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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
36#include <net/bluetooth/bluetooth.h>
37#include <net/bluetooth/hci_core.h>
38#include <net/bluetooth/l2cap.h>
39
40#include "smp.h"
41#include "a2mp.h"
42#include "amp.h"
43
44#define LE_FLOWCTL_MAX_CREDITS 65535
45
46bool disable_ertm;
47
48static u32 l2cap_feat_mask = L2CAP_FEAT_FIXED_CHAN | L2CAP_FEAT_UCD;
49
50static LIST_HEAD(chan_list);
51static DEFINE_RWLOCK(chan_list_lock);
52
53static u16 le_max_credits = L2CAP_LE_MAX_CREDITS;
54static u16 le_default_mps = L2CAP_LE_DEFAULT_MPS;
55
56static struct sk_buff *l2cap_build_cmd(struct l2cap_conn *conn,
57 u8 code, u8 ident, u16 dlen, void *data);
58static void l2cap_send_cmd(struct l2cap_conn *conn, u8 ident, u8 code, u16 len,
59 void *data);
60static int l2cap_build_conf_req(struct l2cap_chan *chan, void *data);
61static void l2cap_send_disconn_req(struct l2cap_chan *chan, int err);
62
63static void l2cap_tx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
64 struct sk_buff_head *skbs, u8 event);
65
66static inline u8 bdaddr_type(u8 link_type, u8 bdaddr_type)
67{
68 if (link_type == LE_LINK) {
69 if (bdaddr_type == ADDR_LE_DEV_PUBLIC)
70 return BDADDR_LE_PUBLIC;
71 else
72 return BDADDR_LE_RANDOM;
73 }
74
75 return BDADDR_BREDR;
76}
77
78static inline u8 bdaddr_src_type(struct hci_conn *hcon)
79{
80 return bdaddr_type(hcon->type, hcon->src_type);
81}
82
83static inline u8 bdaddr_dst_type(struct hci_conn *hcon)
84{
85 return bdaddr_type(hcon->type, hcon->dst_type);
86}
87
88/* ---- L2CAP channels ---- */
89
90static struct l2cap_chan *__l2cap_get_chan_by_dcid(struct l2cap_conn *conn,
91 u16 cid)
92{
93 struct l2cap_chan *c;
94
95 list_for_each_entry(c, &conn->chan_l, list) {
96 if (c->dcid == cid)
97 return c;
98 }
99 return NULL;
100}
101
102static struct l2cap_chan *__l2cap_get_chan_by_scid(struct l2cap_conn *conn,
103 u16 cid)
104{
105 struct l2cap_chan *c;
106
107 list_for_each_entry(c, &conn->chan_l, list) {
108 if (c->scid == cid)
109 return c;
110 }
111 return NULL;
112}
113
114/* Find channel with given SCID.
115 * Returns locked channel. */
116static struct l2cap_chan *l2cap_get_chan_by_scid(struct l2cap_conn *conn,
117 u16 cid)
118{
119 struct l2cap_chan *c;
120
121 mutex_lock(&conn->chan_lock);
122 c = __l2cap_get_chan_by_scid(conn, cid);
123 if (c)
124 l2cap_chan_lock(c);
125 mutex_unlock(&conn->chan_lock);
126
127 return c;
128}
129
130/* Find channel with given DCID.
131 * Returns locked channel.
132 */
133static struct l2cap_chan *l2cap_get_chan_by_dcid(struct l2cap_conn *conn,
134 u16 cid)
135{
136 struct l2cap_chan *c;
137
138 mutex_lock(&conn->chan_lock);
139 c = __l2cap_get_chan_by_dcid(conn, cid);
140 if (c)
141 l2cap_chan_lock(c);
142 mutex_unlock(&conn->chan_lock);
143
144 return c;
145}
146
147static struct l2cap_chan *__l2cap_get_chan_by_ident(struct l2cap_conn *conn,
148 u8 ident)
149{
150 struct l2cap_chan *c;
151
152 list_for_each_entry(c, &conn->chan_l, list) {
153 if (c->ident == ident)
154 return c;
155 }
156 return NULL;
157}
158
159static struct l2cap_chan *l2cap_get_chan_by_ident(struct l2cap_conn *conn,
160 u8 ident)
161{
162 struct l2cap_chan *c;
163
164 mutex_lock(&conn->chan_lock);
165 c = __l2cap_get_chan_by_ident(conn, ident);
166 if (c)
167 l2cap_chan_lock(c);
168 mutex_unlock(&conn->chan_lock);
169
170 return c;
171}
172
173static struct l2cap_chan *__l2cap_global_chan_by_addr(__le16 psm, bdaddr_t *src)
174{
175 struct l2cap_chan *c;
176
177 list_for_each_entry(c, &chan_list, global_l) {
178 if (c->sport == psm && !bacmp(&c->src, src))
179 return c;
180 }
181 return NULL;
182}
183
184int l2cap_add_psm(struct l2cap_chan *chan, bdaddr_t *src, __le16 psm)
185{
186 int err;
187
188 write_lock(&chan_list_lock);
189
190 if (psm && __l2cap_global_chan_by_addr(psm, src)) {
191 err = -EADDRINUSE;
192 goto done;
193 }
194
195 if (psm) {
196 chan->psm = psm;
197 chan->sport = psm;
198 err = 0;
199 } else {
200 u16 p, start, end, incr;
201
202 if (chan->src_type == BDADDR_BREDR) {
203 start = L2CAP_PSM_DYN_START;
204 end = L2CAP_PSM_AUTO_END;
205 incr = 2;
206 } else {
207 start = L2CAP_PSM_LE_DYN_START;
208 end = L2CAP_PSM_LE_DYN_END;
209 incr = 1;
210 }
211
212 err = -EINVAL;
213 for (p = start; p <= end; p += incr)
214 if (!__l2cap_global_chan_by_addr(cpu_to_le16(p), src)) {
215 chan->psm = cpu_to_le16(p);
216 chan->sport = cpu_to_le16(p);
217 err = 0;
218 break;
219 }
220 }
221
222done:
223 write_unlock(&chan_list_lock);
224 return err;
225}
226EXPORT_SYMBOL_GPL(l2cap_add_psm);
227
228int l2cap_add_scid(struct l2cap_chan *chan, __u16 scid)
229{
230 write_lock(&chan_list_lock);
231
232 /* Override the defaults (which are for conn-oriented) */
233 chan->omtu = L2CAP_DEFAULT_MTU;
234 chan->chan_type = L2CAP_CHAN_FIXED;
235
236 chan->scid = scid;
237
238 write_unlock(&chan_list_lock);
239
240 return 0;
241}
242
243static u16 l2cap_alloc_cid(struct l2cap_conn *conn)
244{
245 u16 cid, dyn_end;
246
247 if (conn->hcon->type == LE_LINK)
248 dyn_end = L2CAP_CID_LE_DYN_END;
249 else
250 dyn_end = L2CAP_CID_DYN_END;
251
252 for (cid = L2CAP_CID_DYN_START; cid <= dyn_end; cid++) {
253 if (!__l2cap_get_chan_by_scid(conn, cid))
254 return cid;
255 }
256
257 return 0;
258}
259
260static void l2cap_state_change(struct l2cap_chan *chan, int state)
261{
262 BT_DBG("chan %p %s -> %s", chan, state_to_string(chan->state),
263 state_to_string(state));
264
265 chan->state = state;
266 chan->ops->state_change(chan, state, 0);
267}
268
269static inline void l2cap_state_change_and_error(struct l2cap_chan *chan,
270 int state, int err)
271{
272 chan->state = state;
273 chan->ops->state_change(chan, chan->state, err);
274}
275
276static inline void l2cap_chan_set_err(struct l2cap_chan *chan, int err)
277{
278 chan->ops->state_change(chan, chan->state, err);
279}
280
281static void __set_retrans_timer(struct l2cap_chan *chan)
282{
283 if (!delayed_work_pending(&chan->monitor_timer) &&
284 chan->retrans_timeout) {
285 l2cap_set_timer(chan, &chan->retrans_timer,
286 msecs_to_jiffies(chan->retrans_timeout));
287 }
288}
289
290static void __set_monitor_timer(struct l2cap_chan *chan)
291{
292 __clear_retrans_timer(chan);
293 if (chan->monitor_timeout) {
294 l2cap_set_timer(chan, &chan->monitor_timer,
295 msecs_to_jiffies(chan->monitor_timeout));
296 }
297}
298
299static struct sk_buff *l2cap_ertm_seq_in_queue(struct sk_buff_head *head,
300 u16 seq)
301{
302 struct sk_buff *skb;
303
304 skb_queue_walk(head, skb) {
305 if (bt_cb(skb)->l2cap.txseq == seq)
306 return skb;
307 }
308
309 return NULL;
310}
311
312/* ---- L2CAP sequence number lists ---- */
313
314/* For ERTM, ordered lists of sequence numbers must be tracked for
315 * SREJ requests that are received and for frames that are to be
316 * retransmitted. These seq_list functions implement a singly-linked
317 * list in an array, where membership in the list can also be checked
318 * in constant time. Items can also be added to the tail of the list
319 * and removed from the head in constant time, without further memory
320 * allocs or frees.
321 */
322
323static int l2cap_seq_list_init(struct l2cap_seq_list *seq_list, u16 size)
324{
325 size_t alloc_size, i;
326
327 /* Allocated size is a power of 2 to map sequence numbers
328 * (which may be up to 14 bits) in to a smaller array that is
329 * sized for the negotiated ERTM transmit windows.
330 */
331 alloc_size = roundup_pow_of_two(size);
332
333 seq_list->list = kmalloc(sizeof(u16) * alloc_size, GFP_KERNEL);
334 if (!seq_list->list)
335 return -ENOMEM;
336
337 seq_list->mask = alloc_size - 1;
338 seq_list->head = L2CAP_SEQ_LIST_CLEAR;
339 seq_list->tail = L2CAP_SEQ_LIST_CLEAR;
340 for (i = 0; i < alloc_size; i++)
341 seq_list->list[i] = L2CAP_SEQ_LIST_CLEAR;
342
343 return 0;
344}
345
346static inline void l2cap_seq_list_free(struct l2cap_seq_list *seq_list)
347{
348 kfree(seq_list->list);
349}
350
351static inline bool l2cap_seq_list_contains(struct l2cap_seq_list *seq_list,
352 u16 seq)
353{
354 /* Constant-time check for list membership */
355 return seq_list->list[seq & seq_list->mask] != L2CAP_SEQ_LIST_CLEAR;
356}
357
358static inline u16 l2cap_seq_list_pop(struct l2cap_seq_list *seq_list)
359{
360 u16 seq = seq_list->head;
361 u16 mask = seq_list->mask;
362
363 seq_list->head = seq_list->list[seq & mask];
364 seq_list->list[seq & mask] = L2CAP_SEQ_LIST_CLEAR;
365
366 if (seq_list->head == L2CAP_SEQ_LIST_TAIL) {
367 seq_list->head = L2CAP_SEQ_LIST_CLEAR;
368 seq_list->tail = L2CAP_SEQ_LIST_CLEAR;
369 }
370
371 return seq;
372}
373
374static void l2cap_seq_list_clear(struct l2cap_seq_list *seq_list)
375{
376 u16 i;
377
378 if (seq_list->head == L2CAP_SEQ_LIST_CLEAR)
379 return;
380
381 for (i = 0; i <= seq_list->mask; i++)
382 seq_list->list[i] = L2CAP_SEQ_LIST_CLEAR;
383
384 seq_list->head = L2CAP_SEQ_LIST_CLEAR;
385 seq_list->tail = L2CAP_SEQ_LIST_CLEAR;
386}
387
388static void l2cap_seq_list_append(struct l2cap_seq_list *seq_list, u16 seq)
389{
390 u16 mask = seq_list->mask;
391
392 /* All appends happen in constant time */
393
394 if (seq_list->list[seq & mask] != L2CAP_SEQ_LIST_CLEAR)
395 return;
396
397 if (seq_list->tail == L2CAP_SEQ_LIST_CLEAR)
398 seq_list->head = seq;
399 else
400 seq_list->list[seq_list->tail & mask] = seq;
401
402 seq_list->tail = seq;
403 seq_list->list[seq & mask] = L2CAP_SEQ_LIST_TAIL;
404}
405
406static void l2cap_chan_timeout(struct work_struct *work)
407{
408 struct l2cap_chan *chan = container_of(work, struct l2cap_chan,
409 chan_timer.work);
410 struct l2cap_conn *conn = chan->conn;
411 int reason;
412
413 BT_DBG("chan %p state %s", chan, state_to_string(chan->state));
414
415 mutex_lock(&conn->chan_lock);
416 l2cap_chan_lock(chan);
417
418 if (chan->state == BT_CONNECTED || chan->state == BT_CONFIG)
419 reason = ECONNREFUSED;
420 else if (chan->state == BT_CONNECT &&
421 chan->sec_level != BT_SECURITY_SDP)
422 reason = ECONNREFUSED;
423 else
424 reason = ETIMEDOUT;
425
426 l2cap_chan_close(chan, reason);
427
428 l2cap_chan_unlock(chan);
429
430 chan->ops->close(chan);
431 mutex_unlock(&conn->chan_lock);
432
433 l2cap_chan_put(chan);
434}
435
436struct l2cap_chan *l2cap_chan_create(void)
437{
438 struct l2cap_chan *chan;
439
440 chan = kzalloc(sizeof(*chan), GFP_ATOMIC);
441 if (!chan)
442 return NULL;
443
444 mutex_init(&chan->lock);
445
446 /* Set default lock nesting level */
447 atomic_set(&chan->nesting, L2CAP_NESTING_NORMAL);
448
449 write_lock(&chan_list_lock);
450 list_add(&chan->global_l, &chan_list);
451 write_unlock(&chan_list_lock);
452
453 INIT_DELAYED_WORK(&chan->chan_timer, l2cap_chan_timeout);
454
455 chan->state = BT_OPEN;
456
457 kref_init(&chan->kref);
458
459 /* This flag is cleared in l2cap_chan_ready() */
460 set_bit(CONF_NOT_COMPLETE, &chan->conf_state);
461
462 BT_DBG("chan %p", chan);
463
464 return chan;
465}
466EXPORT_SYMBOL_GPL(l2cap_chan_create);
467
468static void l2cap_chan_destroy(struct kref *kref)
469{
470 struct l2cap_chan *chan = container_of(kref, struct l2cap_chan, kref);
471
472 BT_DBG("chan %p", chan);
473
474 write_lock(&chan_list_lock);
475 list_del(&chan->global_l);
476 write_unlock(&chan_list_lock);
477
478 kfree(chan);
479}
480
481void l2cap_chan_hold(struct l2cap_chan *c)
482{
483 BT_DBG("chan %p orig refcnt %d", c, atomic_read(&c->kref.refcount));
484
485 kref_get(&c->kref);
486}
487
488void l2cap_chan_put(struct l2cap_chan *c)
489{
490 BT_DBG("chan %p orig refcnt %d", c, atomic_read(&c->kref.refcount));
491
492 kref_put(&c->kref, l2cap_chan_destroy);
493}
494EXPORT_SYMBOL_GPL(l2cap_chan_put);
495
496void l2cap_chan_set_defaults(struct l2cap_chan *chan)
497{
498 chan->fcs = L2CAP_FCS_CRC16;
499 chan->max_tx = L2CAP_DEFAULT_MAX_TX;
500 chan->tx_win = L2CAP_DEFAULT_TX_WINDOW;
501 chan->tx_win_max = L2CAP_DEFAULT_TX_WINDOW;
502 chan->remote_max_tx = chan->max_tx;
503 chan->remote_tx_win = chan->tx_win;
504 chan->ack_win = L2CAP_DEFAULT_TX_WINDOW;
505 chan->sec_level = BT_SECURITY_LOW;
506 chan->flush_to = L2CAP_DEFAULT_FLUSH_TO;
507 chan->retrans_timeout = L2CAP_DEFAULT_RETRANS_TO;
508 chan->monitor_timeout = L2CAP_DEFAULT_MONITOR_TO;
509 chan->conf_state = 0;
510
511 set_bit(FLAG_FORCE_ACTIVE, &chan->flags);
512}
513EXPORT_SYMBOL_GPL(l2cap_chan_set_defaults);
514
515static void l2cap_le_flowctl_init(struct l2cap_chan *chan)
516{
517 chan->sdu = NULL;
518 chan->sdu_last_frag = NULL;
519 chan->sdu_len = 0;
520 chan->tx_credits = 0;
521 chan->rx_credits = le_max_credits;
522 chan->mps = min_t(u16, chan->imtu, le_default_mps);
523
524 skb_queue_head_init(&chan->tx_q);
525}
526
527void __l2cap_chan_add(struct l2cap_conn *conn, struct l2cap_chan *chan)
528{
529 BT_DBG("conn %p, psm 0x%2.2x, dcid 0x%4.4x", conn,
530 __le16_to_cpu(chan->psm), chan->dcid);
531
532 conn->disc_reason = HCI_ERROR_REMOTE_USER_TERM;
533
534 chan->conn = conn;
535
536 switch (chan->chan_type) {
537 case L2CAP_CHAN_CONN_ORIENTED:
538 /* Alloc CID for connection-oriented socket */
539 chan->scid = l2cap_alloc_cid(conn);
540 if (conn->hcon->type == ACL_LINK)
541 chan->omtu = L2CAP_DEFAULT_MTU;
542 break;
543
544 case L2CAP_CHAN_CONN_LESS:
545 /* Connectionless socket */
546 chan->scid = L2CAP_CID_CONN_LESS;
547 chan->dcid = L2CAP_CID_CONN_LESS;
548 chan->omtu = L2CAP_DEFAULT_MTU;
549 break;
550
551 case L2CAP_CHAN_FIXED:
552 /* Caller will set CID and CID specific MTU values */
553 break;
554
555 default:
556 /* Raw socket can send/recv signalling messages only */
557 chan->scid = L2CAP_CID_SIGNALING;
558 chan->dcid = L2CAP_CID_SIGNALING;
559 chan->omtu = L2CAP_DEFAULT_MTU;
560 }
561
562 chan->local_id = L2CAP_BESTEFFORT_ID;
563 chan->local_stype = L2CAP_SERV_BESTEFFORT;
564 chan->local_msdu = L2CAP_DEFAULT_MAX_SDU_SIZE;
565 chan->local_sdu_itime = L2CAP_DEFAULT_SDU_ITIME;
566 chan->local_acc_lat = L2CAP_DEFAULT_ACC_LAT;
567 chan->local_flush_to = L2CAP_EFS_DEFAULT_FLUSH_TO;
568
569 l2cap_chan_hold(chan);
570
571 /* Only keep a reference for fixed channels if they requested it */
572 if (chan->chan_type != L2CAP_CHAN_FIXED ||
573 test_bit(FLAG_HOLD_HCI_CONN, &chan->flags))
574 hci_conn_hold(conn->hcon);
575
576 list_add(&chan->list, &conn->chan_l);
577}
578
579void l2cap_chan_add(struct l2cap_conn *conn, struct l2cap_chan *chan)
580{
581 mutex_lock(&conn->chan_lock);
582 __l2cap_chan_add(conn, chan);
583 mutex_unlock(&conn->chan_lock);
584}
585
586void l2cap_chan_del(struct l2cap_chan *chan, int err)
587{
588 struct l2cap_conn *conn = chan->conn;
589
590 __clear_chan_timer(chan);
591
592 BT_DBG("chan %p, conn %p, err %d, state %s", chan, conn, err,
593 state_to_string(chan->state));
594
595 chan->ops->teardown(chan, err);
596
597 if (conn) {
598 struct amp_mgr *mgr = conn->hcon->amp_mgr;
599 /* Delete from channel list */
600 list_del(&chan->list);
601
602 l2cap_chan_put(chan);
603
604 chan->conn = NULL;
605
606 /* Reference was only held for non-fixed channels or
607 * fixed channels that explicitly requested it using the
608 * FLAG_HOLD_HCI_CONN flag.
609 */
610 if (chan->chan_type != L2CAP_CHAN_FIXED ||
611 test_bit(FLAG_HOLD_HCI_CONN, &chan->flags))
612 hci_conn_drop(conn->hcon);
613
614 if (mgr && mgr->bredr_chan == chan)
615 mgr->bredr_chan = NULL;
616 }
617
618 if (chan->hs_hchan) {
619 struct hci_chan *hs_hchan = chan->hs_hchan;
620
621 BT_DBG("chan %p disconnect hs_hchan %p", chan, hs_hchan);
622 amp_disconnect_logical_link(hs_hchan);
623 }
624
625 if (test_bit(CONF_NOT_COMPLETE, &chan->conf_state))
626 return;
627
628 switch(chan->mode) {
629 case L2CAP_MODE_BASIC:
630 break;
631
632 case L2CAP_MODE_LE_FLOWCTL:
633 skb_queue_purge(&chan->tx_q);
634 break;
635
636 case L2CAP_MODE_ERTM:
637 __clear_retrans_timer(chan);
638 __clear_monitor_timer(chan);
639 __clear_ack_timer(chan);
640
641 skb_queue_purge(&chan->srej_q);
642
643 l2cap_seq_list_free(&chan->srej_list);
644 l2cap_seq_list_free(&chan->retrans_list);
645
646 /* fall through */
647
648 case L2CAP_MODE_STREAMING:
649 skb_queue_purge(&chan->tx_q);
650 break;
651 }
652
653 return;
654}
655EXPORT_SYMBOL_GPL(l2cap_chan_del);
656
657static void l2cap_conn_update_id_addr(struct work_struct *work)
658{
659 struct l2cap_conn *conn = container_of(work, struct l2cap_conn,
660 id_addr_update_work);
661 struct hci_conn *hcon = conn->hcon;
662 struct l2cap_chan *chan;
663
664 mutex_lock(&conn->chan_lock);
665
666 list_for_each_entry(chan, &conn->chan_l, list) {
667 l2cap_chan_lock(chan);
668 bacpy(&chan->dst, &hcon->dst);
669 chan->dst_type = bdaddr_dst_type(hcon);
670 l2cap_chan_unlock(chan);
671 }
672
673 mutex_unlock(&conn->chan_lock);
674}
675
676static void l2cap_chan_le_connect_reject(struct l2cap_chan *chan)
677{
678 struct l2cap_conn *conn = chan->conn;
679 struct l2cap_le_conn_rsp rsp;
680 u16 result;
681
682 if (test_bit(FLAG_DEFER_SETUP, &chan->flags))
683 result = L2CAP_CR_AUTHORIZATION;
684 else
685 result = L2CAP_CR_BAD_PSM;
686
687 l2cap_state_change(chan, BT_DISCONN);
688
689 rsp.dcid = cpu_to_le16(chan->scid);
690 rsp.mtu = cpu_to_le16(chan->imtu);
691 rsp.mps = cpu_to_le16(chan->mps);
692 rsp.credits = cpu_to_le16(chan->rx_credits);
693 rsp.result = cpu_to_le16(result);
694
695 l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CONN_RSP, sizeof(rsp),
696 &rsp);
697}
698
699static void l2cap_chan_connect_reject(struct l2cap_chan *chan)
700{
701 struct l2cap_conn *conn = chan->conn;
702 struct l2cap_conn_rsp rsp;
703 u16 result;
704
705 if (test_bit(FLAG_DEFER_SETUP, &chan->flags))
706 result = L2CAP_CR_SEC_BLOCK;
707 else
708 result = L2CAP_CR_BAD_PSM;
709
710 l2cap_state_change(chan, BT_DISCONN);
711
712 rsp.scid = cpu_to_le16(chan->dcid);
713 rsp.dcid = cpu_to_le16(chan->scid);
714 rsp.result = cpu_to_le16(result);
715 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
716
717 l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_RSP, sizeof(rsp), &rsp);
718}
719
720void l2cap_chan_close(struct l2cap_chan *chan, int reason)
721{
722 struct l2cap_conn *conn = chan->conn;
723
724 BT_DBG("chan %p state %s", chan, state_to_string(chan->state));
725
726 switch (chan->state) {
727 case BT_LISTEN:
728 chan->ops->teardown(chan, 0);
729 break;
730
731 case BT_CONNECTED:
732 case BT_CONFIG:
733 if (chan->chan_type == L2CAP_CHAN_CONN_ORIENTED) {
734 __set_chan_timer(chan, chan->ops->get_sndtimeo(chan));
735 l2cap_send_disconn_req(chan, reason);
736 } else
737 l2cap_chan_del(chan, reason);
738 break;
739
740 case BT_CONNECT2:
741 if (chan->chan_type == L2CAP_CHAN_CONN_ORIENTED) {
742 if (conn->hcon->type == ACL_LINK)
743 l2cap_chan_connect_reject(chan);
744 else if (conn->hcon->type == LE_LINK)
745 l2cap_chan_le_connect_reject(chan);
746 }
747
748 l2cap_chan_del(chan, reason);
749 break;
750
751 case BT_CONNECT:
752 case BT_DISCONN:
753 l2cap_chan_del(chan, reason);
754 break;
755
756 default:
757 chan->ops->teardown(chan, 0);
758 break;
759 }
760}
761EXPORT_SYMBOL(l2cap_chan_close);
762
763static inline u8 l2cap_get_auth_type(struct l2cap_chan *chan)
764{
765 switch (chan->chan_type) {
766 case L2CAP_CHAN_RAW:
767 switch (chan->sec_level) {
768 case BT_SECURITY_HIGH:
769 case BT_SECURITY_FIPS:
770 return HCI_AT_DEDICATED_BONDING_MITM;
771 case BT_SECURITY_MEDIUM:
772 return HCI_AT_DEDICATED_BONDING;
773 default:
774 return HCI_AT_NO_BONDING;
775 }
776 break;
777 case L2CAP_CHAN_CONN_LESS:
778 if (chan->psm == cpu_to_le16(L2CAP_PSM_3DSP)) {
779 if (chan->sec_level == BT_SECURITY_LOW)
780 chan->sec_level = BT_SECURITY_SDP;
781 }
782 if (chan->sec_level == BT_SECURITY_HIGH ||
783 chan->sec_level == BT_SECURITY_FIPS)
784 return HCI_AT_NO_BONDING_MITM;
785 else
786 return HCI_AT_NO_BONDING;
787 break;
788 case L2CAP_CHAN_CONN_ORIENTED:
789 if (chan->psm == cpu_to_le16(L2CAP_PSM_SDP)) {
790 if (chan->sec_level == BT_SECURITY_LOW)
791 chan->sec_level = BT_SECURITY_SDP;
792
793 if (chan->sec_level == BT_SECURITY_HIGH ||
794 chan->sec_level == BT_SECURITY_FIPS)
795 return HCI_AT_NO_BONDING_MITM;
796 else
797 return HCI_AT_NO_BONDING;
798 }
799 /* fall through */
800 default:
801 switch (chan->sec_level) {
802 case BT_SECURITY_HIGH:
803 case BT_SECURITY_FIPS:
804 return HCI_AT_GENERAL_BONDING_MITM;
805 case BT_SECURITY_MEDIUM:
806 return HCI_AT_GENERAL_BONDING;
807 default:
808 return HCI_AT_NO_BONDING;
809 }
810 break;
811 }
812}
813
814/* Service level security */
815int l2cap_chan_check_security(struct l2cap_chan *chan, bool initiator)
816{
817 struct l2cap_conn *conn = chan->conn;
818 __u8 auth_type;
819
820 if (conn->hcon->type == LE_LINK)
821 return smp_conn_security(conn->hcon, chan->sec_level);
822
823 auth_type = l2cap_get_auth_type(chan);
824
825 return hci_conn_security(conn->hcon, chan->sec_level, auth_type,
826 initiator);
827}
828
829static u8 l2cap_get_ident(struct l2cap_conn *conn)
830{
831 u8 id;
832
833 /* Get next available identificator.
834 * 1 - 128 are used by kernel.
835 * 129 - 199 are reserved.
836 * 200 - 254 are used by utilities like l2ping, etc.
837 */
838
839 mutex_lock(&conn->ident_lock);
840
841 if (++conn->tx_ident > 128)
842 conn->tx_ident = 1;
843
844 id = conn->tx_ident;
845
846 mutex_unlock(&conn->ident_lock);
847
848 return id;
849}
850
851static void l2cap_send_cmd(struct l2cap_conn *conn, u8 ident, u8 code, u16 len,
852 void *data)
853{
854 struct sk_buff *skb = l2cap_build_cmd(conn, code, ident, len, data);
855 u8 flags;
856
857 BT_DBG("code 0x%2.2x", code);
858
859 if (!skb)
860 return;
861
862 /* Use NO_FLUSH if supported or we have an LE link (which does
863 * not support auto-flushing packets) */
864 if (lmp_no_flush_capable(conn->hcon->hdev) ||
865 conn->hcon->type == LE_LINK)
866 flags = ACL_START_NO_FLUSH;
867 else
868 flags = ACL_START;
869
870 bt_cb(skb)->force_active = BT_POWER_FORCE_ACTIVE_ON;
871 skb->priority = HCI_PRIO_MAX;
872
873 hci_send_acl(conn->hchan, skb, flags);
874}
875
876static bool __chan_is_moving(struct l2cap_chan *chan)
877{
878 return chan->move_state != L2CAP_MOVE_STABLE &&
879 chan->move_state != L2CAP_MOVE_WAIT_PREPARE;
880}
881
882static void l2cap_do_send(struct l2cap_chan *chan, struct sk_buff *skb)
883{
884 struct hci_conn *hcon = chan->conn->hcon;
885 u16 flags;
886
887 BT_DBG("chan %p, skb %p len %d priority %u", chan, skb, skb->len,
888 skb->priority);
889
890 if (chan->hs_hcon && !__chan_is_moving(chan)) {
891 if (chan->hs_hchan)
892 hci_send_acl(chan->hs_hchan, skb, ACL_COMPLETE);
893 else
894 kfree_skb(skb);
895
896 return;
897 }
898
899 /* Use NO_FLUSH for LE links (where this is the only option) or
900 * if the BR/EDR link supports it and flushing has not been
901 * explicitly requested (through FLAG_FLUSHABLE).
902 */
903 if (hcon->type == LE_LINK ||
904 (!test_bit(FLAG_FLUSHABLE, &chan->flags) &&
905 lmp_no_flush_capable(hcon->hdev)))
906 flags = ACL_START_NO_FLUSH;
907 else
908 flags = ACL_START;
909
910 bt_cb(skb)->force_active = test_bit(FLAG_FORCE_ACTIVE, &chan->flags);
911 hci_send_acl(chan->conn->hchan, skb, flags);
912}
913
914static void __unpack_enhanced_control(u16 enh, struct l2cap_ctrl *control)
915{
916 control->reqseq = (enh & L2CAP_CTRL_REQSEQ) >> L2CAP_CTRL_REQSEQ_SHIFT;
917 control->final = (enh & L2CAP_CTRL_FINAL) >> L2CAP_CTRL_FINAL_SHIFT;
918
919 if (enh & L2CAP_CTRL_FRAME_TYPE) {
920 /* S-Frame */
921 control->sframe = 1;
922 control->poll = (enh & L2CAP_CTRL_POLL) >> L2CAP_CTRL_POLL_SHIFT;
923 control->super = (enh & L2CAP_CTRL_SUPERVISE) >> L2CAP_CTRL_SUPER_SHIFT;
924
925 control->sar = 0;
926 control->txseq = 0;
927 } else {
928 /* I-Frame */
929 control->sframe = 0;
930 control->sar = (enh & L2CAP_CTRL_SAR) >> L2CAP_CTRL_SAR_SHIFT;
931 control->txseq = (enh & L2CAP_CTRL_TXSEQ) >> L2CAP_CTRL_TXSEQ_SHIFT;
932
933 control->poll = 0;
934 control->super = 0;
935 }
936}
937
938static void __unpack_extended_control(u32 ext, struct l2cap_ctrl *control)
939{
940 control->reqseq = (ext & L2CAP_EXT_CTRL_REQSEQ) >> L2CAP_EXT_CTRL_REQSEQ_SHIFT;
941 control->final = (ext & L2CAP_EXT_CTRL_FINAL) >> L2CAP_EXT_CTRL_FINAL_SHIFT;
942
943 if (ext & L2CAP_EXT_CTRL_FRAME_TYPE) {
944 /* S-Frame */
945 control->sframe = 1;
946 control->poll = (ext & L2CAP_EXT_CTRL_POLL) >> L2CAP_EXT_CTRL_POLL_SHIFT;
947 control->super = (ext & L2CAP_EXT_CTRL_SUPERVISE) >> L2CAP_EXT_CTRL_SUPER_SHIFT;
948
949 control->sar = 0;
950 control->txseq = 0;
951 } else {
952 /* I-Frame */
953 control->sframe = 0;
954 control->sar = (ext & L2CAP_EXT_CTRL_SAR) >> L2CAP_EXT_CTRL_SAR_SHIFT;
955 control->txseq = (ext & L2CAP_EXT_CTRL_TXSEQ) >> L2CAP_EXT_CTRL_TXSEQ_SHIFT;
956
957 control->poll = 0;
958 control->super = 0;
959 }
960}
961
962static inline void __unpack_control(struct l2cap_chan *chan,
963 struct sk_buff *skb)
964{
965 if (test_bit(FLAG_EXT_CTRL, &chan->flags)) {
966 __unpack_extended_control(get_unaligned_le32(skb->data),
967 &bt_cb(skb)->l2cap);
968 skb_pull(skb, L2CAP_EXT_CTRL_SIZE);
969 } else {
970 __unpack_enhanced_control(get_unaligned_le16(skb->data),
971 &bt_cb(skb)->l2cap);
972 skb_pull(skb, L2CAP_ENH_CTRL_SIZE);
973 }
974}
975
976static u32 __pack_extended_control(struct l2cap_ctrl *control)
977{
978 u32 packed;
979
980 packed = control->reqseq << L2CAP_EXT_CTRL_REQSEQ_SHIFT;
981 packed |= control->final << L2CAP_EXT_CTRL_FINAL_SHIFT;
982
983 if (control->sframe) {
984 packed |= control->poll << L2CAP_EXT_CTRL_POLL_SHIFT;
985 packed |= control->super << L2CAP_EXT_CTRL_SUPER_SHIFT;
986 packed |= L2CAP_EXT_CTRL_FRAME_TYPE;
987 } else {
988 packed |= control->sar << L2CAP_EXT_CTRL_SAR_SHIFT;
989 packed |= control->txseq << L2CAP_EXT_CTRL_TXSEQ_SHIFT;
990 }
991
992 return packed;
993}
994
995static u16 __pack_enhanced_control(struct l2cap_ctrl *control)
996{
997 u16 packed;
998
999 packed = control->reqseq << L2CAP_CTRL_REQSEQ_SHIFT;
1000 packed |= control->final << L2CAP_CTRL_FINAL_SHIFT;
1001
1002 if (control->sframe) {
1003 packed |= control->poll << L2CAP_CTRL_POLL_SHIFT;
1004 packed |= control->super << L2CAP_CTRL_SUPER_SHIFT;
1005 packed |= L2CAP_CTRL_FRAME_TYPE;
1006 } else {
1007 packed |= control->sar << L2CAP_CTRL_SAR_SHIFT;
1008 packed |= control->txseq << L2CAP_CTRL_TXSEQ_SHIFT;
1009 }
1010
1011 return packed;
1012}
1013
1014static inline void __pack_control(struct l2cap_chan *chan,
1015 struct l2cap_ctrl *control,
1016 struct sk_buff *skb)
1017{
1018 if (test_bit(FLAG_EXT_CTRL, &chan->flags)) {
1019 put_unaligned_le32(__pack_extended_control(control),
1020 skb->data + L2CAP_HDR_SIZE);
1021 } else {
1022 put_unaligned_le16(__pack_enhanced_control(control),
1023 skb->data + L2CAP_HDR_SIZE);
1024 }
1025}
1026
1027static inline unsigned int __ertm_hdr_size(struct l2cap_chan *chan)
1028{
1029 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
1030 return L2CAP_EXT_HDR_SIZE;
1031 else
1032 return L2CAP_ENH_HDR_SIZE;
1033}
1034
1035static struct sk_buff *l2cap_create_sframe_pdu(struct l2cap_chan *chan,
1036 u32 control)
1037{
1038 struct sk_buff *skb;
1039 struct l2cap_hdr *lh;
1040 int hlen = __ertm_hdr_size(chan);
1041
1042 if (chan->fcs == L2CAP_FCS_CRC16)
1043 hlen += L2CAP_FCS_SIZE;
1044
1045 skb = bt_skb_alloc(hlen, GFP_KERNEL);
1046
1047 if (!skb)
1048 return ERR_PTR(-ENOMEM);
1049
1050 lh = (struct l2cap_hdr *) skb_put(skb, L2CAP_HDR_SIZE);
1051 lh->len = cpu_to_le16(hlen - L2CAP_HDR_SIZE);
1052 lh->cid = cpu_to_le16(chan->dcid);
1053
1054 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
1055 put_unaligned_le32(control, skb_put(skb, L2CAP_EXT_CTRL_SIZE));
1056 else
1057 put_unaligned_le16(control, skb_put(skb, L2CAP_ENH_CTRL_SIZE));
1058
1059 if (chan->fcs == L2CAP_FCS_CRC16) {
1060 u16 fcs = crc16(0, (u8 *)skb->data, skb->len);
1061 put_unaligned_le16(fcs, skb_put(skb, L2CAP_FCS_SIZE));
1062 }
1063
1064 skb->priority = HCI_PRIO_MAX;
1065 return skb;
1066}
1067
1068static void l2cap_send_sframe(struct l2cap_chan *chan,
1069 struct l2cap_ctrl *control)
1070{
1071 struct sk_buff *skb;
1072 u32 control_field;
1073
1074 BT_DBG("chan %p, control %p", chan, control);
1075
1076 if (!control->sframe)
1077 return;
1078
1079 if (__chan_is_moving(chan))
1080 return;
1081
1082 if (test_and_clear_bit(CONN_SEND_FBIT, &chan->conn_state) &&
1083 !control->poll)
1084 control->final = 1;
1085
1086 if (control->super == L2CAP_SUPER_RR)
1087 clear_bit(CONN_RNR_SENT, &chan->conn_state);
1088 else if (control->super == L2CAP_SUPER_RNR)
1089 set_bit(CONN_RNR_SENT, &chan->conn_state);
1090
1091 if (control->super != L2CAP_SUPER_SREJ) {
1092 chan->last_acked_seq = control->reqseq;
1093 __clear_ack_timer(chan);
1094 }
1095
1096 BT_DBG("reqseq %d, final %d, poll %d, super %d", control->reqseq,
1097 control->final, control->poll, control->super);
1098
1099 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
1100 control_field = __pack_extended_control(control);
1101 else
1102 control_field = __pack_enhanced_control(control);
1103
1104 skb = l2cap_create_sframe_pdu(chan, control_field);
1105 if (!IS_ERR(skb))
1106 l2cap_do_send(chan, skb);
1107}
1108
1109static void l2cap_send_rr_or_rnr(struct l2cap_chan *chan, bool poll)
1110{
1111 struct l2cap_ctrl control;
1112
1113 BT_DBG("chan %p, poll %d", chan, poll);
1114
1115 memset(&control, 0, sizeof(control));
1116 control.sframe = 1;
1117 control.poll = poll;
1118
1119 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state))
1120 control.super = L2CAP_SUPER_RNR;
1121 else
1122 control.super = L2CAP_SUPER_RR;
1123
1124 control.reqseq = chan->buffer_seq;
1125 l2cap_send_sframe(chan, &control);
1126}
1127
1128static inline int __l2cap_no_conn_pending(struct l2cap_chan *chan)
1129{
1130 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED)
1131 return true;
1132
1133 return !test_bit(CONF_CONNECT_PEND, &chan->conf_state);
1134}
1135
1136static bool __amp_capable(struct l2cap_chan *chan)
1137{
1138 struct l2cap_conn *conn = chan->conn;
1139 struct hci_dev *hdev;
1140 bool amp_available = false;
1141
1142 if (!(conn->local_fixed_chan & L2CAP_FC_A2MP))
1143 return false;
1144
1145 if (!(conn->remote_fixed_chan & L2CAP_FC_A2MP))
1146 return false;
1147
1148 read_lock(&hci_dev_list_lock);
1149 list_for_each_entry(hdev, &hci_dev_list, list) {
1150 if (hdev->amp_type != AMP_TYPE_BREDR &&
1151 test_bit(HCI_UP, &hdev->flags)) {
1152 amp_available = true;
1153 break;
1154 }
1155 }
1156 read_unlock(&hci_dev_list_lock);
1157
1158 if (chan->chan_policy == BT_CHANNEL_POLICY_AMP_PREFERRED)
1159 return amp_available;
1160
1161 return false;
1162}
1163
1164static bool l2cap_check_efs(struct l2cap_chan *chan)
1165{
1166 /* Check EFS parameters */
1167 return true;
1168}
1169
1170void l2cap_send_conn_req(struct l2cap_chan *chan)
1171{
1172 struct l2cap_conn *conn = chan->conn;
1173 struct l2cap_conn_req req;
1174
1175 req.scid = cpu_to_le16(chan->scid);
1176 req.psm = chan->psm;
1177
1178 chan->ident = l2cap_get_ident(conn);
1179
1180 set_bit(CONF_CONNECT_PEND, &chan->conf_state);
1181
1182 l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_REQ, sizeof(req), &req);
1183}
1184
1185static void l2cap_send_create_chan_req(struct l2cap_chan *chan, u8 amp_id)
1186{
1187 struct l2cap_create_chan_req req;
1188 req.scid = cpu_to_le16(chan->scid);
1189 req.psm = chan->psm;
1190 req.amp_id = amp_id;
1191
1192 chan->ident = l2cap_get_ident(chan->conn);
1193
1194 l2cap_send_cmd(chan->conn, chan->ident, L2CAP_CREATE_CHAN_REQ,
1195 sizeof(req), &req);
1196}
1197
1198static void l2cap_move_setup(struct l2cap_chan *chan)
1199{
1200 struct sk_buff *skb;
1201
1202 BT_DBG("chan %p", chan);
1203
1204 if (chan->mode != L2CAP_MODE_ERTM)
1205 return;
1206
1207 __clear_retrans_timer(chan);
1208 __clear_monitor_timer(chan);
1209 __clear_ack_timer(chan);
1210
1211 chan->retry_count = 0;
1212 skb_queue_walk(&chan->tx_q, skb) {
1213 if (bt_cb(skb)->l2cap.retries)
1214 bt_cb(skb)->l2cap.retries = 1;
1215 else
1216 break;
1217 }
1218
1219 chan->expected_tx_seq = chan->buffer_seq;
1220
1221 clear_bit(CONN_REJ_ACT, &chan->conn_state);
1222 clear_bit(CONN_SREJ_ACT, &chan->conn_state);
1223 l2cap_seq_list_clear(&chan->retrans_list);
1224 l2cap_seq_list_clear(&chan->srej_list);
1225 skb_queue_purge(&chan->srej_q);
1226
1227 chan->tx_state = L2CAP_TX_STATE_XMIT;
1228 chan->rx_state = L2CAP_RX_STATE_MOVE;
1229
1230 set_bit(CONN_REMOTE_BUSY, &chan->conn_state);
1231}
1232
1233static void l2cap_move_done(struct l2cap_chan *chan)
1234{
1235 u8 move_role = chan->move_role;
1236 BT_DBG("chan %p", chan);
1237
1238 chan->move_state = L2CAP_MOVE_STABLE;
1239 chan->move_role = L2CAP_MOVE_ROLE_NONE;
1240
1241 if (chan->mode != L2CAP_MODE_ERTM)
1242 return;
1243
1244 switch (move_role) {
1245 case L2CAP_MOVE_ROLE_INITIATOR:
1246 l2cap_tx(chan, NULL, NULL, L2CAP_EV_EXPLICIT_POLL);
1247 chan->rx_state = L2CAP_RX_STATE_WAIT_F;
1248 break;
1249 case L2CAP_MOVE_ROLE_RESPONDER:
1250 chan->rx_state = L2CAP_RX_STATE_WAIT_P;
1251 break;
1252 }
1253}
1254
1255static void l2cap_chan_ready(struct l2cap_chan *chan)
1256{
1257 /* The channel may have already been flagged as connected in
1258 * case of receiving data before the L2CAP info req/rsp
1259 * procedure is complete.
1260 */
1261 if (chan->state == BT_CONNECTED)
1262 return;
1263
1264 /* This clears all conf flags, including CONF_NOT_COMPLETE */
1265 chan->conf_state = 0;
1266 __clear_chan_timer(chan);
1267
1268 if (chan->mode == L2CAP_MODE_LE_FLOWCTL && !chan->tx_credits)
1269 chan->ops->suspend(chan);
1270
1271 chan->state = BT_CONNECTED;
1272
1273 chan->ops->ready(chan);
1274}
1275
1276static void l2cap_le_connect(struct l2cap_chan *chan)
1277{
1278 struct l2cap_conn *conn = chan->conn;
1279 struct l2cap_le_conn_req req;
1280
1281 if (test_and_set_bit(FLAG_LE_CONN_REQ_SENT, &chan->flags))
1282 return;
1283
1284 req.psm = chan->psm;
1285 req.scid = cpu_to_le16(chan->scid);
1286 req.mtu = cpu_to_le16(chan->imtu);
1287 req.mps = cpu_to_le16(chan->mps);
1288 req.credits = cpu_to_le16(chan->rx_credits);
1289
1290 chan->ident = l2cap_get_ident(conn);
1291
1292 l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CONN_REQ,
1293 sizeof(req), &req);
1294}
1295
1296static void l2cap_le_start(struct l2cap_chan *chan)
1297{
1298 struct l2cap_conn *conn = chan->conn;
1299
1300 if (!smp_conn_security(conn->hcon, chan->sec_level))
1301 return;
1302
1303 if (!chan->psm) {
1304 l2cap_chan_ready(chan);
1305 return;
1306 }
1307
1308 if (chan->state == BT_CONNECT)
1309 l2cap_le_connect(chan);
1310}
1311
1312static void l2cap_start_connection(struct l2cap_chan *chan)
1313{
1314 if (__amp_capable(chan)) {
1315 BT_DBG("chan %p AMP capable: discover AMPs", chan);
1316 a2mp_discover_amp(chan);
1317 } else if (chan->conn->hcon->type == LE_LINK) {
1318 l2cap_le_start(chan);
1319 } else {
1320 l2cap_send_conn_req(chan);
1321 }
1322}
1323
1324static void l2cap_request_info(struct l2cap_conn *conn)
1325{
1326 struct l2cap_info_req req;
1327
1328 if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT)
1329 return;
1330
1331 req.type = cpu_to_le16(L2CAP_IT_FEAT_MASK);
1332
1333 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_SENT;
1334 conn->info_ident = l2cap_get_ident(conn);
1335
1336 schedule_delayed_work(&conn->info_timer, L2CAP_INFO_TIMEOUT);
1337
1338 l2cap_send_cmd(conn, conn->info_ident, L2CAP_INFO_REQ,
1339 sizeof(req), &req);
1340}
1341
1342static void l2cap_do_start(struct l2cap_chan *chan)
1343{
1344 struct l2cap_conn *conn = chan->conn;
1345
1346 if (conn->hcon->type == LE_LINK) {
1347 l2cap_le_start(chan);
1348 return;
1349 }
1350
1351 if (!(conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT)) {
1352 l2cap_request_info(conn);
1353 return;
1354 }
1355
1356 if (!(conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE))
1357 return;
1358
1359 if (l2cap_chan_check_security(chan, true) &&
1360 __l2cap_no_conn_pending(chan))
1361 l2cap_start_connection(chan);
1362}
1363
1364static inline int l2cap_mode_supported(__u8 mode, __u32 feat_mask)
1365{
1366 u32 local_feat_mask = l2cap_feat_mask;
1367 if (!disable_ertm)
1368 local_feat_mask |= L2CAP_FEAT_ERTM | L2CAP_FEAT_STREAMING;
1369
1370 switch (mode) {
1371 case L2CAP_MODE_ERTM:
1372 return L2CAP_FEAT_ERTM & feat_mask & local_feat_mask;
1373 case L2CAP_MODE_STREAMING:
1374 return L2CAP_FEAT_STREAMING & feat_mask & local_feat_mask;
1375 default:
1376 return 0x00;
1377 }
1378}
1379
1380static void l2cap_send_disconn_req(struct l2cap_chan *chan, int err)
1381{
1382 struct l2cap_conn *conn = chan->conn;
1383 struct l2cap_disconn_req req;
1384
1385 if (!conn)
1386 return;
1387
1388 if (chan->mode == L2CAP_MODE_ERTM && chan->state == BT_CONNECTED) {
1389 __clear_retrans_timer(chan);
1390 __clear_monitor_timer(chan);
1391 __clear_ack_timer(chan);
1392 }
1393
1394 if (chan->scid == L2CAP_CID_A2MP) {
1395 l2cap_state_change(chan, BT_DISCONN);
1396 return;
1397 }
1398
1399 req.dcid = cpu_to_le16(chan->dcid);
1400 req.scid = cpu_to_le16(chan->scid);
1401 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_DISCONN_REQ,
1402 sizeof(req), &req);
1403
1404 l2cap_state_change_and_error(chan, BT_DISCONN, err);
1405}
1406
1407/* ---- L2CAP connections ---- */
1408static void l2cap_conn_start(struct l2cap_conn *conn)
1409{
1410 struct l2cap_chan *chan, *tmp;
1411
1412 BT_DBG("conn %p", conn);
1413
1414 mutex_lock(&conn->chan_lock);
1415
1416 list_for_each_entry_safe(chan, tmp, &conn->chan_l, list) {
1417 l2cap_chan_lock(chan);
1418
1419 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) {
1420 l2cap_chan_ready(chan);
1421 l2cap_chan_unlock(chan);
1422 continue;
1423 }
1424
1425 if (chan->state == BT_CONNECT) {
1426 if (!l2cap_chan_check_security(chan, true) ||
1427 !__l2cap_no_conn_pending(chan)) {
1428 l2cap_chan_unlock(chan);
1429 continue;
1430 }
1431
1432 if (!l2cap_mode_supported(chan->mode, conn->feat_mask)
1433 && test_bit(CONF_STATE2_DEVICE,
1434 &chan->conf_state)) {
1435 l2cap_chan_close(chan, ECONNRESET);
1436 l2cap_chan_unlock(chan);
1437 continue;
1438 }
1439
1440 l2cap_start_connection(chan);
1441
1442 } else if (chan->state == BT_CONNECT2) {
1443 struct l2cap_conn_rsp rsp;
1444 char buf[128];
1445 rsp.scid = cpu_to_le16(chan->dcid);
1446 rsp.dcid = cpu_to_le16(chan->scid);
1447
1448 if (l2cap_chan_check_security(chan, false)) {
1449 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) {
1450 rsp.result = cpu_to_le16(L2CAP_CR_PEND);
1451 rsp.status = cpu_to_le16(L2CAP_CS_AUTHOR_PEND);
1452 chan->ops->defer(chan);
1453
1454 } else {
1455 l2cap_state_change(chan, BT_CONFIG);
1456 rsp.result = cpu_to_le16(L2CAP_CR_SUCCESS);
1457 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
1458 }
1459 } else {
1460 rsp.result = cpu_to_le16(L2CAP_CR_PEND);
1461 rsp.status = cpu_to_le16(L2CAP_CS_AUTHEN_PEND);
1462 }
1463
1464 l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_RSP,
1465 sizeof(rsp), &rsp);
1466
1467 if (test_bit(CONF_REQ_SENT, &chan->conf_state) ||
1468 rsp.result != L2CAP_CR_SUCCESS) {
1469 l2cap_chan_unlock(chan);
1470 continue;
1471 }
1472
1473 set_bit(CONF_REQ_SENT, &chan->conf_state);
1474 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
1475 l2cap_build_conf_req(chan, buf), buf);
1476 chan->num_conf_req++;
1477 }
1478
1479 l2cap_chan_unlock(chan);
1480 }
1481
1482 mutex_unlock(&conn->chan_lock);
1483}
1484
1485static void l2cap_le_conn_ready(struct l2cap_conn *conn)
1486{
1487 struct hci_conn *hcon = conn->hcon;
1488 struct hci_dev *hdev = hcon->hdev;
1489
1490 BT_DBG("%s conn %p", hdev->name, conn);
1491
1492 /* For outgoing pairing which doesn't necessarily have an
1493 * associated socket (e.g. mgmt_pair_device).
1494 */
1495 if (hcon->out)
1496 smp_conn_security(hcon, hcon->pending_sec_level);
1497
1498 /* For LE slave connections, make sure the connection interval
1499 * is in the range of the minium and maximum interval that has
1500 * been configured for this connection. If not, then trigger
1501 * the connection update procedure.
1502 */
1503 if (hcon->role == HCI_ROLE_SLAVE &&
1504 (hcon->le_conn_interval < hcon->le_conn_min_interval ||
1505 hcon->le_conn_interval > hcon->le_conn_max_interval)) {
1506 struct l2cap_conn_param_update_req req;
1507
1508 req.min = cpu_to_le16(hcon->le_conn_min_interval);
1509 req.max = cpu_to_le16(hcon->le_conn_max_interval);
1510 req.latency = cpu_to_le16(hcon->le_conn_latency);
1511 req.to_multiplier = cpu_to_le16(hcon->le_supv_timeout);
1512
1513 l2cap_send_cmd(conn, l2cap_get_ident(conn),
1514 L2CAP_CONN_PARAM_UPDATE_REQ, sizeof(req), &req);
1515 }
1516}
1517
1518static void l2cap_conn_ready(struct l2cap_conn *conn)
1519{
1520 struct l2cap_chan *chan;
1521 struct hci_conn *hcon = conn->hcon;
1522
1523 BT_DBG("conn %p", conn);
1524
1525 if (hcon->type == ACL_LINK)
1526 l2cap_request_info(conn);
1527
1528 mutex_lock(&conn->chan_lock);
1529
1530 list_for_each_entry(chan, &conn->chan_l, list) {
1531
1532 l2cap_chan_lock(chan);
1533
1534 if (chan->scid == L2CAP_CID_A2MP) {
1535 l2cap_chan_unlock(chan);
1536 continue;
1537 }
1538
1539 if (hcon->type == LE_LINK) {
1540 l2cap_le_start(chan);
1541 } else if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) {
1542 if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE)
1543 l2cap_chan_ready(chan);
1544 } else if (chan->state == BT_CONNECT) {
1545 l2cap_do_start(chan);
1546 }
1547
1548 l2cap_chan_unlock(chan);
1549 }
1550
1551 mutex_unlock(&conn->chan_lock);
1552
1553 if (hcon->type == LE_LINK)
1554 l2cap_le_conn_ready(conn);
1555
1556 queue_work(hcon->hdev->workqueue, &conn->pending_rx_work);
1557}
1558
1559/* Notify sockets that we cannot guaranty reliability anymore */
1560static void l2cap_conn_unreliable(struct l2cap_conn *conn, int err)
1561{
1562 struct l2cap_chan *chan;
1563
1564 BT_DBG("conn %p", conn);
1565
1566 mutex_lock(&conn->chan_lock);
1567
1568 list_for_each_entry(chan, &conn->chan_l, list) {
1569 if (test_bit(FLAG_FORCE_RELIABLE, &chan->flags))
1570 l2cap_chan_set_err(chan, err);
1571 }
1572
1573 mutex_unlock(&conn->chan_lock);
1574}
1575
1576static void l2cap_info_timeout(struct work_struct *work)
1577{
1578 struct l2cap_conn *conn = container_of(work, struct l2cap_conn,
1579 info_timer.work);
1580
1581 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
1582 conn->info_ident = 0;
1583
1584 l2cap_conn_start(conn);
1585}
1586
1587/*
1588 * l2cap_user
1589 * External modules can register l2cap_user objects on l2cap_conn. The ->probe
1590 * callback is called during registration. The ->remove callback is called
1591 * during unregistration.
1592 * An l2cap_user object can either be explicitly unregistered or when the
1593 * underlying l2cap_conn object is deleted. This guarantees that l2cap->hcon,
1594 * l2cap->hchan, .. are valid as long as the remove callback hasn't been called.
1595 * External modules must own a reference to the l2cap_conn object if they intend
1596 * to call l2cap_unregister_user(). The l2cap_conn object might get destroyed at
1597 * any time if they don't.
1598 */
1599
1600int l2cap_register_user(struct l2cap_conn *conn, struct l2cap_user *user)
1601{
1602 struct hci_dev *hdev = conn->hcon->hdev;
1603 int ret;
1604
1605 /* We need to check whether l2cap_conn is registered. If it is not, we
1606 * must not register the l2cap_user. l2cap_conn_del() is unregisters
1607 * l2cap_conn objects, but doesn't provide its own locking. Instead, it
1608 * relies on the parent hci_conn object to be locked. This itself relies
1609 * on the hci_dev object to be locked. So we must lock the hci device
1610 * here, too. */
1611
1612 hci_dev_lock(hdev);
1613
1614 if (!list_empty(&user->list)) {
1615 ret = -EINVAL;
1616 goto out_unlock;
1617 }
1618
1619 /* conn->hchan is NULL after l2cap_conn_del() was called */
1620 if (!conn->hchan) {
1621 ret = -ENODEV;
1622 goto out_unlock;
1623 }
1624
1625 ret = user->probe(conn, user);
1626 if (ret)
1627 goto out_unlock;
1628
1629 list_add(&user->list, &conn->users);
1630 ret = 0;
1631
1632out_unlock:
1633 hci_dev_unlock(hdev);
1634 return ret;
1635}
1636EXPORT_SYMBOL(l2cap_register_user);
1637
1638void l2cap_unregister_user(struct l2cap_conn *conn, struct l2cap_user *user)
1639{
1640 struct hci_dev *hdev = conn->hcon->hdev;
1641
1642 hci_dev_lock(hdev);
1643
1644 if (list_empty(&user->list))
1645 goto out_unlock;
1646
1647 list_del_init(&user->list);
1648 user->remove(conn, user);
1649
1650out_unlock:
1651 hci_dev_unlock(hdev);
1652}
1653EXPORT_SYMBOL(l2cap_unregister_user);
1654
1655static void l2cap_unregister_all_users(struct l2cap_conn *conn)
1656{
1657 struct l2cap_user *user;
1658
1659 while (!list_empty(&conn->users)) {
1660 user = list_first_entry(&conn->users, struct l2cap_user, list);
1661 list_del_init(&user->list);
1662 user->remove(conn, user);
1663 }
1664}
1665
1666static void l2cap_conn_del(struct hci_conn *hcon, int err)
1667{
1668 struct l2cap_conn *conn = hcon->l2cap_data;
1669 struct l2cap_chan *chan, *l;
1670
1671 if (!conn)
1672 return;
1673
1674 BT_DBG("hcon %p conn %p, err %d", hcon, conn, err);
1675
1676 kfree_skb(conn->rx_skb);
1677
1678 skb_queue_purge(&conn->pending_rx);
1679
1680 /* We can not call flush_work(&conn->pending_rx_work) here since we
1681 * might block if we are running on a worker from the same workqueue
1682 * pending_rx_work is waiting on.
1683 */
1684 if (work_pending(&conn->pending_rx_work))
1685 cancel_work_sync(&conn->pending_rx_work);
1686
1687 if (work_pending(&conn->id_addr_update_work))
1688 cancel_work_sync(&conn->id_addr_update_work);
1689
1690 l2cap_unregister_all_users(conn);
1691
1692 /* Force the connection to be immediately dropped */
1693 hcon->disc_timeout = 0;
1694
1695 mutex_lock(&conn->chan_lock);
1696
1697 /* Kill channels */
1698 list_for_each_entry_safe(chan, l, &conn->chan_l, list) {
1699 l2cap_chan_hold(chan);
1700 l2cap_chan_lock(chan);
1701
1702 l2cap_chan_del(chan, err);
1703
1704 l2cap_chan_unlock(chan);
1705
1706 chan->ops->close(chan);
1707 l2cap_chan_put(chan);
1708 }
1709
1710 mutex_unlock(&conn->chan_lock);
1711
1712 hci_chan_del(conn->hchan);
1713
1714 if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT)
1715 cancel_delayed_work_sync(&conn->info_timer);
1716
1717 hcon->l2cap_data = NULL;
1718 conn->hchan = NULL;
1719 l2cap_conn_put(conn);
1720}
1721
1722static void l2cap_conn_free(struct kref *ref)
1723{
1724 struct l2cap_conn *conn = container_of(ref, struct l2cap_conn, ref);
1725
1726 hci_conn_put(conn->hcon);
1727 kfree(conn);
1728}
1729
1730struct l2cap_conn *l2cap_conn_get(struct l2cap_conn *conn)
1731{
1732 kref_get(&conn->ref);
1733 return conn;
1734}
1735EXPORT_SYMBOL(l2cap_conn_get);
1736
1737void l2cap_conn_put(struct l2cap_conn *conn)
1738{
1739 kref_put(&conn->ref, l2cap_conn_free);
1740}
1741EXPORT_SYMBOL(l2cap_conn_put);
1742
1743/* ---- Socket interface ---- */
1744
1745/* Find socket with psm and source / destination bdaddr.
1746 * Returns closest match.
1747 */
1748static struct l2cap_chan *l2cap_global_chan_by_psm(int state, __le16 psm,
1749 bdaddr_t *src,
1750 bdaddr_t *dst,
1751 u8 link_type)
1752{
1753 struct l2cap_chan *c, *c1 = NULL;
1754
1755 read_lock(&chan_list_lock);
1756
1757 list_for_each_entry(c, &chan_list, global_l) {
1758 if (state && c->state != state)
1759 continue;
1760
1761 if (link_type == ACL_LINK && c->src_type != BDADDR_BREDR)
1762 continue;
1763
1764 if (link_type == LE_LINK && c->src_type == BDADDR_BREDR)
1765 continue;
1766
1767 if (c->psm == psm) {
1768 int src_match, dst_match;
1769 int src_any, dst_any;
1770
1771 /* Exact match. */
1772 src_match = !bacmp(&c->src, src);
1773 dst_match = !bacmp(&c->dst, dst);
1774 if (src_match && dst_match) {
1775 l2cap_chan_hold(c);
1776 read_unlock(&chan_list_lock);
1777 return c;
1778 }
1779
1780 /* Closest match */
1781 src_any = !bacmp(&c->src, BDADDR_ANY);
1782 dst_any = !bacmp(&c->dst, BDADDR_ANY);
1783 if ((src_match && dst_any) || (src_any && dst_match) ||
1784 (src_any && dst_any))
1785 c1 = c;
1786 }
1787 }
1788
1789 if (c1)
1790 l2cap_chan_hold(c1);
1791
1792 read_unlock(&chan_list_lock);
1793
1794 return c1;
1795}
1796
1797static void l2cap_monitor_timeout(struct work_struct *work)
1798{
1799 struct l2cap_chan *chan = container_of(work, struct l2cap_chan,
1800 monitor_timer.work);
1801
1802 BT_DBG("chan %p", chan);
1803
1804 l2cap_chan_lock(chan);
1805
1806 if (!chan->conn) {
1807 l2cap_chan_unlock(chan);
1808 l2cap_chan_put(chan);
1809 return;
1810 }
1811
1812 l2cap_tx(chan, NULL, NULL, L2CAP_EV_MONITOR_TO);
1813
1814 l2cap_chan_unlock(chan);
1815 l2cap_chan_put(chan);
1816}
1817
1818static void l2cap_retrans_timeout(struct work_struct *work)
1819{
1820 struct l2cap_chan *chan = container_of(work, struct l2cap_chan,
1821 retrans_timer.work);
1822
1823 BT_DBG("chan %p", chan);
1824
1825 l2cap_chan_lock(chan);
1826
1827 if (!chan->conn) {
1828 l2cap_chan_unlock(chan);
1829 l2cap_chan_put(chan);
1830 return;
1831 }
1832
1833 l2cap_tx(chan, NULL, NULL, L2CAP_EV_RETRANS_TO);
1834 l2cap_chan_unlock(chan);
1835 l2cap_chan_put(chan);
1836}
1837
1838static void l2cap_streaming_send(struct l2cap_chan *chan,
1839 struct sk_buff_head *skbs)
1840{
1841 struct sk_buff *skb;
1842 struct l2cap_ctrl *control;
1843
1844 BT_DBG("chan %p, skbs %p", chan, skbs);
1845
1846 if (__chan_is_moving(chan))
1847 return;
1848
1849 skb_queue_splice_tail_init(skbs, &chan->tx_q);
1850
1851 while (!skb_queue_empty(&chan->tx_q)) {
1852
1853 skb = skb_dequeue(&chan->tx_q);
1854
1855 bt_cb(skb)->l2cap.retries = 1;
1856 control = &bt_cb(skb)->l2cap;
1857
1858 control->reqseq = 0;
1859 control->txseq = chan->next_tx_seq;
1860
1861 __pack_control(chan, control, skb);
1862
1863 if (chan->fcs == L2CAP_FCS_CRC16) {
1864 u16 fcs = crc16(0, (u8 *) skb->data, skb->len);
1865 put_unaligned_le16(fcs, skb_put(skb, L2CAP_FCS_SIZE));
1866 }
1867
1868 l2cap_do_send(chan, skb);
1869
1870 BT_DBG("Sent txseq %u", control->txseq);
1871
1872 chan->next_tx_seq = __next_seq(chan, chan->next_tx_seq);
1873 chan->frames_sent++;
1874 }
1875}
1876
1877static int l2cap_ertm_send(struct l2cap_chan *chan)
1878{
1879 struct sk_buff *skb, *tx_skb;
1880 struct l2cap_ctrl *control;
1881 int sent = 0;
1882
1883 BT_DBG("chan %p", chan);
1884
1885 if (chan->state != BT_CONNECTED)
1886 return -ENOTCONN;
1887
1888 if (test_bit(CONN_REMOTE_BUSY, &chan->conn_state))
1889 return 0;
1890
1891 if (__chan_is_moving(chan))
1892 return 0;
1893
1894 while (chan->tx_send_head &&
1895 chan->unacked_frames < chan->remote_tx_win &&
1896 chan->tx_state == L2CAP_TX_STATE_XMIT) {
1897
1898 skb = chan->tx_send_head;
1899
1900 bt_cb(skb)->l2cap.retries = 1;
1901 control = &bt_cb(skb)->l2cap;
1902
1903 if (test_and_clear_bit(CONN_SEND_FBIT, &chan->conn_state))
1904 control->final = 1;
1905
1906 control->reqseq = chan->buffer_seq;
1907 chan->last_acked_seq = chan->buffer_seq;
1908 control->txseq = chan->next_tx_seq;
1909
1910 __pack_control(chan, control, skb);
1911
1912 if (chan->fcs == L2CAP_FCS_CRC16) {
1913 u16 fcs = crc16(0, (u8 *) skb->data, skb->len);
1914 put_unaligned_le16(fcs, skb_put(skb, L2CAP_FCS_SIZE));
1915 }
1916
1917 /* Clone after data has been modified. Data is assumed to be
1918 read-only (for locking purposes) on cloned sk_buffs.
1919 */
1920 tx_skb = skb_clone(skb, GFP_KERNEL);
1921
1922 if (!tx_skb)
1923 break;
1924
1925 __set_retrans_timer(chan);
1926
1927 chan->next_tx_seq = __next_seq(chan, chan->next_tx_seq);
1928 chan->unacked_frames++;
1929 chan->frames_sent++;
1930 sent++;
1931
1932 if (skb_queue_is_last(&chan->tx_q, skb))
1933 chan->tx_send_head = NULL;
1934 else
1935 chan->tx_send_head = skb_queue_next(&chan->tx_q, skb);
1936
1937 l2cap_do_send(chan, tx_skb);
1938 BT_DBG("Sent txseq %u", control->txseq);
1939 }
1940
1941 BT_DBG("Sent %d, %u unacked, %u in ERTM queue", sent,
1942 chan->unacked_frames, skb_queue_len(&chan->tx_q));
1943
1944 return sent;
1945}
1946
1947static void l2cap_ertm_resend(struct l2cap_chan *chan)
1948{
1949 struct l2cap_ctrl control;
1950 struct sk_buff *skb;
1951 struct sk_buff *tx_skb;
1952 u16 seq;
1953
1954 BT_DBG("chan %p", chan);
1955
1956 if (test_bit(CONN_REMOTE_BUSY, &chan->conn_state))
1957 return;
1958
1959 if (__chan_is_moving(chan))
1960 return;
1961
1962 while (chan->retrans_list.head != L2CAP_SEQ_LIST_CLEAR) {
1963 seq = l2cap_seq_list_pop(&chan->retrans_list);
1964
1965 skb = l2cap_ertm_seq_in_queue(&chan->tx_q, seq);
1966 if (!skb) {
1967 BT_DBG("Error: Can't retransmit seq %d, frame missing",
1968 seq);
1969 continue;
1970 }
1971
1972 bt_cb(skb)->l2cap.retries++;
1973 control = bt_cb(skb)->l2cap;
1974
1975 if (chan->max_tx != 0 &&
1976 bt_cb(skb)->l2cap.retries > chan->max_tx) {
1977 BT_DBG("Retry limit exceeded (%d)", chan->max_tx);
1978 l2cap_send_disconn_req(chan, ECONNRESET);
1979 l2cap_seq_list_clear(&chan->retrans_list);
1980 break;
1981 }
1982
1983 control.reqseq = chan->buffer_seq;
1984 if (test_and_clear_bit(CONN_SEND_FBIT, &chan->conn_state))
1985 control.final = 1;
1986 else
1987 control.final = 0;
1988
1989 if (skb_cloned(skb)) {
1990 /* Cloned sk_buffs are read-only, so we need a
1991 * writeable copy
1992 */
1993 tx_skb = skb_copy(skb, GFP_KERNEL);
1994 } else {
1995 tx_skb = skb_clone(skb, GFP_KERNEL);
1996 }
1997
1998 if (!tx_skb) {
1999 l2cap_seq_list_clear(&chan->retrans_list);
2000 break;
2001 }
2002
2003 /* Update skb contents */
2004 if (test_bit(FLAG_EXT_CTRL, &chan->flags)) {
2005 put_unaligned_le32(__pack_extended_control(&control),
2006 tx_skb->data + L2CAP_HDR_SIZE);
2007 } else {
2008 put_unaligned_le16(__pack_enhanced_control(&control),
2009 tx_skb->data + L2CAP_HDR_SIZE);
2010 }
2011
2012 /* Update FCS */
2013 if (chan->fcs == L2CAP_FCS_CRC16) {
2014 u16 fcs = crc16(0, (u8 *) tx_skb->data,
2015 tx_skb->len - L2CAP_FCS_SIZE);
2016 put_unaligned_le16(fcs, skb_tail_pointer(tx_skb) -
2017 L2CAP_FCS_SIZE);
2018 }
2019
2020 l2cap_do_send(chan, tx_skb);
2021
2022 BT_DBG("Resent txseq %d", control.txseq);
2023
2024 chan->last_acked_seq = chan->buffer_seq;
2025 }
2026}
2027
2028static void l2cap_retransmit(struct l2cap_chan *chan,
2029 struct l2cap_ctrl *control)
2030{
2031 BT_DBG("chan %p, control %p", chan, control);
2032
2033 l2cap_seq_list_append(&chan->retrans_list, control->reqseq);
2034 l2cap_ertm_resend(chan);
2035}
2036
2037static void l2cap_retransmit_all(struct l2cap_chan *chan,
2038 struct l2cap_ctrl *control)
2039{
2040 struct sk_buff *skb;
2041
2042 BT_DBG("chan %p, control %p", chan, control);
2043
2044 if (control->poll)
2045 set_bit(CONN_SEND_FBIT, &chan->conn_state);
2046
2047 l2cap_seq_list_clear(&chan->retrans_list);
2048
2049 if (test_bit(CONN_REMOTE_BUSY, &chan->conn_state))
2050 return;
2051
2052 if (chan->unacked_frames) {
2053 skb_queue_walk(&chan->tx_q, skb) {
2054 if (bt_cb(skb)->l2cap.txseq == control->reqseq ||
2055 skb == chan->tx_send_head)
2056 break;
2057 }
2058
2059 skb_queue_walk_from(&chan->tx_q, skb) {
2060 if (skb == chan->tx_send_head)
2061 break;
2062
2063 l2cap_seq_list_append(&chan->retrans_list,
2064 bt_cb(skb)->l2cap.txseq);
2065 }
2066
2067 l2cap_ertm_resend(chan);
2068 }
2069}
2070
2071static void l2cap_send_ack(struct l2cap_chan *chan)
2072{
2073 struct l2cap_ctrl control;
2074 u16 frames_to_ack = __seq_offset(chan, chan->buffer_seq,
2075 chan->last_acked_seq);
2076 int threshold;
2077
2078 BT_DBG("chan %p last_acked_seq %d buffer_seq %d",
2079 chan, chan->last_acked_seq, chan->buffer_seq);
2080
2081 memset(&control, 0, sizeof(control));
2082 control.sframe = 1;
2083
2084 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state) &&
2085 chan->rx_state == L2CAP_RX_STATE_RECV) {
2086 __clear_ack_timer(chan);
2087 control.super = L2CAP_SUPER_RNR;
2088 control.reqseq = chan->buffer_seq;
2089 l2cap_send_sframe(chan, &control);
2090 } else {
2091 if (!test_bit(CONN_REMOTE_BUSY, &chan->conn_state)) {
2092 l2cap_ertm_send(chan);
2093 /* If any i-frames were sent, they included an ack */
2094 if (chan->buffer_seq == chan->last_acked_seq)
2095 frames_to_ack = 0;
2096 }
2097
2098 /* Ack now if the window is 3/4ths full.
