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1/*
2 BlueZ - Bluetooth protocol stack for Linux
3 Copyright (C) 2000-2001 Qualcomm Incorporated
4 Copyright (C) 2009-2010 Gustavo F. Padovan <gustavo@padovan.org>
5 Copyright (C) 2010 Google Inc.
6 Copyright (C) 2011 ProFUSION Embedded Systems
7 Copyright (c) 2012 Code Aurora Forum. All rights reserved.
8
9 Written 2000,2001 by Maxim Krasnyansky <maxk@qualcomm.com>
10
11 This program is free software; you can redistribute it and/or modify
12 it under the terms of the GNU General Public License version 2 as
13 published by the Free Software Foundation;
14
15 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
16 OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS.
18 IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) AND AUTHOR(S) BE LIABLE FOR ANY
19 CLAIM, OR ANY SPECIAL INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES
20 WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
21 ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
22 OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
23
24 ALL LIABILITY, INCLUDING LIABILITY FOR INFRINGEMENT OF ANY PATENTS,
25 COPYRIGHTS, TRADEMARKS OR OTHER RIGHTS, RELATING TO USE OF THIS
26 SOFTWARE IS DISCLAIMED.
27*/
28
29/* Bluetooth L2CAP core. */
30
31#include <linux/module.h>
32
33#include <linux/debugfs.h>
34#include <linux/crc16.h>
35#include <linux/filter.h>
36
37#include <net/bluetooth/bluetooth.h>
38#include <net/bluetooth/hci_core.h>
39#include <net/bluetooth/l2cap.h>
40
41#include "smp.h"
42#include "a2mp.h"
43#include "amp.h"
44
45#define LE_FLOWCTL_MAX_CREDITS 65535
46
47bool disable_ertm;
48bool enable_ecred = IS_ENABLED(CONFIG_BT_LE_L2CAP_ECRED);
49
50static u32 l2cap_feat_mask = L2CAP_FEAT_FIXED_CHAN | L2CAP_FEAT_UCD;
51
52static LIST_HEAD(chan_list);
53static DEFINE_RWLOCK(chan_list_lock);
54
55static struct sk_buff *l2cap_build_cmd(struct l2cap_conn *conn,
56 u8 code, u8 ident, u16 dlen, void *data);
57static void l2cap_send_cmd(struct l2cap_conn *conn, u8 ident, u8 code, u16 len,
58 void *data);
59static int l2cap_build_conf_req(struct l2cap_chan *chan, void *data, size_t data_size);
60static void l2cap_send_disconn_req(struct l2cap_chan *chan, int err);
61
62static void l2cap_tx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
63 struct sk_buff_head *skbs, u8 event);
64static void l2cap_retrans_timeout(struct work_struct *work);
65static void l2cap_monitor_timeout(struct work_struct *work);
66static void l2cap_ack_timeout(struct work_struct *work);
67
68static inline u8 bdaddr_type(u8 link_type, u8 bdaddr_type)
69{
70 if (link_type == LE_LINK) {
71 if (bdaddr_type == ADDR_LE_DEV_PUBLIC)
72 return BDADDR_LE_PUBLIC;
73 else
74 return BDADDR_LE_RANDOM;
75 }
76
77 return BDADDR_BREDR;
78}
79
80static inline u8 bdaddr_src_type(struct hci_conn *hcon)
81{
82 return bdaddr_type(hcon->type, hcon->src_type);
83}
84
85static inline u8 bdaddr_dst_type(struct hci_conn *hcon)
86{
87 return bdaddr_type(hcon->type, hcon->dst_type);
88}
89
90/* ---- L2CAP channels ---- */
91
92static struct l2cap_chan *__l2cap_get_chan_by_dcid(struct l2cap_conn *conn,
93 u16 cid)
94{
95 struct l2cap_chan *c;
96
97 list_for_each_entry(c, &conn->chan_l, list) {
98 if (c->dcid == cid)
99 return c;
100 }
101 return NULL;
102}
103
104static struct l2cap_chan *__l2cap_get_chan_by_scid(struct l2cap_conn *conn,
105 u16 cid)
106{
107 struct l2cap_chan *c;
108
109 list_for_each_entry(c, &conn->chan_l, list) {
110 if (c->scid == cid)
111 return c;
112 }
113 return NULL;
114}
115
116/* Find channel with given SCID.
117 * Returns a reference locked channel.
118 */
119static struct l2cap_chan *l2cap_get_chan_by_scid(struct l2cap_conn *conn,
120 u16 cid)
121{
122 struct l2cap_chan *c;
123
124 mutex_lock(&conn->chan_lock);
125 c = __l2cap_get_chan_by_scid(conn, cid);
126 if (c) {
127 /* Only lock if chan reference is not 0 */
128 c = l2cap_chan_hold_unless_zero(c);
129 if (c)
130 l2cap_chan_lock(c);
131 }
132 mutex_unlock(&conn->chan_lock);
133
134 return c;
135}
136
137/* Find channel with given DCID.
138 * Returns a reference locked channel.
139 */
140static struct l2cap_chan *l2cap_get_chan_by_dcid(struct l2cap_conn *conn,
141 u16 cid)
142{
143 struct l2cap_chan *c;
144
145 mutex_lock(&conn->chan_lock);
146 c = __l2cap_get_chan_by_dcid(conn, cid);
147 if (c) {
148 /* Only lock if chan reference is not 0 */
149 c = l2cap_chan_hold_unless_zero(c);
150 if (c)
151 l2cap_chan_lock(c);
152 }
153 mutex_unlock(&conn->chan_lock);
154
155 return c;
156}
157
158static struct l2cap_chan *__l2cap_get_chan_by_ident(struct l2cap_conn *conn,
159 u8 ident)
160{
161 struct l2cap_chan *c;
162
163 list_for_each_entry(c, &conn->chan_l, list) {
164 if (c->ident == ident)
165 return c;
166 }
167 return NULL;
168}
169
170static struct l2cap_chan *l2cap_get_chan_by_ident(struct l2cap_conn *conn,
171 u8 ident)
172{
173 struct l2cap_chan *c;
174
175 mutex_lock(&conn->chan_lock);
176 c = __l2cap_get_chan_by_ident(conn, ident);
177 if (c) {
178 /* Only lock if chan reference is not 0 */
179 c = l2cap_chan_hold_unless_zero(c);
180 if (c)
181 l2cap_chan_lock(c);
182 }
183 mutex_unlock(&conn->chan_lock);
184
185 return c;
186}
187
188static struct l2cap_chan *__l2cap_global_chan_by_addr(__le16 psm, bdaddr_t *src,
189 u8 src_type)
190{
191 struct l2cap_chan *c;
192
193 list_for_each_entry(c, &chan_list, global_l) {
194 if (src_type == BDADDR_BREDR && c->src_type != BDADDR_BREDR)
195 continue;
196
197 if (src_type != BDADDR_BREDR && c->src_type == BDADDR_BREDR)
198 continue;
199
200 if (c->sport == psm && !bacmp(&c->src, src))
201 return c;
202 }
203 return NULL;
204}
205
206int l2cap_add_psm(struct l2cap_chan *chan, bdaddr_t *src, __le16 psm)
207{
208 int err;
209
210 write_lock(&chan_list_lock);
211
212 if (psm && __l2cap_global_chan_by_addr(psm, src, chan->src_type)) {
213 err = -EADDRINUSE;
214 goto done;
215 }
216
217 if (psm) {
218 chan->psm = psm;
219 chan->sport = psm;
220 err = 0;
221 } else {
222 u16 p, start, end, incr;
223
224 if (chan->src_type == BDADDR_BREDR) {
225 start = L2CAP_PSM_DYN_START;
226 end = L2CAP_PSM_AUTO_END;
227 incr = 2;
228 } else {
229 start = L2CAP_PSM_LE_DYN_START;
230 end = L2CAP_PSM_LE_DYN_END;
231 incr = 1;
232 }
233
234 err = -EINVAL;
235 for (p = start; p <= end; p += incr)
236 if (!__l2cap_global_chan_by_addr(cpu_to_le16(p), src,
237 chan->src_type)) {
238 chan->psm = cpu_to_le16(p);
239 chan->sport = cpu_to_le16(p);
240 err = 0;
241 break;
242 }
243 }
244
245done:
246 write_unlock(&chan_list_lock);
247 return err;
248}
249EXPORT_SYMBOL_GPL(l2cap_add_psm);
250
251int l2cap_add_scid(struct l2cap_chan *chan, __u16 scid)
252{
253 write_lock(&chan_list_lock);
254
255 /* Override the defaults (which are for conn-oriented) */
256 chan->omtu = L2CAP_DEFAULT_MTU;
257 chan->chan_type = L2CAP_CHAN_FIXED;
258
259 chan->scid = scid;
260
261 write_unlock(&chan_list_lock);
262
263 return 0;
264}
265
266static u16 l2cap_alloc_cid(struct l2cap_conn *conn)
267{
268 u16 cid, dyn_end;
269
270 if (conn->hcon->type == LE_LINK)
271 dyn_end = L2CAP_CID_LE_DYN_END;
272 else
273 dyn_end = L2CAP_CID_DYN_END;
274
275 for (cid = L2CAP_CID_DYN_START; cid <= dyn_end; cid++) {
276 if (!__l2cap_get_chan_by_scid(conn, cid))
277 return cid;
278 }
279
280 return 0;
281}
282
283static void l2cap_state_change(struct l2cap_chan *chan, int state)
284{
285 BT_DBG("chan %p %s -> %s", chan, state_to_string(chan->state),
286 state_to_string(state));
287
288 chan->state = state;
289 chan->ops->state_change(chan, state, 0);
290}
291
292static inline void l2cap_state_change_and_error(struct l2cap_chan *chan,
293 int state, int err)
294{
295 chan->state = state;
296 chan->ops->state_change(chan, chan->state, err);
297}
298
299static inline void l2cap_chan_set_err(struct l2cap_chan *chan, int err)
300{
301 chan->ops->state_change(chan, chan->state, err);
302}
303
304static void __set_retrans_timer(struct l2cap_chan *chan)
305{
306 if (!delayed_work_pending(&chan->monitor_timer) &&
307 chan->retrans_timeout) {
308 l2cap_set_timer(chan, &chan->retrans_timer,
309 msecs_to_jiffies(chan->retrans_timeout));
310 }
311}
312
313static void __set_monitor_timer(struct l2cap_chan *chan)
314{
315 __clear_retrans_timer(chan);
316 if (chan->monitor_timeout) {
317 l2cap_set_timer(chan, &chan->monitor_timer,
318 msecs_to_jiffies(chan->monitor_timeout));
319 }
320}
321
322static struct sk_buff *l2cap_ertm_seq_in_queue(struct sk_buff_head *head,
323 u16 seq)
324{
325 struct sk_buff *skb;
326
327 skb_queue_walk(head, skb) {
328 if (bt_cb(skb)->l2cap.txseq == seq)
329 return skb;
330 }
331
332 return NULL;
333}
334
335/* ---- L2CAP sequence number lists ---- */
336
337/* For ERTM, ordered lists of sequence numbers must be tracked for
338 * SREJ requests that are received and for frames that are to be
339 * retransmitted. These seq_list functions implement a singly-linked
340 * list in an array, where membership in the list can also be checked
341 * in constant time. Items can also be added to the tail of the list
342 * and removed from the head in constant time, without further memory
343 * allocs or frees.
344 */
345
346static int l2cap_seq_list_init(struct l2cap_seq_list *seq_list, u16 size)
347{
348 size_t alloc_size, i;
349
350 /* Allocated size is a power of 2 to map sequence numbers
351 * (which may be up to 14 bits) in to a smaller array that is
352 * sized for the negotiated ERTM transmit windows.
353 */
354 alloc_size = roundup_pow_of_two(size);
355
356 seq_list->list = kmalloc_array(alloc_size, sizeof(u16), GFP_KERNEL);
357 if (!seq_list->list)
358 return -ENOMEM;
359
360 seq_list->mask = alloc_size - 1;
361 seq_list->head = L2CAP_SEQ_LIST_CLEAR;
362 seq_list->tail = L2CAP_SEQ_LIST_CLEAR;
363 for (i = 0; i < alloc_size; i++)
364 seq_list->list[i] = L2CAP_SEQ_LIST_CLEAR;
365
366 return 0;
367}
368
369static inline void l2cap_seq_list_free(struct l2cap_seq_list *seq_list)
370{
371 kfree(seq_list->list);
372}
373
374static inline bool l2cap_seq_list_contains(struct l2cap_seq_list *seq_list,
375 u16 seq)
376{
377 /* Constant-time check for list membership */
378 return seq_list->list[seq & seq_list->mask] != L2CAP_SEQ_LIST_CLEAR;
379}
380
381static inline u16 l2cap_seq_list_pop(struct l2cap_seq_list *seq_list)
382{
383 u16 seq = seq_list->head;
384 u16 mask = seq_list->mask;
385
386 seq_list->head = seq_list->list[seq & mask];
387 seq_list->list[seq & mask] = L2CAP_SEQ_LIST_CLEAR;
388
389 if (seq_list->head == L2CAP_SEQ_LIST_TAIL) {
390 seq_list->head = L2CAP_SEQ_LIST_CLEAR;
391 seq_list->tail = L2CAP_SEQ_LIST_CLEAR;
392 }
393
394 return seq;
395}
396
397static void l2cap_seq_list_clear(struct l2cap_seq_list *seq_list)
398{
399 u16 i;
400
401 if (seq_list->head == L2CAP_SEQ_LIST_CLEAR)
402 return;
403
404 for (i = 0; i <= seq_list->mask; i++)
405 seq_list->list[i] = L2CAP_SEQ_LIST_CLEAR;
406
407 seq_list->head = L2CAP_SEQ_LIST_CLEAR;
408 seq_list->tail = L2CAP_SEQ_LIST_CLEAR;
409}
410
411static void l2cap_seq_list_append(struct l2cap_seq_list *seq_list, u16 seq)
412{
413 u16 mask = seq_list->mask;
414
415 /* All appends happen in constant time */
416
417 if (seq_list->list[seq & mask] != L2CAP_SEQ_LIST_CLEAR)
418 return;
419
420 if (seq_list->tail == L2CAP_SEQ_LIST_CLEAR)
421 seq_list->head = seq;
422 else
423 seq_list->list[seq_list->tail & mask] = seq;
424
425 seq_list->tail = seq;
426 seq_list->list[seq & mask] = L2CAP_SEQ_LIST_TAIL;
427}
428
429static void l2cap_chan_timeout(struct work_struct *work)
430{
431 struct l2cap_chan *chan = container_of(work, struct l2cap_chan,
432 chan_timer.work);
433 struct l2cap_conn *conn = chan->conn;
434 int reason;
435
436 BT_DBG("chan %p state %s", chan, state_to_string(chan->state));
437
438 mutex_lock(&conn->chan_lock);
439 /* __set_chan_timer() calls l2cap_chan_hold(chan) while scheduling
440 * this work. No need to call l2cap_chan_hold(chan) here again.
441 */
442 l2cap_chan_lock(chan);
443
444 if (chan->state == BT_CONNECTED || chan->state == BT_CONFIG)
445 reason = ECONNREFUSED;
446 else if (chan->state == BT_CONNECT &&
447 chan->sec_level != BT_SECURITY_SDP)
448 reason = ECONNREFUSED;
449 else
450 reason = ETIMEDOUT;
451
452 l2cap_chan_close(chan, reason);
453
454 chan->ops->close(chan);
455
456 l2cap_chan_unlock(chan);
457 l2cap_chan_put(chan);
458
459 mutex_unlock(&conn->chan_lock);
460}
461
462struct l2cap_chan *l2cap_chan_create(void)
463{
464 struct l2cap_chan *chan;
465
466 chan = kzalloc(sizeof(*chan), GFP_ATOMIC);
467 if (!chan)
468 return NULL;
469
470 skb_queue_head_init(&chan->tx_q);
471 skb_queue_head_init(&chan->srej_q);
472 mutex_init(&chan->lock);
473
474 /* Set default lock nesting level */
475 atomic_set(&chan->nesting, L2CAP_NESTING_NORMAL);
476
477 write_lock(&chan_list_lock);
478 list_add(&chan->global_l, &chan_list);
479 write_unlock(&chan_list_lock);
480
481 INIT_DELAYED_WORK(&chan->chan_timer, l2cap_chan_timeout);
482 INIT_DELAYED_WORK(&chan->retrans_timer, l2cap_retrans_timeout);
483 INIT_DELAYED_WORK(&chan->monitor_timer, l2cap_monitor_timeout);
484 INIT_DELAYED_WORK(&chan->ack_timer, l2cap_ack_timeout);
485
486 chan->state = BT_OPEN;
487
488 kref_init(&chan->kref);
489
490 /* This flag is cleared in l2cap_chan_ready() */
491 set_bit(CONF_NOT_COMPLETE, &chan->conf_state);
492
493 BT_DBG("chan %p", chan);
494
495 return chan;
496}
497EXPORT_SYMBOL_GPL(l2cap_chan_create);
498
499static void l2cap_chan_destroy(struct kref *kref)
500{
501 struct l2cap_chan *chan = container_of(kref, struct l2cap_chan, kref);
502
503 BT_DBG("chan %p", chan);
504
505 write_lock(&chan_list_lock);
506 list_del(&chan->global_l);
507 write_unlock(&chan_list_lock);
508
509 kfree(chan);
510}
511
512void l2cap_chan_hold(struct l2cap_chan *c)
513{
514 BT_DBG("chan %p orig refcnt %u", c, kref_read(&c->kref));
515
516 kref_get(&c->kref);
517}
518
519struct l2cap_chan *l2cap_chan_hold_unless_zero(struct l2cap_chan *c)
520{
521 BT_DBG("chan %p orig refcnt %u", c, kref_read(&c->kref));
522
523 if (!kref_get_unless_zero(&c->kref))
524 return NULL;
525
526 return c;
527}
528
529void l2cap_chan_put(struct l2cap_chan *c)
530{
531 BT_DBG("chan %p orig refcnt %u", c, kref_read(&c->kref));
532
533 kref_put(&c->kref, l2cap_chan_destroy);
534}
535EXPORT_SYMBOL_GPL(l2cap_chan_put);
536
537void l2cap_chan_set_defaults(struct l2cap_chan *chan)
538{
539 chan->fcs = L2CAP_FCS_CRC16;
540 chan->max_tx = L2CAP_DEFAULT_MAX_TX;
541 chan->tx_win = L2CAP_DEFAULT_TX_WINDOW;
542 chan->tx_win_max = L2CAP_DEFAULT_TX_WINDOW;
543 chan->remote_max_tx = chan->max_tx;
544 chan->remote_tx_win = chan->tx_win;
545 chan->ack_win = L2CAP_DEFAULT_TX_WINDOW;
546 chan->sec_level = BT_SECURITY_LOW;
547 chan->flush_to = L2CAP_DEFAULT_FLUSH_TO;
548 chan->retrans_timeout = L2CAP_DEFAULT_RETRANS_TO;
549 chan->monitor_timeout = L2CAP_DEFAULT_MONITOR_TO;
550
551 chan->conf_state = 0;
552 set_bit(CONF_NOT_COMPLETE, &chan->conf_state);
553
554 set_bit(FLAG_FORCE_ACTIVE, &chan->flags);
555}
556EXPORT_SYMBOL_GPL(l2cap_chan_set_defaults);
557
558static void l2cap_le_flowctl_init(struct l2cap_chan *chan, u16 tx_credits)
559{
560 chan->sdu = NULL;
561 chan->sdu_last_frag = NULL;
562 chan->sdu_len = 0;
563 chan->tx_credits = tx_credits;
564 /* Derive MPS from connection MTU to stop HCI fragmentation */
565 chan->mps = min_t(u16, chan->imtu, chan->conn->mtu - L2CAP_HDR_SIZE);
566 /* Give enough credits for a full packet */
567 chan->rx_credits = (chan->imtu / chan->mps) + 1;
568
569 skb_queue_head_init(&chan->tx_q);
570}
571
572static void l2cap_ecred_init(struct l2cap_chan *chan, u16 tx_credits)
573{
574 l2cap_le_flowctl_init(chan, tx_credits);
575
576 /* L2CAP implementations shall support a minimum MPS of 64 octets */
577 if (chan->mps < L2CAP_ECRED_MIN_MPS) {
578 chan->mps = L2CAP_ECRED_MIN_MPS;
579 chan->rx_credits = (chan->imtu / chan->mps) + 1;
580 }
581}
582
583void __l2cap_chan_add(struct l2cap_conn *conn, struct l2cap_chan *chan)
584{
585 BT_DBG("conn %p, psm 0x%2.2x, dcid 0x%4.4x", conn,
586 __le16_to_cpu(chan->psm), chan->dcid);
587
588 conn->disc_reason = HCI_ERROR_REMOTE_USER_TERM;
589
590 chan->conn = conn;
591
592 switch (chan->chan_type) {
593 case L2CAP_CHAN_CONN_ORIENTED:
594 /* Alloc CID for connection-oriented socket */
595 chan->scid = l2cap_alloc_cid(conn);
596 if (conn->hcon->type == ACL_LINK)
597 chan->omtu = L2CAP_DEFAULT_MTU;
598 break;
599
600 case L2CAP_CHAN_CONN_LESS:
601 /* Connectionless socket */
602 chan->scid = L2CAP_CID_CONN_LESS;
603 chan->dcid = L2CAP_CID_CONN_LESS;
604 chan->omtu = L2CAP_DEFAULT_MTU;
605 break;
606
607 case L2CAP_CHAN_FIXED:
608 /* Caller will set CID and CID specific MTU values */
609 break;
610
611 default:
612 /* Raw socket can send/recv signalling messages only */
613 chan->scid = L2CAP_CID_SIGNALING;
614 chan->dcid = L2CAP_CID_SIGNALING;
615 chan->omtu = L2CAP_DEFAULT_MTU;
616 }
617
618 chan->local_id = L2CAP_BESTEFFORT_ID;
619 chan->local_stype = L2CAP_SERV_BESTEFFORT;
620 chan->local_msdu = L2CAP_DEFAULT_MAX_SDU_SIZE;
621 chan->local_sdu_itime = L2CAP_DEFAULT_SDU_ITIME;
622 chan->local_acc_lat = L2CAP_DEFAULT_ACC_LAT;
623 chan->local_flush_to = L2CAP_EFS_DEFAULT_FLUSH_TO;
624
625 l2cap_chan_hold(chan);
626
627 /* Only keep a reference for fixed channels if they requested it */
628 if (chan->chan_type != L2CAP_CHAN_FIXED ||
629 test_bit(FLAG_HOLD_HCI_CONN, &chan->flags))
630 hci_conn_hold(conn->hcon);
631
632 list_add(&chan->list, &conn->chan_l);
633}
634
635void l2cap_chan_add(struct l2cap_conn *conn, struct l2cap_chan *chan)
636{
637 mutex_lock(&conn->chan_lock);
638 __l2cap_chan_add(conn, chan);
639 mutex_unlock(&conn->chan_lock);
640}
641
642void l2cap_chan_del(struct l2cap_chan *chan, int err)
643{
644 struct l2cap_conn *conn = chan->conn;
645
646 __clear_chan_timer(chan);
647
648 BT_DBG("chan %p, conn %p, err %d, state %s", chan, conn, err,
649 state_to_string(chan->state));
650
651 chan->ops->teardown(chan, err);
652
653 if (conn) {
654 struct amp_mgr *mgr = conn->hcon->amp_mgr;
655 /* Delete from channel list */
656 list_del(&chan->list);
657
658 l2cap_chan_put(chan);
659
660 chan->conn = NULL;
661
662 /* Reference was only held for non-fixed channels or
663 * fixed channels that explicitly requested it using the
664 * FLAG_HOLD_HCI_CONN flag.
665 */
666 if (chan->chan_type != L2CAP_CHAN_FIXED ||
667 test_bit(FLAG_HOLD_HCI_CONN, &chan->flags))
668 hci_conn_drop(conn->hcon);
669
670 if (mgr && mgr->bredr_chan == chan)
671 mgr->bredr_chan = NULL;
672 }
673
674 if (chan->hs_hchan) {
675 struct hci_chan *hs_hchan = chan->hs_hchan;
676
677 BT_DBG("chan %p disconnect hs_hchan %p", chan, hs_hchan);
678 amp_disconnect_logical_link(hs_hchan);
679 }
680
681 if (test_bit(CONF_NOT_COMPLETE, &chan->conf_state))
682 return;
683
684 switch (chan->mode) {
685 case L2CAP_MODE_BASIC:
686 break;
687
688 case L2CAP_MODE_LE_FLOWCTL:
689 case L2CAP_MODE_EXT_FLOWCTL:
690 skb_queue_purge(&chan->tx_q);
691 break;
692
693 case L2CAP_MODE_ERTM:
694 __clear_retrans_timer(chan);
695 __clear_monitor_timer(chan);
696 __clear_ack_timer(chan);
697
698 skb_queue_purge(&chan->srej_q);
699
700 l2cap_seq_list_free(&chan->srej_list);
701 l2cap_seq_list_free(&chan->retrans_list);
702 fallthrough;
703
704 case L2CAP_MODE_STREAMING:
705 skb_queue_purge(&chan->tx_q);
706 break;
707 }
708}
709EXPORT_SYMBOL_GPL(l2cap_chan_del);
710
711static void __l2cap_chan_list_id(struct l2cap_conn *conn, u16 id,
712 l2cap_chan_func_t func, void *data)
713{
714 struct l2cap_chan *chan, *l;
715
716 list_for_each_entry_safe(chan, l, &conn->chan_l, list) {
717 if (chan->ident == id)
718 func(chan, data);
719 }
720}
721
722static void __l2cap_chan_list(struct l2cap_conn *conn, l2cap_chan_func_t func,
723 void *data)
724{
725 struct l2cap_chan *chan;
726
727 list_for_each_entry(chan, &conn->chan_l, list) {
728 func(chan, data);
729 }
730}
731
732void l2cap_chan_list(struct l2cap_conn *conn, l2cap_chan_func_t func,
733 void *data)
734{
735 if (!conn)
736 return;
737
738 mutex_lock(&conn->chan_lock);
739 __l2cap_chan_list(conn, func, data);
740 mutex_unlock(&conn->chan_lock);
741}
742
743EXPORT_SYMBOL_GPL(l2cap_chan_list);
744
745static void l2cap_conn_update_id_addr(struct work_struct *work)
746{
747 struct l2cap_conn *conn = container_of(work, struct l2cap_conn,
748 id_addr_timer.work);
749 struct hci_conn *hcon = conn->hcon;
750 struct l2cap_chan *chan;
751
752 mutex_lock(&conn->chan_lock);
753
754 list_for_each_entry(chan, &conn->chan_l, list) {
755 l2cap_chan_lock(chan);
756 bacpy(&chan->dst, &hcon->dst);
757 chan->dst_type = bdaddr_dst_type(hcon);
758 l2cap_chan_unlock(chan);
759 }
760
761 mutex_unlock(&conn->chan_lock);
762}
763
764static void l2cap_chan_le_connect_reject(struct l2cap_chan *chan)
765{
766 struct l2cap_conn *conn = chan->conn;
767 struct l2cap_le_conn_rsp rsp;
768 u16 result;
769
770 if (test_bit(FLAG_DEFER_SETUP, &chan->flags))
771 result = L2CAP_CR_LE_AUTHORIZATION;
772 else
773 result = L2CAP_CR_LE_BAD_PSM;
774
775 l2cap_state_change(chan, BT_DISCONN);
776
777 rsp.dcid = cpu_to_le16(chan->scid);
778 rsp.mtu = cpu_to_le16(chan->imtu);
779 rsp.mps = cpu_to_le16(chan->mps);
780 rsp.credits = cpu_to_le16(chan->rx_credits);
781 rsp.result = cpu_to_le16(result);
782
783 l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CONN_RSP, sizeof(rsp),
784 &rsp);
785}
786
787static void l2cap_chan_ecred_connect_reject(struct l2cap_chan *chan)
788{
789 l2cap_state_change(chan, BT_DISCONN);
790
791 __l2cap_ecred_conn_rsp_defer(chan);
792}
793
794static void l2cap_chan_connect_reject(struct l2cap_chan *chan)
795{
796 struct l2cap_conn *conn = chan->conn;
797 struct l2cap_conn_rsp rsp;
798 u16 result;
799
800 if (test_bit(FLAG_DEFER_SETUP, &chan->flags))
801 result = L2CAP_CR_SEC_BLOCK;
802 else
803 result = L2CAP_CR_BAD_PSM;
804
805 l2cap_state_change(chan, BT_DISCONN);
806
807 rsp.scid = cpu_to_le16(chan->dcid);
808 rsp.dcid = cpu_to_le16(chan->scid);
809 rsp.result = cpu_to_le16(result);
810 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
811
812 l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_RSP, sizeof(rsp), &rsp);
813}
814
815void l2cap_chan_close(struct l2cap_chan *chan, int reason)
816{
817 struct l2cap_conn *conn = chan->conn;
818
819 BT_DBG("chan %p state %s", chan, state_to_string(chan->state));
820
821 switch (chan->state) {
822 case BT_LISTEN:
823 chan->ops->teardown(chan, 0);
824 break;
825
826 case BT_CONNECTED:
827 case BT_CONFIG:
828 if (chan->chan_type == L2CAP_CHAN_CONN_ORIENTED) {
829 __set_chan_timer(chan, chan->ops->get_sndtimeo(chan));
830 l2cap_send_disconn_req(chan, reason);
831 } else
832 l2cap_chan_del(chan, reason);
833 break;
834
835 case BT_CONNECT2:
836 if (chan->chan_type == L2CAP_CHAN_CONN_ORIENTED) {
837 if (conn->hcon->type == ACL_LINK)
838 l2cap_chan_connect_reject(chan);
839 else if (conn->hcon->type == LE_LINK) {
840 switch (chan->mode) {
841 case L2CAP_MODE_LE_FLOWCTL:
842 l2cap_chan_le_connect_reject(chan);
843 break;
844 case L2CAP_MODE_EXT_FLOWCTL:
845 l2cap_chan_ecred_connect_reject(chan);
846 return;
847 }
848 }
849 }
850
851 l2cap_chan_del(chan, reason);
852 break;
853
854 case BT_CONNECT:
855 case BT_DISCONN:
856 l2cap_chan_del(chan, reason);
857 break;
858
859 default:
860 chan->ops->teardown(chan, 0);
861 break;
862 }
863}
864EXPORT_SYMBOL(l2cap_chan_close);
865
866static inline u8 l2cap_get_auth_type(struct l2cap_chan *chan)
867{
868 switch (chan->chan_type) {
869 case L2CAP_CHAN_RAW:
870 switch (chan->sec_level) {
871 case BT_SECURITY_HIGH:
872 case BT_SECURITY_FIPS:
873 return HCI_AT_DEDICATED_BONDING_MITM;
874 case BT_SECURITY_MEDIUM:
875 return HCI_AT_DEDICATED_BONDING;
876 default:
877 return HCI_AT_NO_BONDING;
878 }
879 break;
880 case L2CAP_CHAN_CONN_LESS:
881 if (chan->psm == cpu_to_le16(L2CAP_PSM_3DSP)) {
882 if (chan->sec_level == BT_SECURITY_LOW)
883 chan->sec_level = BT_SECURITY_SDP;
884 }
885 if (chan->sec_level == BT_SECURITY_HIGH ||
886 chan->sec_level == BT_SECURITY_FIPS)
887 return HCI_AT_NO_BONDING_MITM;
888 else
889 return HCI_AT_NO_BONDING;
890 break;
891 case L2CAP_CHAN_CONN_ORIENTED:
892 if (chan->psm == cpu_to_le16(L2CAP_PSM_SDP)) {
893 if (chan->sec_level == BT_SECURITY_LOW)
894 chan->sec_level = BT_SECURITY_SDP;
895
896 if (chan->sec_level == BT_SECURITY_HIGH ||
897 chan->sec_level == BT_SECURITY_FIPS)
898 return HCI_AT_NO_BONDING_MITM;
899 else
900 return HCI_AT_NO_BONDING;
901 }
902 fallthrough;
903
904 default:
905 switch (chan->sec_level) {
906 case BT_SECURITY_HIGH:
907 case BT_SECURITY_FIPS:
908 return HCI_AT_GENERAL_BONDING_MITM;
909 case BT_SECURITY_MEDIUM:
910 return HCI_AT_GENERAL_BONDING;
911 default:
912 return HCI_AT_NO_BONDING;
913 }
914 break;
915 }
916}
917
918/* Service level security */
919int l2cap_chan_check_security(struct l2cap_chan *chan, bool initiator)
920{
921 struct l2cap_conn *conn = chan->conn;
922 __u8 auth_type;
923
924 if (conn->hcon->type == LE_LINK)
925 return smp_conn_security(conn->hcon, chan->sec_level);
926
927 auth_type = l2cap_get_auth_type(chan);
928
929 return hci_conn_security(conn->hcon, chan->sec_level, auth_type,
930 initiator);
931}
932
933static u8 l2cap_get_ident(struct l2cap_conn *conn)
934{
935 u8 id;
936
937 /* Get next available identificator.
938 * 1 - 128 are used by kernel.
939 * 129 - 199 are reserved.
940 * 200 - 254 are used by utilities like l2ping, etc.
941 */
942
943 mutex_lock(&conn->ident_lock);
944
945 if (++conn->tx_ident > 128)
946 conn->tx_ident = 1;
947
948 id = conn->tx_ident;
949
950 mutex_unlock(&conn->ident_lock);
951
952 return id;
953}
954
955static void l2cap_send_cmd(struct l2cap_conn *conn, u8 ident, u8 code, u16 len,
956 void *data)
957{
958 struct sk_buff *skb = l2cap_build_cmd(conn, code, ident, len, data);
959 u8 flags;
960
961 BT_DBG("code 0x%2.2x", code);
962
963 if (!skb)
964 return;
965
966 /* Use NO_FLUSH if supported or we have an LE link (which does
967 * not support auto-flushing packets) */
968 if (lmp_no_flush_capable(conn->hcon->hdev) ||
969 conn->hcon->type == LE_LINK)
970 flags = ACL_START_NO_FLUSH;
971 else
972 flags = ACL_START;
973
974 bt_cb(skb)->force_active = BT_POWER_FORCE_ACTIVE_ON;
975 skb->priority = HCI_PRIO_MAX;
976
977 hci_send_acl(conn->hchan, skb, flags);
978}
979
980static bool __chan_is_moving(struct l2cap_chan *chan)
981{
982 return chan->move_state != L2CAP_MOVE_STABLE &&
983 chan->move_state != L2CAP_MOVE_WAIT_PREPARE;
984}
985
986static void l2cap_do_send(struct l2cap_chan *chan, struct sk_buff *skb)
987{
988 struct hci_conn *hcon = chan->conn->hcon;
989 u16 flags;
990
991 BT_DBG("chan %p, skb %p len %d priority %u", chan, skb, skb->len,
992 skb->priority);
993
994 if (chan->hs_hcon && !__chan_is_moving(chan)) {
995 if (chan->hs_hchan)
996 hci_send_acl(chan->hs_hchan, skb, ACL_COMPLETE);
997 else
998 kfree_skb(skb);
999
1000 return;
1001 }
1002
1003 /* Use NO_FLUSH for LE links (where this is the only option) or
1004 * if the BR/EDR link supports it and flushing has not been
1005 * explicitly requested (through FLAG_FLUSHABLE).
1006 */
1007 if (hcon->type == LE_LINK ||
1008 (!test_bit(FLAG_FLUSHABLE, &chan->flags) &&
1009 lmp_no_flush_capable(hcon->hdev)))
1010 flags = ACL_START_NO_FLUSH;
1011 else
1012 flags = ACL_START;
1013
1014 bt_cb(skb)->force_active = test_bit(FLAG_FORCE_ACTIVE, &chan->flags);
1015 hci_send_acl(chan->conn->hchan, skb, flags);
1016}
1017
1018static void __unpack_enhanced_control(u16 enh, struct l2cap_ctrl *control)
1019{
1020 control->reqseq = (enh & L2CAP_CTRL_REQSEQ) >> L2CAP_CTRL_REQSEQ_SHIFT;
1021 control->final = (enh & L2CAP_CTRL_FINAL) >> L2CAP_CTRL_FINAL_SHIFT;
1022
1023 if (enh & L2CAP_CTRL_FRAME_TYPE) {
1024 /* S-Frame */
1025 control->sframe = 1;
1026 control->poll = (enh & L2CAP_CTRL_POLL) >> L2CAP_CTRL_POLL_SHIFT;
1027 control->super = (enh & L2CAP_CTRL_SUPERVISE) >> L2CAP_CTRL_SUPER_SHIFT;
1028
1029 control->sar = 0;
1030 control->txseq = 0;
1031 } else {
1032 /* I-Frame */
1033 control->sframe = 0;
1034 control->sar = (enh & L2CAP_CTRL_SAR) >> L2CAP_CTRL_SAR_SHIFT;
1035 control->txseq = (enh & L2CAP_CTRL_TXSEQ) >> L2CAP_CTRL_TXSEQ_SHIFT;
1036
1037 control->poll = 0;
1038 control->super = 0;
1039 }
1040}
1041
1042static void __unpack_extended_control(u32 ext, struct l2cap_ctrl *control)
1043{
1044 control->reqseq = (ext & L2CAP_EXT_CTRL_REQSEQ) >> L2CAP_EXT_CTRL_REQSEQ_SHIFT;
1045 control->final = (ext & L2CAP_EXT_CTRL_FINAL) >> L2CAP_EXT_CTRL_FINAL_SHIFT;
1046
1047 if (ext & L2CAP_EXT_CTRL_FRAME_TYPE) {
1048 /* S-Frame */
1049 control->sframe = 1;
1050 control->poll = (ext & L2CAP_EXT_CTRL_POLL) >> L2CAP_EXT_CTRL_POLL_SHIFT;
1051 control->super = (ext & L2CAP_EXT_CTRL_SUPERVISE) >> L2CAP_EXT_CTRL_SUPER_SHIFT;
1052
1053 control->sar = 0;
1054 control->txseq = 0;
1055 } else {
1056 /* I-Frame */
1057 control->sframe = 0;
1058 control->sar = (ext & L2CAP_EXT_CTRL_SAR) >> L2CAP_EXT_CTRL_SAR_SHIFT;
1059 control->txseq = (ext & L2CAP_EXT_CTRL_TXSEQ) >> L2CAP_EXT_CTRL_TXSEQ_SHIFT;
1060
1061 control->poll = 0;
1062 control->super = 0;
1063 }
1064}
1065
1066static inline void __unpack_control(struct l2cap_chan *chan,
1067 struct sk_buff *skb)
1068{
1069 if (test_bit(FLAG_EXT_CTRL, &chan->flags)) {
1070 __unpack_extended_control(get_unaligned_le32(skb->data),
1071 &bt_cb(skb)->l2cap);
1072 skb_pull(skb, L2CAP_EXT_CTRL_SIZE);
1073 } else {
1074 __unpack_enhanced_control(get_unaligned_le16(skb->data),
1075 &bt_cb(skb)->l2cap);
1076 skb_pull(skb, L2CAP_ENH_CTRL_SIZE);
1077 }
1078}
1079
1080static u32 __pack_extended_control(struct l2cap_ctrl *control)
1081{
1082 u32 packed;
1083
1084 packed = control->reqseq << L2CAP_EXT_CTRL_REQSEQ_SHIFT;
1085 packed |= control->final << L2CAP_EXT_CTRL_FINAL_SHIFT;
1086
1087 if (control->sframe) {
1088 packed |= control->poll << L2CAP_EXT_CTRL_POLL_SHIFT;
1089 packed |= control->super << L2CAP_EXT_CTRL_SUPER_SHIFT;
1090 packed |= L2CAP_EXT_CTRL_FRAME_TYPE;
1091 } else {
1092 packed |= control->sar << L2CAP_EXT_CTRL_SAR_SHIFT;
1093 packed |= control->txseq << L2CAP_EXT_CTRL_TXSEQ_SHIFT;
1094 }
1095
1096 return packed;
1097}
1098
1099static u16 __pack_enhanced_control(struct l2cap_ctrl *control)
1100{
1101 u16 packed;
1102
1103 packed = control->reqseq << L2CAP_CTRL_REQSEQ_SHIFT;
1104 packed |= control->final << L2CAP_CTRL_FINAL_SHIFT;
1105
1106 if (control->sframe) {
1107 packed |= control->poll << L2CAP_CTRL_POLL_SHIFT;
1108 packed |= control->super << L2CAP_CTRL_SUPER_SHIFT;
1109 packed |= L2CAP_CTRL_FRAME_TYPE;
1110 } else {
1111 packed |= control->sar << L2CAP_CTRL_SAR_SHIFT;
1112 packed |= control->txseq << L2CAP_CTRL_TXSEQ_SHIFT;
1113 }
1114
1115 return packed;
1116}
1117
1118static inline void __pack_control(struct l2cap_chan *chan,
1119 struct l2cap_ctrl *control,
1120 struct sk_buff *skb)
1121{
1122 if (test_bit(FLAG_EXT_CTRL, &chan->flags)) {
1123 put_unaligned_le32(__pack_extended_control(control),
1124 skb->data + L2CAP_HDR_SIZE);
1125 } else {
1126 put_unaligned_le16(__pack_enhanced_control(control),
1127 skb->data + L2CAP_HDR_SIZE);
1128 }
1129}
1130
1131static inline unsigned int __ertm_hdr_size(struct l2cap_chan *chan)
1132{
1133 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
1134 return L2CAP_EXT_HDR_SIZE;
1135 else
1136 return L2CAP_ENH_HDR_SIZE;
1137}
1138
1139static struct sk_buff *l2cap_create_sframe_pdu(struct l2cap_chan *chan,
1140 u32 control)
1141{
1142 struct sk_buff *skb;
1143 struct l2cap_hdr *lh;
1144 int hlen = __ertm_hdr_size(chan);
1145
1146 if (chan->fcs == L2CAP_FCS_CRC16)
1147 hlen += L2CAP_FCS_SIZE;
1148
1149 skb = bt_skb_alloc(hlen, GFP_KERNEL);
1150
1151 if (!skb)
1152 return ERR_PTR(-ENOMEM);
1153
1154 lh = skb_put(skb, L2CAP_HDR_SIZE);
1155 lh->len = cpu_to_le16(hlen - L2CAP_HDR_SIZE);
1156 lh->cid = cpu_to_le16(chan->dcid);
1157
1158 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
1159 put_unaligned_le32(control, skb_put(skb, L2CAP_EXT_CTRL_SIZE));
1160 else
1161 put_unaligned_le16(control, skb_put(skb, L2CAP_ENH_CTRL_SIZE));
1162
1163 if (chan->fcs == L2CAP_FCS_CRC16) {
1164 u16 fcs = crc16(0, (u8 *)skb->data, skb->len);
1165 put_unaligned_le16(fcs, skb_put(skb, L2CAP_FCS_SIZE));
1166 }
1167
1168 skb->priority = HCI_PRIO_MAX;
1169 return skb;
1170}
1171
1172static void l2cap_send_sframe(struct l2cap_chan *chan,
1173 struct l2cap_ctrl *control)
1174{
1175 struct sk_buff *skb;
1176 u32 control_field;
1177
1178 BT_DBG("chan %p, control %p", chan, control);
1179
1180 if (!control->sframe)
1181 return;
1182
1183 if (__chan_is_moving(chan))
1184 return;
1185
1186 if (test_and_clear_bit(CONN_SEND_FBIT, &chan->conn_state) &&
1187 !control->poll)
1188 control->final = 1;
1189
1190 if (control->super == L2CAP_SUPER_RR)
1191 clear_bit(CONN_RNR_SENT, &chan->conn_state);
1192 else if (control->super == L2CAP_SUPER_RNR)
1193 set_bit(CONN_RNR_SENT, &chan->conn_state);
1194
1195 if (control->super != L2CAP_SUPER_SREJ) {
1196 chan->last_acked_seq = control->reqseq;
1197 __clear_ack_timer(chan);
1198 }
1199
1200 BT_DBG("reqseq %d, final %d, poll %d, super %d", control->reqseq,
1201 control->final, control->poll, control->super);
1202
1203 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
1204 control_field = __pack_extended_control(control);
1205 else
1206 control_field = __pack_enhanced_control(control);
1207
1208 skb = l2cap_create_sframe_pdu(chan, control_field);
1209 if (!IS_ERR(skb))
1210 l2cap_do_send(chan, skb);
1211}
1212
1213static void l2cap_send_rr_or_rnr(struct l2cap_chan *chan, bool poll)
1214{
1215 struct l2cap_ctrl control;
1216
1217 BT_DBG("chan %p, poll %d", chan, poll);
1218
1219 memset(&control, 0, sizeof(control));
1220 control.sframe = 1;
1221 control.poll = poll;
1222
1223 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state))
1224 control.super = L2CAP_SUPER_RNR;
1225 else
1226 control.super = L2CAP_SUPER_RR;
1227
1228 control.reqseq = chan->buffer_seq;
1229 l2cap_send_sframe(chan, &control);
1230}
1231
1232static inline int __l2cap_no_conn_pending(struct l2cap_chan *chan)
1233{
1234 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED)
1235 return true;
1236
1237 return !test_bit(CONF_CONNECT_PEND, &chan->conf_state);
1238}
1239
1240static bool __amp_capable(struct l2cap_chan *chan)
1241{
1242 struct l2cap_conn *conn = chan->conn;
1243 struct hci_dev *hdev;
1244 bool amp_available = false;
1245
1246 if (!(conn->local_fixed_chan & L2CAP_FC_A2MP))
1247 return false;
1248
1249 if (!(conn->remote_fixed_chan & L2CAP_FC_A2MP))
1250 return false;
1251
1252 read_lock(&hci_dev_list_lock);
1253 list_for_each_entry(hdev, &hci_dev_list, list) {
1254 if (hdev->amp_type != AMP_TYPE_BREDR &&
1255 test_bit(HCI_UP, &hdev->flags)) {
1256 amp_available = true;
1257 break;
1258 }
1259 }
1260 read_unlock(&hci_dev_list_lock);
1261
1262 if (chan->chan_policy == BT_CHANNEL_POLICY_AMP_PREFERRED)
1263 return amp_available;
1264
1265 return false;
1266}
1267
1268static bool l2cap_check_efs(struct l2cap_chan *chan)
1269{
1270 /* Check EFS parameters */
1271 return true;
1272}
1273
1274void l2cap_send_conn_req(struct l2cap_chan *chan)
1275{
1276 struct l2cap_conn *conn = chan->conn;
1277 struct l2cap_conn_req req;
1278
1279 req.scid = cpu_to_le16(chan->scid);
1280 req.psm = chan->psm;
1281
1282 chan->ident = l2cap_get_ident(conn);
1283
1284 set_bit(CONF_CONNECT_PEND, &chan->conf_state);
1285
1286 l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_REQ, sizeof(req), &req);
1287}
1288
1289static void l2cap_send_create_chan_req(struct l2cap_chan *chan, u8 amp_id)
1290{
1291 struct l2cap_create_chan_req req;
1292 req.scid = cpu_to_le16(chan->scid);
1293 req.psm = chan->psm;
1294 req.amp_id = amp_id;
1295
1296 chan->ident = l2cap_get_ident(chan->conn);
1297
1298 l2cap_send_cmd(chan->conn, chan->ident, L2CAP_CREATE_CHAN_REQ,
1299 sizeof(req), &req);
1300}
1301
1302static void l2cap_move_setup(struct l2cap_chan *chan)
1303{
1304 struct sk_buff *skb;
1305
1306 BT_DBG("chan %p", chan);
1307
1308 if (chan->mode != L2CAP_MODE_ERTM)
1309 return;
1310
1311 __clear_retrans_timer(chan);
1312 __clear_monitor_timer(chan);
1313 __clear_ack_timer(chan);
1314
1315 chan->retry_count = 0;
1316 skb_queue_walk(&chan->tx_q, skb) {
1317 if (bt_cb(skb)->l2cap.retries)
1318 bt_cb(skb)->l2cap.retries = 1;
1319 else
1320 break;
1321 }
1322
1323 chan->expected_tx_seq = chan->buffer_seq;
1324
1325 clear_bit(CONN_REJ_ACT, &chan->conn_state);
1326 clear_bit(CONN_SREJ_ACT, &chan->conn_state);
1327 l2cap_seq_list_clear(&chan->retrans_list);
1328 l2cap_seq_list_clear(&chan->srej_list);
1329 skb_queue_purge(&chan->srej_q);
1330
1331 chan->tx_state = L2CAP_TX_STATE_XMIT;
1332 chan->rx_state = L2CAP_RX_STATE_MOVE;
1333
1334 set_bit(CONN_REMOTE_BUSY, &chan->conn_state);
1335}
1336
1337static void l2cap_move_done(struct l2cap_chan *chan)
1338{
1339 u8 move_role = chan->move_role;
1340 BT_DBG("chan %p", chan);
1341
1342 chan->move_state = L2CAP_MOVE_STABLE;
1343 chan->move_role = L2CAP_MOVE_ROLE_NONE;
1344
1345 if (chan->mode != L2CAP_MODE_ERTM)
1346 return;
1347
1348 switch (move_role) {
1349 case L2CAP_MOVE_ROLE_INITIATOR:
1350 l2cap_tx(chan, NULL, NULL, L2CAP_EV_EXPLICIT_POLL);
1351 chan->rx_state = L2CAP_RX_STATE_WAIT_F;
1352 break;
1353 case L2CAP_MOVE_ROLE_RESPONDER:
1354 chan->rx_state = L2CAP_RX_STATE_WAIT_P;
1355 break;
1356 }
1357}
1358
1359static void l2cap_chan_ready(struct l2cap_chan *chan)
1360{
1361 /* The channel may have already been flagged as connected in
1362 * case of receiving data before the L2CAP info req/rsp
1363 * procedure is complete.
1364 */
1365 if (chan->state == BT_CONNECTED)
1366 return;
1367
1368 /* This clears all conf flags, including CONF_NOT_COMPLETE */
1369 chan->conf_state = 0;
1370 __clear_chan_timer(chan);
1371
1372 switch (chan->mode) {
1373 case L2CAP_MODE_LE_FLOWCTL:
1374 case L2CAP_MODE_EXT_FLOWCTL:
1375 if (!chan->tx_credits)
1376 chan->ops->suspend(chan);
1377 break;
1378 }
1379
1380 chan->state = BT_CONNECTED;
1381
1382 chan->ops->ready(chan);
1383}
1384
1385static void l2cap_le_connect(struct l2cap_chan *chan)
1386{
1387 struct l2cap_conn *conn = chan->conn;
1388 struct l2cap_le_conn_req req;
1389
1390 if (test_and_set_bit(FLAG_LE_CONN_REQ_SENT, &chan->flags))
1391 return;
1392
1393 if (!chan->imtu)
1394 chan->imtu = chan->conn->mtu;
1395
1396 l2cap_le_flowctl_init(chan, 0);
1397
1398 memset(&req, 0, sizeof(req));
1399 req.psm = chan->psm;
1400 req.scid = cpu_to_le16(chan->scid);
1401 req.mtu = cpu_to_le16(chan->imtu);
1402 req.mps = cpu_to_le16(chan->mps);
1403 req.credits = cpu_to_le16(chan->rx_credits);
1404
1405 chan->ident = l2cap_get_ident(conn);
1406
1407 l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CONN_REQ,
1408 sizeof(req), &req);
1409}
1410
1411struct l2cap_ecred_conn_data {
1412 struct {
1413 struct l2cap_ecred_conn_req req;
1414 __le16 scid[5];
1415 } __packed pdu;
1416 struct l2cap_chan *chan;
1417 struct pid *pid;
1418 int count;
1419};
1420
1421static void l2cap_ecred_defer_connect(struct l2cap_chan *chan, void *data)
1422{
1423 struct l2cap_ecred_conn_data *conn = data;
1424 struct pid *pid;
1425
1426 if (chan == conn->chan)
1427 return;
1428
1429 if (!test_and_clear_bit(FLAG_DEFER_SETUP, &chan->flags))
1430 return;
1431
1432 pid = chan->ops->get_peer_pid(chan);
1433
1434 /* Only add deferred channels with the same PID/PSM */
1435 if (conn->pid != pid || chan->psm != conn->chan->psm || chan->ident ||
1436 chan->mode != L2CAP_MODE_EXT_FLOWCTL || chan->state != BT_CONNECT)
1437 return;
1438
1439 if (test_and_set_bit(FLAG_ECRED_CONN_REQ_SENT, &chan->flags))
1440 return;
1441
1442 l2cap_ecred_init(chan, 0);
1443
1444 /* Set the same ident so we can match on the rsp */
1445 chan->ident = conn->chan->ident;
1446
1447 /* Include all channels deferred */
1448 conn->pdu.scid[conn->count] = cpu_to_le16(chan->scid);
1449
1450 conn->count++;
1451}
1452
1453static void l2cap_ecred_connect(struct l2cap_chan *chan)
1454{
1455 struct l2cap_conn *conn = chan->conn;
1456 struct l2cap_ecred_conn_data data;
1457
1458 if (test_bit(FLAG_DEFER_SETUP, &chan->flags))
1459 return;
1460
1461 if (test_and_set_bit(FLAG_ECRED_CONN_REQ_SENT, &chan->flags))
1462 return;
1463
1464 l2cap_ecred_init(chan, 0);
1465
1466 memset(&data, 0, sizeof(data));
1467 data.pdu.req.psm = chan->psm;
1468 data.pdu.req.mtu = cpu_to_le16(chan->imtu);
1469 data.pdu.req.mps = cpu_to_le16(chan->mps);
1470 data.pdu.req.credits = cpu_to_le16(chan->rx_credits);
1471 data.pdu.scid[0] = cpu_to_le16(chan->scid);
1472
1473 chan->ident = l2cap_get_ident(conn);
1474
1475 data.count = 1;
1476 data.chan = chan;
1477 data.pid = chan->ops->get_peer_pid(chan);
1478
1479 __l2cap_chan_list(conn, l2cap_ecred_defer_connect, &data);
1480
1481 l2cap_send_cmd(conn, chan->ident, L2CAP_ECRED_CONN_REQ,
1482 sizeof(data.pdu.req) + data.count * sizeof(__le16),
1483 &data.pdu);
1484}
1485
1486static void l2cap_le_start(struct l2cap_chan *chan)
1487{
1488 struct l2cap_conn *conn = chan->conn;
1489
1490 if (!smp_conn_security(conn->hcon, chan->sec_level))
1491 return;
1492
1493 if (!chan->psm) {
1494 l2cap_chan_ready(chan);
1495 return;
1496 }
1497
1498 if (chan->state == BT_CONNECT) {
1499 if (chan->mode == L2CAP_MODE_EXT_FLOWCTL)
1500 l2cap_ecred_connect(chan);
1501 else
1502 l2cap_le_connect(chan);
1503 }
1504}
1505
1506static void l2cap_start_connection(struct l2cap_chan *chan)
1507{
1508 if (__amp_capable(chan)) {
1509 BT_DBG("chan %p AMP capable: discover AMPs", chan);
1510 a2mp_discover_amp(chan);
1511 } else if (chan->conn->hcon->type == LE_LINK) {
1512 l2cap_le_start(chan);
1513 } else {
1514 l2cap_send_conn_req(chan);
1515 }
1516}
1517
1518static void l2cap_request_info(struct l2cap_conn *conn)
1519{
1520 struct l2cap_info_req req;
1521
1522 if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT)
1523 return;
1524
1525 req.type = cpu_to_le16(L2CAP_IT_FEAT_MASK);
1526
1527 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_SENT;
1528 conn->info_ident = l2cap_get_ident(conn);
1529
1530 schedule_delayed_work(&conn->info_timer, L2CAP_INFO_TIMEOUT);
1531
1532 l2cap_send_cmd(conn, conn->info_ident, L2CAP_INFO_REQ,
1533 sizeof(req), &req);
1534}
1535
1536static bool l2cap_check_enc_key_size(struct hci_conn *hcon)
1537{
1538 /* The minimum encryption key size needs to be enforced by the
1539 * host stack before establishing any L2CAP connections. The
1540 * specification in theory allows a minimum of 1, but to align
1541 * BR/EDR and LE transports, a minimum of 7 is chosen.
1542 *
1543 * This check might also be called for unencrypted connections
1544 * that have no key size requirements. Ensure that the link is
1545 * actually encrypted before enforcing a key size.
1546 */
1547 int min_key_size = hcon->hdev->min_enc_key_size;
1548
1549 /* On FIPS security level, key size must be 16 bytes */
1550 if (hcon->sec_level == BT_SECURITY_FIPS)
1551 min_key_size = 16;
1552
1553 return (!test_bit(HCI_CONN_ENCRYPT, &hcon->flags) ||
1554 hcon->enc_key_size >= min_key_size);
1555}
1556
1557static void l2cap_do_start(struct l2cap_chan *chan)
1558{
1559 struct l2cap_conn *conn = chan->conn;
1560
1561 if (conn->hcon->type == LE_LINK) {
1562 l2cap_le_start(chan);
1563 return;
1564 }
1565
1566 if (!(conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT)) {
1567 l2cap_request_info(conn);
1568 return;
1569 }
1570
1571 if (!(conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE))
1572 return;
1573
1574 if (!l2cap_chan_check_security(chan, true) ||
1575 !__l2cap_no_conn_pending(chan))
1576 return;
1577
1578 if (l2cap_check_enc_key_size(conn->hcon))
1579 l2cap_start_connection(chan);
1580 else
1581 __set_chan_timer(chan, L2CAP_DISC_TIMEOUT);
1582}
1583
1584static inline int l2cap_mode_supported(__u8 mode, __u32 feat_mask)
1585{
1586 u32 local_feat_mask = l2cap_feat_mask;
1587 if (!disable_ertm)
1588 local_feat_mask |= L2CAP_FEAT_ERTM | L2CAP_FEAT_STREAMING;
1589
1590 switch (mode) {
1591 case L2CAP_MODE_ERTM:
1592 return L2CAP_FEAT_ERTM & feat_mask & local_feat_mask;
1593 case L2CAP_MODE_STREAMING:
1594 return L2CAP_FEAT_STREAMING & feat_mask & local_feat_mask;
1595 default:
1596 return 0x00;
1597 }
1598}
1599
1600static void l2cap_send_disconn_req(struct l2cap_chan *chan, int err)
1601{
1602 struct l2cap_conn *conn = chan->conn;
1603 struct l2cap_disconn_req req;
1604
1605 if (!conn)
1606 return;
1607
1608 if (chan->mode == L2CAP_MODE_ERTM && chan->state == BT_CONNECTED) {
1609 __clear_retrans_timer(chan);
1610 __clear_monitor_timer(chan);
1611 __clear_ack_timer(chan);
1612 }
1613
1614 if (chan->scid == L2CAP_CID_A2MP) {
1615 l2cap_state_change(chan, BT_DISCONN);
1616 return;
1617 }
1618
1619 req.dcid = cpu_to_le16(chan->dcid);
1620 req.scid = cpu_to_le16(chan->scid);
1621 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_DISCONN_REQ,
1622 sizeof(req), &req);
1623
1624 l2cap_state_change_and_error(chan, BT_DISCONN, err);
1625}
1626
1627/* ---- L2CAP connections ---- */
1628static void l2cap_conn_start(struct l2cap_conn *conn)
1629{
1630 struct l2cap_chan *chan, *tmp;
1631
1632 BT_DBG("conn %p", conn);
1633
1634 mutex_lock(&conn->chan_lock);
1635
1636 list_for_each_entry_safe(chan, tmp, &conn->chan_l, list) {
1637 l2cap_chan_lock(chan);
1638
1639 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) {
1640 l2cap_chan_ready(chan);
1641 l2cap_chan_unlock(chan);
1642 continue;
1643 }
1644
1645 if (chan->state == BT_CONNECT) {
1646 if (!l2cap_chan_check_security(chan, true) ||
1647 !__l2cap_no_conn_pending(chan)) {
1648 l2cap_chan_unlock(chan);
1649 continue;
1650 }
1651
1652 if (!l2cap_mode_supported(chan->mode, conn->feat_mask)
1653 && test_bit(CONF_STATE2_DEVICE,
1654 &chan->conf_state)) {
1655 l2cap_chan_close(chan, ECONNRESET);
1656 l2cap_chan_unlock(chan);
1657 continue;
1658 }
1659
1660 if (l2cap_check_enc_key_size(conn->hcon))
1661 l2cap_start_connection(chan);
1662 else
1663 l2cap_chan_close(chan, ECONNREFUSED);
1664
1665 } else if (chan->state == BT_CONNECT2) {
1666 struct l2cap_conn_rsp rsp;
1667 char buf[128];
1668 rsp.scid = cpu_to_le16(chan->dcid);
1669 rsp.dcid = cpu_to_le16(chan->scid);
1670
1671 if (l2cap_chan_check_security(chan, false)) {
1672 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) {
1673 rsp.result = cpu_to_le16(L2CAP_CR_PEND);
1674 rsp.status = cpu_to_le16(L2CAP_CS_AUTHOR_PEND);
1675 chan->ops->defer(chan);
1676
1677 } else {
1678 l2cap_state_change(chan, BT_CONFIG);
1679 rsp.result = cpu_to_le16(L2CAP_CR_SUCCESS);
1680 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
1681 }
1682 } else {
1683 rsp.result = cpu_to_le16(L2CAP_CR_PEND);
1684 rsp.status = cpu_to_le16(L2CAP_CS_AUTHEN_PEND);
1685 }
1686
1687 l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_RSP,
1688 sizeof(rsp), &rsp);
1689
1690 if (test_bit(CONF_REQ_SENT, &chan->conf_state) ||
1691 rsp.result != L2CAP_CR_SUCCESS) {
1692 l2cap_chan_unlock(chan);
1693 continue;
1694 }
1695
1696 set_bit(CONF_REQ_SENT, &chan->conf_state);
1697 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
1698 l2cap_build_conf_req(chan, buf, sizeof(buf)), buf);
1699 chan->num_conf_req++;
1700 }
1701
1702 l2cap_chan_unlock(chan);
1703 }
1704
1705 mutex_unlock(&conn->chan_lock);
1706}
1707
1708static void l2cap_le_conn_ready(struct l2cap_conn *conn)
1709{
1710 struct hci_conn *hcon = conn->hcon;
1711 struct hci_dev *hdev = hcon->hdev;
1712
1713 BT_DBG("%s conn %p", hdev->name, conn);
1714
1715 /* For outgoing pairing which doesn't necessarily have an
1716 * associated socket (e.g. mgmt_pair_device).
1717 */
1718 if (hcon->out)
1719 smp_conn_security(hcon, hcon->pending_sec_level);
1720
1721 /* For LE peripheral connections, make sure the connection interval
1722 * is in the range of the minimum and maximum interval that has
1723 * been configured for this connection. If not, then trigger
1724 * the connection update procedure.
