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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/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;
48
49static u32 l2cap_feat_mask = L2CAP_FEAT_FIXED_CHAN | L2CAP_FEAT_UCD;
50
51static LIST_HEAD(chan_list);
52static DEFINE_RWLOCK(chan_list_lock);
53
54static u16 le_max_credits = L2CAP_LE_MAX_CREDITS;
55static u16 le_default_mps = L2CAP_LE_DEFAULT_MPS;
56
57static struct sk_buff *l2cap_build_cmd(struct l2cap_conn *conn,
58 u8 code, u8 ident, u16 dlen, void *data);
59static void l2cap_send_cmd(struct l2cap_conn *conn, u8 ident, u8 code, u16 len,
60 void *data);
61static int l2cap_build_conf_req(struct l2cap_chan *chan, void *data);
62static void l2cap_send_disconn_req(struct l2cap_chan *chan, int err);
63
64static void l2cap_tx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
65 struct sk_buff_head *skbs, u8 event);
66
67static inline u8 bdaddr_type(u8 link_type, u8 bdaddr_type)
68{
69 if (link_type == LE_LINK) {
70 if (bdaddr_type == ADDR_LE_DEV_PUBLIC)
71 return BDADDR_LE_PUBLIC;
72 else
73 return BDADDR_LE_RANDOM;
74 }
75
76 return BDADDR_BREDR;
77}
78
79static inline u8 bdaddr_src_type(struct hci_conn *hcon)
80{
81 return bdaddr_type(hcon->type, hcon->src_type);
82}
83
84static inline u8 bdaddr_dst_type(struct hci_conn *hcon)
85{
86 return bdaddr_type(hcon->type, hcon->dst_type);
87}
88
89/* ---- L2CAP channels ---- */
90
91static struct l2cap_chan *__l2cap_get_chan_by_dcid(struct l2cap_conn *conn,
92 u16 cid)
93{
94 struct l2cap_chan *c;
95
96 list_for_each_entry(c, &conn->chan_l, list) {
97 if (c->dcid == cid)
98 return c;
99 }
100 return NULL;
101}
102
103static struct l2cap_chan *__l2cap_get_chan_by_scid(struct l2cap_conn *conn,
104 u16 cid)
105{
106 struct l2cap_chan *c;
107
108 list_for_each_entry(c, &conn->chan_l, list) {
109 if (c->scid == cid)
110 return c;
111 }
112 return NULL;
113}
114
115/* Find channel with given SCID.
116 * Returns locked channel. */
117static struct l2cap_chan *l2cap_get_chan_by_scid(struct l2cap_conn *conn,
118 u16 cid)
119{
120 struct l2cap_chan *c;
121
122 mutex_lock(&conn->chan_lock);
123 c = __l2cap_get_chan_by_scid(conn, cid);
124 if (c)
125 l2cap_chan_lock(c);
126 mutex_unlock(&conn->chan_lock);
127
128 return c;
129}
130
131/* Find channel with given DCID.
132 * Returns locked channel.
133 */
134static struct l2cap_chan *l2cap_get_chan_by_dcid(struct l2cap_conn *conn,
135 u16 cid)
136{
137 struct l2cap_chan *c;
138
139 mutex_lock(&conn->chan_lock);
140 c = __l2cap_get_chan_by_dcid(conn, cid);
141 if (c)
142 l2cap_chan_lock(c);
143 mutex_unlock(&conn->chan_lock);
144
145 return c;
146}
147
148static struct l2cap_chan *__l2cap_get_chan_by_ident(struct l2cap_conn *conn,
149 u8 ident)
150{
151 struct l2cap_chan *c;
152
153 list_for_each_entry(c, &conn->chan_l, list) {
154 if (c->ident == ident)
155 return c;
156 }
157 return NULL;
158}
159
160static struct l2cap_chan *l2cap_get_chan_by_ident(struct l2cap_conn *conn,
161 u8 ident)
162{
163 struct l2cap_chan *c;
164
165 mutex_lock(&conn->chan_lock);
166 c = __l2cap_get_chan_by_ident(conn, ident);
167 if (c)
168 l2cap_chan_lock(c);
169 mutex_unlock(&conn->chan_lock);
170
171 return c;
172}
173
174static struct l2cap_chan *__l2cap_global_chan_by_addr(__le16 psm, bdaddr_t *src)
175{
176 struct l2cap_chan *c;
177
178 list_for_each_entry(c, &chan_list, global_l) {
179 if (c->sport == psm && !bacmp(&c->src, src))
180 return c;
181 }
182 return NULL;
183}
184
185int l2cap_add_psm(struct l2cap_chan *chan, bdaddr_t *src, __le16 psm)
186{
187 int err;
188
189 write_lock(&chan_list_lock);
190
191 if (psm && __l2cap_global_chan_by_addr(psm, src)) {
192 err = -EADDRINUSE;
193 goto done;
194 }
195
196 if (psm) {
197 chan->psm = psm;
198 chan->sport = psm;
199 err = 0;
200 } else {
201 u16 p, start, end, incr;
202
203 if (chan->src_type == BDADDR_BREDR) {
204 start = L2CAP_PSM_DYN_START;
205 end = L2CAP_PSM_AUTO_END;
206 incr = 2;
207 } else {
208 start = L2CAP_PSM_LE_DYN_START;
209 end = L2CAP_PSM_LE_DYN_END;
210 incr = 1;
211 }
212
213 err = -EINVAL;
214 for (p = start; p <= end; p += incr)
215 if (!__l2cap_global_chan_by_addr(cpu_to_le16(p), src)) {
216 chan->psm = cpu_to_le16(p);
217 chan->sport = cpu_to_le16(p);
218 err = 0;
219 break;
220 }
221 }
222
223done:
224 write_unlock(&chan_list_lock);
225 return err;
226}
227EXPORT_SYMBOL_GPL(l2cap_add_psm);
228
229int l2cap_add_scid(struct l2cap_chan *chan, __u16 scid)
230{
231 write_lock(&chan_list_lock);
232
233 /* Override the defaults (which are for conn-oriented) */
234 chan->omtu = L2CAP_DEFAULT_MTU;
235 chan->chan_type = L2CAP_CHAN_FIXED;
236
237 chan->scid = scid;
238
239 write_unlock(&chan_list_lock);
240
241 return 0;
242}
243
244static u16 l2cap_alloc_cid(struct l2cap_conn *conn)
245{
246 u16 cid, dyn_end;
247
248 if (conn->hcon->type == LE_LINK)
249 dyn_end = L2CAP_CID_LE_DYN_END;
250 else
251 dyn_end = L2CAP_CID_DYN_END;
252
253 for (cid = L2CAP_CID_DYN_START; cid <= dyn_end; cid++) {
254 if (!__l2cap_get_chan_by_scid(conn, cid))
255 return cid;
256 }
257
258 return 0;
259}
260
261static void l2cap_state_change(struct l2cap_chan *chan, int state)
262{
263 BT_DBG("chan %p %s -> %s", chan, state_to_string(chan->state),
264 state_to_string(state));
265
266 chan->state = state;
267 chan->ops->state_change(chan, state, 0);
268}
269
270static inline void l2cap_state_change_and_error(struct l2cap_chan *chan,
271 int state, int err)
272{
273 chan->state = state;
274 chan->ops->state_change(chan, chan->state, err);
275}
276
277static inline void l2cap_chan_set_err(struct l2cap_chan *chan, int err)
278{
279 chan->ops->state_change(chan, chan->state, err);
280}
281
282static void __set_retrans_timer(struct l2cap_chan *chan)
283{
284 if (!delayed_work_pending(&chan->monitor_timer) &&
285 chan->retrans_timeout) {
286 l2cap_set_timer(chan, &chan->retrans_timer,
287 msecs_to_jiffies(chan->retrans_timeout));
288 }
289}
290
291static void __set_monitor_timer(struct l2cap_chan *chan)
292{
293 __clear_retrans_timer(chan);
294 if (chan->monitor_timeout) {
295 l2cap_set_timer(chan, &chan->monitor_timer,
296 msecs_to_jiffies(chan->monitor_timeout));
297 }
298}
299
300static struct sk_buff *l2cap_ertm_seq_in_queue(struct sk_buff_head *head,
301 u16 seq)
302{
303 struct sk_buff *skb;
304
305 skb_queue_walk(head, skb) {
306 if (bt_cb(skb)->l2cap.txseq == seq)
307 return skb;
308 }
309
310 return NULL;
311}
312
313/* ---- L2CAP sequence number lists ---- */
314
315/* For ERTM, ordered lists of sequence numbers must be tracked for
316 * SREJ requests that are received and for frames that are to be
317 * retransmitted. These seq_list functions implement a singly-linked
318 * list in an array, where membership in the list can also be checked
319 * in constant time. Items can also be added to the tail of the list
320 * and removed from the head in constant time, without further memory
321 * allocs or frees.
322 */
323
324static int l2cap_seq_list_init(struct l2cap_seq_list *seq_list, u16 size)
325{
326 size_t alloc_size, i;
327
328 /* Allocated size is a power of 2 to map sequence numbers
329 * (which may be up to 14 bits) in to a smaller array that is
330 * sized for the negotiated ERTM transmit windows.
331 */
332 alloc_size = roundup_pow_of_two(size);
333
334 seq_list->list = kmalloc(sizeof(u16) * alloc_size, GFP_KERNEL);
335 if (!seq_list->list)
336 return -ENOMEM;
337
338 seq_list->mask = alloc_size - 1;
339 seq_list->head = L2CAP_SEQ_LIST_CLEAR;
340 seq_list->tail = L2CAP_SEQ_LIST_CLEAR;
341 for (i = 0; i < alloc_size; i++)
342 seq_list->list[i] = L2CAP_SEQ_LIST_CLEAR;
343
344 return 0;
345}
346
347static inline void l2cap_seq_list_free(struct l2cap_seq_list *seq_list)
348{
349 kfree(seq_list->list);
350}
351
352static inline bool l2cap_seq_list_contains(struct l2cap_seq_list *seq_list,
353 u16 seq)
354{
355 /* Constant-time check for list membership */
356 return seq_list->list[seq & seq_list->mask] != L2CAP_SEQ_LIST_CLEAR;
357}
358
359static inline u16 l2cap_seq_list_pop(struct l2cap_seq_list *seq_list)
360{
361 u16 seq = seq_list->head;
362 u16 mask = seq_list->mask;
363
364 seq_list->head = seq_list->list[seq & mask];
365 seq_list->list[seq & mask] = L2CAP_SEQ_LIST_CLEAR;
366
367 if (seq_list->head == L2CAP_SEQ_LIST_TAIL) {
368 seq_list->head = L2CAP_SEQ_LIST_CLEAR;
369 seq_list->tail = L2CAP_SEQ_LIST_CLEAR;
370 }
371
372 return seq;
373}
374
375static void l2cap_seq_list_clear(struct l2cap_seq_list *seq_list)
376{
377 u16 i;
378
379 if (seq_list->head == L2CAP_SEQ_LIST_CLEAR)
380 return;
381
382 for (i = 0; i <= seq_list->mask; i++)
383 seq_list->list[i] = L2CAP_SEQ_LIST_CLEAR;
384
385 seq_list->head = L2CAP_SEQ_LIST_CLEAR;
386 seq_list->tail = L2CAP_SEQ_LIST_CLEAR;
387}
388
389static void l2cap_seq_list_append(struct l2cap_seq_list *seq_list, u16 seq)
390{
391 u16 mask = seq_list->mask;
392
393 /* All appends happen in constant time */
394
395 if (seq_list->list[seq & mask] != L2CAP_SEQ_LIST_CLEAR)
396 return;
397
398 if (seq_list->tail == L2CAP_SEQ_LIST_CLEAR)
399 seq_list->head = seq;
400 else
401 seq_list->list[seq_list->tail & mask] = seq;
402
403 seq_list->tail = seq;
404 seq_list->list[seq & mask] = L2CAP_SEQ_LIST_TAIL;
405}
406
407static void l2cap_chan_timeout(struct work_struct *work)
408{
409 struct l2cap_chan *chan = container_of(work, struct l2cap_chan,
410 chan_timer.work);
411 struct l2cap_conn *conn = chan->conn;
412 int reason;
413
414 BT_DBG("chan %p state %s", chan, state_to_string(chan->state));
415
416 mutex_lock(&conn->chan_lock);
417 l2cap_chan_lock(chan);
418
419 if (chan->state == BT_CONNECTED || chan->state == BT_CONFIG)
420 reason = ECONNREFUSED;
421 else if (chan->state == BT_CONNECT &&
422 chan->sec_level != BT_SECURITY_SDP)
423 reason = ECONNREFUSED;
424 else
425 reason = ETIMEDOUT;
426
427 l2cap_chan_close(chan, reason);
428
429 l2cap_chan_unlock(chan);
430
431 chan->ops->close(chan);
432 mutex_unlock(&conn->chan_lock);
433
434 l2cap_chan_put(chan);
435}
436
437struct l2cap_chan *l2cap_chan_create(void)
438{
439 struct l2cap_chan *chan;
440
441 chan = kzalloc(sizeof(*chan), GFP_ATOMIC);
442 if (!chan)
443 return NULL;
444
445 mutex_init(&chan->lock);
446
447 /* Set default lock nesting level */
448 atomic_set(&chan->nesting, L2CAP_NESTING_NORMAL);
449
450 write_lock(&chan_list_lock);
451 list_add(&chan->global_l, &chan_list);
452 write_unlock(&chan_list_lock);
453
454 INIT_DELAYED_WORK(&chan->chan_timer, l2cap_chan_timeout);
455
456 chan->state = BT_OPEN;
457
458 kref_init(&chan->kref);
459
460 /* This flag is cleared in l2cap_chan_ready() */
461 set_bit(CONF_NOT_COMPLETE, &chan->conf_state);
462
463 BT_DBG("chan %p", chan);
464
465 return chan;
466}
467EXPORT_SYMBOL_GPL(l2cap_chan_create);
468
469static void l2cap_chan_destroy(struct kref *kref)
470{
471 struct l2cap_chan *chan = container_of(kref, struct l2cap_chan, kref);
472
473 BT_DBG("chan %p", chan);
474
475 write_lock(&chan_list_lock);
476 list_del(&chan->global_l);
477 write_unlock(&chan_list_lock);
478
479 kfree(chan);
480}
481
482void l2cap_chan_hold(struct l2cap_chan *c)
483{
484 BT_DBG("chan %p orig refcnt %d", c, atomic_read(&c->kref.refcount));
485
486 kref_get(&c->kref);
487}
488
489void l2cap_chan_put(struct l2cap_chan *c)
490{
491 BT_DBG("chan %p orig refcnt %d", c, atomic_read(&c->kref.refcount));
492
493 kref_put(&c->kref, l2cap_chan_destroy);
494}
495EXPORT_SYMBOL_GPL(l2cap_chan_put);
496
497void l2cap_chan_set_defaults(struct l2cap_chan *chan)
498{
499 chan->fcs = L2CAP_FCS_CRC16;
500 chan->max_tx = L2CAP_DEFAULT_MAX_TX;
501 chan->tx_win = L2CAP_DEFAULT_TX_WINDOW;
502 chan->tx_win_max = L2CAP_DEFAULT_TX_WINDOW;
503 chan->remote_max_tx = chan->max_tx;
504 chan->remote_tx_win = chan->tx_win;
505 chan->ack_win = L2CAP_DEFAULT_TX_WINDOW;
506 chan->sec_level = BT_SECURITY_LOW;
507 chan->flush_to = L2CAP_DEFAULT_FLUSH_TO;
508 chan->retrans_timeout = L2CAP_DEFAULT_RETRANS_TO;
509 chan->monitor_timeout = L2CAP_DEFAULT_MONITOR_TO;
510 chan->conf_state = 0;
511
512 set_bit(FLAG_FORCE_ACTIVE, &chan->flags);
513}
514EXPORT_SYMBOL_GPL(l2cap_chan_set_defaults);
515
516static void l2cap_le_flowctl_init(struct l2cap_chan *chan)
517{
518 chan->sdu = NULL;
519 chan->sdu_last_frag = NULL;
520 chan->sdu_len = 0;
521 chan->tx_credits = 0;
522 chan->rx_credits = le_max_credits;
523 chan->mps = min_t(u16, chan->imtu, le_default_mps);
524
525 skb_queue_head_init(&chan->tx_q);
526}
527
528void __l2cap_chan_add(struct l2cap_conn *conn, struct l2cap_chan *chan)
529{
530 BT_DBG("conn %p, psm 0x%2.2x, dcid 0x%4.4x", conn,
531 __le16_to_cpu(chan->psm), chan->dcid);
532
533 conn->disc_reason = HCI_ERROR_REMOTE_USER_TERM;
534
535 chan->conn = conn;
536
537 switch (chan->chan_type) {
538 case L2CAP_CHAN_CONN_ORIENTED:
539 /* Alloc CID for connection-oriented socket */
540 chan->scid = l2cap_alloc_cid(conn);
541 if (conn->hcon->type == ACL_LINK)
542 chan->omtu = L2CAP_DEFAULT_MTU;
543 break;
544
545 case L2CAP_CHAN_CONN_LESS:
546 /* Connectionless socket */
547 chan->scid = L2CAP_CID_CONN_LESS;
548 chan->dcid = L2CAP_CID_CONN_LESS;
549 chan->omtu = L2CAP_DEFAULT_MTU;
550 break;
551
552 case L2CAP_CHAN_FIXED:
553 /* Caller will set CID and CID specific MTU values */
554 break;
555
556 default:
557 /* Raw socket can send/recv signalling messages only */
558 chan->scid = L2CAP_CID_SIGNALING;
559 chan->dcid = L2CAP_CID_SIGNALING;
560 chan->omtu = L2CAP_DEFAULT_MTU;
561 }
562
563 chan->local_id = L2CAP_BESTEFFORT_ID;
564 chan->local_stype = L2CAP_SERV_BESTEFFORT;
565 chan->local_msdu = L2CAP_DEFAULT_MAX_SDU_SIZE;
566 chan->local_sdu_itime = L2CAP_DEFAULT_SDU_ITIME;
567 chan->local_acc_lat = L2CAP_DEFAULT_ACC_LAT;
568 chan->local_flush_to = L2CAP_EFS_DEFAULT_FLUSH_TO;
569
570 l2cap_chan_hold(chan);
571
572 /* Only keep a reference for fixed channels if they requested it */
573 if (chan->chan_type != L2CAP_CHAN_FIXED ||
574 test_bit(FLAG_HOLD_HCI_CONN, &chan->flags))
575 hci_conn_hold(conn->hcon);
576
577 list_add(&chan->list, &conn->chan_l);
578}
579
580void l2cap_chan_add(struct l2cap_conn *conn, struct l2cap_chan *chan)
581{
582 mutex_lock(&conn->chan_lock);
583 __l2cap_chan_add(conn, chan);
584 mutex_unlock(&conn->chan_lock);
585}
586
587void l2cap_chan_del(struct l2cap_chan *chan, int err)
588{
589 struct l2cap_conn *conn = chan->conn;
590
591 __clear_chan_timer(chan);
592
593 BT_DBG("chan %p, conn %p, err %d, state %s", chan, conn, err,
594 state_to_string(chan->state));
595
596 chan->ops->teardown(chan, err);
597
598 if (conn) {
599 struct amp_mgr *mgr = conn->hcon->amp_mgr;
600 /* Delete from channel list */
601 list_del(&chan->list);
602
603 l2cap_chan_put(chan);
604
605 chan->conn = NULL;
606
607 /* Reference was only held for non-fixed channels or
608 * fixed channels that explicitly requested it using the
609 * FLAG_HOLD_HCI_CONN flag.
610 */
611 if (chan->chan_type != L2CAP_CHAN_FIXED ||
612 test_bit(FLAG_HOLD_HCI_CONN, &chan->flags))
613 hci_conn_drop(conn->hcon);
614
615 if (mgr && mgr->bredr_chan == chan)
616 mgr->bredr_chan = NULL;
617 }
618
619 if (chan->hs_hchan) {
620 struct hci_chan *hs_hchan = chan->hs_hchan;
621
622 BT_DBG("chan %p disconnect hs_hchan %p", chan, hs_hchan);
623 amp_disconnect_logical_link(hs_hchan);
624 }
625
626 if (test_bit(CONF_NOT_COMPLETE, &chan->conf_state))
627 return;
628
629 switch(chan->mode) {
630 case L2CAP_MODE_BASIC:
631 break;
632
633 case L2CAP_MODE_LE_FLOWCTL:
634 skb_queue_purge(&chan->tx_q);
635 break;
636
637 case L2CAP_MODE_ERTM:
638 __clear_retrans_timer(chan);
639 __clear_monitor_timer(chan);
640 __clear_ack_timer(chan);
641
642 skb_queue_purge(&chan->srej_q);
643
644 l2cap_seq_list_free(&chan->srej_list);
645 l2cap_seq_list_free(&chan->retrans_list);
646
647 /* fall through */
648
649 case L2CAP_MODE_STREAMING:
650 skb_queue_purge(&chan->tx_q);
651 break;
652 }
653
654 return;
655}
656EXPORT_SYMBOL_GPL(l2cap_chan_del);
657
658static void l2cap_conn_update_id_addr(struct work_struct *work)
659{
660 struct l2cap_conn *conn = container_of(work, struct l2cap_conn,
661 id_addr_update_work);
662 struct hci_conn *hcon = conn->hcon;
663 struct l2cap_chan *chan;
664
665 mutex_lock(&conn->chan_lock);
666
667 list_for_each_entry(chan, &conn->chan_l, list) {
668 l2cap_chan_lock(chan);
669 bacpy(&chan->dst, &hcon->dst);
670 chan->dst_type = bdaddr_dst_type(hcon);
671 l2cap_chan_unlock(chan);
672 }
673
674 mutex_unlock(&conn->chan_lock);
675}
676
677static void l2cap_chan_le_connect_reject(struct l2cap_chan *chan)
678{
679 struct l2cap_conn *conn = chan->conn;
680 struct l2cap_le_conn_rsp rsp;
681 u16 result;
682
683 if (test_bit(FLAG_DEFER_SETUP, &chan->flags))
684 result = L2CAP_CR_AUTHORIZATION;
685 else
686 result = L2CAP_CR_BAD_PSM;
687
688 l2cap_state_change(chan, BT_DISCONN);
689
690 rsp.dcid = cpu_to_le16(chan->scid);
691 rsp.mtu = cpu_to_le16(chan->imtu);
692 rsp.mps = cpu_to_le16(chan->mps);
693 rsp.credits = cpu_to_le16(chan->rx_credits);
694 rsp.result = cpu_to_le16(result);
695
696 l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CONN_RSP, sizeof(rsp),
697 &rsp);
698}
699
700static void l2cap_chan_connect_reject(struct l2cap_chan *chan)
701{
702 struct l2cap_conn *conn = chan->conn;
703 struct l2cap_conn_rsp rsp;
704 u16 result;
705
706 if (test_bit(FLAG_DEFER_SETUP, &chan->flags))
707 result = L2CAP_CR_SEC_BLOCK;
708 else
709 result = L2CAP_CR_BAD_PSM;
710
711 l2cap_state_change(chan, BT_DISCONN);
712
713 rsp.scid = cpu_to_le16(chan->dcid);
714 rsp.dcid = cpu_to_le16(chan->scid);
715 rsp.result = cpu_to_le16(result);
716 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
717
718 l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_RSP, sizeof(rsp), &rsp);
719}
720
721void l2cap_chan_close(struct l2cap_chan *chan, int reason)
722{
723 struct l2cap_conn *conn = chan->conn;
724
725 BT_DBG("chan %p state %s", chan, state_to_string(chan->state));
726
727 switch (chan->state) {
728 case BT_LISTEN:
729 chan->ops->teardown(chan, 0);
730 break;
731
732 case BT_CONNECTED:
733 case BT_CONFIG:
734 if (chan->chan_type == L2CAP_CHAN_CONN_ORIENTED) {
735 __set_chan_timer(chan, chan->ops->get_sndtimeo(chan));
736 l2cap_send_disconn_req(chan, reason);
737 } else
738 l2cap_chan_del(chan, reason);
739 break;
740
741 case BT_CONNECT2:
742 if (chan->chan_type == L2CAP_CHAN_CONN_ORIENTED) {
743 if (conn->hcon->type == ACL_LINK)
744 l2cap_chan_connect_reject(chan);
745 else if (conn->hcon->type == LE_LINK)
746 l2cap_chan_le_connect_reject(chan);
747 }
748
749 l2cap_chan_del(chan, reason);
750 break;
751
752 case BT_CONNECT:
753 case BT_DISCONN:
754 l2cap_chan_del(chan, reason);
755 break;
756
757 default:
758 chan->ops->teardown(chan, 0);
759 break;
760 }
761}
762EXPORT_SYMBOL(l2cap_chan_close);
763
764static inline u8 l2cap_get_auth_type(struct l2cap_chan *chan)
765{
766 switch (chan->chan_type) {
767 case L2CAP_CHAN_RAW:
768 switch (chan->sec_level) {
769 case BT_SECURITY_HIGH:
770 case BT_SECURITY_FIPS:
771 return HCI_AT_DEDICATED_BONDING_MITM;
772 case BT_SECURITY_MEDIUM:
773 return HCI_AT_DEDICATED_BONDING;
774 default:
775 return HCI_AT_NO_BONDING;
776 }
777 break;
778 case L2CAP_CHAN_CONN_LESS:
779 if (chan->psm == cpu_to_le16(L2CAP_PSM_3DSP)) {
780 if (chan->sec_level == BT_SECURITY_LOW)
781 chan->sec_level = BT_SECURITY_SDP;
782 }
783 if (chan->sec_level == BT_SECURITY_HIGH ||
784 chan->sec_level == BT_SECURITY_FIPS)
785 return HCI_AT_NO_BONDING_MITM;
786 else
787 return HCI_AT_NO_BONDING;
788 break;
789 case L2CAP_CHAN_CONN_ORIENTED:
790 if (chan->psm == cpu_to_le16(L2CAP_PSM_SDP)) {
791 if (chan->sec_level == BT_SECURITY_LOW)
792 chan->sec_level = BT_SECURITY_SDP;
793
794 if (chan->sec_level == BT_SECURITY_HIGH ||
795 chan->sec_level == BT_SECURITY_FIPS)
796 return HCI_AT_NO_BONDING_MITM;
797 else
798 return HCI_AT_NO_BONDING;
799 }
800 /* fall through */
801 default:
802 switch (chan->sec_level) {
803 case BT_SECURITY_HIGH:
804 case BT_SECURITY_FIPS:
805 return HCI_AT_GENERAL_BONDING_MITM;
806 case BT_SECURITY_MEDIUM:
807 return HCI_AT_GENERAL_BONDING;
808 default:
809 return HCI_AT_NO_BONDING;
810 }
811 break;
812 }
813}
814
815/* Service level security */
816int l2cap_chan_check_security(struct l2cap_chan *chan, bool initiator)
817{
818 struct l2cap_conn *conn = chan->conn;
819 __u8 auth_type;
820
821 if (conn->hcon->type == LE_LINK)
822 return smp_conn_security(conn->hcon, chan->sec_level);
823
824 auth_type = l2cap_get_auth_type(chan);
825
826 return hci_conn_security(conn->hcon, chan->sec_level, auth_type,
827 initiator);
828}
829
830static u8 l2cap_get_ident(struct l2cap_conn *conn)
831{
832 u8 id;
833
834 /* Get next available identificator.
835 * 1 - 128 are used by kernel.
836 * 129 - 199 are reserved.
837 * 200 - 254 are used by utilities like l2ping, etc.
838 */
839
840 mutex_lock(&conn->ident_lock);
841
842 if (++conn->tx_ident > 128)
843 conn->tx_ident = 1;
844
845 id = conn->tx_ident;
846
847 mutex_unlock(&conn->ident_lock);
848
849 return id;
850}
851
852static void l2cap_send_cmd(struct l2cap_conn *conn, u8 ident, u8 code, u16 len,
853 void *data)
854{
855 struct sk_buff *skb = l2cap_build_cmd(conn, code, ident, len, data);
856 u8 flags;
857
858 BT_DBG("code 0x%2.2x", code);
859
860 if (!skb)
861 return;
862
863 /* Use NO_FLUSH if supported or we have an LE link (which does
864 * not support auto-flushing packets) */
865 if (lmp_no_flush_capable(conn->hcon->hdev) ||
866 conn->hcon->type == LE_LINK)
867 flags = ACL_START_NO_FLUSH;
868 else
869 flags = ACL_START;
870
871 bt_cb(skb)->force_active = BT_POWER_FORCE_ACTIVE_ON;
872 skb->priority = HCI_PRIO_MAX;
873
874 hci_send_acl(conn->hchan, skb, flags);
875}
876
877static bool __chan_is_moving(struct l2cap_chan *chan)
878{
879 return chan->move_state != L2CAP_MOVE_STABLE &&
880 chan->move_state != L2CAP_MOVE_WAIT_PREPARE;
881}
882
883static void l2cap_do_send(struct l2cap_chan *chan, struct sk_buff *skb)
884{
885 struct hci_conn *hcon = chan->conn->hcon;
886 u16 flags;
887
888 BT_DBG("chan %p, skb %p len %d priority %u", chan, skb, skb->len,
889 skb->priority);
890
891 if (chan->hs_hcon && !__chan_is_moving(chan)) {
892 if (chan->hs_hchan)
893 hci_send_acl(chan->hs_hchan, skb, ACL_COMPLETE);
894 else
895 kfree_skb(skb);
896
897 return;
898 }
899
900 /* Use NO_FLUSH for LE links (where this is the only option) or
901 * if the BR/EDR link supports it and flushing has not been
902 * explicitly requested (through FLAG_FLUSHABLE).
