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[mirror_ubuntu-zesty-kernel.git] / net / bluetooth / l2cap_core.c
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
47 bool disable_ertm;
48
49 static u32 l2cap_feat_mask = L2CAP_FEAT_FIXED_CHAN | L2CAP_FEAT_UCD;
50
51 static LIST_HEAD(chan_list);
52 static DEFINE_RWLOCK(chan_list_lock);
53
54 static u16 le_max_credits = L2CAP_LE_MAX_CREDITS;
55 static u16 le_default_mps = L2CAP_LE_DEFAULT_MPS;
56
57 static struct sk_buff *l2cap_build_cmd(struct l2cap_conn *conn,
58 u8 code, u8 ident, u16 dlen, void *data);
59 static void l2cap_send_cmd(struct l2cap_conn *conn, u8 ident, u8 code, u16 len,
60 void *data);
61 static int l2cap_build_conf_req(struct l2cap_chan *chan, void *data);
62 static void l2cap_send_disconn_req(struct l2cap_chan *chan, int err);
63
64 static void l2cap_tx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
65 struct sk_buff_head *skbs, u8 event);
66
67 static inline u8 bdaddr_type(u8 link_type, u8 bdaddr_type)
68 {
69 if (link_type == LE_LINK) {
70 if (bdaddr_type == ADDR_LE_DEV_PUBLIC)
71 return BDADDR_LE_PUBLIC;
72 else
73 return BDADDR_LE_RANDOM;
74 }
75
76 return BDADDR_BREDR;
77 }
78
79 static inline u8 bdaddr_src_type(struct hci_conn *hcon)
80 {
81 return bdaddr_type(hcon->type, hcon->src_type);
82 }
83
84 static inline u8 bdaddr_dst_type(struct hci_conn *hcon)
85 {
86 return bdaddr_type(hcon->type, hcon->dst_type);
87 }
88
89 /* ---- L2CAP channels ---- */
90
91 static struct l2cap_chan *__l2cap_get_chan_by_dcid(struct l2cap_conn *conn,
92 u16 cid)
93 {
94 struct l2cap_chan *c;
95
96 list_for_each_entry(c, &conn->chan_l, list) {
97 if (c->dcid == cid)
98 return c;
99 }
100 return NULL;
101 }
102
103 static struct l2cap_chan *__l2cap_get_chan_by_scid(struct l2cap_conn *conn,
104 u16 cid)
105 {
106 struct l2cap_chan *c;
107
108 list_for_each_entry(c, &conn->chan_l, list) {
109 if (c->scid == cid)
110 return c;
111 }
112 return NULL;
113 }
114
115 /* Find channel with given SCID.
116 * Returns locked channel. */
117 static struct l2cap_chan *l2cap_get_chan_by_scid(struct l2cap_conn *conn,
118 u16 cid)
119 {
120 struct l2cap_chan *c;
121
122 mutex_lock(&conn->chan_lock);
123 c = __l2cap_get_chan_by_scid(conn, cid);
124 if (c)
125 l2cap_chan_lock(c);
126 mutex_unlock(&conn->chan_lock);
127
128 return c;
129 }
130
131 /* Find channel with given DCID.
132 * Returns locked channel.
133 */
134 static struct l2cap_chan *l2cap_get_chan_by_dcid(struct l2cap_conn *conn,
135 u16 cid)
136 {
137 struct l2cap_chan *c;
138
139 mutex_lock(&conn->chan_lock);
140 c = __l2cap_get_chan_by_dcid(conn, cid);
141 if (c)
142 l2cap_chan_lock(c);
143 mutex_unlock(&conn->chan_lock);
144
145 return c;
146 }
147
148 static struct l2cap_chan *__l2cap_get_chan_by_ident(struct l2cap_conn *conn,
149 u8 ident)
150 {
151 struct l2cap_chan *c;
152
153 list_for_each_entry(c, &conn->chan_l, list) {
154 if (c->ident == ident)
155 return c;
156 }
157 return NULL;
158 }
159
160 static struct l2cap_chan *l2cap_get_chan_by_ident(struct l2cap_conn *conn,
161 u8 ident)
162 {
163 struct l2cap_chan *c;
164
165 mutex_lock(&conn->chan_lock);
166 c = __l2cap_get_chan_by_ident(conn, ident);
167 if (c)
168 l2cap_chan_lock(c);
169 mutex_unlock(&conn->chan_lock);
170
171 return c;
172 }
173
174 static struct l2cap_chan *__l2cap_global_chan_by_addr(__le16 psm, bdaddr_t *src)
175 {
176 struct l2cap_chan *c;
177
178 list_for_each_entry(c, &chan_list, global_l) {
179 if (c->sport == psm && !bacmp(&c->src, src))
180 return c;
181 }
182 return NULL;
183 }
184
185 int l2cap_add_psm(struct l2cap_chan *chan, bdaddr_t *src, __le16 psm)
186 {
187 int err;
188
189 write_lock(&chan_list_lock);
190
191 if (psm && __l2cap_global_chan_by_addr(psm, src)) {
192 err = -EADDRINUSE;
193 goto done;
194 }
195
196 if (psm) {
197 chan->psm = psm;
198 chan->sport = psm;
199 err = 0;
200 } else {
201 u16 p, start, end, incr;
202
203 if (chan->src_type == BDADDR_BREDR) {
204 start = L2CAP_PSM_DYN_START;
205 end = L2CAP_PSM_AUTO_END;
206 incr = 2;
207 } else {
208 start = L2CAP_PSM_LE_DYN_START;
209 end = L2CAP_PSM_LE_DYN_END;
210 incr = 1;
211 }
212
213 err = -EINVAL;
214 for (p = start; p <= end; p += incr)
215 if (!__l2cap_global_chan_by_addr(cpu_to_le16(p), src)) {
216 chan->psm = cpu_to_le16(p);
217 chan->sport = cpu_to_le16(p);
218 err = 0;
219 break;
220 }
221 }
222
223 done:
224 write_unlock(&chan_list_lock);
225 return err;
226 }
227 EXPORT_SYMBOL_GPL(l2cap_add_psm);
228
229 int l2cap_add_scid(struct l2cap_chan *chan, __u16 scid)
230 {
231 write_lock(&chan_list_lock);
232
233 /* Override the defaults (which are for conn-oriented) */
234 chan->omtu = L2CAP_DEFAULT_MTU;
235 chan->chan_type = L2CAP_CHAN_FIXED;
236
237 chan->scid = scid;
238
239 write_unlock(&chan_list_lock);
240
241 return 0;
242 }
243
244 static u16 l2cap_alloc_cid(struct l2cap_conn *conn)
245 {
246 u16 cid, dyn_end;
247
248 if (conn->hcon->type == LE_LINK)
249 dyn_end = L2CAP_CID_LE_DYN_END;
250 else
251 dyn_end = L2CAP_CID_DYN_END;
252
253 for (cid = L2CAP_CID_DYN_START; cid <= dyn_end; cid++) {
254 if (!__l2cap_get_chan_by_scid(conn, cid))
255 return cid;
256 }
257
258 return 0;
259 }
260
261 static void l2cap_state_change(struct l2cap_chan *chan, int state)
262 {
263 BT_DBG("chan %p %s -> %s", chan, state_to_string(chan->state),
264 state_to_string(state));
265
266 chan->state = state;
267 chan->ops->state_change(chan, state, 0);
268 }
269
270 static inline void l2cap_state_change_and_error(struct l2cap_chan *chan,
271 int state, int err)
272 {
273 chan->state = state;
274 chan->ops->state_change(chan, chan->state, err);
275 }
276
277 static inline void l2cap_chan_set_err(struct l2cap_chan *chan, int err)
278 {
279 chan->ops->state_change(chan, chan->state, err);
280 }
281
282 static void __set_retrans_timer(struct l2cap_chan *chan)
283 {
284 if (!delayed_work_pending(&chan->monitor_timer) &&
285 chan->retrans_timeout) {
286 l2cap_set_timer(chan, &chan->retrans_timer,
287 msecs_to_jiffies(chan->retrans_timeout));
288 }
289 }
290
291 static void __set_monitor_timer(struct l2cap_chan *chan)
292 {
293 __clear_retrans_timer(chan);
294 if (chan->monitor_timeout) {
295 l2cap_set_timer(chan, &chan->monitor_timer,
296 msecs_to_jiffies(chan->monitor_timeout));
297 }
298 }
299
300 static struct sk_buff *l2cap_ertm_seq_in_queue(struct sk_buff_head *head,
301 u16 seq)
302 {
303 struct sk_buff *skb;
304
305 skb_queue_walk(head, skb) {
306 if (bt_cb(skb)->l2cap.txseq == seq)
307 return skb;
308 }
309
310 return NULL;
311 }
312
313 /* ---- L2CAP sequence number lists ---- */
314
315 /* For ERTM, ordered lists of sequence numbers must be tracked for
316 * SREJ requests that are received and for frames that are to be
317 * retransmitted. These seq_list functions implement a singly-linked
318 * list in an array, where membership in the list can also be checked
319 * in constant time. Items can also be added to the tail of the list
320 * and removed from the head in constant time, without further memory
321 * allocs or frees.
322 */
323
324 static int l2cap_seq_list_init(struct l2cap_seq_list *seq_list, u16 size)
325 {
326 size_t alloc_size, i;
327
328 /* Allocated size is a power of 2 to map sequence numbers
329 * (which may be up to 14 bits) in to a smaller array that is
330 * sized for the negotiated ERTM transmit windows.
331 */
332 alloc_size = roundup_pow_of_two(size);
333
334 seq_list->list = kmalloc(sizeof(u16) * alloc_size, GFP_KERNEL);
335 if (!seq_list->list)
336 return -ENOMEM;
337
338 seq_list->mask = alloc_size - 1;
339 seq_list->head = L2CAP_SEQ_LIST_CLEAR;
340 seq_list->tail = L2CAP_SEQ_LIST_CLEAR;
341 for (i = 0; i < alloc_size; i++)
342 seq_list->list[i] = L2CAP_SEQ_LIST_CLEAR;
343
344 return 0;
345 }
346
347 static inline void l2cap_seq_list_free(struct l2cap_seq_list *seq_list)
348 {
349 kfree(seq_list->list);
350 }
351
352 static inline bool l2cap_seq_list_contains(struct l2cap_seq_list *seq_list,
353 u16 seq)
354 {
355 /* Constant-time check for list membership */
356 return seq_list->list[seq & seq_list->mask] != L2CAP_SEQ_LIST_CLEAR;
357 }
358
359 static inline u16 l2cap_seq_list_pop(struct l2cap_seq_list *seq_list)
360 {
361 u16 seq = seq_list->head;
362 u16 mask = seq_list->mask;
363
364 seq_list->head = seq_list->list[seq & mask];
365 seq_list->list[seq & mask] = L2CAP_SEQ_LIST_CLEAR;
366
367 if (seq_list->head == L2CAP_SEQ_LIST_TAIL) {
368 seq_list->head = L2CAP_SEQ_LIST_CLEAR;
369 seq_list->tail = L2CAP_SEQ_LIST_CLEAR;
370 }
371
372 return seq;
373 }
374
375 static void l2cap_seq_list_clear(struct l2cap_seq_list *seq_list)
376 {
377 u16 i;
378
379 if (seq_list->head == L2CAP_SEQ_LIST_CLEAR)
380 return;
381
382 for (i = 0; i <= seq_list->mask; i++)
383 seq_list->list[i] = L2CAP_SEQ_LIST_CLEAR;
384
385 seq_list->head = L2CAP_SEQ_LIST_CLEAR;
386 seq_list->tail = L2CAP_SEQ_LIST_CLEAR;
387 }
388
389 static void l2cap_seq_list_append(struct l2cap_seq_list *seq_list, u16 seq)
390 {
391 u16 mask = seq_list->mask;
392
393 /* All appends happen in constant time */
394
395 if (seq_list->list[seq & mask] != L2CAP_SEQ_LIST_CLEAR)
396 return;
397
398 if (seq_list->tail == L2CAP_SEQ_LIST_CLEAR)
399 seq_list->head = seq;
400 else
401 seq_list->list[seq_list->tail & mask] = seq;
402
403 seq_list->tail = seq;
404 seq_list->list[seq & mask] = L2CAP_SEQ_LIST_TAIL;
405 }
406
407 static void l2cap_chan_timeout(struct work_struct *work)
408 {
409 struct l2cap_chan *chan = container_of(work, struct l2cap_chan,
410 chan_timer.work);
411 struct l2cap_conn *conn = chan->conn;
412 int reason;
413
414 BT_DBG("chan %p state %s", chan, state_to_string(chan->state));
415
416 mutex_lock(&conn->chan_lock);
417 l2cap_chan_lock(chan);
418
419 if (chan->state == BT_CONNECTED || chan->state == BT_CONFIG)
420 reason = ECONNREFUSED;
421 else if (chan->state == BT_CONNECT &&
422 chan->sec_level != BT_SECURITY_SDP)
423 reason = ECONNREFUSED;
424 else
425 reason = ETIMEDOUT;
426
427 l2cap_chan_close(chan, reason);
428
429 l2cap_chan_unlock(chan);
430
431 chan->ops->close(chan);
432 mutex_unlock(&conn->chan_lock);
433
434 l2cap_chan_put(chan);
435 }
436
437 struct l2cap_chan *l2cap_chan_create(void)
438 {
439 struct l2cap_chan *chan;
440
441 chan = kzalloc(sizeof(*chan), GFP_ATOMIC);
442 if (!chan)
443 return NULL;
444
445 mutex_init(&chan->lock);
446
447 /* Set default lock nesting level */
448 atomic_set(&chan->nesting, L2CAP_NESTING_NORMAL);
449
450 write_lock(&chan_list_lock);
451 list_add(&chan->global_l, &chan_list);
452 write_unlock(&chan_list_lock);
453
454 INIT_DELAYED_WORK(&chan->chan_timer, l2cap_chan_timeout);
455
456 chan->state = BT_OPEN;
457
458 kref_init(&chan->kref);
459
460 /* This flag is cleared in l2cap_chan_ready() */
461 set_bit(CONF_NOT_COMPLETE, &chan->conf_state);
462
463 BT_DBG("chan %p", chan);
464
465 return chan;
466 }
467 EXPORT_SYMBOL_GPL(l2cap_chan_create);
468
469 static void l2cap_chan_destroy(struct kref *kref)
470 {
471 struct l2cap_chan *chan = container_of(kref, struct l2cap_chan, kref);
472
473 BT_DBG("chan %p", chan);
474
475 write_lock(&chan_list_lock);
476 list_del(&chan->global_l);
477 write_unlock(&chan_list_lock);
478
479 kfree(chan);
480 }
481
482 void l2cap_chan_hold(struct l2cap_chan *c)
483 {
484 BT_DBG("chan %p orig refcnt %d", c, atomic_read(&c->kref.refcount));
485
486 kref_get(&c->kref);
487 }
488
489 void l2cap_chan_put(struct l2cap_chan *c)
490 {
491 BT_DBG("chan %p orig refcnt %d", c, atomic_read(&c->kref.refcount));
492
493 kref_put(&c->kref, l2cap_chan_destroy);
494 }
495 EXPORT_SYMBOL_GPL(l2cap_chan_put);
496
497 void l2cap_chan_set_defaults(struct l2cap_chan *chan)
498 {
499 chan->fcs = L2CAP_FCS_CRC16;
500 chan->max_tx = L2CAP_DEFAULT_MAX_TX;
501 chan->tx_win = L2CAP_DEFAULT_TX_WINDOW;
502 chan->tx_win_max = L2CAP_DEFAULT_TX_WINDOW;
503 chan->remote_max_tx = chan->max_tx;
504 chan->remote_tx_win = chan->tx_win;
505 chan->ack_win = L2CAP_DEFAULT_TX_WINDOW;
506 chan->sec_level = BT_SECURITY_LOW;
507 chan->flush_to = L2CAP_DEFAULT_FLUSH_TO;
508 chan->retrans_timeout = L2CAP_DEFAULT_RETRANS_TO;
509 chan->monitor_timeout = L2CAP_DEFAULT_MONITOR_TO;
510 chan->conf_state = 0;
511
512 set_bit(FLAG_FORCE_ACTIVE, &chan->flags);
513 }
514 EXPORT_SYMBOL_GPL(l2cap_chan_set_defaults);
515
516 static void l2cap_le_flowctl_init(struct l2cap_chan *chan)
517 {
518 chan->sdu = NULL;
519 chan->sdu_last_frag = NULL;
520 chan->sdu_len = 0;
521 chan->tx_credits = 0;
522 chan->rx_credits = le_max_credits;
523 chan->mps = min_t(u16, chan->imtu, le_default_mps);
524
525 skb_queue_head_init(&chan->tx_q);
526 }
527
528 void __l2cap_chan_add(struct l2cap_conn *conn, struct l2cap_chan *chan)
529 {
530 BT_DBG("conn %p, psm 0x%2.2x, dcid 0x%4.4x", conn,
531 __le16_to_cpu(chan->psm), chan->dcid);
532
533 conn->disc_reason = HCI_ERROR_REMOTE_USER_TERM;
534
535 chan->conn = conn;
536
537 switch (chan->chan_type) {
538 case L2CAP_CHAN_CONN_ORIENTED:
539 /* Alloc CID for connection-oriented socket */
540 chan->scid = l2cap_alloc_cid(conn);
541 if (conn->hcon->type == ACL_LINK)
542 chan->omtu = L2CAP_DEFAULT_MTU;
543 break;
544
545 case L2CAP_CHAN_CONN_LESS:
546 /* Connectionless socket */
547 chan->scid = L2CAP_CID_CONN_LESS;
548 chan->dcid = L2CAP_CID_CONN_LESS;
549 chan->omtu = L2CAP_DEFAULT_MTU;
550 break;
551
552 case L2CAP_CHAN_FIXED:
553 /* Caller will set CID and CID specific MTU values */
554 break;
555
556 default:
557 /* Raw socket can send/recv signalling messages only */
558 chan->scid = L2CAP_CID_SIGNALING;
559 chan->dcid = L2CAP_CID_SIGNALING;
560 chan->omtu = L2CAP_DEFAULT_MTU;
561 }
562
563 chan->local_id = L2CAP_BESTEFFORT_ID;
564 chan->local_stype = L2CAP_SERV_BESTEFFORT;
565 chan->local_msdu = L2CAP_DEFAULT_MAX_SDU_SIZE;
566 chan->local_sdu_itime = L2CAP_DEFAULT_SDU_ITIME;
567 chan->local_acc_lat = L2CAP_DEFAULT_ACC_LAT;
568 chan->local_flush_to = L2CAP_EFS_DEFAULT_FLUSH_TO;
569
570 l2cap_chan_hold(chan);
571
572 /* Only keep a reference for fixed channels if they requested it */
573 if (chan->chan_type != L2CAP_CHAN_FIXED ||
574 test_bit(FLAG_HOLD_HCI_CONN, &chan->flags))
575 hci_conn_hold(conn->hcon);
576
577 list_add(&chan->list, &conn->chan_l);
578 }
579
580 void l2cap_chan_add(struct l2cap_conn *conn, struct l2cap_chan *chan)
581 {
582 mutex_lock(&conn->chan_lock);
583 __l2cap_chan_add(conn, chan);
584 mutex_unlock(&conn->chan_lock);
585 }
586
587 void l2cap_chan_del(struct l2cap_chan *chan, int err)
588 {
589 struct l2cap_conn *conn = chan->conn;
590
591 __clear_chan_timer(chan);
592
593 BT_DBG("chan %p, conn %p, err %d, state %s", chan, conn, err,
594 state_to_string(chan->state));
595
596 chan->ops->teardown(chan, err);
597
598 if (conn) {
599 struct amp_mgr *mgr = conn->hcon->amp_mgr;
600 /* Delete from channel list */
601 list_del(&chan->list);
602
603 l2cap_chan_put(chan);
604
605 chan->conn = NULL;
606
607 /* Reference was only held for non-fixed channels or
608 * fixed channels that explicitly requested it using the
609 * FLAG_HOLD_HCI_CONN flag.
610 */
611 if (chan->chan_type != L2CAP_CHAN_FIXED ||
612 test_bit(FLAG_HOLD_HCI_CONN, &chan->flags))
613 hci_conn_drop(conn->hcon);
614
615 if (mgr && mgr->bredr_chan == chan)
616 mgr->bredr_chan = NULL;
617 }
618
619 if (chan->hs_hchan) {
620 struct hci_chan *hs_hchan = chan->hs_hchan;
621
622 BT_DBG("chan %p disconnect hs_hchan %p", chan, hs_hchan);
623 amp_disconnect_logical_link(hs_hchan);
624 }
625
626 if (test_bit(CONF_NOT_COMPLETE, &chan->conf_state))
627 return;
628
629 switch(chan->mode) {
630 case L2CAP_MODE_BASIC:
631 break;
632
633 case L2CAP_MODE_LE_FLOWCTL:
634 skb_queue_purge(&chan->tx_q);
635 break;
636
637 case L2CAP_MODE_ERTM:
638 __clear_retrans_timer(chan);
639 __clear_monitor_timer(chan);
640 __clear_ack_timer(chan);
641
642 skb_queue_purge(&chan->srej_q);
643
644 l2cap_seq_list_free(&chan->srej_list);
645 l2cap_seq_list_free(&chan->retrans_list);
646
647 /* fall through */
648
649 case L2CAP_MODE_STREAMING:
650 skb_queue_purge(&chan->tx_q);
651 break;
652 }
653
654 return;
655 }
656 EXPORT_SYMBOL_GPL(l2cap_chan_del);
657
658 static void l2cap_conn_update_id_addr(struct work_struct *work)
659 {
660 struct l2cap_conn *conn = container_of(work, struct l2cap_conn,
661 id_addr_update_work);
662 struct hci_conn *hcon = conn->hcon;
663 struct l2cap_chan *chan;
664
665 mutex_lock(&conn->chan_lock);
666
667 list_for_each_entry(chan, &conn->chan_l, list) {
668 l2cap_chan_lock(chan);
669 bacpy(&chan->dst, &hcon->dst);
670 chan->dst_type = bdaddr_dst_type(hcon);
671 l2cap_chan_unlock(chan);
672 }
673
674 mutex_unlock(&conn->chan_lock);
675 }
676
677 static void l2cap_chan_le_connect_reject(struct l2cap_chan *chan)
678 {
679 struct l2cap_conn *conn = chan->conn;
680 struct l2cap_le_conn_rsp rsp;
681 u16 result;
682
683 if (test_bit(FLAG_DEFER_SETUP, &chan->flags))
684 result = L2CAP_CR_AUTHORIZATION;
685 else
686 result = L2CAP_CR_BAD_PSM;
687
688 l2cap_state_change(chan, BT_DISCONN);
689
690 rsp.dcid = cpu_to_le16(chan->scid);
691 rsp.mtu = cpu_to_le16(chan->imtu);
692 rsp.mps = cpu_to_le16(chan->mps);
693 rsp.credits = cpu_to_le16(chan->rx_credits);
694 rsp.result = cpu_to_le16(result);
695
696 l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CONN_RSP, sizeof(rsp),
697 &rsp);
698 }
699
700 static void l2cap_chan_connect_reject(struct l2cap_chan *chan)
701 {
702 struct l2cap_conn *conn = chan->conn;
703 struct l2cap_conn_rsp rsp;
704 u16 result;
705
706 if (test_bit(FLAG_DEFER_SETUP, &chan->flags))
707 result = L2CAP_CR_SEC_BLOCK;
708 else
709 result = L2CAP_CR_BAD_PSM;
710
711 l2cap_state_change(chan, BT_DISCONN);
712
713 rsp.scid = cpu_to_le16(chan->dcid);
714 rsp.dcid = cpu_to_le16(chan->scid);
715 rsp.result = cpu_to_le16(result);
716 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
717
718 l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_RSP, sizeof(rsp), &rsp);
719 }
720
721 void l2cap_chan_close(struct l2cap_chan *chan, int reason)
722 {
723 struct l2cap_conn *conn = chan->conn;
724
725 BT_DBG("chan %p state %s", chan, state_to_string(chan->state));
726
727 switch (chan->state) {
728 case BT_LISTEN:
729 chan->ops->teardown(chan, 0);
730 break;
731
732 case BT_CONNECTED:
733 case BT_CONFIG:
734 if (chan->chan_type == L2CAP_CHAN_CONN_ORIENTED) {
735 __set_chan_timer(chan, chan->ops->get_sndtimeo(chan));
736 l2cap_send_disconn_req(chan, reason);
737 } else
738 l2cap_chan_del(chan, reason);
739 break;
740
741 case BT_CONNECT2:
742 if (chan->chan_type == L2CAP_CHAN_CONN_ORIENTED) {
743 if (conn->hcon->type == ACL_LINK)
744 l2cap_chan_connect_reject(chan);
745 else if (conn->hcon->type == LE_LINK)
746 l2cap_chan_le_connect_reject(chan);
747 }
748
749 l2cap_chan_del(chan, reason);
750 break;
751
752 case BT_CONNECT:
753 case BT_DISCONN:
754 l2cap_chan_del(chan, reason);
755 break;
756
757 default:
758 chan->ops->teardown(chan, 0);
759 break;
760 }
761 }
762 EXPORT_SYMBOL(l2cap_chan_close);
763
764 static inline u8 l2cap_get_auth_type(struct l2cap_chan *chan)
765 {
766 switch (chan->chan_type) {
767 case L2CAP_CHAN_RAW:
768 switch (chan->sec_level) {
769 case BT_SECURITY_HIGH:
770 case BT_SECURITY_FIPS:
771 return HCI_AT_DEDICATED_BONDING_MITM;
772 case BT_SECURITY_MEDIUM:
773 return HCI_AT_DEDICATED_BONDING;
774 default:
775 return HCI_AT_NO_BONDING;
776 }
777 break;
778 case L2CAP_CHAN_CONN_LESS:
779 if (chan->psm == cpu_to_le16(L2CAP_PSM_3DSP)) {
780 if (chan->sec_level == BT_SECURITY_LOW)
781 chan->sec_level = BT_SECURITY_SDP;
782 }
783 if (chan->sec_level == BT_SECURITY_HIGH ||
784 chan->sec_level == BT_SECURITY_FIPS)
785 return HCI_AT_NO_BONDING_MITM;
786 else
787 return HCI_AT_NO_BONDING;
788 break;
789 case L2CAP_CHAN_CONN_ORIENTED:
790 if (chan->psm == cpu_to_le16(L2CAP_PSM_SDP)) {
791 if (chan->sec_level == BT_SECURITY_LOW)
792 chan->sec_level = BT_SECURITY_SDP;
793
794 if (chan->sec_level == BT_SECURITY_HIGH ||
795 chan->sec_level == BT_SECURITY_FIPS)
796 return HCI_AT_NO_BONDING_MITM;
797 else
798 return HCI_AT_NO_BONDING;
799 }
800 /* fall through */
801 default:
802 switch (chan->sec_level) {
803 case BT_SECURITY_HIGH:
804 case BT_SECURITY_FIPS:
805 return HCI_AT_GENERAL_BONDING_MITM;
806 case BT_SECURITY_MEDIUM:
807 return HCI_AT_GENERAL_BONDING;
808 default:
809 return HCI_AT_NO_BONDING;
810 }
811 break;
812 }
813 }
814
815 /* Service level security */
816 int l2cap_chan_check_security(struct l2cap_chan *chan, bool initiator)
817 {
818 struct l2cap_conn *conn = chan->conn;
819 __u8 auth_type;
820
821 if (conn->hcon->type == LE_LINK)
822 return smp_conn_security(conn->hcon, chan->sec_level);
823
824 auth_type = l2cap_get_auth_type(chan);
825
826 return hci_conn_security(conn->hcon, chan->sec_level, auth_type,
827 initiator);
828 }
829
830 static u8 l2cap_get_ident(struct l2cap_conn *conn)
831 {
832 u8 id;
833
834 /* Get next available identificator.
835 * 1 - 128 are used by kernel.
836 * 129 - 199 are reserved.
837 * 200 - 254 are used by utilities like l2ping, etc.
838 */
839
840 mutex_lock(&conn->ident_lock);
841
842 if (++conn->tx_ident > 128)
843 conn->tx_ident = 1;
844
845 id = conn->tx_ident;
846
847 mutex_unlock(&conn->ident_lock);
848
849 return id;
850 }
851
852 static void l2cap_send_cmd(struct l2cap_conn *conn, u8 ident, u8 code, u16 len,
853 void *data)
854 {
855 struct sk_buff *skb = l2cap_build_cmd(conn, code, ident, len, data);
856 u8 flags;
857
858 BT_DBG("code 0x%2.2x", code);
859
860 if (!skb)
861 return;
862
863 /* Use NO_FLUSH if supported or we have an LE link (which does
864 * not support auto-flushing packets) */
865 if (lmp_no_flush_capable(conn->hcon->hdev) ||
866 conn->hcon->type == LE_LINK)
867 flags = ACL_START_NO_FLUSH;
868 else
869 flags = ACL_START;
870
871 bt_cb(skb)->force_active = BT_POWER_FORCE_ACTIVE_ON;
872 skb->priority = HCI_PRIO_MAX;
873
874 hci_send_acl(conn->hchan, skb, flags);
875 }
876
877 static bool __chan_is_moving(struct l2cap_chan *chan)
878 {
879 return chan->move_state != L2CAP_MOVE_STABLE &&
880 chan->move_state != L2CAP_MOVE_WAIT_PREPARE;
881 }
882
883 static void l2cap_do_send(struct l2cap_chan *chan, struct sk_buff *skb)
884 {
885 struct hci_conn *hcon = chan->conn->hcon;
886 u16 flags;
887
888 BT_DBG("chan %p, skb %p len %d priority %u", chan, skb, skb->len,
889 skb->priority);
890
891 if (chan->hs_hcon && !__chan_is_moving(chan)) {
892 if (chan->hs_hchan)
893 hci_send_acl(chan->hs_hchan, skb, ACL_COMPLETE);
894 else
895 kfree_skb(skb);
896
897 return;
898 }
899
900 /* Use NO_FLUSH for LE links (where this is the only option) or
901 * if the BR/EDR link supports it and flushing has not been
902 * explicitly requested (through FLAG_FLUSHABLE).