1725 */
1726 if (hcon->role == HCI_ROLE_SLAVE &&
1727 (hcon->le_conn_interval < hcon->le_conn_min_interval ||
1728 hcon->le_conn_interval > hcon->le_conn_max_interval)) {
1729 struct l2cap_conn_param_update_req req;
1730
1731 req.min = cpu_to_le16(hcon->le_conn_min_interval);
1732 req.max = cpu_to_le16(hcon->le_conn_max_interval);
1733 req.latency = cpu_to_le16(hcon->le_conn_latency);
1734 req.to_multiplier = cpu_to_le16(hcon->le_supv_timeout);
1735
1736 l2cap_send_cmd(conn, l2cap_get_ident(conn),
1737 L2CAP_CONN_PARAM_UPDATE_REQ, sizeof(req), &req);
1738 }
1739}
1740
1741static void l2cap_conn_ready(struct l2cap_conn *conn)
1742{
1743 struct l2cap_chan *chan;
1744 struct hci_conn *hcon = conn->hcon;
1745
1746 BT_DBG("conn %p", conn);
1747
1748 if (hcon->type == ACL_LINK)
1749 l2cap_request_info(conn);
1750
1751 mutex_lock(&conn->chan_lock);
1752
1753 list_for_each_entry(chan, &conn->chan_l, list) {
1754
1755 l2cap_chan_lock(chan);
1756
1757 if (chan->scid == L2CAP_CID_A2MP) {
1758 l2cap_chan_unlock(chan);
1759 continue;
1760 }
1761
1762 if (hcon->type == LE_LINK) {
1763 l2cap_le_start(chan);
1764 } else if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) {
1765 if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE)
1766 l2cap_chan_ready(chan);
1767 } else if (chan->state == BT_CONNECT) {
1768 l2cap_do_start(chan);
1769 }
1770
1771 l2cap_chan_unlock(chan);
1772 }
1773
1774 mutex_unlock(&conn->chan_lock);
1775
1776 if (hcon->type == LE_LINK)
1777 l2cap_le_conn_ready(conn);
1778
1779 queue_work(hcon->hdev->workqueue, &conn->pending_rx_work);
1780}
1781
1782/* Notify sockets that we cannot guaranty reliability anymore */
1783static void l2cap_conn_unreliable(struct l2cap_conn *conn, int err)
1784{
1785 struct l2cap_chan *chan;
1786
1787 BT_DBG("conn %p", conn);
1788
1789 mutex_lock(&conn->chan_lock);
1790
1791 list_for_each_entry(chan, &conn->chan_l, list) {
1792 if (test_bit(FLAG_FORCE_RELIABLE, &chan->flags))
1793 l2cap_chan_set_err(chan, err);
1794 }
1795
1796 mutex_unlock(&conn->chan_lock);
1797}
1798
1799static void l2cap_info_timeout(struct work_struct *work)
1800{
1801 struct l2cap_conn *conn = container_of(work, struct l2cap_conn,
1802 info_timer.work);
1803
1804 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
1805 conn->info_ident = 0;
1806
1807 l2cap_conn_start(conn);
1808}
1809
1810/*
1811 * l2cap_user
1812 * External modules can register l2cap_user objects on l2cap_conn. The ->probe
1813 * callback is called during registration. The ->remove callback is called
1814 * during unregistration.
1815 * An l2cap_user object can either be explicitly unregistered or when the
1816 * underlying l2cap_conn object is deleted. This guarantees that l2cap->hcon,
1817 * l2cap->hchan, .. are valid as long as the remove callback hasn't been called.
1818 * External modules must own a reference to the l2cap_conn object if they intend
1819 * to call l2cap_unregister_user(). The l2cap_conn object might get destroyed at
1820 * any time if they don't.
1821 */
1822
1823int l2cap_register_user(struct l2cap_conn *conn, struct l2cap_user *user)
1824{
1825 struct hci_dev *hdev = conn->hcon->hdev;
1826 int ret;
1827
1828 /* We need to check whether l2cap_conn is registered. If it is not, we
1829 * must not register the l2cap_user. l2cap_conn_del() is unregisters
1830 * l2cap_conn objects, but doesn't provide its own locking. Instead, it
1831 * relies on the parent hci_conn object to be locked. This itself relies
1832 * on the hci_dev object to be locked. So we must lock the hci device
1833 * here, too. */
1834
1835 hci_dev_lock(hdev);
1836
1837 if (!list_empty(&user->list)) {
1838 ret = -EINVAL;
1839 goto out_unlock;
1840 }
1841
1842 /* conn->hchan is NULL after l2cap_conn_del() was called */
1843 if (!conn->hchan) {
1844 ret = -ENODEV;
1845 goto out_unlock;
1846 }
1847
1848 ret = user->probe(conn, user);
1849 if (ret)
1850 goto out_unlock;
1851
1852 list_add(&user->list, &conn->users);
1853 ret = 0;
1854
1855out_unlock:
1856 hci_dev_unlock(hdev);
1857 return ret;
1858}
1859EXPORT_SYMBOL(l2cap_register_user);
1860
1861void l2cap_unregister_user(struct l2cap_conn *conn, struct l2cap_user *user)
1862{
1863 struct hci_dev *hdev = conn->hcon->hdev;
1864
1865 hci_dev_lock(hdev);
1866
1867 if (list_empty(&user->list))
1868 goto out_unlock;
1869
1870 list_del_init(&user->list);
1871 user->remove(conn, user);
1872
1873out_unlock:
1874 hci_dev_unlock(hdev);
1875}
1876EXPORT_SYMBOL(l2cap_unregister_user);
1877
1878static void l2cap_unregister_all_users(struct l2cap_conn *conn)
1879{
1880 struct l2cap_user *user;
1881
1882 while (!list_empty(&conn->users)) {
1883 user = list_first_entry(&conn->users, struct l2cap_user, list);
1884 list_del_init(&user->list);
1885 user->remove(conn, user);
1886 }
1887}
1888
1889static void l2cap_conn_del(struct hci_conn *hcon, int err)
1890{
1891 struct l2cap_conn *conn = hcon->l2cap_data;
1892 struct l2cap_chan *chan, *l;
1893
1894 if (!conn)
1895 return;
1896
1897 BT_DBG("hcon %p conn %p, err %d", hcon, conn, err);
1898
1899 kfree_skb(conn->rx_skb);
1900
1901 skb_queue_purge(&conn->pending_rx);
1902
1903 /* We can not call flush_work(&conn->pending_rx_work) here since we
1904 * might block if we are running on a worker from the same workqueue
1905 * pending_rx_work is waiting on.
1906 */
1907 if (work_pending(&conn->pending_rx_work))
1908 cancel_work_sync(&conn->pending_rx_work);
1909
1910 cancel_delayed_work_sync(&conn->id_addr_timer);
1911
1912 l2cap_unregister_all_users(conn);
1913
1914 /* Force the connection to be immediately dropped */
1915 hcon->disc_timeout = 0;
1916
1917 mutex_lock(&conn->chan_lock);
1918
1919 /* Kill channels */
1920 list_for_each_entry_safe(chan, l, &conn->chan_l, list) {
1921 l2cap_chan_hold(chan);
1922 l2cap_chan_lock(chan);
1923
1924 l2cap_chan_del(chan, err);
1925
1926 chan->ops->close(chan);
1927
1928 l2cap_chan_unlock(chan);
1929 l2cap_chan_put(chan);
1930 }
1931
1932 mutex_unlock(&conn->chan_lock);
1933
1934 hci_chan_del(conn->hchan);
1935
1936 if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT)
1937 cancel_delayed_work_sync(&conn->info_timer);
1938
1939 hcon->l2cap_data = NULL;
1940 conn->hchan = NULL;
1941 l2cap_conn_put(conn);
1942}
1943
1944static void l2cap_conn_free(struct kref *ref)
1945{
1946 struct l2cap_conn *conn = container_of(ref, struct l2cap_conn, ref);
1947
1948 hci_conn_put(conn->hcon);
1949 kfree(conn);
1950}
1951
1952struct l2cap_conn *l2cap_conn_get(struct l2cap_conn *conn)
1953{
1954 kref_get(&conn->ref);
1955 return conn;
1956}
1957EXPORT_SYMBOL(l2cap_conn_get);
1958
1959void l2cap_conn_put(struct l2cap_conn *conn)
1960{
1961 kref_put(&conn->ref, l2cap_conn_free);
1962}
1963EXPORT_SYMBOL(l2cap_conn_put);
1964
1965/* ---- Socket interface ---- */
1966
1967/* Find socket with psm and source / destination bdaddr.
1968 * Returns closest match.
1969 */
1970static struct l2cap_chan *l2cap_global_chan_by_psm(int state, __le16 psm,
1971 bdaddr_t *src,
1972 bdaddr_t *dst,
1973 u8 link_type)
1974{
1975 struct l2cap_chan *c, *tmp, *c1 = NULL;
1976
1977 read_lock(&chan_list_lock);
1978
1979 list_for_each_entry_safe(c, tmp, &chan_list, global_l) {
1980 if (state && c->state != state)
1981 continue;
1982
1983 if (link_type == ACL_LINK && c->src_type != BDADDR_BREDR)
1984 continue;
1985
1986 if (link_type == LE_LINK && c->src_type == BDADDR_BREDR)
1987 continue;
1988
1989 if (c->chan_type != L2CAP_CHAN_FIXED && c->psm == psm) {
1990 int src_match, dst_match;
1991 int src_any, dst_any;
1992
1993 /* Exact match. */
1994 src_match = !bacmp(&c->src, src);
1995 dst_match = !bacmp(&c->dst, dst);
1996 if (src_match && dst_match) {
1997 if (!l2cap_chan_hold_unless_zero(c))
1998 continue;
1999
2000 read_unlock(&chan_list_lock);
2001 return c;
2002 }
2003
2004 /* Closest match */
2005 src_any = !bacmp(&c->src, BDADDR_ANY);
2006 dst_any = !bacmp(&c->dst, BDADDR_ANY);
2007 if ((src_match && dst_any) || (src_any && dst_match) ||
2008 (src_any && dst_any))
2009 c1 = c;
2010 }
2011 }
2012
2013 if (c1)
2014 c1 = l2cap_chan_hold_unless_zero(c1);
2015
2016 read_unlock(&chan_list_lock);
2017
2018 return c1;
2019}
2020
2021static void l2cap_monitor_timeout(struct work_struct *work)
2022{
2023 struct l2cap_chan *chan = container_of(work, struct l2cap_chan,
2024 monitor_timer.work);
2025
2026 BT_DBG("chan %p", chan);
2027
2028 l2cap_chan_lock(chan);
2029
2030 if (!chan->conn) {
2031 l2cap_chan_unlock(chan);
2032 l2cap_chan_put(chan);
2033 return;
2034 }
2035
2036 l2cap_tx(chan, NULL, NULL, L2CAP_EV_MONITOR_TO);
2037
2038 l2cap_chan_unlock(chan);
2039 l2cap_chan_put(chan);
2040}
2041
2042static void l2cap_retrans_timeout(struct work_struct *work)
2043{
2044 struct l2cap_chan *chan = container_of(work, struct l2cap_chan,
2045 retrans_timer.work);
2046
2047 BT_DBG("chan %p", chan);
2048
2049 l2cap_chan_lock(chan);
2050
2051 if (!chan->conn) {
2052 l2cap_chan_unlock(chan);
2053 l2cap_chan_put(chan);
2054 return;
2055 }
2056
2057 l2cap_tx(chan, NULL, NULL, L2CAP_EV_RETRANS_TO);
2058 l2cap_chan_unlock(chan);
2059 l2cap_chan_put(chan);
2060}
2061
2062static void l2cap_streaming_send(struct l2cap_chan *chan,
2063 struct sk_buff_head *skbs)
2064{
2065 struct sk_buff *skb;
2066 struct l2cap_ctrl *control;
2067
2068 BT_DBG("chan %p, skbs %p", chan, skbs);
2069
2070 if (__chan_is_moving(chan))
2071 return;
2072
2073 skb_queue_splice_tail_init(skbs, &chan->tx_q);
2074
2075 while (!skb_queue_empty(&chan->tx_q)) {
2076
2077 skb = skb_dequeue(&chan->tx_q);
2078
2079 bt_cb(skb)->l2cap.retries = 1;
2080 control = &bt_cb(skb)->l2cap;
2081
2082 control->reqseq = 0;
2083 control->txseq = chan->next_tx_seq;
2084
2085 __pack_control(chan, control, skb);
2086
2087 if (chan->fcs == L2CAP_FCS_CRC16) {
2088 u16 fcs = crc16(0, (u8 *) skb->data, skb->len);
2089 put_unaligned_le16(fcs, skb_put(skb, L2CAP_FCS_SIZE));
2090 }
2091
2092 l2cap_do_send(chan, skb);
2093
2094 BT_DBG("Sent txseq %u", control->txseq);
2095
2096 chan->next_tx_seq = __next_seq(chan, chan->next_tx_seq);
2097 chan->frames_sent++;
2098 }
2099}
2100
2101static int l2cap_ertm_send(struct l2cap_chan *chan)
2102{
2103 struct sk_buff *skb, *tx_skb;
2104 struct l2cap_ctrl *control;
2105 int sent = 0;
2106
2107 BT_DBG("chan %p", chan);
2108
2109 if (chan->state != BT_CONNECTED)
2110 return -ENOTCONN;
2111
2112 if (test_bit(CONN_REMOTE_BUSY, &chan->conn_state))
2113 return 0;
2114
2115 if (__chan_is_moving(chan))
2116 return 0;
2117
2118 while (chan->tx_send_head &&
2119 chan->unacked_frames < chan->remote_tx_win &&
2120 chan->tx_state == L2CAP_TX_STATE_XMIT) {
2121
2122 skb = chan->tx_send_head;
2123
2124 bt_cb(skb)->l2cap.retries = 1;
2125 control = &bt_cb(skb)->l2cap;
2126
2127 if (test_and_clear_bit(CONN_SEND_FBIT, &chan->conn_state))
2128 control->final = 1;
2129
2130 control->reqseq = chan->buffer_seq;
2131 chan->last_acked_seq = chan->buffer_seq;
2132 control->txseq = chan->next_tx_seq;
2133
2134 __pack_control(chan, control, skb);
2135
2136 if (chan->fcs == L2CAP_FCS_CRC16) {
2137 u16 fcs = crc16(0, (u8 *) skb->data, skb->len);
2138 put_unaligned_le16(fcs, skb_put(skb, L2CAP_FCS_SIZE));
2139 }
2140
2141 /* Clone after data has been modified. Data is assumed to be
2142 read-only (for locking purposes) on cloned sk_buffs.
2143 */
2144 tx_skb = skb_clone(skb, GFP_KERNEL);
2145
2146 if (!tx_skb)
2147 break;
2148
2149 __set_retrans_timer(chan);
2150
2151 chan->next_tx_seq = __next_seq(chan, chan->next_tx_seq);
2152 chan->unacked_frames++;
2153 chan->frames_sent++;
2154 sent++;
2155
2156 if (skb_queue_is_last(&chan->tx_q, skb))
2157 chan->tx_send_head = NULL;
2158 else
2159 chan->tx_send_head = skb_queue_next(&chan->tx_q, skb);
2160
2161 l2cap_do_send(chan, tx_skb);
2162 BT_DBG("Sent txseq %u", control->txseq);
2163 }
2164
2165 BT_DBG("Sent %d, %u unacked, %u in ERTM queue", sent,
2166 chan->unacked_frames, skb_queue_len(&chan->tx_q));
2167
2168 return sent;
2169}
2170
2171static void l2cap_ertm_resend(struct l2cap_chan *chan)
2172{
2173 struct l2cap_ctrl control;
2174 struct sk_buff *skb;
2175 struct sk_buff *tx_skb;
2176 u16 seq;
2177
2178 BT_DBG("chan %p", chan);
2179
2180 if (test_bit(CONN_REMOTE_BUSY, &chan->conn_state))
2181 return;
2182
2183 if (__chan_is_moving(chan))
2184 return;
2185
2186 while (chan->retrans_list.head != L2CAP_SEQ_LIST_CLEAR) {
2187 seq = l2cap_seq_list_pop(&chan->retrans_list);
2188
2189 skb = l2cap_ertm_seq_in_queue(&chan->tx_q, seq);
2190 if (!skb) {
2191 BT_DBG("Error: Can't retransmit seq %d, frame missing",
2192 seq);
2193 continue;
2194 }
2195
2196 bt_cb(skb)->l2cap.retries++;
2197 control = bt_cb(skb)->l2cap;
2198
2199 if (chan->max_tx != 0 &&
2200 bt_cb(skb)->l2cap.retries > chan->max_tx) {
2201 BT_DBG("Retry limit exceeded (%d)", chan->max_tx);
2202 l2cap_send_disconn_req(chan, ECONNRESET);
2203 l2cap_seq_list_clear(&chan->retrans_list);
2204 break;
2205 }
2206
2207 control.reqseq = chan->buffer_seq;
2208 if (test_and_clear_bit(CONN_SEND_FBIT, &chan->conn_state))
2209 control.final = 1;
2210 else
2211 control.final = 0;
2212
2213 if (skb_cloned(skb)) {
2214 /* Cloned sk_buffs are read-only, so we need a
2215 * writeable copy
2216 */
2217 tx_skb = skb_copy(skb, GFP_KERNEL);
2218 } else {
2219 tx_skb = skb_clone(skb, GFP_KERNEL);
2220 }
2221
2222 if (!tx_skb) {
2223 l2cap_seq_list_clear(&chan->retrans_list);
2224 break;
2225 }
2226
2227 /* Update skb contents */
2228 if (test_bit(FLAG_EXT_CTRL, &chan->flags)) {
2229 put_unaligned_le32(__pack_extended_control(&control),
2230 tx_skb->data + L2CAP_HDR_SIZE);
2231 } else {
2232 put_unaligned_le16(__pack_enhanced_control(&control),
2233 tx_skb->data + L2CAP_HDR_SIZE);
2234 }
2235
2236 /* Update FCS */
2237 if (chan->fcs == L2CAP_FCS_CRC16) {
2238 u16 fcs = crc16(0, (u8 *) tx_skb->data,
2239 tx_skb->len - L2CAP_FCS_SIZE);
2240 put_unaligned_le16(fcs, skb_tail_pointer(tx_skb) -
2241 L2CAP_FCS_SIZE);
2242 }
2243
2244 l2cap_do_send(chan, tx_skb);
2245
2246 BT_DBG("Resent txseq %d", control.txseq);
2247
2248 chan->last_acked_seq = chan->buffer_seq;
2249 }
2250}
2251
2252static void l2cap_retransmit(struct l2cap_chan *chan,
2253 struct l2cap_ctrl *control)
2254{
2255 BT_DBG("chan %p, control %p", chan, control);
2256
2257 l2cap_seq_list_append(&chan->retrans_list, control->reqseq);
2258 l2cap_ertm_resend(chan);
2259}
2260
2261static void l2cap_retransmit_all(struct l2cap_chan *chan,
2262 struct l2cap_ctrl *control)
2263{
2264 struct sk_buff *skb;
2265
2266 BT_DBG("chan %p, control %p", chan, control);
2267
2268 if (control->poll)
2269 set_bit(CONN_SEND_FBIT, &chan->conn_state);
2270
2271 l2cap_seq_list_clear(&chan->retrans_list);
2272
2273 if (test_bit(CONN_REMOTE_BUSY, &chan->conn_state))
2274 return;
2275
2276 if (chan->unacked_frames) {
2277 skb_queue_walk(&chan->tx_q, skb) {
2278 if (bt_cb(skb)->l2cap.txseq == control->reqseq ||
2279 skb == chan->tx_send_head)
2280 break;
2281 }
2282
2283 skb_queue_walk_from(&chan->tx_q, skb) {
2284 if (skb == chan->tx_send_head)
2285 break;
2286
2287 l2cap_seq_list_append(&chan->retrans_list,
2288 bt_cb(skb)->l2cap.txseq);
2289 }
2290
2291 l2cap_ertm_resend(chan);
2292 }
2293}
2294
2295static void l2cap_send_ack(struct l2cap_chan *chan)
2296{
2297 struct l2cap_ctrl control;
2298 u16 frames_to_ack = __seq_offset(chan, chan->buffer_seq,
2299 chan->last_acked_seq);
2300 int threshold;
2301
2302 BT_DBG("chan %p last_acked_seq %d buffer_seq %d",
2303 chan, chan->last_acked_seq, chan->buffer_seq);
2304
2305 memset(&control, 0, sizeof(control));
2306 control.sframe = 1;
2307
2308 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state) &&
2309 chan->rx_state == L2CAP_RX_STATE_RECV) {
2310 __clear_ack_timer(chan);
2311 control.super = L2CAP_SUPER_RNR;
2312 control.reqseq = chan->buffer_seq;
2313 l2cap_send_sframe(chan, &control);
2314 } else {
2315 if (!test_bit(CONN_REMOTE_BUSY, &chan->conn_state)) {
2316 l2cap_ertm_send(chan);
2317 /* If any i-frames were sent, they included an ack */
2318 if (chan->buffer_seq == chan->last_acked_seq)
2319 frames_to_ack = 0;
2320 }
2321
2322 /* Ack now if the window is 3/4ths full.
2323 * Calculate without mul or div
2324 */
2325 threshold = chan->ack_win;
2326 threshold += threshold << 1;
2327 threshold >>= 2;
2328
2329 BT_DBG("frames_to_ack %u, threshold %d", frames_to_ack,
2330 threshold);
2331
2332 if (frames_to_ack >= threshold) {
2333 __clear_ack_timer(chan);
2334 control.super = L2CAP_SUPER_RR;
2335 control.reqseq = chan->buffer_seq;
2336 l2cap_send_sframe(chan, &control);
2337 frames_to_ack = 0;
2338 }
2339
2340 if (frames_to_ack)
2341 __set_ack_timer(chan);
2342 }
2343}
2344
2345static inline int l2cap_skbuff_fromiovec(struct l2cap_chan *chan,
2346 struct msghdr *msg, int len,
2347 int count, struct sk_buff *skb)
2348{
2349 struct l2cap_conn *conn = chan->conn;
2350 struct sk_buff **frag;
2351 int sent = 0;
2352
2353 if (!copy_from_iter_full(skb_put(skb, count), count, &msg->msg_iter))
2354 return -EFAULT;
2355
2356 sent += count;
2357 len -= count;
2358
2359 /* Continuation fragments (no L2CAP header) */
2360 frag = &skb_shinfo(skb)->frag_list;
2361 while (len) {
2362 struct sk_buff *tmp;
2363
2364 count = min_t(unsigned int, conn->mtu, len);
2365
2366 tmp = chan->ops->alloc_skb(chan, 0, count,
2367 msg->msg_flags & MSG_DONTWAIT);
2368 if (IS_ERR(tmp))
2369 return PTR_ERR(tmp);
2370
2371 *frag = tmp;
2372
2373 if (!copy_from_iter_full(skb_put(*frag, count), count,
2374 &msg->msg_iter))
2375 return -EFAULT;
2376
2377 sent += count;
2378 len -= count;
2379
2380 skb->len += (*frag)->len;
2381 skb->data_len += (*frag)->len;
2382
2383 frag = &(*frag)->next;
2384 }
2385
2386 return sent;
2387}
2388
2389static struct sk_buff *l2cap_create_connless_pdu(struct l2cap_chan *chan,
2390 struct msghdr *msg, size_t len)
2391{
2392 struct l2cap_conn *conn = chan->conn;
2393 struct sk_buff *skb;
2394 int err, count, hlen = L2CAP_HDR_SIZE + L2CAP_PSMLEN_SIZE;
2395 struct l2cap_hdr *lh;
2396
2397 BT_DBG("chan %p psm 0x%2.2x len %zu", chan,
2398 __le16_to_cpu(chan->psm), len);
2399
2400 count = min_t(unsigned int, (conn->mtu - hlen), len);
2401
2402 skb = chan->ops->alloc_skb(chan, hlen, count,
2403 msg->msg_flags & MSG_DONTWAIT);
2404 if (IS_ERR(skb))
2405 return skb;
2406
2407 /* Create L2CAP header */
2408 lh = skb_put(skb, L2CAP_HDR_SIZE);
2409 lh->cid = cpu_to_le16(chan->dcid);
2410 lh->len = cpu_to_le16(len + L2CAP_PSMLEN_SIZE);
2411 put_unaligned(chan->psm, (__le16 *) skb_put(skb, L2CAP_PSMLEN_SIZE));
2412
2413 err = l2cap_skbuff_fromiovec(chan, msg, len, count, skb);
2414 if (unlikely(err < 0)) {
2415 kfree_skb(skb);
2416 return ERR_PTR(err);
2417 }
2418 return skb;
2419}
2420
2421static struct sk_buff *l2cap_create_basic_pdu(struct l2cap_chan *chan,
2422 struct msghdr *msg, size_t len)
2423{
2424 struct l2cap_conn *conn = chan->conn;
2425 struct sk_buff *skb;
2426 int err, count;
2427 struct l2cap_hdr *lh;
2428
2429 BT_DBG("chan %p len %zu", chan, len);
2430
2431 count = min_t(unsigned int, (conn->mtu - L2CAP_HDR_SIZE), len);
2432
2433 skb = chan->ops->alloc_skb(chan, L2CAP_HDR_SIZE, count,
2434 msg->msg_flags & MSG_DONTWAIT);
2435 if (IS_ERR(skb))
2436 return skb;
2437
2438 /* Create L2CAP header */
2439 lh = skb_put(skb, L2CAP_HDR_SIZE);
2440 lh->cid = cpu_to_le16(chan->dcid);
2441 lh->len = cpu_to_le16(len);
2442
2443 err = l2cap_skbuff_fromiovec(chan, msg, len, count, skb);
2444 if (unlikely(err < 0)) {
2445 kfree_skb(skb);
2446 return ERR_PTR(err);
2447 }
2448 return skb;
2449}
2450
2451static struct sk_buff *l2cap_create_iframe_pdu(struct l2cap_chan *chan,
2452 struct msghdr *msg, size_t len,
2453 u16 sdulen)
2454{
2455 struct l2cap_conn *conn = chan->conn;
2456 struct sk_buff *skb;
2457 int err, count, hlen;
2458 struct l2cap_hdr *lh;
2459
2460 BT_DBG("chan %p len %zu", chan, len);
2461
2462 if (!conn)
2463 return ERR_PTR(-ENOTCONN);
2464
2465 hlen = __ertm_hdr_size(chan);
2466
2467 if (sdulen)
2468 hlen += L2CAP_SDULEN_SIZE;
2469
2470 if (chan->fcs == L2CAP_FCS_CRC16)
2471 hlen += L2CAP_FCS_SIZE;
2472
2473 count = min_t(unsigned int, (conn->mtu - hlen), len);
2474
2475 skb = chan->ops->alloc_skb(chan, hlen, count,
2476 msg->msg_flags & MSG_DONTWAIT);
2477 if (IS_ERR(skb))
2478 return skb;
2479
2480 /* Create L2CAP header */
2481 lh = skb_put(skb, L2CAP_HDR_SIZE);
2482 lh->cid = cpu_to_le16(chan->dcid);
2483 lh->len = cpu_to_le16(len + (hlen - L2CAP_HDR_SIZE));
2484
2485 /* Control header is populated later */
2486 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
2487 put_unaligned_le32(0, skb_put(skb, L2CAP_EXT_CTRL_SIZE));
2488 else
2489 put_unaligned_le16(0, skb_put(skb, L2CAP_ENH_CTRL_SIZE));
2490
2491 if (sdulen)
2492 put_unaligned_le16(sdulen, skb_put(skb, L2CAP_SDULEN_SIZE));
2493
2494 err = l2cap_skbuff_fromiovec(chan, msg, len, count, skb);
2495 if (unlikely(err < 0)) {
2496 kfree_skb(skb);
2497 return ERR_PTR(err);
2498 }
2499
2500 bt_cb(skb)->l2cap.fcs = chan->fcs;
2501 bt_cb(skb)->l2cap.retries = 0;
2502 return skb;
2503}
2504
2505static int l2cap_segment_sdu(struct l2cap_chan *chan,
2506 struct sk_buff_head *seg_queue,
2507 struct msghdr *msg, size_t len)
2508{
2509 struct sk_buff *skb;
2510 u16 sdu_len;
2511 size_t pdu_len;
2512 u8 sar;
2513
2514 BT_DBG("chan %p, msg %p, len %zu", chan, msg, len);
2515
2516 /* It is critical that ERTM PDUs fit in a single HCI fragment,
2517 * so fragmented skbs are not used. The HCI layer's handling
2518 * of fragmented skbs is not compatible with ERTM's queueing.
2519 */
2520
2521 /* PDU size is derived from the HCI MTU */
2522 pdu_len = chan->conn->mtu;
2523
2524 /* Constrain PDU size for BR/EDR connections */
2525 if (!chan->hs_hcon)
2526 pdu_len = min_t(size_t, pdu_len, L2CAP_BREDR_MAX_PAYLOAD);
2527
2528 /* Adjust for largest possible L2CAP overhead. */
2529 if (chan->fcs)
2530 pdu_len -= L2CAP_FCS_SIZE;
2531
2532 pdu_len -= __ertm_hdr_size(chan);
2533
2534 /* Remote device may have requested smaller PDUs */
2535 pdu_len = min_t(size_t, pdu_len, chan->remote_mps);
2536
2537 if (len <= pdu_len) {
2538 sar = L2CAP_SAR_UNSEGMENTED;
2539 sdu_len = 0;
2540 pdu_len = len;
2541 } else {
2542 sar = L2CAP_SAR_START;
2543 sdu_len = len;
2544 }
2545
2546 while (len > 0) {
2547 skb = l2cap_create_iframe_pdu(chan, msg, pdu_len, sdu_len);
2548
2549 if (IS_ERR(skb)) {
2550 __skb_queue_purge(seg_queue);
2551 return PTR_ERR(skb);
2552 }
2553
2554 bt_cb(skb)->l2cap.sar = sar;
2555 __skb_queue_tail(seg_queue, skb);
2556
2557 len -= pdu_len;
2558 if (sdu_len)
2559 sdu_len = 0;
2560
2561 if (len <= pdu_len) {
2562 sar = L2CAP_SAR_END;
2563 pdu_len = len;
2564 } else {
2565 sar = L2CAP_SAR_CONTINUE;
2566 }
2567 }
2568
2569 return 0;
2570}
2571
2572static struct sk_buff *l2cap_create_le_flowctl_pdu(struct l2cap_chan *chan,
2573 struct msghdr *msg,
2574 size_t len, u16 sdulen)
2575{
2576 struct l2cap_conn *conn = chan->conn;
2577 struct sk_buff *skb;
2578 int err, count, hlen;
2579 struct l2cap_hdr *lh;
2580
2581 BT_DBG("chan %p len %zu", chan, len);
2582
2583 if (!conn)
2584 return ERR_PTR(-ENOTCONN);
2585
2586 hlen = L2CAP_HDR_SIZE;
2587
2588 if (sdulen)
2589 hlen += L2CAP_SDULEN_SIZE;
2590
2591 count = min_t(unsigned int, (conn->mtu - hlen), len);
2592
2593 skb = chan->ops->alloc_skb(chan, hlen, count,
2594 msg->msg_flags & MSG_DONTWAIT);
2595 if (IS_ERR(skb))
2596 return skb;
2597
2598 /* Create L2CAP header */
2599 lh = skb_put(skb, L2CAP_HDR_SIZE);
2600 lh->cid = cpu_to_le16(chan->dcid);
2601 lh->len = cpu_to_le16(len + (hlen - L2CAP_HDR_SIZE));
2602
2603 if (sdulen)
2604 put_unaligned_le16(sdulen, skb_put(skb, L2CAP_SDULEN_SIZE));
2605
2606 err = l2cap_skbuff_fromiovec(chan, msg, len, count, skb);
2607 if (unlikely(err < 0)) {
2608 kfree_skb(skb);
2609 return ERR_PTR(err);
2610 }
2611
2612 return skb;
2613}
2614
2615static int l2cap_segment_le_sdu(struct l2cap_chan *chan,
2616 struct sk_buff_head *seg_queue,
2617 struct msghdr *msg, size_t len)
2618{
2619 struct sk_buff *skb;
2620 size_t pdu_len;
2621 u16 sdu_len;
2622
2623 BT_DBG("chan %p, msg %p, len %zu", chan, msg, len);
2624
2625 sdu_len = len;
2626 pdu_len = chan->remote_mps - L2CAP_SDULEN_SIZE;
2627
2628 while (len > 0) {
2629 if (len <= pdu_len)
2630 pdu_len = len;
2631
2632 skb = l2cap_create_le_flowctl_pdu(chan, msg, pdu_len, sdu_len);
2633 if (IS_ERR(skb)) {
2634 __skb_queue_purge(seg_queue);
2635 return PTR_ERR(skb);
2636 }
2637
2638 __skb_queue_tail(seg_queue, skb);
2639
2640 len -= pdu_len;
2641
2642 if (sdu_len) {
2643 sdu_len = 0;
2644 pdu_len += L2CAP_SDULEN_SIZE;
2645 }
2646 }
2647
2648 return 0;
2649}
2650
2651static void l2cap_le_flowctl_send(struct l2cap_chan *chan)
2652{
2653 int sent = 0;
2654
2655 BT_DBG("chan %p", chan);
2656
2657 while (chan->tx_credits && !skb_queue_empty(&chan->tx_q)) {
2658 l2cap_do_send(chan, skb_dequeue(&chan->tx_q));
2659 chan->tx_credits--;
2660 sent++;
2661 }
2662
2663 BT_DBG("Sent %d credits %u queued %u", sent, chan->tx_credits,
2664 skb_queue_len(&chan->tx_q));
2665}
2666
2667int l2cap_chan_send(struct l2cap_chan *chan, struct msghdr *msg, size_t len)
2668{
2669 struct sk_buff *skb;
2670 int err;
2671 struct sk_buff_head seg_queue;
2672
2673 if (!chan->conn)
2674 return -ENOTCONN;
2675
2676 /* Connectionless channel */
2677 if (chan->chan_type == L2CAP_CHAN_CONN_LESS) {
2678 skb = l2cap_create_connless_pdu(chan, msg, len);
2679 if (IS_ERR(skb))
2680 return PTR_ERR(skb);
2681
2682 l2cap_do_send(chan, skb);
2683 return len;
2684 }
2685
2686 switch (chan->mode) {
2687 case L2CAP_MODE_LE_FLOWCTL:
2688 case L2CAP_MODE_EXT_FLOWCTL:
2689 /* Check outgoing MTU */
2690 if (len > chan->omtu)
2691 return -EMSGSIZE;
2692
2693 __skb_queue_head_init(&seg_queue);
2694
2695 err = l2cap_segment_le_sdu(chan, &seg_queue, msg, len);
2696
2697 if (chan->state != BT_CONNECTED) {
2698 __skb_queue_purge(&seg_queue);
2699 err = -ENOTCONN;
2700 }
2701
2702 if (err)
2703 return err;
2704
2705 skb_queue_splice_tail_init(&seg_queue, &chan->tx_q);
2706
2707 l2cap_le_flowctl_send(chan);
2708
2709 if (!chan->tx_credits)
2710 chan->ops->suspend(chan);
2711
2712 err = len;
2713
2714 break;
2715
2716 case L2CAP_MODE_BASIC:
2717 /* Check outgoing MTU */
2718 if (len > chan->omtu)
2719 return -EMSGSIZE;
2720
2721 /* Create a basic PDU */
2722 skb = l2cap_create_basic_pdu(chan, msg, len);
2723 if (IS_ERR(skb))
2724 return PTR_ERR(skb);
2725
2726 l2cap_do_send(chan, skb);
2727 err = len;
2728 break;
2729
2730 case L2CAP_MODE_ERTM:
2731 case L2CAP_MODE_STREAMING:
2732 /* Check outgoing MTU */
2733 if (len > chan->omtu) {
2734 err = -EMSGSIZE;
2735 break;
2736 }
2737
2738 __skb_queue_head_init(&seg_queue);
2739
2740 /* Do segmentation before calling in to the state machine,
2741 * since it's possible to block while waiting for memory
2742 * allocation.
2743 */
2744 err = l2cap_segment_sdu(chan, &seg_queue, msg, len);
2745
2746 if (err)
2747 break;
2748
2749 if (chan->mode == L2CAP_MODE_ERTM)
2750 l2cap_tx(chan, NULL, &seg_queue, L2CAP_EV_DATA_REQUEST);
2751 else
2752 l2cap_streaming_send(chan, &seg_queue);
2753
2754 err = len;
2755
2756 /* If the skbs were not queued for sending, they'll still be in
2757 * seg_queue and need to be purged.
2758 */
2759 __skb_queue_purge(&seg_queue);
2760 break;
2761
2762 default:
2763 BT_DBG("bad state %1.1x", chan->mode);
2764 err = -EBADFD;
2765 }
2766
2767 return err;
2768}
2769EXPORT_SYMBOL_GPL(l2cap_chan_send);
2770
2771static void l2cap_send_srej(struct l2cap_chan *chan, u16 txseq)
2772{
2773 struct l2cap_ctrl control;
2774 u16 seq;
2775
2776 BT_DBG("chan %p, txseq %u", chan, txseq);
2777
2778 memset(&control, 0, sizeof(control));
2779 control.sframe = 1;
2780 control.super = L2CAP_SUPER_SREJ;
2781
2782 for (seq = chan->expected_tx_seq; seq != txseq;
2783 seq = __next_seq(chan, seq)) {
2784 if (!l2cap_ertm_seq_in_queue(&chan->srej_q, seq)) {
2785 control.reqseq = seq;
2786 l2cap_send_sframe(chan, &control);
2787 l2cap_seq_list_append(&chan->srej_list, seq);
2788 }
2789 }
2790
2791 chan->expected_tx_seq = __next_seq(chan, txseq);
2792}
2793
2794static void l2cap_send_srej_tail(struct l2cap_chan *chan)
2795{
2796 struct l2cap_ctrl control;
2797
2798 BT_DBG("chan %p", chan);
2799
2800 if (chan->srej_list.tail == L2CAP_SEQ_LIST_CLEAR)
2801 return;
2802
2803 memset(&control, 0, sizeof(control));
2804 control.sframe = 1;
2805 control.super = L2CAP_SUPER_SREJ;
2806 control.reqseq = chan->srej_list.tail;
2807 l2cap_send_sframe(chan, &control);
2808}
2809
2810static void l2cap_send_srej_list(struct l2cap_chan *chan, u16 txseq)
2811{
2812 struct l2cap_ctrl control;
2813 u16 initial_head;
2814 u16 seq;
2815
2816 BT_DBG("chan %p, txseq %u", chan, txseq);
2817
2818 memset(&control, 0, sizeof(control));
2819 control.sframe = 1;
2820 control.super = L2CAP_SUPER_SREJ;
2821
2822 /* Capture initial list head to allow only one pass through the list. */
2823 initial_head = chan->srej_list.head;
2824
2825 do {
2826 seq = l2cap_seq_list_pop(&chan->srej_list);
2827 if (seq == txseq || seq == L2CAP_SEQ_LIST_CLEAR)
2828 break;
2829
2830 control.reqseq = seq;
2831 l2cap_send_sframe(chan, &control);
2832 l2cap_seq_list_append(&chan->srej_list, seq);
2833 } while (chan->srej_list.head != initial_head);
2834}
2835
2836static void l2cap_process_reqseq(struct l2cap_chan *chan, u16 reqseq)
2837{
2838 struct sk_buff *acked_skb;
2839 u16 ackseq;
2840
2841 BT_DBG("chan %p, reqseq %u", chan, reqseq);
2842
2843 if (chan->unacked_frames == 0 || reqseq == chan->expected_ack_seq)
2844 return;
2845
2846 BT_DBG("expected_ack_seq %u, unacked_frames %u",
2847 chan->expected_ack_seq, chan->unacked_frames);
2848
2849 for (ackseq = chan->expected_ack_seq; ackseq != reqseq;
2850 ackseq = __next_seq(chan, ackseq)) {
2851
2852 acked_skb = l2cap_ertm_seq_in_queue(&chan->tx_q, ackseq);
2853 if (acked_skb) {
2854 skb_unlink(acked_skb, &chan->tx_q);
2855 kfree_skb(acked_skb);
2856 chan->unacked_frames--;
2857 }
2858 }
2859
2860 chan->expected_ack_seq = reqseq;
2861
2862 if (chan->unacked_frames == 0)
2863 __clear_retrans_timer(chan);
2864
2865 BT_DBG("unacked_frames %u", chan->unacked_frames);
2866}
2867
2868static void l2cap_abort_rx_srej_sent(struct l2cap_chan *chan)
2869{
2870 BT_DBG("chan %p", chan);
2871
2872 chan->expected_tx_seq = chan->buffer_seq;
2873 l2cap_seq_list_clear(&chan->srej_list);
2874 skb_queue_purge(&chan->srej_q);
2875 chan->rx_state = L2CAP_RX_STATE_RECV;
2876}
2877
2878static void l2cap_tx_state_xmit(struct l2cap_chan *chan,
2879 struct l2cap_ctrl *control,
2880 struct sk_buff_head *skbs, u8 event)
2881{
2882 BT_DBG("chan %p, control %p, skbs %p, event %d", chan, control, skbs,
2883 event);
2884
2885 switch (event) {
2886 case L2CAP_EV_DATA_REQUEST:
2887 if (chan->tx_send_head == NULL)
2888 chan->tx_send_head = skb_peek(skbs);
2889
2890 skb_queue_splice_tail_init(skbs, &chan->tx_q);
2891 l2cap_ertm_send(chan);
2892 break;
2893 case L2CAP_EV_LOCAL_BUSY_DETECTED:
2894 BT_DBG("Enter LOCAL_BUSY");
2895 set_bit(CONN_LOCAL_BUSY, &chan->conn_state);
2896
2897 if (chan->rx_state == L2CAP_RX_STATE_SREJ_SENT) {
2898 /* The SREJ_SENT state must be aborted if we are to
2899 * enter the LOCAL_BUSY state.
2900 */
2901 l2cap_abort_rx_srej_sent(chan);
2902 }
2903
2904 l2cap_send_ack(chan);
2905
2906 break;
2907 case L2CAP_EV_LOCAL_BUSY_CLEAR:
2908 BT_DBG("Exit LOCAL_BUSY");
2909 clear_bit(CONN_LOCAL_BUSY, &chan->conn_state);
2910
2911 if (test_bit(CONN_RNR_SENT, &chan->conn_state)) {
2912 struct l2cap_ctrl local_control;
2913
2914 memset(&local_control, 0, sizeof(local_control));
2915 local_control.sframe = 1;
2916 local_control.super = L2CAP_SUPER_RR;
2917 local_control.poll = 1;
2918 local_control.reqseq = chan->buffer_seq;
2919 l2cap_send_sframe(chan, &local_control);
2920
2921 chan->retry_count = 1;
2922 __set_monitor_timer(chan);
2923 chan->tx_state = L2CAP_TX_STATE_WAIT_F;
2924 }
2925 break;
2926 case L2CAP_EV_RECV_REQSEQ_AND_FBIT:
2927 l2cap_process_reqseq(chan, control->reqseq);
2928 break;
2929 case L2CAP_EV_EXPLICIT_POLL:
2930 l2cap_send_rr_or_rnr(chan, 1);
2931 chan->retry_count = 1;
2932 __set_monitor_timer(chan);
2933 __clear_ack_timer(chan);
2934 chan->tx_state = L2CAP_TX_STATE_WAIT_F;
2935 break;
2936 case L2CAP_EV_RETRANS_TO:
2937 l2cap_send_rr_or_rnr(chan, 1);
2938 chan->retry_count = 1;
2939 __set_monitor_timer(chan);
2940 chan->tx_state = L2CAP_TX_STATE_WAIT_F;
2941 break;
2942 case L2CAP_EV_RECV_FBIT:
2943 /* Nothing to process */
2944 break;
2945 default:
2946 break;
2947 }
2948}
2949
2950static void l2cap_tx_state_wait_f(struct l2cap_chan *chan,
2951 struct l2cap_ctrl *control,
2952 struct sk_buff_head *skbs, u8 event)
2953{
2954 BT_DBG("chan %p, control %p, skbs %p, event %d", chan, control, skbs,
2955 event);
2956
2957 switch (event) {
2958 case L2CAP_EV_DATA_REQUEST:
2959 if (chan->tx_send_head == NULL)
2960 chan->tx_send_head = skb_peek(skbs);
2961 /* Queue data, but don't send. */
2962 skb_queue_splice_tail_init(skbs, &chan->tx_q);
2963 break;
2964 case L2CAP_EV_LOCAL_BUSY_DETECTED:
2965 BT_DBG("Enter LOCAL_BUSY");
2966 set_bit(CONN_LOCAL_BUSY, &chan->conn_state);
2967
2968 if (chan->rx_state == L2CAP_RX_STATE_SREJ_SENT) {
2969 /* The SREJ_SENT state must be aborted if we are to
2970 * enter the LOCAL_BUSY state.
2971 */
2972 l2cap_abort_rx_srej_sent(chan);
2973 }
2974
2975 l2cap_send_ack(chan);
2976
2977 break;
2978 case L2CAP_EV_LOCAL_BUSY_CLEAR:
2979 BT_DBG("Exit LOCAL_BUSY");
2980 clear_bit(CONN_LOCAL_BUSY, &chan->conn_state);
2981
2982 if (test_bit(CONN_RNR_SENT, &chan->conn_state)) {
2983 struct l2cap_ctrl local_control;
2984 memset(&local_control, 0, sizeof(local_control));
2985 local_control.sframe = 1;
2986 local_control.super = L2CAP_SUPER_RR;
2987 local_control.poll = 1;
2988 local_control.reqseq = chan->buffer_seq;
2989 l2cap_send_sframe(chan, &local_control);
2990
2991 chan->retry_count = 1;
2992 __set_monitor_timer(chan);
2993 chan->tx_state = L2CAP_TX_STATE_WAIT_F;
2994 }
2995 break;
2996 case L2CAP_EV_RECV_REQSEQ_AND_FBIT:
2997 l2cap_process_reqseq(chan, control->reqseq);
2998 fallthrough;
2999
3000 case L2CAP_EV_RECV_FBIT:
3001 if (control && control->final) {
3002 __clear_monitor_timer(chan);
3003 if (chan->unacked_frames > 0)
3004 __set_retrans_timer(chan);
3005 chan->retry_count = 0;
3006 chan->tx_state = L2CAP_TX_STATE_XMIT;
3007 BT_DBG("recv fbit tx_state 0x2.2%x", chan->tx_state);
3008 }
3009 break;
3010 case L2CAP_EV_EXPLICIT_POLL:
3011 /* Ignore */
3012 break;
3013 case L2CAP_EV_MONITOR_TO:
3014 if (chan->max_tx == 0 || chan->retry_count < chan->max_tx) {
3015 l2cap_send_rr_or_rnr(chan, 1);
3016 __set_monitor_timer(chan);
3017 chan->retry_count++;
3018 } else {
3019 l2cap_send_disconn_req(chan, ECONNABORTED);
3020 }
3021 break;
3022 default:
3023 break;
3024 }
3025}
3026
3027static void l2cap_tx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
3028 struct sk_buff_head *skbs, u8 event)
3029{
3030 BT_DBG("chan %p, control %p, skbs %p, event %d, state %d",
3031 chan, control, skbs, event, chan->tx_state);
3032
3033 switch (chan->tx_state) {
3034 case L2CAP_TX_STATE_XMIT:
3035 l2cap_tx_state_xmit(chan, control, skbs, event);
3036 break;
3037 case L2CAP_TX_STATE_WAIT_F:
3038 l2cap_tx_state_wait_f(chan, control, skbs, event);
3039 break;
3040 default:
3041 /* Ignore event */
3042 break;
3043 }
3044}
3045
3046static void l2cap_pass_to_tx(struct l2cap_chan *chan,
3047 struct l2cap_ctrl *control)
3048{
3049 BT_DBG("chan %p, control %p", chan, control);
3050 l2cap_tx(chan, control, NULL, L2CAP_EV_RECV_REQSEQ_AND_FBIT);
3051}
3052
3053static void l2cap_pass_to_tx_fbit(struct l2cap_chan *chan,
3054 struct l2cap_ctrl *control)
3055{
3056 BT_DBG("chan %p, control %p", chan, control);
3057 l2cap_tx(chan, control, NULL, L2CAP_EV_RECV_FBIT);
3058}
3059
3060/* Copy frame to all raw sockets on that connection */
3061static void l2cap_raw_recv(struct l2cap_conn *conn, struct sk_buff *skb)
3062{
3063 struct sk_buff *nskb;
3064 struct l2cap_chan *chan;
3065
3066 BT_DBG("conn %p", conn);
3067
3068 mutex_lock(&conn->chan_lock);
3069
3070 list_for_each_entry(chan, &conn->chan_l, list) {
3071 if (chan->chan_type != L2CAP_CHAN_RAW)
3072 continue;
3073
3074 /* Don't send frame to the channel it came from */
3075 if (bt_cb(skb)->l2cap.chan == chan)
3076 continue;
3077
3078 nskb = skb_clone(skb, GFP_KERNEL);
3079 if (!nskb)
3080 continue;
3081 if (chan->ops->recv(chan, nskb))
3082 kfree_skb(nskb);
3083 }
3084
3085 mutex_unlock(&conn->chan_lock);
3086}
3087
3088/* ---- L2CAP signalling commands ---- */
3089static struct sk_buff *l2cap_build_cmd(struct l2cap_conn *conn, u8 code,
3090 u8 ident, u16 dlen, void *data)
3091{
3092 struct sk_buff *skb, **frag;
3093 struct l2cap_cmd_hdr *cmd;
3094 struct l2cap_hdr *lh;
3095 int len, count;
3096
3097 BT_DBG("conn %p, code 0x%2.2x, ident 0x%2.2x, len %u",
3098 conn, code, ident, dlen);
3099
3100 if (conn->mtu < L2CAP_HDR_SIZE + L2CAP_CMD_HDR_SIZE)
3101 return NULL;
3102
3103 len = L2CAP_HDR_SIZE + L2CAP_CMD_HDR_SIZE + dlen;
3104 count = min_t(unsigned int, conn->mtu, len);
3105
3106 skb = bt_skb_alloc(count, GFP_KERNEL);
3107 if (!skb)
3108 return NULL;
3109
3110 lh = skb_put(skb, L2CAP_HDR_SIZE);
3111 lh->len = cpu_to_le16(L2CAP_CMD_HDR_SIZE + dlen);
3112
3113 if (conn->hcon->type == LE_LINK)
3114 lh->cid = cpu_to_le16(L2CAP_CID_LE_SIGNALING);
3115 else
3116 lh->cid = cpu_to_le16(L2CAP_CID_SIGNALING);
3117
3118 cmd = skb_put(skb, L2CAP_CMD_HDR_SIZE);
3119 cmd->code = code;
3120 cmd->ident = ident;
3121 cmd->len = cpu_to_le16(dlen);
3122
3123 if (dlen) {
3124 count -= L2CAP_HDR_SIZE + L2CAP_CMD_HDR_SIZE;
3125 skb_put_data(skb, data, count);
3126 data += count;
3127 }
3128
3129 len -= skb->len;
3130
3131 /* Continuation fragments (no L2CAP header) */
3132 frag = &skb_shinfo(skb)->frag_list;
3133 while (len) {
3134 count = min_t(unsigned int, conn->mtu, len);
3135
3136 *frag = bt_skb_alloc(count, GFP_KERNEL);
3137 if (!*frag)
3138 goto fail;
3139
3140 skb_put_data(*frag, data, count);
3141
3142 len -= count;
3143 data += count;
3144
3145 frag = &(*frag)->next;
3146 }
3147
3148 return skb;
3149
3150fail:
3151 kfree_skb(skb);
3152 return NULL;
3153}
3154
3155static inline int l2cap_get_conf_opt(void **ptr, int *type, int *olen,
3156 unsigned long *val)
3157{
3158 struct l2cap_conf_opt *opt = *ptr;
3159 int len;
3160
3161 len = L2CAP_CONF_OPT_SIZE + opt->len;
3162 *ptr += len;
3163
3164 *type = opt->type;
3165 *olen = opt->len;
3166
3167 switch (opt->len) {
3168 case 1:
3169 *val = *((u8 *) opt->val);
3170 break;
3171
3172 case 2:
3173 *val = get_unaligned_le16(opt->val);
3174 break;
3175
3176 case 4:
3177 *val = get_unaligned_le32(opt->val);
3178 break;
3179
3180 default:
3181 *val = (unsigned long) opt->val;
3182 break;
3183 }
3184
3185 BT_DBG("type 0x%2.2x len %u val 0x%lx", *type, opt->len, *val);
3186 return len;
3187}
3188
3189static void l2cap_add_conf_opt(void **ptr, u8 type, u8 len, unsigned long val, size_t size)
3190{
3191 struct l2cap_conf_opt *opt = *ptr;
3192
3193 BT_DBG("type 0x%2.2x len %u val 0x%lx", type, len, val);
3194
3195 if (size < L2CAP_CONF_OPT_SIZE + len)
3196 return;
3197
3198 opt->type = type;
3199 opt->len = len;
3200
3201 switch (len) {
3202 case 1:
3203 *((u8 *) opt->val) = val;
3204 break;
3205
3206 case 2:
3207 put_unaligned_le16(val, opt->val);
3208 break;
3209
3210 case 4:
3211 put_unaligned_le32(val, opt->val);
3212 break;
3213
3214 default:
3215 memcpy(opt->val, (void *) val, len);
3216 break;
3217 }
3218
3219 *ptr += L2CAP_CONF_OPT_SIZE + len;
3220}
3221
3222static void l2cap_add_opt_efs(void **ptr, struct l2cap_chan *chan, size_t size)
3223{
3224 struct l2cap_conf_efs efs;
3225
3226 switch (chan->mode) {
3227 case L2CAP_MODE_ERTM:
3228 efs.id = chan->local_id;
3229 efs.stype = chan->local_stype;
3230 efs.msdu = cpu_to_le16(chan->local_msdu);
3231 efs.sdu_itime = cpu_to_le32(chan->local_sdu_itime);
3232 efs.acc_lat = cpu_to_le32(L2CAP_DEFAULT_ACC_LAT);
3233 efs.flush_to = cpu_to_le32(L2CAP_EFS_DEFAULT_FLUSH_TO);
3234 break;
3235
3236 case L2CAP_MODE_STREAMING:
3237 efs.id = 1;
3238 efs.stype = L2CAP_SERV_BESTEFFORT;
3239 efs.msdu = cpu_to_le16(chan->local_msdu);
3240 efs.sdu_itime = cpu_to_le32(chan->local_sdu_itime);
3241 efs.acc_lat = 0;
3242 efs.flush_to = 0;
3243 break;
3244
3245 default:
3246 return;
3247 }
3248
3249 l2cap_add_conf_opt(ptr, L2CAP_CONF_EFS, sizeof(efs),
3250 (unsigned long) &efs, size);
3251}
3252
3253static void l2cap_ack_timeout(struct work_struct *work)
3254{
3255 struct l2cap_chan *chan = container_of(work, struct l2cap_chan,
3256 ack_timer.work);
3257 u16 frames_to_ack;
3258
3259 BT_DBG("chan %p", chan);
3260
3261 l2cap_chan_lock(chan);
3262
3263 frames_to_ack = __seq_offset(chan, chan->buffer_seq,
3264 chan->last_acked_seq);
3265
3266 if (frames_to_ack)
3267 l2cap_send_rr_or_rnr(chan, 0);
3268
3269 l2cap_chan_unlock(chan);
3270 l2cap_chan_put(chan);
3271}
3272
3273int l2cap_ertm_init(struct l2cap_chan *chan)
3274{
3275 int err;
3276
3277 chan->next_tx_seq = 0;
3278 chan->expected_tx_seq = 0;
3279 chan->expected_ack_seq = 0;
3280 chan->unacked_frames = 0;
3281 chan->buffer_seq = 0;
3282 chan->frames_sent = 0;
3283 chan->last_acked_seq = 0;
3284 chan->sdu = NULL;
3285 chan->sdu_last_frag = NULL;
3286 chan->sdu_len = 0;
3287
3288 skb_queue_head_init(&chan->tx_q);
3289
3290 chan->local_amp_id = AMP_ID_BREDR;
3291 chan->move_id = AMP_ID_BREDR;
3292 chan->move_state = L2CAP_MOVE_STABLE;
3293 chan->move_role = L2CAP_MOVE_ROLE_NONE;
3294
3295 if (chan->mode != L2CAP_MODE_ERTM)
3296 return 0;
3297
3298 chan->rx_state = L2CAP_RX_STATE_RECV;
3299 chan->tx_state = L2CAP_TX_STATE_XMIT;
3300
3301 skb_queue_head_init(&chan->srej_q);
3302
3303 err = l2cap_seq_list_init(&chan->srej_list, chan->tx_win);
3304 if (err < 0)
3305 return err;
3306
3307 err = l2cap_seq_list_init(&chan->retrans_list, chan->remote_tx_win);
3308 if (err < 0)
3309 l2cap_seq_list_free(&chan->srej_list);
3310
3311 return err;
3312}
3313
3314static inline __u8 l2cap_select_mode(__u8 mode, __u16 remote_feat_mask)
3315{
3316 switch (mode) {
3317 case L2CAP_MODE_STREAMING:
3318 case L2CAP_MODE_ERTM:
3319 if (l2cap_mode_supported(mode, remote_feat_mask))
3320 return mode;
3321 fallthrough;
3322 default:
3323 return L2CAP_MODE_BASIC;
3324 }
3325}
3326
3327static inline bool __l2cap_ews_supported(struct l2cap_conn *conn)
3328{
3329 return ((conn->local_fixed_chan & L2CAP_FC_A2MP) &&
3330 (conn->feat_mask & L2CAP_FEAT_EXT_WINDOW));
3331}
3332
3333static inline bool __l2cap_efs_supported(struct l2cap_conn *conn)
3334{
3335 return ((conn->local_fixed_chan & L2CAP_FC_A2MP) &&
3336 (conn->feat_mask & L2CAP_FEAT_EXT_FLOW));
3337}
3338
3339static void __l2cap_set_ertm_timeouts(struct l2cap_chan *chan,
3340 struct l2cap_conf_rfc *rfc)
3341{
3342 if (chan->local_amp_id != AMP_ID_BREDR && chan->hs_hcon) {
3343 u64 ertm_to = chan->hs_hcon->hdev->amp_be_flush_to;
3344
3345 /* Class 1 devices have must have ERTM timeouts
3346 * exceeding the Link Supervision Timeout. The
3347 * default Link Supervision Timeout for AMP
3348 * controllers is 10 seconds.
3349 *
3350 * Class 1 devices use 0xffffffff for their
3351 * best-effort flush timeout, so the clamping logic
3352 * will result in a timeout that meets the above
3353 * requirement. ERTM timeouts are 16-bit values, so
3354 * the maximum timeout is 65.535 seconds.
3355 */
3356
3357 /* Convert timeout to milliseconds and round */
3358 ertm_to = DIV_ROUND_UP_ULL(ertm_to, 1000);
3359
3360 /* This is the recommended formula for class 2 devices
3361 * that start ERTM timers when packets are sent to the
3362 * controller.
