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drm/i915: Check incoming alignment for unfenced buffers (on i915gm)
[linux-stable.git] / net / bluetooth / l2cap_core.c
blob43ba91c440bcd65bd9f24258a28d01492cf6ac13
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, size_t data_size);
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, kref_read(&c->kref));
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, kref_read(&c->kref));
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 = 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, sizeof(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_full(skb_put(skb, count), count, &msg->msg_iter))
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_full(skb_put(*frag, count), count,
2151 &msg->msg_iter))
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 = 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 = 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 = 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 = 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 static void l2cap_le_flowctl_send(struct l2cap_chan *chan)
2429 {
2430 int sent = 0;
2431
2432 BT_DBG("chan %p", chan);
2433
2434 while (chan->tx_credits && !skb_queue_empty(&chan->tx_q)) {
2435 l2cap_do_send(chan, skb_dequeue(&chan->tx_q));
2436 chan->tx_credits--;
2437 sent++;
2438 }
2439
2440 BT_DBG("Sent %d credits %u queued %u", sent, chan->tx_credits,
2441 skb_queue_len(&chan->tx_q));
2442 }
2443
2444 int l2cap_chan_send(struct l2cap_chan *chan, struct msghdr *msg, size_t len)
2445 {
2446 struct sk_buff *skb;
2447 int err;
2448 struct sk_buff_head seg_queue;
2449
2450 if (!chan->conn)
2451 return -ENOTCONN;
2452
2453 /* Connectionless channel */
2454 if (chan->chan_type == L2CAP_CHAN_CONN_LESS) {
2455 skb = l2cap_create_connless_pdu(chan, msg, len);
2456 if (IS_ERR(skb))
2457 return PTR_ERR(skb);
2458
2459 /* Channel lock is released before requesting new skb and then
2460 * reacquired thus we need to recheck channel state.
2461 */
2462 if (chan->state != BT_CONNECTED) {
2463 kfree_skb(skb);
2464 return -ENOTCONN;
2465 }
2466
2467 l2cap_do_send(chan, skb);
2468 return len;
2469 }
2470
2471 switch (chan->mode) {
2472 case L2CAP_MODE_LE_FLOWCTL:
2473 /* Check outgoing MTU */
2474 if (len > chan->omtu)
2475 return -EMSGSIZE;
2476
2477 __skb_queue_head_init(&seg_queue);
2478
2479 err = l2cap_segment_le_sdu(chan, &seg_queue, msg, len);
2480
2481 if (chan->state != BT_CONNECTED) {
2482 __skb_queue_purge(&seg_queue);
2483 err = -ENOTCONN;
2484 }
2485
2486 if (err)
2487 return err;
2488
2489 skb_queue_splice_tail_init(&seg_queue, &chan->tx_q);
2490
2491 l2cap_le_flowctl_send(chan);
2492
2493 if (!chan->tx_credits)
2494 chan->ops->suspend(chan);
2495
2496 err = len;
2497
2498 break;
2499
2500 case L2CAP_MODE_BASIC:
2501 /* Check outgoing MTU */
2502 if (len > chan->omtu)
2503 return -EMSGSIZE;
2504
2505 /* Create a basic PDU */
2506 skb = l2cap_create_basic_pdu(chan, msg, len);
2507 if (IS_ERR(skb))
2508 return PTR_ERR(skb);
2509
2510 /* Channel lock is released before requesting new skb and then
2511 * reacquired thus we need to recheck channel state.
2512 */
2513 if (chan->state != BT_CONNECTED) {
2514 kfree_skb(skb);
2515 return -ENOTCONN;
2516 }
2517
2518 l2cap_do_send(chan, skb);
2519 err = len;
2520 break;
2521
2522 case L2CAP_MODE_ERTM:
2523 case L2CAP_MODE_STREAMING:
2524 /* Check outgoing MTU */
2525 if (len > chan->omtu) {
2526 err = -EMSGSIZE;
2527 break;
2528 }
2529
2530 __skb_queue_head_init(&seg_queue);
2531
2532 /* Do segmentation before calling in to the state machine,
2533 * since it's possible to block while waiting for memory
2534 * allocation.
2535 */
2536 err = l2cap_segment_sdu(chan, &seg_queue, msg, len);
2537
2538 /* The channel could have been closed while segmenting,
2539 * check that it is still connected.
2540 */
2541 if (chan->state != BT_CONNECTED) {
2542 __skb_queue_purge(&seg_queue);
2543 err = -ENOTCONN;
2544 }
2545
2546 if (err)
2547 break;
2548
2549 if (chan->mode == L2CAP_MODE_ERTM)
2550 l2cap_tx(chan, NULL, &seg_queue, L2CAP_EV_DATA_REQUEST);
2551 else
2552 l2cap_streaming_send(chan, &seg_queue);
2553
2554 err = len;
2555
2556 /* If the skbs were not queued for sending, they'll still be in
2557 * seg_queue and need to be purged.
2558 */
2559 __skb_queue_purge(&seg_queue);
2560 break;
2561
2562 default:
2563 BT_DBG("bad state %1.1x", chan->mode);
2564 err = -EBADFD;
2565 }
2566
2567 return err;
2568 }
2569 EXPORT_SYMBOL_GPL(l2cap_chan_send);
2570
2571 static void l2cap_send_srej(struct l2cap_chan *chan, u16 txseq)
2572 {
2573 struct l2cap_ctrl control;
2574 u16 seq;
2575
2576 BT_DBG("chan %p, txseq %u", chan, txseq);
2577
2578 memset(&control, 0, sizeof(control));
2579 control.sframe = 1;
2580 control.super = L2CAP_SUPER_SREJ;
2581
2582 for (seq = chan->expected_tx_seq; seq != txseq;
2583 seq = __next_seq(chan, seq)) {
2584 if (!l2cap_ertm_seq_in_queue(&chan->srej_q, seq)) {
2585 control.reqseq = seq;
2586 l2cap_send_sframe(chan, &control);
2587 l2cap_seq_list_append(&chan->srej_list, seq);
2588 }
2589 }
2590
2591 chan->expected_tx_seq = __next_seq(chan, txseq);
2592 }
2593
2594 static void l2cap_send_srej_tail(struct l2cap_chan *chan)
2595 {
2596 struct l2cap_ctrl control;
2597
2598 BT_DBG("chan %p", chan);
2599
2600 if (chan->srej_list.tail == L2CAP_SEQ_LIST_CLEAR)
2601 return;
2602
2603 memset(&control, 0, sizeof(control));
2604 control.sframe = 1;
2605 control.super = L2CAP_SUPER_SREJ;
2606 control.reqseq = chan->srej_list.tail;
2607 l2cap_send_sframe(chan, &control);
2608 }
2609
2610 static void l2cap_send_srej_list(struct l2cap_chan *chan, u16 txseq)
2611 {
2612 struct l2cap_ctrl control;
2613 u16 initial_head;
2614 u16 seq;
2615
2616 BT_DBG("chan %p, txseq %u", chan, txseq);
2617
2618 memset(&control, 0, sizeof(control));
2619 control.sframe = 1;
2620 control.super = L2CAP_SUPER_SREJ;
2621
2622 /* Capture initial list head to allow only one pass through the list. */
2623 initial_head = chan->srej_list.head;
2624
2625 do {
2626 seq = l2cap_seq_list_pop(&chan->srej_list);
2627 if (seq == txseq || seq == L2CAP_SEQ_LIST_CLEAR)
2628 break;
2629
2630 control.reqseq = seq;
2631 l2cap_send_sframe(chan, &control);
2632 l2cap_seq_list_append(&chan->srej_list, seq);
2633 } while (chan->srej_list.head != initial_head);
2634 }
2635
2636 static void l2cap_process_reqseq(struct l2cap_chan *chan, u16 reqseq)
2637 {
2638 struct sk_buff *acked_skb;
2639 u16 ackseq;
2640
2641 BT_DBG("chan %p, reqseq %u", chan, reqseq);
2642
2643 if (chan->unacked_frames == 0 || reqseq == chan->expected_ack_seq)
2644 return;
2645
2646 BT_DBG("expected_ack_seq %u, unacked_frames %u",
2647 chan->expected_ack_seq, chan->unacked_frames);
2648
2649 for (ackseq = chan->expected_ack_seq; ackseq != reqseq;
2650 ackseq = __next_seq(chan, ackseq)) {
2651
2652 acked_skb = l2cap_ertm_seq_in_queue(&chan->tx_q, ackseq);
2653 if (acked_skb) {
2654 skb_unlink(acked_skb, &chan->tx_q);
2655 kfree_skb(acked_skb);
2656 chan->unacked_frames--;
2657 }
2658 }
2659
2660 chan->expected_ack_seq = reqseq;
2661
2662 if (chan->unacked_frames == 0)
2663 __clear_retrans_timer(chan);
2664
2665 BT_DBG("unacked_frames %u", chan->unacked_frames);
2666 }
2667
2668 static void l2cap_abort_rx_srej_sent(struct l2cap_chan *chan)
2669 {
2670 BT_DBG("chan %p", chan);
2671
2672 chan->expected_tx_seq = chan->buffer_seq;
2673 l2cap_seq_list_clear(&chan->srej_list);
2674 skb_queue_purge(&chan->srej_q);
2675 chan->rx_state = L2CAP_RX_STATE_RECV;
2676 }
2677
2678 static void l2cap_tx_state_xmit(struct l2cap_chan *chan,
2679 struct l2cap_ctrl *control,
2680 struct sk_buff_head *skbs, u8 event)
2681 {
2682 BT_DBG("chan %p, control %p, skbs %p, event %d", chan, control, skbs,
2683 event);
2684
2685 switch (event) {
2686 case L2CAP_EV_DATA_REQUEST:
2687 if (chan->tx_send_head == NULL)
2688 chan->tx_send_head = skb_peek(skbs);
2689
2690 skb_queue_splice_tail_init(skbs, &chan->tx_q);
2691 l2cap_ertm_send(chan);
2692 break;
2693 case L2CAP_EV_LOCAL_BUSY_DETECTED:
2694 BT_DBG("Enter LOCAL_BUSY");
2695 set_bit(CONN_LOCAL_BUSY, &chan->conn_state);
2696
2697 if (chan->rx_state == L2CAP_RX_STATE_SREJ_SENT) {
2698 /* The SREJ_SENT state must be aborted if we are to
2699 * enter the LOCAL_BUSY state.
2700 */
2701 l2cap_abort_rx_srej_sent(chan);
2702 }
2703
2704 l2cap_send_ack(chan);
2705
2706 break;
2707 case L2CAP_EV_LOCAL_BUSY_CLEAR:
2708 BT_DBG("Exit LOCAL_BUSY");
2709 clear_bit(CONN_LOCAL_BUSY, &chan->conn_state);
2710
2711 if (test_bit(CONN_RNR_SENT, &chan->conn_state)) {
2712 struct l2cap_ctrl local_control;
2713
2714 memset(&local_control, 0, sizeof(local_control));
2715 local_control.sframe = 1;
2716 local_control.super = L2CAP_SUPER_RR;
2717 local_control.poll = 1;
2718 local_control.reqseq = chan->buffer_seq;
2719 l2cap_send_sframe(chan, &local_control);
2720
2721 chan->retry_count = 1;
2722 __set_monitor_timer(chan);
2723 chan->tx_state = L2CAP_TX_STATE_WAIT_F;
2724 }
2725 break;
2726 case L2CAP_EV_RECV_REQSEQ_AND_FBIT:
2727 l2cap_process_reqseq(chan, control->reqseq);
2728 break;
2729 case L2CAP_EV_EXPLICIT_POLL:
2730 l2cap_send_rr_or_rnr(chan, 1);
2731 chan->retry_count = 1;
2732 __set_monitor_timer(chan);
2733 __clear_ack_timer(chan);
2734 chan->tx_state = L2CAP_TX_STATE_WAIT_F;
2735 break;
2736 case L2CAP_EV_RETRANS_TO:
2737 l2cap_send_rr_or_rnr(chan, 1);
2738 chan->retry_count = 1;
2739 __set_monitor_timer(chan);
2740 chan->tx_state = L2CAP_TX_STATE_WAIT_F;
2741 break;
2742 case L2CAP_EV_RECV_FBIT:
2743 /* Nothing to process */
2744 break;
2745 default:
2746 break;
2747 }
2748 }
2749
2750 static void l2cap_tx_state_wait_f(struct l2cap_chan *chan,
2751 struct l2cap_ctrl *control,
2752 struct sk_buff_head *skbs, u8 event)
2753 {
2754 BT_DBG("chan %p, control %p, skbs %p, event %d", chan, control, skbs,
2755 event);
2756
2757 switch (event) {
2758 case L2CAP_EV_DATA_REQUEST:
2759 if (chan->tx_send_head == NULL)
2760 chan->tx_send_head = skb_peek(skbs);
2761 /* Queue data, but don't send. */
2762 skb_queue_splice_tail_init(skbs, &chan->tx_q);
2763 break;
2764 case L2CAP_EV_LOCAL_BUSY_DETECTED:
2765 BT_DBG("Enter LOCAL_BUSY");
2766 set_bit(CONN_LOCAL_BUSY, &chan->conn_state);
2767
2768 if (chan->rx_state == L2CAP_RX_STATE_SREJ_SENT) {
2769 /* The SREJ_SENT state must be aborted if we are to
2770 * enter the LOCAL_BUSY state.
2771 */
2772 l2cap_abort_rx_srej_sent(chan);
2773 }
2774
2775 l2cap_send_ack(chan);
2776
2777 break;
2778 case L2CAP_EV_LOCAL_BUSY_CLEAR:
2779 BT_DBG("Exit LOCAL_BUSY");
2780 clear_bit(CONN_LOCAL_BUSY, &chan->conn_state);
2781
2782 if (test_bit(CONN_RNR_SENT, &chan->conn_state)) {
2783 struct l2cap_ctrl local_control;
2784 memset(&local_control, 0, sizeof(local_control));
2785 local_control.sframe = 1;
2786 local_control.super = L2CAP_SUPER_RR;
2787 local_control.poll = 1;
2788 local_control.reqseq = chan->buffer_seq;
2789 l2cap_send_sframe(chan, &local_control);
2790
2791 chan->retry_count = 1;
2792 __set_monitor_timer(chan);
2793 chan->tx_state = L2CAP_TX_STATE_WAIT_F;
2794 }
2795 break;
2796 case L2CAP_EV_RECV_REQSEQ_AND_FBIT:
2797 l2cap_process_reqseq(chan, control->reqseq);
2798
2799 /* Fall through */
2800
2801 case L2CAP_EV_RECV_FBIT:
2802 if (control && control->final) {
2803 __clear_monitor_timer(chan);
2804 if (chan->unacked_frames > 0)
2805 __set_retrans_timer(chan);
2806 chan->retry_count = 0;
2807 chan->tx_state = L2CAP_TX_STATE_XMIT;
2808 BT_DBG("recv fbit tx_state 0x2.2%x", chan->tx_state);
2809 }
2810 break;
2811 case L2CAP_EV_EXPLICIT_POLL:
2812 /* Ignore */
2813 break;
2814 case L2CAP_EV_MONITOR_TO:
2815 if (chan->max_tx == 0 || chan->retry_count < chan->max_tx) {
2816 l2cap_send_rr_or_rnr(chan, 1);
2817 __set_monitor_timer(chan);
2818 chan->retry_count++;
2819 } else {
2820 l2cap_send_disconn_req(chan, ECONNABORTED);
2821 }
2822 break;
2823 default:
2824 break;
2825 }
2826 }
2827
2828 static void l2cap_tx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
2829 struct sk_buff_head *skbs, u8 event)
2830 {
2831 BT_DBG("chan %p, control %p, skbs %p, event %d, state %d",
2832 chan, control, skbs, event, chan->tx_state);
2833
2834 switch (chan->tx_state) {
2835 case L2CAP_TX_STATE_XMIT:
2836 l2cap_tx_state_xmit(chan, control, skbs, event);
2837 break;
2838 case L2CAP_TX_STATE_WAIT_F:
2839 l2cap_tx_state_wait_f(chan, control, skbs, event);
2840 break;
2841 default:
2842 /* Ignore event */
2843 break;
2844 }
2845 }
2846
2847 static void l2cap_pass_to_tx(struct l2cap_chan *chan,
2848 struct l2cap_ctrl *control)
2849 {
2850 BT_DBG("chan %p, control %p", chan, control);
2851 l2cap_tx(chan, control, NULL, L2CAP_EV_RECV_REQSEQ_AND_FBIT);
2852 }
2853
2854 static void l2cap_pass_to_tx_fbit(struct l2cap_chan *chan,
2855 struct l2cap_ctrl *control)
2856 {
2857 BT_DBG("chan %p, control %p", chan, control);
2858 l2cap_tx(chan, control, NULL, L2CAP_EV_RECV_FBIT);
2859 }
2860
2861 /* Copy frame to all raw sockets on that connection */
2862 static void l2cap_raw_recv(struct l2cap_conn *conn, struct sk_buff *skb)
2863 {
2864 struct sk_buff *nskb;
2865 struct l2cap_chan *chan;
2866
2867 BT_DBG("conn %p", conn);
2868
2869 mutex_lock(&conn->chan_lock);
2870
2871 list_for_each_entry(chan, &conn->chan_l, list) {
2872 if (chan->chan_type != L2CAP_CHAN_RAW)
2873 continue;
2874
2875 /* Don't send frame to the channel it came from */
2876 if (bt_cb(skb)->l2cap.chan == chan)
2877 continue;
2878
2879 nskb = skb_clone(skb, GFP_KERNEL);
2880 if (!nskb)
2881 continue;
2882 if (chan->ops->recv(chan, nskb))
2883 kfree_skb(nskb);
2884 }
2885
2886 mutex_unlock(&conn->chan_lock);
2887 }
2888
2889 /* ---- L2CAP signalling commands ---- */
2890 static struct sk_buff *l2cap_build_cmd(struct l2cap_conn *conn, u8 code,
2891 u8 ident, u16 dlen, void *data)
2892 {
2893 struct sk_buff *skb, **frag;
2894 struct l2cap_cmd_hdr *cmd;
2895 struct l2cap_hdr *lh;
2896 int len, count;
2897
2898 BT_DBG("conn %p, code 0x%2.2x, ident 0x%2.2x, len %u",
2899 conn, code, ident, dlen);
2900
2901 if (conn->mtu < L2CAP_HDR_SIZE + L2CAP_CMD_HDR_SIZE)
2902 return NULL;
2903
2904 len = L2CAP_HDR_SIZE + L2CAP_CMD_HDR_SIZE + dlen;
2905 count = min_t(unsigned int, conn->mtu, len);
2906
2907 skb = bt_skb_alloc(count, GFP_KERNEL);
2908 if (!skb)
2909 return NULL;
2910
2911 lh = skb_put(skb, L2CAP_HDR_SIZE);
2912 lh->len = cpu_to_le16(L2CAP_CMD_HDR_SIZE + dlen);
2913
2914 if (conn->hcon->type == LE_LINK)
2915 lh->cid = cpu_to_le16(L2CAP_CID_LE_SIGNALING);
2916 else
2917 lh->cid = cpu_to_le16(L2CAP_CID_SIGNALING);
2918
2919 cmd = skb_put(skb, L2CAP_CMD_HDR_SIZE);
2920 cmd->code = code;
2921 cmd->ident = ident;
2922 cmd->len = cpu_to_le16(dlen);
2923
2924 if (dlen) {
2925 count -= L2CAP_HDR_SIZE + L2CAP_CMD_HDR_SIZE;
2926 skb_put_data(skb, data, count);
2927 data += count;
2928 }
2929
2930 len -= skb->len;
2931
2932 /* Continuation fragments (no L2CAP header) */
2933 frag = &skb_shinfo(skb)->frag_list;
2934 while (len) {
2935 count = min_t(unsigned int, conn->mtu, len);
2936
2937 *frag = bt_skb_alloc(count, GFP_KERNEL);
2938 if (!*frag)
2939 goto fail;
2940
2941 skb_put_data(*frag, data, count);
2942
2943 len -= count;
2944 data += count;
2945
2946 frag = &(*frag)->next;
2947 }
2948
2949 return skb;
2950
2951 fail:
2952 kfree_skb(skb);
2953 return NULL;
2954 }
2955
2956 static inline int l2cap_get_conf_opt(void **ptr, int *type, int *olen,
2957 unsigned long *val)
2958 {
2959 struct l2cap_conf_opt *opt = *ptr;
2960 int len;
2961
2962 len = L2CAP_CONF_OPT_SIZE + opt->len;
2963 *ptr += len;
2964
2965 *type = opt->type;
2966 *olen = opt->len;
2967
2968 switch (opt->len) {
2969 case 1:
2970 *val = *((u8 *) opt->val);
2971 break;
2972
2973 case 2:
2974 *val = get_unaligned_le16(opt->val);
2975 break;
2976
2977 case 4:
2978 *val = get_unaligned_le32(opt->val);
2979 break;
2980
2981 default:
2982 *val = (unsigned long) opt->val;
2983 break;
2984 }
2985
2986 BT_DBG("type 0x%2.2x len %u val 0x%lx", *type, opt->len, *val);
2987 return len;
2988 }
2989
2990 static void l2cap_add_conf_opt(void **ptr, u8 type, u8 len, unsigned long val, size_t size)
2991 {
2992 struct l2cap_conf_opt *opt = *ptr;
2993
2994 BT_DBG("type 0x%2.2x len %u val 0x%lx", type, len, val);
2995
2996 if (size < L2CAP_CONF_OPT_SIZE + len)
2997 return;
2998
2999 opt->type = type;
3000 opt->len = len;
3001
3002 switch (len) {
3003 case 1:
3004 *((u8 *) opt->val) = val;
3005 break;
3006
3007 case 2:
3008 put_unaligned_le16(val, opt->val);
3009 break;
3010
3011 case 4:
3012 put_unaligned_le32(val, opt->val);
3013 break;
3014
3015 default:
3016 memcpy(opt->val, (void *) val, len);
3017 break;
3018 }
3019
3020 *ptr += L2CAP_CONF_OPT_SIZE + len;
3021 }
3022
3023 static void l2cap_add_opt_efs(void **ptr, struct l2cap_chan *chan, size_t size)
3024 {
3025 struct l2cap_conf_efs efs;
3026
3027 switch (chan->mode) {
3028 case L2CAP_MODE_ERTM:
3029 efs.id = chan->local_id;
3030 efs.stype = chan->local_stype;
3031 efs.msdu = cpu_to_le16(chan->local_msdu);
3032 efs.sdu_itime = cpu_to_le32(chan->local_sdu_itime);
3033 efs.acc_lat = cpu_to_le32(L2CAP_DEFAULT_ACC_LAT);
3034 efs.flush_to = cpu_to_le32(L2CAP_EFS_DEFAULT_FLUSH_TO);
3035 break;
3036
3037 case L2CAP_MODE_STREAMING:
3038 efs.id = 1;
3039 efs.stype = L2CAP_SERV_BESTEFFORT;
3040 efs.msdu = cpu_to_le16(chan->local_msdu);
3041 efs.sdu_itime = cpu_to_le32(chan->local_sdu_itime);
3042 efs.acc_lat = 0;
3043 efs.flush_to = 0;
3044 break;
3045
3046 default:
3047 return;
3048 }
3049
3050 l2cap_add_conf_opt(ptr, L2CAP_CONF_EFS, sizeof(efs),
3051 (unsigned long) &efs, size);
3052 }
3053
3054 static void l2cap_ack_timeout(struct work_struct *work)
3055 {
3056 struct l2cap_chan *chan = container_of(work, struct l2cap_chan,
3057 ack_timer.work);
3058 u16 frames_to_ack;
3059
3060 BT_DBG("chan %p", chan);
3061
3062 l2cap_chan_lock(chan);
3063
3064 frames_to_ack = __seq_offset(chan, chan->buffer_seq,
3065 chan->last_acked_seq);
3066
3067 if (frames_to_ack)
3068 l2cap_send_rr_or_rnr(chan, 0);
3069
3070 l2cap_chan_unlock(chan);
3071 l2cap_chan_put(chan);
3072 }
3073
3074 int l2cap_ertm_init(struct l2cap_chan *chan)
3075 {
3076 int err;
3077
3078 chan->next_tx_seq = 0;
3079 chan->expected_tx_seq = 0;
3080 chan->expected_ack_seq = 0;
3081 chan->unacked_frames = 0;
3082 chan->buffer_seq = 0;
3083 chan->frames_sent = 0;
3084 chan->last_acked_seq = 0;
3085 chan->sdu = NULL;
3086 chan->sdu_last_frag = NULL;
3087 chan->sdu_len = 0;
3088
3089 skb_queue_head_init(&chan->tx_q);
3090
3091 chan->local_amp_id = AMP_ID_BREDR;
3092 chan->move_id = AMP_ID_BREDR;
3093 chan->move_state = L2CAP_MOVE_STABLE;
3094 chan->move_role = L2CAP_MOVE_ROLE_NONE;
3095
3096 if (chan->mode != L2CAP_MODE_ERTM)
3097 return 0;
3098
3099 chan->rx_state = L2CAP_RX_STATE_RECV;
3100 chan->tx_state = L2CAP_TX_STATE_XMIT;
3101
3102 INIT_DELAYED_WORK(&chan->retrans_timer, l2cap_retrans_timeout);
3103 INIT_DELAYED_WORK(&chan->monitor_timer, l2cap_monitor_timeout);
3104 INIT_DELAYED_WORK(&chan->ack_timer, l2cap_ack_timeout);
3105
3106 skb_queue_head_init(&chan->srej_q);
3107
3108 err = l2cap_seq_list_init(&chan->srej_list, chan->tx_win);
3109 if (err < 0)
3110 return err;
3111
3112 err = l2cap_seq_list_init(&chan->retrans_list, chan->remote_tx_win);
3113 if (err < 0)
3114 l2cap_seq_list_free(&chan->srej_list);
3115
3116 return err;
3117 }
3118
3119 static inline __u8 l2cap_select_mode(__u8 mode, __u16 remote_feat_mask)
3120 {
3121 switch (mode) {
3122 case L2CAP_MODE_STREAMING:
3123 case L2CAP_MODE_ERTM:
3124 if (l2cap_mode_supported(mode, remote_feat_mask))
3125 return mode;
3126 /* fall through */
3127 default:
3128 return L2CAP_MODE_BASIC;
3129 }
3130 }
3131
3132 static inline bool __l2cap_ews_supported(struct l2cap_conn *conn)
3133 {
3134 return ((conn->local_fixed_chan & L2CAP_FC_A2MP) &&
3135 (conn->feat_mask & L2CAP_FEAT_EXT_WINDOW));
3136 }
3137
3138 static inline bool __l2cap_efs_supported(struct l2cap_conn *conn)
3139 {
3140 return ((conn->local_fixed_chan & L2CAP_FC_A2MP) &&
3141 (conn->feat_mask & L2CAP_FEAT_EXT_FLOW));
3142 }
3143
3144 static void __l2cap_set_ertm_timeouts(struct l2cap_chan *chan,
3145 struct l2cap_conf_rfc *rfc)
3146 {
3147 if (chan->local_amp_id != AMP_ID_BREDR && chan->hs_hcon) {
3148 u64 ertm_to = chan->hs_hcon->hdev->amp_be_flush_to;
3149
3150 /* Class 1 devices have must have ERTM timeouts
3151 * exceeding the Link Supervision Timeout. The
3152 * default Link Supervision Timeout for AMP
3153 * controllers is 10 seconds.
