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