3363 */
3364 ertm_to = 3 * ertm_to + 500;
3365
3366 if (ertm_to > 0xffff)
3367 ertm_to = 0xffff;
3368
3369 rfc->retrans_timeout = cpu_to_le16((u16) ertm_to);
3370 rfc->monitor_timeout = rfc->retrans_timeout;
3371 } else {
3372 rfc->retrans_timeout = cpu_to_le16(L2CAP_DEFAULT_RETRANS_TO);
3373 rfc->monitor_timeout = cpu_to_le16(L2CAP_DEFAULT_MONITOR_TO);
3374 }
3375}
3376
3377static inline void l2cap_txwin_setup(struct l2cap_chan *chan)
3378{
3379 if (chan->tx_win > L2CAP_DEFAULT_TX_WINDOW &&
3380 __l2cap_ews_supported(chan->conn)) {
3381 /* use extended control field */
3382 set_bit(FLAG_EXT_CTRL, &chan->flags);
3383 chan->tx_win_max = L2CAP_DEFAULT_EXT_WINDOW;
3384 } else {
3385 chan->tx_win = min_t(u16, chan->tx_win,
3386 L2CAP_DEFAULT_TX_WINDOW);
3387 chan->tx_win_max = L2CAP_DEFAULT_TX_WINDOW;
3388 }
3389 chan->ack_win = chan->tx_win;
3390}
3391
3392static void l2cap_mtu_auto(struct l2cap_chan *chan)
3393{
3394 struct hci_conn *conn = chan->conn->hcon;
3395
3396 chan->imtu = L2CAP_DEFAULT_MIN_MTU;
3397
3398 /* The 2-DH1 packet has between 2 and 56 information bytes
3399 * (including the 2-byte payload header)
3400 */
3401 if (!(conn->pkt_type & HCI_2DH1))
3402 chan->imtu = 54;
3403
3404 /* The 3-DH1 packet has between 2 and 85 information bytes
3405 * (including the 2-byte payload header)
3406 */
3407 if (!(conn->pkt_type & HCI_3DH1))
3408 chan->imtu = 83;
3409
3410 /* The 2-DH3 packet has between 2 and 369 information bytes
3411 * (including the 2-byte payload header)
3412 */
3413 if (!(conn->pkt_type & HCI_2DH3))
3414 chan->imtu = 367;
3415
3416 /* The 3-DH3 packet has between 2 and 554 information bytes
3417 * (including the 2-byte payload header)
3418 */
3419 if (!(conn->pkt_type & HCI_3DH3))
3420 chan->imtu = 552;
3421
3422 /* The 2-DH5 packet has between 2 and 681 information bytes
3423 * (including the 2-byte payload header)
3424 */
3425 if (!(conn->pkt_type & HCI_2DH5))
3426 chan->imtu = 679;
3427
3428 /* The 3-DH5 packet has between 2 and 1023 information bytes
3429 * (including the 2-byte payload header)
3430 */
3431 if (!(conn->pkt_type & HCI_3DH5))
3432 chan->imtu = 1021;
3433}
3434
3435static int l2cap_build_conf_req(struct l2cap_chan *chan, void *data, size_t data_size)
3436{
3437 struct l2cap_conf_req *req = data;
3438 struct l2cap_conf_rfc rfc = { .mode = chan->mode };
3439 void *ptr = req->data;
3440 void *endptr = data + data_size;
3441 u16 size;
3442
3443 BT_DBG("chan %p", chan);
3444
3445 if (chan->num_conf_req || chan->num_conf_rsp)
3446 goto done;
3447
3448 switch (chan->mode) {
3449 case L2CAP_MODE_STREAMING:
3450 case L2CAP_MODE_ERTM:
3451 if (test_bit(CONF_STATE2_DEVICE, &chan->conf_state))
3452 break;
3453
3454 if (__l2cap_efs_supported(chan->conn))
3455 set_bit(FLAG_EFS_ENABLE, &chan->flags);
3456
3457 fallthrough;
3458 default:
3459 chan->mode = l2cap_select_mode(rfc.mode, chan->conn->feat_mask);
3460 break;
3461 }
3462
3463done:
3464 if (chan->imtu != L2CAP_DEFAULT_MTU) {
3465 if (!chan->imtu)
3466 l2cap_mtu_auto(chan);
3467 l2cap_add_conf_opt(&ptr, L2CAP_CONF_MTU, 2, chan->imtu,
3468 endptr - ptr);
3469 }
3470
3471 switch (chan->mode) {
3472 case L2CAP_MODE_BASIC:
3473 if (disable_ertm)
3474 break;
3475
3476 if (!(chan->conn->feat_mask & L2CAP_FEAT_ERTM) &&
3477 !(chan->conn->feat_mask & L2CAP_FEAT_STREAMING))
3478 break;
3479
3480 rfc.mode = L2CAP_MODE_BASIC;
3481 rfc.txwin_size = 0;
3482 rfc.max_transmit = 0;
3483 rfc.retrans_timeout = 0;
3484 rfc.monitor_timeout = 0;
3485 rfc.max_pdu_size = 0;
3486
3487 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3488 (unsigned long) &rfc, endptr - ptr);
3489 break;
3490
3491 case L2CAP_MODE_ERTM:
3492 rfc.mode = L2CAP_MODE_ERTM;
3493 rfc.max_transmit = chan->max_tx;
3494
3495 __l2cap_set_ertm_timeouts(chan, &rfc);
3496
3497 size = min_t(u16, L2CAP_DEFAULT_MAX_PDU_SIZE, chan->conn->mtu -
3498 L2CAP_EXT_HDR_SIZE - L2CAP_SDULEN_SIZE -
3499 L2CAP_FCS_SIZE);
3500 rfc.max_pdu_size = cpu_to_le16(size);
3501
3502 l2cap_txwin_setup(chan);
3503
3504 rfc.txwin_size = min_t(u16, chan->tx_win,
3505 L2CAP_DEFAULT_TX_WINDOW);
3506
3507 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3508 (unsigned long) &rfc, endptr - ptr);
3509
3510 if (test_bit(FLAG_EFS_ENABLE, &chan->flags))
3511 l2cap_add_opt_efs(&ptr, chan, endptr - ptr);
3512
3513 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
3514 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EWS, 2,
3515 chan->tx_win, endptr - ptr);
3516
3517 if (chan->conn->feat_mask & L2CAP_FEAT_FCS)
3518 if (chan->fcs == L2CAP_FCS_NONE ||
3519 test_bit(CONF_RECV_NO_FCS, &chan->conf_state)) {
3520 chan->fcs = L2CAP_FCS_NONE;
3521 l2cap_add_conf_opt(&ptr, L2CAP_CONF_FCS, 1,
3522 chan->fcs, endptr - ptr);
3523 }
3524 break;
3525
3526 case L2CAP_MODE_STREAMING:
3527 l2cap_txwin_setup(chan);
3528 rfc.mode = L2CAP_MODE_STREAMING;
3529 rfc.txwin_size = 0;
3530 rfc.max_transmit = 0;
3531 rfc.retrans_timeout = 0;
3532 rfc.monitor_timeout = 0;
3533
3534 size = min_t(u16, L2CAP_DEFAULT_MAX_PDU_SIZE, chan->conn->mtu -
3535 L2CAP_EXT_HDR_SIZE - L2CAP_SDULEN_SIZE -
3536 L2CAP_FCS_SIZE);
3537 rfc.max_pdu_size = cpu_to_le16(size);
3538
3539 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3540 (unsigned long) &rfc, endptr - ptr);
3541
3542 if (test_bit(FLAG_EFS_ENABLE, &chan->flags))
3543 l2cap_add_opt_efs(&ptr, chan, endptr - ptr);
3544
3545 if (chan->conn->feat_mask & L2CAP_FEAT_FCS)
3546 if (chan->fcs == L2CAP_FCS_NONE ||
3547 test_bit(CONF_RECV_NO_FCS, &chan->conf_state)) {
3548 chan->fcs = L2CAP_FCS_NONE;
3549 l2cap_add_conf_opt(&ptr, L2CAP_CONF_FCS, 1,
3550 chan->fcs, endptr - ptr);
3551 }
3552 break;
3553 }
3554
3555 req->dcid = cpu_to_le16(chan->dcid);
3556 req->flags = cpu_to_le16(0);
3557
3558 return ptr - data;
3559}
3560
3561static int l2cap_parse_conf_req(struct l2cap_chan *chan, void *data, size_t data_size)
3562{
3563 struct l2cap_conf_rsp *rsp = data;
3564 void *ptr = rsp->data;
3565 void *endptr = data + data_size;
3566 void *req = chan->conf_req;
3567 int len = chan->conf_len;
3568 int type, hint, olen;
3569 unsigned long val;
3570 struct l2cap_conf_rfc rfc = { .mode = L2CAP_MODE_BASIC };
3571 struct l2cap_conf_efs efs;
3572 u8 remote_efs = 0;
3573 u16 mtu = L2CAP_DEFAULT_MTU;
3574 u16 result = L2CAP_CONF_SUCCESS;
3575 u16 size;
3576
3577 BT_DBG("chan %p", chan);
3578
3579 while (len >= L2CAP_CONF_OPT_SIZE) {
3580 len -= l2cap_get_conf_opt(&req, &type, &olen, &val);
3581 if (len < 0)
3582 break;
3583
3584 hint = type & L2CAP_CONF_HINT;
3585 type &= L2CAP_CONF_MASK;
3586
3587 switch (type) {
3588 case L2CAP_CONF_MTU:
3589 if (olen != 2)
3590 break;
3591 mtu = val;
3592 break;
3593
3594 case L2CAP_CONF_FLUSH_TO:
3595 if (olen != 2)
3596 break;
3597 chan->flush_to = val;
3598 break;
3599
3600 case L2CAP_CONF_QOS:
3601 break;
3602
3603 case L2CAP_CONF_RFC:
3604 if (olen != sizeof(rfc))
3605 break;
3606 memcpy(&rfc, (void *) val, olen);
3607 break;
3608
3609 case L2CAP_CONF_FCS:
3610 if (olen != 1)
3611 break;
3612 if (val == L2CAP_FCS_NONE)
3613 set_bit(CONF_RECV_NO_FCS, &chan->conf_state);
3614 break;
3615
3616 case L2CAP_CONF_EFS:
3617 if (olen != sizeof(efs))
3618 break;
3619 remote_efs = 1;
3620 memcpy(&efs, (void *) val, olen);
3621 break;
3622
3623 case L2CAP_CONF_EWS:
3624 if (olen != 2)
3625 break;
3626 if (!(chan->conn->local_fixed_chan & L2CAP_FC_A2MP))
3627 return -ECONNREFUSED;
3628 set_bit(FLAG_EXT_CTRL, &chan->flags);
3629 set_bit(CONF_EWS_RECV, &chan->conf_state);
3630 chan->tx_win_max = L2CAP_DEFAULT_EXT_WINDOW;
3631 chan->remote_tx_win = val;
3632 break;
3633
3634 default:
3635 if (hint)
3636 break;
3637 result = L2CAP_CONF_UNKNOWN;
3638 l2cap_add_conf_opt(&ptr, (u8)type, sizeof(u8), type, endptr - ptr);
3639 break;
3640 }
3641 }
3642
3643 if (chan->num_conf_rsp || chan->num_conf_req > 1)
3644 goto done;
3645
3646 switch (chan->mode) {
3647 case L2CAP_MODE_STREAMING:
3648 case L2CAP_MODE_ERTM:
3649 if (!test_bit(CONF_STATE2_DEVICE, &chan->conf_state)) {
3650 chan->mode = l2cap_select_mode(rfc.mode,
3651 chan->conn->feat_mask);
3652 break;
3653 }
3654
3655 if (remote_efs) {
3656 if (__l2cap_efs_supported(chan->conn))
3657 set_bit(FLAG_EFS_ENABLE, &chan->flags);
3658 else
3659 return -ECONNREFUSED;
3660 }
3661
3662 if (chan->mode != rfc.mode)
3663 return -ECONNREFUSED;
3664
3665 break;
3666 }
3667
3668done:
3669 if (chan->mode != rfc.mode) {
3670 result = L2CAP_CONF_UNACCEPT;
3671 rfc.mode = chan->mode;
3672
3673 if (chan->num_conf_rsp == 1)
3674 return -ECONNREFUSED;
3675
3676 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3677 (unsigned long) &rfc, endptr - ptr);
3678 }
3679
3680 if (result == L2CAP_CONF_SUCCESS) {
3681 /* Configure output options and let the other side know
3682 * which ones we don't like. */
3683
3684 if (mtu < L2CAP_DEFAULT_MIN_MTU)
3685 result = L2CAP_CONF_UNACCEPT;
3686 else {
3687 chan->omtu = mtu;
3688 set_bit(CONF_MTU_DONE, &chan->conf_state);
3689 }
3690 l2cap_add_conf_opt(&ptr, L2CAP_CONF_MTU, 2, chan->omtu, endptr - ptr);
3691
3692 if (remote_efs) {
3693 if (chan->local_stype != L2CAP_SERV_NOTRAFIC &&
3694 efs.stype != L2CAP_SERV_NOTRAFIC &&
3695 efs.stype != chan->local_stype) {
3696
3697 result = L2CAP_CONF_UNACCEPT;
3698
3699 if (chan->num_conf_req >= 1)
3700 return -ECONNREFUSED;
3701
3702 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EFS,
3703 sizeof(efs),
3704 (unsigned long) &efs, endptr - ptr);
3705 } else {
3706 /* Send PENDING Conf Rsp */
3707 result = L2CAP_CONF_PENDING;
3708 set_bit(CONF_LOC_CONF_PEND, &chan->conf_state);
3709 }
3710 }
3711
3712 switch (rfc.mode) {
3713 case L2CAP_MODE_BASIC:
3714 chan->fcs = L2CAP_FCS_NONE;
3715 set_bit(CONF_MODE_DONE, &chan->conf_state);
3716 break;
3717
3718 case L2CAP_MODE_ERTM:
3719 if (!test_bit(CONF_EWS_RECV, &chan->conf_state))
3720 chan->remote_tx_win = rfc.txwin_size;
3721 else
3722 rfc.txwin_size = L2CAP_DEFAULT_TX_WINDOW;
3723
3724 chan->remote_max_tx = rfc.max_transmit;
3725
3726 size = min_t(u16, le16_to_cpu(rfc.max_pdu_size),
3727 chan->conn->mtu - L2CAP_EXT_HDR_SIZE -
3728 L2CAP_SDULEN_SIZE - L2CAP_FCS_SIZE);
3729 rfc.max_pdu_size = cpu_to_le16(size);
3730 chan->remote_mps = size;
3731
3732 __l2cap_set_ertm_timeouts(chan, &rfc);
3733
3734 set_bit(CONF_MODE_DONE, &chan->conf_state);
3735
3736 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC,
3737 sizeof(rfc), (unsigned long) &rfc, endptr - ptr);
3738
3739 if (remote_efs &&
3740 test_bit(FLAG_EFS_ENABLE, &chan->flags)) {
3741 chan->remote_id = efs.id;
3742 chan->remote_stype = efs.stype;
3743 chan->remote_msdu = le16_to_cpu(efs.msdu);
3744 chan->remote_flush_to =
3745 le32_to_cpu(efs.flush_to);
3746 chan->remote_acc_lat =
3747 le32_to_cpu(efs.acc_lat);
3748 chan->remote_sdu_itime =
3749 le32_to_cpu(efs.sdu_itime);
3750 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EFS,
3751 sizeof(efs),
3752 (unsigned long) &efs, endptr - ptr);
3753 }
3754 break;
3755
3756 case L2CAP_MODE_STREAMING:
3757 size = min_t(u16, le16_to_cpu(rfc.max_pdu_size),
3758 chan->conn->mtu - L2CAP_EXT_HDR_SIZE -
3759 L2CAP_SDULEN_SIZE - L2CAP_FCS_SIZE);
3760 rfc.max_pdu_size = cpu_to_le16(size);
3761 chan->remote_mps = size;
3762
3763 set_bit(CONF_MODE_DONE, &chan->conf_state);
3764
3765 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3766 (unsigned long) &rfc, endptr - ptr);
3767
3768 break;
3769
3770 default:
3771 result = L2CAP_CONF_UNACCEPT;
3772
3773 memset(&rfc, 0, sizeof(rfc));
3774 rfc.mode = chan->mode;
3775 }
3776
3777 if (result == L2CAP_CONF_SUCCESS)
3778 set_bit(CONF_OUTPUT_DONE, &chan->conf_state);
3779 }
3780 rsp->scid = cpu_to_le16(chan->dcid);
3781 rsp->result = cpu_to_le16(result);
3782 rsp->flags = cpu_to_le16(0);
3783
3784 return ptr - data;
3785}
3786
3787static int l2cap_parse_conf_rsp(struct l2cap_chan *chan, void *rsp, int len,
3788 void *data, size_t size, u16 *result)
3789{
3790 struct l2cap_conf_req *req = data;
3791 void *ptr = req->data;
3792 void *endptr = data + size;
3793 int type, olen;
3794 unsigned long val;
3795 struct l2cap_conf_rfc rfc = { .mode = L2CAP_MODE_BASIC };
3796 struct l2cap_conf_efs efs;
3797
3798 BT_DBG("chan %p, rsp %p, len %d, req %p", chan, rsp, len, data);
3799
3800 while (len >= L2CAP_CONF_OPT_SIZE) {
3801 len -= l2cap_get_conf_opt(&rsp, &type, &olen, &val);
3802 if (len < 0)
3803 break;
3804
3805 switch (type) {
3806 case L2CAP_CONF_MTU:
3807 if (olen != 2)
3808 break;
3809 if (val < L2CAP_DEFAULT_MIN_MTU) {
3810 *result = L2CAP_CONF_UNACCEPT;
3811 chan->imtu = L2CAP_DEFAULT_MIN_MTU;
3812 } else
3813 chan->imtu = val;
3814 l2cap_add_conf_opt(&ptr, L2CAP_CONF_MTU, 2, chan->imtu,
3815 endptr - ptr);
3816 break;
3817
3818 case L2CAP_CONF_FLUSH_TO:
3819 if (olen != 2)
3820 break;
3821 chan->flush_to = val;
3822 l2cap_add_conf_opt(&ptr, L2CAP_CONF_FLUSH_TO, 2,
3823 chan->flush_to, endptr - ptr);
3824 break;
3825
3826 case L2CAP_CONF_RFC:
3827 if (olen != sizeof(rfc))
3828 break;
3829 memcpy(&rfc, (void *)val, olen);
3830 if (test_bit(CONF_STATE2_DEVICE, &chan->conf_state) &&
3831 rfc.mode != chan->mode)
3832 return -ECONNREFUSED;
3833 chan->fcs = 0;
3834 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3835 (unsigned long) &rfc, endptr - ptr);
3836 break;
3837
3838 case L2CAP_CONF_EWS:
3839 if (olen != 2)
3840 break;
3841 chan->ack_win = min_t(u16, val, chan->ack_win);
3842 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EWS, 2,
3843 chan->tx_win, endptr - ptr);
3844 break;
3845
3846 case L2CAP_CONF_EFS:
3847 if (olen != sizeof(efs))
3848 break;
3849 memcpy(&efs, (void *)val, olen);
3850 if (chan->local_stype != L2CAP_SERV_NOTRAFIC &&
3851 efs.stype != L2CAP_SERV_NOTRAFIC &&
3852 efs.stype != chan->local_stype)
3853 return -ECONNREFUSED;
3854 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EFS, sizeof(efs),
3855 (unsigned long) &efs, endptr - ptr);
3856 break;
3857
3858 case L2CAP_CONF_FCS:
3859 if (olen != 1)
3860 break;
3861 if (*result == L2CAP_CONF_PENDING)
3862 if (val == L2CAP_FCS_NONE)
3863 set_bit(CONF_RECV_NO_FCS,
3864 &chan->conf_state);
3865 break;
3866 }
3867 }
3868
3869 if (chan->mode == L2CAP_MODE_BASIC && chan->mode != rfc.mode)
3870 return -ECONNREFUSED;
3871
3872 chan->mode = rfc.mode;
3873
3874 if (*result == L2CAP_CONF_SUCCESS || *result == L2CAP_CONF_PENDING) {
3875 switch (rfc.mode) {
3876 case L2CAP_MODE_ERTM:
3877 chan->retrans_timeout = le16_to_cpu(rfc.retrans_timeout);
3878 chan->monitor_timeout = le16_to_cpu(rfc.monitor_timeout);
3879 chan->mps = le16_to_cpu(rfc.max_pdu_size);
3880 if (!test_bit(FLAG_EXT_CTRL, &chan->flags))
3881 chan->ack_win = min_t(u16, chan->ack_win,
3882 rfc.txwin_size);
3883
3884 if (test_bit(FLAG_EFS_ENABLE, &chan->flags)) {
3885 chan->local_msdu = le16_to_cpu(efs.msdu);
3886 chan->local_sdu_itime =
3887 le32_to_cpu(efs.sdu_itime);
3888 chan->local_acc_lat = le32_to_cpu(efs.acc_lat);
3889 chan->local_flush_to =
3890 le32_to_cpu(efs.flush_to);
3891 }
3892 break;
3893
3894 case L2CAP_MODE_STREAMING:
3895 chan->mps = le16_to_cpu(rfc.max_pdu_size);
3896 }
3897 }
3898
3899 req->dcid = cpu_to_le16(chan->dcid);
3900 req->flags = cpu_to_le16(0);
3901
3902 return ptr - data;
3903}
3904
3905static int l2cap_build_conf_rsp(struct l2cap_chan *chan, void *data,
3906 u16 result, u16 flags)
3907{
3908 struct l2cap_conf_rsp *rsp = data;
3909 void *ptr = rsp->data;
3910
3911 BT_DBG("chan %p", chan);
3912
3913 rsp->scid = cpu_to_le16(chan->dcid);
3914 rsp->result = cpu_to_le16(result);
3915 rsp->flags = cpu_to_le16(flags);
3916
3917 return ptr - data;
3918}
3919
3920void __l2cap_le_connect_rsp_defer(struct l2cap_chan *chan)
3921{
3922 struct l2cap_le_conn_rsp rsp;
3923 struct l2cap_conn *conn = chan->conn;
3924
3925 BT_DBG("chan %p", chan);
3926
3927 rsp.dcid = cpu_to_le16(chan->scid);
3928 rsp.mtu = cpu_to_le16(chan->imtu);
3929 rsp.mps = cpu_to_le16(chan->mps);
3930 rsp.credits = cpu_to_le16(chan->rx_credits);
3931 rsp.result = cpu_to_le16(L2CAP_CR_LE_SUCCESS);
3932
3933 l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CONN_RSP, sizeof(rsp),
3934 &rsp);
3935}
3936
3937static void l2cap_ecred_list_defer(struct l2cap_chan *chan, void *data)
3938{
3939 int *result = data;
3940
3941 if (*result || test_bit(FLAG_ECRED_CONN_REQ_SENT, &chan->flags))
3942 return;
3943
3944 switch (chan->state) {
3945 case BT_CONNECT2:
3946 /* If channel still pending accept add to result */
3947 (*result)++;
3948 return;
3949 case BT_CONNECTED:
3950 return;
3951 default:
3952 /* If not connected or pending accept it has been refused */
3953 *result = -ECONNREFUSED;
3954 return;
3955 }
3956}
3957
3958struct l2cap_ecred_rsp_data {
3959 struct {
3960 struct l2cap_ecred_conn_rsp rsp;
3961 __le16 scid[L2CAP_ECRED_MAX_CID];
3962 } __packed pdu;
3963 int count;
3964};
3965
3966static void l2cap_ecred_rsp_defer(struct l2cap_chan *chan, void *data)
3967{
3968 struct l2cap_ecred_rsp_data *rsp = data;
3969
3970 if (test_bit(FLAG_ECRED_CONN_REQ_SENT, &chan->flags))
3971 return;
3972
3973 /* Reset ident so only one response is sent */
3974 chan->ident = 0;
3975
3976 /* Include all channels pending with the same ident */
3977 if (!rsp->pdu.rsp.result)
3978 rsp->pdu.rsp.dcid[rsp->count++] = cpu_to_le16(chan->scid);
3979 else
3980 l2cap_chan_del(chan, ECONNRESET);
3981}
3982
3983void __l2cap_ecred_conn_rsp_defer(struct l2cap_chan *chan)
3984{
3985 struct l2cap_conn *conn = chan->conn;
3986 struct l2cap_ecred_rsp_data data;
3987 u16 id = chan->ident;
3988 int result = 0;
3989
3990 if (!id)
3991 return;
3992
3993 BT_DBG("chan %p id %d", chan, id);
3994
3995 memset(&data, 0, sizeof(data));
3996
3997 data.pdu.rsp.mtu = cpu_to_le16(chan->imtu);
3998 data.pdu.rsp.mps = cpu_to_le16(chan->mps);
3999 data.pdu.rsp.credits = cpu_to_le16(chan->rx_credits);
4000 data.pdu.rsp.result = cpu_to_le16(L2CAP_CR_LE_SUCCESS);
4001
4002 /* Verify that all channels are ready */
4003 __l2cap_chan_list_id(conn, id, l2cap_ecred_list_defer, &result);
4004
4005 if (result > 0)
4006 return;
4007
4008 if (result < 0)
4009 data.pdu.rsp.result = cpu_to_le16(L2CAP_CR_LE_AUTHORIZATION);
4010
4011 /* Build response */
4012 __l2cap_chan_list_id(conn, id, l2cap_ecred_rsp_defer, &data);
4013
4014 l2cap_send_cmd(conn, id, L2CAP_ECRED_CONN_RSP,
4015 sizeof(data.pdu.rsp) + (data.count * sizeof(__le16)),
4016 &data.pdu);
4017}
4018
4019void __l2cap_connect_rsp_defer(struct l2cap_chan *chan)
4020{
4021 struct l2cap_conn_rsp rsp;
4022 struct l2cap_conn *conn = chan->conn;
4023 u8 buf[128];
4024 u8 rsp_code;
4025
4026 rsp.scid = cpu_to_le16(chan->dcid);
4027 rsp.dcid = cpu_to_le16(chan->scid);
4028 rsp.result = cpu_to_le16(L2CAP_CR_SUCCESS);
4029 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
4030
4031 if (chan->hs_hcon)
4032 rsp_code = L2CAP_CREATE_CHAN_RSP;
4033 else
4034 rsp_code = L2CAP_CONN_RSP;
4035
4036 BT_DBG("chan %p rsp_code %u", chan, rsp_code);
4037
4038 l2cap_send_cmd(conn, chan->ident, rsp_code, sizeof(rsp), &rsp);
4039
4040 if (test_and_set_bit(CONF_REQ_SENT, &chan->conf_state))
4041 return;
4042
4043 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
4044 l2cap_build_conf_req(chan, buf, sizeof(buf)), buf);
4045 chan->num_conf_req++;
4046}
4047
4048static void l2cap_conf_rfc_get(struct l2cap_chan *chan, void *rsp, int len)
4049{
4050 int type, olen;
4051 unsigned long val;
4052 /* Use sane default values in case a misbehaving remote device
4053 * did not send an RFC or extended window size option.
4054 */
4055 u16 txwin_ext = chan->ack_win;
4056 struct l2cap_conf_rfc rfc = {
4057 .mode = chan->mode,
4058 .retrans_timeout = cpu_to_le16(L2CAP_DEFAULT_RETRANS_TO),
4059 .monitor_timeout = cpu_to_le16(L2CAP_DEFAULT_MONITOR_TO),
4060 .max_pdu_size = cpu_to_le16(chan->imtu),
4061 .txwin_size = min_t(u16, chan->ack_win, L2CAP_DEFAULT_TX_WINDOW),
4062 };
4063
4064 BT_DBG("chan %p, rsp %p, len %d", chan, rsp, len);
4065
4066 if ((chan->mode != L2CAP_MODE_ERTM) && (chan->mode != L2CAP_MODE_STREAMING))
4067 return;
4068
4069 while (len >= L2CAP_CONF_OPT_SIZE) {
4070 len -= l2cap_get_conf_opt(&rsp, &type, &olen, &val);
4071 if (len < 0)
4072 break;
4073
4074 switch (type) {
4075 case L2CAP_CONF_RFC:
4076 if (olen != sizeof(rfc))
4077 break;
4078 memcpy(&rfc, (void *)val, olen);
4079 break;
4080 case L2CAP_CONF_EWS:
4081 if (olen != 2)
4082 break;
4083 txwin_ext = val;
4084 break;
4085 }
4086 }
4087
4088 switch (rfc.mode) {
4089 case L2CAP_MODE_ERTM:
4090 chan->retrans_timeout = le16_to_cpu(rfc.retrans_timeout);
4091 chan->monitor_timeout = le16_to_cpu(rfc.monitor_timeout);
4092 chan->mps = le16_to_cpu(rfc.max_pdu_size);
4093 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
4094 chan->ack_win = min_t(u16, chan->ack_win, txwin_ext);
4095 else
4096 chan->ack_win = min_t(u16, chan->ack_win,
4097 rfc.txwin_size);
4098 break;
4099 case L2CAP_MODE_STREAMING:
4100 chan->mps = le16_to_cpu(rfc.max_pdu_size);
4101 }
4102}
4103
4104static inline int l2cap_command_rej(struct l2cap_conn *conn,
4105 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4106 u8 *data)
4107{
4108 struct l2cap_cmd_rej_unk *rej = (struct l2cap_cmd_rej_unk *) data;
4109
4110 if (cmd_len < sizeof(*rej))
4111 return -EPROTO;
4112
4113 if (rej->reason != L2CAP_REJ_NOT_UNDERSTOOD)
4114 return 0;
4115
4116 if ((conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT) &&
4117 cmd->ident == conn->info_ident) {
4118 cancel_delayed_work(&conn->info_timer);
4119
4120 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
4121 conn->info_ident = 0;
4122
4123 l2cap_conn_start(conn);
4124 }
4125
4126 return 0;
4127}
4128
4129static struct l2cap_chan *l2cap_connect(struct l2cap_conn *conn,
4130 struct l2cap_cmd_hdr *cmd,
4131 u8 *data, u8 rsp_code, u8 amp_id)
4132{
4133 struct l2cap_conn_req *req = (struct l2cap_conn_req *) data;
4134 struct l2cap_conn_rsp rsp;
4135 struct l2cap_chan *chan = NULL, *pchan;
4136 int result, status = L2CAP_CS_NO_INFO;
4137
4138 u16 dcid = 0, scid = __le16_to_cpu(req->scid);
4139 __le16 psm = req->psm;
4140
4141 BT_DBG("psm 0x%2.2x scid 0x%4.4x", __le16_to_cpu(psm), scid);
4142
4143 /* Check if we have socket listening on psm */
4144 pchan = l2cap_global_chan_by_psm(BT_LISTEN, psm, &conn->hcon->src,
4145 &conn->hcon->dst, ACL_LINK);
4146 if (!pchan) {
4147 result = L2CAP_CR_BAD_PSM;
4148 goto sendresp;
4149 }
4150
4151 mutex_lock(&conn->chan_lock);
4152 l2cap_chan_lock(pchan);
4153
4154 /* Check if the ACL is secure enough (if not SDP) */
4155 if (psm != cpu_to_le16(L2CAP_PSM_SDP) &&
4156 !hci_conn_check_link_mode(conn->hcon)) {
4157 conn->disc_reason = HCI_ERROR_AUTH_FAILURE;
4158 result = L2CAP_CR_SEC_BLOCK;
4159 goto response;
4160 }
4161
4162 result = L2CAP_CR_NO_MEM;
4163
4164 /* Check for valid dynamic CID range (as per Erratum 3253) */
4165 if (scid < L2CAP_CID_DYN_START || scid > L2CAP_CID_DYN_END) {
4166 result = L2CAP_CR_INVALID_SCID;
4167 goto response;
4168 }
4169
4170 /* Check if we already have channel with that dcid */
4171 if (__l2cap_get_chan_by_dcid(conn, scid)) {
4172 result = L2CAP_CR_SCID_IN_USE;
4173 goto response;
4174 }
4175
4176 chan = pchan->ops->new_connection(pchan);
4177 if (!chan)
4178 goto response;
4179
4180 /* For certain devices (ex: HID mouse), support for authentication,
4181 * pairing and bonding is optional. For such devices, inorder to avoid
4182 * the ACL alive for too long after L2CAP disconnection, reset the ACL
4183 * disc_timeout back to HCI_DISCONN_TIMEOUT during L2CAP connect.
4184 */
4185 conn->hcon->disc_timeout = HCI_DISCONN_TIMEOUT;
4186
4187 bacpy(&chan->src, &conn->hcon->src);
4188 bacpy(&chan->dst, &conn->hcon->dst);
4189 chan->src_type = bdaddr_src_type(conn->hcon);
4190 chan->dst_type = bdaddr_dst_type(conn->hcon);
4191 chan->psm = psm;
4192 chan->dcid = scid;
4193 chan->local_amp_id = amp_id;
4194
4195 __l2cap_chan_add(conn, chan);
4196
4197 dcid = chan->scid;
4198
4199 __set_chan_timer(chan, chan->ops->get_sndtimeo(chan));
4200
4201 chan->ident = cmd->ident;
4202
4203 if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE) {
4204 if (l2cap_chan_check_security(chan, false)) {
4205 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) {
4206 l2cap_state_change(chan, BT_CONNECT2);
4207 result = L2CAP_CR_PEND;
4208 status = L2CAP_CS_AUTHOR_PEND;
4209 chan->ops->defer(chan);
4210 } else {
4211 /* Force pending result for AMP controllers.
4212 * The connection will succeed after the
4213 * physical link is up.
4214 */
4215 if (amp_id == AMP_ID_BREDR) {
4216 l2cap_state_change(chan, BT_CONFIG);
4217 result = L2CAP_CR_SUCCESS;
4218 } else {
4219 l2cap_state_change(chan, BT_CONNECT2);
4220 result = L2CAP_CR_PEND;
4221 }
4222 status = L2CAP_CS_NO_INFO;
4223 }
4224 } else {
4225 l2cap_state_change(chan, BT_CONNECT2);
4226 result = L2CAP_CR_PEND;
4227 status = L2CAP_CS_AUTHEN_PEND;
4228 }
4229 } else {
4230 l2cap_state_change(chan, BT_CONNECT2);
4231 result = L2CAP_CR_PEND;
4232 status = L2CAP_CS_NO_INFO;
4233 }
4234
4235response:
4236 l2cap_chan_unlock(pchan);
4237 mutex_unlock(&conn->chan_lock);
4238 l2cap_chan_put(pchan);
4239
4240sendresp:
4241 rsp.scid = cpu_to_le16(scid);
4242 rsp.dcid = cpu_to_le16(dcid);
4243 rsp.result = cpu_to_le16(result);
4244 rsp.status = cpu_to_le16(status);
4245 l2cap_send_cmd(conn, cmd->ident, rsp_code, sizeof(rsp), &rsp);
4246
4247 if (result == L2CAP_CR_PEND && status == L2CAP_CS_NO_INFO) {
4248 struct l2cap_info_req info;
4249 info.type = cpu_to_le16(L2CAP_IT_FEAT_MASK);
4250
4251 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_SENT;
4252 conn->info_ident = l2cap_get_ident(conn);
4253
4254 schedule_delayed_work(&conn->info_timer, L2CAP_INFO_TIMEOUT);
4255
4256 l2cap_send_cmd(conn, conn->info_ident, L2CAP_INFO_REQ,
4257 sizeof(info), &info);
4258 }
4259
4260 if (chan && !test_bit(CONF_REQ_SENT, &chan->conf_state) &&
4261 result == L2CAP_CR_SUCCESS) {
4262 u8 buf[128];
4263 set_bit(CONF_REQ_SENT, &chan->conf_state);
4264 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
4265 l2cap_build_conf_req(chan, buf, sizeof(buf)), buf);
4266 chan->num_conf_req++;
4267 }
4268
4269 return chan;
4270}
4271
4272static int l2cap_connect_req(struct l2cap_conn *conn,
4273 struct l2cap_cmd_hdr *cmd, u16 cmd_len, u8 *data)
4274{
4275 struct hci_dev *hdev = conn->hcon->hdev;
4276 struct hci_conn *hcon = conn->hcon;
4277
4278 if (cmd_len < sizeof(struct l2cap_conn_req))
4279 return -EPROTO;
4280
4281 hci_dev_lock(hdev);
4282 if (hci_dev_test_flag(hdev, HCI_MGMT) &&
4283 !test_and_set_bit(HCI_CONN_MGMT_CONNECTED, &hcon->flags))
4284 mgmt_device_connected(hdev, hcon, NULL, 0);
4285 hci_dev_unlock(hdev);
4286
4287 l2cap_connect(conn, cmd, data, L2CAP_CONN_RSP, 0);
4288 return 0;
4289}
4290
4291static int l2cap_connect_create_rsp(struct l2cap_conn *conn,
4292 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4293 u8 *data)
4294{
4295 struct l2cap_conn_rsp *rsp = (struct l2cap_conn_rsp *) data;
4296 u16 scid, dcid, result, status;
4297 struct l2cap_chan *chan;
4298 u8 req[128];
4299 int err;
4300
4301 if (cmd_len < sizeof(*rsp))
4302 return -EPROTO;
4303
4304 scid = __le16_to_cpu(rsp->scid);
4305 dcid = __le16_to_cpu(rsp->dcid);
4306 result = __le16_to_cpu(rsp->result);
4307 status = __le16_to_cpu(rsp->status);
4308
4309 if (result == L2CAP_CR_SUCCESS && (dcid < L2CAP_CID_DYN_START ||
4310 dcid > L2CAP_CID_DYN_END))
4311 return -EPROTO;
4312
4313 BT_DBG("dcid 0x%4.4x scid 0x%4.4x result 0x%2.2x status 0x%2.2x",
4314 dcid, scid, result, status);
4315
4316 mutex_lock(&conn->chan_lock);
4317
4318 if (scid) {
4319 chan = __l2cap_get_chan_by_scid(conn, scid);
4320 if (!chan) {
4321 err = -EBADSLT;
4322 goto unlock;
4323 }
4324 } else {
4325 chan = __l2cap_get_chan_by_ident(conn, cmd->ident);
4326 if (!chan) {
4327 err = -EBADSLT;
4328 goto unlock;
4329 }
4330 }
4331
4332 chan = l2cap_chan_hold_unless_zero(chan);
4333 if (!chan) {
4334 err = -EBADSLT;
4335 goto unlock;
4336 }
4337
4338 err = 0;
4339
4340 l2cap_chan_lock(chan);
4341
4342 switch (result) {
4343 case L2CAP_CR_SUCCESS:
4344 if (__l2cap_get_chan_by_dcid(conn, dcid)) {
4345 err = -EBADSLT;
4346 break;
4347 }
4348
4349 l2cap_state_change(chan, BT_CONFIG);
4350 chan->ident = 0;
4351 chan->dcid = dcid;
4352 clear_bit(CONF_CONNECT_PEND, &chan->conf_state);
4353
4354 if (test_and_set_bit(CONF_REQ_SENT, &chan->conf_state))
4355 break;
4356
4357 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
4358 l2cap_build_conf_req(chan, req, sizeof(req)), req);
4359 chan->num_conf_req++;
4360 break;
4361
4362 case L2CAP_CR_PEND:
4363 set_bit(CONF_CONNECT_PEND, &chan->conf_state);
4364 break;
4365
4366 default:
4367 l2cap_chan_del(chan, ECONNREFUSED);
4368 break;
4369 }
4370
4371 l2cap_chan_unlock(chan);
4372 l2cap_chan_put(chan);
4373
4374unlock:
4375 mutex_unlock(&conn->chan_lock);
4376
4377 return err;
4378}
4379
4380static inline void set_default_fcs(struct l2cap_chan *chan)
4381{
4382 /* FCS is enabled only in ERTM or streaming mode, if one or both
4383 * sides request it.
4384 */
4385 if (chan->mode != L2CAP_MODE_ERTM && chan->mode != L2CAP_MODE_STREAMING)
4386 chan->fcs = L2CAP_FCS_NONE;
4387 else if (!test_bit(CONF_RECV_NO_FCS, &chan->conf_state))
4388 chan->fcs = L2CAP_FCS_CRC16;
4389}
4390
4391static void l2cap_send_efs_conf_rsp(struct l2cap_chan *chan, void *data,
4392 u8 ident, u16 flags)
4393{
4394 struct l2cap_conn *conn = chan->conn;
4395
4396 BT_DBG("conn %p chan %p ident %d flags 0x%4.4x", conn, chan, ident,
4397 flags);
4398
4399 clear_bit(CONF_LOC_CONF_PEND, &chan->conf_state);
4400 set_bit(CONF_OUTPUT_DONE, &chan->conf_state);
4401
4402 l2cap_send_cmd(conn, ident, L2CAP_CONF_RSP,
4403 l2cap_build_conf_rsp(chan, data,
4404 L2CAP_CONF_SUCCESS, flags), data);
4405}
4406
4407static void cmd_reject_invalid_cid(struct l2cap_conn *conn, u8 ident,
4408 u16 scid, u16 dcid)
4409{
4410 struct l2cap_cmd_rej_cid rej;
4411
4412 rej.reason = cpu_to_le16(L2CAP_REJ_INVALID_CID);
4413 rej.scid = __cpu_to_le16(scid);
4414 rej.dcid = __cpu_to_le16(dcid);
4415
4416 l2cap_send_cmd(conn, ident, L2CAP_COMMAND_REJ, sizeof(rej), &rej);
4417}
4418
4419static inline int l2cap_config_req(struct l2cap_conn *conn,
4420 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4421 u8 *data)
4422{
4423 struct l2cap_conf_req *req = (struct l2cap_conf_req *) data;
4424 u16 dcid, flags;
4425 u8 rsp[64];
4426 struct l2cap_chan *chan;
4427 int len, err = 0;
4428
4429 if (cmd_len < sizeof(*req))
4430 return -EPROTO;
4431
4432 dcid = __le16_to_cpu(req->dcid);
4433 flags = __le16_to_cpu(req->flags);
4434
4435 BT_DBG("dcid 0x%4.4x flags 0x%2.2x", dcid, flags);
4436
4437 chan = l2cap_get_chan_by_scid(conn, dcid);
4438 if (!chan) {
4439 cmd_reject_invalid_cid(conn, cmd->ident, dcid, 0);
4440 return 0;
4441 }
4442
4443 if (chan->state != BT_CONFIG && chan->state != BT_CONNECT2 &&
4444 chan->state != BT_CONNECTED) {
4445 cmd_reject_invalid_cid(conn, cmd->ident, chan->scid,
4446 chan->dcid);
4447 goto unlock;
4448 }
4449
4450 /* Reject if config buffer is too small. */
4451 len = cmd_len - sizeof(*req);
4452 if (chan->conf_len + len > sizeof(chan->conf_req)) {
4453 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP,
4454 l2cap_build_conf_rsp(chan, rsp,
4455 L2CAP_CONF_REJECT, flags), rsp);
4456 goto unlock;
4457 }
4458
4459 /* Store config. */
4460 memcpy(chan->conf_req + chan->conf_len, req->data, len);
4461 chan->conf_len += len;
4462
4463 if (flags & L2CAP_CONF_FLAG_CONTINUATION) {
4464 /* Incomplete config. Send empty response. */
4465 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP,
4466 l2cap_build_conf_rsp(chan, rsp,
4467 L2CAP_CONF_SUCCESS, flags), rsp);
4468 goto unlock;
4469 }
4470
4471 /* Complete config. */
4472 len = l2cap_parse_conf_req(chan, rsp, sizeof(rsp));
4473 if (len < 0) {
4474 l2cap_send_disconn_req(chan, ECONNRESET);
4475 goto unlock;
4476 }
4477
4478 chan->ident = cmd->ident;
4479 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP, len, rsp);
4480 if (chan->num_conf_rsp < L2CAP_CONF_MAX_CONF_RSP)
4481 chan->num_conf_rsp++;
4482
4483 /* Reset config buffer. */
4484 chan->conf_len = 0;
4485
4486 if (!test_bit(CONF_OUTPUT_DONE, &chan->conf_state))
4487 goto unlock;
4488
4489 if (test_bit(CONF_INPUT_DONE, &chan->conf_state)) {
4490 set_default_fcs(chan);
4491
4492 if (chan->mode == L2CAP_MODE_ERTM ||
4493 chan->mode == L2CAP_MODE_STREAMING)
4494 err = l2cap_ertm_init(chan);
4495
4496 if (err < 0)
4497 l2cap_send_disconn_req(chan, -err);
4498 else
4499 l2cap_chan_ready(chan);
4500
4501 goto unlock;
4502 }
4503
4504 if (!test_and_set_bit(CONF_REQ_SENT, &chan->conf_state)) {
4505 u8 buf[64];
4506 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
4507 l2cap_build_conf_req(chan, buf, sizeof(buf)), buf);
4508 chan->num_conf_req++;
4509 }
4510
4511 /* Got Conf Rsp PENDING from remote side and assume we sent
4512 Conf Rsp PENDING in the code above */
4513 if (test_bit(CONF_REM_CONF_PEND, &chan->conf_state) &&
4514 test_bit(CONF_LOC_CONF_PEND, &chan->conf_state)) {
4515
4516 /* check compatibility */
4517
4518 /* Send rsp for BR/EDR channel */
4519 if (!chan->hs_hcon)
4520 l2cap_send_efs_conf_rsp(chan, rsp, cmd->ident, flags);
4521 else
4522 chan->ident = cmd->ident;
4523 }
4524
4525unlock:
4526 l2cap_chan_unlock(chan);
4527 l2cap_chan_put(chan);
4528 return err;
4529}
4530
4531static inline int l2cap_config_rsp(struct l2cap_conn *conn,
4532 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4533 u8 *data)
4534{
4535 struct l2cap_conf_rsp *rsp = (struct l2cap_conf_rsp *)data;
4536 u16 scid, flags, result;
4537 struct l2cap_chan *chan;
4538 int len = cmd_len - sizeof(*rsp);
4539 int err = 0;
4540
4541 if (cmd_len < sizeof(*rsp))
4542 return -EPROTO;
4543
4544 scid = __le16_to_cpu(rsp->scid);
4545 flags = __le16_to_cpu(rsp->flags);
4546 result = __le16_to_cpu(rsp->result);
4547
4548 BT_DBG("scid 0x%4.4x flags 0x%2.2x result 0x%2.2x len %d", scid, flags,
4549 result, len);
4550
4551 chan = l2cap_get_chan_by_scid(conn, scid);
4552 if (!chan)
4553 return 0;
4554
4555 switch (result) {
4556 case L2CAP_CONF_SUCCESS:
4557 l2cap_conf_rfc_get(chan, rsp->data, len);
4558 clear_bit(CONF_REM_CONF_PEND, &chan->conf_state);
4559 break;
4560
4561 case L2CAP_CONF_PENDING:
4562 set_bit(CONF_REM_CONF_PEND, &chan->conf_state);
4563
4564 if (test_bit(CONF_LOC_CONF_PEND, &chan->conf_state)) {
4565 char buf[64];
4566
4567 len = l2cap_parse_conf_rsp(chan, rsp->data, len,
4568 buf, sizeof(buf), &result);
4569 if (len < 0) {
4570 l2cap_send_disconn_req(chan, ECONNRESET);
4571 goto done;
4572 }
4573
4574 if (!chan->hs_hcon) {
4575 l2cap_send_efs_conf_rsp(chan, buf, cmd->ident,
4576 0);
4577 } else {
4578 if (l2cap_check_efs(chan)) {
4579 amp_create_logical_link(chan);
4580 chan->ident = cmd->ident;
4581 }
4582 }
4583 }
4584 goto done;
4585
4586 case L2CAP_CONF_UNKNOWN:
4587 case L2CAP_CONF_UNACCEPT:
4588 if (chan->num_conf_rsp <= L2CAP_CONF_MAX_CONF_RSP) {
4589 char req[64];
4590
4591 if (len > sizeof(req) - sizeof(struct l2cap_conf_req)) {
4592 l2cap_send_disconn_req(chan, ECONNRESET);
4593 goto done;
4594 }
4595
4596 /* throw out any old stored conf requests */
4597 result = L2CAP_CONF_SUCCESS;
4598 len = l2cap_parse_conf_rsp(chan, rsp->data, len,
4599 req, sizeof(req), &result);
4600 if (len < 0) {
4601 l2cap_send_disconn_req(chan, ECONNRESET);
4602 goto done;
4603 }
4604
4605 l2cap_send_cmd(conn, l2cap_get_ident(conn),
4606 L2CAP_CONF_REQ, len, req);
4607 chan->num_conf_req++;
4608 if (result != L2CAP_CONF_SUCCESS)
4609 goto done;
4610 break;
4611 }
4612 fallthrough;
4613
4614 default:
4615 l2cap_chan_set_err(chan, ECONNRESET);
4616
4617 __set_chan_timer(chan, L2CAP_DISC_REJ_TIMEOUT);
4618 l2cap_send_disconn_req(chan, ECONNRESET);
4619 goto done;
4620 }
4621
4622 if (flags & L2CAP_CONF_FLAG_CONTINUATION)
4623 goto done;
4624
4625 set_bit(CONF_INPUT_DONE, &chan->conf_state);
4626
4627 if (test_bit(CONF_OUTPUT_DONE, &chan->conf_state)) {
4628 set_default_fcs(chan);
4629
4630 if (chan->mode == L2CAP_MODE_ERTM ||
4631 chan->mode == L2CAP_MODE_STREAMING)
4632 err = l2cap_ertm_init(chan);
4633
4634 if (err < 0)
4635 l2cap_send_disconn_req(chan, -err);
4636 else
4637 l2cap_chan_ready(chan);
4638 }
4639
4640done:
4641 l2cap_chan_unlock(chan);
4642 l2cap_chan_put(chan);
4643 return err;
4644}
4645
4646static inline int l2cap_disconnect_req(struct l2cap_conn *conn,
4647 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4648 u8 *data)
4649{
4650 struct l2cap_disconn_req *req = (struct l2cap_disconn_req *) data;
4651 struct l2cap_disconn_rsp rsp;
4652 u16 dcid, scid;
4653 struct l2cap_chan *chan;
4654
4655 if (cmd_len != sizeof(*req))
4656 return -EPROTO;
4657
4658 scid = __le16_to_cpu(req->scid);
4659 dcid = __le16_to_cpu(req->dcid);
4660
4661 BT_DBG("scid 0x%4.4x dcid 0x%4.4x", scid, dcid);
4662
4663 chan = l2cap_get_chan_by_scid(conn, dcid);
4664 if (!chan) {
4665 cmd_reject_invalid_cid(conn, cmd->ident, dcid, scid);
4666 return 0;
4667 }
4668
4669 rsp.dcid = cpu_to_le16(chan->scid);
4670 rsp.scid = cpu_to_le16(chan->dcid);
4671 l2cap_send_cmd(conn, cmd->ident, L2CAP_DISCONN_RSP, sizeof(rsp), &rsp);
4672
4673 chan->ops->set_shutdown(chan);
4674
4675 l2cap_chan_unlock(chan);
4676 mutex_lock(&conn->chan_lock);
4677 l2cap_chan_lock(chan);
4678 l2cap_chan_del(chan, ECONNRESET);
4679 mutex_unlock(&conn->chan_lock);
4680
4681 chan->ops->close(chan);
4682
4683 l2cap_chan_unlock(chan);
4684 l2cap_chan_put(chan);
4685
4686 return 0;
4687}
4688
4689static inline int l2cap_disconnect_rsp(struct l2cap_conn *conn,
4690 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4691 u8 *data)
4692{
4693 struct l2cap_disconn_rsp *rsp = (struct l2cap_disconn_rsp *) data;
4694 u16 dcid, scid;
4695 struct l2cap_chan *chan;
4696
4697 if (cmd_len != sizeof(*rsp))
4698 return -EPROTO;
4699
4700 scid = __le16_to_cpu(rsp->scid);
4701 dcid = __le16_to_cpu(rsp->dcid);
4702
4703 BT_DBG("dcid 0x%4.4x scid 0x%4.4x", dcid, scid);
4704
4705 chan = l2cap_get_chan_by_scid(conn, scid);
4706 if (!chan) {
4707 return 0;
4708 }
4709
4710 if (chan->state != BT_DISCONN) {
4711 l2cap_chan_unlock(chan);
4712 l2cap_chan_put(chan);
4713 return 0;
4714 }
4715
4716 l2cap_chan_unlock(chan);
4717 mutex_lock(&conn->chan_lock);
4718 l2cap_chan_lock(chan);
4719 l2cap_chan_del(chan, 0);
4720 mutex_unlock(&conn->chan_lock);
4721
4722 chan->ops->close(chan);
4723
4724 l2cap_chan_unlock(chan);
4725 l2cap_chan_put(chan);
4726
4727 return 0;
4728}
4729
4730static inline int l2cap_information_req(struct l2cap_conn *conn,
4731 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4732 u8 *data)
4733{
4734 struct l2cap_info_req *req = (struct l2cap_info_req *) data;
4735 u16 type;
4736
4737 if (cmd_len != sizeof(*req))
4738 return -EPROTO;
4739
4740 type = __le16_to_cpu(req->type);
4741
4742 BT_DBG("type 0x%4.4x", type);
4743
4744 if (type == L2CAP_IT_FEAT_MASK) {
4745 u8 buf[8];
4746 u32 feat_mask = l2cap_feat_mask;
4747 struct l2cap_info_rsp *rsp = (struct l2cap_info_rsp *) buf;
4748 rsp->type = cpu_to_le16(L2CAP_IT_FEAT_MASK);
4749 rsp->result = cpu_to_le16(L2CAP_IR_SUCCESS);
4750 if (!disable_ertm)
4751 feat_mask |= L2CAP_FEAT_ERTM | L2CAP_FEAT_STREAMING
4752 | L2CAP_FEAT_FCS;
4753 if (conn->local_fixed_chan & L2CAP_FC_A2MP)
4754 feat_mask |= L2CAP_FEAT_EXT_FLOW
4755 | L2CAP_FEAT_EXT_WINDOW;
4756
4757 put_unaligned_le32(feat_mask, rsp->data);
4758 l2cap_send_cmd(conn, cmd->ident, L2CAP_INFO_RSP, sizeof(buf),
4759 buf);
4760 } else if (type == L2CAP_IT_FIXED_CHAN) {
4761 u8 buf[12];
4762 struct l2cap_info_rsp *rsp = (struct l2cap_info_rsp *) buf;
4763
4764 rsp->type = cpu_to_le16(L2CAP_IT_FIXED_CHAN);
4765 rsp->result = cpu_to_le16(L2CAP_IR_SUCCESS);
4766 rsp->data[0] = conn->local_fixed_chan;
4767 memset(rsp->data + 1, 0, 7);
4768 l2cap_send_cmd(conn, cmd->ident, L2CAP_INFO_RSP, sizeof(buf),
4769 buf);
4770 } else {
4771 struct l2cap_info_rsp rsp;
4772 rsp.type = cpu_to_le16(type);
4773 rsp.result = cpu_to_le16(L2CAP_IR_NOTSUPP);
4774 l2cap_send_cmd(conn, cmd->ident, L2CAP_INFO_RSP, sizeof(rsp),
4775 &rsp);
4776 }
4777
4778 return 0;
4779}
4780
4781static inline int l2cap_information_rsp(struct l2cap_conn *conn,
4782 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4783 u8 *data)
4784{
4785 struct l2cap_info_rsp *rsp = (struct l2cap_info_rsp *) data;
4786 u16 type, result;
4787
4788 if (cmd_len < sizeof(*rsp))
4789 return -EPROTO;
4790
4791 type = __le16_to_cpu(rsp->type);
4792 result = __le16_to_cpu(rsp->result);
4793
4794 BT_DBG("type 0x%4.4x result 0x%2.2x", type, result);
4795
4796 /* L2CAP Info req/rsp are unbound to channels, add extra checks */
4797 if (cmd->ident != conn->info_ident ||
4798 conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE)
4799 return 0;
4800
4801 cancel_delayed_work(&conn->info_timer);
4802
4803 if (result != L2CAP_IR_SUCCESS) {
4804 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
4805 conn->info_ident = 0;
4806
4807 l2cap_conn_start(conn);
4808
4809 return 0;
4810 }
4811
4812 switch (type) {
4813 case L2CAP_IT_FEAT_MASK:
4814 conn->feat_mask = get_unaligned_le32(rsp->data);
4815
4816 if (conn->feat_mask & L2CAP_FEAT_FIXED_CHAN) {
4817 struct l2cap_info_req req;
4818 req.type = cpu_to_le16(L2CAP_IT_FIXED_CHAN);
4819
4820 conn->info_ident = l2cap_get_ident(conn);
4821
4822 l2cap_send_cmd(conn, conn->info_ident,
4823 L2CAP_INFO_REQ, sizeof(req), &req);
4824 } else {
4825 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
4826 conn->info_ident = 0;
4827
4828 l2cap_conn_start(conn);
4829 }
4830 break;
4831
4832 case L2CAP_IT_FIXED_CHAN:
4833 conn->remote_fixed_chan = rsp->data[0];
4834 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
4835 conn->info_ident = 0;
4836
4837 l2cap_conn_start(conn);
4838 break;
4839 }
4840
4841 return 0;
4842}
4843
4844static int l2cap_create_channel_req(struct l2cap_conn *conn,
4845 struct l2cap_cmd_hdr *cmd,
4846 u16 cmd_len, void *data)
4847{
4848 struct l2cap_create_chan_req *req = data;
4849 struct l2cap_create_chan_rsp rsp;
4850 struct l2cap_chan *chan;
4851 struct hci_dev *hdev;
4852 u16 psm, scid;
4853
4854 if (cmd_len != sizeof(*req))
4855 return -EPROTO;
4856
4857 if (!(conn->local_fixed_chan & L2CAP_FC_A2MP))
4858 return -EINVAL;
4859
4860 psm = le16_to_cpu(req->psm);
4861 scid = le16_to_cpu(req->scid);
4862
4863 BT_DBG("psm 0x%2.2x, scid 0x%4.4x, amp_id %d", psm, scid, req->amp_id);
4864
4865 /* For controller id 0 make BR/EDR connection */
4866 if (req->amp_id == AMP_ID_BREDR) {
4867 l2cap_connect(conn, cmd, data, L2CAP_CREATE_CHAN_RSP,
4868 req->amp_id);
4869 return 0;
4870 }
4871
4872 /* Validate AMP controller id */
4873 hdev = hci_dev_get(req->amp_id);
4874 if (!hdev)
4875 goto error;
4876
4877 if (hdev->dev_type != HCI_AMP || !test_bit(HCI_UP, &hdev->flags)) {
4878 hci_dev_put(hdev);
4879 goto error;
4880 }
4881
4882 chan = l2cap_connect(conn, cmd, data, L2CAP_CREATE_CHAN_RSP,
4883 req->amp_id);
4884 if (chan) {
4885 struct amp_mgr *mgr = conn->hcon->amp_mgr;
4886 struct hci_conn *hs_hcon;
4887
4888 hs_hcon = hci_conn_hash_lookup_ba(hdev, AMP_LINK,
4889 &conn->hcon->dst);
4890 if (!hs_hcon) {
4891 hci_dev_put(hdev);
4892 cmd_reject_invalid_cid(conn, cmd->ident, chan->scid,
4893 chan->dcid);
4894 return 0;
4895 }
4896
4897 BT_DBG("mgr %p bredr_chan %p hs_hcon %p", mgr, chan, hs_hcon);
4898
4899 mgr->bredr_chan = chan;
4900 chan->hs_hcon = hs_hcon;
4901 chan->fcs = L2CAP_FCS_NONE;
4902 conn->mtu = hdev->block_mtu;
4903 }
4904
4905 hci_dev_put(hdev);
4906
4907 return 0;
4908
4909error:
4910 rsp.dcid = 0;
4911 rsp.scid = cpu_to_le16(scid);
4912 rsp.result = cpu_to_le16(L2CAP_CR_BAD_AMP);
4913 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
4914
4915 l2cap_send_cmd(conn, cmd->ident, L2CAP_CREATE_CHAN_RSP,
4916 sizeof(rsp), &rsp);
4917
4918 return 0;
4919}
4920
4921static void l2cap_send_move_chan_req(struct l2cap_chan *chan, u8 dest_amp_id)
4922{
4923 struct l2cap_move_chan_req req;
4924 u8 ident;
4925
4926 BT_DBG("chan %p, dest_amp_id %d", chan, dest_amp_id);
4927
4928 ident = l2cap_get_ident(chan->conn);
4929 chan->ident = ident;
4930
4931 req.icid = cpu_to_le16(chan->scid);
4932 req.dest_amp_id = dest_amp_id;
4933
4934 l2cap_send_cmd(chan->conn, ident, L2CAP_MOVE_CHAN_REQ, sizeof(req),
4935 &req);
4936
4937 __set_chan_timer(chan, L2CAP_MOVE_TIMEOUT);
4938}
4939
4940static void l2cap_send_move_chan_rsp(struct l2cap_chan *chan, u16 result)
4941{
4942 struct l2cap_move_chan_rsp rsp;
4943
4944 BT_DBG("chan %p, result 0x%4.4x", chan, result);
4945
4946 rsp.icid = cpu_to_le16(chan->dcid);
4947 rsp.result = cpu_to_le16(result);
4948
4949 l2cap_send_cmd(chan->conn, chan->ident, L2CAP_MOVE_CHAN_RSP,
4950 sizeof(rsp), &rsp);
4951}
4952
4953static void l2cap_send_move_chan_cfm(struct l2cap_chan *chan, u16 result)
4954{
4955 struct l2cap_move_chan_cfm cfm;
4956
4957 BT_DBG("chan %p, result 0x%4.4x", chan, result);
4958
4959 chan->ident = l2cap_get_ident(chan->conn);
4960
4961 cfm.icid = cpu_to_le16(chan->scid);
4962 cfm.result = cpu_to_le16(result);
4963
4964 l2cap_send_cmd(chan->conn, chan->ident, L2CAP_MOVE_CHAN_CFM,
4965 sizeof(cfm), &cfm);
4966
4967 __set_chan_timer(chan, L2CAP_MOVE_TIMEOUT);
4968}
4969
4970static void l2cap_send_move_chan_cfm_icid(struct l2cap_conn *conn, u16 icid)
4971{
4972 struct l2cap_move_chan_cfm cfm;
4973
4974 BT_DBG("conn %p, icid 0x%4.4x", conn, icid);
4975
4976 cfm.icid = cpu_to_le16(icid);
4977 cfm.result = cpu_to_le16(L2CAP_MC_UNCONFIRMED);
4978
4979 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_MOVE_CHAN_CFM,
4980 sizeof(cfm), &cfm);
4981}
4982
4983static void l2cap_send_move_chan_cfm_rsp(struct l2cap_conn *conn, u8 ident,
4984 u16 icid)
4985{
4986 struct l2cap_move_chan_cfm_rsp rsp;
4987
4988 BT_DBG("icid 0x%4.4x", icid);
4989
4990 rsp.icid = cpu_to_le16(icid);
4991 l2cap_send_cmd(conn, ident, L2CAP_MOVE_CHAN_CFM_RSP, sizeof(rsp), &rsp);
4992}
4993
4994static void __release_logical_link(struct l2cap_chan *chan)
4995{
4996 chan->hs_hchan = NULL;
4997 chan->hs_hcon = NULL;
4998
4999 /* Placeholder - release the logical link */
5000}
5001
5002static void l2cap_logical_fail(struct l2cap_chan *chan)
5003{
5004 /* Logical link setup failed */
5005 if (chan->state != BT_CONNECTED) {
5006 /* Create channel failure, disconnect */
5007 l2cap_send_disconn_req(chan, ECONNRESET);
5008 return;
5009 }
5010
5011 switch (chan->move_role) {
5012 case L2CAP_MOVE_ROLE_RESPONDER:
5013 l2cap_move_done(chan);
5014 l2cap_send_move_chan_rsp(chan, L2CAP_MR_NOT_SUPP);
5015 break;
5016 case L2CAP_MOVE_ROLE_INITIATOR:
5017 if (chan->move_state == L2CAP_MOVE_WAIT_LOGICAL_COMP ||
5018 chan->move_state == L2CAP_MOVE_WAIT_LOGICAL_CFM) {
5019 /* Remote has only sent pending or
5020 * success responses, clean up
5021 */
5022 l2cap_move_done(chan);
5023 }
5024
5025 /* Other amp move states imply that the move
5026 * has already aborted
5027 */
5028 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
5029 break;
5030 }
5031}
5032
5033static void l2cap_logical_finish_create(struct l2cap_chan *chan,
5034 struct hci_chan *hchan)
5035{
5036 struct l2cap_conf_rsp rsp;
5037
5038 chan->hs_hchan = hchan;
5039 chan->hs_hcon->l2cap_data = chan->conn;
5040
5041 l2cap_send_efs_conf_rsp(chan, &rsp, chan->ident, 0);
5042
5043 if (test_bit(CONF_INPUT_DONE, &chan->conf_state)) {
5044 int err;
5045
5046 set_default_fcs(chan);
5047
5048 err = l2cap_ertm_init(chan);
5049 if (err < 0)
5050 l2cap_send_disconn_req(chan, -err);
5051 else
5052 l2cap_chan_ready(chan);
5053 }
5054}
5055
5056static void l2cap_logical_finish_move(struct l2cap_chan *chan,
5057 struct hci_chan *hchan)
5058{
5059 chan->hs_hcon = hchan->conn;
5060 chan->hs_hcon->l2cap_data = chan->conn;
5061
5062 BT_DBG("move_state %d", chan->move_state);
5063
5064 switch (chan->move_state) {
5065 case L2CAP_MOVE_WAIT_LOGICAL_COMP:
5066 /* Move confirm will be sent after a success
5067 * response is received
5068 */
5069 chan->move_state = L2CAP_MOVE_WAIT_RSP_SUCCESS;
5070 break;
5071 case L2CAP_MOVE_WAIT_LOGICAL_CFM:
5072 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
5073 chan->move_state = L2CAP_MOVE_WAIT_LOCAL_BUSY;
5074 } else if (chan->move_role == L2CAP_MOVE_ROLE_INITIATOR) {
5075 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM_RSP;
5076 l2cap_send_move_chan_cfm(chan, L2CAP_MC_CONFIRMED);
5077 } else if (chan->move_role == L2CAP_MOVE_ROLE_RESPONDER) {
5078 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM;
5079 l2cap_send_move_chan_rsp(chan, L2CAP_MR_SUCCESS);
5080 }
5081 break;
5082 default:
5083 /* Move was not in expected state, free the channel */
5084 __release_logical_link(chan);
5085
5086 chan->move_state = L2CAP_MOVE_STABLE;
5087 }
5088}
5089
5090/* Call with chan locked */
5091void l2cap_logical_cfm(struct l2cap_chan *chan, struct hci_chan *hchan,
5092 u8 status)
5093{
5094 BT_DBG("chan %p, hchan %p, status %d", chan, hchan, status);
5095
5096 if (status) {
5097 l2cap_logical_fail(chan);
5098 __release_logical_link(chan);
5099 return;
5100 }
5101
5102 if (chan->state != BT_CONNECTED) {
5103 /* Ignore logical link if channel is on BR/EDR */
5104 if (chan->local_amp_id != AMP_ID_BREDR)
5105 l2cap_logical_finish_create(chan, hchan);
5106 } else {
5107 l2cap_logical_finish_move(chan, hchan);
5108 }
5109}
5110
5111void l2cap_move_start(struct l2cap_chan *chan)
5112{
5113 BT_DBG("chan %p", chan);
5114
5115 if (chan->local_amp_id == AMP_ID_BREDR) {
5116 if (chan->chan_policy != BT_CHANNEL_POLICY_AMP_PREFERRED)
5117 return;
5118 chan->move_role = L2CAP_MOVE_ROLE_INITIATOR;
5119 chan->move_state = L2CAP_MOVE_WAIT_PREPARE;
5120 /* Placeholder - start physical link setup */
5121 } else {
5122 chan->move_role = L2CAP_MOVE_ROLE_INITIATOR;
5123 chan->move_state = L2CAP_MOVE_WAIT_RSP_SUCCESS;
5124 chan->move_id = 0;
5125 l2cap_move_setup(chan);
5126 l2cap_send_move_chan_req(chan, 0);
5127 }
5128}
5129
5130static void l2cap_do_create(struct l2cap_chan *chan, int result,
5131 u8 local_amp_id, u8 remote_amp_id)
5132{
5133 BT_DBG("chan %p state %s %u -> %u", chan, state_to_string(chan->state),
5134 local_amp_id, remote_amp_id);
5135
5136 chan->fcs = L2CAP_FCS_NONE;
5137
5138 /* Outgoing channel on AMP */
5139 if (chan->state == BT_CONNECT) {
5140 if (result == L2CAP_CR_SUCCESS) {
5141 chan->local_amp_id = local_amp_id;
5142 l2cap_send_create_chan_req(chan, remote_amp_id);
5143 } else {
5144 /* Revert to BR/EDR connect */
5145 l2cap_send_conn_req(chan);
5146 }
5147
5148 return;
5149 }
5150
5151 /* Incoming channel on AMP */
5152 if (__l2cap_no_conn_pending(chan)) {
5153 struct l2cap_conn_rsp rsp;
5154 char buf[128];
5155 rsp.scid = cpu_to_le16(chan->dcid);
5156 rsp.dcid = cpu_to_le16(chan->scid);
5157
5158 if (result == L2CAP_CR_SUCCESS) {
5159 /* Send successful response */
5160 rsp.result = cpu_to_le16(L2CAP_CR_SUCCESS);
5161 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
5162 } else {
5163 /* Send negative response */
5164 rsp.result = cpu_to_le16(L2CAP_CR_NO_MEM);
5165 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
5166 }
5167
5168 l2cap_send_cmd(chan->conn, chan->ident, L2CAP_CREATE_CHAN_RSP,
5169 sizeof(rsp), &rsp);
5170
5171 if (result == L2CAP_CR_SUCCESS) {
5172 l2cap_state_change(chan, BT_CONFIG);
5173 set_bit(CONF_REQ_SENT, &chan->conf_state);
5174 l2cap_send_cmd(chan->conn, l2cap_get_ident(chan->conn),
5175 L2CAP_CONF_REQ,
5176 l2cap_build_conf_req(chan, buf, sizeof(buf)), buf);
5177 chan->num_conf_req++;
5178 }
5179 }
5180}
5181
5182static void l2cap_do_move_initiate(struct l2cap_chan *chan, u8 local_amp_id,
5183 u8 remote_amp_id)
5184{
5185 l2cap_move_setup(chan);
5186 chan->move_id = local_amp_id;
5187 chan->move_state = L2CAP_MOVE_WAIT_RSP;
5188
5189 l2cap_send_move_chan_req(chan, remote_amp_id);
5190}
5191
5192static void l2cap_do_move_respond(struct l2cap_chan *chan, int result)
5193{
5194 struct hci_chan *hchan = NULL;
5195
5196 /* Placeholder - get hci_chan for logical link */
5197
5198 if (hchan) {
5199 if (hchan->state == BT_CONNECTED) {
5200 /* Logical link is ready to go */
5201 chan->hs_hcon = hchan->conn;
5202 chan->hs_hcon->l2cap_data = chan->conn;
5203 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM;
5204 l2cap_send_move_chan_rsp(chan, L2CAP_MR_SUCCESS);
5205
5206 l2cap_logical_cfm(chan, hchan, L2CAP_MR_SUCCESS);
5207 } else {
5208 /* Wait for logical link to be ready */
5209 chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_CFM;
5210 }
5211 } else {
5212 /* Logical link not available */
5213 l2cap_send_move_chan_rsp(chan, L2CAP_MR_NOT_ALLOWED);
5214 }
5215}
5216
5217static void l2cap_do_move_cancel(struct l2cap_chan *chan, int result)
5218{
5219 if (chan->move_role == L2CAP_MOVE_ROLE_RESPONDER) {
5220 u8 rsp_result;
5221 if (result == -EINVAL)
5222 rsp_result = L2CAP_MR_BAD_ID;
5223 else
5224 rsp_result = L2CAP_MR_NOT_ALLOWED;
5225
5226 l2cap_send_move_chan_rsp(chan, rsp_result);
5227 }
5228
5229 chan->move_role = L2CAP_MOVE_ROLE_NONE;
5230 chan->move_state = L2CAP_MOVE_STABLE;
5231
5232 /* Restart data transmission */
5233 l2cap_ertm_send(chan);
5234}
5235
5236/* Invoke with locked chan */
5237void __l2cap_physical_cfm(struct l2cap_chan *chan, int result)
5238{
5239 u8 local_amp_id = chan->local_amp_id;
5240 u8 remote_amp_id = chan->remote_amp_id;
5241
5242 BT_DBG("chan %p, result %d, local_amp_id %d, remote_amp_id %d",
5243 chan, result, local_amp_id, remote_amp_id);
5244
5245 if (chan->state == BT_DISCONN || chan->state == BT_CLOSED)
5246 return;
5247
5248 if (chan->state != BT_CONNECTED) {
5249 l2cap_do_create(chan, result, local_amp_id, remote_amp_id);
5250 } else if (result != L2CAP_MR_SUCCESS) {
5251 l2cap_do_move_cancel(chan, result);
5252 } else {
5253 switch (chan->move_role) {
5254 case L2CAP_MOVE_ROLE_INITIATOR:
5255 l2cap_do_move_initiate(chan, local_amp_id,
5256 remote_amp_id);
5257 break;
5258 case L2CAP_MOVE_ROLE_RESPONDER:
5259 l2cap_do_move_respond(chan, result);
5260 break;
5261 default:
5262 l2cap_do_move_cancel(chan, result);
5263 break;
5264 }
5265 }
5266}
5267
5268static inline int l2cap_move_channel_req(struct l2cap_conn *conn,
5269 struct l2cap_cmd_hdr *cmd,
5270 u16 cmd_len, void *data)
5271{
5272 struct l2cap_move_chan_req *req = data;
5273 struct l2cap_move_chan_rsp rsp;
5274 struct l2cap_chan *chan;
5275 u16 icid = 0;
5276 u16 result = L2CAP_MR_NOT_ALLOWED;
5277
5278 if (cmd_len != sizeof(*req))
5279 return -EPROTO;
5280
5281 icid = le16_to_cpu(req->icid);
5282
5283 BT_DBG("icid 0x%4.4x, dest_amp_id %d", icid, req->dest_amp_id);
5284
5285 if (!(conn->local_fixed_chan & L2CAP_FC_A2MP))
5286 return -EINVAL;
5287
5288 chan = l2cap_get_chan_by_dcid(conn, icid);
5289 if (!chan) {
5290 rsp.icid = cpu_to_le16(icid);
5291 rsp.result = cpu_to_le16(L2CAP_MR_NOT_ALLOWED);
5292 l2cap_send_cmd(conn, cmd->ident, L2CAP_MOVE_CHAN_RSP,
5293 sizeof(rsp), &rsp);
5294 return 0;
5295 }
5296
5297 chan->ident = cmd->ident;
5298
5299 if (chan->scid < L2CAP_CID_DYN_START ||
5300 chan->chan_policy == BT_CHANNEL_POLICY_BREDR_ONLY ||
5301 (chan->mode != L2CAP_MODE_ERTM &&
5302 chan->mode != L2CAP_MODE_STREAMING)) {
5303 result = L2CAP_MR_NOT_ALLOWED;
5304 goto send_move_response;
5305 }
5306
5307 if (chan->local_amp_id == req->dest_amp_id) {
5308 result = L2CAP_MR_SAME_ID;
5309 goto send_move_response;
5310 }
5311
5312 if (req->dest_amp_id != AMP_ID_BREDR) {
5313 struct hci_dev *hdev;
5314 hdev = hci_dev_get(req->dest_amp_id);
5315 if (!hdev || hdev->dev_type != HCI_AMP ||
5316 !test_bit(HCI_UP, &hdev->flags)) {
5317 if (hdev)
5318 hci_dev_put(hdev);
5319
5320 result = L2CAP_MR_BAD_ID;
5321 goto send_move_response;
5322 }
5323 hci_dev_put(hdev);
5324 }
5325
5326 /* Detect a move collision. Only send a collision response
5327 * if this side has "lost", otherwise proceed with the move.