3154 *
3155 * Class 1 devices use 0xffffffff for their
3156 * best-effort flush timeout, so the clamping logic
3157 * will result in a timeout that meets the above
3158 * requirement. ERTM timeouts are 16-bit values, so
3159 * the maximum timeout is 65.535 seconds.
3160 */
3161
3162 /* Convert timeout to milliseconds and round */
3163 ertm_to = DIV_ROUND_UP_ULL(ertm_to, 1000);
3164
3165 /* This is the recommended formula for class 2 devices
3166 * that start ERTM timers when packets are sent to the
3167 * controller.
3168 */
3169 ertm_to = 3 * ertm_to + 500;
3170
3171 if (ertm_to > 0xffff)
3172 ertm_to = 0xffff;
3173
3174 rfc->retrans_timeout = cpu_to_le16((u16) ertm_to);
3175 rfc->monitor_timeout = rfc->retrans_timeout;
3176 } else {
3177 rfc->retrans_timeout = cpu_to_le16(L2CAP_DEFAULT_RETRANS_TO);
3178 rfc->monitor_timeout = cpu_to_le16(L2CAP_DEFAULT_MONITOR_TO);
3179 }
3180 }
3181
3182 static inline void l2cap_txwin_setup(struct l2cap_chan *chan)
3183 {
3184 if (chan->tx_win > L2CAP_DEFAULT_TX_WINDOW &&
3185 __l2cap_ews_supported(chan->conn)) {
3186 /* use extended control field */
3187 set_bit(FLAG_EXT_CTRL, &chan->flags);
3188 chan->tx_win_max = L2CAP_DEFAULT_EXT_WINDOW;
3189 } else {
3190 chan->tx_win = min_t(u16, chan->tx_win,
3191 L2CAP_DEFAULT_TX_WINDOW);
3192 chan->tx_win_max = L2CAP_DEFAULT_TX_WINDOW;
3193 }
3194 chan->ack_win = chan->tx_win;
3195 }
3196
3197 static int l2cap_build_conf_req(struct l2cap_chan *chan, void *data, size_t data_size)
3198 {
3199 struct l2cap_conf_req *req = data;
3200 struct l2cap_conf_rfc rfc = { .mode = chan->mode };
3201 void *ptr = req->data;
3202 void *endptr = data + data_size;
3203 u16 size;
3204
3205 BT_DBG("chan %p", chan);
3206
3207 if (chan->num_conf_req || chan->num_conf_rsp)
3208 goto done;
3209
3210 switch (chan->mode) {
3211 case L2CAP_MODE_STREAMING:
3212 case L2CAP_MODE_ERTM:
3213 if (test_bit(CONF_STATE2_DEVICE, &chan->conf_state))
3214 break;
3215
3216 if (__l2cap_efs_supported(chan->conn))
3217 set_bit(FLAG_EFS_ENABLE, &chan->flags);
3218
3219 /* fall through */
3220 default:
3221 chan->mode = l2cap_select_mode(rfc.mode, chan->conn->feat_mask);
3222 break;
3223 }
3224
3225 done:
3226 if (chan->imtu != L2CAP_DEFAULT_MTU)
3227 l2cap_add_conf_opt(&ptr, L2CAP_CONF_MTU, 2, chan->imtu, endptr - ptr);
3228
3229 switch (chan->mode) {
3230 case L2CAP_MODE_BASIC:
3231 if (disable_ertm)
3232 break;
3233
3234 if (!(chan->conn->feat_mask & L2CAP_FEAT_ERTM) &&
3235 !(chan->conn->feat_mask & L2CAP_FEAT_STREAMING))
3236 break;
3237
3238 rfc.mode = L2CAP_MODE_BASIC;
3239 rfc.txwin_size = 0;
3240 rfc.max_transmit = 0;
3241 rfc.retrans_timeout = 0;
3242 rfc.monitor_timeout = 0;
3243 rfc.max_pdu_size = 0;
3244
3245 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3246 (unsigned long) &rfc, endptr - ptr);
3247 break;
3248
3249 case L2CAP_MODE_ERTM:
3250 rfc.mode = L2CAP_MODE_ERTM;
3251 rfc.max_transmit = chan->max_tx;
3252
3253 __l2cap_set_ertm_timeouts(chan, &rfc);
3254
3255 size = min_t(u16, L2CAP_DEFAULT_MAX_PDU_SIZE, chan->conn->mtu -
3256 L2CAP_EXT_HDR_SIZE - L2CAP_SDULEN_SIZE -
3257 L2CAP_FCS_SIZE);
3258 rfc.max_pdu_size = cpu_to_le16(size);
3259
3260 l2cap_txwin_setup(chan);
3261
3262 rfc.txwin_size = min_t(u16, chan->tx_win,
3263 L2CAP_DEFAULT_TX_WINDOW);
3264
3265 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3266 (unsigned long) &rfc, endptr - ptr);
3267
3268 if (test_bit(FLAG_EFS_ENABLE, &chan->flags))
3269 l2cap_add_opt_efs(&ptr, chan, endptr - ptr);
3270
3271 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
3272 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EWS, 2,
3273 chan->tx_win, endptr - ptr);
3274
3275 if (chan->conn->feat_mask & L2CAP_FEAT_FCS)
3276 if (chan->fcs == L2CAP_FCS_NONE ||
3277 test_bit(CONF_RECV_NO_FCS, &chan->conf_state)) {
3278 chan->fcs = L2CAP_FCS_NONE;
3279 l2cap_add_conf_opt(&ptr, L2CAP_CONF_FCS, 1,
3280 chan->fcs, endptr - ptr);
3281 }
3282 break;
3283
3284 case L2CAP_MODE_STREAMING:
3285 l2cap_txwin_setup(chan);
3286 rfc.mode = L2CAP_MODE_STREAMING;
3287 rfc.txwin_size = 0;
3288 rfc.max_transmit = 0;
3289 rfc.retrans_timeout = 0;
3290 rfc.monitor_timeout = 0;
3291
3292 size = min_t(u16, L2CAP_DEFAULT_MAX_PDU_SIZE, chan->conn->mtu -
3293 L2CAP_EXT_HDR_SIZE - L2CAP_SDULEN_SIZE -
3294 L2CAP_FCS_SIZE);
3295 rfc.max_pdu_size = cpu_to_le16(size);
3296
3297 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3298 (unsigned long) &rfc, endptr - ptr);
3299
3300 if (test_bit(FLAG_EFS_ENABLE, &chan->flags))
3301 l2cap_add_opt_efs(&ptr, chan, endptr - ptr);
3302
3303 if (chan->conn->feat_mask & L2CAP_FEAT_FCS)
3304 if (chan->fcs == L2CAP_FCS_NONE ||
3305 test_bit(CONF_RECV_NO_FCS, &chan->conf_state)) {
3306 chan->fcs = L2CAP_FCS_NONE;
3307 l2cap_add_conf_opt(&ptr, L2CAP_CONF_FCS, 1,
3308 chan->fcs, endptr - ptr);
3309 }
3310 break;
3311 }
3312
3313 req->dcid = cpu_to_le16(chan->dcid);
3314 req->flags = cpu_to_le16(0);
3315
3316 return ptr - data;
3317 }
3318
3319 static int l2cap_parse_conf_req(struct l2cap_chan *chan, void *data, size_t data_size)
3320 {
3321 struct l2cap_conf_rsp *rsp = data;
3322 void *ptr = rsp->data;
3323 void *endptr = data + data_size;
3324 void *req = chan->conf_req;
3325 int len = chan->conf_len;
3326 int type, hint, olen;
3327 unsigned long val;
3328 struct l2cap_conf_rfc rfc = { .mode = L2CAP_MODE_BASIC };
3329 struct l2cap_conf_efs efs;
3330 u8 remote_efs = 0;
3331 u16 mtu = L2CAP_DEFAULT_MTU;
3332 u16 result = L2CAP_CONF_SUCCESS;
3333 u16 size;
3334
3335 BT_DBG("chan %p", chan);
3336
3337 while (len >= L2CAP_CONF_OPT_SIZE) {
3338 len -= l2cap_get_conf_opt(&req, &type, &olen, &val);
3339
3340 hint = type & L2CAP_CONF_HINT;
3341 type &= L2CAP_CONF_MASK;
3342
3343 switch (type) {
3344 case L2CAP_CONF_MTU:
3345 mtu = val;
3346 break;
3347
3348 case L2CAP_CONF_FLUSH_TO:
3349 chan->flush_to = val;
3350 break;
3351
3352 case L2CAP_CONF_QOS:
3353 break;
3354
3355 case L2CAP_CONF_RFC:
3356 if (olen == sizeof(rfc))
3357 memcpy(&rfc, (void *) val, olen);
3358 break;
3359
3360 case L2CAP_CONF_FCS:
3361 if (val == L2CAP_FCS_NONE)
3362 set_bit(CONF_RECV_NO_FCS, &chan->conf_state);
3363 break;
3364
3365 case L2CAP_CONF_EFS:
3366 remote_efs = 1;
3367 if (olen == sizeof(efs))
3368 memcpy(&efs, (void *) val, olen);
3369 break;
3370
3371 case L2CAP_CONF_EWS:
3372 if (!(chan->conn->local_fixed_chan & L2CAP_FC_A2MP))
3373 return -ECONNREFUSED;
3374
3375 set_bit(FLAG_EXT_CTRL, &chan->flags);
3376 set_bit(CONF_EWS_RECV, &chan->conf_state);
3377 chan->tx_win_max = L2CAP_DEFAULT_EXT_WINDOW;
3378 chan->remote_tx_win = val;
3379 break;
3380
3381 default:
3382 if (hint)
3383 break;
3384
3385 result = L2CAP_CONF_UNKNOWN;
3386 *((u8 *) ptr++) = type;
3387 break;
3388 }
3389 }
3390
3391 if (chan->num_conf_rsp || chan->num_conf_req > 1)
3392 goto done;
3393
3394 switch (chan->mode) {
3395 case L2CAP_MODE_STREAMING:
3396 case L2CAP_MODE_ERTM:
3397 if (!test_bit(CONF_STATE2_DEVICE, &chan->conf_state)) {
3398 chan->mode = l2cap_select_mode(rfc.mode,
3399 chan->conn->feat_mask);
3400 break;
3401 }
3402
3403 if (remote_efs) {
3404 if (__l2cap_efs_supported(chan->conn))
3405 set_bit(FLAG_EFS_ENABLE, &chan->flags);
3406 else
3407 return -ECONNREFUSED;
3408 }
3409
3410 if (chan->mode != rfc.mode)
3411 return -ECONNREFUSED;
3412
3413 break;
3414 }
3415
3416 done:
3417 if (chan->mode != rfc.mode) {
3418 result = L2CAP_CONF_UNACCEPT;
3419 rfc.mode = chan->mode;
3420
3421 if (chan->num_conf_rsp == 1)
3422 return -ECONNREFUSED;
3423
3424 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3425 (unsigned long) &rfc, endptr - ptr);
3426 }
3427
3428 if (result == L2CAP_CONF_SUCCESS) {
3429 /* Configure output options and let the other side know
3430 * which ones we don't like. */
3431
3432 if (mtu < L2CAP_DEFAULT_MIN_MTU)
3433 result = L2CAP_CONF_UNACCEPT;
3434 else {
3435 chan->omtu = mtu;
3436 set_bit(CONF_MTU_DONE, &chan->conf_state);
3437 }
3438 l2cap_add_conf_opt(&ptr, L2CAP_CONF_MTU, 2, chan->omtu, endptr - ptr);
3439
3440 if (remote_efs) {
3441 if (chan->local_stype != L2CAP_SERV_NOTRAFIC &&
3442 efs.stype != L2CAP_SERV_NOTRAFIC &&
3443 efs.stype != chan->local_stype) {
3444
3445 result = L2CAP_CONF_UNACCEPT;
3446
3447 if (chan->num_conf_req >= 1)
3448 return -ECONNREFUSED;
3449
3450 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EFS,
3451 sizeof(efs),
3452 (unsigned long) &efs, endptr - ptr);
3453 } else {
3454 /* Send PENDING Conf Rsp */
3455 result = L2CAP_CONF_PENDING;
3456 set_bit(CONF_LOC_CONF_PEND, &chan->conf_state);
3457 }
3458 }
3459
3460 switch (rfc.mode) {
3461 case L2CAP_MODE_BASIC:
3462 chan->fcs = L2CAP_FCS_NONE;
3463 set_bit(CONF_MODE_DONE, &chan->conf_state);
3464 break;
3465
3466 case L2CAP_MODE_ERTM:
3467 if (!test_bit(CONF_EWS_RECV, &chan->conf_state))
3468 chan->remote_tx_win = rfc.txwin_size;
3469 else
3470 rfc.txwin_size = L2CAP_DEFAULT_TX_WINDOW;
3471
3472 chan->remote_max_tx = rfc.max_transmit;
3473
3474 size = min_t(u16, le16_to_cpu(rfc.max_pdu_size),
3475 chan->conn->mtu - L2CAP_EXT_HDR_SIZE -
3476 L2CAP_SDULEN_SIZE - L2CAP_FCS_SIZE);
3477 rfc.max_pdu_size = cpu_to_le16(size);
3478 chan->remote_mps = size;
3479
3480 __l2cap_set_ertm_timeouts(chan, &rfc);
3481
3482 set_bit(CONF_MODE_DONE, &chan->conf_state);
3483
3484 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC,
3485 sizeof(rfc), (unsigned long) &rfc, endptr - ptr);
3486
3487 if (test_bit(FLAG_EFS_ENABLE, &chan->flags)) {
3488 chan->remote_id = efs.id;
3489 chan->remote_stype = efs.stype;
3490 chan->remote_msdu = le16_to_cpu(efs.msdu);
3491 chan->remote_flush_to =
3492 le32_to_cpu(efs.flush_to);
3493 chan->remote_acc_lat =
3494 le32_to_cpu(efs.acc_lat);
3495 chan->remote_sdu_itime =
3496 le32_to_cpu(efs.sdu_itime);
3497 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EFS,
3498 sizeof(efs),
3499 (unsigned long) &efs, endptr - ptr);
3500 }
3501 break;
3502
3503 case L2CAP_MODE_STREAMING:
3504 size = min_t(u16, le16_to_cpu(rfc.max_pdu_size),
3505 chan->conn->mtu - L2CAP_EXT_HDR_SIZE -
3506 L2CAP_SDULEN_SIZE - L2CAP_FCS_SIZE);
3507 rfc.max_pdu_size = cpu_to_le16(size);
3508 chan->remote_mps = size;
3509
3510 set_bit(CONF_MODE_DONE, &chan->conf_state);
3511
3512 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
3513 (unsigned long) &rfc, endptr - ptr);
3514
3515 break;
3516
3517 default:
3518 result = L2CAP_CONF_UNACCEPT;
3519
3520 memset(&rfc, 0, sizeof(rfc));
3521 rfc.mode = chan->mode;
3522 }
3523
3524 if (result == L2CAP_CONF_SUCCESS)
3525 set_bit(CONF_OUTPUT_DONE, &chan->conf_state);
3526 }
3527 rsp->scid = cpu_to_le16(chan->dcid);
3528 rsp->result = cpu_to_le16(result);
3529 rsp->flags = cpu_to_le16(0);
3530
3531 return ptr - data;
3532 }
3533
3534 static int l2cap_parse_conf_rsp(struct l2cap_chan *chan, void *rsp, int len,
3535 void *data, size_t size, u16 *result)
3536 {
3537 struct l2cap_conf_req *req = data;
3538 void *ptr = req->data;
3539 void *endptr = data + size;
3540 int type, olen;
3541 unsigned long val;
3542 struct l2cap_conf_rfc rfc = { .mode = L2CAP_MODE_BASIC };
3543 struct l2cap_conf_efs efs;
3544
3545 BT_DBG("chan %p, rsp %p, len %d, req %p", chan, rsp, len, data);
3546
3547 while (len >= L2CAP_CONF_OPT_SIZE) {
3548 len -= l2cap_get_conf_opt(&rsp, &type, &olen, &val);
3549
3550 switch (type) {
3551 case L2CAP_CONF_MTU:
3552 if (val < L2CAP_DEFAULT_MIN_MTU) {
3553 *result = L2CAP_CONF_UNACCEPT;
3554 chan->imtu = L2CAP_DEFAULT_MIN_MTU;
3555 } else
3556 chan->imtu = val;
3557 l2cap_add_conf_opt(&ptr, L2CAP_CONF_MTU, 2, chan->imtu, endptr - ptr);
3558 break;
3559
3560 case L2CAP_CONF_FLUSH_TO:
3561 chan->flush_to = val;
3562 l2cap_add_conf_opt(&ptr, L2CAP_CONF_FLUSH_TO,
3563 2, chan->flush_to, endptr - ptr);
3564 break;
3565
3566 case L2CAP_CONF_RFC:
3567 if (olen == sizeof(rfc))
3568 memcpy(&rfc, (void *)val, olen);
3569
3570 if (test_bit(CONF_STATE2_DEVICE, &chan->conf_state) &&
3571 rfc.mode != chan->mode)
3572 return -ECONNREFUSED;
3573
3574 chan->fcs = 0;
3575
3576 l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC,
3577 sizeof(rfc), (unsigned long) &rfc, endptr - ptr);
3578 break;
3579
3580 case L2CAP_CONF_EWS:
3581 chan->ack_win = min_t(u16, val, chan->ack_win);
3582 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EWS, 2,
3583 chan->tx_win, endptr - ptr);
3584 break;
3585
3586 case L2CAP_CONF_EFS:
3587 if (olen == sizeof(efs))
3588 memcpy(&efs, (void *)val, olen);
3589
3590 if (chan->local_stype != L2CAP_SERV_NOTRAFIC &&
3591 efs.stype != L2CAP_SERV_NOTRAFIC &&
3592 efs.stype != chan->local_stype)
3593 return -ECONNREFUSED;
3594
3595 l2cap_add_conf_opt(&ptr, L2CAP_CONF_EFS, sizeof(efs),
3596 (unsigned long) &efs, endptr - ptr);
3597 break;
3598
3599 case L2CAP_CONF_FCS:
3600 if (*result == L2CAP_CONF_PENDING)
3601 if (val == L2CAP_FCS_NONE)
3602 set_bit(CONF_RECV_NO_FCS,
3603 &chan->conf_state);
3604 break;
3605 }
3606 }
3607
3608 if (chan->mode == L2CAP_MODE_BASIC && chan->mode != rfc.mode)
3609 return -ECONNREFUSED;
3610
3611 chan->mode = rfc.mode;
3612
3613 if (*result == L2CAP_CONF_SUCCESS || *result == L2CAP_CONF_PENDING) {
3614 switch (rfc.mode) {
3615 case L2CAP_MODE_ERTM:
3616 chan->retrans_timeout = le16_to_cpu(rfc.retrans_timeout);
3617 chan->monitor_timeout = le16_to_cpu(rfc.monitor_timeout);
3618 chan->mps = le16_to_cpu(rfc.max_pdu_size);
3619 if (!test_bit(FLAG_EXT_CTRL, &chan->flags))
3620 chan->ack_win = min_t(u16, chan->ack_win,
3621 rfc.txwin_size);
3622
3623 if (test_bit(FLAG_EFS_ENABLE, &chan->flags)) {
3624 chan->local_msdu = le16_to_cpu(efs.msdu);
3625 chan->local_sdu_itime =
3626 le32_to_cpu(efs.sdu_itime);
3627 chan->local_acc_lat = le32_to_cpu(efs.acc_lat);
3628 chan->local_flush_to =
3629 le32_to_cpu(efs.flush_to);
3630 }
3631 break;
3632
3633 case L2CAP_MODE_STREAMING:
3634 chan->mps = le16_to_cpu(rfc.max_pdu_size);
3635 }
3636 }
3637
3638 req->dcid = cpu_to_le16(chan->dcid);
3639 req->flags = cpu_to_le16(0);
3640
3641 return ptr - data;
3642 }
3643
3644 static int l2cap_build_conf_rsp(struct l2cap_chan *chan, void *data,
3645 u16 result, u16 flags)
3646 {
3647 struct l2cap_conf_rsp *rsp = data;
3648 void *ptr = rsp->data;
3649
3650 BT_DBG("chan %p", chan);
3651
3652 rsp->scid = cpu_to_le16(chan->dcid);
3653 rsp->result = cpu_to_le16(result);
3654 rsp->flags = cpu_to_le16(flags);
3655
3656 return ptr - data;
3657 }
3658
3659 void __l2cap_le_connect_rsp_defer(struct l2cap_chan *chan)
3660 {
3661 struct l2cap_le_conn_rsp rsp;
3662 struct l2cap_conn *conn = chan->conn;
3663
3664 BT_DBG("chan %p", chan);
3665
3666 rsp.dcid = cpu_to_le16(chan->scid);
3667 rsp.mtu = cpu_to_le16(chan->imtu);
3668 rsp.mps = cpu_to_le16(chan->mps);
3669 rsp.credits = cpu_to_le16(chan->rx_credits);
3670 rsp.result = cpu_to_le16(L2CAP_CR_SUCCESS);
3671
3672 l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CONN_RSP, sizeof(rsp),
3673 &rsp);
3674 }
3675
3676 void __l2cap_connect_rsp_defer(struct l2cap_chan *chan)
3677 {
3678 struct l2cap_conn_rsp rsp;
3679 struct l2cap_conn *conn = chan->conn;
3680 u8 buf[128];
3681 u8 rsp_code;
3682
3683 rsp.scid = cpu_to_le16(chan->dcid);
3684 rsp.dcid = cpu_to_le16(chan->scid);
3685 rsp.result = cpu_to_le16(L2CAP_CR_SUCCESS);
3686 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
3687
3688 if (chan->hs_hcon)
3689 rsp_code = L2CAP_CREATE_CHAN_RSP;
3690 else
3691 rsp_code = L2CAP_CONN_RSP;
3692
3693 BT_DBG("chan %p rsp_code %u", chan, rsp_code);
3694
3695 l2cap_send_cmd(conn, chan->ident, rsp_code, sizeof(rsp), &rsp);
3696
3697 if (test_and_set_bit(CONF_REQ_SENT, &chan->conf_state))
3698 return;
3699
3700 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
3701 l2cap_build_conf_req(chan, buf, sizeof(buf)), buf);
3702 chan->num_conf_req++;
3703 }
3704
3705 static void l2cap_conf_rfc_get(struct l2cap_chan *chan, void *rsp, int len)
3706 {
3707 int type, olen;
3708 unsigned long val;
3709 /* Use sane default values in case a misbehaving remote device
3710 * did not send an RFC or extended window size option.
