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;
116 /* Set the association max_retrans and RTO values from the
119 asoc
->max_retrans
= sp
->assocparams
.sasoc_asocmaxrxt
;
120 asoc
->rto_initial
= msecs_to_jiffies(sp
->rtoinfo
.srto_initial
);
121 asoc
->rto_max
= msecs_to_jiffies(sp
->rtoinfo
.srto_max
);
122 asoc
->rto_min
= msecs_to_jiffies(sp
->rtoinfo
.srto_min
);
124 asoc
->overall_error_count
= 0;
126 /* Initialize the association's heartbeat interval based on the
127 * sock configured value.
129 asoc
->hbinterval
= msecs_to_jiffies(sp
->hbinterval
);
131 /* Initialize path max retrans value. */
132 asoc
->pathmaxrxt
= sp
->pathmaxrxt
;
134 /* Initialize default path MTU. */
135 asoc
->pathmtu
= sp
->pathmtu
;
137 /* Set association default SACK delay */
138 asoc
->sackdelay
= msecs_to_jiffies(sp
->sackdelay
);
139 asoc
->sackfreq
= sp
->sackfreq
;
141 /* Set the association default flags controlling
142 * Heartbeat, SACK delay, and Path MTU Discovery.
144 asoc
->param_flags
= sp
->param_flags
;
146 /* Initialize the maximum mumber of new data packets that can be sent
149 asoc
->max_burst
= sp
->max_burst
;
151 /* initialize association timers */
152 asoc
->timeouts
[SCTP_EVENT_TIMEOUT_NONE
] = 0;
153 asoc
->timeouts
[SCTP_EVENT_TIMEOUT_T1_COOKIE
] = asoc
->rto_initial
;
154 asoc
->timeouts
[SCTP_EVENT_TIMEOUT_T1_INIT
] = asoc
->rto_initial
;
155 asoc
->timeouts
[SCTP_EVENT_TIMEOUT_T2_SHUTDOWN
] = asoc
->rto_initial
;
156 asoc
->timeouts
[SCTP_EVENT_TIMEOUT_T3_RTX
] = 0;
157 asoc
->timeouts
[SCTP_EVENT_TIMEOUT_T4_RTO
] = 0;
159 /* sctpimpguide Section 2.12.2
160 * If the 'T5-shutdown-guard' timer is used, it SHOULD be set to the
161 * recommended value of 5 times 'RTO.Max'.
163 asoc
->timeouts
[SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD
]
166 asoc
->timeouts
[SCTP_EVENT_TIMEOUT_HEARTBEAT
] = 0;
167 asoc
->timeouts
[SCTP_EVENT_TIMEOUT_SACK
] = asoc
->sackdelay
;
168 asoc
->timeouts
[SCTP_EVENT_TIMEOUT_AUTOCLOSE
] =
171 /* Initilizes the timers */
172 for (i
= SCTP_EVENT_TIMEOUT_NONE
; i
< SCTP_NUM_TIMEOUT_TYPES
; ++i
)
173 setup_timer(&asoc
->timers
[i
], sctp_timer_events
[i
],
174 (unsigned long)asoc
);
176 /* Pull default initialization values from the sock options.
177 * Note: This assumes that the values have already been
178 * validated in the sock.
180 asoc
->c
.sinit_max_instreams
= sp
->initmsg
.sinit_max_instreams
;
181 asoc
->c
.sinit_num_ostreams
= sp
->initmsg
.sinit_num_ostreams
;
182 asoc
->max_init_attempts
= sp
->initmsg
.sinit_max_attempts
;
184 asoc
->max_init_timeo
=
185 msecs_to_jiffies(sp
->initmsg
.sinit_max_init_timeo
);
187 /* Allocate storage for the ssnmap after the inbound and outbound
188 * streams have been negotiated during Init.
192 /* Set the local window size for receive.
193 * This is also the rcvbuf space per association.
194 * RFC 6 - A SCTP receiver MUST be able to receive a minimum of
195 * 1500 bytes in one SCTP packet.
197 if ((sk
->sk_rcvbuf
/2) < SCTP_DEFAULT_MINWINDOW
)
198 asoc
->rwnd
= SCTP_DEFAULT_MINWINDOW
;
200 asoc
->rwnd
= sk
->sk_rcvbuf
/2;
202 asoc
->a_rwnd
= asoc
->rwnd
;
205 asoc
->rwnd_press
= 0;
207 /* Use my own max window until I learn something better. */
208 asoc
->peer
.rwnd
= SCTP_DEFAULT_MAXWINDOW
;
210 /* Set the sndbuf size for transmit. */
211 asoc
->sndbuf_used
= 0;
213 /* Initialize the receive memory counter */
214 atomic_set(&asoc
->rmem_alloc
, 0);
216 init_waitqueue_head(&asoc
->wait
);
218 asoc
->c
.my_vtag
= sctp_generate_tag(ep
);
219 asoc
->peer
.i
.init_tag
= 0; /* INIT needs a vtag of 0. */
220 asoc
->c
.peer_vtag
= 0;
222 asoc
->c
.peer_ttag
= 0;
223 asoc
->c
.my_port
= ep
->base
.bind_addr
.port
;
225 asoc
->c
.initial_tsn
= sctp_generate_tsn(ep
);
227 asoc
->next_tsn
= asoc
->c
.initial_tsn
;
229 asoc
->ctsn_ack_point
= asoc
->next_tsn
- 1;
230 asoc
->adv_peer_ack_point
= asoc
->ctsn_ack_point
;
231 asoc
->highest_sacked
= asoc
->ctsn_ack_point
;
232 asoc
->last_cwr_tsn
= asoc
->ctsn_ack_point
;
233 asoc
->unack_data
= 0;
235 /* ADDIP Section 4.1 Asconf Chunk Procedures
237 * When an endpoint has an ASCONF signaled change to be sent to the
238 * remote endpoint it should do the following:
240 * A2) a serial number should be assigned to the chunk. The serial
241 * number SHOULD be a monotonically increasing number. The serial
242 * numbers SHOULD be initialized at the start of the
243 * association to the same value as the initial TSN.