5328 * The winner has the larger bd_addr.
5329 */
5330 if ((__chan_is_moving(chan) ||
5331 chan->move_role != L2CAP_MOVE_ROLE_NONE) &&
5332 bacmp(&conn->hcon->src, &conn->hcon->dst) > 0) {
5333 result = L2CAP_MR_COLLISION;
5334 goto send_move_response;
5335 }
5336
5337 chan->move_role = L2CAP_MOVE_ROLE_RESPONDER;
5338 l2cap_move_setup(chan);
5339 chan->move_id = req->dest_amp_id;
5340
5341 if (req->dest_amp_id == AMP_ID_BREDR) {
5342 /* Moving to BR/EDR */
5343 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
5344 chan->move_state = L2CAP_MOVE_WAIT_LOCAL_BUSY;
5345 result = L2CAP_MR_PEND;
5346 } else {
5347 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM;
5348 result = L2CAP_MR_SUCCESS;
5349 }
5350 } else {
5351 chan->move_state = L2CAP_MOVE_WAIT_PREPARE;
5352 /* Placeholder - uncomment when amp functions are available */
5353 /*amp_accept_physical(chan, req->dest_amp_id);*/
5354 result = L2CAP_MR_PEND;
5355 }
5356
5357send_move_response:
5358 l2cap_send_move_chan_rsp(chan, result);
5359
5360 l2cap_chan_unlock(chan);
5361 l2cap_chan_put(chan);
5362
5363 return 0;
5364}
5365
5366static void l2cap_move_continue(struct l2cap_conn *conn, u16 icid, u16 result)
5367{
5368 struct l2cap_chan *chan;
5369 struct hci_chan *hchan = NULL;
5370
5371 chan = l2cap_get_chan_by_scid(conn, icid);
5372 if (!chan) {
5373 l2cap_send_move_chan_cfm_icid(conn, icid);
5374 return;
5375 }
5376
5377 __clear_chan_timer(chan);
5378 if (result == L2CAP_MR_PEND)
5379 __set_chan_timer(chan, L2CAP_MOVE_ERTX_TIMEOUT);
5380
5381 switch (chan->move_state) {
5382 case L2CAP_MOVE_WAIT_LOGICAL_COMP:
5383 /* Move confirm will be sent when logical link
5384 * is complete.
5385 */
5386 chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_CFM;
5387 break;
5388 case L2CAP_MOVE_WAIT_RSP_SUCCESS:
5389 if (result == L2CAP_MR_PEND) {
5390 break;
5391 } else if (test_bit(CONN_LOCAL_BUSY,
5392 &chan->conn_state)) {
5393 chan->move_state = L2CAP_MOVE_WAIT_LOCAL_BUSY;
5394 } else {
5395 /* Logical link is up or moving to BR/EDR,
5396 * proceed with move
5397 */
5398 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM_RSP;
5399 l2cap_send_move_chan_cfm(chan, L2CAP_MC_CONFIRMED);
5400 }
5401 break;
5402 case L2CAP_MOVE_WAIT_RSP:
5403 /* Moving to AMP */
5404 if (result == L2CAP_MR_SUCCESS) {
5405 /* Remote is ready, send confirm immediately
5406 * after logical link is ready
5407 */
5408 chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_CFM;
5409 } else {
5410 /* Both logical link and move success
5411 * are required to confirm
5412 */
5413 chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_COMP;
5414 }
5415
5416 /* Placeholder - get hci_chan for logical link */
5417 if (!hchan) {
5418 /* Logical link not available */
5419 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
5420 break;
5421 }
5422
5423 /* If the logical link is not yet connected, do not
5424 * send confirmation.
5425 */
5426 if (hchan->state != BT_CONNECTED)
5427 break;
5428
5429 /* Logical link is already ready to go */
5430
5431 chan->hs_hcon = hchan->conn;
5432 chan->hs_hcon->l2cap_data = chan->conn;
5433
5434 if (result == L2CAP_MR_SUCCESS) {
5435 /* Can confirm now */
5436 l2cap_send_move_chan_cfm(chan, L2CAP_MC_CONFIRMED);
5437 } else {
5438 /* Now only need move success
5439 * to confirm
5440 */
5441 chan->move_state = L2CAP_MOVE_WAIT_RSP_SUCCESS;
5442 }
5443
5444 l2cap_logical_cfm(chan, hchan, L2CAP_MR_SUCCESS);
5445 break;
5446 default:
5447 /* Any other amp move state means the move failed. */
5448 chan->move_id = chan->local_amp_id;
5449 l2cap_move_done(chan);
5450 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
5451 }
5452
5453 l2cap_chan_unlock(chan);
5454 l2cap_chan_put(chan);
5455}
5456
5457static void l2cap_move_fail(struct l2cap_conn *conn, u8 ident, u16 icid,
5458 u16 result)
5459{
5460 struct l2cap_chan *chan;
5461
5462 chan = l2cap_get_chan_by_ident(conn, ident);
5463 if (!chan) {
5464 /* Could not locate channel, icid is best guess */
5465 l2cap_send_move_chan_cfm_icid(conn, icid);
5466 return;
5467 }
5468
5469 __clear_chan_timer(chan);
5470
5471 if (chan->move_role == L2CAP_MOVE_ROLE_INITIATOR) {
5472 if (result == L2CAP_MR_COLLISION) {
5473 chan->move_role = L2CAP_MOVE_ROLE_RESPONDER;
5474 } else {
5475 /* Cleanup - cancel move */
5476 chan->move_id = chan->local_amp_id;
5477 l2cap_move_done(chan);
5478 }
5479 }
5480
5481 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
5482
5483 l2cap_chan_unlock(chan);
5484 l2cap_chan_put(chan);
5485}
5486
5487static int l2cap_move_channel_rsp(struct l2cap_conn *conn,
5488 struct l2cap_cmd_hdr *cmd,
5489 u16 cmd_len, void *data)
5490{
5491 struct l2cap_move_chan_rsp *rsp = data;
5492 u16 icid, result;
5493
5494 if (cmd_len != sizeof(*rsp))
5495 return -EPROTO;
5496
5497 icid = le16_to_cpu(rsp->icid);
5498 result = le16_to_cpu(rsp->result);
5499
5500 BT_DBG("icid 0x%4.4x, result 0x%4.4x", icid, result);
5501
5502 if (result == L2CAP_MR_SUCCESS || result == L2CAP_MR_PEND)
5503 l2cap_move_continue(conn, icid, result);
5504 else
5505 l2cap_move_fail(conn, cmd->ident, icid, result);
5506
5507 return 0;
5508}
5509
5510static int l2cap_move_channel_confirm(struct l2cap_conn *conn,
5511 struct l2cap_cmd_hdr *cmd,
5512 u16 cmd_len, void *data)
5513{
5514 struct l2cap_move_chan_cfm *cfm = data;
5515 struct l2cap_chan *chan;
5516 u16 icid, result;
5517
5518 if (cmd_len != sizeof(*cfm))
5519 return -EPROTO;
5520
5521 icid = le16_to_cpu(cfm->icid);
5522 result = le16_to_cpu(cfm->result);
5523
5524 BT_DBG("icid 0x%4.4x, result 0x%4.4x", icid, result);
5525
5526 chan = l2cap_get_chan_by_dcid(conn, icid);
5527 if (!chan) {
5528 /* Spec requires a response even if the icid was not found */
5529 l2cap_send_move_chan_cfm_rsp(conn, cmd->ident, icid);
5530 return 0;
5531 }
5532
5533 if (chan->move_state == L2CAP_MOVE_WAIT_CONFIRM) {
5534 if (result == L2CAP_MC_CONFIRMED) {
5535 chan->local_amp_id = chan->move_id;
5536 if (chan->local_amp_id == AMP_ID_BREDR)
5537 __release_logical_link(chan);
5538 } else {
5539 chan->move_id = chan->local_amp_id;
5540 }
5541
5542 l2cap_move_done(chan);
5543 }
5544
5545 l2cap_send_move_chan_cfm_rsp(conn, cmd->ident, icid);
5546
5547 l2cap_chan_unlock(chan);
5548 l2cap_chan_put(chan);
5549
5550 return 0;
5551}
5552
5553static inline int l2cap_move_channel_confirm_rsp(struct l2cap_conn *conn,
5554 struct l2cap_cmd_hdr *cmd,
5555 u16 cmd_len, void *data)
5556{
5557 struct l2cap_move_chan_cfm_rsp *rsp = data;
5558 struct l2cap_chan *chan;
5559 u16 icid;
5560
5561 if (cmd_len != sizeof(*rsp))
5562 return -EPROTO;
5563
5564 icid = le16_to_cpu(rsp->icid);
5565
5566 BT_DBG("icid 0x%4.4x", icid);
5567
5568 chan = l2cap_get_chan_by_scid(conn, icid);
5569 if (!chan)
5570 return 0;
5571
5572 __clear_chan_timer(chan);
5573
5574 if (chan->move_state == L2CAP_MOVE_WAIT_CONFIRM_RSP) {
5575 chan->local_amp_id = chan->move_id;
5576
5577 if (chan->local_amp_id == AMP_ID_BREDR && chan->hs_hchan)
5578 __release_logical_link(chan);
5579
5580 l2cap_move_done(chan);
5581 }
5582
5583 l2cap_chan_unlock(chan);
5584 l2cap_chan_put(chan);
5585
5586 return 0;
5587}
5588
5589static inline int l2cap_conn_param_update_req(struct l2cap_conn *conn,
5590 struct l2cap_cmd_hdr *cmd,
5591 u16 cmd_len, u8 *data)
5592{
5593 struct hci_conn *hcon = conn->hcon;
5594 struct l2cap_conn_param_update_req *req;
5595 struct l2cap_conn_param_update_rsp rsp;
5596 u16 min, max, latency, to_multiplier;
5597 int err;
5598
5599 if (hcon->role != HCI_ROLE_MASTER)
5600 return -EINVAL;
5601
5602 if (cmd_len != sizeof(struct l2cap_conn_param_update_req))
5603 return -EPROTO;
5604
5605 req = (struct l2cap_conn_param_update_req *) data;
5606 min = __le16_to_cpu(req->min);
5607 max = __le16_to_cpu(req->max);
5608 latency = __le16_to_cpu(req->latency);
5609 to_multiplier = __le16_to_cpu(req->to_multiplier);
5610
5611 BT_DBG("min 0x%4.4x max 0x%4.4x latency: 0x%4.4x Timeout: 0x%4.4x",
5612 min, max, latency, to_multiplier);
5613
5614 memset(&rsp, 0, sizeof(rsp));
5615
5616 if (max > hcon->le_conn_max_interval) {
5617 BT_DBG("requested connection interval exceeds current bounds.");
5618 err = -EINVAL;
5619 } else {
5620 err = hci_check_conn_params(min, max, latency, to_multiplier);
5621 }
5622
5623 if (err)
5624 rsp.result = cpu_to_le16(L2CAP_CONN_PARAM_REJECTED);
5625 else
5626 rsp.result = cpu_to_le16(L2CAP_CONN_PARAM_ACCEPTED);
5627
5628 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONN_PARAM_UPDATE_RSP,
5629 sizeof(rsp), &rsp);
5630
5631 if (!err) {
5632 u8 store_hint;
5633
5634 store_hint = hci_le_conn_update(hcon, min, max, latency,
5635 to_multiplier);
5636 mgmt_new_conn_param(hcon->hdev, &hcon->dst, hcon->dst_type,
5637 store_hint, min, max, latency,
5638 to_multiplier);
5639
5640 }
5641
5642 return 0;
5643}
5644
5645static int l2cap_le_connect_rsp(struct l2cap_conn *conn,
5646 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5647 u8 *data)
5648{
5649 struct l2cap_le_conn_rsp *rsp = (struct l2cap_le_conn_rsp *) data;
5650 struct hci_conn *hcon = conn->hcon;
5651 u16 dcid, mtu, mps, credits, result;
5652 struct l2cap_chan *chan;
5653 int err, sec_level;
5654
5655 if (cmd_len < sizeof(*rsp))
5656 return -EPROTO;
5657
5658 dcid = __le16_to_cpu(rsp->dcid);
5659 mtu = __le16_to_cpu(rsp->mtu);
5660 mps = __le16_to_cpu(rsp->mps);
5661 credits = __le16_to_cpu(rsp->credits);
5662 result = __le16_to_cpu(rsp->result);
5663
5664 if (result == L2CAP_CR_LE_SUCCESS && (mtu < 23 || mps < 23 ||
5665 dcid < L2CAP_CID_DYN_START ||
5666 dcid > L2CAP_CID_LE_DYN_END))
5667 return -EPROTO;
5668
5669 BT_DBG("dcid 0x%4.4x mtu %u mps %u credits %u result 0x%2.2x",
5670 dcid, mtu, mps, credits, result);
5671
5672 mutex_lock(&conn->chan_lock);
5673
5674 chan = __l2cap_get_chan_by_ident(conn, cmd->ident);
5675 if (!chan) {
5676 err = -EBADSLT;
5677 goto unlock;
5678 }
5679
5680 err = 0;
5681
5682 l2cap_chan_lock(chan);
5683
5684 switch (result) {
5685 case L2CAP_CR_LE_SUCCESS:
5686 if (__l2cap_get_chan_by_dcid(conn, dcid)) {
5687 err = -EBADSLT;
5688 break;
5689 }
5690
5691 chan->ident = 0;
5692 chan->dcid = dcid;
5693 chan->omtu = mtu;
5694 chan->remote_mps = mps;
5695 chan->tx_credits = credits;
5696 l2cap_chan_ready(chan);
5697 break;
5698
5699 case L2CAP_CR_LE_AUTHENTICATION:
5700 case L2CAP_CR_LE_ENCRYPTION:
5701 /* If we already have MITM protection we can't do
5702 * anything.
5703 */
5704 if (hcon->sec_level > BT_SECURITY_MEDIUM) {
5705 l2cap_chan_del(chan, ECONNREFUSED);
5706 break;
5707 }
5708
5709 sec_level = hcon->sec_level + 1;
5710 if (chan->sec_level < sec_level)
5711 chan->sec_level = sec_level;
5712
5713 /* We'll need to send a new Connect Request */
5714 clear_bit(FLAG_LE_CONN_REQ_SENT, &chan->flags);
5715
5716 smp_conn_security(hcon, chan->sec_level);
5717 break;
5718
5719 default:
5720 l2cap_chan_del(chan, ECONNREFUSED);
5721 break;
5722 }
5723
5724 l2cap_chan_unlock(chan);
5725
5726unlock:
5727 mutex_unlock(&conn->chan_lock);
5728
5729 return err;
5730}
5731
5732static inline int l2cap_bredr_sig_cmd(struct l2cap_conn *conn,
5733 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5734 u8 *data)
5735{
5736 int err = 0;
5737
5738 switch (cmd->code) {
5739 case L2CAP_COMMAND_REJ:
5740 l2cap_command_rej(conn, cmd, cmd_len, data);
5741 break;
5742
5743 case L2CAP_CONN_REQ:
5744 err = l2cap_connect_req(conn, cmd, cmd_len, data);
5745 break;
5746
5747 case L2CAP_CONN_RSP:
5748 case L2CAP_CREATE_CHAN_RSP:
5749 l2cap_connect_create_rsp(conn, cmd, cmd_len, data);
5750 break;
5751
5752 case L2CAP_CONF_REQ:
5753 err = l2cap_config_req(conn, cmd, cmd_len, data);
5754 break;
5755
5756 case L2CAP_CONF_RSP:
5757 l2cap_config_rsp(conn, cmd, cmd_len, data);
5758 break;
5759
5760 case L2CAP_DISCONN_REQ:
5761 err = l2cap_disconnect_req(conn, cmd, cmd_len, data);
5762 break;
5763
5764 case L2CAP_DISCONN_RSP:
5765 l2cap_disconnect_rsp(conn, cmd, cmd_len, data);
5766 break;
5767
5768 case L2CAP_ECHO_REQ:
5769 l2cap_send_cmd(conn, cmd->ident, L2CAP_ECHO_RSP, cmd_len, data);
5770 break;
5771
5772 case L2CAP_ECHO_RSP:
5773 break;
5774
5775 case L2CAP_INFO_REQ:
5776 err = l2cap_information_req(conn, cmd, cmd_len, data);
5777 break;
5778
5779 case L2CAP_INFO_RSP:
5780 l2cap_information_rsp(conn, cmd, cmd_len, data);
5781 break;
5782
5783 case L2CAP_CREATE_CHAN_REQ:
5784 err = l2cap_create_channel_req(conn, cmd, cmd_len, data);
5785 break;
5786
5787 case L2CAP_MOVE_CHAN_REQ:
5788 err = l2cap_move_channel_req(conn, cmd, cmd_len, data);
5789 break;
5790
5791 case L2CAP_MOVE_CHAN_RSP:
5792 l2cap_move_channel_rsp(conn, cmd, cmd_len, data);
5793 break;
5794
5795 case L2CAP_MOVE_CHAN_CFM:
5796 err = l2cap_move_channel_confirm(conn, cmd, cmd_len, data);
5797 break;
5798
5799 case L2CAP_MOVE_CHAN_CFM_RSP:
5800 l2cap_move_channel_confirm_rsp(conn, cmd, cmd_len, data);
5801 break;
5802
5803 default:
5804 BT_ERR("Unknown BR/EDR signaling command 0x%2.2x", cmd->code);
5805 err = -EINVAL;
5806 break;
5807 }
5808
5809 return err;
5810}
5811
5812static int l2cap_le_connect_req(struct l2cap_conn *conn,
5813 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5814 u8 *data)
5815{
5816 struct l2cap_le_conn_req *req = (struct l2cap_le_conn_req *) data;
5817 struct l2cap_le_conn_rsp rsp;
5818 struct l2cap_chan *chan, *pchan;
5819 u16 dcid, scid, credits, mtu, mps;
5820 __le16 psm;
5821 u8 result;
5822
5823 if (cmd_len != sizeof(*req))
5824 return -EPROTO;
5825
5826 scid = __le16_to_cpu(req->scid);
5827 mtu = __le16_to_cpu(req->mtu);
5828 mps = __le16_to_cpu(req->mps);
5829 psm = req->psm;
5830 dcid = 0;
5831 credits = 0;
5832
5833 if (mtu < 23 || mps < 23)
5834 return -EPROTO;
5835
5836 BT_DBG("psm 0x%2.2x scid 0x%4.4x mtu %u mps %u", __le16_to_cpu(psm),
5837 scid, mtu, mps);
5838
5839 /* BLUETOOTH CORE SPECIFICATION Version 5.3 | Vol 3, Part A
5840 * page 1059:
5841 *
5842 * Valid range: 0x0001-0x00ff
5843 *
5844 * Table 4.15: L2CAP_LE_CREDIT_BASED_CONNECTION_REQ SPSM ranges
5845 */
5846 if (!psm || __le16_to_cpu(psm) > L2CAP_PSM_LE_DYN_END) {
5847 result = L2CAP_CR_LE_BAD_PSM;
5848 chan = NULL;
5849 goto response;
5850 }
5851
5852 /* Check if we have socket listening on psm */
5853 pchan = l2cap_global_chan_by_psm(BT_LISTEN, psm, &conn->hcon->src,
5854 &conn->hcon->dst, LE_LINK);
5855 if (!pchan) {
5856 result = L2CAP_CR_LE_BAD_PSM;
5857 chan = NULL;
5858 goto response;
5859 }
5860
5861 mutex_lock(&conn->chan_lock);
5862 l2cap_chan_lock(pchan);
5863
5864 if (!smp_sufficient_security(conn->hcon, pchan->sec_level,
5865 SMP_ALLOW_STK)) {
5866 result = L2CAP_CR_LE_AUTHENTICATION;
5867 chan = NULL;
5868 goto response_unlock;
5869 }
5870
5871 /* Check for valid dynamic CID range */
5872 if (scid < L2CAP_CID_DYN_START || scid > L2CAP_CID_LE_DYN_END) {
5873 result = L2CAP_CR_LE_INVALID_SCID;
5874 chan = NULL;
5875 goto response_unlock;
5876 }
5877
5878 /* Check if we already have channel with that dcid */
5879 if (__l2cap_get_chan_by_dcid(conn, scid)) {
5880 result = L2CAP_CR_LE_SCID_IN_USE;
5881 chan = NULL;
5882 goto response_unlock;
5883 }
5884
5885 chan = pchan->ops->new_connection(pchan);
5886 if (!chan) {
5887 result = L2CAP_CR_LE_NO_MEM;
5888 goto response_unlock;
5889 }
5890
5891 bacpy(&chan->src, &conn->hcon->src);
5892 bacpy(&chan->dst, &conn->hcon->dst);
5893 chan->src_type = bdaddr_src_type(conn->hcon);
5894 chan->dst_type = bdaddr_dst_type(conn->hcon);
5895 chan->psm = psm;
5896 chan->dcid = scid;
5897 chan->omtu = mtu;
5898 chan->remote_mps = mps;
5899
5900 __l2cap_chan_add(conn, chan);
5901
5902 l2cap_le_flowctl_init(chan, __le16_to_cpu(req->credits));
5903
5904 dcid = chan->scid;
5905 credits = chan->rx_credits;
5906
5907 __set_chan_timer(chan, chan->ops->get_sndtimeo(chan));
5908
5909 chan->ident = cmd->ident;
5910
5911 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) {
5912 l2cap_state_change(chan, BT_CONNECT2);
5913 /* The following result value is actually not defined
5914 * for LE CoC but we use it to let the function know
5915 * that it should bail out after doing its cleanup
5916 * instead of sending a response.
5917 */
5918 result = L2CAP_CR_PEND;
5919 chan->ops->defer(chan);
5920 } else {
5921 l2cap_chan_ready(chan);
5922 result = L2CAP_CR_LE_SUCCESS;
5923 }
5924
5925response_unlock:
5926 l2cap_chan_unlock(pchan);
5927 mutex_unlock(&conn->chan_lock);
5928 l2cap_chan_put(pchan);
5929
5930 if (result == L2CAP_CR_PEND)
5931 return 0;
5932
5933response:
5934 if (chan) {
5935 rsp.mtu = cpu_to_le16(chan->imtu);
5936 rsp.mps = cpu_to_le16(chan->mps);
5937 } else {
5938 rsp.mtu = 0;
5939 rsp.mps = 0;
5940 }
5941
5942 rsp.dcid = cpu_to_le16(dcid);
5943 rsp.credits = cpu_to_le16(credits);
5944 rsp.result = cpu_to_le16(result);
5945
5946 l2cap_send_cmd(conn, cmd->ident, L2CAP_LE_CONN_RSP, sizeof(rsp), &rsp);
5947
5948 return 0;
5949}
5950
5951static inline int l2cap_le_credits(struct l2cap_conn *conn,
5952 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5953 u8 *data)
5954{
5955 struct l2cap_le_credits *pkt;
5956 struct l2cap_chan *chan;
5957 u16 cid, credits, max_credits;
5958
5959 if (cmd_len != sizeof(*pkt))
5960 return -EPROTO;
5961
5962 pkt = (struct l2cap_le_credits *) data;
5963 cid = __le16_to_cpu(pkt->cid);
5964 credits = __le16_to_cpu(pkt->credits);
5965
5966 BT_DBG("cid 0x%4.4x credits 0x%4.4x", cid, credits);
5967
5968 chan = l2cap_get_chan_by_dcid(conn, cid);
5969 if (!chan)
5970 return -EBADSLT;
5971
5972 max_credits = LE_FLOWCTL_MAX_CREDITS - chan->tx_credits;
5973 if (credits > max_credits) {
5974 BT_ERR("LE credits overflow");
5975 l2cap_send_disconn_req(chan, ECONNRESET);
5976
5977 /* Return 0 so that we don't trigger an unnecessary
5978 * command reject packet.
5979 */
5980 goto unlock;
5981 }
5982
5983 chan->tx_credits += credits;
5984
5985 /* Resume sending */
5986 l2cap_le_flowctl_send(chan);
5987
5988 if (chan->tx_credits)
5989 chan->ops->resume(chan);
5990
5991unlock:
5992 l2cap_chan_unlock(chan);
5993 l2cap_chan_put(chan);
5994
5995 return 0;
5996}
5997
5998static inline int l2cap_ecred_conn_req(struct l2cap_conn *conn,
5999 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
6000 u8 *data)
6001{
6002 struct l2cap_ecred_conn_req *req = (void *) data;
6003 struct {
6004 struct l2cap_ecred_conn_rsp rsp;
6005 __le16 dcid[L2CAP_ECRED_MAX_CID];
6006 } __packed pdu;
6007 struct l2cap_chan *chan, *pchan;
6008 u16 mtu, mps;
6009 __le16 psm;
6010 u8 result, len = 0;
6011 int i, num_scid;
6012 bool defer = false;
6013
6014 if (!enable_ecred)
6015 return -EINVAL;
6016
6017 if (cmd_len < sizeof(*req) || (cmd_len - sizeof(*req)) % sizeof(u16)) {
6018 result = L2CAP_CR_LE_INVALID_PARAMS;
6019 goto response;
6020 }
6021
6022 cmd_len -= sizeof(*req);
6023 num_scid = cmd_len / sizeof(u16);
6024
6025 if (num_scid > ARRAY_SIZE(pdu.dcid)) {
6026 result = L2CAP_CR_LE_INVALID_PARAMS;
6027 goto response;
6028 }
6029
6030 mtu = __le16_to_cpu(req->mtu);
6031 mps = __le16_to_cpu(req->mps);
6032
6033 if (mtu < L2CAP_ECRED_MIN_MTU || mps < L2CAP_ECRED_MIN_MPS) {
6034 result = L2CAP_CR_LE_UNACCEPT_PARAMS;
6035 goto response;
6036 }
6037
6038 psm = req->psm;
6039
6040 /* BLUETOOTH CORE SPECIFICATION Version 5.3 | Vol 3, Part A
6041 * page 1059:
6042 *
6043 * Valid range: 0x0001-0x00ff
6044 *
6045 * Table 4.15: L2CAP_LE_CREDIT_BASED_CONNECTION_REQ SPSM ranges
6046 */
6047 if (!psm || __le16_to_cpu(psm) > L2CAP_PSM_LE_DYN_END) {
6048 result = L2CAP_CR_LE_BAD_PSM;
6049 goto response;
6050 }
6051
6052 BT_DBG("psm 0x%2.2x mtu %u mps %u", __le16_to_cpu(psm), mtu, mps);
6053
6054 memset(&pdu, 0, sizeof(pdu));
6055
6056 /* Check if we have socket listening on psm */
6057 pchan = l2cap_global_chan_by_psm(BT_LISTEN, psm, &conn->hcon->src,
6058 &conn->hcon->dst, LE_LINK);
6059 if (!pchan) {
6060 result = L2CAP_CR_LE_BAD_PSM;
6061 goto response;
6062 }
6063
6064 mutex_lock(&conn->chan_lock);
6065 l2cap_chan_lock(pchan);
6066
6067 if (!smp_sufficient_security(conn->hcon, pchan->sec_level,
6068 SMP_ALLOW_STK)) {
6069 result = L2CAP_CR_LE_AUTHENTICATION;
6070 goto unlock;
6071 }
6072
6073 result = L2CAP_CR_LE_SUCCESS;
6074
6075 for (i = 0; i < num_scid; i++) {
6076 u16 scid = __le16_to_cpu(req->scid[i]);
6077
6078 BT_DBG("scid[%d] 0x%4.4x", i, scid);
6079
6080 pdu.dcid[i] = 0x0000;
6081 len += sizeof(*pdu.dcid);
6082
6083 /* Check for valid dynamic CID range */
6084 if (scid < L2CAP_CID_DYN_START || scid > L2CAP_CID_LE_DYN_END) {
6085 result = L2CAP_CR_LE_INVALID_SCID;
6086 continue;
6087 }
6088
6089 /* Check if we already have channel with that dcid */
6090 if (__l2cap_get_chan_by_dcid(conn, scid)) {
6091 result = L2CAP_CR_LE_SCID_IN_USE;
6092 continue;
6093 }
6094
6095 chan = pchan->ops->new_connection(pchan);
6096 if (!chan) {
6097 result = L2CAP_CR_LE_NO_MEM;
6098 continue;
6099 }
6100
6101 bacpy(&chan->src, &conn->hcon->src);
6102 bacpy(&chan->dst, &conn->hcon->dst);
6103 chan->src_type = bdaddr_src_type(conn->hcon);
6104 chan->dst_type = bdaddr_dst_type(conn->hcon);
6105 chan->psm = psm;
6106 chan->dcid = scid;
6107 chan->omtu = mtu;
6108 chan->remote_mps = mps;
6109
6110 __l2cap_chan_add(conn, chan);
6111
6112 l2cap_ecred_init(chan, __le16_to_cpu(req->credits));
6113
6114 /* Init response */
6115 if (!pdu.rsp.credits) {
6116 pdu.rsp.mtu = cpu_to_le16(chan->imtu);
6117 pdu.rsp.mps = cpu_to_le16(chan->mps);
6118 pdu.rsp.credits = cpu_to_le16(chan->rx_credits);
6119 }
6120
6121 pdu.dcid[i] = cpu_to_le16(chan->scid);
6122
6123 __set_chan_timer(chan, chan->ops->get_sndtimeo(chan));
6124
6125 chan->ident = cmd->ident;
6126 chan->mode = L2CAP_MODE_EXT_FLOWCTL;
6127
6128 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) {
6129 l2cap_state_change(chan, BT_CONNECT2);
6130 defer = true;
6131 chan->ops->defer(chan);
6132 } else {
6133 l2cap_chan_ready(chan);
6134 }
6135 }
6136
6137unlock:
6138 l2cap_chan_unlock(pchan);
6139 mutex_unlock(&conn->chan_lock);
6140 l2cap_chan_put(pchan);
6141
6142response:
6143 pdu.rsp.result = cpu_to_le16(result);
6144
6145 if (defer)
6146 return 0;
6147
6148 l2cap_send_cmd(conn, cmd->ident, L2CAP_ECRED_CONN_RSP,
6149 sizeof(pdu.rsp) + len, &pdu);
6150
6151 return 0;
6152}
6153
6154static inline int l2cap_ecred_conn_rsp(struct l2cap_conn *conn,
6155 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
6156 u8 *data)
6157{
6158 struct l2cap_ecred_conn_rsp *rsp = (void *) data;
6159 struct hci_conn *hcon = conn->hcon;
6160 u16 mtu, mps, credits, result;
6161 struct l2cap_chan *chan, *tmp;
6162 int err = 0, sec_level;
6163 int i = 0;
6164
6165 if (cmd_len < sizeof(*rsp))
6166 return -EPROTO;
6167
6168 mtu = __le16_to_cpu(rsp->mtu);
6169 mps = __le16_to_cpu(rsp->mps);
6170 credits = __le16_to_cpu(rsp->credits);
6171 result = __le16_to_cpu(rsp->result);
6172
6173 BT_DBG("mtu %u mps %u credits %u result 0x%4.4x", mtu, mps, credits,
6174 result);
6175
6176 mutex_lock(&conn->chan_lock);
6177
6178 cmd_len -= sizeof(*rsp);
6179
6180 list_for_each_entry_safe(chan, tmp, &conn->chan_l, list) {
6181 u16 dcid;
6182
6183 if (chan->ident != cmd->ident ||
6184 chan->mode != L2CAP_MODE_EXT_FLOWCTL ||
6185 chan->state == BT_CONNECTED)
6186 continue;
6187
6188 l2cap_chan_lock(chan);
6189
6190 /* Check that there is a dcid for each pending channel */
6191 if (cmd_len < sizeof(dcid)) {
6192 l2cap_chan_del(chan, ECONNREFUSED);
6193 l2cap_chan_unlock(chan);
6194 continue;
6195 }
6196
6197 dcid = __le16_to_cpu(rsp->dcid[i++]);
6198 cmd_len -= sizeof(u16);
6199
6200 BT_DBG("dcid[%d] 0x%4.4x", i, dcid);
6201
6202 /* Check if dcid is already in use */
6203 if (dcid && __l2cap_get_chan_by_dcid(conn, dcid)) {
6204 /* If a device receives a
6205 * L2CAP_CREDIT_BASED_CONNECTION_RSP packet with an
6206 * already-assigned Destination CID, then both the
6207 * original channel and the new channel shall be
6208 * immediately discarded and not used.
6209 */
6210 l2cap_chan_del(chan, ECONNREFUSED);
6211 l2cap_chan_unlock(chan);
6212 chan = __l2cap_get_chan_by_dcid(conn, dcid);
6213 l2cap_chan_lock(chan);
6214 l2cap_chan_del(chan, ECONNRESET);
6215 l2cap_chan_unlock(chan);
6216 continue;
6217 }
6218
6219 switch (result) {
6220 case L2CAP_CR_LE_AUTHENTICATION:
6221 case L2CAP_CR_LE_ENCRYPTION:
6222 /* If we already have MITM protection we can't do
6223 * anything.
6224 */
6225 if (hcon->sec_level > BT_SECURITY_MEDIUM) {
6226 l2cap_chan_del(chan, ECONNREFUSED);
6227 break;
6228 }
6229
6230 sec_level = hcon->sec_level + 1;
6231 if (chan->sec_level < sec_level)
6232 chan->sec_level = sec_level;
6233
6234 /* We'll need to send a new Connect Request */
6235 clear_bit(FLAG_ECRED_CONN_REQ_SENT, &chan->flags);
6236
6237 smp_conn_security(hcon, chan->sec_level);
6238 break;
6239
6240 case L2CAP_CR_LE_BAD_PSM:
6241 l2cap_chan_del(chan, ECONNREFUSED);
6242 break;
6243
6244 default:
6245 /* If dcid was not set it means channels was refused */
6246 if (!dcid) {
6247 l2cap_chan_del(chan, ECONNREFUSED);
6248 break;
6249 }
6250
6251 chan->ident = 0;
6252 chan->dcid = dcid;
6253 chan->omtu = mtu;
6254 chan->remote_mps = mps;
6255 chan->tx_credits = credits;
6256 l2cap_chan_ready(chan);
6257 break;
6258 }
6259
6260 l2cap_chan_unlock(chan);
6261 }
6262
6263 mutex_unlock(&conn->chan_lock);
6264
6265 return err;
6266}
6267
6268static inline int l2cap_ecred_reconf_req(struct l2cap_conn *conn,
6269 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
6270 u8 *data)
6271{
6272 struct l2cap_ecred_reconf_req *req = (void *) data;
6273 struct l2cap_ecred_reconf_rsp rsp;
6274 u16 mtu, mps, result;
6275 struct l2cap_chan *chan;
6276 int i, num_scid;
6277
6278 if (!enable_ecred)
6279 return -EINVAL;
6280
6281 if (cmd_len < sizeof(*req) || cmd_len - sizeof(*req) % sizeof(u16)) {
6282 result = L2CAP_CR_LE_INVALID_PARAMS;
6283 goto respond;
6284 }
6285
6286 mtu = __le16_to_cpu(req->mtu);
6287 mps = __le16_to_cpu(req->mps);
6288
6289 BT_DBG("mtu %u mps %u", mtu, mps);
6290
6291 if (mtu < L2CAP_ECRED_MIN_MTU) {
6292 result = L2CAP_RECONF_INVALID_MTU;
6293 goto respond;
6294 }
6295
6296 if (mps < L2CAP_ECRED_MIN_MPS) {
6297 result = L2CAP_RECONF_INVALID_MPS;
6298 goto respond;
6299 }
6300
6301 cmd_len -= sizeof(*req);
6302 num_scid = cmd_len / sizeof(u16);
6303 result = L2CAP_RECONF_SUCCESS;
6304
6305 for (i = 0; i < num_scid; i++) {
6306 u16 scid;
6307
6308 scid = __le16_to_cpu(req->scid[i]);
6309 if (!scid)
6310 return -EPROTO;
6311
6312 chan = __l2cap_get_chan_by_dcid(conn, scid);
6313 if (!chan)
6314 continue;
6315
6316 /* If the MTU value is decreased for any of the included
6317 * channels, then the receiver shall disconnect all
6318 * included channels.
6319 */
6320 if (chan->omtu > mtu) {
6321 BT_ERR("chan %p decreased MTU %u -> %u", chan,
6322 chan->omtu, mtu);
6323 result = L2CAP_RECONF_INVALID_MTU;
6324 }
6325
6326 chan->omtu = mtu;
6327 chan->remote_mps = mps;
6328 }
6329
6330respond:
6331 rsp.result = cpu_to_le16(result);
6332
6333 l2cap_send_cmd(conn, cmd->ident, L2CAP_ECRED_RECONF_RSP, sizeof(rsp),
6334 &rsp);
6335
6336 return 0;
6337}
6338
6339static inline int l2cap_ecred_reconf_rsp(struct l2cap_conn *conn,
6340 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
6341 u8 *data)
6342{
6343 struct l2cap_chan *chan, *tmp;
6344 struct l2cap_ecred_conn_rsp *rsp = (void *) data;
6345 u16 result;
6346
6347 if (cmd_len < sizeof(*rsp))
6348 return -EPROTO;
6349
6350 result = __le16_to_cpu(rsp->result);
6351
6352 BT_DBG("result 0x%4.4x", rsp->result);
6353
6354 if (!result)
6355 return 0;
6356
6357 list_for_each_entry_safe(chan, tmp, &conn->chan_l, list) {
6358 if (chan->ident != cmd->ident)
6359 continue;
6360
6361 l2cap_chan_del(chan, ECONNRESET);
6362 }
6363
6364 return 0;
6365}
6366
6367static inline int l2cap_le_command_rej(struct l2cap_conn *conn,
6368 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
6369 u8 *data)
6370{
6371 struct l2cap_cmd_rej_unk *rej = (struct l2cap_cmd_rej_unk *) data;
6372 struct l2cap_chan *chan;
6373
6374 if (cmd_len < sizeof(*rej))
6375 return -EPROTO;
6376
6377 mutex_lock(&conn->chan_lock);
6378
6379 chan = __l2cap_get_chan_by_ident(conn, cmd->ident);
6380 if (!chan)
6381 goto done;
6382
6383 chan = l2cap_chan_hold_unless_zero(chan);
6384 if (!chan)
6385 goto done;
6386
6387 l2cap_chan_lock(chan);
6388 l2cap_chan_del(chan, ECONNREFUSED);
6389 l2cap_chan_unlock(chan);
6390 l2cap_chan_put(chan);
6391
6392done:
6393 mutex_unlock(&conn->chan_lock);
6394 return 0;
6395}
6396
6397static inline int l2cap_le_sig_cmd(struct l2cap_conn *conn,
6398 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
6399 u8 *data)
6400{
6401 int err = 0;
6402
6403 switch (cmd->code) {
6404 case L2CAP_COMMAND_REJ:
6405 l2cap_le_command_rej(conn, cmd, cmd_len, data);
6406 break;
6407
6408 case L2CAP_CONN_PARAM_UPDATE_REQ:
6409 err = l2cap_conn_param_update_req(conn, cmd, cmd_len, data);
6410 break;
6411
6412 case L2CAP_CONN_PARAM_UPDATE_RSP:
6413 break;
6414
6415 case L2CAP_LE_CONN_RSP:
6416 l2cap_le_connect_rsp(conn, cmd, cmd_len, data);
6417 break;
6418
6419 case L2CAP_LE_CONN_REQ:
6420 err = l2cap_le_connect_req(conn, cmd, cmd_len, data);
6421 break;
6422
6423 case L2CAP_LE_CREDITS:
6424 err = l2cap_le_credits(conn, cmd, cmd_len, data);
6425 break;
6426
6427 case L2CAP_ECRED_CONN_REQ:
6428 err = l2cap_ecred_conn_req(conn, cmd, cmd_len, data);
6429 break;
6430
6431 case L2CAP_ECRED_CONN_RSP:
6432 err = l2cap_ecred_conn_rsp(conn, cmd, cmd_len, data);
6433 break;
6434
6435 case L2CAP_ECRED_RECONF_REQ:
6436 err = l2cap_ecred_reconf_req(conn, cmd, cmd_len, data);
6437 break;
6438
6439 case L2CAP_ECRED_RECONF_RSP:
6440 err = l2cap_ecred_reconf_rsp(conn, cmd, cmd_len, data);
6441 break;
6442
6443 case L2CAP_DISCONN_REQ:
6444 err = l2cap_disconnect_req(conn, cmd, cmd_len, data);
6445 break;
6446
6447 case L2CAP_DISCONN_RSP:
6448 l2cap_disconnect_rsp(conn, cmd, cmd_len, data);
6449 break;
6450
6451 default:
6452 BT_ERR("Unknown LE signaling command 0x%2.2x", cmd->code);
6453 err = -EINVAL;
6454 break;
6455 }
6456
6457 return err;
6458}
6459
6460static inline void l2cap_le_sig_channel(struct l2cap_conn *conn,
6461 struct sk_buff *skb)
6462{
6463 struct hci_conn *hcon = conn->hcon;
6464 struct l2cap_cmd_hdr *cmd;
6465 u16 len;
6466 int err;
6467
6468 if (hcon->type != LE_LINK)
6469 goto drop;
6470
6471 if (skb->len < L2CAP_CMD_HDR_SIZE)
6472 goto drop;
6473
6474 cmd = (void *) skb->data;
6475 skb_pull(skb, L2CAP_CMD_HDR_SIZE);
6476
6477 len = le16_to_cpu(cmd->len);
6478
6479 BT_DBG("code 0x%2.2x len %d id 0x%2.2x", cmd->code, len, cmd->ident);
6480
6481 if (len != skb->len || !cmd->ident) {
6482 BT_DBG("corrupted command");
6483 goto drop;
6484 }
6485
6486 err = l2cap_le_sig_cmd(conn, cmd, len, skb->data);
6487 if (err) {
6488 struct l2cap_cmd_rej_unk rej;
6489
6490 BT_ERR("Wrong link type (%d)", err);
6491
6492 rej.reason = cpu_to_le16(L2CAP_REJ_NOT_UNDERSTOOD);
6493 l2cap_send_cmd(conn, cmd->ident, L2CAP_COMMAND_REJ,
6494 sizeof(rej), &rej);
6495 }
6496
6497drop:
6498 kfree_skb(skb);
6499}
6500
6501static inline void l2cap_sig_send_rej(struct l2cap_conn *conn, u16 ident)
6502{
6503 struct l2cap_cmd_rej_unk rej;
6504
6505 rej.reason = cpu_to_le16(L2CAP_REJ_NOT_UNDERSTOOD);
6506 l2cap_send_cmd(conn, ident, L2CAP_COMMAND_REJ, sizeof(rej), &rej);
6507}
6508
6509static inline void l2cap_sig_channel(struct l2cap_conn *conn,
6510 struct sk_buff *skb)
6511{
6512 struct hci_conn *hcon = conn->hcon;
6513 struct l2cap_cmd_hdr *cmd;
6514 int err;
6515
6516 l2cap_raw_recv(conn, skb);
6517
6518 if (hcon->type != ACL_LINK)
6519 goto drop;
6520
6521 while (skb->len >= L2CAP_CMD_HDR_SIZE) {
6522 u16 len;
6523
6524 cmd = (void *) skb->data;
6525 skb_pull(skb, L2CAP_CMD_HDR_SIZE);
6526
6527 len = le16_to_cpu(cmd->len);
6528
6529 BT_DBG("code 0x%2.2x len %d id 0x%2.2x", cmd->code, len,
6530 cmd->ident);
6531
6532 if (len > skb->len || !cmd->ident) {
6533 BT_DBG("corrupted command");
6534 l2cap_sig_send_rej(conn, cmd->ident);
6535 skb_pull(skb, len > skb->len ? skb->len : len);
6536 continue;
6537 }
6538
6539 err = l2cap_bredr_sig_cmd(conn, cmd, len, skb->data);
6540 if (err) {
6541 BT_ERR("Wrong link type (%d)", err);
6542 l2cap_sig_send_rej(conn, cmd->ident);
6543 }
6544
6545 skb_pull(skb, len);
6546 }
6547
6548 if (skb->len > 0) {
6549 BT_DBG("corrupted command");
6550 l2cap_sig_send_rej(conn, 0);
6551 }
6552
6553drop:
6554 kfree_skb(skb);
6555}
6556
6557static int l2cap_check_fcs(struct l2cap_chan *chan, struct sk_buff *skb)
6558{
6559 u16 our_fcs, rcv_fcs;
6560 int hdr_size;
6561
6562 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
6563 hdr_size = L2CAP_EXT_HDR_SIZE;
6564 else
6565 hdr_size = L2CAP_ENH_HDR_SIZE;
6566
6567 if (chan->fcs == L2CAP_FCS_CRC16) {
6568 skb_trim(skb, skb->len - L2CAP_FCS_SIZE);
6569 rcv_fcs = get_unaligned_le16(skb->data + skb->len);
6570 our_fcs = crc16(0, skb->data - hdr_size, skb->len + hdr_size);
6571
6572 if (our_fcs != rcv_fcs)
6573 return -EBADMSG;
6574 }
6575 return 0;
6576}
6577
6578static void l2cap_send_i_or_rr_or_rnr(struct l2cap_chan *chan)
6579{
6580 struct l2cap_ctrl control;
6581
6582 BT_DBG("chan %p", chan);
6583
6584 memset(&control, 0, sizeof(control));
6585 control.sframe = 1;
6586 control.final = 1;
6587 control.reqseq = chan->buffer_seq;
6588 set_bit(CONN_SEND_FBIT, &chan->conn_state);
6589
6590 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
6591 control.super = L2CAP_SUPER_RNR;
6592 l2cap_send_sframe(chan, &control);
6593 }
6594
6595 if (test_and_clear_bit(CONN_REMOTE_BUSY, &chan->conn_state) &&
6596 chan->unacked_frames > 0)
6597 __set_retrans_timer(chan);
6598
6599 /* Send pending iframes */
6600 l2cap_ertm_send(chan);
6601
6602 if (!test_bit(CONN_LOCAL_BUSY, &chan->conn_state) &&
6603 test_bit(CONN_SEND_FBIT, &chan->conn_state)) {
6604 /* F-bit wasn't sent in an s-frame or i-frame yet, so
6605 * send it now.
6606 */
6607 control.super = L2CAP_SUPER_RR;
6608 l2cap_send_sframe(chan, &control);
6609 }
6610}
6611
6612static void append_skb_frag(struct sk_buff *skb, struct sk_buff *new_frag,
6613 struct sk_buff **last_frag)
6614{
6615 /* skb->len reflects data in skb as well as all fragments
6616 * skb->data_len reflects only data in fragments
6617 */
6618 if (!skb_has_frag_list(skb))
6619 skb_shinfo(skb)->frag_list = new_frag;
6620
6621 new_frag->next = NULL;
6622
6623 (*last_frag)->next = new_frag;
6624 *last_frag = new_frag;
6625
6626 skb->len += new_frag->len;
6627 skb->data_len += new_frag->len;
6628 skb->truesize += new_frag->truesize;
6629}
6630
6631static int l2cap_reassemble_sdu(struct l2cap_chan *chan, struct sk_buff *skb,
6632 struct l2cap_ctrl *control)
6633{
6634 int err = -EINVAL;
6635
6636 switch (control->sar) {
6637 case L2CAP_SAR_UNSEGMENTED:
6638 if (chan->sdu)
6639 break;
6640
6641 err = chan->ops->recv(chan, skb);
6642 break;
6643
6644 case L2CAP_SAR_START:
6645 if (chan->sdu)
6646 break;
6647
6648 if (!pskb_may_pull(skb, L2CAP_SDULEN_SIZE))
6649 break;
6650
6651 chan->sdu_len = get_unaligned_le16(skb->data);
6652 skb_pull(skb, L2CAP_SDULEN_SIZE);
6653
6654 if (chan->sdu_len > chan->imtu) {
6655 err = -EMSGSIZE;
6656 break;
6657 }
6658
6659 if (skb->len >= chan->sdu_len)
6660 break;
6661
6662 chan->sdu = skb;
6663 chan->sdu_last_frag = skb;
6664
6665 skb = NULL;
6666 err = 0;
6667 break;
6668
6669 case L2CAP_SAR_CONTINUE:
6670 if (!chan->sdu)
6671 break;
6672
6673 append_skb_frag(chan->sdu, skb,
6674 &chan->sdu_last_frag);
6675 skb = NULL;
6676
6677 if (chan->sdu->len >= chan->sdu_len)
6678 break;
6679
6680 err = 0;
6681 break;
6682
6683 case L2CAP_SAR_END:
6684 if (!chan->sdu)
6685 break;
6686
6687 append_skb_frag(chan->sdu, skb,
6688 &chan->sdu_last_frag);
6689 skb = NULL;
6690
6691 if (chan->sdu->len != chan->sdu_len)
6692 break;
6693
6694 err = chan->ops->recv(chan, chan->sdu);
6695
6696 if (!err) {
6697 /* Reassembly complete */
6698 chan->sdu = NULL;
6699 chan->sdu_last_frag = NULL;
6700 chan->sdu_len = 0;
6701 }
6702 break;
6703 }
6704
6705 if (err) {
6706 kfree_skb(skb);
6707 kfree_skb(chan->sdu);
6708 chan->sdu = NULL;
6709 chan->sdu_last_frag = NULL;
6710 chan->sdu_len = 0;
6711 }
6712
6713 return err;
6714}
6715
6716static int l2cap_resegment(struct l2cap_chan *chan)
6717{
6718 /* Placeholder */
6719 return 0;
6720}
6721
6722void l2cap_chan_busy(struct l2cap_chan *chan, int busy)
6723{
6724 u8 event;
6725
6726 if (chan->mode != L2CAP_MODE_ERTM)
6727 return;
6728
6729 event = busy ? L2CAP_EV_LOCAL_BUSY_DETECTED : L2CAP_EV_LOCAL_BUSY_CLEAR;
6730 l2cap_tx(chan, NULL, NULL, event);
6731}
6732
6733static int l2cap_rx_queued_iframes(struct l2cap_chan *chan)
6734{
6735 int err = 0;
6736 /* Pass sequential frames to l2cap_reassemble_sdu()
6737 * until a gap is encountered.
6738 */
6739
6740 BT_DBG("chan %p", chan);
6741
6742 while (!test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
6743 struct sk_buff *skb;
6744 BT_DBG("Searching for skb with txseq %d (queue len %d)",
6745 chan->buffer_seq, skb_queue_len(&chan->srej_q));
6746
6747 skb = l2cap_ertm_seq_in_queue(&chan->srej_q, chan->buffer_seq);
6748
6749 if (!skb)
6750 break;
6751
6752 skb_unlink(skb, &chan->srej_q);
6753 chan->buffer_seq = __next_seq(chan, chan->buffer_seq);
6754 err = l2cap_reassemble_sdu(chan, skb, &bt_cb(skb)->l2cap);
6755 if (err)
6756 break;
6757 }
6758
6759 if (skb_queue_empty(&chan->srej_q)) {
6760 chan->rx_state = L2CAP_RX_STATE_RECV;
6761 l2cap_send_ack(chan);
6762 }
6763
6764 return err;
6765}
6766
6767static void l2cap_handle_srej(struct l2cap_chan *chan,
6768 struct l2cap_ctrl *control)
6769{
6770 struct sk_buff *skb;
6771
6772 BT_DBG("chan %p, control %p", chan, control);
6773
6774 if (control->reqseq == chan->next_tx_seq) {
6775 BT_DBG("Invalid reqseq %d, disconnecting", control->reqseq);
6776 l2cap_send_disconn_req(chan, ECONNRESET);
6777 return;
6778 }
6779
6780 skb = l2cap_ertm_seq_in_queue(&chan->tx_q, control->reqseq);
6781
6782 if (skb == NULL) {
6783 BT_DBG("Seq %d not available for retransmission",
6784 control->reqseq);
6785 return;
6786 }
6787
6788 if (chan->max_tx != 0 && bt_cb(skb)->l2cap.retries >= chan->max_tx) {
6789 BT_DBG("Retry limit exceeded (%d)", chan->max_tx);
6790 l2cap_send_disconn_req(chan, ECONNRESET);
6791 return;
6792 }
6793
6794 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6795
6796 if (control->poll) {
6797 l2cap_pass_to_tx(chan, control);
6798
6799 set_bit(CONN_SEND_FBIT, &chan->conn_state);
6800 l2cap_retransmit(chan, control);
6801 l2cap_ertm_send(chan);
6802
6803 if (chan->tx_state == L2CAP_TX_STATE_WAIT_F) {
6804 set_bit(CONN_SREJ_ACT, &chan->conn_state);
6805 chan->srej_save_reqseq = control->reqseq;
6806 }
6807 } else {
6808 l2cap_pass_to_tx_fbit(chan, control);
6809
6810 if (control->final) {
6811 if (chan->srej_save_reqseq != control->reqseq ||
6812 !test_and_clear_bit(CONN_SREJ_ACT,
6813 &chan->conn_state))
6814 l2cap_retransmit(chan, control);
6815 } else {
6816 l2cap_retransmit(chan, control);
6817 if (chan->tx_state == L2CAP_TX_STATE_WAIT_F) {
6818 set_bit(CONN_SREJ_ACT, &chan->conn_state);
6819 chan->srej_save_reqseq = control->reqseq;
6820 }
6821 }
6822 }
6823}
6824
6825static void l2cap_handle_rej(struct l2cap_chan *chan,
6826 struct l2cap_ctrl *control)
6827{
6828 struct sk_buff *skb;
6829
6830 BT_DBG("chan %p, control %p", chan, control);
6831
6832 if (control->reqseq == chan->next_tx_seq) {
6833 BT_DBG("Invalid reqseq %d, disconnecting", control->reqseq);
6834 l2cap_send_disconn_req(chan, ECONNRESET);
6835 return;
6836 }
6837
6838 skb = l2cap_ertm_seq_in_queue(&chan->tx_q, control->reqseq);
6839
6840 if (chan->max_tx && skb &&
6841 bt_cb(skb)->l2cap.retries >= chan->max_tx) {
6842 BT_DBG("Retry limit exceeded (%d)", chan->max_tx);
6843 l2cap_send_disconn_req(chan, ECONNRESET);
6844 return;
6845 }
6846
6847 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6848
6849 l2cap_pass_to_tx(chan, control);
6850
6851 if (control->final) {
6852 if (!test_and_clear_bit(CONN_REJ_ACT, &chan->conn_state))
6853 l2cap_retransmit_all(chan, control);
6854 } else {
6855 l2cap_retransmit_all(chan, control);
6856 l2cap_ertm_send(chan);
6857 if (chan->tx_state == L2CAP_TX_STATE_WAIT_F)
6858 set_bit(CONN_REJ_ACT, &chan->conn_state);
6859 }
6860}
6861
6862static u8 l2cap_classify_txseq(struct l2cap_chan *chan, u16 txseq)
6863{
6864 BT_DBG("chan %p, txseq %d", chan, txseq);
6865
6866 BT_DBG("last_acked_seq %d, expected_tx_seq %d", chan->last_acked_seq,
6867 chan->expected_tx_seq);
6868
6869 if (chan->rx_state == L2CAP_RX_STATE_SREJ_SENT) {
6870 if (__seq_offset(chan, txseq, chan->last_acked_seq) >=
6871 chan->tx_win) {
6872 /* See notes below regarding "double poll" and
6873 * invalid packets.