3711 */
3712 u16 txwin_ext = chan->ack_win;
3713 struct l2cap_conf_rfc rfc = {
3714 .mode = chan->mode,
3715 .retrans_timeout = cpu_to_le16(L2CAP_DEFAULT_RETRANS_TO),
3716 .monitor_timeout = cpu_to_le16(L2CAP_DEFAULT_MONITOR_TO),
3717 .max_pdu_size = cpu_to_le16(chan->imtu),
3718 .txwin_size = min_t(u16, chan->ack_win, L2CAP_DEFAULT_TX_WINDOW),
3719 };
3720
3721 BT_DBG("chan %p, rsp %p, len %d", chan, rsp, len);
3722
3723 if ((chan->mode != L2CAP_MODE_ERTM) && (chan->mode != L2CAP_MODE_STREAMING))
3724 return;
3725
3726 while (len >= L2CAP_CONF_OPT_SIZE) {
3727 len -= l2cap_get_conf_opt(&rsp, &type, &olen, &val);
3728
3729 switch (type) {
3730 case L2CAP_CONF_RFC:
3731 if (olen == sizeof(rfc))
3732 memcpy(&rfc, (void *)val, olen);
3733 break;
3734 case L2CAP_CONF_EWS:
3735 txwin_ext = val;
3736 break;
3737 }
3738 }
3739
3740 switch (rfc.mode) {
3741 case L2CAP_MODE_ERTM:
3742 chan->retrans_timeout = le16_to_cpu(rfc.retrans_timeout);
3743 chan->monitor_timeout = le16_to_cpu(rfc.monitor_timeout);
3744 chan->mps = le16_to_cpu(rfc.max_pdu_size);
3745 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
3746 chan->ack_win = min_t(u16, chan->ack_win, txwin_ext);
3747 else
3748 chan->ack_win = min_t(u16, chan->ack_win,
3749 rfc.txwin_size);
3750 break;
3751 case L2CAP_MODE_STREAMING:
3752 chan->mps = le16_to_cpu(rfc.max_pdu_size);
3753 }
3754 }
3755
3756 static inline int l2cap_command_rej(struct l2cap_conn *conn,
3757 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
3758 u8 *data)
3759 {
3760 struct l2cap_cmd_rej_unk *rej = (struct l2cap_cmd_rej_unk *) data;
3761
3762 if (cmd_len < sizeof(*rej))
3763 return -EPROTO;
3764
3765 if (rej->reason != L2CAP_REJ_NOT_UNDERSTOOD)
3766 return 0;
3767
3768 if ((conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT) &&
3769 cmd->ident == conn->info_ident) {
3770 cancel_delayed_work(&conn->info_timer);
3771
3772 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
3773 conn->info_ident = 0;
3774
3775 l2cap_conn_start(conn);
3776 }
3777
3778 return 0;
3779 }
3780
3781 static struct l2cap_chan *l2cap_connect(struct l2cap_conn *conn,
3782 struct l2cap_cmd_hdr *cmd,
3783 u8 *data, u8 rsp_code, u8 amp_id)
3784 {
3785 struct l2cap_conn_req *req = (struct l2cap_conn_req *) data;
3786 struct l2cap_conn_rsp rsp;
3787 struct l2cap_chan *chan = NULL, *pchan;
3788 int result, status = L2CAP_CS_NO_INFO;
3789
3790 u16 dcid = 0, scid = __le16_to_cpu(req->scid);
3791 __le16 psm = req->psm;
3792
3793 BT_DBG("psm 0x%2.2x scid 0x%4.4x", __le16_to_cpu(psm), scid);
3794
3795 /* Check if we have socket listening on psm */
3796 pchan = l2cap_global_chan_by_psm(BT_LISTEN, psm, &conn->hcon->src,
3797 &conn->hcon->dst, ACL_LINK);
3798 if (!pchan) {
3799 result = L2CAP_CR_BAD_PSM;
3800 goto sendresp;
3801 }
3802
3803 mutex_lock(&conn->chan_lock);
3804 l2cap_chan_lock(pchan);
3805
3806 /* Check if the ACL is secure enough (if not SDP) */
3807 if (psm != cpu_to_le16(L2CAP_PSM_SDP) &&
3808 !hci_conn_check_link_mode(conn->hcon)) {
3809 conn->disc_reason = HCI_ERROR_AUTH_FAILURE;
3810 result = L2CAP_CR_SEC_BLOCK;
3811 goto response;
3812 }
3813
3814 result = L2CAP_CR_NO_MEM;
3815
3816 /* Check if we already have channel with that dcid */
3817 if (__l2cap_get_chan_by_dcid(conn, scid))
3818 goto response;
3819
3820 chan = pchan->ops->new_connection(pchan);
3821 if (!chan)
3822 goto response;
3823
3824 /* For certain devices (ex: HID mouse), support for authentication,
3825 * pairing and bonding is optional. For such devices, inorder to avoid
3826 * the ACL alive for too long after L2CAP disconnection, reset the ACL
3827 * disc_timeout back to HCI_DISCONN_TIMEOUT during L2CAP connect.
3828 */
3829 conn->hcon->disc_timeout = HCI_DISCONN_TIMEOUT;
3830
3831 bacpy(&chan->src, &conn->hcon->src);
3832 bacpy(&chan->dst, &conn->hcon->dst);
3833 chan->src_type = bdaddr_src_type(conn->hcon);
3834 chan->dst_type = bdaddr_dst_type(conn->hcon);
3835 chan->psm = psm;
3836 chan->dcid = scid;
3837 chan->local_amp_id = amp_id;
3838
3839 __l2cap_chan_add(conn, chan);
3840
3841 dcid = chan->scid;
3842
3843 __set_chan_timer(chan, chan->ops->get_sndtimeo(chan));
3844
3845 chan->ident = cmd->ident;
3846
3847 if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE) {
3848 if (l2cap_chan_check_security(chan, false)) {
3849 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) {
3850 l2cap_state_change(chan, BT_CONNECT2);
3851 result = L2CAP_CR_PEND;
3852 status = L2CAP_CS_AUTHOR_PEND;
3853 chan->ops->defer(chan);
3854 } else {
3855 /* Force pending result for AMP controllers.
3856 * The connection will succeed after the
3857 * physical link is up.
3858 */
3859 if (amp_id == AMP_ID_BREDR) {
3860 l2cap_state_change(chan, BT_CONFIG);
3861 result = L2CAP_CR_SUCCESS;
3862 } else {
3863 l2cap_state_change(chan, BT_CONNECT2);
3864 result = L2CAP_CR_PEND;
3865 }
3866 status = L2CAP_CS_NO_INFO;
3867 }
3868 } else {
3869 l2cap_state_change(chan, BT_CONNECT2);
3870 result = L2CAP_CR_PEND;
3871 status = L2CAP_CS_AUTHEN_PEND;
3872 }
3873 } else {
3874 l2cap_state_change(chan, BT_CONNECT2);
3875 result = L2CAP_CR_PEND;
3876 status = L2CAP_CS_NO_INFO;
3877 }
3878
3879 response:
3880 l2cap_chan_unlock(pchan);
3881 mutex_unlock(&conn->chan_lock);
3882 l2cap_chan_put(pchan);
3883
3884 sendresp:
3885 rsp.scid = cpu_to_le16(scid);
3886 rsp.dcid = cpu_to_le16(dcid);
3887 rsp.result = cpu_to_le16(result);
3888 rsp.status = cpu_to_le16(status);
3889 l2cap_send_cmd(conn, cmd->ident, rsp_code, sizeof(rsp), &rsp);
3890
3891 if (result == L2CAP_CR_PEND && status == L2CAP_CS_NO_INFO) {
3892 struct l2cap_info_req info;
3893 info.type = cpu_to_le16(L2CAP_IT_FEAT_MASK);
3894
3895 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_SENT;
3896 conn->info_ident = l2cap_get_ident(conn);
3897
3898 schedule_delayed_work(&conn->info_timer, L2CAP_INFO_TIMEOUT);
3899
3900 l2cap_send_cmd(conn, conn->info_ident, L2CAP_INFO_REQ,
3901 sizeof(info), &info);
3902 }
3903
3904 if (chan && !test_bit(CONF_REQ_SENT, &chan->conf_state) &&
3905 result == L2CAP_CR_SUCCESS) {
3906 u8 buf[128];
3907 set_bit(CONF_REQ_SENT, &chan->conf_state);
3908 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
3909 l2cap_build_conf_req(chan, buf, sizeof(buf)), buf);
3910 chan->num_conf_req++;
3911 }
3912
3913 return chan;
3914 }
3915
3916 static int l2cap_connect_req(struct l2cap_conn *conn,
3917 struct l2cap_cmd_hdr *cmd, u16 cmd_len, u8 *data)
3918 {
3919 struct hci_dev *hdev = conn->hcon->hdev;
3920 struct hci_conn *hcon = conn->hcon;
3921
3922 if (cmd_len < sizeof(struct l2cap_conn_req))
3923 return -EPROTO;
3924
3925 hci_dev_lock(hdev);
3926 if (hci_dev_test_flag(hdev, HCI_MGMT) &&
3927 !test_and_set_bit(HCI_CONN_MGMT_CONNECTED, &hcon->flags))
3928 mgmt_device_connected(hdev, hcon, 0, NULL, 0);
3929 hci_dev_unlock(hdev);
3930
3931 l2cap_connect(conn, cmd, data, L2CAP_CONN_RSP, 0);
3932 return 0;
3933 }
3934
3935 static int l2cap_connect_create_rsp(struct l2cap_conn *conn,
3936 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
3937 u8 *data)
3938 {
3939 struct l2cap_conn_rsp *rsp = (struct l2cap_conn_rsp *) data;
3940 u16 scid, dcid, result, status;
3941 struct l2cap_chan *chan;
3942 u8 req[128];
3943 int err;
3944
3945 if (cmd_len < sizeof(*rsp))
3946 return -EPROTO;
3947
3948 scid = __le16_to_cpu(rsp->scid);
3949 dcid = __le16_to_cpu(rsp->dcid);
3950 result = __le16_to_cpu(rsp->result);
3951 status = __le16_to_cpu(rsp->status);
3952
3953 BT_DBG("dcid 0x%4.4x scid 0x%4.4x result 0x%2.2x status 0x%2.2x",
3954 dcid, scid, result, status);
3955
3956 mutex_lock(&conn->chan_lock);
3957
3958 if (scid) {
3959 chan = __l2cap_get_chan_by_scid(conn, scid);
3960 if (!chan) {
3961 err = -EBADSLT;
3962 goto unlock;
3963 }
3964 } else {
3965 chan = __l2cap_get_chan_by_ident(conn, cmd->ident);
3966 if (!chan) {
3967 err = -EBADSLT;
3968 goto unlock;
3969 }
3970 }
3971
3972 err = 0;
3973
3974 l2cap_chan_lock(chan);
3975
3976 switch (result) {
3977 case L2CAP_CR_SUCCESS:
3978 l2cap_state_change(chan, BT_CONFIG);
3979 chan->ident = 0;
3980 chan->dcid = dcid;
3981 clear_bit(CONF_CONNECT_PEND, &chan->conf_state);
3982
3983 if (test_and_set_bit(CONF_REQ_SENT, &chan->conf_state))
3984 break;
3985
3986 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
3987 l2cap_build_conf_req(chan, req, sizeof(req)), req);
3988 chan->num_conf_req++;
3989 break;
3990
3991 case L2CAP_CR_PEND:
3992 set_bit(CONF_CONNECT_PEND, &chan->conf_state);
3993 break;
3994
3995 default:
3996 l2cap_chan_del(chan, ECONNREFUSED);
3997 break;
3998 }
3999
4000 l2cap_chan_unlock(chan);
4001
4002 unlock:
4003 mutex_unlock(&conn->chan_lock);
4004
4005 return err;
4006 }
4007
4008 static inline void set_default_fcs(struct l2cap_chan *chan)
4009 {
4010 /* FCS is enabled only in ERTM or streaming mode, if one or both
4011 * sides request it.
4012 */
4013 if (chan->mode != L2CAP_MODE_ERTM && chan->mode != L2CAP_MODE_STREAMING)
4014 chan->fcs = L2CAP_FCS_NONE;
4015 else if (!test_bit(CONF_RECV_NO_FCS, &chan->conf_state))
4016 chan->fcs = L2CAP_FCS_CRC16;
4017 }
4018
4019 static void l2cap_send_efs_conf_rsp(struct l2cap_chan *chan, void *data,
4020 u8 ident, u16 flags)
4021 {
4022 struct l2cap_conn *conn = chan->conn;
4023
4024 BT_DBG("conn %p chan %p ident %d flags 0x%4.4x", conn, chan, ident,
4025 flags);
4026
4027 clear_bit(CONF_LOC_CONF_PEND, &chan->conf_state);
4028 set_bit(CONF_OUTPUT_DONE, &chan->conf_state);
4029
4030 l2cap_send_cmd(conn, ident, L2CAP_CONF_RSP,
4031 l2cap_build_conf_rsp(chan, data,
4032 L2CAP_CONF_SUCCESS, flags), data);
4033 }
4034
4035 static void cmd_reject_invalid_cid(struct l2cap_conn *conn, u8 ident,
4036 u16 scid, u16 dcid)
4037 {
4038 struct l2cap_cmd_rej_cid rej;
4039
4040 rej.reason = cpu_to_le16(L2CAP_REJ_INVALID_CID);
4041 rej.scid = __cpu_to_le16(scid);
4042 rej.dcid = __cpu_to_le16(dcid);
4043
4044 l2cap_send_cmd(conn, ident, L2CAP_COMMAND_REJ, sizeof(rej), &rej);
4045 }
4046
4047 static inline int l2cap_config_req(struct l2cap_conn *conn,
4048 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4049 u8 *data)
4050 {
4051 struct l2cap_conf_req *req = (struct l2cap_conf_req *) data;
4052 u16 dcid, flags;
4053 u8 rsp[64];
4054 struct l2cap_chan *chan;
4055 int len, err = 0;
4056
4057 if (cmd_len < sizeof(*req))
4058 return -EPROTO;
4059
4060 dcid = __le16_to_cpu(req->dcid);
4061 flags = __le16_to_cpu(req->flags);
4062
4063 BT_DBG("dcid 0x%4.4x flags 0x%2.2x", dcid, flags);
4064
4065 chan = l2cap_get_chan_by_scid(conn, dcid);
4066 if (!chan) {
4067 cmd_reject_invalid_cid(conn, cmd->ident, dcid, 0);
4068 return 0;
4069 }
4070
4071 if (chan->state != BT_CONFIG && chan->state != BT_CONNECT2) {
4072 cmd_reject_invalid_cid(conn, cmd->ident, chan->scid,
4073 chan->dcid);
4074 goto unlock;
4075 }
4076
4077 /* Reject if config buffer is too small. */
4078 len = cmd_len - sizeof(*req);
4079 if (chan->conf_len + len > sizeof(chan->conf_req)) {
4080 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP,
4081 l2cap_build_conf_rsp(chan, rsp,
4082 L2CAP_CONF_REJECT, flags), rsp);
4083 goto unlock;
4084 }
4085
4086 /* Store config. */
4087 memcpy(chan->conf_req + chan->conf_len, req->data, len);
4088 chan->conf_len += len;
4089
4090 if (flags & L2CAP_CONF_FLAG_CONTINUATION) {
4091 /* Incomplete config. Send empty response. */
4092 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP,
4093 l2cap_build_conf_rsp(chan, rsp,
4094 L2CAP_CONF_SUCCESS, flags), rsp);
4095 goto unlock;
4096 }
4097
4098 /* Complete config. */
4099 len = l2cap_parse_conf_req(chan, rsp, sizeof(rsp));
4100 if (len < 0) {
4101 l2cap_send_disconn_req(chan, ECONNRESET);
4102 goto unlock;
4103 }
4104
4105 chan->ident = cmd->ident;
4106 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP, len, rsp);
4107 chan->num_conf_rsp++;
4108
4109 /* Reset config buffer. */
4110 chan->conf_len = 0;
4111
4112 if (!test_bit(CONF_OUTPUT_DONE, &chan->conf_state))
4113 goto unlock;
4114
4115 if (test_bit(CONF_INPUT_DONE, &chan->conf_state)) {
4116 set_default_fcs(chan);
4117
4118 if (chan->mode == L2CAP_MODE_ERTM ||
4119 chan->mode == L2CAP_MODE_STREAMING)
4120 err = l2cap_ertm_init(chan);
4121
4122 if (err < 0)
4123 l2cap_send_disconn_req(chan, -err);
4124 else
4125 l2cap_chan_ready(chan);
4126
4127 goto unlock;
4128 }
4129
4130 if (!test_and_set_bit(CONF_REQ_SENT, &chan->conf_state)) {
4131 u8 buf[64];
4132 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ,
4133 l2cap_build_conf_req(chan, buf, sizeof(buf)), buf);
4134 chan->num_conf_req++;
4135 }
4136
4137 /* Got Conf Rsp PENDING from remote side and assume we sent
4138 Conf Rsp PENDING in the code above */
4139 if (test_bit(CONF_REM_CONF_PEND, &chan->conf_state) &&
4140 test_bit(CONF_LOC_CONF_PEND, &chan->conf_state)) {
4141
4142 /* check compatibility */
4143
4144 /* Send rsp for BR/EDR channel */
4145 if (!chan->hs_hcon)
4146 l2cap_send_efs_conf_rsp(chan, rsp, cmd->ident, flags);
4147 else
4148 chan->ident = cmd->ident;
4149 }
4150
4151 unlock:
4152 l2cap_chan_unlock(chan);
4153 return err;
4154 }
4155
4156 static inline int l2cap_config_rsp(struct l2cap_conn *conn,
4157 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4158 u8 *data)
4159 {
4160 struct l2cap_conf_rsp *rsp = (struct l2cap_conf_rsp *)data;
4161 u16 scid, flags, result;
4162 struct l2cap_chan *chan;
4163 int len = cmd_len - sizeof(*rsp);
4164 int err = 0;
4165
4166 if (cmd_len < sizeof(*rsp))
4167 return -EPROTO;
4168
4169 scid = __le16_to_cpu(rsp->scid);
4170 flags = __le16_to_cpu(rsp->flags);
4171 result = __le16_to_cpu(rsp->result);
4172
4173 BT_DBG("scid 0x%4.4x flags 0x%2.2x result 0x%2.2x len %d", scid, flags,
4174 result, len);
4175
4176 chan = l2cap_get_chan_by_scid(conn, scid);
4177 if (!chan)
4178 return 0;
4179
4180 switch (result) {
4181 case L2CAP_CONF_SUCCESS:
4182 l2cap_conf_rfc_get(chan, rsp->data, len);
4183 clear_bit(CONF_REM_CONF_PEND, &chan->conf_state);
4184 break;
4185
4186 case L2CAP_CONF_PENDING:
4187 set_bit(CONF_REM_CONF_PEND, &chan->conf_state);
4188
4189 if (test_bit(CONF_LOC_CONF_PEND, &chan->conf_state)) {
4190 char buf[64];
4191
4192 len = l2cap_parse_conf_rsp(chan, rsp->data, len,
4193 buf, sizeof(buf), &result);
4194 if (len < 0) {
4195 l2cap_send_disconn_req(chan, ECONNRESET);
4196 goto done;
4197 }
4198
4199 if (!chan->hs_hcon) {
4200 l2cap_send_efs_conf_rsp(chan, buf, cmd->ident,
4201 0);
4202 } else {
4203 if (l2cap_check_efs(chan)) {
4204 amp_create_logical_link(chan);
4205 chan->ident = cmd->ident;
4206 }
4207 }
4208 }
4209 goto done;
4210
4211 case L2CAP_CONF_UNACCEPT:
4212 if (chan->num_conf_rsp <= L2CAP_CONF_MAX_CONF_RSP) {
4213 char req[64];
4214
4215 if (len > sizeof(req) - sizeof(struct l2cap_conf_req)) {
4216 l2cap_send_disconn_req(chan, ECONNRESET);
4217 goto done;
4218 }
4219
4220 /* throw out any old stored conf requests */
4221 result = L2CAP_CONF_SUCCESS;
4222 len = l2cap_parse_conf_rsp(chan, rsp->data, len,
4223 req, sizeof(req), &result);
4224 if (len < 0) {
4225 l2cap_send_disconn_req(chan, ECONNRESET);
4226 goto done;
4227 }
4228
4229 l2cap_send_cmd(conn, l2cap_get_ident(conn),
4230 L2CAP_CONF_REQ, len, req);
4231 chan->num_conf_req++;
4232 if (result != L2CAP_CONF_SUCCESS)
4233 goto done;
4234 break;
4235 }
4236
4237 default:
4238 l2cap_chan_set_err(chan, ECONNRESET);
4239
4240 __set_chan_timer(chan, L2CAP_DISC_REJ_TIMEOUT);
4241 l2cap_send_disconn_req(chan, ECONNRESET);
4242 goto done;
4243 }
4244
4245 if (flags & L2CAP_CONF_FLAG_CONTINUATION)
4246 goto done;
4247
4248 set_bit(CONF_INPUT_DONE, &chan->conf_state);
4249
4250 if (test_bit(CONF_OUTPUT_DONE, &chan->conf_state)) {
4251 set_default_fcs(chan);
4252
4253 if (chan->mode == L2CAP_MODE_ERTM ||
4254 chan->mode == L2CAP_MODE_STREAMING)
4255 err = l2cap_ertm_init(chan);
4256
4257 if (err < 0)
4258 l2cap_send_disconn_req(chan, -err);
4259 else
4260 l2cap_chan_ready(chan);
4261 }
4262
4263 done:
4264 l2cap_chan_unlock(chan);
4265 return err;
4266 }
4267
4268 static inline int l2cap_disconnect_req(struct l2cap_conn *conn,
4269 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4270 u8 *data)
4271 {
4272 struct l2cap_disconn_req *req = (struct l2cap_disconn_req *) data;
4273 struct l2cap_disconn_rsp rsp;
4274 u16 dcid, scid;
4275 struct l2cap_chan *chan;
4276
4277 if (cmd_len != sizeof(*req))
4278 return -EPROTO;
4279
4280 scid = __le16_to_cpu(req->scid);
4281 dcid = __le16_to_cpu(req->dcid);
4282
4283 BT_DBG("scid 0x%4.4x dcid 0x%4.4x", scid, dcid);
4284
4285 mutex_lock(&conn->chan_lock);
4286
4287 chan = __l2cap_get_chan_by_scid(conn, dcid);
4288 if (!chan) {
4289 mutex_unlock(&conn->chan_lock);
4290 cmd_reject_invalid_cid(conn, cmd->ident, dcid, scid);
4291 return 0;
4292 }
4293
4294 l2cap_chan_lock(chan);
4295
4296 rsp.dcid = cpu_to_le16(chan->scid);
4297 rsp.scid = cpu_to_le16(chan->dcid);
4298 l2cap_send_cmd(conn, cmd->ident, L2CAP_DISCONN_RSP, sizeof(rsp), &rsp);
4299
4300 chan->ops->set_shutdown(chan);
4301
4302 l2cap_chan_hold(chan);
4303 l2cap_chan_del(chan, ECONNRESET);
4304
4305 l2cap_chan_unlock(chan);
4306
4307 chan->ops->close(chan);
4308 l2cap_chan_put(chan);
4309
4310 mutex_unlock(&conn->chan_lock);
4311
4312 return 0;
4313 }
4314
4315 static inline int l2cap_disconnect_rsp(struct l2cap_conn *conn,
4316 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4317 u8 *data)
4318 {
4319 struct l2cap_disconn_rsp *rsp = (struct l2cap_disconn_rsp *) data;
4320 u16 dcid, scid;
4321 struct l2cap_chan *chan;
4322
4323 if (cmd_len != sizeof(*rsp))
4324 return -EPROTO;
4325
4326 scid = __le16_to_cpu(rsp->scid);
4327 dcid = __le16_to_cpu(rsp->dcid);
4328
4329 BT_DBG("dcid 0x%4.4x scid 0x%4.4x", dcid, scid);
4330
4331 mutex_lock(&conn->chan_lock);
4332
4333 chan = __l2cap_get_chan_by_scid(conn, scid);
