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1/*
2 BlueZ - Bluetooth protocol stack for Linux
3 Copyright (C) 2000-2001 Qualcomm Incorporated
4 Copyright (C) 2009-2010 Gustavo F. Padovan <gustavo@padovan.org>
5 Copyright (C) 2010 Google Inc.
6 Copyright (C) 2011 ProFUSION Embedded Systems
7 Copyright (c) 2012 Code Aurora Forum. All rights reserved.
8
9 Written 2000,2001 by Maxim Krasnyansky <maxk@qualcomm.com>
10
11 This program is free software; you can redistribute it and/or modify
12 it under the terms of the GNU General Public License version 2 as
13 published by the Free Software Foundation;
14
15 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
16 OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS.
18 IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) AND AUTHOR(S) BE LIABLE FOR ANY
19 CLAIM, OR ANY SPECIAL INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES
20 WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
21 ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
22 OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
23
24 ALL LIABILITY, INCLUDING LIABILITY FOR INFRINGEMENT OF ANY PATENTS,
25 COPYRIGHTS, TRADEMARKS OR OTHER RIGHTS, RELATING TO USE OF THIS
26 SOFTWARE IS DISCLAIMED.
27*/
28
29/* Bluetooth L2CAP core. */
30
31#include <linux/module.h>
32
33#include <linux/debugfs.h>
34#include <linux/crc16.h>
35#include <linux/filter.h>
36
37#include <net/bluetooth/bluetooth.h>
38#include <net/bluetooth/hci_core.h>
39#include <net/bluetooth/l2cap.h>
40
41#include "smp.h"
42#include "a2mp.h"
43#include "amp.h"
44
45#define LE_FLOWCTL_MAX_CREDITS 65535
46
47bool disable_ertm;
48
49static u32 l2cap_feat_mask = L2CAP_FEAT_FIXED_CHAN | L2CAP_FEAT_UCD;
50
51static LIST_HEAD(chan_list);
52static DEFINE_RWLOCK(chan_list_lock);
53
54static struct sk_buff *l2cap_build_cmd(struct l2cap_conn *conn,
55 u8 code, u8 ident, u16 dlen, void *data);
56static void l2cap_send_cmd(struct l2cap_conn *conn, u8 ident, u8 code, u16 len,
57 void *data);
58static int l2cap_build_conf_req(struct l2cap_chan *chan, void *data, size_t data_size);
59static void l2cap_send_disconn_req(struct l2cap_chan *chan, int err);
60
61static void l2cap_tx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
62 struct sk_buff_head *skbs, u8 event);
63
64static inline u8 bdaddr_type(u8 link_type, u8 bdaddr_type)
65{
66 if (link_type == LE_LINK) {
67 if (bdaddr_type == ADDR_LE_DEV_PUBLIC)
68 return BDADDR_LE_PUBLIC;
69 else
70 return BDADDR_LE_RANDOM;
71 }
72
73 return BDADDR_BREDR;
74}
75
76static inline u8 bdaddr_src_type(struct hci_conn *hcon)
77{
78 return bdaddr_type(hcon->type, hcon->src_type);
79}
80
81static inline u8 bdaddr_dst_type(struct hci_conn *hcon)
82{
83 return bdaddr_type(hcon->type, hcon->dst_type);
84}
85
86/* ---- L2CAP channels ---- */
87
88static struct l2cap_chan *__l2cap_get_chan_by_dcid(struct l2cap_conn *conn,
89 u16 cid)
90{
91 struct l2cap_chan *c;
92
93 list_for_each_entry(c, &conn->chan_l, list) {
94 if (c->dcid == cid)
95 return c;
96 }
97 return NULL;
98}
99
100static struct l2cap_chan *__l2cap_get_chan_by_scid(struct l2cap_conn *conn,
101 u16 cid)
102{
103 struct l2cap_chan *c;
104
105 list_for_each_entry(c, &conn->chan_l, list) {
106 if (c->scid == cid)
107 return c;
108 }
109 return NULL;
110}
111
112/* Find channel with given SCID.
113 * Returns locked channel. */
114static struct l2cap_chan *l2cap_get_chan_by_scid(struct l2cap_conn *conn,
115 u16 cid)
116{
117 struct l2cap_chan *c;
118
119 mutex_lock(&conn->chan_lock);
120 c = __l2cap_get_chan_by_scid(conn, cid);
121 if (c)
122 l2cap_chan_lock(c);
123 mutex_unlock(&conn->chan_lock);
124
125 return c;
126}
127
128/* Find channel with given DCID.
129 * Returns locked channel.
130 */
131static struct l2cap_chan *l2cap_get_chan_by_dcid(struct l2cap_conn *conn,
132 u16 cid)
133{
134 struct l2cap_chan *c;
135
136 mutex_lock(&conn->chan_lock);
137 c = __l2cap_get_chan_by_dcid(conn, cid);
138 if (c)
139 l2cap_chan_lock(c);
140 mutex_unlock(&conn->chan_lock);
141
142 return c;
143}
144
145static struct l2cap_chan *__l2cap_get_chan_by_ident(struct l2cap_conn *conn,
146 u8 ident)
147{
148 struct l2cap_chan *c;
149
150 list_for_each_entry(c, &conn->chan_l, list) {
151 if (c->ident == ident)
152 return c;
153 }
154 return NULL;
155}
156
157static struct l2cap_chan *l2cap_get_chan_by_ident(struct l2cap_conn *conn,
158 u8 ident)
159{
160 struct l2cap_chan *c;
161
162 mutex_lock(&conn->chan_lock);
163 c = __l2cap_get_chan_by_ident(conn, ident);
164 if (c)
165 l2cap_chan_lock(c);
166 mutex_unlock(&conn->chan_lock);
167
168 return c;
169}
170
171static struct l2cap_chan *__l2cap_global_chan_by_addr(__le16 psm, bdaddr_t *src,
172 u8 src_type)
173{
174 struct l2cap_chan *c;
175
176 list_for_each_entry(c, &chan_list, global_l) {
177 if (src_type == BDADDR_BREDR && c->src_type != BDADDR_BREDR)
178 continue;
179
180 if (src_type != BDADDR_BREDR && c->src_type == BDADDR_BREDR)
181 continue;
182
183 if (c->sport == psm && !bacmp(&c->src, src))
184 return c;
185 }
186 return NULL;
187}
188
189int l2cap_add_psm(struct l2cap_chan *chan, bdaddr_t *src, __le16 psm)
190{
191 int err;
192
193 write_lock(&chan_list_lock);
194
195 if (psm && __l2cap_global_chan_by_addr(psm, src, chan->src_type)) {
196 err = -EADDRINUSE;
197 goto done;
198 }
199
200 if (psm) {
201 chan->psm = psm;
202 chan->sport = psm;
203 err = 0;
204 } else {
205 u16 p, start, end, incr;
206
207 if (chan->src_type == BDADDR_BREDR) {
208 start = L2CAP_PSM_DYN_START;
209 end = L2CAP_PSM_AUTO_END;
210 incr = 2;
211 } else {
212 start = L2CAP_PSM_LE_DYN_START;
213 end = L2CAP_PSM_LE_DYN_END;
214 incr = 1;
215 }
216
217 err = -EINVAL;
218 for (p = start; p <= end; p += incr)
219 if (!__l2cap_global_chan_by_addr(cpu_to_le16(p), src,
220 chan->src_type)) {
221 chan->psm = cpu_to_le16(p);
222 chan->sport = cpu_to_le16(p);
223 err = 0;
224 break;
225 }
226 }
227
228done:
229 write_unlock(&chan_list_lock);
230 return err;
231}
232EXPORT_SYMBOL_GPL(l2cap_add_psm);
233
234int l2cap_add_scid(struct l2cap_chan *chan, __u16 scid)
235{
236 write_lock(&chan_list_lock);
237
238 /* Override the defaults (which are for conn-oriented) */
239 chan->omtu = L2CAP_DEFAULT_MTU;
240 chan->chan_type = L2CAP_CHAN_FIXED;
241
242 chan->scid = scid;
243
244 write_unlock(&chan_list_lock);
245
246 return 0;
247}
248
249static u16 l2cap_alloc_cid(struct l2cap_conn *conn)
250{
251 u16 cid, dyn_end;
252
253 if (conn->hcon->type == LE_LINK)
254 dyn_end = L2CAP_CID_LE_DYN_END;
255 else
256 dyn_end = L2CAP_CID_DYN_END;
257
258 for (cid = L2CAP_CID_DYN_START; cid <= dyn_end; cid++) {
259 if (!__l2cap_get_chan_by_scid(conn, cid))
260 return cid;
261 }
262
263 return 0;
264}
265
266static void l2cap_state_change(struct l2cap_chan *chan, int state)
267{
268 BT_DBG("chan %p %s -> %s", chan, state_to_string(chan->state),
269 state_to_string(state));
270
271 chan->state = state;
272 chan->ops->state_change(chan, state, 0);
273}
274
275static inline void l2cap_state_change_and_error(struct l2cap_chan *chan,
276 int state, int err)
277{
278 chan->state = state;
279 chan->ops->state_change(chan, chan->state, err);
280}
281
282static inline void l2cap_chan_set_err(struct l2cap_chan *chan, int err)
283{
284 chan->ops->state_change(chan, chan->state, err);
285}
286
287static void __set_retrans_timer(struct l2cap_chan *chan)
288{
289 if (!delayed_work_pending(&chan->monitor_timer) &&
290 chan->retrans_timeout) {
291 l2cap_set_timer(chan, &chan->retrans_timer,
292 msecs_to_jiffies(chan->retrans_timeout));
293 }
294}
295
296static void __set_monitor_timer(struct l2cap_chan *chan)
297{
298 __clear_retrans_timer(chan);
299 if (chan->monitor_timeout) {
300 l2cap_set_timer(chan, &chan->monitor_timer,
301 msecs_to_jiffies(chan->monitor_timeout));
302 }
303}
304
305static struct sk_buff *l2cap_ertm_seq_in_queue(struct sk_buff_head *head,
306 u16 seq)
307{
308 struct sk_buff *skb;
309
310 skb_queue_walk(head, skb) {
311 if (bt_cb(skb)->l2cap.txseq == seq)
312 return skb;
313 }
314
315 return NULL;
316}
317
318/* ---- L2CAP sequence number lists ---- */
319
320/* For ERTM, ordered lists of sequence numbers must be tracked for
321 * SREJ requests that are received and for frames that are to be
322 * retransmitted. These seq_list functions implement a singly-linked
323 * list in an array, where membership in the list can also be checked
324 * in constant time. Items can also be added to the tail of the list
325 * and removed from the head in constant time, without further memory
326 * allocs or frees.
327 */
328
329static int l2cap_seq_list_init(struct l2cap_seq_list *seq_list, u16 size)
330{
331 size_t alloc_size, i;
332
333 /* Allocated size is a power of 2 to map sequence numbers
334 * (which may be up to 14 bits) in to a smaller array that is
335 * sized for the negotiated ERTM transmit windows.
336 */
337 alloc_size = roundup_pow_of_two(size);
338
339 seq_list->list = kmalloc_array(alloc_size, sizeof(u16), GFP_KERNEL);
340 if (!seq_list->list)
341 return -ENOMEM;
342
343 seq_list->mask = alloc_size - 1;
344 seq_list->head = L2CAP_SEQ_LIST_CLEAR;
345 seq_list->tail = L2CAP_SEQ_LIST_CLEAR;
346 for (i = 0; i < alloc_size; i++)
347 seq_list->list[i] = L2CAP_SEQ_LIST_CLEAR;
348
349 return 0;
350}
351
352static inline void l2cap_seq_list_free(struct l2cap_seq_list *seq_list)
353{
354 kfree(seq_list->list);
355}
356
357static inline bool l2cap_seq_list_contains(struct l2cap_seq_list *seq_list,
358 u16 seq)
359{
360 /* Constant-time check for list membership */
361 return seq_list->list[seq & seq_list->mask] != L2CAP_SEQ_LIST_CLEAR;
362}
363
364static inline u16 l2cap_seq_list_pop(struct l2cap_seq_list *seq_list)
365{
366 u16 seq = seq_list->head;
367 u16 mask = seq_list->mask;
368
369 seq_list->head = seq_list->list[seq & mask];
370 seq_list->list[seq & mask] = L2CAP_SEQ_LIST_CLEAR;
371
372 if (seq_list->head == L2CAP_SEQ_LIST_TAIL) {
373 seq_list->head = L2CAP_SEQ_LIST_CLEAR;
374 seq_list->tail = L2CAP_SEQ_LIST_CLEAR;
375 }
376
377 return seq;
378}
379
380static void l2cap_seq_list_clear(struct l2cap_seq_list *seq_list)
381{
382 u16 i;
383
384 if (seq_list->head == L2CAP_SEQ_LIST_CLEAR)
385 return;
386
387 for (i = 0; i <= seq_list->mask; i++)
388 seq_list->list[i] = L2CAP_SEQ_LIST_CLEAR;
389
390 seq_list->head = L2CAP_SEQ_LIST_CLEAR;
391 seq_list->tail = L2CAP_SEQ_LIST_CLEAR;
392}
393
394static void l2cap_seq_list_append(struct l2cap_seq_list *seq_list, u16 seq)
395{
396 u16 mask = seq_list->mask;
397
398 /* All appends happen in constant time */
399
400 if (seq_list->list[seq & mask] != L2CAP_SEQ_LIST_CLEAR)
401 return;
402
403 if (seq_list->tail == L2CAP_SEQ_LIST_CLEAR)
404 seq_list->head = seq;
405 else
406 seq_list->list[seq_list->tail & mask] = seq;
407
408 seq_list->tail = seq;
409 seq_list->list[seq & mask] = L2CAP_SEQ_LIST_TAIL;
410}
411
412static void l2cap_chan_timeout(struct work_struct *work)
413{
414 struct l2cap_chan *chan = container_of(work, struct l2cap_chan,
415 chan_timer.work);
416 struct l2cap_conn *conn = chan->conn;
417 int reason;
418
419 BT_DBG("chan %p state %s", chan, state_to_string(chan->state));
420
421 mutex_lock(&conn->chan_lock);
422 l2cap_chan_lock(chan);
423
424 if (chan->state == BT_CONNECTED || chan->state == BT_CONFIG)
425 reason = ECONNREFUSED;
426 else if (chan->state == BT_CONNECT &&
427 chan->sec_level != BT_SECURITY_SDP)
428 reason = ECONNREFUSED;
429 else
430 reason = ETIMEDOUT;
431
432 l2cap_chan_close(chan, reason);
433
434 l2cap_chan_unlock(chan);
435
436 chan->ops->close(chan);
437 mutex_unlock(&conn->chan_lock);
438
439 l2cap_chan_put(chan);
440}
441
442struct l2cap_chan *l2cap_chan_create(void)
443{
444 struct l2cap_chan *chan;
445
446 chan = kzalloc(sizeof(*chan), GFP_ATOMIC);
447 if (!chan)
448 return NULL;
449
450 mutex_init(&chan->lock);
451
452 /* Set default lock nesting level */
453 atomic_set(&chan->nesting, L2CAP_NESTING_NORMAL);
454
455 write_lock(&chan_list_lock);
456 list_add(&chan->global_l, &chan_list);
457 write_unlock(&chan_list_lock);
458
459 INIT_DELAYED_WORK(&chan->chan_timer, l2cap_chan_timeout);
460
461 chan->state = BT_OPEN;
462
463 kref_init(&chan->kref);
464
465 /* This flag is cleared in l2cap_chan_ready() */
466 set_bit(CONF_NOT_COMPLETE, &chan->conf_state);
467
468 BT_DBG("chan %p", chan);
469
470 return chan;
471}
472EXPORT_SYMBOL_GPL(l2cap_chan_create);
473
474static void l2cap_chan_destroy(struct kref *kref)
475{
476 struct l2cap_chan *chan = container_of(kref, struct l2cap_chan, kref);
477
478 BT_DBG("chan %p", chan);
479
480 write_lock(&chan_list_lock);
481 list_del(&chan->global_l);
482 write_unlock(&chan_list_lock);
483
484 kfree(chan);
485}
486
487void l2cap_chan_hold(struct l2cap_chan *c)
488{
489 BT_DBG("chan %p orig refcnt %d", c, kref_read(&c->kref));
490
491 kref_get(&c->kref);
492}
493
494void l2cap_chan_put(struct l2cap_chan *c)
495{
496 BT_DBG("chan %p orig refcnt %d", c, kref_read(&c->kref));
497
498 kref_put(&c->kref, l2cap_chan_destroy);
499}
500EXPORT_SYMBOL_GPL(l2cap_chan_put);
501
502void l2cap_chan_set_defaults(struct l2cap_chan *chan)
503{
504 chan->fcs = L2CAP_FCS_CRC16;
505 chan->max_tx = L2CAP_DEFAULT_MAX_TX;
506 chan->tx_win = L2CAP_DEFAULT_TX_WINDOW;
507 chan->tx_win_max = L2CAP_DEFAULT_TX_WINDOW;
508 chan->remote_max_tx = chan->max_tx;
509 chan->remote_tx_win = chan->tx_win;
510 chan->ack_win = L2CAP_DEFAULT_TX_WINDOW;
511 chan->sec_level = BT_SECURITY_LOW;
512 chan->flush_to = L2CAP_DEFAULT_FLUSH_TO;
513 chan->retrans_timeout = L2CAP_DEFAULT_RETRANS_TO;
514 chan->monitor_timeout = L2CAP_DEFAULT_MONITOR_TO;
515 chan->conf_state = 0;
516
517 set_bit(FLAG_FORCE_ACTIVE, &chan->flags);
518}
519EXPORT_SYMBOL_GPL(l2cap_chan_set_defaults);
520
521static void l2cap_le_flowctl_init(struct l2cap_chan *chan, u16 tx_credits)
522{
523 chan->sdu = NULL;
524 chan->sdu_last_frag = NULL;
525 chan->sdu_len = 0;
526 chan->tx_credits = tx_credits;
527 /* Derive MPS from connection MTU to stop HCI fragmentation */
528 chan->mps = min_t(u16, chan->imtu, chan->conn->mtu - L2CAP_HDR_SIZE);
529 /* Give enough credits for a full packet */
530 chan->rx_credits = (chan->imtu / chan->mps) + 1;
531
532 skb_queue_head_init(&chan->tx_q);
533}
534
535void __l2cap_chan_add(struct l2cap_conn *conn, struct l2cap_chan *chan)
536{
537 BT_DBG("conn %p, psm 0x%2.2x, dcid 0x%4.4x", conn,
538 __le16_to_cpu(chan->psm), chan->dcid);
539
540 conn->disc_reason = HCI_ERROR_REMOTE_USER_TERM;
541
542 chan->conn = conn;
543
544 switch (chan->chan_type) {
545 case L2CAP_CHAN_CONN_ORIENTED:
546 /* Alloc CID for connection-oriented socket */
547 chan->scid = l2cap_alloc_cid(conn);
548 if (conn->hcon->type == ACL_LINK)
549 chan->omtu = L2CAP_DEFAULT_MTU;
550 break;
551
552 case L2CAP_CHAN_CONN_LESS:
553 /* Connectionless socket */
554 chan->scid = L2CAP_CID_CONN_LESS;
555 chan->dcid = L2CAP_CID_CONN_LESS;
556 chan->omtu = L2CAP_DEFAULT_MTU;
557 break;
558
559 case L2CAP_CHAN_FIXED:
560 /* Caller will set CID and CID specific MTU values */
561 break;
562
563 default:
564 /* Raw socket can send/recv signalling messages only */
565 chan->scid = L2CAP_CID_SIGNALING;
566 chan->dcid = L2CAP_CID_SIGNALING;
567 chan->omtu = L2CAP_DEFAULT_MTU;
568 }
569
570 chan->local_id = L2CAP_BESTEFFORT_ID;
571 chan->local_stype = L2CAP_SERV_BESTEFFORT;
572 chan->local_msdu = L2CAP_DEFAULT_MAX_SDU_SIZE;
573 chan->local_sdu_itime = L2CAP_DEFAULT_SDU_ITIME;
574 chan->local_acc_lat = L2CAP_DEFAULT_ACC_LAT;
575 chan->local_flush_to = L2CAP_EFS_DEFAULT_FLUSH_TO;
576
577 l2cap_chan_hold(chan);
578
579 /* Only keep a reference for fixed channels if they requested it */
580 if (chan->chan_type != L2CAP_CHAN_FIXED ||
581 test_bit(FLAG_HOLD_HCI_CONN, &chan->flags))
582 hci_conn_hold(conn->hcon);
583
584 list_add(&chan->list, &conn->chan_l);
585}
586
587void l2cap_chan_add(struct l2cap_conn *conn, struct l2cap_chan *chan)
588{
589 mutex_lock(&conn->chan_lock);
590 __l2cap_chan_add(conn, chan);
591 mutex_unlock(&conn->chan_lock);
592}
593
594void l2cap_chan_del(struct l2cap_chan *chan, int err)
595{
596 struct l2cap_conn *conn = chan->conn;
597
598 __clear_chan_timer(chan);
599
600 BT_DBG("chan %p, conn %p, err %d, state %s", chan, conn, err,
601 state_to_string(chan->state));
602
603 chan->ops->teardown(chan, err);
604
605 if (conn) {
606 struct amp_mgr *mgr = conn->hcon->amp_mgr;
607 /* Delete from channel list */
608 list_del(&chan->list);
609
610 l2cap_chan_put(chan);
611
612 chan->conn = NULL;
613
614 /* Reference was only held for non-fixed channels or
615 * fixed channels that explicitly requested it using the
616 * FLAG_HOLD_HCI_CONN flag.
617 */
618 if (chan->chan_type != L2CAP_CHAN_FIXED ||
619 test_bit(FLAG_HOLD_HCI_CONN, &chan->flags))
620 hci_conn_drop(conn->hcon);
621
622 if (mgr && mgr->bredr_chan == chan)
623 mgr->bredr_chan = NULL;
624 }
625
626 if (chan->hs_hchan) {
627 struct hci_chan *hs_hchan = chan->hs_hchan;
628
629 BT_DBG("chan %p disconnect hs_hchan %p", chan, hs_hchan);
630 amp_disconnect_logical_link(hs_hchan);
631 }
632
633 if (test_bit(CONF_NOT_COMPLETE, &chan->conf_state))
634 return;
635
636 switch(chan->mode) {
637 case L2CAP_MODE_BASIC:
638 break;
639
640 case L2CAP_MODE_LE_FLOWCTL:
641 skb_queue_purge(&chan->tx_q);
642 break;
643
644 case L2CAP_MODE_ERTM:
645 __clear_retrans_timer(chan);
646 __clear_monitor_timer(chan);
647 __clear_ack_timer(chan);
648
649 skb_queue_purge(&chan->srej_q);
650
651 l2cap_seq_list_free(&chan->srej_list);
652 l2cap_seq_list_free(&chan->retrans_list);
653
654 /* fall through */
655
656 case L2CAP_MODE_STREAMING:
657 skb_queue_purge(&chan->tx_q);
658 break;
659 }
660
661 return;
662}
663EXPORT_SYMBOL_GPL(l2cap_chan_del);
664
665static void l2cap_conn_update_id_addr(struct work_struct *work)
666{
667 struct l2cap_conn *conn = container_of(work, struct l2cap_conn,
668 id_addr_update_work);
669 struct hci_conn *hcon = conn->hcon;
670 struct l2cap_chan *chan;
671
672 mutex_lock(&conn->chan_lock);
673
674 list_for_each_entry(chan, &conn->chan_l, list) {
675 l2cap_chan_lock(chan);
676 bacpy(&chan->dst, &hcon->dst);
677 chan->dst_type = bdaddr_dst_type(hcon);
678 l2cap_chan_unlock(chan);
679 }
680
681 mutex_unlock(&conn->chan_lock);
682}
683
684static void l2cap_chan_le_connect_reject(struct l2cap_chan *chan)
685{
686 struct l2cap_conn *conn = chan->conn;
687 struct l2cap_le_conn_rsp rsp;
688 u16 result;
689
690 if (test_bit(FLAG_DEFER_SETUP, &chan->flags))
691 result = L2CAP_CR_LE_AUTHORIZATION;
692 else
693 result = L2CAP_CR_LE_BAD_PSM;
694
695 l2cap_state_change(chan, BT_DISCONN);
696
697 rsp.dcid = cpu_to_le16(chan->scid);
698 rsp.mtu = cpu_to_le16(chan->imtu);
699 rsp.mps = cpu_to_le16(chan->mps);
700 rsp.credits = cpu_to_le16(chan->rx_credits);
701 rsp.result = cpu_to_le16(result);
702
703 l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CONN_RSP, sizeof(rsp),
704 &rsp);
705}
706
707static void l2cap_chan_connect_reject(struct l2cap_chan *chan)
708{
709 struct l2cap_conn *conn = chan->conn;
710 struct l2cap_conn_rsp rsp;
711 u16 result;
712
713 if (test_bit(FLAG_DEFER_SETUP, &chan->flags))
714 result = L2CAP_CR_SEC_BLOCK;
715 else
716 result = L2CAP_CR_BAD_PSM;
717
718 l2cap_state_change(chan, BT_DISCONN);
719
720 rsp.scid = cpu_to_le16(chan->dcid);
721 rsp.dcid = cpu_to_le16(chan->scid);
722 rsp.result = cpu_to_le16(result);
723 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
724
725 l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_RSP, sizeof(rsp), &rsp);
726}
727
728void l2cap_chan_close(struct l2cap_chan *chan, int reason)
729{
730 struct l2cap_conn *conn = chan->conn;
731
732 BT_DBG("chan %p state %s", chan, state_to_string(chan->state));
733
734 switch (chan->state) {
735 case BT_LISTEN:
736 chan->ops->teardown(chan, 0);
737 break;
738
739 case BT_CONNECTED:
740 case BT_CONFIG:
741 if (chan->chan_type == L2CAP_CHAN_CONN_ORIENTED) {
742 __set_chan_timer(chan, chan->ops->get_sndtimeo(chan));
743 l2cap_send_disconn_req(chan, reason);
744 } else
745 l2cap_chan_del(chan, reason);
746 break;
747
748 case BT_CONNECT2:
749 if (chan->chan_type == L2CAP_CHAN_CONN_ORIENTED) {
750 if (conn->hcon->type == ACL_LINK)
751 l2cap_chan_connect_reject(chan);
752 else if (conn->hcon->type == LE_LINK)
753 l2cap_chan_le_connect_reject(chan);
754 }
755
756 l2cap_chan_del(chan, reason);
757 break;
758
759 case BT_CONNECT:
760 case BT_DISCONN:
761 l2cap_chan_del(chan, reason);
762 break;
763
764 default:
765 chan->ops->teardown(chan, 0);
766 break;
767 }
768}
769EXPORT_SYMBOL(l2cap_chan_close);
770
771static inline u8 l2cap_get_auth_type(struct l2cap_chan *chan)
772{
773 switch (chan->chan_type) {
774 case L2CAP_CHAN_RAW:
775 switch (chan->sec_level) {
776 case BT_SECURITY_HIGH:
777 case BT_SECURITY_FIPS:
778 return HCI_AT_DEDICATED_BONDING_MITM;
779 case BT_SECURITY_MEDIUM:
780 return HCI_AT_DEDICATED_BONDING;
781 default:
782 return HCI_AT_NO_BONDING;
783 }
784 break;
785 case L2CAP_CHAN_CONN_LESS:
786 if (chan->psm == cpu_to_le16(L2CAP_PSM_3DSP)) {
787 if (chan->sec_level == BT_SECURITY_LOW)
788 chan->sec_level = BT_SECURITY_SDP;
789 }
790 if (chan->sec_level == BT_SECURITY_HIGH ||
791 chan->sec_level == BT_SECURITY_FIPS)
792 return HCI_AT_NO_BONDING_MITM;
793 else
794 return HCI_AT_NO_BONDING;
795 break;
796 case L2CAP_CHAN_CONN_ORIENTED:
797 if (chan->psm == cpu_to_le16(L2CAP_PSM_SDP)) {
798 if (chan->sec_level == BT_SECURITY_LOW)
799 chan->sec_level = BT_SECURITY_SDP;
800
801 if (chan->sec_level == BT_SECURITY_HIGH ||
802 chan->sec_level == BT_SECURITY_FIPS)
803 return HCI_AT_NO_BONDING_MITM;
804 else
805 return HCI_AT_NO_BONDING;
806 }
807 /* fall through */
808 default:
809 switch (chan->sec_level) {
810 case BT_SECURITY_HIGH:
811 case BT_SECURITY_FIPS:
812 return HCI_AT_GENERAL_BONDING_MITM;
813 case BT_SECURITY_MEDIUM:
814 return HCI_AT_GENERAL_BONDING;
815 default:
816 return HCI_AT_NO_BONDING;
817 }
818 break;
819 }
820}
821
822/* Service level security */
823int l2cap_chan_check_security(struct l2cap_chan *chan, bool initiator)
824{
825 struct l2cap_conn *conn = chan->conn;
826 __u8 auth_type;
827
828 if (conn->hcon->type == LE_LINK)
829 return smp_conn_security(conn->hcon, chan->sec_level);
830
831 auth_type = l2cap_get_auth_type(chan);
832
833 return hci_conn_security(conn->hcon, chan->sec_level, auth_type,
834 initiator);
835}
836
837static u8 l2cap_get_ident(struct l2cap_conn *conn)
838{
839 u8 id;
840
841 /* Get next available identificator.
842 * 1 - 128 are used by kernel.
843 * 129 - 199 are reserved.
844 * 200 - 254 are used by utilities like l2ping, etc.
845 */
846
847 mutex_lock(&conn->ident_lock);
848
849 if (++conn->tx_ident > 128)
850 conn->tx_ident = 1;
851
852 id = conn->tx_ident;
853
854 mutex_unlock(&conn->ident_lock);
855
856 return id;
857}
858
859static void l2cap_send_cmd(struct l2cap_conn *conn, u8 ident, u8 code, u16 len,
860 void *data)
861{
862 struct sk_buff *skb = l2cap_build_cmd(conn, code, ident, len, data);
863 u8 flags;
864
865 BT_DBG("code 0x%2.2x", code);
866
867 if (!skb)
868 return;
869
870 /* Use NO_FLUSH if supported or we have an LE link (which does
871 * not support auto-flushing packets) */
872 if (lmp_no_flush_capable(conn->hcon->hdev) ||
873 conn->hcon->type == LE_LINK)
874 flags = ACL_START_NO_FLUSH;
875 else
876 flags = ACL_START;
877
878 bt_cb(skb)->force_active = BT_POWER_FORCE_ACTIVE_ON;
879 skb->priority = HCI_PRIO_MAX;
880
881 hci_send_acl(conn->hchan, skb, flags);
882}
883
884static bool __chan_is_moving(struct l2cap_chan *chan)
885{
886 return chan->move_state != L2CAP_MOVE_STABLE &&
887 chan->move_state != L2CAP_MOVE_WAIT_PREPARE;
888}
889
890static void l2cap_do_send(struct l2cap_chan *chan, struct sk_buff *skb)
891{
892 struct hci_conn *hcon = chan->conn->hcon;
893 u16 flags;
894
895 BT_DBG("chan %p, skb %p len %d priority %u", chan, skb, skb->len,
896 skb->priority);
897
898 if (chan->hs_hcon && !__chan_is_moving(chan)) {
899 if (chan->hs_hchan)
900 hci_send_acl(chan->hs_hchan, skb, ACL_COMPLETE);
901 else
902 kfree_skb(skb);
903
904 return;
905 }
906
907 /* Use NO_FLUSH for LE links (where this is the only option) or
908 * if the BR/EDR link supports it and flushing has not been
909 * explicitly requested (through FLAG_FLUSHABLE).
910 */
911 if (hcon->type == LE_LINK ||
912 (!test_bit(FLAG_FLUSHABLE, &chan->flags) &&
913 lmp_no_flush_capable(hcon->hdev)))
914 flags = ACL_START_NO_FLUSH;
915 else
916 flags = ACL_START;
917
918 bt_cb(skb)->force_active = test_bit(FLAG_FORCE_ACTIVE, &chan->flags);
919 hci_send_acl(chan->conn->hchan, skb, flags);
920}
921
922static void __unpack_enhanced_control(u16 enh, struct l2cap_ctrl *control)
923{
924 control->reqseq = (enh & L2CAP_CTRL_REQSEQ) >> L2CAP_CTRL_REQSEQ_SHIFT;
925 control->final = (enh & L2CAP_CTRL_FINAL) >> L2CAP_CTRL_FINAL_SHIFT;
926
927 if (enh & L2CAP_CTRL_FRAME_TYPE) {
928 /* S-Frame */
929 control->sframe = 1;
930 control->poll = (enh & L2CAP_CTRL_POLL) >> L2CAP_CTRL_POLL_SHIFT;
931 control->super = (enh & L2CAP_CTRL_SUPERVISE) >> L2CAP_CTRL_SUPER_SHIFT;
932
933 control->sar = 0;
934 control->txseq = 0;
935 } else {
936 /* I-Frame */
937 control->sframe = 0;
938 control->sar = (enh & L2CAP_CTRL_SAR) >> L2CAP_CTRL_SAR_SHIFT;
939 control->txseq = (enh & L2CAP_CTRL_TXSEQ) >> L2CAP_CTRL_TXSEQ_SHIFT;
940
941 control->poll = 0;
942 control->super = 0;
943 }
944}
945
946static void __unpack_extended_control(u32 ext, struct l2cap_ctrl *control)
947{
948 control->reqseq = (ext & L2CAP_EXT_CTRL_REQSEQ) >> L2CAP_EXT_CTRL_REQSEQ_SHIFT;
949 control->final = (ext & L2CAP_EXT_CTRL_FINAL) >> L2CAP_EXT_CTRL_FINAL_SHIFT;
950
951 if (ext & L2CAP_EXT_CTRL_FRAME_TYPE) {
952 /* S-Frame */
953 control->sframe = 1;
954 control->poll = (ext & L2CAP_EXT_CTRL_POLL) >> L2CAP_EXT_CTRL_POLL_SHIFT;
955 control->super = (ext & L2CAP_EXT_CTRL_SUPERVISE) >> L2CAP_EXT_CTRL_SUPER_SHIFT;
956
957 control->sar = 0;
958 control->txseq = 0;
959 } else {
960 /* I-Frame */
961 control->sframe = 0;
962 control->sar = (ext & L2CAP_EXT_CTRL_SAR) >> L2CAP_EXT_CTRL_SAR_SHIFT;
963 control->txseq = (ext & L2CAP_EXT_CTRL_TXSEQ) >> L2CAP_EXT_CTRL_TXSEQ_SHIFT;
964
965 control->poll = 0;
966 control->super = 0;
967 }
968}
969
970static inline void __unpack_control(struct l2cap_chan *chan,
971 struct sk_buff *skb)
972{
973 if (test_bit(FLAG_EXT_CTRL, &chan->flags)) {
974 __unpack_extended_control(get_unaligned_le32(skb->data),
975 &bt_cb(skb)->l2cap);
976 skb_pull(skb, L2CAP_EXT_CTRL_SIZE);
977 } else {
978 __unpack_enhanced_control(get_unaligned_le16(skb->data),
979 &bt_cb(skb)->l2cap);
980 skb_pull(skb, L2CAP_ENH_CTRL_SIZE);
981 }
982}
983
984static u32 __pack_extended_control(struct l2cap_ctrl *control)
985{
986 u32 packed;
987
988 packed = control->reqseq << L2CAP_EXT_CTRL_REQSEQ_SHIFT;
989 packed |= control->final << L2CAP_EXT_CTRL_FINAL_SHIFT;
990
991 if (control->sframe) {
992 packed |= control->poll << L2CAP_EXT_CTRL_POLL_SHIFT;
993 packed |= control->super << L2CAP_EXT_CTRL_SUPER_SHIFT;
994 packed |= L2CAP_EXT_CTRL_FRAME_TYPE;
995 } else {
996 packed |= control->sar << L2CAP_EXT_CTRL_SAR_SHIFT;
997 packed |= control->txseq << L2CAP_EXT_CTRL_TXSEQ_SHIFT;
998 }
999
1000 return packed;
1001}
1002
1003static u16 __pack_enhanced_control(struct l2cap_ctrl *control)
1004{
1005 u16 packed;
1006
1007 packed = control->reqseq << L2CAP_CTRL_REQSEQ_SHIFT;
1008 packed |= control->final << L2CAP_CTRL_FINAL_SHIFT;
1009
1010 if (control->sframe) {
1011 packed |= control->poll << L2CAP_CTRL_POLL_SHIFT;
1012 packed |= control->super << L2CAP_CTRL_SUPER_SHIFT;
1013 packed |= L2CAP_CTRL_FRAME_TYPE;
1014 } else {
1015 packed |= control->sar << L2CAP_CTRL_SAR_SHIFT;
1016 packed |= control->txseq << L2CAP_CTRL_TXSEQ_SHIFT;
1017 }
1018
1019 return packed;
1020}
1021
1022static inline void __pack_control(struct l2cap_chan *chan,
1023 struct l2cap_ctrl *control,
1024 struct sk_buff *skb)
1025{
1026 if (test_bit(FLAG_EXT_CTRL, &chan->flags)) {
1027 put_unaligned_le32(__pack_extended_control(control),
1028 skb->data + L2CAP_HDR_SIZE);
1029 } else {
1030 put_unaligned_le16(__pack_enhanced_control(control),
1031 skb->data + L2CAP_HDR_SIZE);
1032 }
1033}
1034
1035static inline unsigned int __ertm_hdr_size(struct l2cap_chan *chan)
1036{
1037 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
1038 return L2CAP_EXT_HDR_SIZE;
1039 else
1040 return L2CAP_ENH_HDR_SIZE;
1041}
1042
1043static struct sk_buff *l2cap_create_sframe_pdu(struct l2cap_chan *chan,
1044 u32 control)
1045{
1046 struct sk_buff *skb;
1047 struct l2cap_hdr *lh;
1048 int hlen = __ertm_hdr_size(chan);
1049
1050 if (chan->fcs == L2CAP_FCS_CRC16)
1051 hlen += L2CAP_FCS_SIZE;
1052
1053 skb = bt_skb_alloc(hlen, GFP_KERNEL);
1054
1055 if (!skb)
1056 return ERR_PTR(-ENOMEM);
1057
1058 lh = skb_put(skb, L2CAP_HDR_SIZE);
1059 lh->len = cpu_to_le16(hlen - L2CAP_HDR_SIZE);
1060 lh->cid = cpu_to_le16(chan->dcid);
1061
1062 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
1063 put_unaligned_le32(control, skb_put(skb, L2CAP_EXT_CTRL_SIZE));
1064 else
1065 put_unaligned_le16(control, skb_put(skb, L2CAP_ENH_CTRL_SIZE));
1066
1067 if (chan->fcs == L2CAP_FCS_CRC16) {
1068 u16 fcs = crc16(0, (u8 *)skb->data, skb->len);
1069 put_unaligned_le16(fcs, skb_put(skb, L2CAP_FCS_SIZE));
1070 }
1071
1072 skb->priority = HCI_PRIO_MAX;
1073 return skb;
1074}
1075
1076static void l2cap_send_sframe(struct l2cap_chan *chan,
1077 struct l2cap_ctrl *control)
1078{
1079 struct sk_buff *skb;
1080 u32 control_field;
1081
1082 BT_DBG("chan %p, control %p", chan, control);
1083
1084 if (!control->sframe)
1085 return;
1086
1087 if (__chan_is_moving(chan))
1088 return;
1089
1090 if (test_and_clear_bit(CONN_SEND_FBIT, &chan->conn_state) &&
1091 !control->poll)
1092 control->final = 1;
1093
1094 if (control->super == L2CAP_SUPER_RR)
1095 clear_bit(CONN_RNR_SENT, &chan->conn_state);
1096 else if (control->super == L2CAP_SUPER_RNR)
1097 set_bit(CONN_RNR_SENT, &chan->conn_state);
1098
1099 if (control->super != L2CAP_SUPER_SREJ) {
1100 chan->last_acked_seq = control->reqseq;
1101 __clear_ack_timer(chan);
1102 }
1103
1104 BT_DBG("reqseq %d, final %d, poll %d, super %d", control->reqseq,
1105 control->final, control->poll, control->super);
1106
1107 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
1108 control_field = __pack_extended_control(control);
1109 else
1110 control_field = __pack_enhanced_control(control);
1111
1112 skb = l2cap_create_sframe_pdu(chan, control_field);
1113 if (!IS_ERR(skb))
1114 l2cap_do_send(chan, skb);
1115}
1116
1117static void l2cap_send_rr_or_rnr(struct l2cap_chan *chan, bool poll)
1118{
1119 struct l2cap_ctrl control;
1120
1121 BT_DBG("chan %p, poll %d", chan, poll);
1122
1123 memset(&control, 0, sizeof(control));
1124 control.sframe = 1;
1125 control.poll = poll;
1126
1127 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state))
1128 control.super = L2CAP_SUPER_RNR;
1129 else
1130 control.super = L2CAP_SUPER_RR;
1131
1132 control.reqseq = chan->buffer_seq;
1133 l2cap_send_sframe(chan, &control);
1134}
1135
1136static inline int __l2cap_no_conn_pending(struct l2cap_chan *chan)
1137{
1138 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED)
1139 return true;
1140
1141 return !test_bit(CONF_CONNECT_PEND, &chan->conf_state);
1142}
1143
1144static bool __amp_capable(struct l2cap_chan *chan)
1145{
1146 struct l2cap_conn *conn = chan->conn;
1147 struct hci_dev *hdev;
1148 bool amp_available = false;
1149
1150 if (!(conn->local_fixed_chan & L2CAP_FC_A2MP))
1151 return false;
1152
1153 if (!(conn->remote_fixed_chan & L2CAP_FC_A2MP))
1154 return false;
1155
1156 read_lock(&hci_dev_list_lock);
1157 list_for_each_entry(hdev, &hci_dev_list, list) {
1158 if (hdev->amp_type != AMP_TYPE_BREDR &&
1159 test_bit(HCI_UP, &hdev->flags)) {
1160 amp_available = true;
1161 break;
1162 }
1163 }
1164 read_unlock(&hci_dev_list_lock);
1165
1166 if (chan->chan_policy == BT_CHANNEL_POLICY_AMP_PREFERRED)
1167 return amp_available;
1168
1169 return false;
1170}
1171
1172static bool l2cap_check_efs(struct l2cap_chan *chan)
1173{
1174 /* Check EFS parameters */
1175 return true;
1176}
1177
1178void l2cap_send_conn_req(struct l2cap_chan *chan)
1179{
1180 struct l2cap_conn *conn = chan->conn;
1181 struct l2cap_conn_req req;
1182
1183 req.scid = cpu_to_le16(chan->scid);
1184 req.psm = chan->psm;
1185
1186 chan->ident = l2cap_get_ident(conn);
1187
1188 set_bit(CONF_CONNECT_PEND, &chan->conf_state);
1189
1190 l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_REQ, sizeof(req), &req);
1191}
1192
1193static void l2cap_send_create_chan_req(struct l2cap_chan *chan, u8 amp_id)
1194{
1195 struct l2cap_create_chan_req req;
1196 req.scid = cpu_to_le16(chan->scid);
1197 req.psm = chan->psm;
1198 req.amp_id = amp_id;
1199
1200 chan->ident = l2cap_get_ident(chan->conn);
1201
1202 l2cap_send_cmd(chan->conn, chan->ident, L2CAP_CREATE_CHAN_REQ,
1203 sizeof(req), &req);
1204}
1205
1206static void l2cap_move_setup(struct l2cap_chan *chan)
1207{
1208 struct sk_buff *skb;
1209
1210 BT_DBG("chan %p", chan);
1211
1212 if (chan->mode != L2CAP_MODE_ERTM)
1213 return;
1214
1215 __clear_retrans_timer(chan);
1216 __clear_monitor_timer(chan);
1217 __clear_ack_timer(chan);
1218
1219 chan->retry_count = 0;
1220 skb_queue_walk(&chan->tx_q, skb) {
1221 if (bt_cb(skb)->l2cap.retries)
1222 bt_cb(skb)->l2cap.retries = 1;
1223 else
1224 break;
1225 }
1226
1227 chan->expected_tx_seq = chan->buffer_seq;
1228
1229 clear_bit(CONN_REJ_ACT, &chan->conn_state);
1230 clear_bit(CONN_SREJ_ACT, &chan->conn_state);
1231 l2cap_seq_list_clear(&chan->retrans_list);
1232 l2cap_seq_list_clear(&chan->srej_list);
1233 skb_queue_purge(&chan->srej_q);
1234
1235 chan->tx_state = L2CAP_TX_STATE_XMIT;
1236 chan->rx_state = L2CAP_RX_STATE_MOVE;
1237
1238 set_bit(CONN_REMOTE_BUSY, &chan->conn_state);
1239}
1240
1241static void l2cap_move_done(struct l2cap_chan *chan)
1242{
1243 u8 move_role = chan->move_role;
1244 BT_DBG("chan %p", chan);
1245
1246 chan->move_state = L2CAP_MOVE_STABLE;
1247 chan->move_role = L2CAP_MOVE_ROLE_NONE;
1248
1249 if (chan->mode != L2CAP_MODE_ERTM)
1250 return;
1251
1252 switch (move_role) {
1253 case L2CAP_MOVE_ROLE_INITIATOR:
1254 l2cap_tx(chan, NULL, NULL, L2CAP_EV_EXPLICIT_POLL);
1255 chan->rx_state = L2CAP_RX_STATE_WAIT_F;
1256 break;
1257 case L2CAP_MOVE_ROLE_RESPONDER:
1258 chan->rx_state = L2CAP_RX_STATE_WAIT_P;
1259 break;
1260 }
1261}
1262
1263static void l2cap_chan_ready(struct l2cap_chan *chan)
1264{
1265 /* The channel may have already been flagged as connected in
1266 * case of receiving data before the L2CAP info req/rsp
1267 * procedure is complete.
1268 */
1269 if (chan->state == BT_CONNECTED)
1270 return;
1271
1272 /* This clears all conf flags, including CONF_NOT_COMPLETE */
1273 chan->conf_state = 0;
1274 __clear_chan_timer(chan);
1275
1276 if (chan->mode == L2CAP_MODE_LE_FLOWCTL && !chan->tx_credits)
1277 chan->ops->suspend(chan);
1278
1279 chan->state = BT_CONNECTED;
1280
1281 chan->ops->ready(chan);
1282}
1283
1284static void l2cap_le_connect(struct l2cap_chan *chan)
1285{
1286 struct l2cap_conn *conn = chan->conn;
1287 struct l2cap_le_conn_req req;
1288
1289 if (test_and_set_bit(FLAG_LE_CONN_REQ_SENT, &chan->flags))
1290 return;
1291
1292 l2cap_le_flowctl_init(chan, 0);
1293
1294 req.psm = chan->psm;
1295 req.scid = cpu_to_le16(chan->scid);
1296 req.mtu = cpu_to_le16(chan->imtu);
1297 req.mps = cpu_to_le16(chan->mps);
1298 req.credits = cpu_to_le16(chan->rx_credits);
1299
1300 chan->ident = l2cap_get_ident(conn);
1301
1302 l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CONN_REQ,
1303 sizeof(req), &req);
1304}
1305
1306static void l2cap_le_start(struct l2cap_chan *chan)
1307{
1308 struct l2cap_conn *conn = chan->conn;
1309
1310 if (!smp_conn_security(conn->hcon, chan->sec_level))
1311 return;
1312
1313 if (!chan->psm) {
1314 l2cap_chan_ready(chan);
1315 return;
1316 }
1317
1318 if (chan->state == BT_CONNECT)
1319 l2cap_le_connect(chan);
1320}
1321
1322static void l2cap_start_connection(struct l2cap_chan *chan)
1323{
1324 if (__amp_capable(chan)) {
1325 BT_DBG("chan %p AMP capable: discover AMPs", chan);
1326 a2mp_discover_amp(chan);
1327 } else if (chan->conn->hcon->type == LE_LINK) {
1328 l2cap_le_start(chan);
1329 } else {
1330 l2cap_send_conn_req(chan);
1331 }
1332}
1333
1334static void l2cap_request_info(struct l2cap_conn *conn)
1335{
1336 struct l2cap_info_req req;
1337
1338 if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT)
1339 return;
1340
1341 req.type = cpu_to_le16(L2CAP_IT_FEAT_MASK);
1342
1343 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_SENT;
1344 conn->info_ident = l2cap_get_ident(conn);
1345
1346 schedule_delayed_work(&conn->info_timer, L2CAP_INFO_TIMEOUT);
1347
1348 l2cap_send_cmd(conn, conn->info_ident, L2CAP_INFO_REQ,
1349 sizeof(req), &req);
1350}
1351
1352static bool l2cap_check_enc_key_size(struct hci_conn *hcon)
1353{
1354 /* The minimum encryption key size needs to be enforced by the
1355 * host stack before establishing any L2CAP connections. The
1356 * specification in theory allows a minimum of 1, but to align
1357 * BR/EDR and LE transports, a minimum of 7 is chosen.
1358 *
1359 * This check might also be called for unencrypted connections
1360 * that have no key size requirements. Ensure that the link is
1361 * actually encrypted before enforcing a key size.
1362 */
1363 return (!test_bit(HCI_CONN_ENCRYPT, &hcon->flags) ||
1364 hcon->enc_key_size >= hcon->hdev->min_enc_key_size);
1365}
1366
1367static void l2cap_do_start(struct l2cap_chan *chan)
1368{
1369 struct l2cap_conn *conn = chan->conn;
1370
1371 if (conn->hcon->type == LE_LINK) {
1372 l2cap_le_start(chan);
1373 return;
1374 }
1375
1376 if (!(conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT)) {
1377 l2cap_request_info(conn);
1378 return;
1379 }
1380
1381 if (!(conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE))
1382 return;
1383
1384 if (!l2cap_chan_check_security(chan, true) ||
1385 !__l2cap_no_conn_pending(chan))
1386 return;
1387
1388 if (l2cap_check_enc_key_size(conn->hcon))
1389 l2cap_start_connection(chan);
1390 else
1391 __set_chan_timer(chan, L2CAP_DISC_TIMEOUT);
1392}
1393
1394static inline int l2cap_mode_supported(__u8 mode, __u32 feat_mask)
1395{
1396 u32 local_feat_mask = l2cap_feat_mask;
1397 if (!disable_ertm)
1398 local_feat_mask |= L2CAP_FEAT_ERTM | L2CAP_FEAT_STREAMING;
1399
1400 switch (mode) {
1401 case L2CAP_MODE_ERTM:
1402 return L2CAP_FEAT_ERTM & feat_mask & local_feat_mask;
1403 case L2CAP_MODE_STREAMING:
1404 return L2CAP_FEAT_STREAMING & feat_mask & local_feat_mask;
1405 default:
1406 return 0x00;
1407 }
1408}
1409
1410static void l2cap_send_disconn_req(struct l2cap_chan *chan, int err)
1411{
1412 struct l2cap_conn *conn = chan->conn;
1413 struct l2cap_disconn_req req;
1414
1415 if (!conn)
1416 return;
1417
1418 if (chan->mode == L2CAP_MODE_ERTM && chan->state == BT_CONNECTED) {
1419 __clear_retrans_timer(chan);
1420 __clear_monitor_timer(chan);
1421 __clear_ack_timer(chan);
1422 }
1423
1424 if (chan->scid == L2CAP_CID_A2MP) {
1425 l2cap_state_change(chan, BT_DISCONN);
1426 return;
1427 }
1428
1429 req.dcid = cpu_to_le16(chan->dcid);
1430 req.scid = cpu_to_le16(chan->scid);
1431 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_DISCONN_REQ,
1432 sizeof(req), &req);
1433
1434 l2cap_state_change_and_error(chan, BT_DISCONN, err);
1435}
1436
1437/* ---- L2CAP connections ---- */
1438static void l2cap_conn_start(struct l2cap_conn *conn)
1439{
1440 struct l2cap_chan *chan, *tmp;
1441
1442 BT_DBG("conn %p", conn);
1443
1444 mutex_lock(&conn->chan_lock);
1445
1446 list_for_each_entry_safe(chan, tmp, &conn->chan_l, list) {
1447 l2cap_chan_lock(chan);
1448
1449 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) {
1450 l2cap_chan_ready(chan);
1451 l2cap_chan_unlock(chan);
1452 continue;
1453 }
1454
1455 if (chan->state == BT_CONNECT) {
1456 if (!l2cap_chan_check_security(chan, true) ||
1457 !__l2cap_no_conn_pending(chan)) {
1458 l2cap_chan_unlock(chan);
1459 continue;
1460 }
1461
1462 if (!l2cap_mode_supported(chan->mode, conn->feat_mask)
1463 && test_bit(CONF_STATE2_DEVICE,
1464 &chan->conf_state)) {
1465 l2cap_chan_close(chan, ECONNRESET);
1466 l2cap_chan_unlock(chan);
1467 continue;
1468 }
1469
1470 if (l2cap_check_enc_key_size(conn->hcon))
1471 l2cap_start_connection(chan);
1472 else
1473 l2cap_chan_close(chan, ECONNREFUSED);
1474
1475 } else if (chan->state == BT_CONNECT2) {
1476 struct l2cap_conn_rsp rsp;
1477 char buf[128];
1478 rsp.scid = cpu_to_le16(chan->dcid);
1479 rsp.dcid = cpu_to_le16(chan->scid);
1480
1481 if (l2cap_chan_check_security(chan, false)) {
1482 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) {
1483 rsp.result = cpu_to_le16(L2CAP_CR_PEND);
1484 rsp.status = cpu_to_le16(L2CAP_CS_AUTHOR_PEND);
1485 chan->ops->defer(chan);
1486
1487 } else {
1488 l2cap_state_change(chan, BT_CONFIG);
1489 rsp.result = cpu_to_le16(L2CAP_CR_SUCCESS);
1490 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
1491 }
1492 } else {
1493 rsp.result = cpu_to_le16(L2CAP_CR_PEND);
1494 rsp.status = cpu_to_le16(L2CAP_CS_AUTHEN_PEND);
1495 }
1496
1497 l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_RSP,
1498 sizeof(rsp), &rsp);
1499
1500 if (test_bit(CONF_REQ_SENT, &chan->conf_state) ||
1501 rsp.result != L2CAP_CR_SUCCESS) {
1502 l2cap_chan_unlock(chan);
1503 continue;
1504 }
1505
1506 set_bit(CONF_REQ_SENT, &chan->conf_state);
1507 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
1508 l2cap_build_conf_req(chan, buf, sizeof(buf)), buf);
1509 chan->num_conf_req++;
1510 }
1511
1512 l2cap_chan_unlock(chan);
1513 }
1514
1515 mutex_unlock(&conn->chan_lock);
1516}
1517
1518static void l2cap_le_conn_ready(struct l2cap_conn *conn)
1519{
1520 struct hci_conn *hcon = conn->hcon;
1521 struct hci_dev *hdev = hcon->hdev;
1522
1523 BT_DBG("%s conn %p", hdev->name, conn);
1524
1525 /* For outgoing pairing which doesn't necessarily have an
1526 * associated socket (e.g. mgmt_pair_device).
1527 */
1528 if (hcon->out)
1529 smp_conn_security(hcon, hcon->pending_sec_level);
1530
1531 /* For LE slave connections, make sure the connection interval
1532 * is in the range of the minium and maximum interval that has
1533 * been configured for this connection. If not, then trigger
1534 * the connection update procedure.
1535 */
1536 if (hcon->role == HCI_ROLE_SLAVE &&
1537 (hcon->le_conn_interval < hcon->le_conn_min_interval ||
1538 hcon->le_conn_interval > hcon->le_conn_max_interval)) {
1539 struct l2cap_conn_param_update_req req;
1540
1541 req.min = cpu_to_le16(hcon->le_conn_min_interval);
1542 req.max = cpu_to_le16(hcon->le_conn_max_interval);
1543 req.latency = cpu_to_le16(hcon->le_conn_latency);
1544 req.to_multiplier = cpu_to_le16(hcon->le_supv_timeout);
1545
1546 l2cap_send_cmd(conn, l2cap_get_ident(conn),
1547 L2CAP_CONN_PARAM_UPDATE_REQ, sizeof(req), &req);
1548 }
1549}
1550
1551static void l2cap_conn_ready(struct l2cap_conn *conn)
1552{
1553 struct l2cap_chan *chan;
1554 struct hci_conn *hcon = conn->hcon;
1555
1556 BT_DBG("conn %p", conn);
1557
1558 if (hcon->type == ACL_LINK)
1559 l2cap_request_info(conn);
1560
1561 mutex_lock(&conn->chan_lock);
1562
1563 list_for_each_entry(chan, &conn->chan_l, list) {
1564
1565 l2cap_chan_lock(chan);
1566
1567 if (chan->scid == L2CAP_CID_A2MP) {
1568 l2cap_chan_unlock(chan);
1569 continue;
1570 }
1571
1572 if (hcon->type == LE_LINK) {
1573 l2cap_le_start(chan);
1574 } else if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) {
1575 if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE)
1576 l2cap_chan_ready(chan);
1577 } else if (chan->state == BT_CONNECT) {
1578 l2cap_do_start(chan);
1579 }
1580
1581 l2cap_chan_unlock(chan);
1582 }
1583
1584 mutex_unlock(&conn->chan_lock);
1585
1586 if (hcon->type == LE_LINK)
1587 l2cap_le_conn_ready(conn);
1588
1589 queue_work(hcon->hdev->workqueue, &conn->pending_rx_work);
1590}
1591
1592/* Notify sockets that we cannot guaranty reliability anymore */
1593static void l2cap_conn_unreliable(struct l2cap_conn *conn, int err)
1594{
1595 struct l2cap_chan *chan;
1596
1597 BT_DBG("conn %p", conn);
1598
1599 mutex_lock(&conn->chan_lock);
1600
1601 list_for_each_entry(chan, &conn->chan_l, list) {
1602 if (test_bit(FLAG_FORCE_RELIABLE, &chan->flags))
1603 l2cap_chan_set_err(chan, err);
1604 }
1605
1606 mutex_unlock(&conn->chan_lock);
1607}
1608
1609static void l2cap_info_timeout(struct work_struct *work)
1610{
1611 struct l2cap_conn *conn = container_of(work, struct l2cap_conn,
1612 info_timer.work);
1613
1614 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
1615 conn->info_ident = 0;
1616
1617 l2cap_conn_start(conn);
1618}
1619
1620/*
1621 * l2cap_user
1622 * External modules can register l2cap_user objects on l2cap_conn. The ->probe
1623 * callback is called during registration. The ->remove callback is called
1624 * during unregistration.
1625 * An l2cap_user object can either be explicitly unregistered or when the
1626 * underlying l2cap_conn object is deleted. This guarantees that l2cap->hcon,
1627 * l2cap->hchan, .. are valid as long as the remove callback hasn't been called.
1628 * External modules must own a reference to the l2cap_conn object if they intend
1629 * to call l2cap_unregister_user(). The l2cap_conn object might get destroyed at
1630 * any time if they don't.
1631 */
1632
1633int l2cap_register_user(struct l2cap_conn *conn, struct l2cap_user *user)
1634{
1635 struct hci_dev *hdev = conn->hcon->hdev;
1636 int ret;
1637
1638 /* We need to check whether l2cap_conn is registered. If it is not, we
1639 * must not register the l2cap_user. l2cap_conn_del() is unregisters
1640 * l2cap_conn objects, but doesn't provide its own locking. Instead, it
1641 * relies on the parent hci_conn object to be locked. This itself relies
1642 * on the hci_dev object to be locked. So we must lock the hci device
1643 * here, too. */
1644
1645 hci_dev_lock(hdev);
1646
1647 if (!list_empty(&user->list)) {
1648 ret = -EINVAL;
1649 goto out_unlock;
1650 }
1651
1652 /* conn->hchan is NULL after l2cap_conn_del() was called */
1653 if (!conn->hchan) {
1654 ret = -ENODEV;
1655 goto out_unlock;
1656 }
1657
1658 ret = user->probe(conn, user);
1659 if (ret)
1660 goto out_unlock;
1661
1662 list_add(&user->list, &conn->users);
1663 ret = 0;
1664
1665out_unlock:
1666 hci_dev_unlock(hdev);
1667 return ret;
1668}
1669EXPORT_SYMBOL(l2cap_register_user);
1670
1671void l2cap_unregister_user(struct l2cap_conn *conn, struct l2cap_user *user)
1672{
1673 struct hci_dev *hdev = conn->hcon->hdev;
1674
1675 hci_dev_lock(hdev);
1676
1677 if (list_empty(&user->list))
1678 goto out_unlock;
1679
1680 list_del_init(&user->list);
1681 user->remove(conn, user);
1682
1683out_unlock:
1684 hci_dev_unlock(hdev);
1685}
1686EXPORT_SYMBOL(l2cap_unregister_user);
1687
1688static void l2cap_unregister_all_users(struct l2cap_conn *conn)
1689{
1690 struct l2cap_user *user;
1691
1692 while (!list_empty(&conn->users)) {
1693 user = list_first_entry(&conn->users, struct l2cap_user, list);
1694 list_del_init(&user->list);
1695 user->remove(conn, user);
1696 }
1697}
1698
1699static void l2cap_conn_del(struct hci_conn *hcon, int err)
1700{
1701 struct l2cap_conn *conn = hcon->l2cap_data;
1702 struct l2cap_chan *chan, *l;
1703
1704 if (!conn)
1705 return;
1706
1707 BT_DBG("hcon %p conn %p, err %d", hcon, conn, err);
1708
1709 kfree_skb(conn->rx_skb);
1710
1711 skb_queue_purge(&conn->pending_rx);
1712
1713 /* We can not call flush_work(&conn->pending_rx_work) here since we
1714 * might block if we are running on a worker from the same workqueue
1715 * pending_rx_work is waiting on.
1716 */
1717 if (work_pending(&conn->pending_rx_work))
1718 cancel_work_sync(&conn->pending_rx_work);
1719
1720 if (work_pending(&conn->id_addr_update_work))
1721 cancel_work_sync(&conn->id_addr_update_work);
1722
1723 l2cap_unregister_all_users(conn);
1724
1725 /* Force the connection to be immediately dropped */
1726 hcon->disc_timeout = 0;
1727
1728 mutex_lock(&conn->chan_lock);
1729
1730 /* Kill channels */
1731 list_for_each_entry_safe(chan, l, &conn->chan_l, list) {
1732 l2cap_chan_hold(chan);
1733 l2cap_chan_lock(chan);
1734
1735 l2cap_chan_del(chan, err);
1736
1737 l2cap_chan_unlock(chan);
1738
1739 chan->ops->close(chan);
1740 l2cap_chan_put(chan);
1741 }
1742
1743 mutex_unlock(&conn->chan_lock);
1744
1745 hci_chan_del(conn->hchan);
1746
1747 if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT)
1748 cancel_delayed_work_sync(&conn->info_timer);
1749
1750 hcon->l2cap_data = NULL;
1751 conn->hchan = NULL;
1752 l2cap_conn_put(conn);
1753}
1754
1755static void l2cap_conn_free(struct kref *ref)
1756{
1757 struct l2cap_conn *conn = container_of(ref, struct l2cap_conn, ref);
1758
1759 hci_conn_put(conn->hcon);
1760 kfree(conn);
1761}
1762
1763struct l2cap_conn *l2cap_conn_get(struct l2cap_conn *conn)
1764{
1765 kref_get(&conn->ref);
1766 return conn;
1767}
1768EXPORT_SYMBOL(l2cap_conn_get);
1769
1770void l2cap_conn_put(struct l2cap_conn *conn)
1771{
1772 kref_put(&conn->ref, l2cap_conn_free);
1773}
1774EXPORT_SYMBOL(l2cap_conn_put);
1775
1776/* ---- Socket interface ---- */
1777
1778/* Find socket with psm and source / destination bdaddr.
1779 * Returns closest match.
1780 */
1781static struct l2cap_chan *l2cap_global_chan_by_psm(int state, __le16 psm,
1782 bdaddr_t *src,
1783 bdaddr_t *dst,
1784 u8 link_type)
1785{
1786 struct l2cap_chan *c, *c1 = NULL;
1787
1788 read_lock(&chan_list_lock);
1789
1790 list_for_each_entry(c, &chan_list, global_l) {
1791 if (state && c->state != state)
1792 continue;
1793
1794 if (link_type == ACL_LINK && c->src_type != BDADDR_BREDR)
1795 continue;
1796
1797 if (link_type == LE_LINK && c->src_type == BDADDR_BREDR)
1798 continue;
1799
1800 if (c->psm == psm) {
1801 int src_match, dst_match;
1802 int src_any, dst_any;
1803
1804 /* Exact match. */
1805 src_match = !bacmp(&c->src, src);
1806 dst_match = !bacmp(&c->dst, dst);
1807 if (src_match && dst_match) {
1808 l2cap_chan_hold(c);
1809 read_unlock(&chan_list_lock);
1810 return c;
1811 }
1812
1813 /* Closest match */
1814 src_any = !bacmp(&c->src, BDADDR_ANY);
1815 dst_any = !bacmp(&c->dst, BDADDR_ANY);
1816 if ((src_match && dst_any) || (src_any && dst_match) ||
1817 (src_any && dst_any))
1818 c1 = c;
1819 }
1820 }
1821
1822 if (c1)
1823 l2cap_chan_hold(c1);
1824
1825 read_unlock(&chan_list_lock);
1826
1827 return c1;
1828}
1829
1830static void l2cap_monitor_timeout(struct work_struct *work)
1831{
1832 struct l2cap_chan *chan = container_of(work, struct l2cap_chan,
1833 monitor_timer.work);
1834
1835 BT_DBG("chan %p", chan);
1836
1837 l2cap_chan_lock(chan);
1838
1839 if (!chan->conn) {
1840 l2cap_chan_unlock(chan);
1841 l2cap_chan_put(chan);
1842 return;
1843 }
1844
1845 l2cap_tx(chan, NULL, NULL, L2CAP_EV_MONITOR_TO);
1846
1847 l2cap_chan_unlock(chan);
1848 l2cap_chan_put(chan);
1849}
1850
1851static void l2cap_retrans_timeout(struct work_struct *work)
1852{
1853 struct l2cap_chan *chan = container_of(work, struct l2cap_chan,
1854 retrans_timer.work);
1855
1856 BT_DBG("chan %p", chan);
1857
1858 l2cap_chan_lock(chan);
1859
1860 if (!chan->conn) {
1861 l2cap_chan_unlock(chan);
1862 l2cap_chan_put(chan);
1863 return;
1864 }
1865
1866 l2cap_tx(chan, NULL, NULL, L2CAP_EV_RETRANS_TO);
1867 l2cap_chan_unlock(chan);
1868 l2cap_chan_put(chan);
1869}
1870
1871static void l2cap_streaming_send(struct l2cap_chan *chan,
1872 struct sk_buff_head *skbs)
1873{
1874 struct sk_buff *skb;
1875 struct l2cap_ctrl *control;
1876
1877 BT_DBG("chan %p, skbs %p", chan, skbs);
1878
1879 if (__chan_is_moving(chan))
1880 return;
1881
1882 skb_queue_splice_tail_init(skbs, &chan->tx_q);
1883
1884 while (!skb_queue_empty(&chan->tx_q)) {
1885
1886 skb = skb_dequeue(&chan->tx_q);
1887
1888 bt_cb(skb)->l2cap.retries = 1;
1889 control = &bt_cb(skb)->l2cap;
1890
1891 control->reqseq = 0;
1892 control->txseq = chan->next_tx_seq;
1893
1894 __pack_control(chan, control, skb);
1895
1896 if (chan->fcs == L2CAP_FCS_CRC16) {
1897 u16 fcs = crc16(0, (u8 *) skb->data, skb->len);
1898 put_unaligned_le16(fcs, skb_put(skb, L2CAP_FCS_SIZE));
1899 }
1900
1901 l2cap_do_send(chan, skb);
1902
1903 BT_DBG("Sent txseq %u", control->txseq);
1904
1905 chan->next_tx_seq = __next_seq(chan, chan->next_tx_seq);
1906 chan->frames_sent++;
1907 }
1908}
1909
1910static int l2cap_ertm_send(struct l2cap_chan *chan)
1911{
1912 struct sk_buff *skb, *tx_skb;
1913 struct l2cap_ctrl *control;
1914 int sent = 0;
1915
1916 BT_DBG("chan %p", chan);
1917
1918 if (chan->state != BT_CONNECTED)
1919 return -ENOTCONN;
1920
1921 if (test_bit(CONN_REMOTE_BUSY, &chan->conn_state))
1922 return 0;
1923
1924 if (__chan_is_moving(chan))
1925 return 0;
1926
1927 while (chan->tx_send_head &&
1928 chan->unacked_frames < chan->remote_tx_win &&
1929 chan->tx_state == L2CAP_TX_STATE_XMIT) {
1930
1931 skb = chan->tx_send_head;
1932
1933 bt_cb(skb)->l2cap.retries = 1;
1934 control = &bt_cb(skb)->l2cap;
1935
1936 if (test_and_clear_bit(CONN_SEND_FBIT, &chan->conn_state))
1937 control->final = 1;
1938
1939 control->reqseq = chan->buffer_seq;
1940 chan->last_acked_seq = chan->buffer_seq;
1941 control->txseq = chan->next_tx_seq;
1942
1943 __pack_control(chan, control, skb);
1944
1945 if (chan->fcs == L2CAP_FCS_CRC16) {
1946 u16 fcs = crc16(0, (u8 *) skb->data, skb->len);
1947 put_unaligned_le16(fcs, skb_put(skb, L2CAP_FCS_SIZE));
1948 }
1949
1950 /* Clone after data has been modified. Data is assumed to be
1951 read-only (for locking purposes) on cloned sk_buffs.
1952 */
1953 tx_skb = skb_clone(skb, GFP_KERNEL);
1954
1955 if (!tx_skb)
1956 break;
1957
1958 __set_retrans_timer(chan);
1959
1960 chan->next_tx_seq = __next_seq(chan, chan->next_tx_seq);
1961 chan->unacked_frames++;
1962 chan->frames_sent++;
1963 sent++;
1964
1965 if (skb_queue_is_last(&chan->tx_q, skb))
1966 chan->tx_send_head = NULL;
1967 else
1968 chan->tx_send_head = skb_queue_next(&chan->tx_q, skb);
1969
1970 l2cap_do_send(chan, tx_skb);
1971 BT_DBG("Sent txseq %u", control->txseq);
1972 }
1973
1974 BT_DBG("Sent %d, %u unacked, %u in ERTM queue", sent,
1975 chan->unacked_frames, skb_queue_len(&chan->tx_q));
1976
1977 return sent;
1978}
1979
1980static void l2cap_ertm_resend(struct l2cap_chan *chan)
1981{
1982 struct l2cap_ctrl control;
1983 struct sk_buff *skb;
1984 struct sk_buff *tx_skb;
1985 u16 seq;
1986
1987 BT_DBG("chan %p", chan);
1988
1989 if (test_bit(CONN_REMOTE_BUSY, &chan->conn_state))
1990 return;
1991
1992 if (__chan_is_moving(chan))
1993 return;
1994
1995 while (chan->retrans_list.head != L2CAP_SEQ_LIST_CLEAR) {
1996 seq = l2cap_seq_list_pop(&chan->retrans_list);
1997
1998 skb = l2cap_ertm_seq_in_queue(&chan->tx_q, seq);
1999 if (!skb) {
2000 BT_DBG("Error: Can't retransmit seq %d, frame missing",
2001 seq);
2002 continue;
2003 }
2004
2005 bt_cb(skb)->l2cap.retries++;
2006 control = bt_cb(skb)->l2cap;
2007
2008 if (chan->max_tx != 0 &&
2009 bt_cb(skb)->l2cap.retries > chan->max_tx) {
2010 BT_DBG("Retry limit exceeded (%d)", chan->max_tx);
2011 l2cap_send_disconn_req(chan, ECONNRESET);
2012 l2cap_seq_list_clear(&chan->retrans_list);
2013 break;
2014 }
2015
2016 control.reqseq = chan->buffer_seq;
2017 if (test_and_clear_bit(CONN_SEND_FBIT, &chan->conn_state))
2018 control.final = 1;
2019 else
2020 control.final = 0;
2021
2022 if (skb_cloned(skb)) {
2023 /* Cloned sk_buffs are read-only, so we need a
2024 * writeable copy
2025 */
2026 tx_skb = skb_copy(skb, GFP_KERNEL);
2027 } else {
2028 tx_skb = skb_clone(skb, GFP_KERNEL);
2029 }
2030
2031 if (!tx_skb) {
2032 l2cap_seq_list_clear(&chan->retrans_list);
2033 break;
2034 }
2035
2036 /* Update skb contents */
2037 if (test_bit(FLAG_EXT_CTRL, &chan->flags)) {
2038 put_unaligned_le32(__pack_extended_control(&control),
2039 tx_skb->data + L2CAP_HDR_SIZE);
2040 } else {
2041 put_unaligned_le16(__pack_enhanced_control(&control),
2042 tx_skb->data + L2CAP_HDR_SIZE);
2043 }
2044
2045 /* Update FCS */
2046 if (chan->fcs == L2CAP_FCS_CRC16) {
2047 u16 fcs = crc16(0, (u8 *) tx_skb->data,
2048 tx_skb->len - L2CAP_FCS_SIZE);
2049 put_unaligned_le16(fcs, skb_tail_pointer(tx_skb) -
2050 L2CAP_FCS_SIZE);
2051 }
2052
2053 l2cap_do_send(chan, tx_skb);
2054
2055 BT_DBG("Resent txseq %d", control.txseq);
2056
2057 chan->last_acked_seq = chan->buffer_seq;
2058 }
2059}
2060
2061static void l2cap_retransmit(struct l2cap_chan *chan,
2062 struct l2cap_ctrl *control)
2063{
2064 BT_DBG("chan %p, control %p", chan, control);
2065
2066 l2cap_seq_list_append(&chan->retrans_list, control->reqseq);
2067 l2cap_ertm_resend(chan);
2068}
2069
2070static void l2cap_retransmit_all(struct l2cap_chan *chan,
2071 struct l2cap_ctrl *control)
2072{
2073 struct sk_buff *skb;
2074
2075 BT_DBG("chan %p, control %p", chan, control);
2076
2077 if (control->poll)
2078 set_bit(CONN_SEND_FBIT, &chan->conn_state);
2079
2080 l2cap_seq_list_clear(&chan->retrans_list);
2081
2082 if (test_bit(CONN_REMOTE_BUSY, &chan->conn_state))
2083 return;
2084
2085 if (chan->unacked_frames) {
2086 skb_queue_walk(&chan->tx_q, skb) {
2087 if (bt_cb(skb)->l2cap.txseq == control->reqseq ||
2088 skb == chan->tx_send_head)
2089 break;
2090 }
2091
2092 skb_queue_walk_from(&chan->tx_q, skb) {
2093 if (skb == chan->tx_send_head)
2094 break;
2095
2096 l2cap_seq_list_append(&chan->retrans_list,
2097 bt_cb(skb)->l2cap.txseq);
2098 }
2099
2100 l2cap_ertm_resend(chan);
2101 }
2102}
2103
2104static void l2cap_send_ack(struct l2cap_chan *chan)
2105{
2106 struct l2cap_ctrl control;
2107 u16 frames_to_ack = __seq_offset(chan, chan->buffer_seq,
2108 chan->last_acked_seq);
2109 int threshold;
2110
2111 BT_DBG("chan %p last_acked_seq %d buffer_seq %d",
2112 chan, chan->last_acked_seq, chan->buffer_seq);
2113
2114 memset(&control, 0, sizeof(control));
2115 control.sframe = 1;
2116
2117 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state) &&
2118 chan->rx_state == L2CAP_RX_STATE_RECV) {
2119 __clear_ack_timer(chan);
2120 control.super = L2CAP_SUPER_RNR;
2121 control.reqseq = chan->buffer_seq;
2122 l2cap_send_sframe(chan, &control);
2123 } else {
2124 if (!test_bit(CONN_REMOTE_BUSY, &chan->conn_state)) {
2125 l2cap_ertm_send(chan);
2126 /* If any i-frames were sent, they included an ack */
2127 if (chan->buffer_seq == chan->last_acked_seq)
2128 frames_to_ack = 0;
2129 }
2130
2131 /* Ack now if the window is 3/4ths full.