6874 */
6875 if (chan->tx_win <= ((chan->tx_win_max + 1) >> 1)) {
6876 BT_DBG("Invalid/Ignore - after SREJ");
6877 return L2CAP_TXSEQ_INVALID_IGNORE;
6878 } else {
6879 BT_DBG("Invalid - in window after SREJ sent");
6880 return L2CAP_TXSEQ_INVALID;
6881 }
6882 }
6883
6884 if (chan->srej_list.head == txseq) {
6885 BT_DBG("Expected SREJ");
6886 return L2CAP_TXSEQ_EXPECTED_SREJ;
6887 }
6888
6889 if (l2cap_ertm_seq_in_queue(&chan->srej_q, txseq)) {
6890 BT_DBG("Duplicate SREJ - txseq already stored");
6891 return L2CAP_TXSEQ_DUPLICATE_SREJ;
6892 }
6893
6894 if (l2cap_seq_list_contains(&chan->srej_list, txseq)) {
6895 BT_DBG("Unexpected SREJ - not requested");
6896 return L2CAP_TXSEQ_UNEXPECTED_SREJ;
6897 }
6898 }
6899
6900 if (chan->expected_tx_seq == txseq) {
6901 if (__seq_offset(chan, txseq, chan->last_acked_seq) >=
6902 chan->tx_win) {
6903 BT_DBG("Invalid - txseq outside tx window");
6904 return L2CAP_TXSEQ_INVALID;
6905 } else {
6906 BT_DBG("Expected");
6907 return L2CAP_TXSEQ_EXPECTED;
6908 }
6909 }
6910
6911 if (__seq_offset(chan, txseq, chan->last_acked_seq) <
6912 __seq_offset(chan, chan->expected_tx_seq, chan->last_acked_seq)) {
6913 BT_DBG("Duplicate - expected_tx_seq later than txseq");
6914 return L2CAP_TXSEQ_DUPLICATE;
6915 }
6916
6917 if (__seq_offset(chan, txseq, chan->last_acked_seq) >= chan->tx_win) {
6918 /* A source of invalid packets is a "double poll" condition,
6919 * where delays cause us to send multiple poll packets. If
6920 * the remote stack receives and processes both polls,
6921 * sequence numbers can wrap around in such a way that a
6922 * resent frame has a sequence number that looks like new data
6923 * with a sequence gap. This would trigger an erroneous SREJ
6924 * request.
6925 *
6926 * Fortunately, this is impossible with a tx window that's
6927 * less than half of the maximum sequence number, which allows
6928 * invalid frames to be safely ignored.
6929 *
6930 * With tx window sizes greater than half of the tx window
6931 * maximum, the frame is invalid and cannot be ignored. This
6932 * causes a disconnect.
6933 */
6934
6935 if (chan->tx_win <= ((chan->tx_win_max + 1) >> 1)) {
6936 BT_DBG("Invalid/Ignore - txseq outside tx window");
6937 return L2CAP_TXSEQ_INVALID_IGNORE;
6938 } else {
6939 BT_DBG("Invalid - txseq outside tx window");
6940 return L2CAP_TXSEQ_INVALID;
6941 }
6942 } else {
6943 BT_DBG("Unexpected - txseq indicates missing frames");
6944 return L2CAP_TXSEQ_UNEXPECTED;
6945 }
6946}
6947
6948static int l2cap_rx_state_recv(struct l2cap_chan *chan,
6949 struct l2cap_ctrl *control,
6950 struct sk_buff *skb, u8 event)
6951{
6952 struct l2cap_ctrl local_control;
6953 int err = 0;
6954 bool skb_in_use = false;
6955
6956 BT_DBG("chan %p, control %p, skb %p, event %d", chan, control, skb,
6957 event);
6958
6959 switch (event) {
6960 case L2CAP_EV_RECV_IFRAME:
6961 switch (l2cap_classify_txseq(chan, control->txseq)) {
6962 case L2CAP_TXSEQ_EXPECTED:
6963 l2cap_pass_to_tx(chan, control);
6964
6965 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
6966 BT_DBG("Busy, discarding expected seq %d",
6967 control->txseq);
6968 break;
6969 }
6970
6971 chan->expected_tx_seq = __next_seq(chan,
6972 control->txseq);
6973
6974 chan->buffer_seq = chan->expected_tx_seq;
6975 skb_in_use = true;
6976
6977 /* l2cap_reassemble_sdu may free skb, hence invalidate
6978 * control, so make a copy in advance to use it after
6979 * l2cap_reassemble_sdu returns and to avoid the race
6980 * condition, for example:
6981 *
6982 * The current thread calls:
6983 * l2cap_reassemble_sdu
6984 * chan->ops->recv == l2cap_sock_recv_cb
6985 * __sock_queue_rcv_skb
6986 * Another thread calls:
6987 * bt_sock_recvmsg
6988 * skb_recv_datagram
6989 * skb_free_datagram
6990 * Then the current thread tries to access control, but
6991 * it was freed by skb_free_datagram.
6992 */
6993 local_control = *control;
6994 err = l2cap_reassemble_sdu(chan, skb, control);
6995 if (err)
6996 break;
6997
6998 if (local_control.final) {
6999 if (!test_and_clear_bit(CONN_REJ_ACT,
7000 &chan->conn_state)) {
7001 local_control.final = 0;
7002 l2cap_retransmit_all(chan, &local_control);
7003 l2cap_ertm_send(chan);
7004 }
7005 }
7006
7007 if (!test_bit(CONN_LOCAL_BUSY, &chan->conn_state))
7008 l2cap_send_ack(chan);
7009 break;
7010 case L2CAP_TXSEQ_UNEXPECTED:
7011 l2cap_pass_to_tx(chan, control);
7012
7013 /* Can't issue SREJ frames in the local busy state.
7014 * Drop this frame, it will be seen as missing
7015 * when local busy is exited.
7016 */
7017 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
7018 BT_DBG("Busy, discarding unexpected seq %d",
7019 control->txseq);
7020 break;
7021 }
7022
7023 /* There was a gap in the sequence, so an SREJ
7024 * must be sent for each missing frame. The
7025 * current frame is stored for later use.
7026 */
7027 skb_queue_tail(&chan->srej_q, skb);
7028 skb_in_use = true;
7029 BT_DBG("Queued %p (queue len %d)", skb,
7030 skb_queue_len(&chan->srej_q));
7031
7032 clear_bit(CONN_SREJ_ACT, &chan->conn_state);
7033 l2cap_seq_list_clear(&chan->srej_list);
7034 l2cap_send_srej(chan, control->txseq);
7035
7036 chan->rx_state = L2CAP_RX_STATE_SREJ_SENT;
7037 break;
7038 case L2CAP_TXSEQ_DUPLICATE:
7039 l2cap_pass_to_tx(chan, control);
7040 break;
7041 case L2CAP_TXSEQ_INVALID_IGNORE:
7042 break;
7043 case L2CAP_TXSEQ_INVALID:
7044 default:
7045 l2cap_send_disconn_req(chan, ECONNRESET);
7046 break;
7047 }
7048 break;
7049 case L2CAP_EV_RECV_RR:
7050 l2cap_pass_to_tx(chan, control);
7051 if (control->final) {
7052 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
7053
7054 if (!test_and_clear_bit(CONN_REJ_ACT, &chan->conn_state) &&
7055 !__chan_is_moving(chan)) {
7056 control->final = 0;
7057 l2cap_retransmit_all(chan, control);
7058 }
7059
7060 l2cap_ertm_send(chan);
7061 } else if (control->poll) {
7062 l2cap_send_i_or_rr_or_rnr(chan);
7063 } else {
7064 if (test_and_clear_bit(CONN_REMOTE_BUSY,
7065 &chan->conn_state) &&
7066 chan->unacked_frames)
7067 __set_retrans_timer(chan);
7068
7069 l2cap_ertm_send(chan);
7070 }
7071 break;
7072 case L2CAP_EV_RECV_RNR:
7073 set_bit(CONN_REMOTE_BUSY, &chan->conn_state);
7074 l2cap_pass_to_tx(chan, control);
7075 if (control && control->poll) {
7076 set_bit(CONN_SEND_FBIT, &chan->conn_state);
7077 l2cap_send_rr_or_rnr(chan, 0);
7078 }
7079 __clear_retrans_timer(chan);
7080 l2cap_seq_list_clear(&chan->retrans_list);
7081 break;
7082 case L2CAP_EV_RECV_REJ:
7083 l2cap_handle_rej(chan, control);
7084 break;
7085 case L2CAP_EV_RECV_SREJ:
7086 l2cap_handle_srej(chan, control);
7087 break;
7088 default:
7089 break;
7090 }
7091
7092 if (skb && !skb_in_use) {
7093 BT_DBG("Freeing %p", skb);
7094 kfree_skb(skb);
7095 }
7096
7097 return err;
7098}
7099
7100static int l2cap_rx_state_srej_sent(struct l2cap_chan *chan,
7101 struct l2cap_ctrl *control,
7102 struct sk_buff *skb, u8 event)
7103{
7104 int err = 0;
7105 u16 txseq = control->txseq;
7106 bool skb_in_use = false;
7107
7108 BT_DBG("chan %p, control %p, skb %p, event %d", chan, control, skb,
7109 event);
7110
7111 switch (event) {
7112 case L2CAP_EV_RECV_IFRAME:
7113 switch (l2cap_classify_txseq(chan, txseq)) {
7114 case L2CAP_TXSEQ_EXPECTED:
7115 /* Keep frame for reassembly later */
7116 l2cap_pass_to_tx(chan, control);
7117 skb_queue_tail(&chan->srej_q, skb);
7118 skb_in_use = true;
7119 BT_DBG("Queued %p (queue len %d)", skb,
7120 skb_queue_len(&chan->srej_q));
7121
7122 chan->expected_tx_seq = __next_seq(chan, txseq);
7123 break;
7124 case L2CAP_TXSEQ_EXPECTED_SREJ:
7125 l2cap_seq_list_pop(&chan->srej_list);
7126
7127 l2cap_pass_to_tx(chan, control);
7128 skb_queue_tail(&chan->srej_q, skb);
7129 skb_in_use = true;
7130 BT_DBG("Queued %p (queue len %d)", skb,
7131 skb_queue_len(&chan->srej_q));
7132
7133 err = l2cap_rx_queued_iframes(chan);
7134 if (err)
7135 break;
7136
7137 break;
7138 case L2CAP_TXSEQ_UNEXPECTED:
7139 /* Got a frame that can't be reassembled yet.
7140 * Save it for later, and send SREJs to cover
7141 * the missing frames.
7142 */
7143 skb_queue_tail(&chan->srej_q, skb);
7144 skb_in_use = true;
7145 BT_DBG("Queued %p (queue len %d)", skb,
7146 skb_queue_len(&chan->srej_q));
7147
7148 l2cap_pass_to_tx(chan, control);
7149 l2cap_send_srej(chan, control->txseq);
7150 break;
7151 case L2CAP_TXSEQ_UNEXPECTED_SREJ:
7152 /* This frame was requested with an SREJ, but
7153 * some expected retransmitted frames are
7154 * missing. Request retransmission of missing
7155 * SREJ'd frames.
7156 */
7157 skb_queue_tail(&chan->srej_q, skb);
7158 skb_in_use = true;
7159 BT_DBG("Queued %p (queue len %d)", skb,
7160 skb_queue_len(&chan->srej_q));
7161
7162 l2cap_pass_to_tx(chan, control);
7163 l2cap_send_srej_list(chan, control->txseq);
7164 break;
7165 case L2CAP_TXSEQ_DUPLICATE_SREJ:
7166 /* We've already queued this frame. Drop this copy. */
7167 l2cap_pass_to_tx(chan, control);
7168 break;
7169 case L2CAP_TXSEQ_DUPLICATE:
7170 /* Expecting a later sequence number, so this frame
7171 * was already received. Ignore it completely.
7172 */
7173 break;
7174 case L2CAP_TXSEQ_INVALID_IGNORE:
7175 break;
7176 case L2CAP_TXSEQ_INVALID:
7177 default:
7178 l2cap_send_disconn_req(chan, ECONNRESET);
7179 break;
7180 }
7181 break;
7182 case L2CAP_EV_RECV_RR:
7183 l2cap_pass_to_tx(chan, control);
7184 if (control->final) {
7185 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
7186
7187 if (!test_and_clear_bit(CONN_REJ_ACT,
7188 &chan->conn_state)) {
7189 control->final = 0;
7190 l2cap_retransmit_all(chan, control);
7191 }
7192
7193 l2cap_ertm_send(chan);
7194 } else if (control->poll) {
7195 if (test_and_clear_bit(CONN_REMOTE_BUSY,
7196 &chan->conn_state) &&
7197 chan->unacked_frames) {
7198 __set_retrans_timer(chan);
7199 }
7200
7201 set_bit(CONN_SEND_FBIT, &chan->conn_state);
7202 l2cap_send_srej_tail(chan);
7203 } else {
7204 if (test_and_clear_bit(CONN_REMOTE_BUSY,
7205 &chan->conn_state) &&
7206 chan->unacked_frames)
7207 __set_retrans_timer(chan);
7208
7209 l2cap_send_ack(chan);
7210 }
7211 break;
7212 case L2CAP_EV_RECV_RNR:
7213 set_bit(CONN_REMOTE_BUSY, &chan->conn_state);
7214 l2cap_pass_to_tx(chan, control);
7215 if (control->poll) {
7216 l2cap_send_srej_tail(chan);
7217 } else {
7218 struct l2cap_ctrl rr_control;
7219 memset(&rr_control, 0, sizeof(rr_control));
7220 rr_control.sframe = 1;
7221 rr_control.super = L2CAP_SUPER_RR;
7222 rr_control.reqseq = chan->buffer_seq;
7223 l2cap_send_sframe(chan, &rr_control);
7224 }
7225
7226 break;
7227 case L2CAP_EV_RECV_REJ:
7228 l2cap_handle_rej(chan, control);
7229 break;
7230 case L2CAP_EV_RECV_SREJ:
7231 l2cap_handle_srej(chan, control);
7232 break;
7233 }
7234
7235 if (skb && !skb_in_use) {
7236 BT_DBG("Freeing %p", skb);
7237 kfree_skb(skb);
7238 }
7239
7240 return err;
7241}
7242
7243static int l2cap_finish_move(struct l2cap_chan *chan)
7244{
7245 BT_DBG("chan %p", chan);
7246
7247 chan->rx_state = L2CAP_RX_STATE_RECV;
7248
7249 if (chan->hs_hcon)
7250 chan->conn->mtu = chan->hs_hcon->hdev->block_mtu;
7251 else
7252 chan->conn->mtu = chan->conn->hcon->hdev->acl_mtu;
7253
7254 return l2cap_resegment(chan);
7255}
7256
7257static int l2cap_rx_state_wait_p(struct l2cap_chan *chan,
7258 struct l2cap_ctrl *control,
7259 struct sk_buff *skb, u8 event)
7260{
7261 int err;
7262
7263 BT_DBG("chan %p, control %p, skb %p, event %d", chan, control, skb,
7264 event);
7265
7266 if (!control->poll)
7267 return -EPROTO;
7268
7269 l2cap_process_reqseq(chan, control->reqseq);
7270
7271 if (!skb_queue_empty(&chan->tx_q))
7272 chan->tx_send_head = skb_peek(&chan->tx_q);
7273 else
7274 chan->tx_send_head = NULL;
7275
7276 /* Rewind next_tx_seq to the point expected
7277 * by the receiver.
7278 */
7279 chan->next_tx_seq = control->reqseq;
7280 chan->unacked_frames = 0;
7281
7282 err = l2cap_finish_move(chan);
7283 if (err)
7284 return err;
7285
7286 set_bit(CONN_SEND_FBIT, &chan->conn_state);
7287 l2cap_send_i_or_rr_or_rnr(chan);
7288
7289 if (event == L2CAP_EV_RECV_IFRAME)
7290 return -EPROTO;
7291
7292 return l2cap_rx_state_recv(chan, control, NULL, event);
7293}
7294
7295static int l2cap_rx_state_wait_f(struct l2cap_chan *chan,
7296 struct l2cap_ctrl *control,
7297 struct sk_buff *skb, u8 event)
7298{
7299 int err;
7300
7301 if (!control->final)
7302 return -EPROTO;
7303
7304 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
7305
7306 chan->rx_state = L2CAP_RX_STATE_RECV;
7307 l2cap_process_reqseq(chan, control->reqseq);
7308
7309 if (!skb_queue_empty(&chan->tx_q))
7310 chan->tx_send_head = skb_peek(&chan->tx_q);
7311 else
7312 chan->tx_send_head = NULL;
7313
7314 /* Rewind next_tx_seq to the point expected
7315 * by the receiver.
7316 */
7317 chan->next_tx_seq = control->reqseq;
7318 chan->unacked_frames = 0;
7319
7320 if (chan->hs_hcon)
7321 chan->conn->mtu = chan->hs_hcon->hdev->block_mtu;
7322 else
7323 chan->conn->mtu = chan->conn->hcon->hdev->acl_mtu;
7324
7325 err = l2cap_resegment(chan);
7326
7327 if (!err)
7328 err = l2cap_rx_state_recv(chan, control, skb, event);
7329
7330 return err;
7331}
7332
7333static bool __valid_reqseq(struct l2cap_chan *chan, u16 reqseq)
7334{
7335 /* Make sure reqseq is for a packet that has been sent but not acked */
7336 u16 unacked;
7337
7338 unacked = __seq_offset(chan, chan->next_tx_seq, chan->expected_ack_seq);
7339 return __seq_offset(chan, chan->next_tx_seq, reqseq) <= unacked;
7340}
7341
7342static int l2cap_rx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
7343 struct sk_buff *skb, u8 event)
7344{
7345 int err = 0;
7346
7347 BT_DBG("chan %p, control %p, skb %p, event %d, state %d", chan,
7348 control, skb, event, chan->rx_state);
7349
7350 if (__valid_reqseq(chan, control->reqseq)) {
7351 switch (chan->rx_state) {
7352 case L2CAP_RX_STATE_RECV:
7353 err = l2cap_rx_state_recv(chan, control, skb, event);
7354 break;
7355 case L2CAP_RX_STATE_SREJ_SENT:
7356 err = l2cap_rx_state_srej_sent(chan, control, skb,
7357 event);
7358 break;
7359 case L2CAP_RX_STATE_WAIT_P:
7360 err = l2cap_rx_state_wait_p(chan, control, skb, event);
7361 break;
7362 case L2CAP_RX_STATE_WAIT_F:
7363 err = l2cap_rx_state_wait_f(chan, control, skb, event);
7364 break;
7365 default:
7366 /* shut it down */
7367 break;
7368 }
7369 } else {
7370 BT_DBG("Invalid reqseq %d (next_tx_seq %d, expected_ack_seq %d",
7371 control->reqseq, chan->next_tx_seq,
7372 chan->expected_ack_seq);
7373 l2cap_send_disconn_req(chan, ECONNRESET);
7374 }
7375
7376 return err;
7377}
7378
7379static int l2cap_stream_rx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
7380 struct sk_buff *skb)
7381{
7382 /* l2cap_reassemble_sdu may free skb, hence invalidate control, so store
7383 * the txseq field in advance to use it after l2cap_reassemble_sdu
7384 * returns and to avoid the race condition, for example:
7385 *
7386 * The current thread calls:
7387 * l2cap_reassemble_sdu
7388 * chan->ops->recv == l2cap_sock_recv_cb
7389 * __sock_queue_rcv_skb
7390 * Another thread calls:
7391 * bt_sock_recvmsg
7392 * skb_recv_datagram
7393 * skb_free_datagram
7394 * Then the current thread tries to access control, but it was freed by
7395 * skb_free_datagram.
7396 */
7397 u16 txseq = control->txseq;
7398
7399 BT_DBG("chan %p, control %p, skb %p, state %d", chan, control, skb,
7400 chan->rx_state);
7401
7402 if (l2cap_classify_txseq(chan, txseq) == L2CAP_TXSEQ_EXPECTED) {
7403 l2cap_pass_to_tx(chan, control);
7404
7405 BT_DBG("buffer_seq %u->%u", chan->buffer_seq,
7406 __next_seq(chan, chan->buffer_seq));
7407
7408 chan->buffer_seq = __next_seq(chan, chan->buffer_seq);
7409
7410 l2cap_reassemble_sdu(chan, skb, control);
7411 } else {
7412 if (chan->sdu) {
7413 kfree_skb(chan->sdu);
7414 chan->sdu = NULL;
7415 }
7416 chan->sdu_last_frag = NULL;
7417 chan->sdu_len = 0;
7418
7419 if (skb) {
7420 BT_DBG("Freeing %p", skb);
7421 kfree_skb(skb);
7422 }
7423 }
7424
7425 chan->last_acked_seq = txseq;
7426 chan->expected_tx_seq = __next_seq(chan, txseq);
7427
7428 return 0;
7429}
7430
7431static int l2cap_data_rcv(struct l2cap_chan *chan, struct sk_buff *skb)
7432{
7433 struct l2cap_ctrl *control = &bt_cb(skb)->l2cap;
7434 u16 len;
7435 u8 event;
7436
7437 __unpack_control(chan, skb);
7438
7439 len = skb->len;
7440
7441 /*
7442 * We can just drop the corrupted I-frame here.
7443 * Receiver will miss it and start proper recovery
7444 * procedures and ask for retransmission.
7445 */
7446 if (l2cap_check_fcs(chan, skb))
7447 goto drop;
7448
7449 if (!control->sframe && control->sar == L2CAP_SAR_START)
7450 len -= L2CAP_SDULEN_SIZE;
7451
7452 if (chan->fcs == L2CAP_FCS_CRC16)
7453 len -= L2CAP_FCS_SIZE;
7454
7455 if (len > chan->mps) {
7456 l2cap_send_disconn_req(chan, ECONNRESET);
7457 goto drop;
7458 }
7459
7460 if (chan->ops->filter) {
7461 if (chan->ops->filter(chan, skb))
7462 goto drop;
7463 }
7464
7465 if (!control->sframe) {
7466 int err;
7467
7468 BT_DBG("iframe sar %d, reqseq %d, final %d, txseq %d",
7469 control->sar, control->reqseq, control->final,
7470 control->txseq);
7471
7472 /* Validate F-bit - F=0 always valid, F=1 only
7473 * valid in TX WAIT_F
7474 */
7475 if (control->final && chan->tx_state != L2CAP_TX_STATE_WAIT_F)
7476 goto drop;
7477
7478 if (chan->mode != L2CAP_MODE_STREAMING) {
7479 event = L2CAP_EV_RECV_IFRAME;
7480 err = l2cap_rx(chan, control, skb, event);
7481 } else {
7482 err = l2cap_stream_rx(chan, control, skb);
7483 }
7484
7485 if (err)
7486 l2cap_send_disconn_req(chan, ECONNRESET);
7487 } else {
7488 const u8 rx_func_to_event[4] = {
7489 L2CAP_EV_RECV_RR, L2CAP_EV_RECV_REJ,
7490 L2CAP_EV_RECV_RNR, L2CAP_EV_RECV_SREJ
7491 };
7492
7493 /* Only I-frames are expected in streaming mode */
7494 if (chan->mode == L2CAP_MODE_STREAMING)
7495 goto drop;
7496
7497 BT_DBG("sframe reqseq %d, final %d, poll %d, super %d",
7498 control->reqseq, control->final, control->poll,
7499 control->super);
7500
7501 if (len != 0) {
7502 BT_ERR("Trailing bytes: %d in sframe", len);
7503 l2cap_send_disconn_req(chan, ECONNRESET);
7504 goto drop;
7505 }
7506
7507 /* Validate F and P bits */
7508 if (control->final && (control->poll ||
7509 chan->tx_state != L2CAP_TX_STATE_WAIT_F))
7510 goto drop;
7511
7512 event = rx_func_to_event[control->super];
7513 if (l2cap_rx(chan, control, skb, event))
7514 l2cap_send_disconn_req(chan, ECONNRESET);
7515 }
7516
7517 return 0;
7518
7519drop:
7520 kfree_skb(skb);
7521 return 0;
7522}
7523
7524static void l2cap_chan_le_send_credits(struct l2cap_chan *chan)
7525{
7526 struct l2cap_conn *conn = chan->conn;
7527 struct l2cap_le_credits pkt;
7528 u16 return_credits;
7529
7530 return_credits = (chan->imtu / chan->mps) + 1;
7531
7532 if (chan->rx_credits >= return_credits)
7533 return;
7534
7535 return_credits -= chan->rx_credits;
7536
7537 BT_DBG("chan %p returning %u credits to sender", chan, return_credits);
7538
7539 chan->rx_credits += return_credits;
7540
7541 pkt.cid = cpu_to_le16(chan->scid);
7542 pkt.credits = cpu_to_le16(return_credits);
7543
7544 chan->ident = l2cap_get_ident(conn);
7545
7546 l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CREDITS, sizeof(pkt), &pkt);
7547}
7548
7549static int l2cap_ecred_recv(struct l2cap_chan *chan, struct sk_buff *skb)
7550{
7551 int err;
7552
7553 BT_DBG("SDU reassemble complete: chan %p skb->len %u", chan, skb->len);
7554
7555 /* Wait recv to confirm reception before updating the credits */
7556 err = chan->ops->recv(chan, skb);
7557
7558 /* Update credits whenever an SDU is received */
7559 l2cap_chan_le_send_credits(chan);
7560
7561 return err;
7562}
7563
7564static int l2cap_ecred_data_rcv(struct l2cap_chan *chan, struct sk_buff *skb)
7565{
7566 int err;
7567
7568 if (!chan->rx_credits) {
7569 BT_ERR("No credits to receive LE L2CAP data");
7570 l2cap_send_disconn_req(chan, ECONNRESET);
7571 return -ENOBUFS;
7572 }
7573
7574 if (chan->imtu < skb->len) {
7575 BT_ERR("Too big LE L2CAP PDU");
7576 return -ENOBUFS;
7577 }
7578
7579 chan->rx_credits--;
7580 BT_DBG("rx_credits %u -> %u", chan->rx_credits + 1, chan->rx_credits);
7581
7582 /* Update if remote had run out of credits, this should only happens
7583 * if the remote is not using the entire MPS.
7584 */
7585 if (!chan->rx_credits)
7586 l2cap_chan_le_send_credits(chan);
7587
7588 err = 0;
7589
7590 if (!chan->sdu) {
7591 u16 sdu_len;
7592
7593 sdu_len = get_unaligned_le16(skb->data);
7594 skb_pull(skb, L2CAP_SDULEN_SIZE);
7595
7596 BT_DBG("Start of new SDU. sdu_len %u skb->len %u imtu %u",
7597 sdu_len, skb->len, chan->imtu);
7598
7599 if (sdu_len > chan->imtu) {
7600 BT_ERR("Too big LE L2CAP SDU length received");
7601 err = -EMSGSIZE;
7602 goto failed;
7603 }
7604
7605 if (skb->len > sdu_len) {
7606 BT_ERR("Too much LE L2CAP data received");
7607 err = -EINVAL;
7608 goto failed;
7609 }
7610
7611 if (skb->len == sdu_len)
7612 return l2cap_ecred_recv(chan, skb);
7613
7614 chan->sdu = skb;
7615 chan->sdu_len = sdu_len;
7616 chan->sdu_last_frag = skb;
7617
7618 /* Detect if remote is not able to use the selected MPS */
7619 if (skb->len + L2CAP_SDULEN_SIZE < chan->mps) {
7620 u16 mps_len = skb->len + L2CAP_SDULEN_SIZE;
7621
7622 /* Adjust the number of credits */
7623 BT_DBG("chan->mps %u -> %u", chan->mps, mps_len);
7624 chan->mps = mps_len;
7625 l2cap_chan_le_send_credits(chan);
7626 }
7627
7628 return 0;
7629 }
7630
7631 BT_DBG("SDU fragment. chan->sdu->len %u skb->len %u chan->sdu_len %u",
7632 chan->sdu->len, skb->len, chan->sdu_len);
7633
7634 if (chan->sdu->len + skb->len > chan->sdu_len) {
7635 BT_ERR("Too much LE L2CAP data received");
7636 err = -EINVAL;
7637 goto failed;
7638 }
7639
7640 append_skb_frag(chan->sdu, skb, &chan->sdu_last_frag);
7641 skb = NULL;
7642
7643 if (chan->sdu->len == chan->sdu_len) {
7644 err = l2cap_ecred_recv(chan, chan->sdu);
7645 if (!err) {
7646 chan->sdu = NULL;
7647 chan->sdu_last_frag = NULL;
7648 chan->sdu_len = 0;
7649 }
7650 }
7651
7652failed:
7653 if (err) {
7654 kfree_skb(skb);
7655 kfree_skb(chan->sdu);
7656 chan->sdu = NULL;
7657 chan->sdu_last_frag = NULL;
7658 chan->sdu_len = 0;
7659 }
7660
7661 /* We can't return an error here since we took care of the skb
7662 * freeing internally. An error return would cause the caller to
7663 * do a double-free of the skb.
7664 */
7665 return 0;
7666}
7667
7668static void l2cap_data_channel(struct l2cap_conn *conn, u16 cid,
7669 struct sk_buff *skb)
7670{
7671 struct l2cap_chan *chan;
7672
7673 chan = l2cap_get_chan_by_scid(conn, cid);
7674 if (!chan) {
7675 if (cid == L2CAP_CID_A2MP) {
7676 chan = a2mp_channel_create(conn, skb);
7677 if (!chan) {
7678 kfree_skb(skb);
7679 return;
7680 }
7681
7682 l2cap_chan_hold(chan);
7683 l2cap_chan_lock(chan);
7684 } else {
7685 BT_DBG("unknown cid 0x%4.4x", cid);
7686 /* Drop packet and return */
7687 kfree_skb(skb);
7688 return;
7689 }
7690 }
7691
7692 BT_DBG("chan %p, len %d", chan, skb->len);
7693
7694 /* If we receive data on a fixed channel before the info req/rsp
7695 * procedure is done simply assume that the channel is supported
7696 * and mark it as ready.
7697 */
7698 if (chan->chan_type == L2CAP_CHAN_FIXED)
7699 l2cap_chan_ready(chan);
7700
7701 if (chan->state != BT_CONNECTED)
7702 goto drop;
7703
7704 switch (chan->mode) {
7705 case L2CAP_MODE_LE_FLOWCTL:
7706 case L2CAP_MODE_EXT_FLOWCTL:
7707 if (l2cap_ecred_data_rcv(chan, skb) < 0)
7708 goto drop;
7709
7710 goto done;
7711
7712 case L2CAP_MODE_BASIC:
7713 /* If socket recv buffers overflows we drop data here
7714 * which is *bad* because L2CAP has to be reliable.
7715 * But we don't have any other choice. L2CAP doesn't
7716 * provide flow control mechanism. */
7717
7718 if (chan->imtu < skb->len) {
7719 BT_ERR("Dropping L2CAP data: receive buffer overflow");
7720 goto drop;
7721 }
7722
7723 if (!chan->ops->recv(chan, skb))
7724 goto done;
7725 break;
7726
7727 case L2CAP_MODE_ERTM:
7728 case L2CAP_MODE_STREAMING:
7729 l2cap_data_rcv(chan, skb);
7730 goto done;
7731
7732 default:
7733 BT_DBG("chan %p: bad mode 0x%2.2x", chan, chan->mode);
7734 break;
7735 }
7736
7737drop:
7738 kfree_skb(skb);
7739
7740done:
7741 l2cap_chan_unlock(chan);
7742 l2cap_chan_put(chan);
7743}
7744
7745static void l2cap_conless_channel(struct l2cap_conn *conn, __le16 psm,
7746 struct sk_buff *skb)
7747{
7748 struct hci_conn *hcon = conn->hcon;
7749 struct l2cap_chan *chan;
7750
7751 if (hcon->type != ACL_LINK)
7752 goto free_skb;
7753
7754 chan = l2cap_global_chan_by_psm(0, psm, &hcon->src, &hcon->dst,
7755 ACL_LINK);
7756 if (!chan)
7757 goto free_skb;
7758
7759 BT_DBG("chan %p, len %d", chan, skb->len);
7760
7761 if (chan->state != BT_BOUND && chan->state != BT_CONNECTED)
7762 goto drop;
7763
7764 if (chan->imtu < skb->len)
7765 goto drop;
7766
7767 /* Store remote BD_ADDR and PSM for msg_name */
7768 bacpy(&bt_cb(skb)->l2cap.bdaddr, &hcon->dst);
7769 bt_cb(skb)->l2cap.psm = psm;
7770
7771 if (!chan->ops->recv(chan, skb)) {
7772 l2cap_chan_put(chan);
7773 return;
7774 }
7775
7776drop:
7777 l2cap_chan_put(chan);
7778free_skb:
7779 kfree_skb(skb);
7780}
7781
7782static void l2cap_recv_frame(struct l2cap_conn *conn, struct sk_buff *skb)
7783{
7784 struct l2cap_hdr *lh = (void *) skb->data;
7785 struct hci_conn *hcon = conn->hcon;
7786 u16 cid, len;
7787 __le16 psm;
7788
7789 if (hcon->state != BT_CONNECTED) {
7790 BT_DBG("queueing pending rx skb");
7791 skb_queue_tail(&conn->pending_rx, skb);
7792 return;
7793 }
7794
7795 skb_pull(skb, L2CAP_HDR_SIZE);
7796 cid = __le16_to_cpu(lh->cid);
7797 len = __le16_to_cpu(lh->len);
7798
7799 if (len != skb->len) {
7800 kfree_skb(skb);
7801 return;
7802 }
7803
7804 /* Since we can't actively block incoming LE connections we must
7805 * at least ensure that we ignore incoming data from them.
7806 */
7807 if (hcon->type == LE_LINK &&
7808 hci_bdaddr_list_lookup(&hcon->hdev->reject_list, &hcon->dst,
7809 bdaddr_dst_type(hcon))) {
7810 kfree_skb(skb);
7811 return;
7812 }
7813
7814 BT_DBG("len %d, cid 0x%4.4x", len, cid);
7815
7816 switch (cid) {
7817 case L2CAP_CID_SIGNALING:
7818 l2cap_sig_channel(conn, skb);
7819 break;
7820
7821 case L2CAP_CID_CONN_LESS:
7822 psm = get_unaligned((__le16 *) skb->data);
7823 skb_pull(skb, L2CAP_PSMLEN_SIZE);
7824 l2cap_conless_channel(conn, psm, skb);
7825 break;
7826
7827 case L2CAP_CID_LE_SIGNALING:
7828 l2cap_le_sig_channel(conn, skb);
7829 break;
7830
7831 default:
7832 l2cap_data_channel(conn, cid, skb);
7833 break;
7834 }
7835}
7836
7837static void process_pending_rx(struct work_struct *work)
7838{
7839 struct l2cap_conn *conn = container_of(work, struct l2cap_conn,
7840 pending_rx_work);
7841 struct sk_buff *skb;
7842
7843 BT_DBG("");
7844
7845 while ((skb = skb_dequeue(&conn->pending_rx)))
7846 l2cap_recv_frame(conn, skb);
7847}
7848
7849static struct l2cap_conn *l2cap_conn_add(struct hci_conn *hcon)
7850{
7851 struct l2cap_conn *conn = hcon->l2cap_data;
7852 struct hci_chan *hchan;
7853
7854 if (conn)
7855 return conn;
7856
7857 hchan = hci_chan_create(hcon);
7858 if (!hchan)
7859 return NULL;
7860
7861 conn = kzalloc(sizeof(*conn), GFP_KERNEL);
7862 if (!conn) {
7863 hci_chan_del(hchan);
7864 return NULL;
7865 }
7866
7867 kref_init(&conn->ref);
7868 hcon->l2cap_data = conn;
7869 conn->hcon = hci_conn_get(hcon);
7870 conn->hchan = hchan;
7871
7872 BT_DBG("hcon %p conn %p hchan %p", hcon, conn, hchan);
7873
7874 switch (hcon->type) {
7875 case LE_LINK:
7876 if (hcon->hdev->le_mtu) {
7877 conn->mtu = hcon->hdev->le_mtu;
7878 break;
7879 }
7880 fallthrough;
7881 default:
7882 conn->mtu = hcon->hdev->acl_mtu;
7883 break;
7884 }
7885
7886 conn->feat_mask = 0;
7887
7888 conn->local_fixed_chan = L2CAP_FC_SIG_BREDR | L2CAP_FC_CONNLESS;
7889
7890 if (hcon->type == ACL_LINK &&
7891 hci_dev_test_flag(hcon->hdev, HCI_HS_ENABLED))
7892 conn->local_fixed_chan |= L2CAP_FC_A2MP;
7893
7894 if (hci_dev_test_flag(hcon->hdev, HCI_LE_ENABLED) &&
7895 (bredr_sc_enabled(hcon->hdev) ||
7896 hci_dev_test_flag(hcon->hdev, HCI_FORCE_BREDR_SMP)))
7897 conn->local_fixed_chan |= L2CAP_FC_SMP_BREDR;
7898
7899 mutex_init(&conn->ident_lock);
7900 mutex_init(&conn->chan_lock);
7901
7902 INIT_LIST_HEAD(&conn->chan_l);
7903 INIT_LIST_HEAD(&conn->users);
7904
7905 INIT_DELAYED_WORK(&conn->info_timer, l2cap_info_timeout);
7906
7907 skb_queue_head_init(&conn->pending_rx);
7908 INIT_WORK(&conn->pending_rx_work, process_pending_rx);
7909 INIT_DELAYED_WORK(&conn->id_addr_timer, l2cap_conn_update_id_addr);
7910
7911 conn->disc_reason = HCI_ERROR_REMOTE_USER_TERM;
7912
7913 return conn;
7914}
7915
7916static bool is_valid_psm(u16 psm, u8 dst_type)
7917{
7918 if (!psm)
7919 return false;
7920
7921 if (bdaddr_type_is_le(dst_type))
7922 return (psm <= 0x00ff);
7923
7924 /* PSM must be odd and lsb of upper byte must be 0 */
7925 return ((psm & 0x0101) == 0x0001);
7926}
7927
7928struct l2cap_chan_data {
7929 struct l2cap_chan *chan;
7930 struct pid *pid;
7931 int count;
7932};
7933
7934static void l2cap_chan_by_pid(struct l2cap_chan *chan, void *data)
7935{
7936 struct l2cap_chan_data *d = data;
7937 struct pid *pid;
7938
7939 if (chan == d->chan)
7940 return;
7941
7942 if (!test_bit(FLAG_DEFER_SETUP, &chan->flags))
7943 return;
7944
7945 pid = chan->ops->get_peer_pid(chan);
7946
7947 /* Only count deferred channels with the same PID/PSM */
7948 if (d->pid != pid || chan->psm != d->chan->psm || chan->ident ||
7949 chan->mode != L2CAP_MODE_EXT_FLOWCTL || chan->state != BT_CONNECT)
7950 return;
7951
7952 d->count++;
7953}
7954
7955int l2cap_chan_connect(struct l2cap_chan *chan, __le16 psm, u16 cid,
7956 bdaddr_t *dst, u8 dst_type)
7957{
7958 struct l2cap_conn *conn;
7959 struct hci_conn *hcon;
7960 struct hci_dev *hdev;
7961 int err;
7962
7963 BT_DBG("%pMR -> %pMR (type %u) psm 0x%4.4x mode 0x%2.2x", &chan->src,
7964 dst, dst_type, __le16_to_cpu(psm), chan->mode);
7965
7966 hdev = hci_get_route(dst, &chan->src, chan->src_type);
7967 if (!hdev)
7968 return -EHOSTUNREACH;
7969
7970 hci_dev_lock(hdev);
7971
7972 if (!is_valid_psm(__le16_to_cpu(psm), dst_type) && !cid &&
7973 chan->chan_type != L2CAP_CHAN_RAW) {
7974 err = -EINVAL;
7975 goto done;
7976 }
7977
7978 if (chan->chan_type == L2CAP_CHAN_CONN_ORIENTED && !psm) {
7979 err = -EINVAL;
7980 goto done;
7981 }
7982
7983 if (chan->chan_type == L2CAP_CHAN_FIXED && !cid) {
7984 err = -EINVAL;
7985 goto done;
7986 }
7987
7988 switch (chan->mode) {
7989 case L2CAP_MODE_BASIC:
7990 break;
7991 case L2CAP_MODE_LE_FLOWCTL:
7992 break;
7993 case L2CAP_MODE_EXT_FLOWCTL:
7994 if (!enable_ecred) {
7995 err = -EOPNOTSUPP;
7996 goto done;
7997 }
7998 break;
7999 case L2CAP_MODE_ERTM:
8000 case L2CAP_MODE_STREAMING:
8001 if (!disable_ertm)
8002 break;
8003 fallthrough;
8004 default:
8005 err = -EOPNOTSUPP;
8006 goto done;
8007 }
8008
8009 switch (chan->state) {
8010 case BT_CONNECT:
8011 case BT_CONNECT2:
8012 case BT_CONFIG:
8013 /* Already connecting */
8014 err = 0;
8015 goto done;
8016
8017 case BT_CONNECTED:
8018 /* Already connected */
8019 err = -EISCONN;
8020 goto done;
8021
8022 case BT_OPEN:
8023 case BT_BOUND:
8024 /* Can connect */
8025 break;
8026
8027 default:
8028 err = -EBADFD;
8029 goto done;
8030 }
8031
8032 /* Set destination address and psm */
8033 bacpy(&chan->dst, dst);
8034 chan->dst_type = dst_type;
8035
8036 chan->psm = psm;
8037 chan->dcid = cid;
8038
8039 if (bdaddr_type_is_le(dst_type)) {
8040 /* Convert from L2CAP channel address type to HCI address type
8041 */
8042 if (dst_type == BDADDR_LE_PUBLIC)
8043 dst_type = ADDR_LE_DEV_PUBLIC;
8044 else
8045 dst_type = ADDR_LE_DEV_RANDOM;
8046
8047 if (hci_dev_test_flag(hdev, HCI_ADVERTISING))
8048 hcon = hci_connect_le(hdev, dst, dst_type, false,
8049 chan->sec_level,
8050 HCI_LE_CONN_TIMEOUT,
8051 HCI_ROLE_SLAVE);
8052 else
8053 hcon = hci_connect_le_scan(hdev, dst, dst_type,
8054 chan->sec_level,
8055 HCI_LE_CONN_TIMEOUT,
8056 CONN_REASON_L2CAP_CHAN);
8057
8058 } else {
8059 u8 auth_type = l2cap_get_auth_type(chan);
8060 hcon = hci_connect_acl(hdev, dst, chan->sec_level, auth_type,
8061 CONN_REASON_L2CAP_CHAN);
8062 }
8063
8064 if (IS_ERR(hcon)) {
8065 err = PTR_ERR(hcon);
8066 goto done;
8067 }
8068
8069 conn = l2cap_conn_add(hcon);
8070 if (!conn) {
8071 hci_conn_drop(hcon);
8072 err = -ENOMEM;
8073 goto done;
8074 }
8075
8076 if (chan->mode == L2CAP_MODE_EXT_FLOWCTL) {
8077 struct l2cap_chan_data data;
8078
8079 data.chan = chan;
8080 data.pid = chan->ops->get_peer_pid(chan);
8081 data.count = 1;
8082
8083 l2cap_chan_list(conn, l2cap_chan_by_pid, &data);
8084
8085 /* Check if there isn't too many channels being connected */
8086 if (data.count > L2CAP_ECRED_CONN_SCID_MAX) {
8087 hci_conn_drop(hcon);
8088 err = -EPROTO;
8089 goto done;
8090 }
8091 }
8092
8093 mutex_lock(&conn->chan_lock);
8094 l2cap_chan_lock(chan);
8095
8096 if (cid && __l2cap_get_chan_by_dcid(conn, cid)) {
8097 hci_conn_drop(hcon);
8098 err = -EBUSY;
8099 goto chan_unlock;
8100 }
8101
8102 /* Update source addr of the socket */
8103 bacpy(&chan->src, &hcon->src);
8104 chan->src_type = bdaddr_src_type(hcon);
8105
8106 __l2cap_chan_add(conn, chan);
8107
8108 /* l2cap_chan_add takes its own ref so we can drop this one */
8109 hci_conn_drop(hcon);
8110
8111 l2cap_state_change(chan, BT_CONNECT);
8112 __set_chan_timer(chan, chan->ops->get_sndtimeo(chan));
8113
8114 /* Release chan->sport so that it can be reused by other
8115 * sockets (as it's only used for listening sockets).
8116 */
8117 write_lock(&chan_list_lock);
8118 chan->sport = 0;
8119 write_unlock(&chan_list_lock);
8120
8121 if (hcon->state == BT_CONNECTED) {
8122 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) {
8123 __clear_chan_timer(chan);
8124 if (l2cap_chan_check_security(chan, true))
8125 l2cap_state_change(chan, BT_CONNECTED);
8126 } else
8127 l2cap_do_start(chan);
8128 }
8129
8130 err = 0;
8131
8132chan_unlock:
8133 l2cap_chan_unlock(chan);
8134 mutex_unlock(&conn->chan_lock);
8135done:
8136 hci_dev_unlock(hdev);
8137 hci_dev_put(hdev);
8138 return err;
8139}
8140EXPORT_SYMBOL_GPL(l2cap_chan_connect);
8141
8142static void l2cap_ecred_reconfigure(struct l2cap_chan *chan)
8143{
8144 struct l2cap_conn *conn = chan->conn;
8145 struct {
8146 struct l2cap_ecred_reconf_req req;
8147 __le16 scid;
8148 } pdu;
8149
8150 pdu.req.mtu = cpu_to_le16(chan->imtu);
8151 pdu.req.mps = cpu_to_le16(chan->mps);
8152 pdu.scid = cpu_to_le16(chan->scid);
8153
8154 chan->ident = l2cap_get_ident(conn);
8155
8156 l2cap_send_cmd(conn, chan->ident, L2CAP_ECRED_RECONF_REQ,
8157 sizeof(pdu), &pdu);
8158}
8159
8160int l2cap_chan_reconfigure(struct l2cap_chan *chan, __u16 mtu)
8161{
8162 if (chan->imtu > mtu)
8163 return -EINVAL;
8164
8165 BT_DBG("chan %p mtu 0x%4.4x", chan, mtu);
8166
8167 chan->imtu = mtu;
8168
8169 l2cap_ecred_reconfigure(chan);
8170
8171 return 0;
8172}
8173
8174/* ---- L2CAP interface with lower layer (HCI) ---- */
8175
8176int l2cap_connect_ind(struct hci_dev *hdev, bdaddr_t *bdaddr)
8177{
8178 int exact = 0, lm1 = 0, lm2 = 0;
8179 struct l2cap_chan *c;
8180
8181 BT_DBG("hdev %s, bdaddr %pMR", hdev->name, bdaddr);
8182
8183 /* Find listening sockets and check their link_mode */
8184 read_lock(&chan_list_lock);
8185 list_for_each_entry(c, &chan_list, global_l) {
8186 if (c->state != BT_LISTEN)
8187 continue;
8188
8189 if (!bacmp(&c->src, &hdev->bdaddr)) {
8190 lm1 |= HCI_LM_ACCEPT;
8191 if (test_bit(FLAG_ROLE_SWITCH, &c->flags))
8192 lm1 |= HCI_LM_MASTER;
8193 exact++;
8194 } else if (!bacmp(&c->src, BDADDR_ANY)) {
8195 lm2 |= HCI_LM_ACCEPT;
8196 if (test_bit(FLAG_ROLE_SWITCH, &c->flags))
8197 lm2 |= HCI_LM_MASTER;
8198 }
8199 }
8200 read_unlock(&chan_list_lock);
8201
8202 return exact ? lm1 : lm2;
8203}
8204
8205/* Find the next fixed channel in BT_LISTEN state, continue iteration
8206 * from an existing channel in the list or from the beginning of the
8207 * global list (by passing NULL as first parameter).
8208 */
8209static struct l2cap_chan *l2cap_global_fixed_chan(struct l2cap_chan *c,
8210 struct hci_conn *hcon)
8211{
8212 u8 src_type = bdaddr_src_type(hcon);
8213
8214 read_lock(&chan_list_lock);
8215
8216 if (c)
8217 c = list_next_entry(c, global_l);
8218 else
8219 c = list_entry(chan_list.next, typeof(*c), global_l);
8220
8221 list_for_each_entry_from(c, &chan_list, global_l) {
8222 if (c->chan_type != L2CAP_CHAN_FIXED)
8223 continue;
8224 if (c->state != BT_LISTEN)
8225 continue;
8226 if (bacmp(&c->src, &hcon->src) && bacmp(&c->src, BDADDR_ANY))
8227 continue;
8228 if (src_type != c->src_type)
8229 continue;
8230
8231 c = l2cap_chan_hold_unless_zero(c);
8232 read_unlock(&chan_list_lock);
8233 return c;
8234 }
8235
8236 read_unlock(&chan_list_lock);
8237
8238 return NULL;
8239}
8240
8241static void l2cap_connect_cfm(struct hci_conn *hcon, u8 status)
8242{
8243 struct hci_dev *hdev = hcon->hdev;
8244 struct l2cap_conn *conn;
8245 struct l2cap_chan *pchan;
8246 u8 dst_type;
8247
8248 if (hcon->type != ACL_LINK && hcon->type != LE_LINK)
8249 return;
8250
8251 BT_DBG("hcon %p bdaddr %pMR status %d", hcon, &hcon->dst, status);
8252
8253 if (status) {
8254 l2cap_conn_del(hcon, bt_to_errno(status));
8255 return;
8256 }
8257
8258 conn = l2cap_conn_add(hcon);
8259 if (!conn)
8260 return;
8261
8262 dst_type = bdaddr_dst_type(hcon);
8263
8264 /* If device is blocked, do not create channels for it */
8265 if (hci_bdaddr_list_lookup(&hdev->reject_list, &hcon->dst, dst_type))
8266 return;
8267
8268 /* Find fixed channels and notify them of the new connection. We
8269 * use multiple individual lookups, continuing each time where
8270 * we left off, because the list lock would prevent calling the
8271 * potentially sleeping l2cap_chan_lock() function.
8272 */
8273 pchan = l2cap_global_fixed_chan(NULL, hcon);
8274 while (pchan) {
8275 struct l2cap_chan *chan, *next;
8276
8277 /* Client fixed channels should override server ones */
8278 if (__l2cap_get_chan_by_dcid(conn, pchan->scid))
8279 goto next;
8280
8281 l2cap_chan_lock(pchan);
8282 chan = pchan->ops->new_connection(pchan);
8283 if (chan) {
8284 bacpy(&chan->src, &hcon->src);
8285 bacpy(&chan->dst, &hcon->dst);
8286 chan->src_type = bdaddr_src_type(hcon);
8287 chan->dst_type = dst_type;
8288
8289 __l2cap_chan_add(conn, chan);
8290 }
8291
8292 l2cap_chan_unlock(pchan);
8293next:
8294 next = l2cap_global_fixed_chan(pchan, hcon);
8295 l2cap_chan_put(pchan);
8296 pchan = next;
8297 }
8298
8299 l2cap_conn_ready(conn);
8300}
8301
8302int l2cap_disconn_ind(struct hci_conn *hcon)
8303{
8304 struct l2cap_conn *conn = hcon->l2cap_data;
8305
8306 BT_DBG("hcon %p", hcon);
8307
8308 if (!conn)
8309 return HCI_ERROR_REMOTE_USER_TERM;
8310 return conn->disc_reason;
8311}
8312
8313static void l2cap_disconn_cfm(struct hci_conn *hcon, u8 reason)
8314{
8315 if (hcon->type != ACL_LINK && hcon->type != LE_LINK)
8316 return;
8317
8318 BT_DBG("hcon %p reason %d", hcon, reason);
8319
8320 l2cap_conn_del(hcon, bt_to_errno(reason));
8321}
8322
8323static inline void l2cap_check_encryption(struct l2cap_chan *chan, u8 encrypt)
8324{
8325 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED)
8326 return;
8327
8328 if (encrypt == 0x00) {
8329 if (chan->sec_level == BT_SECURITY_MEDIUM) {
8330 __set_chan_timer(chan, L2CAP_ENC_TIMEOUT);
8331 } else if (chan->sec_level == BT_SECURITY_HIGH ||
8332 chan->sec_level == BT_SECURITY_FIPS)
8333 l2cap_chan_close(chan, ECONNREFUSED);
8334 } else {
8335 if (chan->sec_level == BT_SECURITY_MEDIUM)
8336 __clear_chan_timer(chan);
8337 }
8338}
8339
8340static void l2cap_security_cfm(struct hci_conn *hcon, u8 status, u8 encrypt)
8341{
8342 struct l2cap_conn *conn = hcon->l2cap_data;
8343 struct l2cap_chan *chan;
8344
8345 if (!conn)
8346 return;
8347
8348 BT_DBG("conn %p status 0x%2.2x encrypt %u", conn, status, encrypt);
8349
8350 mutex_lock(&conn->chan_lock);
8351
8352 list_for_each_entry(chan, &conn->chan_l, list) {
8353 l2cap_chan_lock(chan);
8354
8355 BT_DBG("chan %p scid 0x%4.4x state %s", chan, chan->scid,
8356 state_to_string(chan->state));
8357
8358 if (chan->scid == L2CAP_CID_A2MP) {
8359 l2cap_chan_unlock(chan);
8360 continue;
8361 }
8362
8363 if (!status && encrypt)
8364 chan->sec_level = hcon->sec_level;
8365
8366 if (!__l2cap_no_conn_pending(chan)) {
8367 l2cap_chan_unlock(chan);
8368 continue;
8369 }
8370
8371 if (!status && (chan->state == BT_CONNECTED ||
8372 chan->state == BT_CONFIG)) {
8373 chan->ops->resume(chan);
8374 l2cap_check_encryption(chan, encrypt);
8375 l2cap_chan_unlock(chan);
8376 continue;
8377 }
8378
8379 if (chan->state == BT_CONNECT) {
8380 if (!status && l2cap_check_enc_key_size(hcon))
8381 l2cap_start_connection(chan);
8382 else
8383 __set_chan_timer(chan, L2CAP_DISC_TIMEOUT);
8384 } else if (chan->state == BT_CONNECT2 &&
8385 !(chan->mode == L2CAP_MODE_EXT_FLOWCTL ||
8386 chan->mode == L2CAP_MODE_LE_FLOWCTL)) {
8387 struct l2cap_conn_rsp rsp;
8388 __u16 res, stat;
8389
8390 if (!status && l2cap_check_enc_key_size(hcon)) {
8391 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) {
8392 res = L2CAP_CR_PEND;
8393 stat = L2CAP_CS_AUTHOR_PEND;
8394 chan->ops->defer(chan);
8395 } else {
8396 l2cap_state_change(chan, BT_CONFIG);
8397 res = L2CAP_CR_SUCCESS;
8398 stat = L2CAP_CS_NO_INFO;
8399 }
8400 } else {
8401 l2cap_state_change(chan, BT_DISCONN);
8402 __set_chan_timer(chan, L2CAP_DISC_TIMEOUT);
8403 res = L2CAP_CR_SEC_BLOCK;
8404 stat = L2CAP_CS_NO_INFO;
8405 }
8406
8407 rsp.scid = cpu_to_le16(chan->dcid);
8408 rsp.dcid = cpu_to_le16(chan->scid);
8409 rsp.result = cpu_to_le16(res);
8410 rsp.status = cpu_to_le16(stat);
8411 l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_RSP,
8412 sizeof(rsp), &rsp);
8413
8414 if (!test_bit(CONF_REQ_SENT, &chan->conf_state) &&
8415 res == L2CAP_CR_SUCCESS) {
8416 char buf[128];
8417 set_bit(CONF_REQ_SENT, &chan->conf_state);
8418 l2cap_send_cmd(conn, l2cap_get_ident(conn),
8419 L2CAP_CONF_REQ,
8420 l2cap_build_conf_req(chan, buf, sizeof(buf)),
8421 buf);
8422 chan->num_conf_req++;
8423 }
8424 }
8425
8426 l2cap_chan_unlock(chan);
8427 }
8428
8429 mutex_unlock(&conn->chan_lock);
8430}
8431
8432/* Append fragment into frame respecting the maximum len of rx_skb */
8433static int l2cap_recv_frag(struct l2cap_conn *conn, struct sk_buff *skb,
8434 u16 len)
8435{
8436 if (!conn->rx_skb) {
8437 /* Allocate skb for the complete frame (with header) */
8438 conn->rx_skb = bt_skb_alloc(len, GFP_KERNEL);
8439 if (!conn->rx_skb)
8440 return -ENOMEM;
8441 /* Init rx_len */
8442 conn->rx_len = len;
8443 }
8444
8445 /* Copy as much as the rx_skb can hold */
8446 len = min_t(u16, len, skb->len);
8447 skb_copy_from_linear_data(skb, skb_put(conn->rx_skb, len), len);
8448 skb_pull(skb, len);
8449 conn->rx_len -= len;
8450
8451 return len;
8452}
8453
8454static int l2cap_recv_len(struct l2cap_conn *conn, struct sk_buff *skb)
8455{
8456 struct sk_buff *rx_skb;
8457 int len;
8458
8459 /* Append just enough to complete the header */
8460 len = l2cap_recv_frag(conn, skb, L2CAP_LEN_SIZE - conn->rx_skb->len);
8461
8462 /* If header could not be read just continue */
8463 if (len < 0 || conn->rx_skb->len < L2CAP_LEN_SIZE)
8464 return len;
8465
8466 rx_skb = conn->rx_skb;
8467 len = get_unaligned_le16(rx_skb->data);
8468
8469 /* Check if rx_skb has enough space to received all fragments */
8470 if (len + (L2CAP_HDR_SIZE - L2CAP_LEN_SIZE) <= skb_tailroom(rx_skb)) {
8471 /* Update expected len */
8472 conn->rx_len = len + (L2CAP_HDR_SIZE - L2CAP_LEN_SIZE);
8473 return L2CAP_LEN_SIZE;
8474 }
8475
8476 /* Reset conn->rx_skb since it will need to be reallocated in order to
8477 * fit all fragments.
8478 */
8479 conn->rx_skb = NULL;
8480
8481 /* Reallocates rx_skb using the exact expected length */
8482 len = l2cap_recv_frag(conn, rx_skb,
8483 len + (L2CAP_HDR_SIZE - L2CAP_LEN_SIZE));
8484 kfree_skb(rx_skb);
8485
8486 return len;
8487}
8488
8489static void l2cap_recv_reset(struct l2cap_conn *conn)
8490{
8491 kfree_skb(conn->rx_skb);
8492 conn->rx_skb = NULL;
8493 conn->rx_len = 0;
8494}
8495
8496void l2cap_recv_acldata(struct hci_conn *hcon, struct sk_buff *skb, u16 flags)
8497{
8498 struct l2cap_conn *conn = hcon->l2cap_data;
8499 int len;
8500
8501 /* For AMP controller do not create l2cap conn */
8502 if (!conn && hcon->hdev->dev_type != HCI_PRIMARY)
8503 goto drop;
8504
8505 if (!conn)
8506 conn = l2cap_conn_add(hcon);
8507
8508 if (!conn)
8509 goto drop;
8510
8511 BT_DBG("conn %p len %u flags 0x%x", conn, skb->len, flags);
8512
8513 switch (flags) {
8514 case ACL_START:
8515 case ACL_START_NO_FLUSH:
8516 case ACL_COMPLETE:
8517 if (conn->rx_skb) {
8518 BT_ERR("Unexpected start frame (len %d)", skb->len);
8519 l2cap_recv_reset(conn);
8520 l2cap_conn_unreliable(conn, ECOMM);
8521 }
8522
8523 /* Start fragment may not contain the L2CAP length so just
8524 * copy the initial byte when that happens and use conn->mtu as
8525 * expected length.
8526 */
8527 if (skb->len < L2CAP_LEN_SIZE) {
8528 l2cap_recv_frag(conn, skb, conn->mtu);
8529 break;
8530 }
8531
8532 len = get_unaligned_le16(skb->data) + L2CAP_HDR_SIZE;
8533
8534 if (len == skb->len) {
8535 /* Complete frame received */
8536 l2cap_recv_frame(conn, skb);
8537 return;
8538 }
8539
8540 BT_DBG("Start: total len %d, frag len %u", len, skb->len);
8541
8542 if (skb->len > len) {
8543 BT_ERR("Frame is too long (len %u, expected len %d)",
8544 skb->len, len);
8545 l2cap_conn_unreliable(conn, ECOMM);
8546 goto drop;
8547 }
8548
8549 /* Append fragment into frame (with header) */
8550 if (l2cap_recv_frag(conn, skb, len) < 0)
8551 goto drop;
8552
8553 break;
8554
8555 case ACL_CONT:
8556 BT_DBG("Cont: frag len %u (expecting %u)", skb->len, conn->rx_len);
8557
8558 if (!conn->rx_skb) {
8559 BT_ERR("Unexpected continuation frame (len %d)", skb->len);
8560 l2cap_conn_unreliable(conn, ECOMM);
8561 goto drop;
8562 }
8563
8564 /* Complete the L2CAP length if it has not been read */
8565 if (conn->rx_skb->len < L2CAP_LEN_SIZE) {
8566 if (l2cap_recv_len(conn, skb) < 0) {
8567 l2cap_conn_unreliable(conn, ECOMM);
8568 goto drop;
8569 }
8570
8571 /* Header still could not be read just continue */
8572 if (conn->rx_skb->len < L2CAP_LEN_SIZE)
8573 break;
8574 }
8575
8576 if (skb->len > conn->rx_len) {
8577 BT_ERR("Fragment is too long (len %u, expected %u)",
8578 skb->len, conn->rx_len);
8579 l2cap_recv_reset(conn);
8580 l2cap_conn_unreliable(conn, ECOMM);
8581 goto drop;
8582 }
8583
8584 /* Append fragment into frame (with header) */
8585 l2cap_recv_frag(conn, skb, skb->len);
8586
8587 if (!conn->rx_len) {
8588 /* Complete frame received. l2cap_recv_frame
8589 * takes ownership of the skb so set the global
8590 * rx_skb pointer to NULL first.