4334 if (!chan) {
4335 mutex_unlock(&conn->chan_lock);
4336 return 0;
4337 }
4338
4339 l2cap_chan_lock(chan);
4340
4341 l2cap_chan_hold(chan);
4342 l2cap_chan_del(chan, 0);
4343
4344 l2cap_chan_unlock(chan);
4345
4346 chan->ops->close(chan);
4347 l2cap_chan_put(chan);
4348
4349 mutex_unlock(&conn->chan_lock);
4350
4351 return 0;
4352 }
4353
4354 static inline int l2cap_information_req(struct l2cap_conn *conn,
4355 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4356 u8 *data)
4357 {
4358 struct l2cap_info_req *req = (struct l2cap_info_req *) data;
4359 u16 type;
4360
4361 if (cmd_len != sizeof(*req))
4362 return -EPROTO;
4363
4364 type = __le16_to_cpu(req->type);
4365
4366 BT_DBG("type 0x%4.4x", type);
4367
4368 if (type == L2CAP_IT_FEAT_MASK) {
4369 u8 buf[8];
4370 u32 feat_mask = l2cap_feat_mask;
4371 struct l2cap_info_rsp *rsp = (struct l2cap_info_rsp *) buf;
4372 rsp->type = cpu_to_le16(L2CAP_IT_FEAT_MASK);
4373 rsp->result = cpu_to_le16(L2CAP_IR_SUCCESS);
4374 if (!disable_ertm)
4375 feat_mask |= L2CAP_FEAT_ERTM | L2CAP_FEAT_STREAMING
4376 | L2CAP_FEAT_FCS;
4377 if (conn->local_fixed_chan & L2CAP_FC_A2MP)
4378 feat_mask |= L2CAP_FEAT_EXT_FLOW
4379 | L2CAP_FEAT_EXT_WINDOW;
4380
4381 put_unaligned_le32(feat_mask, rsp->data);
4382 l2cap_send_cmd(conn, cmd->ident, L2CAP_INFO_RSP, sizeof(buf),
4383 buf);
4384 } else if (type == L2CAP_IT_FIXED_CHAN) {
4385 u8 buf[12];
4386 struct l2cap_info_rsp *rsp = (struct l2cap_info_rsp *) buf;
4387
4388 rsp->type = cpu_to_le16(L2CAP_IT_FIXED_CHAN);
4389 rsp->result = cpu_to_le16(L2CAP_IR_SUCCESS);
4390 rsp->data[0] = conn->local_fixed_chan;
4391 memset(rsp->data + 1, 0, 7);
4392 l2cap_send_cmd(conn, cmd->ident, L2CAP_INFO_RSP, sizeof(buf),
4393 buf);
4394 } else {
4395 struct l2cap_info_rsp rsp;
4396 rsp.type = cpu_to_le16(type);
4397 rsp.result = cpu_to_le16(L2CAP_IR_NOTSUPP);
4398 l2cap_send_cmd(conn, cmd->ident, L2CAP_INFO_RSP, sizeof(rsp),
4399 &rsp);
4400 }
4401
4402 return 0;
4403 }
4404
4405 static inline int l2cap_information_rsp(struct l2cap_conn *conn,
4406 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
4407 u8 *data)
4408 {
4409 struct l2cap_info_rsp *rsp = (struct l2cap_info_rsp *) data;
4410 u16 type, result;
4411
4412 if (cmd_len < sizeof(*rsp))
4413 return -EPROTO;
4414
4415 type = __le16_to_cpu(rsp->type);
4416 result = __le16_to_cpu(rsp->result);
4417
4418 BT_DBG("type 0x%4.4x result 0x%2.2x", type, result);
4419
4420 /* L2CAP Info req/rsp are unbound to channels, add extra checks */
4421 if (cmd->ident != conn->info_ident ||
4422 conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE)
4423 return 0;
4424
4425 cancel_delayed_work(&conn->info_timer);
4426
4427 if (result != L2CAP_IR_SUCCESS) {
4428 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
4429 conn->info_ident = 0;
4430
4431 l2cap_conn_start(conn);
4432
4433 return 0;
4434 }
4435
4436 switch (type) {
4437 case L2CAP_IT_FEAT_MASK:
4438 conn->feat_mask = get_unaligned_le32(rsp->data);
4439
4440 if (conn->feat_mask & L2CAP_FEAT_FIXED_CHAN) {
4441 struct l2cap_info_req req;
4442 req.type = cpu_to_le16(L2CAP_IT_FIXED_CHAN);
4443
4444 conn->info_ident = l2cap_get_ident(conn);
4445
4446 l2cap_send_cmd(conn, conn->info_ident,
4447 L2CAP_INFO_REQ, sizeof(req), &req);
4448 } else {
4449 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
4450 conn->info_ident = 0;
4451
4452 l2cap_conn_start(conn);
4453 }
4454 break;
4455
4456 case L2CAP_IT_FIXED_CHAN:
4457 conn->remote_fixed_chan = rsp->data[0];
4458 conn->info_state |= L2CAP_INFO_FEAT_MASK_REQ_DONE;
4459 conn->info_ident = 0;
4460
4461 l2cap_conn_start(conn);
4462 break;
4463 }
4464
4465 return 0;
4466 }
4467
4468 static int l2cap_create_channel_req(struct l2cap_conn *conn,
4469 struct l2cap_cmd_hdr *cmd,
4470 u16 cmd_len, void *data)
4471 {
4472 struct l2cap_create_chan_req *req = data;
4473 struct l2cap_create_chan_rsp rsp;
4474 struct l2cap_chan *chan;
4475 struct hci_dev *hdev;
4476 u16 psm, scid;
4477
4478 if (cmd_len != sizeof(*req))
4479 return -EPROTO;
4480
4481 if (!(conn->local_fixed_chan & L2CAP_FC_A2MP))
4482 return -EINVAL;
4483
4484 psm = le16_to_cpu(req->psm);
4485 scid = le16_to_cpu(req->scid);
4486
4487 BT_DBG("psm 0x%2.2x, scid 0x%4.4x, amp_id %d", psm, scid, req->amp_id);
4488
4489 /* For controller id 0 make BR/EDR connection */
4490 if (req->amp_id == AMP_ID_BREDR) {
4491 l2cap_connect(conn, cmd, data, L2CAP_CREATE_CHAN_RSP,
4492 req->amp_id);
4493 return 0;
4494 }
4495
4496 /* Validate AMP controller id */
4497 hdev = hci_dev_get(req->amp_id);
4498 if (!hdev)
4499 goto error;
4500
4501 if (hdev->dev_type != HCI_AMP || !test_bit(HCI_UP, &hdev->flags)) {
4502 hci_dev_put(hdev);
4503 goto error;
4504 }
4505
4506 chan = l2cap_connect(conn, cmd, data, L2CAP_CREATE_CHAN_RSP,
4507 req->amp_id);
4508 if (chan) {
4509 struct amp_mgr *mgr = conn->hcon->amp_mgr;
4510 struct hci_conn *hs_hcon;
4511
4512 hs_hcon = hci_conn_hash_lookup_ba(hdev, AMP_LINK,
4513 &conn->hcon->dst);
4514 if (!hs_hcon) {
4515 hci_dev_put(hdev);
4516 cmd_reject_invalid_cid(conn, cmd->ident, chan->scid,
4517 chan->dcid);
4518 return 0;
4519 }
4520
4521 BT_DBG("mgr %p bredr_chan %p hs_hcon %p", mgr, chan, hs_hcon);
4522
4523 mgr->bredr_chan = chan;
4524 chan->hs_hcon = hs_hcon;
4525 chan->fcs = L2CAP_FCS_NONE;
4526 conn->mtu = hdev->block_mtu;
4527 }
4528
4529 hci_dev_put(hdev);
4530
4531 return 0;
4532
4533 error:
4534 rsp.dcid = 0;
4535 rsp.scid = cpu_to_le16(scid);
4536 rsp.result = cpu_to_le16(L2CAP_CR_BAD_AMP);
4537 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
4538
4539 l2cap_send_cmd(conn, cmd->ident, L2CAP_CREATE_CHAN_RSP,
4540 sizeof(rsp), &rsp);
4541
4542 return 0;
4543 }
4544
4545 static void l2cap_send_move_chan_req(struct l2cap_chan *chan, u8 dest_amp_id)
4546 {
4547 struct l2cap_move_chan_req req;
4548 u8 ident;
4549
4550 BT_DBG("chan %p, dest_amp_id %d", chan, dest_amp_id);
4551
4552 ident = l2cap_get_ident(chan->conn);
4553 chan->ident = ident;
4554
4555 req.icid = cpu_to_le16(chan->scid);
4556 req.dest_amp_id = dest_amp_id;
4557
4558 l2cap_send_cmd(chan->conn, ident, L2CAP_MOVE_CHAN_REQ, sizeof(req),
4559 &req);
4560
4561 __set_chan_timer(chan, L2CAP_MOVE_TIMEOUT);
4562 }
4563
4564 static void l2cap_send_move_chan_rsp(struct l2cap_chan *chan, u16 result)
4565 {
4566 struct l2cap_move_chan_rsp rsp;
4567
4568 BT_DBG("chan %p, result 0x%4.4x", chan, result);
4569
4570 rsp.icid = cpu_to_le16(chan->dcid);
4571 rsp.result = cpu_to_le16(result);
4572
4573 l2cap_send_cmd(chan->conn, chan->ident, L2CAP_MOVE_CHAN_RSP,
4574 sizeof(rsp), &rsp);
4575 }
4576
4577 static void l2cap_send_move_chan_cfm(struct l2cap_chan *chan, u16 result)
4578 {
4579 struct l2cap_move_chan_cfm cfm;
4580
4581 BT_DBG("chan %p, result 0x%4.4x", chan, result);
4582
4583 chan->ident = l2cap_get_ident(chan->conn);
4584
4585 cfm.icid = cpu_to_le16(chan->scid);
4586 cfm.result = cpu_to_le16(result);
4587
4588 l2cap_send_cmd(chan->conn, chan->ident, L2CAP_MOVE_CHAN_CFM,
4589 sizeof(cfm), &cfm);
4590
4591 __set_chan_timer(chan, L2CAP_MOVE_TIMEOUT);
4592 }
4593
4594 static void l2cap_send_move_chan_cfm_icid(struct l2cap_conn *conn, u16 icid)
4595 {
4596 struct l2cap_move_chan_cfm cfm;
4597
4598 BT_DBG("conn %p, icid 0x%4.4x", conn, icid);
4599
4600 cfm.icid = cpu_to_le16(icid);
4601 cfm.result = cpu_to_le16(L2CAP_MC_UNCONFIRMED);
4602
4603 l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_MOVE_CHAN_CFM,
4604 sizeof(cfm), &cfm);
4605 }
4606
4607 static void l2cap_send_move_chan_cfm_rsp(struct l2cap_conn *conn, u8 ident,
4608 u16 icid)
4609 {
4610 struct l2cap_move_chan_cfm_rsp rsp;
4611
4612 BT_DBG("icid 0x%4.4x", icid);
4613
4614 rsp.icid = cpu_to_le16(icid);
4615 l2cap_send_cmd(conn, ident, L2CAP_MOVE_CHAN_CFM_RSP, sizeof(rsp), &rsp);
4616 }
4617
4618 static void __release_logical_link(struct l2cap_chan *chan)
4619 {
4620 chan->hs_hchan = NULL;
4621 chan->hs_hcon = NULL;
4622
4623 /* Placeholder - release the logical link */
4624 }
4625
4626 static void l2cap_logical_fail(struct l2cap_chan *chan)
4627 {
4628 /* Logical link setup failed */
4629 if (chan->state != BT_CONNECTED) {
4630 /* Create channel failure, disconnect */
4631 l2cap_send_disconn_req(chan, ECONNRESET);
4632 return;
4633 }
4634
4635 switch (chan->move_role) {
4636 case L2CAP_MOVE_ROLE_RESPONDER:
4637 l2cap_move_done(chan);
4638 l2cap_send_move_chan_rsp(chan, L2CAP_MR_NOT_SUPP);
4639 break;
4640 case L2CAP_MOVE_ROLE_INITIATOR:
4641 if (chan->move_state == L2CAP_MOVE_WAIT_LOGICAL_COMP ||
4642 chan->move_state == L2CAP_MOVE_WAIT_LOGICAL_CFM) {
4643 /* Remote has only sent pending or
4644 * success responses, clean up
4645 */
4646 l2cap_move_done(chan);
4647 }
4648
4649 /* Other amp move states imply that the move
4650 * has already aborted
4651 */
4652 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
4653 break;
4654 }
4655 }
4656
4657 static void l2cap_logical_finish_create(struct l2cap_chan *chan,
4658 struct hci_chan *hchan)
4659 {
4660 struct l2cap_conf_rsp rsp;
4661
4662 chan->hs_hchan = hchan;
4663 chan->hs_hcon->l2cap_data = chan->conn;
4664
4665 l2cap_send_efs_conf_rsp(chan, &rsp, chan->ident, 0);
4666
4667 if (test_bit(CONF_INPUT_DONE, &chan->conf_state)) {
4668 int err;
4669
4670 set_default_fcs(chan);
4671
4672 err = l2cap_ertm_init(chan);
4673 if (err < 0)
4674 l2cap_send_disconn_req(chan, -err);
4675 else
4676 l2cap_chan_ready(chan);
4677 }
4678 }
4679
4680 static void l2cap_logical_finish_move(struct l2cap_chan *chan,
4681 struct hci_chan *hchan)
4682 {
4683 chan->hs_hcon = hchan->conn;
4684 chan->hs_hcon->l2cap_data = chan->conn;
4685
4686 BT_DBG("move_state %d", chan->move_state);
4687
4688 switch (chan->move_state) {
4689 case L2CAP_MOVE_WAIT_LOGICAL_COMP:
4690 /* Move confirm will be sent after a success
4691 * response is received
4692 */
4693 chan->move_state = L2CAP_MOVE_WAIT_RSP_SUCCESS;
4694 break;
4695 case L2CAP_MOVE_WAIT_LOGICAL_CFM:
4696 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
4697 chan->move_state = L2CAP_MOVE_WAIT_LOCAL_BUSY;
4698 } else if (chan->move_role == L2CAP_MOVE_ROLE_INITIATOR) {
4699 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM_RSP;
4700 l2cap_send_move_chan_cfm(chan, L2CAP_MC_CONFIRMED);
4701 } else if (chan->move_role == L2CAP_MOVE_ROLE_RESPONDER) {
4702 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM;
4703 l2cap_send_move_chan_rsp(chan, L2CAP_MR_SUCCESS);
4704 }
4705 break;
4706 default:
4707 /* Move was not in expected state, free the channel */
4708 __release_logical_link(chan);
4709
4710 chan->move_state = L2CAP_MOVE_STABLE;
4711 }
4712 }
4713
4714 /* Call with chan locked */
4715 void l2cap_logical_cfm(struct l2cap_chan *chan, struct hci_chan *hchan,
4716 u8 status)
4717 {
4718 BT_DBG("chan %p, hchan %p, status %d", chan, hchan, status);
4719
4720 if (status) {
4721 l2cap_logical_fail(chan);
4722 __release_logical_link(chan);
4723 return;
4724 }
4725
4726 if (chan->state != BT_CONNECTED) {
4727 /* Ignore logical link if channel is on BR/EDR */
4728 if (chan->local_amp_id != AMP_ID_BREDR)
4729 l2cap_logical_finish_create(chan, hchan);
4730 } else {
4731 l2cap_logical_finish_move(chan, hchan);
4732 }
4733 }
4734
4735 void l2cap_move_start(struct l2cap_chan *chan)
4736 {
4737 BT_DBG("chan %p", chan);
4738
4739 if (chan->local_amp_id == AMP_ID_BREDR) {
4740 if (chan->chan_policy != BT_CHANNEL_POLICY_AMP_PREFERRED)
4741 return;
4742 chan->move_role = L2CAP_MOVE_ROLE_INITIATOR;
4743 chan->move_state = L2CAP_MOVE_WAIT_PREPARE;
4744 /* Placeholder - start physical link setup */
4745 } else {
4746 chan->move_role = L2CAP_MOVE_ROLE_INITIATOR;
4747 chan->move_state = L2CAP_MOVE_WAIT_RSP_SUCCESS;
4748 chan->move_id = 0;
4749 l2cap_move_setup(chan);
4750 l2cap_send_move_chan_req(chan, 0);
4751 }
4752 }
4753
4754 static void l2cap_do_create(struct l2cap_chan *chan, int result,
4755 u8 local_amp_id, u8 remote_amp_id)
4756 {
4757 BT_DBG("chan %p state %s %u -> %u", chan, state_to_string(chan->state),
4758 local_amp_id, remote_amp_id);
4759
4760 chan->fcs = L2CAP_FCS_NONE;
4761
4762 /* Outgoing channel on AMP */
4763 if (chan->state == BT_CONNECT) {
4764 if (result == L2CAP_CR_SUCCESS) {
4765 chan->local_amp_id = local_amp_id;
4766 l2cap_send_create_chan_req(chan, remote_amp_id);
4767 } else {
4768 /* Revert to BR/EDR connect */
4769 l2cap_send_conn_req(chan);
4770 }
4771
4772 return;
4773 }
4774
4775 /* Incoming channel on AMP */
4776 if (__l2cap_no_conn_pending(chan)) {
4777 struct l2cap_conn_rsp rsp;
4778 char buf[128];
4779 rsp.scid = cpu_to_le16(chan->dcid);
4780 rsp.dcid = cpu_to_le16(chan->scid);
4781
4782 if (result == L2CAP_CR_SUCCESS) {
4783 /* Send successful response */
4784 rsp.result = cpu_to_le16(L2CAP_CR_SUCCESS);
4785 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
4786 } else {
4787 /* Send negative response */
4788 rsp.result = cpu_to_le16(L2CAP_CR_NO_MEM);
4789 rsp.status = cpu_to_le16(L2CAP_CS_NO_INFO);
4790 }
4791
4792 l2cap_send_cmd(chan->conn, chan->ident, L2CAP_CREATE_CHAN_RSP,
4793 sizeof(rsp), &rsp);
4794
4795 if (result == L2CAP_CR_SUCCESS) {
4796 l2cap_state_change(chan, BT_CONFIG);
4797 set_bit(CONF_REQ_SENT, &chan->conf_state);
4798 l2cap_send_cmd(chan->conn, l2cap_get_ident(chan->conn),
4799 L2CAP_CONF_REQ,
4800 l2cap_build_conf_req(chan, buf, sizeof(buf)), buf);
4801 chan->num_conf_req++;
4802 }
4803 }
4804 }
4805
4806 static void l2cap_do_move_initiate(struct l2cap_chan *chan, u8 local_amp_id,
4807 u8 remote_amp_id)
4808 {
4809 l2cap_move_setup(chan);
4810 chan->move_id = local_amp_id;
4811 chan->move_state = L2CAP_MOVE_WAIT_RSP;
4812
4813 l2cap_send_move_chan_req(chan, remote_amp_id);
4814 }
4815
4816 static void l2cap_do_move_respond(struct l2cap_chan *chan, int result)
4817 {
4818 struct hci_chan *hchan = NULL;
4819
4820 /* Placeholder - get hci_chan for logical link */
4821
4822 if (hchan) {
4823 if (hchan->state == BT_CONNECTED) {
4824 /* Logical link is ready to go */
4825 chan->hs_hcon = hchan->conn;
4826 chan->hs_hcon->l2cap_data = chan->conn;
4827 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM;
4828 l2cap_send_move_chan_rsp(chan, L2CAP_MR_SUCCESS);
4829
4830 l2cap_logical_cfm(chan, hchan, L2CAP_MR_SUCCESS);
4831 } else {
4832 /* Wait for logical link to be ready */
4833 chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_CFM;
4834 }
4835 } else {
4836 /* Logical link not available */
4837 l2cap_send_move_chan_rsp(chan, L2CAP_MR_NOT_ALLOWED);
4838 }
4839 }
4840
4841 static void l2cap_do_move_cancel(struct l2cap_chan *chan, int result)
4842 {
4843 if (chan->move_role == L2CAP_MOVE_ROLE_RESPONDER) {
4844 u8 rsp_result;
4845 if (result == -EINVAL)
4846 rsp_result = L2CAP_MR_BAD_ID;
4847 else
4848 rsp_result = L2CAP_MR_NOT_ALLOWED;
4849
4850 l2cap_send_move_chan_rsp(chan, rsp_result);
4851 }
4852
4853 chan->move_role = L2CAP_MOVE_ROLE_NONE;
4854 chan->move_state = L2CAP_MOVE_STABLE;
4855
4856 /* Restart data transmission */
4857 l2cap_ertm_send(chan);
4858 }
4859
4860 /* Invoke with locked chan */
4861 void __l2cap_physical_cfm(struct l2cap_chan *chan, int result)
4862 {
4863 u8 local_amp_id = chan->local_amp_id;
4864 u8 remote_amp_id = chan->remote_amp_id;
4865
4866 BT_DBG("chan %p, result %d, local_amp_id %d, remote_amp_id %d",
4867 chan, result, local_amp_id, remote_amp_id);
4868
4869 if (chan->state == BT_DISCONN || chan->state == BT_CLOSED) {
4870 l2cap_chan_unlock(chan);
4871 return;
4872 }
4873
4874 if (chan->state != BT_CONNECTED) {
4875 l2cap_do_create(chan, result, local_amp_id, remote_amp_id);
4876 } else if (result != L2CAP_MR_SUCCESS) {
4877 l2cap_do_move_cancel(chan, result);
4878 } else {
4879 switch (chan->move_role) {
4880 case L2CAP_MOVE_ROLE_INITIATOR:
4881 l2cap_do_move_initiate(chan, local_amp_id,
4882 remote_amp_id);
4883 break;
4884 case L2CAP_MOVE_ROLE_RESPONDER:
4885 l2cap_do_move_respond(chan, result);
4886 break;
4887 default:
4888 l2cap_do_move_cancel(chan, result);
4889 break;
4890 }
4891 }
4892 }
4893
4894 static inline int l2cap_move_channel_req(struct l2cap_conn *conn,
4895 struct l2cap_cmd_hdr *cmd,
4896 u16 cmd_len, void *data)
4897 {
4898 struct l2cap_move_chan_req *req = data;
4899 struct l2cap_move_chan_rsp rsp;
4900 struct l2cap_chan *chan;
4901 u16 icid = 0;
4902 u16 result = L2CAP_MR_NOT_ALLOWED;
4903
4904 if (cmd_len != sizeof(*req))
4905 return -EPROTO;
4906
4907 icid = le16_to_cpu(req->icid);
4908
4909 BT_DBG("icid 0x%4.4x, dest_amp_id %d", icid, req->dest_amp_id);
4910
4911 if (!(conn->local_fixed_chan & L2CAP_FC_A2MP))
4912 return -EINVAL;
4913
4914 chan = l2cap_get_chan_by_dcid(conn, icid);
4915 if (!chan) {
4916 rsp.icid = cpu_to_le16(icid);
4917 rsp.result = cpu_to_le16(L2CAP_MR_NOT_ALLOWED);
4918 l2cap_send_cmd(conn, cmd->ident, L2CAP_MOVE_CHAN_RSP,
4919 sizeof(rsp), &rsp);
4920 return 0;
4921 }
4922
4923 chan->ident = cmd->ident;
4924
4925 if (chan->scid < L2CAP_CID_DYN_START ||
4926 chan->chan_policy == BT_CHANNEL_POLICY_BREDR_ONLY ||
4927 (chan->mode != L2CAP_MODE_ERTM &&
4928 chan->mode != L2CAP_MODE_STREAMING)) {
4929 result = L2CAP_MR_NOT_ALLOWED;
4930 goto send_move_response;
4931 }
4932
4933 if (chan->local_amp_id == req->dest_amp_id) {
4934 result = L2CAP_MR_SAME_ID;
4935 goto send_move_response;
4936 }
4937
4938 if (req->dest_amp_id != AMP_ID_BREDR) {
4939 struct hci_dev *hdev;
4940 hdev = hci_dev_get(req->dest_amp_id);
4941 if (!hdev || hdev->dev_type != HCI_AMP ||
4942 !test_bit(HCI_UP, &hdev->flags)) {
4943 if (hdev)
4944 hci_dev_put(hdev);
4945
4946 result = L2CAP_MR_BAD_ID;
4947 goto send_move_response;
4948 }
4949 hci_dev_put(hdev);
4950 }
4951
4952 /* Detect a move collision. Only send a collision response
4953 * if this side has "lost", otherwise proceed with the move.