903 */
904 if (hcon->type == LE_LINK ||
905 (!test_bit(FLAG_FLUSHABLE, &chan->flags) &&
906 lmp_no_flush_capable(hcon->hdev)))
907 flags = ACL_START_NO_FLUSH;
908 else
909 flags = ACL_START;
910
911 bt_cb(skb)->force_active = test_bit(FLAG_FORCE_ACTIVE, &chan->flags);
912 hci_send_acl(chan->conn->hchan, skb, flags);
913}
914
915static void __unpack_enhanced_control(u16 enh, struct l2cap_ctrl *control)
916{
917 control->reqseq = (enh & L2CAP_CTRL_REQSEQ) >> L2CAP_CTRL_REQSEQ_SHIFT;
918 control->final = (enh & L2CAP_CTRL_FINAL) >> L2CAP_CTRL_FINAL_SHIFT;
919
920 if (enh & L2CAP_CTRL_FRAME_TYPE) {
921 /* S-Frame */
922 control->sframe = 1;
923 control->poll = (enh & L2CAP_CTRL_POLL) >> L2CAP_CTRL_POLL_SHIFT;
924 control->super = (enh & L2CAP_CTRL_SUPERVISE) >> L2CAP_CTRL_SUPER_SHIFT;
925
926 control->sar = 0;
927 control->txseq = 0;
928 } else {
929 /* I-Frame */
930 control->sframe = 0;
931 control->sar = (enh & L2CAP_CTRL_SAR) >> L2CAP_CTRL_SAR_SHIFT;
932 control->txseq = (enh & L2CAP_CTRL_TXSEQ) >> L2CAP_CTRL_TXSEQ_SHIFT;
933
934 control->poll = 0;
935 control->super = 0;
936 }
937}
938
939static void __unpack_extended_control(u32 ext, struct l2cap_ctrl *control)
940{
941 control->reqseq = (ext & L2CAP_EXT_CTRL_REQSEQ) >> L2CAP_EXT_CTRL_REQSEQ_SHIFT;
942 control->final = (ext & L2CAP_EXT_CTRL_FINAL) >> L2CAP_EXT_CTRL_FINAL_SHIFT;
943
944 if (ext & L2CAP_EXT_CTRL_FRAME_TYPE) {
945 /* S-Frame */
946 control->sframe = 1;
947 control->poll = (ext & L2CAP_EXT_CTRL_POLL) >> L2CAP_EXT_CTRL_POLL_SHIFT;
948 control->super = (ext & L2CAP_EXT_CTRL_SUPERVISE) >> L2CAP_EXT_CTRL_SUPER_SHIFT;
949
950 control->sar = 0;
951 control->txseq = 0;
952 } else {
953 /* I-Frame */
954 control->sframe = 0;
955 control->sar = (ext & L2CAP_EXT_CTRL_SAR) >> L2CAP_EXT_CTRL_SAR_SHIFT;
956 control->txseq = (ext & L2CAP_EXT_CTRL_TXSEQ) >> L2CAP_EXT_CTRL_TXSEQ_SHIFT;
957
958 control->poll = 0;
959 control->super = 0;
960 }
961}
962
963static inline void __unpack_control(struct l2cap_chan *chan,
964 struct sk_buff *skb)
965{
966 if (test_bit(FLAG_EXT_CTRL, &chan->flags)) {
967 __unpack_extended_control(get_unaligned_le32(skb->data),
968 &bt_cb(skb)->l2cap);
969 skb_pull(skb, L2CAP_EXT_CTRL_SIZE);
970 } else {
971 __unpack_enhanced_control(get_unaligned_le16(skb->data),
972 &bt_cb(skb)->l2cap);
973 skb_pull(skb, L2CAP_ENH_CTRL_SIZE);
974 }
975}
976
977static u32 __pack_extended_control(struct l2cap_ctrl *control)
978{
979 u32 packed;
980
981 packed = control->reqseq << L2CAP_EXT_CTRL_REQSEQ_SHIFT;
982 packed |= control->final << L2CAP_EXT_CTRL_FINAL_SHIFT;
983
984 if (control->sframe) {
985 packed |= control->poll << L2CAP_EXT_CTRL_POLL_SHIFT;
986 packed |= control->super << L2CAP_EXT_CTRL_SUPER_SHIFT;
987 packed |= L2CAP_EXT_CTRL_FRAME_TYPE;
988 } else {
989 packed |= control->sar << L2CAP_EXT_CTRL_SAR_SHIFT;
990 packed |= control->txseq << L2CAP_EXT_CTRL_TXSEQ_SHIFT;
991 }
992
993 return packed;
994}
995
996static u16 __pack_enhanced_control(struct l2cap_ctrl *control)
997{
998 u16 packed;
999
1000 packed = control->reqseq << L2CAP_CTRL_REQSEQ_SHIFT;
1001 packed |= control->final << L2CAP_CTRL_FINAL_SHIFT;
1002
1003 if (control->sframe) {
1004 packed |= control->poll << L2CAP_CTRL_POLL_SHIFT;
1005 packed |= control->super << L2CAP_CTRL_SUPER_SHIFT;
1006 packed |= L2CAP_CTRL_FRAME_TYPE;
1007 } else {
1008 packed |= control->sar << L2CAP_CTRL_SAR_SHIFT;
1009 packed |= control->txseq << L2CAP_CTRL_TXSEQ_SHIFT;
1010 }
1011
1012 return packed;
1013}
1014
1015static inline void __pack_control(struct l2cap_chan *chan,
1016 struct l2cap_ctrl *control,
1017 struct sk_buff *skb)
1018{
1019 if (test_bit(FLAG_EXT_CTRL, &chan->flags)) {
1020 put_unaligned_le32(__pack_extended_control(control),
1021 skb->data + L2CAP_HDR_SIZE);
1022 } else {
1023 put_unaligned_le16(__pack_enhanced_control(control),
1024 skb->data + L2CAP_HDR_SIZE);
1025 }
1026}
1027
1028static inline unsigned int __ertm_hdr_size(struct l2cap_chan *chan)
1029{
1030 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
1031 return L2CAP_EXT_HDR_SIZE;
1032 else
1033 return L2CAP_ENH_HDR_SIZE;
1034}
1035
1036static struct sk_buff *l2cap_create_sframe_pdu(struct l2cap_chan *chan,
1037 u32 control)
1038{
1039 struct sk_buff *skb;
1040 struct l2cap_hdr *lh;
1041 int hlen = __ertm_hdr_size(chan);
1042
1043 if (chan->fcs == L2CAP_FCS_CRC16)
1044 hlen += L2CAP_FCS_SIZE;
1045
1046 skb = bt_skb_alloc(hlen, GFP_KERNEL);
1047
1048 if (!skb)
1049 return ERR_PTR(-ENOMEM);
1050
1051 lh = (struct l2cap_hdr *) skb_put(skb, L2CAP_HDR_SIZE);
1052 lh->len = cpu_to_le16(hlen - L2CAP_HDR_SIZE);
1053 lh->cid = cpu_to_le16(chan->dcid);
1054
1055 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
1056 put_unaligned_le32(control, skb_put(skb, L2CAP_EXT_CTRL_SIZE));
1057 else
1058 put_unaligned_le16(control, skb_put(skb, L2CAP_ENH_CTRL_SIZE));
1059
1060 if (chan->fcs == L2CAP_FCS_CRC16) {
1061 u16 fcs = crc16(0, (u8 *)skb->data, skb->len);
1062 put_unaligned_le16(fcs, skb_put(skb, L2CAP_FCS_SIZE));
1063 }
1064
1065 skb->priority = HCI_PRIO_MAX;
1066 return skb;
1067}
1068
1069static void l2cap_send_sframe(struct l2cap_chan *chan,
1070 struct l2cap_ctrl *control)
1071{
1072 struct sk_buff *skb;
1073 u32 control_field;
1074
1075 BT_DBG("chan %p, control %p", chan, control);
1076
1077 if (!control->sframe)
1078 return;
1079
1080 if (__chan_is_moving(chan))
1081 return;
1082
1083 if (test_and_clear_bit(CONN_SEND_FBIT, &chan->conn_state) &&
1084 !control->poll)
1085 control->final = 1;
1086
1087 if (control->super == L2CAP_SUPER_RR)
1088 clear_bit(CONN_RNR_SENT, &chan->conn_state);
1089 else if (control->super == L2CAP_SUPER_RNR)
1090 set_bit(CONN_RNR_SENT, &chan->conn_state);
1091
1092 if (control->super != L2CAP_SUPER_SREJ) {
1093 chan->last_acked_seq = control->reqseq;
1094 __clear_ack_timer(chan);
1095 }
1096
1097 BT_DBG("reqseq %d, final %d, poll %d, super %d", control->reqseq,
1098 control->final, control->poll, control->super);
1099
1100 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
1101 control_field = __pack_extended_control(control);
1102 else
1103 control_field = __pack_enhanced_control(control);
1104
1105 skb = l2cap_create_sframe_pdu(chan, control_field);
1106 if (!IS_ERR(skb))
1107 l2cap_do_send(chan, skb);
1108}
1109
1110static void l2cap_send_rr_or_rnr(struct l2cap_chan *chan, bool poll)
1111{
1112 struct l2cap_ctrl control;
1113
1114 BT_DBG("chan %p, poll %d", chan, poll);
1115
1116 memset(&control, 0, sizeof(control));
1117 control.sframe = 1;
1118 control.poll = poll;
1119
1120 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state))
1121 control.super = L2CAP_SUPER_RNR;
1122 else
1123 control.super = L2CAP_SUPER_RR;
1124
1125 control.reqseq = chan->buffer_seq;
1126 l2cap_send_sframe(chan, &control);
1127}
1128
1129static inline int __l2cap_no_conn_pending(struct l2cap_chan *chan)
1130{
1131 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED)
1132 return true;
1133
1134 return !test_bit(CONF_CONNECT_PEND, &chan->conf_state);
1135}
1136
1137static bool __amp_capable(struct l2cap_chan *chan)
1138{
1139 struct l2cap_conn *conn = chan->conn;
1140 struct hci_dev *hdev;
1141 bool amp_available = false;
1142
1143 if (!(conn->local_fixed_chan & L2CAP_FC_A2MP))
1144 return false;
1145
1146 if (!(conn->remote_fixed_chan & L2CAP_FC_A2MP))
1147 return false;
1148
1149 read_lock(&hci_dev_list_lock);
1150 list_for_each_entry(hdev, &hci_dev_list, list) {
1151 if (hdev->amp_type != AMP_TYPE_BREDR &&
1152 test_bit(HCI_UP, &hdev->flags)) {
1153 amp_available = true;
1154 break;
1155 }
1156 }
1157 read_unlock(&hci_dev_list_lock);
1158
1159 if (chan->chan_policy == BT_CHANNEL_POLICY_AMP_PREFERRED)
1160 return amp_available;
1161
1162 return false;
1163}
1164
1165static bool l2cap_check_efs(struct l2cap_chan *chan)
1166{
1167 /* Check EFS parameters */
1168 return true;
1169}
1170
1171void l2cap_send_conn_req(struct l2cap_chan *chan)
1172{
1173 struct l2cap_conn *conn = chan->conn;
1174 struct l2cap_conn_req req;
1175
1176 req.scid = cpu_to_le16(chan->scid);
1177 req.psm = chan->psm;
1178
1179 chan->ident = l2cap_get_ident(conn);
1180
1181 set_bit(CONF_CONNECT_PEND, &chan->conf_state);
1182
1183 l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_REQ, sizeof(req), &req);
1184}
1185
1186static void l2cap_send_create_chan_req(struct l2cap_chan *chan, u8 amp_id)
1187{
1188 struct l2cap_create_chan_req req;
1189 req.scid = cpu_to_le16(chan->scid);
1190 req.psm = chan->psm;
1191 req.amp_id = amp_id;
1192
1193 chan->ident = l2cap_get_ident(chan->conn);
1194
1195 l2cap_send_cmd(chan->conn, chan->ident, L2CAP_CREATE_CHAN_REQ,
1196 sizeof(req), &req);
1197}
1198
1199static void l2cap_move_setup(struct l2cap_chan *chan)
1200{
1201 struct sk_buff *skb;
1202
1203 BT_DBG("chan %p", chan);
1204
1205 if (chan->mode != L2CAP_MODE_ERTM)
1206 return;
1207
1208 __clear_retrans_timer(chan);
1209 __clear_monitor_timer(chan);
1210 __clear_ack_timer(chan);
1211
1212 chan->retry_count = 0;
1213 skb_queue_walk(&chan->tx_q, skb) {
1214 if (bt_cb(skb)->l2cap.retries)
1215 bt_cb(skb)->l2cap.retries = 1;
1216 else
1217 break;
1218 }
1219
1220 chan->expected_tx_seq = chan->buffer_seq;
1221
1222 clear_bit(CONN_REJ_ACT, &chan->conn_state);
1223 clear_bit(CONN_SREJ_ACT, &chan->conn_state);
1224 l2cap_seq_list_clear(&chan->retrans_list);
1225 l2cap_seq_list_clear(&chan->srej_list);
1226 skb_queue_purge(&chan->srej_q);
1227
1228 chan->tx_state = L2CAP_TX_STATE_XMIT;
1229 chan->rx_state = L2CAP_RX_STATE_MOVE;
1230
1231 set_bit(CONN_REMOTE_BUSY, &chan->conn_state);
1232}
1233
1234static void l2cap_move_done(struct l2cap_chan *chan)
1235{
1236 u8 move_role = chan->move_role;
1237 BT_DBG("chan %p", chan);
1238
1239 chan->move_state = L2CAP_MOVE_STABLE;
1240 chan->move_role = L2CAP_MOVE_ROLE_NONE;
1241
1242 if (chan->mode != L2CAP_MODE_ERTM)
1243 return;
1244
1245 switch (move_role) {
1246 case L2CAP_MOVE_ROLE_INITIATOR:
1247 l2cap_tx(chan, NULL, NULL, L2CAP_EV_EXPLICIT_POLL);
1248 chan->rx_state = L2CAP_RX_STATE_WAIT_F;
1249 break;
1250 case L2CAP_MOVE_ROLE_RESPONDER:
1251 chan->rx_state = L2CAP_RX_STATE_WAIT_P;
1252 break;
1253 }
1254}
1255
1256static void l2cap_chan_ready(struct l2cap_chan *chan)
1257{
1258 /* The channel may have already been flagged as connected in
1259 * case of receiving data before the L2CAP info req/rsp
1260 * procedure is complete.
1261 */
1262 if (chan->state == BT_CONNECTED)
1263 return;
1264
1265 /* This clears all conf flags, including CONF_NOT_COMPLETE */
1266 chan->conf_state = 0;
1267 __clear_chan_timer(chan);
1268
1269 if (chan->mode == L2CAP_MODE_LE_FLOWCTL && !chan->tx_credits)
1270 chan->ops->suspend(chan);
1271
1272 chan->state = BT_CONNECTED;
1273
1274 chan->ops->ready(chan);
1275}
1276
1277static void l2cap_le_connect(struct l2cap_chan *chan)
1278{
1279 struct l2cap_conn *conn = chan->conn;
1280 struct l2cap_le_conn_req req;
1281
1282 if (test_and_set_bit(FLAG_LE_CONN_REQ_SENT, &chan->flags))
1283 return;
1284
1285 req.psm = chan->psm;
1286 req.scid = cpu_to_le16(chan->scid);
1287 req.mtu = cpu_to_le16(chan->imtu);
1288 req.mps = cpu_to_le16(chan->mps);
1289 req.credits = cpu_to_le16(chan->rx_credits);
1290
1291 chan->ident = l2cap_get_ident(conn);
1292
1293 l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CONN_REQ,
1294 sizeof(req), &req);
1295}
1296
1297static void l2cap_le_start(struct l2cap_chan *chan)
1298{
1299 struct l2cap_conn *conn = chan->conn;
1300
1301 if (!smp_conn_security(conn->hcon, chan->sec_level))
1302 return;
1303
1304 if (!chan->psm) {
1305 l2cap_chan_ready(chan);
1306 return;
1307 }
1308
1309 if (chan->state == BT_CONNECT)
1310 l2cap_le_connect(chan);
1311}
1312
1313static void l2cap_start_connection(struct l2cap_chan *chan)
1314{
1315 if (__amp_capable(chan)) {
1316 BT_DBG("chan %p AMP capable: discover AMPs", chan);
1317 a2mp_discover_amp(chan);
1318 } else if (chan->conn->hcon->type == LE_LINK) {
1319 l2cap_le_start(chan);
1320 } else {
1321 l2cap_send_conn_req(chan);
1322 }
1323}
1324
1325static void l2cap_request_info(struct l2cap_conn *conn)
1326{
1327 struct l2cap_info_req req;
1328
1329 if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT)
1330 return;
1331
1332 req.type = cpu_to_le16(L2CAP_IT_FEAT_MASK);
1333
1334 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_SENT;
1335 conn->info_ident = l2cap_get_ident(conn);
1336
1337 schedule_delayed_work(&conn->info_timer, L2CAP_INFO_TIMEOUT);
1338
1339 l2cap_send_cmd(conn, conn->info_ident, L2CAP_INFO_REQ,
1340 sizeof(req), &req);
1341}
1342
1343static void l2cap_do_start(struct l2cap_chan *chan)
1344{
1345 struct l2cap_conn *conn = chan->conn;
1346
1347 if (conn->hcon->type == LE_LINK) {
1348 l2cap_le_start(chan);
1349 return;
1350 }
1351
1352 if (!(conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT)) {
1353 l2cap_request_info(conn);
1354 return;
1355 }
1356
1357 if (!(conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE))
1358 return;
1359
1360 if (l2cap_chan_check_security(chan, true) &&
1361 __l2cap_no_conn_pending(chan))
1362 l2cap_start_connection(chan);
1363}
1364
1365static inline int l2cap_mode_supported(__u8 mode, __u32 feat_mask)
1366{
1367 u32 local_feat_mask = l2cap_feat_mask;
1368 if (!disable_ertm)
1369 local_feat_mask |= L2CAP_FEAT_ERTM | L2CAP_FEAT_STREAMING;
1370
1371 switch (mode) {
1372 case L2CAP_MODE_ERTM:
1373 return L2CAP_FEAT_ERTM & feat_mask & local_feat_mask;
1374 case L2CAP_MODE_STREAMING:
1375 return L2CAP_FEAT_STREAMING & feat_mask & local_feat_mask;
1376 default:
1377 return 0x00;
1378 }
1379}
1380
1381static void l2cap_send_disconn_req(struct l2cap_chan *chan, int err)
1382{
1383 struct l2cap_conn *conn = chan->conn;
1384 struct l2cap_disconn_req req;
1385
1386 if (!conn)
1387 return;
1388
1389 if (chan->mode == L2CAP_MODE_ERTM && chan->state == BT_CONNECTED) {
1390 __clear_retrans_timer(chan);
1391 __clear_monitor_timer(chan);
1392 __clear_ack_timer(chan);
1393 }
1394
1395 if (chan->scid == L2CAP_CID_A2MP) {
1396 l2cap_state_change(chan, BT_DISCONN);
1397 return;
1398 }
1399
1400 req.dcid = cpu_to_le16(chan->dcid);
1401 req.scid = cpu_to_le16(chan->scid);
1402 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_DISCONN_REQ,
1403 sizeof(req), &req);
1404
1405 l2cap_state_change_and_error(chan, BT_DISCONN, err);
1406}
1407
1408/* ---- L2CAP connections ---- */
1409static void l2cap_conn_start(struct l2cap_conn *conn)
1410{
1411 struct l2cap_chan *chan, *tmp;
1412
1413 BT_DBG("conn %p", conn);
1414
1415 mutex_lock(&conn->chan_lock);
1416
1417 list_for_each_entry_safe(chan, tmp, &conn->chan_l, list) {
1418 l2cap_chan_lock(chan);
1419
1420 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) {
1421 l2cap_chan_ready(chan);
1422 l2cap_chan_unlock(chan);
1423 continue;
1424 }
1425
1426 if (chan->state == BT_CONNECT) {
1427 if (!l2cap_chan_check_security(chan, true) ||
1428 !__l2cap_no_conn_pending(chan)) {
1429 l2cap_chan_unlock(chan);
1430 continue;
1431 }
1432
1433 if (!l2cap_mode_supported(chan->mode, conn->feat_mask)
1434 && test_bit(CONF_STATE2_DEVICE,
1435 &chan->conf_state)) {
1436 l2cap_chan_close(chan, ECONNRESET);
1437 l2cap_chan_unlock(chan);
1438 continue;
1439 }
1440
1441 l2cap_start_connection(chan);
1442
1443 } else if (chan->state == BT_CONNECT2) {
1444 struct l2cap_conn_rsp rsp;
1445 char buf[128];
1446 rsp.scid = cpu_to_le16(chan->dcid);
1447 rsp.dcid = cpu_to_le16(chan->scid);
1448
1449 if (l2cap_chan_check_security(chan, false)) {
1450 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) {
1451 rsp.result = cpu_to_le16(L2CAP_CR_PEND);
1452 rsp.status = cpu_to_le16(L2CAP_CS_AUTHOR_PEND);
1453 chan->ops->defer(chan);
1454
1455 } else {
1456 l2cap_state_change(chan, BT_CONFIG);
1457 rsp.result = cpu_to_le16(L2CAP_CR_SUCCESS);
1458 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
1459 }
1460 } else {
1461 rsp.result = cpu_to_le16(L2CAP_CR_PEND);
1462 rsp.status = cpu_to_le16(L2CAP_CS_AUTHEN_PEND);
1463 }
1464
1465 l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_RSP,
1466 sizeof(rsp), &rsp);
1467
1468 if (test_bit(CONF_REQ_SENT, &chan->conf_state) ||
1469 rsp.result != L2CAP_CR_SUCCESS) {
1470 l2cap_chan_unlock(chan);
1471 continue;
1472 }
1473
1474 set_bit(CONF_REQ_SENT, &chan->conf_state);
1475 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
1476 l2cap_build_conf_req(chan, buf), buf);
1477 chan->num_conf_req++;
1478 }
1479
1480 l2cap_chan_unlock(chan);
1481 }
1482
1483 mutex_unlock(&conn->chan_lock);
1484}
1485
1486static void l2cap_le_conn_ready(struct l2cap_conn *conn)
1487{
1488 struct hci_conn *hcon = conn->hcon;
1489 struct hci_dev *hdev = hcon->hdev;
1490
1491 BT_DBG("%s conn %p", hdev->name, conn);
1492
1493 /* For outgoing pairing which doesn't necessarily have an
1494 * associated socket (e.g. mgmt_pair_device).
1495 */
1496 if (hcon->out)
1497 smp_conn_security(hcon, hcon->pending_sec_level);
1498
1499 /* For LE slave connections, make sure the connection interval
1500 * is in the range of the minium and maximum interval that has
1501 * been configured for this connection. If not, then trigger
1502 * the connection update procedure.
1503 */
1504 if (hcon->role == HCI_ROLE_SLAVE &&
1505 (hcon->le_conn_interval < hcon->le_conn_min_interval ||
1506 hcon->le_conn_interval > hcon->le_conn_max_interval)) {
1507 struct l2cap_conn_param_update_req req;
1508
1509 req.min = cpu_to_le16(hcon->le_conn_min_interval);
1510 req.max = cpu_to_le16(hcon->le_conn_max_interval);
1511 req.latency = cpu_to_le16(hcon->le_conn_latency);
1512 req.to_multiplier = cpu_to_le16(hcon->le_supv_timeout);
1513
1514 l2cap_send_cmd(conn, l2cap_get_ident(conn),
1515 L2CAP_CONN_PARAM_UPDATE_REQ, sizeof(req), &req);
1516 }
1517}
1518
1519static void l2cap_conn_ready(struct l2cap_conn *conn)
1520{
1521 struct l2cap_chan *chan;
1522 struct hci_conn *hcon = conn->hcon;
1523
1524 BT_DBG("conn %p", conn);
1525
1526 if (hcon->type == ACL_LINK)
1527 l2cap_request_info(conn);
1528
1529 mutex_lock(&conn->chan_lock);
1530
1531 list_for_each_entry(chan, &conn->chan_l, list) {
1532
1533 l2cap_chan_lock(chan);
1534
1535 if (chan->scid == L2CAP_CID_A2MP) {
1536 l2cap_chan_unlock(chan);
1537 continue;
1538 }
1539
1540 if (hcon->type == LE_LINK) {
1541 l2cap_le_start(chan);
1542 } else if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) {
1543 if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE)
1544 l2cap_chan_ready(chan);
1545 } else if (chan->state == BT_CONNECT) {
1546 l2cap_do_start(chan);
1547 }
1548
1549 l2cap_chan_unlock(chan);
1550 }
1551
1552 mutex_unlock(&conn->chan_lock);
1553
1554 if (hcon->type == LE_LINK)
1555 l2cap_le_conn_ready(conn);
1556
1557 queue_work(hcon->hdev->workqueue, &conn->pending_rx_work);
1558}
1559
1560/* Notify sockets that we cannot guaranty reliability anymore */
1561static void l2cap_conn_unreliable(struct l2cap_conn *conn, int err)
1562{
1563 struct l2cap_chan *chan;
1564
1565 BT_DBG("conn %p", conn);
1566
1567 mutex_lock(&conn->chan_lock);
1568
1569 list_for_each_entry(chan, &conn->chan_l, list) {
1570 if (test_bit(FLAG_FORCE_RELIABLE, &chan->flags))
1571 l2cap_chan_set_err(chan, err);
1572 }
1573
1574 mutex_unlock(&conn->chan_lock);
1575}
1576
1577static void l2cap_info_timeout(struct work_struct *work)
1578{
1579 struct l2cap_conn *conn = container_of(work, struct l2cap_conn,
1580 info_timer.work);
1581
1582 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
1583 conn->info_ident = 0;
1584
1585 l2cap_conn_start(conn);
1586}
1587
1588/*
1589 * l2cap_user
1590 * External modules can register l2cap_user objects on l2cap_conn. The ->probe
1591 * callback is called during registration. The ->remove callback is called
1592 * during unregistration.
1593 * An l2cap_user object can either be explicitly unregistered or when the
1594 * underlying l2cap_conn object is deleted. This guarantees that l2cap->hcon,
1595 * l2cap->hchan, .. are valid as long as the remove callback hasn't been called.
1596 * External modules must own a reference to the l2cap_conn object if they intend
1597 * to call l2cap_unregister_user(). The l2cap_conn object might get destroyed at
1598 * any time if they don't.
1599 */
1600
1601int l2cap_register_user(struct l2cap_conn *conn, struct l2cap_user *user)
1602{
1603 struct hci_dev *hdev = conn->hcon->hdev;
1604 int ret;
1605
1606 /* We need to check whether l2cap_conn is registered. If it is not, we
1607 * must not register the l2cap_user. l2cap_conn_del() is unregisters
1608 * l2cap_conn objects, but doesn't provide its own locking. Instead, it
1609 * relies on the parent hci_conn object to be locked. This itself relies
1610 * on the hci_dev object to be locked. So we must lock the hci device
1611 * here, too. */
1612
1613 hci_dev_lock(hdev);
1614
1615 if (!list_empty(&user->list)) {
1616 ret = -EINVAL;
1617 goto out_unlock;
1618 }
1619
1620 /* conn->hchan is NULL after l2cap_conn_del() was called */
1621 if (!conn->hchan) {
1622 ret = -ENODEV;
1623 goto out_unlock;
1624 }
1625
1626 ret = user->probe(conn, user);
1627 if (ret)
1628 goto out_unlock;
1629
1630 list_add(&user->list, &conn->users);
1631 ret = 0;
1632
1633out_unlock:
1634 hci_dev_unlock(hdev);
1635 return ret;
1636}
1637EXPORT_SYMBOL(l2cap_register_user);
1638
1639void l2cap_unregister_user(struct l2cap_conn *conn, struct l2cap_user *user)
1640{
1641 struct hci_dev *hdev = conn->hcon->hdev;
1642
1643 hci_dev_lock(hdev);
1644
1645 if (list_empty(&user->list))
1646 goto out_unlock;
1647
1648 list_del_init(&user->list);
1649 user->remove(conn, user);
1650
1651out_unlock:
1652 hci_dev_unlock(hdev);
1653}
1654EXPORT_SYMBOL(l2cap_unregister_user);
1655
1656static void l2cap_unregister_all_users(struct l2cap_conn *conn)
1657{
1658 struct l2cap_user *user;
1659
1660 while (!list_empty(&conn->users)) {
1661 user = list_first_entry(&conn->users, struct l2cap_user, list);
1662 list_del_init(&user->list);
1663 user->remove(conn, user);
1664 }
1665}
1666
1667static void l2cap_conn_del(struct hci_conn *hcon, int err)
1668{
1669 struct l2cap_conn *conn = hcon->l2cap_data;
1670 struct l2cap_chan *chan, *l;
1671
1672 if (!conn)
1673 return;
1674
1675 BT_DBG("hcon %p conn %p, err %d", hcon, conn, err);
1676
1677 kfree_skb(conn->rx_skb);
1678
1679 skb_queue_purge(&conn->pending_rx);
1680
1681 /* We can not call flush_work(&conn->pending_rx_work) here since we
1682 * might block if we are running on a worker from the same workqueue
1683 * pending_rx_work is waiting on.
1684 */
1685 if (work_pending(&conn->pending_rx_work))
1686 cancel_work_sync(&conn->pending_rx_work);
1687
1688 if (work_pending(&conn->id_addr_update_work))
1689 cancel_work_sync(&conn->id_addr_update_work);
1690
1691 l2cap_unregister_all_users(conn);
1692
1693 /* Force the connection to be immediately dropped */
1694 hcon->disc_timeout = 0;
1695
1696 mutex_lock(&conn->chan_lock);
1697
1698 /* Kill channels */
1699 list_for_each_entry_safe(chan, l, &conn->chan_l, list) {
1700 l2cap_chan_hold(chan);
1701 l2cap_chan_lock(chan);
1702
1703 l2cap_chan_del(chan, err);
1704
1705 l2cap_chan_unlock(chan);
1706
1707 chan->ops->close(chan);
1708 l2cap_chan_put(chan);
1709 }
1710
1711 mutex_unlock(&conn->chan_lock);
1712
1713 hci_chan_del(conn->hchan);
1714
1715 if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT)
1716 cancel_delayed_work_sync(&conn->info_timer);
1717
1718 hcon->l2cap_data = NULL;
1719 conn->hchan = NULL;
1720 l2cap_conn_put(conn);
1721}
1722
1723static void l2cap_conn_free(struct kref *ref)
1724{
1725 struct l2cap_conn *conn = container_of(ref, struct l2cap_conn, ref);
1726
1727 hci_conn_put(conn->hcon);
1728 kfree(conn);
1729}
1730
1731struct l2cap_conn *l2cap_conn_get(struct l2cap_conn *conn)
1732{
1733 kref_get(&conn->ref);
1734 return conn;
1735}
1736EXPORT_SYMBOL(l2cap_conn_get);
1737
1738void l2cap_conn_put(struct l2cap_conn *conn)
1739{
1740 kref_put(&conn->ref, l2cap_conn_free);
1741}
1742EXPORT_SYMBOL(l2cap_conn_put);
1743
1744/* ---- Socket interface ---- */
1745
1746/* Find socket with psm and source / destination bdaddr.
1747 * Returns closest match.
1748 */
1749static struct l2cap_chan *l2cap_global_chan_by_psm(int state, __le16 psm,
1750 bdaddr_t *src,
1751 bdaddr_t *dst,
1752 u8 link_type)
1753{
1754 struct l2cap_chan *c, *c1 = NULL;
1755
1756 read_lock(&chan_list_lock);
1757
1758 list_for_each_entry(c, &chan_list, global_l) {
1759 if (state && c->state != state)
1760 continue;
1761
1762 if (link_type == ACL_LINK && c->src_type != BDADDR_BREDR)
1763 continue;
1764
1765 if (link_type == LE_LINK && c->src_type == BDADDR_BREDR)
1766 continue;
1767
1768 if (c->psm == psm) {
1769 int src_match, dst_match;
1770 int src_any, dst_any;
1771
1772 /* Exact match. */
1773 src_match = !bacmp(&c->src, src);
1774 dst_match = !bacmp(&c->dst, dst);
1775 if (src_match && dst_match) {
1776 l2cap_chan_hold(c);
1777 read_unlock(&chan_list_lock);
1778 return c;
1779 }
1780
1781 /* Closest match */
1782 src_any = !bacmp(&c->src, BDADDR_ANY);
1783 dst_any = !bacmp(&c->dst, BDADDR_ANY);
1784 if ((src_match && dst_any) || (src_any && dst_match) ||
1785 (src_any && dst_any))
1786 c1 = c;
1787 }
1788 }
1789
1790 if (c1)
1791 l2cap_chan_hold(c1);
1792
1793 read_unlock(&chan_list_lock);
1794
1795 return c1;
1796}
1797
1798static void l2cap_monitor_timeout(struct work_struct *work)
1799{
1800 struct l2cap_chan *chan = container_of(work, struct l2cap_chan,
1801 monitor_timer.work);
1802
1803 BT_DBG("chan %p", chan);
1804
1805 l2cap_chan_lock(chan);
1806
1807 if (!chan->conn) {
1808 l2cap_chan_unlock(chan);
1809 l2cap_chan_put(chan);
1810 return;
1811 }
1812
1813 l2cap_tx(chan, NULL, NULL, L2CAP_EV_MONITOR_TO);
1814
1815 l2cap_chan_unlock(chan);
1816 l2cap_chan_put(chan);
1817}
1818
1819static void l2cap_retrans_timeout(struct work_struct *work)
1820{
1821 struct l2cap_chan *chan = container_of(work, struct l2cap_chan,
1822 retrans_timer.work);
1823
1824 BT_DBG("chan %p", chan);
1825
1826 l2cap_chan_lock(chan);
1827
1828 if (!chan->conn) {
1829 l2cap_chan_unlock(chan);
1830 l2cap_chan_put(chan);
1831 return;
1832 }
1833
1834 l2cap_tx(chan, NULL, NULL, L2CAP_EV_RETRANS_TO);
1835 l2cap_chan_unlock(chan);
1836 l2cap_chan_put(chan);
1837}
1838
1839static void l2cap_streaming_send(struct l2cap_chan *chan,
1840 struct sk_buff_head *skbs)
1841{
1842 struct sk_buff *skb;
1843 struct l2cap_ctrl *control;
1844
1845 BT_DBG("chan %p, skbs %p", chan, skbs);
1846
1847 if (__chan_is_moving(chan))
1848 return;
1849
1850 skb_queue_splice_tail_init(skbs, &chan->tx_q);
1851
1852 while (!skb_queue_empty(&chan->tx_q)) {
1853
1854 skb = skb_dequeue(&chan->tx_q);
1855
1856 bt_cb(skb)->l2cap.retries = 1;
1857 control = &bt_cb(skb)->l2cap;
1858
1859 control->reqseq = 0;
1860 control->txseq = chan->next_tx_seq;
1861
1862 __pack_control(chan, control, skb);
1863
1864 if (chan->fcs == L2CAP_FCS_CRC16) {
1865 u16 fcs = crc16(0, (u8 *) skb->data, skb->len);
1866 put_unaligned_le16(fcs, skb_put(skb, L2CAP_FCS_SIZE));
1867 }
1868
1869 l2cap_do_send(chan, skb);
1870
1871 BT_DBG("Sent txseq %u", control->txseq);
1872
1873 chan->next_tx_seq = __next_seq(chan, chan->next_tx_seq);
1874 chan->frames_sent++;
1875 }
1876}
1877
1878static int l2cap_ertm_send(struct l2cap_chan *chan)
1879{
1880 struct sk_buff *skb, *tx_skb;
1881 struct l2cap_ctrl *control;
1882 int sent = 0;
1883
1884 BT_DBG("chan %p", chan);
1885
1886 if (chan->state != BT_CONNECTED)
1887 return -ENOTCONN;
1888
1889 if (test_bit(CONN_REMOTE_BUSY, &chan->conn_state))
1890 return 0;
1891
1892 if (__chan_is_moving(chan))
1893 return 0;
1894
1895 while (chan->tx_send_head &&
1896 chan->unacked_frames < chan->remote_tx_win &&
1897 chan->tx_state == L2CAP_TX_STATE_XMIT) {
1898
1899 skb = chan->tx_send_head;
1900
1901 bt_cb(skb)->l2cap.retries = 1;
1902 control = &bt_cb(skb)->l2cap;
1903
1904 if (test_and_clear_bit(CONN_SEND_FBIT, &chan->conn_state))
1905 control->final = 1;
1906
1907 control->reqseq = chan->buffer_seq;
1908 chan->last_acked_seq = chan->buffer_seq;
1909 control->txseq = chan->next_tx_seq;
1910
1911 __pack_control(chan, control, skb);
1912
1913 if (chan->fcs == L2CAP_FCS_CRC16) {
1914 u16 fcs = crc16(0, (u8 *) skb->data, skb->len);
1915 put_unaligned_le16(fcs, skb_put(skb, L2CAP_FCS_SIZE));
1916 }
1917
1918 /* Clone after data has been modified. Data is assumed to be
1919 read-only (for locking purposes) on cloned sk_buffs.