8591 */
8592 struct sk_buff *rx_skb = conn->rx_skb;
8593 conn->rx_skb = NULL;
8594 l2cap_recv_frame(conn, rx_skb);
8595 }
8596 break;
8597 }
8598
8599drop:
8600 kfree_skb(skb);
8601}
8602
8603static struct hci_cb l2cap_cb = {
8604 .name = "L2CAP",
8605 .connect_cfm = l2cap_connect_cfm,
8606 .disconn_cfm = l2cap_disconn_cfm,
8607 .security_cfm = l2cap_security_cfm,
8608};
8609
8610static int l2cap_debugfs_show(struct seq_file *f, void *p)
8611{
8612 struct l2cap_chan *c;
8613
8614 read_lock(&chan_list_lock);
8615
8616 list_for_each_entry(c, &chan_list, global_l) {
8617 seq_printf(f, "%pMR (%u) %pMR (%u) %d %d 0x%4.4x 0x%4.4x %d %d %d %d\n",
8618 &c->src, c->src_type, &c->dst, c->dst_type,
8619 c->state, __le16_to_cpu(c->psm),
8620 c->scid, c->dcid, c->imtu, c->omtu,
8621 c->sec_level, c->mode);
8622 }
8623
8624 read_unlock(&chan_list_lock);
8625
8626 return 0;
8627}
8628
8629DEFINE_SHOW_ATTRIBUTE(l2cap_debugfs);
8630
8631static struct dentry *l2cap_debugfs;
8632
8633int __init l2cap_init(void)
8634{
8635 int err;
8636
8637 err = l2cap_init_sockets();
8638 if (err < 0)
8639 return err;
8640
8641 hci_register_cb(&l2cap_cb);
8642
8643 if (IS_ERR_OR_NULL(bt_debugfs))
8644 return 0;
8645
8646 l2cap_debugfs = debugfs_create_file("l2cap", 0444, bt_debugfs,
8647 NULL, &l2cap_debugfs_fops);
8648
8649 return 0;
8650}
8651
8652void l2cap_exit(void)
8653{
8654 debugfs_remove(l2cap_debugfs);
8655 hci_unregister_cb(&l2cap_cb);
8656 l2cap_cleanup_sockets();
8657}
8658
8659module_param(disable_ertm, bool, 0644);
8660MODULE_PARM_DESC(disable_ertm, "Disable enhanced retransmission mode");
8661
8662module_param(enable_ecred, bool, 0644);
8663MODULE_PARM_DESC(enable_ecred, "Enable enhanced credit flow control mode");
1/*
2 BlueZ - Bluetooth protocol stack for Linux
3 Copyright (C) 2000-2001 Qualcomm Incorporated
4 Copyright (C) 2009-2010 Gustavo F. Padovan <gustavo@padovan.org>
5 Copyright (C) 2010 Google Inc.
6 Copyright (C) 2011 ProFUSION Embedded Systems
7 Copyright (c) 2012 Code Aurora Forum. All rights reserved.
8
9 Written 2000,2001 by Maxim Krasnyansky <maxk@qualcomm.com>
10
11 This program is free software; you can redistribute it and/or modify
12 it under the terms of the GNU General Public License version 2 as
13 published by the Free Software Foundation;
14
15 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
16 OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS.
18 IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) AND AUTHOR(S) BE LIABLE FOR ANY
19 CLAIM, OR ANY SPECIAL INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES
20 WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
21 ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
22 OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
23
24 ALL LIABILITY, INCLUDING LIABILITY FOR INFRINGEMENT OF ANY PATENTS,
25 COPYRIGHTS, TRADEMARKS OR OTHER RIGHTS, RELATING TO USE OF THIS
26 SOFTWARE IS DISCLAIMED.
27*/
28
29/* Bluetooth L2CAP core. */
30
31#include <linux/module.h>
32
33#include <linux/types.h>
34#include <linux/capability.h>
35#include <linux/errno.h>
36#include <linux/kernel.h>
37#include <linux/sched.h>
38#include <linux/slab.h>
39#include <linux/poll.h>
40#include <linux/fcntl.h>
41#include <linux/init.h>
42#include <linux/interrupt.h>
43#include <linux/socket.h>
44#include <linux/skbuff.h>
45#include <linux/list.h>
46#include <linux/device.h>
47#include <linux/debugfs.h>
48#include <linux/seq_file.h>
49#include <linux/uaccess.h>
50#include <linux/crc16.h>
51#include <net/sock.h>
52
53#include <asm/unaligned.h>
54
55#include <net/bluetooth/bluetooth.h>
56#include <net/bluetooth/hci_core.h>
57#include <net/bluetooth/l2cap.h>
58#include <net/bluetooth/smp.h>
59
60bool disable_ertm;
61
62static u32 l2cap_feat_mask = L2CAP_FEAT_FIXED_CHAN;
63static u8 l2cap_fixed_chan[8] = { L2CAP_FC_L2CAP, };
64
65static LIST_HEAD(chan_list);
66static DEFINE_RWLOCK(chan_list_lock);
67
68static struct sk_buff *l2cap_build_cmd(struct l2cap_conn *conn,
69 u8 code, u8 ident, u16 dlen, void *data);
70static void l2cap_send_cmd(struct l2cap_conn *conn, u8 ident, u8 code, u16 len,
71 void *data);
72static int l2cap_build_conf_req(struct l2cap_chan *chan, void *data);
73static void l2cap_send_disconn_req(struct l2cap_conn *conn,
74 struct l2cap_chan *chan, int err);
75
76/* ---- L2CAP channels ---- */
77
78static struct l2cap_chan *__l2cap_get_chan_by_dcid(struct l2cap_conn *conn, u16 cid)
79{
80 struct l2cap_chan *c;
81
82 list_for_each_entry(c, &conn->chan_l, list) {
83 if (c->dcid == cid)
84 return c;
85 }
86 return NULL;
87}
88
89static struct l2cap_chan *__l2cap_get_chan_by_scid(struct l2cap_conn *conn, u16 cid)
90{
91 struct l2cap_chan *c;
92
93 list_for_each_entry(c, &conn->chan_l, list) {
94 if (c->scid == cid)
95 return c;
96 }
97 return NULL;
98}
99
100/* Find channel with given SCID.
101 * Returns locked channel. */
102static struct l2cap_chan *l2cap_get_chan_by_scid(struct l2cap_conn *conn, u16 cid)
103{
104 struct l2cap_chan *c;
105
106 mutex_lock(&conn->chan_lock);
107 c = __l2cap_get_chan_by_scid(conn, cid);
108 if (c)
109 l2cap_chan_lock(c);
110 mutex_unlock(&conn->chan_lock);
111
112 return c;
113}
114
115static struct l2cap_chan *__l2cap_get_chan_by_ident(struct l2cap_conn *conn, u8 ident)
116{
117 struct l2cap_chan *c;
118
119 list_for_each_entry(c, &conn->chan_l, list) {
120 if (c->ident == ident)
121 return c;
122 }
123 return NULL;
124}
125
126static struct l2cap_chan *__l2cap_global_chan_by_addr(__le16 psm, bdaddr_t *src)
127{
128 struct l2cap_chan *c;
129
130 list_for_each_entry(c, &chan_list, global_l) {
131 if (c->sport == psm && !bacmp(&bt_sk(c->sk)->src, src))
132 return c;
133 }
134 return NULL;
135}
136
137int l2cap_add_psm(struct l2cap_chan *chan, bdaddr_t *src, __le16 psm)
138{
139 int err;
140
141 write_lock(&chan_list_lock);
142
143 if (psm && __l2cap_global_chan_by_addr(psm, src)) {
144 err = -EADDRINUSE;
145 goto done;
146 }
147
148 if (psm) {
149 chan->psm = psm;
150 chan->sport = psm;
151 err = 0;
152 } else {
153 u16 p;
154
155 err = -EINVAL;
156 for (p = 0x1001; p < 0x1100; p += 2)
157 if (!__l2cap_global_chan_by_addr(cpu_to_le16(p), src)) {
158 chan->psm = cpu_to_le16(p);
159 chan->sport = cpu_to_le16(p);
160 err = 0;
161 break;
162 }
163 }
164
165done:
166 write_unlock(&chan_list_lock);
167 return err;
168}
169
170int l2cap_add_scid(struct l2cap_chan *chan, __u16 scid)
171{
172 write_lock(&chan_list_lock);
173
174 chan->scid = scid;
175
176 write_unlock(&chan_list_lock);
177
178 return 0;
179}
180
181static u16 l2cap_alloc_cid(struct l2cap_conn *conn)
182{
183 u16 cid = L2CAP_CID_DYN_START;
184
185 for (; cid < L2CAP_CID_DYN_END; cid++) {
186 if (!__l2cap_get_chan_by_scid(conn, cid))
187 return cid;
188 }
189
190 return 0;
191}
192
193static void __l2cap_state_change(struct l2cap_chan *chan, int state)
194{
195 BT_DBG("chan %p %s -> %s", chan, state_to_string(chan->state),
196 state_to_string(state));
197
198 chan->state = state;
199 chan->ops->state_change(chan->data, state);
200}
201
202static void l2cap_state_change(struct l2cap_chan *chan, int state)
203{
204 struct sock *sk = chan->sk;
205
206 lock_sock(sk);
207 __l2cap_state_change(chan, state);
208 release_sock(sk);
209}
210
211static inline void __l2cap_chan_set_err(struct l2cap_chan *chan, int err)
212{
213 struct sock *sk = chan->sk;
214
215 sk->sk_err = err;
216}
217
218static inline void l2cap_chan_set_err(struct l2cap_chan *chan, int err)
219{
220 struct sock *sk = chan->sk;
221
222 lock_sock(sk);
223 __l2cap_chan_set_err(chan, err);
224 release_sock(sk);
225}
226
227/* ---- L2CAP sequence number lists ---- */
228
229/* For ERTM, ordered lists of sequence numbers must be tracked for
230 * SREJ requests that are received and for frames that are to be
231 * retransmitted. These seq_list functions implement a singly-linked
232 * list in an array, where membership in the list can also be checked
233 * in constant time. Items can also be added to the tail of the list
234 * and removed from the head in constant time, without further memory
235 * allocs or frees.
236 */
237
238static int l2cap_seq_list_init(struct l2cap_seq_list *seq_list, u16 size)
239{
240 size_t alloc_size, i;
241
242 /* Allocated size is a power of 2 to map sequence numbers
243 * (which may be up to 14 bits) in to a smaller array that is
244 * sized for the negotiated ERTM transmit windows.
245 */
246 alloc_size = roundup_pow_of_two(size);
247
248 seq_list->list = kmalloc(sizeof(u16) * alloc_size, GFP_KERNEL);
249 if (!seq_list->list)
250 return -ENOMEM;
251
252 seq_list->mask = alloc_size - 1;
253 seq_list->head = L2CAP_SEQ_LIST_CLEAR;
254 seq_list->tail = L2CAP_SEQ_LIST_CLEAR;
255 for (i = 0; i < alloc_size; i++)
256 seq_list->list[i] = L2CAP_SEQ_LIST_CLEAR;
257
258 return 0;
259}
260
261static inline void l2cap_seq_list_free(struct l2cap_seq_list *seq_list)
262{
263 kfree(seq_list->list);
264}
265
266static inline bool l2cap_seq_list_contains(struct l2cap_seq_list *seq_list,
267 u16 seq)
268{
269 /* Constant-time check for list membership */
270 return seq_list->list[seq & seq_list->mask] != L2CAP_SEQ_LIST_CLEAR;
271}
272
273static u16 l2cap_seq_list_remove(struct l2cap_seq_list *seq_list, u16 seq)
274{
275 u16 mask = seq_list->mask;
276
277 if (seq_list->head == L2CAP_SEQ_LIST_CLEAR) {
278 /* In case someone tries to pop the head of an empty list */
279 return L2CAP_SEQ_LIST_CLEAR;
280 } else if (seq_list->head == seq) {
281 /* Head can be removed in constant time */
282 seq_list->head = seq_list->list[seq & mask];
283 seq_list->list[seq & mask] = L2CAP_SEQ_LIST_CLEAR;
284
285 if (seq_list->head == L2CAP_SEQ_LIST_TAIL) {
286 seq_list->head = L2CAP_SEQ_LIST_CLEAR;
287 seq_list->tail = L2CAP_SEQ_LIST_CLEAR;
288 }
289 } else {
290 /* Walk the list to find the sequence number */
291 u16 prev = seq_list->head;
292 while (seq_list->list[prev & mask] != seq) {
293 prev = seq_list->list[prev & mask];
294 if (prev == L2CAP_SEQ_LIST_TAIL)
295 return L2CAP_SEQ_LIST_CLEAR;
296 }
297
298 /* Unlink the number from the list and clear it */
299 seq_list->list[prev & mask] = seq_list->list[seq & mask];
300 seq_list->list[seq & mask] = L2CAP_SEQ_LIST_CLEAR;
301 if (seq_list->tail == seq)
302 seq_list->tail = prev;
303 }
304 return seq;
305}
306
307static inline u16 l2cap_seq_list_pop(struct l2cap_seq_list *seq_list)
308{
309 /* Remove the head in constant time */
310 return l2cap_seq_list_remove(seq_list, seq_list->head);
311}
312
313static void l2cap_seq_list_clear(struct l2cap_seq_list *seq_list)
314{
315 u16 i;
316
317 if (seq_list->head == L2CAP_SEQ_LIST_CLEAR)
318 return;
319
320 for (i = 0; i <= seq_list->mask; i++)
321 seq_list->list[i] = L2CAP_SEQ_LIST_CLEAR;
322
323 seq_list->head = L2CAP_SEQ_LIST_CLEAR;
324 seq_list->tail = L2CAP_SEQ_LIST_CLEAR;
325}
326
327static void l2cap_seq_list_append(struct l2cap_seq_list *seq_list, u16 seq)
328{
329 u16 mask = seq_list->mask;
330
331 /* All appends happen in constant time */
332
333 if (seq_list->list[seq & mask] != L2CAP_SEQ_LIST_CLEAR)
334 return;
335
336 if (seq_list->tail == L2CAP_SEQ_LIST_CLEAR)
337 seq_list->head = seq;
338 else
339 seq_list->list[seq_list->tail & mask] = seq;
340
341 seq_list->tail = seq;
342 seq_list->list[seq & mask] = L2CAP_SEQ_LIST_TAIL;
343}
344
345static void l2cap_chan_timeout(struct work_struct *work)
346{
347 struct l2cap_chan *chan = container_of(work, struct l2cap_chan,
348 chan_timer.work);
349 struct l2cap_conn *conn = chan->conn;
350 int reason;
351
352 BT_DBG("chan %p state %s", chan, state_to_string(chan->state));
353
354 mutex_lock(&conn->chan_lock);
355 l2cap_chan_lock(chan);
356
357 if (chan->state == BT_CONNECTED || chan->state == BT_CONFIG)
358 reason = ECONNREFUSED;
359 else if (chan->state == BT_CONNECT &&
360 chan->sec_level != BT_SECURITY_SDP)
361 reason = ECONNREFUSED;
362 else
363 reason = ETIMEDOUT;
364
365 l2cap_chan_close(chan, reason);
366
367 l2cap_chan_unlock(chan);
368
369 chan->ops->close(chan->data);
370 mutex_unlock(&conn->chan_lock);
371
372 l2cap_chan_put(chan);
373}
374
375struct l2cap_chan *l2cap_chan_create(void)
376{
377 struct l2cap_chan *chan;
378
379 chan = kzalloc(sizeof(*chan), GFP_ATOMIC);
380 if (!chan)
381 return NULL;
382
383 mutex_init(&chan->lock);
384
385 write_lock(&chan_list_lock);
386 list_add(&chan->global_l, &chan_list);
387 write_unlock(&chan_list_lock);
388
389 INIT_DELAYED_WORK(&chan->chan_timer, l2cap_chan_timeout);
390
391 chan->state = BT_OPEN;
392
393 atomic_set(&chan->refcnt, 1);
394
395 BT_DBG("chan %p", chan);
396
397 return chan;
398}
399
400void l2cap_chan_destroy(struct l2cap_chan *chan)
401{
402 write_lock(&chan_list_lock);
403 list_del(&chan->global_l);
404 write_unlock(&chan_list_lock);
405
406 l2cap_chan_put(chan);
407}
408
409void l2cap_chan_set_defaults(struct l2cap_chan *chan)
410{
411 chan->fcs = L2CAP_FCS_CRC16;
412 chan->max_tx = L2CAP_DEFAULT_MAX_TX;
413 chan->tx_win = L2CAP_DEFAULT_TX_WINDOW;
414 chan->tx_win_max = L2CAP_DEFAULT_TX_WINDOW;
415 chan->sec_level = BT_SECURITY_LOW;
416
417 set_bit(FLAG_FORCE_ACTIVE, &chan->flags);
418}
419
420static void __l2cap_chan_add(struct l2cap_conn *conn, struct l2cap_chan *chan)
421{
422 BT_DBG("conn %p, psm 0x%2.2x, dcid 0x%4.4x", conn,
423 __le16_to_cpu(chan->psm), chan->dcid);
424
425 conn->disc_reason = HCI_ERROR_REMOTE_USER_TERM;
426
427 chan->conn = conn;
428
429 switch (chan->chan_type) {
430 case L2CAP_CHAN_CONN_ORIENTED:
431 if (conn->hcon->type == LE_LINK) {
432 /* LE connection */
433 chan->omtu = L2CAP_LE_DEFAULT_MTU;
434 chan->scid = L2CAP_CID_LE_DATA;
435 chan->dcid = L2CAP_CID_LE_DATA;
436 } else {
437 /* Alloc CID for connection-oriented socket */
438 chan->scid = l2cap_alloc_cid(conn);
439 chan->omtu = L2CAP_DEFAULT_MTU;
440 }
441 break;
442
443 case L2CAP_CHAN_CONN_LESS:
444 /* Connectionless socket */
445 chan->scid = L2CAP_CID_CONN_LESS;
446 chan->dcid = L2CAP_CID_CONN_LESS;
447 chan->omtu = L2CAP_DEFAULT_MTU;
448 break;
449
450 default:
451 /* Raw socket can send/recv signalling messages only */
452 chan->scid = L2CAP_CID_SIGNALING;
453 chan->dcid = L2CAP_CID_SIGNALING;
454 chan->omtu = L2CAP_DEFAULT_MTU;
455 }
456
457 chan->local_id = L2CAP_BESTEFFORT_ID;
458 chan->local_stype = L2CAP_SERV_BESTEFFORT;
459 chan->local_msdu = L2CAP_DEFAULT_MAX_SDU_SIZE;
460 chan->local_sdu_itime = L2CAP_DEFAULT_SDU_ITIME;
461 chan->local_acc_lat = L2CAP_DEFAULT_ACC_LAT;
462 chan->local_flush_to = L2CAP_DEFAULT_FLUSH_TO;
463
464 l2cap_chan_hold(chan);
465
466 list_add(&chan->list, &conn->chan_l);
467}
468
469static void l2cap_chan_add(struct l2cap_conn *conn, struct l2cap_chan *chan)
470{
471 mutex_lock(&conn->chan_lock);
472 __l2cap_chan_add(conn, chan);
473 mutex_unlock(&conn->chan_lock);
474}
475
476static void l2cap_chan_del(struct l2cap_chan *chan, int err)
477{
478 struct sock *sk = chan->sk;
479 struct l2cap_conn *conn = chan->conn;
480 struct sock *parent = bt_sk(sk)->parent;
481
482 __clear_chan_timer(chan);
483
484 BT_DBG("chan %p, conn %p, err %d", chan, conn, err);
485
486 if (conn) {
487 /* Delete from channel list */
488 list_del(&chan->list);
489
490 l2cap_chan_put(chan);
491
492 chan->conn = NULL;
493 hci_conn_put(conn->hcon);
494 }
495
496 lock_sock(sk);
497
498 __l2cap_state_change(chan, BT_CLOSED);
499 sock_set_flag(sk, SOCK_ZAPPED);
500
501 if (err)
502 __l2cap_chan_set_err(chan, err);
503
504 if (parent) {
505 bt_accept_unlink(sk);
506 parent->sk_data_ready(parent, 0);
507 } else
508 sk->sk_state_change(sk);
509
510 release_sock(sk);
511
512 if (!(test_bit(CONF_OUTPUT_DONE, &chan->conf_state) &&
513 test_bit(CONF_INPUT_DONE, &chan->conf_state)))
514 return;
515
516 skb_queue_purge(&chan->tx_q);
517
518 if (chan->mode == L2CAP_MODE_ERTM) {
519 struct srej_list *l, *tmp;
520
521 __clear_retrans_timer(chan);
522 __clear_monitor_timer(chan);
523 __clear_ack_timer(chan);
524
525 skb_queue_purge(&chan->srej_q);
526
527 l2cap_seq_list_free(&chan->srej_list);
528 l2cap_seq_list_free(&chan->retrans_list);
529 list_for_each_entry_safe(l, tmp, &chan->srej_l, list) {
530 list_del(&l->list);
531 kfree(l);
532 }
533 }
534}
535
536static void l2cap_chan_cleanup_listen(struct sock *parent)
537{
538 struct sock *sk;
539
540 BT_DBG("parent %p", parent);
541
542 /* Close not yet accepted channels */
543 while ((sk = bt_accept_dequeue(parent, NULL))) {
544 struct l2cap_chan *chan = l2cap_pi(sk)->chan;
545
546 l2cap_chan_lock(chan);
547 __clear_chan_timer(chan);
548 l2cap_chan_close(chan, ECONNRESET);
549 l2cap_chan_unlock(chan);
550
551 chan->ops->close(chan->data);
552 }
553}
554
555void l2cap_chan_close(struct l2cap_chan *chan, int reason)
556{
557 struct l2cap_conn *conn = chan->conn;
558 struct sock *sk = chan->sk;
559
560 BT_DBG("chan %p state %s sk %p", chan,
561 state_to_string(chan->state), sk);
562
563 switch (chan->state) {
564 case BT_LISTEN:
565 lock_sock(sk);
566 l2cap_chan_cleanup_listen(sk);
567
568 __l2cap_state_change(chan, BT_CLOSED);
569 sock_set_flag(sk, SOCK_ZAPPED);
570 release_sock(sk);
571 break;
572
573 case BT_CONNECTED:
574 case BT_CONFIG:
575 if (chan->chan_type == L2CAP_CHAN_CONN_ORIENTED &&
576 conn->hcon->type == ACL_LINK) {
577 __set_chan_timer(chan, sk->sk_sndtimeo);
578 l2cap_send_disconn_req(conn, chan, reason);
579 } else
580 l2cap_chan_del(chan, reason);
581 break;
582
583 case BT_CONNECT2:
584 if (chan->chan_type == L2CAP_CHAN_CONN_ORIENTED &&
585 conn->hcon->type == ACL_LINK) {
586 struct l2cap_conn_rsp rsp;
587 __u16 result;
588
589 if (test_bit(BT_SK_DEFER_SETUP, &bt_sk(sk)->flags))
590 result = L2CAP_CR_SEC_BLOCK;
591 else
592 result = L2CAP_CR_BAD_PSM;
593 l2cap_state_change(chan, BT_DISCONN);
594
595 rsp.scid = cpu_to_le16(chan->dcid);
596 rsp.dcid = cpu_to_le16(chan->scid);
597 rsp.result = cpu_to_le16(result);
598 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
599 l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_RSP,
600 sizeof(rsp), &rsp);
601 }
602
603 l2cap_chan_del(chan, reason);
604 break;
605
606 case BT_CONNECT:
607 case BT_DISCONN:
608 l2cap_chan_del(chan, reason);
609 break;
610
611 default:
612 lock_sock(sk);
613 sock_set_flag(sk, SOCK_ZAPPED);
614 release_sock(sk);
615 break;
616 }
617}
618
619static inline u8 l2cap_get_auth_type(struct l2cap_chan *chan)
620{
621 if (chan->chan_type == L2CAP_CHAN_RAW) {
622 switch (chan->sec_level) {
623 case BT_SECURITY_HIGH:
624 return HCI_AT_DEDICATED_BONDING_MITM;
625 case BT_SECURITY_MEDIUM:
626 return HCI_AT_DEDICATED_BONDING;
627 default:
628 return HCI_AT_NO_BONDING;
629 }
630 } else if (chan->psm == cpu_to_le16(0x0001)) {
631 if (chan->sec_level == BT_SECURITY_LOW)
632 chan->sec_level = BT_SECURITY_SDP;
633
634 if (chan->sec_level == BT_SECURITY_HIGH)
635 return HCI_AT_NO_BONDING_MITM;
636 else
637 return HCI_AT_NO_BONDING;
638 } else {
639 switch (chan->sec_level) {
640 case BT_SECURITY_HIGH:
641 return HCI_AT_GENERAL_BONDING_MITM;
642 case BT_SECURITY_MEDIUM:
643 return HCI_AT_GENERAL_BONDING;
644 default:
645 return HCI_AT_NO_BONDING;
646 }
647 }
648}
649
650/* Service level security */
651int l2cap_chan_check_security(struct l2cap_chan *chan)
652{
653 struct l2cap_conn *conn = chan->conn;
654 __u8 auth_type;
655
656 auth_type = l2cap_get_auth_type(chan);
657
658 return hci_conn_security(conn->hcon, chan->sec_level, auth_type);
659}
660
661static u8 l2cap_get_ident(struct l2cap_conn *conn)
662{
663 u8 id;
664
665 /* Get next available identificator.
666 * 1 - 128 are used by kernel.
667 * 129 - 199 are reserved.
668 * 200 - 254 are used by utilities like l2ping, etc.
669 */
670
671 spin_lock(&conn->lock);
672
673 if (++conn->tx_ident > 128)
674 conn->tx_ident = 1;
675
676 id = conn->tx_ident;
677
678 spin_unlock(&conn->lock);
679
680 return id;
681}
682
683static void l2cap_send_cmd(struct l2cap_conn *conn, u8 ident, u8 code, u16 len, void *data)
684{
685 struct sk_buff *skb = l2cap_build_cmd(conn, code, ident, len, data);
686 u8 flags;
687
688 BT_DBG("code 0x%2.2x", code);
689
690 if (!skb)
691 return;
692
693 if (lmp_no_flush_capable(conn->hcon->hdev))
694 flags = ACL_START_NO_FLUSH;
695 else
696 flags = ACL_START;
697
698 bt_cb(skb)->force_active = BT_POWER_FORCE_ACTIVE_ON;
699 skb->priority = HCI_PRIO_MAX;
700
701 hci_send_acl(conn->hchan, skb, flags);
702}
703
704static void l2cap_do_send(struct l2cap_chan *chan, struct sk_buff *skb)
705{
706 struct hci_conn *hcon = chan->conn->hcon;
707 u16 flags;
708
709 BT_DBG("chan %p, skb %p len %d priority %u", chan, skb, skb->len,
710 skb->priority);
711
712 if (!test_bit(FLAG_FLUSHABLE, &chan->flags) &&
713 lmp_no_flush_capable(hcon->hdev))
714 flags = ACL_START_NO_FLUSH;
715 else
716 flags = ACL_START;
717
718 bt_cb(skb)->force_active = test_bit(FLAG_FORCE_ACTIVE, &chan->flags);
719 hci_send_acl(chan->conn->hchan, skb, flags);
720}
721
722static void __unpack_enhanced_control(u16 enh, struct l2cap_ctrl *control)
723{
724 control->reqseq = (enh & L2CAP_CTRL_REQSEQ) >> L2CAP_CTRL_REQSEQ_SHIFT;
725 control->final = (enh & L2CAP_CTRL_FINAL) >> L2CAP_CTRL_FINAL_SHIFT;
726
727 if (enh & L2CAP_CTRL_FRAME_TYPE) {
728 /* S-Frame */
729 control->sframe = 1;
730 control->poll = (enh & L2CAP_CTRL_POLL) >> L2CAP_CTRL_POLL_SHIFT;
731 control->super = (enh & L2CAP_CTRL_SUPERVISE) >> L2CAP_CTRL_SUPER_SHIFT;
732
733 control->sar = 0;
734 control->txseq = 0;
735 } else {
736 /* I-Frame */
737 control->sframe = 0;
738 control->sar = (enh & L2CAP_CTRL_SAR) >> L2CAP_CTRL_SAR_SHIFT;
739 control->txseq = (enh & L2CAP_CTRL_TXSEQ) >> L2CAP_CTRL_TXSEQ_SHIFT;
740
741 control->poll = 0;
742 control->super = 0;
743 }
744}
745
746static void __unpack_extended_control(u32 ext, struct l2cap_ctrl *control)
747{
748 control->reqseq = (ext & L2CAP_EXT_CTRL_REQSEQ) >> L2CAP_EXT_CTRL_REQSEQ_SHIFT;
749 control->final = (ext & L2CAP_EXT_CTRL_FINAL) >> L2CAP_EXT_CTRL_FINAL_SHIFT;
750
751 if (ext & L2CAP_EXT_CTRL_FRAME_TYPE) {
752 /* S-Frame */
753 control->sframe = 1;
754 control->poll = (ext & L2CAP_EXT_CTRL_POLL) >> L2CAP_EXT_CTRL_POLL_SHIFT;
755 control->super = (ext & L2CAP_EXT_CTRL_SUPERVISE) >> L2CAP_EXT_CTRL_SUPER_SHIFT;
756
757 control->sar = 0;
758 control->txseq = 0;
759 } else {
760 /* I-Frame */
761 control->sframe = 0;
762 control->sar = (ext & L2CAP_EXT_CTRL_SAR) >> L2CAP_EXT_CTRL_SAR_SHIFT;
763 control->txseq = (ext & L2CAP_EXT_CTRL_TXSEQ) >> L2CAP_EXT_CTRL_TXSEQ_SHIFT;
764
765 control->poll = 0;
766 control->super = 0;
767 }
768}
769
770static inline void __unpack_control(struct l2cap_chan *chan,
771 struct sk_buff *skb)
772{
773 if (test_bit(FLAG_EXT_CTRL, &chan->flags)) {
774 __unpack_extended_control(get_unaligned_le32(skb->data),
775 &bt_cb(skb)->control);
776 } else {
777 __unpack_enhanced_control(get_unaligned_le16(skb->data),
778 &bt_cb(skb)->control);
779 }
780}
781
782static u32 __pack_extended_control(struct l2cap_ctrl *control)
783{
784 u32 packed;
785
786 packed = control->reqseq << L2CAP_EXT_CTRL_REQSEQ_SHIFT;
787 packed |= control->final << L2CAP_EXT_CTRL_FINAL_SHIFT;
788
789 if (control->sframe) {
790 packed |= control->poll << L2CAP_EXT_CTRL_POLL_SHIFT;
791 packed |= control->super << L2CAP_EXT_CTRL_SUPER_SHIFT;
792 packed |= L2CAP_EXT_CTRL_FRAME_TYPE;
793 } else {
794 packed |= control->sar << L2CAP_EXT_CTRL_SAR_SHIFT;
795 packed |= control->txseq << L2CAP_EXT_CTRL_TXSEQ_SHIFT;
796 }
797
798 return packed;
799}
800
801static u16 __pack_enhanced_control(struct l2cap_ctrl *control)
802{
803 u16 packed;
804
805 packed = control->reqseq << L2CAP_CTRL_REQSEQ_SHIFT;
806 packed |= control->final << L2CAP_CTRL_FINAL_SHIFT;
807
808 if (control->sframe) {
809 packed |= control->poll << L2CAP_CTRL_POLL_SHIFT;
810 packed |= control->super << L2CAP_CTRL_SUPER_SHIFT;
811 packed |= L2CAP_CTRL_FRAME_TYPE;
812 } else {
813 packed |= control->sar << L2CAP_CTRL_SAR_SHIFT;
814 packed |= control->txseq << L2CAP_CTRL_TXSEQ_SHIFT;
815 }
816
817 return packed;
818}
819
820static inline void __pack_control(struct l2cap_chan *chan,
821 struct l2cap_ctrl *control,
822 struct sk_buff *skb)
823{
824 if (test_bit(FLAG_EXT_CTRL, &chan->flags)) {
825 put_unaligned_le32(__pack_extended_control(control),
826 skb->data + L2CAP_HDR_SIZE);
827 } else {
828 put_unaligned_le16(__pack_enhanced_control(control),
829 skb->data + L2CAP_HDR_SIZE);
830 }
831}
832
833static inline void l2cap_send_sframe(struct l2cap_chan *chan, u32 control)
834{
835 struct sk_buff *skb;
836 struct l2cap_hdr *lh;
837 struct l2cap_conn *conn = chan->conn;
838 int count, hlen;
839
840 if (chan->state != BT_CONNECTED)
841 return;
842
843 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
844 hlen = L2CAP_EXT_HDR_SIZE;
845 else
846 hlen = L2CAP_ENH_HDR_SIZE;
847
848 if (chan->fcs == L2CAP_FCS_CRC16)
849 hlen += L2CAP_FCS_SIZE;
850
851 BT_DBG("chan %p, control 0x%8.8x", chan, control);
852
853 count = min_t(unsigned int, conn->mtu, hlen);
854
855 control |= __set_sframe(chan);
856
857 if (test_and_clear_bit(CONN_SEND_FBIT, &chan->conn_state))
858 control |= __set_ctrl_final(chan);
859
860 if (test_and_clear_bit(CONN_SEND_PBIT, &chan->conn_state))
861 control |= __set_ctrl_poll(chan);
862
863 skb = bt_skb_alloc(count, GFP_ATOMIC);
864 if (!skb)
865 return;
866
867 lh = (struct l2cap_hdr *) skb_put(skb, L2CAP_HDR_SIZE);
868 lh->len = cpu_to_le16(hlen - L2CAP_HDR_SIZE);
869 lh->cid = cpu_to_le16(chan->dcid);
870
871 __put_control(chan, control, skb_put(skb, __ctrl_size(chan)));
872
873 if (chan->fcs == L2CAP_FCS_CRC16) {
874 u16 fcs = crc16(0, (u8 *)lh, count - L2CAP_FCS_SIZE);
875 put_unaligned_le16(fcs, skb_put(skb, L2CAP_FCS_SIZE));
876 }
877
878 skb->priority = HCI_PRIO_MAX;
879 l2cap_do_send(chan, skb);
880}
881
882static inline void l2cap_send_rr_or_rnr(struct l2cap_chan *chan, u32 control)
883{
884 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
885 control |= __set_ctrl_super(chan, L2CAP_SUPER_RNR);
886 set_bit(CONN_RNR_SENT, &chan->conn_state);
887 } else
888 control |= __set_ctrl_super(chan, L2CAP_SUPER_RR);
889
890 control |= __set_reqseq(chan, chan->buffer_seq);
891
892 l2cap_send_sframe(chan, control);
893}
894
895static inline int __l2cap_no_conn_pending(struct l2cap_chan *chan)
896{
897 return !test_bit(CONF_CONNECT_PEND, &chan->conf_state);
898}
899
900static void l2cap_send_conn_req(struct l2cap_chan *chan)
901{
902 struct l2cap_conn *conn = chan->conn;
903 struct l2cap_conn_req req;
904
905 req.scid = cpu_to_le16(chan->scid);
906 req.psm = chan->psm;
907
908 chan->ident = l2cap_get_ident(conn);
909
910 set_bit(CONF_CONNECT_PEND, &chan->conf_state);
911
912 l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_REQ, sizeof(req), &req);
913}
914
915static void l2cap_chan_ready(struct l2cap_chan *chan)
916{
917 struct sock *sk = chan->sk;
918 struct sock *parent;
919
920 lock_sock(sk);
921
922 parent = bt_sk(sk)->parent;
923
924 BT_DBG("sk %p, parent %p", sk, parent);
925
926 chan->conf_state = 0;
927 __clear_chan_timer(chan);
928
929 __l2cap_state_change(chan, BT_CONNECTED);
930 sk->sk_state_change(sk);
931
932 if (parent)
933 parent->sk_data_ready(parent, 0);
934
935 release_sock(sk);
936}
937
938static void l2cap_do_start(struct l2cap_chan *chan)
939{
940 struct l2cap_conn *conn = chan->conn;
941
942 if (conn->hcon->type == LE_LINK) {
943 l2cap_chan_ready(chan);
944 return;
945 }
946
947 if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT) {
948 if (!(conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE))
949 return;
950
951 if (l2cap_chan_check_security(chan) &&
952 __l2cap_no_conn_pending(chan))
953 l2cap_send_conn_req(chan);
954 } else {
955 struct l2cap_info_req req;
956 req.type = cpu_to_le16(L2CAP_IT_FEAT_MASK);
957
958 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_SENT;
959 conn->info_ident = l2cap_get_ident(conn);
960
961 schedule_delayed_work(&conn->info_timer, L2CAP_INFO_TIMEOUT);
962
963 l2cap_send_cmd(conn, conn->info_ident,
964 L2CAP_INFO_REQ, sizeof(req), &req);
965 }
966}
967
968static inline int l2cap_mode_supported(__u8 mode, __u32 feat_mask)
969{
970 u32 local_feat_mask = l2cap_feat_mask;
971 if (!disable_ertm)
972 local_feat_mask |= L2CAP_FEAT_ERTM | L2CAP_FEAT_STREAMING;
973
974 switch (mode) {
975 case L2CAP_MODE_ERTM:
976 return L2CAP_FEAT_ERTM & feat_mask & local_feat_mask;
977 case L2CAP_MODE_STREAMING:
978 return L2CAP_FEAT_STREAMING & feat_mask & local_feat_mask;
979 default:
980 return 0x00;
981 }
982}
983
984static void l2cap_send_disconn_req(struct l2cap_conn *conn, struct l2cap_chan *chan, int err)
985{
986 struct sock *sk = chan->sk;
987 struct l2cap_disconn_req req;
988
989 if (!conn)
990 return;
991
992 if (chan->mode == L2CAP_MODE_ERTM) {
993 __clear_retrans_timer(chan);
994 __clear_monitor_timer(chan);
995 __clear_ack_timer(chan);
996 }
997
998 req.dcid = cpu_to_le16(chan->dcid);
999 req.scid = cpu_to_le16(chan->scid);
1000 l2cap_send_cmd(conn, l2cap_get_ident(conn),
1001 L2CAP_DISCONN_REQ, sizeof(req), &req);
1002
1003 lock_sock(sk);
1004 __l2cap_state_change(chan, BT_DISCONN);
1005 __l2cap_chan_set_err(chan, err);
1006 release_sock(sk);
1007}
1008
1009/* ---- L2CAP connections ---- */
1010static void l2cap_conn_start(struct l2cap_conn *conn)
1011{
1012 struct l2cap_chan *chan, *tmp;
1013
1014 BT_DBG("conn %p", conn);
1015
1016 mutex_lock(&conn->chan_lock);
1017
1018 list_for_each_entry_safe(chan, tmp, &conn->chan_l, list) {
1019 struct sock *sk = chan->sk;
1020
1021 l2cap_chan_lock(chan);
1022
1023 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) {
1024 l2cap_chan_unlock(chan);
1025 continue;
1026 }
1027
1028 if (chan->state == BT_CONNECT) {
1029 if (!l2cap_chan_check_security(chan) ||
1030 !__l2cap_no_conn_pending(chan)) {
1031 l2cap_chan_unlock(chan);
1032 continue;
1033 }
1034
1035 if (!l2cap_mode_supported(chan->mode, conn->feat_mask)
1036 && test_bit(CONF_STATE2_DEVICE,
1037 &chan->conf_state)) {
1038 l2cap_chan_close(chan, ECONNRESET);
1039 l2cap_chan_unlock(chan);
1040 continue;
1041 }
1042
1043 l2cap_send_conn_req(chan);
1044
1045 } else if (chan->state == BT_CONNECT2) {
1046 struct l2cap_conn_rsp rsp;
1047 char buf[128];
1048 rsp.scid = cpu_to_le16(chan->dcid);
1049 rsp.dcid = cpu_to_le16(chan->scid);
1050
1051 if (l2cap_chan_check_security(chan)) {
1052 lock_sock(sk);
1053 if (test_bit(BT_SK_DEFER_SETUP,
1054 &bt_sk(sk)->flags)) {
1055 struct sock *parent = bt_sk(sk)->parent;
1056 rsp.result = cpu_to_le16(L2CAP_CR_PEND);
1057 rsp.status = cpu_to_le16(L2CAP_CS_AUTHOR_PEND);
1058 if (parent)
1059 parent->sk_data_ready(parent, 0);
1060
1061 } else {
1062 __l2cap_state_change(chan, BT_CONFIG);
1063 rsp.result = cpu_to_le16(L2CAP_CR_SUCCESS);
1064 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
1065 }
1066 release_sock(sk);
1067 } else {
1068 rsp.result = cpu_to_le16(L2CAP_CR_PEND);
1069 rsp.status = cpu_to_le16(L2CAP_CS_AUTHEN_PEND);
1070 }
1071
1072 l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_RSP,
1073 sizeof(rsp), &rsp);
1074
1075 if (test_bit(CONF_REQ_SENT, &chan->conf_state) ||
1076 rsp.result != L2CAP_CR_SUCCESS) {
1077 l2cap_chan_unlock(chan);
1078 continue;
1079 }
1080
1081 set_bit(CONF_REQ_SENT, &chan->conf_state);
1082 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
1083 l2cap_build_conf_req(chan, buf), buf);
1084 chan->num_conf_req++;
1085 }
1086
1087 l2cap_chan_unlock(chan);
1088 }
1089
1090 mutex_unlock(&conn->chan_lock);
1091}
1092
1093/* Find socket with cid and source/destination bdaddr.
1094 * Returns closest match, locked.
1095 */
1096static struct l2cap_chan *l2cap_global_chan_by_scid(int state, u16 cid,
1097 bdaddr_t *src,
1098 bdaddr_t *dst)
1099{
1100 struct l2cap_chan *c, *c1 = NULL;
1101
1102 read_lock(&chan_list_lock);
1103
1104 list_for_each_entry(c, &chan_list, global_l) {
1105 struct sock *sk = c->sk;
1106
1107 if (state && c->state != state)
1108 continue;
1109
1110 if (c->scid == cid) {
1111 int src_match, dst_match;
1112 int src_any, dst_any;
1113
1114 /* Exact match. */
1115 src_match = !bacmp(&bt_sk(sk)->src, src);
1116 dst_match = !bacmp(&bt_sk(sk)->dst, dst);
1117 if (src_match && dst_match) {
1118 read_unlock(&chan_list_lock);
1119 return c;
1120 }
1121
1122 /* Closest match */
1123 src_any = !bacmp(&bt_sk(sk)->src, BDADDR_ANY);
1124 dst_any = !bacmp(&bt_sk(sk)->dst, BDADDR_ANY);
1125 if ((src_match && dst_any) || (src_any && dst_match) ||
1126 (src_any && dst_any))
1127 c1 = c;
1128 }
1129 }
1130
1131 read_unlock(&chan_list_lock);
1132
1133 return c1;
1134}
1135
1136static void l2cap_le_conn_ready(struct l2cap_conn *conn)
1137{
1138 struct sock *parent, *sk;
1139 struct l2cap_chan *chan, *pchan;
1140
1141 BT_DBG("");
1142
1143 /* Check if we have socket listening on cid */
1144 pchan = l2cap_global_chan_by_scid(BT_LISTEN, L2CAP_CID_LE_DATA,
1145 conn->src, conn->dst);
1146 if (!pchan)
1147 return;
1148
1149 parent = pchan->sk;
1150
1151 lock_sock(parent);
1152
1153 /* Check for backlog size */
1154 if (sk_acceptq_is_full(parent)) {
1155 BT_DBG("backlog full %d", parent->sk_ack_backlog);
1156 goto clean;
1157 }
1158
1159 chan = pchan->ops->new_connection(pchan->data);
1160 if (!chan)
1161 goto clean;
1162
1163 sk = chan->sk;
1164
1165 hci_conn_hold(conn->hcon);
1166 conn->hcon->disc_timeout = HCI_DISCONN_TIMEOUT;
1167
1168 bacpy(&bt_sk(sk)->src, conn->src);
1169 bacpy(&bt_sk(sk)->dst, conn->dst);
1170
1171 bt_accept_enqueue(parent, sk);
1172
1173 l2cap_chan_add(conn, chan);
1174
1175 __set_chan_timer(chan, sk->sk_sndtimeo);
1176
1177 __l2cap_state_change(chan, BT_CONNECTED);
1178 parent->sk_data_ready(parent, 0);
1179
1180clean:
1181 release_sock(parent);
1182}
1183
1184static void l2cap_conn_ready(struct l2cap_conn *conn)
1185{
1186 struct l2cap_chan *chan;
1187 struct hci_conn *hcon = conn->hcon;
1188
1189 BT_DBG("conn %p", conn);
1190
1191 if (!hcon->out && hcon->type == LE_LINK)
1192 l2cap_le_conn_ready(conn);
1193
1194 if (hcon->out && hcon->type == LE_LINK)
1195 smp_conn_security(hcon, hcon->pending_sec_level);
1196
1197 mutex_lock(&conn->chan_lock);
1198
1199 list_for_each_entry(chan, &conn->chan_l, list) {
1200
1201 l2cap_chan_lock(chan);
1202
1203 if (hcon->type == LE_LINK) {
1204 if (smp_conn_security(hcon, chan->sec_level))
1205 l2cap_chan_ready(chan);
1206
1207 } else if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) {
1208 struct sock *sk = chan->sk;
1209 __clear_chan_timer(chan);
1210 lock_sock(sk);
1211 __l2cap_state_change(chan, BT_CONNECTED);
1212 sk->sk_state_change(sk);
1213 release_sock(sk);
1214
1215 } else if (chan->state == BT_CONNECT)
1216 l2cap_do_start(chan);
1217
1218 l2cap_chan_unlock(chan);
1219 }
1220
1221 mutex_unlock(&conn->chan_lock);
1222}
1223
1224/* Notify sockets that we cannot guaranty reliability anymore */
1225static void l2cap_conn_unreliable(struct l2cap_conn *conn, int err)
1226{
1227 struct l2cap_chan *chan;
1228
1229 BT_DBG("conn %p", conn);
1230
1231 mutex_lock(&conn->chan_lock);
1232
1233 list_for_each_entry(chan, &conn->chan_l, list) {
1234 if (test_bit(FLAG_FORCE_RELIABLE, &chan->flags))
1235 __l2cap_chan_set_err(chan, err);
1236 }
1237
1238 mutex_unlock(&conn->chan_lock);
1239}
1240
1241static void l2cap_info_timeout(struct work_struct *work)
1242{
1243 struct l2cap_conn *conn = container_of(work, struct l2cap_conn,
1244 info_timer.work);
1245
1246 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
1247 conn->info_ident = 0;
1248
1249 l2cap_conn_start(conn);
1250}
1251
1252static void l2cap_conn_del(struct hci_conn *hcon, int err)
1253{
1254 struct l2cap_conn *conn = hcon->l2cap_data;
1255 struct l2cap_chan *chan, *l;
1256
1257 if (!conn)
1258 return;
1259
1260 BT_DBG("hcon %p conn %p, err %d", hcon, conn, err);
1261
1262 kfree_skb(conn->rx_skb);
1263
1264 mutex_lock(&conn->chan_lock);
1265
1266 /* Kill channels */
1267 list_for_each_entry_safe(chan, l, &conn->chan_l, list) {
1268 l2cap_chan_hold(chan);
1269 l2cap_chan_lock(chan);
1270
1271 l2cap_chan_del(chan, err);
1272
1273 l2cap_chan_unlock(chan);
1274
1275 chan->ops->close(chan->data);
1276 l2cap_chan_put(chan);
1277 }
1278
1279 mutex_unlock(&conn->chan_lock);
1280
1281 hci_chan_del(conn->hchan);
1282
1283 if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT)
1284 cancel_delayed_work_sync(&conn->info_timer);
1285
1286 if (test_and_clear_bit(HCI_CONN_LE_SMP_PEND, &hcon->flags)) {
1287 cancel_delayed_work_sync(&conn->security_timer);
1288 smp_chan_destroy(conn);
1289 }
1290
1291 hcon->l2cap_data = NULL;
1292 kfree(conn);
1293}
1294
1295static void security_timeout(struct work_struct *work)
1296{
1297 struct l2cap_conn *conn = container_of(work, struct l2cap_conn,
1298 security_timer.work);
1299
1300 BT_DBG("conn %p", conn);
1301
1302 if (test_and_clear_bit(HCI_CONN_LE_SMP_PEND, &conn->hcon->flags)) {
1303 smp_chan_destroy(conn);
1304 l2cap_conn_del(conn->hcon, ETIMEDOUT);
1305 }
1306}
1307
1308static struct l2cap_conn *l2cap_conn_add(struct hci_conn *hcon, u8 status)
1309{
1310 struct l2cap_conn *conn = hcon->l2cap_data;
1311 struct hci_chan *hchan;
1312
1313 if (conn || status)
1314 return conn;
1315
1316 hchan = hci_chan_create(hcon);
1317 if (!hchan)
1318 return NULL;
1319
1320 conn = kzalloc(sizeof(struct l2cap_conn), GFP_ATOMIC);
1321 if (!conn) {
1322 hci_chan_del(hchan);
1323 return NULL;
1324 }
1325
1326 hcon->l2cap_data = conn;
1327 conn->hcon = hcon;
1328 conn->hchan = hchan;
1329
1330 BT_DBG("hcon %p conn %p hchan %p", hcon, conn, hchan);
1331
1332 if (hcon->hdev->le_mtu && hcon->type == LE_LINK)
1333 conn->mtu = hcon->hdev->le_mtu;
1334 else
1335 conn->mtu = hcon->hdev->acl_mtu;
1336
1337 conn->src = &hcon->hdev->bdaddr;
1338 conn->dst = &hcon->dst;
1339
1340 conn->feat_mask = 0;
1341
1342 spin_lock_init(&conn->lock);
1343 mutex_init(&conn->chan_lock);
1344
1345 INIT_LIST_HEAD(&conn->chan_l);
1346
1347 if (hcon->type == LE_LINK)
1348 INIT_DELAYED_WORK(&conn->security_timer, security_timeout);
1349 else
1350 INIT_DELAYED_WORK(&conn->info_timer, l2cap_info_timeout);
1351
1352 conn->disc_reason = HCI_ERROR_REMOTE_USER_TERM;
1353
1354 return conn;
1355}
1356
1357/* ---- Socket interface ---- */
1358
1359/* Find socket with psm and source / destination bdaddr.
1360 * Returns closest match.
1361 */
1362static struct l2cap_chan *l2cap_global_chan_by_psm(int state, __le16 psm,
1363 bdaddr_t *src,
1364 bdaddr_t *dst)
1365{
1366 struct l2cap_chan *c, *c1 = NULL;
1367
1368 read_lock(&chan_list_lock);
1369
1370 list_for_each_entry(c, &chan_list, global_l) {
1371 struct sock *sk = c->sk;
1372
1373 if (state && c->state != state)
1374 continue;
1375
1376 if (c->psm == psm) {
1377 int src_match, dst_match;
1378 int src_any, dst_any;
1379
1380 /* Exact match. */
1381 src_match = !bacmp(&bt_sk(sk)->src, src);
1382 dst_match = !bacmp(&bt_sk(sk)->dst, dst);
1383 if (src_match && dst_match) {
1384 read_unlock(&chan_list_lock);
1385 return c;
1386 }
1387
1388 /* Closest match */
1389 src_any = !bacmp(&bt_sk(sk)->src, BDADDR_ANY);
1390 dst_any = !bacmp(&bt_sk(sk)->dst, BDADDR_ANY);
1391 if ((src_match && dst_any) || (src_any && dst_match) ||
1392 (src_any && dst_any))
1393 c1 = c;
1394 }
1395 }
1396
1397 read_unlock(&chan_list_lock);
1398
1399 return c1;
1400}
1401
1402int l2cap_chan_connect(struct l2cap_chan *chan, __le16 psm, u16 cid,
1403 bdaddr_t *dst, u8 dst_type)
1404{
1405 struct sock *sk = chan->sk;
1406 bdaddr_t *src = &bt_sk(sk)->src;
1407 struct l2cap_conn *conn;
1408 struct hci_conn *hcon;
1409 struct hci_dev *hdev;
1410 __u8 auth_type;
1411 int err;
1412
1413 BT_DBG("%s -> %s (type %u) psm 0x%2.2x", batostr(src), batostr(dst),
1414 dst_type, __le16_to_cpu(chan->psm));
1415
1416 hdev = hci_get_route(dst, src);
1417 if (!hdev)
1418 return -EHOSTUNREACH;
1419
1420 hci_dev_lock(hdev);
1421
1422 l2cap_chan_lock(chan);
1423
1424 /* PSM must be odd and lsb of upper byte must be 0 */
1425 if ((__le16_to_cpu(psm) & 0x0101) != 0x0001 && !cid &&
1426 chan->chan_type != L2CAP_CHAN_RAW) {
1427 err = -EINVAL;
1428 goto done;
1429 }
1430
1431 if (chan->chan_type == L2CAP_CHAN_CONN_ORIENTED && !(psm || cid)) {
1432 err = -EINVAL;
1433 goto done;
1434 }
1435
1436 switch (chan->mode) {
1437 case L2CAP_MODE_BASIC:
1438 break;
1439 case L2CAP_MODE_ERTM:
1440 case L2CAP_MODE_STREAMING:
1441 if (!disable_ertm)
1442 break;
1443 /* fall through */
1444 default:
1445 err = -ENOTSUPP;
1446 goto done;
1447 }
1448
1449 lock_sock(sk);
1450
1451 switch (sk->sk_state) {
1452 case BT_CONNECT:
1453 case BT_CONNECT2:
1454 case BT_CONFIG:
1455 /* Already connecting */
1456 err = 0;
1457 release_sock(sk);
1458 goto done;
1459
1460 case BT_CONNECTED:
1461 /* Already connected */
1462 err = -EISCONN;
1463 release_sock(sk);
1464 goto done;
1465
1466 case BT_OPEN:
1467 case BT_BOUND:
1468 /* Can connect */
1469 break;
1470
1471 default:
1472 err = -EBADFD;
1473 release_sock(sk);
1474 goto done;
1475 }
1476
1477 /* Set destination address and psm */
1478 bacpy(&bt_sk(sk)->dst, dst);
1479
1480 release_sock(sk);
1481
1482 chan->psm = psm;
1483 chan->dcid = cid;
1484
1485 auth_type = l2cap_get_auth_type(chan);
1486
1487 if (chan->dcid == L2CAP_CID_LE_DATA)
1488 hcon = hci_connect(hdev, LE_LINK, dst, dst_type,
1489 chan->sec_level, auth_type);
1490 else
1491 hcon = hci_connect(hdev, ACL_LINK, dst, dst_type,
1492 chan->sec_level, auth_type);
1493
1494 if (IS_ERR(hcon)) {
1495 err = PTR_ERR(hcon);
1496 goto done;
1497 }
1498
1499 conn = l2cap_conn_add(hcon, 0);
1500 if (!conn) {
1501 hci_conn_put(hcon);
1502 err = -ENOMEM;
1503 goto done;
1504 }
1505
1506 if (hcon->type == LE_LINK) {
1507 err = 0;
1508
1509 if (!list_empty(&conn->chan_l)) {
1510 err = -EBUSY;
1511 hci_conn_put(hcon);
1512 }
1513
1514 if (err)
1515 goto done;
1516 }
1517
1518 /* Update source addr of the socket */
1519 bacpy(src, conn->src);
1520
1521 l2cap_chan_unlock(chan);
1522 l2cap_chan_add(conn, chan);
1523 l2cap_chan_lock(chan);
1524
1525 l2cap_state_change(chan, BT_CONNECT);
1526 __set_chan_timer(chan, sk->sk_sndtimeo);
1527
1528 if (hcon->state == BT_CONNECTED) {
1529 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) {
1530 __clear_chan_timer(chan);
1531 if (l2cap_chan_check_security(chan))
1532 l2cap_state_change(chan, BT_CONNECTED);
1533 } else
1534 l2cap_do_start(chan);
1535 }
1536
1537 err = 0;
1538
1539done:
1540 l2cap_chan_unlock(chan);
1541 hci_dev_unlock(hdev);
1542 hci_dev_put(hdev);
1543 return err;
1544}
1545
1546int __l2cap_wait_ack(struct sock *sk)
1547{
1548 struct l2cap_chan *chan = l2cap_pi(sk)->chan;
1549 DECLARE_WAITQUEUE(wait, current);
1550 int err = 0;
1551 int timeo = HZ/5;
1552
1553 add_wait_queue(sk_sleep(sk), &wait);
1554 set_current_state(TASK_INTERRUPTIBLE);
1555 while (chan->unacked_frames > 0 && chan->conn) {
1556 if (!timeo)
1557 timeo = HZ/5;
1558
1559 if (signal_pending(current)) {
1560 err = sock_intr_errno(timeo);
1561 break;
1562 }
1563
1564 release_sock(sk);
1565 timeo = schedule_timeout(timeo);
1566 lock_sock(sk);
1567 set_current_state(TASK_INTERRUPTIBLE);
1568
1569 err = sock_error(sk);
1570 if (err)
1571 break;
1572 }
1573 set_current_state(TASK_RUNNING);
1574 remove_wait_queue(sk_sleep(sk), &wait);
1575 return err;
1576}
1577
1578static void l2cap_monitor_timeout(struct work_struct *work)
1579{
1580 struct l2cap_chan *chan = container_of(work, struct l2cap_chan,
1581 monitor_timer.work);
1582
1583 BT_DBG("chan %p", chan);
1584
1585 l2cap_chan_lock(chan);
1586
1587 if (chan->retry_count >= chan->remote_max_tx) {
1588 l2cap_send_disconn_req(chan->conn, chan, ECONNABORTED);
1589 l2cap_chan_unlock(chan);
1590 l2cap_chan_put(chan);
1591 return;
1592 }
1593
1594 chan->retry_count++;
1595 __set_monitor_timer(chan);
1596
1597 l2cap_send_rr_or_rnr(chan, L2CAP_CTRL_POLL);
1598 l2cap_chan_unlock(chan);
1599 l2cap_chan_put(chan);
1600}
1601
1602static void l2cap_retrans_timeout(struct work_struct *work)
1603{
1604 struct l2cap_chan *chan = container_of(work, struct l2cap_chan,
1605 retrans_timer.work);
1606
1607 BT_DBG("chan %p", chan);
1608
1609 l2cap_chan_lock(chan);
1610
1611 chan->retry_count = 1;
1612 __set_monitor_timer(chan);
1613
1614 set_bit(CONN_WAIT_F, &chan->conn_state);
1615
1616 l2cap_send_rr_or_rnr(chan, L2CAP_CTRL_POLL);
1617
1618 l2cap_chan_unlock(chan);
1619 l2cap_chan_put(chan);
1620}
1621
1622static void l2cap_drop_acked_frames(struct l2cap_chan *chan)
1623{
1624 struct sk_buff *skb;
1625
1626 while ((skb = skb_peek(&chan->tx_q)) &&
1627 chan->unacked_frames) {
1628 if (bt_cb(skb)->control.txseq == chan->expected_ack_seq)
1629 break;
1630
1631 skb = skb_dequeue(&chan->tx_q);
1632 kfree_skb(skb);
1633
1634 chan->unacked_frames--;
1635 }
1636
1637 if (!chan->unacked_frames)
1638 __clear_retrans_timer(chan);
1639}
1640
1641static void l2cap_streaming_send(struct l2cap_chan *chan)
1642{
1643 struct sk_buff *skb;
1644 u32 control;
1645 u16 fcs;
1646
1647 while ((skb = skb_dequeue(&chan->tx_q))) {
1648 control = __get_control(chan, skb->data + L2CAP_HDR_SIZE);
1649 control |= __set_txseq(chan, chan->next_tx_seq);
1650 control |= __set_ctrl_sar(chan, bt_cb(skb)->control.sar);
1651 __put_control(chan, control, skb->data + L2CAP_HDR_SIZE);
1652
1653 if (chan->fcs == L2CAP_FCS_CRC16) {
1654 fcs = crc16(0, (u8 *)skb->data,
1655 skb->len - L2CAP_FCS_SIZE);
1656 put_unaligned_le16(fcs,
1657 skb->data + skb->len - L2CAP_FCS_SIZE);
1658 }
1659
1660 l2cap_do_send(chan, skb);
1661
1662 chan->next_tx_seq = __next_seq(chan, chan->next_tx_seq);
1663 }
1664}
1665
1666static void l2cap_retransmit_one_frame(struct l2cap_chan *chan, u16 tx_seq)
1667{
1668 struct sk_buff *skb, *tx_skb;
1669 u16 fcs;
1670 u32 control;
1671
1672 skb = skb_peek(&chan->tx_q);
1673 if (!skb)
1674 return;
1675
1676 while (bt_cb(skb)->control.txseq != tx_seq) {
1677 if (skb_queue_is_last(&chan->tx_q, skb))
1678 return;
1679
1680 skb = skb_queue_next(&chan->tx_q, skb);
1681 }
1682
1683 if (bt_cb(skb)->control.retries == chan->remote_max_tx &&
1684 chan->remote_max_tx) {
1685 l2cap_send_disconn_req(chan->conn, chan, ECONNABORTED);
1686 return;
1687 }
1688
1689 tx_skb = skb_clone(skb, GFP_ATOMIC);
1690 bt_cb(skb)->control.retries++;
1691
1692 control = __get_control(chan, tx_skb->data + L2CAP_HDR_SIZE);
1693 control &= __get_sar_mask(chan);
1694
1695 if (test_and_clear_bit(CONN_SEND_FBIT, &chan->conn_state))
1696 control |= __set_ctrl_final(chan);
1697
1698 control |= __set_reqseq(chan, chan->buffer_seq);
1699 control |= __set_txseq(chan, tx_seq);
1700
1701 __put_control(chan, control, tx_skb->data + L2CAP_HDR_SIZE);
1702
1703 if (chan->fcs == L2CAP_FCS_CRC16) {
1704 fcs = crc16(0, (u8 *)tx_skb->data,
1705 tx_skb->len - L2CAP_FCS_SIZE);
1706 put_unaligned_le16(fcs,
1707 tx_skb->data + tx_skb->len - L2CAP_FCS_SIZE);
1708 }
1709
1710 l2cap_do_send(chan, tx_skb);
1711}
1712
1713static int l2cap_ertm_send(struct l2cap_chan *chan)
1714{
1715 struct sk_buff *skb, *tx_skb;
1716 u16 fcs;
1717 u32 control;
1718 int nsent = 0;
1719
1720 if (chan->state != BT_CONNECTED)
1721 return -ENOTCONN;
1722
1723 if (test_bit(CONN_REMOTE_BUSY, &chan->conn_state))
1724 return 0;
1725
1726 while ((skb = chan->tx_send_head) && (!l2cap_tx_window_full(chan))) {
1727
1728 if (bt_cb(skb)->control.retries == chan->remote_max_tx &&
1729 chan->remote_max_tx) {
1730 l2cap_send_disconn_req(chan->conn, chan, ECONNABORTED);
1731 break;
1732 }
1733
1734 tx_skb = skb_clone(skb, GFP_ATOMIC);
1735
1736 bt_cb(skb)->control.retries++;
1737
1738 control = __get_control(chan, tx_skb->data + L2CAP_HDR_SIZE);
1739 control &= __get_sar_mask(chan);
1740
1741 if (test_and_clear_bit(CONN_SEND_FBIT, &chan->conn_state))
1742 control |= __set_ctrl_final(chan);
1743
1744 control |= __set_reqseq(chan, chan->buffer_seq);
1745 control |= __set_txseq(chan, chan->next_tx_seq);
1746 control |= __set_ctrl_sar(chan, bt_cb(skb)->control.sar);
1747
1748 __put_control(chan, control, tx_skb->data + L2CAP_HDR_SIZE);
1749
1750 if (chan->fcs == L2CAP_FCS_CRC16) {
1751 fcs = crc16(0, (u8 *)skb->data,
1752 tx_skb->len - L2CAP_FCS_SIZE);
1753 put_unaligned_le16(fcs, skb->data +
1754 tx_skb->len - L2CAP_FCS_SIZE);
1755 }
1756
1757 l2cap_do_send(chan, tx_skb);
1758
1759 __set_retrans_timer(chan);
1760
1761 bt_cb(skb)->control.txseq = chan->next_tx_seq;
1762
1763 chan->next_tx_seq = __next_seq(chan, chan->next_tx_seq);
1764
1765 if (bt_cb(skb)->control.retries == 1) {
1766 chan->unacked_frames++;
1767
1768 if (!nsent++)
1769 __clear_ack_timer(chan);
1770 }
1771
1772 chan->frames_sent++;
1773
1774 if (skb_queue_is_last(&chan->tx_q, skb))
1775 chan->tx_send_head = NULL;
1776 else
1777 chan->tx_send_head = skb_queue_next(&chan->tx_q, skb);
1778 }
1779
1780 return nsent;
1781}
1782
1783static int l2cap_retransmit_frames(struct l2cap_chan *chan)
1784{
1785 int ret;
1786
1787 if (!skb_queue_empty(&chan->tx_q))
1788 chan->tx_send_head = chan->tx_q.next;
1789
1790 chan->next_tx_seq = chan->expected_ack_seq;
1791 ret = l2cap_ertm_send(chan);
1792 return ret;
1793}
1794
1795static void __l2cap_send_ack(struct l2cap_chan *chan)
1796{
1797 u32 control = 0;
1798
1799 control |= __set_reqseq(chan, chan->buffer_seq);
1800
1801 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
1802 control |= __set_ctrl_super(chan, L2CAP_SUPER_RNR);
1803 set_bit(CONN_RNR_SENT, &chan->conn_state);
1804 l2cap_send_sframe(chan, control);
1805 return;
1806 }
1807
1808 if (l2cap_ertm_send(chan) > 0)
1809 return;
1810
1811 control |= __set_ctrl_super(chan, L2CAP_SUPER_RR);
1812 l2cap_send_sframe(chan, control);
1813}
1814
1815static void l2cap_send_ack(struct l2cap_chan *chan)
1816{
1817 __clear_ack_timer(chan);
1818 __l2cap_send_ack(chan);
1819}
1820
1821static void l2cap_send_srejtail(struct l2cap_chan *chan)
1822{
1823 struct srej_list *tail;
1824 u32 control;
1825
1826 control = __set_ctrl_super(chan, L2CAP_SUPER_SREJ);
1827 control |= __set_ctrl_final(chan);
1828
1829 tail = list_entry((&chan->srej_l)->prev, struct srej_list, list);
1830 control |= __set_reqseq(chan, tail->tx_seq);
1831
1832 l2cap_send_sframe(chan, control);
1833}
1834
1835static inline int l2cap_skbuff_fromiovec(struct l2cap_chan *chan,
1836 struct msghdr *msg, int len,
1837 int count, struct sk_buff *skb)
1838{
1839 struct l2cap_conn *conn = chan->conn;
1840 struct sk_buff **frag;
1841 int sent = 0;
1842
1843 if (memcpy_fromiovec(skb_put(skb, count), msg->msg_iov, count))
1844 return -EFAULT;
1845
1846 sent += count;
1847 len -= count;
1848
1849 /* Continuation fragments (no L2CAP header) */
1850 frag = &skb_shinfo(skb)->frag_list;
1851 while (len) {
1852 struct sk_buff *tmp;
1853
1854 count = min_t(unsigned int, conn->mtu, len);
1855
1856 tmp = chan->ops->alloc_skb(chan, count,
1857 msg->msg_flags & MSG_DONTWAIT);
1858 if (IS_ERR(tmp))
1859 return PTR_ERR(tmp);
1860
1861 *frag = tmp;
1862
1863 if (memcpy_fromiovec(skb_put(*frag, count), msg->msg_iov, count))
1864 return -EFAULT;
1865
1866 (*frag)->priority = skb->priority;
1867
1868 sent += count;
1869 len -= count;
1870
1871 skb->len += (*frag)->len;
1872 skb->data_len += (*frag)->len;
1873
1874 frag = &(*frag)->next;
1875 }
1876
1877 return sent;
1878}
1879
1880static struct sk_buff *l2cap_create_connless_pdu(struct l2cap_chan *chan,
1881 struct msghdr *msg, size_t len,
1882 u32 priority)
1883{
1884 struct l2cap_conn *conn = chan->conn;
1885 struct sk_buff *skb;
1886 int err, count, hlen = L2CAP_HDR_SIZE + L2CAP_PSMLEN_SIZE;
1887 struct l2cap_hdr *lh;
1888
1889 BT_DBG("chan %p len %d priority %u", chan, (int)len, priority);
1890
1891 count = min_t(unsigned int, (conn->mtu - hlen), len);
1892
1893 skb = chan->ops->alloc_skb(chan, count + hlen,
1894 msg->msg_flags & MSG_DONTWAIT);
1895 if (IS_ERR(skb))
1896 return skb;
1897
1898 skb->priority = priority;
1899
1900 /* Create L2CAP header */
1901 lh = (struct l2cap_hdr *) skb_put(skb, L2CAP_HDR_SIZE);
1902 lh->cid = cpu_to_le16(chan->dcid);
1903 lh->len = cpu_to_le16(len + L2CAP_PSMLEN_SIZE);
1904 put_unaligned(chan->psm, skb_put(skb, L2CAP_PSMLEN_SIZE));
1905
1906 err = l2cap_skbuff_fromiovec(chan, msg, len, count, skb);
1907 if (unlikely(err < 0)) {
1908 kfree_skb(skb);
1909 return ERR_PTR(err);
1910 }
1911 return skb;
1912}
1913
1914static struct sk_buff *l2cap_create_basic_pdu(struct l2cap_chan *chan,
1915 struct msghdr *msg, size_t len,
1916 u32 priority)
1917{
1918 struct l2cap_conn *conn = chan->conn;
1919 struct sk_buff *skb;
1920 int err, count;
1921 struct l2cap_hdr *lh;
1922
1923 BT_DBG("chan %p len %d", chan, (int)len);
1924
1925 count = min_t(unsigned int, (conn->mtu - L2CAP_HDR_SIZE), len);
1926
1927 skb = chan->ops->alloc_skb(chan, count + L2CAP_HDR_SIZE,
1928 msg->msg_flags & MSG_DONTWAIT);
1929 if (IS_ERR(skb))
1930 return skb;
1931
1932 skb->priority = priority;
1933
1934 /* Create L2CAP header */
1935 lh = (struct l2cap_hdr *) skb_put(skb, L2CAP_HDR_SIZE);
1936 lh->cid = cpu_to_le16(chan->dcid);
1937 lh->len = cpu_to_le16(len);
1938
1939 err = l2cap_skbuff_fromiovec(chan, msg, len, count, skb);
1940 if (unlikely(err < 0)) {
1941 kfree_skb(skb);
1942 return ERR_PTR(err);
1943 }
1944 return skb;
1945}
1946
1947static struct sk_buff *l2cap_create_iframe_pdu(struct l2cap_chan *chan,
1948 struct msghdr *msg, size_t len,
1949 u16 sdulen)
1950{
1951 struct l2cap_conn *conn = chan->conn;
1952 struct sk_buff *skb;
1953 int err, count, hlen;
1954 struct l2cap_hdr *lh;
1955
1956 BT_DBG("chan %p len %d", chan, (int)len);
1957
1958 if (!conn)
1959 return ERR_PTR(-ENOTCONN);
1960
1961 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
1962 hlen = L2CAP_EXT_HDR_SIZE;
1963 else
1964 hlen = L2CAP_ENH_HDR_SIZE;
1965
1966 if (sdulen)
1967 hlen += L2CAP_SDULEN_SIZE;
1968
1969 if (chan->fcs == L2CAP_FCS_CRC16)
1970 hlen += L2CAP_FCS_SIZE;
1971
1972 count = min_t(unsigned int, (conn->mtu - hlen), len);
1973
1974 skb = chan->ops->alloc_skb(chan, count + hlen,
1975 msg->msg_flags & MSG_DONTWAIT);
1976 if (IS_ERR(skb))
1977 return skb;
1978
1979 /* Create L2CAP header */
1980 lh = (struct l2cap_hdr *) skb_put(skb, L2CAP_HDR_SIZE);
1981 lh->cid = cpu_to_le16(chan->dcid);
1982 lh->len = cpu_to_le16(len + (hlen - L2CAP_HDR_SIZE));
1983
1984 __put_control(chan, 0, skb_put(skb, __ctrl_size(chan)));
1985
1986 if (sdulen)
1987 put_unaligned_le16(sdulen, skb_put(skb, L2CAP_SDULEN_SIZE));
1988
1989 err = l2cap_skbuff_fromiovec(chan, msg, len, count, skb);
1990 if (unlikely(err < 0)) {
1991 kfree_skb(skb);
1992 return ERR_PTR(err);
1993 }
1994
1995 if (chan->fcs == L2CAP_FCS_CRC16)
1996 put_unaligned_le16(0, skb_put(skb, L2CAP_FCS_SIZE));
1997
1998 bt_cb(skb)->control.retries = 0;
1999 return skb;
2000}
2001
2002static int l2cap_segment_sdu(struct l2cap_chan *chan,
2003 struct sk_buff_head *seg_queue,
2004 struct msghdr *msg, size_t len)
2005{
2006 struct sk_buff *skb;
2007 u16 sdu_len;
2008 size_t pdu_len;
2009 int err = 0;
2010 u8 sar;
2011
2012 BT_DBG("chan %p, msg %p, len %d", chan, msg, (int)len);
2013
2014 /* It is critical that ERTM PDUs fit in a single HCI fragment,
2015 * so fragmented skbs are not used. The HCI layer's handling
2016 * of fragmented skbs is not compatible with ERTM's queueing.