2132 * Calculate without mul or div
2133 */
2134 threshold = chan->ack_win;
2135 threshold += threshold << 1;
2136 threshold >>= 2;
2137
2138 BT_DBG("frames_to_ack %u, threshold %d", frames_to_ack,
2139 threshold);
2140
2141 if (frames_to_ack >= threshold) {
2142 __clear_ack_timer(chan);
2143 control.super = L2CAP_SUPER_RR;
2144 control.reqseq = chan->buffer_seq;
2145 l2cap_send_sframe(chan, &control);
2146 frames_to_ack = 0;
2147 }
2148
2149 if (frames_to_ack)
2150 __set_ack_timer(chan);
2151 }
2152}
2153
2154static inline int l2cap_skbuff_fromiovec(struct l2cap_chan *chan,
2155 struct msghdr *msg, int len,
2156 int count, struct sk_buff *skb)
2157{
2158 struct l2cap_conn *conn = chan->conn;
2159 struct sk_buff **frag;
2160 int sent = 0;
2161
2162 if (!copy_from_iter_full(skb_put(skb, count), count, &msg->msg_iter))
2163 return -EFAULT;
2164
2165 sent += count;
2166 len -= count;
2167
2168 /* Continuation fragments (no L2CAP header) */
2169 frag = &skb_shinfo(skb)->frag_list;
2170 while (len) {
2171 struct sk_buff *tmp;
2172
2173 count = min_t(unsigned int, conn->mtu, len);
2174
2175 tmp = chan->ops->alloc_skb(chan, 0, count,
2176 msg->msg_flags & MSG_DONTWAIT);
2177 if (IS_ERR(tmp))
2178 return PTR_ERR(tmp);
2179
2180 *frag = tmp;
2181
2182 if (!copy_from_iter_full(skb_put(*frag, count), count,
2183 &msg->msg_iter))
2184 return -EFAULT;
2185
2186 sent += count;
2187 len -= count;
2188
2189 skb->len += (*frag)->len;
2190 skb->data_len += (*frag)->len;
2191
2192 frag = &(*frag)->next;
2193 }
2194
2195 return sent;
2196}
2197
2198static struct sk_buff *l2cap_create_connless_pdu(struct l2cap_chan *chan,
2199 struct msghdr *msg, size_t len)
2200{
2201 struct l2cap_conn *conn = chan->conn;
2202 struct sk_buff *skb;
2203 int err, count, hlen = L2CAP_HDR_SIZE + L2CAP_PSMLEN_SIZE;
2204 struct l2cap_hdr *lh;
2205
2206 BT_DBG("chan %p psm 0x%2.2x len %zu", chan,
2207 __le16_to_cpu(chan->psm), len);
2208
2209 count = min_t(unsigned int, (conn->mtu - hlen), len);
2210
2211 skb = chan->ops->alloc_skb(chan, hlen, count,
2212 msg->msg_flags & MSG_DONTWAIT);
2213 if (IS_ERR(skb))
2214 return skb;
2215
2216 /* Create L2CAP header */
2217 lh = skb_put(skb, L2CAP_HDR_SIZE);
2218 lh->cid = cpu_to_le16(chan->dcid);
2219 lh->len = cpu_to_le16(len + L2CAP_PSMLEN_SIZE);
2220 put_unaligned(chan->psm, (__le16 *) skb_put(skb, L2CAP_PSMLEN_SIZE));
2221
2222 err = l2cap_skbuff_fromiovec(chan, msg, len, count, skb);
2223 if (unlikely(err < 0)) {
2224 kfree_skb(skb);
2225 return ERR_PTR(err);
2226 }
2227 return skb;
2228}
2229
2230static struct sk_buff *l2cap_create_basic_pdu(struct l2cap_chan *chan,
2231 struct msghdr *msg, size_t len)
2232{
2233 struct l2cap_conn *conn = chan->conn;
2234 struct sk_buff *skb;
2235 int err, count;
2236 struct l2cap_hdr *lh;
2237
2238 BT_DBG("chan %p len %zu", chan, len);
2239
2240 count = min_t(unsigned int, (conn->mtu - L2CAP_HDR_SIZE), len);
2241
2242 skb = chan->ops->alloc_skb(chan, L2CAP_HDR_SIZE, count,
2243 msg->msg_flags & MSG_DONTWAIT);
2244 if (IS_ERR(skb))
2245 return skb;
2246
2247 /* Create L2CAP header */
2248 lh = skb_put(skb, L2CAP_HDR_SIZE);
2249 lh->cid = cpu_to_le16(chan->dcid);
2250 lh->len = cpu_to_le16(len);
2251
2252 err = l2cap_skbuff_fromiovec(chan, msg, len, count, skb);
2253 if (unlikely(err < 0)) {
2254 kfree_skb(skb);
2255 return ERR_PTR(err);
2256 }
2257 return skb;
2258}
2259
2260static struct sk_buff *l2cap_create_iframe_pdu(struct l2cap_chan *chan,
2261 struct msghdr *msg, size_t len,
2262 u16 sdulen)
2263{
2264 struct l2cap_conn *conn = chan->conn;
2265 struct sk_buff *skb;
2266 int err, count, hlen;
2267 struct l2cap_hdr *lh;
2268
2269 BT_DBG("chan %p len %zu", chan, len);
2270
2271 if (!conn)
2272 return ERR_PTR(-ENOTCONN);
2273
2274 hlen = __ertm_hdr_size(chan);
2275
2276 if (sdulen)
2277 hlen += L2CAP_SDULEN_SIZE;
2278
2279 if (chan->fcs == L2CAP_FCS_CRC16)
2280 hlen += L2CAP_FCS_SIZE;
2281
2282 count = min_t(unsigned int, (conn->mtu - hlen), len);
2283
2284 skb = chan->ops->alloc_skb(chan, hlen, count,
2285 msg->msg_flags & MSG_DONTWAIT);
2286 if (IS_ERR(skb))
2287 return skb;
2288
2289 /* Create L2CAP header */
2290 lh = skb_put(skb, L2CAP_HDR_SIZE);
2291 lh->cid = cpu_to_le16(chan->dcid);
2292 lh->len = cpu_to_le16(len + (hlen - L2CAP_HDR_SIZE));
2293
2294 /* Control header is populated later */
2295 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
2296 put_unaligned_le32(0, skb_put(skb, L2CAP_EXT_CTRL_SIZE));
2297 else
2298 put_unaligned_le16(0, skb_put(skb, L2CAP_ENH_CTRL_SIZE));
2299
2300 if (sdulen)
2301 put_unaligned_le16(sdulen, skb_put(skb, L2CAP_SDULEN_SIZE));
2302
2303 err = l2cap_skbuff_fromiovec(chan, msg, len, count, skb);
2304 if (unlikely(err < 0)) {
2305 kfree_skb(skb);
2306 return ERR_PTR(err);
2307 }
2308
2309 bt_cb(skb)->l2cap.fcs = chan->fcs;
2310 bt_cb(skb)->l2cap.retries = 0;
2311 return skb;
2312}
2313
2314static int l2cap_segment_sdu(struct l2cap_chan *chan,
2315 struct sk_buff_head *seg_queue,
2316 struct msghdr *msg, size_t len)
2317{
2318 struct sk_buff *skb;
2319 u16 sdu_len;
2320 size_t pdu_len;
2321 u8 sar;
2322
2323 BT_DBG("chan %p, msg %p, len %zu", chan, msg, len);
2324
2325 /* It is critical that ERTM PDUs fit in a single HCI fragment,
2326 * so fragmented skbs are not used. The HCI layer's handling
2327 * of fragmented skbs is not compatible with ERTM's queueing.
2328 */
2329
2330 /* PDU size is derived from the HCI MTU */
2331 pdu_len = chan->conn->mtu;
2332
2333 /* Constrain PDU size for BR/EDR connections */
2334 if (!chan->hs_hcon)
2335 pdu_len = min_t(size_t, pdu_len, L2CAP_BREDR_MAX_PAYLOAD);
2336
2337 /* Adjust for largest possible L2CAP overhead. */
2338 if (chan->fcs)
2339 pdu_len -= L2CAP_FCS_SIZE;
2340
2341 pdu_len -= __ertm_hdr_size(chan);
2342
2343 /* Remote device may have requested smaller PDUs */
2344 pdu_len = min_t(size_t, pdu_len, chan->remote_mps);
2345
2346 if (len <= pdu_len) {
2347 sar = L2CAP_SAR_UNSEGMENTED;
2348 sdu_len = 0;
2349 pdu_len = len;
2350 } else {
2351 sar = L2CAP_SAR_START;
2352 sdu_len = len;
2353 }
2354
2355 while (len > 0) {
2356 skb = l2cap_create_iframe_pdu(chan, msg, pdu_len, sdu_len);
2357
2358 if (IS_ERR(skb)) {
2359 __skb_queue_purge(seg_queue);
2360 return PTR_ERR(skb);
2361 }
2362
2363 bt_cb(skb)->l2cap.sar = sar;
2364 __skb_queue_tail(seg_queue, skb);
2365
2366 len -= pdu_len;
2367 if (sdu_len)
2368 sdu_len = 0;
2369
2370 if (len <= pdu_len) {
2371 sar = L2CAP_SAR_END;
2372 pdu_len = len;
2373 } else {
2374 sar = L2CAP_SAR_CONTINUE;
2375 }
2376 }
2377
2378 return 0;
2379}
2380
2381static struct sk_buff *l2cap_create_le_flowctl_pdu(struct l2cap_chan *chan,
2382 struct msghdr *msg,
2383 size_t len, u16 sdulen)
2384{
2385 struct l2cap_conn *conn = chan->conn;
2386 struct sk_buff *skb;
2387 int err, count, hlen;
2388 struct l2cap_hdr *lh;
2389
2390 BT_DBG("chan %p len %zu", chan, len);
2391
2392 if (!conn)
2393 return ERR_PTR(-ENOTCONN);
2394
2395 hlen = L2CAP_HDR_SIZE;
2396
2397 if (sdulen)
2398 hlen += L2CAP_SDULEN_SIZE;
2399
2400 count = min_t(unsigned int, (conn->mtu - hlen), len);
2401
2402 skb = chan->ops->alloc_skb(chan, hlen, count,
2403 msg->msg_flags & MSG_DONTWAIT);
2404 if (IS_ERR(skb))
2405 return skb;
2406
2407 /* Create L2CAP header */
2408 lh = skb_put(skb, L2CAP_HDR_SIZE);
2409 lh->cid = cpu_to_le16(chan->dcid);
2410 lh->len = cpu_to_le16(len + (hlen - L2CAP_HDR_SIZE));
2411
2412 if (sdulen)
2413 put_unaligned_le16(sdulen, skb_put(skb, L2CAP_SDULEN_SIZE));
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
2421 return skb;
2422}
2423
2424static int l2cap_segment_le_sdu(struct l2cap_chan *chan,
2425 struct sk_buff_head *seg_queue,
2426 struct msghdr *msg, size_t len)
2427{
2428 struct sk_buff *skb;
2429 size_t pdu_len;
2430 u16 sdu_len;
2431
2432 BT_DBG("chan %p, msg %p, len %zu", chan, msg, len);
2433
2434 sdu_len = len;
2435 pdu_len = chan->remote_mps - L2CAP_SDULEN_SIZE;
2436
2437 while (len > 0) {
2438 if (len <= pdu_len)
2439 pdu_len = len;
2440
2441 skb = l2cap_create_le_flowctl_pdu(chan, msg, pdu_len, sdu_len);
2442 if (IS_ERR(skb)) {
2443 __skb_queue_purge(seg_queue);
2444 return PTR_ERR(skb);
2445 }
2446
2447 __skb_queue_tail(seg_queue, skb);
2448
2449 len -= pdu_len;
2450
2451 if (sdu_len) {
2452 sdu_len = 0;
2453 pdu_len += L2CAP_SDULEN_SIZE;
2454 }
2455 }
2456
2457 return 0;
2458}
2459
2460static void l2cap_le_flowctl_send(struct l2cap_chan *chan)
2461{
2462 int sent = 0;
2463
2464 BT_DBG("chan %p", chan);
2465
2466 while (chan->tx_credits && !skb_queue_empty(&chan->tx_q)) {
2467 l2cap_do_send(chan, skb_dequeue(&chan->tx_q));
2468 chan->tx_credits--;
2469 sent++;
2470 }
2471
2472 BT_DBG("Sent %d credits %u queued %u", sent, chan->tx_credits,
2473 skb_queue_len(&chan->tx_q));
2474}
2475
2476int l2cap_chan_send(struct l2cap_chan *chan, struct msghdr *msg, size_t len)
2477{
2478 struct sk_buff *skb;
2479 int err;
2480 struct sk_buff_head seg_queue;
2481
2482 if (!chan->conn)
2483 return -ENOTCONN;
2484
2485 /* Connectionless channel */
2486 if (chan->chan_type == L2CAP_CHAN_CONN_LESS) {
2487 skb = l2cap_create_connless_pdu(chan, msg, len);
2488 if (IS_ERR(skb))
2489 return PTR_ERR(skb);
2490
2491 /* Channel lock is released before requesting new skb and then
2492 * reacquired thus we need to recheck channel state.
2493 */
2494 if (chan->state != BT_CONNECTED) {
2495 kfree_skb(skb);
2496 return -ENOTCONN;
2497 }
2498
2499 l2cap_do_send(chan, skb);
2500 return len;
2501 }
2502
2503 switch (chan->mode) {
2504 case L2CAP_MODE_LE_FLOWCTL:
2505 /* Check outgoing MTU */
2506 if (len > chan->omtu)
2507 return -EMSGSIZE;
2508
2509 __skb_queue_head_init(&seg_queue);
2510
2511 err = l2cap_segment_le_sdu(chan, &seg_queue, msg, len);
2512
2513 if (chan->state != BT_CONNECTED) {
2514 __skb_queue_purge(&seg_queue);
2515 err = -ENOTCONN;
2516 }
2517
2518 if (err)
2519 return err;
2520
2521 skb_queue_splice_tail_init(&seg_queue, &chan->tx_q);
2522
2523 l2cap_le_flowctl_send(chan);
2524
2525 if (!chan->tx_credits)
2526 chan->ops->suspend(chan);
2527
2528 err = len;
2529
2530 break;
2531
2532 case L2CAP_MODE_BASIC:
2533 /* Check outgoing MTU */
2534 if (len > chan->omtu)
2535 return -EMSGSIZE;
2536
2537 /* Create a basic PDU */
2538 skb = l2cap_create_basic_pdu(chan, msg, len);
2539 if (IS_ERR(skb))
2540 return PTR_ERR(skb);
2541
2542 /* Channel lock is released before requesting new skb and then
2543 * reacquired thus we need to recheck channel state.
2544 */
2545 if (chan->state != BT_CONNECTED) {
2546 kfree_skb(skb);
2547 return -ENOTCONN;
2548 }
2549
2550 l2cap_do_send(chan, skb);
2551 err = len;
2552 break;
2553
2554 case L2CAP_MODE_ERTM:
2555 case L2CAP_MODE_STREAMING:
2556 /* Check outgoing MTU */
2557 if (len > chan->omtu) {
2558 err = -EMSGSIZE;
2559 break;
2560 }
2561
2562 __skb_queue_head_init(&seg_queue);
2563
2564 /* Do segmentation before calling in to the state machine,
2565 * since it's possible to block while waiting for memory
2566 * allocation.
2567 */
2568 err = l2cap_segment_sdu(chan, &seg_queue, msg, len);
2569
2570 /* The channel could have been closed while segmenting,
2571 * check that it is still connected.
2572 */
2573 if (chan->state != BT_CONNECTED) {
2574 __skb_queue_purge(&seg_queue);
2575 err = -ENOTCONN;
2576 }
2577
2578 if (err)
2579 break;
2580
2581 if (chan->mode == L2CAP_MODE_ERTM)
2582 l2cap_tx(chan, NULL, &seg_queue, L2CAP_EV_DATA_REQUEST);
2583 else
2584 l2cap_streaming_send(chan, &seg_queue);
2585
2586 err = len;
2587
2588 /* If the skbs were not queued for sending, they'll still be in
2589 * seg_queue and need to be purged.
2590 */
2591 __skb_queue_purge(&seg_queue);
2592 break;
2593
2594 default:
2595 BT_DBG("bad state %1.1x", chan->mode);
2596 err = -EBADFD;
2597 }
2598
2599 return err;
2600}
2601EXPORT_SYMBOL_GPL(l2cap_chan_send);
2602
2603static void l2cap_send_srej(struct l2cap_chan *chan, u16 txseq)
2604{
2605 struct l2cap_ctrl control;
2606 u16 seq;
2607
2608 BT_DBG("chan %p, txseq %u", chan, txseq);
2609
2610 memset(&control, 0, sizeof(control));
2611 control.sframe = 1;
2612 control.super = L2CAP_SUPER_SREJ;
2613
2614 for (seq = chan->expected_tx_seq; seq != txseq;
2615 seq = __next_seq(chan, seq)) {
2616 if (!l2cap_ertm_seq_in_queue(&chan->srej_q, seq)) {
2617 control.reqseq = seq;
2618 l2cap_send_sframe(chan, &control);
2619 l2cap_seq_list_append(&chan->srej_list, seq);
2620 }
2621 }
2622
2623 chan->expected_tx_seq = __next_seq(chan, txseq);
2624}
2625
2626static void l2cap_send_srej_tail(struct l2cap_chan *chan)
2627{
2628 struct l2cap_ctrl control;
2629
2630 BT_DBG("chan %p", chan);
2631
2632 if (chan->srej_list.tail == L2CAP_SEQ_LIST_CLEAR)
2633 return;
2634
2635 memset(&control, 0, sizeof(control));
2636 control.sframe = 1;
2637 control.super = L2CAP_SUPER_SREJ;
2638 control.reqseq = chan->srej_list.tail;
2639 l2cap_send_sframe(chan, &control);
2640}
2641
2642static void l2cap_send_srej_list(struct l2cap_chan *chan, u16 txseq)
2643{
2644 struct l2cap_ctrl control;
2645 u16 initial_head;
2646 u16 seq;
2647
2648 BT_DBG("chan %p, txseq %u", chan, txseq);
2649
2650 memset(&control, 0, sizeof(control));
2651 control.sframe = 1;
2652 control.super = L2CAP_SUPER_SREJ;
2653
2654 /* Capture initial list head to allow only one pass through the list. */
2655 initial_head = chan->srej_list.head;
2656
2657 do {
2658 seq = l2cap_seq_list_pop(&chan->srej_list);
2659 if (seq == txseq || seq == L2CAP_SEQ_LIST_CLEAR)
2660 break;
2661
2662 control.reqseq = seq;
2663 l2cap_send_sframe(chan, &control);
2664 l2cap_seq_list_append(&chan->srej_list, seq);
2665 } while (chan->srej_list.head != initial_head);
2666}
2667
2668static void l2cap_process_reqseq(struct l2cap_chan *chan, u16 reqseq)
2669{
2670 struct sk_buff *acked_skb;
2671 u16 ackseq;
2672
2673 BT_DBG("chan %p, reqseq %u", chan, reqseq);
2674
2675 if (chan->unacked_frames == 0 || reqseq == chan->expected_ack_seq)
2676 return;
2677
2678 BT_DBG("expected_ack_seq %u, unacked_frames %u",
2679 chan->expected_ack_seq, chan->unacked_frames);
2680
2681 for (ackseq = chan->expected_ack_seq; ackseq != reqseq;
2682 ackseq = __next_seq(chan, ackseq)) {
2683
2684 acked_skb = l2cap_ertm_seq_in_queue(&chan->tx_q, ackseq);
2685 if (acked_skb) {
2686 skb_unlink(acked_skb, &chan->tx_q);
2687 kfree_skb(acked_skb);
2688 chan->unacked_frames--;
2689 }
2690 }
2691
2692 chan->expected_ack_seq = reqseq;
2693
2694 if (chan->unacked_frames == 0)
2695 __clear_retrans_timer(chan);
2696
2697 BT_DBG("unacked_frames %u", chan->unacked_frames);
2698}
2699
2700static void l2cap_abort_rx_srej_sent(struct l2cap_chan *chan)
2701{
2702 BT_DBG("chan %p", chan);
2703
2704 chan->expected_tx_seq = chan->buffer_seq;
2705 l2cap_seq_list_clear(&chan->srej_list);
2706 skb_queue_purge(&chan->srej_q);
2707 chan->rx_state = L2CAP_RX_STATE_RECV;
2708}
2709
2710static void l2cap_tx_state_xmit(struct l2cap_chan *chan,
2711 struct l2cap_ctrl *control,
2712 struct sk_buff_head *skbs, u8 event)
2713{
2714 BT_DBG("chan %p, control %p, skbs %p, event %d", chan, control, skbs,
2715 event);
2716
2717 switch (event) {
2718 case L2CAP_EV_DATA_REQUEST:
2719 if (chan->tx_send_head == NULL)
2720 chan->tx_send_head = skb_peek(skbs);
2721
2722 skb_queue_splice_tail_init(skbs, &chan->tx_q);
2723 l2cap_ertm_send(chan);
2724 break;
2725 case L2CAP_EV_LOCAL_BUSY_DETECTED:
2726 BT_DBG("Enter LOCAL_BUSY");
2727 set_bit(CONN_LOCAL_BUSY, &chan->conn_state);
2728
2729 if (chan->rx_state == L2CAP_RX_STATE_SREJ_SENT) {
2730 /* The SREJ_SENT state must be aborted if we are to
2731 * enter the LOCAL_BUSY state.
2732 */
2733 l2cap_abort_rx_srej_sent(chan);
2734 }
2735
2736 l2cap_send_ack(chan);
2737
2738 break;
2739 case L2CAP_EV_LOCAL_BUSY_CLEAR:
2740 BT_DBG("Exit LOCAL_BUSY");
2741 clear_bit(CONN_LOCAL_BUSY, &chan->conn_state);
2742
2743 if (test_bit(CONN_RNR_SENT, &chan->conn_state)) {
2744 struct l2cap_ctrl local_control;
2745
2746 memset(&local_control, 0, sizeof(local_control));
2747 local_control.sframe = 1;
2748 local_control.super = L2CAP_SUPER_RR;
2749 local_control.poll = 1;
2750 local_control.reqseq = chan->buffer_seq;
2751 l2cap_send_sframe(chan, &local_control);
2752
2753 chan->retry_count = 1;
2754 __set_monitor_timer(chan);
2755 chan->tx_state = L2CAP_TX_STATE_WAIT_F;
2756 }
2757 break;
2758 case L2CAP_EV_RECV_REQSEQ_AND_FBIT:
2759 l2cap_process_reqseq(chan, control->reqseq);
2760 break;
2761 case L2CAP_EV_EXPLICIT_POLL:
2762 l2cap_send_rr_or_rnr(chan, 1);
2763 chan->retry_count = 1;
2764 __set_monitor_timer(chan);
2765 __clear_ack_timer(chan);
2766 chan->tx_state = L2CAP_TX_STATE_WAIT_F;
2767 break;
2768 case L2CAP_EV_RETRANS_TO:
2769 l2cap_send_rr_or_rnr(chan, 1);
2770 chan->retry_count = 1;
2771 __set_monitor_timer(chan);
2772 chan->tx_state = L2CAP_TX_STATE_WAIT_F;
2773 break;
2774 case L2CAP_EV_RECV_FBIT:
2775 /* Nothing to process */
2776 break;
2777 default:
2778 break;
2779 }
2780}
2781
2782static void l2cap_tx_state_wait_f(struct l2cap_chan *chan,
2783 struct l2cap_ctrl *control,
2784 struct sk_buff_head *skbs, u8 event)
2785{
2786 BT_DBG("chan %p, control %p, skbs %p, event %d", chan, control, skbs,
2787 event);
2788
2789 switch (event) {
2790 case L2CAP_EV_DATA_REQUEST:
2791 if (chan->tx_send_head == NULL)
2792 chan->tx_send_head = skb_peek(skbs);
2793 /* Queue data, but don't send. */
2794 skb_queue_splice_tail_init(skbs, &chan->tx_q);
2795 break;
2796 case L2CAP_EV_LOCAL_BUSY_DETECTED:
2797 BT_DBG("Enter LOCAL_BUSY");
2798 set_bit(CONN_LOCAL_BUSY, &chan->conn_state);
2799
2800 if (chan->rx_state == L2CAP_RX_STATE_SREJ_SENT) {
2801 /* The SREJ_SENT state must be aborted if we are to
2802 * enter the LOCAL_BUSY state.
2803 */
2804 l2cap_abort_rx_srej_sent(chan);
2805 }
2806
2807 l2cap_send_ack(chan);
2808
2809 break;
2810 case L2CAP_EV_LOCAL_BUSY_CLEAR:
2811 BT_DBG("Exit LOCAL_BUSY");
2812 clear_bit(CONN_LOCAL_BUSY, &chan->conn_state);
2813
2814 if (test_bit(CONN_RNR_SENT, &chan->conn_state)) {
2815 struct l2cap_ctrl local_control;
2816 memset(&local_control, 0, sizeof(local_control));
2817 local_control.sframe = 1;
2818 local_control.super = L2CAP_SUPER_RR;
2819 local_control.poll = 1;
2820 local_control.reqseq = chan->buffer_seq;
2821 l2cap_send_sframe(chan, &local_control);
2822
2823 chan->retry_count = 1;
2824 __set_monitor_timer(chan);
2825 chan->tx_state = L2CAP_TX_STATE_WAIT_F;
2826 }
2827 break;
2828 case L2CAP_EV_RECV_REQSEQ_AND_FBIT:
2829 l2cap_process_reqseq(chan, control->reqseq);
2830
2831 /* Fall through */
2832
2833 case L2CAP_EV_RECV_FBIT:
2834 if (control && control->final) {
2835 __clear_monitor_timer(chan);
2836 if (chan->unacked_frames > 0)
2837 __set_retrans_timer(chan);
2838 chan->retry_count = 0;
2839 chan->tx_state = L2CAP_TX_STATE_XMIT;
2840 BT_DBG("recv fbit tx_state 0x2.2%x", chan->tx_state);
2841 }
2842 break;
2843 case L2CAP_EV_EXPLICIT_POLL:
2844 /* Ignore */
2845 break;
2846 case L2CAP_EV_MONITOR_TO:
2847 if (chan->max_tx == 0 || chan->retry_count < chan->max_tx) {
2848 l2cap_send_rr_or_rnr(chan, 1);
2849 __set_monitor_timer(chan);
2850 chan->retry_count++;
2851 } else {
2852 l2cap_send_disconn_req(chan, ECONNABORTED);
2853 }
2854 break;
2855 default:
2856 break;
2857 }
2858}
2859
2860static void l2cap_tx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
2861 struct sk_buff_head *skbs, u8 event)
2862{
2863 BT_DBG("chan %p, control %p, skbs %p, event %d, state %d",
2864 chan, control, skbs, event, chan->tx_state);
2865
2866 switch (chan->tx_state) {
2867 case L2CAP_TX_STATE_XMIT:
2868 l2cap_tx_state_xmit(chan, control, skbs, event);
2869 break;
2870 case L2CAP_TX_STATE_WAIT_F:
2871 l2cap_tx_state_wait_f(chan, control, skbs, event);
2872 break;
2873 default:
2874 /* Ignore event */
2875 break;
2876 }
2877}
2878
2879static void l2cap_pass_to_tx(struct l2cap_chan *chan,
2880 struct l2cap_ctrl *control)
2881{
2882 BT_DBG("chan %p, control %p", chan, control);
2883 l2cap_tx(chan, control, NULL, L2CAP_EV_RECV_REQSEQ_AND_FBIT);
2884}
2885
2886static void l2cap_pass_to_tx_fbit(struct l2cap_chan *chan,
2887 struct l2cap_ctrl *control)
2888{
2889 BT_DBG("chan %p, control %p", chan, control);
2890 l2cap_tx(chan, control, NULL, L2CAP_EV_RECV_FBIT);
2891}
2892
2893/* Copy frame to all raw sockets on that connection */
2894static void l2cap_raw_recv(struct l2cap_conn *conn, struct sk_buff *skb)
2895{
2896 struct sk_buff *nskb;
2897 struct l2cap_chan *chan;
2898
2899 BT_DBG("conn %p", conn);
2900
2901 mutex_lock(&conn->chan_lock);
2902
2903 list_for_each_entry(chan, &conn->chan_l, list) {
2904 if (chan->chan_type != L2CAP_CHAN_RAW)
2905 continue;
2906
2907 /* Don't send frame to the channel it came from */
2908 if (bt_cb(skb)->l2cap.chan == chan)
2909 continue;
2910
2911 nskb = skb_clone(skb, GFP_KERNEL);
2912 if (!nskb)
2913 continue;
2914 if (chan->ops->recv(chan, nskb))
2915 kfree_skb(nskb);
2916 }
2917
2918 mutex_unlock(&conn->chan_lock);
2919}
2920
2921/* ---- L2CAP signalling commands ---- */
2922static struct sk_buff *l2cap_build_cmd(struct l2cap_conn *conn, u8 code,
2923 u8 ident, u16 dlen, void *data)
2924{
2925 struct sk_buff *skb, **frag;
2926 struct l2cap_cmd_hdr *cmd;
2927 struct l2cap_hdr *lh;
2928 int len, count;
2929
2930 BT_DBG("conn %p, code 0x%2.2x, ident 0x%2.2x, len %u",
2931 conn, code, ident, dlen);
2932
2933 if (conn->mtu < L2CAP_HDR_SIZE + L2CAP_CMD_HDR_SIZE)
2934 return NULL;
2935
2936 len = L2CAP_HDR_SIZE + L2CAP_CMD_HDR_SIZE + dlen;
2937 count = min_t(unsigned int, conn->mtu, len);
2938
2939 skb = bt_skb_alloc(count, GFP_KERNEL);
2940 if (!skb)
2941 return NULL;
2942
2943 lh = skb_put(skb, L2CAP_HDR_SIZE);
2944 lh->len = cpu_to_le16(L2CAP_CMD_HDR_SIZE + dlen);
2945
2946 if (conn->hcon->type == LE_LINK)
2947 lh->cid = cpu_to_le16(L2CAP_CID_LE_SIGNALING);
2948 else
2949 lh->cid = cpu_to_le16(L2CAP_CID_SIGNALING);
2950
2951 cmd = skb_put(skb, L2CAP_CMD_HDR_SIZE);
2952 cmd->code = code;
2953 cmd->ident = ident;
2954 cmd->len = cpu_to_le16(dlen);
2955
2956 if (dlen) {
2957 count -= L2CAP_HDR_SIZE + L2CAP_CMD_HDR_SIZE;
2958 skb_put_data(skb, data, count);
2959 data += count;
2960 }
2961
2962 len -= skb->len;
2963
2964 /* Continuation fragments (no L2CAP header) */
2965 frag = &skb_shinfo(skb)->frag_list;
2966 while (len) {
2967 count = min_t(unsigned int, conn->mtu, len);
2968
2969 *frag = bt_skb_alloc(count, GFP_KERNEL);
2970 if (!*frag)
2971 goto fail;
2972
2973 skb_put_data(*frag, data, count);
2974
2975 len -= count;
2976 data += count;
2977
2978 frag = &(*frag)->next;
2979 }
2980
2981 return skb;
2982
2983fail:
2984 kfree_skb(skb);
2985 return NULL;
2986}
2987
2988static inline int l2cap_get_conf_opt(void **ptr, int *type, int *olen,
2989 unsigned long *val)
2990{
2991 struct l2cap_conf_opt *opt = *ptr;
2992 int len;
2993
2994 len = L2CAP_CONF_OPT_SIZE + opt->len;
2995 *ptr += len;
2996
2997 *type = opt->type;
2998 *olen = opt->len;
2999
3000 switch (opt->len) {
3001 case 1:
3002 *val = *((u8 *) opt->val);
3003 break;
3004
3005 case 2:
3006 *val = get_unaligned_le16(opt->val);
3007 break;
3008
3009 case 4:
3010 *val = get_unaligned_le32(opt->val);
3011 break;
3012
3013 default:
3014 *val = (unsigned long) opt->val;
3015 break;
3016 }
3017
3018 BT_DBG("type 0x%2.2x len %u val 0x%lx", *type, opt->len, *val);
3019 return len;
3020}
3021
3022static void l2cap_add_conf_opt(void **ptr, u8 type, u8 len, unsigned long val, size_t size)
3023{
3024 struct l2cap_conf_opt *opt = *ptr;
3025
3026 BT_DBG("type 0x%2.2x len %u val 0x%lx", type, len, val);
3027
3028 if (size < L2CAP_CONF_OPT_SIZE + len)
3029 return;
3030
3031 opt->type = type;
3032 opt->len = len;
3033
3034 switch (len) {
3035 case 1:
3036 *((u8 *) opt->val) = val;
3037 break;
3038
3039 case 2:
3040 put_unaligned_le16(val, opt->val);
3041 break;
3042
3043 case 4:
3044 put_unaligned_le32(val, opt->val);
3045 break;
3046
3047 default:
3048 memcpy(opt->val, (void *) val, len);
3049 break;
3050 }
3051
3052 *ptr += L2CAP_CONF_OPT_SIZE + len;
3053}
3054
3055static void l2cap_add_opt_efs(void **ptr, struct l2cap_chan *chan, size_t size)
3056{
3057 struct l2cap_conf_efs efs;
3058
3059 switch (chan->mode) {
3060 case L2CAP_MODE_ERTM:
3061 efs.id = chan->local_id;
3062 efs.stype = chan->local_stype;
3063 efs.msdu = cpu_to_le16(chan->local_msdu);
3064 efs.sdu_itime = cpu_to_le32(chan->local_sdu_itime);
3065 efs.acc_lat = cpu_to_le32(L2CAP_DEFAULT_ACC_LAT);
3066 efs.flush_to = cpu_to_le32(L2CAP_EFS_DEFAULT_FLUSH_TO);
3067 break;
3068
3069 case L2CAP_MODE_STREAMING:
3070 efs.id = 1;
3071 efs.stype = L2CAP_SERV_BESTEFFORT;
3072 efs.msdu = cpu_to_le16(chan->local_msdu);
3073 efs.sdu_itime = cpu_to_le32(chan->local_sdu_itime);
3074 efs.acc_lat = 0;
3075 efs.flush_to = 0;
3076 break;
3077
3078 default:
3079 return;
3080 }
3081
3082 l2cap_add_conf_opt(ptr, L2CAP_CONF_EFS, sizeof(efs),
3083 (unsigned long) &efs, size);
3084}
3085
3086static void l2cap_ack_timeout(struct work_struct *work)
3087{
3088 struct l2cap_chan *chan = container_of(work, struct l2cap_chan,
3089 ack_timer.work);
3090 u16 frames_to_ack;
3091
3092 BT_DBG("chan %p", chan);
3093
3094 l2cap_chan_lock(chan);
3095
3096 frames_to_ack = __seq_offset(chan, chan->buffer_seq,
3097 chan->last_acked_seq);
3098
3099 if (frames_to_ack)
3100 l2cap_send_rr_or_rnr(chan, 0);
3101
3102 l2cap_chan_unlock(chan);
3103 l2cap_chan_put(chan);
3104}
3105
3106int l2cap_ertm_init(struct l2cap_chan *chan)
3107{
3108 int err;
3109
3110 chan->next_tx_seq = 0;
3111 chan->expected_tx_seq = 0;
3112 chan->expected_ack_seq = 0;
3113 chan->unacked_frames = 0;
3114 chan->buffer_seq = 0;
3115 chan->frames_sent = 0;
3116 chan->last_acked_seq = 0;
3117 chan->sdu = NULL;
3118 chan->sdu_last_frag = NULL;
3119 chan->sdu_len = 0;
3120
3121 skb_queue_head_init(&chan->tx_q);
3122
3123 chan->local_amp_id = AMP_ID_BREDR;
3124 chan->move_id = AMP_ID_BREDR;
3125 chan->move_state = L2CAP_MOVE_STABLE;
3126 chan->move_role = L2CAP_MOVE_ROLE_NONE;
3127
3128 if (chan->mode != L2CAP_MODE_ERTM)
3129 return 0;
3130
3131 chan->rx_state = L2CAP_RX_STATE_RECV;
3132 chan->tx_state = L2CAP_TX_STATE_XMIT;
3133
3134 INIT_DELAYED_WORK(&chan->retrans_timer, l2cap_retrans_timeout);
3135 INIT_DELAYED_WORK(&chan->monitor_timer, l2cap_monitor_timeout);
3136 INIT_DELAYED_WORK(&chan->ack_timer, l2cap_ack_timeout);
3137
3138 skb_queue_head_init(&chan->srej_q);
3139
3140 err = l2cap_seq_list_init(&chan->srej_list, chan->tx_win);
3141 if (err < 0)
3142 return err;
3143
3144 err = l2cap_seq_list_init(&chan->retrans_list, chan->remote_tx_win);
3145 if (err < 0)
3146 l2cap_seq_list_free(&chan->srej_list);
3147
3148 return err;
3149}
3150
3151static inline __u8 l2cap_select_mode(__u8 mode, __u16 remote_feat_mask)
3152{
3153 switch (mode) {
3154 case L2CAP_MODE_STREAMING:
3155 case L2CAP_MODE_ERTM:
3156 if (l2cap_mode_supported(mode, remote_feat_mask))
3157 return mode;
3158 /* fall through */
3159 default:
3160 return L2CAP_MODE_BASIC;
3161 }
3162}
3163
3164static inline bool __l2cap_ews_supported(struct l2cap_conn *conn)
3165{
3166 return ((conn->local_fixed_chan & L2CAP_FC_A2MP) &&
3167 (conn->feat_mask & L2CAP_FEAT_EXT_WINDOW));
3168}
3169
3170static inline bool __l2cap_efs_supported(struct l2cap_conn *conn)
3171{
3172 return ((conn->local_fixed_chan & L2CAP_FC_A2MP) &&
3173 (conn->feat_mask & L2CAP_FEAT_EXT_FLOW));
3174}
3175
3176static void __l2cap_set_ertm_timeouts(struct l2cap_chan *chan,
3177 struct l2cap_conf_rfc *rfc)
3178{
3179 if (chan->local_amp_id != AMP_ID_BREDR && chan->hs_hcon) {
3180 u64 ertm_to = chan->hs_hcon->hdev->amp_be_flush_to;
3181
3182 /* Class 1 devices have must have ERTM timeouts
3183 * exceeding the Link Supervision Timeout. The
3184 * default Link Supervision Timeout for AMP
3185 * controllers is 10 seconds.
3186 *
3187 * Class 1 devices use 0xffffffff for their
3188 * best-effort flush timeout, so the clamping logic
3189 * will result in a timeout that meets the above
3190 * requirement. ERTM timeouts are 16-bit values, so
3191 * the maximum timeout is 65.535 seconds.
3192 */
3193
3194 /* Convert timeout to milliseconds and round */
3195 ertm_to = DIV_ROUND_UP_ULL(ertm_to, 1000);
3196
3197 /* This is the recommended formula for class 2 devices
3198 * that start ERTM timers when packets are sent to the
3199 * controller.
3200 */
3201 ertm_to = 3 * ertm_to + 500;
3202
3203 if (ertm_to > 0xffff)
3204 ertm_to = 0xffff;
3205
3206 rfc->retrans_timeout = cpu_to_le16((u16) ertm_to);
3207 rfc->monitor_timeout = rfc->retrans_timeout;
3208 } else {
3209 rfc->retrans_timeout = cpu_to_le16(L2CAP_DEFAULT_RETRANS_TO);
3210 rfc->monitor_timeout = cpu_to_le16(L2CAP_DEFAULT_MONITOR_TO);
3211 }
3212}
3213
3214static inline void l2cap_txwin_setup(struct l2cap_chan *chan)
3215{
3216 if (chan->tx_win > L2CAP_DEFAULT_TX_WINDOW &&
3217 __l2cap_ews_supported(chan->conn)) {
3218 /* use extended control field */
3219 set_bit(FLAG_EXT_CTRL, &chan->flags);
3220 chan->tx_win_max = L2CAP_DEFAULT_EXT_WINDOW;
3221 } else {
3222 chan->tx_win = min_t(u16, chan->tx_win,
3223 L2CAP_DEFAULT_TX_WINDOW);
3224 chan->tx_win_max = L2CAP_DEFAULT_TX_WINDOW;
3225 }
3226 chan->ack_win = chan->tx_win;
3227}
3228
3229static int l2cap_build_conf_req(struct l2cap_chan *chan, void *data, size_t data_size)
3230{
3231 struct l2cap_conf_req *req = data;
3232 struct l2cap_conf_rfc rfc = { .mode = chan->mode };
3233 void *ptr = req->data;
3234 void *endptr = data + data_size;
3235 u16 size;
3236
3237 BT_DBG("chan %p", chan);
3238
3239 if (chan->num_conf_req || chan->num_conf_rsp)
3240 goto done;
3241
3242 switch (chan->mode) {
3243 case L2CAP_MODE_STREAMING:
3244 case L2CAP_MODE_ERTM:
3245 if (test_bit(CONF_STATE2_DEVICE, &chan->conf_state))
3246 break;
3247
3248 if (__l2cap_efs_supported(chan->conn))
3249 set_bit(FLAG_EFS_ENABLE, &chan->flags);
3250
3251 /* fall through */
3252 default:
3253 chan->mode = l2cap_select_mode(rfc.mode, chan->conn->feat_mask);
3254 break;
3255 }
3256
3257done:
3258 if (chan->imtu != L2CAP_DEFAULT_MTU)
3259 l2cap_add_conf_opt(&ptr, L2CAP_CONF_MTU, 2, chan->imtu, endptr - ptr);
3260
3261 switch (chan->mode) {
3262 case L2CAP_MODE_BASIC:
3263 if (disable_ertm)
3264 break;
3265
3266 if (!(chan->conn->feat_mask & L2CAP_FEAT_ERTM) &&
3267 !(chan->conn->feat_mask & L2CAP_FEAT_STREAMING))
3268 break;
3269
3270 rfc.mode = L2CAP_MODE_BASIC;
3271 rfc.txwin_size = 0;
3272 rfc.max_transmit = 0;
3273 rfc.retrans_timeout = 0;
3274 rfc.monitor_timeout = 0;
3275 rfc.max_pdu_size = 0;
3276
3277 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3278 (unsigned long) &rfc, endptr - ptr);
3279 break;
3280
3281 case L2CAP_MODE_ERTM:
3282 rfc.mode = L2CAP_MODE_ERTM;
3283 rfc.max_transmit = chan->max_tx;
3284
3285 __l2cap_set_ertm_timeouts(chan, &rfc);
3286
3287 size = min_t(u16, L2CAP_DEFAULT_MAX_PDU_SIZE, chan->conn->mtu -
3288 L2CAP_EXT_HDR_SIZE - L2CAP_SDULEN_SIZE -
3289 L2CAP_FCS_SIZE);
3290 rfc.max_pdu_size = cpu_to_le16(size);
3291
3292 l2cap_txwin_setup(chan);
3293
3294 rfc.txwin_size = min_t(u16, chan->tx_win,
3295 L2CAP_DEFAULT_TX_WINDOW);
3296
3297 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3298 (unsigned long) &rfc, endptr - ptr);
3299
3300 if (test_bit(FLAG_EFS_ENABLE, &chan->flags))
3301 l2cap_add_opt_efs(&ptr, chan, endptr - ptr);
3302
3303 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
3304 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EWS, 2,
3305 chan->tx_win, endptr - ptr);
3306
3307 if (chan->conn->feat_mask & L2CAP_FEAT_FCS)
3308 if (chan->fcs == L2CAP_FCS_NONE ||
3309 test_bit(CONF_RECV_NO_FCS, &chan->conf_state)) {
3310 chan->fcs = L2CAP_FCS_NONE;
3311 l2cap_add_conf_opt(&ptr, L2CAP_CONF_FCS, 1,
3312 chan->fcs, endptr - ptr);
3313 }
3314 break;
3315
3316 case L2CAP_MODE_STREAMING:
3317 l2cap_txwin_setup(chan);
3318 rfc.mode = L2CAP_MODE_STREAMING;
3319 rfc.txwin_size = 0;
3320 rfc.max_transmit = 0;
3321 rfc.retrans_timeout = 0;
3322 rfc.monitor_timeout = 0;
3323
3324 size = min_t(u16, L2CAP_DEFAULT_MAX_PDU_SIZE, chan->conn->mtu -
3325 L2CAP_EXT_HDR_SIZE - L2CAP_SDULEN_SIZE -
3326 L2CAP_FCS_SIZE);
3327 rfc.max_pdu_size = cpu_to_le16(size);
3328
3329 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3330 (unsigned long) &rfc, endptr - ptr);
3331
3332 if (test_bit(FLAG_EFS_ENABLE, &chan->flags))
3333 l2cap_add_opt_efs(&ptr, chan, endptr - ptr);
3334
3335 if (chan->conn->feat_mask & L2CAP_FEAT_FCS)
3336 if (chan->fcs == L2CAP_FCS_NONE ||
3337 test_bit(CONF_RECV_NO_FCS, &chan->conf_state)) {
3338 chan->fcs = L2CAP_FCS_NONE;
3339 l2cap_add_conf_opt(&ptr, L2CAP_CONF_FCS, 1,
3340 chan->fcs, endptr - ptr);
3341 }
3342 break;
3343 }
3344
3345 req->dcid = cpu_to_le16(chan->dcid);
3346 req->flags = cpu_to_le16(0);
3347
3348 return ptr - data;
3349}
3350
3351static int l2cap_parse_conf_req(struct l2cap_chan *chan, void *data, size_t data_size)
3352{
3353 struct l2cap_conf_rsp *rsp = data;
3354 void *ptr = rsp->data;
3355 void *endptr = data + data_size;
3356 void *req = chan->conf_req;
3357 int len = chan->conf_len;
3358 int type, hint, olen;
3359 unsigned long val;
3360 struct l2cap_conf_rfc rfc = { .mode = L2CAP_MODE_BASIC };
3361 struct l2cap_conf_efs efs;
3362 u8 remote_efs = 0;
3363 u16 mtu = L2CAP_DEFAULT_MTU;
3364 u16 result = L2CAP_CONF_SUCCESS;
3365 u16 size;
3366
3367 BT_DBG("chan %p", chan);
3368
3369 while (len >= L2CAP_CONF_OPT_SIZE) {
3370 len -= l2cap_get_conf_opt(&req, &type, &olen, &val);
3371 if (len < 0)
3372 break;
3373
3374 hint = type & L2CAP_CONF_HINT;
3375 type &= L2CAP_CONF_MASK;
3376
3377 switch (type) {
3378 case L2CAP_CONF_MTU:
3379 if (olen != 2)
3380 break;
3381 mtu = val;
3382 break;
3383
3384 case L2CAP_CONF_FLUSH_TO:
3385 if (olen != 2)
3386 break;
3387 chan->flush_to = val;
3388 break;
3389
3390 case L2CAP_CONF_QOS:
3391 break;
3392
3393 case L2CAP_CONF_RFC:
3394 if (olen != sizeof(rfc))
3395 break;
3396 memcpy(&rfc, (void *) val, olen);
3397 break;
3398
3399 case L2CAP_CONF_FCS:
3400 if (olen != 1)
3401 break;
3402 if (val == L2CAP_FCS_NONE)
3403 set_bit(CONF_RECV_NO_FCS, &chan->conf_state);
3404 break;
3405
3406 case L2CAP_CONF_EFS:
3407 if (olen != sizeof(efs))
3408 break;
3409 remote_efs = 1;
3410 memcpy(&efs, (void *) val, olen);
3411 break;
3412
3413 case L2CAP_CONF_EWS:
3414 if (olen != 2)
3415 break;
3416 if (!(chan->conn->local_fixed_chan & L2CAP_FC_A2MP))
3417 return -ECONNREFUSED;
3418 set_bit(FLAG_EXT_CTRL, &chan->flags);
3419 set_bit(CONF_EWS_RECV, &chan->conf_state);
3420 chan->tx_win_max = L2CAP_DEFAULT_EXT_WINDOW;
3421 chan->remote_tx_win = val;
3422 break;
3423
3424 default:
3425 if (hint)
3426 break;
3427 result = L2CAP_CONF_UNKNOWN;
3428 *((u8 *) ptr++) = type;
3429 break;
3430 }
3431 }
3432
3433 if (chan->num_conf_rsp || chan->num_conf_req > 1)
3434 goto done;
3435
3436 switch (chan->mode) {
3437 case L2CAP_MODE_STREAMING:
3438 case L2CAP_MODE_ERTM:
3439 if (!test_bit(CONF_STATE2_DEVICE, &chan->conf_state)) {
3440 chan->mode = l2cap_select_mode(rfc.mode,
3441 chan->conn->feat_mask);
3442 break;
3443 }
3444
3445 if (remote_efs) {
3446 if (__l2cap_efs_supported(chan->conn))
3447 set_bit(FLAG_EFS_ENABLE, &chan->flags);
3448 else
3449 return -ECONNREFUSED;
3450 }
3451
3452 if (chan->mode != rfc.mode)
3453 return -ECONNREFUSED;
3454
3455 break;
3456 }
3457
3458done:
3459 if (chan->mode != rfc.mode) {
3460 result = L2CAP_CONF_UNACCEPT;
3461 rfc.mode = chan->mode;
3462
3463 if (chan->num_conf_rsp == 1)
3464 return -ECONNREFUSED;
3465
3466 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3467 (unsigned long) &rfc, endptr - ptr);
3468 }
3469
3470 if (result == L2CAP_CONF_SUCCESS) {
3471 /* Configure output options and let the other side know
3472 * which ones we don't like. */
3473
3474 if (mtu < L2CAP_DEFAULT_MIN_MTU)
3475 result = L2CAP_CONF_UNACCEPT;
3476 else {
3477 chan->omtu = mtu;
3478 set_bit(CONF_MTU_DONE, &chan->conf_state);
3479 }
3480 l2cap_add_conf_opt(&ptr, L2CAP_CONF_MTU, 2, chan->omtu, endptr - ptr);
3481
3482 if (remote_efs) {
3483 if (chan->local_stype != L2CAP_SERV_NOTRAFIC &&
3484 efs.stype != L2CAP_SERV_NOTRAFIC &&
3485 efs.stype != chan->local_stype) {
3486
3487 result = L2CAP_CONF_UNACCEPT;
3488
3489 if (chan->num_conf_req >= 1)
3490 return -ECONNREFUSED;
3491
3492 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EFS,
3493 sizeof(efs),
3494 (unsigned long) &efs, endptr - ptr);
3495 } else {
3496 /* Send PENDING Conf Rsp */
3497 result = L2CAP_CONF_PENDING;
3498 set_bit(CONF_LOC_CONF_PEND, &chan->conf_state);
3499 }
3500 }
3501
3502 switch (rfc.mode) {
3503 case L2CAP_MODE_BASIC:
3504 chan->fcs = L2CAP_FCS_NONE;
3505 set_bit(CONF_MODE_DONE, &chan->conf_state);
3506 break;
3507
3508 case L2CAP_MODE_ERTM:
3509 if (!test_bit(CONF_EWS_RECV, &chan->conf_state))
3510 chan->remote_tx_win = rfc.txwin_size;
3511 else
3512 rfc.txwin_size = L2CAP_DEFAULT_TX_WINDOW;
3513
3514 chan->remote_max_tx = rfc.max_transmit;
3515
3516 size = min_t(u16, le16_to_cpu(rfc.max_pdu_size),
3517 chan->conn->mtu - L2CAP_EXT_HDR_SIZE -
3518 L2CAP_SDULEN_SIZE - L2CAP_FCS_SIZE);
3519 rfc.max_pdu_size = cpu_to_le16(size);
3520 chan->remote_mps = size;
3521
3522 __l2cap_set_ertm_timeouts(chan, &rfc);
3523
3524 set_bit(CONF_MODE_DONE, &chan->conf_state);
3525
3526 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC,
3527 sizeof(rfc), (unsigned long) &rfc, endptr - ptr);
3528
3529 if (test_bit(FLAG_EFS_ENABLE, &chan->flags)) {
3530 chan->remote_id = efs.id;
3531 chan->remote_stype = efs.stype;
3532 chan->remote_msdu = le16_to_cpu(efs.msdu);
3533 chan->remote_flush_to =
3534 le32_to_cpu(efs.flush_to);
3535 chan->remote_acc_lat =
3536 le32_to_cpu(efs.acc_lat);
3537 chan->remote_sdu_itime =
3538 le32_to_cpu(efs.sdu_itime);
3539 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EFS,
3540 sizeof(efs),
3541 (unsigned long) &efs, endptr - ptr);
3542 }
3543 break;
3544
3545 case L2CAP_MODE_STREAMING:
3546 size = min_t(u16, le16_to_cpu(rfc.max_pdu_size),
3547 chan->conn->mtu - L2CAP_EXT_HDR_SIZE -
3548 L2CAP_SDULEN_SIZE - L2CAP_FCS_SIZE);
3549 rfc.max_pdu_size = cpu_to_le16(size);
3550 chan->remote_mps = size;
3551
3552 set_bit(CONF_MODE_DONE, &chan->conf_state);
3553
3554 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3555 (unsigned long) &rfc, endptr - ptr);
3556
3557 break;
3558
3559 default:
3560 result = L2CAP_CONF_UNACCEPT;
3561
3562 memset(&rfc, 0, sizeof(rfc));
3563 rfc.mode = chan->mode;
3564 }
3565
3566 if (result == L2CAP_CONF_SUCCESS)
3567 set_bit(CONF_OUTPUT_DONE, &chan->conf_state);
3568 }
3569 rsp->scid = cpu_to_le16(chan->dcid);
3570 rsp->result = cpu_to_le16(result);
3571 rsp->flags = cpu_to_le16(0);
3572
3573 return ptr - data;
3574}
3575
3576static int l2cap_parse_conf_rsp(struct l2cap_chan *chan, void *rsp, int len,
3577 void *data, size_t size, u16 *result)
3578{
3579 struct l2cap_conf_req *req = data;
3580 void *ptr = req->data;
3581 void *endptr = data + size;
3582 int type, olen;
3583 unsigned long val;
3584 struct l2cap_conf_rfc rfc = { .mode = L2CAP_MODE_BASIC };
3585 struct l2cap_conf_efs efs;
3586
3587 BT_DBG("chan %p, rsp %p, len %d, req %p", chan, rsp, len, data);
3588
3589 while (len >= L2CAP_CONF_OPT_SIZE) {
3590 len -= l2cap_get_conf_opt(&rsp, &type, &olen, &val);
3591 if (len < 0)
3592 break;
3593
3594 switch (type) {
3595 case L2CAP_CONF_MTU:
3596 if (olen != 2)
3597 break;
3598 if (val < L2CAP_DEFAULT_MIN_MTU) {
3599 *result = L2CAP_CONF_UNACCEPT;
3600 chan->imtu = L2CAP_DEFAULT_MIN_MTU;
3601 } else
3602 chan->imtu = val;
3603 l2cap_add_conf_opt(&ptr, L2CAP_CONF_MTU, 2, chan->imtu,
3604 endptr - ptr);
3605 break;
3606
3607 case L2CAP_CONF_FLUSH_TO:
3608 if (olen != 2)
3609 break;
3610 chan->flush_to = val;
3611 l2cap_add_conf_opt(&ptr, L2CAP_CONF_FLUSH_TO, 2,
3612 chan->flush_to, endptr - ptr);
3613 break;
3614
3615 case L2CAP_CONF_RFC:
3616 if (olen != sizeof(rfc))
3617 break;
3618 memcpy(&rfc, (void *)val, olen);
3619 if (test_bit(CONF_STATE2_DEVICE, &chan->conf_state) &&
3620 rfc.mode != chan->mode)
3621 return -ECONNREFUSED;
3622 chan->fcs = 0;
3623 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3624 (unsigned long) &rfc, endptr - ptr);
3625 break;
3626
3627 case L2CAP_CONF_EWS:
3628 if (olen != 2)
3629 break;
3630 chan->ack_win = min_t(u16, val, chan->ack_win);
3631 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EWS, 2,
3632 chan->tx_win, endptr - ptr);
3633 break;
3634
3635 case L2CAP_CONF_EFS:
3636 if (olen != sizeof(efs))
3637 break;
3638 memcpy(&efs, (void *)val, olen);
3639 if (chan->local_stype != L2CAP_SERV_NOTRAFIC &&
3640 efs.stype != L2CAP_SERV_NOTRAFIC &&
3641 efs.stype != chan->local_stype)
3642 return -ECONNREFUSED;
3643 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EFS, sizeof(efs),
3644 (unsigned long) &efs, endptr - ptr);
3645 break;
3646
3647 case L2CAP_CONF_FCS:
3648 if (olen != 1)
3649 break;
3650 if (*result == L2CAP_CONF_PENDING)
3651 if (val == L2CAP_FCS_NONE)
3652 set_bit(CONF_RECV_NO_FCS,
3653 &chan->conf_state);
3654 break;
3655 }
3656 }
3657
3658 if (chan->mode == L2CAP_MODE_BASIC && chan->mode != rfc.mode)
3659 return -ECONNREFUSED;
3660
3661 chan->mode = rfc.mode;
3662
3663 if (*result == L2CAP_CONF_SUCCESS || *result == L2CAP_CONF_PENDING) {
3664 switch (rfc.mode) {
3665 case L2CAP_MODE_ERTM:
3666 chan->retrans_timeout = le16_to_cpu(rfc.retrans_timeout);
3667 chan->monitor_timeout = le16_to_cpu(rfc.monitor_timeout);
3668 chan->mps = le16_to_cpu(rfc.max_pdu_size);
3669 if (!test_bit(FLAG_EXT_CTRL, &chan->flags))
3670 chan->ack_win = min_t(u16, chan->ack_win,
3671 rfc.txwin_size);
3672
3673 if (test_bit(FLAG_EFS_ENABLE, &chan->flags)) {
3674 chan->local_msdu = le16_to_cpu(efs.msdu);
3675 chan->local_sdu_itime =
3676 le32_to_cpu(efs.sdu_itime);
3677 chan->local_acc_lat = le32_to_cpu(efs.acc_lat);
3678 chan->local_flush_to =
3679 le32_to_cpu(efs.flush_to);
3680 }
3681 break;
3682
3683 case L2CAP_MODE_STREAMING:
3684 chan->mps = le16_to_cpu(rfc.max_pdu_size);
3685 }
3686 }
3687
3688 req->dcid = cpu_to_le16(chan->dcid);
3689 req->flags = cpu_to_le16(0);
3690
3691 return ptr - data;
3692}
3693
3694static int l2cap_build_conf_rsp(struct l2cap_chan *chan, void *data,
3695 u16 result, u16 flags)
3696{
3697 struct l2cap_conf_rsp *rsp = data;
3698 void *ptr = rsp->data;
3699
3700 BT_DBG("chan %p", chan);
3701
3702 rsp->scid = cpu_to_le16(chan->dcid);
3703 rsp->result = cpu_to_le16(result);
3704 rsp->flags = cpu_to_le16(flags);
3705
3706 return ptr - data;
3707}
3708
3709void __l2cap_le_connect_rsp_defer(struct l2cap_chan *chan)
3710{
3711 struct l2cap_le_conn_rsp rsp;
3712 struct l2cap_conn *conn = chan->conn;
3713
3714 BT_DBG("chan %p", chan);
3715
3716 rsp.dcid = cpu_to_le16(chan->scid);
3717 rsp.mtu = cpu_to_le16(chan->imtu);
3718 rsp.mps = cpu_to_le16(chan->mps);
3719 rsp.credits = cpu_to_le16(chan->rx_credits);
3720 rsp.result = cpu_to_le16(L2CAP_CR_LE_SUCCESS);
3721
3722 l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CONN_RSP, sizeof(rsp),
3723 &rsp);
3724}
3725
3726void __l2cap_connect_rsp_defer(struct l2cap_chan *chan)
3727{
3728 struct l2cap_conn_rsp rsp;
3729 struct l2cap_conn *conn = chan->conn;
3730 u8 buf[128];
3731 u8 rsp_code;
3732
3733 rsp.scid = cpu_to_le16(chan->dcid);
3734 rsp.dcid = cpu_to_le16(chan->scid);
3735 rsp.result = cpu_to_le16(L2CAP_CR_SUCCESS);
3736 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
3737
3738 if (chan->hs_hcon)
3739 rsp_code = L2CAP_CREATE_CHAN_RSP;
3740 else
3741 rsp_code = L2CAP_CONN_RSP;
3742
3743 BT_DBG("chan %p rsp_code %u", chan, rsp_code);
3744
3745 l2cap_send_cmd(conn, chan->ident, rsp_code, sizeof(rsp), &rsp);
3746
3747 if (test_and_set_bit(CONF_REQ_SENT, &chan->conf_state))
3748 return;
3749
3750 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
3751 l2cap_build_conf_req(chan, buf, sizeof(buf)), buf);
3752 chan->num_conf_req++;
3753}
3754
3755static void l2cap_conf_rfc_get(struct l2cap_chan *chan, void *rsp, int len)
3756{
3757 int type, olen;
3758 unsigned long val;
3759 /* Use sane default values in case a misbehaving remote device
3760 * did not send an RFC or extended window size option.
3761 */
3762 u16 txwin_ext = chan->ack_win;
3763 struct l2cap_conf_rfc rfc = {
3764 .mode = chan->mode,
3765 .retrans_timeout = cpu_to_le16(L2CAP_DEFAULT_RETRANS_TO),
3766 .monitor_timeout = cpu_to_le16(L2CAP_DEFAULT_MONITOR_TO),
3767 .max_pdu_size = cpu_to_le16(chan->imtu),
3768 .txwin_size = min_t(u16, chan->ack_win, L2CAP_DEFAULT_TX_WINDOW),
3769 };
3770
3771 BT_DBG("chan %p, rsp %p, len %d", chan, rsp, len);
3772
3773 if ((chan->mode != L2CAP_MODE_ERTM) && (chan->mode != L2CAP_MODE_STREAMING))
3774 return;
3775
3776 while (len >= L2CAP_CONF_OPT_SIZE) {
3777 len -= l2cap_get_conf_opt(&rsp, &type, &olen, &val);
3778 if (len < 0)
3779 break;
3780
3781 switch (type) {
3782 case L2CAP_CONF_RFC:
3783 if (olen != sizeof(rfc))
3784 break;
3785 memcpy(&rfc, (void *)val, olen);
3786 break;
3787 case L2CAP_CONF_EWS:
3788 if (olen != 2)
3789 break;
3790 txwin_ext = val;
3791 break;
3792 }
3793 }
3794
3795 switch (rfc.mode) {
3796 case L2CAP_MODE_ERTM:
3797 chan->retrans_timeout = le16_to_cpu(rfc.retrans_timeout);
3798 chan->monitor_timeout = le16_to_cpu(rfc.monitor_timeout);
3799 chan->mps = le16_to_cpu(rfc.max_pdu_size);
3800 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
3801 chan->ack_win = min_t(u16, chan->ack_win, txwin_ext);
3802 else
3803 chan->ack_win = min_t(u16, chan->ack_win,
3804 rfc.txwin_size);
3805 break;
3806 case L2CAP_MODE_STREAMING:
3807 chan->mps = le16_to_cpu(rfc.max_pdu_size);
3808 }
3809}
3810
3811static inline int l2cap_command_rej(struct l2cap_conn *conn,
3812 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
3813 u8 *data)
3814{
3815 struct l2cap_cmd_rej_unk *rej = (struct l2cap_cmd_rej_unk *) data;
3816
3817 if (cmd_len < sizeof(*rej))
3818 return -EPROTO;
3819
3820 if (rej->reason != L2CAP_REJ_NOT_UNDERSTOOD)
3821 return 0;
3822
3823 if ((conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT) &&
3824 cmd->ident == conn->info_ident) {
3825 cancel_delayed_work(&conn->info_timer);
3826
3827 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
3828 conn->info_ident = 0;
3829
3830 l2cap_conn_start(conn);
3831 }
3832
3833 return 0;
3834}
3835
3836static struct l2cap_chan *l2cap_connect(struct l2cap_conn *conn,
3837 struct l2cap_cmd_hdr *cmd,
3838 u8 *data, u8 rsp_code, u8 amp_id)
3839{
3840 struct l2cap_conn_req *req = (struct l2cap_conn_req *) data;
3841 struct l2cap_conn_rsp rsp;
3842 struct l2cap_chan *chan = NULL, *pchan;
3843 int result, status = L2CAP_CS_NO_INFO;
3844
3845 u16 dcid = 0, scid = __le16_to_cpu(req->scid);
3846 __le16 psm = req->psm;
3847
3848 BT_DBG("psm 0x%2.2x scid 0x%4.4x", __le16_to_cpu(psm), scid);
3849
3850 /* Check if we have socket listening on psm */
3851 pchan = l2cap_global_chan_by_psm(BT_LISTEN, psm, &conn->hcon->src,
3852 &conn->hcon->dst, ACL_LINK);
3853 if (!pchan) {
3854 result = L2CAP_CR_BAD_PSM;
3855 goto sendresp;
3856 }
3857
3858 mutex_lock(&conn->chan_lock);
3859 l2cap_chan_lock(pchan);
3860
3861 /* Check if the ACL is secure enough (if not SDP) */
3862 if (psm != cpu_to_le16(L2CAP_PSM_SDP) &&
3863 !hci_conn_check_link_mode(conn->hcon)) {
3864 conn->disc_reason = HCI_ERROR_AUTH_FAILURE;
3865 result = L2CAP_CR_SEC_BLOCK;
3866 goto response;
3867 }
3868
3869 result = L2CAP_CR_NO_MEM;
3870
3871 /* Check for valid dynamic CID range (as per Erratum 3253) */
3872 if (scid < L2CAP_CID_DYN_START || scid > L2CAP_CID_DYN_END) {
3873 result = L2CAP_CR_INVALID_SCID;
3874 goto response;
3875 }
3876
3877 /* Check if we already have channel with that dcid */
3878 if (__l2cap_get_chan_by_dcid(conn, scid)) {
3879 result = L2CAP_CR_SCID_IN_USE;
3880 goto response;
3881 }
3882
3883 chan = pchan->ops->new_connection(pchan);
3884 if (!chan)
3885 goto response;
3886
3887 /* For certain devices (ex: HID mouse), support for authentication,
3888 * pairing and bonding is optional. For such devices, inorder to avoid
3889 * the ACL alive for too long after L2CAP disconnection, reset the ACL
3890 * disc_timeout back to HCI_DISCONN_TIMEOUT during L2CAP connect.
3891 */
3892 conn->hcon->disc_timeout = HCI_DISCONN_TIMEOUT;
3893
3894 bacpy(&chan->src, &conn->hcon->src);
3895 bacpy(&chan->dst, &conn->hcon->dst);
3896 chan->src_type = bdaddr_src_type(conn->hcon);
3897 chan->dst_type = bdaddr_dst_type(conn->hcon);
3898 chan->psm = psm;
3899 chan->dcid = scid;
3900 chan->local_amp_id = amp_id;
3901
3902 __l2cap_chan_add(conn, chan);
3903
3904 dcid = chan->scid;
3905
3906 __set_chan_timer(chan, chan->ops->get_sndtimeo(chan));
3907
3908 chan->ident = cmd->ident;
3909
3910 if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE) {
3911 if (l2cap_chan_check_security(chan, false)) {
3912 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) {
3913 l2cap_state_change(chan, BT_CONNECT2);
3914 result = L2CAP_CR_PEND;
3915 status = L2CAP_CS_AUTHOR_PEND;
3916 chan->ops->defer(chan);
3917 } else {
3918 /* Force pending result for AMP controllers.
3919 * The connection will succeed after the
3920 * physical link is up.
3921 */
3922 if (amp_id == AMP_ID_BREDR) {
3923 l2cap_state_change(chan, BT_CONFIG);
3924 result = L2CAP_CR_SUCCESS;
3925 } else {
3926 l2cap_state_change(chan, BT_CONNECT2);
3927 result = L2CAP_CR_PEND;
3928 }
3929 status = L2CAP_CS_NO_INFO;
3930 }
3931 } else {
3932 l2cap_state_change(chan, BT_CONNECT2);
3933 result = L2CAP_CR_PEND;
3934 status = L2CAP_CS_AUTHEN_PEND;
3935 }
3936 } else {
3937 l2cap_state_change(chan, BT_CONNECT2);
3938 result = L2CAP_CR_PEND;
3939 status = L2CAP_CS_NO_INFO;
3940 }
3941
3942response:
3943 l2cap_chan_unlock(pchan);
3944 mutex_unlock(&conn->chan_lock);
3945 l2cap_chan_put(pchan);
3946
3947sendresp:
3948 rsp.scid = cpu_to_le16(scid);
3949 rsp.dcid = cpu_to_le16(dcid);
3950 rsp.result = cpu_to_le16(result);
3951 rsp.status = cpu_to_le16(status);
3952 l2cap_send_cmd(conn, cmd->ident, rsp_code, sizeof(rsp), &rsp);
3953
3954 if (result == L2CAP_CR_PEND && status == L2CAP_CS_NO_INFO) {
3955 struct l2cap_info_req info;
3956 info.type = cpu_to_le16(L2CAP_IT_FEAT_MASK);
3957
3958 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_SENT;
3959 conn->info_ident = l2cap_get_ident(conn);
3960
3961 schedule_delayed_work(&conn->info_timer, L2CAP_INFO_TIMEOUT);
3962
3963 l2cap_send_cmd(conn, conn->info_ident, L2CAP_INFO_REQ,
3964 sizeof(info), &info);
3965 }
3966
3967 if (chan && !test_bit(CONF_REQ_SENT, &chan->conf_state) &&
3968 result == L2CAP_CR_SUCCESS) {
3969 u8 buf[128];
3970 set_bit(CONF_REQ_SENT, &chan->conf_state);
3971 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
3972 l2cap_build_conf_req(chan, buf, sizeof(buf)), buf);
3973 chan->num_conf_req++;
3974 }
3975
3976 return chan;
3977}
3978
3979static int l2cap_connect_req(struct l2cap_conn *conn,
3980 struct l2cap_cmd_hdr *cmd, u16 cmd_len, u8 *data)
3981{
3982 struct hci_dev *hdev = conn->hcon->hdev;
3983 struct hci_conn *hcon = conn->hcon;
3984
3985 if (cmd_len < sizeof(struct l2cap_conn_req))
3986 return -EPROTO;
3987
3988 hci_dev_lock(hdev);
3989 if (hci_dev_test_flag(hdev, HCI_MGMT) &&
3990 !test_and_set_bit(HCI_CONN_MGMT_CONNECTED, &hcon->flags))
3991 mgmt_device_connected(hdev, hcon, 0, NULL, 0);
3992 hci_dev_unlock(hdev);
3993
3994 l2cap_connect(conn, cmd, data, L2CAP_CONN_RSP, 0);
3995 return 0;
3996}
3997
3998static int l2cap_connect_create_rsp(struct l2cap_conn *conn,
3999 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4000 u8 *data)
4001{
4002 struct l2cap_conn_rsp *rsp = (struct l2cap_conn_rsp *) data;
4003 u16 scid, dcid, result, status;
4004 struct l2cap_chan *chan;
4005 u8 req[128];
4006 int err;
4007
4008 if (cmd_len < sizeof(*rsp))
4009 return -EPROTO;
4010
4011 scid = __le16_to_cpu(rsp->scid);
4012 dcid = __le16_to_cpu(rsp->dcid);
4013 result = __le16_to_cpu(rsp->result);
4014 status = __le16_to_cpu(rsp->status);
4015
4016 BT_DBG("dcid 0x%4.4x scid 0x%4.4x result 0x%2.2x status 0x%2.2x",
4017 dcid, scid, result, status);
4018
4019 mutex_lock(&conn->chan_lock);
4020
4021 if (scid) {
4022 chan = __l2cap_get_chan_by_scid(conn, scid);
4023 if (!chan) {
4024 err = -EBADSLT;
4025 goto unlock;
4026 }
4027 } else {
4028 chan = __l2cap_get_chan_by_ident(conn, cmd->ident);
4029 if (!chan) {
4030 err = -EBADSLT;
4031 goto unlock;
4032 }
4033 }
4034
4035 err = 0;
4036
4037 l2cap_chan_lock(chan);
4038
4039 switch (result) {
4040 case L2CAP_CR_SUCCESS:
4041 l2cap_state_change(chan, BT_CONFIG);
4042 chan->ident = 0;
4043 chan->dcid = dcid;
4044 clear_bit(CONF_CONNECT_PEND, &chan->conf_state);
4045
4046 if (test_and_set_bit(CONF_REQ_SENT, &chan->conf_state))
4047 break;
4048
4049 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
4050 l2cap_build_conf_req(chan, req, sizeof(req)), req);
4051 chan->num_conf_req++;
4052 break;
4053
4054 case L2CAP_CR_PEND:
4055 set_bit(CONF_CONNECT_PEND, &chan->conf_state);
4056 break;
4057
4058 default:
4059 l2cap_chan_del(chan, ECONNREFUSED);
4060 break;
4061 }
4062
4063 l2cap_chan_unlock(chan);
4064
4065unlock:
4066 mutex_unlock(&conn->chan_lock);
4067
4068 return err;
4069}
4070
4071static inline void set_default_fcs(struct l2cap_chan *chan)
4072{
4073 /* FCS is enabled only in ERTM or streaming mode, if one or both
4074 * sides request it.