4954 * The winner has the larger bd_addr.
4955 */
4956 if ((__chan_is_moving(chan) ||
4957 chan->move_role != L2CAP_MOVE_ROLE_NONE) &&
4958 bacmp(&conn->hcon->src, &conn->hcon->dst) > 0) {
4959 result = L2CAP_MR_COLLISION;
4960 goto send_move_response;
4961 }
4962
4963 chan->move_role = L2CAP_MOVE_ROLE_RESPONDER;
4964 l2cap_move_setup(chan);
4965 chan->move_id = req->dest_amp_id;
4966 icid = chan->dcid;
4967
4968 if (req->dest_amp_id == AMP_ID_BREDR) {
4969 /* Moving to BR/EDR */
4970 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
4971 chan->move_state = L2CAP_MOVE_WAIT_LOCAL_BUSY;
4972 result = L2CAP_MR_PEND;
4973 } else {
4974 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM;
4975 result = L2CAP_MR_SUCCESS;
4976 }
4977 } else {
4978 chan->move_state = L2CAP_MOVE_WAIT_PREPARE;
4979 /* Placeholder - uncomment when amp functions are available */
4980 /*amp_accept_physical(chan, req->dest_amp_id);*/
4981 result = L2CAP_MR_PEND;
4982 }
4983
4984 send_move_response:
4985 l2cap_send_move_chan_rsp(chan, result);
4986
4987 l2cap_chan_unlock(chan);
4988
4989 return 0;
4990 }
4991
4992 static void l2cap_move_continue(struct l2cap_conn *conn, u16 icid, u16 result)
4993 {
4994 struct l2cap_chan *chan;
4995 struct hci_chan *hchan = NULL;
4996
4997 chan = l2cap_get_chan_by_scid(conn, icid);
4998 if (!chan) {
4999 l2cap_send_move_chan_cfm_icid(conn, icid);
5000 return;
5001 }
5002
5003 __clear_chan_timer(chan);
5004 if (result == L2CAP_MR_PEND)
5005 __set_chan_timer(chan, L2CAP_MOVE_ERTX_TIMEOUT);
5006
5007 switch (chan->move_state) {
5008 case L2CAP_MOVE_WAIT_LOGICAL_COMP:
5009 /* Move confirm will be sent when logical link
5010 * is complete.
5011 */
5012 chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_CFM;
5013 break;
5014 case L2CAP_MOVE_WAIT_RSP_SUCCESS:
5015 if (result == L2CAP_MR_PEND) {
5016 break;
5017 } else if (test_bit(CONN_LOCAL_BUSY,
5018 &chan->conn_state)) {
5019 chan->move_state = L2CAP_MOVE_WAIT_LOCAL_BUSY;
5020 } else {
5021 /* Logical link is up or moving to BR/EDR,
5022 * proceed with move
5023 */
5024 chan->move_state = L2CAP_MOVE_WAIT_CONFIRM_RSP;
5025 l2cap_send_move_chan_cfm(chan, L2CAP_MC_CONFIRMED);
5026 }
5027 break;
5028 case L2CAP_MOVE_WAIT_RSP:
5029 /* Moving to AMP */
5030 if (result == L2CAP_MR_SUCCESS) {
5031 /* Remote is ready, send confirm immediately
5032 * after logical link is ready
5033 */
5034 chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_CFM;
5035 } else {
5036 /* Both logical link and move success
5037 * are required to confirm
5038 */
5039 chan->move_state = L2CAP_MOVE_WAIT_LOGICAL_COMP;
5040 }
5041
5042 /* Placeholder - get hci_chan for logical link */
5043 if (!hchan) {
5044 /* Logical link not available */
5045 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
5046 break;
5047 }
5048
5049 /* If the logical link is not yet connected, do not
5050 * send confirmation.
5051 */
5052 if (hchan->state != BT_CONNECTED)
5053 break;
5054
5055 /* Logical link is already ready to go */
5056
5057 chan->hs_hcon = hchan->conn;
5058 chan->hs_hcon->l2cap_data = chan->conn;
5059
5060 if (result == L2CAP_MR_SUCCESS) {
5061 /* Can confirm now */
5062 l2cap_send_move_chan_cfm(chan, L2CAP_MC_CONFIRMED);
5063 } else {
5064 /* Now only need move success
5065 * to confirm
5066 */
5067 chan->move_state = L2CAP_MOVE_WAIT_RSP_SUCCESS;
5068 }
5069
5070 l2cap_logical_cfm(chan, hchan, L2CAP_MR_SUCCESS);
5071 break;
5072 default:
5073 /* Any other amp move state means the move failed. */
5074 chan->move_id = chan->local_amp_id;
5075 l2cap_move_done(chan);
5076 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
5077 }
5078
5079 l2cap_chan_unlock(chan);
5080 }
5081
5082 static void l2cap_move_fail(struct l2cap_conn *conn, u8 ident, u16 icid,
5083 u16 result)
5084 {
5085 struct l2cap_chan *chan;
5086
5087 chan = l2cap_get_chan_by_ident(conn, ident);
5088 if (!chan) {
5089 /* Could not locate channel, icid is best guess */
5090 l2cap_send_move_chan_cfm_icid(conn, icid);
5091 return;
5092 }
5093
5094 __clear_chan_timer(chan);
5095
5096 if (chan->move_role == L2CAP_MOVE_ROLE_INITIATOR) {
5097 if (result == L2CAP_MR_COLLISION) {
5098 chan->move_role = L2CAP_MOVE_ROLE_RESPONDER;
5099 } else {
5100 /* Cleanup - cancel move */
5101 chan->move_id = chan->local_amp_id;
5102 l2cap_move_done(chan);
5103 }
5104 }
5105
5106 l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED);
5107
5108 l2cap_chan_unlock(chan);
5109 }
5110
5111 static int l2cap_move_channel_rsp(struct l2cap_conn *conn,
5112 struct l2cap_cmd_hdr *cmd,
5113 u16 cmd_len, void *data)
5114 {
5115 struct l2cap_move_chan_rsp *rsp = data;
5116 u16 icid, result;
5117
5118 if (cmd_len != sizeof(*rsp))
5119 return -EPROTO;
5120
5121 icid = le16_to_cpu(rsp->icid);
5122 result = le16_to_cpu(rsp->result);
5123
5124 BT_DBG("icid 0x%4.4x, result 0x%4.4x", icid, result);
5125
5126 if (result == L2CAP_MR_SUCCESS || result == L2CAP_MR_PEND)
5127 l2cap_move_continue(conn, icid, result);
5128 else
5129 l2cap_move_fail(conn, cmd->ident, icid, result);
5130
5131 return 0;
5132 }
5133
5134 static int l2cap_move_channel_confirm(struct l2cap_conn *conn,
5135 struct l2cap_cmd_hdr *cmd,
5136 u16 cmd_len, void *data)
5137 {
5138 struct l2cap_move_chan_cfm *cfm = data;
5139 struct l2cap_chan *chan;
5140 u16 icid, result;
5141
5142 if (cmd_len != sizeof(*cfm))
5143 return -EPROTO;
5144
5145 icid = le16_to_cpu(cfm->icid);
5146 result = le16_to_cpu(cfm->result);
5147
5148 BT_DBG("icid 0x%4.4x, result 0x%4.4x", icid, result);
5149
5150 chan = l2cap_get_chan_by_dcid(conn, icid);
5151 if (!chan) {
5152 /* Spec requires a response even if the icid was not found */
5153 l2cap_send_move_chan_cfm_rsp(conn, cmd->ident, icid);
5154 return 0;
5155 }
5156
5157 if (chan->move_state == L2CAP_MOVE_WAIT_CONFIRM) {
5158 if (result == L2CAP_MC_CONFIRMED) {
5159 chan->local_amp_id = chan->move_id;
5160 if (chan->local_amp_id == AMP_ID_BREDR)
5161 __release_logical_link(chan);
5162 } else {
5163 chan->move_id = chan->local_amp_id;
5164 }
5165
5166 l2cap_move_done(chan);
5167 }
5168
5169 l2cap_send_move_chan_cfm_rsp(conn, cmd->ident, icid);
5170
5171 l2cap_chan_unlock(chan);
5172
5173 return 0;
5174 }
5175
5176 static inline int l2cap_move_channel_confirm_rsp(struct l2cap_conn *conn,
5177 struct l2cap_cmd_hdr *cmd,
5178 u16 cmd_len, void *data)
5179 {
5180 struct l2cap_move_chan_cfm_rsp *rsp = data;
5181 struct l2cap_chan *chan;
5182 u16 icid;
5183
5184 if (cmd_len != sizeof(*rsp))
5185 return -EPROTO;
5186
5187 icid = le16_to_cpu(rsp->icid);
5188
5189 BT_DBG("icid 0x%4.4x", icid);
5190
5191 chan = l2cap_get_chan_by_scid(conn, icid);
5192 if (!chan)
5193 return 0;
5194
5195 __clear_chan_timer(chan);
5196
5197 if (chan->move_state == L2CAP_MOVE_WAIT_CONFIRM_RSP) {
5198 chan->local_amp_id = chan->move_id;
5199
5200 if (chan->local_amp_id == AMP_ID_BREDR && chan->hs_hchan)
5201 __release_logical_link(chan);
5202
5203 l2cap_move_done(chan);
5204 }
5205
5206 l2cap_chan_unlock(chan);
5207
5208 return 0;
5209 }
5210
5211 static inline int l2cap_conn_param_update_req(struct l2cap_conn *conn,
5212 struct l2cap_cmd_hdr *cmd,
5213 u16 cmd_len, u8 *data)
5214 {
5215 struct hci_conn *hcon = conn->hcon;
5216 struct l2cap_conn_param_update_req *req;
5217 struct l2cap_conn_param_update_rsp rsp;
5218 u16 min, max, latency, to_multiplier;
5219 int err;
5220
5221 if (hcon->role != HCI_ROLE_MASTER)
5222 return -EINVAL;
5223
5224 if (cmd_len != sizeof(struct l2cap_conn_param_update_req))
5225 return -EPROTO;
5226
5227 req = (struct l2cap_conn_param_update_req *) data;
5228 min = __le16_to_cpu(req->min);
5229 max = __le16_to_cpu(req->max);
5230 latency = __le16_to_cpu(req->latency);
5231 to_multiplier = __le16_to_cpu(req->to_multiplier);
5232
5233 BT_DBG("min 0x%4.4x max 0x%4.4x latency: 0x%4.4x Timeout: 0x%4.4x",
5234 min, max, latency, to_multiplier);
5235
5236 memset(&rsp, 0, sizeof(rsp));
5237
5238 err = hci_check_conn_params(min, max, latency, to_multiplier);
5239 if (err)
5240 rsp.result = cpu_to_le16(L2CAP_CONN_PARAM_REJECTED);
5241 else
5242 rsp.result = cpu_to_le16(L2CAP_CONN_PARAM_ACCEPTED);
5243
5244 l2cap_send_cmd(conn, cmd->ident, L2CAP_CONN_PARAM_UPDATE_RSP,
5245 sizeof(rsp), &rsp);
5246
5247 if (!err) {
5248 u8 store_hint;
5249
5250 store_hint = hci_le_conn_update(hcon, min, max, latency,
5251 to_multiplier);
5252 mgmt_new_conn_param(hcon->hdev, &hcon->dst, hcon->dst_type,
5253 store_hint, min, max, latency,
5254 to_multiplier);
5255
5256 }
5257
5258 return 0;
5259 }
5260
5261 static int l2cap_le_connect_rsp(struct l2cap_conn *conn,
5262 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5263 u8 *data)
5264 {
5265 struct l2cap_le_conn_rsp *rsp = (struct l2cap_le_conn_rsp *) data;
5266 struct hci_conn *hcon = conn->hcon;
5267 u16 dcid, mtu, mps, credits, result;
5268 struct l2cap_chan *chan;
5269 int err, sec_level;
5270
5271 if (cmd_len < sizeof(*rsp))
5272 return -EPROTO;
5273
5274 dcid = __le16_to_cpu(rsp->dcid);
5275 mtu = __le16_to_cpu(rsp->mtu);
5276 mps = __le16_to_cpu(rsp->mps);
5277 credits = __le16_to_cpu(rsp->credits);
5278 result = __le16_to_cpu(rsp->result);
5279
5280 if (result == L2CAP_CR_SUCCESS && (mtu < 23 || mps < 23 ||
5281 dcid < L2CAP_CID_DYN_START ||
5282 dcid > L2CAP_CID_LE_DYN_END))
5283 return -EPROTO;
5284
5285 BT_DBG("dcid 0x%4.4x mtu %u mps %u credits %u result 0x%2.2x",
5286 dcid, mtu, mps, credits, result);
5287
5288 mutex_lock(&conn->chan_lock);
5289
5290 chan = __l2cap_get_chan_by_ident(conn, cmd->ident);
5291 if (!chan) {
5292 err = -EBADSLT;
5293 goto unlock;
5294 }
5295
5296 err = 0;
5297
5298 l2cap_chan_lock(chan);
5299
5300 switch (result) {
5301 case L2CAP_CR_SUCCESS:
5302 if (__l2cap_get_chan_by_dcid(conn, dcid)) {
5303 err = -EBADSLT;
5304 break;
5305 }
5306
5307 chan->ident = 0;
5308 chan->dcid = dcid;
5309 chan->omtu = mtu;
5310 chan->remote_mps = mps;
5311 chan->tx_credits = credits;
5312 l2cap_chan_ready(chan);
5313 break;
5314
5315 case L2CAP_CR_AUTHENTICATION:
5316 case L2CAP_CR_ENCRYPTION:
5317 /* If we already have MITM protection we can't do
5318 * anything.
5319 */
5320 if (hcon->sec_level > BT_SECURITY_MEDIUM) {
5321 l2cap_chan_del(chan, ECONNREFUSED);
5322 break;
5323 }
5324
5325 sec_level = hcon->sec_level + 1;
5326 if (chan->sec_level < sec_level)
5327 chan->sec_level = sec_level;
5328
5329 /* We'll need to send a new Connect Request */
5330 clear_bit(FLAG_LE_CONN_REQ_SENT, &chan->flags);
5331
5332 smp_conn_security(hcon, chan->sec_level);
5333 break;
5334
5335 default:
5336 l2cap_chan_del(chan, ECONNREFUSED);
5337 break;
5338 }
5339
5340 l2cap_chan_unlock(chan);
5341
5342 unlock:
5343 mutex_unlock(&conn->chan_lock);
5344
5345 return err;
5346 }
5347
5348 static inline int l2cap_bredr_sig_cmd(struct l2cap_conn *conn,
5349 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5350 u8 *data)
5351 {
5352 int err = 0;
5353
5354 switch (cmd->code) {
5355 case L2CAP_COMMAND_REJ:
5356 l2cap_command_rej(conn, cmd, cmd_len, data);
5357 break;
5358
5359 case L2CAP_CONN_REQ:
5360 err = l2cap_connect_req(conn, cmd, cmd_len, data);
5361 break;
5362
5363 case L2CAP_CONN_RSP:
5364 case L2CAP_CREATE_CHAN_RSP:
5365 l2cap_connect_create_rsp(conn, cmd, cmd_len, data);
5366 break;
5367
5368 case L2CAP_CONF_REQ:
5369 err = l2cap_config_req(conn, cmd, cmd_len, data);
5370 break;
5371
5372 case L2CAP_CONF_RSP:
5373 l2cap_config_rsp(conn, cmd, cmd_len, data);
5374 break;
5375
5376 case L2CAP_DISCONN_REQ:
5377 err = l2cap_disconnect_req(conn, cmd, cmd_len, data);
5378 break;
5379
5380 case L2CAP_DISCONN_RSP:
5381 l2cap_disconnect_rsp(conn, cmd, cmd_len, data);
5382 break;
5383
5384 case L2CAP_ECHO_REQ:
5385 l2cap_send_cmd(conn, cmd->ident, L2CAP_ECHO_RSP, cmd_len, data);
5386 break;
5387
5388 case L2CAP_ECHO_RSP:
5389 break;
5390
5391 case L2CAP_INFO_REQ:
5392 err = l2cap_information_req(conn, cmd, cmd_len, data);
5393 break;
5394
5395 case L2CAP_INFO_RSP:
5396 l2cap_information_rsp(conn, cmd, cmd_len, data);
5397 break;
5398
5399 case L2CAP_CREATE_CHAN_REQ:
5400 err = l2cap_create_channel_req(conn, cmd, cmd_len, data);
5401 break;
5402
5403 case L2CAP_MOVE_CHAN_REQ:
5404 err = l2cap_move_channel_req(conn, cmd, cmd_len, data);
5405 break;
5406
5407 case L2CAP_MOVE_CHAN_RSP:
5408 l2cap_move_channel_rsp(conn, cmd, cmd_len, data);
5409 break;
5410
5411 case L2CAP_MOVE_CHAN_CFM:
5412 err = l2cap_move_channel_confirm(conn, cmd, cmd_len, data);
5413 break;
5414
5415 case L2CAP_MOVE_CHAN_CFM_RSP:
5416 l2cap_move_channel_confirm_rsp(conn, cmd, cmd_len, data);
5417 break;
5418
5419 default:
5420 BT_ERR("Unknown BR/EDR signaling command 0x%2.2x", cmd->code);
5421 err = -EINVAL;
5422 break;
5423 }
5424
5425 return err;
5426 }
5427
5428 static int l2cap_le_connect_req(struct l2cap_conn *conn,
5429 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5430 u8 *data)
5431 {
5432 struct l2cap_le_conn_req *req = (struct l2cap_le_conn_req *) data;
5433 struct l2cap_le_conn_rsp rsp;
5434 struct l2cap_chan *chan, *pchan;
5435 u16 dcid, scid, credits, mtu, mps;
5436 __le16 psm;
5437 u8 result;
5438
5439 if (cmd_len != sizeof(*req))
5440 return -EPROTO;
5441
5442 scid = __le16_to_cpu(req->scid);
5443 mtu = __le16_to_cpu(req->mtu);
5444 mps = __le16_to_cpu(req->mps);
5445 psm = req->psm;
5446 dcid = 0;
5447 credits = 0;
5448
5449 if (mtu < 23 || mps < 23)
5450 return -EPROTO;
5451
5452 BT_DBG("psm 0x%2.2x scid 0x%4.4x mtu %u mps %u", __le16_to_cpu(psm),
5453 scid, mtu, mps);
5454
5455 /* Check if we have socket listening on psm */
5456 pchan = l2cap_global_chan_by_psm(BT_LISTEN, psm, &conn->hcon->src,
5457 &conn->hcon->dst, LE_LINK);
5458 if (!pchan) {
5459 result = L2CAP_CR_BAD_PSM;
5460 chan = NULL;
5461 goto response;
5462 }
5463
5464 mutex_lock(&conn->chan_lock);
5465 l2cap_chan_lock(pchan);
5466
5467 if (!smp_sufficient_security(conn->hcon, pchan->sec_level,
5468 SMP_ALLOW_STK)) {
5469 result = L2CAP_CR_AUTHENTICATION;
5470 chan = NULL;
5471 goto response_unlock;
5472 }
5473
5474 /* Check for valid dynamic CID range */
5475 if (scid < L2CAP_CID_DYN_START || scid > L2CAP_CID_LE_DYN_END) {
5476 result = L2CAP_CR_INVALID_SCID;
5477 chan = NULL;
5478 goto response_unlock;
5479 }
5480
5481 /* Check if we already have channel with that dcid */
5482 if (__l2cap_get_chan_by_dcid(conn, scid)) {
5483 result = L2CAP_CR_SCID_IN_USE;
5484 chan = NULL;
5485 goto response_unlock;
5486 }
5487
5488 chan = pchan->ops->new_connection(pchan);
5489 if (!chan) {
5490 result = L2CAP_CR_NO_MEM;
5491 goto response_unlock;
5492 }
5493
5494 l2cap_le_flowctl_init(chan);
5495
5496 bacpy(&chan->src, &conn->hcon->src);
5497 bacpy(&chan->dst, &conn->hcon->dst);
5498 chan->src_type = bdaddr_src_type(conn->hcon);
5499 chan->dst_type = bdaddr_dst_type(conn->hcon);
5500 chan->psm = psm;
5501 chan->dcid = scid;
5502 chan->omtu = mtu;
5503 chan->remote_mps = mps;
5504 chan->tx_credits = __le16_to_cpu(req->credits);
5505
5506 __l2cap_chan_add(conn, chan);
5507 dcid = chan->scid;
5508 credits = chan->rx_credits;
5509
5510 __set_chan_timer(chan, chan->ops->get_sndtimeo(chan));
5511
5512 chan->ident = cmd->ident;
5513
5514 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) {
5515 l2cap_state_change(chan, BT_CONNECT2);
5516 /* The following result value is actually not defined
5517 * for LE CoC but we use it to let the function know
5518 * that it should bail out after doing its cleanup
5519 * instead of sending a response.
5520 */
5521 result = L2CAP_CR_PEND;
5522 chan->ops->defer(chan);
5523 } else {
5524 l2cap_chan_ready(chan);
5525 result = L2CAP_CR_SUCCESS;
5526 }
5527
5528 response_unlock:
5529 l2cap_chan_unlock(pchan);
5530 mutex_unlock(&conn->chan_lock);
5531 l2cap_chan_put(pchan);
5532
5533 if (result == L2CAP_CR_PEND)
5534 return 0;
5535
5536 response:
5537 if (chan) {
5538 rsp.mtu = cpu_to_le16(chan->imtu);
5539 rsp.mps = cpu_to_le16(chan->mps);
5540 } else {
5541 rsp.mtu = 0;
5542 rsp.mps = 0;
5543 }
5544
5545 rsp.dcid = cpu_to_le16(dcid);
5546 rsp.credits = cpu_to_le16(credits);
5547 rsp.result = cpu_to_le16(result);
5548
5549 l2cap_send_cmd(conn, cmd->ident, L2CAP_LE_CONN_RSP, sizeof(rsp), &rsp);
5550
5551 return 0;
5552 }
5553
5554 static inline int l2cap_le_credits(struct l2cap_conn *conn,
5555 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5556 u8 *data)
5557 {
5558 struct l2cap_le_credits *pkt;
5559 struct l2cap_chan *chan;
5560 u16 cid, credits, max_credits;
5561
5562 if (cmd_len != sizeof(*pkt))
5563 return -EPROTO;
5564
5565 pkt = (struct l2cap_le_credits *) data;
5566 cid = __le16_to_cpu(pkt->cid);
5567 credits = __le16_to_cpu(pkt->credits);
5568
5569 BT_DBG("cid 0x%4.4x credits 0x%4.4x", cid, credits);
5570
5571 chan = l2cap_get_chan_by_dcid(conn, cid);
5572 if (!chan)
5573 return -EBADSLT;
5574
5575 max_credits = LE_FLOWCTL_MAX_CREDITS - chan->tx_credits;
5576 if (credits > max_credits) {
5577 BT_ERR("LE credits overflow");
5578 l2cap_send_disconn_req(chan, ECONNRESET);
5579 l2cap_chan_unlock(chan);
5580
5581 /* Return 0 so that we don't trigger an unnecessary
5582 * command reject packet.