2017 */
2018
2019 /* PDU size is derived from the HCI MTU */
2020 pdu_len = chan->conn->mtu;
2021
2022 pdu_len = min_t(size_t, pdu_len, L2CAP_BREDR_MAX_PAYLOAD);
2023
2024 /* Adjust for largest possible L2CAP overhead. */
2025 pdu_len -= L2CAP_EXT_HDR_SIZE + L2CAP_FCS_SIZE;
2026
2027 /* Remote device may have requested smaller PDUs */
2028 pdu_len = min_t(size_t, pdu_len, chan->remote_mps);
2029
2030 if (len <= pdu_len) {
2031 sar = L2CAP_SAR_UNSEGMENTED;
2032 sdu_len = 0;
2033 pdu_len = len;
2034 } else {
2035 sar = L2CAP_SAR_START;
2036 sdu_len = len;
2037 pdu_len -= L2CAP_SDULEN_SIZE;
2038 }
2039
2040 while (len > 0) {
2041 skb = l2cap_create_iframe_pdu(chan, msg, pdu_len, sdu_len);
2042
2043 if (IS_ERR(skb)) {
2044 __skb_queue_purge(seg_queue);
2045 return PTR_ERR(skb);
2046 }
2047
2048 bt_cb(skb)->control.sar = sar;
2049 __skb_queue_tail(seg_queue, skb);
2050
2051 len -= pdu_len;
2052 if (sdu_len) {
2053 sdu_len = 0;
2054 pdu_len += L2CAP_SDULEN_SIZE;
2055 }
2056
2057 if (len <= pdu_len) {
2058 sar = L2CAP_SAR_END;
2059 pdu_len = len;
2060 } else {
2061 sar = L2CAP_SAR_CONTINUE;
2062 }
2063 }
2064
2065 return err;
2066}
2067
2068int l2cap_chan_send(struct l2cap_chan *chan, struct msghdr *msg, size_t len,
2069 u32 priority)
2070{
2071 struct sk_buff *skb;
2072 int err;
2073 struct sk_buff_head seg_queue;
2074
2075 /* Connectionless channel */
2076 if (chan->chan_type == L2CAP_CHAN_CONN_LESS) {
2077 skb = l2cap_create_connless_pdu(chan, msg, len, priority);
2078 if (IS_ERR(skb))
2079 return PTR_ERR(skb);
2080
2081 l2cap_do_send(chan, skb);
2082 return len;
2083 }
2084
2085 switch (chan->mode) {
2086 case L2CAP_MODE_BASIC:
2087 /* Check outgoing MTU */
2088 if (len > chan->omtu)
2089 return -EMSGSIZE;
2090
2091 /* Create a basic PDU */
2092 skb = l2cap_create_basic_pdu(chan, msg, len, priority);
2093 if (IS_ERR(skb))
2094 return PTR_ERR(skb);
2095
2096 l2cap_do_send(chan, skb);
2097 err = len;
2098 break;
2099
2100 case L2CAP_MODE_ERTM:
2101 case L2CAP_MODE_STREAMING:
2102 /* Check outgoing MTU */
2103 if (len > chan->omtu) {
2104 err = -EMSGSIZE;
2105 break;
2106 }
2107
2108 __skb_queue_head_init(&seg_queue);
2109
2110 /* Do segmentation before calling in to the state machine,
2111 * since it's possible to block while waiting for memory
2112 * allocation.
2113 */
2114 err = l2cap_segment_sdu(chan, &seg_queue, msg, len);
2115
2116 /* The channel could have been closed while segmenting,
2117 * check that it is still connected.
2118 */
2119 if (chan->state != BT_CONNECTED) {
2120 __skb_queue_purge(&seg_queue);
2121 err = -ENOTCONN;
2122 }
2123
2124 if (err)
2125 break;
2126
2127 if (chan->mode == L2CAP_MODE_ERTM && chan->tx_send_head == NULL)
2128 chan->tx_send_head = seg_queue.next;
2129 skb_queue_splice_tail_init(&seg_queue, &chan->tx_q);
2130
2131 if (chan->mode == L2CAP_MODE_ERTM)
2132 err = l2cap_ertm_send(chan);
2133 else
2134 l2cap_streaming_send(chan);
2135
2136 if (err >= 0)
2137 err = len;
2138
2139 /* If the skbs were not queued for sending, they'll still be in
2140 * seg_queue and need to be purged.
2141 */
2142 __skb_queue_purge(&seg_queue);
2143 break;
2144
2145 default:
2146 BT_DBG("bad state %1.1x", chan->mode);
2147 err = -EBADFD;
2148 }
2149
2150 return err;
2151}
2152
2153/* Copy frame to all raw sockets on that connection */
2154static void l2cap_raw_recv(struct l2cap_conn *conn, struct sk_buff *skb)
2155{
2156 struct sk_buff *nskb;
2157 struct l2cap_chan *chan;
2158
2159 BT_DBG("conn %p", conn);
2160
2161 mutex_lock(&conn->chan_lock);
2162
2163 list_for_each_entry(chan, &conn->chan_l, list) {
2164 struct sock *sk = chan->sk;
2165 if (chan->chan_type != L2CAP_CHAN_RAW)
2166 continue;
2167
2168 /* Don't send frame to the socket it came from */
2169 if (skb->sk == sk)
2170 continue;
2171 nskb = skb_clone(skb, GFP_ATOMIC);
2172 if (!nskb)
2173 continue;
2174
2175 if (chan->ops->recv(chan->data, nskb))
2176 kfree_skb(nskb);
2177 }
2178
2179 mutex_unlock(&conn->chan_lock);
2180}
2181
2182/* ---- L2CAP signalling commands ---- */
2183static struct sk_buff *l2cap_build_cmd(struct l2cap_conn *conn,
2184 u8 code, u8 ident, u16 dlen, void *data)
2185{
2186 struct sk_buff *skb, **frag;
2187 struct l2cap_cmd_hdr *cmd;
2188 struct l2cap_hdr *lh;
2189 int len, count;
2190
2191 BT_DBG("conn %p, code 0x%2.2x, ident 0x%2.2x, len %d",
2192 conn, code, ident, dlen);
2193
2194 len = L2CAP_HDR_SIZE + L2CAP_CMD_HDR_SIZE + dlen;
2195 count = min_t(unsigned int, conn->mtu, len);
2196
2197 skb = bt_skb_alloc(count, GFP_ATOMIC);
2198 if (!skb)
2199 return NULL;
2200
2201 lh = (struct l2cap_hdr *) skb_put(skb, L2CAP_HDR_SIZE);
2202 lh->len = cpu_to_le16(L2CAP_CMD_HDR_SIZE + dlen);
2203
2204 if (conn->hcon->type == LE_LINK)
2205 lh->cid = cpu_to_le16(L2CAP_CID_LE_SIGNALING);
2206 else
2207 lh->cid = cpu_to_le16(L2CAP_CID_SIGNALING);
2208
2209 cmd = (struct l2cap_cmd_hdr *) skb_put(skb, L2CAP_CMD_HDR_SIZE);
2210 cmd->code = code;
2211 cmd->ident = ident;
2212 cmd->len = cpu_to_le16(dlen);
2213
2214 if (dlen) {
2215 count -= L2CAP_HDR_SIZE + L2CAP_CMD_HDR_SIZE;
2216 memcpy(skb_put(skb, count), data, count);
2217 data += count;
2218 }
2219
2220 len -= skb->len;
2221
2222 /* Continuation fragments (no L2CAP header) */
2223 frag = &skb_shinfo(skb)->frag_list;
2224 while (len) {
2225 count = min_t(unsigned int, conn->mtu, len);
2226
2227 *frag = bt_skb_alloc(count, GFP_ATOMIC);
2228 if (!*frag)
2229 goto fail;
2230
2231 memcpy(skb_put(*frag, count), data, count);
2232
2233 len -= count;
2234 data += count;
2235
2236 frag = &(*frag)->next;
2237 }
2238
2239 return skb;
2240
2241fail:
2242 kfree_skb(skb);
2243 return NULL;
2244}
2245
2246static inline int l2cap_get_conf_opt(void **ptr, int *type, int *olen, unsigned long *val)
2247{
2248 struct l2cap_conf_opt *opt = *ptr;
2249 int len;
2250
2251 len = L2CAP_CONF_OPT_SIZE + opt->len;
2252 *ptr += len;
2253
2254 *type = opt->type;
2255 *olen = opt->len;
2256
2257 switch (opt->len) {
2258 case 1:
2259 *val = *((u8 *) opt->val);
2260 break;
2261
2262 case 2:
2263 *val = get_unaligned_le16(opt->val);
2264 break;
2265
2266 case 4:
2267 *val = get_unaligned_le32(opt->val);
2268 break;
2269
2270 default:
2271 *val = (unsigned long) opt->val;
2272 break;
2273 }
2274
2275 BT_DBG("type 0x%2.2x len %d val 0x%lx", *type, opt->len, *val);
2276 return len;
2277}
2278
2279static void l2cap_add_conf_opt(void **ptr, u8 type, u8 len, unsigned long val)
2280{
2281 struct l2cap_conf_opt *opt = *ptr;
2282
2283 BT_DBG("type 0x%2.2x len %d val 0x%lx", type, len, val);
2284
2285 opt->type = type;
2286 opt->len = len;
2287
2288 switch (len) {
2289 case 1:
2290 *((u8 *) opt->val) = val;
2291 break;
2292
2293 case 2:
2294 put_unaligned_le16(val, opt->val);
2295 break;
2296
2297 case 4:
2298 put_unaligned_le32(val, opt->val);
2299 break;
2300
2301 default:
2302 memcpy(opt->val, (void *) val, len);
2303 break;
2304 }
2305
2306 *ptr += L2CAP_CONF_OPT_SIZE + len;
2307}
2308
2309static void l2cap_add_opt_efs(void **ptr, struct l2cap_chan *chan)
2310{
2311 struct l2cap_conf_efs efs;
2312
2313 switch (chan->mode) {
2314 case L2CAP_MODE_ERTM:
2315 efs.id = chan->local_id;
2316 efs.stype = chan->local_stype;
2317 efs.msdu = cpu_to_le16(chan->local_msdu);
2318 efs.sdu_itime = cpu_to_le32(chan->local_sdu_itime);
2319 efs.acc_lat = cpu_to_le32(L2CAP_DEFAULT_ACC_LAT);
2320 efs.flush_to = cpu_to_le32(L2CAP_DEFAULT_FLUSH_TO);
2321 break;
2322
2323 case L2CAP_MODE_STREAMING:
2324 efs.id = 1;
2325 efs.stype = L2CAP_SERV_BESTEFFORT;
2326 efs.msdu = cpu_to_le16(chan->local_msdu);
2327 efs.sdu_itime = cpu_to_le32(chan->local_sdu_itime);
2328 efs.acc_lat = 0;
2329 efs.flush_to = 0;
2330 break;
2331
2332 default:
2333 return;
2334 }
2335
2336 l2cap_add_conf_opt(ptr, L2CAP_CONF_EFS, sizeof(efs),
2337 (unsigned long) &efs);
2338}
2339
2340static void l2cap_ack_timeout(struct work_struct *work)
2341{
2342 struct l2cap_chan *chan = container_of(work, struct l2cap_chan,
2343 ack_timer.work);
2344
2345 BT_DBG("chan %p", chan);
2346
2347 l2cap_chan_lock(chan);
2348
2349 __l2cap_send_ack(chan);
2350
2351 l2cap_chan_unlock(chan);
2352
2353 l2cap_chan_put(chan);
2354}
2355
2356static inline int l2cap_ertm_init(struct l2cap_chan *chan)
2357{
2358 int err;
2359
2360 chan->next_tx_seq = 0;
2361 chan->expected_tx_seq = 0;
2362 chan->expected_ack_seq = 0;
2363 chan->unacked_frames = 0;
2364 chan->buffer_seq = 0;
2365 chan->num_acked = 0;
2366 chan->frames_sent = 0;
2367 chan->last_acked_seq = 0;
2368 chan->sdu = NULL;
2369 chan->sdu_last_frag = NULL;
2370 chan->sdu_len = 0;
2371
2372 skb_queue_head_init(&chan->tx_q);
2373
2374 if (chan->mode != L2CAP_MODE_ERTM)
2375 return 0;
2376
2377 chan->rx_state = L2CAP_RX_STATE_RECV;
2378 chan->tx_state = L2CAP_TX_STATE_XMIT;
2379
2380 INIT_DELAYED_WORK(&chan->retrans_timer, l2cap_retrans_timeout);
2381 INIT_DELAYED_WORK(&chan->monitor_timer, l2cap_monitor_timeout);
2382 INIT_DELAYED_WORK(&chan->ack_timer, l2cap_ack_timeout);
2383
2384 skb_queue_head_init(&chan->srej_q);
2385
2386 INIT_LIST_HEAD(&chan->srej_l);
2387 err = l2cap_seq_list_init(&chan->srej_list, chan->tx_win);
2388 if (err < 0)
2389 return err;
2390
2391 return l2cap_seq_list_init(&chan->retrans_list, chan->remote_tx_win);
2392}
2393
2394static inline __u8 l2cap_select_mode(__u8 mode, __u16 remote_feat_mask)
2395{
2396 switch (mode) {
2397 case L2CAP_MODE_STREAMING:
2398 case L2CAP_MODE_ERTM:
2399 if (l2cap_mode_supported(mode, remote_feat_mask))
2400 return mode;
2401 /* fall through */
2402 default:
2403 return L2CAP_MODE_BASIC;
2404 }
2405}
2406
2407static inline bool __l2cap_ews_supported(struct l2cap_chan *chan)
2408{
2409 return enable_hs && chan->conn->feat_mask & L2CAP_FEAT_EXT_WINDOW;
2410}
2411
2412static inline bool __l2cap_efs_supported(struct l2cap_chan *chan)
2413{
2414 return enable_hs && chan->conn->feat_mask & L2CAP_FEAT_EXT_FLOW;
2415}
2416
2417static inline void l2cap_txwin_setup(struct l2cap_chan *chan)
2418{
2419 if (chan->tx_win > L2CAP_DEFAULT_TX_WINDOW &&
2420 __l2cap_ews_supported(chan)) {
2421 /* use extended control field */
2422 set_bit(FLAG_EXT_CTRL, &chan->flags);
2423 chan->tx_win_max = L2CAP_DEFAULT_EXT_WINDOW;
2424 } else {
2425 chan->tx_win = min_t(u16, chan->tx_win,
2426 L2CAP_DEFAULT_TX_WINDOW);
2427 chan->tx_win_max = L2CAP_DEFAULT_TX_WINDOW;
2428 }
2429}
2430
2431static int l2cap_build_conf_req(struct l2cap_chan *chan, void *data)
2432{
2433 struct l2cap_conf_req *req = data;
2434 struct l2cap_conf_rfc rfc = { .mode = chan->mode };
2435 void *ptr = req->data;
2436 u16 size;
2437
2438 BT_DBG("chan %p", chan);
2439
2440 if (chan->num_conf_req || chan->num_conf_rsp)
2441 goto done;
2442
2443 switch (chan->mode) {
2444 case L2CAP_MODE_STREAMING:
2445 case L2CAP_MODE_ERTM:
2446 if (test_bit(CONF_STATE2_DEVICE, &chan->conf_state))
2447 break;
2448
2449 if (__l2cap_efs_supported(chan))
2450 set_bit(FLAG_EFS_ENABLE, &chan->flags);
2451
2452 /* fall through */
2453 default:
2454 chan->mode = l2cap_select_mode(rfc.mode, chan->conn->feat_mask);
2455 break;
2456 }
2457
2458done:
2459 if (chan->imtu != L2CAP_DEFAULT_MTU)
2460 l2cap_add_conf_opt(&ptr, L2CAP_CONF_MTU, 2, chan->imtu);
2461
2462 switch (chan->mode) {
2463 case L2CAP_MODE_BASIC:
2464 if (!(chan->conn->feat_mask & L2CAP_FEAT_ERTM) &&
2465 !(chan->conn->feat_mask & L2CAP_FEAT_STREAMING))
2466 break;
2467
2468 rfc.mode = L2CAP_MODE_BASIC;
2469 rfc.txwin_size = 0;
2470 rfc.max_transmit = 0;
2471 rfc.retrans_timeout = 0;
2472 rfc.monitor_timeout = 0;
2473 rfc.max_pdu_size = 0;
2474
2475 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
2476 (unsigned long) &rfc);
2477 break;
2478
2479 case L2CAP_MODE_ERTM:
2480 rfc.mode = L2CAP_MODE_ERTM;
2481 rfc.max_transmit = chan->max_tx;
2482 rfc.retrans_timeout = 0;
2483 rfc.monitor_timeout = 0;
2484
2485 size = min_t(u16, L2CAP_DEFAULT_MAX_PDU_SIZE, chan->conn->mtu -
2486 L2CAP_EXT_HDR_SIZE -
2487 L2CAP_SDULEN_SIZE -
2488 L2CAP_FCS_SIZE);
2489 rfc.max_pdu_size = cpu_to_le16(size);
2490
2491 l2cap_txwin_setup(chan);
2492
2493 rfc.txwin_size = min_t(u16, chan->tx_win,
2494 L2CAP_DEFAULT_TX_WINDOW);
2495
2496 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
2497 (unsigned long) &rfc);
2498
2499 if (test_bit(FLAG_EFS_ENABLE, &chan->flags))
2500 l2cap_add_opt_efs(&ptr, chan);
2501
2502 if (!(chan->conn->feat_mask & L2CAP_FEAT_FCS))
2503 break;
2504
2505 if (chan->fcs == L2CAP_FCS_NONE ||
2506 test_bit(CONF_NO_FCS_RECV, &chan->conf_state)) {
2507 chan->fcs = L2CAP_FCS_NONE;
2508 l2cap_add_conf_opt(&ptr, L2CAP_CONF_FCS, 1, chan->fcs);
2509 }
2510
2511 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
2512 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EWS, 2,
2513 chan->tx_win);
2514 break;
2515
2516 case L2CAP_MODE_STREAMING:
2517 rfc.mode = L2CAP_MODE_STREAMING;
2518 rfc.txwin_size = 0;
2519 rfc.max_transmit = 0;
2520 rfc.retrans_timeout = 0;
2521 rfc.monitor_timeout = 0;
2522
2523 size = min_t(u16, L2CAP_DEFAULT_MAX_PDU_SIZE, chan->conn->mtu -
2524 L2CAP_EXT_HDR_SIZE -
2525 L2CAP_SDULEN_SIZE -
2526 L2CAP_FCS_SIZE);
2527 rfc.max_pdu_size = cpu_to_le16(size);
2528
2529 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
2530 (unsigned long) &rfc);
2531
2532 if (test_bit(FLAG_EFS_ENABLE, &chan->flags))
2533 l2cap_add_opt_efs(&ptr, chan);
2534
2535 if (!(chan->conn->feat_mask & L2CAP_FEAT_FCS))
2536 break;
2537
2538 if (chan->fcs == L2CAP_FCS_NONE ||
2539 test_bit(CONF_NO_FCS_RECV, &chan->conf_state)) {
2540 chan->fcs = L2CAP_FCS_NONE;
2541 l2cap_add_conf_opt(&ptr, L2CAP_CONF_FCS, 1, chan->fcs);
2542 }
2543 break;
2544 }
2545
2546 req->dcid = cpu_to_le16(chan->dcid);
2547 req->flags = cpu_to_le16(0);
2548
2549 return ptr - data;
2550}
2551
2552static int l2cap_parse_conf_req(struct l2cap_chan *chan, void *data)
2553{
2554 struct l2cap_conf_rsp *rsp = data;
2555 void *ptr = rsp->data;
2556 void *req = chan->conf_req;
2557 int len = chan->conf_len;
2558 int type, hint, olen;
2559 unsigned long val;
2560 struct l2cap_conf_rfc rfc = { .mode = L2CAP_MODE_BASIC };
2561 struct l2cap_conf_efs efs;
2562 u8 remote_efs = 0;
2563 u16 mtu = L2CAP_DEFAULT_MTU;
2564 u16 result = L2CAP_CONF_SUCCESS;
2565 u16 size;
2566
2567 BT_DBG("chan %p", chan);
2568
2569 while (len >= L2CAP_CONF_OPT_SIZE) {
2570 len -= l2cap_get_conf_opt(&req, &type, &olen, &val);
2571
2572 hint = type & L2CAP_CONF_HINT;
2573 type &= L2CAP_CONF_MASK;
2574
2575 switch (type) {
2576 case L2CAP_CONF_MTU:
2577 mtu = val;
2578 break;
2579
2580 case L2CAP_CONF_FLUSH_TO:
2581 chan->flush_to = val;
2582 break;
2583
2584 case L2CAP_CONF_QOS:
2585 break;
2586
2587 case L2CAP_CONF_RFC:
2588 if (olen == sizeof(rfc))
2589 memcpy(&rfc, (void *) val, olen);
2590 break;
2591
2592 case L2CAP_CONF_FCS:
2593 if (val == L2CAP_FCS_NONE)
2594 set_bit(CONF_NO_FCS_RECV, &chan->conf_state);
2595 break;
2596
2597 case L2CAP_CONF_EFS:
2598 remote_efs = 1;
2599 if (olen == sizeof(efs))
2600 memcpy(&efs, (void *) val, olen);
2601 break;
2602
2603 case L2CAP_CONF_EWS:
2604 if (!enable_hs)
2605 return -ECONNREFUSED;
2606
2607 set_bit(FLAG_EXT_CTRL, &chan->flags);
2608 set_bit(CONF_EWS_RECV, &chan->conf_state);
2609 chan->tx_win_max = L2CAP_DEFAULT_EXT_WINDOW;
2610 chan->remote_tx_win = val;
2611 break;
2612
2613 default:
2614 if (hint)
2615 break;
2616
2617 result = L2CAP_CONF_UNKNOWN;
2618 *((u8 *) ptr++) = type;
2619 break;
2620 }
2621 }
2622
2623 if (chan->num_conf_rsp || chan->num_conf_req > 1)
2624 goto done;
2625
2626 switch (chan->mode) {
2627 case L2CAP_MODE_STREAMING:
2628 case L2CAP_MODE_ERTM:
2629 if (!test_bit(CONF_STATE2_DEVICE, &chan->conf_state)) {
2630 chan->mode = l2cap_select_mode(rfc.mode,
2631 chan->conn->feat_mask);
2632 break;
2633 }
2634
2635 if (remote_efs) {
2636 if (__l2cap_efs_supported(chan))
2637 set_bit(FLAG_EFS_ENABLE, &chan->flags);
2638 else
2639 return -ECONNREFUSED;
2640 }
2641
2642 if (chan->mode != rfc.mode)
2643 return -ECONNREFUSED;
2644
2645 break;
2646 }
2647
2648done:
2649 if (chan->mode != rfc.mode) {
2650 result = L2CAP_CONF_UNACCEPT;
2651 rfc.mode = chan->mode;
2652
2653 if (chan->num_conf_rsp == 1)
2654 return -ECONNREFUSED;
2655
2656 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC,
2657 sizeof(rfc), (unsigned long) &rfc);
2658 }
2659
2660 if (result == L2CAP_CONF_SUCCESS) {
2661 /* Configure output options and let the other side know
2662 * which ones we don't like. */
2663
2664 if (mtu < L2CAP_DEFAULT_MIN_MTU)
2665 result = L2CAP_CONF_UNACCEPT;
2666 else {
2667 chan->omtu = mtu;
2668 set_bit(CONF_MTU_DONE, &chan->conf_state);
2669 }
2670 l2cap_add_conf_opt(&ptr, L2CAP_CONF_MTU, 2, chan->omtu);
2671
2672 if (remote_efs) {
2673 if (chan->local_stype != L2CAP_SERV_NOTRAFIC &&
2674 efs.stype != L2CAP_SERV_NOTRAFIC &&
2675 efs.stype != chan->local_stype) {
2676
2677 result = L2CAP_CONF_UNACCEPT;
2678
2679 if (chan->num_conf_req >= 1)
2680 return -ECONNREFUSED;
2681
2682 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EFS,
2683 sizeof(efs),
2684 (unsigned long) &efs);
2685 } else {
2686 /* Send PENDING Conf Rsp */
2687 result = L2CAP_CONF_PENDING;
2688 set_bit(CONF_LOC_CONF_PEND, &chan->conf_state);
2689 }
2690 }
2691
2692 switch (rfc.mode) {
2693 case L2CAP_MODE_BASIC:
2694 chan->fcs = L2CAP_FCS_NONE;
2695 set_bit(CONF_MODE_DONE, &chan->conf_state);
2696 break;
2697
2698 case L2CAP_MODE_ERTM:
2699 if (!test_bit(CONF_EWS_RECV, &chan->conf_state))
2700 chan->remote_tx_win = rfc.txwin_size;
2701 else
2702 rfc.txwin_size = L2CAP_DEFAULT_TX_WINDOW;
2703
2704 chan->remote_max_tx = rfc.max_transmit;
2705
2706 size = min_t(u16, le16_to_cpu(rfc.max_pdu_size),
2707 chan->conn->mtu -
2708 L2CAP_EXT_HDR_SIZE -
2709 L2CAP_SDULEN_SIZE -
2710 L2CAP_FCS_SIZE);
2711 rfc.max_pdu_size = cpu_to_le16(size);
2712 chan->remote_mps = size;
2713
2714 rfc.retrans_timeout =
2715 __constant_cpu_to_le16(L2CAP_DEFAULT_RETRANS_TO);
2716 rfc.monitor_timeout =
2717 __constant_cpu_to_le16(L2CAP_DEFAULT_MONITOR_TO);
2718
2719 set_bit(CONF_MODE_DONE, &chan->conf_state);
2720
2721 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC,
2722 sizeof(rfc), (unsigned long) &rfc);
2723
2724 if (test_bit(FLAG_EFS_ENABLE, &chan->flags)) {
2725 chan->remote_id = efs.id;
2726 chan->remote_stype = efs.stype;
2727 chan->remote_msdu = le16_to_cpu(efs.msdu);
2728 chan->remote_flush_to =
2729 le32_to_cpu(efs.flush_to);
2730 chan->remote_acc_lat =
2731 le32_to_cpu(efs.acc_lat);
2732 chan->remote_sdu_itime =
2733 le32_to_cpu(efs.sdu_itime);
2734 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EFS,
2735 sizeof(efs), (unsigned long) &efs);
2736 }
2737 break;
2738
2739 case L2CAP_MODE_STREAMING:
2740 size = min_t(u16, le16_to_cpu(rfc.max_pdu_size),
2741 chan->conn->mtu -
2742 L2CAP_EXT_HDR_SIZE -
2743 L2CAP_SDULEN_SIZE -
2744 L2CAP_FCS_SIZE);
2745 rfc.max_pdu_size = cpu_to_le16(size);
2746 chan->remote_mps = size;
2747
2748 set_bit(CONF_MODE_DONE, &chan->conf_state);
2749
2750 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC,
2751 sizeof(rfc), (unsigned long) &rfc);
2752
2753 break;
2754
2755 default:
2756 result = L2CAP_CONF_UNACCEPT;
2757
2758 memset(&rfc, 0, sizeof(rfc));
2759 rfc.mode = chan->mode;
2760 }
2761
2762 if (result == L2CAP_CONF_SUCCESS)
2763 set_bit(CONF_OUTPUT_DONE, &chan->conf_state);
2764 }
2765 rsp->scid = cpu_to_le16(chan->dcid);
2766 rsp->result = cpu_to_le16(result);
2767 rsp->flags = cpu_to_le16(0x0000);
2768
2769 return ptr - data;
2770}
2771
2772static int l2cap_parse_conf_rsp(struct l2cap_chan *chan, void *rsp, int len, void *data, u16 *result)
2773{
2774 struct l2cap_conf_req *req = data;
2775 void *ptr = req->data;
2776 int type, olen;
2777 unsigned long val;
2778 struct l2cap_conf_rfc rfc = { .mode = L2CAP_MODE_BASIC };
2779 struct l2cap_conf_efs efs;
2780
2781 BT_DBG("chan %p, rsp %p, len %d, req %p", chan, rsp, len, data);
2782
2783 while (len >= L2CAP_CONF_OPT_SIZE) {
2784 len -= l2cap_get_conf_opt(&rsp, &type, &olen, &val);
2785
2786 switch (type) {
2787 case L2CAP_CONF_MTU:
2788 if (val < L2CAP_DEFAULT_MIN_MTU) {
2789 *result = L2CAP_CONF_UNACCEPT;
2790 chan->imtu = L2CAP_DEFAULT_MIN_MTU;
2791 } else
2792 chan->imtu = val;
2793 l2cap_add_conf_opt(&ptr, L2CAP_CONF_MTU, 2, chan->imtu);
2794 break;
2795
2796 case L2CAP_CONF_FLUSH_TO:
2797 chan->flush_to = val;
2798 l2cap_add_conf_opt(&ptr, L2CAP_CONF_FLUSH_TO,
2799 2, chan->flush_to);
2800 break;
2801
2802 case L2CAP_CONF_RFC:
2803 if (olen == sizeof(rfc))
2804 memcpy(&rfc, (void *)val, olen);
2805
2806 if (test_bit(CONF_STATE2_DEVICE, &chan->conf_state) &&
2807 rfc.mode != chan->mode)
2808 return -ECONNREFUSED;
2809
2810 chan->fcs = 0;
2811
2812 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC,
2813 sizeof(rfc), (unsigned long) &rfc);
2814 break;
2815
2816 case L2CAP_CONF_EWS:
2817 chan->tx_win = min_t(u16, val,
2818 L2CAP_DEFAULT_EXT_WINDOW);
2819 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EWS, 2,
2820 chan->tx_win);
2821 break;
2822
2823 case L2CAP_CONF_EFS:
2824 if (olen == sizeof(efs))
2825 memcpy(&efs, (void *)val, olen);
2826
2827 if (chan->local_stype != L2CAP_SERV_NOTRAFIC &&
2828 efs.stype != L2CAP_SERV_NOTRAFIC &&
2829 efs.stype != chan->local_stype)
2830 return -ECONNREFUSED;
2831
2832 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EFS,
2833 sizeof(efs), (unsigned long) &efs);
2834 break;
2835 }
2836 }
2837
2838 if (chan->mode == L2CAP_MODE_BASIC && chan->mode != rfc.mode)
2839 return -ECONNREFUSED;
2840
2841 chan->mode = rfc.mode;
2842
2843 if (*result == L2CAP_CONF_SUCCESS || *result == L2CAP_CONF_PENDING) {
2844 switch (rfc.mode) {
2845 case L2CAP_MODE_ERTM:
2846 chan->retrans_timeout = le16_to_cpu(rfc.retrans_timeout);
2847 chan->monitor_timeout = le16_to_cpu(rfc.monitor_timeout);
2848 chan->mps = le16_to_cpu(rfc.max_pdu_size);
2849
2850 if (test_bit(FLAG_EFS_ENABLE, &chan->flags)) {
2851 chan->local_msdu = le16_to_cpu(efs.msdu);
2852 chan->local_sdu_itime =
2853 le32_to_cpu(efs.sdu_itime);
2854 chan->local_acc_lat = le32_to_cpu(efs.acc_lat);
2855 chan->local_flush_to =
2856 le32_to_cpu(efs.flush_to);
2857 }
2858 break;
2859
2860 case L2CAP_MODE_STREAMING:
2861 chan->mps = le16_to_cpu(rfc.max_pdu_size);
2862 }
2863 }
2864
2865 req->dcid = cpu_to_le16(chan->dcid);
2866 req->flags = cpu_to_le16(0x0000);
2867
2868 return ptr - data;
2869}
2870
2871static int l2cap_build_conf_rsp(struct l2cap_chan *chan, void *data, u16 result, u16 flags)
2872{
2873 struct l2cap_conf_rsp *rsp = data;
2874 void *ptr = rsp->data;
2875
2876 BT_DBG("chan %p", chan);
2877
2878 rsp->scid = cpu_to_le16(chan->dcid);
2879 rsp->result = cpu_to_le16(result);
2880 rsp->flags = cpu_to_le16(flags);
2881
2882 return ptr - data;
2883}
2884
2885void __l2cap_connect_rsp_defer(struct l2cap_chan *chan)
2886{
2887 struct l2cap_conn_rsp rsp;
2888 struct l2cap_conn *conn = chan->conn;
2889 u8 buf[128];
2890
2891 rsp.scid = cpu_to_le16(chan->dcid);
2892 rsp.dcid = cpu_to_le16(chan->scid);
2893 rsp.result = cpu_to_le16(L2CAP_CR_SUCCESS);
2894 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
2895 l2cap_send_cmd(conn, chan->ident,
2896 L2CAP_CONN_RSP, sizeof(rsp), &rsp);
2897
2898 if (test_and_set_bit(CONF_REQ_SENT, &chan->conf_state))
2899 return;
2900
2901 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
2902 l2cap_build_conf_req(chan, buf), buf);
2903 chan->num_conf_req++;
2904}
2905
2906static void l2cap_conf_rfc_get(struct l2cap_chan *chan, void *rsp, int len)
2907{
2908 int type, olen;
2909 unsigned long val;
2910 struct l2cap_conf_rfc rfc;
2911
2912 BT_DBG("chan %p, rsp %p, len %d", chan, rsp, len);
2913
2914 if ((chan->mode != L2CAP_MODE_ERTM) && (chan->mode != L2CAP_MODE_STREAMING))
2915 return;
2916
2917 while (len >= L2CAP_CONF_OPT_SIZE) {
2918 len -= l2cap_get_conf_opt(&rsp, &type, &olen, &val);
2919
2920 if (type != L2CAP_CONF_RFC)
2921 continue;
2922
2923 if (olen != sizeof(rfc))
2924 break;
2925
2926 memcpy(&rfc, (void *)val, olen);
2927 goto done;
2928 }
2929
2930 /* Use sane default values in case a misbehaving remote device
2931 * did not send an RFC option.
2932 */
2933 rfc.mode = chan->mode;
2934 rfc.retrans_timeout = cpu_to_le16(L2CAP_DEFAULT_RETRANS_TO);
2935 rfc.monitor_timeout = cpu_to_le16(L2CAP_DEFAULT_MONITOR_TO);
2936 rfc.max_pdu_size = cpu_to_le16(chan->imtu);
2937
2938 BT_ERR("Expected RFC option was not found, using defaults");
2939
2940done:
2941 switch (rfc.mode) {
2942 case L2CAP_MODE_ERTM:
2943 chan->retrans_timeout = le16_to_cpu(rfc.retrans_timeout);
2944 chan->monitor_timeout = le16_to_cpu(rfc.monitor_timeout);
2945 chan->mps = le16_to_cpu(rfc.max_pdu_size);
2946 break;
2947 case L2CAP_MODE_STREAMING:
2948 chan->mps = le16_to_cpu(rfc.max_pdu_size);
2949 }
2950}
2951
2952static inline int l2cap_command_rej(struct l2cap_conn *conn, struct l2cap_cmd_hdr *cmd, u8 *data)
2953{
2954 struct l2cap_cmd_rej_unk *rej = (struct l2cap_cmd_rej_unk *) data;
2955
2956 if (rej->reason != L2CAP_REJ_NOT_UNDERSTOOD)
2957 return 0;
2958
2959 if ((conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT) &&
2960 cmd->ident == conn->info_ident) {
2961 cancel_delayed_work(&conn->info_timer);
2962
2963 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
2964 conn->info_ident = 0;
2965
2966 l2cap_conn_start(conn);
2967 }
2968
2969 return 0;
2970}
2971
2972static inline int l2cap_connect_req(struct l2cap_conn *conn, struct l2cap_cmd_hdr *cmd, u8 *data)
2973{
2974 struct l2cap_conn_req *req = (struct l2cap_conn_req *) data;
2975 struct l2cap_conn_rsp rsp;
2976 struct l2cap_chan *chan = NULL, *pchan;
2977 struct sock *parent, *sk = NULL;
2978 int result, status = L2CAP_CS_NO_INFO;
2979
2980 u16 dcid = 0, scid = __le16_to_cpu(req->scid);
2981 __le16 psm = req->psm;
2982
2983 BT_DBG("psm 0x%2.2x scid 0x%4.4x", __le16_to_cpu(psm), scid);
2984
2985 /* Check if we have socket listening on psm */
2986 pchan = l2cap_global_chan_by_psm(BT_LISTEN, psm, conn->src, conn->dst);
2987 if (!pchan) {
2988 result = L2CAP_CR_BAD_PSM;
2989 goto sendresp;
2990 }
2991
2992 parent = pchan->sk;
2993
2994 mutex_lock(&conn->chan_lock);
2995 lock_sock(parent);
2996
2997 /* Check if the ACL is secure enough (if not SDP) */
2998 if (psm != cpu_to_le16(0x0001) &&
2999 !hci_conn_check_link_mode(conn->hcon)) {
3000 conn->disc_reason = HCI_ERROR_AUTH_FAILURE;
3001 result = L2CAP_CR_SEC_BLOCK;
3002 goto response;
3003 }
3004
3005 result = L2CAP_CR_NO_MEM;
3006
3007 /* Check for backlog size */
3008 if (sk_acceptq_is_full(parent)) {
3009 BT_DBG("backlog full %d", parent->sk_ack_backlog);
3010 goto response;
3011 }
3012
3013 chan = pchan->ops->new_connection(pchan->data);
3014 if (!chan)
3015 goto response;
3016
3017 sk = chan->sk;
3018
3019 /* Check if we already have channel with that dcid */
3020 if (__l2cap_get_chan_by_dcid(conn, scid)) {
3021 sock_set_flag(sk, SOCK_ZAPPED);
3022 chan->ops->close(chan->data);
3023 goto response;
3024 }
3025
3026 hci_conn_hold(conn->hcon);
3027
3028 bacpy(&bt_sk(sk)->src, conn->src);
3029 bacpy(&bt_sk(sk)->dst, conn->dst);
3030 chan->psm = psm;
3031 chan->dcid = scid;
3032
3033 bt_accept_enqueue(parent, sk);
3034
3035 __l2cap_chan_add(conn, chan);
3036
3037 dcid = chan->scid;
3038
3039 __set_chan_timer(chan, sk->sk_sndtimeo);
3040
3041 chan->ident = cmd->ident;
3042
3043 if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE) {
3044 if (l2cap_chan_check_security(chan)) {
3045 if (test_bit(BT_SK_DEFER_SETUP, &bt_sk(sk)->flags)) {
3046 __l2cap_state_change(chan, BT_CONNECT2);
3047 result = L2CAP_CR_PEND;
3048 status = L2CAP_CS_AUTHOR_PEND;
3049 parent->sk_data_ready(parent, 0);
3050 } else {
3051 __l2cap_state_change(chan, BT_CONFIG);
3052 result = L2CAP_CR_SUCCESS;
3053 status = L2CAP_CS_NO_INFO;
3054 }
3055 } else {
3056 __l2cap_state_change(chan, BT_CONNECT2);
3057 result = L2CAP_CR_PEND;
3058 status = L2CAP_CS_AUTHEN_PEND;
3059 }
3060 } else {
3061 __l2cap_state_change(chan, BT_CONNECT2);
3062 result = L2CAP_CR_PEND;
3063 status = L2CAP_CS_NO_INFO;
3064 }
3065
3066response:
3067 release_sock(parent);
3068 mutex_unlock(&conn->chan_lock);
3069
3070sendresp:
3071 rsp.scid = cpu_to_le16(scid);
3072 rsp.dcid = cpu_to_le16(dcid);
3073 rsp.result = cpu_to_le16(result);
3074 rsp.status = cpu_to_le16(status);
3075 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONN_RSP, sizeof(rsp), &rsp);
3076
3077 if (result == L2CAP_CR_PEND && status == L2CAP_CS_NO_INFO) {
3078 struct l2cap_info_req info;
3079 info.type = cpu_to_le16(L2CAP_IT_FEAT_MASK);
3080
3081 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_SENT;
3082 conn->info_ident = l2cap_get_ident(conn);
3083
3084 schedule_delayed_work(&conn->info_timer, L2CAP_INFO_TIMEOUT);
3085
3086 l2cap_send_cmd(conn, conn->info_ident,
3087 L2CAP_INFO_REQ, sizeof(info), &info);
3088 }
3089
3090 if (chan && !test_bit(CONF_REQ_SENT, &chan->conf_state) &&
3091 result == L2CAP_CR_SUCCESS) {
3092 u8 buf[128];
3093 set_bit(CONF_REQ_SENT, &chan->conf_state);
3094 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
3095 l2cap_build_conf_req(chan, buf), buf);
3096 chan->num_conf_req++;
3097 }
3098
3099 return 0;
3100}
3101
3102static inline int l2cap_connect_rsp(struct l2cap_conn *conn, struct l2cap_cmd_hdr *cmd, u8 *data)
3103{
3104 struct l2cap_conn_rsp *rsp = (struct l2cap_conn_rsp *) data;
3105 u16 scid, dcid, result, status;
3106 struct l2cap_chan *chan;
3107 u8 req[128];
3108 int err;
3109
3110 scid = __le16_to_cpu(rsp->scid);
3111 dcid = __le16_to_cpu(rsp->dcid);
3112 result = __le16_to_cpu(rsp->result);
3113 status = __le16_to_cpu(rsp->status);
3114
3115 BT_DBG("dcid 0x%4.4x scid 0x%4.4x result 0x%2.2x status 0x%2.2x",
3116 dcid, scid, result, status);
3117
3118 mutex_lock(&conn->chan_lock);
3119
3120 if (scid) {
3121 chan = __l2cap_get_chan_by_scid(conn, scid);
3122 if (!chan) {
3123 err = -EFAULT;
3124 goto unlock;
3125 }
3126 } else {
3127 chan = __l2cap_get_chan_by_ident(conn, cmd->ident);
3128 if (!chan) {
3129 err = -EFAULT;
3130 goto unlock;
3131 }
3132 }
3133
3134 err = 0;
3135
3136 l2cap_chan_lock(chan);
3137
3138 switch (result) {
3139 case L2CAP_CR_SUCCESS:
3140 l2cap_state_change(chan, BT_CONFIG);
3141 chan->ident = 0;
3142 chan->dcid = dcid;
3143 clear_bit(CONF_CONNECT_PEND, &chan->conf_state);
3144
3145 if (test_and_set_bit(CONF_REQ_SENT, &chan->conf_state))
3146 break;
3147
3148 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
3149 l2cap_build_conf_req(chan, req), req);
3150 chan->num_conf_req++;
3151 break;
3152
3153 case L2CAP_CR_PEND:
3154 set_bit(CONF_CONNECT_PEND, &chan->conf_state);
3155 break;
3156
3157 default:
3158 l2cap_chan_del(chan, ECONNREFUSED);
3159 break;
3160 }
3161
3162 l2cap_chan_unlock(chan);
3163
3164unlock:
3165 mutex_unlock(&conn->chan_lock);
3166
3167 return err;
3168}
3169
3170static inline void set_default_fcs(struct l2cap_chan *chan)
3171{
3172 /* FCS is enabled only in ERTM or streaming mode, if one or both
3173 * sides request it.