903 */
904 if (hcon->type == LE_LINK ||
905 (!test_bit(FLAG_FLUSHABLE, &chan->flags) &&
906 lmp_no_flush_capable(hcon->hdev)))
907 flags = ACL_START_NO_FLUSH;
908 else
909 flags = ACL_START;
910
911 bt_cb(skb)->force_active = test_bit(FLAG_FORCE_ACTIVE, &chan->flags);
912 hci_send_acl(chan->conn->hchan, skb, flags);
913 }
914
915 static void __unpack_enhanced_control(u16 enh, struct l2cap_ctrl *control)
916 {
917 control->reqseq = (enh & L2CAP_CTRL_REQSEQ) >> L2CAP_CTRL_REQSEQ_SHIFT;
918 control->final = (enh & L2CAP_CTRL_FINAL) >> L2CAP_CTRL_FINAL_SHIFT;
919
920 if (enh & L2CAP_CTRL_FRAME_TYPE) {
921 /* S-Frame */
922 control->sframe = 1;
923 control->poll = (enh & L2CAP_CTRL_POLL) >> L2CAP_CTRL_POLL_SHIFT;
924 control->super = (enh & L2CAP_CTRL_SUPERVISE) >> L2CAP_CTRL_SUPER_SHIFT;
925
926 control->sar = 0;
927 control->txseq = 0;
928 } else {
929 /* I-Frame */
930 control->sframe = 0;
931 control->sar = (enh & L2CAP_CTRL_SAR) >> L2CAP_CTRL_SAR_SHIFT;
932 control->txseq = (enh & L2CAP_CTRL_TXSEQ) >> L2CAP_CTRL_TXSEQ_SHIFT;
933
934 control->poll = 0;
935 control->super = 0;
936 }
937 }
938
939 static void __unpack_extended_control(u32 ext, struct l2cap_ctrl *control)
940 {
941 control->reqseq = (ext & L2CAP_EXT_CTRL_REQSEQ) >> L2CAP_EXT_CTRL_REQSEQ_SHIFT;
942 control->final = (ext & L2CAP_EXT_CTRL_FINAL) >> L2CAP_EXT_CTRL_FINAL_SHIFT;
943
944 if (ext & L2CAP_EXT_CTRL_FRAME_TYPE) {
945 /* S-Frame */
946 control->sframe = 1;
947 control->poll = (ext & L2CAP_EXT_CTRL_POLL) >> L2CAP_EXT_CTRL_POLL_SHIFT;
948 control->super = (ext & L2CAP_EXT_CTRL_SUPERVISE) >> L2CAP_EXT_CTRL_SUPER_SHIFT;
949
950 control->sar = 0;
951 control->txseq = 0;
952 } else {
953 /* I-Frame */
954 control->sframe = 0;
955 control->sar = (ext & L2CAP_EXT_CTRL_SAR) >> L2CAP_EXT_CTRL_SAR_SHIFT;
956 control->txseq = (ext & L2CAP_EXT_CTRL_TXSEQ) >> L2CAP_EXT_CTRL_TXSEQ_SHIFT;
957
958 control->poll = 0;
959 control->super = 0;
960 }
961 }
962
963 static inline void __unpack_control(struct l2cap_chan *chan,
964 struct sk_buff *skb)
965 {
966 if (test_bit(FLAG_EXT_CTRL, &chan->flags)) {
967 __unpack_extended_control(get_unaligned_le32(skb->data),
968 &bt_cb(skb)->l2cap);
969 skb_pull(skb, L2CAP_EXT_CTRL_SIZE);
970 } else {
971 __unpack_enhanced_control(get_unaligned_le16(skb->data),
972 &bt_cb(skb)->l2cap);
973 skb_pull(skb, L2CAP_ENH_CTRL_SIZE);
974 }
975 }
976
977 static u32 __pack_extended_control(struct l2cap_ctrl *control)
978 {
979 u32 packed;
980
981 packed = control->reqseq << L2CAP_EXT_CTRL_REQSEQ_SHIFT;
982 packed |= control->final << L2CAP_EXT_CTRL_FINAL_SHIFT;
983
984 if (control->sframe) {
985 packed |= control->poll << L2CAP_EXT_CTRL_POLL_SHIFT;
986 packed |= control->super << L2CAP_EXT_CTRL_SUPER_SHIFT;
987 packed |= L2CAP_EXT_CTRL_FRAME_TYPE;
988 } else {
989 packed |= control->sar << L2CAP_EXT_CTRL_SAR_SHIFT;
990 packed |= control->txseq << L2CAP_EXT_CTRL_TXSEQ_SHIFT;
991 }
992
993 return packed;
994 }
995
996 static u16 __pack_enhanced_control(struct l2cap_ctrl *control)
997 {
998 u16 packed;
999
1000 packed = control->reqseq << L2CAP_CTRL_REQSEQ_SHIFT;
1001 packed |= control->final << L2CAP_CTRL_FINAL_SHIFT;
1002
1003 if (control->sframe) {
1004 packed |= control->poll << L2CAP_CTRL_POLL_SHIFT;
1005 packed |= control->super << L2CAP_CTRL_SUPER_SHIFT;
1006 packed |= L2CAP_CTRL_FRAME_TYPE;
1007 } else {
1008 packed |= control->sar << L2CAP_CTRL_SAR_SHIFT;
1009 packed |= control->txseq << L2CAP_CTRL_TXSEQ_SHIFT;
1010 }
1011
1012 return packed;
1013 }
1014
1015 static inline void __pack_control(struct l2cap_chan *chan,
1016 struct l2cap_ctrl *control,
1017 struct sk_buff *skb)
1018 {
1019 if (test_bit(FLAG_EXT_CTRL, &chan->flags)) {
1020 put_unaligned_le32(__pack_extended_control(control),
1021 skb->data + L2CAP_HDR_SIZE);
1022 } else {
1023 put_unaligned_le16(__pack_enhanced_control(control),
1024 skb->data + L2CAP_HDR_SIZE);
1025 }
1026 }
1027
1028 static inline unsigned int __ertm_hdr_size(struct l2cap_chan *chan)
1029 {
1030 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
1031 return L2CAP_EXT_HDR_SIZE;
1032 else
1033 return L2CAP_ENH_HDR_SIZE;
1034 }
1035
1036 static struct sk_buff *l2cap_create_sframe_pdu(struct l2cap_chan *chan,
1037 u32 control)
1038 {
1039 struct sk_buff *skb;
1040 struct l2cap_hdr *lh;
1041 int hlen = __ertm_hdr_size(chan);
1042
1043 if (chan->fcs == L2CAP_FCS_CRC16)
1044 hlen += L2CAP_FCS_SIZE;
1045
1046 skb = bt_skb_alloc(hlen, GFP_KERNEL);
1047
1048 if (!skb)
1049 return ERR_PTR(-ENOMEM);
1050
1051 lh = (struct l2cap_hdr *) skb_put(skb, L2CAP_HDR_SIZE);
1052 lh->len = cpu_to_le16(hlen - L2CAP_HDR_SIZE);
1053 lh->cid = cpu_to_le16(chan->dcid);
1054
1055 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
1056 put_unaligned_le32(control, skb_put(skb, L2CAP_EXT_CTRL_SIZE));
1057 else
1058 put_unaligned_le16(control, skb_put(skb, L2CAP_ENH_CTRL_SIZE));
1059
1060 if (chan->fcs == L2CAP_FCS_CRC16) {
1061 u16 fcs = crc16(0, (u8 *)skb->data, skb->len);
1062 put_unaligned_le16(fcs, skb_put(skb, L2CAP_FCS_SIZE));
1063 }
1064
1065 skb->priority = HCI_PRIO_MAX;
1066 return skb;
1067 }
1068
1069 static void l2cap_send_sframe(struct l2cap_chan *chan,
1070 struct l2cap_ctrl *control)
1071 {
1072 struct sk_buff *skb;
1073 u32 control_field;
1074
1075 BT_DBG("chan %p, control %p", chan, control);
1076
1077 if (!control->sframe)
1078 return;
1079
1080 if (__chan_is_moving(chan))
1081 return;
1082
1083 if (test_and_clear_bit(CONN_SEND_FBIT, &chan->conn_state) &&
1084 !control->poll)
1085 control->final = 1;
1086
1087 if (control->super == L2CAP_SUPER_RR)
1088 clear_bit(CONN_RNR_SENT, &chan->conn_state);
1089 else if (control->super == L2CAP_SUPER_RNR)
1090 set_bit(CONN_RNR_SENT, &chan->conn_state);
1091
1092 if (control->super != L2CAP_SUPER_SREJ) {
1093 chan->last_acked_seq = control->reqseq;
1094 __clear_ack_timer(chan);
1095 }
1096
1097 BT_DBG("reqseq %d, final %d, poll %d, super %d", control->reqseq,
1098 control->final, control->poll, control->super);
1099
1100 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
1101 control_field = __pack_extended_control(control);
1102 else
1103 control_field = __pack_enhanced_control(control);
1104
1105 skb = l2cap_create_sframe_pdu(chan, control_field);
1106 if (!IS_ERR(skb))
1107 l2cap_do_send(chan, skb);
1108 }
1109
1110 static void l2cap_send_rr_or_rnr(struct l2cap_chan *chan, bool poll)
1111 {
1112 struct l2cap_ctrl control;
1113
1114 BT_DBG("chan %p, poll %d", chan, poll);
1115
1116 memset(&control, 0, sizeof(control));
1117 control.sframe = 1;
1118 control.poll = poll;
1119
1120 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state))
1121 control.super = L2CAP_SUPER_RNR;
1122 else
1123 control.super = L2CAP_SUPER_RR;
1124
1125 control.reqseq = chan->buffer_seq;
1126 l2cap_send_sframe(chan, &control);
1127 }
1128
1129 static inline int __l2cap_no_conn_pending(struct l2cap_chan *chan)
1130 {
1131 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED)
1132 return true;
1133
1134 return !test_bit(CONF_CONNECT_PEND, &chan->conf_state);
1135 }
1136
1137 static bool __amp_capable(struct l2cap_chan *chan)
1138 {
1139 struct l2cap_conn *conn = chan->conn;
1140 struct hci_dev *hdev;
1141 bool amp_available = false;
1142
1143 if (!(conn->local_fixed_chan & L2CAP_FC_A2MP))
1144 return false;
1145
1146 if (!(conn->remote_fixed_chan & L2CAP_FC_A2MP))
1147 return false;
1148
1149 read_lock(&hci_dev_list_lock);
1150 list_for_each_entry(hdev, &hci_dev_list, list) {
1151 if (hdev->amp_type != AMP_TYPE_BREDR &&
1152 test_bit(HCI_UP, &hdev->flags)) {
1153 amp_available = true;
1154 break;
1155 }
1156 }
1157 read_unlock(&hci_dev_list_lock);
1158
1159 if (chan->chan_policy == BT_CHANNEL_POLICY_AMP_PREFERRED)
1160 return amp_available;
1161
1162 return false;
1163 }
1164
1165 static bool l2cap_check_efs(struct l2cap_chan *chan)
1166 {
1167 /* Check EFS parameters */
1168 return true;
1169 }
1170
1171 void l2cap_send_conn_req(struct l2cap_chan *chan)
1172 {
1173 struct l2cap_conn *conn = chan->conn;
1174 struct l2cap_conn_req req;
1175
1176 req.scid = cpu_to_le16(chan->scid);
1177 req.psm = chan->psm;
1178
1179 chan->ident = l2cap_get_ident(conn);
1180
1181 set_bit(CONF_CONNECT_PEND, &chan->conf_state);
1182
1183 l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_REQ, sizeof(req), &req);
1184 }
1185
1186 static void l2cap_send_create_chan_req(struct l2cap_chan *chan, u8 amp_id)
1187 {
1188 struct l2cap_create_chan_req req;
1189 req.scid = cpu_to_le16(chan->scid);
1190 req.psm = chan->psm;
1191 req.amp_id = amp_id;
1192
1193 chan->ident = l2cap_get_ident(chan->conn);
1194
1195 l2cap_send_cmd(chan->conn, chan->ident, L2CAP_CREATE_CHAN_REQ,
1196 sizeof(req), &req);
1197 }
1198
1199 static void l2cap_move_setup(struct l2cap_chan *chan)
1200 {
1201 struct sk_buff *skb;
1202
1203 BT_DBG("chan %p", chan);
1204
1205 if (chan->mode != L2CAP_MODE_ERTM)
1206 return;
1207
1208 __clear_retrans_timer(chan);
1209 __clear_monitor_timer(chan);
1210 __clear_ack_timer(chan);
1211
1212 chan->retry_count = 0;
1213 skb_queue_walk(&chan->tx_q, skb) {
1214 if (bt_cb(skb)->l2cap.retries)
1215 bt_cb(skb)->l2cap.retries = 1;
1216 else
1217 break;
1218 }
1219
1220 chan->expected_tx_seq = chan->buffer_seq;
1221
1222 clear_bit(CONN_REJ_ACT, &chan->conn_state);
1223 clear_bit(CONN_SREJ_ACT, &chan->conn_state);
1224 l2cap_seq_list_clear(&chan->retrans_list);
1225 l2cap_seq_list_clear(&chan->srej_list);
1226 skb_queue_purge(&chan->srej_q);
1227
1228 chan->tx_state = L2CAP_TX_STATE_XMIT;
1229 chan->rx_state = L2CAP_RX_STATE_MOVE;
1230
1231 set_bit(CONN_REMOTE_BUSY, &chan->conn_state);
1232 }
1233
1234 static void l2cap_move_done(struct l2cap_chan *chan)
1235 {
1236 u8 move_role = chan->move_role;
1237 BT_DBG("chan %p", chan);
1238
1239 chan->move_state = L2CAP_MOVE_STABLE;
1240 chan->move_role = L2CAP_MOVE_ROLE_NONE;
1241
1242 if (chan->mode != L2CAP_MODE_ERTM)
1243 return;
1244
1245 switch (move_role) {
1246 case L2CAP_MOVE_ROLE_INITIATOR:
1247 l2cap_tx(chan, NULL, NULL, L2CAP_EV_EXPLICIT_POLL);
1248 chan->rx_state = L2CAP_RX_STATE_WAIT_F;
1249 break;
1250 case L2CAP_MOVE_ROLE_RESPONDER:
1251 chan->rx_state = L2CAP_RX_STATE_WAIT_P;
1252 break;
1253 }
1254 }
1255
1256 static void l2cap_chan_ready(struct l2cap_chan *chan)
1257 {
1258 /* The channel may have already been flagged as connected in
1259 * case of receiving data before the L2CAP info req/rsp
1260 * procedure is complete.
1261 */
1262 if (chan->state == BT_CONNECTED)
1263 return;
1264
1265 /* This clears all conf flags, including CONF_NOT_COMPLETE */
1266 chan->conf_state = 0;
1267 __clear_chan_timer(chan);
1268
1269 if (chan->mode == L2CAP_MODE_LE_FLOWCTL && !chan->tx_credits)
1270 chan->ops->suspend(chan);
1271
1272 chan->state = BT_CONNECTED;
1273
1274 chan->ops->ready(chan);
1275 }
1276
1277 static void l2cap_le_connect(struct l2cap_chan *chan)
1278 {
1279 struct l2cap_conn *conn = chan->conn;
1280 struct l2cap_le_conn_req req;
1281
1282 if (test_and_set_bit(FLAG_LE_CONN_REQ_SENT, &chan->flags))
1283 return;
1284
1285 req.psm = chan->psm;
1286 req.scid = cpu_to_le16(chan->scid);
1287 req.mtu = cpu_to_le16(chan->imtu);
1288 req.mps = cpu_to_le16(chan->mps);
1289 req.credits = cpu_to_le16(chan->rx_credits);
1290
1291 chan->ident = l2cap_get_ident(conn);
1292
1293 l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CONN_REQ,
1294 sizeof(req), &req);
1295 }
1296
1297 static void l2cap_le_start(struct l2cap_chan *chan)
1298 {
1299 struct l2cap_conn *conn = chan->conn;
1300
1301 if (!smp_conn_security(conn->hcon, chan->sec_level))
1302 return;
1303
1304 if (!chan->psm) {
1305 l2cap_chan_ready(chan);
1306 return;
1307 }
1308
1309 if (chan->state == BT_CONNECT)
1310 l2cap_le_connect(chan);
1311 }
1312
1313 static void l2cap_start_connection(struct l2cap_chan *chan)
1314 {
1315 if (__amp_capable(chan)) {
1316 BT_DBG("chan %p AMP capable: discover AMPs", chan);
1317 a2mp_discover_amp(chan);
1318 } else if (chan->conn->hcon->type == LE_LINK) {
1319 l2cap_le_start(chan);
1320 } else {
1321 l2cap_send_conn_req(chan);
1322 }
1323 }
1324
1325 static void l2cap_request_info(struct l2cap_conn *conn)
1326 {
1327 struct l2cap_info_req req;
1328
1329 if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT)
1330 return;
1331
1332 req.type = cpu_to_le16(L2CAP_IT_FEAT_MASK);
1333
1334 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_SENT;
1335 conn->info_ident = l2cap_get_ident(conn);
1336
1337 schedule_delayed_work(&conn->info_timer, L2CAP_INFO_TIMEOUT);
1338
1339 l2cap_send_cmd(conn, conn->info_ident, L2CAP_INFO_REQ,
1340 sizeof(req), &req);
1341 }
1342
1343 static void l2cap_do_start(struct l2cap_chan *chan)
1344 {
1345 struct l2cap_conn *conn = chan->conn;
1346
1347 if (conn->hcon->type == LE_LINK) {
1348 l2cap_le_start(chan);
1349 return;
1350 }
1351
1352 if (!(conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT)) {
1353 l2cap_request_info(conn);
1354 return;
1355 }
1356
1357 if (!(conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE))
1358 return;
1359
1360 if (l2cap_chan_check_security(chan, true) &&
1361 __l2cap_no_conn_pending(chan))
1362 l2cap_start_connection(chan);
1363 }
1364
1365 static inline int l2cap_mode_supported(__u8 mode, __u32 feat_mask)
1366 {
1367 u32 local_feat_mask = l2cap_feat_mask;
1368 if (!disable_ertm)
1369 local_feat_mask |= L2CAP_FEAT_ERTM | L2CAP_FEAT_STREAMING;
1370
1371 switch (mode) {
1372 case L2CAP_MODE_ERTM:
1373 return L2CAP_FEAT_ERTM & feat_mask & local_feat_mask;
1374 case L2CAP_MODE_STREAMING:
1375 return L2CAP_FEAT_STREAMING & feat_mask & local_feat_mask;
1376 default:
1377 return 0x00;
1378 }
1379 }
1380
1381 static void l2cap_send_disconn_req(struct l2cap_chan *chan, int err)
1382 {
1383 struct l2cap_conn *conn = chan->conn;
1384 struct l2cap_disconn_req req;
1385
1386 if (!conn)
1387 return;
1388
1389 if (chan->mode == L2CAP_MODE_ERTM && chan->state == BT_CONNECTED) {
1390 __clear_retrans_timer(chan);
1391 __clear_monitor_timer(chan);
1392 __clear_ack_timer(chan);
1393 }
1394
1395 if (chan->scid == L2CAP_CID_A2MP) {
1396 l2cap_state_change(chan, BT_DISCONN);
1397 return;
1398 }
1399
1400 req.dcid = cpu_to_le16(chan->dcid);
1401 req.scid = cpu_to_le16(chan->scid);
1402 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_DISCONN_REQ,
1403 sizeof(req), &req);
1404
1405 l2cap_state_change_and_error(chan, BT_DISCONN, err);
1406 }
1407
1408 /* ---- L2CAP connections ---- */
1409 static void l2cap_conn_start(struct l2cap_conn *conn)
1410 {
1411 struct l2cap_chan *chan, *tmp;
1412
1413 BT_DBG("conn %p", conn);
1414
1415 mutex_lock(&conn->chan_lock);
1416
1417 list_for_each_entry_safe(chan, tmp, &conn->chan_l, list) {
1418 l2cap_chan_lock(chan);
1419
1420 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) {
1421 l2cap_chan_ready(chan);
1422 l2cap_chan_unlock(chan);
1423 continue;
1424 }
1425
1426 if (chan->state == BT_CONNECT) {
1427 if (!l2cap_chan_check_security(chan, true) ||
1428 !__l2cap_no_conn_pending(chan)) {
1429 l2cap_chan_unlock(chan);
1430 continue;
1431 }
1432
1433 if (!l2cap_mode_supported(chan->mode, conn->feat_mask)
1434 && test_bit(CONF_STATE2_DEVICE,
1435 &chan->conf_state)) {
1436 l2cap_chan_close(chan, ECONNRESET);
1437 l2cap_chan_unlock(chan);
1438 continue;
1439 }
1440
1441 l2cap_start_connection(chan);
1442
1443 } else if (chan->state == BT_CONNECT2) {
1444 struct l2cap_conn_rsp rsp;
1445 char buf[128];
1446 rsp.scid = cpu_to_le16(chan->dcid);
1447 rsp.dcid = cpu_to_le16(chan->scid);
1448
1449 if (l2cap_chan_check_security(chan, false)) {
1450 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) {
1451 rsp.result = cpu_to_le16(L2CAP_CR_PEND);
1452 rsp.status = cpu_to_le16(L2CAP_CS_AUTHOR_PEND);
1453 chan->ops->defer(chan);
1454
1455 } else {
1456 l2cap_state_change(chan, BT_CONFIG);
1457 rsp.result = cpu_to_le16(L2CAP_CR_SUCCESS);
1458 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
1459 }
1460 } else {
1461 rsp.result = cpu_to_le16(L2CAP_CR_PEND);
1462 rsp.status = cpu_to_le16(L2CAP_CS_AUTHEN_PEND);
1463 }
1464
1465 l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_RSP,
1466 sizeof(rsp), &rsp);
1467
1468 if (test_bit(CONF_REQ_SENT, &chan->conf_state) ||
1469 rsp.result != L2CAP_CR_SUCCESS) {
1470 l2cap_chan_unlock(chan);
1471 continue;
1472 }
1473
1474 set_bit(CONF_REQ_SENT, &chan->conf_state);
1475 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
1476 l2cap_build_conf_req(chan, buf), buf);
1477 chan->num_conf_req++;
1478 }
1479
1480 l2cap_chan_unlock(chan);
1481 }
1482
1483 mutex_unlock(&conn->chan_lock);
1484 }
1485
1486 static void l2cap_le_conn_ready(struct l2cap_conn *conn)
1487 {
1488 struct hci_conn *hcon = conn->hcon;
1489 struct hci_dev *hdev = hcon->hdev;
1490
1491 BT_DBG("%s conn %p", hdev->name, conn);
1492
1493 /* For outgoing pairing which doesn't necessarily have an
1494 * associated socket (e.g. mgmt_pair_device).
1495 */
1496 if (hcon->out)
1497 smp_conn_security(hcon, hcon->pending_sec_level);
1498
1499 /* For LE slave connections, make sure the connection interval
1500 * is in the range of the minium and maximum interval that has
1501 * been configured for this connection. If not, then trigger
1502 * the connection update procedure.
1503 */
1504 if (hcon->role == HCI_ROLE_SLAVE &&
1505 (hcon->le_conn_interval < hcon->le_conn_min_interval ||
1506 hcon->le_conn_interval > hcon->le_conn_max_interval)) {
1507 struct l2cap_conn_param_update_req req;
1508
1509 req.min = cpu_to_le16(hcon->le_conn_min_interval);
1510 req.max = cpu_to_le16(hcon->le_conn_max_interval);
1511 req.latency = cpu_to_le16(hcon->le_conn_latency);
1512 req.to_multiplier = cpu_to_le16(hcon->le_supv_timeout);
1513
1514 l2cap_send_cmd(conn, l2cap_get_ident(conn),
1515 L2CAP_CONN_PARAM_UPDATE_REQ, sizeof(req), &req);
1516 }
1517 }
1518
1519 static void l2cap_conn_ready(struct l2cap_conn *conn)
1520 {
1521 struct l2cap_chan *chan;
1522 struct hci_conn *hcon = conn->hcon;
1523
1524 BT_DBG("conn %p", conn);
1525
1526 if (hcon->type == ACL_LINK)
1527 l2cap_request_info(conn);
1528
1529 mutex_lock(&conn->chan_lock);
1530
1531 list_for_each_entry(chan, &conn->chan_l, list) {
1532
1533 l2cap_chan_lock(chan);
1534
1535 if (chan->scid == L2CAP_CID_A2MP) {
1536 l2cap_chan_unlock(chan);
1537 continue;
1538 }
1539
1540 if (hcon->type == LE_LINK) {
1541 l2cap_le_start(chan);
1542 } else if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) {
1543 if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE)
1544 l2cap_chan_ready(chan);
1545 } else if (chan->state == BT_CONNECT) {
1546 l2cap_do_start(chan);
1547 }
1548
1549 l2cap_chan_unlock(chan);
1550 }
1551
1552 mutex_unlock(&conn->chan_lock);
1553
1554 if (hcon->type == LE_LINK)
1555 l2cap_le_conn_ready(conn);
1556
1557 queue_work(hcon->hdev->workqueue, &conn->pending_rx_work);
1558 }
1559
1560 /* Notify sockets that we cannot guaranty reliability anymore */
1561 static void l2cap_conn_unreliable(struct l2cap_conn *conn, int err)
1562 {
1563 struct l2cap_chan *chan;
1564
1565 BT_DBG("conn %p", conn);
1566
1567 mutex_lock(&conn->chan_lock);
1568
1569 list_for_each_entry(chan, &conn->chan_l, list) {
1570 if (test_bit(FLAG_FORCE_RELIABLE, &chan->flags))
1571 l2cap_chan_set_err(chan, err);
1572 }
1573
1574 mutex_unlock(&conn->chan_lock);
1575 }
1576
1577 static void l2cap_info_timeout(struct work_struct *work)
1578 {
1579 struct l2cap_conn *conn = container_of(work, struct l2cap_conn,
1580 info_timer.work);
1581
1582 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
1583 conn->info_ident = 0;
1584
1585 l2cap_conn_start(conn);
1586 }
1587
1588 /*
1589 * l2cap_user
1590 * External modules can register l2cap_user objects on l2cap_conn. The ->probe
1591 * callback is called during registration. The ->remove callback is called
1592 * during unregistration.
1593 * An l2cap_user object can either be explicitly unregistered or when the
1594 * underlying l2cap_conn object is deleted. This guarantees that l2cap->hcon,
1595 * l2cap->hchan, .. are valid as long as the remove callback hasn't been called.
1596 * External modules must own a reference to the l2cap_conn object if they intend
1597 * to call l2cap_unregister_user(). The l2cap_conn object might get destroyed at
1598 * any time if they don't.
1599 */
1600
1601 int l2cap_register_user(struct l2cap_conn *conn, struct l2cap_user *user)
1602 {
1603 struct hci_dev *hdev = conn->hcon->hdev;
1604 int ret;
1605
1606 /* We need to check whether l2cap_conn is registered. If it is not, we
1607 * must not register the l2cap_user. l2cap_conn_del() is unregisters
1608 * l2cap_conn objects, but doesn't provide its own locking. Instead, it
1609 * relies on the parent hci_conn object to be locked. This itself relies
1610 * on the hci_dev object to be locked. So we must lock the hci device
1611 * here, too. */
1612
1613 hci_dev_lock(hdev);
1614
1615 if (!list_empty(&user->list)) {
1616 ret = -EINVAL;
1617 goto out_unlock;
1618 }
1619
1620 /* conn->hchan is NULL after l2cap_conn_del() was called */
1621 if (!conn->hchan) {
1622 ret = -ENODEV;
1623 goto out_unlock;
1624 }
1625
1626 ret = user->probe(conn, user);
1627 if (ret)
1628 goto out_unlock;
1629
1630 list_add(&user->list, &conn->users);
1631 ret = 0;
1632
1633 out_unlock:
1634 hci_dev_unlock(hdev);
1635 return ret;
1636 }
1637 EXPORT_SYMBOL(l2cap_register_user);
1638
1639 void l2cap_unregister_user(struct l2cap_conn *conn, struct l2cap_user *user)
1640 {
1641 struct hci_dev *hdev = conn->hcon->hdev;
1642
1643 hci_dev_lock(hdev);
1644
1645 if (list_empty(&user->list))
1646 goto out_unlock;
1647
1648 list_del_init(&user->list);
1649 user->remove(conn, user);
1650
1651 out_unlock:
1652 hci_dev_unlock(hdev);
1653 }
1654 EXPORT_SYMBOL(l2cap_unregister_user);
1655
1656 static void l2cap_unregister_all_users(struct l2cap_conn *conn)
1657 {
1658 struct l2cap_user *user;
1659
1660 while (!list_empty(&conn->users)) {
1661 user = list_first_entry(&conn->users, struct l2cap_user, list);
1662 list_del_init(&user->list);
1663 user->remove(conn, user);
1664 }
1665 }
1666
1667 static void l2cap_conn_del(struct hci_conn *hcon, int err)
1668 {
1669 struct l2cap_conn *conn = hcon->l2cap_data;
1670 struct l2cap_chan *chan, *l;
1671
1672 if (!conn)
1673 return;
1674
1675 BT_DBG("hcon %p conn %p, err %d", hcon, conn, err);
1676
1677 kfree_skb(conn->rx_skb);
1678
1679 skb_queue_purge(&conn->pending_rx);
1680
1681 /* We can not call flush_work(&conn->pending_rx_work) here since we
1682 * might block if we are running on a worker from the same workqueue
1683 * pending_rx_work is waiting on.
1684 */
1685 if (work_pending(&conn->pending_rx_work))
1686 cancel_work_sync(&conn->pending_rx_work);
1687
1688 if (work_pending(&conn->id_addr_update_work))
1689 cancel_work_sync(&conn->id_addr_update_work);
1690
1691 l2cap_unregister_all_users(conn);
1692
1693 /* Force the connection to be immediately dropped */
1694 hcon->disc_timeout = 0;
1695
1696 mutex_lock(&conn->chan_lock);
1697
1698 /* Kill channels */
1699 list_for_each_entry_safe(chan, l, &conn->chan_l, list) {
1700 l2cap_chan_hold(chan);
1701 l2cap_chan_lock(chan);
1702
1703 l2cap_chan_del(chan, err);
1704
1705 l2cap_chan_unlock(chan);
1706
1707 chan->ops->close(chan);
1708 l2cap_chan_put(chan);
1709 }
1710
1711 mutex_unlock(&conn->chan_lock);
1712
1713 hci_chan_del(conn->hchan);
1714
1715 if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT)
1716 cancel_delayed_work_sync(&conn->info_timer);
1717
1718 hcon->l2cap_data = NULL;
1719 conn->hchan = NULL;
1720 l2cap_conn_put(conn);
1721 }
1722
1723 static void l2cap_conn_free(struct kref *ref)
1724 {
1725 struct l2cap_conn *conn = container_of(ref, struct l2cap_conn, ref);
1726
1727 hci_conn_put(conn->hcon);
1728 kfree(conn);
1729 }
1730
1731 struct l2cap_conn *l2cap_conn_get(struct l2cap_conn *conn)
1732 {
1733 kref_get(&conn->ref);
1734 return conn;
1735 }
1736 EXPORT_SYMBOL(l2cap_conn_get);
1737
1738 void l2cap_conn_put(struct l2cap_conn *conn)
1739 {
1740 kref_put(&conn->ref, l2cap_conn_free);
1741 }
1742 EXPORT_SYMBOL(l2cap_conn_put);
1743
1744 /* ---- Socket interface ---- */
1745
1746 /* Find socket with psm and source / destination bdaddr.
1747 * Returns closest match.
1748 */
1749 static struct l2cap_chan *l2cap_global_chan_by_psm(int state, __le16 psm,
1750 bdaddr_t *src,
1751 bdaddr_t *dst,
1752 u8 link_type)
1753 {
1754 struct l2cap_chan *c, *c1 = NULL;
1755
1756 read_lock(&chan_list_lock);
1757
1758 list_for_each_entry(c, &chan_list, global_l) {
1759 if (state && c->state != state)
1760 continue;
1761
1762 if (link_type == ACL_LINK && c->src_type != BDADDR_BREDR)
1763 continue;
1764
1765 if (link_type == LE_LINK && c->src_type == BDADDR_BREDR)
1766 continue;
1767
1768 if (c->psm == psm) {
1769 int src_match, dst_match;
1770 int src_any, dst_any;
1771
1772 /* Exact match. */
1773 src_match = !bacmp(&c->src, src);
1774 dst_match = !bacmp(&c->dst, dst);
1775 if (src_match && dst_match) {
1776 l2cap_chan_hold(c);
1777 read_unlock(&chan_list_lock);
1778 return c;
1779 }
1780
1781 /* Closest match */
1782 src_any = !bacmp(&c->src, BDADDR_ANY);
1783 dst_any = !bacmp(&c->dst, BDADDR_ANY);
1784 if ((src_match && dst_any) || (src_any && dst_match) ||
1785 (src_any && dst_any))
1786 c1 = c;
1787 }
1788 }
1789
1790 if (c1)
1791 l2cap_chan_hold(c1);
1792
1793 read_unlock(&chan_list_lock);
1794
1795 return c1;
1796 }
1797
1798 static void l2cap_monitor_timeout(struct work_struct *work)
1799 {
1800 struct l2cap_chan *chan = container_of(work, struct l2cap_chan,
1801 monitor_timer.work);
1802
1803 BT_DBG("chan %p", chan);
1804
1805 l2cap_chan_lock(chan);
1806
1807 if (!chan->conn) {
1808 l2cap_chan_unlock(chan);
1809 l2cap_chan_put(chan);
1810 return;
1811 }
1812
1813 l2cap_tx(chan, NULL, NULL, L2CAP_EV_MONITOR_TO);
1814
1815 l2cap_chan_unlock(chan);
1816 l2cap_chan_put(chan);
1817 }
1818
1819 static void l2cap_retrans_timeout(struct work_struct *work)
1820 {
1821 struct l2cap_chan *chan = container_of(work, struct l2cap_chan,
1822 retrans_timer.work);
1823
1824 BT_DBG("chan %p", chan);
1825
1826 l2cap_chan_lock(chan);
1827
1828 if (!chan->conn) {
1829 l2cap_chan_unlock(chan);
1830 l2cap_chan_put(chan);
1831 return;
1832 }
1833
1834 l2cap_tx(chan, NULL, NULL, L2CAP_EV_RETRANS_TO);
1835 l2cap_chan_unlock(chan);
1836 l2cap_chan_put(chan);
1837 }
1838
1839 static void l2cap_streaming_send(struct l2cap_chan *chan,
1840 struct sk_buff_head *skbs)
1841 {
1842 struct sk_buff *skb;
1843 struct l2cap_ctrl *control;
1844
1845 BT_DBG("chan %p, skbs %p", chan, skbs);
1846
1847 if (__chan_is_moving(chan))
1848 return;
1849
1850 skb_queue_splice_tail_init(skbs, &chan->tx_q);
1851
1852 while (!skb_queue_empty(&chan->tx_q)) {
1853
1854 skb = skb_dequeue(&chan->tx_q);
1855
1856 bt_cb(skb)->l2cap.retries = 1;
1857 control = &bt_cb(skb)->l2cap;
1858
1859 control->reqseq = 0;
1860 control->txseq = chan->next_tx_seq;
1861
1862 __pack_control(chan, control, skb);
1863
1864 if (chan->fcs == L2CAP_FCS_CRC16) {
1865 u16 fcs = crc16(0, (u8 *) skb->data, skb->len);
1866 put_unaligned_le16(fcs, skb_put(skb, L2CAP_FCS_SIZE));
1867 }
1868
1869 l2cap_do_send(chan, skb);
1870
1871 BT_DBG("Sent txseq %u", control->txseq);
1872
1873 chan->next_tx_seq = __next_seq(chan, chan->next_tx_seq);
1874 chan->frames_sent++;
1875 }
1876 }
1877
1878 static int l2cap_ertm_send(struct l2cap_chan *chan)
1879 {
1880 struct sk_buff *skb, *tx_skb;
1881 struct l2cap_ctrl *control;
1882 int sent = 0;
1883
1884 BT_DBG("chan %p", chan);
1885
1886 if (chan->state != BT_CONNECTED)
1887 return -ENOTCONN;
1888
1889 if (test_bit(CONN_REMOTE_BUSY, &chan->conn_state))
1890 return 0;
1891
1892 if (__chan_is_moving(chan))
1893 return 0;
1894
1895 while (chan->tx_send_head &&
1896 chan->unacked_frames < chan->remote_tx_win &&
1897 chan->tx_state == L2CAP_TX_STATE_XMIT) {
1898
1899 skb = chan->tx_send_head;
1900
1901 bt_cb(skb)->l2cap.retries = 1;
1902 control = &bt_cb(skb)->l2cap;
1903
1904 if (test_and_clear_bit(CONN_SEND_FBIT, &chan->conn_state))
1905 control->final = 1;
1906
1907 control->reqseq = chan->buffer_seq;
1908 chan->last_acked_seq = chan->buffer_seq;
1909 control->txseq = chan->next_tx_seq;
1910
1911 __pack_control(chan, control, skb);
1912
1913 if (chan->fcs == L2CAP_FCS_CRC16) {
1914 u16 fcs = crc16(0, (u8 *) skb->data, skb->len);
1915 put_unaligned_le16(fcs, skb_put(skb, L2CAP_FCS_SIZE));
1916 }
1917
1918 /* Clone after data has been modified. Data is assumed to be
1919 read-only (for locking purposes) on cloned sk_buffs.