5583 */
5584 return 0;
5585 }
5586
5587 chan->tx_credits += credits;
5588
5589 /* Resume sending */
5590 l2cap_le_flowctl_send(chan);
5591
5592 if (chan->tx_credits)
5593 chan->ops->resume(chan);
5594
5595 l2cap_chan_unlock(chan);
5596
5597 return 0;
5598 }
5599
5600 static inline int l2cap_le_command_rej(struct l2cap_conn *conn,
5601 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5602 u8 *data)
5603 {
5604 struct l2cap_cmd_rej_unk *rej = (struct l2cap_cmd_rej_unk *) data;
5605 struct l2cap_chan *chan;
5606
5607 if (cmd_len < sizeof(*rej))
5608 return -EPROTO;
5609
5610 mutex_lock(&conn->chan_lock);
5611
5612 chan = __l2cap_get_chan_by_ident(conn, cmd->ident);
5613 if (!chan)
5614 goto done;
5615
5616 l2cap_chan_lock(chan);
5617 l2cap_chan_del(chan, ECONNREFUSED);
5618 l2cap_chan_unlock(chan);
5619
5620 done:
5621 mutex_unlock(&conn->chan_lock);
5622 return 0;
5623 }
5624
5625 static inline int l2cap_le_sig_cmd(struct l2cap_conn *conn,
5626 struct l2cap_cmd_hdr *cmd, u16 cmd_len,
5627 u8 *data)
5628 {
5629 int err = 0;
5630
5631 switch (cmd->code) {
5632 case L2CAP_COMMAND_REJ:
5633 l2cap_le_command_rej(conn, cmd, cmd_len, data);
5634 break;
5635
5636 case L2CAP_CONN_PARAM_UPDATE_REQ:
5637 err = l2cap_conn_param_update_req(conn, cmd, cmd_len, data);
5638 break;
5639
5640 case L2CAP_CONN_PARAM_UPDATE_RSP:
5641 break;
5642
5643 case L2CAP_LE_CONN_RSP:
5644 l2cap_le_connect_rsp(conn, cmd, cmd_len, data);
5645 break;
5646
5647 case L2CAP_LE_CONN_REQ:
5648 err = l2cap_le_connect_req(conn, cmd, cmd_len, data);
5649 break;
5650
5651 case L2CAP_LE_CREDITS:
5652 err = l2cap_le_credits(conn, cmd, cmd_len, data);
5653 break;
5654
5655 case L2CAP_DISCONN_REQ:
5656 err = l2cap_disconnect_req(conn, cmd, cmd_len, data);
5657 break;
5658
5659 case L2CAP_DISCONN_RSP:
5660 l2cap_disconnect_rsp(conn, cmd, cmd_len, data);
5661 break;
5662
5663 default:
5664 BT_ERR("Unknown LE signaling command 0x%2.2x", cmd->code);
5665 err = -EINVAL;
5666 break;
5667 }
5668
5669 return err;
5670 }
5671
5672 static inline void l2cap_le_sig_channel(struct l2cap_conn *conn,
5673 struct sk_buff *skb)
5674 {
5675 struct hci_conn *hcon = conn->hcon;
5676 struct l2cap_cmd_hdr *cmd;
5677 u16 len;
5678 int err;
5679
5680 if (hcon->type != LE_LINK)
5681 goto drop;
5682
5683 if (skb->len < L2CAP_CMD_HDR_SIZE)
5684 goto drop;
5685
5686 cmd = (void *) skb->data;
5687 skb_pull(skb, L2CAP_CMD_HDR_SIZE);
5688
5689 len = le16_to_cpu(cmd->len);
5690
5691 BT_DBG("code 0x%2.2x len %d id 0x%2.2x", cmd->code, len, cmd->ident);
5692
5693 if (len != skb->len || !cmd->ident) {
5694 BT_DBG("corrupted command");
5695 goto drop;
5696 }
5697
5698 err = l2cap_le_sig_cmd(conn, cmd, len, skb->data);
5699 if (err) {
5700 struct l2cap_cmd_rej_unk rej;
5701
5702 BT_ERR("Wrong link type (%d)", err);
5703
5704 rej.reason = cpu_to_le16(L2CAP_REJ_NOT_UNDERSTOOD);
5705 l2cap_send_cmd(conn, cmd->ident, L2CAP_COMMAND_REJ,
5706 sizeof(rej), &rej);
5707 }
5708
5709 drop:
5710 kfree_skb(skb);
5711 }
5712
5713 static inline void l2cap_sig_channel(struct l2cap_conn *conn,
5714 struct sk_buff *skb)
5715 {
5716 struct hci_conn *hcon = conn->hcon;
5717 u8 *data = skb->data;
5718 int len = skb->len;
5719 struct l2cap_cmd_hdr cmd;
5720 int err;
5721
5722 l2cap_raw_recv(conn, skb);
5723
5724 if (hcon->type != ACL_LINK)
5725 goto drop;
5726
5727 while (len >= L2CAP_CMD_HDR_SIZE) {
5728 u16 cmd_len;
5729 memcpy(&cmd, data, L2CAP_CMD_HDR_SIZE);
5730 data += L2CAP_CMD_HDR_SIZE;
5731 len -= L2CAP_CMD_HDR_SIZE;
5732
5733 cmd_len = le16_to_cpu(cmd.len);
5734
5735 BT_DBG("code 0x%2.2x len %d id 0x%2.2x", cmd.code, cmd_len,
5736 cmd.ident);
5737
5738 if (cmd_len > len || !cmd.ident) {
5739 BT_DBG("corrupted command");
5740 break;
5741 }
5742
5743 err = l2cap_bredr_sig_cmd(conn, &cmd, cmd_len, data);
5744 if (err) {
5745 struct l2cap_cmd_rej_unk rej;
5746
5747 BT_ERR("Wrong link type (%d)", err);
5748
5749 rej.reason = cpu_to_le16(L2CAP_REJ_NOT_UNDERSTOOD);
5750 l2cap_send_cmd(conn, cmd.ident, L2CAP_COMMAND_REJ,
5751 sizeof(rej), &rej);
5752 }
5753
5754 data += cmd_len;
5755 len -= cmd_len;
5756 }
5757
5758 drop:
5759 kfree_skb(skb);
5760 }
5761
5762 static int l2cap_check_fcs(struct l2cap_chan *chan, struct sk_buff *skb)
5763 {
5764 u16 our_fcs, rcv_fcs;
5765 int hdr_size;
5766
5767 if (test_bit(FLAG_EXT_CTRL, &chan->flags))
5768 hdr_size = L2CAP_EXT_HDR_SIZE;
5769 else
5770 hdr_size = L2CAP_ENH_HDR_SIZE;
5771
5772 if (chan->fcs == L2CAP_FCS_CRC16) {
5773 skb_trim(skb, skb->len - L2CAP_FCS_SIZE);
5774 rcv_fcs = get_unaligned_le16(skb->data + skb->len);
5775 our_fcs = crc16(0, skb->data - hdr_size, skb->len + hdr_size);
5776
5777 if (our_fcs != rcv_fcs)
5778 return -EBADMSG;
5779 }
5780 return 0;
5781 }
5782
5783 static void l2cap_send_i_or_rr_or_rnr(struct l2cap_chan *chan)
5784 {
5785 struct l2cap_ctrl control;
5786
5787 BT_DBG("chan %p", chan);
5788
5789 memset(&control, 0, sizeof(control));
5790 control.sframe = 1;
5791 control.final = 1;
5792 control.reqseq = chan->buffer_seq;
5793 set_bit(CONN_SEND_FBIT, &chan->conn_state);
5794
5795 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
5796 control.super = L2CAP_SUPER_RNR;
5797 l2cap_send_sframe(chan, &control);
5798 }
5799
5800 if (test_and_clear_bit(CONN_REMOTE_BUSY, &chan->conn_state) &&
5801 chan->unacked_frames > 0)
5802 __set_retrans_timer(chan);
5803
5804 /* Send pending iframes */
5805 l2cap_ertm_send(chan);
5806
5807 if (!test_bit(CONN_LOCAL_BUSY, &chan->conn_state) &&
5808 test_bit(CONN_SEND_FBIT, &chan->conn_state)) {
5809 /* F-bit wasn't sent in an s-frame or i-frame yet, so
5810 * send it now.
5811 */
5812 control.super = L2CAP_SUPER_RR;
5813 l2cap_send_sframe(chan, &control);
5814 }
5815 }
5816
5817 static void append_skb_frag(struct sk_buff *skb, struct sk_buff *new_frag,
5818 struct sk_buff **last_frag)
5819 {
5820 /* skb->len reflects data in skb as well as all fragments
5821 * skb->data_len reflects only data in fragments
5822 */
5823 if (!skb_has_frag_list(skb))
5824 skb_shinfo(skb)->frag_list = new_frag;
5825
5826 new_frag->next = NULL;
5827
5828 (*last_frag)->next = new_frag;
5829 *last_frag = new_frag;
5830
5831 skb->len += new_frag->len;
5832 skb->data_len += new_frag->len;
5833 skb->truesize += new_frag->truesize;
5834 }
5835
5836 static int l2cap_reassemble_sdu(struct l2cap_chan *chan, struct sk_buff *skb,
5837 struct l2cap_ctrl *control)
5838 {
5839 int err = -EINVAL;
5840
5841 switch (control->sar) {
5842 case L2CAP_SAR_UNSEGMENTED:
5843 if (chan->sdu)
5844 break;
5845
5846 err = chan->ops->recv(chan, skb);
5847 break;
5848
5849 case L2CAP_SAR_START:
5850 if (chan->sdu)
5851 break;
5852
5853 if (!pskb_may_pull(skb, L2CAP_SDULEN_SIZE))
5854 break;
5855
5856 chan->sdu_len = get_unaligned_le16(skb->data);
5857 skb_pull(skb, L2CAP_SDULEN_SIZE);
5858
5859 if (chan->sdu_len > chan->imtu) {
5860 err = -EMSGSIZE;
5861 break;
5862 }
5863
5864 if (skb->len >= chan->sdu_len)
5865 break;
5866
5867 chan->sdu = skb;
5868 chan->sdu_last_frag = skb;
5869
5870 skb = NULL;
5871 err = 0;
5872 break;
5873
5874 case L2CAP_SAR_CONTINUE:
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 = 0;
5886 break;
5887
5888 case L2CAP_SAR_END:
5889 if (!chan->sdu)
5890 break;
5891
5892 append_skb_frag(chan->sdu, skb,
5893 &chan->sdu_last_frag);
5894 skb = NULL;
5895
5896 if (chan->sdu->len != chan->sdu_len)
5897 break;
5898
5899 err = chan->ops->recv(chan, chan->sdu);
5900
5901 if (!err) {
5902 /* Reassembly complete */
5903 chan->sdu = NULL;
5904 chan->sdu_last_frag = NULL;
5905 chan->sdu_len = 0;
5906 }
5907 break;
5908 }
5909
5910 if (err) {
5911 kfree_skb(skb);
5912 kfree_skb(chan->sdu);
5913 chan->sdu = NULL;
5914 chan->sdu_last_frag = NULL;
5915 chan->sdu_len = 0;
5916 }
5917
5918 return err;
5919 }
5920
5921 static int l2cap_resegment(struct l2cap_chan *chan)
5922 {
5923 /* Placeholder */
5924 return 0;
5925 }
5926
5927 void l2cap_chan_busy(struct l2cap_chan *chan, int busy)
5928 {
5929 u8 event;
5930
5931 if (chan->mode != L2CAP_MODE_ERTM)
5932 return;
5933
5934 event = busy ? L2CAP_EV_LOCAL_BUSY_DETECTED : L2CAP_EV_LOCAL_BUSY_CLEAR;
5935 l2cap_tx(chan, NULL, NULL, event);
5936 }
5937
5938 static int l2cap_rx_queued_iframes(struct l2cap_chan *chan)
5939 {
5940 int err = 0;
5941 /* Pass sequential frames to l2cap_reassemble_sdu()
5942 * until a gap is encountered.
5943 */
5944
5945 BT_DBG("chan %p", chan);
5946
5947 while (!test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
5948 struct sk_buff *skb;
5949 BT_DBG("Searching for skb with txseq %d (queue len %d)",
5950 chan->buffer_seq, skb_queue_len(&chan->srej_q));
5951
5952 skb = l2cap_ertm_seq_in_queue(&chan->srej_q, chan->buffer_seq);
5953
5954 if (!skb)
5955 break;
5956
5957 skb_unlink(skb, &chan->srej_q);
5958 chan->buffer_seq = __next_seq(chan, chan->buffer_seq);
5959 err = l2cap_reassemble_sdu(chan, skb, &bt_cb(skb)->l2cap);
5960 if (err)
5961 break;
5962 }
5963
5964 if (skb_queue_empty(&chan->srej_q)) {
5965 chan->rx_state = L2CAP_RX_STATE_RECV;
5966 l2cap_send_ack(chan);
5967 }
5968
5969 return err;
5970 }
5971
5972 static void l2cap_handle_srej(struct l2cap_chan *chan,
5973 struct l2cap_ctrl *control)
5974 {
5975 struct sk_buff *skb;
5976
5977 BT_DBG("chan %p, control %p", chan, control);
5978
5979 if (control->reqseq == chan->next_tx_seq) {
5980 BT_DBG("Invalid reqseq %d, disconnecting", control->reqseq);
5981 l2cap_send_disconn_req(chan, ECONNRESET);
5982 return;
5983 }
5984
5985 skb = l2cap_ertm_seq_in_queue(&chan->tx_q, control->reqseq);
5986
5987 if (skb == NULL) {
5988 BT_DBG("Seq %d not available for retransmission",
5989 control->reqseq);
5990 return;
5991 }
5992
5993 if (chan->max_tx != 0 && bt_cb(skb)->l2cap.retries >= chan->max_tx) {
5994 BT_DBG("Retry limit exceeded (%d)", chan->max_tx);
5995 l2cap_send_disconn_req(chan, ECONNRESET);
5996 return;
5997 }
5998
5999 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6000
6001 if (control->poll) {
6002 l2cap_pass_to_tx(chan, control);
6003
6004 set_bit(CONN_SEND_FBIT, &chan->conn_state);
6005 l2cap_retransmit(chan, control);
6006 l2cap_ertm_send(chan);
6007
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 } else {
6013 l2cap_pass_to_tx_fbit(chan, control);
6014
6015 if (control->final) {
6016 if (chan->srej_save_reqseq != control->reqseq ||
6017 !test_and_clear_bit(CONN_SREJ_ACT,
6018 &chan->conn_state))
6019 l2cap_retransmit(chan, control);
6020 } else {
6021 l2cap_retransmit(chan, control);
6022 if (chan->tx_state == L2CAP_TX_STATE_WAIT_F) {
6023 set_bit(CONN_SREJ_ACT, &chan->conn_state);
6024 chan->srej_save_reqseq = control->reqseq;
6025 }
6026 }
6027 }
6028 }
6029
6030 static void l2cap_handle_rej(struct l2cap_chan *chan,
6031 struct l2cap_ctrl *control)
6032 {
6033 struct sk_buff *skb;
6034
6035 BT_DBG("chan %p, control %p", chan, control);
6036
6037 if (control->reqseq == chan->next_tx_seq) {
6038 BT_DBG("Invalid reqseq %d, disconnecting", control->reqseq);
6039 l2cap_send_disconn_req(chan, ECONNRESET);
6040 return;
6041 }
6042
6043 skb = l2cap_ertm_seq_in_queue(&chan->tx_q, control->reqseq);
6044
6045 if (chan->max_tx && skb &&
6046 bt_cb(skb)->l2cap.retries >= chan->max_tx) {
6047 BT_DBG("Retry limit exceeded (%d)", chan->max_tx);
6048 l2cap_send_disconn_req(chan, ECONNRESET);
6049 return;
6050 }
6051
6052 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6053
6054 l2cap_pass_to_tx(chan, control);
6055
6056 if (control->final) {
6057 if (!test_and_clear_bit(CONN_REJ_ACT, &chan->conn_state))
6058 l2cap_retransmit_all(chan, control);
6059 } else {
6060 l2cap_retransmit_all(chan, control);
6061 l2cap_ertm_send(chan);
6062 if (chan->tx_state == L2CAP_TX_STATE_WAIT_F)
6063 set_bit(CONN_REJ_ACT, &chan->conn_state);
6064 }
6065 }
6066
6067 static u8 l2cap_classify_txseq(struct l2cap_chan *chan, u16 txseq)
6068 {
6069 BT_DBG("chan %p, txseq %d", chan, txseq);
6070
6071 BT_DBG("last_acked_seq %d, expected_tx_seq %d", chan->last_acked_seq,
6072 chan->expected_tx_seq);
6073
6074 if (chan->rx_state == L2CAP_RX_STATE_SREJ_SENT) {
6075 if (__seq_offset(chan, txseq, chan->last_acked_seq) >=
6076 chan->tx_win) {
6077 /* See notes below regarding "double poll" and
6078 * invalid packets.
6079 */
6080 if (chan->tx_win <= ((chan->tx_win_max + 1) >> 1)) {
6081 BT_DBG("Invalid/Ignore - after SREJ");
6082 return L2CAP_TXSEQ_INVALID_IGNORE;
6083 } else {
6084 BT_DBG("Invalid - in window after SREJ sent");
6085 return L2CAP_TXSEQ_INVALID;
6086 }
6087 }
6088
6089 if (chan->srej_list.head == txseq) {
6090 BT_DBG("Expected SREJ");
6091 return L2CAP_TXSEQ_EXPECTED_SREJ;
6092 }
6093
6094 if (l2cap_ertm_seq_in_queue(&chan->srej_q, txseq)) {
6095 BT_DBG("Duplicate SREJ - txseq already stored");
6096 return L2CAP_TXSEQ_DUPLICATE_SREJ;
6097 }
6098
6099 if (l2cap_seq_list_contains(&chan->srej_list, txseq)) {
6100 BT_DBG("Unexpected SREJ - not requested");
6101 return L2CAP_TXSEQ_UNEXPECTED_SREJ;
6102 }
6103 }
6104
6105 if (chan->expected_tx_seq == txseq) {
6106 if (__seq_offset(chan, txseq, chan->last_acked_seq) >=
6107 chan->tx_win) {
6108 BT_DBG("Invalid - txseq outside tx window");
6109 return L2CAP_TXSEQ_INVALID;
6110 } else {
6111 BT_DBG("Expected");
6112 return L2CAP_TXSEQ_EXPECTED;
6113 }
6114 }
6115
6116 if (__seq_offset(chan, txseq, chan->last_acked_seq) <
6117 __seq_offset(chan, chan->expected_tx_seq, chan->last_acked_seq)) {
6118 BT_DBG("Duplicate - expected_tx_seq later than txseq");
6119 return L2CAP_TXSEQ_DUPLICATE;
6120 }
6121
6122 if (__seq_offset(chan, txseq, chan->last_acked_seq) >= chan->tx_win) {
6123 /* A source of invalid packets is a "double poll" condition,
6124 * where delays cause us to send multiple poll packets. If
6125 * the remote stack receives and processes both polls,
6126 * sequence numbers can wrap around in such a way that a
6127 * resent frame has a sequence number that looks like new data
6128 * with a sequence gap. This would trigger an erroneous SREJ
6129 * request.
6130 *
6131 * Fortunately, this is impossible with a tx window that's
6132 * less than half of the maximum sequence number, which allows
6133 * invalid frames to be safely ignored.
6134 *
6135 * With tx window sizes greater than half of the tx window
6136 * maximum, the frame is invalid and cannot be ignored. This
6137 * causes a disconnect.
6138 */
6139
6140 if (chan->tx_win <= ((chan->tx_win_max + 1) >> 1)) {
6141 BT_DBG("Invalid/Ignore - txseq outside tx window");
6142 return L2CAP_TXSEQ_INVALID_IGNORE;
6143 } else {
6144 BT_DBG("Invalid - txseq outside tx window");
6145 return L2CAP_TXSEQ_INVALID;
6146 }
6147 } else {
6148 BT_DBG("Unexpected - txseq indicates missing frames");
6149 return L2CAP_TXSEQ_UNEXPECTED;
6150 }
6151 }
6152
6153 static int l2cap_rx_state_recv(struct l2cap_chan *chan,
6154 struct l2cap_ctrl *control,
6155 struct sk_buff *skb, u8 event)
6156 {
6157 int err = 0;
6158 bool skb_in_use = false;
6159
6160 BT_DBG("chan %p, control %p, skb %p, event %d", chan, control, skb,
6161 event);
6162
6163 switch (event) {
6164 case L2CAP_EV_RECV_IFRAME:
6165 switch (l2cap_classify_txseq(chan, control->txseq)) {
6166 case L2CAP_TXSEQ_EXPECTED:
6167 l2cap_pass_to_tx(chan, control);
6168
6169 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
6170 BT_DBG("Busy, discarding expected seq %d",
6171 control->txseq);
6172 break;
6173 }
6174
6175 chan->expected_tx_seq = __next_seq(chan,
6176 control->txseq);
6177
6178 chan->buffer_seq = chan->expected_tx_seq;
6179 skb_in_use = true;
6180
6181 err = l2cap_reassemble_sdu(chan, skb, control);
6182 if (err)
6183 break;
6184
6185 if (control->final) {
6186 if (!test_and_clear_bit(CONN_REJ_ACT,
6187 &chan->conn_state)) {
6188 control->final = 0;
6189 l2cap_retransmit_all(chan, control);
6190 l2cap_ertm_send(chan);
6191 }
6192 }
6193
6194 if (!test_bit(CONN_LOCAL_BUSY, &chan->conn_state))
6195 l2cap_send_ack(chan);
6196 break;
6197 case L2CAP_TXSEQ_UNEXPECTED:
6198 l2cap_pass_to_tx(chan, control);
6199
6200 /* Can't issue SREJ frames in the local busy state.
6201 * Drop this frame, it will be seen as missing
6202 * when local busy is exited.
6203 */
6204 if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
6205 BT_DBG("Busy, discarding unexpected seq %d",
6206 control->txseq);
6207 break;
6208 }
6209
6210 /* There was a gap in the sequence, so an SREJ
6211 * must be sent for each missing frame. The
6212 * current frame is stored for later use.
6213 */
6214 skb_queue_tail(&chan->srej_q, skb);
6215 skb_in_use = true;
6216 BT_DBG("Queued %p (queue len %d)", skb,
6217 skb_queue_len(&chan->srej_q));
6218
6219 clear_bit(CONN_SREJ_ACT, &chan->conn_state);
6220 l2cap_seq_list_clear(&chan->srej_list);
6221 l2cap_send_srej(chan, control->txseq);
6222
6223 chan->rx_state = L2CAP_RX_STATE_SREJ_SENT;
6224 break;
6225 case L2CAP_TXSEQ_DUPLICATE:
6226 l2cap_pass_to_tx(chan, control);
6227 break;
6228 case L2CAP_TXSEQ_INVALID_IGNORE:
6229 break;
6230 case L2CAP_TXSEQ_INVALID:
6231 default:
6232 l2cap_send_disconn_req(chan, ECONNRESET);
6233 break;
6234 }
6235 break;
6236 case L2CAP_EV_RECV_RR:
6237 l2cap_pass_to_tx(chan, control);
6238 if (control->final) {
6239 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6240
6241 if (!test_and_clear_bit(CONN_REJ_ACT, &chan->conn_state) &&
6242 !__chan_is_moving(chan)) {
6243 control->final = 0;
6244 l2cap_retransmit_all(chan, control);
6245 }
6246
6247 l2cap_ertm_send(chan);
6248 } else if (control->poll) {
6249 l2cap_send_i_or_rr_or_rnr(chan);
6250 } else {
6251 if (test_and_clear_bit(CONN_REMOTE_BUSY,
6252 &chan->conn_state) &&
6253 chan->unacked_frames)
6254 __set_retrans_timer(chan);
6255
6256 l2cap_ertm_send(chan);
6257 }
6258 break;
6259 case L2CAP_EV_RECV_RNR:
6260 set_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6261 l2cap_pass_to_tx(chan, control);
6262 if (control && control->poll) {
6263 set_bit(CONN_SEND_FBIT, &chan->conn_state);
6264 l2cap_send_rr_or_rnr(chan, 0);
6265 }
6266 __clear_retrans_timer(chan);
6267 l2cap_seq_list_clear(&chan->retrans_list);
6268 break;
6269 case L2CAP_EV_RECV_REJ:
6270 l2cap_handle_rej(chan, control);
6271 break;
6272 case L2CAP_EV_RECV_SREJ:
6273 l2cap_handle_srej(chan, control);
6274 break;
6275 default:
6276 break;
6277 }
6278
6279 if (skb && !skb_in_use) {
6280 BT_DBG("Freeing %p", skb);
6281 kfree_skb(skb);
6282 }
6283
6284 return err;
6285 }
6286
6287 static int l2cap_rx_state_srej_sent(struct l2cap_chan *chan,
6288 struct l2cap_ctrl *control,
6289 struct sk_buff *skb, u8 event)
6290 {
6291 int err = 0;
6292 u16 txseq = control->txseq;
6293 bool skb_in_use = false;
6294
6295 BT_DBG("chan %p, control %p, skb %p, event %d", chan, control, skb,
6296 event);
6297
6298 switch (event) {
6299 case L2CAP_EV_RECV_IFRAME:
6300 switch (l2cap_classify_txseq(chan, txseq)) {
6301 case L2CAP_TXSEQ_EXPECTED:
6302 /* Keep frame for reassembly later */
6303 l2cap_pass_to_tx(chan, control);
6304 skb_queue_tail(&chan->srej_q, skb);
6305 skb_in_use = true;
6306 BT_DBG("Queued %p (queue len %d)", skb,
6307 skb_queue_len(&chan->srej_q));
6308
6309 chan->expected_tx_seq = __next_seq(chan, txseq);
6310 break;
6311 case L2CAP_TXSEQ_EXPECTED_SREJ:
6312 l2cap_seq_list_pop(&chan->srej_list);
6313
6314 l2cap_pass_to_tx(chan, control);
6315 skb_queue_tail(&chan->srej_q, skb);
6316 skb_in_use = true;
6317 BT_DBG("Queued %p (queue len %d)", skb,
6318 skb_queue_len(&chan->srej_q));
6319
6320 err = l2cap_rx_queued_iframes(chan);
6321 if (err)
6322 break;
6323
6324 break;
6325 case L2CAP_TXSEQ_UNEXPECTED:
6326 /* Got a frame that can't be reassembled yet.