2099 * Calculate without mul or div
2100 */
2101 threshold = chan->ack_win;
2102 threshold += threshold << 1;
2103 threshold >>= 2;
2104
2105 BT_DBG("frames_to_ack %u, threshold %d", frames_to_ack,
2106 threshold);
2107
2108 if (frames_to_ack >= threshold) {
2109 __clear_ack_timer(chan);
2110 control.super = L2CAP_SUPER_RR;
2111 control.reqseq = chan->buffer_seq;
2112 l2cap_send_sframe(chan, &control);
2113 frames_to_ack = 0;
2114 }
2115
2116 if (frames_to_ack)
2117 __set_ack_timer(chan);
2118 }
2119}
2120
2121static inline int l2cap_skbuff_fromiovec(struct l2cap_chan *chan,
2122 struct msghdr *msg, int len,
2123 int count, struct sk_buff *skb)
2124{
2125 struct l2cap_conn *conn = chan->conn;
2126 struct sk_buff **frag;
2127 int sent = 0;
2128
2129 if (copy_from_iter(skb_put(skb, count), count, &msg->msg_iter) != count)
2130 return -EFAULT;
2131
2132 sent += count;
2133 len -= count;
2134
2135 /* Continuation fragments (no L2CAP header) */
2136 frag = &skb_shinfo(skb)->frag_list;
2137 while (len) {
2138 struct sk_buff *tmp;
2139
2140 count = min_t(unsigned int, conn->mtu, len);
2141
2142 tmp = chan->ops->alloc_skb(chan, 0, count,
2143 msg->msg_flags & MSG_DONTWAIT);
2144 if (IS_ERR(tmp))
2145 return PTR_ERR(tmp);
2146
2147 *frag = tmp;
2148
2149 if (copy_from_iter(skb_put(*frag, count), count,
2150 &msg->msg_iter) != count)
2151 return -EFAULT;
2152
2153 sent += count;
2154 len -= count;
2155
2156 skb->len += (*frag)->len;
2157 skb->data_len += (*frag)->len;
2158
2159 frag = &(*frag)->next;
2160 }
2161
2162 return sent;
2163}
2164
2165static struct sk_buff *l2cap_create_connless_pdu(struct l2cap_chan *chan,
2166 struct msghdr *msg, size_t len)
2167{
2168 struct l2cap_conn *conn = chan->conn;
2169 struct sk_buff *skb;
2170 int err, count, hlen = L2CAP_HDR_SIZE + L2CAP_PSMLEN_SIZE;
2171 struct l2cap_hdr *lh;
2172
2173 BT_DBG("chan %p psm 0x%2.2x len %zu", chan,
2174 __le16_to_cpu(chan->psm), len);
2175
2176 count = min_t(unsigned int, (conn->mtu - hlen), len);
2177
2178 skb = chan->ops->alloc_skb(chan, hlen, count,
2179 msg->msg_flags & MSG_DONTWAIT);
2180 if (IS_ERR(skb))
2181 return skb;
2182
2183 /* Create L2CAP header */
2184 lh = (struct l2cap_hdr *) skb_put(skb, L2CAP_HDR_SIZE);
2185 lh->cid = cpu_to_le16(chan->dcid);
2186 lh->len = cpu_to_le16(len + L2CAP_PSMLEN_SIZE);
2187 put_unaligned(chan->psm, (__le16 *) skb_put(skb, L2CAP_PSMLEN_SIZE));
2188
2189 err = l2cap_skbuff_fromiovec(chan, msg, len, count, skb);
2190 if (unlikely(err < 0)) {
2191 kfree_skb(skb);
2192 return ERR_PTR(err);
2193 }
2194 return skb;
2195}
2196
2197static struct sk_buff *l2cap_create_basic_pdu(struct l2cap_chan *chan,
2198 struct msghdr *msg, size_t len)
2199{
2200 struct l2cap_conn *conn = chan->conn;
2201 struct sk_buff *skb;
2202 int err, count;
2203 struct l2cap_hdr *lh;
2204
2205 BT_DBG("chan %p len %zu", chan, len);
2206
2207 count = min_t(unsigned int, (conn->mtu - L2CAP_HDR_SIZE), len);
2208
2209 skb = chan->ops->alloc_skb(chan, L2CAP_HDR_SIZE, count,
2210 msg->msg_flags & MSG_DONTWAIT);
2211 if (IS_ERR(skb))
2212 return skb;
2213
2214 /* Create L2CAP header */
2215 lh = (struct l2cap_hdr *) skb_put(skb, L2CAP_HDR_SIZE);
2216 lh->cid = cpu_to_le16(chan->dcid);
2217 lh->len = cpu_to_le16(len);
2218
2219 err = l2cap_skbuff_fromiovec(chan, msg, len, count, skb);
2220 if (unlikely(err < 0)) {
2221 kfree_skb(skb);
2222 return ERR_PTR(err);
2223 }
2224 return skb;
2225}
2226
2227static struct sk_buff *l2cap_create_iframe_pdu(struct l2cap_chan *chan,
2228 struct msghdr *msg, size_t len,
2229 u16 sdulen)
2230{
2231 struct l2cap_conn *conn = chan->conn;
2232 struct sk_buff *skb;
2233 int err, count, hlen;
2234 struct l2cap_hdr *lh;
2235
2236 BT_DBG("chan %p len %zu", chan, len);
2237
2238 if (!conn)
2239 return ERR_PTR(-ENOTCONN);
2240
2241 hlen = __ertm_hdr_size(chan);
2242
2243 if (sdulen)
2244 hlen += L2CAP_SDULEN_SIZE;
2245
2246 if (chan->fcs == L2CAP_FCS_CRC16)
2247 hlen += L2CAP_FCS_SIZE;
2248
2249 count = min_t(unsigned int, (conn->mtu - hlen), len);
2250
2251 skb = chan->ops->alloc_skb(chan, hlen, count,
2252 msg->msg_flags & MSG_DONTWAIT);
2253 if (IS_ERR(skb))
2254 return skb;
2255
2256 /* Create L2CAP header */
2257 lh = (struct l2cap_hdr *) skb_put(skb, L2CAP_HDR_SIZE);
2258 lh->cid = cpu_to_le16(chan->dcid);
2259 lh->len = cpu_to_le16(len + (hlen - L2CAP_HDR_SIZE));
2260
2261 /* Control header is populated later */
2262 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
2263 put_unaligned_le32(0, skb_put(skb, L2CAP_EXT_CTRL_SIZE));
2264 else
2265 put_unaligned_le16(0, skb_put(skb, L2CAP_ENH_CTRL_SIZE));
2266
2267 if (sdulen)
2268 put_unaligned_le16(sdulen, skb_put(skb, L2CAP_SDULEN_SIZE));
2269
2270 err = l2cap_skbuff_fromiovec(chan, msg, len, count, skb);
2271 if (unlikely(err < 0)) {
2272 kfree_skb(skb);
2273 return ERR_PTR(err);
2274 }
2275
2276 bt_cb(skb)->l2cap.fcs = chan->fcs;
2277 bt_cb(skb)->l2cap.retries = 0;
2278 return skb;
2279}
2280
2281static int l2cap_segment_sdu(struct l2cap_chan *chan,
2282 struct sk_buff_head *seg_queue,
2283 struct msghdr *msg, size_t len)
2284{
2285 struct sk_buff *skb;
2286 u16 sdu_len;
2287 size_t pdu_len;
2288 u8 sar;
2289
2290 BT_DBG("chan %p, msg %p, len %zu", chan, msg, len);
2291
2292 /* It is critical that ERTM PDUs fit in a single HCI fragment,
2293 * so fragmented skbs are not used. The HCI layer's handling
2294 * of fragmented skbs is not compatible with ERTM's queueing.
2295 */
2296
2297 /* PDU size is derived from the HCI MTU */
2298 pdu_len = chan->conn->mtu;
2299
2300 /* Constrain PDU size for BR/EDR connections */
2301 if (!chan->hs_hcon)
2302 pdu_len = min_t(size_t, pdu_len, L2CAP_BREDR_MAX_PAYLOAD);
2303
2304 /* Adjust for largest possible L2CAP overhead. */
2305 if (chan->fcs)
2306 pdu_len -= L2CAP_FCS_SIZE;
2307
2308 pdu_len -= __ertm_hdr_size(chan);
2309
2310 /* Remote device may have requested smaller PDUs */
2311 pdu_len = min_t(size_t, pdu_len, chan->remote_mps);
2312
2313 if (len <= pdu_len) {
2314 sar = L2CAP_SAR_UNSEGMENTED;
2315 sdu_len = 0;
2316 pdu_len = len;
2317 } else {
2318 sar = L2CAP_SAR_START;
2319 sdu_len = len;
2320 }
2321
2322 while (len > 0) {
2323 skb = l2cap_create_iframe_pdu(chan, msg, pdu_len, sdu_len);
2324
2325 if (IS_ERR(skb)) {
2326 __skb_queue_purge(seg_queue);
2327 return PTR_ERR(skb);
2328 }
2329
2330 bt_cb(skb)->l2cap.sar = sar;
2331 __skb_queue_tail(seg_queue, skb);
2332
2333 len -= pdu_len;
2334 if (sdu_len)
2335 sdu_len = 0;
2336
2337 if (len <= pdu_len) {
2338 sar = L2CAP_SAR_END;
2339 pdu_len = len;
2340 } else {
2341 sar = L2CAP_SAR_CONTINUE;
2342 }
2343 }
2344
2345 return 0;
2346}
2347
2348static struct sk_buff *l2cap_create_le_flowctl_pdu(struct l2cap_chan *chan,
2349 struct msghdr *msg,
2350 size_t len, u16 sdulen)
2351{
2352 struct l2cap_conn *conn = chan->conn;
2353 struct sk_buff *skb;
2354 int err, count, hlen;
2355 struct l2cap_hdr *lh;
2356
2357 BT_DBG("chan %p len %zu", chan, len);
2358
2359 if (!conn)
2360 return ERR_PTR(-ENOTCONN);
2361
2362 hlen = L2CAP_HDR_SIZE;
2363
2364 if (sdulen)
2365 hlen += L2CAP_SDULEN_SIZE;
2366
2367 count = min_t(unsigned int, (conn->mtu - hlen), len);
2368
2369 skb = chan->ops->alloc_skb(chan, hlen, count,
2370 msg->msg_flags & MSG_DONTWAIT);
2371 if (IS_ERR(skb))
2372 return skb;
2373
2374 /* Create L2CAP header */
2375 lh = (struct l2cap_hdr *) skb_put(skb, L2CAP_HDR_SIZE);
2376 lh->cid = cpu_to_le16(chan->dcid);
2377 lh->len = cpu_to_le16(len + (hlen - L2CAP_HDR_SIZE));
2378
2379 if (sdulen)
2380 put_unaligned_le16(sdulen, skb_put(skb, L2CAP_SDULEN_SIZE));
2381
2382 err = l2cap_skbuff_fromiovec(chan, msg, len, count, skb);
2383 if (unlikely(err < 0)) {
2384 kfree_skb(skb);
2385 return ERR_PTR(err);
2386 }
2387
2388 return skb;
2389}
2390
2391static int l2cap_segment_le_sdu(struct l2cap_chan *chan,
2392 struct sk_buff_head *seg_queue,
2393 struct msghdr *msg, size_t len)
2394{
2395 struct sk_buff *skb;
2396 size_t pdu_len;
2397 u16 sdu_len;
2398
2399 BT_DBG("chan %p, msg %p, len %zu", chan, msg, len);
2400
2401 sdu_len = len;
2402 pdu_len = chan->remote_mps - L2CAP_SDULEN_SIZE;
2403
2404 while (len > 0) {
2405 if (len <= pdu_len)
2406 pdu_len = len;
2407
2408 skb = l2cap_create_le_flowctl_pdu(chan, msg, pdu_len, sdu_len);
2409 if (IS_ERR(skb)) {
2410 __skb_queue_purge(seg_queue);
2411 return PTR_ERR(skb);
2412 }
2413
2414 __skb_queue_tail(seg_queue, skb);
2415
2416 len -= pdu_len;
2417
2418 if (sdu_len) {
2419 sdu_len = 0;
2420 pdu_len += L2CAP_SDULEN_SIZE;
2421 }
2422 }
2423
2424 return 0;
2425}
2426
2427int l2cap_chan_send(struct l2cap_chan *chan, struct msghdr *msg, size_t len)
2428{
2429 struct sk_buff *skb;
2430 int err;
2431 struct sk_buff_head seg_queue;
2432
2433 if (!chan->conn)
2434 return -ENOTCONN;
2435
2436 /* Connectionless channel */
2437 if (chan->chan_type == L2CAP_CHAN_CONN_LESS) {
2438 skb = l2cap_create_connless_pdu(chan, msg, len);
2439 if (IS_ERR(skb))
2440 return PTR_ERR(skb);
2441
2442 /* Channel lock is released before requesting new skb and then
2443 * reacquired thus we need to recheck channel state.
2444 */
2445 if (chan->state != BT_CONNECTED) {
2446 kfree_skb(skb);
2447 return -ENOTCONN;
2448 }
2449
2450 l2cap_do_send(chan, skb);
2451 return len;
2452 }
2453
2454 switch (chan->mode) {
2455 case L2CAP_MODE_LE_FLOWCTL:
2456 /* Check outgoing MTU */
2457 if (len > chan->omtu)
2458 return -EMSGSIZE;
2459
2460 if (!chan->tx_credits)
2461 return -EAGAIN;
2462
2463 __skb_queue_head_init(&seg_queue);
2464
2465 err = l2cap_segment_le_sdu(chan, &seg_queue, msg, len);
2466
2467 if (chan->state != BT_CONNECTED) {
2468 __skb_queue_purge(&seg_queue);
2469 err = -ENOTCONN;
2470 }
2471
2472 if (err)
2473 return err;
2474
2475 skb_queue_splice_tail_init(&seg_queue, &chan->tx_q);
2476
2477 while (chan->tx_credits && !skb_queue_empty(&chan->tx_q)) {
2478 l2cap_do_send(chan, skb_dequeue(&chan->tx_q));
2479 chan->tx_credits--;
2480 }
2481
2482 if (!chan->tx_credits)
2483 chan->ops->suspend(chan);
2484
2485 err = len;
2486
2487 break;
2488
2489 case L2CAP_MODE_BASIC:
2490 /* Check outgoing MTU */
2491 if (len > chan->omtu)
2492 return -EMSGSIZE;
2493
2494 /* Create a basic PDU */
2495 skb = l2cap_create_basic_pdu(chan, msg, len);
2496 if (IS_ERR(skb))
2497 return PTR_ERR(skb);
2498
2499 /* Channel lock is released before requesting new skb and then
2500 * reacquired thus we need to recheck channel state.
2501 */
2502 if (chan->state != BT_CONNECTED) {
2503 kfree_skb(skb);
2504 return -ENOTCONN;
2505 }
2506
2507 l2cap_do_send(chan, skb);
2508 err = len;
2509 break;
2510
2511 case L2CAP_MODE_ERTM:
2512 case L2CAP_MODE_STREAMING:
2513 /* Check outgoing MTU */
2514 if (len > chan->omtu) {
2515 err = -EMSGSIZE;
2516 break;
2517 }
2518
2519 __skb_queue_head_init(&seg_queue);
2520
2521 /* Do segmentation before calling in to the state machine,
2522 * since it's possible to block while waiting for memory
2523 * allocation.
2524 */
2525 err = l2cap_segment_sdu(chan, &seg_queue, msg, len);
2526
2527 /* The channel could have been closed while segmenting,
2528 * check that it is still connected.
2529 */
2530 if (chan->state != BT_CONNECTED) {
2531 __skb_queue_purge(&seg_queue);
2532 err = -ENOTCONN;
2533 }
2534
2535 if (err)
2536 break;
2537
2538 if (chan->mode == L2CAP_MODE_ERTM)
2539 l2cap_tx(chan, NULL, &seg_queue, L2CAP_EV_DATA_REQUEST);
2540 else
2541 l2cap_streaming_send(chan, &seg_queue);
2542
2543 err = len;
2544
2545 /* If the skbs were not queued for sending, they'll still be in
2546 * seg_queue and need to be purged.
2547 */
2548 __skb_queue_purge(&seg_queue);
2549 break;
2550
2551 default:
2552 BT_DBG("bad state %1.1x", chan->mode);
2553 err = -EBADFD;
2554 }
2555
2556 return err;
2557}
2558EXPORT_SYMBOL_GPL(l2cap_chan_send);
2559
2560static void l2cap_send_srej(struct l2cap_chan *chan, u16 txseq)
2561{
2562 struct l2cap_ctrl control;
2563 u16 seq;
2564
2565 BT_DBG("chan %p, txseq %u", chan, txseq);
2566
2567 memset(&control, 0, sizeof(control));
2568 control.sframe = 1;
2569 control.super = L2CAP_SUPER_SREJ;
2570
2571 for (seq = chan->expected_tx_seq; seq != txseq;
2572 seq = __next_seq(chan, seq)) {
2573 if (!l2cap_ertm_seq_in_queue(&chan->srej_q, seq)) {
2574 control.reqseq = seq;
2575 l2cap_send_sframe(chan, &control);
2576 l2cap_seq_list_append(&chan->srej_list, seq);
2577 }
2578 }
2579
2580 chan->expected_tx_seq = __next_seq(chan, txseq);
2581}
2582
2583static void l2cap_send_srej_tail(struct l2cap_chan *chan)
2584{
2585 struct l2cap_ctrl control;
2586
2587 BT_DBG("chan %p", chan);
2588
2589 if (chan->srej_list.tail == L2CAP_SEQ_LIST_CLEAR)
2590 return;
2591
2592 memset(&control, 0, sizeof(control));
2593 control.sframe = 1;
2594 control.super = L2CAP_SUPER_SREJ;
2595 control.reqseq = chan->srej_list.tail;
2596 l2cap_send_sframe(chan, &control);
2597}
2598
2599static void l2cap_send_srej_list(struct l2cap_chan *chan, u16 txseq)
2600{
2601 struct l2cap_ctrl control;
2602 u16 initial_head;
2603 u16 seq;
2604
2605 BT_DBG("chan %p, txseq %u", chan, txseq);
2606
2607 memset(&control, 0, sizeof(control));
2608 control.sframe = 1;
2609 control.super = L2CAP_SUPER_SREJ;
2610
2611 /* Capture initial list head to allow only one pass through the list. */
2612 initial_head = chan->srej_list.head;
2613
2614 do {
2615 seq = l2cap_seq_list_pop(&chan->srej_list);
2616 if (seq == txseq || seq == L2CAP_SEQ_LIST_CLEAR)
2617 break;
2618
2619 control.reqseq = seq;
2620 l2cap_send_sframe(chan, &control);
2621 l2cap_seq_list_append(&chan->srej_list, seq);
2622 } while (chan->srej_list.head != initial_head);
2623}
2624
2625static void l2cap_process_reqseq(struct l2cap_chan *chan, u16 reqseq)
2626{
2627 struct sk_buff *acked_skb;
2628 u16 ackseq;
2629
2630 BT_DBG("chan %p, reqseq %u", chan, reqseq);
2631
2632 if (chan->unacked_frames == 0 || reqseq == chan->expected_ack_seq)
2633 return;
2634
2635 BT_DBG("expected_ack_seq %u, unacked_frames %u",
2636 chan->expected_ack_seq, chan->unacked_frames);
2637
2638 for (ackseq = chan->expected_ack_seq; ackseq != reqseq;
2639 ackseq = __next_seq(chan, ackseq)) {
2640
2641 acked_skb = l2cap_ertm_seq_in_queue(&chan->tx_q, ackseq);
2642 if (acked_skb) {
2643 skb_unlink(acked_skb, &chan->tx_q);
2644 kfree_skb(acked_skb);
2645 chan->unacked_frames--;
2646 }
2647 }
2648
2649 chan->expected_ack_seq = reqseq;
2650
2651 if (chan->unacked_frames == 0)
2652 __clear_retrans_timer(chan);
2653
2654 BT_DBG("unacked_frames %u", chan->unacked_frames);
2655}
2656
2657static void l2cap_abort_rx_srej_sent(struct l2cap_chan *chan)
2658{
2659 BT_DBG("chan %p", chan);
2660
2661 chan->expected_tx_seq = chan->buffer_seq;
2662 l2cap_seq_list_clear(&chan->srej_list);
2663 skb_queue_purge(&chan->srej_q);
2664 chan->rx_state = L2CAP_RX_STATE_RECV;
2665}
2666
2667static void l2cap_tx_state_xmit(struct l2cap_chan *chan,
2668 struct l2cap_ctrl *control,
2669 struct sk_buff_head *skbs, u8 event)
2670{
2671 BT_DBG("chan %p, control %p, skbs %p, event %d", chan, control, skbs,
2672 event);
2673
2674 switch (event) {
2675 case L2CAP_EV_DATA_REQUEST:
2676 if (chan->tx_send_head == NULL)
2677 chan->tx_send_head = skb_peek(skbs);
2678
2679 skb_queue_splice_tail_init(skbs, &chan->tx_q);
2680 l2cap_ertm_send(chan);
2681 break;
2682 case L2CAP_EV_LOCAL_BUSY_DETECTED:
2683 BT_DBG("Enter LOCAL_BUSY");
2684 set_bit(CONN_LOCAL_BUSY, &chan->conn_state);
2685
2686 if (chan->rx_state == L2CAP_RX_STATE_SREJ_SENT) {
2687 /* The SREJ_SENT state must be aborted if we are to
2688 * enter the LOCAL_BUSY state.
2689 */
2690 l2cap_abort_rx_srej_sent(chan);
2691 }
2692
2693 l2cap_send_ack(chan);
2694
2695 break;
2696 case L2CAP_EV_LOCAL_BUSY_CLEAR:
2697 BT_DBG("Exit LOCAL_BUSY");
2698 clear_bit(CONN_LOCAL_BUSY, &chan->conn_state);
2699
2700 if (test_bit(CONN_RNR_SENT, &chan->conn_state)) {
2701 struct l2cap_ctrl local_control;
2702
2703 memset(&local_control, 0, sizeof(local_control));
2704 local_control.sframe = 1;
2705 local_control.super = L2CAP_SUPER_RR;
2706 local_control.poll = 1;
2707 local_control.reqseq = chan->buffer_seq;
2708 l2cap_send_sframe(chan, &local_control);
2709
2710 chan->retry_count = 1;
2711 __set_monitor_timer(chan);
2712 chan->tx_state = L2CAP_TX_STATE_WAIT_F;
2713 }
2714 break;
2715 case L2CAP_EV_RECV_REQSEQ_AND_FBIT:
2716 l2cap_process_reqseq(chan, control->reqseq);
2717 break;
2718 case L2CAP_EV_EXPLICIT_POLL:
2719 l2cap_send_rr_or_rnr(chan, 1);
2720 chan->retry_count = 1;
2721 __set_monitor_timer(chan);
2722 __clear_ack_timer(chan);
2723 chan->tx_state = L2CAP_TX_STATE_WAIT_F;
2724 break;
2725 case L2CAP_EV_RETRANS_TO:
2726 l2cap_send_rr_or_rnr(chan, 1);
2727 chan->retry_count = 1;
2728 __set_monitor_timer(chan);
2729 chan->tx_state = L2CAP_TX_STATE_WAIT_F;
2730 break;
2731 case L2CAP_EV_RECV_FBIT:
2732 /* Nothing to process */
2733 break;
2734 default:
2735 break;
2736 }
2737}
2738
2739static void l2cap_tx_state_wait_f(struct l2cap_chan *chan,
2740 struct l2cap_ctrl *control,
2741 struct sk_buff_head *skbs, u8 event)
2742{
2743 BT_DBG("chan %p, control %p, skbs %p, event %d", chan, control, skbs,
2744 event);
2745
2746 switch (event) {
2747 case L2CAP_EV_DATA_REQUEST:
2748 if (chan->tx_send_head == NULL)
2749 chan->tx_send_head = skb_peek(skbs);
2750 /* Queue data, but don't send. */
2751 skb_queue_splice_tail_init(skbs, &chan->tx_q);
2752 break;
2753 case L2CAP_EV_LOCAL_BUSY_DETECTED:
2754 BT_DBG("Enter LOCAL_BUSY");
2755 set_bit(CONN_LOCAL_BUSY, &chan->conn_state);
2756
2757 if (chan->rx_state == L2CAP_RX_STATE_SREJ_SENT) {
2758 /* The SREJ_SENT state must be aborted if we are to
2759 * enter the LOCAL_BUSY state.
2760 */
2761 l2cap_abort_rx_srej_sent(chan);
2762 }
2763
2764 l2cap_send_ack(chan);
2765
2766 break;
2767 case L2CAP_EV_LOCAL_BUSY_CLEAR:
2768 BT_DBG("Exit LOCAL_BUSY");
2769 clear_bit(CONN_LOCAL_BUSY, &chan->conn_state);
2770
2771 if (test_bit(CONN_RNR_SENT, &chan->conn_state)) {
2772 struct l2cap_ctrl local_control;
2773 memset(&local_control, 0, sizeof(local_control));
2774 local_control.sframe = 1;
2775 local_control.super = L2CAP_SUPER_RR;
2776 local_control.poll = 1;
2777 local_control.reqseq = chan->buffer_seq;
2778 l2cap_send_sframe(chan, &local_control);
2779
2780 chan->retry_count = 1;
2781 __set_monitor_timer(chan);
2782 chan->tx_state = L2CAP_TX_STATE_WAIT_F;
2783 }
2784 break;
2785 case L2CAP_EV_RECV_REQSEQ_AND_FBIT:
2786 l2cap_process_reqseq(chan, control->reqseq);
2787
2788 /* Fall through */
2789
2790 case L2CAP_EV_RECV_FBIT:
2791 if (control && control->final) {
2792 __clear_monitor_timer(chan);
2793 if (chan->unacked_frames > 0)
2794 __set_retrans_timer(chan);
2795 chan->retry_count = 0;
2796 chan->tx_state = L2CAP_TX_STATE_XMIT;
2797 BT_DBG("recv fbit tx_state 0x2.2%x", chan->tx_state);
2798 }
2799 break;
2800 case L2CAP_EV_EXPLICIT_POLL:
2801 /* Ignore */
2802 break;
2803 case L2CAP_EV_MONITOR_TO:
2804 if (chan->max_tx == 0 || chan->retry_count < chan->max_tx) {
2805 l2cap_send_rr_or_rnr(chan, 1);
2806 __set_monitor_timer(chan);
2807 chan->retry_count++;
2808 } else {
2809 l2cap_send_disconn_req(chan, ECONNABORTED);
2810 }
2811 break;
2812 default:
2813 break;
2814 }
2815}
2816
2817static void l2cap_tx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
2818 struct sk_buff_head *skbs, u8 event)
2819{
2820 BT_DBG("chan %p, control %p, skbs %p, event %d, state %d",
2821 chan, control, skbs, event, chan->tx_state);
2822
2823 switch (chan->tx_state) {
2824 case L2CAP_TX_STATE_XMIT:
2825 l2cap_tx_state_xmit(chan, control, skbs, event);
2826 break;
2827 case L2CAP_TX_STATE_WAIT_F:
2828 l2cap_tx_state_wait_f(chan, control, skbs, event);
2829 break;
2830 default:
2831 /* Ignore event */
2832 break;
2833 }
2834}
2835
2836static void l2cap_pass_to_tx(struct l2cap_chan *chan,
2837 struct l2cap_ctrl *control)
2838{
2839 BT_DBG("chan %p, control %p", chan, control);
2840 l2cap_tx(chan, control, NULL, L2CAP_EV_RECV_REQSEQ_AND_FBIT);
2841}
2842
2843static void l2cap_pass_to_tx_fbit(struct l2cap_chan *chan,
2844 struct l2cap_ctrl *control)
2845{
2846 BT_DBG("chan %p, control %p", chan, control);
2847 l2cap_tx(chan, control, NULL, L2CAP_EV_RECV_FBIT);
2848}
2849
2850/* Copy frame to all raw sockets on that connection */
2851static void l2cap_raw_recv(struct l2cap_conn *conn, struct sk_buff *skb)
2852{
2853 struct sk_buff *nskb;
2854 struct l2cap_chan *chan;
2855
2856 BT_DBG("conn %p", conn);
2857
2858 mutex_lock(&conn->chan_lock);
2859
2860 list_for_each_entry(chan, &conn->chan_l, list) {
2861 if (chan->chan_type != L2CAP_CHAN_RAW)
2862 continue;
2863
2864 /* Don't send frame to the channel it came from */
2865 if (bt_cb(skb)->l2cap.chan == chan)
2866 continue;
2867
2868 nskb = skb_clone(skb, GFP_KERNEL);
2869 if (!nskb)
2870 continue;
2871 if (chan->ops->recv(chan, nskb))
2872 kfree_skb(nskb);
2873 }
2874
2875 mutex_unlock(&conn->chan_lock);
2876}
2877
2878/* ---- L2CAP signalling commands ---- */
2879static struct sk_buff *l2cap_build_cmd(struct l2cap_conn *conn, u8 code,
2880 u8 ident, u16 dlen, void *data)
2881{
2882 struct sk_buff *skb, **frag;
2883 struct l2cap_cmd_hdr *cmd;
2884 struct l2cap_hdr *lh;
2885 int len, count;
2886
2887 BT_DBG("conn %p, code 0x%2.2x, ident 0x%2.2x, len %u",
2888 conn, code, ident, dlen);
2889
2890 if (conn->mtu < L2CAP_HDR_SIZE + L2CAP_CMD_HDR_SIZE)
2891 return NULL;
2892
2893 len = L2CAP_HDR_SIZE + L2CAP_CMD_HDR_SIZE + dlen;
2894 count = min_t(unsigned int, conn->mtu, len);
2895
2896 skb = bt_skb_alloc(count, GFP_KERNEL);
2897 if (!skb)
2898 return NULL;
2899
2900 lh = (struct l2cap_hdr *) skb_put(skb, L2CAP_HDR_SIZE);
2901 lh->len = cpu_to_le16(L2CAP_CMD_HDR_SIZE + dlen);
2902
2903 if (conn->hcon->type == LE_LINK)
2904 lh->cid = cpu_to_le16(L2CAP_CID_LE_SIGNALING);
2905 else
2906 lh->cid = cpu_to_le16(L2CAP_CID_SIGNALING);
2907
2908 cmd = (struct l2cap_cmd_hdr *) skb_put(skb, L2CAP_CMD_HDR_SIZE);
2909 cmd->code = code;
2910 cmd->ident = ident;
2911 cmd->len = cpu_to_le16(dlen);
2912
2913 if (dlen) {
2914 count -= L2CAP_HDR_SIZE + L2CAP_CMD_HDR_SIZE;
2915 memcpy(skb_put(skb, count), data, count);
2916 data += count;
2917 }
2918
2919 len -= skb->len;
2920
2921 /* Continuation fragments (no L2CAP header) */
2922 frag = &skb_shinfo(skb)->frag_list;
2923 while (len) {
2924 count = min_t(unsigned int, conn->mtu, len);
2925
2926 *frag = bt_skb_alloc(count, GFP_KERNEL);
2927 if (!*frag)
2928 goto fail;
2929
2930 memcpy(skb_put(*frag, count), data, count);
2931
2932 len -= count;
2933 data += count;
2934
2935 frag = &(*frag)->next;
2936 }
2937
2938 return skb;
2939
2940fail:
2941 kfree_skb(skb);
2942 return NULL;
2943}
2944
2945static inline int l2cap_get_conf_opt(void **ptr, int *type, int *olen,
2946 unsigned long *val)
2947{
2948 struct l2cap_conf_opt *opt = *ptr;
2949 int len;
2950
2951 len = L2CAP_CONF_OPT_SIZE + opt->len;
2952 *ptr += len;
2953
2954 *type = opt->type;
2955 *olen = opt->len;
2956
2957 switch (opt->len) {
2958 case 1:
2959 *val = *((u8 *) opt->val);
2960 break;
2961
2962 case 2:
2963 *val = get_unaligned_le16(opt->val);
2964 break;
2965
2966 case 4:
2967 *val = get_unaligned_le32(opt->val);
2968 break;
2969
2970 default:
2971 *val = (unsigned long) opt->val;
2972 break;
2973 }
2974
2975 BT_DBG("type 0x%2.2x len %u val 0x%lx", *type, opt->len, *val);
2976 return len;
2977}
2978
2979static void l2cap_add_conf_opt(void **ptr, u8 type, u8 len, unsigned long val)
2980{
2981 struct l2cap_conf_opt *opt = *ptr;
2982
2983 BT_DBG("type 0x%2.2x len %u val 0x%lx", type, len, val);
2984
2985 opt->type = type;
2986 opt->len = len;
2987
2988 switch (len) {
2989 case 1:
2990 *((u8 *) opt->val) = val;
2991 break;
2992
2993 case 2:
2994 put_unaligned_le16(val, opt->val);
2995 break;
2996
2997 case 4:
2998 put_unaligned_le32(val, opt->val);
2999 break;
3000
3001 default:
3002 memcpy(opt->val, (void *) val, len);
3003 break;
3004 }
3005
3006 *ptr += L2CAP_CONF_OPT_SIZE + len;
3007}
3008
3009static void l2cap_add_opt_efs(void **ptr, struct l2cap_chan *chan)
3010{
3011 struct l2cap_conf_efs efs;
3012
3013 switch (chan->mode) {
3014 case L2CAP_MODE_ERTM:
3015 efs.id = chan->local_id;
3016 efs.stype = chan->local_stype;
3017 efs.msdu = cpu_to_le16(chan->local_msdu);
3018 efs.sdu_itime = cpu_to_le32(chan->local_sdu_itime);
3019 efs.acc_lat = cpu_to_le32(L2CAP_DEFAULT_ACC_LAT);
3020 efs.flush_to = cpu_to_le32(L2CAP_EFS_DEFAULT_FLUSH_TO);
3021 break;
3022
3023 case L2CAP_MODE_STREAMING:
3024 efs.id = 1;
3025 efs.stype = L2CAP_SERV_BESTEFFORT;
3026 efs.msdu = cpu_to_le16(chan->local_msdu);
3027 efs.sdu_itime = cpu_to_le32(chan->local_sdu_itime);
3028 efs.acc_lat = 0;
3029 efs.flush_to = 0;
3030 break;
3031
3032 default:
3033 return;
3034 }
3035
3036 l2cap_add_conf_opt(ptr, L2CAP_CONF_EFS, sizeof(efs),
3037 (unsigned long) &efs);
3038}
3039
3040static void l2cap_ack_timeout(struct work_struct *work)
3041{
3042 struct l2cap_chan *chan = container_of(work, struct l2cap_chan,
3043 ack_timer.work);
3044 u16 frames_to_ack;
3045
3046 BT_DBG("chan %p", chan);
3047
3048 l2cap_chan_lock(chan);
3049
3050 frames_to_ack = __seq_offset(chan, chan->buffer_seq,
3051 chan->last_acked_seq);
3052
3053 if (frames_to_ack)
3054 l2cap_send_rr_or_rnr(chan, 0);
3055
3056 l2cap_chan_unlock(chan);
3057 l2cap_chan_put(chan);
3058}
3059
3060int l2cap_ertm_init(struct l2cap_chan *chan)
3061{
3062 int err;
3063
3064 chan->next_tx_seq = 0;
3065 chan->expected_tx_seq = 0;
3066 chan->expected_ack_seq = 0;
3067 chan->unacked_frames = 0;
3068 chan->buffer_seq = 0;
3069 chan->frames_sent = 0;
3070 chan->last_acked_seq = 0;
3071 chan->sdu = NULL;
3072 chan->sdu_last_frag = NULL;
3073 chan->sdu_len = 0;
3074
3075 skb_queue_head_init(&chan->tx_q);
3076
3077 chan->local_amp_id = AMP_ID_BREDR;
3078 chan->move_id = AMP_ID_BREDR;
3079 chan->move_state = L2CAP_MOVE_STABLE;
3080 chan->move_role = L2CAP_MOVE_ROLE_NONE;
3081
3082 if (chan->mode != L2CAP_MODE_ERTM)
3083 return 0;
3084
3085 chan->rx_state = L2CAP_RX_STATE_RECV;
3086 chan->tx_state = L2CAP_TX_STATE_XMIT;
3087
3088 INIT_DELAYED_WORK(&chan->retrans_timer, l2cap_retrans_timeout);
3089 INIT_DELAYED_WORK(&chan->monitor_timer, l2cap_monitor_timeout);
3090 INIT_DELAYED_WORK(&chan->ack_timer, l2cap_ack_timeout);
3091
3092 skb_queue_head_init(&chan->srej_q);
3093
3094 err = l2cap_seq_list_init(&chan->srej_list, chan->tx_win);
3095 if (err < 0)
3096 return err;
3097
3098 err = l2cap_seq_list_init(&chan->retrans_list, chan->remote_tx_win);
3099 if (err < 0)
3100 l2cap_seq_list_free(&chan->srej_list);
3101
3102 return err;
3103}
3104
3105static inline __u8 l2cap_select_mode(__u8 mode, __u16 remote_feat_mask)
3106{
3107 switch (mode) {
3108 case L2CAP_MODE_STREAMING:
3109 case L2CAP_MODE_ERTM:
3110 if (l2cap_mode_supported(mode, remote_feat_mask))
3111 return mode;
3112 /* fall through */
3113 default:
3114 return L2CAP_MODE_BASIC;
3115 }
3116}
3117
3118static inline bool __l2cap_ews_supported(struct l2cap_conn *conn)
3119{
3120 return ((conn->local_fixed_chan & L2CAP_FC_A2MP) &&
3121 (conn->feat_mask & L2CAP_FEAT_EXT_WINDOW));
3122}
3123
3124static inline bool __l2cap_efs_supported(struct l2cap_conn *conn)
3125{
3126 return ((conn->local_fixed_chan & L2CAP_FC_A2MP) &&
3127 (conn->feat_mask & L2CAP_FEAT_EXT_FLOW));
3128}
3129
3130static void __l2cap_set_ertm_timeouts(struct l2cap_chan *chan,
3131 struct l2cap_conf_rfc *rfc)
3132{
3133 if (chan->local_amp_id != AMP_ID_BREDR && chan->hs_hcon) {
3134 u64 ertm_to = chan->hs_hcon->hdev->amp_be_flush_to;
3135
3136 /* Class 1 devices have must have ERTM timeouts
3137 * exceeding the Link Supervision Timeout. The
3138 * default Link Supervision Timeout for AMP
3139 * controllers is 10 seconds.
3140 *
3141 * Class 1 devices use 0xffffffff for their
3142 * best-effort flush timeout, so the clamping logic
3143 * will result in a timeout that meets the above
3144 * requirement. ERTM timeouts are 16-bit values, so
3145 * the maximum timeout is 65.535 seconds.
3146 */
3147
3148 /* Convert timeout to milliseconds and round */
3149 ertm_to = DIV_ROUND_UP_ULL(ertm_to, 1000);
3150
3151 /* This is the recommended formula for class 2 devices
3152 * that start ERTM timers when packets are sent to the
3153 * controller.
3154 */
3155 ertm_to = 3 * ertm_to + 500;
3156
3157 if (ertm_to > 0xffff)
3158 ertm_to = 0xffff;
3159
3160 rfc->retrans_timeout = cpu_to_le16((u16) ertm_to);
3161 rfc->monitor_timeout = rfc->retrans_timeout;
3162 } else {
3163 rfc->retrans_timeout = cpu_to_le16(L2CAP_DEFAULT_RETRANS_TO);
3164 rfc->monitor_timeout = cpu_to_le16(L2CAP_DEFAULT_MONITOR_TO);
3165 }
3166}
3167
3168static inline void l2cap_txwin_setup(struct l2cap_chan *chan)
3169{
3170 if (chan->tx_win > L2CAP_DEFAULT_TX_WINDOW &&
3171 __l2cap_ews_supported(chan->conn)) {
3172 /* use extended control field */
3173 set_bit(FLAG_EXT_CTRL, &chan->flags);
3174 chan->tx_win_max = L2CAP_DEFAULT_EXT_WINDOW;
3175 } else {
3176 chan->tx_win = min_t(u16, chan->tx_win,
3177 L2CAP_DEFAULT_TX_WINDOW);
3178 chan->tx_win_max = L2CAP_DEFAULT_TX_WINDOW;
3179 }
3180 chan->ack_win = chan->tx_win;
3181}
3182
3183static int l2cap_build_conf_req(struct l2cap_chan *chan, void *data)
3184{
3185 struct l2cap_conf_req *req = data;
3186 struct l2cap_conf_rfc rfc = { .mode = chan->mode };
3187 void *ptr = req->data;
3188 u16 size;
3189
3190 BT_DBG("chan %p", chan);
3191
3192 if (chan->num_conf_req || chan->num_conf_rsp)
3193 goto done;
3194
3195 switch (chan->mode) {
3196 case L2CAP_MODE_STREAMING:
3197 case L2CAP_MODE_ERTM:
3198 if (test_bit(CONF_STATE2_DEVICE, &chan->conf_state))
3199 break;
3200
3201 if (__l2cap_efs_supported(chan->conn))
3202 set_bit(FLAG_EFS_ENABLE, &chan->flags);
3203
3204 /* fall through */
3205 default:
3206 chan->mode = l2cap_select_mode(rfc.mode, chan->conn->feat_mask);
3207 break;
3208 }
3209
3210done:
3211 if (chan->imtu != L2CAP_DEFAULT_MTU)
3212 l2cap_add_conf_opt(&ptr, L2CAP_CONF_MTU, 2, chan->imtu);
3213
3214 switch (chan->mode) {
3215 case L2CAP_MODE_BASIC:
3216 if (disable_ertm)
3217 break;
3218
3219 if (!(chan->conn->feat_mask & L2CAP_FEAT_ERTM) &&
3220 !(chan->conn->feat_mask & L2CAP_FEAT_STREAMING))
3221 break;
3222
3223 rfc.mode = L2CAP_MODE_BASIC;
3224 rfc.txwin_size = 0;
3225 rfc.max_transmit = 0;
3226 rfc.retrans_timeout = 0;
3227 rfc.monitor_timeout = 0;
3228 rfc.max_pdu_size = 0;
3229
3230 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3231 (unsigned long) &rfc);
3232 break;
3233
3234 case L2CAP_MODE_ERTM:
3235 rfc.mode = L2CAP_MODE_ERTM;
3236 rfc.max_transmit = chan->max_tx;
3237
3238 __l2cap_set_ertm_timeouts(chan, &rfc);
3239
3240 size = min_t(u16, L2CAP_DEFAULT_MAX_PDU_SIZE, chan->conn->mtu -
3241 L2CAP_EXT_HDR_SIZE - L2CAP_SDULEN_SIZE -
3242 L2CAP_FCS_SIZE);
3243 rfc.max_pdu_size = cpu_to_le16(size);
3244
3245 l2cap_txwin_setup(chan);
3246
3247 rfc.txwin_size = min_t(u16, chan->tx_win,
3248 L2CAP_DEFAULT_TX_WINDOW);
3249
3250 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3251 (unsigned long) &rfc);
3252
3253 if (test_bit(FLAG_EFS_ENABLE, &chan->flags))
3254 l2cap_add_opt_efs(&ptr, chan);
3255
3256 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
3257 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EWS, 2,
3258 chan->tx_win);
3259
3260 if (chan->conn->feat_mask & L2CAP_FEAT_FCS)
3261 if (chan->fcs == L2CAP_FCS_NONE ||
3262 test_bit(CONF_RECV_NO_FCS, &chan->conf_state)) {
3263 chan->fcs = L2CAP_FCS_NONE;
3264 l2cap_add_conf_opt(&ptr, L2CAP_CONF_FCS, 1,
3265 chan->fcs);
3266 }
3267 break;
3268
3269 case L2CAP_MODE_STREAMING:
3270 l2cap_txwin_setup(chan);
3271 rfc.mode = L2CAP_MODE_STREAMING;
3272 rfc.txwin_size = 0;
3273 rfc.max_transmit = 0;
3274 rfc.retrans_timeout = 0;
3275 rfc.monitor_timeout = 0;
3276
3277 size = min_t(u16, L2CAP_DEFAULT_MAX_PDU_SIZE, chan->conn->mtu -
3278 L2CAP_EXT_HDR_SIZE - L2CAP_SDULEN_SIZE -
3279 L2CAP_FCS_SIZE);
3280 rfc.max_pdu_size = cpu_to_le16(size);
3281
3282 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3283 (unsigned long) &rfc);
3284
3285 if (test_bit(FLAG_EFS_ENABLE, &chan->flags))
3286 l2cap_add_opt_efs(&ptr, chan);
3287
3288 if (chan->conn->feat_mask & L2CAP_FEAT_FCS)
3289 if (chan->fcs == L2CAP_FCS_NONE ||
3290 test_bit(CONF_RECV_NO_FCS, &chan->conf_state)) {
3291 chan->fcs = L2CAP_FCS_NONE;
3292 l2cap_add_conf_opt(&ptr, L2CAP_CONF_FCS, 1,
3293 chan->fcs);
3294 }
3295 break;
3296 }
3297
3298 req->dcid = cpu_to_le16(chan->dcid);
3299 req->flags = cpu_to_le16(0);
3300
3301 return ptr - data;
3302}
3303
3304static int l2cap_parse_conf_req(struct l2cap_chan *chan, void *data)
3305{
3306 struct l2cap_conf_rsp *rsp = data;
3307 void *ptr = rsp->data;
3308 void *req = chan->conf_req;
3309 int len = chan->conf_len;
3310 int type, hint, olen;
3311 unsigned long val;
3312 struct l2cap_conf_rfc rfc = { .mode = L2CAP_MODE_BASIC };
3313 struct l2cap_conf_efs efs;
3314 u8 remote_efs = 0;
3315 u16 mtu = L2CAP_DEFAULT_MTU;
3316 u16 result = L2CAP_CONF_SUCCESS;
3317 u16 size;
3318
3319 BT_DBG("chan %p", chan);
3320
3321 while (len >= L2CAP_CONF_OPT_SIZE) {
3322 len -= l2cap_get_conf_opt(&req, &type, &olen, &val);
3323
3324 hint = type & L2CAP_CONF_HINT;
3325 type &= L2CAP_CONF_MASK;
3326
3327 switch (type) {
3328 case L2CAP_CONF_MTU:
3329 mtu = val;
3330 break;
3331
3332 case L2CAP_CONF_FLUSH_TO:
3333 chan->flush_to = val;
3334 break;
3335
3336 case L2CAP_CONF_QOS:
3337 break;
3338
3339 case L2CAP_CONF_RFC:
3340 if (olen == sizeof(rfc))
3341 memcpy(&rfc, (void *) val, olen);
3342 break;
3343
3344 case L2CAP_CONF_FCS:
3345 if (val == L2CAP_FCS_NONE)
3346 set_bit(CONF_RECV_NO_FCS, &chan->conf_state);
3347 break;
3348
3349 case L2CAP_CONF_EFS:
3350 remote_efs = 1;
3351 if (olen == sizeof(efs))
3352 memcpy(&efs, (void *) val, olen);
3353 break;
3354
3355 case L2CAP_CONF_EWS:
3356 if (!(chan->conn->local_fixed_chan & L2CAP_FC_A2MP))
3357 return -ECONNREFUSED;
3358
3359 set_bit(FLAG_EXT_CTRL, &chan->flags);
3360 set_bit(CONF_EWS_RECV, &chan->conf_state);
3361 chan->tx_win_max = L2CAP_DEFAULT_EXT_WINDOW;
3362 chan->remote_tx_win = val;
3363 break;
3364
3365 default:
3366 if (hint)
3367 break;
3368
3369 result = L2CAP_CONF_UNKNOWN;
3370 *((u8 *) ptr++) = type;
3371 break;
3372 }
3373 }
3374
3375 if (chan->num_conf_rsp || chan->num_conf_req > 1)
3376 goto done;
3377
3378 switch (chan->mode) {
3379 case L2CAP_MODE_STREAMING:
3380 case L2CAP_MODE_ERTM:
3381 if (!test_bit(CONF_STATE2_DEVICE, &chan->conf_state)) {
3382 chan->mode = l2cap_select_mode(rfc.mode,
3383 chan->conn->feat_mask);
3384 break;
3385 }
3386
3387 if (remote_efs) {
3388 if (__l2cap_efs_supported(chan->conn))
3389 set_bit(FLAG_EFS_ENABLE, &chan->flags);
3390 else
3391 return -ECONNREFUSED;
3392 }
3393
3394 if (chan->mode != rfc.mode)
3395 return -ECONNREFUSED;
3396
3397 break;
3398 }
3399
3400done:
3401 if (chan->mode != rfc.mode) {
3402 result = L2CAP_CONF_UNACCEPT;
3403 rfc.mode = chan->mode;
3404
3405 if (chan->num_conf_rsp == 1)
3406 return -ECONNREFUSED;
3407
3408 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3409 (unsigned long) &rfc);
3410 }
3411
3412 if (result == L2CAP_CONF_SUCCESS) {
3413 /* Configure output options and let the other side know
3414 * which ones we don't like. */
3415
3416 if (mtu < L2CAP_DEFAULT_MIN_MTU)
3417 result = L2CAP_CONF_UNACCEPT;
3418 else {
3419 chan->omtu = mtu;
3420 set_bit(CONF_MTU_DONE, &chan->conf_state);
3421 }
3422 l2cap_add_conf_opt(&ptr, L2CAP_CONF_MTU, 2, chan->omtu);
3423
3424 if (remote_efs) {
3425 if (chan->local_stype != L2CAP_SERV_NOTRAFIC &&
3426 efs.stype != L2CAP_SERV_NOTRAFIC &&
3427 efs.stype != chan->local_stype) {
3428
3429 result = L2CAP_CONF_UNACCEPT;
3430
3431 if (chan->num_conf_req >= 1)
3432 return -ECONNREFUSED;
3433
3434 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EFS,
3435 sizeof(efs),
3436 (unsigned long) &efs);
3437 } else {
3438 /* Send PENDING Conf Rsp */
3439 result = L2CAP_CONF_PENDING;
3440 set_bit(CONF_LOC_CONF_PEND, &chan->conf_state);
3441 }
3442 }
3443
3444 switch (rfc.mode) {
3445 case L2CAP_MODE_BASIC:
3446 chan->fcs = L2CAP_FCS_NONE;
3447 set_bit(CONF_MODE_DONE, &chan->conf_state);
3448 break;
3449
3450 case L2CAP_MODE_ERTM:
3451 if (!test_bit(CONF_EWS_RECV, &chan->conf_state))
3452 chan->remote_tx_win = rfc.txwin_size;
3453 else
3454 rfc.txwin_size = L2CAP_DEFAULT_TX_WINDOW;
3455
3456 chan->remote_max_tx = rfc.max_transmit;
3457
3458 size = min_t(u16, le16_to_cpu(rfc.max_pdu_size),
3459 chan->conn->mtu - L2CAP_EXT_HDR_SIZE -
3460 L2CAP_SDULEN_SIZE - L2CAP_FCS_SIZE);
3461 rfc.max_pdu_size = cpu_to_le16(size);
3462 chan->remote_mps = size;
3463
3464 __l2cap_set_ertm_timeouts(chan, &rfc);
3465
3466 set_bit(CONF_MODE_DONE, &chan->conf_state);
3467
3468 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC,
3469 sizeof(rfc), (unsigned long) &rfc);
3470
3471 if (test_bit(FLAG_EFS_ENABLE, &chan->flags)) {
3472 chan->remote_id = efs.id;
3473 chan->remote_stype = efs.stype;
3474 chan->remote_msdu = le16_to_cpu(efs.msdu);
3475 chan->remote_flush_to =
3476 le32_to_cpu(efs.flush_to);
3477 chan->remote_acc_lat =
3478 le32_to_cpu(efs.acc_lat);
3479 chan->remote_sdu_itime =
3480 le32_to_cpu(efs.sdu_itime);
3481 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EFS,
3482 sizeof(efs),
3483 (unsigned long) &efs);
3484 }
3485 break;
3486
3487 case L2CAP_MODE_STREAMING:
3488 size = min_t(u16, le16_to_cpu(rfc.max_pdu_size),
3489 chan->conn->mtu - L2CAP_EXT_HDR_SIZE -
3490 L2CAP_SDULEN_SIZE - L2CAP_FCS_SIZE);
3491 rfc.max_pdu_size = cpu_to_le16(size);
3492 chan->remote_mps = size;
3493
3494 set_bit(CONF_MODE_DONE, &chan->conf_state);
3495
3496 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3497 (unsigned long) &rfc);
3498
3499 break;
3500
3501 default:
3502 result = L2CAP_CONF_UNACCEPT;
3503
3504 memset(&rfc, 0, sizeof(rfc));
3505 rfc.mode = chan->mode;
3506 }
3507
3508 if (result == L2CAP_CONF_SUCCESS)
3509 set_bit(CONF_OUTPUT_DONE, &chan->conf_state);
3510 }
3511 rsp->scid = cpu_to_le16(chan->dcid);
3512 rsp->result = cpu_to_le16(result);
3513 rsp->flags = cpu_to_le16(0);
3514
3515 return ptr - data;
3516}
3517
3518static int l2cap_parse_conf_rsp(struct l2cap_chan *chan, void *rsp, int len,
3519 void *data, u16 *result)
3520{
3521 struct l2cap_conf_req *req = data;
3522 void *ptr = req->data;
3523 int type, olen;
3524 unsigned long val;
3525 struct l2cap_conf_rfc rfc = { .mode = L2CAP_MODE_BASIC };
3526 struct l2cap_conf_efs efs;
3527
3528 BT_DBG("chan %p, rsp %p, len %d, req %p", chan, rsp, len, data);
3529
3530 while (len >= L2CAP_CONF_OPT_SIZE) {
3531 len -= l2cap_get_conf_opt(&rsp, &type, &olen, &val);
3532
3533 switch (type) {
3534 case L2CAP_CONF_MTU:
3535 if (val < L2CAP_DEFAULT_MIN_MTU) {
3536 *result = L2CAP_CONF_UNACCEPT;
3537 chan->imtu = L2CAP_DEFAULT_MIN_MTU;
3538 } else
3539 chan->imtu = val;
3540 l2cap_add_conf_opt(&ptr, L2CAP_CONF_MTU, 2, chan->imtu);
3541 break;
3542
3543 case L2CAP_CONF_FLUSH_TO:
3544 chan->flush_to = val;
3545 l2cap_add_conf_opt(&ptr, L2CAP_CONF_FLUSH_TO,
3546 2, chan->flush_to);
3547 break;
3548
3549 case L2CAP_CONF_RFC:
3550 if (olen == sizeof(rfc))
3551 memcpy(&rfc, (void *)val, olen);
3552
3553 if (test_bit(CONF_STATE2_DEVICE, &chan->conf_state) &&
3554 rfc.mode != chan->mode)
3555 return -ECONNREFUSED;
3556
3557 chan->fcs = 0;
3558
3559 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC,
3560 sizeof(rfc), (unsigned long) &rfc);
3561 break;
3562
3563 case L2CAP_CONF_EWS:
3564 chan->ack_win = min_t(u16, val, chan->ack_win);
3565 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EWS, 2,
3566 chan->tx_win);
3567 break;
3568
3569 case L2CAP_CONF_EFS:
3570 if (olen == sizeof(efs))
3571 memcpy(&efs, (void *)val, olen);
3572
3573 if (chan->local_stype != L2CAP_SERV_NOTRAFIC &&
3574 efs.stype != L2CAP_SERV_NOTRAFIC &&
3575 efs.stype != chan->local_stype)
3576 return -ECONNREFUSED;
3577
3578 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EFS, sizeof(efs),
3579 (unsigned long) &efs);
3580 break;
3581
3582 case L2CAP_CONF_FCS:
3583 if (*result == L2CAP_CONF_PENDING)
3584 if (val == L2CAP_FCS_NONE)
3585 set_bit(CONF_RECV_NO_FCS,
3586 &chan->conf_state);
3587 break;
3588 }
3589 }
3590
3591 if (chan->mode == L2CAP_MODE_BASIC && chan->mode != rfc.mode)
3592 return -ECONNREFUSED;
3593
3594 chan->mode = rfc.mode;
3595
3596 if (*result == L2CAP_CONF_SUCCESS || *result == L2CAP_CONF_PENDING) {
3597 switch (rfc.mode) {
3598 case L2CAP_MODE_ERTM:
3599 chan->retrans_timeout = le16_to_cpu(rfc.retrans_timeout);
3600 chan->monitor_timeout = le16_to_cpu(rfc.monitor_timeout);
3601 chan->mps = le16_to_cpu(rfc.max_pdu_size);
3602 if (!test_bit(FLAG_EXT_CTRL, &chan->flags))
3603 chan->ack_win = min_t(u16, chan->ack_win,
3604 rfc.txwin_size);
3605
3606 if (test_bit(FLAG_EFS_ENABLE, &chan->flags)) {
3607 chan->local_msdu = le16_to_cpu(efs.msdu);
3608 chan->local_sdu_itime =
3609 le32_to_cpu(efs.sdu_itime);
3610 chan->local_acc_lat = le32_to_cpu(efs.acc_lat);
3611 chan->local_flush_to =
3612 le32_to_cpu(efs.flush_to);
3613 }
3614 break;
3615
3616 case L2CAP_MODE_STREAMING:
3617 chan->mps = le16_to_cpu(rfc.max_pdu_size);
3618 }
3619 }
3620
3621 req->dcid = cpu_to_le16(chan->dcid);
3622 req->flags = cpu_to_le16(0);
3623
3624 return ptr - data;
3625}
3626
3627static int l2cap_build_conf_rsp(struct l2cap_chan *chan, void *data,
3628 u16 result, u16 flags)
3629{
3630 struct l2cap_conf_rsp *rsp = data;
3631 void *ptr = rsp->data;
3632
3633 BT_DBG("chan %p", chan);
3634
3635 rsp->scid = cpu_to_le16(chan->dcid);
3636 rsp->result = cpu_to_le16(result);
3637 rsp->flags = cpu_to_le16(flags);
3638
3639 return ptr - data;
3640}
3641
3642void __l2cap_le_connect_rsp_defer(struct l2cap_chan *chan)
3643{
3644 struct l2cap_le_conn_rsp rsp;
3645 struct l2cap_conn *conn = chan->conn;
3646
3647 BT_DBG("chan %p", chan);
3648
3649 rsp.dcid = cpu_to_le16(chan->scid);
3650 rsp.mtu = cpu_to_le16(chan->imtu);
3651 rsp.mps = cpu_to_le16(chan->mps);
3652 rsp.credits = cpu_to_le16(chan->rx_credits);
3653 rsp.result = cpu_to_le16(L2CAP_CR_SUCCESS);
3654
3655 l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CONN_RSP, sizeof(rsp),
3656 &rsp);
3657}
3658
3659void __l2cap_connect_rsp_defer(struct l2cap_chan *chan)
3660{
3661 struct l2cap_conn_rsp rsp;
3662 struct l2cap_conn *conn = chan->conn;
3663 u8 buf[128];
3664 u8 rsp_code;
3665
3666 rsp.scid = cpu_to_le16(chan->dcid);
3667 rsp.dcid = cpu_to_le16(chan->scid);
3668 rsp.result = cpu_to_le16(L2CAP_CR_SUCCESS);
3669 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
3670
3671 if (chan->hs_hcon)
3672 rsp_code = L2CAP_CREATE_CHAN_RSP;
3673 else
3674 rsp_code = L2CAP_CONN_RSP;
3675
3676 BT_DBG("chan %p rsp_code %u", chan, rsp_code);
3677
3678 l2cap_send_cmd(conn, chan->ident, rsp_code, sizeof(rsp), &rsp);
3679
3680 if (test_and_set_bit(CONF_REQ_SENT, &chan->conf_state))
3681 return;
3682
3683 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
3684 l2cap_build_conf_req(chan, buf), buf);
3685 chan->num_conf_req++;
3686}
3687
3688static void l2cap_conf_rfc_get(struct l2cap_chan *chan, void *rsp, int len)
3689{
3690 int type, olen;
3691 unsigned long val;
3692 /* Use sane default values in case a misbehaving remote device
3693 * did not send an RFC or extended window size option.
3694 */
3695 u16 txwin_ext = chan->ack_win;
3696 struct l2cap_conf_rfc rfc = {
3697 .mode = chan->mode,
3698 .retrans_timeout = cpu_to_le16(L2CAP_DEFAULT_RETRANS_TO),
3699 .monitor_timeout = cpu_to_le16(L2CAP_DEFAULT_MONITOR_TO),
3700 .max_pdu_size = cpu_to_le16(chan->imtu),
3701 .txwin_size = min_t(u16, chan->ack_win, L2CAP_DEFAULT_TX_WINDOW),
3702 };
3703
3704 BT_DBG("chan %p, rsp %p, len %d", chan, rsp, len);
3705
3706 if ((chan->mode != L2CAP_MODE_ERTM) && (chan->mode != L2CAP_MODE_STREAMING))
3707 return;
3708
3709 while (len >= L2CAP_CONF_OPT_SIZE) {
3710 len -= l2cap_get_conf_opt(&rsp, &type, &olen, &val);
3711
3712 switch (type) {
3713 case L2CAP_CONF_RFC:
3714 if (olen == sizeof(rfc))
3715 memcpy(&rfc, (void *)val, olen);
3716 break;
3717 case L2CAP_CONF_EWS:
3718 txwin_ext = val;
3719 break;
3720 }
3721 }
3722
3723 switch (rfc.mode) {
3724 case L2CAP_MODE_ERTM:
3725 chan->retrans_timeout = le16_to_cpu(rfc.retrans_timeout);
3726 chan->monitor_timeout = le16_to_cpu(rfc.monitor_timeout);
3727 chan->mps = le16_to_cpu(rfc.max_pdu_size);
3728 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
3729 chan->ack_win = min_t(u16, chan->ack_win, txwin_ext);
3730 else
3731 chan->ack_win = min_t(u16, chan->ack_win,
3732 rfc.txwin_size);
3733 break;
3734 case L2CAP_MODE_STREAMING:
3735 chan->mps = le16_to_cpu(rfc.max_pdu_size);
3736 }
3737}
3738
3739static inline int l2cap_command_rej(struct l2cap_conn *conn,
3740 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
3741 u8 *data)
3742{
3743 struct l2cap_cmd_rej_unk *rej = (struct l2cap_cmd_rej_unk *) data;
3744
3745 if (cmd_len < sizeof(*rej))
3746 return -EPROTO;
3747
3748 if (rej->reason != L2CAP_REJ_NOT_UNDERSTOOD)
3749 return 0;
3750
3751 if ((conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT) &&
3752 cmd->ident == conn->info_ident) {
3753 cancel_delayed_work(&conn->info_timer);
3754
3755 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
3756 conn->info_ident = 0;
3757
3758 l2cap_conn_start(conn);
3759 }
3760
3761 return 0;
3762}
3763
3764static struct l2cap_chan *l2cap_connect(struct l2cap_conn *conn,
3765 struct l2cap_cmd_hdr *cmd,
3766 u8 *data, u8 rsp_code, u8 amp_id)
3767{
3768 struct l2cap_conn_req *req = (struct l2cap_conn_req *) data;
3769 struct l2cap_conn_rsp rsp;
3770 struct l2cap_chan *chan = NULL, *pchan;
3771 int result, status = L2CAP_CS_NO_INFO;
3772
3773 u16 dcid = 0, scid = __le16_to_cpu(req->scid);
3774 __le16 psm = req->psm;
3775
3776 BT_DBG("psm 0x%2.2x scid 0x%4.4x", __le16_to_cpu(psm), scid);
3777
3778 /* Check if we have socket listening on psm */
3779 pchan = l2cap_global_chan_by_psm(BT_LISTEN, psm, &conn->hcon->src,
3780 &conn->hcon->dst, ACL_LINK);
3781 if (!pchan) {
3782 result = L2CAP_CR_BAD_PSM;
3783 goto sendresp;
3784 }
3785
3786 mutex_lock(&conn->chan_lock);
3787 l2cap_chan_lock(pchan);
3788
3789 /* Check if the ACL is secure enough (if not SDP) */
3790 if (psm != cpu_to_le16(L2CAP_PSM_SDP) &&
3791 !hci_conn_check_link_mode(conn->hcon)) {
3792 conn->disc_reason = HCI_ERROR_AUTH_FAILURE;
3793 result = L2CAP_CR_SEC_BLOCK;
3794 goto response;
3795 }
3796
3797 result = L2CAP_CR_NO_MEM;
3798
3799 /* Check if we already have channel with that dcid */
3800 if (__l2cap_get_chan_by_dcid(conn, scid))
3801 goto response;
3802
3803 chan = pchan->ops->new_connection(pchan);
3804 if (!chan)
3805 goto response;
3806
3807 /* For certain devices (ex: HID mouse), support for authentication,
3808 * pairing and bonding is optional. For such devices, inorder to avoid
3809 * the ACL alive for too long after L2CAP disconnection, reset the ACL
3810 * disc_timeout back to HCI_DISCONN_TIMEOUT during L2CAP connect.
3811 */
3812 conn->hcon->disc_timeout = HCI_DISCONN_TIMEOUT;
3813
3814 bacpy(&chan->src, &conn->hcon->src);
3815 bacpy(&chan->dst, &conn->hcon->dst);
3816 chan->src_type = bdaddr_src_type(conn->hcon);
3817 chan->dst_type = bdaddr_dst_type(conn->hcon);
3818 chan->psm = psm;
3819 chan->dcid = scid;
3820 chan->local_amp_id = amp_id;
3821
3822 __l2cap_chan_add(conn, chan);
3823
3824 dcid = chan->scid;
3825
3826 __set_chan_timer(chan, chan->ops->get_sndtimeo(chan));
3827
3828 chan->ident = cmd->ident;
3829
3830 if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE) {
3831 if (l2cap_chan_check_security(chan, false)) {
3832 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) {
3833 l2cap_state_change(chan, BT_CONNECT2);
3834 result = L2CAP_CR_PEND;
3835 status = L2CAP_CS_AUTHOR_PEND;
3836 chan->ops->defer(chan);
3837 } else {
3838 /* Force pending result for AMP controllers.
3839 * The connection will succeed after the
3840 * physical link is up.
3841 */
3842 if (amp_id == AMP_ID_BREDR) {
3843 l2cap_state_change(chan, BT_CONFIG);
3844 result = L2CAP_CR_SUCCESS;
3845 } else {
3846 l2cap_state_change(chan, BT_CONNECT2);
3847 result = L2CAP_CR_PEND;
3848 }
3849 status = L2CAP_CS_NO_INFO;
3850 }
3851 } else {
3852 l2cap_state_change(chan, BT_CONNECT2);
3853 result = L2CAP_CR_PEND;
3854 status = L2CAP_CS_AUTHEN_PEND;
3855 }
3856 } else {
3857 l2cap_state_change(chan, BT_CONNECT2);
3858 result = L2CAP_CR_PEND;
3859 status = L2CAP_CS_NO_INFO;
3860 }
3861
3862response:
3863 l2cap_chan_unlock(pchan);
3864 mutex_unlock(&conn->chan_lock);
3865 l2cap_chan_put(pchan);
3866
3867sendresp:
3868 rsp.scid = cpu_to_le16(scid);
3869 rsp.dcid = cpu_to_le16(dcid);
3870 rsp.result = cpu_to_le16(result);
3871 rsp.status = cpu_to_le16(status);
3872 l2cap_send_cmd(conn, cmd->ident, rsp_code, sizeof(rsp), &rsp);
3873
3874 if (result == L2CAP_CR_PEND && status == L2CAP_CS_NO_INFO) {
3875 struct l2cap_info_req info;
3876 info.type = cpu_to_le16(L2CAP_IT_FEAT_MASK);
3877
3878 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_SENT;
3879 conn->info_ident = l2cap_get_ident(conn);
3880
3881 schedule_delayed_work(&conn->info_timer, L2CAP_INFO_TIMEOUT);
3882
3883 l2cap_send_cmd(conn, conn->info_ident, L2CAP_INFO_REQ,
3884 sizeof(info), &info);
3885 }
3886
3887 if (chan && !test_bit(CONF_REQ_SENT, &chan->conf_state) &&
3888 result == L2CAP_CR_SUCCESS) {
3889 u8 buf[128];
3890 set_bit(CONF_REQ_SENT, &chan->conf_state);
3891 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
3892 l2cap_build_conf_req(chan, buf), buf);
3893 chan->num_conf_req++;
3894 }
3895
3896 return chan;
3897}
3898
3899static int l2cap_connect_req(struct l2cap_conn *conn,
3900 struct l2cap_cmd_hdr *cmd, u16 cmd_len, u8 *data)
3901{
3902 struct hci_dev *hdev = conn->hcon->hdev;
3903 struct hci_conn *hcon = conn->hcon;
3904
3905 if (cmd_len < sizeof(struct l2cap_conn_req))
3906 return -EPROTO;
3907
3908 hci_dev_lock(hdev);
3909 if (hci_dev_test_flag(hdev, HCI_MGMT) &&
3910 !test_and_set_bit(HCI_CONN_MGMT_CONNECTED, &hcon->flags))
3911 mgmt_device_connected(hdev, hcon, 0, NULL, 0);
3912 hci_dev_unlock(hdev);
3913
3914 l2cap_connect(conn, cmd, data, L2CAP_CONN_RSP, 0);
3915 return 0;
3916}
3917
3918static int l2cap_connect_create_rsp(struct l2cap_conn *conn,
3919 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
3920 u8 *data)
3921{
3922 struct l2cap_conn_rsp *rsp = (struct l2cap_conn_rsp *) data;
3923 u16 scid, dcid, result, status;
3924 struct l2cap_chan *chan;
3925 u8 req[128];
3926 int err;
3927
3928 if (cmd_len < sizeof(*rsp))
3929 return -EPROTO;
3930
3931 scid = __le16_to_cpu(rsp->scid);
3932 dcid = __le16_to_cpu(rsp->dcid);
3933 result = __le16_to_cpu(rsp->result);
3934 status = __le16_to_cpu(rsp->status);
3935
3936 BT_DBG("dcid 0x%4.4x scid 0x%4.4x result 0x%2.2x status 0x%2.2x",
3937 dcid, scid, result, status);
3938
3939 mutex_lock(&conn->chan_lock);
3940
3941 if (scid) {
3942 chan = __l2cap_get_chan_by_scid(conn, scid);
3943 if (!chan) {
3944 err = -EBADSLT;
3945 goto unlock;
3946 }
3947 } else {
3948 chan = __l2cap_get_chan_by_ident(conn, cmd->ident);
3949 if (!chan) {
3950 err = -EBADSLT;
3951 goto unlock;
3952 }
3953 }
3954
3955 err = 0;
3956
3957 l2cap_chan_lock(chan);
3958
3959 switch (result) {
3960 case L2CAP_CR_SUCCESS:
3961 l2cap_state_change(chan, BT_CONFIG);
3962 chan->ident = 0;
3963 chan->dcid = dcid;
3964 clear_bit(CONF_CONNECT_PEND, &chan->conf_state);
3965
3966 if (test_and_set_bit(CONF_REQ_SENT, &chan->conf_state))
3967 break;
3968
3969 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
3970 l2cap_build_conf_req(chan, req), req);
3971 chan->num_conf_req++;
3972 break;
3973
3974 case L2CAP_CR_PEND:
3975 set_bit(CONF_CONNECT_PEND, &chan->conf_state);
3976 break;
3977
3978 default:
3979 l2cap_chan_del(chan, ECONNREFUSED);
3980 break;
3981 }
3982
3983 l2cap_chan_unlock(chan);
3984
3985unlock:
3986 mutex_unlock(&conn->chan_lock);
3987
3988 return err;
3989}
3990
3991static inline void set_default_fcs(struct l2cap_chan *chan)
3992{
3993 /* FCS is enabled only in ERTM or streaming mode, if one or both
3994 * sides request it.