1920 */
1921 tx_skb = skb_clone(skb, GFP_KERNEL);
1922
1923 if (!tx_skb)
1924 break;
1925
1926 __set_retrans_timer(chan);
1927
1928 chan->next_tx_seq = __next_seq(chan, chan->next_tx_seq);
1929 chan->unacked_frames++;
1930 chan->frames_sent++;
1931 sent++;
1932
1933 if (skb_queue_is_last(&chan->tx_q, skb))
1934 chan->tx_send_head = NULL;
1935 else
1936 chan->tx_send_head = skb_queue_next(&chan->tx_q, skb);
1937
1938 l2cap_do_send(chan, tx_skb);
1939 BT_DBG("Sent txseq %u", control->txseq);
1940 }
1941
1942 BT_DBG("Sent %d, %u unacked, %u in ERTM queue", sent,
1943 chan->unacked_frames, skb_queue_len(&chan->tx_q));
1944
1945 return sent;
1946 }
1947
1948 static void l2cap_ertm_resend(struct l2cap_chan *chan)
1949 {
1950 struct l2cap_ctrl control;
1951 struct sk_buff *skb;
1952 struct sk_buff *tx_skb;
1953 u16 seq;
1954
1955 BT_DBG("chan %p", chan);
1956
1957 if (test_bit(CONN_REMOTE_BUSY, &chan->conn_state))
1958 return;
1959
1960 if (__chan_is_moving(chan))
1961 return;
1962
1963 while (chan->retrans_list.head != L2CAP_SEQ_LIST_CLEAR) {
1964 seq = l2cap_seq_list_pop(&chan->retrans_list);
1965
1966 skb = l2cap_ertm_seq_in_queue(&chan->tx_q, seq);
1967 if (!skb) {
1968 BT_DBG("Error: Can't retransmit seq %d, frame missing",
1969 seq);
1970 continue;
1971 }
1972
1973 bt_cb(skb)->l2cap.retries++;
1974 control = bt_cb(skb)->l2cap;
1975
1976 if (chan->max_tx != 0 &&
1977 bt_cb(skb)->l2cap.retries > chan->max_tx) {
1978 BT_DBG("Retry limit exceeded (%d)", chan->max_tx);
1979 l2cap_send_disconn_req(chan, ECONNRESET);
1980 l2cap_seq_list_clear(&chan->retrans_list);
1981 break;
1982 }
1983
1984 control.reqseq = chan->buffer_seq;
1985 if (test_and_clear_bit(CONN_SEND_FBIT, &chan->conn_state))
1986 control.final = 1;
1987 else
1988 control.final = 0;
1989
1990 if (skb_cloned(skb)) {
1991 /* Cloned sk_buffs are read-only, so we need a
1992 * writeable copy
1993 */
1994 tx_skb = skb_copy(skb, GFP_KERNEL);
1995 } else {
1996 tx_skb = skb_clone(skb, GFP_KERNEL);
1997 }
1998
1999 if (!tx_skb) {
2000 l2cap_seq_list_clear(&chan->retrans_list);
2001 break;
2002 }
2003
2004 /* Update skb contents */
2005 if (test_bit(FLAG_EXT_CTRL, &chan->flags)) {
2006 put_unaligned_le32(__pack_extended_control(&control),
2007 tx_skb->data + L2CAP_HDR_SIZE);
2008 } else {
2009 put_unaligned_le16(__pack_enhanced_control(&control),
2010 tx_skb->data + L2CAP_HDR_SIZE);
2011 }
2012
2013 /* Update FCS */
2014 if (chan->fcs == L2CAP_FCS_CRC16) {
2015 u16 fcs = crc16(0, (u8 *) tx_skb->data,
2016 tx_skb->len - L2CAP_FCS_SIZE);
2017 put_unaligned_le16(fcs, skb_tail_pointer(tx_skb) -
2018 L2CAP_FCS_SIZE);
2019 }
2020
2021 l2cap_do_send(chan, tx_skb);
2022
2023 BT_DBG("Resent txseq %d", control.txseq);
2024
2025 chan->last_acked_seq = chan->buffer_seq;
2026 }
2027 }
2028
2029 static void l2cap_retransmit(struct l2cap_chan *chan,
2030 struct l2cap_ctrl *control)
2031 {
2032 BT_DBG("chan %p, control %p", chan, control);
2033
2034 l2cap_seq_list_append(&chan->retrans_list, control->reqseq);
2035 l2cap_ertm_resend(chan);
2036 }
2037
2038 static void l2cap_retransmit_all(struct l2cap_chan *chan,
2039 struct l2cap_ctrl *control)
2040 {
2041 struct sk_buff *skb;
2042
2043 BT_DBG("chan %p, control %p", chan, control);
2044
2045 if (control->poll)
2046 set_bit(CONN_SEND_FBIT, &chan->conn_state);
2047
2048 l2cap_seq_list_clear(&chan->retrans_list);
2049
2050 if (test_bit(CONN_REMOTE_BUSY, &chan->conn_state))
2051 return;
2052
2053 if (chan->unacked_frames) {
2054 skb_queue_walk(&chan->tx_q, skb) {
2055 if (bt_cb(skb)->l2cap.txseq == control->reqseq ||
2056 skb == chan->tx_send_head)
2057 break;
2058 }
2059
2060 skb_queue_walk_from(&chan->tx_q, skb) {
2061 if (skb == chan->tx_send_head)
2062 break;
2063
2064 l2cap_seq_list_append(&chan->retrans_list,
2065 bt_cb(skb)->l2cap.txseq);
2066 }
2067
2068 l2cap_ertm_resend(chan);
2069 }
2070 }
2071
2072 static void l2cap_send_ack(struct l2cap_chan *chan)
2073 {
2074 struct l2cap_ctrl control;
2075 u16 frames_to_ack = __seq_offset(chan, chan->buffer_seq,
2076 chan->last_acked_seq);
2077 int threshold;
2078
2079 BT_DBG("chan %p last_acked_seq %d buffer_seq %d",
2080 chan, chan->last_acked_seq, chan->buffer_seq);
2081
2082 memset(&control, 0, sizeof(control));
2083 control.sframe = 1;
2084
2085 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state) &&
2086 chan->rx_state == L2CAP_RX_STATE_RECV) {
2087 __clear_ack_timer(chan);
2088 control.super = L2CAP_SUPER_RNR;
2089 control.reqseq = chan->buffer_seq;
2090 l2cap_send_sframe(chan, &control);
2091 } else {
2092 if (!test_bit(CONN_REMOTE_BUSY, &chan->conn_state)) {
2093 l2cap_ertm_send(chan);
2094 /* If any i-frames were sent, they included an ack */
2095 if (chan->buffer_seq == chan->last_acked_seq)
2096 frames_to_ack = 0;
2097 }
2098
2099 /* Ack now if the window is 3/4ths full.
2100 * Calculate without mul or div
2101 */
2102 threshold = chan->ack_win;
2103 threshold += threshold << 1;
2104 threshold >>= 2;
2105
2106 BT_DBG("frames_to_ack %u, threshold %d", frames_to_ack,
2107 threshold);
2108
2109 if (frames_to_ack >= threshold) {
2110 __clear_ack_timer(chan);
2111 control.super = L2CAP_SUPER_RR;
2112 control.reqseq = chan->buffer_seq;
2113 l2cap_send_sframe(chan, &control);
2114 frames_to_ack = 0;
2115 }
2116
2117 if (frames_to_ack)
2118 __set_ack_timer(chan);
2119 }
2120 }
2121
2122 static inline int l2cap_skbuff_fromiovec(struct l2cap_chan *chan,
2123 struct msghdr *msg, int len,
2124 int count, struct sk_buff *skb)
2125 {
2126 struct l2cap_conn *conn = chan->conn;
2127 struct sk_buff **frag;
2128 int sent = 0;
2129
2130 if (copy_from_iter(skb_put(skb, count), count, &msg->msg_iter) != count)
2131 return -EFAULT;
2132
2133 sent += count;
2134 len -= count;
2135
2136 /* Continuation fragments (no L2CAP header) */
2137 frag = &skb_shinfo(skb)->frag_list;
2138 while (len) {
2139 struct sk_buff *tmp;
2140
2141 count = min_t(unsigned int, conn->mtu, len);
2142
2143 tmp = chan->ops->alloc_skb(chan, 0, count,
2144 msg->msg_flags & MSG_DONTWAIT);
2145 if (IS_ERR(tmp))
2146 return PTR_ERR(tmp);
2147
2148 *frag = tmp;
2149
2150 if (copy_from_iter(skb_put(*frag, count), count,
2151 &msg->msg_iter) != count)
2152 return -EFAULT;
2153
2154 sent += count;
2155 len -= count;
2156
2157 skb->len += (*frag)->len;
2158 skb->data_len += (*frag)->len;
2159
2160 frag = &(*frag)->next;
2161 }
2162
2163 return sent;
2164 }
2165
2166 static struct sk_buff *l2cap_create_connless_pdu(struct l2cap_chan *chan,
2167 struct msghdr *msg, size_t len)
2168 {
2169 struct l2cap_conn *conn = chan->conn;
2170 struct sk_buff *skb;
2171 int err, count, hlen = L2CAP_HDR_SIZE + L2CAP_PSMLEN_SIZE;
2172 struct l2cap_hdr *lh;
2173
2174 BT_DBG("chan %p psm 0x%2.2x len %zu", chan,
2175 __le16_to_cpu(chan->psm), len);
2176
2177 count = min_t(unsigned int, (conn->mtu - hlen), len);
2178
2179 skb = chan->ops->alloc_skb(chan, hlen, count,
2180 msg->msg_flags & MSG_DONTWAIT);
2181 if (IS_ERR(skb))
2182 return skb;
2183
2184 /* Create L2CAP header */
2185 lh = (struct l2cap_hdr *) skb_put(skb, L2CAP_HDR_SIZE);
2186 lh->cid = cpu_to_le16(chan->dcid);
2187 lh->len = cpu_to_le16(len + L2CAP_PSMLEN_SIZE);
2188 put_unaligned(chan->psm, (__le16 *) skb_put(skb, L2CAP_PSMLEN_SIZE));
2189
2190 err = l2cap_skbuff_fromiovec(chan, msg, len, count, skb);
2191 if (unlikely(err < 0)) {
2192 kfree_skb(skb);
2193 return ERR_PTR(err);
2194 }
2195 return skb;
2196 }
2197
2198 static struct sk_buff *l2cap_create_basic_pdu(struct l2cap_chan *chan,
2199 struct msghdr *msg, size_t len)
2200 {
2201 struct l2cap_conn *conn = chan->conn;
2202 struct sk_buff *skb;
2203 int err, count;
2204 struct l2cap_hdr *lh;
2205
2206 BT_DBG("chan %p len %zu", chan, len);
2207
2208 count = min_t(unsigned int, (conn->mtu - L2CAP_HDR_SIZE), len);
2209
2210 skb = chan->ops->alloc_skb(chan, L2CAP_HDR_SIZE, count,
2211 msg->msg_flags & MSG_DONTWAIT);
2212 if (IS_ERR(skb))
2213 return skb;
2214
2215 /* Create L2CAP header */
2216 lh = (struct l2cap_hdr *) skb_put(skb, L2CAP_HDR_SIZE);
2217 lh->cid = cpu_to_le16(chan->dcid);
2218 lh->len = cpu_to_le16(len);
2219
2220 err = l2cap_skbuff_fromiovec(chan, msg, len, count, skb);
2221 if (unlikely(err < 0)) {
2222 kfree_skb(skb);
2223 return ERR_PTR(err);
2224 }
2225 return skb;
2226 }
2227
2228 static struct sk_buff *l2cap_create_iframe_pdu(struct l2cap_chan *chan,
2229 struct msghdr *msg, size_t len,
2230 u16 sdulen)
2231 {
2232 struct l2cap_conn *conn = chan->conn;
2233 struct sk_buff *skb;
2234 int err, count, hlen;
2235 struct l2cap_hdr *lh;
2236
2237 BT_DBG("chan %p len %zu", chan, len);
2238
2239 if (!conn)
2240 return ERR_PTR(-ENOTCONN);
2241
2242 hlen = __ertm_hdr_size(chan);
2243
2244 if (sdulen)
2245 hlen += L2CAP_SDULEN_SIZE;
2246
2247 if (chan->fcs == L2CAP_FCS_CRC16)
2248 hlen += L2CAP_FCS_SIZE;
2249
2250 count = min_t(unsigned int, (conn->mtu - hlen), len);
2251
2252 skb = chan->ops->alloc_skb(chan, hlen, count,
2253 msg->msg_flags & MSG_DONTWAIT);
2254 if (IS_ERR(skb))
2255 return skb;
2256
2257 /* Create L2CAP header */
2258 lh = (struct l2cap_hdr *) skb_put(skb, L2CAP_HDR_SIZE);
2259 lh->cid = cpu_to_le16(chan->dcid);
2260 lh->len = cpu_to_le16(len + (hlen - L2CAP_HDR_SIZE));
2261
2262 /* Control header is populated later */
2263 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
2264 put_unaligned_le32(0, skb_put(skb, L2CAP_EXT_CTRL_SIZE));
2265 else
2266 put_unaligned_le16(0, skb_put(skb, L2CAP_ENH_CTRL_SIZE));
2267
2268 if (sdulen)
2269 put_unaligned_le16(sdulen, skb_put(skb, L2CAP_SDULEN_SIZE));
2270
2271 err = l2cap_skbuff_fromiovec(chan, msg, len, count, skb);
2272 if (unlikely(err < 0)) {
2273 kfree_skb(skb);
2274 return ERR_PTR(err);
2275 }
2276
2277 bt_cb(skb)->l2cap.fcs = chan->fcs;
2278 bt_cb(skb)->l2cap.retries = 0;
2279 return skb;
2280 }
2281
2282 static int l2cap_segment_sdu(struct l2cap_chan *chan,
2283 struct sk_buff_head *seg_queue,
2284 struct msghdr *msg, size_t len)
2285 {
2286 struct sk_buff *skb;
2287 u16 sdu_len;
2288 size_t pdu_len;
2289 u8 sar;
2290
2291 BT_DBG("chan %p, msg %p, len %zu", chan, msg, len);
2292
2293 /* It is critical that ERTM PDUs fit in a single HCI fragment,
2294 * so fragmented skbs are not used. The HCI layer's handling
2295 * of fragmented skbs is not compatible with ERTM's queueing.
2296 */
2297
2298 /* PDU size is derived from the HCI MTU */
2299 pdu_len = chan->conn->mtu;
2300
2301 /* Constrain PDU size for BR/EDR connections */
2302 if (!chan->hs_hcon)
2303 pdu_len = min_t(size_t, pdu_len, L2CAP_BREDR_MAX_PAYLOAD);
2304
2305 /* Adjust for largest possible L2CAP overhead. */
2306 if (chan->fcs)
2307 pdu_len -= L2CAP_FCS_SIZE;
2308
2309 pdu_len -= __ertm_hdr_size(chan);
2310
2311 /* Remote device may have requested smaller PDUs */
2312 pdu_len = min_t(size_t, pdu_len, chan->remote_mps);
2313
2314 if (len <= pdu_len) {
2315 sar = L2CAP_SAR_UNSEGMENTED;
2316 sdu_len = 0;
2317 pdu_len = len;
2318 } else {
2319 sar = L2CAP_SAR_START;
2320 sdu_len = len;
2321 }
2322
2323 while (len > 0) {
2324 skb = l2cap_create_iframe_pdu(chan, msg, pdu_len, sdu_len);
2325
2326 if (IS_ERR(skb)) {
2327 __skb_queue_purge(seg_queue);
2328 return PTR_ERR(skb);
2329 }
2330
2331 bt_cb(skb)->l2cap.sar = sar;
2332 __skb_queue_tail(seg_queue, skb);
2333
2334 len -= pdu_len;
2335 if (sdu_len)
2336 sdu_len = 0;
2337
2338 if (len <= pdu_len) {
2339 sar = L2CAP_SAR_END;
2340 pdu_len = len;
2341 } else {
2342 sar = L2CAP_SAR_CONTINUE;
2343 }
2344 }
2345
2346 return 0;
2347 }
2348
2349 static struct sk_buff *l2cap_create_le_flowctl_pdu(struct l2cap_chan *chan,
2350 struct msghdr *msg,
2351 size_t len, u16 sdulen)
2352 {
2353 struct l2cap_conn *conn = chan->conn;
2354 struct sk_buff *skb;
2355 int err, count, hlen;
2356 struct l2cap_hdr *lh;
2357
2358 BT_DBG("chan %p len %zu", chan, len);
2359
2360 if (!conn)
2361 return ERR_PTR(-ENOTCONN);
2362
2363 hlen = L2CAP_HDR_SIZE;
2364
2365 if (sdulen)
2366 hlen += L2CAP_SDULEN_SIZE;
2367
2368 count = min_t(unsigned int, (conn->mtu - hlen), len);
2369
2370 skb = chan->ops->alloc_skb(chan, hlen, count,
2371 msg->msg_flags & MSG_DONTWAIT);
2372 if (IS_ERR(skb))
2373 return skb;
2374
2375 /* Create L2CAP header */
2376 lh = (struct l2cap_hdr *) skb_put(skb, L2CAP_HDR_SIZE);
2377 lh->cid = cpu_to_le16(chan->dcid);
2378 lh->len = cpu_to_le16(len + (hlen - L2CAP_HDR_SIZE));
2379
2380 if (sdulen)
2381 put_unaligned_le16(sdulen, skb_put(skb, L2CAP_SDULEN_SIZE));
2382
2383 err = l2cap_skbuff_fromiovec(chan, msg, len, count, skb);
2384 if (unlikely(err < 0)) {
2385 kfree_skb(skb);
2386 return ERR_PTR(err);
2387 }
2388
2389 return skb;
2390 }
2391
2392 static int l2cap_segment_le_sdu(struct l2cap_chan *chan,
2393 struct sk_buff_head *seg_queue,
2394 struct msghdr *msg, size_t len)
2395 {
2396 struct sk_buff *skb;
2397 size_t pdu_len;
2398 u16 sdu_len;
2399
2400 BT_DBG("chan %p, msg %p, len %zu", chan, msg, len);
2401
2402 sdu_len = len;
2403 pdu_len = chan->remote_mps - L2CAP_SDULEN_SIZE;
2404
2405 while (len > 0) {
2406 if (len <= pdu_len)
2407 pdu_len = len;
2408
2409 skb = l2cap_create_le_flowctl_pdu(chan, msg, pdu_len, sdu_len);
2410 if (IS_ERR(skb)) {
2411 __skb_queue_purge(seg_queue);
2412 return PTR_ERR(skb);
2413 }
2414
2415 __skb_queue_tail(seg_queue, skb);
2416
2417 len -= pdu_len;
2418
2419 if (sdu_len) {
2420 sdu_len = 0;
2421 pdu_len += L2CAP_SDULEN_SIZE;
2422 }
2423 }
2424
2425 return 0;
2426 }
2427
2428 int l2cap_chan_send(struct l2cap_chan *chan, struct msghdr *msg, size_t len)
2429 {
2430 struct sk_buff *skb;
2431 int err;
2432 struct sk_buff_head seg_queue;
2433
2434 if (!chan->conn)
2435 return -ENOTCONN;
2436
2437 /* Connectionless channel */
2438 if (chan->chan_type == L2CAP_CHAN_CONN_LESS) {
2439 skb = l2cap_create_connless_pdu(chan, msg, len);
2440 if (IS_ERR(skb))
2441 return PTR_ERR(skb);
2442
2443 /* Channel lock is released before requesting new skb and then
2444 * reacquired thus we need to recheck channel state.
2445 */
2446 if (chan->state != BT_CONNECTED) {
2447 kfree_skb(skb);
2448 return -ENOTCONN;
2449 }
2450
2451 l2cap_do_send(chan, skb);
2452 return len;
2453 }
2454
2455 switch (chan->mode) {
2456 case L2CAP_MODE_LE_FLOWCTL:
2457 /* Check outgoing MTU */
2458 if (len > chan->omtu)
2459 return -EMSGSIZE;
2460
2461 if (!chan->tx_credits)
2462 return -EAGAIN;
2463
2464 __skb_queue_head_init(&seg_queue);
2465
2466 err = l2cap_segment_le_sdu(chan, &seg_queue, msg, len);
2467
2468 if (chan->state != BT_CONNECTED) {
2469 __skb_queue_purge(&seg_queue);
2470 err = -ENOTCONN;
2471 }
2472
2473 if (err)
2474 return err;
2475
2476 skb_queue_splice_tail_init(&seg_queue, &chan->tx_q);
2477
2478 while (chan->tx_credits && !skb_queue_empty(&chan->tx_q)) {
2479 l2cap_do_send(chan, skb_dequeue(&chan->tx_q));
2480 chan->tx_credits--;
2481 }
2482
2483 if (!chan->tx_credits)
2484 chan->ops->suspend(chan);
2485
2486 err = len;
2487
2488 break;
2489
2490 case L2CAP_MODE_BASIC:
2491 /* Check outgoing MTU */
2492 if (len > chan->omtu)
2493 return -EMSGSIZE;
2494
2495 /* Create a basic PDU */
2496 skb = l2cap_create_basic_pdu(chan, msg, len);
2497 if (IS_ERR(skb))
2498 return PTR_ERR(skb);
2499
2500 /* Channel lock is released before requesting new skb and then
2501 * reacquired thus we need to recheck channel state.
2502 */
2503 if (chan->state != BT_CONNECTED) {
2504 kfree_skb(skb);
2505 return -ENOTCONN;
2506 }
2507
2508 l2cap_do_send(chan, skb);
2509 err = len;
2510 break;
2511
2512 case L2CAP_MODE_ERTM:
2513 case L2CAP_MODE_STREAMING:
2514 /* Check outgoing MTU */
2515 if (len > chan->omtu) {
2516 err = -EMSGSIZE;
2517 break;
2518 }
2519
2520 __skb_queue_head_init(&seg_queue);
2521
2522 /* Do segmentation before calling in to the state machine,
2523 * since it's possible to block while waiting for memory
2524 * allocation.
2525 */
2526 err = l2cap_segment_sdu(chan, &seg_queue, msg, len);
2527
2528 /* The channel could have been closed while segmenting,
2529 * check that it is still connected.
2530 */
2531 if (chan->state != BT_CONNECTED) {
2532 __skb_queue_purge(&seg_queue);
2533 err = -ENOTCONN;
2534 }
2535
2536 if (err)
2537 break;
2538
2539 if (chan->mode == L2CAP_MODE_ERTM)
2540 l2cap_tx(chan, NULL, &seg_queue, L2CAP_EV_DATA_REQUEST);
2541 else
2542 l2cap_streaming_send(chan, &seg_queue);
2543
2544 err = len;
2545
2546 /* If the skbs were not queued for sending, they'll still be in
2547 * seg_queue and need to be purged.
2548 */
2549 __skb_queue_purge(&seg_queue);
2550 break;
2551
2552 default:
2553 BT_DBG("bad state %1.1x", chan->mode);
2554 err = -EBADFD;
2555 }
2556
2557 return err;
2558 }
2559 EXPORT_SYMBOL_GPL(l2cap_chan_send);
2560
2561 static void l2cap_send_srej(struct l2cap_chan *chan, u16 txseq)
2562 {
2563 struct l2cap_ctrl control;
2564 u16 seq;
2565
2566 BT_DBG("chan %p, txseq %u", chan, txseq);
2567
2568 memset(&control, 0, sizeof(control));
2569 control.sframe = 1;
2570 control.super = L2CAP_SUPER_SREJ;
2571
2572 for (seq = chan->expected_tx_seq; seq != txseq;
2573 seq = __next_seq(chan, seq)) {
2574 if (!l2cap_ertm_seq_in_queue(&chan->srej_q, seq)) {
2575 control.reqseq = seq;
2576 l2cap_send_sframe(chan, &control);
2577 l2cap_seq_list_append(&chan->srej_list, seq);
2578 }
2579 }
2580
2581 chan->expected_tx_seq = __next_seq(chan, txseq);
2582 }
2583
2584 static void l2cap_send_srej_tail(struct l2cap_chan *chan)
2585 {
2586 struct l2cap_ctrl control;
2587
2588 BT_DBG("chan %p", chan);
2589
2590 if (chan->srej_list.tail == L2CAP_SEQ_LIST_CLEAR)
2591 return;
2592
2593 memset(&control, 0, sizeof(control));
2594 control.sframe = 1;
2595 control.super = L2CAP_SUPER_SREJ;
2596 control.reqseq = chan->srej_list.tail;
2597 l2cap_send_sframe(chan, &control);
2598 }
2599
2600 static void l2cap_send_srej_list(struct l2cap_chan *chan, u16 txseq)
2601 {
2602 struct l2cap_ctrl control;
2603 u16 initial_head;
2604 u16 seq;
2605
2606 BT_DBG("chan %p, txseq %u", chan, txseq);
2607
2608 memset(&control, 0, sizeof(control));
2609 control.sframe = 1;
2610 control.super = L2CAP_SUPER_SREJ;
2611
2612 /* Capture initial list head to allow only one pass through the list. */
2613 initial_head = chan->srej_list.head;
2614
2615 do {
2616 seq = l2cap_seq_list_pop(&chan->srej_list);
2617 if (seq == txseq || seq == L2CAP_SEQ_LIST_CLEAR)
2618 break;
2619
2620 control.reqseq = seq;
2621 l2cap_send_sframe(chan, &control);
2622 l2cap_seq_list_append(&chan->srej_list, seq);
2623 } while (chan->srej_list.head != initial_head);
2624 }
2625
2626 static void l2cap_process_reqseq(struct l2cap_chan *chan, u16 reqseq)
2627 {
2628 struct sk_buff *acked_skb;
2629 u16 ackseq;
2630
2631 BT_DBG("chan %p, reqseq %u", chan, reqseq);
2632
2633 if (chan->unacked_frames == 0 || reqseq == chan->expected_ack_seq)
2634 return;
2635
2636 BT_DBG("expected_ack_seq %u, unacked_frames %u",
2637 chan->expected_ack_seq, chan->unacked_frames);
2638
2639 for (ackseq = chan->expected_ack_seq; ackseq != reqseq;
2640 ackseq = __next_seq(chan, ackseq)) {
2641
2642 acked_skb = l2cap_ertm_seq_in_queue(&chan->tx_q, ackseq);
2643 if (acked_skb) {
2644 skb_unlink(acked_skb, &chan->tx_q);
2645 kfree_skb(acked_skb);
2646 chan->unacked_frames--;
2647 }
2648 }
2649
2650 chan->expected_ack_seq = reqseq;
2651
2652 if (chan->unacked_frames == 0)
2653 __clear_retrans_timer(chan);
2654
2655 BT_DBG("unacked_frames %u", chan->unacked_frames);
2656 }
2657
2658 static void l2cap_abort_rx_srej_sent(struct l2cap_chan *chan)
2659 {
2660 BT_DBG("chan %p", chan);
2661
2662 chan->expected_tx_seq = chan->buffer_seq;
2663 l2cap_seq_list_clear(&chan->srej_list);
2664 skb_queue_purge(&chan->srej_q);
2665 chan->rx_state = L2CAP_RX_STATE_RECV;
2666 }
2667
2668 static void l2cap_tx_state_xmit(struct l2cap_chan *chan,
2669 struct l2cap_ctrl *control,
2670 struct sk_buff_head *skbs, u8 event)
2671 {
2672 BT_DBG("chan %p, control %p, skbs %p, event %d", chan, control, skbs,
2673 event);
2674
2675 switch (event) {
2676 case L2CAP_EV_DATA_REQUEST:
2677 if (chan->tx_send_head == NULL)
2678 chan->tx_send_head = skb_peek(skbs);
2679
2680 skb_queue_splice_tail_init(skbs, &chan->tx_q);
2681 l2cap_ertm_send(chan);
2682 break;
2683 case L2CAP_EV_LOCAL_BUSY_DETECTED:
2684 BT_DBG("Enter LOCAL_BUSY");
2685 set_bit(CONN_LOCAL_BUSY, &chan->conn_state);
2686
2687 if (chan->rx_state == L2CAP_RX_STATE_SREJ_SENT) {
2688 /* The SREJ_SENT state must be aborted if we are to
2689 * enter the LOCAL_BUSY state.
2690 */
2691 l2cap_abort_rx_srej_sent(chan);
2692 }
2693
2694 l2cap_send_ack(chan);
2695
2696 break;
2697 case L2CAP_EV_LOCAL_BUSY_CLEAR:
2698 BT_DBG("Exit LOCAL_BUSY");
2699 clear_bit(CONN_LOCAL_BUSY, &chan->conn_state);
2700
2701 if (test_bit(CONN_RNR_SENT, &chan->conn_state)) {
2702 struct l2cap_ctrl local_control;
2703
2704 memset(&local_control, 0, sizeof(local_control));
2705 local_control.sframe = 1;
2706 local_control.super = L2CAP_SUPER_RR;
2707 local_control.poll = 1;
2708 local_control.reqseq = chan->buffer_seq;
2709 l2cap_send_sframe(chan, &local_control);
2710
2711 chan->retry_count = 1;
2712 __set_monitor_timer(chan);
2713 chan->tx_state = L2CAP_TX_STATE_WAIT_F;
2714 }
2715 break;
2716 case L2CAP_EV_RECV_REQSEQ_AND_FBIT:
2717 l2cap_process_reqseq(chan, control->reqseq);
2718 break;
2719 case L2CAP_EV_EXPLICIT_POLL:
2720 l2cap_send_rr_or_rnr(chan, 1);
2721 chan->retry_count = 1;
2722 __set_monitor_timer(chan);
2723 __clear_ack_timer(chan);
2724 chan->tx_state = L2CAP_TX_STATE_WAIT_F;
2725 break;
2726 case L2CAP_EV_RETRANS_TO:
2727 l2cap_send_rr_or_rnr(chan, 1);
2728 chan->retry_count = 1;
2729 __set_monitor_timer(chan);
2730 chan->tx_state = L2CAP_TX_STATE_WAIT_F;
2731 break;
2732 case L2CAP_EV_RECV_FBIT:
2733 /* Nothing to process */
2734 break;
2735 default:
2736 break;
2737 }
2738 }
2739
2740 static void l2cap_tx_state_wait_f(struct l2cap_chan *chan,
2741 struct l2cap_ctrl *control,
2742 struct sk_buff_head *skbs, u8 event)
2743 {
2744 BT_DBG("chan %p, control %p, skbs %p, event %d", chan, control, skbs,
2745 event);
2746
2747 switch (event) {
2748 case L2CAP_EV_DATA_REQUEST:
2749 if (chan->tx_send_head == NULL)
2750 chan->tx_send_head = skb_peek(skbs);
2751 /* Queue data, but don't send. */
2752 skb_queue_splice_tail_init(skbs, &chan->tx_q);
2753 break;
2754 case L2CAP_EV_LOCAL_BUSY_DETECTED:
2755 BT_DBG("Enter LOCAL_BUSY");
2756 set_bit(CONN_LOCAL_BUSY, &chan->conn_state);
2757
2758 if (chan->rx_state == L2CAP_RX_STATE_SREJ_SENT) {
2759 /* The SREJ_SENT state must be aborted if we are to
2760 * enter the LOCAL_BUSY state.