6327 * Save it for later, and send SREJs to cover
6328 * the missing 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(chan, control->txseq);
6337 break;
6338 case L2CAP_TXSEQ_UNEXPECTED_SREJ:
6339 /* This frame was requested with an SREJ, but
6340 * some expected retransmitted frames are
6341 * missing. Request retransmission of missing
6342 * SREJ'd frames.
6343 */
6344 skb_queue_tail(&chan->srej_q, skb);
6345 skb_in_use = true;
6346 BT_DBG("Queued %p (queue len %d)", skb,
6347 skb_queue_len(&chan->srej_q));
6348
6349 l2cap_pass_to_tx(chan, control);
6350 l2cap_send_srej_list(chan, control->txseq);
6351 break;
6352 case L2CAP_TXSEQ_DUPLICATE_SREJ:
6353 /* We've already queued this frame. Drop this copy. */
6354 l2cap_pass_to_tx(chan, control);
6355 break;
6356 case L2CAP_TXSEQ_DUPLICATE:
6357 /* Expecting a later sequence number, so this frame
6358 * was already received. Ignore it completely.
6359 */
6360 break;
6361 case L2CAP_TXSEQ_INVALID_IGNORE:
6362 break;
6363 case L2CAP_TXSEQ_INVALID:
6364 default:
6365 l2cap_send_disconn_req(chan, ECONNRESET);
6366 break;
6367 }
6368 break;
6369 case L2CAP_EV_RECV_RR:
6370 l2cap_pass_to_tx(chan, control);
6371 if (control->final) {
6372 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6373
6374 if (!test_and_clear_bit(CONN_REJ_ACT,
6375 &chan->conn_state)) {
6376 control->final = 0;
6377 l2cap_retransmit_all(chan, control);
6378 }
6379
6380 l2cap_ertm_send(chan);
6381 } else if (control->poll) {
6382 if (test_and_clear_bit(CONN_REMOTE_BUSY,
6383 &chan->conn_state) &&
6384 chan->unacked_frames) {
6385 __set_retrans_timer(chan);
6386 }
6387
6388 set_bit(CONN_SEND_FBIT, &chan->conn_state);
6389 l2cap_send_srej_tail(chan);
6390 } else {
6391 if (test_and_clear_bit(CONN_REMOTE_BUSY,
6392 &chan->conn_state) &&
6393 chan->unacked_frames)
6394 __set_retrans_timer(chan);
6395
6396 l2cap_send_ack(chan);
6397 }
6398 break;
6399 case L2CAP_EV_RECV_RNR:
6400 set_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6401 l2cap_pass_to_tx(chan, control);
6402 if (control->poll) {
6403 l2cap_send_srej_tail(chan);
6404 } else {
6405 struct l2cap_ctrl rr_control;
6406 memset(&rr_control, 0, sizeof(rr_control));
6407 rr_control.sframe = 1;
6408 rr_control.super = L2CAP_SUPER_RR;
6409 rr_control.reqseq = chan->buffer_seq;
6410 l2cap_send_sframe(chan, &rr_control);
6411 }
6412
6413 break;
6414 case L2CAP_EV_RECV_REJ:
6415 l2cap_handle_rej(chan, control);
6416 break;
6417 case L2CAP_EV_RECV_SREJ:
6418 l2cap_handle_srej(chan, control);
6419 break;
6420 }
6421
6422 if (skb && !skb_in_use) {
6423 BT_DBG("Freeing %p", skb);
6424 kfree_skb(skb);
6425 }
6426
6427 return err;
6428 }
6429
6430 static int l2cap_finish_move(struct l2cap_chan *chan)
6431 {
6432 BT_DBG("chan %p", chan);
6433
6434 chan->rx_state = L2CAP_RX_STATE_RECV;
6435
6436 if (chan->hs_hcon)
6437 chan->conn->mtu = chan->hs_hcon->hdev->block_mtu;
6438 else
6439 chan->conn->mtu = chan->conn->hcon->hdev->acl_mtu;
6440
6441 return l2cap_resegment(chan);
6442 }
6443
6444 static int l2cap_rx_state_wait_p(struct l2cap_chan *chan,
6445 struct l2cap_ctrl *control,
6446 struct sk_buff *skb, u8 event)
6447 {
6448 int err;
6449
6450 BT_DBG("chan %p, control %p, skb %p, event %d", chan, control, skb,
6451 event);
6452
6453 if (!control->poll)
6454 return -EPROTO;
6455
6456 l2cap_process_reqseq(chan, control->reqseq);
6457
6458 if (!skb_queue_empty(&chan->tx_q))
6459 chan->tx_send_head = skb_peek(&chan->tx_q);
6460 else
6461 chan->tx_send_head = NULL;
6462
6463 /* Rewind next_tx_seq to the point expected
6464 * by the receiver.
6465 */
6466 chan->next_tx_seq = control->reqseq;
6467 chan->unacked_frames = 0;
6468
6469 err = l2cap_finish_move(chan);
6470 if (err)
6471 return err;
6472
6473 set_bit(CONN_SEND_FBIT, &chan->conn_state);
6474 l2cap_send_i_or_rr_or_rnr(chan);
6475
6476 if (event == L2CAP_EV_RECV_IFRAME)
6477 return -EPROTO;
6478
6479 return l2cap_rx_state_recv(chan, control, NULL, event);
6480 }
6481
6482 static int l2cap_rx_state_wait_f(struct l2cap_chan *chan,
6483 struct l2cap_ctrl *control,
6484 struct sk_buff *skb, u8 event)
6485 {
6486 int err;
6487
6488 if (!control->final)
6489 return -EPROTO;
6490
6491 clear_bit(CONN_REMOTE_BUSY, &chan->conn_state);
6492
6493 chan->rx_state = L2CAP_RX_STATE_RECV;
6494 l2cap_process_reqseq(chan, control->reqseq);
6495
6496 if (!skb_queue_empty(&chan->tx_q))
6497 chan->tx_send_head = skb_peek(&chan->tx_q);
6498 else
6499 chan->tx_send_head = NULL;
6500
6501 /* Rewind next_tx_seq to the point expected
6502 * by the receiver.
6503 */
6504 chan->next_tx_seq = control->reqseq;
6505 chan->unacked_frames = 0;
6506
6507 if (chan->hs_hcon)
6508 chan->conn->mtu = chan->hs_hcon->hdev->block_mtu;
6509 else
6510 chan->conn->mtu = chan->conn->hcon->hdev->acl_mtu;
6511
6512 err = l2cap_resegment(chan);
6513
6514 if (!err)
6515 err = l2cap_rx_state_recv(chan, control, skb, event);
6516
6517 return err;
6518 }
6519
6520 static bool __valid_reqseq(struct l2cap_chan *chan, u16 reqseq)
6521 {
6522 /* Make sure reqseq is for a packet that has been sent but not acked */
6523 u16 unacked;
6524
6525 unacked = __seq_offset(chan, chan->next_tx_seq, chan->expected_ack_seq);
6526 return __seq_offset(chan, chan->next_tx_seq, reqseq) <= unacked;
6527 }
6528
6529 static int l2cap_rx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
6530 struct sk_buff *skb, u8 event)
6531 {
6532 int err = 0;
6533
6534 BT_DBG("chan %p, control %p, skb %p, event %d, state %d", chan,
6535 control, skb, event, chan->rx_state);
6536
6537 if (__valid_reqseq(chan, control->reqseq)) {
6538 switch (chan->rx_state) {
6539 case L2CAP_RX_STATE_RECV:
6540 err = l2cap_rx_state_recv(chan, control, skb, event);
6541 break;
6542 case L2CAP_RX_STATE_SREJ_SENT:
6543 err = l2cap_rx_state_srej_sent(chan, control, skb,
6544 event);
6545 break;
6546 case L2CAP_RX_STATE_WAIT_P:
6547 err = l2cap_rx_state_wait_p(chan, control, skb, event);
6548 break;
6549 case L2CAP_RX_STATE_WAIT_F:
6550 err = l2cap_rx_state_wait_f(chan, control, skb, event);
6551 break;
6552 default:
6553 /* shut it down */
6554 break;
6555 }
6556 } else {
6557 BT_DBG("Invalid reqseq %d (next_tx_seq %d, expected_ack_seq %d",
6558 control->reqseq, chan->next_tx_seq,
6559 chan->expected_ack_seq);
6560 l2cap_send_disconn_req(chan, ECONNRESET);
6561 }
6562
6563 return err;
6564 }
6565
6566 static int l2cap_stream_rx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
6567 struct sk_buff *skb)
6568 {
6569 BT_DBG("chan %p, control %p, skb %p, state %d", chan, control, skb,
6570 chan->rx_state);
6571
6572 if (l2cap_classify_txseq(chan, control->txseq) ==
6573 L2CAP_TXSEQ_EXPECTED) {
6574 l2cap_pass_to_tx(chan, control);
6575
6576 BT_DBG("buffer_seq %d->%d", chan->buffer_seq,
6577 __next_seq(chan, chan->buffer_seq));
6578
6579 chan->buffer_seq = __next_seq(chan, chan->buffer_seq);
6580
6581 l2cap_reassemble_sdu(chan, skb, control);
6582 } else {
6583 if (chan->sdu) {
6584 kfree_skb(chan->sdu);
6585 chan->sdu = NULL;
6586 }
6587 chan->sdu_last_frag = NULL;
6588 chan->sdu_len = 0;
6589
6590 if (skb) {
6591 BT_DBG("Freeing %p", skb);
6592 kfree_skb(skb);
6593 }
6594 }
6595
6596 chan->last_acked_seq = control->txseq;
6597 chan->expected_tx_seq = __next_seq(chan, control->txseq);
6598
6599 return 0;
6600 }
6601
6602 static int l2cap_data_rcv(struct l2cap_chan *chan, struct sk_buff *skb)
6603 {
6604 struct l2cap_ctrl *control = &bt_cb(skb)->l2cap;
6605 u16 len;
6606 u8 event;
6607
6608 __unpack_control(chan, skb);
6609
6610 len = skb->len;
6611
6612 /*
6613 * We can just drop the corrupted I-frame here.
6614 * Receiver will miss it and start proper recovery
6615 * procedures and ask for retransmission.
6616 */
6617 if (l2cap_check_fcs(chan, skb))
6618 goto drop;
6619
6620 if (!control->sframe && control->sar == L2CAP_SAR_START)
6621 len -= L2CAP_SDULEN_SIZE;
6622
6623 if (chan->fcs == L2CAP_FCS_CRC16)
6624 len -= L2CAP_FCS_SIZE;
6625
6626 if (len > chan->mps) {
6627 l2cap_send_disconn_req(chan, ECONNRESET);
6628 goto drop;
6629 }
6630
6631 if ((chan->mode == L2CAP_MODE_ERTM ||
6632 chan->mode == L2CAP_MODE_STREAMING) && sk_filter(chan->data, skb))
6633 goto drop;
6634
6635 if (!control->sframe) {
6636 int err;
6637
6638 BT_DBG("iframe sar %d, reqseq %d, final %d, txseq %d",
6639 control->sar, control->reqseq, control->final,
6640 control->txseq);
6641
6642 /* Validate F-bit - F=0 always valid, F=1 only
6643 * valid in TX WAIT_F
6644 */
6645 if (control->final && chan->tx_state != L2CAP_TX_STATE_WAIT_F)
6646 goto drop;
6647
6648 if (chan->mode != L2CAP_MODE_STREAMING) {
6649 event = L2CAP_EV_RECV_IFRAME;
6650 err = l2cap_rx(chan, control, skb, event);
6651 } else {
6652 err = l2cap_stream_rx(chan, control, skb);
6653 }
6654
6655 if (err)
6656 l2cap_send_disconn_req(chan, ECONNRESET);
6657 } else {
6658 const u8 rx_func_to_event[4] = {
6659 L2CAP_EV_RECV_RR, L2CAP_EV_RECV_REJ,
6660 L2CAP_EV_RECV_RNR, L2CAP_EV_RECV_SREJ
6661 };
6662
6663 /* Only I-frames are expected in streaming mode */
6664 if (chan->mode == L2CAP_MODE_STREAMING)
6665 goto drop;
6666
6667 BT_DBG("sframe reqseq %d, final %d, poll %d, super %d",
6668 control->reqseq, control->final, control->poll,
6669 control->super);
6670
6671 if (len != 0) {
6672 BT_ERR("Trailing bytes: %d in sframe", len);
6673 l2cap_send_disconn_req(chan, ECONNRESET);
6674 goto drop;
6675 }
6676
6677 /* Validate F and P bits */
6678 if (control->final && (control->poll ||
6679 chan->tx_state != L2CAP_TX_STATE_WAIT_F))
6680 goto drop;
6681
6682 event = rx_func_to_event[control->super];
6683 if (l2cap_rx(chan, control, skb, event))
6684 l2cap_send_disconn_req(chan, ECONNRESET);
6685 }
6686
6687 return 0;
6688
6689 drop:
6690 kfree_skb(skb);
6691 return 0;
6692 }
6693
6694 static void l2cap_chan_le_send_credits(struct l2cap_chan *chan)
6695 {
6696 struct l2cap_conn *conn = chan->conn;
6697 struct l2cap_le_credits pkt;
6698 u16 return_credits;
6699
6700 /* We return more credits to the sender only after the amount of
6701 * credits falls below half of the initial amount.
6702 */
6703 if (chan->rx_credits >= (le_max_credits + 1) / 2)
6704 return;
6705
6706 return_credits = le_max_credits - chan->rx_credits;
6707
6708 BT_DBG("chan %p returning %u credits to sender", chan, return_credits);
6709
6710 chan->rx_credits += return_credits;
6711
6712 pkt.cid = cpu_to_le16(chan->scid);
6713 pkt.credits = cpu_to_le16(return_credits);
6714
6715 chan->ident = l2cap_get_ident(conn);
6716
6717 l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CREDITS, sizeof(pkt), &pkt);
6718 }
6719
6720 static int l2cap_le_data_rcv(struct l2cap_chan *chan, struct sk_buff *skb)
6721 {
6722 int err;
6723
6724 if (!chan->rx_credits) {
6725 BT_ERR("No credits to receive LE L2CAP data");
6726 l2cap_send_disconn_req(chan, ECONNRESET);
6727 return -ENOBUFS;
6728 }
6729
6730 if (chan->imtu < skb->len) {
6731 BT_ERR("Too big LE L2CAP PDU");
6732 return -ENOBUFS;
6733 }
6734
6735 chan->rx_credits--;
6736 BT_DBG("rx_credits %u -> %u", chan->rx_credits + 1, chan->rx_credits);
6737
6738 l2cap_chan_le_send_credits(chan);
6739
6740 err = 0;
6741
6742 if (!chan->sdu) {
6743 u16 sdu_len;
6744
6745 sdu_len = get_unaligned_le16(skb->data);
6746 skb_pull(skb, L2CAP_SDULEN_SIZE);
6747
6748 BT_DBG("Start of new SDU. sdu_len %u skb->len %u imtu %u",
6749 sdu_len, skb->len, chan->imtu);
6750
6751 if (sdu_len > chan->imtu) {
6752 BT_ERR("Too big LE L2CAP SDU length received");
6753 err = -EMSGSIZE;
6754 goto failed;
6755 }
6756
6757 if (skb->len > sdu_len) {
6758 BT_ERR("Too much LE L2CAP data received");
6759 err = -EINVAL;
6760 goto failed;
6761 }
6762
6763 if (skb->len == sdu_len)
6764 return chan->ops->recv(chan, skb);
6765
6766 chan->sdu = skb;
6767 chan->sdu_len = sdu_len;
6768 chan->sdu_last_frag = skb;
6769
6770 return 0;
6771 }
6772
6773 BT_DBG("SDU fragment. chan->sdu->len %u skb->len %u chan->sdu_len %u",
6774 chan->sdu->len, skb->len, chan->sdu_len);
6775
6776 if (chan->sdu->len + skb->len > chan->sdu_len) {
6777 BT_ERR("Too much LE L2CAP data received");
6778 err = -EINVAL;
6779 goto failed;
6780 }
6781
6782 append_skb_frag(chan->sdu, skb, &chan->sdu_last_frag);
6783 skb = NULL;
6784
6785 if (chan->sdu->len == chan->sdu_len) {
6786 err = chan->ops->recv(chan, chan->sdu);
6787 if (!err) {
6788 chan->sdu = NULL;
6789 chan->sdu_last_frag = NULL;
6790 chan->sdu_len = 0;
6791 }
6792 }
6793
6794 failed:
6795 if (err) {
6796 kfree_skb(skb);
6797 kfree_skb(chan->sdu);
6798 chan->sdu = NULL;
6799 chan->sdu_last_frag = NULL;
6800 chan->sdu_len = 0;
6801 }
6802
6803 /* We can't return an error here since we took care of the skb
6804 * freeing internally. An error return would cause the caller to
6805 * do a double-free of the skb.
6806 */
6807 return 0;
6808 }
6809
6810 static void l2cap_data_channel(struct l2cap_conn *conn, u16 cid,
6811 struct sk_buff *skb)
6812 {
6813 struct l2cap_chan *chan;
6814
6815 chan = l2cap_get_chan_by_scid(conn, cid);
6816 if (!chan) {
6817 if (cid == L2CAP_CID_A2MP) {
6818 chan = a2mp_channel_create(conn, skb);
6819 if (!chan) {
6820 kfree_skb(skb);
6821 return;
6822 }
6823
6824 l2cap_chan_lock(chan);
6825 } else {
6826 BT_DBG("unknown cid 0x%4.4x", cid);
6827 /* Drop packet and return */
6828 kfree_skb(skb);
6829 return;
6830 }
6831 }
6832
6833 BT_DBG("chan %p, len %d", chan, skb->len);
6834
6835 /* If we receive data on a fixed channel before the info req/rsp
6836 * procdure is done simply assume that the channel is supported
6837 * and mark it as ready.
6838 */
6839 if (chan->chan_type == L2CAP_CHAN_FIXED)
6840 l2cap_chan_ready(chan);
6841
6842 if (chan->state != BT_CONNECTED)
6843 goto drop;
6844
6845 switch (chan->mode) {
6846 case L2CAP_MODE_LE_FLOWCTL:
6847 if (l2cap_le_data_rcv(chan, skb) < 0)
6848 goto drop;
6849
6850 goto done;
6851
6852 case L2CAP_MODE_BASIC:
6853 /* If socket recv buffers overflows we drop data here
6854 * which is *bad* because L2CAP has to be reliable.
6855 * But we don't have any other choice. L2CAP doesn't
6856 * provide flow control mechanism. */
6857
6858 if (chan->imtu < skb->len) {
6859 BT_ERR("Dropping L2CAP data: receive buffer overflow");
6860 goto drop;
6861 }
6862
6863 if (!chan->ops->recv(chan, skb))
6864 goto done;
6865 break;
6866
6867 case L2CAP_MODE_ERTM:
6868 case L2CAP_MODE_STREAMING:
6869 l2cap_data_rcv(chan, skb);
6870 goto done;
6871
6872 default:
6873 BT_DBG("chan %p: bad mode 0x%2.2x", chan, chan->mode);
6874 break;
6875 }
6876
6877 drop:
6878 kfree_skb(skb);
6879
6880 done:
6881 l2cap_chan_unlock(chan);
6882 }
6883
6884 static void l2cap_conless_channel(struct l2cap_conn *conn, __le16 psm,
6885 struct sk_buff *skb)
6886 {
6887 struct hci_conn *hcon = conn->hcon;
6888 struct l2cap_chan *chan;
6889
6890 if (hcon->type != ACL_LINK)
6891 goto free_skb;
6892
6893 chan = l2cap_global_chan_by_psm(0, psm, &hcon->src, &hcon->dst,
6894 ACL_LINK);
6895 if (!chan)
6896 goto free_skb;
6897
6898 BT_DBG("chan %p, len %d", chan, skb->len);
6899
6900 if (chan->state != BT_BOUND && chan->state != BT_CONNECTED)
6901 goto drop;
6902
6903 if (chan->imtu < skb->len)
6904 goto drop;
6905
6906 /* Store remote BD_ADDR and PSM for msg_name */
6907 bacpy(&bt_cb(skb)->l2cap.bdaddr, &hcon->dst);
6908 bt_cb(skb)->l2cap.psm = psm;
6909
6910 if (!chan->ops->recv(chan, skb)) {
6911 l2cap_chan_put(chan);
6912 return;
6913 }
6914
6915 drop:
6916 l2cap_chan_put(chan);
6917 free_skb:
6918 kfree_skb(skb);
6919 }
6920
6921 static void l2cap_recv_frame(struct l2cap_conn *conn, struct sk_buff *skb)
6922 {
6923 struct l2cap_hdr *lh = (void *) skb->data;
6924 struct hci_conn *hcon = conn->hcon;
6925 u16 cid, len;
6926 __le16 psm;
6927
6928 if (hcon->state != BT_CONNECTED) {
6929 BT_DBG("queueing pending rx skb");
6930 skb_queue_tail(&conn->pending_rx, skb);
6931 return;
6932 }
6933
6934 skb_pull(skb, L2CAP_HDR_SIZE);
6935 cid = __le16_to_cpu(lh->cid);
6936 len = __le16_to_cpu(lh->len);
6937
6938 if (len != skb->len) {
6939 kfree_skb(skb);
6940 return;
6941 }
6942
6943 /* Since we can't actively block incoming LE connections we must
6944 * at least ensure that we ignore incoming data from them.