3995 */
3996 if (chan->mode != L2CAP_MODE_ERTM && chan->mode != L2CAP_MODE_STREAMING)
3997 chan->fcs = L2CAP_FCS_NONE;
3998 else if (!test_bit(CONF_RECV_NO_FCS, &chan->conf_state))
3999 chan->fcs = L2CAP_FCS_CRC16;
4000}
4001
4002static void l2cap_send_efs_conf_rsp(struct l2cap_chan *chan, void *data,
4003 u8 ident, u16 flags)
4004{
4005 struct l2cap_conn *conn = chan->conn;
4006
4007 BT_DBG("conn %p chan %p ident %d flags 0x%4.4x", conn, chan, ident,
4008 flags);
4009
4010 clear_bit(CONF_LOC_CONF_PEND, &chan->conf_state);
4011 set_bit(CONF_OUTPUT_DONE, &chan->conf_state);
4012
4013 l2cap_send_cmd(conn, ident, L2CAP_CONF_RSP,
4014 l2cap_build_conf_rsp(chan, data,
4015 L2CAP_CONF_SUCCESS, flags), data);
4016}
4017
4018static void cmd_reject_invalid_cid(struct l2cap_conn *conn, u8 ident,
4019 u16 scid, u16 dcid)
4020{
4021 struct l2cap_cmd_rej_cid rej;
4022
4023 rej.reason = cpu_to_le16(L2CAP_REJ_INVALID_CID);
4024 rej.scid = __cpu_to_le16(scid);
4025 rej.dcid = __cpu_to_le16(dcid);
4026
4027 l2cap_send_cmd(conn, ident, L2CAP_COMMAND_REJ, sizeof(rej), &rej);
4028}
4029
4030static inline int l2cap_config_req(struct l2cap_conn *conn,
4031 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4032 u8 *data)
4033{
4034 struct l2cap_conf_req *req = (struct l2cap_conf_req *) data;
4035 u16 dcid, flags;
4036 u8 rsp[64];
4037 struct l2cap_chan *chan;
4038 int len, err = 0;
4039
4040 if (cmd_len < sizeof(*req))
4041 return -EPROTO;
4042
4043 dcid = __le16_to_cpu(req->dcid);
4044 flags = __le16_to_cpu(req->flags);
4045
4046 BT_DBG("dcid 0x%4.4x flags 0x%2.2x", dcid, flags);
4047
4048 chan = l2cap_get_chan_by_scid(conn, dcid);
4049 if (!chan) {
4050 cmd_reject_invalid_cid(conn, cmd->ident, dcid, 0);
4051 return 0;
4052 }
4053
4054 if (chan->state != BT_CONFIG && chan->state != BT_CONNECT2) {
4055 cmd_reject_invalid_cid(conn, cmd->ident, chan->scid,
4056 chan->dcid);
4057 goto unlock;
4058 }
4059
4060 /* Reject if config buffer is too small. */
4061 len = cmd_len - sizeof(*req);
4062 if (chan->conf_len + len > sizeof(chan->conf_req)) {
4063 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP,
4064 l2cap_build_conf_rsp(chan, rsp,
4065 L2CAP_CONF_REJECT, flags), rsp);
4066 goto unlock;
4067 }
4068
4069 /* Store config. */
4070 memcpy(chan->conf_req + chan->conf_len, req->data, len);
4071 chan->conf_len += len;
4072
4073 if (flags & L2CAP_CONF_FLAG_CONTINUATION) {
4074 /* Incomplete config. Send empty response. */
4075 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP,
4076 l2cap_build_conf_rsp(chan, rsp,
4077 L2CAP_CONF_SUCCESS, flags), rsp);
4078 goto unlock;
4079 }
4080
4081 /* Complete config. */
4082 len = l2cap_parse_conf_req(chan, rsp);
4083 if (len < 0) {
4084 l2cap_send_disconn_req(chan, ECONNRESET);
4085 goto unlock;
4086 }
4087
4088 chan->ident = cmd->ident;
4089 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP, len, rsp);
4090 chan->num_conf_rsp++;
4091
4092 /* Reset config buffer. */
4093 chan->conf_len = 0;
4094
4095 if (!test_bit(CONF_OUTPUT_DONE, &chan->conf_state))
4096 goto unlock;
4097
4098 if (test_bit(CONF_INPUT_DONE, &chan->conf_state)) {
4099 set_default_fcs(chan);
4100
4101 if (chan->mode == L2CAP_MODE_ERTM ||
4102 chan->mode == L2CAP_MODE_STREAMING)
4103 err = l2cap_ertm_init(chan);
4104
4105 if (err < 0)
4106 l2cap_send_disconn_req(chan, -err);
4107 else
4108 l2cap_chan_ready(chan);
4109
4110 goto unlock;
4111 }
4112
4113 if (!test_and_set_bit(CONF_REQ_SENT, &chan->conf_state)) {
4114 u8 buf[64];
4115 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
4116 l2cap_build_conf_req(chan, buf), buf);
4117 chan->num_conf_req++;
4118 }
4119
4120 /* Got Conf Rsp PENDING from remote side and assume we sent
4121 Conf Rsp PENDING in the code above */
4122 if (test_bit(CONF_REM_CONF_PEND, &chan->conf_state) &&
4123 test_bit(CONF_LOC_CONF_PEND, &chan->conf_state)) {
4124
4125 /* check compatibility */
4126
4127 /* Send rsp for BR/EDR channel */
4128 if (!chan->hs_hcon)
4129 l2cap_send_efs_conf_rsp(chan, rsp, cmd->ident, flags);
4130 else
4131 chan->ident = cmd->ident;
4132 }
4133
4134unlock:
4135 l2cap_chan_unlock(chan);
4136 return err;
4137}
4138
4139static inline int l2cap_config_rsp(struct l2cap_conn *conn,
4140 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4141 u8 *data)
4142{
4143 struct l2cap_conf_rsp *rsp = (struct l2cap_conf_rsp *)data;
4144 u16 scid, flags, result;
4145 struct l2cap_chan *chan;
4146 int len = cmd_len - sizeof(*rsp);
4147 int err = 0;
4148
4149 if (cmd_len < sizeof(*rsp))
4150 return -EPROTO;
4151
4152 scid = __le16_to_cpu(rsp->scid);
4153 flags = __le16_to_cpu(rsp->flags);
4154 result = __le16_to_cpu(rsp->result);
4155
4156 BT_DBG("scid 0x%4.4x flags 0x%2.2x result 0x%2.2x len %d", scid, flags,
4157 result, len);
4158
4159 chan = l2cap_get_chan_by_scid(conn, scid);
4160 if (!chan)
4161 return 0;
4162
4163 switch (result) {
4164 case L2CAP_CONF_SUCCESS:
4165 l2cap_conf_rfc_get(chan, rsp->data, len);
4166 clear_bit(CONF_REM_CONF_PEND, &chan->conf_state);
4167 break;
4168
4169 case L2CAP_CONF_PENDING:
4170 set_bit(CONF_REM_CONF_PEND, &chan->conf_state);
4171
4172 if (test_bit(CONF_LOC_CONF_PEND, &chan->conf_state)) {
4173 char buf[64];
4174
4175 len = l2cap_parse_conf_rsp(chan, rsp->data, len,
4176 buf, &result);
4177 if (len < 0) {
4178 l2cap_send_disconn_req(chan, ECONNRESET);
4179 goto done;
4180 }
4181
4182 if (!chan->hs_hcon) {
4183 l2cap_send_efs_conf_rsp(chan, buf, cmd->ident,
4184 0);
4185 } else {
4186 if (l2cap_check_efs(chan)) {
4187 amp_create_logical_link(chan);
4188 chan->ident = cmd->ident;
4189 }
4190 }
4191 }
4192 goto done;
4193
4194 case L2CAP_CONF_UNACCEPT:
4195 if (chan->num_conf_rsp <= L2CAP_CONF_MAX_CONF_RSP) {
4196 char req[64];
4197
4198 if (len > sizeof(req) - sizeof(struct l2cap_conf_req)) {
4199 l2cap_send_disconn_req(chan, ECONNRESET);
4200 goto done;
4201 }
4202
4203 /* throw out any old stored conf requests */
4204 result = L2CAP_CONF_SUCCESS;
4205 len = l2cap_parse_conf_rsp(chan, rsp->data, len,
4206 req, &result);
4207 if (len < 0) {
4208 l2cap_send_disconn_req(chan, ECONNRESET);
4209 goto done;
4210 }
4211
4212 l2cap_send_cmd(conn, l2cap_get_ident(conn),
4213 L2CAP_CONF_REQ, len, req);
4214 chan->num_conf_req++;
4215 if (result != L2CAP_CONF_SUCCESS)
4216 goto done;
4217 break;
4218 }
4219
4220 default:
4221 l2cap_chan_set_err(chan, ECONNRESET);
4222
4223 __set_chan_timer(chan, L2CAP_DISC_REJ_TIMEOUT);
4224 l2cap_send_disconn_req(chan, ECONNRESET);
4225 goto done;
4226 }
4227
4228 if (flags & L2CAP_CONF_FLAG_CONTINUATION)
4229 goto done;
4230
4231 set_bit(CONF_INPUT_DONE, &chan->conf_state);
4232
4233 if (test_bit(CONF_OUTPUT_DONE, &chan->conf_state)) {
4234 set_default_fcs(chan);
4235
4236 if (chan->mode == L2CAP_MODE_ERTM ||
4237 chan->mode == L2CAP_MODE_STREAMING)
4238 err = l2cap_ertm_init(chan);
4239
4240 if (err < 0)
4241 l2cap_send_disconn_req(chan, -err);
4242 else
4243 l2cap_chan_ready(chan);
4244 }
4245
4246done:
4247 l2cap_chan_unlock(chan);
4248 return err;
4249}
4250
4251static inline int l2cap_disconnect_req(struct l2cap_conn *conn,
4252 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4253 u8 *data)
4254{
4255 struct l2cap_disconn_req *req = (struct l2cap_disconn_req *) data;
4256 struct l2cap_disconn_rsp rsp;
4257 u16 dcid, scid;
4258 struct l2cap_chan *chan;
4259
4260 if (cmd_len != sizeof(*req))
4261 return -EPROTO;
4262
4263 scid = __le16_to_cpu(req->scid);
4264 dcid = __le16_to_cpu(req->dcid);
4265
4266 BT_DBG("scid 0x%4.4x dcid 0x%4.4x", scid, dcid);
4267
4268 mutex_lock(&conn->chan_lock);
4269
4270 chan = __l2cap_get_chan_by_scid(conn, dcid);
4271 if (!chan) {
4272 mutex_unlock(&conn->chan_lock);
4273 cmd_reject_invalid_cid(conn, cmd->ident, dcid, scid);
4274 return 0;
4275 }
4276
4277 l2cap_chan_lock(chan);
4278
4279 rsp.dcid = cpu_to_le16(chan->scid);
4280 rsp.scid = cpu_to_le16(chan->dcid);
4281 l2cap_send_cmd(conn, cmd->ident, L2CAP_DISCONN_RSP, sizeof(rsp), &rsp);
4282
4283 chan->ops->set_shutdown(chan);
4284
4285 l2cap_chan_hold(chan);
4286 l2cap_chan_del(chan, ECONNRESET);
4287
4288 l2cap_chan_unlock(chan);
4289
4290 chan->ops->close(chan);
4291 l2cap_chan_put(chan);
4292
4293 mutex_unlock(&conn->chan_lock);
4294
4295 return 0;
4296}
4297
4298static inline int l2cap_disconnect_rsp(struct l2cap_conn *conn,
4299 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4300 u8 *data)
4301{
4302 struct l2cap_disconn_rsp *rsp = (struct l2cap_disconn_rsp *) data;
4303 u16 dcid, scid;
4304 struct l2cap_chan *chan;
4305
4306 if (cmd_len != sizeof(*rsp))
4307 return -EPROTO;
4308
4309 scid = __le16_to_cpu(rsp->scid);
4310 dcid = __le16_to_cpu(rsp->dcid);
4311
4312 BT_DBG("dcid 0x%4.4x scid 0x%4.4x", dcid, scid);
4313
4314 mutex_lock(&conn->chan_lock);
4315
4316 chan = __l2cap_get_chan_by_scid(conn, scid);
4317 if (!chan) {
4318 mutex_unlock(&conn->chan_lock);
4319 return 0;
4320 }
4321
4322 l2cap_chan_lock(chan);
4323
4324 l2cap_chan_hold(chan);
4325 l2cap_chan_del(chan, 0);
4326
4327 l2cap_chan_unlock(chan);
4328
4329 chan->ops->close(chan);
4330 l2cap_chan_put(chan);
4331
4332 mutex_unlock(&conn->chan_lock);
4333
4334 return 0;
4335}
4336
4337static inline int l2cap_information_req(struct l2cap_conn *conn,
4338 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4339 u8 *data)
4340{
4341 struct l2cap_info_req *req = (struct l2cap_info_req *) data;
4342 u16 type;
4343
4344 if (cmd_len != sizeof(*req))
4345 return -EPROTO;
4346
4347 type = __le16_to_cpu(req->type);
4348
4349 BT_DBG("type 0x%4.4x", type);
4350
4351 if (type == L2CAP_IT_FEAT_MASK) {
4352 u8 buf[8];
4353 u32 feat_mask = l2cap_feat_mask;
4354 struct l2cap_info_rsp *rsp = (struct l2cap_info_rsp *) buf;
4355 rsp->type = cpu_to_le16(L2CAP_IT_FEAT_MASK);
4356 rsp->result = cpu_to_le16(L2CAP_IR_SUCCESS);
4357 if (!disable_ertm)
4358 feat_mask |= L2CAP_FEAT_ERTM | L2CAP_FEAT_STREAMING
4359 | L2CAP_FEAT_FCS;
4360 if (conn->local_fixed_chan & L2CAP_FC_A2MP)
4361 feat_mask |= L2CAP_FEAT_EXT_FLOW
4362 | L2CAP_FEAT_EXT_WINDOW;
4363
4364 put_unaligned_le32(feat_mask, rsp->data);
4365 l2cap_send_cmd(conn, cmd->ident, L2CAP_INFO_RSP, sizeof(buf),
4366 buf);
4367 } else if (type == L2CAP_IT_FIXED_CHAN) {
4368 u8 buf[12];
4369 struct l2cap_info_rsp *rsp = (struct l2cap_info_rsp *) buf;
4370
4371 rsp->type = cpu_to_le16(L2CAP_IT_FIXED_CHAN);
4372 rsp->result = cpu_to_le16(L2CAP_IR_SUCCESS);
4373 rsp->data[0] = conn->local_fixed_chan;
4374 memset(rsp->data + 1, 0, 7);
4375 l2cap_send_cmd(conn, cmd->ident, L2CAP_INFO_RSP, sizeof(buf),
4376 buf);
4377 } else {
4378 struct l2cap_info_rsp rsp;
4379 rsp.type = cpu_to_le16(type);
4380 rsp.result = cpu_to_le16(L2CAP_IR_NOTSUPP);
4381 l2cap_send_cmd(conn, cmd->ident, L2CAP_INFO_RSP, sizeof(rsp),
4382 &rsp);
4383 }
4384
4385 return 0;
4386}
4387
4388static inline int l2cap_information_rsp(struct l2cap_conn *conn,
4389 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4390 u8 *data)
4391{
4392 struct l2cap_info_rsp *rsp = (struct l2cap_info_rsp *) data;
4393 u16 type, result;
4394
4395 if (cmd_len < sizeof(*rsp))
4396 return -EPROTO;
4397
4398 type = __le16_to_cpu(rsp->type);
4399 result = __le16_to_cpu(rsp->result);
4400
4401 BT_DBG("type 0x%4.4x result 0x%2.2x", type, result);
4402
4403 /* L2CAP Info req/rsp are unbound to channels, add extra checks */
4404 if (cmd->ident != conn->info_ident ||
4405 conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE)
4406 return 0;
4407
4408 cancel_delayed_work(&conn->info_timer);
4409
4410 if (result != L2CAP_IR_SUCCESS) {
4411 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
4412 conn->info_ident = 0;
4413
4414 l2cap_conn_start(conn);
4415
4416 return 0;
4417 }
4418
4419 switch (type) {
4420 case L2CAP_IT_FEAT_MASK:
4421 conn->feat_mask = get_unaligned_le32(rsp->data);
4422
4423 if (conn->feat_mask & L2CAP_FEAT_FIXED_CHAN) {
4424 struct l2cap_info_req req;
4425 req.type = cpu_to_le16(L2CAP_IT_FIXED_CHAN);
4426
4427 conn->info_ident = l2cap_get_ident(conn);
4428
4429 l2cap_send_cmd(conn, conn->info_ident,
4430 L2CAP_INFO_REQ, sizeof(req), &req);
4431 } else {
4432 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
4433 conn->info_ident = 0;
4434
4435 l2cap_conn_start(conn);
4436 }
4437 break;
4438
4439 case L2CAP_IT_FIXED_CHAN:
4440 conn->remote_fixed_chan = rsp->data[0];
4441 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
4442 conn->info_ident = 0;
4443
4444 l2cap_conn_start(conn);
4445 break;
4446 }
4447
4448 return 0;
4449}
4450
4451static int l2cap_create_channel_req(struct l2cap_conn *conn,
4452 struct l2cap_cmd_hdr *cmd,
4453 u16 cmd_len, void *data)
4454{
4455 struct l2cap_create_chan_req *req = data;
4456 struct l2cap_create_chan_rsp rsp;
4457 struct l2cap_chan *chan;
4458 struct hci_dev *hdev;
4459 u16 psm, scid;
4460
4461 if (cmd_len != sizeof(*req))
4462 return -EPROTO;
4463
4464 if (!(conn->local_fixed_chan & L2CAP_FC_A2MP))
4465 return -EINVAL;
4466
4467 psm = le16_to_cpu(req->psm);
4468 scid = le16_to_cpu(req->scid);
4469
4470 BT_DBG("psm 0x%2.2x, scid 0x%4.4x, amp_id %d", psm, scid, req->amp_id);
4471
4472 /* For controller id 0 make BR/EDR connection */
4473 if (req->amp_id == AMP_ID_BREDR) {
4474 l2cap_connect(conn, cmd, data, L2CAP_CREATE_CHAN_RSP,
4475 req->amp_id);
4476 return 0;
4477 }
4478
4479 /* Validate AMP controller id */
4480 hdev = hci_dev_get(req->amp_id);
4481 if (!hdev)
4482 goto error;
4483
4484 if (hdev->dev_type != HCI_AMP || !test_bit(HCI_UP, &hdev->flags)) {
4485 hci_dev_put(hdev);
4486 goto error;
4487 }
4488
4489 chan = l2cap_connect(conn, cmd, data, L2CAP_CREATE_CHAN_RSP,
4490 req->amp_id);
4491 if (chan) {
4492 struct amp_mgr *mgr = conn->hcon->amp_mgr;
4493 struct hci_conn *hs_hcon;
4494
4495 hs_hcon = hci_conn_hash_lookup_ba(hdev, AMP_LINK,
4496 &conn->hcon->dst);
4497 if (!hs_hcon) {
4498 hci_dev_put(hdev);
4499 cmd_reject_invalid_cid(conn, cmd->ident, chan->scid,
4500 chan->dcid);
4501 return 0;
4502 }
4503
4504 BT_DBG("mgr %p bredr_chan %p hs_hcon %p", mgr, chan, hs_hcon);
4505
4506 mgr->bredr_chan = chan;
4507 chan->hs_hcon = hs_hcon;
4508 chan->fcs = L2CAP_FCS_NONE;
4509 conn->mtu = hdev->block_mtu;
4510 }
4511
4512 hci_dev_put(hdev);
4513
4514 return 0;
4515
4516error:
4517 rsp.dcid = 0;
4518 rsp.scid = cpu_to_le16(scid);
4519 rsp.result = cpu_to_le16(L2CAP_CR_BAD_AMP);
4520 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
4521
4522 l2cap_send_cmd(conn, cmd->ident, L2CAP_CREATE_CHAN_RSP,
4523 sizeof(rsp), &rsp);
4524
4525 return 0;
4526}
4527
4528static void l2cap_send_move_chan_req(struct l2cap_chan *chan, u8 dest_amp_id)
4529{
4530 struct l2cap_move_chan_req req;
4531 u8 ident;
4532
4533 BT_DBG("chan %p, dest_amp_id %d", chan, dest_amp_id);
4534
4535 ident = l2cap_get_ident(chan->conn);
4536 chan->ident = ident;
4537
4538 req.icid = cpu_to_le16(chan->scid);
4539 req.dest_amp_id = dest_amp_id;
4540
4541 l2cap_send_cmd(chan->conn, ident, L2CAP_MOVE_CHAN_REQ, sizeof(req),
4542 &req);
4543
4544 __set_chan_timer(chan, L2CAP_MOVE_TIMEOUT);
4545}
4546
4547static void l2cap_send_move_chan_rsp(struct l2cap_chan *chan, u16 result)
4548{
4549 struct l2cap_move_chan_rsp rsp;
4550
4551 BT_DBG("chan %p, result 0x%4.4x", chan, result);
4552
4553 rsp.icid = cpu_to_le16(chan->dcid);
4554 rsp.result = cpu_to_le16(result);
4555
4556 l2cap_send_cmd(chan->conn, chan->ident, L2CAP_MOVE_CHAN_RSP,
4557 sizeof(rsp), &rsp);
4558}
4559
4560static void l2cap_send_move_chan_cfm(struct l2cap_chan *chan, u16 result)
4561{
4562 struct l2cap_move_chan_cfm cfm;
4563
4564 BT_DBG("chan %p, result 0x%4.4x", chan, result);
4565
4566 chan->ident = l2cap_get_ident(chan->conn);
4567
4568 cfm.icid = cpu_to_le16(chan->scid);
4569 cfm.result = cpu_to_le16(result);
4570
4571 l2cap_send_cmd(chan->conn, chan->ident, L2CAP_MOVE_CHAN_CFM,
4572 sizeof(cfm), &cfm);
4573
4574 __set_chan_timer(chan, L2CAP_MOVE_TIMEOUT);
4575}
4576
4577static void l2cap_send_move_chan_cfm_icid(struct l2cap_conn *conn, u16 icid)
4578{
4579 struct l2cap_move_chan_cfm cfm;
4580
4581 BT_DBG("conn %p, icid 0x%4.4x", conn, icid);
4582
4583 cfm.icid = cpu_to_le16(icid);
4584 cfm.result = cpu_to_le16(L2CAP_MC_UNCONFIRMED);
4585
4586 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_MOVE_CHAN_CFM,
4587 sizeof(cfm), &cfm);
4588}
4589
4590static void l2cap_send_move_chan_cfm_rsp(struct l2cap_conn *conn, u8 ident,
4591 u16 icid)
4592{
4593 struct l2cap_move_chan_cfm_rsp rsp;
4594
4595 BT_DBG("icid 0x%4.4x", icid);
4596
4597 rsp.icid = cpu_to_le16(icid);
4598 l2cap_send_cmd(conn, ident, L2CAP_MOVE_CHAN_CFM_RSP, sizeof(rsp), &rsp);
4599}
4600
4601static void __release_logical_link(struct l2cap_chan *chan)
4602{
4603 chan->hs_hchan = NULL;
4604 chan->hs_hcon = NULL;
4605
4606 /* Placeholder - release the logical link */
4607}
4608
4609static void l2cap_logical_fail(struct l2cap_chan *chan)
4610{
4611 /* Logical link setup failed */
4612 if (chan->state != BT_CONNECTED) {
4613 /* Create channel failure, disconnect */
4614 l2cap_send_disconn_req(chan, ECONNRESET);
4615 return;
4616 }
4617
4618 switch (chan->move_role) {
4619 case L2CAP_MOVE_ROLE_RESPONDER:
4620 l2cap_move_done(chan);
4621 l2cap_send_move_chan_rsp(chan, L2CAP_MR_NOT_SUPP);
4622 break;
4623 case L2CAP_MOVE_ROLE_INITIATOR:
4624 if (chan->move_state == L2CAP_MOVE_WAIT_LOGICAL_COMP ||
4625 chan->move_state == L2CAP_MOVE_WAIT_LOGICAL_CFM) {
4626 /* Remote has only sent pending or
4627 * success responses, clean up
4628 */
4629 l2cap_move_done(chan);
4630 }
4631
4632 /* Other amp move states imply that the move
4633 * has already aborted
4634 */
4635 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
4636 break;
4637 }
4638}
4639
4640static void l2cap_logical_finish_create(struct l2cap_chan *chan,
4641 struct hci_chan *hchan)
4642{
4643 struct l2cap_conf_rsp rsp;
4644
4645 chan->hs_hchan = hchan;
4646 chan->hs_hcon->l2cap_data = chan->conn;
4647
4648 l2cap_send_efs_conf_rsp(chan, &rsp, chan->ident, 0);
4649
4650 if (test_bit(CONF_INPUT_DONE, &chan->conf_state)) {
4651 int err;
4652
4653 set_default_fcs(chan);
4654
4655 err = l2cap_ertm_init(chan);
4656 if (err < 0)
4657 l2cap_send_disconn_req(chan, -err);
4658 else
4659 l2cap_chan_ready(chan);
4660 }
4661}
4662
4663static void l2cap_logical_finish_move(struct l2cap_chan *chan,
4664 struct hci_chan *hchan)
4665{
4666 chan->hs_hcon = hchan->conn;
4667 chan->hs_hcon->l2cap_data = chan->conn;
4668
4669 BT_DBG("move_state %d", chan->move_state);
4670
4671 switch (chan->move_state) {
4672 case L2CAP_MOVE_WAIT_LOGICAL_COMP:
4673 /* Move confirm will be sent after a success
4674 * response is received
4675 */
4676 chan->move_state = L2CAP_MOVE_WAIT_RSP_SUCCESS;
4677 break;
4678 case L2CAP_MOVE_WAIT_LOGICAL_CFM:
4679 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
4680 chan->move_state = L2CAP_MOVE_WAIT_LOCAL_BUSY;
4681 } else if (chan->move_role == L2CAP_MOVE_ROLE_INITIATOR) {
4682 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM_RSP;
4683 l2cap_send_move_chan_cfm(chan, L2CAP_MC_CONFIRMED);
4684 } else if (chan->move_role == L2CAP_MOVE_ROLE_RESPONDER) {
4685 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM;
4686 l2cap_send_move_chan_rsp(chan, L2CAP_MR_SUCCESS);
4687 }
4688 break;
4689 default:
4690 /* Move was not in expected state, free the channel */
4691 __release_logical_link(chan);
4692
4693 chan->move_state = L2CAP_MOVE_STABLE;
4694 }
4695}
4696
4697/* Call with chan locked */
4698void l2cap_logical_cfm(struct l2cap_chan *chan, struct hci_chan *hchan,
4699 u8 status)
4700{
4701 BT_DBG("chan %p, hchan %p, status %d", chan, hchan, status);
4702
4703 if (status) {
4704 l2cap_logical_fail(chan);
4705 __release_logical_link(chan);
4706 return;
4707 }
4708
4709 if (chan->state != BT_CONNECTED) {
4710 /* Ignore logical link if channel is on BR/EDR */
4711 if (chan->local_amp_id != AMP_ID_BREDR)
4712 l2cap_logical_finish_create(chan, hchan);
4713 } else {
4714 l2cap_logical_finish_move(chan, hchan);
4715 }
4716}
4717
4718void l2cap_move_start(struct l2cap_chan *chan)
4719{
4720 BT_DBG("chan %p", chan);
4721
4722 if (chan->local_amp_id == AMP_ID_BREDR) {
4723 if (chan->chan_policy != BT_CHANNEL_POLICY_AMP_PREFERRED)
4724 return;
4725 chan->move_role = L2CAP_MOVE_ROLE_INITIATOR;
4726 chan->move_state = L2CAP_MOVE_WAIT_PREPARE;
4727 /* Placeholder - start physical link setup */
4728 } else {
4729 chan->move_role = L2CAP_MOVE_ROLE_INITIATOR;
4730 chan->move_state = L2CAP_MOVE_WAIT_RSP_SUCCESS;
4731 chan->move_id = 0;
4732 l2cap_move_setup(chan);
4733 l2cap_send_move_chan_req(chan, 0);
4734 }
4735}
4736
4737static void l2cap_do_create(struct l2cap_chan *chan, int result,
4738 u8 local_amp_id, u8 remote_amp_id)
4739{
4740 BT_DBG("chan %p state %s %u -> %u", chan, state_to_string(chan->state),
4741 local_amp_id, remote_amp_id);
4742
4743 chan->fcs = L2CAP_FCS_NONE;
4744
4745 /* Outgoing channel on AMP */
4746 if (chan->state == BT_CONNECT) {
4747 if (result == L2CAP_CR_SUCCESS) {
4748 chan->local_amp_id = local_amp_id;
4749 l2cap_send_create_chan_req(chan, remote_amp_id);
4750 } else {
4751 /* Revert to BR/EDR connect */
4752 l2cap_send_conn_req(chan);
4753 }
4754
4755 return;
4756 }
4757
4758 /* Incoming channel on AMP */
4759 if (__l2cap_no_conn_pending(chan)) {
4760 struct l2cap_conn_rsp rsp;
4761 char buf[128];
4762 rsp.scid = cpu_to_le16(chan->dcid);
4763 rsp.dcid = cpu_to_le16(chan->scid);
4764
4765 if (result == L2CAP_CR_SUCCESS) {
4766 /* Send successful response */
4767 rsp.result = cpu_to_le16(L2CAP_CR_SUCCESS);
4768 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
4769 } else {
4770 /* Send negative response */
4771 rsp.result = cpu_to_le16(L2CAP_CR_NO_MEM);
4772 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
4773 }
4774
4775 l2cap_send_cmd(chan->conn, chan->ident, L2CAP_CREATE_CHAN_RSP,
4776 sizeof(rsp), &rsp);
4777
4778 if (result == L2CAP_CR_SUCCESS) {
4779 l2cap_state_change(chan, BT_CONFIG);
4780 set_bit(CONF_REQ_SENT, &chan->conf_state);
4781 l2cap_send_cmd(chan->conn, l2cap_get_ident(chan->conn),
4782 L2CAP_CONF_REQ,
4783 l2cap_build_conf_req(chan, buf), buf);
4784 chan->num_conf_req++;
4785 }
4786 }
4787}
4788
4789static void l2cap_do_move_initiate(struct l2cap_chan *chan, u8 local_amp_id,
4790 u8 remote_amp_id)
4791{
4792 l2cap_move_setup(chan);
4793 chan->move_id = local_amp_id;
4794 chan->move_state = L2CAP_MOVE_WAIT_RSP;
4795
4796 l2cap_send_move_chan_req(chan, remote_amp_id);
4797}
4798
4799static void l2cap_do_move_respond(struct l2cap_chan *chan, int result)
4800{
4801 struct hci_chan *hchan = NULL;
4802
4803 /* Placeholder - get hci_chan for logical link */
4804
4805 if (hchan) {
4806 if (hchan->state == BT_CONNECTED) {
4807 /* Logical link is ready to go */
4808 chan->hs_hcon = hchan->conn;
4809 chan->hs_hcon->l2cap_data = chan->conn;
4810 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM;
4811 l2cap_send_move_chan_rsp(chan, L2CAP_MR_SUCCESS);
4812
4813 l2cap_logical_cfm(chan, hchan, L2CAP_MR_SUCCESS);
4814 } else {
4815 /* Wait for logical link to be ready */
4816 chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_CFM;
4817 }
4818 } else {
4819 /* Logical link not available */
4820 l2cap_send_move_chan_rsp(chan, L2CAP_MR_NOT_ALLOWED);
4821 }
4822}
4823
4824static void l2cap_do_move_cancel(struct l2cap_chan *chan, int result)
4825{
4826 if (chan->move_role == L2CAP_MOVE_ROLE_RESPONDER) {
4827 u8 rsp_result;
4828 if (result == -EINVAL)
4829 rsp_result = L2CAP_MR_BAD_ID;
4830 else
4831 rsp_result = L2CAP_MR_NOT_ALLOWED;
4832
4833 l2cap_send_move_chan_rsp(chan, rsp_result);
4834 }
4835
4836 chan->move_role = L2CAP_MOVE_ROLE_NONE;
4837 chan->move_state = L2CAP_MOVE_STABLE;
4838
4839 /* Restart data transmission */
4840 l2cap_ertm_send(chan);
4841}
4842
4843/* Invoke with locked chan */
4844void __l2cap_physical_cfm(struct l2cap_chan *chan, int result)
4845{
4846 u8 local_amp_id = chan->local_amp_id;
4847 u8 remote_amp_id = chan->remote_amp_id;
4848
4849 BT_DBG("chan %p, result %d, local_amp_id %d, remote_amp_id %d",
4850 chan, result, local_amp_id, remote_amp_id);
4851
4852 if (chan->state == BT_DISCONN || chan->state == BT_CLOSED) {
4853 l2cap_chan_unlock(chan);
4854 return;
4855 }
4856
4857 if (chan->state != BT_CONNECTED) {
4858 l2cap_do_create(chan, result, local_amp_id, remote_amp_id);
4859 } else if (result != L2CAP_MR_SUCCESS) {
4860 l2cap_do_move_cancel(chan, result);
4861 } else {
4862 switch (chan->move_role) {
4863 case L2CAP_MOVE_ROLE_INITIATOR:
4864 l2cap_do_move_initiate(chan, local_amp_id,
4865 remote_amp_id);
4866 break;
4867 case L2CAP_MOVE_ROLE_RESPONDER:
4868 l2cap_do_move_respond(chan, result);
4869 break;
4870 default:
4871 l2cap_do_move_cancel(chan, result);
4872 break;
4873 }
4874 }
4875}
4876
4877static inline int l2cap_move_channel_req(struct l2cap_conn *conn,
4878 struct l2cap_cmd_hdr *cmd,
4879 u16 cmd_len, void *data)
4880{
4881 struct l2cap_move_chan_req *req = data;
4882 struct l2cap_move_chan_rsp rsp;
4883 struct l2cap_chan *chan;
4884 u16 icid = 0;
4885 u16 result = L2CAP_MR_NOT_ALLOWED;
4886
4887 if (cmd_len != sizeof(*req))
4888 return -EPROTO;
4889
4890 icid = le16_to_cpu(req->icid);
4891
4892 BT_DBG("icid 0x%4.4x, dest_amp_id %d", icid, req->dest_amp_id);
4893
4894 if (!(conn->local_fixed_chan & L2CAP_FC_A2MP))
4895 return -EINVAL;
4896
4897 chan = l2cap_get_chan_by_dcid(conn, icid);
4898 if (!chan) {
4899 rsp.icid = cpu_to_le16(icid);
4900 rsp.result = cpu_to_le16(L2CAP_MR_NOT_ALLOWED);
4901 l2cap_send_cmd(conn, cmd->ident, L2CAP_MOVE_CHAN_RSP,
4902 sizeof(rsp), &rsp);
4903 return 0;
4904 }
4905
4906 chan->ident = cmd->ident;
4907
4908 if (chan->scid < L2CAP_CID_DYN_START ||
4909 chan->chan_policy == BT_CHANNEL_POLICY_BREDR_ONLY ||
4910 (chan->mode != L2CAP_MODE_ERTM &&
4911 chan->mode != L2CAP_MODE_STREAMING)) {
4912 result = L2CAP_MR_NOT_ALLOWED;
4913 goto send_move_response;
4914 }
4915
4916 if (chan->local_amp_id == req->dest_amp_id) {
4917 result = L2CAP_MR_SAME_ID;
4918 goto send_move_response;
4919 }
4920
4921 if (req->dest_amp_id != AMP_ID_BREDR) {
4922 struct hci_dev *hdev;
4923 hdev = hci_dev_get(req->dest_amp_id);
4924 if (!hdev || hdev->dev_type != HCI_AMP ||
4925 !test_bit(HCI_UP, &hdev->flags)) {
4926 if (hdev)
4927 hci_dev_put(hdev);
4928
4929 result = L2CAP_MR_BAD_ID;
4930 goto send_move_response;
4931 }
4932 hci_dev_put(hdev);
4933 }
4934
4935 /* Detect a move collision. Only send a collision response
4936 * if this side has "lost", otherwise proceed with the move.
4937 * The winner has the larger bd_addr.
4938 */
4939 if ((__chan_is_moving(chan) ||
4940 chan->move_role != L2CAP_MOVE_ROLE_NONE) &&
4941 bacmp(&conn->hcon->src, &conn->hcon->dst) > 0) {
4942 result = L2CAP_MR_COLLISION;
4943 goto send_move_response;
4944 }
4945
4946 chan->move_role = L2CAP_MOVE_ROLE_RESPONDER;
4947 l2cap_move_setup(chan);
4948 chan->move_id = req->dest_amp_id;
4949 icid = chan->dcid;
4950
4951 if (req->dest_amp_id == AMP_ID_BREDR) {
4952 /* Moving to BR/EDR */
4953 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
4954 chan->move_state = L2CAP_MOVE_WAIT_LOCAL_BUSY;
4955 result = L2CAP_MR_PEND;
4956 } else {
4957 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM;
4958 result = L2CAP_MR_SUCCESS;
4959 }
4960 } else {
4961 chan->move_state = L2CAP_MOVE_WAIT_PREPARE;
4962 /* Placeholder - uncomment when amp functions are available */
4963 /*amp_accept_physical(chan, req->dest_amp_id);*/
4964 result = L2CAP_MR_PEND;
4965 }
4966
4967send_move_response:
4968 l2cap_send_move_chan_rsp(chan, result);
4969
4970 l2cap_chan_unlock(chan);
4971
4972 return 0;
4973}
4974
4975static void l2cap_move_continue(struct l2cap_conn *conn, u16 icid, u16 result)
4976{
4977 struct l2cap_chan *chan;
4978 struct hci_chan *hchan = NULL;
4979
4980 chan = l2cap_get_chan_by_scid(conn, icid);
4981 if (!chan) {
4982 l2cap_send_move_chan_cfm_icid(conn, icid);
4983 return;
4984 }
4985
4986 __clear_chan_timer(chan);
4987 if (result == L2CAP_MR_PEND)
4988 __set_chan_timer(chan, L2CAP_MOVE_ERTX_TIMEOUT);
4989
4990 switch (chan->move_state) {
4991 case L2CAP_MOVE_WAIT_LOGICAL_COMP:
4992 /* Move confirm will be sent when logical link
4993 * is complete.
4994 */
4995 chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_CFM;
4996 break;
4997 case L2CAP_MOVE_WAIT_RSP_SUCCESS:
4998 if (result == L2CAP_MR_PEND) {
4999 break;
5000 } else if (test_bit(CONN_LOCAL_BUSY,
5001 &chan->conn_state)) {
5002 chan->move_state = L2CAP_MOVE_WAIT_LOCAL_BUSY;
5003 } else {
5004 /* Logical link is up or moving to BR/EDR,
5005 * proceed with move
5006 */
5007 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM_RSP;
5008 l2cap_send_move_chan_cfm(chan, L2CAP_MC_CONFIRMED);
5009 }
5010 break;
5011 case L2CAP_MOVE_WAIT_RSP:
5012 /* Moving to AMP */
5013 if (result == L2CAP_MR_SUCCESS) {
5014 /* Remote is ready, send confirm immediately
5015 * after logical link is ready
5016 */
5017 chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_CFM;
5018 } else {
5019 /* Both logical link and move success
5020 * are required to confirm
5021 */
5022 chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_COMP;
5023 }
5024
5025 /* Placeholder - get hci_chan for logical link */
5026 if (!hchan) {
5027 /* Logical link not available */
5028 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
5029 break;
5030 }
5031
5032 /* If the logical link is not yet connected, do not
5033 * send confirmation.
5034 */
5035 if (hchan->state != BT_CONNECTED)
5036 break;
5037
5038 /* Logical link is already ready to go */
5039
5040 chan->hs_hcon = hchan->conn;
5041 chan->hs_hcon->l2cap_data = chan->conn;
5042
5043 if (result == L2CAP_MR_SUCCESS) {
5044 /* Can confirm now */
5045 l2cap_send_move_chan_cfm(chan, L2CAP_MC_CONFIRMED);
5046 } else {
5047 /* Now only need move success
5048 * to confirm
5049 */
5050 chan->move_state = L2CAP_MOVE_WAIT_RSP_SUCCESS;
5051 }
5052
5053 l2cap_logical_cfm(chan, hchan, L2CAP_MR_SUCCESS);
5054 break;
5055 default:
5056 /* Any other amp move state means the move failed. */
5057 chan->move_id = chan->local_amp_id;
5058 l2cap_move_done(chan);
5059 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
5060 }
5061
5062 l2cap_chan_unlock(chan);
5063}
5064
5065static void l2cap_move_fail(struct l2cap_conn *conn, u8 ident, u16 icid,
5066 u16 result)
5067{
5068 struct l2cap_chan *chan;
5069
5070 chan = l2cap_get_chan_by_ident(conn, ident);
5071 if (!chan) {
5072 /* Could not locate channel, icid is best guess */
5073 l2cap_send_move_chan_cfm_icid(conn, icid);
5074 return;
5075 }
5076
5077 __clear_chan_timer(chan);
5078
5079 if (chan->move_role == L2CAP_MOVE_ROLE_INITIATOR) {
5080 if (result == L2CAP_MR_COLLISION) {
5081 chan->move_role = L2CAP_MOVE_ROLE_RESPONDER;
5082 } else {
5083 /* Cleanup - cancel move */
5084 chan->move_id = chan->local_amp_id;
5085 l2cap_move_done(chan);
5086 }
5087 }
5088
5089 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
5090
5091 l2cap_chan_unlock(chan);
5092}
5093
5094static int l2cap_move_channel_rsp(struct l2cap_conn *conn,
5095 struct l2cap_cmd_hdr *cmd,
5096 u16 cmd_len, void *data)
5097{
5098 struct l2cap_move_chan_rsp *rsp = data;
5099 u16 icid, result;
5100
5101 if (cmd_len != sizeof(*rsp))
5102 return -EPROTO;
5103
5104 icid = le16_to_cpu(rsp->icid);
5105 result = le16_to_cpu(rsp->result);
5106
5107 BT_DBG("icid 0x%4.4x, result 0x%4.4x", icid, result);
5108
5109 if (result == L2CAP_MR_SUCCESS || result == L2CAP_MR_PEND)
5110 l2cap_move_continue(conn, icid, result);
5111 else
5112 l2cap_move_fail(conn, cmd->ident, icid, result);
5113
5114 return 0;
5115}
5116
5117static int l2cap_move_channel_confirm(struct l2cap_conn *conn,
5118 struct l2cap_cmd_hdr *cmd,
5119 u16 cmd_len, void *data)
5120{
5121 struct l2cap_move_chan_cfm *cfm = data;
5122 struct l2cap_chan *chan;
5123 u16 icid, result;
5124
5125 if (cmd_len != sizeof(*cfm))
5126 return -EPROTO;
5127
5128 icid = le16_to_cpu(cfm->icid);
5129 result = le16_to_cpu(cfm->result);
5130
5131 BT_DBG("icid 0x%4.4x, result 0x%4.4x", icid, result);
5132
5133 chan = l2cap_get_chan_by_dcid(conn, icid);
5134 if (!chan) {
5135 /* Spec requires a response even if the icid was not found */
5136 l2cap_send_move_chan_cfm_rsp(conn, cmd->ident, icid);
5137 return 0;
5138 }
5139
5140 if (chan->move_state == L2CAP_MOVE_WAIT_CONFIRM) {
5141 if (result == L2CAP_MC_CONFIRMED) {
5142 chan->local_amp_id = chan->move_id;
5143 if (chan->local_amp_id == AMP_ID_BREDR)
5144 __release_logical_link(chan);
5145 } else {
5146 chan->move_id = chan->local_amp_id;
5147 }
5148
5149 l2cap_move_done(chan);
5150 }
5151
5152 l2cap_send_move_chan_cfm_rsp(conn, cmd->ident, icid);
5153
5154 l2cap_chan_unlock(chan);
5155
5156 return 0;
5157}
5158
5159static inline int l2cap_move_channel_confirm_rsp(struct l2cap_conn *conn,
5160 struct l2cap_cmd_hdr *cmd,
5161 u16 cmd_len, void *data)
5162{
5163 struct l2cap_move_chan_cfm_rsp *rsp = data;
5164 struct l2cap_chan *chan;
5165 u16 icid;
5166
5167 if (cmd_len != sizeof(*rsp))
5168 return -EPROTO;
5169
5170 icid = le16_to_cpu(rsp->icid);
5171
5172 BT_DBG("icid 0x%4.4x", icid);
5173
5174 chan = l2cap_get_chan_by_scid(conn, icid);
5175 if (!chan)
5176 return 0;
5177
5178 __clear_chan_timer(chan);
5179
5180 if (chan->move_state == L2CAP_MOVE_WAIT_CONFIRM_RSP) {
5181 chan->local_amp_id = chan->move_id;
5182
5183 if (chan->local_amp_id == AMP_ID_BREDR && chan->hs_hchan)
5184 __release_logical_link(chan);
5185
5186 l2cap_move_done(chan);
5187 }
5188
5189 l2cap_chan_unlock(chan);
5190
5191 return 0;
5192}
5193
5194static inline int l2cap_conn_param_update_req(struct l2cap_conn *conn,
5195 struct l2cap_cmd_hdr *cmd,
5196 u16 cmd_len, u8 *data)
5197{
5198 struct hci_conn *hcon = conn->hcon;
5199 struct l2cap_conn_param_update_req *req;
5200 struct l2cap_conn_param_update_rsp rsp;
5201 u16 min, max, latency, to_multiplier;
5202 int err;
5203
5204 if (hcon->role != HCI_ROLE_MASTER)
5205 return -EINVAL;
5206
5207 if (cmd_len != sizeof(struct l2cap_conn_param_update_req))
5208 return -EPROTO;
5209
5210 req = (struct l2cap_conn_param_update_req *) data;
5211 min = __le16_to_cpu(req->min);
5212 max = __le16_to_cpu(req->max);
5213 latency = __le16_to_cpu(req->latency);
5214 to_multiplier = __le16_to_cpu(req->to_multiplier);
5215
5216 BT_DBG("min 0x%4.4x max 0x%4.4x latency: 0x%4.4x Timeout: 0x%4.4x",
5217 min, max, latency, to_multiplier);
5218
5219 memset(&rsp, 0, sizeof(rsp));
5220
5221 err = hci_check_conn_params(min, max, latency, to_multiplier);
5222 if (err)
5223 rsp.result = cpu_to_le16(L2CAP_CONN_PARAM_REJECTED);
5224 else
5225 rsp.result = cpu_to_le16(L2CAP_CONN_PARAM_ACCEPTED);
5226
5227 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONN_PARAM_UPDATE_RSP,
5228 sizeof(rsp), &rsp);
5229
5230 if (!err) {
5231 u8 store_hint;
5232
5233 store_hint = hci_le_conn_update(hcon, min, max, latency,
5234 to_multiplier);
5235 mgmt_new_conn_param(hcon->hdev, &hcon->dst, hcon->dst_type,
5236 store_hint, min, max, latency,
5237 to_multiplier);
5238
5239 }
5240
5241 return 0;
5242}
5243
5244static int l2cap_le_connect_rsp(struct l2cap_conn *conn,
5245 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5246 u8 *data)
5247{
5248 struct l2cap_le_conn_rsp *rsp = (struct l2cap_le_conn_rsp *) data;
5249 struct hci_conn *hcon = conn->hcon;
5250 u16 dcid, mtu, mps, credits, result;
5251 struct l2cap_chan *chan;
5252 int err, sec_level;
5253
5254 if (cmd_len < sizeof(*rsp))
5255 return -EPROTO;
5256
5257 dcid = __le16_to_cpu(rsp->dcid);
5258 mtu = __le16_to_cpu(rsp->mtu);
5259 mps = __le16_to_cpu(rsp->mps);
5260 credits = __le16_to_cpu(rsp->credits);
5261 result = __le16_to_cpu(rsp->result);
5262
5263 if (result == L2CAP_CR_SUCCESS && (mtu < 23 || mps < 23 ||
5264 dcid < L2CAP_CID_DYN_START ||
5265 dcid > L2CAP_CID_LE_DYN_END))
5266 return -EPROTO;
5267
5268 BT_DBG("dcid 0x%4.4x mtu %u mps %u credits %u result 0x%2.2x",
5269 dcid, mtu, mps, credits, result);
5270
5271 mutex_lock(&conn->chan_lock);
5272
5273 chan = __l2cap_get_chan_by_ident(conn, cmd->ident);
5274 if (!chan) {
5275 err = -EBADSLT;
5276 goto unlock;
5277 }
5278
5279 err = 0;
5280
5281 l2cap_chan_lock(chan);
5282
5283 switch (result) {
5284 case L2CAP_CR_SUCCESS:
5285 if (__l2cap_get_chan_by_dcid(conn, dcid)) {
5286 err = -EBADSLT;
5287 break;
5288 }
5289
5290 chan->ident = 0;
5291 chan->dcid = dcid;
5292 chan->omtu = mtu;
5293 chan->remote_mps = mps;
5294 chan->tx_credits = credits;
5295 l2cap_chan_ready(chan);
5296 break;
5297
5298 case L2CAP_CR_AUTHENTICATION:
5299 case L2CAP_CR_ENCRYPTION:
5300 /* If we already have MITM protection we can't do
5301 * anything.
5302 */
5303 if (hcon->sec_level > BT_SECURITY_MEDIUM) {
5304 l2cap_chan_del(chan, ECONNREFUSED);
5305 break;
5306 }
5307
5308 sec_level = hcon->sec_level + 1;
5309 if (chan->sec_level < sec_level)
5310 chan->sec_level = sec_level;
5311
5312 /* We'll need to send a new Connect Request */
5313 clear_bit(FLAG_LE_CONN_REQ_SENT, &chan->flags);
5314
5315 smp_conn_security(hcon, chan->sec_level);
5316 break;
5317
5318 default:
5319 l2cap_chan_del(chan, ECONNREFUSED);
5320 break;
5321 }
5322
5323 l2cap_chan_unlock(chan);
5324
5325unlock:
5326 mutex_unlock(&conn->chan_lock);
5327
5328 return err;
5329}
5330
5331static inline int l2cap_bredr_sig_cmd(struct l2cap_conn *conn,
5332 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5333 u8 *data)
5334{
5335 int err = 0;
5336
5337 switch (cmd->code) {
5338 case L2CAP_COMMAND_REJ:
5339 l2cap_command_rej(conn, cmd, cmd_len, data);
5340 break;
5341
5342 case L2CAP_CONN_REQ:
5343 err = l2cap_connect_req(conn, cmd, cmd_len, data);
5344 break;
5345
5346 case L2CAP_CONN_RSP:
5347 case L2CAP_CREATE_CHAN_RSP:
5348 l2cap_connect_create_rsp(conn, cmd, cmd_len, data);
5349 break;
5350
5351 case L2CAP_CONF_REQ:
5352 err = l2cap_config_req(conn, cmd, cmd_len, data);
5353 break;
5354
5355 case L2CAP_CONF_RSP:
5356 l2cap_config_rsp(conn, cmd, cmd_len, data);
5357 break;
5358
5359 case L2CAP_DISCONN_REQ:
5360 err = l2cap_disconnect_req(conn, cmd, cmd_len, data);
5361 break;
5362
5363 case L2CAP_DISCONN_RSP:
5364 l2cap_disconnect_rsp(conn, cmd, cmd_len, data);
5365 break;
5366
5367 case L2CAP_ECHO_REQ:
5368 l2cap_send_cmd(conn, cmd->ident, L2CAP_ECHO_RSP, cmd_len, data);
5369 break;
5370
5371 case L2CAP_ECHO_RSP:
5372 break;
5373
5374 case L2CAP_INFO_REQ:
5375 err = l2cap_information_req(conn, cmd, cmd_len, data);
5376 break;
5377
5378 case L2CAP_INFO_RSP:
5379 l2cap_information_rsp(conn, cmd, cmd_len, data);
5380 break;
5381
5382 case L2CAP_CREATE_CHAN_REQ:
5383 err = l2cap_create_channel_req(conn, cmd, cmd_len, data);
5384 break;
5385
5386 case L2CAP_MOVE_CHAN_REQ:
5387 err = l2cap_move_channel_req(conn, cmd, cmd_len, data);
5388 break;
5389
5390 case L2CAP_MOVE_CHAN_RSP:
5391 l2cap_move_channel_rsp(conn, cmd, cmd_len, data);
5392 break;
5393
5394 case L2CAP_MOVE_CHAN_CFM:
5395 err = l2cap_move_channel_confirm(conn, cmd, cmd_len, data);
5396 break;
5397
5398 case L2CAP_MOVE_CHAN_CFM_RSP:
5399 l2cap_move_channel_confirm_rsp(conn, cmd, cmd_len, data);
5400 break;
5401
5402 default:
5403 BT_ERR("Unknown BR/EDR signaling command 0x%2.2x", cmd->code);
5404 err = -EINVAL;
5405 break;
5406 }
5407
5408 return err;
5409}
5410
5411static int l2cap_le_connect_req(struct l2cap_conn *conn,
5412 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5413 u8 *data)
5414{
5415 struct l2cap_le_conn_req *req = (struct l2cap_le_conn_req *) data;
5416 struct l2cap_le_conn_rsp rsp;
5417 struct l2cap_chan *chan, *pchan;
5418 u16 dcid, scid, credits, mtu, mps;
5419 __le16 psm;
5420 u8 result;
5421
5422 if (cmd_len != sizeof(*req))
5423 return -EPROTO;
5424
5425 scid = __le16_to_cpu(req->scid);
5426 mtu = __le16_to_cpu(req->mtu);
5427 mps = __le16_to_cpu(req->mps);
5428 psm = req->psm;
5429 dcid = 0;
5430 credits = 0;
5431
5432 if (mtu < 23 || mps < 23)
5433 return -EPROTO;
5434
5435 BT_DBG("psm 0x%2.2x scid 0x%4.4x mtu %u mps %u", __le16_to_cpu(psm),
5436 scid, mtu, mps);
5437
5438 /* Check if we have socket listening on psm */
5439 pchan = l2cap_global_chan_by_psm(BT_LISTEN, psm, &conn->hcon->src,
5440 &conn->hcon->dst, LE_LINK);
5441 if (!pchan) {
5442 result = L2CAP_CR_BAD_PSM;
5443 chan = NULL;
5444 goto response;
5445 }
5446
5447 mutex_lock(&conn->chan_lock);
5448 l2cap_chan_lock(pchan);
5449
5450 if (!smp_sufficient_security(conn->hcon, pchan->sec_level,
5451 SMP_ALLOW_STK)) {
5452 result = L2CAP_CR_AUTHENTICATION;
5453 chan = NULL;
5454 goto response_unlock;
5455 }
5456
5457 /* Check for valid dynamic CID range */
5458 if (scid < L2CAP_CID_DYN_START || scid > L2CAP_CID_LE_DYN_END) {
5459 result = L2CAP_CR_INVALID_SCID;
5460 chan = NULL;
5461 goto response_unlock;
5462 }
5463
5464 /* Check if we already have channel with that dcid */
5465 if (__l2cap_get_chan_by_dcid(conn, scid)) {
5466 result = L2CAP_CR_SCID_IN_USE;
5467 chan = NULL;
5468 goto response_unlock;
5469 }
5470
5471 chan = pchan->ops->new_connection(pchan);
5472 if (!chan) {
5473 result = L2CAP_CR_NO_MEM;
5474 goto response_unlock;
5475 }
5476
5477 l2cap_le_flowctl_init(chan);
5478
5479 bacpy(&chan->src, &conn->hcon->src);
5480 bacpy(&chan->dst, &conn->hcon->dst);
5481 chan->src_type = bdaddr_src_type(conn->hcon);
5482 chan->dst_type = bdaddr_dst_type(conn->hcon);
5483 chan->psm = psm;
5484 chan->dcid = scid;
5485 chan->omtu = mtu;
5486 chan->remote_mps = mps;
5487 chan->tx_credits = __le16_to_cpu(req->credits);
5488
5489 __l2cap_chan_add(conn, chan);
5490 dcid = chan->scid;
5491 credits = chan->rx_credits;
5492
5493 __set_chan_timer(chan, chan->ops->get_sndtimeo(chan));
5494
5495 chan->ident = cmd->ident;
5496
5497 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) {
5498 l2cap_state_change(chan, BT_CONNECT2);
5499 /* The following result value is actually not defined
5500 * for LE CoC but we use it to let the function know
5501 * that it should bail out after doing its cleanup
5502 * instead of sending a response.
5503 */
5504 result = L2CAP_CR_PEND;
5505 chan->ops->defer(chan);
5506 } else {
5507 l2cap_chan_ready(chan);
5508 result = L2CAP_CR_SUCCESS;
5509 }
5510
5511response_unlock:
5512 l2cap_chan_unlock(pchan);
5513 mutex_unlock(&conn->chan_lock);
5514 l2cap_chan_put(pchan);
5515
5516 if (result == L2CAP_CR_PEND)
5517 return 0;
5518
5519response:
5520 if (chan) {
5521 rsp.mtu = cpu_to_le16(chan->imtu);
5522 rsp.mps = cpu_to_le16(chan->mps);
5523 } else {
5524 rsp.mtu = 0;
5525 rsp.mps = 0;
5526 }
5527
5528 rsp.dcid = cpu_to_le16(dcid);
5529 rsp.credits = cpu_to_le16(credits);
5530 rsp.result = cpu_to_le16(result);
5531
5532 l2cap_send_cmd(conn, cmd->ident, L2CAP_LE_CONN_RSP, sizeof(rsp), &rsp);
5533
5534 return 0;
5535}
5536
5537static inline int l2cap_le_credits(struct l2cap_conn *conn,
5538 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5539 u8 *data)
5540{
5541 struct l2cap_le_credits *pkt;
5542 struct l2cap_chan *chan;
5543 u16 cid, credits, max_credits;
5544
5545 if (cmd_len != sizeof(*pkt))
5546 return -EPROTO;
5547
5548 pkt = (struct l2cap_le_credits *) data;
5549 cid = __le16_to_cpu(pkt->cid);
5550 credits = __le16_to_cpu(pkt->credits);
5551
5552 BT_DBG("cid 0x%4.4x credits 0x%4.4x", cid, credits);
5553
5554 chan = l2cap_get_chan_by_dcid(conn, cid);
5555 if (!chan)
5556 return -EBADSLT;
5557
5558 max_credits = LE_FLOWCTL_MAX_CREDITS - chan->tx_credits;
5559 if (credits > max_credits) {
5560 BT_ERR("LE credits overflow");
5561 l2cap_send_disconn_req(chan, ECONNRESET);
5562 l2cap_chan_unlock(chan);
5563
5564 /* Return 0 so that we don't trigger an unnecessary
5565 * command reject packet.
5566 */
5567 return 0;
5568 }
5569
5570 chan->tx_credits += credits;
5571
5572 while (chan->tx_credits && !skb_queue_empty(&chan->tx_q)) {
5573 l2cap_do_send(chan, skb_dequeue(&chan->tx_q));
5574 chan->tx_credits--;
5575 }
5576
5577 if (chan->tx_credits)
5578 chan->ops->resume(chan);
5579
5580 l2cap_chan_unlock(chan);
5581
5582 return 0;
5583}
5584
5585static inline int l2cap_le_command_rej(struct l2cap_conn *conn,
5586 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5587 u8 *data)
5588{
5589 struct l2cap_cmd_rej_unk *rej = (struct l2cap_cmd_rej_unk *) data;
5590 struct l2cap_chan *chan;
5591
5592 if (cmd_len < sizeof(*rej))
5593 return -EPROTO;
5594
5595 mutex_lock(&conn->chan_lock);
5596
5597 chan = __l2cap_get_chan_by_ident(conn, cmd->ident);
5598 if (!chan)
5599 goto done;
5600
5601 l2cap_chan_lock(chan);
5602 l2cap_chan_del(chan, ECONNREFUSED);
5603 l2cap_chan_unlock(chan);
5604
5605done:
5606 mutex_unlock(&conn->chan_lock);
5607 return 0;
5608}
5609
5610static inline int l2cap_le_sig_cmd(struct l2cap_conn *conn,
5611 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5612 u8 *data)
5613{
5614 int err = 0;
5615
5616 switch (cmd->code) {
5617 case L2CAP_COMMAND_REJ:
5618 l2cap_le_command_rej(conn, cmd, cmd_len, data);
5619 break;
5620
5621 case L2CAP_CONN_PARAM_UPDATE_REQ:
5622 err = l2cap_conn_param_update_req(conn, cmd, cmd_len, data);
5623 break;
5624
5625 case L2CAP_CONN_PARAM_UPDATE_RSP:
5626 break;
5627
5628 case L2CAP_LE_CONN_RSP:
5629 l2cap_le_connect_rsp(conn, cmd, cmd_len, data);
5630 break;
5631
5632 case L2CAP_LE_CONN_REQ:
5633 err = l2cap_le_connect_req(conn, cmd, cmd_len, data);
5634 break;
5635
5636 case L2CAP_LE_CREDITS:
5637 err = l2cap_le_credits(conn, cmd, cmd_len, data);
5638 break;
5639
5640 case L2CAP_DISCONN_REQ:
5641 err = l2cap_disconnect_req(conn, cmd, cmd_len, data);
5642 break;
5643
5644 case L2CAP_DISCONN_RSP:
5645 l2cap_disconnect_rsp(conn, cmd, cmd_len, data);
5646 break;
5647
5648 default:
5649 BT_ERR("Unknown LE signaling command 0x%2.2x", cmd->code);
5650 err = -EINVAL;
5651 break;
5652 }
5653
5654 return err;
5655}
5656
5657static inline void l2cap_le_sig_channel(struct l2cap_conn *conn,
5658 struct sk_buff *skb)
5659{
5660 struct hci_conn *hcon = conn->hcon;
5661 struct l2cap_cmd_hdr *cmd;
5662 u16 len;
5663 int err;
5664
5665 if (hcon->type != LE_LINK)
5666 goto drop;
5667
5668 if (skb->len < L2CAP_CMD_HDR_SIZE)
5669 goto drop;
5670
5671 cmd = (void *) skb->data;
5672 skb_pull(skb, L2CAP_CMD_HDR_SIZE);
5673
5674 len = le16_to_cpu(cmd->len);
5675
5676 BT_DBG("code 0x%2.2x len %d id 0x%2.2x", cmd->code, len, cmd->ident);
5677
5678 if (len != skb->len || !cmd->ident) {
5679 BT_DBG("corrupted command");
5680 goto drop;
5681 }
5682
5683 err = l2cap_le_sig_cmd(conn, cmd, len, skb->data);
5684 if (err) {
5685 struct l2cap_cmd_rej_unk rej;
5686
5687 BT_ERR("Wrong link type (%d)", err);
5688
5689 rej.reason = cpu_to_le16(L2CAP_REJ_NOT_UNDERSTOOD);
5690 l2cap_send_cmd(conn, cmd->ident, L2CAP_COMMAND_REJ,
5691 sizeof(rej), &rej);
5692 }
5693
5694drop:
5695 kfree_skb(skb);
5696}
5697
5698static inline void l2cap_sig_channel(struct l2cap_conn *conn,
5699 struct sk_buff *skb)
5700{
5701 struct hci_conn *hcon = conn->hcon;
5702 u8 *data = skb->data;
5703 int len = skb->len;
5704 struct l2cap_cmd_hdr cmd;
5705 int err;
5706
5707 l2cap_raw_recv(conn, skb);
5708
5709 if (hcon->type != ACL_LINK)
5710 goto drop;
5711
5712 while (len >= L2CAP_CMD_HDR_SIZE) {
5713 u16 cmd_len;
5714 memcpy(&cmd, data, L2CAP_CMD_HDR_SIZE);
5715 data += L2CAP_CMD_HDR_SIZE;
5716 len -= L2CAP_CMD_HDR_SIZE;
5717
5718 cmd_len = le16_to_cpu(cmd.len);
5719
5720 BT_DBG("code 0x%2.2x len %d id 0x%2.2x", cmd.code, cmd_len,
5721 cmd.ident);
5722
5723 if (cmd_len > len || !cmd.ident) {
5724 BT_DBG("corrupted command");
5725 break;
5726 }
5727
5728 err = l2cap_bredr_sig_cmd(conn, &cmd, cmd_len, data);
5729 if (err) {
5730 struct l2cap_cmd_rej_unk rej;
5731
5732 BT_ERR("Wrong link type (%d)", err);
5733
5734 rej.reason = cpu_to_le16(L2CAP_REJ_NOT_UNDERSTOOD);
5735 l2cap_send_cmd(conn, cmd.ident, L2CAP_COMMAND_REJ,
5736 sizeof(rej), &rej);
5737 }
5738
5739 data += cmd_len;
5740 len -= cmd_len;
5741 }
5742
5743drop:
5744 kfree_skb(skb);
5745}
5746
5747static int l2cap_check_fcs(struct l2cap_chan *chan, struct sk_buff *skb)
5748{
5749 u16 our_fcs, rcv_fcs;
5750 int hdr_size;
5751
5752 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
5753 hdr_size = L2CAP_EXT_HDR_SIZE;
5754 else
5755 hdr_size = L2CAP_ENH_HDR_SIZE;
5756
5757 if (chan->fcs == L2CAP_FCS_CRC16) {
5758 skb_trim(skb, skb->len - L2CAP_FCS_SIZE);
5759 rcv_fcs = get_unaligned_le16(skb->data + skb->len);
5760 our_fcs = crc16(0, skb->data - hdr_size, skb->len + hdr_size);
5761
5762 if (our_fcs != rcv_fcs)
5763 return -EBADMSG;
5764 }
5765 return 0;
5766}
5767
5768static void l2cap_send_i_or_rr_or_rnr(struct l2cap_chan *chan)
5769{
5770 struct l2cap_ctrl control;
5771
5772 BT_DBG("chan %p", chan);
5773
5774 memset(&control, 0, sizeof(control));
5775 control.sframe = 1;
5776 control.final = 1;
5777 control.reqseq = chan->buffer_seq;
5778 set_bit(CONN_SEND_FBIT, &chan->conn_state);
5779
5780 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
5781 control.super = L2CAP_SUPER_RNR;
5782 l2cap_send_sframe(chan, &control);
5783 }
5784
5785 if (test_and_clear_bit(CONN_REMOTE_BUSY, &chan->conn_state) &&
5786 chan->unacked_frames > 0)
5787 __set_retrans_timer(chan);
5788
5789 /* Send pending iframes */
5790 l2cap_ertm_send(chan);
5791
5792 if (!test_bit(CONN_LOCAL_BUSY, &chan->conn_state) &&
5793 test_bit(CONN_SEND_FBIT, &chan->conn_state)) {
5794 /* F-bit wasn't sent in an s-frame or i-frame yet, so
5795 * send it now.
5796 */
5797 control.super = L2CAP_SUPER_RR;
5798 l2cap_send_sframe(chan, &control);
5799 }
5800}
5801
5802static void append_skb_frag(struct sk_buff *skb, struct sk_buff *new_frag,
5803 struct sk_buff **last_frag)
5804{
5805 /* skb->len reflects data in skb as well as all fragments
5806 * skb->data_len reflects only data in fragments
5807 */
5808 if (!skb_has_frag_list(skb))
5809 skb_shinfo(skb)->frag_list = new_frag;
5810
5811 new_frag->next = NULL;
5812
5813 (*last_frag)->next = new_frag;
5814 *last_frag = new_frag;
5815
5816 skb->len += new_frag->len;
5817 skb->data_len += new_frag->len;
5818 skb->truesize += new_frag->truesize;
5819}
5820
5821static int l2cap_reassemble_sdu(struct l2cap_chan *chan, struct sk_buff *skb,
5822 struct l2cap_ctrl *control)
5823{
5824 int err = -EINVAL;
5825
5826 switch (control->sar) {
5827 case L2CAP_SAR_UNSEGMENTED:
5828 if (chan->sdu)
5829 break;
5830
5831 err = chan->ops->recv(chan, skb);
5832 break;
5833
5834 case L2CAP_SAR_START:
5835 if (chan->sdu)
5836 break;
5837
5838 chan->sdu_len = get_unaligned_le16(skb->data);
5839 skb_pull(skb, L2CAP_SDULEN_SIZE);
5840
5841 if (chan->sdu_len > chan->imtu) {
5842 err = -EMSGSIZE;
5843 break;
5844 }
5845
5846 if (skb->len >= chan->sdu_len)
5847 break;
5848
5849 chan->sdu = skb;
5850 chan->sdu_last_frag = skb;
5851
5852 skb = NULL;
5853 err = 0;
5854 break;
5855
5856 case L2CAP_SAR_CONTINUE:
5857 if (!chan->sdu)
5858 break;
5859
5860 append_skb_frag(chan->sdu, skb,
5861 &chan->sdu_last_frag);
5862 skb = NULL;
5863
5864 if (chan->sdu->len >= chan->sdu_len)
5865 break;
5866
5867 err = 0;
5868 break;
5869
5870 case L2CAP_SAR_END:
5871 if (!chan->sdu)
5872 break;
5873
5874 append_skb_frag(chan->sdu, skb,
5875 &chan->sdu_last_frag);
5876 skb = NULL;
5877
5878 if (chan->sdu->len != chan->sdu_len)
5879 break;
5880
5881 err = chan->ops->recv(chan, chan->sdu);
5882
5883 if (!err) {
5884 /* Reassembly complete */
5885 chan->sdu = NULL;
5886 chan->sdu_last_frag = NULL;
5887 chan->sdu_len = 0;
5888 }
5889 break;
5890 }
5891
5892 if (err) {
5893 kfree_skb(skb);
5894 kfree_skb(chan->sdu);
5895 chan->sdu = NULL;
5896 chan->sdu_last_frag = NULL;
5897 chan->sdu_len = 0;
5898 }
5899
5900 return err;
5901}
5902
5903static int l2cap_resegment(struct l2cap_chan *chan)
5904{
5905 /* Placeholder */
5906 return 0;
5907}
5908
5909void l2cap_chan_busy(struct l2cap_chan *chan, int busy)
5910{
5911 u8 event;
5912
5913 if (chan->mode != L2CAP_MODE_ERTM)
5914 return;
5915
5916 event = busy ? L2CAP_EV_LOCAL_BUSY_DETECTED : L2CAP_EV_LOCAL_BUSY_CLEAR;
5917 l2cap_tx(chan, NULL, NULL, event);
5918}
5919
5920static int l2cap_rx_queued_iframes(struct l2cap_chan *chan)
5921{
5922 int err = 0;
5923 /* Pass sequential frames to l2cap_reassemble_sdu()
5924 * until a gap is encountered.
5925 */
5926
5927 BT_DBG("chan %p", chan);
5928
5929 while (!test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
5930 struct sk_buff *skb;
5931 BT_DBG("Searching for skb with txseq %d (queue len %d)",
5932 chan->buffer_seq, skb_queue_len(&chan->srej_q));
5933
5934 skb = l2cap_ertm_seq_in_queue(&chan->srej_q, chan->buffer_seq);
5935
5936 if (!skb)
5937 break;
5938
5939 skb_unlink(skb, &chan->srej_q);
5940 chan->buffer_seq = __next_seq(chan, chan->buffer_seq);
5941 err = l2cap_reassemble_sdu(chan, skb, &bt_cb(skb)->l2cap);
5942 if (err)
5943 break;
5944 }
5945
5946 if (skb_queue_empty(&chan->srej_q)) {
5947 chan->rx_state = L2CAP_RX_STATE_RECV;
5948 l2cap_send_ack(chan);
5949 }
5950
5951 return err;
5952}
5953
5954static void l2cap_handle_srej(struct l2cap_chan *chan,
5955 struct l2cap_ctrl *control)
5956{
5957 struct sk_buff *skb;
5958
5959 BT_DBG("chan %p, control %p", chan, control);
5960
5961 if (control->reqseq == chan->next_tx_seq) {
5962 BT_DBG("Invalid reqseq %d, disconnecting", control->reqseq);
5963 l2cap_send_disconn_req(chan, ECONNRESET);
5964 return;
5965 }
5966
5967 skb = l2cap_ertm_seq_in_queue(&chan->tx_q, control->reqseq);
5968
5969 if (skb == NULL) {
5970 BT_DBG("Seq %d not available for retransmission",
5971 control->reqseq);
5972 return;
5973 }
5974
5975 if (chan->max_tx != 0 && bt_cb(skb)->l2cap.retries >= chan->max_tx) {
5976 BT_DBG("Retry limit exceeded (%d)", chan->max_tx);
5977 l2cap_send_disconn_req(chan, ECONNRESET);
5978 return;
5979 }
5980
5981 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
5982
5983 if (control->poll) {
5984 l2cap_pass_to_tx(chan, control);
5985
5986 set_bit(CONN_SEND_FBIT, &chan->conn_state);
5987 l2cap_retransmit(chan, control);
5988 l2cap_ertm_send(chan);
5989
5990 if (chan->tx_state == L2CAP_TX_STATE_WAIT_F) {
5991 set_bit(CONN_SREJ_ACT, &chan->conn_state);
5992 chan->srej_save_reqseq = control->reqseq;
5993 }
5994 } else {
5995 l2cap_pass_to_tx_fbit(chan, control);
5996
5997 if (control->final) {
5998 if (chan->srej_save_reqseq != control->reqseq ||
5999 !test_and_clear_bit(CONN_SREJ_ACT,
6000 &chan->conn_state))
6001 l2cap_retransmit(chan, control);
6002 } else {
6003 l2cap_retransmit(chan, control);
6004 if (chan->tx_state == L2CAP_TX_STATE_WAIT_F) {
6005 set_bit(CONN_SREJ_ACT, &chan->conn_state);
6006 chan->srej_save_reqseq = control->reqseq;
6007 }
6008 }
6009 }
6010}
6011
6012static void l2cap_handle_rej(struct l2cap_chan *chan,
6013 struct l2cap_ctrl *control)
6014{
6015 struct sk_buff *skb;
6016
6017 BT_DBG("chan %p, control %p", chan, control);
6018
6019 if (control->reqseq == chan->next_tx_seq) {
6020 BT_DBG("Invalid reqseq %d, disconnecting", control->reqseq);
6021 l2cap_send_disconn_req(chan, ECONNRESET);
6022 return;
6023 }
6024
6025 skb = l2cap_ertm_seq_in_queue(&chan->tx_q, control->reqseq);
6026
6027 if (chan->max_tx && skb &&
6028 bt_cb(skb)->l2cap.retries >= chan->max_tx) {
6029 BT_DBG("Retry limit exceeded (%d)", chan->max_tx);
6030 l2cap_send_disconn_req(chan, ECONNRESET);
6031 return;
6032 }
6033
6034 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6035
6036 l2cap_pass_to_tx(chan, control);
6037
6038 if (control->final) {
6039 if (!test_and_clear_bit(CONN_REJ_ACT, &chan->conn_state))
6040 l2cap_retransmit_all(chan, control);
6041 } else {
6042 l2cap_retransmit_all(chan, control);
6043 l2cap_ertm_send(chan);
6044 if (chan->tx_state == L2CAP_TX_STATE_WAIT_F)
6045 set_bit(CONN_REJ_ACT, &chan->conn_state);
6046 }
6047}
6048
6049static u8 l2cap_classify_txseq(struct l2cap_chan *chan, u16 txseq)
6050{
6051 BT_DBG("chan %p, txseq %d", chan, txseq);
6052
6053 BT_DBG("last_acked_seq %d, expected_tx_seq %d", chan->last_acked_seq,
6054 chan->expected_tx_seq);
6055
6056 if (chan->rx_state == L2CAP_RX_STATE_SREJ_SENT) {
6057 if (__seq_offset(chan, txseq, chan->last_acked_seq) >=
6058 chan->tx_win) {
6059 /* See notes below regarding "double poll" and
6060 * invalid packets.