2761 */
2762 l2cap_abort_rx_srej_sent(chan);
2763 }
2764
2765 l2cap_send_ack(chan);
2766
2767 break;
2768 case L2CAP_EV_LOCAL_BUSY_CLEAR:
2769 BT_DBG("Exit LOCAL_BUSY");
2770 clear_bit(CONN_LOCAL_BUSY, &chan->conn_state);
2771
2772 if (test_bit(CONN_RNR_SENT, &chan->conn_state)) {
2773 struct l2cap_ctrl local_control;
2774 memset(&local_control, 0, sizeof(local_control));
2775 local_control.sframe = 1;
2776 local_control.super = L2CAP_SUPER_RR;
2777 local_control.poll = 1;
2778 local_control.reqseq = chan->buffer_seq;
2779 l2cap_send_sframe(chan, &local_control);
2780
2781 chan->retry_count = 1;
2782 __set_monitor_timer(chan);
2783 chan->tx_state = L2CAP_TX_STATE_WAIT_F;
2784 }
2785 break;
2786 case L2CAP_EV_RECV_REQSEQ_AND_FBIT:
2787 l2cap_process_reqseq(chan, control->reqseq);
2788
2789 /* Fall through */
2790
2791 case L2CAP_EV_RECV_FBIT:
2792 if (control && control->final) {
2793 __clear_monitor_timer(chan);
2794 if (chan->unacked_frames > 0)
2795 __set_retrans_timer(chan);
2796 chan->retry_count = 0;
2797 chan->tx_state = L2CAP_TX_STATE_XMIT;
2798 BT_DBG("recv fbit tx_state 0x2.2%x", chan->tx_state);
2799 }
2800 break;
2801 case L2CAP_EV_EXPLICIT_POLL:
2802 /* Ignore */
2803 break;
2804 case L2CAP_EV_MONITOR_TO:
2805 if (chan->max_tx == 0 || chan->retry_count < chan->max_tx) {
2806 l2cap_send_rr_or_rnr(chan, 1);
2807 __set_monitor_timer(chan);
2808 chan->retry_count++;
2809 } else {
2810 l2cap_send_disconn_req(chan, ECONNABORTED);
2811 }
2812 break;
2813 default:
2814 break;
2815 }
2816 }
2817
2818 static void l2cap_tx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
2819 struct sk_buff_head *skbs, u8 event)
2820 {
2821 BT_DBG("chan %p, control %p, skbs %p, event %d, state %d",
2822 chan, control, skbs, event, chan->tx_state);
2823
2824 switch (chan->tx_state) {
2825 case L2CAP_TX_STATE_XMIT:
2826 l2cap_tx_state_xmit(chan, control, skbs, event);
2827 break;
2828 case L2CAP_TX_STATE_WAIT_F:
2829 l2cap_tx_state_wait_f(chan, control, skbs, event);
2830 break;
2831 default:
2832 /* Ignore event */
2833 break;
2834 }
2835 }
2836
2837 static void l2cap_pass_to_tx(struct l2cap_chan *chan,
2838 struct l2cap_ctrl *control)
2839 {
2840 BT_DBG("chan %p, control %p", chan, control);
2841 l2cap_tx(chan, control, NULL, L2CAP_EV_RECV_REQSEQ_AND_FBIT);
2842 }
2843
2844 static void l2cap_pass_to_tx_fbit(struct l2cap_chan *chan,
2845 struct l2cap_ctrl *control)
2846 {
2847 BT_DBG("chan %p, control %p", chan, control);
2848 l2cap_tx(chan, control, NULL, L2CAP_EV_RECV_FBIT);
2849 }
2850
2851 /* Copy frame to all raw sockets on that connection */
2852 static void l2cap_raw_recv(struct l2cap_conn *conn, struct sk_buff *skb)
2853 {
2854 struct sk_buff *nskb;
2855 struct l2cap_chan *chan;
2856
2857 BT_DBG("conn %p", conn);
2858
2859 mutex_lock(&conn->chan_lock);
2860
2861 list_for_each_entry(chan, &conn->chan_l, list) {
2862 if (chan->chan_type != L2CAP_CHAN_RAW)
2863 continue;
2864
2865 /* Don't send frame to the channel it came from */
2866 if (bt_cb(skb)->l2cap.chan == chan)
2867 continue;
2868
2869 nskb = skb_clone(skb, GFP_KERNEL);
2870 if (!nskb)
2871 continue;
2872 if (chan->ops->recv(chan, nskb))
2873 kfree_skb(nskb);
2874 }
2875
2876 mutex_unlock(&conn->chan_lock);
2877 }
2878
2879 /* ---- L2CAP signalling commands ---- */
2880 static struct sk_buff *l2cap_build_cmd(struct l2cap_conn *conn, u8 code,
2881 u8 ident, u16 dlen, void *data)
2882 {
2883 struct sk_buff *skb, **frag;
2884 struct l2cap_cmd_hdr *cmd;
2885 struct l2cap_hdr *lh;
2886 int len, count;
2887
2888 BT_DBG("conn %p, code 0x%2.2x, ident 0x%2.2x, len %u",
2889 conn, code, ident, dlen);
2890
2891 if (conn->mtu < L2CAP_HDR_SIZE + L2CAP_CMD_HDR_SIZE)
2892 return NULL;
2893
2894 len = L2CAP_HDR_SIZE + L2CAP_CMD_HDR_SIZE + dlen;
2895 count = min_t(unsigned int, conn->mtu, len);
2896
2897 skb = bt_skb_alloc(count, GFP_KERNEL);
2898 if (!skb)
2899 return NULL;
2900
2901 lh = (struct l2cap_hdr *) skb_put(skb, L2CAP_HDR_SIZE);
2902 lh->len = cpu_to_le16(L2CAP_CMD_HDR_SIZE + dlen);
2903
2904 if (conn->hcon->type == LE_LINK)
2905 lh->cid = cpu_to_le16(L2CAP_CID_LE_SIGNALING);
2906 else
2907 lh->cid = cpu_to_le16(L2CAP_CID_SIGNALING);
2908
2909 cmd = (struct l2cap_cmd_hdr *) skb_put(skb, L2CAP_CMD_HDR_SIZE);
2910 cmd->code = code;
2911 cmd->ident = ident;
2912 cmd->len = cpu_to_le16(dlen);
2913
2914 if (dlen) {
2915 count -= L2CAP_HDR_SIZE + L2CAP_CMD_HDR_SIZE;
2916 memcpy(skb_put(skb, count), data, count);
2917 data += count;
2918 }
2919
2920 len -= skb->len;
2921
2922 /* Continuation fragments (no L2CAP header) */
2923 frag = &skb_shinfo(skb)->frag_list;
2924 while (len) {
2925 count = min_t(unsigned int, conn->mtu, len);
2926
2927 *frag = bt_skb_alloc(count, GFP_KERNEL);
2928 if (!*frag)
2929 goto fail;
2930
2931 memcpy(skb_put(*frag, count), data, count);
2932
2933 len -= count;
2934 data += count;
2935
2936 frag = &(*frag)->next;
2937 }
2938
2939 return skb;
2940
2941 fail:
2942 kfree_skb(skb);
2943 return NULL;
2944 }
2945
2946 static inline int l2cap_get_conf_opt(void **ptr, int *type, int *olen,
2947 unsigned long *val)
2948 {
2949 struct l2cap_conf_opt *opt = *ptr;
2950 int len;
2951
2952 len = L2CAP_CONF_OPT_SIZE + opt->len;
2953 *ptr += len;
2954
2955 *type = opt->type;
2956 *olen = opt->len;
2957
2958 switch (opt->len) {
2959 case 1:
2960 *val = *((u8 *) opt->val);
2961 break;
2962
2963 case 2:
2964 *val = get_unaligned_le16(opt->val);
2965 break;
2966
2967 case 4:
2968 *val = get_unaligned_le32(opt->val);
2969 break;
2970
2971 default:
2972 *val = (unsigned long) opt->val;
2973 break;
2974 }
2975
2976 BT_DBG("type 0x%2.2x len %u val 0x%lx", *type, opt->len, *val);
2977 return len;
2978 }
2979
2980 static void l2cap_add_conf_opt(void **ptr, u8 type, u8 len, unsigned long val)
2981 {
2982 struct l2cap_conf_opt *opt = *ptr;
2983
2984 BT_DBG("type 0x%2.2x len %u val 0x%lx", type, len, val);
2985
2986 opt->type = type;
2987 opt->len = len;
2988
2989 switch (len) {
2990 case 1:
2991 *((u8 *) opt->val) = val;
2992 break;
2993
2994 case 2:
2995 put_unaligned_le16(val, opt->val);
2996 break;
2997
2998 case 4:
2999 put_unaligned_le32(val, opt->val);
3000 break;
3001
3002 default:
3003 memcpy(opt->val, (void *) val, len);
3004 break;
3005 }
3006
3007 *ptr += L2CAP_CONF_OPT_SIZE + len;
3008 }
3009
3010 static void l2cap_add_opt_efs(void **ptr, struct l2cap_chan *chan)
3011 {
3012 struct l2cap_conf_efs efs;
3013
3014 switch (chan->mode) {
3015 case L2CAP_MODE_ERTM:
3016 efs.id = chan->local_id;
3017 efs.stype = chan->local_stype;
3018 efs.msdu = cpu_to_le16(chan->local_msdu);
3019 efs.sdu_itime = cpu_to_le32(chan->local_sdu_itime);
3020 efs.acc_lat = cpu_to_le32(L2CAP_DEFAULT_ACC_LAT);
3021 efs.flush_to = cpu_to_le32(L2CAP_EFS_DEFAULT_FLUSH_TO);
3022 break;
3023
3024 case L2CAP_MODE_STREAMING:
3025 efs.id = 1;
3026 efs.stype = L2CAP_SERV_BESTEFFORT;
3027 efs.msdu = cpu_to_le16(chan->local_msdu);
3028 efs.sdu_itime = cpu_to_le32(chan->local_sdu_itime);
3029 efs.acc_lat = 0;
3030 efs.flush_to = 0;
3031 break;
3032
3033 default:
3034 return;
3035 }
3036
3037 l2cap_add_conf_opt(ptr, L2CAP_CONF_EFS, sizeof(efs),
3038 (unsigned long) &efs);
3039 }
3040
3041 static void l2cap_ack_timeout(struct work_struct *work)
3042 {
3043 struct l2cap_chan *chan = container_of(work, struct l2cap_chan,
3044 ack_timer.work);
3045 u16 frames_to_ack;
3046
3047 BT_DBG("chan %p", chan);
3048
3049 l2cap_chan_lock(chan);
3050
3051 frames_to_ack = __seq_offset(chan, chan->buffer_seq,
3052 chan->last_acked_seq);
3053
3054 if (frames_to_ack)
3055 l2cap_send_rr_or_rnr(chan, 0);
3056
3057 l2cap_chan_unlock(chan);
3058 l2cap_chan_put(chan);
3059 }
3060
3061 int l2cap_ertm_init(struct l2cap_chan *chan)
3062 {
3063 int err;
3064
3065 chan->next_tx_seq = 0;
3066 chan->expected_tx_seq = 0;
3067 chan->expected_ack_seq = 0;
3068 chan->unacked_frames = 0;
3069 chan->buffer_seq = 0;
3070 chan->frames_sent = 0;
3071 chan->last_acked_seq = 0;
3072 chan->sdu = NULL;
3073 chan->sdu_last_frag = NULL;
3074 chan->sdu_len = 0;
3075
3076 skb_queue_head_init(&chan->tx_q);
3077
3078 chan->local_amp_id = AMP_ID_BREDR;
3079 chan->move_id = AMP_ID_BREDR;
3080 chan->move_state = L2CAP_MOVE_STABLE;
3081 chan->move_role = L2CAP_MOVE_ROLE_NONE;
3082
3083 if (chan->mode != L2CAP_MODE_ERTM)
3084 return 0;
3085
3086 chan->rx_state = L2CAP_RX_STATE_RECV;
3087 chan->tx_state = L2CAP_TX_STATE_XMIT;
3088
3089 INIT_DELAYED_WORK(&chan->retrans_timer, l2cap_retrans_timeout);
3090 INIT_DELAYED_WORK(&chan->monitor_timer, l2cap_monitor_timeout);
3091 INIT_DELAYED_WORK(&chan->ack_timer, l2cap_ack_timeout);
3092
3093 skb_queue_head_init(&chan->srej_q);
3094
3095 err = l2cap_seq_list_init(&chan->srej_list, chan->tx_win);
3096 if (err < 0)
3097 return err;
3098
3099 err = l2cap_seq_list_init(&chan->retrans_list, chan->remote_tx_win);
3100 if (err < 0)
3101 l2cap_seq_list_free(&chan->srej_list);
3102
3103 return err;
3104 }
3105
3106 static inline __u8 l2cap_select_mode(__u8 mode, __u16 remote_feat_mask)
3107 {
3108 switch (mode) {
3109 case L2CAP_MODE_STREAMING:
3110 case L2CAP_MODE_ERTM:
3111 if (l2cap_mode_supported(mode, remote_feat_mask))
3112 return mode;
3113 /* fall through */
3114 default:
3115 return L2CAP_MODE_BASIC;
3116 }
3117 }
3118
3119 static inline bool __l2cap_ews_supported(struct l2cap_conn *conn)
3120 {
3121 return ((conn->local_fixed_chan & L2CAP_FC_A2MP) &&
3122 (conn->feat_mask & L2CAP_FEAT_EXT_WINDOW));
3123 }
3124
3125 static inline bool __l2cap_efs_supported(struct l2cap_conn *conn)
3126 {
3127 return ((conn->local_fixed_chan & L2CAP_FC_A2MP) &&
3128 (conn->feat_mask & L2CAP_FEAT_EXT_FLOW));
3129 }
3130
3131 static void __l2cap_set_ertm_timeouts(struct l2cap_chan *chan,
3132 struct l2cap_conf_rfc *rfc)
3133 {
3134 if (chan->local_amp_id != AMP_ID_BREDR && chan->hs_hcon) {
3135 u64 ertm_to = chan->hs_hcon->hdev->amp_be_flush_to;
3136
3137 /* Class 1 devices have must have ERTM timeouts
3138 * exceeding the Link Supervision Timeout. The
3139 * default Link Supervision Timeout for AMP
3140 * controllers is 10 seconds.
3141 *
3142 * Class 1 devices use 0xffffffff for their
3143 * best-effort flush timeout, so the clamping logic
3144 * will result in a timeout that meets the above
3145 * requirement. ERTM timeouts are 16-bit values, so
3146 * the maximum timeout is 65.535 seconds.
3147 */
3148
3149 /* Convert timeout to milliseconds and round */
3150 ertm_to = DIV_ROUND_UP_ULL(ertm_to, 1000);
3151
3152 /* This is the recommended formula for class 2 devices
3153 * that start ERTM timers when packets are sent to the
3154 * controller.
3155 */
3156 ertm_to = 3 * ertm_to + 500;
3157
3158 if (ertm_to > 0xffff)
3159 ertm_to = 0xffff;
3160
3161 rfc->retrans_timeout = cpu_to_le16((u16) ertm_to);
3162 rfc->monitor_timeout = rfc->retrans_timeout;
3163 } else {
3164 rfc->retrans_timeout = cpu_to_le16(L2CAP_DEFAULT_RETRANS_TO);
3165 rfc->monitor_timeout = cpu_to_le16(L2CAP_DEFAULT_MONITOR_TO);
3166 }
3167 }
3168
3169 static inline void l2cap_txwin_setup(struct l2cap_chan *chan)
3170 {
3171 if (chan->tx_win > L2CAP_DEFAULT_TX_WINDOW &&
3172 __l2cap_ews_supported(chan->conn)) {
3173 /* use extended control field */
3174 set_bit(FLAG_EXT_CTRL, &chan->flags);
3175 chan->tx_win_max = L2CAP_DEFAULT_EXT_WINDOW;
3176 } else {
3177 chan->tx_win = min_t(u16, chan->tx_win,
3178 L2CAP_DEFAULT_TX_WINDOW);
3179 chan->tx_win_max = L2CAP_DEFAULT_TX_WINDOW;
3180 }
3181 chan->ack_win = chan->tx_win;
3182 }
3183
3184 static int l2cap_build_conf_req(struct l2cap_chan *chan, void *data)
3185 {
3186 struct l2cap_conf_req *req = data;
3187 struct l2cap_conf_rfc rfc = { .mode = chan->mode };
3188 void *ptr = req->data;
3189 u16 size;
3190
3191 BT_DBG("chan %p", chan);
3192
3193 if (chan->num_conf_req || chan->num_conf_rsp)
3194 goto done;
3195
3196 switch (chan->mode) {
3197 case L2CAP_MODE_STREAMING:
3198 case L2CAP_MODE_ERTM:
3199 if (test_bit(CONF_STATE2_DEVICE, &chan->conf_state))
3200 break;
3201
3202 if (__l2cap_efs_supported(chan->conn))
3203 set_bit(FLAG_EFS_ENABLE, &chan->flags);
3204
3205 /* fall through */
3206 default:
3207 chan->mode = l2cap_select_mode(rfc.mode, chan->conn->feat_mask);
3208 break;
3209 }
3210
3211 done:
3212 if (chan->imtu != L2CAP_DEFAULT_MTU)
3213 l2cap_add_conf_opt(&ptr, L2CAP_CONF_MTU, 2, chan->imtu);
3214
3215 switch (chan->mode) {
3216 case L2CAP_MODE_BASIC:
3217 if (disable_ertm)
3218 break;
3219
3220 if (!(chan->conn->feat_mask & L2CAP_FEAT_ERTM) &&
3221 !(chan->conn->feat_mask & L2CAP_FEAT_STREAMING))
3222 break;
3223
3224 rfc.mode = L2CAP_MODE_BASIC;
3225 rfc.txwin_size = 0;
3226 rfc.max_transmit = 0;
3227 rfc.retrans_timeout = 0;
3228 rfc.monitor_timeout = 0;
3229 rfc.max_pdu_size = 0;
3230
3231 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3232 (unsigned long) &rfc);
3233 break;
3234
3235 case L2CAP_MODE_ERTM:
3236 rfc.mode = L2CAP_MODE_ERTM;
3237 rfc.max_transmit = chan->max_tx;
3238
3239 __l2cap_set_ertm_timeouts(chan, &rfc);
3240
3241 size = min_t(u16, L2CAP_DEFAULT_MAX_PDU_SIZE, chan->conn->mtu -
3242 L2CAP_EXT_HDR_SIZE - L2CAP_SDULEN_SIZE -
3243 L2CAP_FCS_SIZE);
3244 rfc.max_pdu_size = cpu_to_le16(size);
3245
3246 l2cap_txwin_setup(chan);
3247
3248 rfc.txwin_size = min_t(u16, chan->tx_win,
3249 L2CAP_DEFAULT_TX_WINDOW);
3250
3251 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3252 (unsigned long) &rfc);
3253
3254 if (test_bit(FLAG_EFS_ENABLE, &chan->flags))
3255 l2cap_add_opt_efs(&ptr, chan);
3256
3257 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
3258 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EWS, 2,
3259 chan->tx_win);
3260
3261 if (chan->conn->feat_mask & L2CAP_FEAT_FCS)
3262 if (chan->fcs == L2CAP_FCS_NONE ||
3263 test_bit(CONF_RECV_NO_FCS, &chan->conf_state)) {
3264 chan->fcs = L2CAP_FCS_NONE;
3265 l2cap_add_conf_opt(&ptr, L2CAP_CONF_FCS, 1,
3266 chan->fcs);
3267 }
3268 break;
3269
3270 case L2CAP_MODE_STREAMING:
3271 l2cap_txwin_setup(chan);
3272 rfc.mode = L2CAP_MODE_STREAMING;
3273 rfc.txwin_size = 0;
3274 rfc.max_transmit = 0;
3275 rfc.retrans_timeout = 0;
3276 rfc.monitor_timeout = 0;
3277
3278 size = min_t(u16, L2CAP_DEFAULT_MAX_PDU_SIZE, chan->conn->mtu -
3279 L2CAP_EXT_HDR_SIZE - L2CAP_SDULEN_SIZE -
3280 L2CAP_FCS_SIZE);
3281 rfc.max_pdu_size = cpu_to_le16(size);
3282
3283 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3284 (unsigned long) &rfc);
3285
3286 if (test_bit(FLAG_EFS_ENABLE, &chan->flags))
3287 l2cap_add_opt_efs(&ptr, chan);
3288
3289 if (chan->conn->feat_mask & L2CAP_FEAT_FCS)
3290 if (chan->fcs == L2CAP_FCS_NONE ||
3291 test_bit(CONF_RECV_NO_FCS, &chan->conf_state)) {
3292 chan->fcs = L2CAP_FCS_NONE;
3293 l2cap_add_conf_opt(&ptr, L2CAP_CONF_FCS, 1,
3294 chan->fcs);
3295 }
3296 break;
3297 }
3298
3299 req->dcid = cpu_to_le16(chan->dcid);
3300 req->flags = cpu_to_le16(0);
3301
3302 return ptr - data;
3303 }
3304
3305 static int l2cap_parse_conf_req(struct l2cap_chan *chan, void *data)
3306 {
3307 struct l2cap_conf_rsp *rsp = data;
3308 void *ptr = rsp->data;
3309 void *req = chan->conf_req;
3310 int len = chan->conf_len;
3311 int type, hint, olen;
3312 unsigned long val;
3313 struct l2cap_conf_rfc rfc = { .mode = L2CAP_MODE_BASIC };
3314 struct l2cap_conf_efs efs;
3315 u8 remote_efs = 0;
3316 u16 mtu = L2CAP_DEFAULT_MTU;
3317 u16 result = L2CAP_CONF_SUCCESS;
3318 u16 size;
3319
3320 BT_DBG("chan %p", chan);
3321
3322 while (len >= L2CAP_CONF_OPT_SIZE) {
3323 len -= l2cap_get_conf_opt(&req, &type, &olen, &val);
3324
3325 hint = type & L2CAP_CONF_HINT;
3326 type &= L2CAP_CONF_MASK;
3327
3328 switch (type) {
3329 case L2CAP_CONF_MTU:
3330 mtu = val;
3331 break;
3332
3333 case L2CAP_CONF_FLUSH_TO:
3334 chan->flush_to = val;
3335 break;
3336
3337 case L2CAP_CONF_QOS:
3338 break;
3339
3340 case L2CAP_CONF_RFC:
3341 if (olen == sizeof(rfc))
3342 memcpy(&rfc, (void *) val, olen);
3343 break;
3344
3345 case L2CAP_CONF_FCS:
3346 if (val == L2CAP_FCS_NONE)
3347 set_bit(CONF_RECV_NO_FCS, &chan->conf_state);
3348 break;
3349
3350 case L2CAP_CONF_EFS:
3351 remote_efs = 1;
3352 if (olen == sizeof(efs))
3353 memcpy(&efs, (void *) val, olen);
3354 break;
3355
3356 case L2CAP_CONF_EWS:
3357 if (!(chan->conn->local_fixed_chan & L2CAP_FC_A2MP))
3358 return -ECONNREFUSED;
3359
3360 set_bit(FLAG_EXT_CTRL, &chan->flags);
3361 set_bit(CONF_EWS_RECV, &chan->conf_state);
3362 chan->tx_win_max = L2CAP_DEFAULT_EXT_WINDOW;
3363 chan->remote_tx_win = val;
3364 break;
3365
3366 default:
3367 if (hint)
3368 break;
3369
3370 result = L2CAP_CONF_UNKNOWN;
3371 *((u8 *) ptr++) = type;
3372 break;
3373 }
3374 }
3375
3376 if (chan->num_conf_rsp || chan->num_conf_req > 1)
3377 goto done;
3378
3379 switch (chan->mode) {
3380 case L2CAP_MODE_STREAMING:
3381 case L2CAP_MODE_ERTM:
3382 if (!test_bit(CONF_STATE2_DEVICE, &chan->conf_state)) {
3383 chan->mode = l2cap_select_mode(rfc.mode,
3384 chan->conn->feat_mask);
3385 break;
3386 }
3387
3388 if (remote_efs) {
3389 if (__l2cap_efs_supported(chan->conn))
3390 set_bit(FLAG_EFS_ENABLE, &chan->flags);
3391 else
3392 return -ECONNREFUSED;
3393 }
3394
3395 if (chan->mode != rfc.mode)
3396 return -ECONNREFUSED;
3397
3398 break;
3399 }
3400
3401 done:
3402 if (chan->mode != rfc.mode) {
3403 result = L2CAP_CONF_UNACCEPT;
3404 rfc.mode = chan->mode;
3405
3406 if (chan->num_conf_rsp == 1)
3407 return -ECONNREFUSED;
3408
3409 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3410 (unsigned long) &rfc);
3411 }
3412
3413 if (result == L2CAP_CONF_SUCCESS) {
3414 /* Configure output options and let the other side know
3415 * which ones we don't like. */
3416
3417 if (mtu < L2CAP_DEFAULT_MIN_MTU)
3418 result = L2CAP_CONF_UNACCEPT;
3419 else {
3420 chan->omtu = mtu;
3421 set_bit(CONF_MTU_DONE, &chan->conf_state);
3422 }
3423 l2cap_add_conf_opt(&ptr, L2CAP_CONF_MTU, 2, chan->omtu);
3424
3425 if (remote_efs) {
3426 if (chan->local_stype != L2CAP_SERV_NOTRAFIC &&
3427 efs.stype != L2CAP_SERV_NOTRAFIC &&
3428 efs.stype != chan->local_stype) {
3429
3430 result = L2CAP_CONF_UNACCEPT;
3431
3432 if (chan->num_conf_req >= 1)
3433 return -ECONNREFUSED;
3434
3435 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EFS,
3436 sizeof(efs),
3437 (unsigned long) &efs);
3438 } else {
3439 /* Send PENDING Conf Rsp */
3440 result = L2CAP_CONF_PENDING;
3441 set_bit(CONF_LOC_CONF_PEND, &chan->conf_state);
3442 }
3443 }
3444
3445 switch (rfc.mode) {
3446 case L2CAP_MODE_BASIC:
3447 chan->fcs = L2CAP_FCS_NONE;
3448 set_bit(CONF_MODE_DONE, &chan->conf_state);
3449 break;
3450
3451 case L2CAP_MODE_ERTM:
3452 if (!test_bit(CONF_EWS_RECV, &chan->conf_state))
3453 chan->remote_tx_win = rfc.txwin_size;
3454 else
3455 rfc.txwin_size = L2CAP_DEFAULT_TX_WINDOW;
3456
3457 chan->remote_max_tx = rfc.max_transmit;
3458
3459 size = min_t(u16, le16_to_cpu(rfc.max_pdu_size),
3460 chan->conn->mtu - L2CAP_EXT_HDR_SIZE -
3461 L2CAP_SDULEN_SIZE - L2CAP_FCS_SIZE);
3462 rfc.max_pdu_size = cpu_to_le16(size);
3463 chan->remote_mps = size;
3464
3465 __l2cap_set_ertm_timeouts(chan, &rfc);
3466
3467 set_bit(CONF_MODE_DONE, &chan->conf_state);
3468
3469 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC,
3470 sizeof(rfc), (unsigned long) &rfc);
3471
3472 if (test_bit(FLAG_EFS_ENABLE, &chan->flags)) {
3473 chan->remote_id = efs.id;
3474 chan->remote_stype = efs.stype;
3475 chan->remote_msdu = le16_to_cpu(efs.msdu);
3476 chan->remote_flush_to =
3477 le32_to_cpu(efs.flush_to);
3478 chan->remote_acc_lat =
3479 le32_to_cpu(efs.acc_lat);
3480 chan->remote_sdu_itime =
3481 le32_to_cpu(efs.sdu_itime);
3482 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EFS,
3483 sizeof(efs),
3484 (unsigned long) &efs);
3485 }
3486 break;
3487
3488 case L2CAP_MODE_STREAMING:
3489 size = min_t(u16, le16_to_cpu(rfc.max_pdu_size),
3490 chan->conn->mtu - L2CAP_EXT_HDR_SIZE -
3491 L2CAP_SDULEN_SIZE - L2CAP_FCS_SIZE);
3492 rfc.max_pdu_size = cpu_to_le16(size);
3493 chan->remote_mps = size;
3494
3495 set_bit(CONF_MODE_DONE, &chan->conf_state);
3496
3497 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3498 (unsigned long) &rfc);
3499
3500 break;
3501
3502 default:
3503 result = L2CAP_CONF_UNACCEPT;
3504
3505 memset(&rfc, 0, sizeof(rfc));
3506 rfc.mode = chan->mode;
3507 }
3508
3509 if (result == L2CAP_CONF_SUCCESS)
3510 set_bit(CONF_OUTPUT_DONE, &chan->conf_state);
3511 }
3512 rsp->scid = cpu_to_le16(chan->dcid);
3513 rsp->result = cpu_to_le16(result);
3514 rsp->flags = cpu_to_le16(0);
3515
3516 return ptr - data;
3517 }
3518
3519 static int l2cap_parse_conf_rsp(struct l2cap_chan *chan, void *rsp, int len,
3520 void *data, u16 *result)
3521 {
3522 struct l2cap_conf_req *req = data;
3523 void *ptr = req->data;
3524 int type, olen;
3525 unsigned long val;
3526 struct l2cap_conf_rfc rfc = { .mode = L2CAP_MODE_BASIC };
3527 struct l2cap_conf_efs efs;
3528
3529 BT_DBG("chan %p, rsp %p, len %d, req %p", chan, rsp, len, data);
3530
3531 while (len >= L2CAP_CONF_OPT_SIZE) {
3532 len -= l2cap_get_conf_opt(&rsp, &type, &olen, &val);
3533
3534 switch (type) {
3535 case L2CAP_CONF_MTU:
3536 if (val < L2CAP_DEFAULT_MIN_MTU) {
3537 *result = L2CAP_CONF_UNACCEPT;
3538 chan->imtu = L2CAP_DEFAULT_MIN_MTU;
3539 } else
3540 chan->imtu = val;
3541 l2cap_add_conf_opt(&ptr, L2CAP_CONF_MTU, 2, chan->imtu);
3542 break;
3543
3544 case L2CAP_CONF_FLUSH_TO:
3545 chan->flush_to = val;
3546 l2cap_add_conf_opt(&ptr, L2CAP_CONF_FLUSH_TO,
3547 2, chan->flush_to);
3548 break;
3549
3550 case L2CAP_CONF_RFC:
3551 if (olen == sizeof(rfc))
3552 memcpy(&rfc, (void *)val, olen);
3553
3554 if (test_bit(CONF_STATE2_DEVICE, &chan->conf_state) &&
3555 rfc.mode != chan->mode)
3556 return -ECONNREFUSED;
3557
3558 chan->fcs = 0;
3559
3560 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC,
3561 sizeof(rfc), (unsigned long) &rfc);
3562 break;
3563
3564 case L2CAP_CONF_EWS:
3565 chan->ack_win = min_t(u16, val, chan->ack_win);
3566 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EWS, 2,
3567 chan->tx_win);
3568 break;
3569
3570 case L2CAP_CONF_EFS:
3571 if (olen == sizeof(efs))
3572 memcpy(&efs, (void *)val, olen);
3573
3574 if (chan->local_stype != L2CAP_SERV_NOTRAFIC &&
3575 efs.stype != L2CAP_SERV_NOTRAFIC &&
3576 efs.stype != chan->local_stype)
3577 return -ECONNREFUSED;
3578
3579 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EFS, sizeof(efs),
3580 (unsigned long) &efs);
3581 break;
3582
3583 case L2CAP_CONF_FCS:
3584 if (*result == L2CAP_CONF_PENDING)
3585 if (val == L2CAP_FCS_NONE)
3586 set_bit(CONF_RECV_NO_FCS,
3587 &chan->conf_state);
3588 break;
3589 }
3590 }
3591
3592 if (chan->mode == L2CAP_MODE_BASIC && chan->mode != rfc.mode)
3593 return -ECONNREFUSED;
3594
3595 chan->mode = rfc.mode;
3596
3597 if (*result == L2CAP_CONF_SUCCESS || *result == L2CAP_CONF_PENDING) {
3598 switch (rfc.mode) {
3599 case L2CAP_MODE_ERTM:
3600 chan->retrans_timeout = le16_to_cpu(rfc.retrans_timeout);
3601 chan->monitor_timeout = le16_to_cpu(rfc.monitor_timeout);
3602 chan->mps = le16_to_cpu(rfc.max_pdu_size);
3603 if (!test_bit(FLAG_EXT_CTRL, &chan->flags))
3604 chan->ack_win = min_t(u16, chan->ack_win,
3605 rfc.txwin_size);
3606
3607 if (test_bit(FLAG_EFS_ENABLE, &chan->flags)) {
3608 chan->local_msdu = le16_to_cpu(efs.msdu);
3609 chan->local_sdu_itime =
3610 le32_to_cpu(efs.sdu_itime);
3611 chan->local_acc_lat = le32_to_cpu(efs.acc_lat);
3612 chan->local_flush_to =
3613 le32_to_cpu(efs.flush_to);
3614 }
3615 break;
3616
3617 case L2CAP_MODE_STREAMING:
3618 chan->mps = le16_to_cpu(rfc.max_pdu_size);
3619 }
3620 }
3621
3622 req->dcid = cpu_to_le16(chan->dcid);
3623 req->flags = cpu_to_le16(0);
3624
3625 return ptr - data;
3626 }
3627
3628 static int l2cap_build_conf_rsp(struct l2cap_chan *chan, void *data,
3629 u16 result, u16 flags)
3630 {
3631 struct l2cap_conf_rsp *rsp = data;
3632 void *ptr = rsp->data;
3633
3634 BT_DBG("chan %p", chan);
3635
3636 rsp->scid = cpu_to_le16(chan->dcid);
3637 rsp->result = cpu_to_le16(result);
3638 rsp->flags = cpu_to_le16(flags);
3639
3640 return ptr - data;
3641 }
3642
3643 void __l2cap_le_connect_rsp_defer(struct l2cap_chan *chan)
3644 {
3645 struct l2cap_le_conn_rsp rsp;
3646 struct l2cap_conn *conn = chan->conn;
3647
3648 BT_DBG("chan %p", chan);
3649
3650 rsp.dcid = cpu_to_le16(chan->scid);
3651 rsp.mtu = cpu_to_le16(chan->imtu);
3652 rsp.mps = cpu_to_le16(chan->mps);
3653 rsp.credits = cpu_to_le16(chan->rx_credits);
3654 rsp.result = cpu_to_le16(L2CAP_CR_SUCCESS);
3655
3656 l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CONN_RSP, sizeof(rsp),
3657 &rsp);
3658 }
3659
3660 void __l2cap_connect_rsp_defer(struct l2cap_chan *chan)
3661 {
3662 struct l2cap_conn_rsp rsp;
3663 struct l2cap_conn *conn = chan->conn;
3664 u8 buf[128];
3665 u8 rsp_code;
3666
3667 rsp.scid = cpu_to_le16(chan->dcid);
3668 rsp.dcid = cpu_to_le16(chan->scid);
3669 rsp.result = cpu_to_le16(L2CAP_CR_SUCCESS);
3670 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
3671
3672 if (chan->hs_hcon)
3673 rsp_code = L2CAP_CREATE_CHAN_RSP;
3674 else
3675 rsp_code = L2CAP_CONN_RSP;
3676
3677 BT_DBG("chan %p rsp_code %u", chan, rsp_code);
3678
3679 l2cap_send_cmd(conn, chan->ident, rsp_code, sizeof(rsp), &rsp);
3680
3681 if (test_and_set_bit(CONF_REQ_SENT, &chan->conf_state))
3682 return;
3683
3684 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
3685 l2cap_build_conf_req(chan, buf), buf);
3686 chan->num_conf_req++;
3687 }
3688
3689 static void l2cap_conf_rfc_get(struct l2cap_chan *chan, void *rsp, int len)
3690 {
3691 int type, olen;
3692 unsigned long val;
3693 /* Use sane default values in case a misbehaving remote device
3694 * did not send an RFC or extended window size option.
3695 */
3696 u16 txwin_ext = chan->ack_win;
3697 struct l2cap_conf_rfc rfc = {
3698 .mode = chan->mode,
3699 .retrans_timeout = cpu_to_le16(L2CAP_DEFAULT_RETRANS_TO),
3700 .monitor_timeout = cpu_to_le16(L2CAP_DEFAULT_MONITOR_TO),
3701 .max_pdu_size = cpu_to_le16(chan->imtu),
3702 .txwin_size = min_t(u16, chan->ack_win, L2CAP_DEFAULT_TX_WINDOW),
3703 };
3704
3705 BT_DBG("chan %p, rsp %p, len %d", chan, rsp, len);
3706
3707 if ((chan->mode != L2CAP_MODE_ERTM) && (chan->mode != L2CAP_MODE_STREAMING))
3708 return;
3709
3710 while (len >= L2CAP_CONF_OPT_SIZE) {
3711 len -= l2cap_get_conf_opt(&rsp, &type, &olen, &val);
3712
3713 switch (type) {
3714 case L2CAP_CONF_RFC:
3715 if (olen == sizeof(rfc))
3716 memcpy(&rfc, (void *)val, olen);
3717 break;
3718 case L2CAP_CONF_EWS:
3719 txwin_ext = val;
3720 break;
3721 }
3722 }
3723
3724 switch (rfc.mode) {
3725 case L2CAP_MODE_ERTM:
3726 chan->retrans_timeout = le16_to_cpu(rfc.retrans_timeout);
3727 chan->monitor_timeout = le16_to_cpu(rfc.monitor_timeout);
3728 chan->mps = le16_to_cpu(rfc.max_pdu_size);
3729 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
3730 chan->ack_win = min_t(u16, chan->ack_win, txwin_ext);
3731 else
3732 chan->ack_win = min_t(u16, chan->ack_win,
3733 rfc.txwin_size);
3734 break;
3735 case L2CAP_MODE_STREAMING:
3736 chan->mps = le16_to_cpu(rfc.max_pdu_size);
3737 }
3738 }
3739
3740 static inline int l2cap_command_rej(struct l2cap_conn *conn,
3741 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
3742 u8 *data)
3743 {
3744 struct l2cap_cmd_rej_unk *rej = (struct l2cap_cmd_rej_unk *) data;
3745
3746 if (cmd_len < sizeof(*rej))
3747 return -EPROTO;
3748
3749 if (rej->reason != L2CAP_REJ_NOT_UNDERSTOOD)
3750 return 0;
3751
3752 if ((conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT) &&
3753 cmd->ident == conn->info_ident) {
3754 cancel_delayed_work(&conn->info_timer);
3755
3756 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
3757 conn->info_ident = 0;
3758
3759 l2cap_conn_start(conn);
3760 }
3761
3762 return 0;
3763 }
3764
3765 static struct l2cap_chan *l2cap_connect(struct l2cap_conn *conn,
3766 struct l2cap_cmd_hdr *cmd,
3767 u8 *data, u8 rsp_code, u8 amp_id)
3768 {
3769 struct l2cap_conn_req *req = (struct l2cap_conn_req *) data;
3770 struct l2cap_conn_rsp rsp;
3771 struct l2cap_chan *chan = NULL, *pchan;
3772 int result, status = L2CAP_CS_NO_INFO;
3773
3774 u16 dcid = 0, scid = __le16_to_cpu(req->scid);
3775 __le16 psm = req->psm;
3776
3777 BT_DBG("psm 0x%2.2x scid 0x%4.4x", __le16_to_cpu(psm), scid);
3778
3779 /* Check if we have socket listening on psm */
3780 pchan = l2cap_global_chan_by_psm(BT_LISTEN, psm, &conn->hcon->src,
3781 &conn->hcon->dst, ACL_LINK);
3782 if (!pchan) {
3783 result = L2CAP_CR_BAD_PSM;
3784 goto sendresp;
3785 }
3786
3787 mutex_lock(&conn->chan_lock);
3788 l2cap_chan_lock(pchan);
3789
3790 /* Check if the ACL is secure enough (if not SDP) */
3791 if (psm != cpu_to_le16(L2CAP_PSM_SDP) &&
3792 !hci_conn_check_link_mode(conn->hcon)) {
3793 conn->disc_reason = HCI_ERROR_AUTH_FAILURE;
3794 result = L2CAP_CR_SEC_BLOCK;
3795 goto response;
3796 }
3797
3798 result = L2CAP_CR_NO_MEM;
3799
3800 /* Check if we already have channel with that dcid */
3801 if (__l2cap_get_chan_by_dcid(conn, scid))
3802 goto response;
3803
3804 chan = pchan->ops->new_connection(pchan);
3805 if (!chan)
3806 goto response;
3807
3808 /* For certain devices (ex: HID mouse), support for authentication,
3809 * pairing and bonding is optional. For such devices, inorder to avoid
3810 * the ACL alive for too long after L2CAP disconnection, reset the ACL
3811 * disc_timeout back to HCI_DISCONN_TIMEOUT during L2CAP connect.
