1507 SCTP_ASSERT(!asoc->rwnd_over, "rwnd_over not zero", return);
1509 if (asoc->ep->rcvbuf_policy)
1510 rx_count = atomic_read(&asoc->rmem_alloc);
1512 rx_count = atomic_read(&asoc->base.sk->sk_rmem_alloc);
1514 /* If we've reached or overflowed our receive buffer, announce
1515 * a 0 rwnd if rwnd would still be positive. Store the
1516 * the pottential pressure overflow so that the window can be restored
1517 * back to original value.
1519 if (rx_count >= asoc->base.sk->sk_rcvbuf)
1522 if (asoc->rwnd >= len) {
1525 asoc->rwnd_press += asoc->rwnd;
1529 asoc->rwnd_over = len - asoc->rwnd;
1532 SCTP_DEBUG_PRINTK("%s: asoc %p rwnd decreased by %d to (%u, %u, %u)\n",
1533 __func__, asoc, len, asoc->rwnd,
1534 asoc->rwnd_over, asoc->rwnd_press);
1537 /* Build the bind address list for the association based on info from the
1538 * local endpoint and the remote peer.
1540 int sctp_assoc_set_bind_addr_from_ep(struct sctp_association *asoc,
1541 sctp_scope_t scope, gfp_t gfp)
1545 /* Use scoping rules to determine the subset of addresses from
1548 flags = (PF_INET6 == asoc->base.sk->sk_family) ? SCTP_ADDR6_ALLOWED : 0;
1549 if (asoc->peer.ipv4_address)
1550 flags |= SCTP_ADDR4_PEERSUPP;
1551 if (asoc->peer.ipv6_address)
1552 flags |= SCTP_ADDR6_PEERSUPP;
1554 return sctp_bind_addr_copy(sock_net(asoc->base.sk),
1555 &asoc->base.bind_addr,
1556 &asoc->ep->base.bind_addr,
1560 /* Build the association's bind address list from the cookie. */
1561 int sctp_assoc_set_bind_addr_from_cookie(struct sctp_association *asoc,
1562 struct sctp_cookie *cookie,
1565 int var_size2 = ntohs(cookie->peer_init->chunk_hdr.length);
1566 int var_size3 = cookie->raw_addr_list_len;
1567 __u8 *raw = (__u8 *)cookie->peer_init + var_size2;
1569 return sctp_raw_to_bind_addrs(&asoc->base.bind_addr, raw, var_size3,
1570 asoc->ep->base.bind_addr.port, gfp);
1573 /* Lookup laddr in the bind address list of an association. */
1574 int sctp_assoc_lookup_laddr(struct sctp_association *asoc,
1575 const union sctp_addr *laddr)
1579 if ((asoc->base.bind_addr.port == ntohs(laddr->v4.sin_port)) &&
1580 sctp_bind_addr_match(&asoc->base.bind_addr, laddr,
1581 sctp_sk(asoc->base.sk)))
1587 /* Set an association id for a given association */
1588 int sctp_assoc_set_id(struct sctp_association *asoc, gfp_t gfp)
1590 bool preload = gfp & __GFP_WAIT;
1593 /* If the id is already assigned, keep it. */
1599 spin_lock_bh(&sctp_assocs_id_lock);
1600 /* 0 is not a valid id, idr_low is always >= 1 */
1601 ret = idr_alloc(&sctp_assocs_id, asoc, idr_low, 0, GFP_NOWAIT);
1604 if (idr_low == INT_MAX)
1607 spin_unlock_bh(&sctp_assocs_id_lock);
1613 asoc->assoc_id = (sctp_assoc_t)ret;
1617 /* Free the ASCONF queue */
1618 static void sctp_assoc_free_asconf_queue(struct sctp_association *asoc)
1620 struct sctp_chunk *asconf;
1621 struct sctp_chunk *tmp;
1623 list_for_each_entry_safe(asconf, tmp, &asoc->addip_chunk_list, list) {
1624 list_del_init(&asconf->list);
1625 sctp_chunk_free(asconf);
1629 /* Free asconf_ack cache */
1630 static void sctp_assoc_free_asconf_acks(struct sctp_association *asoc)
1632 struct sctp_chunk *ack;
1633 struct sctp_chunk *tmp;
1635 list_for_each_entry_safe(ack, tmp, &asoc->asconf_ack_list,
1637 list_del_init(&ack->transmitted_list);
1638 sctp_chunk_free(ack);
1642 /* Clean up the ASCONF_ACK queue */
1643 void sctp_assoc_clean_asconf_ack_cache(const struct sctp_association *asoc)
1645 struct sctp_chunk *ack;
1646 struct sctp_chunk *tmp;
1648 /* We can remove all the entries from the queue up to
1649 * the "Peer-Sequence-Number".
1651 list_for_each_entry_safe(ack, tmp, &asoc->asconf_ack_list,
1653 if (ack->subh.addip_hdr->serial ==
1654 htonl(asoc->peer.addip_serial))
1657 list_del_init(&ack->transmitted_list);
1658 sctp_chunk_free(ack);
1662 /* Find the ASCONF_ACK whose serial number matches ASCONF */
1663 struct sctp_chunk *sctp_assoc_lookup_asconf_ack(
1664 const struct sctp_association *asoc,
1667 struct sctp_chunk *ack;
1669 /* Walk through the list of cached ASCONF-ACKs and find the
1670 * ack chunk whose serial number matches that of the request.
1672 list_for_each_entry(ack, &asoc->asconf_ack_list, transmitted_list) {
1673 if (ack->subh.addip_hdr->serial == serial) {
1674 sctp_chunk_hold(ack);
1682 void sctp_asconf_queue_teardown(struct sctp_association *asoc)
1684 /* Free any cached ASCONF_ACK chunk. */
1685 sctp_assoc_free_asconf_acks(asoc);
1687 /* Free the ASCONF queue. */
1688 sctp_assoc_free_asconf_queue(asoc);
1690 /* Free any cached ASCONF chunk. */
1691 if (asoc->addip_last_asconf)
1692 sctp_chunk_free(asoc->addip_last_asconf);