6061 */
6062 if (chan->tx_win <= ((chan->tx_win_max + 1) >> 1)) {
6063 BT_DBG("Invalid/Ignore - after SREJ");
6064 return L2CAP_TXSEQ_INVALID_IGNORE;
6065 } else {
6066 BT_DBG("Invalid - in window after SREJ sent");
6067 return L2CAP_TXSEQ_INVALID;
6068 }
6069 }
6070
6071 if (chan->srej_list.head == txseq) {
6072 BT_DBG("Expected SREJ");
6073 return L2CAP_TXSEQ_EXPECTED_SREJ;
6074 }
6075
6076 if (l2cap_ertm_seq_in_queue(&chan->srej_q, txseq)) {
6077 BT_DBG("Duplicate SREJ - txseq already stored");
6078 return L2CAP_TXSEQ_DUPLICATE_SREJ;
6079 }
6080
6081 if (l2cap_seq_list_contains(&chan->srej_list, txseq)) {
6082 BT_DBG("Unexpected SREJ - not requested");
6083 return L2CAP_TXSEQ_UNEXPECTED_SREJ;
6084 }
6085 }
6086
6087 if (chan->expected_tx_seq == txseq) {
6088 if (__seq_offset(chan, txseq, chan->last_acked_seq) >=
6089 chan->tx_win) {
6090 BT_DBG("Invalid - txseq outside tx window");
6091 return L2CAP_TXSEQ_INVALID;
6092 } else {
6093 BT_DBG("Expected");
6094 return L2CAP_TXSEQ_EXPECTED;
6095 }
6096 }
6097
6098 if (__seq_offset(chan, txseq, chan->last_acked_seq) <
6099 __seq_offset(chan, chan->expected_tx_seq, chan->last_acked_seq)) {
6100 BT_DBG("Duplicate - expected_tx_seq later than txseq");
6101 return L2CAP_TXSEQ_DUPLICATE;
6102 }
6103
6104 if (__seq_offset(chan, txseq, chan->last_acked_seq) >= chan->tx_win) {
6105 /* A source of invalid packets is a "double poll" condition,
6106 * where delays cause us to send multiple poll packets. If
6107 * the remote stack receives and processes both polls,
6108 * sequence numbers can wrap around in such a way that a
6109 * resent frame has a sequence number that looks like new data
6110 * with a sequence gap. This would trigger an erroneous SREJ
6111 * request.
6112 *
6113 * Fortunately, this is impossible with a tx window that's
6114 * less than half of the maximum sequence number, which allows
6115 * invalid frames to be safely ignored.
6116 *
6117 * With tx window sizes greater than half of the tx window
6118 * maximum, the frame is invalid and cannot be ignored. This
6119 * causes a disconnect.
6120 */
6121
6122 if (chan->tx_win <= ((chan->tx_win_max + 1) >> 1)) {
6123 BT_DBG("Invalid/Ignore - txseq outside tx window");
6124 return L2CAP_TXSEQ_INVALID_IGNORE;
6125 } else {
6126 BT_DBG("Invalid - txseq outside tx window");
6127 return L2CAP_TXSEQ_INVALID;
6128 }
6129 } else {
6130 BT_DBG("Unexpected - txseq indicates missing frames");
6131 return L2CAP_TXSEQ_UNEXPECTED;
6132 }
6133}
6134
6135static int l2cap_rx_state_recv(struct l2cap_chan *chan,
6136 struct l2cap_ctrl *control,
6137 struct sk_buff *skb, u8 event)
6138{
6139 int err = 0;
6140 bool skb_in_use = false;
6141
6142 BT_DBG("chan %p, control %p, skb %p, event %d", chan, control, skb,
6143 event);
6144
6145 switch (event) {
6146 case L2CAP_EV_RECV_IFRAME:
6147 switch (l2cap_classify_txseq(chan, control->txseq)) {
6148 case L2CAP_TXSEQ_EXPECTED:
6149 l2cap_pass_to_tx(chan, control);
6150
6151 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
6152 BT_DBG("Busy, discarding expected seq %d",
6153 control->txseq);
6154 break;
6155 }
6156
6157 chan->expected_tx_seq = __next_seq(chan,
6158 control->txseq);
6159
6160 chan->buffer_seq = chan->expected_tx_seq;
6161 skb_in_use = true;
6162
6163 err = l2cap_reassemble_sdu(chan, skb, control);
6164 if (err)
6165 break;
6166
6167 if (control->final) {
6168 if (!test_and_clear_bit(CONN_REJ_ACT,
6169 &chan->conn_state)) {
6170 control->final = 0;
6171 l2cap_retransmit_all(chan, control);
6172 l2cap_ertm_send(chan);
6173 }
6174 }
6175
6176 if (!test_bit(CONN_LOCAL_BUSY, &chan->conn_state))
6177 l2cap_send_ack(chan);
6178 break;
6179 case L2CAP_TXSEQ_UNEXPECTED:
6180 l2cap_pass_to_tx(chan, control);
6181
6182 /* Can't issue SREJ frames in the local busy state.
6183 * Drop this frame, it will be seen as missing
6184 * when local busy is exited.
6185 */
6186 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
6187 BT_DBG("Busy, discarding unexpected seq %d",
6188 control->txseq);
6189 break;
6190 }
6191
6192 /* There was a gap in the sequence, so an SREJ
6193 * must be sent for each missing frame. The
6194 * current frame is stored for later use.
6195 */
6196 skb_queue_tail(&chan->srej_q, skb);
6197 skb_in_use = true;
6198 BT_DBG("Queued %p (queue len %d)", skb,
6199 skb_queue_len(&chan->srej_q));
6200
6201 clear_bit(CONN_SREJ_ACT, &chan->conn_state);
6202 l2cap_seq_list_clear(&chan->srej_list);
6203 l2cap_send_srej(chan, control->txseq);
6204
6205 chan->rx_state = L2CAP_RX_STATE_SREJ_SENT;
6206 break;
6207 case L2CAP_TXSEQ_DUPLICATE:
6208 l2cap_pass_to_tx(chan, control);
6209 break;
6210 case L2CAP_TXSEQ_INVALID_IGNORE:
6211 break;
6212 case L2CAP_TXSEQ_INVALID:
6213 default:
6214 l2cap_send_disconn_req(chan, ECONNRESET);
6215 break;
6216 }
6217 break;
6218 case L2CAP_EV_RECV_RR:
6219 l2cap_pass_to_tx(chan, control);
6220 if (control->final) {
6221 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6222
6223 if (!test_and_clear_bit(CONN_REJ_ACT, &chan->conn_state) &&
6224 !__chan_is_moving(chan)) {
6225 control->final = 0;
6226 l2cap_retransmit_all(chan, control);
6227 }
6228
6229 l2cap_ertm_send(chan);
6230 } else if (control->poll) {
6231 l2cap_send_i_or_rr_or_rnr(chan);
6232 } else {
6233 if (test_and_clear_bit(CONN_REMOTE_BUSY,
6234 &chan->conn_state) &&
6235 chan->unacked_frames)
6236 __set_retrans_timer(chan);
6237
6238 l2cap_ertm_send(chan);
6239 }
6240 break;
6241 case L2CAP_EV_RECV_RNR:
6242 set_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6243 l2cap_pass_to_tx(chan, control);
6244 if (control && control->poll) {
6245 set_bit(CONN_SEND_FBIT, &chan->conn_state);
6246 l2cap_send_rr_or_rnr(chan, 0);
6247 }
6248 __clear_retrans_timer(chan);
6249 l2cap_seq_list_clear(&chan->retrans_list);
6250 break;
6251 case L2CAP_EV_RECV_REJ:
6252 l2cap_handle_rej(chan, control);
6253 break;
6254 case L2CAP_EV_RECV_SREJ:
6255 l2cap_handle_srej(chan, control);
6256 break;
6257 default:
6258 break;
6259 }
6260
6261 if (skb && !skb_in_use) {
6262 BT_DBG("Freeing %p", skb);
6263 kfree_skb(skb);
6264 }
6265
6266 return err;
6267}
6268
6269static int l2cap_rx_state_srej_sent(struct l2cap_chan *chan,
6270 struct l2cap_ctrl *control,
6271 struct sk_buff *skb, u8 event)
6272{
6273 int err = 0;
6274 u16 txseq = control->txseq;
6275 bool skb_in_use = false;
6276
6277 BT_DBG("chan %p, control %p, skb %p, event %d", chan, control, skb,
6278 event);
6279
6280 switch (event) {
6281 case L2CAP_EV_RECV_IFRAME:
6282 switch (l2cap_classify_txseq(chan, txseq)) {
6283 case L2CAP_TXSEQ_EXPECTED:
6284 /* Keep frame for reassembly later */
6285 l2cap_pass_to_tx(chan, control);
6286 skb_queue_tail(&chan->srej_q, skb);
6287 skb_in_use = true;
6288 BT_DBG("Queued %p (queue len %d)", skb,
6289 skb_queue_len(&chan->srej_q));
6290
6291 chan->expected_tx_seq = __next_seq(chan, txseq);
6292 break;
6293 case L2CAP_TXSEQ_EXPECTED_SREJ:
6294 l2cap_seq_list_pop(&chan->srej_list);
6295
6296 l2cap_pass_to_tx(chan, control);
6297 skb_queue_tail(&chan->srej_q, skb);
6298 skb_in_use = true;
6299 BT_DBG("Queued %p (queue len %d)", skb,
6300 skb_queue_len(&chan->srej_q));
6301
6302 err = l2cap_rx_queued_iframes(chan);
6303 if (err)
6304 break;
6305
6306 break;
6307 case L2CAP_TXSEQ_UNEXPECTED:
6308 /* Got a frame that can't be reassembled yet.
6309 * Save it for later, and send SREJs to cover
6310 * the missing frames.
6311 */
6312 skb_queue_tail(&chan->srej_q, skb);
6313 skb_in_use = true;
6314 BT_DBG("Queued %p (queue len %d)", skb,
6315 skb_queue_len(&chan->srej_q));
6316
6317 l2cap_pass_to_tx(chan, control);
6318 l2cap_send_srej(chan, control->txseq);
6319 break;
6320 case L2CAP_TXSEQ_UNEXPECTED_SREJ:
6321 /* This frame was requested with an SREJ, but
6322 * some expected retransmitted frames are
6323 * missing. Request retransmission of missing
6324 * SREJ'd frames.
6325 */
6326 skb_queue_tail(&chan->srej_q, skb);
6327 skb_in_use = true;
6328 BT_DBG("Queued %p (queue len %d)", skb,
6329 skb_queue_len(&chan->srej_q));
6330
6331 l2cap_pass_to_tx(chan, control);
6332 l2cap_send_srej_list(chan, control->txseq);
6333 break;
6334 case L2CAP_TXSEQ_DUPLICATE_SREJ:
6335 /* We've already queued this frame. Drop this copy. */
6336 l2cap_pass_to_tx(chan, control);
6337 break;
6338 case L2CAP_TXSEQ_DUPLICATE:
6339 /* Expecting a later sequence number, so this frame
6340 * was already received. Ignore it completely.
6341 */
6342 break;
6343 case L2CAP_TXSEQ_INVALID_IGNORE:
6344 break;
6345 case L2CAP_TXSEQ_INVALID:
6346 default:
6347 l2cap_send_disconn_req(chan, ECONNRESET);
6348 break;
6349 }
6350 break;
6351 case L2CAP_EV_RECV_RR:
6352 l2cap_pass_to_tx(chan, control);
6353 if (control->final) {
6354 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6355
6356 if (!test_and_clear_bit(CONN_REJ_ACT,
6357 &chan->conn_state)) {
6358 control->final = 0;
6359 l2cap_retransmit_all(chan, control);
6360 }
6361
6362 l2cap_ertm_send(chan);
6363 } else if (control->poll) {
6364 if (test_and_clear_bit(CONN_REMOTE_BUSY,
6365 &chan->conn_state) &&
6366 chan->unacked_frames) {
6367 __set_retrans_timer(chan);
6368 }
6369
6370 set_bit(CONN_SEND_FBIT, &chan->conn_state);
6371 l2cap_send_srej_tail(chan);
6372 } else {
6373 if (test_and_clear_bit(CONN_REMOTE_BUSY,
6374 &chan->conn_state) &&
6375 chan->unacked_frames)
6376 __set_retrans_timer(chan);
6377
6378 l2cap_send_ack(chan);
6379 }
6380 break;
6381 case L2CAP_EV_RECV_RNR:
6382 set_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6383 l2cap_pass_to_tx(chan, control);
6384 if (control->poll) {
6385 l2cap_send_srej_tail(chan);
6386 } else {
6387 struct l2cap_ctrl rr_control;
6388 memset(&rr_control, 0, sizeof(rr_control));
6389 rr_control.sframe = 1;
6390 rr_control.super = L2CAP_SUPER_RR;
6391 rr_control.reqseq = chan->buffer_seq;
6392 l2cap_send_sframe(chan, &rr_control);
6393 }
6394
6395 break;
6396 case L2CAP_EV_RECV_REJ:
6397 l2cap_handle_rej(chan, control);
6398 break;
6399 case L2CAP_EV_RECV_SREJ:
6400 l2cap_handle_srej(chan, control);
6401 break;
6402 }
6403
6404 if (skb && !skb_in_use) {
6405 BT_DBG("Freeing %p", skb);
6406 kfree_skb(skb);
6407 }
6408
6409 return err;
6410}
6411
6412static int l2cap_finish_move(struct l2cap_chan *chan)
6413{
6414 BT_DBG("chan %p", chan);
6415
6416 chan->rx_state = L2CAP_RX_STATE_RECV;
6417
6418 if (chan->hs_hcon)
6419 chan->conn->mtu = chan->hs_hcon->hdev->block_mtu;
6420 else
6421 chan->conn->mtu = chan->conn->hcon->hdev->acl_mtu;
6422
6423 return l2cap_resegment(chan);
6424}
6425
6426static int l2cap_rx_state_wait_p(struct l2cap_chan *chan,
6427 struct l2cap_ctrl *control,
6428 struct sk_buff *skb, u8 event)
6429{
6430 int err;
6431
6432 BT_DBG("chan %p, control %p, skb %p, event %d", chan, control, skb,
6433 event);
6434
6435 if (!control->poll)
6436 return -EPROTO;
6437
6438 l2cap_process_reqseq(chan, control->reqseq);
6439
6440 if (!skb_queue_empty(&chan->tx_q))
6441 chan->tx_send_head = skb_peek(&chan->tx_q);
6442 else
6443 chan->tx_send_head = NULL;
6444
6445 /* Rewind next_tx_seq to the point expected
6446 * by the receiver.
6447 */
6448 chan->next_tx_seq = control->reqseq;
6449 chan->unacked_frames = 0;
6450
6451 err = l2cap_finish_move(chan);
6452 if (err)
6453 return err;
6454
6455 set_bit(CONN_SEND_FBIT, &chan->conn_state);
6456 l2cap_send_i_or_rr_or_rnr(chan);
6457
6458 if (event == L2CAP_EV_RECV_IFRAME)
6459 return -EPROTO;
6460
6461 return l2cap_rx_state_recv(chan, control, NULL, event);
6462}
6463
6464static int l2cap_rx_state_wait_f(struct l2cap_chan *chan,
6465 struct l2cap_ctrl *control,
6466 struct sk_buff *skb, u8 event)
6467{
6468 int err;
6469
6470 if (!control->final)
6471 return -EPROTO;
6472
6473 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6474
6475 chan->rx_state = L2CAP_RX_STATE_RECV;
6476 l2cap_process_reqseq(chan, control->reqseq);
6477
6478 if (!skb_queue_empty(&chan->tx_q))
6479 chan->tx_send_head = skb_peek(&chan->tx_q);
6480 else
6481 chan->tx_send_head = NULL;
6482
6483 /* Rewind next_tx_seq to the point expected
6484 * by the receiver.
6485 */
6486 chan->next_tx_seq = control->reqseq;
6487 chan->unacked_frames = 0;
6488
6489 if (chan->hs_hcon)
6490 chan->conn->mtu = chan->hs_hcon->hdev->block_mtu;
6491 else
6492 chan->conn->mtu = chan->conn->hcon->hdev->acl_mtu;
6493
6494 err = l2cap_resegment(chan);
6495
6496 if (!err)
6497 err = l2cap_rx_state_recv(chan, control, skb, event);
6498
6499 return err;
6500}
6501
6502static bool __valid_reqseq(struct l2cap_chan *chan, u16 reqseq)
6503{
6504 /* Make sure reqseq is for a packet that has been sent but not acked */
6505 u16 unacked;
6506
6507 unacked = __seq_offset(chan, chan->next_tx_seq, chan->expected_ack_seq);
6508 return __seq_offset(chan, chan->next_tx_seq, reqseq) <= unacked;
6509}
6510
6511static int l2cap_rx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
6512 struct sk_buff *skb, u8 event)
6513{
6514 int err = 0;
6515
6516 BT_DBG("chan %p, control %p, skb %p, event %d, state %d", chan,
6517 control, skb, event, chan->rx_state);
6518
6519 if (__valid_reqseq(chan, control->reqseq)) {
6520 switch (chan->rx_state) {
6521 case L2CAP_RX_STATE_RECV:
6522 err = l2cap_rx_state_recv(chan, control, skb, event);
6523 break;
6524 case L2CAP_RX_STATE_SREJ_SENT:
6525 err = l2cap_rx_state_srej_sent(chan, control, skb,
6526 event);
6527 break;
6528 case L2CAP_RX_STATE_WAIT_P:
6529 err = l2cap_rx_state_wait_p(chan, control, skb, event);
6530 break;
6531 case L2CAP_RX_STATE_WAIT_F:
6532 err = l2cap_rx_state_wait_f(chan, control, skb, event);
6533 break;
6534 default:
6535 /* shut it down */
6536 break;
6537 }
6538 } else {
6539 BT_DBG("Invalid reqseq %d (next_tx_seq %d, expected_ack_seq %d",
6540 control->reqseq, chan->next_tx_seq,
6541 chan->expected_ack_seq);
6542 l2cap_send_disconn_req(chan, ECONNRESET);
6543 }
6544
6545 return err;
6546}
6547
6548static int l2cap_stream_rx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
6549 struct sk_buff *skb)
6550{
6551 BT_DBG("chan %p, control %p, skb %p, state %d", chan, control, skb,
6552 chan->rx_state);
6553
6554 if (l2cap_classify_txseq(chan, control->txseq) ==
6555 L2CAP_TXSEQ_EXPECTED) {
6556 l2cap_pass_to_tx(chan, control);
6557
6558 BT_DBG("buffer_seq %d->%d", chan->buffer_seq,
6559 __next_seq(chan, chan->buffer_seq));
6560
6561 chan->buffer_seq = __next_seq(chan, chan->buffer_seq);
6562
6563 l2cap_reassemble_sdu(chan, skb, control);
6564 } else {
6565 if (chan->sdu) {
6566 kfree_skb(chan->sdu);
6567 chan->sdu = NULL;
6568 }
6569 chan->sdu_last_frag = NULL;
6570 chan->sdu_len = 0;
6571
6572 if (skb) {
6573 BT_DBG("Freeing %p", skb);
6574 kfree_skb(skb);
6575 }
6576 }
6577
6578 chan->last_acked_seq = control->txseq;
6579 chan->expected_tx_seq = __next_seq(chan, control->txseq);
6580
6581 return 0;
6582}
6583
6584static int l2cap_data_rcv(struct l2cap_chan *chan, struct sk_buff *skb)
6585{
6586 struct l2cap_ctrl *control = &bt_cb(skb)->l2cap;
6587 u16 len;
6588 u8 event;
6589
6590 __unpack_control(chan, skb);
6591
6592 len = skb->len;
6593
6594 /*
6595 * We can just drop the corrupted I-frame here.
6596 * Receiver will miss it and start proper recovery
6597 * procedures and ask for retransmission.
6598 */
6599 if (l2cap_check_fcs(chan, skb))
6600 goto drop;
6601
6602 if (!control->sframe && control->sar == L2CAP_SAR_START)
6603 len -= L2CAP_SDULEN_SIZE;
6604
6605 if (chan->fcs == L2CAP_FCS_CRC16)
6606 len -= L2CAP_FCS_SIZE;
6607
6608 if (len > chan->mps) {
6609 l2cap_send_disconn_req(chan, ECONNRESET);
6610 goto drop;
6611 }
6612
6613 if (!control->sframe) {
6614 int err;
6615
6616 BT_DBG("iframe sar %d, reqseq %d, final %d, txseq %d",
6617 control->sar, control->reqseq, control->final,
6618 control->txseq);
6619
6620 /* Validate F-bit - F=0 always valid, F=1 only
6621 * valid in TX WAIT_F
6622 */
6623 if (control->final && chan->tx_state != L2CAP_TX_STATE_WAIT_F)
6624 goto drop;
6625
6626 if (chan->mode != L2CAP_MODE_STREAMING) {
6627 event = L2CAP_EV_RECV_IFRAME;
6628 err = l2cap_rx(chan, control, skb, event);
6629 } else {
6630 err = l2cap_stream_rx(chan, control, skb);
6631 }
6632
6633 if (err)
6634 l2cap_send_disconn_req(chan, ECONNRESET);
6635 } else {
6636 const u8 rx_func_to_event[4] = {
6637 L2CAP_EV_RECV_RR, L2CAP_EV_RECV_REJ,
6638 L2CAP_EV_RECV_RNR, L2CAP_EV_RECV_SREJ
6639 };
6640
6641 /* Only I-frames are expected in streaming mode */
6642 if (chan->mode == L2CAP_MODE_STREAMING)
6643 goto drop;
6644
6645 BT_DBG("sframe reqseq %d, final %d, poll %d, super %d",
6646 control->reqseq, control->final, control->poll,
6647 control->super);
6648
6649 if (len != 0) {
6650 BT_ERR("Trailing bytes: %d in sframe", len);
6651 l2cap_send_disconn_req(chan, ECONNRESET);
6652 goto drop;
6653 }
6654
6655 /* Validate F and P bits */
6656 if (control->final && (control->poll ||
6657 chan->tx_state != L2CAP_TX_STATE_WAIT_F))
6658 goto drop;
6659
6660 event = rx_func_to_event[control->super];
6661 if (l2cap_rx(chan, control, skb, event))
6662 l2cap_send_disconn_req(chan, ECONNRESET);
6663 }
6664
6665 return 0;
6666
6667drop:
6668 kfree_skb(skb);
6669 return 0;
6670}
6671
6672static void l2cap_chan_le_send_credits(struct l2cap_chan *chan)
6673{
6674 struct l2cap_conn *conn = chan->conn;
6675 struct l2cap_le_credits pkt;
6676 u16 return_credits;
6677
6678 /* We return more credits to the sender only after the amount of
6679 * credits falls below half of the initial amount.
6680 */
6681 if (chan->rx_credits >= (le_max_credits + 1) / 2)
6682 return;
6683
6684 return_credits = le_max_credits - chan->rx_credits;
6685
6686 BT_DBG("chan %p returning %u credits to sender", chan, return_credits);
6687
6688 chan->rx_credits += return_credits;
6689
6690 pkt.cid = cpu_to_le16(chan->scid);
6691 pkt.credits = cpu_to_le16(return_credits);
6692
6693 chan->ident = l2cap_get_ident(conn);
6694
6695 l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CREDITS, sizeof(pkt), &pkt);
6696}
6697
6698static int l2cap_le_data_rcv(struct l2cap_chan *chan, struct sk_buff *skb)
6699{
6700 int err;
6701
6702 if (!chan->rx_credits) {
6703 BT_ERR("No credits to receive LE L2CAP data");
6704 l2cap_send_disconn_req(chan, ECONNRESET);
6705 return -ENOBUFS;
6706 }
6707
6708 if (chan->imtu < skb->len) {
6709 BT_ERR("Too big LE L2CAP PDU");
6710 return -ENOBUFS;
6711 }
6712
6713 chan->rx_credits--;
6714 BT_DBG("rx_credits %u -> %u", chan->rx_credits + 1, chan->rx_credits);
6715
6716 l2cap_chan_le_send_credits(chan);
6717
6718 err = 0;
6719
6720 if (!chan->sdu) {
6721 u16 sdu_len;
6722
6723 sdu_len = get_unaligned_le16(skb->data);
6724 skb_pull(skb, L2CAP_SDULEN_SIZE);
6725
6726 BT_DBG("Start of new SDU. sdu_len %u skb->len %u imtu %u",
6727 sdu_len, skb->len, chan->imtu);
6728
6729 if (sdu_len > chan->imtu) {
6730 BT_ERR("Too big LE L2CAP SDU length received");
6731 err = -EMSGSIZE;
6732 goto failed;
6733 }
6734
6735 if (skb->len > sdu_len) {
6736 BT_ERR("Too much LE L2CAP data received");
6737 err = -EINVAL;
6738 goto failed;
6739 }
6740
6741 if (skb->len == sdu_len)
6742 return chan->ops->recv(chan, skb);
6743
6744 chan->sdu = skb;
6745 chan->sdu_len = sdu_len;
6746 chan->sdu_last_frag = skb;
6747
6748 return 0;
6749 }
6750
6751 BT_DBG("SDU fragment. chan->sdu->len %u skb->len %u chan->sdu_len %u",
6752 chan->sdu->len, skb->len, chan->sdu_len);
6753
6754 if (chan->sdu->len + skb->len > chan->sdu_len) {
6755 BT_ERR("Too much LE L2CAP data received");
6756 err = -EINVAL;
6757 goto failed;
6758 }
6759
6760 append_skb_frag(chan->sdu, skb, &chan->sdu_last_frag);
6761 skb = NULL;
6762
6763 if (chan->sdu->len == chan->sdu_len) {
6764 err = chan->ops->recv(chan, chan->sdu);
6765 if (!err) {
6766 chan->sdu = NULL;
6767 chan->sdu_last_frag = NULL;
6768 chan->sdu_len = 0;
6769 }
6770 }
6771
6772failed:
6773 if (err) {
6774 kfree_skb(skb);
6775 kfree_skb(chan->sdu);
6776 chan->sdu = NULL;
6777 chan->sdu_last_frag = NULL;
6778 chan->sdu_len = 0;
6779 }
6780
6781 /* We can't return an error here since we took care of the skb
6782 * freeing internally. An error return would cause the caller to
6783 * do a double-free of the skb.
6784 */
6785 return 0;
6786}
6787
6788static void l2cap_data_channel(struct l2cap_conn *conn, u16 cid,
6789 struct sk_buff *skb)
6790{
6791 struct l2cap_chan *chan;
6792
6793 chan = l2cap_get_chan_by_scid(conn, cid);
6794 if (!chan) {
6795 if (cid == L2CAP_CID_A2MP) {
6796 chan = a2mp_channel_create(conn, skb);
6797 if (!chan) {
6798 kfree_skb(skb);
6799 return;
6800 }
6801
6802 l2cap_chan_lock(chan);
6803 } else {
6804 BT_DBG("unknown cid 0x%4.4x", cid);
6805 /* Drop packet and return */
6806 kfree_skb(skb);
6807 return;
6808 }
6809 }
6810
6811 BT_DBG("chan %p, len %d", chan, skb->len);
6812
6813 /* If we receive data on a fixed channel before the info req/rsp
6814 * procdure is done simply assume that the channel is supported
6815 * and mark it as ready.
6816 */
6817 if (chan->chan_type == L2CAP_CHAN_FIXED)
6818 l2cap_chan_ready(chan);
6819
6820 if (chan->state != BT_CONNECTED)
6821 goto drop;
6822
6823 switch (chan->mode) {
6824 case L2CAP_MODE_LE_FLOWCTL:
6825 if (l2cap_le_data_rcv(chan, skb) < 0)
6826 goto drop;
6827
6828 goto done;
6829
6830 case L2CAP_MODE_BASIC:
6831 /* If socket recv buffers overflows we drop data here
6832 * which is *bad* because L2CAP has to be reliable.
6833 * But we don't have any other choice. L2CAP doesn't
6834 * provide flow control mechanism. */
6835
6836 if (chan->imtu < skb->len) {
6837 BT_ERR("Dropping L2CAP data: receive buffer overflow");
6838 goto drop;
6839 }
6840
6841 if (!chan->ops->recv(chan, skb))
6842 goto done;
6843 break;
6844
6845 case L2CAP_MODE_ERTM:
6846 case L2CAP_MODE_STREAMING:
6847 l2cap_data_rcv(chan, skb);
6848 goto done;
6849
6850 default:
6851 BT_DBG("chan %p: bad mode 0x%2.2x", chan, chan->mode);
6852 break;
6853 }
6854
6855drop:
6856 kfree_skb(skb);
6857
6858done:
6859 l2cap_chan_unlock(chan);
6860}
6861
6862static void l2cap_conless_channel(struct l2cap_conn *conn, __le16 psm,
6863 struct sk_buff *skb)
6864{
6865 struct hci_conn *hcon = conn->hcon;
6866 struct l2cap_chan *chan;
6867
6868 if (hcon->type != ACL_LINK)
6869 goto free_skb;
6870
6871 chan = l2cap_global_chan_by_psm(0, psm, &hcon->src, &hcon->dst,
6872 ACL_LINK);
6873 if (!chan)
6874 goto free_skb;
6875
6876 BT_DBG("chan %p, len %d", chan, skb->len);
6877
6878 if (chan->state != BT_BOUND && chan->state != BT_CONNECTED)
6879 goto drop;
6880
6881 if (chan->imtu < skb->len)
6882 goto drop;
6883
6884 /* Store remote BD_ADDR and PSM for msg_name */
6885 bacpy(&bt_cb(skb)->l2cap.bdaddr, &hcon->dst);
6886 bt_cb(skb)->l2cap.psm = psm;
6887
6888 if (!chan->ops->recv(chan, skb)) {
6889 l2cap_chan_put(chan);
6890 return;
6891 }
6892
6893drop:
6894 l2cap_chan_put(chan);
6895free_skb:
6896 kfree_skb(skb);
6897}
6898
6899static void l2cap_recv_frame(struct l2cap_conn *conn, struct sk_buff *skb)
6900{
6901 struct l2cap_hdr *lh = (void *) skb->data;
6902 struct hci_conn *hcon = conn->hcon;
6903 u16 cid, len;
6904 __le16 psm;
6905
6906 if (hcon->state != BT_CONNECTED) {
6907 BT_DBG("queueing pending rx skb");
6908 skb_queue_tail(&conn->pending_rx, skb);
6909 return;
6910 }
6911
6912 skb_pull(skb, L2CAP_HDR_SIZE);
6913 cid = __le16_to_cpu(lh->cid);
6914 len = __le16_to_cpu(lh->len);
6915
6916 if (len != skb->len) {
6917 kfree_skb(skb);
6918 return;
6919 }
6920
6921 /* Since we can't actively block incoming LE connections we must
6922 * at least ensure that we ignore incoming data from them.
6923 */
6924 if (hcon->type == LE_LINK &&
6925 hci_bdaddr_list_lookup(&hcon->hdev->blacklist, &hcon->dst,
6926 bdaddr_dst_type(hcon))) {
6927 kfree_skb(skb);
6928 return;
6929 }
6930
6931 BT_DBG("len %d, cid 0x%4.4x", len, cid);
6932
6933 switch (cid) {
6934 case L2CAP_CID_SIGNALING:
6935 l2cap_sig_channel(conn, skb);
6936 break;
6937
6938 case L2CAP_CID_CONN_LESS:
6939 psm = get_unaligned((__le16 *) skb->data);
6940 skb_pull(skb, L2CAP_PSMLEN_SIZE);
6941 l2cap_conless_channel(conn, psm, skb);
6942 break;
6943
6944 case L2CAP_CID_LE_SIGNALING:
6945 l2cap_le_sig_channel(conn, skb);
6946 break;
6947
6948 default:
6949 l2cap_data_channel(conn, cid, skb);
6950 break;
6951 }
6952}
6953
6954static void process_pending_rx(struct work_struct *work)
6955{
6956 struct l2cap_conn *conn = container_of(work, struct l2cap_conn,
6957 pending_rx_work);
6958 struct sk_buff *skb;
6959
6960 BT_DBG("");
6961
6962 while ((skb = skb_dequeue(&conn->pending_rx)))
6963 l2cap_recv_frame(conn, skb);
6964}
6965
6966static struct l2cap_conn *l2cap_conn_add(struct hci_conn *hcon)
6967{
6968 struct l2cap_conn *conn = hcon->l2cap_data;
6969 struct hci_chan *hchan;
6970
6971 if (conn)
6972 return conn;
6973
6974 hchan = hci_chan_create(hcon);
6975 if (!hchan)
6976 return NULL;
6977
6978 conn = kzalloc(sizeof(*conn), GFP_KERNEL);
6979 if (!conn) {
6980 hci_chan_del(hchan);
6981 return NULL;
6982 }
6983
6984 kref_init(&conn->ref);
6985 hcon->l2cap_data = conn;
6986 conn->hcon = hci_conn_get(hcon);
6987 conn->hchan = hchan;
6988
6989 BT_DBG("hcon %p conn %p hchan %p", hcon, conn, hchan);
6990
6991 switch (hcon->type) {
6992 case LE_LINK:
6993 if (hcon->hdev->le_mtu) {
6994 conn->mtu = hcon->hdev->le_mtu;
6995 break;
6996 }
6997 /* fall through */
6998 default:
6999 conn->mtu = hcon->hdev->acl_mtu;
7000 break;
7001 }
7002
7003 conn->feat_mask = 0;
7004
7005 conn->local_fixed_chan = L2CAP_FC_SIG_BREDR | L2CAP_FC_CONNLESS;
7006
7007 if (hcon->type == ACL_LINK &&
7008 hci_dev_test_flag(hcon->hdev, HCI_HS_ENABLED))
7009 conn->local_fixed_chan |= L2CAP_FC_A2MP;
7010
7011 if (hci_dev_test_flag(hcon->hdev, HCI_LE_ENABLED) &&
7012 (bredr_sc_enabled(hcon->hdev) ||
7013 hci_dev_test_flag(hcon->hdev, HCI_FORCE_BREDR_SMP)))
7014 conn->local_fixed_chan |= L2CAP_FC_SMP_BREDR;
7015
7016 mutex_init(&conn->ident_lock);
7017 mutex_init(&conn->chan_lock);
7018
7019 INIT_LIST_HEAD(&conn->chan_l);
7020 INIT_LIST_HEAD(&conn->users);
7021
7022 INIT_DELAYED_WORK(&conn->info_timer, l2cap_info_timeout);
7023
7024 skb_queue_head_init(&conn->pending_rx);
7025 INIT_WORK(&conn->pending_rx_work, process_pending_rx);
7026 INIT_WORK(&conn->id_addr_update_work, l2cap_conn_update_id_addr);
7027
7028 conn->disc_reason = HCI_ERROR_REMOTE_USER_TERM;
7029
7030 return conn;
7031}
7032
7033static bool is_valid_psm(u16 psm, u8 dst_type) {
7034 if (!psm)
7035 return false;
7036
7037 if (bdaddr_type_is_le(dst_type))
7038 return (psm <= 0x00ff);
7039
7040 /* PSM must be odd and lsb of upper byte must be 0 */
7041 return ((psm & 0x0101) == 0x0001);
7042}
7043
7044int l2cap_chan_connect(struct l2cap_chan *chan, __le16 psm, u16 cid,
7045 bdaddr_t *dst, u8 dst_type)
7046{
7047 struct l2cap_conn *conn;
7048 struct hci_conn *hcon;
7049 struct hci_dev *hdev;
7050 int err;
7051
7052 BT_DBG("%pMR -> %pMR (type %u) psm 0x%2.2x", &chan->src, dst,
7053 dst_type, __le16_to_cpu(psm));
7054
7055 hdev = hci_get_route(dst, &chan->src);
7056 if (!hdev)
7057 return -EHOSTUNREACH;
7058
7059 hci_dev_lock(hdev);
7060
7061 if (!is_valid_psm(__le16_to_cpu(psm), dst_type) && !cid &&
7062 chan->chan_type != L2CAP_CHAN_RAW) {
7063 err = -EINVAL;
7064 goto done;
7065 }
7066
7067 if (chan->chan_type == L2CAP_CHAN_CONN_ORIENTED && !psm) {
7068 err = -EINVAL;
7069 goto done;
7070 }
7071
7072 if (chan->chan_type == L2CAP_CHAN_FIXED && !cid) {
7073 err = -EINVAL;
7074 goto done;
7075 }
7076
7077 switch (chan->mode) {
7078 case L2CAP_MODE_BASIC:
7079 break;
7080 case L2CAP_MODE_LE_FLOWCTL:
7081 l2cap_le_flowctl_init(chan);
7082 break;
7083 case L2CAP_MODE_ERTM:
7084 case L2CAP_MODE_STREAMING:
7085 if (!disable_ertm)
7086 break;
7087 /* fall through */
7088 default:
7089 err = -EOPNOTSUPP;
7090 goto done;
7091 }
7092
7093 switch (chan->state) {
7094 case BT_CONNECT:
7095 case BT_CONNECT2:
7096 case BT_CONFIG:
7097 /* Already connecting */
7098 err = 0;
7099 goto done;
7100
7101 case BT_CONNECTED:
7102 /* Already connected */
7103 err = -EISCONN;
7104 goto done;
7105
7106 case BT_OPEN:
7107 case BT_BOUND:
7108 /* Can connect */
7109 break;
7110
7111 default:
7112 err = -EBADFD;
7113 goto done;
7114 }
7115
7116 /* Set destination address and psm */
7117 bacpy(&chan->dst, dst);
7118 chan->dst_type = dst_type;
7119
7120 chan->psm = psm;
7121 chan->dcid = cid;
7122
7123 if (bdaddr_type_is_le(dst_type)) {
7124 /* Convert from L2CAP channel address type to HCI address type
7125 */
7126 if (dst_type == BDADDR_LE_PUBLIC)
7127 dst_type = ADDR_LE_DEV_PUBLIC;
7128 else
7129 dst_type = ADDR_LE_DEV_RANDOM;
7130
7131 if (hci_dev_test_flag(hdev, HCI_ADVERTISING))
7132 hcon = hci_connect_le(hdev, dst, dst_type,
7133 chan->sec_level,
7134 HCI_LE_CONN_TIMEOUT,
7135 HCI_ROLE_SLAVE);
7136 else
7137 hcon = hci_connect_le_scan(hdev, dst, dst_type,
7138 chan->sec_level,
7139 HCI_LE_CONN_TIMEOUT);
7140
7141 } else {
7142 u8 auth_type = l2cap_get_auth_type(chan);
7143 hcon = hci_connect_acl(hdev, dst, chan->sec_level, auth_type);
7144 }
7145
7146 if (IS_ERR(hcon)) {
7147 err = PTR_ERR(hcon);
7148 goto done;
7149 }
7150
7151 conn = l2cap_conn_add(hcon);
7152 if (!conn) {
7153 hci_conn_drop(hcon);
7154 err = -ENOMEM;
7155 goto done;
7156 }
7157
7158 mutex_lock(&conn->chan_lock);
7159 l2cap_chan_lock(chan);
7160
7161 if (cid && __l2cap_get_chan_by_dcid(conn, cid)) {
7162 hci_conn_drop(hcon);
7163 err = -EBUSY;
7164 goto chan_unlock;
7165 }
7166
7167 /* Update source addr of the socket */
7168 bacpy(&chan->src, &hcon->src);
7169 chan->src_type = bdaddr_src_type(hcon);
7170
7171 __l2cap_chan_add(conn, chan);
7172
7173 /* l2cap_chan_add takes its own ref so we can drop this one */
7174 hci_conn_drop(hcon);
7175
7176 l2cap_state_change(chan, BT_CONNECT);
7177 __set_chan_timer(chan, chan->ops->get_sndtimeo(chan));
7178
7179 /* Release chan->sport so that it can be reused by other
7180 * sockets (as it's only used for listening sockets).
7181 */
7182 write_lock(&chan_list_lock);
7183 chan->sport = 0;
7184 write_unlock(&chan_list_lock);
7185
7186 if (hcon->state == BT_CONNECTED) {
7187 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) {
7188 __clear_chan_timer(chan);
7189 if (l2cap_chan_check_security(chan, true))
7190 l2cap_state_change(chan, BT_CONNECTED);
7191 } else
7192 l2cap_do_start(chan);
7193 }
7194
7195 err = 0;
7196
7197chan_unlock:
7198 l2cap_chan_unlock(chan);
7199 mutex_unlock(&conn->chan_lock);
7200done:
7201 hci_dev_unlock(hdev);
7202 hci_dev_put(hdev);
7203 return err;
7204}
7205EXPORT_SYMBOL_GPL(l2cap_chan_connect);
7206
7207/* ---- L2CAP interface with lower layer (HCI) ---- */
7208
7209int l2cap_connect_ind(struct hci_dev *hdev, bdaddr_t *bdaddr)
7210{
7211 int exact = 0, lm1 = 0, lm2 = 0;
7212 struct l2cap_chan *c;
7213
7214 BT_DBG("hdev %s, bdaddr %pMR", hdev->name, bdaddr);
7215
7216 /* Find listening sockets and check their link_mode */
7217 read_lock(&chan_list_lock);
7218 list_for_each_entry(c, &chan_list, global_l) {
7219 if (c->state != BT_LISTEN)
7220 continue;
7221
7222 if (!bacmp(&c->src, &hdev->bdaddr)) {
7223 lm1 |= HCI_LM_ACCEPT;
7224 if (test_bit(FLAG_ROLE_SWITCH, &c->flags))
7225 lm1 |= HCI_LM_MASTER;
7226 exact++;
7227 } else if (!bacmp(&c->src, BDADDR_ANY)) {
7228 lm2 |= HCI_LM_ACCEPT;
7229 if (test_bit(FLAG_ROLE_SWITCH, &c->flags))
7230 lm2 |= HCI_LM_MASTER;
7231 }
7232 }
7233 read_unlock(&chan_list_lock);
7234
7235 return exact ? lm1 : lm2;
7236}
7237
7238/* Find the next fixed channel in BT_LISTEN state, continue iteration
7239 * from an existing channel in the list or from the beginning of the
7240 * global list (by passing NULL as first parameter).
7241 */
7242static struct l2cap_chan *l2cap_global_fixed_chan(struct l2cap_chan *c,
7243 struct hci_conn *hcon)
7244{
7245 u8 src_type = bdaddr_src_type(hcon);
7246
7247 read_lock(&chan_list_lock);
7248
7249 if (c)
7250 c = list_next_entry(c, global_l);
7251 else
7252 c = list_entry(chan_list.next, typeof(*c), global_l);
7253
7254 list_for_each_entry_from(c, &chan_list, global_l) {
7255 if (c->chan_type != L2CAP_CHAN_FIXED)
7256 continue;
7257 if (c->state != BT_LISTEN)
7258 continue;
7259 if (bacmp(&c->src, &hcon->src) && bacmp(&c->src, BDADDR_ANY))
7260 continue;
7261 if (src_type != c->src_type)
7262 continue;
7263
7264 l2cap_chan_hold(c);
7265 read_unlock(&chan_list_lock);
7266 return c;
7267 }
7268
7269 read_unlock(&chan_list_lock);
7270
7271 return NULL;
7272}
7273
7274static void l2cap_connect_cfm(struct hci_conn *hcon, u8 status)
7275{
7276 struct hci_dev *hdev = hcon->hdev;
7277 struct l2cap_conn *conn;
7278 struct l2cap_chan *pchan;
7279 u8 dst_type;
7280
7281 if (hcon->type != ACL_LINK && hcon->type != LE_LINK)
7282 return;
7283
7284 BT_DBG("hcon %p bdaddr %pMR status %d", hcon, &hcon->dst, status);
7285
7286 if (status) {
7287 l2cap_conn_del(hcon, bt_to_errno(status));
7288 return;
7289 }
7290
7291 conn = l2cap_conn_add(hcon);
7292 if (!conn)
7293 return;
7294
7295 dst_type = bdaddr_dst_type(hcon);
7296
7297 /* If device is blocked, do not create channels for it */
7298 if (hci_bdaddr_list_lookup(&hdev->blacklist, &hcon->dst, dst_type))
7299 return;
7300
7301 /* Find fixed channels and notify them of the new connection. We
7302 * use multiple individual lookups, continuing each time where
7303 * we left off, because the list lock would prevent calling the
7304 * potentially sleeping l2cap_chan_lock() function.
7305 */
7306 pchan = l2cap_global_fixed_chan(NULL, hcon);
7307 while (pchan) {
7308 struct l2cap_chan *chan, *next;
7309
7310 /* Client fixed channels should override server ones */
7311 if (__l2cap_get_chan_by_dcid(conn, pchan->scid))
7312 goto next;
7313
7314 l2cap_chan_lock(pchan);
7315 chan = pchan->ops->new_connection(pchan);
7316 if (chan) {
7317 bacpy(&chan->src, &hcon->src);
7318 bacpy(&chan->dst, &hcon->dst);
7319 chan->src_type = bdaddr_src_type(hcon);
7320 chan->dst_type = dst_type;
7321
7322 __l2cap_chan_add(conn, chan);
7323 }
7324
7325 l2cap_chan_unlock(pchan);
7326next:
7327 next = l2cap_global_fixed_chan(pchan, hcon);
7328 l2cap_chan_put(pchan);
7329 pchan = next;
7330 }
7331
7332 l2cap_conn_ready(conn);
7333}
7334
7335int l2cap_disconn_ind(struct hci_conn *hcon)
7336{
7337 struct l2cap_conn *conn = hcon->l2cap_data;
7338
7339 BT_DBG("hcon %p", hcon);
7340
7341 if (!conn)
7342 return HCI_ERROR_REMOTE_USER_TERM;
7343 return conn->disc_reason;
7344}
7345
7346static void l2cap_disconn_cfm(struct hci_conn *hcon, u8 reason)
7347{
7348 if (hcon->type != ACL_LINK && hcon->type != LE_LINK)
7349 return;
7350
7351 BT_DBG("hcon %p reason %d", hcon, reason);
7352
7353 l2cap_conn_del(hcon, bt_to_errno(reason));
7354}
7355
7356static inline void l2cap_check_encryption(struct l2cap_chan *chan, u8 encrypt)
7357{
7358 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED)
7359 return;
7360
7361 if (encrypt == 0x00) {
7362 if (chan->sec_level == BT_SECURITY_MEDIUM) {
7363 __set_chan_timer(chan, L2CAP_ENC_TIMEOUT);
7364 } else if (chan->sec_level == BT_SECURITY_HIGH ||
7365 chan->sec_level == BT_SECURITY_FIPS)
7366 l2cap_chan_close(chan, ECONNREFUSED);
7367 } else {
7368 if (chan->sec_level == BT_SECURITY_MEDIUM)
7369 __clear_chan_timer(chan);
7370 }
7371}
7372
7373static void l2cap_security_cfm(struct hci_conn *hcon, u8 status, u8 encrypt)
7374{
7375 struct l2cap_conn *conn = hcon->l2cap_data;
7376 struct l2cap_chan *chan;
7377
7378 if (!conn)
7379 return;
7380
7381 BT_DBG("conn %p status 0x%2.2x encrypt %u", conn, status, encrypt);
7382
7383 mutex_lock(&conn->chan_lock);
7384
7385 list_for_each_entry(chan, &conn->chan_l, list) {
7386 l2cap_chan_lock(chan);
7387
7388 BT_DBG("chan %p scid 0x%4.4x state %s", chan, chan->scid,
7389 state_to_string(chan->state));
7390
7391 if (chan->scid == L2CAP_CID_A2MP) {
7392 l2cap_chan_unlock(chan);
7393 continue;
7394 }
7395
7396 if (!status && encrypt)
7397 chan->sec_level = hcon->sec_level;
7398
7399 if (!__l2cap_no_conn_pending(chan)) {
7400 l2cap_chan_unlock(chan);
7401 continue;
7402 }
7403
7404 if (!status && (chan->state == BT_CONNECTED ||
7405 chan->state == BT_CONFIG)) {
7406 chan->ops->resume(chan);
7407 l2cap_check_encryption(chan, encrypt);
7408 l2cap_chan_unlock(chan);
7409 continue;
7410 }
7411
7412 if (chan->state == BT_CONNECT) {
7413 if (!status)
7414 l2cap_start_connection(chan);
7415 else
7416 __set_chan_timer(chan, L2CAP_DISC_TIMEOUT);
7417 } else if (chan->state == BT_CONNECT2 &&
7418 chan->mode != L2CAP_MODE_LE_FLOWCTL) {
7419 struct l2cap_conn_rsp rsp;
7420 __u16 res, stat;
7421
7422 if (!status) {
7423 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) {
7424 res = L2CAP_CR_PEND;
7425 stat = L2CAP_CS_AUTHOR_PEND;
7426 chan->ops->defer(chan);
7427 } else {
7428 l2cap_state_change(chan, BT_CONFIG);
7429 res = L2CAP_CR_SUCCESS;
7430 stat = L2CAP_CS_NO_INFO;
7431 }
7432 } else {
7433 l2cap_state_change(chan, BT_DISCONN);
7434 __set_chan_timer(chan, L2CAP_DISC_TIMEOUT);
7435 res = L2CAP_CR_SEC_BLOCK;
7436 stat = L2CAP_CS_NO_INFO;
7437 }
7438
7439 rsp.scid = cpu_to_le16(chan->dcid);
7440 rsp.dcid = cpu_to_le16(chan->scid);
7441 rsp.result = cpu_to_le16(res);
7442 rsp.status = cpu_to_le16(stat);
7443 l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_RSP,
7444 sizeof(rsp), &rsp);
7445
7446 if (!test_bit(CONF_REQ_SENT, &chan->conf_state) &&
7447 res == L2CAP_CR_SUCCESS) {
7448 char buf[128];
7449 set_bit(CONF_REQ_SENT, &chan->conf_state);
7450 l2cap_send_cmd(conn, l2cap_get_ident(conn),
7451 L2CAP_CONF_REQ,
7452 l2cap_build_conf_req(chan, buf),
7453 buf);
7454 chan->num_conf_req++;
7455 }
7456 }
7457
7458 l2cap_chan_unlock(chan);
7459 }
7460
7461 mutex_unlock(&conn->chan_lock);
7462}
7463
7464void l2cap_recv_acldata(struct hci_conn *hcon, struct sk_buff *skb, u16 flags)
7465{
7466 struct l2cap_conn *conn = hcon->l2cap_data;
7467 struct l2cap_hdr *hdr;
7468 int len;
7469
7470 /* For AMP controller do not create l2cap conn */
7471 if (!conn && hcon->hdev->dev_type != HCI_BREDR)
7472 goto drop;
7473
7474 if (!conn)
7475 conn = l2cap_conn_add(hcon);
7476
7477 if (!conn)
7478 goto drop;
7479
7480 BT_DBG("conn %p len %d flags 0x%x", conn, skb->len, flags);
7481
7482 switch (flags) {
7483 case ACL_START:
7484 case ACL_START_NO_FLUSH:
7485 case ACL_COMPLETE:
7486 if (conn->rx_len) {
7487 BT_ERR("Unexpected start frame (len %d)", skb->len);
7488 kfree_skb(conn->rx_skb);
7489 conn->rx_skb = NULL;
7490 conn->rx_len = 0;
7491 l2cap_conn_unreliable(conn, ECOMM);
7492 }
7493
7494 /* Start fragment always begin with Basic L2CAP header */
7495 if (skb->len < L2CAP_HDR_SIZE) {
7496 BT_ERR("Frame is too short (len %d)", skb->len);
7497 l2cap_conn_unreliable(conn, ECOMM);
7498 goto drop;
7499 }
7500
7501 hdr = (struct l2cap_hdr *) skb->data;
7502 len = __le16_to_cpu(hdr->len) + L2CAP_HDR_SIZE;
7503
7504 if (len == skb->len) {
7505 /* Complete frame received */
7506 l2cap_recv_frame(conn, skb);
7507 return;
7508 }
7509
7510 BT_DBG("Start: total len %d, frag len %d", len, skb->len);
7511
7512 if (skb->len > len) {
7513 BT_ERR("Frame is too long (len %d, expected len %d)",
7514 skb->len, len);
7515 l2cap_conn_unreliable(conn, ECOMM);
7516 goto drop;
7517 }
7518
7519 /* Allocate skb for the complete frame (with header) */
7520 conn->rx_skb = bt_skb_alloc(len, GFP_KERNEL);
7521 if (!conn->rx_skb)
7522 goto drop;
7523
7524 skb_copy_from_linear_data(skb, skb_put(conn->rx_skb, skb->len),
7525 skb->len);
7526 conn->rx_len = len - skb->len;
7527 break;
7528
7529 case ACL_CONT:
7530 BT_DBG("Cont: frag len %d (expecting %d)", skb->len, conn->rx_len);
7531
7532 if (!conn->rx_len) {
7533 BT_ERR("Unexpected continuation frame (len %d)", skb->len);
7534 l2cap_conn_unreliable(conn, ECOMM);
7535 goto drop;
7536 }
7537
7538 if (skb->len > conn->rx_len) {
7539 BT_ERR("Fragment is too long (len %d, expected %d)",
7540 skb->len, conn->rx_len);
7541 kfree_skb(conn->rx_skb);
7542 conn->rx_skb = NULL;
7543 conn->rx_len = 0;
7544 l2cap_conn_unreliable(conn, ECOMM);
7545 goto drop;
7546 }
7547
7548 skb_copy_from_linear_data(skb, skb_put(conn->rx_skb, skb->len),
7549 skb->len);
7550 conn->rx_len -= skb->len;
7551
7552 if (!conn->rx_len) {
7553 /* Complete frame received. l2cap_recv_frame
7554 * takes ownership of the skb so set the global
7555 * rx_skb pointer to NULL first.
7556 */
7557 struct sk_buff *rx_skb = conn->rx_skb;
7558 conn->rx_skb = NULL;
7559 l2cap_recv_frame(conn, rx_skb);
7560 }
7561 break;
7562 }
7563
7564drop:
7565 kfree_skb(skb);
7566}
7567
7568static struct hci_cb l2cap_cb = {
7569 .name = "L2CAP",
7570 .connect_cfm = l2cap_connect_cfm,
7571 .disconn_cfm = l2cap_disconn_cfm,
7572 .security_cfm = l2cap_security_cfm,
7573};
7574
7575static int l2cap_debugfs_show(struct seq_file *f, void *p)
7576{
7577 struct l2cap_chan *c;
7578
7579 read_lock(&chan_list_lock);
7580
7581 list_for_each_entry(c, &chan_list, global_l) {
7582 seq_printf(f, "%pMR (%u) %pMR (%u) %d %d 0x%4.4x 0x%4.4x %d %d %d %d\n",
7583 &c->src, c->src_type, &c->dst, c->dst_type,
7584 c->state, __le16_to_cpu(c->psm),
7585 c->scid, c->dcid, c->imtu, c->omtu,
7586 c->sec_level, c->mode);
7587 }
7588
7589 read_unlock(&chan_list_lock);
7590
7591 return 0;
7592}
7593
7594static int l2cap_debugfs_open(struct inode *inode, struct file *file)
7595{
7596 return single_open(file, l2cap_debugfs_show, inode->i_private);
7597}
7598
7599static const struct file_operations l2cap_debugfs_fops = {
7600 .open = l2cap_debugfs_open,
7601 .read = seq_read,
7602 .llseek = seq_lseek,
7603 .release = single_release,
7604};
7605
7606static struct dentry *l2cap_debugfs;
7607
7608int __init l2cap_init(void)
7609{
7610 int err;
7611
7612 err = l2cap_init_sockets();
7613 if (err < 0)
7614 return err;
7615
7616 hci_register_cb(&l2cap_cb);
7617
7618 if (IS_ERR_OR_NULL(bt_debugfs))
7619 return 0;
7620
7621 l2cap_debugfs = debugfs_create_file("l2cap", 0444, bt_debugfs,
7622 NULL, &l2cap_debugfs_fops);
7623
7624 debugfs_create_u16("l2cap_le_max_credits", 0644, bt_debugfs,
7625 &le_max_credits);
7626 debugfs_create_u16("l2cap_le_default_mps", 0644, bt_debugfs,
7627 &le_default_mps);
7628
7629 return 0;
7630}
7631
7632void l2cap_exit(void)
7633{
7634 debugfs_remove(l2cap_debugfs);
7635 hci_unregister_cb(&l2cap_cb);
7636 l2cap_cleanup_sockets();
7637}
7638
7639module_param(disable_ertm, bool, 0644);
7640MODULE_PARM_DESC(disable_ertm, "Disable enhanced retransmission 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;
48bool enable_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);
64
65static inline u8 bdaddr_type(u8 link_type, u8 bdaddr_type)
66{
67 if (link_type == LE_LINK) {
68 if (bdaddr_type == ADDR_LE_DEV_PUBLIC)
69 return BDADDR_LE_PUBLIC;
70 else
71 return BDADDR_LE_RANDOM;
72 }
73
74 return BDADDR_BREDR;
75}
76
77static inline u8 bdaddr_src_type(struct hci_conn *hcon)
78{
79 return bdaddr_type(hcon->type, hcon->src_type);
80}
81
82static inline u8 bdaddr_dst_type(struct hci_conn *hcon)
83{
84 return bdaddr_type(hcon->type, hcon->dst_type);
85}
86
87/* ---- L2CAP channels ---- */
88
89static struct l2cap_chan *__l2cap_get_chan_by_dcid(struct l2cap_conn *conn,
90 u16 cid)
91{
92 struct l2cap_chan *c;
93
94 list_for_each_entry(c, &conn->chan_l, list) {
95 if (c->dcid == cid)
96 return c;
97 }
98 return NULL;
99}
100
101static struct l2cap_chan *__l2cap_get_chan_by_scid(struct l2cap_conn *conn,
102 u16 cid)
103{
104 struct l2cap_chan *c;
105
106 list_for_each_entry(c, &conn->chan_l, list) {
107 if (c->scid == cid)
108 return c;
109 }
110 return NULL;
111}
112
113/* Find channel with given SCID.
114 * Returns locked channel. */
115static struct l2cap_chan *l2cap_get_chan_by_scid(struct l2cap_conn *conn,
116 u16 cid)
117{
118 struct l2cap_chan *c;
119
120 mutex_lock(&conn->chan_lock);
121 c = __l2cap_get_chan_by_scid(conn, cid);
122 if (c)
123 l2cap_chan_lock(c);
124 mutex_unlock(&conn->chan_lock);
125
126 return c;
127}
128
129/* Find channel with given DCID.
130 * Returns locked channel.
131 */
132static struct l2cap_chan *l2cap_get_chan_by_dcid(struct l2cap_conn *conn,
133 u16 cid)
134{
135 struct l2cap_chan *c;
136
137 mutex_lock(&conn->chan_lock);
138 c = __l2cap_get_chan_by_dcid(conn, cid);
139 if (c)
140 l2cap_chan_lock(c);
141 mutex_unlock(&conn->chan_lock);
142
143 return c;
144}
145
146static struct l2cap_chan *__l2cap_get_chan_by_ident(struct l2cap_conn *conn,
147 u8 ident)
148{
149 struct l2cap_chan *c;
150
151 list_for_each_entry(c, &conn->chan_l, list) {
152 if (c->ident == ident)
153 return c;
154 }
155 return NULL;
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 mutex_lock(&conn->chan_lock);
164 c = __l2cap_get_chan_by_ident(conn, ident);
165 if (c)
166 l2cap_chan_lock(c);
167 mutex_unlock(&conn->chan_lock);
168
169 return c;
170}
171
172static struct l2cap_chan *__l2cap_global_chan_by_addr(__le16 psm, bdaddr_t *src,
173 u8 src_type)
174{
175 struct l2cap_chan *c;
176
177 list_for_each_entry(c, &chan_list, global_l) {
178 if (src_type == BDADDR_BREDR && c->src_type != BDADDR_BREDR)
179 continue;
180
181 if (src_type != BDADDR_BREDR && c->src_type == BDADDR_BREDR)
182 continue;
183
184 if (c->sport == psm && !bacmp(&c->src, src))
185 return c;
186 }
187 return NULL;
188}
189
190int l2cap_add_psm(struct l2cap_chan *chan, bdaddr_t *src, __le16 psm)
191{
192 int err;
193
194 write_lock(&chan_list_lock);
195
196 if (psm && __l2cap_global_chan_by_addr(psm, src, chan->src_type)) {
197 err = -EADDRINUSE;
198 goto done;
199 }
200
201 if (psm) {
202 chan->psm = psm;
203 chan->sport = psm;
204 err = 0;
205 } else {
206 u16 p, start, end, incr;
207
208 if (chan->src_type == BDADDR_BREDR) {
209 start = L2CAP_PSM_DYN_START;
210 end = L2CAP_PSM_AUTO_END;
211 incr = 2;
212 } else {
213 start = L2CAP_PSM_LE_DYN_START;
214 end = L2CAP_PSM_LE_DYN_END;
215 incr = 1;
216 }
217
218 err = -EINVAL;
219 for (p = start; p <= end; p += incr)
220 if (!__l2cap_global_chan_by_addr(cpu_to_le16(p), src,
221 chan->src_type)) {
222 chan->psm = cpu_to_le16(p);
223 chan->sport = cpu_to_le16(p);
224 err = 0;
225 break;
226 }
227 }
228
229done:
230 write_unlock(&chan_list_lock);
231 return err;
232}
233EXPORT_SYMBOL_GPL(l2cap_add_psm);
234
235int l2cap_add_scid(struct l2cap_chan *chan, __u16 scid)
236{
237 write_lock(&chan_list_lock);
238
239 /* Override the defaults (which are for conn-oriented) */
240 chan->omtu = L2CAP_DEFAULT_MTU;
241 chan->chan_type = L2CAP_CHAN_FIXED;
242
243 chan->scid = scid;
244
245 write_unlock(&chan_list_lock);
246
247 return 0;
248}
249
250static u16 l2cap_alloc_cid(struct l2cap_conn *conn)
251{
252 u16 cid, dyn_end;
253
254 if (conn->hcon->type == LE_LINK)
255 dyn_end = L2CAP_CID_LE_DYN_END;
256 else
257 dyn_end = L2CAP_CID_DYN_END;
258
259 for (cid = L2CAP_CID_DYN_START; cid <= dyn_end; cid++) {
260 if (!__l2cap_get_chan_by_scid(conn, cid))
261 return cid;
262 }
263
264 return 0;
265}
266
267static void l2cap_state_change(struct l2cap_chan *chan, int state)
268{
269 BT_DBG("chan %p %s -> %s", chan, state_to_string(chan->state),
270 state_to_string(state));
271
272 chan->state = state;
273 chan->ops->state_change(chan, state, 0);
274}
275
276static inline void l2cap_state_change_and_error(struct l2cap_chan *chan,
277 int state, int err)
278{
279 chan->state = state;
280 chan->ops->state_change(chan, chan->state, err);
281}
282
283static inline void l2cap_chan_set_err(struct l2cap_chan *chan, int err)
284{
285 chan->ops->state_change(chan, chan->state, err);
286}
287
288static void __set_retrans_timer(struct l2cap_chan *chan)
289{
290 if (!delayed_work_pending(&chan->monitor_timer) &&
291 chan->retrans_timeout) {
292 l2cap_set_timer(chan, &chan->retrans_timer,
293 msecs_to_jiffies(chan->retrans_timeout));
294 }
295}
296
297static void __set_monitor_timer(struct l2cap_chan *chan)
298{
299 __clear_retrans_timer(chan);
300 if (chan->monitor_timeout) {
301 l2cap_set_timer(chan, &chan->monitor_timer,
302 msecs_to_jiffies(chan->monitor_timeout));
303 }
304}
305
306static struct sk_buff *l2cap_ertm_seq_in_queue(struct sk_buff_head *head,
307 u16 seq)
308{
309 struct sk_buff *skb;
310
311 skb_queue_walk(head, skb) {
312 if (bt_cb(skb)->l2cap.txseq == seq)
313 return skb;
314 }
315
316 return NULL;
317}
318
319/* ---- L2CAP sequence number lists ---- */
320
321/* For ERTM, ordered lists of sequence numbers must be tracked for
322 * SREJ requests that are received and for frames that are to be
323 * retransmitted. These seq_list functions implement a singly-linked
324 * list in an array, where membership in the list can also be checked
325 * in constant time. Items can also be added to the tail of the list
326 * and removed from the head in constant time, without further memory
327 * allocs or frees.
328 */
329
330static int l2cap_seq_list_init(struct l2cap_seq_list *seq_list, u16 size)
331{
332 size_t alloc_size, i;
333
334 /* Allocated size is a power of 2 to map sequence numbers
335 * (which may be up to 14 bits) in to a smaller array that is
336 * sized for the negotiated ERTM transmit windows.
337 */
338 alloc_size = roundup_pow_of_two(size);
339
340 seq_list->list = kmalloc_array(alloc_size, sizeof(u16), GFP_KERNEL);
341 if (!seq_list->list)
342 return -ENOMEM;
343
344 seq_list->mask = alloc_size - 1;
345 seq_list->head = L2CAP_SEQ_LIST_CLEAR;
346 seq_list->tail = L2CAP_SEQ_LIST_CLEAR;
347 for (i = 0; i < alloc_size; i++)
348 seq_list->list[i] = L2CAP_SEQ_LIST_CLEAR;
349
350 return 0;
351}
352
353static inline void l2cap_seq_list_free(struct l2cap_seq_list *seq_list)
354{
355 kfree(seq_list->list);
356}
357
358static inline bool l2cap_seq_list_contains(struct l2cap_seq_list *seq_list,
359 u16 seq)
360{
361 /* Constant-time check for list membership */
362 return seq_list->list[seq & seq_list->mask] != L2CAP_SEQ_LIST_CLEAR;
363}
364
365static inline u16 l2cap_seq_list_pop(struct l2cap_seq_list *seq_list)
366{
367 u16 seq = seq_list->head;
368 u16 mask = seq_list->mask;
369
370 seq_list->head = seq_list->list[seq & mask];
371 seq_list->list[seq & mask] = L2CAP_SEQ_LIST_CLEAR;
372
373 if (seq_list->head == L2CAP_SEQ_LIST_TAIL) {
374 seq_list->head = L2CAP_SEQ_LIST_CLEAR;
375 seq_list->tail = L2CAP_SEQ_LIST_CLEAR;
376 }
377
378 return seq;
379}
380
381static void l2cap_seq_list_clear(struct l2cap_seq_list *seq_list)
382{
383 u16 i;
384
385 if (seq_list->head == L2CAP_SEQ_LIST_CLEAR)
386 return;
387
388 for (i = 0; i <= seq_list->mask; i++)
389 seq_list->list[i] = L2CAP_SEQ_LIST_CLEAR;
390
391 seq_list->head = L2CAP_SEQ_LIST_CLEAR;
392 seq_list->tail = L2CAP_SEQ_LIST_CLEAR;
393}
394
395static void l2cap_seq_list_append(struct l2cap_seq_list *seq_list, u16 seq)
396{
397 u16 mask = seq_list->mask;
398
399 /* All appends happen in constant time */
400
401 if (seq_list->list[seq & mask] != L2CAP_SEQ_LIST_CLEAR)
402 return;
403
404 if (seq_list->tail == L2CAP_SEQ_LIST_CLEAR)
405 seq_list->head = seq;
406 else
407 seq_list->list[seq_list->tail & mask] = seq;
408
409 seq_list->tail = seq;
410 seq_list->list[seq & mask] = L2CAP_SEQ_LIST_TAIL;
411}
412
413static void l2cap_chan_timeout(struct work_struct *work)
414{
415 struct l2cap_chan *chan = container_of(work, struct l2cap_chan,
416 chan_timer.work);
417 struct l2cap_conn *conn = chan->conn;
418 int reason;
419
420 BT_DBG("chan %p state %s", chan, state_to_string(chan->state));
421
422 mutex_lock(&conn->chan_lock);
423 /* __set_chan_timer() calls l2cap_chan_hold(chan) while scheduling
424 * this work. No need to call l2cap_chan_hold(chan) here again.