3812 */
3813 conn->hcon->disc_timeout = HCI_DISCONN_TIMEOUT;
3814
3815 bacpy(&chan->src, &conn->hcon->src);
3816 bacpy(&chan->dst, &conn->hcon->dst);
3817 chan->src_type = bdaddr_src_type(conn->hcon);
3818 chan->dst_type = bdaddr_dst_type(conn->hcon);
3819 chan->psm = psm;
3820 chan->dcid = scid;
3821 chan->local_amp_id = amp_id;
3822
3823 __l2cap_chan_add(conn, chan);
3824
3825 dcid = chan->scid;
3826
3827 __set_chan_timer(chan, chan->ops->get_sndtimeo(chan));
3828
3829 chan->ident = cmd->ident;
3830
3831 if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE) {
3832 if (l2cap_chan_check_security(chan, false)) {
3833 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) {
3834 l2cap_state_change(chan, BT_CONNECT2);
3835 result = L2CAP_CR_PEND;
3836 status = L2CAP_CS_AUTHOR_PEND;
3837 chan->ops->defer(chan);
3838 } else {
3839 /* Force pending result for AMP controllers.
3840 * The connection will succeed after the
3841 * physical link is up.
3842 */
3843 if (amp_id == AMP_ID_BREDR) {
3844 l2cap_state_change(chan, BT_CONFIG);
3845 result = L2CAP_CR_SUCCESS;
3846 } else {
3847 l2cap_state_change(chan, BT_CONNECT2);
3848 result = L2CAP_CR_PEND;
3849 }
3850 status = L2CAP_CS_NO_INFO;
3851 }
3852 } else {
3853 l2cap_state_change(chan, BT_CONNECT2);
3854 result = L2CAP_CR_PEND;
3855 status = L2CAP_CS_AUTHEN_PEND;
3856 }
3857 } else {
3858 l2cap_state_change(chan, BT_CONNECT2);
3859 result = L2CAP_CR_PEND;
3860 status = L2CAP_CS_NO_INFO;
3861 }
3862
3863 response:
3864 l2cap_chan_unlock(pchan);
3865 mutex_unlock(&conn->chan_lock);
3866 l2cap_chan_put(pchan);
3867
3868 sendresp:
3869 rsp.scid = cpu_to_le16(scid);
3870 rsp.dcid = cpu_to_le16(dcid);
3871 rsp.result = cpu_to_le16(result);
3872 rsp.status = cpu_to_le16(status);
3873 l2cap_send_cmd(conn, cmd->ident, rsp_code, sizeof(rsp), &rsp);
3874
3875 if (result == L2CAP_CR_PEND && status == L2CAP_CS_NO_INFO) {
3876 struct l2cap_info_req info;
3877 info.type = cpu_to_le16(L2CAP_IT_FEAT_MASK);
3878
3879 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_SENT;
3880 conn->info_ident = l2cap_get_ident(conn);
3881
3882 schedule_delayed_work(&conn->info_timer, L2CAP_INFO_TIMEOUT);
3883
3884 l2cap_send_cmd(conn, conn->info_ident, L2CAP_INFO_REQ,
3885 sizeof(info), &info);
3886 }
3887
3888 if (chan && !test_bit(CONF_REQ_SENT, &chan->conf_state) &&
3889 result == L2CAP_CR_SUCCESS) {
3890 u8 buf[128];
3891 set_bit(CONF_REQ_SENT, &chan->conf_state);
3892 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
3893 l2cap_build_conf_req(chan, buf), buf);
3894 chan->num_conf_req++;
3895 }
3896
3897 return chan;
3898 }
3899
3900 static int l2cap_connect_req(struct l2cap_conn *conn,
3901 struct l2cap_cmd_hdr *cmd, u16 cmd_len, u8 *data)
3902 {
3903 struct hci_dev *hdev = conn->hcon->hdev;
3904 struct hci_conn *hcon = conn->hcon;
3905
3906 if (cmd_len < sizeof(struct l2cap_conn_req))
3907 return -EPROTO;
3908
3909 hci_dev_lock(hdev);
3910 if (hci_dev_test_flag(hdev, HCI_MGMT) &&
3911 !test_and_set_bit(HCI_CONN_MGMT_CONNECTED, &hcon->flags))
3912 mgmt_device_connected(hdev, hcon, 0, NULL, 0);
3913 hci_dev_unlock(hdev);
3914
3915 l2cap_connect(conn, cmd, data, L2CAP_CONN_RSP, 0);
3916 return 0;
3917 }
3918
3919 static int l2cap_connect_create_rsp(struct l2cap_conn *conn,
3920 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
3921 u8 *data)
3922 {
3923 struct l2cap_conn_rsp *rsp = (struct l2cap_conn_rsp *) data;
3924 u16 scid, dcid, result, status;
3925 struct l2cap_chan *chan;
3926 u8 req[128];
3927 int err;
3928
3929 if (cmd_len < sizeof(*rsp))
3930 return -EPROTO;
3931
3932 scid = __le16_to_cpu(rsp->scid);
3933 dcid = __le16_to_cpu(rsp->dcid);
3934 result = __le16_to_cpu(rsp->result);
3935 status = __le16_to_cpu(rsp->status);
3936
3937 BT_DBG("dcid 0x%4.4x scid 0x%4.4x result 0x%2.2x status 0x%2.2x",
3938 dcid, scid, result, status);
3939
3940 mutex_lock(&conn->chan_lock);
3941
3942 if (scid) {
3943 chan = __l2cap_get_chan_by_scid(conn, scid);
3944 if (!chan) {
3945 err = -EBADSLT;
3946 goto unlock;
3947 }
3948 } else {
3949 chan = __l2cap_get_chan_by_ident(conn, cmd->ident);
3950 if (!chan) {
3951 err = -EBADSLT;
3952 goto unlock;
3953 }
3954 }
3955
3956 err = 0;
3957
3958 l2cap_chan_lock(chan);
3959
3960 switch (result) {
3961 case L2CAP_CR_SUCCESS:
3962 l2cap_state_change(chan, BT_CONFIG);
3963 chan->ident = 0;
3964 chan->dcid = dcid;
3965 clear_bit(CONF_CONNECT_PEND, &chan->conf_state);
3966
3967 if (test_and_set_bit(CONF_REQ_SENT, &chan->conf_state))
3968 break;
3969
3970 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
3971 l2cap_build_conf_req(chan, req), req);
3972 chan->num_conf_req++;
3973 break;
3974
3975 case L2CAP_CR_PEND:
3976 set_bit(CONF_CONNECT_PEND, &chan->conf_state);
3977 break;
3978
3979 default:
3980 l2cap_chan_del(chan, ECONNREFUSED);
3981 break;
3982 }
3983
3984 l2cap_chan_unlock(chan);
3985
3986 unlock:
3987 mutex_unlock(&conn->chan_lock);
3988
3989 return err;
3990 }
3991
3992 static inline void set_default_fcs(struct l2cap_chan *chan)
3993 {
3994 /* FCS is enabled only in ERTM or streaming mode, if one or both
3995 * sides request it.
3996 */
3997 if (chan->mode != L2CAP_MODE_ERTM && chan->mode != L2CAP_MODE_STREAMING)
3998 chan->fcs = L2CAP_FCS_NONE;
3999 else if (!test_bit(CONF_RECV_NO_FCS, &chan->conf_state))
4000 chan->fcs = L2CAP_FCS_CRC16;
4001 }
4002
4003 static void l2cap_send_efs_conf_rsp(struct l2cap_chan *chan, void *data,
4004 u8 ident, u16 flags)
4005 {
4006 struct l2cap_conn *conn = chan->conn;
4007
4008 BT_DBG("conn %p chan %p ident %d flags 0x%4.4x", conn, chan, ident,
4009 flags);
4010
4011 clear_bit(CONF_LOC_CONF_PEND, &chan->conf_state);
4012 set_bit(CONF_OUTPUT_DONE, &chan->conf_state);
4013
4014 l2cap_send_cmd(conn, ident, L2CAP_CONF_RSP,
4015 l2cap_build_conf_rsp(chan, data,
4016 L2CAP_CONF_SUCCESS, flags), data);
4017 }
4018
4019 static void cmd_reject_invalid_cid(struct l2cap_conn *conn, u8 ident,
4020 u16 scid, u16 dcid)
4021 {
4022 struct l2cap_cmd_rej_cid rej;
4023
4024 rej.reason = cpu_to_le16(L2CAP_REJ_INVALID_CID);
4025 rej.scid = __cpu_to_le16(scid);
4026 rej.dcid = __cpu_to_le16(dcid);
4027
4028 l2cap_send_cmd(conn, ident, L2CAP_COMMAND_REJ, sizeof(rej), &rej);
4029 }
4030
4031 static inline int l2cap_config_req(struct l2cap_conn *conn,
4032 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4033 u8 *data)
4034 {
4035 struct l2cap_conf_req *req = (struct l2cap_conf_req *) data;
4036 u16 dcid, flags;
4037 u8 rsp[64];
4038 struct l2cap_chan *chan;
4039 int len, err = 0;
4040
4041 if (cmd_len < sizeof(*req))
4042 return -EPROTO;
4043
4044 dcid = __le16_to_cpu(req->dcid);
4045 flags = __le16_to_cpu(req->flags);
4046
4047 BT_DBG("dcid 0x%4.4x flags 0x%2.2x", dcid, flags);
4048
4049 chan = l2cap_get_chan_by_scid(conn, dcid);
4050 if (!chan) {
4051 cmd_reject_invalid_cid(conn, cmd->ident, dcid, 0);
4052 return 0;
4053 }
4054
4055 if (chan->state != BT_CONFIG && chan->state != BT_CONNECT2) {
4056 cmd_reject_invalid_cid(conn, cmd->ident, chan->scid,
4057 chan->dcid);
4058 goto unlock;
4059 }
4060
4061 /* Reject if config buffer is too small. */
4062 len = cmd_len - sizeof(*req);
4063 if (chan->conf_len + len > sizeof(chan->conf_req)) {
4064 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP,
4065 l2cap_build_conf_rsp(chan, rsp,
4066 L2CAP_CONF_REJECT, flags), rsp);
4067 goto unlock;
4068 }
4069
4070 /* Store config. */
4071 memcpy(chan->conf_req + chan->conf_len, req->data, len);
4072 chan->conf_len += len;
4073
4074 if (flags & L2CAP_CONF_FLAG_CONTINUATION) {
4075 /* Incomplete config. Send empty response. */
4076 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP,
4077 l2cap_build_conf_rsp(chan, rsp,
4078 L2CAP_CONF_SUCCESS, flags), rsp);
4079 goto unlock;
4080 }
4081
4082 /* Complete config. */
4083 len = l2cap_parse_conf_req(chan, rsp);
4084 if (len < 0) {
4085 l2cap_send_disconn_req(chan, ECONNRESET);
4086 goto unlock;
4087 }
4088
4089 chan->ident = cmd->ident;
4090 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP, len, rsp);
4091 chan->num_conf_rsp++;
4092
4093 /* Reset config buffer. */
4094 chan->conf_len = 0;
4095
4096 if (!test_bit(CONF_OUTPUT_DONE, &chan->conf_state))
4097 goto unlock;
4098
4099 if (test_bit(CONF_INPUT_DONE, &chan->conf_state)) {
4100 set_default_fcs(chan);
4101
4102 if (chan->mode == L2CAP_MODE_ERTM ||
4103 chan->mode == L2CAP_MODE_STREAMING)
4104 err = l2cap_ertm_init(chan);
4105
4106 if (err < 0)
4107 l2cap_send_disconn_req(chan, -err);
4108 else
4109 l2cap_chan_ready(chan);
4110
4111 goto unlock;
4112 }
4113
4114 if (!test_and_set_bit(CONF_REQ_SENT, &chan->conf_state)) {
4115 u8 buf[64];
4116 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
4117 l2cap_build_conf_req(chan, buf), buf);
4118 chan->num_conf_req++;
4119 }
4120
4121 /* Got Conf Rsp PENDING from remote side and assume we sent
4122 Conf Rsp PENDING in the code above */
4123 if (test_bit(CONF_REM_CONF_PEND, &chan->conf_state) &&
4124 test_bit(CONF_LOC_CONF_PEND, &chan->conf_state)) {
4125
4126 /* check compatibility */
4127
4128 /* Send rsp for BR/EDR channel */
4129 if (!chan->hs_hcon)
4130 l2cap_send_efs_conf_rsp(chan, rsp, cmd->ident, flags);
4131 else
4132 chan->ident = cmd->ident;
4133 }
4134
4135 unlock:
4136 l2cap_chan_unlock(chan);
4137 return err;
4138 }
4139
4140 static inline int l2cap_config_rsp(struct l2cap_conn *conn,
4141 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4142 u8 *data)
4143 {
4144 struct l2cap_conf_rsp *rsp = (struct l2cap_conf_rsp *)data;
4145 u16 scid, flags, result;
4146 struct l2cap_chan *chan;
4147 int len = cmd_len - sizeof(*rsp);
4148 int err = 0;
4149
4150 if (cmd_len < sizeof(*rsp))
4151 return -EPROTO;
4152
4153 scid = __le16_to_cpu(rsp->scid);
4154 flags = __le16_to_cpu(rsp->flags);
4155 result = __le16_to_cpu(rsp->result);
4156
4157 BT_DBG("scid 0x%4.4x flags 0x%2.2x result 0x%2.2x len %d", scid, flags,
4158 result, len);
4159
4160 chan = l2cap_get_chan_by_scid(conn, scid);
4161 if (!chan)
4162 return 0;
4163
4164 switch (result) {
4165 case L2CAP_CONF_SUCCESS:
4166 l2cap_conf_rfc_get(chan, rsp->data, len);
4167 clear_bit(CONF_REM_CONF_PEND, &chan->conf_state);
4168 break;
4169
4170 case L2CAP_CONF_PENDING:
4171 set_bit(CONF_REM_CONF_PEND, &chan->conf_state);
4172
4173 if (test_bit(CONF_LOC_CONF_PEND, &chan->conf_state)) {
4174 char buf[64];
4175
4176 len = l2cap_parse_conf_rsp(chan, rsp->data, len,
4177 buf, &result);
4178 if (len < 0) {
4179 l2cap_send_disconn_req(chan, ECONNRESET);
4180 goto done;
4181 }
4182
4183 if (!chan->hs_hcon) {
4184 l2cap_send_efs_conf_rsp(chan, buf, cmd->ident,
4185 0);
4186 } else {
4187 if (l2cap_check_efs(chan)) {
4188 amp_create_logical_link(chan);
4189 chan->ident = cmd->ident;
4190 }
4191 }
4192 }
4193 goto done;
4194
4195 case L2CAP_CONF_UNACCEPT:
4196 if (chan->num_conf_rsp <= L2CAP_CONF_MAX_CONF_RSP) {
4197 char req[64];
4198
4199 if (len > sizeof(req) - sizeof(struct l2cap_conf_req)) {
4200 l2cap_send_disconn_req(chan, ECONNRESET);
4201 goto done;
4202 }
4203
4204 /* throw out any old stored conf requests */
4205 result = L2CAP_CONF_SUCCESS;
4206 len = l2cap_parse_conf_rsp(chan, rsp->data, len,
4207 req, &result);
4208 if (len < 0) {
4209 l2cap_send_disconn_req(chan, ECONNRESET);
4210 goto done;
4211 }
4212
4213 l2cap_send_cmd(conn, l2cap_get_ident(conn),
4214 L2CAP_CONF_REQ, len, req);
4215 chan->num_conf_req++;
4216 if (result != L2CAP_CONF_SUCCESS)
4217 goto done;
4218 break;
4219 }
4220
4221 default:
4222 l2cap_chan_set_err(chan, ECONNRESET);
4223
4224 __set_chan_timer(chan, L2CAP_DISC_REJ_TIMEOUT);
4225 l2cap_send_disconn_req(chan, ECONNRESET);
4226 goto done;
4227 }
4228
4229 if (flags & L2CAP_CONF_FLAG_CONTINUATION)
4230 goto done;
4231
4232 set_bit(CONF_INPUT_DONE, &chan->conf_state);
4233
4234 if (test_bit(CONF_OUTPUT_DONE, &chan->conf_state)) {
4235 set_default_fcs(chan);
4236
4237 if (chan->mode == L2CAP_MODE_ERTM ||
4238 chan->mode == L2CAP_MODE_STREAMING)
4239 err = l2cap_ertm_init(chan);
4240
4241 if (err < 0)
4242 l2cap_send_disconn_req(chan, -err);
4243 else
4244 l2cap_chan_ready(chan);
4245 }
4246
4247 done:
4248 l2cap_chan_unlock(chan);
4249 return err;
4250 }
4251
4252 static inline int l2cap_disconnect_req(struct l2cap_conn *conn,
4253 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4254 u8 *data)
4255 {
4256 struct l2cap_disconn_req *req = (struct l2cap_disconn_req *) data;
4257 struct l2cap_disconn_rsp rsp;
4258 u16 dcid, scid;
4259 struct l2cap_chan *chan;
4260
4261 if (cmd_len != sizeof(*req))
4262 return -EPROTO;
4263
4264 scid = __le16_to_cpu(req->scid);
4265 dcid = __le16_to_cpu(req->dcid);
4266
4267 BT_DBG("scid 0x%4.4x dcid 0x%4.4x", scid, dcid);
4268
4269 mutex_lock(&conn->chan_lock);
4270
4271 chan = __l2cap_get_chan_by_scid(conn, dcid);
4272 if (!chan) {
4273 mutex_unlock(&conn->chan_lock);
4274 cmd_reject_invalid_cid(conn, cmd->ident, dcid, scid);
4275 return 0;
4276 }
4277
4278 l2cap_chan_lock(chan);
4279
4280 rsp.dcid = cpu_to_le16(chan->scid);
4281 rsp.scid = cpu_to_le16(chan->dcid);
4282 l2cap_send_cmd(conn, cmd->ident, L2CAP_DISCONN_RSP, sizeof(rsp), &rsp);
4283
4284 chan->ops->set_shutdown(chan);
4285
4286 l2cap_chan_hold(chan);
4287 l2cap_chan_del(chan, ECONNRESET);
4288
4289 l2cap_chan_unlock(chan);
4290
4291 chan->ops->close(chan);
4292 l2cap_chan_put(chan);
4293
4294 mutex_unlock(&conn->chan_lock);
4295
4296 return 0;
4297 }
4298
4299 static inline int l2cap_disconnect_rsp(struct l2cap_conn *conn,
4300 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4301 u8 *data)
4302 {
4303 struct l2cap_disconn_rsp *rsp = (struct l2cap_disconn_rsp *) data;
4304 u16 dcid, scid;
4305 struct l2cap_chan *chan;
4306
4307 if (cmd_len != sizeof(*rsp))
4308 return -EPROTO;
4309
4310 scid = __le16_to_cpu(rsp->scid);
4311 dcid = __le16_to_cpu(rsp->dcid);
4312
4313 BT_DBG("dcid 0x%4.4x scid 0x%4.4x", dcid, scid);
4314
4315 mutex_lock(&conn->chan_lock);
4316
4317 chan = __l2cap_get_chan_by_scid(conn, scid);
4318 if (!chan) {
4319 mutex_unlock(&conn->chan_lock);
4320 return 0;
4321 }
4322
4323 l2cap_chan_lock(chan);
4324
4325 l2cap_chan_hold(chan);
4326 l2cap_chan_del(chan, 0);
4327
4328 l2cap_chan_unlock(chan);
4329
4330 chan->ops->close(chan);
4331 l2cap_chan_put(chan);
4332
4333 mutex_unlock(&conn->chan_lock);
4334
4335 return 0;
4336 }
4337
4338 static inline int l2cap_information_req(struct l2cap_conn *conn,
4339 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4340 u8 *data)
4341 {
4342 struct l2cap_info_req *req = (struct l2cap_info_req *) data;
4343 u16 type;
4344
4345 if (cmd_len != sizeof(*req))
4346 return -EPROTO;
4347
4348 type = __le16_to_cpu(req->type);
4349
4350 BT_DBG("type 0x%4.4x", type);
4351
4352 if (type == L2CAP_IT_FEAT_MASK) {
4353 u8 buf[8];
4354 u32 feat_mask = l2cap_feat_mask;
4355 struct l2cap_info_rsp *rsp = (struct l2cap_info_rsp *) buf;
4356 rsp->type = cpu_to_le16(L2CAP_IT_FEAT_MASK);
4357 rsp->result = cpu_to_le16(L2CAP_IR_SUCCESS);
4358 if (!disable_ertm)
4359 feat_mask |= L2CAP_FEAT_ERTM | L2CAP_FEAT_STREAMING
4360 | L2CAP_FEAT_FCS;
4361 if (conn->local_fixed_chan & L2CAP_FC_A2MP)
4362 feat_mask |= L2CAP_FEAT_EXT_FLOW
4363 | L2CAP_FEAT_EXT_WINDOW;
4364
4365 put_unaligned_le32(feat_mask, rsp->data);
4366 l2cap_send_cmd(conn, cmd->ident, L2CAP_INFO_RSP, sizeof(buf),
4367 buf);
4368 } else if (type == L2CAP_IT_FIXED_CHAN) {
4369 u8 buf[12];
4370 struct l2cap_info_rsp *rsp = (struct l2cap_info_rsp *) buf;
4371
4372 rsp->type = cpu_to_le16(L2CAP_IT_FIXED_CHAN);
4373 rsp->result = cpu_to_le16(L2CAP_IR_SUCCESS);
4374 rsp->data[0] = conn->local_fixed_chan;
4375 memset(rsp->data + 1, 0, 7);
4376 l2cap_send_cmd(conn, cmd->ident, L2CAP_INFO_RSP, sizeof(buf),
4377 buf);
4378 } else {
4379 struct l2cap_info_rsp rsp;
4380 rsp.type = cpu_to_le16(type);
4381 rsp.result = cpu_to_le16(L2CAP_IR_NOTSUPP);
4382 l2cap_send_cmd(conn, cmd->ident, L2CAP_INFO_RSP, sizeof(rsp),
4383 &rsp);
4384 }
4385
4386 return 0;
4387 }
4388
4389 static inline int l2cap_information_rsp(struct l2cap_conn *conn,
4390 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4391 u8 *data)
4392 {
4393 struct l2cap_info_rsp *rsp = (struct l2cap_info_rsp *) data;
4394 u16 type, result;
4395
4396 if (cmd_len < sizeof(*rsp))
4397 return -EPROTO;
4398
4399 type = __le16_to_cpu(rsp->type);
4400 result = __le16_to_cpu(rsp->result);
4401
4402 BT_DBG("type 0x%4.4x result 0x%2.2x", type, result);
4403
4404 /* L2CAP Info req/rsp are unbound to channels, add extra checks */
4405 if (cmd->ident != conn->info_ident ||
4406 conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE)
4407 return 0;
4408
4409 cancel_delayed_work(&conn->info_timer);
4410
4411 if (result != L2CAP_IR_SUCCESS) {
4412 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
4413 conn->info_ident = 0;
4414
4415 l2cap_conn_start(conn);
4416
4417 return 0;
4418 }
4419
4420 switch (type) {
4421 case L2CAP_IT_FEAT_MASK:
4422 conn->feat_mask = get_unaligned_le32(rsp->data);
4423
4424 if (conn->feat_mask & L2CAP_FEAT_FIXED_CHAN) {
4425 struct l2cap_info_req req;
4426 req.type = cpu_to_le16(L2CAP_IT_FIXED_CHAN);
4427
4428 conn->info_ident = l2cap_get_ident(conn);
4429
4430 l2cap_send_cmd(conn, conn->info_ident,
4431 L2CAP_INFO_REQ, sizeof(req), &req);
4432 } else {
4433 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
4434 conn->info_ident = 0;
4435
4436 l2cap_conn_start(conn);
4437 }
4438 break;
4439
4440 case L2CAP_IT_FIXED_CHAN:
4441 conn->remote_fixed_chan = rsp->data[0];
4442 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
4443 conn->info_ident = 0;
4444
4445 l2cap_conn_start(conn);
4446 break;
4447 }
4448
4449 return 0;
4450 }
4451
4452 static int l2cap_create_channel_req(struct l2cap_conn *conn,
4453 struct l2cap_cmd_hdr *cmd,
4454 u16 cmd_len, void *data)
4455 {
4456 struct l2cap_create_chan_req *req = data;
4457 struct l2cap_create_chan_rsp rsp;
4458 struct l2cap_chan *chan;
4459 struct hci_dev *hdev;
4460 u16 psm, scid;
4461
4462 if (cmd_len != sizeof(*req))
4463 return -EPROTO;
4464
4465 if (!(conn->local_fixed_chan & L2CAP_FC_A2MP))
4466 return -EINVAL;
4467
4468 psm = le16_to_cpu(req->psm);
4469 scid = le16_to_cpu(req->scid);
4470
4471 BT_DBG("psm 0x%2.2x, scid 0x%4.4x, amp_id %d", psm, scid, req->amp_id);
4472
4473 /* For controller id 0 make BR/EDR connection */
4474 if (req->amp_id == AMP_ID_BREDR) {
4475 l2cap_connect(conn, cmd, data, L2CAP_CREATE_CHAN_RSP,
4476 req->amp_id);
4477 return 0;
4478 }
4479
4480 /* Validate AMP controller id */
4481 hdev = hci_dev_get(req->amp_id);
4482 if (!hdev)
4483 goto error;
4484
4485 if (hdev->dev_type != HCI_AMP || !test_bit(HCI_UP, &hdev->flags)) {
4486 hci_dev_put(hdev);
4487 goto error;
4488 }
4489
4490 chan = l2cap_connect(conn, cmd, data, L2CAP_CREATE_CHAN_RSP,
4491 req->amp_id);
4492 if (chan) {
4493 struct amp_mgr *mgr = conn->hcon->amp_mgr;
4494 struct hci_conn *hs_hcon;
4495
4496 hs_hcon = hci_conn_hash_lookup_ba(hdev, AMP_LINK,
4497 &conn->hcon->dst);
4498 if (!hs_hcon) {
4499 hci_dev_put(hdev);
4500 cmd_reject_invalid_cid(conn, cmd->ident, chan->scid,
4501 chan->dcid);
4502 return 0;
4503 }
4504
4505 BT_DBG("mgr %p bredr_chan %p hs_hcon %p", mgr, chan, hs_hcon);
4506
4507 mgr->bredr_chan = chan;
4508 chan->hs_hcon = hs_hcon;
4509 chan->fcs = L2CAP_FCS_NONE;
4510 conn->mtu = hdev->block_mtu;
4511 }
4512
4513 hci_dev_put(hdev);
4514
4515 return 0;
4516
4517 error:
4518 rsp.dcid = 0;
4519 rsp.scid = cpu_to_le16(scid);
4520 rsp.result = cpu_to_le16(L2CAP_CR_BAD_AMP);
4521 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
4522
4523 l2cap_send_cmd(conn, cmd->ident, L2CAP_CREATE_CHAN_RSP,
4524 sizeof(rsp), &rsp);
4525
4526 return 0;
4527 }
4528
4529 static void l2cap_send_move_chan_req(struct l2cap_chan *chan, u8 dest_amp_id)
4530 {
4531 struct l2cap_move_chan_req req;
4532 u8 ident;
4533
4534 BT_DBG("chan %p, dest_amp_id %d", chan, dest_amp_id);
4535
4536 ident = l2cap_get_ident(chan->conn);
4537 chan->ident = ident;
4538
4539 req.icid = cpu_to_le16(chan->scid);
4540 req.dest_amp_id = dest_amp_id;
4541
4542 l2cap_send_cmd(chan->conn, ident, L2CAP_MOVE_CHAN_REQ, sizeof(req),
4543 &req);
4544
4545 __set_chan_timer(chan, L2CAP_MOVE_TIMEOUT);
4546 }
4547
4548 static void l2cap_send_move_chan_rsp(struct l2cap_chan *chan, u16 result)
4549 {
4550 struct l2cap_move_chan_rsp rsp;
4551
4552 BT_DBG("chan %p, result 0x%4.4x", chan, result);
4553
4554 rsp.icid = cpu_to_le16(chan->dcid);
4555 rsp.result = cpu_to_le16(result);
4556
4557 l2cap_send_cmd(chan->conn, chan->ident, L2CAP_MOVE_CHAN_RSP,
4558 sizeof(rsp), &rsp);
4559 }
4560
4561 static void l2cap_send_move_chan_cfm(struct l2cap_chan *chan, u16 result)
4562 {
4563 struct l2cap_move_chan_cfm cfm;
4564
4565 BT_DBG("chan %p, result 0x%4.4x", chan, result);
4566
4567 chan->ident = l2cap_get_ident(chan->conn);
4568
4569 cfm.icid = cpu_to_le16(chan->scid);
4570 cfm.result = cpu_to_le16(result);
4571
4572 l2cap_send_cmd(chan->conn, chan->ident, L2CAP_MOVE_CHAN_CFM,
4573 sizeof(cfm), &cfm);
4574
4575 __set_chan_timer(chan, L2CAP_MOVE_TIMEOUT);
4576 }
4577
4578 static void l2cap_send_move_chan_cfm_icid(struct l2cap_conn *conn, u16 icid)
4579 {
4580 struct l2cap_move_chan_cfm cfm;
4581
4582 BT_DBG("conn %p, icid 0x%4.4x", conn, icid);
4583
4584 cfm.icid = cpu_to_le16(icid);
4585 cfm.result = cpu_to_le16(L2CAP_MC_UNCONFIRMED);
4586
4587 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_MOVE_CHAN_CFM,
4588 sizeof(cfm), &cfm);
4589 }
4590
4591 static void l2cap_send_move_chan_cfm_rsp(struct l2cap_conn *conn, u8 ident,
4592 u16 icid)
4593 {
4594 struct l2cap_move_chan_cfm_rsp rsp;
4595
4596 BT_DBG("icid 0x%4.4x", icid);
4597
4598 rsp.icid = cpu_to_le16(icid);
4599 l2cap_send_cmd(conn, ident, L2CAP_MOVE_CHAN_CFM_RSP, sizeof(rsp), &rsp);
4600 }
4601
4602 static void __release_logical_link(struct l2cap_chan *chan)
4603 {
4604 chan->hs_hchan = NULL;
4605 chan->hs_hcon = NULL;
4606
4607 /* Placeholder - release the logical link */
4608 }
4609
4610 static void l2cap_logical_fail(struct l2cap_chan *chan)
4611 {
4612 /* Logical link setup failed */
4613 if (chan->state != BT_CONNECTED) {
4614 /* Create channel failure, disconnect */
4615 l2cap_send_disconn_req(chan, ECONNRESET);
4616 return;
4617 }
4618
4619 switch (chan->move_role) {
4620 case L2CAP_MOVE_ROLE_RESPONDER:
4621 l2cap_move_done(chan);
4622 l2cap_send_move_chan_rsp(chan, L2CAP_MR_NOT_SUPP);
4623 break;
4624 case L2CAP_MOVE_ROLE_INITIATOR:
4625 if (chan->move_state == L2CAP_MOVE_WAIT_LOGICAL_COMP ||
4626 chan->move_state == L2CAP_MOVE_WAIT_LOGICAL_CFM) {
4627 /* Remote has only sent pending or
4628 * success responses, clean up
4629 */
4630 l2cap_move_done(chan);
4631 }
4632
4633 /* Other amp move states imply that the move
4634 * has already aborted
4635 */
4636 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
4637 break;
4638 }
4639 }
4640
4641 static void l2cap_logical_finish_create(struct l2cap_chan *chan,
4642 struct hci_chan *hchan)
4643 {
4644 struct l2cap_conf_rsp rsp;
4645
4646 chan->hs_hchan = hchan;
4647 chan->hs_hcon->l2cap_data = chan->conn;
4648
4649 l2cap_send_efs_conf_rsp(chan, &rsp, chan->ident, 0);
4650
4651 if (test_bit(CONF_INPUT_DONE, &chan->conf_state)) {
4652 int err;
4653
4654 set_default_fcs(chan);
4655
4656 err = l2cap_ertm_init(chan);
4657 if (err < 0)
4658 l2cap_send_disconn_req(chan, -err);
4659 else
4660 l2cap_chan_ready(chan);
4661 }
4662 }
4663
4664 static void l2cap_logical_finish_move(struct l2cap_chan *chan,
4665 struct hci_chan *hchan)
4666 {
4667 chan->hs_hcon = hchan->conn;
4668 chan->hs_hcon->l2cap_data = chan->conn;
4669
4670 BT_DBG("move_state %d", chan->move_state);
4671
4672 switch (chan->move_state) {
4673 case L2CAP_MOVE_WAIT_LOGICAL_COMP:
4674 /* Move confirm will be sent after a success
4675 * response is received
4676 */
4677 chan->move_state = L2CAP_MOVE_WAIT_RSP_SUCCESS;
4678 break;
4679 case L2CAP_MOVE_WAIT_LOGICAL_CFM:
4680 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
4681 chan->move_state = L2CAP_MOVE_WAIT_LOCAL_BUSY;
4682 } else if (chan->move_role == L2CAP_MOVE_ROLE_INITIATOR) {
4683 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM_RSP;
4684 l2cap_send_move_chan_cfm(chan, L2CAP_MC_CONFIRMED);
4685 } else if (chan->move_role == L2CAP_MOVE_ROLE_RESPONDER) {
4686 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM;
4687 l2cap_send_move_chan_rsp(chan, L2CAP_MR_SUCCESS);
4688 }
4689 break;
4690 default:
4691 /* Move was not in expected state, free the channel */
4692 __release_logical_link(chan);
4693
4694 chan->move_state = L2CAP_MOVE_STABLE;
4695 }
4696 }
4697
4698 /* Call with chan locked */
4699 void l2cap_logical_cfm(struct l2cap_chan *chan, struct hci_chan *hchan,
4700 u8 status)
4701 {
4702 BT_DBG("chan %p, hchan %p, status %d", chan, hchan, status);
4703
4704 if (status) {
4705 l2cap_logical_fail(chan);
4706 __release_logical_link(chan);
4707 return;
4708 }
4709
4710 if (chan->state != BT_CONNECTED) {
4711 /* Ignore logical link if channel is on BR/EDR */
4712 if (chan->local_amp_id != AMP_ID_BREDR)
4713 l2cap_logical_finish_create(chan, hchan);
4714 } else {
4715 l2cap_logical_finish_move(chan, hchan);
4716 }
4717 }
4718
4719 void l2cap_move_start(struct l2cap_chan *chan)
4720 {
4721 BT_DBG("chan %p", chan);
4722
4723 if (chan->local_amp_id == AMP_ID_BREDR) {
4724 if (chan->chan_policy != BT_CHANNEL_POLICY_AMP_PREFERRED)
4725 return;
4726 chan->move_role = L2CAP_MOVE_ROLE_INITIATOR;
4727 chan->move_state = L2CAP_MOVE_WAIT_PREPARE;
4728 /* Placeholder - start physical link setup */
4729 } else {
4730 chan->move_role = L2CAP_MOVE_ROLE_INITIATOR;
4731 chan->move_state = L2CAP_MOVE_WAIT_RSP_SUCCESS;
4732 chan->move_id = 0;
4733 l2cap_move_setup(chan);
4734 l2cap_send_move_chan_req(chan, 0);
4735 }
4736 }
4737
4738 static void l2cap_do_create(struct l2cap_chan *chan, int result,
4739 u8 local_amp_id, u8 remote_amp_id)
4740 {
4741 BT_DBG("chan %p state %s %u -> %u", chan, state_to_string(chan->state),
4742 local_amp_id, remote_amp_id);
4743
4744 chan->fcs = L2CAP_FCS_NONE;
4745
4746 /* Outgoing channel on AMP */
4747 if (chan->state == BT_CONNECT) {
4748 if (result == L2CAP_CR_SUCCESS) {
4749 chan->local_amp_id = local_amp_id;
4750 l2cap_send_create_chan_req(chan, remote_amp_id);
4751 } else {
4752 /* Revert to BR/EDR connect */
4753 l2cap_send_conn_req(chan);
4754 }
4755
4756 return;
4757 }
4758
4759 /* Incoming channel on AMP */
4760 if (__l2cap_no_conn_pending(chan)) {
4761 struct l2cap_conn_rsp rsp;
4762 char buf[128];
4763 rsp.scid = cpu_to_le16(chan->dcid);
4764 rsp.dcid = cpu_to_le16(chan->scid);
4765
4766 if (result == L2CAP_CR_SUCCESS) {
4767 /* Send successful response */
4768 rsp.result = cpu_to_le16(L2CAP_CR_SUCCESS);
4769 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
4770 } else {
4771 /* Send negative response */
4772 rsp.result = cpu_to_le16(L2CAP_CR_NO_MEM);
4773 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
4774 }
4775
4776 l2cap_send_cmd(chan->conn, chan->ident, L2CAP_CREATE_CHAN_RSP,
4777 sizeof(rsp), &rsp);
4778
4779 if (result == L2CAP_CR_SUCCESS) {
4780 l2cap_state_change(chan, BT_CONFIG);
4781 set_bit(CONF_REQ_SENT, &chan->conf_state);
4782 l2cap_send_cmd(chan->conn, l2cap_get_ident(chan->conn),
4783 L2CAP_CONF_REQ,
4784 l2cap_build_conf_req(chan, buf), buf);
4785 chan->num_conf_req++;
4786 }
4787 }
4788 }
4789
4790 static void l2cap_do_move_initiate(struct l2cap_chan *chan, u8 local_amp_id,
4791 u8 remote_amp_id)
4792 {
4793 l2cap_move_setup(chan);
4794 chan->move_id = local_amp_id;
4795 chan->move_state = L2CAP_MOVE_WAIT_RSP;
4796
4797 l2cap_send_move_chan_req(chan, remote_amp_id);
4798 }
4799
4800 static void l2cap_do_move_respond(struct l2cap_chan *chan, int result)
4801 {
4802 struct hci_chan *hchan = NULL;
4803
4804 /* Placeholder - get hci_chan for logical link */
4805
4806 if (hchan) {
4807 if (hchan->state == BT_CONNECTED) {
4808 /* Logical link is ready to go */
4809 chan->hs_hcon = hchan->conn;
4810 chan->hs_hcon->l2cap_data = chan->conn;
4811 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM;
4812 l2cap_send_move_chan_rsp(chan, L2CAP_MR_SUCCESS);
4813
4814 l2cap_logical_cfm(chan, hchan, L2CAP_MR_SUCCESS);
4815 } else {
4816 /* Wait for logical link to be ready */
4817 chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_CFM;
4818 }
4819 } else {
4820 /* Logical link not available */
4821 l2cap_send_move_chan_rsp(chan, L2CAP_MR_NOT_ALLOWED);
4822 }
4823 }
4824
4825 static void l2cap_do_move_cancel(struct l2cap_chan *chan, int result)
4826 {
4827 if (chan->move_role == L2CAP_MOVE_ROLE_RESPONDER) {
4828 u8 rsp_result;
4829 if (result == -EINVAL)
4830 rsp_result = L2CAP_MR_BAD_ID;
4831 else
4832 rsp_result = L2CAP_MR_NOT_ALLOWED;
4833
4834 l2cap_send_move_chan_rsp(chan, rsp_result);
4835 }
4836
4837 chan->move_role = L2CAP_MOVE_ROLE_NONE;
4838 chan->move_state = L2CAP_MOVE_STABLE;
4839
4840 /* Restart data transmission */
4841 l2cap_ertm_send(chan);
4842 }
4843
4844 /* Invoke with locked chan */
4845 void __l2cap_physical_cfm(struct l2cap_chan *chan, int result)
4846 {
4847 u8 local_amp_id = chan->local_amp_id;
4848 u8 remote_amp_id = chan->remote_amp_id;
4849
4850 BT_DBG("chan %p, result %d, local_amp_id %d, remote_amp_id %d",
4851 chan, result, local_amp_id, remote_amp_id);
4852
4853 if (chan->state == BT_DISCONN || chan->state == BT_CLOSED) {
4854 l2cap_chan_unlock(chan);
4855 return;
4856 }
4857
4858 if (chan->state != BT_CONNECTED) {
4859 l2cap_do_create(chan, result, local_amp_id, remote_amp_id);
4860 } else if (result != L2CAP_MR_SUCCESS) {
4861 l2cap_do_move_cancel(chan, result);
4862 } else {
4863 switch (chan->move_role) {
4864 case L2CAP_MOVE_ROLE_INITIATOR:
4865 l2cap_do_move_initiate(chan, local_amp_id,
4866 remote_amp_id);
4867 break;
4868 case L2CAP_MOVE_ROLE_RESPONDER:
4869 l2cap_do_move_respond(chan, result);
4870 break;
4871 default:
4872 l2cap_do_move_cancel(chan, result);
4873 break;
4874 }
4875 }
4876 }
4877
4878 static inline int l2cap_move_channel_req(struct l2cap_conn *conn,
4879 struct l2cap_cmd_hdr *cmd,
4880 u16 cmd_len, void *data)
4881 {
4882 struct l2cap_move_chan_req *req = data;
4883 struct l2cap_move_chan_rsp rsp;
4884 struct l2cap_chan *chan;
4885 u16 icid = 0;
4886 u16 result = L2CAP_MR_NOT_ALLOWED;
4887
4888 if (cmd_len != sizeof(*req))
4889 return -EPROTO;
4890
4891 icid = le16_to_cpu(req->icid);
4892
4893 BT_DBG("icid 0x%4.4x, dest_amp_id %d", icid, req->dest_amp_id);
4894
4895 if (!(conn->local_fixed_chan & L2CAP_FC_A2MP))
4896 return -EINVAL;
4897
4898 chan = l2cap_get_chan_by_dcid(conn, icid);
4899 if (!chan) {
4900 rsp.icid = cpu_to_le16(icid);
4901 rsp.result = cpu_to_le16(L2CAP_MR_NOT_ALLOWED);
4902 l2cap_send_cmd(conn, cmd->ident, L2CAP_MOVE_CHAN_RSP,
4903 sizeof(rsp), &rsp);
4904 return 0;
4905 }
4906
4907 chan->ident = cmd->ident;
4908
4909 if (chan->scid < L2CAP_CID_DYN_START ||
4910 chan->chan_policy == BT_CHANNEL_POLICY_BREDR_ONLY ||
4911 (chan->mode != L2CAP_MODE_ERTM &&
4912 chan->mode != L2CAP_MODE_STREAMING)) {
4913 result = L2CAP_MR_NOT_ALLOWED;
4914 goto send_move_response;
4915 }
4916
4917 if (chan->local_amp_id == req->dest_amp_id) {
4918 result = L2CAP_MR_SAME_ID;
4919 goto send_move_response;
4920 }
4921
4922 if (req->dest_amp_id != AMP_ID_BREDR) {
4923 struct hci_dev *hdev;
4924 hdev = hci_dev_get(req->dest_amp_id);
4925 if (!hdev || hdev->dev_type != HCI_AMP ||
4926 !test_bit(HCI_UP, &hdev->flags)) {
4927 if (hdev)
4928 hci_dev_put(hdev);
4929
4930 result = L2CAP_MR_BAD_ID;
4931 goto send_move_response;
4932 }
4933 hci_dev_put(hdev);
4934 }
4935
4936 /* Detect a move collision. Only send a collision response
4937 * if this side has "lost", otherwise proceed with the move.