4075 */
4076 if (chan->mode != L2CAP_MODE_ERTM && chan->mode != L2CAP_MODE_STREAMING)
4077 chan->fcs = L2CAP_FCS_NONE;
4078 else if (!test_bit(CONF_RECV_NO_FCS, &chan->conf_state))
4079 chan->fcs = L2CAP_FCS_CRC16;
4080}
4081
4082static void l2cap_send_efs_conf_rsp(struct l2cap_chan *chan, void *data,
4083 u8 ident, u16 flags)
4084{
4085 struct l2cap_conn *conn = chan->conn;
4086
4087 BT_DBG("conn %p chan %p ident %d flags 0x%4.4x", conn, chan, ident,
4088 flags);
4089
4090 clear_bit(CONF_LOC_CONF_PEND, &chan->conf_state);
4091 set_bit(CONF_OUTPUT_DONE, &chan->conf_state);
4092
4093 l2cap_send_cmd(conn, ident, L2CAP_CONF_RSP,
4094 l2cap_build_conf_rsp(chan, data,
4095 L2CAP_CONF_SUCCESS, flags), data);
4096}
4097
4098static void cmd_reject_invalid_cid(struct l2cap_conn *conn, u8 ident,
4099 u16 scid, u16 dcid)
4100{
4101 struct l2cap_cmd_rej_cid rej;
4102
4103 rej.reason = cpu_to_le16(L2CAP_REJ_INVALID_CID);
4104 rej.scid = __cpu_to_le16(scid);
4105 rej.dcid = __cpu_to_le16(dcid);
4106
4107 l2cap_send_cmd(conn, ident, L2CAP_COMMAND_REJ, sizeof(rej), &rej);
4108}
4109
4110static inline int l2cap_config_req(struct l2cap_conn *conn,
4111 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4112 u8 *data)
4113{
4114 struct l2cap_conf_req *req = (struct l2cap_conf_req *) data;
4115 u16 dcid, flags;
4116 u8 rsp[64];
4117 struct l2cap_chan *chan;
4118 int len, err = 0;
4119
4120 if (cmd_len < sizeof(*req))
4121 return -EPROTO;
4122
4123 dcid = __le16_to_cpu(req->dcid);
4124 flags = __le16_to_cpu(req->flags);
4125
4126 BT_DBG("dcid 0x%4.4x flags 0x%2.2x", dcid, flags);
4127
4128 chan = l2cap_get_chan_by_scid(conn, dcid);
4129 if (!chan) {
4130 cmd_reject_invalid_cid(conn, cmd->ident, dcid, 0);
4131 return 0;
4132 }
4133
4134 if (chan->state != BT_CONFIG && chan->state != BT_CONNECT2) {
4135 cmd_reject_invalid_cid(conn, cmd->ident, chan->scid,
4136 chan->dcid);
4137 goto unlock;
4138 }
4139
4140 /* Reject if config buffer is too small. */
4141 len = cmd_len - sizeof(*req);
4142 if (chan->conf_len + len > sizeof(chan->conf_req)) {
4143 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP,
4144 l2cap_build_conf_rsp(chan, rsp,
4145 L2CAP_CONF_REJECT, flags), rsp);
4146 goto unlock;
4147 }
4148
4149 /* Store config. */
4150 memcpy(chan->conf_req + chan->conf_len, req->data, len);
4151 chan->conf_len += len;
4152
4153 if (flags & L2CAP_CONF_FLAG_CONTINUATION) {
4154 /* Incomplete config. Send empty response. */
4155 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP,
4156 l2cap_build_conf_rsp(chan, rsp,
4157 L2CAP_CONF_SUCCESS, flags), rsp);
4158 goto unlock;
4159 }
4160
4161 /* Complete config. */
4162 len = l2cap_parse_conf_req(chan, rsp, sizeof(rsp));
4163 if (len < 0) {
4164 l2cap_send_disconn_req(chan, ECONNRESET);
4165 goto unlock;
4166 }
4167
4168 chan->ident = cmd->ident;
4169 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP, len, rsp);
4170 chan->num_conf_rsp++;
4171
4172 /* Reset config buffer. */
4173 chan->conf_len = 0;
4174
4175 if (!test_bit(CONF_OUTPUT_DONE, &chan->conf_state))
4176 goto unlock;
4177
4178 if (test_bit(CONF_INPUT_DONE, &chan->conf_state)) {
4179 set_default_fcs(chan);
4180
4181 if (chan->mode == L2CAP_MODE_ERTM ||
4182 chan->mode == L2CAP_MODE_STREAMING)
4183 err = l2cap_ertm_init(chan);
4184
4185 if (err < 0)
4186 l2cap_send_disconn_req(chan, -err);
4187 else
4188 l2cap_chan_ready(chan);
4189
4190 goto unlock;
4191 }
4192
4193 if (!test_and_set_bit(CONF_REQ_SENT, &chan->conf_state)) {
4194 u8 buf[64];
4195 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
4196 l2cap_build_conf_req(chan, buf, sizeof(buf)), buf);
4197 chan->num_conf_req++;
4198 }
4199
4200 /* Got Conf Rsp PENDING from remote side and assume we sent
4201 Conf Rsp PENDING in the code above */
4202 if (test_bit(CONF_REM_CONF_PEND, &chan->conf_state) &&
4203 test_bit(CONF_LOC_CONF_PEND, &chan->conf_state)) {
4204
4205 /* check compatibility */
4206
4207 /* Send rsp for BR/EDR channel */
4208 if (!chan->hs_hcon)
4209 l2cap_send_efs_conf_rsp(chan, rsp, cmd->ident, flags);
4210 else
4211 chan->ident = cmd->ident;
4212 }
4213
4214unlock:
4215 l2cap_chan_unlock(chan);
4216 return err;
4217}
4218
4219static inline int l2cap_config_rsp(struct l2cap_conn *conn,
4220 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4221 u8 *data)
4222{
4223 struct l2cap_conf_rsp *rsp = (struct l2cap_conf_rsp *)data;
4224 u16 scid, flags, result;
4225 struct l2cap_chan *chan;
4226 int len = cmd_len - sizeof(*rsp);
4227 int err = 0;
4228
4229 if (cmd_len < sizeof(*rsp))
4230 return -EPROTO;
4231
4232 scid = __le16_to_cpu(rsp->scid);
4233 flags = __le16_to_cpu(rsp->flags);
4234 result = __le16_to_cpu(rsp->result);
4235
4236 BT_DBG("scid 0x%4.4x flags 0x%2.2x result 0x%2.2x len %d", scid, flags,
4237 result, len);
4238
4239 chan = l2cap_get_chan_by_scid(conn, scid);
4240 if (!chan)
4241 return 0;
4242
4243 switch (result) {
4244 case L2CAP_CONF_SUCCESS:
4245 l2cap_conf_rfc_get(chan, rsp->data, len);
4246 clear_bit(CONF_REM_CONF_PEND, &chan->conf_state);
4247 break;
4248
4249 case L2CAP_CONF_PENDING:
4250 set_bit(CONF_REM_CONF_PEND, &chan->conf_state);
4251
4252 if (test_bit(CONF_LOC_CONF_PEND, &chan->conf_state)) {
4253 char buf[64];
4254
4255 len = l2cap_parse_conf_rsp(chan, rsp->data, len,
4256 buf, sizeof(buf), &result);
4257 if (len < 0) {
4258 l2cap_send_disconn_req(chan, ECONNRESET);
4259 goto done;
4260 }
4261
4262 if (!chan->hs_hcon) {
4263 l2cap_send_efs_conf_rsp(chan, buf, cmd->ident,
4264 0);
4265 } else {
4266 if (l2cap_check_efs(chan)) {
4267 amp_create_logical_link(chan);
4268 chan->ident = cmd->ident;
4269 }
4270 }
4271 }
4272 goto done;
4273
4274 case L2CAP_CONF_UNACCEPT:
4275 if (chan->num_conf_rsp <= L2CAP_CONF_MAX_CONF_RSP) {
4276 char req[64];
4277
4278 if (len > sizeof(req) - sizeof(struct l2cap_conf_req)) {
4279 l2cap_send_disconn_req(chan, ECONNRESET);
4280 goto done;
4281 }
4282
4283 /* throw out any old stored conf requests */
4284 result = L2CAP_CONF_SUCCESS;
4285 len = l2cap_parse_conf_rsp(chan, rsp->data, len,
4286 req, sizeof(req), &result);
4287 if (len < 0) {
4288 l2cap_send_disconn_req(chan, ECONNRESET);
4289 goto done;
4290 }
4291
4292 l2cap_send_cmd(conn, l2cap_get_ident(conn),
4293 L2CAP_CONF_REQ, len, req);
4294 chan->num_conf_req++;
4295 if (result != L2CAP_CONF_SUCCESS)
4296 goto done;
4297 break;
4298 }
4299 /* fall through */
4300
4301 default:
4302 l2cap_chan_set_err(chan, ECONNRESET);
4303
4304 __set_chan_timer(chan, L2CAP_DISC_REJ_TIMEOUT);
4305 l2cap_send_disconn_req(chan, ECONNRESET);
4306 goto done;
4307 }
4308
4309 if (flags & L2CAP_CONF_FLAG_CONTINUATION)
4310 goto done;
4311
4312 set_bit(CONF_INPUT_DONE, &chan->conf_state);
4313
4314 if (test_bit(CONF_OUTPUT_DONE, &chan->conf_state)) {
4315 set_default_fcs(chan);
4316
4317 if (chan->mode == L2CAP_MODE_ERTM ||
4318 chan->mode == L2CAP_MODE_STREAMING)
4319 err = l2cap_ertm_init(chan);
4320
4321 if (err < 0)
4322 l2cap_send_disconn_req(chan, -err);
4323 else
4324 l2cap_chan_ready(chan);
4325 }
4326
4327done:
4328 l2cap_chan_unlock(chan);
4329 return err;
4330}
4331
4332static inline int l2cap_disconnect_req(struct l2cap_conn *conn,
4333 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4334 u8 *data)
4335{
4336 struct l2cap_disconn_req *req = (struct l2cap_disconn_req *) data;
4337 struct l2cap_disconn_rsp rsp;
4338 u16 dcid, scid;
4339 struct l2cap_chan *chan;
4340
4341 if (cmd_len != sizeof(*req))
4342 return -EPROTO;
4343
4344 scid = __le16_to_cpu(req->scid);
4345 dcid = __le16_to_cpu(req->dcid);
4346
4347 BT_DBG("scid 0x%4.4x dcid 0x%4.4x", scid, dcid);
4348
4349 mutex_lock(&conn->chan_lock);
4350
4351 chan = __l2cap_get_chan_by_scid(conn, dcid);
4352 if (!chan) {
4353 mutex_unlock(&conn->chan_lock);
4354 cmd_reject_invalid_cid(conn, cmd->ident, dcid, scid);
4355 return 0;
4356 }
4357
4358 l2cap_chan_lock(chan);
4359
4360 rsp.dcid = cpu_to_le16(chan->scid);
4361 rsp.scid = cpu_to_le16(chan->dcid);
4362 l2cap_send_cmd(conn, cmd->ident, L2CAP_DISCONN_RSP, sizeof(rsp), &rsp);
4363
4364 chan->ops->set_shutdown(chan);
4365
4366 l2cap_chan_hold(chan);
4367 l2cap_chan_del(chan, ECONNRESET);
4368
4369 l2cap_chan_unlock(chan);
4370
4371 chan->ops->close(chan);
4372 l2cap_chan_put(chan);
4373
4374 mutex_unlock(&conn->chan_lock);
4375
4376 return 0;
4377}
4378
4379static inline int l2cap_disconnect_rsp(struct l2cap_conn *conn,
4380 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4381 u8 *data)
4382{
4383 struct l2cap_disconn_rsp *rsp = (struct l2cap_disconn_rsp *) data;
4384 u16 dcid, scid;
4385 struct l2cap_chan *chan;
4386
4387 if (cmd_len != sizeof(*rsp))
4388 return -EPROTO;
4389
4390 scid = __le16_to_cpu(rsp->scid);
4391 dcid = __le16_to_cpu(rsp->dcid);
4392
4393 BT_DBG("dcid 0x%4.4x scid 0x%4.4x", dcid, scid);
4394
4395 mutex_lock(&conn->chan_lock);
4396
4397 chan = __l2cap_get_chan_by_scid(conn, scid);
4398 if (!chan) {
4399 mutex_unlock(&conn->chan_lock);
4400 return 0;
4401 }
4402
4403 l2cap_chan_lock(chan);
4404
4405 if (chan->state != BT_DISCONN) {
4406 l2cap_chan_unlock(chan);
4407 mutex_unlock(&conn->chan_lock);
4408 return 0;
4409 }
4410
4411 l2cap_chan_hold(chan);
4412 l2cap_chan_del(chan, 0);
4413
4414 l2cap_chan_unlock(chan);
4415
4416 chan->ops->close(chan);
4417 l2cap_chan_put(chan);
4418
4419 mutex_unlock(&conn->chan_lock);
4420
4421 return 0;
4422}
4423
4424static inline int l2cap_information_req(struct l2cap_conn *conn,
4425 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4426 u8 *data)
4427{
4428 struct l2cap_info_req *req = (struct l2cap_info_req *) data;
4429 u16 type;
4430
4431 if (cmd_len != sizeof(*req))
4432 return -EPROTO;
4433
4434 type = __le16_to_cpu(req->type);
4435
4436 BT_DBG("type 0x%4.4x", type);
4437
4438 if (type == L2CAP_IT_FEAT_MASK) {
4439 u8 buf[8];
4440 u32 feat_mask = l2cap_feat_mask;
4441 struct l2cap_info_rsp *rsp = (struct l2cap_info_rsp *) buf;
4442 rsp->type = cpu_to_le16(L2CAP_IT_FEAT_MASK);
4443 rsp->result = cpu_to_le16(L2CAP_IR_SUCCESS);
4444 if (!disable_ertm)
4445 feat_mask |= L2CAP_FEAT_ERTM | L2CAP_FEAT_STREAMING
4446 | L2CAP_FEAT_FCS;
4447 if (conn->local_fixed_chan & L2CAP_FC_A2MP)
4448 feat_mask |= L2CAP_FEAT_EXT_FLOW
4449 | L2CAP_FEAT_EXT_WINDOW;
4450
4451 put_unaligned_le32(feat_mask, rsp->data);
4452 l2cap_send_cmd(conn, cmd->ident, L2CAP_INFO_RSP, sizeof(buf),
4453 buf);
4454 } else if (type == L2CAP_IT_FIXED_CHAN) {
4455 u8 buf[12];
4456 struct l2cap_info_rsp *rsp = (struct l2cap_info_rsp *) buf;
4457
4458 rsp->type = cpu_to_le16(L2CAP_IT_FIXED_CHAN);
4459 rsp->result = cpu_to_le16(L2CAP_IR_SUCCESS);
4460 rsp->data[0] = conn->local_fixed_chan;
4461 memset(rsp->data + 1, 0, 7);
4462 l2cap_send_cmd(conn, cmd->ident, L2CAP_INFO_RSP, sizeof(buf),
4463 buf);
4464 } else {
4465 struct l2cap_info_rsp rsp;
4466 rsp.type = cpu_to_le16(type);
4467 rsp.result = cpu_to_le16(L2CAP_IR_NOTSUPP);
4468 l2cap_send_cmd(conn, cmd->ident, L2CAP_INFO_RSP, sizeof(rsp),
4469 &rsp);
4470 }
4471
4472 return 0;
4473}
4474
4475static inline int l2cap_information_rsp(struct l2cap_conn *conn,
4476 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4477 u8 *data)
4478{
4479 struct l2cap_info_rsp *rsp = (struct l2cap_info_rsp *) data;
4480 u16 type, result;
4481
4482 if (cmd_len < sizeof(*rsp))
4483 return -EPROTO;
4484
4485 type = __le16_to_cpu(rsp->type);
4486 result = __le16_to_cpu(rsp->result);
4487
4488 BT_DBG("type 0x%4.4x result 0x%2.2x", type, result);
4489
4490 /* L2CAP Info req/rsp are unbound to channels, add extra checks */
4491 if (cmd->ident != conn->info_ident ||
4492 conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE)
4493 return 0;
4494
4495 cancel_delayed_work(&conn->info_timer);
4496
4497 if (result != L2CAP_IR_SUCCESS) {
4498 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
4499 conn->info_ident = 0;
4500
4501 l2cap_conn_start(conn);
4502
4503 return 0;
4504 }
4505
4506 switch (type) {
4507 case L2CAP_IT_FEAT_MASK:
4508 conn->feat_mask = get_unaligned_le32(rsp->data);
4509
4510 if (conn->feat_mask & L2CAP_FEAT_FIXED_CHAN) {
4511 struct l2cap_info_req req;
4512 req.type = cpu_to_le16(L2CAP_IT_FIXED_CHAN);
4513
4514 conn->info_ident = l2cap_get_ident(conn);
4515
4516 l2cap_send_cmd(conn, conn->info_ident,
4517 L2CAP_INFO_REQ, sizeof(req), &req);
4518 } else {
4519 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
4520 conn->info_ident = 0;
4521
4522 l2cap_conn_start(conn);
4523 }
4524 break;
4525
4526 case L2CAP_IT_FIXED_CHAN:
4527 conn->remote_fixed_chan = rsp->data[0];
4528 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
4529 conn->info_ident = 0;
4530
4531 l2cap_conn_start(conn);
4532 break;
4533 }
4534
4535 return 0;
4536}
4537
4538static int l2cap_create_channel_req(struct l2cap_conn *conn,
4539 struct l2cap_cmd_hdr *cmd,
4540 u16 cmd_len, void *data)
4541{
4542 struct l2cap_create_chan_req *req = data;
4543 struct l2cap_create_chan_rsp rsp;
4544 struct l2cap_chan *chan;
4545 struct hci_dev *hdev;
4546 u16 psm, scid;
4547
4548 if (cmd_len != sizeof(*req))
4549 return -EPROTO;
4550
4551 if (!(conn->local_fixed_chan & L2CAP_FC_A2MP))
4552 return -EINVAL;
4553
4554 psm = le16_to_cpu(req->psm);
4555 scid = le16_to_cpu(req->scid);
4556
4557 BT_DBG("psm 0x%2.2x, scid 0x%4.4x, amp_id %d", psm, scid, req->amp_id);
4558
4559 /* For controller id 0 make BR/EDR connection */
4560 if (req->amp_id == AMP_ID_BREDR) {
4561 l2cap_connect(conn, cmd, data, L2CAP_CREATE_CHAN_RSP,
4562 req->amp_id);
4563 return 0;
4564 }
4565
4566 /* Validate AMP controller id */
4567 hdev = hci_dev_get(req->amp_id);
4568 if (!hdev)
4569 goto error;
4570
4571 if (hdev->dev_type != HCI_AMP || !test_bit(HCI_UP, &hdev->flags)) {
4572 hci_dev_put(hdev);
4573 goto error;
4574 }
4575
4576 chan = l2cap_connect(conn, cmd, data, L2CAP_CREATE_CHAN_RSP,
4577 req->amp_id);
4578 if (chan) {
4579 struct amp_mgr *mgr = conn->hcon->amp_mgr;
4580 struct hci_conn *hs_hcon;
4581
4582 hs_hcon = hci_conn_hash_lookup_ba(hdev, AMP_LINK,
4583 &conn->hcon->dst);
4584 if (!hs_hcon) {
4585 hci_dev_put(hdev);
4586 cmd_reject_invalid_cid(conn, cmd->ident, chan->scid,
4587 chan->dcid);
4588 return 0;
4589 }
4590
4591 BT_DBG("mgr %p bredr_chan %p hs_hcon %p", mgr, chan, hs_hcon);
4592
4593 mgr->bredr_chan = chan;
4594 chan->hs_hcon = hs_hcon;
4595 chan->fcs = L2CAP_FCS_NONE;
4596 conn->mtu = hdev->block_mtu;
4597 }
4598
4599 hci_dev_put(hdev);
4600
4601 return 0;
4602
4603error:
4604 rsp.dcid = 0;
4605 rsp.scid = cpu_to_le16(scid);
4606 rsp.result = cpu_to_le16(L2CAP_CR_BAD_AMP);
4607 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
4608
4609 l2cap_send_cmd(conn, cmd->ident, L2CAP_CREATE_CHAN_RSP,
4610 sizeof(rsp), &rsp);
4611
4612 return 0;
4613}
4614
4615static void l2cap_send_move_chan_req(struct l2cap_chan *chan, u8 dest_amp_id)
4616{
4617 struct l2cap_move_chan_req req;
4618 u8 ident;
4619
4620 BT_DBG("chan %p, dest_amp_id %d", chan, dest_amp_id);
4621
4622 ident = l2cap_get_ident(chan->conn);
4623 chan->ident = ident;
4624
4625 req.icid = cpu_to_le16(chan->scid);
4626 req.dest_amp_id = dest_amp_id;
4627
4628 l2cap_send_cmd(chan->conn, ident, L2CAP_MOVE_CHAN_REQ, sizeof(req),
4629 &req);
4630
4631 __set_chan_timer(chan, L2CAP_MOVE_TIMEOUT);
4632}
4633
4634static void l2cap_send_move_chan_rsp(struct l2cap_chan *chan, u16 result)
4635{
4636 struct l2cap_move_chan_rsp rsp;
4637
4638 BT_DBG("chan %p, result 0x%4.4x", chan, result);
4639
4640 rsp.icid = cpu_to_le16(chan->dcid);
4641 rsp.result = cpu_to_le16(result);
4642
4643 l2cap_send_cmd(chan->conn, chan->ident, L2CAP_MOVE_CHAN_RSP,
4644 sizeof(rsp), &rsp);
4645}
4646
4647static void l2cap_send_move_chan_cfm(struct l2cap_chan *chan, u16 result)
4648{
4649 struct l2cap_move_chan_cfm cfm;
4650
4651 BT_DBG("chan %p, result 0x%4.4x", chan, result);
4652
4653 chan->ident = l2cap_get_ident(chan->conn);
4654
4655 cfm.icid = cpu_to_le16(chan->scid);
4656 cfm.result = cpu_to_le16(result);
4657
4658 l2cap_send_cmd(chan->conn, chan->ident, L2CAP_MOVE_CHAN_CFM,
4659 sizeof(cfm), &cfm);
4660
4661 __set_chan_timer(chan, L2CAP_MOVE_TIMEOUT);
4662}
4663
4664static void l2cap_send_move_chan_cfm_icid(struct l2cap_conn *conn, u16 icid)
4665{
4666 struct l2cap_move_chan_cfm cfm;
4667
4668 BT_DBG("conn %p, icid 0x%4.4x", conn, icid);
4669
4670 cfm.icid = cpu_to_le16(icid);
4671 cfm.result = cpu_to_le16(L2CAP_MC_UNCONFIRMED);
4672
4673 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_MOVE_CHAN_CFM,
4674 sizeof(cfm), &cfm);
4675}
4676
4677static void l2cap_send_move_chan_cfm_rsp(struct l2cap_conn *conn, u8 ident,
4678 u16 icid)
4679{
4680 struct l2cap_move_chan_cfm_rsp rsp;
4681
4682 BT_DBG("icid 0x%4.4x", icid);
4683
4684 rsp.icid = cpu_to_le16(icid);
4685 l2cap_send_cmd(conn, ident, L2CAP_MOVE_CHAN_CFM_RSP, sizeof(rsp), &rsp);
4686}
4687
4688static void __release_logical_link(struct l2cap_chan *chan)
4689{
4690 chan->hs_hchan = NULL;
4691 chan->hs_hcon = NULL;
4692
4693 /* Placeholder - release the logical link */
4694}
4695
4696static void l2cap_logical_fail(struct l2cap_chan *chan)
4697{
4698 /* Logical link setup failed */
4699 if (chan->state != BT_CONNECTED) {
4700 /* Create channel failure, disconnect */
4701 l2cap_send_disconn_req(chan, ECONNRESET);
4702 return;
4703 }
4704
4705 switch (chan->move_role) {
4706 case L2CAP_MOVE_ROLE_RESPONDER:
4707 l2cap_move_done(chan);
4708 l2cap_send_move_chan_rsp(chan, L2CAP_MR_NOT_SUPP);
4709 break;
4710 case L2CAP_MOVE_ROLE_INITIATOR:
4711 if (chan->move_state == L2CAP_MOVE_WAIT_LOGICAL_COMP ||
4712 chan->move_state == L2CAP_MOVE_WAIT_LOGICAL_CFM) {
4713 /* Remote has only sent pending or
4714 * success responses, clean up
4715 */
4716 l2cap_move_done(chan);
4717 }
4718
4719 /* Other amp move states imply that the move
4720 * has already aborted
4721 */
4722 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
4723 break;
4724 }
4725}
4726
4727static void l2cap_logical_finish_create(struct l2cap_chan *chan,
4728 struct hci_chan *hchan)
4729{
4730 struct l2cap_conf_rsp rsp;
4731
4732 chan->hs_hchan = hchan;
4733 chan->hs_hcon->l2cap_data = chan->conn;
4734
4735 l2cap_send_efs_conf_rsp(chan, &rsp, chan->ident, 0);
4736
4737 if (test_bit(CONF_INPUT_DONE, &chan->conf_state)) {
4738 int err;
4739
4740 set_default_fcs(chan);
4741
4742 err = l2cap_ertm_init(chan);
4743 if (err < 0)
4744 l2cap_send_disconn_req(chan, -err);
4745 else
4746 l2cap_chan_ready(chan);
4747 }
4748}
4749
4750static void l2cap_logical_finish_move(struct l2cap_chan *chan,
4751 struct hci_chan *hchan)
4752{
4753 chan->hs_hcon = hchan->conn;
4754 chan->hs_hcon->l2cap_data = chan->conn;
4755
4756 BT_DBG("move_state %d", chan->move_state);
4757
4758 switch (chan->move_state) {
4759 case L2CAP_MOVE_WAIT_LOGICAL_COMP:
4760 /* Move confirm will be sent after a success
4761 * response is received
4762 */
4763 chan->move_state = L2CAP_MOVE_WAIT_RSP_SUCCESS;
4764 break;
4765 case L2CAP_MOVE_WAIT_LOGICAL_CFM:
4766 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
4767 chan->move_state = L2CAP_MOVE_WAIT_LOCAL_BUSY;
4768 } else if (chan->move_role == L2CAP_MOVE_ROLE_INITIATOR) {
4769 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM_RSP;
4770 l2cap_send_move_chan_cfm(chan, L2CAP_MC_CONFIRMED);
4771 } else if (chan->move_role == L2CAP_MOVE_ROLE_RESPONDER) {
4772 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM;
4773 l2cap_send_move_chan_rsp(chan, L2CAP_MR_SUCCESS);
4774 }
4775 break;
4776 default:
4777 /* Move was not in expected state, free the channel */
4778 __release_logical_link(chan);
4779
4780 chan->move_state = L2CAP_MOVE_STABLE;
4781 }
4782}
4783
4784/* Call with chan locked */
4785void l2cap_logical_cfm(struct l2cap_chan *chan, struct hci_chan *hchan,
4786 u8 status)
4787{
4788 BT_DBG("chan %p, hchan %p, status %d", chan, hchan, status);
4789
4790 if (status) {
4791 l2cap_logical_fail(chan);
4792 __release_logical_link(chan);
4793 return;
4794 }
4795
4796 if (chan->state != BT_CONNECTED) {
4797 /* Ignore logical link if channel is on BR/EDR */
4798 if (chan->local_amp_id != AMP_ID_BREDR)
4799 l2cap_logical_finish_create(chan, hchan);
4800 } else {
4801 l2cap_logical_finish_move(chan, hchan);
4802 }
4803}
4804
4805void l2cap_move_start(struct l2cap_chan *chan)
4806{
4807 BT_DBG("chan %p", chan);
4808
4809 if (chan->local_amp_id == AMP_ID_BREDR) {
4810 if (chan->chan_policy != BT_CHANNEL_POLICY_AMP_PREFERRED)
4811 return;
4812 chan->move_role = L2CAP_MOVE_ROLE_INITIATOR;
4813 chan->move_state = L2CAP_MOVE_WAIT_PREPARE;
4814 /* Placeholder - start physical link setup */
4815 } else {
4816 chan->move_role = L2CAP_MOVE_ROLE_INITIATOR;
4817 chan->move_state = L2CAP_MOVE_WAIT_RSP_SUCCESS;
4818 chan->move_id = 0;
4819 l2cap_move_setup(chan);
4820 l2cap_send_move_chan_req(chan, 0);
4821 }
4822}
4823
4824static void l2cap_do_create(struct l2cap_chan *chan, int result,
4825 u8 local_amp_id, u8 remote_amp_id)
4826{
4827 BT_DBG("chan %p state %s %u -> %u", chan, state_to_string(chan->state),
4828 local_amp_id, remote_amp_id);
4829
4830 chan->fcs = L2CAP_FCS_NONE;
4831
4832 /* Outgoing channel on AMP */
4833 if (chan->state == BT_CONNECT) {
4834 if (result == L2CAP_CR_SUCCESS) {
4835 chan->local_amp_id = local_amp_id;
4836 l2cap_send_create_chan_req(chan, remote_amp_id);
4837 } else {
4838 /* Revert to BR/EDR connect */
4839 l2cap_send_conn_req(chan);
4840 }
4841
4842 return;
4843 }
4844
4845 /* Incoming channel on AMP */
4846 if (__l2cap_no_conn_pending(chan)) {
4847 struct l2cap_conn_rsp rsp;
4848 char buf[128];
4849 rsp.scid = cpu_to_le16(chan->dcid);
4850 rsp.dcid = cpu_to_le16(chan->scid);
4851
4852 if (result == L2CAP_CR_SUCCESS) {
4853 /* Send successful response */
4854 rsp.result = cpu_to_le16(L2CAP_CR_SUCCESS);
4855 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
4856 } else {
4857 /* Send negative response */
4858 rsp.result = cpu_to_le16(L2CAP_CR_NO_MEM);
4859 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
4860 }
4861
4862 l2cap_send_cmd(chan->conn, chan->ident, L2CAP_CREATE_CHAN_RSP,
4863 sizeof(rsp), &rsp);
4864
4865 if (result == L2CAP_CR_SUCCESS) {
4866 l2cap_state_change(chan, BT_CONFIG);
4867 set_bit(CONF_REQ_SENT, &chan->conf_state);
4868 l2cap_send_cmd(chan->conn, l2cap_get_ident(chan->conn),
4869 L2CAP_CONF_REQ,
4870 l2cap_build_conf_req(chan, buf, sizeof(buf)), buf);
4871 chan->num_conf_req++;
4872 }
4873 }
4874}
4875
4876static void l2cap_do_move_initiate(struct l2cap_chan *chan, u8 local_amp_id,
4877 u8 remote_amp_id)
4878{
4879 l2cap_move_setup(chan);
4880 chan->move_id = local_amp_id;
4881 chan->move_state = L2CAP_MOVE_WAIT_RSP;
4882
4883 l2cap_send_move_chan_req(chan, remote_amp_id);
4884}
4885
4886static void l2cap_do_move_respond(struct l2cap_chan *chan, int result)
4887{
4888 struct hci_chan *hchan = NULL;
4889
4890 /* Placeholder - get hci_chan for logical link */
4891
4892 if (hchan) {
4893 if (hchan->state == BT_CONNECTED) {
4894 /* Logical link is ready to go */
4895 chan->hs_hcon = hchan->conn;
4896 chan->hs_hcon->l2cap_data = chan->conn;
4897 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM;
4898 l2cap_send_move_chan_rsp(chan, L2CAP_MR_SUCCESS);
4899
4900 l2cap_logical_cfm(chan, hchan, L2CAP_MR_SUCCESS);
4901 } else {
4902 /* Wait for logical link to be ready */
4903 chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_CFM;
4904 }
4905 } else {
4906 /* Logical link not available */
4907 l2cap_send_move_chan_rsp(chan, L2CAP_MR_NOT_ALLOWED);
4908 }
4909}
4910
4911static void l2cap_do_move_cancel(struct l2cap_chan *chan, int result)
4912{
4913 if (chan->move_role == L2CAP_MOVE_ROLE_RESPONDER) {
4914 u8 rsp_result;
4915 if (result == -EINVAL)
4916 rsp_result = L2CAP_MR_BAD_ID;
4917 else
4918 rsp_result = L2CAP_MR_NOT_ALLOWED;
4919
4920 l2cap_send_move_chan_rsp(chan, rsp_result);
4921 }
4922
4923 chan->move_role = L2CAP_MOVE_ROLE_NONE;
4924 chan->move_state = L2CAP_MOVE_STABLE;
4925
4926 /* Restart data transmission */
4927 l2cap_ertm_send(chan);
4928}
4929
4930/* Invoke with locked chan */
4931void __l2cap_physical_cfm(struct l2cap_chan *chan, int result)
4932{
4933 u8 local_amp_id = chan->local_amp_id;
4934 u8 remote_amp_id = chan->remote_amp_id;
4935
4936 BT_DBG("chan %p, result %d, local_amp_id %d, remote_amp_id %d",
4937 chan, result, local_amp_id, remote_amp_id);
4938
4939 if (chan->state == BT_DISCONN || chan->state == BT_CLOSED) {
4940 l2cap_chan_unlock(chan);
4941 return;
4942 }
4943
4944 if (chan->state != BT_CONNECTED) {
4945 l2cap_do_create(chan, result, local_amp_id, remote_amp_id);
4946 } else if (result != L2CAP_MR_SUCCESS) {
4947 l2cap_do_move_cancel(chan, result);
4948 } else {
4949 switch (chan->move_role) {
4950 case L2CAP_MOVE_ROLE_INITIATOR:
4951 l2cap_do_move_initiate(chan, local_amp_id,
4952 remote_amp_id);
4953 break;
4954 case L2CAP_MOVE_ROLE_RESPONDER:
4955 l2cap_do_move_respond(chan, result);
4956 break;
4957 default:
4958 l2cap_do_move_cancel(chan, result);
4959 break;
4960 }
4961 }
4962}
4963
4964static inline int l2cap_move_channel_req(struct l2cap_conn *conn,
4965 struct l2cap_cmd_hdr *cmd,
4966 u16 cmd_len, void *data)
4967{
4968 struct l2cap_move_chan_req *req = data;
4969 struct l2cap_move_chan_rsp rsp;
4970 struct l2cap_chan *chan;
4971 u16 icid = 0;
4972 u16 result = L2CAP_MR_NOT_ALLOWED;
4973
4974 if (cmd_len != sizeof(*req))
4975 return -EPROTO;
4976
4977 icid = le16_to_cpu(req->icid);
4978
4979 BT_DBG("icid 0x%4.4x, dest_amp_id %d", icid, req->dest_amp_id);
4980
4981 if (!(conn->local_fixed_chan & L2CAP_FC_A2MP))
4982 return -EINVAL;
4983
4984 chan = l2cap_get_chan_by_dcid(conn, icid);
4985 if (!chan) {
4986 rsp.icid = cpu_to_le16(icid);
4987 rsp.result = cpu_to_le16(L2CAP_MR_NOT_ALLOWED);
4988 l2cap_send_cmd(conn, cmd->ident, L2CAP_MOVE_CHAN_RSP,
4989 sizeof(rsp), &rsp);
4990 return 0;
4991 }
4992
4993 chan->ident = cmd->ident;
4994
4995 if (chan->scid < L2CAP_CID_DYN_START ||
4996 chan->chan_policy == BT_CHANNEL_POLICY_BREDR_ONLY ||
4997 (chan->mode != L2CAP_MODE_ERTM &&
4998 chan->mode != L2CAP_MODE_STREAMING)) {
4999 result = L2CAP_MR_NOT_ALLOWED;
5000 goto send_move_response;
5001 }
5002
5003 if (chan->local_amp_id == req->dest_amp_id) {
5004 result = L2CAP_MR_SAME_ID;
5005 goto send_move_response;
5006 }
5007
5008 if (req->dest_amp_id != AMP_ID_BREDR) {
5009 struct hci_dev *hdev;
5010 hdev = hci_dev_get(req->dest_amp_id);
5011 if (!hdev || hdev->dev_type != HCI_AMP ||
5012 !test_bit(HCI_UP, &hdev->flags)) {
5013 if (hdev)
5014 hci_dev_put(hdev);
5015
5016 result = L2CAP_MR_BAD_ID;
5017 goto send_move_response;
5018 }
5019 hci_dev_put(hdev);
5020 }
5021
5022 /* Detect a move collision. Only send a collision response
5023 * if this side has "lost", otherwise proceed with the move.
5024 * The winner has the larger bd_addr.
5025 */
5026 if ((__chan_is_moving(chan) ||
5027 chan->move_role != L2CAP_MOVE_ROLE_NONE) &&
5028 bacmp(&conn->hcon->src, &conn->hcon->dst) > 0) {
5029 result = L2CAP_MR_COLLISION;
5030 goto send_move_response;
5031 }
5032
5033 chan->move_role = L2CAP_MOVE_ROLE_RESPONDER;
5034 l2cap_move_setup(chan);
5035 chan->move_id = req->dest_amp_id;
5036 icid = chan->dcid;
5037
5038 if (req->dest_amp_id == AMP_ID_BREDR) {
5039 /* Moving to BR/EDR */
5040 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
5041 chan->move_state = L2CAP_MOVE_WAIT_LOCAL_BUSY;
5042 result = L2CAP_MR_PEND;
5043 } else {
5044 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM;
5045 result = L2CAP_MR_SUCCESS;
5046 }
5047 } else {
5048 chan->move_state = L2CAP_MOVE_WAIT_PREPARE;
5049 /* Placeholder - uncomment when amp functions are available */
5050 /*amp_accept_physical(chan, req->dest_amp_id);*/
5051 result = L2CAP_MR_PEND;
5052 }
5053
5054send_move_response:
5055 l2cap_send_move_chan_rsp(chan, result);
5056
5057 l2cap_chan_unlock(chan);
5058
5059 return 0;
5060}
5061
5062static void l2cap_move_continue(struct l2cap_conn *conn, u16 icid, u16 result)
5063{
5064 struct l2cap_chan *chan;
5065 struct hci_chan *hchan = NULL;
5066
5067 chan = l2cap_get_chan_by_scid(conn, icid);
5068 if (!chan) {
5069 l2cap_send_move_chan_cfm_icid(conn, icid);
5070 return;
5071 }
5072
5073 __clear_chan_timer(chan);
5074 if (result == L2CAP_MR_PEND)
5075 __set_chan_timer(chan, L2CAP_MOVE_ERTX_TIMEOUT);
5076
5077 switch (chan->move_state) {
5078 case L2CAP_MOVE_WAIT_LOGICAL_COMP:
5079 /* Move confirm will be sent when logical link
5080 * is complete.
5081 */
5082 chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_CFM;
5083 break;
5084 case L2CAP_MOVE_WAIT_RSP_SUCCESS:
5085 if (result == L2CAP_MR_PEND) {
5086 break;
5087 } else if (test_bit(CONN_LOCAL_BUSY,
5088 &chan->conn_state)) {
5089 chan->move_state = L2CAP_MOVE_WAIT_LOCAL_BUSY;
5090 } else {
5091 /* Logical link is up or moving to BR/EDR,
5092 * proceed with move
5093 */
5094 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM_RSP;
5095 l2cap_send_move_chan_cfm(chan, L2CAP_MC_CONFIRMED);
5096 }
5097 break;
5098 case L2CAP_MOVE_WAIT_RSP:
5099 /* Moving to AMP */
5100 if (result == L2CAP_MR_SUCCESS) {
5101 /* Remote is ready, send confirm immediately
5102 * after logical link is ready
5103 */
5104 chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_CFM;
5105 } else {
5106 /* Both logical link and move success
5107 * are required to confirm
5108 */
5109 chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_COMP;
5110 }
5111
5112 /* Placeholder - get hci_chan for logical link */
5113 if (!hchan) {
5114 /* Logical link not available */
5115 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
5116 break;
5117 }
5118
5119 /* If the logical link is not yet connected, do not
5120 * send confirmation.
5121 */
5122 if (hchan->state != BT_CONNECTED)
5123 break;
5124
5125 /* Logical link is already ready to go */
5126
5127 chan->hs_hcon = hchan->conn;
5128 chan->hs_hcon->l2cap_data = chan->conn;
5129
5130 if (result == L2CAP_MR_SUCCESS) {
5131 /* Can confirm now */
5132 l2cap_send_move_chan_cfm(chan, L2CAP_MC_CONFIRMED);
5133 } else {
5134 /* Now only need move success
5135 * to confirm
5136 */
5137 chan->move_state = L2CAP_MOVE_WAIT_RSP_SUCCESS;
5138 }
5139
5140 l2cap_logical_cfm(chan, hchan, L2CAP_MR_SUCCESS);
5141 break;
5142 default:
5143 /* Any other amp move state means the move failed. */
5144 chan->move_id = chan->local_amp_id;
5145 l2cap_move_done(chan);
5146 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
5147 }
5148
5149 l2cap_chan_unlock(chan);
5150}
5151
5152static void l2cap_move_fail(struct l2cap_conn *conn, u8 ident, u16 icid,
5153 u16 result)
5154{
5155 struct l2cap_chan *chan;
5156
5157 chan = l2cap_get_chan_by_ident(conn, ident);
5158 if (!chan) {
5159 /* Could not locate channel, icid is best guess */
5160 l2cap_send_move_chan_cfm_icid(conn, icid);
5161 return;
5162 }
5163
5164 __clear_chan_timer(chan);
5165
5166 if (chan->move_role == L2CAP_MOVE_ROLE_INITIATOR) {
5167 if (result == L2CAP_MR_COLLISION) {
5168 chan->move_role = L2CAP_MOVE_ROLE_RESPONDER;
5169 } else {
5170 /* Cleanup - cancel move */
5171 chan->move_id = chan->local_amp_id;
5172 l2cap_move_done(chan);
5173 }
5174 }
5175
5176 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
5177
5178 l2cap_chan_unlock(chan);
5179}
5180
5181static int l2cap_move_channel_rsp(struct l2cap_conn *conn,
5182 struct l2cap_cmd_hdr *cmd,
5183 u16 cmd_len, void *data)
5184{
5185 struct l2cap_move_chan_rsp *rsp = data;
5186 u16 icid, result;
5187
5188 if (cmd_len != sizeof(*rsp))
5189 return -EPROTO;
5190
5191 icid = le16_to_cpu(rsp->icid);
5192 result = le16_to_cpu(rsp->result);
5193
5194 BT_DBG("icid 0x%4.4x, result 0x%4.4x", icid, result);
5195
5196 if (result == L2CAP_MR_SUCCESS || result == L2CAP_MR_PEND)
5197 l2cap_move_continue(conn, icid, result);
5198 else
5199 l2cap_move_fail(conn, cmd->ident, icid, result);
5200
5201 return 0;
5202}
5203
5204static int l2cap_move_channel_confirm(struct l2cap_conn *conn,
5205 struct l2cap_cmd_hdr *cmd,
5206 u16 cmd_len, void *data)
5207{
5208 struct l2cap_move_chan_cfm *cfm = data;
5209 struct l2cap_chan *chan;
5210 u16 icid, result;
5211
5212 if (cmd_len != sizeof(*cfm))
5213 return -EPROTO;
5214
5215 icid = le16_to_cpu(cfm->icid);
5216 result = le16_to_cpu(cfm->result);
5217
5218 BT_DBG("icid 0x%4.4x, result 0x%4.4x", icid, result);
5219
5220 chan = l2cap_get_chan_by_dcid(conn, icid);
5221 if (!chan) {
5222 /* Spec requires a response even if the icid was not found */
5223 l2cap_send_move_chan_cfm_rsp(conn, cmd->ident, icid);
5224 return 0;
5225 }
5226
5227 if (chan->move_state == L2CAP_MOVE_WAIT_CONFIRM) {
5228 if (result == L2CAP_MC_CONFIRMED) {
5229 chan->local_amp_id = chan->move_id;
5230 if (chan->local_amp_id == AMP_ID_BREDR)
5231 __release_logical_link(chan);
5232 } else {
5233 chan->move_id = chan->local_amp_id;
5234 }
5235
5236 l2cap_move_done(chan);
5237 }
5238
5239 l2cap_send_move_chan_cfm_rsp(conn, cmd->ident, icid);
5240
5241 l2cap_chan_unlock(chan);
5242
5243 return 0;
5244}
5245
5246static inline int l2cap_move_channel_confirm_rsp(struct l2cap_conn *conn,
5247 struct l2cap_cmd_hdr *cmd,
5248 u16 cmd_len, void *data)
5249{
5250 struct l2cap_move_chan_cfm_rsp *rsp = data;
5251 struct l2cap_chan *chan;
5252 u16 icid;
5253
5254 if (cmd_len != sizeof(*rsp))
5255 return -EPROTO;
5256
5257 icid = le16_to_cpu(rsp->icid);
5258
5259 BT_DBG("icid 0x%4.4x", icid);
5260
5261 chan = l2cap_get_chan_by_scid(conn, icid);
5262 if (!chan)
5263 return 0;
5264
5265 __clear_chan_timer(chan);
5266
5267 if (chan->move_state == L2CAP_MOVE_WAIT_CONFIRM_RSP) {
5268 chan->local_amp_id = chan->move_id;
5269
5270 if (chan->local_amp_id == AMP_ID_BREDR && chan->hs_hchan)
5271 __release_logical_link(chan);
5272
5273 l2cap_move_done(chan);
5274 }
5275
5276 l2cap_chan_unlock(chan);
5277
5278 return 0;
5279}
5280
5281static inline int l2cap_conn_param_update_req(struct l2cap_conn *conn,
5282 struct l2cap_cmd_hdr *cmd,
5283 u16 cmd_len, u8 *data)
5284{
5285 struct hci_conn *hcon = conn->hcon;
5286 struct l2cap_conn_param_update_req *req;
5287 struct l2cap_conn_param_update_rsp rsp;
5288 u16 min, max, latency, to_multiplier;
5289 int err;
5290
5291 if (hcon->role != HCI_ROLE_MASTER)
5292 return -EINVAL;
5293
5294 if (cmd_len != sizeof(struct l2cap_conn_param_update_req))
5295 return -EPROTO;
5296
5297 req = (struct l2cap_conn_param_update_req *) data;
5298 min = __le16_to_cpu(req->min);
5299 max = __le16_to_cpu(req->max);
5300 latency = __le16_to_cpu(req->latency);
5301 to_multiplier = __le16_to_cpu(req->to_multiplier);
5302
5303 BT_DBG("min 0x%4.4x max 0x%4.4x latency: 0x%4.4x Timeout: 0x%4.4x",
5304 min, max, latency, to_multiplier);
5305
5306 memset(&rsp, 0, sizeof(rsp));
5307
5308 err = hci_check_conn_params(min, max, latency, to_multiplier);
5309 if (err)
5310 rsp.result = cpu_to_le16(L2CAP_CONN_PARAM_REJECTED);
5311 else
5312 rsp.result = cpu_to_le16(L2CAP_CONN_PARAM_ACCEPTED);
5313
5314 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONN_PARAM_UPDATE_RSP,
5315 sizeof(rsp), &rsp);
5316
5317 if (!err) {
5318 u8 store_hint;
5319
5320 store_hint = hci_le_conn_update(hcon, min, max, latency,
5321 to_multiplier);
5322 mgmt_new_conn_param(hcon->hdev, &hcon->dst, hcon->dst_type,
5323 store_hint, min, max, latency,
5324 to_multiplier);
5325
5326 }
5327
5328 return 0;
5329}
5330
5331static int l2cap_le_connect_rsp(struct l2cap_conn *conn,
5332 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5333 u8 *data)
5334{
5335 struct l2cap_le_conn_rsp *rsp = (struct l2cap_le_conn_rsp *) data;
5336 struct hci_conn *hcon = conn->hcon;
5337 u16 dcid, mtu, mps, credits, result;
5338 struct l2cap_chan *chan;
5339 int err, sec_level;
5340
5341 if (cmd_len < sizeof(*rsp))
5342 return -EPROTO;
5343
5344 dcid = __le16_to_cpu(rsp->dcid);
5345 mtu = __le16_to_cpu(rsp->mtu);
5346 mps = __le16_to_cpu(rsp->mps);
5347 credits = __le16_to_cpu(rsp->credits);
5348 result = __le16_to_cpu(rsp->result);
5349
5350 if (result == L2CAP_CR_LE_SUCCESS && (mtu < 23 || mps < 23 ||
5351 dcid < L2CAP_CID_DYN_START ||
5352 dcid > L2CAP_CID_LE_DYN_END))
5353 return -EPROTO;
5354
5355 BT_DBG("dcid 0x%4.4x mtu %u mps %u credits %u result 0x%2.2x",
5356 dcid, mtu, mps, credits, result);
5357
5358 mutex_lock(&conn->chan_lock);
5359
5360 chan = __l2cap_get_chan_by_ident(conn, cmd->ident);
5361 if (!chan) {
5362 err = -EBADSLT;
5363 goto unlock;
5364 }
5365
5366 err = 0;
5367
5368 l2cap_chan_lock(chan);
5369
5370 switch (result) {
5371 case L2CAP_CR_LE_SUCCESS:
5372 if (__l2cap_get_chan_by_dcid(conn, dcid)) {
5373 err = -EBADSLT;
5374 break;
5375 }
5376
5377 chan->ident = 0;
5378 chan->dcid = dcid;
5379 chan->omtu = mtu;
5380 chan->remote_mps = mps;
5381 chan->tx_credits = credits;
5382 l2cap_chan_ready(chan);
5383 break;
5384
5385 case L2CAP_CR_LE_AUTHENTICATION:
5386 case L2CAP_CR_LE_ENCRYPTION:
5387 /* If we already have MITM protection we can't do
5388 * anything.
5389 */
5390 if (hcon->sec_level > BT_SECURITY_MEDIUM) {
5391 l2cap_chan_del(chan, ECONNREFUSED);
5392 break;
5393 }
5394
5395 sec_level = hcon->sec_level + 1;
5396 if (chan->sec_level < sec_level)
5397 chan->sec_level = sec_level;
5398
5399 /* We'll need to send a new Connect Request */
5400 clear_bit(FLAG_LE_CONN_REQ_SENT, &chan->flags);
5401
5402 smp_conn_security(hcon, chan->sec_level);
5403 break;
5404
5405 default:
5406 l2cap_chan_del(chan, ECONNREFUSED);
5407 break;
5408 }
5409
5410 l2cap_chan_unlock(chan);
5411
5412unlock:
5413 mutex_unlock(&conn->chan_lock);
5414
5415 return err;
5416}
5417
5418static inline int l2cap_bredr_sig_cmd(struct l2cap_conn *conn,
5419 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5420 u8 *data)
5421{
5422 int err = 0;
5423
5424 switch (cmd->code) {
5425 case L2CAP_COMMAND_REJ:
5426 l2cap_command_rej(conn, cmd, cmd_len, data);
5427 break;
5428
5429 case L2CAP_CONN_REQ:
5430 err = l2cap_connect_req(conn, cmd, cmd_len, data);
5431 break;
5432
5433 case L2CAP_CONN_RSP:
5434 case L2CAP_CREATE_CHAN_RSP:
5435 l2cap_connect_create_rsp(conn, cmd, cmd_len, data);
5436 break;
5437
5438 case L2CAP_CONF_REQ:
5439 err = l2cap_config_req(conn, cmd, cmd_len, data);
5440 break;
5441
5442 case L2CAP_CONF_RSP:
5443 l2cap_config_rsp(conn, cmd, cmd_len, data);
5444 break;
5445
5446 case L2CAP_DISCONN_REQ:
5447 err = l2cap_disconnect_req(conn, cmd, cmd_len, data);
5448 break;
5449
5450 case L2CAP_DISCONN_RSP:
5451 l2cap_disconnect_rsp(conn, cmd, cmd_len, data);
5452 break;
5453
5454 case L2CAP_ECHO_REQ:
5455 l2cap_send_cmd(conn, cmd->ident, L2CAP_ECHO_RSP, cmd_len, data);
5456 break;
5457
5458 case L2CAP_ECHO_RSP:
5459 break;
5460
5461 case L2CAP_INFO_REQ:
5462 err = l2cap_information_req(conn, cmd, cmd_len, data);
5463 break;
5464
5465 case L2CAP_INFO_RSP:
5466 l2cap_information_rsp(conn, cmd, cmd_len, data);
5467 break;
5468
5469 case L2CAP_CREATE_CHAN_REQ:
5470 err = l2cap_create_channel_req(conn, cmd, cmd_len, data);
5471 break;
5472
5473 case L2CAP_MOVE_CHAN_REQ:
5474 err = l2cap_move_channel_req(conn, cmd, cmd_len, data);
5475 break;
5476
5477 case L2CAP_MOVE_CHAN_RSP:
5478 l2cap_move_channel_rsp(conn, cmd, cmd_len, data);
5479 break;
5480
5481 case L2CAP_MOVE_CHAN_CFM:
5482 err = l2cap_move_channel_confirm(conn, cmd, cmd_len, data);
5483 break;
5484
5485 case L2CAP_MOVE_CHAN_CFM_RSP:
5486 l2cap_move_channel_confirm_rsp(conn, cmd, cmd_len, data);
5487 break;
5488
5489 default:
5490 BT_ERR("Unknown BR/EDR signaling command 0x%2.2x", cmd->code);
5491 err = -EINVAL;
5492 break;
5493 }
5494
5495 return err;
5496}
5497
5498static int l2cap_le_connect_req(struct l2cap_conn *conn,
5499 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5500 u8 *data)
5501{
5502 struct l2cap_le_conn_req *req = (struct l2cap_le_conn_req *) data;
5503 struct l2cap_le_conn_rsp rsp;
5504 struct l2cap_chan *chan, *pchan;
5505 u16 dcid, scid, credits, mtu, mps;
5506 __le16 psm;
5507 u8 result;
5508
5509 if (cmd_len != sizeof(*req))
5510 return -EPROTO;
5511
5512 scid = __le16_to_cpu(req->scid);
5513 mtu = __le16_to_cpu(req->mtu);
5514 mps = __le16_to_cpu(req->mps);
5515 psm = req->psm;
5516 dcid = 0;
5517 credits = 0;
5518
5519 if (mtu < 23 || mps < 23)
5520 return -EPROTO;
5521
5522 BT_DBG("psm 0x%2.2x scid 0x%4.4x mtu %u mps %u", __le16_to_cpu(psm),
5523 scid, mtu, mps);
5524
5525 /* Check if we have socket listening on psm */
5526 pchan = l2cap_global_chan_by_psm(BT_LISTEN, psm, &conn->hcon->src,
5527 &conn->hcon->dst, LE_LINK);
5528 if (!pchan) {
5529 result = L2CAP_CR_LE_BAD_PSM;
5530 chan = NULL;
5531 goto response;
5532 }
5533
5534 mutex_lock(&conn->chan_lock);
5535 l2cap_chan_lock(pchan);
5536
5537 if (!smp_sufficient_security(conn->hcon, pchan->sec_level,
5538 SMP_ALLOW_STK)) {
5539 result = L2CAP_CR_LE_AUTHENTICATION;
5540 chan = NULL;
5541 goto response_unlock;
5542 }
5543
5544 /* Check for valid dynamic CID range */
5545 if (scid < L2CAP_CID_DYN_START || scid > L2CAP_CID_LE_DYN_END) {
5546 result = L2CAP_CR_LE_INVALID_SCID;
5547 chan = NULL;
5548 goto response_unlock;
5549 }
5550
5551 /* Check if we already have channel with that dcid */
5552 if (__l2cap_get_chan_by_dcid(conn, scid)) {
5553 result = L2CAP_CR_LE_SCID_IN_USE;
5554 chan = NULL;
5555 goto response_unlock;
5556 }
5557
5558 chan = pchan->ops->new_connection(pchan);
5559 if (!chan) {
5560 result = L2CAP_CR_LE_NO_MEM;
5561 goto response_unlock;
5562 }
5563
5564 bacpy(&chan->src, &conn->hcon->src);
5565 bacpy(&chan->dst, &conn->hcon->dst);
5566 chan->src_type = bdaddr_src_type(conn->hcon);
5567 chan->dst_type = bdaddr_dst_type(conn->hcon);
5568 chan->psm = psm;
5569 chan->dcid = scid;
5570 chan->omtu = mtu;
5571 chan->remote_mps = mps;
5572
5573 __l2cap_chan_add(conn, chan);
5574
5575 l2cap_le_flowctl_init(chan, __le16_to_cpu(req->credits));
5576
5577 dcid = chan->scid;
5578 credits = chan->rx_credits;
5579
5580 __set_chan_timer(chan, chan->ops->get_sndtimeo(chan));
5581
5582 chan->ident = cmd->ident;
5583
5584 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) {
5585 l2cap_state_change(chan, BT_CONNECT2);
5586 /* The following result value is actually not defined
5587 * for LE CoC but we use it to let the function know
5588 * that it should bail out after doing its cleanup
5589 * instead of sending a response.
5590 */
5591 result = L2CAP_CR_PEND;
5592 chan->ops->defer(chan);
5593 } else {
5594 l2cap_chan_ready(chan);
5595 result = L2CAP_CR_LE_SUCCESS;
5596 }
5597
5598response_unlock:
5599 l2cap_chan_unlock(pchan);
5600 mutex_unlock(&conn->chan_lock);
5601 l2cap_chan_put(pchan);
5602
5603 if (result == L2CAP_CR_PEND)
5604 return 0;
5605
5606response:
5607 if (chan) {
5608 rsp.mtu = cpu_to_le16(chan->imtu);
5609 rsp.mps = cpu_to_le16(chan->mps);
5610 } else {
5611 rsp.mtu = 0;
5612 rsp.mps = 0;
5613 }
5614
5615 rsp.dcid = cpu_to_le16(dcid);
5616 rsp.credits = cpu_to_le16(credits);
5617 rsp.result = cpu_to_le16(result);
5618
5619 l2cap_send_cmd(conn, cmd->ident, L2CAP_LE_CONN_RSP, sizeof(rsp), &rsp);
5620
5621 return 0;
5622}
5623
5624static inline int l2cap_le_credits(struct l2cap_conn *conn,
5625 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5626 u8 *data)
5627{
5628 struct l2cap_le_credits *pkt;
5629 struct l2cap_chan *chan;
5630 u16 cid, credits, max_credits;
5631
5632 if (cmd_len != sizeof(*pkt))
5633 return -EPROTO;
5634
5635 pkt = (struct l2cap_le_credits *) data;
5636 cid = __le16_to_cpu(pkt->cid);
5637 credits = __le16_to_cpu(pkt->credits);
5638
5639 BT_DBG("cid 0x%4.4x credits 0x%4.4x", cid, credits);
5640
5641 chan = l2cap_get_chan_by_dcid(conn, cid);
5642 if (!chan)
5643 return -EBADSLT;
5644
5645 max_credits = LE_FLOWCTL_MAX_CREDITS - chan->tx_credits;
5646 if (credits > max_credits) {
5647 BT_ERR("LE credits overflow");
5648 l2cap_send_disconn_req(chan, ECONNRESET);
5649 l2cap_chan_unlock(chan);
5650
5651 /* Return 0 so that we don't trigger an unnecessary
5652 * command reject packet.
5653 */
5654 return 0;
5655 }
5656
5657 chan->tx_credits += credits;
5658
5659 /* Resume sending */
5660 l2cap_le_flowctl_send(chan);
5661
5662 if (chan->tx_credits)
5663 chan->ops->resume(chan);
5664
5665 l2cap_chan_unlock(chan);
5666
5667 return 0;
5668}
5669
5670static inline int l2cap_le_command_rej(struct l2cap_conn *conn,
5671 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5672 u8 *data)
5673{
5674 struct l2cap_cmd_rej_unk *rej = (struct l2cap_cmd_rej_unk *) data;
5675 struct l2cap_chan *chan;
5676
5677 if (cmd_len < sizeof(*rej))
5678 return -EPROTO;
5679
5680 mutex_lock(&conn->chan_lock);
5681
5682 chan = __l2cap_get_chan_by_ident(conn, cmd->ident);
5683 if (!chan)
5684 goto done;
5685
5686 l2cap_chan_lock(chan);
5687 l2cap_chan_del(chan, ECONNREFUSED);
5688 l2cap_chan_unlock(chan);
5689
5690done:
5691 mutex_unlock(&conn->chan_lock);
5692 return 0;
5693}
5694
5695static inline int l2cap_le_sig_cmd(struct l2cap_conn *conn,
5696 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5697 u8 *data)
5698{
5699 int err = 0;
5700
5701 switch (cmd->code) {
5702 case L2CAP_COMMAND_REJ:
5703 l2cap_le_command_rej(conn, cmd, cmd_len, data);
5704 break;
5705
5706 case L2CAP_CONN_PARAM_UPDATE_REQ:
5707 err = l2cap_conn_param_update_req(conn, cmd, cmd_len, data);
5708 break;
5709
5710 case L2CAP_CONN_PARAM_UPDATE_RSP:
5711 break;
5712
5713 case L2CAP_LE_CONN_RSP:
5714 l2cap_le_connect_rsp(conn, cmd, cmd_len, data);
5715 break;
5716
5717 case L2CAP_LE_CONN_REQ:
5718 err = l2cap_le_connect_req(conn, cmd, cmd_len, data);
5719 break;
5720
5721 case L2CAP_LE_CREDITS:
5722 err = l2cap_le_credits(conn, cmd, cmd_len, data);
5723 break;
5724
5725 case L2CAP_DISCONN_REQ:
5726 err = l2cap_disconnect_req(conn, cmd, cmd_len, data);
5727 break;
5728
5729 case L2CAP_DISCONN_RSP:
5730 l2cap_disconnect_rsp(conn, cmd, cmd_len, data);
5731 break;
5732
5733 default:
5734 BT_ERR("Unknown LE signaling command 0x%2.2x", cmd->code);
5735 err = -EINVAL;
5736 break;
5737 }
5738
5739 return err;
5740}
5741
5742static inline void l2cap_le_sig_channel(struct l2cap_conn *conn,
5743 struct sk_buff *skb)
5744{
5745 struct hci_conn *hcon = conn->hcon;
5746 struct l2cap_cmd_hdr *cmd;
5747 u16 len;
5748 int err;
5749
5750 if (hcon->type != LE_LINK)
5751 goto drop;
5752
5753 if (skb->len < L2CAP_CMD_HDR_SIZE)
5754 goto drop;
5755
5756 cmd = (void *) skb->data;
5757 skb_pull(skb, L2CAP_CMD_HDR_SIZE);
5758
5759 len = le16_to_cpu(cmd->len);
5760
5761 BT_DBG("code 0x%2.2x len %d id 0x%2.2x", cmd->code, len, cmd->ident);
5762
5763 if (len != skb->len || !cmd->ident) {
5764 BT_DBG("corrupted command");
5765 goto drop;
5766 }
5767
5768 err = l2cap_le_sig_cmd(conn, cmd, len, skb->data);
5769 if (err) {
5770 struct l2cap_cmd_rej_unk rej;
5771
5772 BT_ERR("Wrong link type (%d)", err);
5773
5774 rej.reason = cpu_to_le16(L2CAP_REJ_NOT_UNDERSTOOD);
5775 l2cap_send_cmd(conn, cmd->ident, L2CAP_COMMAND_REJ,
5776 sizeof(rej), &rej);
5777 }
5778
5779drop:
5780 kfree_skb(skb);
5781}
5782
5783static inline void l2cap_sig_channel(struct l2cap_conn *conn,
5784 struct sk_buff *skb)
5785{
5786 struct hci_conn *hcon = conn->hcon;
5787 u8 *data = skb->data;
5788 int len = skb->len;
5789 struct l2cap_cmd_hdr cmd;
5790 int err;
5791
5792 l2cap_raw_recv(conn, skb);
5793
5794 if (hcon->type != ACL_LINK)
5795 goto drop;
5796
5797 while (len >= L2CAP_CMD_HDR_SIZE) {
5798 u16 cmd_len;
5799 memcpy(&cmd, data, L2CAP_CMD_HDR_SIZE);
5800 data += L2CAP_CMD_HDR_SIZE;
5801 len -= L2CAP_CMD_HDR_SIZE;
5802
5803 cmd_len = le16_to_cpu(cmd.len);
5804
5805 BT_DBG("code 0x%2.2x len %d id 0x%2.2x", cmd.code, cmd_len,
5806 cmd.ident);
5807
5808 if (cmd_len > len || !cmd.ident) {
5809 BT_DBG("corrupted command");
5810 break;
5811 }
5812
5813 err = l2cap_bredr_sig_cmd(conn, &cmd, cmd_len, data);
5814 if (err) {
5815 struct l2cap_cmd_rej_unk rej;
5816
5817 BT_ERR("Wrong link type (%d)", err);
5818
5819 rej.reason = cpu_to_le16(L2CAP_REJ_NOT_UNDERSTOOD);
5820 l2cap_send_cmd(conn, cmd.ident, L2CAP_COMMAND_REJ,
5821 sizeof(rej), &rej);
5822 }
5823
5824 data += cmd_len;
5825 len -= cmd_len;
5826 }
5827
5828drop:
5829 kfree_skb(skb);
5830}
5831
5832static int l2cap_check_fcs(struct l2cap_chan *chan, struct sk_buff *skb)
5833{
5834 u16 our_fcs, rcv_fcs;
5835 int hdr_size;
5836
5837 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
5838 hdr_size = L2CAP_EXT_HDR_SIZE;
5839 else
5840 hdr_size = L2CAP_ENH_HDR_SIZE;
5841
5842 if (chan->fcs == L2CAP_FCS_CRC16) {
5843 skb_trim(skb, skb->len - L2CAP_FCS_SIZE);
5844 rcv_fcs = get_unaligned_le16(skb->data + skb->len);
5845 our_fcs = crc16(0, skb->data - hdr_size, skb->len + hdr_size);
5846
5847 if (our_fcs != rcv_fcs)
5848 return -EBADMSG;
5849 }
5850 return 0;
5851}
5852
5853static void l2cap_send_i_or_rr_or_rnr(struct l2cap_chan *chan)
5854{
5855 struct l2cap_ctrl control;
5856
5857 BT_DBG("chan %p", chan);
5858
5859 memset(&control, 0, sizeof(control));
5860 control.sframe = 1;
5861 control.final = 1;
5862 control.reqseq = chan->buffer_seq;
5863 set_bit(CONN_SEND_FBIT, &chan->conn_state);
5864
5865 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
5866 control.super = L2CAP_SUPER_RNR;
5867 l2cap_send_sframe(chan, &control);
5868 }
5869
5870 if (test_and_clear_bit(CONN_REMOTE_BUSY, &chan->conn_state) &&
5871 chan->unacked_frames > 0)
5872 __set_retrans_timer(chan);
5873
5874 /* Send pending iframes */
5875 l2cap_ertm_send(chan);
5876
5877 if (!test_bit(CONN_LOCAL_BUSY, &chan->conn_state) &&
5878 test_bit(CONN_SEND_FBIT, &chan->conn_state)) {
5879 /* F-bit wasn't sent in an s-frame or i-frame yet, so
5880 * send it now.
5881 */
5882 control.super = L2CAP_SUPER_RR;
5883 l2cap_send_sframe(chan, &control);
5884 }
5885}
5886
5887static void append_skb_frag(struct sk_buff *skb, struct sk_buff *new_frag,
5888 struct sk_buff **last_frag)
5889{
5890 /* skb->len reflects data in skb as well as all fragments
5891 * skb->data_len reflects only data in fragments
5892 */
5893 if (!skb_has_frag_list(skb))
5894 skb_shinfo(skb)->frag_list = new_frag;
5895
5896 new_frag->next = NULL;
5897
5898 (*last_frag)->next = new_frag;
5899 *last_frag = new_frag;
5900
5901 skb->len += new_frag->len;
5902 skb->data_len += new_frag->len;
5903 skb->truesize += new_frag->truesize;
5904}
5905
5906static int l2cap_reassemble_sdu(struct l2cap_chan *chan, struct sk_buff *skb,
5907 struct l2cap_ctrl *control)
5908{
5909 int err = -EINVAL;
5910
5911 switch (control->sar) {
5912 case L2CAP_SAR_UNSEGMENTED:
5913 if (chan->sdu)
5914 break;
5915
5916 err = chan->ops->recv(chan, skb);
5917 break;
5918
5919 case L2CAP_SAR_START:
5920 if (chan->sdu)
5921 break;
5922
5923 if (!pskb_may_pull(skb, L2CAP_SDULEN_SIZE))
5924 break;
5925
5926 chan->sdu_len = get_unaligned_le16(skb->data);
5927 skb_pull(skb, L2CAP_SDULEN_SIZE);
5928
5929 if (chan->sdu_len > chan->imtu) {
5930 err = -EMSGSIZE;
5931 break;
5932 }
5933
5934 if (skb->len >= chan->sdu_len)
5935 break;
5936
5937 chan->sdu = skb;
5938 chan->sdu_last_frag = skb;
5939
5940 skb = NULL;
5941 err = 0;
5942 break;
5943
5944 case L2CAP_SAR_CONTINUE:
5945 if (!chan->sdu)
5946 break;
5947
5948 append_skb_frag(chan->sdu, skb,
5949 &chan->sdu_last_frag);
5950 skb = NULL;
5951
5952 if (chan->sdu->len >= chan->sdu_len)
5953 break;
5954
5955 err = 0;
5956 break;
5957
5958 case L2CAP_SAR_END:
5959 if (!chan->sdu)
5960 break;
5961
5962 append_skb_frag(chan->sdu, skb,
5963 &chan->sdu_last_frag);
5964 skb = NULL;
5965
5966 if (chan->sdu->len != chan->sdu_len)
5967 break;
5968
5969 err = chan->ops->recv(chan, chan->sdu);
5970
5971 if (!err) {
5972 /* Reassembly complete */
5973 chan->sdu = NULL;
5974 chan->sdu_last_frag = NULL;
5975 chan->sdu_len = 0;
5976 }
5977 break;
5978 }
5979
5980 if (err) {
5981 kfree_skb(skb);
5982 kfree_skb(chan->sdu);
5983 chan->sdu = NULL;
5984 chan->sdu_last_frag = NULL;
5985 chan->sdu_len = 0;
5986 }
5987
5988 return err;
5989}
5990
5991static int l2cap_resegment(struct l2cap_chan *chan)
5992{
5993 /* Placeholder */
5994 return 0;
5995}
5996
5997void l2cap_chan_busy(struct l2cap_chan *chan, int busy)
5998{
5999 u8 event;
6000
6001 if (chan->mode != L2CAP_MODE_ERTM)
6002 return;
6003
6004 event = busy ? L2CAP_EV_LOCAL_BUSY_DETECTED : L2CAP_EV_LOCAL_BUSY_CLEAR;
6005 l2cap_tx(chan, NULL, NULL, event);
6006}
6007
6008static int l2cap_rx_queued_iframes(struct l2cap_chan *chan)
6009{
6010 int err = 0;
6011 /* Pass sequential frames to l2cap_reassemble_sdu()
6012 * until a gap is encountered.
6013 */
6014
6015 BT_DBG("chan %p", chan);
6016
6017 while (!test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
6018 struct sk_buff *skb;
6019 BT_DBG("Searching for skb with txseq %d (queue len %d)",
6020 chan->buffer_seq, skb_queue_len(&chan->srej_q));
6021
6022 skb = l2cap_ertm_seq_in_queue(&chan->srej_q, chan->buffer_seq);
6023
6024 if (!skb)
6025 break;
6026
6027 skb_unlink(skb, &chan->srej_q);
6028 chan->buffer_seq = __next_seq(chan, chan->buffer_seq);
6029 err = l2cap_reassemble_sdu(chan, skb, &bt_cb(skb)->l2cap);
6030 if (err)
6031 break;
6032 }
6033
6034 if (skb_queue_empty(&chan->srej_q)) {
6035 chan->rx_state = L2CAP_RX_STATE_RECV;
6036 l2cap_send_ack(chan);
6037 }
6038
6039 return err;
6040}
6041
6042static void l2cap_handle_srej(struct l2cap_chan *chan,
6043 struct l2cap_ctrl *control)
6044{
6045 struct sk_buff *skb;
6046
6047 BT_DBG("chan %p, control %p", chan, control);
6048
6049 if (control->reqseq == chan->next_tx_seq) {
6050 BT_DBG("Invalid reqseq %d, disconnecting", control->reqseq);
6051 l2cap_send_disconn_req(chan, ECONNRESET);
6052 return;
6053 }
6054
6055 skb = l2cap_ertm_seq_in_queue(&chan->tx_q, control->reqseq);
6056
6057 if (skb == NULL) {
6058 BT_DBG("Seq %d not available for retransmission",
6059 control->reqseq);
6060 return;
6061 }
6062
6063 if (chan->max_tx != 0 && bt_cb(skb)->l2cap.retries >= chan->max_tx) {
6064 BT_DBG("Retry limit exceeded (%d)", chan->max_tx);
6065 l2cap_send_disconn_req(chan, ECONNRESET);
6066 return;
6067 }
6068
6069 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6070
6071 if (control->poll) {
6072 l2cap_pass_to_tx(chan, control);
6073
6074 set_bit(CONN_SEND_FBIT, &chan->conn_state);
6075 l2cap_retransmit(chan, control);
6076 l2cap_ertm_send(chan);
6077
6078 if (chan->tx_state == L2CAP_TX_STATE_WAIT_F) {
6079 set_bit(CONN_SREJ_ACT, &chan->conn_state);
6080 chan->srej_save_reqseq = control->reqseq;
6081 }
6082 } else {
6083 l2cap_pass_to_tx_fbit(chan, control);
6084
6085 if (control->final) {
6086 if (chan->srej_save_reqseq != control->reqseq ||
6087 !test_and_clear_bit(CONN_SREJ_ACT,
6088 &chan->conn_state))
6089 l2cap_retransmit(chan, control);
6090 } else {
6091 l2cap_retransmit(chan, control);
6092 if (chan->tx_state == L2CAP_TX_STATE_WAIT_F) {
6093 set_bit(CONN_SREJ_ACT, &chan->conn_state);
6094 chan->srej_save_reqseq = control->reqseq;
6095 }
6096 }
6097 }
6098}
6099
6100static void l2cap_handle_rej(struct l2cap_chan *chan,
6101 struct l2cap_ctrl *control)
6102{
6103 struct sk_buff *skb;
6104
6105 BT_DBG("chan %p, control %p", chan, control);
6106
6107 if (control->reqseq == chan->next_tx_seq) {
6108 BT_DBG("Invalid reqseq %d, disconnecting", control->reqseq);
6109 l2cap_send_disconn_req(chan, ECONNRESET);
6110 return;
6111 }
6112
6113 skb = l2cap_ertm_seq_in_queue(&chan->tx_q, control->reqseq);
6114
6115 if (chan->max_tx && skb &&
6116 bt_cb(skb)->l2cap.retries >= chan->max_tx) {
6117 BT_DBG("Retry limit exceeded (%d)", chan->max_tx);
6118 l2cap_send_disconn_req(chan, ECONNRESET);
6119 return;
6120 }
6121
6122 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6123
6124 l2cap_pass_to_tx(chan, control);
6125
6126 if (control->final) {
6127 if (!test_and_clear_bit(CONN_REJ_ACT, &chan->conn_state))
6128 l2cap_retransmit_all(chan, control);
6129 } else {
6130 l2cap_retransmit_all(chan, control);
6131 l2cap_ertm_send(chan);
6132 if (chan->tx_state == L2CAP_TX_STATE_WAIT_F)
6133 set_bit(CONN_REJ_ACT, &chan->conn_state);
6134 }
6135}
6136
6137static u8 l2cap_classify_txseq(struct l2cap_chan *chan, u16 txseq)
6138{
6139 BT_DBG("chan %p, txseq %d", chan, txseq);
6140
6141 BT_DBG("last_acked_seq %d, expected_tx_seq %d", chan->last_acked_seq,
6142 chan->expected_tx_seq);
6143
6144 if (chan->rx_state == L2CAP_RX_STATE_SREJ_SENT) {
6145 if (__seq_offset(chan, txseq, chan->last_acked_seq) >=
6146 chan->tx_win) {
6147 /* See notes below regarding "double poll" and
6148 * invalid packets.
