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