4938 * The winner has the larger bd_addr.
4939 */
4940 if ((__chan_is_moving(chan) ||
4941 chan->move_role != L2CAP_MOVE_ROLE_NONE) &&
4942 bacmp(&conn->hcon->src, &conn->hcon->dst) > 0) {
4943 result = L2CAP_MR_COLLISION;
4944 goto send_move_response;
4945 }
4946
4947 chan->move_role = L2CAP_MOVE_ROLE_RESPONDER;
4948 l2cap_move_setup(chan);
4949 chan->move_id = req->dest_amp_id;
4950 icid = chan->dcid;
4951
4952 if (req->dest_amp_id == AMP_ID_BREDR) {
4953 /* Moving to BR/EDR */
4954 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
4955 chan->move_state = L2CAP_MOVE_WAIT_LOCAL_BUSY;
4956 result = L2CAP_MR_PEND;
4957 } else {
4958 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM;
4959 result = L2CAP_MR_SUCCESS;
4960 }
4961 } else {
4962 chan->move_state = L2CAP_MOVE_WAIT_PREPARE;
4963 /* Placeholder - uncomment when amp functions are available */
4964 /*amp_accept_physical(chan, req->dest_amp_id);*/
4965 result = L2CAP_MR_PEND;
4966 }
4967
4968 send_move_response:
4969 l2cap_send_move_chan_rsp(chan, result);
4970
4971 l2cap_chan_unlock(chan);
4972
4973 return 0;
4974 }
4975
4976 static void l2cap_move_continue(struct l2cap_conn *conn, u16 icid, u16 result)
4977 {
4978 struct l2cap_chan *chan;
4979 struct hci_chan *hchan = NULL;
4980
4981 chan = l2cap_get_chan_by_scid(conn, icid);
4982 if (!chan) {
4983 l2cap_send_move_chan_cfm_icid(conn, icid);
4984 return;
4985 }
4986
4987 __clear_chan_timer(chan);
4988 if (result == L2CAP_MR_PEND)
4989 __set_chan_timer(chan, L2CAP_MOVE_ERTX_TIMEOUT);
4990
4991 switch (chan->move_state) {
4992 case L2CAP_MOVE_WAIT_LOGICAL_COMP:
4993 /* Move confirm will be sent when logical link
4994 * is complete.
4995 */
4996 chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_CFM;
4997 break;
4998 case L2CAP_MOVE_WAIT_RSP_SUCCESS:
4999 if (result == L2CAP_MR_PEND) {
5000 break;
5001 } else if (test_bit(CONN_LOCAL_BUSY,
5002 &chan->conn_state)) {
5003 chan->move_state = L2CAP_MOVE_WAIT_LOCAL_BUSY;
5004 } else {
5005 /* Logical link is up or moving to BR/EDR,
5006 * proceed with move
5007 */
5008 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM_RSP;
5009 l2cap_send_move_chan_cfm(chan, L2CAP_MC_CONFIRMED);
5010 }
5011 break;
5012 case L2CAP_MOVE_WAIT_RSP:
5013 /* Moving to AMP */
5014 if (result == L2CAP_MR_SUCCESS) {
5015 /* Remote is ready, send confirm immediately
5016 * after logical link is ready
5017 */
5018 chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_CFM;
5019 } else {
5020 /* Both logical link and move success
5021 * are required to confirm
5022 */
5023 chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_COMP;
5024 }
5025
5026 /* Placeholder - get hci_chan for logical link */
5027 if (!hchan) {
5028 /* Logical link not available */
5029 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
5030 break;
5031 }
5032
5033 /* If the logical link is not yet connected, do not
5034 * send confirmation.
5035 */
5036 if (hchan->state != BT_CONNECTED)
5037 break;
5038
5039 /* Logical link is already ready to go */
5040
5041 chan->hs_hcon = hchan->conn;
5042 chan->hs_hcon->l2cap_data = chan->conn;
5043
5044 if (result == L2CAP_MR_SUCCESS) {
5045 /* Can confirm now */
5046 l2cap_send_move_chan_cfm(chan, L2CAP_MC_CONFIRMED);
5047 } else {
5048 /* Now only need move success
5049 * to confirm
5050 */
5051 chan->move_state = L2CAP_MOVE_WAIT_RSP_SUCCESS;
5052 }
5053
5054 l2cap_logical_cfm(chan, hchan, L2CAP_MR_SUCCESS);
5055 break;
5056 default:
5057 /* Any other amp move state means the move failed. */
5058 chan->move_id = chan->local_amp_id;
5059 l2cap_move_done(chan);
5060 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
5061 }
5062
5063 l2cap_chan_unlock(chan);
5064 }
5065
5066 static void l2cap_move_fail(struct l2cap_conn *conn, u8 ident, u16 icid,
5067 u16 result)
5068 {
5069 struct l2cap_chan *chan;
5070
5071 chan = l2cap_get_chan_by_ident(conn, ident);
5072 if (!chan) {
5073 /* Could not locate channel, icid is best guess */
5074 l2cap_send_move_chan_cfm_icid(conn, icid);
5075 return;
5076 }
5077
5078 __clear_chan_timer(chan);
5079
5080 if (chan->move_role == L2CAP_MOVE_ROLE_INITIATOR) {
5081 if (result == L2CAP_MR_COLLISION) {
5082 chan->move_role = L2CAP_MOVE_ROLE_RESPONDER;
5083 } else {
5084 /* Cleanup - cancel move */
5085 chan->move_id = chan->local_amp_id;
5086 l2cap_move_done(chan);
5087 }
5088 }
5089
5090 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
5091
5092 l2cap_chan_unlock(chan);
5093 }
5094
5095 static int l2cap_move_channel_rsp(struct l2cap_conn *conn,
5096 struct l2cap_cmd_hdr *cmd,
5097 u16 cmd_len, void *data)
5098 {
5099 struct l2cap_move_chan_rsp *rsp = data;
5100 u16 icid, result;
5101
5102 if (cmd_len != sizeof(*rsp))
5103 return -EPROTO;
5104
5105 icid = le16_to_cpu(rsp->icid);
5106 result = le16_to_cpu(rsp->result);
5107
5108 BT_DBG("icid 0x%4.4x, result 0x%4.4x", icid, result);
5109
5110 if (result == L2CAP_MR_SUCCESS || result == L2CAP_MR_PEND)
5111 l2cap_move_continue(conn, icid, result);
5112 else
5113 l2cap_move_fail(conn, cmd->ident, icid, result);
5114
5115 return 0;
5116 }
5117
5118 static int l2cap_move_channel_confirm(struct l2cap_conn *conn,
5119 struct l2cap_cmd_hdr *cmd,
5120 u16 cmd_len, void *data)
5121 {
5122 struct l2cap_move_chan_cfm *cfm = data;
5123 struct l2cap_chan *chan;
5124 u16 icid, result;
5125
5126 if (cmd_len != sizeof(*cfm))
5127 return -EPROTO;
5128
5129 icid = le16_to_cpu(cfm->icid);
5130 result = le16_to_cpu(cfm->result);
5131
5132 BT_DBG("icid 0x%4.4x, result 0x%4.4x", icid, result);
5133
5134 chan = l2cap_get_chan_by_dcid(conn, icid);
5135 if (!chan) {
5136 /* Spec requires a response even if the icid was not found */
5137 l2cap_send_move_chan_cfm_rsp(conn, cmd->ident, icid);
5138 return 0;
5139 }
5140
5141 if (chan->move_state == L2CAP_MOVE_WAIT_CONFIRM) {
5142 if (result == L2CAP_MC_CONFIRMED) {
5143 chan->local_amp_id = chan->move_id;
5144 if (chan->local_amp_id == AMP_ID_BREDR)
5145 __release_logical_link(chan);
5146 } else {
5147 chan->move_id = chan->local_amp_id;
5148 }
5149
5150 l2cap_move_done(chan);
5151 }
5152
5153 l2cap_send_move_chan_cfm_rsp(conn, cmd->ident, icid);
5154
5155 l2cap_chan_unlock(chan);
5156
5157 return 0;
5158 }
5159
5160 static inline int l2cap_move_channel_confirm_rsp(struct l2cap_conn *conn,
5161 struct l2cap_cmd_hdr *cmd,
5162 u16 cmd_len, void *data)
5163 {
5164 struct l2cap_move_chan_cfm_rsp *rsp = data;
5165 struct l2cap_chan *chan;
5166 u16 icid;
5167
5168 if (cmd_len != sizeof(*rsp))
5169 return -EPROTO;
5170
5171 icid = le16_to_cpu(rsp->icid);
5172
5173 BT_DBG("icid 0x%4.4x", icid);
5174
5175 chan = l2cap_get_chan_by_scid(conn, icid);
5176 if (!chan)
5177 return 0;
5178
5179 __clear_chan_timer(chan);
5180
5181 if (chan->move_state == L2CAP_MOVE_WAIT_CONFIRM_RSP) {
5182 chan->local_amp_id = chan->move_id;
5183
5184 if (chan->local_amp_id == AMP_ID_BREDR && chan->hs_hchan)
5185 __release_logical_link(chan);
5186
5187 l2cap_move_done(chan);
5188 }
5189
5190 l2cap_chan_unlock(chan);
5191
5192 return 0;
5193 }
5194
5195 static inline int l2cap_conn_param_update_req(struct l2cap_conn *conn,
5196 struct l2cap_cmd_hdr *cmd,
5197 u16 cmd_len, u8 *data)
5198 {
5199 struct hci_conn *hcon = conn->hcon;
5200 struct l2cap_conn_param_update_req *req;
5201 struct l2cap_conn_param_update_rsp rsp;
5202 u16 min, max, latency, to_multiplier;
5203 int err;
5204
5205 if (hcon->role != HCI_ROLE_MASTER)
5206 return -EINVAL;
5207
5208 if (cmd_len != sizeof(struct l2cap_conn_param_update_req))
5209 return -EPROTO;
5210
5211 req = (struct l2cap_conn_param_update_req *) data;
5212 min = __le16_to_cpu(req->min);
5213 max = __le16_to_cpu(req->max);
5214 latency = __le16_to_cpu(req->latency);
5215 to_multiplier = __le16_to_cpu(req->to_multiplier);
5216
5217 BT_DBG("min 0x%4.4x max 0x%4.4x latency: 0x%4.4x Timeout: 0x%4.4x",
5218 min, max, latency, to_multiplier);
5219
5220 memset(&rsp, 0, sizeof(rsp));
5221
5222 err = hci_check_conn_params(min, max, latency, to_multiplier);
5223 if (err)
5224 rsp.result = cpu_to_le16(L2CAP_CONN_PARAM_REJECTED);
5225 else
5226 rsp.result = cpu_to_le16(L2CAP_CONN_PARAM_ACCEPTED);
5227
5228 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONN_PARAM_UPDATE_RSP,
5229 sizeof(rsp), &rsp);
5230
5231 if (!err) {
5232 u8 store_hint;
5233
5234 store_hint = hci_le_conn_update(hcon, min, max, latency,
5235 to_multiplier);
5236 mgmt_new_conn_param(hcon->hdev, &hcon->dst, hcon->dst_type,
5237 store_hint, min, max, latency,
5238 to_multiplier);
5239
5240 }
5241
5242 return 0;
5243 }
5244
5245 static int l2cap_le_connect_rsp(struct l2cap_conn *conn,
5246 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5247 u8 *data)
5248 {
5249 struct l2cap_le_conn_rsp *rsp = (struct l2cap_le_conn_rsp *) data;
5250 struct hci_conn *hcon = conn->hcon;
5251 u16 dcid, mtu, mps, credits, result;
5252 struct l2cap_chan *chan;
5253 int err, sec_level;
5254
5255 if (cmd_len < sizeof(*rsp))
5256 return -EPROTO;
5257
5258 dcid = __le16_to_cpu(rsp->dcid);
5259 mtu = __le16_to_cpu(rsp->mtu);
5260 mps = __le16_to_cpu(rsp->mps);
5261 credits = __le16_to_cpu(rsp->credits);
5262 result = __le16_to_cpu(rsp->result);
5263
5264 if (result == L2CAP_CR_SUCCESS && (mtu < 23 || mps < 23 ||
5265 dcid < L2CAP_CID_DYN_START ||
5266 dcid > L2CAP_CID_LE_DYN_END))
5267 return -EPROTO;
5268
5269 BT_DBG("dcid 0x%4.4x mtu %u mps %u credits %u result 0x%2.2x",
5270 dcid, mtu, mps, credits, result);
5271
5272 mutex_lock(&conn->chan_lock);
5273
5274 chan = __l2cap_get_chan_by_ident(conn, cmd->ident);
5275 if (!chan) {
5276 err = -EBADSLT;
5277 goto unlock;
5278 }
5279
5280 err = 0;
5281
5282 l2cap_chan_lock(chan);
5283
5284 switch (result) {
5285 case L2CAP_CR_SUCCESS:
5286 if (__l2cap_get_chan_by_dcid(conn, dcid)) {
5287 err = -EBADSLT;
5288 break;
5289 }
5290
5291 chan->ident = 0;
5292 chan->dcid = dcid;
5293 chan->omtu = mtu;
5294 chan->remote_mps = mps;
5295 chan->tx_credits = credits;
5296 l2cap_chan_ready(chan);
5297 break;
5298
5299 case L2CAP_CR_AUTHENTICATION:
5300 case L2CAP_CR_ENCRYPTION:
5301 /* If we already have MITM protection we can't do
5302 * anything.
5303 */
5304 if (hcon->sec_level > BT_SECURITY_MEDIUM) {
5305 l2cap_chan_del(chan, ECONNREFUSED);
5306 break;
5307 }
5308
5309 sec_level = hcon->sec_level + 1;
5310 if (chan->sec_level < sec_level)
5311 chan->sec_level = sec_level;
5312
5313 /* We'll need to send a new Connect Request */
5314 clear_bit(FLAG_LE_CONN_REQ_SENT, &chan->flags);
5315
5316 smp_conn_security(hcon, chan->sec_level);
5317 break;
5318
5319 default:
5320 l2cap_chan_del(chan, ECONNREFUSED);
5321 break;
5322 }
5323
5324 l2cap_chan_unlock(chan);
5325
5326 unlock:
5327 mutex_unlock(&conn->chan_lock);
5328
5329 return err;
5330 }
5331
5332 static inline int l2cap_bredr_sig_cmd(struct l2cap_conn *conn,
5333 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5334 u8 *data)
5335 {
5336 int err = 0;
5337
5338 switch (cmd->code) {
5339 case L2CAP_COMMAND_REJ:
5340 l2cap_command_rej(conn, cmd, cmd_len, data);
5341 break;
5342
5343 case L2CAP_CONN_REQ:
5344 err = l2cap_connect_req(conn, cmd, cmd_len, data);
5345 break;
5346
5347 case L2CAP_CONN_RSP:
5348 case L2CAP_CREATE_CHAN_RSP:
5349 l2cap_connect_create_rsp(conn, cmd, cmd_len, data);
5350 break;
5351
5352 case L2CAP_CONF_REQ:
5353 err = l2cap_config_req(conn, cmd, cmd_len, data);
5354 break;
5355
5356 case L2CAP_CONF_RSP:
5357 l2cap_config_rsp(conn, cmd, cmd_len, data);
5358 break;
5359
5360 case L2CAP_DISCONN_REQ:
5361 err = l2cap_disconnect_req(conn, cmd, cmd_len, data);
5362 break;
5363
5364 case L2CAP_DISCONN_RSP:
5365 l2cap_disconnect_rsp(conn, cmd, cmd_len, data);
5366 break;
5367
5368 case L2CAP_ECHO_REQ:
5369 l2cap_send_cmd(conn, cmd->ident, L2CAP_ECHO_RSP, cmd_len, data);
5370 break;
5371
5372 case L2CAP_ECHO_RSP:
5373 break;
5374
5375 case L2CAP_INFO_REQ:
5376 err = l2cap_information_req(conn, cmd, cmd_len, data);
5377 break;
5378
5379 case L2CAP_INFO_RSP:
5380 l2cap_information_rsp(conn, cmd, cmd_len, data);
5381 break;
5382
5383 case L2CAP_CREATE_CHAN_REQ:
5384 err = l2cap_create_channel_req(conn, cmd, cmd_len, data);
5385 break;
5386
5387 case L2CAP_MOVE_CHAN_REQ:
5388 err = l2cap_move_channel_req(conn, cmd, cmd_len, data);
5389 break;
5390
5391 case L2CAP_MOVE_CHAN_RSP:
5392 l2cap_move_channel_rsp(conn, cmd, cmd_len, data);
5393 break;
5394
5395 case L2CAP_MOVE_CHAN_CFM:
5396 err = l2cap_move_channel_confirm(conn, cmd, cmd_len, data);
5397 break;
5398
5399 case L2CAP_MOVE_CHAN_CFM_RSP:
5400 l2cap_move_channel_confirm_rsp(conn, cmd, cmd_len, data);
5401 break;
5402
5403 default:
5404 BT_ERR("Unknown BR/EDR signaling command 0x%2.2x", cmd->code);
5405 err = -EINVAL;
5406 break;
5407 }
5408
5409 return err;
5410 }
5411
5412 static int l2cap_le_connect_req(struct l2cap_conn *conn,
5413 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5414 u8 *data)
5415 {
5416 struct l2cap_le_conn_req *req = (struct l2cap_le_conn_req *) data;
5417 struct l2cap_le_conn_rsp rsp;
5418 struct l2cap_chan *chan, *pchan;
5419 u16 dcid, scid, credits, mtu, mps;
5420 __le16 psm;
5421 u8 result;
5422
5423 if (cmd_len != sizeof(*req))
5424 return -EPROTO;
5425
5426 scid = __le16_to_cpu(req->scid);
5427 mtu = __le16_to_cpu(req->mtu);
5428 mps = __le16_to_cpu(req->mps);
5429 psm = req->psm;
5430 dcid = 0;
5431 credits = 0;
5432
5433 if (mtu < 23 || mps < 23)
5434 return -EPROTO;
5435
5436 BT_DBG("psm 0x%2.2x scid 0x%4.4x mtu %u mps %u", __le16_to_cpu(psm),
5437 scid, mtu, mps);
5438
5439 /* Check if we have socket listening on psm */
5440 pchan = l2cap_global_chan_by_psm(BT_LISTEN, psm, &conn->hcon->src,
5441 &conn->hcon->dst, LE_LINK);
5442 if (!pchan) {
5443 result = L2CAP_CR_BAD_PSM;
5444 chan = NULL;
5445 goto response;
5446 }
5447
5448 mutex_lock(&conn->chan_lock);
5449 l2cap_chan_lock(pchan);
5450
5451 if (!smp_sufficient_security(conn->hcon, pchan->sec_level,
5452 SMP_ALLOW_STK)) {
5453 result = L2CAP_CR_AUTHENTICATION;
5454 chan = NULL;
5455 goto response_unlock;
5456 }
5457
5458 /* Check for valid dynamic CID range */
5459 if (scid < L2CAP_CID_DYN_START || scid > L2CAP_CID_LE_DYN_END) {
5460 result = L2CAP_CR_INVALID_SCID;
5461 chan = NULL;
5462 goto response_unlock;
5463 }
5464
5465 /* Check if we already have channel with that dcid */
5466 if (__l2cap_get_chan_by_dcid(conn, scid)) {
5467 result = L2CAP_CR_SCID_IN_USE;
5468 chan = NULL;
5469 goto response_unlock;
5470 }
5471
5472 chan = pchan->ops->new_connection(pchan);
5473 if (!chan) {
5474 result = L2CAP_CR_NO_MEM;
5475 goto response_unlock;
5476 }
5477
5478 l2cap_le_flowctl_init(chan);
5479
5480 bacpy(&chan->src, &conn->hcon->src);
5481 bacpy(&chan->dst, &conn->hcon->dst);
5482 chan->src_type = bdaddr_src_type(conn->hcon);
5483 chan->dst_type = bdaddr_dst_type(conn->hcon);
5484 chan->psm = psm;
5485 chan->dcid = scid;
5486 chan->omtu = mtu;
5487 chan->remote_mps = mps;
5488 chan->tx_credits = __le16_to_cpu(req->credits);
5489
5490 __l2cap_chan_add(conn, chan);
5491 dcid = chan->scid;
5492 credits = chan->rx_credits;
5493
5494 __set_chan_timer(chan, chan->ops->get_sndtimeo(chan));
5495
5496 chan->ident = cmd->ident;
5497
5498 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) {
5499 l2cap_state_change(chan, BT_CONNECT2);
5500 /* The following result value is actually not defined
5501 * for LE CoC but we use it to let the function know
5502 * that it should bail out after doing its cleanup
5503 * instead of sending a response.
5504 */
5505 result = L2CAP_CR_PEND;
5506 chan->ops->defer(chan);
5507 } else {
5508 l2cap_chan_ready(chan);
5509 result = L2CAP_CR_SUCCESS;
5510 }
5511
5512 response_unlock:
5513 l2cap_chan_unlock(pchan);
5514 mutex_unlock(&conn->chan_lock);
5515 l2cap_chan_put(pchan);
5516
5517 if (result == L2CAP_CR_PEND)
5518 return 0;
5519
5520 response:
5521 if (chan) {
5522 rsp.mtu = cpu_to_le16(chan->imtu);
5523 rsp.mps = cpu_to_le16(chan->mps);
5524 } else {
5525 rsp.mtu = 0;
5526 rsp.mps = 0;
5527 }
5528
5529 rsp.dcid = cpu_to_le16(dcid);
5530 rsp.credits = cpu_to_le16(credits);
5531 rsp.result = cpu_to_le16(result);
5532
5533 l2cap_send_cmd(conn, cmd->ident, L2CAP_LE_CONN_RSP, sizeof(rsp), &rsp);
5534
5535 return 0;
5536 }
5537
5538 static inline int l2cap_le_credits(struct l2cap_conn *conn,
5539 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5540 u8 *data)
5541 {
5542 struct l2cap_le_credits *pkt;
5543 struct l2cap_chan *chan;
5544 u16 cid, credits, max_credits;
5545
5546 if (cmd_len != sizeof(*pkt))
5547 return -EPROTO;
5548
5549 pkt = (struct l2cap_le_credits *) data;
5550 cid = __le16_to_cpu(pkt->cid);
5551 credits = __le16_to_cpu(pkt->credits);
5552
5553 BT_DBG("cid 0x%4.4x credits 0x%4.4x", cid, credits);
5554
5555 chan = l2cap_get_chan_by_dcid(conn, cid);
5556 if (!chan)
5557 return -EBADSLT;
5558
5559 max_credits = LE_FLOWCTL_MAX_CREDITS - chan->tx_credits;
5560 if (credits > max_credits) {
5561 BT_ERR("LE credits overflow");
5562 l2cap_send_disconn_req(chan, ECONNRESET);
5563 l2cap_chan_unlock(chan);
5564
5565 /* Return 0 so that we don't trigger an unnecessary
5566 * command reject packet.
5567 */
5568 return 0;
5569 }
5570
5571 chan->tx_credits += credits;
5572
5573 while (chan->tx_credits && !skb_queue_empty(&chan->tx_q)) {
5574 l2cap_do_send(chan, skb_dequeue(&chan->tx_q));
5575 chan->tx_credits--;
5576 }
5577
5578 if (chan->tx_credits)
5579 chan->ops->resume(chan);
5580
5581 l2cap_chan_unlock(chan);
5582
5583 return 0;
5584 }
5585
5586 static inline int l2cap_le_command_rej(struct l2cap_conn *conn,
5587 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5588 u8 *data)
5589 {
5590 struct l2cap_cmd_rej_unk *rej = (struct l2cap_cmd_rej_unk *) data;
5591 struct l2cap_chan *chan;
5592
5593 if (cmd_len < sizeof(*rej))
5594 return -EPROTO;
5595
5596 mutex_lock(&conn->chan_lock);
5597
5598 chan = __l2cap_get_chan_by_ident(conn, cmd->ident);
5599 if (!chan)
5600 goto done;
5601
5602 l2cap_chan_lock(chan);
5603 l2cap_chan_del(chan, ECONNREFUSED);
5604 l2cap_chan_unlock(chan);
5605
5606 done:
5607 mutex_unlock(&conn->chan_lock);
5608 return 0;
5609 }
5610
5611 static inline int l2cap_le_sig_cmd(struct l2cap_conn *conn,
5612 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5613 u8 *data)
5614 {
5615 int err = 0;
5616
5617 switch (cmd->code) {
5618 case L2CAP_COMMAND_REJ:
5619 l2cap_le_command_rej(conn, cmd, cmd_len, data);
5620 break;
5621
5622 case L2CAP_CONN_PARAM_UPDATE_REQ:
5623 err = l2cap_conn_param_update_req(conn, cmd, cmd_len, data);
5624 break;
5625
5626 case L2CAP_CONN_PARAM_UPDATE_RSP:
5627 break;
5628
5629 case L2CAP_LE_CONN_RSP:
5630 l2cap_le_connect_rsp(conn, cmd, cmd_len, data);
5631 break;
5632
5633 case L2CAP_LE_CONN_REQ:
5634 err = l2cap_le_connect_req(conn, cmd, cmd_len, data);
5635 break;
5636
5637 case L2CAP_LE_CREDITS:
5638 err = l2cap_le_credits(conn, cmd, cmd_len, data);
5639 break;
5640
5641 case L2CAP_DISCONN_REQ:
5642 err = l2cap_disconnect_req(conn, cmd, cmd_len, data);
5643 break;
5644
5645 case L2CAP_DISCONN_RSP:
5646 l2cap_disconnect_rsp(conn, cmd, cmd_len, data);
5647 break;
5648
5649 default:
5650 BT_ERR("Unknown LE signaling command 0x%2.2x", cmd->code);
5651 err = -EINVAL;
5652 break;
5653 }
5654
5655 return err;
5656 }
5657
5658 static inline void l2cap_le_sig_channel(struct l2cap_conn *conn,
5659 struct sk_buff *skb)
5660 {
5661 struct hci_conn *hcon = conn->hcon;
5662 struct l2cap_cmd_hdr *cmd;
5663 u16 len;
5664 int err;
5665
5666 if (hcon->type != LE_LINK)
5667 goto drop;
5668
5669 if (skb->len < L2CAP_CMD_HDR_SIZE)
5670 goto drop;
5671
5672 cmd = (void *) skb->data;
5673 skb_pull(skb, L2CAP_CMD_HDR_SIZE);
5674
5675 len = le16_to_cpu(cmd->len);
5676
5677 BT_DBG("code 0x%2.2x len %d id 0x%2.2x", cmd->code, len, cmd->ident);
5678
5679 if (len != skb->len || !cmd->ident) {
5680 BT_DBG("corrupted command");
5681 goto drop;
5682 }
5683
5684 err = l2cap_le_sig_cmd(conn, cmd, len, skb->data);
5685 if (err) {
5686 struct l2cap_cmd_rej_unk rej;
5687
5688 BT_ERR("Wrong link type (%d)", err);
5689
5690 rej.reason = cpu_to_le16(L2CAP_REJ_NOT_UNDERSTOOD);
5691 l2cap_send_cmd(conn, cmd->ident, L2CAP_COMMAND_REJ,
5692 sizeof(rej), &rej);
5693 }
5694
5695 drop:
5696 kfree_skb(skb);
5697 }
5698
5699 static inline void l2cap_sig_channel(struct l2cap_conn *conn,
5700 struct sk_buff *skb)
5701 {
5702 struct hci_conn *hcon = conn->hcon;
5703 u8 *data = skb->data;
5704 int len = skb->len;
5705 struct l2cap_cmd_hdr cmd;
5706 int err;
5707
5708 l2cap_raw_recv(conn, skb);
5709
5710 if (hcon->type != ACL_LINK)
5711 goto drop;
5712
5713 while (len >= L2CAP_CMD_HDR_SIZE) {
5714 u16 cmd_len;
5715 memcpy(&cmd, data, L2CAP_CMD_HDR_SIZE);
5716 data += L2CAP_CMD_HDR_SIZE;
5717 len -= L2CAP_CMD_HDR_SIZE;
5718
5719 cmd_len = le16_to_cpu(cmd.len);
5720
5721 BT_DBG("code 0x%2.2x len %d id 0x%2.2x", cmd.code, cmd_len,
5722 cmd.ident);
5723
5724 if (cmd_len > len || !cmd.ident) {
5725 BT_DBG("corrupted command");
5726 break;
5727 }
5728
5729 err = l2cap_bredr_sig_cmd(conn, &cmd, cmd_len, data);
5730 if (err) {
5731 struct l2cap_cmd_rej_unk rej;
5732
5733 BT_ERR("Wrong link type (%d)", err);
5734
5735 rej.reason = cpu_to_le16(L2CAP_REJ_NOT_UNDERSTOOD);
5736 l2cap_send_cmd(conn, cmd.ident, L2CAP_COMMAND_REJ,
5737 sizeof(rej), &rej);
5738 }
5739
5740 data += cmd_len;
5741 len -= cmd_len;
5742 }
5743
5744 drop:
5745 kfree_skb(skb);
5746 }
5747
5748 static int l2cap_check_fcs(struct l2cap_chan *chan, struct sk_buff *skb)
5749 {
5750 u16 our_fcs, rcv_fcs;
5751 int hdr_size;
5752
5753 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
5754 hdr_size = L2CAP_EXT_HDR_SIZE;
5755 else
5756 hdr_size = L2CAP_ENH_HDR_SIZE;
5757
5758 if (chan->fcs == L2CAP_FCS_CRC16) {
5759 skb_trim(skb, skb->len - L2CAP_FCS_SIZE);
5760 rcv_fcs = get_unaligned_le16(skb->data + skb->len);
5761 our_fcs = crc16(0, skb->data - hdr_size, skb->len + hdr_size);
5762
5763 if (our_fcs != rcv_fcs)
5764 return -EBADMSG;
5765 }
5766 return 0;
5767 }
5768
5769 static void l2cap_send_i_or_rr_or_rnr(struct l2cap_chan *chan)
5770 {
5771 struct l2cap_ctrl control;
5772
5773 BT_DBG("chan %p", chan);
5774
5775 memset(&control, 0, sizeof(control));
5776 control.sframe = 1;
5777 control.final = 1;
5778 control.reqseq = chan->buffer_seq;
5779 set_bit(CONN_SEND_FBIT, &chan->conn_state);
5780
5781 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
5782 control.super = L2CAP_SUPER_RNR;
5783 l2cap_send_sframe(chan, &control);
5784 }
5785
5786 if (test_and_clear_bit(CONN_REMOTE_BUSY, &chan->conn_state) &&
5787 chan->unacked_frames > 0)
5788 __set_retrans_timer(chan);
5789
5790 /* Send pending iframes */
5791 l2cap_ertm_send(chan);
5792
5793 if (!test_bit(CONN_LOCAL_BUSY, &chan->conn_state) &&
5794 test_bit(CONN_SEND_FBIT, &chan->conn_state)) {
5795 /* F-bit wasn't sent in an s-frame or i-frame yet, so
5796 * send it now.