6149 */
6150 if (chan->tx_win <= ((chan->tx_win_max + 1) >> 1)) {
6151 BT_DBG("Invalid/Ignore - after SREJ");
6152 return L2CAP_TXSEQ_INVALID_IGNORE;
6153 } else {
6154 BT_DBG("Invalid - in window after SREJ sent");
6155 return L2CAP_TXSEQ_INVALID;
6156 }
6157 }
6158
6159 if (chan->srej_list.head == txseq) {
6160 BT_DBG("Expected SREJ");
6161 return L2CAP_TXSEQ_EXPECTED_SREJ;
6162 }
6163
6164 if (l2cap_ertm_seq_in_queue(&chan->srej_q, txseq)) {
6165 BT_DBG("Duplicate SREJ - txseq already stored");
6166 return L2CAP_TXSEQ_DUPLICATE_SREJ;
6167 }
6168
6169 if (l2cap_seq_list_contains(&chan->srej_list, txseq)) {
6170 BT_DBG("Unexpected SREJ - not requested");
6171 return L2CAP_TXSEQ_UNEXPECTED_SREJ;
6172 }
6173 }
6174
6175 if (chan->expected_tx_seq == txseq) {
6176 if (__seq_offset(chan, txseq, chan->last_acked_seq) >=
6177 chan->tx_win) {
6178 BT_DBG("Invalid - txseq outside tx window");
6179 return L2CAP_TXSEQ_INVALID;
6180 } else {
6181 BT_DBG("Expected");
6182 return L2CAP_TXSEQ_EXPECTED;
6183 }
6184 }
6185
6186 if (__seq_offset(chan, txseq, chan->last_acked_seq) <
6187 __seq_offset(chan, chan->expected_tx_seq, chan->last_acked_seq)) {
6188 BT_DBG("Duplicate - expected_tx_seq later than txseq");
6189 return L2CAP_TXSEQ_DUPLICATE;
6190 }
6191
6192 if (__seq_offset(chan, txseq, chan->last_acked_seq) >= chan->tx_win) {
6193 /* A source of invalid packets is a "double poll" condition,
6194 * where delays cause us to send multiple poll packets. If
6195 * the remote stack receives and processes both polls,
6196 * sequence numbers can wrap around in such a way that a
6197 * resent frame has a sequence number that looks like new data
6198 * with a sequence gap. This would trigger an erroneous SREJ
6199 * request.
6200 *
6201 * Fortunately, this is impossible with a tx window that's
6202 * less than half of the maximum sequence number, which allows
6203 * invalid frames to be safely ignored.
6204 *
6205 * With tx window sizes greater than half of the tx window
6206 * maximum, the frame is invalid and cannot be ignored. This
6207 * causes a disconnect.
6208 */
6209
6210 if (chan->tx_win <= ((chan->tx_win_max + 1) >> 1)) {
6211 BT_DBG("Invalid/Ignore - txseq outside tx window");
6212 return L2CAP_TXSEQ_INVALID_IGNORE;
6213 } else {
6214 BT_DBG("Invalid - txseq outside tx window");
6215 return L2CAP_TXSEQ_INVALID;
6216 }
6217 } else {
6218 BT_DBG("Unexpected - txseq indicates missing frames");
6219 return L2CAP_TXSEQ_UNEXPECTED;
6220 }
6221}
6222
6223static int l2cap_rx_state_recv(struct l2cap_chan *chan,
6224 struct l2cap_ctrl *control,
6225 struct sk_buff *skb, u8 event)
6226{
6227 int err = 0;
6228 bool skb_in_use = false;
6229
6230 BT_DBG("chan %p, control %p, skb %p, event %d", chan, control, skb,
6231 event);
6232
6233 switch (event) {
6234 case L2CAP_EV_RECV_IFRAME:
6235 switch (l2cap_classify_txseq(chan, control->txseq)) {
6236 case L2CAP_TXSEQ_EXPECTED:
6237 l2cap_pass_to_tx(chan, control);
6238
6239 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
6240 BT_DBG("Busy, discarding expected seq %d",
6241 control->txseq);
6242 break;
6243 }
6244
6245 chan->expected_tx_seq = __next_seq(chan,
6246 control->txseq);
6247
6248 chan->buffer_seq = chan->expected_tx_seq;
6249 skb_in_use = true;
6250
6251 err = l2cap_reassemble_sdu(chan, skb, control);
6252 if (err)
6253 break;
6254
6255 if (control->final) {
6256 if (!test_and_clear_bit(CONN_REJ_ACT,
6257 &chan->conn_state)) {
6258 control->final = 0;
6259 l2cap_retransmit_all(chan, control);
6260 l2cap_ertm_send(chan);
6261 }
6262 }
6263
6264 if (!test_bit(CONN_LOCAL_BUSY, &chan->conn_state))
6265 l2cap_send_ack(chan);
6266 break;
6267 case L2CAP_TXSEQ_UNEXPECTED:
6268 l2cap_pass_to_tx(chan, control);
6269
6270 /* Can't issue SREJ frames in the local busy state.
6271 * Drop this frame, it will be seen as missing
6272 * when local busy is exited.
6273 */
6274 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
6275 BT_DBG("Busy, discarding unexpected seq %d",
6276 control->txseq);
6277 break;
6278 }
6279
6280 /* There was a gap in the sequence, so an SREJ
6281 * must be sent for each missing frame. The
6282 * current frame is stored for later use.
6283 */
6284 skb_queue_tail(&chan->srej_q, skb);
6285 skb_in_use = true;
6286 BT_DBG("Queued %p (queue len %d)", skb,
6287 skb_queue_len(&chan->srej_q));
6288
6289 clear_bit(CONN_SREJ_ACT, &chan->conn_state);
6290 l2cap_seq_list_clear(&chan->srej_list);
6291 l2cap_send_srej(chan, control->txseq);
6292
6293 chan->rx_state = L2CAP_RX_STATE_SREJ_SENT;
6294 break;
6295 case L2CAP_TXSEQ_DUPLICATE:
6296 l2cap_pass_to_tx(chan, control);
6297 break;
6298 case L2CAP_TXSEQ_INVALID_IGNORE:
6299 break;
6300 case L2CAP_TXSEQ_INVALID:
6301 default:
6302 l2cap_send_disconn_req(chan, ECONNRESET);
6303 break;
6304 }
6305 break;
6306 case L2CAP_EV_RECV_RR:
6307 l2cap_pass_to_tx(chan, control);
6308 if (control->final) {
6309 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6310
6311 if (!test_and_clear_bit(CONN_REJ_ACT, &chan->conn_state) &&
6312 !__chan_is_moving(chan)) {
6313 control->final = 0;
6314 l2cap_retransmit_all(chan, control);
6315 }
6316
6317 l2cap_ertm_send(chan);
6318 } else if (control->poll) {
6319 l2cap_send_i_or_rr_or_rnr(chan);
6320 } else {
6321 if (test_and_clear_bit(CONN_REMOTE_BUSY,
6322 &chan->conn_state) &&
6323 chan->unacked_frames)
6324 __set_retrans_timer(chan);
6325
6326 l2cap_ertm_send(chan);
6327 }
6328 break;
6329 case L2CAP_EV_RECV_RNR:
6330 set_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6331 l2cap_pass_to_tx(chan, control);
6332 if (control && control->poll) {
6333 set_bit(CONN_SEND_FBIT, &chan->conn_state);
6334 l2cap_send_rr_or_rnr(chan, 0);
6335 }
6336 __clear_retrans_timer(chan);
6337 l2cap_seq_list_clear(&chan->retrans_list);
6338 break;
6339 case L2CAP_EV_RECV_REJ:
6340 l2cap_handle_rej(chan, control);
6341 break;
6342 case L2CAP_EV_RECV_SREJ:
6343 l2cap_handle_srej(chan, control);
6344 break;
6345 default:
6346 break;
6347 }
6348
6349 if (skb && !skb_in_use) {
6350 BT_DBG("Freeing %p", skb);
6351 kfree_skb(skb);
6352 }
6353
6354 return err;
6355}
6356
6357static int l2cap_rx_state_srej_sent(struct l2cap_chan *chan,
6358 struct l2cap_ctrl *control,
6359 struct sk_buff *skb, u8 event)
6360{
6361 int err = 0;
6362 u16 txseq = control->txseq;
6363 bool skb_in_use = false;
6364
6365 BT_DBG("chan %p, control %p, skb %p, event %d", chan, control, skb,
6366 event);
6367
6368 switch (event) {
6369 case L2CAP_EV_RECV_IFRAME:
6370 switch (l2cap_classify_txseq(chan, txseq)) {
6371 case L2CAP_TXSEQ_EXPECTED:
6372 /* Keep frame for reassembly later */
6373 l2cap_pass_to_tx(chan, control);
6374 skb_queue_tail(&chan->srej_q, skb);
6375 skb_in_use = true;
6376 BT_DBG("Queued %p (queue len %d)", skb,
6377 skb_queue_len(&chan->srej_q));
6378
6379 chan->expected_tx_seq = __next_seq(chan, txseq);
6380 break;
6381 case L2CAP_TXSEQ_EXPECTED_SREJ:
6382 l2cap_seq_list_pop(&chan->srej_list);
6383
6384 l2cap_pass_to_tx(chan, control);
6385 skb_queue_tail(&chan->srej_q, skb);
6386 skb_in_use = true;
6387 BT_DBG("Queued %p (queue len %d)", skb,
6388 skb_queue_len(&chan->srej_q));
6389
6390 err = l2cap_rx_queued_iframes(chan);
6391 if (err)
6392 break;
6393
6394 break;
6395 case L2CAP_TXSEQ_UNEXPECTED:
6396 /* Got a frame that can't be reassembled yet.
6397 * Save it for later, and send SREJs to cover
6398 * the missing frames.
6399 */
6400 skb_queue_tail(&chan->srej_q, skb);
6401 skb_in_use = true;
6402 BT_DBG("Queued %p (queue len %d)", skb,
6403 skb_queue_len(&chan->srej_q));
6404
6405 l2cap_pass_to_tx(chan, control);
6406 l2cap_send_srej(chan, control->txseq);
6407 break;
6408 case L2CAP_TXSEQ_UNEXPECTED_SREJ:
6409 /* This frame was requested with an SREJ, but
6410 * some expected retransmitted frames are
6411 * missing. Request retransmission of missing
6412 * SREJ'd frames.
6413 */
6414 skb_queue_tail(&chan->srej_q, skb);
6415 skb_in_use = true;
6416 BT_DBG("Queued %p (queue len %d)", skb,
6417 skb_queue_len(&chan->srej_q));
6418
6419 l2cap_pass_to_tx(chan, control);
6420 l2cap_send_srej_list(chan, control->txseq);
6421 break;
6422 case L2CAP_TXSEQ_DUPLICATE_SREJ:
6423 /* We've already queued this frame. Drop this copy. */
6424 l2cap_pass_to_tx(chan, control);
6425 break;
6426 case L2CAP_TXSEQ_DUPLICATE:
6427 /* Expecting a later sequence number, so this frame
6428 * was already received. Ignore it completely.
6429 */
6430 break;
6431 case L2CAP_TXSEQ_INVALID_IGNORE:
6432 break;
6433 case L2CAP_TXSEQ_INVALID:
6434 default:
6435 l2cap_send_disconn_req(chan, ECONNRESET);
6436 break;
6437 }
6438 break;
6439 case L2CAP_EV_RECV_RR:
6440 l2cap_pass_to_tx(chan, control);
6441 if (control->final) {
6442 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6443
6444 if (!test_and_clear_bit(CONN_REJ_ACT,
6445 &chan->conn_state)) {
6446 control->final = 0;
6447 l2cap_retransmit_all(chan, control);
6448 }
6449
6450 l2cap_ertm_send(chan);
6451 } else if (control->poll) {
6452 if (test_and_clear_bit(CONN_REMOTE_BUSY,
6453 &chan->conn_state) &&
6454 chan->unacked_frames) {
6455 __set_retrans_timer(chan);
6456 }
6457
6458 set_bit(CONN_SEND_FBIT, &chan->conn_state);
6459 l2cap_send_srej_tail(chan);
6460 } else {
6461 if (test_and_clear_bit(CONN_REMOTE_BUSY,
6462 &chan->conn_state) &&
6463 chan->unacked_frames)
6464 __set_retrans_timer(chan);
6465
6466 l2cap_send_ack(chan);
6467 }
6468 break;
6469 case L2CAP_EV_RECV_RNR:
6470 set_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6471 l2cap_pass_to_tx(chan, control);
6472 if (control->poll) {
6473 l2cap_send_srej_tail(chan);
6474 } else {
6475 struct l2cap_ctrl rr_control;
6476 memset(&rr_control, 0, sizeof(rr_control));
6477 rr_control.sframe = 1;
6478 rr_control.super = L2CAP_SUPER_RR;
6479 rr_control.reqseq = chan->buffer_seq;
6480 l2cap_send_sframe(chan, &rr_control);
6481 }
6482
6483 break;
6484 case L2CAP_EV_RECV_REJ:
6485 l2cap_handle_rej(chan, control);
6486 break;
6487 case L2CAP_EV_RECV_SREJ:
6488 l2cap_handle_srej(chan, control);
6489 break;
6490 }
6491
6492 if (skb && !skb_in_use) {
6493 BT_DBG("Freeing %p", skb);
6494 kfree_skb(skb);
6495 }
6496
6497 return err;
6498}
6499
6500static int l2cap_finish_move(struct l2cap_chan *chan)
6501{
6502 BT_DBG("chan %p", chan);
6503
6504 chan->rx_state = L2CAP_RX_STATE_RECV;
6505
6506 if (chan->hs_hcon)
6507 chan->conn->mtu = chan->hs_hcon->hdev->block_mtu;
6508 else
6509 chan->conn->mtu = chan->conn->hcon->hdev->acl_mtu;
6510
6511 return l2cap_resegment(chan);
6512}
6513
6514static int l2cap_rx_state_wait_p(struct l2cap_chan *chan,
6515 struct l2cap_ctrl *control,
6516 struct sk_buff *skb, u8 event)
6517{
6518 int err;
6519
6520 BT_DBG("chan %p, control %p, skb %p, event %d", chan, control, skb,
6521 event);
6522
6523 if (!control->poll)
6524 return -EPROTO;
6525
6526 l2cap_process_reqseq(chan, control->reqseq);
6527
6528 if (!skb_queue_empty(&chan->tx_q))
6529 chan->tx_send_head = skb_peek(&chan->tx_q);
6530 else
6531 chan->tx_send_head = NULL;
6532
6533 /* Rewind next_tx_seq to the point expected
6534 * by the receiver.
6535 */
6536 chan->next_tx_seq = control->reqseq;
6537 chan->unacked_frames = 0;
6538
6539 err = l2cap_finish_move(chan);
6540 if (err)
6541 return err;
6542
6543 set_bit(CONN_SEND_FBIT, &chan->conn_state);
6544 l2cap_send_i_or_rr_or_rnr(chan);
6545
6546 if (event == L2CAP_EV_RECV_IFRAME)
6547 return -EPROTO;
6548
6549 return l2cap_rx_state_recv(chan, control, NULL, event);
6550}
6551
6552static int l2cap_rx_state_wait_f(struct l2cap_chan *chan,
6553 struct l2cap_ctrl *control,
6554 struct sk_buff *skb, u8 event)
6555{
6556 int err;
6557
6558 if (!control->final)
6559 return -EPROTO;
6560
6561 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6562
6563 chan->rx_state = L2CAP_RX_STATE_RECV;
6564 l2cap_process_reqseq(chan, control->reqseq);
6565
6566 if (!skb_queue_empty(&chan->tx_q))
6567 chan->tx_send_head = skb_peek(&chan->tx_q);
6568 else
6569 chan->tx_send_head = NULL;
6570
6571 /* Rewind next_tx_seq to the point expected
6572 * by the receiver.
6573 */
6574 chan->next_tx_seq = control->reqseq;
6575 chan->unacked_frames = 0;
6576
6577 if (chan->hs_hcon)
6578 chan->conn->mtu = chan->hs_hcon->hdev->block_mtu;
6579 else
6580 chan->conn->mtu = chan->conn->hcon->hdev->acl_mtu;
6581
6582 err = l2cap_resegment(chan);
6583
6584 if (!err)
6585 err = l2cap_rx_state_recv(chan, control, skb, event);
6586
6587 return err;
6588}
6589
6590static bool __valid_reqseq(struct l2cap_chan *chan, u16 reqseq)
6591{
6592 /* Make sure reqseq is for a packet that has been sent but not acked */
6593 u16 unacked;
6594
6595 unacked = __seq_offset(chan, chan->next_tx_seq, chan->expected_ack_seq);
6596 return __seq_offset(chan, chan->next_tx_seq, reqseq) <= unacked;
6597}
6598
6599static int l2cap_rx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
6600 struct sk_buff *skb, u8 event)
6601{
6602 int err = 0;
6603
6604 BT_DBG("chan %p, control %p, skb %p, event %d, state %d", chan,
6605 control, skb, event, chan->rx_state);
6606
6607 if (__valid_reqseq(chan, control->reqseq)) {
6608 switch (chan->rx_state) {
6609 case L2CAP_RX_STATE_RECV:
6610 err = l2cap_rx_state_recv(chan, control, skb, event);
6611 break;
6612 case L2CAP_RX_STATE_SREJ_SENT:
6613 err = l2cap_rx_state_srej_sent(chan, control, skb,
6614 event);
6615 break;
6616 case L2CAP_RX_STATE_WAIT_P:
6617 err = l2cap_rx_state_wait_p(chan, control, skb, event);
6618 break;
6619 case L2CAP_RX_STATE_WAIT_F:
6620 err = l2cap_rx_state_wait_f(chan, control, skb, event);
6621 break;
6622 default:
6623 /* shut it down */
6624 break;
6625 }
6626 } else {
6627 BT_DBG("Invalid reqseq %d (next_tx_seq %d, expected_ack_seq %d",
6628 control->reqseq, chan->next_tx_seq,
6629 chan->expected_ack_seq);
6630 l2cap_send_disconn_req(chan, ECONNRESET);
6631 }
6632
6633 return err;
6634}
6635
6636static int l2cap_stream_rx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
6637 struct sk_buff *skb)
6638{
6639 BT_DBG("chan %p, control %p, skb %p, state %d", chan, control, skb,
6640 chan->rx_state);
6641
6642 if (l2cap_classify_txseq(chan, control->txseq) ==
6643 L2CAP_TXSEQ_EXPECTED) {
6644 l2cap_pass_to_tx(chan, control);
6645
6646 BT_DBG("buffer_seq %d->%d", chan->buffer_seq,
6647 __next_seq(chan, chan->buffer_seq));
6648
6649 chan->buffer_seq = __next_seq(chan, chan->buffer_seq);
6650
6651 l2cap_reassemble_sdu(chan, skb, control);
6652 } else {
6653 if (chan->sdu) {
6654 kfree_skb(chan->sdu);
6655 chan->sdu = NULL;
6656 }
6657 chan->sdu_last_frag = NULL;
6658 chan->sdu_len = 0;
6659
6660 if (skb) {
6661 BT_DBG("Freeing %p", skb);
6662 kfree_skb(skb);
6663 }
6664 }
6665
6666 chan->last_acked_seq = control->txseq;
6667 chan->expected_tx_seq = __next_seq(chan, control->txseq);
6668
6669 return 0;
6670}
6671
6672static int l2cap_data_rcv(struct l2cap_chan *chan, struct sk_buff *skb)
6673{
6674 struct l2cap_ctrl *control = &bt_cb(skb)->l2cap;
6675 u16 len;
6676 u8 event;
6677
6678 __unpack_control(chan, skb);
6679
6680 len = skb->len;
6681
6682 /*
6683 * We can just drop the corrupted I-frame here.
6684 * Receiver will miss it and start proper recovery
6685 * procedures and ask for retransmission.
6686 */
6687 if (l2cap_check_fcs(chan, skb))
6688 goto drop;
6689
6690 if (!control->sframe && control->sar == L2CAP_SAR_START)
6691 len -= L2CAP_SDULEN_SIZE;
6692
6693 if (chan->fcs == L2CAP_FCS_CRC16)
6694 len -= L2CAP_FCS_SIZE;
6695
6696 if (len > chan->mps) {
6697 l2cap_send_disconn_req(chan, ECONNRESET);
6698 goto drop;
6699 }
6700
6701 if ((chan->mode == L2CAP_MODE_ERTM ||
6702 chan->mode == L2CAP_MODE_STREAMING) && sk_filter(chan->data, skb))
6703 goto drop;
6704
6705 if (!control->sframe) {
6706 int err;
6707
6708 BT_DBG("iframe sar %d, reqseq %d, final %d, txseq %d",
6709 control->sar, control->reqseq, control->final,
6710 control->txseq);
6711
6712 /* Validate F-bit - F=0 always valid, F=1 only
6713 * valid in TX WAIT_F
6714 */
6715 if (control->final && chan->tx_state != L2CAP_TX_STATE_WAIT_F)
6716 goto drop;
6717
6718 if (chan->mode != L2CAP_MODE_STREAMING) {
6719 event = L2CAP_EV_RECV_IFRAME;
6720 err = l2cap_rx(chan, control, skb, event);
6721 } else {
6722 err = l2cap_stream_rx(chan, control, skb);
6723 }
6724
6725 if (err)
6726 l2cap_send_disconn_req(chan, ECONNRESET);
6727 } else {
6728 const u8 rx_func_to_event[4] = {
6729 L2CAP_EV_RECV_RR, L2CAP_EV_RECV_REJ,
6730 L2CAP_EV_RECV_RNR, L2CAP_EV_RECV_SREJ
6731 };
6732
6733 /* Only I-frames are expected in streaming mode */
6734 if (chan->mode == L2CAP_MODE_STREAMING)
6735 goto drop;
6736
6737 BT_DBG("sframe reqseq %d, final %d, poll %d, super %d",
6738 control->reqseq, control->final, control->poll,
6739 control->super);
6740
6741 if (len != 0) {
6742 BT_ERR("Trailing bytes: %d in sframe", len);
6743 l2cap_send_disconn_req(chan, ECONNRESET);
6744 goto drop;
6745 }
6746
6747 /* Validate F and P bits */
6748 if (control->final && (control->poll ||
6749 chan->tx_state != L2CAP_TX_STATE_WAIT_F))
6750 goto drop;
6751
6752 event = rx_func_to_event[control->super];
6753 if (l2cap_rx(chan, control, skb, event))
6754 l2cap_send_disconn_req(chan, ECONNRESET);
6755 }
6756
6757 return 0;
6758
6759drop:
6760 kfree_skb(skb);
6761 return 0;
6762}
6763
6764static void l2cap_chan_le_send_credits(struct l2cap_chan *chan)
6765{
6766 struct l2cap_conn *conn = chan->conn;
6767 struct l2cap_le_credits pkt;
6768 u16 return_credits;
6769
6770 return_credits = ((chan->imtu / chan->mps) + 1) - chan->rx_credits;
6771
6772 if (!return_credits)
6773 return;
6774
6775 BT_DBG("chan %p returning %u credits to sender", chan, return_credits);
6776
6777 chan->rx_credits += return_credits;
6778
6779 pkt.cid = cpu_to_le16(chan->scid);
6780 pkt.credits = cpu_to_le16(return_credits);
6781
6782 chan->ident = l2cap_get_ident(conn);
6783
6784 l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CREDITS, sizeof(pkt), &pkt);
6785}
6786
6787static int l2cap_le_recv(struct l2cap_chan *chan, struct sk_buff *skb)
6788{
6789 int err;
6790
6791 BT_DBG("SDU reassemble complete: chan %p skb->len %u", chan, skb->len);
6792
6793 /* Wait recv to confirm reception before updating the credits */
6794 err = chan->ops->recv(chan, skb);
6795
6796 /* Update credits whenever an SDU is received */
6797 l2cap_chan_le_send_credits(chan);
6798
6799 return err;
6800}
6801
6802static int l2cap_le_data_rcv(struct l2cap_chan *chan, struct sk_buff *skb)
6803{
6804 int err;
6805
6806 if (!chan->rx_credits) {
6807 BT_ERR("No credits to receive LE L2CAP data");
6808 l2cap_send_disconn_req(chan, ECONNRESET);
6809 return -ENOBUFS;
6810 }
6811
6812 if (chan->imtu < skb->len) {
6813 BT_ERR("Too big LE L2CAP PDU");
6814 return -ENOBUFS;
6815 }
6816
6817 chan->rx_credits--;
6818 BT_DBG("rx_credits %u -> %u", chan->rx_credits + 1, chan->rx_credits);
6819
6820 /* Update if remote had run out of credits, this should only happens
6821 * if the remote is not using the entire MPS.
6822 */
6823 if (!chan->rx_credits)
6824 l2cap_chan_le_send_credits(chan);
6825
6826 err = 0;
6827
6828 if (!chan->sdu) {
6829 u16 sdu_len;
6830
6831 sdu_len = get_unaligned_le16(skb->data);
6832 skb_pull(skb, L2CAP_SDULEN_SIZE);
6833
6834 BT_DBG("Start of new SDU. sdu_len %u skb->len %u imtu %u",
6835 sdu_len, skb->len, chan->imtu);
6836
6837 if (sdu_len > chan->imtu) {
6838 BT_ERR("Too big LE L2CAP SDU length received");
6839 err = -EMSGSIZE;
6840 goto failed;
6841 }
6842
6843 if (skb->len > sdu_len) {
6844 BT_ERR("Too much LE L2CAP data received");
6845 err = -EINVAL;
6846 goto failed;
6847 }
6848
6849 if (skb->len == sdu_len)
6850 return l2cap_le_recv(chan, skb);
6851
6852 chan->sdu = skb;
6853 chan->sdu_len = sdu_len;
6854 chan->sdu_last_frag = skb;
6855
6856 /* Detect if remote is not able to use the selected MPS */
6857 if (skb->len + L2CAP_SDULEN_SIZE < chan->mps) {
6858 u16 mps_len = skb->len + L2CAP_SDULEN_SIZE;
6859
6860 /* Adjust the number of credits */
6861 BT_DBG("chan->mps %u -> %u", chan->mps, mps_len);
6862 chan->mps = mps_len;
6863 l2cap_chan_le_send_credits(chan);
6864 }
6865
6866 return 0;
6867 }
6868
6869 BT_DBG("SDU fragment. chan->sdu->len %u skb->len %u chan->sdu_len %u",
6870 chan->sdu->len, skb->len, chan->sdu_len);
6871
6872 if (chan->sdu->len + skb->len > chan->sdu_len) {
6873 BT_ERR("Too much LE L2CAP data received");
6874 err = -EINVAL;
6875 goto failed;
6876 }
6877
6878 append_skb_frag(chan->sdu, skb, &chan->sdu_last_frag);
6879 skb = NULL;
6880
6881 if (chan->sdu->len == chan->sdu_len) {
6882 err = l2cap_le_recv(chan, chan->sdu);
6883 if (!err) {
6884 chan->sdu = NULL;
6885 chan->sdu_last_frag = NULL;
6886 chan->sdu_len = 0;
6887 }
6888 }
6889
6890failed:
6891 if (err) {
6892 kfree_skb(skb);
6893 kfree_skb(chan->sdu);
6894 chan->sdu = NULL;
6895 chan->sdu_last_frag = NULL;
6896 chan->sdu_len = 0;
6897 }
6898
6899 /* We can't return an error here since we took care of the skb
6900 * freeing internally. An error return would cause the caller to
6901 * do a double-free of the skb.
6902 */
6903 return 0;
6904}
6905
6906static void l2cap_data_channel(struct l2cap_conn *conn, u16 cid,
6907 struct sk_buff *skb)
6908{
6909 struct l2cap_chan *chan;
6910
6911 chan = l2cap_get_chan_by_scid(conn, cid);
6912 if (!chan) {
6913 if (cid == L2CAP_CID_A2MP) {
6914 chan = a2mp_channel_create(conn, skb);
6915 if (!chan) {
6916 kfree_skb(skb);
6917 return;
6918 }
6919
6920 l2cap_chan_lock(chan);
6921 } else {
6922 BT_DBG("unknown cid 0x%4.4x", cid);
6923 /* Drop packet and return */
6924 kfree_skb(skb);
6925 return;
6926 }
6927 }
6928
6929 BT_DBG("chan %p, len %d", chan, skb->len);
6930
6931 /* If we receive data on a fixed channel before the info req/rsp
6932 * procdure is done simply assume that the channel is supported
6933 * and mark it as ready.
6934 */
6935 if (chan->chan_type == L2CAP_CHAN_FIXED)
6936 l2cap_chan_ready(chan);
6937
6938 if (chan->state != BT_CONNECTED)
6939 goto drop;
6940
6941 switch (chan->mode) {
6942 case L2CAP_MODE_LE_FLOWCTL:
6943 if (l2cap_le_data_rcv(chan, skb) < 0)
6944 goto drop;
6945
6946 goto done;
6947
6948 case L2CAP_MODE_BASIC:
6949 /* If socket recv buffers overflows we drop data here
6950 * which is *bad* because L2CAP has to be reliable.
6951 * But we don't have any other choice. L2CAP doesn't
6952 * provide flow control mechanism. */
6953
6954 if (chan->imtu < skb->len) {
6955 BT_ERR("Dropping L2CAP data: receive buffer overflow");
6956 goto drop;
6957 }
6958
6959 if (!chan->ops->recv(chan, skb))
6960 goto done;
6961 break;
6962
6963 case L2CAP_MODE_ERTM:
6964 case L2CAP_MODE_STREAMING:
6965 l2cap_data_rcv(chan, skb);
6966 goto done;
6967
6968 default:
6969 BT_DBG("chan %p: bad mode 0x%2.2x", chan, chan->mode);
6970 break;
6971 }
6972
6973drop:
6974 kfree_skb(skb);
6975
6976done:
6977 l2cap_chan_unlock(chan);
6978}
6979
6980static void l2cap_conless_channel(struct l2cap_conn *conn, __le16 psm,
6981 struct sk_buff *skb)
6982{
6983 struct hci_conn *hcon = conn->hcon;
6984 struct l2cap_chan *chan;
6985
6986 if (hcon->type != ACL_LINK)
6987 goto free_skb;
6988
6989 chan = l2cap_global_chan_by_psm(0, psm, &hcon->src, &hcon->dst,
6990 ACL_LINK);
6991 if (!chan)
6992 goto free_skb;
6993
6994 BT_DBG("chan %p, len %d", chan, skb->len);
6995
6996 if (chan->state != BT_BOUND && chan->state != BT_CONNECTED)
6997 goto drop;
6998
6999 if (chan->imtu < skb->len)
7000 goto drop;
7001
7002 /* Store remote BD_ADDR and PSM for msg_name */
7003 bacpy(&bt_cb(skb)->l2cap.bdaddr, &hcon->dst);
7004 bt_cb(skb)->l2cap.psm = psm;
7005
7006 if (!chan->ops->recv(chan, skb)) {
7007 l2cap_chan_put(chan);
7008 return;
7009 }
7010
7011drop:
7012 l2cap_chan_put(chan);
7013free_skb:
7014 kfree_skb(skb);
7015}
7016
7017static void l2cap_recv_frame(struct l2cap_conn *conn, struct sk_buff *skb)
7018{
7019 struct l2cap_hdr *lh = (void *) skb->data;
7020 struct hci_conn *hcon = conn->hcon;
7021 u16 cid, len;
7022 __le16 psm;
7023
7024 if (hcon->state != BT_CONNECTED) {
7025 BT_DBG("queueing pending rx skb");
7026 skb_queue_tail(&conn->pending_rx, skb);
7027 return;
7028 }
7029
7030 skb_pull(skb, L2CAP_HDR_SIZE);
7031 cid = __le16_to_cpu(lh->cid);
7032 len = __le16_to_cpu(lh->len);
7033
7034 if (len != skb->len) {
7035 kfree_skb(skb);
7036 return;
7037 }
7038
7039 /* Since we can't actively block incoming LE connections we must
7040 * at least ensure that we ignore incoming data from them.
7041 */
7042 if (hcon->type == LE_LINK &&
7043 hci_bdaddr_list_lookup(&hcon->hdev->blacklist, &hcon->dst,
7044 bdaddr_dst_type(hcon))) {
7045 kfree_skb(skb);
7046 return;
7047 }
7048
7049 BT_DBG("len %d, cid 0x%4.4x", len, cid);
7050
7051 switch (cid) {
7052 case L2CAP_CID_SIGNALING:
7053 l2cap_sig_channel(conn, skb);
7054 break;
7055
7056 case L2CAP_CID_CONN_LESS:
7057 psm = get_unaligned((__le16 *) skb->data);
7058 skb_pull(skb, L2CAP_PSMLEN_SIZE);
7059 l2cap_conless_channel(conn, psm, skb);
7060 break;
7061
7062 case L2CAP_CID_LE_SIGNALING:
7063 l2cap_le_sig_channel(conn, skb);
7064 break;
7065
7066 default:
7067 l2cap_data_channel(conn, cid, skb);
7068 break;
7069 }
7070}
7071
7072static void process_pending_rx(struct work_struct *work)
7073{
7074 struct l2cap_conn *conn = container_of(work, struct l2cap_conn,
7075 pending_rx_work);
7076 struct sk_buff *skb;
7077
7078 BT_DBG("");
7079
7080 while ((skb = skb_dequeue(&conn->pending_rx)))
7081 l2cap_recv_frame(conn, skb);
7082}
7083
7084static struct l2cap_conn *l2cap_conn_add(struct hci_conn *hcon)
7085{
7086 struct l2cap_conn *conn = hcon->l2cap_data;
7087 struct hci_chan *hchan;
7088
7089 if (conn)
7090 return conn;
7091
7092 hchan = hci_chan_create(hcon);
7093 if (!hchan)
7094 return NULL;
7095
7096 conn = kzalloc(sizeof(*conn), GFP_KERNEL);
7097 if (!conn) {
7098 hci_chan_del(hchan);
7099 return NULL;
7100 }
7101
7102 kref_init(&conn->ref);
7103 hcon->l2cap_data = conn;
7104 conn->hcon = hci_conn_get(hcon);
7105 conn->hchan = hchan;
7106
7107 BT_DBG("hcon %p conn %p hchan %p", hcon, conn, hchan);
7108
7109 switch (hcon->type) {
7110 case LE_LINK:
7111 if (hcon->hdev->le_mtu) {
7112 conn->mtu = hcon->hdev->le_mtu;
7113 break;
7114 }
7115 /* fall through */
7116 default:
7117 conn->mtu = hcon->hdev->acl_mtu;
7118 break;
7119 }
7120
7121 conn->feat_mask = 0;
7122
7123 conn->local_fixed_chan = L2CAP_FC_SIG_BREDR | L2CAP_FC_CONNLESS;
7124
7125 if (hcon->type == ACL_LINK &&
7126 hci_dev_test_flag(hcon->hdev, HCI_HS_ENABLED))
7127 conn->local_fixed_chan |= L2CAP_FC_A2MP;
7128
7129 if (hci_dev_test_flag(hcon->hdev, HCI_LE_ENABLED) &&
7130 (bredr_sc_enabled(hcon->hdev) ||
7131 hci_dev_test_flag(hcon->hdev, HCI_FORCE_BREDR_SMP)))
7132 conn->local_fixed_chan |= L2CAP_FC_SMP_BREDR;
7133
7134 mutex_init(&conn->ident_lock);
7135 mutex_init(&conn->chan_lock);
7136
7137 INIT_LIST_HEAD(&conn->chan_l);
7138 INIT_LIST_HEAD(&conn->users);
7139
7140 INIT_DELAYED_WORK(&conn->info_timer, l2cap_info_timeout);
7141
7142 skb_queue_head_init(&conn->pending_rx);
7143 INIT_WORK(&conn->pending_rx_work, process_pending_rx);
7144 INIT_WORK(&conn->id_addr_update_work, l2cap_conn_update_id_addr);
7145
7146 conn->disc_reason = HCI_ERROR_REMOTE_USER_TERM;
7147
7148 return conn;
7149}
7150
7151static bool is_valid_psm(u16 psm, u8 dst_type) {
7152 if (!psm)
7153 return false;
7154
7155 if (bdaddr_type_is_le(dst_type))
7156 return (psm <= 0x00ff);
7157
7158 /* PSM must be odd and lsb of upper byte must be 0 */
7159 return ((psm & 0x0101) == 0x0001);
7160}
7161
7162int l2cap_chan_connect(struct l2cap_chan *chan, __le16 psm, u16 cid,
7163 bdaddr_t *dst, u8 dst_type)
7164{
7165 struct l2cap_conn *conn;
7166 struct hci_conn *hcon;
7167 struct hci_dev *hdev;
7168 int err;
7169
7170 BT_DBG("%pMR -> %pMR (type %u) psm 0x%2.2x", &chan->src, dst,
7171 dst_type, __le16_to_cpu(psm));
7172
7173 hdev = hci_get_route(dst, &chan->src, chan->src_type);
7174 if (!hdev)
7175 return -EHOSTUNREACH;
7176
7177 hci_dev_lock(hdev);
7178
7179 if (!is_valid_psm(__le16_to_cpu(psm), dst_type) && !cid &&
7180 chan->chan_type != L2CAP_CHAN_RAW) {
7181 err = -EINVAL;
7182 goto done;
7183 }
7184
7185 if (chan->chan_type == L2CAP_CHAN_CONN_ORIENTED && !psm) {
7186 err = -EINVAL;
7187 goto done;
7188 }
7189
7190 if (chan->chan_type == L2CAP_CHAN_FIXED && !cid) {
7191 err = -EINVAL;
7192 goto done;
7193 }
7194
7195 switch (chan->mode) {
7196 case L2CAP_MODE_BASIC:
7197 break;
7198 case L2CAP_MODE_LE_FLOWCTL:
7199 break;
7200 case L2CAP_MODE_ERTM:
7201 case L2CAP_MODE_STREAMING:
7202 if (!disable_ertm)
7203 break;
7204 /* fall through */
7205 default:
7206 err = -EOPNOTSUPP;
7207 goto done;
7208 }
7209
7210 switch (chan->state) {
7211 case BT_CONNECT:
7212 case BT_CONNECT2:
7213 case BT_CONFIG:
7214 /* Already connecting */
7215 err = 0;
7216 goto done;
7217
7218 case BT_CONNECTED:
7219 /* Already connected */
7220 err = -EISCONN;
7221 goto done;
7222
7223 case BT_OPEN:
7224 case BT_BOUND:
7225 /* Can connect */
7226 break;
7227
7228 default:
7229 err = -EBADFD;
7230 goto done;
7231 }
7232
7233 /* Set destination address and psm */
7234 bacpy(&chan->dst, dst);
7235 chan->dst_type = dst_type;
7236
7237 chan->psm = psm;
7238 chan->dcid = cid;
7239
7240 if (bdaddr_type_is_le(dst_type)) {
7241 /* Convert from L2CAP channel address type to HCI address type
7242 */
7243 if (dst_type == BDADDR_LE_PUBLIC)
7244 dst_type = ADDR_LE_DEV_PUBLIC;
7245 else
7246 dst_type = ADDR_LE_DEV_RANDOM;
7247
7248 if (hci_dev_test_flag(hdev, HCI_ADVERTISING))
7249 hcon = hci_connect_le(hdev, dst, dst_type,
7250 chan->sec_level,
7251 HCI_LE_CONN_TIMEOUT,
7252 HCI_ROLE_SLAVE, NULL);
7253 else
7254 hcon = hci_connect_le_scan(hdev, dst, dst_type,
7255 chan->sec_level,
7256 HCI_LE_CONN_TIMEOUT);
7257
7258 } else {
7259 u8 auth_type = l2cap_get_auth_type(chan);
7260 hcon = hci_connect_acl(hdev, dst, chan->sec_level, auth_type);
7261 }
7262
7263 if (IS_ERR(hcon)) {
7264 err = PTR_ERR(hcon);
7265 goto done;
7266 }
7267
7268 conn = l2cap_conn_add(hcon);
7269 if (!conn) {
7270 hci_conn_drop(hcon);
7271 err = -ENOMEM;
7272 goto done;
7273 }
7274
7275 mutex_lock(&conn->chan_lock);
7276 l2cap_chan_lock(chan);
7277
7278 if (cid && __l2cap_get_chan_by_dcid(conn, cid)) {
7279 hci_conn_drop(hcon);
7280 err = -EBUSY;
7281 goto chan_unlock;
7282 }
7283
7284 /* Update source addr of the socket */
7285 bacpy(&chan->src, &hcon->src);
7286 chan->src_type = bdaddr_src_type(hcon);
7287
7288 __l2cap_chan_add(conn, chan);
7289
7290 /* l2cap_chan_add takes its own ref so we can drop this one */
7291 hci_conn_drop(hcon);
7292
7293 l2cap_state_change(chan, BT_CONNECT);
7294 __set_chan_timer(chan, chan->ops->get_sndtimeo(chan));
7295
7296 /* Release chan->sport so that it can be reused by other
7297 * sockets (as it's only used for listening sockets).
7298 */
7299 write_lock(&chan_list_lock);
7300 chan->sport = 0;
7301 write_unlock(&chan_list_lock);
7302
7303 if (hcon->state == BT_CONNECTED) {
7304 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) {
7305 __clear_chan_timer(chan);
7306 if (l2cap_chan_check_security(chan, true))
7307 l2cap_state_change(chan, BT_CONNECTED);
7308 } else
7309 l2cap_do_start(chan);
7310 }
7311
7312 err = 0;
7313
7314chan_unlock:
7315 l2cap_chan_unlock(chan);
7316 mutex_unlock(&conn->chan_lock);
7317done:
7318 hci_dev_unlock(hdev);
7319 hci_dev_put(hdev);
7320 return err;
7321}
7322EXPORT_SYMBOL_GPL(l2cap_chan_connect);
7323
7324/* ---- L2CAP interface with lower layer (HCI) ---- */
7325
7326int l2cap_connect_ind(struct hci_dev *hdev, bdaddr_t *bdaddr)
7327{
7328 int exact = 0, lm1 = 0, lm2 = 0;
7329 struct l2cap_chan *c;
7330
7331 BT_DBG("hdev %s, bdaddr %pMR", hdev->name, bdaddr);
7332
7333 /* Find listening sockets and check their link_mode */
7334 read_lock(&chan_list_lock);
7335 list_for_each_entry(c, &chan_list, global_l) {
7336 if (c->state != BT_LISTEN)
7337 continue;
7338
7339 if (!bacmp(&c->src, &hdev->bdaddr)) {
7340 lm1 |= HCI_LM_ACCEPT;
7341 if (test_bit(FLAG_ROLE_SWITCH, &c->flags))
7342 lm1 |= HCI_LM_MASTER;
7343 exact++;
7344 } else if (!bacmp(&c->src, BDADDR_ANY)) {
7345 lm2 |= HCI_LM_ACCEPT;
7346 if (test_bit(FLAG_ROLE_SWITCH, &c->flags))
7347 lm2 |= HCI_LM_MASTER;
7348 }
7349 }
7350 read_unlock(&chan_list_lock);
7351
7352 return exact ? lm1 : lm2;
7353}
7354
7355/* Find the next fixed channel in BT_LISTEN state, continue iteration
7356 * from an existing channel in the list or from the beginning of the
7357 * global list (by passing NULL as first parameter).
7358 */
7359static struct l2cap_chan *l2cap_global_fixed_chan(struct l2cap_chan *c,
7360 struct hci_conn *hcon)
7361{
7362 u8 src_type = bdaddr_src_type(hcon);
7363
7364 read_lock(&chan_list_lock);
7365
7366 if (c)
7367 c = list_next_entry(c, global_l);
7368 else
7369 c = list_entry(chan_list.next, typeof(*c), global_l);
7370
7371 list_for_each_entry_from(c, &chan_list, global_l) {
7372 if (c->chan_type != L2CAP_CHAN_FIXED)
7373 continue;
7374 if (c->state != BT_LISTEN)
7375 continue;
7376 if (bacmp(&c->src, &hcon->src) && bacmp(&c->src, BDADDR_ANY))
7377 continue;
7378 if (src_type != c->src_type)
7379 continue;
7380
7381 l2cap_chan_hold(c);
7382 read_unlock(&chan_list_lock);
7383 return c;
7384 }
7385
7386 read_unlock(&chan_list_lock);
7387
7388 return NULL;
7389}
7390
7391static void l2cap_connect_cfm(struct hci_conn *hcon, u8 status)
7392{
7393 struct hci_dev *hdev = hcon->hdev;
7394 struct l2cap_conn *conn;
7395 struct l2cap_chan *pchan;
7396 u8 dst_type;
7397
7398 if (hcon->type != ACL_LINK && hcon->type != LE_LINK)
7399 return;
7400
7401 BT_DBG("hcon %p bdaddr %pMR status %d", hcon, &hcon->dst, status);
7402
7403 if (status) {
7404 l2cap_conn_del(hcon, bt_to_errno(status));
7405 return;
7406 }
7407
7408 conn = l2cap_conn_add(hcon);
7409 if (!conn)
7410 return;
7411
7412 dst_type = bdaddr_dst_type(hcon);
7413
7414 /* If device is blocked, do not create channels for it */
7415 if (hci_bdaddr_list_lookup(&hdev->blacklist, &hcon->dst, dst_type))
7416 return;
7417
7418 /* Find fixed channels and notify them of the new connection. We
7419 * use multiple individual lookups, continuing each time where
7420 * we left off, because the list lock would prevent calling the
7421 * potentially sleeping l2cap_chan_lock() function.
7422 */
7423 pchan = l2cap_global_fixed_chan(NULL, hcon);
7424 while (pchan) {
7425 struct l2cap_chan *chan, *next;
7426
7427 /* Client fixed channels should override server ones */
7428 if (__l2cap_get_chan_by_dcid(conn, pchan->scid))
7429 goto next;
7430
7431 l2cap_chan_lock(pchan);
7432 chan = pchan->ops->new_connection(pchan);
7433 if (chan) {
7434 bacpy(&chan->src, &hcon->src);
7435 bacpy(&chan->dst, &hcon->dst);
7436 chan->src_type = bdaddr_src_type(hcon);
7437 chan->dst_type = dst_type;
7438
7439 __l2cap_chan_add(conn, chan);
7440 }
7441
7442 l2cap_chan_unlock(pchan);
7443next:
7444 next = l2cap_global_fixed_chan(pchan, hcon);
7445 l2cap_chan_put(pchan);
7446 pchan = next;
7447 }
7448
7449 l2cap_conn_ready(conn);
7450}
7451
7452int l2cap_disconn_ind(struct hci_conn *hcon)
7453{
7454 struct l2cap_conn *conn = hcon->l2cap_data;
7455
7456 BT_DBG("hcon %p", hcon);
7457
7458 if (!conn)
7459 return HCI_ERROR_REMOTE_USER_TERM;
7460 return conn->disc_reason;
7461}
7462
7463static void l2cap_disconn_cfm(struct hci_conn *hcon, u8 reason)
7464{
7465 if (hcon->type != ACL_LINK && hcon->type != LE_LINK)
7466 return;
7467
7468 BT_DBG("hcon %p reason %d", hcon, reason);
7469
7470 l2cap_conn_del(hcon, bt_to_errno(reason));
7471}
7472
7473static inline void l2cap_check_encryption(struct l2cap_chan *chan, u8 encrypt)
7474{
7475 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED)
7476 return;
7477
7478 if (encrypt == 0x00) {
7479 if (chan->sec_level == BT_SECURITY_MEDIUM) {
7480 __set_chan_timer(chan, L2CAP_ENC_TIMEOUT);
7481 } else if (chan->sec_level == BT_SECURITY_HIGH ||
7482 chan->sec_level == BT_SECURITY_FIPS)
7483 l2cap_chan_close(chan, ECONNREFUSED);
7484 } else {
7485 if (chan->sec_level == BT_SECURITY_MEDIUM)
7486 __clear_chan_timer(chan);
7487 }
7488}
7489
7490static void l2cap_security_cfm(struct hci_conn *hcon, u8 status, u8 encrypt)
7491{
7492 struct l2cap_conn *conn = hcon->l2cap_data;
7493 struct l2cap_chan *chan;
7494
7495 if (!conn)
7496 return;
7497
7498 BT_DBG("conn %p status 0x%2.2x encrypt %u", conn, status, encrypt);
7499
7500 mutex_lock(&conn->chan_lock);
7501
7502 list_for_each_entry(chan, &conn->chan_l, list) {
7503 l2cap_chan_lock(chan);
7504
7505 BT_DBG("chan %p scid 0x%4.4x state %s", chan, chan->scid,
7506 state_to_string(chan->state));
7507
7508 if (chan->scid == L2CAP_CID_A2MP) {
7509 l2cap_chan_unlock(chan);
7510 continue;
7511 }
7512
7513 if (!status && encrypt)
7514 chan->sec_level = hcon->sec_level;
7515
7516 if (!__l2cap_no_conn_pending(chan)) {
7517 l2cap_chan_unlock(chan);
7518 continue;
7519 }
7520
7521 if (!status && (chan->state == BT_CONNECTED ||
7522 chan->state == BT_CONFIG)) {
7523 chan->ops->resume(chan);
7524 l2cap_check_encryption(chan, encrypt);
7525 l2cap_chan_unlock(chan);
7526 continue;
7527 }
7528
7529 if (chan->state == BT_CONNECT) {
7530 if (!status && l2cap_check_enc_key_size(hcon))
7531 l2cap_start_connection(chan);
7532 else
7533 __set_chan_timer(chan, L2CAP_DISC_TIMEOUT);
7534 } else if (chan->state == BT_CONNECT2 &&
7535 chan->mode != L2CAP_MODE_LE_FLOWCTL) {
7536 struct l2cap_conn_rsp rsp;
7537 __u16 res, stat;
7538
7539 if (!status && l2cap_check_enc_key_size(hcon)) {
7540 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) {
7541 res = L2CAP_CR_PEND;
7542 stat = L2CAP_CS_AUTHOR_PEND;
7543 chan->ops->defer(chan);
7544 } else {
7545 l2cap_state_change(chan, BT_CONFIG);
7546 res = L2CAP_CR_SUCCESS;
7547 stat = L2CAP_CS_NO_INFO;
7548 }
7549 } else {
7550 l2cap_state_change(chan, BT_DISCONN);
7551 __set_chan_timer(chan, L2CAP_DISC_TIMEOUT);
7552 res = L2CAP_CR_SEC_BLOCK;
7553 stat = L2CAP_CS_NO_INFO;
7554 }
7555
7556 rsp.scid = cpu_to_le16(chan->dcid);
7557 rsp.dcid = cpu_to_le16(chan->scid);
7558 rsp.result = cpu_to_le16(res);
7559 rsp.status = cpu_to_le16(stat);
7560 l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_RSP,
7561 sizeof(rsp), &rsp);
7562
7563 if (!test_bit(CONF_REQ_SENT, &chan->conf_state) &&
7564 res == L2CAP_CR_SUCCESS) {
7565 char buf[128];
7566 set_bit(CONF_REQ_SENT, &chan->conf_state);
7567 l2cap_send_cmd(conn, l2cap_get_ident(conn),
7568 L2CAP_CONF_REQ,
7569 l2cap_build_conf_req(chan, buf, sizeof(buf)),
7570 buf);
7571 chan->num_conf_req++;
7572 }
7573 }
7574
7575 l2cap_chan_unlock(chan);
7576 }
7577
7578 mutex_unlock(&conn->chan_lock);
7579}
7580
7581void l2cap_recv_acldata(struct hci_conn *hcon, struct sk_buff *skb, u16 flags)
7582{
7583 struct l2cap_conn *conn = hcon->l2cap_data;
7584 struct l2cap_hdr *hdr;
7585 int len;
7586
7587 /* For AMP controller do not create l2cap conn */
7588 if (!conn && hcon->hdev->dev_type != HCI_PRIMARY)
7589 goto drop;
7590
7591 if (!conn)
7592 conn = l2cap_conn_add(hcon);
7593
7594 if (!conn)
7595 goto drop;
7596
7597 BT_DBG("conn %p len %d flags 0x%x", conn, skb->len, flags);
7598
7599 switch (flags) {
7600 case ACL_START:
7601 case ACL_START_NO_FLUSH:
7602 case ACL_COMPLETE:
7603 if (conn->rx_len) {
7604 BT_ERR("Unexpected start frame (len %d)", skb->len);
7605 kfree_skb(conn->rx_skb);
7606 conn->rx_skb = NULL;
7607 conn->rx_len = 0;
7608 l2cap_conn_unreliable(conn, ECOMM);
7609 }
7610
7611 /* Start fragment always begin with Basic L2CAP header */
7612 if (skb->len < L2CAP_HDR_SIZE) {
7613 BT_ERR("Frame is too short (len %d)", skb->len);
7614 l2cap_conn_unreliable(conn, ECOMM);
7615 goto drop;
7616 }
7617
7618 hdr = (struct l2cap_hdr *) skb->data;
7619 len = __le16_to_cpu(hdr->len) + L2CAP_HDR_SIZE;
7620
7621 if (len == skb->len) {
7622 /* Complete frame received */
7623 l2cap_recv_frame(conn, skb);
7624 return;
7625 }
7626
7627 BT_DBG("Start: total len %d, frag len %d", len, skb->len);
7628
7629 if (skb->len > len) {
7630 BT_ERR("Frame is too long (len %d, expected len %d)",
7631 skb->len, len);
7632 l2cap_conn_unreliable(conn, ECOMM);
7633 goto drop;
7634 }
7635
7636 /* Allocate skb for the complete frame (with header) */
7637 conn->rx_skb = bt_skb_alloc(len, GFP_KERNEL);
7638 if (!conn->rx_skb)
7639 goto drop;
7640
7641 skb_copy_from_linear_data(skb, skb_put(conn->rx_skb, skb->len),
7642 skb->len);
7643 conn->rx_len = len - skb->len;
7644 break;
7645
7646 case ACL_CONT:
7647 BT_DBG("Cont: frag len %d (expecting %d)", skb->len, conn->rx_len);
7648
7649 if (!conn->rx_len) {
7650 BT_ERR("Unexpected continuation frame (len %d)", skb->len);
7651 l2cap_conn_unreliable(conn, ECOMM);
7652 goto drop;
7653 }
7654
7655 if (skb->len > conn->rx_len) {
7656 BT_ERR("Fragment is too long (len %d, expected %d)",
7657 skb->len, conn->rx_len);
7658 kfree_skb(conn->rx_skb);
7659 conn->rx_skb = NULL;
7660 conn->rx_len = 0;
7661 l2cap_conn_unreliable(conn, ECOMM);
7662 goto drop;
7663 }
7664
7665 skb_copy_from_linear_data(skb, skb_put(conn->rx_skb, skb->len),
7666 skb->len);
7667 conn->rx_len -= skb->len;
7668
7669 if (!conn->rx_len) {
7670 /* Complete frame received. l2cap_recv_frame
7671 * takes ownership of the skb so set the global
7672 * rx_skb pointer to NULL first.
7673 */
7674 struct sk_buff *rx_skb = conn->rx_skb;
7675 conn->rx_skb = NULL;
7676 l2cap_recv_frame(conn, rx_skb);
7677 }
7678 break;
7679 }
7680
7681drop:
7682 kfree_skb(skb);
7683}
7684
7685static struct hci_cb l2cap_cb = {
7686 .name = "L2CAP",
7687 .connect_cfm = l2cap_connect_cfm,
7688 .disconn_cfm = l2cap_disconn_cfm,
7689 .security_cfm = l2cap_security_cfm,
7690};
7691
7692static int l2cap_debugfs_show(struct seq_file *f, void *p)
7693{
7694 struct l2cap_chan *c;
7695
7696 read_lock(&chan_list_lock);
7697
7698 list_for_each_entry(c, &chan_list, global_l) {
7699 seq_printf(f, "%pMR (%u) %pMR (%u) %d %d 0x%4.4x 0x%4.4x %d %d %d %d\n",
7700 &c->src, c->src_type, &c->dst, c->dst_type,
7701 c->state, __le16_to_cpu(c->psm),
7702 c->scid, c->dcid, c->imtu, c->omtu,
7703 c->sec_level, c->mode);
7704 }
7705
7706 read_unlock(&chan_list_lock);
7707
7708 return 0;
7709}
7710
7711DEFINE_SHOW_ATTRIBUTE(l2cap_debugfs);
7712
7713static struct dentry *l2cap_debugfs;
7714
7715int __init l2cap_init(void)
7716{
7717 int err;
7718
7719 err = l2cap_init_sockets();
7720 if (err < 0)
7721 return err;
7722
7723 hci_register_cb(&l2cap_cb);
7724
7725 if (IS_ERR_OR_NULL(bt_debugfs))
7726 return 0;
7727
7728 l2cap_debugfs = debugfs_create_file("l2cap", 0444, bt_debugfs,
7729 NULL, &l2cap_debugfs_fops);
7730
7731 return 0;
7732}
7733
7734void l2cap_exit(void)
7735{
7736 debugfs_remove(l2cap_debugfs);
7737 hci_unregister_cb(&l2cap_cb);
7738 l2cap_cleanup_sockets();
7739}
7740
7741module_param(disable_ertm, bool, 0644);
7742MODULE_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 = IS_ENABLED(CONFIG_BT_LE_L2CAP_ECRED);
49
50static u32 l2cap_feat_mask = L2CAP_FEAT_FIXED_CHAN | L2CAP_FEAT_UCD;
51
52static LIST_HEAD(chan_list);
53static DEFINE_RWLOCK(chan_list_lock);
54
55static struct sk_buff *l2cap_build_cmd(struct l2cap_conn *conn,
56 u8 code, u8 ident, u16 dlen, void *data);
57static void l2cap_send_cmd(struct l2cap_conn *conn, u8 ident, u8 code, u16 len,
58 void *data);
59static int l2cap_build_conf_req(struct l2cap_chan *chan, void *data, size_t data_size);
60static void l2cap_send_disconn_req(struct l2cap_chan *chan, int err);
61
62static void l2cap_tx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
63 struct sk_buff_head *skbs, u8 event);
64static void l2cap_retrans_timeout(struct work_struct *work);
65static void l2cap_monitor_timeout(struct work_struct *work);
66static void l2cap_ack_timeout(struct work_struct *work);
67
68static inline u8 bdaddr_type(u8 link_type, u8 bdaddr_type)
69{
70 if (link_type == LE_LINK) {
71 if (bdaddr_type == ADDR_LE_DEV_PUBLIC)
72 return BDADDR_LE_PUBLIC;
73 else
74 return BDADDR_LE_RANDOM;
75 }
76
77 return BDADDR_BREDR;
78}
79
80static inline u8 bdaddr_src_type(struct hci_conn *hcon)
81{
82 return bdaddr_type(hcon->type, hcon->src_type);
83}
84
85static inline u8 bdaddr_dst_type(struct hci_conn *hcon)
86{
87 return bdaddr_type(hcon->type, hcon->dst_type);
88}
89
90/* ---- L2CAP channels ---- */
91
92static struct l2cap_chan *__l2cap_get_chan_by_dcid(struct l2cap_conn *conn,
93 u16 cid)
94{
95 struct l2cap_chan *c;
96
97 list_for_each_entry(c, &conn->chan_l, list) {
98 if (c->dcid == cid)
99 return c;
100 }
101 return NULL;
102}
103
104static struct l2cap_chan *__l2cap_get_chan_by_scid(struct l2cap_conn *conn,
105 u16 cid)
106{
107 struct l2cap_chan *c;
108
109 list_for_each_entry(c, &conn->chan_l, list) {
110 if (c->scid == cid)
111 return c;
112 }
113 return NULL;
114}
115
116/* Find channel with given SCID.
117 * Returns a reference locked channel.
118 */
119static struct l2cap_chan *l2cap_get_chan_by_scid(struct l2cap_conn *conn,
120 u16 cid)
121{
122 struct l2cap_chan *c;
123
124 mutex_lock(&conn->chan_lock);
125 c = __l2cap_get_chan_by_scid(conn, cid);
126 if (c) {
127 /* Only lock if chan reference is not 0 */
128 c = l2cap_chan_hold_unless_zero(c);
129 if (c)
130 l2cap_chan_lock(c);
131 }
132 mutex_unlock(&conn->chan_lock);
133
134 return c;
135}
136
137/* Find channel with given DCID.
138 * Returns a reference locked channel.
139 */
140static struct l2cap_chan *l2cap_get_chan_by_dcid(struct l2cap_conn *conn,
141 u16 cid)
142{
143 struct l2cap_chan *c;
144
145 mutex_lock(&conn->chan_lock);
146 c = __l2cap_get_chan_by_dcid(conn, cid);
147 if (c) {
148 /* Only lock if chan reference is not 0 */
149 c = l2cap_chan_hold_unless_zero(c);
150 if (c)
151 l2cap_chan_lock(c);
152 }
153 mutex_unlock(&conn->chan_lock);
154
155 return c;
156}
157
158static struct l2cap_chan *__l2cap_get_chan_by_ident(struct l2cap_conn *conn,
159 u8 ident)
160{
161 struct l2cap_chan *c;
162
163 list_for_each_entry(c, &conn->chan_l, list) {
164 if (c->ident == ident)
165 return c;
166 }
167 return NULL;
168}
169
170static struct l2cap_chan *l2cap_get_chan_by_ident(struct l2cap_conn *conn,
171 u8 ident)
172{
173 struct l2cap_chan *c;
174
175 mutex_lock(&conn->chan_lock);
176 c = __l2cap_get_chan_by_ident(conn, ident);
177 if (c) {
178 /* Only lock if chan reference is not 0 */
179 c = l2cap_chan_hold_unless_zero(c);
180 if (c)
181 l2cap_chan_lock(c);
182 }
183 mutex_unlock(&conn->chan_lock);
184
185 return c;
186}
187
188static struct l2cap_chan *__l2cap_global_chan_by_addr(__le16 psm, bdaddr_t *src,
189 u8 src_type)
190{
191 struct l2cap_chan *c;
192
193 list_for_each_entry(c, &chan_list, global_l) {
194 if (src_type == BDADDR_BREDR && c->src_type != BDADDR_BREDR)
195 continue;
196
197 if (src_type != BDADDR_BREDR && c->src_type == BDADDR_BREDR)
198 continue;
199
200 if (c->sport == psm && !bacmp(&c->src, src))
201 return c;
202 }
203 return NULL;
204}
205
206int l2cap_add_psm(struct l2cap_chan *chan, bdaddr_t *src, __le16 psm)
207{
208 int err;
209
210 write_lock(&chan_list_lock);
211
212 if (psm && __l2cap_global_chan_by_addr(psm, src, chan->src_type)) {
213 err = -EADDRINUSE;
214 goto done;
215 }
216
217 if (psm) {
218 chan->psm = psm;
219 chan->sport = psm;
220 err = 0;
221 } else {
222 u16 p, start, end, incr;
223
224 if (chan->src_type == BDADDR_BREDR) {
225 start = L2CAP_PSM_DYN_START;
226 end = L2CAP_PSM_AUTO_END;
227 incr = 2;
228 } else {
229 start = L2CAP_PSM_LE_DYN_START;
230 end = L2CAP_PSM_LE_DYN_END;
231 incr = 1;
232 }
233
234 err = -EINVAL;
235 for (p = start; p <= end; p += incr)
236 if (!__l2cap_global_chan_by_addr(cpu_to_le16(p), src,
237 chan->src_type)) {
238 chan->psm = cpu_to_le16(p);
239 chan->sport = cpu_to_le16(p);
240 err = 0;
241 break;
242 }
243 }
244
245done:
246 write_unlock(&chan_list_lock);
247 return err;
248}
249EXPORT_SYMBOL_GPL(l2cap_add_psm);
250
251int l2cap_add_scid(struct l2cap_chan *chan, __u16 scid)
252{
253 write_lock(&chan_list_lock);
254
255 /* Override the defaults (which are for conn-oriented) */
256 chan->omtu = L2CAP_DEFAULT_MTU;
257 chan->chan_type = L2CAP_CHAN_FIXED;
258
259 chan->scid = scid;
260
261 write_unlock(&chan_list_lock);
262
263 return 0;
264}
265
266static u16 l2cap_alloc_cid(struct l2cap_conn *conn)
267{
268 u16 cid, dyn_end;
269
270 if (conn->hcon->type == LE_LINK)
271 dyn_end = L2CAP_CID_LE_DYN_END;
272 else
273 dyn_end = L2CAP_CID_DYN_END;
274
275 for (cid = L2CAP_CID_DYN_START; cid <= dyn_end; cid++) {
276 if (!__l2cap_get_chan_by_scid(conn, cid))
277 return cid;
278 }
279
280 return 0;
281}
282
283static void l2cap_state_change(struct l2cap_chan *chan, int state)
284{
285 BT_DBG("chan %p %s -> %s", chan, state_to_string(chan->state),
286 state_to_string(state));
287
288 chan->state = state;
289 chan->ops->state_change(chan, state, 0);
290}
291
292static inline void l2cap_state_change_and_error(struct l2cap_chan *chan,
293 int state, int err)
294{
295 chan->state = state;
296 chan->ops->state_change(chan, chan->state, err);
297}
298
299static inline void l2cap_chan_set_err(struct l2cap_chan *chan, int err)
300{
301 chan->ops->state_change(chan, chan->state, err);
302}
303
304static void __set_retrans_timer(struct l2cap_chan *chan)
305{
306 if (!delayed_work_pending(&chan->monitor_timer) &&
307 chan->retrans_timeout) {
308 l2cap_set_timer(chan, &chan->retrans_timer,
309 msecs_to_jiffies(chan->retrans_timeout));
310 }
311}
312
313static void __set_monitor_timer(struct l2cap_chan *chan)
314{
315 __clear_retrans_timer(chan);
316 if (chan->monitor_timeout) {
317 l2cap_set_timer(chan, &chan->monitor_timer,
318 msecs_to_jiffies(chan->monitor_timeout));
319 }
320}
321
322static struct sk_buff *l2cap_ertm_seq_in_queue(struct sk_buff_head *head,
323 u16 seq)
324{
325 struct sk_buff *skb;
326
327 skb_queue_walk(head, skb) {
328 if (bt_cb(skb)->l2cap.txseq == seq)
329 return skb;
330 }
331
332 return NULL;
333}
334
335/* ---- L2CAP sequence number lists ---- */
336
337/* For ERTM, ordered lists of sequence numbers must be tracked for
338 * SREJ requests that are received and for frames that are to be
339 * retransmitted. These seq_list functions implement a singly-linked
340 * list in an array, where membership in the list can also be checked
341 * in constant time. Items can also be added to the tail of the list
342 * and removed from the head in constant time, without further memory
343 * allocs or frees.
344 */
345
346static int l2cap_seq_list_init(struct l2cap_seq_list *seq_list, u16 size)
347{
348 size_t alloc_size, i;
349
350 /* Allocated size is a power of 2 to map sequence numbers
351 * (which may be up to 14 bits) in to a smaller array that is
352 * sized for the negotiated ERTM transmit windows.
353 */
354 alloc_size = roundup_pow_of_two(size);
355
356 seq_list->list = kmalloc_array(alloc_size, sizeof(u16), GFP_KERNEL);
357 if (!seq_list->list)
358 return -ENOMEM;
359
360 seq_list->mask = alloc_size - 1;
361 seq_list->head = L2CAP_SEQ_LIST_CLEAR;
362 seq_list->tail = L2CAP_SEQ_LIST_CLEAR;
363 for (i = 0; i < alloc_size; i++)
364 seq_list->list[i] = L2CAP_SEQ_LIST_CLEAR;
365
366 return 0;
367}
368
369static inline void l2cap_seq_list_free(struct l2cap_seq_list *seq_list)
370{
371 kfree(seq_list->list);
372}
373
374static inline bool l2cap_seq_list_contains(struct l2cap_seq_list *seq_list,
375 u16 seq)
376{
377 /* Constant-time check for list membership */
378 return seq_list->list[seq & seq_list->mask] != L2CAP_SEQ_LIST_CLEAR;
379}
380
381static inline u16 l2cap_seq_list_pop(struct l2cap_seq_list *seq_list)
382{
383 u16 seq = seq_list->head;
384 u16 mask = seq_list->mask;
385
386 seq_list->head = seq_list->list[seq & mask];
387 seq_list->list[seq & mask] = L2CAP_SEQ_LIST_CLEAR;
388
389 if (seq_list->head == L2CAP_SEQ_LIST_TAIL) {
390 seq_list->head = L2CAP_SEQ_LIST_CLEAR;
391 seq_list->tail = L2CAP_SEQ_LIST_CLEAR;
392 }
393
394 return seq;
395}
396
397static void l2cap_seq_list_clear(struct l2cap_seq_list *seq_list)
398{
399 u16 i;
400
401 if (seq_list->head == L2CAP_SEQ_LIST_CLEAR)
402 return;
403
404 for (i = 0; i <= seq_list->mask; i++)
405 seq_list->list[i] = L2CAP_SEQ_LIST_CLEAR;
406
407 seq_list->head = L2CAP_SEQ_LIST_CLEAR;
408 seq_list->tail = L2CAP_SEQ_LIST_CLEAR;
409}
410
411static void l2cap_seq_list_append(struct l2cap_seq_list *seq_list, u16 seq)
412{
413 u16 mask = seq_list->mask;
414
415 /* All appends happen in constant time */
416
417 if (seq_list->list[seq & mask] != L2CAP_SEQ_LIST_CLEAR)
418 return;
419
420 if (seq_list->tail == L2CAP_SEQ_LIST_CLEAR)
421 seq_list->head = seq;
422 else
423 seq_list->list[seq_list->tail & mask] = seq;
424
425 seq_list->tail = seq;
426 seq_list->list[seq & mask] = L2CAP_SEQ_LIST_TAIL;
427}
428
429static void l2cap_chan_timeout(struct work_struct *work)
430{
431 struct l2cap_chan *chan = container_of(work, struct l2cap_chan,
432 chan_timer.work);
433 struct l2cap_conn *conn = chan->conn;
434 int reason;
435
436 BT_DBG("chan %p state %s", chan, state_to_string(chan->state));
437
438 mutex_lock(&conn->chan_lock);
439 /* __set_chan_timer() calls l2cap_chan_hold(chan) while scheduling
440 * this work. No need to call l2cap_chan_hold(chan) here again.