245 asoc
->addip_serial
= asoc
->c
.initial_tsn
;
247 INIT_LIST_HEAD(&asoc
->addip_chunk_list
);
248 INIT_LIST_HEAD(&asoc
->asconf_ack_list
);
250 /* Make an empty list of remote transport addresses. */
251 INIT_LIST_HEAD(&asoc
->peer
.transport_addr_list
);
252 asoc
->peer
.transport_count
= 0;
254 /* RFC 2960 5.1 Normal Establishment of an Association
256 * After the reception of the first data chunk in an
257 * association the endpoint must immediately respond with a
258 * sack to acknowledge the data chunk. Subsequent
259 * acknowledgements should be done as described in Section
262 * [We implement this by telling a new association that it
263 * already received one packet.]
265 asoc
->peer
.sack_needed
= 1;
266 asoc
->peer
.sack_cnt
= 0;
268 /* Assume that the peer will tell us if he recognizes ASCONF
269 * as part of INIT exchange.
270 * The sctp_addip_noauth option is there for backward compatibilty
271 * and will revert old behavior.
273 asoc
->peer
.asconf_capable
= 0;
274 if (sctp_addip_noauth
)
275 asoc
->peer
.asconf_capable
= 1;
277 /* Create an input queue. */
278 sctp_inq_init(&asoc
->base
.inqueue
);
279 sctp_inq_set_th_handler(&asoc
->base
.inqueue
, sctp_assoc_bh_rcv
);
281 /* Create an output queue. */
282 sctp_outq_init(asoc
, &asoc
->outqueue
);
284 if (!sctp_ulpq_init(&asoc
->ulpq
, asoc
))
287 memset(&asoc
->peer
.tsn_map
, 0, sizeof(struct sctp_tsnmap
));
293 /* Assume that peer would support both address types unless we are
296 asoc
->peer
.ipv4_address
= 1;
297 if (asoc
->base
.sk
->sk_family
== PF_INET6
)
298 asoc
->peer
.ipv6_address
= 1;
299 INIT_LIST_HEAD(&asoc
->asocs
);
301 asoc
->autoclose
= sp
->autoclose
;
303 asoc
->default_stream
= sp
->default_stream
;
304 asoc
->default_ppid
= sp
->default_ppid
;
305 asoc
->default_flags
= sp
->default_flags
;
306 asoc
->default_context
= sp
->default_context
;
307 asoc
->default_timetolive
= sp
->default_timetolive
;
308 asoc
->default_rcv_context
= sp
->default_rcv_context
;
310 /* AUTH related initializations */
311 INIT_LIST_HEAD(&asoc
->endpoint_shared_keys
);
312 err
= sctp_auth_asoc_copy_shkeys(ep
, asoc
, gfp
);
316 asoc
->active_key_id
= ep
->active_key_id
;
317 asoc
->asoc_shared_key
= NULL
;
319 asoc
->default_hmac_id
= 0;
320 /* Save the hmacs and chunks list into this association */
321 if (ep
->auth_hmacs_list
)
322 memcpy(asoc
->c
.auth_hmacs
, ep
->auth_hmacs_list
,
323 ntohs(ep
->auth_hmacs_list
->param_hdr
.length
));
324 if (ep
->auth_chunk_list
)
325 memcpy(asoc
->c
.auth_chunks
, ep
->auth_chunk_list
,
326 ntohs(ep
->auth_chunk_list
->param_hdr
.length
));
328 /* Get the AUTH random number for this association */
329 p
= (sctp_paramhdr_t
*)asoc
->c
.auth_random
;
330 p
->type
= SCTP_PARAM_RANDOM
;
331 p
->length
= htons(sizeof(sctp_paramhdr_t
) + SCTP_AUTH_RANDOM_LENGTH
);
332 get_random_bytes(p
+1, SCTP_AUTH_RANDOM_LENGTH
);
337 sctp_endpoint_put(asoc
->ep
);
338 sock_put(asoc
->base
.sk
);
342 /* Allocate and initialize a new association */
343 struct sctp_association
*sctp_association_new(const struct sctp_endpoint
*ep
,
344 const struct sock
*sk
,
348 struct sctp_association
*asoc
;
350 asoc
= t_new(struct sctp_association
, gfp
);
354 if (!sctp_association_init(asoc
, ep
, sk
, scope
, gfp
))
357 asoc
->base
.malloced
= 1;
358 SCTP_DBG_OBJCNT_INC(assoc
);
359 SCTP_DEBUG_PRINTK("Created asoc %p\n", asoc
);
369 /* Free this association if possible. There may still be users, so
370 * the actual deallocation may be delayed.