1920 */
1921 tx_skb = skb_clone(skb, GFP_KERNEL);
1922
1923 if (!tx_skb)
1924 break;
1925
1926 __set_retrans_timer(chan);
1927
1928 chan->next_tx_seq = __next_seq(chan, chan->next_tx_seq);
1929 chan->unacked_frames++;
1930 chan->frames_sent++;
1931 sent++;
1932
1933 if (skb_queue_is_last(&chan->tx_q, skb))
1934 chan->tx_send_head = NULL;
1935 else
1936 chan->tx_send_head = skb_queue_next(&chan->tx_q, skb);
1937
1938 l2cap_do_send(chan, tx_skb);
1939 BT_DBG("Sent txseq %u", control->txseq);
1940 }
1941
1942 BT_DBG("Sent %d, %u unacked, %u in ERTM queue", sent,
1943 chan->unacked_frames, skb_queue_len(&chan->tx_q));
1944
1945 return sent;
1946}
1947
1948static void l2cap_ertm_resend(struct l2cap_chan *chan)
1949{
1950 struct l2cap_ctrl control;
1951 struct sk_buff *skb;
1952 struct sk_buff *tx_skb;
1953 u16 seq;
1954
1955 BT_DBG("chan %p", chan);
1956
1957 if (test_bit(CONN_REMOTE_BUSY, &chan->conn_state))
1958 return;
1959
1960 if (__chan_is_moving(chan))
1961 return;
1962
1963 while (chan->retrans_list.head != L2CAP_SEQ_LIST_CLEAR) {
1964 seq = l2cap_seq_list_pop(&chan->retrans_list);
1965
1966 skb = l2cap_ertm_seq_in_queue(&chan->tx_q, seq);
1967 if (!skb) {
1968 BT_DBG("Error: Can't retransmit seq %d, frame missing",
1969 seq);
1970 continue;
1971 }
1972
1973 bt_cb(skb)->l2cap.retries++;
1974 control = bt_cb(skb)->l2cap;
1975
1976 if (chan->max_tx != 0 &&
1977 bt_cb(skb)->l2cap.retries > chan->max_tx) {
1978 BT_DBG("Retry limit exceeded (%d)", chan->max_tx);
1979 l2cap_send_disconn_req(chan, ECONNRESET);
1980 l2cap_seq_list_clear(&chan->retrans_list);
1981 break;
1982 }
1983
1984 control.reqseq = chan->buffer_seq;
1985 if (test_and_clear_bit(CONN_SEND_FBIT, &chan->conn_state))
1986 control.final = 1;
1987 else
1988 control.final = 0;
1989
1990 if (skb_cloned(skb)) {
1991 /* Cloned sk_buffs are read-only, so we need a
1992 * writeable copy
1993 */
1994 tx_skb = skb_copy(skb, GFP_KERNEL);
1995 } else {
1996 tx_skb = skb_clone(skb, GFP_KERNEL);
1997 }
1998
1999 if (!tx_skb) {
2000 l2cap_seq_list_clear(&chan->retrans_list);
2001 break;
2002 }
2003
2004 /* Update skb contents */
2005 if (test_bit(FLAG_EXT_CTRL, &chan->flags)) {
2006 put_unaligned_le32(__pack_extended_control(&control),
2007 tx_skb->data + L2CAP_HDR_SIZE);
2008 } else {
2009 put_unaligned_le16(__pack_enhanced_control(&control),
2010 tx_skb->data + L2CAP_HDR_SIZE);
2011 }
2012
2013 /* Update FCS */
2014 if (chan->fcs == L2CAP_FCS_CRC16) {
2015 u16 fcs = crc16(0, (u8 *) tx_skb->data,
2016 tx_skb->len - L2CAP_FCS_SIZE);
2017 put_unaligned_le16(fcs, skb_tail_pointer(tx_skb) -
2018 L2CAP_FCS_SIZE);
2019 }
2020
2021 l2cap_do_send(chan, tx_skb);
2022
2023 BT_DBG("Resent txseq %d", control.txseq);
2024
2025 chan->last_acked_seq = chan->buffer_seq;
2026 }
2027}
2028
2029static void l2cap_retransmit(struct l2cap_chan *chan,
2030 struct l2cap_ctrl *control)
2031{
2032 BT_DBG("chan %p, control %p", chan, control);
2033
2034 l2cap_seq_list_append(&chan->retrans_list, control->reqseq);
2035 l2cap_ertm_resend(chan);
2036}
2037
2038static void l2cap_retransmit_all(struct l2cap_chan *chan,
2039 struct l2cap_ctrl *control)
2040{
2041 struct sk_buff *skb;
2042
2043 BT_DBG("chan %p, control %p", chan, control);
2044
2045 if (control->poll)
2046 set_bit(CONN_SEND_FBIT, &chan->conn_state);
2047
2048 l2cap_seq_list_clear(&chan->retrans_list);
2049
2050 if (test_bit(CONN_REMOTE_BUSY, &chan->conn_state))
2051 return;
2052
2053 if (chan->unacked_frames) {
2054 skb_queue_walk(&chan->tx_q, skb) {
2055 if (bt_cb(skb)->l2cap.txseq == control->reqseq ||
2056 skb == chan->tx_send_head)
2057 break;
2058 }
2059
2060 skb_queue_walk_from(&chan->tx_q, skb) {
2061 if (skb == chan->tx_send_head)
2062 break;
2063
2064 l2cap_seq_list_append(&chan->retrans_list,
2065 bt_cb(skb)->l2cap.txseq);
2066 }
2067
2068 l2cap_ertm_resend(chan);
2069 }
2070}
2071
2072static void l2cap_send_ack(struct l2cap_chan *chan)
2073{
2074 struct l2cap_ctrl control;
2075 u16 frames_to_ack = __seq_offset(chan, chan->buffer_seq,
2076 chan->last_acked_seq);
2077 int threshold;
2078
2079 BT_DBG("chan %p last_acked_seq %d buffer_seq %d",
2080 chan, chan->last_acked_seq, chan->buffer_seq);
2081
2082 memset(&control, 0, sizeof(control));
2083 control.sframe = 1;
2084
2085 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state) &&
2086 chan->rx_state == L2CAP_RX_STATE_RECV) {
2087 __clear_ack_timer(chan);
2088 control.super = L2CAP_SUPER_RNR;
2089 control.reqseq = chan->buffer_seq;
2090 l2cap_send_sframe(chan, &control);
2091 } else {
2092 if (!test_bit(CONN_REMOTE_BUSY, &chan->conn_state)) {
2093 l2cap_ertm_send(chan);
2094 /* If any i-frames were sent, they included an ack */
2095 if (chan->buffer_seq == chan->last_acked_seq)
2096 frames_to_ack = 0;
2097 }
2098
2099 /* Ack now if the window is 3/4ths full.
2100 * Calculate without mul or div
2101 */
2102 threshold = chan->ack_win;
2103 threshold += threshold << 1;
2104 threshold >>= 2;
2105
2106 BT_DBG("frames_to_ack %u, threshold %d", frames_to_ack,
2107 threshold);
2108
2109 if (frames_to_ack >= threshold) {
2110 __clear_ack_timer(chan);
2111 control.super = L2CAP_SUPER_RR;
2112 control.reqseq = chan->buffer_seq;
2113 l2cap_send_sframe(chan, &control);
2114 frames_to_ack = 0;
2115 }
2116
2117 if (frames_to_ack)
2118 __set_ack_timer(chan);
2119 }
2120}
2121
2122static inline int l2cap_skbuff_fromiovec(struct l2cap_chan *chan,
2123 struct msghdr *msg, int len,
2124 int count, struct sk_buff *skb)
2125{
2126 struct l2cap_conn *conn = chan->conn;
2127 struct sk_buff **frag;
2128 int sent = 0;
2129
2130 if (!copy_from_iter_full(skb_put(skb, count), count, &msg->msg_iter))
2131 return -EFAULT;
2132
2133 sent += count;
2134 len -= count;
2135
2136 /* Continuation fragments (no L2CAP header) */
2137 frag = &skb_shinfo(skb)->frag_list;
2138 while (len) {
2139 struct sk_buff *tmp;
2140
2141 count = min_t(unsigned int, conn->mtu, len);
2142
2143 tmp = chan->ops->alloc_skb(chan, 0, count,
2144 msg->msg_flags & MSG_DONTWAIT);
2145 if (IS_ERR(tmp))
2146 return PTR_ERR(tmp);
2147
2148 *frag = tmp;
2149
2150 if (!copy_from_iter_full(skb_put(*frag, count), count,
2151 &msg->msg_iter))
2152 return -EFAULT;
2153
2154 sent += count;
2155 len -= count;
2156
2157 skb->len += (*frag)->len;
2158 skb->data_len += (*frag)->len;
2159
2160 frag = &(*frag)->next;
2161 }
2162
2163 return sent;
2164}
2165
2166static struct sk_buff *l2cap_create_connless_pdu(struct l2cap_chan *chan,
2167 struct msghdr *msg, size_t len)
2168{
2169 struct l2cap_conn *conn = chan->conn;
2170 struct sk_buff *skb;
2171 int err, count, hlen = L2CAP_HDR_SIZE + L2CAP_PSMLEN_SIZE;
2172 struct l2cap_hdr *lh;
2173
2174 BT_DBG("chan %p psm 0x%2.2x len %zu", chan,
2175 __le16_to_cpu(chan->psm), len);
2176
2177 count = min_t(unsigned int, (conn->mtu - hlen), len);
2178
2179 skb = chan->ops->alloc_skb(chan, hlen, count,
2180 msg->msg_flags & MSG_DONTWAIT);
2181 if (IS_ERR(skb))
2182 return skb;
2183
2184 /* Create L2CAP header */
2185 lh = (struct l2cap_hdr *) skb_put(skb, L2CAP_HDR_SIZE);
2186 lh->cid = cpu_to_le16(chan->dcid);
2187 lh->len = cpu_to_le16(len + L2CAP_PSMLEN_SIZE);
2188 put_unaligned(chan->psm, (__le16 *) skb_put(skb, L2CAP_PSMLEN_SIZE));
2189
2190 err = l2cap_skbuff_fromiovec(chan, msg, len, count, skb);
2191 if (unlikely(err < 0)) {
2192 kfree_skb(skb);
2193 return ERR_PTR(err);
2194 }
2195 return skb;
2196}
2197
2198static struct sk_buff *l2cap_create_basic_pdu(struct l2cap_chan *chan,
2199 struct msghdr *msg, size_t len)
2200{
2201 struct l2cap_conn *conn = chan->conn;
2202 struct sk_buff *skb;
2203 int err, count;
2204 struct l2cap_hdr *lh;
2205
2206 BT_DBG("chan %p len %zu", chan, len);
2207
2208 count = min_t(unsigned int, (conn->mtu - L2CAP_HDR_SIZE), len);
2209
2210 skb = chan->ops->alloc_skb(chan, L2CAP_HDR_SIZE, count,
2211 msg->msg_flags & MSG_DONTWAIT);
2212 if (IS_ERR(skb))
2213 return skb;
2214
2215 /* Create L2CAP header */
2216 lh = (struct l2cap_hdr *) skb_put(skb, L2CAP_HDR_SIZE);
2217 lh->cid = cpu_to_le16(chan->dcid);
2218 lh->len = cpu_to_le16(len);
2219
2220 err = l2cap_skbuff_fromiovec(chan, msg, len, count, skb);
2221 if (unlikely(err < 0)) {
2222 kfree_skb(skb);
2223 return ERR_PTR(err);
2224 }
2225 return skb;
2226}
2227
2228static struct sk_buff *l2cap_create_iframe_pdu(struct l2cap_chan *chan,
2229 struct msghdr *msg, size_t len,
2230 u16 sdulen)
2231{
2232 struct l2cap_conn *conn = chan->conn;
2233 struct sk_buff *skb;
2234 int err, count, hlen;
2235 struct l2cap_hdr *lh;
2236
2237 BT_DBG("chan %p len %zu", chan, len);
2238
2239 if (!conn)
2240 return ERR_PTR(-ENOTCONN);
2241
2242 hlen = __ertm_hdr_size(chan);
2243
2244 if (sdulen)
2245 hlen += L2CAP_SDULEN_SIZE;
2246
2247 if (chan->fcs == L2CAP_FCS_CRC16)
2248 hlen += L2CAP_FCS_SIZE;
2249
2250 count = min_t(unsigned int, (conn->mtu - hlen), len);
2251
2252 skb = chan->ops->alloc_skb(chan, hlen, count,
2253 msg->msg_flags & MSG_DONTWAIT);
2254 if (IS_ERR(skb))
2255 return skb;
2256
2257 /* Create L2CAP header */
2258 lh = (struct l2cap_hdr *) skb_put(skb, L2CAP_HDR_SIZE);
2259 lh->cid = cpu_to_le16(chan->dcid);
2260 lh->len = cpu_to_le16(len + (hlen - L2CAP_HDR_SIZE));
2261
2262 /* Control header is populated later */
2263 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
2264 put_unaligned_le32(0, skb_put(skb, L2CAP_EXT_CTRL_SIZE));
2265 else
2266 put_unaligned_le16(0, skb_put(skb, L2CAP_ENH_CTRL_SIZE));
2267
2268 if (sdulen)
2269 put_unaligned_le16(sdulen, skb_put(skb, L2CAP_SDULEN_SIZE));
2270
2271 err = l2cap_skbuff_fromiovec(chan, msg, len, count, skb);
2272 if (unlikely(err < 0)) {
2273 kfree_skb(skb);
2274 return ERR_PTR(err);
2275 }
2276
2277 bt_cb(skb)->l2cap.fcs = chan->fcs;
2278 bt_cb(skb)->l2cap.retries = 0;
2279 return skb;
2280}
2281
2282static int l2cap_segment_sdu(struct l2cap_chan *chan,
2283 struct sk_buff_head *seg_queue,
2284 struct msghdr *msg, size_t len)
2285{
2286 struct sk_buff *skb;
2287 u16 sdu_len;
2288 size_t pdu_len;
2289 u8 sar;
2290
2291 BT_DBG("chan %p, msg %p, len %zu", chan, msg, len);
2292
2293 /* It is critical that ERTM PDUs fit in a single HCI fragment,
2294 * so fragmented skbs are not used. The HCI layer's handling
2295 * of fragmented skbs is not compatible with ERTM's queueing.
2296 */
2297
2298 /* PDU size is derived from the HCI MTU */
2299 pdu_len = chan->conn->mtu;
2300
2301 /* Constrain PDU size for BR/EDR connections */
2302 if (!chan->hs_hcon)
2303 pdu_len = min_t(size_t, pdu_len, L2CAP_BREDR_MAX_PAYLOAD);
2304
2305 /* Adjust for largest possible L2CAP overhead. */
2306 if (chan->fcs)
2307 pdu_len -= L2CAP_FCS_SIZE;
2308
2309 pdu_len -= __ertm_hdr_size(chan);
2310
2311 /* Remote device may have requested smaller PDUs */
2312 pdu_len = min_t(size_t, pdu_len, chan->remote_mps);
2313
2314 if (len <= pdu_len) {
2315 sar = L2CAP_SAR_UNSEGMENTED;
2316 sdu_len = 0;
2317 pdu_len = len;
2318 } else {
2319 sar = L2CAP_SAR_START;
2320 sdu_len = len;
2321 }
2322
2323 while (len > 0) {
2324 skb = l2cap_create_iframe_pdu(chan, msg, pdu_len, sdu_len);
2325
2326 if (IS_ERR(skb)) {
2327 __skb_queue_purge(seg_queue);
2328 return PTR_ERR(skb);
2329 }
2330
2331 bt_cb(skb)->l2cap.sar = sar;
2332 __skb_queue_tail(seg_queue, skb);
2333
2334 len -= pdu_len;
2335 if (sdu_len)
2336 sdu_len = 0;
2337
2338 if (len <= pdu_len) {
2339 sar = L2CAP_SAR_END;
2340 pdu_len = len;
2341 } else {
2342 sar = L2CAP_SAR_CONTINUE;
2343 }
2344 }
2345
2346 return 0;
2347}
2348
2349static struct sk_buff *l2cap_create_le_flowctl_pdu(struct l2cap_chan *chan,
2350 struct msghdr *msg,
2351 size_t len, u16 sdulen)
2352{
2353 struct l2cap_conn *conn = chan->conn;
2354 struct sk_buff *skb;
2355 int err, count, hlen;
2356 struct l2cap_hdr *lh;
2357
2358 BT_DBG("chan %p len %zu", chan, len);
2359
2360 if (!conn)
2361 return ERR_PTR(-ENOTCONN);
2362
2363 hlen = L2CAP_HDR_SIZE;
2364
2365 if (sdulen)
2366 hlen += L2CAP_SDULEN_SIZE;
2367
2368 count = min_t(unsigned int, (conn->mtu - hlen), len);
2369
2370 skb = chan->ops->alloc_skb(chan, hlen, count,
2371 msg->msg_flags & MSG_DONTWAIT);
2372 if (IS_ERR(skb))
2373 return skb;
2374
2375 /* Create L2CAP header */
2376 lh = (struct l2cap_hdr *) skb_put(skb, L2CAP_HDR_SIZE);
2377 lh->cid = cpu_to_le16(chan->dcid);
2378 lh->len = cpu_to_le16(len + (hlen - L2CAP_HDR_SIZE));
2379
2380 if (sdulen)
2381 put_unaligned_le16(sdulen, skb_put(skb, L2CAP_SDULEN_SIZE));
2382
2383 err = l2cap_skbuff_fromiovec(chan, msg, len, count, skb);
2384 if (unlikely(err < 0)) {
2385 kfree_skb(skb);
2386 return ERR_PTR(err);
2387 }
2388
2389 return skb;
2390}
2391
2392static int l2cap_segment_le_sdu(struct l2cap_chan *chan,
2393 struct sk_buff_head *seg_queue,
2394 struct msghdr *msg, size_t len)
2395{
2396 struct sk_buff *skb;
2397 size_t pdu_len;
2398 u16 sdu_len;
2399
2400 BT_DBG("chan %p, msg %p, len %zu", chan, msg, len);
2401
2402 sdu_len = len;
2403 pdu_len = chan->remote_mps - L2CAP_SDULEN_SIZE;
2404
2405 while (len > 0) {
2406 if (len <= pdu_len)
2407 pdu_len = len;
2408
2409 skb = l2cap_create_le_flowctl_pdu(chan, msg, pdu_len, sdu_len);
2410 if (IS_ERR(skb)) {
2411 __skb_queue_purge(seg_queue);
2412 return PTR_ERR(skb);
2413 }
2414
2415 __skb_queue_tail(seg_queue, skb);
2416
2417 len -= pdu_len;
2418
2419 if (sdu_len) {
2420 sdu_len = 0;
2421 pdu_len += L2CAP_SDULEN_SIZE;
2422 }
2423 }
2424
2425 return 0;
2426}
2427
2428int l2cap_chan_send(struct l2cap_chan *chan, struct msghdr *msg, size_t len)
2429{
2430 struct sk_buff *skb;
2431 int err;
2432 struct sk_buff_head seg_queue;
2433
2434 if (!chan->conn)
2435 return -ENOTCONN;
2436
2437 /* Connectionless channel */
2438 if (chan->chan_type == L2CAP_CHAN_CONN_LESS) {
2439 skb = l2cap_create_connless_pdu(chan, msg, len);
2440 if (IS_ERR(skb))
2441 return PTR_ERR(skb);
2442
2443 /* Channel lock is released before requesting new skb and then
2444 * reacquired thus we need to recheck channel state.
2445 */
2446 if (chan->state != BT_CONNECTED) {
2447 kfree_skb(skb);
2448 return -ENOTCONN;
2449 }
2450
2451 l2cap_do_send(chan, skb);
2452 return len;
2453 }
2454
2455 switch (chan->mode) {
2456 case L2CAP_MODE_LE_FLOWCTL:
2457 /* Check outgoing MTU */
2458 if (len > chan->omtu)
2459 return -EMSGSIZE;
2460
2461 if (!chan->tx_credits)
2462 return -EAGAIN;
2463
2464 __skb_queue_head_init(&seg_queue);
2465
2466 err = l2cap_segment_le_sdu(chan, &seg_queue, msg, len);
2467
2468 if (chan->state != BT_CONNECTED) {
2469 __skb_queue_purge(&seg_queue);
2470 err = -ENOTCONN;
2471 }
2472
2473 if (err)
2474 return err;
2475
2476 skb_queue_splice_tail_init(&seg_queue, &chan->tx_q);
2477
2478 while (chan->tx_credits && !skb_queue_empty(&chan->tx_q)) {
2479 l2cap_do_send(chan, skb_dequeue(&chan->tx_q));
2480 chan->tx_credits--;
2481 }
2482
2483 if (!chan->tx_credits)
2484 chan->ops->suspend(chan);
2485
2486 err = len;
2487
2488 break;
2489
2490 case L2CAP_MODE_BASIC:
2491 /* Check outgoing MTU */
2492 if (len > chan->omtu)
2493 return -EMSGSIZE;
2494
2495 /* Create a basic PDU */
2496 skb = l2cap_create_basic_pdu(chan, msg, len);
2497 if (IS_ERR(skb))
2498 return PTR_ERR(skb);
2499
2500 /* Channel lock is released before requesting new skb and then
2501 * reacquired thus we need to recheck channel state.
2502 */
2503 if (chan->state != BT_CONNECTED) {
2504 kfree_skb(skb);
2505 return -ENOTCONN;
2506 }
2507
2508 l2cap_do_send(chan, skb);
2509 err = len;
2510 break;
2511
2512 case L2CAP_MODE_ERTM:
2513 case L2CAP_MODE_STREAMING:
2514 /* Check outgoing MTU */
2515 if (len > chan->omtu) {
2516 err = -EMSGSIZE;
2517 break;
2518 }
2519
2520 __skb_queue_head_init(&seg_queue);
2521
2522 /* Do segmentation before calling in to the state machine,
2523 * since it's possible to block while waiting for memory
2524 * allocation.
2525 */
2526 err = l2cap_segment_sdu(chan, &seg_queue, msg, len);
2527
2528 /* The channel could have been closed while segmenting,
2529 * check that it is still connected.
2530 */
2531 if (chan->state != BT_CONNECTED) {
2532 __skb_queue_purge(&seg_queue);
2533 err = -ENOTCONN;
2534 }
2535
2536 if (err)
2537 break;
2538
2539 if (chan->mode == L2CAP_MODE_ERTM)
2540 l2cap_tx(chan, NULL, &seg_queue, L2CAP_EV_DATA_REQUEST);
2541 else
2542 l2cap_streaming_send(chan, &seg_queue);
2543
2544 err = len;
2545
2546 /* If the skbs were not queued for sending, they'll still be in
2547 * seg_queue and need to be purged.
2548 */
2549 __skb_queue_purge(&seg_queue);
2550 break;
2551
2552 default:
2553 BT_DBG("bad state %1.1x", chan->mode);
2554 err = -EBADFD;
2555 }
2556
2557 return err;
2558}
2559EXPORT_SYMBOL_GPL(l2cap_chan_send);
2560
2561static void l2cap_send_srej(struct l2cap_chan *chan, u16 txseq)
2562{
2563 struct l2cap_ctrl control;
2564 u16 seq;
2565
2566 BT_DBG("chan %p, txseq %u", chan, txseq);
2567
2568 memset(&control, 0, sizeof(control));
2569 control.sframe = 1;
2570 control.super = L2CAP_SUPER_SREJ;
2571
2572 for (seq = chan->expected_tx_seq; seq != txseq;
2573 seq = __next_seq(chan, seq)) {
2574 if (!l2cap_ertm_seq_in_queue(&chan->srej_q, seq)) {
2575 control.reqseq = seq;
2576 l2cap_send_sframe(chan, &control);
2577 l2cap_seq_list_append(&chan->srej_list, seq);
2578 }
2579 }
2580
2581 chan->expected_tx_seq = __next_seq(chan, txseq);
2582}
2583
2584static void l2cap_send_srej_tail(struct l2cap_chan *chan)
2585{
2586 struct l2cap_ctrl control;
2587
2588 BT_DBG("chan %p", chan);
2589
2590 if (chan->srej_list.tail == L2CAP_SEQ_LIST_CLEAR)
2591 return;
2592
2593 memset(&control, 0, sizeof(control));
2594 control.sframe = 1;
2595 control.super = L2CAP_SUPER_SREJ;
2596 control.reqseq = chan->srej_list.tail;
2597 l2cap_send_sframe(chan, &control);
2598}
2599
2600static void l2cap_send_srej_list(struct l2cap_chan *chan, u16 txseq)
2601{
2602 struct l2cap_ctrl control;
2603 u16 initial_head;
2604 u16 seq;
2605
2606 BT_DBG("chan %p, txseq %u", chan, txseq);
2607
2608 memset(&control, 0, sizeof(control));
2609 control.sframe = 1;
2610 control.super = L2CAP_SUPER_SREJ;
2611
2612 /* Capture initial list head to allow only one pass through the list. */
2613 initial_head = chan->srej_list.head;
2614
2615 do {
2616 seq = l2cap_seq_list_pop(&chan->srej_list);
2617 if (seq == txseq || seq == L2CAP_SEQ_LIST_CLEAR)
2618 break;
2619
2620 control.reqseq = seq;
2621 l2cap_send_sframe(chan, &control);
2622 l2cap_seq_list_append(&chan->srej_list, seq);
2623 } while (chan->srej_list.head != initial_head);
2624}
2625
2626static void l2cap_process_reqseq(struct l2cap_chan *chan, u16 reqseq)
2627{
2628 struct sk_buff *acked_skb;
2629 u16 ackseq;
2630
2631 BT_DBG("chan %p, reqseq %u", chan, reqseq);
2632
2633 if (chan->unacked_frames == 0 || reqseq == chan->expected_ack_seq)
2634 return;
2635
2636 BT_DBG("expected_ack_seq %u, unacked_frames %u",
2637 chan->expected_ack_seq, chan->unacked_frames);
2638
2639 for (ackseq = chan->expected_ack_seq; ackseq != reqseq;
2640 ackseq = __next_seq(chan, ackseq)) {
2641
2642 acked_skb = l2cap_ertm_seq_in_queue(&chan->tx_q, ackseq);
2643 if (acked_skb) {
2644 skb_unlink(acked_skb, &chan->tx_q);
2645 kfree_skb(acked_skb);
2646 chan->unacked_frames--;
2647 }
2648 }
2649
2650 chan->expected_ack_seq = reqseq;
2651
2652 if (chan->unacked_frames == 0)
2653 __clear_retrans_timer(chan);
2654
2655 BT_DBG("unacked_frames %u", chan->unacked_frames);
2656}
2657
2658static void l2cap_abort_rx_srej_sent(struct l2cap_chan *chan)
2659{
2660 BT_DBG("chan %p", chan);
2661
2662 chan->expected_tx_seq = chan->buffer_seq;
2663 l2cap_seq_list_clear(&chan->srej_list);
2664 skb_queue_purge(&chan->srej_q);
2665 chan->rx_state = L2CAP_RX_STATE_RECV;
2666}
2667
2668static void l2cap_tx_state_xmit(struct l2cap_chan *chan,
2669 struct l2cap_ctrl *control,
2670 struct sk_buff_head *skbs, u8 event)
2671{
2672 BT_DBG("chan %p, control %p, skbs %p, event %d", chan, control, skbs,
2673 event);
2674
2675 switch (event) {
2676 case L2CAP_EV_DATA_REQUEST:
2677 if (chan->tx_send_head == NULL)
2678 chan->tx_send_head = skb_peek(skbs);
2679
2680 skb_queue_splice_tail_init(skbs, &chan->tx_q);
2681 l2cap_ertm_send(chan);
2682 break;
2683 case L2CAP_EV_LOCAL_BUSY_DETECTED:
2684 BT_DBG("Enter LOCAL_BUSY");
2685 set_bit(CONN_LOCAL_BUSY, &chan->conn_state);
2686
2687 if (chan->rx_state == L2CAP_RX_STATE_SREJ_SENT) {
2688 /* The SREJ_SENT state must be aborted if we are to
2689 * enter the LOCAL_BUSY state.
2690 */
2691 l2cap_abort_rx_srej_sent(chan);
2692 }
2693
2694 l2cap_send_ack(chan);
2695
2696 break;
2697 case L2CAP_EV_LOCAL_BUSY_CLEAR:
2698 BT_DBG("Exit LOCAL_BUSY");
2699 clear_bit(CONN_LOCAL_BUSY, &chan->conn_state);
2700
2701 if (test_bit(CONN_RNR_SENT, &chan->conn_state)) {
2702 struct l2cap_ctrl local_control;
2703
2704 memset(&local_control, 0, sizeof(local_control));
2705 local_control.sframe = 1;
2706 local_control.super = L2CAP_SUPER_RR;
2707 local_control.poll = 1;
2708 local_control.reqseq = chan->buffer_seq;
2709 l2cap_send_sframe(chan, &local_control);
2710
2711 chan->retry_count = 1;
2712 __set_monitor_timer(chan);
2713 chan->tx_state = L2CAP_TX_STATE_WAIT_F;
2714 }
2715 break;
2716 case L2CAP_EV_RECV_REQSEQ_AND_FBIT:
2717 l2cap_process_reqseq(chan, control->reqseq);
2718 break;
2719 case L2CAP_EV_EXPLICIT_POLL:
2720 l2cap_send_rr_or_rnr(chan, 1);
2721 chan->retry_count = 1;
2722 __set_monitor_timer(chan);
2723 __clear_ack_timer(chan);
2724 chan->tx_state = L2CAP_TX_STATE_WAIT_F;
2725 break;
2726 case L2CAP_EV_RETRANS_TO:
2727 l2cap_send_rr_or_rnr(chan, 1);
2728 chan->retry_count = 1;
2729 __set_monitor_timer(chan);
2730 chan->tx_state = L2CAP_TX_STATE_WAIT_F;
2731 break;
2732 case L2CAP_EV_RECV_FBIT:
2733 /* Nothing to process */
2734 break;
2735 default:
2736 break;
2737 }
2738}
2739
2740static void l2cap_tx_state_wait_f(struct l2cap_chan *chan,
2741 struct l2cap_ctrl *control,
2742 struct sk_buff_head *skbs, u8 event)
2743{
2744 BT_DBG("chan %p, control %p, skbs %p, event %d", chan, control, skbs,
2745 event);
2746
2747 switch (event) {
2748 case L2CAP_EV_DATA_REQUEST:
2749 if (chan->tx_send_head == NULL)
2750 chan->tx_send_head = skb_peek(skbs);
2751 /* Queue data, but don't send. */
2752 skb_queue_splice_tail_init(skbs, &chan->tx_q);
2753 break;
2754 case L2CAP_EV_LOCAL_BUSY_DETECTED:
2755 BT_DBG("Enter LOCAL_BUSY");
2756 set_bit(CONN_LOCAL_BUSY, &chan->conn_state);
2757
2758 if (chan->rx_state == L2CAP_RX_STATE_SREJ_SENT) {
2759 /* The SREJ_SENT state must be aborted if we are to
2760 * enter the LOCAL_BUSY state.