441 */
442 l2cap_chan_lock(chan);
443
444 if (chan->state == BT_CONNECTED || chan->state == BT_CONFIG)
445 reason = ECONNREFUSED;
446 else if (chan->state == BT_CONNECT &&
447 chan->sec_level != BT_SECURITY_SDP)
448 reason = ECONNREFUSED;
449 else
450 reason = ETIMEDOUT;
451
452 l2cap_chan_close(chan, reason);
453
454 chan->ops->close(chan);
455
456 l2cap_chan_unlock(chan);
457 l2cap_chan_put(chan);
458
459 mutex_unlock(&conn->chan_lock);
460}
461
462struct l2cap_chan *l2cap_chan_create(void)
463{
464 struct l2cap_chan *chan;
465
466 chan = kzalloc(sizeof(*chan), GFP_ATOMIC);
467 if (!chan)
468 return NULL;
469
470 skb_queue_head_init(&chan->tx_q);
471 skb_queue_head_init(&chan->srej_q);
472 mutex_init(&chan->lock);
473
474 /* Set default lock nesting level */
475 atomic_set(&chan->nesting, L2CAP_NESTING_NORMAL);
476
477 write_lock(&chan_list_lock);
478 list_add(&chan->global_l, &chan_list);
479 write_unlock(&chan_list_lock);
480
481 INIT_DELAYED_WORK(&chan->chan_timer, l2cap_chan_timeout);
482 INIT_DELAYED_WORK(&chan->retrans_timer, l2cap_retrans_timeout);
483 INIT_DELAYED_WORK(&chan->monitor_timer, l2cap_monitor_timeout);
484 INIT_DELAYED_WORK(&chan->ack_timer, l2cap_ack_timeout);
485
486 chan->state = BT_OPEN;
487
488 kref_init(&chan->kref);
489
490 /* This flag is cleared in l2cap_chan_ready() */
491 set_bit(CONF_NOT_COMPLETE, &chan->conf_state);
492
493 BT_DBG("chan %p", chan);
494
495 return chan;
496}
497EXPORT_SYMBOL_GPL(l2cap_chan_create);
498
499static void l2cap_chan_destroy(struct kref *kref)
500{
501 struct l2cap_chan *chan = container_of(kref, struct l2cap_chan, kref);
502
503 BT_DBG("chan %p", chan);
504
505 write_lock(&chan_list_lock);
506 list_del(&chan->global_l);
507 write_unlock(&chan_list_lock);
508
509 kfree(chan);
510}
511
512void l2cap_chan_hold(struct l2cap_chan *c)
513{
514 BT_DBG("chan %p orig refcnt %u", c, kref_read(&c->kref));
515
516 kref_get(&c->kref);
517}
518
519struct l2cap_chan *l2cap_chan_hold_unless_zero(struct l2cap_chan *c)
520{
521 BT_DBG("chan %p orig refcnt %u", c, kref_read(&c->kref));
522
523 if (!kref_get_unless_zero(&c->kref))
524 return NULL;
525
526 return c;
527}
528
529void l2cap_chan_put(struct l2cap_chan *c)
530{
531 BT_DBG("chan %p orig refcnt %u", c, kref_read(&c->kref));
532
533 kref_put(&c->kref, l2cap_chan_destroy);
534}
535EXPORT_SYMBOL_GPL(l2cap_chan_put);
536
537void l2cap_chan_set_defaults(struct l2cap_chan *chan)
538{
539 chan->fcs = L2CAP_FCS_CRC16;
540 chan->max_tx = L2CAP_DEFAULT_MAX_TX;
541 chan->tx_win = L2CAP_DEFAULT_TX_WINDOW;
542 chan->tx_win_max = L2CAP_DEFAULT_TX_WINDOW;
543 chan->remote_max_tx = chan->max_tx;
544 chan->remote_tx_win = chan->tx_win;
545 chan->ack_win = L2CAP_DEFAULT_TX_WINDOW;
546 chan->sec_level = BT_SECURITY_LOW;
547 chan->flush_to = L2CAP_DEFAULT_FLUSH_TO;
548 chan->retrans_timeout = L2CAP_DEFAULT_RETRANS_TO;
549 chan->monitor_timeout = L2CAP_DEFAULT_MONITOR_TO;
550
551 chan->conf_state = 0;
552 set_bit(CONF_NOT_COMPLETE, &chan->conf_state);
553
554 set_bit(FLAG_FORCE_ACTIVE, &chan->flags);
555}
556EXPORT_SYMBOL_GPL(l2cap_chan_set_defaults);
557
558static void l2cap_le_flowctl_init(struct l2cap_chan *chan, u16 tx_credits)
559{
560 chan->sdu = NULL;
561 chan->sdu_last_frag = NULL;
562 chan->sdu_len = 0;
563 chan->tx_credits = tx_credits;
564 /* Derive MPS from connection MTU to stop HCI fragmentation */
565 chan->mps = min_t(u16, chan->imtu, chan->conn->mtu - L2CAP_HDR_SIZE);
566 /* Give enough credits for a full packet */
567 chan->rx_credits = (chan->imtu / chan->mps) + 1;
568
569 skb_queue_head_init(&chan->tx_q);
570}
571
572static void l2cap_ecred_init(struct l2cap_chan *chan, u16 tx_credits)
573{
574 l2cap_le_flowctl_init(chan, tx_credits);
575
576 /* L2CAP implementations shall support a minimum MPS of 64 octets */
577 if (chan->mps < L2CAP_ECRED_MIN_MPS) {
578 chan->mps = L2CAP_ECRED_MIN_MPS;
579 chan->rx_credits = (chan->imtu / chan->mps) + 1;
580 }
581}
582
583void __l2cap_chan_add(struct l2cap_conn *conn, struct l2cap_chan *chan)
584{
585 BT_DBG("conn %p, psm 0x%2.2x, dcid 0x%4.4x", conn,
586 __le16_to_cpu(chan->psm), chan->dcid);
587
588 conn->disc_reason = HCI_ERROR_REMOTE_USER_TERM;
589
590 chan->conn = conn;
591
592 switch (chan->chan_type) {
593 case L2CAP_CHAN_CONN_ORIENTED:
594 /* Alloc CID for connection-oriented socket */
595 chan->scid = l2cap_alloc_cid(conn);
596 if (conn->hcon->type == ACL_LINK)
597 chan->omtu = L2CAP_DEFAULT_MTU;
598 break;
599
600 case L2CAP_CHAN_CONN_LESS:
601 /* Connectionless socket */
602 chan->scid = L2CAP_CID_CONN_LESS;
603 chan->dcid = L2CAP_CID_CONN_LESS;
604 chan->omtu = L2CAP_DEFAULT_MTU;
605 break;
606
607 case L2CAP_CHAN_FIXED:
608 /* Caller will set CID and CID specific MTU values */
609 break;
610
611 default:
612 /* Raw socket can send/recv signalling messages only */
613 chan->scid = L2CAP_CID_SIGNALING;
614 chan->dcid = L2CAP_CID_SIGNALING;
615 chan->omtu = L2CAP_DEFAULT_MTU;
616 }
617
618 chan->local_id = L2CAP_BESTEFFORT_ID;
619 chan->local_stype = L2CAP_SERV_BESTEFFORT;
620 chan->local_msdu = L2CAP_DEFAULT_MAX_SDU_SIZE;
621 chan->local_sdu_itime = L2CAP_DEFAULT_SDU_ITIME;
622 chan->local_acc_lat = L2CAP_DEFAULT_ACC_LAT;
623 chan->local_flush_to = L2CAP_EFS_DEFAULT_FLUSH_TO;
624
625 l2cap_chan_hold(chan);
626
627 /* Only keep a reference for fixed channels if they requested it */
628 if (chan->chan_type != L2CAP_CHAN_FIXED ||
629 test_bit(FLAG_HOLD_HCI_CONN, &chan->flags))
630 hci_conn_hold(conn->hcon);
631
632 list_add(&chan->list, &conn->chan_l);
633}
634
635void l2cap_chan_add(struct l2cap_conn *conn, struct l2cap_chan *chan)
636{
637 mutex_lock(&conn->chan_lock);
638 __l2cap_chan_add(conn, chan);
639 mutex_unlock(&conn->chan_lock);
640}
641
642void l2cap_chan_del(struct l2cap_chan *chan, int err)
643{
644 struct l2cap_conn *conn = chan->conn;
645
646 __clear_chan_timer(chan);
647
648 BT_DBG("chan %p, conn %p, err %d, state %s", chan, conn, err,
649 state_to_string(chan->state));
650
651 chan->ops->teardown(chan, err);
652
653 if (conn) {
654 struct amp_mgr *mgr = conn->hcon->amp_mgr;
655 /* Delete from channel list */
656 list_del(&chan->list);
657
658 l2cap_chan_put(chan);
659
660 chan->conn = NULL;
661
662 /* Reference was only held for non-fixed channels or
663 * fixed channels that explicitly requested it using the
664 * FLAG_HOLD_HCI_CONN flag.
665 */
666 if (chan->chan_type != L2CAP_CHAN_FIXED ||
667 test_bit(FLAG_HOLD_HCI_CONN, &chan->flags))
668 hci_conn_drop(conn->hcon);
669
670 if (mgr && mgr->bredr_chan == chan)
671 mgr->bredr_chan = NULL;
672 }
673
674 if (chan->hs_hchan) {
675 struct hci_chan *hs_hchan = chan->hs_hchan;
676
677 BT_DBG("chan %p disconnect hs_hchan %p", chan, hs_hchan);
678 amp_disconnect_logical_link(hs_hchan);
679 }
680
681 if (test_bit(CONF_NOT_COMPLETE, &chan->conf_state))
682 return;
683
684 switch (chan->mode) {
685 case L2CAP_MODE_BASIC:
686 break;
687
688 case L2CAP_MODE_LE_FLOWCTL:
689 case L2CAP_MODE_EXT_FLOWCTL:
690 skb_queue_purge(&chan->tx_q);
691 break;
692
693 case L2CAP_MODE_ERTM:
694 __clear_retrans_timer(chan);
695 __clear_monitor_timer(chan);
696 __clear_ack_timer(chan);
697
698 skb_queue_purge(&chan->srej_q);
699
700 l2cap_seq_list_free(&chan->srej_list);
701 l2cap_seq_list_free(&chan->retrans_list);
702 fallthrough;
703
704 case L2CAP_MODE_STREAMING:
705 skb_queue_purge(&chan->tx_q);
706 break;
707 }
708}
709EXPORT_SYMBOL_GPL(l2cap_chan_del);
710
711static void __l2cap_chan_list_id(struct l2cap_conn *conn, u16 id,
712 l2cap_chan_func_t func, void *data)
713{
714 struct l2cap_chan *chan, *l;
715
716 list_for_each_entry_safe(chan, l, &conn->chan_l, list) {
717 if (chan->ident == id)
718 func(chan, data);
719 }
720}
721
722static void __l2cap_chan_list(struct l2cap_conn *conn, l2cap_chan_func_t func,
723 void *data)
724{
725 struct l2cap_chan *chan;
726
727 list_for_each_entry(chan, &conn->chan_l, list) {
728 func(chan, data);
729 }
730}
731
732void l2cap_chan_list(struct l2cap_conn *conn, l2cap_chan_func_t func,
733 void *data)
734{
735 if (!conn)
736 return;
737
738 mutex_lock(&conn->chan_lock);
739 __l2cap_chan_list(conn, func, data);
740 mutex_unlock(&conn->chan_lock);
741}
742
743EXPORT_SYMBOL_GPL(l2cap_chan_list);
744
745static void l2cap_conn_update_id_addr(struct work_struct *work)
746{
747 struct l2cap_conn *conn = container_of(work, struct l2cap_conn,
748 id_addr_timer.work);
749 struct hci_conn *hcon = conn->hcon;
750 struct l2cap_chan *chan;
751
752 mutex_lock(&conn->chan_lock);
753
754 list_for_each_entry(chan, &conn->chan_l, list) {
755 l2cap_chan_lock(chan);
756 bacpy(&chan->dst, &hcon->dst);
757 chan->dst_type = bdaddr_dst_type(hcon);
758 l2cap_chan_unlock(chan);
759 }
760
761 mutex_unlock(&conn->chan_lock);
762}
763
764static void l2cap_chan_le_connect_reject(struct l2cap_chan *chan)
765{
766 struct l2cap_conn *conn = chan->conn;
767 struct l2cap_le_conn_rsp rsp;
768 u16 result;
769
770 if (test_bit(FLAG_DEFER_SETUP, &chan->flags))
771 result = L2CAP_CR_LE_AUTHORIZATION;
772 else
773 result = L2CAP_CR_LE_BAD_PSM;
774
775 l2cap_state_change(chan, BT_DISCONN);
776
777 rsp.dcid = cpu_to_le16(chan->scid);
778 rsp.mtu = cpu_to_le16(chan->imtu);
779 rsp.mps = cpu_to_le16(chan->mps);
780 rsp.credits = cpu_to_le16(chan->rx_credits);
781 rsp.result = cpu_to_le16(result);
782
783 l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CONN_RSP, sizeof(rsp),
784 &rsp);
785}
786
787static void l2cap_chan_ecred_connect_reject(struct l2cap_chan *chan)
788{
789 l2cap_state_change(chan, BT_DISCONN);
790
791 __l2cap_ecred_conn_rsp_defer(chan);
792}
793
794static void l2cap_chan_connect_reject(struct l2cap_chan *chan)
795{
796 struct l2cap_conn *conn = chan->conn;
797 struct l2cap_conn_rsp rsp;
798 u16 result;
799
800 if (test_bit(FLAG_DEFER_SETUP, &chan->flags))
801 result = L2CAP_CR_SEC_BLOCK;
802 else
803 result = L2CAP_CR_BAD_PSM;
804
805 l2cap_state_change(chan, BT_DISCONN);
806
807 rsp.scid = cpu_to_le16(chan->dcid);
808 rsp.dcid = cpu_to_le16(chan->scid);
809 rsp.result = cpu_to_le16(result);
810 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
811
812 l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_RSP, sizeof(rsp), &rsp);
813}
814
815void l2cap_chan_close(struct l2cap_chan *chan, int reason)
816{
817 struct l2cap_conn *conn = chan->conn;
818
819 BT_DBG("chan %p state %s", chan, state_to_string(chan->state));
820
821 switch (chan->state) {
822 case BT_LISTEN:
823 chan->ops->teardown(chan, 0);
824 break;
825
826 case BT_CONNECTED:
827 case BT_CONFIG:
828 if (chan->chan_type == L2CAP_CHAN_CONN_ORIENTED) {
829 __set_chan_timer(chan, chan->ops->get_sndtimeo(chan));
830 l2cap_send_disconn_req(chan, reason);
831 } else
832 l2cap_chan_del(chan, reason);
833 break;
834
835 case BT_CONNECT2:
836 if (chan->chan_type == L2CAP_CHAN_CONN_ORIENTED) {
837 if (conn->hcon->type == ACL_LINK)
838 l2cap_chan_connect_reject(chan);
839 else if (conn->hcon->type == LE_LINK) {
840 switch (chan->mode) {
841 case L2CAP_MODE_LE_FLOWCTL:
842 l2cap_chan_le_connect_reject(chan);
843 break;
844 case L2CAP_MODE_EXT_FLOWCTL:
845 l2cap_chan_ecred_connect_reject(chan);
846 return;
847 }
848 }
849 }
850
851 l2cap_chan_del(chan, reason);
852 break;
853
854 case BT_CONNECT:
855 case BT_DISCONN:
856 l2cap_chan_del(chan, reason);
857 break;
858
859 default:
860 chan->ops->teardown(chan, 0);
861 break;
862 }
863}
864EXPORT_SYMBOL(l2cap_chan_close);
865
866static inline u8 l2cap_get_auth_type(struct l2cap_chan *chan)
867{
868 switch (chan->chan_type) {
869 case L2CAP_CHAN_RAW:
870 switch (chan->sec_level) {
871 case BT_SECURITY_HIGH:
872 case BT_SECURITY_FIPS:
873 return HCI_AT_DEDICATED_BONDING_MITM;
874 case BT_SECURITY_MEDIUM:
875 return HCI_AT_DEDICATED_BONDING;
876 default:
877 return HCI_AT_NO_BONDING;
878 }
879 break;
880 case L2CAP_CHAN_CONN_LESS:
881 if (chan->psm == cpu_to_le16(L2CAP_PSM_3DSP)) {
882 if (chan->sec_level == BT_SECURITY_LOW)
883 chan->sec_level = BT_SECURITY_SDP;
884 }
885 if (chan->sec_level == BT_SECURITY_HIGH ||
886 chan->sec_level == BT_SECURITY_FIPS)
887 return HCI_AT_NO_BONDING_MITM;
888 else
889 return HCI_AT_NO_BONDING;
890 break;
891 case L2CAP_CHAN_CONN_ORIENTED:
892 if (chan->psm == cpu_to_le16(L2CAP_PSM_SDP)) {
893 if (chan->sec_level == BT_SECURITY_LOW)
894 chan->sec_level = BT_SECURITY_SDP;
895
896 if (chan->sec_level == BT_SECURITY_HIGH ||
897 chan->sec_level == BT_SECURITY_FIPS)
898 return HCI_AT_NO_BONDING_MITM;
899 else
900 return HCI_AT_NO_BONDING;
901 }
902 fallthrough;
903
904 default:
905 switch (chan->sec_level) {
906 case BT_SECURITY_HIGH:
907 case BT_SECURITY_FIPS:
908 return HCI_AT_GENERAL_BONDING_MITM;
909 case BT_SECURITY_MEDIUM:
910 return HCI_AT_GENERAL_BONDING;
911 default:
912 return HCI_AT_NO_BONDING;
913 }
914 break;
915 }
916}
917
918/* Service level security */
919int l2cap_chan_check_security(struct l2cap_chan *chan, bool initiator)
920{
921 struct l2cap_conn *conn = chan->conn;
922 __u8 auth_type;
923
924 if (conn->hcon->type == LE_LINK)
925 return smp_conn_security(conn->hcon, chan->sec_level);
926
927 auth_type = l2cap_get_auth_type(chan);
928
929 return hci_conn_security(conn->hcon, chan->sec_level, auth_type,
930 initiator);
931}
932
933static u8 l2cap_get_ident(struct l2cap_conn *conn)
934{
935 u8 id;
936
937 /* Get next available identificator.
938 * 1 - 128 are used by kernel.
939 * 129 - 199 are reserved.
940 * 200 - 254 are used by utilities like l2ping, etc.
941 */
942
943 mutex_lock(&conn->ident_lock);
944
945 if (++conn->tx_ident > 128)
946 conn->tx_ident = 1;
947
948 id = conn->tx_ident;
949
950 mutex_unlock(&conn->ident_lock);
951
952 return id;
953}
954
955static void l2cap_send_cmd(struct l2cap_conn *conn, u8 ident, u8 code, u16 len,
956 void *data)
957{
958 struct sk_buff *skb = l2cap_build_cmd(conn, code, ident, len, data);
959 u8 flags;
960
961 BT_DBG("code 0x%2.2x", code);
962
963 if (!skb)
964 return;
965
966 /* Use NO_FLUSH if supported or we have an LE link (which does
967 * not support auto-flushing packets) */
968 if (lmp_no_flush_capable(conn->hcon->hdev) ||
969 conn->hcon->type == LE_LINK)
970 flags = ACL_START_NO_FLUSH;
971 else
972 flags = ACL_START;
973
974 bt_cb(skb)->force_active = BT_POWER_FORCE_ACTIVE_ON;
975 skb->priority = HCI_PRIO_MAX;
976
977 hci_send_acl(conn->hchan, skb, flags);
978}
979
980static bool __chan_is_moving(struct l2cap_chan *chan)
981{
982 return chan->move_state != L2CAP_MOVE_STABLE &&
983 chan->move_state != L2CAP_MOVE_WAIT_PREPARE;
984}
985
986static void l2cap_do_send(struct l2cap_chan *chan, struct sk_buff *skb)
987{
988 struct hci_conn *hcon = chan->conn->hcon;
989 u16 flags;
990
991 BT_DBG("chan %p, skb %p len %d priority %u", chan, skb, skb->len,
992 skb->priority);
993
994 if (chan->hs_hcon && !__chan_is_moving(chan)) {
995 if (chan->hs_hchan)
996 hci_send_acl(chan->hs_hchan, skb, ACL_COMPLETE);
997 else
998 kfree_skb(skb);
999
1000 return;
1001 }
1002
1003 /* Use NO_FLUSH for LE links (where this is the only option) or
1004 * if the BR/EDR link supports it and flushing has not been
1005 * explicitly requested (through FLAG_FLUSHABLE).
1006 */
1007 if (hcon->type == LE_LINK ||
1008 (!test_bit(FLAG_FLUSHABLE, &chan->flags) &&
1009 lmp_no_flush_capable(hcon->hdev)))
1010 flags = ACL_START_NO_FLUSH;
1011 else
1012 flags = ACL_START;
1013
1014 bt_cb(skb)->force_active = test_bit(FLAG_FORCE_ACTIVE, &chan->flags);
1015 hci_send_acl(chan->conn->hchan, skb, flags);
1016}
1017
1018static void __unpack_enhanced_control(u16 enh, struct l2cap_ctrl *control)
1019{
1020 control->reqseq = (enh & L2CAP_CTRL_REQSEQ) >> L2CAP_CTRL_REQSEQ_SHIFT;
1021 control->final = (enh & L2CAP_CTRL_FINAL) >> L2CAP_CTRL_FINAL_SHIFT;
1022
1023 if (enh & L2CAP_CTRL_FRAME_TYPE) {
1024 /* S-Frame */
1025 control->sframe = 1;
1026 control->poll = (enh & L2CAP_CTRL_POLL) >> L2CAP_CTRL_POLL_SHIFT;
1027 control->super = (enh & L2CAP_CTRL_SUPERVISE) >> L2CAP_CTRL_SUPER_SHIFT;
1028
1029 control->sar = 0;
1030 control->txseq = 0;
1031 } else {
1032 /* I-Frame */
1033 control->sframe = 0;
1034 control->sar = (enh & L2CAP_CTRL_SAR) >> L2CAP_CTRL_SAR_SHIFT;
1035 control->txseq = (enh & L2CAP_CTRL_TXSEQ) >> L2CAP_CTRL_TXSEQ_SHIFT;
1036
1037 control->poll = 0;
1038 control->super = 0;
1039 }
1040}
1041
1042static void __unpack_extended_control(u32 ext, struct l2cap_ctrl *control)
1043{
1044 control->reqseq = (ext & L2CAP_EXT_CTRL_REQSEQ) >> L2CAP_EXT_CTRL_REQSEQ_SHIFT;
1045 control->final = (ext & L2CAP_EXT_CTRL_FINAL) >> L2CAP_EXT_CTRL_FINAL_SHIFT;
1046
1047 if (ext & L2CAP_EXT_CTRL_FRAME_TYPE) {
1048 /* S-Frame */
1049 control->sframe = 1;
1050 control->poll = (ext & L2CAP_EXT_CTRL_POLL) >> L2CAP_EXT_CTRL_POLL_SHIFT;
1051 control->super = (ext & L2CAP_EXT_CTRL_SUPERVISE) >> L2CAP_EXT_CTRL_SUPER_SHIFT;
1052
1053 control->sar = 0;
1054 control->txseq = 0;
1055 } else {
1056 /* I-Frame */
1057 control->sframe = 0;
1058 control->sar = (ext & L2CAP_EXT_CTRL_SAR) >> L2CAP_EXT_CTRL_SAR_SHIFT;
1059 control->txseq = (ext & L2CAP_EXT_CTRL_TXSEQ) >> L2CAP_EXT_CTRL_TXSEQ_SHIFT;
1060
1061 control->poll = 0;
1062 control->super = 0;
1063 }
1064}
1065
1066static inline void __unpack_control(struct l2cap_chan *chan,
1067 struct sk_buff *skb)
1068{
1069 if (test_bit(FLAG_EXT_CTRL, &chan->flags)) {
1070 __unpack_extended_control(get_unaligned_le32(skb->data),
1071 &bt_cb(skb)->l2cap);
1072 skb_pull(skb, L2CAP_EXT_CTRL_SIZE);
1073 } else {
1074 __unpack_enhanced_control(get_unaligned_le16(skb->data),
1075 &bt_cb(skb)->l2cap);
1076 skb_pull(skb, L2CAP_ENH_CTRL_SIZE);
1077 }
1078}
1079
1080static u32 __pack_extended_control(struct l2cap_ctrl *control)
1081{
1082 u32 packed;
1083
1084 packed = control->reqseq << L2CAP_EXT_CTRL_REQSEQ_SHIFT;
1085 packed |= control->final << L2CAP_EXT_CTRL_FINAL_SHIFT;
1086
1087 if (control->sframe) {
1088 packed |= control->poll << L2CAP_EXT_CTRL_POLL_SHIFT;
1089 packed |= control->super << L2CAP_EXT_CTRL_SUPER_SHIFT;
1090 packed |= L2CAP_EXT_CTRL_FRAME_TYPE;
1091 } else {
1092 packed |= control->sar << L2CAP_EXT_CTRL_SAR_SHIFT;
1093 packed |= control->txseq << L2CAP_EXT_CTRL_TXSEQ_SHIFT;
1094 }
1095
1096 return packed;
1097}
1098
1099static u16 __pack_enhanced_control(struct l2cap_ctrl *control)
1100{
1101 u16 packed;
1102
1103 packed = control->reqseq << L2CAP_CTRL_REQSEQ_SHIFT;
1104 packed |= control->final << L2CAP_CTRL_FINAL_SHIFT;
1105
1106 if (control->sframe) {
1107 packed |= control->poll << L2CAP_CTRL_POLL_SHIFT;
1108 packed |= control->super << L2CAP_CTRL_SUPER_SHIFT;
1109 packed |= L2CAP_CTRL_FRAME_TYPE;
1110 } else {
1111 packed |= control->sar << L2CAP_CTRL_SAR_SHIFT;
1112 packed |= control->txseq << L2CAP_CTRL_TXSEQ_SHIFT;
1113 }
1114
1115 return packed;
1116}
1117
1118static inline void __pack_control(struct l2cap_chan *chan,
1119 struct l2cap_ctrl *control,
1120 struct sk_buff *skb)
1121{
1122 if (test_bit(FLAG_EXT_CTRL, &chan->flags)) {
1123 put_unaligned_le32(__pack_extended_control(control),
1124 skb->data + L2CAP_HDR_SIZE);
1125 } else {
1126 put_unaligned_le16(__pack_enhanced_control(control),
1127 skb->data + L2CAP_HDR_SIZE);
1128 }
1129}
1130
1131static inline unsigned int __ertm_hdr_size(struct l2cap_chan *chan)
1132{
1133 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
1134 return L2CAP_EXT_HDR_SIZE;
1135 else
1136 return L2CAP_ENH_HDR_SIZE;
1137}
1138
1139static struct sk_buff *l2cap_create_sframe_pdu(struct l2cap_chan *chan,
1140 u32 control)
1141{
1142 struct sk_buff *skb;
1143 struct l2cap_hdr *lh;
1144 int hlen = __ertm_hdr_size(chan);
1145
1146 if (chan->fcs == L2CAP_FCS_CRC16)
1147 hlen += L2CAP_FCS_SIZE;
1148
1149 skb = bt_skb_alloc(hlen, GFP_KERNEL);
1150
1151 if (!skb)
1152 return ERR_PTR(-ENOMEM);
1153
1154 lh = skb_put(skb, L2CAP_HDR_SIZE);
1155 lh->len = cpu_to_le16(hlen - L2CAP_HDR_SIZE);
1156 lh->cid = cpu_to_le16(chan->dcid);
1157
1158 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
1159 put_unaligned_le32(control, skb_put(skb, L2CAP_EXT_CTRL_SIZE));
1160 else
1161 put_unaligned_le16(control, skb_put(skb, L2CAP_ENH_CTRL_SIZE));
1162
1163 if (chan->fcs == L2CAP_FCS_CRC16) {
1164 u16 fcs = crc16(0, (u8 *)skb->data, skb->len);
1165 put_unaligned_le16(fcs, skb_put(skb, L2CAP_FCS_SIZE));
1166 }
1167
1168 skb->priority = HCI_PRIO_MAX;
1169 return skb;
1170}
1171
1172static void l2cap_send_sframe(struct l2cap_chan *chan,
1173 struct l2cap_ctrl *control)
1174{
1175 struct sk_buff *skb;
1176 u32 control_field;
1177
1178 BT_DBG("chan %p, control %p", chan, control);
1179
1180 if (!control->sframe)
1181 return;
1182
1183 if (__chan_is_moving(chan))
1184 return;
1185
1186 if (test_and_clear_bit(CONN_SEND_FBIT, &chan->conn_state) &&
1187 !control->poll)
1188 control->final = 1;
1189
1190 if (control->super == L2CAP_SUPER_RR)
1191 clear_bit(CONN_RNR_SENT, &chan->conn_state);
1192 else if (control->super == L2CAP_SUPER_RNR)
1193 set_bit(CONN_RNR_SENT, &chan->conn_state);
1194
1195 if (control->super != L2CAP_SUPER_SREJ) {
1196 chan->last_acked_seq = control->reqseq;
1197 __clear_ack_timer(chan);
1198 }
1199
1200 BT_DBG("reqseq %d, final %d, poll %d, super %d", control->reqseq,
1201 control->final, control->poll, control->super);
1202
1203 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
1204 control_field = __pack_extended_control(control);
1205 else
1206 control_field = __pack_enhanced_control(control);
1207
1208 skb = l2cap_create_sframe_pdu(chan, control_field);
1209 if (!IS_ERR(skb))
1210 l2cap_do_send(chan, skb);
1211}
1212
1213static void l2cap_send_rr_or_rnr(struct l2cap_chan *chan, bool poll)
1214{
1215 struct l2cap_ctrl control;
1216
1217 BT_DBG("chan %p, poll %d", chan, poll);
1218
1219 memset(&control, 0, sizeof(control));
1220 control.sframe = 1;
1221 control.poll = poll;
1222
1223 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state))
1224 control.super = L2CAP_SUPER_RNR;
1225 else
1226 control.super = L2CAP_SUPER_RR;
1227
1228 control.reqseq = chan->buffer_seq;
1229 l2cap_send_sframe(chan, &control);
1230}
1231
1232static inline int __l2cap_no_conn_pending(struct l2cap_chan *chan)
1233{
1234 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED)
1235 return true;
1236
1237 return !test_bit(CONF_CONNECT_PEND, &chan->conf_state);
1238}
1239
1240static bool __amp_capable(struct l2cap_chan *chan)
1241{
1242 struct l2cap_conn *conn = chan->conn;
1243 struct hci_dev *hdev;
1244 bool amp_available = false;
1245
1246 if (!(conn->local_fixed_chan & L2CAP_FC_A2MP))
1247 return false;
1248
1249 if (!(conn->remote_fixed_chan & L2CAP_FC_A2MP))
1250 return false;
1251
1252 read_lock(&hci_dev_list_lock);
1253 list_for_each_entry(hdev, &hci_dev_list, list) {
1254 if (hdev->amp_type != AMP_TYPE_BREDR &&
1255 test_bit(HCI_UP, &hdev->flags)) {
1256 amp_available = true;
1257 break;
1258 }
1259 }
1260 read_unlock(&hci_dev_list_lock);
1261
1262 if (chan->chan_policy == BT_CHANNEL_POLICY_AMP_PREFERRED)
1263 return amp_available;
1264
1265 return false;
1266}
1267
1268static bool l2cap_check_efs(struct l2cap_chan *chan)
1269{
1270 /* Check EFS parameters */
1271 return true;
1272}
1273
1274void l2cap_send_conn_req(struct l2cap_chan *chan)
1275{
1276 struct l2cap_conn *conn = chan->conn;
1277 struct l2cap_conn_req req;
1278
1279 req.scid = cpu_to_le16(chan->scid);
1280 req.psm = chan->psm;
1281
1282 chan->ident = l2cap_get_ident(conn);
1283
1284 set_bit(CONF_CONNECT_PEND, &chan->conf_state);
1285
1286 l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_REQ, sizeof(req), &req);
1287}
1288
1289static void l2cap_send_create_chan_req(struct l2cap_chan *chan, u8 amp_id)
1290{
1291 struct l2cap_create_chan_req req;
1292 req.scid = cpu_to_le16(chan->scid);
1293 req.psm = chan->psm;
1294 req.amp_id = amp_id;
1295
1296 chan->ident = l2cap_get_ident(chan->conn);
1297
1298 l2cap_send_cmd(chan->conn, chan->ident, L2CAP_CREATE_CHAN_REQ,
1299 sizeof(req), &req);
1300}
1301
1302static void l2cap_move_setup(struct l2cap_chan *chan)
1303{
1304 struct sk_buff *skb;
1305
1306 BT_DBG("chan %p", chan);
1307
1308 if (chan->mode != L2CAP_MODE_ERTM)
1309 return;
1310
1311 __clear_retrans_timer(chan);
1312 __clear_monitor_timer(chan);
1313 __clear_ack_timer(chan);
1314
1315 chan->retry_count = 0;
1316 skb_queue_walk(&chan->tx_q, skb) {
1317 if (bt_cb(skb)->l2cap.retries)
1318 bt_cb(skb)->l2cap.retries = 1;
1319 else
1320 break;
1321 }
1322
1323 chan->expected_tx_seq = chan->buffer_seq;
1324
1325 clear_bit(CONN_REJ_ACT, &chan->conn_state);
1326 clear_bit(CONN_SREJ_ACT, &chan->conn_state);
1327 l2cap_seq_list_clear(&chan->retrans_list);
1328 l2cap_seq_list_clear(&chan->srej_list);
1329 skb_queue_purge(&chan->srej_q);
1330
1331 chan->tx_state = L2CAP_TX_STATE_XMIT;
1332 chan->rx_state = L2CAP_RX_STATE_MOVE;
1333
1334 set_bit(CONN_REMOTE_BUSY, &chan->conn_state);
1335}
1336
1337static void l2cap_move_done(struct l2cap_chan *chan)
1338{
1339 u8 move_role = chan->move_role;
1340 BT_DBG("chan %p", chan);
1341
1342 chan->move_state = L2CAP_MOVE_STABLE;
1343 chan->move_role = L2CAP_MOVE_ROLE_NONE;
1344
1345 if (chan->mode != L2CAP_MODE_ERTM)
1346 return;
1347
1348 switch (move_role) {
1349 case L2CAP_MOVE_ROLE_INITIATOR:
1350 l2cap_tx(chan, NULL, NULL, L2CAP_EV_EXPLICIT_POLL);
1351 chan->rx_state = L2CAP_RX_STATE_WAIT_F;
1352 break;
1353 case L2CAP_MOVE_ROLE_RESPONDER:
1354 chan->rx_state = L2CAP_RX_STATE_WAIT_P;
1355 break;
1356 }
1357}
1358
1359static void l2cap_chan_ready(struct l2cap_chan *chan)
1360{
1361 /* The channel may have already been flagged as connected in
1362 * case of receiving data before the L2CAP info req/rsp
1363 * procedure is complete.
1364 */
1365 if (chan->state == BT_CONNECTED)
1366 return;
1367
1368 /* This clears all conf flags, including CONF_NOT_COMPLETE */
1369 chan->conf_state = 0;
1370 __clear_chan_timer(chan);
1371
1372 switch (chan->mode) {
1373 case L2CAP_MODE_LE_FLOWCTL:
1374 case L2CAP_MODE_EXT_FLOWCTL:
1375 if (!chan->tx_credits)
1376 chan->ops->suspend(chan);
1377 break;
1378 }
1379
1380 chan->state = BT_CONNECTED;
1381
1382 chan->ops->ready(chan);
1383}
1384
1385static void l2cap_le_connect(struct l2cap_chan *chan)
1386{
1387 struct l2cap_conn *conn = chan->conn;
1388 struct l2cap_le_conn_req req;
1389
1390 if (test_and_set_bit(FLAG_LE_CONN_REQ_SENT, &chan->flags))
1391 return;
1392
1393 if (!chan->imtu)
1394 chan->imtu = chan->conn->mtu;
1395
1396 l2cap_le_flowctl_init(chan, 0);
1397
1398 memset(&req, 0, sizeof(req));
1399 req.psm = chan->psm;
1400 req.scid = cpu_to_le16(chan->scid);
1401 req.mtu = cpu_to_le16(chan->imtu);
1402 req.mps = cpu_to_le16(chan->mps);
1403 req.credits = cpu_to_le16(chan->rx_credits);
1404
1405 chan->ident = l2cap_get_ident(conn);
1406
1407 l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CONN_REQ,
1408 sizeof(req), &req);
1409}
1410
1411struct l2cap_ecred_conn_data {
1412 struct {
1413 struct l2cap_ecred_conn_req req;
1414 __le16 scid[5];
1415 } __packed pdu;
1416 struct l2cap_chan *chan;
1417 struct pid *pid;
1418 int count;
1419};
1420
1421static void l2cap_ecred_defer_connect(struct l2cap_chan *chan, void *data)
1422{
1423 struct l2cap_ecred_conn_data *conn = data;
1424 struct pid *pid;
1425
1426 if (chan == conn->chan)
1427 return;
1428
1429 if (!test_and_clear_bit(FLAG_DEFER_SETUP, &chan->flags))
1430 return;
1431
1432 pid = chan->ops->get_peer_pid(chan);
1433
1434 /* Only add deferred channels with the same PID/PSM */
1435 if (conn->pid != pid || chan->psm != conn->chan->psm || chan->ident ||
1436 chan->mode != L2CAP_MODE_EXT_FLOWCTL || chan->state != BT_CONNECT)
1437 return;
1438
1439 if (test_and_set_bit(FLAG_ECRED_CONN_REQ_SENT, &chan->flags))
1440 return;
1441
1442 l2cap_ecred_init(chan, 0);
1443
1444 /* Set the same ident so we can match on the rsp */
1445 chan->ident = conn->chan->ident;
1446
1447 /* Include all channels deferred */
1448 conn->pdu.scid[conn->count] = cpu_to_le16(chan->scid);
1449
1450 conn->count++;
1451}
1452
1453static void l2cap_ecred_connect(struct l2cap_chan *chan)
1454{
1455 struct l2cap_conn *conn = chan->conn;
1456 struct l2cap_ecred_conn_data data;
1457
1458 if (test_bit(FLAG_DEFER_SETUP, &chan->flags))
1459 return;
1460
1461 if (test_and_set_bit(FLAG_ECRED_CONN_REQ_SENT, &chan->flags))
1462 return;
1463
1464 l2cap_ecred_init(chan, 0);
1465
1466 memset(&data, 0, sizeof(data));
1467 data.pdu.req.psm = chan->psm;
1468 data.pdu.req.mtu = cpu_to_le16(chan->imtu);
1469 data.pdu.req.mps = cpu_to_le16(chan->mps);
1470 data.pdu.req.credits = cpu_to_le16(chan->rx_credits);
1471 data.pdu.scid[0] = cpu_to_le16(chan->scid);
1472
1473 chan->ident = l2cap_get_ident(conn);
1474
1475 data.count = 1;
1476 data.chan = chan;
1477 data.pid = chan->ops->get_peer_pid(chan);
1478
1479 __l2cap_chan_list(conn, l2cap_ecred_defer_connect, &data);
1480
1481 l2cap_send_cmd(conn, chan->ident, L2CAP_ECRED_CONN_REQ,
1482 sizeof(data.pdu.req) + data.count * sizeof(__le16),
1483 &data.pdu);
1484}
1485
1486static void l2cap_le_start(struct l2cap_chan *chan)
1487{
1488 struct l2cap_conn *conn = chan->conn;
1489
1490 if (!smp_conn_security(conn->hcon, chan->sec_level))
1491 return;
1492
1493 if (!chan->psm) {
1494 l2cap_chan_ready(chan);
1495 return;
1496 }
1497
1498 if (chan->state == BT_CONNECT) {
1499 if (chan->mode == L2CAP_MODE_EXT_FLOWCTL)
1500 l2cap_ecred_connect(chan);
1501 else
1502 l2cap_le_connect(chan);
1503 }
1504}
1505
1506static void l2cap_start_connection(struct l2cap_chan *chan)
1507{
1508 if (__amp_capable(chan)) {
1509 BT_DBG("chan %p AMP capable: discover AMPs", chan);
1510 a2mp_discover_amp(chan);
1511 } else if (chan->conn->hcon->type == LE_LINK) {
1512 l2cap_le_start(chan);
1513 } else {
1514 l2cap_send_conn_req(chan);
1515 }
1516}
1517
1518static void l2cap_request_info(struct l2cap_conn *conn)
1519{
1520 struct l2cap_info_req req;
1521
1522 if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT)
1523 return;
1524
1525 req.type = cpu_to_le16(L2CAP_IT_FEAT_MASK);
1526
1527 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_SENT;
1528 conn->info_ident = l2cap_get_ident(conn);
1529
1530 schedule_delayed_work(&conn->info_timer, L2CAP_INFO_TIMEOUT);
1531
1532 l2cap_send_cmd(conn, conn->info_ident, L2CAP_INFO_REQ,
1533 sizeof(req), &req);
1534}
1535
1536static bool l2cap_check_enc_key_size(struct hci_conn *hcon)
1537{
1538 /* The minimum encryption key size needs to be enforced by the
1539 * host stack before establishing any L2CAP connections. The
1540 * specification in theory allows a minimum of 1, but to align
1541 * BR/EDR and LE transports, a minimum of 7 is chosen.
1542 *
1543 * This check might also be called for unencrypted connections
1544 * that have no key size requirements. Ensure that the link is
1545 * actually encrypted before enforcing a key size.
1546 */
1547 int min_key_size = hcon->hdev->min_enc_key_size;
1548
1549 /* On FIPS security level, key size must be 16 bytes */
1550 if (hcon->sec_level == BT_SECURITY_FIPS)
1551 min_key_size = 16;
1552
1553 return (!test_bit(HCI_CONN_ENCRYPT, &hcon->flags) ||
1554 hcon->enc_key_size >= min_key_size);
1555}
1556
1557static void l2cap_do_start(struct l2cap_chan *chan)
1558{
1559 struct l2cap_conn *conn = chan->conn;
1560
1561 if (conn->hcon->type == LE_LINK) {
1562 l2cap_le_start(chan);
1563 return;
1564 }
1565
1566 if (!(conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT)) {
1567 l2cap_request_info(conn);
1568 return;
1569 }
1570
1571 if (!(conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE))
1572 return;
1573
1574 if (!l2cap_chan_check_security(chan, true) ||
1575 !__l2cap_no_conn_pending(chan))
1576 return;
1577
1578 if (l2cap_check_enc_key_size(conn->hcon))
1579 l2cap_start_connection(chan);
1580 else
1581 __set_chan_timer(chan, L2CAP_DISC_TIMEOUT);
1582}
1583
1584static inline int l2cap_mode_supported(__u8 mode, __u32 feat_mask)
1585{
1586 u32 local_feat_mask = l2cap_feat_mask;
1587 if (!disable_ertm)
1588 local_feat_mask |= L2CAP_FEAT_ERTM | L2CAP_FEAT_STREAMING;
1589
1590 switch (mode) {
1591 case L2CAP_MODE_ERTM:
1592 return L2CAP_FEAT_ERTM & feat_mask & local_feat_mask;
1593 case L2CAP_MODE_STREAMING:
1594 return L2CAP_FEAT_STREAMING & feat_mask & local_feat_mask;
1595 default:
1596 return 0x00;
1597 }
1598}
1599
1600static void l2cap_send_disconn_req(struct l2cap_chan *chan, int err)
1601{
1602 struct l2cap_conn *conn = chan->conn;
1603 struct l2cap_disconn_req req;
1604
1605 if (!conn)
1606 return;
1607
1608 if (chan->mode == L2CAP_MODE_ERTM && chan->state == BT_CONNECTED) {
1609 __clear_retrans_timer(chan);
1610 __clear_monitor_timer(chan);
1611 __clear_ack_timer(chan);
1612 }
1613
1614 if (chan->scid == L2CAP_CID_A2MP) {
1615 l2cap_state_change(chan, BT_DISCONN);
1616 return;
1617 }
1618
1619 req.dcid = cpu_to_le16(chan->dcid);
1620 req.scid = cpu_to_le16(chan->scid);
1621 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_DISCONN_REQ,
1622 sizeof(req), &req);
1623
1624 l2cap_state_change_and_error(chan, BT_DISCONN, err);
1625}
1626
1627/* ---- L2CAP connections ---- */
1628static void l2cap_conn_start(struct l2cap_conn *conn)
1629{
1630 struct l2cap_chan *chan, *tmp;
1631
1632 BT_DBG("conn %p", conn);
1633
1634 mutex_lock(&conn->chan_lock);
1635
1636 list_for_each_entry_safe(chan, tmp, &conn->chan_l, list) {
1637 l2cap_chan_lock(chan);
1638
1639 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) {
1640 l2cap_chan_ready(chan);
1641 l2cap_chan_unlock(chan);
1642 continue;
1643 }
1644
1645 if (chan->state == BT_CONNECT) {
1646 if (!l2cap_chan_check_security(chan, true) ||
1647 !__l2cap_no_conn_pending(chan)) {
1648 l2cap_chan_unlock(chan);
1649 continue;
1650 }
1651
1652 if (!l2cap_mode_supported(chan->mode, conn->feat_mask)
1653 && test_bit(CONF_STATE2_DEVICE,
1654 &chan->conf_state)) {
1655 l2cap_chan_close(chan, ECONNRESET);
1656 l2cap_chan_unlock(chan);
1657 continue;
1658 }
1659
1660 if (l2cap_check_enc_key_size(conn->hcon))
1661 l2cap_start_connection(chan);
1662 else
1663 l2cap_chan_close(chan, ECONNREFUSED);
1664
1665 } else if (chan->state == BT_CONNECT2) {
1666 struct l2cap_conn_rsp rsp;
1667 char buf[128];
1668 rsp.scid = cpu_to_le16(chan->dcid);
1669 rsp.dcid = cpu_to_le16(chan->scid);
1670
1671 if (l2cap_chan_check_security(chan, false)) {
1672 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) {
1673 rsp.result = cpu_to_le16(L2CAP_CR_PEND);
1674 rsp.status = cpu_to_le16(L2CAP_CS_AUTHOR_PEND);
1675 chan->ops->defer(chan);
1676
1677 } else {
1678 l2cap_state_change(chan, BT_CONFIG);
1679 rsp.result = cpu_to_le16(L2CAP_CR_SUCCESS);
1680 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
1681 }
1682 } else {
1683 rsp.result = cpu_to_le16(L2CAP_CR_PEND);
1684 rsp.status = cpu_to_le16(L2CAP_CS_AUTHEN_PEND);
1685 }
1686
1687 l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_RSP,
1688 sizeof(rsp), &rsp);
1689
1690 if (test_bit(CONF_REQ_SENT, &chan->conf_state) ||
1691 rsp.result != L2CAP_CR_SUCCESS) {
1692 l2cap_chan_unlock(chan);
1693 continue;
1694 }
1695
1696 set_bit(CONF_REQ_SENT, &chan->conf_state);
1697 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
1698 l2cap_build_conf_req(chan, buf, sizeof(buf)), buf);
1699 chan->num_conf_req++;
1700 }
1701
1702 l2cap_chan_unlock(chan);
1703 }
1704
1705 mutex_unlock(&conn->chan_lock);
1706}
1707
1708static void l2cap_le_conn_ready(struct l2cap_conn *conn)
1709{
1710 struct hci_conn *hcon = conn->hcon;
1711 struct hci_dev *hdev = hcon->hdev;
1712
1713 BT_DBG("%s conn %p", hdev->name, conn);
1714
1715 /* For outgoing pairing which doesn't necessarily have an
1716 * associated socket (e.g. mgmt_pair_device).
1717 */
1718 if (hcon->out)
1719 smp_conn_security(hcon, hcon->pending_sec_level);
1720
1721 /* For LE peripheral connections, make sure the connection interval
1722 * is in the range of the minimum and maximum interval that has
1723 * been configured for this connection. If not, then trigger
1724 * the connection update procedure.
1725 */
1726 if (hcon->role == HCI_ROLE_SLAVE &&
1727 (hcon->le_conn_interval < hcon->le_conn_min_interval ||
1728 hcon->le_conn_interval > hcon->le_conn_max_interval)) {
1729 struct l2cap_conn_param_update_req req;
1730
1731 req.min = cpu_to_le16(hcon->le_conn_min_interval);
1732 req.max = cpu_to_le16(hcon->le_conn_max_interval);
1733 req.latency = cpu_to_le16(hcon->le_conn_latency);
1734 req.to_multiplier = cpu_to_le16(hcon->le_supv_timeout);
1735
1736 l2cap_send_cmd(conn, l2cap_get_ident(conn),
1737 L2CAP_CONN_PARAM_UPDATE_REQ, sizeof(req), &req);
1738 }
1739}
1740
1741static void l2cap_conn_ready(struct l2cap_conn *conn)
1742{
1743 struct l2cap_chan *chan;
1744 struct hci_conn *hcon = conn->hcon;
1745
1746 BT_DBG("conn %p", conn);
1747
1748 if (hcon->type == ACL_LINK)
1749 l2cap_request_info(conn);
1750
1751 mutex_lock(&conn->chan_lock);
1752
1753 list_for_each_entry(chan, &conn->chan_l, list) {
1754
1755 l2cap_chan_lock(chan);
1756
1757 if (chan->scid == L2CAP_CID_A2MP) {
1758 l2cap_chan_unlock(chan);
1759 continue;
1760 }
1761
1762 if (hcon->type == LE_LINK) {
1763 l2cap_le_start(chan);
1764 } else if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) {
1765 if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE)
1766 l2cap_chan_ready(chan);
1767 } else if (chan->state == BT_CONNECT) {
1768 l2cap_do_start(chan);
1769 }
1770
1771 l2cap_chan_unlock(chan);
1772 }
1773
1774 mutex_unlock(&conn->chan_lock);
1775
1776 if (hcon->type == LE_LINK)
1777 l2cap_le_conn_ready(conn);
1778
1779 queue_work(hcon->hdev->workqueue, &conn->pending_rx_work);
1780}
1781
1782/* Notify sockets that we cannot guaranty reliability anymore */
1783static void l2cap_conn_unreliable(struct l2cap_conn *conn, int err)
1784{
1785 struct l2cap_chan *chan;
1786
1787 BT_DBG("conn %p", conn);
1788
1789 mutex_lock(&conn->chan_lock);
1790
1791 list_for_each_entry(chan, &conn->chan_l, list) {
1792 if (test_bit(FLAG_FORCE_RELIABLE, &chan->flags))
1793 l2cap_chan_set_err(chan, err);
1794 }
1795
1796 mutex_unlock(&conn->chan_lock);
1797}
1798
1799static void l2cap_info_timeout(struct work_struct *work)
1800{
1801 struct l2cap_conn *conn = container_of(work, struct l2cap_conn,
1802 info_timer.work);
1803
1804 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
1805 conn->info_ident = 0;
1806
1807 l2cap_conn_start(conn);
1808}
1809
1810/*
1811 * l2cap_user
1812 * External modules can register l2cap_user objects on l2cap_conn. The ->probe
1813 * callback is called during registration. The ->remove callback is called
1814 * during unregistration.
1815 * An l2cap_user object can either be explicitly unregistered or when the
1816 * underlying l2cap_conn object is deleted. This guarantees that l2cap->hcon,
1817 * l2cap->hchan, .. are valid as long as the remove callback hasn't been called.
1818 * External modules must own a reference to the l2cap_conn object if they intend
1819 * to call l2cap_unregister_user(). The l2cap_conn object might get destroyed at
1820 * any time if they don't.
1821 */
1822
1823int l2cap_register_user(struct l2cap_conn *conn, struct l2cap_user *user)
1824{
1825 struct hci_dev *hdev = conn->hcon->hdev;
1826 int ret;
1827
1828 /* We need to check whether l2cap_conn is registered. If it is not, we
1829 * must not register the l2cap_user. l2cap_conn_del() is unregisters
1830 * l2cap_conn objects, but doesn't provide its own locking. Instead, it
1831 * relies on the parent hci_conn object to be locked. This itself relies
1832 * on the hci_dev object to be locked. So we must lock the hci device
1833 * here, too. */
1834
1835 hci_dev_lock(hdev);
1836
1837 if (!list_empty(&user->list)) {
1838 ret = -EINVAL;
1839 goto out_unlock;
1840 }
1841
1842 /* conn->hchan is NULL after l2cap_conn_del() was called */
1843 if (!conn->hchan) {
1844 ret = -ENODEV;
1845 goto out_unlock;
1846 }
1847
1848 ret = user->probe(conn, user);
1849 if (ret)
1850 goto out_unlock;
1851
1852 list_add(&user->list, &conn->users);
1853 ret = 0;
1854
1855out_unlock:
1856 hci_dev_unlock(hdev);
1857 return ret;
1858}
1859EXPORT_SYMBOL(l2cap_register_user);
1860
1861void l2cap_unregister_user(struct l2cap_conn *conn, struct l2cap_user *user)
1862{
1863 struct hci_dev *hdev = conn->hcon->hdev;
1864
1865 hci_dev_lock(hdev);
1866
1867 if (list_empty(&user->list))
1868 goto out_unlock;
1869
1870 list_del_init(&user->list);
1871 user->remove(conn, user);
1872
1873out_unlock:
1874 hci_dev_unlock(hdev);
1875}
1876EXPORT_SYMBOL(l2cap_unregister_user);
1877
1878static void l2cap_unregister_all_users(struct l2cap_conn *conn)
1879{
1880 struct l2cap_user *user;
1881
1882 while (!list_empty(&conn->users)) {
1883 user = list_first_entry(&conn->users, struct l2cap_user, list);
1884 list_del_init(&user->list);
1885 user->remove(conn, user);
1886 }
1887}
1888
1889static void l2cap_conn_del(struct hci_conn *hcon, int err)
1890{
1891 struct l2cap_conn *conn = hcon->l2cap_data;
1892 struct l2cap_chan *chan, *l;
1893
1894 if (!conn)
1895 return;
1896
1897 BT_DBG("hcon %p conn %p, err %d", hcon, conn, err);
1898
1899 kfree_skb(conn->rx_skb);
1900
1901 skb_queue_purge(&conn->pending_rx);
1902
1903 /* We can not call flush_work(&conn->pending_rx_work) here since we
1904 * might block if we are running on a worker from the same workqueue
1905 * pending_rx_work is waiting on.
1906 */
1907 if (work_pending(&conn->pending_rx_work))
1908 cancel_work_sync(&conn->pending_rx_work);
1909
1910 cancel_delayed_work_sync(&conn->id_addr_timer);
1911
1912 l2cap_unregister_all_users(conn);
1913
1914 /* Force the connection to be immediately dropped */
1915 hcon->disc_timeout = 0;
1916
1917 mutex_lock(&conn->chan_lock);
1918
1919 /* Kill channels */
1920 list_for_each_entry_safe(chan, l, &conn->chan_l, list) {
1921 l2cap_chan_hold(chan);
1922 l2cap_chan_lock(chan);
1923
1924 l2cap_chan_del(chan, err);
1925
1926 chan->ops->close(chan);
1927
1928 l2cap_chan_unlock(chan);
1929 l2cap_chan_put(chan);
1930 }
1931
1932 mutex_unlock(&conn->chan_lock);
1933
1934 hci_chan_del(conn->hchan);
1935
1936 if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT)
1937 cancel_delayed_work_sync(&conn->info_timer);
1938
1939 hcon->l2cap_data = NULL;
1940 conn->hchan = NULL;
1941 l2cap_conn_put(conn);
1942}
1943
1944static void l2cap_conn_free(struct kref *ref)
1945{
1946 struct l2cap_conn *conn = container_of(ref, struct l2cap_conn, ref);
1947
1948 hci_conn_put(conn->hcon);
1949 kfree(conn);
1950}
1951
1952struct l2cap_conn *l2cap_conn_get(struct l2cap_conn *conn)
1953{
1954 kref_get(&conn->ref);
1955 return conn;
1956}
1957EXPORT_SYMBOL(l2cap_conn_get);
1958
1959void l2cap_conn_put(struct l2cap_conn *conn)
1960{
1961 kref_put(&conn->ref, l2cap_conn_free);
1962}
1963EXPORT_SYMBOL(l2cap_conn_put);
1964
1965/* ---- Socket interface ---- */
1966
1967/* Find socket with psm and source / destination bdaddr.
1968 * Returns closest match.
1969 */
1970static struct l2cap_chan *l2cap_global_chan_by_psm(int state, __le16 psm,
1971 bdaddr_t *src,
1972 bdaddr_t *dst,
1973 u8 link_type)
1974{
1975 struct l2cap_chan *c, *tmp, *c1 = NULL;
1976
1977 read_lock(&chan_list_lock);
1978
1979 list_for_each_entry_safe(c, tmp, &chan_list, global_l) {
1980 if (state && c->state != state)
1981 continue;
1982
1983 if (link_type == ACL_LINK && c->src_type != BDADDR_BREDR)
1984 continue;
1985
1986 if (link_type == LE_LINK && c->src_type == BDADDR_BREDR)
1987 continue;
1988
1989 if (c->chan_type != L2CAP_CHAN_FIXED && c->psm == psm) {
1990 int src_match, dst_match;
1991 int src_any, dst_any;
1992
1993 /* Exact match. */
1994 src_match = !bacmp(&c->src, src);
1995 dst_match = !bacmp(&c->dst, dst);
1996 if (src_match && dst_match) {
1997 if (!l2cap_chan_hold_unless_zero(c))
1998 continue;
1999
2000 read_unlock(&chan_list_lock);
2001 return c;
2002 }
2003
2004 /* Closest match */
2005 src_any = !bacmp(&c->src, BDADDR_ANY);
2006 dst_any = !bacmp(&c->dst, BDADDR_ANY);
2007 if ((src_match && dst_any) || (src_any && dst_match) ||
2008 (src_any && dst_any))
2009 c1 = c;
2010 }
2011 }
2012
2013 if (c1)
2014 c1 = l2cap_chan_hold_unless_zero(c1);
2015
2016 read_unlock(&chan_list_lock);
2017
2018 return c1;
2019}
2020
2021static void l2cap_monitor_timeout(struct work_struct *work)
2022{
2023 struct l2cap_chan *chan = container_of(work, struct l2cap_chan,
2024 monitor_timer.work);
2025
2026 BT_DBG("chan %p", chan);
2027
2028 l2cap_chan_lock(chan);
2029
2030 if (!chan->conn) {
2031 l2cap_chan_unlock(chan);
2032 l2cap_chan_put(chan);
2033 return;
2034 }
2035
2036 l2cap_tx(chan, NULL, NULL, L2CAP_EV_MONITOR_TO);
2037
2038 l2cap_chan_unlock(chan);
2039 l2cap_chan_put(chan);
2040}
2041
2042static void l2cap_retrans_timeout(struct work_struct *work)
2043{
2044 struct l2cap_chan *chan = container_of(work, struct l2cap_chan,
2045 retrans_timer.work);
2046
2047 BT_DBG("chan %p", chan);
2048
2049 l2cap_chan_lock(chan);
2050
2051 if (!chan->conn) {
2052 l2cap_chan_unlock(chan);
2053 l2cap_chan_put(chan);
2054 return;
2055 }
2056
2057 l2cap_tx(chan, NULL, NULL, L2CAP_EV_RETRANS_TO);
2058 l2cap_chan_unlock(chan);
2059 l2cap_chan_put(chan);
2060}
2061
2062static void l2cap_streaming_send(struct l2cap_chan *chan,
2063 struct sk_buff_head *skbs)
2064{
2065 struct sk_buff *skb;
2066 struct l2cap_ctrl *control;
2067
2068 BT_DBG("chan %p, skbs %p", chan, skbs);
2069
2070 if (__chan_is_moving(chan))
2071 return;
2072
2073 skb_queue_splice_tail_init(skbs, &chan->tx_q);
2074
2075 while (!skb_queue_empty(&chan->tx_q)) {
2076
2077 skb = skb_dequeue(&chan->tx_q);
2078
2079 bt_cb(skb)->l2cap.retries = 1;
2080 control = &bt_cb(skb)->l2cap;
2081
2082 control->reqseq = 0;
2083 control->txseq = chan->next_tx_seq;
2084
2085 __pack_control(chan, control, skb);
2086
2087 if (chan->fcs == L2CAP_FCS_CRC16) {
2088 u16 fcs = crc16(0, (u8 *) skb->data, skb->len);
2089 put_unaligned_le16(fcs, skb_put(skb, L2CAP_FCS_SIZE));
2090 }
2091
2092 l2cap_do_send(chan, skb);
2093
2094 BT_DBG("Sent txseq %u", control->txseq);
2095
2096 chan->next_tx_seq = __next_seq(chan, chan->next_tx_seq);
2097 chan->frames_sent++;
2098 }
2099}
2100
2101static int l2cap_ertm_send(struct l2cap_chan *chan)
2102{
2103 struct sk_buff *skb, *tx_skb;
2104 struct l2cap_ctrl *control;
2105 int sent = 0;
2106
2107 BT_DBG("chan %p", chan);
2108
2109 if (chan->state != BT_CONNECTED)
2110 return -ENOTCONN;
2111
2112 if (test_bit(CONN_REMOTE_BUSY, &chan->conn_state))
2113 return 0;
2114
2115 if (__chan_is_moving(chan))
2116 return 0;
2117
2118 while (chan->tx_send_head &&
2119 chan->unacked_frames < chan->remote_tx_win &&
2120 chan->tx_state == L2CAP_TX_STATE_XMIT) {
2121
2122 skb = chan->tx_send_head;
2123
2124 bt_cb(skb)->l2cap.retries = 1;
2125 control = &bt_cb(skb)->l2cap;
2126
2127 if (test_and_clear_bit(CONN_SEND_FBIT, &chan->conn_state))
2128 control->final = 1;
2129
2130 control->reqseq = chan->buffer_seq;
2131 chan->last_acked_seq = chan->buffer_seq;
2132 control->txseq = chan->next_tx_seq;
2133
2134 __pack_control(chan, control, skb);
2135
2136 if (chan->fcs == L2CAP_FCS_CRC16) {
2137 u16 fcs = crc16(0, (u8 *) skb->data, skb->len);
2138 put_unaligned_le16(fcs, skb_put(skb, L2CAP_FCS_SIZE));
2139 }
2140
2141 /* Clone after data has been modified. Data is assumed to be
2142 read-only (for locking purposes) on cloned sk_buffs.
2143 */
2144 tx_skb = skb_clone(skb, GFP_KERNEL);
2145
2146 if (!tx_skb)
2147 break;
2148
2149 __set_retrans_timer(chan);
2150
2151 chan->next_tx_seq = __next_seq(chan, chan->next_tx_seq);
2152 chan->unacked_frames++;
2153 chan->frames_sent++;
2154 sent++;
2155
2156 if (skb_queue_is_last(&chan->tx_q, skb))
2157 chan->tx_send_head = NULL;
2158 else
2159 chan->tx_send_head = skb_queue_next(&chan->tx_q, skb);
2160
2161 l2cap_do_send(chan, tx_skb);
2162 BT_DBG("Sent txseq %u", control->txseq);
2163 }
2164
2165 BT_DBG("Sent %d, %u unacked, %u in ERTM queue", sent,
2166 chan->unacked_frames, skb_queue_len(&chan->tx_q));
2167
2168 return sent;
2169}
2170
2171static void l2cap_ertm_resend(struct l2cap_chan *chan)
2172{
2173 struct l2cap_ctrl control;
2174 struct sk_buff *skb;
2175 struct sk_buff *tx_skb;
2176 u16 seq;
2177
2178 BT_DBG("chan %p", chan);
2179
2180 if (test_bit(CONN_REMOTE_BUSY, &chan->conn_state))
2181 return;
2182
2183 if (__chan_is_moving(chan))
2184 return;
2185
2186 while (chan->retrans_list.head != L2CAP_SEQ_LIST_CLEAR) {
2187 seq = l2cap_seq_list_pop(&chan->retrans_list);
2188
2189 skb = l2cap_ertm_seq_in_queue(&chan->tx_q, seq);
2190 if (!skb) {
2191 BT_DBG("Error: Can't retransmit seq %d, frame missing",
2192 seq);
2193 continue;
2194 }
2195
2196 bt_cb(skb)->l2cap.retries++;
2197 control = bt_cb(skb)->l2cap;
2198
2199 if (chan->max_tx != 0 &&
2200 bt_cb(skb)->l2cap.retries > chan->max_tx) {
2201 BT_DBG("Retry limit exceeded (%d)", chan->max_tx);
2202 l2cap_send_disconn_req(chan, ECONNRESET);
2203 l2cap_seq_list_clear(&chan->retrans_list);
2204 break;
2205 }
2206
2207 control.reqseq = chan->buffer_seq;
2208 if (test_and_clear_bit(CONN_SEND_FBIT, &chan->conn_state))
2209 control.final = 1;
2210 else
2211 control.final = 0;
2212
2213 if (skb_cloned(skb)) {
2214 /* Cloned sk_buffs are read-only, so we need a
2215 * writeable copy
2216 */
2217 tx_skb = skb_copy(skb, GFP_KERNEL);
2218 } else {
2219 tx_skb = skb_clone(skb, GFP_KERNEL);
2220 }
2221
2222 if (!tx_skb) {
2223 l2cap_seq_list_clear(&chan->retrans_list);
2224 break;
2225 }
2226
2227 /* Update skb contents */
2228 if (test_bit(FLAG_EXT_CTRL, &chan->flags)) {
2229 put_unaligned_le32(__pack_extended_control(&control),
2230 tx_skb->data + L2CAP_HDR_SIZE);
2231 } else {
2232 put_unaligned_le16(__pack_enhanced_control(&control),
2233 tx_skb->data + L2CAP_HDR_SIZE);
2234 }
2235
2236 /* Update FCS */
2237 if (chan->fcs == L2CAP_FCS_CRC16) {
2238 u16 fcs = crc16(0, (u8 *) tx_skb->data,
2239 tx_skb->len - L2CAP_FCS_SIZE);
2240 put_unaligned_le16(fcs, skb_tail_pointer(tx_skb) -
2241 L2CAP_FCS_SIZE);
2242 }
2243
2244 l2cap_do_send(chan, tx_skb);
2245
2246 BT_DBG("Resent txseq %d", control.txseq);
2247
2248 chan->last_acked_seq = chan->buffer_seq;
2249 }
2250}
2251
2252static void l2cap_retransmit(struct l2cap_chan *chan,
2253 struct l2cap_ctrl *control)
2254{
2255 BT_DBG("chan %p, control %p", chan, control);
2256
2257 l2cap_seq_list_append(&chan->retrans_list, control->reqseq);
2258 l2cap_ertm_resend(chan);
2259}
2260
2261static void l2cap_retransmit_all(struct l2cap_chan *chan,
2262 struct l2cap_ctrl *control)
2263{
2264 struct sk_buff *skb;
2265
2266 BT_DBG("chan %p, control %p", chan, control);
2267
2268 if (control->poll)
2269 set_bit(CONN_SEND_FBIT, &chan->conn_state);
2270
2271 l2cap_seq_list_clear(&chan->retrans_list);
2272
2273 if (test_bit(CONN_REMOTE_BUSY, &chan->conn_state))
2274 return;
2275
2276 if (chan->unacked_frames) {
2277 skb_queue_walk(&chan->tx_q, skb) {
2278 if (bt_cb(skb)->l2cap.txseq == control->reqseq ||
2279 skb == chan->tx_send_head)
2280 break;
2281 }
2282
2283 skb_queue_walk_from(&chan->tx_q, skb) {
2284 if (skb == chan->tx_send_head)
2285 break;
2286
2287 l2cap_seq_list_append(&chan->retrans_list,
2288 bt_cb(skb)->l2cap.txseq);
2289 }
2290
2291 l2cap_ertm_resend(chan);
2292 }
2293}
2294
2295static void l2cap_send_ack(struct l2cap_chan *chan)
2296{
2297 struct l2cap_ctrl control;
2298 u16 frames_to_ack = __seq_offset(chan, chan->buffer_seq,
2299 chan->last_acked_seq);
2300 int threshold;
2301
2302 BT_DBG("chan %p last_acked_seq %d buffer_seq %d",
2303 chan, chan->last_acked_seq, chan->buffer_seq);
2304
2305 memset(&control, 0, sizeof(control));
2306 control.sframe = 1;
2307
2308 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state) &&
2309 chan->rx_state == L2CAP_RX_STATE_RECV) {
2310 __clear_ack_timer(chan);
2311 control.super = L2CAP_SUPER_RNR;
2312 control.reqseq = chan->buffer_seq;
2313 l2cap_send_sframe(chan, &control);
2314 } else {
2315 if (!test_bit(CONN_REMOTE_BUSY, &chan->conn_state)) {
2316 l2cap_ertm_send(chan);
2317 /* If any i-frames were sent, they included an ack */
2318 if (chan->buffer_seq == chan->last_acked_seq)
2319 frames_to_ack = 0;
2320 }
2321
2322 /* Ack now if the window is 3/4ths full.
2323 * Calculate without mul or div
2324 */
2325 threshold = chan->ack_win;
2326 threshold += threshold << 1;
2327 threshold >>= 2;
2328
2329 BT_DBG("frames_to_ack %u, threshold %d", frames_to_ack,
2330 threshold);
2331
2332 if (frames_to_ack >= threshold) {
2333 __clear_ack_timer(chan);
2334 control.super = L2CAP_SUPER_RR;
2335 control.reqseq = chan->buffer_seq;
2336 l2cap_send_sframe(chan, &control);
2337 frames_to_ack = 0;
2338 }
2339
2340 if (frames_to_ack)
2341 __set_ack_timer(chan);
2342 }
2343}
2344
2345static inline int l2cap_skbuff_fromiovec(struct l2cap_chan *chan,
2346 struct msghdr *msg, int len,
2347 int count, struct sk_buff *skb)
2348{
2349 struct l2cap_conn *conn = chan->conn;
2350 struct sk_buff **frag;
2351 int sent = 0;
2352
2353 if (!copy_from_iter_full(skb_put(skb, count), count, &msg->msg_iter))
2354 return -EFAULT;
2355
2356 sent += count;
2357 len -= count;
2358
2359 /* Continuation fragments (no L2CAP header) */
2360 frag = &skb_shinfo(skb)->frag_list;
2361 while (len) {
2362 struct sk_buff *tmp;
2363
2364 count = min_t(unsigned int, conn->mtu, len);
2365
2366 tmp = chan->ops->alloc_skb(chan, 0, count,
2367 msg->msg_flags & MSG_DONTWAIT);
2368 if (IS_ERR(tmp))
2369 return PTR_ERR(tmp);
2370
2371 *frag = tmp;
2372
2373 if (!copy_from_iter_full(skb_put(*frag, count), count,
2374 &msg->msg_iter))
2375 return -EFAULT;
2376
2377 sent += count;
2378 len -= count;
2379
2380 skb->len += (*frag)->len;
2381 skb->data_len += (*frag)->len;
2382
2383 frag = &(*frag)->next;
2384 }
2385
2386 return sent;
2387}
2388
2389static struct sk_buff *l2cap_create_connless_pdu(struct l2cap_chan *chan,
2390 struct msghdr *msg, size_t len)
2391{
2392 struct l2cap_conn *conn = chan->conn;
2393 struct sk_buff *skb;
2394 int err, count, hlen = L2CAP_HDR_SIZE + L2CAP_PSMLEN_SIZE;
2395 struct l2cap_hdr *lh;
2396
2397 BT_DBG("chan %p psm 0x%2.2x len %zu", chan,
2398 __le16_to_cpu(chan->psm), len);
2399
2400 count = min_t(unsigned int, (conn->mtu - hlen), len);
2401
2402 skb = chan->ops->alloc_skb(chan, hlen, count,
2403 msg->msg_flags & MSG_DONTWAIT);
2404 if (IS_ERR(skb))
2405 return skb;
2406
2407 /* Create L2CAP header */
2408 lh = skb_put(skb, L2CAP_HDR_SIZE);
2409 lh->cid = cpu_to_le16(chan->dcid);
2410 lh->len = cpu_to_le16(len + L2CAP_PSMLEN_SIZE);
2411 put_unaligned(chan->psm, (__le16 *) skb_put(skb, L2CAP_PSMLEN_SIZE));
2412
2413 err = l2cap_skbuff_fromiovec(chan, msg, len, count, skb);
2414 if (unlikely(err < 0)) {
2415 kfree_skb(skb);
2416 return ERR_PTR(err);
2417 }
2418 return skb;
2419}
2420
2421static struct sk_buff *l2cap_create_basic_pdu(struct l2cap_chan *chan,
2422 struct msghdr *msg, size_t len)
2423{
2424 struct l2cap_conn *conn = chan->conn;
2425 struct sk_buff *skb;
2426 int err, count;
2427 struct l2cap_hdr *lh;
2428
2429 BT_DBG("chan %p len %zu", chan, len);
2430
2431 count = min_t(unsigned int, (conn->mtu - L2CAP_HDR_SIZE), len);
2432
2433 skb = chan->ops->alloc_skb(chan, L2CAP_HDR_SIZE, count,
2434 msg->msg_flags & MSG_DONTWAIT);
2435 if (IS_ERR(skb))
2436 return skb;
2437
2438 /* Create L2CAP header */
2439 lh = skb_put(skb, L2CAP_HDR_SIZE);
2440 lh->cid = cpu_to_le16(chan->dcid);
2441 lh->len = cpu_to_le16(len);
2442
2443 err = l2cap_skbuff_fromiovec(chan, msg, len, count, skb);
2444 if (unlikely(err < 0)) {
2445 kfree_skb(skb);
2446 return ERR_PTR(err);
2447 }
2448 return skb;
2449}
2450
2451static struct sk_buff *l2cap_create_iframe_pdu(struct l2cap_chan *chan,
2452 struct msghdr *msg, size_t len,
2453 u16 sdulen)
2454{
2455 struct l2cap_conn *conn = chan->conn;
2456 struct sk_buff *skb;
2457 int err, count, hlen;
2458 struct l2cap_hdr *lh;
2459
2460 BT_DBG("chan %p len %zu", chan, len);
2461
2462 if (!conn)
2463 return ERR_PTR(-ENOTCONN);
2464
2465 hlen = __ertm_hdr_size(chan);
2466
2467 if (sdulen)
2468 hlen += L2CAP_SDULEN_SIZE;
2469
2470 if (chan->fcs == L2CAP_FCS_CRC16)
2471 hlen += L2CAP_FCS_SIZE;
2472
2473 count = min_t(unsigned int, (conn->mtu - hlen), len);
2474
2475 skb = chan->ops->alloc_skb(chan, hlen, count,
2476 msg->msg_flags & MSG_DONTWAIT);
2477 if (IS_ERR(skb))
2478 return skb;
2479
2480 /* Create L2CAP header */
2481 lh = skb_put(skb, L2CAP_HDR_SIZE);
2482 lh->cid = cpu_to_le16(chan->dcid);
2483 lh->len = cpu_to_le16(len + (hlen - L2CAP_HDR_SIZE));
2484
2485 /* Control header is populated later */
2486 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
2487 put_unaligned_le32(0, skb_put(skb, L2CAP_EXT_CTRL_SIZE));
2488 else
2489 put_unaligned_le16(0, skb_put(skb, L2CAP_ENH_CTRL_SIZE));
2490
2491 if (sdulen)
2492 put_unaligned_le16(sdulen, skb_put(skb, L2CAP_SDULEN_SIZE));
2493
2494 err = l2cap_skbuff_fromiovec(chan, msg, len, count, skb);
2495 if (unlikely(err < 0)) {
2496 kfree_skb(skb);
2497 return ERR_PTR(err);
2498 }
2499
2500 bt_cb(skb)->l2cap.fcs = chan->fcs;
2501 bt_cb(skb)->l2cap.retries = 0;
2502 return skb;
2503}
2504
2505static int l2cap_segment_sdu(struct l2cap_chan *chan,
2506 struct sk_buff_head *seg_queue,
2507 struct msghdr *msg, size_t len)
2508{
2509 struct sk_buff *skb;
2510 u16 sdu_len;
2511 size_t pdu_len;
2512 u8 sar;
2513
2514 BT_DBG("chan %p, msg %p, len %zu", chan, msg, len);
2515
2516 /* It is critical that ERTM PDUs fit in a single HCI fragment,
2517 * so fragmented skbs are not used. The HCI layer's handling
2518 * of fragmented skbs is not compatible with ERTM's queueing.