5797 */
5798 control.super = L2CAP_SUPER_RR;
5799 l2cap_send_sframe(chan, &control);
5800 }
5801 }
5802
5803 static void append_skb_frag(struct sk_buff *skb, struct sk_buff *new_frag,
5804 struct sk_buff **last_frag)
5805 {
5806 /* skb->len reflects data in skb as well as all fragments
5807 * skb->data_len reflects only data in fragments
5808 */
5809 if (!skb_has_frag_list(skb))
5810 skb_shinfo(skb)->frag_list = new_frag;
5811
5812 new_frag->next = NULL;
5813
5814 (*last_frag)->next = new_frag;
5815 *last_frag = new_frag;
5816
5817 skb->len += new_frag->len;
5818 skb->data_len += new_frag->len;
5819 skb->truesize += new_frag->truesize;
5820 }
5821
5822 static int l2cap_reassemble_sdu(struct l2cap_chan *chan, struct sk_buff *skb,
5823 struct l2cap_ctrl *control)
5824 {
5825 int err = -EINVAL;
5826
5827 switch (control->sar) {
5828 case L2CAP_SAR_UNSEGMENTED:
5829 if (chan->sdu)
5830 break;
5831
5832 err = chan->ops->recv(chan, skb);
5833 break;
5834
5835 case L2CAP_SAR_START:
5836 if (chan->sdu)
5837 break;
5838
5839 if (!pskb_may_pull(skb, L2CAP_SDULEN_SIZE))
5840 break;
5841
5842 chan->sdu_len = get_unaligned_le16(skb->data);
5843 skb_pull(skb, L2CAP_SDULEN_SIZE);
5844
5845 if (chan->sdu_len > chan->imtu) {
5846 err = -EMSGSIZE;
5847 break;
5848 }
5849
5850 if (skb->len >= chan->sdu_len)
5851 break;
5852
5853 chan->sdu = skb;
5854 chan->sdu_last_frag = skb;
5855
5856 skb = NULL;
5857 err = 0;
5858 break;
5859
5860 case L2CAP_SAR_CONTINUE:
5861 if (!chan->sdu)
5862 break;
5863
5864 append_skb_frag(chan->sdu, skb,
5865 &chan->sdu_last_frag);
5866 skb = NULL;
5867
5868 if (chan->sdu->len >= chan->sdu_len)
5869 break;
5870
5871 err = 0;
5872 break;
5873
5874 case L2CAP_SAR_END:
5875 if (!chan->sdu)
5876 break;
5877
5878 append_skb_frag(chan->sdu, skb,
5879 &chan->sdu_last_frag);
5880 skb = NULL;
5881
5882 if (chan->sdu->len != chan->sdu_len)
5883 break;
5884
5885 err = chan->ops->recv(chan, chan->sdu);
5886
5887 if (!err) {
5888 /* Reassembly complete */
5889 chan->sdu = NULL;
5890 chan->sdu_last_frag = NULL;
5891 chan->sdu_len = 0;
5892 }
5893 break;
5894 }
5895
5896 if (err) {
5897 kfree_skb(skb);
5898 kfree_skb(chan->sdu);
5899 chan->sdu = NULL;
5900 chan->sdu_last_frag = NULL;
5901 chan->sdu_len = 0;
5902 }
5903
5904 return err;
5905 }
5906
5907 static int l2cap_resegment(struct l2cap_chan *chan)
5908 {
5909 /* Placeholder */
5910 return 0;
5911 }
5912
5913 void l2cap_chan_busy(struct l2cap_chan *chan, int busy)
5914 {
5915 u8 event;
5916
5917 if (chan->mode != L2CAP_MODE_ERTM)
5918 return;
5919
5920 event = busy ? L2CAP_EV_LOCAL_BUSY_DETECTED : L2CAP_EV_LOCAL_BUSY_CLEAR;
5921 l2cap_tx(chan, NULL, NULL, event);
5922 }
5923
5924 static int l2cap_rx_queued_iframes(struct l2cap_chan *chan)
5925 {
5926 int err = 0;
5927 /* Pass sequential frames to l2cap_reassemble_sdu()
5928 * until a gap is encountered.
5929 */
5930
5931 BT_DBG("chan %p", chan);
5932
5933 while (!test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
5934 struct sk_buff *skb;
5935 BT_DBG("Searching for skb with txseq %d (queue len %d)",
5936 chan->buffer_seq, skb_queue_len(&chan->srej_q));
5937
5938 skb = l2cap_ertm_seq_in_queue(&chan->srej_q, chan->buffer_seq);
5939
5940 if (!skb)
5941 break;
5942
5943 skb_unlink(skb, &chan->srej_q);
5944 chan->buffer_seq = __next_seq(chan, chan->buffer_seq);
5945 err = l2cap_reassemble_sdu(chan, skb, &bt_cb(skb)->l2cap);
5946 if (err)
5947 break;
5948 }
5949
5950 if (skb_queue_empty(&chan->srej_q)) {
5951 chan->rx_state = L2CAP_RX_STATE_RECV;
5952 l2cap_send_ack(chan);
5953 }
5954
5955 return err;
5956 }
5957
5958 static void l2cap_handle_srej(struct l2cap_chan *chan,
5959 struct l2cap_ctrl *control)
5960 {
5961 struct sk_buff *skb;
5962
5963 BT_DBG("chan %p, control %p", chan, control);
5964
5965 if (control->reqseq == chan->next_tx_seq) {
5966 BT_DBG("Invalid reqseq %d, disconnecting", control->reqseq);
5967 l2cap_send_disconn_req(chan, ECONNRESET);
5968 return;
5969 }
5970
5971 skb = l2cap_ertm_seq_in_queue(&chan->tx_q, control->reqseq);
5972
5973 if (skb == NULL) {
5974 BT_DBG("Seq %d not available for retransmission",
5975 control->reqseq);
5976 return;
5977 }
5978
5979 if (chan->max_tx != 0 && bt_cb(skb)->l2cap.retries >= chan->max_tx) {
5980 BT_DBG("Retry limit exceeded (%d)", chan->max_tx);
5981 l2cap_send_disconn_req(chan, ECONNRESET);
5982 return;
5983 }
5984
5985 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
5986
5987 if (control->poll) {
5988 l2cap_pass_to_tx(chan, control);
5989
5990 set_bit(CONN_SEND_FBIT, &chan->conn_state);
5991 l2cap_retransmit(chan, control);
5992 l2cap_ertm_send(chan);
5993
5994 if (chan->tx_state == L2CAP_TX_STATE_WAIT_F) {
5995 set_bit(CONN_SREJ_ACT, &chan->conn_state);
5996 chan->srej_save_reqseq = control->reqseq;
5997 }
5998 } else {
5999 l2cap_pass_to_tx_fbit(chan, control);
6000
6001 if (control->final) {
6002 if (chan->srej_save_reqseq != control->reqseq ||
6003 !test_and_clear_bit(CONN_SREJ_ACT,
6004 &chan->conn_state))
6005 l2cap_retransmit(chan, control);
6006 } else {
6007 l2cap_retransmit(chan, control);
6008 if (chan->tx_state == L2CAP_TX_STATE_WAIT_F) {
6009 set_bit(CONN_SREJ_ACT, &chan->conn_state);
6010 chan->srej_save_reqseq = control->reqseq;
6011 }
6012 }
6013 }
6014 }
6015
6016 static void l2cap_handle_rej(struct l2cap_chan *chan,
6017 struct l2cap_ctrl *control)
6018 {
6019 struct sk_buff *skb;
6020
6021 BT_DBG("chan %p, control %p", chan, control);
6022
6023 if (control->reqseq == chan->next_tx_seq) {
6024 BT_DBG("Invalid reqseq %d, disconnecting", control->reqseq);
6025 l2cap_send_disconn_req(chan, ECONNRESET);
6026 return;
6027 }
6028
6029 skb = l2cap_ertm_seq_in_queue(&chan->tx_q, control->reqseq);
6030
6031 if (chan->max_tx && skb &&
6032 bt_cb(skb)->l2cap.retries >= chan->max_tx) {
6033 BT_DBG("Retry limit exceeded (%d)", chan->max_tx);
6034 l2cap_send_disconn_req(chan, ECONNRESET);
6035 return;
6036 }
6037
6038 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6039
6040 l2cap_pass_to_tx(chan, control);
6041
6042 if (control->final) {
6043 if (!test_and_clear_bit(CONN_REJ_ACT, &chan->conn_state))
6044 l2cap_retransmit_all(chan, control);
6045 } else {
6046 l2cap_retransmit_all(chan, control);
6047 l2cap_ertm_send(chan);
6048 if (chan->tx_state == L2CAP_TX_STATE_WAIT_F)
6049 set_bit(CONN_REJ_ACT, &chan->conn_state);
6050 }
6051 }
6052
6053 static u8 l2cap_classify_txseq(struct l2cap_chan *chan, u16 txseq)
6054 {
6055 BT_DBG("chan %p, txseq %d", chan, txseq);
6056
6057 BT_DBG("last_acked_seq %d, expected_tx_seq %d", chan->last_acked_seq,
6058 chan->expected_tx_seq);
6059
6060 if (chan->rx_state == L2CAP_RX_STATE_SREJ_SENT) {
6061 if (__seq_offset(chan, txseq, chan->last_acked_seq) >=
6062 chan->tx_win) {
6063 /* See notes below regarding "double poll" and
6064 * invalid packets.
6065 */
6066 if (chan->tx_win <= ((chan->tx_win_max + 1) >> 1)) {
6067 BT_DBG("Invalid/Ignore - after SREJ");
6068 return L2CAP_TXSEQ_INVALID_IGNORE;
6069 } else {
6070 BT_DBG("Invalid - in window after SREJ sent");
6071 return L2CAP_TXSEQ_INVALID;
6072 }
6073 }
6074
6075 if (chan->srej_list.head == txseq) {
6076 BT_DBG("Expected SREJ");
6077 return L2CAP_TXSEQ_EXPECTED_SREJ;
6078 }
6079
6080 if (l2cap_ertm_seq_in_queue(&chan->srej_q, txseq)) {
6081 BT_DBG("Duplicate SREJ - txseq already stored");
6082 return L2CAP_TXSEQ_DUPLICATE_SREJ;
6083 }
6084
6085 if (l2cap_seq_list_contains(&chan->srej_list, txseq)) {
6086 BT_DBG("Unexpected SREJ - not requested");
6087 return L2CAP_TXSEQ_UNEXPECTED_SREJ;
6088 }
6089 }
6090
6091 if (chan->expected_tx_seq == txseq) {
6092 if (__seq_offset(chan, txseq, chan->last_acked_seq) >=
6093 chan->tx_win) {
6094 BT_DBG("Invalid - txseq outside tx window");
6095 return L2CAP_TXSEQ_INVALID;
6096 } else {
6097 BT_DBG("Expected");
6098 return L2CAP_TXSEQ_EXPECTED;
6099 }
6100 }
6101
6102 if (__seq_offset(chan, txseq, chan->last_acked_seq) <
6103 __seq_offset(chan, chan->expected_tx_seq, chan->last_acked_seq)) {
6104 BT_DBG("Duplicate - expected_tx_seq later than txseq");
6105 return L2CAP_TXSEQ_DUPLICATE;
6106 }
6107
6108 if (__seq_offset(chan, txseq, chan->last_acked_seq) >= chan->tx_win) {
6109 /* A source of invalid packets is a "double poll" condition,
6110 * where delays cause us to send multiple poll packets. If
6111 * the remote stack receives and processes both polls,
6112 * sequence numbers can wrap around in such a way that a
6113 * resent frame has a sequence number that looks like new data
6114 * with a sequence gap. This would trigger an erroneous SREJ
6115 * request.
6116 *
6117 * Fortunately, this is impossible with a tx window that's
6118 * less than half of the maximum sequence number, which allows
6119 * invalid frames to be safely ignored.
6120 *
6121 * With tx window sizes greater than half of the tx window
6122 * maximum, the frame is invalid and cannot be ignored. This
6123 * causes a disconnect.
6124 */
6125
6126 if (chan->tx_win <= ((chan->tx_win_max + 1) >> 1)) {
6127 BT_DBG("Invalid/Ignore - txseq outside tx window");
6128 return L2CAP_TXSEQ_INVALID_IGNORE;
6129 } else {
6130 BT_DBG("Invalid - txseq outside tx window");
6131 return L2CAP_TXSEQ_INVALID;
6132 }
6133 } else {
6134 BT_DBG("Unexpected - txseq indicates missing frames");
6135 return L2CAP_TXSEQ_UNEXPECTED;
6136 }
6137 }
6138
6139 static int l2cap_rx_state_recv(struct l2cap_chan *chan,
6140 struct l2cap_ctrl *control,
6141 struct sk_buff *skb, u8 event)
6142 {
6143 int err = 0;
6144 bool skb_in_use = false;
6145
6146 BT_DBG("chan %p, control %p, skb %p, event %d", chan, control, skb,
6147 event);
6148
6149 switch (event) {
6150 case L2CAP_EV_RECV_IFRAME:
6151 switch (l2cap_classify_txseq(chan, control->txseq)) {
6152 case L2CAP_TXSEQ_EXPECTED:
6153 l2cap_pass_to_tx(chan, control);
6154
6155 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
6156 BT_DBG("Busy, discarding expected seq %d",
6157 control->txseq);
6158 break;
6159 }
6160
6161 chan->expected_tx_seq = __next_seq(chan,
6162 control->txseq);
6163
6164 chan->buffer_seq = chan->expected_tx_seq;
6165 skb_in_use = true;
6166
6167 err = l2cap_reassemble_sdu(chan, skb, control);
6168 if (err)
6169 break;
6170
6171 if (control->final) {
6172 if (!test_and_clear_bit(CONN_REJ_ACT,
6173 &chan->conn_state)) {
6174 control->final = 0;
6175 l2cap_retransmit_all(chan, control);
6176 l2cap_ertm_send(chan);
6177 }
6178 }
6179
6180 if (!test_bit(CONN_LOCAL_BUSY, &chan->conn_state))
6181 l2cap_send_ack(chan);
6182 break;
6183 case L2CAP_TXSEQ_UNEXPECTED:
6184 l2cap_pass_to_tx(chan, control);
6185
6186 /* Can't issue SREJ frames in the local busy state.
6187 * Drop this frame, it will be seen as missing
6188 * when local busy is exited.
6189 */
6190 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
6191 BT_DBG("Busy, discarding unexpected seq %d",
6192 control->txseq);
6193 break;
6194 }
6195
6196 /* There was a gap in the sequence, so an SREJ
6197 * must be sent for each missing frame. The
6198 * current frame is stored for later use.
6199 */
6200 skb_queue_tail(&chan->srej_q, skb);
6201 skb_in_use = true;
6202 BT_DBG("Queued %p (queue len %d)", skb,
6203 skb_queue_len(&chan->srej_q));
6204
6205 clear_bit(CONN_SREJ_ACT, &chan->conn_state);
6206 l2cap_seq_list_clear(&chan->srej_list);
6207 l2cap_send_srej(chan, control->txseq);
6208
6209 chan->rx_state = L2CAP_RX_STATE_SREJ_SENT;
6210 break;
6211 case L2CAP_TXSEQ_DUPLICATE:
6212 l2cap_pass_to_tx(chan, control);
6213 break;
6214 case L2CAP_TXSEQ_INVALID_IGNORE:
6215 break;
6216 case L2CAP_TXSEQ_INVALID:
6217 default:
6218 l2cap_send_disconn_req(chan, ECONNRESET);
6219 break;
6220 }
6221 break;
6222 case L2CAP_EV_RECV_RR:
6223 l2cap_pass_to_tx(chan, control);
6224 if (control->final) {
6225 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6226
6227 if (!test_and_clear_bit(CONN_REJ_ACT, &chan->conn_state) &&
6228 !__chan_is_moving(chan)) {
6229 control->final = 0;
6230 l2cap_retransmit_all(chan, control);
6231 }
6232
6233 l2cap_ertm_send(chan);
6234 } else if (control->poll) {
6235 l2cap_send_i_or_rr_or_rnr(chan);
6236 } else {
6237 if (test_and_clear_bit(CONN_REMOTE_BUSY,
6238 &chan->conn_state) &&
6239 chan->unacked_frames)
6240 __set_retrans_timer(chan);
6241
6242 l2cap_ertm_send(chan);
6243 }
6244 break;
6245 case L2CAP_EV_RECV_RNR:
6246 set_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6247 l2cap_pass_to_tx(chan, control);
6248 if (control && control->poll) {
6249 set_bit(CONN_SEND_FBIT, &chan->conn_state);
6250 l2cap_send_rr_or_rnr(chan, 0);
6251 }
6252 __clear_retrans_timer(chan);
6253 l2cap_seq_list_clear(&chan->retrans_list);
6254 break;
6255 case L2CAP_EV_RECV_REJ:
6256 l2cap_handle_rej(chan, control);
6257 break;
6258 case L2CAP_EV_RECV_SREJ:
6259 l2cap_handle_srej(chan, control);
6260 break;
6261 default:
6262 break;
6263 }
6264
6265 if (skb && !skb_in_use) {
6266 BT_DBG("Freeing %p", skb);
6267 kfree_skb(skb);
6268 }
6269
6270 return err;
6271 }
6272
6273 static int l2cap_rx_state_srej_sent(struct l2cap_chan *chan,
6274 struct l2cap_ctrl *control,
6275 struct sk_buff *skb, u8 event)
6276 {
6277 int err = 0;
6278 u16 txseq = control->txseq;
6279 bool skb_in_use = false;
6280
6281 BT_DBG("chan %p, control %p, skb %p, event %d", chan, control, skb,
6282 event);
6283
6284 switch (event) {
6285 case L2CAP_EV_RECV_IFRAME:
6286 switch (l2cap_classify_txseq(chan, txseq)) {
6287 case L2CAP_TXSEQ_EXPECTED:
6288 /* Keep frame for reassembly later */
6289 l2cap_pass_to_tx(chan, control);
6290 skb_queue_tail(&chan->srej_q, skb);
6291 skb_in_use = true;
6292 BT_DBG("Queued %p (queue len %d)", skb,
6293 skb_queue_len(&chan->srej_q));
6294
6295 chan->expected_tx_seq = __next_seq(chan, txseq);
6296 break;
6297 case L2CAP_TXSEQ_EXPECTED_SREJ:
6298 l2cap_seq_list_pop(&chan->srej_list);
6299
6300 l2cap_pass_to_tx(chan, control);
6301 skb_queue_tail(&chan->srej_q, skb);
6302 skb_in_use = true;
6303 BT_DBG("Queued %p (queue len %d)", skb,
6304 skb_queue_len(&chan->srej_q));
6305
6306 err = l2cap_rx_queued_iframes(chan);
6307 if (err)
6308 break;
6309
6310 break;
6311 case L2CAP_TXSEQ_UNEXPECTED:
6312 /* Got a frame that can't be reassembled yet.
6313 * Save it for later, and send SREJs to cover
6314 * the missing frames.
6315 */
6316 skb_queue_tail(&chan->srej_q, skb);
6317 skb_in_use = true;
6318 BT_DBG("Queued %p (queue len %d)", skb,
6319 skb_queue_len(&chan->srej_q));
6320
6321 l2cap_pass_to_tx(chan, control);
6322 l2cap_send_srej(chan, control->txseq);
6323 break;
6324 case L2CAP_TXSEQ_UNEXPECTED_SREJ:
6325 /* This frame was requested with an SREJ, but
6326 * some expected retransmitted frames are
6327 * missing. Request retransmission of missing
6328 * SREJ'd frames.
6329 */
6330 skb_queue_tail(&chan->srej_q, skb);
6331 skb_in_use = true;
6332 BT_DBG("Queued %p (queue len %d)", skb,
6333 skb_queue_len(&chan->srej_q));
6334
6335 l2cap_pass_to_tx(chan, control);
6336 l2cap_send_srej_list(chan, control->txseq);
6337 break;
6338 case L2CAP_TXSEQ_DUPLICATE_SREJ:
6339 /* We've already queued this frame. Drop this copy. */
6340 l2cap_pass_to_tx(chan, control);
6341 break;
6342 case L2CAP_TXSEQ_DUPLICATE:
6343 /* Expecting a later sequence number, so this frame
6344 * was already received. Ignore it completely.
6345 */
6346 break;
6347 case L2CAP_TXSEQ_INVALID_IGNORE:
6348 break;
6349 case L2CAP_TXSEQ_INVALID:
6350 default:
6351 l2cap_send_disconn_req(chan, ECONNRESET);
6352 break;
6353 }
6354 break;
6355 case L2CAP_EV_RECV_RR:
6356 l2cap_pass_to_tx(chan, control);
6357 if (control->final) {
6358 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6359
6360 if (!test_and_clear_bit(CONN_REJ_ACT,
6361 &chan->conn_state)) {
6362 control->final = 0;
6363 l2cap_retransmit_all(chan, control);
6364 }
6365
6366 l2cap_ertm_send(chan);
6367 } else if (control->poll) {
6368 if (test_and_clear_bit(CONN_REMOTE_BUSY,
6369 &chan->conn_state) &&
6370 chan->unacked_frames) {
6371 __set_retrans_timer(chan);
6372 }
6373
6374 set_bit(CONN_SEND_FBIT, &chan->conn_state);
6375 l2cap_send_srej_tail(chan);
6376 } else {
6377 if (test_and_clear_bit(CONN_REMOTE_BUSY,
6378 &chan->conn_state) &&
6379 chan->unacked_frames)
6380 __set_retrans_timer(chan);
6381
6382 l2cap_send_ack(chan);
6383 }
6384 break;
6385 case L2CAP_EV_RECV_RNR:
6386 set_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6387 l2cap_pass_to_tx(chan, control);
6388 if (control->poll) {
6389 l2cap_send_srej_tail(chan);
6390 } else {
6391 struct l2cap_ctrl rr_control;
6392 memset(&rr_control, 0, sizeof(rr_control));
6393 rr_control.sframe = 1;
6394 rr_control.super = L2CAP_SUPER_RR;
6395 rr_control.reqseq = chan->buffer_seq;
6396 l2cap_send_sframe(chan, &rr_control);
6397 }
6398
6399 break;
6400 case L2CAP_EV_RECV_REJ:
6401 l2cap_handle_rej(chan, control);
6402 break;
6403 case L2CAP_EV_RECV_SREJ:
6404 l2cap_handle_srej(chan, control);
6405 break;
6406 }
6407
6408 if (skb && !skb_in_use) {
6409 BT_DBG("Freeing %p", skb);
6410 kfree_skb(skb);
6411 }
6412
6413 return err;
6414 }
6415
6416 static int l2cap_finish_move(struct l2cap_chan *chan)
6417 {
6418 BT_DBG("chan %p", chan);
6419
6420 chan->rx_state = L2CAP_RX_STATE_RECV;
6421
6422 if (chan->hs_hcon)
6423 chan->conn->mtu = chan->hs_hcon->hdev->block_mtu;
6424 else
6425 chan->conn->mtu = chan->conn->hcon->hdev->acl_mtu;
6426
6427 return l2cap_resegment(chan);
6428 }
6429
6430 static int l2cap_rx_state_wait_p(struct l2cap_chan *chan,
6431 struct l2cap_ctrl *control,
6432 struct sk_buff *skb, u8 event)
6433 {
6434 int err;
6435
6436 BT_DBG("chan %p, control %p, skb %p, event %d", chan, control, skb,
6437 event);
6438
6439 if (!control->poll)
6440 return -EPROTO;
6441
6442 l2cap_process_reqseq(chan, control->reqseq);
6443
6444 if (!skb_queue_empty(&chan->tx_q))
6445 chan->tx_send_head = skb_peek(&chan->tx_q);
6446 else
6447 chan->tx_send_head = NULL;
6448
6449 /* Rewind next_tx_seq to the point expected
6450 * by the receiver.
6451 */
6452 chan->next_tx_seq = control->reqseq;
6453 chan->unacked_frames = 0;
6454
6455 err = l2cap_finish_move(chan);
6456 if (err)
6457 return err;
6458
6459 set_bit(CONN_SEND_FBIT, &chan->conn_state);
6460 l2cap_send_i_or_rr_or_rnr(chan);
6461
6462 if (event == L2CAP_EV_RECV_IFRAME)
6463 return -EPROTO;
6464
6465 return l2cap_rx_state_recv(chan, control, NULL, event);
6466 }
6467
6468 static int l2cap_rx_state_wait_f(struct l2cap_chan *chan,
6469 struct l2cap_ctrl *control,
6470 struct sk_buff *skb, u8 event)
6471 {
6472 int err;
6473
6474 if (!control->final)
6475 return -EPROTO;
6476
6477 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6478
6479 chan->rx_state = L2CAP_RX_STATE_RECV;
6480 l2cap_process_reqseq(chan, control->reqseq);
6481
6482 if (!skb_queue_empty(&chan->tx_q))
6483 chan->tx_send_head = skb_peek(&chan->tx_q);
6484 else
6485 chan->tx_send_head = NULL;
6486
6487 /* Rewind next_tx_seq to the point expected
6488 * by the receiver.
6489 */
6490 chan->next_tx_seq = control->reqseq;
6491 chan->unacked_frames = 0;
6492
6493 if (chan->hs_hcon)
6494 chan->conn->mtu = chan->hs_hcon->hdev->block_mtu;
6495 else
6496 chan->conn->mtu = chan->conn->hcon->hdev->acl_mtu;
6497
6498 err = l2cap_resegment(chan);
6499
6500 if (!err)
6501 err = l2cap_rx_state_recv(chan, control, skb, event);
6502
6503 return err;
6504 }
6505
6506 static bool __valid_reqseq(struct l2cap_chan *chan, u16 reqseq)
6507 {
6508 /* Make sure reqseq is for a packet that has been sent but not acked */
6509 u16 unacked;
6510
6511 unacked = __seq_offset(chan, chan->next_tx_seq, chan->expected_ack_seq);
6512 return __seq_offset(chan, chan->next_tx_seq, reqseq) <= unacked;
6513 }
6514
6515 static int l2cap_rx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
6516 struct sk_buff *skb, u8 event)
6517 {
6518 int err = 0;
6519
6520 BT_DBG("chan %p, control %p, skb %p, event %d, state %d", chan,
6521 control, skb, event, chan->rx_state);
6522
6523 if (__valid_reqseq(chan, control->reqseq)) {
6524 switch (chan->rx_state) {
6525 case L2CAP_RX_STATE_RECV:
6526 err = l2cap_rx_state_recv(chan, control, skb, event);
6527 break;
6528 case L2CAP_RX_STATE_SREJ_SENT:
6529 err = l2cap_rx_state_srej_sent(chan, control, skb,
6530 event);
6531 break;
6532 case L2CAP_RX_STATE_WAIT_P:
6533 err = l2cap_rx_state_wait_p(chan, control, skb, event);
6534 break;
6535 case L2CAP_RX_STATE_WAIT_F:
6536 err = l2cap_rx_state_wait_f(chan, control, skb, event);
6537 break;
6538 default:
6539 /* shut it down */
6540 break;
6541 }
6542 } else {
6543 BT_DBG("Invalid reqseq %d (next_tx_seq %d, expected_ack_seq %d",
6544 control->reqseq, chan->next_tx_seq,
6545 chan->expected_ack_seq);
6546 l2cap_send_disconn_req(chan, ECONNRESET);
6547 }
6548
6549 return err;
6550 }
6551
6552 static int l2cap_stream_rx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
6553 struct sk_buff *skb)
6554 {
6555 BT_DBG("chan %p, control %p, skb %p, state %d", chan, control, skb,
6556 chan->rx_state);
6557
6558 if (l2cap_classify_txseq(chan, control->txseq) ==
6559 L2CAP_TXSEQ_EXPECTED) {
6560 l2cap_pass_to_tx(chan, control);
6561
6562 BT_DBG("buffer_seq %d->%d", chan->buffer_seq,
6563 __next_seq(chan, chan->buffer_seq));
6564
6565 chan->buffer_seq = __next_seq(chan, chan->buffer_seq);
6566
6567 l2cap_reassemble_sdu(chan, skb, control);
6568 } else {
6569 if (chan->sdu) {
6570 kfree_skb(chan->sdu);
6571 chan->sdu = NULL;
6572 }
6573 chan->sdu_last_frag = NULL;
6574 chan->sdu_len = 0;
6575
6576 if (skb) {
6577 BT_DBG("Freeing %p", skb);
6578 kfree_skb(skb);
6579 }
6580 }
6581
6582 chan->last_acked_seq = control->txseq;
6583 chan->expected_tx_seq = __next_seq(chan, control->txseq);
6584
6585 return 0;
6586 }
6587
6588 static int l2cap_data_rcv(struct l2cap_chan *chan, struct sk_buff *skb)
6589 {
6590 struct l2cap_ctrl *control = &bt_cb(skb)->l2cap;
6591 u16 len;
6592 u8 event;
6593
6594 __unpack_control(chan, skb);
6595
6596 len = skb->len;
6597
6598 /*
6599 * We can just drop the corrupted I-frame here.
6600 * Receiver will miss it and start proper recovery
6601 * procedures and ask for retransmission.
6602 */
6603 if (l2cap_check_fcs(chan, skb))
6604 goto drop;
6605
6606 if (!control->sframe && control->sar == L2CAP_SAR_START)
6607 len -= L2CAP_SDULEN_SIZE;
6608
6609 if (chan->fcs == L2CAP_FCS_CRC16)
6610 len -= L2CAP_FCS_SIZE;
6611
6612 if (len > chan->mps) {
6613 l2cap_send_disconn_req(chan, ECONNRESET);
6614 goto drop;
6615 }
6616
6617 if ((chan->mode == L2CAP_MODE_ERTM ||
6618 chan->mode == L2CAP_MODE_STREAMING) && sk_filter(chan->data, skb))
6619 goto drop;
6620
6621 if (!control->sframe) {
6622 int err;
6623
6624 BT_DBG("iframe sar %d, reqseq %d, final %d, txseq %d",
6625 control->sar, control->reqseq, control->final,
6626 control->txseq);
6627
6628 /* Validate F-bit - F=0 always valid, F=1 only
6629 * valid in TX WAIT_F
6630 */
6631 if (control->final && chan->tx_state != L2CAP_TX_STATE_WAIT_F)
6632 goto drop;
6633
6634 if (chan->mode != L2CAP_MODE_STREAMING) {
6635 event = L2CAP_EV_RECV_IFRAME;
6636 err = l2cap_rx(chan, control, skb, event);
6637 } else {
6638 err = l2cap_stream_rx(chan, control, skb);
6639 }
6640
6641 if (err)
6642 l2cap_send_disconn_req(chan, ECONNRESET);
6643 } else {
6644 const u8 rx_func_to_event[4] = {
6645 L2CAP_EV_RECV_RR, L2CAP_EV_RECV_REJ,
6646 L2CAP_EV_RECV_RNR, L2CAP_EV_RECV_SREJ
6647 };
6648
6649 /* Only I-frames are expected in streaming mode */
6650 if (chan->mode == L2CAP_MODE_STREAMING)
6651 goto drop;
6652
6653 BT_DBG("sframe reqseq %d, final %d, poll %d, super %d",
6654 control->reqseq, control->final, control->poll,
6655 control->super);
6656
6657 if (len != 0) {
6658 BT_ERR("Trailing bytes: %d in sframe", len);
6659 l2cap_send_disconn_req(chan, ECONNRESET);
6660 goto drop;
6661 }
6662
6663 /* Validate F and P bits */
6664 if (control->final && (control->poll ||
6665 chan->tx_state != L2CAP_TX_STATE_WAIT_F))
6666 goto drop;
6667
6668 event = rx_func_to_event[control->super];
6669 if (l2cap_rx(chan, control, skb, event))
6670 l2cap_send_disconn_req(chan, ECONNRESET);
6671 }
6672
6673 return 0;
6674
6675 drop:
6676 kfree_skb(skb);
6677 return 0;
6678 }
6679
6680 static void l2cap_chan_le_send_credits(struct l2cap_chan *chan)
6681 {
6682 struct l2cap_conn *conn = chan->conn;
6683 struct l2cap_le_credits pkt;
6684 u16 return_credits;
6685
6686 /* We return more credits to the sender only after the amount of
6687 * credits falls below half of the initial amount.