372 void sctp_association_free(struct sctp_association
*asoc
)
374 struct sock
*sk
= asoc
->base
.sk
;
375 struct sctp_transport
*transport
;
376 struct list_head
*pos
, *temp
;
379 /* Only real associations count against the endpoint, so
380 * don't bother for if this is a temporary association.
383 list_del(&asoc
->asocs
);
385 /* Decrement the backlog value for a TCP-style listening
388 if (sctp_style(sk
, TCP
) && sctp_sstate(sk
, LISTENING
))
389 sk
->sk_ack_backlog
--;
392 /* Mark as dead, so other users can know this structure is
397 /* Dispose of any data lying around in the outqueue. */
398 sctp_outq_free(&asoc
->outqueue
);
400 /* Dispose of any pending messages for the upper layer. */
401 sctp_ulpq_free(&asoc
->ulpq
);
403 /* Dispose of any pending chunks on the inqueue. */
404 sctp_inq_free(&asoc
->base
.inqueue
);
406 sctp_tsnmap_free(&asoc
->peer
.tsn_map
);
408 /* Free ssnmap storage. */
409 sctp_ssnmap_free(asoc
->ssnmap
);
411 /* Clean up the bound address list. */
412 sctp_bind_addr_free(&asoc
->base
.bind_addr
);
414 /* Do we need to go through all of our timers and
415 * delete them? To be safe we will try to delete all, but we
416 * should be able to go through and make a guess based
419 for (i
= SCTP_EVENT_TIMEOUT_NONE
; i
< SCTP_NUM_TIMEOUT_TYPES
; ++i
) {
420 if (timer_pending(&asoc
->timers
[i
]) &&
421 del_timer(&asoc
->timers
[i
]))
422 sctp_association_put(asoc
);
425 /* Free peer's cached cookie. */
426 kfree(asoc
->peer
.cookie
);
427 kfree(asoc
->peer
.peer_random
);
428 kfree(asoc
->peer
.peer_chunks
);
429 kfree(asoc
->peer
.peer_hmacs
);
431 /* Release the transport structures. */
432 list_for_each_safe(pos
, temp
, &asoc
->peer
.transport_addr_list
) {
433 transport
= list_entry(pos
, struct sctp_transport
, transports
);
435 sctp_transport_free(transport
);
438 asoc
->peer
.transport_count
= 0;
440 /* Free any cached ASCONF_ACK chunk. */
441 sctp_assoc_free_asconf_acks(asoc
);
443 /* Free any cached ASCONF chunk. */
444 if (asoc
->addip_last_asconf
)
445 sctp_chunk_free(asoc
->addip_last_asconf
);
447 /* AUTH - Free the endpoint shared keys */
448 sctp_auth_destroy_keys(&asoc
->endpoint_shared_keys
);
450 /* AUTH - Free the association shared key */
451 sctp_auth_key_put(asoc
->asoc_shared_key
);
453 sctp_association_put(asoc
);
456 /* Cleanup and free up an association. */
457 static void sctp_association_destroy(struct sctp_association
*asoc
)
459 SCTP_ASSERT(asoc
->base
.dead
, "Assoc is not dead", return);
461 sctp_endpoint_put(asoc
->ep
);
462 sock_put(asoc
->base
.sk
);
464 if (asoc
->assoc_id
!= 0) {
465 spin_lock_bh(&sctp_assocs_id_lock
);
466 idr_remove(&sctp_assocs_id
, asoc
->assoc_id
);
467 spin_unlock_bh(&sctp_assocs_id_lock
);
470 WARN_ON(atomic_read(&asoc
->rmem_alloc
));
472 if (asoc
->base
.malloced
) {
474 SCTP_DBG_OBJCNT_DEC(assoc
);
478 /* Change the primary destination address for the peer. */
479 void sctp_assoc_set_primary(struct sctp_association
*asoc
,
480 struct sctp_transport
*transport
)
484 /* it's a changeover only if we already have a primary path
485 * that we are changing
487 if (asoc
->peer
.primary_path
!= NULL
&&
488 asoc
->peer
.primary_path
!= transport
)
491 asoc
->peer
.primary_path
= transport
;
493 /* Set a default msg_name for events. */
494 memcpy(&asoc
->peer
.primary_addr
, &transport
->ipaddr
,
495 sizeof(union sctp_addr
));
497 /* If the primary path is changing, assume that the
498 * user wants to use this new path.
500 if ((transport
->state
== SCTP_ACTIVE
) ||
501 (transport
->state
== SCTP_UNKNOWN
))
502 asoc
->peer
.active_path
= transport
;
505 * SFR-CACC algorithm:
506 * Upon the receipt of a request to change the primary
507 * destination address, on the data structure for the new
508 * primary destination, the sender MUST do the following:
510 * 1) If CHANGEOVER_ACTIVE is set, then there was a switch
511 * to this destination address earlier. The sender MUST set
512 * CYCLING_CHANGEOVER to indicate that this switch is a
513 * double switch to the same destination address.
515 if (transport
->cacc
.changeover_active
)
516 transport
->cacc
.cycling_changeover
= changeover
;
518 /* 2) The sender MUST set CHANGEOVER_ACTIVE to indicate that
519 * a changeover has occurred.
521 transport
->cacc
.changeover_active
= changeover
;
523 /* 3) The sender MUST store the next TSN to be sent in
524 * next_tsn_at_change.