425 */
426 l2cap_chan_lock(chan);
427
428 if (chan->state == BT_CONNECTED || chan->state == BT_CONFIG)
429 reason = ECONNREFUSED;
430 else if (chan->state == BT_CONNECT &&
431 chan->sec_level != BT_SECURITY_SDP)
432 reason = ECONNREFUSED;
433 else
434 reason = ETIMEDOUT;
435
436 l2cap_chan_close(chan, reason);
437
438 chan->ops->close(chan);
439
440 l2cap_chan_unlock(chan);
441 l2cap_chan_put(chan);
442
443 mutex_unlock(&conn->chan_lock);
444}
445
446struct l2cap_chan *l2cap_chan_create(void)
447{
448 struct l2cap_chan *chan;
449
450 chan = kzalloc(sizeof(*chan), GFP_ATOMIC);
451 if (!chan)
452 return NULL;
453
454 mutex_init(&chan->lock);
455
456 /* Set default lock nesting level */
457 atomic_set(&chan->nesting, L2CAP_NESTING_NORMAL);
458
459 write_lock(&chan_list_lock);
460 list_add(&chan->global_l, &chan_list);
461 write_unlock(&chan_list_lock);
462
463 INIT_DELAYED_WORK(&chan->chan_timer, l2cap_chan_timeout);
464
465 chan->state = BT_OPEN;
466
467 kref_init(&chan->kref);
468
469 /* This flag is cleared in l2cap_chan_ready() */
470 set_bit(CONF_NOT_COMPLETE, &chan->conf_state);
471
472 BT_DBG("chan %p", chan);
473
474 return chan;
475}
476EXPORT_SYMBOL_GPL(l2cap_chan_create);
477
478static void l2cap_chan_destroy(struct kref *kref)
479{
480 struct l2cap_chan *chan = container_of(kref, struct l2cap_chan, kref);
481
482 BT_DBG("chan %p", chan);
483
484 write_lock(&chan_list_lock);
485 list_del(&chan->global_l);
486 write_unlock(&chan_list_lock);
487
488 kfree(chan);
489}
490
491void l2cap_chan_hold(struct l2cap_chan *c)
492{
493 BT_DBG("chan %p orig refcnt %d", c, kref_read(&c->kref));
494
495 kref_get(&c->kref);
496}
497
498void l2cap_chan_put(struct l2cap_chan *c)
499{
500 BT_DBG("chan %p orig refcnt %d", c, kref_read(&c->kref));
501
502 kref_put(&c->kref, l2cap_chan_destroy);
503}
504EXPORT_SYMBOL_GPL(l2cap_chan_put);
505
506void l2cap_chan_set_defaults(struct l2cap_chan *chan)
507{
508 chan->fcs = L2CAP_FCS_CRC16;
509 chan->max_tx = L2CAP_DEFAULT_MAX_TX;
510 chan->tx_win = L2CAP_DEFAULT_TX_WINDOW;
511 chan->tx_win_max = L2CAP_DEFAULT_TX_WINDOW;
512 chan->remote_max_tx = chan->max_tx;
513 chan->remote_tx_win = chan->tx_win;
514 chan->ack_win = L2CAP_DEFAULT_TX_WINDOW;
515 chan->sec_level = BT_SECURITY_LOW;
516 chan->flush_to = L2CAP_DEFAULT_FLUSH_TO;
517 chan->retrans_timeout = L2CAP_DEFAULT_RETRANS_TO;
518 chan->monitor_timeout = L2CAP_DEFAULT_MONITOR_TO;
519 chan->conf_state = 0;
520
521 set_bit(FLAG_FORCE_ACTIVE, &chan->flags);
522}
523EXPORT_SYMBOL_GPL(l2cap_chan_set_defaults);
524
525static void l2cap_le_flowctl_init(struct l2cap_chan *chan, u16 tx_credits)
526{
527 chan->sdu = NULL;
528 chan->sdu_last_frag = NULL;
529 chan->sdu_len = 0;
530 chan->tx_credits = tx_credits;
531 /* Derive MPS from connection MTU to stop HCI fragmentation */
532 chan->mps = min_t(u16, chan->imtu, chan->conn->mtu - L2CAP_HDR_SIZE);
533 /* Give enough credits for a full packet */
534 chan->rx_credits = (chan->imtu / chan->mps) + 1;
535
536 skb_queue_head_init(&chan->tx_q);
537}
538
539static void l2cap_ecred_init(struct l2cap_chan *chan, u16 tx_credits)
540{
541 l2cap_le_flowctl_init(chan, tx_credits);
542
543 /* L2CAP implementations shall support a minimum MPS of 64 octets */
544 if (chan->mps < L2CAP_ECRED_MIN_MPS) {
545 chan->mps = L2CAP_ECRED_MIN_MPS;
546 chan->rx_credits = (chan->imtu / chan->mps) + 1;
547 }
548}
549
550void __l2cap_chan_add(struct l2cap_conn *conn, struct l2cap_chan *chan)
551{
552 BT_DBG("conn %p, psm 0x%2.2x, dcid 0x%4.4x", conn,
553 __le16_to_cpu(chan->psm), chan->dcid);
554
555 conn->disc_reason = HCI_ERROR_REMOTE_USER_TERM;
556
557 chan->conn = conn;
558
559 switch (chan->chan_type) {
560 case L2CAP_CHAN_CONN_ORIENTED:
561 /* Alloc CID for connection-oriented socket */
562 chan->scid = l2cap_alloc_cid(conn);
563 if (conn->hcon->type == ACL_LINK)
564 chan->omtu = L2CAP_DEFAULT_MTU;
565 break;
566
567 case L2CAP_CHAN_CONN_LESS:
568 /* Connectionless socket */
569 chan->scid = L2CAP_CID_CONN_LESS;
570 chan->dcid = L2CAP_CID_CONN_LESS;
571 chan->omtu = L2CAP_DEFAULT_MTU;
572 break;
573
574 case L2CAP_CHAN_FIXED:
575 /* Caller will set CID and CID specific MTU values */
576 break;
577
578 default:
579 /* Raw socket can send/recv signalling messages only */
580 chan->scid = L2CAP_CID_SIGNALING;
581 chan->dcid = L2CAP_CID_SIGNALING;
582 chan->omtu = L2CAP_DEFAULT_MTU;
583 }
584
585 chan->local_id = L2CAP_BESTEFFORT_ID;
586 chan->local_stype = L2CAP_SERV_BESTEFFORT;
587 chan->local_msdu = L2CAP_DEFAULT_MAX_SDU_SIZE;
588 chan->local_sdu_itime = L2CAP_DEFAULT_SDU_ITIME;
589 chan->local_acc_lat = L2CAP_DEFAULT_ACC_LAT;
590 chan->local_flush_to = L2CAP_EFS_DEFAULT_FLUSH_TO;
591
592 l2cap_chan_hold(chan);
593
594 /* Only keep a reference for fixed channels if they requested it */
595 if (chan->chan_type != L2CAP_CHAN_FIXED ||
596 test_bit(FLAG_HOLD_HCI_CONN, &chan->flags))
597 hci_conn_hold(conn->hcon);
598
599 list_add(&chan->list, &conn->chan_l);
600}
601
602void l2cap_chan_add(struct l2cap_conn *conn, struct l2cap_chan *chan)
603{
604 mutex_lock(&conn->chan_lock);
605 __l2cap_chan_add(conn, chan);
606 mutex_unlock(&conn->chan_lock);
607}
608
609void l2cap_chan_del(struct l2cap_chan *chan, int err)
610{
611 struct l2cap_conn *conn = chan->conn;
612
613 __clear_chan_timer(chan);
614
615 BT_DBG("chan %p, conn %p, err %d, state %s", chan, conn, err,
616 state_to_string(chan->state));
617
618 chan->ops->teardown(chan, err);
619
620 if (conn) {
621 struct amp_mgr *mgr = conn->hcon->amp_mgr;
622 /* Delete from channel list */
623 list_del(&chan->list);
624
625 l2cap_chan_put(chan);
626
627 chan->conn = NULL;
628
629 /* Reference was only held for non-fixed channels or
630 * fixed channels that explicitly requested it using the
631 * FLAG_HOLD_HCI_CONN flag.
632 */
633 if (chan->chan_type != L2CAP_CHAN_FIXED ||
634 test_bit(FLAG_HOLD_HCI_CONN, &chan->flags))
635 hci_conn_drop(conn->hcon);
636
637 if (mgr && mgr->bredr_chan == chan)
638 mgr->bredr_chan = NULL;
639 }
640
641 if (chan->hs_hchan) {
642 struct hci_chan *hs_hchan = chan->hs_hchan;
643
644 BT_DBG("chan %p disconnect hs_hchan %p", chan, hs_hchan);
645 amp_disconnect_logical_link(hs_hchan);
646 }
647
648 if (test_bit(CONF_NOT_COMPLETE, &chan->conf_state))
649 return;
650
651 switch(chan->mode) {
652 case L2CAP_MODE_BASIC:
653 break;
654
655 case L2CAP_MODE_LE_FLOWCTL:
656 case L2CAP_MODE_EXT_FLOWCTL:
657 skb_queue_purge(&chan->tx_q);
658 break;
659
660 case L2CAP_MODE_ERTM:
661 __clear_retrans_timer(chan);
662 __clear_monitor_timer(chan);
663 __clear_ack_timer(chan);
664
665 skb_queue_purge(&chan->srej_q);
666
667 l2cap_seq_list_free(&chan->srej_list);
668 l2cap_seq_list_free(&chan->retrans_list);
669 fallthrough;
670
671 case L2CAP_MODE_STREAMING:
672 skb_queue_purge(&chan->tx_q);
673 break;
674 }
675
676 return;
677}
678EXPORT_SYMBOL_GPL(l2cap_chan_del);
679
680static void __l2cap_chan_list(struct l2cap_conn *conn, l2cap_chan_func_t func,
681 void *data)
682{
683 struct l2cap_chan *chan;
684
685 list_for_each_entry(chan, &conn->chan_l, list) {
686 func(chan, data);
687 }
688}
689
690void l2cap_chan_list(struct l2cap_conn *conn, l2cap_chan_func_t func,
691 void *data)
692{
693 if (!conn)
694 return;
695
696 mutex_lock(&conn->chan_lock);
697 __l2cap_chan_list(conn, func, data);
698 mutex_unlock(&conn->chan_lock);
699}
700
701EXPORT_SYMBOL_GPL(l2cap_chan_list);
702
703static void l2cap_conn_update_id_addr(struct work_struct *work)
704{
705 struct l2cap_conn *conn = container_of(work, struct l2cap_conn,
706 id_addr_update_work);
707 struct hci_conn *hcon = conn->hcon;
708 struct l2cap_chan *chan;
709
710 mutex_lock(&conn->chan_lock);
711
712 list_for_each_entry(chan, &conn->chan_l, list) {
713 l2cap_chan_lock(chan);
714 bacpy(&chan->dst, &hcon->dst);
715 chan->dst_type = bdaddr_dst_type(hcon);
716 l2cap_chan_unlock(chan);
717 }
718
719 mutex_unlock(&conn->chan_lock);
720}
721
722static void l2cap_chan_le_connect_reject(struct l2cap_chan *chan)
723{
724 struct l2cap_conn *conn = chan->conn;
725 struct l2cap_le_conn_rsp rsp;
726 u16 result;
727
728 if (test_bit(FLAG_DEFER_SETUP, &chan->flags))
729 result = L2CAP_CR_LE_AUTHORIZATION;
730 else
731 result = L2CAP_CR_LE_BAD_PSM;
732
733 l2cap_state_change(chan, BT_DISCONN);
734
735 rsp.dcid = cpu_to_le16(chan->scid);
736 rsp.mtu = cpu_to_le16(chan->imtu);
737 rsp.mps = cpu_to_le16(chan->mps);
738 rsp.credits = cpu_to_le16(chan->rx_credits);
739 rsp.result = cpu_to_le16(result);
740
741 l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CONN_RSP, sizeof(rsp),
742 &rsp);
743}
744
745static void l2cap_chan_ecred_connect_reject(struct l2cap_chan *chan)
746{
747 struct l2cap_conn *conn = chan->conn;
748 struct l2cap_ecred_conn_rsp rsp;
749 u16 result;
750
751 if (test_bit(FLAG_DEFER_SETUP, &chan->flags))
752 result = L2CAP_CR_LE_AUTHORIZATION;
753 else
754 result = L2CAP_CR_LE_BAD_PSM;
755
756 l2cap_state_change(chan, BT_DISCONN);
757
758 memset(&rsp, 0, sizeof(rsp));
759
760 rsp.result = cpu_to_le16(result);
761
762 l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CONN_RSP, sizeof(rsp),
763 &rsp);
764}
765
766static void l2cap_chan_connect_reject(struct l2cap_chan *chan)
767{
768 struct l2cap_conn *conn = chan->conn;
769 struct l2cap_conn_rsp rsp;
770 u16 result;
771
772 if (test_bit(FLAG_DEFER_SETUP, &chan->flags))
773 result = L2CAP_CR_SEC_BLOCK;
774 else
775 result = L2CAP_CR_BAD_PSM;
776
777 l2cap_state_change(chan, BT_DISCONN);
778
779 rsp.scid = cpu_to_le16(chan->dcid);
780 rsp.dcid = cpu_to_le16(chan->scid);
781 rsp.result = cpu_to_le16(result);
782 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
783
784 l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_RSP, sizeof(rsp), &rsp);
785}
786
787void l2cap_chan_close(struct l2cap_chan *chan, int reason)
788{
789 struct l2cap_conn *conn = chan->conn;
790
791 BT_DBG("chan %p state %s", chan, state_to_string(chan->state));
792
793 switch (chan->state) {
794 case BT_LISTEN:
795 chan->ops->teardown(chan, 0);
796 break;
797
798 case BT_CONNECTED:
799 case BT_CONFIG:
800 if (chan->chan_type == L2CAP_CHAN_CONN_ORIENTED) {
801 __set_chan_timer(chan, chan->ops->get_sndtimeo(chan));
802 l2cap_send_disconn_req(chan, reason);
803 } else
804 l2cap_chan_del(chan, reason);
805 break;
806
807 case BT_CONNECT2:
808 if (chan->chan_type == L2CAP_CHAN_CONN_ORIENTED) {
809 if (conn->hcon->type == ACL_LINK)
810 l2cap_chan_connect_reject(chan);
811 else if (conn->hcon->type == LE_LINK) {
812 switch (chan->mode) {
813 case L2CAP_MODE_LE_FLOWCTL:
814 l2cap_chan_le_connect_reject(chan);
815 break;
816 case L2CAP_MODE_EXT_FLOWCTL:
817 l2cap_chan_ecred_connect_reject(chan);
818 break;
819 }
820 }
821 }
822
823 l2cap_chan_del(chan, reason);
824 break;
825
826 case BT_CONNECT:
827 case BT_DISCONN:
828 l2cap_chan_del(chan, reason);
829 break;
830
831 default:
832 chan->ops->teardown(chan, 0);
833 break;
834 }
835}
836EXPORT_SYMBOL(l2cap_chan_close);
837
838static inline u8 l2cap_get_auth_type(struct l2cap_chan *chan)
839{
840 switch (chan->chan_type) {
841 case L2CAP_CHAN_RAW:
842 switch (chan->sec_level) {
843 case BT_SECURITY_HIGH:
844 case BT_SECURITY_FIPS:
845 return HCI_AT_DEDICATED_BONDING_MITM;
846 case BT_SECURITY_MEDIUM:
847 return HCI_AT_DEDICATED_BONDING;
848 default:
849 return HCI_AT_NO_BONDING;
850 }
851 break;
852 case L2CAP_CHAN_CONN_LESS:
853 if (chan->psm == cpu_to_le16(L2CAP_PSM_3DSP)) {
854 if (chan->sec_level == BT_SECURITY_LOW)
855 chan->sec_level = BT_SECURITY_SDP;
856 }
857 if (chan->sec_level == BT_SECURITY_HIGH ||
858 chan->sec_level == BT_SECURITY_FIPS)
859 return HCI_AT_NO_BONDING_MITM;
860 else
861 return HCI_AT_NO_BONDING;
862 break;
863 case L2CAP_CHAN_CONN_ORIENTED:
864 if (chan->psm == cpu_to_le16(L2CAP_PSM_SDP)) {
865 if (chan->sec_level == BT_SECURITY_LOW)
866 chan->sec_level = BT_SECURITY_SDP;
867
868 if (chan->sec_level == BT_SECURITY_HIGH ||
869 chan->sec_level == BT_SECURITY_FIPS)
870 return HCI_AT_NO_BONDING_MITM;
871 else
872 return HCI_AT_NO_BONDING;
873 }
874 fallthrough;
875
876 default:
877 switch (chan->sec_level) {
878 case BT_SECURITY_HIGH:
879 case BT_SECURITY_FIPS:
880 return HCI_AT_GENERAL_BONDING_MITM;
881 case BT_SECURITY_MEDIUM:
882 return HCI_AT_GENERAL_BONDING;
883 default:
884 return HCI_AT_NO_BONDING;
885 }
886 break;
887 }
888}
889
890/* Service level security */
891int l2cap_chan_check_security(struct l2cap_chan *chan, bool initiator)
892{
893 struct l2cap_conn *conn = chan->conn;
894 __u8 auth_type;
895
896 if (conn->hcon->type == LE_LINK)
897 return smp_conn_security(conn->hcon, chan->sec_level);
898
899 auth_type = l2cap_get_auth_type(chan);
900
901 return hci_conn_security(conn->hcon, chan->sec_level, auth_type,
902 initiator);
903}
904
905static u8 l2cap_get_ident(struct l2cap_conn *conn)
906{
907 u8 id;
908
909 /* Get next available identificator.
910 * 1 - 128 are used by kernel.
911 * 129 - 199 are reserved.
912 * 200 - 254 are used by utilities like l2ping, etc.
913 */
914
915 mutex_lock(&conn->ident_lock);
916
917 if (++conn->tx_ident > 128)
918 conn->tx_ident = 1;
919
920 id = conn->tx_ident;
921
922 mutex_unlock(&conn->ident_lock);
923
924 return id;
925}
926
927static void l2cap_send_cmd(struct l2cap_conn *conn, u8 ident, u8 code, u16 len,
928 void *data)
929{
930 struct sk_buff *skb = l2cap_build_cmd(conn, code, ident, len, data);
931 u8 flags;
932
933 BT_DBG("code 0x%2.2x", code);
934
935 if (!skb)
936 return;
937
938 /* Use NO_FLUSH if supported or we have an LE link (which does
939 * not support auto-flushing packets) */
940 if (lmp_no_flush_capable(conn->hcon->hdev) ||
941 conn->hcon->type == LE_LINK)
942 flags = ACL_START_NO_FLUSH;
943 else
944 flags = ACL_START;
945
946 bt_cb(skb)->force_active = BT_POWER_FORCE_ACTIVE_ON;
947 skb->priority = HCI_PRIO_MAX;
948
949 hci_send_acl(conn->hchan, skb, flags);
950}
951
952static bool __chan_is_moving(struct l2cap_chan *chan)
953{
954 return chan->move_state != L2CAP_MOVE_STABLE &&
955 chan->move_state != L2CAP_MOVE_WAIT_PREPARE;
956}
957
958static void l2cap_do_send(struct l2cap_chan *chan, struct sk_buff *skb)
959{
960 struct hci_conn *hcon = chan->conn->hcon;
961 u16 flags;
962
963 BT_DBG("chan %p, skb %p len %d priority %u", chan, skb, skb->len,
964 skb->priority);
965
966 if (chan->hs_hcon && !__chan_is_moving(chan)) {
967 if (chan->hs_hchan)
968 hci_send_acl(chan->hs_hchan, skb, ACL_COMPLETE);
969 else
970 kfree_skb(skb);
971
972 return;
973 }
974
975 /* Use NO_FLUSH for LE links (where this is the only option) or
976 * if the BR/EDR link supports it and flushing has not been
977 * explicitly requested (through FLAG_FLUSHABLE).
978 */
979 if (hcon->type == LE_LINK ||
980 (!test_bit(FLAG_FLUSHABLE, &chan->flags) &&
981 lmp_no_flush_capable(hcon->hdev)))
982 flags = ACL_START_NO_FLUSH;
983 else
984 flags = ACL_START;
985
986 bt_cb(skb)->force_active = test_bit(FLAG_FORCE_ACTIVE, &chan->flags);
987 hci_send_acl(chan->conn->hchan, skb, flags);
988}
989
990static void __unpack_enhanced_control(u16 enh, struct l2cap_ctrl *control)
991{
992 control->reqseq = (enh & L2CAP_CTRL_REQSEQ) >> L2CAP_CTRL_REQSEQ_SHIFT;
993 control->final = (enh & L2CAP_CTRL_FINAL) >> L2CAP_CTRL_FINAL_SHIFT;
994
995 if (enh & L2CAP_CTRL_FRAME_TYPE) {
996 /* S-Frame */
997 control->sframe = 1;
998 control->poll = (enh & L2CAP_CTRL_POLL) >> L2CAP_CTRL_POLL_SHIFT;
999 control->super = (enh & L2CAP_CTRL_SUPERVISE) >> L2CAP_CTRL_SUPER_SHIFT;
1000
1001 control->sar = 0;
1002 control->txseq = 0;
1003 } else {
1004 /* I-Frame */
1005 control->sframe = 0;
1006 control->sar = (enh & L2CAP_CTRL_SAR) >> L2CAP_CTRL_SAR_SHIFT;
1007 control->txseq = (enh & L2CAP_CTRL_TXSEQ) >> L2CAP_CTRL_TXSEQ_SHIFT;
1008
1009 control->poll = 0;
1010 control->super = 0;
1011 }
1012}
1013
1014static void __unpack_extended_control(u32 ext, struct l2cap_ctrl *control)
1015{
1016 control->reqseq = (ext & L2CAP_EXT_CTRL_REQSEQ) >> L2CAP_EXT_CTRL_REQSEQ_SHIFT;
1017 control->final = (ext & L2CAP_EXT_CTRL_FINAL) >> L2CAP_EXT_CTRL_FINAL_SHIFT;
1018
1019 if (ext & L2CAP_EXT_CTRL_FRAME_TYPE) {
1020 /* S-Frame */
1021 control->sframe = 1;
1022 control->poll = (ext & L2CAP_EXT_CTRL_POLL) >> L2CAP_EXT_CTRL_POLL_SHIFT;
1023 control->super = (ext & L2CAP_EXT_CTRL_SUPERVISE) >> L2CAP_EXT_CTRL_SUPER_SHIFT;
1024
1025 control->sar = 0;
1026 control->txseq = 0;
1027 } else {
1028 /* I-Frame */
1029 control->sframe = 0;
1030 control->sar = (ext & L2CAP_EXT_CTRL_SAR) >> L2CAP_EXT_CTRL_SAR_SHIFT;
1031 control->txseq = (ext & L2CAP_EXT_CTRL_TXSEQ) >> L2CAP_EXT_CTRL_TXSEQ_SHIFT;
1032
1033 control->poll = 0;
1034 control->super = 0;
1035 }
1036}
1037
1038static inline void __unpack_control(struct l2cap_chan *chan,
1039 struct sk_buff *skb)
1040{
1041 if (test_bit(FLAG_EXT_CTRL, &chan->flags)) {
1042 __unpack_extended_control(get_unaligned_le32(skb->data),
1043 &bt_cb(skb)->l2cap);
1044 skb_pull(skb, L2CAP_EXT_CTRL_SIZE);
1045 } else {
1046 __unpack_enhanced_control(get_unaligned_le16(skb->data),
1047 &bt_cb(skb)->l2cap);
1048 skb_pull(skb, L2CAP_ENH_CTRL_SIZE);
1049 }
1050}
1051
1052static u32 __pack_extended_control(struct l2cap_ctrl *control)
1053{
1054 u32 packed;
1055
1056 packed = control->reqseq << L2CAP_EXT_CTRL_REQSEQ_SHIFT;
1057 packed |= control->final << L2CAP_EXT_CTRL_FINAL_SHIFT;
1058
1059 if (control->sframe) {
1060 packed |= control->poll << L2CAP_EXT_CTRL_POLL_SHIFT;
1061 packed |= control->super << L2CAP_EXT_CTRL_SUPER_SHIFT;
1062 packed |= L2CAP_EXT_CTRL_FRAME_TYPE;
1063 } else {
1064 packed |= control->sar << L2CAP_EXT_CTRL_SAR_SHIFT;
1065 packed |= control->txseq << L2CAP_EXT_CTRL_TXSEQ_SHIFT;
1066 }
1067
1068 return packed;
1069}
1070
1071static u16 __pack_enhanced_control(struct l2cap_ctrl *control)
1072{
1073 u16 packed;
1074
1075 packed = control->reqseq << L2CAP_CTRL_REQSEQ_SHIFT;
1076 packed |= control->final << L2CAP_CTRL_FINAL_SHIFT;
1077
1078 if (control->sframe) {
1079 packed |= control->poll << L2CAP_CTRL_POLL_SHIFT;
1080 packed |= control->super << L2CAP_CTRL_SUPER_SHIFT;
1081 packed |= L2CAP_CTRL_FRAME_TYPE;
1082 } else {
1083 packed |= control->sar << L2CAP_CTRL_SAR_SHIFT;
1084 packed |= control->txseq << L2CAP_CTRL_TXSEQ_SHIFT;
1085 }
1086
1087 return packed;
1088}
1089
1090static inline void __pack_control(struct l2cap_chan *chan,
1091 struct l2cap_ctrl *control,
1092 struct sk_buff *skb)
1093{
1094 if (test_bit(FLAG_EXT_CTRL, &chan->flags)) {
1095 put_unaligned_le32(__pack_extended_control(control),
1096 skb->data + L2CAP_HDR_SIZE);
1097 } else {
1098 put_unaligned_le16(__pack_enhanced_control(control),
1099 skb->data + L2CAP_HDR_SIZE);
1100 }
1101}
1102
1103static inline unsigned int __ertm_hdr_size(struct l2cap_chan *chan)
1104{
1105 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
1106 return L2CAP_EXT_HDR_SIZE;
1107 else
1108 return L2CAP_ENH_HDR_SIZE;
1109}
1110
1111static struct sk_buff *l2cap_create_sframe_pdu(struct l2cap_chan *chan,
1112 u32 control)
1113{
1114 struct sk_buff *skb;
1115 struct l2cap_hdr *lh;
1116 int hlen = __ertm_hdr_size(chan);
1117
1118 if (chan->fcs == L2CAP_FCS_CRC16)
1119 hlen += L2CAP_FCS_SIZE;
1120
1121 skb = bt_skb_alloc(hlen, GFP_KERNEL);
1122
1123 if (!skb)
1124 return ERR_PTR(-ENOMEM);
1125
1126 lh = skb_put(skb, L2CAP_HDR_SIZE);
1127 lh->len = cpu_to_le16(hlen - L2CAP_HDR_SIZE);
1128 lh->cid = cpu_to_le16(chan->dcid);
1129
1130 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
1131 put_unaligned_le32(control, skb_put(skb, L2CAP_EXT_CTRL_SIZE));
1132 else
1133 put_unaligned_le16(control, skb_put(skb, L2CAP_ENH_CTRL_SIZE));
1134
1135 if (chan->fcs == L2CAP_FCS_CRC16) {
1136 u16 fcs = crc16(0, (u8 *)skb->data, skb->len);
1137 put_unaligned_le16(fcs, skb_put(skb, L2CAP_FCS_SIZE));
1138 }
1139
1140 skb->priority = HCI_PRIO_MAX;
1141 return skb;
1142}
1143
1144static void l2cap_send_sframe(struct l2cap_chan *chan,
1145 struct l2cap_ctrl *control)
1146{
1147 struct sk_buff *skb;
1148 u32 control_field;
1149
1150 BT_DBG("chan %p, control %p", chan, control);
1151
1152 if (!control->sframe)
1153 return;
1154
1155 if (__chan_is_moving(chan))
1156 return;
1157
1158 if (test_and_clear_bit(CONN_SEND_FBIT, &chan->conn_state) &&
1159 !control->poll)
1160 control->final = 1;
1161
1162 if (control->super == L2CAP_SUPER_RR)
1163 clear_bit(CONN_RNR_SENT, &chan->conn_state);
1164 else if (control->super == L2CAP_SUPER_RNR)
1165 set_bit(CONN_RNR_SENT, &chan->conn_state);
1166
1167 if (control->super != L2CAP_SUPER_SREJ) {
1168 chan->last_acked_seq = control->reqseq;
1169 __clear_ack_timer(chan);
1170 }
1171
1172 BT_DBG("reqseq %d, final %d, poll %d, super %d", control->reqseq,
1173 control->final, control->poll, control->super);
1174
1175 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
1176 control_field = __pack_extended_control(control);
1177 else
1178 control_field = __pack_enhanced_control(control);
1179
1180 skb = l2cap_create_sframe_pdu(chan, control_field);
1181 if (!IS_ERR(skb))
1182 l2cap_do_send(chan, skb);
1183}
1184
1185static void l2cap_send_rr_or_rnr(struct l2cap_chan *chan, bool poll)
1186{
1187 struct l2cap_ctrl control;
1188
1189 BT_DBG("chan %p, poll %d", chan, poll);
1190
1191 memset(&control, 0, sizeof(control));
1192 control.sframe = 1;
1193 control.poll = poll;
1194
1195 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state))
1196 control.super = L2CAP_SUPER_RNR;
1197 else
1198 control.super = L2CAP_SUPER_RR;
1199
1200 control.reqseq = chan->buffer_seq;
1201 l2cap_send_sframe(chan, &control);
1202}
1203
1204static inline int __l2cap_no_conn_pending(struct l2cap_chan *chan)
1205{
1206 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED)
1207 return true;
1208
1209 return !test_bit(CONF_CONNECT_PEND, &chan->conf_state);
1210}
1211
1212static bool __amp_capable(struct l2cap_chan *chan)
1213{
1214 struct l2cap_conn *conn = chan->conn;
1215 struct hci_dev *hdev;
1216 bool amp_available = false;
1217
1218 if (!(conn->local_fixed_chan & L2CAP_FC_A2MP))
1219 return false;
1220
1221 if (!(conn->remote_fixed_chan & L2CAP_FC_A2MP))
1222 return false;
1223
1224 read_lock(&hci_dev_list_lock);
1225 list_for_each_entry(hdev, &hci_dev_list, list) {
1226 if (hdev->amp_type != AMP_TYPE_BREDR &&
1227 test_bit(HCI_UP, &hdev->flags)) {
1228 amp_available = true;
1229 break;
1230 }
1231 }
1232 read_unlock(&hci_dev_list_lock);
1233
1234 if (chan->chan_policy == BT_CHANNEL_POLICY_AMP_PREFERRED)
1235 return amp_available;
1236
1237 return false;
1238}
1239
1240static bool l2cap_check_efs(struct l2cap_chan *chan)
1241{
1242 /* Check EFS parameters */
1243 return true;
1244}
1245
1246void l2cap_send_conn_req(struct l2cap_chan *chan)
1247{
1248 struct l2cap_conn *conn = chan->conn;
1249 struct l2cap_conn_req req;
1250
1251 req.scid = cpu_to_le16(chan->scid);
1252 req.psm = chan->psm;
1253
1254 chan->ident = l2cap_get_ident(conn);
1255
1256 set_bit(CONF_CONNECT_PEND, &chan->conf_state);
1257
1258 l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_REQ, sizeof(req), &req);
1259}
1260
1261static void l2cap_send_create_chan_req(struct l2cap_chan *chan, u8 amp_id)
1262{
1263 struct l2cap_create_chan_req req;
1264 req.scid = cpu_to_le16(chan->scid);
1265 req.psm = chan->psm;
1266 req.amp_id = amp_id;
1267
1268 chan->ident = l2cap_get_ident(chan->conn);
1269
1270 l2cap_send_cmd(chan->conn, chan->ident, L2CAP_CREATE_CHAN_REQ,
1271 sizeof(req), &req);
1272}
1273
1274static void l2cap_move_setup(struct l2cap_chan *chan)
1275{
1276 struct sk_buff *skb;
1277
1278 BT_DBG("chan %p", chan);
1279
1280 if (chan->mode != L2CAP_MODE_ERTM)
1281 return;
1282
1283 __clear_retrans_timer(chan);
1284 __clear_monitor_timer(chan);
1285 __clear_ack_timer(chan);
1286
1287 chan->retry_count = 0;
1288 skb_queue_walk(&chan->tx_q, skb) {
1289 if (bt_cb(skb)->l2cap.retries)
1290 bt_cb(skb)->l2cap.retries = 1;
1291 else
1292 break;
1293 }
1294
1295 chan->expected_tx_seq = chan->buffer_seq;
1296
1297 clear_bit(CONN_REJ_ACT, &chan->conn_state);
1298 clear_bit(CONN_SREJ_ACT, &chan->conn_state);
1299 l2cap_seq_list_clear(&chan->retrans_list);
1300 l2cap_seq_list_clear(&chan->srej_list);
1301 skb_queue_purge(&chan->srej_q);
1302
1303 chan->tx_state = L2CAP_TX_STATE_XMIT;
1304 chan->rx_state = L2CAP_RX_STATE_MOVE;
1305
1306 set_bit(CONN_REMOTE_BUSY, &chan->conn_state);
1307}
1308
1309static void l2cap_move_done(struct l2cap_chan *chan)
1310{
1311 u8 move_role = chan->move_role;
1312 BT_DBG("chan %p", chan);
1313
1314 chan->move_state = L2CAP_MOVE_STABLE;
1315 chan->move_role = L2CAP_MOVE_ROLE_NONE;
1316
1317 if (chan->mode != L2CAP_MODE_ERTM)
1318 return;
1319
1320 switch (move_role) {
1321 case L2CAP_MOVE_ROLE_INITIATOR:
1322 l2cap_tx(chan, NULL, NULL, L2CAP_EV_EXPLICIT_POLL);
1323 chan->rx_state = L2CAP_RX_STATE_WAIT_F;
1324 break;
1325 case L2CAP_MOVE_ROLE_RESPONDER:
1326 chan->rx_state = L2CAP_RX_STATE_WAIT_P;
1327 break;
1328 }
1329}
1330
1331static void l2cap_chan_ready(struct l2cap_chan *chan)
1332{
1333 /* The channel may have already been flagged as connected in
1334 * case of receiving data before the L2CAP info req/rsp
1335 * procedure is complete.
1336 */
1337 if (chan->state == BT_CONNECTED)
1338 return;
1339
1340 /* This clears all conf flags, including CONF_NOT_COMPLETE */
1341 chan->conf_state = 0;
1342 __clear_chan_timer(chan);
1343
1344 switch (chan->mode) {
1345 case L2CAP_MODE_LE_FLOWCTL:
1346 case L2CAP_MODE_EXT_FLOWCTL:
1347 if (!chan->tx_credits)
1348 chan->ops->suspend(chan);
1349 break;
1350 }
1351
1352 chan->state = BT_CONNECTED;
1353
1354 chan->ops->ready(chan);
1355}
1356
1357static void l2cap_le_connect(struct l2cap_chan *chan)
1358{
1359 struct l2cap_conn *conn = chan->conn;
1360 struct l2cap_le_conn_req req;
1361
1362 if (test_and_set_bit(FLAG_LE_CONN_REQ_SENT, &chan->flags))
1363 return;
1364
1365 if (!chan->imtu)
1366 chan->imtu = chan->conn->mtu;
1367
1368 l2cap_le_flowctl_init(chan, 0);
1369
1370 req.psm = chan->psm;
1371 req.scid = cpu_to_le16(chan->scid);
1372 req.mtu = cpu_to_le16(chan->imtu);
1373 req.mps = cpu_to_le16(chan->mps);
1374 req.credits = cpu_to_le16(chan->rx_credits);
1375
1376 chan->ident = l2cap_get_ident(conn);
1377
1378 l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CONN_REQ,
1379 sizeof(req), &req);
1380}
1381
1382struct l2cap_ecred_conn_data {
1383 struct {
1384 struct l2cap_ecred_conn_req req;
1385 __le16 scid[5];
1386 } __packed pdu;
1387 struct l2cap_chan *chan;
1388 struct pid *pid;
1389 int count;
1390};
1391
1392static void l2cap_ecred_defer_connect(struct l2cap_chan *chan, void *data)
1393{
1394 struct l2cap_ecred_conn_data *conn = data;
1395 struct pid *pid;
1396
1397 if (chan == conn->chan)
1398 return;
1399
1400 if (!test_and_clear_bit(FLAG_DEFER_SETUP, &chan->flags))
1401 return;
1402
1403 pid = chan->ops->get_peer_pid(chan);
1404
1405 /* Only add deferred channels with the same PID/PSM */
1406 if (conn->pid != pid || chan->psm != conn->chan->psm || chan->ident ||
1407 chan->mode != L2CAP_MODE_EXT_FLOWCTL || chan->state != BT_CONNECT)
1408 return;
1409
1410 if (test_and_set_bit(FLAG_ECRED_CONN_REQ_SENT, &chan->flags))
1411 return;
1412
1413 l2cap_ecred_init(chan, 0);
1414
1415 /* Set the same ident so we can match on the rsp */
1416 chan->ident = conn->chan->ident;
1417
1418 /* Include all channels deferred */
1419 conn->pdu.scid[conn->count] = cpu_to_le16(chan->scid);
1420
1421 conn->count++;
1422}
1423
1424static void l2cap_ecred_connect(struct l2cap_chan *chan)
1425{
1426 struct l2cap_conn *conn = chan->conn;
1427 struct l2cap_ecred_conn_data data;
1428
1429 if (test_bit(FLAG_DEFER_SETUP, &chan->flags))
1430 return;
1431
1432 if (test_and_set_bit(FLAG_ECRED_CONN_REQ_SENT, &chan->flags))
1433 return;
1434
1435 l2cap_ecred_init(chan, 0);
1436
1437 data.pdu.req.psm = chan->psm;
1438 data.pdu.req.mtu = cpu_to_le16(chan->imtu);
1439 data.pdu.req.mps = cpu_to_le16(chan->mps);
1440 data.pdu.req.credits = cpu_to_le16(chan->rx_credits);
1441 data.pdu.scid[0] = cpu_to_le16(chan->scid);
1442
1443 chan->ident = l2cap_get_ident(conn);
1444 data.pid = chan->ops->get_peer_pid(chan);
1445
1446 data.count = 1;
1447 data.chan = chan;
1448 data.pid = chan->ops->get_peer_pid(chan);
1449
1450 __l2cap_chan_list(conn, l2cap_ecred_defer_connect, &data);
1451
1452 l2cap_send_cmd(conn, chan->ident, L2CAP_ECRED_CONN_REQ,
1453 sizeof(data.pdu.req) + data.count * sizeof(__le16),
1454 &data.pdu);
1455}
1456
1457static void l2cap_le_start(struct l2cap_chan *chan)
1458{
1459 struct l2cap_conn *conn = chan->conn;
1460
1461 if (!smp_conn_security(conn->hcon, chan->sec_level))
1462 return;
1463
1464 if (!chan->psm) {
1465 l2cap_chan_ready(chan);
1466 return;
1467 }
1468
1469 if (chan->state == BT_CONNECT) {
1470 if (chan->mode == L2CAP_MODE_EXT_FLOWCTL)
1471 l2cap_ecred_connect(chan);
1472 else
1473 l2cap_le_connect(chan);
1474 }
1475}
1476
1477static void l2cap_start_connection(struct l2cap_chan *chan)
1478{
1479 if (__amp_capable(chan)) {
1480 BT_DBG("chan %p AMP capable: discover AMPs", chan);
1481 a2mp_discover_amp(chan);
1482 } else if (chan->conn->hcon->type == LE_LINK) {
1483 l2cap_le_start(chan);
1484 } else {
1485 l2cap_send_conn_req(chan);
1486 }
1487}
1488
1489static void l2cap_request_info(struct l2cap_conn *conn)
1490{
1491 struct l2cap_info_req req;
1492
1493 if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT)
1494 return;
1495
1496 req.type = cpu_to_le16(L2CAP_IT_FEAT_MASK);
1497
1498 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_SENT;
1499 conn->info_ident = l2cap_get_ident(conn);
1500
1501 schedule_delayed_work(&conn->info_timer, L2CAP_INFO_TIMEOUT);
1502
1503 l2cap_send_cmd(conn, conn->info_ident, L2CAP_INFO_REQ,
1504 sizeof(req), &req);
1505}
1506
1507static bool l2cap_check_enc_key_size(struct hci_conn *hcon)
1508{
1509 /* The minimum encryption key size needs to be enforced by the
1510 * host stack before establishing any L2CAP connections. The
1511 * specification in theory allows a minimum of 1, but to align
1512 * BR/EDR and LE transports, a minimum of 7 is chosen.
1513 *
1514 * This check might also be called for unencrypted connections
1515 * that have no key size requirements. Ensure that the link is
1516 * actually encrypted before enforcing a key size.
1517 */
1518 return (!test_bit(HCI_CONN_ENCRYPT, &hcon->flags) ||
1519 hcon->enc_key_size >= hcon->hdev->min_enc_key_size);
1520}
1521
1522static void l2cap_do_start(struct l2cap_chan *chan)
1523{
1524 struct l2cap_conn *conn = chan->conn;
1525
1526 if (conn->hcon->type == LE_LINK) {
1527 l2cap_le_start(chan);
1528 return;
1529 }
1530
1531 if (!(conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT)) {
1532 l2cap_request_info(conn);
1533 return;
1534 }
1535
1536 if (!(conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE))
1537 return;
1538
1539 if (!l2cap_chan_check_security(chan, true) ||
1540 !__l2cap_no_conn_pending(chan))
1541 return;
1542
1543 if (l2cap_check_enc_key_size(conn->hcon))
1544 l2cap_start_connection(chan);
1545 else
1546 __set_chan_timer(chan, L2CAP_DISC_TIMEOUT);
1547}
1548
1549static inline int l2cap_mode_supported(__u8 mode, __u32 feat_mask)
1550{
1551 u32 local_feat_mask = l2cap_feat_mask;
1552 if (!disable_ertm)
1553 local_feat_mask |= L2CAP_FEAT_ERTM | L2CAP_FEAT_STREAMING;
1554
1555 switch (mode) {
1556 case L2CAP_MODE_ERTM:
1557 return L2CAP_FEAT_ERTM & feat_mask & local_feat_mask;
1558 case L2CAP_MODE_STREAMING:
1559 return L2CAP_FEAT_STREAMING & feat_mask & local_feat_mask;
1560 default:
1561 return 0x00;
1562 }
1563}
1564
1565static void l2cap_send_disconn_req(struct l2cap_chan *chan, int err)
1566{
1567 struct l2cap_conn *conn = chan->conn;
1568 struct l2cap_disconn_req req;
1569
1570 if (!conn)
1571 return;
1572
1573 if (chan->mode == L2CAP_MODE_ERTM && chan->state == BT_CONNECTED) {
1574 __clear_retrans_timer(chan);
1575 __clear_monitor_timer(chan);
1576 __clear_ack_timer(chan);
1577 }
1578
1579 if (chan->scid == L2CAP_CID_A2MP) {
1580 l2cap_state_change(chan, BT_DISCONN);
1581 return;
1582 }
1583
1584 req.dcid = cpu_to_le16(chan->dcid);
1585 req.scid = cpu_to_le16(chan->scid);
1586 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_DISCONN_REQ,
1587 sizeof(req), &req);
1588
1589 l2cap_state_change_and_error(chan, BT_DISCONN, err);
1590}
1591
1592/* ---- L2CAP connections ---- */
1593static void l2cap_conn_start(struct l2cap_conn *conn)
1594{
1595 struct l2cap_chan *chan, *tmp;
1596
1597 BT_DBG("conn %p", conn);
1598
1599 mutex_lock(&conn->chan_lock);
1600
1601 list_for_each_entry_safe(chan, tmp, &conn->chan_l, list) {
1602 l2cap_chan_lock(chan);
1603
1604 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) {
1605 l2cap_chan_ready(chan);
1606 l2cap_chan_unlock(chan);
1607 continue;
1608 }
1609
1610 if (chan->state == BT_CONNECT) {
1611 if (!l2cap_chan_check_security(chan, true) ||
1612 !__l2cap_no_conn_pending(chan)) {
1613 l2cap_chan_unlock(chan);
1614 continue;
1615 }
1616
1617 if (!l2cap_mode_supported(chan->mode, conn->feat_mask)
1618 && test_bit(CONF_STATE2_DEVICE,
1619 &chan->conf_state)) {
1620 l2cap_chan_close(chan, ECONNRESET);
1621 l2cap_chan_unlock(chan);
1622 continue;
1623 }
1624
1625 if (l2cap_check_enc_key_size(conn->hcon))
1626 l2cap_start_connection(chan);
1627 else
1628 l2cap_chan_close(chan, ECONNREFUSED);
1629
1630 } else if (chan->state == BT_CONNECT2) {
1631 struct l2cap_conn_rsp rsp;
1632 char buf[128];
1633 rsp.scid = cpu_to_le16(chan->dcid);
1634 rsp.dcid = cpu_to_le16(chan->scid);
1635
1636 if (l2cap_chan_check_security(chan, false)) {
1637 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) {
1638 rsp.result = cpu_to_le16(L2CAP_CR_PEND);
1639 rsp.status = cpu_to_le16(L2CAP_CS_AUTHOR_PEND);
1640 chan->ops->defer(chan);
1641
1642 } else {
1643 l2cap_state_change(chan, BT_CONFIG);
1644 rsp.result = cpu_to_le16(L2CAP_CR_SUCCESS);
1645 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
1646 }
1647 } else {
1648 rsp.result = cpu_to_le16(L2CAP_CR_PEND);
1649 rsp.status = cpu_to_le16(L2CAP_CS_AUTHEN_PEND);
1650 }
1651
1652 l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_RSP,
1653 sizeof(rsp), &rsp);
1654
1655 if (test_bit(CONF_REQ_SENT, &chan->conf_state) ||
1656 rsp.result != L2CAP_CR_SUCCESS) {
1657 l2cap_chan_unlock(chan);
1658 continue;
1659 }
1660
1661 set_bit(CONF_REQ_SENT, &chan->conf_state);
1662 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
1663 l2cap_build_conf_req(chan, buf, sizeof(buf)), buf);
1664 chan->num_conf_req++;
1665 }
1666
1667 l2cap_chan_unlock(chan);
1668 }
1669
1670 mutex_unlock(&conn->chan_lock);
1671}
1672
1673static void l2cap_le_conn_ready(struct l2cap_conn *conn)
1674{
1675 struct hci_conn *hcon = conn->hcon;
1676 struct hci_dev *hdev = hcon->hdev;
1677
1678 BT_DBG("%s conn %p", hdev->name, conn);
1679
1680 /* For outgoing pairing which doesn't necessarily have an
1681 * associated socket (e.g. mgmt_pair_device).
1682 */
1683 if (hcon->out)
1684 smp_conn_security(hcon, hcon->pending_sec_level);
1685
1686 /* For LE slave connections, make sure the connection interval
1687 * is in the range of the minium and maximum interval that has
1688 * been configured for this connection. If not, then trigger
1689 * the connection update procedure.
1690 */
1691 if (hcon->role == HCI_ROLE_SLAVE &&
1692 (hcon->le_conn_interval < hcon->le_conn_min_interval ||
1693 hcon->le_conn_interval > hcon->le_conn_max_interval)) {
1694 struct l2cap_conn_param_update_req req;
1695
1696 req.min = cpu_to_le16(hcon->le_conn_min_interval);
1697 req.max = cpu_to_le16(hcon->le_conn_max_interval);
1698 req.latency = cpu_to_le16(hcon->le_conn_latency);
1699 req.to_multiplier = cpu_to_le16(hcon->le_supv_timeout);
1700
1701 l2cap_send_cmd(conn, l2cap_get_ident(conn),
1702 L2CAP_CONN_PARAM_UPDATE_REQ, sizeof(req), &req);
1703 }
1704}
1705
1706static void l2cap_conn_ready(struct l2cap_conn *conn)
1707{
1708 struct l2cap_chan *chan;
1709 struct hci_conn *hcon = conn->hcon;
1710
1711 BT_DBG("conn %p", conn);
1712
1713 if (hcon->type == ACL_LINK)
1714 l2cap_request_info(conn);
1715
1716 mutex_lock(&conn->chan_lock);
1717
1718 list_for_each_entry(chan, &conn->chan_l, list) {
1719
1720 l2cap_chan_lock(chan);
1721
1722 if (chan->scid == L2CAP_CID_A2MP) {
1723 l2cap_chan_unlock(chan);
1724 continue;
1725 }
1726
1727 if (hcon->type == LE_LINK) {
1728 l2cap_le_start(chan);
1729 } else if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) {
1730 if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE)
1731 l2cap_chan_ready(chan);
1732 } else if (chan->state == BT_CONNECT) {
1733 l2cap_do_start(chan);
1734 }
1735
1736 l2cap_chan_unlock(chan);
1737 }
1738
1739 mutex_unlock(&conn->chan_lock);
1740
1741 if (hcon->type == LE_LINK)
1742 l2cap_le_conn_ready(conn);
1743
1744 queue_work(hcon->hdev->workqueue, &conn->pending_rx_work);
1745}
1746
1747/* Notify sockets that we cannot guaranty reliability anymore */
1748static void l2cap_conn_unreliable(struct l2cap_conn *conn, int err)
1749{
1750 struct l2cap_chan *chan;
1751
1752 BT_DBG("conn %p", conn);
1753
1754 mutex_lock(&conn->chan_lock);
1755
1756 list_for_each_entry(chan, &conn->chan_l, list) {
1757 if (test_bit(FLAG_FORCE_RELIABLE, &chan->flags))
1758 l2cap_chan_set_err(chan, err);
1759 }
1760
1761 mutex_unlock(&conn->chan_lock);
1762}
1763
1764static void l2cap_info_timeout(struct work_struct *work)
1765{
1766 struct l2cap_conn *conn = container_of(work, struct l2cap_conn,
1767 info_timer.work);
1768
1769 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
1770 conn->info_ident = 0;
1771
1772 l2cap_conn_start(conn);
1773}
1774
1775/*
1776 * l2cap_user
1777 * External modules can register l2cap_user objects on l2cap_conn. The ->probe
1778 * callback is called during registration. The ->remove callback is called
1779 * during unregistration.
1780 * An l2cap_user object can either be explicitly unregistered or when the
1781 * underlying l2cap_conn object is deleted. This guarantees that l2cap->hcon,
1782 * l2cap->hchan, .. are valid as long as the remove callback hasn't been called.
1783 * External modules must own a reference to the l2cap_conn object if they intend
1784 * to call l2cap_unregister_user(). The l2cap_conn object might get destroyed at
1785 * any time if they don't.
1786 */
1787
1788int l2cap_register_user(struct l2cap_conn *conn, struct l2cap_user *user)
1789{
1790 struct hci_dev *hdev = conn->hcon->hdev;
1791 int ret;
1792
1793 /* We need to check whether l2cap_conn is registered. If it is not, we
1794 * must not register the l2cap_user. l2cap_conn_del() is unregisters
1795 * l2cap_conn objects, but doesn't provide its own locking. Instead, it
1796 * relies on the parent hci_conn object to be locked. This itself relies
1797 * on the hci_dev object to be locked. So we must lock the hci device
1798 * here, too. */
1799
1800 hci_dev_lock(hdev);
1801
1802 if (!list_empty(&user->list)) {
1803 ret = -EINVAL;
1804 goto out_unlock;
1805 }
1806
1807 /* conn->hchan is NULL after l2cap_conn_del() was called */
1808 if (!conn->hchan) {
1809 ret = -ENODEV;
1810 goto out_unlock;
1811 }
1812
1813 ret = user->probe(conn, user);
1814 if (ret)
1815 goto out_unlock;
1816
1817 list_add(&user->list, &conn->users);
1818 ret = 0;
1819
1820out_unlock:
1821 hci_dev_unlock(hdev);
1822 return ret;
1823}
1824EXPORT_SYMBOL(l2cap_register_user);
1825
1826void l2cap_unregister_user(struct l2cap_conn *conn, struct l2cap_user *user)
1827{
1828 struct hci_dev *hdev = conn->hcon->hdev;
1829
1830 hci_dev_lock(hdev);
1831
1832 if (list_empty(&user->list))
1833 goto out_unlock;
1834
1835 list_del_init(&user->list);
1836 user->remove(conn, user);
1837
1838out_unlock:
1839 hci_dev_unlock(hdev);
1840}
1841EXPORT_SYMBOL(l2cap_unregister_user);
1842
1843static void l2cap_unregister_all_users(struct l2cap_conn *conn)
1844{
1845 struct l2cap_user *user;
1846
1847 while (!list_empty(&conn->users)) {
1848 user = list_first_entry(&conn->users, struct l2cap_user, list);
1849 list_del_init(&user->list);
1850 user->remove(conn, user);
1851 }
1852}
1853
1854static void l2cap_conn_del(struct hci_conn *hcon, int err)
1855{
1856 struct l2cap_conn *conn = hcon->l2cap_data;
1857 struct l2cap_chan *chan, *l;
1858
1859 if (!conn)
1860 return;
1861
1862 BT_DBG("hcon %p conn %p, err %d", hcon, conn, err);
1863
1864 kfree_skb(conn->rx_skb);
1865
1866 skb_queue_purge(&conn->pending_rx);
1867
1868 /* We can not call flush_work(&conn->pending_rx_work) here since we
1869 * might block if we are running on a worker from the same workqueue
1870 * pending_rx_work is waiting on.
1871 */
1872 if (work_pending(&conn->pending_rx_work))
1873 cancel_work_sync(&conn->pending_rx_work);
1874
1875 if (work_pending(&conn->id_addr_update_work))
1876 cancel_work_sync(&conn->id_addr_update_work);
1877
1878 l2cap_unregister_all_users(conn);
1879
1880 /* Force the connection to be immediately dropped */
1881 hcon->disc_timeout = 0;
1882
1883 mutex_lock(&conn->chan_lock);
1884
1885 /* Kill channels */
1886 list_for_each_entry_safe(chan, l, &conn->chan_l, list) {
1887 l2cap_chan_hold(chan);
1888 l2cap_chan_lock(chan);
1889
1890 l2cap_chan_del(chan, err);
1891
1892 chan->ops->close(chan);
1893
1894 l2cap_chan_unlock(chan);
1895 l2cap_chan_put(chan);
1896 }
1897
1898 mutex_unlock(&conn->chan_lock);
1899
1900 hci_chan_del(conn->hchan);
1901
1902 if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT)
1903 cancel_delayed_work_sync(&conn->info_timer);
1904
1905 hcon->l2cap_data = NULL;
1906 conn->hchan = NULL;
1907 l2cap_conn_put(conn);
1908}
1909
1910static void l2cap_conn_free(struct kref *ref)
1911{
1912 struct l2cap_conn *conn = container_of(ref, struct l2cap_conn, ref);
1913
1914 hci_conn_put(conn->hcon);
1915 kfree(conn);
1916}
1917
1918struct l2cap_conn *l2cap_conn_get(struct l2cap_conn *conn)
1919{
1920 kref_get(&conn->ref);
1921 return conn;
1922}
1923EXPORT_SYMBOL(l2cap_conn_get);
1924
1925void l2cap_conn_put(struct l2cap_conn *conn)
1926{
1927 kref_put(&conn->ref, l2cap_conn_free);
1928}
1929EXPORT_SYMBOL(l2cap_conn_put);
1930
1931/* ---- Socket interface ---- */
1932
1933/* Find socket with psm and source / destination bdaddr.
1934 * Returns closest match.
1935 */
1936static struct l2cap_chan *l2cap_global_chan_by_psm(int state, __le16 psm,
1937 bdaddr_t *src,
1938 bdaddr_t *dst,
1939 u8 link_type)
1940{
1941 struct l2cap_chan *c, *c1 = NULL;
1942
1943 read_lock(&chan_list_lock);
1944
1945 list_for_each_entry(c, &chan_list, global_l) {
1946 if (state && c->state != state)
1947 continue;
1948
1949 if (link_type == ACL_LINK && c->src_type != BDADDR_BREDR)
1950 continue;
1951
1952 if (link_type == LE_LINK && c->src_type == BDADDR_BREDR)
1953 continue;
1954
1955 if (c->psm == psm) {
1956 int src_match, dst_match;
1957 int src_any, dst_any;
1958
1959 /* Exact match. */
1960 src_match = !bacmp(&c->src, src);
1961 dst_match = !bacmp(&c->dst, dst);
1962 if (src_match && dst_match) {
1963 l2cap_chan_hold(c);
1964 read_unlock(&chan_list_lock);
1965 return c;
1966 }
1967
1968 /* Closest match */
1969 src_any = !bacmp(&c->src, BDADDR_ANY);
1970 dst_any = !bacmp(&c->dst, BDADDR_ANY);
1971 if ((src_match && dst_any) || (src_any && dst_match) ||
1972 (src_any && dst_any))
1973 c1 = c;
1974 }
1975 }
1976
1977 if (c1)
1978 l2cap_chan_hold(c1);
1979
1980 read_unlock(&chan_list_lock);
1981
1982 return c1;
1983}
1984
1985static void l2cap_monitor_timeout(struct work_struct *work)
1986{
1987 struct l2cap_chan *chan = container_of(work, struct l2cap_chan,
1988 monitor_timer.work);
1989
1990 BT_DBG("chan %p", chan);
1991
1992 l2cap_chan_lock(chan);
1993
1994 if (!chan->conn) {
1995 l2cap_chan_unlock(chan);
1996 l2cap_chan_put(chan);
1997 return;
1998 }
1999
2000 l2cap_tx(chan, NULL, NULL, L2CAP_EV_MONITOR_TO);
2001
2002 l2cap_chan_unlock(chan);
2003 l2cap_chan_put(chan);
2004}
2005
2006static void l2cap_retrans_timeout(struct work_struct *work)
2007{
2008 struct l2cap_chan *chan = container_of(work, struct l2cap_chan,
2009 retrans_timer.work);
2010
2011 BT_DBG("chan %p", chan);
2012
2013 l2cap_chan_lock(chan);
2014
2015 if (!chan->conn) {
2016 l2cap_chan_unlock(chan);
2017 l2cap_chan_put(chan);
2018 return;
2019 }
2020
2021 l2cap_tx(chan, NULL, NULL, L2CAP_EV_RETRANS_TO);
2022 l2cap_chan_unlock(chan);
2023 l2cap_chan_put(chan);
2024}
2025
2026static void l2cap_streaming_send(struct l2cap_chan *chan,
2027 struct sk_buff_head *skbs)
2028{
2029 struct sk_buff *skb;
2030 struct l2cap_ctrl *control;
2031
2032 BT_DBG("chan %p, skbs %p", chan, skbs);
2033
2034 if (__chan_is_moving(chan))
2035 return;
2036
2037 skb_queue_splice_tail_init(skbs, &chan->tx_q);
2038
2039 while (!skb_queue_empty(&chan->tx_q)) {
2040
2041 skb = skb_dequeue(&chan->tx_q);
2042
2043 bt_cb(skb)->l2cap.retries = 1;
2044 control = &bt_cb(skb)->l2cap;
2045
2046 control->reqseq = 0;
2047 control->txseq = chan->next_tx_seq;
2048
2049 __pack_control(chan, control, skb);
2050
2051 if (chan->fcs == L2CAP_FCS_CRC16) {
2052 u16 fcs = crc16(0, (u8 *) skb->data, skb->len);
2053 put_unaligned_le16(fcs, skb_put(skb, L2CAP_FCS_SIZE));
2054 }
2055
2056 l2cap_do_send(chan, skb);
2057
2058 BT_DBG("Sent txseq %u", control->txseq);
2059
2060 chan->next_tx_seq = __next_seq(chan, chan->next_tx_seq);
2061 chan->frames_sent++;
2062 }
2063}
2064
2065static int l2cap_ertm_send(struct l2cap_chan *chan)
2066{
2067 struct sk_buff *skb, *tx_skb;
2068 struct l2cap_ctrl *control;
2069 int sent = 0;
2070
2071 BT_DBG("chan %p", chan);
2072
2073 if (chan->state != BT_CONNECTED)
2074 return -ENOTCONN;
2075
2076 if (test_bit(CONN_REMOTE_BUSY, &chan->conn_state))
2077 return 0;
2078
2079 if (__chan_is_moving(chan))
2080 return 0;
2081
2082 while (chan->tx_send_head &&
2083 chan->unacked_frames < chan->remote_tx_win &&
2084 chan->tx_state == L2CAP_TX_STATE_XMIT) {
2085
2086 skb = chan->tx_send_head;
2087
2088 bt_cb(skb)->l2cap.retries = 1;
2089 control = &bt_cb(skb)->l2cap;
2090
2091 if (test_and_clear_bit(CONN_SEND_FBIT, &chan->conn_state))
2092 control->final = 1;
2093
2094 control->reqseq = chan->buffer_seq;
2095 chan->last_acked_seq = chan->buffer_seq;
2096 control->txseq = chan->next_tx_seq;
2097
2098 __pack_control(chan, control, skb);
2099
2100 if (chan->fcs == L2CAP_FCS_CRC16) {
2101 u16 fcs = crc16(0, (u8 *) skb->data, skb->len);
2102 put_unaligned_le16(fcs, skb_put(skb, L2CAP_FCS_SIZE));
2103 }
2104
2105 /* Clone after data has been modified. Data is assumed to be
2106 read-only (for locking purposes) on cloned sk_buffs.
2107 */
2108 tx_skb = skb_clone(skb, GFP_KERNEL);
2109
2110 if (!tx_skb)
2111 break;
2112
2113 __set_retrans_timer(chan);
2114
2115 chan->next_tx_seq = __next_seq(chan, chan->next_tx_seq);
2116 chan->unacked_frames++;
2117 chan->frames_sent++;
2118 sent++;
2119
2120 if (skb_queue_is_last(&chan->tx_q, skb))
2121 chan->tx_send_head = NULL;
2122 else
2123 chan->tx_send_head = skb_queue_next(&chan->tx_q, skb);
2124
2125 l2cap_do_send(chan, tx_skb);
2126 BT_DBG("Sent txseq %u", control->txseq);
2127 }
2128
2129 BT_DBG("Sent %d, %u unacked, %u in ERTM queue", sent,
2130 chan->unacked_frames, skb_queue_len(&chan->tx_q));
2131
2132 return sent;
2133}
2134
2135static void l2cap_ertm_resend(struct l2cap_chan *chan)
2136{
2137 struct l2cap_ctrl control;
2138 struct sk_buff *skb;
2139 struct sk_buff *tx_skb;
2140 u16 seq;
2141
2142 BT_DBG("chan %p", chan);
2143
2144 if (test_bit(CONN_REMOTE_BUSY, &chan->conn_state))
2145 return;
2146
2147 if (__chan_is_moving(chan))
2148 return;
2149
2150 while (chan->retrans_list.head != L2CAP_SEQ_LIST_CLEAR) {
2151 seq = l2cap_seq_list_pop(&chan->retrans_list);
2152
2153 skb = l2cap_ertm_seq_in_queue(&chan->tx_q, seq);
2154 if (!skb) {
2155 BT_DBG("Error: Can't retransmit seq %d, frame missing",
2156 seq);
2157 continue;
2158 }
2159
2160 bt_cb(skb)->l2cap.retries++;
2161 control = bt_cb(skb)->l2cap;
2162
2163 if (chan->max_tx != 0 &&
2164 bt_cb(skb)->l2cap.retries > chan->max_tx) {
2165 BT_DBG("Retry limit exceeded (%d)", chan->max_tx);
2166 l2cap_send_disconn_req(chan, ECONNRESET);
2167 l2cap_seq_list_clear(&chan->retrans_list);
2168 break;
2169 }
2170
2171 control.reqseq = chan->buffer_seq;
2172 if (test_and_clear_bit(CONN_SEND_FBIT, &chan->conn_state))
2173 control.final = 1;
2174 else
2175 control.final = 0;
2176
2177 if (skb_cloned(skb)) {
2178 /* Cloned sk_buffs are read-only, so we need a
2179 * writeable copy
2180 */
2181 tx_skb = skb_copy(skb, GFP_KERNEL);
2182 } else {
2183 tx_skb = skb_clone(skb, GFP_KERNEL);
2184 }
2185
2186 if (!tx_skb) {
2187 l2cap_seq_list_clear(&chan->retrans_list);
2188 break;
2189 }
2190
2191 /* Update skb contents */
2192 if (test_bit(FLAG_EXT_CTRL, &chan->flags)) {
2193 put_unaligned_le32(__pack_extended_control(&control),
2194 tx_skb->data + L2CAP_HDR_SIZE);
2195 } else {
2196 put_unaligned_le16(__pack_enhanced_control(&control),
2197 tx_skb->data + L2CAP_HDR_SIZE);
2198 }
2199
2200 /* Update FCS */
2201 if (chan->fcs == L2CAP_FCS_CRC16) {
2202 u16 fcs = crc16(0, (u8 *) tx_skb->data,
2203 tx_skb->len - L2CAP_FCS_SIZE);
2204 put_unaligned_le16(fcs, skb_tail_pointer(tx_skb) -
2205 L2CAP_FCS_SIZE);
2206 }
2207
2208 l2cap_do_send(chan, tx_skb);
2209
2210 BT_DBG("Resent txseq %d", control.txseq);
2211
2212 chan->last_acked_seq = chan->buffer_seq;
2213 }
2214}
2215
2216static void l2cap_retransmit(struct l2cap_chan *chan,
2217 struct l2cap_ctrl *control)
2218{
2219 BT_DBG("chan %p, control %p", chan, control);
2220
2221 l2cap_seq_list_append(&chan->retrans_list, control->reqseq);
2222 l2cap_ertm_resend(chan);
2223}
2224
2225static void l2cap_retransmit_all(struct l2cap_chan *chan,
2226 struct l2cap_ctrl *control)
2227{
2228 struct sk_buff *skb;
2229
2230 BT_DBG("chan %p, control %p", chan, control);
2231
2232 if (control->poll)
2233 set_bit(CONN_SEND_FBIT, &chan->conn_state);
2234
2235 l2cap_seq_list_clear(&chan->retrans_list);
2236
2237 if (test_bit(CONN_REMOTE_BUSY, &chan->conn_state))
2238 return;
2239
2240 if (chan->unacked_frames) {
2241 skb_queue_walk(&chan->tx_q, skb) {
2242 if (bt_cb(skb)->l2cap.txseq == control->reqseq ||
2243 skb == chan->tx_send_head)
2244 break;
2245 }
2246
2247 skb_queue_walk_from(&chan->tx_q, skb) {
2248 if (skb == chan->tx_send_head)
2249 break;
2250
2251 l2cap_seq_list_append(&chan->retrans_list,
2252 bt_cb(skb)->l2cap.txseq);
2253 }
2254
2255 l2cap_ertm_resend(chan);
2256 }
2257}
2258
2259static void l2cap_send_ack(struct l2cap_chan *chan)
2260{
2261 struct l2cap_ctrl control;
2262 u16 frames_to_ack = __seq_offset(chan, chan->buffer_seq,
2263 chan->last_acked_seq);
2264 int threshold;
2265
2266 BT_DBG("chan %p last_acked_seq %d buffer_seq %d",
2267 chan, chan->last_acked_seq, chan->buffer_seq);
2268
2269 memset(&control, 0, sizeof(control));
2270 control.sframe = 1;
2271
2272 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state) &&
2273 chan->rx_state == L2CAP_RX_STATE_RECV) {
2274 __clear_ack_timer(chan);
2275 control.super = L2CAP_SUPER_RNR;
2276 control.reqseq = chan->buffer_seq;
2277 l2cap_send_sframe(chan, &control);
2278 } else {
2279 if (!test_bit(CONN_REMOTE_BUSY, &chan->conn_state)) {
2280 l2cap_ertm_send(chan);
2281 /* If any i-frames were sent, they included an ack */
2282 if (chan->buffer_seq == chan->last_acked_seq)
2283 frames_to_ack = 0;
2284 }
2285
2286 /* Ack now if the window is 3/4ths full.
2287 * Calculate without mul or div
2288 */
2289 threshold = chan->ack_win;
2290 threshold += threshold << 1;
2291 threshold >>= 2;
2292
2293 BT_DBG("frames_to_ack %u, threshold %d", frames_to_ack,
2294 threshold);
2295
2296 if (frames_to_ack >= threshold) {
2297 __clear_ack_timer(chan);
2298 control.super = L2CAP_SUPER_RR;
2299 control.reqseq = chan->buffer_seq;
2300 l2cap_send_sframe(chan, &control);
2301 frames_to_ack = 0;
2302 }
2303
2304 if (frames_to_ack)
2305 __set_ack_timer(chan);
2306 }
2307}
2308
2309static inline int l2cap_skbuff_fromiovec(struct l2cap_chan *chan,
2310 struct msghdr *msg, int len,
2311 int count, struct sk_buff *skb)
2312{
2313 struct l2cap_conn *conn = chan->conn;
2314 struct sk_buff **frag;
2315 int sent = 0;
2316
2317 if (!copy_from_iter_full(skb_put(skb, count), count, &msg->msg_iter))
2318 return -EFAULT;
2319
2320 sent += count;
2321 len -= count;
2322
2323 /* Continuation fragments (no L2CAP header) */
2324 frag = &skb_shinfo(skb)->frag_list;
2325 while (len) {
2326 struct sk_buff *tmp;
2327
2328 count = min_t(unsigned int, conn->mtu, len);
2329
2330 tmp = chan->ops->alloc_skb(chan, 0, count,
2331 msg->msg_flags & MSG_DONTWAIT);
2332 if (IS_ERR(tmp))
2333 return PTR_ERR(tmp);
2334
2335 *frag = tmp;
2336
2337 if (!copy_from_iter_full(skb_put(*frag, count), count,
2338 &msg->msg_iter))
2339 return -EFAULT;
2340
2341 sent += count;
2342 len -= count;
2343
2344 skb->len += (*frag)->len;
2345 skb->data_len += (*frag)->len;
2346
2347 frag = &(*frag)->next;
2348 }
2349
2350 return sent;
2351}
2352
2353static struct sk_buff *l2cap_create_connless_pdu(struct l2cap_chan *chan,
2354 struct msghdr *msg, size_t len)
2355{
2356 struct l2cap_conn *conn = chan->conn;
2357 struct sk_buff *skb;
2358 int err, count, hlen = L2CAP_HDR_SIZE + L2CAP_PSMLEN_SIZE;
2359 struct l2cap_hdr *lh;
2360
2361 BT_DBG("chan %p psm 0x%2.2x len %zu", chan,
2362 __le16_to_cpu(chan->psm), len);
2363
2364 count = min_t(unsigned int, (conn->mtu - hlen), len);
2365
2366 skb = chan->ops->alloc_skb(chan, hlen, count,
2367 msg->msg_flags & MSG_DONTWAIT);
2368 if (IS_ERR(skb))
2369 return skb;
2370
2371 /* Create L2CAP header */
2372 lh = skb_put(skb, L2CAP_HDR_SIZE);
2373 lh->cid = cpu_to_le16(chan->dcid);
2374 lh->len = cpu_to_le16(len + L2CAP_PSMLEN_SIZE);
2375 put_unaligned(chan->psm, (__le16 *) skb_put(skb, L2CAP_PSMLEN_SIZE));
2376
2377 err = l2cap_skbuff_fromiovec(chan, msg, len, count, skb);
2378 if (unlikely(err < 0)) {
2379 kfree_skb(skb);
2380 return ERR_PTR(err);
2381 }
2382 return skb;
2383}
2384
2385static struct sk_buff *l2cap_create_basic_pdu(struct l2cap_chan *chan,
2386 struct msghdr *msg, size_t len)
2387{
2388 struct l2cap_conn *conn = chan->conn;
2389 struct sk_buff *skb;
2390 int err, count;
2391 struct l2cap_hdr *lh;
2392
2393 BT_DBG("chan %p len %zu", chan, len);
2394
2395 count = min_t(unsigned int, (conn->mtu - L2CAP_HDR_SIZE), len);
2396
2397 skb = chan->ops->alloc_skb(chan, L2CAP_HDR_SIZE, count,
2398 msg->msg_flags & MSG_DONTWAIT);
2399 if (IS_ERR(skb))
2400 return skb;
2401
2402 /* Create L2CAP header */
2403 lh = skb_put(skb, L2CAP_HDR_SIZE);
2404 lh->cid = cpu_to_le16(chan->dcid);
2405 lh->len = cpu_to_le16(len);
2406
2407 err = l2cap_skbuff_fromiovec(chan, msg, len, count, skb);
2408 if (unlikely(err < 0)) {
2409 kfree_skb(skb);
2410 return ERR_PTR(err);
2411 }
2412 return skb;
2413}
2414
2415static struct sk_buff *l2cap_create_iframe_pdu(struct l2cap_chan *chan,
2416 struct msghdr *msg, size_t len,
2417 u16 sdulen)
2418{
2419 struct l2cap_conn *conn = chan->conn;
2420 struct sk_buff *skb;
2421 int err, count, hlen;
2422 struct l2cap_hdr *lh;
2423
2424 BT_DBG("chan %p len %zu", chan, len);
2425
2426 if (!conn)
2427 return ERR_PTR(-ENOTCONN);
2428
2429 hlen = __ertm_hdr_size(chan);
2430
2431 if (sdulen)
2432 hlen += L2CAP_SDULEN_SIZE;
2433
2434 if (chan->fcs == L2CAP_FCS_CRC16)
2435 hlen += L2CAP_FCS_SIZE;
2436
2437 count = min_t(unsigned int, (conn->mtu - hlen), len);
2438
2439 skb = chan->ops->alloc_skb(chan, hlen, count,
2440 msg->msg_flags & MSG_DONTWAIT);
2441 if (IS_ERR(skb))
2442 return skb;
2443
2444 /* Create L2CAP header */
2445 lh = skb_put(skb, L2CAP_HDR_SIZE);
2446 lh->cid = cpu_to_le16(chan->dcid);
2447 lh->len = cpu_to_le16(len + (hlen - L2CAP_HDR_SIZE));
2448
2449 /* Control header is populated later */
2450 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
2451 put_unaligned_le32(0, skb_put(skb, L2CAP_EXT_CTRL_SIZE));
2452 else
2453 put_unaligned_le16(0, skb_put(skb, L2CAP_ENH_CTRL_SIZE));
2454
2455 if (sdulen)
2456 put_unaligned_le16(sdulen, skb_put(skb, L2CAP_SDULEN_SIZE));
2457
2458 err = l2cap_skbuff_fromiovec(chan, msg, len, count, skb);
2459 if (unlikely(err < 0)) {
2460 kfree_skb(skb);
2461 return ERR_PTR(err);
2462 }
2463
2464 bt_cb(skb)->l2cap.fcs = chan->fcs;
2465 bt_cb(skb)->l2cap.retries = 0;
2466 return skb;
2467}
2468
2469static int l2cap_segment_sdu(struct l2cap_chan *chan,
2470 struct sk_buff_head *seg_queue,
2471 struct msghdr *msg, size_t len)
2472{
2473 struct sk_buff *skb;
2474 u16 sdu_len;
2475 size_t pdu_len;
2476 u8 sar;
2477
2478 BT_DBG("chan %p, msg %p, len %zu", chan, msg, len);
2479
2480 /* It is critical that ERTM PDUs fit in a single HCI fragment,
2481 * so fragmented skbs are not used. The HCI layer's handling
2482 * of fragmented skbs is not compatible with ERTM's queueing.