2761 */
2762 l2cap_abort_rx_srej_sent(chan);
2763 }
2764
2765 l2cap_send_ack(chan);
2766
2767 break;
2768 case L2CAP_EV_LOCAL_BUSY_CLEAR:
2769 BT_DBG("Exit LOCAL_BUSY");
2770 clear_bit(CONN_LOCAL_BUSY, &chan->conn_state);
2771
2772 if (test_bit(CONN_RNR_SENT, &chan->conn_state)) {
2773 struct l2cap_ctrl local_control;
2774 memset(&local_control, 0, sizeof(local_control));
2775 local_control.sframe = 1;
2776 local_control.super = L2CAP_SUPER_RR;
2777 local_control.poll = 1;
2778 local_control.reqseq = chan->buffer_seq;
2779 l2cap_send_sframe(chan, &local_control);
2780
2781 chan->retry_count = 1;
2782 __set_monitor_timer(chan);
2783 chan->tx_state = L2CAP_TX_STATE_WAIT_F;
2784 }
2785 break;
2786 case L2CAP_EV_RECV_REQSEQ_AND_FBIT:
2787 l2cap_process_reqseq(chan, control->reqseq);
2788
2789 /* Fall through */
2790
2791 case L2CAP_EV_RECV_FBIT:
2792 if (control && control->final) {
2793 __clear_monitor_timer(chan);
2794 if (chan->unacked_frames > 0)
2795 __set_retrans_timer(chan);
2796 chan->retry_count = 0;
2797 chan->tx_state = L2CAP_TX_STATE_XMIT;
2798 BT_DBG("recv fbit tx_state 0x2.2%x", chan->tx_state);
2799 }
2800 break;
2801 case L2CAP_EV_EXPLICIT_POLL:
2802 /* Ignore */
2803 break;
2804 case L2CAP_EV_MONITOR_TO:
2805 if (chan->max_tx == 0 || chan->retry_count < chan->max_tx) {
2806 l2cap_send_rr_or_rnr(chan, 1);
2807 __set_monitor_timer(chan);
2808 chan->retry_count++;
2809 } else {
2810 l2cap_send_disconn_req(chan, ECONNABORTED);
2811 }
2812 break;
2813 default:
2814 break;
2815 }
2816}
2817
2818static void l2cap_tx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
2819 struct sk_buff_head *skbs, u8 event)
2820{
2821 BT_DBG("chan %p, control %p, skbs %p, event %d, state %d",
2822 chan, control, skbs, event, chan->tx_state);
2823
2824 switch (chan->tx_state) {
2825 case L2CAP_TX_STATE_XMIT:
2826 l2cap_tx_state_xmit(chan, control, skbs, event);
2827 break;
2828 case L2CAP_TX_STATE_WAIT_F:
2829 l2cap_tx_state_wait_f(chan, control, skbs, event);
2830 break;
2831 default:
2832 /* Ignore event */
2833 break;
2834 }
2835}
2836
2837static void l2cap_pass_to_tx(struct l2cap_chan *chan,
2838 struct l2cap_ctrl *control)
2839{
2840 BT_DBG("chan %p, control %p", chan, control);
2841 l2cap_tx(chan, control, NULL, L2CAP_EV_RECV_REQSEQ_AND_FBIT);
2842}
2843
2844static void l2cap_pass_to_tx_fbit(struct l2cap_chan *chan,
2845 struct l2cap_ctrl *control)
2846{
2847 BT_DBG("chan %p, control %p", chan, control);
2848 l2cap_tx(chan, control, NULL, L2CAP_EV_RECV_FBIT);
2849}
2850
2851/* Copy frame to all raw sockets on that connection */
2852static void l2cap_raw_recv(struct l2cap_conn *conn, struct sk_buff *skb)
2853{
2854 struct sk_buff *nskb;
2855 struct l2cap_chan *chan;
2856
2857 BT_DBG("conn %p", conn);
2858
2859 mutex_lock(&conn->chan_lock);
2860
2861 list_for_each_entry(chan, &conn->chan_l, list) {
2862 if (chan->chan_type != L2CAP_CHAN_RAW)
2863 continue;
2864
2865 /* Don't send frame to the channel it came from */
2866 if (bt_cb(skb)->l2cap.chan == chan)
2867 continue;
2868
2869 nskb = skb_clone(skb, GFP_KERNEL);
2870 if (!nskb)
2871 continue;
2872 if (chan->ops->recv(chan, nskb))
2873 kfree_skb(nskb);
2874 }
2875
2876 mutex_unlock(&conn->chan_lock);
2877}
2878
2879/* ---- L2CAP signalling commands ---- */
2880static struct sk_buff *l2cap_build_cmd(struct l2cap_conn *conn, u8 code,
2881 u8 ident, u16 dlen, void *data)
2882{
2883 struct sk_buff *skb, **frag;
2884 struct l2cap_cmd_hdr *cmd;
2885 struct l2cap_hdr *lh;
2886 int len, count;
2887
2888 BT_DBG("conn %p, code 0x%2.2x, ident 0x%2.2x, len %u",
2889 conn, code, ident, dlen);
2890
2891 if (conn->mtu < L2CAP_HDR_SIZE + L2CAP_CMD_HDR_SIZE)
2892 return NULL;
2893
2894 len = L2CAP_HDR_SIZE + L2CAP_CMD_HDR_SIZE + dlen;
2895 count = min_t(unsigned int, conn->mtu, len);
2896
2897 skb = bt_skb_alloc(count, GFP_KERNEL);
2898 if (!skb)
2899 return NULL;
2900
2901 lh = (struct l2cap_hdr *) skb_put(skb, L2CAP_HDR_SIZE);
2902 lh->len = cpu_to_le16(L2CAP_CMD_HDR_SIZE + dlen);
2903
2904 if (conn->hcon->type == LE_LINK)
2905 lh->cid = cpu_to_le16(L2CAP_CID_LE_SIGNALING);
2906 else
2907 lh->cid = cpu_to_le16(L2CAP_CID_SIGNALING);
2908
2909 cmd = (struct l2cap_cmd_hdr *) skb_put(skb, L2CAP_CMD_HDR_SIZE);
2910 cmd->code = code;
2911 cmd->ident = ident;
2912 cmd->len = cpu_to_le16(dlen);
2913
2914 if (dlen) {
2915 count -= L2CAP_HDR_SIZE + L2CAP_CMD_HDR_SIZE;
2916 memcpy(skb_put(skb, count), data, count);
2917 data += count;
2918 }
2919
2920 len -= skb->len;
2921
2922 /* Continuation fragments (no L2CAP header) */
2923 frag = &skb_shinfo(skb)->frag_list;
2924 while (len) {
2925 count = min_t(unsigned int, conn->mtu, len);
2926
2927 *frag = bt_skb_alloc(count, GFP_KERNEL);
2928 if (!*frag)
2929 goto fail;
2930
2931 memcpy(skb_put(*frag, count), data, count);
2932
2933 len -= count;
2934 data += count;
2935
2936 frag = &(*frag)->next;
2937 }
2938
2939 return skb;
2940
2941fail:
2942 kfree_skb(skb);
2943 return NULL;
2944}
2945
2946static inline int l2cap_get_conf_opt(void **ptr, int *type, int *olen,
2947 unsigned long *val)
2948{
2949 struct l2cap_conf_opt *opt = *ptr;
2950 int len;
2951
2952 len = L2CAP_CONF_OPT_SIZE + opt->len;
2953 *ptr += len;
2954
2955 *type = opt->type;
2956 *olen = opt->len;
2957
2958 switch (opt->len) {
2959 case 1:
2960 *val = *((u8 *) opt->val);
2961 break;
2962
2963 case 2:
2964 *val = get_unaligned_le16(opt->val);
2965 break;
2966
2967 case 4:
2968 *val = get_unaligned_le32(opt->val);
2969 break;
2970
2971 default:
2972 *val = (unsigned long) opt->val;
2973 break;
2974 }
2975
2976 BT_DBG("type 0x%2.2x len %u val 0x%lx", *type, opt->len, *val);
2977 return len;
2978}
2979
2980static void l2cap_add_conf_opt(void **ptr, u8 type, u8 len, unsigned long val)
2981{
2982 struct l2cap_conf_opt *opt = *ptr;
2983
2984 BT_DBG("type 0x%2.2x len %u val 0x%lx", type, len, val);
2985
2986 opt->type = type;
2987 opt->len = len;
2988
2989 switch (len) {
2990 case 1:
2991 *((u8 *) opt->val) = val;
2992 break;
2993
2994 case 2:
2995 put_unaligned_le16(val, opt->val);
2996 break;
2997
2998 case 4:
2999 put_unaligned_le32(val, opt->val);
3000 break;
3001
3002 default:
3003 memcpy(opt->val, (void *) val, len);
3004 break;
3005 }
3006
3007 *ptr += L2CAP_CONF_OPT_SIZE + len;
3008}
3009
3010static void l2cap_add_opt_efs(void **ptr, struct l2cap_chan *chan)
3011{
3012 struct l2cap_conf_efs efs;
3013
3014 switch (chan->mode) {
3015 case L2CAP_MODE_ERTM:
3016 efs.id = chan->local_id;
3017 efs.stype = chan->local_stype;
3018 efs.msdu = cpu_to_le16(chan->local_msdu);
3019 efs.sdu_itime = cpu_to_le32(chan->local_sdu_itime);
3020 efs.acc_lat = cpu_to_le32(L2CAP_DEFAULT_ACC_LAT);
3021 efs.flush_to = cpu_to_le32(L2CAP_EFS_DEFAULT_FLUSH_TO);
3022 break;
3023
3024 case L2CAP_MODE_STREAMING:
3025 efs.id = 1;
3026 efs.stype = L2CAP_SERV_BESTEFFORT;
3027 efs.msdu = cpu_to_le16(chan->local_msdu);
3028 efs.sdu_itime = cpu_to_le32(chan->local_sdu_itime);
3029 efs.acc_lat = 0;
3030 efs.flush_to = 0;
3031 break;
3032
3033 default:
3034 return;
3035 }
3036
3037 l2cap_add_conf_opt(ptr, L2CAP_CONF_EFS, sizeof(efs),
3038 (unsigned long) &efs);
3039}
3040
3041static void l2cap_ack_timeout(struct work_struct *work)
3042{
3043 struct l2cap_chan *chan = container_of(work, struct l2cap_chan,
3044 ack_timer.work);
3045 u16 frames_to_ack;
3046
3047 BT_DBG("chan %p", chan);
3048
3049 l2cap_chan_lock(chan);
3050
3051 frames_to_ack = __seq_offset(chan, chan->buffer_seq,
3052 chan->last_acked_seq);
3053
3054 if (frames_to_ack)
3055 l2cap_send_rr_or_rnr(chan, 0);
3056
3057 l2cap_chan_unlock(chan);
3058 l2cap_chan_put(chan);
3059}
3060
3061int l2cap_ertm_init(struct l2cap_chan *chan)
3062{
3063 int err;
3064
3065 chan->next_tx_seq = 0;
3066 chan->expected_tx_seq = 0;
3067 chan->expected_ack_seq = 0;
3068 chan->unacked_frames = 0;
3069 chan->buffer_seq = 0;
3070 chan->frames_sent = 0;
3071 chan->last_acked_seq = 0;
3072 chan->sdu = NULL;
3073 chan->sdu_last_frag = NULL;
3074 chan->sdu_len = 0;
3075
3076 skb_queue_head_init(&chan->tx_q);
3077
3078 chan->local_amp_id = AMP_ID_BREDR;
3079 chan->move_id = AMP_ID_BREDR;
3080 chan->move_state = L2CAP_MOVE_STABLE;
3081 chan->move_role = L2CAP_MOVE_ROLE_NONE;
3082
3083 if (chan->mode != L2CAP_MODE_ERTM)
3084 return 0;
3085
3086 chan->rx_state = L2CAP_RX_STATE_RECV;
3087 chan->tx_state = L2CAP_TX_STATE_XMIT;
3088
3089 INIT_DELAYED_WORK(&chan->retrans_timer, l2cap_retrans_timeout);
3090 INIT_DELAYED_WORK(&chan->monitor_timer, l2cap_monitor_timeout);
3091 INIT_DELAYED_WORK(&chan->ack_timer, l2cap_ack_timeout);
3092
3093 skb_queue_head_init(&chan->srej_q);
3094
3095 err = l2cap_seq_list_init(&chan->srej_list, chan->tx_win);
3096 if (err < 0)
3097 return err;
3098
3099 err = l2cap_seq_list_init(&chan->retrans_list, chan->remote_tx_win);
3100 if (err < 0)
3101 l2cap_seq_list_free(&chan->srej_list);
3102
3103 return err;
3104}
3105
3106static inline __u8 l2cap_select_mode(__u8 mode, __u16 remote_feat_mask)
3107{
3108 switch (mode) {
3109 case L2CAP_MODE_STREAMING:
3110 case L2CAP_MODE_ERTM:
3111 if (l2cap_mode_supported(mode, remote_feat_mask))
3112 return mode;
3113 /* fall through */
3114 default:
3115 return L2CAP_MODE_BASIC;
3116 }
3117}
3118
3119static inline bool __l2cap_ews_supported(struct l2cap_conn *conn)
3120{
3121 return ((conn->local_fixed_chan & L2CAP_FC_A2MP) &&
3122 (conn->feat_mask & L2CAP_FEAT_EXT_WINDOW));
3123}
3124
3125static inline bool __l2cap_efs_supported(struct l2cap_conn *conn)
3126{
3127 return ((conn->local_fixed_chan & L2CAP_FC_A2MP) &&
3128 (conn->feat_mask & L2CAP_FEAT_EXT_FLOW));
3129}
3130
3131static void __l2cap_set_ertm_timeouts(struct l2cap_chan *chan,
3132 struct l2cap_conf_rfc *rfc)
3133{
3134 if (chan->local_amp_id != AMP_ID_BREDR && chan->hs_hcon) {
3135 u64 ertm_to = chan->hs_hcon->hdev->amp_be_flush_to;
3136
3137 /* Class 1 devices have must have ERTM timeouts
3138 * exceeding the Link Supervision Timeout. The
3139 * default Link Supervision Timeout for AMP
3140 * controllers is 10 seconds.
3141 *
3142 * Class 1 devices use 0xffffffff for their
3143 * best-effort flush timeout, so the clamping logic
3144 * will result in a timeout that meets the above
3145 * requirement. ERTM timeouts are 16-bit values, so
3146 * the maximum timeout is 65.535 seconds.
3147 */
3148
3149 /* Convert timeout to milliseconds and round */
3150 ertm_to = DIV_ROUND_UP_ULL(ertm_to, 1000);
3151
3152 /* This is the recommended formula for class 2 devices
3153 * that start ERTM timers when packets are sent to the
3154 * controller.
3155 */
3156 ertm_to = 3 * ertm_to + 500;
3157
3158 if (ertm_to > 0xffff)
3159 ertm_to = 0xffff;
3160
3161 rfc->retrans_timeout = cpu_to_le16((u16) ertm_to);
3162 rfc->monitor_timeout = rfc->retrans_timeout;
3163 } else {
3164 rfc->retrans_timeout = cpu_to_le16(L2CAP_DEFAULT_RETRANS_TO);
3165 rfc->monitor_timeout = cpu_to_le16(L2CAP_DEFAULT_MONITOR_TO);
3166 }
3167}
3168
3169static inline void l2cap_txwin_setup(struct l2cap_chan *chan)
3170{
3171 if (chan->tx_win > L2CAP_DEFAULT_TX_WINDOW &&
3172 __l2cap_ews_supported(chan->conn)) {
3173 /* use extended control field */
3174 set_bit(FLAG_EXT_CTRL, &chan->flags);
3175 chan->tx_win_max = L2CAP_DEFAULT_EXT_WINDOW;
3176 } else {
3177 chan->tx_win = min_t(u16, chan->tx_win,
3178 L2CAP_DEFAULT_TX_WINDOW);
3179 chan->tx_win_max = L2CAP_DEFAULT_TX_WINDOW;
3180 }
3181 chan->ack_win = chan->tx_win;
3182}
3183
3184static int l2cap_build_conf_req(struct l2cap_chan *chan, void *data)
3185{
3186 struct l2cap_conf_req *req = data;
3187 struct l2cap_conf_rfc rfc = { .mode = chan->mode };
3188 void *ptr = req->data;
3189 u16 size;
3190
3191 BT_DBG("chan %p", chan);
3192
3193 if (chan->num_conf_req || chan->num_conf_rsp)
3194 goto done;
3195
3196 switch (chan->mode) {
3197 case L2CAP_MODE_STREAMING:
3198 case L2CAP_MODE_ERTM:
3199 if (test_bit(CONF_STATE2_DEVICE, &chan->conf_state))
3200 break;
3201
3202 if (__l2cap_efs_supported(chan->conn))
3203 set_bit(FLAG_EFS_ENABLE, &chan->flags);
3204
3205 /* fall through */
3206 default:
3207 chan->mode = l2cap_select_mode(rfc.mode, chan->conn->feat_mask);
3208 break;
3209 }
3210
3211done:
3212 if (chan->imtu != L2CAP_DEFAULT_MTU)
3213 l2cap_add_conf_opt(&ptr, L2CAP_CONF_MTU, 2, chan->imtu);
3214
3215 switch (chan->mode) {
3216 case L2CAP_MODE_BASIC:
3217 if (disable_ertm)
3218 break;
3219
3220 if (!(chan->conn->feat_mask & L2CAP_FEAT_ERTM) &&
3221 !(chan->conn->feat_mask & L2CAP_FEAT_STREAMING))
3222 break;
3223
3224 rfc.mode = L2CAP_MODE_BASIC;
3225 rfc.txwin_size = 0;
3226 rfc.max_transmit = 0;
3227 rfc.retrans_timeout = 0;
3228 rfc.monitor_timeout = 0;
3229 rfc.max_pdu_size = 0;
3230
3231 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3232 (unsigned long) &rfc);
3233 break;
3234
3235 case L2CAP_MODE_ERTM:
3236 rfc.mode = L2CAP_MODE_ERTM;
3237 rfc.max_transmit = chan->max_tx;
3238
3239 __l2cap_set_ertm_timeouts(chan, &rfc);
3240
3241 size = min_t(u16, L2CAP_DEFAULT_MAX_PDU_SIZE, chan->conn->mtu -
3242 L2CAP_EXT_HDR_SIZE - L2CAP_SDULEN_SIZE -
3243 L2CAP_FCS_SIZE);
3244 rfc.max_pdu_size = cpu_to_le16(size);
3245
3246 l2cap_txwin_setup(chan);
3247
3248 rfc.txwin_size = min_t(u16, chan->tx_win,
3249 L2CAP_DEFAULT_TX_WINDOW);
3250
3251 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3252 (unsigned long) &rfc);
3253
3254 if (test_bit(FLAG_EFS_ENABLE, &chan->flags))
3255 l2cap_add_opt_efs(&ptr, chan);
3256
3257 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
3258 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EWS, 2,
3259 chan->tx_win);
3260
3261 if (chan->conn->feat_mask & L2CAP_FEAT_FCS)
3262 if (chan->fcs == L2CAP_FCS_NONE ||
3263 test_bit(CONF_RECV_NO_FCS, &chan->conf_state)) {
3264 chan->fcs = L2CAP_FCS_NONE;
3265 l2cap_add_conf_opt(&ptr, L2CAP_CONF_FCS, 1,
3266 chan->fcs);
3267 }
3268 break;
3269
3270 case L2CAP_MODE_STREAMING:
3271 l2cap_txwin_setup(chan);
3272 rfc.mode = L2CAP_MODE_STREAMING;
3273 rfc.txwin_size = 0;
3274 rfc.max_transmit = 0;
3275 rfc.retrans_timeout = 0;
3276 rfc.monitor_timeout = 0;
3277
3278 size = min_t(u16, L2CAP_DEFAULT_MAX_PDU_SIZE, chan->conn->mtu -
3279 L2CAP_EXT_HDR_SIZE - L2CAP_SDULEN_SIZE -
3280 L2CAP_FCS_SIZE);
3281 rfc.max_pdu_size = cpu_to_le16(size);
3282
3283 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3284 (unsigned long) &rfc);
3285
3286 if (test_bit(FLAG_EFS_ENABLE, &chan->flags))
3287 l2cap_add_opt_efs(&ptr, chan);
3288
3289 if (chan->conn->feat_mask & L2CAP_FEAT_FCS)
3290 if (chan->fcs == L2CAP_FCS_NONE ||
3291 test_bit(CONF_RECV_NO_FCS, &chan->conf_state)) {
3292 chan->fcs = L2CAP_FCS_NONE;
3293 l2cap_add_conf_opt(&ptr, L2CAP_CONF_FCS, 1,
3294 chan->fcs);
3295 }
3296 break;
3297 }
3298
3299 req->dcid = cpu_to_le16(chan->dcid);
3300 req->flags = cpu_to_le16(0);
3301
3302 return ptr - data;
3303}
3304
3305static int l2cap_parse_conf_req(struct l2cap_chan *chan, void *data)
3306{
3307 struct l2cap_conf_rsp *rsp = data;
3308 void *ptr = rsp->data;
3309 void *req = chan->conf_req;
3310 int len = chan->conf_len;
3311 int type, hint, olen;
3312 unsigned long val;
3313 struct l2cap_conf_rfc rfc = { .mode = L2CAP_MODE_BASIC };
3314 struct l2cap_conf_efs efs;
3315 u8 remote_efs = 0;
3316 u16 mtu = L2CAP_DEFAULT_MTU;
3317 u16 result = L2CAP_CONF_SUCCESS;
3318 u16 size;
3319
3320 BT_DBG("chan %p", chan);
3321
3322 while (len >= L2CAP_CONF_OPT_SIZE) {
3323 len -= l2cap_get_conf_opt(&req, &type, &olen, &val);
3324
3325 hint = type & L2CAP_CONF_HINT;
3326 type &= L2CAP_CONF_MASK;
3327
3328 switch (type) {
3329 case L2CAP_CONF_MTU:
3330 mtu = val;
3331 break;
3332
3333 case L2CAP_CONF_FLUSH_TO:
3334 chan->flush_to = val;
3335 break;
3336
3337 case L2CAP_CONF_QOS:
3338 break;
3339
3340 case L2CAP_CONF_RFC:
3341 if (olen == sizeof(rfc))
3342 memcpy(&rfc, (void *) val, olen);
3343 break;
3344
3345 case L2CAP_CONF_FCS:
3346 if (val == L2CAP_FCS_NONE)
3347 set_bit(CONF_RECV_NO_FCS, &chan->conf_state);
3348 break;
3349
3350 case L2CAP_CONF_EFS:
3351 remote_efs = 1;
3352 if (olen == sizeof(efs))
3353 memcpy(&efs, (void *) val, olen);
3354 break;
3355
3356 case L2CAP_CONF_EWS:
3357 if (!(chan->conn->local_fixed_chan & L2CAP_FC_A2MP))
3358 return -ECONNREFUSED;
3359
3360 set_bit(FLAG_EXT_CTRL, &chan->flags);
3361 set_bit(CONF_EWS_RECV, &chan->conf_state);
3362 chan->tx_win_max = L2CAP_DEFAULT_EXT_WINDOW;
3363 chan->remote_tx_win = val;
3364 break;
3365
3366 default:
3367 if (hint)
3368 break;
3369
3370 result = L2CAP_CONF_UNKNOWN;
3371 *((u8 *) ptr++) = type;
3372 break;
3373 }
3374 }
3375
3376 if (chan->num_conf_rsp || chan->num_conf_req > 1)
3377 goto done;
3378
3379 switch (chan->mode) {
3380 case L2CAP_MODE_STREAMING:
3381 case L2CAP_MODE_ERTM:
3382 if (!test_bit(CONF_STATE2_DEVICE, &chan->conf_state)) {
3383 chan->mode = l2cap_select_mode(rfc.mode,
3384 chan->conn->feat_mask);
3385 break;
3386 }
3387
3388 if (remote_efs) {
3389 if (__l2cap_efs_supported(chan->conn))
3390 set_bit(FLAG_EFS_ENABLE, &chan->flags);
3391 else
3392 return -ECONNREFUSED;
3393 }
3394
3395 if (chan->mode != rfc.mode)
3396 return -ECONNREFUSED;
3397
3398 break;
3399 }
3400
3401done:
3402 if (chan->mode != rfc.mode) {
3403 result = L2CAP_CONF_UNACCEPT;
3404 rfc.mode = chan->mode;
3405
3406 if (chan->num_conf_rsp == 1)
3407 return -ECONNREFUSED;
3408
3409 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3410 (unsigned long) &rfc);
3411 }
3412
3413 if (result == L2CAP_CONF_SUCCESS) {
3414 /* Configure output options and let the other side know
3415 * which ones we don't like. */
3416
3417 if (mtu < L2CAP_DEFAULT_MIN_MTU)
3418 result = L2CAP_CONF_UNACCEPT;
3419 else {
3420 chan->omtu = mtu;
3421 set_bit(CONF_MTU_DONE, &chan->conf_state);
3422 }
3423 l2cap_add_conf_opt(&ptr, L2CAP_CONF_MTU, 2, chan->omtu);
3424
3425 if (remote_efs) {
3426 if (chan->local_stype != L2CAP_SERV_NOTRAFIC &&
3427 efs.stype != L2CAP_SERV_NOTRAFIC &&
3428 efs.stype != chan->local_stype) {
3429
3430 result = L2CAP_CONF_UNACCEPT;
3431
3432 if (chan->num_conf_req >= 1)
3433 return -ECONNREFUSED;
3434
3435 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EFS,
3436 sizeof(efs),
3437 (unsigned long) &efs);
3438 } else {
3439 /* Send PENDING Conf Rsp */
3440 result = L2CAP_CONF_PENDING;
3441 set_bit(CONF_LOC_CONF_PEND, &chan->conf_state);
3442 }
3443 }
3444
3445 switch (rfc.mode) {
3446 case L2CAP_MODE_BASIC:
3447 chan->fcs = L2CAP_FCS_NONE;
3448 set_bit(CONF_MODE_DONE, &chan->conf_state);
3449 break;
3450
3451 case L2CAP_MODE_ERTM:
3452 if (!test_bit(CONF_EWS_RECV, &chan->conf_state))
3453 chan->remote_tx_win = rfc.txwin_size;
3454 else
3455 rfc.txwin_size = L2CAP_DEFAULT_TX_WINDOW;
3456
3457 chan->remote_max_tx = rfc.max_transmit;
3458
3459 size = min_t(u16, le16_to_cpu(rfc.max_pdu_size),
3460 chan->conn->mtu - L2CAP_EXT_HDR_SIZE -
3461 L2CAP_SDULEN_SIZE - L2CAP_FCS_SIZE);
3462 rfc.max_pdu_size = cpu_to_le16(size);
3463 chan->remote_mps = size;
3464
3465 __l2cap_set_ertm_timeouts(chan, &rfc);
3466
3467 set_bit(CONF_MODE_DONE, &chan->conf_state);
3468
3469 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC,
3470 sizeof(rfc), (unsigned long) &rfc);
3471
3472 if (test_bit(FLAG_EFS_ENABLE, &chan->flags)) {
3473 chan->remote_id = efs.id;
3474 chan->remote_stype = efs.stype;
3475 chan->remote_msdu = le16_to_cpu(efs.msdu);
3476 chan->remote_flush_to =
3477 le32_to_cpu(efs.flush_to);
3478 chan->remote_acc_lat =
3479 le32_to_cpu(efs.acc_lat);
3480 chan->remote_sdu_itime =
3481 le32_to_cpu(efs.sdu_itime);
3482 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EFS,
3483 sizeof(efs),
3484 (unsigned long) &efs);
3485 }
3486 break;
3487
3488 case L2CAP_MODE_STREAMING:
3489 size = min_t(u16, le16_to_cpu(rfc.max_pdu_size),
3490 chan->conn->mtu - L2CAP_EXT_HDR_SIZE -
3491 L2CAP_SDULEN_SIZE - L2CAP_FCS_SIZE);
3492 rfc.max_pdu_size = cpu_to_le16(size);
3493 chan->remote_mps = size;
3494
3495 set_bit(CONF_MODE_DONE, &chan->conf_state);
3496
3497 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3498 (unsigned long) &rfc);
3499
3500 break;
3501
3502 default:
3503 result = L2CAP_CONF_UNACCEPT;
3504
3505 memset(&rfc, 0, sizeof(rfc));
3506 rfc.mode = chan->mode;
3507 }
3508
3509 if (result == L2CAP_CONF_SUCCESS)
3510 set_bit(CONF_OUTPUT_DONE, &chan->conf_state);
3511 }
3512 rsp->scid = cpu_to_le16(chan->dcid);
3513 rsp->result = cpu_to_le16(result);
3514 rsp->flags = cpu_to_le16(0);
3515
3516 return ptr - data;
3517}
3518
3519static int l2cap_parse_conf_rsp(struct l2cap_chan *chan, void *rsp, int len,
3520 void *data, u16 *result)
3521{
3522 struct l2cap_conf_req *req = data;
3523 void *ptr = req->data;
3524 int type, olen;
3525 unsigned long val;
3526 struct l2cap_conf_rfc rfc = { .mode = L2CAP_MODE_BASIC };
3527 struct l2cap_conf_efs efs;
3528
3529 BT_DBG("chan %p, rsp %p, len %d, req %p", chan, rsp, len, data);
3530
3531 while (len >= L2CAP_CONF_OPT_SIZE) {
3532 len -= l2cap_get_conf_opt(&rsp, &type, &olen, &val);
3533
3534 switch (type) {
3535 case L2CAP_CONF_MTU:
3536 if (val < L2CAP_DEFAULT_MIN_MTU) {
3537 *result = L2CAP_CONF_UNACCEPT;
3538 chan->imtu = L2CAP_DEFAULT_MIN_MTU;
3539 } else
3540 chan->imtu = val;
3541 l2cap_add_conf_opt(&ptr, L2CAP_CONF_MTU, 2, chan->imtu);
3542 break;
3543
3544 case L2CAP_CONF_FLUSH_TO:
3545 chan->flush_to = val;
3546 l2cap_add_conf_opt(&ptr, L2CAP_CONF_FLUSH_TO,
3547 2, chan->flush_to);
3548 break;
3549
3550 case L2CAP_CONF_RFC:
3551 if (olen == sizeof(rfc))
3552 memcpy(&rfc, (void *)val, olen);
3553
3554 if (test_bit(CONF_STATE2_DEVICE, &chan->conf_state) &&
3555 rfc.mode != chan->mode)
3556 return -ECONNREFUSED;
3557
3558 chan->fcs = 0;
3559
3560 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC,
3561 sizeof(rfc), (unsigned long) &rfc);
3562 break;
3563
3564 case L2CAP_CONF_EWS:
3565 chan->ack_win = min_t(u16, val, chan->ack_win);
3566 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EWS, 2,
3567 chan->tx_win);
3568 break;
3569
3570 case L2CAP_CONF_EFS:
3571 if (olen == sizeof(efs))
3572 memcpy(&efs, (void *)val, olen);
3573
3574 if (chan->local_stype != L2CAP_SERV_NOTRAFIC &&
3575 efs.stype != L2CAP_SERV_NOTRAFIC &&
3576 efs.stype != chan->local_stype)
3577 return -ECONNREFUSED;
3578
3579 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EFS, sizeof(efs),
3580 (unsigned long) &efs);
3581 break;
3582
3583 case L2CAP_CONF_FCS:
3584 if (*result == L2CAP_CONF_PENDING)
3585 if (val == L2CAP_FCS_NONE)
3586 set_bit(CONF_RECV_NO_FCS,
3587 &chan->conf_state);
3588 break;
3589 }
3590 }
3591
3592 if (chan->mode == L2CAP_MODE_BASIC && chan->mode != rfc.mode)
3593 return -ECONNREFUSED;
3594
3595 chan->mode = rfc.mode;
3596
3597 if (*result == L2CAP_CONF_SUCCESS || *result == L2CAP_CONF_PENDING) {
3598 switch (rfc.mode) {
3599 case L2CAP_MODE_ERTM:
3600 chan->retrans_timeout = le16_to_cpu(rfc.retrans_timeout);
3601 chan->monitor_timeout = le16_to_cpu(rfc.monitor_timeout);
3602 chan->mps = le16_to_cpu(rfc.max_pdu_size);
3603 if (!test_bit(FLAG_EXT_CTRL, &chan->flags))
3604 chan->ack_win = min_t(u16, chan->ack_win,
3605 rfc.txwin_size);
3606
3607 if (test_bit(FLAG_EFS_ENABLE, &chan->flags)) {
3608 chan->local_msdu = le16_to_cpu(efs.msdu);
3609 chan->local_sdu_itime =
3610 le32_to_cpu(efs.sdu_itime);
3611 chan->local_acc_lat = le32_to_cpu(efs.acc_lat);
3612 chan->local_flush_to =
3613 le32_to_cpu(efs.flush_to);
3614 }
3615 break;
3616
3617 case L2CAP_MODE_STREAMING:
3618 chan->mps = le16_to_cpu(rfc.max_pdu_size);
3619 }
3620 }
3621
3622 req->dcid = cpu_to_le16(chan->dcid);
3623 req->flags = cpu_to_le16(0);
3624
3625 return ptr - data;
3626}
3627
3628static int l2cap_build_conf_rsp(struct l2cap_chan *chan, void *data,
3629 u16 result, u16 flags)
3630{
3631 struct l2cap_conf_rsp *rsp = data;
3632 void *ptr = rsp->data;
3633
3634 BT_DBG("chan %p", chan);
3635
3636 rsp->scid = cpu_to_le16(chan->dcid);
3637 rsp->result = cpu_to_le16(result);
3638 rsp->flags = cpu_to_le16(flags);
3639
3640 return ptr - data;
3641}
3642
3643void __l2cap_le_connect_rsp_defer(struct l2cap_chan *chan)
3644{
3645 struct l2cap_le_conn_rsp rsp;
3646 struct l2cap_conn *conn = chan->conn;
3647
3648 BT_DBG("chan %p", chan);
3649
3650 rsp.dcid = cpu_to_le16(chan->scid);
3651 rsp.mtu = cpu_to_le16(chan->imtu);
3652 rsp.mps = cpu_to_le16(chan->mps);
3653 rsp.credits = cpu_to_le16(chan->rx_credits);
3654 rsp.result = cpu_to_le16(L2CAP_CR_SUCCESS);
3655
3656 l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CONN_RSP, sizeof(rsp),
3657 &rsp);
3658}
3659
3660void __l2cap_connect_rsp_defer(struct l2cap_chan *chan)
3661{
3662 struct l2cap_conn_rsp rsp;
3663 struct l2cap_conn *conn = chan->conn;
3664 u8 buf[128];
3665 u8 rsp_code;
3666
3667 rsp.scid = cpu_to_le16(chan->dcid);
3668 rsp.dcid = cpu_to_le16(chan->scid);
3669 rsp.result = cpu_to_le16(L2CAP_CR_SUCCESS);
3670 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
3671
3672 if (chan->hs_hcon)
3673 rsp_code = L2CAP_CREATE_CHAN_RSP;
3674 else
3675 rsp_code = L2CAP_CONN_RSP;
3676
3677 BT_DBG("chan %p rsp_code %u", chan, rsp_code);
3678
3679 l2cap_send_cmd(conn, chan->ident, rsp_code, sizeof(rsp), &rsp);
3680
3681 if (test_and_set_bit(CONF_REQ_SENT, &chan->conf_state))
3682 return;
3683
3684 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
3685 l2cap_build_conf_req(chan, buf), buf);
3686 chan->num_conf_req++;
3687}
3688
3689static void l2cap_conf_rfc_get(struct l2cap_chan *chan, void *rsp, int len)
3690{
3691 int type, olen;
3692 unsigned long val;
3693 /* Use sane default values in case a misbehaving remote device
3694 * did not send an RFC or extended window size option.
3695 */
3696 u16 txwin_ext = chan->ack_win;
3697 struct l2cap_conf_rfc rfc = {
3698 .mode = chan->mode,
3699 .retrans_timeout = cpu_to_le16(L2CAP_DEFAULT_RETRANS_TO),
3700 .monitor_timeout = cpu_to_le16(L2CAP_DEFAULT_MONITOR_TO),
3701 .max_pdu_size = cpu_to_le16(chan->imtu),
3702 .txwin_size = min_t(u16, chan->ack_win, L2CAP_DEFAULT_TX_WINDOW),
3703 };
3704
3705 BT_DBG("chan %p, rsp %p, len %d", chan, rsp, len);
3706
3707 if ((chan->mode != L2CAP_MODE_ERTM) && (chan->mode != L2CAP_MODE_STREAMING))
3708 return;
3709
3710 while (len >= L2CAP_CONF_OPT_SIZE) {
3711 len -= l2cap_get_conf_opt(&rsp, &type, &olen, &val);
3712
3713 switch (type) {
3714 case L2CAP_CONF_RFC:
3715 if (olen == sizeof(rfc))
3716 memcpy(&rfc, (void *)val, olen);
3717 break;
3718 case L2CAP_CONF_EWS:
3719 txwin_ext = val;
3720 break;
3721 }
3722 }
3723
3724 switch (rfc.mode) {
3725 case L2CAP_MODE_ERTM:
3726 chan->retrans_timeout = le16_to_cpu(rfc.retrans_timeout);
3727 chan->monitor_timeout = le16_to_cpu(rfc.monitor_timeout);
3728 chan->mps = le16_to_cpu(rfc.max_pdu_size);
3729 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
3730 chan->ack_win = min_t(u16, chan->ack_win, txwin_ext);
3731 else
3732 chan->ack_win = min_t(u16, chan->ack_win,
3733 rfc.txwin_size);
3734 break;
3735 case L2CAP_MODE_STREAMING:
3736 chan->mps = le16_to_cpu(rfc.max_pdu_size);
3737 }
3738}
3739
3740static inline int l2cap_command_rej(struct l2cap_conn *conn,
3741 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
3742 u8 *data)
3743{
3744 struct l2cap_cmd_rej_unk *rej = (struct l2cap_cmd_rej_unk *) data;
3745
3746 if (cmd_len < sizeof(*rej))
3747 return -EPROTO;
3748
3749 if (rej->reason != L2CAP_REJ_NOT_UNDERSTOOD)
3750 return 0;
3751
3752 if ((conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT) &&
3753 cmd->ident == conn->info_ident) {
3754 cancel_delayed_work(&conn->info_timer);
3755
3756 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
3757 conn->info_ident = 0;
3758
3759 l2cap_conn_start(conn);
3760 }
3761
3762 return 0;
3763}
3764
3765static struct l2cap_chan *l2cap_connect(struct l2cap_conn *conn,
3766 struct l2cap_cmd_hdr *cmd,
3767 u8 *data, u8 rsp_code, u8 amp_id)
3768{
3769 struct l2cap_conn_req *req = (struct l2cap_conn_req *) data;
3770 struct l2cap_conn_rsp rsp;
3771 struct l2cap_chan *chan = NULL, *pchan;
3772 int result, status = L2CAP_CS_NO_INFO;
3773
3774 u16 dcid = 0, scid = __le16_to_cpu(req->scid);
3775 __le16 psm = req->psm;
3776
3777 BT_DBG("psm 0x%2.2x scid 0x%4.4x", __le16_to_cpu(psm), scid);
3778
3779 /* Check if we have socket listening on psm */
3780 pchan = l2cap_global_chan_by_psm(BT_LISTEN, psm, &conn->hcon->src,
3781 &conn->hcon->dst, ACL_LINK);
3782 if (!pchan) {
3783 result = L2CAP_CR_BAD_PSM;
3784 goto sendresp;
3785 }
3786
3787 mutex_lock(&conn->chan_lock);
3788 l2cap_chan_lock(pchan);
3789
3790 /* Check if the ACL is secure enough (if not SDP) */
3791 if (psm != cpu_to_le16(L2CAP_PSM_SDP) &&
3792 !hci_conn_check_link_mode(conn->hcon)) {
3793 conn->disc_reason = HCI_ERROR_AUTH_FAILURE;
3794 result = L2CAP_CR_SEC_BLOCK;
3795 goto response;
3796 }
3797
3798 result = L2CAP_CR_NO_MEM;
3799
3800 /* Check if we already have channel with that dcid */
3801 if (__l2cap_get_chan_by_dcid(conn, scid))
3802 goto response;
3803
3804 chan = pchan->ops->new_connection(pchan);
3805 if (!chan)
3806 goto response;
3807
3808 /* For certain devices (ex: HID mouse), support for authentication,
3809 * pairing and bonding is optional. For such devices, inorder to avoid
3810 * the ACL alive for too long after L2CAP disconnection, reset the ACL
3811 * disc_timeout back to HCI_DISCONN_TIMEOUT during L2CAP connect.
3812 */
3813 conn->hcon->disc_timeout = HCI_DISCONN_TIMEOUT;
3814
3815 bacpy(&chan->src, &conn->hcon->src);
3816 bacpy(&chan->dst, &conn->hcon->dst);
3817 chan->src_type = bdaddr_src_type(conn->hcon);
3818 chan->dst_type = bdaddr_dst_type(conn->hcon);
3819 chan->psm = psm;
3820 chan->dcid = scid;
3821 chan->local_amp_id = amp_id;
3822
3823 __l2cap_chan_add(conn, chan);
3824
3825 dcid = chan->scid;
3826
3827 __set_chan_timer(chan, chan->ops->get_sndtimeo(chan));
3828
3829 chan->ident = cmd->ident;
3830
3831 if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE) {
3832 if (l2cap_chan_check_security(chan, false)) {
3833 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) {
3834 l2cap_state_change(chan, BT_CONNECT2);
3835 result = L2CAP_CR_PEND;
3836 status = L2CAP_CS_AUTHOR_PEND;
3837 chan->ops->defer(chan);
3838 } else {
3839 /* Force pending result for AMP controllers.