526 transport
->cacc
.next_tsn_at_change
= asoc
->next_tsn
;
529 /* Remove a transport from an association. */
530 void sctp_assoc_rm_peer(struct sctp_association
*asoc
,
531 struct sctp_transport
*peer
)
533 struct list_head
*pos
;
534 struct sctp_transport
*transport
;
536 SCTP_DEBUG_PRINTK_IPADDR("sctp_assoc_rm_peer:association %p addr: ",
540 ntohs(peer
->ipaddr
.v4
.sin_port
));
542 /* If we are to remove the current retran_path, update it
543 * to the next peer before removing this peer from the list.
545 if (asoc
->peer
.retran_path
== peer
)
546 sctp_assoc_update_retran_path(asoc
);
548 /* Remove this peer from the list. */
549 list_del(&peer
->transports
);
551 /* Get the first transport of asoc. */
552 pos
= asoc
->peer
.transport_addr_list
.next
;
553 transport
= list_entry(pos
, struct sctp_transport
, transports
);
555 /* Update any entries that match the peer to be deleted. */
556 if (asoc
->peer
.primary_path
== peer
)
557 sctp_assoc_set_primary(asoc
, transport
);
558 if (asoc
->peer
.active_path
== peer
)
559 asoc
->peer
.active_path
= transport
;
560 if (asoc
->peer
.last_data_from
== peer
)
561 asoc
->peer
.last_data_from
= transport
;
563 /* If we remove the transport an INIT was last sent to, set it to
564 * NULL. Combined with the update of the retran path above, this
565 * will cause the next INIT to be sent to the next available
566 * transport, maintaining the cycle.
568 if (asoc
->init_last_sent_to
== peer
)
569 asoc
->init_last_sent_to
= NULL
;
571 /* If we remove the transport an SHUTDOWN was last sent to, set it
572 * to NULL. Combined with the update of the retran path above, this
573 * will cause the next SHUTDOWN to be sent to the next available
574 * transport, maintaining the cycle.
576 if (asoc
->shutdown_last_sent_to
== peer
)
577 asoc
->shutdown_last_sent_to
= NULL
;
579 /* If we remove the transport an ASCONF was last sent to, set it to
582 if (asoc
->addip_last_asconf
&&
583 asoc
->addip_last_asconf
->transport
== peer
)
584 asoc
->addip_last_asconf
->transport
= NULL
;
586 asoc
->peer
.transport_count
--;
588 sctp_transport_free(peer
);
591 /* Add a transport address to an association. */
592 struct sctp_transport
*sctp_assoc_add_peer(struct sctp_association
*asoc
,
593 const union sctp_addr
*addr
,
595 const int peer_state
)
597 struct sctp_transport
*peer
;
598 struct sctp_sock
*sp
;
601 sp
= sctp_sk(asoc
->base
.sk
);
603 /* AF_INET and AF_INET6 share common port field. */
604 port
= ntohs(addr
->v4
.sin_port
);
606 SCTP_DEBUG_PRINTK_IPADDR("sctp_assoc_add_peer:association %p addr: ",
607 " port: %d state:%d\n",
613 /* Set the port if it has not been set yet. */
614 if (0 == asoc
->peer
.port
)
615 asoc
->peer
.port
= port
;
617 /* Check to see if this is a duplicate. */
618 peer
= sctp_assoc_lookup_paddr(asoc
, addr
);
620 /* An UNKNOWN state is only set on transports added by
621 * user in sctp_connectx() call. Such transports should be
622 * considered CONFIRMED per RFC 4960, Section 5.4.
624 if (peer
->state
== SCTP_UNKNOWN
) {
625 peer
->state
= SCTP_ACTIVE
;
630 peer
= sctp_transport_new(addr
, gfp
);
634 sctp_transport_set_owner(peer
, asoc
);
636 /* Initialize the peer's heartbeat interval based on the
637 * association configured value.
639 peer
->hbinterval
= asoc
->hbinterval
;
641 /* Set the path max_retrans. */
642 peer
->pathmaxrxt
= asoc
->pathmaxrxt
;
644 /* Initialize the peer's SACK delay timeout based on the
645 * association configured value.
647 peer
->sackdelay
= asoc
->sackdelay
;
648 peer
->sackfreq
= asoc
->sackfreq
;
650 /* Enable/disable heartbeat, SACK delay, and path MTU discovery
651 * based on association setting.
653 peer
->param_flags
= asoc
->param_flags
;
655 /* Initialize the pmtu of the transport. */
656 if (peer
->param_flags
& SPP_PMTUD_ENABLE
)
657 sctp_transport_pmtu(peer
);
658 else if (asoc
->pathmtu
)
659 peer
->pathmtu
= asoc
->pathmtu
;
661 peer
->pathmtu
= SCTP_DEFAULT_MAXSEGMENT
;
663 /* If this is the first transport addr on this association,
664 * initialize the association PMTU to the peer's PMTU.
665 * If not and the current association PMTU is higher than the new
666 * peer's PMTU, reset the association PMTU to the new peer's PMTU.
669 asoc
->pathmtu
= min_t(int, peer
->pathmtu
, asoc
->pathmtu
);
671 asoc
->pathmtu
= peer
->pathmtu
;
673 SCTP_DEBUG_PRINTK("sctp_assoc_add_peer:association %p PMTU set to "
674 "%d\n", asoc
, asoc
->pathmtu
);
675 peer
->pmtu_pending
= 0;
677 asoc
->frag_point
= sctp_frag_point(sp
, asoc
->pathmtu
);
679 /* The asoc->peer.port might not be meaningful yet, but
680 * initialize the packet structure anyway.