2483 */
2484
2485 /* PDU size is derived from the HCI MTU */
2486 pdu_len = chan->conn->mtu;
2487
2488 /* Constrain PDU size for BR/EDR connections */
2489 if (!chan->hs_hcon)
2490 pdu_len = min_t(size_t, pdu_len, L2CAP_BREDR_MAX_PAYLOAD);
2491
2492 /* Adjust for largest possible L2CAP overhead. */
2493 if (chan->fcs)
2494 pdu_len -= L2CAP_FCS_SIZE;
2495
2496 pdu_len -= __ertm_hdr_size(chan);
2497
2498 /* Remote device may have requested smaller PDUs */
2499 pdu_len = min_t(size_t, pdu_len, chan->remote_mps);
2500
2501 if (len <= pdu_len) {
2502 sar = L2CAP_SAR_UNSEGMENTED;
2503 sdu_len = 0;
2504 pdu_len = len;
2505 } else {
2506 sar = L2CAP_SAR_START;
2507 sdu_len = len;
2508 }
2509
2510 while (len > 0) {
2511 skb = l2cap_create_iframe_pdu(chan, msg, pdu_len, sdu_len);
2512
2513 if (IS_ERR(skb)) {
2514 __skb_queue_purge(seg_queue);
2515 return PTR_ERR(skb);
2516 }
2517
2518 bt_cb(skb)->l2cap.sar = sar;
2519 __skb_queue_tail(seg_queue, skb);
2520
2521 len -= pdu_len;
2522 if (sdu_len)
2523 sdu_len = 0;
2524
2525 if (len <= pdu_len) {
2526 sar = L2CAP_SAR_END;
2527 pdu_len = len;
2528 } else {
2529 sar = L2CAP_SAR_CONTINUE;
2530 }
2531 }
2532
2533 return 0;
2534}
2535
2536static struct sk_buff *l2cap_create_le_flowctl_pdu(struct l2cap_chan *chan,
2537 struct msghdr *msg,
2538 size_t len, u16 sdulen)
2539{
2540 struct l2cap_conn *conn = chan->conn;
2541 struct sk_buff *skb;
2542 int err, count, hlen;
2543 struct l2cap_hdr *lh;
2544
2545 BT_DBG("chan %p len %zu", chan, len);
2546
2547 if (!conn)
2548 return ERR_PTR(-ENOTCONN);
2549
2550 hlen = L2CAP_HDR_SIZE;
2551
2552 if (sdulen)
2553 hlen += L2CAP_SDULEN_SIZE;
2554
2555 count = min_t(unsigned int, (conn->mtu - hlen), len);
2556
2557 skb = chan->ops->alloc_skb(chan, hlen, count,
2558 msg->msg_flags & MSG_DONTWAIT);
2559 if (IS_ERR(skb))
2560 return skb;
2561
2562 /* Create L2CAP header */
2563 lh = skb_put(skb, L2CAP_HDR_SIZE);
2564 lh->cid = cpu_to_le16(chan->dcid);
2565 lh->len = cpu_to_le16(len + (hlen - L2CAP_HDR_SIZE));
2566
2567 if (sdulen)
2568 put_unaligned_le16(sdulen, skb_put(skb, L2CAP_SDULEN_SIZE));
2569
2570 err = l2cap_skbuff_fromiovec(chan, msg, len, count, skb);
2571 if (unlikely(err < 0)) {
2572 kfree_skb(skb);
2573 return ERR_PTR(err);
2574 }
2575
2576 return skb;
2577}
2578
2579static int l2cap_segment_le_sdu(struct l2cap_chan *chan,
2580 struct sk_buff_head *seg_queue,
2581 struct msghdr *msg, size_t len)
2582{
2583 struct sk_buff *skb;
2584 size_t pdu_len;
2585 u16 sdu_len;
2586
2587 BT_DBG("chan %p, msg %p, len %zu", chan, msg, len);
2588
2589 sdu_len = len;
2590 pdu_len = chan->remote_mps - L2CAP_SDULEN_SIZE;
2591
2592 while (len > 0) {
2593 if (len <= pdu_len)
2594 pdu_len = len;
2595
2596 skb = l2cap_create_le_flowctl_pdu(chan, msg, pdu_len, sdu_len);
2597 if (IS_ERR(skb)) {
2598 __skb_queue_purge(seg_queue);
2599 return PTR_ERR(skb);
2600 }
2601
2602 __skb_queue_tail(seg_queue, skb);
2603
2604 len -= pdu_len;
2605
2606 if (sdu_len) {
2607 sdu_len = 0;
2608 pdu_len += L2CAP_SDULEN_SIZE;
2609 }
2610 }
2611
2612 return 0;
2613}
2614
2615static void l2cap_le_flowctl_send(struct l2cap_chan *chan)
2616{
2617 int sent = 0;
2618
2619 BT_DBG("chan %p", chan);
2620
2621 while (chan->tx_credits && !skb_queue_empty(&chan->tx_q)) {
2622 l2cap_do_send(chan, skb_dequeue(&chan->tx_q));
2623 chan->tx_credits--;
2624 sent++;
2625 }
2626
2627 BT_DBG("Sent %d credits %u queued %u", sent, chan->tx_credits,
2628 skb_queue_len(&chan->tx_q));
2629}
2630
2631int l2cap_chan_send(struct l2cap_chan *chan, struct msghdr *msg, size_t len)
2632{
2633 struct sk_buff *skb;
2634 int err;
2635 struct sk_buff_head seg_queue;
2636
2637 if (!chan->conn)
2638 return -ENOTCONN;
2639
2640 /* Connectionless channel */
2641 if (chan->chan_type == L2CAP_CHAN_CONN_LESS) {
2642 skb = l2cap_create_connless_pdu(chan, msg, len);
2643 if (IS_ERR(skb))
2644 return PTR_ERR(skb);
2645
2646 /* Channel lock is released before requesting new skb and then
2647 * reacquired thus we need to recheck channel state.
2648 */
2649 if (chan->state != BT_CONNECTED) {
2650 kfree_skb(skb);
2651 return -ENOTCONN;
2652 }
2653
2654 l2cap_do_send(chan, skb);
2655 return len;
2656 }
2657
2658 switch (chan->mode) {
2659 case L2CAP_MODE_LE_FLOWCTL:
2660 case L2CAP_MODE_EXT_FLOWCTL:
2661 /* Check outgoing MTU */
2662 if (len > chan->omtu)
2663 return -EMSGSIZE;
2664
2665 __skb_queue_head_init(&seg_queue);
2666
2667 err = l2cap_segment_le_sdu(chan, &seg_queue, msg, len);
2668
2669 if (chan->state != BT_CONNECTED) {
2670 __skb_queue_purge(&seg_queue);
2671 err = -ENOTCONN;
2672 }
2673
2674 if (err)
2675 return err;
2676
2677 skb_queue_splice_tail_init(&seg_queue, &chan->tx_q);
2678
2679 l2cap_le_flowctl_send(chan);
2680
2681 if (!chan->tx_credits)
2682 chan->ops->suspend(chan);
2683
2684 err = len;
2685
2686 break;
2687
2688 case L2CAP_MODE_BASIC:
2689 /* Check outgoing MTU */
2690 if (len > chan->omtu)
2691 return -EMSGSIZE;
2692
2693 /* Create a basic PDU */
2694 skb = l2cap_create_basic_pdu(chan, msg, len);
2695 if (IS_ERR(skb))
2696 return PTR_ERR(skb);
2697
2698 /* Channel lock is released before requesting new skb and then
2699 * reacquired thus we need to recheck channel state.
2700 */
2701 if (chan->state != BT_CONNECTED) {
2702 kfree_skb(skb);
2703 return -ENOTCONN;
2704 }
2705
2706 l2cap_do_send(chan, skb);
2707 err = len;
2708 break;
2709
2710 case L2CAP_MODE_ERTM:
2711 case L2CAP_MODE_STREAMING:
2712 /* Check outgoing MTU */
2713 if (len > chan->omtu) {
2714 err = -EMSGSIZE;
2715 break;
2716 }
2717
2718 __skb_queue_head_init(&seg_queue);
2719
2720 /* Do segmentation before calling in to the state machine,
2721 * since it's possible to block while waiting for memory
2722 * allocation.
2723 */
2724 err = l2cap_segment_sdu(chan, &seg_queue, msg, len);
2725
2726 /* The channel could have been closed while segmenting,
2727 * check that it is still connected.
2728 */
2729 if (chan->state != BT_CONNECTED) {
2730 __skb_queue_purge(&seg_queue);
2731 err = -ENOTCONN;
2732 }
2733
2734 if (err)
2735 break;
2736
2737 if (chan->mode == L2CAP_MODE_ERTM)
2738 l2cap_tx(chan, NULL, &seg_queue, L2CAP_EV_DATA_REQUEST);
2739 else
2740 l2cap_streaming_send(chan, &seg_queue);
2741
2742 err = len;
2743
2744 /* If the skbs were not queued for sending, they'll still be in
2745 * seg_queue and need to be purged.
2746 */
2747 __skb_queue_purge(&seg_queue);
2748 break;
2749
2750 default:
2751 BT_DBG("bad state %1.1x", chan->mode);
2752 err = -EBADFD;
2753 }
2754
2755 return err;
2756}
2757EXPORT_SYMBOL_GPL(l2cap_chan_send);
2758
2759static void l2cap_send_srej(struct l2cap_chan *chan, u16 txseq)
2760{
2761 struct l2cap_ctrl control;
2762 u16 seq;
2763
2764 BT_DBG("chan %p, txseq %u", chan, txseq);
2765
2766 memset(&control, 0, sizeof(control));
2767 control.sframe = 1;
2768 control.super = L2CAP_SUPER_SREJ;
2769
2770 for (seq = chan->expected_tx_seq; seq != txseq;
2771 seq = __next_seq(chan, seq)) {
2772 if (!l2cap_ertm_seq_in_queue(&chan->srej_q, seq)) {
2773 control.reqseq = seq;
2774 l2cap_send_sframe(chan, &control);
2775 l2cap_seq_list_append(&chan->srej_list, seq);
2776 }
2777 }
2778
2779 chan->expected_tx_seq = __next_seq(chan, txseq);
2780}
2781
2782static void l2cap_send_srej_tail(struct l2cap_chan *chan)
2783{
2784 struct l2cap_ctrl control;
2785
2786 BT_DBG("chan %p", chan);
2787
2788 if (chan->srej_list.tail == L2CAP_SEQ_LIST_CLEAR)
2789 return;
2790
2791 memset(&control, 0, sizeof(control));
2792 control.sframe = 1;
2793 control.super = L2CAP_SUPER_SREJ;
2794 control.reqseq = chan->srej_list.tail;
2795 l2cap_send_sframe(chan, &control);
2796}
2797
2798static void l2cap_send_srej_list(struct l2cap_chan *chan, u16 txseq)
2799{
2800 struct l2cap_ctrl control;
2801 u16 initial_head;
2802 u16 seq;
2803
2804 BT_DBG("chan %p, txseq %u", chan, txseq);
2805
2806 memset(&control, 0, sizeof(control));
2807 control.sframe = 1;
2808 control.super = L2CAP_SUPER_SREJ;
2809
2810 /* Capture initial list head to allow only one pass through the list. */
2811 initial_head = chan->srej_list.head;
2812
2813 do {
2814 seq = l2cap_seq_list_pop(&chan->srej_list);
2815 if (seq == txseq || seq == L2CAP_SEQ_LIST_CLEAR)
2816 break;
2817
2818 control.reqseq = seq;
2819 l2cap_send_sframe(chan, &control);
2820 l2cap_seq_list_append(&chan->srej_list, seq);
2821 } while (chan->srej_list.head != initial_head);
2822}
2823
2824static void l2cap_process_reqseq(struct l2cap_chan *chan, u16 reqseq)
2825{
2826 struct sk_buff *acked_skb;
2827 u16 ackseq;
2828
2829 BT_DBG("chan %p, reqseq %u", chan, reqseq);
2830
2831 if (chan->unacked_frames == 0 || reqseq == chan->expected_ack_seq)
2832 return;
2833
2834 BT_DBG("expected_ack_seq %u, unacked_frames %u",
2835 chan->expected_ack_seq, chan->unacked_frames);
2836
2837 for (ackseq = chan->expected_ack_seq; ackseq != reqseq;
2838 ackseq = __next_seq(chan, ackseq)) {
2839
2840 acked_skb = l2cap_ertm_seq_in_queue(&chan->tx_q, ackseq);
2841 if (acked_skb) {
2842 skb_unlink(acked_skb, &chan->tx_q);
2843 kfree_skb(acked_skb);
2844 chan->unacked_frames--;
2845 }
2846 }
2847
2848 chan->expected_ack_seq = reqseq;
2849
2850 if (chan->unacked_frames == 0)
2851 __clear_retrans_timer(chan);
2852
2853 BT_DBG("unacked_frames %u", chan->unacked_frames);
2854}
2855
2856static void l2cap_abort_rx_srej_sent(struct l2cap_chan *chan)
2857{
2858 BT_DBG("chan %p", chan);
2859
2860 chan->expected_tx_seq = chan->buffer_seq;
2861 l2cap_seq_list_clear(&chan->srej_list);
2862 skb_queue_purge(&chan->srej_q);
2863 chan->rx_state = L2CAP_RX_STATE_RECV;
2864}
2865
2866static void l2cap_tx_state_xmit(struct l2cap_chan *chan,
2867 struct l2cap_ctrl *control,
2868 struct sk_buff_head *skbs, u8 event)
2869{
2870 BT_DBG("chan %p, control %p, skbs %p, event %d", chan, control, skbs,
2871 event);
2872
2873 switch (event) {
2874 case L2CAP_EV_DATA_REQUEST:
2875 if (chan->tx_send_head == NULL)
2876 chan->tx_send_head = skb_peek(skbs);
2877
2878 skb_queue_splice_tail_init(skbs, &chan->tx_q);
2879 l2cap_ertm_send(chan);
2880 break;
2881 case L2CAP_EV_LOCAL_BUSY_DETECTED:
2882 BT_DBG("Enter LOCAL_BUSY");
2883 set_bit(CONN_LOCAL_BUSY, &chan->conn_state);
2884
2885 if (chan->rx_state == L2CAP_RX_STATE_SREJ_SENT) {
2886 /* The SREJ_SENT state must be aborted if we are to
2887 * enter the LOCAL_BUSY state.
2888 */
2889 l2cap_abort_rx_srej_sent(chan);
2890 }
2891
2892 l2cap_send_ack(chan);
2893
2894 break;
2895 case L2CAP_EV_LOCAL_BUSY_CLEAR:
2896 BT_DBG("Exit LOCAL_BUSY");
2897 clear_bit(CONN_LOCAL_BUSY, &chan->conn_state);
2898
2899 if (test_bit(CONN_RNR_SENT, &chan->conn_state)) {
2900 struct l2cap_ctrl local_control;
2901
2902 memset(&local_control, 0, sizeof(local_control));
2903 local_control.sframe = 1;
2904 local_control.super = L2CAP_SUPER_RR;
2905 local_control.poll = 1;
2906 local_control.reqseq = chan->buffer_seq;
2907 l2cap_send_sframe(chan, &local_control);
2908
2909 chan->retry_count = 1;
2910 __set_monitor_timer(chan);
2911 chan->tx_state = L2CAP_TX_STATE_WAIT_F;
2912 }
2913 break;
2914 case L2CAP_EV_RECV_REQSEQ_AND_FBIT:
2915 l2cap_process_reqseq(chan, control->reqseq);
2916 break;
2917 case L2CAP_EV_EXPLICIT_POLL:
2918 l2cap_send_rr_or_rnr(chan, 1);
2919 chan->retry_count = 1;
2920 __set_monitor_timer(chan);
2921 __clear_ack_timer(chan);
2922 chan->tx_state = L2CAP_TX_STATE_WAIT_F;
2923 break;
2924 case L2CAP_EV_RETRANS_TO:
2925 l2cap_send_rr_or_rnr(chan, 1);
2926 chan->retry_count = 1;
2927 __set_monitor_timer(chan);
2928 chan->tx_state = L2CAP_TX_STATE_WAIT_F;
2929 break;
2930 case L2CAP_EV_RECV_FBIT:
2931 /* Nothing to process */
2932 break;
2933 default:
2934 break;
2935 }
2936}
2937
2938static void l2cap_tx_state_wait_f(struct l2cap_chan *chan,
2939 struct l2cap_ctrl *control,
2940 struct sk_buff_head *skbs, u8 event)
2941{
2942 BT_DBG("chan %p, control %p, skbs %p, event %d", chan, control, skbs,
2943 event);
2944
2945 switch (event) {
2946 case L2CAP_EV_DATA_REQUEST:
2947 if (chan->tx_send_head == NULL)
2948 chan->tx_send_head = skb_peek(skbs);
2949 /* Queue data, but don't send. */
2950 skb_queue_splice_tail_init(skbs, &chan->tx_q);
2951 break;
2952 case L2CAP_EV_LOCAL_BUSY_DETECTED:
2953 BT_DBG("Enter LOCAL_BUSY");
2954 set_bit(CONN_LOCAL_BUSY, &chan->conn_state);
2955
2956 if (chan->rx_state == L2CAP_RX_STATE_SREJ_SENT) {
2957 /* The SREJ_SENT state must be aborted if we are to
2958 * enter the LOCAL_BUSY state.
2959 */
2960 l2cap_abort_rx_srej_sent(chan);
2961 }
2962
2963 l2cap_send_ack(chan);
2964
2965 break;
2966 case L2CAP_EV_LOCAL_BUSY_CLEAR:
2967 BT_DBG("Exit LOCAL_BUSY");
2968 clear_bit(CONN_LOCAL_BUSY, &chan->conn_state);
2969
2970 if (test_bit(CONN_RNR_SENT, &chan->conn_state)) {
2971 struct l2cap_ctrl local_control;
2972 memset(&local_control, 0, sizeof(local_control));
2973 local_control.sframe = 1;
2974 local_control.super = L2CAP_SUPER_RR;
2975 local_control.poll = 1;
2976 local_control.reqseq = chan->buffer_seq;
2977 l2cap_send_sframe(chan, &local_control);
2978
2979 chan->retry_count = 1;
2980 __set_monitor_timer(chan);
2981 chan->tx_state = L2CAP_TX_STATE_WAIT_F;
2982 }
2983 break;
2984 case L2CAP_EV_RECV_REQSEQ_AND_FBIT:
2985 l2cap_process_reqseq(chan, control->reqseq);
2986 fallthrough;
2987
2988 case L2CAP_EV_RECV_FBIT:
2989 if (control && control->final) {
2990 __clear_monitor_timer(chan);
2991 if (chan->unacked_frames > 0)
2992 __set_retrans_timer(chan);
2993 chan->retry_count = 0;
2994 chan->tx_state = L2CAP_TX_STATE_XMIT;
2995 BT_DBG("recv fbit tx_state 0x2.2%x", chan->tx_state);
2996 }
2997 break;
2998 case L2CAP_EV_EXPLICIT_POLL:
2999 /* Ignore */
3000 break;
3001 case L2CAP_EV_MONITOR_TO:
3002 if (chan->max_tx == 0 || chan->retry_count < chan->max_tx) {
3003 l2cap_send_rr_or_rnr(chan, 1);
3004 __set_monitor_timer(chan);
3005 chan->retry_count++;
3006 } else {
3007 l2cap_send_disconn_req(chan, ECONNABORTED);
3008 }
3009 break;
3010 default:
3011 break;
3012 }
3013}
3014
3015static void l2cap_tx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
3016 struct sk_buff_head *skbs, u8 event)
3017{
3018 BT_DBG("chan %p, control %p, skbs %p, event %d, state %d",
3019 chan, control, skbs, event, chan->tx_state);
3020
3021 switch (chan->tx_state) {
3022 case L2CAP_TX_STATE_XMIT:
3023 l2cap_tx_state_xmit(chan, control, skbs, event);
3024 break;
3025 case L2CAP_TX_STATE_WAIT_F:
3026 l2cap_tx_state_wait_f(chan, control, skbs, event);
3027 break;
3028 default:
3029 /* Ignore event */
3030 break;
3031 }
3032}
3033
3034static void l2cap_pass_to_tx(struct l2cap_chan *chan,
3035 struct l2cap_ctrl *control)
3036{
3037 BT_DBG("chan %p, control %p", chan, control);
3038 l2cap_tx(chan, control, NULL, L2CAP_EV_RECV_REQSEQ_AND_FBIT);
3039}
3040
3041static void l2cap_pass_to_tx_fbit(struct l2cap_chan *chan,
3042 struct l2cap_ctrl *control)
3043{
3044 BT_DBG("chan %p, control %p", chan, control);
3045 l2cap_tx(chan, control, NULL, L2CAP_EV_RECV_FBIT);
3046}
3047
3048/* Copy frame to all raw sockets on that connection */
3049static void l2cap_raw_recv(struct l2cap_conn *conn, struct sk_buff *skb)
3050{
3051 struct sk_buff *nskb;
3052 struct l2cap_chan *chan;
3053
3054 BT_DBG("conn %p", conn);
3055
3056 mutex_lock(&conn->chan_lock);
3057
3058 list_for_each_entry(chan, &conn->chan_l, list) {
3059 if (chan->chan_type != L2CAP_CHAN_RAW)
3060 continue;
3061
3062 /* Don't send frame to the channel it came from */
3063 if (bt_cb(skb)->l2cap.chan == chan)
3064 continue;
3065
3066 nskb = skb_clone(skb, GFP_KERNEL);
3067 if (!nskb)
3068 continue;
3069 if (chan->ops->recv(chan, nskb))
3070 kfree_skb(nskb);
3071 }
3072
3073 mutex_unlock(&conn->chan_lock);
3074}
3075
3076/* ---- L2CAP signalling commands ---- */
3077static struct sk_buff *l2cap_build_cmd(struct l2cap_conn *conn, u8 code,
3078 u8 ident, u16 dlen, void *data)
3079{
3080 struct sk_buff *skb, **frag;
3081 struct l2cap_cmd_hdr *cmd;
3082 struct l2cap_hdr *lh;
3083 int len, count;
3084
3085 BT_DBG("conn %p, code 0x%2.2x, ident 0x%2.2x, len %u",
3086 conn, code, ident, dlen);
3087
3088 if (conn->mtu < L2CAP_HDR_SIZE + L2CAP_CMD_HDR_SIZE)
3089 return NULL;
3090
3091 len = L2CAP_HDR_SIZE + L2CAP_CMD_HDR_SIZE + dlen;
3092 count = min_t(unsigned int, conn->mtu, len);
3093
3094 skb = bt_skb_alloc(count, GFP_KERNEL);
3095 if (!skb)
3096 return NULL;
3097
3098 lh = skb_put(skb, L2CAP_HDR_SIZE);
3099 lh->len = cpu_to_le16(L2CAP_CMD_HDR_SIZE + dlen);
3100
3101 if (conn->hcon->type == LE_LINK)
3102 lh->cid = cpu_to_le16(L2CAP_CID_LE_SIGNALING);
3103 else
3104 lh->cid = cpu_to_le16(L2CAP_CID_SIGNALING);
3105
3106 cmd = skb_put(skb, L2CAP_CMD_HDR_SIZE);
3107 cmd->code = code;
3108 cmd->ident = ident;
3109 cmd->len = cpu_to_le16(dlen);
3110
3111 if (dlen) {
3112 count -= L2CAP_HDR_SIZE + L2CAP_CMD_HDR_SIZE;
3113 skb_put_data(skb, data, count);
3114 data += count;
3115 }
3116
3117 len -= skb->len;
3118
3119 /* Continuation fragments (no L2CAP header) */
3120 frag = &skb_shinfo(skb)->frag_list;
3121 while (len) {
3122 count = min_t(unsigned int, conn->mtu, len);
3123
3124 *frag = bt_skb_alloc(count, GFP_KERNEL);
3125 if (!*frag)
3126 goto fail;
3127
3128 skb_put_data(*frag, data, count);
3129
3130 len -= count;
3131 data += count;
3132
3133 frag = &(*frag)->next;
3134 }
3135
3136 return skb;
3137
3138fail:
3139 kfree_skb(skb);
3140 return NULL;
3141}
3142
3143static inline int l2cap_get_conf_opt(void **ptr, int *type, int *olen,
3144 unsigned long *val)
3145{
3146 struct l2cap_conf_opt *opt = *ptr;
3147 int len;
3148
3149 len = L2CAP_CONF_OPT_SIZE + opt->len;
3150 *ptr += len;
3151
3152 *type = opt->type;
3153 *olen = opt->len;
3154
3155 switch (opt->len) {
3156 case 1:
3157 *val = *((u8 *) opt->val);
3158 break;
3159
3160 case 2:
3161 *val = get_unaligned_le16(opt->val);
3162 break;
3163
3164 case 4:
3165 *val = get_unaligned_le32(opt->val);
3166 break;
3167
3168 default:
3169 *val = (unsigned long) opt->val;
3170 break;
3171 }
3172
3173 BT_DBG("type 0x%2.2x len %u val 0x%lx", *type, opt->len, *val);
3174 return len;
3175}
3176
3177static void l2cap_add_conf_opt(void **ptr, u8 type, u8 len, unsigned long val, size_t size)
3178{
3179 struct l2cap_conf_opt *opt = *ptr;
3180
3181 BT_DBG("type 0x%2.2x len %u val 0x%lx", type, len, val);
3182
3183 if (size < L2CAP_CONF_OPT_SIZE + len)
3184 return;
3185
3186 opt->type = type;
3187 opt->len = len;
3188
3189 switch (len) {
3190 case 1:
3191 *((u8 *) opt->val) = val;
3192 break;
3193
3194 case 2:
3195 put_unaligned_le16(val, opt->val);
3196 break;
3197
3198 case 4:
3199 put_unaligned_le32(val, opt->val);
3200 break;
3201
3202 default:
3203 memcpy(opt->val, (void *) val, len);
3204 break;
3205 }
3206
3207 *ptr += L2CAP_CONF_OPT_SIZE + len;
3208}
3209
3210static void l2cap_add_opt_efs(void **ptr, struct l2cap_chan *chan, size_t size)
3211{
3212 struct l2cap_conf_efs efs;
3213
3214 switch (chan->mode) {
3215 case L2CAP_MODE_ERTM:
3216 efs.id = chan->local_id;
3217 efs.stype = chan->local_stype;
3218 efs.msdu = cpu_to_le16(chan->local_msdu);
3219 efs.sdu_itime = cpu_to_le32(chan->local_sdu_itime);
3220 efs.acc_lat = cpu_to_le32(L2CAP_DEFAULT_ACC_LAT);
3221 efs.flush_to = cpu_to_le32(L2CAP_EFS_DEFAULT_FLUSH_TO);
3222 break;
3223
3224 case L2CAP_MODE_STREAMING:
3225 efs.id = 1;
3226 efs.stype = L2CAP_SERV_BESTEFFORT;
3227 efs.msdu = cpu_to_le16(chan->local_msdu);
3228 efs.sdu_itime = cpu_to_le32(chan->local_sdu_itime);
3229 efs.acc_lat = 0;
3230 efs.flush_to = 0;
3231 break;
3232
3233 default:
3234 return;
3235 }
3236
3237 l2cap_add_conf_opt(ptr, L2CAP_CONF_EFS, sizeof(efs),
3238 (unsigned long) &efs, size);
3239}
3240
3241static void l2cap_ack_timeout(struct work_struct *work)
3242{
3243 struct l2cap_chan *chan = container_of(work, struct l2cap_chan,
3244 ack_timer.work);
3245 u16 frames_to_ack;
3246
3247 BT_DBG("chan %p", chan);
3248
3249 l2cap_chan_lock(chan);
3250
3251 frames_to_ack = __seq_offset(chan, chan->buffer_seq,
3252 chan->last_acked_seq);
3253
3254 if (frames_to_ack)
3255 l2cap_send_rr_or_rnr(chan, 0);
3256
3257 l2cap_chan_unlock(chan);
3258 l2cap_chan_put(chan);
3259}
3260
3261int l2cap_ertm_init(struct l2cap_chan *chan)
3262{
3263 int err;
3264
3265 chan->next_tx_seq = 0;
3266 chan->expected_tx_seq = 0;
3267 chan->expected_ack_seq = 0;
3268 chan->unacked_frames = 0;
3269 chan->buffer_seq = 0;
3270 chan->frames_sent = 0;
3271 chan->last_acked_seq = 0;
3272 chan->sdu = NULL;
3273 chan->sdu_last_frag = NULL;
3274 chan->sdu_len = 0;
3275
3276 skb_queue_head_init(&chan->tx_q);
3277
3278 chan->local_amp_id = AMP_ID_BREDR;
3279 chan->move_id = AMP_ID_BREDR;
3280 chan->move_state = L2CAP_MOVE_STABLE;
3281 chan->move_role = L2CAP_MOVE_ROLE_NONE;
3282
3283 if (chan->mode != L2CAP_MODE_ERTM)
3284 return 0;
3285
3286 chan->rx_state = L2CAP_RX_STATE_RECV;
3287 chan->tx_state = L2CAP_TX_STATE_XMIT;
3288
3289 INIT_DELAYED_WORK(&chan->retrans_timer, l2cap_retrans_timeout);
3290 INIT_DELAYED_WORK(&chan->monitor_timer, l2cap_monitor_timeout);
3291 INIT_DELAYED_WORK(&chan->ack_timer, l2cap_ack_timeout);
3292
3293 skb_queue_head_init(&chan->srej_q);
3294
3295 err = l2cap_seq_list_init(&chan->srej_list, chan->tx_win);
3296 if (err < 0)
3297 return err;
3298
3299 err = l2cap_seq_list_init(&chan->retrans_list, chan->remote_tx_win);
3300 if (err < 0)
3301 l2cap_seq_list_free(&chan->srej_list);
3302
3303 return err;
3304}
3305
3306static inline __u8 l2cap_select_mode(__u8 mode, __u16 remote_feat_mask)
3307{
3308 switch (mode) {
3309 case L2CAP_MODE_STREAMING:
3310 case L2CAP_MODE_ERTM:
3311 if (l2cap_mode_supported(mode, remote_feat_mask))
3312 return mode;
3313 fallthrough;
3314 default:
3315 return L2CAP_MODE_BASIC;
3316 }
3317}
3318
3319static inline bool __l2cap_ews_supported(struct l2cap_conn *conn)
3320{
3321 return ((conn->local_fixed_chan & L2CAP_FC_A2MP) &&
3322 (conn->feat_mask & L2CAP_FEAT_EXT_WINDOW));
3323}
3324
3325static inline bool __l2cap_efs_supported(struct l2cap_conn *conn)
3326{
3327 return ((conn->local_fixed_chan & L2CAP_FC_A2MP) &&
3328 (conn->feat_mask & L2CAP_FEAT_EXT_FLOW));
3329}
3330
3331static void __l2cap_set_ertm_timeouts(struct l2cap_chan *chan,
3332 struct l2cap_conf_rfc *rfc)
3333{
3334 if (chan->local_amp_id != AMP_ID_BREDR && chan->hs_hcon) {
3335 u64 ertm_to = chan->hs_hcon->hdev->amp_be_flush_to;
3336
3337 /* Class 1 devices have must have ERTM timeouts
3338 * exceeding the Link Supervision Timeout. The
3339 * default Link Supervision Timeout for AMP
3340 * controllers is 10 seconds.
3341 *
3342 * Class 1 devices use 0xffffffff for their
3343 * best-effort flush timeout, so the clamping logic
3344 * will result in a timeout that meets the above
3345 * requirement. ERTM timeouts are 16-bit values, so
3346 * the maximum timeout is 65.535 seconds.
3347 */
3348
3349 /* Convert timeout to milliseconds and round */
3350 ertm_to = DIV_ROUND_UP_ULL(ertm_to, 1000);
3351
3352 /* This is the recommended formula for class 2 devices
3353 * that start ERTM timers when packets are sent to the
3354 * controller.
3355 */
3356 ertm_to = 3 * ertm_to + 500;
3357
3358 if (ertm_to > 0xffff)
3359 ertm_to = 0xffff;
3360
3361 rfc->retrans_timeout = cpu_to_le16((u16) ertm_to);
3362 rfc->monitor_timeout = rfc->retrans_timeout;
3363 } else {
3364 rfc->retrans_timeout = cpu_to_le16(L2CAP_DEFAULT_RETRANS_TO);
3365 rfc->monitor_timeout = cpu_to_le16(L2CAP_DEFAULT_MONITOR_TO);
3366 }
3367}
3368
3369static inline void l2cap_txwin_setup(struct l2cap_chan *chan)
3370{
3371 if (chan->tx_win > L2CAP_DEFAULT_TX_WINDOW &&
3372 __l2cap_ews_supported(chan->conn)) {
3373 /* use extended control field */
3374 set_bit(FLAG_EXT_CTRL, &chan->flags);
3375 chan->tx_win_max = L2CAP_DEFAULT_EXT_WINDOW;
3376 } else {
3377 chan->tx_win = min_t(u16, chan->tx_win,
3378 L2CAP_DEFAULT_TX_WINDOW);
3379 chan->tx_win_max = L2CAP_DEFAULT_TX_WINDOW;
3380 }
3381 chan->ack_win = chan->tx_win;
3382}
3383
3384static void l2cap_mtu_auto(struct l2cap_chan *chan)
3385{
3386 struct hci_conn *conn = chan->conn->hcon;
3387
3388 chan->imtu = L2CAP_DEFAULT_MIN_MTU;
3389
3390 /* The 2-DH1 packet has between 2 and 56 information bytes
3391 * (including the 2-byte payload header)
3392 */
3393 if (!(conn->pkt_type & HCI_2DH1))
3394 chan->imtu = 54;
3395
3396 /* The 3-DH1 packet has between 2 and 85 information bytes
3397 * (including the 2-byte payload header)
3398 */
3399 if (!(conn->pkt_type & HCI_3DH1))
3400 chan->imtu = 83;
3401
3402 /* The 2-DH3 packet has between 2 and 369 information bytes
3403 * (including the 2-byte payload header)
3404 */
3405 if (!(conn->pkt_type & HCI_2DH3))
3406 chan->imtu = 367;
3407
3408 /* The 3-DH3 packet has between 2 and 554 information bytes
3409 * (including the 2-byte payload header)
3410 */
3411 if (!(conn->pkt_type & HCI_3DH3))
3412 chan->imtu = 552;
3413
3414 /* The 2-DH5 packet has between 2 and 681 information bytes
3415 * (including the 2-byte payload header)
3416 */
3417 if (!(conn->pkt_type & HCI_2DH5))
3418 chan->imtu = 679;
3419
3420 /* The 3-DH5 packet has between 2 and 1023 information bytes
3421 * (including the 2-byte payload header)
3422 */
3423 if (!(conn->pkt_type & HCI_3DH5))
3424 chan->imtu = 1021;
3425}
3426
3427static int l2cap_build_conf_req(struct l2cap_chan *chan, void *data, size_t data_size)
3428{
3429 struct l2cap_conf_req *req = data;
3430 struct l2cap_conf_rfc rfc = { .mode = chan->mode };
3431 void *ptr = req->data;
3432 void *endptr = data + data_size;
3433 u16 size;
3434
3435 BT_DBG("chan %p", chan);
3436
3437 if (chan->num_conf_req || chan->num_conf_rsp)
3438 goto done;
3439
3440 switch (chan->mode) {
3441 case L2CAP_MODE_STREAMING:
3442 case L2CAP_MODE_ERTM:
3443 if (test_bit(CONF_STATE2_DEVICE, &chan->conf_state))
3444 break;
3445
3446 if (__l2cap_efs_supported(chan->conn))
3447 set_bit(FLAG_EFS_ENABLE, &chan->flags);
3448
3449 fallthrough;
3450 default:
3451 chan->mode = l2cap_select_mode(rfc.mode, chan->conn->feat_mask);
3452 break;
3453 }
3454
3455done:
3456 if (chan->imtu != L2CAP_DEFAULT_MTU) {
3457 if (!chan->imtu)
3458 l2cap_mtu_auto(chan);
3459 l2cap_add_conf_opt(&ptr, L2CAP_CONF_MTU, 2, chan->imtu,
3460 endptr - ptr);
3461 }
3462
3463 switch (chan->mode) {
3464 case L2CAP_MODE_BASIC:
3465 if (disable_ertm)
3466 break;
3467
3468 if (!(chan->conn->feat_mask & L2CAP_FEAT_ERTM) &&
3469 !(chan->conn->feat_mask & L2CAP_FEAT_STREAMING))
3470 break;
3471
3472 rfc.mode = L2CAP_MODE_BASIC;
3473 rfc.txwin_size = 0;
3474 rfc.max_transmit = 0;
3475 rfc.retrans_timeout = 0;
3476 rfc.monitor_timeout = 0;
3477 rfc.max_pdu_size = 0;
3478
3479 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3480 (unsigned long) &rfc, endptr - ptr);
3481 break;
3482
3483 case L2CAP_MODE_ERTM:
3484 rfc.mode = L2CAP_MODE_ERTM;
3485 rfc.max_transmit = chan->max_tx;
3486
3487 __l2cap_set_ertm_timeouts(chan, &rfc);
3488
3489 size = min_t(u16, L2CAP_DEFAULT_MAX_PDU_SIZE, chan->conn->mtu -
3490 L2CAP_EXT_HDR_SIZE - L2CAP_SDULEN_SIZE -
3491 L2CAP_FCS_SIZE);
3492 rfc.max_pdu_size = cpu_to_le16(size);
3493
3494 l2cap_txwin_setup(chan);
3495
3496 rfc.txwin_size = min_t(u16, chan->tx_win,
3497 L2CAP_DEFAULT_TX_WINDOW);
3498
3499 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3500 (unsigned long) &rfc, endptr - ptr);
3501
3502 if (test_bit(FLAG_EFS_ENABLE, &chan->flags))
3503 l2cap_add_opt_efs(&ptr, chan, endptr - ptr);
3504
3505 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
3506 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EWS, 2,
3507 chan->tx_win, endptr - ptr);
3508
3509 if (chan->conn->feat_mask & L2CAP_FEAT_FCS)
3510 if (chan->fcs == L2CAP_FCS_NONE ||
3511 test_bit(CONF_RECV_NO_FCS, &chan->conf_state)) {
3512 chan->fcs = L2CAP_FCS_NONE;
3513 l2cap_add_conf_opt(&ptr, L2CAP_CONF_FCS, 1,
3514 chan->fcs, endptr - ptr);
3515 }
3516 break;
3517
3518 case L2CAP_MODE_STREAMING:
3519 l2cap_txwin_setup(chan);
3520 rfc.mode = L2CAP_MODE_STREAMING;
3521 rfc.txwin_size = 0;
3522 rfc.max_transmit = 0;
3523 rfc.retrans_timeout = 0;
3524 rfc.monitor_timeout = 0;
3525
3526 size = min_t(u16, L2CAP_DEFAULT_MAX_PDU_SIZE, chan->conn->mtu -
3527 L2CAP_EXT_HDR_SIZE - L2CAP_SDULEN_SIZE -
3528 L2CAP_FCS_SIZE);
3529 rfc.max_pdu_size = cpu_to_le16(size);
3530
3531 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3532 (unsigned long) &rfc, endptr - ptr);
3533
3534 if (test_bit(FLAG_EFS_ENABLE, &chan->flags))
3535 l2cap_add_opt_efs(&ptr, chan, endptr - ptr);
3536
3537 if (chan->conn->feat_mask & L2CAP_FEAT_FCS)
3538 if (chan->fcs == L2CAP_FCS_NONE ||
3539 test_bit(CONF_RECV_NO_FCS, &chan->conf_state)) {
3540 chan->fcs = L2CAP_FCS_NONE;
3541 l2cap_add_conf_opt(&ptr, L2CAP_CONF_FCS, 1,
3542 chan->fcs, endptr - ptr);
3543 }
3544 break;
3545 }
3546
3547 req->dcid = cpu_to_le16(chan->dcid);
3548 req->flags = cpu_to_le16(0);
3549
3550 return ptr - data;
3551}
3552
3553static int l2cap_parse_conf_req(struct l2cap_chan *chan, void *data, size_t data_size)
3554{
3555 struct l2cap_conf_rsp *rsp = data;
3556 void *ptr = rsp->data;
3557 void *endptr = data + data_size;
3558 void *req = chan->conf_req;
3559 int len = chan->conf_len;
3560 int type, hint, olen;
3561 unsigned long val;
3562 struct l2cap_conf_rfc rfc = { .mode = L2CAP_MODE_BASIC };
3563 struct l2cap_conf_efs efs;
3564 u8 remote_efs = 0;
3565 u16 mtu = L2CAP_DEFAULT_MTU;
3566 u16 result = L2CAP_CONF_SUCCESS;
3567 u16 size;
3568
3569 BT_DBG("chan %p", chan);
3570
3571 while (len >= L2CAP_CONF_OPT_SIZE) {
3572 len -= l2cap_get_conf_opt(&req, &type, &olen, &val);
3573 if (len < 0)
3574 break;
3575
3576 hint = type & L2CAP_CONF_HINT;
3577 type &= L2CAP_CONF_MASK;
3578
3579 switch (type) {
3580 case L2CAP_CONF_MTU:
3581 if (olen != 2)
3582 break;
3583 mtu = val;
3584 break;
3585
3586 case L2CAP_CONF_FLUSH_TO:
3587 if (olen != 2)
3588 break;
3589 chan->flush_to = val;
3590 break;
3591
3592 case L2CAP_CONF_QOS:
3593 break;
3594
3595 case L2CAP_CONF_RFC:
3596 if (olen != sizeof(rfc))
3597 break;
3598 memcpy(&rfc, (void *) val, olen);
3599 break;
3600
3601 case L2CAP_CONF_FCS:
3602 if (olen != 1)
3603 break;
3604 if (val == L2CAP_FCS_NONE)
3605 set_bit(CONF_RECV_NO_FCS, &chan->conf_state);
3606 break;
3607
3608 case L2CAP_CONF_EFS:
3609 if (olen != sizeof(efs))
3610 break;
3611 remote_efs = 1;
3612 memcpy(&efs, (void *) val, olen);
3613 break;
3614
3615 case L2CAP_CONF_EWS:
3616 if (olen != 2)
3617 break;
3618 if (!(chan->conn->local_fixed_chan & L2CAP_FC_A2MP))
3619 return -ECONNREFUSED;
3620 set_bit(FLAG_EXT_CTRL, &chan->flags);
3621 set_bit(CONF_EWS_RECV, &chan->conf_state);
3622 chan->tx_win_max = L2CAP_DEFAULT_EXT_WINDOW;
3623 chan->remote_tx_win = val;
3624 break;
3625
3626 default:
3627 if (hint)
3628 break;
3629 result = L2CAP_CONF_UNKNOWN;
3630 *((u8 *) ptr++) = type;
3631 break;
3632 }
3633 }
3634
3635 if (chan->num_conf_rsp || chan->num_conf_req > 1)
3636 goto done;
3637
3638 switch (chan->mode) {
3639 case L2CAP_MODE_STREAMING:
3640 case L2CAP_MODE_ERTM:
3641 if (!test_bit(CONF_STATE2_DEVICE, &chan->conf_state)) {
3642 chan->mode = l2cap_select_mode(rfc.mode,
3643 chan->conn->feat_mask);
3644 break;
3645 }
3646
3647 if (remote_efs) {
3648 if (__l2cap_efs_supported(chan->conn))
3649 set_bit(FLAG_EFS_ENABLE, &chan->flags);
3650 else
3651 return -ECONNREFUSED;
3652 }
3653
3654 if (chan->mode != rfc.mode)
3655 return -ECONNREFUSED;
3656
3657 break;
3658 }
3659
3660done:
3661 if (chan->mode != rfc.mode) {
3662 result = L2CAP_CONF_UNACCEPT;
3663 rfc.mode = chan->mode;
3664
3665 if (chan->num_conf_rsp == 1)
3666 return -ECONNREFUSED;
3667
3668 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3669 (unsigned long) &rfc, endptr - ptr);
3670 }
3671
3672 if (result == L2CAP_CONF_SUCCESS) {
3673 /* Configure output options and let the other side know
3674 * which ones we don't like. */
3675
3676 if (mtu < L2CAP_DEFAULT_MIN_MTU)
3677 result = L2CAP_CONF_UNACCEPT;
3678 else {
3679 chan->omtu = mtu;
3680 set_bit(CONF_MTU_DONE, &chan->conf_state);
3681 }
3682 l2cap_add_conf_opt(&ptr, L2CAP_CONF_MTU, 2, chan->omtu, endptr - ptr);
3683
3684 if (remote_efs) {
3685 if (chan->local_stype != L2CAP_SERV_NOTRAFIC &&
3686 efs.stype != L2CAP_SERV_NOTRAFIC &&
3687 efs.stype != chan->local_stype) {
3688
3689 result = L2CAP_CONF_UNACCEPT;
3690
3691 if (chan->num_conf_req >= 1)
3692 return -ECONNREFUSED;
3693
3694 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EFS,
3695 sizeof(efs),
3696 (unsigned long) &efs, endptr - ptr);
3697 } else {
3698 /* Send PENDING Conf Rsp */
3699 result = L2CAP_CONF_PENDING;
3700 set_bit(CONF_LOC_CONF_PEND, &chan->conf_state);
3701 }
3702 }
3703
3704 switch (rfc.mode) {
3705 case L2CAP_MODE_BASIC:
3706 chan->fcs = L2CAP_FCS_NONE;
3707 set_bit(CONF_MODE_DONE, &chan->conf_state);
3708 break;
3709
3710 case L2CAP_MODE_ERTM:
3711 if (!test_bit(CONF_EWS_RECV, &chan->conf_state))
3712 chan->remote_tx_win = rfc.txwin_size;
3713 else
3714 rfc.txwin_size = L2CAP_DEFAULT_TX_WINDOW;
3715
3716 chan->remote_max_tx = rfc.max_transmit;
3717
3718 size = min_t(u16, le16_to_cpu(rfc.max_pdu_size),
3719 chan->conn->mtu - L2CAP_EXT_HDR_SIZE -
3720 L2CAP_SDULEN_SIZE - L2CAP_FCS_SIZE);
3721 rfc.max_pdu_size = cpu_to_le16(size);
3722 chan->remote_mps = size;
3723
3724 __l2cap_set_ertm_timeouts(chan, &rfc);
3725
3726 set_bit(CONF_MODE_DONE, &chan->conf_state);
3727
3728 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC,
3729 sizeof(rfc), (unsigned long) &rfc, endptr - ptr);
3730
3731 if (test_bit(FLAG_EFS_ENABLE, &chan->flags)) {
3732 chan->remote_id = efs.id;
3733 chan->remote_stype = efs.stype;
3734 chan->remote_msdu = le16_to_cpu(efs.msdu);
3735 chan->remote_flush_to =
3736 le32_to_cpu(efs.flush_to);
3737 chan->remote_acc_lat =
3738 le32_to_cpu(efs.acc_lat);
3739 chan->remote_sdu_itime =
3740 le32_to_cpu(efs.sdu_itime);
3741 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EFS,
3742 sizeof(efs),
3743 (unsigned long) &efs, endptr - ptr);
3744 }
3745 break;
3746
3747 case L2CAP_MODE_STREAMING:
3748 size = min_t(u16, le16_to_cpu(rfc.max_pdu_size),
3749 chan->conn->mtu - L2CAP_EXT_HDR_SIZE -
3750 L2CAP_SDULEN_SIZE - L2CAP_FCS_SIZE);
3751 rfc.max_pdu_size = cpu_to_le16(size);
3752 chan->remote_mps = size;
3753
3754 set_bit(CONF_MODE_DONE, &chan->conf_state);
3755
3756 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3757 (unsigned long) &rfc, endptr - ptr);
3758
3759 break;
3760
3761 default:
3762 result = L2CAP_CONF_UNACCEPT;
3763
3764 memset(&rfc, 0, sizeof(rfc));
3765 rfc.mode = chan->mode;
3766 }
3767
3768 if (result == L2CAP_CONF_SUCCESS)
3769 set_bit(CONF_OUTPUT_DONE, &chan->conf_state);
3770 }
3771 rsp->scid = cpu_to_le16(chan->dcid);
3772 rsp->result = cpu_to_le16(result);
3773 rsp->flags = cpu_to_le16(0);
3774
3775 return ptr - data;
3776}
3777
3778static int l2cap_parse_conf_rsp(struct l2cap_chan *chan, void *rsp, int len,
3779 void *data, size_t size, u16 *result)
3780{
3781 struct l2cap_conf_req *req = data;
3782 void *ptr = req->data;
3783 void *endptr = data + size;
3784 int type, olen;
3785 unsigned long val;
3786 struct l2cap_conf_rfc rfc = { .mode = L2CAP_MODE_BASIC };
3787 struct l2cap_conf_efs efs;
3788
3789 BT_DBG("chan %p, rsp %p, len %d, req %p", chan, rsp, len, data);
3790
3791 while (len >= L2CAP_CONF_OPT_SIZE) {
3792 len -= l2cap_get_conf_opt(&rsp, &type, &olen, &val);
3793 if (len < 0)
3794 break;
3795
3796 switch (type) {
3797 case L2CAP_CONF_MTU:
3798 if (olen != 2)
3799 break;
3800 if (val < L2CAP_DEFAULT_MIN_MTU) {
3801 *result = L2CAP_CONF_UNACCEPT;
3802 chan->imtu = L2CAP_DEFAULT_MIN_MTU;
3803 } else
3804 chan->imtu = val;
3805 l2cap_add_conf_opt(&ptr, L2CAP_CONF_MTU, 2, chan->imtu,
3806 endptr - ptr);
3807 break;
3808
3809 case L2CAP_CONF_FLUSH_TO:
3810 if (olen != 2)
3811 break;
3812 chan->flush_to = val;
3813 l2cap_add_conf_opt(&ptr, L2CAP_CONF_FLUSH_TO, 2,
3814 chan->flush_to, endptr - ptr);
3815 break;
3816
3817 case L2CAP_CONF_RFC:
3818 if (olen != sizeof(rfc))
3819 break;
3820 memcpy(&rfc, (void *)val, olen);
3821 if (test_bit(CONF_STATE2_DEVICE, &chan->conf_state) &&
3822 rfc.mode != chan->mode)
3823 return -ECONNREFUSED;
3824 chan->fcs = 0;
3825 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3826 (unsigned long) &rfc, endptr - ptr);
3827 break;
3828
3829 case L2CAP_CONF_EWS:
3830 if (olen != 2)
3831 break;
3832 chan->ack_win = min_t(u16, val, chan->ack_win);
3833 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EWS, 2,
3834 chan->tx_win, endptr - ptr);
3835 break;
3836
3837 case L2CAP_CONF_EFS:
3838 if (olen != sizeof(efs))
3839 break;
3840 memcpy(&efs, (void *)val, olen);
3841 if (chan->local_stype != L2CAP_SERV_NOTRAFIC &&
3842 efs.stype != L2CAP_SERV_NOTRAFIC &&
3843 efs.stype != chan->local_stype)
3844 return -ECONNREFUSED;
3845 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EFS, sizeof(efs),
3846 (unsigned long) &efs, endptr - ptr);
3847 break;
3848
3849 case L2CAP_CONF_FCS:
3850 if (olen != 1)
3851 break;
3852 if (*result == L2CAP_CONF_PENDING)
3853 if (val == L2CAP_FCS_NONE)
3854 set_bit(CONF_RECV_NO_FCS,
3855 &chan->conf_state);
3856 break;
3857 }
3858 }
3859
3860 if (chan->mode == L2CAP_MODE_BASIC && chan->mode != rfc.mode)
3861 return -ECONNREFUSED;
3862
3863 chan->mode = rfc.mode;
3864
3865 if (*result == L2CAP_CONF_SUCCESS || *result == L2CAP_CONF_PENDING) {
3866 switch (rfc.mode) {
3867 case L2CAP_MODE_ERTM:
3868 chan->retrans_timeout = le16_to_cpu(rfc.retrans_timeout);
3869 chan->monitor_timeout = le16_to_cpu(rfc.monitor_timeout);
3870 chan->mps = le16_to_cpu(rfc.max_pdu_size);
3871 if (!test_bit(FLAG_EXT_CTRL, &chan->flags))
3872 chan->ack_win = min_t(u16, chan->ack_win,
3873 rfc.txwin_size);
3874
3875 if (test_bit(FLAG_EFS_ENABLE, &chan->flags)) {
3876 chan->local_msdu = le16_to_cpu(efs.msdu);
3877 chan->local_sdu_itime =
3878 le32_to_cpu(efs.sdu_itime);
3879 chan->local_acc_lat = le32_to_cpu(efs.acc_lat);
3880 chan->local_flush_to =
3881 le32_to_cpu(efs.flush_to);
3882 }
3883 break;
3884
3885 case L2CAP_MODE_STREAMING:
3886 chan->mps = le16_to_cpu(rfc.max_pdu_size);
3887 }
3888 }
3889
3890 req->dcid = cpu_to_le16(chan->dcid);
3891 req->flags = cpu_to_le16(0);
3892
3893 return ptr - data;
3894}
3895
3896static int l2cap_build_conf_rsp(struct l2cap_chan *chan, void *data,
3897 u16 result, u16 flags)
3898{
3899 struct l2cap_conf_rsp *rsp = data;
3900 void *ptr = rsp->data;
3901
3902 BT_DBG("chan %p", chan);
3903
3904 rsp->scid = cpu_to_le16(chan->dcid);
3905 rsp->result = cpu_to_le16(result);
3906 rsp->flags = cpu_to_le16(flags);
3907
3908 return ptr - data;
3909}
3910
3911void __l2cap_le_connect_rsp_defer(struct l2cap_chan *chan)
3912{
3913 struct l2cap_le_conn_rsp rsp;
3914 struct l2cap_conn *conn = chan->conn;
3915
3916 BT_DBG("chan %p", chan);
3917
3918 rsp.dcid = cpu_to_le16(chan->scid);
3919 rsp.mtu = cpu_to_le16(chan->imtu);
3920 rsp.mps = cpu_to_le16(chan->mps);
3921 rsp.credits = cpu_to_le16(chan->rx_credits);
3922 rsp.result = cpu_to_le16(L2CAP_CR_LE_SUCCESS);
3923
3924 l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CONN_RSP, sizeof(rsp),
3925 &rsp);
3926}
3927
3928void __l2cap_ecred_conn_rsp_defer(struct l2cap_chan *chan)
3929{
3930 struct {
3931 struct l2cap_ecred_conn_rsp rsp;
3932 __le16 dcid[5];
3933 } __packed pdu;
3934 struct l2cap_conn *conn = chan->conn;
3935 u16 ident = chan->ident;
3936 int i = 0;
3937
3938 if (!ident)
3939 return;
3940
3941 BT_DBG("chan %p ident %d", chan, ident);
3942
3943 pdu.rsp.mtu = cpu_to_le16(chan->imtu);
3944 pdu.rsp.mps = cpu_to_le16(chan->mps);
3945 pdu.rsp.credits = cpu_to_le16(chan->rx_credits);
3946 pdu.rsp.result = cpu_to_le16(L2CAP_CR_LE_SUCCESS);
3947
3948 mutex_lock(&conn->chan_lock);
3949
3950 list_for_each_entry(chan, &conn->chan_l, list) {
3951 if (chan->ident != ident)
3952 continue;
3953
3954 /* Reset ident so only one response is sent */
3955 chan->ident = 0;
3956
3957 /* Include all channels pending with the same ident */
3958 pdu.dcid[i++] = cpu_to_le16(chan->scid);
3959 }
3960
3961 mutex_unlock(&conn->chan_lock);
3962
3963 l2cap_send_cmd(conn, ident, L2CAP_ECRED_CONN_RSP,
3964 sizeof(pdu.rsp) + i * sizeof(__le16), &pdu);
3965}
3966
3967void __l2cap_connect_rsp_defer(struct l2cap_chan *chan)
3968{
3969 struct l2cap_conn_rsp rsp;
3970 struct l2cap_conn *conn = chan->conn;
3971 u8 buf[128];
3972 u8 rsp_code;
3973
3974 rsp.scid = cpu_to_le16(chan->dcid);
3975 rsp.dcid = cpu_to_le16(chan->scid);
3976 rsp.result = cpu_to_le16(L2CAP_CR_SUCCESS);
3977 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
3978
3979 if (chan->hs_hcon)
3980 rsp_code = L2CAP_CREATE_CHAN_RSP;
3981 else
3982 rsp_code = L2CAP_CONN_RSP;
3983
3984 BT_DBG("chan %p rsp_code %u", chan, rsp_code);
3985
3986 l2cap_send_cmd(conn, chan->ident, rsp_code, sizeof(rsp), &rsp);
3987
3988 if (test_and_set_bit(CONF_REQ_SENT, &chan->conf_state))
3989 return;
3990
3991 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
3992 l2cap_build_conf_req(chan, buf, sizeof(buf)), buf);
3993 chan->num_conf_req++;
3994}
3995
3996static void l2cap_conf_rfc_get(struct l2cap_chan *chan, void *rsp, int len)
3997{
3998 int type, olen;
3999 unsigned long val;
4000 /* Use sane default values in case a misbehaving remote device
4001 * did not send an RFC or extended window size option.
4002 */
4003 u16 txwin_ext = chan->ack_win;
4004 struct l2cap_conf_rfc rfc = {
4005 .mode = chan->mode,
4006 .retrans_timeout = cpu_to_le16(L2CAP_DEFAULT_RETRANS_TO),
4007 .monitor_timeout = cpu_to_le16(L2CAP_DEFAULT_MONITOR_TO),
4008 .max_pdu_size = cpu_to_le16(chan->imtu),
4009 .txwin_size = min_t(u16, chan->ack_win, L2CAP_DEFAULT_TX_WINDOW),
4010 };
4011
4012 BT_DBG("chan %p, rsp %p, len %d", chan, rsp, len);
4013
4014 if ((chan->mode != L2CAP_MODE_ERTM) && (chan->mode != L2CAP_MODE_STREAMING))
4015 return;
4016
4017 while (len >= L2CAP_CONF_OPT_SIZE) {
4018 len -= l2cap_get_conf_opt(&rsp, &type, &olen, &val);
4019 if (len < 0)
4020 break;
4021
4022 switch (type) {
4023 case L2CAP_CONF_RFC:
4024 if (olen != sizeof(rfc))
4025 break;
4026 memcpy(&rfc, (void *)val, olen);
4027 break;
4028 case L2CAP_CONF_EWS:
4029 if (olen != 2)
4030 break;
4031 txwin_ext = val;
4032 break;
4033 }
4034 }
4035
4036 switch (rfc.mode) {
4037 case L2CAP_MODE_ERTM:
4038 chan->retrans_timeout = le16_to_cpu(rfc.retrans_timeout);
4039 chan->monitor_timeout = le16_to_cpu(rfc.monitor_timeout);
4040 chan->mps = le16_to_cpu(rfc.max_pdu_size);
4041 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
4042 chan->ack_win = min_t(u16, chan->ack_win, txwin_ext);
4043 else
4044 chan->ack_win = min_t(u16, chan->ack_win,
4045 rfc.txwin_size);
4046 break;
4047 case L2CAP_MODE_STREAMING:
4048 chan->mps = le16_to_cpu(rfc.max_pdu_size);
4049 }
4050}
4051
4052static inline int l2cap_command_rej(struct l2cap_conn *conn,
4053 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4054 u8 *data)
4055{
4056 struct l2cap_cmd_rej_unk *rej = (struct l2cap_cmd_rej_unk *) data;
4057
4058 if (cmd_len < sizeof(*rej))
4059 return -EPROTO;
4060
4061 if (rej->reason != L2CAP_REJ_NOT_UNDERSTOOD)
4062 return 0;
4063
4064 if ((conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT) &&
4065 cmd->ident == conn->info_ident) {
4066 cancel_delayed_work(&conn->info_timer);
4067
4068 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
4069 conn->info_ident = 0;
4070
4071 l2cap_conn_start(conn);
4072 }
4073
4074 return 0;
4075}
4076
4077static struct l2cap_chan *l2cap_connect(struct l2cap_conn *conn,
4078 struct l2cap_cmd_hdr *cmd,
4079 u8 *data, u8 rsp_code, u8 amp_id)
4080{
4081 struct l2cap_conn_req *req = (struct l2cap_conn_req *) data;
4082 struct l2cap_conn_rsp rsp;
4083 struct l2cap_chan *chan = NULL, *pchan;
4084 int result, status = L2CAP_CS_NO_INFO;
4085
4086 u16 dcid = 0, scid = __le16_to_cpu(req->scid);
4087 __le16 psm = req->psm;
4088
4089 BT_DBG("psm 0x%2.2x scid 0x%4.4x", __le16_to_cpu(psm), scid);
4090
4091 /* Check if we have socket listening on psm */
4092 pchan = l2cap_global_chan_by_psm(BT_LISTEN, psm, &conn->hcon->src,
4093 &conn->hcon->dst, ACL_LINK);
4094 if (!pchan) {
4095 result = L2CAP_CR_BAD_PSM;
4096 goto sendresp;
4097 }
4098
4099 mutex_lock(&conn->chan_lock);
4100 l2cap_chan_lock(pchan);
4101
4102 /* Check if the ACL is secure enough (if not SDP) */
4103 if (psm != cpu_to_le16(L2CAP_PSM_SDP) &&
4104 !hci_conn_check_link_mode(conn->hcon)) {
4105 conn->disc_reason = HCI_ERROR_AUTH_FAILURE;
4106 result = L2CAP_CR_SEC_BLOCK;
4107 goto response;
4108 }
4109
4110 result = L2CAP_CR_NO_MEM;
4111
4112 /* Check for valid dynamic CID range (as per Erratum 3253) */
4113 if (scid < L2CAP_CID_DYN_START || scid > L2CAP_CID_DYN_END) {
4114 result = L2CAP_CR_INVALID_SCID;
4115 goto response;
4116 }
4117
4118 /* Check if we already have channel with that dcid */
4119 if (__l2cap_get_chan_by_dcid(conn, scid)) {
4120 result = L2CAP_CR_SCID_IN_USE;
4121 goto response;
4122 }
4123
4124 chan = pchan->ops->new_connection(pchan);
4125 if (!chan)
4126 goto response;
4127
4128 /* For certain devices (ex: HID mouse), support for authentication,
4129 * pairing and bonding is optional. For such devices, inorder to avoid
4130 * the ACL alive for too long after L2CAP disconnection, reset the ACL
4131 * disc_timeout back to HCI_DISCONN_TIMEOUT during L2CAP connect.
4132 */
4133 conn->hcon->disc_timeout = HCI_DISCONN_TIMEOUT;
4134
4135 bacpy(&chan->src, &conn->hcon->src);
4136 bacpy(&chan->dst, &conn->hcon->dst);
4137 chan->src_type = bdaddr_src_type(conn->hcon);
4138 chan->dst_type = bdaddr_dst_type(conn->hcon);
4139 chan->psm = psm;
4140 chan->dcid = scid;
4141 chan->local_amp_id = amp_id;
4142
4143 __l2cap_chan_add(conn, chan);
4144
4145 dcid = chan->scid;
4146
4147 __set_chan_timer(chan, chan->ops->get_sndtimeo(chan));
4148
4149 chan->ident = cmd->ident;
4150
4151 if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE) {
4152 if (l2cap_chan_check_security(chan, false)) {
4153 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) {
4154 l2cap_state_change(chan, BT_CONNECT2);
4155 result = L2CAP_CR_PEND;
4156 status = L2CAP_CS_AUTHOR_PEND;
4157 chan->ops->defer(chan);
4158 } else {
4159 /* Force pending result for AMP controllers.
4160 * The connection will succeed after the
4161 * physical link is up.
4162 */
4163 if (amp_id == AMP_ID_BREDR) {
4164 l2cap_state_change(chan, BT_CONFIG);
4165 result = L2CAP_CR_SUCCESS;
4166 } else {
4167 l2cap_state_change(chan, BT_CONNECT2);
4168 result = L2CAP_CR_PEND;
4169 }
4170 status = L2CAP_CS_NO_INFO;
4171 }
4172 } else {
4173 l2cap_state_change(chan, BT_CONNECT2);
4174 result = L2CAP_CR_PEND;
4175 status = L2CAP_CS_AUTHEN_PEND;
4176 }
4177 } else {
4178 l2cap_state_change(chan, BT_CONNECT2);
4179 result = L2CAP_CR_PEND;
4180 status = L2CAP_CS_NO_INFO;
4181 }
4182
4183response:
4184 l2cap_chan_unlock(pchan);
4185 mutex_unlock(&conn->chan_lock);
4186 l2cap_chan_put(pchan);
4187
4188sendresp:
4189 rsp.scid = cpu_to_le16(scid);
4190 rsp.dcid = cpu_to_le16(dcid);
4191 rsp.result = cpu_to_le16(result);
4192 rsp.status = cpu_to_le16(status);
4193 l2cap_send_cmd(conn, cmd->ident, rsp_code, sizeof(rsp), &rsp);
4194
4195 if (result == L2CAP_CR_PEND && status == L2CAP_CS_NO_INFO) {
4196 struct l2cap_info_req info;
4197 info.type = cpu_to_le16(L2CAP_IT_FEAT_MASK);
4198
4199 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_SENT;
4200 conn->info_ident = l2cap_get_ident(conn);
4201
4202 schedule_delayed_work(&conn->info_timer, L2CAP_INFO_TIMEOUT);
4203
4204 l2cap_send_cmd(conn, conn->info_ident, L2CAP_INFO_REQ,
4205 sizeof(info), &info);
4206 }
4207
4208 if (chan && !test_bit(CONF_REQ_SENT, &chan->conf_state) &&
4209 result == L2CAP_CR_SUCCESS) {
4210 u8 buf[128];
4211 set_bit(CONF_REQ_SENT, &chan->conf_state);
4212 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
4213 l2cap_build_conf_req(chan, buf, sizeof(buf)), buf);
4214 chan->num_conf_req++;
4215 }
4216
4217 return chan;
4218}
4219
4220static int l2cap_connect_req(struct l2cap_conn *conn,
4221 struct l2cap_cmd_hdr *cmd, u16 cmd_len, u8 *data)
4222{
4223 struct hci_dev *hdev = conn->hcon->hdev;
4224 struct hci_conn *hcon = conn->hcon;
4225
4226 if (cmd_len < sizeof(struct l2cap_conn_req))
4227 return -EPROTO;
4228
4229 hci_dev_lock(hdev);
4230 if (hci_dev_test_flag(hdev, HCI_MGMT) &&
4231 !test_and_set_bit(HCI_CONN_MGMT_CONNECTED, &hcon->flags))
4232 mgmt_device_connected(hdev, hcon, 0, NULL, 0);
4233 hci_dev_unlock(hdev);
4234
4235 l2cap_connect(conn, cmd, data, L2CAP_CONN_RSP, 0);
4236 return 0;
4237}
4238
4239static int l2cap_connect_create_rsp(struct l2cap_conn *conn,
4240 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4241 u8 *data)
4242{
4243 struct l2cap_conn_rsp *rsp = (struct l2cap_conn_rsp *) data;
4244 u16 scid, dcid, result, status;
4245 struct l2cap_chan *chan;
4246 u8 req[128];
4247 int err;
4248
4249 if (cmd_len < sizeof(*rsp))
4250 return -EPROTO;
4251
4252 scid = __le16_to_cpu(rsp->scid);
4253 dcid = __le16_to_cpu(rsp->dcid);
4254 result = __le16_to_cpu(rsp->result);
4255 status = __le16_to_cpu(rsp->status);
4256
4257 BT_DBG("dcid 0x%4.4x scid 0x%4.4x result 0x%2.2x status 0x%2.2x",
4258 dcid, scid, result, status);
4259
4260 mutex_lock(&conn->chan_lock);
4261
4262 if (scid) {
4263 chan = __l2cap_get_chan_by_scid(conn, scid);
4264 if (!chan) {
4265 err = -EBADSLT;
4266 goto unlock;
4267 }
4268 } else {
4269 chan = __l2cap_get_chan_by_ident(conn, cmd->ident);
4270 if (!chan) {
4271 err = -EBADSLT;
4272 goto unlock;
4273 }
4274 }
4275
4276 err = 0;
4277
4278 l2cap_chan_lock(chan);
4279
4280 switch (result) {
4281 case L2CAP_CR_SUCCESS:
4282 l2cap_state_change(chan, BT_CONFIG);
4283 chan->ident = 0;
4284 chan->dcid = dcid;
4285 clear_bit(CONF_CONNECT_PEND, &chan->conf_state);
4286
4287 if (test_and_set_bit(CONF_REQ_SENT, &chan->conf_state))
4288 break;
4289
4290 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
4291 l2cap_build_conf_req(chan, req, sizeof(req)), req);
4292 chan->num_conf_req++;
4293 break;
4294
4295 case L2CAP_CR_PEND:
4296 set_bit(CONF_CONNECT_PEND, &chan->conf_state);
4297 break;
4298
4299 default:
4300 l2cap_chan_del(chan, ECONNREFUSED);
4301 break;
4302 }
4303
4304 l2cap_chan_unlock(chan);
4305
4306unlock:
4307 mutex_unlock(&conn->chan_lock);
4308
4309 return err;
4310}
4311
4312static inline void set_default_fcs(struct l2cap_chan *chan)
4313{
4314 /* FCS is enabled only in ERTM or streaming mode, if one or both
4315 * sides request it.