3840 * The connection will succeed after the
3841 * physical link is up.
3842 */
3843 if (amp_id == AMP_ID_BREDR) {
3844 l2cap_state_change(chan, BT_CONFIG);
3845 result = L2CAP_CR_SUCCESS;
3846 } else {
3847 l2cap_state_change(chan, BT_CONNECT2);
3848 result = L2CAP_CR_PEND;
3849 }
3850 status = L2CAP_CS_NO_INFO;
3851 }
3852 } else {
3853 l2cap_state_change(chan, BT_CONNECT2);
3854 result = L2CAP_CR_PEND;
3855 status = L2CAP_CS_AUTHEN_PEND;
3856 }
3857 } else {
3858 l2cap_state_change(chan, BT_CONNECT2);
3859 result = L2CAP_CR_PEND;
3860 status = L2CAP_CS_NO_INFO;
3861 }
3862
3863response:
3864 l2cap_chan_unlock(pchan);
3865 mutex_unlock(&conn->chan_lock);
3866 l2cap_chan_put(pchan);
3867
3868sendresp:
3869 rsp.scid = cpu_to_le16(scid);
3870 rsp.dcid = cpu_to_le16(dcid);
3871 rsp.result = cpu_to_le16(result);
3872 rsp.status = cpu_to_le16(status);
3873 l2cap_send_cmd(conn, cmd->ident, rsp_code, sizeof(rsp), &rsp);
3874
3875 if (result == L2CAP_CR_PEND && status == L2CAP_CS_NO_INFO) {
3876 struct l2cap_info_req info;
3877 info.type = cpu_to_le16(L2CAP_IT_FEAT_MASK);
3878
3879 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_SENT;
3880 conn->info_ident = l2cap_get_ident(conn);
3881
3882 schedule_delayed_work(&conn->info_timer, L2CAP_INFO_TIMEOUT);
3883
3884 l2cap_send_cmd(conn, conn->info_ident, L2CAP_INFO_REQ,
3885 sizeof(info), &info);
3886 }
3887
3888 if (chan && !test_bit(CONF_REQ_SENT, &chan->conf_state) &&
3889 result == L2CAP_CR_SUCCESS) {
3890 u8 buf[128];
3891 set_bit(CONF_REQ_SENT, &chan->conf_state);
3892 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
3893 l2cap_build_conf_req(chan, buf), buf);
3894 chan->num_conf_req++;
3895 }
3896
3897 return chan;
3898}
3899
3900static int l2cap_connect_req(struct l2cap_conn *conn,
3901 struct l2cap_cmd_hdr *cmd, u16 cmd_len, u8 *data)
3902{
3903 struct hci_dev *hdev = conn->hcon->hdev;
3904 struct hci_conn *hcon = conn->hcon;
3905
3906 if (cmd_len < sizeof(struct l2cap_conn_req))
3907 return -EPROTO;
3908
3909 hci_dev_lock(hdev);
3910 if (hci_dev_test_flag(hdev, HCI_MGMT) &&
3911 !test_and_set_bit(HCI_CONN_MGMT_CONNECTED, &hcon->flags))
3912 mgmt_device_connected(hdev, hcon, 0, NULL, 0);
3913 hci_dev_unlock(hdev);
3914
3915 l2cap_connect(conn, cmd, data, L2CAP_CONN_RSP, 0);
3916 return 0;
3917}
3918
3919static int l2cap_connect_create_rsp(struct l2cap_conn *conn,
3920 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
3921 u8 *data)
3922{
3923 struct l2cap_conn_rsp *rsp = (struct l2cap_conn_rsp *) data;
3924 u16 scid, dcid, result, status;
3925 struct l2cap_chan *chan;
3926 u8 req[128];
3927 int err;
3928
3929 if (cmd_len < sizeof(*rsp))
3930 return -EPROTO;
3931
3932 scid = __le16_to_cpu(rsp->scid);
3933 dcid = __le16_to_cpu(rsp->dcid);
3934 result = __le16_to_cpu(rsp->result);
3935 status = __le16_to_cpu(rsp->status);
3936
3937 BT_DBG("dcid 0x%4.4x scid 0x%4.4x result 0x%2.2x status 0x%2.2x",
3938 dcid, scid, result, status);
3939
3940 mutex_lock(&conn->chan_lock);
3941
3942 if (scid) {
3943 chan = __l2cap_get_chan_by_scid(conn, scid);
3944 if (!chan) {
3945 err = -EBADSLT;
3946 goto unlock;
3947 }
3948 } else {
3949 chan = __l2cap_get_chan_by_ident(conn, cmd->ident);
3950 if (!chan) {
3951 err = -EBADSLT;
3952 goto unlock;
3953 }
3954 }
3955
3956 err = 0;
3957
3958 l2cap_chan_lock(chan);
3959
3960 switch (result) {
3961 case L2CAP_CR_SUCCESS:
3962 l2cap_state_change(chan, BT_CONFIG);
3963 chan->ident = 0;
3964 chan->dcid = dcid;
3965 clear_bit(CONF_CONNECT_PEND, &chan->conf_state);
3966
3967 if (test_and_set_bit(CONF_REQ_SENT, &chan->conf_state))
3968 break;
3969
3970 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
3971 l2cap_build_conf_req(chan, req), req);
3972 chan->num_conf_req++;
3973 break;
3974
3975 case L2CAP_CR_PEND:
3976 set_bit(CONF_CONNECT_PEND, &chan->conf_state);
3977 break;
3978
3979 default:
3980 l2cap_chan_del(chan, ECONNREFUSED);
3981 break;
3982 }
3983
3984 l2cap_chan_unlock(chan);
3985
3986unlock:
3987 mutex_unlock(&conn->chan_lock);
3988
3989 return err;
3990}
3991
3992static inline void set_default_fcs(struct l2cap_chan *chan)
3993{
3994 /* FCS is enabled only in ERTM or streaming mode, if one or both
3995 * sides request it.
3996 */
3997 if (chan->mode != L2CAP_MODE_ERTM && chan->mode != L2CAP_MODE_STREAMING)
3998 chan->fcs = L2CAP_FCS_NONE;
3999 else if (!test_bit(CONF_RECV_NO_FCS, &chan->conf_state))
4000 chan->fcs = L2CAP_FCS_CRC16;
4001}
4002
4003static void l2cap_send_efs_conf_rsp(struct l2cap_chan *chan, void *data,
4004 u8 ident, u16 flags)
4005{
4006 struct l2cap_conn *conn = chan->conn;
4007
4008 BT_DBG("conn %p chan %p ident %d flags 0x%4.4x", conn, chan, ident,
4009 flags);
4010
4011 clear_bit(CONF_LOC_CONF_PEND, &chan->conf_state);
4012 set_bit(CONF_OUTPUT_DONE, &chan->conf_state);
4013
4014 l2cap_send_cmd(conn, ident, L2CAP_CONF_RSP,
4015 l2cap_build_conf_rsp(chan, data,
4016 L2CAP_CONF_SUCCESS, flags), data);
4017}
4018
4019static void cmd_reject_invalid_cid(struct l2cap_conn *conn, u8 ident,
4020 u16 scid, u16 dcid)
4021{
4022 struct l2cap_cmd_rej_cid rej;
4023
4024 rej.reason = cpu_to_le16(L2CAP_REJ_INVALID_CID);
4025 rej.scid = __cpu_to_le16(scid);
4026 rej.dcid = __cpu_to_le16(dcid);
4027
4028 l2cap_send_cmd(conn, ident, L2CAP_COMMAND_REJ, sizeof(rej), &rej);
4029}
4030
4031static inline int l2cap_config_req(struct l2cap_conn *conn,
4032 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4033 u8 *data)
4034{
4035 struct l2cap_conf_req *req = (struct l2cap_conf_req *) data;
4036 u16 dcid, flags;
4037 u8 rsp[64];
4038 struct l2cap_chan *chan;
4039 int len, err = 0;
4040
4041 if (cmd_len < sizeof(*req))
4042 return -EPROTO;
4043
4044 dcid = __le16_to_cpu(req->dcid);
4045 flags = __le16_to_cpu(req->flags);
4046
4047 BT_DBG("dcid 0x%4.4x flags 0x%2.2x", dcid, flags);
4048
4049 chan = l2cap_get_chan_by_scid(conn, dcid);
4050 if (!chan) {
4051 cmd_reject_invalid_cid(conn, cmd->ident, dcid, 0);
4052 return 0;
4053 }
4054
4055 if (chan->state != BT_CONFIG && chan->state != BT_CONNECT2) {
4056 cmd_reject_invalid_cid(conn, cmd->ident, chan->scid,
4057 chan->dcid);
4058 goto unlock;
4059 }
4060
4061 /* Reject if config buffer is too small. */
4062 len = cmd_len - sizeof(*req);
4063 if (chan->conf_len + len > sizeof(chan->conf_req)) {
4064 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP,
4065 l2cap_build_conf_rsp(chan, rsp,
4066 L2CAP_CONF_REJECT, flags), rsp);
4067 goto unlock;
4068 }
4069
4070 /* Store config. */
4071 memcpy(chan->conf_req + chan->conf_len, req->data, len);
4072 chan->conf_len += len;
4073
4074 if (flags & L2CAP_CONF_FLAG_CONTINUATION) {
4075 /* Incomplete config. Send empty response. */
4076 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP,
4077 l2cap_build_conf_rsp(chan, rsp,
4078 L2CAP_CONF_SUCCESS, flags), rsp);
4079 goto unlock;
4080 }
4081
4082 /* Complete config. */
4083 len = l2cap_parse_conf_req(chan, rsp);
4084 if (len < 0) {
4085 l2cap_send_disconn_req(chan, ECONNRESET);
4086 goto unlock;
4087 }
4088
4089 chan->ident = cmd->ident;
4090 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP, len, rsp);
4091 chan->num_conf_rsp++;
4092
4093 /* Reset config buffer. */
4094 chan->conf_len = 0;
4095
4096 if (!test_bit(CONF_OUTPUT_DONE, &chan->conf_state))
4097 goto unlock;
4098
4099 if (test_bit(CONF_INPUT_DONE, &chan->conf_state)) {
4100 set_default_fcs(chan);
4101
4102 if (chan->mode == L2CAP_MODE_ERTM ||
4103 chan->mode == L2CAP_MODE_STREAMING)
4104 err = l2cap_ertm_init(chan);
4105
4106 if (err < 0)
4107 l2cap_send_disconn_req(chan, -err);
4108 else
4109 l2cap_chan_ready(chan);
4110
4111 goto unlock;
4112 }
4113
4114 if (!test_and_set_bit(CONF_REQ_SENT, &chan->conf_state)) {
4115 u8 buf[64];
4116 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
4117 l2cap_build_conf_req(chan, buf), buf);
4118 chan->num_conf_req++;
4119 }
4120
4121 /* Got Conf Rsp PENDING from remote side and assume we sent
4122 Conf Rsp PENDING in the code above */
4123 if (test_bit(CONF_REM_CONF_PEND, &chan->conf_state) &&
4124 test_bit(CONF_LOC_CONF_PEND, &chan->conf_state)) {
4125
4126 /* check compatibility */
4127
4128 /* Send rsp for BR/EDR channel */
4129 if (!chan->hs_hcon)
4130 l2cap_send_efs_conf_rsp(chan, rsp, cmd->ident, flags);
4131 else
4132 chan->ident = cmd->ident;
4133 }
4134
4135unlock:
4136 l2cap_chan_unlock(chan);
4137 return err;
4138}
4139
4140static inline int l2cap_config_rsp(struct l2cap_conn *conn,
4141 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4142 u8 *data)
4143{
4144 struct l2cap_conf_rsp *rsp = (struct l2cap_conf_rsp *)data;
4145 u16 scid, flags, result;
4146 struct l2cap_chan *chan;
4147 int len = cmd_len - sizeof(*rsp);
4148 int err = 0;
4149
4150 if (cmd_len < sizeof(*rsp))
4151 return -EPROTO;
4152
4153 scid = __le16_to_cpu(rsp->scid);
4154 flags = __le16_to_cpu(rsp->flags);
4155 result = __le16_to_cpu(rsp->result);
4156
4157 BT_DBG("scid 0x%4.4x flags 0x%2.2x result 0x%2.2x len %d", scid, flags,
4158 result, len);
4159
4160 chan = l2cap_get_chan_by_scid(conn, scid);
4161 if (!chan)
4162 return 0;
4163
4164 switch (result) {
4165 case L2CAP_CONF_SUCCESS:
4166 l2cap_conf_rfc_get(chan, rsp->data, len);
4167 clear_bit(CONF_REM_CONF_PEND, &chan->conf_state);
4168 break;
4169
4170 case L2CAP_CONF_PENDING:
4171 set_bit(CONF_REM_CONF_PEND, &chan->conf_state);
4172
4173 if (test_bit(CONF_LOC_CONF_PEND, &chan->conf_state)) {
4174 char buf[64];
4175
4176 len = l2cap_parse_conf_rsp(chan, rsp->data, len,
4177 buf, &result);
4178 if (len < 0) {
4179 l2cap_send_disconn_req(chan, ECONNRESET);
4180 goto done;
4181 }
4182
4183 if (!chan->hs_hcon) {
4184 l2cap_send_efs_conf_rsp(chan, buf, cmd->ident,
4185 0);
4186 } else {
4187 if (l2cap_check_efs(chan)) {
4188 amp_create_logical_link(chan);
4189 chan->ident = cmd->ident;
4190 }
4191 }
4192 }
4193 goto done;
4194
4195 case L2CAP_CONF_UNACCEPT:
4196 if (chan->num_conf_rsp <= L2CAP_CONF_MAX_CONF_RSP) {
4197 char req[64];
4198
4199 if (len > sizeof(req) - sizeof(struct l2cap_conf_req)) {
4200 l2cap_send_disconn_req(chan, ECONNRESET);
4201 goto done;
4202 }
4203
4204 /* throw out any old stored conf requests */
4205 result = L2CAP_CONF_SUCCESS;
4206 len = l2cap_parse_conf_rsp(chan, rsp->data, len,
4207 req, &result);
4208 if (len < 0) {
4209 l2cap_send_disconn_req(chan, ECONNRESET);
4210 goto done;
4211 }
4212
4213 l2cap_send_cmd(conn, l2cap_get_ident(conn),
4214 L2CAP_CONF_REQ, len, req);
4215 chan->num_conf_req++;
4216 if (result != L2CAP_CONF_SUCCESS)
4217 goto done;
4218 break;
4219 }
4220
4221 default:
4222 l2cap_chan_set_err(chan, ECONNRESET);
4223
4224 __set_chan_timer(chan, L2CAP_DISC_REJ_TIMEOUT);
4225 l2cap_send_disconn_req(chan, ECONNRESET);
4226 goto done;
4227 }
4228
4229 if (flags & L2CAP_CONF_FLAG_CONTINUATION)
4230 goto done;
4231
4232 set_bit(CONF_INPUT_DONE, &chan->conf_state);
4233
4234 if (test_bit(CONF_OUTPUT_DONE, &chan->conf_state)) {
4235 set_default_fcs(chan);
4236
4237 if (chan->mode == L2CAP_MODE_ERTM ||
4238 chan->mode == L2CAP_MODE_STREAMING)
4239 err = l2cap_ertm_init(chan);
4240
4241 if (err < 0)
4242 l2cap_send_disconn_req(chan, -err);
4243 else
4244 l2cap_chan_ready(chan);
4245 }
4246
4247done:
4248 l2cap_chan_unlock(chan);
4249 return err;
4250}
4251
4252static inline int l2cap_disconnect_req(struct l2cap_conn *conn,
4253 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4254 u8 *data)
4255{
4256 struct l2cap_disconn_req *req = (struct l2cap_disconn_req *) data;
4257 struct l2cap_disconn_rsp rsp;
4258 u16 dcid, scid;
4259 struct l2cap_chan *chan;
4260
4261 if (cmd_len != sizeof(*req))
4262 return -EPROTO;
4263
4264 scid = __le16_to_cpu(req->scid);
4265 dcid = __le16_to_cpu(req->dcid);
4266
4267 BT_DBG("scid 0x%4.4x dcid 0x%4.4x", scid, dcid);
4268
4269 mutex_lock(&conn->chan_lock);
4270
4271 chan = __l2cap_get_chan_by_scid(conn, dcid);
4272 if (!chan) {
4273 mutex_unlock(&conn->chan_lock);
4274 cmd_reject_invalid_cid(conn, cmd->ident, dcid, scid);
4275 return 0;
4276 }
4277
4278 l2cap_chan_lock(chan);
4279
4280 rsp.dcid = cpu_to_le16(chan->scid);
4281 rsp.scid = cpu_to_le16(chan->dcid);
4282 l2cap_send_cmd(conn, cmd->ident, L2CAP_DISCONN_RSP, sizeof(rsp), &rsp);
4283
4284 chan->ops->set_shutdown(chan);
4285
4286 l2cap_chan_hold(chan);
4287 l2cap_chan_del(chan, ECONNRESET);
4288
4289 l2cap_chan_unlock(chan);
4290
4291 chan->ops->close(chan);
4292 l2cap_chan_put(chan);
4293
4294 mutex_unlock(&conn->chan_lock);
4295
4296 return 0;
4297}
4298
4299static inline int l2cap_disconnect_rsp(struct l2cap_conn *conn,
4300 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4301 u8 *data)
4302{
4303 struct l2cap_disconn_rsp *rsp = (struct l2cap_disconn_rsp *) data;
4304 u16 dcid, scid;
4305 struct l2cap_chan *chan;
4306
4307 if (cmd_len != sizeof(*rsp))
4308 return -EPROTO;
4309
4310 scid = __le16_to_cpu(rsp->scid);
4311 dcid = __le16_to_cpu(rsp->dcid);
4312
4313 BT_DBG("dcid 0x%4.4x scid 0x%4.4x", dcid, scid);
4314
4315 mutex_lock(&conn->chan_lock);
4316
4317 chan = __l2cap_get_chan_by_scid(conn, scid);
4318 if (!chan) {
4319 mutex_unlock(&conn->chan_lock);
4320 return 0;
4321 }
4322
4323 l2cap_chan_lock(chan);
4324
4325 l2cap_chan_hold(chan);
4326 l2cap_chan_del(chan, 0);
4327
4328 l2cap_chan_unlock(chan);
4329
4330 chan->ops->close(chan);
4331 l2cap_chan_put(chan);
4332
4333 mutex_unlock(&conn->chan_lock);
4334
4335 return 0;
4336}
4337
4338static inline int l2cap_information_req(struct l2cap_conn *conn,
4339 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4340 u8 *data)
4341{
4342 struct l2cap_info_req *req = (struct l2cap_info_req *) data;
4343 u16 type;
4344
4345 if (cmd_len != sizeof(*req))
4346 return -EPROTO;
4347
4348 type = __le16_to_cpu(req->type);
4349
4350 BT_DBG("type 0x%4.4x", type);
4351
4352 if (type == L2CAP_IT_FEAT_MASK) {
4353 u8 buf[8];
4354 u32 feat_mask = l2cap_feat_mask;
4355 struct l2cap_info_rsp *rsp = (struct l2cap_info_rsp *) buf;
4356 rsp->type = cpu_to_le16(L2CAP_IT_FEAT_MASK);
4357 rsp->result = cpu_to_le16(L2CAP_IR_SUCCESS);
4358 if (!disable_ertm)
4359 feat_mask |= L2CAP_FEAT_ERTM | L2CAP_FEAT_STREAMING
4360 | L2CAP_FEAT_FCS;
4361 if (conn->local_fixed_chan & L2CAP_FC_A2MP)
4362 feat_mask |= L2CAP_FEAT_EXT_FLOW
4363 | L2CAP_FEAT_EXT_WINDOW;
4364
4365 put_unaligned_le32(feat_mask, rsp->data);
4366 l2cap_send_cmd(conn, cmd->ident, L2CAP_INFO_RSP, sizeof(buf),
4367 buf);
4368 } else if (type == L2CAP_IT_FIXED_CHAN) {
4369 u8 buf[12];
4370 struct l2cap_info_rsp *rsp = (struct l2cap_info_rsp *) buf;
4371
4372 rsp->type = cpu_to_le16(L2CAP_IT_FIXED_CHAN);
4373 rsp->result = cpu_to_le16(L2CAP_IR_SUCCESS);
4374 rsp->data[0] = conn->local_fixed_chan;
4375 memset(rsp->data + 1, 0, 7);
4376 l2cap_send_cmd(conn, cmd->ident, L2CAP_INFO_RSP, sizeof(buf),
4377 buf);
4378 } else {
4379 struct l2cap_info_rsp rsp;
4380 rsp.type = cpu_to_le16(type);
4381 rsp.result = cpu_to_le16(L2CAP_IR_NOTSUPP);
4382 l2cap_send_cmd(conn, cmd->ident, L2CAP_INFO_RSP, sizeof(rsp),
4383 &rsp);
4384 }
4385
4386 return 0;
4387}
4388
4389static inline int l2cap_information_rsp(struct l2cap_conn *conn,
4390 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4391 u8 *data)
4392{
4393 struct l2cap_info_rsp *rsp = (struct l2cap_info_rsp *) data;
4394 u16 type, result;
4395
4396 if (cmd_len < sizeof(*rsp))
4397 return -EPROTO;
4398
4399 type = __le16_to_cpu(rsp->type);
4400 result = __le16_to_cpu(rsp->result);
4401
4402 BT_DBG("type 0x%4.4x result 0x%2.2x", type, result);
4403
4404 /* L2CAP Info req/rsp are unbound to channels, add extra checks */
4405 if (cmd->ident != conn->info_ident ||
4406 conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE)
4407 return 0;
4408
4409 cancel_delayed_work(&conn->info_timer);
4410
4411 if (result != L2CAP_IR_SUCCESS) {
4412 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
4413 conn->info_ident = 0;
4414
4415 l2cap_conn_start(conn);
4416
4417 return 0;
4418 }
4419
4420 switch (type) {
4421 case L2CAP_IT_FEAT_MASK:
4422 conn->feat_mask = get_unaligned_le32(rsp->data);
4423
4424 if (conn->feat_mask & L2CAP_FEAT_FIXED_CHAN) {
4425 struct l2cap_info_req req;
4426 req.type = cpu_to_le16(L2CAP_IT_FIXED_CHAN);
4427
4428 conn->info_ident = l2cap_get_ident(conn);
4429
4430 l2cap_send_cmd(conn, conn->info_ident,
4431 L2CAP_INFO_REQ, sizeof(req), &req);
4432 } else {
4433 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
4434 conn->info_ident = 0;
4435
4436 l2cap_conn_start(conn);
4437 }
4438 break;
4439
4440 case L2CAP_IT_FIXED_CHAN:
4441 conn->remote_fixed_chan = rsp->data[0];
4442 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
4443 conn->info_ident = 0;
4444
4445 l2cap_conn_start(conn);
4446 break;
4447 }
4448
4449 return 0;
4450}
4451
4452static int l2cap_create_channel_req(struct l2cap_conn *conn,
4453 struct l2cap_cmd_hdr *cmd,
4454 u16 cmd_len, void *data)
4455{
4456 struct l2cap_create_chan_req *req = data;
4457 struct l2cap_create_chan_rsp rsp;
4458 struct l2cap_chan *chan;
4459 struct hci_dev *hdev;
4460 u16 psm, scid;
4461
4462 if (cmd_len != sizeof(*req))
4463 return -EPROTO;
4464
4465 if (!(conn->local_fixed_chan & L2CAP_FC_A2MP))
4466 return -EINVAL;
4467
4468 psm = le16_to_cpu(req->psm);
4469 scid = le16_to_cpu(req->scid);
4470
4471 BT_DBG("psm 0x%2.2x, scid 0x%4.4x, amp_id %d", psm, scid, req->amp_id);
4472
4473 /* For controller id 0 make BR/EDR connection */
4474 if (req->amp_id == AMP_ID_BREDR) {
4475 l2cap_connect(conn, cmd, data, L2CAP_CREATE_CHAN_RSP,
4476 req->amp_id);
4477 return 0;
4478 }
4479
4480 /* Validate AMP controller id */
4481 hdev = hci_dev_get(req->amp_id);
4482 if (!hdev)
4483 goto error;
4484
4485 if (hdev->dev_type != HCI_AMP || !test_bit(HCI_UP, &hdev->flags)) {
4486 hci_dev_put(hdev);
4487 goto error;
4488 }
4489
4490 chan = l2cap_connect(conn, cmd, data, L2CAP_CREATE_CHAN_RSP,
4491 req->amp_id);
4492 if (chan) {
4493 struct amp_mgr *mgr = conn->hcon->amp_mgr;
4494 struct hci_conn *hs_hcon;
4495
4496 hs_hcon = hci_conn_hash_lookup_ba(hdev, AMP_LINK,
4497 &conn->hcon->dst);
4498 if (!hs_hcon) {
4499 hci_dev_put(hdev);
4500 cmd_reject_invalid_cid(conn, cmd->ident, chan->scid,
4501 chan->dcid);
4502 return 0;
4503 }
4504
4505 BT_DBG("mgr %p bredr_chan %p hs_hcon %p", mgr, chan, hs_hcon);
4506
4507 mgr->bredr_chan = chan;
4508 chan->hs_hcon = hs_hcon;
4509 chan->fcs = L2CAP_FCS_NONE;
4510 conn->mtu = hdev->block_mtu;
4511 }
4512
4513 hci_dev_put(hdev);
4514
4515 return 0;
4516
4517error:
4518 rsp.dcid = 0;
4519 rsp.scid = cpu_to_le16(scid);
4520 rsp.result = cpu_to_le16(L2CAP_CR_BAD_AMP);
4521 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
4522
4523 l2cap_send_cmd(conn, cmd->ident, L2CAP_CREATE_CHAN_RSP,
4524 sizeof(rsp), &rsp);
4525
4526 return 0;
4527}
4528
4529static void l2cap_send_move_chan_req(struct l2cap_chan *chan, u8 dest_amp_id)
4530{
4531 struct l2cap_move_chan_req req;
4532 u8 ident;
4533
4534 BT_DBG("chan %p, dest_amp_id %d", chan, dest_amp_id);
4535
4536 ident = l2cap_get_ident(chan->conn);
4537 chan->ident = ident;
4538
4539 req.icid = cpu_to_le16(chan->scid);
4540 req.dest_amp_id = dest_amp_id;
4541
4542 l2cap_send_cmd(chan->conn, ident, L2CAP_MOVE_CHAN_REQ, sizeof(req),
4543 &req);
4544
4545 __set_chan_timer(chan, L2CAP_MOVE_TIMEOUT);
4546}
4547
4548static void l2cap_send_move_chan_rsp(struct l2cap_chan *chan, u16 result)
4549{
4550 struct l2cap_move_chan_rsp rsp;
4551
4552 BT_DBG("chan %p, result 0x%4.4x", chan, result);
4553
4554 rsp.icid = cpu_to_le16(chan->dcid);
4555 rsp.result = cpu_to_le16(result);
4556
4557 l2cap_send_cmd(chan->conn, chan->ident, L2CAP_MOVE_CHAN_RSP,
4558 sizeof(rsp), &rsp);
4559}
4560
4561static void l2cap_send_move_chan_cfm(struct l2cap_chan *chan, u16 result)
4562{
4563 struct l2cap_move_chan_cfm cfm;
4564
4565 BT_DBG("chan %p, result 0x%4.4x", chan, result);
4566
4567 chan->ident = l2cap_get_ident(chan->conn);
4568
4569 cfm.icid = cpu_to_le16(chan->scid);
4570 cfm.result = cpu_to_le16(result);
4571
4572 l2cap_send_cmd(chan->conn, chan->ident, L2CAP_MOVE_CHAN_CFM,
4573 sizeof(cfm), &cfm);
4574
4575 __set_chan_timer(chan, L2CAP_MOVE_TIMEOUT);
4576}
4577
4578static void l2cap_send_move_chan_cfm_icid(struct l2cap_conn *conn, u16 icid)
4579{
4580 struct l2cap_move_chan_cfm cfm;
4581
4582 BT_DBG("conn %p, icid 0x%4.4x", conn, icid);
4583
4584 cfm.icid = cpu_to_le16(icid);
4585 cfm.result = cpu_to_le16(L2CAP_MC_UNCONFIRMED);
4586
4587 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_MOVE_CHAN_CFM,
4588 sizeof(cfm), &cfm);
4589}
4590
4591static void l2cap_send_move_chan_cfm_rsp(struct l2cap_conn *conn, u8 ident,
4592 u16 icid)
4593{
4594 struct l2cap_move_chan_cfm_rsp rsp;
4595
4596 BT_DBG("icid 0x%4.4x", icid);
4597
4598 rsp.icid = cpu_to_le16(icid);
4599 l2cap_send_cmd(conn, ident, L2CAP_MOVE_CHAN_CFM_RSP, sizeof(rsp), &rsp);
4600}
4601
4602static void __release_logical_link(struct l2cap_chan *chan)
4603{
4604 chan->hs_hchan = NULL;
4605 chan->hs_hcon = NULL;
4606
4607 /* Placeholder - release the logical link */
4608}
4609
4610static void l2cap_logical_fail(struct l2cap_chan *chan)
4611{
4612 /* Logical link setup failed */
4613 if (chan->state != BT_CONNECTED) {
4614 /* Create channel failure, disconnect */
4615 l2cap_send_disconn_req(chan, ECONNRESET);
4616 return;
4617 }
4618
4619 switch (chan->move_role) {
4620 case L2CAP_MOVE_ROLE_RESPONDER:
4621 l2cap_move_done(chan);
4622 l2cap_send_move_chan_rsp(chan, L2CAP_MR_NOT_SUPP);
4623 break;
4624 case L2CAP_MOVE_ROLE_INITIATOR:
4625 if (chan->move_state == L2CAP_MOVE_WAIT_LOGICAL_COMP ||
4626 chan->move_state == L2CAP_MOVE_WAIT_LOGICAL_CFM) {
4627 /* Remote has only sent pending or
4628 * success responses, clean up
4629 */
4630 l2cap_move_done(chan);
4631 }
4632
4633 /* Other amp move states imply that the move
4634 * has already aborted
4635 */
4636 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
4637 break;
4638 }
4639}
4640
4641static void l2cap_logical_finish_create(struct l2cap_chan *chan,
4642 struct hci_chan *hchan)
4643{
4644 struct l2cap_conf_rsp rsp;
4645
4646 chan->hs_hchan = hchan;
4647 chan->hs_hcon->l2cap_data = chan->conn;
4648
4649 l2cap_send_efs_conf_rsp(chan, &rsp, chan->ident, 0);
4650
4651 if (test_bit(CONF_INPUT_DONE, &chan->conf_state)) {
4652 int err;
4653
4654 set_default_fcs(chan);
4655
4656 err = l2cap_ertm_init(chan);
4657 if (err < 0)
4658 l2cap_send_disconn_req(chan, -err);
4659 else
4660 l2cap_chan_ready(chan);
4661 }
4662}
4663
4664static void l2cap_logical_finish_move(struct l2cap_chan *chan,
4665 struct hci_chan *hchan)
4666{
4667 chan->hs_hcon = hchan->conn;
4668 chan->hs_hcon->l2cap_data = chan->conn;
4669
4670 BT_DBG("move_state %d", chan->move_state);
4671
4672 switch (chan->move_state) {
4673 case L2CAP_MOVE_WAIT_LOGICAL_COMP:
4674 /* Move confirm will be sent after a success
4675 * response is received
4676 */
4677 chan->move_state = L2CAP_MOVE_WAIT_RSP_SUCCESS;
4678 break;
4679 case L2CAP_MOVE_WAIT_LOGICAL_CFM:
4680 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
4681 chan->move_state = L2CAP_MOVE_WAIT_LOCAL_BUSY;
4682 } else if (chan->move_role == L2CAP_MOVE_ROLE_INITIATOR) {
4683 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM_RSP;
4684 l2cap_send_move_chan_cfm(chan, L2CAP_MC_CONFIRMED);
4685 } else if (chan->move_role == L2CAP_MOVE_ROLE_RESPONDER) {
4686 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM;
4687 l2cap_send_move_chan_rsp(chan, L2CAP_MR_SUCCESS);
4688 }
4689 break;
4690 default:
4691 /* Move was not in expected state, free the channel */
4692 __release_logical_link(chan);
4693
4694 chan->move_state = L2CAP_MOVE_STABLE;
4695 }
4696}
4697
4698/* Call with chan locked */
4699void l2cap_logical_cfm(struct l2cap_chan *chan, struct hci_chan *hchan,
4700 u8 status)
4701{
4702 BT_DBG("chan %p, hchan %p, status %d", chan, hchan, status);
4703
4704 if (status) {
4705 l2cap_logical_fail(chan);
4706 __release_logical_link(chan);
4707 return;
4708 }
4709
4710 if (chan->state != BT_CONNECTED) {
4711 /* Ignore logical link if channel is on BR/EDR */
4712 if (chan->local_amp_id != AMP_ID_BREDR)
4713 l2cap_logical_finish_create(chan, hchan);
4714 } else {
4715 l2cap_logical_finish_move(chan, hchan);
4716 }
4717}
4718
4719void l2cap_move_start(struct l2cap_chan *chan)
4720{
4721 BT_DBG("chan %p", chan);
4722
4723 if (chan->local_amp_id == AMP_ID_BREDR) {
4724 if (chan->chan_policy != BT_CHANNEL_POLICY_AMP_PREFERRED)
4725 return;
4726 chan->move_role = L2CAP_MOVE_ROLE_INITIATOR;
4727 chan->move_state = L2CAP_MOVE_WAIT_PREPARE;
4728 /* Placeholder - start physical link setup */
4729 } else {
4730 chan->move_role = L2CAP_MOVE_ROLE_INITIATOR;
4731 chan->move_state = L2CAP_MOVE_WAIT_RSP_SUCCESS;
4732 chan->move_id = 0;
4733 l2cap_move_setup(chan);
4734 l2cap_send_move_chan_req(chan, 0);
4735 }
4736}
4737
4738static void l2cap_do_create(struct l2cap_chan *chan, int result,
4739 u8 local_amp_id, u8 remote_amp_id)
4740{
4741 BT_DBG("chan %p state %s %u -> %u", chan, state_to_string(chan->state),
4742 local_amp_id, remote_amp_id);
4743
4744 chan->fcs = L2CAP_FCS_NONE;
4745
4746 /* Outgoing channel on AMP */
4747 if (chan->state == BT_CONNECT) {
4748 if (result == L2CAP_CR_SUCCESS) {
4749 chan->local_amp_id = local_amp_id;
4750 l2cap_send_create_chan_req(chan, remote_amp_id);
4751 } else {
4752 /* Revert to BR/EDR connect */
4753 l2cap_send_conn_req(chan);
4754 }
4755
4756 return;
4757 }
4758
4759 /* Incoming channel on AMP */
4760 if (__l2cap_no_conn_pending(chan)) {
4761 struct l2cap_conn_rsp rsp;
4762 char buf[128];
4763 rsp.scid = cpu_to_le16(chan->dcid);
4764 rsp.dcid = cpu_to_le16(chan->scid);
4765
4766 if (result == L2CAP_CR_SUCCESS) {
4767 /* Send successful response */
4768 rsp.result = cpu_to_le16(L2CAP_CR_SUCCESS);
4769 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
4770 } else {
4771 /* Send negative response */
4772 rsp.result = cpu_to_le16(L2CAP_CR_NO_MEM);
4773 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
4774 }
4775
4776 l2cap_send_cmd(chan->conn, chan->ident, L2CAP_CREATE_CHAN_RSP,
4777 sizeof(rsp), &rsp);
4778
4779 if (result == L2CAP_CR_SUCCESS) {
4780 l2cap_state_change(chan, BT_CONFIG);
4781 set_bit(CONF_REQ_SENT, &chan->conf_state);
4782 l2cap_send_cmd(chan->conn, l2cap_get_ident(chan->conn),
4783 L2CAP_CONF_REQ,
4784 l2cap_build_conf_req(chan, buf), buf);
4785 chan->num_conf_req++;
4786 }
4787 }
4788}
4789
4790static void l2cap_do_move_initiate(struct l2cap_chan *chan, u8 local_amp_id,
4791 u8 remote_amp_id)
4792{
4793 l2cap_move_setup(chan);
4794 chan->move_id = local_amp_id;
4795 chan->move_state = L2CAP_MOVE_WAIT_RSP;
4796
4797 l2cap_send_move_chan_req(chan, remote_amp_id);
4798}
4799
4800static void l2cap_do_move_respond(struct l2cap_chan *chan, int result)
4801{
4802 struct hci_chan *hchan = NULL;
4803
4804 /* Placeholder - get hci_chan for logical link */
4805
4806 if (hchan) {
4807 if (hchan->state == BT_CONNECTED) {
4808 /* Logical link is ready to go */
4809 chan->hs_hcon = hchan->conn;
4810 chan->hs_hcon->l2cap_data = chan->conn;
4811 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM;
4812 l2cap_send_move_chan_rsp(chan, L2CAP_MR_SUCCESS);
4813
4814 l2cap_logical_cfm(chan, hchan, L2CAP_MR_SUCCESS);
4815 } else {
4816 /* Wait for logical link to be ready */
4817 chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_CFM;
4818 }
4819 } else {
4820 /* Logical link not available */
4821 l2cap_send_move_chan_rsp(chan, L2CAP_MR_NOT_ALLOWED);
4822 }
4823}
4824
4825static void l2cap_do_move_cancel(struct l2cap_chan *chan, int result)
4826{
4827 if (chan->move_role == L2CAP_MOVE_ROLE_RESPONDER) {
4828 u8 rsp_result;
4829 if (result == -EINVAL)
4830 rsp_result = L2CAP_MR_BAD_ID;
4831 else
4832 rsp_result = L2CAP_MR_NOT_ALLOWED;
4833
4834 l2cap_send_move_chan_rsp(chan, rsp_result);
4835 }
4836
4837 chan->move_role = L2CAP_MOVE_ROLE_NONE;
4838 chan->move_state = L2CAP_MOVE_STABLE;
4839
4840 /* Restart data transmission */
4841 l2cap_ertm_send(chan);
4842}
4843
4844/* Invoke with locked chan */
4845void __l2cap_physical_cfm(struct l2cap_chan *chan, int result)
4846{
4847 u8 local_amp_id = chan->local_amp_id;
4848 u8 remote_amp_id = chan->remote_amp_id;
4849
4850 BT_DBG("chan %p, result %d, local_amp_id %d, remote_amp_id %d",
4851 chan, result, local_amp_id, remote_amp_id);
4852
4853 if (chan->state == BT_DISCONN || chan->state == BT_CLOSED) {
4854 l2cap_chan_unlock(chan);
4855 return;
4856 }
4857
4858 if (chan->state != BT_CONNECTED) {
4859 l2cap_do_create(chan, result, local_amp_id, remote_amp_id);
4860 } else if (result != L2CAP_MR_SUCCESS) {
4861 l2cap_do_move_cancel(chan, result);
4862 } else {
4863 switch (chan->move_role) {
4864 case L2CAP_MOVE_ROLE_INITIATOR:
4865 l2cap_do_move_initiate(chan, local_amp_id,
4866 remote_amp_id);
4867 break;
4868 case L2CAP_MOVE_ROLE_RESPONDER:
4869 l2cap_do_move_respond(chan, result);
4870 break;
4871 default:
4872 l2cap_do_move_cancel(chan, result);
4873 break;
4874 }
4875 }
4876}
4877
4878static inline int l2cap_move_channel_req(struct l2cap_conn *conn,
4879 struct l2cap_cmd_hdr *cmd,
4880 u16 cmd_len, void *data)
4881{
4882 struct l2cap_move_chan_req *req = data;
4883 struct l2cap_move_chan_rsp rsp;
4884 struct l2cap_chan *chan;
4885 u16 icid = 0;
4886 u16 result = L2CAP_MR_NOT_ALLOWED;
4887
4888 if (cmd_len != sizeof(*req))
4889 return -EPROTO;
4890
4891 icid = le16_to_cpu(req->icid);
4892
4893 BT_DBG("icid 0x%4.4x, dest_amp_id %d", icid, req->dest_amp_id);
4894
4895 if (!(conn->local_fixed_chan & L2CAP_FC_A2MP))
4896 return -EINVAL;
4897
4898 chan = l2cap_get_chan_by_dcid(conn, icid);
4899 if (!chan) {
4900 rsp.icid = cpu_to_le16(icid);
4901 rsp.result = cpu_to_le16(L2CAP_MR_NOT_ALLOWED);
4902 l2cap_send_cmd(conn, cmd->ident, L2CAP_MOVE_CHAN_RSP,
4903 sizeof(rsp), &rsp);
4904 return 0;
4905 }
4906
4907 chan->ident = cmd->ident;
4908
4909 if (chan->scid < L2CAP_CID_DYN_START ||
4910 chan->chan_policy == BT_CHANNEL_POLICY_BREDR_ONLY ||
4911 (chan->mode != L2CAP_MODE_ERTM &&
4912 chan->mode != L2CAP_MODE_STREAMING)) {
4913 result = L2CAP_MR_NOT_ALLOWED;
4914 goto send_move_response;
4915 }
4916
4917 if (chan->local_amp_id == req->dest_amp_id) {
4918 result = L2CAP_MR_SAME_ID;
4919 goto send_move_response;
4920 }
4921
4922 if (req->dest_amp_id != AMP_ID_BREDR) {
4923 struct hci_dev *hdev;
4924 hdev = hci_dev_get(req->dest_amp_id);
4925 if (!hdev || hdev->dev_type != HCI_AMP ||
4926 !test_bit(HCI_UP, &hdev->flags)) {
4927 if (hdev)
4928 hci_dev_put(hdev);
4929
4930 result = L2CAP_MR_BAD_ID;
4931 goto send_move_response;
4932 }
4933 hci_dev_put(hdev);
4934 }
4935
4936 /* Detect a move collision. Only send a collision response
4937 * if this side has "lost", otherwise proceed with the move.