682 sctp_packet_init(&peer
->packet
, peer
, asoc
->base
.bind_addr
.port
,
687 * o The initial cwnd before DATA transmission or after a sufficiently
688 * long idle period MUST be set to
689 * min(4*MTU, max(2*MTU, 4380 bytes))
691 * o The initial value of ssthresh MAY be arbitrarily high
692 * (for example, implementations MAY use the size of the
693 * receiver advertised window).
695 peer
->cwnd
= min(4*asoc
->pathmtu
, max_t(__u32
, 2*asoc
->pathmtu
, 4380));
697 /* At this point, we may not have the receiver's advertised window,
698 * so initialize ssthresh to the default value and it will be set
699 * later when we process the INIT.
701 peer
->ssthresh
= SCTP_DEFAULT_MAXWINDOW
;
703 peer
->partial_bytes_acked
= 0;
704 peer
->flight_size
= 0;
706 /* Set the transport's RTO.initial value */
707 peer
->rto
= asoc
->rto_initial
;
709 /* Set the peer's active state. */
710 peer
->state
= peer_state
;
712 /* Attach the remote transport to our asoc. */
713 list_add_tail(&peer
->transports
, &asoc
->peer
.transport_addr_list
);
714 asoc
->peer
.transport_count
++;
716 /* If we do not yet have a primary path, set one. */
717 if (!asoc
->peer
.primary_path
) {
718 sctp_assoc_set_primary(asoc
, peer
);
719 asoc
->peer
.retran_path
= peer
;
722 if (asoc
->peer
.active_path
== asoc
->peer
.retran_path
) {
723 asoc
->peer
.retran_path
= peer
;
729 /* Delete a transport address from an association. */
730 void sctp_assoc_del_peer(struct sctp_association
*asoc
,
731 const union sctp_addr
*addr
)
733 struct list_head
*pos
;
734 struct list_head
*temp
;
735 struct sctp_transport
*transport
;
737 list_for_each_safe(pos
, temp
, &asoc
->peer
.transport_addr_list
) {
738 transport
= list_entry(pos
, struct sctp_transport
, transports
);
739 if (sctp_cmp_addr_exact(addr
, &transport
->ipaddr
)) {
740 /* Do book keeping for removing the peer and free it. */
741 sctp_assoc_rm_peer(asoc
, transport
);
747 /* Lookup a transport by address. */
748 struct sctp_transport
*sctp_assoc_lookup_paddr(
749 const struct sctp_association
*asoc
,
750 const union sctp_addr
*address
)
752 struct sctp_transport
*t
;
754 /* Cycle through all transports searching for a peer address. */
756 list_for_each_entry(t
, &asoc
->peer
.transport_addr_list
,
758 if (sctp_cmp_addr_exact(address
, &t
->ipaddr
))
765 /* Remove all transports except a give one */
766 void sctp_assoc_del_nonprimary_peers(struct sctp_association
*asoc
,
767 struct sctp_transport
*primary
)
769 struct sctp_transport
*temp
;
770 struct sctp_transport
*t
;
772 list_for_each_entry_safe(t
, temp
, &asoc
->peer
.transport_addr_list
,
774 /* if the current transport is not the primary one, delete it */
776 sctp_assoc_rm_peer(asoc
, t
);
782 /* Engage in transport control operations.
783 * Mark the transport up or down and send a notification to the user.
784 * Select and update the new active and retran paths.
786 void sctp_assoc_control_transport(struct sctp_association
*asoc
,
787 struct sctp_transport
*transport
,
788 sctp_transport_cmd_t command
,
789 sctp_sn_error_t error
)
791 struct sctp_transport
*t
= NULL
;
792 struct sctp_transport
*first
;
793 struct sctp_transport
*second
;
794 struct sctp_ulpevent
*event
;
795 struct sockaddr_storage addr
;
798 /* Record the transition on the transport. */
800 case SCTP_TRANSPORT_UP
:
801 /* If we are moving from UNCONFIRMED state due
802 * to heartbeat success, report the SCTP_ADDR_CONFIRMED
803 * state to the user, otherwise report SCTP_ADDR_AVAILABLE.
805 if (SCTP_UNCONFIRMED
== transport
->state
&&
806 SCTP_HEARTBEAT_SUCCESS
== error
)
807 spc_state
= SCTP_ADDR_CONFIRMED
;
809 spc_state
= SCTP_ADDR_AVAILABLE
;
810 transport
->state
= SCTP_ACTIVE
;
813 case SCTP_TRANSPORT_DOWN
:
814 /* If the transport was never confirmed, do not transition it
815 * to inactive state. Also, release the cached route since
816 * there may be a better route next time.
818 if (transport
->state
!= SCTP_UNCONFIRMED
)
819 transport
->state
= SCTP_INACTIVE
;
821 dst_release(transport
->dst
);
822 transport
->dst
= NULL
;
825 spc_state
= SCTP_ADDR_UNREACHABLE
;
832 /* Generate and send a SCTP_PEER_ADDR_CHANGE notification to the
835 memset(&addr
, 0, sizeof(struct sockaddr_storage
));
836 memcpy(&addr
, &transport
->ipaddr
, transport
->af_specific
->sockaddr_len
);
837 event
= sctp_ulpevent_make_peer_addr_change(asoc
, &addr
,
838 0, spc_state
, error
, GFP_ATOMIC
);
840 sctp_ulpq_tail_event(&asoc
->ulpq
, event
);
842 /* Select new active and retran paths. */
844 /* Look for the two most recently used active transports.