6688 */
6689 if (chan->rx_credits >= (le_max_credits + 1) / 2)
6690 return;
6691
6692 return_credits = le_max_credits - chan->rx_credits;
6693
6694 BT_DBG("chan %p returning %u credits to sender", chan, return_credits);
6695
6696 chan->rx_credits += return_credits;
6697
6698 pkt.cid = cpu_to_le16(chan->scid);
6699 pkt.credits = cpu_to_le16(return_credits);
6700
6701 chan->ident = l2cap_get_ident(conn);
6702
6703 l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CREDITS, sizeof(pkt), &pkt);
6704 }
6705
6706 static int l2cap_le_data_rcv(struct l2cap_chan *chan, struct sk_buff *skb)
6707 {
6708 int err;
6709
6710 if (!chan->rx_credits) {
6711 BT_ERR("No credits to receive LE L2CAP data");
6712 l2cap_send_disconn_req(chan, ECONNRESET);
6713 return -ENOBUFS;
6714 }
6715
6716 if (chan->imtu < skb->len) {
6717 BT_ERR("Too big LE L2CAP PDU");
6718 return -ENOBUFS;
6719 }
6720
6721 chan->rx_credits--;
6722 BT_DBG("rx_credits %u -> %u", chan->rx_credits + 1, chan->rx_credits);
6723
6724 l2cap_chan_le_send_credits(chan);
6725
6726 err = 0;
6727
6728 if (!chan->sdu) {
6729 u16 sdu_len;
6730
6731 sdu_len = get_unaligned_le16(skb->data);
6732 skb_pull(skb, L2CAP_SDULEN_SIZE);
6733
6734 BT_DBG("Start of new SDU. sdu_len %u skb->len %u imtu %u",
6735 sdu_len, skb->len, chan->imtu);
6736
6737 if (sdu_len > chan->imtu) {
6738 BT_ERR("Too big LE L2CAP SDU length received");
6739 err = -EMSGSIZE;
6740 goto failed;
6741 }
6742
6743 if (skb->len > sdu_len) {
6744 BT_ERR("Too much LE L2CAP data received");
6745 err = -EINVAL;
6746 goto failed;
6747 }
6748
6749 if (skb->len == sdu_len)
6750 return chan->ops->recv(chan, skb);
6751
6752 chan->sdu = skb;
6753 chan->sdu_len = sdu_len;
6754 chan->sdu_last_frag = skb;
6755
6756 return 0;
6757 }
6758
6759 BT_DBG("SDU fragment. chan->sdu->len %u skb->len %u chan->sdu_len %u",
6760 chan->sdu->len, skb->len, chan->sdu_len);
6761
6762 if (chan->sdu->len + skb->len > chan->sdu_len) {
6763 BT_ERR("Too much LE L2CAP data received");
6764 err = -EINVAL;
6765 goto failed;
6766 }
6767
6768 append_skb_frag(chan->sdu, skb, &chan->sdu_last_frag);
6769 skb = NULL;
6770
6771 if (chan->sdu->len == chan->sdu_len) {
6772 err = chan->ops->recv(chan, chan->sdu);
6773 if (!err) {
6774 chan->sdu = NULL;
6775 chan->sdu_last_frag = NULL;
6776 chan->sdu_len = 0;
6777 }
6778 }
6779
6780 failed:
6781 if (err) {
6782 kfree_skb(skb);
6783 kfree_skb(chan->sdu);
6784 chan->sdu = NULL;
6785 chan->sdu_last_frag = NULL;
6786 chan->sdu_len = 0;
6787 }
6788
6789 /* We can't return an error here since we took care of the skb
6790 * freeing internally. An error return would cause the caller to
6791 * do a double-free of the skb.
6792 */
6793 return 0;
6794 }
6795
6796 static void l2cap_data_channel(struct l2cap_conn *conn, u16 cid,
6797 struct sk_buff *skb)
6798 {
6799 struct l2cap_chan *chan;
6800
6801 chan = l2cap_get_chan_by_scid(conn, cid);
6802 if (!chan) {
6803 if (cid == L2CAP_CID_A2MP) {
6804 chan = a2mp_channel_create(conn, skb);
6805 if (!chan) {
6806 kfree_skb(skb);
6807 return;
6808 }
6809
6810 l2cap_chan_lock(chan);
6811 } else {
6812 BT_DBG("unknown cid 0x%4.4x", cid);
6813 /* Drop packet and return */
6814 kfree_skb(skb);
6815 return;
6816 }
6817 }
6818
6819 BT_DBG("chan %p, len %d", chan, skb->len);
6820
6821 /* If we receive data on a fixed channel before the info req/rsp
6822 * procdure is done simply assume that the channel is supported
6823 * and mark it as ready.
6824 */
6825 if (chan->chan_type == L2CAP_CHAN_FIXED)
6826 l2cap_chan_ready(chan);
6827
6828 if (chan->state != BT_CONNECTED)
6829 goto drop;
6830
6831 switch (chan->mode) {
6832 case L2CAP_MODE_LE_FLOWCTL:
6833 if (l2cap_le_data_rcv(chan, skb) < 0)
6834 goto drop;
6835
6836 goto done;
6837
6838 case L2CAP_MODE_BASIC:
6839 /* If socket recv buffers overflows we drop data here
6840 * which is *bad* because L2CAP has to be reliable.
6841 * But we don't have any other choice. L2CAP doesn't
6842 * provide flow control mechanism. */
6843
6844 if (chan->imtu < skb->len) {
6845 BT_ERR("Dropping L2CAP data: receive buffer overflow");
6846 goto drop;
6847 }
6848
6849 if (!chan->ops->recv(chan, skb))
6850 goto done;
6851 break;
6852
6853 case L2CAP_MODE_ERTM:
6854 case L2CAP_MODE_STREAMING:
6855 l2cap_data_rcv(chan, skb);
6856 goto done;
6857
6858 default:
6859 BT_DBG("chan %p: bad mode 0x%2.2x", chan, chan->mode);
6860 break;
6861 }
6862
6863 drop:
6864 kfree_skb(skb);
6865
6866 done:
6867 l2cap_chan_unlock(chan);
6868 }
6869
6870 static void l2cap_conless_channel(struct l2cap_conn *conn, __le16 psm,
6871 struct sk_buff *skb)
6872 {
6873 struct hci_conn *hcon = conn->hcon;
6874 struct l2cap_chan *chan;
6875
6876 if (hcon->type != ACL_LINK)
6877 goto free_skb;
6878
6879 chan = l2cap_global_chan_by_psm(0, psm, &hcon->src, &hcon->dst,
6880 ACL_LINK);
6881 if (!chan)
6882 goto free_skb;
6883
6884 BT_DBG("chan %p, len %d", chan, skb->len);
6885
6886 if (chan->state != BT_BOUND && chan->state != BT_CONNECTED)
6887 goto drop;
6888
6889 if (chan->imtu < skb->len)
6890 goto drop;
6891
6892 /* Store remote BD_ADDR and PSM for msg_name */
6893 bacpy(&bt_cb(skb)->l2cap.bdaddr, &hcon->dst);
6894 bt_cb(skb)->l2cap.psm = psm;
6895
6896 if (!chan->ops->recv(chan, skb)) {
6897 l2cap_chan_put(chan);
6898 return;
6899 }
6900
6901 drop:
6902 l2cap_chan_put(chan);
6903 free_skb:
6904 kfree_skb(skb);
6905 }
6906
6907 static void l2cap_recv_frame(struct l2cap_conn *conn, struct sk_buff *skb)
6908 {
6909 struct l2cap_hdr *lh = (void *) skb->data;
6910 struct hci_conn *hcon = conn->hcon;
6911 u16 cid, len;
6912 __le16 psm;
6913
6914 if (hcon->state != BT_CONNECTED) {
6915 BT_DBG("queueing pending rx skb");
6916 skb_queue_tail(&conn->pending_rx, skb);
6917 return;
6918 }
6919
6920 skb_pull(skb, L2CAP_HDR_SIZE);
6921 cid = __le16_to_cpu(lh->cid);
6922 len = __le16_to_cpu(lh->len);
6923
6924 if (len != skb->len) {
6925 kfree_skb(skb);
6926 return;
6927 }
6928
6929 /* Since we can't actively block incoming LE connections we must
6930 * at least ensure that we ignore incoming data from them.
6931 */
6932 if (hcon->type == LE_LINK &&
6933 hci_bdaddr_list_lookup(&hcon->hdev->blacklist, &hcon->dst,
6934 bdaddr_dst_type(hcon))) {
6935 kfree_skb(skb);
6936 return;
6937 }
6938
6939 BT_DBG("len %d, cid 0x%4.4x", len, cid);
6940
6941 switch (cid) {
6942 case L2CAP_CID_SIGNALING:
6943 l2cap_sig_channel(conn, skb);
6944 break;
6945
6946 case L2CAP_CID_CONN_LESS:
6947 psm = get_unaligned((__le16 *) skb->data);
6948 skb_pull(skb, L2CAP_PSMLEN_SIZE);
6949 l2cap_conless_channel(conn, psm, skb);
6950 break;
6951
6952 case L2CAP_CID_LE_SIGNALING:
6953 l2cap_le_sig_channel(conn, skb);
6954 break;
6955
6956 default:
6957 l2cap_data_channel(conn, cid, skb);
6958 break;
6959 }
6960 }
6961
6962 static void process_pending_rx(struct work_struct *work)
6963 {
6964 struct l2cap_conn *conn = container_of(work, struct l2cap_conn,
6965 pending_rx_work);
6966 struct sk_buff *skb;
6967
6968 BT_DBG("");
6969
6970 while ((skb = skb_dequeue(&conn->pending_rx)))
6971 l2cap_recv_frame(conn, skb);
6972 }
6973
6974 static struct l2cap_conn *l2cap_conn_add(struct hci_conn *hcon)
6975 {
6976 struct l2cap_conn *conn = hcon->l2cap_data;
6977 struct hci_chan *hchan;
6978
6979 if (conn)
6980 return conn;
6981
6982 hchan = hci_chan_create(hcon);
6983 if (!hchan)
6984 return NULL;
6985
6986 conn = kzalloc(sizeof(*conn), GFP_KERNEL);
6987 if (!conn) {
6988 hci_chan_del(hchan);
6989 return NULL;
6990 }
6991
6992 kref_init(&conn->ref);
6993 hcon->l2cap_data = conn;
6994 conn->hcon = hci_conn_get(hcon);
6995 conn->hchan = hchan;
6996
6997 BT_DBG("hcon %p conn %p hchan %p", hcon, conn, hchan);
6998
6999 switch (hcon->type) {
7000 case LE_LINK:
7001 if (hcon->hdev->le_mtu) {
7002 conn->mtu = hcon->hdev->le_mtu;
7003 break;
7004 }
7005 /* fall through */
7006 default:
7007 conn->mtu = hcon->hdev->acl_mtu;
7008 break;
7009 }
7010
7011 conn->feat_mask = 0;
7012
7013 conn->local_fixed_chan = L2CAP_FC_SIG_BREDR | L2CAP_FC_CONNLESS;
7014
7015 if (hcon->type == ACL_LINK &&
7016 hci_dev_test_flag(hcon->hdev, HCI_HS_ENABLED))
7017 conn->local_fixed_chan |= L2CAP_FC_A2MP;
7018
7019 if (hci_dev_test_flag(hcon->hdev, HCI_LE_ENABLED) &&
7020 (bredr_sc_enabled(hcon->hdev) ||
7021 hci_dev_test_flag(hcon->hdev, HCI_FORCE_BREDR_SMP)))
7022 conn->local_fixed_chan |= L2CAP_FC_SMP_BREDR;
7023
7024 mutex_init(&conn->ident_lock);
7025 mutex_init(&conn->chan_lock);
7026
7027 INIT_LIST_HEAD(&conn->chan_l);
7028 INIT_LIST_HEAD(&conn->users);
7029
7030 INIT_DELAYED_WORK(&conn->info_timer, l2cap_info_timeout);
7031
7032 skb_queue_head_init(&conn->pending_rx);
7033 INIT_WORK(&conn->pending_rx_work, process_pending_rx);
7034 INIT_WORK(&conn->id_addr_update_work, l2cap_conn_update_id_addr);
7035
7036 conn->disc_reason = HCI_ERROR_REMOTE_USER_TERM;
7037
7038 return conn;
7039 }
7040
7041 static bool is_valid_psm(u16 psm, u8 dst_type) {
7042 if (!psm)
7043 return false;
7044
7045 if (bdaddr_type_is_le(dst_type))
7046 return (psm <= 0x00ff);
7047
7048 /* PSM must be odd and lsb of upper byte must be 0 */
7049 return ((psm & 0x0101) == 0x0001);
7050 }
7051
7052 int l2cap_chan_connect(struct l2cap_chan *chan, __le16 psm, u16 cid,
7053 bdaddr_t *dst, u8 dst_type)
7054 {
7055 struct l2cap_conn *conn;
7056 struct hci_conn *hcon;
7057 struct hci_dev *hdev;
7058 int err;
7059
7060 BT_DBG("%pMR -> %pMR (type %u) psm 0x%2.2x", &chan->src, dst,
7061 dst_type, __le16_to_cpu(psm));
7062
7063 hdev = hci_get_route(dst, &chan->src);
7064 if (!hdev)
7065 return -EHOSTUNREACH;
7066
7067 hci_dev_lock(hdev);
7068
7069 if (!is_valid_psm(__le16_to_cpu(psm), dst_type) && !cid &&
7070 chan->chan_type != L2CAP_CHAN_RAW) {
7071 err = -EINVAL;
7072 goto done;
7073 }
7074
7075 if (chan->chan_type == L2CAP_CHAN_CONN_ORIENTED && !psm) {
7076 err = -EINVAL;
7077 goto done;
7078 }
7079
7080 if (chan->chan_type == L2CAP_CHAN_FIXED && !cid) {
7081 err = -EINVAL;
7082 goto done;
7083 }
7084
7085 switch (chan->mode) {
7086 case L2CAP_MODE_BASIC:
7087 break;
7088 case L2CAP_MODE_LE_FLOWCTL:
7089 l2cap_le_flowctl_init(chan);
7090 break;
7091 case L2CAP_MODE_ERTM:
7092 case L2CAP_MODE_STREAMING:
7093 if (!disable_ertm)
7094 break;
7095 /* fall through */
7096 default:
7097 err = -EOPNOTSUPP;
7098 goto done;
7099 }
7100
7101 switch (chan->state) {
7102 case BT_CONNECT:
7103 case BT_CONNECT2:
7104 case BT_CONFIG:
7105 /* Already connecting */
7106 err = 0;
7107 goto done;
7108
7109 case BT_CONNECTED:
7110 /* Already connected */
7111 err = -EISCONN;
7112 goto done;
7113
7114 case BT_OPEN:
7115 case BT_BOUND:
7116 /* Can connect */
7117 break;
7118
7119 default:
7120 err = -EBADFD;
7121 goto done;
7122 }
7123
7124 /* Set destination address and psm */
7125 bacpy(&chan->dst, dst);
7126 chan->dst_type = dst_type;
7127
7128 chan->psm = psm;
7129 chan->dcid = cid;
7130
7131 if (bdaddr_type_is_le(dst_type)) {
7132 /* Convert from L2CAP channel address type to HCI address type
7133 */
7134 if (dst_type == BDADDR_LE_PUBLIC)
7135 dst_type = ADDR_LE_DEV_PUBLIC;
7136 else
7137 dst_type = ADDR_LE_DEV_RANDOM;
7138
7139 if (hci_dev_test_flag(hdev, HCI_ADVERTISING))
7140 hcon = hci_connect_le(hdev, dst, dst_type,
7141 chan->sec_level,
7142 HCI_LE_CONN_TIMEOUT,
7143 HCI_ROLE_SLAVE);
7144 else
7145 hcon = hci_connect_le_scan(hdev, dst, dst_type,
7146 chan->sec_level,
7147 HCI_LE_CONN_TIMEOUT);
7148
7149 } else {
7150 u8 auth_type = l2cap_get_auth_type(chan);
7151 hcon = hci_connect_acl(hdev, dst, chan->sec_level, auth_type);
7152 }
7153
7154 if (IS_ERR(hcon)) {
7155 err = PTR_ERR(hcon);
7156 goto done;
7157 }
7158
7159 conn = l2cap_conn_add(hcon);
7160 if (!conn) {
7161 hci_conn_drop(hcon);
7162 err = -ENOMEM;
7163 goto done;
7164 }
7165
7166 mutex_lock(&conn->chan_lock);
7167 l2cap_chan_lock(chan);
7168
7169 if (cid && __l2cap_get_chan_by_dcid(conn, cid)) {
7170 hci_conn_drop(hcon);
7171 err = -EBUSY;
7172 goto chan_unlock;
7173 }
7174
7175 /* Update source addr of the socket */
7176 bacpy(&chan->src, &hcon->src);
7177 chan->src_type = bdaddr_src_type(hcon);
7178
7179 __l2cap_chan_add(conn, chan);
7180
7181 /* l2cap_chan_add takes its own ref so we can drop this one */
7182 hci_conn_drop(hcon);
7183
7184 l2cap_state_change(chan, BT_CONNECT);
7185 __set_chan_timer(chan, chan->ops->get_sndtimeo(chan));
7186
7187 /* Release chan->sport so that it can be reused by other
7188 * sockets (as it's only used for listening sockets).
7189 */
7190 write_lock(&chan_list_lock);
7191 chan->sport = 0;
7192 write_unlock(&chan_list_lock);
7193
7194 if (hcon->state == BT_CONNECTED) {
7195 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) {
7196 __clear_chan_timer(chan);
7197 if (l2cap_chan_check_security(chan, true))
7198 l2cap_state_change(chan, BT_CONNECTED);
7199 } else
7200 l2cap_do_start(chan);
7201 }
7202
7203 err = 0;
7204
7205 chan_unlock:
7206 l2cap_chan_unlock(chan);
7207 mutex_unlock(&conn->chan_lock);
7208 done:
7209 hci_dev_unlock(hdev);
7210 hci_dev_put(hdev);
7211 return err;
7212 }
7213 EXPORT_SYMBOL_GPL(l2cap_chan_connect);
7214
7215 /* ---- L2CAP interface with lower layer (HCI) ---- */
7216
7217 int l2cap_connect_ind(struct hci_dev *hdev, bdaddr_t *bdaddr)
7218 {
7219 int exact = 0, lm1 = 0, lm2 = 0;
7220 struct l2cap_chan *c;
7221
7222 BT_DBG("hdev %s, bdaddr %pMR", hdev->name, bdaddr);
7223
7224 /* Find listening sockets and check their link_mode */
7225 read_lock(&chan_list_lock);
7226 list_for_each_entry(c, &chan_list, global_l) {
7227 if (c->state != BT_LISTEN)
7228 continue;
7229
7230 if (!bacmp(&c->src, &hdev->bdaddr)) {
7231 lm1 |= HCI_LM_ACCEPT;
7232 if (test_bit(FLAG_ROLE_SWITCH, &c->flags))
7233 lm1 |= HCI_LM_MASTER;
7234 exact++;
7235 } else if (!bacmp(&c->src, BDADDR_ANY)) {
7236 lm2 |= HCI_LM_ACCEPT;
7237 if (test_bit(FLAG_ROLE_SWITCH, &c->flags))
7238 lm2 |= HCI_LM_MASTER;
7239 }
7240 }
7241 read_unlock(&chan_list_lock);
7242
7243 return exact ? lm1 : lm2;
7244 }
7245
7246 /* Find the next fixed channel in BT_LISTEN state, continue iteration
7247 * from an existing channel in the list or from the beginning of the
7248 * global list (by passing NULL as first parameter).
7249 */
7250 static struct l2cap_chan *l2cap_global_fixed_chan(struct l2cap_chan *c,
7251 struct hci_conn *hcon)
7252 {
7253 u8 src_type = bdaddr_src_type(hcon);
7254
7255 read_lock(&chan_list_lock);
7256
7257 if (c)
7258 c = list_next_entry(c, global_l);
7259 else
7260 c = list_entry(chan_list.next, typeof(*c), global_l);
7261
7262 list_for_each_entry_from(c, &chan_list, global_l) {
7263 if (c->chan_type != L2CAP_CHAN_FIXED)
7264 continue;
7265 if (c->state != BT_LISTEN)
7266 continue;
7267 if (bacmp(&c->src, &hcon->src) && bacmp(&c->src, BDADDR_ANY))
7268 continue;
7269 if (src_type != c->src_type)
7270 continue;
7271
7272 l2cap_chan_hold(c);
7273 read_unlock(&chan_list_lock);
7274 return c;
7275 }
7276
7277 read_unlock(&chan_list_lock);
7278
7279 return NULL;
7280 }
7281
7282 static void l2cap_connect_cfm(struct hci_conn *hcon, u8 status)
7283 {
7284 struct hci_dev *hdev = hcon->hdev;
7285 struct l2cap_conn *conn;
7286 struct l2cap_chan *pchan;
7287 u8 dst_type;
7288
7289 if (hcon->type != ACL_LINK && hcon->type != LE_LINK)
7290 return;
7291
7292 BT_DBG("hcon %p bdaddr %pMR status %d", hcon, &hcon->dst, status);
7293
7294 if (status) {
7295 l2cap_conn_del(hcon, bt_to_errno(status));
7296 return;
7297 }
7298
7299 conn = l2cap_conn_add(hcon);
7300 if (!conn)
7301 return;
7302
7303 dst_type = bdaddr_dst_type(hcon);
7304
7305 /* If device is blocked, do not create channels for it */
7306 if (hci_bdaddr_list_lookup(&hdev->blacklist, &hcon->dst, dst_type))
7307 return;
7308
7309 /* Find fixed channels and notify them of the new connection. We
7310 * use multiple individual lookups, continuing each time where
7311 * we left off, because the list lock would prevent calling the
7312 * potentially sleeping l2cap_chan_lock() function.
7313 */
7314 pchan = l2cap_global_fixed_chan(NULL, hcon);
7315 while (pchan) {
7316 struct l2cap_chan *chan, *next;
7317
7318 /* Client fixed channels should override server ones */
7319 if (__l2cap_get_chan_by_dcid(conn, pchan->scid))
7320 goto next;
7321
7322 l2cap_chan_lock(pchan);
7323 chan = pchan->ops->new_connection(pchan);
7324 if (chan) {
7325 bacpy(&chan->src, &hcon->src);
7326 bacpy(&chan->dst, &hcon->dst);
7327 chan->src_type = bdaddr_src_type(hcon);
7328 chan->dst_type = dst_type;
7329
7330 __l2cap_chan_add(conn, chan);
7331 }
7332
7333 l2cap_chan_unlock(pchan);
7334 next:
7335 next = l2cap_global_fixed_chan(pchan, hcon);
7336 l2cap_chan_put(pchan);
7337 pchan = next;
7338 }
7339
7340 l2cap_conn_ready(conn);
7341 }
7342
7343 int l2cap_disconn_ind(struct hci_conn *hcon)
7344 {
7345 struct l2cap_conn *conn = hcon->l2cap_data;
7346
7347 BT_DBG("hcon %p", hcon);
7348
7349 if (!conn)
7350 return HCI_ERROR_REMOTE_USER_TERM;
7351 return conn->disc_reason;
7352 }
7353
7354 static void l2cap_disconn_cfm(struct hci_conn *hcon, u8 reason)
7355 {
7356 if (hcon->type != ACL_LINK && hcon->type != LE_LINK)
7357 return;
7358
7359 BT_DBG("hcon %p reason %d", hcon, reason);
7360
7361 l2cap_conn_del(hcon, bt_to_errno(reason));
7362 }
7363
7364 static inline void l2cap_check_encryption(struct l2cap_chan *chan, u8 encrypt)
7365 {
7366 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED)
7367 return;
7368
7369 if (encrypt == 0x00) {
7370 if (chan->sec_level == BT_SECURITY_MEDIUM) {
7371 __set_chan_timer(chan, L2CAP_ENC_TIMEOUT);
7372 } else if (chan->sec_level == BT_SECURITY_HIGH ||
7373 chan->sec_level == BT_SECURITY_FIPS)
7374 l2cap_chan_close(chan, ECONNREFUSED);
7375 } else {
7376 if (chan->sec_level == BT_SECURITY_MEDIUM)
7377 __clear_chan_timer(chan);
7378 }
7379 }
7380
7381 static void l2cap_security_cfm(struct hci_conn *hcon, u8 status, u8 encrypt)
7382 {
7383 struct l2cap_conn *conn = hcon->l2cap_data;
7384 struct l2cap_chan *chan;
7385
7386 if (!conn)
7387 return;
7388
7389 BT_DBG("conn %p status 0x%2.2x encrypt %u", conn, status, encrypt);
7390
7391 mutex_lock(&conn->chan_lock);
7392
7393 list_for_each_entry(chan, &conn->chan_l, list) {
7394 l2cap_chan_lock(chan);
7395
7396 BT_DBG("chan %p scid 0x%4.4x state %s", chan, chan->scid,
7397 state_to_string(chan->state));
7398
7399 if (chan->scid == L2CAP_CID_A2MP) {
7400 l2cap_chan_unlock(chan);
7401 continue;
7402 }
7403
7404 if (!status && encrypt)
7405 chan->sec_level = hcon->sec_level;
7406
7407 if (!__l2cap_no_conn_pending(chan)) {
7408 l2cap_chan_unlock(chan);
7409 continue;
7410 }
7411
7412 if (!status && (chan->state == BT_CONNECTED ||
7413 chan->state == BT_CONFIG)) {
7414 chan->ops->resume(chan);
7415 l2cap_check_encryption(chan, encrypt);
7416 l2cap_chan_unlock(chan);
7417 continue;
7418 }
7419
7420 if (chan->state == BT_CONNECT) {
7421 if (!status)
7422 l2cap_start_connection(chan);
7423 else
7424 __set_chan_timer(chan, L2CAP_DISC_TIMEOUT);
7425 } else if (chan->state == BT_CONNECT2 &&
7426 chan->mode != L2CAP_MODE_LE_FLOWCTL) {
7427 struct l2cap_conn_rsp rsp;
7428 __u16 res, stat;
7429
7430 if (!status) {
7431 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) {
7432 res = L2CAP_CR_PEND;
7433 stat = L2CAP_CS_AUTHOR_PEND;
7434 chan->ops->defer(chan);
7435 } else {
7436 l2cap_state_change(chan, BT_CONFIG);
7437 res = L2CAP_CR_SUCCESS;
7438 stat = L2CAP_CS_NO_INFO;
7439 }
7440 } else {
7441 l2cap_state_change(chan, BT_DISCONN);
7442 __set_chan_timer(chan, L2CAP_DISC_TIMEOUT);
7443 res = L2CAP_CR_SEC_BLOCK;
7444 stat = L2CAP_CS_NO_INFO;
7445 }
7446
7447 rsp.scid = cpu_to_le16(chan->dcid);
7448 rsp.dcid = cpu_to_le16(chan->scid);
7449 rsp.result = cpu_to_le16(res);
7450 rsp.status = cpu_to_le16(stat);
7451 l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_RSP,
7452 sizeof(rsp), &rsp);
7453
7454 if (!test_bit(CONF_REQ_SENT, &chan->conf_state) &&
7455 res == L2CAP_CR_SUCCESS) {
7456 char buf[128];
7457 set_bit(CONF_REQ_SENT, &chan->conf_state);
7458 l2cap_send_cmd(conn, l2cap_get_ident(conn),
7459 L2CAP_CONF_REQ,
7460 l2cap_build_conf_req(chan, buf),
7461 buf);
7462 chan->num_conf_req++;
7463 }
7464 }
7465
7466 l2cap_chan_unlock(chan);
7467 }
7468
7469 mutex_unlock(&conn->chan_lock);
7470 }
7471
7472 void l2cap_recv_acldata(struct hci_conn *hcon, struct sk_buff *skb, u16 flags)
7473 {
7474 struct l2cap_conn *conn = hcon->l2cap_data;
7475 struct l2cap_hdr *hdr;
7476 int len;
7477
7478 /* For AMP controller do not create l2cap conn */
7479 if (!conn && hcon->hdev->dev_type != HCI_PRIMARY)
7480 goto drop;
7481
7482 if (!conn)
7483 conn = l2cap_conn_add(hcon);
7484
7485 if (!conn)
7486 goto drop;
7487
7488 BT_DBG("conn %p len %d flags 0x%x", conn, skb->len, flags);
7489
7490 switch (flags) {
7491 case ACL_START:
7492 case ACL_START_NO_FLUSH:
7493 case ACL_COMPLETE:
7494 if (conn->rx_len) {
7495 BT_ERR("Unexpected start frame (len %d)", skb->len);
7496 kfree_skb(conn->rx_skb);
7497 conn->rx_skb = NULL;
7498 conn->rx_len = 0;
7499 l2cap_conn_unreliable(conn, ECOMM);
7500 }
7501
7502 /* Start fragment always begin with Basic L2CAP header */
7503 if (skb->len < L2CAP_HDR_SIZE) {
7504 BT_ERR("Frame is too short (len %d)", skb->len);
7505 l2cap_conn_unreliable(conn, ECOMM);
7506 goto drop;
7507 }
7508
7509 hdr = (struct l2cap_hdr *) skb->data;
7510 len = __le16_to_cpu(hdr->len) + L2CAP_HDR_SIZE;
7511
7512 if (len == skb->len) {
7513 /* Complete frame received */
7514 l2cap_recv_frame(conn, skb);
7515 return;
7516 }
7517
7518 BT_DBG("Start: total len %d, frag len %d", len, skb->len);
7519
7520 if (skb->len > len) {
7521 BT_ERR("Frame is too long (len %d, expected len %d)",
7522 skb->len, len);
7523 l2cap_conn_unreliable(conn, ECOMM);
7524 goto drop;
7525 }
7526
7527 /* Allocate skb for the complete frame (with header) */
7528 conn->rx_skb = bt_skb_alloc(len, GFP_KERNEL);
7529 if (!conn->rx_skb)
7530 goto drop;
7531
7532 skb_copy_from_linear_data(skb, skb_put(conn->rx_skb, skb->len),
7533 skb->len);
7534 conn->rx_len = len - skb->len;
7535 break;
7536
7537 case ACL_CONT:
7538 BT_DBG("Cont: frag len %d (expecting %d)", skb->len, conn->rx_len);
7539
7540 if (!conn->rx_len) {
7541 BT_ERR("Unexpected continuation frame (len %d)", skb->len);
7542 l2cap_conn_unreliable(conn, ECOMM);
7543 goto drop;
7544 }
7545
7546 if (skb->len > conn->rx_len) {
7547 BT_ERR("Fragment is too long (len %d, expected %d)",
7548 skb->len, conn->rx_len);
7549 kfree_skb(conn->rx_skb);
7550 conn->rx_skb = NULL;
7551 conn->rx_len = 0;
7552 l2cap_conn_unreliable(conn, ECOMM);
7553 goto drop;
7554 }
7555
7556 skb_copy_from_linear_data(skb, skb_put(conn->rx_skb, skb->len),
7557 skb->len);
7558 conn->rx_len -= skb->len;
7559
7560 if (!conn->rx_len) {
7561 /* Complete frame received. l2cap_recv_frame
7562 * takes ownership of the skb so set the global
7563 * rx_skb pointer to NULL first.
7564 */
7565 struct sk_buff *rx_skb = conn->rx_skb;
7566 conn->rx_skb = NULL;
7567 l2cap_recv_frame(conn, rx_skb);
7568 }
7569 break;
7570 }
7571
7572 drop:
7573 kfree_skb(skb);
7574 }
7575
7576 static struct hci_cb l2cap_cb = {
7577 .name = "L2CAP",
7578 .connect_cfm = l2cap_connect_cfm,
7579 .disconn_cfm = l2cap_disconn_cfm,
7580 .security_cfm = l2cap_security_cfm,
7581 };
7582
7583 static int l2cap_debugfs_show(struct seq_file *f, void *p)
7584 {
7585 struct l2cap_chan *c;
7586
7587 read_lock(&chan_list_lock);
7588
7589 list_for_each_entry(c, &chan_list, global_l) {
7590 seq_printf(f, "%pMR (%u) %pMR (%u) %d %d 0x%4.4x 0x%4.4x %d %d %d %d\n",
7591 &c->src, c->src_type, &c->dst, c->dst_type,
7592 c->state, __le16_to_cpu(c->psm),
7593 c->scid, c->dcid, c->imtu, c->omtu,
7594 c->sec_level, c->mode);
7595 }
7596
7597 read_unlock(&chan_list_lock);
7598
7599 return 0;
7600 }
7601
7602 static int l2cap_debugfs_open(struct inode *inode, struct file *file)
7603 {
7604 return single_open(file, l2cap_debugfs_show, inode->i_private);
7605 }
7606
7607 static const struct file_operations l2cap_debugfs_fops = {
7608 .open = l2cap_debugfs_open,
7609 .read = seq_read,
7610 .llseek = seq_lseek,
7611 .release = single_release,
7612 };
7613
7614 static struct dentry *l2cap_debugfs;
7615
7616 int __init l2cap_init(void)
7617 {
7618 int err;
7619
7620 err = l2cap_init_sockets();
7621 if (err < 0)
7622 return err;
7623
7624 hci_register_cb(&l2cap_cb);
7625
7626 if (IS_ERR_OR_NULL(bt_debugfs))
7627 return 0;
7628
7629 l2cap_debugfs = debugfs_create_file("l2cap", 0444, bt_debugfs,
7630 NULL, &l2cap_debugfs_fops);
7631
7632 debugfs_create_u16("l2cap_le_max_credits", 0644, bt_debugfs,
7633 &le_max_credits);
7634 debugfs_create_u16("l2cap_le_default_mps", 0644, bt_debugfs,
7635 &le_default_mps);
7636
7637 return 0;
7638 }
7639
7640 void l2cap_exit(void)
7641 {
7642 debugfs_remove(l2cap_debugfs);
7643 hci_unregister_cb(&l2cap_cb);
7644 l2cap_cleanup_sockets();
7645 }
7646
7647 module_param(disable_ertm, bool, 0644);
7648 MODULE_PARM_DESC(disable_ertm, "Disable enhanced retransmission mode");
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