2519 */
2520
2521 /* PDU size is derived from the HCI MTU */
2522 pdu_len = chan->conn->mtu;
2523
2524 /* Constrain PDU size for BR/EDR connections */
2525 if (!chan->hs_hcon)
2526 pdu_len = min_t(size_t, pdu_len, L2CAP_BREDR_MAX_PAYLOAD);
2527
2528 /* Adjust for largest possible L2CAP overhead. */
2529 if (chan->fcs)
2530 pdu_len -= L2CAP_FCS_SIZE;
2531
2532 pdu_len -= __ertm_hdr_size(chan);
2533
2534 /* Remote device may have requested smaller PDUs */
2535 pdu_len = min_t(size_t, pdu_len, chan->remote_mps);
2536
2537 if (len <= pdu_len) {
2538 sar = L2CAP_SAR_UNSEGMENTED;
2539 sdu_len = 0;
2540 pdu_len = len;
2541 } else {
2542 sar = L2CAP_SAR_START;
2543 sdu_len = len;
2544 }
2545
2546 while (len > 0) {
2547 skb = l2cap_create_iframe_pdu(chan, msg, pdu_len, sdu_len);
2548
2549 if (IS_ERR(skb)) {
2550 __skb_queue_purge(seg_queue);
2551 return PTR_ERR(skb);
2552 }
2553
2554 bt_cb(skb)->l2cap.sar = sar;
2555 __skb_queue_tail(seg_queue, skb);
2556
2557 len -= pdu_len;
2558 if (sdu_len)
2559 sdu_len = 0;
2560
2561 if (len <= pdu_len) {
2562 sar = L2CAP_SAR_END;
2563 pdu_len = len;
2564 } else {
2565 sar = L2CAP_SAR_CONTINUE;
2566 }
2567 }
2568
2569 return 0;
2570}
2571
2572static struct sk_buff *l2cap_create_le_flowctl_pdu(struct l2cap_chan *chan,
2573 struct msghdr *msg,
2574 size_t len, u16 sdulen)
2575{
2576 struct l2cap_conn *conn = chan->conn;
2577 struct sk_buff *skb;
2578 int err, count, hlen;
2579 struct l2cap_hdr *lh;
2580
2581 BT_DBG("chan %p len %zu", chan, len);
2582
2583 if (!conn)
2584 return ERR_PTR(-ENOTCONN);
2585
2586 hlen = L2CAP_HDR_SIZE;
2587
2588 if (sdulen)
2589 hlen += L2CAP_SDULEN_SIZE;
2590
2591 count = min_t(unsigned int, (conn->mtu - hlen), len);
2592
2593 skb = chan->ops->alloc_skb(chan, hlen, count,
2594 msg->msg_flags & MSG_DONTWAIT);
2595 if (IS_ERR(skb))
2596 return skb;
2597
2598 /* Create L2CAP header */
2599 lh = skb_put(skb, L2CAP_HDR_SIZE);
2600 lh->cid = cpu_to_le16(chan->dcid);
2601 lh->len = cpu_to_le16(len + (hlen - L2CAP_HDR_SIZE));
2602
2603 if (sdulen)
2604 put_unaligned_le16(sdulen, skb_put(skb, L2CAP_SDULEN_SIZE));
2605
2606 err = l2cap_skbuff_fromiovec(chan, msg, len, count, skb);
2607 if (unlikely(err < 0)) {
2608 kfree_skb(skb);
2609 return ERR_PTR(err);
2610 }
2611
2612 return skb;
2613}
2614
2615static int l2cap_segment_le_sdu(struct l2cap_chan *chan,
2616 struct sk_buff_head *seg_queue,
2617 struct msghdr *msg, size_t len)
2618{
2619 struct sk_buff *skb;
2620 size_t pdu_len;
2621 u16 sdu_len;
2622
2623 BT_DBG("chan %p, msg %p, len %zu", chan, msg, len);
2624
2625 sdu_len = len;
2626 pdu_len = chan->remote_mps - L2CAP_SDULEN_SIZE;
2627
2628 while (len > 0) {
2629 if (len <= pdu_len)
2630 pdu_len = len;
2631
2632 skb = l2cap_create_le_flowctl_pdu(chan, msg, pdu_len, sdu_len);
2633 if (IS_ERR(skb)) {
2634 __skb_queue_purge(seg_queue);
2635 return PTR_ERR(skb);
2636 }
2637
2638 __skb_queue_tail(seg_queue, skb);
2639
2640 len -= pdu_len;
2641
2642 if (sdu_len) {
2643 sdu_len = 0;
2644 pdu_len += L2CAP_SDULEN_SIZE;
2645 }
2646 }
2647
2648 return 0;
2649}
2650
2651static void l2cap_le_flowctl_send(struct l2cap_chan *chan)
2652{
2653 int sent = 0;
2654
2655 BT_DBG("chan %p", chan);
2656
2657 while (chan->tx_credits && !skb_queue_empty(&chan->tx_q)) {
2658 l2cap_do_send(chan, skb_dequeue(&chan->tx_q));
2659 chan->tx_credits--;
2660 sent++;
2661 }
2662
2663 BT_DBG("Sent %d credits %u queued %u", sent, chan->tx_credits,
2664 skb_queue_len(&chan->tx_q));
2665}
2666
2667int l2cap_chan_send(struct l2cap_chan *chan, struct msghdr *msg, size_t len)
2668{
2669 struct sk_buff *skb;
2670 int err;
2671 struct sk_buff_head seg_queue;
2672
2673 if (!chan->conn)
2674 return -ENOTCONN;
2675
2676 /* Connectionless channel */
2677 if (chan->chan_type == L2CAP_CHAN_CONN_LESS) {
2678 skb = l2cap_create_connless_pdu(chan, msg, len);
2679 if (IS_ERR(skb))
2680 return PTR_ERR(skb);
2681
2682 l2cap_do_send(chan, skb);
2683 return len;
2684 }
2685
2686 switch (chan->mode) {
2687 case L2CAP_MODE_LE_FLOWCTL:
2688 case L2CAP_MODE_EXT_FLOWCTL:
2689 /* Check outgoing MTU */
2690 if (len > chan->omtu)
2691 return -EMSGSIZE;
2692
2693 __skb_queue_head_init(&seg_queue);
2694
2695 err = l2cap_segment_le_sdu(chan, &seg_queue, msg, len);
2696
2697 if (chan->state != BT_CONNECTED) {
2698 __skb_queue_purge(&seg_queue);
2699 err = -ENOTCONN;
2700 }
2701
2702 if (err)
2703 return err;
2704
2705 skb_queue_splice_tail_init(&seg_queue, &chan->tx_q);
2706
2707 l2cap_le_flowctl_send(chan);
2708
2709 if (!chan->tx_credits)
2710 chan->ops->suspend(chan);
2711
2712 err = len;
2713
2714 break;
2715
2716 case L2CAP_MODE_BASIC:
2717 /* Check outgoing MTU */
2718 if (len > chan->omtu)
2719 return -EMSGSIZE;
2720
2721 /* Create a basic PDU */
2722 skb = l2cap_create_basic_pdu(chan, msg, len);
2723 if (IS_ERR(skb))
2724 return PTR_ERR(skb);
2725
2726 l2cap_do_send(chan, skb);
2727 err = len;
2728 break;
2729
2730 case L2CAP_MODE_ERTM:
2731 case L2CAP_MODE_STREAMING:
2732 /* Check outgoing MTU */
2733 if (len > chan->omtu) {
2734 err = -EMSGSIZE;
2735 break;
2736 }
2737
2738 __skb_queue_head_init(&seg_queue);
2739
2740 /* Do segmentation before calling in to the state machine,
2741 * since it's possible to block while waiting for memory
2742 * allocation.
2743 */
2744 err = l2cap_segment_sdu(chan, &seg_queue, msg, len);
2745
2746 if (err)
2747 break;
2748
2749 if (chan->mode == L2CAP_MODE_ERTM)
2750 l2cap_tx(chan, NULL, &seg_queue, L2CAP_EV_DATA_REQUEST);
2751 else
2752 l2cap_streaming_send(chan, &seg_queue);
2753
2754 err = len;
2755
2756 /* If the skbs were not queued for sending, they'll still be in
2757 * seg_queue and need to be purged.
2758 */
2759 __skb_queue_purge(&seg_queue);
2760 break;
2761
2762 default:
2763 BT_DBG("bad state %1.1x", chan->mode);
2764 err = -EBADFD;
2765 }
2766
2767 return err;
2768}
2769EXPORT_SYMBOL_GPL(l2cap_chan_send);
2770
2771static void l2cap_send_srej(struct l2cap_chan *chan, u16 txseq)
2772{
2773 struct l2cap_ctrl control;
2774 u16 seq;
2775
2776 BT_DBG("chan %p, txseq %u", chan, txseq);
2777
2778 memset(&control, 0, sizeof(control));
2779 control.sframe = 1;
2780 control.super = L2CAP_SUPER_SREJ;
2781
2782 for (seq = chan->expected_tx_seq; seq != txseq;
2783 seq = __next_seq(chan, seq)) {
2784 if (!l2cap_ertm_seq_in_queue(&chan->srej_q, seq)) {
2785 control.reqseq = seq;
2786 l2cap_send_sframe(chan, &control);
2787 l2cap_seq_list_append(&chan->srej_list, seq);
2788 }
2789 }
2790
2791 chan->expected_tx_seq = __next_seq(chan, txseq);
2792}
2793
2794static void l2cap_send_srej_tail(struct l2cap_chan *chan)
2795{
2796 struct l2cap_ctrl control;
2797
2798 BT_DBG("chan %p", chan);
2799
2800 if (chan->srej_list.tail == L2CAP_SEQ_LIST_CLEAR)
2801 return;
2802
2803 memset(&control, 0, sizeof(control));
2804 control.sframe = 1;
2805 control.super = L2CAP_SUPER_SREJ;
2806 control.reqseq = chan->srej_list.tail;
2807 l2cap_send_sframe(chan, &control);
2808}
2809
2810static void l2cap_send_srej_list(struct l2cap_chan *chan, u16 txseq)
2811{
2812 struct l2cap_ctrl control;
2813 u16 initial_head;
2814 u16 seq;
2815
2816 BT_DBG("chan %p, txseq %u", chan, txseq);
2817
2818 memset(&control, 0, sizeof(control));
2819 control.sframe = 1;
2820 control.super = L2CAP_SUPER_SREJ;
2821
2822 /* Capture initial list head to allow only one pass through the list. */
2823 initial_head = chan->srej_list.head;
2824
2825 do {
2826 seq = l2cap_seq_list_pop(&chan->srej_list);
2827 if (seq == txseq || seq == L2CAP_SEQ_LIST_CLEAR)
2828 break;
2829
2830 control.reqseq = seq;
2831 l2cap_send_sframe(chan, &control);
2832 l2cap_seq_list_append(&chan->srej_list, seq);
2833 } while (chan->srej_list.head != initial_head);
2834}
2835
2836static void l2cap_process_reqseq(struct l2cap_chan *chan, u16 reqseq)
2837{
2838 struct sk_buff *acked_skb;
2839 u16 ackseq;
2840
2841 BT_DBG("chan %p, reqseq %u", chan, reqseq);
2842
2843 if (chan->unacked_frames == 0 || reqseq == chan->expected_ack_seq)
2844 return;
2845
2846 BT_DBG("expected_ack_seq %u, unacked_frames %u",
2847 chan->expected_ack_seq, chan->unacked_frames);
2848
2849 for (ackseq = chan->expected_ack_seq; ackseq != reqseq;
2850 ackseq = __next_seq(chan, ackseq)) {
2851
2852 acked_skb = l2cap_ertm_seq_in_queue(&chan->tx_q, ackseq);
2853 if (acked_skb) {
2854 skb_unlink(acked_skb, &chan->tx_q);
2855 kfree_skb(acked_skb);
2856 chan->unacked_frames--;
2857 }
2858 }
2859
2860 chan->expected_ack_seq = reqseq;
2861
2862 if (chan->unacked_frames == 0)
2863 __clear_retrans_timer(chan);
2864
2865 BT_DBG("unacked_frames %u", chan->unacked_frames);
2866}
2867
2868static void l2cap_abort_rx_srej_sent(struct l2cap_chan *chan)
2869{
2870 BT_DBG("chan %p", chan);
2871
2872 chan->expected_tx_seq = chan->buffer_seq;
2873 l2cap_seq_list_clear(&chan->srej_list);
2874 skb_queue_purge(&chan->srej_q);
2875 chan->rx_state = L2CAP_RX_STATE_RECV;
2876}
2877
2878static void l2cap_tx_state_xmit(struct l2cap_chan *chan,
2879 struct l2cap_ctrl *control,
2880 struct sk_buff_head *skbs, u8 event)
2881{
2882 BT_DBG("chan %p, control %p, skbs %p, event %d", chan, control, skbs,
2883 event);
2884
2885 switch (event) {
2886 case L2CAP_EV_DATA_REQUEST:
2887 if (chan->tx_send_head == NULL)
2888 chan->tx_send_head = skb_peek(skbs);
2889
2890 skb_queue_splice_tail_init(skbs, &chan->tx_q);
2891 l2cap_ertm_send(chan);
2892 break;
2893 case L2CAP_EV_LOCAL_BUSY_DETECTED:
2894 BT_DBG("Enter LOCAL_BUSY");
2895 set_bit(CONN_LOCAL_BUSY, &chan->conn_state);
2896
2897 if (chan->rx_state == L2CAP_RX_STATE_SREJ_SENT) {
2898 /* The SREJ_SENT state must be aborted if we are to
2899 * enter the LOCAL_BUSY state.
2900 */
2901 l2cap_abort_rx_srej_sent(chan);
2902 }
2903
2904 l2cap_send_ack(chan);
2905
2906 break;
2907 case L2CAP_EV_LOCAL_BUSY_CLEAR:
2908 BT_DBG("Exit LOCAL_BUSY");
2909 clear_bit(CONN_LOCAL_BUSY, &chan->conn_state);
2910
2911 if (test_bit(CONN_RNR_SENT, &chan->conn_state)) {
2912 struct l2cap_ctrl local_control;
2913
2914 memset(&local_control, 0, sizeof(local_control));
2915 local_control.sframe = 1;
2916 local_control.super = L2CAP_SUPER_RR;
2917 local_control.poll = 1;
2918 local_control.reqseq = chan->buffer_seq;
2919 l2cap_send_sframe(chan, &local_control);
2920
2921 chan->retry_count = 1;
2922 __set_monitor_timer(chan);
2923 chan->tx_state = L2CAP_TX_STATE_WAIT_F;
2924 }
2925 break;
2926 case L2CAP_EV_RECV_REQSEQ_AND_FBIT:
2927 l2cap_process_reqseq(chan, control->reqseq);
2928 break;
2929 case L2CAP_EV_EXPLICIT_POLL:
2930 l2cap_send_rr_or_rnr(chan, 1);
2931 chan->retry_count = 1;
2932 __set_monitor_timer(chan);
2933 __clear_ack_timer(chan);
2934 chan->tx_state = L2CAP_TX_STATE_WAIT_F;
2935 break;
2936 case L2CAP_EV_RETRANS_TO:
2937 l2cap_send_rr_or_rnr(chan, 1);
2938 chan->retry_count = 1;
2939 __set_monitor_timer(chan);
2940 chan->tx_state = L2CAP_TX_STATE_WAIT_F;
2941 break;
2942 case L2CAP_EV_RECV_FBIT:
2943 /* Nothing to process */
2944 break;
2945 default:
2946 break;
2947 }
2948}
2949
2950static void l2cap_tx_state_wait_f(struct l2cap_chan *chan,
2951 struct l2cap_ctrl *control,
2952 struct sk_buff_head *skbs, u8 event)
2953{
2954 BT_DBG("chan %p, control %p, skbs %p, event %d", chan, control, skbs,
2955 event);
2956
2957 switch (event) {
2958 case L2CAP_EV_DATA_REQUEST:
2959 if (chan->tx_send_head == NULL)
2960 chan->tx_send_head = skb_peek(skbs);
2961 /* Queue data, but don't send. */
2962 skb_queue_splice_tail_init(skbs, &chan->tx_q);
2963 break;
2964 case L2CAP_EV_LOCAL_BUSY_DETECTED:
2965 BT_DBG("Enter LOCAL_BUSY");
2966 set_bit(CONN_LOCAL_BUSY, &chan->conn_state);
2967
2968 if (chan->rx_state == L2CAP_RX_STATE_SREJ_SENT) {
2969 /* The SREJ_SENT state must be aborted if we are to
2970 * enter the LOCAL_BUSY state.
2971 */
2972 l2cap_abort_rx_srej_sent(chan);
2973 }
2974
2975 l2cap_send_ack(chan);
2976
2977 break;
2978 case L2CAP_EV_LOCAL_BUSY_CLEAR:
2979 BT_DBG("Exit LOCAL_BUSY");
2980 clear_bit(CONN_LOCAL_BUSY, &chan->conn_state);
2981
2982 if (test_bit(CONN_RNR_SENT, &chan->conn_state)) {
2983 struct l2cap_ctrl local_control;
2984 memset(&local_control, 0, sizeof(local_control));
2985 local_control.sframe = 1;
2986 local_control.super = L2CAP_SUPER_RR;
2987 local_control.poll = 1;
2988 local_control.reqseq = chan->buffer_seq;
2989 l2cap_send_sframe(chan, &local_control);
2990
2991 chan->retry_count = 1;
2992 __set_monitor_timer(chan);
2993 chan->tx_state = L2CAP_TX_STATE_WAIT_F;
2994 }
2995 break;
2996 case L2CAP_EV_RECV_REQSEQ_AND_FBIT:
2997 l2cap_process_reqseq(chan, control->reqseq);
2998 fallthrough;
2999
3000 case L2CAP_EV_RECV_FBIT:
3001 if (control && control->final) {
3002 __clear_monitor_timer(chan);
3003 if (chan->unacked_frames > 0)
3004 __set_retrans_timer(chan);
3005 chan->retry_count = 0;
3006 chan->tx_state = L2CAP_TX_STATE_XMIT;
3007 BT_DBG("recv fbit tx_state 0x2.2%x", chan->tx_state);
3008 }
3009 break;
3010 case L2CAP_EV_EXPLICIT_POLL:
3011 /* Ignore */
3012 break;
3013 case L2CAP_EV_MONITOR_TO:
3014 if (chan->max_tx == 0 || chan->retry_count < chan->max_tx) {
3015 l2cap_send_rr_or_rnr(chan, 1);
3016 __set_monitor_timer(chan);
3017 chan->retry_count++;
3018 } else {
3019 l2cap_send_disconn_req(chan, ECONNABORTED);
3020 }
3021 break;
3022 default:
3023 break;
3024 }
3025}
3026
3027static void l2cap_tx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
3028 struct sk_buff_head *skbs, u8 event)
3029{
3030 BT_DBG("chan %p, control %p, skbs %p, event %d, state %d",
3031 chan, control, skbs, event, chan->tx_state);
3032
3033 switch (chan->tx_state) {
3034 case L2CAP_TX_STATE_XMIT:
3035 l2cap_tx_state_xmit(chan, control, skbs, event);
3036 break;
3037 case L2CAP_TX_STATE_WAIT_F:
3038 l2cap_tx_state_wait_f(chan, control, skbs, event);
3039 break;
3040 default:
3041 /* Ignore event */
3042 break;
3043 }
3044}
3045
3046static void l2cap_pass_to_tx(struct l2cap_chan *chan,
3047 struct l2cap_ctrl *control)
3048{
3049 BT_DBG("chan %p, control %p", chan, control);
3050 l2cap_tx(chan, control, NULL, L2CAP_EV_RECV_REQSEQ_AND_FBIT);
3051}
3052
3053static void l2cap_pass_to_tx_fbit(struct l2cap_chan *chan,
3054 struct l2cap_ctrl *control)
3055{
3056 BT_DBG("chan %p, control %p", chan, control);
3057 l2cap_tx(chan, control, NULL, L2CAP_EV_RECV_FBIT);
3058}
3059
3060/* Copy frame to all raw sockets on that connection */
3061static void l2cap_raw_recv(struct l2cap_conn *conn, struct sk_buff *skb)
3062{
3063 struct sk_buff *nskb;
3064 struct l2cap_chan *chan;
3065
3066 BT_DBG("conn %p", conn);
3067
3068 mutex_lock(&conn->chan_lock);
3069
3070 list_for_each_entry(chan, &conn->chan_l, list) {
3071 if (chan->chan_type != L2CAP_CHAN_RAW)
3072 continue;
3073
3074 /* Don't send frame to the channel it came from */
3075 if (bt_cb(skb)->l2cap.chan == chan)
3076 continue;
3077
3078 nskb = skb_clone(skb, GFP_KERNEL);
3079 if (!nskb)
3080 continue;
3081 if (chan->ops->recv(chan, nskb))
3082 kfree_skb(nskb);
3083 }
3084
3085 mutex_unlock(&conn->chan_lock);
3086}
3087
3088/* ---- L2CAP signalling commands ---- */
3089static struct sk_buff *l2cap_build_cmd(struct l2cap_conn *conn, u8 code,
3090 u8 ident, u16 dlen, void *data)
3091{
3092 struct sk_buff *skb, **frag;
3093 struct l2cap_cmd_hdr *cmd;
3094 struct l2cap_hdr *lh;
3095 int len, count;
3096
3097 BT_DBG("conn %p, code 0x%2.2x, ident 0x%2.2x, len %u",
3098 conn, code, ident, dlen);
3099
3100 if (conn->mtu < L2CAP_HDR_SIZE + L2CAP_CMD_HDR_SIZE)
3101 return NULL;
3102
3103 len = L2CAP_HDR_SIZE + L2CAP_CMD_HDR_SIZE + dlen;
3104 count = min_t(unsigned int, conn->mtu, len);
3105
3106 skb = bt_skb_alloc(count, GFP_KERNEL);
3107 if (!skb)
3108 return NULL;
3109
3110 lh = skb_put(skb, L2CAP_HDR_SIZE);
3111 lh->len = cpu_to_le16(L2CAP_CMD_HDR_SIZE + dlen);
3112
3113 if (conn->hcon->type == LE_LINK)
3114 lh->cid = cpu_to_le16(L2CAP_CID_LE_SIGNALING);
3115 else
3116 lh->cid = cpu_to_le16(L2CAP_CID_SIGNALING);
3117
3118 cmd = skb_put(skb, L2CAP_CMD_HDR_SIZE);
3119 cmd->code = code;
3120 cmd->ident = ident;
3121 cmd->len = cpu_to_le16(dlen);
3122
3123 if (dlen) {
3124 count -= L2CAP_HDR_SIZE + L2CAP_CMD_HDR_SIZE;
3125 skb_put_data(skb, data, count);
3126 data += count;
3127 }
3128
3129 len -= skb->len;
3130
3131 /* Continuation fragments (no L2CAP header) */
3132 frag = &skb_shinfo(skb)->frag_list;
3133 while (len) {
3134 count = min_t(unsigned int, conn->mtu, len);
3135
3136 *frag = bt_skb_alloc(count, GFP_KERNEL);
3137 if (!*frag)
3138 goto fail;
3139
3140 skb_put_data(*frag, data, count);
3141
3142 len -= count;
3143 data += count;
3144
3145 frag = &(*frag)->next;
3146 }
3147
3148 return skb;
3149
3150fail:
3151 kfree_skb(skb);
3152 return NULL;
3153}
3154
3155static inline int l2cap_get_conf_opt(void **ptr, int *type, int *olen,
3156 unsigned long *val)
3157{
3158 struct l2cap_conf_opt *opt = *ptr;
3159 int len;
3160
3161 len = L2CAP_CONF_OPT_SIZE + opt->len;
3162 *ptr += len;
3163
3164 *type = opt->type;
3165 *olen = opt->len;
3166
3167 switch (opt->len) {
3168 case 1:
3169 *val = *((u8 *) opt->val);
3170 break;
3171
3172 case 2:
3173 *val = get_unaligned_le16(opt->val);
3174 break;
3175
3176 case 4:
3177 *val = get_unaligned_le32(opt->val);
3178 break;
3179
3180 default:
3181 *val = (unsigned long) opt->val;
3182 break;
3183 }
3184
3185 BT_DBG("type 0x%2.2x len %u val 0x%lx", *type, opt->len, *val);
3186 return len;
3187}
3188
3189static void l2cap_add_conf_opt(void **ptr, u8 type, u8 len, unsigned long val, size_t size)
3190{
3191 struct l2cap_conf_opt *opt = *ptr;
3192
3193 BT_DBG("type 0x%2.2x len %u val 0x%lx", type, len, val);
3194
3195 if (size < L2CAP_CONF_OPT_SIZE + len)
3196 return;
3197
3198 opt->type = type;
3199 opt->len = len;
3200
3201 switch (len) {
3202 case 1:
3203 *((u8 *) opt->val) = val;
3204 break;
3205
3206 case 2:
3207 put_unaligned_le16(val, opt->val);
3208 break;
3209
3210 case 4:
3211 put_unaligned_le32(val, opt->val);
3212 break;
3213
3214 default:
3215 memcpy(opt->val, (void *) val, len);
3216 break;
3217 }
3218
3219 *ptr += L2CAP_CONF_OPT_SIZE + len;
3220}
3221
3222static void l2cap_add_opt_efs(void **ptr, struct l2cap_chan *chan, size_t size)
3223{
3224 struct l2cap_conf_efs efs;
3225
3226 switch (chan->mode) {
3227 case L2CAP_MODE_ERTM:
3228 efs.id = chan->local_id;
3229 efs.stype = chan->local_stype;
3230 efs.msdu = cpu_to_le16(chan->local_msdu);
3231 efs.sdu_itime = cpu_to_le32(chan->local_sdu_itime);
3232 efs.acc_lat = cpu_to_le32(L2CAP_DEFAULT_ACC_LAT);
3233 efs.flush_to = cpu_to_le32(L2CAP_EFS_DEFAULT_FLUSH_TO);
3234 break;
3235
3236 case L2CAP_MODE_STREAMING:
3237 efs.id = 1;
3238 efs.stype = L2CAP_SERV_BESTEFFORT;
3239 efs.msdu = cpu_to_le16(chan->local_msdu);
3240 efs.sdu_itime = cpu_to_le32(chan->local_sdu_itime);
3241 efs.acc_lat = 0;
3242 efs.flush_to = 0;
3243 break;
3244
3245 default:
3246 return;
3247 }
3248
3249 l2cap_add_conf_opt(ptr, L2CAP_CONF_EFS, sizeof(efs),
3250 (unsigned long) &efs, size);
3251}
3252
3253static void l2cap_ack_timeout(struct work_struct *work)
3254{
3255 struct l2cap_chan *chan = container_of(work, struct l2cap_chan,
3256 ack_timer.work);
3257 u16 frames_to_ack;
3258
3259 BT_DBG("chan %p", chan);
3260
3261 l2cap_chan_lock(chan);
3262
3263 frames_to_ack = __seq_offset(chan, chan->buffer_seq,
3264 chan->last_acked_seq);
3265
3266 if (frames_to_ack)
3267 l2cap_send_rr_or_rnr(chan, 0);
3268
3269 l2cap_chan_unlock(chan);
3270 l2cap_chan_put(chan);
3271}
3272
3273int l2cap_ertm_init(struct l2cap_chan *chan)
3274{
3275 int err;
3276
3277 chan->next_tx_seq = 0;
3278 chan->expected_tx_seq = 0;
3279 chan->expected_ack_seq = 0;
3280 chan->unacked_frames = 0;
3281 chan->buffer_seq = 0;
3282 chan->frames_sent = 0;
3283 chan->last_acked_seq = 0;
3284 chan->sdu = NULL;
3285 chan->sdu_last_frag = NULL;
3286 chan->sdu_len = 0;
3287
3288 skb_queue_head_init(&chan->tx_q);
3289
3290 chan->local_amp_id = AMP_ID_BREDR;
3291 chan->move_id = AMP_ID_BREDR;
3292 chan->move_state = L2CAP_MOVE_STABLE;
3293 chan->move_role = L2CAP_MOVE_ROLE_NONE;
3294
3295 if (chan->mode != L2CAP_MODE_ERTM)
3296 return 0;
3297
3298 chan->rx_state = L2CAP_RX_STATE_RECV;
3299 chan->tx_state = L2CAP_TX_STATE_XMIT;
3300
3301 skb_queue_head_init(&chan->srej_q);
3302
3303 err = l2cap_seq_list_init(&chan->srej_list, chan->tx_win);
3304 if (err < 0)
3305 return err;
3306
3307 err = l2cap_seq_list_init(&chan->retrans_list, chan->remote_tx_win);
3308 if (err < 0)
3309 l2cap_seq_list_free(&chan->srej_list);
3310
3311 return err;
3312}
3313
3314static inline __u8 l2cap_select_mode(__u8 mode, __u16 remote_feat_mask)
3315{
3316 switch (mode) {
3317 case L2CAP_MODE_STREAMING:
3318 case L2CAP_MODE_ERTM:
3319 if (l2cap_mode_supported(mode, remote_feat_mask))
3320 return mode;
3321 fallthrough;
3322 default:
3323 return L2CAP_MODE_BASIC;
3324 }
3325}
3326
3327static inline bool __l2cap_ews_supported(struct l2cap_conn *conn)
3328{
3329 return ((conn->local_fixed_chan & L2CAP_FC_A2MP) &&
3330 (conn->feat_mask & L2CAP_FEAT_EXT_WINDOW));
3331}
3332
3333static inline bool __l2cap_efs_supported(struct l2cap_conn *conn)
3334{
3335 return ((conn->local_fixed_chan & L2CAP_FC_A2MP) &&
3336 (conn->feat_mask & L2CAP_FEAT_EXT_FLOW));
3337}
3338
3339static void __l2cap_set_ertm_timeouts(struct l2cap_chan *chan,
3340 struct l2cap_conf_rfc *rfc)
3341{
3342 if (chan->local_amp_id != AMP_ID_BREDR && chan->hs_hcon) {
3343 u64 ertm_to = chan->hs_hcon->hdev->amp_be_flush_to;
3344
3345 /* Class 1 devices have must have ERTM timeouts
3346 * exceeding the Link Supervision Timeout. The
3347 * default Link Supervision Timeout for AMP
3348 * controllers is 10 seconds.
3349 *
3350 * Class 1 devices use 0xffffffff for their
3351 * best-effort flush timeout, so the clamping logic
3352 * will result in a timeout that meets the above
3353 * requirement. ERTM timeouts are 16-bit values, so
3354 * the maximum timeout is 65.535 seconds.
3355 */
3356
3357 /* Convert timeout to milliseconds and round */
3358 ertm_to = DIV_ROUND_UP_ULL(ertm_to, 1000);
3359
3360 /* This is the recommended formula for class 2 devices
3361 * that start ERTM timers when packets are sent to the
3362 * controller.
3363 */
3364 ertm_to = 3 * ertm_to + 500;
3365
3366 if (ertm_to > 0xffff)
3367 ertm_to = 0xffff;
3368
3369 rfc->retrans_timeout = cpu_to_le16((u16) ertm_to);
3370 rfc->monitor_timeout = rfc->retrans_timeout;
3371 } else {
3372 rfc->retrans_timeout = cpu_to_le16(L2CAP_DEFAULT_RETRANS_TO);
3373 rfc->monitor_timeout = cpu_to_le16(L2CAP_DEFAULT_MONITOR_TO);
3374 }
3375}
3376
3377static inline void l2cap_txwin_setup(struct l2cap_chan *chan)
3378{
3379 if (chan->tx_win > L2CAP_DEFAULT_TX_WINDOW &&
3380 __l2cap_ews_supported(chan->conn)) {
3381 /* use extended control field */
3382 set_bit(FLAG_EXT_CTRL, &chan->flags);
3383 chan->tx_win_max = L2CAP_DEFAULT_EXT_WINDOW;
3384 } else {
3385 chan->tx_win = min_t(u16, chan->tx_win,
3386 L2CAP_DEFAULT_TX_WINDOW);
3387 chan->tx_win_max = L2CAP_DEFAULT_TX_WINDOW;
3388 }
3389 chan->ack_win = chan->tx_win;
3390}
3391
3392static void l2cap_mtu_auto(struct l2cap_chan *chan)
3393{
3394 struct hci_conn *conn = chan->conn->hcon;
3395
3396 chan->imtu = L2CAP_DEFAULT_MIN_MTU;
3397
3398 /* The 2-DH1 packet has between 2 and 56 information bytes
3399 * (including the 2-byte payload header)
3400 */
3401 if (!(conn->pkt_type & HCI_2DH1))
3402 chan->imtu = 54;
3403
3404 /* The 3-DH1 packet has between 2 and 85 information bytes
3405 * (including the 2-byte payload header)
3406 */
3407 if (!(conn->pkt_type & HCI_3DH1))
3408 chan->imtu = 83;
3409
3410 /* The 2-DH3 packet has between 2 and 369 information bytes
3411 * (including the 2-byte payload header)
3412 */
3413 if (!(conn->pkt_type & HCI_2DH3))
3414 chan->imtu = 367;
3415
3416 /* The 3-DH3 packet has between 2 and 554 information bytes
3417 * (including the 2-byte payload header)
3418 */
3419 if (!(conn->pkt_type & HCI_3DH3))
3420 chan->imtu = 552;
3421
3422 /* The 2-DH5 packet has between 2 and 681 information bytes
3423 * (including the 2-byte payload header)
3424 */
3425 if (!(conn->pkt_type & HCI_2DH5))
3426 chan->imtu = 679;
3427
3428 /* The 3-DH5 packet has between 2 and 1023 information bytes
3429 * (including the 2-byte payload header)
3430 */
3431 if (!(conn->pkt_type & HCI_3DH5))
3432 chan->imtu = 1021;
3433}
3434
3435static int l2cap_build_conf_req(struct l2cap_chan *chan, void *data, size_t data_size)
3436{
3437 struct l2cap_conf_req *req = data;
3438 struct l2cap_conf_rfc rfc = { .mode = chan->mode };
3439 void *ptr = req->data;
3440 void *endptr = data + data_size;
3441 u16 size;
3442
3443 BT_DBG("chan %p", chan);
3444
3445 if (chan->num_conf_req || chan->num_conf_rsp)
3446 goto done;
3447
3448 switch (chan->mode) {
3449 case L2CAP_MODE_STREAMING:
3450 case L2CAP_MODE_ERTM:
3451 if (test_bit(CONF_STATE2_DEVICE, &chan->conf_state))
3452 break;
3453
3454 if (__l2cap_efs_supported(chan->conn))
3455 set_bit(FLAG_EFS_ENABLE, &chan->flags);
3456
3457 fallthrough;
3458 default:
3459 chan->mode = l2cap_select_mode(rfc.mode, chan->conn->feat_mask);
3460 break;
3461 }
3462
3463done:
3464 if (chan->imtu != L2CAP_DEFAULT_MTU) {
3465 if (!chan->imtu)
3466 l2cap_mtu_auto(chan);
3467 l2cap_add_conf_opt(&ptr, L2CAP_CONF_MTU, 2, chan->imtu,
3468 endptr - ptr);
3469 }
3470
3471 switch (chan->mode) {
3472 case L2CAP_MODE_BASIC:
3473 if (disable_ertm)
3474 break;
3475
3476 if (!(chan->conn->feat_mask & L2CAP_FEAT_ERTM) &&
3477 !(chan->conn->feat_mask & L2CAP_FEAT_STREAMING))
3478 break;
3479
3480 rfc.mode = L2CAP_MODE_BASIC;
3481 rfc.txwin_size = 0;
3482 rfc.max_transmit = 0;
3483 rfc.retrans_timeout = 0;
3484 rfc.monitor_timeout = 0;
3485 rfc.max_pdu_size = 0;
3486
3487 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3488 (unsigned long) &rfc, endptr - ptr);
3489 break;
3490
3491 case L2CAP_MODE_ERTM:
3492 rfc.mode = L2CAP_MODE_ERTM;
3493 rfc.max_transmit = chan->max_tx;
3494
3495 __l2cap_set_ertm_timeouts(chan, &rfc);
3496
3497 size = min_t(u16, L2CAP_DEFAULT_MAX_PDU_SIZE, chan->conn->mtu -
3498 L2CAP_EXT_HDR_SIZE - L2CAP_SDULEN_SIZE -
3499 L2CAP_FCS_SIZE);
3500 rfc.max_pdu_size = cpu_to_le16(size);
3501
3502 l2cap_txwin_setup(chan);
3503
3504 rfc.txwin_size = min_t(u16, chan->tx_win,
3505 L2CAP_DEFAULT_TX_WINDOW);
3506
3507 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3508 (unsigned long) &rfc, endptr - ptr);
3509
3510 if (test_bit(FLAG_EFS_ENABLE, &chan->flags))
3511 l2cap_add_opt_efs(&ptr, chan, endptr - ptr);
3512
3513 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
3514 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EWS, 2,
3515 chan->tx_win, endptr - ptr);
3516
3517 if (chan->conn->feat_mask & L2CAP_FEAT_FCS)
3518 if (chan->fcs == L2CAP_FCS_NONE ||
3519 test_bit(CONF_RECV_NO_FCS, &chan->conf_state)) {
3520 chan->fcs = L2CAP_FCS_NONE;
3521 l2cap_add_conf_opt(&ptr, L2CAP_CONF_FCS, 1,
3522 chan->fcs, endptr - ptr);
3523 }
3524 break;
3525
3526 case L2CAP_MODE_STREAMING:
3527 l2cap_txwin_setup(chan);
3528 rfc.mode = L2CAP_MODE_STREAMING;
3529 rfc.txwin_size = 0;
3530 rfc.max_transmit = 0;
3531 rfc.retrans_timeout = 0;
3532 rfc.monitor_timeout = 0;
3533
3534 size = min_t(u16, L2CAP_DEFAULT_MAX_PDU_SIZE, chan->conn->mtu -
3535 L2CAP_EXT_HDR_SIZE - L2CAP_SDULEN_SIZE -
3536 L2CAP_FCS_SIZE);
3537 rfc.max_pdu_size = cpu_to_le16(size);
3538
3539 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3540 (unsigned long) &rfc, endptr - ptr);
3541
3542 if (test_bit(FLAG_EFS_ENABLE, &chan->flags))
3543 l2cap_add_opt_efs(&ptr, chan, endptr - ptr);
3544
3545 if (chan->conn->feat_mask & L2CAP_FEAT_FCS)
3546 if (chan->fcs == L2CAP_FCS_NONE ||
3547 test_bit(CONF_RECV_NO_FCS, &chan->conf_state)) {
3548 chan->fcs = L2CAP_FCS_NONE;
3549 l2cap_add_conf_opt(&ptr, L2CAP_CONF_FCS, 1,
3550 chan->fcs, endptr - ptr);
3551 }
3552 break;
3553 }
3554
3555 req->dcid = cpu_to_le16(chan->dcid);
3556 req->flags = cpu_to_le16(0);
3557
3558 return ptr - data;
3559}
3560
3561static int l2cap_parse_conf_req(struct l2cap_chan *chan, void *data, size_t data_size)
3562{
3563 struct l2cap_conf_rsp *rsp = data;
3564 void *ptr = rsp->data;
3565 void *endptr = data + data_size;
3566 void *req = chan->conf_req;
3567 int len = chan->conf_len;
3568 int type, hint, olen;
3569 unsigned long val;
3570 struct l2cap_conf_rfc rfc = { .mode = L2CAP_MODE_BASIC };
3571 struct l2cap_conf_efs efs;
3572 u8 remote_efs = 0;
3573 u16 mtu = L2CAP_DEFAULT_MTU;
3574 u16 result = L2CAP_CONF_SUCCESS;
3575 u16 size;
3576
3577 BT_DBG("chan %p", chan);
3578
3579 while (len >= L2CAP_CONF_OPT_SIZE) {
3580 len -= l2cap_get_conf_opt(&req, &type, &olen, &val);
3581 if (len < 0)
3582 break;
3583
3584 hint = type & L2CAP_CONF_HINT;
3585 type &= L2CAP_CONF_MASK;
3586
3587 switch (type) {
3588 case L2CAP_CONF_MTU:
3589 if (olen != 2)
3590 break;
3591 mtu = val;
3592 break;
3593
3594 case L2CAP_CONF_FLUSH_TO:
3595 if (olen != 2)
3596 break;
3597 chan->flush_to = val;
3598 break;
3599
3600 case L2CAP_CONF_QOS:
3601 break;
3602
3603 case L2CAP_CONF_RFC:
3604 if (olen != sizeof(rfc))
3605 break;
3606 memcpy(&rfc, (void *) val, olen);
3607 break;
3608
3609 case L2CAP_CONF_FCS:
3610 if (olen != 1)
3611 break;
3612 if (val == L2CAP_FCS_NONE)
3613 set_bit(CONF_RECV_NO_FCS, &chan->conf_state);
3614 break;
3615
3616 case L2CAP_CONF_EFS:
3617 if (olen != sizeof(efs))
3618 break;
3619 remote_efs = 1;
3620 memcpy(&efs, (void *) val, olen);
3621 break;
3622
3623 case L2CAP_CONF_EWS:
3624 if (olen != 2)
3625 break;
3626 if (!(chan->conn->local_fixed_chan & L2CAP_FC_A2MP))
3627 return -ECONNREFUSED;
3628 set_bit(FLAG_EXT_CTRL, &chan->flags);
3629 set_bit(CONF_EWS_RECV, &chan->conf_state);
3630 chan->tx_win_max = L2CAP_DEFAULT_EXT_WINDOW;
3631 chan->remote_tx_win = val;
3632 break;
3633
3634 default:
3635 if (hint)
3636 break;
3637 result = L2CAP_CONF_UNKNOWN;
3638 l2cap_add_conf_opt(&ptr, (u8)type, sizeof(u8), type, endptr - ptr);
3639 break;
3640 }
3641 }
3642
3643 if (chan->num_conf_rsp || chan->num_conf_req > 1)
3644 goto done;
3645
3646 switch (chan->mode) {
3647 case L2CAP_MODE_STREAMING:
3648 case L2CAP_MODE_ERTM:
3649 if (!test_bit(CONF_STATE2_DEVICE, &chan->conf_state)) {
3650 chan->mode = l2cap_select_mode(rfc.mode,
3651 chan->conn->feat_mask);
3652 break;
3653 }
3654
3655 if (remote_efs) {
3656 if (__l2cap_efs_supported(chan->conn))
3657 set_bit(FLAG_EFS_ENABLE, &chan->flags);
3658 else
3659 return -ECONNREFUSED;
3660 }
3661
3662 if (chan->mode != rfc.mode)
3663 return -ECONNREFUSED;
3664
3665 break;
3666 }
3667
3668done:
3669 if (chan->mode != rfc.mode) {
3670 result = L2CAP_CONF_UNACCEPT;
3671 rfc.mode = chan->mode;
3672
3673 if (chan->num_conf_rsp == 1)
3674 return -ECONNREFUSED;
3675
3676 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3677 (unsigned long) &rfc, endptr - ptr);
3678 }
3679
3680 if (result == L2CAP_CONF_SUCCESS) {
3681 /* Configure output options and let the other side know
3682 * which ones we don't like. */
3683
3684 if (mtu < L2CAP_DEFAULT_MIN_MTU)
3685 result = L2CAP_CONF_UNACCEPT;
3686 else {
3687 chan->omtu = mtu;
3688 set_bit(CONF_MTU_DONE, &chan->conf_state);
3689 }
3690 l2cap_add_conf_opt(&ptr, L2CAP_CONF_MTU, 2, chan->omtu, endptr - ptr);
3691
3692 if (remote_efs) {
3693 if (chan->local_stype != L2CAP_SERV_NOTRAFIC &&
3694 efs.stype != L2CAP_SERV_NOTRAFIC &&
3695 efs.stype != chan->local_stype) {
3696
3697 result = L2CAP_CONF_UNACCEPT;
3698
3699 if (chan->num_conf_req >= 1)
3700 return -ECONNREFUSED;
3701
3702 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EFS,
3703 sizeof(efs),
3704 (unsigned long) &efs, endptr - ptr);
3705 } else {
3706 /* Send PENDING Conf Rsp */
3707 result = L2CAP_CONF_PENDING;
3708 set_bit(CONF_LOC_CONF_PEND, &chan->conf_state);
3709 }
3710 }
3711
3712 switch (rfc.mode) {
3713 case L2CAP_MODE_BASIC:
3714 chan->fcs = L2CAP_FCS_NONE;
3715 set_bit(CONF_MODE_DONE, &chan->conf_state);
3716 break;
3717
3718 case L2CAP_MODE_ERTM:
3719 if (!test_bit(CONF_EWS_RECV, &chan->conf_state))
3720 chan->remote_tx_win = rfc.txwin_size;
3721 else
3722 rfc.txwin_size = L2CAP_DEFAULT_TX_WINDOW;
3723
3724 chan->remote_max_tx = rfc.max_transmit;
3725
3726 size = min_t(u16, le16_to_cpu(rfc.max_pdu_size),
3727 chan->conn->mtu - L2CAP_EXT_HDR_SIZE -
3728 L2CAP_SDULEN_SIZE - L2CAP_FCS_SIZE);
3729 rfc.max_pdu_size = cpu_to_le16(size);
3730 chan->remote_mps = size;
3731
3732 __l2cap_set_ertm_timeouts(chan, &rfc);
3733
3734 set_bit(CONF_MODE_DONE, &chan->conf_state);
3735
3736 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC,
3737 sizeof(rfc), (unsigned long) &rfc, endptr - ptr);
3738
3739 if (remote_efs &&
3740 test_bit(FLAG_EFS_ENABLE, &chan->flags)) {
3741 chan->remote_id = efs.id;
3742 chan->remote_stype = efs.stype;
3743 chan->remote_msdu = le16_to_cpu(efs.msdu);
3744 chan->remote_flush_to =
3745 le32_to_cpu(efs.flush_to);
3746 chan->remote_acc_lat =
3747 le32_to_cpu(efs.acc_lat);
3748 chan->remote_sdu_itime =
3749 le32_to_cpu(efs.sdu_itime);
3750 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EFS,
3751 sizeof(efs),
3752 (unsigned long) &efs, endptr - ptr);
3753 }
3754 break;
3755
3756 case L2CAP_MODE_STREAMING:
3757 size = min_t(u16, le16_to_cpu(rfc.max_pdu_size),
3758 chan->conn->mtu - L2CAP_EXT_HDR_SIZE -
3759 L2CAP_SDULEN_SIZE - L2CAP_FCS_SIZE);
3760 rfc.max_pdu_size = cpu_to_le16(size);
3761 chan->remote_mps = size;
3762
3763 set_bit(CONF_MODE_DONE, &chan->conf_state);
3764
3765 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3766 (unsigned long) &rfc, endptr - ptr);
3767
3768 break;
3769
3770 default:
3771 result = L2CAP_CONF_UNACCEPT;
3772
3773 memset(&rfc, 0, sizeof(rfc));
3774 rfc.mode = chan->mode;
3775 }
3776
3777 if (result == L2CAP_CONF_SUCCESS)
3778 set_bit(CONF_OUTPUT_DONE, &chan->conf_state);
3779 }
3780 rsp->scid = cpu_to_le16(chan->dcid);
3781 rsp->result = cpu_to_le16(result);
3782 rsp->flags = cpu_to_le16(0);
3783
3784 return ptr - data;
3785}
3786
3787static int l2cap_parse_conf_rsp(struct l2cap_chan *chan, void *rsp, int len,
3788 void *data, size_t size, u16 *result)
3789{
3790 struct l2cap_conf_req *req = data;
3791 void *ptr = req->data;
3792 void *endptr = data + size;
3793 int type, olen;
3794 unsigned long val;
3795 struct l2cap_conf_rfc rfc = { .mode = L2CAP_MODE_BASIC };
3796 struct l2cap_conf_efs efs;
3797
3798 BT_DBG("chan %p, rsp %p, len %d, req %p", chan, rsp, len, data);
3799
3800 while (len >= L2CAP_CONF_OPT_SIZE) {
3801 len -= l2cap_get_conf_opt(&rsp, &type, &olen, &val);
3802 if (len < 0)
3803 break;
3804
3805 switch (type) {
3806 case L2CAP_CONF_MTU:
3807 if (olen != 2)
3808 break;
3809 if (val < L2CAP_DEFAULT_MIN_MTU) {
3810 *result = L2CAP_CONF_UNACCEPT;
3811 chan->imtu = L2CAP_DEFAULT_MIN_MTU;
3812 } else
3813 chan->imtu = val;
3814 l2cap_add_conf_opt(&ptr, L2CAP_CONF_MTU, 2, chan->imtu,
3815 endptr - ptr);
3816 break;
3817
3818 case L2CAP_CONF_FLUSH_TO:
3819 if (olen != 2)
3820 break;
3821 chan->flush_to = val;
3822 l2cap_add_conf_opt(&ptr, L2CAP_CONF_FLUSH_TO, 2,
3823 chan->flush_to, endptr - ptr);
3824 break;
3825
3826 case L2CAP_CONF_RFC:
3827 if (olen != sizeof(rfc))
3828 break;
3829 memcpy(&rfc, (void *)val, olen);
3830 if (test_bit(CONF_STATE2_DEVICE, &chan->conf_state) &&
3831 rfc.mode != chan->mode)
3832 return -ECONNREFUSED;
3833 chan->fcs = 0;
3834 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3835 (unsigned long) &rfc, endptr - ptr);
3836 break;
3837
3838 case L2CAP_CONF_EWS:
3839 if (olen != 2)
3840 break;
3841 chan->ack_win = min_t(u16, val, chan->ack_win);
3842 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EWS, 2,
3843 chan->tx_win, endptr - ptr);
3844 break;
3845
3846 case L2CAP_CONF_EFS:
3847 if (olen != sizeof(efs))
3848 break;
3849 memcpy(&efs, (void *)val, olen);
3850 if (chan->local_stype != L2CAP_SERV_NOTRAFIC &&
3851 efs.stype != L2CAP_SERV_NOTRAFIC &&
3852 efs.stype != chan->local_stype)
3853 return -ECONNREFUSED;
3854 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EFS, sizeof(efs),
3855 (unsigned long) &efs, endptr - ptr);
3856 break;
3857
3858 case L2CAP_CONF_FCS:
3859 if (olen != 1)
3860 break;
3861 if (*result == L2CAP_CONF_PENDING)
3862 if (val == L2CAP_FCS_NONE)
3863 set_bit(CONF_RECV_NO_FCS,
3864 &chan->conf_state);
3865 break;
3866 }
3867 }
3868
3869 if (chan->mode == L2CAP_MODE_BASIC && chan->mode != rfc.mode)
3870 return -ECONNREFUSED;
3871
3872 chan->mode = rfc.mode;
3873
3874 if (*result == L2CAP_CONF_SUCCESS || *result == L2CAP_CONF_PENDING) {
3875 switch (rfc.mode) {
3876 case L2CAP_MODE_ERTM:
3877 chan->retrans_timeout = le16_to_cpu(rfc.retrans_timeout);
3878 chan->monitor_timeout = le16_to_cpu(rfc.monitor_timeout);
3879 chan->mps = le16_to_cpu(rfc.max_pdu_size);
3880 if (!test_bit(FLAG_EXT_CTRL, &chan->flags))
3881 chan->ack_win = min_t(u16, chan->ack_win,
3882 rfc.txwin_size);
3883
3884 if (test_bit(FLAG_EFS_ENABLE, &chan->flags)) {
3885 chan->local_msdu = le16_to_cpu(efs.msdu);
3886 chan->local_sdu_itime =
3887 le32_to_cpu(efs.sdu_itime);
3888 chan->local_acc_lat = le32_to_cpu(efs.acc_lat);
3889 chan->local_flush_to =
3890 le32_to_cpu(efs.flush_to);
3891 }
3892 break;
3893
3894 case L2CAP_MODE_STREAMING:
3895 chan->mps = le16_to_cpu(rfc.max_pdu_size);
3896 }
3897 }
3898
3899 req->dcid = cpu_to_le16(chan->dcid);
3900 req->flags = cpu_to_le16(0);
3901
3902 return ptr - data;
3903}
3904
3905static int l2cap_build_conf_rsp(struct l2cap_chan *chan, void *data,
3906 u16 result, u16 flags)
3907{
3908 struct l2cap_conf_rsp *rsp = data;
3909 void *ptr = rsp->data;
3910
3911 BT_DBG("chan %p", chan);
3912
3913 rsp->scid = cpu_to_le16(chan->dcid);
3914 rsp->result = cpu_to_le16(result);
3915 rsp->flags = cpu_to_le16(flags);
3916
3917 return ptr - data;
3918}
3919
3920void __l2cap_le_connect_rsp_defer(struct l2cap_chan *chan)
3921{
3922 struct l2cap_le_conn_rsp rsp;
3923 struct l2cap_conn *conn = chan->conn;
3924
3925 BT_DBG("chan %p", chan);
3926
3927 rsp.dcid = cpu_to_le16(chan->scid);
3928 rsp.mtu = cpu_to_le16(chan->imtu);
3929 rsp.mps = cpu_to_le16(chan->mps);
3930 rsp.credits = cpu_to_le16(chan->rx_credits);
3931 rsp.result = cpu_to_le16(L2CAP_CR_LE_SUCCESS);
3932
3933 l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CONN_RSP, sizeof(rsp),
3934 &rsp);
3935}
3936
3937static void l2cap_ecred_list_defer(struct l2cap_chan *chan, void *data)
3938{
3939 int *result = data;
3940
3941 if (*result || test_bit(FLAG_ECRED_CONN_REQ_SENT, &chan->flags))
3942 return;
3943
3944 switch (chan->state) {
3945 case BT_CONNECT2:
3946 /* If channel still pending accept add to result */
3947 (*result)++;
3948 return;
3949 case BT_CONNECTED:
3950 return;
3951 default:
3952 /* If not connected or pending accept it has been refused */
3953 *result = -ECONNREFUSED;
3954 return;
3955 }
3956}
3957
3958struct l2cap_ecred_rsp_data {
3959 struct {
3960 struct l2cap_ecred_conn_rsp rsp;
3961 __le16 scid[L2CAP_ECRED_MAX_CID];
3962 } __packed pdu;
3963 int count;
3964};
3965
3966static void l2cap_ecred_rsp_defer(struct l2cap_chan *chan, void *data)
3967{
3968 struct l2cap_ecred_rsp_data *rsp = data;
3969
3970 if (test_bit(FLAG_ECRED_CONN_REQ_SENT, &chan->flags))
3971 return;
3972
3973 /* Reset ident so only one response is sent */
3974 chan->ident = 0;
3975
3976 /* Include all channels pending with the same ident */
3977 if (!rsp->pdu.rsp.result)
3978 rsp->pdu.rsp.dcid[rsp->count++] = cpu_to_le16(chan->scid);
3979 else
3980 l2cap_chan_del(chan, ECONNRESET);
3981}
3982
3983void __l2cap_ecred_conn_rsp_defer(struct l2cap_chan *chan)
3984{
3985 struct l2cap_conn *conn = chan->conn;
3986 struct l2cap_ecred_rsp_data data;
3987 u16 id = chan->ident;
3988 int result = 0;
3989
3990 if (!id)
3991 return;
3992
3993 BT_DBG("chan %p id %d", chan, id);
3994
3995 memset(&data, 0, sizeof(data));
3996
3997 data.pdu.rsp.mtu = cpu_to_le16(chan->imtu);
3998 data.pdu.rsp.mps = cpu_to_le16(chan->mps);
3999 data.pdu.rsp.credits = cpu_to_le16(chan->rx_credits);
4000 data.pdu.rsp.result = cpu_to_le16(L2CAP_CR_LE_SUCCESS);
4001
4002 /* Verify that all channels are ready */
4003 __l2cap_chan_list_id(conn, id, l2cap_ecred_list_defer, &result);
4004
4005 if (result > 0)
4006 return;
4007
4008 if (result < 0)
4009 data.pdu.rsp.result = cpu_to_le16(L2CAP_CR_LE_AUTHORIZATION);
4010
4011 /* Build response */
4012 __l2cap_chan_list_id(conn, id, l2cap_ecred_rsp_defer, &data);
4013
4014 l2cap_send_cmd(conn, id, L2CAP_ECRED_CONN_RSP,
4015 sizeof(data.pdu.rsp) + (data.count * sizeof(__le16)),
4016 &data.pdu);
4017}
4018
4019void __l2cap_connect_rsp_defer(struct l2cap_chan *chan)
4020{
4021 struct l2cap_conn_rsp rsp;
4022 struct l2cap_conn *conn = chan->conn;
4023 u8 buf[128];
4024 u8 rsp_code;
4025
4026 rsp.scid = cpu_to_le16(chan->dcid);
4027 rsp.dcid = cpu_to_le16(chan->scid);
4028 rsp.result = cpu_to_le16(L2CAP_CR_SUCCESS);
4029 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
4030
4031 if (chan->hs_hcon)
4032 rsp_code = L2CAP_CREATE_CHAN_RSP;
4033 else
4034 rsp_code = L2CAP_CONN_RSP;
4035
4036 BT_DBG("chan %p rsp_code %u", chan, rsp_code);
4037
4038 l2cap_send_cmd(conn, chan->ident, rsp_code, sizeof(rsp), &rsp);
4039
4040 if (test_and_set_bit(CONF_REQ_SENT, &chan->conf_state))
4041 return;
4042
4043 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
4044 l2cap_build_conf_req(chan, buf, sizeof(buf)), buf);
4045 chan->num_conf_req++;
4046}
4047
4048static void l2cap_conf_rfc_get(struct l2cap_chan *chan, void *rsp, int len)
4049{
4050 int type, olen;
4051 unsigned long val;
4052 /* Use sane default values in case a misbehaving remote device
4053 * did not send an RFC or extended window size option.
4054 */
4055 u16 txwin_ext = chan->ack_win;
4056 struct l2cap_conf_rfc rfc = {
4057 .mode = chan->mode,
4058 .retrans_timeout = cpu_to_le16(L2CAP_DEFAULT_RETRANS_TO),
4059 .monitor_timeout = cpu_to_le16(L2CAP_DEFAULT_MONITOR_TO),
4060 .max_pdu_size = cpu_to_le16(chan->imtu),
4061 .txwin_size = min_t(u16, chan->ack_win, L2CAP_DEFAULT_TX_WINDOW),
4062 };
4063
4064 BT_DBG("chan %p, rsp %p, len %d", chan, rsp, len);
4065
4066 if ((chan->mode != L2CAP_MODE_ERTM) && (chan->mode != L2CAP_MODE_STREAMING))
4067 return;
4068
4069 while (len >= L2CAP_CONF_OPT_SIZE) {
4070 len -= l2cap_get_conf_opt(&rsp, &type, &olen, &val);
4071 if (len < 0)
4072 break;
4073
4074 switch (type) {
4075 case L2CAP_CONF_RFC:
4076 if (olen != sizeof(rfc))
4077 break;
4078 memcpy(&rfc, (void *)val, olen);
4079 break;
4080 case L2CAP_CONF_EWS:
4081 if (olen != 2)
4082 break;
4083 txwin_ext = val;
4084 break;
4085 }
4086 }
4087
4088 switch (rfc.mode) {
4089 case L2CAP_MODE_ERTM:
4090 chan->retrans_timeout = le16_to_cpu(rfc.retrans_timeout);
4091 chan->monitor_timeout = le16_to_cpu(rfc.monitor_timeout);
4092 chan->mps = le16_to_cpu(rfc.max_pdu_size);
4093 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
4094 chan->ack_win = min_t(u16, chan->ack_win, txwin_ext);
4095 else
4096 chan->ack_win = min_t(u16, chan->ack_win,
4097 rfc.txwin_size);
4098 break;
4099 case L2CAP_MODE_STREAMING:
4100 chan->mps = le16_to_cpu(rfc.max_pdu_size);
4101 }
4102}
4103
4104static inline int l2cap_command_rej(struct l2cap_conn *conn,
4105 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4106 u8 *data)
4107{
4108 struct l2cap_cmd_rej_unk *rej = (struct l2cap_cmd_rej_unk *) data;
4109
4110 if (cmd_len < sizeof(*rej))
4111 return -EPROTO;
4112
4113 if (rej->reason != L2CAP_REJ_NOT_UNDERSTOOD)
4114 return 0;
4115
4116 if ((conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT) &&
4117 cmd->ident == conn->info_ident) {
4118 cancel_delayed_work(&conn->info_timer);
4119
4120 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
4121 conn->info_ident = 0;
4122
4123 l2cap_conn_start(conn);
4124 }
4125
4126 return 0;
4127}
4128
4129static struct l2cap_chan *l2cap_connect(struct l2cap_conn *conn,
4130 struct l2cap_cmd_hdr *cmd,
4131 u8 *data, u8 rsp_code, u8 amp_id)
4132{
4133 struct l2cap_conn_req *req = (struct l2cap_conn_req *) data;
4134 struct l2cap_conn_rsp rsp;
4135 struct l2cap_chan *chan = NULL, *pchan;
4136 int result, status = L2CAP_CS_NO_INFO;
4137
4138 u16 dcid = 0, scid = __le16_to_cpu(req->scid);
4139 __le16 psm = req->psm;
4140
4141 BT_DBG("psm 0x%2.2x scid 0x%4.4x", __le16_to_cpu(psm), scid);
4142
4143 /* Check if we have socket listening on psm */
4144 pchan = l2cap_global_chan_by_psm(BT_LISTEN, psm, &conn->hcon->src,
4145 &conn->hcon->dst, ACL_LINK);
4146 if (!pchan) {
4147 result = L2CAP_CR_BAD_PSM;
4148 goto sendresp;
4149 }
4150
4151 mutex_lock(&conn->chan_lock);
4152 l2cap_chan_lock(pchan);
4153
4154 /* Check if the ACL is secure enough (if not SDP) */
4155 if (psm != cpu_to_le16(L2CAP_PSM_SDP) &&
4156 !hci_conn_check_link_mode(conn->hcon)) {
4157 conn->disc_reason = HCI_ERROR_AUTH_FAILURE;
4158 result = L2CAP_CR_SEC_BLOCK;
4159 goto response;
4160 }
4161
4162 result = L2CAP_CR_NO_MEM;
4163
4164 /* Check for valid dynamic CID range (as per Erratum 3253) */
4165 if (scid < L2CAP_CID_DYN_START || scid > L2CAP_CID_DYN_END) {
4166 result = L2CAP_CR_INVALID_SCID;
4167 goto response;
4168 }
4169
4170 /* Check if we already have channel with that dcid */
4171 if (__l2cap_get_chan_by_dcid(conn, scid)) {
4172 result = L2CAP_CR_SCID_IN_USE;
4173 goto response;
4174 }
4175
4176 chan = pchan->ops->new_connection(pchan);
4177 if (!chan)
4178 goto response;
4179
4180 /* For certain devices (ex: HID mouse), support for authentication,
4181 * pairing and bonding is optional. For such devices, inorder to avoid
4182 * the ACL alive for too long after L2CAP disconnection, reset the ACL
4183 * disc_timeout back to HCI_DISCONN_TIMEOUT during L2CAP connect.
4184 */
4185 conn->hcon->disc_timeout = HCI_DISCONN_TIMEOUT;
4186
4187 bacpy(&chan->src, &conn->hcon->src);
4188 bacpy(&chan->dst, &conn->hcon->dst);
4189 chan->src_type = bdaddr_src_type(conn->hcon);
4190 chan->dst_type = bdaddr_dst_type(conn->hcon);
4191 chan->psm = psm;
4192 chan->dcid = scid;
4193 chan->local_amp_id = amp_id;
4194
4195 __l2cap_chan_add(conn, chan);
4196
4197 dcid = chan->scid;
4198
4199 __set_chan_timer(chan, chan->ops->get_sndtimeo(chan));
4200
4201 chan->ident = cmd->ident;
4202
4203 if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE) {
4204 if (l2cap_chan_check_security(chan, false)) {
4205 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) {
4206 l2cap_state_change(chan, BT_CONNECT2);
4207 result = L2CAP_CR_PEND;
4208 status = L2CAP_CS_AUTHOR_PEND;
4209 chan->ops->defer(chan);
4210 } else {
4211 /* Force pending result for AMP controllers.
4212 * The connection will succeed after the
4213 * physical link is up.
4214 */
4215 if (amp_id == AMP_ID_BREDR) {
4216 l2cap_state_change(chan, BT_CONFIG);
4217 result = L2CAP_CR_SUCCESS;
4218 } else {
4219 l2cap_state_change(chan, BT_CONNECT2);
4220 result = L2CAP_CR_PEND;
4221 }
4222 status = L2CAP_CS_NO_INFO;
4223 }
4224 } else {
4225 l2cap_state_change(chan, BT_CONNECT2);
4226 result = L2CAP_CR_PEND;
4227 status = L2CAP_CS_AUTHEN_PEND;
4228 }
4229 } else {
4230 l2cap_state_change(chan, BT_CONNECT2);
4231 result = L2CAP_CR_PEND;
4232 status = L2CAP_CS_NO_INFO;
4233 }
4234
4235response:
4236 l2cap_chan_unlock(pchan);
4237 mutex_unlock(&conn->chan_lock);
4238 l2cap_chan_put(pchan);
4239
4240sendresp:
4241 rsp.scid = cpu_to_le16(scid);
4242 rsp.dcid = cpu_to_le16(dcid);
4243 rsp.result = cpu_to_le16(result);
4244 rsp.status = cpu_to_le16(status);
4245 l2cap_send_cmd(conn, cmd->ident, rsp_code, sizeof(rsp), &rsp);
4246
4247 if (result == L2CAP_CR_PEND && status == L2CAP_CS_NO_INFO) {
4248 struct l2cap_info_req info;
4249 info.type = cpu_to_le16(L2CAP_IT_FEAT_MASK);
4250
4251 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_SENT;
4252 conn->info_ident = l2cap_get_ident(conn);
4253
4254 schedule_delayed_work(&conn->info_timer, L2CAP_INFO_TIMEOUT);
4255
4256 l2cap_send_cmd(conn, conn->info_ident, L2CAP_INFO_REQ,
4257 sizeof(info), &info);
4258 }
4259
4260 if (chan && !test_bit(CONF_REQ_SENT, &chan->conf_state) &&
4261 result == L2CAP_CR_SUCCESS) {
4262 u8 buf[128];
4263 set_bit(CONF_REQ_SENT, &chan->conf_state);
4264 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
4265 l2cap_build_conf_req(chan, buf, sizeof(buf)), buf);
4266 chan->num_conf_req++;
4267 }
4268
4269 return chan;
4270}
4271
4272static int l2cap_connect_req(struct l2cap_conn *conn,
4273 struct l2cap_cmd_hdr *cmd, u16 cmd_len, u8 *data)
4274{
4275 struct hci_dev *hdev = conn->hcon->hdev;
4276 struct hci_conn *hcon = conn->hcon;
4277
4278 if (cmd_len < sizeof(struct l2cap_conn_req))
4279 return -EPROTO;
4280
4281 hci_dev_lock(hdev);
4282 if (hci_dev_test_flag(hdev, HCI_MGMT) &&
4283 !test_and_set_bit(HCI_CONN_MGMT_CONNECTED, &hcon->flags))
4284 mgmt_device_connected(hdev, hcon, NULL, 0);
4285 hci_dev_unlock(hdev);
4286
4287 l2cap_connect(conn, cmd, data, L2CAP_CONN_RSP, 0);
4288 return 0;
4289}
4290
4291static int l2cap_connect_create_rsp(struct l2cap_conn *conn,
4292 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4293 u8 *data)
4294{
4295 struct l2cap_conn_rsp *rsp = (struct l2cap_conn_rsp *) data;
4296 u16 scid, dcid, result, status;
4297 struct l2cap_chan *chan;
4298 u8 req[128];
4299 int err;
4300
4301 if (cmd_len < sizeof(*rsp))
4302 return -EPROTO;
4303
4304 scid = __le16_to_cpu(rsp->scid);
4305 dcid = __le16_to_cpu(rsp->dcid);
4306 result = __le16_to_cpu(rsp->result);
4307 status = __le16_to_cpu(rsp->status);
4308
4309 if (result == L2CAP_CR_SUCCESS && (dcid < L2CAP_CID_DYN_START ||
4310 dcid > L2CAP_CID_DYN_END))
4311 return -EPROTO;
4312
4313 BT_DBG("dcid 0x%4.4x scid 0x%4.4x result 0x%2.2x status 0x%2.2x",
4314 dcid, scid, result, status);
4315
4316 mutex_lock(&conn->chan_lock);
4317
4318 if (scid) {
4319 chan = __l2cap_get_chan_by_scid(conn, scid);
4320 if (!chan) {
4321 err = -EBADSLT;
4322 goto unlock;
4323 }
4324 } else {
4325 chan = __l2cap_get_chan_by_ident(conn, cmd->ident);
4326 if (!chan) {
4327 err = -EBADSLT;
4328 goto unlock;
4329 }
4330 }
4331
4332 chan = l2cap_chan_hold_unless_zero(chan);
4333 if (!chan) {
4334 err = -EBADSLT;
4335 goto unlock;
4336 }
4337
4338 err = 0;
4339
4340 l2cap_chan_lock(chan);
4341
4342 switch (result) {
4343 case L2CAP_CR_SUCCESS:
4344 if (__l2cap_get_chan_by_dcid(conn, dcid)) {
4345 err = -EBADSLT;
4346 break;
4347 }
4348
4349 l2cap_state_change(chan, BT_CONFIG);
4350 chan->ident = 0;
4351 chan->dcid = dcid;
4352 clear_bit(CONF_CONNECT_PEND, &chan->conf_state);
4353
4354 if (test_and_set_bit(CONF_REQ_SENT, &chan->conf_state))
4355 break;
4356
4357 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
4358 l2cap_build_conf_req(chan, req, sizeof(req)), req);
4359 chan->num_conf_req++;
4360 break;
4361
4362 case L2CAP_CR_PEND:
4363 set_bit(CONF_CONNECT_PEND, &chan->conf_state);
4364 break;
4365
4366 default:
4367 l2cap_chan_del(chan, ECONNREFUSED);
4368 break;
4369 }
4370
4371 l2cap_chan_unlock(chan);
4372 l2cap_chan_put(chan);
4373
4374unlock:
4375 mutex_unlock(&conn->chan_lock);
4376
4377 return err;
4378}
4379
4380static inline void set_default_fcs(struct l2cap_chan *chan)
4381{
4382 /* FCS is enabled only in ERTM or streaming mode, if one or both
4383 * sides request it.