846 * This code produces the wrong ordering whenever jiffies
847 * rolls over, but we still get usable transports, so we don't
850 first
= NULL
; second
= NULL
;
852 list_for_each_entry(t
, &asoc
->peer
.transport_addr_list
,
855 if ((t
->state
== SCTP_INACTIVE
) ||
856 (t
->state
== SCTP_UNCONFIRMED
))
858 if (!first
|| t
->last_time_heard
> first
->last_time_heard
) {
862 if (!second
|| t
->last_time_heard
> second
->last_time_heard
)
866 /* RFC 2960 6.4 Multi-Homed SCTP Endpoints
868 * By default, an endpoint should always transmit to the
869 * primary path, unless the SCTP user explicitly specifies the
870 * destination transport address (and possibly source
871 * transport address) to use.
873 * [If the primary is active but not most recent, bump the most
874 * recently used transport.]
876 if (((asoc
->peer
.primary_path
->state
== SCTP_ACTIVE
) ||
877 (asoc
->peer
.primary_path
->state
== SCTP_UNKNOWN
)) &&
878 first
!= asoc
->peer
.primary_path
) {
880 first
= asoc
->peer
.primary_path
;
883 /* If we failed to find a usable transport, just camp on the
884 * primary, even if it is inactive.
887 first
= asoc
->peer
.primary_path
;
888 second
= asoc
->peer
.primary_path
;
891 /* Set the active and retran transports. */
892 asoc
->peer
.active_path
= first
;
893 asoc
->peer
.retran_path
= second
;
896 /* Hold a reference to an association. */
897 void sctp_association_hold(struct sctp_association
*asoc
)
899 atomic_inc(&asoc
->base
.refcnt
);
902 /* Release a reference to an association and cleanup
903 * if there are no more references.
905 void sctp_association_put(struct sctp_association
*asoc
)
907 if (atomic_dec_and_test(&asoc
->base
.refcnt
))
908 sctp_association_destroy(asoc
);
911 /* Allocate the next TSN, Transmission Sequence Number, for the given
914 __u32
sctp_association_get_next_tsn(struct sctp_association
*asoc
)
916 /* From Section 1.6 Serial Number Arithmetic:
917 * Transmission Sequence Numbers wrap around when they reach
918 * 2**32 - 1. That is, the next TSN a DATA chunk MUST use
919 * after transmitting TSN = 2*32 - 1 is TSN = 0.
921 __u32 retval
= asoc
->next_tsn
;
928 /* Compare two addresses to see if they match. Wildcard addresses
929 * only match themselves.
931 int sctp_cmp_addr_exact(const union sctp_addr
*ss1
,
932 const union sctp_addr
*ss2
)
936 af
= sctp_get_af_specific(ss1
->sa
.sa_family
);
940 return af
->cmp_addr(ss1
, ss2
);
943 /* Return an ecne chunk to get prepended to a packet.
944 * Note: We are sly and return a shared, prealloced chunk. FIXME:
945 * No we don't, but we could/should.
947 struct sctp_chunk
*sctp_get_ecne_prepend(struct sctp_association
*asoc
)
949 struct sctp_chunk
*chunk
;
951 /* Send ECNE if needed.
952 * Not being able to allocate a chunk here is not deadly.
955 chunk
= sctp_make_ecne(asoc
, asoc
->last_ecne_tsn
);
963 * Find which transport this TSN was sent on.
965 struct sctp_transport
*sctp_assoc_lookup_tsn(struct sctp_association
*asoc
,
968 struct sctp_transport
*active
;
969 struct sctp_transport
*match
;
970 struct sctp_transport
*transport
;
971 struct sctp_chunk
*chunk
;
972 __be32 key
= htonl(tsn
);
977 * FIXME: In general, find a more efficient data structure for
982 * The general strategy is to search each transport's transmitted
983 * list. Return which transport this TSN lives on.
985 * Let's be hopeful and check the active_path first.
986 * Another optimization would be to know if there is only one
987 * outbound path and not have to look for the TSN at all.