6945 */
6946 if (hcon->type == LE_LINK &&
6947 hci_bdaddr_list_lookup(&hcon->hdev->blacklist, &hcon->dst,
6948 bdaddr_dst_type(hcon))) {
6949 kfree_skb(skb);
6950 return;
6951 }
6952
6953 BT_DBG("len %d, cid 0x%4.4x", len, cid);
6954
6955 switch (cid) {
6956 case L2CAP_CID_SIGNALING:
6957 l2cap_sig_channel(conn, skb);
6958 break;
6959
6960 case L2CAP_CID_CONN_LESS:
6961 psm = get_unaligned((__le16 *) skb->data);
6962 skb_pull(skb, L2CAP_PSMLEN_SIZE);
6963 l2cap_conless_channel(conn, psm, skb);
6964 break;
6965
6966 case L2CAP_CID_LE_SIGNALING:
6967 l2cap_le_sig_channel(conn, skb);
6968 break;
6969
6970 default:
6971 l2cap_data_channel(conn, cid, skb);
6972 break;
6973 }
6974 }
6975
6976 static void process_pending_rx(struct work_struct *work)
6977 {
6978 struct l2cap_conn *conn = container_of(work, struct l2cap_conn,
6979 pending_rx_work);
6980 struct sk_buff *skb;
6981
6982 BT_DBG("");
6983
6984 while ((skb = skb_dequeue(&conn->pending_rx)))
6985 l2cap_recv_frame(conn, skb);
6986 }
6987
6988 static struct l2cap_conn *l2cap_conn_add(struct hci_conn *hcon)
6989 {
6990 struct l2cap_conn *conn = hcon->l2cap_data;
6991 struct hci_chan *hchan;
6992
6993 if (conn)
6994 return conn;
6995
6996 hchan = hci_chan_create(hcon);
6997 if (!hchan)
6998 return NULL;
6999
7000 conn = kzalloc(sizeof(*conn), GFP_KERNEL);
7001 if (!conn) {
7002 hci_chan_del(hchan);
7003 return NULL;
7004 }
7005
7006 kref_init(&conn->ref);
7007 hcon->l2cap_data = conn;
7008 conn->hcon = hci_conn_get(hcon);
7009 conn->hchan = hchan;
7010
7011 BT_DBG("hcon %p conn %p hchan %p", hcon, conn, hchan);
7012
7013 switch (hcon->type) {
7014 case LE_LINK:
7015 if (hcon->hdev->le_mtu) {
7016 conn->mtu = hcon->hdev->le_mtu;
7017 break;
7018 }
7019 /* fall through */
7020 default:
7021 conn->mtu = hcon->hdev->acl_mtu;
7022 break;
7023 }
7024
7025 conn->feat_mask = 0;
7026
7027 conn->local_fixed_chan = L2CAP_FC_SIG_BREDR | L2CAP_FC_CONNLESS;
7028
7029 if (hcon->type == ACL_LINK &&
7030 hci_dev_test_flag(hcon->hdev, HCI_HS_ENABLED))
7031 conn->local_fixed_chan |= L2CAP_FC_A2MP;
7032
7033 if (hci_dev_test_flag(hcon->hdev, HCI_LE_ENABLED) &&
7034 (bredr_sc_enabled(hcon->hdev) ||
7035 hci_dev_test_flag(hcon->hdev, HCI_FORCE_BREDR_SMP)))
7036 conn->local_fixed_chan |= L2CAP_FC_SMP_BREDR;
7037
7038 mutex_init(&conn->ident_lock);
7039 mutex_init(&conn->chan_lock);
7040
7041 INIT_LIST_HEAD(&conn->chan_l);
7042 INIT_LIST_HEAD(&conn->users);
7043
7044 INIT_DELAYED_WORK(&conn->info_timer, l2cap_info_timeout);
7045
7046 skb_queue_head_init(&conn->pending_rx);
7047 INIT_WORK(&conn->pending_rx_work, process_pending_rx);
7048 INIT_WORK(&conn->id_addr_update_work, l2cap_conn_update_id_addr);
7049
7050 conn->disc_reason = HCI_ERROR_REMOTE_USER_TERM;
7051
7052 return conn;
7053 }
7054
7055 static bool is_valid_psm(u16 psm, u8 dst_type) {
7056 if (!psm)
7057 return false;
7058
7059 if (bdaddr_type_is_le(dst_type))
7060 return (psm <= 0x00ff);
7061
7062 /* PSM must be odd and lsb of upper byte must be 0 */
7063 return ((psm & 0x0101) == 0x0001);
7064 }
7065
7066 int l2cap_chan_connect(struct l2cap_chan *chan, __le16 psm, u16 cid,
7067 bdaddr_t *dst, u8 dst_type)
7068 {
7069 struct l2cap_conn *conn;
7070 struct hci_conn *hcon;
7071 struct hci_dev *hdev;
7072 int err;
7073
7074 BT_DBG("%pMR -> %pMR (type %u) psm 0x%2.2x", &chan->src, dst,
7075 dst_type, __le16_to_cpu(psm));
7076
7077 hdev = hci_get_route(dst, &chan->src, chan->src_type);
7078 if (!hdev)
7079 return -EHOSTUNREACH;
7080
7081 hci_dev_lock(hdev);
7082
7083 if (!is_valid_psm(__le16_to_cpu(psm), dst_type) && !cid &&
7084 chan->chan_type != L2CAP_CHAN_RAW) {
7085 err = -EINVAL;
7086 goto done;
7087 }
7088
7089 if (chan->chan_type == L2CAP_CHAN_CONN_ORIENTED && !psm) {
7090 err = -EINVAL;
7091 goto done;
7092 }
7093
7094 if (chan->chan_type == L2CAP_CHAN_FIXED && !cid) {
7095 err = -EINVAL;
7096 goto done;
7097 }
7098
7099 switch (chan->mode) {
7100 case L2CAP_MODE_BASIC:
7101 break;
7102 case L2CAP_MODE_LE_FLOWCTL:
7103 l2cap_le_flowctl_init(chan);
7104 break;
7105 case L2CAP_MODE_ERTM:
7106 case L2CAP_MODE_STREAMING:
7107 if (!disable_ertm)
7108 break;
7109 /* fall through */
7110 default:
7111 err = -EOPNOTSUPP;
7112 goto done;
7113 }
7114
7115 switch (chan->state) {
7116 case BT_CONNECT:
7117 case BT_CONNECT2:
7118 case BT_CONFIG:
7119 /* Already connecting */
7120 err = 0;
7121 goto done;
7122
7123 case BT_CONNECTED:
7124 /* Already connected */
7125 err = -EISCONN;
7126 goto done;
7127
7128 case BT_OPEN:
7129 case BT_BOUND:
7130 /* Can connect */
7131 break;
7132
7133 default:
7134 err = -EBADFD;
7135 goto done;
7136 }
7137
7138 /* Set destination address and psm */
7139 bacpy(&chan->dst, dst);
7140 chan->dst_type = dst_type;
7141
7142 chan->psm = psm;
7143 chan->dcid = cid;
7144
7145 if (bdaddr_type_is_le(dst_type)) {
7146 /* Convert from L2CAP channel address type to HCI address type
7147 */
7148 if (dst_type == BDADDR_LE_PUBLIC)
7149 dst_type = ADDR_LE_DEV_PUBLIC;
7150 else
7151 dst_type = ADDR_LE_DEV_RANDOM;
7152
7153 if (hci_dev_test_flag(hdev, HCI_ADVERTISING))
7154 hcon = hci_connect_le(hdev, dst, dst_type,
7155 chan->sec_level,
7156 HCI_LE_CONN_TIMEOUT,
7157 HCI_ROLE_SLAVE);
7158 else
7159 hcon = hci_connect_le_scan(hdev, dst, dst_type,
7160 chan->sec_level,
7161 HCI_LE_CONN_TIMEOUT);
7162
7163 } else {
7164 u8 auth_type = l2cap_get_auth_type(chan);
7165 hcon = hci_connect_acl(hdev, dst, chan->sec_level, auth_type);
7166 }
7167
7168 if (IS_ERR(hcon)) {
7169 err = PTR_ERR(hcon);
7170 goto done;
7171 }
7172
7173 conn = l2cap_conn_add(hcon);
7174 if (!conn) {
7175 hci_conn_drop(hcon);
7176 err = -ENOMEM;
7177 goto done;
7178 }
7179
7180 mutex_lock(&conn->chan_lock);
7181 l2cap_chan_lock(chan);
7182
7183 if (cid && __l2cap_get_chan_by_dcid(conn, cid)) {
7184 hci_conn_drop(hcon);
7185 err = -EBUSY;
7186 goto chan_unlock;
7187 }
7188
7189 /* Update source addr of the socket */
7190 bacpy(&chan->src, &hcon->src);
7191 chan->src_type = bdaddr_src_type(hcon);
7192
7193 __l2cap_chan_add(conn, chan);
7194
7195 /* l2cap_chan_add takes its own ref so we can drop this one */
7196 hci_conn_drop(hcon);
7197
7198 l2cap_state_change(chan, BT_CONNECT);
7199 __set_chan_timer(chan, chan->ops->get_sndtimeo(chan));
7200
7201 /* Release chan->sport so that it can be reused by other
7202 * sockets (as it's only used for listening sockets).
7203 */
7204 write_lock(&chan_list_lock);
7205 chan->sport = 0;
7206 write_unlock(&chan_list_lock);
7207
7208 if (hcon->state == BT_CONNECTED) {
7209 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) {
7210 __clear_chan_timer(chan);
7211 if (l2cap_chan_check_security(chan, true))
7212 l2cap_state_change(chan, BT_CONNECTED);
7213 } else
7214 l2cap_do_start(chan);
7215 }
7216
7217 err = 0;
7218
7219 chan_unlock:
7220 l2cap_chan_unlock(chan);
7221 mutex_unlock(&conn->chan_lock);
7222 done:
7223 hci_dev_unlock(hdev);
7224 hci_dev_put(hdev);
7225 return err;
7226 }
7227 EXPORT_SYMBOL_GPL(l2cap_chan_connect);
7228
7229 /* ---- L2CAP interface with lower layer (HCI) ---- */
7230
7231 int l2cap_connect_ind(struct hci_dev *hdev, bdaddr_t *bdaddr)
7232 {
7233 int exact = 0, lm1 = 0, lm2 = 0;
7234 struct l2cap_chan *c;
7235
7236 BT_DBG("hdev %s, bdaddr %pMR", hdev->name, bdaddr);
7237
7238 /* Find listening sockets and check their link_mode */
7239 read_lock(&chan_list_lock);
7240 list_for_each_entry(c, &chan_list, global_l) {
7241 if (c->state != BT_LISTEN)
7242 continue;
7243
7244 if (!bacmp(&c->src, &hdev->bdaddr)) {
7245 lm1 |= HCI_LM_ACCEPT;
7246 if (test_bit(FLAG_ROLE_SWITCH, &c->flags))
7247 lm1 |= HCI_LM_MASTER;
7248 exact++;
7249 } else if (!bacmp(&c->src, BDADDR_ANY)) {
7250 lm2 |= HCI_LM_ACCEPT;
7251 if (test_bit(FLAG_ROLE_SWITCH, &c->flags))
7252 lm2 |= HCI_LM_MASTER;
7253 }
7254 }
7255 read_unlock(&chan_list_lock);
7256
7257 return exact ? lm1 : lm2;
7258 }
7259
7260 /* Find the next fixed channel in BT_LISTEN state, continue iteration
7261 * from an existing channel in the list or from the beginning of the
7262 * global list (by passing NULL as first parameter).
7263 */
7264 static struct l2cap_chan *l2cap_global_fixed_chan(struct l2cap_chan *c,
7265 struct hci_conn *hcon)
7266 {
7267 u8 src_type = bdaddr_src_type(hcon);
7268
7269 read_lock(&chan_list_lock);
7270
7271 if (c)
7272 c = list_next_entry(c, global_l);
7273 else
7274 c = list_entry(chan_list.next, typeof(*c), global_l);
7275
7276 list_for_each_entry_from(c, &chan_list, global_l) {
7277 if (c->chan_type != L2CAP_CHAN_FIXED)
7278 continue;
7279 if (c->state != BT_LISTEN)
7280 continue;
7281 if (bacmp(&c->src, &hcon->src) && bacmp(&c->src, BDADDR_ANY))
7282 continue;
7283 if (src_type != c->src_type)
7284 continue;
7285
7286 l2cap_chan_hold(c);
7287 read_unlock(&chan_list_lock);
7288 return c;
7289 }
7290
7291 read_unlock(&chan_list_lock);
7292
7293 return NULL;
7294 }
7295
7296 static void l2cap_connect_cfm(struct hci_conn *hcon, u8 status)
7297 {
7298 struct hci_dev *hdev = hcon->hdev;
7299 struct l2cap_conn *conn;
7300 struct l2cap_chan *pchan;
7301 u8 dst_type;
7302
7303 if (hcon->type != ACL_LINK && hcon->type != LE_LINK)
7304 return;
7305
7306 BT_DBG("hcon %p bdaddr %pMR status %d", hcon, &hcon->dst, status);
7307
7308 if (status) {
7309 l2cap_conn_del(hcon, bt_to_errno(status));
7310 return;
7311 }
7312
7313 conn = l2cap_conn_add(hcon);
7314 if (!conn)
7315 return;
7316
7317 dst_type = bdaddr_dst_type(hcon);
7318
7319 /* If device is blocked, do not create channels for it */
7320 if (hci_bdaddr_list_lookup(&hdev->blacklist, &hcon->dst, dst_type))
7321 return;
7322
7323 /* Find fixed channels and notify them of the new connection. We
7324 * use multiple individual lookups, continuing each time where
7325 * we left off, because the list lock would prevent calling the
7326 * potentially sleeping l2cap_chan_lock() function.
7327 */
7328 pchan = l2cap_global_fixed_chan(NULL, hcon);
7329 while (pchan) {
7330 struct l2cap_chan *chan, *next;
7331
7332 /* Client fixed channels should override server ones */
7333 if (__l2cap_get_chan_by_dcid(conn, pchan->scid))
7334 goto next;
7335
7336 l2cap_chan_lock(pchan);
7337 chan = pchan->ops->new_connection(pchan);
7338 if (chan) {
7339 bacpy(&chan->src, &hcon->src);
7340 bacpy(&chan->dst, &hcon->dst);
7341 chan->src_type = bdaddr_src_type(hcon);
7342 chan->dst_type = dst_type;
7343
7344 __l2cap_chan_add(conn, chan);
7345 }
7346
7347 l2cap_chan_unlock(pchan);
7348 next:
7349 next = l2cap_global_fixed_chan(pchan, hcon);
7350 l2cap_chan_put(pchan);
7351 pchan = next;
7352 }
7353
7354 l2cap_conn_ready(conn);
7355 }
7356
7357 int l2cap_disconn_ind(struct hci_conn *hcon)
7358 {
7359 struct l2cap_conn *conn = hcon->l2cap_data;
7360
7361 BT_DBG("hcon %p", hcon);
7362
7363 if (!conn)
7364 return HCI_ERROR_REMOTE_USER_TERM;
7365 return conn->disc_reason;
7366 }
7367
7368 static void l2cap_disconn_cfm(struct hci_conn *hcon, u8 reason)
7369 {
7370 if (hcon->type != ACL_LINK && hcon->type != LE_LINK)
7371 return;
7372
7373 BT_DBG("hcon %p reason %d", hcon, reason);
7374
7375 l2cap_conn_del(hcon, bt_to_errno(reason));
7376 }
7377
7378 static inline void l2cap_check_encryption(struct l2cap_chan *chan, u8 encrypt)
7379 {
7380 if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED)
7381 return;
7382
7383 if (encrypt == 0x00) {
7384 if (chan->sec_level == BT_SECURITY_MEDIUM) {
7385 __set_chan_timer(chan, L2CAP_ENC_TIMEOUT);
7386 } else if (chan->sec_level == BT_SECURITY_HIGH ||
7387 chan->sec_level == BT_SECURITY_FIPS)
7388 l2cap_chan_close(chan, ECONNREFUSED);
7389 } else {
7390 if (chan->sec_level == BT_SECURITY_MEDIUM)
7391 __clear_chan_timer(chan);
7392 }
7393 }
7394
7395 static void l2cap_security_cfm(struct hci_conn *hcon, u8 status, u8 encrypt)
7396 {
7397 struct l2cap_conn *conn = hcon->l2cap_data;
7398 struct l2cap_chan *chan;
7399
7400 if (!conn)
7401 return;
7402
7403 BT_DBG("conn %p status 0x%2.2x encrypt %u", conn, status, encrypt);
7404
7405 mutex_lock(&conn->chan_lock);
7406
7407 list_for_each_entry(chan, &conn->chan_l, list) {
7408 l2cap_chan_lock(chan);
7409
7410 BT_DBG("chan %p scid 0x%4.4x state %s", chan, chan->scid,
7411 state_to_string(chan->state));
7412
7413 if (chan->scid == L2CAP_CID_A2MP) {
7414 l2cap_chan_unlock(chan);
7415 continue;
7416 }
7417
7418 if (!status && encrypt)
7419 chan->sec_level = hcon->sec_level;
7420
7421 if (!__l2cap_no_conn_pending(chan)) {
7422 l2cap_chan_unlock(chan);
7423 continue;
7424 }
7425
7426 if (!status && (chan->state == BT_CONNECTED ||
7427 chan->state == BT_CONFIG)) {
7428 chan->ops->resume(chan);
7429 l2cap_check_encryption(chan, encrypt);
7430 l2cap_chan_unlock(chan);
7431 continue;
7432 }
7433
7434 if (chan->state == BT_CONNECT) {
7435 if (!status)
7436 l2cap_start_connection(chan);
7437 else
7438 __set_chan_timer(chan, L2CAP_DISC_TIMEOUT);
7439 } else if (chan->state == BT_CONNECT2 &&
7440 chan->mode != L2CAP_MODE_LE_FLOWCTL) {
7441 struct l2cap_conn_rsp rsp;
7442 __u16 res, stat;
7443
7444 if (!status) {
7445 if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) {
7446 res = L2CAP_CR_PEND;
7447 stat = L2CAP_CS_AUTHOR_PEND;
7448 chan->ops->defer(chan);
7449 } else {
7450 l2cap_state_change(chan, BT_CONFIG);
7451 res = L2CAP_CR_SUCCESS;
7452 stat = L2CAP_CS_NO_INFO;
7453 }
7454 } else {
7455 l2cap_state_change(chan, BT_DISCONN);
7456 __set_chan_timer(chan, L2CAP_DISC_TIMEOUT);
7457 res = L2CAP_CR_SEC_BLOCK;
7458 stat = L2CAP_CS_NO_INFO;
7459 }
7460
7461 rsp.scid = cpu_to_le16(chan->dcid);
7462 rsp.dcid = cpu_to_le16(chan->scid);
7463 rsp.result = cpu_to_le16(res);
7464 rsp.status = cpu_to_le16(stat);
7465 l2cap_send_cmd(conn, chan->ident, L2CAP_CONN_RSP,
7466 sizeof(rsp), &rsp);
7467
7468 if (!test_bit(CONF_REQ_SENT, &chan->conf_state) &&
7469 res == L2CAP_CR_SUCCESS) {
7470 char buf[128];
7471 set_bit(CONF_REQ_SENT, &chan->conf_state);
7472 l2cap_send_cmd(conn, l2cap_get_ident(conn),
7473 L2CAP_CONF_REQ,
7474 l2cap_build_conf_req(chan, buf, sizeof(buf)),
7475 buf);
7476 chan->num_conf_req++;
7477 }
7478 }
7479
7480 l2cap_chan_unlock(chan);
7481 }
7482
7483 mutex_unlock(&conn->chan_lock);
7484 }
7485
7486 void l2cap_recv_acldata(struct hci_conn *hcon, struct sk_buff *skb, u16 flags)
7487 {
7488 struct l2cap_conn *conn = hcon->l2cap_data;
7489 struct l2cap_hdr *hdr;
7490 int len;
7491
7492 /* For AMP controller do not create l2cap conn */
7493 if (!conn && hcon->hdev->dev_type != HCI_PRIMARY)
7494 goto drop;
7495
7496 if (!conn)
7497 conn = l2cap_conn_add(hcon);
7498
7499 if (!conn)
7500 goto drop;
7501
7502 BT_DBG("conn %p len %d flags 0x%x", conn, skb->len, flags);
7503
7504 switch (flags) {
7505 case ACL_START:
7506 case ACL_START_NO_FLUSH:
7507 case ACL_COMPLETE:
7508 if (conn->rx_len) {
7509 BT_ERR("Unexpected start frame (len %d)", skb->len);
7510 kfree_skb(conn->rx_skb);
7511 conn->rx_skb = NULL;
7512 conn->rx_len = 0;
7513 l2cap_conn_unreliable(conn, ECOMM);
7514 }
7515
7516 /* Start fragment always begin with Basic L2CAP header */
7517 if (skb->len < L2CAP_HDR_SIZE) {
7518 BT_ERR("Frame is too short (len %d)", skb->len);
7519 l2cap_conn_unreliable(conn, ECOMM);
7520 goto drop;
7521 }
7522
7523 hdr = (struct l2cap_hdr *) skb->data;
7524 len = __le16_to_cpu(hdr->len) + L2CAP_HDR_SIZE;
7525
7526 if (len == skb->len) {
7527 /* Complete frame received */
7528 l2cap_recv_frame(conn, skb);
7529 return;
7530 }
7531
7532 BT_DBG("Start: total len %d, frag len %d", len, skb->len);
7533
7534 if (skb->len > len) {
7535 BT_ERR("Frame is too long (len %d, expected len %d)",
7536 skb->len, len);
7537 l2cap_conn_unreliable(conn, ECOMM);
7538 goto drop;
7539 }
7540
7541 /* Allocate skb for the complete frame (with header) */
7542 conn->rx_skb = bt_skb_alloc(len, GFP_KERNEL);
7543 if (!conn->rx_skb)
7544 goto drop;
7545
7546 skb_copy_from_linear_data(skb, skb_put(conn->rx_skb, skb->len),
7547 skb->len);
7548 conn->rx_len = len - skb->len;
7549 break;
7550
7551 case ACL_CONT:
7552 BT_DBG("Cont: frag len %d (expecting %d)", skb->len, conn->rx_len);
7553
7554 if (!conn->rx_len) {
7555 BT_ERR("Unexpected continuation frame (len %d)", skb->len);
7556 l2cap_conn_unreliable(conn, ECOMM);
7557 goto drop;
7558 }
7559
7560 if (skb->len > conn->rx_len) {
7561 BT_ERR("Fragment is too long (len %d, expected %d)",
7562 skb->len, conn->rx_len);
7563 kfree_skb(conn->rx_skb);
7564 conn->rx_skb = NULL;
7565 conn->rx_len = 0;
7566 l2cap_conn_unreliable(conn, ECOMM);
7567 goto drop;
7568 }
7569
7570 skb_copy_from_linear_data(skb, skb_put(conn->rx_skb, skb->len),
7571 skb->len);
7572 conn->rx_len -= skb->len;
7573
7574 if (!conn->rx_len) {
7575 /* Complete frame received. l2cap_recv_frame
7576 * takes ownership of the skb so set the global
7577 * rx_skb pointer to NULL first.
7578 */
7579 struct sk_buff *rx_skb = conn->rx_skb;
7580 conn->rx_skb = NULL;
7581 l2cap_recv_frame(conn, rx_skb);
7582 }
7583 break;
7584 }
7585
7586 drop:
7587 kfree_skb(skb);
7588 }
7589
7590 static struct hci_cb l2cap_cb = {
7591 .name = "L2CAP",
7592 .connect_cfm = l2cap_connect_cfm,
7593 .disconn_cfm = l2cap_disconn_cfm,
7594 .security_cfm = l2cap_security_cfm,
7595 };
7596
7597 static int l2cap_debugfs_show(struct seq_file *f, void *p)
7598 {
7599 struct l2cap_chan *c;
7600
7601 read_lock(&chan_list_lock);
7602
7603 list_for_each_entry(c, &chan_list, global_l) {
7604 seq_printf(f, "%pMR (%u) %pMR (%u) %d %d 0x%4.4x 0x%4.4x %d %d %d %d\n",
7605 &c->src, c->src_type, &c->dst, c->dst_type,
7606 c->state, __le16_to_cpu(c->psm),
7607 c->scid, c->dcid, c->imtu, c->omtu,
7608 c->sec_level, c->mode);
7609 }
7610
7611 read_unlock(&chan_list_lock);
7612
7613 return 0;
7614 }
7615
7616 static int l2cap_debugfs_open(struct inode *inode, struct file *file)
7617 {
7618 return single_open(file, l2cap_debugfs_show, inode->i_private);
7619 }
7620
7621 static const struct file_operations l2cap_debugfs_fops = {
7622 .open = l2cap_debugfs_open,
7623 .read = seq_read,
7624 .llseek = seq_lseek,
7625 .release = single_release,
7626 };
7627
7628 static struct dentry *l2cap_debugfs;
7629
7630 int __init l2cap_init(void)
7631 {
7632 int err;
7633
7634 err = l2cap_init_sockets();
7635 if (err < 0)
7636 return err;
7637
7638 hci_register_cb(&l2cap_cb);
7639
7640 if (IS_ERR_OR_NULL(bt_debugfs))
7641 return 0;
7642
7643 l2cap_debugfs = debugfs_create_file("l2cap", 0444, bt_debugfs,
7644 NULL, &l2cap_debugfs_fops);
7645
7646 debugfs_create_u16("l2cap_le_max_credits", 0644, bt_debugfs,
7647 &le_max_credits);
7648 debugfs_create_u16("l2cap_le_default_mps", 0644, bt_debugfs,
7649 &le_default_mps);
7650
7651 return 0;
7652 }
7653
7654 void l2cap_exit(void)
7655 {
7656 debugfs_remove(l2cap_debugfs);
7657 hci_unregister_cb(&l2cap_cb);
7658 l2cap_cleanup_sockets();
7659 }
7660
7661 module_param(disable_ertm, bool, 0644);
7662 MODULE_PARM_DESC(disable_ertm, "Disable enhanced retransmission mode");
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