4384 */
4385 if (chan->mode != L2CAP_MODE_ERTM && chan->mode != L2CAP_MODE_STREAMING)
4386 chan->fcs = L2CAP_FCS_NONE;
4387 else if (!test_bit(CONF_RECV_NO_FCS, &chan->conf_state))
4388 chan->fcs = L2CAP_FCS_CRC16;
4389}
4390
4391static void l2cap_send_efs_conf_rsp(struct l2cap_chan *chan, void *data,
4392 u8 ident, u16 flags)
4393{
4394 struct l2cap_conn *conn = chan->conn;
4395
4396 BT_DBG("conn %p chan %p ident %d flags 0x%4.4x", conn, chan, ident,
4397 flags);
4398
4399 clear_bit(CONF_LOC_CONF_PEND, &chan->conf_state);
4400 set_bit(CONF_OUTPUT_DONE, &chan->conf_state);
4401
4402 l2cap_send_cmd(conn, ident, L2CAP_CONF_RSP,
4403 l2cap_build_conf_rsp(chan, data,
4404 L2CAP_CONF_SUCCESS, flags), data);
4405}
4406
4407static void cmd_reject_invalid_cid(struct l2cap_conn *conn, u8 ident,
4408 u16 scid, u16 dcid)
4409{
4410 struct l2cap_cmd_rej_cid rej;
4411
4412 rej.reason = cpu_to_le16(L2CAP_REJ_INVALID_CID);
4413 rej.scid = __cpu_to_le16(scid);
4414 rej.dcid = __cpu_to_le16(dcid);
4415
4416 l2cap_send_cmd(conn, ident, L2CAP_COMMAND_REJ, sizeof(rej), &rej);
4417}
4418
4419static inline int l2cap_config_req(struct l2cap_conn *conn,
4420 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4421 u8 *data)
4422{
4423 struct l2cap_conf_req *req = (struct l2cap_conf_req *) data;
4424 u16 dcid, flags;
4425 u8 rsp[64];
4426 struct l2cap_chan *chan;
4427 int len, err = 0;
4428
4429 if (cmd_len < sizeof(*req))
4430 return -EPROTO;
4431
4432 dcid = __le16_to_cpu(req->dcid);
4433 flags = __le16_to_cpu(req->flags);
4434
4435 BT_DBG("dcid 0x%4.4x flags 0x%2.2x", dcid, flags);
4436
4437 chan = l2cap_get_chan_by_scid(conn, dcid);
4438 if (!chan) {
4439 cmd_reject_invalid_cid(conn, cmd->ident, dcid, 0);
4440 return 0;
4441 }
4442
4443 if (chan->state != BT_CONFIG && chan->state != BT_CONNECT2 &&
4444 chan->state != BT_CONNECTED) {
4445 cmd_reject_invalid_cid(conn, cmd->ident, chan->scid,
4446 chan->dcid);
4447 goto unlock;
4448 }
4449
4450 /* Reject if config buffer is too small. */
4451 len = cmd_len - sizeof(*req);
4452 if (chan->conf_len + len > sizeof(chan->conf_req)) {
4453 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP,
4454 l2cap_build_conf_rsp(chan, rsp,
4455 L2CAP_CONF_REJECT, flags), rsp);
4456 goto unlock;
4457 }
4458
4459 /* Store config. */
4460 memcpy(chan->conf_req + chan->conf_len, req->data, len);
4461 chan->conf_len += len;
4462
4463 if (flags & L2CAP_CONF_FLAG_CONTINUATION) {
4464 /* Incomplete config. Send empty response. */
4465 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP,
4466 l2cap_build_conf_rsp(chan, rsp,
4467 L2CAP_CONF_SUCCESS, flags), rsp);
4468 goto unlock;
4469 }
4470
4471 /* Complete config. */
4472 len = l2cap_parse_conf_req(chan, rsp, sizeof(rsp));
4473 if (len < 0) {
4474 l2cap_send_disconn_req(chan, ECONNRESET);
4475 goto unlock;
4476 }
4477
4478 chan->ident = cmd->ident;
4479 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP, len, rsp);
4480 if (chan->num_conf_rsp < L2CAP_CONF_MAX_CONF_RSP)
4481 chan->num_conf_rsp++;
4482
4483 /* Reset config buffer. */
4484 chan->conf_len = 0;
4485
4486 if (!test_bit(CONF_OUTPUT_DONE, &chan->conf_state))
4487 goto unlock;
4488
4489 if (test_bit(CONF_INPUT_DONE, &chan->conf_state)) {
4490 set_default_fcs(chan);
4491
4492 if (chan->mode == L2CAP_MODE_ERTM ||
4493 chan->mode == L2CAP_MODE_STREAMING)
4494 err = l2cap_ertm_init(chan);
4495
4496 if (err < 0)
4497 l2cap_send_disconn_req(chan, -err);
4498 else
4499 l2cap_chan_ready(chan);
4500
4501 goto unlock;
4502 }
4503
4504 if (!test_and_set_bit(CONF_REQ_SENT, &chan->conf_state)) {
4505 u8 buf[64];
4506 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
4507 l2cap_build_conf_req(chan, buf, sizeof(buf)), buf);
4508 chan->num_conf_req++;
4509 }
4510
4511 /* Got Conf Rsp PENDING from remote side and assume we sent
4512 Conf Rsp PENDING in the code above */
4513 if (test_bit(CONF_REM_CONF_PEND, &chan->conf_state) &&
4514 test_bit(CONF_LOC_CONF_PEND, &chan->conf_state)) {
4515
4516 /* check compatibility */
4517
4518 /* Send rsp for BR/EDR channel */
4519 if (!chan->hs_hcon)
4520 l2cap_send_efs_conf_rsp(chan, rsp, cmd->ident, flags);
4521 else
4522 chan->ident = cmd->ident;
4523 }
4524
4525unlock:
4526 l2cap_chan_unlock(chan);
4527 l2cap_chan_put(chan);
4528 return err;
4529}
4530
4531static inline int l2cap_config_rsp(struct l2cap_conn *conn,
4532 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4533 u8 *data)
4534{
4535 struct l2cap_conf_rsp *rsp = (struct l2cap_conf_rsp *)data;
4536 u16 scid, flags, result;
4537 struct l2cap_chan *chan;
4538 int len = cmd_len - sizeof(*rsp);
4539 int err = 0;
4540
4541 if (cmd_len < sizeof(*rsp))
4542 return -EPROTO;
4543
4544 scid = __le16_to_cpu(rsp->scid);
4545 flags = __le16_to_cpu(rsp->flags);
4546 result = __le16_to_cpu(rsp->result);
4547
4548 BT_DBG("scid 0x%4.4x flags 0x%2.2x result 0x%2.2x len %d", scid, flags,
4549 result, len);
4550
4551 chan = l2cap_get_chan_by_scid(conn, scid);
4552 if (!chan)
4553 return 0;
4554
4555 switch (result) {
4556 case L2CAP_CONF_SUCCESS:
4557 l2cap_conf_rfc_get(chan, rsp->data, len);
4558 clear_bit(CONF_REM_CONF_PEND, &chan->conf_state);
4559 break;
4560
4561 case L2CAP_CONF_PENDING:
4562 set_bit(CONF_REM_CONF_PEND, &chan->conf_state);
4563
4564 if (test_bit(CONF_LOC_CONF_PEND, &chan->conf_state)) {
4565 char buf[64];
4566
4567 len = l2cap_parse_conf_rsp(chan, rsp->data, len,
4568 buf, sizeof(buf), &result);
4569 if (len < 0) {
4570 l2cap_send_disconn_req(chan, ECONNRESET);
4571 goto done;
4572 }
4573
4574 if (!chan->hs_hcon) {
4575 l2cap_send_efs_conf_rsp(chan, buf, cmd->ident,
4576 0);
4577 } else {
4578 if (l2cap_check_efs(chan)) {
4579 amp_create_logical_link(chan);
4580 chan->ident = cmd->ident;
4581 }
4582 }
4583 }
4584 goto done;
4585
4586 case L2CAP_CONF_UNKNOWN:
4587 case L2CAP_CONF_UNACCEPT:
4588 if (chan->num_conf_rsp <= L2CAP_CONF_MAX_CONF_RSP) {
4589 char req[64];
4590
4591 if (len > sizeof(req) - sizeof(struct l2cap_conf_req)) {
4592 l2cap_send_disconn_req(chan, ECONNRESET);
4593 goto done;
4594 }
4595
4596 /* throw out any old stored conf requests */
4597 result = L2CAP_CONF_SUCCESS;
4598 len = l2cap_parse_conf_rsp(chan, rsp->data, len,
4599 req, sizeof(req), &result);
4600 if (len < 0) {
4601 l2cap_send_disconn_req(chan, ECONNRESET);
4602 goto done;
4603 }
4604
4605 l2cap_send_cmd(conn, l2cap_get_ident(conn),
4606 L2CAP_CONF_REQ, len, req);
4607 chan->num_conf_req++;
4608 if (result != L2CAP_CONF_SUCCESS)
4609 goto done;
4610 break;
4611 }
4612 fallthrough;
4613
4614 default:
4615 l2cap_chan_set_err(chan, ECONNRESET);
4616
4617 __set_chan_timer(chan, L2CAP_DISC_REJ_TIMEOUT);
4618 l2cap_send_disconn_req(chan, ECONNRESET);
4619 goto done;
4620 }
4621
4622 if (flags & L2CAP_CONF_FLAG_CONTINUATION)
4623 goto done;
4624
4625 set_bit(CONF_INPUT_DONE, &chan->conf_state);
4626
4627 if (test_bit(CONF_OUTPUT_DONE, &chan->conf_state)) {
4628 set_default_fcs(chan);
4629
4630 if (chan->mode == L2CAP_MODE_ERTM ||
4631 chan->mode == L2CAP_MODE_STREAMING)
4632 err = l2cap_ertm_init(chan);
4633
4634 if (err < 0)
4635 l2cap_send_disconn_req(chan, -err);
4636 else
4637 l2cap_chan_ready(chan);
4638 }
4639
4640done:
4641 l2cap_chan_unlock(chan);
4642 l2cap_chan_put(chan);
4643 return err;
4644}
4645
4646static inline int l2cap_disconnect_req(struct l2cap_conn *conn,
4647 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4648 u8 *data)
4649{
4650 struct l2cap_disconn_req *req = (struct l2cap_disconn_req *) data;
4651 struct l2cap_disconn_rsp rsp;
4652 u16 dcid, scid;
4653 struct l2cap_chan *chan;
4654
4655 if (cmd_len != sizeof(*req))
4656 return -EPROTO;
4657
4658 scid = __le16_to_cpu(req->scid);
4659 dcid = __le16_to_cpu(req->dcid);
4660
4661 BT_DBG("scid 0x%4.4x dcid 0x%4.4x", scid, dcid);
4662
4663 chan = l2cap_get_chan_by_scid(conn, dcid);
4664 if (!chan) {
4665 cmd_reject_invalid_cid(conn, cmd->ident, dcid, scid);
4666 return 0;
4667 }
4668
4669 rsp.dcid = cpu_to_le16(chan->scid);
4670 rsp.scid = cpu_to_le16(chan->dcid);
4671 l2cap_send_cmd(conn, cmd->ident, L2CAP_DISCONN_RSP, sizeof(rsp), &rsp);
4672
4673 chan->ops->set_shutdown(chan);
4674
4675 l2cap_chan_unlock(chan);
4676 mutex_lock(&conn->chan_lock);
4677 l2cap_chan_lock(chan);
4678 l2cap_chan_del(chan, ECONNRESET);
4679 mutex_unlock(&conn->chan_lock);
4680
4681 chan->ops->close(chan);
4682
4683 l2cap_chan_unlock(chan);
4684 l2cap_chan_put(chan);
4685
4686 return 0;
4687}
4688
4689static inline int l2cap_disconnect_rsp(struct l2cap_conn *conn,
4690 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4691 u8 *data)
4692{
4693 struct l2cap_disconn_rsp *rsp = (struct l2cap_disconn_rsp *) data;
4694 u16 dcid, scid;
4695 struct l2cap_chan *chan;
4696
4697 if (cmd_len != sizeof(*rsp))
4698 return -EPROTO;
4699
4700 scid = __le16_to_cpu(rsp->scid);
4701 dcid = __le16_to_cpu(rsp->dcid);
4702
4703 BT_DBG("dcid 0x%4.4x scid 0x%4.4x", dcid, scid);
4704
4705 chan = l2cap_get_chan_by_scid(conn, scid);
4706 if (!chan) {
4707 return 0;
4708 }
4709
4710 if (chan->state != BT_DISCONN) {
4711 l2cap_chan_unlock(chan);
4712 l2cap_chan_put(chan);
4713 return 0;
4714 }
4715
4716 l2cap_chan_unlock(chan);
4717 mutex_lock(&conn->chan_lock);
4718 l2cap_chan_lock(chan);
4719 l2cap_chan_del(chan, 0);
4720 mutex_unlock(&conn->chan_lock);
4721
4722 chan->ops->close(chan);
4723
4724 l2cap_chan_unlock(chan);
4725 l2cap_chan_put(chan);
4726
4727 return 0;
4728}
4729
4730static inline int l2cap_information_req(struct l2cap_conn *conn,
4731 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4732 u8 *data)
4733{
4734 struct l2cap_info_req *req = (struct l2cap_info_req *) data;
4735 u16 type;
4736
4737 if (cmd_len != sizeof(*req))
4738 return -EPROTO;
4739
4740 type = __le16_to_cpu(req->type);
4741
4742 BT_DBG("type 0x%4.4x", type);
4743
4744 if (type == L2CAP_IT_FEAT_MASK) {
4745 u8 buf[8];
4746 u32 feat_mask = l2cap_feat_mask;
4747 struct l2cap_info_rsp *rsp = (struct l2cap_info_rsp *) buf;
4748 rsp->type = cpu_to_le16(L2CAP_IT_FEAT_MASK);
4749 rsp->result = cpu_to_le16(L2CAP_IR_SUCCESS);
4750 if (!disable_ertm)
4751 feat_mask |= L2CAP_FEAT_ERTM | L2CAP_FEAT_STREAMING
4752 | L2CAP_FEAT_FCS;
4753 if (conn->local_fixed_chan & L2CAP_FC_A2MP)
4754 feat_mask |= L2CAP_FEAT_EXT_FLOW
4755 | L2CAP_FEAT_EXT_WINDOW;
4756
4757 put_unaligned_le32(feat_mask, rsp->data);
4758 l2cap_send_cmd(conn, cmd->ident, L2CAP_INFO_RSP, sizeof(buf),
4759 buf);
4760 } else if (type == L2CAP_IT_FIXED_CHAN) {
4761 u8 buf[12];
4762 struct l2cap_info_rsp *rsp = (struct l2cap_info_rsp *) buf;
4763
4764 rsp->type = cpu_to_le16(L2CAP_IT_FIXED_CHAN);
4765 rsp->result = cpu_to_le16(L2CAP_IR_SUCCESS);
4766 rsp->data[0] = conn->local_fixed_chan;
4767 memset(rsp->data + 1, 0, 7);
4768 l2cap_send_cmd(conn, cmd->ident, L2CAP_INFO_RSP, sizeof(buf),
4769 buf);
4770 } else {
4771 struct l2cap_info_rsp rsp;
4772 rsp.type = cpu_to_le16(type);
4773 rsp.result = cpu_to_le16(L2CAP_IR_NOTSUPP);
4774 l2cap_send_cmd(conn, cmd->ident, L2CAP_INFO_RSP, sizeof(rsp),
4775 &rsp);
4776 }
4777
4778 return 0;
4779}
4780
4781static inline int l2cap_information_rsp(struct l2cap_conn *conn,
4782 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4783 u8 *data)
4784{
4785 struct l2cap_info_rsp *rsp = (struct l2cap_info_rsp *) data;
4786 u16 type, result;
4787
4788 if (cmd_len < sizeof(*rsp))
4789 return -EPROTO;
4790
4791 type = __le16_to_cpu(rsp->type);
4792 result = __le16_to_cpu(rsp->result);
4793
4794 BT_DBG("type 0x%4.4x result 0x%2.2x", type, result);
4795
4796 /* L2CAP Info req/rsp are unbound to channels, add extra checks */
4797 if (cmd->ident != conn->info_ident ||
4798 conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE)
4799 return 0;
4800
4801 cancel_delayed_work(&conn->info_timer);
4802
4803 if (result != L2CAP_IR_SUCCESS) {
4804 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
4805 conn->info_ident = 0;
4806
4807 l2cap_conn_start(conn);
4808
4809 return 0;
4810 }
4811
4812 switch (type) {
4813 case L2CAP_IT_FEAT_MASK:
4814 conn->feat_mask = get_unaligned_le32(rsp->data);
4815
4816 if (conn->feat_mask & L2CAP_FEAT_FIXED_CHAN) {
4817 struct l2cap_info_req req;
4818 req.type = cpu_to_le16(L2CAP_IT_FIXED_CHAN);
4819
4820 conn->info_ident = l2cap_get_ident(conn);
4821
4822 l2cap_send_cmd(conn, conn->info_ident,
4823 L2CAP_INFO_REQ, sizeof(req), &req);
4824 } else {
4825 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
4826 conn->info_ident = 0;
4827
4828 l2cap_conn_start(conn);
4829 }
4830 break;
4831
4832 case L2CAP_IT_FIXED_CHAN:
4833 conn->remote_fixed_chan = rsp->data[0];
4834 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
4835 conn->info_ident = 0;
4836
4837 l2cap_conn_start(conn);
4838 break;
4839 }
4840
4841 return 0;
4842}
4843
4844static int l2cap_create_channel_req(struct l2cap_conn *conn,
4845 struct l2cap_cmd_hdr *cmd,
4846 u16 cmd_len, void *data)
4847{
4848 struct l2cap_create_chan_req *req = data;
4849 struct l2cap_create_chan_rsp rsp;
4850 struct l2cap_chan *chan;
4851 struct hci_dev *hdev;
4852 u16 psm, scid;
4853
4854 if (cmd_len != sizeof(*req))
4855 return -EPROTO;
4856
4857 if (!(conn->local_fixed_chan & L2CAP_FC_A2MP))
4858 return -EINVAL;
4859
4860 psm = le16_to_cpu(req->psm);
4861 scid = le16_to_cpu(req->scid);
4862
4863 BT_DBG("psm 0x%2.2x, scid 0x%4.4x, amp_id %d", psm, scid, req->amp_id);
4864
4865 /* For controller id 0 make BR/EDR connection */
4866 if (req->amp_id == AMP_ID_BREDR) {
4867 l2cap_connect(conn, cmd, data, L2CAP_CREATE_CHAN_RSP,
4868 req->amp_id);
4869 return 0;
4870 }
4871
4872 /* Validate AMP controller id */
4873 hdev = hci_dev_get(req->amp_id);
4874 if (!hdev)
4875 goto error;
4876
4877 if (hdev->dev_type != HCI_AMP || !test_bit(HCI_UP, &hdev->flags)) {
4878 hci_dev_put(hdev);
4879 goto error;
4880 }
4881
4882 chan = l2cap_connect(conn, cmd, data, L2CAP_CREATE_CHAN_RSP,
4883 req->amp_id);
4884 if (chan) {
4885 struct amp_mgr *mgr = conn->hcon->amp_mgr;
4886 struct hci_conn *hs_hcon;
4887
4888 hs_hcon = hci_conn_hash_lookup_ba(hdev, AMP_LINK,
4889 &conn->hcon->dst);
4890 if (!hs_hcon) {
4891 hci_dev_put(hdev);
4892 cmd_reject_invalid_cid(conn, cmd->ident, chan->scid,
4893 chan->dcid);
4894 return 0;
4895 }
4896
4897 BT_DBG("mgr %p bredr_chan %p hs_hcon %p", mgr, chan, hs_hcon);
4898
4899 mgr->bredr_chan = chan;
4900 chan->hs_hcon = hs_hcon;
4901 chan->fcs = L2CAP_FCS_NONE;
4902 conn->mtu = hdev->block_mtu;
4903 }
4904
4905 hci_dev_put(hdev);
4906
4907 return 0;
4908
4909error:
4910 rsp.dcid = 0;
4911 rsp.scid = cpu_to_le16(scid);
4912 rsp.result = cpu_to_le16(L2CAP_CR_BAD_AMP);
4913 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
4914
4915 l2cap_send_cmd(conn, cmd->ident, L2CAP_CREATE_CHAN_RSP,
4916 sizeof(rsp), &rsp);
4917
4918 return 0;
4919}
4920
4921static void l2cap_send_move_chan_req(struct l2cap_chan *chan, u8 dest_amp_id)
4922{
4923 struct l2cap_move_chan_req req;
4924 u8 ident;
4925
4926 BT_DBG("chan %p, dest_amp_id %d", chan, dest_amp_id);
4927
4928 ident = l2cap_get_ident(chan->conn);
4929 chan->ident = ident;
4930
4931 req.icid = cpu_to_le16(chan->scid);
4932 req.dest_amp_id = dest_amp_id;
4933
4934 l2cap_send_cmd(chan->conn, ident, L2CAP_MOVE_CHAN_REQ, sizeof(req),
4935 &req);
4936
4937 __set_chan_timer(chan, L2CAP_MOVE_TIMEOUT);
4938}
4939
4940static void l2cap_send_move_chan_rsp(struct l2cap_chan *chan, u16 result)
4941{
4942 struct l2cap_move_chan_rsp rsp;
4943
4944 BT_DBG("chan %p, result 0x%4.4x", chan, result);
4945
4946 rsp.icid = cpu_to_le16(chan->dcid);
4947 rsp.result = cpu_to_le16(result);
4948
4949 l2cap_send_cmd(chan->conn, chan->ident, L2CAP_MOVE_CHAN_RSP,
4950 sizeof(rsp), &rsp);
4951}
4952
4953static void l2cap_send_move_chan_cfm(struct l2cap_chan *chan, u16 result)
4954{
4955 struct l2cap_move_chan_cfm cfm;
4956
4957 BT_DBG("chan %p, result 0x%4.4x", chan, result);
4958
4959 chan->ident = l2cap_get_ident(chan->conn);
4960
4961 cfm.icid = cpu_to_le16(chan->scid);
4962 cfm.result = cpu_to_le16(result);
4963
4964 l2cap_send_cmd(chan->conn, chan->ident, L2CAP_MOVE_CHAN_CFM,
4965 sizeof(cfm), &cfm);
4966
4967 __set_chan_timer(chan, L2CAP_MOVE_TIMEOUT);
4968}
4969
4970static void l2cap_send_move_chan_cfm_icid(struct l2cap_conn *conn, u16 icid)
4971{
4972 struct l2cap_move_chan_cfm cfm;
4973
4974 BT_DBG("conn %p, icid 0x%4.4x", conn, icid);
4975
4976 cfm.icid = cpu_to_le16(icid);
4977 cfm.result = cpu_to_le16(L2CAP_MC_UNCONFIRMED);
4978
4979 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_MOVE_CHAN_CFM,
4980 sizeof(cfm), &cfm);
4981}
4982
4983static void l2cap_send_move_chan_cfm_rsp(struct l2cap_conn *conn, u8 ident,
4984 u16 icid)
4985{
4986 struct l2cap_move_chan_cfm_rsp rsp;
4987
4988 BT_DBG("icid 0x%4.4x", icid);
4989
4990 rsp.icid = cpu_to_le16(icid);
4991 l2cap_send_cmd(conn, ident, L2CAP_MOVE_CHAN_CFM_RSP, sizeof(rsp), &rsp);
4992}
4993
4994static void __release_logical_link(struct l2cap_chan *chan)
4995{
4996 chan->hs_hchan = NULL;
4997 chan->hs_hcon = NULL;
4998
4999 /* Placeholder - release the logical link */
5000}
5001
5002static void l2cap_logical_fail(struct l2cap_chan *chan)
5003{
5004 /* Logical link setup failed */
5005 if (chan->state != BT_CONNECTED) {
5006 /* Create channel failure, disconnect */
5007 l2cap_send_disconn_req(chan, ECONNRESET);
5008 return;
5009 }
5010
5011 switch (chan->move_role) {
5012 case L2CAP_MOVE_ROLE_RESPONDER:
5013 l2cap_move_done(chan);
5014 l2cap_send_move_chan_rsp(chan, L2CAP_MR_NOT_SUPP);
5015 break;
5016 case L2CAP_MOVE_ROLE_INITIATOR:
5017 if (chan->move_state == L2CAP_MOVE_WAIT_LOGICAL_COMP ||
5018 chan->move_state == L2CAP_MOVE_WAIT_LOGICAL_CFM) {
5019 /* Remote has only sent pending or
5020 * success responses, clean up
5021 */
5022 l2cap_move_done(chan);
5023 }
5024
5025 /* Other amp move states imply that the move
5026 * has already aborted
5027 */
5028 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
5029 break;
5030 }
5031}
5032
5033static void l2cap_logical_finish_create(struct l2cap_chan *chan,
5034 struct hci_chan *hchan)
5035{
5036 struct l2cap_conf_rsp rsp;
5037
5038 chan->hs_hchan = hchan;
5039 chan->hs_hcon->l2cap_data = chan->conn;
5040
5041 l2cap_send_efs_conf_rsp(chan, &rsp, chan->ident, 0);
5042
5043 if (test_bit(CONF_INPUT_DONE, &chan->conf_state)) {
5044 int err;
5045
5046 set_default_fcs(chan);
5047
5048 err = l2cap_ertm_init(chan);
5049 if (err < 0)
5050 l2cap_send_disconn_req(chan, -err);
5051 else
5052 l2cap_chan_ready(chan);
5053 }
5054}
5055
5056static void l2cap_logical_finish_move(struct l2cap_chan *chan,
5057 struct hci_chan *hchan)
5058{
5059 chan->hs_hcon = hchan->conn;
5060 chan->hs_hcon->l2cap_data = chan->conn;
5061
5062 BT_DBG("move_state %d", chan->move_state);
5063
5064 switch (chan->move_state) {
5065 case L2CAP_MOVE_WAIT_LOGICAL_COMP:
5066 /* Move confirm will be sent after a success
5067 * response is received
5068 */
5069 chan->move_state = L2CAP_MOVE_WAIT_RSP_SUCCESS;
5070 break;
5071 case L2CAP_MOVE_WAIT_LOGICAL_CFM:
5072 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
5073 chan->move_state = L2CAP_MOVE_WAIT_LOCAL_BUSY;
5074 } else if (chan->move_role == L2CAP_MOVE_ROLE_INITIATOR) {
5075 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM_RSP;
5076 l2cap_send_move_chan_cfm(chan, L2CAP_MC_CONFIRMED);
5077 } else if (chan->move_role == L2CAP_MOVE_ROLE_RESPONDER) {
5078 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM;
5079 l2cap_send_move_chan_rsp(chan, L2CAP_MR_SUCCESS);
5080 }
5081 break;
5082 default:
5083 /* Move was not in expected state, free the channel */
5084 __release_logical_link(chan);
5085
5086 chan->move_state = L2CAP_MOVE_STABLE;
5087 }
5088}
5089
5090/* Call with chan locked */
5091void l2cap_logical_cfm(struct l2cap_chan *chan, struct hci_chan *hchan,
5092 u8 status)
5093{
5094 BT_DBG("chan %p, hchan %p, status %d", chan, hchan, status);
5095
5096 if (status) {
5097 l2cap_logical_fail(chan);
5098 __release_logical_link(chan);
5099 return;
5100 }
5101
5102 if (chan->state != BT_CONNECTED) {
5103 /* Ignore logical link if channel is on BR/EDR */
5104 if (chan->local_amp_id != AMP_ID_BREDR)
5105 l2cap_logical_finish_create(chan, hchan);
5106 } else {
5107 l2cap_logical_finish_move(chan, hchan);
5108 }
5109}
5110
5111void l2cap_move_start(struct l2cap_chan *chan)
5112{
5113 BT_DBG("chan %p", chan);
5114
5115 if (chan->local_amp_id == AMP_ID_BREDR) {
5116 if (chan->chan_policy != BT_CHANNEL_POLICY_AMP_PREFERRED)
5117 return;
5118 chan->move_role = L2CAP_MOVE_ROLE_INITIATOR;
5119 chan->move_state = L2CAP_MOVE_WAIT_PREPARE;
5120 /* Placeholder - start physical link setup */
5121 } else {
5122 chan->move_role = L2CAP_MOVE_ROLE_INITIATOR;
5123 chan->move_state = L2CAP_MOVE_WAIT_RSP_SUCCESS;
5124 chan->move_id = 0;
5125 l2cap_move_setup(chan);
5126 l2cap_send_move_chan_req(chan, 0);
5127 }
5128}
5129
5130static void l2cap_do_create(struct l2cap_chan *chan, int result,
5131 u8 local_amp_id, u8 remote_amp_id)
5132{
5133 BT_DBG("chan %p state %s %u -> %u", chan, state_to_string(chan->state),
5134 local_amp_id, remote_amp_id);
5135
5136 chan->fcs = L2CAP_FCS_NONE;
5137
5138 /* Outgoing channel on AMP */
5139 if (chan->state == BT_CONNECT) {
5140 if (result == L2CAP_CR_SUCCESS) {
5141 chan->local_amp_id = local_amp_id;
5142 l2cap_send_create_chan_req(chan, remote_amp_id);
5143 } else {
5144 /* Revert to BR/EDR connect */
5145 l2cap_send_conn_req(chan);
5146 }
5147
5148 return;
5149 }
5150
5151 /* Incoming channel on AMP */
5152 if (__l2cap_no_conn_pending(chan)) {
5153 struct l2cap_conn_rsp rsp;
5154 char buf[128];
5155 rsp.scid = cpu_to_le16(chan->dcid);
5156 rsp.dcid = cpu_to_le16(chan->scid);
5157
5158 if (result == L2CAP_CR_SUCCESS) {
5159 /* Send successful response */
5160 rsp.result = cpu_to_le16(L2CAP_CR_SUCCESS);
5161 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
5162 } else {
5163 /* Send negative response */
5164 rsp.result = cpu_to_le16(L2CAP_CR_NO_MEM);
5165 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
5166 }
5167
5168 l2cap_send_cmd(chan->conn, chan->ident, L2CAP_CREATE_CHAN_RSP,
5169 sizeof(rsp), &rsp);
5170
5171 if (result == L2CAP_CR_SUCCESS) {
5172 l2cap_state_change(chan, BT_CONFIG);
5173 set_bit(CONF_REQ_SENT, &chan->conf_state);
5174 l2cap_send_cmd(chan->conn, l2cap_get_ident(chan->conn),
5175 L2CAP_CONF_REQ,
5176 l2cap_build_conf_req(chan, buf, sizeof(buf)), buf);
5177 chan->num_conf_req++;
5178 }
5179 }
5180}
5181
5182static void l2cap_do_move_initiate(struct l2cap_chan *chan, u8 local_amp_id,
5183 u8 remote_amp_id)
5184{
5185 l2cap_move_setup(chan);
5186 chan->move_id = local_amp_id;
5187 chan->move_state = L2CAP_MOVE_WAIT_RSP;
5188
5189 l2cap_send_move_chan_req(chan, remote_amp_id);
5190}
5191
5192static void l2cap_do_move_respond(struct l2cap_chan *chan, int result)
5193{
5194 struct hci_chan *hchan = NULL;
5195
5196 /* Placeholder - get hci_chan for logical link */
5197
5198 if (hchan) {
5199 if (hchan->state == BT_CONNECTED) {
5200 /* Logical link is ready to go */
5201 chan->hs_hcon = hchan->conn;
5202 chan->hs_hcon->l2cap_data = chan->conn;
5203 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM;
5204 l2cap_send_move_chan_rsp(chan, L2CAP_MR_SUCCESS);
5205
5206 l2cap_logical_cfm(chan, hchan, L2CAP_MR_SUCCESS);
5207 } else {
5208 /* Wait for logical link to be ready */
5209 chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_CFM;
5210 }
5211 } else {
5212 /* Logical link not available */
5213 l2cap_send_move_chan_rsp(chan, L2CAP_MR_NOT_ALLOWED);
5214 }
5215}
5216
5217static void l2cap_do_move_cancel(struct l2cap_chan *chan, int result)
5218{
5219 if (chan->move_role == L2CAP_MOVE_ROLE_RESPONDER) {
5220 u8 rsp_result;
5221 if (result == -EINVAL)
5222 rsp_result = L2CAP_MR_BAD_ID;
5223 else
5224 rsp_result = L2CAP_MR_NOT_ALLOWED;
5225
5226 l2cap_send_move_chan_rsp(chan, rsp_result);
5227 }
5228
5229 chan->move_role = L2CAP_MOVE_ROLE_NONE;
5230 chan->move_state = L2CAP_MOVE_STABLE;
5231
5232 /* Restart data transmission */
5233 l2cap_ertm_send(chan);
5234}
5235
5236/* Invoke with locked chan */
5237void __l2cap_physical_cfm(struct l2cap_chan *chan, int result)
5238{
5239 u8 local_amp_id = chan->local_amp_id;
5240 u8 remote_amp_id = chan->remote_amp_id;
5241
5242 BT_DBG("chan %p, result %d, local_amp_id %d, remote_amp_id %d",
5243 chan, result, local_amp_id, remote_amp_id);
5244
5245 if (chan->state == BT_DISCONN || chan->state == BT_CLOSED)
5246 return;
5247
5248 if (chan->state != BT_CONNECTED) {
5249 l2cap_do_create(chan, result, local_amp_id, remote_amp_id);
5250 } else if (result != L2CAP_MR_SUCCESS) {
5251 l2cap_do_move_cancel(chan, result);
5252 } else {
5253 switch (chan->move_role) {
5254 case L2CAP_MOVE_ROLE_INITIATOR:
5255 l2cap_do_move_initiate(chan, local_amp_id,
5256 remote_amp_id);
5257 break;
5258 case L2CAP_MOVE_ROLE_RESPONDER:
5259 l2cap_do_move_respond(chan, result);
5260 break;
5261 default:
5262 l2cap_do_move_cancel(chan, result);
5263 break;
5264 }
5265 }
5266}
5267
5268static inline int l2cap_move_channel_req(struct l2cap_conn *conn,
5269 struct l2cap_cmd_hdr *cmd,
5270 u16 cmd_len, void *data)
5271{
5272 struct l2cap_move_chan_req *req = data;
5273 struct l2cap_move_chan_rsp rsp;
5274 struct l2cap_chan *chan;
5275 u16 icid = 0;
5276 u16 result = L2CAP_MR_NOT_ALLOWED;
5277
5278 if (cmd_len != sizeof(*req))
5279 return -EPROTO;
5280
5281 icid = le16_to_cpu(req->icid);
5282
5283 BT_DBG("icid 0x%4.4x, dest_amp_id %d", icid, req->dest_amp_id);
5284
5285 if (!(conn->local_fixed_chan & L2CAP_FC_A2MP))
5286 return -EINVAL;
5287
5288 chan = l2cap_get_chan_by_dcid(conn, icid);
5289 if (!chan) {
5290 rsp.icid = cpu_to_le16(icid);
5291 rsp.result = cpu_to_le16(L2CAP_MR_NOT_ALLOWED);
5292 l2cap_send_cmd(conn, cmd->ident, L2CAP_MOVE_CHAN_RSP,
5293 sizeof(rsp), &rsp);
5294 return 0;
5295 }
5296
5297 chan->ident = cmd->ident;
5298
5299 if (chan->scid < L2CAP_CID_DYN_START ||
5300 chan->chan_policy == BT_CHANNEL_POLICY_BREDR_ONLY ||
5301 (chan->mode != L2CAP_MODE_ERTM &&
5302 chan->mode != L2CAP_MODE_STREAMING)) {
5303 result = L2CAP_MR_NOT_ALLOWED;
5304 goto send_move_response;
5305 }
5306
5307 if (chan->local_amp_id == req->dest_amp_id) {
5308 result = L2CAP_MR_SAME_ID;
5309 goto send_move_response;
5310 }
5311
5312 if (req->dest_amp_id != AMP_ID_BREDR) {
5313 struct hci_dev *hdev;
5314 hdev = hci_dev_get(req->dest_amp_id);
5315 if (!hdev || hdev->dev_type != HCI_AMP ||
5316 !test_bit(HCI_UP, &hdev->flags)) {
5317 if (hdev)
5318 hci_dev_put(hdev);
5319
5320 result = L2CAP_MR_BAD_ID;
5321 goto send_move_response;
5322 }
5323 hci_dev_put(hdev);
5324 }
5325
5326 /* Detect a move collision. Only send a collision response
5327 * if this side has "lost", otherwise proceed with the move.
5328 * The winner has the larger bd_addr.
5329 */
5330 if ((__chan_is_moving(chan) ||
5331 chan->move_role != L2CAP_MOVE_ROLE_NONE) &&
5332 bacmp(&conn->hcon->src, &conn->hcon->dst) > 0) {
5333 result = L2CAP_MR_COLLISION;
5334 goto send_move_response;
5335 }
5336
5337 chan->move_role = L2CAP_MOVE_ROLE_RESPONDER;
5338 l2cap_move_setup(chan);
5339 chan->move_id = req->dest_amp_id;
5340
5341 if (req->dest_amp_id == AMP_ID_BREDR) {
5342 /* Moving to BR/EDR */
5343 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
5344 chan->move_state = L2CAP_MOVE_WAIT_LOCAL_BUSY;
5345 result = L2CAP_MR_PEND;
5346 } else {
5347 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM;
5348 result = L2CAP_MR_SUCCESS;
5349 }
5350 } else {
5351 chan->move_state = L2CAP_MOVE_WAIT_PREPARE;
5352 /* Placeholder - uncomment when amp functions are available */
5353 /*amp_accept_physical(chan, req->dest_amp_id);*/
5354 result = L2CAP_MR_PEND;
5355 }
5356
5357send_move_response:
5358 l2cap_send_move_chan_rsp(chan, result);
5359
5360 l2cap_chan_unlock(chan);
5361 l2cap_chan_put(chan);
5362
5363 return 0;
5364}
5365
5366static void l2cap_move_continue(struct l2cap_conn *conn, u16 icid, u16 result)
5367{
5368 struct l2cap_chan *chan;
5369 struct hci_chan *hchan = NULL;
5370
5371 chan = l2cap_get_chan_by_scid(conn, icid);
5372 if (!chan) {
5373 l2cap_send_move_chan_cfm_icid(conn, icid);
5374 return;
5375 }
5376
5377 __clear_chan_timer(chan);
5378 if (result == L2CAP_MR_PEND)
5379 __set_chan_timer(chan, L2CAP_MOVE_ERTX_TIMEOUT);
5380
5381 switch (chan->move_state) {
5382 case L2CAP_MOVE_WAIT_LOGICAL_COMP:
5383 /* Move confirm will be sent when logical link
5384 * is complete.
5385 */
5386 chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_CFM;
5387 break;
5388 case L2CAP_MOVE_WAIT_RSP_SUCCESS:
5389 if (result == L2CAP_MR_PEND) {
5390 break;
5391 } else if (test_bit(CONN_LOCAL_BUSY,
5392 &chan->conn_state)) {
5393 chan->move_state = L2CAP_MOVE_WAIT_LOCAL_BUSY;
5394 } else {
5395 /* Logical link is up or moving to BR/EDR,
5396 * proceed with move
5397 */
5398 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM_RSP;
5399 l2cap_send_move_chan_cfm(chan, L2CAP_MC_CONFIRMED);
5400 }
5401 break;
5402 case L2CAP_MOVE_WAIT_RSP:
5403 /* Moving to AMP */
5404 if (result == L2CAP_MR_SUCCESS) {
5405 /* Remote is ready, send confirm immediately
5406 * after logical link is ready
5407 */
5408 chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_CFM;
5409 } else {
5410 /* Both logical link and move success
5411 * are required to confirm
5412 */
5413 chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_COMP;
5414 }
5415
5416 /* Placeholder - get hci_chan for logical link */
5417 if (!hchan) {
5418 /* Logical link not available */
5419 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
5420 break;
5421 }
5422
5423 /* If the logical link is not yet connected, do not
5424 * send confirmation.
5425 */
5426 if (hchan->state != BT_CONNECTED)
5427 break;
5428
5429 /* Logical link is already ready to go */
5430
5431 chan->hs_hcon = hchan->conn;
5432 chan->hs_hcon->l2cap_data = chan->conn;
5433
5434 if (result == L2CAP_MR_SUCCESS) {
5435 /* Can confirm now */
5436 l2cap_send_move_chan_cfm(chan, L2CAP_MC_CONFIRMED);
5437 } else {
5438 /* Now only need move success
5439 * to confirm
5440 */
5441 chan->move_state = L2CAP_MOVE_WAIT_RSP_SUCCESS;
5442 }
5443
5444 l2cap_logical_cfm(chan, hchan, L2CAP_MR_SUCCESS);
5445 break;
5446 default:
5447 /* Any other amp move state means the move failed. */
5448 chan->move_id = chan->local_amp_id;
5449 l2cap_move_done(chan);
5450 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
5451 }
5452
5453 l2cap_chan_unlock(chan);
5454 l2cap_chan_put(chan);
5455}
5456
5457static void l2cap_move_fail(struct l2cap_conn *conn, u8 ident, u16 icid,
5458 u16 result)
5459{
5460 struct l2cap_chan *chan;
5461
5462 chan = l2cap_get_chan_by_ident(conn, ident);
5463 if (!chan) {
5464 /* Could not locate channel, icid is best guess */
5465 l2cap_send_move_chan_cfm_icid(conn, icid);
5466 return;
5467 }
5468
5469 __clear_chan_timer(chan);
5470
5471 if (chan->move_role == L2CAP_MOVE_ROLE_INITIATOR) {
5472 if (result == L2CAP_MR_COLLISION) {
5473 chan->move_role = L2CAP_MOVE_ROLE_RESPONDER;
5474 } else {
5475 /* Cleanup - cancel move */
5476 chan->move_id = chan->local_amp_id;
5477 l2cap_move_done(chan);
5478 }
5479 }
5480
5481 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
5482
5483 l2cap_chan_unlock(chan);
5484 l2cap_chan_put(chan);
5485}
5486
5487static int l2cap_move_channel_rsp(struct l2cap_conn *conn,
5488 struct l2cap_cmd_hdr *cmd,
5489 u16 cmd_len, void *data)
5490{
5491 struct l2cap_move_chan_rsp *rsp = data;
5492 u16 icid, result;
5493
5494 if (cmd_len != sizeof(*rsp))
5495 return -EPROTO;
5496
5497 icid = le16_to_cpu(rsp->icid);
5498 result = le16_to_cpu(rsp->result);
5499
5500 BT_DBG("icid 0x%4.4x, result 0x%4.4x", icid, result);
5501
5502 if (result == L2CAP_MR_SUCCESS || result == L2CAP_MR_PEND)
5503 l2cap_move_continue(conn, icid, result);
5504 else
5505 l2cap_move_fail(conn, cmd->ident, icid, result);
5506
5507 return 0;
5508}
5509
5510static int l2cap_move_channel_confirm(struct l2cap_conn *conn,
5511 struct l2cap_cmd_hdr *cmd,
5512 u16 cmd_len, void *data)
5513{
5514 struct l2cap_move_chan_cfm *cfm = data;
5515 struct l2cap_chan *chan;
5516 u16 icid, result;
5517
5518 if (cmd_len != sizeof(*cfm))
5519 return -EPROTO;
5520
5521 icid = le16_to_cpu(cfm->icid);
5522 result = le16_to_cpu(cfm->result);
5523
5524 BT_DBG("icid 0x%4.4x, result 0x%4.4x", icid, result);
5525
5526 chan = l2cap_get_chan_by_dcid(conn, icid);
5527 if (!chan) {
5528 /* Spec requires a response even if the icid was not found */
5529 l2cap_send_move_chan_cfm_rsp(conn, cmd->ident, icid);
5530 return 0;
5531 }
5532
5533 if (chan->move_state == L2CAP_MOVE_WAIT_CONFIRM) {
5534 if (result == L2CAP_MC_CONFIRMED) {
5535 chan->local_amp_id = chan->move_id;
5536 if (chan->local_amp_id == AMP_ID_BREDR)
5537 __release_logical_link(chan);
5538 } else {
5539 chan->move_id = chan->local_amp_id;
5540 }
5541
5542 l2cap_move_done(chan);
5543 }
5544
5545 l2cap_send_move_chan_cfm_rsp(conn, cmd->ident, icid);
5546
5547 l2cap_chan_unlock(chan);
5548 l2cap_chan_put(chan);
5549
5550 return 0;
5551}
5552
5553static inline int l2cap_move_channel_confirm_rsp(struct l2cap_conn *conn,
5554 struct l2cap_cmd_hdr *cmd,
5555 u16 cmd_len, void *data)
5556{
5557 struct l2cap_move_chan_cfm_rsp *rsp = data;
5558 struct l2cap_chan *chan;
5559 u16 icid;
5560
5561 if (cmd_len != sizeof(*rsp))
5562 return -EPROTO;
5563
5564 icid = le16_to_cpu(rsp->icid);
5565
5566 BT_DBG("icid 0x%4.4x", icid);
5567
5568 chan = l2cap_get_chan_by_scid(conn, icid);
5569 if (!chan)
5570 return 0;
5571
5572 __clear_chan_timer(chan);
5573
5574 if (chan->move_state == L2CAP_MOVE_WAIT_CONFIRM_RSP) {
5575 chan->local_amp_id = chan->move_id;
5576
5577 if (chan->local_amp_id == AMP_ID_BREDR && chan->hs_hchan)
5578 __release_logical_link(chan);
5579
5580 l2cap_move_done(chan);
5581 }
5582
5583 l2cap_chan_unlock(chan);
5584 l2cap_chan_put(chan);
5585
5586 return 0;
5587}
5588
5589static inline int l2cap_conn_param_update_req(struct l2cap_conn *conn,
5590 struct l2cap_cmd_hdr *cmd,
5591 u16 cmd_len, u8 *data)
5592{
5593 struct hci_conn *hcon = conn->hcon;
5594 struct l2cap_conn_param_update_req *req;
5595 struct l2cap_conn_param_update_rsp rsp;
5596 u16 min, max, latency, to_multiplier;
5597 int err;
5598
5599 if (hcon->role != HCI_ROLE_MASTER)
5600 return -EINVAL;
5601
5602 if (cmd_len != sizeof(struct l2cap_conn_param_update_req))
5603 return -EPROTO;
5604
5605 req = (struct l2cap_conn_param_update_req *) data;
5606 min = __le16_to_cpu(req->min);
5607 max = __le16_to_cpu(req->max);
5608 latency = __le16_to_cpu(req->latency);
5609 to_multiplier = __le16_to_cpu(req->to_multiplier);
5610
5611 BT_DBG("min 0x%4.4x max 0x%4.4x latency: 0x%4.4x Timeout: 0x%4.4x",
5612 min, max, latency, to_multiplier);
5613
5614 memset(&rsp, 0, sizeof(rsp));
5615
5616 if (max > hcon->le_conn_max_interval) {
5617 BT_DBG("requested connection interval exceeds current bounds.");
5618 err = -EINVAL;
5619 } else {
5620 err = hci_check_conn_params(min, max, latency, to_multiplier);
5621 }
5622
5623 if (err)
5624 rsp.result = cpu_to_le16(L2CAP_CONN_PARAM_REJECTED);
5625 else
5626 rsp.result = cpu_to_le16(L2CAP_CONN_PARAM_ACCEPTED);
5627
5628 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONN_PARAM_UPDATE_RSP,
5629 sizeof(rsp), &rsp);
5630
5631 if (!err) {
5632 u8 store_hint;
5633
5634 store_hint = hci_le_conn_update(hcon, min, max, latency,
5635 to_multiplier);
5636 mgmt_new_conn_param(hcon->hdev, &hcon->dst, hcon->dst_type,
5637 store_hint, min, max, latency,
5638 to_multiplier);
5639
5640 }
5641
5642 return 0;
5643}
5644
5645static int l2cap_le_connect_rsp(struct l2cap_conn *conn,
5646 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5647 u8 *data)
5648{
5649 struct l2cap_le_conn_rsp *rsp = (struct l2cap_le_conn_rsp *) data;
5650 struct hci_conn *hcon = conn->hcon;
5651 u16 dcid, mtu, mps, credits, result;
5652 struct l2cap_chan *chan;
5653 int err, sec_level;
5654
5655 if (cmd_len < sizeof(*rsp))
5656 return -EPROTO;
5657
5658 dcid = __le16_to_cpu(rsp->dcid);
5659 mtu = __le16_to_cpu(rsp->mtu);
5660 mps = __le16_to_cpu(rsp->mps);
5661 credits = __le16_to_cpu(rsp->credits);
5662 result = __le16_to_cpu(rsp->result);
5663
5664 if (result == L2CAP_CR_LE_SUCCESS && (mtu < 23 || mps < 23 ||
5665 dcid < L2CAP_CID_DYN_START ||
5666 dcid > L2CAP_CID_LE_DYN_END))
5667 return -EPROTO;
5668
5669 BT_DBG("dcid 0x%4.4x mtu %u mps %u credits %u result 0x%2.2x",
5670 dcid, mtu, mps, credits, result);
5671
5672 mutex_lock(&conn->chan_lock);
5673
5674 chan = __l2cap_get_chan_by_ident(conn, cmd->ident);
5675 if (!chan) {
5676 err = -EBADSLT;
5677 goto unlock;
5678 }
5679
5680 err = 0;
5681
5682 l2cap_chan_lock(chan);
5683
5684 switch (result) {
5685 case L2CAP_CR_LE_SUCCESS:
5686 if (__l2cap_get_chan_by_dcid(conn, dcid)) {
5687 err = -EBADSLT;
5688 break;
5689 }
5690
5691 chan->ident = 0;
5692 chan->dcid = dcid;
5693 chan->omtu = mtu;
5694 chan->remote_mps = mps;
5695 chan->tx_credits = credits;
5696 l2cap_chan_ready(chan);
5697 break;
5698
5699 case L2CAP_CR_LE_AUTHENTICATION:
5700 case L2CAP_CR_LE_ENCRYPTION:
5701 /* If we already have MITM protection we can't do
5702 * anything.
5703 */
5704 if (hcon->sec_level > BT_SECURITY_MEDIUM) {
5705 l2cap_chan_del(chan, ECONNREFUSED);
5706 break;
5707 }
5708
5709 sec_level = hcon->sec_level + 1;
5710 if (chan->sec_level < sec_level)
5711 chan->sec_level = sec_level;
5712
5713 /* We'll need to send a new Connect Request */
5714 clear_bit(FLAG_LE_CONN_REQ_SENT, &chan->flags);
5715
5716 smp_conn_security(hcon, chan->sec_level);
5717 break;
5718
5719 default:
5720 l2cap_chan_del(chan, ECONNREFUSED);
5721 break;
5722 }
5723
5724 l2cap_chan_unlock(chan);
5725
5726unlock:
5727 mutex_unlock(&conn->chan_lock);
5728
5729 return err;
5730}
5731
5732static inline int l2cap_bredr_sig_cmd(struct l2cap_conn *conn,
5733 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5734 u8 *data)
5735{
5736 int err = 0;
5737
5738 switch (cmd->code) {
5739 case L2CAP_COMMAND_REJ:
5740 l2cap_command_rej(conn, cmd, cmd_len, data);
5741 break;
5742
5743 case L2CAP_CONN_REQ:
5744 err = l2cap_connect_req(conn, cmd, cmd_len, data);
5745 break;
5746
5747 case L2CAP_CONN_RSP:
5748 case L2CAP_CREATE_CHAN_RSP:
5749 l2cap_connect_create_rsp(conn, cmd, cmd_len, data);
5750 break;
5751
5752 case L2CAP_CONF_REQ:
5753 err = l2cap_config_req(conn, cmd, cmd_len, data);
5754 break;
5755
5756 case L2CAP_CONF_RSP:
5757 l2cap_config_rsp(conn, cmd, cmd_len, data);
5758 break;
5759
5760 case L2CAP_DISCONN_REQ:
5761 err = l2cap_disconnect_req(conn, cmd, cmd_len, data);
5762 break;
5763
5764 case L2CAP_DISCONN_RSP:
5765 l2cap_disconnect_rsp(conn, cmd, cmd_len, data);
5766 break;
5767
5768 case L2CAP_ECHO_REQ:
5769 l2cap_send_cmd(conn, cmd->ident, L2CAP_ECHO_RSP, cmd_len, data);
5770 break;
5771
5772 case L2CAP_ECHO_RSP:
5773 break;
5774
5775 case L2CAP_INFO_REQ:
5776 err = l2cap_information_req(conn, cmd, cmd_len, data);
5777 break;
5778
5779 case L2CAP_INFO_RSP:
5780 l2cap_information_rsp(conn, cmd, cmd_len, data);
5781 break;
5782
5783 case L2CAP_CREATE_CHAN_REQ:
5784 err = l2cap_create_channel_req(conn, cmd, cmd_len, data);
5785 break;
5786
5787 case L2CAP_MOVE_CHAN_REQ:
5788 err = l2cap_move_channel_req(conn, cmd, cmd_len, data);
5789 break;
5790
5791 case L2CAP_MOVE_CHAN_RSP:
5792 l2cap_move_channel_rsp(conn, cmd, cmd_len, data);
5793 break;
5794
5795 case L2CAP_MOVE_CHAN_CFM:
5796 err = l2cap_move_channel_confirm(conn, cmd, cmd_len, data);
5797 break;
5798
5799 case L2CAP_MOVE_CHAN_CFM_RSP:
5800 l2cap_move_channel_confirm_rsp(conn, cmd, cmd_len, data);
5801 break;
5802
5803 default:
5804 BT_ERR("Unknown BR/EDR signaling command 0x%2.2x", cmd->code);
5805 err = -EINVAL;
5806 break;
5807 }
5808
5809 return err;
5810}
5811
5812static int l2cap_le_connect_req(struct l2cap_conn *conn,
5813 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5814 u8 *data)
5815{
5816 struct l2cap_le_conn_req *req = (struct l2cap_le_conn_req *) data;
5817 struct l2cap_le_conn_rsp rsp;
5818 struct l2cap_chan *chan, *pchan;
5819 u16 dcid, scid, credits, mtu, mps;
5820 __le16 psm;
5821 u8 result;
5822
5823 if (cmd_len != sizeof(*req))
5824 return -EPROTO;
5825
5826 scid = __le16_to_cpu(req->scid);
5827 mtu = __le16_to_cpu(req->mtu);
5828 mps = __le16_to_cpu(req->mps);
5829 psm = req->psm;
5830 dcid = 0;
5831 credits = 0;
5832
5833 if (mtu < 23 || mps < 23)
5834 return -EPROTO;
5835
5836 BT_DBG("psm 0x%2.2x scid 0x%4.4x mtu %u mps %u", __le16_to_cpu(psm),
5837 scid, mtu, mps);
5838
5839 /* BLUETOOTH CORE SPECIFICATION Version 5.3 | Vol 3, Part A
5840 * page 1059:
5841 *
5842 * Valid range: 0x0001-0x00ff
5843 *
5844 * Table 4.15: L2CAP_LE_CREDIT_BASED_CONNECTION_REQ SPSM ranges
5845 */
5846 if (!psm || __le16_to_cpu(psm) > L2CAP_PSM_LE_DYN_END) {
5847 result = L2CAP_CR_LE_BAD_PSM;
5848 chan = NULL;
5849 goto response;
5850 }
5851
5852 /* Check if we have socket listening on psm */
5853 pchan = l2cap_global_chan_by_psm(BT_LISTEN, psm, &conn->hcon->src,
5854 &conn->hcon->dst, LE_LINK);
5855 if (!pchan) {
5856 result = L2CAP_CR_LE_BAD_PSM;
5857 chan = NULL;
5858 goto response;
5859 }
5860
5861 mutex_lock(&conn->chan_lock);
5862 l2cap_chan_lock(pchan);
5863
5864 if (!smp_sufficient_security(conn->hcon, pchan->sec_level,
5865 SMP_ALLOW_STK)) {
5866 result = L2CAP_CR_LE_AUTHENTICATION;
5867 chan = NULL;
5868 goto response_unlock;
5869 }
5870
5871 /* Check for valid dynamic CID range */
5872 if (scid < L2CAP_CID_DYN_START || scid > L2CAP_CID_LE_DYN_END) {
5873 result = L2CAP_CR_LE_INVALID_SCID;
5874 chan = NULL;
5875 goto response_unlock;
5876 }
5877
5878 /* Check if we already have channel with that dcid */
5879 if (__l2cap_get_chan_by_dcid(conn, scid)) {
5880 result = L2CAP_CR_LE_SCID_IN_USE;
5881 chan = NULL;
5882 goto response_unlock;
5883 }
5884
5885 chan = pchan->ops->new_connection(pchan);
5886 if (!chan) {
5887 result = L2CAP_CR_LE_NO_MEM;
5888 goto response_unlock;
5889 }
5890
5891 bacpy(&chan->src, &conn->hcon->src);
5892 bacpy(&chan->dst, &conn->hcon->dst);
5893 chan->src_type = bdaddr_src_type(conn->hcon);
5894 chan->dst_type = bdaddr_dst_type(conn->hcon);
5895 chan->psm = psm;
5896 chan->dcid = scid;
5897 chan->omtu = mtu;
5898 chan->remote_mps = mps;
5899
5900 __l2cap_chan_add(conn, chan);
5901
5902 l2cap_le_flowctl_init(chan, __le16_to_cpu(req->credits));
5903
5904 dcid = chan->scid;
5905 credits = chan->rx_credits;
5906
5907 __set_chan_timer(chan, chan->ops->get_sndtimeo(chan));
5908
5909 chan->ident = cmd->ident;
5910
5911 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) {
5912 l2cap_state_change(chan, BT_CONNECT2);
5913 /* The following result value is actually not defined
5914 * for LE CoC but we use it to let the function know
5915 * that it should bail out after doing its cleanup
5916 * instead of sending a response.
5917 */
5918 result = L2CAP_CR_PEND;
5919 chan->ops->defer(chan);
5920 } else {
5921 l2cap_chan_ready(chan);
5922 result = L2CAP_CR_LE_SUCCESS;
5923 }
5924
5925response_unlock:
5926 l2cap_chan_unlock(pchan);
5927 mutex_unlock(&conn->chan_lock);
5928 l2cap_chan_put(pchan);
5929
5930 if (result == L2CAP_CR_PEND)
5931 return 0;
5932
5933response:
5934 if (chan) {
5935 rsp.mtu = cpu_to_le16(chan->imtu);
5936 rsp.mps = cpu_to_le16(chan->mps);
5937 } else {
5938 rsp.mtu = 0;
5939 rsp.mps = 0;
5940 }
5941
5942 rsp.dcid = cpu_to_le16(dcid);
5943 rsp.credits = cpu_to_le16(credits);
5944 rsp.result = cpu_to_le16(result);
5945
5946 l2cap_send_cmd(conn, cmd->ident, L2CAP_LE_CONN_RSP, sizeof(rsp), &rsp);
5947
5948 return 0;
5949}
5950
5951static inline int l2cap_le_credits(struct l2cap_conn *conn,
5952 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5953 u8 *data)
5954{
5955 struct l2cap_le_credits *pkt;
5956 struct l2cap_chan *chan;
5957 u16 cid, credits, max_credits;
5958
5959 if (cmd_len != sizeof(*pkt))
5960 return -EPROTO;
5961
5962 pkt = (struct l2cap_le_credits *) data;
5963 cid = __le16_to_cpu(pkt->cid);
5964 credits = __le16_to_cpu(pkt->credits);
5965
5966 BT_DBG("cid 0x%4.4x credits 0x%4.4x", cid, credits);
5967
5968 chan = l2cap_get_chan_by_dcid(conn, cid);
5969 if (!chan)
5970 return -EBADSLT;
5971
5972 max_credits = LE_FLOWCTL_MAX_CREDITS - chan->tx_credits;
5973 if (credits > max_credits) {
5974 BT_ERR("LE credits overflow");
5975 l2cap_send_disconn_req(chan, ECONNRESET);
5976
5977 /* Return 0 so that we don't trigger an unnecessary
5978 * command reject packet.
5979 */
5980 goto unlock;
5981 }
5982
5983 chan->tx_credits += credits;
5984
5985 /* Resume sending */
5986 l2cap_le_flowctl_send(chan);
5987
5988 if (chan->tx_credits)
5989 chan->ops->resume(chan);
5990
5991unlock:
5992 l2cap_chan_unlock(chan);
5993 l2cap_chan_put(chan);
5994
5995 return 0;
5996}
5997
5998static inline int l2cap_ecred_conn_req(struct l2cap_conn *conn,
5999 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
6000 u8 *data)
6001{
6002 struct l2cap_ecred_conn_req *req = (void *) data;
6003 struct {
6004 struct l2cap_ecred_conn_rsp rsp;
6005 __le16 dcid[L2CAP_ECRED_MAX_CID];
6006 } __packed pdu;
6007 struct l2cap_chan *chan, *pchan;
6008 u16 mtu, mps;
6009 __le16 psm;
6010 u8 result, len = 0;
6011 int i, num_scid;
6012 bool defer = false;
6013
6014 if (!enable_ecred)
6015 return -EINVAL;
6016
6017 if (cmd_len < sizeof(*req) || (cmd_len - sizeof(*req)) % sizeof(u16)) {
6018 result = L2CAP_CR_LE_INVALID_PARAMS;
6019 goto response;
6020 }
6021
6022 cmd_len -= sizeof(*req);
6023 num_scid = cmd_len / sizeof(u16);
6024
6025 if (num_scid > ARRAY_SIZE(pdu.dcid)) {
6026 result = L2CAP_CR_LE_INVALID_PARAMS;
6027 goto response;
6028 }
6029
6030 mtu = __le16_to_cpu(req->mtu);
6031 mps = __le16_to_cpu(req->mps);
6032
6033 if (mtu < L2CAP_ECRED_MIN_MTU || mps < L2CAP_ECRED_MIN_MPS) {
6034 result = L2CAP_CR_LE_UNACCEPT_PARAMS;
6035 goto response;
6036 }
6037
6038 psm = req->psm;
6039
6040 /* BLUETOOTH CORE SPECIFICATION Version 5.3 | Vol 3, Part A
6041 * page 1059:
6042 *
6043 * Valid range: 0x0001-0x00ff
6044 *
6045 * Table 4.15: L2CAP_LE_CREDIT_BASED_CONNECTION_REQ SPSM ranges
6046 */
6047 if (!psm || __le16_to_cpu(psm) > L2CAP_PSM_LE_DYN_END) {
6048 result = L2CAP_CR_LE_BAD_PSM;
6049 goto response;
6050 }
6051
6052 BT_DBG("psm 0x%2.2x mtu %u mps %u", __le16_to_cpu(psm), mtu, mps);
6053
6054 memset(&pdu, 0, sizeof(pdu));
6055
6056 /* Check if we have socket listening on psm */
6057 pchan = l2cap_global_chan_by_psm(BT_LISTEN, psm, &conn->hcon->src,
6058 &conn->hcon->dst, LE_LINK);
6059 if (!pchan) {
6060 result = L2CAP_CR_LE_BAD_PSM;
6061 goto response;
6062 }
6063
6064 mutex_lock(&conn->chan_lock);
6065 l2cap_chan_lock(pchan);
6066
6067 if (!smp_sufficient_security(conn->hcon, pchan->sec_level,
6068 SMP_ALLOW_STK)) {
6069 result = L2CAP_CR_LE_AUTHENTICATION;
6070 goto unlock;
6071 }
6072
6073 result = L2CAP_CR_LE_SUCCESS;
6074
6075 for (i = 0; i < num_scid; i++) {
6076 u16 scid = __le16_to_cpu(req->scid[i]);
6077
6078 BT_DBG("scid[%d] 0x%4.4x", i, scid);
6079
6080 pdu.dcid[i] = 0x0000;
6081 len += sizeof(*pdu.dcid);
6082
6083 /* Check for valid dynamic CID range */
6084 if (scid < L2CAP_CID_DYN_START || scid > L2CAP_CID_LE_DYN_END) {
6085 result = L2CAP_CR_LE_INVALID_SCID;
6086 continue;
6087 }
6088
6089 /* Check if we already have channel with that dcid */
6090 if (__l2cap_get_chan_by_dcid(conn, scid)) {
6091 result = L2CAP_CR_LE_SCID_IN_USE;
6092 continue;
6093 }
6094
6095 chan = pchan->ops->new_connection(pchan);
6096 if (!chan) {
6097 result = L2CAP_CR_LE_NO_MEM;
6098 continue;
6099 }
6100
6101 bacpy(&chan->src, &conn->hcon->src);
6102 bacpy(&chan->dst, &conn->hcon->dst);
6103 chan->src_type = bdaddr_src_type(conn->hcon);
6104 chan->dst_type = bdaddr_dst_type(conn->hcon);
6105 chan->psm = psm;
6106 chan->dcid = scid;
6107 chan->omtu = mtu;
6108 chan->remote_mps = mps;
6109
6110 __l2cap_chan_add(conn, chan);
6111
6112 l2cap_ecred_init(chan, __le16_to_cpu(req->credits));
6113
6114 /* Init response */
6115 if (!pdu.rsp.credits) {
6116 pdu.rsp.mtu = cpu_to_le16(chan->imtu);
6117 pdu.rsp.mps = cpu_to_le16(chan->mps);
6118 pdu.rsp.credits = cpu_to_le16(chan->rx_credits);
6119 }
6120
6121 pdu.dcid[i] = cpu_to_le16(chan->scid);
6122
6123 __set_chan_timer(chan, chan->ops->get_sndtimeo(chan));
6124
6125 chan->ident = cmd->ident;
6126 chan->mode = L2CAP_MODE_EXT_FLOWCTL;
6127
6128 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) {
6129 l2cap_state_change(chan, BT_CONNECT2);
6130 defer = true;
6131 chan->ops->defer(chan);
6132 } else {
6133 l2cap_chan_ready(chan);
6134 }
6135 }
6136
6137unlock:
6138 l2cap_chan_unlock(pchan);
6139 mutex_unlock(&conn->chan_lock);
6140 l2cap_chan_put(pchan);
6141
6142response:
6143 pdu.rsp.result = cpu_to_le16(result);
6144
6145 if (defer)
6146 return 0;
6147
6148 l2cap_send_cmd(conn, cmd->ident, L2CAP_ECRED_CONN_RSP,
6149 sizeof(pdu.rsp) + len, &pdu);
6150
6151 return 0;
6152}
6153
6154static inline int l2cap_ecred_conn_rsp(struct l2cap_conn *conn,
6155 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
6156 u8 *data)
6157{
6158 struct l2cap_ecred_conn_rsp *rsp = (void *) data;
6159 struct hci_conn *hcon = conn->hcon;
6160 u16 mtu, mps, credits, result;
6161 struct l2cap_chan *chan, *tmp;
6162 int err = 0, sec_level;
6163 int i = 0;
6164
6165 if (cmd_len < sizeof(*rsp))
6166 return -EPROTO;
6167
6168 mtu = __le16_to_cpu(rsp->mtu);
6169 mps = __le16_to_cpu(rsp->mps);
6170 credits = __le16_to_cpu(rsp->credits);
6171 result = __le16_to_cpu(rsp->result);
6172
6173 BT_DBG("mtu %u mps %u credits %u result 0x%4.4x", mtu, mps, credits,
6174 result);
6175
6176 mutex_lock(&conn->chan_lock);
6177
6178 cmd_len -= sizeof(*rsp);
6179
6180 list_for_each_entry_safe(chan, tmp, &conn->chan_l, list) {
6181 u16 dcid;
6182
6183 if (chan->ident != cmd->ident ||
6184 chan->mode != L2CAP_MODE_EXT_FLOWCTL ||
6185 chan->state == BT_CONNECTED)
6186 continue;
6187
6188 l2cap_chan_lock(chan);
6189
6190 /* Check that there is a dcid for each pending channel */
6191 if (cmd_len < sizeof(dcid)) {
6192 l2cap_chan_del(chan, ECONNREFUSED);
6193 l2cap_chan_unlock(chan);
6194 continue;
6195 }
6196
6197 dcid = __le16_to_cpu(rsp->dcid[i++]);
6198 cmd_len -= sizeof(u16);
6199
6200 BT_DBG("dcid[%d] 0x%4.4x", i, dcid);
6201
6202 /* Check if dcid is already in use */
6203 if (dcid && __l2cap_get_chan_by_dcid(conn, dcid)) {
6204 /* If a device receives a
6205 * L2CAP_CREDIT_BASED_CONNECTION_RSP packet with an
6206 * already-assigned Destination CID, then both the
6207 * original channel and the new channel shall be
6208 * immediately discarded and not used.
6209 */
6210 l2cap_chan_del(chan, ECONNREFUSED);
6211 l2cap_chan_unlock(chan);
6212 chan = __l2cap_get_chan_by_dcid(conn, dcid);
6213 l2cap_chan_lock(chan);
6214 l2cap_chan_del(chan, ECONNRESET);
6215 l2cap_chan_unlock(chan);
6216 continue;
6217 }
6218
6219 switch (result) {
6220 case L2CAP_CR_LE_AUTHENTICATION:
6221 case L2CAP_CR_LE_ENCRYPTION:
6222 /* If we already have MITM protection we can't do
6223 * anything.
6224 */
6225 if (hcon->sec_level > BT_SECURITY_MEDIUM) {
6226 l2cap_chan_del(chan, ECONNREFUSED);
6227 break;
6228 }
6229
6230 sec_level = hcon->sec_level + 1;
6231 if (chan->sec_level < sec_level)
6232 chan->sec_level = sec_level;
6233
6234 /* We'll need to send a new Connect Request */
6235 clear_bit(FLAG_ECRED_CONN_REQ_SENT, &chan->flags);
6236
6237 smp_conn_security(hcon, chan->sec_level);
6238 break;
6239
6240 case L2CAP_CR_LE_BAD_PSM:
6241 l2cap_chan_del(chan, ECONNREFUSED);
6242 break;
6243
6244 default:
6245 /* If dcid was not set it means channels was refused */
6246 if (!dcid) {
6247 l2cap_chan_del(chan, ECONNREFUSED);
6248 break;
6249 }
6250
6251 chan->ident = 0;
6252 chan->dcid = dcid;
6253 chan->omtu = mtu;
6254 chan->remote_mps = mps;
6255 chan->tx_credits = credits;
6256 l2cap_chan_ready(chan);
6257 break;
6258 }
6259
6260 l2cap_chan_unlock(chan);
6261 }
6262
6263 mutex_unlock(&conn->chan_lock);
6264
6265 return err;
6266}
6267
6268static inline int l2cap_ecred_reconf_req(struct l2cap_conn *conn,
6269 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
6270 u8 *data)
6271{
6272 struct l2cap_ecred_reconf_req *req = (void *) data;
6273 struct l2cap_ecred_reconf_rsp rsp;
6274 u16 mtu, mps, result;
6275 struct l2cap_chan *chan;
6276 int i, num_scid;
6277
6278 if (!enable_ecred)
6279 return -EINVAL;
6280
6281 if (cmd_len < sizeof(*req) || cmd_len - sizeof(*req) % sizeof(u16)) {
6282 result = L2CAP_CR_LE_INVALID_PARAMS;
6283 goto respond;
6284 }
6285
6286 mtu = __le16_to_cpu(req->mtu);
6287 mps = __le16_to_cpu(req->mps);
6288
6289 BT_DBG("mtu %u mps %u", mtu, mps);
6290
6291 if (mtu < L2CAP_ECRED_MIN_MTU) {
6292 result = L2CAP_RECONF_INVALID_MTU;
6293 goto respond;
6294 }
6295
6296 if (mps < L2CAP_ECRED_MIN_MPS) {
6297 result = L2CAP_RECONF_INVALID_MPS;
6298 goto respond;
6299 }
6300
6301 cmd_len -= sizeof(*req);
6302 num_scid = cmd_len / sizeof(u16);
6303 result = L2CAP_RECONF_SUCCESS;
6304
6305 for (i = 0; i < num_scid; i++) {
6306 u16 scid;
6307
6308 scid = __le16_to_cpu(req->scid[i]);
6309 if (!scid)
6310 return -EPROTO;
6311
6312 chan = __l2cap_get_chan_by_dcid(conn, scid);
6313 if (!chan)
6314 continue;
6315
6316 /* If the MTU value is decreased for any of the included
6317 * channels, then the receiver shall disconnect all
6318 * included channels.
6319 */
6320 if (chan->omtu > mtu) {
6321 BT_ERR("chan %p decreased MTU %u -> %u", chan,
6322 chan->omtu, mtu);
6323 result = L2CAP_RECONF_INVALID_MTU;
6324 }
6325
6326 chan->omtu = mtu;
6327 chan->remote_mps = mps;
6328 }
6329
6330respond:
6331 rsp.result = cpu_to_le16(result);
6332
6333 l2cap_send_cmd(conn, cmd->ident, L2CAP_ECRED_RECONF_RSP, sizeof(rsp),
6334 &rsp);
6335
6336 return 0;
6337}
6338
6339static inline int l2cap_ecred_reconf_rsp(struct l2cap_conn *conn,
6340 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
6341 u8 *data)
6342{
6343 struct l2cap_chan *chan, *tmp;
6344 struct l2cap_ecred_conn_rsp *rsp = (void *) data;
6345 u16 result;
6346
6347 if (cmd_len < sizeof(*rsp))
6348 return -EPROTO;
6349
6350 result = __le16_to_cpu(rsp->result);
6351
6352 BT_DBG("result 0x%4.4x", rsp->result);
6353
6354 if (!result)
6355 return 0;
6356
6357 list_for_each_entry_safe(chan, tmp, &conn->chan_l, list) {
6358 if (chan->ident != cmd->ident)
6359 continue;
6360
6361 l2cap_chan_del(chan, ECONNRESET);
6362 }
6363
6364 return 0;
6365}
6366
6367static inline int l2cap_le_command_rej(struct l2cap_conn *conn,
6368 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
6369 u8 *data)
6370{
6371 struct l2cap_cmd_rej_unk *rej = (struct l2cap_cmd_rej_unk *) data;
6372 struct l2cap_chan *chan;
6373
6374 if (cmd_len < sizeof(*rej))
6375 return -EPROTO;
6376
6377 mutex_lock(&conn->chan_lock);
6378
6379 chan = __l2cap_get_chan_by_ident(conn, cmd->ident);
6380 if (!chan)
6381 goto done;
6382
6383 chan = l2cap_chan_hold_unless_zero(chan);
6384 if (!chan)
6385 goto done;
6386
6387 l2cap_chan_lock(chan);
6388 l2cap_chan_del(chan, ECONNREFUSED);
6389 l2cap_chan_unlock(chan);
6390 l2cap_chan_put(chan);
6391
6392done:
6393 mutex_unlock(&conn->chan_lock);
6394 return 0;
6395}
6396
6397static inline int l2cap_le_sig_cmd(struct l2cap_conn *conn,
6398 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
6399 u8 *data)
6400{
6401 int err = 0;
6402
6403 switch (cmd->code) {
6404 case L2CAP_COMMAND_REJ:
6405 l2cap_le_command_rej(conn, cmd, cmd_len, data);
6406 break;
6407
6408 case L2CAP_CONN_PARAM_UPDATE_REQ:
6409 err = l2cap_conn_param_update_req(conn, cmd, cmd_len, data);
6410 break;
6411
6412 case L2CAP_CONN_PARAM_UPDATE_RSP:
6413 break;
6414
6415 case L2CAP_LE_CONN_RSP:
6416 l2cap_le_connect_rsp(conn, cmd, cmd_len, data);
6417 break;
6418
6419 case L2CAP_LE_CONN_REQ:
6420 err = l2cap_le_connect_req(conn, cmd, cmd_len, data);
6421 break;
6422
6423 case L2CAP_LE_CREDITS:
6424 err = l2cap_le_credits(conn, cmd, cmd_len, data);
6425 break;
6426
6427 case L2CAP_ECRED_CONN_REQ:
6428 err = l2cap_ecred_conn_req(conn, cmd, cmd_len, data);
6429 break;
6430
6431 case L2CAP_ECRED_CONN_RSP:
6432 err = l2cap_ecred_conn_rsp(conn, cmd, cmd_len, data);
6433 break;
6434
6435 case L2CAP_ECRED_RECONF_REQ:
6436 err = l2cap_ecred_reconf_req(conn, cmd, cmd_len, data);
6437 break;
6438
6439 case L2CAP_ECRED_RECONF_RSP:
6440 err = l2cap_ecred_reconf_rsp(conn, cmd, cmd_len, data);
6441 break;
6442
6443 case L2CAP_DISCONN_REQ:
6444 err = l2cap_disconnect_req(conn, cmd, cmd_len, data);
6445 break;
6446
6447 case L2CAP_DISCONN_RSP:
6448 l2cap_disconnect_rsp(conn, cmd, cmd_len, data);
6449 break;
6450
6451 default:
6452 BT_ERR("Unknown LE signaling command 0x%2.2x", cmd->code);
6453 err = -EINVAL;
6454 break;
6455 }
6456
6457 return err;
6458}
6459
6460static inline void l2cap_le_sig_channel(struct l2cap_conn *conn,
6461 struct sk_buff *skb)
6462{
6463 struct hci_conn *hcon = conn->hcon;
6464 struct l2cap_cmd_hdr *cmd;
6465 u16 len;
6466 int err;
6467
6468 if (hcon->type != LE_LINK)
6469 goto drop;
6470
6471 if (skb->len < L2CAP_CMD_HDR_SIZE)
6472 goto drop;
6473
6474 cmd = (void *) skb->data;
6475 skb_pull(skb, L2CAP_CMD_HDR_SIZE);
6476
6477 len = le16_to_cpu(cmd->len);
6478
6479 BT_DBG("code 0x%2.2x len %d id 0x%2.2x", cmd->code, len, cmd->ident);
6480
6481 if (len != skb->len || !cmd->ident) {
6482 BT_DBG("corrupted command");
6483 goto drop;
6484 }
6485
6486 err = l2cap_le_sig_cmd(conn, cmd, len, skb->data);
6487 if (err) {
6488 struct l2cap_cmd_rej_unk rej;
6489
6490 BT_ERR("Wrong link type (%d)", err);
6491
6492 rej.reason = cpu_to_le16(L2CAP_REJ_NOT_UNDERSTOOD);
6493 l2cap_send_cmd(conn, cmd->ident, L2CAP_COMMAND_REJ,
6494 sizeof(rej), &rej);
6495 }
6496
6497drop:
6498 kfree_skb(skb);
6499}
6500
6501static inline void l2cap_sig_send_rej(struct l2cap_conn *conn, u16 ident)
6502{
6503 struct l2cap_cmd_rej_unk rej;
6504
6505 rej.reason = cpu_to_le16(L2CAP_REJ_NOT_UNDERSTOOD);
6506 l2cap_send_cmd(conn, ident, L2CAP_COMMAND_REJ, sizeof(rej), &rej);
6507}
6508
6509static inline void l2cap_sig_channel(struct l2cap_conn *conn,
6510 struct sk_buff *skb)
6511{
6512 struct hci_conn *hcon = conn->hcon;
6513 struct l2cap_cmd_hdr *cmd;
6514 int err;
6515
6516 l2cap_raw_recv(conn, skb);
6517
6518 if (hcon->type != ACL_LINK)
6519 goto drop;
6520
6521 while (skb->len >= L2CAP_CMD_HDR_SIZE) {
6522 u16 len;
6523
6524 cmd = (void *) skb->data;
6525 skb_pull(skb, L2CAP_CMD_HDR_SIZE);
6526
6527 len = le16_to_cpu(cmd->len);
6528
6529 BT_DBG("code 0x%2.2x len %d id 0x%2.2x", cmd->code, len,
6530 cmd->ident);
6531
6532 if (len > skb->len || !cmd->ident) {
6533 BT_DBG("corrupted command");
6534 l2cap_sig_send_rej(conn, cmd->ident);
6535 skb_pull(skb, len > skb->len ? skb->len : len);
6536 continue;
6537 }
6538
6539 err = l2cap_bredr_sig_cmd(conn, cmd, len, skb->data);
6540 if (err) {
6541 BT_ERR("Wrong link type (%d)", err);
6542 l2cap_sig_send_rej(conn, cmd->ident);
6543 }
6544
6545 skb_pull(skb, len);
6546 }
6547
6548 if (skb->len > 0) {
6549 BT_DBG("corrupted command");
6550 l2cap_sig_send_rej(conn, 0);
6551 }
6552
6553drop:
6554 kfree_skb(skb);
6555}
6556
6557static int l2cap_check_fcs(struct l2cap_chan *chan, struct sk_buff *skb)
6558{
6559 u16 our_fcs, rcv_fcs;
6560 int hdr_size;
6561
6562 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
6563 hdr_size = L2CAP_EXT_HDR_SIZE;
6564 else
6565 hdr_size = L2CAP_ENH_HDR_SIZE;
6566
6567 if (chan->fcs == L2CAP_FCS_CRC16) {
6568 skb_trim(skb, skb->len - L2CAP_FCS_SIZE);
6569 rcv_fcs = get_unaligned_le16(skb->data + skb->len);
6570 our_fcs = crc16(0, skb->data - hdr_size, skb->len + hdr_size);
6571
6572 if (our_fcs != rcv_fcs)
6573 return -EBADMSG;
6574 }
6575 return 0;
6576}
6577
6578static void l2cap_send_i_or_rr_or_rnr(struct l2cap_chan *chan)
6579{
6580 struct l2cap_ctrl control;
6581
6582 BT_DBG("chan %p", chan);
6583
6584 memset(&control, 0, sizeof(control));
6585 control.sframe = 1;
6586 control.final = 1;
6587 control.reqseq = chan->buffer_seq;
6588 set_bit(CONN_SEND_FBIT, &chan->conn_state);
6589
6590 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
6591 control.super = L2CAP_SUPER_RNR;
6592 l2cap_send_sframe(chan, &control);
6593 }
6594
6595 if (test_and_clear_bit(CONN_REMOTE_BUSY, &chan->conn_state) &&
6596 chan->unacked_frames > 0)
6597 __set_retrans_timer(chan);
6598
6599 /* Send pending iframes */
6600 l2cap_ertm_send(chan);
6601
6602 if (!test_bit(CONN_LOCAL_BUSY, &chan->conn_state) &&
6603 test_bit(CONN_SEND_FBIT, &chan->conn_state)) {
6604 /* F-bit wasn't sent in an s-frame or i-frame yet, so
6605 * send it now.