4316 */
4317 if (chan->mode != L2CAP_MODE_ERTM && chan->mode != L2CAP_MODE_STREAMING)
4318 chan->fcs = L2CAP_FCS_NONE;
4319 else if (!test_bit(CONF_RECV_NO_FCS, &chan->conf_state))
4320 chan->fcs = L2CAP_FCS_CRC16;
4321}
4322
4323static void l2cap_send_efs_conf_rsp(struct l2cap_chan *chan, void *data,
4324 u8 ident, u16 flags)
4325{
4326 struct l2cap_conn *conn = chan->conn;
4327
4328 BT_DBG("conn %p chan %p ident %d flags 0x%4.4x", conn, chan, ident,
4329 flags);
4330
4331 clear_bit(CONF_LOC_CONF_PEND, &chan->conf_state);
4332 set_bit(CONF_OUTPUT_DONE, &chan->conf_state);
4333
4334 l2cap_send_cmd(conn, ident, L2CAP_CONF_RSP,
4335 l2cap_build_conf_rsp(chan, data,
4336 L2CAP_CONF_SUCCESS, flags), data);
4337}
4338
4339static void cmd_reject_invalid_cid(struct l2cap_conn *conn, u8 ident,
4340 u16 scid, u16 dcid)
4341{
4342 struct l2cap_cmd_rej_cid rej;
4343
4344 rej.reason = cpu_to_le16(L2CAP_REJ_INVALID_CID);
4345 rej.scid = __cpu_to_le16(scid);
4346 rej.dcid = __cpu_to_le16(dcid);
4347
4348 l2cap_send_cmd(conn, ident, L2CAP_COMMAND_REJ, sizeof(rej), &rej);
4349}
4350
4351static inline int l2cap_config_req(struct l2cap_conn *conn,
4352 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4353 u8 *data)
4354{
4355 struct l2cap_conf_req *req = (struct l2cap_conf_req *) data;
4356 u16 dcid, flags;
4357 u8 rsp[64];
4358 struct l2cap_chan *chan;
4359 int len, err = 0;
4360
4361 if (cmd_len < sizeof(*req))
4362 return -EPROTO;
4363
4364 dcid = __le16_to_cpu(req->dcid);
4365 flags = __le16_to_cpu(req->flags);
4366
4367 BT_DBG("dcid 0x%4.4x flags 0x%2.2x", dcid, flags);
4368
4369 chan = l2cap_get_chan_by_scid(conn, dcid);
4370 if (!chan) {
4371 cmd_reject_invalid_cid(conn, cmd->ident, dcid, 0);
4372 return 0;
4373 }
4374
4375 if (chan->state != BT_CONFIG && chan->state != BT_CONNECT2 &&
4376 chan->state != BT_CONNECTED) {
4377 cmd_reject_invalid_cid(conn, cmd->ident, chan->scid,
4378 chan->dcid);
4379 goto unlock;
4380 }
4381
4382 /* Reject if config buffer is too small. */
4383 len = cmd_len - sizeof(*req);
4384 if (chan->conf_len + len > sizeof(chan->conf_req)) {
4385 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP,
4386 l2cap_build_conf_rsp(chan, rsp,
4387 L2CAP_CONF_REJECT, flags), rsp);
4388 goto unlock;
4389 }
4390
4391 /* Store config. */
4392 memcpy(chan->conf_req + chan->conf_len, req->data, len);
4393 chan->conf_len += len;
4394
4395 if (flags & L2CAP_CONF_FLAG_CONTINUATION) {
4396 /* Incomplete config. Send empty response. */
4397 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP,
4398 l2cap_build_conf_rsp(chan, rsp,
4399 L2CAP_CONF_SUCCESS, flags), rsp);
4400 goto unlock;
4401 }
4402
4403 /* Complete config. */
4404 len = l2cap_parse_conf_req(chan, rsp, sizeof(rsp));
4405 if (len < 0) {
4406 l2cap_send_disconn_req(chan, ECONNRESET);
4407 goto unlock;
4408 }
4409
4410 chan->ident = cmd->ident;
4411 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP, len, rsp);
4412 chan->num_conf_rsp++;
4413
4414 /* Reset config buffer. */
4415 chan->conf_len = 0;
4416
4417 if (!test_bit(CONF_OUTPUT_DONE, &chan->conf_state))
4418 goto unlock;
4419
4420 if (test_bit(CONF_INPUT_DONE, &chan->conf_state)) {
4421 set_default_fcs(chan);
4422
4423 if (chan->mode == L2CAP_MODE_ERTM ||
4424 chan->mode == L2CAP_MODE_STREAMING)
4425 err = l2cap_ertm_init(chan);
4426
4427 if (err < 0)
4428 l2cap_send_disconn_req(chan, -err);
4429 else
4430 l2cap_chan_ready(chan);
4431
4432 goto unlock;
4433 }
4434
4435 if (!test_and_set_bit(CONF_REQ_SENT, &chan->conf_state)) {
4436 u8 buf[64];
4437 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
4438 l2cap_build_conf_req(chan, buf, sizeof(buf)), buf);
4439 chan->num_conf_req++;
4440 }
4441
4442 /* Got Conf Rsp PENDING from remote side and assume we sent
4443 Conf Rsp PENDING in the code above */
4444 if (test_bit(CONF_REM_CONF_PEND, &chan->conf_state) &&
4445 test_bit(CONF_LOC_CONF_PEND, &chan->conf_state)) {
4446
4447 /* check compatibility */
4448
4449 /* Send rsp for BR/EDR channel */
4450 if (!chan->hs_hcon)
4451 l2cap_send_efs_conf_rsp(chan, rsp, cmd->ident, flags);
4452 else
4453 chan->ident = cmd->ident;
4454 }
4455
4456unlock:
4457 l2cap_chan_unlock(chan);
4458 return err;
4459}
4460
4461static inline int l2cap_config_rsp(struct l2cap_conn *conn,
4462 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4463 u8 *data)
4464{
4465 struct l2cap_conf_rsp *rsp = (struct l2cap_conf_rsp *)data;
4466 u16 scid, flags, result;
4467 struct l2cap_chan *chan;
4468 int len = cmd_len - sizeof(*rsp);
4469 int err = 0;
4470
4471 if (cmd_len < sizeof(*rsp))
4472 return -EPROTO;
4473
4474 scid = __le16_to_cpu(rsp->scid);
4475 flags = __le16_to_cpu(rsp->flags);
4476 result = __le16_to_cpu(rsp->result);
4477
4478 BT_DBG("scid 0x%4.4x flags 0x%2.2x result 0x%2.2x len %d", scid, flags,
4479 result, len);
4480
4481 chan = l2cap_get_chan_by_scid(conn, scid);
4482 if (!chan)
4483 return 0;
4484
4485 switch (result) {
4486 case L2CAP_CONF_SUCCESS:
4487 l2cap_conf_rfc_get(chan, rsp->data, len);
4488 clear_bit(CONF_REM_CONF_PEND, &chan->conf_state);
4489 break;
4490
4491 case L2CAP_CONF_PENDING:
4492 set_bit(CONF_REM_CONF_PEND, &chan->conf_state);
4493
4494 if (test_bit(CONF_LOC_CONF_PEND, &chan->conf_state)) {
4495 char buf[64];
4496
4497 len = l2cap_parse_conf_rsp(chan, rsp->data, len,
4498 buf, sizeof(buf), &result);
4499 if (len < 0) {
4500 l2cap_send_disconn_req(chan, ECONNRESET);
4501 goto done;
4502 }
4503
4504 if (!chan->hs_hcon) {
4505 l2cap_send_efs_conf_rsp(chan, buf, cmd->ident,
4506 0);
4507 } else {
4508 if (l2cap_check_efs(chan)) {
4509 amp_create_logical_link(chan);
4510 chan->ident = cmd->ident;
4511 }
4512 }
4513 }
4514 goto done;
4515
4516 case L2CAP_CONF_UNACCEPT:
4517 if (chan->num_conf_rsp <= L2CAP_CONF_MAX_CONF_RSP) {
4518 char req[64];
4519
4520 if (len > sizeof(req) - sizeof(struct l2cap_conf_req)) {
4521 l2cap_send_disconn_req(chan, ECONNRESET);
4522 goto done;
4523 }
4524
4525 /* throw out any old stored conf requests */
4526 result = L2CAP_CONF_SUCCESS;
4527 len = l2cap_parse_conf_rsp(chan, rsp->data, len,
4528 req, sizeof(req), &result);
4529 if (len < 0) {
4530 l2cap_send_disconn_req(chan, ECONNRESET);
4531 goto done;
4532 }
4533
4534 l2cap_send_cmd(conn, l2cap_get_ident(conn),
4535 L2CAP_CONF_REQ, len, req);
4536 chan->num_conf_req++;
4537 if (result != L2CAP_CONF_SUCCESS)
4538 goto done;
4539 break;
4540 }
4541 fallthrough;
4542
4543 default:
4544 l2cap_chan_set_err(chan, ECONNRESET);
4545
4546 __set_chan_timer(chan, L2CAP_DISC_REJ_TIMEOUT);
4547 l2cap_send_disconn_req(chan, ECONNRESET);
4548 goto done;
4549 }
4550
4551 if (flags & L2CAP_CONF_FLAG_CONTINUATION)
4552 goto done;
4553
4554 set_bit(CONF_INPUT_DONE, &chan->conf_state);
4555
4556 if (test_bit(CONF_OUTPUT_DONE, &chan->conf_state)) {
4557 set_default_fcs(chan);
4558
4559 if (chan->mode == L2CAP_MODE_ERTM ||
4560 chan->mode == L2CAP_MODE_STREAMING)
4561 err = l2cap_ertm_init(chan);
4562
4563 if (err < 0)
4564 l2cap_send_disconn_req(chan, -err);
4565 else
4566 l2cap_chan_ready(chan);
4567 }
4568
4569done:
4570 l2cap_chan_unlock(chan);
4571 return err;
4572}
4573
4574static inline int l2cap_disconnect_req(struct l2cap_conn *conn,
4575 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4576 u8 *data)
4577{
4578 struct l2cap_disconn_req *req = (struct l2cap_disconn_req *) data;
4579 struct l2cap_disconn_rsp rsp;
4580 u16 dcid, scid;
4581 struct l2cap_chan *chan;
4582
4583 if (cmd_len != sizeof(*req))
4584 return -EPROTO;
4585
4586 scid = __le16_to_cpu(req->scid);
4587 dcid = __le16_to_cpu(req->dcid);
4588
4589 BT_DBG("scid 0x%4.4x dcid 0x%4.4x", scid, dcid);
4590
4591 mutex_lock(&conn->chan_lock);
4592
4593 chan = __l2cap_get_chan_by_scid(conn, dcid);
4594 if (!chan) {
4595 mutex_unlock(&conn->chan_lock);
4596 cmd_reject_invalid_cid(conn, cmd->ident, dcid, scid);
4597 return 0;
4598 }
4599
4600 l2cap_chan_hold(chan);
4601 l2cap_chan_lock(chan);
4602
4603 rsp.dcid = cpu_to_le16(chan->scid);
4604 rsp.scid = cpu_to_le16(chan->dcid);
4605 l2cap_send_cmd(conn, cmd->ident, L2CAP_DISCONN_RSP, sizeof(rsp), &rsp);
4606
4607 chan->ops->set_shutdown(chan);
4608
4609 l2cap_chan_del(chan, ECONNRESET);
4610
4611 chan->ops->close(chan);
4612
4613 l2cap_chan_unlock(chan);
4614 l2cap_chan_put(chan);
4615
4616 mutex_unlock(&conn->chan_lock);
4617
4618 return 0;
4619}
4620
4621static inline int l2cap_disconnect_rsp(struct l2cap_conn *conn,
4622 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4623 u8 *data)
4624{
4625 struct l2cap_disconn_rsp *rsp = (struct l2cap_disconn_rsp *) data;
4626 u16 dcid, scid;
4627 struct l2cap_chan *chan;
4628
4629 if (cmd_len != sizeof(*rsp))
4630 return -EPROTO;
4631
4632 scid = __le16_to_cpu(rsp->scid);
4633 dcid = __le16_to_cpu(rsp->dcid);
4634
4635 BT_DBG("dcid 0x%4.4x scid 0x%4.4x", dcid, scid);
4636
4637 mutex_lock(&conn->chan_lock);
4638
4639 chan = __l2cap_get_chan_by_scid(conn, scid);
4640 if (!chan) {
4641 mutex_unlock(&conn->chan_lock);
4642 return 0;
4643 }
4644
4645 l2cap_chan_hold(chan);
4646 l2cap_chan_lock(chan);
4647
4648 if (chan->state != BT_DISCONN) {
4649 l2cap_chan_unlock(chan);
4650 l2cap_chan_put(chan);
4651 mutex_unlock(&conn->chan_lock);
4652 return 0;
4653 }
4654
4655 l2cap_chan_del(chan, 0);
4656
4657 chan->ops->close(chan);
4658
4659 l2cap_chan_unlock(chan);
4660 l2cap_chan_put(chan);
4661
4662 mutex_unlock(&conn->chan_lock);
4663
4664 return 0;
4665}
4666
4667static inline int l2cap_information_req(struct l2cap_conn *conn,
4668 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4669 u8 *data)
4670{
4671 struct l2cap_info_req *req = (struct l2cap_info_req *) data;
4672 u16 type;
4673
4674 if (cmd_len != sizeof(*req))
4675 return -EPROTO;
4676
4677 type = __le16_to_cpu(req->type);
4678
4679 BT_DBG("type 0x%4.4x", type);
4680
4681 if (type == L2CAP_IT_FEAT_MASK) {
4682 u8 buf[8];
4683 u32 feat_mask = l2cap_feat_mask;
4684 struct l2cap_info_rsp *rsp = (struct l2cap_info_rsp *) buf;
4685 rsp->type = cpu_to_le16(L2CAP_IT_FEAT_MASK);
4686 rsp->result = cpu_to_le16(L2CAP_IR_SUCCESS);
4687 if (!disable_ertm)
4688 feat_mask |= L2CAP_FEAT_ERTM | L2CAP_FEAT_STREAMING
4689 | L2CAP_FEAT_FCS;
4690 if (conn->local_fixed_chan & L2CAP_FC_A2MP)
4691 feat_mask |= L2CAP_FEAT_EXT_FLOW
4692 | L2CAP_FEAT_EXT_WINDOW;
4693
4694 put_unaligned_le32(feat_mask, rsp->data);
4695 l2cap_send_cmd(conn, cmd->ident, L2CAP_INFO_RSP, sizeof(buf),
4696 buf);
4697 } else if (type == L2CAP_IT_FIXED_CHAN) {
4698 u8 buf[12];
4699 struct l2cap_info_rsp *rsp = (struct l2cap_info_rsp *) buf;
4700
4701 rsp->type = cpu_to_le16(L2CAP_IT_FIXED_CHAN);
4702 rsp->result = cpu_to_le16(L2CAP_IR_SUCCESS);
4703 rsp->data[0] = conn->local_fixed_chan;
4704 memset(rsp->data + 1, 0, 7);
4705 l2cap_send_cmd(conn, cmd->ident, L2CAP_INFO_RSP, sizeof(buf),
4706 buf);
4707 } else {
4708 struct l2cap_info_rsp rsp;
4709 rsp.type = cpu_to_le16(type);
4710 rsp.result = cpu_to_le16(L2CAP_IR_NOTSUPP);
4711 l2cap_send_cmd(conn, cmd->ident, L2CAP_INFO_RSP, sizeof(rsp),
4712 &rsp);
4713 }
4714
4715 return 0;
4716}
4717
4718static inline int l2cap_information_rsp(struct l2cap_conn *conn,
4719 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4720 u8 *data)
4721{
4722 struct l2cap_info_rsp *rsp = (struct l2cap_info_rsp *) data;
4723 u16 type, result;
4724
4725 if (cmd_len < sizeof(*rsp))
4726 return -EPROTO;
4727
4728 type = __le16_to_cpu(rsp->type);
4729 result = __le16_to_cpu(rsp->result);
4730
4731 BT_DBG("type 0x%4.4x result 0x%2.2x", type, result);
4732
4733 /* L2CAP Info req/rsp are unbound to channels, add extra checks */
4734 if (cmd->ident != conn->info_ident ||
4735 conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE)
4736 return 0;
4737
4738 cancel_delayed_work(&conn->info_timer);
4739
4740 if (result != L2CAP_IR_SUCCESS) {
4741 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
4742 conn->info_ident = 0;
4743
4744 l2cap_conn_start(conn);
4745
4746 return 0;
4747 }
4748
4749 switch (type) {
4750 case L2CAP_IT_FEAT_MASK:
4751 conn->feat_mask = get_unaligned_le32(rsp->data);
4752
4753 if (conn->feat_mask & L2CAP_FEAT_FIXED_CHAN) {
4754 struct l2cap_info_req req;
4755 req.type = cpu_to_le16(L2CAP_IT_FIXED_CHAN);
4756
4757 conn->info_ident = l2cap_get_ident(conn);
4758
4759 l2cap_send_cmd(conn, conn->info_ident,
4760 L2CAP_INFO_REQ, sizeof(req), &req);
4761 } else {
4762 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
4763 conn->info_ident = 0;
4764
4765 l2cap_conn_start(conn);
4766 }
4767 break;
4768
4769 case L2CAP_IT_FIXED_CHAN:
4770 conn->remote_fixed_chan = rsp->data[0];
4771 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
4772 conn->info_ident = 0;
4773
4774 l2cap_conn_start(conn);
4775 break;
4776 }
4777
4778 return 0;
4779}
4780
4781static int l2cap_create_channel_req(struct l2cap_conn *conn,
4782 struct l2cap_cmd_hdr *cmd,
4783 u16 cmd_len, void *data)
4784{
4785 struct l2cap_create_chan_req *req = data;
4786 struct l2cap_create_chan_rsp rsp;
4787 struct l2cap_chan *chan;
4788 struct hci_dev *hdev;
4789 u16 psm, scid;
4790
4791 if (cmd_len != sizeof(*req))
4792 return -EPROTO;
4793
4794 if (!(conn->local_fixed_chan & L2CAP_FC_A2MP))
4795 return -EINVAL;
4796
4797 psm = le16_to_cpu(req->psm);
4798 scid = le16_to_cpu(req->scid);
4799
4800 BT_DBG("psm 0x%2.2x, scid 0x%4.4x, amp_id %d", psm, scid, req->amp_id);
4801
4802 /* For controller id 0 make BR/EDR connection */
4803 if (req->amp_id == AMP_ID_BREDR) {
4804 l2cap_connect(conn, cmd, data, L2CAP_CREATE_CHAN_RSP,
4805 req->amp_id);
4806 return 0;
4807 }
4808
4809 /* Validate AMP controller id */
4810 hdev = hci_dev_get(req->amp_id);
4811 if (!hdev)
4812 goto error;
4813
4814 if (hdev->dev_type != HCI_AMP || !test_bit(HCI_UP, &hdev->flags)) {
4815 hci_dev_put(hdev);
4816 goto error;
4817 }
4818
4819 chan = l2cap_connect(conn, cmd, data, L2CAP_CREATE_CHAN_RSP,
4820 req->amp_id);
4821 if (chan) {
4822 struct amp_mgr *mgr = conn->hcon->amp_mgr;
4823 struct hci_conn *hs_hcon;
4824
4825 hs_hcon = hci_conn_hash_lookup_ba(hdev, AMP_LINK,
4826 &conn->hcon->dst);
4827 if (!hs_hcon) {
4828 hci_dev_put(hdev);
4829 cmd_reject_invalid_cid(conn, cmd->ident, chan->scid,
4830 chan->dcid);
4831 return 0;
4832 }
4833
4834 BT_DBG("mgr %p bredr_chan %p hs_hcon %p", mgr, chan, hs_hcon);
4835
4836 mgr->bredr_chan = chan;
4837 chan->hs_hcon = hs_hcon;
4838 chan->fcs = L2CAP_FCS_NONE;
4839 conn->mtu = hdev->block_mtu;
4840 }
4841
4842 hci_dev_put(hdev);
4843
4844 return 0;
4845
4846error:
4847 rsp.dcid = 0;
4848 rsp.scid = cpu_to_le16(scid);
4849 rsp.result = cpu_to_le16(L2CAP_CR_BAD_AMP);
4850 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
4851
4852 l2cap_send_cmd(conn, cmd->ident, L2CAP_CREATE_CHAN_RSP,
4853 sizeof(rsp), &rsp);
4854
4855 return 0;
4856}
4857
4858static void l2cap_send_move_chan_req(struct l2cap_chan *chan, u8 dest_amp_id)
4859{
4860 struct l2cap_move_chan_req req;
4861 u8 ident;
4862
4863 BT_DBG("chan %p, dest_amp_id %d", chan, dest_amp_id);
4864
4865 ident = l2cap_get_ident(chan->conn);
4866 chan->ident = ident;
4867
4868 req.icid = cpu_to_le16(chan->scid);
4869 req.dest_amp_id = dest_amp_id;
4870
4871 l2cap_send_cmd(chan->conn, ident, L2CAP_MOVE_CHAN_REQ, sizeof(req),
4872 &req);
4873
4874 __set_chan_timer(chan, L2CAP_MOVE_TIMEOUT);
4875}
4876
4877static void l2cap_send_move_chan_rsp(struct l2cap_chan *chan, u16 result)
4878{
4879 struct l2cap_move_chan_rsp rsp;
4880
4881 BT_DBG("chan %p, result 0x%4.4x", chan, result);
4882
4883 rsp.icid = cpu_to_le16(chan->dcid);
4884 rsp.result = cpu_to_le16(result);
4885
4886 l2cap_send_cmd(chan->conn, chan->ident, L2CAP_MOVE_CHAN_RSP,
4887 sizeof(rsp), &rsp);
4888}
4889
4890static void l2cap_send_move_chan_cfm(struct l2cap_chan *chan, u16 result)
4891{
4892 struct l2cap_move_chan_cfm cfm;
4893
4894 BT_DBG("chan %p, result 0x%4.4x", chan, result);
4895
4896 chan->ident = l2cap_get_ident(chan->conn);
4897
4898 cfm.icid = cpu_to_le16(chan->scid);
4899 cfm.result = cpu_to_le16(result);
4900
4901 l2cap_send_cmd(chan->conn, chan->ident, L2CAP_MOVE_CHAN_CFM,
4902 sizeof(cfm), &cfm);
4903
4904 __set_chan_timer(chan, L2CAP_MOVE_TIMEOUT);
4905}
4906
4907static void l2cap_send_move_chan_cfm_icid(struct l2cap_conn *conn, u16 icid)
4908{
4909 struct l2cap_move_chan_cfm cfm;
4910
4911 BT_DBG("conn %p, icid 0x%4.4x", conn, icid);
4912
4913 cfm.icid = cpu_to_le16(icid);
4914 cfm.result = cpu_to_le16(L2CAP_MC_UNCONFIRMED);
4915
4916 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_MOVE_CHAN_CFM,
4917 sizeof(cfm), &cfm);
4918}
4919
4920static void l2cap_send_move_chan_cfm_rsp(struct l2cap_conn *conn, u8 ident,
4921 u16 icid)
4922{
4923 struct l2cap_move_chan_cfm_rsp rsp;
4924
4925 BT_DBG("icid 0x%4.4x", icid);
4926
4927 rsp.icid = cpu_to_le16(icid);
4928 l2cap_send_cmd(conn, ident, L2CAP_MOVE_CHAN_CFM_RSP, sizeof(rsp), &rsp);
4929}
4930
4931static void __release_logical_link(struct l2cap_chan *chan)
4932{
4933 chan->hs_hchan = NULL;
4934 chan->hs_hcon = NULL;
4935
4936 /* Placeholder - release the logical link */
4937}
4938
4939static void l2cap_logical_fail(struct l2cap_chan *chan)
4940{
4941 /* Logical link setup failed */
4942 if (chan->state != BT_CONNECTED) {
4943 /* Create channel failure, disconnect */
4944 l2cap_send_disconn_req(chan, ECONNRESET);
4945 return;
4946 }
4947
4948 switch (chan->move_role) {
4949 case L2CAP_MOVE_ROLE_RESPONDER:
4950 l2cap_move_done(chan);
4951 l2cap_send_move_chan_rsp(chan, L2CAP_MR_NOT_SUPP);
4952 break;
4953 case L2CAP_MOVE_ROLE_INITIATOR:
4954 if (chan->move_state == L2CAP_MOVE_WAIT_LOGICAL_COMP ||
4955 chan->move_state == L2CAP_MOVE_WAIT_LOGICAL_CFM) {
4956 /* Remote has only sent pending or
4957 * success responses, clean up
4958 */
4959 l2cap_move_done(chan);
4960 }
4961
4962 /* Other amp move states imply that the move
4963 * has already aborted
4964 */
4965 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
4966 break;
4967 }
4968}
4969
4970static void l2cap_logical_finish_create(struct l2cap_chan *chan,
4971 struct hci_chan *hchan)
4972{
4973 struct l2cap_conf_rsp rsp;
4974
4975 chan->hs_hchan = hchan;
4976 chan->hs_hcon->l2cap_data = chan->conn;
4977
4978 l2cap_send_efs_conf_rsp(chan, &rsp, chan->ident, 0);
4979
4980 if (test_bit(CONF_INPUT_DONE, &chan->conf_state)) {
4981 int err;
4982
4983 set_default_fcs(chan);
4984
4985 err = l2cap_ertm_init(chan);
4986 if (err < 0)
4987 l2cap_send_disconn_req(chan, -err);
4988 else
4989 l2cap_chan_ready(chan);
4990 }
4991}
4992
4993static void l2cap_logical_finish_move(struct l2cap_chan *chan,
4994 struct hci_chan *hchan)
4995{
4996 chan->hs_hcon = hchan->conn;
4997 chan->hs_hcon->l2cap_data = chan->conn;
4998
4999 BT_DBG("move_state %d", chan->move_state);
5000
5001 switch (chan->move_state) {
5002 case L2CAP_MOVE_WAIT_LOGICAL_COMP:
5003 /* Move confirm will be sent after a success
5004 * response is received
5005 */
5006 chan->move_state = L2CAP_MOVE_WAIT_RSP_SUCCESS;
5007 break;
5008 case L2CAP_MOVE_WAIT_LOGICAL_CFM:
5009 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
5010 chan->move_state = L2CAP_MOVE_WAIT_LOCAL_BUSY;
5011 } else if (chan->move_role == L2CAP_MOVE_ROLE_INITIATOR) {
5012 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM_RSP;
5013 l2cap_send_move_chan_cfm(chan, L2CAP_MC_CONFIRMED);
5014 } else if (chan->move_role == L2CAP_MOVE_ROLE_RESPONDER) {
5015 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM;
5016 l2cap_send_move_chan_rsp(chan, L2CAP_MR_SUCCESS);
5017 }
5018 break;
5019 default:
5020 /* Move was not in expected state, free the channel */
5021 __release_logical_link(chan);
5022
5023 chan->move_state = L2CAP_MOVE_STABLE;
5024 }
5025}
5026
5027/* Call with chan locked */
5028void l2cap_logical_cfm(struct l2cap_chan *chan, struct hci_chan *hchan,
5029 u8 status)
5030{
5031 BT_DBG("chan %p, hchan %p, status %d", chan, hchan, status);
5032
5033 if (status) {
5034 l2cap_logical_fail(chan);
5035 __release_logical_link(chan);
5036 return;
5037 }
5038
5039 if (chan->state != BT_CONNECTED) {
5040 /* Ignore logical link if channel is on BR/EDR */
5041 if (chan->local_amp_id != AMP_ID_BREDR)
5042 l2cap_logical_finish_create(chan, hchan);
5043 } else {
5044 l2cap_logical_finish_move(chan, hchan);
5045 }
5046}
5047
5048void l2cap_move_start(struct l2cap_chan *chan)
5049{
5050 BT_DBG("chan %p", chan);
5051
5052 if (chan->local_amp_id == AMP_ID_BREDR) {
5053 if (chan->chan_policy != BT_CHANNEL_POLICY_AMP_PREFERRED)
5054 return;
5055 chan->move_role = L2CAP_MOVE_ROLE_INITIATOR;
5056 chan->move_state = L2CAP_MOVE_WAIT_PREPARE;
5057 /* Placeholder - start physical link setup */
5058 } else {
5059 chan->move_role = L2CAP_MOVE_ROLE_INITIATOR;
5060 chan->move_state = L2CAP_MOVE_WAIT_RSP_SUCCESS;
5061 chan->move_id = 0;
5062 l2cap_move_setup(chan);
5063 l2cap_send_move_chan_req(chan, 0);
5064 }
5065}
5066
5067static void l2cap_do_create(struct l2cap_chan *chan, int result,
5068 u8 local_amp_id, u8 remote_amp_id)
5069{
5070 BT_DBG("chan %p state %s %u -> %u", chan, state_to_string(chan->state),
5071 local_amp_id, remote_amp_id);
5072
5073 chan->fcs = L2CAP_FCS_NONE;
5074
5075 /* Outgoing channel on AMP */
5076 if (chan->state == BT_CONNECT) {
5077 if (result == L2CAP_CR_SUCCESS) {
5078 chan->local_amp_id = local_amp_id;
5079 l2cap_send_create_chan_req(chan, remote_amp_id);
5080 } else {
5081 /* Revert to BR/EDR connect */
5082 l2cap_send_conn_req(chan);
5083 }
5084
5085 return;
5086 }
5087
5088 /* Incoming channel on AMP */
5089 if (__l2cap_no_conn_pending(chan)) {
5090 struct l2cap_conn_rsp rsp;
5091 char buf[128];
5092 rsp.scid = cpu_to_le16(chan->dcid);
5093 rsp.dcid = cpu_to_le16(chan->scid);
5094
5095 if (result == L2CAP_CR_SUCCESS) {
5096 /* Send successful response */
5097 rsp.result = cpu_to_le16(L2CAP_CR_SUCCESS);
5098 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
5099 } else {
5100 /* Send negative response */
5101 rsp.result = cpu_to_le16(L2CAP_CR_NO_MEM);
5102 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
5103 }
5104
5105 l2cap_send_cmd(chan->conn, chan->ident, L2CAP_CREATE_CHAN_RSP,
5106 sizeof(rsp), &rsp);
5107
5108 if (result == L2CAP_CR_SUCCESS) {
5109 l2cap_state_change(chan, BT_CONFIG);
5110 set_bit(CONF_REQ_SENT, &chan->conf_state);
5111 l2cap_send_cmd(chan->conn, l2cap_get_ident(chan->conn),
5112 L2CAP_CONF_REQ,
5113 l2cap_build_conf_req(chan, buf, sizeof(buf)), buf);
5114 chan->num_conf_req++;
5115 }
5116 }
5117}
5118
5119static void l2cap_do_move_initiate(struct l2cap_chan *chan, u8 local_amp_id,
5120 u8 remote_amp_id)
5121{
5122 l2cap_move_setup(chan);
5123 chan->move_id = local_amp_id;
5124 chan->move_state = L2CAP_MOVE_WAIT_RSP;
5125
5126 l2cap_send_move_chan_req(chan, remote_amp_id);
5127}
5128
5129static void l2cap_do_move_respond(struct l2cap_chan *chan, int result)
5130{
5131 struct hci_chan *hchan = NULL;
5132
5133 /* Placeholder - get hci_chan for logical link */
5134
5135 if (hchan) {
5136 if (hchan->state == BT_CONNECTED) {
5137 /* Logical link is ready to go */
5138 chan->hs_hcon = hchan->conn;
5139 chan->hs_hcon->l2cap_data = chan->conn;
5140 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM;
5141 l2cap_send_move_chan_rsp(chan, L2CAP_MR_SUCCESS);
5142
5143 l2cap_logical_cfm(chan, hchan, L2CAP_MR_SUCCESS);
5144 } else {
5145 /* Wait for logical link to be ready */
5146 chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_CFM;
5147 }
5148 } else {
5149 /* Logical link not available */
5150 l2cap_send_move_chan_rsp(chan, L2CAP_MR_NOT_ALLOWED);
5151 }
5152}
5153
5154static void l2cap_do_move_cancel(struct l2cap_chan *chan, int result)
5155{
5156 if (chan->move_role == L2CAP_MOVE_ROLE_RESPONDER) {
5157 u8 rsp_result;
5158 if (result == -EINVAL)
5159 rsp_result = L2CAP_MR_BAD_ID;
5160 else
5161 rsp_result = L2CAP_MR_NOT_ALLOWED;
5162
5163 l2cap_send_move_chan_rsp(chan, rsp_result);
5164 }
5165
5166 chan->move_role = L2CAP_MOVE_ROLE_NONE;
5167 chan->move_state = L2CAP_MOVE_STABLE;
5168
5169 /* Restart data transmission */
5170 l2cap_ertm_send(chan);
5171}
5172
5173/* Invoke with locked chan */
5174void __l2cap_physical_cfm(struct l2cap_chan *chan, int result)
5175{
5176 u8 local_amp_id = chan->local_amp_id;
5177 u8 remote_amp_id = chan->remote_amp_id;
5178
5179 BT_DBG("chan %p, result %d, local_amp_id %d, remote_amp_id %d",
5180 chan, result, local_amp_id, remote_amp_id);
5181
5182 if (chan->state == BT_DISCONN || chan->state == BT_CLOSED)
5183 return;
5184
5185 if (chan->state != BT_CONNECTED) {
5186 l2cap_do_create(chan, result, local_amp_id, remote_amp_id);
5187 } else if (result != L2CAP_MR_SUCCESS) {
5188 l2cap_do_move_cancel(chan, result);
5189 } else {
5190 switch (chan->move_role) {
5191 case L2CAP_MOVE_ROLE_INITIATOR:
5192 l2cap_do_move_initiate(chan, local_amp_id,
5193 remote_amp_id);
5194 break;
5195 case L2CAP_MOVE_ROLE_RESPONDER:
5196 l2cap_do_move_respond(chan, result);
5197 break;
5198 default:
5199 l2cap_do_move_cancel(chan, result);
5200 break;
5201 }
5202 }
5203}
5204
5205static inline int l2cap_move_channel_req(struct l2cap_conn *conn,
5206 struct l2cap_cmd_hdr *cmd,
5207 u16 cmd_len, void *data)
5208{
5209 struct l2cap_move_chan_req *req = data;
5210 struct l2cap_move_chan_rsp rsp;
5211 struct l2cap_chan *chan;
5212 u16 icid = 0;
5213 u16 result = L2CAP_MR_NOT_ALLOWED;
5214
5215 if (cmd_len != sizeof(*req))
5216 return -EPROTO;
5217
5218 icid = le16_to_cpu(req->icid);
5219
5220 BT_DBG("icid 0x%4.4x, dest_amp_id %d", icid, req->dest_amp_id);
5221
5222 if (!(conn->local_fixed_chan & L2CAP_FC_A2MP))
5223 return -EINVAL;
5224
5225 chan = l2cap_get_chan_by_dcid(conn, icid);
5226 if (!chan) {
5227 rsp.icid = cpu_to_le16(icid);
5228 rsp.result = cpu_to_le16(L2CAP_MR_NOT_ALLOWED);
5229 l2cap_send_cmd(conn, cmd->ident, L2CAP_MOVE_CHAN_RSP,
5230 sizeof(rsp), &rsp);
5231 return 0;
5232 }
5233
5234 chan->ident = cmd->ident;
5235
5236 if (chan->scid < L2CAP_CID_DYN_START ||
5237 chan->chan_policy == BT_CHANNEL_POLICY_BREDR_ONLY ||
5238 (chan->mode != L2CAP_MODE_ERTM &&
5239 chan->mode != L2CAP_MODE_STREAMING)) {
5240 result = L2CAP_MR_NOT_ALLOWED;
5241 goto send_move_response;
5242 }
5243
5244 if (chan->local_amp_id == req->dest_amp_id) {
5245 result = L2CAP_MR_SAME_ID;
5246 goto send_move_response;
5247 }
5248
5249 if (req->dest_amp_id != AMP_ID_BREDR) {
5250 struct hci_dev *hdev;
5251 hdev = hci_dev_get(req->dest_amp_id);
5252 if (!hdev || hdev->dev_type != HCI_AMP ||
5253 !test_bit(HCI_UP, &hdev->flags)) {
5254 if (hdev)
5255 hci_dev_put(hdev);
5256
5257 result = L2CAP_MR_BAD_ID;
5258 goto send_move_response;
5259 }
5260 hci_dev_put(hdev);
5261 }
5262
5263 /* Detect a move collision. Only send a collision response
5264 * if this side has "lost", otherwise proceed with the move.
5265 * The winner has the larger bd_addr.
5266 */
5267 if ((__chan_is_moving(chan) ||
5268 chan->move_role != L2CAP_MOVE_ROLE_NONE) &&
5269 bacmp(&conn->hcon->src, &conn->hcon->dst) > 0) {
5270 result = L2CAP_MR_COLLISION;
5271 goto send_move_response;
5272 }
5273
5274 chan->move_role = L2CAP_MOVE_ROLE_RESPONDER;
5275 l2cap_move_setup(chan);
5276 chan->move_id = req->dest_amp_id;
5277
5278 if (req->dest_amp_id == AMP_ID_BREDR) {
5279 /* Moving to BR/EDR */
5280 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
5281 chan->move_state = L2CAP_MOVE_WAIT_LOCAL_BUSY;
5282 result = L2CAP_MR_PEND;
5283 } else {
5284 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM;
5285 result = L2CAP_MR_SUCCESS;
5286 }
5287 } else {
5288 chan->move_state = L2CAP_MOVE_WAIT_PREPARE;
5289 /* Placeholder - uncomment when amp functions are available */
5290 /*amp_accept_physical(chan, req->dest_amp_id);*/
5291 result = L2CAP_MR_PEND;
5292 }
5293
5294send_move_response:
5295 l2cap_send_move_chan_rsp(chan, result);
5296
5297 l2cap_chan_unlock(chan);
5298
5299 return 0;
5300}
5301
5302static void l2cap_move_continue(struct l2cap_conn *conn, u16 icid, u16 result)
5303{
5304 struct l2cap_chan *chan;
5305 struct hci_chan *hchan = NULL;
5306
5307 chan = l2cap_get_chan_by_scid(conn, icid);
5308 if (!chan) {
5309 l2cap_send_move_chan_cfm_icid(conn, icid);
5310 return;
5311 }
5312
5313 __clear_chan_timer(chan);
5314 if (result == L2CAP_MR_PEND)
5315 __set_chan_timer(chan, L2CAP_MOVE_ERTX_TIMEOUT);
5316
5317 switch (chan->move_state) {
5318 case L2CAP_MOVE_WAIT_LOGICAL_COMP:
5319 /* Move confirm will be sent when logical link
5320 * is complete.
5321 */
5322 chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_CFM;
5323 break;
5324 case L2CAP_MOVE_WAIT_RSP_SUCCESS:
5325 if (result == L2CAP_MR_PEND) {
5326 break;
5327 } else if (test_bit(CONN_LOCAL_BUSY,
5328 &chan->conn_state)) {
5329 chan->move_state = L2CAP_MOVE_WAIT_LOCAL_BUSY;
5330 } else {
5331 /* Logical link is up or moving to BR/EDR,
5332 * proceed with move
5333 */
5334 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM_RSP;
5335 l2cap_send_move_chan_cfm(chan, L2CAP_MC_CONFIRMED);
5336 }
5337 break;
5338 case L2CAP_MOVE_WAIT_RSP:
5339 /* Moving to AMP */
5340 if (result == L2CAP_MR_SUCCESS) {
5341 /* Remote is ready, send confirm immediately
5342 * after logical link is ready
5343 */
5344 chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_CFM;
5345 } else {
5346 /* Both logical link and move success
5347 * are required to confirm
5348 */
5349 chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_COMP;
5350 }
5351
5352 /* Placeholder - get hci_chan for logical link */
5353 if (!hchan) {
5354 /* Logical link not available */
5355 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
5356 break;
5357 }
5358
5359 /* If the logical link is not yet connected, do not
5360 * send confirmation.
5361 */
5362 if (hchan->state != BT_CONNECTED)
5363 break;
5364
5365 /* Logical link is already ready to go */
5366
5367 chan->hs_hcon = hchan->conn;
5368 chan->hs_hcon->l2cap_data = chan->conn;
5369
5370 if (result == L2CAP_MR_SUCCESS) {
5371 /* Can confirm now */
5372 l2cap_send_move_chan_cfm(chan, L2CAP_MC_CONFIRMED);
5373 } else {
5374 /* Now only need move success
5375 * to confirm
5376 */
5377 chan->move_state = L2CAP_MOVE_WAIT_RSP_SUCCESS;
5378 }
5379
5380 l2cap_logical_cfm(chan, hchan, L2CAP_MR_SUCCESS);
5381 break;
5382 default:
5383 /* Any other amp move state means the move failed. */
5384 chan->move_id = chan->local_amp_id;
5385 l2cap_move_done(chan);
5386 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
5387 }
5388
5389 l2cap_chan_unlock(chan);
5390}
5391
5392static void l2cap_move_fail(struct l2cap_conn *conn, u8 ident, u16 icid,
5393 u16 result)
5394{
5395 struct l2cap_chan *chan;
5396
5397 chan = l2cap_get_chan_by_ident(conn, ident);
5398 if (!chan) {
5399 /* Could not locate channel, icid is best guess */
5400 l2cap_send_move_chan_cfm_icid(conn, icid);
5401 return;
5402 }
5403
5404 __clear_chan_timer(chan);
5405
5406 if (chan->move_role == L2CAP_MOVE_ROLE_INITIATOR) {
5407 if (result == L2CAP_MR_COLLISION) {
5408 chan->move_role = L2CAP_MOVE_ROLE_RESPONDER;
5409 } else {
5410 /* Cleanup - cancel move */
5411 chan->move_id = chan->local_amp_id;
5412 l2cap_move_done(chan);
5413 }
5414 }
5415
5416 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
5417
5418 l2cap_chan_unlock(chan);
5419}
5420
5421static int l2cap_move_channel_rsp(struct l2cap_conn *conn,
5422 struct l2cap_cmd_hdr *cmd,
5423 u16 cmd_len, void *data)
5424{
5425 struct l2cap_move_chan_rsp *rsp = data;
5426 u16 icid, result;
5427
5428 if (cmd_len != sizeof(*rsp))
5429 return -EPROTO;
5430
5431 icid = le16_to_cpu(rsp->icid);
5432 result = le16_to_cpu(rsp->result);
5433
5434 BT_DBG("icid 0x%4.4x, result 0x%4.4x", icid, result);
5435
5436 if (result == L2CAP_MR_SUCCESS || result == L2CAP_MR_PEND)
5437 l2cap_move_continue(conn, icid, result);
5438 else
5439 l2cap_move_fail(conn, cmd->ident, icid, result);
5440
5441 return 0;
5442}
5443
5444static int l2cap_move_channel_confirm(struct l2cap_conn *conn,
5445 struct l2cap_cmd_hdr *cmd,
5446 u16 cmd_len, void *data)
5447{
5448 struct l2cap_move_chan_cfm *cfm = data;
5449 struct l2cap_chan *chan;
5450 u16 icid, result;
5451
5452 if (cmd_len != sizeof(*cfm))
5453 return -EPROTO;
5454
5455 icid = le16_to_cpu(cfm->icid);
5456 result = le16_to_cpu(cfm->result);
5457
5458 BT_DBG("icid 0x%4.4x, result 0x%4.4x", icid, result);
5459
5460 chan = l2cap_get_chan_by_dcid(conn, icid);
5461 if (!chan) {
5462 /* Spec requires a response even if the icid was not found */
5463 l2cap_send_move_chan_cfm_rsp(conn, cmd->ident, icid);
5464 return 0;
5465 }
5466
5467 if (chan->move_state == L2CAP_MOVE_WAIT_CONFIRM) {
5468 if (result == L2CAP_MC_CONFIRMED) {
5469 chan->local_amp_id = chan->move_id;
5470 if (chan->local_amp_id == AMP_ID_BREDR)
5471 __release_logical_link(chan);
5472 } else {
5473 chan->move_id = chan->local_amp_id;
5474 }
5475
5476 l2cap_move_done(chan);
5477 }
5478
5479 l2cap_send_move_chan_cfm_rsp(conn, cmd->ident, icid);
5480
5481 l2cap_chan_unlock(chan);
5482
5483 return 0;
5484}
5485
5486static inline int l2cap_move_channel_confirm_rsp(struct l2cap_conn *conn,
5487 struct l2cap_cmd_hdr *cmd,
5488 u16 cmd_len, void *data)
5489{
5490 struct l2cap_move_chan_cfm_rsp *rsp = data;
5491 struct l2cap_chan *chan;
5492 u16 icid;
5493
5494 if (cmd_len != sizeof(*rsp))
5495 return -EPROTO;
5496
5497 icid = le16_to_cpu(rsp->icid);
5498
5499 BT_DBG("icid 0x%4.4x", icid);
5500
5501 chan = l2cap_get_chan_by_scid(conn, icid);
5502 if (!chan)
5503 return 0;
5504
5505 __clear_chan_timer(chan);
5506
5507 if (chan->move_state == L2CAP_MOVE_WAIT_CONFIRM_RSP) {
5508 chan->local_amp_id = chan->move_id;
5509
5510 if (chan->local_amp_id == AMP_ID_BREDR && chan->hs_hchan)
5511 __release_logical_link(chan);
5512
5513 l2cap_move_done(chan);
5514 }
5515
5516 l2cap_chan_unlock(chan);
5517
5518 return 0;
5519}
5520
5521static inline int l2cap_conn_param_update_req(struct l2cap_conn *conn,
5522 struct l2cap_cmd_hdr *cmd,
5523 u16 cmd_len, u8 *data)
5524{
5525 struct hci_conn *hcon = conn->hcon;
5526 struct l2cap_conn_param_update_req *req;
5527 struct l2cap_conn_param_update_rsp rsp;
5528 u16 min, max, latency, to_multiplier;
5529 int err;
5530
5531 if (hcon->role != HCI_ROLE_MASTER)
5532 return -EINVAL;
5533
5534 if (cmd_len != sizeof(struct l2cap_conn_param_update_req))
5535 return -EPROTO;
5536
5537 req = (struct l2cap_conn_param_update_req *) data;
5538 min = __le16_to_cpu(req->min);
5539 max = __le16_to_cpu(req->max);
5540 latency = __le16_to_cpu(req->latency);
5541 to_multiplier = __le16_to_cpu(req->to_multiplier);
5542
5543 BT_DBG("min 0x%4.4x max 0x%4.4x latency: 0x%4.4x Timeout: 0x%4.4x",
5544 min, max, latency, to_multiplier);
5545
5546 memset(&rsp, 0, sizeof(rsp));
5547
5548 err = hci_check_conn_params(min, max, latency, to_multiplier);
5549 if (err)
5550 rsp.result = cpu_to_le16(L2CAP_CONN_PARAM_REJECTED);
5551 else
5552 rsp.result = cpu_to_le16(L2CAP_CONN_PARAM_ACCEPTED);
5553
5554 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONN_PARAM_UPDATE_RSP,
5555 sizeof(rsp), &rsp);
5556
5557 if (!err) {
5558 u8 store_hint;
5559
5560 store_hint = hci_le_conn_update(hcon, min, max, latency,
5561 to_multiplier);
5562 mgmt_new_conn_param(hcon->hdev, &hcon->dst, hcon->dst_type,
5563 store_hint, min, max, latency,
5564 to_multiplier);
5565
5566 }
5567
5568 return 0;
5569}
5570
5571static int l2cap_le_connect_rsp(struct l2cap_conn *conn,
5572 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5573 u8 *data)
5574{
5575 struct l2cap_le_conn_rsp *rsp = (struct l2cap_le_conn_rsp *) data;
5576 struct hci_conn *hcon = conn->hcon;
5577 u16 dcid, mtu, mps, credits, result;
5578 struct l2cap_chan *chan;
5579 int err, sec_level;
5580
5581 if (cmd_len < sizeof(*rsp))
5582 return -EPROTO;
5583
5584 dcid = __le16_to_cpu(rsp->dcid);
5585 mtu = __le16_to_cpu(rsp->mtu);
5586 mps = __le16_to_cpu(rsp->mps);
5587 credits = __le16_to_cpu(rsp->credits);
5588 result = __le16_to_cpu(rsp->result);
5589
5590 if (result == L2CAP_CR_LE_SUCCESS && (mtu < 23 || mps < 23 ||
5591 dcid < L2CAP_CID_DYN_START ||
5592 dcid > L2CAP_CID_LE_DYN_END))
5593 return -EPROTO;
5594
5595 BT_DBG("dcid 0x%4.4x mtu %u mps %u credits %u result 0x%2.2x",
5596 dcid, mtu, mps, credits, result);
5597
5598 mutex_lock(&conn->chan_lock);
5599
5600 chan = __l2cap_get_chan_by_ident(conn, cmd->ident);
5601 if (!chan) {
5602 err = -EBADSLT;
5603 goto unlock;
5604 }
5605
5606 err = 0;
5607
5608 l2cap_chan_lock(chan);
5609
5610 switch (result) {
5611 case L2CAP_CR_LE_SUCCESS:
5612 if (__l2cap_get_chan_by_dcid(conn, dcid)) {
5613 err = -EBADSLT;
5614 break;
5615 }
5616
5617 chan->ident = 0;
5618 chan->dcid = dcid;
5619 chan->omtu = mtu;
5620 chan->remote_mps = mps;
5621 chan->tx_credits = credits;
5622 l2cap_chan_ready(chan);
5623 break;
5624
5625 case L2CAP_CR_LE_AUTHENTICATION:
5626 case L2CAP_CR_LE_ENCRYPTION:
5627 /* If we already have MITM protection we can't do
5628 * anything.
5629 */
5630 if (hcon->sec_level > BT_SECURITY_MEDIUM) {
5631 l2cap_chan_del(chan, ECONNREFUSED);
5632 break;
5633 }
5634
5635 sec_level = hcon->sec_level + 1;
5636 if (chan->sec_level < sec_level)
5637 chan->sec_level = sec_level;
5638
5639 /* We'll need to send a new Connect Request */
5640 clear_bit(FLAG_LE_CONN_REQ_SENT, &chan->flags);
5641
5642 smp_conn_security(hcon, chan->sec_level);
5643 break;
5644
5645 default:
5646 l2cap_chan_del(chan, ECONNREFUSED);
5647 break;
5648 }
5649
5650 l2cap_chan_unlock(chan);
5651
5652unlock:
5653 mutex_unlock(&conn->chan_lock);
5654
5655 return err;
5656}
5657
5658static inline int l2cap_bredr_sig_cmd(struct l2cap_conn *conn,
5659 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5660 u8 *data)
5661{
5662 int err = 0;
5663
5664 switch (cmd->code) {
5665 case L2CAP_COMMAND_REJ:
5666 l2cap_command_rej(conn, cmd, cmd_len, data);
5667 break;
5668
5669 case L2CAP_CONN_REQ:
5670 err = l2cap_connect_req(conn, cmd, cmd_len, data);
5671 break;
5672
5673 case L2CAP_CONN_RSP:
5674 case L2CAP_CREATE_CHAN_RSP:
5675 l2cap_connect_create_rsp(conn, cmd, cmd_len, data);
5676 break;
5677
5678 case L2CAP_CONF_REQ:
5679 err = l2cap_config_req(conn, cmd, cmd_len, data);
5680 break;
5681
5682 case L2CAP_CONF_RSP:
5683 l2cap_config_rsp(conn, cmd, cmd_len, data);
5684 break;
5685
5686 case L2CAP_DISCONN_REQ:
5687 err = l2cap_disconnect_req(conn, cmd, cmd_len, data);
5688 break;
5689
5690 case L2CAP_DISCONN_RSP:
5691 l2cap_disconnect_rsp(conn, cmd, cmd_len, data);
5692 break;
5693
5694 case L2CAP_ECHO_REQ:
5695 l2cap_send_cmd(conn, cmd->ident, L2CAP_ECHO_RSP, cmd_len, data);
5696 break;
5697
5698 case L2CAP_ECHO_RSP:
5699 break;
5700
5701 case L2CAP_INFO_REQ:
5702 err = l2cap_information_req(conn, cmd, cmd_len, data);
5703 break;
5704
5705 case L2CAP_INFO_RSP:
5706 l2cap_information_rsp(conn, cmd, cmd_len, data);
5707 break;
5708
5709 case L2CAP_CREATE_CHAN_REQ:
5710 err = l2cap_create_channel_req(conn, cmd, cmd_len, data);
5711 break;
5712
5713 case L2CAP_MOVE_CHAN_REQ:
5714 err = l2cap_move_channel_req(conn, cmd, cmd_len, data);
5715 break;
5716
5717 case L2CAP_MOVE_CHAN_RSP:
5718 l2cap_move_channel_rsp(conn, cmd, cmd_len, data);
5719 break;
5720
5721 case L2CAP_MOVE_CHAN_CFM:
5722 err = l2cap_move_channel_confirm(conn, cmd, cmd_len, data);
5723 break;
5724
5725 case L2CAP_MOVE_CHAN_CFM_RSP:
5726 l2cap_move_channel_confirm_rsp(conn, cmd, cmd_len, data);
5727 break;
5728
5729 default:
5730 BT_ERR("Unknown BR/EDR signaling command 0x%2.2x", cmd->code);
5731 err = -EINVAL;
5732 break;
5733 }
5734
5735 return err;
5736}
5737
5738static int l2cap_le_connect_req(struct l2cap_conn *conn,
5739 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5740 u8 *data)
5741{
5742 struct l2cap_le_conn_req *req = (struct l2cap_le_conn_req *) data;
5743 struct l2cap_le_conn_rsp rsp;
5744 struct l2cap_chan *chan, *pchan;
5745 u16 dcid, scid, credits, mtu, mps;
5746 __le16 psm;
5747 u8 result;
5748
5749 if (cmd_len != sizeof(*req))
5750 return -EPROTO;
5751
5752 scid = __le16_to_cpu(req->scid);
5753 mtu = __le16_to_cpu(req->mtu);
5754 mps = __le16_to_cpu(req->mps);
5755 psm = req->psm;
5756 dcid = 0;
5757 credits = 0;
5758
5759 if (mtu < 23 || mps < 23)
5760 return -EPROTO;
5761
5762 BT_DBG("psm 0x%2.2x scid 0x%4.4x mtu %u mps %u", __le16_to_cpu(psm),
5763 scid, mtu, mps);
5764
5765 /* Check if we have socket listening on psm */
5766 pchan = l2cap_global_chan_by_psm(BT_LISTEN, psm, &conn->hcon->src,
5767 &conn->hcon->dst, LE_LINK);
5768 if (!pchan) {
5769 result = L2CAP_CR_LE_BAD_PSM;
5770 chan = NULL;
5771 goto response;
5772 }
5773
5774 mutex_lock(&conn->chan_lock);
5775 l2cap_chan_lock(pchan);
5776
5777 if (!smp_sufficient_security(conn->hcon, pchan->sec_level,
5778 SMP_ALLOW_STK)) {
5779 result = L2CAP_CR_LE_AUTHENTICATION;
5780 chan = NULL;
5781 goto response_unlock;
5782 }
5783
5784 /* Check for valid dynamic CID range */
5785 if (scid < L2CAP_CID_DYN_START || scid > L2CAP_CID_LE_DYN_END) {
5786 result = L2CAP_CR_LE_INVALID_SCID;
5787 chan = NULL;
5788 goto response_unlock;
5789 }
5790
5791 /* Check if we already have channel with that dcid */
5792 if (__l2cap_get_chan_by_dcid(conn, scid)) {
5793 result = L2CAP_CR_LE_SCID_IN_USE;
5794 chan = NULL;
5795 goto response_unlock;
5796 }
5797
5798 chan = pchan->ops->new_connection(pchan);
5799 if (!chan) {
5800 result = L2CAP_CR_LE_NO_MEM;
5801 goto response_unlock;
5802 }
5803
5804 bacpy(&chan->src, &conn->hcon->src);
5805 bacpy(&chan->dst, &conn->hcon->dst);
5806 chan->src_type = bdaddr_src_type(conn->hcon);
5807 chan->dst_type = bdaddr_dst_type(conn->hcon);
5808 chan->psm = psm;
5809 chan->dcid = scid;
5810 chan->omtu = mtu;
5811 chan->remote_mps = mps;
5812
5813 __l2cap_chan_add(conn, chan);
5814
5815 l2cap_le_flowctl_init(chan, __le16_to_cpu(req->credits));
5816
5817 dcid = chan->scid;
5818 credits = chan->rx_credits;
5819
5820 __set_chan_timer(chan, chan->ops->get_sndtimeo(chan));
5821
5822 chan->ident = cmd->ident;
5823
5824 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) {
5825 l2cap_state_change(chan, BT_CONNECT2);
5826 /* The following result value is actually not defined
5827 * for LE CoC but we use it to let the function know
5828 * that it should bail out after doing its cleanup
5829 * instead of sending a response.
5830 */
5831 result = L2CAP_CR_PEND;
5832 chan->ops->defer(chan);
5833 } else {
5834 l2cap_chan_ready(chan);
5835 result = L2CAP_CR_LE_SUCCESS;
5836 }
5837
5838response_unlock:
5839 l2cap_chan_unlock(pchan);
5840 mutex_unlock(&conn->chan_lock);
5841 l2cap_chan_put(pchan);
5842
5843 if (result == L2CAP_CR_PEND)
5844 return 0;
5845
5846response:
5847 if (chan) {
5848 rsp.mtu = cpu_to_le16(chan->imtu);
5849 rsp.mps = cpu_to_le16(chan->mps);
5850 } else {
5851 rsp.mtu = 0;
5852 rsp.mps = 0;
5853 }
5854
5855 rsp.dcid = cpu_to_le16(dcid);
5856 rsp.credits = cpu_to_le16(credits);
5857 rsp.result = cpu_to_le16(result);
5858
5859 l2cap_send_cmd(conn, cmd->ident, L2CAP_LE_CONN_RSP, sizeof(rsp), &rsp);
5860
5861 return 0;
5862}
5863
5864static inline int l2cap_le_credits(struct l2cap_conn *conn,
5865 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5866 u8 *data)
5867{
5868 struct l2cap_le_credits *pkt;
5869 struct l2cap_chan *chan;
5870 u16 cid, credits, max_credits;
5871
5872 if (cmd_len != sizeof(*pkt))
5873 return -EPROTO;
5874
5875 pkt = (struct l2cap_le_credits *) data;
5876 cid = __le16_to_cpu(pkt->cid);
5877 credits = __le16_to_cpu(pkt->credits);
5878
5879 BT_DBG("cid 0x%4.4x credits 0x%4.4x", cid, credits);
5880
5881 chan = l2cap_get_chan_by_dcid(conn, cid);
5882 if (!chan)
5883 return -EBADSLT;
5884
5885 max_credits = LE_FLOWCTL_MAX_CREDITS - chan->tx_credits;
5886 if (credits > max_credits) {
5887 BT_ERR("LE credits overflow");
5888 l2cap_send_disconn_req(chan, ECONNRESET);
5889 l2cap_chan_unlock(chan);
5890
5891 /* Return 0 so that we don't trigger an unnecessary
5892 * command reject packet.
5893 */
5894 return 0;
5895 }
5896
5897 chan->tx_credits += credits;
5898
5899 /* Resume sending */
5900 l2cap_le_flowctl_send(chan);
5901
5902 if (chan->tx_credits)
5903 chan->ops->resume(chan);
5904
5905 l2cap_chan_unlock(chan);
5906
5907 return 0;
5908}
5909
5910static inline int l2cap_ecred_conn_req(struct l2cap_conn *conn,
5911 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5912 u8 *data)
5913{
5914 struct l2cap_ecred_conn_req *req = (void *) data;
5915 struct {
5916 struct l2cap_ecred_conn_rsp rsp;
5917 __le16 dcid[5];
5918 } __packed pdu;
5919 struct l2cap_chan *chan, *pchan;
5920 u16 mtu, mps;
5921 __le16 psm;
5922 u8 result, len = 0;
5923 int i, num_scid;
5924 bool defer = false;
5925
5926 if (!enable_ecred)
5927 return -EINVAL;
5928
5929 if (cmd_len < sizeof(*req) || (cmd_len - sizeof(*req)) % sizeof(u16)) {
5930 result = L2CAP_CR_LE_INVALID_PARAMS;
5931 goto response;
5932 }
5933
5934 mtu = __le16_to_cpu(req->mtu);
5935 mps = __le16_to_cpu(req->mps);
5936
5937 if (mtu < L2CAP_ECRED_MIN_MTU || mps < L2CAP_ECRED_MIN_MPS) {
5938 result = L2CAP_CR_LE_UNACCEPT_PARAMS;
5939 goto response;
5940 }
5941
5942 psm = req->psm;
5943
5944 BT_DBG("psm 0x%2.2x mtu %u mps %u", __le16_to_cpu(psm), mtu, mps);
5945
5946 memset(&pdu, 0, sizeof(pdu));
5947
5948 /* Check if we have socket listening on psm */
5949 pchan = l2cap_global_chan_by_psm(BT_LISTEN, psm, &conn->hcon->src,
5950 &conn->hcon->dst, LE_LINK);
5951 if (!pchan) {
5952 result = L2CAP_CR_LE_BAD_PSM;
5953 goto response;
5954 }
5955
5956 mutex_lock(&conn->chan_lock);
5957 l2cap_chan_lock(pchan);
5958
5959 if (!smp_sufficient_security(conn->hcon, pchan->sec_level,
5960 SMP_ALLOW_STK)) {
5961 result = L2CAP_CR_LE_AUTHENTICATION;
5962 goto unlock;
5963 }
5964
5965 result = L2CAP_CR_LE_SUCCESS;
5966 cmd_len -= sizeof(*req);
5967 num_scid = cmd_len / sizeof(u16);
5968
5969 for (i = 0; i < num_scid; i++) {
5970 u16 scid = __le16_to_cpu(req->scid[i]);
5971
5972 BT_DBG("scid[%d] 0x%4.4x", i, scid);
5973
5974 pdu.dcid[i] = 0x0000;
5975 len += sizeof(*pdu.dcid);
5976
5977 /* Check for valid dynamic CID range */
5978 if (scid < L2CAP_CID_DYN_START || scid > L2CAP_CID_LE_DYN_END) {
5979 result = L2CAP_CR_LE_INVALID_SCID;
5980 continue;
5981 }
5982
5983 /* Check if we already have channel with that dcid */
5984 if (__l2cap_get_chan_by_dcid(conn, scid)) {
5985 result = L2CAP_CR_LE_SCID_IN_USE;
5986 continue;
5987 }
5988
5989 chan = pchan->ops->new_connection(pchan);
5990 if (!chan) {
5991 result = L2CAP_CR_LE_NO_MEM;
5992 continue;
5993 }
5994
5995 bacpy(&chan->src, &conn->hcon->src);
5996 bacpy(&chan->dst, &conn->hcon->dst);
5997 chan->src_type = bdaddr_src_type(conn->hcon);
5998 chan->dst_type = bdaddr_dst_type(conn->hcon);
5999 chan->psm = psm;
6000 chan->dcid = scid;
6001 chan->omtu = mtu;
6002 chan->remote_mps = mps;
6003
6004 __l2cap_chan_add(conn, chan);
6005
6006 l2cap_ecred_init(chan, __le16_to_cpu(req->credits));
6007
6008 /* Init response */
6009 if (!pdu.rsp.credits) {
6010 pdu.rsp.mtu = cpu_to_le16(chan->imtu);
6011 pdu.rsp.mps = cpu_to_le16(chan->mps);
6012 pdu.rsp.credits = cpu_to_le16(chan->rx_credits);
6013 }
6014
6015 pdu.dcid[i] = cpu_to_le16(chan->scid);
6016
6017 __set_chan_timer(chan, chan->ops->get_sndtimeo(chan));
6018
6019 chan->ident = cmd->ident;
6020
6021 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) {
6022 l2cap_state_change(chan, BT_CONNECT2);
6023 defer = true;
6024 chan->ops->defer(chan);
6025 } else {
6026 l2cap_chan_ready(chan);
6027 }
6028 }
6029
6030unlock:
6031 l2cap_chan_unlock(pchan);
6032 mutex_unlock(&conn->chan_lock);
6033 l2cap_chan_put(pchan);
6034
6035response:
6036 pdu.rsp.result = cpu_to_le16(result);
6037
6038 if (defer)
6039 return 0;
6040
6041 l2cap_send_cmd(conn, cmd->ident, L2CAP_ECRED_CONN_RSP,
6042 sizeof(pdu.rsp) + len, &pdu);
6043
6044 return 0;
6045}
6046
6047static inline int l2cap_ecred_conn_rsp(struct l2cap_conn *conn,
6048 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
6049 u8 *data)
6050{
6051 struct l2cap_ecred_conn_rsp *rsp = (void *) data;
6052 struct hci_conn *hcon = conn->hcon;
6053 u16 mtu, mps, credits, result;
6054 struct l2cap_chan *chan;
6055 int err = 0, sec_level;
6056 int i = 0;
6057
6058 if (cmd_len < sizeof(*rsp))
6059 return -EPROTO;
6060
6061 mtu = __le16_to_cpu(rsp->mtu);
6062 mps = __le16_to_cpu(rsp->mps);
6063 credits = __le16_to_cpu(rsp->credits);
6064 result = __le16_to_cpu(rsp->result);
6065
6066 BT_DBG("mtu %u mps %u credits %u result 0x%4.4x", mtu, mps, credits,
6067 result);
6068
6069 mutex_lock(&conn->chan_lock);
6070
6071 cmd_len -= sizeof(*rsp);
6072
6073 list_for_each_entry(chan, &conn->chan_l, list) {
6074 u16 dcid;
6075
6076 if (chan->ident != cmd->ident ||
6077 chan->mode != L2CAP_MODE_EXT_FLOWCTL ||
6078 chan->state == BT_CONNECTED)
6079 continue;
6080
6081 l2cap_chan_lock(chan);
6082
6083 /* Check that there is a dcid for each pending channel */
6084 if (cmd_len < sizeof(dcid)) {
6085 l2cap_chan_del(chan, ECONNREFUSED);
6086 l2cap_chan_unlock(chan);
6087 continue;
6088 }
6089
6090 dcid = __le16_to_cpu(rsp->dcid[i++]);
6091 cmd_len -= sizeof(u16);
6092
6093 BT_DBG("dcid[%d] 0x%4.4x", i, dcid);
6094
6095 /* Check if dcid is already in use */
6096 if (dcid && __l2cap_get_chan_by_dcid(conn, dcid)) {
6097 /* If a device receives a
6098 * L2CAP_CREDIT_BASED_CONNECTION_RSP packet with an
6099 * already-assigned Destination CID, then both the
6100 * original channel and the new channel shall be
6101 * immediately discarded and not used.
6102 */
6103 l2cap_chan_del(chan, ECONNREFUSED);
6104 l2cap_chan_unlock(chan);
6105 chan = __l2cap_get_chan_by_dcid(conn, dcid);
6106 l2cap_chan_lock(chan);
6107 l2cap_chan_del(chan, ECONNRESET);
6108 l2cap_chan_unlock(chan);
6109 continue;
6110 }
6111
6112 switch (result) {
6113 case L2CAP_CR_LE_AUTHENTICATION:
6114 case L2CAP_CR_LE_ENCRYPTION:
6115 /* If we already have MITM protection we can't do
6116 * anything.
6117 */
6118 if (hcon->sec_level > BT_SECURITY_MEDIUM) {
6119 l2cap_chan_del(chan, ECONNREFUSED);
6120 break;
6121 }
6122
6123 sec_level = hcon->sec_level + 1;
6124 if (chan->sec_level < sec_level)
6125 chan->sec_level = sec_level;
6126
6127 /* We'll need to send a new Connect Request */
6128 clear_bit(FLAG_ECRED_CONN_REQ_SENT, &chan->flags);
6129
6130 smp_conn_security(hcon, chan->sec_level);
6131 break;
6132
6133 case L2CAP_CR_LE_BAD_PSM:
6134 l2cap_chan_del(chan, ECONNREFUSED);
6135 break;
6136
6137 default:
6138 /* If dcid was not set it means channels was refused */
6139 if (!dcid) {
6140 l2cap_chan_del(chan, ECONNREFUSED);
6141 break;
6142 }
6143
6144 chan->ident = 0;
6145 chan->dcid = dcid;
6146 chan->omtu = mtu;
6147 chan->remote_mps = mps;
6148 chan->tx_credits = credits;
6149 l2cap_chan_ready(chan);
6150 break;
6151 }
6152
6153 l2cap_chan_unlock(chan);
6154 }
6155
6156 mutex_unlock(&conn->chan_lock);
6157
6158 return err;
6159}
6160
6161static inline int l2cap_ecred_reconf_req(struct l2cap_conn *conn,
6162 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
6163 u8 *data)
6164{
6165 struct l2cap_ecred_reconf_req *req = (void *) data;
6166 struct l2cap_ecred_reconf_rsp rsp;
6167 u16 mtu, mps, result;
6168 struct l2cap_chan *chan;
6169 int i, num_scid;
6170
6171 if (!enable_ecred)
6172 return -EINVAL;
6173
6174 if (cmd_len < sizeof(*req) || cmd_len - sizeof(*req) % sizeof(u16)) {
6175 result = L2CAP_CR_LE_INVALID_PARAMS;
6176 goto respond;
6177 }
6178
6179 mtu = __le16_to_cpu(req->mtu);
6180 mps = __le16_to_cpu(req->mps);
6181
6182 BT_DBG("mtu %u mps %u", mtu, mps);
6183
6184 if (mtu < L2CAP_ECRED_MIN_MTU) {
6185 result = L2CAP_RECONF_INVALID_MTU;
6186 goto respond;
6187 }
6188
6189 if (mps < L2CAP_ECRED_MIN_MPS) {
6190 result = L2CAP_RECONF_INVALID_MPS;
6191 goto respond;
6192 }
6193
6194 cmd_len -= sizeof(*req);
6195 num_scid = cmd_len / sizeof(u16);
6196 result = L2CAP_RECONF_SUCCESS;
6197
6198 for (i = 0; i < num_scid; i++) {
6199 u16 scid;
6200
6201 scid = __le16_to_cpu(req->scid[i]);
6202 if (!scid)
6203 return -EPROTO;
6204
6205 chan = __l2cap_get_chan_by_dcid(conn, scid);
6206 if (!chan)
6207 continue;
6208
6209 /* If the MTU value is decreased for any of the included
6210 * channels, then the receiver shall disconnect all
6211 * included channels.
6212 */
6213 if (chan->omtu > mtu) {
6214 BT_ERR("chan %p decreased MTU %u -> %u", chan,
6215 chan->omtu, mtu);
6216 result = L2CAP_RECONF_INVALID_MTU;
6217 }
6218
6219 chan->omtu = mtu;
6220 chan->remote_mps = mps;
6221 }
6222
6223respond:
6224 rsp.result = cpu_to_le16(result);
6225
6226 l2cap_send_cmd(conn, cmd->ident, L2CAP_ECRED_RECONF_RSP, sizeof(rsp),
6227 &rsp);
6228
6229 return 0;
6230}
6231
6232static inline int l2cap_ecred_reconf_rsp(struct l2cap_conn *conn,
6233 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
6234 u8 *data)
6235{
6236 struct l2cap_chan *chan;
6237 struct l2cap_ecred_conn_rsp *rsp = (void *) data;
6238 u16 result;
6239
6240 if (cmd_len < sizeof(*rsp))
6241 return -EPROTO;
6242
6243 result = __le16_to_cpu(rsp->result);
6244
6245 BT_DBG("result 0x%4.4x", rsp->result);
6246
6247 if (!result)
6248 return 0;
6249
6250 list_for_each_entry(chan, &conn->chan_l, list) {
6251 if (chan->ident != cmd->ident)
6252 continue;
6253
6254 l2cap_chan_del(chan, ECONNRESET);
6255 }
6256
6257 return 0;
6258}
6259
6260static inline int l2cap_le_command_rej(struct l2cap_conn *conn,
6261 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
6262 u8 *data)
6263{
6264 struct l2cap_cmd_rej_unk *rej = (struct l2cap_cmd_rej_unk *) data;
6265 struct l2cap_chan *chan;
6266
6267 if (cmd_len < sizeof(*rej))
6268 return -EPROTO;
6269
6270 mutex_lock(&conn->chan_lock);
6271
6272 chan = __l2cap_get_chan_by_ident(conn, cmd->ident);
6273 if (!chan)
6274 goto done;
6275
6276 l2cap_chan_lock(chan);
6277 l2cap_chan_del(chan, ECONNREFUSED);
6278 l2cap_chan_unlock(chan);
6279
6280done:
6281 mutex_unlock(&conn->chan_lock);
6282 return 0;
6283}
6284
6285static inline int l2cap_le_sig_cmd(struct l2cap_conn *conn,
6286 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
6287 u8 *data)
6288{
6289 int err = 0;
6290
6291 switch (cmd->code) {
6292 case L2CAP_COMMAND_REJ:
6293 l2cap_le_command_rej(conn, cmd, cmd_len, data);
6294 break;
6295
6296 case L2CAP_CONN_PARAM_UPDATE_REQ:
6297 err = l2cap_conn_param_update_req(conn, cmd, cmd_len, data);
6298 break;
6299
6300 case L2CAP_CONN_PARAM_UPDATE_RSP:
6301 break;
6302
6303 case L2CAP_LE_CONN_RSP:
6304 l2cap_le_connect_rsp(conn, cmd, cmd_len, data);
6305 break;
6306
6307 case L2CAP_LE_CONN_REQ:
6308 err = l2cap_le_connect_req(conn, cmd, cmd_len, data);
6309 break;
6310
6311 case L2CAP_LE_CREDITS:
6312 err = l2cap_le_credits(conn, cmd, cmd_len, data);
6313 break;
6314
6315 case L2CAP_ECRED_CONN_REQ:
6316 err = l2cap_ecred_conn_req(conn, cmd, cmd_len, data);
6317 break;
6318
6319 case L2CAP_ECRED_CONN_RSP:
6320 err = l2cap_ecred_conn_rsp(conn, cmd, cmd_len, data);
6321 break;
6322
6323 case L2CAP_ECRED_RECONF_REQ:
6324 err = l2cap_ecred_reconf_req(conn, cmd, cmd_len, data);
6325 break;
6326
6327 case L2CAP_ECRED_RECONF_RSP:
6328 err = l2cap_ecred_reconf_rsp(conn, cmd, cmd_len, data);
6329 break;
6330
6331 case L2CAP_DISCONN_REQ:
6332 err = l2cap_disconnect_req(conn, cmd, cmd_len, data);
6333 break;
6334
6335 case L2CAP_DISCONN_RSP:
6336 l2cap_disconnect_rsp(conn, cmd, cmd_len, data);
6337 break;
6338
6339 default:
6340 BT_ERR("Unknown LE signaling command 0x%2.2x", cmd->code);
6341 err = -EINVAL;
6342 break;
6343 }
6344
6345 return err;
6346}
6347
6348static inline void l2cap_le_sig_channel(struct l2cap_conn *conn,
6349 struct sk_buff *skb)
6350{
6351 struct hci_conn *hcon = conn->hcon;
6352 struct l2cap_cmd_hdr *cmd;
6353 u16 len;
6354 int err;
6355
6356 if (hcon->type != LE_LINK)
6357 goto drop;
6358
6359 if (skb->len < L2CAP_CMD_HDR_SIZE)
6360 goto drop;
6361
6362 cmd = (void *) skb->data;
6363 skb_pull(skb, L2CAP_CMD_HDR_SIZE);
6364
6365 len = le16_to_cpu(cmd->len);
6366
6367 BT_DBG("code 0x%2.2x len %d id 0x%2.2x", cmd->code, len, cmd->ident);
6368
6369 if (len != skb->len || !cmd->ident) {
6370 BT_DBG("corrupted command");
6371 goto drop;
6372 }
6373
6374 err = l2cap_le_sig_cmd(conn, cmd, len, skb->data);
6375 if (err) {
6376 struct l2cap_cmd_rej_unk rej;
6377
6378 BT_ERR("Wrong link type (%d)", err);
6379
6380 rej.reason = cpu_to_le16(L2CAP_REJ_NOT_UNDERSTOOD);
6381 l2cap_send_cmd(conn, cmd->ident, L2CAP_COMMAND_REJ,
6382 sizeof(rej), &rej);
6383 }
6384
6385drop:
6386 kfree_skb(skb);
6387}
6388
6389static inline void l2cap_sig_channel(struct l2cap_conn *conn,
6390 struct sk_buff *skb)
6391{
6392 struct hci_conn *hcon = conn->hcon;
6393 struct l2cap_cmd_hdr *cmd;
6394 int err;
6395
6396 l2cap_raw_recv(conn, skb);
6397
6398 if (hcon->type != ACL_LINK)
6399 goto drop;
6400
6401 while (skb->len >= L2CAP_CMD_HDR_SIZE) {
6402 u16 len;
6403
6404 cmd = (void *) skb->data;
6405 skb_pull(skb, L2CAP_CMD_HDR_SIZE);
6406
6407 len = le16_to_cpu(cmd->len);
6408
6409 BT_DBG("code 0x%2.2x len %d id 0x%2.2x", cmd->code, len,
6410 cmd->ident);
6411
6412 if (len > skb->len || !cmd->ident) {
6413 BT_DBG("corrupted command");
6414 break;
6415 }
6416
6417 err = l2cap_bredr_sig_cmd(conn, cmd, len, skb->data);
6418 if (err) {
6419 struct l2cap_cmd_rej_unk rej;
6420
6421 BT_ERR("Wrong link type (%d)", err);
6422
6423 rej.reason = cpu_to_le16(L2CAP_REJ_NOT_UNDERSTOOD);
6424 l2cap_send_cmd(conn, cmd->ident, L2CAP_COMMAND_REJ,
6425 sizeof(rej), &rej);
6426 }
6427
6428 skb_pull(skb, len);
6429 }
6430
6431drop:
6432 kfree_skb(skb);
6433}
6434
6435static int l2cap_check_fcs(struct l2cap_chan *chan, struct sk_buff *skb)
6436{
6437 u16 our_fcs, rcv_fcs;
6438 int hdr_size;
6439
6440 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
6441 hdr_size = L2CAP_EXT_HDR_SIZE;
6442 else
6443 hdr_size = L2CAP_ENH_HDR_SIZE;
6444
6445 if (chan->fcs == L2CAP_FCS_CRC16) {
6446 skb_trim(skb, skb->len - L2CAP_FCS_SIZE);
6447 rcv_fcs = get_unaligned_le16(skb->data + skb->len);
6448 our_fcs = crc16(0, skb->data - hdr_size, skb->len + hdr_size);
6449
6450 if (our_fcs != rcv_fcs)
6451 return -EBADMSG;
6452 }
6453 return 0;
6454}
6455
6456static void l2cap_send_i_or_rr_or_rnr(struct l2cap_chan *chan)
6457{
6458 struct l2cap_ctrl control;
6459
6460 BT_DBG("chan %p", chan);
6461
6462 memset(&control, 0, sizeof(control));
6463 control.sframe = 1;
6464 control.final = 1;
6465 control.reqseq = chan->buffer_seq;
6466 set_bit(CONN_SEND_FBIT, &chan->conn_state);
6467
6468 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
6469 control.super = L2CAP_SUPER_RNR;
6470 l2cap_send_sframe(chan, &control);
6471 }
6472
6473 if (test_and_clear_bit(CONN_REMOTE_BUSY, &chan->conn_state) &&
6474 chan->unacked_frames > 0)
6475 __set_retrans_timer(chan);
6476
6477 /* Send pending iframes */
6478 l2cap_ertm_send(chan);
6479
6480 if (!test_bit(CONN_LOCAL_BUSY, &chan->conn_state) &&
6481 test_bit(CONN_SEND_FBIT, &chan->conn_state)) {
6482 /* F-bit wasn't sent in an s-frame or i-frame yet, so
6483 * send it now.