991 active
= asoc
->peer
.active_path
;
993 list_for_each_entry(chunk
, &active
->transmitted
,
996 if (key
== chunk
->subh
.data_hdr
->tsn
) {
1002 /* If not found, go search all the other transports. */
1003 list_for_each_entry(transport
, &asoc
->peer
.transport_addr_list
,
1006 if (transport
== active
)
1008 list_for_each_entry(chunk
, &transport
->transmitted
,
1010 if (key
== chunk
->subh
.data_hdr
->tsn
) {
1020 /* Is this the association we are looking for? */
1021 struct sctp_transport
*sctp_assoc_is_match(struct sctp_association
*asoc
,
1022 const union sctp_addr
*laddr
,
1023 const union sctp_addr
*paddr
)
1025 struct sctp_transport
*transport
;
1027 if ((htons(asoc
->base
.bind_addr
.port
) == laddr
->v4
.sin_port
) &&
1028 (htons(asoc
->peer
.port
) == paddr
->v4
.sin_port
)) {
1029 transport
= sctp_assoc_lookup_paddr(asoc
, paddr
);
1033 if (sctp_bind_addr_match(&asoc
->base
.bind_addr
, laddr
,
1034 sctp_sk(asoc
->base
.sk
)))
1043 /* Do delayed input processing. This is scheduled by sctp_rcv(). */
1044 static void sctp_assoc_bh_rcv(struct work_struct
*work
)
1046 struct sctp_association
*asoc
=
1047 container_of(work
, struct sctp_association
,
1048 base
.inqueue
.immediate
);
1049 struct sctp_endpoint
*ep
;
1050 struct sctp_chunk
*chunk
;
1052 struct sctp_inq
*inqueue
;
1054 sctp_subtype_t subtype
;
1057 /* The association should be held so we should be safe. */
1061 inqueue
= &asoc
->base
.inqueue
;
1062 sctp_association_hold(asoc
);
1063 while (NULL
!= (chunk
= sctp_inq_pop(inqueue
))) {
1064 state
= asoc
->state
;
1065 subtype
= SCTP_ST_CHUNK(chunk
->chunk_hdr
->type
);
1067 /* SCTP-AUTH, Section 6.3:
1068 * The receiver has a list of chunk types which it expects
1069 * to be received only after an AUTH-chunk. This list has
1070 * been sent to the peer during the association setup. It
1071 * MUST silently discard these chunks if they are not placed
1072 * after an AUTH chunk in the packet.
1074 if (sctp_auth_recv_cid(subtype
.chunk
, asoc
) && !chunk
->auth
)
1077 /* Remember where the last DATA chunk came from so we
1078 * know where to send the SACK.
1080 if (sctp_chunk_is_data(chunk
))
1081 asoc
->peer
.last_data_from
= chunk
->transport
;
1083 SCTP_INC_STATS(SCTP_MIB_INCTRLCHUNKS
);
1085 if (chunk
->transport
)
1086 chunk
->transport
->last_time_heard
= jiffies
;
1088 /* Run through the state machine. */
1089 error
= sctp_do_sm(SCTP_EVENT_T_CHUNK
, subtype
,
1090 state
, ep
, asoc
, chunk
, GFP_ATOMIC
);
1092 /* Check to see if the association is freed in response to
1093 * the incoming chunk. If so, get out of the while loop.
1095 if (asoc
->base
.dead
)
1098 /* If there is an error on chunk, discard this packet. */
1100 chunk
->pdiscard
= 1;
1102 sctp_association_put(asoc
);
1105 /* This routine moves an association from its old sk to a new sk. */
1106 void sctp_assoc_migrate(struct sctp_association
*assoc
, struct sock
*newsk
)
1108 struct sctp_sock
*newsp
= sctp_sk(newsk
);
1109 struct sock
*oldsk
= assoc
->base
.sk
;
1111 /* Delete the association from the old endpoint's list of
1114 list_del_init(&assoc
->asocs
);
1116 /* Decrement the backlog value for a TCP-style socket. */
1117 if (sctp_style(oldsk
, TCP
))
1118 oldsk
->sk_ack_backlog
--;
1120 /* Release references to the old endpoint and the sock. */
1121 sctp_endpoint_put(assoc
->ep
);
1122 sock_put(assoc
->base
.sk
);
1124 /* Get a reference to the new endpoint. */
1125 assoc
->ep
= newsp
->ep
;
1126 sctp_endpoint_hold(assoc
->ep
);
1128 /* Get a reference to the new sock. */
1129 assoc
->base
.sk
= newsk
;
1130 sock_hold(assoc
->base
.sk
);
1132 /* Add the association to the new endpoint's list of associations. */
1133 sctp_endpoint_add_asoc(newsp
->ep
, assoc
);
1136 /* Update an association (possibly from unexpected COOKIE-ECHO processing). */
1137 void sctp_assoc_update(struct sctp_association
*asoc
,
1138 struct sctp_association
*new)
1140 struct sctp_transport
*trans
;
1141 struct list_head
*pos
, *temp
;
1143 /* Copy in new parameters of peer. */
1145 asoc
->peer
.rwnd
= new->peer
.rwnd
;
1146 asoc
->peer
.sack_needed
= new->peer
.sack_needed
;
1147 asoc
->peer
.i
= new->peer
.i
;
1148 sctp_tsnmap_init(&asoc
->peer
.tsn_map
, SCTP_TSN_MAP_INITIAL
,
1149 asoc
->peer
.i
.initial_tsn
, GFP_ATOMIC
);
1151 /* Remove any peer addresses not present in the new association. */
1152 list_for_each_safe(pos
, temp
, &asoc
->peer
.transport_addr_list
) {
1153 trans
= list_entry(pos
, struct sctp_transport
, transports
);
1154 if (!sctp_assoc_lookup_paddr(new, &trans
->ipaddr
))
1155 sctp_assoc_del_peer(asoc
, &trans
->ipaddr
);
1157 if (asoc
->state
>= SCTP_STATE_ESTABLISHED
)
1158 sctp_transport_reset(trans
);
1161 /* If the case is A (association restart), use
1162 * initial_tsn as next_tsn. If the case is B, use
1163 * current next_tsn in case data sent to peer
1164 * has been discarded and needs retransmission.