6606 */
6607 control.super = L2CAP_SUPER_RR;
6608 l2cap_send_sframe(chan, &control);
6609 }
6610}
6611
6612static void append_skb_frag(struct sk_buff *skb, struct sk_buff *new_frag,
6613 struct sk_buff **last_frag)
6614{
6615 /* skb->len reflects data in skb as well as all fragments
6616 * skb->data_len reflects only data in fragments
6617 */
6618 if (!skb_has_frag_list(skb))
6619 skb_shinfo(skb)->frag_list = new_frag;
6620
6621 new_frag->next = NULL;
6622
6623 (*last_frag)->next = new_frag;
6624 *last_frag = new_frag;
6625
6626 skb->len += new_frag->len;
6627 skb->data_len += new_frag->len;
6628 skb->truesize += new_frag->truesize;
6629}
6630
6631static int l2cap_reassemble_sdu(struct l2cap_chan *chan, struct sk_buff *skb,
6632 struct l2cap_ctrl *control)
6633{
6634 int err = -EINVAL;
6635
6636 switch (control->sar) {
6637 case L2CAP_SAR_UNSEGMENTED:
6638 if (chan->sdu)
6639 break;
6640
6641 err = chan->ops->recv(chan, skb);
6642 break;
6643
6644 case L2CAP_SAR_START:
6645 if (chan->sdu)
6646 break;
6647
6648 if (!pskb_may_pull(skb, L2CAP_SDULEN_SIZE))
6649 break;
6650
6651 chan->sdu_len = get_unaligned_le16(skb->data);
6652 skb_pull(skb, L2CAP_SDULEN_SIZE);
6653
6654 if (chan->sdu_len > chan->imtu) {
6655 err = -EMSGSIZE;
6656 break;
6657 }
6658
6659 if (skb->len >= chan->sdu_len)
6660 break;
6661
6662 chan->sdu = skb;
6663 chan->sdu_last_frag = skb;
6664
6665 skb = NULL;
6666 err = 0;
6667 break;
6668
6669 case L2CAP_SAR_CONTINUE:
6670 if (!chan->sdu)
6671 break;
6672
6673 append_skb_frag(chan->sdu, skb,
6674 &chan->sdu_last_frag);
6675 skb = NULL;
6676
6677 if (chan->sdu->len >= chan->sdu_len)
6678 break;
6679
6680 err = 0;
6681 break;
6682
6683 case L2CAP_SAR_END:
6684 if (!chan->sdu)
6685 break;
6686
6687 append_skb_frag(chan->sdu, skb,
6688 &chan->sdu_last_frag);
6689 skb = NULL;
6690
6691 if (chan->sdu->len != chan->sdu_len)
6692 break;
6693
6694 err = chan->ops->recv(chan, chan->sdu);
6695
6696 if (!err) {
6697 /* Reassembly complete */
6698 chan->sdu = NULL;
6699 chan->sdu_last_frag = NULL;
6700 chan->sdu_len = 0;
6701 }
6702 break;
6703 }
6704
6705 if (err) {
6706 kfree_skb(skb);
6707 kfree_skb(chan->sdu);
6708 chan->sdu = NULL;
6709 chan->sdu_last_frag = NULL;
6710 chan->sdu_len = 0;
6711 }
6712
6713 return err;
6714}
6715
6716static int l2cap_resegment(struct l2cap_chan *chan)
6717{
6718 /* Placeholder */
6719 return 0;
6720}
6721
6722void l2cap_chan_busy(struct l2cap_chan *chan, int busy)
6723{
6724 u8 event;
6725
6726 if (chan->mode != L2CAP_MODE_ERTM)
6727 return;
6728
6729 event = busy ? L2CAP_EV_LOCAL_BUSY_DETECTED : L2CAP_EV_LOCAL_BUSY_CLEAR;
6730 l2cap_tx(chan, NULL, NULL, event);
6731}
6732
6733static int l2cap_rx_queued_iframes(struct l2cap_chan *chan)
6734{
6735 int err = 0;
6736 /* Pass sequential frames to l2cap_reassemble_sdu()
6737 * until a gap is encountered.
6738 */
6739
6740 BT_DBG("chan %p", chan);
6741
6742 while (!test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
6743 struct sk_buff *skb;
6744 BT_DBG("Searching for skb with txseq %d (queue len %d)",
6745 chan->buffer_seq, skb_queue_len(&chan->srej_q));
6746
6747 skb = l2cap_ertm_seq_in_queue(&chan->srej_q, chan->buffer_seq);
6748
6749 if (!skb)
6750 break;
6751
6752 skb_unlink(skb, &chan->srej_q);
6753 chan->buffer_seq = __next_seq(chan, chan->buffer_seq);
6754 err = l2cap_reassemble_sdu(chan, skb, &bt_cb(skb)->l2cap);
6755 if (err)
6756 break;
6757 }
6758
6759 if (skb_queue_empty(&chan->srej_q)) {
6760 chan->rx_state = L2CAP_RX_STATE_RECV;
6761 l2cap_send_ack(chan);
6762 }
6763
6764 return err;
6765}
6766
6767static void l2cap_handle_srej(struct l2cap_chan *chan,
6768 struct l2cap_ctrl *control)
6769{
6770 struct sk_buff *skb;
6771
6772 BT_DBG("chan %p, control %p", chan, control);
6773
6774 if (control->reqseq == chan->next_tx_seq) {
6775 BT_DBG("Invalid reqseq %d, disconnecting", control->reqseq);
6776 l2cap_send_disconn_req(chan, ECONNRESET);
6777 return;
6778 }
6779
6780 skb = l2cap_ertm_seq_in_queue(&chan->tx_q, control->reqseq);
6781
6782 if (skb == NULL) {
6783 BT_DBG("Seq %d not available for retransmission",
6784 control->reqseq);
6785 return;
6786 }
6787
6788 if (chan->max_tx != 0 && bt_cb(skb)->l2cap.retries >= chan->max_tx) {
6789 BT_DBG("Retry limit exceeded (%d)", chan->max_tx);
6790 l2cap_send_disconn_req(chan, ECONNRESET);
6791 return;
6792 }
6793
6794 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6795
6796 if (control->poll) {
6797 l2cap_pass_to_tx(chan, control);
6798
6799 set_bit(CONN_SEND_FBIT, &chan->conn_state);
6800 l2cap_retransmit(chan, control);
6801 l2cap_ertm_send(chan);
6802
6803 if (chan->tx_state == L2CAP_TX_STATE_WAIT_F) {
6804 set_bit(CONN_SREJ_ACT, &chan->conn_state);
6805 chan->srej_save_reqseq = control->reqseq;
6806 }
6807 } else {
6808 l2cap_pass_to_tx_fbit(chan, control);
6809
6810 if (control->final) {
6811 if (chan->srej_save_reqseq != control->reqseq ||
6812 !test_and_clear_bit(CONN_SREJ_ACT,
6813 &chan->conn_state))
6814 l2cap_retransmit(chan, control);
6815 } else {
6816 l2cap_retransmit(chan, control);
6817 if (chan->tx_state == L2CAP_TX_STATE_WAIT_F) {
6818 set_bit(CONN_SREJ_ACT, &chan->conn_state);
6819 chan->srej_save_reqseq = control->reqseq;
6820 }
6821 }
6822 }
6823}
6824
6825static void l2cap_handle_rej(struct l2cap_chan *chan,
6826 struct l2cap_ctrl *control)
6827{
6828 struct sk_buff *skb;
6829
6830 BT_DBG("chan %p, control %p", chan, control);
6831
6832 if (control->reqseq == chan->next_tx_seq) {
6833 BT_DBG("Invalid reqseq %d, disconnecting", control->reqseq);
6834 l2cap_send_disconn_req(chan, ECONNRESET);
6835 return;
6836 }
6837
6838 skb = l2cap_ertm_seq_in_queue(&chan->tx_q, control->reqseq);
6839
6840 if (chan->max_tx && skb &&
6841 bt_cb(skb)->l2cap.retries >= chan->max_tx) {
6842 BT_DBG("Retry limit exceeded (%d)", chan->max_tx);
6843 l2cap_send_disconn_req(chan, ECONNRESET);
6844 return;
6845 }
6846
6847 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6848
6849 l2cap_pass_to_tx(chan, control);
6850
6851 if (control->final) {
6852 if (!test_and_clear_bit(CONN_REJ_ACT, &chan->conn_state))
6853 l2cap_retransmit_all(chan, control);
6854 } else {
6855 l2cap_retransmit_all(chan, control);
6856 l2cap_ertm_send(chan);
6857 if (chan->tx_state == L2CAP_TX_STATE_WAIT_F)
6858 set_bit(CONN_REJ_ACT, &chan->conn_state);
6859 }
6860}
6861
6862static u8 l2cap_classify_txseq(struct l2cap_chan *chan, u16 txseq)
6863{
6864 BT_DBG("chan %p, txseq %d", chan, txseq);
6865
6866 BT_DBG("last_acked_seq %d, expected_tx_seq %d", chan->last_acked_seq,
6867 chan->expected_tx_seq);
6868
6869 if (chan->rx_state == L2CAP_RX_STATE_SREJ_SENT) {
6870 if (__seq_offset(chan, txseq, chan->last_acked_seq) >=
6871 chan->tx_win) {
6872 /* See notes below regarding "double poll" and
6873 * invalid packets.
6874 */
6875 if (chan->tx_win <= ((chan->tx_win_max + 1) >> 1)) {
6876 BT_DBG("Invalid/Ignore - after SREJ");
6877 return L2CAP_TXSEQ_INVALID_IGNORE;
6878 } else {
6879 BT_DBG("Invalid - in window after SREJ sent");
6880 return L2CAP_TXSEQ_INVALID;
6881 }
6882 }
6883
6884 if (chan->srej_list.head == txseq) {
6885 BT_DBG("Expected SREJ");
6886 return L2CAP_TXSEQ_EXPECTED_SREJ;
6887 }
6888
6889 if (l2cap_ertm_seq_in_queue(&chan->srej_q, txseq)) {
6890 BT_DBG("Duplicate SREJ - txseq already stored");
6891 return L2CAP_TXSEQ_DUPLICATE_SREJ;
6892 }
6893
6894 if (l2cap_seq_list_contains(&chan->srej_list, txseq)) {
6895 BT_DBG("Unexpected SREJ - not requested");
6896 return L2CAP_TXSEQ_UNEXPECTED_SREJ;
6897 }
6898 }
6899
6900 if (chan->expected_tx_seq == txseq) {
6901 if (__seq_offset(chan, txseq, chan->last_acked_seq) >=
6902 chan->tx_win) {
6903 BT_DBG("Invalid - txseq outside tx window");
6904 return L2CAP_TXSEQ_INVALID;
6905 } else {
6906 BT_DBG("Expected");
6907 return L2CAP_TXSEQ_EXPECTED;
6908 }
6909 }
6910
6911 if (__seq_offset(chan, txseq, chan->last_acked_seq) <
6912 __seq_offset(chan, chan->expected_tx_seq, chan->last_acked_seq)) {
6913 BT_DBG("Duplicate - expected_tx_seq later than txseq");
6914 return L2CAP_TXSEQ_DUPLICATE;
6915 }
6916
6917 if (__seq_offset(chan, txseq, chan->last_acked_seq) >= chan->tx_win) {
6918 /* A source of invalid packets is a "double poll" condition,
6919 * where delays cause us to send multiple poll packets. If
6920 * the remote stack receives and processes both polls,
6921 * sequence numbers can wrap around in such a way that a
6922 * resent frame has a sequence number that looks like new data
6923 * with a sequence gap. This would trigger an erroneous SREJ
6924 * request.
6925 *
6926 * Fortunately, this is impossible with a tx window that's
6927 * less than half of the maximum sequence number, which allows
6928 * invalid frames to be safely ignored.
6929 *
6930 * With tx window sizes greater than half of the tx window
6931 * maximum, the frame is invalid and cannot be ignored. This
6932 * causes a disconnect.
6933 */
6934
6935 if (chan->tx_win <= ((chan->tx_win_max + 1) >> 1)) {
6936 BT_DBG("Invalid/Ignore - txseq outside tx window");
6937 return L2CAP_TXSEQ_INVALID_IGNORE;
6938 } else {
6939 BT_DBG("Invalid - txseq outside tx window");
6940 return L2CAP_TXSEQ_INVALID;
6941 }
6942 } else {
6943 BT_DBG("Unexpected - txseq indicates missing frames");
6944 return L2CAP_TXSEQ_UNEXPECTED;
6945 }
6946}
6947
6948static int l2cap_rx_state_recv(struct l2cap_chan *chan,
6949 struct l2cap_ctrl *control,
6950 struct sk_buff *skb, u8 event)
6951{
6952 struct l2cap_ctrl local_control;
6953 int err = 0;
6954 bool skb_in_use = false;
6955
6956 BT_DBG("chan %p, control %p, skb %p, event %d", chan, control, skb,
6957 event);
6958
6959 switch (event) {
6960 case L2CAP_EV_RECV_IFRAME:
6961 switch (l2cap_classify_txseq(chan, control->txseq)) {
6962 case L2CAP_TXSEQ_EXPECTED:
6963 l2cap_pass_to_tx(chan, control);
6964
6965 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
6966 BT_DBG("Busy, discarding expected seq %d",
6967 control->txseq);
6968 break;
6969 }
6970
6971 chan->expected_tx_seq = __next_seq(chan,
6972 control->txseq);
6973
6974 chan->buffer_seq = chan->expected_tx_seq;
6975 skb_in_use = true;
6976
6977 /* l2cap_reassemble_sdu may free skb, hence invalidate
6978 * control, so make a copy in advance to use it after
6979 * l2cap_reassemble_sdu returns and to avoid the race
6980 * condition, for example:
6981 *
6982 * The current thread calls:
6983 * l2cap_reassemble_sdu
6984 * chan->ops->recv == l2cap_sock_recv_cb
6985 * __sock_queue_rcv_skb
6986 * Another thread calls:
6987 * bt_sock_recvmsg
6988 * skb_recv_datagram
6989 * skb_free_datagram
6990 * Then the current thread tries to access control, but
6991 * it was freed by skb_free_datagram.
6992 */
6993 local_control = *control;
6994 err = l2cap_reassemble_sdu(chan, skb, control);
6995 if (err)
6996 break;
6997
6998 if (local_control.final) {
6999 if (!test_and_clear_bit(CONN_REJ_ACT,
7000 &chan->conn_state)) {
7001 local_control.final = 0;
7002 l2cap_retransmit_all(chan, &local_control);
7003 l2cap_ertm_send(chan);
7004 }
7005 }
7006
7007 if (!test_bit(CONN_LOCAL_BUSY, &chan->conn_state))
7008 l2cap_send_ack(chan);
7009 break;
7010 case L2CAP_TXSEQ_UNEXPECTED:
7011 l2cap_pass_to_tx(chan, control);
7012
7013 /* Can't issue SREJ frames in the local busy state.
7014 * Drop this frame, it will be seen as missing
7015 * when local busy is exited.
7016 */
7017 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
7018 BT_DBG("Busy, discarding unexpected seq %d",
7019 control->txseq);
7020 break;
7021 }
7022
7023 /* There was a gap in the sequence, so an SREJ
7024 * must be sent for each missing frame. The
7025 * current frame is stored for later use.
7026 */
7027 skb_queue_tail(&chan->srej_q, skb);
7028 skb_in_use = true;
7029 BT_DBG("Queued %p (queue len %d)", skb,
7030 skb_queue_len(&chan->srej_q));
7031
7032 clear_bit(CONN_SREJ_ACT, &chan->conn_state);
7033 l2cap_seq_list_clear(&chan->srej_list);
7034 l2cap_send_srej(chan, control->txseq);
7035
7036 chan->rx_state = L2CAP_RX_STATE_SREJ_SENT;
7037 break;
7038 case L2CAP_TXSEQ_DUPLICATE:
7039 l2cap_pass_to_tx(chan, control);
7040 break;
7041 case L2CAP_TXSEQ_INVALID_IGNORE:
7042 break;
7043 case L2CAP_TXSEQ_INVALID:
7044 default:
7045 l2cap_send_disconn_req(chan, ECONNRESET);
7046 break;
7047 }
7048 break;
7049 case L2CAP_EV_RECV_RR:
7050 l2cap_pass_to_tx(chan, control);
7051 if (control->final) {
7052 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
7053
7054 if (!test_and_clear_bit(CONN_REJ_ACT, &chan->conn_state) &&
7055 !__chan_is_moving(chan)) {
7056 control->final = 0;
7057 l2cap_retransmit_all(chan, control);
7058 }
7059
7060 l2cap_ertm_send(chan);
7061 } else if (control->poll) {
7062 l2cap_send_i_or_rr_or_rnr(chan);
7063 } else {
7064 if (test_and_clear_bit(CONN_REMOTE_BUSY,
7065 &chan->conn_state) &&
7066 chan->unacked_frames)
7067 __set_retrans_timer(chan);
7068
7069 l2cap_ertm_send(chan);
7070 }
7071 break;
7072 case L2CAP_EV_RECV_RNR:
7073 set_bit(CONN_REMOTE_BUSY, &chan->conn_state);
7074 l2cap_pass_to_tx(chan, control);
7075 if (control && control->poll) {
7076 set_bit(CONN_SEND_FBIT, &chan->conn_state);
7077 l2cap_send_rr_or_rnr(chan, 0);
7078 }
7079 __clear_retrans_timer(chan);
7080 l2cap_seq_list_clear(&chan->retrans_list);
7081 break;
7082 case L2CAP_EV_RECV_REJ:
7083 l2cap_handle_rej(chan, control);
7084 break;
7085 case L2CAP_EV_RECV_SREJ:
7086 l2cap_handle_srej(chan, control);
7087 break;
7088 default:
7089 break;
7090 }
7091
7092 if (skb && !skb_in_use) {
7093 BT_DBG("Freeing %p", skb);
7094 kfree_skb(skb);
7095 }
7096
7097 return err;
7098}
7099
7100static int l2cap_rx_state_srej_sent(struct l2cap_chan *chan,
7101 struct l2cap_ctrl *control,
7102 struct sk_buff *skb, u8 event)
7103{
7104 int err = 0;
7105 u16 txseq = control->txseq;
7106 bool skb_in_use = false;
7107
7108 BT_DBG("chan %p, control %p, skb %p, event %d", chan, control, skb,
7109 event);
7110
7111 switch (event) {
7112 case L2CAP_EV_RECV_IFRAME:
7113 switch (l2cap_classify_txseq(chan, txseq)) {
7114 case L2CAP_TXSEQ_EXPECTED:
7115 /* Keep frame for reassembly later */
7116 l2cap_pass_to_tx(chan, control);
7117 skb_queue_tail(&chan->srej_q, skb);
7118 skb_in_use = true;
7119 BT_DBG("Queued %p (queue len %d)", skb,
7120 skb_queue_len(&chan->srej_q));
7121
7122 chan->expected_tx_seq = __next_seq(chan, txseq);
7123 break;
7124 case L2CAP_TXSEQ_EXPECTED_SREJ:
7125 l2cap_seq_list_pop(&chan->srej_list);
7126
7127 l2cap_pass_to_tx(chan, control);
7128 skb_queue_tail(&chan->srej_q, skb);
7129 skb_in_use = true;
7130 BT_DBG("Queued %p (queue len %d)", skb,
7131 skb_queue_len(&chan->srej_q));
7132
7133 err = l2cap_rx_queued_iframes(chan);
7134 if (err)
7135 break;
7136
7137 break;
7138 case L2CAP_TXSEQ_UNEXPECTED:
7139 /* Got a frame that can't be reassembled yet.
7140 * Save it for later, and send SREJs to cover
7141 * the missing frames.
7142 */
7143 skb_queue_tail(&chan->srej_q, skb);
7144 skb_in_use = true;
7145 BT_DBG("Queued %p (queue len %d)", skb,
7146 skb_queue_len(&chan->srej_q));
7147
7148 l2cap_pass_to_tx(chan, control);
7149 l2cap_send_srej(chan, control->txseq);
7150 break;
7151 case L2CAP_TXSEQ_UNEXPECTED_SREJ:
7152 /* This frame was requested with an SREJ, but
7153 * some expected retransmitted frames are
7154 * missing. Request retransmission of missing
7155 * SREJ'd frames.
7156 */
7157 skb_queue_tail(&chan->srej_q, skb);
7158 skb_in_use = true;
7159 BT_DBG("Queued %p (queue len %d)", skb,
7160 skb_queue_len(&chan->srej_q));
7161
7162 l2cap_pass_to_tx(chan, control);
7163 l2cap_send_srej_list(chan, control->txseq);
7164 break;
7165 case L2CAP_TXSEQ_DUPLICATE_SREJ:
7166 /* We've already queued this frame. Drop this copy. */
7167 l2cap_pass_to_tx(chan, control);
7168 break;
7169 case L2CAP_TXSEQ_DUPLICATE:
7170 /* Expecting a later sequence number, so this frame
7171 * was already received. Ignore it completely.
7172 */
7173 break;
7174 case L2CAP_TXSEQ_INVALID_IGNORE:
7175 break;
7176 case L2CAP_TXSEQ_INVALID:
7177 default:
7178 l2cap_send_disconn_req(chan, ECONNRESET);
7179 break;
7180 }
7181 break;
7182 case L2CAP_EV_RECV_RR:
7183 l2cap_pass_to_tx(chan, control);
7184 if (control->final) {
7185 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
7186
7187 if (!test_and_clear_bit(CONN_REJ_ACT,
7188 &chan->conn_state)) {
7189 control->final = 0;
7190 l2cap_retransmit_all(chan, control);
7191 }
7192
7193 l2cap_ertm_send(chan);
7194 } else if (control->poll) {
7195 if (test_and_clear_bit(CONN_REMOTE_BUSY,
7196 &chan->conn_state) &&
7197 chan->unacked_frames) {
7198 __set_retrans_timer(chan);
7199 }
7200
7201 set_bit(CONN_SEND_FBIT, &chan->conn_state);
7202 l2cap_send_srej_tail(chan);
7203 } else {
7204 if (test_and_clear_bit(CONN_REMOTE_BUSY,
7205 &chan->conn_state) &&
7206 chan->unacked_frames)
7207 __set_retrans_timer(chan);
7208
7209 l2cap_send_ack(chan);
7210 }
7211 break;
7212 case L2CAP_EV_RECV_RNR:
7213 set_bit(CONN_REMOTE_BUSY, &chan->conn_state);
7214 l2cap_pass_to_tx(chan, control);
7215 if (control->poll) {
7216 l2cap_send_srej_tail(chan);
7217 } else {
7218 struct l2cap_ctrl rr_control;
7219 memset(&rr_control, 0, sizeof(rr_control));
7220 rr_control.sframe = 1;
7221 rr_control.super = L2CAP_SUPER_RR;
7222 rr_control.reqseq = chan->buffer_seq;
7223 l2cap_send_sframe(chan, &rr_control);
7224 }
7225
7226 break;
7227 case L2CAP_EV_RECV_REJ:
7228 l2cap_handle_rej(chan, control);
7229 break;
7230 case L2CAP_EV_RECV_SREJ:
7231 l2cap_handle_srej(chan, control);
7232 break;
7233 }
7234
7235 if (skb && !skb_in_use) {
7236 BT_DBG("Freeing %p", skb);
7237 kfree_skb(skb);
7238 }
7239
7240 return err;
7241}
7242
7243static int l2cap_finish_move(struct l2cap_chan *chan)
7244{
7245 BT_DBG("chan %p", chan);
7246
7247 chan->rx_state = L2CAP_RX_STATE_RECV;
7248
7249 if (chan->hs_hcon)
7250 chan->conn->mtu = chan->hs_hcon->hdev->block_mtu;
7251 else
7252 chan->conn->mtu = chan->conn->hcon->hdev->acl_mtu;
7253
7254 return l2cap_resegment(chan);
7255}
7256
7257static int l2cap_rx_state_wait_p(struct l2cap_chan *chan,
7258 struct l2cap_ctrl *control,
7259 struct sk_buff *skb, u8 event)
7260{
7261 int err;
7262
7263 BT_DBG("chan %p, control %p, skb %p, event %d", chan, control, skb,
7264 event);
7265
7266 if (!control->poll)
7267 return -EPROTO;
7268
7269 l2cap_process_reqseq(chan, control->reqseq);
7270
7271 if (!skb_queue_empty(&chan->tx_q))
7272 chan->tx_send_head = skb_peek(&chan->tx_q);
7273 else
7274 chan->tx_send_head = NULL;
7275
7276 /* Rewind next_tx_seq to the point expected
7277 * by the receiver.
7278 */
7279 chan->next_tx_seq = control->reqseq;
7280 chan->unacked_frames = 0;
7281
7282 err = l2cap_finish_move(chan);
7283 if (err)
7284 return err;
7285
7286 set_bit(CONN_SEND_FBIT, &chan->conn_state);
7287 l2cap_send_i_or_rr_or_rnr(chan);
7288
7289 if (event == L2CAP_EV_RECV_IFRAME)
7290 return -EPROTO;
7291
7292 return l2cap_rx_state_recv(chan, control, NULL, event);
7293}
7294
7295static int l2cap_rx_state_wait_f(struct l2cap_chan *chan,
7296 struct l2cap_ctrl *control,
7297 struct sk_buff *skb, u8 event)
7298{
7299 int err;
7300
7301 if (!control->final)
7302 return -EPROTO;
7303
7304 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
7305
7306 chan->rx_state = L2CAP_RX_STATE_RECV;
7307 l2cap_process_reqseq(chan, control->reqseq);
7308
7309 if (!skb_queue_empty(&chan->tx_q))
7310 chan->tx_send_head = skb_peek(&chan->tx_q);
7311 else
7312 chan->tx_send_head = NULL;
7313
7314 /* Rewind next_tx_seq to the point expected
7315 * by the receiver.
7316 */
7317 chan->next_tx_seq = control->reqseq;
7318 chan->unacked_frames = 0;
7319
7320 if (chan->hs_hcon)
7321 chan->conn->mtu = chan->hs_hcon->hdev->block_mtu;
7322 else
7323 chan->conn->mtu = chan->conn->hcon->hdev->acl_mtu;
7324
7325 err = l2cap_resegment(chan);
7326
7327 if (!err)
7328 err = l2cap_rx_state_recv(chan, control, skb, event);
7329
7330 return err;
7331}
7332
7333static bool __valid_reqseq(struct l2cap_chan *chan, u16 reqseq)
7334{
7335 /* Make sure reqseq is for a packet that has been sent but not acked */
7336 u16 unacked;
7337
7338 unacked = __seq_offset(chan, chan->next_tx_seq, chan->expected_ack_seq);
7339 return __seq_offset(chan, chan->next_tx_seq, reqseq) <= unacked;
7340}
7341
7342static int l2cap_rx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
7343 struct sk_buff *skb, u8 event)
7344{
7345 int err = 0;
7346
7347 BT_DBG("chan %p, control %p, skb %p, event %d, state %d", chan,
7348 control, skb, event, chan->rx_state);
7349
7350 if (__valid_reqseq(chan, control->reqseq)) {
7351 switch (chan->rx_state) {
7352 case L2CAP_RX_STATE_RECV:
7353 err = l2cap_rx_state_recv(chan, control, skb, event);
7354 break;
7355 case L2CAP_RX_STATE_SREJ_SENT:
7356 err = l2cap_rx_state_srej_sent(chan, control, skb,
7357 event);
7358 break;
7359 case L2CAP_RX_STATE_WAIT_P:
7360 err = l2cap_rx_state_wait_p(chan, control, skb, event);
7361 break;
7362 case L2CAP_RX_STATE_WAIT_F:
7363 err = l2cap_rx_state_wait_f(chan, control, skb, event);
7364 break;
7365 default:
7366 /* shut it down */
7367 break;
7368 }
7369 } else {
7370 BT_DBG("Invalid reqseq %d (next_tx_seq %d, expected_ack_seq %d",
7371 control->reqseq, chan->next_tx_seq,
7372 chan->expected_ack_seq);
7373 l2cap_send_disconn_req(chan, ECONNRESET);
7374 }
7375
7376 return err;
7377}
7378
7379static int l2cap_stream_rx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
7380 struct sk_buff *skb)
7381{
7382 /* l2cap_reassemble_sdu may free skb, hence invalidate control, so store
7383 * the txseq field in advance to use it after l2cap_reassemble_sdu
7384 * returns and to avoid the race condition, for example:
7385 *
7386 * The current thread calls:
7387 * l2cap_reassemble_sdu
7388 * chan->ops->recv == l2cap_sock_recv_cb
7389 * __sock_queue_rcv_skb
7390 * Another thread calls:
7391 * bt_sock_recvmsg
7392 * skb_recv_datagram
7393 * skb_free_datagram
7394 * Then the current thread tries to access control, but it was freed by
7395 * skb_free_datagram.
7396 */
7397 u16 txseq = control->txseq;
7398
7399 BT_DBG("chan %p, control %p, skb %p, state %d", chan, control, skb,
7400 chan->rx_state);
7401
7402 if (l2cap_classify_txseq(chan, txseq) == L2CAP_TXSEQ_EXPECTED) {
7403 l2cap_pass_to_tx(chan, control);
7404
7405 BT_DBG("buffer_seq %u->%u", chan->buffer_seq,
7406 __next_seq(chan, chan->buffer_seq));
7407
7408 chan->buffer_seq = __next_seq(chan, chan->buffer_seq);
7409
7410 l2cap_reassemble_sdu(chan, skb, control);
7411 } else {
7412 if (chan->sdu) {
7413 kfree_skb(chan->sdu);
7414 chan->sdu = NULL;
7415 }
7416 chan->sdu_last_frag = NULL;
7417 chan->sdu_len = 0;
7418
7419 if (skb) {
7420 BT_DBG("Freeing %p", skb);
7421 kfree_skb(skb);
7422 }
7423 }
7424
7425 chan->last_acked_seq = txseq;
7426 chan->expected_tx_seq = __next_seq(chan, txseq);
7427
7428 return 0;
7429}
7430
7431static int l2cap_data_rcv(struct l2cap_chan *chan, struct sk_buff *skb)
7432{
7433 struct l2cap_ctrl *control = &bt_cb(skb)->l2cap;
7434 u16 len;
7435 u8 event;
7436
7437 __unpack_control(chan, skb);
7438
7439 len = skb->len;
7440
7441 /*
7442 * We can just drop the corrupted I-frame here.
7443 * Receiver will miss it and start proper recovery
7444 * procedures and ask for retransmission.
7445 */
7446 if (l2cap_check_fcs(chan, skb))
7447 goto drop;
7448
7449 if (!control->sframe && control->sar == L2CAP_SAR_START)
7450 len -= L2CAP_SDULEN_SIZE;
7451
7452 if (chan->fcs == L2CAP_FCS_CRC16)
7453 len -= L2CAP_FCS_SIZE;
7454
7455 if (len > chan->mps) {
7456 l2cap_send_disconn_req(chan, ECONNRESET);
7457 goto drop;
7458 }
7459
7460 if (chan->ops->filter) {
7461 if (chan->ops->filter(chan, skb))
7462 goto drop;
7463 }
7464
7465 if (!control->sframe) {
7466 int err;
7467
7468 BT_DBG("iframe sar %d, reqseq %d, final %d, txseq %d",
7469 control->sar, control->reqseq, control->final,
7470 control->txseq);
7471
7472 /* Validate F-bit - F=0 always valid, F=1 only
7473 * valid in TX WAIT_F
7474 */
7475 if (control->final && chan->tx_state != L2CAP_TX_STATE_WAIT_F)
7476 goto drop;
7477
7478 if (chan->mode != L2CAP_MODE_STREAMING) {
7479 event = L2CAP_EV_RECV_IFRAME;
7480 err = l2cap_rx(chan, control, skb, event);
7481 } else {
7482 err = l2cap_stream_rx(chan, control, skb);
7483 }
7484
7485 if (err)
7486 l2cap_send_disconn_req(chan, ECONNRESET);
7487 } else {
7488 const u8 rx_func_to_event[4] = {
7489 L2CAP_EV_RECV_RR, L2CAP_EV_RECV_REJ,
7490 L2CAP_EV_RECV_RNR, L2CAP_EV_RECV_SREJ
7491 };
7492
7493 /* Only I-frames are expected in streaming mode */
7494 if (chan->mode == L2CAP_MODE_STREAMING)
7495 goto drop;
7496
7497 BT_DBG("sframe reqseq %d, final %d, poll %d, super %d",
7498 control->reqseq, control->final, control->poll,
7499 control->super);
7500
7501 if (len != 0) {
7502 BT_ERR("Trailing bytes: %d in sframe", len);
7503 l2cap_send_disconn_req(chan, ECONNRESET);
7504 goto drop;
7505 }
7506
7507 /* Validate F and P bits */
7508 if (control->final && (control->poll ||
7509 chan->tx_state != L2CAP_TX_STATE_WAIT_F))
7510 goto drop;
7511
7512 event = rx_func_to_event[control->super];
7513 if (l2cap_rx(chan, control, skb, event))
7514 l2cap_send_disconn_req(chan, ECONNRESET);
7515 }
7516
7517 return 0;
7518
7519drop:
7520 kfree_skb(skb);
7521 return 0;
7522}
7523
7524static void l2cap_chan_le_send_credits(struct l2cap_chan *chan)
7525{
7526 struct l2cap_conn *conn = chan->conn;
7527 struct l2cap_le_credits pkt;
7528 u16 return_credits;
7529
7530 return_credits = (chan->imtu / chan->mps) + 1;
7531
7532 if (chan->rx_credits >= return_credits)
7533 return;
7534
7535 return_credits -= chan->rx_credits;
7536
7537 BT_DBG("chan %p returning %u credits to sender", chan, return_credits);
7538
7539 chan->rx_credits += return_credits;
7540
7541 pkt.cid = cpu_to_le16(chan->scid);
7542 pkt.credits = cpu_to_le16(return_credits);
7543
7544 chan->ident = l2cap_get_ident(conn);
7545
7546 l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CREDITS, sizeof(pkt), &pkt);
7547}
7548
7549static int l2cap_ecred_recv(struct l2cap_chan *chan, struct sk_buff *skb)
7550{
7551 int err;
7552
7553 BT_DBG("SDU reassemble complete: chan %p skb->len %u", chan, skb->len);
7554
7555 /* Wait recv to confirm reception before updating the credits */
7556 err = chan->ops->recv(chan, skb);
7557
7558 /* Update credits whenever an SDU is received */
7559 l2cap_chan_le_send_credits(chan);
7560
7561 return err;
7562}
7563
7564static int l2cap_ecred_data_rcv(struct l2cap_chan *chan, struct sk_buff *skb)
7565{
7566 int err;
7567
7568 if (!chan->rx_credits) {
7569 BT_ERR("No credits to receive LE L2CAP data");
7570 l2cap_send_disconn_req(chan, ECONNRESET);
7571 return -ENOBUFS;
7572 }
7573
7574 if (chan->imtu < skb->len) {
7575 BT_ERR("Too big LE L2CAP PDU");
7576 return -ENOBUFS;
7577 }
7578
7579 chan->rx_credits--;
7580 BT_DBG("rx_credits %u -> %u", chan->rx_credits + 1, chan->rx_credits);
7581
7582 /* Update if remote had run out of credits, this should only happens
7583 * if the remote is not using the entire MPS.
7584 */
7585 if (!chan->rx_credits)
7586 l2cap_chan_le_send_credits(chan);
7587
7588 err = 0;
7589
7590 if (!chan->sdu) {
7591 u16 sdu_len;
7592
7593 sdu_len = get_unaligned_le16(skb->data);
7594 skb_pull(skb, L2CAP_SDULEN_SIZE);
7595
7596 BT_DBG("Start of new SDU. sdu_len %u skb->len %u imtu %u",
7597 sdu_len, skb->len, chan->imtu);
7598
7599 if (sdu_len > chan->imtu) {
7600 BT_ERR("Too big LE L2CAP SDU length received");
7601 err = -EMSGSIZE;
7602 goto failed;
7603 }
7604
7605 if (skb->len > sdu_len) {
7606 BT_ERR("Too much LE L2CAP data received");
7607 err = -EINVAL;
7608 goto failed;
7609 }
7610
7611 if (skb->len == sdu_len)
7612 return l2cap_ecred_recv(chan, skb);
7613
7614 chan->sdu = skb;
7615 chan->sdu_len = sdu_len;
7616 chan->sdu_last_frag = skb;
7617
7618 /* Detect if remote is not able to use the selected MPS */
7619 if (skb->len + L2CAP_SDULEN_SIZE < chan->mps) {
7620 u16 mps_len = skb->len + L2CAP_SDULEN_SIZE;
7621
7622 /* Adjust the number of credits */
7623 BT_DBG("chan->mps %u -> %u", chan->mps, mps_len);
7624 chan->mps = mps_len;
7625 l2cap_chan_le_send_credits(chan);
7626 }
7627
7628 return 0;
7629 }
7630
7631 BT_DBG("SDU fragment. chan->sdu->len %u skb->len %u chan->sdu_len %u",
7632 chan->sdu->len, skb->len, chan->sdu_len);
7633
7634 if (chan->sdu->len + skb->len > chan->sdu_len) {
7635 BT_ERR("Too much LE L2CAP data received");
7636 err = -EINVAL;
7637 goto failed;
7638 }
7639
7640 append_skb_frag(chan->sdu, skb, &chan->sdu_last_frag);
7641 skb = NULL;
7642
7643 if (chan->sdu->len == chan->sdu_len) {
7644 err = l2cap_ecred_recv(chan, chan->sdu);
7645 if (!err) {
7646 chan->sdu = NULL;
7647 chan->sdu_last_frag = NULL;
7648 chan->sdu_len = 0;
7649 }
7650 }
7651
7652failed:
7653 if (err) {
7654 kfree_skb(skb);
7655 kfree_skb(chan->sdu);
7656 chan->sdu = NULL;
7657 chan->sdu_last_frag = NULL;
7658 chan->sdu_len = 0;
7659 }
7660
7661 /* We can't return an error here since we took care of the skb
7662 * freeing internally. An error return would cause the caller to
7663 * do a double-free of the skb.
7664 */
7665 return 0;
7666}
7667
7668static void l2cap_data_channel(struct l2cap_conn *conn, u16 cid,
7669 struct sk_buff *skb)
7670{
7671 struct l2cap_chan *chan;
7672
7673 chan = l2cap_get_chan_by_scid(conn, cid);
7674 if (!chan) {
7675 if (cid == L2CAP_CID_A2MP) {
7676 chan = a2mp_channel_create(conn, skb);
7677 if (!chan) {
7678 kfree_skb(skb);
7679 return;
7680 }
7681
7682 l2cap_chan_hold(chan);
7683 l2cap_chan_lock(chan);
7684 } else {
7685 BT_DBG("unknown cid 0x%4.4x", cid);
7686 /* Drop packet and return */
7687 kfree_skb(skb);
7688 return;
7689 }
7690 }
7691
7692 BT_DBG("chan %p, len %d", chan, skb->len);
7693
7694 /* If we receive data on a fixed channel before the info req/rsp
7695 * procedure is done simply assume that the channel is supported
7696 * and mark it as ready.
7697 */
7698 if (chan->chan_type == L2CAP_CHAN_FIXED)
7699 l2cap_chan_ready(chan);
7700
7701 if (chan->state != BT_CONNECTED)
7702 goto drop;
7703
7704 switch (chan->mode) {
7705 case L2CAP_MODE_LE_FLOWCTL:
7706 case L2CAP_MODE_EXT_FLOWCTL:
7707 if (l2cap_ecred_data_rcv(chan, skb) < 0)
7708 goto drop;
7709
7710 goto done;
7711
7712 case L2CAP_MODE_BASIC:
7713 /* If socket recv buffers overflows we drop data here
7714 * which is *bad* because L2CAP has to be reliable.
7715 * But we don't have any other choice. L2CAP doesn't
7716 * provide flow control mechanism. */
7717
7718 if (chan->imtu < skb->len) {
7719 BT_ERR("Dropping L2CAP data: receive buffer overflow");
7720 goto drop;
7721 }
7722
7723 if (!chan->ops->recv(chan, skb))
7724 goto done;
7725 break;
7726
7727 case L2CAP_MODE_ERTM:
7728 case L2CAP_MODE_STREAMING:
7729 l2cap_data_rcv(chan, skb);
7730 goto done;
7731
7732 default:
7733 BT_DBG("chan %p: bad mode 0x%2.2x", chan, chan->mode);
7734 break;
7735 }
7736
7737drop:
7738 kfree_skb(skb);
7739
7740done:
7741 l2cap_chan_unlock(chan);
7742 l2cap_chan_put(chan);
7743}
7744
7745static void l2cap_conless_channel(struct l2cap_conn *conn, __le16 psm,
7746 struct sk_buff *skb)
7747{
7748 struct hci_conn *hcon = conn->hcon;
7749 struct l2cap_chan *chan;
7750
7751 if (hcon->type != ACL_LINK)
7752 goto free_skb;
7753
7754 chan = l2cap_global_chan_by_psm(0, psm, &hcon->src, &hcon->dst,
7755 ACL_LINK);
7756 if (!chan)
7757 goto free_skb;
7758
7759 BT_DBG("chan %p, len %d", chan, skb->len);
7760
7761 if (chan->state != BT_BOUND && chan->state != BT_CONNECTED)
7762 goto drop;
7763
7764 if (chan->imtu < skb->len)
7765 goto drop;
7766
7767 /* Store remote BD_ADDR and PSM for msg_name */
7768 bacpy(&bt_cb(skb)->l2cap.bdaddr, &hcon->dst);
7769 bt_cb(skb)->l2cap.psm = psm;
7770
7771 if (!chan->ops->recv(chan, skb)) {
7772 l2cap_chan_put(chan);
7773 return;
7774 }
7775
7776drop:
7777 l2cap_chan_put(chan);
7778free_skb:
7779 kfree_skb(skb);
7780}
7781
7782static void l2cap_recv_frame(struct l2cap_conn *conn, struct sk_buff *skb)
7783{
7784 struct l2cap_hdr *lh = (void *) skb->data;
7785 struct hci_conn *hcon = conn->hcon;
7786 u16 cid, len;
7787 __le16 psm;
7788
7789 if (hcon->state != BT_CONNECTED) {
7790 BT_DBG("queueing pending rx skb");
7791 skb_queue_tail(&conn->pending_rx, skb);
7792 return;
7793 }
7794
7795 skb_pull(skb, L2CAP_HDR_SIZE);
7796 cid = __le16_to_cpu(lh->cid);
7797 len = __le16_to_cpu(lh->len);
7798
7799 if (len != skb->len) {
7800 kfree_skb(skb);
7801 return;
7802 }
7803
7804 /* Since we can't actively block incoming LE connections we must
7805 * at least ensure that we ignore incoming data from them.
7806 */
7807 if (hcon->type == LE_LINK &&
7808 hci_bdaddr_list_lookup(&hcon->hdev->reject_list, &hcon->dst,
7809 bdaddr_dst_type(hcon))) {
7810 kfree_skb(skb);
7811 return;
7812 }
7813
7814 BT_DBG("len %d, cid 0x%4.4x", len, cid);
7815
7816 switch (cid) {
7817 case L2CAP_CID_SIGNALING:
7818 l2cap_sig_channel(conn, skb);
7819 break;
7820
7821 case L2CAP_CID_CONN_LESS:
7822 psm = get_unaligned((__le16 *) skb->data);
7823 skb_pull(skb, L2CAP_PSMLEN_SIZE);
7824 l2cap_conless_channel(conn, psm, skb);
7825 break;
7826
7827 case L2CAP_CID_LE_SIGNALING:
7828 l2cap_le_sig_channel(conn, skb);
7829 break;
7830
7831 default:
7832 l2cap_data_channel(conn, cid, skb);
7833 break;
7834 }
7835}
7836
7837static void process_pending_rx(struct work_struct *work)
7838{
7839 struct l2cap_conn *conn = container_of(work, struct l2cap_conn,
7840 pending_rx_work);
7841 struct sk_buff *skb;
7842
7843 BT_DBG("");
7844
7845 while ((skb = skb_dequeue(&conn->pending_rx)))
7846 l2cap_recv_frame(conn, skb);
7847}
7848
7849static struct l2cap_conn *l2cap_conn_add(struct hci_conn *hcon)
7850{
7851 struct l2cap_conn *conn = hcon->l2cap_data;
7852 struct hci_chan *hchan;
7853
7854 if (conn)
7855 return conn;
7856
7857 hchan = hci_chan_create(hcon);
7858 if (!hchan)
7859 return NULL;
7860
7861 conn = kzalloc(sizeof(*conn), GFP_KERNEL);
7862 if (!conn) {
7863 hci_chan_del(hchan);
7864 return NULL;
7865 }
7866
7867 kref_init(&conn->ref);
7868 hcon->l2cap_data = conn;
7869 conn->hcon = hci_conn_get(hcon);
7870 conn->hchan = hchan;
7871
7872 BT_DBG("hcon %p conn %p hchan %p", hcon, conn, hchan);
7873
7874 switch (hcon->type) {
7875 case LE_LINK:
7876 if (hcon->hdev->le_mtu) {
7877 conn->mtu = hcon->hdev->le_mtu;
7878 break;
7879 }
7880 fallthrough;
7881 default:
7882 conn->mtu = hcon->hdev->acl_mtu;
7883 break;
7884 }
7885
7886 conn->feat_mask = 0;
7887
7888 conn->local_fixed_chan = L2CAP_FC_SIG_BREDR | L2CAP_FC_CONNLESS;
7889
7890 if (hcon->type == ACL_LINK &&
7891 hci_dev_test_flag(hcon->hdev, HCI_HS_ENABLED))
7892 conn->local_fixed_chan |= L2CAP_FC_A2MP;
7893
7894 if (hci_dev_test_flag(hcon->hdev, HCI_LE_ENABLED) &&
7895 (bredr_sc_enabled(hcon->hdev) ||
7896 hci_dev_test_flag(hcon->hdev, HCI_FORCE_BREDR_SMP)))
7897 conn->local_fixed_chan |= L2CAP_FC_SMP_BREDR;
7898
7899 mutex_init(&conn->ident_lock);
7900 mutex_init(&conn->chan_lock);
7901
7902 INIT_LIST_HEAD(&conn->chan_l);
7903 INIT_LIST_HEAD(&conn->users);
7904
7905 INIT_DELAYED_WORK(&conn->info_timer, l2cap_info_timeout);
7906
7907 skb_queue_head_init(&conn->pending_rx);
7908 INIT_WORK(&conn->pending_rx_work, process_pending_rx);
7909 INIT_DELAYED_WORK(&conn->id_addr_timer, l2cap_conn_update_id_addr);
7910
7911 conn->disc_reason = HCI_ERROR_REMOTE_USER_TERM;
7912
7913 return conn;
7914}
7915
7916static bool is_valid_psm(u16 psm, u8 dst_type)
7917{
7918 if (!psm)
7919 return false;
7920
7921 if (bdaddr_type_is_le(dst_type))
7922 return (psm <= 0x00ff);
7923
7924 /* PSM must be odd and lsb of upper byte must be 0 */
7925 return ((psm & 0x0101) == 0x0001);
7926}
7927
7928struct l2cap_chan_data {
7929 struct l2cap_chan *chan;
7930 struct pid *pid;
7931 int count;
7932};
7933
7934static void l2cap_chan_by_pid(struct l2cap_chan *chan, void *data)
7935{
7936 struct l2cap_chan_data *d = data;
7937 struct pid *pid;
7938
7939 if (chan == d->chan)
7940 return;
7941
7942 if (!test_bit(FLAG_DEFER_SETUP, &chan->flags))
7943 return;
7944
7945 pid = chan->ops->get_peer_pid(chan);
7946
7947 /* Only count deferred channels with the same PID/PSM */
7948 if (d->pid != pid || chan->psm != d->chan->psm || chan->ident ||
7949 chan->mode != L2CAP_MODE_EXT_FLOWCTL || chan->state != BT_CONNECT)
7950 return;
7951
7952 d->count++;
7953}
7954
7955int l2cap_chan_connect(struct l2cap_chan *chan, __le16 psm, u16 cid,
7956 bdaddr_t *dst, u8 dst_type)
7957{
7958 struct l2cap_conn *conn;
7959 struct hci_conn *hcon;
7960 struct hci_dev *hdev;
7961 int err;
7962
7963 BT_DBG("%pMR -> %pMR (type %u) psm 0x%4.4x mode 0x%2.2x", &chan->src,
7964 dst, dst_type, __le16_to_cpu(psm), chan->mode);
7965
7966 hdev = hci_get_route(dst, &chan->src, chan->src_type);
7967 if (!hdev)
7968 return -EHOSTUNREACH;
7969
7970 hci_dev_lock(hdev);
7971
7972 if (!is_valid_psm(__le16_to_cpu(psm), dst_type) && !cid &&
7973 chan->chan_type != L2CAP_CHAN_RAW) {
7974 err = -EINVAL;
7975 goto done;
7976 }
7977
7978 if (chan->chan_type == L2CAP_CHAN_CONN_ORIENTED && !psm) {
7979 err = -EINVAL;
7980 goto done;
7981 }
7982
7983 if (chan->chan_type == L2CAP_CHAN_FIXED && !cid) {
7984 err = -EINVAL;
7985 goto done;
7986 }
7987
7988 switch (chan->mode) {
7989 case L2CAP_MODE_BASIC:
7990 break;
7991 case L2CAP_MODE_LE_FLOWCTL:
7992 break;
7993 case L2CAP_MODE_EXT_FLOWCTL:
7994 if (!enable_ecred) {
7995 err = -EOPNOTSUPP;
7996 goto done;
7997 }
7998 break;
7999 case L2CAP_MODE_ERTM:
8000 case L2CAP_MODE_STREAMING:
8001 if (!disable_ertm)
8002 break;
8003 fallthrough;
8004 default:
8005 err = -EOPNOTSUPP;
8006 goto done;
8007 }
8008
8009 switch (chan->state) {
8010 case BT_CONNECT:
8011 case BT_CONNECT2:
8012 case BT_CONFIG:
8013 /* Already connecting */
8014 err = 0;
8015 goto done;
8016
8017 case BT_CONNECTED:
8018 /* Already connected */
8019 err = -EISCONN;
8020 goto done;
8021
8022 case BT_OPEN:
8023 case BT_BOUND:
8024 /* Can connect */
8025 break;
8026
8027 default:
8028 err = -EBADFD;
8029 goto done;
8030 }
8031
8032 /* Set destination address and psm */
8033 bacpy(&chan->dst, dst);
8034 chan->dst_type = dst_type;
8035
8036 chan->psm = psm;
8037 chan->dcid = cid;
8038
8039 if (bdaddr_type_is_le(dst_type)) {
8040 /* Convert from L2CAP channel address type to HCI address type
8041 */
8042 if (dst_type == BDADDR_LE_PUBLIC)
8043 dst_type = ADDR_LE_DEV_PUBLIC;
8044 else
8045 dst_type = ADDR_LE_DEV_RANDOM;
8046
8047 if (hci_dev_test_flag(hdev, HCI_ADVERTISING))
8048 hcon = hci_connect_le(hdev, dst, dst_type, false,
8049 chan->sec_level,
8050 HCI_LE_CONN_TIMEOUT,
8051 HCI_ROLE_SLAVE);
8052 else
8053 hcon = hci_connect_le_scan(hdev, dst, dst_type,
8054 chan->sec_level,
8055 HCI_LE_CONN_TIMEOUT,
8056 CONN_REASON_L2CAP_CHAN);
8057
8058 } else {
8059 u8 auth_type = l2cap_get_auth_type(chan);
8060 hcon = hci_connect_acl(hdev, dst, chan->sec_level, auth_type,
8061 CONN_REASON_L2CAP_CHAN);
8062 }
8063
8064 if (IS_ERR(hcon)) {
8065 err = PTR_ERR(hcon);
8066 goto done;
8067 }
8068
8069 conn = l2cap_conn_add(hcon);
8070 if (!conn) {
8071 hci_conn_drop(hcon);
8072 err = -ENOMEM;
8073 goto done;
8074 }
8075
8076 if (chan->mode == L2CAP_MODE_EXT_FLOWCTL) {
8077 struct l2cap_chan_data data;
8078
8079 data.chan = chan;
8080 data.pid = chan->ops->get_peer_pid(chan);
8081 data.count = 1;
8082
8083 l2cap_chan_list(conn, l2cap_chan_by_pid, &data);
8084
8085 /* Check if there isn't too many channels being connected */
8086 if (data.count > L2CAP_ECRED_CONN_SCID_MAX) {
8087 hci_conn_drop(hcon);
8088 err = -EPROTO;
8089 goto done;
8090 }
8091 }
8092
8093 mutex_lock(&conn->chan_lock);
8094 l2cap_chan_lock(chan);
8095
8096 if (cid && __l2cap_get_chan_by_dcid(conn, cid)) {
8097 hci_conn_drop(hcon);
8098 err = -EBUSY;
8099 goto chan_unlock;
8100 }
8101
8102 /* Update source addr of the socket */
8103 bacpy(&chan->src, &hcon->src);
8104 chan->src_type = bdaddr_src_type(hcon);
8105
8106 __l2cap_chan_add(conn, chan);
8107
8108 /* l2cap_chan_add takes its own ref so we can drop this one */
8109 hci_conn_drop(hcon);
8110
8111 l2cap_state_change(chan, BT_CONNECT);
8112 __set_chan_timer(chan, chan->ops->get_sndtimeo(chan));
8113
8114 /* Release chan->sport so that it can be reused by other
8115 * sockets (as it's only used for listening sockets).
8116 */
8117 write_lock(&chan_list_lock);
8118 chan->sport = 0;
8119 write_unlock(&chan_list_lock);
8120
8121 if (hcon->state == BT_CONNECTED) {
8122 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) {
8123 __clear_chan_timer(chan);
8124 if (l2cap_chan_check_security(chan, true))
8125 l2cap_state_change(chan, BT_CONNECTED);
8126 } else
8127 l2cap_do_start(chan);
8128 }
8129
8130 err = 0;
8131
8132chan_unlock:
8133 l2cap_chan_unlock(chan);
8134 mutex_unlock(&conn->chan_lock);
8135done:
8136 hci_dev_unlock(hdev);
8137 hci_dev_put(hdev);
8138 return err;
8139}
8140EXPORT_SYMBOL_GPL(l2cap_chan_connect);
8141
8142static void l2cap_ecred_reconfigure(struct l2cap_chan *chan)
8143{
8144 struct l2cap_conn *conn = chan->conn;
8145 struct {
8146 struct l2cap_ecred_reconf_req req;
8147 __le16 scid;
8148 } pdu;
8149
8150 pdu.req.mtu = cpu_to_le16(chan->imtu);
8151 pdu.req.mps = cpu_to_le16(chan->mps);
8152 pdu.scid = cpu_to_le16(chan->scid);
8153
8154 chan->ident = l2cap_get_ident(conn);
8155
8156 l2cap_send_cmd(conn, chan->ident, L2CAP_ECRED_RECONF_REQ,
8157 sizeof(pdu), &pdu);
8158}
8159
8160int l2cap_chan_reconfigure(struct l2cap_chan *chan, __u16 mtu)
8161{
8162 if (chan->imtu > mtu)
8163 return -EINVAL;
8164
8165 BT_DBG("chan %p mtu 0x%4.4x", chan, mtu);
8166
8167 chan->imtu = mtu;
8168
8169 l2cap_ecred_reconfigure(chan);
8170
8171 return 0;
8172}
8173
8174/* ---- L2CAP interface with lower layer (HCI) ---- */
8175
8176int l2cap_connect_ind(struct hci_dev *hdev, bdaddr_t *bdaddr)
8177{
8178 int exact = 0, lm1 = 0, lm2 = 0;
8179 struct l2cap_chan *c;
8180
8181 BT_DBG("hdev %s, bdaddr %pMR", hdev->name, bdaddr);
8182
8183 /* Find listening sockets and check their link_mode */
8184 read_lock(&chan_list_lock);
8185 list_for_each_entry(c, &chan_list, global_l) {
8186 if (c->state != BT_LISTEN)
8187 continue;
8188
8189 if (!bacmp(&c->src, &hdev->bdaddr)) {
8190 lm1 |= HCI_LM_ACCEPT;
8191 if (test_bit(FLAG_ROLE_SWITCH, &c->flags))
8192 lm1 |= HCI_LM_MASTER;
8193 exact++;
8194 } else if (!bacmp(&c->src, BDADDR_ANY)) {
8195 lm2 |= HCI_LM_ACCEPT;
8196 if (test_bit(FLAG_ROLE_SWITCH, &c->flags))
8197 lm2 |= HCI_LM_MASTER;
8198 }
8199 }
8200 read_unlock(&chan_list_lock);
8201
8202 return exact ? lm1 : lm2;
8203}
8204
8205/* Find the next fixed channel in BT_LISTEN state, continue iteration
8206 * from an existing channel in the list or from the beginning of the
8207 * global list (by passing NULL as first parameter).
8208 */
8209static struct l2cap_chan *l2cap_global_fixed_chan(struct l2cap_chan *c,
8210 struct hci_conn *hcon)
8211{
8212 u8 src_type = bdaddr_src_type(hcon);
8213
8214 read_lock(&chan_list_lock);
8215
8216 if (c)
8217 c = list_next_entry(c, global_l);
8218 else
8219 c = list_entry(chan_list.next, typeof(*c), global_l);
8220
8221 list_for_each_entry_from(c, &chan_list, global_l) {
8222 if (c->chan_type != L2CAP_CHAN_FIXED)
8223 continue;
8224 if (c->state != BT_LISTEN)
8225 continue;
8226 if (bacmp(&c->src, &hcon->src) && bacmp(&c->src, BDADDR_ANY))
8227 continue;
8228 if (src_type != c->src_type)
8229 continue;
8230
8231 c = l2cap_chan_hold_unless_zero(c);
8232 read_unlock(&chan_list_lock);
8233 return c;
8234 }
8235
8236 read_unlock(&chan_list_lock);
8237
8238 return NULL;
8239}
8240
8241static void l2cap_connect_cfm(struct hci_conn *hcon, u8 status)
8242{
8243 struct hci_dev *hdev = hcon->hdev;
8244 struct l2cap_conn *conn;
8245 struct l2cap_chan *pchan;
8246 u8 dst_type;
8247
8248 if (hcon->type != ACL_LINK && hcon->type != LE_LINK)
8249 return;
8250
8251 BT_DBG("hcon %p bdaddr %pMR status %d", hcon, &hcon->dst, status);
8252
8253 if (status) {
8254 l2cap_conn_del(hcon, bt_to_errno(status));
8255 return;
8256 }
8257
8258 conn = l2cap_conn_add(hcon);
8259 if (!conn)
8260 return;
8261
8262 dst_type = bdaddr_dst_type(hcon);
8263
8264 /* If device is blocked, do not create channels for it */
8265 if (hci_bdaddr_list_lookup(&hdev->reject_list, &hcon->dst, dst_type))
8266 return;
8267
8268 /* Find fixed channels and notify them of the new connection. We
8269 * use multiple individual lookups, continuing each time where
8270 * we left off, because the list lock would prevent calling the
8271 * potentially sleeping l2cap_chan_lock() function.
8272 */
8273 pchan = l2cap_global_fixed_chan(NULL, hcon);
8274 while (pchan) {
8275 struct l2cap_chan *chan, *next;
8276
8277 /* Client fixed channels should override server ones */
8278 if (__l2cap_get_chan_by_dcid(conn, pchan->scid))
8279 goto next;
8280
8281 l2cap_chan_lock(pchan);
8282 chan = pchan->ops->new_connection(pchan);
8283 if (chan) {
8284 bacpy(&chan->src, &hcon->src);
8285 bacpy(&chan->dst, &hcon->dst);
8286 chan->src_type = bdaddr_src_type(hcon);
8287 chan->dst_type = dst_type;
8288
8289 __l2cap_chan_add(conn, chan);
8290 }
8291
8292 l2cap_chan_unlock(pchan);
8293next:
8294 next = l2cap_global_fixed_chan(pchan, hcon);
8295 l2cap_chan_put(pchan);
8296 pchan = next;
8297 }
8298
8299 l2cap_conn_ready(conn);
8300}
8301
8302int l2cap_disconn_ind(struct hci_conn *hcon)
8303{
8304 struct l2cap_conn *conn = hcon->l2cap_data;
8305
8306 BT_DBG("hcon %p", hcon);
8307
8308 if (!conn)
8309 return HCI_ERROR_REMOTE_USER_TERM;
8310 return conn->disc_reason;
8311}
8312
8313static void l2cap_disconn_cfm(struct hci_conn *hcon, u8 reason)
8314{
8315 if (hcon->type != ACL_LINK && hcon->type != LE_LINK)
8316 return;
8317
8318 BT_DBG("hcon %p reason %d", hcon, reason);
8319
8320 l2cap_conn_del(hcon, bt_to_errno(reason));
8321}
8322
8323static inline void l2cap_check_encryption(struct l2cap_chan *chan, u8 encrypt)
8324{
8325 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED)
8326 return;
8327
8328 if (encrypt == 0x00) {
8329 if (chan->sec_level == BT_SECURITY_MEDIUM) {
8330 __set_chan_timer(chan, L2CAP_ENC_TIMEOUT);
8331 } else if (chan->sec_level == BT_SECURITY_HIGH ||
8332 chan->sec_level == BT_SECURITY_FIPS)
8333 l2cap_chan_close(chan, ECONNREFUSED);
8334 } else {
8335 if (chan->sec_level == BT_SECURITY_MEDIUM)
8336 __clear_chan_timer(chan);
8337 }
8338}
8339
8340static void l2cap_security_cfm(struct hci_conn *hcon, u8 status, u8 encrypt)
8341{
8342 struct l2cap_conn *conn = hcon->l2cap_data;
8343 struct l2cap_chan *chan;
8344
8345 if (!conn)
8346 return;
8347
8348 BT_DBG("conn %p status 0x%2.2x encrypt %u", conn, status, encrypt);
8349
8350 mutex_lock(&conn->chan_lock);
8351
8352 list_for_each_entry(chan, &conn->chan_l, list) {
8353 l2cap_chan_lock(chan);
8354
8355 BT_DBG("chan %p scid 0x%4.4x state %s", chan, chan->scid,
8356 state_to_string(chan->state));
8357
8358 if (chan->scid == L2CAP_CID_A2MP) {
8359 l2cap_chan_unlock(chan);
8360 continue;
8361 }
8362
8363 if (!status && encrypt)
8364 chan->sec_level = hcon->sec_level;
8365
8366 if (!__l2cap_no_conn_pending(chan)) {
8367 l2cap_chan_unlock(chan);
8368 continue;
8369 }
8370
8371 if (!status && (chan->state == BT_CONNECTED ||
8372 chan->state == BT_CONFIG)) {
8373 chan->ops->resume(chan);
8374 l2cap_check_encryption(chan, encrypt);
8375 l2cap_chan_unlock(chan);
8376 continue;
8377 }
8378
8379 if (chan->state == BT_CONNECT) {
8380 if (!status && l2cap_check_enc_key_size(hcon))
8381 l2cap_start_connection(chan);
8382 else
8383 __set_chan_timer(chan, L2CAP_DISC_TIMEOUT);
8384 } else if (chan->state == BT_CONNECT2 &&
8385 !(chan->mode == L2CAP_MODE_EXT_FLOWCTL ||
8386 chan->mode == L2CAP_MODE_LE_FLOWCTL)) {
8387 struct l2cap_conn_rsp rsp;
8388 __u16 res, stat;
8389
8390 if (!status && l2cap_check_enc_key_size(hcon)) {
8391 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) {
8392 res = L2CAP_CR_PEND;
8393 stat = L2CAP_CS_AUTHOR_PEND;
8394 chan->ops->defer(chan);
8395 } else {
8396 l2cap_state_change(chan, BT_CONFIG);
8397 res = L2CAP_CR_SUCCESS;
8398 stat = L2CAP_CS_NO_INFO;
8399 }
8400 } else {
8401 l2cap_state_change(chan, BT_DISCONN);
8402 __set_chan_timer(chan, L2CAP_DISC_TIMEOUT);
8403 res = L2CAP_CR_SEC_BLOCK;
8404 stat = L2CAP_CS_NO_INFO;
8405 }
8406
8407 rsp.scid = cpu_to_le16(chan->dcid);
8408 rsp.dcid = cpu_to_le16(chan->scid);
8409 rsp.result = cpu_to_le16(res);
8410 rsp.status = cpu_to_le16(stat);
8411 l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_RSP,
8412 sizeof(rsp), &rsp);
8413
8414 if (!test_bit(CONF_REQ_SENT, &chan->conf_state) &&
8415 res == L2CAP_CR_SUCCESS) {
8416 char buf[128];
8417 set_bit(CONF_REQ_SENT, &chan->conf_state);
8418 l2cap_send_cmd(conn, l2cap_get_ident(conn),
8419 L2CAP_CONF_REQ,
8420 l2cap_build_conf_req(chan, buf, sizeof(buf)),
8421 buf);
8422 chan->num_conf_req++;
8423 }
8424 }
8425
8426 l2cap_chan_unlock(chan);
8427 }
8428
8429 mutex_unlock(&conn->chan_lock);
8430}
8431
8432/* Append fragment into frame respecting the maximum len of rx_skb */
8433static int l2cap_recv_frag(struct l2cap_conn *conn, struct sk_buff *skb,
8434 u16 len)
8435{
8436 if (!conn->rx_skb) {
8437 /* Allocate skb for the complete frame (with header) */
8438 conn->rx_skb = bt_skb_alloc(len, GFP_KERNEL);
8439 if (!conn->rx_skb)
8440 return -ENOMEM;
8441 /* Init rx_len */
8442 conn->rx_len = len;
8443 }
8444
8445 /* Copy as much as the rx_skb can hold */
8446 len = min_t(u16, len, skb->len);
8447 skb_copy_from_linear_data(skb, skb_put(conn->rx_skb, len), len);
8448 skb_pull(skb, len);
8449 conn->rx_len -= len;
8450
8451 return len;
8452}
8453
8454static int l2cap_recv_len(struct l2cap_conn *conn, struct sk_buff *skb)
8455{
8456 struct sk_buff *rx_skb;
8457 int len;
8458
8459 /* Append just enough to complete the header */
8460 len = l2cap_recv_frag(conn, skb, L2CAP_LEN_SIZE - conn->rx_skb->len);
8461
8462 /* If header could not be read just continue */
8463 if (len < 0 || conn->rx_skb->len < L2CAP_LEN_SIZE)
8464 return len;
8465
8466 rx_skb = conn->rx_skb;
8467 len = get_unaligned_le16(rx_skb->data);
8468
8469 /* Check if rx_skb has enough space to received all fragments */
8470 if (len + (L2CAP_HDR_SIZE - L2CAP_LEN_SIZE) <= skb_tailroom(rx_skb)) {
8471 /* Update expected len */
8472 conn->rx_len = len + (L2CAP_HDR_SIZE - L2CAP_LEN_SIZE);
8473 return L2CAP_LEN_SIZE;
8474 }
8475
8476 /* Reset conn->rx_skb since it will need to be reallocated in order to
8477 * fit all fragments.
8478 */
8479 conn->rx_skb = NULL;
8480
8481 /* Reallocates rx_skb using the exact expected length */
8482 len = l2cap_recv_frag(conn, rx_skb,
8483 len + (L2CAP_HDR_SIZE - L2CAP_LEN_SIZE));
8484 kfree_skb(rx_skb);
8485
8486 return len;
8487}
8488
8489static void l2cap_recv_reset(struct l2cap_conn *conn)
8490{
8491 kfree_skb(conn->rx_skb);
8492 conn->rx_skb = NULL;
8493 conn->rx_len = 0;
8494}
8495
8496void l2cap_recv_acldata(struct hci_conn *hcon, struct sk_buff *skb, u16 flags)
8497{
8498 struct l2cap_conn *conn = hcon->l2cap_data;
8499 int len;
8500
8501 /* For AMP controller do not create l2cap conn */
8502 if (!conn && hcon->hdev->dev_type != HCI_PRIMARY)
8503 goto drop;
8504
8505 if (!conn)
8506 conn = l2cap_conn_add(hcon);
8507
8508 if (!conn)
8509 goto drop;
8510
8511 BT_DBG("conn %p len %u flags 0x%x", conn, skb->len, flags);
8512
8513 switch (flags) {
8514 case ACL_START:
8515 case ACL_START_NO_FLUSH:
8516 case ACL_COMPLETE:
8517 if (conn->rx_skb) {
8518 BT_ERR("Unexpected start frame (len %d)", skb->len);
8519 l2cap_recv_reset(conn);
8520 l2cap_conn_unreliable(conn, ECOMM);
8521 }
8522
8523 /* Start fragment may not contain the L2CAP length so just
8524 * copy the initial byte when that happens and use conn->mtu as
8525 * expected length.
8526 */
8527 if (skb->len < L2CAP_LEN_SIZE) {
8528 l2cap_recv_frag(conn, skb, conn->mtu);
8529 break;
8530 }
8531
8532 len = get_unaligned_le16(skb->data) + L2CAP_HDR_SIZE;
8533
8534 if (len == skb->len) {
8535 /* Complete frame received */
8536 l2cap_recv_frame(conn, skb);
8537 return;
8538 }
8539
8540 BT_DBG("Start: total len %d, frag len %u", len, skb->len);
8541
8542 if (skb->len > len) {
8543 BT_ERR("Frame is too long (len %u, expected len %d)",
8544 skb->len, len);
8545 l2cap_conn_unreliable(conn, ECOMM);
8546 goto drop;
8547 }
8548
8549 /* Append fragment into frame (with header) */
8550 if (l2cap_recv_frag(conn, skb, len) < 0)
8551 goto drop;
8552
8553 break;
8554
8555 case ACL_CONT:
8556 BT_DBG("Cont: frag len %u (expecting %u)", skb->len, conn->rx_len);
8557
8558 if (!conn->rx_skb) {
8559 BT_ERR("Unexpected continuation frame (len %d)", skb->len);
8560 l2cap_conn_unreliable(conn, ECOMM);
8561 goto drop;
8562 }
8563
8564 /* Complete the L2CAP length if it has not been read */
8565 if (conn->rx_skb->len < L2CAP_LEN_SIZE) {
8566 if (l2cap_recv_len(conn, skb) < 0) {
8567 l2cap_conn_unreliable(conn, ECOMM);
8568 goto drop;
8569 }
8570
8571 /* Header still could not be read just continue */
8572 if (conn->rx_skb->len < L2CAP_LEN_SIZE)
8573 break;
8574 }
8575
8576 if (skb->len > conn->rx_len) {
8577 BT_ERR("Fragment is too long (len %u, expected %u)",
8578 skb->len, conn->rx_len);
8579 l2cap_recv_reset(conn);
8580 l2cap_conn_unreliable(conn, ECOMM);
8581 goto drop;
8582 }
8583
8584 /* Append fragment into frame (with header) */
8585 l2cap_recv_frag(conn, skb, skb->len);
8586
8587 if (!conn->rx_len) {
8588 /* Complete frame received. l2cap_recv_frame
8589 * takes ownership of the skb so set the global
8590 * rx_skb pointer to NULL first.
8591 */
8592 struct sk_buff *rx_skb = conn->rx_skb;
8593 conn->rx_skb = NULL;
8594 l2cap_recv_frame(conn, rx_skb);
8595 }
8596 break;
8597 }
8598
8599drop:
8600 kfree_skb(skb);
8601}
8602
8603static struct hci_cb l2cap_cb = {
8604 .name = "L2CAP",
8605 .connect_cfm = l2cap_connect_cfm,
8606 .disconn_cfm = l2cap_disconn_cfm,
8607 .security_cfm = l2cap_security_cfm,
8608};
8609
8610static int l2cap_debugfs_show(struct seq_file *f, void *p)
8611{
8612 struct l2cap_chan *c;
8613
8614 read_lock(&chan_list_lock);
8615
8616 list_for_each_entry(c, &chan_list, global_l) {
8617 seq_printf(f, "%pMR (%u) %pMR (%u) %d %d 0x%4.4x 0x%4.4x %d %d %d %d\n",
8618 &c->src, c->src_type, &c->dst, c->dst_type,
8619 c->state, __le16_to_cpu(c->psm),
8620 c->scid, c->dcid, c->imtu, c->omtu,
8621 c->sec_level, c->mode);
8622 }
8623
8624 read_unlock(&chan_list_lock);
8625
8626 return 0;
8627}
8628
8629DEFINE_SHOW_ATTRIBUTE(l2cap_debugfs);
8630
8631static struct dentry *l2cap_debugfs;
8632
8633int __init l2cap_init(void)
8634{
8635 int err;
8636
8637 err = l2cap_init_sockets();
8638 if (err < 0)
8639 return err;
8640
8641 hci_register_cb(&l2cap_cb);
8642
8643 if (IS_ERR_OR_NULL(bt_debugfs))
8644 return 0;
8645
8646 l2cap_debugfs = debugfs_create_file("l2cap", 0444, bt_debugfs,
8647 NULL, &l2cap_debugfs_fops);
8648
8649 return 0;
8650}
8651
8652void l2cap_exit(void)
8653{
8654 debugfs_remove(l2cap_debugfs);
8655 hci_unregister_cb(&l2cap_cb);
8656 l2cap_cleanup_sockets();
8657}
8658
8659module_param(disable_ertm, bool, 0644);
8660MODULE_PARM_DESC(disable_ertm, "Disable enhanced retransmission mode");
8661
8662module_param(enable_ecred, bool, 0644);
8663MODULE_PARM_DESC(enable_ecred, "Enable enhanced credit flow control mode");