4938 * The winner has the larger bd_addr.
4939 */
4940 if ((__chan_is_moving(chan) ||
4941 chan->move_role != L2CAP_MOVE_ROLE_NONE) &&
4942 bacmp(&conn->hcon->src, &conn->hcon->dst) > 0) {
4943 result = L2CAP_MR_COLLISION;
4944 goto send_move_response;
4945 }
4946
4947 chan->move_role = L2CAP_MOVE_ROLE_RESPONDER;
4948 l2cap_move_setup(chan);
4949 chan->move_id = req->dest_amp_id;
4950 icid = chan->dcid;
4951
4952 if (req->dest_amp_id == AMP_ID_BREDR) {
4953 /* Moving to BR/EDR */
4954 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
4955 chan->move_state = L2CAP_MOVE_WAIT_LOCAL_BUSY;
4956 result = L2CAP_MR_PEND;
4957 } else {
4958 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM;
4959 result = L2CAP_MR_SUCCESS;
4960 }
4961 } else {
4962 chan->move_state = L2CAP_MOVE_WAIT_PREPARE;
4963 /* Placeholder - uncomment when amp functions are available */
4964 /*amp_accept_physical(chan, req->dest_amp_id);*/
4965 result = L2CAP_MR_PEND;
4966 }
4967
4968send_move_response:
4969 l2cap_send_move_chan_rsp(chan, result);
4970
4971 l2cap_chan_unlock(chan);
4972
4973 return 0;
4974}
4975
4976static void l2cap_move_continue(struct l2cap_conn *conn, u16 icid, u16 result)
4977{
4978 struct l2cap_chan *chan;
4979 struct hci_chan *hchan = NULL;
4980
4981 chan = l2cap_get_chan_by_scid(conn, icid);
4982 if (!chan) {
4983 l2cap_send_move_chan_cfm_icid(conn, icid);
4984 return;
4985 }
4986
4987 __clear_chan_timer(chan);
4988 if (result == L2CAP_MR_PEND)
4989 __set_chan_timer(chan, L2CAP_MOVE_ERTX_TIMEOUT);
4990
4991 switch (chan->move_state) {
4992 case L2CAP_MOVE_WAIT_LOGICAL_COMP:
4993 /* Move confirm will be sent when logical link
4994 * is complete.
4995 */
4996 chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_CFM;
4997 break;
4998 case L2CAP_MOVE_WAIT_RSP_SUCCESS:
4999 if (result == L2CAP_MR_PEND) {
5000 break;
5001 } else if (test_bit(CONN_LOCAL_BUSY,
5002 &chan->conn_state)) {
5003 chan->move_state = L2CAP_MOVE_WAIT_LOCAL_BUSY;
5004 } else {
5005 /* Logical link is up or moving to BR/EDR,
5006 * proceed with move
5007 */
5008 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM_RSP;
5009 l2cap_send_move_chan_cfm(chan, L2CAP_MC_CONFIRMED);
5010 }
5011 break;
5012 case L2CAP_MOVE_WAIT_RSP:
5013 /* Moving to AMP */
5014 if (result == L2CAP_MR_SUCCESS) {
5015 /* Remote is ready, send confirm immediately
5016 * after logical link is ready
5017 */
5018 chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_CFM;
5019 } else {
5020 /* Both logical link and move success
5021 * are required to confirm
5022 */
5023 chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_COMP;
5024 }
5025
5026 /* Placeholder - get hci_chan for logical link */
5027 if (!hchan) {
5028 /* Logical link not available */
5029 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
5030 break;
5031 }
5032
5033 /* If the logical link is not yet connected, do not
5034 * send confirmation.
5035 */
5036 if (hchan->state != BT_CONNECTED)
5037 break;
5038
5039 /* Logical link is already ready to go */
5040
5041 chan->hs_hcon = hchan->conn;
5042 chan->hs_hcon->l2cap_data = chan->conn;
5043
5044 if (result == L2CAP_MR_SUCCESS) {
5045 /* Can confirm now */
5046 l2cap_send_move_chan_cfm(chan, L2CAP_MC_CONFIRMED);
5047 } else {
5048 /* Now only need move success
5049 * to confirm
5050 */
5051 chan->move_state = L2CAP_MOVE_WAIT_RSP_SUCCESS;
5052 }
5053
5054 l2cap_logical_cfm(chan, hchan, L2CAP_MR_SUCCESS);
5055 break;
5056 default:
5057 /* Any other amp move state means the move failed. */
5058 chan->move_id = chan->local_amp_id;
5059 l2cap_move_done(chan);
5060 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
5061 }
5062
5063 l2cap_chan_unlock(chan);
5064}
5065
5066static void l2cap_move_fail(struct l2cap_conn *conn, u8 ident, u16 icid,
5067 u16 result)
5068{
5069 struct l2cap_chan *chan;
5070
5071 chan = l2cap_get_chan_by_ident(conn, ident);
5072 if (!chan) {
5073 /* Could not locate channel, icid is best guess */
5074 l2cap_send_move_chan_cfm_icid(conn, icid);
5075 return;
5076 }
5077
5078 __clear_chan_timer(chan);
5079
5080 if (chan->move_role == L2CAP_MOVE_ROLE_INITIATOR) {
5081 if (result == L2CAP_MR_COLLISION) {
5082 chan->move_role = L2CAP_MOVE_ROLE_RESPONDER;
5083 } else {
5084 /* Cleanup - cancel move */
5085 chan->move_id = chan->local_amp_id;
5086 l2cap_move_done(chan);
5087 }
5088 }
5089
5090 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
5091
5092 l2cap_chan_unlock(chan);
5093}
5094
5095static int l2cap_move_channel_rsp(struct l2cap_conn *conn,
5096 struct l2cap_cmd_hdr *cmd,
5097 u16 cmd_len, void *data)
5098{
5099 struct l2cap_move_chan_rsp *rsp = data;
5100 u16 icid, result;
5101
5102 if (cmd_len != sizeof(*rsp))
5103 return -EPROTO;
5104
5105 icid = le16_to_cpu(rsp->icid);
5106 result = le16_to_cpu(rsp->result);
5107
5108 BT_DBG("icid 0x%4.4x, result 0x%4.4x", icid, result);
5109
5110 if (result == L2CAP_MR_SUCCESS || result == L2CAP_MR_PEND)
5111 l2cap_move_continue(conn, icid, result);
5112 else
5113 l2cap_move_fail(conn, cmd->ident, icid, result);
5114
5115 return 0;
5116}
5117
5118static int l2cap_move_channel_confirm(struct l2cap_conn *conn,
5119 struct l2cap_cmd_hdr *cmd,
5120 u16 cmd_len, void *data)
5121{
5122 struct l2cap_move_chan_cfm *cfm = data;
5123 struct l2cap_chan *chan;
5124 u16 icid, result;
5125
5126 if (cmd_len != sizeof(*cfm))
5127 return -EPROTO;
5128
5129 icid = le16_to_cpu(cfm->icid);
5130 result = le16_to_cpu(cfm->result);
5131
5132 BT_DBG("icid 0x%4.4x, result 0x%4.4x", icid, result);
5133
5134 chan = l2cap_get_chan_by_dcid(conn, icid);
5135 if (!chan) {
5136 /* Spec requires a response even if the icid was not found */
5137 l2cap_send_move_chan_cfm_rsp(conn, cmd->ident, icid);
5138 return 0;
5139 }
5140
5141 if (chan->move_state == L2CAP_MOVE_WAIT_CONFIRM) {
5142 if (result == L2CAP_MC_CONFIRMED) {
5143 chan->local_amp_id = chan->move_id;
5144 if (chan->local_amp_id == AMP_ID_BREDR)
5145 __release_logical_link(chan);
5146 } else {
5147 chan->move_id = chan->local_amp_id;
5148 }
5149
5150 l2cap_move_done(chan);
5151 }
5152
5153 l2cap_send_move_chan_cfm_rsp(conn, cmd->ident, icid);
5154
5155 l2cap_chan_unlock(chan);
5156
5157 return 0;
5158}
5159
5160static inline int l2cap_move_channel_confirm_rsp(struct l2cap_conn *conn,
5161 struct l2cap_cmd_hdr *cmd,
5162 u16 cmd_len, void *data)
5163{
5164 struct l2cap_move_chan_cfm_rsp *rsp = data;
5165 struct l2cap_chan *chan;
5166 u16 icid;
5167
5168 if (cmd_len != sizeof(*rsp))
5169 return -EPROTO;
5170
5171 icid = le16_to_cpu(rsp->icid);
5172
5173 BT_DBG("icid 0x%4.4x", icid);
5174
5175 chan = l2cap_get_chan_by_scid(conn, icid);
5176 if (!chan)
5177 return 0;
5178
5179 __clear_chan_timer(chan);
5180
5181 if (chan->move_state == L2CAP_MOVE_WAIT_CONFIRM_RSP) {
5182 chan->local_amp_id = chan->move_id;
5183
5184 if (chan->local_amp_id == AMP_ID_BREDR && chan->hs_hchan)
5185 __release_logical_link(chan);
5186
5187 l2cap_move_done(chan);
5188 }
5189
5190 l2cap_chan_unlock(chan);
5191
5192 return 0;
5193}
5194
5195static inline int l2cap_conn_param_update_req(struct l2cap_conn *conn,
5196 struct l2cap_cmd_hdr *cmd,
5197 u16 cmd_len, u8 *data)
5198{
5199 struct hci_conn *hcon = conn->hcon;
5200 struct l2cap_conn_param_update_req *req;
5201 struct l2cap_conn_param_update_rsp rsp;
5202 u16 min, max, latency, to_multiplier;
5203 int err;
5204
5205 if (hcon->role != HCI_ROLE_MASTER)
5206 return -EINVAL;
5207
5208 if (cmd_len != sizeof(struct l2cap_conn_param_update_req))
5209 return -EPROTO;
5210
5211 req = (struct l2cap_conn_param_update_req *) data;
5212 min = __le16_to_cpu(req->min);
5213 max = __le16_to_cpu(req->max);
5214 latency = __le16_to_cpu(req->latency);
5215 to_multiplier = __le16_to_cpu(req->to_multiplier);
5216
5217 BT_DBG("min 0x%4.4x max 0x%4.4x latency: 0x%4.4x Timeout: 0x%4.4x",
5218 min, max, latency, to_multiplier);
5219
5220 memset(&rsp, 0, sizeof(rsp));
5221
5222 err = hci_check_conn_params(min, max, latency, to_multiplier);
5223 if (err)
5224 rsp.result = cpu_to_le16(L2CAP_CONN_PARAM_REJECTED);
5225 else
5226 rsp.result = cpu_to_le16(L2CAP_CONN_PARAM_ACCEPTED);
5227
5228 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONN_PARAM_UPDATE_RSP,
5229 sizeof(rsp), &rsp);
5230
5231 if (!err) {
5232 u8 store_hint;
5233
5234 store_hint = hci_le_conn_update(hcon, min, max, latency,
5235 to_multiplier);
5236 mgmt_new_conn_param(hcon->hdev, &hcon->dst, hcon->dst_type,
5237 store_hint, min, max, latency,
5238 to_multiplier);
5239
5240 }
5241
5242 return 0;
5243}
5244
5245static int l2cap_le_connect_rsp(struct l2cap_conn *conn,
5246 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5247 u8 *data)
5248{
5249 struct l2cap_le_conn_rsp *rsp = (struct l2cap_le_conn_rsp *) data;
5250 struct hci_conn *hcon = conn->hcon;
5251 u16 dcid, mtu, mps, credits, result;
5252 struct l2cap_chan *chan;
5253 int err, sec_level;
5254
5255 if (cmd_len < sizeof(*rsp))
5256 return -EPROTO;
5257
5258 dcid = __le16_to_cpu(rsp->dcid);
5259 mtu = __le16_to_cpu(rsp->mtu);
5260 mps = __le16_to_cpu(rsp->mps);
5261 credits = __le16_to_cpu(rsp->credits);
5262 result = __le16_to_cpu(rsp->result);
5263
5264 if (result == L2CAP_CR_SUCCESS && (mtu < 23 || mps < 23 ||
5265 dcid < L2CAP_CID_DYN_START ||
5266 dcid > L2CAP_CID_LE_DYN_END))
5267 return -EPROTO;
5268
5269 BT_DBG("dcid 0x%4.4x mtu %u mps %u credits %u result 0x%2.2x",
5270 dcid, mtu, mps, credits, result);
5271
5272 mutex_lock(&conn->chan_lock);
5273
5274 chan = __l2cap_get_chan_by_ident(conn, cmd->ident);
5275 if (!chan) {
5276 err = -EBADSLT;
5277 goto unlock;
5278 }
5279
5280 err = 0;
5281
5282 l2cap_chan_lock(chan);
5283
5284 switch (result) {
5285 case L2CAP_CR_SUCCESS:
5286 if (__l2cap_get_chan_by_dcid(conn, dcid)) {
5287 err = -EBADSLT;
5288 break;
5289 }
5290
5291 chan->ident = 0;
5292 chan->dcid = dcid;
5293 chan->omtu = mtu;
5294 chan->remote_mps = mps;
5295 chan->tx_credits = credits;
5296 l2cap_chan_ready(chan);
5297 break;
5298
5299 case L2CAP_CR_AUTHENTICATION:
5300 case L2CAP_CR_ENCRYPTION:
5301 /* If we already have MITM protection we can't do
5302 * anything.
5303 */
5304 if (hcon->sec_level > BT_SECURITY_MEDIUM) {
5305 l2cap_chan_del(chan, ECONNREFUSED);
5306 break;
5307 }
5308
5309 sec_level = hcon->sec_level + 1;
5310 if (chan->sec_level < sec_level)
5311 chan->sec_level = sec_level;
5312
5313 /* We'll need to send a new Connect Request */
5314 clear_bit(FLAG_LE_CONN_REQ_SENT, &chan->flags);
5315
5316 smp_conn_security(hcon, chan->sec_level);
5317 break;
5318
5319 default:
5320 l2cap_chan_del(chan, ECONNREFUSED);
5321 break;
5322 }
5323
5324 l2cap_chan_unlock(chan);
5325
5326unlock:
5327 mutex_unlock(&conn->chan_lock);
5328
5329 return err;
5330}
5331
5332static inline int l2cap_bredr_sig_cmd(struct l2cap_conn *conn,
5333 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5334 u8 *data)
5335{
5336 int err = 0;
5337
5338 switch (cmd->code) {
5339 case L2CAP_COMMAND_REJ:
5340 l2cap_command_rej(conn, cmd, cmd_len, data);
5341 break;
5342
5343 case L2CAP_CONN_REQ:
5344 err = l2cap_connect_req(conn, cmd, cmd_len, data);
5345 break;
5346
5347 case L2CAP_CONN_RSP:
5348 case L2CAP_CREATE_CHAN_RSP:
5349 l2cap_connect_create_rsp(conn, cmd, cmd_len, data);
5350 break;
5351
5352 case L2CAP_CONF_REQ:
5353 err = l2cap_config_req(conn, cmd, cmd_len, data);
5354 break;
5355
5356 case L2CAP_CONF_RSP:
5357 l2cap_config_rsp(conn, cmd, cmd_len, data);
5358 break;
5359
5360 case L2CAP_DISCONN_REQ:
5361 err = l2cap_disconnect_req(conn, cmd, cmd_len, data);
5362 break;
5363
5364 case L2CAP_DISCONN_RSP:
5365 l2cap_disconnect_rsp(conn, cmd, cmd_len, data);
5366 break;
5367
5368 case L2CAP_ECHO_REQ:
5369 l2cap_send_cmd(conn, cmd->ident, L2CAP_ECHO_RSP, cmd_len, data);
5370 break;
5371
5372 case L2CAP_ECHO_RSP:
5373 break;
5374
5375 case L2CAP_INFO_REQ:
5376 err = l2cap_information_req(conn, cmd, cmd_len, data);
5377 break;
5378
5379 case L2CAP_INFO_RSP:
5380 l2cap_information_rsp(conn, cmd, cmd_len, data);
5381 break;
5382
5383 case L2CAP_CREATE_CHAN_REQ:
5384 err = l2cap_create_channel_req(conn, cmd, cmd_len, data);
5385 break;
5386
5387 case L2CAP_MOVE_CHAN_REQ:
5388 err = l2cap_move_channel_req(conn, cmd, cmd_len, data);
5389 break;
5390
5391 case L2CAP_MOVE_CHAN_RSP:
5392 l2cap_move_channel_rsp(conn, cmd, cmd_len, data);
5393 break;
5394
5395 case L2CAP_MOVE_CHAN_CFM:
5396 err = l2cap_move_channel_confirm(conn, cmd, cmd_len, data);
5397 break;
5398
5399 case L2CAP_MOVE_CHAN_CFM_RSP:
5400 l2cap_move_channel_confirm_rsp(conn, cmd, cmd_len, data);
5401 break;
5402
5403 default:
5404 BT_ERR("Unknown BR/EDR signaling command 0x%2.2x", cmd->code);
5405 err = -EINVAL;
5406 break;
5407 }
5408
5409 return err;
5410}
5411
5412static int l2cap_le_connect_req(struct l2cap_conn *conn,
5413 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5414 u8 *data)
5415{
5416 struct l2cap_le_conn_req *req = (struct l2cap_le_conn_req *) data;
5417 struct l2cap_le_conn_rsp rsp;
5418 struct l2cap_chan *chan, *pchan;
5419 u16 dcid, scid, credits, mtu, mps;
5420 __le16 psm;
5421 u8 result;
5422
5423 if (cmd_len != sizeof(*req))
5424 return -EPROTO;
5425
5426 scid = __le16_to_cpu(req->scid);
5427 mtu = __le16_to_cpu(req->mtu);
5428 mps = __le16_to_cpu(req->mps);
5429 psm = req->psm;
5430 dcid = 0;
5431 credits = 0;
5432
5433 if (mtu < 23 || mps < 23)
5434 return -EPROTO;
5435
5436 BT_DBG("psm 0x%2.2x scid 0x%4.4x mtu %u mps %u", __le16_to_cpu(psm),
5437 scid, mtu, mps);
5438
5439 /* Check if we have socket listening on psm */
5440 pchan = l2cap_global_chan_by_psm(BT_LISTEN, psm, &conn->hcon->src,
5441 &conn->hcon->dst, LE_LINK);
5442 if (!pchan) {
5443 result = L2CAP_CR_BAD_PSM;
5444 chan = NULL;
5445 goto response;
5446 }
5447
5448 mutex_lock(&conn->chan_lock);
5449 l2cap_chan_lock(pchan);
5450
5451 if (!smp_sufficient_security(conn->hcon, pchan->sec_level,
5452 SMP_ALLOW_STK)) {
5453 result = L2CAP_CR_AUTHENTICATION;
5454 chan = NULL;
5455 goto response_unlock;
5456 }
5457
5458 /* Check for valid dynamic CID range */
5459 if (scid < L2CAP_CID_DYN_START || scid > L2CAP_CID_LE_DYN_END) {
5460 result = L2CAP_CR_INVALID_SCID;
5461 chan = NULL;
5462 goto response_unlock;
5463 }
5464
5465 /* Check if we already have channel with that dcid */
5466 if (__l2cap_get_chan_by_dcid(conn, scid)) {
5467 result = L2CAP_CR_SCID_IN_USE;
5468 chan = NULL;
5469 goto response_unlock;
5470 }
5471
5472 chan = pchan->ops->new_connection(pchan);
5473 if (!chan) {
5474 result = L2CAP_CR_NO_MEM;
5475 goto response_unlock;
5476 }
5477
5478 l2cap_le_flowctl_init(chan);
5479
5480 bacpy(&chan->src, &conn->hcon->src);
5481 bacpy(&chan->dst, &conn->hcon->dst);
5482 chan->src_type = bdaddr_src_type(conn->hcon);
5483 chan->dst_type = bdaddr_dst_type(conn->hcon);
5484 chan->psm = psm;
5485 chan->dcid = scid;
5486 chan->omtu = mtu;
5487 chan->remote_mps = mps;
5488 chan->tx_credits = __le16_to_cpu(req->credits);
5489
5490 __l2cap_chan_add(conn, chan);
5491 dcid = chan->scid;
5492 credits = chan->rx_credits;
5493
5494 __set_chan_timer(chan, chan->ops->get_sndtimeo(chan));
5495
5496 chan->ident = cmd->ident;
5497
5498 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) {
5499 l2cap_state_change(chan, BT_CONNECT2);
5500 /* The following result value is actually not defined
5501 * for LE CoC but we use it to let the function know
5502 * that it should bail out after doing its cleanup
5503 * instead of sending a response.
5504 */
5505 result = L2CAP_CR_PEND;
5506 chan->ops->defer(chan);
5507 } else {
5508 l2cap_chan_ready(chan);
5509 result = L2CAP_CR_SUCCESS;
5510 }
5511
5512response_unlock:
5513 l2cap_chan_unlock(pchan);
5514 mutex_unlock(&conn->chan_lock);
5515 l2cap_chan_put(pchan);
5516
5517 if (result == L2CAP_CR_PEND)
5518 return 0;
5519
5520response:
5521 if (chan) {
5522 rsp.mtu = cpu_to_le16(chan->imtu);
5523 rsp.mps = cpu_to_le16(chan->mps);
5524 } else {
5525 rsp.mtu = 0;
5526 rsp.mps = 0;
5527 }
5528
5529 rsp.dcid = cpu_to_le16(dcid);
5530 rsp.credits = cpu_to_le16(credits);
5531 rsp.result = cpu_to_le16(result);
5532
5533 l2cap_send_cmd(conn, cmd->ident, L2CAP_LE_CONN_RSP, sizeof(rsp), &rsp);
5534
5535 return 0;
5536}
5537
5538static inline int l2cap_le_credits(struct l2cap_conn *conn,
5539 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5540 u8 *data)
5541{
5542 struct l2cap_le_credits *pkt;
5543 struct l2cap_chan *chan;
5544 u16 cid, credits, max_credits;
5545
5546 if (cmd_len != sizeof(*pkt))
5547 return -EPROTO;
5548
5549 pkt = (struct l2cap_le_credits *) data;
5550 cid = __le16_to_cpu(pkt->cid);
5551 credits = __le16_to_cpu(pkt->credits);
5552
5553 BT_DBG("cid 0x%4.4x credits 0x%4.4x", cid, credits);
5554
5555 chan = l2cap_get_chan_by_dcid(conn, cid);
5556 if (!chan)
5557 return -EBADSLT;
5558
5559 max_credits = LE_FLOWCTL_MAX_CREDITS - chan->tx_credits;
5560 if (credits > max_credits) {
5561 BT_ERR("LE credits overflow");
5562 l2cap_send_disconn_req(chan, ECONNRESET);
5563 l2cap_chan_unlock(chan);
5564
5565 /* Return 0 so that we don't trigger an unnecessary
5566 * command reject packet.
5567 */
5568 return 0;
5569 }
5570
5571 chan->tx_credits += credits;
5572
5573 while (chan->tx_credits && !skb_queue_empty(&chan->tx_q)) {
5574 l2cap_do_send(chan, skb_dequeue(&chan->tx_q));
5575 chan->tx_credits--;
5576 }
5577
5578 if (chan->tx_credits)
5579 chan->ops->resume(chan);
5580
5581 l2cap_chan_unlock(chan);
5582
5583 return 0;
5584}
5585
5586static inline int l2cap_le_command_rej(struct l2cap_conn *conn,
5587 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5588 u8 *data)
5589{
5590 struct l2cap_cmd_rej_unk *rej = (struct l2cap_cmd_rej_unk *) data;
5591 struct l2cap_chan *chan;
5592
5593 if (cmd_len < sizeof(*rej))
5594 return -EPROTO;
5595
5596 mutex_lock(&conn->chan_lock);
5597
5598 chan = __l2cap_get_chan_by_ident(conn, cmd->ident);
5599 if (!chan)
5600 goto done;
5601
5602 l2cap_chan_lock(chan);
5603 l2cap_chan_del(chan, ECONNREFUSED);
5604 l2cap_chan_unlock(chan);
5605
5606done:
5607 mutex_unlock(&conn->chan_lock);
5608 return 0;
5609}
5610
5611static inline int l2cap_le_sig_cmd(struct l2cap_conn *conn,
5612 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5613 u8 *data)
5614{
5615 int err = 0;
5616
5617 switch (cmd->code) {
5618 case L2CAP_COMMAND_REJ:
5619 l2cap_le_command_rej(conn, cmd, cmd_len, data);
5620 break;
5621
5622 case L2CAP_CONN_PARAM_UPDATE_REQ:
5623 err = l2cap_conn_param_update_req(conn, cmd, cmd_len, data);
5624 break;
5625
5626 case L2CAP_CONN_PARAM_UPDATE_RSP:
5627 break;
5628
5629 case L2CAP_LE_CONN_RSP:
5630 l2cap_le_connect_rsp(conn, cmd, cmd_len, data);
5631 break;
5632
5633 case L2CAP_LE_CONN_REQ:
5634 err = l2cap_le_connect_req(conn, cmd, cmd_len, data);
5635 break;
5636
5637 case L2CAP_LE_CREDITS:
5638 err = l2cap_le_credits(conn, cmd, cmd_len, data);
5639 break;
5640
5641 case L2CAP_DISCONN_REQ:
5642 err = l2cap_disconnect_req(conn, cmd, cmd_len, data);
5643 break;
5644
5645 case L2CAP_DISCONN_RSP:
5646 l2cap_disconnect_rsp(conn, cmd, cmd_len, data);
5647 break;
5648
5649 default:
5650 BT_ERR("Unknown LE signaling command 0x%2.2x", cmd->code);
5651 err = -EINVAL;
5652 break;
5653 }
5654
5655 return err;
5656}
5657
5658static inline void l2cap_le_sig_channel(struct l2cap_conn *conn,
5659 struct sk_buff *skb)
5660{
5661 struct hci_conn *hcon = conn->hcon;
5662 struct l2cap_cmd_hdr *cmd;
5663 u16 len;
5664 int err;
5665
5666 if (hcon->type != LE_LINK)
5667 goto drop;
5668
5669 if (skb->len < L2CAP_CMD_HDR_SIZE)
5670 goto drop;
5671
5672 cmd = (void *) skb->data;
5673 skb_pull(skb, L2CAP_CMD_HDR_SIZE);
5674
5675 len = le16_to_cpu(cmd->len);
5676
5677 BT_DBG("code 0x%2.2x len %d id 0x%2.2x", cmd->code, len, cmd->ident);
5678
5679 if (len != skb->len || !cmd->ident) {
5680 BT_DBG("corrupted command");
5681 goto drop;
5682 }
5683
5684 err = l2cap_le_sig_cmd(conn, cmd, len, skb->data);
5685 if (err) {
5686 struct l2cap_cmd_rej_unk rej;
5687
5688 BT_ERR("Wrong link type (%d)", err);
5689
5690 rej.reason = cpu_to_le16(L2CAP_REJ_NOT_UNDERSTOOD);
5691 l2cap_send_cmd(conn, cmd->ident, L2CAP_COMMAND_REJ,
5692 sizeof(rej), &rej);
5693 }
5694
5695drop:
5696 kfree_skb(skb);
5697}
5698
5699static inline void l2cap_sig_channel(struct l2cap_conn *conn,
5700 struct sk_buff *skb)
5701{
5702 struct hci_conn *hcon = conn->hcon;
5703 u8 *data = skb->data;
5704 int len = skb->len;
5705 struct l2cap_cmd_hdr cmd;
5706 int err;
5707
5708 l2cap_raw_recv(conn, skb);
5709
5710 if (hcon->type != ACL_LINK)
5711 goto drop;
5712
5713 while (len >= L2CAP_CMD_HDR_SIZE) {
5714 u16 cmd_len;
5715 memcpy(&cmd, data, L2CAP_CMD_HDR_SIZE);
5716 data += L2CAP_CMD_HDR_SIZE;
5717 len -= L2CAP_CMD_HDR_SIZE;
5718
5719 cmd_len = le16_to_cpu(cmd.len);
5720
5721 BT_DBG("code 0x%2.2x len %d id 0x%2.2x", cmd.code, cmd_len,
5722 cmd.ident);
5723
5724 if (cmd_len > len || !cmd.ident) {
5725 BT_DBG("corrupted command");
5726 break;
5727 }
5728
5729 err = l2cap_bredr_sig_cmd(conn, &cmd, cmd_len, data);
5730 if (err) {
5731 struct l2cap_cmd_rej_unk rej;
5732
5733 BT_ERR("Wrong link type (%d)", err);
5734
5735 rej.reason = cpu_to_le16(L2CAP_REJ_NOT_UNDERSTOOD);
5736 l2cap_send_cmd(conn, cmd.ident, L2CAP_COMMAND_REJ,
5737 sizeof(rej), &rej);
5738 }
5739
5740 data += cmd_len;
5741 len -= cmd_len;
5742 }
5743
5744drop:
5745 kfree_skb(skb);
5746}
5747
5748static int l2cap_check_fcs(struct l2cap_chan *chan, struct sk_buff *skb)
5749{
5750 u16 our_fcs, rcv_fcs;
5751 int hdr_size;
5752
5753 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
5754 hdr_size = L2CAP_EXT_HDR_SIZE;
5755 else
5756 hdr_size = L2CAP_ENH_HDR_SIZE;
5757
5758 if (chan->fcs == L2CAP_FCS_CRC16) {
5759 skb_trim(skb, skb->len - L2CAP_FCS_SIZE);
5760 rcv_fcs = get_unaligned_le16(skb->data + skb->len);
5761 our_fcs = crc16(0, skb->data - hdr_size, skb->len + hdr_size);
5762
5763 if (our_fcs != rcv_fcs)
5764 return -EBADMSG;
5765 }
5766 return 0;
5767}
5768
5769static void l2cap_send_i_or_rr_or_rnr(struct l2cap_chan *chan)
5770{
5771 struct l2cap_ctrl control;
5772
5773 BT_DBG("chan %p", chan);
5774
5775 memset(&control, 0, sizeof(control));
5776 control.sframe = 1;
5777 control.final = 1;
5778 control.reqseq = chan->buffer_seq;
5779 set_bit(CONN_SEND_FBIT, &chan->conn_state);
5780
5781 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
5782 control.super = L2CAP_SUPER_RNR;
5783 l2cap_send_sframe(chan, &control);
5784 }
5785
5786 if (test_and_clear_bit(CONN_REMOTE_BUSY, &chan->conn_state) &&
5787 chan->unacked_frames > 0)
5788 __set_retrans_timer(chan);
5789
5790 /* Send pending iframes */
5791 l2cap_ertm_send(chan);
5792
5793 if (!test_bit(CONN_LOCAL_BUSY, &chan->conn_state) &&
5794 test_bit(CONN_SEND_FBIT, &chan->conn_state)) {
5795 /* F-bit wasn't sent in an s-frame or i-frame yet, so
5796 * send it now.