6484 */
6485 control.super = L2CAP_SUPER_RR;
6486 l2cap_send_sframe(chan, &control);
6487 }
6488}
6489
6490static void append_skb_frag(struct sk_buff *skb, struct sk_buff *new_frag,
6491 struct sk_buff **last_frag)
6492{
6493 /* skb->len reflects data in skb as well as all fragments
6494 * skb->data_len reflects only data in fragments
6495 */
6496 if (!skb_has_frag_list(skb))
6497 skb_shinfo(skb)->frag_list = new_frag;
6498
6499 new_frag->next = NULL;
6500
6501 (*last_frag)->next = new_frag;
6502 *last_frag = new_frag;
6503
6504 skb->len += new_frag->len;
6505 skb->data_len += new_frag->len;
6506 skb->truesize += new_frag->truesize;
6507}
6508
6509static int l2cap_reassemble_sdu(struct l2cap_chan *chan, struct sk_buff *skb,
6510 struct l2cap_ctrl *control)
6511{
6512 int err = -EINVAL;
6513
6514 switch (control->sar) {
6515 case L2CAP_SAR_UNSEGMENTED:
6516 if (chan->sdu)
6517 break;
6518
6519 err = chan->ops->recv(chan, skb);
6520 break;
6521
6522 case L2CAP_SAR_START:
6523 if (chan->sdu)
6524 break;
6525
6526 if (!pskb_may_pull(skb, L2CAP_SDULEN_SIZE))
6527 break;
6528
6529 chan->sdu_len = get_unaligned_le16(skb->data);
6530 skb_pull(skb, L2CAP_SDULEN_SIZE);
6531
6532 if (chan->sdu_len > chan->imtu) {
6533 err = -EMSGSIZE;
6534 break;
6535 }
6536
6537 if (skb->len >= chan->sdu_len)
6538 break;
6539
6540 chan->sdu = skb;
6541 chan->sdu_last_frag = skb;
6542
6543 skb = NULL;
6544 err = 0;
6545 break;
6546
6547 case L2CAP_SAR_CONTINUE:
6548 if (!chan->sdu)
6549 break;
6550
6551 append_skb_frag(chan->sdu, skb,
6552 &chan->sdu_last_frag);
6553 skb = NULL;
6554
6555 if (chan->sdu->len >= chan->sdu_len)
6556 break;
6557
6558 err = 0;
6559 break;
6560
6561 case L2CAP_SAR_END:
6562 if (!chan->sdu)
6563 break;
6564
6565 append_skb_frag(chan->sdu, skb,
6566 &chan->sdu_last_frag);
6567 skb = NULL;
6568
6569 if (chan->sdu->len != chan->sdu_len)
6570 break;
6571
6572 err = chan->ops->recv(chan, chan->sdu);
6573
6574 if (!err) {
6575 /* Reassembly complete */
6576 chan->sdu = NULL;
6577 chan->sdu_last_frag = NULL;
6578 chan->sdu_len = 0;
6579 }
6580 break;
6581 }
6582
6583 if (err) {
6584 kfree_skb(skb);
6585 kfree_skb(chan->sdu);
6586 chan->sdu = NULL;
6587 chan->sdu_last_frag = NULL;
6588 chan->sdu_len = 0;
6589 }
6590
6591 return err;
6592}
6593
6594static int l2cap_resegment(struct l2cap_chan *chan)
6595{
6596 /* Placeholder */
6597 return 0;
6598}
6599
6600void l2cap_chan_busy(struct l2cap_chan *chan, int busy)
6601{
6602 u8 event;
6603
6604 if (chan->mode != L2CAP_MODE_ERTM)
6605 return;
6606
6607 event = busy ? L2CAP_EV_LOCAL_BUSY_DETECTED : L2CAP_EV_LOCAL_BUSY_CLEAR;
6608 l2cap_tx(chan, NULL, NULL, event);
6609}
6610
6611static int l2cap_rx_queued_iframes(struct l2cap_chan *chan)
6612{
6613 int err = 0;
6614 /* Pass sequential frames to l2cap_reassemble_sdu()
6615 * until a gap is encountered.
6616 */
6617
6618 BT_DBG("chan %p", chan);
6619
6620 while (!test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
6621 struct sk_buff *skb;
6622 BT_DBG("Searching for skb with txseq %d (queue len %d)",
6623 chan->buffer_seq, skb_queue_len(&chan->srej_q));
6624
6625 skb = l2cap_ertm_seq_in_queue(&chan->srej_q, chan->buffer_seq);
6626
6627 if (!skb)
6628 break;
6629
6630 skb_unlink(skb, &chan->srej_q);
6631 chan->buffer_seq = __next_seq(chan, chan->buffer_seq);
6632 err = l2cap_reassemble_sdu(chan, skb, &bt_cb(skb)->l2cap);
6633 if (err)
6634 break;
6635 }
6636
6637 if (skb_queue_empty(&chan->srej_q)) {
6638 chan->rx_state = L2CAP_RX_STATE_RECV;
6639 l2cap_send_ack(chan);
6640 }
6641
6642 return err;
6643}
6644
6645static void l2cap_handle_srej(struct l2cap_chan *chan,
6646 struct l2cap_ctrl *control)
6647{
6648 struct sk_buff *skb;
6649
6650 BT_DBG("chan %p, control %p", chan, control);
6651
6652 if (control->reqseq == chan->next_tx_seq) {
6653 BT_DBG("Invalid reqseq %d, disconnecting", control->reqseq);
6654 l2cap_send_disconn_req(chan, ECONNRESET);
6655 return;
6656 }
6657
6658 skb = l2cap_ertm_seq_in_queue(&chan->tx_q, control->reqseq);
6659
6660 if (skb == NULL) {
6661 BT_DBG("Seq %d not available for retransmission",
6662 control->reqseq);
6663 return;
6664 }
6665
6666 if (chan->max_tx != 0 && bt_cb(skb)->l2cap.retries >= chan->max_tx) {
6667 BT_DBG("Retry limit exceeded (%d)", chan->max_tx);
6668 l2cap_send_disconn_req(chan, ECONNRESET);
6669 return;
6670 }
6671
6672 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6673
6674 if (control->poll) {
6675 l2cap_pass_to_tx(chan, control);
6676
6677 set_bit(CONN_SEND_FBIT, &chan->conn_state);
6678 l2cap_retransmit(chan, control);
6679 l2cap_ertm_send(chan);
6680
6681 if (chan->tx_state == L2CAP_TX_STATE_WAIT_F) {
6682 set_bit(CONN_SREJ_ACT, &chan->conn_state);
6683 chan->srej_save_reqseq = control->reqseq;
6684 }
6685 } else {
6686 l2cap_pass_to_tx_fbit(chan, control);
6687
6688 if (control->final) {
6689 if (chan->srej_save_reqseq != control->reqseq ||
6690 !test_and_clear_bit(CONN_SREJ_ACT,
6691 &chan->conn_state))
6692 l2cap_retransmit(chan, control);
6693 } else {
6694 l2cap_retransmit(chan, control);
6695 if (chan->tx_state == L2CAP_TX_STATE_WAIT_F) {
6696 set_bit(CONN_SREJ_ACT, &chan->conn_state);
6697 chan->srej_save_reqseq = control->reqseq;
6698 }
6699 }
6700 }
6701}
6702
6703static void l2cap_handle_rej(struct l2cap_chan *chan,
6704 struct l2cap_ctrl *control)
6705{
6706 struct sk_buff *skb;
6707
6708 BT_DBG("chan %p, control %p", chan, control);
6709
6710 if (control->reqseq == chan->next_tx_seq) {
6711 BT_DBG("Invalid reqseq %d, disconnecting", control->reqseq);
6712 l2cap_send_disconn_req(chan, ECONNRESET);
6713 return;
6714 }
6715
6716 skb = l2cap_ertm_seq_in_queue(&chan->tx_q, control->reqseq);
6717
6718 if (chan->max_tx && skb &&
6719 bt_cb(skb)->l2cap.retries >= chan->max_tx) {
6720 BT_DBG("Retry limit exceeded (%d)", chan->max_tx);
6721 l2cap_send_disconn_req(chan, ECONNRESET);
6722 return;
6723 }
6724
6725 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6726
6727 l2cap_pass_to_tx(chan, control);
6728
6729 if (control->final) {
6730 if (!test_and_clear_bit(CONN_REJ_ACT, &chan->conn_state))
6731 l2cap_retransmit_all(chan, control);
6732 } else {
6733 l2cap_retransmit_all(chan, control);
6734 l2cap_ertm_send(chan);
6735 if (chan->tx_state == L2CAP_TX_STATE_WAIT_F)
6736 set_bit(CONN_REJ_ACT, &chan->conn_state);
6737 }
6738}
6739
6740static u8 l2cap_classify_txseq(struct l2cap_chan *chan, u16 txseq)
6741{
6742 BT_DBG("chan %p, txseq %d", chan, txseq);
6743
6744 BT_DBG("last_acked_seq %d, expected_tx_seq %d", chan->last_acked_seq,
6745 chan->expected_tx_seq);
6746
6747 if (chan->rx_state == L2CAP_RX_STATE_SREJ_SENT) {
6748 if (__seq_offset(chan, txseq, chan->last_acked_seq) >=
6749 chan->tx_win) {
6750 /* See notes below regarding "double poll" and
6751 * invalid packets.
6752 */
6753 if (chan->tx_win <= ((chan->tx_win_max + 1) >> 1)) {
6754 BT_DBG("Invalid/Ignore - after SREJ");
6755 return L2CAP_TXSEQ_INVALID_IGNORE;
6756 } else {
6757 BT_DBG("Invalid - in window after SREJ sent");
6758 return L2CAP_TXSEQ_INVALID;
6759 }
6760 }
6761
6762 if (chan->srej_list.head == txseq) {
6763 BT_DBG("Expected SREJ");
6764 return L2CAP_TXSEQ_EXPECTED_SREJ;
6765 }
6766
6767 if (l2cap_ertm_seq_in_queue(&chan->srej_q, txseq)) {
6768 BT_DBG("Duplicate SREJ - txseq already stored");
6769 return L2CAP_TXSEQ_DUPLICATE_SREJ;
6770 }
6771
6772 if (l2cap_seq_list_contains(&chan->srej_list, txseq)) {
6773 BT_DBG("Unexpected SREJ - not requested");
6774 return L2CAP_TXSEQ_UNEXPECTED_SREJ;
6775 }
6776 }
6777
6778 if (chan->expected_tx_seq == txseq) {
6779 if (__seq_offset(chan, txseq, chan->last_acked_seq) >=
6780 chan->tx_win) {
6781 BT_DBG("Invalid - txseq outside tx window");
6782 return L2CAP_TXSEQ_INVALID;
6783 } else {
6784 BT_DBG("Expected");
6785 return L2CAP_TXSEQ_EXPECTED;
6786 }
6787 }
6788
6789 if (__seq_offset(chan, txseq, chan->last_acked_seq) <
6790 __seq_offset(chan, chan->expected_tx_seq, chan->last_acked_seq)) {
6791 BT_DBG("Duplicate - expected_tx_seq later than txseq");
6792 return L2CAP_TXSEQ_DUPLICATE;
6793 }
6794
6795 if (__seq_offset(chan, txseq, chan->last_acked_seq) >= chan->tx_win) {
6796 /* A source of invalid packets is a "double poll" condition,
6797 * where delays cause us to send multiple poll packets. If
6798 * the remote stack receives and processes both polls,
6799 * sequence numbers can wrap around in such a way that a
6800 * resent frame has a sequence number that looks like new data
6801 * with a sequence gap. This would trigger an erroneous SREJ
6802 * request.
6803 *
6804 * Fortunately, this is impossible with a tx window that's
6805 * less than half of the maximum sequence number, which allows
6806 * invalid frames to be safely ignored.
6807 *
6808 * With tx window sizes greater than half of the tx window
6809 * maximum, the frame is invalid and cannot be ignored. This
6810 * causes a disconnect.
6811 */
6812
6813 if (chan->tx_win <= ((chan->tx_win_max + 1) >> 1)) {
6814 BT_DBG("Invalid/Ignore - txseq outside tx window");
6815 return L2CAP_TXSEQ_INVALID_IGNORE;
6816 } else {
6817 BT_DBG("Invalid - txseq outside tx window");
6818 return L2CAP_TXSEQ_INVALID;
6819 }
6820 } else {
6821 BT_DBG("Unexpected - txseq indicates missing frames");
6822 return L2CAP_TXSEQ_UNEXPECTED;
6823 }
6824}
6825
6826static int l2cap_rx_state_recv(struct l2cap_chan *chan,
6827 struct l2cap_ctrl *control,
6828 struct sk_buff *skb, u8 event)
6829{
6830 int err = 0;
6831 bool skb_in_use = false;
6832
6833 BT_DBG("chan %p, control %p, skb %p, event %d", chan, control, skb,
6834 event);
6835
6836 switch (event) {
6837 case L2CAP_EV_RECV_IFRAME:
6838 switch (l2cap_classify_txseq(chan, control->txseq)) {
6839 case L2CAP_TXSEQ_EXPECTED:
6840 l2cap_pass_to_tx(chan, control);
6841
6842 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
6843 BT_DBG("Busy, discarding expected seq %d",
6844 control->txseq);
6845 break;
6846 }
6847
6848 chan->expected_tx_seq = __next_seq(chan,
6849 control->txseq);
6850
6851 chan->buffer_seq = chan->expected_tx_seq;
6852 skb_in_use = true;
6853
6854 err = l2cap_reassemble_sdu(chan, skb, control);
6855 if (err)
6856 break;
6857
6858 if (control->final) {
6859 if (!test_and_clear_bit(CONN_REJ_ACT,
6860 &chan->conn_state)) {
6861 control->final = 0;
6862 l2cap_retransmit_all(chan, control);
6863 l2cap_ertm_send(chan);
6864 }
6865 }
6866
6867 if (!test_bit(CONN_LOCAL_BUSY, &chan->conn_state))
6868 l2cap_send_ack(chan);
6869 break;
6870 case L2CAP_TXSEQ_UNEXPECTED:
6871 l2cap_pass_to_tx(chan, control);
6872
6873 /* Can't issue SREJ frames in the local busy state.
6874 * Drop this frame, it will be seen as missing
6875 * when local busy is exited.
6876 */
6877 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
6878 BT_DBG("Busy, discarding unexpected seq %d",
6879 control->txseq);
6880 break;
6881 }
6882
6883 /* There was a gap in the sequence, so an SREJ
6884 * must be sent for each missing frame. The
6885 * current frame is stored for later use.
6886 */
6887 skb_queue_tail(&chan->srej_q, skb);
6888 skb_in_use = true;
6889 BT_DBG("Queued %p (queue len %d)", skb,
6890 skb_queue_len(&chan->srej_q));
6891
6892 clear_bit(CONN_SREJ_ACT, &chan->conn_state);
6893 l2cap_seq_list_clear(&chan->srej_list);
6894 l2cap_send_srej(chan, control->txseq);
6895
6896 chan->rx_state = L2CAP_RX_STATE_SREJ_SENT;
6897 break;
6898 case L2CAP_TXSEQ_DUPLICATE:
6899 l2cap_pass_to_tx(chan, control);
6900 break;
6901 case L2CAP_TXSEQ_INVALID_IGNORE:
6902 break;
6903 case L2CAP_TXSEQ_INVALID:
6904 default:
6905 l2cap_send_disconn_req(chan, ECONNRESET);
6906 break;
6907 }
6908 break;
6909 case L2CAP_EV_RECV_RR:
6910 l2cap_pass_to_tx(chan, control);
6911 if (control->final) {
6912 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6913
6914 if (!test_and_clear_bit(CONN_REJ_ACT, &chan->conn_state) &&
6915 !__chan_is_moving(chan)) {
6916 control->final = 0;
6917 l2cap_retransmit_all(chan, control);
6918 }
6919
6920 l2cap_ertm_send(chan);
6921 } else if (control->poll) {
6922 l2cap_send_i_or_rr_or_rnr(chan);
6923 } else {
6924 if (test_and_clear_bit(CONN_REMOTE_BUSY,
6925 &chan->conn_state) &&
6926 chan->unacked_frames)
6927 __set_retrans_timer(chan);
6928
6929 l2cap_ertm_send(chan);
6930 }
6931 break;
6932 case L2CAP_EV_RECV_RNR:
6933 set_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6934 l2cap_pass_to_tx(chan, control);
6935 if (control && control->poll) {
6936 set_bit(CONN_SEND_FBIT, &chan->conn_state);
6937 l2cap_send_rr_or_rnr(chan, 0);
6938 }
6939 __clear_retrans_timer(chan);
6940 l2cap_seq_list_clear(&chan->retrans_list);
6941 break;
6942 case L2CAP_EV_RECV_REJ:
6943 l2cap_handle_rej(chan, control);
6944 break;
6945 case L2CAP_EV_RECV_SREJ:
6946 l2cap_handle_srej(chan, control);
6947 break;
6948 default:
6949 break;
6950 }
6951
6952 if (skb && !skb_in_use) {
6953 BT_DBG("Freeing %p", skb);
6954 kfree_skb(skb);
6955 }
6956
6957 return err;
6958}
6959
6960static int l2cap_rx_state_srej_sent(struct l2cap_chan *chan,
6961 struct l2cap_ctrl *control,
6962 struct sk_buff *skb, u8 event)
6963{
6964 int err = 0;
6965 u16 txseq = control->txseq;
6966 bool skb_in_use = false;
6967
6968 BT_DBG("chan %p, control %p, skb %p, event %d", chan, control, skb,
6969 event);
6970
6971 switch (event) {
6972 case L2CAP_EV_RECV_IFRAME:
6973 switch (l2cap_classify_txseq(chan, txseq)) {
6974 case L2CAP_TXSEQ_EXPECTED:
6975 /* Keep frame for reassembly later */
6976 l2cap_pass_to_tx(chan, control);
6977 skb_queue_tail(&chan->srej_q, skb);
6978 skb_in_use = true;
6979 BT_DBG("Queued %p (queue len %d)", skb,
6980 skb_queue_len(&chan->srej_q));
6981
6982 chan->expected_tx_seq = __next_seq(chan, txseq);
6983 break;
6984 case L2CAP_TXSEQ_EXPECTED_SREJ:
6985 l2cap_seq_list_pop(&chan->srej_list);
6986
6987 l2cap_pass_to_tx(chan, control);
6988 skb_queue_tail(&chan->srej_q, skb);
6989 skb_in_use = true;
6990 BT_DBG("Queued %p (queue len %d)", skb,
6991 skb_queue_len(&chan->srej_q));
6992
6993 err = l2cap_rx_queued_iframes(chan);
6994 if (err)
6995 break;
6996
6997 break;
6998 case L2CAP_TXSEQ_UNEXPECTED:
6999 /* Got a frame that can't be reassembled yet.
7000 * Save it for later, and send SREJs to cover
7001 * the missing frames.
7002 */
7003 skb_queue_tail(&chan->srej_q, skb);
7004 skb_in_use = true;
7005 BT_DBG("Queued %p (queue len %d)", skb,
7006 skb_queue_len(&chan->srej_q));
7007
7008 l2cap_pass_to_tx(chan, control);
7009 l2cap_send_srej(chan, control->txseq);
7010 break;
7011 case L2CAP_TXSEQ_UNEXPECTED_SREJ:
7012 /* This frame was requested with an SREJ, but
7013 * some expected retransmitted frames are
7014 * missing. Request retransmission of missing
7015 * SREJ'd frames.
7016 */
7017 skb_queue_tail(&chan->srej_q, skb);
7018 skb_in_use = true;
7019 BT_DBG("Queued %p (queue len %d)", skb,
7020 skb_queue_len(&chan->srej_q));
7021
7022 l2cap_pass_to_tx(chan, control);
7023 l2cap_send_srej_list(chan, control->txseq);
7024 break;
7025 case L2CAP_TXSEQ_DUPLICATE_SREJ:
7026 /* We've already queued this frame. Drop this copy. */
7027 l2cap_pass_to_tx(chan, control);
7028 break;
7029 case L2CAP_TXSEQ_DUPLICATE:
7030 /* Expecting a later sequence number, so this frame
7031 * was already received. Ignore it completely.
7032 */
7033 break;
7034 case L2CAP_TXSEQ_INVALID_IGNORE:
7035 break;
7036 case L2CAP_TXSEQ_INVALID:
7037 default:
7038 l2cap_send_disconn_req(chan, ECONNRESET);
7039 break;
7040 }
7041 break;
7042 case L2CAP_EV_RECV_RR:
7043 l2cap_pass_to_tx(chan, control);
7044 if (control->final) {
7045 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
7046
7047 if (!test_and_clear_bit(CONN_REJ_ACT,
7048 &chan->conn_state)) {
7049 control->final = 0;
7050 l2cap_retransmit_all(chan, control);
7051 }
7052
7053 l2cap_ertm_send(chan);
7054 } else if (control->poll) {
7055 if (test_and_clear_bit(CONN_REMOTE_BUSY,
7056 &chan->conn_state) &&
7057 chan->unacked_frames) {
7058 __set_retrans_timer(chan);
7059 }
7060
7061 set_bit(CONN_SEND_FBIT, &chan->conn_state);
7062 l2cap_send_srej_tail(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_send_ack(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->poll) {
7076 l2cap_send_srej_tail(chan);
7077 } else {
7078 struct l2cap_ctrl rr_control;
7079 memset(&rr_control, 0, sizeof(rr_control));
7080 rr_control.sframe = 1;
7081 rr_control.super = L2CAP_SUPER_RR;
7082 rr_control.reqseq = chan->buffer_seq;
7083 l2cap_send_sframe(chan, &rr_control);
7084 }
7085
7086 break;
7087 case L2CAP_EV_RECV_REJ:
7088 l2cap_handle_rej(chan, control);
7089 break;
7090 case L2CAP_EV_RECV_SREJ:
7091 l2cap_handle_srej(chan, control);
7092 break;
7093 }
7094
7095 if (skb && !skb_in_use) {
7096 BT_DBG("Freeing %p", skb);
7097 kfree_skb(skb);
7098 }
7099
7100 return err;
7101}
7102
7103static int l2cap_finish_move(struct l2cap_chan *chan)
7104{
7105 BT_DBG("chan %p", chan);
7106
7107 chan->rx_state = L2CAP_RX_STATE_RECV;
7108
7109 if (chan->hs_hcon)
7110 chan->conn->mtu = chan->hs_hcon->hdev->block_mtu;
7111 else
7112 chan->conn->mtu = chan->conn->hcon->hdev->acl_mtu;
7113
7114 return l2cap_resegment(chan);
7115}
7116
7117static int l2cap_rx_state_wait_p(struct l2cap_chan *chan,
7118 struct l2cap_ctrl *control,
7119 struct sk_buff *skb, u8 event)
7120{
7121 int err;
7122
7123 BT_DBG("chan %p, control %p, skb %p, event %d", chan, control, skb,
7124 event);
7125
7126 if (!control->poll)
7127 return -EPROTO;
7128
7129 l2cap_process_reqseq(chan, control->reqseq);
7130
7131 if (!skb_queue_empty(&chan->tx_q))
7132 chan->tx_send_head = skb_peek(&chan->tx_q);
7133 else
7134 chan->tx_send_head = NULL;
7135
7136 /* Rewind next_tx_seq to the point expected
7137 * by the receiver.
7138 */
7139 chan->next_tx_seq = control->reqseq;
7140 chan->unacked_frames = 0;
7141
7142 err = l2cap_finish_move(chan);
7143 if (err)
7144 return err;
7145
7146 set_bit(CONN_SEND_FBIT, &chan->conn_state);
7147 l2cap_send_i_or_rr_or_rnr(chan);
7148
7149 if (event == L2CAP_EV_RECV_IFRAME)
7150 return -EPROTO;
7151
7152 return l2cap_rx_state_recv(chan, control, NULL, event);
7153}
7154
7155static int l2cap_rx_state_wait_f(struct l2cap_chan *chan,
7156 struct l2cap_ctrl *control,
7157 struct sk_buff *skb, u8 event)
7158{
7159 int err;
7160
7161 if (!control->final)
7162 return -EPROTO;
7163
7164 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
7165
7166 chan->rx_state = L2CAP_RX_STATE_RECV;
7167 l2cap_process_reqseq(chan, control->reqseq);
7168
7169 if (!skb_queue_empty(&chan->tx_q))
7170 chan->tx_send_head = skb_peek(&chan->tx_q);
7171 else
7172 chan->tx_send_head = NULL;
7173
7174 /* Rewind next_tx_seq to the point expected
7175 * by the receiver.
7176 */
7177 chan->next_tx_seq = control->reqseq;
7178 chan->unacked_frames = 0;
7179
7180 if (chan->hs_hcon)
7181 chan->conn->mtu = chan->hs_hcon->hdev->block_mtu;
7182 else
7183 chan->conn->mtu = chan->conn->hcon->hdev->acl_mtu;
7184
7185 err = l2cap_resegment(chan);
7186
7187 if (!err)
7188 err = l2cap_rx_state_recv(chan, control, skb, event);
7189
7190 return err;
7191}
7192
7193static bool __valid_reqseq(struct l2cap_chan *chan, u16 reqseq)
7194{
7195 /* Make sure reqseq is for a packet that has been sent but not acked */
7196 u16 unacked;
7197
7198 unacked = __seq_offset(chan, chan->next_tx_seq, chan->expected_ack_seq);
7199 return __seq_offset(chan, chan->next_tx_seq, reqseq) <= unacked;
7200}
7201
7202static int l2cap_rx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
7203 struct sk_buff *skb, u8 event)
7204{
7205 int err = 0;
7206
7207 BT_DBG("chan %p, control %p, skb %p, event %d, state %d", chan,
7208 control, skb, event, chan->rx_state);
7209
7210 if (__valid_reqseq(chan, control->reqseq)) {
7211 switch (chan->rx_state) {
7212 case L2CAP_RX_STATE_RECV:
7213 err = l2cap_rx_state_recv(chan, control, skb, event);
7214 break;
7215 case L2CAP_RX_STATE_SREJ_SENT:
7216 err = l2cap_rx_state_srej_sent(chan, control, skb,
7217 event);
7218 break;
7219 case L2CAP_RX_STATE_WAIT_P:
7220 err = l2cap_rx_state_wait_p(chan, control, skb, event);
7221 break;
7222 case L2CAP_RX_STATE_WAIT_F:
7223 err = l2cap_rx_state_wait_f(chan, control, skb, event);
7224 break;
7225 default:
7226 /* shut it down */
7227 break;
7228 }
7229 } else {
7230 BT_DBG("Invalid reqseq %d (next_tx_seq %d, expected_ack_seq %d",
7231 control->reqseq, chan->next_tx_seq,
7232 chan->expected_ack_seq);
7233 l2cap_send_disconn_req(chan, ECONNRESET);
7234 }
7235
7236 return err;
7237}
7238
7239static int l2cap_stream_rx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
7240 struct sk_buff *skb)
7241{
7242 BT_DBG("chan %p, control %p, skb %p, state %d", chan, control, skb,
7243 chan->rx_state);
7244
7245 if (l2cap_classify_txseq(chan, control->txseq) ==
7246 L2CAP_TXSEQ_EXPECTED) {
7247 l2cap_pass_to_tx(chan, control);
7248
7249 BT_DBG("buffer_seq %d->%d", chan->buffer_seq,
7250 __next_seq(chan, chan->buffer_seq));
7251
7252 chan->buffer_seq = __next_seq(chan, chan->buffer_seq);
7253
7254 l2cap_reassemble_sdu(chan, skb, control);
7255 } else {
7256 if (chan->sdu) {
7257 kfree_skb(chan->sdu);
7258 chan->sdu = NULL;
7259 }
7260 chan->sdu_last_frag = NULL;
7261 chan->sdu_len = 0;
7262
7263 if (skb) {
7264 BT_DBG("Freeing %p", skb);
7265 kfree_skb(skb);
7266 }
7267 }
7268
7269 chan->last_acked_seq = control->txseq;
7270 chan->expected_tx_seq = __next_seq(chan, control->txseq);
7271
7272 return 0;
7273}
7274
7275static int l2cap_data_rcv(struct l2cap_chan *chan, struct sk_buff *skb)
7276{
7277 struct l2cap_ctrl *control = &bt_cb(skb)->l2cap;
7278 u16 len;
7279 u8 event;
7280
7281 __unpack_control(chan, skb);
7282
7283 len = skb->len;
7284
7285 /*
7286 * We can just drop the corrupted I-frame here.
7287 * Receiver will miss it and start proper recovery
7288 * procedures and ask for retransmission.
7289 */
7290 if (l2cap_check_fcs(chan, skb))
7291 goto drop;
7292
7293 if (!control->sframe && control->sar == L2CAP_SAR_START)
7294 len -= L2CAP_SDULEN_SIZE;
7295
7296 if (chan->fcs == L2CAP_FCS_CRC16)
7297 len -= L2CAP_FCS_SIZE;
7298
7299 if (len > chan->mps) {
7300 l2cap_send_disconn_req(chan, ECONNRESET);
7301 goto drop;
7302 }
7303
7304 if ((chan->mode == L2CAP_MODE_ERTM ||
7305 chan->mode == L2CAP_MODE_STREAMING) && sk_filter(chan->data, skb))
7306 goto drop;
7307
7308 if (!control->sframe) {
7309 int err;
7310
7311 BT_DBG("iframe sar %d, reqseq %d, final %d, txseq %d",
7312 control->sar, control->reqseq, control->final,
7313 control->txseq);
7314
7315 /* Validate F-bit - F=0 always valid, F=1 only
7316 * valid in TX WAIT_F
7317 */
7318 if (control->final && chan->tx_state != L2CAP_TX_STATE_WAIT_F)
7319 goto drop;
7320
7321 if (chan->mode != L2CAP_MODE_STREAMING) {
7322 event = L2CAP_EV_RECV_IFRAME;
7323 err = l2cap_rx(chan, control, skb, event);
7324 } else {
7325 err = l2cap_stream_rx(chan, control, skb);
7326 }
7327
7328 if (err)
7329 l2cap_send_disconn_req(chan, ECONNRESET);
7330 } else {
7331 const u8 rx_func_to_event[4] = {
7332 L2CAP_EV_RECV_RR, L2CAP_EV_RECV_REJ,
7333 L2CAP_EV_RECV_RNR, L2CAP_EV_RECV_SREJ
7334 };
7335
7336 /* Only I-frames are expected in streaming mode */
7337 if (chan->mode == L2CAP_MODE_STREAMING)
7338 goto drop;
7339
7340 BT_DBG("sframe reqseq %d, final %d, poll %d, super %d",
7341 control->reqseq, control->final, control->poll,
7342 control->super);
7343
7344 if (len != 0) {
7345 BT_ERR("Trailing bytes: %d in sframe", len);
7346 l2cap_send_disconn_req(chan, ECONNRESET);
7347 goto drop;
7348 }
7349
7350 /* Validate F and P bits */
7351 if (control->final && (control->poll ||
7352 chan->tx_state != L2CAP_TX_STATE_WAIT_F))
7353 goto drop;
7354
7355 event = rx_func_to_event[control->super];
7356 if (l2cap_rx(chan, control, skb, event))
7357 l2cap_send_disconn_req(chan, ECONNRESET);
7358 }
7359
7360 return 0;
7361
7362drop:
7363 kfree_skb(skb);
7364 return 0;
7365}
7366
7367static void l2cap_chan_le_send_credits(struct l2cap_chan *chan)
7368{
7369 struct l2cap_conn *conn = chan->conn;
7370 struct l2cap_le_credits pkt;
7371 u16 return_credits;
7372
7373 return_credits = (chan->imtu / chan->mps) + 1;
7374
7375 if (chan->rx_credits >= return_credits)
7376 return;
7377
7378 return_credits -= chan->rx_credits;
7379
7380 BT_DBG("chan %p returning %u credits to sender", chan, return_credits);
7381
7382 chan->rx_credits += return_credits;
7383
7384 pkt.cid = cpu_to_le16(chan->scid);
7385 pkt.credits = cpu_to_le16(return_credits);
7386
7387 chan->ident = l2cap_get_ident(conn);
7388
7389 l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CREDITS, sizeof(pkt), &pkt);
7390}
7391
7392static int l2cap_ecred_recv(struct l2cap_chan *chan, struct sk_buff *skb)
7393{
7394 int err;
7395
7396 BT_DBG("SDU reassemble complete: chan %p skb->len %u", chan, skb->len);
7397
7398 /* Wait recv to confirm reception before updating the credits */
7399 err = chan->ops->recv(chan, skb);
7400
7401 /* Update credits whenever an SDU is received */
7402 l2cap_chan_le_send_credits(chan);
7403
7404 return err;
7405}
7406
7407static int l2cap_ecred_data_rcv(struct l2cap_chan *chan, struct sk_buff *skb)
7408{
7409 int err;
7410
7411 if (!chan->rx_credits) {
7412 BT_ERR("No credits to receive LE L2CAP data");
7413 l2cap_send_disconn_req(chan, ECONNRESET);
7414 return -ENOBUFS;
7415 }
7416
7417 if (chan->imtu < skb->len) {
7418 BT_ERR("Too big LE L2CAP PDU");
7419 return -ENOBUFS;
7420 }
7421
7422 chan->rx_credits--;
7423 BT_DBG("rx_credits %u -> %u", chan->rx_credits + 1, chan->rx_credits);
7424
7425 /* Update if remote had run out of credits, this should only happens
7426 * if the remote is not using the entire MPS.
7427 */
7428 if (!chan->rx_credits)
7429 l2cap_chan_le_send_credits(chan);
7430
7431 err = 0;
7432
7433 if (!chan->sdu) {
7434 u16 sdu_len;
7435
7436 sdu_len = get_unaligned_le16(skb->data);
7437 skb_pull(skb, L2CAP_SDULEN_SIZE);
7438
7439 BT_DBG("Start of new SDU. sdu_len %u skb->len %u imtu %u",
7440 sdu_len, skb->len, chan->imtu);
7441
7442 if (sdu_len > chan->imtu) {
7443 BT_ERR("Too big LE L2CAP SDU length received");
7444 err = -EMSGSIZE;
7445 goto failed;
7446 }
7447
7448 if (skb->len > sdu_len) {
7449 BT_ERR("Too much LE L2CAP data received");
7450 err = -EINVAL;
7451 goto failed;
7452 }
7453
7454 if (skb->len == sdu_len)
7455 return l2cap_ecred_recv(chan, skb);
7456
7457 chan->sdu = skb;
7458 chan->sdu_len = sdu_len;
7459 chan->sdu_last_frag = skb;
7460
7461 /* Detect if remote is not able to use the selected MPS */
7462 if (skb->len + L2CAP_SDULEN_SIZE < chan->mps) {
7463 u16 mps_len = skb->len + L2CAP_SDULEN_SIZE;
7464
7465 /* Adjust the number of credits */
7466 BT_DBG("chan->mps %u -> %u", chan->mps, mps_len);
7467 chan->mps = mps_len;
7468 l2cap_chan_le_send_credits(chan);
7469 }
7470
7471 return 0;
7472 }
7473
7474 BT_DBG("SDU fragment. chan->sdu->len %u skb->len %u chan->sdu_len %u",
7475 chan->sdu->len, skb->len, chan->sdu_len);
7476
7477 if (chan->sdu->len + skb->len > chan->sdu_len) {
7478 BT_ERR("Too much LE L2CAP data received");
7479 err = -EINVAL;
7480 goto failed;
7481 }
7482
7483 append_skb_frag(chan->sdu, skb, &chan->sdu_last_frag);
7484 skb = NULL;
7485
7486 if (chan->sdu->len == chan->sdu_len) {
7487 err = l2cap_ecred_recv(chan, chan->sdu);
7488 if (!err) {
7489 chan->sdu = NULL;
7490 chan->sdu_last_frag = NULL;
7491 chan->sdu_len = 0;
7492 }
7493 }
7494
7495failed:
7496 if (err) {
7497 kfree_skb(skb);
7498 kfree_skb(chan->sdu);
7499 chan->sdu = NULL;
7500 chan->sdu_last_frag = NULL;
7501 chan->sdu_len = 0;
7502 }
7503
7504 /* We can't return an error here since we took care of the skb
7505 * freeing internally. An error return would cause the caller to
7506 * do a double-free of the skb.
7507 */
7508 return 0;
7509}
7510
7511static void l2cap_data_channel(struct l2cap_conn *conn, u16 cid,
7512 struct sk_buff *skb)
7513{
7514 struct l2cap_chan *chan;
7515
7516 chan = l2cap_get_chan_by_scid(conn, cid);
7517 if (!chan) {
7518 if (cid == L2CAP_CID_A2MP) {
7519 chan = a2mp_channel_create(conn, skb);
7520 if (!chan) {
7521 kfree_skb(skb);
7522 return;
7523 }
7524
7525 l2cap_chan_lock(chan);
7526 } else {
7527 BT_DBG("unknown cid 0x%4.4x", cid);
7528 /* Drop packet and return */
7529 kfree_skb(skb);
7530 return;
7531 }
7532 }
7533
7534 BT_DBG("chan %p, len %d", chan, skb->len);
7535
7536 /* If we receive data on a fixed channel before the info req/rsp
7537 * procdure is done simply assume that the channel is supported
7538 * and mark it as ready.
7539 */
7540 if (chan->chan_type == L2CAP_CHAN_FIXED)
7541 l2cap_chan_ready(chan);
7542
7543 if (chan->state != BT_CONNECTED)
7544 goto drop;
7545
7546 switch (chan->mode) {
7547 case L2CAP_MODE_LE_FLOWCTL:
7548 case L2CAP_MODE_EXT_FLOWCTL:
7549 if (l2cap_ecred_data_rcv(chan, skb) < 0)
7550 goto drop;
7551
7552 goto done;
7553
7554 case L2CAP_MODE_BASIC:
7555 /* If socket recv buffers overflows we drop data here
7556 * which is *bad* because L2CAP has to be reliable.
7557 * But we don't have any other choice. L2CAP doesn't
7558 * provide flow control mechanism. */
7559
7560 if (chan->imtu < skb->len) {
7561 BT_ERR("Dropping L2CAP data: receive buffer overflow");
7562 goto drop;
7563 }
7564
7565 if (!chan->ops->recv(chan, skb))
7566 goto done;
7567 break;
7568
7569 case L2CAP_MODE_ERTM:
7570 case L2CAP_MODE_STREAMING:
7571 l2cap_data_rcv(chan, skb);
7572 goto done;
7573
7574 default:
7575 BT_DBG("chan %p: bad mode 0x%2.2x", chan, chan->mode);
7576 break;
7577 }
7578
7579drop:
7580 kfree_skb(skb);
7581
7582done:
7583 l2cap_chan_unlock(chan);
7584}
7585
7586static void l2cap_conless_channel(struct l2cap_conn *conn, __le16 psm,
7587 struct sk_buff *skb)
7588{
7589 struct hci_conn *hcon = conn->hcon;
7590 struct l2cap_chan *chan;
7591
7592 if (hcon->type != ACL_LINK)
7593 goto free_skb;
7594
7595 chan = l2cap_global_chan_by_psm(0, psm, &hcon->src, &hcon->dst,
7596 ACL_LINK);
7597 if (!chan)
7598 goto free_skb;
7599
7600 BT_DBG("chan %p, len %d", chan, skb->len);
7601
7602 if (chan->state != BT_BOUND && chan->state != BT_CONNECTED)
7603 goto drop;
7604
7605 if (chan->imtu < skb->len)
7606 goto drop;
7607
7608 /* Store remote BD_ADDR and PSM for msg_name */
7609 bacpy(&bt_cb(skb)->l2cap.bdaddr, &hcon->dst);
7610 bt_cb(skb)->l2cap.psm = psm;
7611
7612 if (!chan->ops->recv(chan, skb)) {
7613 l2cap_chan_put(chan);
7614 return;
7615 }
7616
7617drop:
7618 l2cap_chan_put(chan);
7619free_skb:
7620 kfree_skb(skb);
7621}
7622
7623static void l2cap_recv_frame(struct l2cap_conn *conn, struct sk_buff *skb)
7624{
7625 struct l2cap_hdr *lh = (void *) skb->data;
7626 struct hci_conn *hcon = conn->hcon;
7627 u16 cid, len;
7628 __le16 psm;
7629
7630 if (hcon->state != BT_CONNECTED) {
7631 BT_DBG("queueing pending rx skb");
7632 skb_queue_tail(&conn->pending_rx, skb);
7633 return;
7634 }
7635
7636 skb_pull(skb, L2CAP_HDR_SIZE);
7637 cid = __le16_to_cpu(lh->cid);
7638 len = __le16_to_cpu(lh->len);
7639
7640 if (len != skb->len) {
7641 kfree_skb(skb);
7642 return;
7643 }
7644
7645 /* Since we can't actively block incoming LE connections we must
7646 * at least ensure that we ignore incoming data from them.
7647 */
7648 if (hcon->type == LE_LINK &&
7649 hci_bdaddr_list_lookup(&hcon->hdev->blacklist, &hcon->dst,
7650 bdaddr_dst_type(hcon))) {
7651 kfree_skb(skb);
7652 return;
7653 }
7654
7655 BT_DBG("len %d, cid 0x%4.4x", len, cid);
7656
7657 switch (cid) {
7658 case L2CAP_CID_SIGNALING:
7659 l2cap_sig_channel(conn, skb);
7660 break;
7661
7662 case L2CAP_CID_CONN_LESS:
7663 psm = get_unaligned((__le16 *) skb->data);
7664 skb_pull(skb, L2CAP_PSMLEN_SIZE);
7665 l2cap_conless_channel(conn, psm, skb);
7666 break;
7667
7668 case L2CAP_CID_LE_SIGNALING:
7669 l2cap_le_sig_channel(conn, skb);
7670 break;
7671
7672 default:
7673 l2cap_data_channel(conn, cid, skb);
7674 break;
7675 }
7676}
7677
7678static void process_pending_rx(struct work_struct *work)
7679{
7680 struct l2cap_conn *conn = container_of(work, struct l2cap_conn,
7681 pending_rx_work);
7682 struct sk_buff *skb;
7683
7684 BT_DBG("");
7685
7686 while ((skb = skb_dequeue(&conn->pending_rx)))
7687 l2cap_recv_frame(conn, skb);
7688}
7689
7690static struct l2cap_conn *l2cap_conn_add(struct hci_conn *hcon)
7691{
7692 struct l2cap_conn *conn = hcon->l2cap_data;
7693 struct hci_chan *hchan;
7694
7695 if (conn)
7696 return conn;
7697
7698 hchan = hci_chan_create(hcon);
7699 if (!hchan)
7700 return NULL;
7701
7702 conn = kzalloc(sizeof(*conn), GFP_KERNEL);
7703 if (!conn) {
7704 hci_chan_del(hchan);
7705 return NULL;
7706 }
7707
7708 kref_init(&conn->ref);
7709 hcon->l2cap_data = conn;
7710 conn->hcon = hci_conn_get(hcon);
7711 conn->hchan = hchan;
7712
7713 BT_DBG("hcon %p conn %p hchan %p", hcon, conn, hchan);
7714
7715 switch (hcon->type) {
7716 case LE_LINK:
7717 if (hcon->hdev->le_mtu) {
7718 conn->mtu = hcon->hdev->le_mtu;
7719 break;
7720 }
7721 fallthrough;
7722 default:
7723 conn->mtu = hcon->hdev->acl_mtu;
7724 break;
7725 }
7726
7727 conn->feat_mask = 0;
7728
7729 conn->local_fixed_chan = L2CAP_FC_SIG_BREDR | L2CAP_FC_CONNLESS;
7730
7731 if (hcon->type == ACL_LINK &&
7732 hci_dev_test_flag(hcon->hdev, HCI_HS_ENABLED))
7733 conn->local_fixed_chan |= L2CAP_FC_A2MP;
7734
7735 if (hci_dev_test_flag(hcon->hdev, HCI_LE_ENABLED) &&
7736 (bredr_sc_enabled(hcon->hdev) ||
7737 hci_dev_test_flag(hcon->hdev, HCI_FORCE_BREDR_SMP)))
7738 conn->local_fixed_chan |= L2CAP_FC_SMP_BREDR;
7739
7740 mutex_init(&conn->ident_lock);
7741 mutex_init(&conn->chan_lock);
7742
7743 INIT_LIST_HEAD(&conn->chan_l);
7744 INIT_LIST_HEAD(&conn->users);
7745
7746 INIT_DELAYED_WORK(&conn->info_timer, l2cap_info_timeout);
7747
7748 skb_queue_head_init(&conn->pending_rx);
7749 INIT_WORK(&conn->pending_rx_work, process_pending_rx);
7750 INIT_WORK(&conn->id_addr_update_work, l2cap_conn_update_id_addr);
7751
7752 conn->disc_reason = HCI_ERROR_REMOTE_USER_TERM;
7753
7754 return conn;
7755}
7756
7757static bool is_valid_psm(u16 psm, u8 dst_type) {
7758 if (!psm)
7759 return false;
7760
7761 if (bdaddr_type_is_le(dst_type))
7762 return (psm <= 0x00ff);
7763
7764 /* PSM must be odd and lsb of upper byte must be 0 */
7765 return ((psm & 0x0101) == 0x0001);
7766}
7767
7768struct l2cap_chan_data {
7769 struct l2cap_chan *chan;
7770 struct pid *pid;
7771 int count;
7772};
7773
7774static void l2cap_chan_by_pid(struct l2cap_chan *chan, void *data)
7775{
7776 struct l2cap_chan_data *d = data;
7777 struct pid *pid;
7778
7779 if (chan == d->chan)
7780 return;
7781
7782 if (!test_bit(FLAG_DEFER_SETUP, &chan->flags))
7783 return;
7784
7785 pid = chan->ops->get_peer_pid(chan);
7786
7787 /* Only count deferred channels with the same PID/PSM */
7788 if (d->pid != pid || chan->psm != d->chan->psm || chan->ident ||
7789 chan->mode != L2CAP_MODE_EXT_FLOWCTL || chan->state != BT_CONNECT)
7790 return;
7791
7792 d->count++;
7793}
7794
7795int l2cap_chan_connect(struct l2cap_chan *chan, __le16 psm, u16 cid,
7796 bdaddr_t *dst, u8 dst_type)
7797{
7798 struct l2cap_conn *conn;
7799 struct hci_conn *hcon;
7800 struct hci_dev *hdev;
7801 int err;
7802
7803 BT_DBG("%pMR -> %pMR (type %u) psm 0x%4.4x mode 0x%2.2x", &chan->src,
7804 dst, dst_type, __le16_to_cpu(psm), chan->mode);
7805
7806 hdev = hci_get_route(dst, &chan->src, chan->src_type);
7807 if (!hdev)
7808 return -EHOSTUNREACH;
7809
7810 hci_dev_lock(hdev);
7811
7812 if (!is_valid_psm(__le16_to_cpu(psm), dst_type) && !cid &&
7813 chan->chan_type != L2CAP_CHAN_RAW) {
7814 err = -EINVAL;
7815 goto done;
7816 }
7817
7818 if (chan->chan_type == L2CAP_CHAN_CONN_ORIENTED && !psm) {
7819 err = -EINVAL;
7820 goto done;
7821 }
7822
7823 if (chan->chan_type == L2CAP_CHAN_FIXED && !cid) {
7824 err = -EINVAL;
7825 goto done;
7826 }
7827
7828 switch (chan->mode) {
7829 case L2CAP_MODE_BASIC:
7830 break;
7831 case L2CAP_MODE_LE_FLOWCTL:
7832 break;
7833 case L2CAP_MODE_EXT_FLOWCTL:
7834 if (!enable_ecred) {
7835 err = -EOPNOTSUPP;
7836 goto done;
7837 }
7838 break;
7839 case L2CAP_MODE_ERTM:
7840 case L2CAP_MODE_STREAMING:
7841 if (!disable_ertm)
7842 break;
7843 fallthrough;
7844 default:
7845 err = -EOPNOTSUPP;
7846 goto done;
7847 }
7848
7849 switch (chan->state) {
7850 case BT_CONNECT:
7851 case BT_CONNECT2:
7852 case BT_CONFIG:
7853 /* Already connecting */
7854 err = 0;
7855 goto done;
7856
7857 case BT_CONNECTED:
7858 /* Already connected */
7859 err = -EISCONN;
7860 goto done;
7861
7862 case BT_OPEN:
7863 case BT_BOUND:
7864 /* Can connect */
7865 break;
7866
7867 default:
7868 err = -EBADFD;
7869 goto done;
7870 }
7871
7872 /* Set destination address and psm */
7873 bacpy(&chan->dst, dst);
7874 chan->dst_type = dst_type;
7875
7876 chan->psm = psm;
7877 chan->dcid = cid;
7878
7879 if (bdaddr_type_is_le(dst_type)) {
7880 /* Convert from L2CAP channel address type to HCI address type
7881 */
7882 if (dst_type == BDADDR_LE_PUBLIC)
7883 dst_type = ADDR_LE_DEV_PUBLIC;
7884 else
7885 dst_type = ADDR_LE_DEV_RANDOM;
7886
7887 if (hci_dev_test_flag(hdev, HCI_ADVERTISING))
7888 hcon = hci_connect_le(hdev, dst, dst_type,
7889 chan->sec_level,
7890 HCI_LE_CONN_TIMEOUT,
7891 HCI_ROLE_SLAVE, NULL);
7892 else
7893 hcon = hci_connect_le_scan(hdev, dst, dst_type,
7894 chan->sec_level,
7895 HCI_LE_CONN_TIMEOUT,
7896 CONN_REASON_L2CAP_CHAN);
7897
7898 } else {
7899 u8 auth_type = l2cap_get_auth_type(chan);
7900 hcon = hci_connect_acl(hdev, dst, chan->sec_level, auth_type,
7901 CONN_REASON_L2CAP_CHAN);
7902 }
7903
7904 if (IS_ERR(hcon)) {
7905 err = PTR_ERR(hcon);
7906 goto done;
7907 }
7908
7909 conn = l2cap_conn_add(hcon);
7910 if (!conn) {
7911 hci_conn_drop(hcon);
7912 err = -ENOMEM;
7913 goto done;
7914 }
7915
7916 if (chan->mode == L2CAP_MODE_EXT_FLOWCTL) {
7917 struct l2cap_chan_data data;
7918
7919 data.chan = chan;
7920 data.pid = chan->ops->get_peer_pid(chan);
7921 data.count = 1;
7922
7923 l2cap_chan_list(conn, l2cap_chan_by_pid, &data);
7924
7925 /* Check if there isn't too many channels being connected */
7926 if (data.count > L2CAP_ECRED_CONN_SCID_MAX) {
7927 hci_conn_drop(hcon);
7928 err = -EPROTO;
7929 goto done;
7930 }
7931 }
7932
7933 mutex_lock(&conn->chan_lock);
7934 l2cap_chan_lock(chan);
7935
7936 if (cid && __l2cap_get_chan_by_dcid(conn, cid)) {
7937 hci_conn_drop(hcon);
7938 err = -EBUSY;
7939 goto chan_unlock;
7940 }
7941
7942 /* Update source addr of the socket */
7943 bacpy(&chan->src, &hcon->src);
7944 chan->src_type = bdaddr_src_type(hcon);
7945
7946 __l2cap_chan_add(conn, chan);
7947
7948 /* l2cap_chan_add takes its own ref so we can drop this one */
7949 hci_conn_drop(hcon);
7950
7951 l2cap_state_change(chan, BT_CONNECT);
7952 __set_chan_timer(chan, chan->ops->get_sndtimeo(chan));
7953
7954 /* Release chan->sport so that it can be reused by other
7955 * sockets (as it's only used for listening sockets).
7956 */
7957 write_lock(&chan_list_lock);
7958 chan->sport = 0;
7959 write_unlock(&chan_list_lock);
7960
7961 if (hcon->state == BT_CONNECTED) {
7962 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) {
7963 __clear_chan_timer(chan);
7964 if (l2cap_chan_check_security(chan, true))
7965 l2cap_state_change(chan, BT_CONNECTED);
7966 } else
7967 l2cap_do_start(chan);
7968 }
7969
7970 err = 0;
7971
7972chan_unlock:
7973 l2cap_chan_unlock(chan);
7974 mutex_unlock(&conn->chan_lock);
7975done:
7976 hci_dev_unlock(hdev);
7977 hci_dev_put(hdev);
7978 return err;
7979}
7980EXPORT_SYMBOL_GPL(l2cap_chan_connect);
7981
7982static void l2cap_ecred_reconfigure(struct l2cap_chan *chan)
7983{
7984 struct l2cap_conn *conn = chan->conn;
7985 struct {
7986 struct l2cap_ecred_reconf_req req;
7987 __le16 scid;
7988 } pdu;
7989
7990 pdu.req.mtu = cpu_to_le16(chan->imtu);
7991 pdu.req.mps = cpu_to_le16(chan->mps);
7992 pdu.scid = cpu_to_le16(chan->scid);
7993
7994 chan->ident = l2cap_get_ident(conn);
7995
7996 l2cap_send_cmd(conn, chan->ident, L2CAP_ECRED_RECONF_REQ,
7997 sizeof(pdu), &pdu);
7998}
7999
8000int l2cap_chan_reconfigure(struct l2cap_chan *chan, __u16 mtu)
8001{
8002 if (chan->imtu > mtu)
8003 return -EINVAL;
8004
8005 BT_DBG("chan %p mtu 0x%4.4x", chan, mtu);
8006
8007 chan->imtu = mtu;
8008
8009 l2cap_ecred_reconfigure(chan);
8010
8011 return 0;
8012}
8013
8014/* ---- L2CAP interface with lower layer (HCI) ---- */
8015
8016int l2cap_connect_ind(struct hci_dev *hdev, bdaddr_t *bdaddr)
8017{
8018 int exact = 0, lm1 = 0, lm2 = 0;
8019 struct l2cap_chan *c;
8020
8021 BT_DBG("hdev %s, bdaddr %pMR", hdev->name, bdaddr);
8022
8023 /* Find listening sockets and check their link_mode */
8024 read_lock(&chan_list_lock);
8025 list_for_each_entry(c, &chan_list, global_l) {
8026 if (c->state != BT_LISTEN)
8027 continue;
8028
8029 if (!bacmp(&c->src, &hdev->bdaddr)) {
8030 lm1 |= HCI_LM_ACCEPT;
8031 if (test_bit(FLAG_ROLE_SWITCH, &c->flags))
8032 lm1 |= HCI_LM_MASTER;
8033 exact++;
8034 } else if (!bacmp(&c->src, BDADDR_ANY)) {
8035 lm2 |= HCI_LM_ACCEPT;
8036 if (test_bit(FLAG_ROLE_SWITCH, &c->flags))
8037 lm2 |= HCI_LM_MASTER;
8038 }
8039 }
8040 read_unlock(&chan_list_lock);
8041
8042 return exact ? lm1 : lm2;
8043}
8044
8045/* Find the next fixed channel in BT_LISTEN state, continue iteration
8046 * from an existing channel in the list or from the beginning of the
8047 * global list (by passing NULL as first parameter).
8048 */
8049static struct l2cap_chan *l2cap_global_fixed_chan(struct l2cap_chan *c,
8050 struct hci_conn *hcon)
8051{
8052 u8 src_type = bdaddr_src_type(hcon);
8053
8054 read_lock(&chan_list_lock);
8055
8056 if (c)
8057 c = list_next_entry(c, global_l);
8058 else
8059 c = list_entry(chan_list.next, typeof(*c), global_l);
8060
8061 list_for_each_entry_from(c, &chan_list, global_l) {
8062 if (c->chan_type != L2CAP_CHAN_FIXED)
8063 continue;
8064 if (c->state != BT_LISTEN)
8065 continue;
8066 if (bacmp(&c->src, &hcon->src) && bacmp(&c->src, BDADDR_ANY))
8067 continue;
8068 if (src_type != c->src_type)
8069 continue;
8070
8071 l2cap_chan_hold(c);
8072 read_unlock(&chan_list_lock);
8073 return c;
8074 }
8075
8076 read_unlock(&chan_list_lock);
8077
8078 return NULL;
8079}
8080
8081static void l2cap_connect_cfm(struct hci_conn *hcon, u8 status)
8082{
8083 struct hci_dev *hdev = hcon->hdev;
8084 struct l2cap_conn *conn;
8085 struct l2cap_chan *pchan;
8086 u8 dst_type;
8087
8088 if (hcon->type != ACL_LINK && hcon->type != LE_LINK)
8089 return;
8090
8091 BT_DBG("hcon %p bdaddr %pMR status %d", hcon, &hcon->dst, status);
8092
8093 if (status) {
8094 l2cap_conn_del(hcon, bt_to_errno(status));
8095 return;
8096 }
8097
8098 conn = l2cap_conn_add(hcon);
8099 if (!conn)
8100 return;
8101
8102 dst_type = bdaddr_dst_type(hcon);
8103
8104 /* If device is blocked, do not create channels for it */
8105 if (hci_bdaddr_list_lookup(&hdev->blacklist, &hcon->dst, dst_type))
8106 return;
8107
8108 /* Find fixed channels and notify them of the new connection. We
8109 * use multiple individual lookups, continuing each time where
8110 * we left off, because the list lock would prevent calling the
8111 * potentially sleeping l2cap_chan_lock() function.
8112 */
8113 pchan = l2cap_global_fixed_chan(NULL, hcon);
8114 while (pchan) {
8115 struct l2cap_chan *chan, *next;
8116
8117 /* Client fixed channels should override server ones */
8118 if (__l2cap_get_chan_by_dcid(conn, pchan->scid))
8119 goto next;
8120
8121 l2cap_chan_lock(pchan);
8122 chan = pchan->ops->new_connection(pchan);
8123 if (chan) {
8124 bacpy(&chan->src, &hcon->src);
8125 bacpy(&chan->dst, &hcon->dst);
8126 chan->src_type = bdaddr_src_type(hcon);
8127 chan->dst_type = dst_type;
8128
8129 __l2cap_chan_add(conn, chan);
8130 }
8131
8132 l2cap_chan_unlock(pchan);
8133next:
8134 next = l2cap_global_fixed_chan(pchan, hcon);
8135 l2cap_chan_put(pchan);
8136 pchan = next;
8137 }
8138
8139 l2cap_conn_ready(conn);
8140}
8141
8142int l2cap_disconn_ind(struct hci_conn *hcon)
8143{
8144 struct l2cap_conn *conn = hcon->l2cap_data;
8145
8146 BT_DBG("hcon %p", hcon);
8147
8148 if (!conn)
8149 return HCI_ERROR_REMOTE_USER_TERM;
8150 return conn->disc_reason;
8151}
8152
8153static void l2cap_disconn_cfm(struct hci_conn *hcon, u8 reason)
8154{
8155 if (hcon->type != ACL_LINK && hcon->type != LE_LINK)
8156 return;
8157
8158 BT_DBG("hcon %p reason %d", hcon, reason);
8159
8160 l2cap_conn_del(hcon, bt_to_errno(reason));
8161}
8162
8163static inline void l2cap_check_encryption(struct l2cap_chan *chan, u8 encrypt)
8164{
8165 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED)
8166 return;
8167
8168 if (encrypt == 0x00) {
8169 if (chan->sec_level == BT_SECURITY_MEDIUM) {
8170 __set_chan_timer(chan, L2CAP_ENC_TIMEOUT);
8171 } else if (chan->sec_level == BT_SECURITY_HIGH ||
8172 chan->sec_level == BT_SECURITY_FIPS)
8173 l2cap_chan_close(chan, ECONNREFUSED);
8174 } else {
8175 if (chan->sec_level == BT_SECURITY_MEDIUM)
8176 __clear_chan_timer(chan);
8177 }
8178}
8179
8180static void l2cap_security_cfm(struct hci_conn *hcon, u8 status, u8 encrypt)
8181{
8182 struct l2cap_conn *conn = hcon->l2cap_data;
8183 struct l2cap_chan *chan;
8184
8185 if (!conn)
8186 return;
8187
8188 BT_DBG("conn %p status 0x%2.2x encrypt %u", conn, status, encrypt);
8189
8190 mutex_lock(&conn->chan_lock);
8191
8192 list_for_each_entry(chan, &conn->chan_l, list) {
8193 l2cap_chan_lock(chan);
8194
8195 BT_DBG("chan %p scid 0x%4.4x state %s", chan, chan->scid,
8196 state_to_string(chan->state));
8197
8198 if (chan->scid == L2CAP_CID_A2MP) {
8199 l2cap_chan_unlock(chan);
8200 continue;
8201 }
8202
8203 if (!status && encrypt)
8204 chan->sec_level = hcon->sec_level;
8205
8206 if (!__l2cap_no_conn_pending(chan)) {
8207 l2cap_chan_unlock(chan);
8208 continue;
8209 }
8210
8211 if (!status && (chan->state == BT_CONNECTED ||
8212 chan->state == BT_CONFIG)) {
8213 chan->ops->resume(chan);
8214 l2cap_check_encryption(chan, encrypt);
8215 l2cap_chan_unlock(chan);
8216 continue;
8217 }
8218
8219 if (chan->state == BT_CONNECT) {
8220 if (!status && l2cap_check_enc_key_size(hcon))
8221 l2cap_start_connection(chan);
8222 else
8223 __set_chan_timer(chan, L2CAP_DISC_TIMEOUT);
8224 } else if (chan->state == BT_CONNECT2 &&
8225 !(chan->mode == L2CAP_MODE_EXT_FLOWCTL ||
8226 chan->mode == L2CAP_MODE_LE_FLOWCTL)) {
8227 struct l2cap_conn_rsp rsp;
8228 __u16 res, stat;
8229
8230 if (!status && l2cap_check_enc_key_size(hcon)) {
8231 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) {
8232 res = L2CAP_CR_PEND;
8233 stat = L2CAP_CS_AUTHOR_PEND;
8234 chan->ops->defer(chan);
8235 } else {
8236 l2cap_state_change(chan, BT_CONFIG);
8237 res = L2CAP_CR_SUCCESS;
8238 stat = L2CAP_CS_NO_INFO;
8239 }
8240 } else {
8241 l2cap_state_change(chan, BT_DISCONN);
8242 __set_chan_timer(chan, L2CAP_DISC_TIMEOUT);
8243 res = L2CAP_CR_SEC_BLOCK;
8244 stat = L2CAP_CS_NO_INFO;
8245 }
8246
8247 rsp.scid = cpu_to_le16(chan->dcid);
8248 rsp.dcid = cpu_to_le16(chan->scid);
8249 rsp.result = cpu_to_le16(res);
8250 rsp.status = cpu_to_le16(stat);
8251 l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_RSP,
8252 sizeof(rsp), &rsp);
8253
8254 if (!test_bit(CONF_REQ_SENT, &chan->conf_state) &&
8255 res == L2CAP_CR_SUCCESS) {
8256 char buf[128];
8257 set_bit(CONF_REQ_SENT, &chan->conf_state);
8258 l2cap_send_cmd(conn, l2cap_get_ident(conn),
8259 L2CAP_CONF_REQ,
8260 l2cap_build_conf_req(chan, buf, sizeof(buf)),
8261 buf);
8262 chan->num_conf_req++;
8263 }
8264 }
8265
8266 l2cap_chan_unlock(chan);
8267 }
8268
8269 mutex_unlock(&conn->chan_lock);
8270}
8271
8272void l2cap_recv_acldata(struct hci_conn *hcon, struct sk_buff *skb, u16 flags)
8273{
8274 struct l2cap_conn *conn = hcon->l2cap_data;
8275 struct l2cap_hdr *hdr;
8276 int len;
8277
8278 /* For AMP controller do not create l2cap conn */
8279 if (!conn && hcon->hdev->dev_type != HCI_PRIMARY)
8280 goto drop;
8281
8282 if (!conn)
8283 conn = l2cap_conn_add(hcon);
8284
8285 if (!conn)
8286 goto drop;
8287
8288 BT_DBG("conn %p len %d flags 0x%x", conn, skb->len, flags);
8289
8290 switch (flags) {
8291 case ACL_START:
8292 case ACL_START_NO_FLUSH:
8293 case ACL_COMPLETE:
8294 if (conn->rx_len) {
8295 BT_ERR("Unexpected start frame (len %d)", skb->len);
8296 kfree_skb(conn->rx_skb);
8297 conn->rx_skb = NULL;
8298 conn->rx_len = 0;
8299 l2cap_conn_unreliable(conn, ECOMM);
8300 }
8301
8302 /* Start fragment always begin with Basic L2CAP header */
8303 if (skb->len < L2CAP_HDR_SIZE) {
8304 BT_ERR("Frame is too short (len %d)", skb->len);
8305 l2cap_conn_unreliable(conn, ECOMM);
8306 goto drop;
8307 }
8308
8309 hdr = (struct l2cap_hdr *) skb->data;
8310 len = __le16_to_cpu(hdr->len) + L2CAP_HDR_SIZE;
8311
8312 if (len == skb->len) {
8313 /* Complete frame received */
8314 l2cap_recv_frame(conn, skb);
8315 return;
8316 }
8317
8318 BT_DBG("Start: total len %d, frag len %d", len, skb->len);
8319
8320 if (skb->len > len) {
8321 BT_ERR("Frame is too long (len %d, expected len %d)",
8322 skb->len, len);
8323 l2cap_conn_unreliable(conn, ECOMM);
8324 goto drop;
8325 }
8326
8327 /* Allocate skb for the complete frame (with header) */
8328 conn->rx_skb = bt_skb_alloc(len, GFP_KERNEL);
8329 if (!conn->rx_skb)
8330 goto drop;
8331
8332 skb_copy_from_linear_data(skb, skb_put(conn->rx_skb, skb->len),
8333 skb->len);
8334 conn->rx_len = len - skb->len;
8335 break;
8336
8337 case ACL_CONT:
8338 BT_DBG("Cont: frag len %d (expecting %d)", skb->len, conn->rx_len);
8339
8340 if (!conn->rx_len) {
8341 BT_ERR("Unexpected continuation frame (len %d)", skb->len);
8342 l2cap_conn_unreliable(conn, ECOMM);
8343 goto drop;
8344 }
8345
8346 if (skb->len > conn->rx_len) {
8347 BT_ERR("Fragment is too long (len %d, expected %d)",
8348 skb->len, conn->rx_len);
8349 kfree_skb(conn->rx_skb);
8350 conn->rx_skb = NULL;
8351 conn->rx_len = 0;
8352 l2cap_conn_unreliable(conn, ECOMM);
8353 goto drop;
8354 }
8355
8356 skb_copy_from_linear_data(skb, skb_put(conn->rx_skb, skb->len),
8357 skb->len);
8358 conn->rx_len -= skb->len;
8359
8360 if (!conn->rx_len) {
8361 /* Complete frame received. l2cap_recv_frame
8362 * takes ownership of the skb so set the global
8363 * rx_skb pointer to NULL first.
8364 */
8365 struct sk_buff *rx_skb = conn->rx_skb;
8366 conn->rx_skb = NULL;
8367 l2cap_recv_frame(conn, rx_skb);
8368 }
8369 break;
8370 }
8371
8372drop:
8373 kfree_skb(skb);
8374}
8375
8376static struct hci_cb l2cap_cb = {
8377 .name = "L2CAP",
8378 .connect_cfm = l2cap_connect_cfm,
8379 .disconn_cfm = l2cap_disconn_cfm,
8380 .security_cfm = l2cap_security_cfm,
8381};
8382
8383static int l2cap_debugfs_show(struct seq_file *f, void *p)
8384{
8385 struct l2cap_chan *c;
8386
8387 read_lock(&chan_list_lock);
8388
8389 list_for_each_entry(c, &chan_list, global_l) {
8390 seq_printf(f, "%pMR (%u) %pMR (%u) %d %d 0x%4.4x 0x%4.4x %d %d %d %d\n",
8391 &c->src, c->src_type, &c->dst, c->dst_type,
8392 c->state, __le16_to_cpu(c->psm),
8393 c->scid, c->dcid, c->imtu, c->omtu,
8394 c->sec_level, c->mode);
8395 }
8396
8397 read_unlock(&chan_list_lock);
8398
8399 return 0;
8400}
8401
8402DEFINE_SHOW_ATTRIBUTE(l2cap_debugfs);
8403
8404static struct dentry *l2cap_debugfs;
8405
8406int __init l2cap_init(void)
8407{
8408 int err;
8409
8410 err = l2cap_init_sockets();
8411 if (err < 0)
8412 return err;
8413
8414 hci_register_cb(&l2cap_cb);
8415
8416 if (IS_ERR_OR_NULL(bt_debugfs))
8417 return 0;
8418
8419 l2cap_debugfs = debugfs_create_file("l2cap", 0444, bt_debugfs,
8420 NULL, &l2cap_debugfs_fops);
8421
8422 return 0;
8423}
8424
8425void l2cap_exit(void)
8426{
8427 debugfs_remove(l2cap_debugfs);
8428 hci_unregister_cb(&l2cap_cb);
8429 l2cap_cleanup_sockets();
8430}
8431
8432module_param(disable_ertm, bool, 0644);
8433MODULE_PARM_DESC(disable_ertm, "Disable enhanced retransmission mode");
8434
8435module_param(enable_ecred, bool, 0644);
8436MODULE_PARM_DESC(enable_ecred, "Enable enhanced credit flow control mode");