1166 if (asoc
->state
>= SCTP_STATE_ESTABLISHED
) {
1167 asoc
->next_tsn
= new->next_tsn
;
1168 asoc
->ctsn_ack_point
= new->ctsn_ack_point
;
1169 asoc
->adv_peer_ack_point
= new->adv_peer_ack_point
;
1171 /* Reinitialize SSN for both local streams
1172 * and peer's streams.
1174 sctp_ssnmap_clear(asoc
->ssnmap
);
1176 /* Flush the ULP reassembly and ordered queue.
1177 * Any data there will now be stale and will
1180 sctp_ulpq_flush(&asoc
->ulpq
);
1182 /* reset the overall association error count so
1183 * that the restarted association doesn't get torn
1184 * down on the next retransmission timer.
1186 asoc
->overall_error_count
= 0;
1189 /* Add any peer addresses from the new association. */
1190 list_for_each_entry(trans
, &new->peer
.transport_addr_list
,
1192 if (!sctp_assoc_lookup_paddr(asoc
, &trans
->ipaddr
))
1193 sctp_assoc_add_peer(asoc
, &trans
->ipaddr
,
1194 GFP_ATOMIC
, trans
->state
);
1197 asoc
->ctsn_ack_point
= asoc
->next_tsn
- 1;
1198 asoc
->adv_peer_ack_point
= asoc
->ctsn_ack_point
;
1199 if (!asoc
->ssnmap
) {
1200 /* Move the ssnmap. */
1201 asoc
->ssnmap
= new->ssnmap
;
1205 if (!asoc
->assoc_id
) {
1206 /* get a new association id since we don't have one
1209 sctp_assoc_set_id(asoc
, GFP_ATOMIC
);
1213 /* SCTP-AUTH: Save the peer parameters from the new assocaitions
1214 * and also move the association shared keys over
1216 kfree(asoc
->peer
.peer_random
);
1217 asoc
->peer
.peer_random
= new->peer
.peer_random
;
1218 new->peer
.peer_random
= NULL
;
1220 kfree(asoc
->peer
.peer_chunks
);
1221 asoc
->peer
.peer_chunks
= new->peer
.peer_chunks
;
1222 new->peer
.peer_chunks
= NULL
;
1224 kfree(asoc
->peer
.peer_hmacs
);
1225 asoc
->peer
.peer_hmacs
= new->peer
.peer_hmacs
;
1226 new->peer
.peer_hmacs
= NULL
;
1228 sctp_auth_key_put(asoc
->asoc_shared_key
);
1229 sctp_auth_asoc_init_active_key(asoc
, GFP_ATOMIC
);
1232 /* Update the retran path for sending a retransmitted packet.
1233 * Round-robin through the active transports, else round-robin
1234 * through the inactive transports as this is the next best thing
1237 void sctp_assoc_update_retran_path(struct sctp_association
*asoc
)
1239 struct sctp_transport
*t
, *next
;
1240 struct list_head
*head
= &asoc
->peer
.transport_addr_list
;
1241 struct list_head
*pos
;
1243 if (asoc
->peer
.transport_count
== 1)
1246 /* Find the next transport in a round-robin fashion. */
1247 t
= asoc
->peer
.retran_path
;
1248 pos
= &t
->transports
;
1252 /* Skip the head. */
1253 if (pos
->next
== head
)
1258 t
= list_entry(pos
, struct sctp_transport
, transports
);
1260 /* We have exhausted the list, but didn't find any
1261 * other active transports. If so, use the next
1264 if (t
== asoc
->peer
.retran_path
) {
1269 /* Try to find an active transport. */
1271 if ((t
->state
== SCTP_ACTIVE
) ||
1272 (t
->state
== SCTP_UNKNOWN
)) {
1275 /* Keep track of the next transport in case
1276 * we don't find any active transport.
1283 asoc
->peer
.retran_path
= t
;
1285 SCTP_DEBUG_PRINTK_IPADDR("sctp_assoc_update_retran_path:association"
1290 ntohs(t
->ipaddr
.v4
.sin_port
));
1293 /* Choose the transport for sending retransmit packet. */
1294 struct sctp_transport
*sctp_assoc_choose_alter_transport(
1295 struct sctp_association
*asoc
, struct sctp_transport
*last_sent_to
)
1297 /* If this is the first time packet is sent, use the active path,
1298 * else use the retran path. If the last packet was sent over the
1299 * retran path, update the retran path and use it.
1302 return asoc
->peer
.active_path
;
1304 if (last_sent_to
== asoc
->peer
.retran_path
)
1305 sctp_assoc_update_retran_path(asoc
);
1306 return asoc
->peer
.retran_path
;
1310 /* Update the association's pmtu and frag_point by going through all the
1311 * transports. This routine is called when a transport's PMTU has changed.
1313 void sctp_assoc_sync_pmtu(struct sctp_association
*asoc
)
1315 struct sctp_transport
*t
;
1321 /* Get the lowest pmtu of all the transports. */
1322 list_for_each_entry(t
, &asoc
->peer
.transport_addr_list
,
1324 if (t
->pmtu_pending
&& t
->dst
) {
1325 sctp_transport_update_pmtu(t
, dst_mtu(t
->dst
));
1326 t
->pmtu_pending
= 0;
1328 if (!pmtu
|| (t
->pathmtu
< pmtu
))
1333 struct sctp_sock
*sp
= sctp_sk(asoc
->base
.sk
);
1334 asoc
->pathmtu
= pmtu
;
1335 asoc
->frag_point
= sctp_frag_point(sp
, 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
);