5797 */
5798 control.super = L2CAP_SUPER_RR;
5799 l2cap_send_sframe(chan, &control);
5800 }
5801}
5802
5803static void append_skb_frag(struct sk_buff *skb, struct sk_buff *new_frag,
5804 struct sk_buff **last_frag)
5805{
5806 /* skb->len reflects data in skb as well as all fragments
5807 * skb->data_len reflects only data in fragments
5808 */
5809 if (!skb_has_frag_list(skb))
5810 skb_shinfo(skb)->frag_list = new_frag;
5811
5812 new_frag->next = NULL;
5813
5814 (*last_frag)->next = new_frag;
5815 *last_frag = new_frag;
5816
5817 skb->len += new_frag->len;
5818 skb->data_len += new_frag->len;
5819 skb->truesize += new_frag->truesize;
5820}
5821
5822static int l2cap_reassemble_sdu(struct l2cap_chan *chan, struct sk_buff *skb,
5823 struct l2cap_ctrl *control)
5824{
5825 int err = -EINVAL;
5826
5827 switch (control->sar) {
5828 case L2CAP_SAR_UNSEGMENTED:
5829 if (chan->sdu)
5830 break;
5831
5832 err = chan->ops->recv(chan, skb);
5833 break;
5834
5835 case L2CAP_SAR_START:
5836 if (chan->sdu)
5837 break;
5838
5839 if (!pskb_may_pull(skb, L2CAP_SDULEN_SIZE))
5840 break;
5841
5842 chan->sdu_len = get_unaligned_le16(skb->data);
5843 skb_pull(skb, L2CAP_SDULEN_SIZE);
5844
5845 if (chan->sdu_len > chan->imtu) {
5846 err = -EMSGSIZE;
5847 break;
5848 }
5849
5850 if (skb->len >= chan->sdu_len)
5851 break;
5852
5853 chan->sdu = skb;
5854 chan->sdu_last_frag = skb;
5855
5856 skb = NULL;
5857 err = 0;
5858 break;
5859
5860 case L2CAP_SAR_CONTINUE:
5861 if (!chan->sdu)
5862 break;
5863
5864 append_skb_frag(chan->sdu, skb,
5865 &chan->sdu_last_frag);
5866 skb = NULL;
5867
5868 if (chan->sdu->len >= chan->sdu_len)
5869 break;
5870
5871 err = 0;
5872 break;
5873
5874 case L2CAP_SAR_END:
5875 if (!chan->sdu)
5876 break;
5877
5878 append_skb_frag(chan->sdu, skb,
5879 &chan->sdu_last_frag);
5880 skb = NULL;
5881
5882 if (chan->sdu->len != chan->sdu_len)
5883 break;
5884
5885 err = chan->ops->recv(chan, chan->sdu);
5886
5887 if (!err) {
5888 /* Reassembly complete */
5889 chan->sdu = NULL;
5890 chan->sdu_last_frag = NULL;
5891 chan->sdu_len = 0;
5892 }
5893 break;
5894 }
5895
5896 if (err) {
5897 kfree_skb(skb);
5898 kfree_skb(chan->sdu);
5899 chan->sdu = NULL;
5900 chan->sdu_last_frag = NULL;
5901 chan->sdu_len = 0;
5902 }
5903
5904 return err;
5905}
5906
5907static int l2cap_resegment(struct l2cap_chan *chan)
5908{
5909 /* Placeholder */
5910 return 0;
5911}
5912
5913void l2cap_chan_busy(struct l2cap_chan *chan, int busy)
5914{
5915 u8 event;
5916
5917 if (chan->mode != L2CAP_MODE_ERTM)
5918 return;
5919
5920 event = busy ? L2CAP_EV_LOCAL_BUSY_DETECTED : L2CAP_EV_LOCAL_BUSY_CLEAR;
5921 l2cap_tx(chan, NULL, NULL, event);
5922}
5923
5924static int l2cap_rx_queued_iframes(struct l2cap_chan *chan)
5925{
5926 int err = 0;
5927 /* Pass sequential frames to l2cap_reassemble_sdu()
5928 * until a gap is encountered.
5929 */
5930
5931 BT_DBG("chan %p", chan);
5932
5933 while (!test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
5934 struct sk_buff *skb;
5935 BT_DBG("Searching for skb with txseq %d (queue len %d)",
5936 chan->buffer_seq, skb_queue_len(&chan->srej_q));
5937
5938 skb = l2cap_ertm_seq_in_queue(&chan->srej_q, chan->buffer_seq);
5939
5940 if (!skb)
5941 break;
5942
5943 skb_unlink(skb, &chan->srej_q);
5944 chan->buffer_seq = __next_seq(chan, chan->buffer_seq);
5945 err = l2cap_reassemble_sdu(chan, skb, &bt_cb(skb)->l2cap);
5946 if (err)
5947 break;
5948 }
5949
5950 if (skb_queue_empty(&chan->srej_q)) {
5951 chan->rx_state = L2CAP_RX_STATE_RECV;
5952 l2cap_send_ack(chan);
5953 }
5954
5955 return err;
5956}
5957
5958static void l2cap_handle_srej(struct l2cap_chan *chan,
5959 struct l2cap_ctrl *control)
5960{
5961 struct sk_buff *skb;
5962
5963 BT_DBG("chan %p, control %p", chan, control);
5964
5965 if (control->reqseq == chan->next_tx_seq) {
5966 BT_DBG("Invalid reqseq %d, disconnecting", control->reqseq);
5967 l2cap_send_disconn_req(chan, ECONNRESET);
5968 return;
5969 }
5970
5971 skb = l2cap_ertm_seq_in_queue(&chan->tx_q, control->reqseq);
5972
5973 if (skb == NULL) {
5974 BT_DBG("Seq %d not available for retransmission",
5975 control->reqseq);
5976 return;
5977 }
5978
5979 if (chan->max_tx != 0 && bt_cb(skb)->l2cap.retries >= chan->max_tx) {
5980 BT_DBG("Retry limit exceeded (%d)", chan->max_tx);
5981 l2cap_send_disconn_req(chan, ECONNRESET);
5982 return;
5983 }
5984
5985 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
5986
5987 if (control->poll) {
5988 l2cap_pass_to_tx(chan, control);
5989
5990 set_bit(CONN_SEND_FBIT, &chan->conn_state);
5991 l2cap_retransmit(chan, control);
5992 l2cap_ertm_send(chan);
5993
5994 if (chan->tx_state == L2CAP_TX_STATE_WAIT_F) {
5995 set_bit(CONN_SREJ_ACT, &chan->conn_state);
5996 chan->srej_save_reqseq = control->reqseq;
5997 }
5998 } else {
5999 l2cap_pass_to_tx_fbit(chan, control);
6000
6001 if (control->final) {
6002 if (chan->srej_save_reqseq != control->reqseq ||
6003 !test_and_clear_bit(CONN_SREJ_ACT,
6004 &chan->conn_state))
6005 l2cap_retransmit(chan, control);
6006 } else {
6007 l2cap_retransmit(chan, control);
6008 if (chan->tx_state == L2CAP_TX_STATE_WAIT_F) {
6009 set_bit(CONN_SREJ_ACT, &chan->conn_state);
6010 chan->srej_save_reqseq = control->reqseq;
6011 }
6012 }
6013 }
6014}
6015
6016static void l2cap_handle_rej(struct l2cap_chan *chan,
6017 struct l2cap_ctrl *control)
6018{
6019 struct sk_buff *skb;
6020
6021 BT_DBG("chan %p, control %p", chan, control);
6022
6023 if (control->reqseq == chan->next_tx_seq) {
6024 BT_DBG("Invalid reqseq %d, disconnecting", control->reqseq);
6025 l2cap_send_disconn_req(chan, ECONNRESET);
6026 return;
6027 }
6028
6029 skb = l2cap_ertm_seq_in_queue(&chan->tx_q, control->reqseq);
6030
6031 if (chan->max_tx && skb &&
6032 bt_cb(skb)->l2cap.retries >= chan->max_tx) {
6033 BT_DBG("Retry limit exceeded (%d)", chan->max_tx);
6034 l2cap_send_disconn_req(chan, ECONNRESET);
6035 return;
6036 }
6037
6038 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6039
6040 l2cap_pass_to_tx(chan, control);
6041
6042 if (control->final) {
6043 if (!test_and_clear_bit(CONN_REJ_ACT, &chan->conn_state))
6044 l2cap_retransmit_all(chan, control);
6045 } else {
6046 l2cap_retransmit_all(chan, control);
6047 l2cap_ertm_send(chan);
6048 if (chan->tx_state == L2CAP_TX_STATE_WAIT_F)
6049 set_bit(CONN_REJ_ACT, &chan->conn_state);
6050 }
6051}
6052
6053static u8 l2cap_classify_txseq(struct l2cap_chan *chan, u16 txseq)
6054{
6055 BT_DBG("chan %p, txseq %d", chan, txseq);
6056
6057 BT_DBG("last_acked_seq %d, expected_tx_seq %d", chan->last_acked_seq,
6058 chan->expected_tx_seq);
6059
6060 if (chan->rx_state == L2CAP_RX_STATE_SREJ_SENT) {
6061 if (__seq_offset(chan, txseq, chan->last_acked_seq) >=
6062 chan->tx_win) {
6063 /* See notes below regarding "double poll" and
6064 * invalid packets.
6065 */
6066 if (chan->tx_win <= ((chan->tx_win_max + 1) >> 1)) {
6067 BT_DBG("Invalid/Ignore - after SREJ");
6068 return L2CAP_TXSEQ_INVALID_IGNORE;
6069 } else {
6070 BT_DBG("Invalid - in window after SREJ sent");
6071 return L2CAP_TXSEQ_INVALID;
6072 }
6073 }
6074
6075 if (chan->srej_list.head == txseq) {
6076 BT_DBG("Expected SREJ");
6077 return L2CAP_TXSEQ_EXPECTED_SREJ;
6078 }
6079
6080 if (l2cap_ertm_seq_in_queue(&chan->srej_q, txseq)) {
6081 BT_DBG("Duplicate SREJ - txseq already stored");
6082 return L2CAP_TXSEQ_DUPLICATE_SREJ;
6083 }
6084
6085 if (l2cap_seq_list_contains(&chan->srej_list, txseq)) {
6086 BT_DBG("Unexpected SREJ - not requested");
6087 return L2CAP_TXSEQ_UNEXPECTED_SREJ;
6088 }
6089 }
6090
6091 if (chan->expected_tx_seq == txseq) {
6092 if (__seq_offset(chan, txseq, chan->last_acked_seq) >=
6093 chan->tx_win) {
6094 BT_DBG("Invalid - txseq outside tx window");
6095 return L2CAP_TXSEQ_INVALID;
6096 } else {
6097 BT_DBG("Expected");
6098 return L2CAP_TXSEQ_EXPECTED;
6099 }
6100 }
6101
6102 if (__seq_offset(chan, txseq, chan->last_acked_seq) <
6103 __seq_offset(chan, chan->expected_tx_seq, chan->last_acked_seq)) {
6104 BT_DBG("Duplicate - expected_tx_seq later than txseq");
6105 return L2CAP_TXSEQ_DUPLICATE;
6106 }
6107
6108 if (__seq_offset(chan, txseq, chan->last_acked_seq) >= chan->tx_win) {
6109 /* A source of invalid packets is a "double poll" condition,
6110 * where delays cause us to send multiple poll packets. If
6111 * the remote stack receives and processes both polls,
6112 * sequence numbers can wrap around in such a way that a
6113 * resent frame has a sequence number that looks like new data
6114 * with a sequence gap. This would trigger an erroneous SREJ
6115 * request.
6116 *
6117 * Fortunately, this is impossible with a tx window that's
6118 * less than half of the maximum sequence number, which allows
6119 * invalid frames to be safely ignored.
6120 *
6121 * With tx window sizes greater than half of the tx window
6122 * maximum, the frame is invalid and cannot be ignored. This
6123 * causes a disconnect.
6124 */
6125
6126 if (chan->tx_win <= ((chan->tx_win_max + 1) >> 1)) {
6127 BT_DBG("Invalid/Ignore - txseq outside tx window");
6128 return L2CAP_TXSEQ_INVALID_IGNORE;
6129 } else {
6130 BT_DBG("Invalid - txseq outside tx window");
6131 return L2CAP_TXSEQ_INVALID;
6132 }
6133 } else {
6134 BT_DBG("Unexpected - txseq indicates missing frames");
6135 return L2CAP_TXSEQ_UNEXPECTED;
6136 }
6137}
6138
6139static int l2cap_rx_state_recv(struct l2cap_chan *chan,
6140 struct l2cap_ctrl *control,
6141 struct sk_buff *skb, u8 event)
6142{
6143 int err = 0;
6144 bool skb_in_use = false;
6145
6146 BT_DBG("chan %p, control %p, skb %p, event %d", chan, control, skb,
6147 event);
6148
6149 switch (event) {
6150 case L2CAP_EV_RECV_IFRAME:
6151 switch (l2cap_classify_txseq(chan, control->txseq)) {
6152 case L2CAP_TXSEQ_EXPECTED:
6153 l2cap_pass_to_tx(chan, control);
6154
6155 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
6156 BT_DBG("Busy, discarding expected seq %d",
6157 control->txseq);
6158 break;
6159 }
6160
6161 chan->expected_tx_seq = __next_seq(chan,
6162 control->txseq);
6163
6164 chan->buffer_seq = chan->expected_tx_seq;
6165 skb_in_use = true;
6166
6167 err = l2cap_reassemble_sdu(chan, skb, control);
6168 if (err)
6169 break;
6170
6171 if (control->final) {
6172 if (!test_and_clear_bit(CONN_REJ_ACT,
6173 &chan->conn_state)) {
6174 control->final = 0;
6175 l2cap_retransmit_all(chan, control);
6176 l2cap_ertm_send(chan);
6177 }
6178 }
6179
6180 if (!test_bit(CONN_LOCAL_BUSY, &chan->conn_state))
6181 l2cap_send_ack(chan);
6182 break;
6183 case L2CAP_TXSEQ_UNEXPECTED:
6184 l2cap_pass_to_tx(chan, control);
6185
6186 /* Can't issue SREJ frames in the local busy state.
6187 * Drop this frame, it will be seen as missing
6188 * when local busy is exited.
6189 */
6190 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
6191 BT_DBG("Busy, discarding unexpected seq %d",
6192 control->txseq);
6193 break;
6194 }
6195
6196 /* There was a gap in the sequence, so an SREJ
6197 * must be sent for each missing frame. The
6198 * current frame is stored for later use.
6199 */
6200 skb_queue_tail(&chan->srej_q, skb);
6201 skb_in_use = true;
6202 BT_DBG("Queued %p (queue len %d)", skb,
6203 skb_queue_len(&chan->srej_q));
6204
6205 clear_bit(CONN_SREJ_ACT, &chan->conn_state);
6206 l2cap_seq_list_clear(&chan->srej_list);
6207 l2cap_send_srej(chan, control->txseq);
6208
6209 chan->rx_state = L2CAP_RX_STATE_SREJ_SENT;
6210 break;
6211 case L2CAP_TXSEQ_DUPLICATE:
6212 l2cap_pass_to_tx(chan, control);
6213 break;
6214 case L2CAP_TXSEQ_INVALID_IGNORE:
6215 break;
6216 case L2CAP_TXSEQ_INVALID:
6217 default:
6218 l2cap_send_disconn_req(chan, ECONNRESET);
6219 break;
6220 }
6221 break;
6222 case L2CAP_EV_RECV_RR:
6223 l2cap_pass_to_tx(chan, control);
6224 if (control->final) {
6225 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6226
6227 if (!test_and_clear_bit(CONN_REJ_ACT, &chan->conn_state) &&
6228 !__chan_is_moving(chan)) {
6229 control->final = 0;
6230 l2cap_retransmit_all(chan, control);
6231 }
6232
6233 l2cap_ertm_send(chan);
6234 } else if (control->poll) {
6235 l2cap_send_i_or_rr_or_rnr(chan);
6236 } else {
6237 if (test_and_clear_bit(CONN_REMOTE_BUSY,
6238 &chan->conn_state) &&
6239 chan->unacked_frames)
6240 __set_retrans_timer(chan);
6241
6242 l2cap_ertm_send(chan);
6243 }
6244 break;
6245 case L2CAP_EV_RECV_RNR:
6246 set_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6247 l2cap_pass_to_tx(chan, control);
6248 if (control && control->poll) {
6249 set_bit(CONN_SEND_FBIT, &chan->conn_state);
6250 l2cap_send_rr_or_rnr(chan, 0);
6251 }
6252 __clear_retrans_timer(chan);
6253 l2cap_seq_list_clear(&chan->retrans_list);
6254 break;
6255 case L2CAP_EV_RECV_REJ:
6256 l2cap_handle_rej(chan, control);
6257 break;
6258 case L2CAP_EV_RECV_SREJ:
6259 l2cap_handle_srej(chan, control);
6260 break;
6261 default:
6262 break;
6263 }
6264
6265 if (skb && !skb_in_use) {
6266 BT_DBG("Freeing %p", skb);
6267 kfree_skb(skb);
6268 }
6269
6270 return err;
6271}
6272
6273static int l2cap_rx_state_srej_sent(struct l2cap_chan *chan,
6274 struct l2cap_ctrl *control,
6275 struct sk_buff *skb, u8 event)
6276{
6277 int err = 0;
6278 u16 txseq = control->txseq;
6279 bool skb_in_use = false;
6280
6281 BT_DBG("chan %p, control %p, skb %p, event %d", chan, control, skb,
6282 event);
6283
6284 switch (event) {
6285 case L2CAP_EV_RECV_IFRAME:
6286 switch (l2cap_classify_txseq(chan, txseq)) {
6287 case L2CAP_TXSEQ_EXPECTED:
6288 /* Keep frame for reassembly later */
6289 l2cap_pass_to_tx(chan, control);
6290 skb_queue_tail(&chan->srej_q, skb);
6291 skb_in_use = true;
6292 BT_DBG("Queued %p (queue len %d)", skb,
6293 skb_queue_len(&chan->srej_q));
6294
6295 chan->expected_tx_seq = __next_seq(chan, txseq);
6296 break;
6297 case L2CAP_TXSEQ_EXPECTED_SREJ:
6298 l2cap_seq_list_pop(&chan->srej_list);
6299
6300 l2cap_pass_to_tx(chan, control);
6301 skb_queue_tail(&chan->srej_q, skb);
6302 skb_in_use = true;
6303 BT_DBG("Queued %p (queue len %d)", skb,
6304 skb_queue_len(&chan->srej_q));
6305
6306 err = l2cap_rx_queued_iframes(chan);
6307 if (err)
6308 break;
6309
6310 break;
6311 case L2CAP_TXSEQ_UNEXPECTED:
6312 /* Got a frame that can't be reassembled yet.
6313 * Save it for later, and send SREJs to cover
6314 * the missing frames.
6315 */
6316 skb_queue_tail(&chan->srej_q, skb);
6317 skb_in_use = true;
6318 BT_DBG("Queued %p (queue len %d)", skb,
6319 skb_queue_len(&chan->srej_q));
6320
6321 l2cap_pass_to_tx(chan, control);
6322 l2cap_send_srej(chan, control->txseq);
6323 break;
6324 case L2CAP_TXSEQ_UNEXPECTED_SREJ:
6325 /* This frame was requested with an SREJ, but
6326 * some expected retransmitted frames are
6327 * missing. Request retransmission of missing
6328 * SREJ'd frames.
6329 */
6330 skb_queue_tail(&chan->srej_q, skb);
6331 skb_in_use = true;
6332 BT_DBG("Queued %p (queue len %d)", skb,
6333 skb_queue_len(&chan->srej_q));
6334
6335 l2cap_pass_to_tx(chan, control);
6336 l2cap_send_srej_list(chan, control->txseq);
6337 break;
6338 case L2CAP_TXSEQ_DUPLICATE_SREJ:
6339 /* We've already queued this frame. Drop this copy. */
6340 l2cap_pass_to_tx(chan, control);
6341 break;
6342 case L2CAP_TXSEQ_DUPLICATE:
6343 /* Expecting a later sequence number, so this frame
6344 * was already received. Ignore it completely.
6345 */
6346 break;
6347 case L2CAP_TXSEQ_INVALID_IGNORE:
6348 break;
6349 case L2CAP_TXSEQ_INVALID:
6350 default:
6351 l2cap_send_disconn_req(chan, ECONNRESET);
6352 break;
6353 }
6354 break;
6355 case L2CAP_EV_RECV_RR:
6356 l2cap_pass_to_tx(chan, control);
6357 if (control->final) {
6358 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6359
6360 if (!test_and_clear_bit(CONN_REJ_ACT,
6361 &chan->conn_state)) {
6362 control->final = 0;
6363 l2cap_retransmit_all(chan, control);
6364 }
6365
6366 l2cap_ertm_send(chan);
6367 } else if (control->poll) {
6368 if (test_and_clear_bit(CONN_REMOTE_BUSY,
6369 &chan->conn_state) &&
6370 chan->unacked_frames) {
6371 __set_retrans_timer(chan);
6372 }
6373
6374 set_bit(CONN_SEND_FBIT, &chan->conn_state);
6375 l2cap_send_srej_tail(chan);
6376 } else {
6377 if (test_and_clear_bit(CONN_REMOTE_BUSY,
6378 &chan->conn_state) &&
6379 chan->unacked_frames)
6380 __set_retrans_timer(chan);
6381
6382 l2cap_send_ack(chan);
6383 }
6384 break;
6385 case L2CAP_EV_RECV_RNR:
6386 set_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6387 l2cap_pass_to_tx(chan, control);
6388 if (control->poll) {
6389 l2cap_send_srej_tail(chan);
6390 } else {
6391 struct l2cap_ctrl rr_control;
6392 memset(&rr_control, 0, sizeof(rr_control));
6393 rr_control.sframe = 1;
6394 rr_control.super = L2CAP_SUPER_RR;
6395 rr_control.reqseq = chan->buffer_seq;
6396 l2cap_send_sframe(chan, &rr_control);
6397 }
6398
6399 break;
6400 case L2CAP_EV_RECV_REJ:
6401 l2cap_handle_rej(chan, control);
6402 break;
6403 case L2CAP_EV_RECV_SREJ:
6404 l2cap_handle_srej(chan, control);
6405 break;
6406 }
6407
6408 if (skb && !skb_in_use) {
6409 BT_DBG("Freeing %p", skb);
6410 kfree_skb(skb);
6411 }
6412
6413 return err;
6414}
6415
6416static int l2cap_finish_move(struct l2cap_chan *chan)
6417{
6418 BT_DBG("chan %p", chan);
6419
6420 chan->rx_state = L2CAP_RX_STATE_RECV;
6421
6422 if (chan->hs_hcon)
6423 chan->conn->mtu = chan->hs_hcon->hdev->block_mtu;
6424 else
6425 chan->conn->mtu = chan->conn->hcon->hdev->acl_mtu;
6426
6427 return l2cap_resegment(chan);
6428}
6429
6430static int l2cap_rx_state_wait_p(struct l2cap_chan *chan,
6431 struct l2cap_ctrl *control,
6432 struct sk_buff *skb, u8 event)
6433{
6434 int err;
6435
6436 BT_DBG("chan %p, control %p, skb %p, event %d", chan, control, skb,
6437 event);
6438
6439 if (!control->poll)
6440 return -EPROTO;
6441
6442 l2cap_process_reqseq(chan, control->reqseq);
6443
6444 if (!skb_queue_empty(&chan->tx_q))
6445 chan->tx_send_head = skb_peek(&chan->tx_q);
6446 else
6447 chan->tx_send_head = NULL;
6448
6449 /* Rewind next_tx_seq to the point expected
6450 * by the receiver.
6451 */
6452 chan->next_tx_seq = control->reqseq;
6453 chan->unacked_frames = 0;
6454
6455 err = l2cap_finish_move(chan);
6456 if (err)
6457 return err;
6458
6459 set_bit(CONN_SEND_FBIT, &chan->conn_state);
6460 l2cap_send_i_or_rr_or_rnr(chan);
6461
6462 if (event == L2CAP_EV_RECV_IFRAME)
6463 return -EPROTO;
6464
6465 return l2cap_rx_state_recv(chan, control, NULL, event);
6466}
6467
6468static int l2cap_rx_state_wait_f(struct l2cap_chan *chan,
6469 struct l2cap_ctrl *control,
6470 struct sk_buff *skb, u8 event)
6471{
6472 int err;
6473
6474 if (!control->final)
6475 return -EPROTO;
6476
6477 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6478
6479 chan->rx_state = L2CAP_RX_STATE_RECV;
6480 l2cap_process_reqseq(chan, control->reqseq);
6481
6482 if (!skb_queue_empty(&chan->tx_q))
6483 chan->tx_send_head = skb_peek(&chan->tx_q);
6484 else
6485 chan->tx_send_head = NULL;
6486
6487 /* Rewind next_tx_seq to the point expected
6488 * by the receiver.
6489 */
6490 chan->next_tx_seq = control->reqseq;
6491 chan->unacked_frames = 0;
6492
6493 if (chan->hs_hcon)
6494 chan->conn->mtu = chan->hs_hcon->hdev->block_mtu;
6495 else
6496 chan->conn->mtu = chan->conn->hcon->hdev->acl_mtu;
6497
6498 err = l2cap_resegment(chan);
6499
6500 if (!err)
6501 err = l2cap_rx_state_recv(chan, control, skb, event);
6502
6503 return err;
6504}
6505
6506static bool __valid_reqseq(struct l2cap_chan *chan, u16 reqseq)
6507{
6508 /* Make sure reqseq is for a packet that has been sent but not acked */
6509 u16 unacked;
6510
6511 unacked = __seq_offset(chan, chan->next_tx_seq, chan->expected_ack_seq);
6512 return __seq_offset(chan, chan->next_tx_seq, reqseq) <= unacked;
6513}
6514
6515static int l2cap_rx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
6516 struct sk_buff *skb, u8 event)
6517{
6518 int err = 0;
6519
6520 BT_DBG("chan %p, control %p, skb %p, event %d, state %d", chan,
6521 control, skb, event, chan->rx_state);
6522
6523 if (__valid_reqseq(chan, control->reqseq)) {
6524 switch (chan->rx_state) {
6525 case L2CAP_RX_STATE_RECV:
6526 err = l2cap_rx_state_recv(chan, control, skb, event);
6527 break;
6528 case L2CAP_RX_STATE_SREJ_SENT:
6529 err = l2cap_rx_state_srej_sent(chan, control, skb,
6530 event);
6531 break;
6532 case L2CAP_RX_STATE_WAIT_P:
6533 err = l2cap_rx_state_wait_p(chan, control, skb, event);
6534 break;
6535 case L2CAP_RX_STATE_WAIT_F:
6536 err = l2cap_rx_state_wait_f(chan, control, skb, event);
6537 break;
6538 default:
6539 /* shut it down */
6540 break;
6541 }
6542 } else {
6543 BT_DBG("Invalid reqseq %d (next_tx_seq %d, expected_ack_seq %d",
6544 control->reqseq, chan->next_tx_seq,
6545 chan->expected_ack_seq);
6546 l2cap_send_disconn_req(chan, ECONNRESET);
6547 }
6548
6549 return err;
6550}
6551
6552static int l2cap_stream_rx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
6553 struct sk_buff *skb)
6554{
6555 BT_DBG("chan %p, control %p, skb %p, state %d", chan, control, skb,
6556 chan->rx_state);
6557
6558 if (l2cap_classify_txseq(chan, control->txseq) ==
6559 L2CAP_TXSEQ_EXPECTED) {
6560 l2cap_pass_to_tx(chan, control);
6561
6562 BT_DBG("buffer_seq %d->%d", chan->buffer_seq,
6563 __next_seq(chan, chan->buffer_seq));
6564
6565 chan->buffer_seq = __next_seq(chan, chan->buffer_seq);
6566
6567 l2cap_reassemble_sdu(chan, skb, control);
6568 } else {
6569 if (chan->sdu) {
6570 kfree_skb(chan->sdu);
6571 chan->sdu = NULL;
6572 }
6573 chan->sdu_last_frag = NULL;
6574 chan->sdu_len = 0;
6575
6576 if (skb) {
6577 BT_DBG("Freeing %p", skb);
6578 kfree_skb(skb);
6579 }
6580 }
6581
6582 chan->last_acked_seq = control->txseq;
6583 chan->expected_tx_seq = __next_seq(chan, control->txseq);
6584
6585 return 0;
6586}
6587
6588static int l2cap_data_rcv(struct l2cap_chan *chan, struct sk_buff *skb)
6589{
6590 struct l2cap_ctrl *control = &bt_cb(skb)->l2cap;
6591 u16 len;
6592 u8 event;
6593
6594 __unpack_control(chan, skb);
6595
6596 len = skb->len;
6597
6598 /*
6599 * We can just drop the corrupted I-frame here.
6600 * Receiver will miss it and start proper recovery
6601 * procedures and ask for retransmission.
6602 */
6603 if (l2cap_check_fcs(chan, skb))
6604 goto drop;
6605
6606 if (!control->sframe && control->sar == L2CAP_SAR_START)
6607 len -= L2CAP_SDULEN_SIZE;
6608
6609 if (chan->fcs == L2CAP_FCS_CRC16)
6610 len -= L2CAP_FCS_SIZE;
6611
6612 if (len > chan->mps) {
6613 l2cap_send_disconn_req(chan, ECONNRESET);
6614 goto drop;
6615 }
6616
6617 if ((chan->mode == L2CAP_MODE_ERTM ||
6618 chan->mode == L2CAP_MODE_STREAMING) && sk_filter(chan->data, skb))
6619 goto drop;
6620
6621 if (!control->sframe) {
6622 int err;
6623
6624 BT_DBG("iframe sar %d, reqseq %d, final %d, txseq %d",
6625 control->sar, control->reqseq, control->final,
6626 control->txseq);
6627
6628 /* Validate F-bit - F=0 always valid, F=1 only
6629 * valid in TX WAIT_F
6630 */
6631 if (control->final && chan->tx_state != L2CAP_TX_STATE_WAIT_F)
6632 goto drop;
6633
6634 if (chan->mode != L2CAP_MODE_STREAMING) {
6635 event = L2CAP_EV_RECV_IFRAME;
6636 err = l2cap_rx(chan, control, skb, event);
6637 } else {
6638 err = l2cap_stream_rx(chan, control, skb);
6639 }
6640
6641 if (err)
6642 l2cap_send_disconn_req(chan, ECONNRESET);
6643 } else {
6644 const u8 rx_func_to_event[4] = {
6645 L2CAP_EV_RECV_RR, L2CAP_EV_RECV_REJ,
6646 L2CAP_EV_RECV_RNR, L2CAP_EV_RECV_SREJ
6647 };
6648
6649 /* Only I-frames are expected in streaming mode */
6650 if (chan->mode == L2CAP_MODE_STREAMING)
6651 goto drop;
6652
6653 BT_DBG("sframe reqseq %d, final %d, poll %d, super %d",
6654 control->reqseq, control->final, control->poll,
6655 control->super);
6656
6657 if (len != 0) {
6658 BT_ERR("Trailing bytes: %d in sframe", len);
6659 l2cap_send_disconn_req(chan, ECONNRESET);
6660 goto drop;
6661 }
6662
6663 /* Validate F and P bits */
6664 if (control->final && (control->poll ||
6665 chan->tx_state != L2CAP_TX_STATE_WAIT_F))
6666 goto drop;
6667
6668 event = rx_func_to_event[control->super];
6669 if (l2cap_rx(chan, control, skb, event))
6670 l2cap_send_disconn_req(chan, ECONNRESET);
6671 }
6672
6673 return 0;
6674
6675drop:
6676 kfree_skb(skb);
6677 return 0;
6678}
6679
6680static void l2cap_chan_le_send_credits(struct l2cap_chan *chan)
6681{
6682 struct l2cap_conn *conn = chan->conn;
6683 struct l2cap_le_credits pkt;
6684 u16 return_credits;
6685
6686 /* We return more credits to the sender only after the amount of
6687 * credits falls below half of the initial amount.