3174 */
3175 if (chan->mode != L2CAP_MODE_ERTM && chan->mode != L2CAP_MODE_STREAMING)
3176 chan->fcs = L2CAP_FCS_NONE;
3177 else if (!test_bit(CONF_NO_FCS_RECV, &chan->conf_state))
3178 chan->fcs = L2CAP_FCS_CRC16;
3179}
3180
3181static inline int l2cap_config_req(struct l2cap_conn *conn, struct l2cap_cmd_hdr *cmd, u16 cmd_len, u8 *data)
3182{
3183 struct l2cap_conf_req *req = (struct l2cap_conf_req *) data;
3184 u16 dcid, flags;
3185 u8 rsp[64];
3186 struct l2cap_chan *chan;
3187 int len, err = 0;
3188
3189 dcid = __le16_to_cpu(req->dcid);
3190 flags = __le16_to_cpu(req->flags);
3191
3192 BT_DBG("dcid 0x%4.4x flags 0x%2.2x", dcid, flags);
3193
3194 chan = l2cap_get_chan_by_scid(conn, dcid);
3195 if (!chan)
3196 return -ENOENT;
3197
3198 if (chan->state != BT_CONFIG && chan->state != BT_CONNECT2) {
3199 struct l2cap_cmd_rej_cid rej;
3200
3201 rej.reason = cpu_to_le16(L2CAP_REJ_INVALID_CID);
3202 rej.scid = cpu_to_le16(chan->scid);
3203 rej.dcid = cpu_to_le16(chan->dcid);
3204
3205 l2cap_send_cmd(conn, cmd->ident, L2CAP_COMMAND_REJ,
3206 sizeof(rej), &rej);
3207 goto unlock;
3208 }
3209
3210 /* Reject if config buffer is too small. */
3211 len = cmd_len - sizeof(*req);
3212 if (len < 0 || chan->conf_len + len > sizeof(chan->conf_req)) {
3213 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP,
3214 l2cap_build_conf_rsp(chan, rsp,
3215 L2CAP_CONF_REJECT, flags), rsp);
3216 goto unlock;
3217 }
3218
3219 /* Store config. */
3220 memcpy(chan->conf_req + chan->conf_len, req->data, len);
3221 chan->conf_len += len;
3222
3223 if (flags & 0x0001) {
3224 /* Incomplete config. Send empty response. */
3225 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP,
3226 l2cap_build_conf_rsp(chan, rsp,
3227 L2CAP_CONF_SUCCESS, 0x0001), rsp);
3228 goto unlock;
3229 }
3230
3231 /* Complete config. */
3232 len = l2cap_parse_conf_req(chan, rsp);
3233 if (len < 0) {
3234 l2cap_send_disconn_req(conn, chan, ECONNRESET);
3235 goto unlock;
3236 }
3237
3238 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP, len, rsp);
3239 chan->num_conf_rsp++;
3240
3241 /* Reset config buffer. */
3242 chan->conf_len = 0;
3243
3244 if (!test_bit(CONF_OUTPUT_DONE, &chan->conf_state))
3245 goto unlock;
3246
3247 if (test_bit(CONF_INPUT_DONE, &chan->conf_state)) {
3248 set_default_fcs(chan);
3249
3250 l2cap_state_change(chan, BT_CONNECTED);
3251
3252 if (chan->mode == L2CAP_MODE_ERTM ||
3253 chan->mode == L2CAP_MODE_STREAMING)
3254 err = l2cap_ertm_init(chan);
3255
3256 if (err < 0)
3257 l2cap_send_disconn_req(chan->conn, chan, -err);
3258 else
3259 l2cap_chan_ready(chan);
3260
3261 goto unlock;
3262 }
3263
3264 if (!test_and_set_bit(CONF_REQ_SENT, &chan->conf_state)) {
3265 u8 buf[64];
3266 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
3267 l2cap_build_conf_req(chan, buf), buf);
3268 chan->num_conf_req++;
3269 }
3270
3271 /* Got Conf Rsp PENDING from remote side and asume we sent
3272 Conf Rsp PENDING in the code above */
3273 if (test_bit(CONF_REM_CONF_PEND, &chan->conf_state) &&
3274 test_bit(CONF_LOC_CONF_PEND, &chan->conf_state)) {
3275
3276 /* check compatibility */
3277
3278 clear_bit(CONF_LOC_CONF_PEND, &chan->conf_state);
3279 set_bit(CONF_OUTPUT_DONE, &chan->conf_state);
3280
3281 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP,
3282 l2cap_build_conf_rsp(chan, rsp,
3283 L2CAP_CONF_SUCCESS, 0x0000), rsp);
3284 }
3285
3286unlock:
3287 l2cap_chan_unlock(chan);
3288 return err;
3289}
3290
3291static inline int l2cap_config_rsp(struct l2cap_conn *conn, struct l2cap_cmd_hdr *cmd, u8 *data)
3292{
3293 struct l2cap_conf_rsp *rsp = (struct l2cap_conf_rsp *)data;
3294 u16 scid, flags, result;
3295 struct l2cap_chan *chan;
3296 int len = le16_to_cpu(cmd->len) - sizeof(*rsp);
3297 int err = 0;
3298
3299 scid = __le16_to_cpu(rsp->scid);
3300 flags = __le16_to_cpu(rsp->flags);
3301 result = __le16_to_cpu(rsp->result);
3302
3303 BT_DBG("scid 0x%4.4x flags 0x%2.2x result 0x%2.2x len %d", scid, flags,
3304 result, len);
3305
3306 chan = l2cap_get_chan_by_scid(conn, scid);
3307 if (!chan)
3308 return 0;
3309
3310 switch (result) {
3311 case L2CAP_CONF_SUCCESS:
3312 l2cap_conf_rfc_get(chan, rsp->data, len);
3313 clear_bit(CONF_REM_CONF_PEND, &chan->conf_state);
3314 break;
3315
3316 case L2CAP_CONF_PENDING:
3317 set_bit(CONF_REM_CONF_PEND, &chan->conf_state);
3318
3319 if (test_bit(CONF_LOC_CONF_PEND, &chan->conf_state)) {
3320 char buf[64];
3321
3322 len = l2cap_parse_conf_rsp(chan, rsp->data, len,
3323 buf, &result);
3324 if (len < 0) {
3325 l2cap_send_disconn_req(conn, chan, ECONNRESET);
3326 goto done;
3327 }
3328
3329 /* check compatibility */
3330
3331 clear_bit(CONF_LOC_CONF_PEND, &chan->conf_state);
3332 set_bit(CONF_OUTPUT_DONE, &chan->conf_state);
3333
3334 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP,
3335 l2cap_build_conf_rsp(chan, buf,
3336 L2CAP_CONF_SUCCESS, 0x0000), buf);
3337 }
3338 goto done;
3339
3340 case L2CAP_CONF_UNACCEPT:
3341 if (chan->num_conf_rsp <= L2CAP_CONF_MAX_CONF_RSP) {
3342 char req[64];
3343
3344 if (len > sizeof(req) - sizeof(struct l2cap_conf_req)) {
3345 l2cap_send_disconn_req(conn, chan, ECONNRESET);
3346 goto done;
3347 }
3348
3349 /* throw out any old stored conf requests */
3350 result = L2CAP_CONF_SUCCESS;
3351 len = l2cap_parse_conf_rsp(chan, rsp->data, len,
3352 req, &result);
3353 if (len < 0) {
3354 l2cap_send_disconn_req(conn, chan, ECONNRESET);
3355 goto done;
3356 }
3357
3358 l2cap_send_cmd(conn, l2cap_get_ident(conn),
3359 L2CAP_CONF_REQ, len, req);
3360 chan->num_conf_req++;
3361 if (result != L2CAP_CONF_SUCCESS)
3362 goto done;
3363 break;
3364 }
3365
3366 default:
3367 l2cap_chan_set_err(chan, ECONNRESET);
3368
3369 __set_chan_timer(chan, L2CAP_DISC_REJ_TIMEOUT);
3370 l2cap_send_disconn_req(conn, chan, ECONNRESET);
3371 goto done;
3372 }
3373
3374 if (flags & 0x01)
3375 goto done;
3376
3377 set_bit(CONF_INPUT_DONE, &chan->conf_state);
3378
3379 if (test_bit(CONF_OUTPUT_DONE, &chan->conf_state)) {
3380 set_default_fcs(chan);
3381
3382 l2cap_state_change(chan, BT_CONNECTED);
3383 if (chan->mode == L2CAP_MODE_ERTM ||
3384 chan->mode == L2CAP_MODE_STREAMING)
3385 err = l2cap_ertm_init(chan);
3386
3387 if (err < 0)
3388 l2cap_send_disconn_req(chan->conn, chan, -err);
3389 else
3390 l2cap_chan_ready(chan);
3391 }
3392
3393done:
3394 l2cap_chan_unlock(chan);
3395 return err;
3396}
3397
3398static inline int l2cap_disconnect_req(struct l2cap_conn *conn, struct l2cap_cmd_hdr *cmd, u8 *data)
3399{
3400 struct l2cap_disconn_req *req = (struct l2cap_disconn_req *) data;
3401 struct l2cap_disconn_rsp rsp;
3402 u16 dcid, scid;
3403 struct l2cap_chan *chan;
3404 struct sock *sk;
3405
3406 scid = __le16_to_cpu(req->scid);
3407 dcid = __le16_to_cpu(req->dcid);
3408
3409 BT_DBG("scid 0x%4.4x dcid 0x%4.4x", scid, dcid);
3410
3411 mutex_lock(&conn->chan_lock);
3412
3413 chan = __l2cap_get_chan_by_scid(conn, dcid);
3414 if (!chan) {
3415 mutex_unlock(&conn->chan_lock);
3416 return 0;
3417 }
3418
3419 l2cap_chan_lock(chan);
3420
3421 sk = chan->sk;
3422
3423 rsp.dcid = cpu_to_le16(chan->scid);
3424 rsp.scid = cpu_to_le16(chan->dcid);
3425 l2cap_send_cmd(conn, cmd->ident, L2CAP_DISCONN_RSP, sizeof(rsp), &rsp);
3426
3427 lock_sock(sk);
3428 sk->sk_shutdown = SHUTDOWN_MASK;
3429 release_sock(sk);
3430
3431 l2cap_chan_hold(chan);
3432 l2cap_chan_del(chan, ECONNRESET);
3433
3434 l2cap_chan_unlock(chan);
3435
3436 chan->ops->close(chan->data);
3437 l2cap_chan_put(chan);
3438
3439 mutex_unlock(&conn->chan_lock);
3440
3441 return 0;
3442}
3443
3444static inline int l2cap_disconnect_rsp(struct l2cap_conn *conn, struct l2cap_cmd_hdr *cmd, u8 *data)
3445{
3446 struct l2cap_disconn_rsp *rsp = (struct l2cap_disconn_rsp *) data;
3447 u16 dcid, scid;
3448 struct l2cap_chan *chan;
3449
3450 scid = __le16_to_cpu(rsp->scid);
3451 dcid = __le16_to_cpu(rsp->dcid);
3452
3453 BT_DBG("dcid 0x%4.4x scid 0x%4.4x", dcid, scid);
3454
3455 mutex_lock(&conn->chan_lock);
3456
3457 chan = __l2cap_get_chan_by_scid(conn, scid);
3458 if (!chan) {
3459 mutex_unlock(&conn->chan_lock);
3460 return 0;
3461 }
3462
3463 l2cap_chan_lock(chan);
3464
3465 l2cap_chan_hold(chan);
3466 l2cap_chan_del(chan, 0);
3467
3468 l2cap_chan_unlock(chan);
3469
3470 chan->ops->close(chan->data);
3471 l2cap_chan_put(chan);
3472
3473 mutex_unlock(&conn->chan_lock);
3474
3475 return 0;
3476}
3477
3478static inline int l2cap_information_req(struct l2cap_conn *conn, struct l2cap_cmd_hdr *cmd, u8 *data)
3479{
3480 struct l2cap_info_req *req = (struct l2cap_info_req *) data;
3481 u16 type;
3482
3483 type = __le16_to_cpu(req->type);
3484
3485 BT_DBG("type 0x%4.4x", type);
3486
3487 if (type == L2CAP_IT_FEAT_MASK) {
3488 u8 buf[8];
3489 u32 feat_mask = l2cap_feat_mask;
3490 struct l2cap_info_rsp *rsp = (struct l2cap_info_rsp *) buf;
3491 rsp->type = cpu_to_le16(L2CAP_IT_FEAT_MASK);
3492 rsp->result = cpu_to_le16(L2CAP_IR_SUCCESS);
3493 if (!disable_ertm)
3494 feat_mask |= L2CAP_FEAT_ERTM | L2CAP_FEAT_STREAMING
3495 | L2CAP_FEAT_FCS;
3496 if (enable_hs)
3497 feat_mask |= L2CAP_FEAT_EXT_FLOW
3498 | L2CAP_FEAT_EXT_WINDOW;
3499
3500 put_unaligned_le32(feat_mask, rsp->data);
3501 l2cap_send_cmd(conn, cmd->ident,
3502 L2CAP_INFO_RSP, sizeof(buf), buf);
3503 } else if (type == L2CAP_IT_FIXED_CHAN) {
3504 u8 buf[12];
3505 struct l2cap_info_rsp *rsp = (struct l2cap_info_rsp *) buf;
3506
3507 if (enable_hs)
3508 l2cap_fixed_chan[0] |= L2CAP_FC_A2MP;
3509 else
3510 l2cap_fixed_chan[0] &= ~L2CAP_FC_A2MP;
3511
3512 rsp->type = cpu_to_le16(L2CAP_IT_FIXED_CHAN);
3513 rsp->result = cpu_to_le16(L2CAP_IR_SUCCESS);
3514 memcpy(rsp->data, l2cap_fixed_chan, sizeof(l2cap_fixed_chan));
3515 l2cap_send_cmd(conn, cmd->ident,
3516 L2CAP_INFO_RSP, sizeof(buf), buf);
3517 } else {
3518 struct l2cap_info_rsp rsp;
3519 rsp.type = cpu_to_le16(type);
3520 rsp.result = cpu_to_le16(L2CAP_IR_NOTSUPP);
3521 l2cap_send_cmd(conn, cmd->ident,
3522 L2CAP_INFO_RSP, sizeof(rsp), &rsp);
3523 }
3524
3525 return 0;
3526}
3527
3528static inline int l2cap_information_rsp(struct l2cap_conn *conn, struct l2cap_cmd_hdr *cmd, u8 *data)
3529{
3530 struct l2cap_info_rsp *rsp = (struct l2cap_info_rsp *) data;
3531 u16 type, result;
3532
3533 type = __le16_to_cpu(rsp->type);
3534 result = __le16_to_cpu(rsp->result);
3535
3536 BT_DBG("type 0x%4.4x result 0x%2.2x", type, result);
3537
3538 /* L2CAP Info req/rsp are unbound to channels, add extra checks */
3539 if (cmd->ident != conn->info_ident ||
3540 conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE)
3541 return 0;
3542
3543 cancel_delayed_work(&conn->info_timer);
3544
3545 if (result != L2CAP_IR_SUCCESS) {
3546 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
3547 conn->info_ident = 0;
3548
3549 l2cap_conn_start(conn);
3550
3551 return 0;
3552 }
3553
3554 switch (type) {
3555 case L2CAP_IT_FEAT_MASK:
3556 conn->feat_mask = get_unaligned_le32(rsp->data);
3557
3558 if (conn->feat_mask & L2CAP_FEAT_FIXED_CHAN) {
3559 struct l2cap_info_req req;
3560 req.type = cpu_to_le16(L2CAP_IT_FIXED_CHAN);
3561
3562 conn->info_ident = l2cap_get_ident(conn);
3563
3564 l2cap_send_cmd(conn, conn->info_ident,
3565 L2CAP_INFO_REQ, sizeof(req), &req);
3566 } else {
3567 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
3568 conn->info_ident = 0;
3569
3570 l2cap_conn_start(conn);
3571 }
3572 break;
3573
3574 case L2CAP_IT_FIXED_CHAN:
3575 conn->fixed_chan_mask = rsp->data[0];
3576 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
3577 conn->info_ident = 0;
3578
3579 l2cap_conn_start(conn);
3580 break;
3581 }
3582
3583 return 0;
3584}
3585
3586static inline int l2cap_create_channel_req(struct l2cap_conn *conn,
3587 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
3588 void *data)
3589{
3590 struct l2cap_create_chan_req *req = data;
3591 struct l2cap_create_chan_rsp rsp;
3592 u16 psm, scid;
3593
3594 if (cmd_len != sizeof(*req))
3595 return -EPROTO;
3596
3597 if (!enable_hs)
3598 return -EINVAL;
3599
3600 psm = le16_to_cpu(req->psm);
3601 scid = le16_to_cpu(req->scid);
3602
3603 BT_DBG("psm %d, scid %d, amp_id %d", psm, scid, req->amp_id);
3604
3605 /* Placeholder: Always reject */
3606 rsp.dcid = 0;
3607 rsp.scid = cpu_to_le16(scid);
3608 rsp.result = __constant_cpu_to_le16(L2CAP_CR_NO_MEM);
3609 rsp.status = __constant_cpu_to_le16(L2CAP_CS_NO_INFO);
3610
3611 l2cap_send_cmd(conn, cmd->ident, L2CAP_CREATE_CHAN_RSP,
3612 sizeof(rsp), &rsp);
3613
3614 return 0;
3615}
3616
3617static inline int l2cap_create_channel_rsp(struct l2cap_conn *conn,
3618 struct l2cap_cmd_hdr *cmd, void *data)
3619{
3620 BT_DBG("conn %p", conn);
3621
3622 return l2cap_connect_rsp(conn, cmd, data);
3623}
3624
3625static void l2cap_send_move_chan_rsp(struct l2cap_conn *conn, u8 ident,
3626 u16 icid, u16 result)
3627{
3628 struct l2cap_move_chan_rsp rsp;
3629
3630 BT_DBG("icid %d, result %d", icid, result);
3631
3632 rsp.icid = cpu_to_le16(icid);
3633 rsp.result = cpu_to_le16(result);
3634
3635 l2cap_send_cmd(conn, ident, L2CAP_MOVE_CHAN_RSP, sizeof(rsp), &rsp);
3636}
3637
3638static void l2cap_send_move_chan_cfm(struct l2cap_conn *conn,
3639 struct l2cap_chan *chan, u16 icid, u16 result)
3640{
3641 struct l2cap_move_chan_cfm cfm;
3642 u8 ident;
3643
3644 BT_DBG("icid %d, result %d", icid, result);
3645
3646 ident = l2cap_get_ident(conn);
3647 if (chan)
3648 chan->ident = ident;
3649
3650 cfm.icid = cpu_to_le16(icid);
3651 cfm.result = cpu_to_le16(result);
3652
3653 l2cap_send_cmd(conn, ident, L2CAP_MOVE_CHAN_CFM, sizeof(cfm), &cfm);
3654}
3655
3656static void l2cap_send_move_chan_cfm_rsp(struct l2cap_conn *conn, u8 ident,
3657 u16 icid)
3658{
3659 struct l2cap_move_chan_cfm_rsp rsp;
3660
3661 BT_DBG("icid %d", icid);
3662
3663 rsp.icid = cpu_to_le16(icid);
3664 l2cap_send_cmd(conn, ident, L2CAP_MOVE_CHAN_CFM_RSP, sizeof(rsp), &rsp);
3665}
3666
3667static inline int l2cap_move_channel_req(struct l2cap_conn *conn,
3668 struct l2cap_cmd_hdr *cmd, u16 cmd_len, void *data)
3669{
3670 struct l2cap_move_chan_req *req = data;
3671 u16 icid = 0;
3672 u16 result = L2CAP_MR_NOT_ALLOWED;
3673
3674 if (cmd_len != sizeof(*req))
3675 return -EPROTO;
3676
3677 icid = le16_to_cpu(req->icid);
3678
3679 BT_DBG("icid %d, dest_amp_id %d", icid, req->dest_amp_id);
3680
3681 if (!enable_hs)
3682 return -EINVAL;
3683
3684 /* Placeholder: Always refuse */
3685 l2cap_send_move_chan_rsp(conn, cmd->ident, icid, result);
3686
3687 return 0;
3688}
3689
3690static inline int l2cap_move_channel_rsp(struct l2cap_conn *conn,
3691 struct l2cap_cmd_hdr *cmd, u16 cmd_len, void *data)
3692{
3693 struct l2cap_move_chan_rsp *rsp = data;
3694 u16 icid, result;
3695
3696 if (cmd_len != sizeof(*rsp))
3697 return -EPROTO;
3698
3699 icid = le16_to_cpu(rsp->icid);
3700 result = le16_to_cpu(rsp->result);
3701
3702 BT_DBG("icid %d, result %d", icid, result);
3703
3704 /* Placeholder: Always unconfirmed */
3705 l2cap_send_move_chan_cfm(conn, NULL, icid, L2CAP_MC_UNCONFIRMED);
3706
3707 return 0;
3708}
3709
3710static inline int l2cap_move_channel_confirm(struct l2cap_conn *conn,
3711 struct l2cap_cmd_hdr *cmd, u16 cmd_len, void *data)
3712{
3713 struct l2cap_move_chan_cfm *cfm = data;
3714 u16 icid, result;
3715
3716 if (cmd_len != sizeof(*cfm))
3717 return -EPROTO;
3718
3719 icid = le16_to_cpu(cfm->icid);
3720 result = le16_to_cpu(cfm->result);
3721
3722 BT_DBG("icid %d, result %d", icid, result);
3723
3724 l2cap_send_move_chan_cfm_rsp(conn, cmd->ident, icid);
3725
3726 return 0;
3727}
3728
3729static inline int l2cap_move_channel_confirm_rsp(struct l2cap_conn *conn,
3730 struct l2cap_cmd_hdr *cmd, u16 cmd_len, void *data)
3731{
3732 struct l2cap_move_chan_cfm_rsp *rsp = data;
3733 u16 icid;
3734
3735 if (cmd_len != sizeof(*rsp))
3736 return -EPROTO;
3737
3738 icid = le16_to_cpu(rsp->icid);
3739
3740 BT_DBG("icid %d", icid);
3741
3742 return 0;
3743}
3744
3745static inline int l2cap_check_conn_param(u16 min, u16 max, u16 latency,
3746 u16 to_multiplier)
3747{
3748 u16 max_latency;
3749
3750 if (min > max || min < 6 || max > 3200)
3751 return -EINVAL;
3752
3753 if (to_multiplier < 10 || to_multiplier > 3200)
3754 return -EINVAL;
3755
3756 if (max >= to_multiplier * 8)
3757 return -EINVAL;
3758
3759 max_latency = (to_multiplier * 8 / max) - 1;
3760 if (latency > 499 || latency > max_latency)
3761 return -EINVAL;
3762
3763 return 0;
3764}
3765
3766static inline int l2cap_conn_param_update_req(struct l2cap_conn *conn,
3767 struct l2cap_cmd_hdr *cmd, u8 *data)
3768{
3769 struct hci_conn *hcon = conn->hcon;
3770 struct l2cap_conn_param_update_req *req;
3771 struct l2cap_conn_param_update_rsp rsp;
3772 u16 min, max, latency, to_multiplier, cmd_len;
3773 int err;
3774
3775 if (!(hcon->link_mode & HCI_LM_MASTER))
3776 return -EINVAL;
3777
3778 cmd_len = __le16_to_cpu(cmd->len);
3779 if (cmd_len != sizeof(struct l2cap_conn_param_update_req))
3780 return -EPROTO;
3781
3782 req = (struct l2cap_conn_param_update_req *) data;
3783 min = __le16_to_cpu(req->min);
3784 max = __le16_to_cpu(req->max);
3785 latency = __le16_to_cpu(req->latency);
3786 to_multiplier = __le16_to_cpu(req->to_multiplier);
3787
3788 BT_DBG("min 0x%4.4x max 0x%4.4x latency: 0x%4.4x Timeout: 0x%4.4x",
3789 min, max, latency, to_multiplier);
3790
3791 memset(&rsp, 0, sizeof(rsp));
3792
3793 err = l2cap_check_conn_param(min, max, latency, to_multiplier);
3794 if (err)
3795 rsp.result = cpu_to_le16(L2CAP_CONN_PARAM_REJECTED);
3796 else
3797 rsp.result = cpu_to_le16(L2CAP_CONN_PARAM_ACCEPTED);
3798
3799 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONN_PARAM_UPDATE_RSP,
3800 sizeof(rsp), &rsp);
3801
3802 if (!err)
3803 hci_le_conn_update(hcon, min, max, latency, to_multiplier);
3804
3805 return 0;
3806}
3807
3808static inline int l2cap_bredr_sig_cmd(struct l2cap_conn *conn,
3809 struct l2cap_cmd_hdr *cmd, u16 cmd_len, u8 *data)
3810{
3811 int err = 0;
3812
3813 switch (cmd->code) {
3814 case L2CAP_COMMAND_REJ:
3815 l2cap_command_rej(conn, cmd, data);
3816 break;
3817
3818 case L2CAP_CONN_REQ:
3819 err = l2cap_connect_req(conn, cmd, data);
3820 break;
3821
3822 case L2CAP_CONN_RSP:
3823 err = l2cap_connect_rsp(conn, cmd, data);
3824 break;
3825
3826 case L2CAP_CONF_REQ:
3827 err = l2cap_config_req(conn, cmd, cmd_len, data);
3828 break;
3829
3830 case L2CAP_CONF_RSP:
3831 err = l2cap_config_rsp(conn, cmd, data);
3832 break;
3833
3834 case L2CAP_DISCONN_REQ:
3835 err = l2cap_disconnect_req(conn, cmd, data);
3836 break;
3837
3838 case L2CAP_DISCONN_RSP:
3839 err = l2cap_disconnect_rsp(conn, cmd, data);
3840 break;
3841
3842 case L2CAP_ECHO_REQ:
3843 l2cap_send_cmd(conn, cmd->ident, L2CAP_ECHO_RSP, cmd_len, data);
3844 break;
3845
3846 case L2CAP_ECHO_RSP:
3847 break;
3848
3849 case L2CAP_INFO_REQ:
3850 err = l2cap_information_req(conn, cmd, data);
3851 break;
3852
3853 case L2CAP_INFO_RSP:
3854 err = l2cap_information_rsp(conn, cmd, data);
3855 break;
3856
3857 case L2CAP_CREATE_CHAN_REQ:
3858 err = l2cap_create_channel_req(conn, cmd, cmd_len, data);
3859 break;
3860
3861 case L2CAP_CREATE_CHAN_RSP:
3862 err = l2cap_create_channel_rsp(conn, cmd, data);
3863 break;
3864
3865 case L2CAP_MOVE_CHAN_REQ:
3866 err = l2cap_move_channel_req(conn, cmd, cmd_len, data);
3867 break;
3868
3869 case L2CAP_MOVE_CHAN_RSP:
3870 err = l2cap_move_channel_rsp(conn, cmd, cmd_len, data);
3871 break;
3872
3873 case L2CAP_MOVE_CHAN_CFM:
3874 err = l2cap_move_channel_confirm(conn, cmd, cmd_len, data);
3875 break;
3876
3877 case L2CAP_MOVE_CHAN_CFM_RSP:
3878 err = l2cap_move_channel_confirm_rsp(conn, cmd, cmd_len, data);
3879 break;
3880
3881 default:
3882 BT_ERR("Unknown BR/EDR signaling command 0x%2.2x", cmd->code);
3883 err = -EINVAL;
3884 break;
3885 }
3886
3887 return err;
3888}
3889
3890static inline int l2cap_le_sig_cmd(struct l2cap_conn *conn,
3891 struct l2cap_cmd_hdr *cmd, u8 *data)
3892{
3893 switch (cmd->code) {
3894 case L2CAP_COMMAND_REJ:
3895 return 0;
3896
3897 case L2CAP_CONN_PARAM_UPDATE_REQ:
3898 return l2cap_conn_param_update_req(conn, cmd, data);
3899
3900 case L2CAP_CONN_PARAM_UPDATE_RSP:
3901 return 0;
3902
3903 default:
3904 BT_ERR("Unknown LE signaling command 0x%2.2x", cmd->code);
3905 return -EINVAL;
3906 }
3907}
3908
3909static inline void l2cap_sig_channel(struct l2cap_conn *conn,
3910 struct sk_buff *skb)
3911{
3912 u8 *data = skb->data;
3913 int len = skb->len;
3914 struct l2cap_cmd_hdr cmd;
3915 int err;
3916
3917 l2cap_raw_recv(conn, skb);
3918
3919 while (len >= L2CAP_CMD_HDR_SIZE) {
3920 u16 cmd_len;
3921 memcpy(&cmd, data, L2CAP_CMD_HDR_SIZE);
3922 data += L2CAP_CMD_HDR_SIZE;
3923 len -= L2CAP_CMD_HDR_SIZE;
3924
3925 cmd_len = le16_to_cpu(cmd.len);
3926
3927 BT_DBG("code 0x%2.2x len %d id 0x%2.2x", cmd.code, cmd_len, cmd.ident);
3928
3929 if (cmd_len > len || !cmd.ident) {
3930 BT_DBG("corrupted command");
3931 break;
3932 }
3933
3934 if (conn->hcon->type == LE_LINK)
3935 err = l2cap_le_sig_cmd(conn, &cmd, data);
3936 else
3937 err = l2cap_bredr_sig_cmd(conn, &cmd, cmd_len, data);
3938
3939 if (err) {
3940 struct l2cap_cmd_rej_unk rej;
3941
3942 BT_ERR("Wrong link type (%d)", err);
3943
3944 /* FIXME: Map err to a valid reason */
3945 rej.reason = cpu_to_le16(L2CAP_REJ_NOT_UNDERSTOOD);
3946 l2cap_send_cmd(conn, cmd.ident, L2CAP_COMMAND_REJ, sizeof(rej), &rej);
3947 }
3948
3949 data += cmd_len;
3950 len -= cmd_len;
3951 }
3952
3953 kfree_skb(skb);
3954}
3955
3956static int l2cap_check_fcs(struct l2cap_chan *chan, struct sk_buff *skb)
3957{
3958 u16 our_fcs, rcv_fcs;
3959 int hdr_size;
3960
3961 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
3962 hdr_size = L2CAP_EXT_HDR_SIZE;
3963 else
3964 hdr_size = L2CAP_ENH_HDR_SIZE;
3965
3966 if (chan->fcs == L2CAP_FCS_CRC16) {
3967 skb_trim(skb, skb->len - L2CAP_FCS_SIZE);
3968 rcv_fcs = get_unaligned_le16(skb->data + skb->len);
3969 our_fcs = crc16(0, skb->data - hdr_size, skb->len + hdr_size);
3970
3971 if (our_fcs != rcv_fcs)
3972 return -EBADMSG;
3973 }
3974 return 0;
3975}
3976
3977static inline void l2cap_send_i_or_rr_or_rnr(struct l2cap_chan *chan)
3978{
3979 u32 control = 0;
3980
3981 chan->frames_sent = 0;
3982
3983 control |= __set_reqseq(chan, chan->buffer_seq);
3984
3985 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
3986 control |= __set_ctrl_super(chan, L2CAP_SUPER_RNR);
3987 l2cap_send_sframe(chan, control);
3988 set_bit(CONN_RNR_SENT, &chan->conn_state);
3989 }
3990
3991 if (test_bit(CONN_REMOTE_BUSY, &chan->conn_state))
3992 l2cap_retransmit_frames(chan);
3993
3994 l2cap_ertm_send(chan);
3995
3996 if (!test_bit(CONN_LOCAL_BUSY, &chan->conn_state) &&
3997 chan->frames_sent == 0) {
3998 control |= __set_ctrl_super(chan, L2CAP_SUPER_RR);
3999 l2cap_send_sframe(chan, control);
4000 }
4001}
4002
4003static int l2cap_add_to_srej_queue(struct l2cap_chan *chan, struct sk_buff *skb, u16 tx_seq, u8 sar)
4004{
4005 struct sk_buff *next_skb;
4006 int tx_seq_offset, next_tx_seq_offset;
4007
4008 bt_cb(skb)->control.txseq = tx_seq;
4009 bt_cb(skb)->control.sar = sar;
4010
4011 next_skb = skb_peek(&chan->srej_q);
4012
4013 tx_seq_offset = __seq_offset(chan, tx_seq, chan->buffer_seq);
4014
4015 while (next_skb) {
4016 if (bt_cb(next_skb)->control.txseq == tx_seq)
4017 return -EINVAL;
4018
4019 next_tx_seq_offset = __seq_offset(chan,
4020 bt_cb(next_skb)->control.txseq, chan->buffer_seq);
4021
4022 if (next_tx_seq_offset > tx_seq_offset) {
4023 __skb_queue_before(&chan->srej_q, next_skb, skb);
4024 return 0;
4025 }
4026
4027 if (skb_queue_is_last(&chan->srej_q, next_skb))
4028 next_skb = NULL;
4029 else
4030 next_skb = skb_queue_next(&chan->srej_q, next_skb);
4031 }
4032
4033 __skb_queue_tail(&chan->srej_q, skb);
4034
4035 return 0;
4036}
4037
4038static void append_skb_frag(struct sk_buff *skb,
4039 struct sk_buff *new_frag, struct sk_buff **last_frag)
4040{
4041 /* skb->len reflects data in skb as well as all fragments
4042 * skb->data_len reflects only data in fragments
4043 */
4044 if (!skb_has_frag_list(skb))
4045 skb_shinfo(skb)->frag_list = new_frag;
4046
4047 new_frag->next = NULL;
4048
4049 (*last_frag)->next = new_frag;
4050 *last_frag = new_frag;
4051
4052 skb->len += new_frag->len;
4053 skb->data_len += new_frag->len;
4054 skb->truesize += new_frag->truesize;
4055}
4056
4057static int l2cap_reassemble_sdu(struct l2cap_chan *chan, struct sk_buff *skb, u32 control)
4058{
4059 int err = -EINVAL;
4060
4061 switch (__get_ctrl_sar(chan, control)) {
4062 case L2CAP_SAR_UNSEGMENTED:
4063 if (chan->sdu)
4064 break;
4065
4066 err = chan->ops->recv(chan->data, skb);
4067 break;
4068
4069 case L2CAP_SAR_START:
4070 if (chan->sdu)
4071 break;
4072
4073 chan->sdu_len = get_unaligned_le16(skb->data);
4074 skb_pull(skb, L2CAP_SDULEN_SIZE);
4075
4076 if (chan->sdu_len > chan->imtu) {
4077 err = -EMSGSIZE;
4078 break;
4079 }
4080
4081 if (skb->len >= chan->sdu_len)
4082 break;
4083
4084 chan->sdu = skb;
4085 chan->sdu_last_frag = skb;
4086
4087 skb = NULL;
4088 err = 0;
4089 break;
4090
4091 case L2CAP_SAR_CONTINUE:
4092 if (!chan->sdu)
4093 break;
4094
4095 append_skb_frag(chan->sdu, skb,
4096 &chan->sdu_last_frag);
4097 skb = NULL;
4098
4099 if (chan->sdu->len >= chan->sdu_len)
4100 break;
4101
4102 err = 0;
4103 break;
4104
4105 case L2CAP_SAR_END:
4106 if (!chan->sdu)
4107 break;
4108
4109 append_skb_frag(chan->sdu, skb,
4110 &chan->sdu_last_frag);
4111 skb = NULL;
4112
4113 if (chan->sdu->len != chan->sdu_len)
4114 break;
4115
4116 err = chan->ops->recv(chan->data, chan->sdu);
4117
4118 if (!err) {
4119 /* Reassembly complete */
4120 chan->sdu = NULL;
4121 chan->sdu_last_frag = NULL;
4122 chan->sdu_len = 0;
4123 }
4124 break;
4125 }
4126
4127 if (err) {
4128 kfree_skb(skb);
4129 kfree_skb(chan->sdu);
4130 chan->sdu = NULL;
4131 chan->sdu_last_frag = NULL;
4132 chan->sdu_len = 0;
4133 }
4134
4135 return err;
4136}
4137
4138static void l2cap_ertm_enter_local_busy(struct l2cap_chan *chan)
4139{
4140 BT_DBG("chan %p, Enter local busy", chan);
4141
4142 set_bit(CONN_LOCAL_BUSY, &chan->conn_state);
4143 l2cap_seq_list_clear(&chan->srej_list);
4144
4145 __set_ack_timer(chan);
4146}
4147
4148static void l2cap_ertm_exit_local_busy(struct l2cap_chan *chan)
4149{
4150 u32 control;
4151
4152 if (!test_bit(CONN_RNR_SENT, &chan->conn_state))
4153 goto done;
4154
4155 control = __set_reqseq(chan, chan->buffer_seq);
4156 control |= __set_ctrl_poll(chan);
4157 control |= __set_ctrl_super(chan, L2CAP_SUPER_RR);
4158 l2cap_send_sframe(chan, control);
4159 chan->retry_count = 1;
4160
4161 __clear_retrans_timer(chan);
4162 __set_monitor_timer(chan);
4163
4164 set_bit(CONN_WAIT_F, &chan->conn_state);
4165
4166done:
4167 clear_bit(CONN_LOCAL_BUSY, &chan->conn_state);
4168 clear_bit(CONN_RNR_SENT, &chan->conn_state);
4169
4170 BT_DBG("chan %p, Exit local busy", chan);
4171}
4172
4173void l2cap_chan_busy(struct l2cap_chan *chan, int busy)
4174{
4175 if (chan->mode == L2CAP_MODE_ERTM) {
4176 if (busy)
4177 l2cap_ertm_enter_local_busy(chan);
4178 else
4179 l2cap_ertm_exit_local_busy(chan);
4180 }
4181}
4182
4183static void l2cap_check_srej_gap(struct l2cap_chan *chan, u16 tx_seq)
4184{
4185 struct sk_buff *skb;
4186 u32 control;
4187
4188 while ((skb = skb_peek(&chan->srej_q)) &&
4189 !test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
4190 int err;
4191
4192 if (bt_cb(skb)->control.txseq != tx_seq)
4193 break;
4194
4195 skb = skb_dequeue(&chan->srej_q);
4196 control = __set_ctrl_sar(chan, bt_cb(skb)->control.sar);
4197 err = l2cap_reassemble_sdu(chan, skb, control);
4198
4199 if (err < 0) {
4200 l2cap_send_disconn_req(chan->conn, chan, ECONNRESET);
4201 break;
4202 }
4203
4204 chan->buffer_seq_srej = __next_seq(chan, chan->buffer_seq_srej);
4205 tx_seq = __next_seq(chan, tx_seq);
4206 }
4207}
4208
4209static void l2cap_resend_srejframe(struct l2cap_chan *chan, u16 tx_seq)
4210{
4211 struct srej_list *l, *tmp;
4212 u32 control;
4213
4214 list_for_each_entry_safe(l, tmp, &chan->srej_l, list) {
4215 if (l->tx_seq == tx_seq) {
4216 list_del(&l->list);
4217 kfree(l);
4218 return;
4219 }
4220 control = __set_ctrl_super(chan, L2CAP_SUPER_SREJ);
4221 control |= __set_reqseq(chan, l->tx_seq);
4222 l2cap_send_sframe(chan, control);
4223 list_del(&l->list);
4224 list_add_tail(&l->list, &chan->srej_l);
4225 }
4226}
4227
4228static int l2cap_send_srejframe(struct l2cap_chan *chan, u16 tx_seq)
4229{
4230 struct srej_list *new;
4231 u32 control;
4232
4233 while (tx_seq != chan->expected_tx_seq) {
4234 control = __set_ctrl_super(chan, L2CAP_SUPER_SREJ);
4235 control |= __set_reqseq(chan, chan->expected_tx_seq);
4236 l2cap_seq_list_append(&chan->srej_list, chan->expected_tx_seq);
4237 l2cap_send_sframe(chan, control);
4238
4239 new = kzalloc(sizeof(struct srej_list), GFP_ATOMIC);
4240 if (!new)
4241 return -ENOMEM;
4242
4243 new->tx_seq = chan->expected_tx_seq;
4244
4245 chan->expected_tx_seq = __next_seq(chan, chan->expected_tx_seq);
4246
4247 list_add_tail(&new->list, &chan->srej_l);
4248 }
4249
4250 chan->expected_tx_seq = __next_seq(chan, chan->expected_tx_seq);
4251
4252 return 0;
4253}
4254
4255static inline int l2cap_data_channel_iframe(struct l2cap_chan *chan, u32 rx_control, struct sk_buff *skb)
4256{
4257 u16 tx_seq = __get_txseq(chan, rx_control);
4258 u16 req_seq = __get_reqseq(chan, rx_control);
4259 u8 sar = __get_ctrl_sar(chan, rx_control);
4260 int tx_seq_offset, expected_tx_seq_offset;
4261 int num_to_ack = (chan->tx_win/6) + 1;
4262 int err = 0;
4263
4264 BT_DBG("chan %p len %d tx_seq %d rx_control 0x%8.8x", chan, skb->len,
4265 tx_seq, rx_control);
4266
4267 if (__is_ctrl_final(chan, rx_control) &&
4268 test_bit(CONN_WAIT_F, &chan->conn_state)) {
4269 __clear_monitor_timer(chan);
4270 if (chan->unacked_frames > 0)
4271 __set_retrans_timer(chan);
4272 clear_bit(CONN_WAIT_F, &chan->conn_state);
4273 }
4274
4275 chan->expected_ack_seq = req_seq;
4276 l2cap_drop_acked_frames(chan);
4277
4278 tx_seq_offset = __seq_offset(chan, tx_seq, chan->buffer_seq);
4279
4280 /* invalid tx_seq */
4281 if (tx_seq_offset >= chan->tx_win) {
4282 l2cap_send_disconn_req(chan->conn, chan, ECONNRESET);
4283 goto drop;
4284 }
4285
4286 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
4287 if (!test_bit(CONN_RNR_SENT, &chan->conn_state))
4288 l2cap_send_ack(chan);
4289 goto drop;
4290 }
4291
4292 if (tx_seq == chan->expected_tx_seq)
4293 goto expected;
4294
4295 if (test_bit(CONN_SREJ_SENT, &chan->conn_state)) {
4296 struct srej_list *first;
4297
4298 first = list_first_entry(&chan->srej_l,
4299 struct srej_list, list);
4300 if (tx_seq == first->tx_seq) {
4301 l2cap_add_to_srej_queue(chan, skb, tx_seq, sar);
4302 l2cap_check_srej_gap(chan, tx_seq);
4303
4304 list_del(&first->list);
4305 kfree(first);
4306
4307 if (list_empty(&chan->srej_l)) {
4308 chan->buffer_seq = chan->buffer_seq_srej;
4309 clear_bit(CONN_SREJ_SENT, &chan->conn_state);
4310 l2cap_send_ack(chan);
4311 BT_DBG("chan %p, Exit SREJ_SENT", chan);
4312 }
4313 } else {
4314 struct srej_list *l;
4315
4316 /* duplicated tx_seq */
4317 if (l2cap_add_to_srej_queue(chan, skb, tx_seq, sar) < 0)
4318 goto drop;
4319
4320 list_for_each_entry(l, &chan->srej_l, list) {
4321 if (l->tx_seq == tx_seq) {
4322 l2cap_resend_srejframe(chan, tx_seq);
4323 return 0;
4324 }
4325 }
4326
4327 err = l2cap_send_srejframe(chan, tx_seq);
4328 if (err < 0) {
4329 l2cap_send_disconn_req(chan->conn, chan, -err);
4330 return err;
4331 }
4332 }
4333 } else {
4334 expected_tx_seq_offset = __seq_offset(chan,
4335 chan->expected_tx_seq, chan->buffer_seq);
4336
4337 /* duplicated tx_seq */
4338 if (tx_seq_offset < expected_tx_seq_offset)
4339 goto drop;
4340
4341 set_bit(CONN_SREJ_SENT, &chan->conn_state);
4342
4343 BT_DBG("chan %p, Enter SREJ", chan);
4344
4345 INIT_LIST_HEAD(&chan->srej_l);
4346 chan->buffer_seq_srej = chan->buffer_seq;
4347
4348 __skb_queue_head_init(&chan->srej_q);
4349 l2cap_add_to_srej_queue(chan, skb, tx_seq, sar);
4350
4351 /* Set P-bit only if there are some I-frames to ack. */
4352 if (__clear_ack_timer(chan))
4353 set_bit(CONN_SEND_PBIT, &chan->conn_state);
4354
4355 err = l2cap_send_srejframe(chan, tx_seq);
4356 if (err < 0) {
4357 l2cap_send_disconn_req(chan->conn, chan, -err);
4358 return err;
4359 }
4360 }
4361 return 0;
4362
4363expected:
4364 chan->expected_tx_seq = __next_seq(chan, chan->expected_tx_seq);
4365
4366 if (test_bit(CONN_SREJ_SENT, &chan->conn_state)) {
4367 bt_cb(skb)->control.txseq = tx_seq;
4368 bt_cb(skb)->control.sar = sar;
4369 __skb_queue_tail(&chan->srej_q, skb);
4370 return 0;
4371 }
4372
4373 err = l2cap_reassemble_sdu(chan, skb, rx_control);
4374 chan->buffer_seq = __next_seq(chan, chan->buffer_seq);
4375
4376 if (err < 0) {
4377 l2cap_send_disconn_req(chan->conn, chan, ECONNRESET);
4378 return err;
4379 }
4380
4381 if (__is_ctrl_final(chan, rx_control)) {
4382 if (!test_and_clear_bit(CONN_REJ_ACT, &chan->conn_state))
4383 l2cap_retransmit_frames(chan);
4384 }
4385
4386
4387 chan->num_acked = (chan->num_acked + 1) % num_to_ack;
4388 if (chan->num_acked == num_to_ack - 1)
4389 l2cap_send_ack(chan);
4390 else
4391 __set_ack_timer(chan);
4392
4393 return 0;
4394
4395drop:
4396 kfree_skb(skb);
4397 return 0;
4398}
4399
4400static inline void l2cap_data_channel_rrframe(struct l2cap_chan *chan, u32 rx_control)
4401{
4402 BT_DBG("chan %p, req_seq %d ctrl 0x%8.8x", chan,
4403 __get_reqseq(chan, rx_control), rx_control);
4404
4405 chan->expected_ack_seq = __get_reqseq(chan, rx_control);
4406 l2cap_drop_acked_frames(chan);
4407
4408 if (__is_ctrl_poll(chan, rx_control)) {
4409 set_bit(CONN_SEND_FBIT, &chan->conn_state);
4410 if (test_bit(CONN_SREJ_SENT, &chan->conn_state)) {
4411 if (test_bit(CONN_REMOTE_BUSY, &chan->conn_state) &&
4412 (chan->unacked_frames > 0))
4413 __set_retrans_timer(chan);
4414
4415 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
4416 l2cap_send_srejtail(chan);
4417 } else {
4418 l2cap_send_i_or_rr_or_rnr(chan);
4419 }
4420
4421 } else if (__is_ctrl_final(chan, rx_control)) {
4422 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
4423
4424 if (!test_and_clear_bit(CONN_REJ_ACT, &chan->conn_state))
4425 l2cap_retransmit_frames(chan);
4426
4427 } else {
4428 if (test_bit(CONN_REMOTE_BUSY, &chan->conn_state) &&
4429 (chan->unacked_frames > 0))
4430 __set_retrans_timer(chan);
4431
4432 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
4433 if (test_bit(CONN_SREJ_SENT, &chan->conn_state))
4434 l2cap_send_ack(chan);
4435 else
4436 l2cap_ertm_send(chan);
4437 }
4438}
4439
4440static inline void l2cap_data_channel_rejframe(struct l2cap_chan *chan, u32 rx_control)
4441{
4442 u16 tx_seq = __get_reqseq(chan, rx_control);
4443
4444 BT_DBG("chan %p, req_seq %d ctrl 0x%8.8x", chan, tx_seq, rx_control);
4445
4446 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
4447
4448 chan->expected_ack_seq = tx_seq;
4449 l2cap_drop_acked_frames(chan);
4450
4451 if (__is_ctrl_final(chan, rx_control)) {
4452 if (!test_and_clear_bit(CONN_REJ_ACT, &chan->conn_state))
4453 l2cap_retransmit_frames(chan);
4454 } else {
4455 l2cap_retransmit_frames(chan);
4456
4457 if (test_bit(CONN_WAIT_F, &chan->conn_state))
4458 set_bit(CONN_REJ_ACT, &chan->conn_state);
4459 }
4460}
4461static inline void l2cap_data_channel_srejframe(struct l2cap_chan *chan, u32 rx_control)
4462{
4463 u16 tx_seq = __get_reqseq(chan, rx_control);
4464
4465 BT_DBG("chan %p, req_seq %d ctrl 0x%8.8x", chan, tx_seq, rx_control);
4466
4467 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
4468
4469 if (__is_ctrl_poll(chan, rx_control)) {
4470 chan->expected_ack_seq = tx_seq;
4471 l2cap_drop_acked_frames(chan);
4472
4473 set_bit(CONN_SEND_FBIT, &chan->conn_state);
4474 l2cap_retransmit_one_frame(chan, tx_seq);
4475
4476 l2cap_ertm_send(chan);
4477
4478 if (test_bit(CONN_WAIT_F, &chan->conn_state)) {
4479 chan->srej_save_reqseq = tx_seq;
4480 set_bit(CONN_SREJ_ACT, &chan->conn_state);
4481 }
4482 } else if (__is_ctrl_final(chan, rx_control)) {
4483 if (test_bit(CONN_SREJ_ACT, &chan->conn_state) &&
4484 chan->srej_save_reqseq == tx_seq)
4485 clear_bit(CONN_SREJ_ACT, &chan->conn_state);
4486 else
4487 l2cap_retransmit_one_frame(chan, tx_seq);
4488 } else {
4489 l2cap_retransmit_one_frame(chan, tx_seq);
4490 if (test_bit(CONN_WAIT_F, &chan->conn_state)) {
4491 chan->srej_save_reqseq = tx_seq;
4492 set_bit(CONN_SREJ_ACT, &chan->conn_state);
4493 }
4494 }
4495}
4496
4497static inline void l2cap_data_channel_rnrframe(struct l2cap_chan *chan, u32 rx_control)
4498{
4499 u16 tx_seq = __get_reqseq(chan, rx_control);
4500
4501 BT_DBG("chan %p, req_seq %d ctrl 0x%8.8x", chan, tx_seq, rx_control);
4502
4503 set_bit(CONN_REMOTE_BUSY, &chan->conn_state);
4504 chan->expected_ack_seq = tx_seq;
4505 l2cap_drop_acked_frames(chan);
4506
4507 if (__is_ctrl_poll(chan, rx_control))
4508 set_bit(CONN_SEND_FBIT, &chan->conn_state);
4509
4510 if (!test_bit(CONN_SREJ_SENT, &chan->conn_state)) {
4511 __clear_retrans_timer(chan);
4512 if (__is_ctrl_poll(chan, rx_control))
4513 l2cap_send_rr_or_rnr(chan, L2CAP_CTRL_FINAL);
4514 return;
4515 }
4516
4517 if (__is_ctrl_poll(chan, rx_control)) {
4518 l2cap_send_srejtail(chan);
4519 } else {
4520 rx_control = __set_ctrl_super(chan, L2CAP_SUPER_RR);
4521 l2cap_send_sframe(chan, rx_control);
4522 }
4523}
4524
4525static inline int l2cap_data_channel_sframe(struct l2cap_chan *chan, u32 rx_control, struct sk_buff *skb)
4526{
4527 BT_DBG("chan %p rx_control 0x%8.8x len %d", chan, rx_control, skb->len);
4528
4529 if (__is_ctrl_final(chan, rx_control) &&
4530 test_bit(CONN_WAIT_F, &chan->conn_state)) {
4531 __clear_monitor_timer(chan);
4532 if (chan->unacked_frames > 0)
4533 __set_retrans_timer(chan);
4534 clear_bit(CONN_WAIT_F, &chan->conn_state);
4535 }
4536
4537 switch (__get_ctrl_super(chan, rx_control)) {
4538 case L2CAP_SUPER_RR:
4539 l2cap_data_channel_rrframe(chan, rx_control);
4540 break;
4541
4542 case L2CAP_SUPER_REJ:
4543 l2cap_data_channel_rejframe(chan, rx_control);
4544 break;
4545
4546 case L2CAP_SUPER_SREJ:
4547 l2cap_data_channel_srejframe(chan, rx_control);
4548 break;
4549
4550 case L2CAP_SUPER_RNR:
4551 l2cap_data_channel_rnrframe(chan, rx_control);
4552 break;
4553 }
4554
4555 kfree_skb(skb);
4556 return 0;
4557}
4558
4559static int l2cap_ertm_data_rcv(struct l2cap_chan *chan, struct sk_buff *skb)
4560{
4561 u32 control;
4562 u16 req_seq;
4563 int len, next_tx_seq_offset, req_seq_offset;
4564
4565 __unpack_control(chan, skb);
4566
4567 control = __get_control(chan, skb->data);
4568 skb_pull(skb, __ctrl_size(chan));
4569 len = skb->len;
4570
4571 /*
4572 * We can just drop the corrupted I-frame here.
4573 * Receiver will miss it and start proper recovery
4574 * procedures and ask retransmission.
4575 */
4576 if (l2cap_check_fcs(chan, skb))
4577 goto drop;
4578
4579 if (__is_sar_start(chan, control) && !__is_sframe(chan, control))
4580 len -= L2CAP_SDULEN_SIZE;
4581
4582 if (chan->fcs == L2CAP_FCS_CRC16)
4583 len -= L2CAP_FCS_SIZE;
4584
4585 if (len > chan->mps) {
4586 l2cap_send_disconn_req(chan->conn, chan, ECONNRESET);
4587 goto drop;
4588 }
4589
4590 req_seq = __get_reqseq(chan, control);
4591
4592 req_seq_offset = __seq_offset(chan, req_seq, chan->expected_ack_seq);
4593
4594 next_tx_seq_offset = __seq_offset(chan, chan->next_tx_seq,
4595 chan->expected_ack_seq);
4596
4597 /* check for invalid req-seq */
4598 if (req_seq_offset > next_tx_seq_offset) {
4599 l2cap_send_disconn_req(chan->conn, chan, ECONNRESET);
4600 goto drop;
4601 }
4602
4603 if (!__is_sframe(chan, control)) {
4604 if (len < 0) {
4605 l2cap_send_disconn_req(chan->conn, chan, ECONNRESET);
4606 goto drop;
4607 }
4608
4609 l2cap_data_channel_iframe(chan, control, skb);
4610 } else {
4611 if (len != 0) {
4612 BT_ERR("%d", len);
4613 l2cap_send_disconn_req(chan->conn, chan, ECONNRESET);
4614 goto drop;
4615 }
4616
4617 l2cap_data_channel_sframe(chan, control, skb);
4618 }
4619
4620 return 0;
4621
4622drop:
4623 kfree_skb(skb);
4624 return 0;
4625}
4626
4627static inline int l2cap_data_channel(struct l2cap_conn *conn, u16 cid, struct sk_buff *skb)
4628{
4629 struct l2cap_chan *chan;
4630 u32 control;
4631 u16 tx_seq;
4632 int len;
4633
4634 chan = l2cap_get_chan_by_scid(conn, cid);
4635 if (!chan) {
4636 BT_DBG("unknown cid 0x%4.4x", cid);
4637 /* Drop packet and return */
4638 kfree_skb(skb);
4639 return 0;
4640 }
4641
4642 BT_DBG("chan %p, len %d", chan, skb->len);
4643
4644 if (chan->state != BT_CONNECTED)
4645 goto drop;
4646
4647 switch (chan->mode) {
4648 case L2CAP_MODE_BASIC:
4649 /* If socket recv buffers overflows we drop data here
4650 * which is *bad* because L2CAP has to be reliable.
4651 * But we don't have any other choice. L2CAP doesn't
4652 * provide flow control mechanism. */
4653
4654 if (chan->imtu < skb->len)
4655 goto drop;
4656
4657 if (!chan->ops->recv(chan->data, skb))
4658 goto done;
4659 break;
4660
4661 case L2CAP_MODE_ERTM:
4662 l2cap_ertm_data_rcv(chan, skb);
4663
4664 goto done;
4665
4666 case L2CAP_MODE_STREAMING:
4667 control = __get_control(chan, skb->data);
4668 skb_pull(skb, __ctrl_size(chan));
4669 len = skb->len;
4670
4671 if (l2cap_check_fcs(chan, skb))
4672 goto drop;
4673
4674 if (__is_sar_start(chan, control))
4675 len -= L2CAP_SDULEN_SIZE;
4676
4677 if (chan->fcs == L2CAP_FCS_CRC16)
4678 len -= L2CAP_FCS_SIZE;
4679
4680 if (len > chan->mps || len < 0 || __is_sframe(chan, control))
4681 goto drop;
4682
4683 tx_seq = __get_txseq(chan, control);
4684
4685 if (chan->expected_tx_seq != tx_seq) {
4686 /* Frame(s) missing - must discard partial SDU */
4687 kfree_skb(chan->sdu);
4688 chan->sdu = NULL;
4689 chan->sdu_last_frag = NULL;
4690 chan->sdu_len = 0;
4691
4692 /* TODO: Notify userland of missing data */
4693 }
4694
4695 chan->expected_tx_seq = __next_seq(chan, tx_seq);
4696
4697 if (l2cap_reassemble_sdu(chan, skb, control) == -EMSGSIZE)
4698 l2cap_send_disconn_req(chan->conn, chan, ECONNRESET);
4699
4700 goto done;
4701
4702 default:
4703 BT_DBG("chan %p: bad mode 0x%2.2x", chan, chan->mode);
4704 break;
4705 }
4706
4707drop:
4708 kfree_skb(skb);
4709
4710done:
4711 l2cap_chan_unlock(chan);
4712
4713 return 0;
4714}
4715
4716static inline int l2cap_conless_channel(struct l2cap_conn *conn, __le16 psm, struct sk_buff *skb)
4717{
4718 struct l2cap_chan *chan;
4719
4720 chan = l2cap_global_chan_by_psm(0, psm, conn->src, conn->dst);
4721 if (!chan)
4722 goto drop;
4723
4724 BT_DBG("chan %p, len %d", chan, skb->len);
4725
4726 if (chan->state != BT_BOUND && chan->state != BT_CONNECTED)
4727 goto drop;
4728
4729 if (chan->imtu < skb->len)
4730 goto drop;
4731
4732 if (!chan->ops->recv(chan->data, skb))
4733 return 0;
4734
4735drop:
4736 kfree_skb(skb);
4737
4738 return 0;
4739}
4740
4741static inline int l2cap_att_channel(struct l2cap_conn *conn, u16 cid,
4742 struct sk_buff *skb)
4743{
4744 struct l2cap_chan *chan;
4745
4746 chan = l2cap_global_chan_by_scid(0, cid, conn->src, conn->dst);
4747 if (!chan)
4748 goto drop;
4749
4750 BT_DBG("chan %p, len %d", chan, skb->len);
4751
4752 if (chan->state != BT_BOUND && chan->state != BT_CONNECTED)
4753 goto drop;
4754
4755 if (chan->imtu < skb->len)
4756 goto drop;
4757
4758 if (!chan->ops->recv(chan->data, skb))
4759 return 0;
4760
4761drop:
4762 kfree_skb(skb);
4763
4764 return 0;
4765}
4766
4767static void l2cap_recv_frame(struct l2cap_conn *conn, struct sk_buff *skb)
4768{
4769 struct l2cap_hdr *lh = (void *) skb->data;
4770 u16 cid, len;
4771 __le16 psm;
4772
4773 skb_pull(skb, L2CAP_HDR_SIZE);
4774 cid = __le16_to_cpu(lh->cid);
4775 len = __le16_to_cpu(lh->len);
4776
4777 if (len != skb->len) {
4778 kfree_skb(skb);
4779 return;
4780 }
4781
4782 BT_DBG("len %d, cid 0x%4.4x", len, cid);
4783
4784 switch (cid) {
4785 case L2CAP_CID_LE_SIGNALING:
4786 case L2CAP_CID_SIGNALING:
4787 l2cap_sig_channel(conn, skb);
4788 break;
4789
4790 case L2CAP_CID_CONN_LESS:
4791 psm = get_unaligned((__le16 *) skb->data);
4792 skb_pull(skb, 2);
4793 l2cap_conless_channel(conn, psm, skb);
4794 break;
4795
4796 case L2CAP_CID_LE_DATA:
4797 l2cap_att_channel(conn, cid, skb);
4798 break;
4799
4800 case L2CAP_CID_SMP:
4801 if (smp_sig_channel(conn, skb))
4802 l2cap_conn_del(conn->hcon, EACCES);
4803 break;
4804
4805 default:
4806 l2cap_data_channel(conn, cid, skb);
4807 break;
4808 }
4809}
4810
4811/* ---- L2CAP interface with lower layer (HCI) ---- */
4812
4813int l2cap_connect_ind(struct hci_dev *hdev, bdaddr_t *bdaddr)
4814{
4815 int exact = 0, lm1 = 0, lm2 = 0;
4816 struct l2cap_chan *c;
4817
4818 BT_DBG("hdev %s, bdaddr %s", hdev->name, batostr(bdaddr));
4819
4820 /* Find listening sockets and check their link_mode */
4821 read_lock(&chan_list_lock);
4822 list_for_each_entry(c, &chan_list, global_l) {
4823 struct sock *sk = c->sk;
4824
4825 if (c->state != BT_LISTEN)
4826 continue;
4827
4828 if (!bacmp(&bt_sk(sk)->src, &hdev->bdaddr)) {
4829 lm1 |= HCI_LM_ACCEPT;
4830 if (test_bit(FLAG_ROLE_SWITCH, &c->flags))
4831 lm1 |= HCI_LM_MASTER;
4832 exact++;
4833 } else if (!bacmp(&bt_sk(sk)->src, BDADDR_ANY)) {
4834 lm2 |= HCI_LM_ACCEPT;
4835 if (test_bit(FLAG_ROLE_SWITCH, &c->flags))
4836 lm2 |= HCI_LM_MASTER;
4837 }
4838 }
4839 read_unlock(&chan_list_lock);
4840
4841 return exact ? lm1 : lm2;
4842}
4843
4844int l2cap_connect_cfm(struct hci_conn *hcon, u8 status)
4845{
4846 struct l2cap_conn *conn;
4847
4848 BT_DBG("hcon %p bdaddr %s status %d", hcon, batostr(&hcon->dst), status);
4849
4850 if (!status) {
4851 conn = l2cap_conn_add(hcon, status);
4852 if (conn)
4853 l2cap_conn_ready(conn);
4854 } else
4855 l2cap_conn_del(hcon, bt_to_errno(status));
4856
4857 return 0;
4858}
4859
4860int l2cap_disconn_ind(struct hci_conn *hcon)
4861{
4862 struct l2cap_conn *conn = hcon->l2cap_data;
4863
4864 BT_DBG("hcon %p", hcon);
4865
4866 if (!conn)
4867 return HCI_ERROR_REMOTE_USER_TERM;
4868 return conn->disc_reason;
4869}
4870
4871int l2cap_disconn_cfm(struct hci_conn *hcon, u8 reason)
4872{
4873 BT_DBG("hcon %p reason %d", hcon, reason);
4874
4875 l2cap_conn_del(hcon, bt_to_errno(reason));
4876 return 0;
4877}
4878
4879static inline void l2cap_check_encryption(struct l2cap_chan *chan, u8 encrypt)
4880{
4881 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED)
4882 return;
4883
4884 if (encrypt == 0x00) {
4885 if (chan->sec_level == BT_SECURITY_MEDIUM) {
4886 __set_chan_timer(chan, L2CAP_ENC_TIMEOUT);
4887 } else if (chan->sec_level == BT_SECURITY_HIGH)
4888 l2cap_chan_close(chan, ECONNREFUSED);
4889 } else {
4890 if (chan->sec_level == BT_SECURITY_MEDIUM)
4891 __clear_chan_timer(chan);
4892 }
4893}
4894
4895int l2cap_security_cfm(struct hci_conn *hcon, u8 status, u8 encrypt)
4896{
4897 struct l2cap_conn *conn = hcon->l2cap_data;
4898 struct l2cap_chan *chan;
4899
4900 if (!conn)
4901 return 0;
4902
4903 BT_DBG("conn %p", conn);
4904
4905 if (hcon->type == LE_LINK) {
4906 if (!status && encrypt)
4907 smp_distribute_keys(conn, 0);
4908 cancel_delayed_work(&conn->security_timer);
4909 }
4910
4911 mutex_lock(&conn->chan_lock);
4912
4913 list_for_each_entry(chan, &conn->chan_l, list) {
4914 l2cap_chan_lock(chan);
4915
4916 BT_DBG("chan->scid %d", chan->scid);
4917
4918 if (chan->scid == L2CAP_CID_LE_DATA) {
4919 if (!status && encrypt) {
4920 chan->sec_level = hcon->sec_level;
4921 l2cap_chan_ready(chan);
4922 }
4923
4924 l2cap_chan_unlock(chan);
4925 continue;
4926 }
4927
4928 if (test_bit(CONF_CONNECT_PEND, &chan->conf_state)) {
4929 l2cap_chan_unlock(chan);
4930 continue;
4931 }
4932
4933 if (!status && (chan->state == BT_CONNECTED ||
4934 chan->state == BT_CONFIG)) {
4935 struct sock *sk = chan->sk;
4936
4937 clear_bit(BT_SK_SUSPEND, &bt_sk(sk)->flags);
4938 sk->sk_state_change(sk);
4939
4940 l2cap_check_encryption(chan, encrypt);
4941 l2cap_chan_unlock(chan);
4942 continue;
4943 }
4944
4945 if (chan->state == BT_CONNECT) {
4946 if (!status) {
4947 l2cap_send_conn_req(chan);
4948 } else {
4949 __set_chan_timer(chan, L2CAP_DISC_TIMEOUT);
4950 }
4951 } else if (chan->state == BT_CONNECT2) {
4952 struct sock *sk = chan->sk;
4953 struct l2cap_conn_rsp rsp;
4954 __u16 res, stat;
4955
4956 lock_sock(sk);
4957
4958 if (!status) {
4959 if (test_bit(BT_SK_DEFER_SETUP,
4960 &bt_sk(sk)->flags)) {
4961 struct sock *parent = bt_sk(sk)->parent;
4962 res = L2CAP_CR_PEND;
4963 stat = L2CAP_CS_AUTHOR_PEND;
4964 if (parent)
4965 parent->sk_data_ready(parent, 0);
4966 } else {
4967 __l2cap_state_change(chan, BT_CONFIG);
4968 res = L2CAP_CR_SUCCESS;
4969 stat = L2CAP_CS_NO_INFO;
4970 }
4971 } else {
4972 __l2cap_state_change(chan, BT_DISCONN);
4973 __set_chan_timer(chan, L2CAP_DISC_TIMEOUT);
4974 res = L2CAP_CR_SEC_BLOCK;
4975 stat = L2CAP_CS_NO_INFO;
4976 }
4977
4978 release_sock(sk);
4979
4980 rsp.scid = cpu_to_le16(chan->dcid);
4981 rsp.dcid = cpu_to_le16(chan->scid);
4982 rsp.result = cpu_to_le16(res);
4983 rsp.status = cpu_to_le16(stat);
4984 l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_RSP,
4985 sizeof(rsp), &rsp);
4986 }
4987
4988 l2cap_chan_unlock(chan);
4989 }
4990
4991 mutex_unlock(&conn->chan_lock);
4992
4993 return 0;
4994}
4995
4996int l2cap_recv_acldata(struct hci_conn *hcon, struct sk_buff *skb, u16 flags)
4997{
4998 struct l2cap_conn *conn = hcon->l2cap_data;
4999
5000 if (!conn)
5001 conn = l2cap_conn_add(hcon, 0);
5002
5003 if (!conn)
5004 goto drop;
5005
5006 BT_DBG("conn %p len %d flags 0x%x", conn, skb->len, flags);
5007
5008 if (!(flags & ACL_CONT)) {
5009 struct l2cap_hdr *hdr;
5010 int len;
5011
5012 if (conn->rx_len) {
5013 BT_ERR("Unexpected start frame (len %d)", skb->len);
5014 kfree_skb(conn->rx_skb);
5015 conn->rx_skb = NULL;
5016 conn->rx_len = 0;
5017 l2cap_conn_unreliable(conn, ECOMM);
5018 }
5019
5020 /* Start fragment always begin with Basic L2CAP header */
5021 if (skb->len < L2CAP_HDR_SIZE) {
5022 BT_ERR("Frame is too short (len %d)", skb->len);
5023 l2cap_conn_unreliable(conn, ECOMM);
5024 goto drop;
5025 }
5026
5027 hdr = (struct l2cap_hdr *) skb->data;
5028 len = __le16_to_cpu(hdr->len) + L2CAP_HDR_SIZE;
5029
5030 if (len == skb->len) {
5031 /* Complete frame received */
5032 l2cap_recv_frame(conn, skb);
5033 return 0;
5034 }
5035
5036 BT_DBG("Start: total len %d, frag len %d", len, skb->len);
5037
5038 if (skb->len > len) {
5039 BT_ERR("Frame is too long (len %d, expected len %d)",
5040 skb->len, len);
5041 l2cap_conn_unreliable(conn, ECOMM);
5042 goto drop;
5043 }
5044
5045 /* Allocate skb for the complete frame (with header) */
5046 conn->rx_skb = bt_skb_alloc(len, GFP_ATOMIC);
5047 if (!conn->rx_skb)
5048 goto drop;
5049
5050 skb_copy_from_linear_data(skb, skb_put(conn->rx_skb, skb->len),
5051 skb->len);
5052 conn->rx_len = len - skb->len;
5053 } else {
5054 BT_DBG("Cont: frag len %d (expecting %d)", skb->len, conn->rx_len);
5055
5056 if (!conn->rx_len) {
5057 BT_ERR("Unexpected continuation frame (len %d)", skb->len);
5058 l2cap_conn_unreliable(conn, ECOMM);
5059 goto drop;
5060 }
5061
5062 if (skb->len > conn->rx_len) {
5063 BT_ERR("Fragment is too long (len %d, expected %d)",
5064 skb->len, conn->rx_len);
5065 kfree_skb(conn->rx_skb);
5066 conn->rx_skb = NULL;
5067 conn->rx_len = 0;
5068 l2cap_conn_unreliable(conn, ECOMM);
5069 goto drop;
5070 }
5071
5072 skb_copy_from_linear_data(skb, skb_put(conn->rx_skb, skb->len),
5073 skb->len);
5074 conn->rx_len -= skb->len;
5075
5076 if (!conn->rx_len) {
5077 /* Complete frame received */
5078 l2cap_recv_frame(conn, conn->rx_skb);
5079 conn->rx_skb = NULL;
5080 }
5081 }
5082
5083drop:
5084 kfree_skb(skb);
5085 return 0;
5086}
5087
5088static int l2cap_debugfs_show(struct seq_file *f, void *p)
5089{
5090 struct l2cap_chan *c;
5091
5092 read_lock(&chan_list_lock);
5093
5094 list_for_each_entry(c, &chan_list, global_l) {
5095 struct sock *sk = c->sk;
5096
5097 seq_printf(f, "%s %s %d %d 0x%4.4x 0x%4.4x %d %d %d %d\n",
5098 batostr(&bt_sk(sk)->src),
5099 batostr(&bt_sk(sk)->dst),
5100 c->state, __le16_to_cpu(c->psm),
5101 c->scid, c->dcid, c->imtu, c->omtu,
5102 c->sec_level, c->mode);
5103 }
5104
5105 read_unlock(&chan_list_lock);
5106
5107 return 0;
5108}
5109
5110static int l2cap_debugfs_open(struct inode *inode, struct file *file)
5111{
5112 return single_open(file, l2cap_debugfs_show, inode->i_private);
5113}
5114
5115static const struct file_operations l2cap_debugfs_fops = {
5116 .open = l2cap_debugfs_open,
5117 .read = seq_read,
5118 .llseek = seq_lseek,
5119 .release = single_release,
5120};
5121
5122static struct dentry *l2cap_debugfs;
5123
5124int __init l2cap_init(void)
5125{
5126 int err;
5127
5128 err = l2cap_init_sockets();
5129 if (err < 0)
5130 return err;
5131
5132 if (bt_debugfs) {
5133 l2cap_debugfs = debugfs_create_file("l2cap", 0444,
5134 bt_debugfs, NULL, &l2cap_debugfs_fops);
5135 if (!l2cap_debugfs)
5136 BT_ERR("Failed to create L2CAP debug file");
5137 }
5138
5139 return 0;
5140}
5141
5142void l2cap_exit(void)
5143{
5144 debugfs_remove(l2cap_debugfs);
5145 l2cap_cleanup_sockets();
5146}
5147
5148module_param(disable_ertm, bool, 0644);
5149MODULE_PARM_DESC(disable_ertm, "Disable enhanced retransmission mode");