6688 */
6689 if (chan->rx_credits >= (le_max_credits + 1) / 2)
6690 return;
6691
6692 return_credits = le_max_credits - chan->rx_credits;
6693
6694 BT_DBG("chan %p returning %u credits to sender", chan, return_credits);
6695
6696 chan->rx_credits += return_credits;
6697
6698 pkt.cid = cpu_to_le16(chan->scid);
6699 pkt.credits = cpu_to_le16(return_credits);
6700
6701 chan->ident = l2cap_get_ident(conn);
6702
6703 l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CREDITS, sizeof(pkt), &pkt);
6704}
6705
6706static int l2cap_le_data_rcv(struct l2cap_chan *chan, struct sk_buff *skb)
6707{
6708 int err;
6709
6710 if (!chan->rx_credits) {
6711 BT_ERR("No credits to receive LE L2CAP data");
6712 l2cap_send_disconn_req(chan, ECONNRESET);
6713 return -ENOBUFS;
6714 }
6715
6716 if (chan->imtu < skb->len) {
6717 BT_ERR("Too big LE L2CAP PDU");
6718 return -ENOBUFS;
6719 }
6720
6721 chan->rx_credits--;
6722 BT_DBG("rx_credits %u -> %u", chan->rx_credits + 1, chan->rx_credits);
6723
6724 l2cap_chan_le_send_credits(chan);
6725
6726 err = 0;
6727
6728 if (!chan->sdu) {
6729 u16 sdu_len;
6730
6731 sdu_len = get_unaligned_le16(skb->data);
6732 skb_pull(skb, L2CAP_SDULEN_SIZE);
6733
6734 BT_DBG("Start of new SDU. sdu_len %u skb->len %u imtu %u",
6735 sdu_len, skb->len, chan->imtu);
6736
6737 if (sdu_len > chan->imtu) {
6738 BT_ERR("Too big LE L2CAP SDU length received");
6739 err = -EMSGSIZE;
6740 goto failed;
6741 }
6742
6743 if (skb->len > sdu_len) {
6744 BT_ERR("Too much LE L2CAP data received");
6745 err = -EINVAL;
6746 goto failed;
6747 }
6748
6749 if (skb->len == sdu_len)
6750 return chan->ops->recv(chan, skb);
6751
6752 chan->sdu = skb;
6753 chan->sdu_len = sdu_len;
6754 chan->sdu_last_frag = skb;
6755
6756 return 0;
6757 }
6758
6759 BT_DBG("SDU fragment. chan->sdu->len %u skb->len %u chan->sdu_len %u",
6760 chan->sdu->len, skb->len, chan->sdu_len);
6761
6762 if (chan->sdu->len + skb->len > chan->sdu_len) {
6763 BT_ERR("Too much LE L2CAP data received");
6764 err = -EINVAL;
6765 goto failed;
6766 }
6767
6768 append_skb_frag(chan->sdu, skb, &chan->sdu_last_frag);
6769 skb = NULL;
6770
6771 if (chan->sdu->len == chan->sdu_len) {
6772 err = chan->ops->recv(chan, chan->sdu);
6773 if (!err) {
6774 chan->sdu = NULL;
6775 chan->sdu_last_frag = NULL;
6776 chan->sdu_len = 0;
6777 }
6778 }
6779
6780failed:
6781 if (err) {
6782 kfree_skb(skb);
6783 kfree_skb(chan->sdu);
6784 chan->sdu = NULL;
6785 chan->sdu_last_frag = NULL;
6786 chan->sdu_len = 0;
6787 }
6788
6789 /* We can't return an error here since we took care of the skb
6790 * freeing internally. An error return would cause the caller to
6791 * do a double-free of the skb.
6792 */
6793 return 0;
6794}
6795
6796static void l2cap_data_channel(struct l2cap_conn *conn, u16 cid,
6797 struct sk_buff *skb)
6798{
6799 struct l2cap_chan *chan;
6800
6801 chan = l2cap_get_chan_by_scid(conn, cid);
6802 if (!chan) {
6803 if (cid == L2CAP_CID_A2MP) {
6804 chan = a2mp_channel_create(conn, skb);
6805 if (!chan) {
6806 kfree_skb(skb);
6807 return;
6808 }
6809
6810 l2cap_chan_lock(chan);
6811 } else {
6812 BT_DBG("unknown cid 0x%4.4x", cid);
6813 /* Drop packet and return */
6814 kfree_skb(skb);
6815 return;
6816 }
6817 }
6818
6819 BT_DBG("chan %p, len %d", chan, skb->len);
6820
6821 /* If we receive data on a fixed channel before the info req/rsp
6822 * procdure is done simply assume that the channel is supported
6823 * and mark it as ready.
6824 */
6825 if (chan->chan_type == L2CAP_CHAN_FIXED)
6826 l2cap_chan_ready(chan);
6827
6828 if (chan->state != BT_CONNECTED)
6829 goto drop;
6830
6831 switch (chan->mode) {
6832 case L2CAP_MODE_LE_FLOWCTL:
6833 if (l2cap_le_data_rcv(chan, skb) < 0)
6834 goto drop;
6835
6836 goto done;
6837
6838 case L2CAP_MODE_BASIC:
6839 /* If socket recv buffers overflows we drop data here
6840 * which is *bad* because L2CAP has to be reliable.
6841 * But we don't have any other choice. L2CAP doesn't
6842 * provide flow control mechanism. */
6843
6844 if (chan->imtu < skb->len) {
6845 BT_ERR("Dropping L2CAP data: receive buffer overflow");
6846 goto drop;
6847 }
6848
6849 if (!chan->ops->recv(chan, skb))
6850 goto done;
6851 break;
6852
6853 case L2CAP_MODE_ERTM:
6854 case L2CAP_MODE_STREAMING:
6855 l2cap_data_rcv(chan, skb);
6856 goto done;
6857
6858 default:
6859 BT_DBG("chan %p: bad mode 0x%2.2x", chan, chan->mode);
6860 break;
6861 }
6862
6863drop:
6864 kfree_skb(skb);
6865
6866done:
6867 l2cap_chan_unlock(chan);
6868}
6869
6870static void l2cap_conless_channel(struct l2cap_conn *conn, __le16 psm,
6871 struct sk_buff *skb)
6872{
6873 struct hci_conn *hcon = conn->hcon;
6874 struct l2cap_chan *chan;
6875
6876 if (hcon->type != ACL_LINK)
6877 goto free_skb;
6878
6879 chan = l2cap_global_chan_by_psm(0, psm, &hcon->src, &hcon->dst,
6880 ACL_LINK);
6881 if (!chan)
6882 goto free_skb;
6883
6884 BT_DBG("chan %p, len %d", chan, skb->len);
6885
6886 if (chan->state != BT_BOUND && chan->state != BT_CONNECTED)
6887 goto drop;
6888
6889 if (chan->imtu < skb->len)
6890 goto drop;
6891
6892 /* Store remote BD_ADDR and PSM for msg_name */
6893 bacpy(&bt_cb(skb)->l2cap.bdaddr, &hcon->dst);
6894 bt_cb(skb)->l2cap.psm = psm;
6895
6896 if (!chan->ops->recv(chan, skb)) {
6897 l2cap_chan_put(chan);
6898 return;
6899 }
6900
6901drop:
6902 l2cap_chan_put(chan);
6903free_skb:
6904 kfree_skb(skb);
6905}
6906
6907static void l2cap_recv_frame(struct l2cap_conn *conn, struct sk_buff *skb)
6908{
6909 struct l2cap_hdr *lh = (void *) skb->data;
6910 struct hci_conn *hcon = conn->hcon;
6911 u16 cid, len;
6912 __le16 psm;
6913
6914 if (hcon->state != BT_CONNECTED) {
6915 BT_DBG("queueing pending rx skb");
6916 skb_queue_tail(&conn->pending_rx, skb);
6917 return;
6918 }
6919
6920 skb_pull(skb, L2CAP_HDR_SIZE);
6921 cid = __le16_to_cpu(lh->cid);
6922 len = __le16_to_cpu(lh->len);
6923
6924 if (len != skb->len) {
6925 kfree_skb(skb);
6926 return;
6927 }
6928
6929 /* Since we can't actively block incoming LE connections we must
6930 * at least ensure that we ignore incoming data from them.
6931 */
6932 if (hcon->type == LE_LINK &&
6933 hci_bdaddr_list_lookup(&hcon->hdev->blacklist, &hcon->dst,
6934 bdaddr_dst_type(hcon))) {
6935 kfree_skb(skb);
6936 return;
6937 }
6938
6939 BT_DBG("len %d, cid 0x%4.4x", len, cid);
6940
6941 switch (cid) {
6942 case L2CAP_CID_SIGNALING:
6943 l2cap_sig_channel(conn, skb);
6944 break;
6945
6946 case L2CAP_CID_CONN_LESS:
6947 psm = get_unaligned((__le16 *) skb->data);
6948 skb_pull(skb, L2CAP_PSMLEN_SIZE);
6949 l2cap_conless_channel(conn, psm, skb);
6950 break;
6951
6952 case L2CAP_CID_LE_SIGNALING:
6953 l2cap_le_sig_channel(conn, skb);
6954 break;
6955
6956 default:
6957 l2cap_data_channel(conn, cid, skb);
6958 break;
6959 }
6960}
6961
6962static void process_pending_rx(struct work_struct *work)
6963{
6964 struct l2cap_conn *conn = container_of(work, struct l2cap_conn,
6965 pending_rx_work);
6966 struct sk_buff *skb;
6967
6968 BT_DBG("");
6969
6970 while ((skb = skb_dequeue(&conn->pending_rx)))
6971 l2cap_recv_frame(conn, skb);
6972}
6973
6974static struct l2cap_conn *l2cap_conn_add(struct hci_conn *hcon)
6975{
6976 struct l2cap_conn *conn = hcon->l2cap_data;
6977 struct hci_chan *hchan;
6978
6979 if (conn)
6980 return conn;
6981
6982 hchan = hci_chan_create(hcon);
6983 if (!hchan)
6984 return NULL;
6985
6986 conn = kzalloc(sizeof(*conn), GFP_KERNEL);
6987 if (!conn) {
6988 hci_chan_del(hchan);
6989 return NULL;
6990 }
6991
6992 kref_init(&conn->ref);
6993 hcon->l2cap_data = conn;
6994 conn->hcon = hci_conn_get(hcon);
6995 conn->hchan = hchan;
6996
6997 BT_DBG("hcon %p conn %p hchan %p", hcon, conn, hchan);
6998
6999 switch (hcon->type) {
7000 case LE_LINK:
7001 if (hcon->hdev->le_mtu) {
7002 conn->mtu = hcon->hdev->le_mtu;
7003 break;
7004 }
7005 /* fall through */
7006 default:
7007 conn->mtu = hcon->hdev->acl_mtu;
7008 break;
7009 }
7010
7011 conn->feat_mask = 0;
7012
7013 conn->local_fixed_chan = L2CAP_FC_SIG_BREDR | L2CAP_FC_CONNLESS;
7014
7015 if (hcon->type == ACL_LINK &&
7016 hci_dev_test_flag(hcon->hdev, HCI_HS_ENABLED))
7017 conn->local_fixed_chan |= L2CAP_FC_A2MP;
7018
7019 if (hci_dev_test_flag(hcon->hdev, HCI_LE_ENABLED) &&
7020 (bredr_sc_enabled(hcon->hdev) ||
7021 hci_dev_test_flag(hcon->hdev, HCI_FORCE_BREDR_SMP)))
7022 conn->local_fixed_chan |= L2CAP_FC_SMP_BREDR;
7023
7024 mutex_init(&conn->ident_lock);
7025 mutex_init(&conn->chan_lock);
7026
7027 INIT_LIST_HEAD(&conn->chan_l);
7028 INIT_LIST_HEAD(&conn->users);
7029
7030 INIT_DELAYED_WORK(&conn->info_timer, l2cap_info_timeout);
7031
7032 skb_queue_head_init(&conn->pending_rx);
7033 INIT_WORK(&conn->pending_rx_work, process_pending_rx);
7034 INIT_WORK(&conn->id_addr_update_work, l2cap_conn_update_id_addr);
7035
7036 conn->disc_reason = HCI_ERROR_REMOTE_USER_TERM;
7037
7038 return conn;
7039}
7040
7041static bool is_valid_psm(u16 psm, u8 dst_type) {
7042 if (!psm)
7043 return false;
7044
7045 if (bdaddr_type_is_le(dst_type))
7046 return (psm <= 0x00ff);
7047
7048 /* PSM must be odd and lsb of upper byte must be 0 */
7049 return ((psm & 0x0101) == 0x0001);
7050}
7051
7052int l2cap_chan_connect(struct l2cap_chan *chan, __le16 psm, u16 cid,
7053 bdaddr_t *dst, u8 dst_type)
7054{
7055 struct l2cap_conn *conn;
7056 struct hci_conn *hcon;
7057 struct hci_dev *hdev;
7058 int err;
7059
7060 BT_DBG("%pMR -> %pMR (type %u) psm 0x%2.2x", &chan->src, dst,
7061 dst_type, __le16_to_cpu(psm));
7062
7063 hdev = hci_get_route(dst, &chan->src, chan->src_type);
7064 if (!hdev)
7065 return -EHOSTUNREACH;
7066
7067 hci_dev_lock(hdev);
7068
7069 if (!is_valid_psm(__le16_to_cpu(psm), dst_type) && !cid &&
7070 chan->chan_type != L2CAP_CHAN_RAW) {
7071 err = -EINVAL;
7072 goto done;
7073 }
7074
7075 if (chan->chan_type == L2CAP_CHAN_CONN_ORIENTED && !psm) {
7076 err = -EINVAL;
7077 goto done;
7078 }
7079
7080 if (chan->chan_type == L2CAP_CHAN_FIXED && !cid) {
7081 err = -EINVAL;
7082 goto done;
7083 }
7084
7085 switch (chan->mode) {
7086 case L2CAP_MODE_BASIC:
7087 break;
7088 case L2CAP_MODE_LE_FLOWCTL:
7089 l2cap_le_flowctl_init(chan);
7090 break;
7091 case L2CAP_MODE_ERTM:
7092 case L2CAP_MODE_STREAMING:
7093 if (!disable_ertm)
7094 break;
7095 /* fall through */
7096 default:
7097 err = -EOPNOTSUPP;
7098 goto done;
7099 }
7100
7101 switch (chan->state) {
7102 case BT_CONNECT:
7103 case BT_CONNECT2:
7104 case BT_CONFIG:
7105 /* Already connecting */
7106 err = 0;
7107 goto done;
7108
7109 case BT_CONNECTED:
7110 /* Already connected */
7111 err = -EISCONN;
7112 goto done;
7113
7114 case BT_OPEN:
7115 case BT_BOUND:
7116 /* Can connect */
7117 break;
7118
7119 default:
7120 err = -EBADFD;
7121 goto done;
7122 }
7123
7124 /* Set destination address and psm */
7125 bacpy(&chan->dst, dst);
7126 chan->dst_type = dst_type;
7127
7128 chan->psm = psm;
7129 chan->dcid = cid;
7130
7131 if (bdaddr_type_is_le(dst_type)) {
7132 /* Convert from L2CAP channel address type to HCI address type
7133 */
7134 if (dst_type == BDADDR_LE_PUBLIC)
7135 dst_type = ADDR_LE_DEV_PUBLIC;
7136 else
7137 dst_type = ADDR_LE_DEV_RANDOM;
7138
7139 if (hci_dev_test_flag(hdev, HCI_ADVERTISING))
7140 hcon = hci_connect_le(hdev, dst, dst_type,
7141 chan->sec_level,
7142 HCI_LE_CONN_TIMEOUT,
7143 HCI_ROLE_SLAVE);
7144 else
7145 hcon = hci_connect_le_scan(hdev, dst, dst_type,
7146 chan->sec_level,
7147 HCI_LE_CONN_TIMEOUT);
7148
7149 } else {
7150 u8 auth_type = l2cap_get_auth_type(chan);
7151 hcon = hci_connect_acl(hdev, dst, chan->sec_level, auth_type);
7152 }
7153
7154 if (IS_ERR(hcon)) {
7155 err = PTR_ERR(hcon);
7156 goto done;
7157 }
7158
7159 conn = l2cap_conn_add(hcon);
7160 if (!conn) {
7161 hci_conn_drop(hcon);
7162 err = -ENOMEM;
7163 goto done;
7164 }
7165
7166 mutex_lock(&conn->chan_lock);
7167 l2cap_chan_lock(chan);
7168
7169 if (cid && __l2cap_get_chan_by_dcid(conn, cid)) {
7170 hci_conn_drop(hcon);
7171 err = -EBUSY;
7172 goto chan_unlock;
7173 }
7174
7175 /* Update source addr of the socket */
7176 bacpy(&chan->src, &hcon->src);
7177 chan->src_type = bdaddr_src_type(hcon);
7178
7179 __l2cap_chan_add(conn, chan);
7180
7181 /* l2cap_chan_add takes its own ref so we can drop this one */
7182 hci_conn_drop(hcon);
7183
7184 l2cap_state_change(chan, BT_CONNECT);
7185 __set_chan_timer(chan, chan->ops->get_sndtimeo(chan));
7186
7187 /* Release chan->sport so that it can be reused by other
7188 * sockets (as it's only used for listening sockets).
7189 */
7190 write_lock(&chan_list_lock);
7191 chan->sport = 0;
7192 write_unlock(&chan_list_lock);
7193
7194 if (hcon->state == BT_CONNECTED) {
7195 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) {
7196 __clear_chan_timer(chan);
7197 if (l2cap_chan_check_security(chan, true))
7198 l2cap_state_change(chan, BT_CONNECTED);
7199 } else
7200 l2cap_do_start(chan);
7201 }
7202
7203 err = 0;
7204
7205chan_unlock:
7206 l2cap_chan_unlock(chan);
7207 mutex_unlock(&conn->chan_lock);
7208done:
7209 hci_dev_unlock(hdev);
7210 hci_dev_put(hdev);
7211 return err;
7212}
7213EXPORT_SYMBOL_GPL(l2cap_chan_connect);
7214
7215/* ---- L2CAP interface with lower layer (HCI) ---- */
7216
7217int l2cap_connect_ind(struct hci_dev *hdev, bdaddr_t *bdaddr)
7218{
7219 int exact = 0, lm1 = 0, lm2 = 0;
7220 struct l2cap_chan *c;
7221
7222 BT_DBG("hdev %s, bdaddr %pMR", hdev->name, bdaddr);
7223
7224 /* Find listening sockets and check their link_mode */
7225 read_lock(&chan_list_lock);
7226 list_for_each_entry(c, &chan_list, global_l) {
7227 if (c->state != BT_LISTEN)
7228 continue;
7229
7230 if (!bacmp(&c->src, &hdev->bdaddr)) {
7231 lm1 |= HCI_LM_ACCEPT;
7232 if (test_bit(FLAG_ROLE_SWITCH, &c->flags))
7233 lm1 |= HCI_LM_MASTER;
7234 exact++;
7235 } else if (!bacmp(&c->src, BDADDR_ANY)) {
7236 lm2 |= HCI_LM_ACCEPT;
7237 if (test_bit(FLAG_ROLE_SWITCH, &c->flags))
7238 lm2 |= HCI_LM_MASTER;
7239 }
7240 }
7241 read_unlock(&chan_list_lock);
7242
7243 return exact ? lm1 : lm2;
7244}
7245
7246/* Find the next fixed channel in BT_LISTEN state, continue iteration
7247 * from an existing channel in the list or from the beginning of the
7248 * global list (by passing NULL as first parameter).
7249 */
7250static struct l2cap_chan *l2cap_global_fixed_chan(struct l2cap_chan *c,
7251 struct hci_conn *hcon)
7252{
7253 u8 src_type = bdaddr_src_type(hcon);
7254
7255 read_lock(&chan_list_lock);
7256
7257 if (c)
7258 c = list_next_entry(c, global_l);
7259 else
7260 c = list_entry(chan_list.next, typeof(*c), global_l);
7261
7262 list_for_each_entry_from(c, &chan_list, global_l) {
7263 if (c->chan_type != L2CAP_CHAN_FIXED)
7264 continue;
7265 if (c->state != BT_LISTEN)
7266 continue;
7267 if (bacmp(&c->src, &hcon->src) && bacmp(&c->src, BDADDR_ANY))
7268 continue;
7269 if (src_type != c->src_type)
7270 continue;
7271
7272 l2cap_chan_hold(c);
7273 read_unlock(&chan_list_lock);
7274 return c;
7275 }
7276
7277 read_unlock(&chan_list_lock);
7278
7279 return NULL;
7280}
7281
7282static void l2cap_connect_cfm(struct hci_conn *hcon, u8 status)
7283{
7284 struct hci_dev *hdev = hcon->hdev;
7285 struct l2cap_conn *conn;
7286 struct l2cap_chan *pchan;
7287 u8 dst_type;
7288
7289 if (hcon->type != ACL_LINK && hcon->type != LE_LINK)
7290 return;
7291
7292 BT_DBG("hcon %p bdaddr %pMR status %d", hcon, &hcon->dst, status);
7293
7294 if (status) {
7295 l2cap_conn_del(hcon, bt_to_errno(status));
7296 return;
7297 }
7298
7299 conn = l2cap_conn_add(hcon);
7300 if (!conn)
7301 return;
7302
7303 dst_type = bdaddr_dst_type(hcon);
7304
7305 /* If device is blocked, do not create channels for it */
7306 if (hci_bdaddr_list_lookup(&hdev->blacklist, &hcon->dst, dst_type))
7307 return;
7308
7309 /* Find fixed channels and notify them of the new connection. We
7310 * use multiple individual lookups, continuing each time where
7311 * we left off, because the list lock would prevent calling the
7312 * potentially sleeping l2cap_chan_lock() function.
7313 */
7314 pchan = l2cap_global_fixed_chan(NULL, hcon);
7315 while (pchan) {
7316 struct l2cap_chan *chan, *next;
7317
7318 /* Client fixed channels should override server ones */
7319 if (__l2cap_get_chan_by_dcid(conn, pchan->scid))
7320 goto next;
7321
7322 l2cap_chan_lock(pchan);
7323 chan = pchan->ops->new_connection(pchan);
7324 if (chan) {
7325 bacpy(&chan->src, &hcon->src);
7326 bacpy(&chan->dst, &hcon->dst);
7327 chan->src_type = bdaddr_src_type(hcon);
7328 chan->dst_type = dst_type;
7329
7330 __l2cap_chan_add(conn, chan);
7331 }
7332
7333 l2cap_chan_unlock(pchan);
7334next:
7335 next = l2cap_global_fixed_chan(pchan, hcon);
7336 l2cap_chan_put(pchan);
7337 pchan = next;
7338 }
7339
7340 l2cap_conn_ready(conn);
7341}
7342
7343int l2cap_disconn_ind(struct hci_conn *hcon)
7344{
7345 struct l2cap_conn *conn = hcon->l2cap_data;
7346
7347 BT_DBG("hcon %p", hcon);
7348
7349 if (!conn)
7350 return HCI_ERROR_REMOTE_USER_TERM;
7351 return conn->disc_reason;
7352}
7353
7354static void l2cap_disconn_cfm(struct hci_conn *hcon, u8 reason)
7355{
7356 if (hcon->type != ACL_LINK && hcon->type != LE_LINK)
7357 return;
7358
7359 BT_DBG("hcon %p reason %d", hcon, reason);
7360
7361 l2cap_conn_del(hcon, bt_to_errno(reason));
7362}
7363
7364static inline void l2cap_check_encryption(struct l2cap_chan *chan, u8 encrypt)
7365{
7366 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED)
7367 return;
7368
7369 if (encrypt == 0x00) {
7370 if (chan->sec_level == BT_SECURITY_MEDIUM) {
7371 __set_chan_timer(chan, L2CAP_ENC_TIMEOUT);
7372 } else if (chan->sec_level == BT_SECURITY_HIGH ||
7373 chan->sec_level == BT_SECURITY_FIPS)
7374 l2cap_chan_close(chan, ECONNREFUSED);
7375 } else {
7376 if (chan->sec_level == BT_SECURITY_MEDIUM)
7377 __clear_chan_timer(chan);
7378 }
7379}
7380
7381static void l2cap_security_cfm(struct hci_conn *hcon, u8 status, u8 encrypt)
7382{
7383 struct l2cap_conn *conn = hcon->l2cap_data;
7384 struct l2cap_chan *chan;
7385
7386 if (!conn)
7387 return;
7388
7389 BT_DBG("conn %p status 0x%2.2x encrypt %u", conn, status, encrypt);
7390
7391 mutex_lock(&conn->chan_lock);
7392
7393 list_for_each_entry(chan, &conn->chan_l, list) {
7394 l2cap_chan_lock(chan);
7395
7396 BT_DBG("chan %p scid 0x%4.4x state %s", chan, chan->scid,
7397 state_to_string(chan->state));
7398
7399 if (chan->scid == L2CAP_CID_A2MP) {
7400 l2cap_chan_unlock(chan);
7401 continue;
7402 }
7403
7404 if (!status && encrypt)
7405 chan->sec_level = hcon->sec_level;
7406
7407 if (!__l2cap_no_conn_pending(chan)) {
7408 l2cap_chan_unlock(chan);
7409 continue;
7410 }
7411
7412 if (!status && (chan->state == BT_CONNECTED ||
7413 chan->state == BT_CONFIG)) {
7414 chan->ops->resume(chan);
7415 l2cap_check_encryption(chan, encrypt);
7416 l2cap_chan_unlock(chan);
7417 continue;
7418 }
7419
7420 if (chan->state == BT_CONNECT) {
7421 if (!status)
7422 l2cap_start_connection(chan);
7423 else
7424 __set_chan_timer(chan, L2CAP_DISC_TIMEOUT);
7425 } else if (chan->state == BT_CONNECT2 &&
7426 chan->mode != L2CAP_MODE_LE_FLOWCTL) {
7427 struct l2cap_conn_rsp rsp;
7428 __u16 res, stat;
7429
7430 if (!status) {
7431 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) {
7432 res = L2CAP_CR_PEND;
7433 stat = L2CAP_CS_AUTHOR_PEND;
7434 chan->ops->defer(chan);
7435 } else {
7436 l2cap_state_change(chan, BT_CONFIG);
7437 res = L2CAP_CR_SUCCESS;
7438 stat = L2CAP_CS_NO_INFO;
7439 }
7440 } else {
7441 l2cap_state_change(chan, BT_DISCONN);
7442 __set_chan_timer(chan, L2CAP_DISC_TIMEOUT);
7443 res = L2CAP_CR_SEC_BLOCK;
7444 stat = L2CAP_CS_NO_INFO;
7445 }
7446
7447 rsp.scid = cpu_to_le16(chan->dcid);
7448 rsp.dcid = cpu_to_le16(chan->scid);
7449 rsp.result = cpu_to_le16(res);
7450 rsp.status = cpu_to_le16(stat);
7451 l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_RSP,
7452 sizeof(rsp), &rsp);
7453
7454 if (!test_bit(CONF_REQ_SENT, &chan->conf_state) &&
7455 res == L2CAP_CR_SUCCESS) {
7456 char buf[128];
7457 set_bit(CONF_REQ_SENT, &chan->conf_state);
7458 l2cap_send_cmd(conn, l2cap_get_ident(conn),
7459 L2CAP_CONF_REQ,
7460 l2cap_build_conf_req(chan, buf),
7461 buf);
7462 chan->num_conf_req++;
7463 }
7464 }
7465
7466 l2cap_chan_unlock(chan);
7467 }
7468
7469 mutex_unlock(&conn->chan_lock);
7470}
7471
7472void l2cap_recv_acldata(struct hci_conn *hcon, struct sk_buff *skb, u16 flags)
7473{
7474 struct l2cap_conn *conn = hcon->l2cap_data;
7475 struct l2cap_hdr *hdr;
7476 int len;
7477
7478 /* For AMP controller do not create l2cap conn */
7479 if (!conn && hcon->hdev->dev_type != HCI_PRIMARY)
7480 goto drop;
7481
7482 if (!conn)
7483 conn = l2cap_conn_add(hcon);
7484
7485 if (!conn)
7486 goto drop;
7487
7488 BT_DBG("conn %p len %d flags 0x%x", conn, skb->len, flags);
7489
7490 switch (flags) {
7491 case ACL_START:
7492 case ACL_START_NO_FLUSH:
7493 case ACL_COMPLETE:
7494 if (conn->rx_len) {
7495 BT_ERR("Unexpected start frame (len %d)", skb->len);
7496 kfree_skb(conn->rx_skb);
7497 conn->rx_skb = NULL;
7498 conn->rx_len = 0;
7499 l2cap_conn_unreliable(conn, ECOMM);
7500 }
7501
7502 /* Start fragment always begin with Basic L2CAP header */
7503 if (skb->len < L2CAP_HDR_SIZE) {
7504 BT_ERR("Frame is too short (len %d)", skb->len);
7505 l2cap_conn_unreliable(conn, ECOMM);
7506 goto drop;
7507 }
7508
7509 hdr = (struct l2cap_hdr *) skb->data;
7510 len = __le16_to_cpu(hdr->len) + L2CAP_HDR_SIZE;
7511
7512 if (len == skb->len) {
7513 /* Complete frame received */
7514 l2cap_recv_frame(conn, skb);
7515 return;
7516 }
7517
7518 BT_DBG("Start: total len %d, frag len %d", len, skb->len);
7519
7520 if (skb->len > len) {
7521 BT_ERR("Frame is too long (len %d, expected len %d)",
7522 skb->len, len);
7523 l2cap_conn_unreliable(conn, ECOMM);
7524 goto drop;
7525 }
7526
7527 /* Allocate skb for the complete frame (with header) */
7528 conn->rx_skb = bt_skb_alloc(len, GFP_KERNEL);
7529 if (!conn->rx_skb)
7530 goto drop;
7531
7532 skb_copy_from_linear_data(skb, skb_put(conn->rx_skb, skb->len),
7533 skb->len);
7534 conn->rx_len = len - skb->len;
7535 break;
7536
7537 case ACL_CONT:
7538 BT_DBG("Cont: frag len %d (expecting %d)", skb->len, conn->rx_len);
7539
7540 if (!conn->rx_len) {
7541 BT_ERR("Unexpected continuation frame (len %d)", skb->len);
7542 l2cap_conn_unreliable(conn, ECOMM);
7543 goto drop;
7544 }
7545
7546 if (skb->len > conn->rx_len) {
7547 BT_ERR("Fragment is too long (len %d, expected %d)",
7548 skb->len, conn->rx_len);
7549 kfree_skb(conn->rx_skb);
7550 conn->rx_skb = NULL;
7551 conn->rx_len = 0;
7552 l2cap_conn_unreliable(conn, ECOMM);
7553 goto drop;
7554 }
7555
7556 skb_copy_from_linear_data(skb, skb_put(conn->rx_skb, skb->len),
7557 skb->len);
7558 conn->rx_len -= skb->len;
7559
7560 if (!conn->rx_len) {
7561 /* Complete frame received. l2cap_recv_frame
7562 * takes ownership of the skb so set the global
7563 * rx_skb pointer to NULL first.
7564 */
7565 struct sk_buff *rx_skb = conn->rx_skb;
7566 conn->rx_skb = NULL;
7567 l2cap_recv_frame(conn, rx_skb);
7568 }
7569 break;
7570 }
7571
7572drop:
7573 kfree_skb(skb);
7574}
7575
7576static struct hci_cb l2cap_cb = {
7577 .name = "L2CAP",
7578 .connect_cfm = l2cap_connect_cfm,
7579 .disconn_cfm = l2cap_disconn_cfm,
7580 .security_cfm = l2cap_security_cfm,
7581};
7582
7583static int l2cap_debugfs_show(struct seq_file *f, void *p)
7584{
7585 struct l2cap_chan *c;
7586
7587 read_lock(&chan_list_lock);
7588
7589 list_for_each_entry(c, &chan_list, global_l) {
7590 seq_printf(f, "%pMR (%u) %pMR (%u) %d %d 0x%4.4x 0x%4.4x %d %d %d %d\n",
7591 &c->src, c->src_type, &c->dst, c->dst_type,
7592 c->state, __le16_to_cpu(c->psm),
7593 c->scid, c->dcid, c->imtu, c->omtu,
7594 c->sec_level, c->mode);
7595 }
7596
7597 read_unlock(&chan_list_lock);
7598
7599 return 0;
7600}
7601
7602static int l2cap_debugfs_open(struct inode *inode, struct file *file)
7603{
7604 return single_open(file, l2cap_debugfs_show, inode->i_private);
7605}
7606
7607static const struct file_operations l2cap_debugfs_fops = {
7608 .open = l2cap_debugfs_open,
7609 .read = seq_read,
7610 .llseek = seq_lseek,
7611 .release = single_release,
7612};
7613
7614static struct dentry *l2cap_debugfs;
7615
7616int __init l2cap_init(void)
7617{
7618 int err;
7619
7620 err = l2cap_init_sockets();
7621 if (err < 0)
7622 return err;
7623
7624 hci_register_cb(&l2cap_cb);
7625
7626 if (IS_ERR_OR_NULL(bt_debugfs))
7627 return 0;
7628
7629 l2cap_debugfs = debugfs_create_file("l2cap", 0444, bt_debugfs,
7630 NULL, &l2cap_debugfs_fops);
7631
7632 debugfs_create_u16("l2cap_le_max_credits", 0644, bt_debugfs,
7633 &le_max_credits);
7634 debugfs_create_u16("l2cap_le_default_mps", 0644, bt_debugfs,
7635 &le_default_mps);
7636
7637 return 0;
7638}
7639
7640void l2cap_exit(void)
7641{
7642 debugfs_remove(l2cap_debugfs);
7643 hci_unregister_cb(&l2cap_cb);
7644 l2cap_cleanup_sockets();
7645}
7646
7647module_param(disable_ertm, bool, 0644);
7648MODULE_PARM_DESC(disable_ertm, "Disable enhanced retransmission mode");